Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2 | * linux/fs/ext4/inode.c |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3 | * |
| 4 | * Copyright (C) 1992, 1993, 1994, 1995 |
| 5 | * Remy Card (card@masi.ibp.fr) |
| 6 | * Laboratoire MASI - Institut Blaise Pascal |
| 7 | * Universite Pierre et Marie Curie (Paris VI) |
| 8 | * |
| 9 | * from |
| 10 | * |
| 11 | * linux/fs/minix/inode.c |
| 12 | * |
| 13 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 14 | * |
| 15 | * Goal-directed block allocation by Stephen Tweedie |
| 16 | * (sct@redhat.com), 1993, 1998 |
| 17 | * Big-endian to little-endian byte-swapping/bitmaps by |
| 18 | * David S. Miller (davem@caip.rutgers.edu), 1995 |
| 19 | * 64-bit file support on 64-bit platforms by Jakub Jelinek |
| 20 | * (jj@sunsite.ms.mff.cuni.cz) |
| 21 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 22 | * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000 |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 23 | */ |
| 24 | |
| 25 | #include <linux/module.h> |
| 26 | #include <linux/fs.h> |
| 27 | #include <linux/time.h> |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 28 | #include <linux/ext4_jbd2.h> |
| 29 | #include <linux/jbd2.h> |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 30 | #include <linux/highuid.h> |
| 31 | #include <linux/pagemap.h> |
| 32 | #include <linux/quotaops.h> |
| 33 | #include <linux/string.h> |
| 34 | #include <linux/buffer_head.h> |
| 35 | #include <linux/writeback.h> |
| 36 | #include <linux/mpage.h> |
| 37 | #include <linux/uio.h> |
| 38 | #include <linux/bio.h> |
| 39 | #include "xattr.h" |
| 40 | #include "acl.h" |
| 41 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 42 | /* |
| 43 | * Test whether an inode is a fast symlink. |
| 44 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 45 | static int ext4_inode_is_fast_symlink(struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 46 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 47 | int ea_blocks = EXT4_I(inode)->i_file_acl ? |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 48 | (inode->i_sb->s_blocksize >> 9) : 0; |
| 49 | |
| 50 | return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); |
| 51 | } |
| 52 | |
| 53 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 54 | * The ext4 forget function must perform a revoke if we are freeing data |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 55 | * which has been journaled. Metadata (eg. indirect blocks) must be |
| 56 | * revoked in all cases. |
| 57 | * |
| 58 | * "bh" may be NULL: a metadata block may have been freed from memory |
| 59 | * but there may still be a record of it in the journal, and that record |
| 60 | * still needs to be revoked. |
| 61 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 62 | int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode, |
| 63 | struct buffer_head *bh, ext4_fsblk_t blocknr) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 64 | { |
| 65 | int err; |
| 66 | |
| 67 | might_sleep(); |
| 68 | |
| 69 | BUFFER_TRACE(bh, "enter"); |
| 70 | |
| 71 | jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " |
| 72 | "data mode %lx\n", |
| 73 | bh, is_metadata, inode->i_mode, |
| 74 | test_opt(inode->i_sb, DATA_FLAGS)); |
| 75 | |
| 76 | /* Never use the revoke function if we are doing full data |
| 77 | * journaling: there is no need to, and a V1 superblock won't |
| 78 | * support it. Otherwise, only skip the revoke on un-journaled |
| 79 | * data blocks. */ |
| 80 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 81 | if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || |
| 82 | (!is_metadata && !ext4_should_journal_data(inode))) { |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 83 | if (bh) { |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 84 | BUFFER_TRACE(bh, "call jbd2_journal_forget"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 85 | return ext4_journal_forget(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 86 | } |
| 87 | return 0; |
| 88 | } |
| 89 | |
| 90 | /* |
| 91 | * data!=journal && (is_metadata || should_journal_data(inode)) |
| 92 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 93 | BUFFER_TRACE(bh, "call ext4_journal_revoke"); |
| 94 | err = ext4_journal_revoke(handle, blocknr, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 95 | if (err) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 96 | ext4_abort(inode->i_sb, __FUNCTION__, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 97 | "error %d when attempting revoke", err); |
| 98 | BUFFER_TRACE(bh, "exit"); |
| 99 | return err; |
| 100 | } |
| 101 | |
| 102 | /* |
| 103 | * Work out how many blocks we need to proceed with the next chunk of a |
| 104 | * truncate transaction. |
| 105 | */ |
| 106 | static unsigned long blocks_for_truncate(struct inode *inode) |
| 107 | { |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 108 | ext4_lblk_t needed; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 109 | |
| 110 | needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); |
| 111 | |
| 112 | /* Give ourselves just enough room to cope with inodes in which |
| 113 | * i_blocks is corrupt: we've seen disk corruptions in the past |
| 114 | * which resulted in random data in an inode which looked enough |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 115 | * like a regular file for ext4 to try to delete it. Things |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 116 | * will go a bit crazy if that happens, but at least we should |
| 117 | * try not to panic the whole kernel. */ |
| 118 | if (needed < 2) |
| 119 | needed = 2; |
| 120 | |
| 121 | /* But we need to bound the transaction so we don't overflow the |
| 122 | * journal. */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 123 | if (needed > EXT4_MAX_TRANS_DATA) |
| 124 | needed = EXT4_MAX_TRANS_DATA; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 125 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 126 | return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 127 | } |
| 128 | |
| 129 | /* |
| 130 | * Truncate transactions can be complex and absolutely huge. So we need to |
| 131 | * be able to restart the transaction at a conventient checkpoint to make |
| 132 | * sure we don't overflow the journal. |
| 133 | * |
| 134 | * start_transaction gets us a new handle for a truncate transaction, |
| 135 | * and extend_transaction tries to extend the existing one a bit. If |
| 136 | * extend fails, we need to propagate the failure up and restart the |
| 137 | * transaction in the top-level truncate loop. --sct |
| 138 | */ |
| 139 | static handle_t *start_transaction(struct inode *inode) |
| 140 | { |
| 141 | handle_t *result; |
| 142 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 143 | result = ext4_journal_start(inode, blocks_for_truncate(inode)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 144 | if (!IS_ERR(result)) |
| 145 | return result; |
| 146 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 147 | ext4_std_error(inode->i_sb, PTR_ERR(result)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 148 | return result; |
| 149 | } |
| 150 | |
| 151 | /* |
| 152 | * Try to extend this transaction for the purposes of truncation. |
| 153 | * |
| 154 | * Returns 0 if we managed to create more room. If we can't create more |
| 155 | * room, and the transaction must be restarted we return 1. |
| 156 | */ |
| 157 | static int try_to_extend_transaction(handle_t *handle, struct inode *inode) |
| 158 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 159 | if (handle->h_buffer_credits > EXT4_RESERVE_TRANS_BLOCKS) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 160 | return 0; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 161 | if (!ext4_journal_extend(handle, blocks_for_truncate(inode))) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 162 | return 0; |
| 163 | return 1; |
| 164 | } |
| 165 | |
| 166 | /* |
| 167 | * Restart the transaction associated with *handle. This does a commit, |
| 168 | * so before we call here everything must be consistently dirtied against |
| 169 | * this transaction. |
| 170 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 171 | static int ext4_journal_test_restart(handle_t *handle, struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 172 | { |
| 173 | jbd_debug(2, "restarting handle %p\n", handle); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 174 | return ext4_journal_restart(handle, blocks_for_truncate(inode)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 175 | } |
| 176 | |
| 177 | /* |
| 178 | * Called at the last iput() if i_nlink is zero. |
| 179 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 180 | void ext4_delete_inode (struct inode * inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 181 | { |
| 182 | handle_t *handle; |
| 183 | |
| 184 | truncate_inode_pages(&inode->i_data, 0); |
| 185 | |
| 186 | if (is_bad_inode(inode)) |
| 187 | goto no_delete; |
| 188 | |
| 189 | handle = start_transaction(inode); |
| 190 | if (IS_ERR(handle)) { |
| 191 | /* |
| 192 | * If we're going to skip the normal cleanup, we still need to |
| 193 | * make sure that the in-core orphan linked list is properly |
| 194 | * cleaned up. |
| 195 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 196 | ext4_orphan_del(NULL, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 197 | goto no_delete; |
| 198 | } |
| 199 | |
| 200 | if (IS_SYNC(inode)) |
| 201 | handle->h_sync = 1; |
| 202 | inode->i_size = 0; |
| 203 | if (inode->i_blocks) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 204 | ext4_truncate(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 205 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 206 | * Kill off the orphan record which ext4_truncate created. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 207 | * AKPM: I think this can be inside the above `if'. |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 208 | * Note that ext4_orphan_del() has to be able to cope with the |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 209 | * deletion of a non-existent orphan - this is because we don't |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 210 | * know if ext4_truncate() actually created an orphan record. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 211 | * (Well, we could do this if we need to, but heck - it works) |
| 212 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 213 | ext4_orphan_del(handle, inode); |
| 214 | EXT4_I(inode)->i_dtime = get_seconds(); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 215 | |
| 216 | /* |
| 217 | * One subtle ordering requirement: if anything has gone wrong |
| 218 | * (transaction abort, IO errors, whatever), then we can still |
| 219 | * do these next steps (the fs will already have been marked as |
| 220 | * having errors), but we can't free the inode if the mark_dirty |
| 221 | * fails. |
| 222 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 223 | if (ext4_mark_inode_dirty(handle, inode)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 224 | /* If that failed, just do the required in-core inode clear. */ |
| 225 | clear_inode(inode); |
| 226 | else |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 227 | ext4_free_inode(handle, inode); |
| 228 | ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 229 | return; |
| 230 | no_delete: |
| 231 | clear_inode(inode); /* We must guarantee clearing of inode... */ |
| 232 | } |
| 233 | |
| 234 | typedef struct { |
| 235 | __le32 *p; |
| 236 | __le32 key; |
| 237 | struct buffer_head *bh; |
| 238 | } Indirect; |
| 239 | |
| 240 | static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) |
| 241 | { |
| 242 | p->key = *(p->p = v); |
| 243 | p->bh = bh; |
| 244 | } |
| 245 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 246 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 247 | * ext4_block_to_path - parse the block number into array of offsets |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 248 | * @inode: inode in question (we are only interested in its superblock) |
| 249 | * @i_block: block number to be parsed |
| 250 | * @offsets: array to store the offsets in |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 251 | * @boundary: set this non-zero if the referred-to block is likely to be |
| 252 | * followed (on disk) by an indirect block. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 253 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 254 | * To store the locations of file's data ext4 uses a data structure common |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 255 | * for UNIX filesystems - tree of pointers anchored in the inode, with |
| 256 | * data blocks at leaves and indirect blocks in intermediate nodes. |
| 257 | * This function translates the block number into path in that tree - |
| 258 | * return value is the path length and @offsets[n] is the offset of |
| 259 | * pointer to (n+1)th node in the nth one. If @block is out of range |
| 260 | * (negative or too large) warning is printed and zero returned. |
| 261 | * |
| 262 | * Note: function doesn't find node addresses, so no IO is needed. All |
| 263 | * we need to know is the capacity of indirect blocks (taken from the |
| 264 | * inode->i_sb). |
| 265 | */ |
| 266 | |
| 267 | /* |
| 268 | * Portability note: the last comparison (check that we fit into triple |
| 269 | * indirect block) is spelled differently, because otherwise on an |
| 270 | * architecture with 32-bit longs and 8Kb pages we might get into trouble |
| 271 | * if our filesystem had 8Kb blocks. We might use long long, but that would |
| 272 | * kill us on x86. Oh, well, at least the sign propagation does not matter - |
| 273 | * i_block would have to be negative in the very beginning, so we would not |
| 274 | * get there at all. |
| 275 | */ |
| 276 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 277 | static int ext4_block_to_path(struct inode *inode, |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 278 | ext4_lblk_t i_block, |
| 279 | ext4_lblk_t offsets[4], int *boundary) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 280 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 281 | int ptrs = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
| 282 | int ptrs_bits = EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb); |
| 283 | const long direct_blocks = EXT4_NDIR_BLOCKS, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 284 | indirect_blocks = ptrs, |
| 285 | double_blocks = (1 << (ptrs_bits * 2)); |
| 286 | int n = 0; |
| 287 | int final = 0; |
| 288 | |
| 289 | if (i_block < 0) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 290 | ext4_warning (inode->i_sb, "ext4_block_to_path", "block < 0"); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 291 | } else if (i_block < direct_blocks) { |
| 292 | offsets[n++] = i_block; |
| 293 | final = direct_blocks; |
| 294 | } else if ( (i_block -= direct_blocks) < indirect_blocks) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 295 | offsets[n++] = EXT4_IND_BLOCK; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 296 | offsets[n++] = i_block; |
| 297 | final = ptrs; |
| 298 | } else if ((i_block -= indirect_blocks) < double_blocks) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 299 | offsets[n++] = EXT4_DIND_BLOCK; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 300 | offsets[n++] = i_block >> ptrs_bits; |
| 301 | offsets[n++] = i_block & (ptrs - 1); |
| 302 | final = ptrs; |
| 303 | } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 304 | offsets[n++] = EXT4_TIND_BLOCK; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 305 | offsets[n++] = i_block >> (ptrs_bits * 2); |
| 306 | offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); |
| 307 | offsets[n++] = i_block & (ptrs - 1); |
| 308 | final = ptrs; |
| 309 | } else { |
Eric Sandeen | e2b4657 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 310 | ext4_warning(inode->i_sb, "ext4_block_to_path", |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 311 | "block %lu > max", |
Eric Sandeen | e2b4657 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 312 | i_block + direct_blocks + |
| 313 | indirect_blocks + double_blocks); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 314 | } |
| 315 | if (boundary) |
| 316 | *boundary = final - 1 - (i_block & (ptrs - 1)); |
| 317 | return n; |
| 318 | } |
| 319 | |
| 320 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 321 | * ext4_get_branch - read the chain of indirect blocks leading to data |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 322 | * @inode: inode in question |
| 323 | * @depth: depth of the chain (1 - direct pointer, etc.) |
| 324 | * @offsets: offsets of pointers in inode/indirect blocks |
| 325 | * @chain: place to store the result |
| 326 | * @err: here we store the error value |
| 327 | * |
| 328 | * Function fills the array of triples <key, p, bh> and returns %NULL |
| 329 | * if everything went OK or the pointer to the last filled triple |
| 330 | * (incomplete one) otherwise. Upon the return chain[i].key contains |
| 331 | * the number of (i+1)-th block in the chain (as it is stored in memory, |
| 332 | * i.e. little-endian 32-bit), chain[i].p contains the address of that |
| 333 | * number (it points into struct inode for i==0 and into the bh->b_data |
| 334 | * for i>0) and chain[i].bh points to the buffer_head of i-th indirect |
| 335 | * block for i>0 and NULL for i==0. In other words, it holds the block |
| 336 | * numbers of the chain, addresses they were taken from (and where we can |
| 337 | * verify that chain did not change) and buffer_heads hosting these |
| 338 | * numbers. |
| 339 | * |
| 340 | * Function stops when it stumbles upon zero pointer (absent block) |
| 341 | * (pointer to last triple returned, *@err == 0) |
| 342 | * or when it gets an IO error reading an indirect block |
| 343 | * (ditto, *@err == -EIO) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 344 | * or when it reads all @depth-1 indirect blocks successfully and finds |
| 345 | * the whole chain, all way to the data (returns %NULL, *err == 0). |
Aneesh Kumar K.V | c278bfe | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 346 | * |
| 347 | * Need to be called with |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 348 | * down_read(&EXT4_I(inode)->i_data_sem) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 349 | */ |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 350 | static Indirect *ext4_get_branch(struct inode *inode, int depth, |
| 351 | ext4_lblk_t *offsets, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 352 | Indirect chain[4], int *err) |
| 353 | { |
| 354 | struct super_block *sb = inode->i_sb; |
| 355 | Indirect *p = chain; |
| 356 | struct buffer_head *bh; |
| 357 | |
| 358 | *err = 0; |
| 359 | /* i_data is not going away, no lock needed */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 360 | add_chain (chain, NULL, EXT4_I(inode)->i_data + *offsets); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 361 | if (!p->key) |
| 362 | goto no_block; |
| 363 | while (--depth) { |
| 364 | bh = sb_bread(sb, le32_to_cpu(p->key)); |
| 365 | if (!bh) |
| 366 | goto failure; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 367 | add_chain(++p, bh, (__le32*)bh->b_data + *++offsets); |
| 368 | /* Reader: end */ |
| 369 | if (!p->key) |
| 370 | goto no_block; |
| 371 | } |
| 372 | return NULL; |
| 373 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 374 | failure: |
| 375 | *err = -EIO; |
| 376 | no_block: |
| 377 | return p; |
| 378 | } |
| 379 | |
| 380 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 381 | * ext4_find_near - find a place for allocation with sufficient locality |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 382 | * @inode: owner |
| 383 | * @ind: descriptor of indirect block. |
| 384 | * |
| 385 | * This function returns the prefered place for block allocation. |
| 386 | * It is used when heuristic for sequential allocation fails. |
| 387 | * Rules are: |
| 388 | * + if there is a block to the left of our position - allocate near it. |
| 389 | * + if pointer will live in indirect block - allocate near that block. |
| 390 | * + if pointer will live in inode - allocate in the same |
| 391 | * cylinder group. |
| 392 | * |
| 393 | * In the latter case we colour the starting block by the callers PID to |
| 394 | * prevent it from clashing with concurrent allocations for a different inode |
| 395 | * in the same block group. The PID is used here so that functionally related |
| 396 | * files will be close-by on-disk. |
| 397 | * |
| 398 | * Caller must make sure that @ind is valid and will stay that way. |
| 399 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 400 | static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 401 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 402 | struct ext4_inode_info *ei = EXT4_I(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 403 | __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data; |
| 404 | __le32 *p; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 405 | ext4_fsblk_t bg_start; |
| 406 | ext4_grpblk_t colour; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 407 | |
| 408 | /* Try to find previous block */ |
| 409 | for (p = ind->p - 1; p >= start; p--) { |
| 410 | if (*p) |
| 411 | return le32_to_cpu(*p); |
| 412 | } |
| 413 | |
| 414 | /* No such thing, so let's try location of indirect block */ |
| 415 | if (ind->bh) |
| 416 | return ind->bh->b_blocknr; |
| 417 | |
| 418 | /* |
| 419 | * It is going to be referred to from the inode itself? OK, just put it |
| 420 | * into the same cylinder group then. |
| 421 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 422 | bg_start = ext4_group_first_block_no(inode->i_sb, ei->i_block_group); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 423 | colour = (current->pid % 16) * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 424 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 425 | return bg_start + colour; |
| 426 | } |
| 427 | |
| 428 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 429 | * ext4_find_goal - find a prefered place for allocation. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 430 | * @inode: owner |
| 431 | * @block: block we want |
| 432 | * @chain: chain of indirect blocks |
| 433 | * @partial: pointer to the last triple within a chain |
| 434 | * @goal: place to store the result. |
| 435 | * |
| 436 | * Normally this function find the prefered place for block allocation, |
| 437 | * stores it in *@goal and returns zero. |
| 438 | */ |
| 439 | |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 440 | static ext4_fsblk_t ext4_find_goal(struct inode *inode, ext4_lblk_t block, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 441 | Indirect chain[4], Indirect *partial) |
| 442 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 443 | struct ext4_block_alloc_info *block_i; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 444 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 445 | block_i = EXT4_I(inode)->i_block_alloc_info; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 446 | |
| 447 | /* |
| 448 | * try the heuristic for sequential allocation, |
| 449 | * failing that at least try to get decent locality. |
| 450 | */ |
| 451 | if (block_i && (block == block_i->last_alloc_logical_block + 1) |
| 452 | && (block_i->last_alloc_physical_block != 0)) { |
| 453 | return block_i->last_alloc_physical_block + 1; |
| 454 | } |
| 455 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 456 | return ext4_find_near(inode, partial); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 457 | } |
| 458 | |
| 459 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 460 | * ext4_blks_to_allocate: Look up the block map and count the number |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 461 | * of direct blocks need to be allocated for the given branch. |
| 462 | * |
| 463 | * @branch: chain of indirect blocks |
| 464 | * @k: number of blocks need for indirect blocks |
| 465 | * @blks: number of data blocks to be mapped. |
| 466 | * @blocks_to_boundary: the offset in the indirect block |
| 467 | * |
| 468 | * return the total number of blocks to be allocate, including the |
| 469 | * direct and indirect blocks. |
| 470 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 471 | static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned long blks, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 472 | int blocks_to_boundary) |
| 473 | { |
| 474 | unsigned long count = 0; |
| 475 | |
| 476 | /* |
| 477 | * Simple case, [t,d]Indirect block(s) has not allocated yet |
| 478 | * then it's clear blocks on that path have not allocated |
| 479 | */ |
| 480 | if (k > 0) { |
| 481 | /* right now we don't handle cross boundary allocation */ |
| 482 | if (blks < blocks_to_boundary + 1) |
| 483 | count += blks; |
| 484 | else |
| 485 | count += blocks_to_boundary + 1; |
| 486 | return count; |
| 487 | } |
| 488 | |
| 489 | count++; |
| 490 | while (count < blks && count <= blocks_to_boundary && |
| 491 | le32_to_cpu(*(branch[0].p + count)) == 0) { |
| 492 | count++; |
| 493 | } |
| 494 | return count; |
| 495 | } |
| 496 | |
| 497 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 498 | * ext4_alloc_blocks: multiple allocate blocks needed for a branch |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 499 | * @indirect_blks: the number of blocks need to allocate for indirect |
| 500 | * blocks |
| 501 | * |
| 502 | * @new_blocks: on return it will store the new block numbers for |
| 503 | * the indirect blocks(if needed) and the first direct block, |
| 504 | * @blks: on return it will store the total number of allocated |
| 505 | * direct blocks |
| 506 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 507 | static int ext4_alloc_blocks(handle_t *handle, struct inode *inode, |
| 508 | ext4_fsblk_t goal, int indirect_blks, int blks, |
| 509 | ext4_fsblk_t new_blocks[4], int *err) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 510 | { |
| 511 | int target, i; |
| 512 | unsigned long count = 0; |
| 513 | int index = 0; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 514 | ext4_fsblk_t current_block = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 515 | int ret = 0; |
| 516 | |
| 517 | /* |
| 518 | * Here we try to allocate the requested multiple blocks at once, |
| 519 | * on a best-effort basis. |
| 520 | * To build a branch, we should allocate blocks for |
| 521 | * the indirect blocks(if not allocated yet), and at least |
| 522 | * the first direct block of this branch. That's the |
| 523 | * minimum number of blocks need to allocate(required) |
| 524 | */ |
| 525 | target = blks + indirect_blks; |
| 526 | |
| 527 | while (1) { |
| 528 | count = target; |
| 529 | /* allocating blocks for indirect blocks and direct blocks */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 530 | current_block = ext4_new_blocks(handle,inode,goal,&count,err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 531 | if (*err) |
| 532 | goto failed_out; |
| 533 | |
| 534 | target -= count; |
| 535 | /* allocate blocks for indirect blocks */ |
| 536 | while (index < indirect_blks && count) { |
| 537 | new_blocks[index++] = current_block++; |
| 538 | count--; |
| 539 | } |
| 540 | |
| 541 | if (count > 0) |
| 542 | break; |
| 543 | } |
| 544 | |
| 545 | /* save the new block number for the first direct block */ |
| 546 | new_blocks[index] = current_block; |
| 547 | |
| 548 | /* total number of blocks allocated for direct blocks */ |
| 549 | ret = count; |
| 550 | *err = 0; |
| 551 | return ret; |
| 552 | failed_out: |
| 553 | for (i = 0; i <index; i++) |
Alex Tomas | c9de560 | 2008-01-29 00:19:52 -0500 | [diff] [blame] | 554 | ext4_free_blocks(handle, inode, new_blocks[i], 1, 0); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 555 | return ret; |
| 556 | } |
| 557 | |
| 558 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 559 | * ext4_alloc_branch - allocate and set up a chain of blocks. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 560 | * @inode: owner |
| 561 | * @indirect_blks: number of allocated indirect blocks |
| 562 | * @blks: number of allocated direct blocks |
| 563 | * @offsets: offsets (in the blocks) to store the pointers to next. |
| 564 | * @branch: place to store the chain in. |
| 565 | * |
| 566 | * This function allocates blocks, zeroes out all but the last one, |
| 567 | * links them into chain and (if we are synchronous) writes them to disk. |
| 568 | * In other words, it prepares a branch that can be spliced onto the |
| 569 | * inode. It stores the information about that chain in the branch[], in |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 570 | * the same format as ext4_get_branch() would do. We are calling it after |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 571 | * we had read the existing part of chain and partial points to the last |
| 572 | * triple of that (one with zero ->key). Upon the exit we have the same |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 573 | * picture as after the successful ext4_get_block(), except that in one |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 574 | * place chain is disconnected - *branch->p is still zero (we did not |
| 575 | * set the last link), but branch->key contains the number that should |
| 576 | * be placed into *branch->p to fill that gap. |
| 577 | * |
| 578 | * If allocation fails we free all blocks we've allocated (and forget |
| 579 | * their buffer_heads) and return the error value the from failed |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 580 | * ext4_alloc_block() (normally -ENOSPC). Otherwise we set the chain |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 581 | * as described above and return 0. |
| 582 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 583 | static int ext4_alloc_branch(handle_t *handle, struct inode *inode, |
| 584 | int indirect_blks, int *blks, ext4_fsblk_t goal, |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 585 | ext4_lblk_t *offsets, Indirect *branch) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 586 | { |
| 587 | int blocksize = inode->i_sb->s_blocksize; |
| 588 | int i, n = 0; |
| 589 | int err = 0; |
| 590 | struct buffer_head *bh; |
| 591 | int num; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 592 | ext4_fsblk_t new_blocks[4]; |
| 593 | ext4_fsblk_t current_block; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 594 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 595 | num = ext4_alloc_blocks(handle, inode, goal, indirect_blks, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 596 | *blks, new_blocks, &err); |
| 597 | if (err) |
| 598 | return err; |
| 599 | |
| 600 | branch[0].key = cpu_to_le32(new_blocks[0]); |
| 601 | /* |
| 602 | * metadata blocks and data blocks are allocated. |
| 603 | */ |
| 604 | for (n = 1; n <= indirect_blks; n++) { |
| 605 | /* |
| 606 | * Get buffer_head for parent block, zero it out |
| 607 | * and set the pointer to new one, then send |
| 608 | * parent to disk. |
| 609 | */ |
| 610 | bh = sb_getblk(inode->i_sb, new_blocks[n-1]); |
| 611 | branch[n].bh = bh; |
| 612 | lock_buffer(bh); |
| 613 | BUFFER_TRACE(bh, "call get_create_access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 614 | err = ext4_journal_get_create_access(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 615 | if (err) { |
| 616 | unlock_buffer(bh); |
| 617 | brelse(bh); |
| 618 | goto failed; |
| 619 | } |
| 620 | |
| 621 | memset(bh->b_data, 0, blocksize); |
| 622 | branch[n].p = (__le32 *) bh->b_data + offsets[n]; |
| 623 | branch[n].key = cpu_to_le32(new_blocks[n]); |
| 624 | *branch[n].p = branch[n].key; |
| 625 | if ( n == indirect_blks) { |
| 626 | current_block = new_blocks[n]; |
| 627 | /* |
| 628 | * End of chain, update the last new metablock of |
| 629 | * the chain to point to the new allocated |
| 630 | * data blocks numbers |
| 631 | */ |
| 632 | for (i=1; i < num; i++) |
| 633 | *(branch[n].p + i) = cpu_to_le32(++current_block); |
| 634 | } |
| 635 | BUFFER_TRACE(bh, "marking uptodate"); |
| 636 | set_buffer_uptodate(bh); |
| 637 | unlock_buffer(bh); |
| 638 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 639 | BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata"); |
| 640 | err = ext4_journal_dirty_metadata(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 641 | if (err) |
| 642 | goto failed; |
| 643 | } |
| 644 | *blks = num; |
| 645 | return err; |
| 646 | failed: |
| 647 | /* Allocation failed, free what we already allocated */ |
| 648 | for (i = 1; i <= n ; i++) { |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 649 | BUFFER_TRACE(branch[i].bh, "call jbd2_journal_forget"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 650 | ext4_journal_forget(handle, branch[i].bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 651 | } |
| 652 | for (i = 0; i <indirect_blks; i++) |
Alex Tomas | c9de560 | 2008-01-29 00:19:52 -0500 | [diff] [blame] | 653 | ext4_free_blocks(handle, inode, new_blocks[i], 1, 0); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 654 | |
Alex Tomas | c9de560 | 2008-01-29 00:19:52 -0500 | [diff] [blame] | 655 | ext4_free_blocks(handle, inode, new_blocks[i], num, 0); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 656 | |
| 657 | return err; |
| 658 | } |
| 659 | |
| 660 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 661 | * ext4_splice_branch - splice the allocated branch onto inode. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 662 | * @inode: owner |
| 663 | * @block: (logical) number of block we are adding |
| 664 | * @chain: chain of indirect blocks (with a missing link - see |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 665 | * ext4_alloc_branch) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 666 | * @where: location of missing link |
| 667 | * @num: number of indirect blocks we are adding |
| 668 | * @blks: number of direct blocks we are adding |
| 669 | * |
| 670 | * This function fills the missing link and does all housekeeping needed in |
| 671 | * inode (->i_blocks, etc.). In case of success we end up with the full |
| 672 | * chain to new block and return 0. |
| 673 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 674 | static int ext4_splice_branch(handle_t *handle, struct inode *inode, |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 675 | ext4_lblk_t block, Indirect *where, int num, int blks) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 676 | { |
| 677 | int i; |
| 678 | int err = 0; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 679 | struct ext4_block_alloc_info *block_i; |
| 680 | ext4_fsblk_t current_block; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 681 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 682 | block_i = EXT4_I(inode)->i_block_alloc_info; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 683 | /* |
| 684 | * If we're splicing into a [td]indirect block (as opposed to the |
| 685 | * inode) then we need to get write access to the [td]indirect block |
| 686 | * before the splice. |
| 687 | */ |
| 688 | if (where->bh) { |
| 689 | BUFFER_TRACE(where->bh, "get_write_access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 690 | err = ext4_journal_get_write_access(handle, where->bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 691 | if (err) |
| 692 | goto err_out; |
| 693 | } |
| 694 | /* That's it */ |
| 695 | |
| 696 | *where->p = where->key; |
| 697 | |
| 698 | /* |
| 699 | * Update the host buffer_head or inode to point to more just allocated |
| 700 | * direct blocks blocks |
| 701 | */ |
| 702 | if (num == 0 && blks > 1) { |
| 703 | current_block = le32_to_cpu(where->key) + 1; |
| 704 | for (i = 1; i < blks; i++) |
| 705 | *(where->p + i ) = cpu_to_le32(current_block++); |
| 706 | } |
| 707 | |
| 708 | /* |
| 709 | * update the most recently allocated logical & physical block |
| 710 | * in i_block_alloc_info, to assist find the proper goal block for next |
| 711 | * allocation |
| 712 | */ |
| 713 | if (block_i) { |
| 714 | block_i->last_alloc_logical_block = block + blks - 1; |
| 715 | block_i->last_alloc_physical_block = |
| 716 | le32_to_cpu(where[num].key) + blks - 1; |
| 717 | } |
| 718 | |
| 719 | /* We are done with atomic stuff, now do the rest of housekeeping */ |
| 720 | |
Kalpak Shah | ef7f383 | 2007-07-18 09:15:20 -0400 | [diff] [blame] | 721 | inode->i_ctime = ext4_current_time(inode); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 722 | ext4_mark_inode_dirty(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 723 | |
| 724 | /* had we spliced it onto indirect block? */ |
| 725 | if (where->bh) { |
| 726 | /* |
| 727 | * If we spliced it onto an indirect block, we haven't |
| 728 | * altered the inode. Note however that if it is being spliced |
| 729 | * onto an indirect block at the very end of the file (the |
| 730 | * file is growing) then we *will* alter the inode to reflect |
| 731 | * the new i_size. But that is not done here - it is done in |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 732 | * generic_commit_write->__mark_inode_dirty->ext4_dirty_inode. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 733 | */ |
| 734 | jbd_debug(5, "splicing indirect only\n"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 735 | BUFFER_TRACE(where->bh, "call ext4_journal_dirty_metadata"); |
| 736 | err = ext4_journal_dirty_metadata(handle, where->bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 737 | if (err) |
| 738 | goto err_out; |
| 739 | } else { |
| 740 | /* |
| 741 | * OK, we spliced it into the inode itself on a direct block. |
| 742 | * Inode was dirtied above. |
| 743 | */ |
| 744 | jbd_debug(5, "splicing direct\n"); |
| 745 | } |
| 746 | return err; |
| 747 | |
| 748 | err_out: |
| 749 | for (i = 1; i <= num; i++) { |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 750 | BUFFER_TRACE(where[i].bh, "call jbd2_journal_forget"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 751 | ext4_journal_forget(handle, where[i].bh); |
Alex Tomas | c9de560 | 2008-01-29 00:19:52 -0500 | [diff] [blame] | 752 | ext4_free_blocks(handle, inode, |
| 753 | le32_to_cpu(where[i-1].key), 1, 0); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 754 | } |
Alex Tomas | c9de560 | 2008-01-29 00:19:52 -0500 | [diff] [blame] | 755 | ext4_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks, 0); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 756 | |
| 757 | return err; |
| 758 | } |
| 759 | |
| 760 | /* |
| 761 | * Allocation strategy is simple: if we have to allocate something, we will |
| 762 | * have to go the whole way to leaf. So let's do it before attaching anything |
| 763 | * to tree, set linkage between the newborn blocks, write them if sync is |
| 764 | * required, recheck the path, free and repeat if check fails, otherwise |
| 765 | * set the last missing link (that will protect us from any truncate-generated |
| 766 | * removals - all blocks on the path are immune now) and possibly force the |
| 767 | * write on the parent block. |
| 768 | * That has a nice additional property: no special recovery from the failed |
| 769 | * allocations is needed - we simply release blocks and do not touch anything |
| 770 | * reachable from inode. |
| 771 | * |
| 772 | * `handle' can be NULL if create == 0. |
| 773 | * |
| 774 | * The BKL may not be held on entry here. Be sure to take it early. |
| 775 | * return > 0, # of blocks mapped or allocated. |
| 776 | * return = 0, if plain lookup failed. |
| 777 | * return < 0, error case. |
Aneesh Kumar K.V | c278bfe | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 778 | * |
| 779 | * |
| 780 | * Need to be called with |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 781 | * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block |
| 782 | * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 783 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 784 | int ext4_get_blocks_handle(handle_t *handle, struct inode *inode, |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 785 | ext4_lblk_t iblock, unsigned long maxblocks, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 786 | struct buffer_head *bh_result, |
| 787 | int create, int extend_disksize) |
| 788 | { |
| 789 | int err = -EIO; |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 790 | ext4_lblk_t offsets[4]; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 791 | Indirect chain[4]; |
| 792 | Indirect *partial; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 793 | ext4_fsblk_t goal; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 794 | int indirect_blks; |
| 795 | int blocks_to_boundary = 0; |
| 796 | int depth; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 797 | struct ext4_inode_info *ei = EXT4_I(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 798 | int count = 0; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 799 | ext4_fsblk_t first_block = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 800 | |
| 801 | |
Alex Tomas | a86c618 | 2006-10-11 01:21:03 -0700 | [diff] [blame] | 802 | J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 803 | J_ASSERT(handle != NULL || create == 0); |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 804 | depth = ext4_block_to_path(inode, iblock, offsets, |
| 805 | &blocks_to_boundary); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 806 | |
| 807 | if (depth == 0) |
| 808 | goto out; |
| 809 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 810 | partial = ext4_get_branch(inode, depth, offsets, chain, &err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 811 | |
| 812 | /* Simplest case - block found, no allocation needed */ |
| 813 | if (!partial) { |
| 814 | first_block = le32_to_cpu(chain[depth - 1].key); |
| 815 | clear_buffer_new(bh_result); |
| 816 | count++; |
| 817 | /*map more blocks*/ |
| 818 | while (count < maxblocks && count <= blocks_to_boundary) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 819 | ext4_fsblk_t blk; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 820 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 821 | blk = le32_to_cpu(*(chain[depth-1].p + count)); |
| 822 | |
| 823 | if (blk == first_block + count) |
| 824 | count++; |
| 825 | else |
| 826 | break; |
| 827 | } |
Aneesh Kumar K.V | c278bfe | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 828 | goto got_it; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 829 | } |
| 830 | |
| 831 | /* Next simple case - plain lookup or failed read of indirect block */ |
| 832 | if (!create || err == -EIO) |
| 833 | goto cleanup; |
| 834 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 835 | /* |
| 836 | * Okay, we need to do block allocation. Lazily initialize the block |
| 837 | * allocation info here if necessary |
| 838 | */ |
| 839 | if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info)) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 840 | ext4_init_block_alloc_info(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 841 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 842 | goal = ext4_find_goal(inode, iblock, chain, partial); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 843 | |
| 844 | /* the number of blocks need to allocate for [d,t]indirect blocks */ |
| 845 | indirect_blks = (chain + depth) - partial - 1; |
| 846 | |
| 847 | /* |
| 848 | * Next look up the indirect map to count the totoal number of |
| 849 | * direct blocks to allocate for this branch. |
| 850 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 851 | count = ext4_blks_to_allocate(partial, indirect_blks, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 852 | maxblocks, blocks_to_boundary); |
| 853 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 854 | * Block out ext4_truncate while we alter the tree |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 855 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 856 | err = ext4_alloc_branch(handle, inode, indirect_blks, &count, goal, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 857 | offsets + (partial - chain), partial); |
| 858 | |
| 859 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 860 | * The ext4_splice_branch call will free and forget any buffers |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 861 | * on the new chain if there is a failure, but that risks using |
| 862 | * up transaction credits, especially for bitmaps where the |
| 863 | * credits cannot be returned. Can we handle this somehow? We |
| 864 | * may need to return -EAGAIN upwards in the worst case. --sct |
| 865 | */ |
| 866 | if (!err) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 867 | err = ext4_splice_branch(handle, inode, iblock, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 868 | partial, indirect_blks, count); |
| 869 | /* |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 870 | * i_disksize growing is protected by i_data_sem. Don't forget to |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 871 | * protect it if you're about to implement concurrent |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 872 | * ext4_get_block() -bzzz |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 873 | */ |
| 874 | if (!err && extend_disksize && inode->i_size > ei->i_disksize) |
| 875 | ei->i_disksize = inode->i_size; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 876 | if (err) |
| 877 | goto cleanup; |
| 878 | |
| 879 | set_buffer_new(bh_result); |
| 880 | got_it: |
| 881 | map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); |
| 882 | if (count > blocks_to_boundary) |
| 883 | set_buffer_boundary(bh_result); |
| 884 | err = count; |
| 885 | /* Clean up and exit */ |
| 886 | partial = chain + depth - 1; /* the whole chain */ |
| 887 | cleanup: |
| 888 | while (partial > chain) { |
| 889 | BUFFER_TRACE(partial->bh, "call brelse"); |
| 890 | brelse(partial->bh); |
| 891 | partial--; |
| 892 | } |
| 893 | BUFFER_TRACE(bh_result, "returned"); |
| 894 | out: |
| 895 | return err; |
| 896 | } |
| 897 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 898 | #define DIO_CREDITS (EXT4_RESERVE_TRANS_BLOCKS + 32) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 899 | |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 900 | int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block, |
| 901 | unsigned long max_blocks, struct buffer_head *bh, |
| 902 | int create, int extend_disksize) |
| 903 | { |
| 904 | int retval; |
Aneesh Kumar K.V | 4df3d26 | 2008-01-28 23:58:29 -0500 | [diff] [blame] | 905 | /* |
| 906 | * Try to see if we can get the block without requesting |
| 907 | * for new file system block. |
| 908 | */ |
| 909 | down_read((&EXT4_I(inode)->i_data_sem)); |
| 910 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
| 911 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, |
| 912 | bh, 0, 0); |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 913 | } else { |
Aneesh Kumar K.V | 4df3d26 | 2008-01-28 23:58:29 -0500 | [diff] [blame] | 914 | retval = ext4_get_blocks_handle(handle, |
| 915 | inode, block, max_blocks, bh, 0, 0); |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 916 | } |
Aneesh Kumar K.V | 4df3d26 | 2008-01-28 23:58:29 -0500 | [diff] [blame] | 917 | up_read((&EXT4_I(inode)->i_data_sem)); |
| 918 | if (!create || (retval > 0)) |
| 919 | return retval; |
| 920 | |
| 921 | /* |
| 922 | * We need to allocate new blocks which will result |
| 923 | * in i_data update |
| 924 | */ |
| 925 | down_write((&EXT4_I(inode)->i_data_sem)); |
| 926 | /* |
| 927 | * We need to check for EXT4 here because migrate |
| 928 | * could have changed the inode type in between |
| 929 | */ |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 930 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
| 931 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, |
| 932 | bh, create, extend_disksize); |
| 933 | } else { |
| 934 | retval = ext4_get_blocks_handle(handle, inode, block, |
| 935 | max_blocks, bh, create, extend_disksize); |
| 936 | } |
Aneesh Kumar K.V | 4df3d26 | 2008-01-28 23:58:29 -0500 | [diff] [blame] | 937 | up_write((&EXT4_I(inode)->i_data_sem)); |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 938 | return retval; |
| 939 | } |
| 940 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 941 | static int ext4_get_block(struct inode *inode, sector_t iblock, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 942 | struct buffer_head *bh_result, int create) |
| 943 | { |
Dmitriy Monakhov | 3e4fdaf | 2007-02-10 01:46:35 -0800 | [diff] [blame] | 944 | handle_t *handle = ext4_journal_current_handle(); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 945 | int ret = 0; |
| 946 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; |
| 947 | |
| 948 | if (!create) |
| 949 | goto get_block; /* A read */ |
| 950 | |
| 951 | if (max_blocks == 1) |
| 952 | goto get_block; /* A single block get */ |
| 953 | |
| 954 | if (handle->h_transaction->t_state == T_LOCKED) { |
| 955 | /* |
| 956 | * Huge direct-io writes can hold off commits for long |
| 957 | * periods of time. Let this commit run. |
| 958 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 959 | ext4_journal_stop(handle); |
| 960 | handle = ext4_journal_start(inode, DIO_CREDITS); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 961 | if (IS_ERR(handle)) |
| 962 | ret = PTR_ERR(handle); |
| 963 | goto get_block; |
| 964 | } |
| 965 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 966 | if (handle->h_buffer_credits <= EXT4_RESERVE_TRANS_BLOCKS) { |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 967 | /* |
| 968 | * Getting low on buffer credits... |
| 969 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 970 | ret = ext4_journal_extend(handle, DIO_CREDITS); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 971 | if (ret > 0) { |
| 972 | /* |
| 973 | * Couldn't extend the transaction. Start a new one. |
| 974 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 975 | ret = ext4_journal_restart(handle, DIO_CREDITS); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 976 | } |
| 977 | } |
| 978 | |
| 979 | get_block: |
| 980 | if (ret == 0) { |
Alex Tomas | a86c618 | 2006-10-11 01:21:03 -0700 | [diff] [blame] | 981 | ret = ext4_get_blocks_wrap(handle, inode, iblock, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 982 | max_blocks, bh_result, create, 0); |
| 983 | if (ret > 0) { |
| 984 | bh_result->b_size = (ret << inode->i_blkbits); |
| 985 | ret = 0; |
| 986 | } |
| 987 | } |
| 988 | return ret; |
| 989 | } |
| 990 | |
| 991 | /* |
| 992 | * `handle' can be NULL if create is zero |
| 993 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 994 | struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 995 | ext4_lblk_t block, int create, int *errp) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 996 | { |
| 997 | struct buffer_head dummy; |
| 998 | int fatal = 0, err; |
| 999 | |
| 1000 | J_ASSERT(handle != NULL || create == 0); |
| 1001 | |
| 1002 | dummy.b_state = 0; |
| 1003 | dummy.b_blocknr = -1000; |
| 1004 | buffer_trace_init(&dummy.b_history); |
Alex Tomas | a86c618 | 2006-10-11 01:21:03 -0700 | [diff] [blame] | 1005 | err = ext4_get_blocks_wrap(handle, inode, block, 1, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1006 | &dummy, create, 1); |
| 1007 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1008 | * ext4_get_blocks_handle() returns number of blocks |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1009 | * mapped. 0 in case of a HOLE. |
| 1010 | */ |
| 1011 | if (err > 0) { |
| 1012 | if (err > 1) |
| 1013 | WARN_ON(1); |
| 1014 | err = 0; |
| 1015 | } |
| 1016 | *errp = err; |
| 1017 | if (!err && buffer_mapped(&dummy)) { |
| 1018 | struct buffer_head *bh; |
| 1019 | bh = sb_getblk(inode->i_sb, dummy.b_blocknr); |
| 1020 | if (!bh) { |
| 1021 | *errp = -EIO; |
| 1022 | goto err; |
| 1023 | } |
| 1024 | if (buffer_new(&dummy)) { |
| 1025 | J_ASSERT(create != 0); |
Aneesh Kumar K.V | ac39849 | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 1026 | J_ASSERT(handle != NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1027 | |
| 1028 | /* |
| 1029 | * Now that we do not always journal data, we should |
| 1030 | * keep in mind whether this should always journal the |
| 1031 | * new buffer as metadata. For now, regular file |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1032 | * writes use ext4_get_block instead, so it's not a |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1033 | * problem. |
| 1034 | */ |
| 1035 | lock_buffer(bh); |
| 1036 | BUFFER_TRACE(bh, "call get_create_access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1037 | fatal = ext4_journal_get_create_access(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1038 | if (!fatal && !buffer_uptodate(bh)) { |
| 1039 | memset(bh->b_data,0,inode->i_sb->s_blocksize); |
| 1040 | set_buffer_uptodate(bh); |
| 1041 | } |
| 1042 | unlock_buffer(bh); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1043 | BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata"); |
| 1044 | err = ext4_journal_dirty_metadata(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1045 | if (!fatal) |
| 1046 | fatal = err; |
| 1047 | } else { |
| 1048 | BUFFER_TRACE(bh, "not a new buffer"); |
| 1049 | } |
| 1050 | if (fatal) { |
| 1051 | *errp = fatal; |
| 1052 | brelse(bh); |
| 1053 | bh = NULL; |
| 1054 | } |
| 1055 | return bh; |
| 1056 | } |
| 1057 | err: |
| 1058 | return NULL; |
| 1059 | } |
| 1060 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1061 | struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode, |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 1062 | ext4_lblk_t block, int create, int *err) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1063 | { |
| 1064 | struct buffer_head * bh; |
| 1065 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1066 | bh = ext4_getblk(handle, inode, block, create, err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1067 | if (!bh) |
| 1068 | return bh; |
| 1069 | if (buffer_uptodate(bh)) |
| 1070 | return bh; |
| 1071 | ll_rw_block(READ_META, 1, &bh); |
| 1072 | wait_on_buffer(bh); |
| 1073 | if (buffer_uptodate(bh)) |
| 1074 | return bh; |
| 1075 | put_bh(bh); |
| 1076 | *err = -EIO; |
| 1077 | return NULL; |
| 1078 | } |
| 1079 | |
| 1080 | static int walk_page_buffers( handle_t *handle, |
| 1081 | struct buffer_head *head, |
| 1082 | unsigned from, |
| 1083 | unsigned to, |
| 1084 | int *partial, |
| 1085 | int (*fn)( handle_t *handle, |
| 1086 | struct buffer_head *bh)) |
| 1087 | { |
| 1088 | struct buffer_head *bh; |
| 1089 | unsigned block_start, block_end; |
| 1090 | unsigned blocksize = head->b_size; |
| 1091 | int err, ret = 0; |
| 1092 | struct buffer_head *next; |
| 1093 | |
| 1094 | for ( bh = head, block_start = 0; |
| 1095 | ret == 0 && (bh != head || !block_start); |
| 1096 | block_start = block_end, bh = next) |
| 1097 | { |
| 1098 | next = bh->b_this_page; |
| 1099 | block_end = block_start + blocksize; |
| 1100 | if (block_end <= from || block_start >= to) { |
| 1101 | if (partial && !buffer_uptodate(bh)) |
| 1102 | *partial = 1; |
| 1103 | continue; |
| 1104 | } |
| 1105 | err = (*fn)(handle, bh); |
| 1106 | if (!ret) |
| 1107 | ret = err; |
| 1108 | } |
| 1109 | return ret; |
| 1110 | } |
| 1111 | |
| 1112 | /* |
| 1113 | * To preserve ordering, it is essential that the hole instantiation and |
| 1114 | * the data write be encapsulated in a single transaction. We cannot |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1115 | * close off a transaction and start a new one between the ext4_get_block() |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 1116 | * and the commit_write(). So doing the jbd2_journal_start at the start of |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1117 | * prepare_write() is the right place. |
| 1118 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1119 | * Also, this function can nest inside ext4_writepage() -> |
| 1120 | * block_write_full_page(). In that case, we *know* that ext4_writepage() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1121 | * has generated enough buffer credits to do the whole page. So we won't |
| 1122 | * block on the journal in that case, which is good, because the caller may |
| 1123 | * be PF_MEMALLOC. |
| 1124 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1125 | * By accident, ext4 can be reentered when a transaction is open via |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1126 | * quota file writes. If we were to commit the transaction while thus |
| 1127 | * reentered, there can be a deadlock - we would be holding a quota |
| 1128 | * lock, and the commit would never complete if another thread had a |
| 1129 | * transaction open and was blocking on the quota lock - a ranking |
| 1130 | * violation. |
| 1131 | * |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 1132 | * So what we do is to rely on the fact that jbd2_journal_stop/journal_start |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1133 | * will _not_ run commit under these circumstances because handle->h_ref |
| 1134 | * is elevated. We'll still have enough credits for the tiny quotafile |
| 1135 | * write. |
| 1136 | */ |
| 1137 | static int do_journal_get_write_access(handle_t *handle, |
| 1138 | struct buffer_head *bh) |
| 1139 | { |
| 1140 | if (!buffer_mapped(bh) || buffer_freed(bh)) |
| 1141 | return 0; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1142 | return ext4_journal_get_write_access(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1143 | } |
| 1144 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1145 | static int ext4_write_begin(struct file *file, struct address_space *mapping, |
| 1146 | loff_t pos, unsigned len, unsigned flags, |
| 1147 | struct page **pagep, void **fsdata) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1148 | { |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1149 | struct inode *inode = mapping->host; |
Andrew Morton | 7479d2b | 2007-04-01 23:49:44 -0700 | [diff] [blame] | 1150 | int ret, needed_blocks = ext4_writepage_trans_blocks(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1151 | handle_t *handle; |
| 1152 | int retries = 0; |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1153 | struct page *page; |
| 1154 | pgoff_t index; |
| 1155 | unsigned from, to; |
| 1156 | |
| 1157 | index = pos >> PAGE_CACHE_SHIFT; |
| 1158 | from = pos & (PAGE_CACHE_SIZE - 1); |
| 1159 | to = from + len; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1160 | |
| 1161 | retry: |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1162 | page = __grab_cache_page(mapping, index); |
| 1163 | if (!page) |
| 1164 | return -ENOMEM; |
| 1165 | *pagep = page; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1166 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1167 | handle = ext4_journal_start(inode, needed_blocks); |
| 1168 | if (IS_ERR(handle)) { |
| 1169 | unlock_page(page); |
| 1170 | page_cache_release(page); |
| 1171 | ret = PTR_ERR(handle); |
| 1172 | goto out; |
| 1173 | } |
| 1174 | |
| 1175 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, |
| 1176 | ext4_get_block); |
| 1177 | |
| 1178 | if (!ret && ext4_should_journal_data(inode)) { |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1179 | ret = walk_page_buffers(handle, page_buffers(page), |
| 1180 | from, to, NULL, do_journal_get_write_access); |
| 1181 | } |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1182 | |
| 1183 | if (ret) { |
Andrew Morton | 7479d2b | 2007-04-01 23:49:44 -0700 | [diff] [blame] | 1184 | ext4_journal_stop(handle); |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1185 | unlock_page(page); |
| 1186 | page_cache_release(page); |
| 1187 | } |
| 1188 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1189 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1190 | goto retry; |
Andrew Morton | 7479d2b | 2007-04-01 23:49:44 -0700 | [diff] [blame] | 1191 | out: |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1192 | return ret; |
| 1193 | } |
| 1194 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1195 | int ext4_journal_dirty_data(handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1196 | { |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 1197 | int err = jbd2_journal_dirty_data(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1198 | if (err) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1199 | ext4_journal_abort_handle(__FUNCTION__, __FUNCTION__, |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1200 | bh, handle, err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1201 | return err; |
| 1202 | } |
| 1203 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1204 | /* For write_end() in data=journal mode */ |
| 1205 | static int write_end_fn(handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1206 | { |
| 1207 | if (!buffer_mapped(bh) || buffer_freed(bh)) |
| 1208 | return 0; |
| 1209 | set_buffer_uptodate(bh); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1210 | return ext4_journal_dirty_metadata(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1211 | } |
| 1212 | |
| 1213 | /* |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1214 | * Generic write_end handler for ordered and writeback ext4 journal modes. |
| 1215 | * We can't use generic_write_end, because that unlocks the page and we need to |
| 1216 | * unlock the page after ext4_journal_stop, but ext4_journal_stop must run |
| 1217 | * after block_write_end. |
| 1218 | */ |
| 1219 | static int ext4_generic_write_end(struct file *file, |
| 1220 | struct address_space *mapping, |
| 1221 | loff_t pos, unsigned len, unsigned copied, |
| 1222 | struct page *page, void *fsdata) |
| 1223 | { |
| 1224 | struct inode *inode = file->f_mapping->host; |
| 1225 | |
| 1226 | copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); |
| 1227 | |
| 1228 | if (pos+copied > inode->i_size) { |
| 1229 | i_size_write(inode, pos+copied); |
| 1230 | mark_inode_dirty(inode); |
| 1231 | } |
| 1232 | |
| 1233 | return copied; |
| 1234 | } |
| 1235 | |
| 1236 | /* |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1237 | * We need to pick up the new inode size which generic_commit_write gave us |
| 1238 | * `file' can be NULL - eg, when called from page_symlink(). |
| 1239 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1240 | * ext4 never places buffers on inode->i_mapping->private_list. metadata |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1241 | * buffers are managed internally. |
| 1242 | */ |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1243 | static int ext4_ordered_write_end(struct file *file, |
| 1244 | struct address_space *mapping, |
| 1245 | loff_t pos, unsigned len, unsigned copied, |
| 1246 | struct page *page, void *fsdata) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1247 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1248 | handle_t *handle = ext4_journal_current_handle(); |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1249 | struct inode *inode = file->f_mapping->host; |
| 1250 | unsigned from, to; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1251 | int ret = 0, ret2; |
| 1252 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1253 | from = pos & (PAGE_CACHE_SIZE - 1); |
| 1254 | to = from + len; |
| 1255 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1256 | ret = walk_page_buffers(handle, page_buffers(page), |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1257 | from, to, NULL, ext4_journal_dirty_data); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1258 | |
| 1259 | if (ret == 0) { |
| 1260 | /* |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1261 | * generic_write_end() will run mark_inode_dirty() if i_size |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1262 | * changes. So let's piggyback the i_disksize mark_inode_dirty |
| 1263 | * into that. |
| 1264 | */ |
| 1265 | loff_t new_i_size; |
| 1266 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1267 | new_i_size = pos + copied; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1268 | if (new_i_size > EXT4_I(inode)->i_disksize) |
| 1269 | EXT4_I(inode)->i_disksize = new_i_size; |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1270 | copied = ext4_generic_write_end(file, mapping, pos, len, copied, |
| 1271 | page, fsdata); |
| 1272 | if (copied < 0) |
| 1273 | ret = copied; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1274 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1275 | ret2 = ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1276 | if (!ret) |
| 1277 | ret = ret2; |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1278 | unlock_page(page); |
| 1279 | page_cache_release(page); |
| 1280 | |
| 1281 | return ret ? ret : copied; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1282 | } |
| 1283 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1284 | static int ext4_writeback_write_end(struct file *file, |
| 1285 | struct address_space *mapping, |
| 1286 | loff_t pos, unsigned len, unsigned copied, |
| 1287 | struct page *page, void *fsdata) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1288 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1289 | handle_t *handle = ext4_journal_current_handle(); |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1290 | struct inode *inode = file->f_mapping->host; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1291 | int ret = 0, ret2; |
| 1292 | loff_t new_i_size; |
| 1293 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1294 | new_i_size = pos + copied; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1295 | if (new_i_size > EXT4_I(inode)->i_disksize) |
| 1296 | EXT4_I(inode)->i_disksize = new_i_size; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1297 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1298 | copied = ext4_generic_write_end(file, mapping, pos, len, copied, |
| 1299 | page, fsdata); |
| 1300 | if (copied < 0) |
| 1301 | ret = copied; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1302 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1303 | ret2 = ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1304 | if (!ret) |
| 1305 | ret = ret2; |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1306 | unlock_page(page); |
| 1307 | page_cache_release(page); |
| 1308 | |
| 1309 | return ret ? ret : copied; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1310 | } |
| 1311 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1312 | static int ext4_journalled_write_end(struct file *file, |
| 1313 | struct address_space *mapping, |
| 1314 | loff_t pos, unsigned len, unsigned copied, |
| 1315 | struct page *page, void *fsdata) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1316 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1317 | handle_t *handle = ext4_journal_current_handle(); |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1318 | struct inode *inode = mapping->host; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1319 | int ret = 0, ret2; |
| 1320 | int partial = 0; |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1321 | unsigned from, to; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1322 | |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1323 | from = pos & (PAGE_CACHE_SIZE - 1); |
| 1324 | to = from + len; |
| 1325 | |
| 1326 | if (copied < len) { |
| 1327 | if (!PageUptodate(page)) |
| 1328 | copied = 0; |
| 1329 | page_zero_new_buffers(page, from+copied, to); |
| 1330 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1331 | |
| 1332 | ret = walk_page_buffers(handle, page_buffers(page), from, |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1333 | to, &partial, write_end_fn); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1334 | if (!partial) |
| 1335 | SetPageUptodate(page); |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1336 | if (pos+copied > inode->i_size) |
| 1337 | i_size_write(inode, pos+copied); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1338 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; |
| 1339 | if (inode->i_size > EXT4_I(inode)->i_disksize) { |
| 1340 | EXT4_I(inode)->i_disksize = inode->i_size; |
| 1341 | ret2 = ext4_mark_inode_dirty(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1342 | if (!ret) |
| 1343 | ret = ret2; |
| 1344 | } |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1345 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1346 | ret2 = ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1347 | if (!ret) |
| 1348 | ret = ret2; |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1349 | unlock_page(page); |
| 1350 | page_cache_release(page); |
| 1351 | |
| 1352 | return ret ? ret : copied; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1353 | } |
| 1354 | |
| 1355 | /* |
| 1356 | * bmap() is special. It gets used by applications such as lilo and by |
| 1357 | * the swapper to find the on-disk block of a specific piece of data. |
| 1358 | * |
| 1359 | * Naturally, this is dangerous if the block concerned is still in the |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1360 | * journal. If somebody makes a swapfile on an ext4 data-journaling |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1361 | * filesystem and enables swap, then they may get a nasty shock when the |
| 1362 | * data getting swapped to that swapfile suddenly gets overwritten by |
| 1363 | * the original zero's written out previously to the journal and |
| 1364 | * awaiting writeback in the kernel's buffer cache. |
| 1365 | * |
| 1366 | * So, if we see any bmap calls here on a modified, data-journaled file, |
| 1367 | * take extra steps to flush any blocks which might be in the cache. |
| 1368 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1369 | static sector_t ext4_bmap(struct address_space *mapping, sector_t block) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1370 | { |
| 1371 | struct inode *inode = mapping->host; |
| 1372 | journal_t *journal; |
| 1373 | int err; |
| 1374 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1375 | if (EXT4_I(inode)->i_state & EXT4_STATE_JDATA) { |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1376 | /* |
| 1377 | * This is a REALLY heavyweight approach, but the use of |
| 1378 | * bmap on dirty files is expected to be extremely rare: |
| 1379 | * only if we run lilo or swapon on a freshly made file |
| 1380 | * do we expect this to happen. |
| 1381 | * |
| 1382 | * (bmap requires CAP_SYS_RAWIO so this does not |
| 1383 | * represent an unprivileged user DOS attack --- we'd be |
| 1384 | * in trouble if mortal users could trigger this path at |
| 1385 | * will.) |
| 1386 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1387 | * NB. EXT4_STATE_JDATA is not set on files other than |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1388 | * regular files. If somebody wants to bmap a directory |
| 1389 | * or symlink and gets confused because the buffer |
| 1390 | * hasn't yet been flushed to disk, they deserve |
| 1391 | * everything they get. |
| 1392 | */ |
| 1393 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1394 | EXT4_I(inode)->i_state &= ~EXT4_STATE_JDATA; |
| 1395 | journal = EXT4_JOURNAL(inode); |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 1396 | jbd2_journal_lock_updates(journal); |
| 1397 | err = jbd2_journal_flush(journal); |
| 1398 | jbd2_journal_unlock_updates(journal); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1399 | |
| 1400 | if (err) |
| 1401 | return 0; |
| 1402 | } |
| 1403 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1404 | return generic_block_bmap(mapping,block,ext4_get_block); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1405 | } |
| 1406 | |
| 1407 | static int bget_one(handle_t *handle, struct buffer_head *bh) |
| 1408 | { |
| 1409 | get_bh(bh); |
| 1410 | return 0; |
| 1411 | } |
| 1412 | |
| 1413 | static int bput_one(handle_t *handle, struct buffer_head *bh) |
| 1414 | { |
| 1415 | put_bh(bh); |
| 1416 | return 0; |
| 1417 | } |
| 1418 | |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 1419 | static int jbd2_journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1420 | { |
| 1421 | if (buffer_mapped(bh)) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1422 | return ext4_journal_dirty_data(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1423 | return 0; |
| 1424 | } |
| 1425 | |
| 1426 | /* |
| 1427 | * Note that we always start a transaction even if we're not journalling |
| 1428 | * data. This is to preserve ordering: any hole instantiation within |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1429 | * __block_write_full_page -> ext4_get_block() should be journalled |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1430 | * along with the data so we don't crash and then get metadata which |
| 1431 | * refers to old data. |
| 1432 | * |
| 1433 | * In all journalling modes block_write_full_page() will start the I/O. |
| 1434 | * |
| 1435 | * Problem: |
| 1436 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1437 | * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() -> |
| 1438 | * ext4_writepage() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1439 | * |
| 1440 | * Similar for: |
| 1441 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1442 | * ext4_file_write() -> generic_file_write() -> __alloc_pages() -> ... |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1443 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1444 | * Same applies to ext4_get_block(). We will deadlock on various things like |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 1445 | * lock_journal and i_data_sem |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1446 | * |
| 1447 | * Setting PF_MEMALLOC here doesn't work - too many internal memory |
| 1448 | * allocations fail. |
| 1449 | * |
| 1450 | * 16May01: If we're reentered then journal_current_handle() will be |
| 1451 | * non-zero. We simply *return*. |
| 1452 | * |
| 1453 | * 1 July 2001: @@@ FIXME: |
| 1454 | * In journalled data mode, a data buffer may be metadata against the |
| 1455 | * current transaction. But the same file is part of a shared mapping |
| 1456 | * and someone does a writepage() on it. |
| 1457 | * |
| 1458 | * We will move the buffer onto the async_data list, but *after* it has |
| 1459 | * been dirtied. So there's a small window where we have dirty data on |
| 1460 | * BJ_Metadata. |
| 1461 | * |
| 1462 | * Note that this only applies to the last partial page in the file. The |
| 1463 | * bit which block_write_full_page() uses prepare/commit for. (That's |
| 1464 | * broken code anyway: it's wrong for msync()). |
| 1465 | * |
| 1466 | * It's a rare case: affects the final partial page, for journalled data |
| 1467 | * where the file is subject to bith write() and writepage() in the same |
| 1468 | * transction. To fix it we'll need a custom block_write_full_page(). |
| 1469 | * We'll probably need that anyway for journalling writepage() output. |
| 1470 | * |
| 1471 | * We don't honour synchronous mounts for writepage(). That would be |
| 1472 | * disastrous. Any write() or metadata operation will sync the fs for |
| 1473 | * us. |
| 1474 | * |
| 1475 | * AKPM2: if all the page's buffers are mapped to disk and !data=journal, |
| 1476 | * we don't need to open a transaction here. |
| 1477 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1478 | static int ext4_ordered_writepage(struct page *page, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1479 | struct writeback_control *wbc) |
| 1480 | { |
| 1481 | struct inode *inode = page->mapping->host; |
| 1482 | struct buffer_head *page_bufs; |
| 1483 | handle_t *handle = NULL; |
| 1484 | int ret = 0; |
| 1485 | int err; |
| 1486 | |
| 1487 | J_ASSERT(PageLocked(page)); |
| 1488 | |
| 1489 | /* |
| 1490 | * We give up here if we're reentered, because it might be for a |
| 1491 | * different filesystem. |
| 1492 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1493 | if (ext4_journal_current_handle()) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1494 | goto out_fail; |
| 1495 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1496 | handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1497 | |
| 1498 | if (IS_ERR(handle)) { |
| 1499 | ret = PTR_ERR(handle); |
| 1500 | goto out_fail; |
| 1501 | } |
| 1502 | |
| 1503 | if (!page_has_buffers(page)) { |
| 1504 | create_empty_buffers(page, inode->i_sb->s_blocksize, |
| 1505 | (1 << BH_Dirty)|(1 << BH_Uptodate)); |
| 1506 | } |
| 1507 | page_bufs = page_buffers(page); |
| 1508 | walk_page_buffers(handle, page_bufs, 0, |
| 1509 | PAGE_CACHE_SIZE, NULL, bget_one); |
| 1510 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1511 | ret = block_write_full_page(page, ext4_get_block, wbc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1512 | |
| 1513 | /* |
| 1514 | * The page can become unlocked at any point now, and |
| 1515 | * truncate can then come in and change things. So we |
| 1516 | * can't touch *page from now on. But *page_bufs is |
| 1517 | * safe due to elevated refcount. |
| 1518 | */ |
| 1519 | |
| 1520 | /* |
| 1521 | * And attach them to the current transaction. But only if |
| 1522 | * block_write_full_page() succeeded. Otherwise they are unmapped, |
| 1523 | * and generally junk. |
| 1524 | */ |
| 1525 | if (ret == 0) { |
| 1526 | err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE, |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 1527 | NULL, jbd2_journal_dirty_data_fn); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1528 | if (!ret) |
| 1529 | ret = err; |
| 1530 | } |
| 1531 | walk_page_buffers(handle, page_bufs, 0, |
| 1532 | PAGE_CACHE_SIZE, NULL, bput_one); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1533 | err = ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1534 | if (!ret) |
| 1535 | ret = err; |
| 1536 | return ret; |
| 1537 | |
| 1538 | out_fail: |
| 1539 | redirty_page_for_writepage(wbc, page); |
| 1540 | unlock_page(page); |
| 1541 | return ret; |
| 1542 | } |
| 1543 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1544 | static int ext4_writeback_writepage(struct page *page, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1545 | struct writeback_control *wbc) |
| 1546 | { |
| 1547 | struct inode *inode = page->mapping->host; |
| 1548 | handle_t *handle = NULL; |
| 1549 | int ret = 0; |
| 1550 | int err; |
| 1551 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1552 | if (ext4_journal_current_handle()) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1553 | goto out_fail; |
| 1554 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1555 | handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1556 | if (IS_ERR(handle)) { |
| 1557 | ret = PTR_ERR(handle); |
| 1558 | goto out_fail; |
| 1559 | } |
| 1560 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1561 | if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) |
| 1562 | ret = nobh_writepage(page, ext4_get_block, wbc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1563 | else |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1564 | ret = block_write_full_page(page, ext4_get_block, wbc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1565 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1566 | err = ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1567 | if (!ret) |
| 1568 | ret = err; |
| 1569 | return ret; |
| 1570 | |
| 1571 | out_fail: |
| 1572 | redirty_page_for_writepage(wbc, page); |
| 1573 | unlock_page(page); |
| 1574 | return ret; |
| 1575 | } |
| 1576 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1577 | static int ext4_journalled_writepage(struct page *page, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1578 | struct writeback_control *wbc) |
| 1579 | { |
| 1580 | struct inode *inode = page->mapping->host; |
| 1581 | handle_t *handle = NULL; |
| 1582 | int ret = 0; |
| 1583 | int err; |
| 1584 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1585 | if (ext4_journal_current_handle()) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1586 | goto no_write; |
| 1587 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1588 | handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1589 | if (IS_ERR(handle)) { |
| 1590 | ret = PTR_ERR(handle); |
| 1591 | goto no_write; |
| 1592 | } |
| 1593 | |
| 1594 | if (!page_has_buffers(page) || PageChecked(page)) { |
| 1595 | /* |
| 1596 | * It's mmapped pagecache. Add buffers and journal it. There |
| 1597 | * doesn't seem much point in redirtying the page here. |
| 1598 | */ |
| 1599 | ClearPageChecked(page); |
| 1600 | ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1601 | ext4_get_block); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1602 | if (ret != 0) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1603 | ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1604 | goto out_unlock; |
| 1605 | } |
| 1606 | ret = walk_page_buffers(handle, page_buffers(page), 0, |
| 1607 | PAGE_CACHE_SIZE, NULL, do_journal_get_write_access); |
| 1608 | |
| 1609 | err = walk_page_buffers(handle, page_buffers(page), 0, |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1610 | PAGE_CACHE_SIZE, NULL, write_end_fn); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1611 | if (ret == 0) |
| 1612 | ret = err; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1613 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1614 | unlock_page(page); |
| 1615 | } else { |
| 1616 | /* |
| 1617 | * It may be a page full of checkpoint-mode buffers. We don't |
| 1618 | * really know unless we go poke around in the buffer_heads. |
| 1619 | * But block_write_full_page will do the right thing. |
| 1620 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1621 | ret = block_write_full_page(page, ext4_get_block, wbc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1622 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1623 | err = ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1624 | if (!ret) |
| 1625 | ret = err; |
| 1626 | out: |
| 1627 | return ret; |
| 1628 | |
| 1629 | no_write: |
| 1630 | redirty_page_for_writepage(wbc, page); |
| 1631 | out_unlock: |
| 1632 | unlock_page(page); |
| 1633 | goto out; |
| 1634 | } |
| 1635 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1636 | static int ext4_readpage(struct file *file, struct page *page) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1637 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1638 | return mpage_readpage(page, ext4_get_block); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1639 | } |
| 1640 | |
| 1641 | static int |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1642 | ext4_readpages(struct file *file, struct address_space *mapping, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1643 | struct list_head *pages, unsigned nr_pages) |
| 1644 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1645 | return mpage_readpages(mapping, pages, nr_pages, ext4_get_block); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1646 | } |
| 1647 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1648 | static void ext4_invalidatepage(struct page *page, unsigned long offset) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1649 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1650 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1651 | |
| 1652 | /* |
| 1653 | * If it's a full truncate we just forget about the pending dirtying |
| 1654 | */ |
| 1655 | if (offset == 0) |
| 1656 | ClearPageChecked(page); |
| 1657 | |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 1658 | jbd2_journal_invalidatepage(journal, page, offset); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1659 | } |
| 1660 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1661 | static int ext4_releasepage(struct page *page, gfp_t wait) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1662 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1663 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1664 | |
| 1665 | WARN_ON(PageChecked(page)); |
| 1666 | if (!page_has_buffers(page)) |
| 1667 | return 0; |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 1668 | return jbd2_journal_try_to_free_buffers(journal, page, wait); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1669 | } |
| 1670 | |
| 1671 | /* |
| 1672 | * If the O_DIRECT write will extend the file then add this inode to the |
| 1673 | * orphan list. So recovery will truncate it back to the original size |
| 1674 | * if the machine crashes during the write. |
| 1675 | * |
| 1676 | * If the O_DIRECT write is intantiating holes inside i_size and the machine |
| 1677 | * crashes then stale disk data _may_ be exposed inside the file. |
| 1678 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1679 | static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1680 | const struct iovec *iov, loff_t offset, |
| 1681 | unsigned long nr_segs) |
| 1682 | { |
| 1683 | struct file *file = iocb->ki_filp; |
| 1684 | struct inode *inode = file->f_mapping->host; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1685 | struct ext4_inode_info *ei = EXT4_I(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1686 | handle_t *handle = NULL; |
| 1687 | ssize_t ret; |
| 1688 | int orphan = 0; |
| 1689 | size_t count = iov_length(iov, nr_segs); |
| 1690 | |
| 1691 | if (rw == WRITE) { |
| 1692 | loff_t final_size = offset + count; |
| 1693 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1694 | handle = ext4_journal_start(inode, DIO_CREDITS); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1695 | if (IS_ERR(handle)) { |
| 1696 | ret = PTR_ERR(handle); |
| 1697 | goto out; |
| 1698 | } |
| 1699 | if (final_size > inode->i_size) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1700 | ret = ext4_orphan_add(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1701 | if (ret) |
| 1702 | goto out_stop; |
| 1703 | orphan = 1; |
| 1704 | ei->i_disksize = inode->i_size; |
| 1705 | } |
| 1706 | } |
| 1707 | |
| 1708 | ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, |
| 1709 | offset, nr_segs, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1710 | ext4_get_block, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1711 | |
| 1712 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1713 | * Reacquire the handle: ext4_get_block() can restart the transaction |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1714 | */ |
Dmitriy Monakhov | 3e4fdaf | 2007-02-10 01:46:35 -0800 | [diff] [blame] | 1715 | handle = ext4_journal_current_handle(); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1716 | |
| 1717 | out_stop: |
| 1718 | if (handle) { |
| 1719 | int err; |
| 1720 | |
| 1721 | if (orphan && inode->i_nlink) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1722 | ext4_orphan_del(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1723 | if (orphan && ret > 0) { |
| 1724 | loff_t end = offset + ret; |
| 1725 | if (end > inode->i_size) { |
| 1726 | ei->i_disksize = end; |
| 1727 | i_size_write(inode, end); |
| 1728 | /* |
| 1729 | * We're going to return a positive `ret' |
| 1730 | * here due to non-zero-length I/O, so there's |
| 1731 | * no way of reporting error returns from |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1732 | * ext4_mark_inode_dirty() to userspace. So |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1733 | * ignore it. |
| 1734 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1735 | ext4_mark_inode_dirty(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1736 | } |
| 1737 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1738 | err = ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1739 | if (ret == 0) |
| 1740 | ret = err; |
| 1741 | } |
| 1742 | out: |
| 1743 | return ret; |
| 1744 | } |
| 1745 | |
| 1746 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1747 | * Pages can be marked dirty completely asynchronously from ext4's journalling |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1748 | * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do |
| 1749 | * much here because ->set_page_dirty is called under VFS locks. The page is |
| 1750 | * not necessarily locked. |
| 1751 | * |
| 1752 | * We cannot just dirty the page and leave attached buffers clean, because the |
| 1753 | * buffers' dirty state is "definitive". We cannot just set the buffers dirty |
| 1754 | * or jbddirty because all the journalling code will explode. |
| 1755 | * |
| 1756 | * So what we do is to mark the page "pending dirty" and next time writepage |
| 1757 | * is called, propagate that into the buffers appropriately. |
| 1758 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1759 | static int ext4_journalled_set_page_dirty(struct page *page) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1760 | { |
| 1761 | SetPageChecked(page); |
| 1762 | return __set_page_dirty_nobuffers(page); |
| 1763 | } |
| 1764 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1765 | static const struct address_space_operations ext4_ordered_aops = { |
| 1766 | .readpage = ext4_readpage, |
| 1767 | .readpages = ext4_readpages, |
| 1768 | .writepage = ext4_ordered_writepage, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1769 | .sync_page = block_sync_page, |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1770 | .write_begin = ext4_write_begin, |
| 1771 | .write_end = ext4_ordered_write_end, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1772 | .bmap = ext4_bmap, |
| 1773 | .invalidatepage = ext4_invalidatepage, |
| 1774 | .releasepage = ext4_releasepage, |
| 1775 | .direct_IO = ext4_direct_IO, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1776 | .migratepage = buffer_migrate_page, |
| 1777 | }; |
| 1778 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1779 | static const struct address_space_operations ext4_writeback_aops = { |
| 1780 | .readpage = ext4_readpage, |
| 1781 | .readpages = ext4_readpages, |
| 1782 | .writepage = ext4_writeback_writepage, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1783 | .sync_page = block_sync_page, |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1784 | .write_begin = ext4_write_begin, |
| 1785 | .write_end = ext4_writeback_write_end, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1786 | .bmap = ext4_bmap, |
| 1787 | .invalidatepage = ext4_invalidatepage, |
| 1788 | .releasepage = ext4_releasepage, |
| 1789 | .direct_IO = ext4_direct_IO, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1790 | .migratepage = buffer_migrate_page, |
| 1791 | }; |
| 1792 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1793 | static const struct address_space_operations ext4_journalled_aops = { |
| 1794 | .readpage = ext4_readpage, |
| 1795 | .readpages = ext4_readpages, |
| 1796 | .writepage = ext4_journalled_writepage, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1797 | .sync_page = block_sync_page, |
Nick Piggin | bfc1af6 | 2007-10-16 01:25:05 -0700 | [diff] [blame] | 1798 | .write_begin = ext4_write_begin, |
| 1799 | .write_end = ext4_journalled_write_end, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1800 | .set_page_dirty = ext4_journalled_set_page_dirty, |
| 1801 | .bmap = ext4_bmap, |
| 1802 | .invalidatepage = ext4_invalidatepage, |
| 1803 | .releasepage = ext4_releasepage, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1804 | }; |
| 1805 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1806 | void ext4_set_aops(struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1807 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1808 | if (ext4_should_order_data(inode)) |
| 1809 | inode->i_mapping->a_ops = &ext4_ordered_aops; |
| 1810 | else if (ext4_should_writeback_data(inode)) |
| 1811 | inode->i_mapping->a_ops = &ext4_writeback_aops; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1812 | else |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1813 | inode->i_mapping->a_ops = &ext4_journalled_aops; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1814 | } |
| 1815 | |
| 1816 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1817 | * ext4_block_truncate_page() zeroes out a mapping from file offset `from' |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1818 | * up to the end of the block which corresponds to `from'. |
| 1819 | * This required during truncate. We need to physically zero the tail end |
| 1820 | * of that block so it doesn't yield old data if the file is later grown. |
| 1821 | */ |
Alex Tomas | a86c618 | 2006-10-11 01:21:03 -0700 | [diff] [blame] | 1822 | int ext4_block_truncate_page(handle_t *handle, struct page *page, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1823 | struct address_space *mapping, loff_t from) |
| 1824 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1825 | ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1826 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 1827 | unsigned blocksize, length, pos; |
| 1828 | ext4_lblk_t iblock; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1829 | struct inode *inode = mapping->host; |
| 1830 | struct buffer_head *bh; |
| 1831 | int err = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1832 | |
| 1833 | blocksize = inode->i_sb->s_blocksize; |
| 1834 | length = blocksize - (offset & (blocksize - 1)); |
| 1835 | iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); |
| 1836 | |
| 1837 | /* |
| 1838 | * For "nobh" option, we can only work if we don't need to |
| 1839 | * read-in the page - otherwise we create buffers to do the IO. |
| 1840 | */ |
| 1841 | if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1842 | ext4_should_writeback_data(inode) && PageUptodate(page)) { |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 1843 | zero_user(page, offset, length); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1844 | set_page_dirty(page); |
| 1845 | goto unlock; |
| 1846 | } |
| 1847 | |
| 1848 | if (!page_has_buffers(page)) |
| 1849 | create_empty_buffers(page, blocksize, 0); |
| 1850 | |
| 1851 | /* Find the buffer that contains "offset" */ |
| 1852 | bh = page_buffers(page); |
| 1853 | pos = blocksize; |
| 1854 | while (offset >= pos) { |
| 1855 | bh = bh->b_this_page; |
| 1856 | iblock++; |
| 1857 | pos += blocksize; |
| 1858 | } |
| 1859 | |
| 1860 | err = 0; |
| 1861 | if (buffer_freed(bh)) { |
| 1862 | BUFFER_TRACE(bh, "freed: skip"); |
| 1863 | goto unlock; |
| 1864 | } |
| 1865 | |
| 1866 | if (!buffer_mapped(bh)) { |
| 1867 | BUFFER_TRACE(bh, "unmapped"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1868 | ext4_get_block(inode, iblock, bh, 0); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1869 | /* unmapped? It's a hole - nothing to do */ |
| 1870 | if (!buffer_mapped(bh)) { |
| 1871 | BUFFER_TRACE(bh, "still unmapped"); |
| 1872 | goto unlock; |
| 1873 | } |
| 1874 | } |
| 1875 | |
| 1876 | /* Ok, it's mapped. Make sure it's up-to-date */ |
| 1877 | if (PageUptodate(page)) |
| 1878 | set_buffer_uptodate(bh); |
| 1879 | |
| 1880 | if (!buffer_uptodate(bh)) { |
| 1881 | err = -EIO; |
| 1882 | ll_rw_block(READ, 1, &bh); |
| 1883 | wait_on_buffer(bh); |
| 1884 | /* Uhhuh. Read error. Complain and punt. */ |
| 1885 | if (!buffer_uptodate(bh)) |
| 1886 | goto unlock; |
| 1887 | } |
| 1888 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1889 | if (ext4_should_journal_data(inode)) { |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1890 | BUFFER_TRACE(bh, "get write access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1891 | err = ext4_journal_get_write_access(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1892 | if (err) |
| 1893 | goto unlock; |
| 1894 | } |
| 1895 | |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 1896 | zero_user(page, offset, length); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1897 | |
| 1898 | BUFFER_TRACE(bh, "zeroed end of block"); |
| 1899 | |
| 1900 | err = 0; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1901 | if (ext4_should_journal_data(inode)) { |
| 1902 | err = ext4_journal_dirty_metadata(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1903 | } else { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1904 | if (ext4_should_order_data(inode)) |
| 1905 | err = ext4_journal_dirty_data(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1906 | mark_buffer_dirty(bh); |
| 1907 | } |
| 1908 | |
| 1909 | unlock: |
| 1910 | unlock_page(page); |
| 1911 | page_cache_release(page); |
| 1912 | return err; |
| 1913 | } |
| 1914 | |
| 1915 | /* |
| 1916 | * Probably it should be a library function... search for first non-zero word |
| 1917 | * or memcmp with zero_page, whatever is better for particular architecture. |
| 1918 | * Linus? |
| 1919 | */ |
| 1920 | static inline int all_zeroes(__le32 *p, __le32 *q) |
| 1921 | { |
| 1922 | while (p < q) |
| 1923 | if (*p++) |
| 1924 | return 0; |
| 1925 | return 1; |
| 1926 | } |
| 1927 | |
| 1928 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1929 | * ext4_find_shared - find the indirect blocks for partial truncation. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1930 | * @inode: inode in question |
| 1931 | * @depth: depth of the affected branch |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1932 | * @offsets: offsets of pointers in that branch (see ext4_block_to_path) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1933 | * @chain: place to store the pointers to partial indirect blocks |
| 1934 | * @top: place to the (detached) top of branch |
| 1935 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1936 | * This is a helper function used by ext4_truncate(). |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1937 | * |
| 1938 | * When we do truncate() we may have to clean the ends of several |
| 1939 | * indirect blocks but leave the blocks themselves alive. Block is |
| 1940 | * partially truncated if some data below the new i_size is refered |
| 1941 | * from it (and it is on the path to the first completely truncated |
| 1942 | * data block, indeed). We have to free the top of that path along |
| 1943 | * with everything to the right of the path. Since no allocation |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1944 | * past the truncation point is possible until ext4_truncate() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1945 | * finishes, we may safely do the latter, but top of branch may |
| 1946 | * require special attention - pageout below the truncation point |
| 1947 | * might try to populate it. |
| 1948 | * |
| 1949 | * We atomically detach the top of branch from the tree, store the |
| 1950 | * block number of its root in *@top, pointers to buffer_heads of |
| 1951 | * partially truncated blocks - in @chain[].bh and pointers to |
| 1952 | * their last elements that should not be removed - in |
| 1953 | * @chain[].p. Return value is the pointer to last filled element |
| 1954 | * of @chain. |
| 1955 | * |
| 1956 | * The work left to caller to do the actual freeing of subtrees: |
| 1957 | * a) free the subtree starting from *@top |
| 1958 | * b) free the subtrees whose roots are stored in |
| 1959 | * (@chain[i].p+1 .. end of @chain[i].bh->b_data) |
| 1960 | * c) free the subtrees growing from the inode past the @chain[0]. |
| 1961 | * (no partially truncated stuff there). */ |
| 1962 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1963 | static Indirect *ext4_find_shared(struct inode *inode, int depth, |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 1964 | ext4_lblk_t offsets[4], Indirect chain[4], __le32 *top) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1965 | { |
| 1966 | Indirect *partial, *p; |
| 1967 | int k, err; |
| 1968 | |
| 1969 | *top = 0; |
| 1970 | /* Make k index the deepest non-null offest + 1 */ |
| 1971 | for (k = depth; k > 1 && !offsets[k-1]; k--) |
| 1972 | ; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1973 | partial = ext4_get_branch(inode, k, offsets, chain, &err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1974 | /* Writer: pointers */ |
| 1975 | if (!partial) |
| 1976 | partial = chain + k-1; |
| 1977 | /* |
| 1978 | * If the branch acquired continuation since we've looked at it - |
| 1979 | * fine, it should all survive and (new) top doesn't belong to us. |
| 1980 | */ |
| 1981 | if (!partial->key && *partial->p) |
| 1982 | /* Writer: end */ |
| 1983 | goto no_top; |
| 1984 | for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--) |
| 1985 | ; |
| 1986 | /* |
| 1987 | * OK, we've found the last block that must survive. The rest of our |
| 1988 | * branch should be detached before unlocking. However, if that rest |
| 1989 | * of branch is all ours and does not grow immediately from the inode |
| 1990 | * it's easier to cheat and just decrement partial->p. |
| 1991 | */ |
| 1992 | if (p == chain + k - 1 && p > chain) { |
| 1993 | p->p--; |
| 1994 | } else { |
| 1995 | *top = *p->p; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 1996 | /* Nope, don't do this in ext4. Must leave the tree intact */ |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1997 | #if 0 |
| 1998 | *p->p = 0; |
| 1999 | #endif |
| 2000 | } |
| 2001 | /* Writer: end */ |
| 2002 | |
| 2003 | while(partial > p) { |
| 2004 | brelse(partial->bh); |
| 2005 | partial--; |
| 2006 | } |
| 2007 | no_top: |
| 2008 | return partial; |
| 2009 | } |
| 2010 | |
| 2011 | /* |
| 2012 | * Zero a number of block pointers in either an inode or an indirect block. |
| 2013 | * If we restart the transaction we must again get write access to the |
| 2014 | * indirect block for further modification. |
| 2015 | * |
| 2016 | * We release `count' blocks on disk, but (last - first) may be greater |
| 2017 | * than `count' because there can be holes in there. |
| 2018 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2019 | static void ext4_clear_blocks(handle_t *handle, struct inode *inode, |
| 2020 | struct buffer_head *bh, ext4_fsblk_t block_to_free, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2021 | unsigned long count, __le32 *first, __le32 *last) |
| 2022 | { |
| 2023 | __le32 *p; |
| 2024 | if (try_to_extend_transaction(handle, inode)) { |
| 2025 | if (bh) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2026 | BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata"); |
| 2027 | ext4_journal_dirty_metadata(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2028 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2029 | ext4_mark_inode_dirty(handle, inode); |
| 2030 | ext4_journal_test_restart(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2031 | if (bh) { |
| 2032 | BUFFER_TRACE(bh, "retaking write access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2033 | ext4_journal_get_write_access(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2034 | } |
| 2035 | } |
| 2036 | |
| 2037 | /* |
| 2038 | * Any buffers which are on the journal will be in memory. We find |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 2039 | * them on the hash table so jbd2_journal_revoke() will run jbd2_journal_forget() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2040 | * on them. We've already detached each block from the file, so |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 2041 | * bforget() in jbd2_journal_forget() should be safe. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2042 | * |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 2043 | * AKPM: turn on bforget in jbd2_journal_forget()!!! |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2044 | */ |
| 2045 | for (p = first; p < last; p++) { |
| 2046 | u32 nr = le32_to_cpu(*p); |
| 2047 | if (nr) { |
Aneesh Kumar K.V | 1d03ec9 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2048 | struct buffer_head *tbh; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2049 | |
| 2050 | *p = 0; |
Aneesh Kumar K.V | 1d03ec9 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2051 | tbh = sb_find_get_block(inode->i_sb, nr); |
| 2052 | ext4_forget(handle, 0, inode, tbh, nr); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2053 | } |
| 2054 | } |
| 2055 | |
Alex Tomas | c9de560 | 2008-01-29 00:19:52 -0500 | [diff] [blame] | 2056 | ext4_free_blocks(handle, inode, block_to_free, count, 0); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2057 | } |
| 2058 | |
| 2059 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2060 | * ext4_free_data - free a list of data blocks |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2061 | * @handle: handle for this transaction |
| 2062 | * @inode: inode we are dealing with |
| 2063 | * @this_bh: indirect buffer_head which contains *@first and *@last |
| 2064 | * @first: array of block numbers |
| 2065 | * @last: points immediately past the end of array |
| 2066 | * |
| 2067 | * We are freeing all blocks refered from that array (numbers are stored as |
| 2068 | * little-endian 32-bit) and updating @inode->i_blocks appropriately. |
| 2069 | * |
| 2070 | * We accumulate contiguous runs of blocks to free. Conveniently, if these |
| 2071 | * blocks are contiguous then releasing them at one time will only affect one |
| 2072 | * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't |
| 2073 | * actually use a lot of journal space. |
| 2074 | * |
| 2075 | * @this_bh will be %NULL if @first and @last point into the inode's direct |
| 2076 | * block pointers. |
| 2077 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2078 | static void ext4_free_data(handle_t *handle, struct inode *inode, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2079 | struct buffer_head *this_bh, |
| 2080 | __le32 *first, __le32 *last) |
| 2081 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2082 | ext4_fsblk_t block_to_free = 0; /* Starting block # of a run */ |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2083 | unsigned long count = 0; /* Number of blocks in the run */ |
| 2084 | __le32 *block_to_free_p = NULL; /* Pointer into inode/ind |
| 2085 | corresponding to |
| 2086 | block_to_free */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2087 | ext4_fsblk_t nr; /* Current block # */ |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2088 | __le32 *p; /* Pointer into inode/ind |
| 2089 | for current block */ |
| 2090 | int err; |
| 2091 | |
| 2092 | if (this_bh) { /* For indirect block */ |
| 2093 | BUFFER_TRACE(this_bh, "get_write_access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2094 | err = ext4_journal_get_write_access(handle, this_bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2095 | /* Important: if we can't update the indirect pointers |
| 2096 | * to the blocks, we can't free them. */ |
| 2097 | if (err) |
| 2098 | return; |
| 2099 | } |
| 2100 | |
| 2101 | for (p = first; p < last; p++) { |
| 2102 | nr = le32_to_cpu(*p); |
| 2103 | if (nr) { |
| 2104 | /* accumulate blocks to free if they're contiguous */ |
| 2105 | if (count == 0) { |
| 2106 | block_to_free = nr; |
| 2107 | block_to_free_p = p; |
| 2108 | count = 1; |
| 2109 | } else if (nr == block_to_free + count) { |
| 2110 | count++; |
| 2111 | } else { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2112 | ext4_clear_blocks(handle, inode, this_bh, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2113 | block_to_free, |
| 2114 | count, block_to_free_p, p); |
| 2115 | block_to_free = nr; |
| 2116 | block_to_free_p = p; |
| 2117 | count = 1; |
| 2118 | } |
| 2119 | } |
| 2120 | } |
| 2121 | |
| 2122 | if (count > 0) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2123 | ext4_clear_blocks(handle, inode, this_bh, block_to_free, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2124 | count, block_to_free_p, p); |
| 2125 | |
| 2126 | if (this_bh) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2127 | BUFFER_TRACE(this_bh, "call ext4_journal_dirty_metadata"); |
| 2128 | ext4_journal_dirty_metadata(handle, this_bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2129 | } |
| 2130 | } |
| 2131 | |
| 2132 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2133 | * ext4_free_branches - free an array of branches |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2134 | * @handle: JBD handle for this transaction |
| 2135 | * @inode: inode we are dealing with |
| 2136 | * @parent_bh: the buffer_head which contains *@first and *@last |
| 2137 | * @first: array of block numbers |
| 2138 | * @last: pointer immediately past the end of array |
| 2139 | * @depth: depth of the branches to free |
| 2140 | * |
| 2141 | * We are freeing all blocks refered from these branches (numbers are |
| 2142 | * stored as little-endian 32-bit) and updating @inode->i_blocks |
| 2143 | * appropriately. |
| 2144 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2145 | static void ext4_free_branches(handle_t *handle, struct inode *inode, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2146 | struct buffer_head *parent_bh, |
| 2147 | __le32 *first, __le32 *last, int depth) |
| 2148 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2149 | ext4_fsblk_t nr; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2150 | __le32 *p; |
| 2151 | |
| 2152 | if (is_handle_aborted(handle)) |
| 2153 | return; |
| 2154 | |
| 2155 | if (depth--) { |
| 2156 | struct buffer_head *bh; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2157 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2158 | p = last; |
| 2159 | while (--p >= first) { |
| 2160 | nr = le32_to_cpu(*p); |
| 2161 | if (!nr) |
| 2162 | continue; /* A hole */ |
| 2163 | |
| 2164 | /* Go read the buffer for the next level down */ |
| 2165 | bh = sb_bread(inode->i_sb, nr); |
| 2166 | |
| 2167 | /* |
| 2168 | * A read failure? Report error and clear slot |
| 2169 | * (should be rare). |
| 2170 | */ |
| 2171 | if (!bh) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2172 | ext4_error(inode->i_sb, "ext4_free_branches", |
Mingming Cao | 2ae0210 | 2006-10-11 01:21:11 -0700 | [diff] [blame] | 2173 | "Read failure, inode=%lu, block=%llu", |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2174 | inode->i_ino, nr); |
| 2175 | continue; |
| 2176 | } |
| 2177 | |
| 2178 | /* This zaps the entire block. Bottom up. */ |
| 2179 | BUFFER_TRACE(bh, "free child branches"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2180 | ext4_free_branches(handle, inode, bh, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2181 | (__le32*)bh->b_data, |
| 2182 | (__le32*)bh->b_data + addr_per_block, |
| 2183 | depth); |
| 2184 | |
| 2185 | /* |
| 2186 | * We've probably journalled the indirect block several |
| 2187 | * times during the truncate. But it's no longer |
| 2188 | * needed and we now drop it from the transaction via |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 2189 | * jbd2_journal_revoke(). |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2190 | * |
| 2191 | * That's easy if it's exclusively part of this |
| 2192 | * transaction. But if it's part of the committing |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 2193 | * transaction then jbd2_journal_forget() will simply |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2194 | * brelse() it. That means that if the underlying |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2195 | * block is reallocated in ext4_get_block(), |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2196 | * unmap_underlying_metadata() will find this block |
| 2197 | * and will try to get rid of it. damn, damn. |
| 2198 | * |
| 2199 | * If this block has already been committed to the |
| 2200 | * journal, a revoke record will be written. And |
| 2201 | * revoke records must be emitted *before* clearing |
| 2202 | * this block's bit in the bitmaps. |
| 2203 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2204 | ext4_forget(handle, 1, inode, bh, bh->b_blocknr); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2205 | |
| 2206 | /* |
| 2207 | * Everything below this this pointer has been |
| 2208 | * released. Now let this top-of-subtree go. |
| 2209 | * |
| 2210 | * We want the freeing of this indirect block to be |
| 2211 | * atomic in the journal with the updating of the |
| 2212 | * bitmap block which owns it. So make some room in |
| 2213 | * the journal. |
| 2214 | * |
| 2215 | * We zero the parent pointer *after* freeing its |
| 2216 | * pointee in the bitmaps, so if extend_transaction() |
| 2217 | * for some reason fails to put the bitmap changes and |
| 2218 | * the release into the same transaction, recovery |
| 2219 | * will merely complain about releasing a free block, |
| 2220 | * rather than leaking blocks. |
| 2221 | */ |
| 2222 | if (is_handle_aborted(handle)) |
| 2223 | return; |
| 2224 | if (try_to_extend_transaction(handle, inode)) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2225 | ext4_mark_inode_dirty(handle, inode); |
| 2226 | ext4_journal_test_restart(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2227 | } |
| 2228 | |
Alex Tomas | c9de560 | 2008-01-29 00:19:52 -0500 | [diff] [blame] | 2229 | ext4_free_blocks(handle, inode, nr, 1, 1); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2230 | |
| 2231 | if (parent_bh) { |
| 2232 | /* |
| 2233 | * The block which we have just freed is |
| 2234 | * pointed to by an indirect block: journal it |
| 2235 | */ |
| 2236 | BUFFER_TRACE(parent_bh, "get_write_access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2237 | if (!ext4_journal_get_write_access(handle, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2238 | parent_bh)){ |
| 2239 | *p = 0; |
| 2240 | BUFFER_TRACE(parent_bh, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2241 | "call ext4_journal_dirty_metadata"); |
| 2242 | ext4_journal_dirty_metadata(handle, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2243 | parent_bh); |
| 2244 | } |
| 2245 | } |
| 2246 | } |
| 2247 | } else { |
| 2248 | /* We have reached the bottom of the tree. */ |
| 2249 | BUFFER_TRACE(parent_bh, "free data blocks"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2250 | ext4_free_data(handle, inode, parent_bh, first, last); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2251 | } |
| 2252 | } |
| 2253 | |
| 2254 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2255 | * ext4_truncate() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2256 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2257 | * We block out ext4_get_block() block instantiations across the entire |
| 2258 | * transaction, and VFS/VM ensures that ext4_truncate() cannot run |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2259 | * simultaneously on behalf of the same inode. |
| 2260 | * |
| 2261 | * As we work through the truncate and commmit bits of it to the journal there |
| 2262 | * is one core, guiding principle: the file's tree must always be consistent on |
| 2263 | * disk. We must be able to restart the truncate after a crash. |
| 2264 | * |
| 2265 | * The file's tree may be transiently inconsistent in memory (although it |
| 2266 | * probably isn't), but whenever we close off and commit a journal transaction, |
| 2267 | * the contents of (the filesystem + the journal) must be consistent and |
| 2268 | * restartable. It's pretty simple, really: bottom up, right to left (although |
| 2269 | * left-to-right works OK too). |
| 2270 | * |
| 2271 | * Note that at recovery time, journal replay occurs *before* the restart of |
| 2272 | * truncate against the orphan inode list. |
| 2273 | * |
| 2274 | * The committed inode has the new, desired i_size (which is the same as |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2275 | * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2276 | * that this inode's truncate did not complete and it will again call |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2277 | * ext4_truncate() to have another go. So there will be instantiated blocks |
| 2278 | * to the right of the truncation point in a crashed ext4 filesystem. But |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2279 | * that's fine - as long as they are linked from the inode, the post-crash |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2280 | * ext4_truncate() run will find them and release them. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2281 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2282 | void ext4_truncate(struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2283 | { |
| 2284 | handle_t *handle; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2285 | struct ext4_inode_info *ei = EXT4_I(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2286 | __le32 *i_data = ei->i_data; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2287 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2288 | struct address_space *mapping = inode->i_mapping; |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2289 | ext4_lblk_t offsets[4]; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2290 | Indirect chain[4]; |
| 2291 | Indirect *partial; |
| 2292 | __le32 nr = 0; |
| 2293 | int n; |
Aneesh Kumar K.V | 725d26d | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2294 | ext4_lblk_t last_block; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2295 | unsigned blocksize = inode->i_sb->s_blocksize; |
| 2296 | struct page *page; |
| 2297 | |
| 2298 | if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
| 2299 | S_ISLNK(inode->i_mode))) |
| 2300 | return; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2301 | if (ext4_inode_is_fast_symlink(inode)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2302 | return; |
| 2303 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) |
| 2304 | return; |
| 2305 | |
| 2306 | /* |
| 2307 | * We have to lock the EOF page here, because lock_page() nests |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 2308 | * outside jbd2_journal_start(). |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2309 | */ |
| 2310 | if ((inode->i_size & (blocksize - 1)) == 0) { |
| 2311 | /* Block boundary? Nothing to do */ |
| 2312 | page = NULL; |
| 2313 | } else { |
| 2314 | page = grab_cache_page(mapping, |
| 2315 | inode->i_size >> PAGE_CACHE_SHIFT); |
| 2316 | if (!page) |
| 2317 | return; |
| 2318 | } |
| 2319 | |
Aneesh Kumar K.V | 1d03ec9 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2320 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
| 2321 | ext4_ext_truncate(inode, page); |
| 2322 | return; |
| 2323 | } |
Alex Tomas | a86c618 | 2006-10-11 01:21:03 -0700 | [diff] [blame] | 2324 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2325 | handle = start_transaction(inode); |
| 2326 | if (IS_ERR(handle)) { |
| 2327 | if (page) { |
| 2328 | clear_highpage(page); |
| 2329 | flush_dcache_page(page); |
| 2330 | unlock_page(page); |
| 2331 | page_cache_release(page); |
| 2332 | } |
| 2333 | return; /* AKPM: return what? */ |
| 2334 | } |
| 2335 | |
| 2336 | last_block = (inode->i_size + blocksize-1) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2337 | >> EXT4_BLOCK_SIZE_BITS(inode->i_sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2338 | |
| 2339 | if (page) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2340 | ext4_block_truncate_page(handle, page, mapping, inode->i_size); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2341 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2342 | n = ext4_block_to_path(inode, last_block, offsets, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2343 | if (n == 0) |
| 2344 | goto out_stop; /* error */ |
| 2345 | |
| 2346 | /* |
| 2347 | * OK. This truncate is going to happen. We add the inode to the |
| 2348 | * orphan list, so that if this truncate spans multiple transactions, |
| 2349 | * and we crash, we will resume the truncate when the filesystem |
| 2350 | * recovers. It also marks the inode dirty, to catch the new size. |
| 2351 | * |
| 2352 | * Implication: the file must always be in a sane, consistent |
| 2353 | * truncatable state while each transaction commits. |
| 2354 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2355 | if (ext4_orphan_add(handle, inode)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2356 | goto out_stop; |
| 2357 | |
| 2358 | /* |
| 2359 | * The orphan list entry will now protect us from any crash which |
| 2360 | * occurs before the truncate completes, so it is now safe to propagate |
| 2361 | * the new, shorter inode size (held for now in i_size) into the |
| 2362 | * on-disk inode. We do this via i_disksize, which is the value which |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2363 | * ext4 *really* writes onto the disk inode. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2364 | */ |
| 2365 | ei->i_disksize = inode->i_size; |
| 2366 | |
| 2367 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2368 | * From here we block out all ext4_get_block() callers who want to |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2369 | * modify the block allocation tree. |
| 2370 | */ |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2371 | down_write(&ei->i_data_sem); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2372 | |
| 2373 | if (n == 1) { /* direct blocks */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2374 | ext4_free_data(handle, inode, NULL, i_data+offsets[0], |
| 2375 | i_data + EXT4_NDIR_BLOCKS); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2376 | goto do_indirects; |
| 2377 | } |
| 2378 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2379 | partial = ext4_find_shared(inode, n, offsets, chain, &nr); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2380 | /* Kill the top of shared branch (not detached) */ |
| 2381 | if (nr) { |
| 2382 | if (partial == chain) { |
| 2383 | /* Shared branch grows from the inode */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2384 | ext4_free_branches(handle, inode, NULL, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2385 | &nr, &nr+1, (chain+n-1) - partial); |
| 2386 | *partial->p = 0; |
| 2387 | /* |
| 2388 | * We mark the inode dirty prior to restart, |
| 2389 | * and prior to stop. No need for it here. |
| 2390 | */ |
| 2391 | } else { |
| 2392 | /* Shared branch grows from an indirect block */ |
| 2393 | BUFFER_TRACE(partial->bh, "get_write_access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2394 | ext4_free_branches(handle, inode, partial->bh, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2395 | partial->p, |
| 2396 | partial->p+1, (chain+n-1) - partial); |
| 2397 | } |
| 2398 | } |
| 2399 | /* Clear the ends of indirect blocks on the shared branch */ |
| 2400 | while (partial > chain) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2401 | ext4_free_branches(handle, inode, partial->bh, partial->p + 1, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2402 | (__le32*)partial->bh->b_data+addr_per_block, |
| 2403 | (chain+n-1) - partial); |
| 2404 | BUFFER_TRACE(partial->bh, "call brelse"); |
| 2405 | brelse (partial->bh); |
| 2406 | partial--; |
| 2407 | } |
| 2408 | do_indirects: |
| 2409 | /* Kill the remaining (whole) subtrees */ |
| 2410 | switch (offsets[0]) { |
| 2411 | default: |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2412 | nr = i_data[EXT4_IND_BLOCK]; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2413 | if (nr) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2414 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); |
| 2415 | i_data[EXT4_IND_BLOCK] = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2416 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2417 | case EXT4_IND_BLOCK: |
| 2418 | nr = i_data[EXT4_DIND_BLOCK]; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2419 | if (nr) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2420 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); |
| 2421 | i_data[EXT4_DIND_BLOCK] = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2422 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2423 | case EXT4_DIND_BLOCK: |
| 2424 | nr = i_data[EXT4_TIND_BLOCK]; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2425 | if (nr) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2426 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); |
| 2427 | i_data[EXT4_TIND_BLOCK] = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2428 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2429 | case EXT4_TIND_BLOCK: |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2430 | ; |
| 2431 | } |
| 2432 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2433 | ext4_discard_reservation(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2434 | |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2435 | up_write(&ei->i_data_sem); |
Kalpak Shah | ef7f383 | 2007-07-18 09:15:20 -0400 | [diff] [blame] | 2436 | inode->i_mtime = inode->i_ctime = ext4_current_time(inode); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2437 | ext4_mark_inode_dirty(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2438 | |
| 2439 | /* |
| 2440 | * In a multi-transaction truncate, we only make the final transaction |
| 2441 | * synchronous |
| 2442 | */ |
| 2443 | if (IS_SYNC(inode)) |
| 2444 | handle->h_sync = 1; |
| 2445 | out_stop: |
| 2446 | /* |
| 2447 | * If this was a simple ftruncate(), and the file will remain alive |
| 2448 | * then we need to clear up the orphan record which we created above. |
| 2449 | * However, if this was a real unlink then we were called by |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2450 | * ext4_delete_inode(), and we allow that function to clean up the |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2451 | * orphan info for us. |
| 2452 | */ |
| 2453 | if (inode->i_nlink) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2454 | ext4_orphan_del(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2455 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2456 | ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2457 | } |
| 2458 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2459 | static ext4_fsblk_t ext4_get_inode_block(struct super_block *sb, |
| 2460 | unsigned long ino, struct ext4_iloc *iloc) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2461 | { |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2462 | unsigned long desc, group_desc; |
| 2463 | ext4_group_t block_group; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2464 | unsigned long offset; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2465 | ext4_fsblk_t block; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2466 | struct buffer_head *bh; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2467 | struct ext4_group_desc * gdp; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2468 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2469 | if (!ext4_valid_inum(sb, ino)) { |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2470 | /* |
| 2471 | * This error is already checked for in namei.c unless we are |
| 2472 | * looking at an NFS filehandle, in which case no error |
| 2473 | * report is needed |
| 2474 | */ |
| 2475 | return 0; |
| 2476 | } |
| 2477 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2478 | block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb); |
| 2479 | if (block_group >= EXT4_SB(sb)->s_groups_count) { |
| 2480 | ext4_error(sb,"ext4_get_inode_block","group >= groups count"); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2481 | return 0; |
| 2482 | } |
| 2483 | smp_rmb(); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2484 | group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb); |
| 2485 | desc = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1); |
| 2486 | bh = EXT4_SB(sb)->s_group_desc[group_desc]; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2487 | if (!bh) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2488 | ext4_error (sb, "ext4_get_inode_block", |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2489 | "Descriptor not loaded"); |
| 2490 | return 0; |
| 2491 | } |
| 2492 | |
Alexandre Ratchov | 0d1ee42 | 2006-10-11 01:21:14 -0700 | [diff] [blame] | 2493 | gdp = (struct ext4_group_desc *)((__u8 *)bh->b_data + |
| 2494 | desc * EXT4_DESC_SIZE(sb)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2495 | /* |
| 2496 | * Figure out the offset within the block group inode table |
| 2497 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2498 | offset = ((ino - 1) % EXT4_INODES_PER_GROUP(sb)) * |
| 2499 | EXT4_INODE_SIZE(sb); |
Alexandre Ratchov | 8fadc14 | 2006-10-11 01:21:15 -0700 | [diff] [blame] | 2500 | block = ext4_inode_table(sb, gdp) + |
| 2501 | (offset >> EXT4_BLOCK_SIZE_BITS(sb)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2502 | |
| 2503 | iloc->block_group = block_group; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2504 | iloc->offset = offset & (EXT4_BLOCK_SIZE(sb) - 1); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2505 | return block; |
| 2506 | } |
| 2507 | |
| 2508 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2509 | * ext4_get_inode_loc returns with an extra refcount against the inode's |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2510 | * underlying buffer_head on success. If 'in_mem' is true, we have all |
| 2511 | * data in memory that is needed to recreate the on-disk version of this |
| 2512 | * inode. |
| 2513 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2514 | static int __ext4_get_inode_loc(struct inode *inode, |
| 2515 | struct ext4_iloc *iloc, int in_mem) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2516 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2517 | ext4_fsblk_t block; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2518 | struct buffer_head *bh; |
| 2519 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2520 | block = ext4_get_inode_block(inode->i_sb, inode->i_ino, iloc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2521 | if (!block) |
| 2522 | return -EIO; |
| 2523 | |
| 2524 | bh = sb_getblk(inode->i_sb, block); |
| 2525 | if (!bh) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2526 | ext4_error (inode->i_sb, "ext4_get_inode_loc", |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2527 | "unable to read inode block - " |
Mingming Cao | 2ae0210 | 2006-10-11 01:21:11 -0700 | [diff] [blame] | 2528 | "inode=%lu, block=%llu", |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2529 | inode->i_ino, block); |
| 2530 | return -EIO; |
| 2531 | } |
| 2532 | if (!buffer_uptodate(bh)) { |
| 2533 | lock_buffer(bh); |
| 2534 | if (buffer_uptodate(bh)) { |
| 2535 | /* someone brought it uptodate while we waited */ |
| 2536 | unlock_buffer(bh); |
| 2537 | goto has_buffer; |
| 2538 | } |
| 2539 | |
| 2540 | /* |
| 2541 | * If we have all information of the inode in memory and this |
| 2542 | * is the only valid inode in the block, we need not read the |
| 2543 | * block. |
| 2544 | */ |
| 2545 | if (in_mem) { |
| 2546 | struct buffer_head *bitmap_bh; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2547 | struct ext4_group_desc *desc; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2548 | int inodes_per_buffer; |
| 2549 | int inode_offset, i; |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2550 | ext4_group_t block_group; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2551 | int start; |
| 2552 | |
| 2553 | block_group = (inode->i_ino - 1) / |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2554 | EXT4_INODES_PER_GROUP(inode->i_sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2555 | inodes_per_buffer = bh->b_size / |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2556 | EXT4_INODE_SIZE(inode->i_sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2557 | inode_offset = ((inode->i_ino - 1) % |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2558 | EXT4_INODES_PER_GROUP(inode->i_sb)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2559 | start = inode_offset & ~(inodes_per_buffer - 1); |
| 2560 | |
| 2561 | /* Is the inode bitmap in cache? */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2562 | desc = ext4_get_group_desc(inode->i_sb, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2563 | block_group, NULL); |
| 2564 | if (!desc) |
| 2565 | goto make_io; |
| 2566 | |
| 2567 | bitmap_bh = sb_getblk(inode->i_sb, |
Alexandre Ratchov | 8fadc14 | 2006-10-11 01:21:15 -0700 | [diff] [blame] | 2568 | ext4_inode_bitmap(inode->i_sb, desc)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2569 | if (!bitmap_bh) |
| 2570 | goto make_io; |
| 2571 | |
| 2572 | /* |
| 2573 | * If the inode bitmap isn't in cache then the |
| 2574 | * optimisation may end up performing two reads instead |
| 2575 | * of one, so skip it. |
| 2576 | */ |
| 2577 | if (!buffer_uptodate(bitmap_bh)) { |
| 2578 | brelse(bitmap_bh); |
| 2579 | goto make_io; |
| 2580 | } |
| 2581 | for (i = start; i < start + inodes_per_buffer; i++) { |
| 2582 | if (i == inode_offset) |
| 2583 | continue; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2584 | if (ext4_test_bit(i, bitmap_bh->b_data)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2585 | break; |
| 2586 | } |
| 2587 | brelse(bitmap_bh); |
| 2588 | if (i == start + inodes_per_buffer) { |
| 2589 | /* all other inodes are free, so skip I/O */ |
| 2590 | memset(bh->b_data, 0, bh->b_size); |
| 2591 | set_buffer_uptodate(bh); |
| 2592 | unlock_buffer(bh); |
| 2593 | goto has_buffer; |
| 2594 | } |
| 2595 | } |
| 2596 | |
| 2597 | make_io: |
| 2598 | /* |
| 2599 | * There are other valid inodes in the buffer, this inode |
| 2600 | * has in-inode xattrs, or we don't have this inode in memory. |
| 2601 | * Read the block from disk. |
| 2602 | */ |
| 2603 | get_bh(bh); |
| 2604 | bh->b_end_io = end_buffer_read_sync; |
| 2605 | submit_bh(READ_META, bh); |
| 2606 | wait_on_buffer(bh); |
| 2607 | if (!buffer_uptodate(bh)) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2608 | ext4_error(inode->i_sb, "ext4_get_inode_loc", |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2609 | "unable to read inode block - " |
Mingming Cao | 2ae0210 | 2006-10-11 01:21:11 -0700 | [diff] [blame] | 2610 | "inode=%lu, block=%llu", |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2611 | inode->i_ino, block); |
| 2612 | brelse(bh); |
| 2613 | return -EIO; |
| 2614 | } |
| 2615 | } |
| 2616 | has_buffer: |
| 2617 | iloc->bh = bh; |
| 2618 | return 0; |
| 2619 | } |
| 2620 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2621 | int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2622 | { |
| 2623 | /* We have all inode data except xattrs in memory here. */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2624 | return __ext4_get_inode_loc(inode, iloc, |
| 2625 | !(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2626 | } |
| 2627 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2628 | void ext4_set_inode_flags(struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2629 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2630 | unsigned int flags = EXT4_I(inode)->i_flags; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2631 | |
| 2632 | inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2633 | if (flags & EXT4_SYNC_FL) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2634 | inode->i_flags |= S_SYNC; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2635 | if (flags & EXT4_APPEND_FL) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2636 | inode->i_flags |= S_APPEND; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2637 | if (flags & EXT4_IMMUTABLE_FL) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2638 | inode->i_flags |= S_IMMUTABLE; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2639 | if (flags & EXT4_NOATIME_FL) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2640 | inode->i_flags |= S_NOATIME; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2641 | if (flags & EXT4_DIRSYNC_FL) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2642 | inode->i_flags |= S_DIRSYNC; |
| 2643 | } |
| 2644 | |
Jan Kara | ff9ddf7 | 2007-07-18 09:24:20 -0400 | [diff] [blame] | 2645 | /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */ |
| 2646 | void ext4_get_inode_flags(struct ext4_inode_info *ei) |
| 2647 | { |
| 2648 | unsigned int flags = ei->vfs_inode.i_flags; |
| 2649 | |
| 2650 | ei->i_flags &= ~(EXT4_SYNC_FL|EXT4_APPEND_FL| |
| 2651 | EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|EXT4_DIRSYNC_FL); |
| 2652 | if (flags & S_SYNC) |
| 2653 | ei->i_flags |= EXT4_SYNC_FL; |
| 2654 | if (flags & S_APPEND) |
| 2655 | ei->i_flags |= EXT4_APPEND_FL; |
| 2656 | if (flags & S_IMMUTABLE) |
| 2657 | ei->i_flags |= EXT4_IMMUTABLE_FL; |
| 2658 | if (flags & S_NOATIME) |
| 2659 | ei->i_flags |= EXT4_NOATIME_FL; |
| 2660 | if (flags & S_DIRSYNC) |
| 2661 | ei->i_flags |= EXT4_DIRSYNC_FL; |
| 2662 | } |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2663 | static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode, |
| 2664 | struct ext4_inode_info *ei) |
| 2665 | { |
| 2666 | blkcnt_t i_blocks ; |
Aneesh Kumar K.V | 8180a56 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2667 | struct inode *inode = &(ei->vfs_inode); |
| 2668 | struct super_block *sb = inode->i_sb; |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2669 | |
| 2670 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, |
| 2671 | EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) { |
| 2672 | /* we are using combined 48 bit field */ |
| 2673 | i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 | |
| 2674 | le32_to_cpu(raw_inode->i_blocks_lo); |
Aneesh Kumar K.V | 8180a56 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2675 | if (ei->i_flags & EXT4_HUGE_FILE_FL) { |
| 2676 | /* i_blocks represent file system block size */ |
| 2677 | return i_blocks << (inode->i_blkbits - 9); |
| 2678 | } else { |
| 2679 | return i_blocks; |
| 2680 | } |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2681 | } else { |
| 2682 | return le32_to_cpu(raw_inode->i_blocks_lo); |
| 2683 | } |
| 2684 | } |
Jan Kara | ff9ddf7 | 2007-07-18 09:24:20 -0400 | [diff] [blame] | 2685 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2686 | void ext4_read_inode(struct inode * inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2687 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2688 | struct ext4_iloc iloc; |
| 2689 | struct ext4_inode *raw_inode; |
| 2690 | struct ext4_inode_info *ei = EXT4_I(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2691 | struct buffer_head *bh; |
| 2692 | int block; |
| 2693 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2694 | #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL |
| 2695 | ei->i_acl = EXT4_ACL_NOT_CACHED; |
| 2696 | ei->i_default_acl = EXT4_ACL_NOT_CACHED; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2697 | #endif |
| 2698 | ei->i_block_alloc_info = NULL; |
| 2699 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2700 | if (__ext4_get_inode_loc(inode, &iloc, 0)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2701 | goto bad_inode; |
| 2702 | bh = iloc.bh; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2703 | raw_inode = ext4_raw_inode(&iloc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2704 | inode->i_mode = le16_to_cpu(raw_inode->i_mode); |
| 2705 | inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); |
| 2706 | inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); |
| 2707 | if(!(test_opt (inode->i_sb, NO_UID32))) { |
| 2708 | inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; |
| 2709 | inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; |
| 2710 | } |
| 2711 | inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2712 | |
| 2713 | ei->i_state = 0; |
| 2714 | ei->i_dir_start_lookup = 0; |
| 2715 | ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); |
| 2716 | /* We now have enough fields to check if the inode was active or not. |
| 2717 | * This is needed because nfsd might try to access dead inodes |
| 2718 | * the test is that same one that e2fsck uses |
| 2719 | * NeilBrown 1999oct15 |
| 2720 | */ |
| 2721 | if (inode->i_nlink == 0) { |
| 2722 | if (inode->i_mode == 0 || |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2723 | !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) { |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2724 | /* this inode is deleted */ |
| 2725 | brelse (bh); |
| 2726 | goto bad_inode; |
| 2727 | } |
| 2728 | /* The only unlinked inodes we let through here have |
| 2729 | * valid i_mode and are being read by the orphan |
| 2730 | * recovery code: that's fine, we're about to complete |
| 2731 | * the process of deleting those. */ |
| 2732 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2733 | ei->i_flags = le32_to_cpu(raw_inode->i_flags); |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2734 | inode->i_blocks = ext4_inode_blocks(raw_inode, ei); |
Aneesh Kumar K.V | 7973c0c | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2735 | ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo); |
Mingming Cao | 9b8f1f0 | 2006-10-11 01:21:13 -0700 | [diff] [blame] | 2736 | if (EXT4_SB(inode->i_sb)->s_es->s_creator_os != |
Aneesh Kumar K.V | a48380f | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2737 | cpu_to_le32(EXT4_OS_HURD)) { |
Badari Pulavarty | a1ddeb7 | 2006-10-11 01:21:09 -0700 | [diff] [blame] | 2738 | ei->i_file_acl |= |
| 2739 | ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2740 | } |
Aneesh Kumar K.V | a48380f | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2741 | inode->i_size = ext4_isize(raw_inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2742 | ei->i_disksize = inode->i_size; |
| 2743 | inode->i_generation = le32_to_cpu(raw_inode->i_generation); |
| 2744 | ei->i_block_group = iloc.block_group; |
| 2745 | /* |
| 2746 | * NOTE! The in-memory inode i_data array is in little-endian order |
| 2747 | * even on big-endian machines: we do NOT byteswap the block numbers! |
| 2748 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2749 | for (block = 0; block < EXT4_N_BLOCKS; block++) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2750 | ei->i_data[block] = raw_inode->i_block[block]; |
| 2751 | INIT_LIST_HEAD(&ei->i_orphan); |
| 2752 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2753 | if (inode->i_ino >= EXT4_FIRST_INO(inode->i_sb) + 1 && |
| 2754 | EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2755 | /* |
| 2756 | * When mke2fs creates big inodes it does not zero out |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2757 | * the unused bytes above EXT4_GOOD_OLD_INODE_SIZE, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2758 | * so ignore those first few inodes. |
| 2759 | */ |
| 2760 | ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2761 | if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > |
Kirill Korotaev | e5d2861 | 2007-06-23 17:16:51 -0700 | [diff] [blame] | 2762 | EXT4_INODE_SIZE(inode->i_sb)) { |
| 2763 | brelse (bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2764 | goto bad_inode; |
Kirill Korotaev | e5d2861 | 2007-06-23 17:16:51 -0700 | [diff] [blame] | 2765 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2766 | if (ei->i_extra_isize == 0) { |
| 2767 | /* The extra space is currently unused. Use it. */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2768 | ei->i_extra_isize = sizeof(struct ext4_inode) - |
| 2769 | EXT4_GOOD_OLD_INODE_SIZE; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2770 | } else { |
| 2771 | __le32 *magic = (void *)raw_inode + |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2772 | EXT4_GOOD_OLD_INODE_SIZE + |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2773 | ei->i_extra_isize; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2774 | if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC)) |
| 2775 | ei->i_state |= EXT4_STATE_XATTR; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2776 | } |
| 2777 | } else |
| 2778 | ei->i_extra_isize = 0; |
| 2779 | |
Kalpak Shah | ef7f383 | 2007-07-18 09:15:20 -0400 | [diff] [blame] | 2780 | EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode); |
| 2781 | EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode); |
| 2782 | EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode); |
| 2783 | EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode); |
| 2784 | |
Jean Noel Cordenner | 25ec56b | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2785 | inode->i_version = le32_to_cpu(raw_inode->i_disk_version); |
| 2786 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { |
| 2787 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) |
| 2788 | inode->i_version |= |
| 2789 | (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32; |
| 2790 | } |
| 2791 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2792 | if (S_ISREG(inode->i_mode)) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2793 | inode->i_op = &ext4_file_inode_operations; |
| 2794 | inode->i_fop = &ext4_file_operations; |
| 2795 | ext4_set_aops(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2796 | } else if (S_ISDIR(inode->i_mode)) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2797 | inode->i_op = &ext4_dir_inode_operations; |
| 2798 | inode->i_fop = &ext4_dir_operations; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2799 | } else if (S_ISLNK(inode->i_mode)) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2800 | if (ext4_inode_is_fast_symlink(inode)) |
| 2801 | inode->i_op = &ext4_fast_symlink_inode_operations; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2802 | else { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2803 | inode->i_op = &ext4_symlink_inode_operations; |
| 2804 | ext4_set_aops(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2805 | } |
| 2806 | } else { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2807 | inode->i_op = &ext4_special_inode_operations; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2808 | if (raw_inode->i_block[0]) |
| 2809 | init_special_inode(inode, inode->i_mode, |
| 2810 | old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); |
| 2811 | else |
| 2812 | init_special_inode(inode, inode->i_mode, |
| 2813 | new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); |
| 2814 | } |
| 2815 | brelse (iloc.bh); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2816 | ext4_set_inode_flags(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2817 | return; |
| 2818 | |
| 2819 | bad_inode: |
| 2820 | make_bad_inode(inode); |
| 2821 | return; |
| 2822 | } |
| 2823 | |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2824 | static int ext4_inode_blocks_set(handle_t *handle, |
| 2825 | struct ext4_inode *raw_inode, |
| 2826 | struct ext4_inode_info *ei) |
| 2827 | { |
| 2828 | struct inode *inode = &(ei->vfs_inode); |
| 2829 | u64 i_blocks = inode->i_blocks; |
| 2830 | struct super_block *sb = inode->i_sb; |
| 2831 | int err = 0; |
| 2832 | |
| 2833 | if (i_blocks <= ~0U) { |
| 2834 | /* |
| 2835 | * i_blocks can be represnted in a 32 bit variable |
| 2836 | * as multiple of 512 bytes |
| 2837 | */ |
Aneesh Kumar K.V | 8180a56 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2838 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2839 | raw_inode->i_blocks_high = 0; |
Aneesh Kumar K.V | 8180a56 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2840 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2841 | } else if (i_blocks <= 0xffffffffffffULL) { |
| 2842 | /* |
| 2843 | * i_blocks can be represented in a 48 bit variable |
| 2844 | * as multiple of 512 bytes |
| 2845 | */ |
| 2846 | err = ext4_update_rocompat_feature(handle, sb, |
| 2847 | EXT4_FEATURE_RO_COMPAT_HUGE_FILE); |
| 2848 | if (err) |
| 2849 | goto err_out; |
| 2850 | /* i_block is stored in the split 48 bit fields */ |
Aneesh Kumar K.V | 8180a56 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2851 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2852 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); |
Aneesh Kumar K.V | 8180a56 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2853 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2854 | } else { |
Aneesh Kumar K.V | 8180a56 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2855 | /* |
| 2856 | * i_blocks should be represented in a 48 bit variable |
| 2857 | * as multiple of file system block size |
| 2858 | */ |
| 2859 | err = ext4_update_rocompat_feature(handle, sb, |
| 2860 | EXT4_FEATURE_RO_COMPAT_HUGE_FILE); |
| 2861 | if (err) |
| 2862 | goto err_out; |
| 2863 | ei->i_flags |= EXT4_HUGE_FILE_FL; |
| 2864 | /* i_block is stored in file system block size */ |
| 2865 | i_blocks = i_blocks >> (inode->i_blkbits - 9); |
| 2866 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
| 2867 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2868 | } |
| 2869 | err_out: |
| 2870 | return err; |
| 2871 | } |
| 2872 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2873 | /* |
| 2874 | * Post the struct inode info into an on-disk inode location in the |
| 2875 | * buffer-cache. This gobbles the caller's reference to the |
| 2876 | * buffer_head in the inode location struct. |
| 2877 | * |
| 2878 | * The caller must have write access to iloc->bh. |
| 2879 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2880 | static int ext4_do_update_inode(handle_t *handle, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2881 | struct inode *inode, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2882 | struct ext4_iloc *iloc) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2883 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2884 | struct ext4_inode *raw_inode = ext4_raw_inode(iloc); |
| 2885 | struct ext4_inode_info *ei = EXT4_I(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2886 | struct buffer_head *bh = iloc->bh; |
| 2887 | int err = 0, rc, block; |
| 2888 | |
| 2889 | /* For fields not not tracking in the in-memory inode, |
| 2890 | * initialise them to zero for new inodes. */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2891 | if (ei->i_state & EXT4_STATE_NEW) |
| 2892 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2893 | |
Jan Kara | ff9ddf7 | 2007-07-18 09:24:20 -0400 | [diff] [blame] | 2894 | ext4_get_inode_flags(ei); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2895 | raw_inode->i_mode = cpu_to_le16(inode->i_mode); |
| 2896 | if(!(test_opt(inode->i_sb, NO_UID32))) { |
| 2897 | raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid)); |
| 2898 | raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid)); |
| 2899 | /* |
| 2900 | * Fix up interoperability with old kernels. Otherwise, old inodes get |
| 2901 | * re-used with the upper 16 bits of the uid/gid intact |
| 2902 | */ |
| 2903 | if(!ei->i_dtime) { |
| 2904 | raw_inode->i_uid_high = |
| 2905 | cpu_to_le16(high_16_bits(inode->i_uid)); |
| 2906 | raw_inode->i_gid_high = |
| 2907 | cpu_to_le16(high_16_bits(inode->i_gid)); |
| 2908 | } else { |
| 2909 | raw_inode->i_uid_high = 0; |
| 2910 | raw_inode->i_gid_high = 0; |
| 2911 | } |
| 2912 | } else { |
| 2913 | raw_inode->i_uid_low = |
| 2914 | cpu_to_le16(fs_high2lowuid(inode->i_uid)); |
| 2915 | raw_inode->i_gid_low = |
| 2916 | cpu_to_le16(fs_high2lowgid(inode->i_gid)); |
| 2917 | raw_inode->i_uid_high = 0; |
| 2918 | raw_inode->i_gid_high = 0; |
| 2919 | } |
| 2920 | raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); |
Kalpak Shah | ef7f383 | 2007-07-18 09:15:20 -0400 | [diff] [blame] | 2921 | |
| 2922 | EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode); |
| 2923 | EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode); |
| 2924 | EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode); |
| 2925 | EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode); |
| 2926 | |
Aneesh Kumar K.V | 0fc1b45 | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 2927 | if (ext4_inode_blocks_set(handle, raw_inode, ei)) |
| 2928 | goto out_brelse; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2929 | raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); |
| 2930 | raw_inode->i_flags = cpu_to_le32(ei->i_flags); |
Mingming Cao | 9b8f1f0 | 2006-10-11 01:21:13 -0700 | [diff] [blame] | 2931 | if (EXT4_SB(inode->i_sb)->s_es->s_creator_os != |
| 2932 | cpu_to_le32(EXT4_OS_HURD)) |
Badari Pulavarty | a1ddeb7 | 2006-10-11 01:21:09 -0700 | [diff] [blame] | 2933 | raw_inode->i_file_acl_high = |
| 2934 | cpu_to_le16(ei->i_file_acl >> 32); |
Aneesh Kumar K.V | 7973c0c | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2935 | raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl); |
Aneesh Kumar K.V | a48380f | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2936 | ext4_isize_set(raw_inode, ei->i_disksize); |
| 2937 | if (ei->i_disksize > 0x7fffffffULL) { |
| 2938 | struct super_block *sb = inode->i_sb; |
| 2939 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, |
| 2940 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE) || |
| 2941 | EXT4_SB(sb)->s_es->s_rev_level == |
| 2942 | cpu_to_le32(EXT4_GOOD_OLD_REV)) { |
| 2943 | /* If this is the first large file |
| 2944 | * created, add a flag to the superblock. |
| 2945 | */ |
| 2946 | err = ext4_journal_get_write_access(handle, |
| 2947 | EXT4_SB(sb)->s_sbh); |
| 2948 | if (err) |
| 2949 | goto out_brelse; |
| 2950 | ext4_update_dynamic_rev(sb); |
| 2951 | EXT4_SET_RO_COMPAT_FEATURE(sb, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2952 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE); |
Aneesh Kumar K.V | a48380f | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2953 | sb->s_dirt = 1; |
| 2954 | handle->h_sync = 1; |
| 2955 | err = ext4_journal_dirty_metadata(handle, |
| 2956 | EXT4_SB(sb)->s_sbh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2957 | } |
| 2958 | } |
| 2959 | raw_inode->i_generation = cpu_to_le32(inode->i_generation); |
| 2960 | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { |
| 2961 | if (old_valid_dev(inode->i_rdev)) { |
| 2962 | raw_inode->i_block[0] = |
| 2963 | cpu_to_le32(old_encode_dev(inode->i_rdev)); |
| 2964 | raw_inode->i_block[1] = 0; |
| 2965 | } else { |
| 2966 | raw_inode->i_block[0] = 0; |
| 2967 | raw_inode->i_block[1] = |
| 2968 | cpu_to_le32(new_encode_dev(inode->i_rdev)); |
| 2969 | raw_inode->i_block[2] = 0; |
| 2970 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2971 | } else for (block = 0; block < EXT4_N_BLOCKS; block++) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2972 | raw_inode->i_block[block] = ei->i_data[block]; |
| 2973 | |
Jean Noel Cordenner | 25ec56b | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2974 | raw_inode->i_disk_version = cpu_to_le32(inode->i_version); |
| 2975 | if (ei->i_extra_isize) { |
| 2976 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) |
| 2977 | raw_inode->i_version_hi = |
| 2978 | cpu_to_le32(inode->i_version >> 32); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2979 | raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); |
Jean Noel Cordenner | 25ec56b | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2980 | } |
| 2981 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2982 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2983 | BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata"); |
| 2984 | rc = ext4_journal_dirty_metadata(handle, bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2985 | if (!err) |
| 2986 | err = rc; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2987 | ei->i_state &= ~EXT4_STATE_NEW; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2988 | |
| 2989 | out_brelse: |
| 2990 | brelse (bh); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2991 | ext4_std_error(inode->i_sb, err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2992 | return err; |
| 2993 | } |
| 2994 | |
| 2995 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2996 | * ext4_write_inode() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 2997 | * |
| 2998 | * We are called from a few places: |
| 2999 | * |
| 3000 | * - Within generic_file_write() for O_SYNC files. |
| 3001 | * Here, there will be no transaction running. We wait for any running |
| 3002 | * trasnaction to commit. |
| 3003 | * |
| 3004 | * - Within sys_sync(), kupdate and such. |
| 3005 | * We wait on commit, if tol to. |
| 3006 | * |
| 3007 | * - Within prune_icache() (PF_MEMALLOC == true) |
| 3008 | * Here we simply return. We can't afford to block kswapd on the |
| 3009 | * journal commit. |
| 3010 | * |
| 3011 | * In all cases it is actually safe for us to return without doing anything, |
| 3012 | * because the inode has been copied into a raw inode buffer in |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3013 | * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3014 | * knfsd. |
| 3015 | * |
| 3016 | * Note that we are absolutely dependent upon all inode dirtiers doing the |
| 3017 | * right thing: they *must* call mark_inode_dirty() after dirtying info in |
| 3018 | * which we are interested. |
| 3019 | * |
| 3020 | * It would be a bug for them to not do this. The code: |
| 3021 | * |
| 3022 | * mark_inode_dirty(inode) |
| 3023 | * stuff(); |
| 3024 | * inode->i_size = expr; |
| 3025 | * |
| 3026 | * is in error because a kswapd-driven write_inode() could occur while |
| 3027 | * `stuff()' is running, and the new i_size will be lost. Plus the inode |
| 3028 | * will no longer be on the superblock's dirty inode list. |
| 3029 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3030 | int ext4_write_inode(struct inode *inode, int wait) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3031 | { |
| 3032 | if (current->flags & PF_MEMALLOC) |
| 3033 | return 0; |
| 3034 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3035 | if (ext4_journal_current_handle()) { |
Mingming Cao | b38bd33 | 2007-07-19 01:48:35 -0700 | [diff] [blame] | 3036 | jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n"); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3037 | dump_stack(); |
| 3038 | return -EIO; |
| 3039 | } |
| 3040 | |
| 3041 | if (!wait) |
| 3042 | return 0; |
| 3043 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3044 | return ext4_force_commit(inode->i_sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3045 | } |
| 3046 | |
| 3047 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3048 | * ext4_setattr() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3049 | * |
| 3050 | * Called from notify_change. |
| 3051 | * |
| 3052 | * We want to trap VFS attempts to truncate the file as soon as |
| 3053 | * possible. In particular, we want to make sure that when the VFS |
| 3054 | * shrinks i_size, we put the inode on the orphan list and modify |
| 3055 | * i_disksize immediately, so that during the subsequent flushing of |
| 3056 | * dirty pages and freeing of disk blocks, we can guarantee that any |
| 3057 | * commit will leave the blocks being flushed in an unused state on |
| 3058 | * disk. (On recovery, the inode will get truncated and the blocks will |
| 3059 | * be freed, so we have a strong guarantee that no future commit will |
| 3060 | * leave these blocks visible to the user.) |
| 3061 | * |
| 3062 | * Called with inode->sem down. |
| 3063 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3064 | int ext4_setattr(struct dentry *dentry, struct iattr *attr) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3065 | { |
| 3066 | struct inode *inode = dentry->d_inode; |
| 3067 | int error, rc = 0; |
| 3068 | const unsigned int ia_valid = attr->ia_valid; |
| 3069 | |
| 3070 | error = inode_change_ok(inode, attr); |
| 3071 | if (error) |
| 3072 | return error; |
| 3073 | |
| 3074 | if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || |
| 3075 | (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) { |
| 3076 | handle_t *handle; |
| 3077 | |
| 3078 | /* (user+group)*(old+new) structure, inode write (sb, |
| 3079 | * inode block, ? - but truncate inode update has it) */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3080 | handle = ext4_journal_start(inode, 2*(EXT4_QUOTA_INIT_BLOCKS(inode->i_sb)+ |
| 3081 | EXT4_QUOTA_DEL_BLOCKS(inode->i_sb))+3); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3082 | if (IS_ERR(handle)) { |
| 3083 | error = PTR_ERR(handle); |
| 3084 | goto err_out; |
| 3085 | } |
| 3086 | error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0; |
| 3087 | if (error) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3088 | ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3089 | return error; |
| 3090 | } |
| 3091 | /* Update corresponding info in inode so that everything is in |
| 3092 | * one transaction */ |
| 3093 | if (attr->ia_valid & ATTR_UID) |
| 3094 | inode->i_uid = attr->ia_uid; |
| 3095 | if (attr->ia_valid & ATTR_GID) |
| 3096 | inode->i_gid = attr->ia_gid; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3097 | error = ext4_mark_inode_dirty(handle, inode); |
| 3098 | ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3099 | } |
| 3100 | |
Eric Sandeen | e2b4657 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 3101 | if (attr->ia_valid & ATTR_SIZE) { |
| 3102 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) { |
| 3103 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 3104 | |
| 3105 | if (attr->ia_size > sbi->s_bitmap_maxbytes) { |
| 3106 | error = -EFBIG; |
| 3107 | goto err_out; |
| 3108 | } |
| 3109 | } |
| 3110 | } |
| 3111 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3112 | if (S_ISREG(inode->i_mode) && |
| 3113 | attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { |
| 3114 | handle_t *handle; |
| 3115 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3116 | handle = ext4_journal_start(inode, 3); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3117 | if (IS_ERR(handle)) { |
| 3118 | error = PTR_ERR(handle); |
| 3119 | goto err_out; |
| 3120 | } |
| 3121 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3122 | error = ext4_orphan_add(handle, inode); |
| 3123 | EXT4_I(inode)->i_disksize = attr->ia_size; |
| 3124 | rc = ext4_mark_inode_dirty(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3125 | if (!error) |
| 3126 | error = rc; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3127 | ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3128 | } |
| 3129 | |
| 3130 | rc = inode_setattr(inode, attr); |
| 3131 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3132 | /* If inode_setattr's call to ext4_truncate failed to get a |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3133 | * transaction handle at all, we need to clean up the in-core |
| 3134 | * orphan list manually. */ |
| 3135 | if (inode->i_nlink) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3136 | ext4_orphan_del(NULL, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3137 | |
| 3138 | if (!rc && (ia_valid & ATTR_MODE)) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3139 | rc = ext4_acl_chmod(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3140 | |
| 3141 | err_out: |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3142 | ext4_std_error(inode->i_sb, error); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3143 | if (!error) |
| 3144 | error = rc; |
| 3145 | return error; |
| 3146 | } |
| 3147 | |
| 3148 | |
| 3149 | /* |
| 3150 | * How many blocks doth make a writepage()? |
| 3151 | * |
| 3152 | * With N blocks per page, it may be: |
| 3153 | * N data blocks |
| 3154 | * 2 indirect block |
| 3155 | * 2 dindirect |
| 3156 | * 1 tindirect |
| 3157 | * N+5 bitmap blocks (from the above) |
| 3158 | * N+5 group descriptor summary blocks |
| 3159 | * 1 inode block |
| 3160 | * 1 superblock. |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3161 | * 2 * EXT4_SINGLEDATA_TRANS_BLOCKS for the quote files |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3162 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3163 | * 3 * (N + 5) + 2 + 2 * EXT4_SINGLEDATA_TRANS_BLOCKS |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3164 | * |
| 3165 | * With ordered or writeback data it's the same, less the N data blocks. |
| 3166 | * |
| 3167 | * If the inode's direct blocks can hold an integral number of pages then a |
| 3168 | * page cannot straddle two indirect blocks, and we can only touch one indirect |
| 3169 | * and dindirect block, and the "5" above becomes "3". |
| 3170 | * |
| 3171 | * This still overestimates under most circumstances. If we were to pass the |
| 3172 | * start and end offsets in here as well we could do block_to_path() on each |
| 3173 | * block and work out the exact number of indirects which are touched. Pah. |
| 3174 | */ |
| 3175 | |
Alex Tomas | a86c618 | 2006-10-11 01:21:03 -0700 | [diff] [blame] | 3176 | int ext4_writepage_trans_blocks(struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3177 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3178 | int bpp = ext4_journal_blocks_per_page(inode); |
| 3179 | int indirects = (EXT4_NDIR_BLOCKS % bpp) ? 5 : 3; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3180 | int ret; |
| 3181 | |
Alex Tomas | a86c618 | 2006-10-11 01:21:03 -0700 | [diff] [blame] | 3182 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) |
| 3183 | return ext4_ext_writepage_trans_blocks(inode, bpp); |
| 3184 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3185 | if (ext4_should_journal_data(inode)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3186 | ret = 3 * (bpp + indirects) + 2; |
| 3187 | else |
| 3188 | ret = 2 * (bpp + indirects) + 2; |
| 3189 | |
| 3190 | #ifdef CONFIG_QUOTA |
| 3191 | /* We know that structure was already allocated during DQUOT_INIT so |
| 3192 | * we will be updating only the data blocks + inodes */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3193 | ret += 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3194 | #endif |
| 3195 | |
| 3196 | return ret; |
| 3197 | } |
| 3198 | |
| 3199 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3200 | * The caller must have previously called ext4_reserve_inode_write(). |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3201 | * Give this, we know that the caller already has write access to iloc->bh. |
| 3202 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3203 | int ext4_mark_iloc_dirty(handle_t *handle, |
| 3204 | struct inode *inode, struct ext4_iloc *iloc) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3205 | { |
| 3206 | int err = 0; |
| 3207 | |
Jean Noel Cordenner | 25ec56b | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 3208 | if (test_opt(inode->i_sb, I_VERSION)) |
| 3209 | inode_inc_iversion(inode); |
| 3210 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3211 | /* the do_update_inode consumes one bh->b_count */ |
| 3212 | get_bh(iloc->bh); |
| 3213 | |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 3214 | /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3215 | err = ext4_do_update_inode(handle, inode, iloc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3216 | put_bh(iloc->bh); |
| 3217 | return err; |
| 3218 | } |
| 3219 | |
| 3220 | /* |
| 3221 | * On success, We end up with an outstanding reference count against |
| 3222 | * iloc->bh. This _must_ be cleaned up later. |
| 3223 | */ |
| 3224 | |
| 3225 | int |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3226 | ext4_reserve_inode_write(handle_t *handle, struct inode *inode, |
| 3227 | struct ext4_iloc *iloc) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3228 | { |
| 3229 | int err = 0; |
| 3230 | if (handle) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3231 | err = ext4_get_inode_loc(inode, iloc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3232 | if (!err) { |
| 3233 | BUFFER_TRACE(iloc->bh, "get_write_access"); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3234 | err = ext4_journal_get_write_access(handle, iloc->bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3235 | if (err) { |
| 3236 | brelse(iloc->bh); |
| 3237 | iloc->bh = NULL; |
| 3238 | } |
| 3239 | } |
| 3240 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3241 | ext4_std_error(inode->i_sb, err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3242 | return err; |
| 3243 | } |
| 3244 | |
| 3245 | /* |
Kalpak Shah | 6dd4ee7 | 2007-07-18 09:19:57 -0400 | [diff] [blame] | 3246 | * Expand an inode by new_extra_isize bytes. |
| 3247 | * Returns 0 on success or negative error number on failure. |
| 3248 | */ |
Aneesh Kumar K.V | 1d03ec9 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 3249 | static int ext4_expand_extra_isize(struct inode *inode, |
| 3250 | unsigned int new_extra_isize, |
| 3251 | struct ext4_iloc iloc, |
| 3252 | handle_t *handle) |
Kalpak Shah | 6dd4ee7 | 2007-07-18 09:19:57 -0400 | [diff] [blame] | 3253 | { |
| 3254 | struct ext4_inode *raw_inode; |
| 3255 | struct ext4_xattr_ibody_header *header; |
| 3256 | struct ext4_xattr_entry *entry; |
| 3257 | |
| 3258 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) |
| 3259 | return 0; |
| 3260 | |
| 3261 | raw_inode = ext4_raw_inode(&iloc); |
| 3262 | |
| 3263 | header = IHDR(inode, raw_inode); |
| 3264 | entry = IFIRST(header); |
| 3265 | |
| 3266 | /* No extended attributes present */ |
| 3267 | if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR) || |
| 3268 | header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { |
| 3269 | memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0, |
| 3270 | new_extra_isize); |
| 3271 | EXT4_I(inode)->i_extra_isize = new_extra_isize; |
| 3272 | return 0; |
| 3273 | } |
| 3274 | |
| 3275 | /* try to expand with EAs present */ |
| 3276 | return ext4_expand_extra_isize_ea(inode, new_extra_isize, |
| 3277 | raw_inode, handle); |
| 3278 | } |
| 3279 | |
| 3280 | /* |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3281 | * What we do here is to mark the in-core inode as clean with respect to inode |
| 3282 | * dirtiness (it may still be data-dirty). |
| 3283 | * This means that the in-core inode may be reaped by prune_icache |
| 3284 | * without having to perform any I/O. This is a very good thing, |
| 3285 | * because *any* task may call prune_icache - even ones which |
| 3286 | * have a transaction open against a different journal. |
| 3287 | * |
| 3288 | * Is this cheating? Not really. Sure, we haven't written the |
| 3289 | * inode out, but prune_icache isn't a user-visible syncing function. |
| 3290 | * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) |
| 3291 | * we start and wait on commits. |
| 3292 | * |
| 3293 | * Is this efficient/effective? Well, we're being nice to the system |
| 3294 | * by cleaning up our inodes proactively so they can be reaped |
| 3295 | * without I/O. But we are potentially leaving up to five seconds' |
| 3296 | * worth of inodes floating about which prune_icache wants us to |
| 3297 | * write out. One way to fix that would be to get prune_icache() |
| 3298 | * to do a write_super() to free up some memory. It has the desired |
| 3299 | * effect. |
| 3300 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3301 | int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3302 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3303 | struct ext4_iloc iloc; |
Kalpak Shah | 6dd4ee7 | 2007-07-18 09:19:57 -0400 | [diff] [blame] | 3304 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 3305 | static unsigned int mnt_count; |
| 3306 | int err, ret; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3307 | |
| 3308 | might_sleep(); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3309 | err = ext4_reserve_inode_write(handle, inode, &iloc); |
Kalpak Shah | 6dd4ee7 | 2007-07-18 09:19:57 -0400 | [diff] [blame] | 3310 | if (EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize && |
| 3311 | !(EXT4_I(inode)->i_state & EXT4_STATE_NO_EXPAND)) { |
| 3312 | /* |
| 3313 | * We need extra buffer credits since we may write into EA block |
| 3314 | * with this same handle. If journal_extend fails, then it will |
| 3315 | * only result in a minor loss of functionality for that inode. |
| 3316 | * If this is felt to be critical, then e2fsck should be run to |
| 3317 | * force a large enough s_min_extra_isize. |
| 3318 | */ |
| 3319 | if ((jbd2_journal_extend(handle, |
| 3320 | EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) { |
| 3321 | ret = ext4_expand_extra_isize(inode, |
| 3322 | sbi->s_want_extra_isize, |
| 3323 | iloc, handle); |
| 3324 | if (ret) { |
| 3325 | EXT4_I(inode)->i_state |= EXT4_STATE_NO_EXPAND; |
Aneesh Kumar K.V | c1bddad | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 3326 | if (mnt_count != |
| 3327 | le16_to_cpu(sbi->s_es->s_mnt_count)) { |
Kalpak Shah | 6dd4ee7 | 2007-07-18 09:19:57 -0400 | [diff] [blame] | 3328 | ext4_warning(inode->i_sb, __FUNCTION__, |
| 3329 | "Unable to expand inode %lu. Delete" |
| 3330 | " some EAs or run e2fsck.", |
| 3331 | inode->i_ino); |
Aneesh Kumar K.V | c1bddad | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 3332 | mnt_count = |
| 3333 | le16_to_cpu(sbi->s_es->s_mnt_count); |
Kalpak Shah | 6dd4ee7 | 2007-07-18 09:19:57 -0400 | [diff] [blame] | 3334 | } |
| 3335 | } |
| 3336 | } |
| 3337 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3338 | if (!err) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3339 | err = ext4_mark_iloc_dirty(handle, inode, &iloc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3340 | return err; |
| 3341 | } |
| 3342 | |
| 3343 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3344 | * ext4_dirty_inode() is called from __mark_inode_dirty() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3345 | * |
| 3346 | * We're really interested in the case where a file is being extended. |
| 3347 | * i_size has been changed by generic_commit_write() and we thus need |
| 3348 | * to include the updated inode in the current transaction. |
| 3349 | * |
| 3350 | * Also, DQUOT_ALLOC_SPACE() will always dirty the inode when blocks |
| 3351 | * are allocated to the file. |
| 3352 | * |
| 3353 | * If the inode is marked synchronous, we don't honour that here - doing |
| 3354 | * so would cause a commit on atime updates, which we don't bother doing. |
| 3355 | * We handle synchronous inodes at the highest possible level. |
| 3356 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3357 | void ext4_dirty_inode(struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3358 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3359 | handle_t *current_handle = ext4_journal_current_handle(); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3360 | handle_t *handle; |
| 3361 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3362 | handle = ext4_journal_start(inode, 2); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3363 | if (IS_ERR(handle)) |
| 3364 | goto out; |
| 3365 | if (current_handle && |
| 3366 | current_handle->h_transaction != handle->h_transaction) { |
| 3367 | /* This task has a transaction open against a different fs */ |
| 3368 | printk(KERN_EMERG "%s: transactions do not match!\n", |
| 3369 | __FUNCTION__); |
| 3370 | } else { |
| 3371 | jbd_debug(5, "marking dirty. outer handle=%p\n", |
| 3372 | current_handle); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3373 | ext4_mark_inode_dirty(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3374 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3375 | ext4_journal_stop(handle); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3376 | out: |
| 3377 | return; |
| 3378 | } |
| 3379 | |
| 3380 | #if 0 |
| 3381 | /* |
| 3382 | * Bind an inode's backing buffer_head into this transaction, to prevent |
| 3383 | * it from being flushed to disk early. Unlike |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3384 | * ext4_reserve_inode_write, this leaves behind no bh reference and |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3385 | * returns no iloc structure, so the caller needs to repeat the iloc |
| 3386 | * lookup to mark the inode dirty later. |
| 3387 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3388 | static int ext4_pin_inode(handle_t *handle, struct inode *inode) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3389 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3390 | struct ext4_iloc iloc; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3391 | |
| 3392 | int err = 0; |
| 3393 | if (handle) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3394 | err = ext4_get_inode_loc(inode, &iloc); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3395 | if (!err) { |
| 3396 | BUFFER_TRACE(iloc.bh, "get_write_access"); |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 3397 | err = jbd2_journal_get_write_access(handle, iloc.bh); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3398 | if (!err) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3399 | err = ext4_journal_dirty_metadata(handle, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3400 | iloc.bh); |
| 3401 | brelse(iloc.bh); |
| 3402 | } |
| 3403 | } |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3404 | ext4_std_error(inode->i_sb, err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3405 | return err; |
| 3406 | } |
| 3407 | #endif |
| 3408 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3409 | int ext4_change_inode_journal_flag(struct inode *inode, int val) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3410 | { |
| 3411 | journal_t *journal; |
| 3412 | handle_t *handle; |
| 3413 | int err; |
| 3414 | |
| 3415 | /* |
| 3416 | * We have to be very careful here: changing a data block's |
| 3417 | * journaling status dynamically is dangerous. If we write a |
| 3418 | * data block to the journal, change the status and then delete |
| 3419 | * that block, we risk forgetting to revoke the old log record |
| 3420 | * from the journal and so a subsequent replay can corrupt data. |
| 3421 | * So, first we make sure that the journal is empty and that |
| 3422 | * nobody is changing anything. |
| 3423 | */ |
| 3424 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3425 | journal = EXT4_JOURNAL(inode); |
Dave Hansen | d699594 | 2007-07-18 08:33:51 -0400 | [diff] [blame] | 3426 | if (is_journal_aborted(journal)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3427 | return -EROFS; |
| 3428 | |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 3429 | jbd2_journal_lock_updates(journal); |
| 3430 | jbd2_journal_flush(journal); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3431 | |
| 3432 | /* |
| 3433 | * OK, there are no updates running now, and all cached data is |
| 3434 | * synced to disk. We are now in a completely consistent state |
| 3435 | * which doesn't have anything in the journal, and we know that |
| 3436 | * no filesystem updates are running, so it is safe to modify |
| 3437 | * the inode's in-core data-journaling state flag now. |
| 3438 | */ |
| 3439 | |
| 3440 | if (val) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3441 | EXT4_I(inode)->i_flags |= EXT4_JOURNAL_DATA_FL; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3442 | else |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3443 | EXT4_I(inode)->i_flags &= ~EXT4_JOURNAL_DATA_FL; |
| 3444 | ext4_set_aops(inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3445 | |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 3446 | jbd2_journal_unlock_updates(journal); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3447 | |
| 3448 | /* Finally we can mark the inode as dirty. */ |
| 3449 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3450 | handle = ext4_journal_start(inode, 1); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3451 | if (IS_ERR(handle)) |
| 3452 | return PTR_ERR(handle); |
| 3453 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3454 | err = ext4_mark_inode_dirty(handle, inode); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3455 | handle->h_sync = 1; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 3456 | ext4_journal_stop(handle); |
| 3457 | ext4_std_error(inode->i_sb, err); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3458 | |
| 3459 | return err; |
| 3460 | } |