Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 1 | #include <stdio.h> |
| 2 | #include <stdlib.h> |
| 3 | #include "kerncompat.h" |
| 4 | #include "radix-tree.h" |
| 5 | #include "ctree.h" |
| 6 | #include "disk-io.h" |
| 7 | #include "print-tree.h" |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 8 | #include "transaction.h" |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 9 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 10 | static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 11 | *orig_root, u64 num_blocks, u64 search_start, u64 |
| 12 | search_end, struct btrfs_key *ins); |
| 13 | static int finish_current_insert(struct btrfs_trans_handle *trans, struct |
| 14 | btrfs_root *extent_root); |
| 15 | static int run_pending(struct btrfs_trans_handle *trans, struct btrfs_root |
| 16 | *extent_root); |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 17 | |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 18 | /* |
| 19 | * pending extents are blocks that we're trying to allocate in the extent |
| 20 | * map while trying to grow the map because of other allocations. To avoid |
| 21 | * recursing, they are tagged in the radix tree and cleaned up after |
| 22 | * other allocations are done. The pending tag is also used in the same |
| 23 | * manner for deletes. |
| 24 | */ |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 25 | #define CTREE_EXTENT_PENDING_DEL 0 |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 26 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 27 | static int inc_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root |
| 28 | *root, u64 blocknr) |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 29 | { |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 30 | struct btrfs_path path; |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 31 | int ret; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 32 | struct btrfs_key key; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 33 | struct btrfs_leaf *l; |
| 34 | struct btrfs_extent_item *item; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 35 | struct btrfs_key ins; |
Chris Mason | cf27e1e | 2007-03-13 09:49:06 -0400 | [diff] [blame] | 36 | u32 refs; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 37 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 38 | find_free_extent(trans, root->extent_root, 0, 0, (u64)-1, &ins); |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 39 | btrfs_init_path(&path); |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 40 | key.objectid = blocknr; |
| 41 | key.flags = 0; |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 42 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 43 | key.offset = 1; |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 44 | ret = btrfs_search_slot(trans, root->extent_root, &key, &path, 0, 1); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 45 | if (ret != 0) |
| 46 | BUG(); |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 47 | BUG_ON(ret != 0); |
| 48 | l = &path.nodes[0]->leaf; |
Chris Mason | 4beb1b8 | 2007-03-14 10:31:29 -0400 | [diff] [blame] | 49 | item = btrfs_item_ptr(l, path.slots[0], struct btrfs_extent_item); |
Chris Mason | cf27e1e | 2007-03-13 09:49:06 -0400 | [diff] [blame] | 50 | refs = btrfs_extent_refs(item); |
| 51 | btrfs_set_extent_refs(item, refs + 1); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 52 | |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 53 | BUG_ON(list_empty(&path.nodes[0]->dirty)); |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 54 | btrfs_release_path(root->extent_root, &path); |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 55 | finish_current_insert(trans, root->extent_root); |
| 56 | run_pending(trans, root->extent_root); |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 57 | return 0; |
| 58 | } |
| 59 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 60 | static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root |
| 61 | *root, u64 blocknr, u32 *refs) |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 62 | { |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 63 | struct btrfs_path path; |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 64 | int ret; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 65 | struct btrfs_key key; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 66 | struct btrfs_leaf *l; |
| 67 | struct btrfs_extent_item *item; |
| 68 | btrfs_init_path(&path); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 69 | key.objectid = blocknr; |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 70 | key.offset = 1; |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 71 | key.flags = 0; |
| 72 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 73 | ret = btrfs_search_slot(trans, root->extent_root, &key, &path, 0, 0); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 74 | if (ret != 0) |
| 75 | BUG(); |
| 76 | l = &path.nodes[0]->leaf; |
Chris Mason | 4beb1b8 | 2007-03-14 10:31:29 -0400 | [diff] [blame] | 77 | item = btrfs_item_ptr(l, path.slots[0], struct btrfs_extent_item); |
Chris Mason | cf27e1e | 2007-03-13 09:49:06 -0400 | [diff] [blame] | 78 | *refs = btrfs_extent_refs(item); |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 79 | btrfs_release_path(root->extent_root, &path); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 80 | return 0; |
| 81 | } |
| 82 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 83 | int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
| 84 | struct btrfs_buffer *buf) |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 85 | { |
| 86 | u64 blocknr; |
| 87 | int i; |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 88 | |
Chris Mason | 3768f36 | 2007-03-13 16:47:54 -0400 | [diff] [blame] | 89 | if (!root->ref_cows) |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 90 | return 0; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 91 | if (btrfs_is_leaf(&buf->node)) |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 92 | return 0; |
| 93 | |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 94 | for (i = 0; i < btrfs_header_nritems(&buf->node.header); i++) { |
Chris Mason | 1d4f8a0 | 2007-03-13 09:28:32 -0400 | [diff] [blame] | 95 | blocknr = btrfs_node_blockptr(&buf->node, i); |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 96 | inc_block_ref(trans, root, blocknr); |
Chris Mason | 02217ed | 2007-03-02 16:08:05 -0500 | [diff] [blame] | 97 | } |
| 98 | return 0; |
| 99 | } |
| 100 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 101 | int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct |
| 102 | btrfs_root *root) |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 103 | { |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 104 | unsigned long gang[8]; |
Chris Mason | 88fd146 | 2007-03-16 08:56:18 -0400 | [diff] [blame] | 105 | u64 first = 0; |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 106 | int ret; |
| 107 | int i; |
| 108 | |
| 109 | while(1) { |
Chris Mason | 3768f36 | 2007-03-13 16:47:54 -0400 | [diff] [blame] | 110 | ret = radix_tree_gang_lookup(&root->pinned_radix, |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 111 | (void **)gang, 0, |
| 112 | ARRAY_SIZE(gang)); |
| 113 | if (!ret) |
| 114 | break; |
Chris Mason | 88fd146 | 2007-03-16 08:56:18 -0400 | [diff] [blame] | 115 | if (!first) |
| 116 | first = gang[0]; |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 117 | for (i = 0; i < ret; i++) { |
Chris Mason | 3768f36 | 2007-03-13 16:47:54 -0400 | [diff] [blame] | 118 | radix_tree_delete(&root->pinned_radix, gang[i]); |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 119 | } |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 120 | } |
Chris Mason | 88fd146 | 2007-03-16 08:56:18 -0400 | [diff] [blame] | 121 | root->last_insert.objectid = first; |
Chris Mason | 3768f36 | 2007-03-13 16:47:54 -0400 | [diff] [blame] | 122 | root->last_insert.offset = 0; |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 123 | return 0; |
| 124 | } |
| 125 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 126 | static int finish_current_insert(struct btrfs_trans_handle *trans, struct |
| 127 | btrfs_root *extent_root) |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 128 | { |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 129 | struct btrfs_key ins; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 130 | struct btrfs_extent_item extent_item; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 131 | int i; |
| 132 | int ret; |
| 133 | |
Chris Mason | cf27e1e | 2007-03-13 09:49:06 -0400 | [diff] [blame] | 134 | btrfs_set_extent_refs(&extent_item, 1); |
| 135 | btrfs_set_extent_owner(&extent_item, |
| 136 | btrfs_header_parentid(&extent_root->node->node.header)); |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 137 | ins.offset = 1; |
| 138 | ins.flags = 0; |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 139 | btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY); |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 140 | |
| 141 | for (i = 0; i < extent_root->current_insert.flags; i++) { |
| 142 | ins.objectid = extent_root->current_insert.objectid + i; |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 143 | ret = btrfs_insert_item(trans, extent_root, &ins, &extent_item, |
| 144 | sizeof(extent_item)); |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 145 | BUG_ON(ret); |
| 146 | } |
| 147 | extent_root->current_insert.offset = 0; |
| 148 | return 0; |
| 149 | } |
| 150 | |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 151 | /* |
| 152 | * remove an extent from the root, returns 0 on success |
| 153 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 154 | static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 155 | *root, u64 blocknr, u64 num_blocks, int pin) |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 156 | { |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 157 | struct btrfs_path path; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 158 | struct btrfs_key key; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 159 | struct btrfs_root *extent_root = root->extent_root; |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 160 | int ret; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 161 | struct btrfs_extent_item *ei; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 162 | struct btrfs_key ins; |
Chris Mason | cf27e1e | 2007-03-13 09:49:06 -0400 | [diff] [blame] | 163 | u32 refs; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 164 | |
Chris Mason | 88fd146 | 2007-03-16 08:56:18 -0400 | [diff] [blame] | 165 | BUG_ON(pin && num_blocks != 1); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 166 | key.objectid = blocknr; |
| 167 | key.flags = 0; |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 168 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 169 | key.offset = num_blocks; |
| 170 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 171 | find_free_extent(trans, root, 0, 0, (u64)-1, &ins); |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 172 | btrfs_init_path(&path); |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 173 | ret = btrfs_search_slot(trans, extent_root, &key, &path, -1, 1); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 174 | if (ret) { |
| 175 | printf("failed to find %Lu\n", key.objectid); |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 176 | btrfs_print_tree(extent_root, extent_root->node); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 177 | printf("failed to find %Lu\n", key.objectid); |
| 178 | BUG(); |
| 179 | } |
Chris Mason | 123abc8 | 2007-03-14 14:14:43 -0400 | [diff] [blame] | 180 | ei = btrfs_item_ptr(&path.nodes[0]->leaf, path.slots[0], |
| 181 | struct btrfs_extent_item); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 182 | BUG_ON(ei->refs == 0); |
Chris Mason | cf27e1e | 2007-03-13 09:49:06 -0400 | [diff] [blame] | 183 | refs = btrfs_extent_refs(ei) - 1; |
| 184 | btrfs_set_extent_refs(ei, refs); |
| 185 | if (refs == 0) { |
Chris Mason | 88fd146 | 2007-03-16 08:56:18 -0400 | [diff] [blame] | 186 | if (pin) { |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 187 | int err; |
| 188 | radix_tree_preload(GFP_KERNEL); |
| 189 | err = radix_tree_insert(&extent_root->pinned_radix, |
| 190 | blocknr, (void *)blocknr); |
| 191 | BUG_ON(err); |
| 192 | radix_tree_preload_end(); |
| 193 | } |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 194 | ret = btrfs_del_item(trans, extent_root, &path); |
Chris Mason | 88fd146 | 2007-03-16 08:56:18 -0400 | [diff] [blame] | 195 | if (!pin && extent_root->last_insert.objectid > blocknr) |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 196 | extent_root->last_insert.objectid = blocknr; |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 197 | if (ret) |
| 198 | BUG(); |
| 199 | } |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 200 | btrfs_release_path(extent_root, &path); |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 201 | finish_current_insert(trans, extent_root); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 202 | return ret; |
| 203 | } |
| 204 | |
| 205 | /* |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 206 | * find all the blocks marked as pending in the radix tree and remove |
| 207 | * them from the extent map |
| 208 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 209 | static int del_pending_extents(struct btrfs_trans_handle *trans, struct |
| 210 | btrfs_root *extent_root) |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 211 | { |
| 212 | int ret; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 213 | struct btrfs_buffer *gang[4]; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 214 | int i; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 215 | |
| 216 | while(1) { |
| 217 | ret = radix_tree_gang_lookup_tag(&extent_root->cache_radix, |
| 218 | (void **)gang, 0, |
| 219 | ARRAY_SIZE(gang), |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 220 | CTREE_EXTENT_PENDING_DEL); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 221 | if (!ret) |
| 222 | break; |
| 223 | for (i = 0; i < ret; i++) { |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 224 | ret = __free_extent(trans, extent_root, |
Chris Mason | 88fd146 | 2007-03-16 08:56:18 -0400 | [diff] [blame] | 225 | gang[i]->blocknr, 1, 1); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 226 | radix_tree_tag_clear(&extent_root->cache_radix, |
| 227 | gang[i]->blocknr, |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 228 | CTREE_EXTENT_PENDING_DEL); |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 229 | btrfs_block_release(extent_root, gang[i]); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 230 | } |
| 231 | } |
| 232 | return 0; |
| 233 | } |
| 234 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 235 | static int run_pending(struct btrfs_trans_handle *trans, struct btrfs_root |
| 236 | *extent_root) |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 237 | { |
| 238 | while(radix_tree_tagged(&extent_root->cache_radix, |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 239 | CTREE_EXTENT_PENDING_DEL)) |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 240 | del_pending_extents(trans, extent_root); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 241 | return 0; |
| 242 | } |
| 243 | |
| 244 | |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 245 | /* |
| 246 | * remove an extent from the root, returns 0 on success |
| 247 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 248 | int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 249 | *root, u64 blocknr, u64 num_blocks, int pin) |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 250 | { |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 251 | struct btrfs_root *extent_root = root->extent_root; |
| 252 | struct btrfs_buffer *t; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 253 | int pending_ret; |
| 254 | int ret; |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 255 | |
| 256 | if (root == extent_root) { |
| 257 | t = find_tree_block(root, blocknr); |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 258 | radix_tree_tag_set(&root->cache_radix, blocknr, |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 259 | CTREE_EXTENT_PENDING_DEL); |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 260 | return 0; |
| 261 | } |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 262 | ret = __free_extent(trans, root, blocknr, num_blocks, pin); |
| 263 | pending_ret = run_pending(trans, root->extent_root); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 264 | return ret ? ret : pending_ret; |
| 265 | } |
| 266 | |
| 267 | /* |
| 268 | * walks the btree of allocated extents and find a hole of a given size. |
| 269 | * The key ins is changed to record the hole: |
| 270 | * ins->objectid == block start |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 271 | * ins->flags = BTRFS_EXTENT_ITEM_KEY |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 272 | * ins->offset == number of blocks |
| 273 | * Any available blocks before search_start are skipped. |
| 274 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 275 | static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 276 | *orig_root, u64 num_blocks, u64 search_start, u64 |
| 277 | search_end, struct btrfs_key *ins) |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 278 | { |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 279 | struct btrfs_path path; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 280 | struct btrfs_key key; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 281 | int ret; |
| 282 | u64 hole_size = 0; |
| 283 | int slot = 0; |
| 284 | u64 last_block; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 285 | u64 test_block; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 286 | int start_found; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 287 | struct btrfs_leaf *l; |
| 288 | struct btrfs_root * root = orig_root->extent_root; |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 289 | int total_needed = num_blocks; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 290 | |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 291 | total_needed += (btrfs_header_level(&root->node->node.header) + 1) * 3; |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 292 | if (root->last_insert.objectid > search_start) |
| 293 | search_start = root->last_insert.objectid; |
Chris Mason | 62e2749 | 2007-03-15 12:56:47 -0400 | [diff] [blame] | 294 | |
| 295 | ins->flags = 0; |
| 296 | btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY); |
| 297 | |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 298 | check_failed: |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 299 | btrfs_init_path(&path); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 300 | ins->objectid = search_start; |
| 301 | ins->offset = 0; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 302 | start_found = 0; |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 303 | ret = btrfs_search_slot(trans, root, ins, &path, 0, 0); |
Chris Mason | 0f70abe | 2007-02-28 16:46:22 -0500 | [diff] [blame] | 304 | if (ret < 0) |
| 305 | goto error; |
Chris Mason | aa5d6be | 2007-02-28 16:35:06 -0500 | [diff] [blame] | 306 | |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 307 | if (path.slots[0] > 0) |
| 308 | path.slots[0]--; |
| 309 | |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 310 | while (1) { |
| 311 | l = &path.nodes[0]->leaf; |
| 312 | slot = path.slots[0]; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 313 | if (slot >= btrfs_header_nritems(&l->header)) { |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 314 | ret = btrfs_next_leaf(root, &path); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 315 | if (ret == 0) |
| 316 | continue; |
Chris Mason | 0f70abe | 2007-02-28 16:46:22 -0500 | [diff] [blame] | 317 | if (ret < 0) |
| 318 | goto error; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 319 | if (!start_found) { |
| 320 | ins->objectid = search_start; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 321 | ins->offset = (u64)-1; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 322 | start_found = 1; |
| 323 | goto check_pending; |
| 324 | } |
| 325 | ins->objectid = last_block > search_start ? |
| 326 | last_block : search_start; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 327 | ins->offset = (u64)-1; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 328 | goto check_pending; |
| 329 | } |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 330 | btrfs_disk_key_to_cpu(&key, &l->items[slot].key); |
| 331 | if (key.objectid >= search_start) { |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 332 | if (start_found) { |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 333 | if (last_block < search_start) |
| 334 | last_block = search_start; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 335 | hole_size = key.objectid - last_block; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 336 | if (hole_size > total_needed) { |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 337 | ins->objectid = last_block; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 338 | ins->offset = hole_size; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 339 | goto check_pending; |
| 340 | } |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 341 | } |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 342 | } |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 343 | start_found = 1; |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 344 | last_block = key.objectid + key.offset; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 345 | path.slots[0]++; |
| 346 | } |
| 347 | // FIXME -ENOSPC |
| 348 | check_pending: |
| 349 | /* we have to make sure we didn't find an extent that has already |
| 350 | * been allocated by the map tree or the original allocation |
| 351 | */ |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 352 | btrfs_release_path(root, &path); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 353 | BUG_ON(ins->objectid < search_start); |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 354 | for (test_block = ins->objectid; |
| 355 | test_block < ins->objectid + total_needed; test_block++) { |
| 356 | if (radix_tree_lookup(&root->pinned_radix, test_block)) { |
| 357 | search_start = test_block + 1; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 358 | goto check_failed; |
| 359 | } |
| 360 | } |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 361 | BUG_ON(root->current_insert.offset); |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 362 | root->current_insert.offset = total_needed - num_blocks; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 363 | root->current_insert.objectid = ins->objectid + num_blocks; |
| 364 | root->current_insert.flags = 0; |
Chris Mason | 0579da4 | 2007-03-07 16:15:30 -0500 | [diff] [blame] | 365 | root->last_insert.objectid = ins->objectid; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 366 | ins->offset = num_blocks; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 367 | return 0; |
Chris Mason | 0f70abe | 2007-02-28 16:46:22 -0500 | [diff] [blame] | 368 | error: |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 369 | btrfs_release_path(root, &path); |
Chris Mason | 0f70abe | 2007-02-28 16:46:22 -0500 | [diff] [blame] | 370 | return ret; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 371 | } |
| 372 | |
| 373 | /* |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 374 | * finds a free extent and does all the dirty work required for allocation |
| 375 | * returns the key for the extent through ins, and a tree buffer for |
| 376 | * the first block of the extent through buf. |
| 377 | * |
| 378 | * returns 0 if everything worked, non-zero otherwise. |
| 379 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 380 | static int alloc_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 381 | *root, u64 num_blocks, u64 search_start, u64 |
| 382 | search_end, u64 owner, struct btrfs_key *ins) |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 383 | { |
| 384 | int ret; |
| 385 | int pending_ret; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 386 | struct btrfs_root *extent_root = root->extent_root; |
| 387 | struct btrfs_extent_item extent_item; |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 388 | |
Chris Mason | cf27e1e | 2007-03-13 09:49:06 -0400 | [diff] [blame] | 389 | btrfs_set_extent_refs(&extent_item, 1); |
| 390 | btrfs_set_extent_owner(&extent_item, owner); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 391 | |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 392 | if (root == extent_root) { |
| 393 | BUG_ON(extent_root->current_insert.offset == 0); |
| 394 | BUG_ON(num_blocks != 1); |
| 395 | BUG_ON(extent_root->current_insert.flags == |
| 396 | extent_root->current_insert.offset); |
| 397 | ins->offset = 1; |
| 398 | ins->objectid = extent_root->current_insert.objectid + |
| 399 | extent_root->current_insert.flags++; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 400 | return 0; |
| 401 | } |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 402 | ret = find_free_extent(trans, root, num_blocks, search_start, |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 403 | search_end, ins); |
| 404 | if (ret) |
| 405 | return ret; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 406 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 407 | ret = btrfs_insert_item(trans, extent_root, ins, &extent_item, |
| 408 | sizeof(extent_item)); |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 409 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 410 | finish_current_insert(trans, extent_root); |
| 411 | pending_ret = run_pending(trans, extent_root); |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 412 | if (ret) |
| 413 | return ret; |
| 414 | if (pending_ret) |
| 415 | return pending_ret; |
| 416 | return 0; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 417 | } |
| 418 | |
| 419 | /* |
| 420 | * helper function to allocate a block for a given tree |
| 421 | * returns the tree buffer or NULL. |
| 422 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 423 | struct btrfs_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, |
| 424 | struct btrfs_root *root) |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 425 | { |
Chris Mason | e2fa722 | 2007-03-12 16:22:34 -0400 | [diff] [blame] | 426 | struct btrfs_key ins; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 427 | int ret; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 428 | struct btrfs_buffer *buf; |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 429 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 430 | ret = alloc_extent(trans, root, 1, 0, (unsigned long)-1, |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 431 | btrfs_header_parentid(&root->node->node.header), |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 432 | &ins); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 433 | if (ret) { |
| 434 | BUG(); |
| 435 | return NULL; |
| 436 | } |
Chris Mason | 037e639 | 2007-03-07 11:50:24 -0500 | [diff] [blame] | 437 | buf = find_tree_block(root, ins.objectid); |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 438 | dirty_tree_block(trans, root, buf); |
Chris Mason | fec577f | 2007-02-26 10:40:21 -0500 | [diff] [blame] | 439 | return buf; |
| 440 | } |
Chris Mason | a28ec19 | 2007-03-06 20:08:01 -0500 | [diff] [blame] | 441 | |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 442 | /* |
| 443 | * helper function for drop_snapshot, this walks down the tree dropping ref |
| 444 | * counts as it goes. |
| 445 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 446 | static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root |
| 447 | *root, struct btrfs_path *path, int *level) |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 448 | { |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 449 | struct btrfs_buffer *next; |
| 450 | struct btrfs_buffer *cur; |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 451 | u64 blocknr; |
| 452 | int ret; |
| 453 | u32 refs; |
| 454 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 455 | ret = lookup_block_ref(trans, root, path->nodes[*level]->blocknr, |
| 456 | &refs); |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 457 | BUG_ON(ret); |
| 458 | if (refs > 1) |
| 459 | goto out; |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 460 | /* |
| 461 | * walk down to the last node level and free all the leaves |
| 462 | */ |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 463 | while(*level > 0) { |
| 464 | cur = path->nodes[*level]; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 465 | if (path->slots[*level] >= |
| 466 | btrfs_header_nritems(&cur->node.header)) |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 467 | break; |
Chris Mason | 1d4f8a0 | 2007-03-13 09:28:32 -0400 | [diff] [blame] | 468 | blocknr = btrfs_node_blockptr(&cur->node, path->slots[*level]); |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 469 | ret = lookup_block_ref(trans, root, blocknr, &refs); |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 470 | if (refs != 1 || *level == 1) { |
| 471 | path->slots[*level]++; |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 472 | ret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 473 | BUG_ON(ret); |
| 474 | continue; |
| 475 | } |
| 476 | BUG_ON(ret); |
| 477 | next = read_tree_block(root, blocknr); |
Chris Mason | 83e15a2 | 2007-03-12 09:03:27 -0400 | [diff] [blame] | 478 | if (path->nodes[*level-1]) |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 479 | btrfs_block_release(root, path->nodes[*level-1]); |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 480 | path->nodes[*level-1] = next; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 481 | *level = btrfs_header_level(&next->node.header); |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 482 | path->slots[*level] = 0; |
| 483 | } |
| 484 | out: |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 485 | ret = btrfs_free_extent(trans, root, path->nodes[*level]->blocknr, 1, |
| 486 | 1); |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 487 | btrfs_block_release(root, path->nodes[*level]); |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 488 | path->nodes[*level] = NULL; |
| 489 | *level += 1; |
| 490 | BUG_ON(ret); |
| 491 | return 0; |
| 492 | } |
| 493 | |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 494 | /* |
| 495 | * helper for dropping snapshots. This walks back up the tree in the path |
| 496 | * to find the first node higher up where we haven't yet gone through |
| 497 | * all the slots |
| 498 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 499 | static int walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root |
| 500 | *root, struct btrfs_path *path, int *level) |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 501 | { |
| 502 | int i; |
| 503 | int slot; |
| 504 | int ret; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 505 | for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) { |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 506 | slot = path->slots[i]; |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 507 | if (slot < |
| 508 | btrfs_header_nritems(&path->nodes[i]->node.header)- 1) { |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 509 | path->slots[i]++; |
| 510 | *level = i; |
| 511 | return 0; |
| 512 | } else { |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 513 | ret = btrfs_free_extent(trans, root, |
| 514 | path->nodes[*level]->blocknr, |
| 515 | 1, 1); |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 516 | btrfs_block_release(root, path->nodes[*level]); |
Chris Mason | 83e15a2 | 2007-03-12 09:03:27 -0400 | [diff] [blame] | 517 | path->nodes[*level] = NULL; |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 518 | *level = i + 1; |
| 519 | BUG_ON(ret); |
| 520 | } |
| 521 | } |
| 522 | return 1; |
| 523 | } |
| 524 | |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 525 | /* |
| 526 | * drop the reference count on the tree rooted at 'snap'. This traverses |
| 527 | * the tree freeing any blocks that have a ref count of zero after being |
| 528 | * decremented. |
| 529 | */ |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 530 | int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root |
| 531 | *root, struct btrfs_buffer *snap) |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 532 | { |
Chris Mason | 3768f36 | 2007-03-13 16:47:54 -0400 | [diff] [blame] | 533 | int ret = 0; |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 534 | int wret; |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 535 | int level; |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 536 | struct btrfs_path path; |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 537 | int i; |
| 538 | int orig_level; |
| 539 | |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 540 | btrfs_init_path(&path); |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 541 | |
Chris Mason | 7518a23 | 2007-03-12 12:01:18 -0400 | [diff] [blame] | 542 | level = btrfs_header_level(&snap->node.header); |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 543 | orig_level = level; |
| 544 | path.nodes[level] = snap; |
| 545 | path.slots[level] = 0; |
| 546 | while(1) { |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 547 | wret = walk_down_tree(trans, root, &path, &level); |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 548 | if (wret > 0) |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 549 | break; |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 550 | if (wret < 0) |
| 551 | ret = wret; |
| 552 | |
Chris Mason | e089f05 | 2007-03-16 16:20:31 -0400 | [diff] [blame^] | 553 | wret = walk_up_tree(trans, root, &path, &level); |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 554 | if (wret > 0) |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 555 | break; |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 556 | if (wret < 0) |
| 557 | ret = wret; |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 558 | } |
Chris Mason | 83e15a2 | 2007-03-12 09:03:27 -0400 | [diff] [blame] | 559 | for (i = 0; i <= orig_level; i++) { |
| 560 | if (path.nodes[i]) { |
Chris Mason | 234b63a | 2007-03-13 10:46:10 -0400 | [diff] [blame] | 561 | btrfs_block_release(root, path.nodes[i]); |
Chris Mason | 83e15a2 | 2007-03-12 09:03:27 -0400 | [diff] [blame] | 562 | } |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 563 | } |
Chris Mason | 9aca1d5 | 2007-03-13 11:09:37 -0400 | [diff] [blame] | 564 | return ret; |
Chris Mason | 20524f0 | 2007-03-10 06:35:47 -0500 | [diff] [blame] | 565 | } |