Chris Mason | 6cbd557 | 2007-06-12 09:07:21 -0400 | [diff] [blame] | 1 | /* |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 2 | * Copyright (C) 2007,2008 Oracle. All rights reserved. |
Chris Mason | 6cbd557 | 2007-06-12 09:07:21 -0400 | [diff] [blame] | 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public |
| 6 | * License v2 as published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 11 | * General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public |
| 14 | * License along with this program; if not, write to the |
| 15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 16 | * Boston, MA 021110-1307, USA. |
| 17 | */ |
| 18 | |
Chris Mason | a6b6e75 | 2007-10-15 16:22:39 -0400 | [diff] [blame] | 19 | #include <linux/sched.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 20 | #include <linux/slab.h> |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 21 | #include <linux/rbtree.h> |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 22 | #include "ctree.h" |
| 23 | #include "disk-io.h" |
Chris Mason | 7f5c151 | 2007-03-23 15:56:19 -0400 | [diff] [blame] | 24 | #include "transaction.h" |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 25 | #include "print-tree.h" |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 26 | #include "locking.h" |
Chris Mason | 9a8dd15 | 2007-02-23 08:38:36 -0500 | [diff] [blame] | 27 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame] | 28 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
| 29 | *root, struct btrfs_path *path, int level); |
| 30 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root |
Chris Mason | d4dbff9 | 2007-04-04 14:08:15 -0400 | [diff] [blame] | 31 | *root, struct btrfs_key *ins_key, |
Chris Mason | cc0c553 | 2007-10-25 15:42:57 -0400 | [diff] [blame] | 32 | struct btrfs_path *path, int data_size, int extend); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 33 | static int push_node_left(struct btrfs_trans_handle *trans, |
| 34 | struct btrfs_root *root, struct extent_buffer *dst, |
Chris Mason | 971a1f6 | 2008-04-24 10:54:32 -0400 | [diff] [blame] | 35 | struct extent_buffer *src, int empty); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 36 | static int balance_node_right(struct btrfs_trans_handle *trans, |
| 37 | struct btrfs_root *root, |
| 38 | struct extent_buffer *dst_buf, |
| 39 | struct extent_buffer *src_buf); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 40 | static void del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 41 | struct btrfs_path *path, int level, int slot, |
| 42 | int tree_mod_log); |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 43 | static void tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, |
| 44 | struct extent_buffer *eb); |
| 45 | struct extent_buffer *read_old_tree_block(struct btrfs_root *root, u64 bytenr, |
| 46 | u32 blocksize, u64 parent_transid, |
| 47 | u64 time_seq); |
| 48 | struct extent_buffer *btrfs_find_old_tree_block(struct btrfs_root *root, |
| 49 | u64 bytenr, u32 blocksize, |
| 50 | u64 time_seq); |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 51 | |
Chris Mason | 2c90e5d | 2007-04-02 10:50:19 -0400 | [diff] [blame] | 52 | struct btrfs_path *btrfs_alloc_path(void) |
| 53 | { |
Chris Mason | df24a2b | 2007-04-04 09:36:31 -0400 | [diff] [blame] | 54 | struct btrfs_path *path; |
Jeff Mahoney | e00f730 | 2009-02-12 14:11:25 -0500 | [diff] [blame] | 55 | path = kmem_cache_zalloc(btrfs_path_cachep, GFP_NOFS); |
Chris Mason | df24a2b | 2007-04-04 09:36:31 -0400 | [diff] [blame] | 56 | return path; |
Chris Mason | 2c90e5d | 2007-04-02 10:50:19 -0400 | [diff] [blame] | 57 | } |
| 58 | |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 59 | /* |
| 60 | * set all locked nodes in the path to blocking locks. This should |
| 61 | * be done before scheduling |
| 62 | */ |
| 63 | noinline void btrfs_set_path_blocking(struct btrfs_path *p) |
| 64 | { |
| 65 | int i; |
| 66 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 67 | if (!p->nodes[i] || !p->locks[i]) |
| 68 | continue; |
| 69 | btrfs_set_lock_blocking_rw(p->nodes[i], p->locks[i]); |
| 70 | if (p->locks[i] == BTRFS_READ_LOCK) |
| 71 | p->locks[i] = BTRFS_READ_LOCK_BLOCKING; |
| 72 | else if (p->locks[i] == BTRFS_WRITE_LOCK) |
| 73 | p->locks[i] = BTRFS_WRITE_LOCK_BLOCKING; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 74 | } |
| 75 | } |
| 76 | |
| 77 | /* |
| 78 | * reset all the locked nodes in the patch to spinning locks. |
Chris Mason | 4008c04 | 2009-02-12 14:09:45 -0500 | [diff] [blame] | 79 | * |
| 80 | * held is used to keep lockdep happy, when lockdep is enabled |
| 81 | * we set held to a blocking lock before we go around and |
| 82 | * retake all the spinlocks in the path. You can safely use NULL |
| 83 | * for held |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 84 | */ |
Chris Mason | 4008c04 | 2009-02-12 14:09:45 -0500 | [diff] [blame] | 85 | noinline void btrfs_clear_path_blocking(struct btrfs_path *p, |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 86 | struct extent_buffer *held, int held_rw) |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 87 | { |
| 88 | int i; |
Chris Mason | 4008c04 | 2009-02-12 14:09:45 -0500 | [diff] [blame] | 89 | |
| 90 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
| 91 | /* lockdep really cares that we take all of these spinlocks |
| 92 | * in the right order. If any of the locks in the path are not |
| 93 | * currently blocking, it is going to complain. So, make really |
| 94 | * really sure by forcing the path to blocking before we clear |
| 95 | * the path blocking. |
| 96 | */ |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 97 | if (held) { |
| 98 | btrfs_set_lock_blocking_rw(held, held_rw); |
| 99 | if (held_rw == BTRFS_WRITE_LOCK) |
| 100 | held_rw = BTRFS_WRITE_LOCK_BLOCKING; |
| 101 | else if (held_rw == BTRFS_READ_LOCK) |
| 102 | held_rw = BTRFS_READ_LOCK_BLOCKING; |
| 103 | } |
Chris Mason | 4008c04 | 2009-02-12 14:09:45 -0500 | [diff] [blame] | 104 | btrfs_set_path_blocking(p); |
| 105 | #endif |
| 106 | |
| 107 | for (i = BTRFS_MAX_LEVEL - 1; i >= 0; i--) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 108 | if (p->nodes[i] && p->locks[i]) { |
| 109 | btrfs_clear_lock_blocking_rw(p->nodes[i], p->locks[i]); |
| 110 | if (p->locks[i] == BTRFS_WRITE_LOCK_BLOCKING) |
| 111 | p->locks[i] = BTRFS_WRITE_LOCK; |
| 112 | else if (p->locks[i] == BTRFS_READ_LOCK_BLOCKING) |
| 113 | p->locks[i] = BTRFS_READ_LOCK; |
| 114 | } |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 115 | } |
Chris Mason | 4008c04 | 2009-02-12 14:09:45 -0500 | [diff] [blame] | 116 | |
| 117 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
| 118 | if (held) |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 119 | btrfs_clear_lock_blocking_rw(held, held_rw); |
Chris Mason | 4008c04 | 2009-02-12 14:09:45 -0500 | [diff] [blame] | 120 | #endif |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 121 | } |
| 122 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 123 | /* this also releases the path */ |
Chris Mason | 2c90e5d | 2007-04-02 10:50:19 -0400 | [diff] [blame] | 124 | void btrfs_free_path(struct btrfs_path *p) |
| 125 | { |
Jesper Juhl | ff175d5 | 2010-12-25 21:22:30 +0000 | [diff] [blame] | 126 | if (!p) |
| 127 | return; |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 128 | btrfs_release_path(p); |
Chris Mason | 2c90e5d | 2007-04-02 10:50:19 -0400 | [diff] [blame] | 129 | kmem_cache_free(btrfs_path_cachep, p); |
| 130 | } |
| 131 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 132 | /* |
| 133 | * path release drops references on the extent buffers in the path |
| 134 | * and it drops any locks held by this path |
| 135 | * |
| 136 | * It is safe to call this on paths that no locks or extent buffers held. |
| 137 | */ |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 138 | noinline void btrfs_release_path(struct btrfs_path *p) |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 139 | { |
| 140 | int i; |
Chris Mason | a213501 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 141 | |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 142 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 143 | p->slots[i] = 0; |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 144 | if (!p->nodes[i]) |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 145 | continue; |
| 146 | if (p->locks[i]) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 147 | btrfs_tree_unlock_rw(p->nodes[i], p->locks[i]); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 148 | p->locks[i] = 0; |
| 149 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 150 | free_extent_buffer(p->nodes[i]); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 151 | p->nodes[i] = NULL; |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 152 | } |
| 153 | } |
| 154 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 155 | /* |
| 156 | * safely gets a reference on the root node of a tree. A lock |
| 157 | * is not taken, so a concurrent writer may put a different node |
| 158 | * at the root of the tree. See btrfs_lock_root_node for the |
| 159 | * looping required. |
| 160 | * |
| 161 | * The extent buffer returned by this has a reference taken, so |
| 162 | * it won't disappear. It may stop being the root of the tree |
| 163 | * at any time because there are no locks held. |
| 164 | */ |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 165 | struct extent_buffer *btrfs_root_node(struct btrfs_root *root) |
| 166 | { |
| 167 | struct extent_buffer *eb; |
Chris Mason | 240f62c | 2011-03-23 14:54:42 -0400 | [diff] [blame] | 168 | |
Josef Bacik | 3083ee2 | 2012-03-09 16:01:49 -0500 | [diff] [blame] | 169 | while (1) { |
| 170 | rcu_read_lock(); |
| 171 | eb = rcu_dereference(root->node); |
| 172 | |
| 173 | /* |
| 174 | * RCU really hurts here, we could free up the root node because |
| 175 | * it was cow'ed but we may not get the new root node yet so do |
| 176 | * the inc_not_zero dance and if it doesn't work then |
| 177 | * synchronize_rcu and try again. |
| 178 | */ |
| 179 | if (atomic_inc_not_zero(&eb->refs)) { |
| 180 | rcu_read_unlock(); |
| 181 | break; |
| 182 | } |
| 183 | rcu_read_unlock(); |
| 184 | synchronize_rcu(); |
| 185 | } |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 186 | return eb; |
| 187 | } |
| 188 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 189 | /* loop around taking references on and locking the root node of the |
| 190 | * tree until you end up with a lock on the root. A locked buffer |
| 191 | * is returned, with a reference held. |
| 192 | */ |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 193 | struct extent_buffer *btrfs_lock_root_node(struct btrfs_root *root) |
| 194 | { |
| 195 | struct extent_buffer *eb; |
| 196 | |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 197 | while (1) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 198 | eb = btrfs_root_node(root); |
| 199 | btrfs_tree_lock(eb); |
Chris Mason | 240f62c | 2011-03-23 14:54:42 -0400 | [diff] [blame] | 200 | if (eb == root->node) |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 201 | break; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 202 | btrfs_tree_unlock(eb); |
| 203 | free_extent_buffer(eb); |
| 204 | } |
| 205 | return eb; |
| 206 | } |
| 207 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 208 | /* loop around taking references on and locking the root node of the |
| 209 | * tree until you end up with a lock on the root. A locked buffer |
| 210 | * is returned, with a reference held. |
| 211 | */ |
| 212 | struct extent_buffer *btrfs_read_lock_root_node(struct btrfs_root *root) |
| 213 | { |
| 214 | struct extent_buffer *eb; |
| 215 | |
| 216 | while (1) { |
| 217 | eb = btrfs_root_node(root); |
| 218 | btrfs_tree_read_lock(eb); |
| 219 | if (eb == root->node) |
| 220 | break; |
| 221 | btrfs_tree_read_unlock(eb); |
| 222 | free_extent_buffer(eb); |
| 223 | } |
| 224 | return eb; |
| 225 | } |
| 226 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 227 | /* cowonly root (everything not a reference counted cow subvolume), just get |
| 228 | * put onto a simple dirty list. transaction.c walks this to make sure they |
| 229 | * get properly updated on disk. |
| 230 | */ |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 231 | static void add_root_to_dirty_list(struct btrfs_root *root) |
| 232 | { |
Chris Mason | e5846fc | 2012-05-03 12:08:48 -0400 | [diff] [blame] | 233 | spin_lock(&root->fs_info->trans_lock); |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 234 | if (root->track_dirty && list_empty(&root->dirty_list)) { |
| 235 | list_add(&root->dirty_list, |
| 236 | &root->fs_info->dirty_cowonly_roots); |
| 237 | } |
Chris Mason | e5846fc | 2012-05-03 12:08:48 -0400 | [diff] [blame] | 238 | spin_unlock(&root->fs_info->trans_lock); |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 239 | } |
| 240 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 241 | /* |
| 242 | * used by snapshot creation to make a copy of a root for a tree with |
| 243 | * a given objectid. The buffer with the new root node is returned in |
| 244 | * cow_ret, and this func returns zero on success or a negative error code. |
| 245 | */ |
Chris Mason | be20aa9 | 2007-12-17 20:14:01 -0500 | [diff] [blame] | 246 | int btrfs_copy_root(struct btrfs_trans_handle *trans, |
| 247 | struct btrfs_root *root, |
| 248 | struct extent_buffer *buf, |
| 249 | struct extent_buffer **cow_ret, u64 new_root_objectid) |
| 250 | { |
| 251 | struct extent_buffer *cow; |
Chris Mason | be20aa9 | 2007-12-17 20:14:01 -0500 | [diff] [blame] | 252 | int ret = 0; |
| 253 | int level; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 254 | struct btrfs_disk_key disk_key; |
Chris Mason | be20aa9 | 2007-12-17 20:14:01 -0500 | [diff] [blame] | 255 | |
| 256 | WARN_ON(root->ref_cows && trans->transid != |
| 257 | root->fs_info->running_transaction->transid); |
| 258 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); |
| 259 | |
| 260 | level = btrfs_header_level(buf); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 261 | if (level == 0) |
| 262 | btrfs_item_key(buf, &disk_key, 0); |
| 263 | else |
| 264 | btrfs_node_key(buf, &disk_key, 0); |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 265 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 266 | cow = btrfs_alloc_free_block(trans, root, buf->len, 0, |
| 267 | new_root_objectid, &disk_key, level, |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 268 | buf->start, 0); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 269 | if (IS_ERR(cow)) |
Chris Mason | be20aa9 | 2007-12-17 20:14:01 -0500 | [diff] [blame] | 270 | return PTR_ERR(cow); |
| 271 | |
| 272 | copy_extent_buffer(cow, buf, 0, 0, cow->len); |
| 273 | btrfs_set_header_bytenr(cow, cow->start); |
| 274 | btrfs_set_header_generation(cow, trans->transid); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 275 | btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV); |
| 276 | btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN | |
| 277 | BTRFS_HEADER_FLAG_RELOC); |
| 278 | if (new_root_objectid == BTRFS_TREE_RELOC_OBJECTID) |
| 279 | btrfs_set_header_flag(cow, BTRFS_HEADER_FLAG_RELOC); |
| 280 | else |
| 281 | btrfs_set_header_owner(cow, new_root_objectid); |
Chris Mason | be20aa9 | 2007-12-17 20:14:01 -0500 | [diff] [blame] | 282 | |
Yan Zheng | 2b82032 | 2008-11-17 21:11:30 -0500 | [diff] [blame] | 283 | write_extent_buffer(cow, root->fs_info->fsid, |
| 284 | (unsigned long)btrfs_header_fsid(cow), |
| 285 | BTRFS_FSID_SIZE); |
| 286 | |
Chris Mason | be20aa9 | 2007-12-17 20:14:01 -0500 | [diff] [blame] | 287 | WARN_ON(btrfs_header_generation(buf) > trans->transid); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 288 | if (new_root_objectid == BTRFS_TREE_RELOC_OBJECTID) |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 289 | ret = btrfs_inc_ref(trans, root, cow, 1, 1); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 290 | else |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 291 | ret = btrfs_inc_ref(trans, root, cow, 0, 1); |
Chris Mason | 4aec2b5 | 2007-12-18 16:25:45 -0500 | [diff] [blame] | 292 | |
Chris Mason | be20aa9 | 2007-12-17 20:14:01 -0500 | [diff] [blame] | 293 | if (ret) |
| 294 | return ret; |
| 295 | |
| 296 | btrfs_mark_buffer_dirty(cow); |
| 297 | *cow_ret = cow; |
| 298 | return 0; |
| 299 | } |
| 300 | |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 301 | enum mod_log_op { |
| 302 | MOD_LOG_KEY_REPLACE, |
| 303 | MOD_LOG_KEY_ADD, |
| 304 | MOD_LOG_KEY_REMOVE, |
| 305 | MOD_LOG_KEY_REMOVE_WHILE_FREEING, |
| 306 | MOD_LOG_KEY_REMOVE_WHILE_MOVING, |
| 307 | MOD_LOG_MOVE_KEYS, |
| 308 | MOD_LOG_ROOT_REPLACE, |
| 309 | }; |
| 310 | |
| 311 | struct tree_mod_move { |
| 312 | int dst_slot; |
| 313 | int nr_items; |
| 314 | }; |
| 315 | |
| 316 | struct tree_mod_root { |
| 317 | u64 logical; |
| 318 | u8 level; |
| 319 | }; |
| 320 | |
| 321 | struct tree_mod_elem { |
| 322 | struct rb_node node; |
| 323 | u64 index; /* shifted logical */ |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 324 | u64 seq; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 325 | enum mod_log_op op; |
| 326 | |
| 327 | /* this is used for MOD_LOG_KEY_* and MOD_LOG_MOVE_KEYS operations */ |
| 328 | int slot; |
| 329 | |
| 330 | /* this is used for MOD_LOG_KEY* and MOD_LOG_ROOT_REPLACE */ |
| 331 | u64 generation; |
| 332 | |
| 333 | /* those are used for op == MOD_LOG_KEY_{REPLACE,REMOVE} */ |
| 334 | struct btrfs_disk_key key; |
| 335 | u64 blockptr; |
| 336 | |
| 337 | /* this is used for op == MOD_LOG_MOVE_KEYS */ |
| 338 | struct tree_mod_move move; |
| 339 | |
| 340 | /* this is used for op == MOD_LOG_ROOT_REPLACE */ |
| 341 | struct tree_mod_root old_root; |
| 342 | }; |
| 343 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 344 | static inline void tree_mod_log_read_lock(struct btrfs_fs_info *fs_info) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 345 | { |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 346 | read_lock(&fs_info->tree_mod_log_lock); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 347 | } |
| 348 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 349 | static inline void tree_mod_log_read_unlock(struct btrfs_fs_info *fs_info) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 350 | { |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 351 | read_unlock(&fs_info->tree_mod_log_lock); |
| 352 | } |
| 353 | |
| 354 | static inline void tree_mod_log_write_lock(struct btrfs_fs_info *fs_info) |
| 355 | { |
| 356 | write_lock(&fs_info->tree_mod_log_lock); |
| 357 | } |
| 358 | |
| 359 | static inline void tree_mod_log_write_unlock(struct btrfs_fs_info *fs_info) |
| 360 | { |
| 361 | write_unlock(&fs_info->tree_mod_log_lock); |
| 362 | } |
| 363 | |
| 364 | /* |
| 365 | * This adds a new blocker to the tree mod log's blocker list if the @elem |
| 366 | * passed does not already have a sequence number set. So when a caller expects |
| 367 | * to record tree modifications, it should ensure to set elem->seq to zero |
| 368 | * before calling btrfs_get_tree_mod_seq. |
| 369 | * Returns a fresh, unused tree log modification sequence number, even if no new |
| 370 | * blocker was added. |
| 371 | */ |
| 372 | u64 btrfs_get_tree_mod_seq(struct btrfs_fs_info *fs_info, |
| 373 | struct seq_list *elem) |
| 374 | { |
| 375 | u64 seq; |
| 376 | |
| 377 | tree_mod_log_write_lock(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 378 | spin_lock(&fs_info->tree_mod_seq_lock); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 379 | if (!elem->seq) { |
| 380 | elem->seq = btrfs_inc_tree_mod_seq(fs_info); |
| 381 | list_add_tail(&elem->list, &fs_info->tree_mod_seq_list); |
| 382 | } |
| 383 | seq = btrfs_inc_tree_mod_seq(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 384 | spin_unlock(&fs_info->tree_mod_seq_lock); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 385 | tree_mod_log_write_unlock(fs_info); |
| 386 | |
| 387 | return seq; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 388 | } |
| 389 | |
| 390 | void btrfs_put_tree_mod_seq(struct btrfs_fs_info *fs_info, |
| 391 | struct seq_list *elem) |
| 392 | { |
| 393 | struct rb_root *tm_root; |
| 394 | struct rb_node *node; |
| 395 | struct rb_node *next; |
| 396 | struct seq_list *cur_elem; |
| 397 | struct tree_mod_elem *tm; |
| 398 | u64 min_seq = (u64)-1; |
| 399 | u64 seq_putting = elem->seq; |
| 400 | |
| 401 | if (!seq_putting) |
| 402 | return; |
| 403 | |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 404 | spin_lock(&fs_info->tree_mod_seq_lock); |
| 405 | list_del(&elem->list); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 406 | elem->seq = 0; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 407 | |
| 408 | list_for_each_entry(cur_elem, &fs_info->tree_mod_seq_list, list) { |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 409 | if (cur_elem->seq < min_seq) { |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 410 | if (seq_putting > cur_elem->seq) { |
| 411 | /* |
| 412 | * blocker with lower sequence number exists, we |
| 413 | * cannot remove anything from the log |
| 414 | */ |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 415 | spin_unlock(&fs_info->tree_mod_seq_lock); |
| 416 | return; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 417 | } |
| 418 | min_seq = cur_elem->seq; |
| 419 | } |
| 420 | } |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 421 | spin_unlock(&fs_info->tree_mod_seq_lock); |
| 422 | |
| 423 | /* |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 424 | * anything that's lower than the lowest existing (read: blocked) |
| 425 | * sequence number can be removed from the tree. |
| 426 | */ |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 427 | tree_mod_log_write_lock(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 428 | tm_root = &fs_info->tree_mod_log; |
| 429 | for (node = rb_first(tm_root); node; node = next) { |
| 430 | next = rb_next(node); |
| 431 | tm = container_of(node, struct tree_mod_elem, node); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 432 | if (tm->seq > min_seq) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 433 | continue; |
| 434 | rb_erase(node, tm_root); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 435 | kfree(tm); |
| 436 | } |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 437 | tree_mod_log_write_unlock(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 438 | } |
| 439 | |
| 440 | /* |
| 441 | * key order of the log: |
| 442 | * index -> sequence |
| 443 | * |
| 444 | * the index is the shifted logical of the *new* root node for root replace |
| 445 | * operations, or the shifted logical of the affected block for all other |
| 446 | * operations. |
| 447 | */ |
| 448 | static noinline int |
| 449 | __tree_mod_log_insert(struct btrfs_fs_info *fs_info, struct tree_mod_elem *tm) |
| 450 | { |
| 451 | struct rb_root *tm_root; |
| 452 | struct rb_node **new; |
| 453 | struct rb_node *parent = NULL; |
| 454 | struct tree_mod_elem *cur; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 455 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 456 | BUG_ON(!tm || !tm->seq); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 457 | |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 458 | tm_root = &fs_info->tree_mod_log; |
| 459 | new = &tm_root->rb_node; |
| 460 | while (*new) { |
| 461 | cur = container_of(*new, struct tree_mod_elem, node); |
| 462 | parent = *new; |
| 463 | if (cur->index < tm->index) |
| 464 | new = &((*new)->rb_left); |
| 465 | else if (cur->index > tm->index) |
| 466 | new = &((*new)->rb_right); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 467 | else if (cur->seq < tm->seq) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 468 | new = &((*new)->rb_left); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 469 | else if (cur->seq > tm->seq) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 470 | new = &((*new)->rb_right); |
| 471 | else { |
| 472 | kfree(tm); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 473 | return -EEXIST; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 474 | } |
| 475 | } |
| 476 | |
| 477 | rb_link_node(&tm->node, parent, new); |
| 478 | rb_insert_color(&tm->node, tm_root); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 479 | return 0; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 480 | } |
| 481 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 482 | /* |
| 483 | * Determines if logging can be omitted. Returns 1 if it can. Otherwise, it |
| 484 | * returns zero with the tree_mod_log_lock acquired. The caller must hold |
| 485 | * this until all tree mod log insertions are recorded in the rb tree and then |
| 486 | * call tree_mod_log_write_unlock() to release. |
| 487 | */ |
Jan Schmidt | e9b7fd4 | 2012-05-31 14:59:09 +0200 | [diff] [blame] | 488 | static inline int tree_mod_dont_log(struct btrfs_fs_info *fs_info, |
| 489 | struct extent_buffer *eb) { |
| 490 | smp_mb(); |
| 491 | if (list_empty(&(fs_info)->tree_mod_seq_list)) |
| 492 | return 1; |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 493 | if (eb && btrfs_header_level(eb) == 0) |
Jan Schmidt | e9b7fd4 | 2012-05-31 14:59:09 +0200 | [diff] [blame] | 494 | return 1; |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 495 | |
| 496 | tree_mod_log_write_lock(fs_info); |
| 497 | if (list_empty(&fs_info->tree_mod_seq_list)) { |
| 498 | /* |
| 499 | * someone emptied the list while we were waiting for the lock. |
| 500 | * we must not add to the list when no blocker exists. |
| 501 | */ |
| 502 | tree_mod_log_write_unlock(fs_info); |
| 503 | return 1; |
| 504 | } |
| 505 | |
Jan Schmidt | e9b7fd4 | 2012-05-31 14:59:09 +0200 | [diff] [blame] | 506 | return 0; |
| 507 | } |
| 508 | |
Jan Schmidt | 3310c36 | 2012-06-11 10:52:38 +0200 | [diff] [blame] | 509 | /* |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 510 | * This allocates memory and gets a tree modification sequence number. |
Jan Schmidt | 3310c36 | 2012-06-11 10:52:38 +0200 | [diff] [blame] | 511 | * |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 512 | * Returns <0 on error. |
| 513 | * Returns >0 (the added sequence number) on success. |
Jan Schmidt | 3310c36 | 2012-06-11 10:52:38 +0200 | [diff] [blame] | 514 | */ |
Jan Schmidt | 926dd8a | 2012-05-31 14:00:15 +0200 | [diff] [blame] | 515 | static inline int tree_mod_alloc(struct btrfs_fs_info *fs_info, gfp_t flags, |
| 516 | struct tree_mod_elem **tm_ret) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 517 | { |
| 518 | struct tree_mod_elem *tm; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 519 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 520 | /* |
| 521 | * once we switch from spin locks to something different, we should |
| 522 | * honor the flags parameter here. |
| 523 | */ |
| 524 | tm = *tm_ret = kzalloc(sizeof(*tm), GFP_ATOMIC); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 525 | if (!tm) |
| 526 | return -ENOMEM; |
| 527 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 528 | tm->seq = btrfs_inc_tree_mod_seq(fs_info); |
| 529 | return tm->seq; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 530 | } |
| 531 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 532 | static inline int |
| 533 | __tree_mod_log_insert_key(struct btrfs_fs_info *fs_info, |
| 534 | struct extent_buffer *eb, int slot, |
| 535 | enum mod_log_op op, gfp_t flags) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 536 | { |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 537 | int ret; |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 538 | struct tree_mod_elem *tm; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 539 | |
| 540 | ret = tree_mod_alloc(fs_info, flags, &tm); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 541 | if (ret < 0) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 542 | return ret; |
| 543 | |
| 544 | tm->index = eb->start >> PAGE_CACHE_SHIFT; |
| 545 | if (op != MOD_LOG_KEY_ADD) { |
| 546 | btrfs_node_key(eb, &tm->key, slot); |
| 547 | tm->blockptr = btrfs_node_blockptr(eb, slot); |
| 548 | } |
| 549 | tm->op = op; |
| 550 | tm->slot = slot; |
| 551 | tm->generation = btrfs_node_ptr_generation(eb, slot); |
| 552 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 553 | return __tree_mod_log_insert(fs_info, tm); |
| 554 | } |
| 555 | |
| 556 | static noinline int |
| 557 | tree_mod_log_insert_key_mask(struct btrfs_fs_info *fs_info, |
| 558 | struct extent_buffer *eb, int slot, |
| 559 | enum mod_log_op op, gfp_t flags) |
| 560 | { |
| 561 | int ret; |
| 562 | |
| 563 | if (tree_mod_dont_log(fs_info, eb)) |
| 564 | return 0; |
| 565 | |
| 566 | ret = __tree_mod_log_insert_key(fs_info, eb, slot, op, flags); |
| 567 | |
| 568 | tree_mod_log_write_unlock(fs_info); |
Jan Schmidt | 3310c36 | 2012-06-11 10:52:38 +0200 | [diff] [blame] | 569 | return ret; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 570 | } |
| 571 | |
| 572 | static noinline int |
| 573 | tree_mod_log_insert_key(struct btrfs_fs_info *fs_info, struct extent_buffer *eb, |
| 574 | int slot, enum mod_log_op op) |
| 575 | { |
| 576 | return tree_mod_log_insert_key_mask(fs_info, eb, slot, op, GFP_NOFS); |
| 577 | } |
| 578 | |
| 579 | static noinline int |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 580 | tree_mod_log_insert_key_locked(struct btrfs_fs_info *fs_info, |
| 581 | struct extent_buffer *eb, int slot, |
| 582 | enum mod_log_op op) |
| 583 | { |
| 584 | return __tree_mod_log_insert_key(fs_info, eb, slot, op, GFP_NOFS); |
| 585 | } |
| 586 | |
| 587 | static noinline int |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 588 | tree_mod_log_insert_move(struct btrfs_fs_info *fs_info, |
| 589 | struct extent_buffer *eb, int dst_slot, int src_slot, |
| 590 | int nr_items, gfp_t flags) |
| 591 | { |
| 592 | struct tree_mod_elem *tm; |
| 593 | int ret; |
| 594 | int i; |
| 595 | |
Jan Schmidt | f395694 | 2012-05-31 15:02:32 +0200 | [diff] [blame] | 596 | if (tree_mod_dont_log(fs_info, eb)) |
| 597 | return 0; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 598 | |
| 599 | for (i = 0; i + dst_slot < src_slot && i < nr_items; i++) { |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 600 | ret = tree_mod_log_insert_key_locked(fs_info, eb, i + dst_slot, |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 601 | MOD_LOG_KEY_REMOVE_WHILE_MOVING); |
| 602 | BUG_ON(ret < 0); |
| 603 | } |
| 604 | |
Jan Schmidt | f395694 | 2012-05-31 15:02:32 +0200 | [diff] [blame] | 605 | ret = tree_mod_alloc(fs_info, flags, &tm); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 606 | if (ret < 0) |
| 607 | goto out; |
Jan Schmidt | f395694 | 2012-05-31 15:02:32 +0200 | [diff] [blame] | 608 | |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 609 | tm->index = eb->start >> PAGE_CACHE_SHIFT; |
| 610 | tm->slot = src_slot; |
| 611 | tm->move.dst_slot = dst_slot; |
| 612 | tm->move.nr_items = nr_items; |
| 613 | tm->op = MOD_LOG_MOVE_KEYS; |
| 614 | |
Jan Schmidt | 3310c36 | 2012-06-11 10:52:38 +0200 | [diff] [blame] | 615 | ret = __tree_mod_log_insert(fs_info, tm); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 616 | out: |
| 617 | tree_mod_log_write_unlock(fs_info); |
Jan Schmidt | 3310c36 | 2012-06-11 10:52:38 +0200 | [diff] [blame] | 618 | return ret; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 619 | } |
| 620 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 621 | static inline void |
| 622 | __tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb) |
| 623 | { |
| 624 | int i; |
| 625 | u32 nritems; |
| 626 | int ret; |
| 627 | |
Chris Mason | b12a3b1 | 2012-08-07 15:34:49 -0400 | [diff] [blame] | 628 | if (btrfs_header_level(eb) == 0) |
| 629 | return; |
| 630 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 631 | nritems = btrfs_header_nritems(eb); |
| 632 | for (i = nritems - 1; i >= 0; i--) { |
| 633 | ret = tree_mod_log_insert_key_locked(fs_info, eb, i, |
| 634 | MOD_LOG_KEY_REMOVE_WHILE_FREEING); |
| 635 | BUG_ON(ret < 0); |
| 636 | } |
| 637 | } |
| 638 | |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 639 | static noinline int |
| 640 | tree_mod_log_insert_root(struct btrfs_fs_info *fs_info, |
| 641 | struct extent_buffer *old_root, |
| 642 | struct extent_buffer *new_root, gfp_t flags) |
| 643 | { |
| 644 | struct tree_mod_elem *tm; |
| 645 | int ret; |
| 646 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 647 | if (tree_mod_dont_log(fs_info, NULL)) |
| 648 | return 0; |
| 649 | |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 650 | ret = tree_mod_alloc(fs_info, flags, &tm); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 651 | if (ret < 0) |
| 652 | goto out; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 653 | |
| 654 | tm->index = new_root->start >> PAGE_CACHE_SHIFT; |
| 655 | tm->old_root.logical = old_root->start; |
| 656 | tm->old_root.level = btrfs_header_level(old_root); |
| 657 | tm->generation = btrfs_header_generation(old_root); |
| 658 | tm->op = MOD_LOG_ROOT_REPLACE; |
| 659 | |
Jan Schmidt | 3310c36 | 2012-06-11 10:52:38 +0200 | [diff] [blame] | 660 | ret = __tree_mod_log_insert(fs_info, tm); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 661 | out: |
| 662 | tree_mod_log_write_unlock(fs_info); |
Jan Schmidt | 3310c36 | 2012-06-11 10:52:38 +0200 | [diff] [blame] | 663 | return ret; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 664 | } |
| 665 | |
| 666 | static struct tree_mod_elem * |
| 667 | __tree_mod_log_search(struct btrfs_fs_info *fs_info, u64 start, u64 min_seq, |
| 668 | int smallest) |
| 669 | { |
| 670 | struct rb_root *tm_root; |
| 671 | struct rb_node *node; |
| 672 | struct tree_mod_elem *cur = NULL; |
| 673 | struct tree_mod_elem *found = NULL; |
| 674 | u64 index = start >> PAGE_CACHE_SHIFT; |
| 675 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 676 | tree_mod_log_read_lock(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 677 | tm_root = &fs_info->tree_mod_log; |
| 678 | node = tm_root->rb_node; |
| 679 | while (node) { |
| 680 | cur = container_of(node, struct tree_mod_elem, node); |
| 681 | if (cur->index < index) { |
| 682 | node = node->rb_left; |
| 683 | } else if (cur->index > index) { |
| 684 | node = node->rb_right; |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 685 | } else if (cur->seq < min_seq) { |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 686 | node = node->rb_left; |
| 687 | } else if (!smallest) { |
| 688 | /* we want the node with the highest seq */ |
| 689 | if (found) |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 690 | BUG_ON(found->seq > cur->seq); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 691 | found = cur; |
| 692 | node = node->rb_left; |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 693 | } else if (cur->seq > min_seq) { |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 694 | /* we want the node with the smallest seq */ |
| 695 | if (found) |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 696 | BUG_ON(found->seq < cur->seq); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 697 | found = cur; |
| 698 | node = node->rb_right; |
| 699 | } else { |
| 700 | found = cur; |
| 701 | break; |
| 702 | } |
| 703 | } |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 704 | tree_mod_log_read_unlock(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 705 | |
| 706 | return found; |
| 707 | } |
| 708 | |
| 709 | /* |
| 710 | * this returns the element from the log with the smallest time sequence |
| 711 | * value that's in the log (the oldest log item). any element with a time |
| 712 | * sequence lower than min_seq will be ignored. |
| 713 | */ |
| 714 | static struct tree_mod_elem * |
| 715 | tree_mod_log_search_oldest(struct btrfs_fs_info *fs_info, u64 start, |
| 716 | u64 min_seq) |
| 717 | { |
| 718 | return __tree_mod_log_search(fs_info, start, min_seq, 1); |
| 719 | } |
| 720 | |
| 721 | /* |
| 722 | * this returns the element from the log with the largest time sequence |
| 723 | * value that's in the log (the most recent log item). any element with |
| 724 | * a time sequence lower than min_seq will be ignored. |
| 725 | */ |
| 726 | static struct tree_mod_elem * |
| 727 | tree_mod_log_search(struct btrfs_fs_info *fs_info, u64 start, u64 min_seq) |
| 728 | { |
| 729 | return __tree_mod_log_search(fs_info, start, min_seq, 0); |
| 730 | } |
| 731 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 732 | static noinline void |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 733 | tree_mod_log_eb_copy(struct btrfs_fs_info *fs_info, struct extent_buffer *dst, |
| 734 | struct extent_buffer *src, unsigned long dst_offset, |
| 735 | unsigned long src_offset, int nr_items) |
| 736 | { |
| 737 | int ret; |
| 738 | int i; |
| 739 | |
Jan Schmidt | e9b7fd4 | 2012-05-31 14:59:09 +0200 | [diff] [blame] | 740 | if (tree_mod_dont_log(fs_info, NULL)) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 741 | return; |
| 742 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 743 | if (btrfs_header_level(dst) == 0 && btrfs_header_level(src) == 0) { |
| 744 | tree_mod_log_write_unlock(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 745 | return; |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 746 | } |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 747 | |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 748 | for (i = 0; i < nr_items; i++) { |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 749 | ret = tree_mod_log_insert_key_locked(fs_info, src, |
| 750 | i + src_offset, |
| 751 | MOD_LOG_KEY_REMOVE); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 752 | BUG_ON(ret < 0); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 753 | ret = tree_mod_log_insert_key_locked(fs_info, dst, |
| 754 | i + dst_offset, |
| 755 | MOD_LOG_KEY_ADD); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 756 | BUG_ON(ret < 0); |
| 757 | } |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 758 | |
| 759 | tree_mod_log_write_unlock(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 760 | } |
| 761 | |
| 762 | static inline void |
| 763 | tree_mod_log_eb_move(struct btrfs_fs_info *fs_info, struct extent_buffer *dst, |
| 764 | int dst_offset, int src_offset, int nr_items) |
| 765 | { |
| 766 | int ret; |
| 767 | ret = tree_mod_log_insert_move(fs_info, dst, dst_offset, src_offset, |
| 768 | nr_items, GFP_NOFS); |
| 769 | BUG_ON(ret < 0); |
| 770 | } |
| 771 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 772 | static noinline void |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 773 | tree_mod_log_set_node_key(struct btrfs_fs_info *fs_info, |
| 774 | struct extent_buffer *eb, |
| 775 | struct btrfs_disk_key *disk_key, int slot, int atomic) |
| 776 | { |
| 777 | int ret; |
| 778 | |
| 779 | ret = tree_mod_log_insert_key_mask(fs_info, eb, slot, |
| 780 | MOD_LOG_KEY_REPLACE, |
| 781 | atomic ? GFP_ATOMIC : GFP_NOFS); |
| 782 | BUG_ON(ret < 0); |
| 783 | } |
| 784 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 785 | static noinline void |
| 786 | tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 787 | { |
Jan Schmidt | e9b7fd4 | 2012-05-31 14:59:09 +0200 | [diff] [blame] | 788 | if (tree_mod_dont_log(fs_info, eb)) |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 789 | return; |
| 790 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 791 | __tree_mod_log_free_eb(fs_info, eb); |
| 792 | |
| 793 | tree_mod_log_write_unlock(fs_info); |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 794 | } |
| 795 | |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 796 | static noinline void |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 797 | tree_mod_log_set_root_pointer(struct btrfs_root *root, |
| 798 | struct extent_buffer *new_root_node) |
| 799 | { |
| 800 | int ret; |
Jan Schmidt | bd989ba | 2012-05-16 17:18:50 +0200 | [diff] [blame] | 801 | ret = tree_mod_log_insert_root(root->fs_info, root->node, |
| 802 | new_root_node, GFP_NOFS); |
| 803 | BUG_ON(ret < 0); |
| 804 | } |
| 805 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 806 | /* |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 807 | * check if the tree block can be shared by multiple trees |
| 808 | */ |
| 809 | int btrfs_block_can_be_shared(struct btrfs_root *root, |
| 810 | struct extent_buffer *buf) |
| 811 | { |
| 812 | /* |
| 813 | * Tree blocks not in refernece counted trees and tree roots |
| 814 | * are never shared. If a block was allocated after the last |
| 815 | * snapshot and the block was not allocated by tree relocation, |
| 816 | * we know the block is not shared. |
| 817 | */ |
| 818 | if (root->ref_cows && |
| 819 | buf != root->node && buf != root->commit_root && |
| 820 | (btrfs_header_generation(buf) <= |
| 821 | btrfs_root_last_snapshot(&root->root_item) || |
| 822 | btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))) |
| 823 | return 1; |
| 824 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 |
| 825 | if (root->ref_cows && |
| 826 | btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV) |
| 827 | return 1; |
| 828 | #endif |
| 829 | return 0; |
| 830 | } |
| 831 | |
| 832 | static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, |
| 833 | struct btrfs_root *root, |
| 834 | struct extent_buffer *buf, |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 835 | struct extent_buffer *cow, |
| 836 | int *last_ref) |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 837 | { |
| 838 | u64 refs; |
| 839 | u64 owner; |
| 840 | u64 flags; |
| 841 | u64 new_flags = 0; |
| 842 | int ret; |
| 843 | |
| 844 | /* |
| 845 | * Backrefs update rules: |
| 846 | * |
| 847 | * Always use full backrefs for extent pointers in tree block |
| 848 | * allocated by tree relocation. |
| 849 | * |
| 850 | * If a shared tree block is no longer referenced by its owner |
| 851 | * tree (btrfs_header_owner(buf) == root->root_key.objectid), |
| 852 | * use full backrefs for extent pointers in tree block. |
| 853 | * |
| 854 | * If a tree block is been relocating |
| 855 | * (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID), |
| 856 | * use full backrefs for extent pointers in tree block. |
| 857 | * The reason for this is some operations (such as drop tree) |
| 858 | * are only allowed for blocks use full backrefs. |
| 859 | */ |
| 860 | |
| 861 | if (btrfs_block_can_be_shared(root, buf)) { |
| 862 | ret = btrfs_lookup_extent_info(trans, root, buf->start, |
| 863 | buf->len, &refs, &flags); |
Mark Fasheh | be1a556 | 2011-08-08 13:20:18 -0700 | [diff] [blame] | 864 | if (ret) |
| 865 | return ret; |
Mark Fasheh | e5df957 | 2011-08-29 14:17:04 -0700 | [diff] [blame] | 866 | if (refs == 0) { |
| 867 | ret = -EROFS; |
| 868 | btrfs_std_error(root->fs_info, ret); |
| 869 | return ret; |
| 870 | } |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 871 | } else { |
| 872 | refs = 1; |
| 873 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID || |
| 874 | btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV) |
| 875 | flags = BTRFS_BLOCK_FLAG_FULL_BACKREF; |
| 876 | else |
| 877 | flags = 0; |
| 878 | } |
| 879 | |
| 880 | owner = btrfs_header_owner(buf); |
| 881 | BUG_ON(owner == BTRFS_TREE_RELOC_OBJECTID && |
| 882 | !(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)); |
| 883 | |
| 884 | if (refs > 1) { |
| 885 | if ((owner == root->root_key.objectid || |
| 886 | root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) && |
| 887 | !(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) { |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 888 | ret = btrfs_inc_ref(trans, root, buf, 1, 1); |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 889 | BUG_ON(ret); /* -ENOMEM */ |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 890 | |
| 891 | if (root->root_key.objectid == |
| 892 | BTRFS_TREE_RELOC_OBJECTID) { |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 893 | ret = btrfs_dec_ref(trans, root, buf, 0, 1); |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 894 | BUG_ON(ret); /* -ENOMEM */ |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 895 | ret = btrfs_inc_ref(trans, root, cow, 1, 1); |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 896 | BUG_ON(ret); /* -ENOMEM */ |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 897 | } |
| 898 | new_flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF; |
| 899 | } else { |
| 900 | |
| 901 | if (root->root_key.objectid == |
| 902 | BTRFS_TREE_RELOC_OBJECTID) |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 903 | ret = btrfs_inc_ref(trans, root, cow, 1, 1); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 904 | else |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 905 | ret = btrfs_inc_ref(trans, root, cow, 0, 1); |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 906 | BUG_ON(ret); /* -ENOMEM */ |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 907 | } |
| 908 | if (new_flags != 0) { |
| 909 | ret = btrfs_set_disk_extent_flags(trans, root, |
| 910 | buf->start, |
| 911 | buf->len, |
| 912 | new_flags, 0); |
Mark Fasheh | be1a556 | 2011-08-08 13:20:18 -0700 | [diff] [blame] | 913 | if (ret) |
| 914 | return ret; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 915 | } |
| 916 | } else { |
| 917 | if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) { |
| 918 | if (root->root_key.objectid == |
| 919 | BTRFS_TREE_RELOC_OBJECTID) |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 920 | ret = btrfs_inc_ref(trans, root, cow, 1, 1); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 921 | else |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 922 | ret = btrfs_inc_ref(trans, root, cow, 0, 1); |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 923 | BUG_ON(ret); /* -ENOMEM */ |
Arne Jansen | 66d7e7f | 2011-09-12 15:26:38 +0200 | [diff] [blame] | 924 | ret = btrfs_dec_ref(trans, root, buf, 1, 1); |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 925 | BUG_ON(ret); /* -ENOMEM */ |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 926 | } |
Jan Schmidt | ba1bfbd | 2012-10-22 20:02:56 +0200 | [diff] [blame^] | 927 | tree_mod_log_free_eb(root->fs_info, buf); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 928 | clean_tree_block(trans, root, buf); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 929 | *last_ref = 1; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 930 | } |
| 931 | return 0; |
| 932 | } |
| 933 | |
| 934 | /* |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 935 | * does the dirty work in cow of a single block. The parent block (if |
| 936 | * supplied) is updated to point to the new cow copy. The new buffer is marked |
| 937 | * dirty and returned locked. If you modify the block it needs to be marked |
| 938 | * dirty again. |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 939 | * |
| 940 | * search_start -- an allocation hint for the new block |
| 941 | * |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 942 | * empty_size -- a hint that you plan on doing more cow. This is the size in |
| 943 | * bytes the allocator should try to find free next to the block it returns. |
| 944 | * This is just a hint and may be ignored by the allocator. |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 945 | */ |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 946 | static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 947 | struct btrfs_root *root, |
| 948 | struct extent_buffer *buf, |
| 949 | struct extent_buffer *parent, int parent_slot, |
| 950 | struct extent_buffer **cow_ret, |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 951 | u64 search_start, u64 empty_size) |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 952 | { |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 953 | struct btrfs_disk_key disk_key; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 954 | struct extent_buffer *cow; |
Mark Fasheh | be1a556 | 2011-08-08 13:20:18 -0700 | [diff] [blame] | 955 | int level, ret; |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 956 | int last_ref = 0; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 957 | int unlock_orig = 0; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 958 | u64 parent_start; |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 959 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 960 | if (*cow_ret == buf) |
| 961 | unlock_orig = 1; |
| 962 | |
Chris Mason | b9447ef | 2009-03-09 11:45:38 -0400 | [diff] [blame] | 963 | btrfs_assert_tree_locked(buf); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 964 | |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 965 | WARN_ON(root->ref_cows && trans->transid != |
| 966 | root->fs_info->running_transaction->transid); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 967 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 968 | |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 969 | level = btrfs_header_level(buf); |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 970 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 971 | if (level == 0) |
| 972 | btrfs_item_key(buf, &disk_key, 0); |
| 973 | else |
| 974 | btrfs_node_key(buf, &disk_key, 0); |
| 975 | |
| 976 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { |
| 977 | if (parent) |
| 978 | parent_start = parent->start; |
| 979 | else |
| 980 | parent_start = 0; |
| 981 | } else |
| 982 | parent_start = 0; |
| 983 | |
| 984 | cow = btrfs_alloc_free_block(trans, root, buf->len, parent_start, |
| 985 | root->root_key.objectid, &disk_key, |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 986 | level, search_start, empty_size); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 987 | if (IS_ERR(cow)) |
| 988 | return PTR_ERR(cow); |
| 989 | |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 990 | /* cow is set to blocking by btrfs_init_new_buffer */ |
| 991 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 992 | copy_extent_buffer(cow, buf, 0, 0, cow->len); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 993 | btrfs_set_header_bytenr(cow, cow->start); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 994 | btrfs_set_header_generation(cow, trans->transid); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 995 | btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV); |
| 996 | btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN | |
| 997 | BTRFS_HEADER_FLAG_RELOC); |
| 998 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) |
| 999 | btrfs_set_header_flag(cow, BTRFS_HEADER_FLAG_RELOC); |
| 1000 | else |
| 1001 | btrfs_set_header_owner(cow, root->root_key.objectid); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1002 | |
Yan Zheng | 2b82032 | 2008-11-17 21:11:30 -0500 | [diff] [blame] | 1003 | write_extent_buffer(cow, root->fs_info->fsid, |
| 1004 | (unsigned long)btrfs_header_fsid(cow), |
| 1005 | BTRFS_FSID_SIZE); |
| 1006 | |
Mark Fasheh | be1a556 | 2011-08-08 13:20:18 -0700 | [diff] [blame] | 1007 | ret = update_ref_for_cow(trans, root, buf, cow, &last_ref); |
Mark Fasheh | b68dc2a | 2011-08-29 14:30:39 -0700 | [diff] [blame] | 1008 | if (ret) { |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 1009 | btrfs_abort_transaction(trans, root, ret); |
Mark Fasheh | b68dc2a | 2011-08-29 14:30:39 -0700 | [diff] [blame] | 1010 | return ret; |
| 1011 | } |
Zheng Yan | 1a40e23 | 2008-09-26 10:09:34 -0400 | [diff] [blame] | 1012 | |
Yan, Zheng | 3fd0a55 | 2010-05-16 10:49:59 -0400 | [diff] [blame] | 1013 | if (root->ref_cows) |
| 1014 | btrfs_reloc_cow_block(trans, root, buf, cow); |
| 1015 | |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1016 | if (buf == root->node) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1017 | WARN_ON(parent && parent != buf); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 1018 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID || |
| 1019 | btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV) |
| 1020 | parent_start = buf->start; |
| 1021 | else |
| 1022 | parent_start = 0; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1023 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1024 | extent_buffer_get(cow); |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 1025 | tree_mod_log_set_root_pointer(root, cow); |
Chris Mason | 240f62c | 2011-03-23 14:54:42 -0400 | [diff] [blame] | 1026 | rcu_assign_pointer(root->node, cow); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1027 | |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1028 | btrfs_free_tree_block(trans, root, buf, parent_start, |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 1029 | last_ref); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1030 | free_extent_buffer(buf); |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 1031 | add_root_to_dirty_list(root); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1032 | } else { |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 1033 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) |
| 1034 | parent_start = parent->start; |
| 1035 | else |
| 1036 | parent_start = 0; |
| 1037 | |
| 1038 | WARN_ON(trans->transid != btrfs_header_generation(parent)); |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 1039 | tree_mod_log_insert_key(root->fs_info, parent, parent_slot, |
| 1040 | MOD_LOG_KEY_REPLACE); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1041 | btrfs_set_node_blockptr(parent, parent_slot, |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 1042 | cow->start); |
Chris Mason | 74493f7 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 1043 | btrfs_set_node_ptr_generation(parent, parent_slot, |
| 1044 | trans->transid); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1045 | btrfs_mark_buffer_dirty(parent); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1046 | btrfs_free_tree_block(trans, root, buf, parent_start, |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 1047 | last_ref); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1048 | } |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1049 | if (unlock_orig) |
| 1050 | btrfs_tree_unlock(buf); |
Josef Bacik | 3083ee2 | 2012-03-09 16:01:49 -0500 | [diff] [blame] | 1051 | free_extent_buffer_stale(buf); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1052 | btrfs_mark_buffer_dirty(cow); |
| 1053 | *cow_ret = cow; |
| 1054 | return 0; |
| 1055 | } |
| 1056 | |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1057 | /* |
| 1058 | * returns the logical address of the oldest predecessor of the given root. |
| 1059 | * entries older than time_seq are ignored. |
| 1060 | */ |
| 1061 | static struct tree_mod_elem * |
| 1062 | __tree_mod_log_oldest_root(struct btrfs_fs_info *fs_info, |
| 1063 | struct btrfs_root *root, u64 time_seq) |
| 1064 | { |
| 1065 | struct tree_mod_elem *tm; |
| 1066 | struct tree_mod_elem *found = NULL; |
| 1067 | u64 root_logical = root->node->start; |
| 1068 | int looped = 0; |
| 1069 | |
| 1070 | if (!time_seq) |
| 1071 | return 0; |
| 1072 | |
| 1073 | /* |
| 1074 | * the very last operation that's logged for a root is the replacement |
| 1075 | * operation (if it is replaced at all). this has the index of the *new* |
| 1076 | * root, making it the very first operation that's logged for this root. |
| 1077 | */ |
| 1078 | while (1) { |
| 1079 | tm = tree_mod_log_search_oldest(fs_info, root_logical, |
| 1080 | time_seq); |
| 1081 | if (!looped && !tm) |
| 1082 | return 0; |
| 1083 | /* |
Jan Schmidt | 28da9fb | 2012-06-21 10:59:13 +0200 | [diff] [blame] | 1084 | * if there are no tree operation for the oldest root, we simply |
| 1085 | * return it. this should only happen if that (old) root is at |
| 1086 | * level 0. |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1087 | */ |
Jan Schmidt | 28da9fb | 2012-06-21 10:59:13 +0200 | [diff] [blame] | 1088 | if (!tm) |
| 1089 | break; |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1090 | |
Jan Schmidt | 28da9fb | 2012-06-21 10:59:13 +0200 | [diff] [blame] | 1091 | /* |
| 1092 | * if there's an operation that's not a root replacement, we |
| 1093 | * found the oldest version of our root. normally, we'll find a |
| 1094 | * MOD_LOG_KEY_REMOVE_WHILE_FREEING operation here. |
| 1095 | */ |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1096 | if (tm->op != MOD_LOG_ROOT_REPLACE) |
| 1097 | break; |
| 1098 | |
| 1099 | found = tm; |
| 1100 | root_logical = tm->old_root.logical; |
| 1101 | BUG_ON(root_logical == root->node->start); |
| 1102 | looped = 1; |
| 1103 | } |
| 1104 | |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1105 | /* if there's no old root to return, return what we found instead */ |
| 1106 | if (!found) |
| 1107 | found = tm; |
| 1108 | |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1109 | return found; |
| 1110 | } |
| 1111 | |
| 1112 | /* |
| 1113 | * tm is a pointer to the first operation to rewind within eb. then, all |
| 1114 | * previous operations will be rewinded (until we reach something older than |
| 1115 | * time_seq). |
| 1116 | */ |
| 1117 | static void |
| 1118 | __tree_mod_log_rewind(struct extent_buffer *eb, u64 time_seq, |
| 1119 | struct tree_mod_elem *first_tm) |
| 1120 | { |
| 1121 | u32 n; |
| 1122 | struct rb_node *next; |
| 1123 | struct tree_mod_elem *tm = first_tm; |
| 1124 | unsigned long o_dst; |
| 1125 | unsigned long o_src; |
| 1126 | unsigned long p_size = sizeof(struct btrfs_key_ptr); |
| 1127 | |
| 1128 | n = btrfs_header_nritems(eb); |
Jan Schmidt | 097b8a7 | 2012-06-21 11:08:04 +0200 | [diff] [blame] | 1129 | while (tm && tm->seq >= time_seq) { |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1130 | /* |
| 1131 | * all the operations are recorded with the operator used for |
| 1132 | * the modification. as we're going backwards, we do the |
| 1133 | * opposite of each operation here. |
| 1134 | */ |
| 1135 | switch (tm->op) { |
| 1136 | case MOD_LOG_KEY_REMOVE_WHILE_FREEING: |
| 1137 | BUG_ON(tm->slot < n); |
| 1138 | case MOD_LOG_KEY_REMOVE_WHILE_MOVING: |
| 1139 | case MOD_LOG_KEY_REMOVE: |
| 1140 | btrfs_set_node_key(eb, &tm->key, tm->slot); |
| 1141 | btrfs_set_node_blockptr(eb, tm->slot, tm->blockptr); |
| 1142 | btrfs_set_node_ptr_generation(eb, tm->slot, |
| 1143 | tm->generation); |
| 1144 | n++; |
| 1145 | break; |
| 1146 | case MOD_LOG_KEY_REPLACE: |
| 1147 | BUG_ON(tm->slot >= n); |
| 1148 | btrfs_set_node_key(eb, &tm->key, tm->slot); |
| 1149 | btrfs_set_node_blockptr(eb, tm->slot, tm->blockptr); |
| 1150 | btrfs_set_node_ptr_generation(eb, tm->slot, |
| 1151 | tm->generation); |
| 1152 | break; |
| 1153 | case MOD_LOG_KEY_ADD: |
Jan Schmidt | 19956c7 | 2012-06-22 14:52:13 +0200 | [diff] [blame] | 1154 | /* if a move operation is needed it's in the log */ |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1155 | n--; |
| 1156 | break; |
| 1157 | case MOD_LOG_MOVE_KEYS: |
Jan Schmidt | c319310 | 2012-05-31 19:24:36 +0200 | [diff] [blame] | 1158 | o_dst = btrfs_node_key_ptr_offset(tm->slot); |
| 1159 | o_src = btrfs_node_key_ptr_offset(tm->move.dst_slot); |
| 1160 | memmove_extent_buffer(eb, o_dst, o_src, |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1161 | tm->move.nr_items * p_size); |
| 1162 | break; |
| 1163 | case MOD_LOG_ROOT_REPLACE: |
| 1164 | /* |
| 1165 | * this operation is special. for roots, this must be |
| 1166 | * handled explicitly before rewinding. |
| 1167 | * for non-roots, this operation may exist if the node |
| 1168 | * was a root: root A -> child B; then A gets empty and |
| 1169 | * B is promoted to the new root. in the mod log, we'll |
| 1170 | * have a root-replace operation for B, a tree block |
| 1171 | * that is no root. we simply ignore that operation. |
| 1172 | */ |
| 1173 | break; |
| 1174 | } |
| 1175 | next = rb_next(&tm->node); |
| 1176 | if (!next) |
| 1177 | break; |
| 1178 | tm = container_of(next, struct tree_mod_elem, node); |
| 1179 | if (tm->index != first_tm->index) |
| 1180 | break; |
| 1181 | } |
| 1182 | btrfs_set_header_nritems(eb, n); |
| 1183 | } |
| 1184 | |
| 1185 | static struct extent_buffer * |
| 1186 | tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb, |
| 1187 | u64 time_seq) |
| 1188 | { |
| 1189 | struct extent_buffer *eb_rewin; |
| 1190 | struct tree_mod_elem *tm; |
| 1191 | |
| 1192 | if (!time_seq) |
| 1193 | return eb; |
| 1194 | |
| 1195 | if (btrfs_header_level(eb) == 0) |
| 1196 | return eb; |
| 1197 | |
| 1198 | tm = tree_mod_log_search(fs_info, eb->start, time_seq); |
| 1199 | if (!tm) |
| 1200 | return eb; |
| 1201 | |
| 1202 | if (tm->op == MOD_LOG_KEY_REMOVE_WHILE_FREEING) { |
| 1203 | BUG_ON(tm->slot != 0); |
| 1204 | eb_rewin = alloc_dummy_extent_buffer(eb->start, |
| 1205 | fs_info->tree_root->nodesize); |
| 1206 | BUG_ON(!eb_rewin); |
| 1207 | btrfs_set_header_bytenr(eb_rewin, eb->start); |
| 1208 | btrfs_set_header_backref_rev(eb_rewin, |
| 1209 | btrfs_header_backref_rev(eb)); |
| 1210 | btrfs_set_header_owner(eb_rewin, btrfs_header_owner(eb)); |
Jan Schmidt | c319310 | 2012-05-31 19:24:36 +0200 | [diff] [blame] | 1211 | btrfs_set_header_level(eb_rewin, btrfs_header_level(eb)); |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1212 | } else { |
| 1213 | eb_rewin = btrfs_clone_extent_buffer(eb); |
| 1214 | BUG_ON(!eb_rewin); |
| 1215 | } |
| 1216 | |
| 1217 | extent_buffer_get(eb_rewin); |
| 1218 | free_extent_buffer(eb); |
| 1219 | |
| 1220 | __tree_mod_log_rewind(eb_rewin, time_seq, tm); |
Jan Schmidt | 57911b8 | 2012-10-19 09:22:03 +0200 | [diff] [blame] | 1221 | WARN_ON(btrfs_header_nritems(eb_rewin) > |
| 1222 | BTRFS_NODEPTRS_PER_BLOCK(fs_info->fs_root)); |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1223 | |
| 1224 | return eb_rewin; |
| 1225 | } |
| 1226 | |
Jan Schmidt | 8ba97a1 | 2012-06-04 16:54:57 +0200 | [diff] [blame] | 1227 | /* |
| 1228 | * get_old_root() rewinds the state of @root's root node to the given @time_seq |
| 1229 | * value. If there are no changes, the current root->root_node is returned. If |
| 1230 | * anything changed in between, there's a fresh buffer allocated on which the |
| 1231 | * rewind operations are done. In any case, the returned buffer is read locked. |
| 1232 | * Returns NULL on error (with no locks held). |
| 1233 | */ |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1234 | static inline struct extent_buffer * |
| 1235 | get_old_root(struct btrfs_root *root, u64 time_seq) |
| 1236 | { |
| 1237 | struct tree_mod_elem *tm; |
| 1238 | struct extent_buffer *eb; |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1239 | struct tree_mod_root *old_root = NULL; |
Chris Mason | 4325edd | 2012-06-15 20:02:02 -0400 | [diff] [blame] | 1240 | u64 old_generation = 0; |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1241 | u64 logical; |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1242 | |
Jan Schmidt | 8ba97a1 | 2012-06-04 16:54:57 +0200 | [diff] [blame] | 1243 | eb = btrfs_read_lock_root_node(root); |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1244 | tm = __tree_mod_log_oldest_root(root->fs_info, root, time_seq); |
| 1245 | if (!tm) |
| 1246 | return root->node; |
| 1247 | |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1248 | if (tm->op == MOD_LOG_ROOT_REPLACE) { |
| 1249 | old_root = &tm->old_root; |
| 1250 | old_generation = tm->generation; |
| 1251 | logical = old_root->logical; |
| 1252 | } else { |
| 1253 | logical = root->node->start; |
| 1254 | } |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1255 | |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1256 | tm = tree_mod_log_search(root->fs_info, logical, time_seq); |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1257 | if (old_root) |
Jan Schmidt | 28da9fb | 2012-06-21 10:59:13 +0200 | [diff] [blame] | 1258 | eb = alloc_dummy_extent_buffer(logical, root->nodesize); |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1259 | else |
| 1260 | eb = btrfs_clone_extent_buffer(root->node); |
Jan Schmidt | 8ba97a1 | 2012-06-04 16:54:57 +0200 | [diff] [blame] | 1261 | btrfs_tree_read_unlock(root->node); |
| 1262 | free_extent_buffer(root->node); |
| 1263 | if (!eb) |
| 1264 | return NULL; |
| 1265 | btrfs_tree_read_lock(eb); |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1266 | if (old_root) { |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1267 | btrfs_set_header_bytenr(eb, eb->start); |
| 1268 | btrfs_set_header_backref_rev(eb, BTRFS_MIXED_BACKREF_REV); |
| 1269 | btrfs_set_header_owner(eb, root->root_key.objectid); |
Jan Schmidt | a95236d | 2012-06-05 16:41:24 +0200 | [diff] [blame] | 1270 | btrfs_set_header_level(eb, old_root->level); |
| 1271 | btrfs_set_header_generation(eb, old_generation); |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1272 | } |
Jan Schmidt | 28da9fb | 2012-06-21 10:59:13 +0200 | [diff] [blame] | 1273 | if (tm) |
| 1274 | __tree_mod_log_rewind(eb, time_seq, tm); |
| 1275 | else |
| 1276 | WARN_ON(btrfs_header_level(eb) != 0); |
Jan Schmidt | 8ba97a1 | 2012-06-04 16:54:57 +0200 | [diff] [blame] | 1277 | extent_buffer_get(eb); |
Jan Schmidt | 57911b8 | 2012-10-19 09:22:03 +0200 | [diff] [blame] | 1278 | WARN_ON(btrfs_header_nritems(eb) > BTRFS_NODEPTRS_PER_BLOCK(root)); |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 1279 | |
| 1280 | return eb; |
| 1281 | } |
| 1282 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 1283 | static inline int should_cow_block(struct btrfs_trans_handle *trans, |
| 1284 | struct btrfs_root *root, |
| 1285 | struct extent_buffer *buf) |
| 1286 | { |
Liu Bo | f1ebcc7 | 2011-11-14 20:48:06 -0500 | [diff] [blame] | 1287 | /* ensure we can see the force_cow */ |
| 1288 | smp_rmb(); |
| 1289 | |
| 1290 | /* |
| 1291 | * We do not need to cow a block if |
| 1292 | * 1) this block is not created or changed in this transaction; |
| 1293 | * 2) this block does not belong to TREE_RELOC tree; |
| 1294 | * 3) the root is not forced COW. |
| 1295 | * |
| 1296 | * What is forced COW: |
| 1297 | * when we create snapshot during commiting the transaction, |
| 1298 | * after we've finished coping src root, we must COW the shared |
| 1299 | * block to ensure the metadata consistency. |
| 1300 | */ |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 1301 | if (btrfs_header_generation(buf) == trans->transid && |
| 1302 | !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN) && |
| 1303 | !(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID && |
Liu Bo | f1ebcc7 | 2011-11-14 20:48:06 -0500 | [diff] [blame] | 1304 | btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC)) && |
| 1305 | !root->force_cow) |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 1306 | return 0; |
| 1307 | return 1; |
| 1308 | } |
| 1309 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 1310 | /* |
| 1311 | * cows a single block, see __btrfs_cow_block for the real work. |
| 1312 | * This version of it has extra checks so that a block isn't cow'd more than |
| 1313 | * once per transaction, as long as it hasn't been written yet |
| 1314 | */ |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 1315 | noinline int btrfs_cow_block(struct btrfs_trans_handle *trans, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1316 | struct btrfs_root *root, struct extent_buffer *buf, |
| 1317 | struct extent_buffer *parent, int parent_slot, |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 1318 | struct extent_buffer **cow_ret) |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 1319 | { |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1320 | u64 search_start; |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 1321 | int ret; |
Chris Mason | dc17ff8 | 2008-01-08 15:46:30 -0500 | [diff] [blame] | 1322 | |
Chris Mason | ccd467d | 2007-06-28 15:57:36 -0400 | [diff] [blame] | 1323 | if (trans->transaction != root->fs_info->running_transaction) { |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 1324 | printk(KERN_CRIT "trans %llu running %llu\n", |
| 1325 | (unsigned long long)trans->transid, |
| 1326 | (unsigned long long) |
Chris Mason | ccd467d | 2007-06-28 15:57:36 -0400 | [diff] [blame] | 1327 | root->fs_info->running_transaction->transid); |
| 1328 | WARN_ON(1); |
| 1329 | } |
| 1330 | if (trans->transid != root->fs_info->generation) { |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 1331 | printk(KERN_CRIT "trans %llu running %llu\n", |
| 1332 | (unsigned long long)trans->transid, |
| 1333 | (unsigned long long)root->fs_info->generation); |
Chris Mason | ccd467d | 2007-06-28 15:57:36 -0400 | [diff] [blame] | 1334 | WARN_ON(1); |
| 1335 | } |
Chris Mason | dc17ff8 | 2008-01-08 15:46:30 -0500 | [diff] [blame] | 1336 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 1337 | if (!should_cow_block(trans, root, buf)) { |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 1338 | *cow_ret = buf; |
| 1339 | return 0; |
| 1340 | } |
Chris Mason | c487685 | 2009-02-04 09:24:25 -0500 | [diff] [blame] | 1341 | |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 1342 | search_start = buf->start & ~((u64)(1024 * 1024 * 1024) - 1); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1343 | |
| 1344 | if (parent) |
| 1345 | btrfs_set_lock_blocking(parent); |
| 1346 | btrfs_set_lock_blocking(buf); |
| 1347 | |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 1348 | ret = __btrfs_cow_block(trans, root, buf, parent, |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 1349 | parent_slot, cow_ret, search_start, 0); |
liubo | 1abe9b8 | 2011-03-24 11:18:59 +0000 | [diff] [blame] | 1350 | |
| 1351 | trace_btrfs_cow_block(root, buf, *cow_ret); |
| 1352 | |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 1353 | return ret; |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1354 | } |
| 1355 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 1356 | /* |
| 1357 | * helper function for defrag to decide if two blocks pointed to by a |
| 1358 | * node are actually close by |
| 1359 | */ |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1360 | static int close_blocks(u64 blocknr, u64 other, u32 blocksize) |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1361 | { |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1362 | if (blocknr < other && other - (blocknr + blocksize) < 32768) |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1363 | return 1; |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1364 | if (blocknr > other && blocknr - (other + blocksize) < 32768) |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1365 | return 1; |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 1366 | return 0; |
| 1367 | } |
| 1368 | |
Chris Mason | 081e957 | 2007-11-06 10:26:24 -0500 | [diff] [blame] | 1369 | /* |
| 1370 | * compare two keys in a memcmp fashion |
| 1371 | */ |
| 1372 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) |
| 1373 | { |
| 1374 | struct btrfs_key k1; |
| 1375 | |
| 1376 | btrfs_disk_key_to_cpu(&k1, disk); |
| 1377 | |
Diego Calleja | 20736ab | 2009-07-24 11:06:52 -0400 | [diff] [blame] | 1378 | return btrfs_comp_cpu_keys(&k1, k2); |
Chris Mason | 081e957 | 2007-11-06 10:26:24 -0500 | [diff] [blame] | 1379 | } |
| 1380 | |
Josef Bacik | f3465ca | 2008-11-12 14:19:50 -0500 | [diff] [blame] | 1381 | /* |
| 1382 | * same as comp_keys only with two btrfs_key's |
| 1383 | */ |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 1384 | int btrfs_comp_cpu_keys(struct btrfs_key *k1, struct btrfs_key *k2) |
Josef Bacik | f3465ca | 2008-11-12 14:19:50 -0500 | [diff] [blame] | 1385 | { |
| 1386 | if (k1->objectid > k2->objectid) |
| 1387 | return 1; |
| 1388 | if (k1->objectid < k2->objectid) |
| 1389 | return -1; |
| 1390 | if (k1->type > k2->type) |
| 1391 | return 1; |
| 1392 | if (k1->type < k2->type) |
| 1393 | return -1; |
| 1394 | if (k1->offset > k2->offset) |
| 1395 | return 1; |
| 1396 | if (k1->offset < k2->offset) |
| 1397 | return -1; |
| 1398 | return 0; |
| 1399 | } |
Chris Mason | 081e957 | 2007-11-06 10:26:24 -0500 | [diff] [blame] | 1400 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 1401 | /* |
| 1402 | * this is used by the defrag code to go through all the |
| 1403 | * leaves pointed to by a node and reallocate them so that |
| 1404 | * disk order is close to key order |
| 1405 | */ |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1406 | int btrfs_realloc_node(struct btrfs_trans_handle *trans, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1407 | struct btrfs_root *root, struct extent_buffer *parent, |
Chris Mason | a6b6e75 | 2007-10-15 16:22:39 -0400 | [diff] [blame] | 1408 | int start_slot, int cache_only, u64 *last_ret, |
| 1409 | struct btrfs_key *progress) |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1410 | { |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1411 | struct extent_buffer *cur; |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1412 | u64 blocknr; |
Chris Mason | ca7a79a | 2008-05-12 12:59:19 -0400 | [diff] [blame] | 1413 | u64 gen; |
Chris Mason | e9d0b13 | 2007-08-10 14:06:19 -0400 | [diff] [blame] | 1414 | u64 search_start = *last_ret; |
| 1415 | u64 last_block = 0; |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1416 | u64 other; |
| 1417 | u32 parent_nritems; |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1418 | int end_slot; |
| 1419 | int i; |
| 1420 | int err = 0; |
Chris Mason | f2183bd | 2007-08-10 14:42:37 -0400 | [diff] [blame] | 1421 | int parent_level; |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1422 | int uptodate; |
| 1423 | u32 blocksize; |
Chris Mason | 081e957 | 2007-11-06 10:26:24 -0500 | [diff] [blame] | 1424 | int progress_passed = 0; |
| 1425 | struct btrfs_disk_key disk_key; |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1426 | |
Chris Mason | 5708b95 | 2007-10-25 15:43:18 -0400 | [diff] [blame] | 1427 | parent_level = btrfs_header_level(parent); |
| 1428 | if (cache_only && parent_level != 1) |
| 1429 | return 0; |
| 1430 | |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 1431 | if (trans->transaction != root->fs_info->running_transaction) |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1432 | WARN_ON(1); |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 1433 | if (trans->transid != root->fs_info->generation) |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1434 | WARN_ON(1); |
Chris Mason | 86479a0 | 2007-09-10 19:58:16 -0400 | [diff] [blame] | 1435 | |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1436 | parent_nritems = btrfs_header_nritems(parent); |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1437 | blocksize = btrfs_level_size(root, parent_level - 1); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1438 | end_slot = parent_nritems; |
| 1439 | |
| 1440 | if (parent_nritems == 1) |
| 1441 | return 0; |
| 1442 | |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1443 | btrfs_set_lock_blocking(parent); |
| 1444 | |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1445 | for (i = start_slot; i < end_slot; i++) { |
| 1446 | int close = 1; |
Chris Mason | a6b6e75 | 2007-10-15 16:22:39 -0400 | [diff] [blame] | 1447 | |
Chris Mason | 081e957 | 2007-11-06 10:26:24 -0500 | [diff] [blame] | 1448 | btrfs_node_key(parent, &disk_key, i); |
| 1449 | if (!progress_passed && comp_keys(&disk_key, progress) < 0) |
| 1450 | continue; |
| 1451 | |
| 1452 | progress_passed = 1; |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1453 | blocknr = btrfs_node_blockptr(parent, i); |
Chris Mason | ca7a79a | 2008-05-12 12:59:19 -0400 | [diff] [blame] | 1454 | gen = btrfs_node_ptr_generation(parent, i); |
Chris Mason | e9d0b13 | 2007-08-10 14:06:19 -0400 | [diff] [blame] | 1455 | if (last_block == 0) |
| 1456 | last_block = blocknr; |
Chris Mason | 5708b95 | 2007-10-25 15:43:18 -0400 | [diff] [blame] | 1457 | |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1458 | if (i > 0) { |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1459 | other = btrfs_node_blockptr(parent, i - 1); |
| 1460 | close = close_blocks(blocknr, other, blocksize); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1461 | } |
Chris Mason | 0ef3e66 | 2008-05-24 14:04:53 -0400 | [diff] [blame] | 1462 | if (!close && i < end_slot - 2) { |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1463 | other = btrfs_node_blockptr(parent, i + 1); |
| 1464 | close = close_blocks(blocknr, other, blocksize); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1465 | } |
Chris Mason | e9d0b13 | 2007-08-10 14:06:19 -0400 | [diff] [blame] | 1466 | if (close) { |
| 1467 | last_block = blocknr; |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1468 | continue; |
Chris Mason | e9d0b13 | 2007-08-10 14:06:19 -0400 | [diff] [blame] | 1469 | } |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1470 | |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1471 | cur = btrfs_find_tree_block(root, blocknr, blocksize); |
| 1472 | if (cur) |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 1473 | uptodate = btrfs_buffer_uptodate(cur, gen, 0); |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1474 | else |
| 1475 | uptodate = 0; |
Chris Mason | 5708b95 | 2007-10-25 15:43:18 -0400 | [diff] [blame] | 1476 | if (!cur || !uptodate) { |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1477 | if (cache_only) { |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1478 | free_extent_buffer(cur); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1479 | continue; |
| 1480 | } |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1481 | if (!cur) { |
| 1482 | cur = read_tree_block(root, blocknr, |
Chris Mason | ca7a79a | 2008-05-12 12:59:19 -0400 | [diff] [blame] | 1483 | blocksize, gen); |
Tsutomu Itoh | 97d9a8a | 2011-03-24 06:33:21 +0000 | [diff] [blame] | 1484 | if (!cur) |
| 1485 | return -EIO; |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1486 | } else if (!uptodate) { |
Tsutomu Itoh | 018642a | 2012-05-29 18:10:13 +0900 | [diff] [blame] | 1487 | err = btrfs_read_buffer(cur, gen); |
| 1488 | if (err) { |
| 1489 | free_extent_buffer(cur); |
| 1490 | return err; |
| 1491 | } |
Chris Mason | f2183bd | 2007-08-10 14:42:37 -0400 | [diff] [blame] | 1492 | } |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1493 | } |
Chris Mason | e9d0b13 | 2007-08-10 14:06:19 -0400 | [diff] [blame] | 1494 | if (search_start == 0) |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1495 | search_start = last_block; |
Chris Mason | e9d0b13 | 2007-08-10 14:06:19 -0400 | [diff] [blame] | 1496 | |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 1497 | btrfs_tree_lock(cur); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1498 | btrfs_set_lock_blocking(cur); |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1499 | err = __btrfs_cow_block(trans, root, cur, parent, i, |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 1500 | &cur, search_start, |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1501 | min(16 * blocksize, |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 1502 | (end_slot - i) * blocksize)); |
Yan | 252c38f | 2007-08-29 09:11:44 -0400 | [diff] [blame] | 1503 | if (err) { |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 1504 | btrfs_tree_unlock(cur); |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 1505 | free_extent_buffer(cur); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1506 | break; |
Yan | 252c38f | 2007-08-29 09:11:44 -0400 | [diff] [blame] | 1507 | } |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 1508 | search_start = cur->start; |
| 1509 | last_block = cur->start; |
Chris Mason | f2183bd | 2007-08-10 14:42:37 -0400 | [diff] [blame] | 1510 | *last_ret = search_start; |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 1511 | btrfs_tree_unlock(cur); |
| 1512 | free_extent_buffer(cur); |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 1513 | } |
| 1514 | return err; |
| 1515 | } |
| 1516 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 1517 | /* |
| 1518 | * The leaf data grows from end-to-front in the node. |
| 1519 | * this returns the address of the start of the last item, |
| 1520 | * which is the stop of the leaf data stack |
| 1521 | */ |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 1522 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1523 | struct extent_buffer *leaf) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1524 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1525 | u32 nr = btrfs_header_nritems(leaf); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1526 | if (nr == 0) |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 1527 | return BTRFS_LEAF_DATA_SIZE(root); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1528 | return btrfs_item_offset_nr(leaf, nr - 1); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1529 | } |
| 1530 | |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 1531 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 1532 | /* |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1533 | * search for key in the extent_buffer. The items start at offset p, |
| 1534 | * and they are item_size apart. There are 'max' items in p. |
| 1535 | * |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 1536 | * the slot in the array is returned via slot, and it points to |
| 1537 | * the place where you would insert key if it is not found in |
| 1538 | * the array. |
| 1539 | * |
| 1540 | * slot may point to max if the key is bigger than all of the keys |
| 1541 | */ |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 1542 | static noinline int generic_bin_search(struct extent_buffer *eb, |
| 1543 | unsigned long p, |
| 1544 | int item_size, struct btrfs_key *key, |
| 1545 | int max, int *slot) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1546 | { |
| 1547 | int low = 0; |
| 1548 | int high = max; |
| 1549 | int mid; |
| 1550 | int ret; |
Chris Mason | 479965d | 2007-10-15 16:14:27 -0400 | [diff] [blame] | 1551 | struct btrfs_disk_key *tmp = NULL; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1552 | struct btrfs_disk_key unaligned; |
| 1553 | unsigned long offset; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1554 | char *kaddr = NULL; |
| 1555 | unsigned long map_start = 0; |
| 1556 | unsigned long map_len = 0; |
Chris Mason | 479965d | 2007-10-15 16:14:27 -0400 | [diff] [blame] | 1557 | int err; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1558 | |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 1559 | while (low < high) { |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1560 | mid = (low + high) / 2; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1561 | offset = p + mid * item_size; |
| 1562 | |
Chris Mason | a659171 | 2011-07-19 12:04:14 -0400 | [diff] [blame] | 1563 | if (!kaddr || offset < map_start || |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1564 | (offset + sizeof(struct btrfs_disk_key)) > |
| 1565 | map_start + map_len) { |
Chris Mason | 934d375 | 2008-12-08 16:43:10 -0500 | [diff] [blame] | 1566 | |
| 1567 | err = map_private_extent_buffer(eb, offset, |
Chris Mason | 479965d | 2007-10-15 16:14:27 -0400 | [diff] [blame] | 1568 | sizeof(struct btrfs_disk_key), |
Chris Mason | a659171 | 2011-07-19 12:04:14 -0400 | [diff] [blame] | 1569 | &kaddr, &map_start, &map_len); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1570 | |
Chris Mason | 479965d | 2007-10-15 16:14:27 -0400 | [diff] [blame] | 1571 | if (!err) { |
| 1572 | tmp = (struct btrfs_disk_key *)(kaddr + offset - |
| 1573 | map_start); |
| 1574 | } else { |
| 1575 | read_extent_buffer(eb, &unaligned, |
| 1576 | offset, sizeof(unaligned)); |
| 1577 | tmp = &unaligned; |
| 1578 | } |
| 1579 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1580 | } else { |
| 1581 | tmp = (struct btrfs_disk_key *)(kaddr + offset - |
| 1582 | map_start); |
| 1583 | } |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1584 | ret = comp_keys(tmp, key); |
| 1585 | |
| 1586 | if (ret < 0) |
| 1587 | low = mid + 1; |
| 1588 | else if (ret > 0) |
| 1589 | high = mid; |
| 1590 | else { |
| 1591 | *slot = mid; |
| 1592 | return 0; |
| 1593 | } |
| 1594 | } |
| 1595 | *slot = low; |
| 1596 | return 1; |
| 1597 | } |
| 1598 | |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 1599 | /* |
| 1600 | * simple bin_search frontend that does the right thing for |
| 1601 | * leaves vs nodes |
| 1602 | */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1603 | static int bin_search(struct extent_buffer *eb, struct btrfs_key *key, |
| 1604 | int level, int *slot) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1605 | { |
Wang Sheng-Hui | f775738 | 2012-03-30 15:14:27 +0800 | [diff] [blame] | 1606 | if (level == 0) |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1607 | return generic_bin_search(eb, |
| 1608 | offsetof(struct btrfs_leaf, items), |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 1609 | sizeof(struct btrfs_item), |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1610 | key, btrfs_header_nritems(eb), |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 1611 | slot); |
Wang Sheng-Hui | f775738 | 2012-03-30 15:14:27 +0800 | [diff] [blame] | 1612 | else |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1613 | return generic_bin_search(eb, |
| 1614 | offsetof(struct btrfs_node, ptrs), |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 1615 | sizeof(struct btrfs_key_ptr), |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1616 | key, btrfs_header_nritems(eb), |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 1617 | slot); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 1618 | } |
| 1619 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 1620 | int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key, |
| 1621 | int level, int *slot) |
| 1622 | { |
| 1623 | return bin_search(eb, key, level, slot); |
| 1624 | } |
| 1625 | |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1626 | static void root_add_used(struct btrfs_root *root, u32 size) |
| 1627 | { |
| 1628 | spin_lock(&root->accounting_lock); |
| 1629 | btrfs_set_root_used(&root->root_item, |
| 1630 | btrfs_root_used(&root->root_item) + size); |
| 1631 | spin_unlock(&root->accounting_lock); |
| 1632 | } |
| 1633 | |
| 1634 | static void root_sub_used(struct btrfs_root *root, u32 size) |
| 1635 | { |
| 1636 | spin_lock(&root->accounting_lock); |
| 1637 | btrfs_set_root_used(&root->root_item, |
| 1638 | btrfs_root_used(&root->root_item) - size); |
| 1639 | spin_unlock(&root->accounting_lock); |
| 1640 | } |
| 1641 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 1642 | /* given a node and slot number, this reads the blocks it points to. The |
| 1643 | * extent buffer is returned with a reference taken (but unlocked). |
| 1644 | * NULL is returned on error. |
| 1645 | */ |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 1646 | static noinline struct extent_buffer *read_node_slot(struct btrfs_root *root, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1647 | struct extent_buffer *parent, int slot) |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1648 | { |
Chris Mason | ca7a79a | 2008-05-12 12:59:19 -0400 | [diff] [blame] | 1649 | int level = btrfs_header_level(parent); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1650 | if (slot < 0) |
| 1651 | return NULL; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1652 | if (slot >= btrfs_header_nritems(parent)) |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1653 | return NULL; |
Chris Mason | ca7a79a | 2008-05-12 12:59:19 -0400 | [diff] [blame] | 1654 | |
| 1655 | BUG_ON(level == 0); |
| 1656 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 1657 | return read_tree_block(root, btrfs_node_blockptr(parent, slot), |
Chris Mason | ca7a79a | 2008-05-12 12:59:19 -0400 | [diff] [blame] | 1658 | btrfs_level_size(root, level - 1), |
| 1659 | btrfs_node_ptr_generation(parent, slot)); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1660 | } |
| 1661 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 1662 | /* |
| 1663 | * node level balancing, used to make sure nodes are in proper order for |
| 1664 | * item deletion. We balance from the top down, so we have to make sure |
| 1665 | * that a deletion won't leave an node completely empty later on. |
| 1666 | */ |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 1667 | static noinline int balance_level(struct btrfs_trans_handle *trans, |
Chris Mason | 98ed517 | 2008-01-03 10:01:48 -0500 | [diff] [blame] | 1668 | struct btrfs_root *root, |
| 1669 | struct btrfs_path *path, int level) |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1670 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1671 | struct extent_buffer *right = NULL; |
| 1672 | struct extent_buffer *mid; |
| 1673 | struct extent_buffer *left = NULL; |
| 1674 | struct extent_buffer *parent = NULL; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1675 | int ret = 0; |
| 1676 | int wret; |
| 1677 | int pslot; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1678 | int orig_slot = path->slots[level]; |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1679 | u64 orig_ptr; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1680 | |
| 1681 | if (level == 0) |
| 1682 | return 0; |
| 1683 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1684 | mid = path->nodes[level]; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1685 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 1686 | WARN_ON(path->locks[level] != BTRFS_WRITE_LOCK && |
| 1687 | path->locks[level] != BTRFS_WRITE_LOCK_BLOCKING); |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 1688 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
| 1689 | |
Chris Mason | 1d4f8a0 | 2007-03-13 09:28:32 -0400 | [diff] [blame] | 1690 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1691 | |
Li Zefan | a05a9bb | 2011-09-06 16:55:34 +0800 | [diff] [blame] | 1692 | if (level < BTRFS_MAX_LEVEL - 1) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1693 | parent = path->nodes[level + 1]; |
Li Zefan | a05a9bb | 2011-09-06 16:55:34 +0800 | [diff] [blame] | 1694 | pslot = path->slots[level + 1]; |
| 1695 | } |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1696 | |
Chris Mason | 4068947 | 2007-03-17 14:29:23 -0400 | [diff] [blame] | 1697 | /* |
| 1698 | * deal with the case where there is only one pointer in the root |
| 1699 | * by promoting the node below to a root |
| 1700 | */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1701 | if (!parent) { |
| 1702 | struct extent_buffer *child; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1703 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1704 | if (btrfs_header_nritems(mid) != 1) |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1705 | return 0; |
| 1706 | |
| 1707 | /* promote the child to a root */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1708 | child = read_node_slot(root, mid, 0); |
Mark Fasheh | 305a26a | 2011-09-01 11:27:57 -0700 | [diff] [blame] | 1709 | if (!child) { |
| 1710 | ret = -EROFS; |
| 1711 | btrfs_std_error(root->fs_info, ret); |
| 1712 | goto enospc; |
| 1713 | } |
| 1714 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1715 | btrfs_tree_lock(child); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1716 | btrfs_set_lock_blocking(child); |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 1717 | ret = btrfs_cow_block(trans, root, child, mid, 0, &child); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1718 | if (ret) { |
| 1719 | btrfs_tree_unlock(child); |
| 1720 | free_extent_buffer(child); |
| 1721 | goto enospc; |
| 1722 | } |
Yan | 2f375ab | 2008-02-01 14:58:07 -0500 | [diff] [blame] | 1723 | |
Jan Schmidt | ba1bfbd | 2012-10-22 20:02:56 +0200 | [diff] [blame^] | 1724 | tree_mod_log_free_eb(root->fs_info, root->node); |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 1725 | tree_mod_log_set_root_pointer(root, child); |
Chris Mason | 240f62c | 2011-03-23 14:54:42 -0400 | [diff] [blame] | 1726 | rcu_assign_pointer(root->node, child); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1727 | |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 1728 | add_root_to_dirty_list(root); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1729 | btrfs_tree_unlock(child); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1730 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1731 | path->locks[level] = 0; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1732 | path->nodes[level] = NULL; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1733 | clean_tree_block(trans, root, mid); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1734 | btrfs_tree_unlock(mid); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1735 | /* once for the path */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1736 | free_extent_buffer(mid); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1737 | |
| 1738 | root_sub_used(root, mid->len); |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 1739 | btrfs_free_tree_block(trans, root, mid, 0, 1); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1740 | /* once for the root ptr */ |
Josef Bacik | 3083ee2 | 2012-03-09 16:01:49 -0500 | [diff] [blame] | 1741 | free_extent_buffer_stale(mid); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1742 | return 0; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1743 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1744 | if (btrfs_header_nritems(mid) > |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 1745 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1746 | return 0; |
| 1747 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1748 | left = read_node_slot(root, parent, pslot - 1); |
| 1749 | if (left) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1750 | btrfs_tree_lock(left); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1751 | btrfs_set_lock_blocking(left); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1752 | wret = btrfs_cow_block(trans, root, left, |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 1753 | parent, pslot - 1, &left); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1754 | if (wret) { |
| 1755 | ret = wret; |
| 1756 | goto enospc; |
| 1757 | } |
Chris Mason | 2cc58cf | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1758 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1759 | right = read_node_slot(root, parent, pslot + 1); |
| 1760 | if (right) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1761 | btrfs_tree_lock(right); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1762 | btrfs_set_lock_blocking(right); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1763 | wret = btrfs_cow_block(trans, root, right, |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 1764 | parent, pslot + 1, &right); |
Chris Mason | 2cc58cf | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1765 | if (wret) { |
| 1766 | ret = wret; |
| 1767 | goto enospc; |
| 1768 | } |
| 1769 | } |
| 1770 | |
| 1771 | /* first, try to make some room in the middle buffer */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1772 | if (left) { |
| 1773 | orig_slot += btrfs_header_nritems(left); |
Chris Mason | bce4eae | 2008-04-24 14:42:46 -0400 | [diff] [blame] | 1774 | wret = push_node_left(trans, root, left, mid, 1); |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1775 | if (wret < 0) |
| 1776 | ret = wret; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1777 | } |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1778 | |
| 1779 | /* |
| 1780 | * then try to empty the right most buffer into the middle |
| 1781 | */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1782 | if (right) { |
Chris Mason | 971a1f6 | 2008-04-24 10:54:32 -0400 | [diff] [blame] | 1783 | wret = push_node_left(trans, root, mid, right, 1); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1784 | if (wret < 0 && wret != -ENOSPC) |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1785 | ret = wret; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1786 | if (btrfs_header_nritems(right) == 0) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1787 | clean_tree_block(trans, root, right); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1788 | btrfs_tree_unlock(right); |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 1789 | del_ptr(trans, root, path, level + 1, pslot + 1, 1); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1790 | root_sub_used(root, right->len); |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 1791 | btrfs_free_tree_block(trans, root, right, 0, 1); |
Josef Bacik | 3083ee2 | 2012-03-09 16:01:49 -0500 | [diff] [blame] | 1792 | free_extent_buffer_stale(right); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1793 | right = NULL; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1794 | } else { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1795 | struct btrfs_disk_key right_key; |
| 1796 | btrfs_node_key(right, &right_key, 0); |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 1797 | tree_mod_log_set_node_key(root->fs_info, parent, |
| 1798 | &right_key, pslot + 1, 0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1799 | btrfs_set_node_key(parent, &right_key, pslot + 1); |
| 1800 | btrfs_mark_buffer_dirty(parent); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1801 | } |
| 1802 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1803 | if (btrfs_header_nritems(mid) == 1) { |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1804 | /* |
| 1805 | * we're not allowed to leave a node with one item in the |
| 1806 | * tree during a delete. A deletion from lower in the tree |
| 1807 | * could try to delete the only pointer in this node. |
| 1808 | * So, pull some keys from the left. |
| 1809 | * There has to be a left pointer at this point because |
| 1810 | * otherwise we would have pulled some pointers from the |
| 1811 | * right |
| 1812 | */ |
Mark Fasheh | 305a26a | 2011-09-01 11:27:57 -0700 | [diff] [blame] | 1813 | if (!left) { |
| 1814 | ret = -EROFS; |
| 1815 | btrfs_std_error(root->fs_info, ret); |
| 1816 | goto enospc; |
| 1817 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1818 | wret = balance_node_right(trans, root, mid, left); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1819 | if (wret < 0) { |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1820 | ret = wret; |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1821 | goto enospc; |
| 1822 | } |
Chris Mason | bce4eae | 2008-04-24 14:42:46 -0400 | [diff] [blame] | 1823 | if (wret == 1) { |
| 1824 | wret = push_node_left(trans, root, left, mid, 1); |
| 1825 | if (wret < 0) |
| 1826 | ret = wret; |
| 1827 | } |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1828 | BUG_ON(wret == 1); |
| 1829 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1830 | if (btrfs_header_nritems(mid) == 0) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1831 | clean_tree_block(trans, root, mid); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1832 | btrfs_tree_unlock(mid); |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 1833 | del_ptr(trans, root, path, level + 1, pslot, 1); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1834 | root_sub_used(root, mid->len); |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 1835 | btrfs_free_tree_block(trans, root, mid, 0, 1); |
Josef Bacik | 3083ee2 | 2012-03-09 16:01:49 -0500 | [diff] [blame] | 1836 | free_extent_buffer_stale(mid); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 1837 | mid = NULL; |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1838 | } else { |
| 1839 | /* update the parent key to reflect our changes */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1840 | struct btrfs_disk_key mid_key; |
| 1841 | btrfs_node_key(mid, &mid_key, 0); |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 1842 | tree_mod_log_set_node_key(root->fs_info, parent, &mid_key, |
| 1843 | pslot, 0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1844 | btrfs_set_node_key(parent, &mid_key, pslot); |
| 1845 | btrfs_mark_buffer_dirty(parent); |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1846 | } |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1847 | |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1848 | /* update the path */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1849 | if (left) { |
| 1850 | if (btrfs_header_nritems(left) > orig_slot) { |
| 1851 | extent_buffer_get(left); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1852 | /* left was locked after cow */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1853 | path->nodes[level] = left; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1854 | path->slots[level + 1] -= 1; |
| 1855 | path->slots[level] = orig_slot; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1856 | if (mid) { |
| 1857 | btrfs_tree_unlock(mid); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1858 | free_extent_buffer(mid); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1859 | } |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1860 | } else { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1861 | orig_slot -= btrfs_header_nritems(left); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1862 | path->slots[level] = orig_slot; |
| 1863 | } |
| 1864 | } |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1865 | /* double check we haven't messed things up */ |
Chris Mason | e20d96d | 2007-03-22 12:13:20 -0400 | [diff] [blame] | 1866 | if (orig_ptr != |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1867 | btrfs_node_blockptr(path->nodes[level], path->slots[level])) |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 1868 | BUG(); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1869 | enospc: |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1870 | if (right) { |
| 1871 | btrfs_tree_unlock(right); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1872 | free_extent_buffer(right); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1873 | } |
| 1874 | if (left) { |
| 1875 | if (path->nodes[level] != left) |
| 1876 | btrfs_tree_unlock(left); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1877 | free_extent_buffer(left); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1878 | } |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 1879 | return ret; |
| 1880 | } |
| 1881 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 1882 | /* Node balancing for insertion. Here we only split or push nodes around |
| 1883 | * when they are completely full. This is also done top down, so we |
| 1884 | * have to be pessimistic. |
| 1885 | */ |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 1886 | static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans, |
Chris Mason | 98ed517 | 2008-01-03 10:01:48 -0500 | [diff] [blame] | 1887 | struct btrfs_root *root, |
| 1888 | struct btrfs_path *path, int level) |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1889 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1890 | struct extent_buffer *right = NULL; |
| 1891 | struct extent_buffer *mid; |
| 1892 | struct extent_buffer *left = NULL; |
| 1893 | struct extent_buffer *parent = NULL; |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1894 | int ret = 0; |
| 1895 | int wret; |
| 1896 | int pslot; |
| 1897 | int orig_slot = path->slots[level]; |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1898 | |
| 1899 | if (level == 0) |
| 1900 | return 1; |
| 1901 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1902 | mid = path->nodes[level]; |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 1903 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1904 | |
Li Zefan | a05a9bb | 2011-09-06 16:55:34 +0800 | [diff] [blame] | 1905 | if (level < BTRFS_MAX_LEVEL - 1) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1906 | parent = path->nodes[level + 1]; |
Li Zefan | a05a9bb | 2011-09-06 16:55:34 +0800 | [diff] [blame] | 1907 | pslot = path->slots[level + 1]; |
| 1908 | } |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1909 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1910 | if (!parent) |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1911 | return 1; |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1912 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1913 | left = read_node_slot(root, parent, pslot - 1); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1914 | |
| 1915 | /* first, try to make some room in the middle buffer */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1916 | if (left) { |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1917 | u32 left_nr; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1918 | |
| 1919 | btrfs_tree_lock(left); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1920 | btrfs_set_lock_blocking(left); |
| 1921 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1922 | left_nr = btrfs_header_nritems(left); |
Chris Mason | 33ade1f | 2007-04-20 13:48:57 -0400 | [diff] [blame] | 1923 | if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
| 1924 | wret = 1; |
| 1925 | } else { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1926 | ret = btrfs_cow_block(trans, root, left, parent, |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 1927 | pslot - 1, &left); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1928 | if (ret) |
| 1929 | wret = 1; |
| 1930 | else { |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1931 | wret = push_node_left(trans, root, |
Chris Mason | 971a1f6 | 2008-04-24 10:54:32 -0400 | [diff] [blame] | 1932 | left, mid, 0); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1933 | } |
Chris Mason | 33ade1f | 2007-04-20 13:48:57 -0400 | [diff] [blame] | 1934 | } |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1935 | if (wret < 0) |
| 1936 | ret = wret; |
| 1937 | if (wret == 0) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1938 | struct btrfs_disk_key disk_key; |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1939 | orig_slot += left_nr; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1940 | btrfs_node_key(mid, &disk_key, 0); |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 1941 | tree_mod_log_set_node_key(root->fs_info, parent, |
| 1942 | &disk_key, pslot, 0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1943 | btrfs_set_node_key(parent, &disk_key, pslot); |
| 1944 | btrfs_mark_buffer_dirty(parent); |
| 1945 | if (btrfs_header_nritems(left) > orig_slot) { |
| 1946 | path->nodes[level] = left; |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1947 | path->slots[level + 1] -= 1; |
| 1948 | path->slots[level] = orig_slot; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1949 | btrfs_tree_unlock(mid); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1950 | free_extent_buffer(mid); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1951 | } else { |
| 1952 | orig_slot -= |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1953 | btrfs_header_nritems(left); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1954 | path->slots[level] = orig_slot; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1955 | btrfs_tree_unlock(left); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1956 | free_extent_buffer(left); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1957 | } |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1958 | return 0; |
| 1959 | } |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1960 | btrfs_tree_unlock(left); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1961 | free_extent_buffer(left); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1962 | } |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1963 | right = read_node_slot(root, parent, pslot + 1); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1964 | |
| 1965 | /* |
| 1966 | * then try to empty the right most buffer into the middle |
| 1967 | */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1968 | if (right) { |
Chris Mason | 33ade1f | 2007-04-20 13:48:57 -0400 | [diff] [blame] | 1969 | u32 right_nr; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1970 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 1971 | btrfs_tree_lock(right); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 1972 | btrfs_set_lock_blocking(right); |
| 1973 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1974 | right_nr = btrfs_header_nritems(right); |
Chris Mason | 33ade1f | 2007-04-20 13:48:57 -0400 | [diff] [blame] | 1975 | if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
| 1976 | wret = 1; |
| 1977 | } else { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1978 | ret = btrfs_cow_block(trans, root, right, |
| 1979 | parent, pslot + 1, |
Chris Mason | 9fa8cfe | 2009-03-13 10:24:59 -0400 | [diff] [blame] | 1980 | &right); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1981 | if (ret) |
| 1982 | wret = 1; |
| 1983 | else { |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1984 | wret = balance_node_right(trans, root, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1985 | right, mid); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 1986 | } |
Chris Mason | 33ade1f | 2007-04-20 13:48:57 -0400 | [diff] [blame] | 1987 | } |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 1988 | if (wret < 0) |
| 1989 | ret = wret; |
| 1990 | if (wret == 0) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1991 | struct btrfs_disk_key disk_key; |
| 1992 | |
| 1993 | btrfs_node_key(right, &disk_key, 0); |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 1994 | tree_mod_log_set_node_key(root->fs_info, parent, |
| 1995 | &disk_key, pslot + 1, 0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1996 | btrfs_set_node_key(parent, &disk_key, pslot + 1); |
| 1997 | btrfs_mark_buffer_dirty(parent); |
| 1998 | |
| 1999 | if (btrfs_header_nritems(mid) <= orig_slot) { |
| 2000 | path->nodes[level] = right; |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 2001 | path->slots[level + 1] += 1; |
| 2002 | path->slots[level] = orig_slot - |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2003 | btrfs_header_nritems(mid); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2004 | btrfs_tree_unlock(mid); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2005 | free_extent_buffer(mid); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 2006 | } else { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2007 | btrfs_tree_unlock(right); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2008 | free_extent_buffer(right); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 2009 | } |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 2010 | return 0; |
| 2011 | } |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2012 | btrfs_tree_unlock(right); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2013 | free_extent_buffer(right); |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 2014 | } |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 2015 | return 1; |
| 2016 | } |
| 2017 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2018 | /* |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 2019 | * readahead one full node of leaves, finding things that are close |
| 2020 | * to the block in 'slot', and triggering ra on them. |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2021 | */ |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2022 | static void reada_for_search(struct btrfs_root *root, |
| 2023 | struct btrfs_path *path, |
| 2024 | int level, int slot, u64 objectid) |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2025 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2026 | struct extent_buffer *node; |
Chris Mason | 01f4665 | 2007-12-21 16:24:26 -0500 | [diff] [blame] | 2027 | struct btrfs_disk_key disk_key; |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2028 | u32 nritems; |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2029 | u64 search; |
Chris Mason | a717531 | 2009-01-22 09:23:10 -0500 | [diff] [blame] | 2030 | u64 target; |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2031 | u64 nread = 0; |
Josef Bacik | cb25c2e | 2011-05-11 12:17:34 -0400 | [diff] [blame] | 2032 | u64 gen; |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2033 | int direction = path->reada; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2034 | struct extent_buffer *eb; |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2035 | u32 nr; |
| 2036 | u32 blocksize; |
| 2037 | u32 nscan = 0; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2038 | |
Chris Mason | a6b6e75 | 2007-10-15 16:22:39 -0400 | [diff] [blame] | 2039 | if (level != 1) |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2040 | return; |
| 2041 | |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 2042 | if (!path->nodes[level]) |
| 2043 | return; |
| 2044 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2045 | node = path->nodes[level]; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2046 | |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2047 | search = btrfs_node_blockptr(node, slot); |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2048 | blocksize = btrfs_level_size(root, level - 1); |
| 2049 | eb = btrfs_find_tree_block(root, search, blocksize); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2050 | if (eb) { |
| 2051 | free_extent_buffer(eb); |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2052 | return; |
| 2053 | } |
| 2054 | |
Chris Mason | a717531 | 2009-01-22 09:23:10 -0500 | [diff] [blame] | 2055 | target = search; |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2056 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2057 | nritems = btrfs_header_nritems(node); |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2058 | nr = slot; |
Josef Bacik | 25b8b93 | 2011-06-08 14:36:54 -0400 | [diff] [blame] | 2059 | |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 2060 | while (1) { |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2061 | if (direction < 0) { |
| 2062 | if (nr == 0) |
| 2063 | break; |
| 2064 | nr--; |
| 2065 | } else if (direction > 0) { |
| 2066 | nr++; |
| 2067 | if (nr >= nritems) |
| 2068 | break; |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2069 | } |
Chris Mason | 01f4665 | 2007-12-21 16:24:26 -0500 | [diff] [blame] | 2070 | if (path->reada < 0 && objectid) { |
| 2071 | btrfs_node_key(node, &disk_key, nr); |
| 2072 | if (btrfs_disk_key_objectid(&disk_key) != objectid) |
| 2073 | break; |
| 2074 | } |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2075 | search = btrfs_node_blockptr(node, nr); |
Chris Mason | a717531 | 2009-01-22 09:23:10 -0500 | [diff] [blame] | 2076 | if ((search <= target && target - search <= 65536) || |
| 2077 | (search > target && search - target <= 65536)) { |
Josef Bacik | cb25c2e | 2011-05-11 12:17:34 -0400 | [diff] [blame] | 2078 | gen = btrfs_node_ptr_generation(node, nr); |
Josef Bacik | cb25c2e | 2011-05-11 12:17:34 -0400 | [diff] [blame] | 2079 | readahead_tree_block(root, search, blocksize, gen); |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2080 | nread += blocksize; |
| 2081 | } |
| 2082 | nscan++; |
Chris Mason | a717531 | 2009-01-22 09:23:10 -0500 | [diff] [blame] | 2083 | if ((nread > 65536 || nscan > 32)) |
Chris Mason | 6b80053 | 2007-10-15 16:17:34 -0400 | [diff] [blame] | 2084 | break; |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2085 | } |
| 2086 | } |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2087 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 2088 | /* |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2089 | * returns -EAGAIN if it had to drop the path, or zero if everything was in |
| 2090 | * cache |
| 2091 | */ |
| 2092 | static noinline int reada_for_balance(struct btrfs_root *root, |
| 2093 | struct btrfs_path *path, int level) |
| 2094 | { |
| 2095 | int slot; |
| 2096 | int nritems; |
| 2097 | struct extent_buffer *parent; |
| 2098 | struct extent_buffer *eb; |
| 2099 | u64 gen; |
| 2100 | u64 block1 = 0; |
| 2101 | u64 block2 = 0; |
| 2102 | int ret = 0; |
| 2103 | int blocksize; |
| 2104 | |
Chris Mason | 8c594ea | 2009-04-20 15:50:10 -0400 | [diff] [blame] | 2105 | parent = path->nodes[level + 1]; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2106 | if (!parent) |
| 2107 | return 0; |
| 2108 | |
| 2109 | nritems = btrfs_header_nritems(parent); |
Chris Mason | 8c594ea | 2009-04-20 15:50:10 -0400 | [diff] [blame] | 2110 | slot = path->slots[level + 1]; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2111 | blocksize = btrfs_level_size(root, level); |
| 2112 | |
| 2113 | if (slot > 0) { |
| 2114 | block1 = btrfs_node_blockptr(parent, slot - 1); |
| 2115 | gen = btrfs_node_ptr_generation(parent, slot - 1); |
| 2116 | eb = btrfs_find_tree_block(root, block1, blocksize); |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 2117 | /* |
| 2118 | * if we get -eagain from btrfs_buffer_uptodate, we |
| 2119 | * don't want to return eagain here. That will loop |
| 2120 | * forever |
| 2121 | */ |
| 2122 | if (eb && btrfs_buffer_uptodate(eb, gen, 1) != 0) |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2123 | block1 = 0; |
| 2124 | free_extent_buffer(eb); |
| 2125 | } |
Chris Mason | 8c594ea | 2009-04-20 15:50:10 -0400 | [diff] [blame] | 2126 | if (slot + 1 < nritems) { |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2127 | block2 = btrfs_node_blockptr(parent, slot + 1); |
| 2128 | gen = btrfs_node_ptr_generation(parent, slot + 1); |
| 2129 | eb = btrfs_find_tree_block(root, block2, blocksize); |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 2130 | if (eb && btrfs_buffer_uptodate(eb, gen, 1) != 0) |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2131 | block2 = 0; |
| 2132 | free_extent_buffer(eb); |
| 2133 | } |
| 2134 | if (block1 || block2) { |
| 2135 | ret = -EAGAIN; |
Chris Mason | 8c594ea | 2009-04-20 15:50:10 -0400 | [diff] [blame] | 2136 | |
| 2137 | /* release the whole path */ |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 2138 | btrfs_release_path(path); |
Chris Mason | 8c594ea | 2009-04-20 15:50:10 -0400 | [diff] [blame] | 2139 | |
| 2140 | /* read the blocks */ |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2141 | if (block1) |
| 2142 | readahead_tree_block(root, block1, blocksize, 0); |
| 2143 | if (block2) |
| 2144 | readahead_tree_block(root, block2, blocksize, 0); |
| 2145 | |
| 2146 | if (block1) { |
| 2147 | eb = read_tree_block(root, block1, blocksize, 0); |
| 2148 | free_extent_buffer(eb); |
| 2149 | } |
Chris Mason | 8c594ea | 2009-04-20 15:50:10 -0400 | [diff] [blame] | 2150 | if (block2) { |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2151 | eb = read_tree_block(root, block2, blocksize, 0); |
| 2152 | free_extent_buffer(eb); |
| 2153 | } |
| 2154 | } |
| 2155 | return ret; |
| 2156 | } |
| 2157 | |
| 2158 | |
| 2159 | /* |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 2160 | * when we walk down the tree, it is usually safe to unlock the higher layers |
| 2161 | * in the tree. The exceptions are when our path goes through slot 0, because |
| 2162 | * operations on the tree might require changing key pointers higher up in the |
| 2163 | * tree. |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 2164 | * |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 2165 | * callers might also have set path->keep_locks, which tells this code to keep |
| 2166 | * the lock if the path points to the last slot in the block. This is part of |
| 2167 | * walking through the tree, and selecting the next slot in the higher block. |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 2168 | * |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 2169 | * lowest_unlock sets the lowest level in the tree we're allowed to unlock. so |
| 2170 | * if lowest_unlock is 1, level 0 won't be unlocked |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 2171 | */ |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 2172 | static noinline void unlock_up(struct btrfs_path *path, int level, |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 2173 | int lowest_unlock, int min_write_lock_level, |
| 2174 | int *write_lock_level) |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2175 | { |
| 2176 | int i; |
| 2177 | int skip_level = level; |
Chris Mason | 051e1b9 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2178 | int no_skips = 0; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2179 | struct extent_buffer *t; |
| 2180 | |
| 2181 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
| 2182 | if (!path->nodes[i]) |
| 2183 | break; |
| 2184 | if (!path->locks[i]) |
| 2185 | break; |
Chris Mason | 051e1b9 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2186 | if (!no_skips && path->slots[i] == 0) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2187 | skip_level = i + 1; |
| 2188 | continue; |
| 2189 | } |
Chris Mason | 051e1b9 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2190 | if (!no_skips && path->keep_locks) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2191 | u32 nritems; |
| 2192 | t = path->nodes[i]; |
| 2193 | nritems = btrfs_header_nritems(t); |
Chris Mason | 051e1b9 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2194 | if (nritems < 1 || path->slots[i] >= nritems - 1) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2195 | skip_level = i + 1; |
| 2196 | continue; |
| 2197 | } |
| 2198 | } |
Chris Mason | 051e1b9 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2199 | if (skip_level < i && i >= lowest_unlock) |
| 2200 | no_skips = 1; |
| 2201 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2202 | t = path->nodes[i]; |
| 2203 | if (i >= lowest_unlock && i > skip_level && path->locks[i]) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2204 | btrfs_tree_unlock_rw(t, path->locks[i]); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2205 | path->locks[i] = 0; |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 2206 | if (write_lock_level && |
| 2207 | i > min_write_lock_level && |
| 2208 | i <= *write_lock_level) { |
| 2209 | *write_lock_level = i - 1; |
| 2210 | } |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2211 | } |
| 2212 | } |
| 2213 | } |
| 2214 | |
Chris Mason | 3c69fae | 2007-08-07 15:52:22 -0400 | [diff] [blame] | 2215 | /* |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2216 | * This releases any locks held in the path starting at level and |
| 2217 | * going all the way up to the root. |
| 2218 | * |
| 2219 | * btrfs_search_slot will keep the lock held on higher nodes in a few |
| 2220 | * corner cases, such as COW of the block at slot zero in the node. This |
| 2221 | * ignores those rules, and it should only be called when there are no |
| 2222 | * more updates to be done higher up in the tree. |
| 2223 | */ |
| 2224 | noinline void btrfs_unlock_up_safe(struct btrfs_path *path, int level) |
| 2225 | { |
| 2226 | int i; |
| 2227 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2228 | if (path->keep_locks) |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2229 | return; |
| 2230 | |
| 2231 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
| 2232 | if (!path->nodes[i]) |
Chris Mason | 12f4dac | 2009-02-04 09:31:42 -0500 | [diff] [blame] | 2233 | continue; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2234 | if (!path->locks[i]) |
Chris Mason | 12f4dac | 2009-02-04 09:31:42 -0500 | [diff] [blame] | 2235 | continue; |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2236 | btrfs_tree_unlock_rw(path->nodes[i], path->locks[i]); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2237 | path->locks[i] = 0; |
| 2238 | } |
| 2239 | } |
| 2240 | |
| 2241 | /* |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2242 | * helper function for btrfs_search_slot. The goal is to find a block |
| 2243 | * in cache without setting the path to blocking. If we find the block |
| 2244 | * we return zero and the path is unchanged. |
| 2245 | * |
| 2246 | * If we can't find the block, we set the path blocking and do some |
| 2247 | * reada. -EAGAIN is returned and the search must be repeated. |
| 2248 | */ |
| 2249 | static int |
| 2250 | read_block_for_search(struct btrfs_trans_handle *trans, |
| 2251 | struct btrfs_root *root, struct btrfs_path *p, |
| 2252 | struct extent_buffer **eb_ret, int level, int slot, |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 2253 | struct btrfs_key *key, u64 time_seq) |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2254 | { |
| 2255 | u64 blocknr; |
| 2256 | u64 gen; |
| 2257 | u32 blocksize; |
| 2258 | struct extent_buffer *b = *eb_ret; |
| 2259 | struct extent_buffer *tmp; |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2260 | int ret; |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2261 | |
| 2262 | blocknr = btrfs_node_blockptr(b, slot); |
| 2263 | gen = btrfs_node_ptr_generation(b, slot); |
| 2264 | blocksize = btrfs_level_size(root, level - 1); |
| 2265 | |
| 2266 | tmp = btrfs_find_tree_block(root, blocknr, blocksize); |
Chris Mason | cb44921 | 2010-10-24 11:01:27 -0400 | [diff] [blame] | 2267 | if (tmp) { |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 2268 | /* first we do an atomic uptodate check */ |
| 2269 | if (btrfs_buffer_uptodate(tmp, 0, 1) > 0) { |
| 2270 | if (btrfs_buffer_uptodate(tmp, gen, 1) > 0) { |
Chris Mason | cb44921 | 2010-10-24 11:01:27 -0400 | [diff] [blame] | 2271 | /* |
| 2272 | * we found an up to date block without |
| 2273 | * sleeping, return |
| 2274 | * right away |
| 2275 | */ |
| 2276 | *eb_ret = tmp; |
| 2277 | return 0; |
| 2278 | } |
| 2279 | /* the pages were up to date, but we failed |
| 2280 | * the generation number check. Do a full |
| 2281 | * read for the generation number that is correct. |
| 2282 | * We must do this without dropping locks so |
| 2283 | * we can trust our generation number |
| 2284 | */ |
| 2285 | free_extent_buffer(tmp); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2286 | btrfs_set_path_blocking(p); |
| 2287 | |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 2288 | /* now we're allowed to do a blocking uptodate check */ |
Chris Mason | cb44921 | 2010-10-24 11:01:27 -0400 | [diff] [blame] | 2289 | tmp = read_tree_block(root, blocknr, blocksize, gen); |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 2290 | if (tmp && btrfs_buffer_uptodate(tmp, gen, 0) > 0) { |
Chris Mason | cb44921 | 2010-10-24 11:01:27 -0400 | [diff] [blame] | 2291 | *eb_ret = tmp; |
| 2292 | return 0; |
| 2293 | } |
| 2294 | free_extent_buffer(tmp); |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 2295 | btrfs_release_path(p); |
Chris Mason | cb44921 | 2010-10-24 11:01:27 -0400 | [diff] [blame] | 2296 | return -EIO; |
| 2297 | } |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2298 | } |
| 2299 | |
| 2300 | /* |
| 2301 | * reduce lock contention at high levels |
| 2302 | * of the btree by dropping locks before |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2303 | * we read. Don't release the lock on the current |
| 2304 | * level because we need to walk this node to figure |
| 2305 | * out which blocks to read. |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2306 | */ |
Chris Mason | 8c594ea | 2009-04-20 15:50:10 -0400 | [diff] [blame] | 2307 | btrfs_unlock_up_safe(p, level + 1); |
| 2308 | btrfs_set_path_blocking(p); |
| 2309 | |
Chris Mason | cb44921 | 2010-10-24 11:01:27 -0400 | [diff] [blame] | 2310 | free_extent_buffer(tmp); |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2311 | if (p->reada) |
| 2312 | reada_for_search(root, p, level, slot, key->objectid); |
| 2313 | |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 2314 | btrfs_release_path(p); |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2315 | |
| 2316 | ret = -EAGAIN; |
Yan, Zheng | 5bdd353 | 2010-05-26 11:20:30 -0400 | [diff] [blame] | 2317 | tmp = read_tree_block(root, blocknr, blocksize, 0); |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2318 | if (tmp) { |
| 2319 | /* |
| 2320 | * If the read above didn't mark this buffer up to date, |
| 2321 | * it will never end up being up to date. Set ret to EIO now |
| 2322 | * and give up so that our caller doesn't loop forever |
| 2323 | * on our EAGAINs. |
| 2324 | */ |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 2325 | if (!btrfs_buffer_uptodate(tmp, 0, 0)) |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2326 | ret = -EIO; |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2327 | free_extent_buffer(tmp); |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2328 | } |
| 2329 | return ret; |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2330 | } |
| 2331 | |
| 2332 | /* |
| 2333 | * helper function for btrfs_search_slot. This does all of the checks |
| 2334 | * for node-level blocks and does any balancing required based on |
| 2335 | * the ins_len. |
| 2336 | * |
| 2337 | * If no extra work was required, zero is returned. If we had to |
| 2338 | * drop the path, -EAGAIN is returned and btrfs_search_slot must |
| 2339 | * start over |
| 2340 | */ |
| 2341 | static int |
| 2342 | setup_nodes_for_search(struct btrfs_trans_handle *trans, |
| 2343 | struct btrfs_root *root, struct btrfs_path *p, |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2344 | struct extent_buffer *b, int level, int ins_len, |
| 2345 | int *write_lock_level) |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2346 | { |
| 2347 | int ret; |
| 2348 | if ((p->search_for_split || ins_len > 0) && btrfs_header_nritems(b) >= |
| 2349 | BTRFS_NODEPTRS_PER_BLOCK(root) - 3) { |
| 2350 | int sret; |
| 2351 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2352 | if (*write_lock_level < level + 1) { |
| 2353 | *write_lock_level = level + 1; |
| 2354 | btrfs_release_path(p); |
| 2355 | goto again; |
| 2356 | } |
| 2357 | |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2358 | sret = reada_for_balance(root, p, level); |
| 2359 | if (sret) |
| 2360 | goto again; |
| 2361 | |
| 2362 | btrfs_set_path_blocking(p); |
| 2363 | sret = split_node(trans, root, p, level); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2364 | btrfs_clear_path_blocking(p, NULL, 0); |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2365 | |
| 2366 | BUG_ON(sret > 0); |
| 2367 | if (sret) { |
| 2368 | ret = sret; |
| 2369 | goto done; |
| 2370 | } |
| 2371 | b = p->nodes[level]; |
| 2372 | } else if (ins_len < 0 && btrfs_header_nritems(b) < |
Chris Mason | cfbb930 | 2009-05-18 10:41:58 -0400 | [diff] [blame] | 2373 | BTRFS_NODEPTRS_PER_BLOCK(root) / 2) { |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2374 | int sret; |
| 2375 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2376 | if (*write_lock_level < level + 1) { |
| 2377 | *write_lock_level = level + 1; |
| 2378 | btrfs_release_path(p); |
| 2379 | goto again; |
| 2380 | } |
| 2381 | |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2382 | sret = reada_for_balance(root, p, level); |
| 2383 | if (sret) |
| 2384 | goto again; |
| 2385 | |
| 2386 | btrfs_set_path_blocking(p); |
| 2387 | sret = balance_level(trans, root, p, level); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2388 | btrfs_clear_path_blocking(p, NULL, 0); |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2389 | |
| 2390 | if (sret) { |
| 2391 | ret = sret; |
| 2392 | goto done; |
| 2393 | } |
| 2394 | b = p->nodes[level]; |
| 2395 | if (!b) { |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 2396 | btrfs_release_path(p); |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2397 | goto again; |
| 2398 | } |
| 2399 | BUG_ON(btrfs_header_nritems(b) == 1); |
| 2400 | } |
| 2401 | return 0; |
| 2402 | |
| 2403 | again: |
| 2404 | ret = -EAGAIN; |
| 2405 | done: |
| 2406 | return ret; |
| 2407 | } |
| 2408 | |
| 2409 | /* |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2410 | * look for key in the tree. path is filled in with nodes along the way |
| 2411 | * if key is found, we return zero and you can find the item in the leaf |
| 2412 | * level of the path (level 0) |
| 2413 | * |
| 2414 | * If the key isn't found, the path points to the slot where it should |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 2415 | * be inserted, and 1 is returned. If there are other errors during the |
| 2416 | * search a negative error number is returned. |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 2417 | * |
| 2418 | * if ins_len > 0, nodes and leaves will be split as we walk down the |
| 2419 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if |
| 2420 | * possible) |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2421 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame] | 2422 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
| 2423 | *root, struct btrfs_key *key, struct btrfs_path *p, int |
| 2424 | ins_len, int cow) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2425 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2426 | struct extent_buffer *b; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2427 | int slot; |
| 2428 | int ret; |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2429 | int err; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2430 | int level; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2431 | int lowest_unlock = 1; |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2432 | int root_lock; |
| 2433 | /* everything at write_lock_level or lower must be write locked */ |
| 2434 | int write_lock_level = 0; |
Chris Mason | 9f3a742 | 2007-08-07 15:52:19 -0400 | [diff] [blame] | 2435 | u8 lowest_level = 0; |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 2436 | int min_write_lock_level; |
Chris Mason | 9f3a742 | 2007-08-07 15:52:19 -0400 | [diff] [blame] | 2437 | |
Chris Mason | 6702ed4 | 2007-08-07 16:15:09 -0400 | [diff] [blame] | 2438 | lowest_level = p->lowest_level; |
Chris Mason | 323ac95 | 2008-10-01 19:05:46 -0400 | [diff] [blame] | 2439 | WARN_ON(lowest_level && ins_len > 0); |
Chris Mason | 22b0ebd | 2007-03-30 08:47:31 -0400 | [diff] [blame] | 2440 | WARN_ON(p->nodes[0] != NULL); |
Josef Bacik | 2517920 | 2008-10-29 14:49:05 -0400 | [diff] [blame] | 2441 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2442 | if (ins_len < 0) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2443 | lowest_unlock = 2; |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2444 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2445 | /* when we are removing items, we might have to go up to level |
| 2446 | * two as we update tree pointers Make sure we keep write |
| 2447 | * for those levels as well |
| 2448 | */ |
| 2449 | write_lock_level = 2; |
| 2450 | } else if (ins_len > 0) { |
| 2451 | /* |
| 2452 | * for inserting items, make sure we have a write lock on |
| 2453 | * level 1 so we can update keys |
| 2454 | */ |
| 2455 | write_lock_level = 1; |
| 2456 | } |
| 2457 | |
| 2458 | if (!cow) |
| 2459 | write_lock_level = -1; |
| 2460 | |
| 2461 | if (cow && (p->keep_locks || p->lowest_level)) |
| 2462 | write_lock_level = BTRFS_MAX_LEVEL; |
| 2463 | |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 2464 | min_write_lock_level = write_lock_level; |
| 2465 | |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 2466 | again: |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2467 | /* |
| 2468 | * we try very hard to do read locks on the root |
| 2469 | */ |
| 2470 | root_lock = BTRFS_READ_LOCK; |
| 2471 | level = 0; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2472 | if (p->search_commit_root) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2473 | /* |
| 2474 | * the commit roots are read only |
| 2475 | * so we always do read locks |
| 2476 | */ |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2477 | b = root->commit_root; |
| 2478 | extent_buffer_get(b); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2479 | level = btrfs_header_level(b); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2480 | if (!p->skip_locking) |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2481 | btrfs_tree_read_lock(b); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2482 | } else { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2483 | if (p->skip_locking) { |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2484 | b = btrfs_root_node(root); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2485 | level = btrfs_header_level(b); |
| 2486 | } else { |
| 2487 | /* we don't know the level of the root node |
| 2488 | * until we actually have it read locked |
| 2489 | */ |
| 2490 | b = btrfs_read_lock_root_node(root); |
| 2491 | level = btrfs_header_level(b); |
| 2492 | if (level <= write_lock_level) { |
| 2493 | /* whoops, must trade for write lock */ |
| 2494 | btrfs_tree_read_unlock(b); |
| 2495 | free_extent_buffer(b); |
| 2496 | b = btrfs_lock_root_node(root); |
| 2497 | root_lock = BTRFS_WRITE_LOCK; |
| 2498 | |
| 2499 | /* the level might have changed, check again */ |
| 2500 | level = btrfs_header_level(b); |
| 2501 | } |
| 2502 | } |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2503 | } |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2504 | p->nodes[level] = b; |
| 2505 | if (!p->skip_locking) |
| 2506 | p->locks[level] = root_lock; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2507 | |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 2508 | while (b) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2509 | level = btrfs_header_level(b); |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2510 | |
| 2511 | /* |
| 2512 | * setup the path here so we can release it under lock |
| 2513 | * contention with the cow code |
| 2514 | */ |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 2515 | if (cow) { |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2516 | /* |
| 2517 | * if we don't really need to cow this block |
| 2518 | * then we don't want to set the path blocking, |
| 2519 | * so we test it here |
| 2520 | */ |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2521 | if (!should_cow_block(trans, root, b)) |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2522 | goto cow_done; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 2523 | |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2524 | btrfs_set_path_blocking(p); |
| 2525 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2526 | /* |
| 2527 | * must have write locks on this node and the |
| 2528 | * parent |
| 2529 | */ |
| 2530 | if (level + 1 > write_lock_level) { |
| 2531 | write_lock_level = level + 1; |
| 2532 | btrfs_release_path(p); |
| 2533 | goto again; |
| 2534 | } |
| 2535 | |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2536 | err = btrfs_cow_block(trans, root, b, |
| 2537 | p->nodes[level + 1], |
| 2538 | p->slots[level + 1], &b); |
| 2539 | if (err) { |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2540 | ret = err; |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2541 | goto done; |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 2542 | } |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 2543 | } |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2544 | cow_done: |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 2545 | BUG_ON(!cow && ins_len); |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2546 | |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 2547 | p->nodes[level] = b; |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2548 | btrfs_clear_path_blocking(p, NULL, 0); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2549 | |
| 2550 | /* |
| 2551 | * we have a lock on b and as long as we aren't changing |
| 2552 | * the tree, there is no way to for the items in b to change. |
| 2553 | * It is safe to drop the lock on our parent before we |
| 2554 | * go through the expensive btree search on b. |
| 2555 | * |
| 2556 | * If cow is true, then we might be changing slot zero, |
| 2557 | * which may require changing the parent. So, we can't |
| 2558 | * drop the lock until after we know which slot we're |
| 2559 | * operating on. |
| 2560 | */ |
| 2561 | if (!cow) |
| 2562 | btrfs_unlock_up_safe(p, level + 1); |
| 2563 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2564 | ret = bin_search(b, key, level, &slot); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2565 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2566 | if (level != 0) { |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2567 | int dec = 0; |
| 2568 | if (ret && slot > 0) { |
| 2569 | dec = 1; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2570 | slot -= 1; |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2571 | } |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2572 | p->slots[level] = slot; |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2573 | err = setup_nodes_for_search(trans, root, p, b, level, |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2574 | ins_len, &write_lock_level); |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2575 | if (err == -EAGAIN) |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2576 | goto again; |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2577 | if (err) { |
| 2578 | ret = err; |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2579 | goto done; |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2580 | } |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2581 | b = p->nodes[level]; |
| 2582 | slot = p->slots[level]; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2583 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2584 | /* |
| 2585 | * slot 0 is special, if we change the key |
| 2586 | * we have to update the parent pointer |
| 2587 | * which means we must have a write lock |
| 2588 | * on the parent |
| 2589 | */ |
| 2590 | if (slot == 0 && cow && |
| 2591 | write_lock_level < level + 1) { |
| 2592 | write_lock_level = level + 1; |
| 2593 | btrfs_release_path(p); |
| 2594 | goto again; |
| 2595 | } |
| 2596 | |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 2597 | unlock_up(p, level, lowest_unlock, |
| 2598 | min_write_lock_level, &write_lock_level); |
Chris Mason | f9efa9c | 2008-06-25 16:14:04 -0400 | [diff] [blame] | 2599 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2600 | if (level == lowest_level) { |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2601 | if (dec) |
| 2602 | p->slots[level]++; |
Zheng Yan | 5b21f2e | 2008-09-26 10:05:38 -0400 | [diff] [blame] | 2603 | goto done; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 2604 | } |
Chris Mason | ca7a79a | 2008-05-12 12:59:19 -0400 | [diff] [blame] | 2605 | |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2606 | err = read_block_for_search(trans, root, p, |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 2607 | &b, level, slot, key, 0); |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2608 | if (err == -EAGAIN) |
Chris Mason | c8c4286 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 2609 | goto again; |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2610 | if (err) { |
| 2611 | ret = err; |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2612 | goto done; |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2613 | } |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2614 | |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2615 | if (!p->skip_locking) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2616 | level = btrfs_header_level(b); |
| 2617 | if (level <= write_lock_level) { |
| 2618 | err = btrfs_try_tree_write_lock(b); |
| 2619 | if (!err) { |
| 2620 | btrfs_set_path_blocking(p); |
| 2621 | btrfs_tree_lock(b); |
| 2622 | btrfs_clear_path_blocking(p, b, |
| 2623 | BTRFS_WRITE_LOCK); |
| 2624 | } |
| 2625 | p->locks[level] = BTRFS_WRITE_LOCK; |
| 2626 | } else { |
| 2627 | err = btrfs_try_tree_read_lock(b); |
| 2628 | if (!err) { |
| 2629 | btrfs_set_path_blocking(p); |
| 2630 | btrfs_tree_read_lock(b); |
| 2631 | btrfs_clear_path_blocking(p, b, |
| 2632 | BTRFS_READ_LOCK); |
| 2633 | } |
| 2634 | p->locks[level] = BTRFS_READ_LOCK; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2635 | } |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2636 | p->nodes[level] = b; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2637 | } |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2638 | } else { |
| 2639 | p->slots[level] = slot; |
Yan Zheng | 87b29b2 | 2008-12-17 10:21:48 -0500 | [diff] [blame] | 2640 | if (ins_len > 0 && |
| 2641 | btrfs_leaf_free_space(root, b) < ins_len) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2642 | if (write_lock_level < 1) { |
| 2643 | write_lock_level = 1; |
| 2644 | btrfs_release_path(p); |
| 2645 | goto again; |
| 2646 | } |
| 2647 | |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2648 | btrfs_set_path_blocking(p); |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2649 | err = split_leaf(trans, root, key, |
| 2650 | p, ins_len, ret == 0); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 2651 | btrfs_clear_path_blocking(p, NULL, 0); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2652 | |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 2653 | BUG_ON(err > 0); |
| 2654 | if (err) { |
| 2655 | ret = err; |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2656 | goto done; |
| 2657 | } |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 2658 | } |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 2659 | if (!p->search_for_split) |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 2660 | unlock_up(p, level, lowest_unlock, |
| 2661 | min_write_lock_level, &write_lock_level); |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2662 | goto done; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2663 | } |
| 2664 | } |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2665 | ret = 1; |
| 2666 | done: |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 2667 | /* |
| 2668 | * we don't really know what they plan on doing with the path |
| 2669 | * from here on, so for now just mark it as blocking |
| 2670 | */ |
Chris Mason | b947343 | 2009-03-13 11:00:37 -0400 | [diff] [blame] | 2671 | if (!p->leave_spinning) |
| 2672 | btrfs_set_path_blocking(p); |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 2673 | if (ret < 0) |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 2674 | btrfs_release_path(p); |
Chris Mason | 65b51a0 | 2008-08-01 15:11:20 -0400 | [diff] [blame] | 2675 | return ret; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2676 | } |
| 2677 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2678 | /* |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 2679 | * Like btrfs_search_slot, this looks for a key in the given tree. It uses the |
| 2680 | * current state of the tree together with the operations recorded in the tree |
| 2681 | * modification log to search for the key in a previous version of this tree, as |
| 2682 | * denoted by the time_seq parameter. |
| 2683 | * |
| 2684 | * Naturally, there is no support for insert, delete or cow operations. |
| 2685 | * |
| 2686 | * The resulting path and return value will be set up as if we called |
| 2687 | * btrfs_search_slot at that point in time with ins_len and cow both set to 0. |
| 2688 | */ |
| 2689 | int btrfs_search_old_slot(struct btrfs_root *root, struct btrfs_key *key, |
| 2690 | struct btrfs_path *p, u64 time_seq) |
| 2691 | { |
| 2692 | struct extent_buffer *b; |
| 2693 | int slot; |
| 2694 | int ret; |
| 2695 | int err; |
| 2696 | int level; |
| 2697 | int lowest_unlock = 1; |
| 2698 | u8 lowest_level = 0; |
| 2699 | |
| 2700 | lowest_level = p->lowest_level; |
| 2701 | WARN_ON(p->nodes[0] != NULL); |
| 2702 | |
| 2703 | if (p->search_commit_root) { |
| 2704 | BUG_ON(time_seq); |
| 2705 | return btrfs_search_slot(NULL, root, key, p, 0, 0); |
| 2706 | } |
| 2707 | |
| 2708 | again: |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 2709 | b = get_old_root(root, time_seq); |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 2710 | level = btrfs_header_level(b); |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 2711 | p->locks[level] = BTRFS_READ_LOCK; |
| 2712 | |
| 2713 | while (b) { |
| 2714 | level = btrfs_header_level(b); |
| 2715 | p->nodes[level] = b; |
| 2716 | btrfs_clear_path_blocking(p, NULL, 0); |
| 2717 | |
| 2718 | /* |
| 2719 | * we have a lock on b and as long as we aren't changing |
| 2720 | * the tree, there is no way to for the items in b to change. |
| 2721 | * It is safe to drop the lock on our parent before we |
| 2722 | * go through the expensive btree search on b. |
| 2723 | */ |
| 2724 | btrfs_unlock_up_safe(p, level + 1); |
| 2725 | |
| 2726 | ret = bin_search(b, key, level, &slot); |
| 2727 | |
| 2728 | if (level != 0) { |
| 2729 | int dec = 0; |
| 2730 | if (ret && slot > 0) { |
| 2731 | dec = 1; |
| 2732 | slot -= 1; |
| 2733 | } |
| 2734 | p->slots[level] = slot; |
| 2735 | unlock_up(p, level, lowest_unlock, 0, NULL); |
| 2736 | |
| 2737 | if (level == lowest_level) { |
| 2738 | if (dec) |
| 2739 | p->slots[level]++; |
| 2740 | goto done; |
| 2741 | } |
| 2742 | |
| 2743 | err = read_block_for_search(NULL, root, p, &b, level, |
| 2744 | slot, key, time_seq); |
| 2745 | if (err == -EAGAIN) |
| 2746 | goto again; |
| 2747 | if (err) { |
| 2748 | ret = err; |
| 2749 | goto done; |
| 2750 | } |
| 2751 | |
| 2752 | level = btrfs_header_level(b); |
| 2753 | err = btrfs_try_tree_read_lock(b); |
| 2754 | if (!err) { |
| 2755 | btrfs_set_path_blocking(p); |
| 2756 | btrfs_tree_read_lock(b); |
| 2757 | btrfs_clear_path_blocking(p, b, |
| 2758 | BTRFS_READ_LOCK); |
| 2759 | } |
| 2760 | p->locks[level] = BTRFS_READ_LOCK; |
| 2761 | p->nodes[level] = b; |
| 2762 | b = tree_mod_log_rewind(root->fs_info, b, time_seq); |
| 2763 | if (b != p->nodes[level]) { |
| 2764 | btrfs_tree_unlock_rw(p->nodes[level], |
| 2765 | p->locks[level]); |
| 2766 | p->locks[level] = 0; |
| 2767 | p->nodes[level] = b; |
| 2768 | } |
| 2769 | } else { |
| 2770 | p->slots[level] = slot; |
| 2771 | unlock_up(p, level, lowest_unlock, 0, NULL); |
| 2772 | goto done; |
| 2773 | } |
| 2774 | } |
| 2775 | ret = 1; |
| 2776 | done: |
| 2777 | if (!p->leave_spinning) |
| 2778 | btrfs_set_path_blocking(p); |
| 2779 | if (ret < 0) |
| 2780 | btrfs_release_path(p); |
| 2781 | |
| 2782 | return ret; |
| 2783 | } |
| 2784 | |
| 2785 | /* |
Arne Jansen | 2f38b3e | 2011-09-13 11:18:10 +0200 | [diff] [blame] | 2786 | * helper to use instead of search slot if no exact match is needed but |
| 2787 | * instead the next or previous item should be returned. |
| 2788 | * When find_higher is true, the next higher item is returned, the next lower |
| 2789 | * otherwise. |
| 2790 | * When return_any and find_higher are both true, and no higher item is found, |
| 2791 | * return the next lower instead. |
| 2792 | * When return_any is true and find_higher is false, and no lower item is found, |
| 2793 | * return the next higher instead. |
| 2794 | * It returns 0 if any item is found, 1 if none is found (tree empty), and |
| 2795 | * < 0 on error |
| 2796 | */ |
| 2797 | int btrfs_search_slot_for_read(struct btrfs_root *root, |
| 2798 | struct btrfs_key *key, struct btrfs_path *p, |
| 2799 | int find_higher, int return_any) |
| 2800 | { |
| 2801 | int ret; |
| 2802 | struct extent_buffer *leaf; |
| 2803 | |
| 2804 | again: |
| 2805 | ret = btrfs_search_slot(NULL, root, key, p, 0, 0); |
| 2806 | if (ret <= 0) |
| 2807 | return ret; |
| 2808 | /* |
| 2809 | * a return value of 1 means the path is at the position where the |
| 2810 | * item should be inserted. Normally this is the next bigger item, |
| 2811 | * but in case the previous item is the last in a leaf, path points |
| 2812 | * to the first free slot in the previous leaf, i.e. at an invalid |
| 2813 | * item. |
| 2814 | */ |
| 2815 | leaf = p->nodes[0]; |
| 2816 | |
| 2817 | if (find_higher) { |
| 2818 | if (p->slots[0] >= btrfs_header_nritems(leaf)) { |
| 2819 | ret = btrfs_next_leaf(root, p); |
| 2820 | if (ret <= 0) |
| 2821 | return ret; |
| 2822 | if (!return_any) |
| 2823 | return 1; |
| 2824 | /* |
| 2825 | * no higher item found, return the next |
| 2826 | * lower instead |
| 2827 | */ |
| 2828 | return_any = 0; |
| 2829 | find_higher = 0; |
| 2830 | btrfs_release_path(p); |
| 2831 | goto again; |
| 2832 | } |
| 2833 | } else { |
Arne Jansen | e679376 | 2011-09-13 11:18:10 +0200 | [diff] [blame] | 2834 | if (p->slots[0] == 0) { |
| 2835 | ret = btrfs_prev_leaf(root, p); |
| 2836 | if (ret < 0) |
| 2837 | return ret; |
| 2838 | if (!ret) { |
| 2839 | p->slots[0] = btrfs_header_nritems(leaf) - 1; |
| 2840 | return 0; |
Arne Jansen | 2f38b3e | 2011-09-13 11:18:10 +0200 | [diff] [blame] | 2841 | } |
Arne Jansen | e679376 | 2011-09-13 11:18:10 +0200 | [diff] [blame] | 2842 | if (!return_any) |
| 2843 | return 1; |
| 2844 | /* |
| 2845 | * no lower item found, return the next |
| 2846 | * higher instead |
| 2847 | */ |
| 2848 | return_any = 0; |
| 2849 | find_higher = 1; |
| 2850 | btrfs_release_path(p); |
| 2851 | goto again; |
| 2852 | } else { |
Arne Jansen | 2f38b3e | 2011-09-13 11:18:10 +0200 | [diff] [blame] | 2853 | --p->slots[0]; |
| 2854 | } |
| 2855 | } |
| 2856 | return 0; |
| 2857 | } |
| 2858 | |
| 2859 | /* |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2860 | * adjust the pointers going up the tree, starting at level |
| 2861 | * making sure the right key of each node is points to 'key'. |
| 2862 | * This is used after shifting pointers to the left, so it stops |
| 2863 | * fixing up pointers when a given leaf/node is not in slot 0 of the |
| 2864 | * higher levels |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 2865 | * |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2866 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 2867 | static void fixup_low_keys(struct btrfs_trans_handle *trans, |
| 2868 | struct btrfs_root *root, struct btrfs_path *path, |
| 2869 | struct btrfs_disk_key *key, int level) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2870 | { |
| 2871 | int i; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2872 | struct extent_buffer *t; |
| 2873 | |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 2874 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2875 | int tslot = path->slots[i]; |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 2876 | if (!path->nodes[i]) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2877 | break; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2878 | t = path->nodes[i]; |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 2879 | tree_mod_log_set_node_key(root->fs_info, t, key, tslot, 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2880 | btrfs_set_node_key(t, key, tslot); |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 2881 | btrfs_mark_buffer_dirty(path->nodes[i]); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2882 | if (tslot != 0) |
| 2883 | break; |
| 2884 | } |
| 2885 | } |
| 2886 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2887 | /* |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 2888 | * update item key. |
| 2889 | * |
| 2890 | * This function isn't completely safe. It's the caller's responsibility |
| 2891 | * that the new key won't break the order |
| 2892 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 2893 | void btrfs_set_item_key_safe(struct btrfs_trans_handle *trans, |
| 2894 | struct btrfs_root *root, struct btrfs_path *path, |
| 2895 | struct btrfs_key *new_key) |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 2896 | { |
| 2897 | struct btrfs_disk_key disk_key; |
| 2898 | struct extent_buffer *eb; |
| 2899 | int slot; |
| 2900 | |
| 2901 | eb = path->nodes[0]; |
| 2902 | slot = path->slots[0]; |
| 2903 | if (slot > 0) { |
| 2904 | btrfs_item_key(eb, &disk_key, slot - 1); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 2905 | BUG_ON(comp_keys(&disk_key, new_key) >= 0); |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 2906 | } |
| 2907 | if (slot < btrfs_header_nritems(eb) - 1) { |
| 2908 | btrfs_item_key(eb, &disk_key, slot + 1); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 2909 | BUG_ON(comp_keys(&disk_key, new_key) <= 0); |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 2910 | } |
| 2911 | |
| 2912 | btrfs_cpu_key_to_disk(&disk_key, new_key); |
| 2913 | btrfs_set_item_key(eb, &disk_key, slot); |
| 2914 | btrfs_mark_buffer_dirty(eb); |
| 2915 | if (slot == 0) |
| 2916 | fixup_low_keys(trans, root, path, &disk_key, 1); |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 2917 | } |
| 2918 | |
| 2919 | /* |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2920 | * try to push data from one node into the next node left in the |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 2921 | * tree. |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 2922 | * |
| 2923 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible |
| 2924 | * error, and > 0 if there was no room in the left hand block. |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 2925 | */ |
Chris Mason | 98ed517 | 2008-01-03 10:01:48 -0500 | [diff] [blame] | 2926 | static int push_node_left(struct btrfs_trans_handle *trans, |
| 2927 | struct btrfs_root *root, struct extent_buffer *dst, |
Chris Mason | 971a1f6 | 2008-04-24 10:54:32 -0400 | [diff] [blame] | 2928 | struct extent_buffer *src, int empty) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2929 | { |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2930 | int push_items = 0; |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 2931 | int src_nritems; |
| 2932 | int dst_nritems; |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 2933 | int ret = 0; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2934 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2935 | src_nritems = btrfs_header_nritems(src); |
| 2936 | dst_nritems = btrfs_header_nritems(dst); |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 2937 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 2938 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
| 2939 | WARN_ON(btrfs_header_generation(dst) != trans->transid); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 2940 | |
Chris Mason | bce4eae | 2008-04-24 14:42:46 -0400 | [diff] [blame] | 2941 | if (!empty && src_nritems <= 8) |
Chris Mason | 971a1f6 | 2008-04-24 10:54:32 -0400 | [diff] [blame] | 2942 | return 1; |
| 2943 | |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 2944 | if (push_items <= 0) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2945 | return 1; |
| 2946 | |
Chris Mason | bce4eae | 2008-04-24 14:42:46 -0400 | [diff] [blame] | 2947 | if (empty) { |
Chris Mason | 971a1f6 | 2008-04-24 10:54:32 -0400 | [diff] [blame] | 2948 | push_items = min(src_nritems, push_items); |
Chris Mason | bce4eae | 2008-04-24 14:42:46 -0400 | [diff] [blame] | 2949 | if (push_items < src_nritems) { |
| 2950 | /* leave at least 8 pointers in the node if |
| 2951 | * we aren't going to empty it |
| 2952 | */ |
| 2953 | if (src_nritems - push_items < 8) { |
| 2954 | if (push_items <= 8) |
| 2955 | return 1; |
| 2956 | push_items -= 8; |
| 2957 | } |
| 2958 | } |
| 2959 | } else |
| 2960 | push_items = min(src_nritems - 8, push_items); |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 2961 | |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 2962 | tree_mod_log_eb_copy(root->fs_info, dst, src, dst_nritems, 0, |
| 2963 | push_items); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2964 | copy_extent_buffer(dst, src, |
| 2965 | btrfs_node_key_ptr_offset(dst_nritems), |
| 2966 | btrfs_node_key_ptr_offset(0), |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 2967 | push_items * sizeof(struct btrfs_key_ptr)); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2968 | |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 2969 | if (push_items < src_nritems) { |
Jan Schmidt | 57911b8 | 2012-10-19 09:22:03 +0200 | [diff] [blame] | 2970 | /* |
| 2971 | * don't call tree_mod_log_eb_move here, key removal was already |
| 2972 | * fully logged by tree_mod_log_eb_copy above. |
| 2973 | */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2974 | memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0), |
| 2975 | btrfs_node_key_ptr_offset(push_items), |
| 2976 | (src_nritems - push_items) * |
| 2977 | sizeof(struct btrfs_key_ptr)); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 2978 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2979 | btrfs_set_header_nritems(src, src_nritems - push_items); |
| 2980 | btrfs_set_header_nritems(dst, dst_nritems + push_items); |
| 2981 | btrfs_mark_buffer_dirty(src); |
| 2982 | btrfs_mark_buffer_dirty(dst); |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 2983 | |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 2984 | return ret; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 2985 | } |
| 2986 | |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 2987 | /* |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 2988 | * try to push data from one node into the next node right in the |
| 2989 | * tree. |
| 2990 | * |
| 2991 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible |
| 2992 | * error, and > 0 if there was no room in the right hand block. |
| 2993 | * |
| 2994 | * this will only push up to 1/2 the contents of the left node over |
| 2995 | */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2996 | static int balance_node_right(struct btrfs_trans_handle *trans, |
| 2997 | struct btrfs_root *root, |
| 2998 | struct extent_buffer *dst, |
| 2999 | struct extent_buffer *src) |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3000 | { |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3001 | int push_items = 0; |
| 3002 | int max_push; |
| 3003 | int src_nritems; |
| 3004 | int dst_nritems; |
| 3005 | int ret = 0; |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3006 | |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 3007 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
| 3008 | WARN_ON(btrfs_header_generation(dst) != trans->transid); |
| 3009 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3010 | src_nritems = btrfs_header_nritems(src); |
| 3011 | dst_nritems = btrfs_header_nritems(dst); |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 3012 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3013 | if (push_items <= 0) |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3014 | return 1; |
Chris Mason | bce4eae | 2008-04-24 14:42:46 -0400 | [diff] [blame] | 3015 | |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3016 | if (src_nritems < 4) |
Chris Mason | bce4eae | 2008-04-24 14:42:46 -0400 | [diff] [blame] | 3017 | return 1; |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3018 | |
| 3019 | max_push = src_nritems / 2 + 1; |
| 3020 | /* don't try to empty the node */ |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3021 | if (max_push >= src_nritems) |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3022 | return 1; |
Yan | 252c38f | 2007-08-29 09:11:44 -0400 | [diff] [blame] | 3023 | |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3024 | if (max_push < push_items) |
| 3025 | push_items = max_push; |
| 3026 | |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 3027 | tree_mod_log_eb_move(root->fs_info, dst, push_items, 0, dst_nritems); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3028 | memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items), |
| 3029 | btrfs_node_key_ptr_offset(0), |
| 3030 | (dst_nritems) * |
| 3031 | sizeof(struct btrfs_key_ptr)); |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 3032 | |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 3033 | tree_mod_log_eb_copy(root->fs_info, dst, src, 0, |
| 3034 | src_nritems - push_items, push_items); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3035 | copy_extent_buffer(dst, src, |
| 3036 | btrfs_node_key_ptr_offset(0), |
| 3037 | btrfs_node_key_ptr_offset(src_nritems - push_items), |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3038 | push_items * sizeof(struct btrfs_key_ptr)); |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3039 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3040 | btrfs_set_header_nritems(src, src_nritems - push_items); |
| 3041 | btrfs_set_header_nritems(dst, dst_nritems + push_items); |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3042 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3043 | btrfs_mark_buffer_dirty(src); |
| 3044 | btrfs_mark_buffer_dirty(dst); |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3045 | |
Chris Mason | 79f95c8 | 2007-03-01 15:16:26 -0500 | [diff] [blame] | 3046 | return ret; |
| 3047 | } |
| 3048 | |
| 3049 | /* |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 3050 | * helper function to insert a new root level in the tree. |
| 3051 | * A new node is allocated, and a single item is inserted to |
| 3052 | * point to the existing root |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 3053 | * |
| 3054 | * returns zero on success or < 0 on failure. |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 3055 | */ |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3056 | static noinline int insert_new_root(struct btrfs_trans_handle *trans, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3057 | struct btrfs_root *root, |
| 3058 | struct btrfs_path *path, int level) |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3059 | { |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 3060 | u64 lower_gen; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3061 | struct extent_buffer *lower; |
| 3062 | struct extent_buffer *c; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3063 | struct extent_buffer *old; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3064 | struct btrfs_disk_key lower_key; |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3065 | |
| 3066 | BUG_ON(path->nodes[level]); |
| 3067 | BUG_ON(path->nodes[level-1] != root->node); |
| 3068 | |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 3069 | lower = path->nodes[level-1]; |
| 3070 | if (level == 1) |
| 3071 | btrfs_item_key(lower, &lower_key, 0); |
| 3072 | else |
| 3073 | btrfs_node_key(lower, &lower_key, 0); |
| 3074 | |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3075 | c = btrfs_alloc_free_block(trans, root, root->nodesize, 0, |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3076 | root->root_key.objectid, &lower_key, |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 3077 | level, root->node->start, 0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3078 | if (IS_ERR(c)) |
| 3079 | return PTR_ERR(c); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3080 | |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 3081 | root_add_used(root, root->nodesize); |
| 3082 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3083 | memset_extent_buffer(c, 0, 0, sizeof(struct btrfs_header)); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3084 | btrfs_set_header_nritems(c, 1); |
| 3085 | btrfs_set_header_level(c, level); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3086 | btrfs_set_header_bytenr(c, c->start); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3087 | btrfs_set_header_generation(c, trans->transid); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3088 | btrfs_set_header_backref_rev(c, BTRFS_MIXED_BACKREF_REV); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3089 | btrfs_set_header_owner(c, root->root_key.objectid); |
Chris Mason | d571976 | 2007-03-23 10:01:08 -0400 | [diff] [blame] | 3090 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3091 | write_extent_buffer(c, root->fs_info->fsid, |
| 3092 | (unsigned long)btrfs_header_fsid(c), |
| 3093 | BTRFS_FSID_SIZE); |
Chris Mason | e17cade | 2008-04-15 15:41:47 -0400 | [diff] [blame] | 3094 | |
| 3095 | write_extent_buffer(c, root->fs_info->chunk_tree_uuid, |
| 3096 | (unsigned long)btrfs_header_chunk_tree_uuid(c), |
| 3097 | BTRFS_UUID_SIZE); |
| 3098 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3099 | btrfs_set_node_key(c, &lower_key, 0); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3100 | btrfs_set_node_blockptr(c, 0, lower->start); |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 3101 | lower_gen = btrfs_header_generation(lower); |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3102 | WARN_ON(lower_gen != trans->transid); |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 3103 | |
| 3104 | btrfs_set_node_ptr_generation(c, 0, lower_gen); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3105 | |
| 3106 | btrfs_mark_buffer_dirty(c); |
Chris Mason | d571976 | 2007-03-23 10:01:08 -0400 | [diff] [blame] | 3107 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3108 | old = root->node; |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 3109 | tree_mod_log_set_root_pointer(root, c); |
Chris Mason | 240f62c | 2011-03-23 14:54:42 -0400 | [diff] [blame] | 3110 | rcu_assign_pointer(root->node, c); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3111 | |
| 3112 | /* the super has an extra ref to root->node */ |
| 3113 | free_extent_buffer(old); |
| 3114 | |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 3115 | add_root_to_dirty_list(root); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3116 | extent_buffer_get(c); |
| 3117 | path->nodes[level] = c; |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 3118 | path->locks[level] = BTRFS_WRITE_LOCK; |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3119 | path->slots[level] = 0; |
| 3120 | return 0; |
| 3121 | } |
| 3122 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3123 | /* |
| 3124 | * worker function to insert a single pointer in a node. |
| 3125 | * the node should have enough room for the pointer already |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 3126 | * |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3127 | * slot and level indicate where you want the key to go, and |
| 3128 | * blocknr is the block the key points to. |
| 3129 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 3130 | static void insert_ptr(struct btrfs_trans_handle *trans, |
| 3131 | struct btrfs_root *root, struct btrfs_path *path, |
| 3132 | struct btrfs_disk_key *key, u64 bytenr, |
Jan Schmidt | c3e0696 | 2012-06-21 11:01:06 +0200 | [diff] [blame] | 3133 | int slot, int level) |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3134 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3135 | struct extent_buffer *lower; |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3136 | int nritems; |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 3137 | int ret; |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3138 | |
| 3139 | BUG_ON(!path->nodes[level]); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 3140 | btrfs_assert_tree_locked(path->nodes[level]); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3141 | lower = path->nodes[level]; |
| 3142 | nritems = btrfs_header_nritems(lower); |
Stoyan Gaydarov | c293498 | 2009-04-02 17:05:11 -0400 | [diff] [blame] | 3143 | BUG_ON(slot > nritems); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 3144 | BUG_ON(nritems == BTRFS_NODEPTRS_PER_BLOCK(root)); |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3145 | if (slot != nritems) { |
Jan Schmidt | c3e0696 | 2012-06-21 11:01:06 +0200 | [diff] [blame] | 3146 | if (level) |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 3147 | tree_mod_log_eb_move(root->fs_info, lower, slot + 1, |
| 3148 | slot, nritems - slot); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3149 | memmove_extent_buffer(lower, |
| 3150 | btrfs_node_key_ptr_offset(slot + 1), |
| 3151 | btrfs_node_key_ptr_offset(slot), |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 3152 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3153 | } |
Jan Schmidt | c3e0696 | 2012-06-21 11:01:06 +0200 | [diff] [blame] | 3154 | if (level) { |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 3155 | ret = tree_mod_log_insert_key(root->fs_info, lower, slot, |
| 3156 | MOD_LOG_KEY_ADD); |
| 3157 | BUG_ON(ret < 0); |
| 3158 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3159 | btrfs_set_node_key(lower, key, slot); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3160 | btrfs_set_node_blockptr(lower, slot, bytenr); |
Chris Mason | 74493f7 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 3161 | WARN_ON(trans->transid == 0); |
| 3162 | btrfs_set_node_ptr_generation(lower, slot, trans->transid); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3163 | btrfs_set_header_nritems(lower, nritems + 1); |
| 3164 | btrfs_mark_buffer_dirty(lower); |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3165 | } |
| 3166 | |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 3167 | /* |
| 3168 | * split the node at the specified level in path in two. |
| 3169 | * The path is corrected to point to the appropriate node after the split |
| 3170 | * |
| 3171 | * Before splitting this tries to make some room in the node by pushing |
| 3172 | * left and right, if either one works, it returns right away. |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 3173 | * |
| 3174 | * returns 0 on success and < 0 on failure |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 3175 | */ |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 3176 | static noinline int split_node(struct btrfs_trans_handle *trans, |
| 3177 | struct btrfs_root *root, |
| 3178 | struct btrfs_path *path, int level) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3179 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3180 | struct extent_buffer *c; |
| 3181 | struct extent_buffer *split; |
| 3182 | struct btrfs_disk_key disk_key; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3183 | int mid; |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3184 | int ret; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 3185 | u32 c_nritems; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3186 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3187 | c = path->nodes[level]; |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 3188 | WARN_ON(btrfs_header_generation(c) != trans->transid); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3189 | if (c == root->node) { |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3190 | /* trying to split the root, lets make a new one */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame] | 3191 | ret = insert_new_root(trans, root, path, level + 1); |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3192 | if (ret) |
| 3193 | return ret; |
Chris Mason | b361242 | 2009-05-13 19:12:15 -0400 | [diff] [blame] | 3194 | } else { |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 3195 | ret = push_nodes_for_insert(trans, root, path, level); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3196 | c = path->nodes[level]; |
| 3197 | if (!ret && btrfs_header_nritems(c) < |
Chris Mason | c448acf | 2008-04-24 09:34:34 -0400 | [diff] [blame] | 3198 | BTRFS_NODEPTRS_PER_BLOCK(root) - 3) |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 3199 | return 0; |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 3200 | if (ret < 0) |
| 3201 | return ret; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3202 | } |
Chris Mason | e66f709 | 2007-04-20 13:16:02 -0400 | [diff] [blame] | 3203 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3204 | c_nritems = btrfs_header_nritems(c); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3205 | mid = (c_nritems + 1) / 2; |
| 3206 | btrfs_node_key(c, &disk_key, mid); |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 3207 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3208 | split = btrfs_alloc_free_block(trans, root, root->nodesize, 0, |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3209 | root->root_key.objectid, |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 3210 | &disk_key, level, c->start, 0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3211 | if (IS_ERR(split)) |
| 3212 | return PTR_ERR(split); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 3213 | |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 3214 | root_add_used(root, root->nodesize); |
| 3215 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3216 | memset_extent_buffer(split, 0, 0, sizeof(struct btrfs_header)); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3217 | btrfs_set_header_level(split, btrfs_header_level(c)); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3218 | btrfs_set_header_bytenr(split, split->start); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3219 | btrfs_set_header_generation(split, trans->transid); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3220 | btrfs_set_header_backref_rev(split, BTRFS_MIXED_BACKREF_REV); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3221 | btrfs_set_header_owner(split, root->root_key.objectid); |
| 3222 | write_extent_buffer(split, root->fs_info->fsid, |
| 3223 | (unsigned long)btrfs_header_fsid(split), |
| 3224 | BTRFS_FSID_SIZE); |
Chris Mason | e17cade | 2008-04-15 15:41:47 -0400 | [diff] [blame] | 3225 | write_extent_buffer(split, root->fs_info->chunk_tree_uuid, |
| 3226 | (unsigned long)btrfs_header_chunk_tree_uuid(split), |
| 3227 | BTRFS_UUID_SIZE); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3228 | |
Jan Schmidt | f230475 | 2012-05-26 11:43:17 +0200 | [diff] [blame] | 3229 | tree_mod_log_eb_copy(root->fs_info, split, c, 0, mid, c_nritems - mid); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3230 | copy_extent_buffer(split, c, |
| 3231 | btrfs_node_key_ptr_offset(0), |
| 3232 | btrfs_node_key_ptr_offset(mid), |
| 3233 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); |
| 3234 | btrfs_set_header_nritems(split, c_nritems - mid); |
| 3235 | btrfs_set_header_nritems(c, mid); |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 3236 | ret = 0; |
| 3237 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3238 | btrfs_mark_buffer_dirty(c); |
| 3239 | btrfs_mark_buffer_dirty(split); |
| 3240 | |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 3241 | insert_ptr(trans, root, path, &disk_key, split->start, |
Jan Schmidt | c3e0696 | 2012-06-21 11:01:06 +0200 | [diff] [blame] | 3242 | path->slots[level + 1] + 1, level + 1); |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 3243 | |
Chris Mason | 5de08d7 | 2007-02-24 06:24:44 -0500 | [diff] [blame] | 3244 | if (path->slots[level] >= mid) { |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3245 | path->slots[level] -= mid; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3246 | btrfs_tree_unlock(c); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3247 | free_extent_buffer(c); |
| 3248 | path->nodes[level] = split; |
Chris Mason | 5c680ed | 2007-02-22 11:39:13 -0500 | [diff] [blame] | 3249 | path->slots[level + 1] += 1; |
| 3250 | } else { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3251 | btrfs_tree_unlock(split); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3252 | free_extent_buffer(split); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3253 | } |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 3254 | return ret; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3255 | } |
| 3256 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3257 | /* |
| 3258 | * how many bytes are required to store the items in a leaf. start |
| 3259 | * and nr indicate which items in the leaf to check. This totals up the |
| 3260 | * space used both by the item structs and the item data |
| 3261 | */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3262 | static int leaf_space_used(struct extent_buffer *l, int start, int nr) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3263 | { |
| 3264 | int data_len; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3265 | int nritems = btrfs_header_nritems(l); |
Chris Mason | d4dbff9 | 2007-04-04 14:08:15 -0400 | [diff] [blame] | 3266 | int end = min(nritems, start + nr) - 1; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3267 | |
| 3268 | if (!nr) |
| 3269 | return 0; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3270 | data_len = btrfs_item_end_nr(l, start); |
| 3271 | data_len = data_len - btrfs_item_offset_nr(l, end); |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 3272 | data_len += sizeof(struct btrfs_item) * nr; |
Chris Mason | d4dbff9 | 2007-04-04 14:08:15 -0400 | [diff] [blame] | 3273 | WARN_ON(data_len < 0); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3274 | return data_len; |
| 3275 | } |
| 3276 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3277 | /* |
Chris Mason | d4dbff9 | 2007-04-04 14:08:15 -0400 | [diff] [blame] | 3278 | * The space between the end of the leaf items and |
| 3279 | * the start of the leaf data. IOW, how much room |
| 3280 | * the leaf has left for both items and data |
| 3281 | */ |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3282 | noinline int btrfs_leaf_free_space(struct btrfs_root *root, |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 3283 | struct extent_buffer *leaf) |
Chris Mason | d4dbff9 | 2007-04-04 14:08:15 -0400 | [diff] [blame] | 3284 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3285 | int nritems = btrfs_header_nritems(leaf); |
| 3286 | int ret; |
| 3287 | ret = BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems); |
| 3288 | if (ret < 0) { |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3289 | printk(KERN_CRIT "leaf free space ret %d, leaf data size %lu, " |
| 3290 | "used %d nritems %d\n", |
Jens Axboe | ae2f541 | 2007-10-19 09:22:59 -0400 | [diff] [blame] | 3291 | ret, (unsigned long) BTRFS_LEAF_DATA_SIZE(root), |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3292 | leaf_space_used(leaf, 0, nritems), nritems); |
| 3293 | } |
| 3294 | return ret; |
Chris Mason | d4dbff9 | 2007-04-04 14:08:15 -0400 | [diff] [blame] | 3295 | } |
| 3296 | |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3297 | /* |
| 3298 | * min slot controls the lowest index we're willing to push to the |
| 3299 | * right. We'll push up to and including min_slot, but no lower |
| 3300 | */ |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3301 | static noinline int __push_leaf_right(struct btrfs_trans_handle *trans, |
| 3302 | struct btrfs_root *root, |
| 3303 | struct btrfs_path *path, |
| 3304 | int data_size, int empty, |
| 3305 | struct extent_buffer *right, |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3306 | int free_space, u32 left_nritems, |
| 3307 | u32 min_slot) |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3308 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3309 | struct extent_buffer *left = path->nodes[0]; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3310 | struct extent_buffer *upper = path->nodes[1]; |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 3311 | struct btrfs_map_token token; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3312 | struct btrfs_disk_key disk_key; |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3313 | int slot; |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3314 | u32 i; |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3315 | int push_space = 0; |
| 3316 | int push_items = 0; |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 3317 | struct btrfs_item *item; |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3318 | u32 nr; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 3319 | u32 right_nritems; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3320 | u32 data_end; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3321 | u32 this_item_size; |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3322 | |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 3323 | btrfs_init_map_token(&token); |
| 3324 | |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3325 | if (empty) |
| 3326 | nr = 0; |
| 3327 | else |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3328 | nr = max_t(u32, 1, min_slot); |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3329 | |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3330 | if (path->slots[0] >= left_nritems) |
Yan Zheng | 87b29b2 | 2008-12-17 10:21:48 -0500 | [diff] [blame] | 3331 | push_space += data_size; |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3332 | |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3333 | slot = path->slots[1]; |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3334 | i = left_nritems - 1; |
| 3335 | while (i >= nr) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3336 | item = btrfs_item_nr(left, i); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3337 | |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3338 | if (!empty && push_items > 0) { |
| 3339 | if (path->slots[0] > i) |
| 3340 | break; |
| 3341 | if (path->slots[0] == i) { |
| 3342 | int space = btrfs_leaf_free_space(root, left); |
| 3343 | if (space + push_space * 2 > free_space) |
| 3344 | break; |
| 3345 | } |
| 3346 | } |
| 3347 | |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3348 | if (path->slots[0] == i) |
Yan Zheng | 87b29b2 | 2008-12-17 10:21:48 -0500 | [diff] [blame] | 3349 | push_space += data_size; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3350 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3351 | this_item_size = btrfs_item_size(left, item); |
| 3352 | if (this_item_size + sizeof(*item) + push_space > free_space) |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3353 | break; |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3354 | |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3355 | push_items++; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3356 | push_space += this_item_size + sizeof(*item); |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3357 | if (i == 0) |
| 3358 | break; |
| 3359 | i--; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3360 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3361 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3362 | if (push_items == 0) |
| 3363 | goto out_unlock; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3364 | |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3365 | if (!empty && push_items == left_nritems) |
Chris Mason | a429e51 | 2007-04-18 16:15:28 -0400 | [diff] [blame] | 3366 | WARN_ON(1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3367 | |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3368 | /* push left to right */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3369 | right_nritems = btrfs_header_nritems(right); |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3370 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3371 | push_space = btrfs_item_end_nr(left, left_nritems - push_items); |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 3372 | push_space -= leaf_data_end(root, left); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3373 | |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3374 | /* make room in the right data area */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3375 | data_end = leaf_data_end(root, right); |
| 3376 | memmove_extent_buffer(right, |
| 3377 | btrfs_leaf_data(right) + data_end - push_space, |
| 3378 | btrfs_leaf_data(right) + data_end, |
| 3379 | BTRFS_LEAF_DATA_SIZE(root) - data_end); |
| 3380 | |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3381 | /* copy from the left data area */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3382 | copy_extent_buffer(right, left, btrfs_leaf_data(right) + |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 3383 | BTRFS_LEAF_DATA_SIZE(root) - push_space, |
| 3384 | btrfs_leaf_data(left) + leaf_data_end(root, left), |
| 3385 | push_space); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3386 | |
| 3387 | memmove_extent_buffer(right, btrfs_item_nr_offset(push_items), |
| 3388 | btrfs_item_nr_offset(0), |
| 3389 | right_nritems * sizeof(struct btrfs_item)); |
| 3390 | |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3391 | /* copy the items from left to right */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3392 | copy_extent_buffer(right, left, btrfs_item_nr_offset(0), |
| 3393 | btrfs_item_nr_offset(left_nritems - push_items), |
| 3394 | push_items * sizeof(struct btrfs_item)); |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3395 | |
| 3396 | /* update the item pointers */ |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 3397 | right_nritems += push_items; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3398 | btrfs_set_header_nritems(right, right_nritems); |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 3399 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 3400 | for (i = 0; i < right_nritems; i++) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3401 | item = btrfs_item_nr(right, i); |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 3402 | push_space -= btrfs_token_item_size(right, item, &token); |
| 3403 | btrfs_set_token_item_offset(right, item, push_space, &token); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3404 | } |
| 3405 | |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 3406 | left_nritems -= push_items; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3407 | btrfs_set_header_nritems(left, left_nritems); |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3408 | |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3409 | if (left_nritems) |
| 3410 | btrfs_mark_buffer_dirty(left); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 3411 | else |
| 3412 | clean_tree_block(trans, root, left); |
| 3413 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3414 | btrfs_mark_buffer_dirty(right); |
Chris Mason | a429e51 | 2007-04-18 16:15:28 -0400 | [diff] [blame] | 3415 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3416 | btrfs_item_key(right, &disk_key, 0); |
| 3417 | btrfs_set_node_key(upper, &disk_key, slot + 1); |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 3418 | btrfs_mark_buffer_dirty(upper); |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 3419 | |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3420 | /* then fixup the leaf pointer in the path */ |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 3421 | if (path->slots[0] >= left_nritems) { |
| 3422 | path->slots[0] -= left_nritems; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3423 | if (btrfs_header_nritems(path->nodes[0]) == 0) |
| 3424 | clean_tree_block(trans, root, path->nodes[0]); |
| 3425 | btrfs_tree_unlock(path->nodes[0]); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3426 | free_extent_buffer(path->nodes[0]); |
| 3427 | path->nodes[0] = right; |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3428 | path->slots[1] += 1; |
| 3429 | } else { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3430 | btrfs_tree_unlock(right); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3431 | free_extent_buffer(right); |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3432 | } |
| 3433 | return 0; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3434 | |
| 3435 | out_unlock: |
| 3436 | btrfs_tree_unlock(right); |
| 3437 | free_extent_buffer(right); |
| 3438 | return 1; |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3439 | } |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3440 | |
Chris Mason | 00ec4c5 | 2007-02-24 12:47:20 -0500 | [diff] [blame] | 3441 | /* |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3442 | * push some data in the path leaf to the right, trying to free up at |
| 3443 | * least data_size bytes. returns zero if the push worked, nonzero otherwise |
| 3444 | * |
| 3445 | * returns 1 if the push failed because the other node didn't have enough |
| 3446 | * room, 0 if everything worked out and < 0 if there were major errors. |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3447 | * |
| 3448 | * this will push starting from min_slot to the end of the leaf. It won't |
| 3449 | * push any slot lower than min_slot |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3450 | */ |
| 3451 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3452 | *root, struct btrfs_path *path, |
| 3453 | int min_data_size, int data_size, |
| 3454 | int empty, u32 min_slot) |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3455 | { |
| 3456 | struct extent_buffer *left = path->nodes[0]; |
| 3457 | struct extent_buffer *right; |
| 3458 | struct extent_buffer *upper; |
| 3459 | int slot; |
| 3460 | int free_space; |
| 3461 | u32 left_nritems; |
| 3462 | int ret; |
| 3463 | |
| 3464 | if (!path->nodes[1]) |
| 3465 | return 1; |
| 3466 | |
| 3467 | slot = path->slots[1]; |
| 3468 | upper = path->nodes[1]; |
| 3469 | if (slot >= btrfs_header_nritems(upper) - 1) |
| 3470 | return 1; |
| 3471 | |
| 3472 | btrfs_assert_tree_locked(path->nodes[1]); |
| 3473 | |
| 3474 | right = read_node_slot(root, upper, slot + 1); |
Tsutomu Itoh | 91ca338 | 2011-01-05 02:32:22 +0000 | [diff] [blame] | 3475 | if (right == NULL) |
| 3476 | return 1; |
| 3477 | |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3478 | btrfs_tree_lock(right); |
| 3479 | btrfs_set_lock_blocking(right); |
| 3480 | |
| 3481 | free_space = btrfs_leaf_free_space(root, right); |
| 3482 | if (free_space < data_size) |
| 3483 | goto out_unlock; |
| 3484 | |
| 3485 | /* cow and double check */ |
| 3486 | ret = btrfs_cow_block(trans, root, right, upper, |
| 3487 | slot + 1, &right); |
| 3488 | if (ret) |
| 3489 | goto out_unlock; |
| 3490 | |
| 3491 | free_space = btrfs_leaf_free_space(root, right); |
| 3492 | if (free_space < data_size) |
| 3493 | goto out_unlock; |
| 3494 | |
| 3495 | left_nritems = btrfs_header_nritems(left); |
| 3496 | if (left_nritems == 0) |
| 3497 | goto out_unlock; |
| 3498 | |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3499 | return __push_leaf_right(trans, root, path, min_data_size, empty, |
| 3500 | right, free_space, left_nritems, min_slot); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3501 | out_unlock: |
| 3502 | btrfs_tree_unlock(right); |
| 3503 | free_extent_buffer(right); |
| 3504 | return 1; |
| 3505 | } |
| 3506 | |
| 3507 | /* |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3508 | * push some data in the path leaf to the left, trying to free up at |
| 3509 | * least data_size bytes. returns zero if the push worked, nonzero otherwise |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3510 | * |
| 3511 | * max_slot can put a limit on how far into the leaf we'll push items. The |
| 3512 | * item at 'max_slot' won't be touched. Use (u32)-1 to make us do all the |
| 3513 | * items |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3514 | */ |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3515 | static noinline int __push_leaf_left(struct btrfs_trans_handle *trans, |
| 3516 | struct btrfs_root *root, |
| 3517 | struct btrfs_path *path, int data_size, |
| 3518 | int empty, struct extent_buffer *left, |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3519 | int free_space, u32 right_nritems, |
| 3520 | u32 max_slot) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3521 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3522 | struct btrfs_disk_key disk_key; |
| 3523 | struct extent_buffer *right = path->nodes[0]; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3524 | int i; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3525 | int push_space = 0; |
| 3526 | int push_items = 0; |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 3527 | struct btrfs_item *item; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 3528 | u32 old_left_nritems; |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3529 | u32 nr; |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 3530 | int ret = 0; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3531 | u32 this_item_size; |
| 3532 | u32 old_left_item_size; |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 3533 | struct btrfs_map_token token; |
| 3534 | |
| 3535 | btrfs_init_map_token(&token); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3536 | |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3537 | if (empty) |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3538 | nr = min(right_nritems, max_slot); |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3539 | else |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3540 | nr = min(right_nritems - 1, max_slot); |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3541 | |
| 3542 | for (i = 0; i < nr; i++) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3543 | item = btrfs_item_nr(right, i); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3544 | |
Zheng Yan | 31840ae | 2008-09-23 13:14:14 -0400 | [diff] [blame] | 3545 | if (!empty && push_items > 0) { |
| 3546 | if (path->slots[0] < i) |
| 3547 | break; |
| 3548 | if (path->slots[0] == i) { |
| 3549 | int space = btrfs_leaf_free_space(root, right); |
| 3550 | if (space + push_space * 2 > free_space) |
| 3551 | break; |
| 3552 | } |
| 3553 | } |
| 3554 | |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3555 | if (path->slots[0] == i) |
Yan Zheng | 87b29b2 | 2008-12-17 10:21:48 -0500 | [diff] [blame] | 3556 | push_space += data_size; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3557 | |
| 3558 | this_item_size = btrfs_item_size(right, item); |
| 3559 | if (this_item_size + sizeof(*item) + push_space > free_space) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3560 | break; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3561 | |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3562 | push_items++; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3563 | push_space += this_item_size + sizeof(*item); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3564 | } |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3565 | |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3566 | if (push_items == 0) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3567 | ret = 1; |
| 3568 | goto out; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3569 | } |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3570 | if (!empty && push_items == btrfs_header_nritems(right)) |
Chris Mason | a429e51 | 2007-04-18 16:15:28 -0400 | [diff] [blame] | 3571 | WARN_ON(1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3572 | |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3573 | /* push data from right to left */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3574 | copy_extent_buffer(left, right, |
| 3575 | btrfs_item_nr_offset(btrfs_header_nritems(left)), |
| 3576 | btrfs_item_nr_offset(0), |
| 3577 | push_items * sizeof(struct btrfs_item)); |
| 3578 | |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 3579 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3580 | btrfs_item_offset_nr(right, push_items - 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3581 | |
| 3582 | copy_extent_buffer(left, right, btrfs_leaf_data(left) + |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 3583 | leaf_data_end(root, left) - push_space, |
| 3584 | btrfs_leaf_data(right) + |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3585 | btrfs_item_offset_nr(right, push_items - 1), |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 3586 | push_space); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3587 | old_left_nritems = btrfs_header_nritems(left); |
Yan Zheng | 87b29b2 | 2008-12-17 10:21:48 -0500 | [diff] [blame] | 3588 | BUG_ON(old_left_nritems <= 0); |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 3589 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3590 | old_left_item_size = btrfs_item_offset_nr(left, old_left_nritems - 1); |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 3591 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3592 | u32 ioff; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3593 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3594 | item = btrfs_item_nr(left, i); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3595 | |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 3596 | ioff = btrfs_token_item_offset(left, item, &token); |
| 3597 | btrfs_set_token_item_offset(left, item, |
| 3598 | ioff - (BTRFS_LEAF_DATA_SIZE(root) - old_left_item_size), |
| 3599 | &token); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3600 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3601 | btrfs_set_header_nritems(left, old_left_nritems + push_items); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3602 | |
| 3603 | /* fixup right node */ |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3604 | if (push_items > right_nritems) { |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 3605 | printk(KERN_CRIT "push items %d nr %u\n", push_items, |
| 3606 | right_nritems); |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3607 | WARN_ON(1); |
| 3608 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3609 | |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3610 | if (push_items < right_nritems) { |
| 3611 | push_space = btrfs_item_offset_nr(right, push_items - 1) - |
| 3612 | leaf_data_end(root, right); |
| 3613 | memmove_extent_buffer(right, btrfs_leaf_data(right) + |
| 3614 | BTRFS_LEAF_DATA_SIZE(root) - push_space, |
| 3615 | btrfs_leaf_data(right) + |
| 3616 | leaf_data_end(root, right), push_space); |
| 3617 | |
| 3618 | memmove_extent_buffer(right, btrfs_item_nr_offset(0), |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3619 | btrfs_item_nr_offset(push_items), |
| 3620 | (btrfs_header_nritems(right) - push_items) * |
| 3621 | sizeof(struct btrfs_item)); |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3622 | } |
Yan | eef1c49 | 2007-11-26 10:58:13 -0500 | [diff] [blame] | 3623 | right_nritems -= push_items; |
| 3624 | btrfs_set_header_nritems(right, right_nritems); |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 3625 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3626 | for (i = 0; i < right_nritems; i++) { |
| 3627 | item = btrfs_item_nr(right, i); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3628 | |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 3629 | push_space = push_space - btrfs_token_item_size(right, |
| 3630 | item, &token); |
| 3631 | btrfs_set_token_item_offset(right, item, push_space, &token); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3632 | } |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 3633 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3634 | btrfs_mark_buffer_dirty(left); |
Chris Mason | 34a3821 | 2007-11-07 13:31:03 -0500 | [diff] [blame] | 3635 | if (right_nritems) |
| 3636 | btrfs_mark_buffer_dirty(right); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 3637 | else |
| 3638 | clean_tree_block(trans, root, right); |
Chris Mason | 098f59c | 2007-05-11 11:33:21 -0400 | [diff] [blame] | 3639 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3640 | btrfs_item_key(right, &disk_key, 0); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 3641 | fixup_low_keys(trans, root, path, &disk_key, 1); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3642 | |
| 3643 | /* then fixup the leaf pointer in the path */ |
| 3644 | if (path->slots[0] < push_items) { |
| 3645 | path->slots[0] += old_left_nritems; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3646 | btrfs_tree_unlock(path->nodes[0]); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3647 | free_extent_buffer(path->nodes[0]); |
| 3648 | path->nodes[0] = left; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3649 | path->slots[1] -= 1; |
| 3650 | } else { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3651 | btrfs_tree_unlock(left); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3652 | free_extent_buffer(left); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3653 | path->slots[0] -= push_items; |
| 3654 | } |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 3655 | BUG_ON(path->slots[0] < 0); |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 3656 | return ret; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3657 | out: |
| 3658 | btrfs_tree_unlock(left); |
| 3659 | free_extent_buffer(left); |
| 3660 | return ret; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3661 | } |
| 3662 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3663 | /* |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3664 | * push some data in the path leaf to the left, trying to free up at |
| 3665 | * least data_size bytes. returns zero if the push worked, nonzero otherwise |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3666 | * |
| 3667 | * max_slot can put a limit on how far into the leaf we'll push items. The |
| 3668 | * item at 'max_slot' won't be touched. Use (u32)-1 to make us push all the |
| 3669 | * items |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3670 | */ |
| 3671 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3672 | *root, struct btrfs_path *path, int min_data_size, |
| 3673 | int data_size, int empty, u32 max_slot) |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3674 | { |
| 3675 | struct extent_buffer *right = path->nodes[0]; |
| 3676 | struct extent_buffer *left; |
| 3677 | int slot; |
| 3678 | int free_space; |
| 3679 | u32 right_nritems; |
| 3680 | int ret = 0; |
| 3681 | |
| 3682 | slot = path->slots[1]; |
| 3683 | if (slot == 0) |
| 3684 | return 1; |
| 3685 | if (!path->nodes[1]) |
| 3686 | return 1; |
| 3687 | |
| 3688 | right_nritems = btrfs_header_nritems(right); |
| 3689 | if (right_nritems == 0) |
| 3690 | return 1; |
| 3691 | |
| 3692 | btrfs_assert_tree_locked(path->nodes[1]); |
| 3693 | |
| 3694 | left = read_node_slot(root, path->nodes[1], slot - 1); |
Tsutomu Itoh | 91ca338 | 2011-01-05 02:32:22 +0000 | [diff] [blame] | 3695 | if (left == NULL) |
| 3696 | return 1; |
| 3697 | |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3698 | btrfs_tree_lock(left); |
| 3699 | btrfs_set_lock_blocking(left); |
| 3700 | |
| 3701 | free_space = btrfs_leaf_free_space(root, left); |
| 3702 | if (free_space < data_size) { |
| 3703 | ret = 1; |
| 3704 | goto out; |
| 3705 | } |
| 3706 | |
| 3707 | /* cow and double check */ |
| 3708 | ret = btrfs_cow_block(trans, root, left, |
| 3709 | path->nodes[1], slot - 1, &left); |
| 3710 | if (ret) { |
| 3711 | /* we hit -ENOSPC, but it isn't fatal here */ |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 3712 | if (ret == -ENOSPC) |
| 3713 | ret = 1; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3714 | goto out; |
| 3715 | } |
| 3716 | |
| 3717 | free_space = btrfs_leaf_free_space(root, left); |
| 3718 | if (free_space < data_size) { |
| 3719 | ret = 1; |
| 3720 | goto out; |
| 3721 | } |
| 3722 | |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3723 | return __push_leaf_left(trans, root, path, min_data_size, |
| 3724 | empty, left, free_space, right_nritems, |
| 3725 | max_slot); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3726 | out: |
| 3727 | btrfs_tree_unlock(left); |
| 3728 | free_extent_buffer(left); |
| 3729 | return ret; |
| 3730 | } |
| 3731 | |
| 3732 | /* |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3733 | * split the path's leaf in two, making sure there is at least data_size |
| 3734 | * available for the resulting leaf level of the path. |
| 3735 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 3736 | static noinline void copy_for_split(struct btrfs_trans_handle *trans, |
| 3737 | struct btrfs_root *root, |
| 3738 | struct btrfs_path *path, |
| 3739 | struct extent_buffer *l, |
| 3740 | struct extent_buffer *right, |
| 3741 | int slot, int mid, int nritems) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3742 | { |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3743 | int data_copy_size; |
| 3744 | int rt_data_off; |
| 3745 | int i; |
Chris Mason | d4dbff9 | 2007-04-04 14:08:15 -0400 | [diff] [blame] | 3746 | struct btrfs_disk_key disk_key; |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 3747 | struct btrfs_map_token token; |
| 3748 | |
| 3749 | btrfs_init_map_token(&token); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3750 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3751 | nritems = nritems - mid; |
| 3752 | btrfs_set_header_nritems(right, nritems); |
| 3753 | data_copy_size = btrfs_item_end_nr(l, mid) - leaf_data_end(root, l); |
| 3754 | |
| 3755 | copy_extent_buffer(right, l, btrfs_item_nr_offset(0), |
| 3756 | btrfs_item_nr_offset(mid), |
| 3757 | nritems * sizeof(struct btrfs_item)); |
| 3758 | |
| 3759 | copy_extent_buffer(right, l, |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 3760 | btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - |
| 3761 | data_copy_size, btrfs_leaf_data(l) + |
| 3762 | leaf_data_end(root, l), data_copy_size); |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3763 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3764 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - |
| 3765 | btrfs_item_end_nr(l, mid); |
| 3766 | |
| 3767 | for (i = 0; i < nritems; i++) { |
| 3768 | struct btrfs_item *item = btrfs_item_nr(right, i); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 3769 | u32 ioff; |
| 3770 | |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 3771 | ioff = btrfs_token_item_offset(right, item, &token); |
| 3772 | btrfs_set_token_item_offset(right, item, |
| 3773 | ioff + rt_data_off, &token); |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 3774 | } |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 3775 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3776 | btrfs_set_header_nritems(l, mid); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3777 | btrfs_item_key(right, &disk_key, 0); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 3778 | insert_ptr(trans, root, path, &disk_key, right->start, |
Jan Schmidt | c3e0696 | 2012-06-21 11:01:06 +0200 | [diff] [blame] | 3779 | path->slots[1] + 1, 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3780 | |
| 3781 | btrfs_mark_buffer_dirty(right); |
| 3782 | btrfs_mark_buffer_dirty(l); |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 3783 | BUG_ON(path->slots[0] != slot); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3784 | |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3785 | if (mid <= slot) { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3786 | btrfs_tree_unlock(path->nodes[0]); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3787 | free_extent_buffer(path->nodes[0]); |
| 3788 | path->nodes[0] = right; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 3789 | path->slots[0] -= mid; |
| 3790 | path->slots[1] += 1; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3791 | } else { |
| 3792 | btrfs_tree_unlock(right); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3793 | free_extent_buffer(right); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 3794 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 3795 | |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 3796 | BUG_ON(path->slots[0] < 0); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3797 | } |
| 3798 | |
| 3799 | /* |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3800 | * double splits happen when we need to insert a big item in the middle |
| 3801 | * of a leaf. A double split can leave us with 3 mostly empty leaves: |
| 3802 | * leaf: [ slots 0 - N] [ our target ] [ N + 1 - total in leaf ] |
| 3803 | * A B C |
| 3804 | * |
| 3805 | * We avoid this by trying to push the items on either side of our target |
| 3806 | * into the adjacent leaves. If all goes well we can avoid the double split |
| 3807 | * completely. |
| 3808 | */ |
| 3809 | static noinline int push_for_double_split(struct btrfs_trans_handle *trans, |
| 3810 | struct btrfs_root *root, |
| 3811 | struct btrfs_path *path, |
| 3812 | int data_size) |
| 3813 | { |
| 3814 | int ret; |
| 3815 | int progress = 0; |
| 3816 | int slot; |
| 3817 | u32 nritems; |
| 3818 | |
| 3819 | slot = path->slots[0]; |
| 3820 | |
| 3821 | /* |
| 3822 | * try to push all the items after our slot into the |
| 3823 | * right leaf |
| 3824 | */ |
| 3825 | ret = push_leaf_right(trans, root, path, 1, data_size, 0, slot); |
| 3826 | if (ret < 0) |
| 3827 | return ret; |
| 3828 | |
| 3829 | if (ret == 0) |
| 3830 | progress++; |
| 3831 | |
| 3832 | nritems = btrfs_header_nritems(path->nodes[0]); |
| 3833 | /* |
| 3834 | * our goal is to get our slot at the start or end of a leaf. If |
| 3835 | * we've done so we're done |
| 3836 | */ |
| 3837 | if (path->slots[0] == 0 || path->slots[0] == nritems) |
| 3838 | return 0; |
| 3839 | |
| 3840 | if (btrfs_leaf_free_space(root, path->nodes[0]) >= data_size) |
| 3841 | return 0; |
| 3842 | |
| 3843 | /* try to push all the items before our slot into the next leaf */ |
| 3844 | slot = path->slots[0]; |
| 3845 | ret = push_leaf_left(trans, root, path, 1, data_size, 0, slot); |
| 3846 | if (ret < 0) |
| 3847 | return ret; |
| 3848 | |
| 3849 | if (ret == 0) |
| 3850 | progress++; |
| 3851 | |
| 3852 | if (progress) |
| 3853 | return 0; |
| 3854 | return 1; |
| 3855 | } |
| 3856 | |
| 3857 | /* |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3858 | * split the path's leaf in two, making sure there is at least data_size |
| 3859 | * available for the resulting leaf level of the path. |
| 3860 | * |
| 3861 | * returns 0 if all went well and < 0 on failure. |
| 3862 | */ |
| 3863 | static noinline int split_leaf(struct btrfs_trans_handle *trans, |
| 3864 | struct btrfs_root *root, |
| 3865 | struct btrfs_key *ins_key, |
| 3866 | struct btrfs_path *path, int data_size, |
| 3867 | int extend) |
| 3868 | { |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3869 | struct btrfs_disk_key disk_key; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3870 | struct extent_buffer *l; |
| 3871 | u32 nritems; |
| 3872 | int mid; |
| 3873 | int slot; |
| 3874 | struct extent_buffer *right; |
| 3875 | int ret = 0; |
| 3876 | int wret; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3877 | int split; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3878 | int num_doubles = 0; |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3879 | int tried_avoid_double = 0; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3880 | |
Yan, Zheng | a571952 | 2009-09-24 09:17:31 -0400 | [diff] [blame] | 3881 | l = path->nodes[0]; |
| 3882 | slot = path->slots[0]; |
| 3883 | if (extend && data_size + btrfs_item_size_nr(l, slot) + |
| 3884 | sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root)) |
| 3885 | return -EOVERFLOW; |
| 3886 | |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3887 | /* first try to make some room by pushing left and right */ |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3888 | if (data_size) { |
| 3889 | wret = push_leaf_right(trans, root, path, data_size, |
| 3890 | data_size, 0, 0); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3891 | if (wret < 0) |
| 3892 | return wret; |
| 3893 | if (wret) { |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3894 | wret = push_leaf_left(trans, root, path, data_size, |
| 3895 | data_size, 0, (u32)-1); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3896 | if (wret < 0) |
| 3897 | return wret; |
| 3898 | } |
| 3899 | l = path->nodes[0]; |
| 3900 | |
| 3901 | /* did the pushes work? */ |
| 3902 | if (btrfs_leaf_free_space(root, l) >= data_size) |
| 3903 | return 0; |
| 3904 | } |
| 3905 | |
| 3906 | if (!path->nodes[1]) { |
| 3907 | ret = insert_new_root(trans, root, path, 1); |
| 3908 | if (ret) |
| 3909 | return ret; |
| 3910 | } |
| 3911 | again: |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3912 | split = 1; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3913 | l = path->nodes[0]; |
| 3914 | slot = path->slots[0]; |
| 3915 | nritems = btrfs_header_nritems(l); |
| 3916 | mid = (nritems + 1) / 2; |
| 3917 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3918 | if (mid <= slot) { |
| 3919 | if (nritems == 1 || |
| 3920 | leaf_space_used(l, mid, nritems - mid) + data_size > |
| 3921 | BTRFS_LEAF_DATA_SIZE(root)) { |
| 3922 | if (slot >= nritems) { |
| 3923 | split = 0; |
| 3924 | } else { |
| 3925 | mid = slot; |
| 3926 | if (mid != nritems && |
| 3927 | leaf_space_used(l, mid, nritems - mid) + |
| 3928 | data_size > BTRFS_LEAF_DATA_SIZE(root)) { |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3929 | if (data_size && !tried_avoid_double) |
| 3930 | goto push_for_double; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3931 | split = 2; |
| 3932 | } |
| 3933 | } |
| 3934 | } |
| 3935 | } else { |
| 3936 | if (leaf_space_used(l, 0, mid) + data_size > |
| 3937 | BTRFS_LEAF_DATA_SIZE(root)) { |
| 3938 | if (!extend && data_size && slot == 0) { |
| 3939 | split = 0; |
| 3940 | } else if ((extend || !data_size) && slot == 0) { |
| 3941 | mid = 1; |
| 3942 | } else { |
| 3943 | mid = slot; |
| 3944 | if (mid != nritems && |
| 3945 | leaf_space_used(l, mid, nritems - mid) + |
| 3946 | data_size > BTRFS_LEAF_DATA_SIZE(root)) { |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 3947 | if (data_size && !tried_avoid_double) |
| 3948 | goto push_for_double; |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3949 | split = 2 ; |
| 3950 | } |
| 3951 | } |
| 3952 | } |
| 3953 | } |
| 3954 | |
| 3955 | if (split == 0) |
| 3956 | btrfs_cpu_key_to_disk(&disk_key, ins_key); |
| 3957 | else |
| 3958 | btrfs_item_key(l, &disk_key, mid); |
| 3959 | |
| 3960 | right = btrfs_alloc_free_block(trans, root, root->leafsize, 0, |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3961 | root->root_key.objectid, |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 3962 | &disk_key, 0, l->start, 0); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 3963 | if (IS_ERR(right)) |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3964 | return PTR_ERR(right); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 3965 | |
| 3966 | root_add_used(root, root->leafsize); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3967 | |
| 3968 | memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header)); |
| 3969 | btrfs_set_header_bytenr(right, right->start); |
| 3970 | btrfs_set_header_generation(right, trans->transid); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3971 | btrfs_set_header_backref_rev(right, BTRFS_MIXED_BACKREF_REV); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 3972 | btrfs_set_header_owner(right, root->root_key.objectid); |
| 3973 | btrfs_set_header_level(right, 0); |
| 3974 | write_extent_buffer(right, root->fs_info->fsid, |
| 3975 | (unsigned long)btrfs_header_fsid(right), |
| 3976 | BTRFS_FSID_SIZE); |
| 3977 | |
| 3978 | write_extent_buffer(right, root->fs_info->chunk_tree_uuid, |
| 3979 | (unsigned long)btrfs_header_chunk_tree_uuid(right), |
| 3980 | BTRFS_UUID_SIZE); |
| 3981 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3982 | if (split == 0) { |
| 3983 | if (mid <= slot) { |
| 3984 | btrfs_set_header_nritems(right, 0); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 3985 | insert_ptr(trans, root, path, &disk_key, right->start, |
Jan Schmidt | c3e0696 | 2012-06-21 11:01:06 +0200 | [diff] [blame] | 3986 | path->slots[1] + 1, 1); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3987 | btrfs_tree_unlock(path->nodes[0]); |
| 3988 | free_extent_buffer(path->nodes[0]); |
| 3989 | path->nodes[0] = right; |
| 3990 | path->slots[0] = 0; |
| 3991 | path->slots[1] += 1; |
| 3992 | } else { |
| 3993 | btrfs_set_header_nritems(right, 0); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 3994 | insert_ptr(trans, root, path, &disk_key, right->start, |
Jan Schmidt | c3e0696 | 2012-06-21 11:01:06 +0200 | [diff] [blame] | 3995 | path->slots[1], 1); |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 3996 | btrfs_tree_unlock(path->nodes[0]); |
| 3997 | free_extent_buffer(path->nodes[0]); |
| 3998 | path->nodes[0] = right; |
| 3999 | path->slots[0] = 0; |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4000 | if (path->slots[1] == 0) |
| 4001 | fixup_low_keys(trans, root, path, |
| 4002 | &disk_key, 1); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4003 | } |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 4004 | btrfs_mark_buffer_dirty(right); |
| 4005 | return ret; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4006 | } |
| 4007 | |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4008 | copy_for_split(trans, root, path, l, right, slot, mid, nritems); |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4009 | |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 4010 | if (split == 2) { |
Chris Mason | cc0c553 | 2007-10-25 15:42:57 -0400 | [diff] [blame] | 4011 | BUG_ON(num_doubles != 0); |
| 4012 | num_doubles++; |
| 4013 | goto again; |
Chris Mason | 3326d1b | 2007-10-15 16:18:25 -0400 | [diff] [blame] | 4014 | } |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4015 | |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4016 | return 0; |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 4017 | |
| 4018 | push_for_double: |
| 4019 | push_for_double_split(trans, root, path, data_size); |
| 4020 | tried_avoid_double = 1; |
| 4021 | if (btrfs_leaf_free_space(root, path->nodes[0]) >= data_size) |
| 4022 | return 0; |
| 4023 | goto again; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4024 | } |
| 4025 | |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4026 | static noinline int setup_leaf_for_split(struct btrfs_trans_handle *trans, |
| 4027 | struct btrfs_root *root, |
| 4028 | struct btrfs_path *path, int ins_len) |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4029 | { |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4030 | struct btrfs_key key; |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4031 | struct extent_buffer *leaf; |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4032 | struct btrfs_file_extent_item *fi; |
| 4033 | u64 extent_len = 0; |
| 4034 | u32 item_size; |
| 4035 | int ret; |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4036 | |
| 4037 | leaf = path->nodes[0]; |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4038 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); |
| 4039 | |
| 4040 | BUG_ON(key.type != BTRFS_EXTENT_DATA_KEY && |
| 4041 | key.type != BTRFS_EXTENT_CSUM_KEY); |
| 4042 | |
| 4043 | if (btrfs_leaf_free_space(root, leaf) >= ins_len) |
| 4044 | return 0; |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4045 | |
| 4046 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4047 | if (key.type == BTRFS_EXTENT_DATA_KEY) { |
| 4048 | fi = btrfs_item_ptr(leaf, path->slots[0], |
| 4049 | struct btrfs_file_extent_item); |
| 4050 | extent_len = btrfs_file_extent_num_bytes(leaf, fi); |
| 4051 | } |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 4052 | btrfs_release_path(path); |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4053 | |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4054 | path->keep_locks = 1; |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4055 | path->search_for_split = 1; |
| 4056 | ret = btrfs_search_slot(trans, root, &key, path, 0, 1); |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4057 | path->search_for_split = 0; |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4058 | if (ret < 0) |
| 4059 | goto err; |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4060 | |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4061 | ret = -EAGAIN; |
| 4062 | leaf = path->nodes[0]; |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4063 | /* if our item isn't there or got smaller, return now */ |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4064 | if (ret > 0 || item_size != btrfs_item_size_nr(leaf, path->slots[0])) |
| 4065 | goto err; |
| 4066 | |
Chris Mason | 109f6ae | 2010-04-02 09:20:18 -0400 | [diff] [blame] | 4067 | /* the leaf has changed, it now has room. return now */ |
| 4068 | if (btrfs_leaf_free_space(root, path->nodes[0]) >= ins_len) |
| 4069 | goto err; |
| 4070 | |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4071 | if (key.type == BTRFS_EXTENT_DATA_KEY) { |
| 4072 | fi = btrfs_item_ptr(leaf, path->slots[0], |
| 4073 | struct btrfs_file_extent_item); |
| 4074 | if (extent_len != btrfs_file_extent_num_bytes(leaf, fi)) |
| 4075 | goto err; |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4076 | } |
| 4077 | |
Chris Mason | b947343 | 2009-03-13 11:00:37 -0400 | [diff] [blame] | 4078 | btrfs_set_path_blocking(path); |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4079 | ret = split_leaf(trans, root, &key, path, ins_len, 1); |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 4080 | if (ret) |
| 4081 | goto err; |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4082 | |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4083 | path->keep_locks = 0; |
Chris Mason | b947343 | 2009-03-13 11:00:37 -0400 | [diff] [blame] | 4084 | btrfs_unlock_up_safe(path, 1); |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4085 | return 0; |
| 4086 | err: |
| 4087 | path->keep_locks = 0; |
| 4088 | return ret; |
| 4089 | } |
| 4090 | |
| 4091 | static noinline int split_item(struct btrfs_trans_handle *trans, |
| 4092 | struct btrfs_root *root, |
| 4093 | struct btrfs_path *path, |
| 4094 | struct btrfs_key *new_key, |
| 4095 | unsigned long split_offset) |
| 4096 | { |
| 4097 | struct extent_buffer *leaf; |
| 4098 | struct btrfs_item *item; |
| 4099 | struct btrfs_item *new_item; |
| 4100 | int slot; |
| 4101 | char *buf; |
| 4102 | u32 nritems; |
| 4103 | u32 item_size; |
| 4104 | u32 orig_offset; |
| 4105 | struct btrfs_disk_key disk_key; |
| 4106 | |
Chris Mason | b947343 | 2009-03-13 11:00:37 -0400 | [diff] [blame] | 4107 | leaf = path->nodes[0]; |
| 4108 | BUG_ON(btrfs_leaf_free_space(root, leaf) < sizeof(struct btrfs_item)); |
| 4109 | |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 4110 | btrfs_set_path_blocking(path); |
| 4111 | |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4112 | item = btrfs_item_nr(leaf, path->slots[0]); |
| 4113 | orig_offset = btrfs_item_offset(leaf, item); |
| 4114 | item_size = btrfs_item_size(leaf, item); |
| 4115 | |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4116 | buf = kmalloc(item_size, GFP_NOFS); |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4117 | if (!buf) |
| 4118 | return -ENOMEM; |
| 4119 | |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4120 | read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf, |
| 4121 | path->slots[0]), item_size); |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4122 | |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4123 | slot = path->slots[0] + 1; |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4124 | nritems = btrfs_header_nritems(leaf); |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4125 | if (slot != nritems) { |
| 4126 | /* shift the items */ |
| 4127 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + 1), |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4128 | btrfs_item_nr_offset(slot), |
| 4129 | (nritems - slot) * sizeof(struct btrfs_item)); |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4130 | } |
| 4131 | |
| 4132 | btrfs_cpu_key_to_disk(&disk_key, new_key); |
| 4133 | btrfs_set_item_key(leaf, &disk_key, slot); |
| 4134 | |
| 4135 | new_item = btrfs_item_nr(leaf, slot); |
| 4136 | |
| 4137 | btrfs_set_item_offset(leaf, new_item, orig_offset); |
| 4138 | btrfs_set_item_size(leaf, new_item, item_size - split_offset); |
| 4139 | |
| 4140 | btrfs_set_item_offset(leaf, item, |
| 4141 | orig_offset + item_size - split_offset); |
| 4142 | btrfs_set_item_size(leaf, item, split_offset); |
| 4143 | |
| 4144 | btrfs_set_header_nritems(leaf, nritems + 1); |
| 4145 | |
| 4146 | /* write the data for the start of the original item */ |
| 4147 | write_extent_buffer(leaf, buf, |
| 4148 | btrfs_item_ptr_offset(leaf, path->slots[0]), |
| 4149 | split_offset); |
| 4150 | |
| 4151 | /* write the data for the new item */ |
| 4152 | write_extent_buffer(leaf, buf + split_offset, |
| 4153 | btrfs_item_ptr_offset(leaf, slot), |
| 4154 | item_size - split_offset); |
| 4155 | btrfs_mark_buffer_dirty(leaf); |
| 4156 | |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4157 | BUG_ON(btrfs_leaf_free_space(root, leaf) < 0); |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4158 | kfree(buf); |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4159 | return 0; |
| 4160 | } |
| 4161 | |
| 4162 | /* |
| 4163 | * This function splits a single item into two items, |
| 4164 | * giving 'new_key' to the new item and splitting the |
| 4165 | * old one at split_offset (from the start of the item). |
| 4166 | * |
| 4167 | * The path may be released by this operation. After |
| 4168 | * the split, the path is pointing to the old item. The |
| 4169 | * new item is going to be in the same node as the old one. |
| 4170 | * |
| 4171 | * Note, the item being split must be smaller enough to live alone on |
| 4172 | * a tree block with room for one extra struct btrfs_item |
| 4173 | * |
| 4174 | * This allows us to split the item in place, keeping a lock on the |
| 4175 | * leaf the entire time. |
| 4176 | */ |
| 4177 | int btrfs_split_item(struct btrfs_trans_handle *trans, |
| 4178 | struct btrfs_root *root, |
| 4179 | struct btrfs_path *path, |
| 4180 | struct btrfs_key *new_key, |
| 4181 | unsigned long split_offset) |
| 4182 | { |
| 4183 | int ret; |
| 4184 | ret = setup_leaf_for_split(trans, root, path, |
| 4185 | sizeof(struct btrfs_item)); |
| 4186 | if (ret) |
| 4187 | return ret; |
| 4188 | |
| 4189 | ret = split_item(trans, root, path, new_key, split_offset); |
Chris Mason | 459931e | 2008-12-10 09:10:46 -0500 | [diff] [blame] | 4190 | return ret; |
| 4191 | } |
| 4192 | |
| 4193 | /* |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4194 | * This function duplicate a item, giving 'new_key' to the new item. |
| 4195 | * It guarantees both items live in the same tree leaf and the new item |
| 4196 | * is contiguous with the original item. |
| 4197 | * |
| 4198 | * This allows us to split file extent in place, keeping a lock on the |
| 4199 | * leaf the entire time. |
| 4200 | */ |
| 4201 | int btrfs_duplicate_item(struct btrfs_trans_handle *trans, |
| 4202 | struct btrfs_root *root, |
| 4203 | struct btrfs_path *path, |
| 4204 | struct btrfs_key *new_key) |
| 4205 | { |
| 4206 | struct extent_buffer *leaf; |
| 4207 | int ret; |
| 4208 | u32 item_size; |
| 4209 | |
| 4210 | leaf = path->nodes[0]; |
| 4211 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); |
| 4212 | ret = setup_leaf_for_split(trans, root, path, |
| 4213 | item_size + sizeof(struct btrfs_item)); |
| 4214 | if (ret) |
| 4215 | return ret; |
| 4216 | |
| 4217 | path->slots[0]++; |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4218 | setup_items_for_insert(trans, root, path, new_key, &item_size, |
| 4219 | item_size, item_size + |
| 4220 | sizeof(struct btrfs_item), 1); |
Yan, Zheng | ad48fd75 | 2009-11-12 09:33:58 +0000 | [diff] [blame] | 4221 | leaf = path->nodes[0]; |
| 4222 | memcpy_extent_buffer(leaf, |
| 4223 | btrfs_item_ptr_offset(leaf, path->slots[0]), |
| 4224 | btrfs_item_ptr_offset(leaf, path->slots[0] - 1), |
| 4225 | item_size); |
| 4226 | return 0; |
| 4227 | } |
| 4228 | |
| 4229 | /* |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 4230 | * make the item pointed to by the path smaller. new_size indicates |
| 4231 | * how small to make it, and from_end tells us if we just chop bytes |
| 4232 | * off the end of the item or if we shift the item to chop bytes off |
| 4233 | * the front. |
| 4234 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4235 | void btrfs_truncate_item(struct btrfs_trans_handle *trans, |
| 4236 | struct btrfs_root *root, |
| 4237 | struct btrfs_path *path, |
| 4238 | u32 new_size, int from_end) |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4239 | { |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4240 | int slot; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4241 | struct extent_buffer *leaf; |
| 4242 | struct btrfs_item *item; |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4243 | u32 nritems; |
| 4244 | unsigned int data_end; |
| 4245 | unsigned int old_data_start; |
| 4246 | unsigned int old_size; |
| 4247 | unsigned int size_diff; |
| 4248 | int i; |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4249 | struct btrfs_map_token token; |
| 4250 | |
| 4251 | btrfs_init_map_token(&token); |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4252 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4253 | leaf = path->nodes[0]; |
Chris Mason | 179e29e | 2007-11-01 11:28:41 -0400 | [diff] [blame] | 4254 | slot = path->slots[0]; |
| 4255 | |
| 4256 | old_size = btrfs_item_size_nr(leaf, slot); |
| 4257 | if (old_size == new_size) |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4258 | return; |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4259 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4260 | nritems = btrfs_header_nritems(leaf); |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4261 | data_end = leaf_data_end(root, leaf); |
| 4262 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4263 | old_data_start = btrfs_item_offset_nr(leaf, slot); |
Chris Mason | 179e29e | 2007-11-01 11:28:41 -0400 | [diff] [blame] | 4264 | |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4265 | size_diff = old_size - new_size; |
| 4266 | |
| 4267 | BUG_ON(slot < 0); |
| 4268 | BUG_ON(slot >= nritems); |
| 4269 | |
| 4270 | /* |
| 4271 | * item0..itemN ... dataN.offset..dataN.size .. data0.size |
| 4272 | */ |
| 4273 | /* first correct the data pointers */ |
| 4274 | for (i = slot; i < nritems; i++) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4275 | u32 ioff; |
| 4276 | item = btrfs_item_nr(leaf, i); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 4277 | |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4278 | ioff = btrfs_token_item_offset(leaf, item, &token); |
| 4279 | btrfs_set_token_item_offset(leaf, item, |
| 4280 | ioff + size_diff, &token); |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4281 | } |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 4282 | |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4283 | /* shift the data */ |
Chris Mason | 179e29e | 2007-11-01 11:28:41 -0400 | [diff] [blame] | 4284 | if (from_end) { |
| 4285 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
| 4286 | data_end + size_diff, btrfs_leaf_data(leaf) + |
| 4287 | data_end, old_data_start + new_size - data_end); |
| 4288 | } else { |
| 4289 | struct btrfs_disk_key disk_key; |
| 4290 | u64 offset; |
| 4291 | |
| 4292 | btrfs_item_key(leaf, &disk_key, slot); |
| 4293 | |
| 4294 | if (btrfs_disk_key_type(&disk_key) == BTRFS_EXTENT_DATA_KEY) { |
| 4295 | unsigned long ptr; |
| 4296 | struct btrfs_file_extent_item *fi; |
| 4297 | |
| 4298 | fi = btrfs_item_ptr(leaf, slot, |
| 4299 | struct btrfs_file_extent_item); |
| 4300 | fi = (struct btrfs_file_extent_item *)( |
| 4301 | (unsigned long)fi - size_diff); |
| 4302 | |
| 4303 | if (btrfs_file_extent_type(leaf, fi) == |
| 4304 | BTRFS_FILE_EXTENT_INLINE) { |
| 4305 | ptr = btrfs_item_ptr_offset(leaf, slot); |
| 4306 | memmove_extent_buffer(leaf, ptr, |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 4307 | (unsigned long)fi, |
| 4308 | offsetof(struct btrfs_file_extent_item, |
Chris Mason | 179e29e | 2007-11-01 11:28:41 -0400 | [diff] [blame] | 4309 | disk_bytenr)); |
| 4310 | } |
| 4311 | } |
| 4312 | |
| 4313 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
| 4314 | data_end + size_diff, btrfs_leaf_data(leaf) + |
| 4315 | data_end, old_data_start - data_end); |
| 4316 | |
| 4317 | offset = btrfs_disk_key_offset(&disk_key); |
| 4318 | btrfs_set_disk_key_offset(&disk_key, offset + size_diff); |
| 4319 | btrfs_set_item_key(leaf, &disk_key, slot); |
| 4320 | if (slot == 0) |
| 4321 | fixup_low_keys(trans, root, path, &disk_key, 1); |
| 4322 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4323 | |
| 4324 | item = btrfs_item_nr(leaf, slot); |
| 4325 | btrfs_set_item_size(leaf, item, new_size); |
| 4326 | btrfs_mark_buffer_dirty(leaf); |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4327 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4328 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
| 4329 | btrfs_print_leaf(root, leaf); |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4330 | BUG(); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4331 | } |
Chris Mason | b18c668 | 2007-04-17 13:26:50 -0400 | [diff] [blame] | 4332 | } |
| 4333 | |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 4334 | /* |
| 4335 | * make the item pointed to by the path bigger, data_size is the new size. |
| 4336 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4337 | void btrfs_extend_item(struct btrfs_trans_handle *trans, |
| 4338 | struct btrfs_root *root, struct btrfs_path *path, |
| 4339 | u32 data_size) |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4340 | { |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4341 | int slot; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4342 | struct extent_buffer *leaf; |
| 4343 | struct btrfs_item *item; |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4344 | u32 nritems; |
| 4345 | unsigned int data_end; |
| 4346 | unsigned int old_data; |
| 4347 | unsigned int old_size; |
| 4348 | int i; |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4349 | struct btrfs_map_token token; |
| 4350 | |
| 4351 | btrfs_init_map_token(&token); |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4352 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4353 | leaf = path->nodes[0]; |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4354 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4355 | nritems = btrfs_header_nritems(leaf); |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4356 | data_end = leaf_data_end(root, leaf); |
| 4357 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4358 | if (btrfs_leaf_free_space(root, leaf) < data_size) { |
| 4359 | btrfs_print_leaf(root, leaf); |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4360 | BUG(); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4361 | } |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4362 | slot = path->slots[0]; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4363 | old_data = btrfs_item_end_nr(leaf, slot); |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4364 | |
| 4365 | BUG_ON(slot < 0); |
Chris Mason | 3326d1b | 2007-10-15 16:18:25 -0400 | [diff] [blame] | 4366 | if (slot >= nritems) { |
| 4367 | btrfs_print_leaf(root, leaf); |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 4368 | printk(KERN_CRIT "slot %d too large, nritems %d\n", |
| 4369 | slot, nritems); |
Chris Mason | 3326d1b | 2007-10-15 16:18:25 -0400 | [diff] [blame] | 4370 | BUG_ON(1); |
| 4371 | } |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4372 | |
| 4373 | /* |
| 4374 | * item0..itemN ... dataN.offset..dataN.size .. data0.size |
| 4375 | */ |
| 4376 | /* first correct the data pointers */ |
| 4377 | for (i = slot; i < nritems; i++) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4378 | u32 ioff; |
| 4379 | item = btrfs_item_nr(leaf, i); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 4380 | |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4381 | ioff = btrfs_token_item_offset(leaf, item, &token); |
| 4382 | btrfs_set_token_item_offset(leaf, item, |
| 4383 | ioff - data_size, &token); |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4384 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4385 | |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4386 | /* shift the data */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4387 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4388 | data_end - data_size, btrfs_leaf_data(leaf) + |
| 4389 | data_end, old_data - data_end); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4390 | |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4391 | data_end = old_data; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4392 | old_size = btrfs_item_size_nr(leaf, slot); |
| 4393 | item = btrfs_item_nr(leaf, slot); |
| 4394 | btrfs_set_item_size(leaf, item, old_size + data_size); |
| 4395 | btrfs_mark_buffer_dirty(leaf); |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4396 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4397 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
| 4398 | btrfs_print_leaf(root, leaf); |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4399 | BUG(); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4400 | } |
Chris Mason | 6567e83 | 2007-04-16 09:22:45 -0400 | [diff] [blame] | 4401 | } |
| 4402 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4403 | /* |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4404 | * this is a helper for btrfs_insert_empty_items, the main goal here is |
| 4405 | * to save stack depth by doing the bulk of the work in a function |
| 4406 | * that doesn't call btrfs_search_slot |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4407 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4408 | void setup_items_for_insert(struct btrfs_trans_handle *trans, |
| 4409 | struct btrfs_root *root, struct btrfs_path *path, |
| 4410 | struct btrfs_key *cpu_key, u32 *data_size, |
| 4411 | u32 total_data, u32 total_size, int nr) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4412 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4413 | struct btrfs_item *item; |
Chris Mason | 9c58309 | 2008-01-29 15:15:18 -0500 | [diff] [blame] | 4414 | int i; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 4415 | u32 nritems; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4416 | unsigned int data_end; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 4417 | struct btrfs_disk_key disk_key; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4418 | struct extent_buffer *leaf; |
| 4419 | int slot; |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4420 | struct btrfs_map_token token; |
| 4421 | |
| 4422 | btrfs_init_map_token(&token); |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 4423 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4424 | leaf = path->nodes[0]; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4425 | slot = path->slots[0]; |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4426 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4427 | nritems = btrfs_header_nritems(leaf); |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 4428 | data_end = leaf_data_end(root, leaf); |
Chris Mason | eb60cea | 2007-02-02 09:18:22 -0500 | [diff] [blame] | 4429 | |
Chris Mason | f25956c | 2008-09-12 15:32:53 -0400 | [diff] [blame] | 4430 | if (btrfs_leaf_free_space(root, leaf) < total_size) { |
Chris Mason | 3326d1b | 2007-10-15 16:18:25 -0400 | [diff] [blame] | 4431 | btrfs_print_leaf(root, leaf); |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 4432 | printk(KERN_CRIT "not enough freespace need %u have %d\n", |
Chris Mason | 9c58309 | 2008-01-29 15:15:18 -0500 | [diff] [blame] | 4433 | total_size, btrfs_leaf_free_space(root, leaf)); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4434 | BUG(); |
Chris Mason | d4dbff9 | 2007-04-04 14:08:15 -0400 | [diff] [blame] | 4435 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4436 | |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4437 | if (slot != nritems) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4438 | unsigned int old_data = btrfs_item_end_nr(leaf, slot); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4439 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4440 | if (old_data < data_end) { |
| 4441 | btrfs_print_leaf(root, leaf); |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 4442 | printk(KERN_CRIT "slot %d old_data %d data_end %d\n", |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4443 | slot, old_data, data_end); |
| 4444 | BUG_ON(1); |
| 4445 | } |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4446 | /* |
| 4447 | * item0..itemN ... dataN.offset..dataN.size .. data0.size |
| 4448 | */ |
| 4449 | /* first correct the data pointers */ |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 4450 | for (i = slot; i < nritems; i++) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4451 | u32 ioff; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 4452 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4453 | item = btrfs_item_nr(leaf, i); |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4454 | ioff = btrfs_token_item_offset(leaf, item, &token); |
| 4455 | btrfs_set_token_item_offset(leaf, item, |
| 4456 | ioff - total_data, &token); |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 4457 | } |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4458 | /* shift the items */ |
Chris Mason | 9c58309 | 2008-01-29 15:15:18 -0500 | [diff] [blame] | 4459 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr), |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4460 | btrfs_item_nr_offset(slot), |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 4461 | (nritems - slot) * sizeof(struct btrfs_item)); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4462 | |
| 4463 | /* shift the data */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4464 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
Chris Mason | 9c58309 | 2008-01-29 15:15:18 -0500 | [diff] [blame] | 4465 | data_end - total_data, btrfs_leaf_data(leaf) + |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 4466 | data_end, old_data - data_end); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4467 | data_end = old_data; |
| 4468 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4469 | |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 4470 | /* setup the item for the new data */ |
Chris Mason | 9c58309 | 2008-01-29 15:15:18 -0500 | [diff] [blame] | 4471 | for (i = 0; i < nr; i++) { |
| 4472 | btrfs_cpu_key_to_disk(&disk_key, cpu_key + i); |
| 4473 | btrfs_set_item_key(leaf, &disk_key, slot + i); |
| 4474 | item = btrfs_item_nr(leaf, slot + i); |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4475 | btrfs_set_token_item_offset(leaf, item, |
| 4476 | data_end - data_size[i], &token); |
Chris Mason | 9c58309 | 2008-01-29 15:15:18 -0500 | [diff] [blame] | 4477 | data_end -= data_size[i]; |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4478 | btrfs_set_token_item_size(leaf, item, data_size[i], &token); |
Chris Mason | 9c58309 | 2008-01-29 15:15:18 -0500 | [diff] [blame] | 4479 | } |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4480 | |
Chris Mason | 9c58309 | 2008-01-29 15:15:18 -0500 | [diff] [blame] | 4481 | btrfs_set_header_nritems(leaf, nritems + nr); |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4482 | |
Chris Mason | 5a01a2e | 2008-01-30 11:43:54 -0500 | [diff] [blame] | 4483 | if (slot == 0) { |
| 4484 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4485 | fixup_low_keys(trans, root, path, &disk_key, 1); |
Chris Mason | 5a01a2e | 2008-01-30 11:43:54 -0500 | [diff] [blame] | 4486 | } |
Chris Mason | b947343 | 2009-03-13 11:00:37 -0400 | [diff] [blame] | 4487 | btrfs_unlock_up_safe(path, 1); |
| 4488 | btrfs_mark_buffer_dirty(leaf); |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4489 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4490 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
| 4491 | btrfs_print_leaf(root, leaf); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4492 | BUG(); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4493 | } |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4494 | } |
| 4495 | |
| 4496 | /* |
| 4497 | * Given a key and some data, insert items into the tree. |
| 4498 | * This does all the path init required, making room in the tree if needed. |
| 4499 | */ |
| 4500 | int btrfs_insert_empty_items(struct btrfs_trans_handle *trans, |
| 4501 | struct btrfs_root *root, |
| 4502 | struct btrfs_path *path, |
| 4503 | struct btrfs_key *cpu_key, u32 *data_size, |
| 4504 | int nr) |
| 4505 | { |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4506 | int ret = 0; |
| 4507 | int slot; |
| 4508 | int i; |
| 4509 | u32 total_size = 0; |
| 4510 | u32 total_data = 0; |
| 4511 | |
| 4512 | for (i = 0; i < nr; i++) |
| 4513 | total_data += data_size[i]; |
| 4514 | |
| 4515 | total_size = total_data + (nr * sizeof(struct btrfs_item)); |
| 4516 | ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1); |
| 4517 | if (ret == 0) |
| 4518 | return -EEXIST; |
| 4519 | if (ret < 0) |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4520 | return ret; |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4521 | |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4522 | slot = path->slots[0]; |
| 4523 | BUG_ON(slot < 0); |
| 4524 | |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4525 | setup_items_for_insert(trans, root, path, cpu_key, data_size, |
Chris Mason | 44871b1 | 2009-03-13 10:04:31 -0400 | [diff] [blame] | 4526 | total_data, total_size, nr); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4527 | return 0; |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 4528 | } |
| 4529 | |
| 4530 | /* |
| 4531 | * Given a key and some data, insert an item into the tree. |
| 4532 | * This does all the path init required, making room in the tree if needed. |
| 4533 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame] | 4534 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
| 4535 | *root, struct btrfs_key *cpu_key, void *data, u32 |
| 4536 | data_size) |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 4537 | { |
| 4538 | int ret = 0; |
Chris Mason | 2c90e5d | 2007-04-02 10:50:19 -0400 | [diff] [blame] | 4539 | struct btrfs_path *path; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4540 | struct extent_buffer *leaf; |
| 4541 | unsigned long ptr; |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 4542 | |
Chris Mason | 2c90e5d | 2007-04-02 10:50:19 -0400 | [diff] [blame] | 4543 | path = btrfs_alloc_path(); |
Tsutomu Itoh | db5b493 | 2011-03-23 08:14:16 +0000 | [diff] [blame] | 4544 | if (!path) |
| 4545 | return -ENOMEM; |
Chris Mason | 2c90e5d | 2007-04-02 10:50:19 -0400 | [diff] [blame] | 4546 | ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 4547 | if (!ret) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4548 | leaf = path->nodes[0]; |
| 4549 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); |
| 4550 | write_extent_buffer(leaf, data, ptr, data_size); |
| 4551 | btrfs_mark_buffer_dirty(leaf); |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 4552 | } |
Chris Mason | 2c90e5d | 2007-04-02 10:50:19 -0400 | [diff] [blame] | 4553 | btrfs_free_path(path); |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4554 | return ret; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4555 | } |
| 4556 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4557 | /* |
Chris Mason | 5de08d7 | 2007-02-24 06:24:44 -0500 | [diff] [blame] | 4558 | * delete the pointer from a given node. |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4559 | * |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 4560 | * the tree should have been previously balanced so the deletion does not |
| 4561 | * empty a node. |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4562 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4563 | static void del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 4564 | struct btrfs_path *path, int level, int slot, |
| 4565 | int tree_mod_log) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4566 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4567 | struct extent_buffer *parent = path->nodes[level]; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 4568 | u32 nritems; |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 4569 | int ret; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4570 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4571 | nritems = btrfs_header_nritems(parent); |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 4572 | if (slot != nritems - 1) { |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 4573 | if (tree_mod_log && level) |
| 4574 | tree_mod_log_eb_move(root->fs_info, parent, slot, |
| 4575 | slot + 1, nritems - slot - 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4576 | memmove_extent_buffer(parent, |
| 4577 | btrfs_node_key_ptr_offset(slot), |
| 4578 | btrfs_node_key_ptr_offset(slot + 1), |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 4579 | sizeof(struct btrfs_key_ptr) * |
| 4580 | (nritems - slot - 1)); |
Jan Schmidt | f395694 | 2012-05-31 15:02:32 +0200 | [diff] [blame] | 4581 | } else if (tree_mod_log && level) { |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 4582 | ret = tree_mod_log_insert_key(root->fs_info, parent, slot, |
| 4583 | MOD_LOG_KEY_REMOVE); |
| 4584 | BUG_ON(ret < 0); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 4585 | } |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 4586 | |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 4587 | nritems--; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4588 | btrfs_set_header_nritems(parent, nritems); |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 4589 | if (nritems == 0 && parent == root->node) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4590 | BUG_ON(btrfs_header_level(root->node) != 1); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 4591 | /* just turn the root into a leaf and break */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4592 | btrfs_set_header_level(root->node, 0); |
Chris Mason | bb80395 | 2007-03-01 12:04:21 -0500 | [diff] [blame] | 4593 | } else if (slot == 0) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4594 | struct btrfs_disk_key disk_key; |
| 4595 | |
| 4596 | btrfs_node_key(parent, &disk_key, 0); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4597 | fixup_low_keys(trans, root, path, &disk_key, level + 1); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4598 | } |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 4599 | btrfs_mark_buffer_dirty(parent); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4600 | } |
| 4601 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4602 | /* |
Chris Mason | 323ac95 | 2008-10-01 19:05:46 -0400 | [diff] [blame] | 4603 | * a helper function to delete the leaf pointed to by path->slots[1] and |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 4604 | * path->nodes[1]. |
Chris Mason | 323ac95 | 2008-10-01 19:05:46 -0400 | [diff] [blame] | 4605 | * |
| 4606 | * This deletes the pointer in path->nodes[1] and frees the leaf |
| 4607 | * block extent. zero is returned if it all worked out, < 0 otherwise. |
| 4608 | * |
| 4609 | * The path must have already been setup for deleting the leaf, including |
| 4610 | * all the proper balancing. path->nodes[1] must be locked. |
| 4611 | */ |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4612 | static noinline void btrfs_del_leaf(struct btrfs_trans_handle *trans, |
| 4613 | struct btrfs_root *root, |
| 4614 | struct btrfs_path *path, |
| 4615 | struct extent_buffer *leaf) |
Chris Mason | 323ac95 | 2008-10-01 19:05:46 -0400 | [diff] [blame] | 4616 | { |
Yan Zheng | 5d4f98a | 2009-06-10 10:45:14 -0400 | [diff] [blame] | 4617 | WARN_ON(btrfs_header_generation(leaf) != trans->transid); |
Jan Schmidt | f3ea38d | 2012-05-26 11:45:21 +0200 | [diff] [blame] | 4618 | del_ptr(trans, root, path, 1, path->slots[1], 1); |
Chris Mason | 323ac95 | 2008-10-01 19:05:46 -0400 | [diff] [blame] | 4619 | |
Chris Mason | 4d081c4 | 2009-02-04 09:31:28 -0500 | [diff] [blame] | 4620 | /* |
| 4621 | * btrfs_free_extent is expensive, we want to make sure we |
| 4622 | * aren't holding any locks when we call it |
| 4623 | */ |
| 4624 | btrfs_unlock_up_safe(path, 0); |
| 4625 | |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 4626 | root_sub_used(root, leaf->len); |
| 4627 | |
Josef Bacik | 3083ee2 | 2012-03-09 16:01:49 -0500 | [diff] [blame] | 4628 | extent_buffer_get(leaf); |
Jan Schmidt | 5581a51 | 2012-05-16 17:04:52 +0200 | [diff] [blame] | 4629 | btrfs_free_tree_block(trans, root, leaf, 0, 1); |
Josef Bacik | 3083ee2 | 2012-03-09 16:01:49 -0500 | [diff] [blame] | 4630 | free_extent_buffer_stale(leaf); |
Chris Mason | 323ac95 | 2008-10-01 19:05:46 -0400 | [diff] [blame] | 4631 | } |
| 4632 | /* |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4633 | * delete the item at the leaf level in path. If that empties |
| 4634 | * the leaf, remove it from the tree |
| 4635 | */ |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4636 | int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
| 4637 | struct btrfs_path *path, int slot, int nr) |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4638 | { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4639 | struct extent_buffer *leaf; |
| 4640 | struct btrfs_item *item; |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4641 | int last_off; |
| 4642 | int dsize = 0; |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4643 | int ret = 0; |
| 4644 | int wret; |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4645 | int i; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 4646 | u32 nritems; |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4647 | struct btrfs_map_token token; |
| 4648 | |
| 4649 | btrfs_init_map_token(&token); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4650 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4651 | leaf = path->nodes[0]; |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4652 | last_off = btrfs_item_offset_nr(leaf, slot + nr - 1); |
| 4653 | |
| 4654 | for (i = 0; i < nr; i++) |
| 4655 | dsize += btrfs_item_size_nr(leaf, slot + i); |
| 4656 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4657 | nritems = btrfs_header_nritems(leaf); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4658 | |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4659 | if (slot + nr != nritems) { |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 4660 | int data_end = leaf_data_end(root, leaf); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4661 | |
| 4662 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 4663 | data_end + dsize, |
| 4664 | btrfs_leaf_data(leaf) + data_end, |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4665 | last_off - data_end); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4666 | |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4667 | for (i = slot + nr; i < nritems; i++) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4668 | u32 ioff; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 4669 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4670 | item = btrfs_item_nr(leaf, i); |
Chris Mason | cfed81a | 2012-03-03 07:40:03 -0500 | [diff] [blame] | 4671 | ioff = btrfs_token_item_offset(leaf, item, &token); |
| 4672 | btrfs_set_token_item_offset(leaf, item, |
| 4673 | ioff + dsize, &token); |
Chris Mason | 0783fcf | 2007-03-12 20:12:07 -0400 | [diff] [blame] | 4674 | } |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 4675 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4676 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot), |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4677 | btrfs_item_nr_offset(slot + nr), |
Chris Mason | d602557 | 2007-03-30 14:27:56 -0400 | [diff] [blame] | 4678 | sizeof(struct btrfs_item) * |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4679 | (nritems - slot - nr)); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4680 | } |
Chris Mason | 85e21ba | 2008-01-29 15:11:36 -0500 | [diff] [blame] | 4681 | btrfs_set_header_nritems(leaf, nritems - nr); |
| 4682 | nritems -= nr; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4683 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4684 | /* delete the leaf if we've emptied it */ |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 4685 | if (nritems == 0) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4686 | if (leaf == root->node) { |
| 4687 | btrfs_set_header_level(leaf, 0); |
Chris Mason | 9a8dd15 | 2007-02-23 08:38:36 -0500 | [diff] [blame] | 4688 | } else { |
Yan, Zheng | f0486c6 | 2010-05-16 10:46:25 -0400 | [diff] [blame] | 4689 | btrfs_set_path_blocking(path); |
| 4690 | clean_tree_block(trans, root, leaf); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4691 | btrfs_del_leaf(trans, root, path, leaf); |
Chris Mason | 9a8dd15 | 2007-02-23 08:38:36 -0500 | [diff] [blame] | 4692 | } |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4693 | } else { |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 4694 | int used = leaf_space_used(leaf, 0, nritems); |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4695 | if (slot == 0) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4696 | struct btrfs_disk_key disk_key; |
| 4697 | |
| 4698 | btrfs_item_key(leaf, &disk_key, 0); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4699 | fixup_low_keys(trans, root, path, &disk_key, 1); |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4700 | } |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4701 | |
Chris Mason | 74123bd | 2007-02-02 11:05:29 -0500 | [diff] [blame] | 4702 | /* delete the leaf if it is mostly empty */ |
Yan Zheng | d717aa1 | 2009-07-24 12:42:46 -0400 | [diff] [blame] | 4703 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4704 | /* push_leaf_left fixes the path. |
| 4705 | * make sure the path still points to our leaf |
| 4706 | * for possible call to del_ptr below |
| 4707 | */ |
Chris Mason | 4920c9a | 2007-01-26 16:38:42 -0500 | [diff] [blame] | 4708 | slot = path->slots[1]; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4709 | extent_buffer_get(leaf); |
| 4710 | |
Chris Mason | b947343 | 2009-03-13 11:00:37 -0400 | [diff] [blame] | 4711 | btrfs_set_path_blocking(path); |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 4712 | wret = push_leaf_left(trans, root, path, 1, 1, |
| 4713 | 1, (u32)-1); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 4714 | if (wret < 0 && wret != -ENOSPC) |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4715 | ret = wret; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4716 | |
| 4717 | if (path->nodes[0] == leaf && |
| 4718 | btrfs_header_nritems(leaf)) { |
Chris Mason | 99d8f83 | 2010-07-07 10:51:48 -0400 | [diff] [blame] | 4719 | wret = push_leaf_right(trans, root, path, 1, |
| 4720 | 1, 1, 0); |
Chris Mason | 54aa1f4 | 2007-06-22 14:16:25 -0400 | [diff] [blame] | 4721 | if (wret < 0 && wret != -ENOSPC) |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4722 | ret = wret; |
| 4723 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4724 | |
| 4725 | if (btrfs_header_nritems(leaf) == 0) { |
Chris Mason | 323ac95 | 2008-10-01 19:05:46 -0400 | [diff] [blame] | 4726 | path->slots[1] = slot; |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4727 | btrfs_del_leaf(trans, root, path, leaf); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4728 | free_extent_buffer(leaf); |
Jeff Mahoney | 143bede | 2012-03-01 14:56:26 +0100 | [diff] [blame] | 4729 | ret = 0; |
Chris Mason | 5de08d7 | 2007-02-24 06:24:44 -0500 | [diff] [blame] | 4730 | } else { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 4731 | /* if we're still in the path, make sure |
| 4732 | * we're dirty. Otherwise, one of the |
| 4733 | * push_leaf functions must have already |
| 4734 | * dirtied this buffer |
| 4735 | */ |
| 4736 | if (path->nodes[0] == leaf) |
| 4737 | btrfs_mark_buffer_dirty(leaf); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4738 | free_extent_buffer(leaf); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4739 | } |
Chris Mason | d571976 | 2007-03-23 10:01:08 -0400 | [diff] [blame] | 4740 | } else { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 4741 | btrfs_mark_buffer_dirty(leaf); |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4742 | } |
| 4743 | } |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 4744 | return ret; |
Chris Mason | be0e5c0 | 2007-01-26 15:51:26 -0500 | [diff] [blame] | 4745 | } |
| 4746 | |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 4747 | /* |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 4748 | * search the tree again to find a leaf with lesser keys |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 4749 | * returns 0 if it found something or 1 if there are no lesser leaves. |
| 4750 | * returns < 0 on io errors. |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 4751 | * |
| 4752 | * This may release the path, and so you may lose any locks held at the |
| 4753 | * time you call it. |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 4754 | */ |
| 4755 | int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path) |
| 4756 | { |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 4757 | struct btrfs_key key; |
| 4758 | struct btrfs_disk_key found_key; |
| 4759 | int ret; |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 4760 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 4761 | btrfs_item_key_to_cpu(path->nodes[0], &key, 0); |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 4762 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 4763 | if (key.offset > 0) |
| 4764 | key.offset--; |
| 4765 | else if (key.type > 0) |
| 4766 | key.type--; |
| 4767 | else if (key.objectid > 0) |
| 4768 | key.objectid--; |
| 4769 | else |
| 4770 | return 1; |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 4771 | |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 4772 | btrfs_release_path(path); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 4773 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 4774 | if (ret < 0) |
| 4775 | return ret; |
| 4776 | btrfs_item_key(path->nodes[0], &found_key, 0); |
| 4777 | ret = comp_keys(&found_key, &key); |
| 4778 | if (ret < 0) |
| 4779 | return 0; |
| 4780 | return 1; |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 4781 | } |
| 4782 | |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4783 | /* |
| 4784 | * A helper function to walk down the tree starting at min_key, and looking |
| 4785 | * for nodes or leaves that are either in cache or have a minimum |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 4786 | * transaction id. This is used by the btree defrag code, and tree logging |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4787 | * |
| 4788 | * This does not cow, but it does stuff the starting key it finds back |
| 4789 | * into min_key, so you can call btrfs_search_slot with cow=1 on the |
| 4790 | * key and get a writable path. |
| 4791 | * |
| 4792 | * This does lock as it descends, and path->keep_locks should be set |
| 4793 | * to 1 by the caller. |
| 4794 | * |
| 4795 | * This honors path->lowest_level to prevent descent past a given level |
| 4796 | * of the tree. |
| 4797 | * |
Chris Mason | d352ac6 | 2008-09-29 15:18:18 -0400 | [diff] [blame] | 4798 | * min_trans indicates the oldest transaction that you are interested |
| 4799 | * in walking through. Any nodes or leaves older than min_trans are |
| 4800 | * skipped over (without reading them). |
| 4801 | * |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4802 | * returns zero if something useful was found, < 0 on error and 1 if there |
| 4803 | * was nothing in the tree that matched the search criteria. |
| 4804 | */ |
| 4805 | int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4806 | struct btrfs_key *max_key, |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4807 | struct btrfs_path *path, int cache_only, |
| 4808 | u64 min_trans) |
| 4809 | { |
| 4810 | struct extent_buffer *cur; |
| 4811 | struct btrfs_key found_key; |
| 4812 | int slot; |
Yan | 9652480 | 2008-07-24 12:19:49 -0400 | [diff] [blame] | 4813 | int sret; |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4814 | u32 nritems; |
| 4815 | int level; |
| 4816 | int ret = 1; |
| 4817 | |
Chris Mason | 934d375 | 2008-12-08 16:43:10 -0500 | [diff] [blame] | 4818 | WARN_ON(!path->keep_locks); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4819 | again: |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 4820 | cur = btrfs_read_lock_root_node(root); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4821 | level = btrfs_header_level(cur); |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4822 | WARN_ON(path->nodes[level]); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4823 | path->nodes[level] = cur; |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 4824 | path->locks[level] = BTRFS_READ_LOCK; |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4825 | |
| 4826 | if (btrfs_header_generation(cur) < min_trans) { |
| 4827 | ret = 1; |
| 4828 | goto out; |
| 4829 | } |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 4830 | while (1) { |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4831 | nritems = btrfs_header_nritems(cur); |
| 4832 | level = btrfs_header_level(cur); |
Yan | 9652480 | 2008-07-24 12:19:49 -0400 | [diff] [blame] | 4833 | sret = bin_search(cur, min_key, level, &slot); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4834 | |
Chris Mason | 323ac95 | 2008-10-01 19:05:46 -0400 | [diff] [blame] | 4835 | /* at the lowest level, we're done, setup the path and exit */ |
| 4836 | if (level == path->lowest_level) { |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4837 | if (slot >= nritems) |
| 4838 | goto find_next_key; |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4839 | ret = 0; |
| 4840 | path->slots[level] = slot; |
| 4841 | btrfs_item_key_to_cpu(cur, &found_key, slot); |
| 4842 | goto out; |
| 4843 | } |
Yan | 9652480 | 2008-07-24 12:19:49 -0400 | [diff] [blame] | 4844 | if (sret && slot > 0) |
| 4845 | slot--; |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4846 | /* |
| 4847 | * check this node pointer against the cache_only and |
| 4848 | * min_trans parameters. If it isn't in cache or is too |
| 4849 | * old, skip to the next one. |
| 4850 | */ |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 4851 | while (slot < nritems) { |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4852 | u64 blockptr; |
| 4853 | u64 gen; |
| 4854 | struct extent_buffer *tmp; |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4855 | struct btrfs_disk_key disk_key; |
| 4856 | |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4857 | blockptr = btrfs_node_blockptr(cur, slot); |
| 4858 | gen = btrfs_node_ptr_generation(cur, slot); |
| 4859 | if (gen < min_trans) { |
| 4860 | slot++; |
| 4861 | continue; |
| 4862 | } |
| 4863 | if (!cache_only) |
| 4864 | break; |
| 4865 | |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4866 | if (max_key) { |
| 4867 | btrfs_node_key(cur, &disk_key, slot); |
| 4868 | if (comp_keys(&disk_key, max_key) >= 0) { |
| 4869 | ret = 1; |
| 4870 | goto out; |
| 4871 | } |
| 4872 | } |
| 4873 | |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4874 | tmp = btrfs_find_tree_block(root, blockptr, |
| 4875 | btrfs_level_size(root, level - 1)); |
| 4876 | |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 4877 | if (tmp && btrfs_buffer_uptodate(tmp, gen, 1) > 0) { |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4878 | free_extent_buffer(tmp); |
| 4879 | break; |
| 4880 | } |
| 4881 | if (tmp) |
| 4882 | free_extent_buffer(tmp); |
| 4883 | slot++; |
| 4884 | } |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4885 | find_next_key: |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4886 | /* |
| 4887 | * we didn't find a candidate key in this node, walk forward |
| 4888 | * and find another one |
| 4889 | */ |
| 4890 | if (slot >= nritems) { |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4891 | path->slots[level] = slot; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 4892 | btrfs_set_path_blocking(path); |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4893 | sret = btrfs_find_next_key(root, path, min_key, level, |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4894 | cache_only, min_trans); |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 4895 | if (sret == 0) { |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 4896 | btrfs_release_path(path); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4897 | goto again; |
| 4898 | } else { |
| 4899 | goto out; |
| 4900 | } |
| 4901 | } |
| 4902 | /* save our key for returning back */ |
| 4903 | btrfs_node_key_to_cpu(cur, &found_key, slot); |
| 4904 | path->slots[level] = slot; |
| 4905 | if (level == path->lowest_level) { |
| 4906 | ret = 0; |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 4907 | unlock_up(path, level, 1, 0, NULL); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4908 | goto out; |
| 4909 | } |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 4910 | btrfs_set_path_blocking(path); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4911 | cur = read_node_slot(root, cur, slot); |
Jeff Mahoney | 79787ea | 2012-03-12 16:03:00 +0100 | [diff] [blame] | 4912 | BUG_ON(!cur); /* -ENOMEM */ |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4913 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 4914 | btrfs_tree_read_lock(cur); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 4915 | |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 4916 | path->locks[level - 1] = BTRFS_READ_LOCK; |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4917 | path->nodes[level - 1] = cur; |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 4918 | unlock_up(path, level, 1, 0, NULL); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 4919 | btrfs_clear_path_blocking(path, NULL, 0); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4920 | } |
| 4921 | out: |
| 4922 | if (ret == 0) |
| 4923 | memcpy(min_key, &found_key, sizeof(found_key)); |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 4924 | btrfs_set_path_blocking(path); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 4925 | return ret; |
| 4926 | } |
| 4927 | |
Alexander Block | 7069830 | 2012-06-05 21:07:48 +0200 | [diff] [blame] | 4928 | static void tree_move_down(struct btrfs_root *root, |
| 4929 | struct btrfs_path *path, |
| 4930 | int *level, int root_level) |
| 4931 | { |
Chris Mason | 74dd17f | 2012-08-07 16:25:13 -0400 | [diff] [blame] | 4932 | BUG_ON(*level == 0); |
Alexander Block | 7069830 | 2012-06-05 21:07:48 +0200 | [diff] [blame] | 4933 | path->nodes[*level - 1] = read_node_slot(root, path->nodes[*level], |
| 4934 | path->slots[*level]); |
| 4935 | path->slots[*level - 1] = 0; |
| 4936 | (*level)--; |
| 4937 | } |
| 4938 | |
| 4939 | static int tree_move_next_or_upnext(struct btrfs_root *root, |
| 4940 | struct btrfs_path *path, |
| 4941 | int *level, int root_level) |
| 4942 | { |
| 4943 | int ret = 0; |
| 4944 | int nritems; |
| 4945 | nritems = btrfs_header_nritems(path->nodes[*level]); |
| 4946 | |
| 4947 | path->slots[*level]++; |
| 4948 | |
Chris Mason | 74dd17f | 2012-08-07 16:25:13 -0400 | [diff] [blame] | 4949 | while (path->slots[*level] >= nritems) { |
Alexander Block | 7069830 | 2012-06-05 21:07:48 +0200 | [diff] [blame] | 4950 | if (*level == root_level) |
| 4951 | return -1; |
| 4952 | |
| 4953 | /* move upnext */ |
| 4954 | path->slots[*level] = 0; |
| 4955 | free_extent_buffer(path->nodes[*level]); |
| 4956 | path->nodes[*level] = NULL; |
| 4957 | (*level)++; |
| 4958 | path->slots[*level]++; |
| 4959 | |
| 4960 | nritems = btrfs_header_nritems(path->nodes[*level]); |
| 4961 | ret = 1; |
| 4962 | } |
| 4963 | return ret; |
| 4964 | } |
| 4965 | |
| 4966 | /* |
| 4967 | * Returns 1 if it had to move up and next. 0 is returned if it moved only next |
| 4968 | * or down. |
| 4969 | */ |
| 4970 | static int tree_advance(struct btrfs_root *root, |
| 4971 | struct btrfs_path *path, |
| 4972 | int *level, int root_level, |
| 4973 | int allow_down, |
| 4974 | struct btrfs_key *key) |
| 4975 | { |
| 4976 | int ret; |
| 4977 | |
| 4978 | if (*level == 0 || !allow_down) { |
| 4979 | ret = tree_move_next_or_upnext(root, path, level, root_level); |
| 4980 | } else { |
| 4981 | tree_move_down(root, path, level, root_level); |
| 4982 | ret = 0; |
| 4983 | } |
| 4984 | if (ret >= 0) { |
| 4985 | if (*level == 0) |
| 4986 | btrfs_item_key_to_cpu(path->nodes[*level], key, |
| 4987 | path->slots[*level]); |
| 4988 | else |
| 4989 | btrfs_node_key_to_cpu(path->nodes[*level], key, |
| 4990 | path->slots[*level]); |
| 4991 | } |
| 4992 | return ret; |
| 4993 | } |
| 4994 | |
| 4995 | static int tree_compare_item(struct btrfs_root *left_root, |
| 4996 | struct btrfs_path *left_path, |
| 4997 | struct btrfs_path *right_path, |
| 4998 | char *tmp_buf) |
| 4999 | { |
| 5000 | int cmp; |
| 5001 | int len1, len2; |
| 5002 | unsigned long off1, off2; |
| 5003 | |
| 5004 | len1 = btrfs_item_size_nr(left_path->nodes[0], left_path->slots[0]); |
| 5005 | len2 = btrfs_item_size_nr(right_path->nodes[0], right_path->slots[0]); |
| 5006 | if (len1 != len2) |
| 5007 | return 1; |
| 5008 | |
| 5009 | off1 = btrfs_item_ptr_offset(left_path->nodes[0], left_path->slots[0]); |
| 5010 | off2 = btrfs_item_ptr_offset(right_path->nodes[0], |
| 5011 | right_path->slots[0]); |
| 5012 | |
| 5013 | read_extent_buffer(left_path->nodes[0], tmp_buf, off1, len1); |
| 5014 | |
| 5015 | cmp = memcmp_extent_buffer(right_path->nodes[0], tmp_buf, off2, len1); |
| 5016 | if (cmp) |
| 5017 | return 1; |
| 5018 | return 0; |
| 5019 | } |
| 5020 | |
| 5021 | #define ADVANCE 1 |
| 5022 | #define ADVANCE_ONLY_NEXT -1 |
| 5023 | |
| 5024 | /* |
| 5025 | * This function compares two trees and calls the provided callback for |
| 5026 | * every changed/new/deleted item it finds. |
| 5027 | * If shared tree blocks are encountered, whole subtrees are skipped, making |
| 5028 | * the compare pretty fast on snapshotted subvolumes. |
| 5029 | * |
| 5030 | * This currently works on commit roots only. As commit roots are read only, |
| 5031 | * we don't do any locking. The commit roots are protected with transactions. |
| 5032 | * Transactions are ended and rejoined when a commit is tried in between. |
| 5033 | * |
| 5034 | * This function checks for modifications done to the trees while comparing. |
| 5035 | * If it detects a change, it aborts immediately. |
| 5036 | */ |
| 5037 | int btrfs_compare_trees(struct btrfs_root *left_root, |
| 5038 | struct btrfs_root *right_root, |
| 5039 | btrfs_changed_cb_t changed_cb, void *ctx) |
| 5040 | { |
| 5041 | int ret; |
| 5042 | int cmp; |
| 5043 | struct btrfs_trans_handle *trans = NULL; |
| 5044 | struct btrfs_path *left_path = NULL; |
| 5045 | struct btrfs_path *right_path = NULL; |
| 5046 | struct btrfs_key left_key; |
| 5047 | struct btrfs_key right_key; |
| 5048 | char *tmp_buf = NULL; |
| 5049 | int left_root_level; |
| 5050 | int right_root_level; |
| 5051 | int left_level; |
| 5052 | int right_level; |
| 5053 | int left_end_reached; |
| 5054 | int right_end_reached; |
| 5055 | int advance_left; |
| 5056 | int advance_right; |
| 5057 | u64 left_blockptr; |
| 5058 | u64 right_blockptr; |
| 5059 | u64 left_start_ctransid; |
| 5060 | u64 right_start_ctransid; |
| 5061 | u64 ctransid; |
| 5062 | |
| 5063 | left_path = btrfs_alloc_path(); |
| 5064 | if (!left_path) { |
| 5065 | ret = -ENOMEM; |
| 5066 | goto out; |
| 5067 | } |
| 5068 | right_path = btrfs_alloc_path(); |
| 5069 | if (!right_path) { |
| 5070 | ret = -ENOMEM; |
| 5071 | goto out; |
| 5072 | } |
| 5073 | |
| 5074 | tmp_buf = kmalloc(left_root->leafsize, GFP_NOFS); |
| 5075 | if (!tmp_buf) { |
| 5076 | ret = -ENOMEM; |
| 5077 | goto out; |
| 5078 | } |
| 5079 | |
| 5080 | left_path->search_commit_root = 1; |
| 5081 | left_path->skip_locking = 1; |
| 5082 | right_path->search_commit_root = 1; |
| 5083 | right_path->skip_locking = 1; |
| 5084 | |
| 5085 | spin_lock(&left_root->root_times_lock); |
| 5086 | left_start_ctransid = btrfs_root_ctransid(&left_root->root_item); |
| 5087 | spin_unlock(&left_root->root_times_lock); |
| 5088 | |
| 5089 | spin_lock(&right_root->root_times_lock); |
| 5090 | right_start_ctransid = btrfs_root_ctransid(&right_root->root_item); |
| 5091 | spin_unlock(&right_root->root_times_lock); |
| 5092 | |
| 5093 | trans = btrfs_join_transaction(left_root); |
| 5094 | if (IS_ERR(trans)) { |
| 5095 | ret = PTR_ERR(trans); |
| 5096 | trans = NULL; |
| 5097 | goto out; |
| 5098 | } |
| 5099 | |
| 5100 | /* |
| 5101 | * Strategy: Go to the first items of both trees. Then do |
| 5102 | * |
| 5103 | * If both trees are at level 0 |
| 5104 | * Compare keys of current items |
| 5105 | * If left < right treat left item as new, advance left tree |
| 5106 | * and repeat |
| 5107 | * If left > right treat right item as deleted, advance right tree |
| 5108 | * and repeat |
| 5109 | * If left == right do deep compare of items, treat as changed if |
| 5110 | * needed, advance both trees and repeat |
| 5111 | * If both trees are at the same level but not at level 0 |
| 5112 | * Compare keys of current nodes/leafs |
| 5113 | * If left < right advance left tree and repeat |
| 5114 | * If left > right advance right tree and repeat |
| 5115 | * If left == right compare blockptrs of the next nodes/leafs |
| 5116 | * If they match advance both trees but stay at the same level |
| 5117 | * and repeat |
| 5118 | * If they don't match advance both trees while allowing to go |
| 5119 | * deeper and repeat |
| 5120 | * If tree levels are different |
| 5121 | * Advance the tree that needs it and repeat |
| 5122 | * |
| 5123 | * Advancing a tree means: |
| 5124 | * If we are at level 0, try to go to the next slot. If that's not |
| 5125 | * possible, go one level up and repeat. Stop when we found a level |
| 5126 | * where we could go to the next slot. We may at this point be on a |
| 5127 | * node or a leaf. |
| 5128 | * |
| 5129 | * If we are not at level 0 and not on shared tree blocks, go one |
| 5130 | * level deeper. |
| 5131 | * |
| 5132 | * If we are not at level 0 and on shared tree blocks, go one slot to |
| 5133 | * the right if possible or go up and right. |
| 5134 | */ |
| 5135 | |
| 5136 | left_level = btrfs_header_level(left_root->commit_root); |
| 5137 | left_root_level = left_level; |
| 5138 | left_path->nodes[left_level] = left_root->commit_root; |
| 5139 | extent_buffer_get(left_path->nodes[left_level]); |
| 5140 | |
| 5141 | right_level = btrfs_header_level(right_root->commit_root); |
| 5142 | right_root_level = right_level; |
| 5143 | right_path->nodes[right_level] = right_root->commit_root; |
| 5144 | extent_buffer_get(right_path->nodes[right_level]); |
| 5145 | |
| 5146 | if (left_level == 0) |
| 5147 | btrfs_item_key_to_cpu(left_path->nodes[left_level], |
| 5148 | &left_key, left_path->slots[left_level]); |
| 5149 | else |
| 5150 | btrfs_node_key_to_cpu(left_path->nodes[left_level], |
| 5151 | &left_key, left_path->slots[left_level]); |
| 5152 | if (right_level == 0) |
| 5153 | btrfs_item_key_to_cpu(right_path->nodes[right_level], |
| 5154 | &right_key, right_path->slots[right_level]); |
| 5155 | else |
| 5156 | btrfs_node_key_to_cpu(right_path->nodes[right_level], |
| 5157 | &right_key, right_path->slots[right_level]); |
| 5158 | |
| 5159 | left_end_reached = right_end_reached = 0; |
| 5160 | advance_left = advance_right = 0; |
| 5161 | |
| 5162 | while (1) { |
| 5163 | /* |
| 5164 | * We need to make sure the transaction does not get committed |
| 5165 | * while we do anything on commit roots. This means, we need to |
| 5166 | * join and leave transactions for every item that we process. |
| 5167 | */ |
| 5168 | if (trans && btrfs_should_end_transaction(trans, left_root)) { |
| 5169 | btrfs_release_path(left_path); |
| 5170 | btrfs_release_path(right_path); |
| 5171 | |
| 5172 | ret = btrfs_end_transaction(trans, left_root); |
| 5173 | trans = NULL; |
| 5174 | if (ret < 0) |
| 5175 | goto out; |
| 5176 | } |
| 5177 | /* now rejoin the transaction */ |
| 5178 | if (!trans) { |
| 5179 | trans = btrfs_join_transaction(left_root); |
| 5180 | if (IS_ERR(trans)) { |
| 5181 | ret = PTR_ERR(trans); |
| 5182 | trans = NULL; |
| 5183 | goto out; |
| 5184 | } |
| 5185 | |
| 5186 | spin_lock(&left_root->root_times_lock); |
| 5187 | ctransid = btrfs_root_ctransid(&left_root->root_item); |
| 5188 | spin_unlock(&left_root->root_times_lock); |
| 5189 | if (ctransid != left_start_ctransid) |
| 5190 | left_start_ctransid = 0; |
| 5191 | |
| 5192 | spin_lock(&right_root->root_times_lock); |
| 5193 | ctransid = btrfs_root_ctransid(&right_root->root_item); |
| 5194 | spin_unlock(&right_root->root_times_lock); |
| 5195 | if (ctransid != right_start_ctransid) |
| 5196 | right_start_ctransid = 0; |
| 5197 | |
| 5198 | if (!left_start_ctransid || !right_start_ctransid) { |
| 5199 | WARN(1, KERN_WARNING |
| 5200 | "btrfs: btrfs_compare_tree detected " |
| 5201 | "a change in one of the trees while " |
| 5202 | "iterating. This is probably a " |
| 5203 | "bug.\n"); |
| 5204 | ret = -EIO; |
| 5205 | goto out; |
| 5206 | } |
| 5207 | |
| 5208 | /* |
| 5209 | * the commit root may have changed, so start again |
| 5210 | * where we stopped |
| 5211 | */ |
| 5212 | left_path->lowest_level = left_level; |
| 5213 | right_path->lowest_level = right_level; |
| 5214 | ret = btrfs_search_slot(NULL, left_root, |
| 5215 | &left_key, left_path, 0, 0); |
| 5216 | if (ret < 0) |
| 5217 | goto out; |
| 5218 | ret = btrfs_search_slot(NULL, right_root, |
| 5219 | &right_key, right_path, 0, 0); |
| 5220 | if (ret < 0) |
| 5221 | goto out; |
| 5222 | } |
| 5223 | |
| 5224 | if (advance_left && !left_end_reached) { |
| 5225 | ret = tree_advance(left_root, left_path, &left_level, |
| 5226 | left_root_level, |
| 5227 | advance_left != ADVANCE_ONLY_NEXT, |
| 5228 | &left_key); |
| 5229 | if (ret < 0) |
| 5230 | left_end_reached = ADVANCE; |
| 5231 | advance_left = 0; |
| 5232 | } |
| 5233 | if (advance_right && !right_end_reached) { |
| 5234 | ret = tree_advance(right_root, right_path, &right_level, |
| 5235 | right_root_level, |
| 5236 | advance_right != ADVANCE_ONLY_NEXT, |
| 5237 | &right_key); |
| 5238 | if (ret < 0) |
| 5239 | right_end_reached = ADVANCE; |
| 5240 | advance_right = 0; |
| 5241 | } |
| 5242 | |
| 5243 | if (left_end_reached && right_end_reached) { |
| 5244 | ret = 0; |
| 5245 | goto out; |
| 5246 | } else if (left_end_reached) { |
| 5247 | if (right_level == 0) { |
| 5248 | ret = changed_cb(left_root, right_root, |
| 5249 | left_path, right_path, |
| 5250 | &right_key, |
| 5251 | BTRFS_COMPARE_TREE_DELETED, |
| 5252 | ctx); |
| 5253 | if (ret < 0) |
| 5254 | goto out; |
| 5255 | } |
| 5256 | advance_right = ADVANCE; |
| 5257 | continue; |
| 5258 | } else if (right_end_reached) { |
| 5259 | if (left_level == 0) { |
| 5260 | ret = changed_cb(left_root, right_root, |
| 5261 | left_path, right_path, |
| 5262 | &left_key, |
| 5263 | BTRFS_COMPARE_TREE_NEW, |
| 5264 | ctx); |
| 5265 | if (ret < 0) |
| 5266 | goto out; |
| 5267 | } |
| 5268 | advance_left = ADVANCE; |
| 5269 | continue; |
| 5270 | } |
| 5271 | |
| 5272 | if (left_level == 0 && right_level == 0) { |
| 5273 | cmp = btrfs_comp_cpu_keys(&left_key, &right_key); |
| 5274 | if (cmp < 0) { |
| 5275 | ret = changed_cb(left_root, right_root, |
| 5276 | left_path, right_path, |
| 5277 | &left_key, |
| 5278 | BTRFS_COMPARE_TREE_NEW, |
| 5279 | ctx); |
| 5280 | if (ret < 0) |
| 5281 | goto out; |
| 5282 | advance_left = ADVANCE; |
| 5283 | } else if (cmp > 0) { |
| 5284 | ret = changed_cb(left_root, right_root, |
| 5285 | left_path, right_path, |
| 5286 | &right_key, |
| 5287 | BTRFS_COMPARE_TREE_DELETED, |
| 5288 | ctx); |
| 5289 | if (ret < 0) |
| 5290 | goto out; |
| 5291 | advance_right = ADVANCE; |
| 5292 | } else { |
Chris Mason | 74dd17f | 2012-08-07 16:25:13 -0400 | [diff] [blame] | 5293 | WARN_ON(!extent_buffer_uptodate(left_path->nodes[0])); |
Alexander Block | 7069830 | 2012-06-05 21:07:48 +0200 | [diff] [blame] | 5294 | ret = tree_compare_item(left_root, left_path, |
| 5295 | right_path, tmp_buf); |
| 5296 | if (ret) { |
Chris Mason | 74dd17f | 2012-08-07 16:25:13 -0400 | [diff] [blame] | 5297 | WARN_ON(!extent_buffer_uptodate(left_path->nodes[0])); |
Alexander Block | 7069830 | 2012-06-05 21:07:48 +0200 | [diff] [blame] | 5298 | ret = changed_cb(left_root, right_root, |
| 5299 | left_path, right_path, |
| 5300 | &left_key, |
| 5301 | BTRFS_COMPARE_TREE_CHANGED, |
| 5302 | ctx); |
| 5303 | if (ret < 0) |
| 5304 | goto out; |
| 5305 | } |
| 5306 | advance_left = ADVANCE; |
| 5307 | advance_right = ADVANCE; |
| 5308 | } |
| 5309 | } else if (left_level == right_level) { |
| 5310 | cmp = btrfs_comp_cpu_keys(&left_key, &right_key); |
| 5311 | if (cmp < 0) { |
| 5312 | advance_left = ADVANCE; |
| 5313 | } else if (cmp > 0) { |
| 5314 | advance_right = ADVANCE; |
| 5315 | } else { |
| 5316 | left_blockptr = btrfs_node_blockptr( |
| 5317 | left_path->nodes[left_level], |
| 5318 | left_path->slots[left_level]); |
| 5319 | right_blockptr = btrfs_node_blockptr( |
| 5320 | right_path->nodes[right_level], |
| 5321 | right_path->slots[right_level]); |
| 5322 | if (left_blockptr == right_blockptr) { |
| 5323 | /* |
| 5324 | * As we're on a shared block, don't |
| 5325 | * allow to go deeper. |
| 5326 | */ |
| 5327 | advance_left = ADVANCE_ONLY_NEXT; |
| 5328 | advance_right = ADVANCE_ONLY_NEXT; |
| 5329 | } else { |
| 5330 | advance_left = ADVANCE; |
| 5331 | advance_right = ADVANCE; |
| 5332 | } |
| 5333 | } |
| 5334 | } else if (left_level < right_level) { |
| 5335 | advance_right = ADVANCE; |
| 5336 | } else { |
| 5337 | advance_left = ADVANCE; |
| 5338 | } |
| 5339 | } |
| 5340 | |
| 5341 | out: |
| 5342 | btrfs_free_path(left_path); |
| 5343 | btrfs_free_path(right_path); |
| 5344 | kfree(tmp_buf); |
| 5345 | |
| 5346 | if (trans) { |
| 5347 | if (!ret) |
| 5348 | ret = btrfs_end_transaction(trans, left_root); |
| 5349 | else |
| 5350 | btrfs_end_transaction(trans, left_root); |
| 5351 | } |
| 5352 | |
| 5353 | return ret; |
| 5354 | } |
| 5355 | |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5356 | /* |
| 5357 | * this is similar to btrfs_next_leaf, but does not try to preserve |
| 5358 | * and fixup the path. It looks for and returns the next key in the |
| 5359 | * tree based on the current path and the cache_only and min_trans |
| 5360 | * parameters. |
| 5361 | * |
| 5362 | * 0 is returned if another key is found, < 0 if there are any errors |
| 5363 | * and 1 is returned if there are no higher keys in the tree |
| 5364 | * |
| 5365 | * path->keep_locks should be set to 1 on the search made before |
| 5366 | * calling this function. |
| 5367 | */ |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5368 | int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path, |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 5369 | struct btrfs_key *key, int level, |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5370 | int cache_only, u64 min_trans) |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5371 | { |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5372 | int slot; |
| 5373 | struct extent_buffer *c; |
| 5374 | |
Chris Mason | 934d375 | 2008-12-08 16:43:10 -0500 | [diff] [blame] | 5375 | WARN_ON(!path->keep_locks); |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 5376 | while (level < BTRFS_MAX_LEVEL) { |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5377 | if (!path->nodes[level]) |
| 5378 | return 1; |
| 5379 | |
| 5380 | slot = path->slots[level] + 1; |
| 5381 | c = path->nodes[level]; |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5382 | next: |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5383 | if (slot >= btrfs_header_nritems(c)) { |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 5384 | int ret; |
| 5385 | int orig_lowest; |
| 5386 | struct btrfs_key cur_key; |
| 5387 | if (level + 1 >= BTRFS_MAX_LEVEL || |
| 5388 | !path->nodes[level + 1]) |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5389 | return 1; |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 5390 | |
| 5391 | if (path->locks[level + 1]) { |
| 5392 | level++; |
| 5393 | continue; |
| 5394 | } |
| 5395 | |
| 5396 | slot = btrfs_header_nritems(c) - 1; |
| 5397 | if (level == 0) |
| 5398 | btrfs_item_key_to_cpu(c, &cur_key, slot); |
| 5399 | else |
| 5400 | btrfs_node_key_to_cpu(c, &cur_key, slot); |
| 5401 | |
| 5402 | orig_lowest = path->lowest_level; |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 5403 | btrfs_release_path(path); |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 5404 | path->lowest_level = level; |
| 5405 | ret = btrfs_search_slot(NULL, root, &cur_key, path, |
| 5406 | 0, 0); |
| 5407 | path->lowest_level = orig_lowest; |
| 5408 | if (ret < 0) |
| 5409 | return ret; |
| 5410 | |
| 5411 | c = path->nodes[level]; |
| 5412 | slot = path->slots[level]; |
| 5413 | if (ret == 0) |
| 5414 | slot++; |
| 5415 | goto next; |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5416 | } |
Yan Zheng | 33c66f4 | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 5417 | |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5418 | if (level == 0) |
| 5419 | btrfs_item_key_to_cpu(c, key, slot); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5420 | else { |
| 5421 | u64 blockptr = btrfs_node_blockptr(c, slot); |
| 5422 | u64 gen = btrfs_node_ptr_generation(c, slot); |
| 5423 | |
| 5424 | if (cache_only) { |
| 5425 | struct extent_buffer *cur; |
| 5426 | cur = btrfs_find_tree_block(root, blockptr, |
| 5427 | btrfs_level_size(root, level - 1)); |
Chris Mason | b9fab91 | 2012-05-06 07:23:47 -0400 | [diff] [blame] | 5428 | if (!cur || |
| 5429 | btrfs_buffer_uptodate(cur, gen, 1) <= 0) { |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5430 | slot++; |
| 5431 | if (cur) |
| 5432 | free_extent_buffer(cur); |
| 5433 | goto next; |
| 5434 | } |
| 5435 | free_extent_buffer(cur); |
| 5436 | } |
| 5437 | if (gen < min_trans) { |
| 5438 | slot++; |
| 5439 | goto next; |
| 5440 | } |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5441 | btrfs_node_key_to_cpu(c, key, slot); |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5442 | } |
Chris Mason | e7a8456 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5443 | return 0; |
| 5444 | } |
| 5445 | return 1; |
| 5446 | } |
| 5447 | |
Chris Mason | 7bb8631 | 2007-12-11 09:25:06 -0500 | [diff] [blame] | 5448 | /* |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5449 | * search the tree again to find a leaf with greater keys |
Chris Mason | 0f70abe | 2007-02-28 16:46:22 -0500 | [diff] [blame] | 5450 | * returns 0 if it found something or 1 if there are no greater leaves. |
| 5451 | * returns < 0 on io errors. |
Chris Mason | 97571fd | 2007-02-24 13:39:08 -0500 | [diff] [blame] | 5452 | */ |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 5453 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5454 | { |
Jan Schmidt | 3d7806e | 2012-06-11 08:29:29 +0200 | [diff] [blame] | 5455 | return btrfs_next_old_leaf(root, path, 0); |
| 5456 | } |
| 5457 | |
| 5458 | int btrfs_next_old_leaf(struct btrfs_root *root, struct btrfs_path *path, |
| 5459 | u64 time_seq) |
| 5460 | { |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5461 | int slot; |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5462 | int level; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 5463 | struct extent_buffer *c; |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5464 | struct extent_buffer *next; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5465 | struct btrfs_key key; |
| 5466 | u32 nritems; |
| 5467 | int ret; |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5468 | int old_spinning = path->leave_spinning; |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5469 | int next_rw_lock = 0; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5470 | |
| 5471 | nritems = btrfs_header_nritems(path->nodes[0]); |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 5472 | if (nritems == 0) |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5473 | return 1; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5474 | |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5475 | btrfs_item_key_to_cpu(path->nodes[0], &key, nritems - 1); |
| 5476 | again: |
| 5477 | level = 1; |
| 5478 | next = NULL; |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5479 | next_rw_lock = 0; |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 5480 | btrfs_release_path(path); |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5481 | |
Chris Mason | a213501 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5482 | path->keep_locks = 1; |
Chris Mason | 31533fb | 2011-07-26 16:01:59 -0400 | [diff] [blame] | 5483 | path->leave_spinning = 1; |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5484 | |
Jan Schmidt | 3d7806e | 2012-06-11 08:29:29 +0200 | [diff] [blame] | 5485 | if (time_seq) |
| 5486 | ret = btrfs_search_old_slot(root, &key, path, time_seq); |
| 5487 | else |
| 5488 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5489 | path->keep_locks = 0; |
| 5490 | |
| 5491 | if (ret < 0) |
| 5492 | return ret; |
| 5493 | |
Chris Mason | a213501 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5494 | nritems = btrfs_header_nritems(path->nodes[0]); |
Chris Mason | 168fd7d | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5495 | /* |
| 5496 | * by releasing the path above we dropped all our locks. A balance |
| 5497 | * could have added more items next to the key that used to be |
| 5498 | * at the very end of the block. So, check again here and |
| 5499 | * advance the path if there are now more items available. |
| 5500 | */ |
Chris Mason | a213501 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5501 | if (nritems > 0 && path->slots[0] < nritems - 1) { |
Yan Zheng | e457afe | 2009-07-22 09:59:00 -0400 | [diff] [blame] | 5502 | if (ret == 0) |
| 5503 | path->slots[0]++; |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5504 | ret = 0; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5505 | goto done; |
| 5506 | } |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5507 | |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 5508 | while (level < BTRFS_MAX_LEVEL) { |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5509 | if (!path->nodes[level]) { |
| 5510 | ret = 1; |
| 5511 | goto done; |
| 5512 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 5513 | |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5514 | slot = path->slots[level] + 1; |
| 5515 | c = path->nodes[level]; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 5516 | if (slot >= btrfs_header_nritems(c)) { |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5517 | level++; |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5518 | if (level == BTRFS_MAX_LEVEL) { |
| 5519 | ret = 1; |
| 5520 | goto done; |
| 5521 | } |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5522 | continue; |
| 5523 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 5524 | |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5525 | if (next) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5526 | btrfs_tree_unlock_rw(next, next_rw_lock); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 5527 | free_extent_buffer(next); |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5528 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 5529 | |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5530 | next = c; |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5531 | next_rw_lock = path->locks[level]; |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5532 | ret = read_block_for_search(NULL, root, path, &next, level, |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 5533 | slot, &key, 0); |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5534 | if (ret == -EAGAIN) |
| 5535 | goto again; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 5536 | |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 5537 | if (ret < 0) { |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 5538 | btrfs_release_path(path); |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 5539 | goto done; |
| 5540 | } |
| 5541 | |
Chris Mason | 5cd57b2 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5542 | if (!path->skip_locking) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5543 | ret = btrfs_try_tree_read_lock(next); |
Jan Schmidt | d42244a | 2012-06-22 14:51:15 +0200 | [diff] [blame] | 5544 | if (!ret && time_seq) { |
| 5545 | /* |
| 5546 | * If we don't get the lock, we may be racing |
| 5547 | * with push_leaf_left, holding that lock while |
| 5548 | * itself waiting for the leaf we've currently |
| 5549 | * locked. To solve this situation, we give up |
| 5550 | * on our lock and cycle. |
| 5551 | */ |
Jan Schmidt | cf53883 | 2012-07-04 15:42:48 +0200 | [diff] [blame] | 5552 | free_extent_buffer(next); |
Jan Schmidt | d42244a | 2012-06-22 14:51:15 +0200 | [diff] [blame] | 5553 | btrfs_release_path(path); |
| 5554 | cond_resched(); |
| 5555 | goto again; |
| 5556 | } |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5557 | if (!ret) { |
| 5558 | btrfs_set_path_blocking(path); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5559 | btrfs_tree_read_lock(next); |
Chris Mason | 31533fb | 2011-07-26 16:01:59 -0400 | [diff] [blame] | 5560 | btrfs_clear_path_blocking(path, next, |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5561 | BTRFS_READ_LOCK); |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5562 | } |
Chris Mason | 31533fb | 2011-07-26 16:01:59 -0400 | [diff] [blame] | 5563 | next_rw_lock = BTRFS_READ_LOCK; |
Chris Mason | 5cd57b2 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5564 | } |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5565 | break; |
| 5566 | } |
| 5567 | path->slots[level] = slot; |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 5568 | while (1) { |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5569 | level--; |
| 5570 | c = path->nodes[level]; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5571 | if (path->locks[level]) |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5572 | btrfs_tree_unlock_rw(c, path->locks[level]); |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5573 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 5574 | free_extent_buffer(c); |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5575 | path->nodes[level] = next; |
| 5576 | path->slots[level] = 0; |
Chris Mason | a74a4b9 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5577 | if (!path->skip_locking) |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5578 | path->locks[level] = next_rw_lock; |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5579 | if (!level) |
| 5580 | break; |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 5581 | |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5582 | ret = read_block_for_search(NULL, root, path, &next, level, |
Jan Schmidt | 5d9e75c4 | 2012-05-16 18:25:47 +0200 | [diff] [blame] | 5583 | 0, &key, 0); |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5584 | if (ret == -EAGAIN) |
| 5585 | goto again; |
| 5586 | |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 5587 | if (ret < 0) { |
David Sterba | b3b4aa7 | 2011-04-21 01:20:15 +0200 | [diff] [blame] | 5588 | btrfs_release_path(path); |
Chris Mason | 76a05b3 | 2009-05-14 13:24:30 -0400 | [diff] [blame] | 5589 | goto done; |
| 5590 | } |
| 5591 | |
Chris Mason | 5cd57b2 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5592 | if (!path->skip_locking) { |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5593 | ret = btrfs_try_tree_read_lock(next); |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5594 | if (!ret) { |
| 5595 | btrfs_set_path_blocking(path); |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5596 | btrfs_tree_read_lock(next); |
Chris Mason | 31533fb | 2011-07-26 16:01:59 -0400 | [diff] [blame] | 5597 | btrfs_clear_path_blocking(path, next, |
Chris Mason | bd68151 | 2011-07-16 15:23:14 -0400 | [diff] [blame] | 5598 | BTRFS_READ_LOCK); |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5599 | } |
Chris Mason | 31533fb | 2011-07-26 16:01:59 -0400 | [diff] [blame] | 5600 | next_rw_lock = BTRFS_READ_LOCK; |
Chris Mason | 5cd57b2 | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5601 | } |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5602 | } |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5603 | ret = 0; |
Chris Mason | 925baed | 2008-06-25 16:01:30 -0400 | [diff] [blame] | 5604 | done: |
Chris Mason | f7c79f3 | 2012-03-19 15:54:38 -0400 | [diff] [blame] | 5605 | unlock_up(path, 0, 1, 0, NULL); |
Chris Mason | 8e73f27 | 2009-04-03 10:14:18 -0400 | [diff] [blame] | 5606 | path->leave_spinning = old_spinning; |
| 5607 | if (!old_spinning) |
| 5608 | btrfs_set_path_blocking(path); |
| 5609 | |
| 5610 | return ret; |
Chris Mason | d97e63b | 2007-02-20 16:40:44 -0500 | [diff] [blame] | 5611 | } |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 5612 | |
Chris Mason | 3f157a2 | 2008-06-25 16:01:31 -0400 | [diff] [blame] | 5613 | /* |
| 5614 | * this uses btrfs_prev_leaf to walk backwards in the tree, and keeps |
| 5615 | * searching until it gets past min_objectid or finds an item of 'type' |
| 5616 | * |
| 5617 | * returns 0 if something is found, 1 if nothing was found and < 0 on error |
| 5618 | */ |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 5619 | int btrfs_previous_item(struct btrfs_root *root, |
| 5620 | struct btrfs_path *path, u64 min_objectid, |
| 5621 | int type) |
| 5622 | { |
| 5623 | struct btrfs_key found_key; |
| 5624 | struct extent_buffer *leaf; |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 5625 | u32 nritems; |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 5626 | int ret; |
| 5627 | |
Chris Mason | d397712 | 2009-01-05 21:25:51 -0500 | [diff] [blame] | 5628 | while (1) { |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 5629 | if (path->slots[0] == 0) { |
Chris Mason | b4ce94d | 2009-02-04 09:25:08 -0500 | [diff] [blame] | 5630 | btrfs_set_path_blocking(path); |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 5631 | ret = btrfs_prev_leaf(root, path); |
| 5632 | if (ret != 0) |
| 5633 | return ret; |
| 5634 | } else { |
| 5635 | path->slots[0]--; |
| 5636 | } |
| 5637 | leaf = path->nodes[0]; |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 5638 | nritems = btrfs_header_nritems(leaf); |
| 5639 | if (nritems == 0) |
| 5640 | return 1; |
| 5641 | if (path->slots[0] == nritems) |
| 5642 | path->slots[0]--; |
| 5643 | |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 5644 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 5645 | if (found_key.objectid < min_objectid) |
| 5646 | break; |
Yan Zheng | 0a4eefb | 2009-07-24 11:06:53 -0400 | [diff] [blame] | 5647 | if (found_key.type == type) |
| 5648 | return 0; |
Chris Mason | e02119d | 2008-09-05 16:13:11 -0400 | [diff] [blame] | 5649 | if (found_key.objectid == min_objectid && |
| 5650 | found_key.type < type) |
| 5651 | break; |
Chris Mason | 0b86a83 | 2008-03-24 15:01:56 -0400 | [diff] [blame] | 5652 | } |
| 5653 | return 1; |
| 5654 | } |