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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/ext3/inode.c | |
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 | |
e9ad5620 | 16 | * (sct@redhat.com), 1993, 1998 |
1da177e4 LT |
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 | |
e9ad5620 | 20 | * (jj@sunsite.ms.mff.cuni.cz) |
1da177e4 LT |
21 | * |
22 | * Assorted race fixes, rewrite of ext3_get_block() by Al Viro, 2000 | |
23 | */ | |
24 | ||
25 | #include <linux/module.h> | |
26 | #include <linux/fs.h> | |
27 | #include <linux/time.h> | |
28 | #include <linux/ext3_jbd.h> | |
29 | #include <linux/jbd.h> | |
1da177e4 LT |
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> | |
caa38fb0 | 38 | #include <linux/bio.h> |
68c9d702 | 39 | #include <linux/fiemap.h> |
1da177e4 LT |
40 | #include "xattr.h" |
41 | #include "acl.h" | |
42 | ||
43 | static int ext3_writepage_trans_blocks(struct inode *inode); | |
44 | ||
45 | /* | |
46 | * Test whether an inode is a fast symlink. | |
47 | */ | |
d6859bfc | 48 | static int ext3_inode_is_fast_symlink(struct inode *inode) |
1da177e4 LT |
49 | { |
50 | int ea_blocks = EXT3_I(inode)->i_file_acl ? | |
51 | (inode->i_sb->s_blocksize >> 9) : 0; | |
52 | ||
d6859bfc | 53 | return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); |
1da177e4 LT |
54 | } |
55 | ||
d6859bfc AM |
56 | /* |
57 | * The ext3 forget function must perform a revoke if we are freeing data | |
1da177e4 | 58 | * which has been journaled. Metadata (eg. indirect blocks) must be |
ae6ddcc5 | 59 | * revoked in all cases. |
1da177e4 LT |
60 | * |
61 | * "bh" may be NULL: a metadata block may have been freed from memory | |
62 | * but there may still be a record of it in the journal, and that record | |
63 | * still needs to be revoked. | |
64 | */ | |
d6859bfc | 65 | int ext3_forget(handle_t *handle, int is_metadata, struct inode *inode, |
1c2bf374 | 66 | struct buffer_head *bh, ext3_fsblk_t blocknr) |
1da177e4 LT |
67 | { |
68 | int err; | |
69 | ||
70 | might_sleep(); | |
71 | ||
72 | BUFFER_TRACE(bh, "enter"); | |
73 | ||
74 | jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " | |
75 | "data mode %lx\n", | |
76 | bh, is_metadata, inode->i_mode, | |
77 | test_opt(inode->i_sb, DATA_FLAGS)); | |
78 | ||
79 | /* Never use the revoke function if we are doing full data | |
80 | * journaling: there is no need to, and a V1 superblock won't | |
81 | * support it. Otherwise, only skip the revoke on un-journaled | |
82 | * data blocks. */ | |
83 | ||
84 | if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA || | |
85 | (!is_metadata && !ext3_should_journal_data(inode))) { | |
86 | if (bh) { | |
87 | BUFFER_TRACE(bh, "call journal_forget"); | |
88 | return ext3_journal_forget(handle, bh); | |
89 | } | |
90 | return 0; | |
91 | } | |
92 | ||
93 | /* | |
94 | * data!=journal && (is_metadata || should_journal_data(inode)) | |
95 | */ | |
96 | BUFFER_TRACE(bh, "call ext3_journal_revoke"); | |
97 | err = ext3_journal_revoke(handle, blocknr, bh); | |
98 | if (err) | |
e05b6b52 | 99 | ext3_abort(inode->i_sb, __func__, |
1da177e4 LT |
100 | "error %d when attempting revoke", err); |
101 | BUFFER_TRACE(bh, "exit"); | |
102 | return err; | |
103 | } | |
104 | ||
105 | /* | |
d6859bfc | 106 | * Work out how many blocks we need to proceed with the next chunk of a |
1da177e4 LT |
107 | * truncate transaction. |
108 | */ | |
ae6ddcc5 | 109 | static unsigned long blocks_for_truncate(struct inode *inode) |
1da177e4 LT |
110 | { |
111 | unsigned long needed; | |
112 | ||
113 | needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); | |
114 | ||
115 | /* Give ourselves just enough room to cope with inodes in which | |
116 | * i_blocks is corrupt: we've seen disk corruptions in the past | |
117 | * which resulted in random data in an inode which looked enough | |
118 | * like a regular file for ext3 to try to delete it. Things | |
119 | * will go a bit crazy if that happens, but at least we should | |
120 | * try not to panic the whole kernel. */ | |
121 | if (needed < 2) | |
122 | needed = 2; | |
123 | ||
124 | /* But we need to bound the transaction so we don't overflow the | |
125 | * journal. */ | |
ae6ddcc5 | 126 | if (needed > EXT3_MAX_TRANS_DATA) |
1da177e4 LT |
127 | needed = EXT3_MAX_TRANS_DATA; |
128 | ||
1f54587b | 129 | return EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + needed; |
1da177e4 LT |
130 | } |
131 | ||
ae6ddcc5 | 132 | /* |
1da177e4 LT |
133 | * Truncate transactions can be complex and absolutely huge. So we need to |
134 | * be able to restart the transaction at a conventient checkpoint to make | |
135 | * sure we don't overflow the journal. | |
136 | * | |
137 | * start_transaction gets us a new handle for a truncate transaction, | |
138 | * and extend_transaction tries to extend the existing one a bit. If | |
139 | * extend fails, we need to propagate the failure up and restart the | |
ae6ddcc5 | 140 | * transaction in the top-level truncate loop. --sct |
1da177e4 | 141 | */ |
ae6ddcc5 | 142 | static handle_t *start_transaction(struct inode *inode) |
1da177e4 LT |
143 | { |
144 | handle_t *result; | |
145 | ||
146 | result = ext3_journal_start(inode, blocks_for_truncate(inode)); | |
147 | if (!IS_ERR(result)) | |
148 | return result; | |
149 | ||
150 | ext3_std_error(inode->i_sb, PTR_ERR(result)); | |
151 | return result; | |
152 | } | |
153 | ||
154 | /* | |
155 | * Try to extend this transaction for the purposes of truncation. | |
156 | * | |
157 | * Returns 0 if we managed to create more room. If we can't create more | |
158 | * room, and the transaction must be restarted we return 1. | |
159 | */ | |
160 | static int try_to_extend_transaction(handle_t *handle, struct inode *inode) | |
161 | { | |
162 | if (handle->h_buffer_credits > EXT3_RESERVE_TRANS_BLOCKS) | |
163 | return 0; | |
164 | if (!ext3_journal_extend(handle, blocks_for_truncate(inode))) | |
165 | return 0; | |
166 | return 1; | |
167 | } | |
168 | ||
169 | /* | |
170 | * Restart the transaction associated with *handle. This does a commit, | |
171 | * so before we call here everything must be consistently dirtied against | |
172 | * this transaction. | |
173 | */ | |
174 | static int ext3_journal_test_restart(handle_t *handle, struct inode *inode) | |
175 | { | |
176 | jbd_debug(2, "restarting handle %p\n", handle); | |
177 | return ext3_journal_restart(handle, blocks_for_truncate(inode)); | |
178 | } | |
179 | ||
180 | /* | |
181 | * Called at the last iput() if i_nlink is zero. | |
182 | */ | |
183 | void ext3_delete_inode (struct inode * inode) | |
184 | { | |
185 | handle_t *handle; | |
186 | ||
fef26658 MF |
187 | truncate_inode_pages(&inode->i_data, 0); |
188 | ||
1da177e4 LT |
189 | if (is_bad_inode(inode)) |
190 | goto no_delete; | |
191 | ||
192 | handle = start_transaction(inode); | |
193 | if (IS_ERR(handle)) { | |
d6859bfc AM |
194 | /* |
195 | * If we're going to skip the normal cleanup, we still need to | |
196 | * make sure that the in-core orphan linked list is properly | |
197 | * cleaned up. | |
198 | */ | |
1da177e4 LT |
199 | ext3_orphan_del(NULL, inode); |
200 | goto no_delete; | |
201 | } | |
202 | ||
203 | if (IS_SYNC(inode)) | |
204 | handle->h_sync = 1; | |
205 | inode->i_size = 0; | |
206 | if (inode->i_blocks) | |
207 | ext3_truncate(inode); | |
208 | /* | |
209 | * Kill off the orphan record which ext3_truncate created. | |
210 | * AKPM: I think this can be inside the above `if'. | |
211 | * Note that ext3_orphan_del() has to be able to cope with the | |
212 | * deletion of a non-existent orphan - this is because we don't | |
213 | * know if ext3_truncate() actually created an orphan record. | |
214 | * (Well, we could do this if we need to, but heck - it works) | |
215 | */ | |
216 | ext3_orphan_del(handle, inode); | |
217 | EXT3_I(inode)->i_dtime = get_seconds(); | |
218 | ||
ae6ddcc5 | 219 | /* |
1da177e4 LT |
220 | * One subtle ordering requirement: if anything has gone wrong |
221 | * (transaction abort, IO errors, whatever), then we can still | |
222 | * do these next steps (the fs will already have been marked as | |
223 | * having errors), but we can't free the inode if the mark_dirty | |
ae6ddcc5 | 224 | * fails. |
1da177e4 LT |
225 | */ |
226 | if (ext3_mark_inode_dirty(handle, inode)) | |
227 | /* If that failed, just do the required in-core inode clear. */ | |
228 | clear_inode(inode); | |
229 | else | |
230 | ext3_free_inode(handle, inode); | |
231 | ext3_journal_stop(handle); | |
232 | return; | |
233 | no_delete: | |
234 | clear_inode(inode); /* We must guarantee clearing of inode... */ | |
235 | } | |
236 | ||
1da177e4 LT |
237 | typedef struct { |
238 | __le32 *p; | |
239 | __le32 key; | |
240 | struct buffer_head *bh; | |
241 | } Indirect; | |
242 | ||
243 | static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) | |
244 | { | |
245 | p->key = *(p->p = v); | |
246 | p->bh = bh; | |
247 | } | |
248 | ||
d6859bfc | 249 | static int verify_chain(Indirect *from, Indirect *to) |
1da177e4 LT |
250 | { |
251 | while (from <= to && from->key == *from->p) | |
252 | from++; | |
253 | return (from > to); | |
254 | } | |
255 | ||
256 | /** | |
257 | * ext3_block_to_path - parse the block number into array of offsets | |
258 | * @inode: inode in question (we are only interested in its superblock) | |
259 | * @i_block: block number to be parsed | |
260 | * @offsets: array to store the offsets in | |
261 | * @boundary: set this non-zero if the referred-to block is likely to be | |
262 | * followed (on disk) by an indirect block. | |
263 | * | |
264 | * To store the locations of file's data ext3 uses a data structure common | |
265 | * for UNIX filesystems - tree of pointers anchored in the inode, with | |
266 | * data blocks at leaves and indirect blocks in intermediate nodes. | |
267 | * This function translates the block number into path in that tree - | |
268 | * return value is the path length and @offsets[n] is the offset of | |
269 | * pointer to (n+1)th node in the nth one. If @block is out of range | |
270 | * (negative or too large) warning is printed and zero returned. | |
271 | * | |
272 | * Note: function doesn't find node addresses, so no IO is needed. All | |
273 | * we need to know is the capacity of indirect blocks (taken from the | |
274 | * inode->i_sb). | |
275 | */ | |
276 | ||
277 | /* | |
278 | * Portability note: the last comparison (check that we fit into triple | |
279 | * indirect block) is spelled differently, because otherwise on an | |
280 | * architecture with 32-bit longs and 8Kb pages we might get into trouble | |
281 | * if our filesystem had 8Kb blocks. We might use long long, but that would | |
282 | * kill us on x86. Oh, well, at least the sign propagation does not matter - | |
283 | * i_block would have to be negative in the very beginning, so we would not | |
284 | * get there at all. | |
285 | */ | |
286 | ||
287 | static int ext3_block_to_path(struct inode *inode, | |
288 | long i_block, int offsets[4], int *boundary) | |
289 | { | |
290 | int ptrs = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
291 | int ptrs_bits = EXT3_ADDR_PER_BLOCK_BITS(inode->i_sb); | |
292 | const long direct_blocks = EXT3_NDIR_BLOCKS, | |
293 | indirect_blocks = ptrs, | |
294 | double_blocks = (1 << (ptrs_bits * 2)); | |
295 | int n = 0; | |
296 | int final = 0; | |
297 | ||
298 | if (i_block < 0) { | |
299 | ext3_warning (inode->i_sb, "ext3_block_to_path", "block < 0"); | |
300 | } else if (i_block < direct_blocks) { | |
301 | offsets[n++] = i_block; | |
302 | final = direct_blocks; | |
303 | } else if ( (i_block -= direct_blocks) < indirect_blocks) { | |
304 | offsets[n++] = EXT3_IND_BLOCK; | |
305 | offsets[n++] = i_block; | |
306 | final = ptrs; | |
307 | } else if ((i_block -= indirect_blocks) < double_blocks) { | |
308 | offsets[n++] = EXT3_DIND_BLOCK; | |
309 | offsets[n++] = i_block >> ptrs_bits; | |
310 | offsets[n++] = i_block & (ptrs - 1); | |
311 | final = ptrs; | |
312 | } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { | |
313 | offsets[n++] = EXT3_TIND_BLOCK; | |
314 | offsets[n++] = i_block >> (ptrs_bits * 2); | |
315 | offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); | |
316 | offsets[n++] = i_block & (ptrs - 1); | |
317 | final = ptrs; | |
318 | } else { | |
d6859bfc | 319 | ext3_warning(inode->i_sb, "ext3_block_to_path", "block > big"); |
1da177e4 LT |
320 | } |
321 | if (boundary) | |
89747d36 | 322 | *boundary = final - 1 - (i_block & (ptrs - 1)); |
1da177e4 LT |
323 | return n; |
324 | } | |
325 | ||
326 | /** | |
327 | * ext3_get_branch - read the chain of indirect blocks leading to data | |
328 | * @inode: inode in question | |
329 | * @depth: depth of the chain (1 - direct pointer, etc.) | |
330 | * @offsets: offsets of pointers in inode/indirect blocks | |
331 | * @chain: place to store the result | |
332 | * @err: here we store the error value | |
333 | * | |
334 | * Function fills the array of triples <key, p, bh> and returns %NULL | |
335 | * if everything went OK or the pointer to the last filled triple | |
336 | * (incomplete one) otherwise. Upon the return chain[i].key contains | |
337 | * the number of (i+1)-th block in the chain (as it is stored in memory, | |
338 | * i.e. little-endian 32-bit), chain[i].p contains the address of that | |
339 | * number (it points into struct inode for i==0 and into the bh->b_data | |
340 | * for i>0) and chain[i].bh points to the buffer_head of i-th indirect | |
341 | * block for i>0 and NULL for i==0. In other words, it holds the block | |
342 | * numbers of the chain, addresses they were taken from (and where we can | |
343 | * verify that chain did not change) and buffer_heads hosting these | |
344 | * numbers. | |
345 | * | |
346 | * Function stops when it stumbles upon zero pointer (absent block) | |
347 | * (pointer to last triple returned, *@err == 0) | |
348 | * or when it gets an IO error reading an indirect block | |
349 | * (ditto, *@err == -EIO) | |
350 | * or when it notices that chain had been changed while it was reading | |
351 | * (ditto, *@err == -EAGAIN) | |
352 | * or when it reads all @depth-1 indirect blocks successfully and finds | |
353 | * the whole chain, all way to the data (returns %NULL, *err == 0). | |
354 | */ | |
355 | static Indirect *ext3_get_branch(struct inode *inode, int depth, int *offsets, | |
356 | Indirect chain[4], int *err) | |
357 | { | |
358 | struct super_block *sb = inode->i_sb; | |
359 | Indirect *p = chain; | |
360 | struct buffer_head *bh; | |
361 | ||
362 | *err = 0; | |
363 | /* i_data is not going away, no lock needed */ | |
364 | add_chain (chain, NULL, EXT3_I(inode)->i_data + *offsets); | |
365 | if (!p->key) | |
366 | goto no_block; | |
367 | while (--depth) { | |
368 | bh = sb_bread(sb, le32_to_cpu(p->key)); | |
369 | if (!bh) | |
370 | goto failure; | |
371 | /* Reader: pointers */ | |
372 | if (!verify_chain(chain, p)) | |
373 | goto changed; | |
374 | add_chain(++p, bh, (__le32*)bh->b_data + *++offsets); | |
375 | /* Reader: end */ | |
376 | if (!p->key) | |
377 | goto no_block; | |
378 | } | |
379 | return NULL; | |
380 | ||
381 | changed: | |
382 | brelse(bh); | |
383 | *err = -EAGAIN; | |
384 | goto no_block; | |
385 | failure: | |
386 | *err = -EIO; | |
387 | no_block: | |
388 | return p; | |
389 | } | |
390 | ||
391 | /** | |
392 | * ext3_find_near - find a place for allocation with sufficient locality | |
393 | * @inode: owner | |
394 | * @ind: descriptor of indirect block. | |
395 | * | |
1cc8dcf5 | 396 | * This function returns the preferred place for block allocation. |
1da177e4 LT |
397 | * It is used when heuristic for sequential allocation fails. |
398 | * Rules are: | |
399 | * + if there is a block to the left of our position - allocate near it. | |
400 | * + if pointer will live in indirect block - allocate near that block. | |
401 | * + if pointer will live in inode - allocate in the same | |
ae6ddcc5 | 402 | * cylinder group. |
1da177e4 LT |
403 | * |
404 | * In the latter case we colour the starting block by the callers PID to | |
405 | * prevent it from clashing with concurrent allocations for a different inode | |
406 | * in the same block group. The PID is used here so that functionally related | |
407 | * files will be close-by on-disk. | |
408 | * | |
409 | * Caller must make sure that @ind is valid and will stay that way. | |
410 | */ | |
43d23f90 | 411 | static ext3_fsblk_t ext3_find_near(struct inode *inode, Indirect *ind) |
1da177e4 LT |
412 | { |
413 | struct ext3_inode_info *ei = EXT3_I(inode); | |
414 | __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data; | |
415 | __le32 *p; | |
43d23f90 MC |
416 | ext3_fsblk_t bg_start; |
417 | ext3_grpblk_t colour; | |
1da177e4 LT |
418 | |
419 | /* Try to find previous block */ | |
d6859bfc | 420 | for (p = ind->p - 1; p >= start; p--) { |
1da177e4 LT |
421 | if (*p) |
422 | return le32_to_cpu(*p); | |
d6859bfc | 423 | } |
1da177e4 LT |
424 | |
425 | /* No such thing, so let's try location of indirect block */ | |
426 | if (ind->bh) | |
427 | return ind->bh->b_blocknr; | |
428 | ||
429 | /* | |
d6859bfc AM |
430 | * It is going to be referred to from the inode itself? OK, just put it |
431 | * into the same cylinder group then. | |
1da177e4 | 432 | */ |
43d23f90 | 433 | bg_start = ext3_group_first_block_no(inode->i_sb, ei->i_block_group); |
1da177e4 LT |
434 | colour = (current->pid % 16) * |
435 | (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16); | |
436 | return bg_start + colour; | |
437 | } | |
438 | ||
439 | /** | |
1cc8dcf5 | 440 | * ext3_find_goal - find a preferred place for allocation. |
1da177e4 LT |
441 | * @inode: owner |
442 | * @block: block we want | |
1da177e4 | 443 | * @partial: pointer to the last triple within a chain |
1da177e4 | 444 | * |
1cc8dcf5 | 445 | * Normally this function find the preferred place for block allocation, |
fb01bfda | 446 | * returns it. |
1da177e4 LT |
447 | */ |
448 | ||
43d23f90 | 449 | static ext3_fsblk_t ext3_find_goal(struct inode *inode, long block, |
fb01bfda | 450 | Indirect *partial) |
1da177e4 | 451 | { |
d6859bfc AM |
452 | struct ext3_block_alloc_info *block_i; |
453 | ||
454 | block_i = EXT3_I(inode)->i_block_alloc_info; | |
1da177e4 LT |
455 | |
456 | /* | |
457 | * try the heuristic for sequential allocation, | |
458 | * failing that at least try to get decent locality. | |
459 | */ | |
460 | if (block_i && (block == block_i->last_alloc_logical_block + 1) | |
461 | && (block_i->last_alloc_physical_block != 0)) { | |
fe55c452 | 462 | return block_i->last_alloc_physical_block + 1; |
1da177e4 LT |
463 | } |
464 | ||
fe55c452 | 465 | return ext3_find_near(inode, partial); |
1da177e4 | 466 | } |
d6859bfc | 467 | |
b47b2478 MC |
468 | /** |
469 | * ext3_blks_to_allocate: Look up the block map and count the number | |
470 | * of direct blocks need to be allocated for the given branch. | |
471 | * | |
e9ad5620 | 472 | * @branch: chain of indirect blocks |
b47b2478 MC |
473 | * @k: number of blocks need for indirect blocks |
474 | * @blks: number of data blocks to be mapped. | |
475 | * @blocks_to_boundary: the offset in the indirect block | |
476 | * | |
477 | * return the total number of blocks to be allocate, including the | |
478 | * direct and indirect blocks. | |
479 | */ | |
d6859bfc | 480 | static int ext3_blks_to_allocate(Indirect *branch, int k, unsigned long blks, |
b47b2478 MC |
481 | int blocks_to_boundary) |
482 | { | |
483 | unsigned long count = 0; | |
484 | ||
485 | /* | |
486 | * Simple case, [t,d]Indirect block(s) has not allocated yet | |
487 | * then it's clear blocks on that path have not allocated | |
488 | */ | |
489 | if (k > 0) { | |
d6859bfc | 490 | /* right now we don't handle cross boundary allocation */ |
b47b2478 MC |
491 | if (blks < blocks_to_boundary + 1) |
492 | count += blks; | |
493 | else | |
494 | count += blocks_to_boundary + 1; | |
495 | return count; | |
496 | } | |
497 | ||
498 | count++; | |
499 | while (count < blks && count <= blocks_to_boundary && | |
500 | le32_to_cpu(*(branch[0].p + count)) == 0) { | |
501 | count++; | |
502 | } | |
503 | return count; | |
504 | } | |
505 | ||
506 | /** | |
507 | * ext3_alloc_blocks: multiple allocate blocks needed for a branch | |
508 | * @indirect_blks: the number of blocks need to allocate for indirect | |
509 | * blocks | |
510 | * | |
511 | * @new_blocks: on return it will store the new block numbers for | |
512 | * the indirect blocks(if needed) and the first direct block, | |
513 | * @blks: on return it will store the total number of allocated | |
514 | * direct blocks | |
515 | */ | |
516 | static int ext3_alloc_blocks(handle_t *handle, struct inode *inode, | |
43d23f90 MC |
517 | ext3_fsblk_t goal, int indirect_blks, int blks, |
518 | ext3_fsblk_t new_blocks[4], int *err) | |
b47b2478 MC |
519 | { |
520 | int target, i; | |
521 | unsigned long count = 0; | |
522 | int index = 0; | |
43d23f90 | 523 | ext3_fsblk_t current_block = 0; |
b47b2478 MC |
524 | int ret = 0; |
525 | ||
526 | /* | |
527 | * Here we try to allocate the requested multiple blocks at once, | |
528 | * on a best-effort basis. | |
529 | * To build a branch, we should allocate blocks for | |
530 | * the indirect blocks(if not allocated yet), and at least | |
531 | * the first direct block of this branch. That's the | |
532 | * minimum number of blocks need to allocate(required) | |
533 | */ | |
534 | target = blks + indirect_blks; | |
535 | ||
536 | while (1) { | |
537 | count = target; | |
538 | /* allocating blocks for indirect blocks and direct blocks */ | |
d6859bfc | 539 | current_block = ext3_new_blocks(handle,inode,goal,&count,err); |
b47b2478 MC |
540 | if (*err) |
541 | goto failed_out; | |
542 | ||
543 | target -= count; | |
544 | /* allocate blocks for indirect blocks */ | |
545 | while (index < indirect_blks && count) { | |
546 | new_blocks[index++] = current_block++; | |
547 | count--; | |
548 | } | |
549 | ||
550 | if (count > 0) | |
551 | break; | |
552 | } | |
553 | ||
554 | /* save the new block number for the first direct block */ | |
555 | new_blocks[index] = current_block; | |
556 | ||
557 | /* total number of blocks allocated for direct blocks */ | |
558 | ret = count; | |
559 | *err = 0; | |
560 | return ret; | |
561 | failed_out: | |
562 | for (i = 0; i <index; i++) | |
563 | ext3_free_blocks(handle, inode, new_blocks[i], 1); | |
564 | return ret; | |
565 | } | |
1da177e4 LT |
566 | |
567 | /** | |
568 | * ext3_alloc_branch - allocate and set up a chain of blocks. | |
569 | * @inode: owner | |
b47b2478 MC |
570 | * @indirect_blks: number of allocated indirect blocks |
571 | * @blks: number of allocated direct blocks | |
1da177e4 LT |
572 | * @offsets: offsets (in the blocks) to store the pointers to next. |
573 | * @branch: place to store the chain in. | |
574 | * | |
b47b2478 | 575 | * This function allocates blocks, zeroes out all but the last one, |
1da177e4 LT |
576 | * links them into chain and (if we are synchronous) writes them to disk. |
577 | * In other words, it prepares a branch that can be spliced onto the | |
578 | * inode. It stores the information about that chain in the branch[], in | |
579 | * the same format as ext3_get_branch() would do. We are calling it after | |
580 | * we had read the existing part of chain and partial points to the last | |
581 | * triple of that (one with zero ->key). Upon the exit we have the same | |
5b116879 | 582 | * picture as after the successful ext3_get_block(), except that in one |
1da177e4 LT |
583 | * place chain is disconnected - *branch->p is still zero (we did not |
584 | * set the last link), but branch->key contains the number that should | |
585 | * be placed into *branch->p to fill that gap. | |
586 | * | |
587 | * If allocation fails we free all blocks we've allocated (and forget | |
588 | * their buffer_heads) and return the error value the from failed | |
589 | * ext3_alloc_block() (normally -ENOSPC). Otherwise we set the chain | |
590 | * as described above and return 0. | |
591 | */ | |
1da177e4 | 592 | static int ext3_alloc_branch(handle_t *handle, struct inode *inode, |
43d23f90 | 593 | int indirect_blks, int *blks, ext3_fsblk_t goal, |
b47b2478 | 594 | int *offsets, Indirect *branch) |
1da177e4 LT |
595 | { |
596 | int blocksize = inode->i_sb->s_blocksize; | |
b47b2478 | 597 | int i, n = 0; |
1da177e4 | 598 | int err = 0; |
b47b2478 MC |
599 | struct buffer_head *bh; |
600 | int num; | |
43d23f90 MC |
601 | ext3_fsblk_t new_blocks[4]; |
602 | ext3_fsblk_t current_block; | |
1da177e4 | 603 | |
b47b2478 MC |
604 | num = ext3_alloc_blocks(handle, inode, goal, indirect_blks, |
605 | *blks, new_blocks, &err); | |
606 | if (err) | |
607 | return err; | |
1da177e4 | 608 | |
b47b2478 MC |
609 | branch[0].key = cpu_to_le32(new_blocks[0]); |
610 | /* | |
611 | * metadata blocks and data blocks are allocated. | |
612 | */ | |
613 | for (n = 1; n <= indirect_blks; n++) { | |
614 | /* | |
615 | * Get buffer_head for parent block, zero it out | |
616 | * and set the pointer to new one, then send | |
617 | * parent to disk. | |
618 | */ | |
619 | bh = sb_getblk(inode->i_sb, new_blocks[n-1]); | |
620 | branch[n].bh = bh; | |
621 | lock_buffer(bh); | |
622 | BUFFER_TRACE(bh, "call get_create_access"); | |
623 | err = ext3_journal_get_create_access(handle, bh); | |
624 | if (err) { | |
1da177e4 | 625 | unlock_buffer(bh); |
b47b2478 MC |
626 | brelse(bh); |
627 | goto failed; | |
628 | } | |
1da177e4 | 629 | |
b47b2478 MC |
630 | memset(bh->b_data, 0, blocksize); |
631 | branch[n].p = (__le32 *) bh->b_data + offsets[n]; | |
632 | branch[n].key = cpu_to_le32(new_blocks[n]); | |
633 | *branch[n].p = branch[n].key; | |
634 | if ( n == indirect_blks) { | |
635 | current_block = new_blocks[n]; | |
636 | /* | |
637 | * End of chain, update the last new metablock of | |
638 | * the chain to point to the new allocated | |
639 | * data blocks numbers | |
640 | */ | |
641 | for (i=1; i < num; i++) | |
642 | *(branch[n].p + i) = cpu_to_le32(++current_block); | |
1da177e4 | 643 | } |
b47b2478 MC |
644 | BUFFER_TRACE(bh, "marking uptodate"); |
645 | set_buffer_uptodate(bh); | |
646 | unlock_buffer(bh); | |
1da177e4 | 647 | |
b47b2478 MC |
648 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); |
649 | err = ext3_journal_dirty_metadata(handle, bh); | |
650 | if (err) | |
651 | goto failed; | |
652 | } | |
653 | *blks = num; | |
654 | return err; | |
655 | failed: | |
1da177e4 | 656 | /* Allocation failed, free what we already allocated */ |
b47b2478 | 657 | for (i = 1; i <= n ; i++) { |
1da177e4 LT |
658 | BUFFER_TRACE(branch[i].bh, "call journal_forget"); |
659 | ext3_journal_forget(handle, branch[i].bh); | |
660 | } | |
b47b2478 MC |
661 | for (i = 0; i <indirect_blks; i++) |
662 | ext3_free_blocks(handle, inode, new_blocks[i], 1); | |
663 | ||
664 | ext3_free_blocks(handle, inode, new_blocks[i], num); | |
665 | ||
1da177e4 LT |
666 | return err; |
667 | } | |
668 | ||
669 | /** | |
d6859bfc AM |
670 | * ext3_splice_branch - splice the allocated branch onto inode. |
671 | * @inode: owner | |
672 | * @block: (logical) number of block we are adding | |
673 | * @chain: chain of indirect blocks (with a missing link - see | |
674 | * ext3_alloc_branch) | |
675 | * @where: location of missing link | |
676 | * @num: number of indirect blocks we are adding | |
677 | * @blks: number of direct blocks we are adding | |
678 | * | |
679 | * This function fills the missing link and does all housekeeping needed in | |
680 | * inode (->i_blocks, etc.). In case of success we end up with the full | |
681 | * chain to new block and return 0. | |
1da177e4 | 682 | */ |
d6859bfc AM |
683 | static int ext3_splice_branch(handle_t *handle, struct inode *inode, |
684 | long block, Indirect *where, int num, int blks) | |
1da177e4 LT |
685 | { |
686 | int i; | |
687 | int err = 0; | |
d6859bfc | 688 | struct ext3_block_alloc_info *block_i; |
43d23f90 | 689 | ext3_fsblk_t current_block; |
d6859bfc AM |
690 | |
691 | block_i = EXT3_I(inode)->i_block_alloc_info; | |
1da177e4 LT |
692 | /* |
693 | * If we're splicing into a [td]indirect block (as opposed to the | |
694 | * inode) then we need to get write access to the [td]indirect block | |
695 | * before the splice. | |
696 | */ | |
697 | if (where->bh) { | |
698 | BUFFER_TRACE(where->bh, "get_write_access"); | |
699 | err = ext3_journal_get_write_access(handle, where->bh); | |
700 | if (err) | |
701 | goto err_out; | |
702 | } | |
1da177e4 LT |
703 | /* That's it */ |
704 | ||
705 | *where->p = where->key; | |
d6859bfc AM |
706 | |
707 | /* | |
708 | * Update the host buffer_head or inode to point to more just allocated | |
709 | * direct blocks blocks | |
710 | */ | |
b47b2478 | 711 | if (num == 0 && blks > 1) { |
5dea5176 | 712 | current_block = le32_to_cpu(where->key) + 1; |
b47b2478 MC |
713 | for (i = 1; i < blks; i++) |
714 | *(where->p + i ) = cpu_to_le32(current_block++); | |
715 | } | |
1da177e4 LT |
716 | |
717 | /* | |
718 | * update the most recently allocated logical & physical block | |
719 | * in i_block_alloc_info, to assist find the proper goal block for next | |
720 | * allocation | |
721 | */ | |
722 | if (block_i) { | |
b47b2478 | 723 | block_i->last_alloc_logical_block = block + blks - 1; |
d6859bfc | 724 | block_i->last_alloc_physical_block = |
5dea5176 | 725 | le32_to_cpu(where[num].key) + blks - 1; |
1da177e4 LT |
726 | } |
727 | ||
728 | /* We are done with atomic stuff, now do the rest of housekeeping */ | |
729 | ||
730 | inode->i_ctime = CURRENT_TIME_SEC; | |
731 | ext3_mark_inode_dirty(handle, inode); | |
732 | ||
733 | /* had we spliced it onto indirect block? */ | |
734 | if (where->bh) { | |
735 | /* | |
d6859bfc | 736 | * If we spliced it onto an indirect block, we haven't |
1da177e4 LT |
737 | * altered the inode. Note however that if it is being spliced |
738 | * onto an indirect block at the very end of the file (the | |
739 | * file is growing) then we *will* alter the inode to reflect | |
740 | * the new i_size. But that is not done here - it is done in | |
741 | * generic_commit_write->__mark_inode_dirty->ext3_dirty_inode. | |
742 | */ | |
743 | jbd_debug(5, "splicing indirect only\n"); | |
744 | BUFFER_TRACE(where->bh, "call ext3_journal_dirty_metadata"); | |
745 | err = ext3_journal_dirty_metadata(handle, where->bh); | |
ae6ddcc5 | 746 | if (err) |
1da177e4 LT |
747 | goto err_out; |
748 | } else { | |
749 | /* | |
750 | * OK, we spliced it into the inode itself on a direct block. | |
751 | * Inode was dirtied above. | |
752 | */ | |
753 | jbd_debug(5, "splicing direct\n"); | |
754 | } | |
755 | return err; | |
756 | ||
1da177e4 | 757 | err_out: |
b47b2478 | 758 | for (i = 1; i <= num; i++) { |
1da177e4 LT |
759 | BUFFER_TRACE(where[i].bh, "call journal_forget"); |
760 | ext3_journal_forget(handle, where[i].bh); | |
d6859bfc | 761 | ext3_free_blocks(handle,inode,le32_to_cpu(where[i-1].key),1); |
1da177e4 | 762 | } |
b47b2478 MC |
763 | ext3_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks); |
764 | ||
1da177e4 LT |
765 | return err; |
766 | } | |
767 | ||
768 | /* | |
769 | * Allocation strategy is simple: if we have to allocate something, we will | |
770 | * have to go the whole way to leaf. So let's do it before attaching anything | |
771 | * to tree, set linkage between the newborn blocks, write them if sync is | |
772 | * required, recheck the path, free and repeat if check fails, otherwise | |
773 | * set the last missing link (that will protect us from any truncate-generated | |
774 | * removals - all blocks on the path are immune now) and possibly force the | |
775 | * write on the parent block. | |
776 | * That has a nice additional property: no special recovery from the failed | |
777 | * allocations is needed - we simply release blocks and do not touch anything | |
778 | * reachable from inode. | |
779 | * | |
d6859bfc | 780 | * `handle' can be NULL if create == 0. |
1da177e4 LT |
781 | * |
782 | * The BKL may not be held on entry here. Be sure to take it early. | |
89747d36 MC |
783 | * return > 0, # of blocks mapped or allocated. |
784 | * return = 0, if plain lookup failed. | |
785 | * return < 0, error case. | |
1da177e4 | 786 | */ |
d6859bfc AM |
787 | int ext3_get_blocks_handle(handle_t *handle, struct inode *inode, |
788 | sector_t iblock, unsigned long maxblocks, | |
789 | struct buffer_head *bh_result, | |
89747d36 | 790 | int create, int extend_disksize) |
1da177e4 LT |
791 | { |
792 | int err = -EIO; | |
793 | int offsets[4]; | |
794 | Indirect chain[4]; | |
795 | Indirect *partial; | |
43d23f90 | 796 | ext3_fsblk_t goal; |
b47b2478 | 797 | int indirect_blks; |
89747d36 MC |
798 | int blocks_to_boundary = 0; |
799 | int depth; | |
1da177e4 | 800 | struct ext3_inode_info *ei = EXT3_I(inode); |
89747d36 | 801 | int count = 0; |
43d23f90 | 802 | ext3_fsblk_t first_block = 0; |
89747d36 | 803 | |
1da177e4 LT |
804 | |
805 | J_ASSERT(handle != NULL || create == 0); | |
d6859bfc | 806 | depth = ext3_block_to_path(inode,iblock,offsets,&blocks_to_boundary); |
1da177e4 LT |
807 | |
808 | if (depth == 0) | |
809 | goto out; | |
810 | ||
1da177e4 LT |
811 | partial = ext3_get_branch(inode, depth, offsets, chain, &err); |
812 | ||
813 | /* Simplest case - block found, no allocation needed */ | |
814 | if (!partial) { | |
5dea5176 | 815 | first_block = le32_to_cpu(chain[depth - 1].key); |
1da177e4 | 816 | clear_buffer_new(bh_result); |
89747d36 MC |
817 | count++; |
818 | /*map more blocks*/ | |
819 | while (count < maxblocks && count <= blocks_to_boundary) { | |
43d23f90 | 820 | ext3_fsblk_t blk; |
5dea5176 | 821 | |
89747d36 MC |
822 | if (!verify_chain(chain, partial)) { |
823 | /* | |
824 | * Indirect block might be removed by | |
825 | * truncate while we were reading it. | |
826 | * Handling of that case: forget what we've | |
827 | * got now. Flag the err as EAGAIN, so it | |
828 | * will reread. | |
829 | */ | |
830 | err = -EAGAIN; | |
831 | count = 0; | |
832 | break; | |
833 | } | |
5dea5176 MC |
834 | blk = le32_to_cpu(*(chain[depth-1].p + count)); |
835 | ||
836 | if (blk == first_block + count) | |
89747d36 MC |
837 | count++; |
838 | else | |
839 | break; | |
840 | } | |
841 | if (err != -EAGAIN) | |
842 | goto got_it; | |
1da177e4 LT |
843 | } |
844 | ||
845 | /* Next simple case - plain lookup or failed read of indirect block */ | |
fe55c452 MC |
846 | if (!create || err == -EIO) |
847 | goto cleanup; | |
848 | ||
97461518 | 849 | mutex_lock(&ei->truncate_mutex); |
fe55c452 MC |
850 | |
851 | /* | |
852 | * If the indirect block is missing while we are reading | |
853 | * the chain(ext3_get_branch() returns -EAGAIN err), or | |
854 | * if the chain has been changed after we grab the semaphore, | |
855 | * (either because another process truncated this branch, or | |
856 | * another get_block allocated this branch) re-grab the chain to see if | |
857 | * the request block has been allocated or not. | |
858 | * | |
859 | * Since we already block the truncate/other get_block | |
860 | * at this point, we will have the current copy of the chain when we | |
861 | * splice the branch into the tree. | |
862 | */ | |
863 | if (err == -EAGAIN || !verify_chain(chain, partial)) { | |
1da177e4 | 864 | while (partial > chain) { |
1da177e4 LT |
865 | brelse(partial->bh); |
866 | partial--; | |
867 | } | |
fe55c452 MC |
868 | partial = ext3_get_branch(inode, depth, offsets, chain, &err); |
869 | if (!partial) { | |
89747d36 | 870 | count++; |
97461518 | 871 | mutex_unlock(&ei->truncate_mutex); |
fe55c452 MC |
872 | if (err) |
873 | goto cleanup; | |
874 | clear_buffer_new(bh_result); | |
875 | goto got_it; | |
876 | } | |
1da177e4 LT |
877 | } |
878 | ||
879 | /* | |
fe55c452 MC |
880 | * Okay, we need to do block allocation. Lazily initialize the block |
881 | * allocation info here if necessary | |
882 | */ | |
883 | if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info)) | |
1da177e4 | 884 | ext3_init_block_alloc_info(inode); |
1da177e4 | 885 | |
fb01bfda | 886 | goal = ext3_find_goal(inode, iblock, partial); |
1da177e4 | 887 | |
b47b2478 MC |
888 | /* the number of blocks need to allocate for [d,t]indirect blocks */ |
889 | indirect_blks = (chain + depth) - partial - 1; | |
1da177e4 | 890 | |
b47b2478 MC |
891 | /* |
892 | * Next look up the indirect map to count the totoal number of | |
893 | * direct blocks to allocate for this branch. | |
894 | */ | |
895 | count = ext3_blks_to_allocate(partial, indirect_blks, | |
896 | maxblocks, blocks_to_boundary); | |
1da177e4 LT |
897 | /* |
898 | * Block out ext3_truncate while we alter the tree | |
899 | */ | |
b47b2478 | 900 | err = ext3_alloc_branch(handle, inode, indirect_blks, &count, goal, |
fe55c452 | 901 | offsets + (partial - chain), partial); |
1da177e4 | 902 | |
fe55c452 MC |
903 | /* |
904 | * The ext3_splice_branch call will free and forget any buffers | |
1da177e4 LT |
905 | * on the new chain if there is a failure, but that risks using |
906 | * up transaction credits, especially for bitmaps where the | |
907 | * credits cannot be returned. Can we handle this somehow? We | |
fe55c452 MC |
908 | * may need to return -EAGAIN upwards in the worst case. --sct |
909 | */ | |
1da177e4 | 910 | if (!err) |
b47b2478 MC |
911 | err = ext3_splice_branch(handle, inode, iblock, |
912 | partial, indirect_blks, count); | |
fe55c452 | 913 | /* |
97461518 | 914 | * i_disksize growing is protected by truncate_mutex. Don't forget to |
fe55c452 MC |
915 | * protect it if you're about to implement concurrent |
916 | * ext3_get_block() -bzzz | |
917 | */ | |
1da177e4 LT |
918 | if (!err && extend_disksize && inode->i_size > ei->i_disksize) |
919 | ei->i_disksize = inode->i_size; | |
97461518 | 920 | mutex_unlock(&ei->truncate_mutex); |
1da177e4 LT |
921 | if (err) |
922 | goto cleanup; | |
923 | ||
924 | set_buffer_new(bh_result); | |
fe55c452 MC |
925 | got_it: |
926 | map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); | |
20acaa18 | 927 | if (count > blocks_to_boundary) |
fe55c452 | 928 | set_buffer_boundary(bh_result); |
89747d36 | 929 | err = count; |
fe55c452 MC |
930 | /* Clean up and exit */ |
931 | partial = chain + depth - 1; /* the whole chain */ | |
932 | cleanup: | |
1da177e4 | 933 | while (partial > chain) { |
fe55c452 | 934 | BUFFER_TRACE(partial->bh, "call brelse"); |
1da177e4 LT |
935 | brelse(partial->bh); |
936 | partial--; | |
937 | } | |
fe55c452 MC |
938 | BUFFER_TRACE(bh_result, "returned"); |
939 | out: | |
940 | return err; | |
1da177e4 LT |
941 | } |
942 | ||
bd1939de JK |
943 | /* Maximum number of blocks we map for direct IO at once. */ |
944 | #define DIO_MAX_BLOCKS 4096 | |
945 | /* | |
946 | * Number of credits we need for writing DIO_MAX_BLOCKS: | |
947 | * We need sb + group descriptor + bitmap + inode -> 4 | |
948 | * For B blocks with A block pointers per block we need: | |
949 | * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect). | |
950 | * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25. | |
951 | */ | |
952 | #define DIO_CREDITS 25 | |
1da177e4 | 953 | |
f91a2ad2 BP |
954 | static int ext3_get_block(struct inode *inode, sector_t iblock, |
955 | struct buffer_head *bh_result, int create) | |
1da177e4 | 956 | { |
3e4fdaf8 | 957 | handle_t *handle = ext3_journal_current_handle(); |
bd1939de | 958 | int ret = 0, started = 0; |
1d8fa7a2 | 959 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; |
1da177e4 | 960 | |
bd1939de JK |
961 | if (create && !handle) { /* Direct IO write... */ |
962 | if (max_blocks > DIO_MAX_BLOCKS) | |
963 | max_blocks = DIO_MAX_BLOCKS; | |
964 | handle = ext3_journal_start(inode, DIO_CREDITS + | |
965 | 2 * EXT3_QUOTA_TRANS_BLOCKS(inode->i_sb)); | |
966 | if (IS_ERR(handle)) { | |
1da177e4 | 967 | ret = PTR_ERR(handle); |
bd1939de | 968 | goto out; |
1da177e4 | 969 | } |
bd1939de | 970 | started = 1; |
1da177e4 LT |
971 | } |
972 | ||
bd1939de | 973 | ret = ext3_get_blocks_handle(handle, inode, iblock, |
89747d36 | 974 | max_blocks, bh_result, create, 0); |
bd1939de JK |
975 | if (ret > 0) { |
976 | bh_result->b_size = (ret << inode->i_blkbits); | |
977 | ret = 0; | |
89747d36 | 978 | } |
bd1939de JK |
979 | if (started) |
980 | ext3_journal_stop(handle); | |
981 | out: | |
1da177e4 LT |
982 | return ret; |
983 | } | |
984 | ||
68c9d702 JB |
985 | int ext3_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, |
986 | u64 start, u64 len) | |
987 | { | |
988 | return generic_block_fiemap(inode, fieinfo, start, len, | |
989 | ext3_get_block); | |
990 | } | |
991 | ||
1da177e4 LT |
992 | /* |
993 | * `handle' can be NULL if create is zero | |
994 | */ | |
d6859bfc AM |
995 | struct buffer_head *ext3_getblk(handle_t *handle, struct inode *inode, |
996 | long block, int create, int *errp) | |
1da177e4 LT |
997 | { |
998 | struct buffer_head dummy; | |
999 | int fatal = 0, err; | |
1000 | ||
1001 | J_ASSERT(handle != NULL || create == 0); | |
1002 | ||
1003 | dummy.b_state = 0; | |
1004 | dummy.b_blocknr = -1000; | |
1005 | buffer_trace_init(&dummy.b_history); | |
89747d36 MC |
1006 | err = ext3_get_blocks_handle(handle, inode, block, 1, |
1007 | &dummy, create, 1); | |
3665d0e5 BP |
1008 | /* |
1009 | * ext3_get_blocks_handle() returns number of blocks | |
1010 | * mapped. 0 in case of a HOLE. | |
1011 | */ | |
1012 | if (err > 0) { | |
1013 | if (err > 1) | |
1014 | WARN_ON(1); | |
89747d36 | 1015 | err = 0; |
89747d36 MC |
1016 | } |
1017 | *errp = err; | |
1018 | if (!err && buffer_mapped(&dummy)) { | |
1da177e4 LT |
1019 | struct buffer_head *bh; |
1020 | bh = sb_getblk(inode->i_sb, dummy.b_blocknr); | |
2973dfdb GOC |
1021 | if (!bh) { |
1022 | *errp = -EIO; | |
1023 | goto err; | |
1024 | } | |
1da177e4 LT |
1025 | if (buffer_new(&dummy)) { |
1026 | J_ASSERT(create != 0); | |
c80544dc | 1027 | J_ASSERT(handle != NULL); |
1da177e4 | 1028 | |
d6859bfc AM |
1029 | /* |
1030 | * Now that we do not always journal data, we should | |
1031 | * keep in mind whether this should always journal the | |
1032 | * new buffer as metadata. For now, regular file | |
1033 | * writes use ext3_get_block instead, so it's not a | |
1034 | * problem. | |
1035 | */ | |
1da177e4 LT |
1036 | lock_buffer(bh); |
1037 | BUFFER_TRACE(bh, "call get_create_access"); | |
1038 | fatal = ext3_journal_get_create_access(handle, bh); | |
1039 | if (!fatal && !buffer_uptodate(bh)) { | |
d6859bfc | 1040 | memset(bh->b_data,0,inode->i_sb->s_blocksize); |
1da177e4 LT |
1041 | set_buffer_uptodate(bh); |
1042 | } | |
1043 | unlock_buffer(bh); | |
1044 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
1045 | err = ext3_journal_dirty_metadata(handle, bh); | |
1046 | if (!fatal) | |
1047 | fatal = err; | |
1048 | } else { | |
1049 | BUFFER_TRACE(bh, "not a new buffer"); | |
1050 | } | |
1051 | if (fatal) { | |
1052 | *errp = fatal; | |
1053 | brelse(bh); | |
1054 | bh = NULL; | |
1055 | } | |
1056 | return bh; | |
1057 | } | |
2973dfdb | 1058 | err: |
1da177e4 LT |
1059 | return NULL; |
1060 | } | |
1061 | ||
d6859bfc | 1062 | struct buffer_head *ext3_bread(handle_t *handle, struct inode *inode, |
1da177e4 LT |
1063 | int block, int create, int *err) |
1064 | { | |
1065 | struct buffer_head * bh; | |
1066 | ||
1067 | bh = ext3_getblk(handle, inode, block, create, err); | |
1068 | if (!bh) | |
1069 | return bh; | |
1070 | if (buffer_uptodate(bh)) | |
1071 | return bh; | |
caa38fb0 | 1072 | ll_rw_block(READ_META, 1, &bh); |
1da177e4 LT |
1073 | wait_on_buffer(bh); |
1074 | if (buffer_uptodate(bh)) | |
1075 | return bh; | |
1076 | put_bh(bh); | |
1077 | *err = -EIO; | |
1078 | return NULL; | |
1079 | } | |
1080 | ||
1081 | static int walk_page_buffers( handle_t *handle, | |
1082 | struct buffer_head *head, | |
1083 | unsigned from, | |
1084 | unsigned to, | |
1085 | int *partial, | |
1086 | int (*fn)( handle_t *handle, | |
1087 | struct buffer_head *bh)) | |
1088 | { | |
1089 | struct buffer_head *bh; | |
1090 | unsigned block_start, block_end; | |
1091 | unsigned blocksize = head->b_size; | |
1092 | int err, ret = 0; | |
1093 | struct buffer_head *next; | |
1094 | ||
1095 | for ( bh = head, block_start = 0; | |
1096 | ret == 0 && (bh != head || !block_start); | |
e9ad5620 | 1097 | block_start = block_end, bh = next) |
1da177e4 LT |
1098 | { |
1099 | next = bh->b_this_page; | |
1100 | block_end = block_start + blocksize; | |
1101 | if (block_end <= from || block_start >= to) { | |
1102 | if (partial && !buffer_uptodate(bh)) | |
1103 | *partial = 1; | |
1104 | continue; | |
1105 | } | |
1106 | err = (*fn)(handle, bh); | |
1107 | if (!ret) | |
1108 | ret = err; | |
1109 | } | |
1110 | return ret; | |
1111 | } | |
1112 | ||
1113 | /* | |
1114 | * To preserve ordering, it is essential that the hole instantiation and | |
1115 | * the data write be encapsulated in a single transaction. We cannot | |
1116 | * close off a transaction and start a new one between the ext3_get_block() | |
1117 | * and the commit_write(). So doing the journal_start at the start of | |
1118 | * prepare_write() is the right place. | |
1119 | * | |
1120 | * Also, this function can nest inside ext3_writepage() -> | |
1121 | * block_write_full_page(). In that case, we *know* that ext3_writepage() | |
1122 | * has generated enough buffer credits to do the whole page. So we won't | |
1123 | * block on the journal in that case, which is good, because the caller may | |
1124 | * be PF_MEMALLOC. | |
1125 | * | |
1126 | * By accident, ext3 can be reentered when a transaction is open via | |
1127 | * quota file writes. If we were to commit the transaction while thus | |
1128 | * reentered, there can be a deadlock - we would be holding a quota | |
1129 | * lock, and the commit would never complete if another thread had a | |
1130 | * transaction open and was blocking on the quota lock - a ranking | |
1131 | * violation. | |
1132 | * | |
1133 | * So what we do is to rely on the fact that journal_stop/journal_start | |
1134 | * will _not_ run commit under these circumstances because handle->h_ref | |
1135 | * is elevated. We'll still have enough credits for the tiny quotafile | |
ae6ddcc5 | 1136 | * write. |
1da177e4 | 1137 | */ |
d6859bfc AM |
1138 | static int do_journal_get_write_access(handle_t *handle, |
1139 | struct buffer_head *bh) | |
1da177e4 LT |
1140 | { |
1141 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1142 | return 0; | |
1143 | return ext3_journal_get_write_access(handle, bh); | |
1144 | } | |
1145 | ||
f4fc66a8 NP |
1146 | static int ext3_write_begin(struct file *file, struct address_space *mapping, |
1147 | loff_t pos, unsigned len, unsigned flags, | |
1148 | struct page **pagep, void **fsdata) | |
1da177e4 | 1149 | { |
f4fc66a8 | 1150 | struct inode *inode = mapping->host; |
1aa9b4b9 | 1151 | int ret, needed_blocks = ext3_writepage_trans_blocks(inode); |
1da177e4 LT |
1152 | handle_t *handle; |
1153 | int retries = 0; | |
f4fc66a8 NP |
1154 | struct page *page; |
1155 | pgoff_t index; | |
1156 | unsigned from, to; | |
1157 | ||
1158 | index = pos >> PAGE_CACHE_SHIFT; | |
1159 | from = pos & (PAGE_CACHE_SIZE - 1); | |
1160 | to = from + len; | |
1da177e4 LT |
1161 | |
1162 | retry: | |
f4fc66a8 NP |
1163 | page = __grab_cache_page(mapping, index); |
1164 | if (!page) | |
1165 | return -ENOMEM; | |
1166 | *pagep = page; | |
1167 | ||
1da177e4 | 1168 | handle = ext3_journal_start(inode, needed_blocks); |
1aa9b4b9 | 1169 | if (IS_ERR(handle)) { |
f4fc66a8 NP |
1170 | unlock_page(page); |
1171 | page_cache_release(page); | |
1aa9b4b9 AM |
1172 | ret = PTR_ERR(handle); |
1173 | goto out; | |
1174 | } | |
f4fc66a8 NP |
1175 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, |
1176 | ext3_get_block); | |
1da177e4 | 1177 | if (ret) |
f4fc66a8 | 1178 | goto write_begin_failed; |
1da177e4 LT |
1179 | |
1180 | if (ext3_should_journal_data(inode)) { | |
1181 | ret = walk_page_buffers(handle, page_buffers(page), | |
1182 | from, to, NULL, do_journal_get_write_access); | |
1183 | } | |
f4fc66a8 NP |
1184 | write_begin_failed: |
1185 | if (ret) { | |
1aa9b4b9 | 1186 | ext3_journal_stop(handle); |
f4fc66a8 NP |
1187 | unlock_page(page); |
1188 | page_cache_release(page); | |
5ec8b75e AK |
1189 | /* |
1190 | * block_write_begin may have instantiated a few blocks | |
1191 | * outside i_size. Trim these off again. Don't need | |
1192 | * i_size_read because we hold i_mutex. | |
1193 | */ | |
1194 | if (pos + len > inode->i_size) | |
1195 | vmtruncate(inode, inode->i_size); | |
f4fc66a8 | 1196 | } |
1da177e4 LT |
1197 | if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries)) |
1198 | goto retry; | |
1aa9b4b9 | 1199 | out: |
1da177e4 LT |
1200 | return ret; |
1201 | } | |
1202 | ||
f4fc66a8 | 1203 | |
d6859bfc | 1204 | int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh) |
1da177e4 LT |
1205 | { |
1206 | int err = journal_dirty_data(handle, bh); | |
1207 | if (err) | |
e05b6b52 | 1208 | ext3_journal_abort_handle(__func__, __func__, |
f4fc66a8 | 1209 | bh, handle, err); |
1da177e4 LT |
1210 | return err; |
1211 | } | |
1212 | ||
f4fc66a8 NP |
1213 | /* For write_end() in data=journal mode */ |
1214 | static int write_end_fn(handle_t *handle, struct buffer_head *bh) | |
1da177e4 LT |
1215 | { |
1216 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1217 | return 0; | |
1218 | set_buffer_uptodate(bh); | |
1219 | return ext3_journal_dirty_metadata(handle, bh); | |
1220 | } | |
1221 | ||
f4fc66a8 NP |
1222 | /* |
1223 | * Generic write_end handler for ordered and writeback ext3 journal modes. | |
1224 | * We can't use generic_write_end, because that unlocks the page and we need to | |
1225 | * unlock the page after ext3_journal_stop, but ext3_journal_stop must run | |
1226 | * after block_write_end. | |
1227 | */ | |
1228 | static int ext3_generic_write_end(struct file *file, | |
1229 | struct address_space *mapping, | |
1230 | loff_t pos, unsigned len, unsigned copied, | |
1231 | struct page *page, void *fsdata) | |
1232 | { | |
1233 | struct inode *inode = file->f_mapping->host; | |
1234 | ||
1235 | copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); | |
1236 | ||
1237 | if (pos+copied > inode->i_size) { | |
1238 | i_size_write(inode, pos+copied); | |
1239 | mark_inode_dirty(inode); | |
1240 | } | |
1241 | ||
1242 | return copied; | |
1243 | } | |
1244 | ||
1da177e4 LT |
1245 | /* |
1246 | * We need to pick up the new inode size which generic_commit_write gave us | |
1247 | * `file' can be NULL - eg, when called from page_symlink(). | |
1248 | * | |
1249 | * ext3 never places buffers on inode->i_mapping->private_list. metadata | |
1250 | * buffers are managed internally. | |
1251 | */ | |
f4fc66a8 NP |
1252 | static int ext3_ordered_write_end(struct file *file, |
1253 | struct address_space *mapping, | |
1254 | loff_t pos, unsigned len, unsigned copied, | |
1255 | struct page *page, void *fsdata) | |
1da177e4 LT |
1256 | { |
1257 | handle_t *handle = ext3_journal_current_handle(); | |
f4fc66a8 NP |
1258 | struct inode *inode = file->f_mapping->host; |
1259 | unsigned from, to; | |
1da177e4 LT |
1260 | int ret = 0, ret2; |
1261 | ||
f4fc66a8 NP |
1262 | from = pos & (PAGE_CACHE_SIZE - 1); |
1263 | to = from + len; | |
1264 | ||
1da177e4 LT |
1265 | ret = walk_page_buffers(handle, page_buffers(page), |
1266 | from, to, NULL, ext3_journal_dirty_data); | |
1267 | ||
1268 | if (ret == 0) { | |
1269 | /* | |
f4fc66a8 | 1270 | * generic_write_end() will run mark_inode_dirty() if i_size |
1da177e4 LT |
1271 | * changes. So let's piggyback the i_disksize mark_inode_dirty |
1272 | * into that. | |
1273 | */ | |
1274 | loff_t new_i_size; | |
1275 | ||
f4fc66a8 | 1276 | new_i_size = pos + copied; |
1da177e4 LT |
1277 | if (new_i_size > EXT3_I(inode)->i_disksize) |
1278 | EXT3_I(inode)->i_disksize = new_i_size; | |
7c2f3d6f | 1279 | ret2 = ext3_generic_write_end(file, mapping, pos, len, copied, |
f4fc66a8 | 1280 | page, fsdata); |
7c2f3d6f RK |
1281 | copied = ret2; |
1282 | if (ret2 < 0) | |
1283 | ret = ret2; | |
1da177e4 LT |
1284 | } |
1285 | ret2 = ext3_journal_stop(handle); | |
1286 | if (!ret) | |
1287 | ret = ret2; | |
f4fc66a8 NP |
1288 | unlock_page(page); |
1289 | page_cache_release(page); | |
1290 | ||
1291 | return ret ? ret : copied; | |
1da177e4 LT |
1292 | } |
1293 | ||
f4fc66a8 NP |
1294 | static int ext3_writeback_write_end(struct file *file, |
1295 | struct address_space *mapping, | |
1296 | loff_t pos, unsigned len, unsigned copied, | |
1297 | struct page *page, void *fsdata) | |
1da177e4 LT |
1298 | { |
1299 | handle_t *handle = ext3_journal_current_handle(); | |
f4fc66a8 | 1300 | struct inode *inode = file->f_mapping->host; |
1da177e4 LT |
1301 | int ret = 0, ret2; |
1302 | loff_t new_i_size; | |
1303 | ||
f4fc66a8 | 1304 | new_i_size = pos + copied; |
1da177e4 LT |
1305 | if (new_i_size > EXT3_I(inode)->i_disksize) |
1306 | EXT3_I(inode)->i_disksize = new_i_size; | |
1307 | ||
7c2f3d6f | 1308 | ret2 = ext3_generic_write_end(file, mapping, pos, len, copied, |
f4fc66a8 | 1309 | page, fsdata); |
7c2f3d6f RK |
1310 | copied = ret2; |
1311 | if (ret2 < 0) | |
1312 | ret = ret2; | |
1da177e4 LT |
1313 | |
1314 | ret2 = ext3_journal_stop(handle); | |
1315 | if (!ret) | |
1316 | ret = ret2; | |
f4fc66a8 NP |
1317 | unlock_page(page); |
1318 | page_cache_release(page); | |
1319 | ||
1320 | return ret ? ret : copied; | |
1da177e4 LT |
1321 | } |
1322 | ||
f4fc66a8 NP |
1323 | static int ext3_journalled_write_end(struct file *file, |
1324 | struct address_space *mapping, | |
1325 | loff_t pos, unsigned len, unsigned copied, | |
1326 | struct page *page, void *fsdata) | |
1da177e4 LT |
1327 | { |
1328 | handle_t *handle = ext3_journal_current_handle(); | |
f4fc66a8 | 1329 | struct inode *inode = mapping->host; |
1da177e4 LT |
1330 | int ret = 0, ret2; |
1331 | int partial = 0; | |
f4fc66a8 | 1332 | unsigned from, to; |
1da177e4 | 1333 | |
f4fc66a8 NP |
1334 | from = pos & (PAGE_CACHE_SIZE - 1); |
1335 | to = from + len; | |
1336 | ||
1337 | if (copied < len) { | |
1338 | if (!PageUptodate(page)) | |
1339 | copied = 0; | |
1340 | page_zero_new_buffers(page, from+copied, to); | |
1341 | } | |
1da177e4 LT |
1342 | |
1343 | ret = walk_page_buffers(handle, page_buffers(page), from, | |
f4fc66a8 | 1344 | to, &partial, write_end_fn); |
1da177e4 LT |
1345 | if (!partial) |
1346 | SetPageUptodate(page); | |
f4fc66a8 NP |
1347 | if (pos+copied > inode->i_size) |
1348 | i_size_write(inode, pos+copied); | |
1da177e4 LT |
1349 | EXT3_I(inode)->i_state |= EXT3_STATE_JDATA; |
1350 | if (inode->i_size > EXT3_I(inode)->i_disksize) { | |
1351 | EXT3_I(inode)->i_disksize = inode->i_size; | |
1352 | ret2 = ext3_mark_inode_dirty(handle, inode); | |
ae6ddcc5 | 1353 | if (!ret) |
1da177e4 LT |
1354 | ret = ret2; |
1355 | } | |
f4fc66a8 | 1356 | |
1da177e4 LT |
1357 | ret2 = ext3_journal_stop(handle); |
1358 | if (!ret) | |
1359 | ret = ret2; | |
f4fc66a8 NP |
1360 | unlock_page(page); |
1361 | page_cache_release(page); | |
1362 | ||
1363 | return ret ? ret : copied; | |
1da177e4 LT |
1364 | } |
1365 | ||
ae6ddcc5 | 1366 | /* |
1da177e4 LT |
1367 | * bmap() is special. It gets used by applications such as lilo and by |
1368 | * the swapper to find the on-disk block of a specific piece of data. | |
1369 | * | |
1370 | * Naturally, this is dangerous if the block concerned is still in the | |
1371 | * journal. If somebody makes a swapfile on an ext3 data-journaling | |
1372 | * filesystem and enables swap, then they may get a nasty shock when the | |
1373 | * data getting swapped to that swapfile suddenly gets overwritten by | |
1374 | * the original zero's written out previously to the journal and | |
ae6ddcc5 | 1375 | * awaiting writeback in the kernel's buffer cache. |
1da177e4 LT |
1376 | * |
1377 | * So, if we see any bmap calls here on a modified, data-journaled file, | |
ae6ddcc5 | 1378 | * take extra steps to flush any blocks which might be in the cache. |
1da177e4 LT |
1379 | */ |
1380 | static sector_t ext3_bmap(struct address_space *mapping, sector_t block) | |
1381 | { | |
1382 | struct inode *inode = mapping->host; | |
1383 | journal_t *journal; | |
1384 | int err; | |
1385 | ||
1386 | if (EXT3_I(inode)->i_state & EXT3_STATE_JDATA) { | |
ae6ddcc5 | 1387 | /* |
1da177e4 LT |
1388 | * This is a REALLY heavyweight approach, but the use of |
1389 | * bmap on dirty files is expected to be extremely rare: | |
1390 | * only if we run lilo or swapon on a freshly made file | |
ae6ddcc5 | 1391 | * do we expect this to happen. |
1da177e4 LT |
1392 | * |
1393 | * (bmap requires CAP_SYS_RAWIO so this does not | |
1394 | * represent an unprivileged user DOS attack --- we'd be | |
1395 | * in trouble if mortal users could trigger this path at | |
ae6ddcc5 | 1396 | * will.) |
1da177e4 LT |
1397 | * |
1398 | * NB. EXT3_STATE_JDATA is not set on files other than | |
1399 | * regular files. If somebody wants to bmap a directory | |
1400 | * or symlink and gets confused because the buffer | |
1401 | * hasn't yet been flushed to disk, they deserve | |
1402 | * everything they get. | |
1403 | */ | |
1404 | ||
1405 | EXT3_I(inode)->i_state &= ~EXT3_STATE_JDATA; | |
1406 | journal = EXT3_JOURNAL(inode); | |
1407 | journal_lock_updates(journal); | |
1408 | err = journal_flush(journal); | |
1409 | journal_unlock_updates(journal); | |
1410 | ||
1411 | if (err) | |
1412 | return 0; | |
1413 | } | |
1414 | ||
1415 | return generic_block_bmap(mapping,block,ext3_get_block); | |
1416 | } | |
1417 | ||
1418 | static int bget_one(handle_t *handle, struct buffer_head *bh) | |
1419 | { | |
1420 | get_bh(bh); | |
1421 | return 0; | |
1422 | } | |
1423 | ||
1424 | static int bput_one(handle_t *handle, struct buffer_head *bh) | |
1425 | { | |
1426 | put_bh(bh); | |
1427 | return 0; | |
1428 | } | |
1429 | ||
1430 | static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh) | |
1431 | { | |
1432 | if (buffer_mapped(bh)) | |
1433 | return ext3_journal_dirty_data(handle, bh); | |
1434 | return 0; | |
1435 | } | |
1436 | ||
1437 | /* | |
1438 | * Note that we always start a transaction even if we're not journalling | |
1439 | * data. This is to preserve ordering: any hole instantiation within | |
1440 | * __block_write_full_page -> ext3_get_block() should be journalled | |
1441 | * along with the data so we don't crash and then get metadata which | |
1442 | * refers to old data. | |
1443 | * | |
1444 | * In all journalling modes block_write_full_page() will start the I/O. | |
1445 | * | |
1446 | * Problem: | |
1447 | * | |
1448 | * ext3_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() -> | |
1449 | * ext3_writepage() | |
1450 | * | |
1451 | * Similar for: | |
1452 | * | |
1453 | * ext3_file_write() -> generic_file_write() -> __alloc_pages() -> ... | |
1454 | * | |
1455 | * Same applies to ext3_get_block(). We will deadlock on various things like | |
97461518 | 1456 | * lock_journal and i_truncate_mutex. |
1da177e4 LT |
1457 | * |
1458 | * Setting PF_MEMALLOC here doesn't work - too many internal memory | |
1459 | * allocations fail. | |
1460 | * | |
1461 | * 16May01: If we're reentered then journal_current_handle() will be | |
1462 | * non-zero. We simply *return*. | |
1463 | * | |
1464 | * 1 July 2001: @@@ FIXME: | |
1465 | * In journalled data mode, a data buffer may be metadata against the | |
1466 | * current transaction. But the same file is part of a shared mapping | |
1467 | * and someone does a writepage() on it. | |
1468 | * | |
1469 | * We will move the buffer onto the async_data list, but *after* it has | |
1470 | * been dirtied. So there's a small window where we have dirty data on | |
1471 | * BJ_Metadata. | |
1472 | * | |
1473 | * Note that this only applies to the last partial page in the file. The | |
1474 | * bit which block_write_full_page() uses prepare/commit for. (That's | |
1475 | * broken code anyway: it's wrong for msync()). | |
1476 | * | |
1477 | * It's a rare case: affects the final partial page, for journalled data | |
1478 | * where the file is subject to bith write() and writepage() in the same | |
1479 | * transction. To fix it we'll need a custom block_write_full_page(). | |
1480 | * We'll probably need that anyway for journalling writepage() output. | |
1481 | * | |
1482 | * We don't honour synchronous mounts for writepage(). That would be | |
1483 | * disastrous. Any write() or metadata operation will sync the fs for | |
1484 | * us. | |
1485 | * | |
1486 | * AKPM2: if all the page's buffers are mapped to disk and !data=journal, | |
1487 | * we don't need to open a transaction here. | |
1488 | */ | |
1489 | static int ext3_ordered_writepage(struct page *page, | |
d6859bfc | 1490 | struct writeback_control *wbc) |
1da177e4 LT |
1491 | { |
1492 | struct inode *inode = page->mapping->host; | |
1493 | struct buffer_head *page_bufs; | |
1494 | handle_t *handle = NULL; | |
1495 | int ret = 0; | |
1496 | int err; | |
1497 | ||
1498 | J_ASSERT(PageLocked(page)); | |
1499 | ||
1500 | /* | |
1501 | * We give up here if we're reentered, because it might be for a | |
1502 | * different filesystem. | |
1503 | */ | |
1504 | if (ext3_journal_current_handle()) | |
1505 | goto out_fail; | |
1506 | ||
1507 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); | |
1508 | ||
1509 | if (IS_ERR(handle)) { | |
1510 | ret = PTR_ERR(handle); | |
1511 | goto out_fail; | |
1512 | } | |
1513 | ||
1514 | if (!page_has_buffers(page)) { | |
1515 | create_empty_buffers(page, inode->i_sb->s_blocksize, | |
1516 | (1 << BH_Dirty)|(1 << BH_Uptodate)); | |
1517 | } | |
1518 | page_bufs = page_buffers(page); | |
1519 | walk_page_buffers(handle, page_bufs, 0, | |
1520 | PAGE_CACHE_SIZE, NULL, bget_one); | |
1521 | ||
1522 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1523 | ||
1524 | /* | |
1525 | * The page can become unlocked at any point now, and | |
1526 | * truncate can then come in and change things. So we | |
1527 | * can't touch *page from now on. But *page_bufs is | |
1528 | * safe due to elevated refcount. | |
1529 | */ | |
1530 | ||
1531 | /* | |
ae6ddcc5 | 1532 | * And attach them to the current transaction. But only if |
1da177e4 LT |
1533 | * block_write_full_page() succeeded. Otherwise they are unmapped, |
1534 | * and generally junk. | |
1535 | */ | |
1536 | if (ret == 0) { | |
1537 | err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE, | |
1538 | NULL, journal_dirty_data_fn); | |
1539 | if (!ret) | |
1540 | ret = err; | |
1541 | } | |
1542 | walk_page_buffers(handle, page_bufs, 0, | |
1543 | PAGE_CACHE_SIZE, NULL, bput_one); | |
1544 | err = ext3_journal_stop(handle); | |
1545 | if (!ret) | |
1546 | ret = err; | |
1547 | return ret; | |
1548 | ||
1549 | out_fail: | |
1550 | redirty_page_for_writepage(wbc, page); | |
1551 | unlock_page(page); | |
1552 | return ret; | |
1553 | } | |
1554 | ||
1da177e4 LT |
1555 | static int ext3_writeback_writepage(struct page *page, |
1556 | struct writeback_control *wbc) | |
1557 | { | |
1558 | struct inode *inode = page->mapping->host; | |
1559 | handle_t *handle = NULL; | |
1560 | int ret = 0; | |
1561 | int err; | |
1562 | ||
1563 | if (ext3_journal_current_handle()) | |
1564 | goto out_fail; | |
1565 | ||
1566 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); | |
1567 | if (IS_ERR(handle)) { | |
1568 | ret = PTR_ERR(handle); | |
1569 | goto out_fail; | |
1570 | } | |
1571 | ||
0e31f51d | 1572 | if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode)) |
1da177e4 LT |
1573 | ret = nobh_writepage(page, ext3_get_block, wbc); |
1574 | else | |
1575 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1576 | ||
1577 | err = ext3_journal_stop(handle); | |
1578 | if (!ret) | |
1579 | ret = err; | |
1580 | return ret; | |
1581 | ||
1582 | out_fail: | |
1583 | redirty_page_for_writepage(wbc, page); | |
1584 | unlock_page(page); | |
1585 | return ret; | |
1586 | } | |
1587 | ||
1588 | static int ext3_journalled_writepage(struct page *page, | |
1589 | struct writeback_control *wbc) | |
1590 | { | |
1591 | struct inode *inode = page->mapping->host; | |
1592 | handle_t *handle = NULL; | |
1593 | int ret = 0; | |
1594 | int err; | |
1595 | ||
1596 | if (ext3_journal_current_handle()) | |
1597 | goto no_write; | |
1598 | ||
1599 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); | |
1600 | if (IS_ERR(handle)) { | |
1601 | ret = PTR_ERR(handle); | |
1602 | goto no_write; | |
1603 | } | |
1604 | ||
1605 | if (!page_has_buffers(page) || PageChecked(page)) { | |
1606 | /* | |
1607 | * It's mmapped pagecache. Add buffers and journal it. There | |
1608 | * doesn't seem much point in redirtying the page here. | |
1609 | */ | |
1610 | ClearPageChecked(page); | |
1611 | ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, | |
1612 | ext3_get_block); | |
ab4eb43c DL |
1613 | if (ret != 0) { |
1614 | ext3_journal_stop(handle); | |
1da177e4 | 1615 | goto out_unlock; |
ab4eb43c | 1616 | } |
1da177e4 LT |
1617 | ret = walk_page_buffers(handle, page_buffers(page), 0, |
1618 | PAGE_CACHE_SIZE, NULL, do_journal_get_write_access); | |
1619 | ||
1620 | err = walk_page_buffers(handle, page_buffers(page), 0, | |
f4fc66a8 | 1621 | PAGE_CACHE_SIZE, NULL, write_end_fn); |
1da177e4 LT |
1622 | if (ret == 0) |
1623 | ret = err; | |
1624 | EXT3_I(inode)->i_state |= EXT3_STATE_JDATA; | |
1625 | unlock_page(page); | |
1626 | } else { | |
1627 | /* | |
1628 | * It may be a page full of checkpoint-mode buffers. We don't | |
1629 | * really know unless we go poke around in the buffer_heads. | |
1630 | * But block_write_full_page will do the right thing. | |
1631 | */ | |
1632 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1633 | } | |
1634 | err = ext3_journal_stop(handle); | |
1635 | if (!ret) | |
1636 | ret = err; | |
1637 | out: | |
1638 | return ret; | |
1639 | ||
1640 | no_write: | |
1641 | redirty_page_for_writepage(wbc, page); | |
1642 | out_unlock: | |
1643 | unlock_page(page); | |
1644 | goto out; | |
1645 | } | |
1646 | ||
1647 | static int ext3_readpage(struct file *file, struct page *page) | |
1648 | { | |
1649 | return mpage_readpage(page, ext3_get_block); | |
1650 | } | |
1651 | ||
1652 | static int | |
1653 | ext3_readpages(struct file *file, struct address_space *mapping, | |
1654 | struct list_head *pages, unsigned nr_pages) | |
1655 | { | |
1656 | return mpage_readpages(mapping, pages, nr_pages, ext3_get_block); | |
1657 | } | |
1658 | ||
2ff28e22 | 1659 | static void ext3_invalidatepage(struct page *page, unsigned long offset) |
1da177e4 LT |
1660 | { |
1661 | journal_t *journal = EXT3_JOURNAL(page->mapping->host); | |
1662 | ||
1663 | /* | |
1664 | * If it's a full truncate we just forget about the pending dirtying | |
1665 | */ | |
1666 | if (offset == 0) | |
1667 | ClearPageChecked(page); | |
1668 | ||
2ff28e22 | 1669 | journal_invalidatepage(journal, page, offset); |
1da177e4 LT |
1670 | } |
1671 | ||
27496a8c | 1672 | static int ext3_releasepage(struct page *page, gfp_t wait) |
1da177e4 LT |
1673 | { |
1674 | journal_t *journal = EXT3_JOURNAL(page->mapping->host); | |
1675 | ||
1676 | WARN_ON(PageChecked(page)); | |
1677 | if (!page_has_buffers(page)) | |
1678 | return 0; | |
1679 | return journal_try_to_free_buffers(journal, page, wait); | |
1680 | } | |
1681 | ||
1682 | /* | |
1683 | * If the O_DIRECT write will extend the file then add this inode to the | |
1684 | * orphan list. So recovery will truncate it back to the original size | |
1685 | * if the machine crashes during the write. | |
1686 | * | |
1687 | * If the O_DIRECT write is intantiating holes inside i_size and the machine | |
bd1939de JK |
1688 | * crashes then stale disk data _may_ be exposed inside the file. But current |
1689 | * VFS code falls back into buffered path in that case so we are safe. | |
1da177e4 LT |
1690 | */ |
1691 | static ssize_t ext3_direct_IO(int rw, struct kiocb *iocb, | |
1692 | const struct iovec *iov, loff_t offset, | |
1693 | unsigned long nr_segs) | |
1694 | { | |
1695 | struct file *file = iocb->ki_filp; | |
1696 | struct inode *inode = file->f_mapping->host; | |
1697 | struct ext3_inode_info *ei = EXT3_I(inode); | |
bd1939de | 1698 | handle_t *handle; |
1da177e4 LT |
1699 | ssize_t ret; |
1700 | int orphan = 0; | |
1701 | size_t count = iov_length(iov, nr_segs); | |
1702 | ||
1703 | if (rw == WRITE) { | |
1704 | loff_t final_size = offset + count; | |
1705 | ||
1da177e4 | 1706 | if (final_size > inode->i_size) { |
bd1939de JK |
1707 | /* Credits for sb + inode write */ |
1708 | handle = ext3_journal_start(inode, 2); | |
1709 | if (IS_ERR(handle)) { | |
1710 | ret = PTR_ERR(handle); | |
1711 | goto out; | |
1712 | } | |
1da177e4 | 1713 | ret = ext3_orphan_add(handle, inode); |
bd1939de JK |
1714 | if (ret) { |
1715 | ext3_journal_stop(handle); | |
1716 | goto out; | |
1717 | } | |
1da177e4 LT |
1718 | orphan = 1; |
1719 | ei->i_disksize = inode->i_size; | |
bd1939de | 1720 | ext3_journal_stop(handle); |
1da177e4 LT |
1721 | } |
1722 | } | |
1723 | ||
ae6ddcc5 | 1724 | ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, |
1da177e4 | 1725 | offset, nr_segs, |
f91a2ad2 | 1726 | ext3_get_block, NULL); |
1da177e4 | 1727 | |
bd1939de | 1728 | if (orphan) { |
1da177e4 LT |
1729 | int err; |
1730 | ||
bd1939de JK |
1731 | /* Credits for sb + inode write */ |
1732 | handle = ext3_journal_start(inode, 2); | |
1733 | if (IS_ERR(handle)) { | |
1734 | /* This is really bad luck. We've written the data | |
1735 | * but cannot extend i_size. Bail out and pretend | |
1736 | * the write failed... */ | |
1737 | ret = PTR_ERR(handle); | |
1738 | goto out; | |
1739 | } | |
1740 | if (inode->i_nlink) | |
1da177e4 | 1741 | ext3_orphan_del(handle, inode); |
bd1939de | 1742 | if (ret > 0) { |
1da177e4 LT |
1743 | loff_t end = offset + ret; |
1744 | if (end > inode->i_size) { | |
1745 | ei->i_disksize = end; | |
1746 | i_size_write(inode, end); | |
1747 | /* | |
1748 | * We're going to return a positive `ret' | |
1749 | * here due to non-zero-length I/O, so there's | |
1750 | * no way of reporting error returns from | |
1751 | * ext3_mark_inode_dirty() to userspace. So | |
1752 | * ignore it. | |
1753 | */ | |
1754 | ext3_mark_inode_dirty(handle, inode); | |
1755 | } | |
1756 | } | |
1757 | err = ext3_journal_stop(handle); | |
1758 | if (ret == 0) | |
1759 | ret = err; | |
1760 | } | |
1761 | out: | |
1762 | return ret; | |
1763 | } | |
1764 | ||
1765 | /* | |
1766 | * Pages can be marked dirty completely asynchronously from ext3's journalling | |
1767 | * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do | |
1768 | * much here because ->set_page_dirty is called under VFS locks. The page is | |
1769 | * not necessarily locked. | |
1770 | * | |
1771 | * We cannot just dirty the page and leave attached buffers clean, because the | |
1772 | * buffers' dirty state is "definitive". We cannot just set the buffers dirty | |
1773 | * or jbddirty because all the journalling code will explode. | |
1774 | * | |
1775 | * So what we do is to mark the page "pending dirty" and next time writepage | |
1776 | * is called, propagate that into the buffers appropriately. | |
1777 | */ | |
1778 | static int ext3_journalled_set_page_dirty(struct page *page) | |
1779 | { | |
1780 | SetPageChecked(page); | |
1781 | return __set_page_dirty_nobuffers(page); | |
1782 | } | |
1783 | ||
f5e54d6e | 1784 | static const struct address_space_operations ext3_ordered_aops = { |
8ab22b9a HH |
1785 | .readpage = ext3_readpage, |
1786 | .readpages = ext3_readpages, | |
1787 | .writepage = ext3_ordered_writepage, | |
1788 | .sync_page = block_sync_page, | |
1789 | .write_begin = ext3_write_begin, | |
1790 | .write_end = ext3_ordered_write_end, | |
1791 | .bmap = ext3_bmap, | |
1792 | .invalidatepage = ext3_invalidatepage, | |
1793 | .releasepage = ext3_releasepage, | |
1794 | .direct_IO = ext3_direct_IO, | |
1795 | .migratepage = buffer_migrate_page, | |
1796 | .is_partially_uptodate = block_is_partially_uptodate, | |
1da177e4 LT |
1797 | }; |
1798 | ||
f5e54d6e | 1799 | static const struct address_space_operations ext3_writeback_aops = { |
8ab22b9a HH |
1800 | .readpage = ext3_readpage, |
1801 | .readpages = ext3_readpages, | |
1802 | .writepage = ext3_writeback_writepage, | |
1803 | .sync_page = block_sync_page, | |
1804 | .write_begin = ext3_write_begin, | |
1805 | .write_end = ext3_writeback_write_end, | |
1806 | .bmap = ext3_bmap, | |
1807 | .invalidatepage = ext3_invalidatepage, | |
1808 | .releasepage = ext3_releasepage, | |
1809 | .direct_IO = ext3_direct_IO, | |
1810 | .migratepage = buffer_migrate_page, | |
1811 | .is_partially_uptodate = block_is_partially_uptodate, | |
1da177e4 LT |
1812 | }; |
1813 | ||
f5e54d6e | 1814 | static const struct address_space_operations ext3_journalled_aops = { |
8ab22b9a HH |
1815 | .readpage = ext3_readpage, |
1816 | .readpages = ext3_readpages, | |
1817 | .writepage = ext3_journalled_writepage, | |
1818 | .sync_page = block_sync_page, | |
1819 | .write_begin = ext3_write_begin, | |
1820 | .write_end = ext3_journalled_write_end, | |
1821 | .set_page_dirty = ext3_journalled_set_page_dirty, | |
1822 | .bmap = ext3_bmap, | |
1823 | .invalidatepage = ext3_invalidatepage, | |
1824 | .releasepage = ext3_releasepage, | |
1825 | .is_partially_uptodate = block_is_partially_uptodate, | |
1da177e4 LT |
1826 | }; |
1827 | ||
1828 | void ext3_set_aops(struct inode *inode) | |
1829 | { | |
1830 | if (ext3_should_order_data(inode)) | |
1831 | inode->i_mapping->a_ops = &ext3_ordered_aops; | |
1832 | else if (ext3_should_writeback_data(inode)) | |
1833 | inode->i_mapping->a_ops = &ext3_writeback_aops; | |
1834 | else | |
1835 | inode->i_mapping->a_ops = &ext3_journalled_aops; | |
1836 | } | |
1837 | ||
1838 | /* | |
1839 | * ext3_block_truncate_page() zeroes out a mapping from file offset `from' | |
1840 | * up to the end of the block which corresponds to `from'. | |
1841 | * This required during truncate. We need to physically zero the tail end | |
1842 | * of that block so it doesn't yield old data if the file is later grown. | |
1843 | */ | |
1844 | static int ext3_block_truncate_page(handle_t *handle, struct page *page, | |
1845 | struct address_space *mapping, loff_t from) | |
1846 | { | |
43d23f90 | 1847 | ext3_fsblk_t index = from >> PAGE_CACHE_SHIFT; |
1da177e4 LT |
1848 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
1849 | unsigned blocksize, iblock, length, pos; | |
1850 | struct inode *inode = mapping->host; | |
1851 | struct buffer_head *bh; | |
1852 | int err = 0; | |
1da177e4 LT |
1853 | |
1854 | blocksize = inode->i_sb->s_blocksize; | |
1855 | length = blocksize - (offset & (blocksize - 1)); | |
1856 | iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
1857 | ||
1858 | /* | |
1859 | * For "nobh" option, we can only work if we don't need to | |
1860 | * read-in the page - otherwise we create buffers to do the IO. | |
1861 | */ | |
cd6ef84e BP |
1862 | if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && |
1863 | ext3_should_writeback_data(inode) && PageUptodate(page)) { | |
eebd2aa3 | 1864 | zero_user(page, offset, length); |
cd6ef84e BP |
1865 | set_page_dirty(page); |
1866 | goto unlock; | |
1da177e4 LT |
1867 | } |
1868 | ||
1869 | if (!page_has_buffers(page)) | |
1870 | create_empty_buffers(page, blocksize, 0); | |
1871 | ||
1872 | /* Find the buffer that contains "offset" */ | |
1873 | bh = page_buffers(page); | |
1874 | pos = blocksize; | |
1875 | while (offset >= pos) { | |
1876 | bh = bh->b_this_page; | |
1877 | iblock++; | |
1878 | pos += blocksize; | |
1879 | } | |
1880 | ||
1881 | err = 0; | |
1882 | if (buffer_freed(bh)) { | |
1883 | BUFFER_TRACE(bh, "freed: skip"); | |
1884 | goto unlock; | |
1885 | } | |
1886 | ||
1887 | if (!buffer_mapped(bh)) { | |
1888 | BUFFER_TRACE(bh, "unmapped"); | |
1889 | ext3_get_block(inode, iblock, bh, 0); | |
1890 | /* unmapped? It's a hole - nothing to do */ | |
1891 | if (!buffer_mapped(bh)) { | |
1892 | BUFFER_TRACE(bh, "still unmapped"); | |
1893 | goto unlock; | |
1894 | } | |
1895 | } | |
1896 | ||
1897 | /* Ok, it's mapped. Make sure it's up-to-date */ | |
1898 | if (PageUptodate(page)) | |
1899 | set_buffer_uptodate(bh); | |
1900 | ||
1901 | if (!buffer_uptodate(bh)) { | |
1902 | err = -EIO; | |
1903 | ll_rw_block(READ, 1, &bh); | |
1904 | wait_on_buffer(bh); | |
1905 | /* Uhhuh. Read error. Complain and punt. */ | |
1906 | if (!buffer_uptodate(bh)) | |
1907 | goto unlock; | |
1908 | } | |
1909 | ||
1910 | if (ext3_should_journal_data(inode)) { | |
1911 | BUFFER_TRACE(bh, "get write access"); | |
1912 | err = ext3_journal_get_write_access(handle, bh); | |
1913 | if (err) | |
1914 | goto unlock; | |
1915 | } | |
1916 | ||
eebd2aa3 | 1917 | zero_user(page, offset, length); |
1da177e4 LT |
1918 | BUFFER_TRACE(bh, "zeroed end of block"); |
1919 | ||
1920 | err = 0; | |
1921 | if (ext3_should_journal_data(inode)) { | |
1922 | err = ext3_journal_dirty_metadata(handle, bh); | |
1923 | } else { | |
1924 | if (ext3_should_order_data(inode)) | |
1925 | err = ext3_journal_dirty_data(handle, bh); | |
1926 | mark_buffer_dirty(bh); | |
1927 | } | |
1928 | ||
1929 | unlock: | |
1930 | unlock_page(page); | |
1931 | page_cache_release(page); | |
1932 | return err; | |
1933 | } | |
1934 | ||
1935 | /* | |
1936 | * Probably it should be a library function... search for first non-zero word | |
1937 | * or memcmp with zero_page, whatever is better for particular architecture. | |
1938 | * Linus? | |
1939 | */ | |
1940 | static inline int all_zeroes(__le32 *p, __le32 *q) | |
1941 | { | |
1942 | while (p < q) | |
1943 | if (*p++) | |
1944 | return 0; | |
1945 | return 1; | |
1946 | } | |
1947 | ||
1948 | /** | |
1949 | * ext3_find_shared - find the indirect blocks for partial truncation. | |
1950 | * @inode: inode in question | |
1951 | * @depth: depth of the affected branch | |
1952 | * @offsets: offsets of pointers in that branch (see ext3_block_to_path) | |
1953 | * @chain: place to store the pointers to partial indirect blocks | |
1954 | * @top: place to the (detached) top of branch | |
1955 | * | |
1956 | * This is a helper function used by ext3_truncate(). | |
1957 | * | |
1958 | * When we do truncate() we may have to clean the ends of several | |
1959 | * indirect blocks but leave the blocks themselves alive. Block is | |
1960 | * partially truncated if some data below the new i_size is refered | |
1961 | * from it (and it is on the path to the first completely truncated | |
1962 | * data block, indeed). We have to free the top of that path along | |
1963 | * with everything to the right of the path. Since no allocation | |
1964 | * past the truncation point is possible until ext3_truncate() | |
1965 | * finishes, we may safely do the latter, but top of branch may | |
1966 | * require special attention - pageout below the truncation point | |
1967 | * might try to populate it. | |
1968 | * | |
1969 | * We atomically detach the top of branch from the tree, store the | |
1970 | * block number of its root in *@top, pointers to buffer_heads of | |
1971 | * partially truncated blocks - in @chain[].bh and pointers to | |
1972 | * their last elements that should not be removed - in | |
1973 | * @chain[].p. Return value is the pointer to last filled element | |
1974 | * of @chain. | |
1975 | * | |
1976 | * The work left to caller to do the actual freeing of subtrees: | |
1977 | * a) free the subtree starting from *@top | |
1978 | * b) free the subtrees whose roots are stored in | |
1979 | * (@chain[i].p+1 .. end of @chain[i].bh->b_data) | |
1980 | * c) free the subtrees growing from the inode past the @chain[0]. | |
1981 | * (no partially truncated stuff there). */ | |
1982 | ||
d6859bfc AM |
1983 | static Indirect *ext3_find_shared(struct inode *inode, int depth, |
1984 | int offsets[4], Indirect chain[4], __le32 *top) | |
1da177e4 LT |
1985 | { |
1986 | Indirect *partial, *p; | |
1987 | int k, err; | |
1988 | ||
1989 | *top = 0; | |
1990 | /* Make k index the deepest non-null offest + 1 */ | |
1991 | for (k = depth; k > 1 && !offsets[k-1]; k--) | |
1992 | ; | |
1993 | partial = ext3_get_branch(inode, k, offsets, chain, &err); | |
1994 | /* Writer: pointers */ | |
1995 | if (!partial) | |
1996 | partial = chain + k-1; | |
1997 | /* | |
1998 | * If the branch acquired continuation since we've looked at it - | |
1999 | * fine, it should all survive and (new) top doesn't belong to us. | |
2000 | */ | |
2001 | if (!partial->key && *partial->p) | |
2002 | /* Writer: end */ | |
2003 | goto no_top; | |
2004 | for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--) | |
2005 | ; | |
2006 | /* | |
2007 | * OK, we've found the last block that must survive. The rest of our | |
2008 | * branch should be detached before unlocking. However, if that rest | |
2009 | * of branch is all ours and does not grow immediately from the inode | |
2010 | * it's easier to cheat and just decrement partial->p. | |
2011 | */ | |
2012 | if (p == chain + k - 1 && p > chain) { | |
2013 | p->p--; | |
2014 | } else { | |
2015 | *top = *p->p; | |
2016 | /* Nope, don't do this in ext3. Must leave the tree intact */ | |
2017 | #if 0 | |
2018 | *p->p = 0; | |
2019 | #endif | |
2020 | } | |
2021 | /* Writer: end */ | |
2022 | ||
d6859bfc | 2023 | while(partial > p) { |
1da177e4 LT |
2024 | brelse(partial->bh); |
2025 | partial--; | |
2026 | } | |
2027 | no_top: | |
2028 | return partial; | |
2029 | } | |
2030 | ||
2031 | /* | |
2032 | * Zero a number of block pointers in either an inode or an indirect block. | |
2033 | * If we restart the transaction we must again get write access to the | |
2034 | * indirect block for further modification. | |
2035 | * | |
2036 | * We release `count' blocks on disk, but (last - first) may be greater | |
2037 | * than `count' because there can be holes in there. | |
2038 | */ | |
d6859bfc | 2039 | static void ext3_clear_blocks(handle_t *handle, struct inode *inode, |
43d23f90 | 2040 | struct buffer_head *bh, ext3_fsblk_t block_to_free, |
d6859bfc | 2041 | unsigned long count, __le32 *first, __le32 *last) |
1da177e4 LT |
2042 | { |
2043 | __le32 *p; | |
2044 | if (try_to_extend_transaction(handle, inode)) { | |
2045 | if (bh) { | |
2046 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
2047 | ext3_journal_dirty_metadata(handle, bh); | |
2048 | } | |
2049 | ext3_mark_inode_dirty(handle, inode); | |
2050 | ext3_journal_test_restart(handle, inode); | |
2051 | if (bh) { | |
2052 | BUFFER_TRACE(bh, "retaking write access"); | |
2053 | ext3_journal_get_write_access(handle, bh); | |
2054 | } | |
2055 | } | |
2056 | ||
2057 | /* | |
2058 | * Any buffers which are on the journal will be in memory. We find | |
2059 | * them on the hash table so journal_revoke() will run journal_forget() | |
2060 | * on them. We've already detached each block from the file, so | |
2061 | * bforget() in journal_forget() should be safe. | |
2062 | * | |
2063 | * AKPM: turn on bforget in journal_forget()!!! | |
2064 | */ | |
2065 | for (p = first; p < last; p++) { | |
2066 | u32 nr = le32_to_cpu(*p); | |
2067 | if (nr) { | |
2068 | struct buffer_head *bh; | |
2069 | ||
2070 | *p = 0; | |
2071 | bh = sb_find_get_block(inode->i_sb, nr); | |
2072 | ext3_forget(handle, 0, inode, bh, nr); | |
2073 | } | |
2074 | } | |
2075 | ||
2076 | ext3_free_blocks(handle, inode, block_to_free, count); | |
2077 | } | |
2078 | ||
2079 | /** | |
2080 | * ext3_free_data - free a list of data blocks | |
2081 | * @handle: handle for this transaction | |
2082 | * @inode: inode we are dealing with | |
2083 | * @this_bh: indirect buffer_head which contains *@first and *@last | |
2084 | * @first: array of block numbers | |
2085 | * @last: points immediately past the end of array | |
2086 | * | |
2087 | * We are freeing all blocks refered from that array (numbers are stored as | |
2088 | * little-endian 32-bit) and updating @inode->i_blocks appropriately. | |
2089 | * | |
2090 | * We accumulate contiguous runs of blocks to free. Conveniently, if these | |
2091 | * blocks are contiguous then releasing them at one time will only affect one | |
2092 | * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't | |
2093 | * actually use a lot of journal space. | |
2094 | * | |
2095 | * @this_bh will be %NULL if @first and @last point into the inode's direct | |
2096 | * block pointers. | |
2097 | */ | |
2098 | static void ext3_free_data(handle_t *handle, struct inode *inode, | |
2099 | struct buffer_head *this_bh, | |
2100 | __le32 *first, __le32 *last) | |
2101 | { | |
43d23f90 | 2102 | ext3_fsblk_t block_to_free = 0; /* Starting block # of a run */ |
ae6ddcc5 | 2103 | unsigned long count = 0; /* Number of blocks in the run */ |
1da177e4 LT |
2104 | __le32 *block_to_free_p = NULL; /* Pointer into inode/ind |
2105 | corresponding to | |
2106 | block_to_free */ | |
43d23f90 | 2107 | ext3_fsblk_t nr; /* Current block # */ |
1da177e4 LT |
2108 | __le32 *p; /* Pointer into inode/ind |
2109 | for current block */ | |
2110 | int err; | |
2111 | ||
2112 | if (this_bh) { /* For indirect block */ | |
2113 | BUFFER_TRACE(this_bh, "get_write_access"); | |
2114 | err = ext3_journal_get_write_access(handle, this_bh); | |
2115 | /* Important: if we can't update the indirect pointers | |
2116 | * to the blocks, we can't free them. */ | |
2117 | if (err) | |
2118 | return; | |
2119 | } | |
2120 | ||
2121 | for (p = first; p < last; p++) { | |
2122 | nr = le32_to_cpu(*p); | |
2123 | if (nr) { | |
2124 | /* accumulate blocks to free if they're contiguous */ | |
2125 | if (count == 0) { | |
2126 | block_to_free = nr; | |
2127 | block_to_free_p = p; | |
2128 | count = 1; | |
2129 | } else if (nr == block_to_free + count) { | |
2130 | count++; | |
2131 | } else { | |
ae6ddcc5 | 2132 | ext3_clear_blocks(handle, inode, this_bh, |
1da177e4 LT |
2133 | block_to_free, |
2134 | count, block_to_free_p, p); | |
2135 | block_to_free = nr; | |
2136 | block_to_free_p = p; | |
2137 | count = 1; | |
2138 | } | |
2139 | } | |
2140 | } | |
2141 | ||
2142 | if (count > 0) | |
2143 | ext3_clear_blocks(handle, inode, this_bh, block_to_free, | |
2144 | count, block_to_free_p, p); | |
2145 | ||
2146 | if (this_bh) { | |
2147 | BUFFER_TRACE(this_bh, "call ext3_journal_dirty_metadata"); | |
3ccc3167 DG |
2148 | |
2149 | /* | |
2150 | * The buffer head should have an attached journal head at this | |
2151 | * point. However, if the data is corrupted and an indirect | |
2152 | * block pointed to itself, it would have been detached when | |
2153 | * the block was cleared. Check for this instead of OOPSing. | |
2154 | */ | |
2155 | if (bh2jh(this_bh)) | |
2156 | ext3_journal_dirty_metadata(handle, this_bh); | |
2157 | else | |
2158 | ext3_error(inode->i_sb, "ext3_free_data", | |
2159 | "circular indirect block detected, " | |
2160 | "inode=%lu, block=%llu", | |
2161 | inode->i_ino, | |
2162 | (unsigned long long)this_bh->b_blocknr); | |
1da177e4 LT |
2163 | } |
2164 | } | |
2165 | ||
2166 | /** | |
2167 | * ext3_free_branches - free an array of branches | |
2168 | * @handle: JBD handle for this transaction | |
2169 | * @inode: inode we are dealing with | |
2170 | * @parent_bh: the buffer_head which contains *@first and *@last | |
2171 | * @first: array of block numbers | |
2172 | * @last: pointer immediately past the end of array | |
2173 | * @depth: depth of the branches to free | |
2174 | * | |
2175 | * We are freeing all blocks refered from these branches (numbers are | |
2176 | * stored as little-endian 32-bit) and updating @inode->i_blocks | |
2177 | * appropriately. | |
2178 | */ | |
2179 | static void ext3_free_branches(handle_t *handle, struct inode *inode, | |
2180 | struct buffer_head *parent_bh, | |
2181 | __le32 *first, __le32 *last, int depth) | |
2182 | { | |
43d23f90 | 2183 | ext3_fsblk_t nr; |
1da177e4 LT |
2184 | __le32 *p; |
2185 | ||
2186 | if (is_handle_aborted(handle)) | |
2187 | return; | |
2188 | ||
2189 | if (depth--) { | |
2190 | struct buffer_head *bh; | |
2191 | int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
2192 | p = last; | |
2193 | while (--p >= first) { | |
2194 | nr = le32_to_cpu(*p); | |
2195 | if (!nr) | |
2196 | continue; /* A hole */ | |
2197 | ||
2198 | /* Go read the buffer for the next level down */ | |
2199 | bh = sb_bread(inode->i_sb, nr); | |
2200 | ||
2201 | /* | |
2202 | * A read failure? Report error and clear slot | |
2203 | * (should be rare). | |
2204 | */ | |
2205 | if (!bh) { | |
2206 | ext3_error(inode->i_sb, "ext3_free_branches", | |
eee194e7 | 2207 | "Read failure, inode=%lu, block="E3FSBLK, |
1da177e4 LT |
2208 | inode->i_ino, nr); |
2209 | continue; | |
2210 | } | |
2211 | ||
2212 | /* This zaps the entire block. Bottom up. */ | |
2213 | BUFFER_TRACE(bh, "free child branches"); | |
2214 | ext3_free_branches(handle, inode, bh, | |
2215 | (__le32*)bh->b_data, | |
2216 | (__le32*)bh->b_data + addr_per_block, | |
2217 | depth); | |
2218 | ||
2219 | /* | |
2220 | * We've probably journalled the indirect block several | |
2221 | * times during the truncate. But it's no longer | |
2222 | * needed and we now drop it from the transaction via | |
2223 | * journal_revoke(). | |
2224 | * | |
2225 | * That's easy if it's exclusively part of this | |
2226 | * transaction. But if it's part of the committing | |
2227 | * transaction then journal_forget() will simply | |
2228 | * brelse() it. That means that if the underlying | |
2229 | * block is reallocated in ext3_get_block(), | |
2230 | * unmap_underlying_metadata() will find this block | |
2231 | * and will try to get rid of it. damn, damn. | |
2232 | * | |
2233 | * If this block has already been committed to the | |
2234 | * journal, a revoke record will be written. And | |
2235 | * revoke records must be emitted *before* clearing | |
2236 | * this block's bit in the bitmaps. | |
2237 | */ | |
2238 | ext3_forget(handle, 1, inode, bh, bh->b_blocknr); | |
2239 | ||
2240 | /* | |
2241 | * Everything below this this pointer has been | |
2242 | * released. Now let this top-of-subtree go. | |
2243 | * | |
2244 | * We want the freeing of this indirect block to be | |
2245 | * atomic in the journal with the updating of the | |
2246 | * bitmap block which owns it. So make some room in | |
2247 | * the journal. | |
2248 | * | |
2249 | * We zero the parent pointer *after* freeing its | |
2250 | * pointee in the bitmaps, so if extend_transaction() | |
2251 | * for some reason fails to put the bitmap changes and | |
2252 | * the release into the same transaction, recovery | |
2253 | * will merely complain about releasing a free block, | |
2254 | * rather than leaking blocks. | |
2255 | */ | |
2256 | if (is_handle_aborted(handle)) | |
2257 | return; | |
2258 | if (try_to_extend_transaction(handle, inode)) { | |
2259 | ext3_mark_inode_dirty(handle, inode); | |
2260 | ext3_journal_test_restart(handle, inode); | |
2261 | } | |
2262 | ||
2263 | ext3_free_blocks(handle, inode, nr, 1); | |
2264 | ||
2265 | if (parent_bh) { | |
2266 | /* | |
2267 | * The block which we have just freed is | |
2268 | * pointed to by an indirect block: journal it | |
2269 | */ | |
2270 | BUFFER_TRACE(parent_bh, "get_write_access"); | |
2271 | if (!ext3_journal_get_write_access(handle, | |
2272 | parent_bh)){ | |
2273 | *p = 0; | |
2274 | BUFFER_TRACE(parent_bh, | |
2275 | "call ext3_journal_dirty_metadata"); | |
ae6ddcc5 | 2276 | ext3_journal_dirty_metadata(handle, |
1da177e4 LT |
2277 | parent_bh); |
2278 | } | |
2279 | } | |
2280 | } | |
2281 | } else { | |
2282 | /* We have reached the bottom of the tree. */ | |
2283 | BUFFER_TRACE(parent_bh, "free data blocks"); | |
2284 | ext3_free_data(handle, inode, parent_bh, first, last); | |
2285 | } | |
2286 | } | |
2287 | ||
ae76dd9a DG |
2288 | int ext3_can_truncate(struct inode *inode) |
2289 | { | |
2290 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | |
2291 | return 0; | |
2292 | if (S_ISREG(inode->i_mode)) | |
2293 | return 1; | |
2294 | if (S_ISDIR(inode->i_mode)) | |
2295 | return 1; | |
2296 | if (S_ISLNK(inode->i_mode)) | |
2297 | return !ext3_inode_is_fast_symlink(inode); | |
2298 | return 0; | |
2299 | } | |
2300 | ||
1da177e4 LT |
2301 | /* |
2302 | * ext3_truncate() | |
2303 | * | |
2304 | * We block out ext3_get_block() block instantiations across the entire | |
2305 | * transaction, and VFS/VM ensures that ext3_truncate() cannot run | |
2306 | * simultaneously on behalf of the same inode. | |
2307 | * | |
2308 | * As we work through the truncate and commmit bits of it to the journal there | |
2309 | * is one core, guiding principle: the file's tree must always be consistent on | |
2310 | * disk. We must be able to restart the truncate after a crash. | |
2311 | * | |
2312 | * The file's tree may be transiently inconsistent in memory (although it | |
2313 | * probably isn't), but whenever we close off and commit a journal transaction, | |
2314 | * the contents of (the filesystem + the journal) must be consistent and | |
2315 | * restartable. It's pretty simple, really: bottom up, right to left (although | |
2316 | * left-to-right works OK too). | |
2317 | * | |
2318 | * Note that at recovery time, journal replay occurs *before* the restart of | |
2319 | * truncate against the orphan inode list. | |
2320 | * | |
2321 | * The committed inode has the new, desired i_size (which is the same as | |
2322 | * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see | |
2323 | * that this inode's truncate did not complete and it will again call | |
2324 | * ext3_truncate() to have another go. So there will be instantiated blocks | |
2325 | * to the right of the truncation point in a crashed ext3 filesystem. But | |
2326 | * that's fine - as long as they are linked from the inode, the post-crash | |
2327 | * ext3_truncate() run will find them and release them. | |
2328 | */ | |
d6859bfc | 2329 | void ext3_truncate(struct inode *inode) |
1da177e4 LT |
2330 | { |
2331 | handle_t *handle; | |
2332 | struct ext3_inode_info *ei = EXT3_I(inode); | |
2333 | __le32 *i_data = ei->i_data; | |
2334 | int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
2335 | struct address_space *mapping = inode->i_mapping; | |
2336 | int offsets[4]; | |
2337 | Indirect chain[4]; | |
2338 | Indirect *partial; | |
2339 | __le32 nr = 0; | |
2340 | int n; | |
2341 | long last_block; | |
2342 | unsigned blocksize = inode->i_sb->s_blocksize; | |
2343 | struct page *page; | |
2344 | ||
ae76dd9a | 2345 | if (!ext3_can_truncate(inode)) |
1da177e4 LT |
2346 | return; |
2347 | ||
2348 | /* | |
2349 | * We have to lock the EOF page here, because lock_page() nests | |
2350 | * outside journal_start(). | |
2351 | */ | |
2352 | if ((inode->i_size & (blocksize - 1)) == 0) { | |
2353 | /* Block boundary? Nothing to do */ | |
2354 | page = NULL; | |
2355 | } else { | |
2356 | page = grab_cache_page(mapping, | |
2357 | inode->i_size >> PAGE_CACHE_SHIFT); | |
2358 | if (!page) | |
2359 | return; | |
2360 | } | |
2361 | ||
2362 | handle = start_transaction(inode); | |
2363 | if (IS_ERR(handle)) { | |
2364 | if (page) { | |
2365 | clear_highpage(page); | |
2366 | flush_dcache_page(page); | |
2367 | unlock_page(page); | |
2368 | page_cache_release(page); | |
2369 | } | |
2370 | return; /* AKPM: return what? */ | |
2371 | } | |
2372 | ||
2373 | last_block = (inode->i_size + blocksize-1) | |
2374 | >> EXT3_BLOCK_SIZE_BITS(inode->i_sb); | |
2375 | ||
2376 | if (page) | |
2377 | ext3_block_truncate_page(handle, page, mapping, inode->i_size); | |
2378 | ||
2379 | n = ext3_block_to_path(inode, last_block, offsets, NULL); | |
2380 | if (n == 0) | |
2381 | goto out_stop; /* error */ | |
2382 | ||
2383 | /* | |
2384 | * OK. This truncate is going to happen. We add the inode to the | |
2385 | * orphan list, so that if this truncate spans multiple transactions, | |
2386 | * and we crash, we will resume the truncate when the filesystem | |
2387 | * recovers. It also marks the inode dirty, to catch the new size. | |
2388 | * | |
2389 | * Implication: the file must always be in a sane, consistent | |
2390 | * truncatable state while each transaction commits. | |
2391 | */ | |
2392 | if (ext3_orphan_add(handle, inode)) | |
2393 | goto out_stop; | |
2394 | ||
2395 | /* | |
2396 | * The orphan list entry will now protect us from any crash which | |
2397 | * occurs before the truncate completes, so it is now safe to propagate | |
2398 | * the new, shorter inode size (held for now in i_size) into the | |
2399 | * on-disk inode. We do this via i_disksize, which is the value which | |
2400 | * ext3 *really* writes onto the disk inode. | |
2401 | */ | |
2402 | ei->i_disksize = inode->i_size; | |
2403 | ||
2404 | /* | |
2405 | * From here we block out all ext3_get_block() callers who want to | |
2406 | * modify the block allocation tree. | |
2407 | */ | |
97461518 | 2408 | mutex_lock(&ei->truncate_mutex); |
1da177e4 LT |
2409 | |
2410 | if (n == 1) { /* direct blocks */ | |
2411 | ext3_free_data(handle, inode, NULL, i_data+offsets[0], | |
2412 | i_data + EXT3_NDIR_BLOCKS); | |
2413 | goto do_indirects; | |
2414 | } | |
2415 | ||
2416 | partial = ext3_find_shared(inode, n, offsets, chain, &nr); | |
2417 | /* Kill the top of shared branch (not detached) */ | |
2418 | if (nr) { | |
2419 | if (partial == chain) { | |
2420 | /* Shared branch grows from the inode */ | |
2421 | ext3_free_branches(handle, inode, NULL, | |
2422 | &nr, &nr+1, (chain+n-1) - partial); | |
2423 | *partial->p = 0; | |
2424 | /* | |
2425 | * We mark the inode dirty prior to restart, | |
2426 | * and prior to stop. No need for it here. | |
2427 | */ | |
2428 | } else { | |
2429 | /* Shared branch grows from an indirect block */ | |
2430 | BUFFER_TRACE(partial->bh, "get_write_access"); | |
2431 | ext3_free_branches(handle, inode, partial->bh, | |
2432 | partial->p, | |
2433 | partial->p+1, (chain+n-1) - partial); | |
2434 | } | |
2435 | } | |
2436 | /* Clear the ends of indirect blocks on the shared branch */ | |
2437 | while (partial > chain) { | |
2438 | ext3_free_branches(handle, inode, partial->bh, partial->p + 1, | |
2439 | (__le32*)partial->bh->b_data+addr_per_block, | |
2440 | (chain+n-1) - partial); | |
2441 | BUFFER_TRACE(partial->bh, "call brelse"); | |
2442 | brelse (partial->bh); | |
2443 | partial--; | |
2444 | } | |
2445 | do_indirects: | |
2446 | /* Kill the remaining (whole) subtrees */ | |
2447 | switch (offsets[0]) { | |
d6859bfc AM |
2448 | default: |
2449 | nr = i_data[EXT3_IND_BLOCK]; | |
2450 | if (nr) { | |
2451 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 1); | |
2452 | i_data[EXT3_IND_BLOCK] = 0; | |
2453 | } | |
2454 | case EXT3_IND_BLOCK: | |
2455 | nr = i_data[EXT3_DIND_BLOCK]; | |
2456 | if (nr) { | |
2457 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 2); | |
2458 | i_data[EXT3_DIND_BLOCK] = 0; | |
2459 | } | |
2460 | case EXT3_DIND_BLOCK: | |
2461 | nr = i_data[EXT3_TIND_BLOCK]; | |
2462 | if (nr) { | |
2463 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 3); | |
2464 | i_data[EXT3_TIND_BLOCK] = 0; | |
2465 | } | |
2466 | case EXT3_TIND_BLOCK: | |
2467 | ; | |
1da177e4 LT |
2468 | } |
2469 | ||
2470 | ext3_discard_reservation(inode); | |
2471 | ||
97461518 | 2472 | mutex_unlock(&ei->truncate_mutex); |
1da177e4 LT |
2473 | inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; |
2474 | ext3_mark_inode_dirty(handle, inode); | |
2475 | ||
d6859bfc AM |
2476 | /* |
2477 | * In a multi-transaction truncate, we only make the final transaction | |
2478 | * synchronous | |
2479 | */ | |
1da177e4 LT |
2480 | if (IS_SYNC(inode)) |
2481 | handle->h_sync = 1; | |
2482 | out_stop: | |
2483 | /* | |
2484 | * If this was a simple ftruncate(), and the file will remain alive | |
2485 | * then we need to clear up the orphan record which we created above. | |
2486 | * However, if this was a real unlink then we were called by | |
2487 | * ext3_delete_inode(), and we allow that function to clean up the | |
2488 | * orphan info for us. | |
2489 | */ | |
2490 | if (inode->i_nlink) | |
2491 | ext3_orphan_del(handle, inode); | |
2492 | ||
2493 | ext3_journal_stop(handle); | |
2494 | } | |
2495 | ||
43d23f90 | 2496 | static ext3_fsblk_t ext3_get_inode_block(struct super_block *sb, |
1da177e4 LT |
2497 | unsigned long ino, struct ext3_iloc *iloc) |
2498 | { | |
e0e369a7 | 2499 | unsigned long block_group; |
43d23f90 MC |
2500 | unsigned long offset; |
2501 | ext3_fsblk_t block; | |
e0e369a7 | 2502 | struct ext3_group_desc *gdp; |
1da177e4 | 2503 | |
2ccb48eb NB |
2504 | if (!ext3_valid_inum(sb, ino)) { |
2505 | /* | |
2506 | * This error is already checked for in namei.c unless we are | |
2507 | * looking at an NFS filehandle, in which case no error | |
2508 | * report is needed | |
2509 | */ | |
1da177e4 LT |
2510 | return 0; |
2511 | } | |
2ccb48eb | 2512 | |
1da177e4 | 2513 | block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb); |
e0e369a7 AM |
2514 | gdp = ext3_get_group_desc(sb, block_group, NULL); |
2515 | if (!gdp) | |
1da177e4 | 2516 | return 0; |
1da177e4 LT |
2517 | /* |
2518 | * Figure out the offset within the block group inode table | |
2519 | */ | |
2520 | offset = ((ino - 1) % EXT3_INODES_PER_GROUP(sb)) * | |
2521 | EXT3_INODE_SIZE(sb); | |
e0e369a7 | 2522 | block = le32_to_cpu(gdp->bg_inode_table) + |
1da177e4 LT |
2523 | (offset >> EXT3_BLOCK_SIZE_BITS(sb)); |
2524 | ||
2525 | iloc->block_group = block_group; | |
2526 | iloc->offset = offset & (EXT3_BLOCK_SIZE(sb) - 1); | |
2527 | return block; | |
2528 | } | |
2529 | ||
2530 | /* | |
2531 | * ext3_get_inode_loc returns with an extra refcount against the inode's | |
2532 | * underlying buffer_head on success. If 'in_mem' is true, we have all | |
2533 | * data in memory that is needed to recreate the on-disk version of this | |
2534 | * inode. | |
2535 | */ | |
2536 | static int __ext3_get_inode_loc(struct inode *inode, | |
2537 | struct ext3_iloc *iloc, int in_mem) | |
2538 | { | |
43d23f90 | 2539 | ext3_fsblk_t block; |
1da177e4 LT |
2540 | struct buffer_head *bh; |
2541 | ||
2542 | block = ext3_get_inode_block(inode->i_sb, inode->i_ino, iloc); | |
2543 | if (!block) | |
2544 | return -EIO; | |
2545 | ||
2546 | bh = sb_getblk(inode->i_sb, block); | |
2547 | if (!bh) { | |
2548 | ext3_error (inode->i_sb, "ext3_get_inode_loc", | |
2549 | "unable to read inode block - " | |
43d23f90 MC |
2550 | "inode=%lu, block="E3FSBLK, |
2551 | inode->i_ino, block); | |
1da177e4 LT |
2552 | return -EIO; |
2553 | } | |
2554 | if (!buffer_uptodate(bh)) { | |
2555 | lock_buffer(bh); | |
95450f5a HK |
2556 | |
2557 | /* | |
2558 | * If the buffer has the write error flag, we have failed | |
2559 | * to write out another inode in the same block. In this | |
2560 | * case, we don't have to read the block because we may | |
2561 | * read the old inode data successfully. | |
2562 | */ | |
2563 | if (buffer_write_io_error(bh) && !buffer_uptodate(bh)) | |
2564 | set_buffer_uptodate(bh); | |
2565 | ||
1da177e4 LT |
2566 | if (buffer_uptodate(bh)) { |
2567 | /* someone brought it uptodate while we waited */ | |
2568 | unlock_buffer(bh); | |
2569 | goto has_buffer; | |
2570 | } | |
2571 | ||
2572 | /* | |
2573 | * If we have all information of the inode in memory and this | |
2574 | * is the only valid inode in the block, we need not read the | |
2575 | * block. | |
2576 | */ | |
2577 | if (in_mem) { | |
2578 | struct buffer_head *bitmap_bh; | |
2579 | struct ext3_group_desc *desc; | |
2580 | int inodes_per_buffer; | |
2581 | int inode_offset, i; | |
2582 | int block_group; | |
2583 | int start; | |
2584 | ||
2585 | block_group = (inode->i_ino - 1) / | |
2586 | EXT3_INODES_PER_GROUP(inode->i_sb); | |
2587 | inodes_per_buffer = bh->b_size / | |
2588 | EXT3_INODE_SIZE(inode->i_sb); | |
2589 | inode_offset = ((inode->i_ino - 1) % | |
2590 | EXT3_INODES_PER_GROUP(inode->i_sb)); | |
2591 | start = inode_offset & ~(inodes_per_buffer - 1); | |
2592 | ||
2593 | /* Is the inode bitmap in cache? */ | |
2594 | desc = ext3_get_group_desc(inode->i_sb, | |
2595 | block_group, NULL); | |
2596 | if (!desc) | |
2597 | goto make_io; | |
2598 | ||
2599 | bitmap_bh = sb_getblk(inode->i_sb, | |
2600 | le32_to_cpu(desc->bg_inode_bitmap)); | |
2601 | if (!bitmap_bh) | |
2602 | goto make_io; | |
2603 | ||
2604 | /* | |
2605 | * If the inode bitmap isn't in cache then the | |
2606 | * optimisation may end up performing two reads instead | |
2607 | * of one, so skip it. | |
2608 | */ | |
2609 | if (!buffer_uptodate(bitmap_bh)) { | |
2610 | brelse(bitmap_bh); | |
2611 | goto make_io; | |
2612 | } | |
2613 | for (i = start; i < start + inodes_per_buffer; i++) { | |
2614 | if (i == inode_offset) | |
2615 | continue; | |
2616 | if (ext3_test_bit(i, bitmap_bh->b_data)) | |
2617 | break; | |
2618 | } | |
2619 | brelse(bitmap_bh); | |
2620 | if (i == start + inodes_per_buffer) { | |
2621 | /* all other inodes are free, so skip I/O */ | |
2622 | memset(bh->b_data, 0, bh->b_size); | |
2623 | set_buffer_uptodate(bh); | |
2624 | unlock_buffer(bh); | |
2625 | goto has_buffer; | |
2626 | } | |
2627 | } | |
2628 | ||
2629 | make_io: | |
2630 | /* | |
2631 | * There are other valid inodes in the buffer, this inode | |
2632 | * has in-inode xattrs, or we don't have this inode in memory. | |
2633 | * Read the block from disk. | |
2634 | */ | |
2635 | get_bh(bh); | |
2636 | bh->b_end_io = end_buffer_read_sync; | |
caa38fb0 | 2637 | submit_bh(READ_META, bh); |
1da177e4 LT |
2638 | wait_on_buffer(bh); |
2639 | if (!buffer_uptodate(bh)) { | |
2640 | ext3_error(inode->i_sb, "ext3_get_inode_loc", | |
2641 | "unable to read inode block - " | |
43d23f90 | 2642 | "inode=%lu, block="E3FSBLK, |
1da177e4 LT |
2643 | inode->i_ino, block); |
2644 | brelse(bh); | |
2645 | return -EIO; | |
2646 | } | |
2647 | } | |
2648 | has_buffer: | |
2649 | iloc->bh = bh; | |
2650 | return 0; | |
2651 | } | |
2652 | ||
2653 | int ext3_get_inode_loc(struct inode *inode, struct ext3_iloc *iloc) | |
2654 | { | |
2655 | /* We have all inode data except xattrs in memory here. */ | |
2656 | return __ext3_get_inode_loc(inode, iloc, | |
2657 | !(EXT3_I(inode)->i_state & EXT3_STATE_XATTR)); | |
2658 | } | |
2659 | ||
2660 | void ext3_set_inode_flags(struct inode *inode) | |
2661 | { | |
2662 | unsigned int flags = EXT3_I(inode)->i_flags; | |
2663 | ||
2664 | inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); | |
2665 | if (flags & EXT3_SYNC_FL) | |
2666 | inode->i_flags |= S_SYNC; | |
2667 | if (flags & EXT3_APPEND_FL) | |
2668 | inode->i_flags |= S_APPEND; | |
2669 | if (flags & EXT3_IMMUTABLE_FL) | |
2670 | inode->i_flags |= S_IMMUTABLE; | |
2671 | if (flags & EXT3_NOATIME_FL) | |
2672 | inode->i_flags |= S_NOATIME; | |
2673 | if (flags & EXT3_DIRSYNC_FL) | |
2674 | inode->i_flags |= S_DIRSYNC; | |
2675 | } | |
2676 | ||
28be5abb JK |
2677 | /* Propagate flags from i_flags to EXT3_I(inode)->i_flags */ |
2678 | void ext3_get_inode_flags(struct ext3_inode_info *ei) | |
2679 | { | |
2680 | unsigned int flags = ei->vfs_inode.i_flags; | |
2681 | ||
2682 | ei->i_flags &= ~(EXT3_SYNC_FL|EXT3_APPEND_FL| | |
2683 | EXT3_IMMUTABLE_FL|EXT3_NOATIME_FL|EXT3_DIRSYNC_FL); | |
2684 | if (flags & S_SYNC) | |
2685 | ei->i_flags |= EXT3_SYNC_FL; | |
2686 | if (flags & S_APPEND) | |
2687 | ei->i_flags |= EXT3_APPEND_FL; | |
2688 | if (flags & S_IMMUTABLE) | |
2689 | ei->i_flags |= EXT3_IMMUTABLE_FL; | |
2690 | if (flags & S_NOATIME) | |
2691 | ei->i_flags |= EXT3_NOATIME_FL; | |
2692 | if (flags & S_DIRSYNC) | |
2693 | ei->i_flags |= EXT3_DIRSYNC_FL; | |
2694 | } | |
2695 | ||
473043dc | 2696 | struct inode *ext3_iget(struct super_block *sb, unsigned long ino) |
1da177e4 LT |
2697 | { |
2698 | struct ext3_iloc iloc; | |
2699 | struct ext3_inode *raw_inode; | |
473043dc | 2700 | struct ext3_inode_info *ei; |
1da177e4 | 2701 | struct buffer_head *bh; |
473043dc DH |
2702 | struct inode *inode; |
2703 | long ret; | |
1da177e4 LT |
2704 | int block; |
2705 | ||
473043dc DH |
2706 | inode = iget_locked(sb, ino); |
2707 | if (!inode) | |
2708 | return ERR_PTR(-ENOMEM); | |
2709 | if (!(inode->i_state & I_NEW)) | |
2710 | return inode; | |
2711 | ||
2712 | ei = EXT3_I(inode); | |
1da177e4 LT |
2713 | #ifdef CONFIG_EXT3_FS_POSIX_ACL |
2714 | ei->i_acl = EXT3_ACL_NOT_CACHED; | |
2715 | ei->i_default_acl = EXT3_ACL_NOT_CACHED; | |
2716 | #endif | |
2717 | ei->i_block_alloc_info = NULL; | |
2718 | ||
473043dc DH |
2719 | ret = __ext3_get_inode_loc(inode, &iloc, 0); |
2720 | if (ret < 0) | |
1da177e4 LT |
2721 | goto bad_inode; |
2722 | bh = iloc.bh; | |
2723 | raw_inode = ext3_raw_inode(&iloc); | |
2724 | inode->i_mode = le16_to_cpu(raw_inode->i_mode); | |
2725 | inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); | |
2726 | inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); | |
2727 | if(!(test_opt (inode->i_sb, NO_UID32))) { | |
2728 | inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; | |
2729 | inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; | |
2730 | } | |
2731 | inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); | |
2732 | inode->i_size = le32_to_cpu(raw_inode->i_size); | |
4d7bf11d MR |
2733 | inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime); |
2734 | inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime); | |
2735 | inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime); | |
1da177e4 LT |
2736 | inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0; |
2737 | ||
2738 | ei->i_state = 0; | |
2739 | ei->i_dir_start_lookup = 0; | |
2740 | ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); | |
2741 | /* We now have enough fields to check if the inode was active or not. | |
2742 | * This is needed because nfsd might try to access dead inodes | |
2743 | * the test is that same one that e2fsck uses | |
2744 | * NeilBrown 1999oct15 | |
2745 | */ | |
2746 | if (inode->i_nlink == 0) { | |
2747 | if (inode->i_mode == 0 || | |
2748 | !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ORPHAN_FS)) { | |
2749 | /* this inode is deleted */ | |
2750 | brelse (bh); | |
473043dc | 2751 | ret = -ESTALE; |
1da177e4 LT |
2752 | goto bad_inode; |
2753 | } | |
2754 | /* The only unlinked inodes we let through here have | |
2755 | * valid i_mode and are being read by the orphan | |
2756 | * recovery code: that's fine, we're about to complete | |
2757 | * the process of deleting those. */ | |
2758 | } | |
1da177e4 LT |
2759 | inode->i_blocks = le32_to_cpu(raw_inode->i_blocks); |
2760 | ei->i_flags = le32_to_cpu(raw_inode->i_flags); | |
2761 | #ifdef EXT3_FRAGMENTS | |
2762 | ei->i_faddr = le32_to_cpu(raw_inode->i_faddr); | |
2763 | ei->i_frag_no = raw_inode->i_frag; | |
2764 | ei->i_frag_size = raw_inode->i_fsize; | |
2765 | #endif | |
2766 | ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl); | |
2767 | if (!S_ISREG(inode->i_mode)) { | |
2768 | ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl); | |
2769 | } else { | |
2770 | inode->i_size |= | |
2771 | ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32; | |
2772 | } | |
2773 | ei->i_disksize = inode->i_size; | |
2774 | inode->i_generation = le32_to_cpu(raw_inode->i_generation); | |
2775 | ei->i_block_group = iloc.block_group; | |
2776 | /* | |
2777 | * NOTE! The in-memory inode i_data array is in little-endian order | |
2778 | * even on big-endian machines: we do NOT byteswap the block numbers! | |
2779 | */ | |
2780 | for (block = 0; block < EXT3_N_BLOCKS; block++) | |
2781 | ei->i_data[block] = raw_inode->i_block[block]; | |
2782 | INIT_LIST_HEAD(&ei->i_orphan); | |
2783 | ||
2784 | if (inode->i_ino >= EXT3_FIRST_INO(inode->i_sb) + 1 && | |
2785 | EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) { | |
2786 | /* | |
2787 | * When mke2fs creates big inodes it does not zero out | |
2788 | * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE, | |
2789 | * so ignore those first few inodes. | |
2790 | */ | |
2791 | ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); | |
2792 | if (EXT3_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > | |
e4a10a36 KK |
2793 | EXT3_INODE_SIZE(inode->i_sb)) { |
2794 | brelse (bh); | |
473043dc | 2795 | ret = -EIO; |
1da177e4 | 2796 | goto bad_inode; |
e4a10a36 | 2797 | } |
1da177e4 LT |
2798 | if (ei->i_extra_isize == 0) { |
2799 | /* The extra space is currently unused. Use it. */ | |
2800 | ei->i_extra_isize = sizeof(struct ext3_inode) - | |
2801 | EXT3_GOOD_OLD_INODE_SIZE; | |
2802 | } else { | |
2803 | __le32 *magic = (void *)raw_inode + | |
2804 | EXT3_GOOD_OLD_INODE_SIZE + | |
2805 | ei->i_extra_isize; | |
2806 | if (*magic == cpu_to_le32(EXT3_XATTR_MAGIC)) | |
2807 | ei->i_state |= EXT3_STATE_XATTR; | |
2808 | } | |
2809 | } else | |
2810 | ei->i_extra_isize = 0; | |
2811 | ||
2812 | if (S_ISREG(inode->i_mode)) { | |
2813 | inode->i_op = &ext3_file_inode_operations; | |
2814 | inode->i_fop = &ext3_file_operations; | |
2815 | ext3_set_aops(inode); | |
2816 | } else if (S_ISDIR(inode->i_mode)) { | |
2817 | inode->i_op = &ext3_dir_inode_operations; | |
2818 | inode->i_fop = &ext3_dir_operations; | |
2819 | } else if (S_ISLNK(inode->i_mode)) { | |
2820 | if (ext3_inode_is_fast_symlink(inode)) | |
2821 | inode->i_op = &ext3_fast_symlink_inode_operations; | |
2822 | else { | |
2823 | inode->i_op = &ext3_symlink_inode_operations; | |
2824 | ext3_set_aops(inode); | |
2825 | } | |
2826 | } else { | |
2827 | inode->i_op = &ext3_special_inode_operations; | |
2828 | if (raw_inode->i_block[0]) | |
2829 | init_special_inode(inode, inode->i_mode, | |
2830 | old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); | |
ae6ddcc5 | 2831 | else |
1da177e4 LT |
2832 | init_special_inode(inode, inode->i_mode, |
2833 | new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); | |
2834 | } | |
2835 | brelse (iloc.bh); | |
2836 | ext3_set_inode_flags(inode); | |
473043dc DH |
2837 | unlock_new_inode(inode); |
2838 | return inode; | |
1da177e4 LT |
2839 | |
2840 | bad_inode: | |
473043dc DH |
2841 | iget_failed(inode); |
2842 | return ERR_PTR(ret); | |
1da177e4 LT |
2843 | } |
2844 | ||
2845 | /* | |
2846 | * Post the struct inode info into an on-disk inode location in the | |
2847 | * buffer-cache. This gobbles the caller's reference to the | |
2848 | * buffer_head in the inode location struct. | |
2849 | * | |
2850 | * The caller must have write access to iloc->bh. | |
2851 | */ | |
ae6ddcc5 MC |
2852 | static int ext3_do_update_inode(handle_t *handle, |
2853 | struct inode *inode, | |
1da177e4 LT |
2854 | struct ext3_iloc *iloc) |
2855 | { | |
2856 | struct ext3_inode *raw_inode = ext3_raw_inode(iloc); | |
2857 | struct ext3_inode_info *ei = EXT3_I(inode); | |
2858 | struct buffer_head *bh = iloc->bh; | |
2859 | int err = 0, rc, block; | |
2860 | ||
2861 | /* For fields not not tracking in the in-memory inode, | |
2862 | * initialise them to zero for new inodes. */ | |
2863 | if (ei->i_state & EXT3_STATE_NEW) | |
2864 | memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size); | |
2865 | ||
28be5abb | 2866 | ext3_get_inode_flags(ei); |
1da177e4 LT |
2867 | raw_inode->i_mode = cpu_to_le16(inode->i_mode); |
2868 | if(!(test_opt(inode->i_sb, NO_UID32))) { | |
2869 | raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid)); | |
2870 | raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid)); | |
2871 | /* | |
2872 | * Fix up interoperability with old kernels. Otherwise, old inodes get | |
2873 | * re-used with the upper 16 bits of the uid/gid intact | |
2874 | */ | |
2875 | if(!ei->i_dtime) { | |
2876 | raw_inode->i_uid_high = | |
2877 | cpu_to_le16(high_16_bits(inode->i_uid)); | |
2878 | raw_inode->i_gid_high = | |
2879 | cpu_to_le16(high_16_bits(inode->i_gid)); | |
2880 | } else { | |
2881 | raw_inode->i_uid_high = 0; | |
2882 | raw_inode->i_gid_high = 0; | |
2883 | } | |
2884 | } else { | |
2885 | raw_inode->i_uid_low = | |
2886 | cpu_to_le16(fs_high2lowuid(inode->i_uid)); | |
2887 | raw_inode->i_gid_low = | |
2888 | cpu_to_le16(fs_high2lowgid(inode->i_gid)); | |
2889 | raw_inode->i_uid_high = 0; | |
2890 | raw_inode->i_gid_high = 0; | |
2891 | } | |
2892 | raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); | |
2893 | raw_inode->i_size = cpu_to_le32(ei->i_disksize); | |
2894 | raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec); | |
2895 | raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); | |
2896 | raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); | |
2897 | raw_inode->i_blocks = cpu_to_le32(inode->i_blocks); | |
2898 | raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); | |
2899 | raw_inode->i_flags = cpu_to_le32(ei->i_flags); | |
2900 | #ifdef EXT3_FRAGMENTS | |
2901 | raw_inode->i_faddr = cpu_to_le32(ei->i_faddr); | |
2902 | raw_inode->i_frag = ei->i_frag_no; | |
2903 | raw_inode->i_fsize = ei->i_frag_size; | |
2904 | #endif | |
2905 | raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl); | |
2906 | if (!S_ISREG(inode->i_mode)) { | |
2907 | raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl); | |
2908 | } else { | |
2909 | raw_inode->i_size_high = | |
2910 | cpu_to_le32(ei->i_disksize >> 32); | |
2911 | if (ei->i_disksize > 0x7fffffffULL) { | |
2912 | struct super_block *sb = inode->i_sb; | |
2913 | if (!EXT3_HAS_RO_COMPAT_FEATURE(sb, | |
2914 | EXT3_FEATURE_RO_COMPAT_LARGE_FILE) || | |
2915 | EXT3_SB(sb)->s_es->s_rev_level == | |
2916 | cpu_to_le32(EXT3_GOOD_OLD_REV)) { | |
2917 | /* If this is the first large file | |
2918 | * created, add a flag to the superblock. | |
2919 | */ | |
2920 | err = ext3_journal_get_write_access(handle, | |
2921 | EXT3_SB(sb)->s_sbh); | |
2922 | if (err) | |
2923 | goto out_brelse; | |
2924 | ext3_update_dynamic_rev(sb); | |
2925 | EXT3_SET_RO_COMPAT_FEATURE(sb, | |
2926 | EXT3_FEATURE_RO_COMPAT_LARGE_FILE); | |
2927 | sb->s_dirt = 1; | |
2928 | handle->h_sync = 1; | |
2929 | err = ext3_journal_dirty_metadata(handle, | |
2930 | EXT3_SB(sb)->s_sbh); | |
2931 | } | |
2932 | } | |
2933 | } | |
2934 | raw_inode->i_generation = cpu_to_le32(inode->i_generation); | |
2935 | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { | |
2936 | if (old_valid_dev(inode->i_rdev)) { | |
2937 | raw_inode->i_block[0] = | |
2938 | cpu_to_le32(old_encode_dev(inode->i_rdev)); | |
2939 | raw_inode->i_block[1] = 0; | |
2940 | } else { | |
2941 | raw_inode->i_block[0] = 0; | |
2942 | raw_inode->i_block[1] = | |
2943 | cpu_to_le32(new_encode_dev(inode->i_rdev)); | |
2944 | raw_inode->i_block[2] = 0; | |
2945 | } | |
2946 | } else for (block = 0; block < EXT3_N_BLOCKS; block++) | |
2947 | raw_inode->i_block[block] = ei->i_data[block]; | |
2948 | ||
ff87b37d | 2949 | if (ei->i_extra_isize) |
1da177e4 LT |
2950 | raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); |
2951 | ||
2952 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
2953 | rc = ext3_journal_dirty_metadata(handle, bh); | |
2954 | if (!err) | |
2955 | err = rc; | |
2956 | ei->i_state &= ~EXT3_STATE_NEW; | |
2957 | ||
2958 | out_brelse: | |
2959 | brelse (bh); | |
2960 | ext3_std_error(inode->i_sb, err); | |
2961 | return err; | |
2962 | } | |
2963 | ||
2964 | /* | |
2965 | * ext3_write_inode() | |
2966 | * | |
2967 | * We are called from a few places: | |
2968 | * | |
2969 | * - Within generic_file_write() for O_SYNC files. | |
2970 | * Here, there will be no transaction running. We wait for any running | |
2971 | * trasnaction to commit. | |
2972 | * | |
2973 | * - Within sys_sync(), kupdate and such. | |
2974 | * We wait on commit, if tol to. | |
2975 | * | |
2976 | * - Within prune_icache() (PF_MEMALLOC == true) | |
2977 | * Here we simply return. We can't afford to block kswapd on the | |
2978 | * journal commit. | |
2979 | * | |
2980 | * In all cases it is actually safe for us to return without doing anything, | |
2981 | * because the inode has been copied into a raw inode buffer in | |
2982 | * ext3_mark_inode_dirty(). This is a correctness thing for O_SYNC and for | |
2983 | * knfsd. | |
2984 | * | |
2985 | * Note that we are absolutely dependent upon all inode dirtiers doing the | |
2986 | * right thing: they *must* call mark_inode_dirty() after dirtying info in | |
2987 | * which we are interested. | |
2988 | * | |
2989 | * It would be a bug for them to not do this. The code: | |
2990 | * | |
2991 | * mark_inode_dirty(inode) | |
2992 | * stuff(); | |
2993 | * inode->i_size = expr; | |
2994 | * | |
2995 | * is in error because a kswapd-driven write_inode() could occur while | |
2996 | * `stuff()' is running, and the new i_size will be lost. Plus the inode | |
2997 | * will no longer be on the superblock's dirty inode list. | |
2998 | */ | |
2999 | int ext3_write_inode(struct inode *inode, int wait) | |
3000 | { | |
3001 | if (current->flags & PF_MEMALLOC) | |
3002 | return 0; | |
3003 | ||
3004 | if (ext3_journal_current_handle()) { | |
9ad163ae | 3005 | jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n"); |
1da177e4 LT |
3006 | dump_stack(); |
3007 | return -EIO; | |
3008 | } | |
3009 | ||
3010 | if (!wait) | |
3011 | return 0; | |
3012 | ||
3013 | return ext3_force_commit(inode->i_sb); | |
3014 | } | |
3015 | ||
3016 | /* | |
3017 | * ext3_setattr() | |
3018 | * | |
3019 | * Called from notify_change. | |
3020 | * | |
3021 | * We want to trap VFS attempts to truncate the file as soon as | |
3022 | * possible. In particular, we want to make sure that when the VFS | |
3023 | * shrinks i_size, we put the inode on the orphan list and modify | |
3024 | * i_disksize immediately, so that during the subsequent flushing of | |
3025 | * dirty pages and freeing of disk blocks, we can guarantee that any | |
3026 | * commit will leave the blocks being flushed in an unused state on | |
3027 | * disk. (On recovery, the inode will get truncated and the blocks will | |
3028 | * be freed, so we have a strong guarantee that no future commit will | |
ae6ddcc5 | 3029 | * leave these blocks visible to the user.) |
1da177e4 LT |
3030 | * |
3031 | * Called with inode->sem down. | |
3032 | */ | |
3033 | int ext3_setattr(struct dentry *dentry, struct iattr *attr) | |
3034 | { | |
3035 | struct inode *inode = dentry->d_inode; | |
3036 | int error, rc = 0; | |
3037 | const unsigned int ia_valid = attr->ia_valid; | |
3038 | ||
3039 | error = inode_change_ok(inode, attr); | |
3040 | if (error) | |
3041 | return error; | |
3042 | ||
3043 | if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || | |
3044 | (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) { | |
3045 | handle_t *handle; | |
3046 | ||
3047 | /* (user+group)*(old+new) structure, inode write (sb, | |
3048 | * inode block, ? - but truncate inode update has it) */ | |
1f54587b JK |
3049 | handle = ext3_journal_start(inode, 2*(EXT3_QUOTA_INIT_BLOCKS(inode->i_sb)+ |
3050 | EXT3_QUOTA_DEL_BLOCKS(inode->i_sb))+3); | |
1da177e4 LT |
3051 | if (IS_ERR(handle)) { |
3052 | error = PTR_ERR(handle); | |
3053 | goto err_out; | |
3054 | } | |
3055 | error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0; | |
3056 | if (error) { | |
3057 | ext3_journal_stop(handle); | |
3058 | return error; | |
3059 | } | |
3060 | /* Update corresponding info in inode so that everything is in | |
3061 | * one transaction */ | |
3062 | if (attr->ia_valid & ATTR_UID) | |
3063 | inode->i_uid = attr->ia_uid; | |
3064 | if (attr->ia_valid & ATTR_GID) | |
3065 | inode->i_gid = attr->ia_gid; | |
3066 | error = ext3_mark_inode_dirty(handle, inode); | |
3067 | ext3_journal_stop(handle); | |
3068 | } | |
3069 | ||
3070 | if (S_ISREG(inode->i_mode) && | |
3071 | attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { | |
3072 | handle_t *handle; | |
3073 | ||
3074 | handle = ext3_journal_start(inode, 3); | |
3075 | if (IS_ERR(handle)) { | |
3076 | error = PTR_ERR(handle); | |
3077 | goto err_out; | |
3078 | } | |
3079 | ||
3080 | error = ext3_orphan_add(handle, inode); | |
3081 | EXT3_I(inode)->i_disksize = attr->ia_size; | |
3082 | rc = ext3_mark_inode_dirty(handle, inode); | |
3083 | if (!error) | |
3084 | error = rc; | |
3085 | ext3_journal_stop(handle); | |
3086 | } | |
3087 | ||
3088 | rc = inode_setattr(inode, attr); | |
3089 | ||
3090 | /* If inode_setattr's call to ext3_truncate failed to get a | |
3091 | * transaction handle at all, we need to clean up the in-core | |
3092 | * orphan list manually. */ | |
3093 | if (inode->i_nlink) | |
3094 | ext3_orphan_del(NULL, inode); | |
3095 | ||
3096 | if (!rc && (ia_valid & ATTR_MODE)) | |
3097 | rc = ext3_acl_chmod(inode); | |
3098 | ||
3099 | err_out: | |
3100 | ext3_std_error(inode->i_sb, error); | |
3101 | if (!error) | |
3102 | error = rc; | |
3103 | return error; | |
3104 | } | |
3105 | ||
3106 | ||
3107 | /* | |
d6859bfc | 3108 | * How many blocks doth make a writepage()? |
1da177e4 LT |
3109 | * |
3110 | * With N blocks per page, it may be: | |
3111 | * N data blocks | |
3112 | * 2 indirect block | |
3113 | * 2 dindirect | |
3114 | * 1 tindirect | |
3115 | * N+5 bitmap blocks (from the above) | |
3116 | * N+5 group descriptor summary blocks | |
3117 | * 1 inode block | |
3118 | * 1 superblock. | |
3119 | * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files | |
3120 | * | |
3121 | * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS | |
3122 | * | |
3123 | * With ordered or writeback data it's the same, less the N data blocks. | |
3124 | * | |
3125 | * If the inode's direct blocks can hold an integral number of pages then a | |
3126 | * page cannot straddle two indirect blocks, and we can only touch one indirect | |
3127 | * and dindirect block, and the "5" above becomes "3". | |
3128 | * | |
3129 | * This still overestimates under most circumstances. If we were to pass the | |
3130 | * start and end offsets in here as well we could do block_to_path() on each | |
3131 | * block and work out the exact number of indirects which are touched. Pah. | |
3132 | */ | |
3133 | ||
3134 | static int ext3_writepage_trans_blocks(struct inode *inode) | |
3135 | { | |
3136 | int bpp = ext3_journal_blocks_per_page(inode); | |
3137 | int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3; | |
3138 | int ret; | |
3139 | ||
3140 | if (ext3_should_journal_data(inode)) | |
3141 | ret = 3 * (bpp + indirects) + 2; | |
3142 | else | |
3143 | ret = 2 * (bpp + indirects) + 2; | |
3144 | ||
3145 | #ifdef CONFIG_QUOTA | |
3146 | /* We know that structure was already allocated during DQUOT_INIT so | |
3147 | * we will be updating only the data blocks + inodes */ | |
1f54587b | 3148 | ret += 2*EXT3_QUOTA_TRANS_BLOCKS(inode->i_sb); |
1da177e4 LT |
3149 | #endif |
3150 | ||
3151 | return ret; | |
3152 | } | |
3153 | ||
3154 | /* | |
3155 | * The caller must have previously called ext3_reserve_inode_write(). | |
3156 | * Give this, we know that the caller already has write access to iloc->bh. | |
3157 | */ | |
3158 | int ext3_mark_iloc_dirty(handle_t *handle, | |
3159 | struct inode *inode, struct ext3_iloc *iloc) | |
3160 | { | |
3161 | int err = 0; | |
3162 | ||
3163 | /* the do_update_inode consumes one bh->b_count */ | |
3164 | get_bh(iloc->bh); | |
3165 | ||
3166 | /* ext3_do_update_inode() does journal_dirty_metadata */ | |
3167 | err = ext3_do_update_inode(handle, inode, iloc); | |
3168 | put_bh(iloc->bh); | |
3169 | return err; | |
3170 | } | |
3171 | ||
ae6ddcc5 | 3172 | /* |
1da177e4 | 3173 | * On success, We end up with an outstanding reference count against |
ae6ddcc5 | 3174 | * iloc->bh. This _must_ be cleaned up later. |
1da177e4 LT |
3175 | */ |
3176 | ||
3177 | int | |
ae6ddcc5 | 3178 | ext3_reserve_inode_write(handle_t *handle, struct inode *inode, |
1da177e4 LT |
3179 | struct ext3_iloc *iloc) |
3180 | { | |
3181 | int err = 0; | |
3182 | if (handle) { | |
3183 | err = ext3_get_inode_loc(inode, iloc); | |
3184 | if (!err) { | |
3185 | BUFFER_TRACE(iloc->bh, "get_write_access"); | |
3186 | err = ext3_journal_get_write_access(handle, iloc->bh); | |
3187 | if (err) { | |
3188 | brelse(iloc->bh); | |
3189 | iloc->bh = NULL; | |
3190 | } | |
3191 | } | |
3192 | } | |
3193 | ext3_std_error(inode->i_sb, err); | |
3194 | return err; | |
3195 | } | |
3196 | ||
3197 | /* | |
d6859bfc AM |
3198 | * What we do here is to mark the in-core inode as clean with respect to inode |
3199 | * dirtiness (it may still be data-dirty). | |
1da177e4 LT |
3200 | * This means that the in-core inode may be reaped by prune_icache |
3201 | * without having to perform any I/O. This is a very good thing, | |
3202 | * because *any* task may call prune_icache - even ones which | |
3203 | * have a transaction open against a different journal. | |
3204 | * | |
3205 | * Is this cheating? Not really. Sure, we haven't written the | |
3206 | * inode out, but prune_icache isn't a user-visible syncing function. | |
3207 | * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) | |
3208 | * we start and wait on commits. | |
3209 | * | |
3210 | * Is this efficient/effective? Well, we're being nice to the system | |
3211 | * by cleaning up our inodes proactively so they can be reaped | |
3212 | * without I/O. But we are potentially leaving up to five seconds' | |
3213 | * worth of inodes floating about which prune_icache wants us to | |
3214 | * write out. One way to fix that would be to get prune_icache() | |
3215 | * to do a write_super() to free up some memory. It has the desired | |
3216 | * effect. | |
3217 | */ | |
3218 | int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode) | |
3219 | { | |
3220 | struct ext3_iloc iloc; | |
3221 | int err; | |
3222 | ||
3223 | might_sleep(); | |
3224 | err = ext3_reserve_inode_write(handle, inode, &iloc); | |
3225 | if (!err) | |
3226 | err = ext3_mark_iloc_dirty(handle, inode, &iloc); | |
3227 | return err; | |
3228 | } | |
3229 | ||
3230 | /* | |
d6859bfc | 3231 | * ext3_dirty_inode() is called from __mark_inode_dirty() |
1da177e4 LT |
3232 | * |
3233 | * We're really interested in the case where a file is being extended. | |
3234 | * i_size has been changed by generic_commit_write() and we thus need | |
3235 | * to include the updated inode in the current transaction. | |
3236 | * | |
3237 | * Also, DQUOT_ALLOC_SPACE() will always dirty the inode when blocks | |
3238 | * are allocated to the file. | |
3239 | * | |
3240 | * If the inode is marked synchronous, we don't honour that here - doing | |
3241 | * so would cause a commit on atime updates, which we don't bother doing. | |
3242 | * We handle synchronous inodes at the highest possible level. | |
3243 | */ | |
3244 | void ext3_dirty_inode(struct inode *inode) | |
3245 | { | |
3246 | handle_t *current_handle = ext3_journal_current_handle(); | |
3247 | handle_t *handle; | |
3248 | ||
3249 | handle = ext3_journal_start(inode, 2); | |
3250 | if (IS_ERR(handle)) | |
3251 | goto out; | |
3252 | if (current_handle && | |
3253 | current_handle->h_transaction != handle->h_transaction) { | |
3254 | /* This task has a transaction open against a different fs */ | |
3255 | printk(KERN_EMERG "%s: transactions do not match!\n", | |
e05b6b52 | 3256 | __func__); |
1da177e4 LT |
3257 | } else { |
3258 | jbd_debug(5, "marking dirty. outer handle=%p\n", | |
3259 | current_handle); | |
3260 | ext3_mark_inode_dirty(handle, inode); | |
3261 | } | |
3262 | ext3_journal_stop(handle); | |
3263 | out: | |
3264 | return; | |
3265 | } | |
3266 | ||
d6859bfc | 3267 | #if 0 |
ae6ddcc5 | 3268 | /* |
1da177e4 LT |
3269 | * Bind an inode's backing buffer_head into this transaction, to prevent |
3270 | * it from being flushed to disk early. Unlike | |
3271 | * ext3_reserve_inode_write, this leaves behind no bh reference and | |
3272 | * returns no iloc structure, so the caller needs to repeat the iloc | |
3273 | * lookup to mark the inode dirty later. | |
3274 | */ | |
d6859bfc | 3275 | static int ext3_pin_inode(handle_t *handle, struct inode *inode) |
1da177e4 LT |
3276 | { |
3277 | struct ext3_iloc iloc; | |
3278 | ||
3279 | int err = 0; | |
3280 | if (handle) { | |
3281 | err = ext3_get_inode_loc(inode, &iloc); | |
3282 | if (!err) { | |
3283 | BUFFER_TRACE(iloc.bh, "get_write_access"); | |
3284 | err = journal_get_write_access(handle, iloc.bh); | |
3285 | if (!err) | |
ae6ddcc5 | 3286 | err = ext3_journal_dirty_metadata(handle, |
1da177e4 LT |
3287 | iloc.bh); |
3288 | brelse(iloc.bh); | |
3289 | } | |
3290 | } | |
3291 | ext3_std_error(inode->i_sb, err); | |
3292 | return err; | |
3293 | } | |
3294 | #endif | |
3295 | ||
3296 | int ext3_change_inode_journal_flag(struct inode *inode, int val) | |
3297 | { | |
3298 | journal_t *journal; | |
3299 | handle_t *handle; | |
3300 | int err; | |
3301 | ||
3302 | /* | |
3303 | * We have to be very careful here: changing a data block's | |
3304 | * journaling status dynamically is dangerous. If we write a | |
3305 | * data block to the journal, change the status and then delete | |
3306 | * that block, we risk forgetting to revoke the old log record | |
3307 | * from the journal and so a subsequent replay can corrupt data. | |
3308 | * So, first we make sure that the journal is empty and that | |
3309 | * nobody is changing anything. | |
3310 | */ | |
3311 | ||
3312 | journal = EXT3_JOURNAL(inode); | |
e3a68e30 | 3313 | if (is_journal_aborted(journal)) |
1da177e4 LT |
3314 | return -EROFS; |
3315 | ||
3316 | journal_lock_updates(journal); | |
3317 | journal_flush(journal); | |
3318 | ||
3319 | /* | |
3320 | * OK, there are no updates running now, and all cached data is | |
3321 | * synced to disk. We are now in a completely consistent state | |
3322 | * which doesn't have anything in the journal, and we know that | |
3323 | * no filesystem updates are running, so it is safe to modify | |
3324 | * the inode's in-core data-journaling state flag now. | |
3325 | */ | |
3326 | ||
3327 | if (val) | |
3328 | EXT3_I(inode)->i_flags |= EXT3_JOURNAL_DATA_FL; | |
3329 | else | |
3330 | EXT3_I(inode)->i_flags &= ~EXT3_JOURNAL_DATA_FL; | |
3331 | ext3_set_aops(inode); | |
3332 | ||
3333 | journal_unlock_updates(journal); | |
3334 | ||
3335 | /* Finally we can mark the inode as dirty. */ | |
3336 | ||
3337 | handle = ext3_journal_start(inode, 1); | |
3338 | if (IS_ERR(handle)) | |
3339 | return PTR_ERR(handle); | |
3340 | ||
3341 | err = ext3_mark_inode_dirty(handle, inode); | |
3342 | handle->h_sync = 1; | |
3343 | ext3_journal_stop(handle); | |
3344 | ext3_std_error(inode->i_sb, err); | |
3345 | ||
3346 | return err; | |
3347 | } |