Commit | Line | Data |
---|---|---|
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> |
b5ed3112 | 40 | #include <linux/namei.h> |
1da177e4 LT |
41 | #include "xattr.h" |
42 | #include "acl.h" | |
43 | ||
44 | static int ext3_writepage_trans_blocks(struct inode *inode); | |
45 | ||
46 | /* | |
47 | * Test whether an inode is a fast symlink. | |
48 | */ | |
d6859bfc | 49 | static int ext3_inode_is_fast_symlink(struct inode *inode) |
1da177e4 LT |
50 | { |
51 | int ea_blocks = EXT3_I(inode)->i_file_acl ? | |
52 | (inode->i_sb->s_blocksize >> 9) : 0; | |
53 | ||
d6859bfc | 54 | return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); |
1da177e4 LT |
55 | } |
56 | ||
d6859bfc AM |
57 | /* |
58 | * The ext3 forget function must perform a revoke if we are freeing data | |
1da177e4 | 59 | * which has been journaled. Metadata (eg. indirect blocks) must be |
ae6ddcc5 | 60 | * revoked in all cases. |
1da177e4 LT |
61 | * |
62 | * "bh" may be NULL: a metadata block may have been freed from memory | |
63 | * but there may still be a record of it in the journal, and that record | |
64 | * still needs to be revoked. | |
65 | */ | |
d6859bfc | 66 | int ext3_forget(handle_t *handle, int is_metadata, struct inode *inode, |
1c2bf374 | 67 | struct buffer_head *bh, ext3_fsblk_t blocknr) |
1da177e4 LT |
68 | { |
69 | int err; | |
70 | ||
71 | might_sleep(); | |
72 | ||
73 | BUFFER_TRACE(bh, "enter"); | |
74 | ||
75 | jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " | |
76 | "data mode %lx\n", | |
77 | bh, is_metadata, inode->i_mode, | |
78 | test_opt(inode->i_sb, DATA_FLAGS)); | |
79 | ||
80 | /* Never use the revoke function if we are doing full data | |
81 | * journaling: there is no need to, and a V1 superblock won't | |
82 | * support it. Otherwise, only skip the revoke on un-journaled | |
83 | * data blocks. */ | |
84 | ||
85 | if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA || | |
86 | (!is_metadata && !ext3_should_journal_data(inode))) { | |
87 | if (bh) { | |
88 | BUFFER_TRACE(bh, "call journal_forget"); | |
89 | return ext3_journal_forget(handle, bh); | |
90 | } | |
91 | return 0; | |
92 | } | |
93 | ||
94 | /* | |
95 | * data!=journal && (is_metadata || should_journal_data(inode)) | |
96 | */ | |
97 | BUFFER_TRACE(bh, "call ext3_journal_revoke"); | |
98 | err = ext3_journal_revoke(handle, blocknr, bh); | |
99 | if (err) | |
e05b6b52 | 100 | ext3_abort(inode->i_sb, __func__, |
1da177e4 LT |
101 | "error %d when attempting revoke", err); |
102 | BUFFER_TRACE(bh, "exit"); | |
103 | return err; | |
104 | } | |
105 | ||
106 | /* | |
d6859bfc | 107 | * Work out how many blocks we need to proceed with the next chunk of a |
1da177e4 LT |
108 | * truncate transaction. |
109 | */ | |
ae6ddcc5 | 110 | static unsigned long blocks_for_truncate(struct inode *inode) |
1da177e4 LT |
111 | { |
112 | unsigned long needed; | |
113 | ||
114 | needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); | |
115 | ||
116 | /* Give ourselves just enough room to cope with inodes in which | |
117 | * i_blocks is corrupt: we've seen disk corruptions in the past | |
118 | * which resulted in random data in an inode which looked enough | |
119 | * like a regular file for ext3 to try to delete it. Things | |
120 | * will go a bit crazy if that happens, but at least we should | |
121 | * try not to panic the whole kernel. */ | |
122 | if (needed < 2) | |
123 | needed = 2; | |
124 | ||
125 | /* But we need to bound the transaction so we don't overflow the | |
126 | * journal. */ | |
ae6ddcc5 | 127 | if (needed > EXT3_MAX_TRANS_DATA) |
1da177e4 LT |
128 | needed = EXT3_MAX_TRANS_DATA; |
129 | ||
1f54587b | 130 | return EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + needed; |
1da177e4 LT |
131 | } |
132 | ||
ae6ddcc5 | 133 | /* |
1da177e4 LT |
134 | * Truncate transactions can be complex and absolutely huge. So we need to |
135 | * be able to restart the transaction at a conventient checkpoint to make | |
136 | * sure we don't overflow the journal. | |
137 | * | |
138 | * start_transaction gets us a new handle for a truncate transaction, | |
139 | * and extend_transaction tries to extend the existing one a bit. If | |
140 | * extend fails, we need to propagate the failure up and restart the | |
ae6ddcc5 | 141 | * transaction in the top-level truncate loop. --sct |
1da177e4 | 142 | */ |
ae6ddcc5 | 143 | static handle_t *start_transaction(struct inode *inode) |
1da177e4 LT |
144 | { |
145 | handle_t *result; | |
146 | ||
147 | result = ext3_journal_start(inode, blocks_for_truncate(inode)); | |
148 | if (!IS_ERR(result)) | |
149 | return result; | |
150 | ||
151 | ext3_std_error(inode->i_sb, PTR_ERR(result)); | |
152 | return result; | |
153 | } | |
154 | ||
155 | /* | |
156 | * Try to extend this transaction for the purposes of truncation. | |
157 | * | |
158 | * Returns 0 if we managed to create more room. If we can't create more | |
159 | * room, and the transaction must be restarted we return 1. | |
160 | */ | |
161 | static int try_to_extend_transaction(handle_t *handle, struct inode *inode) | |
162 | { | |
163 | if (handle->h_buffer_credits > EXT3_RESERVE_TRANS_BLOCKS) | |
164 | return 0; | |
165 | if (!ext3_journal_extend(handle, blocks_for_truncate(inode))) | |
166 | return 0; | |
167 | return 1; | |
168 | } | |
169 | ||
170 | /* | |
171 | * Restart the transaction associated with *handle. This does a commit, | |
172 | * so before we call here everything must be consistently dirtied against | |
173 | * this transaction. | |
174 | */ | |
00171d3c | 175 | static int truncate_restart_transaction(handle_t *handle, struct inode *inode) |
1da177e4 | 176 | { |
00171d3c JK |
177 | int ret; |
178 | ||
1da177e4 | 179 | jbd_debug(2, "restarting handle %p\n", handle); |
00171d3c JK |
180 | /* |
181 | * Drop truncate_mutex to avoid deadlock with ext3_get_blocks_handle | |
182 | * At this moment, get_block can be called only for blocks inside | |
183 | * i_size since page cache has been already dropped and writes are | |
184 | * blocked by i_mutex. So we can safely drop the truncate_mutex. | |
185 | */ | |
186 | mutex_unlock(&EXT3_I(inode)->truncate_mutex); | |
187 | ret = ext3_journal_restart(handle, blocks_for_truncate(inode)); | |
188 | mutex_lock(&EXT3_I(inode)->truncate_mutex); | |
189 | return ret; | |
1da177e4 LT |
190 | } |
191 | ||
192 | /* | |
193 | * Called at the last iput() if i_nlink is zero. | |
194 | */ | |
195 | void ext3_delete_inode (struct inode * inode) | |
196 | { | |
197 | handle_t *handle; | |
198 | ||
907f4554 | 199 | if (!is_bad_inode(inode)) |
871a2931 | 200 | dquot_initialize(inode); |
907f4554 | 201 | |
fef26658 MF |
202 | truncate_inode_pages(&inode->i_data, 0); |
203 | ||
1da177e4 LT |
204 | if (is_bad_inode(inode)) |
205 | goto no_delete; | |
206 | ||
207 | handle = start_transaction(inode); | |
208 | if (IS_ERR(handle)) { | |
d6859bfc AM |
209 | /* |
210 | * If we're going to skip the normal cleanup, we still need to | |
211 | * make sure that the in-core orphan linked list is properly | |
212 | * cleaned up. | |
213 | */ | |
1da177e4 LT |
214 | ext3_orphan_del(NULL, inode); |
215 | goto no_delete; | |
216 | } | |
217 | ||
218 | if (IS_SYNC(inode)) | |
219 | handle->h_sync = 1; | |
220 | inode->i_size = 0; | |
221 | if (inode->i_blocks) | |
222 | ext3_truncate(inode); | |
223 | /* | |
224 | * Kill off the orphan record which ext3_truncate created. | |
225 | * AKPM: I think this can be inside the above `if'. | |
226 | * Note that ext3_orphan_del() has to be able to cope with the | |
227 | * deletion of a non-existent orphan - this is because we don't | |
228 | * know if ext3_truncate() actually created an orphan record. | |
229 | * (Well, we could do this if we need to, but heck - it works) | |
230 | */ | |
231 | ext3_orphan_del(handle, inode); | |
232 | EXT3_I(inode)->i_dtime = get_seconds(); | |
233 | ||
ae6ddcc5 | 234 | /* |
1da177e4 LT |
235 | * One subtle ordering requirement: if anything has gone wrong |
236 | * (transaction abort, IO errors, whatever), then we can still | |
237 | * do these next steps (the fs will already have been marked as | |
238 | * having errors), but we can't free the inode if the mark_dirty | |
ae6ddcc5 | 239 | * fails. |
1da177e4 LT |
240 | */ |
241 | if (ext3_mark_inode_dirty(handle, inode)) | |
242 | /* If that failed, just do the required in-core inode clear. */ | |
243 | clear_inode(inode); | |
244 | else | |
245 | ext3_free_inode(handle, inode); | |
246 | ext3_journal_stop(handle); | |
247 | return; | |
248 | no_delete: | |
249 | clear_inode(inode); /* We must guarantee clearing of inode... */ | |
250 | } | |
251 | ||
1da177e4 LT |
252 | typedef struct { |
253 | __le32 *p; | |
254 | __le32 key; | |
255 | struct buffer_head *bh; | |
256 | } Indirect; | |
257 | ||
258 | static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) | |
259 | { | |
260 | p->key = *(p->p = v); | |
261 | p->bh = bh; | |
262 | } | |
263 | ||
d6859bfc | 264 | static int verify_chain(Indirect *from, Indirect *to) |
1da177e4 LT |
265 | { |
266 | while (from <= to && from->key == *from->p) | |
267 | from++; | |
268 | return (from > to); | |
269 | } | |
270 | ||
271 | /** | |
272 | * ext3_block_to_path - parse the block number into array of offsets | |
273 | * @inode: inode in question (we are only interested in its superblock) | |
274 | * @i_block: block number to be parsed | |
275 | * @offsets: array to store the offsets in | |
276 | * @boundary: set this non-zero if the referred-to block is likely to be | |
277 | * followed (on disk) by an indirect block. | |
278 | * | |
279 | * To store the locations of file's data ext3 uses a data structure common | |
280 | * for UNIX filesystems - tree of pointers anchored in the inode, with | |
281 | * data blocks at leaves and indirect blocks in intermediate nodes. | |
282 | * This function translates the block number into path in that tree - | |
283 | * return value is the path length and @offsets[n] is the offset of | |
284 | * pointer to (n+1)th node in the nth one. If @block is out of range | |
285 | * (negative or too large) warning is printed and zero returned. | |
286 | * | |
287 | * Note: function doesn't find node addresses, so no IO is needed. All | |
288 | * we need to know is the capacity of indirect blocks (taken from the | |
289 | * inode->i_sb). | |
290 | */ | |
291 | ||
292 | /* | |
293 | * Portability note: the last comparison (check that we fit into triple | |
294 | * indirect block) is spelled differently, because otherwise on an | |
295 | * architecture with 32-bit longs and 8Kb pages we might get into trouble | |
296 | * if our filesystem had 8Kb blocks. We might use long long, but that would | |
297 | * kill us on x86. Oh, well, at least the sign propagation does not matter - | |
298 | * i_block would have to be negative in the very beginning, so we would not | |
299 | * get there at all. | |
300 | */ | |
301 | ||
302 | static int ext3_block_to_path(struct inode *inode, | |
303 | long i_block, int offsets[4], int *boundary) | |
304 | { | |
305 | int ptrs = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
306 | int ptrs_bits = EXT3_ADDR_PER_BLOCK_BITS(inode->i_sb); | |
307 | const long direct_blocks = EXT3_NDIR_BLOCKS, | |
308 | indirect_blocks = ptrs, | |
309 | double_blocks = (1 << (ptrs_bits * 2)); | |
310 | int n = 0; | |
311 | int final = 0; | |
312 | ||
313 | if (i_block < 0) { | |
314 | ext3_warning (inode->i_sb, "ext3_block_to_path", "block < 0"); | |
315 | } else if (i_block < direct_blocks) { | |
316 | offsets[n++] = i_block; | |
317 | final = direct_blocks; | |
318 | } else if ( (i_block -= direct_blocks) < indirect_blocks) { | |
319 | offsets[n++] = EXT3_IND_BLOCK; | |
320 | offsets[n++] = i_block; | |
321 | final = ptrs; | |
322 | } else if ((i_block -= indirect_blocks) < double_blocks) { | |
323 | offsets[n++] = EXT3_DIND_BLOCK; | |
324 | offsets[n++] = i_block >> ptrs_bits; | |
325 | offsets[n++] = i_block & (ptrs - 1); | |
326 | final = ptrs; | |
327 | } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { | |
328 | offsets[n++] = EXT3_TIND_BLOCK; | |
329 | offsets[n++] = i_block >> (ptrs_bits * 2); | |
330 | offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); | |
331 | offsets[n++] = i_block & (ptrs - 1); | |
332 | final = ptrs; | |
333 | } else { | |
d6859bfc | 334 | ext3_warning(inode->i_sb, "ext3_block_to_path", "block > big"); |
1da177e4 LT |
335 | } |
336 | if (boundary) | |
89747d36 | 337 | *boundary = final - 1 - (i_block & (ptrs - 1)); |
1da177e4 LT |
338 | return n; |
339 | } | |
340 | ||
341 | /** | |
342 | * ext3_get_branch - read the chain of indirect blocks leading to data | |
343 | * @inode: inode in question | |
344 | * @depth: depth of the chain (1 - direct pointer, etc.) | |
345 | * @offsets: offsets of pointers in inode/indirect blocks | |
346 | * @chain: place to store the result | |
347 | * @err: here we store the error value | |
348 | * | |
349 | * Function fills the array of triples <key, p, bh> and returns %NULL | |
350 | * if everything went OK or the pointer to the last filled triple | |
351 | * (incomplete one) otherwise. Upon the return chain[i].key contains | |
352 | * the number of (i+1)-th block in the chain (as it is stored in memory, | |
353 | * i.e. little-endian 32-bit), chain[i].p contains the address of that | |
354 | * number (it points into struct inode for i==0 and into the bh->b_data | |
355 | * for i>0) and chain[i].bh points to the buffer_head of i-th indirect | |
356 | * block for i>0 and NULL for i==0. In other words, it holds the block | |
357 | * numbers of the chain, addresses they were taken from (and where we can | |
358 | * verify that chain did not change) and buffer_heads hosting these | |
359 | * numbers. | |
360 | * | |
361 | * Function stops when it stumbles upon zero pointer (absent block) | |
362 | * (pointer to last triple returned, *@err == 0) | |
363 | * or when it gets an IO error reading an indirect block | |
364 | * (ditto, *@err == -EIO) | |
365 | * or when it notices that chain had been changed while it was reading | |
366 | * (ditto, *@err == -EAGAIN) | |
367 | * or when it reads all @depth-1 indirect blocks successfully and finds | |
368 | * the whole chain, all way to the data (returns %NULL, *err == 0). | |
369 | */ | |
370 | static Indirect *ext3_get_branch(struct inode *inode, int depth, int *offsets, | |
371 | Indirect chain[4], int *err) | |
372 | { | |
373 | struct super_block *sb = inode->i_sb; | |
374 | Indirect *p = chain; | |
375 | struct buffer_head *bh; | |
376 | ||
377 | *err = 0; | |
378 | /* i_data is not going away, no lock needed */ | |
379 | add_chain (chain, NULL, EXT3_I(inode)->i_data + *offsets); | |
380 | if (!p->key) | |
381 | goto no_block; | |
382 | while (--depth) { | |
383 | bh = sb_bread(sb, le32_to_cpu(p->key)); | |
384 | if (!bh) | |
385 | goto failure; | |
386 | /* Reader: pointers */ | |
387 | if (!verify_chain(chain, p)) | |
388 | goto changed; | |
389 | add_chain(++p, bh, (__le32*)bh->b_data + *++offsets); | |
390 | /* Reader: end */ | |
391 | if (!p->key) | |
392 | goto no_block; | |
393 | } | |
394 | return NULL; | |
395 | ||
396 | changed: | |
397 | brelse(bh); | |
398 | *err = -EAGAIN; | |
399 | goto no_block; | |
400 | failure: | |
401 | *err = -EIO; | |
402 | no_block: | |
403 | return p; | |
404 | } | |
405 | ||
406 | /** | |
407 | * ext3_find_near - find a place for allocation with sufficient locality | |
408 | * @inode: owner | |
409 | * @ind: descriptor of indirect block. | |
410 | * | |
1cc8dcf5 | 411 | * This function returns the preferred place for block allocation. |
1da177e4 LT |
412 | * It is used when heuristic for sequential allocation fails. |
413 | * Rules are: | |
414 | * + if there is a block to the left of our position - allocate near it. | |
415 | * + if pointer will live in indirect block - allocate near that block. | |
416 | * + if pointer will live in inode - allocate in the same | |
ae6ddcc5 | 417 | * cylinder group. |
1da177e4 LT |
418 | * |
419 | * In the latter case we colour the starting block by the callers PID to | |
420 | * prevent it from clashing with concurrent allocations for a different inode | |
421 | * in the same block group. The PID is used here so that functionally related | |
422 | * files will be close-by on-disk. | |
423 | * | |
424 | * Caller must make sure that @ind is valid and will stay that way. | |
425 | */ | |
43d23f90 | 426 | static ext3_fsblk_t ext3_find_near(struct inode *inode, Indirect *ind) |
1da177e4 LT |
427 | { |
428 | struct ext3_inode_info *ei = EXT3_I(inode); | |
429 | __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data; | |
430 | __le32 *p; | |
43d23f90 MC |
431 | ext3_fsblk_t bg_start; |
432 | ext3_grpblk_t colour; | |
1da177e4 LT |
433 | |
434 | /* Try to find previous block */ | |
d6859bfc | 435 | for (p = ind->p - 1; p >= start; p--) { |
1da177e4 LT |
436 | if (*p) |
437 | return le32_to_cpu(*p); | |
d6859bfc | 438 | } |
1da177e4 LT |
439 | |
440 | /* No such thing, so let's try location of indirect block */ | |
441 | if (ind->bh) | |
442 | return ind->bh->b_blocknr; | |
443 | ||
444 | /* | |
d6859bfc AM |
445 | * It is going to be referred to from the inode itself? OK, just put it |
446 | * into the same cylinder group then. | |
1da177e4 | 447 | */ |
43d23f90 | 448 | bg_start = ext3_group_first_block_no(inode->i_sb, ei->i_block_group); |
1da177e4 LT |
449 | colour = (current->pid % 16) * |
450 | (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16); | |
451 | return bg_start + colour; | |
452 | } | |
453 | ||
454 | /** | |
1cc8dcf5 | 455 | * ext3_find_goal - find a preferred place for allocation. |
1da177e4 LT |
456 | * @inode: owner |
457 | * @block: block we want | |
1da177e4 | 458 | * @partial: pointer to the last triple within a chain |
1da177e4 | 459 | * |
1cc8dcf5 | 460 | * Normally this function find the preferred place for block allocation, |
fb01bfda | 461 | * returns it. |
1da177e4 LT |
462 | */ |
463 | ||
43d23f90 | 464 | static ext3_fsblk_t ext3_find_goal(struct inode *inode, long block, |
fb01bfda | 465 | Indirect *partial) |
1da177e4 | 466 | { |
d6859bfc AM |
467 | struct ext3_block_alloc_info *block_i; |
468 | ||
469 | block_i = EXT3_I(inode)->i_block_alloc_info; | |
1da177e4 LT |
470 | |
471 | /* | |
472 | * try the heuristic for sequential allocation, | |
473 | * failing that at least try to get decent locality. | |
474 | */ | |
475 | if (block_i && (block == block_i->last_alloc_logical_block + 1) | |
476 | && (block_i->last_alloc_physical_block != 0)) { | |
fe55c452 | 477 | return block_i->last_alloc_physical_block + 1; |
1da177e4 LT |
478 | } |
479 | ||
fe55c452 | 480 | return ext3_find_near(inode, partial); |
1da177e4 | 481 | } |
d6859bfc | 482 | |
b47b2478 MC |
483 | /** |
484 | * ext3_blks_to_allocate: Look up the block map and count the number | |
485 | * of direct blocks need to be allocated for the given branch. | |
486 | * | |
e9ad5620 | 487 | * @branch: chain of indirect blocks |
b47b2478 MC |
488 | * @k: number of blocks need for indirect blocks |
489 | * @blks: number of data blocks to be mapped. | |
490 | * @blocks_to_boundary: the offset in the indirect block | |
491 | * | |
492 | * return the total number of blocks to be allocate, including the | |
493 | * direct and indirect blocks. | |
494 | */ | |
d6859bfc | 495 | static int ext3_blks_to_allocate(Indirect *branch, int k, unsigned long blks, |
b47b2478 MC |
496 | int blocks_to_boundary) |
497 | { | |
498 | unsigned long count = 0; | |
499 | ||
500 | /* | |
501 | * Simple case, [t,d]Indirect block(s) has not allocated yet | |
502 | * then it's clear blocks on that path have not allocated | |
503 | */ | |
504 | if (k > 0) { | |
d6859bfc | 505 | /* right now we don't handle cross boundary allocation */ |
b47b2478 MC |
506 | if (blks < blocks_to_boundary + 1) |
507 | count += blks; | |
508 | else | |
509 | count += blocks_to_boundary + 1; | |
510 | return count; | |
511 | } | |
512 | ||
513 | count++; | |
514 | while (count < blks && count <= blocks_to_boundary && | |
515 | le32_to_cpu(*(branch[0].p + count)) == 0) { | |
516 | count++; | |
517 | } | |
518 | return count; | |
519 | } | |
520 | ||
521 | /** | |
522 | * ext3_alloc_blocks: multiple allocate blocks needed for a branch | |
523 | * @indirect_blks: the number of blocks need to allocate for indirect | |
524 | * blocks | |
525 | * | |
526 | * @new_blocks: on return it will store the new block numbers for | |
527 | * the indirect blocks(if needed) and the first direct block, | |
528 | * @blks: on return it will store the total number of allocated | |
529 | * direct blocks | |
530 | */ | |
531 | static int ext3_alloc_blocks(handle_t *handle, struct inode *inode, | |
43d23f90 MC |
532 | ext3_fsblk_t goal, int indirect_blks, int blks, |
533 | ext3_fsblk_t new_blocks[4], int *err) | |
b47b2478 MC |
534 | { |
535 | int target, i; | |
536 | unsigned long count = 0; | |
537 | int index = 0; | |
43d23f90 | 538 | ext3_fsblk_t current_block = 0; |
b47b2478 MC |
539 | int ret = 0; |
540 | ||
541 | /* | |
542 | * Here we try to allocate the requested multiple blocks at once, | |
543 | * on a best-effort basis. | |
544 | * To build a branch, we should allocate blocks for | |
545 | * the indirect blocks(if not allocated yet), and at least | |
546 | * the first direct block of this branch. That's the | |
547 | * minimum number of blocks need to allocate(required) | |
548 | */ | |
549 | target = blks + indirect_blks; | |
550 | ||
551 | while (1) { | |
552 | count = target; | |
553 | /* allocating blocks for indirect blocks and direct blocks */ | |
d6859bfc | 554 | current_block = ext3_new_blocks(handle,inode,goal,&count,err); |
b47b2478 MC |
555 | if (*err) |
556 | goto failed_out; | |
557 | ||
558 | target -= count; | |
559 | /* allocate blocks for indirect blocks */ | |
560 | while (index < indirect_blks && count) { | |
561 | new_blocks[index++] = current_block++; | |
562 | count--; | |
563 | } | |
564 | ||
565 | if (count > 0) | |
566 | break; | |
567 | } | |
568 | ||
569 | /* save the new block number for the first direct block */ | |
570 | new_blocks[index] = current_block; | |
571 | ||
572 | /* total number of blocks allocated for direct blocks */ | |
573 | ret = count; | |
574 | *err = 0; | |
575 | return ret; | |
576 | failed_out: | |
577 | for (i = 0; i <index; i++) | |
578 | ext3_free_blocks(handle, inode, new_blocks[i], 1); | |
579 | return ret; | |
580 | } | |
1da177e4 LT |
581 | |
582 | /** | |
583 | * ext3_alloc_branch - allocate and set up a chain of blocks. | |
584 | * @inode: owner | |
b47b2478 MC |
585 | * @indirect_blks: number of allocated indirect blocks |
586 | * @blks: number of allocated direct blocks | |
1da177e4 LT |
587 | * @offsets: offsets (in the blocks) to store the pointers to next. |
588 | * @branch: place to store the chain in. | |
589 | * | |
b47b2478 | 590 | * This function allocates blocks, zeroes out all but the last one, |
1da177e4 LT |
591 | * links them into chain and (if we are synchronous) writes them to disk. |
592 | * In other words, it prepares a branch that can be spliced onto the | |
593 | * inode. It stores the information about that chain in the branch[], in | |
594 | * the same format as ext3_get_branch() would do. We are calling it after | |
595 | * we had read the existing part of chain and partial points to the last | |
596 | * triple of that (one with zero ->key). Upon the exit we have the same | |
5b116879 | 597 | * picture as after the successful ext3_get_block(), except that in one |
1da177e4 LT |
598 | * place chain is disconnected - *branch->p is still zero (we did not |
599 | * set the last link), but branch->key contains the number that should | |
600 | * be placed into *branch->p to fill that gap. | |
601 | * | |
602 | * If allocation fails we free all blocks we've allocated (and forget | |
603 | * their buffer_heads) and return the error value the from failed | |
604 | * ext3_alloc_block() (normally -ENOSPC). Otherwise we set the chain | |
605 | * as described above and return 0. | |
606 | */ | |
1da177e4 | 607 | static int ext3_alloc_branch(handle_t *handle, struct inode *inode, |
43d23f90 | 608 | int indirect_blks, int *blks, ext3_fsblk_t goal, |
b47b2478 | 609 | int *offsets, Indirect *branch) |
1da177e4 LT |
610 | { |
611 | int blocksize = inode->i_sb->s_blocksize; | |
b47b2478 | 612 | int i, n = 0; |
1da177e4 | 613 | int err = 0; |
b47b2478 MC |
614 | struct buffer_head *bh; |
615 | int num; | |
43d23f90 MC |
616 | ext3_fsblk_t new_blocks[4]; |
617 | ext3_fsblk_t current_block; | |
1da177e4 | 618 | |
b47b2478 MC |
619 | num = ext3_alloc_blocks(handle, inode, goal, indirect_blks, |
620 | *blks, new_blocks, &err); | |
621 | if (err) | |
622 | return err; | |
1da177e4 | 623 | |
b47b2478 MC |
624 | branch[0].key = cpu_to_le32(new_blocks[0]); |
625 | /* | |
626 | * metadata blocks and data blocks are allocated. | |
627 | */ | |
628 | for (n = 1; n <= indirect_blks; n++) { | |
629 | /* | |
630 | * Get buffer_head for parent block, zero it out | |
631 | * and set the pointer to new one, then send | |
632 | * parent to disk. | |
633 | */ | |
634 | bh = sb_getblk(inode->i_sb, new_blocks[n-1]); | |
635 | branch[n].bh = bh; | |
636 | lock_buffer(bh); | |
637 | BUFFER_TRACE(bh, "call get_create_access"); | |
638 | err = ext3_journal_get_create_access(handle, bh); | |
639 | if (err) { | |
1da177e4 | 640 | unlock_buffer(bh); |
b47b2478 MC |
641 | brelse(bh); |
642 | goto failed; | |
643 | } | |
1da177e4 | 644 | |
b47b2478 MC |
645 | memset(bh->b_data, 0, blocksize); |
646 | branch[n].p = (__le32 *) bh->b_data + offsets[n]; | |
647 | branch[n].key = cpu_to_le32(new_blocks[n]); | |
648 | *branch[n].p = branch[n].key; | |
649 | if ( n == indirect_blks) { | |
650 | current_block = new_blocks[n]; | |
651 | /* | |
652 | * End of chain, update the last new metablock of | |
653 | * the chain to point to the new allocated | |
654 | * data blocks numbers | |
655 | */ | |
656 | for (i=1; i < num; i++) | |
657 | *(branch[n].p + i) = cpu_to_le32(++current_block); | |
1da177e4 | 658 | } |
b47b2478 MC |
659 | BUFFER_TRACE(bh, "marking uptodate"); |
660 | set_buffer_uptodate(bh); | |
661 | unlock_buffer(bh); | |
1da177e4 | 662 | |
b47b2478 MC |
663 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); |
664 | err = ext3_journal_dirty_metadata(handle, bh); | |
665 | if (err) | |
666 | goto failed; | |
667 | } | |
668 | *blks = num; | |
669 | return err; | |
670 | failed: | |
1da177e4 | 671 | /* Allocation failed, free what we already allocated */ |
b47b2478 | 672 | for (i = 1; i <= n ; i++) { |
1da177e4 LT |
673 | BUFFER_TRACE(branch[i].bh, "call journal_forget"); |
674 | ext3_journal_forget(handle, branch[i].bh); | |
675 | } | |
b47b2478 MC |
676 | for (i = 0; i <indirect_blks; i++) |
677 | ext3_free_blocks(handle, inode, new_blocks[i], 1); | |
678 | ||
679 | ext3_free_blocks(handle, inode, new_blocks[i], num); | |
680 | ||
1da177e4 LT |
681 | return err; |
682 | } | |
683 | ||
684 | /** | |
d6859bfc AM |
685 | * ext3_splice_branch - splice the allocated branch onto inode. |
686 | * @inode: owner | |
687 | * @block: (logical) number of block we are adding | |
688 | * @chain: chain of indirect blocks (with a missing link - see | |
689 | * ext3_alloc_branch) | |
690 | * @where: location of missing link | |
691 | * @num: number of indirect blocks we are adding | |
692 | * @blks: number of direct blocks we are adding | |
693 | * | |
694 | * This function fills the missing link and does all housekeeping needed in | |
695 | * inode (->i_blocks, etc.). In case of success we end up with the full | |
696 | * chain to new block and return 0. | |
1da177e4 | 697 | */ |
d6859bfc AM |
698 | static int ext3_splice_branch(handle_t *handle, struct inode *inode, |
699 | long block, Indirect *where, int num, int blks) | |
1da177e4 LT |
700 | { |
701 | int i; | |
702 | int err = 0; | |
d6859bfc | 703 | struct ext3_block_alloc_info *block_i; |
43d23f90 | 704 | ext3_fsblk_t current_block; |
fe8bc91c | 705 | struct ext3_inode_info *ei = EXT3_I(inode); |
d6859bfc | 706 | |
fe8bc91c | 707 | block_i = ei->i_block_alloc_info; |
1da177e4 LT |
708 | /* |
709 | * If we're splicing into a [td]indirect block (as opposed to the | |
710 | * inode) then we need to get write access to the [td]indirect block | |
711 | * before the splice. | |
712 | */ | |
713 | if (where->bh) { | |
714 | BUFFER_TRACE(where->bh, "get_write_access"); | |
715 | err = ext3_journal_get_write_access(handle, where->bh); | |
716 | if (err) | |
717 | goto err_out; | |
718 | } | |
1da177e4 LT |
719 | /* That's it */ |
720 | ||
721 | *where->p = where->key; | |
d6859bfc AM |
722 | |
723 | /* | |
724 | * Update the host buffer_head or inode to point to more just allocated | |
725 | * direct blocks blocks | |
726 | */ | |
b47b2478 | 727 | if (num == 0 && blks > 1) { |
5dea5176 | 728 | current_block = le32_to_cpu(where->key) + 1; |
b47b2478 MC |
729 | for (i = 1; i < blks; i++) |
730 | *(where->p + i ) = cpu_to_le32(current_block++); | |
731 | } | |
1da177e4 LT |
732 | |
733 | /* | |
734 | * update the most recently allocated logical & physical block | |
735 | * in i_block_alloc_info, to assist find the proper goal block for next | |
736 | * allocation | |
737 | */ | |
738 | if (block_i) { | |
b47b2478 | 739 | block_i->last_alloc_logical_block = block + blks - 1; |
d6859bfc | 740 | block_i->last_alloc_physical_block = |
5dea5176 | 741 | le32_to_cpu(where[num].key) + blks - 1; |
1da177e4 LT |
742 | } |
743 | ||
744 | /* We are done with atomic stuff, now do the rest of housekeeping */ | |
745 | ||
746 | inode->i_ctime = CURRENT_TIME_SEC; | |
747 | ext3_mark_inode_dirty(handle, inode); | |
fe8bc91c JK |
748 | /* ext3_mark_inode_dirty already updated i_sync_tid */ |
749 | atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid); | |
1da177e4 LT |
750 | |
751 | /* had we spliced it onto indirect block? */ | |
752 | if (where->bh) { | |
753 | /* | |
d6859bfc | 754 | * If we spliced it onto an indirect block, we haven't |
1da177e4 LT |
755 | * altered the inode. Note however that if it is being spliced |
756 | * onto an indirect block at the very end of the file (the | |
757 | * file is growing) then we *will* alter the inode to reflect | |
758 | * the new i_size. But that is not done here - it is done in | |
759 | * generic_commit_write->__mark_inode_dirty->ext3_dirty_inode. | |
760 | */ | |
761 | jbd_debug(5, "splicing indirect only\n"); | |
762 | BUFFER_TRACE(where->bh, "call ext3_journal_dirty_metadata"); | |
763 | err = ext3_journal_dirty_metadata(handle, where->bh); | |
ae6ddcc5 | 764 | if (err) |
1da177e4 LT |
765 | goto err_out; |
766 | } else { | |
767 | /* | |
768 | * OK, we spliced it into the inode itself on a direct block. | |
769 | * Inode was dirtied above. | |
770 | */ | |
771 | jbd_debug(5, "splicing direct\n"); | |
772 | } | |
773 | return err; | |
774 | ||
1da177e4 | 775 | err_out: |
b47b2478 | 776 | for (i = 1; i <= num; i++) { |
1da177e4 LT |
777 | BUFFER_TRACE(where[i].bh, "call journal_forget"); |
778 | ext3_journal_forget(handle, where[i].bh); | |
d6859bfc | 779 | ext3_free_blocks(handle,inode,le32_to_cpu(where[i-1].key),1); |
1da177e4 | 780 | } |
b47b2478 MC |
781 | ext3_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks); |
782 | ||
1da177e4 LT |
783 | return err; |
784 | } | |
785 | ||
786 | /* | |
787 | * Allocation strategy is simple: if we have to allocate something, we will | |
788 | * have to go the whole way to leaf. So let's do it before attaching anything | |
789 | * to tree, set linkage between the newborn blocks, write them if sync is | |
790 | * required, recheck the path, free and repeat if check fails, otherwise | |
791 | * set the last missing link (that will protect us from any truncate-generated | |
792 | * removals - all blocks on the path are immune now) and possibly force the | |
793 | * write on the parent block. | |
794 | * That has a nice additional property: no special recovery from the failed | |
795 | * allocations is needed - we simply release blocks and do not touch anything | |
796 | * reachable from inode. | |
797 | * | |
d6859bfc | 798 | * `handle' can be NULL if create == 0. |
1da177e4 LT |
799 | * |
800 | * The BKL may not be held on entry here. Be sure to take it early. | |
89747d36 MC |
801 | * return > 0, # of blocks mapped or allocated. |
802 | * return = 0, if plain lookup failed. | |
803 | * return < 0, error case. | |
1da177e4 | 804 | */ |
d6859bfc AM |
805 | int ext3_get_blocks_handle(handle_t *handle, struct inode *inode, |
806 | sector_t iblock, unsigned long maxblocks, | |
807 | struct buffer_head *bh_result, | |
43237b54 | 808 | int create) |
1da177e4 LT |
809 | { |
810 | int err = -EIO; | |
811 | int offsets[4]; | |
812 | Indirect chain[4]; | |
813 | Indirect *partial; | |
43d23f90 | 814 | ext3_fsblk_t goal; |
b47b2478 | 815 | int indirect_blks; |
89747d36 MC |
816 | int blocks_to_boundary = 0; |
817 | int depth; | |
1da177e4 | 818 | struct ext3_inode_info *ei = EXT3_I(inode); |
89747d36 | 819 | int count = 0; |
43d23f90 | 820 | ext3_fsblk_t first_block = 0; |
89747d36 | 821 | |
1da177e4 LT |
822 | |
823 | J_ASSERT(handle != NULL || create == 0); | |
d6859bfc | 824 | depth = ext3_block_to_path(inode,iblock,offsets,&blocks_to_boundary); |
1da177e4 LT |
825 | |
826 | if (depth == 0) | |
827 | goto out; | |
828 | ||
1da177e4 LT |
829 | partial = ext3_get_branch(inode, depth, offsets, chain, &err); |
830 | ||
831 | /* Simplest case - block found, no allocation needed */ | |
832 | if (!partial) { | |
5dea5176 | 833 | first_block = le32_to_cpu(chain[depth - 1].key); |
1da177e4 | 834 | clear_buffer_new(bh_result); |
89747d36 MC |
835 | count++; |
836 | /*map more blocks*/ | |
837 | while (count < maxblocks && count <= blocks_to_boundary) { | |
43d23f90 | 838 | ext3_fsblk_t blk; |
5dea5176 | 839 | |
e8ef7aae | 840 | if (!verify_chain(chain, chain + depth - 1)) { |
89747d36 MC |
841 | /* |
842 | * Indirect block might be removed by | |
843 | * truncate while we were reading it. | |
844 | * Handling of that case: forget what we've | |
845 | * got now. Flag the err as EAGAIN, so it | |
846 | * will reread. | |
847 | */ | |
848 | err = -EAGAIN; | |
849 | count = 0; | |
850 | break; | |
851 | } | |
5dea5176 MC |
852 | blk = le32_to_cpu(*(chain[depth-1].p + count)); |
853 | ||
854 | if (blk == first_block + count) | |
89747d36 MC |
855 | count++; |
856 | else | |
857 | break; | |
858 | } | |
859 | if (err != -EAGAIN) | |
860 | goto got_it; | |
1da177e4 LT |
861 | } |
862 | ||
863 | /* Next simple case - plain lookup or failed read of indirect block */ | |
fe55c452 MC |
864 | if (!create || err == -EIO) |
865 | goto cleanup; | |
866 | ||
97461518 | 867 | mutex_lock(&ei->truncate_mutex); |
fe55c452 MC |
868 | |
869 | /* | |
870 | * If the indirect block is missing while we are reading | |
871 | * the chain(ext3_get_branch() returns -EAGAIN err), or | |
872 | * if the chain has been changed after we grab the semaphore, | |
873 | * (either because another process truncated this branch, or | |
874 | * another get_block allocated this branch) re-grab the chain to see if | |
875 | * the request block has been allocated or not. | |
876 | * | |
877 | * Since we already block the truncate/other get_block | |
878 | * at this point, we will have the current copy of the chain when we | |
879 | * splice the branch into the tree. | |
880 | */ | |
881 | if (err == -EAGAIN || !verify_chain(chain, partial)) { | |
1da177e4 | 882 | while (partial > chain) { |
1da177e4 LT |
883 | brelse(partial->bh); |
884 | partial--; | |
885 | } | |
fe55c452 MC |
886 | partial = ext3_get_branch(inode, depth, offsets, chain, &err); |
887 | if (!partial) { | |
89747d36 | 888 | count++; |
97461518 | 889 | mutex_unlock(&ei->truncate_mutex); |
fe55c452 MC |
890 | if (err) |
891 | goto cleanup; | |
892 | clear_buffer_new(bh_result); | |
893 | goto got_it; | |
894 | } | |
1da177e4 LT |
895 | } |
896 | ||
897 | /* | |
fe55c452 MC |
898 | * Okay, we need to do block allocation. Lazily initialize the block |
899 | * allocation info here if necessary | |
900 | */ | |
901 | if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info)) | |
1da177e4 | 902 | ext3_init_block_alloc_info(inode); |
1da177e4 | 903 | |
fb01bfda | 904 | goal = ext3_find_goal(inode, iblock, partial); |
1da177e4 | 905 | |
b47b2478 MC |
906 | /* the number of blocks need to allocate for [d,t]indirect blocks */ |
907 | indirect_blks = (chain + depth) - partial - 1; | |
1da177e4 | 908 | |
b47b2478 MC |
909 | /* |
910 | * Next look up the indirect map to count the totoal number of | |
911 | * direct blocks to allocate for this branch. | |
912 | */ | |
913 | count = ext3_blks_to_allocate(partial, indirect_blks, | |
914 | maxblocks, blocks_to_boundary); | |
1da177e4 LT |
915 | /* |
916 | * Block out ext3_truncate while we alter the tree | |
917 | */ | |
b47b2478 | 918 | err = ext3_alloc_branch(handle, inode, indirect_blks, &count, goal, |
fe55c452 | 919 | offsets + (partial - chain), partial); |
1da177e4 | 920 | |
fe55c452 MC |
921 | /* |
922 | * The ext3_splice_branch call will free and forget any buffers | |
1da177e4 LT |
923 | * on the new chain if there is a failure, but that risks using |
924 | * up transaction credits, especially for bitmaps where the | |
925 | * credits cannot be returned. Can we handle this somehow? We | |
fe55c452 MC |
926 | * may need to return -EAGAIN upwards in the worst case. --sct |
927 | */ | |
1da177e4 | 928 | if (!err) |
b47b2478 MC |
929 | err = ext3_splice_branch(handle, inode, iblock, |
930 | partial, indirect_blks, count); | |
97461518 | 931 | mutex_unlock(&ei->truncate_mutex); |
1da177e4 LT |
932 | if (err) |
933 | goto cleanup; | |
934 | ||
935 | set_buffer_new(bh_result); | |
fe55c452 MC |
936 | got_it: |
937 | map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); | |
20acaa18 | 938 | if (count > blocks_to_boundary) |
fe55c452 | 939 | set_buffer_boundary(bh_result); |
89747d36 | 940 | err = count; |
fe55c452 MC |
941 | /* Clean up and exit */ |
942 | partial = chain + depth - 1; /* the whole chain */ | |
943 | cleanup: | |
1da177e4 | 944 | while (partial > chain) { |
fe55c452 | 945 | BUFFER_TRACE(partial->bh, "call brelse"); |
1da177e4 LT |
946 | brelse(partial->bh); |
947 | partial--; | |
948 | } | |
fe55c452 MC |
949 | BUFFER_TRACE(bh_result, "returned"); |
950 | out: | |
951 | return err; | |
1da177e4 LT |
952 | } |
953 | ||
bd1939de JK |
954 | /* Maximum number of blocks we map for direct IO at once. */ |
955 | #define DIO_MAX_BLOCKS 4096 | |
956 | /* | |
957 | * Number of credits we need for writing DIO_MAX_BLOCKS: | |
958 | * We need sb + group descriptor + bitmap + inode -> 4 | |
959 | * For B blocks with A block pointers per block we need: | |
960 | * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect). | |
961 | * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25. | |
962 | */ | |
963 | #define DIO_CREDITS 25 | |
1da177e4 | 964 | |
f91a2ad2 BP |
965 | static int ext3_get_block(struct inode *inode, sector_t iblock, |
966 | struct buffer_head *bh_result, int create) | |
1da177e4 | 967 | { |
3e4fdaf8 | 968 | handle_t *handle = ext3_journal_current_handle(); |
bd1939de | 969 | int ret = 0, started = 0; |
1d8fa7a2 | 970 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; |
1da177e4 | 971 | |
bd1939de JK |
972 | if (create && !handle) { /* Direct IO write... */ |
973 | if (max_blocks > DIO_MAX_BLOCKS) | |
974 | max_blocks = DIO_MAX_BLOCKS; | |
975 | handle = ext3_journal_start(inode, DIO_CREDITS + | |
c459001f | 976 | EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb)); |
bd1939de | 977 | if (IS_ERR(handle)) { |
1da177e4 | 978 | ret = PTR_ERR(handle); |
bd1939de | 979 | goto out; |
1da177e4 | 980 | } |
bd1939de | 981 | started = 1; |
1da177e4 LT |
982 | } |
983 | ||
bd1939de | 984 | ret = ext3_get_blocks_handle(handle, inode, iblock, |
43237b54 | 985 | max_blocks, bh_result, create); |
bd1939de JK |
986 | if (ret > 0) { |
987 | bh_result->b_size = (ret << inode->i_blkbits); | |
988 | ret = 0; | |
89747d36 | 989 | } |
bd1939de JK |
990 | if (started) |
991 | ext3_journal_stop(handle); | |
992 | out: | |
1da177e4 LT |
993 | return ret; |
994 | } | |
995 | ||
68c9d702 JB |
996 | int ext3_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, |
997 | u64 start, u64 len) | |
998 | { | |
999 | return generic_block_fiemap(inode, fieinfo, start, len, | |
1000 | ext3_get_block); | |
1001 | } | |
1002 | ||
1da177e4 LT |
1003 | /* |
1004 | * `handle' can be NULL if create is zero | |
1005 | */ | |
d6859bfc AM |
1006 | struct buffer_head *ext3_getblk(handle_t *handle, struct inode *inode, |
1007 | long block, int create, int *errp) | |
1da177e4 LT |
1008 | { |
1009 | struct buffer_head dummy; | |
1010 | int fatal = 0, err; | |
1011 | ||
1012 | J_ASSERT(handle != NULL || create == 0); | |
1013 | ||
1014 | dummy.b_state = 0; | |
1015 | dummy.b_blocknr = -1000; | |
1016 | buffer_trace_init(&dummy.b_history); | |
89747d36 | 1017 | err = ext3_get_blocks_handle(handle, inode, block, 1, |
43237b54 | 1018 | &dummy, create); |
3665d0e5 BP |
1019 | /* |
1020 | * ext3_get_blocks_handle() returns number of blocks | |
1021 | * mapped. 0 in case of a HOLE. | |
1022 | */ | |
1023 | if (err > 0) { | |
1024 | if (err > 1) | |
1025 | WARN_ON(1); | |
89747d36 | 1026 | err = 0; |
89747d36 MC |
1027 | } |
1028 | *errp = err; | |
1029 | if (!err && buffer_mapped(&dummy)) { | |
1da177e4 LT |
1030 | struct buffer_head *bh; |
1031 | bh = sb_getblk(inode->i_sb, dummy.b_blocknr); | |
2973dfdb GOC |
1032 | if (!bh) { |
1033 | *errp = -EIO; | |
1034 | goto err; | |
1035 | } | |
1da177e4 LT |
1036 | if (buffer_new(&dummy)) { |
1037 | J_ASSERT(create != 0); | |
c80544dc | 1038 | J_ASSERT(handle != NULL); |
1da177e4 | 1039 | |
d6859bfc AM |
1040 | /* |
1041 | * Now that we do not always journal data, we should | |
1042 | * keep in mind whether this should always journal the | |
1043 | * new buffer as metadata. For now, regular file | |
1044 | * writes use ext3_get_block instead, so it's not a | |
1045 | * problem. | |
1046 | */ | |
1da177e4 LT |
1047 | lock_buffer(bh); |
1048 | BUFFER_TRACE(bh, "call get_create_access"); | |
1049 | fatal = ext3_journal_get_create_access(handle, bh); | |
1050 | if (!fatal && !buffer_uptodate(bh)) { | |
d6859bfc | 1051 | memset(bh->b_data,0,inode->i_sb->s_blocksize); |
1da177e4 LT |
1052 | set_buffer_uptodate(bh); |
1053 | } | |
1054 | unlock_buffer(bh); | |
1055 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
1056 | err = ext3_journal_dirty_metadata(handle, bh); | |
1057 | if (!fatal) | |
1058 | fatal = err; | |
1059 | } else { | |
1060 | BUFFER_TRACE(bh, "not a new buffer"); | |
1061 | } | |
1062 | if (fatal) { | |
1063 | *errp = fatal; | |
1064 | brelse(bh); | |
1065 | bh = NULL; | |
1066 | } | |
1067 | return bh; | |
1068 | } | |
2973dfdb | 1069 | err: |
1da177e4 LT |
1070 | return NULL; |
1071 | } | |
1072 | ||
d6859bfc | 1073 | struct buffer_head *ext3_bread(handle_t *handle, struct inode *inode, |
1da177e4 LT |
1074 | int block, int create, int *err) |
1075 | { | |
1076 | struct buffer_head * bh; | |
1077 | ||
1078 | bh = ext3_getblk(handle, inode, block, create, err); | |
1079 | if (!bh) | |
1080 | return bh; | |
1081 | if (buffer_uptodate(bh)) | |
1082 | return bh; | |
caa38fb0 | 1083 | ll_rw_block(READ_META, 1, &bh); |
1da177e4 LT |
1084 | wait_on_buffer(bh); |
1085 | if (buffer_uptodate(bh)) | |
1086 | return bh; | |
1087 | put_bh(bh); | |
1088 | *err = -EIO; | |
1089 | return NULL; | |
1090 | } | |
1091 | ||
1092 | static int walk_page_buffers( handle_t *handle, | |
1093 | struct buffer_head *head, | |
1094 | unsigned from, | |
1095 | unsigned to, | |
1096 | int *partial, | |
1097 | int (*fn)( handle_t *handle, | |
1098 | struct buffer_head *bh)) | |
1099 | { | |
1100 | struct buffer_head *bh; | |
1101 | unsigned block_start, block_end; | |
1102 | unsigned blocksize = head->b_size; | |
1103 | int err, ret = 0; | |
1104 | struct buffer_head *next; | |
1105 | ||
1106 | for ( bh = head, block_start = 0; | |
1107 | ret == 0 && (bh != head || !block_start); | |
e9ad5620 | 1108 | block_start = block_end, bh = next) |
1da177e4 LT |
1109 | { |
1110 | next = bh->b_this_page; | |
1111 | block_end = block_start + blocksize; | |
1112 | if (block_end <= from || block_start >= to) { | |
1113 | if (partial && !buffer_uptodate(bh)) | |
1114 | *partial = 1; | |
1115 | continue; | |
1116 | } | |
1117 | err = (*fn)(handle, bh); | |
1118 | if (!ret) | |
1119 | ret = err; | |
1120 | } | |
1121 | return ret; | |
1122 | } | |
1123 | ||
1124 | /* | |
1125 | * To preserve ordering, it is essential that the hole instantiation and | |
1126 | * the data write be encapsulated in a single transaction. We cannot | |
1127 | * close off a transaction and start a new one between the ext3_get_block() | |
1128 | * and the commit_write(). So doing the journal_start at the start of | |
1129 | * prepare_write() is the right place. | |
1130 | * | |
1131 | * Also, this function can nest inside ext3_writepage() -> | |
1132 | * block_write_full_page(). In that case, we *know* that ext3_writepage() | |
1133 | * has generated enough buffer credits to do the whole page. So we won't | |
1134 | * block on the journal in that case, which is good, because the caller may | |
1135 | * be PF_MEMALLOC. | |
1136 | * | |
1137 | * By accident, ext3 can be reentered when a transaction is open via | |
1138 | * quota file writes. If we were to commit the transaction while thus | |
1139 | * reentered, there can be a deadlock - we would be holding a quota | |
1140 | * lock, and the commit would never complete if another thread had a | |
1141 | * transaction open and was blocking on the quota lock - a ranking | |
1142 | * violation. | |
1143 | * | |
1144 | * So what we do is to rely on the fact that journal_stop/journal_start | |
1145 | * will _not_ run commit under these circumstances because handle->h_ref | |
1146 | * is elevated. We'll still have enough credits for the tiny quotafile | |
ae6ddcc5 | 1147 | * write. |
1da177e4 | 1148 | */ |
d6859bfc AM |
1149 | static int do_journal_get_write_access(handle_t *handle, |
1150 | struct buffer_head *bh) | |
1da177e4 LT |
1151 | { |
1152 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1153 | return 0; | |
1154 | return ext3_journal_get_write_access(handle, bh); | |
1155 | } | |
1156 | ||
68eb3db0 JK |
1157 | /* |
1158 | * Truncate blocks that were not used by write. We have to truncate the | |
1159 | * pagecache as well so that corresponding buffers get properly unmapped. | |
1160 | */ | |
1161 | static void ext3_truncate_failed_write(struct inode *inode) | |
1162 | { | |
1163 | truncate_inode_pages(inode->i_mapping, inode->i_size); | |
1164 | ext3_truncate(inode); | |
1165 | } | |
1166 | ||
f4fc66a8 NP |
1167 | static int ext3_write_begin(struct file *file, struct address_space *mapping, |
1168 | loff_t pos, unsigned len, unsigned flags, | |
1169 | struct page **pagep, void **fsdata) | |
1da177e4 | 1170 | { |
f4fc66a8 | 1171 | struct inode *inode = mapping->host; |
695f6ae0 | 1172 | int ret; |
1da177e4 LT |
1173 | handle_t *handle; |
1174 | int retries = 0; | |
f4fc66a8 NP |
1175 | struct page *page; |
1176 | pgoff_t index; | |
1177 | unsigned from, to; | |
695f6ae0 JK |
1178 | /* Reserve one block more for addition to orphan list in case |
1179 | * we allocate blocks but write fails for some reason */ | |
1180 | int needed_blocks = ext3_writepage_trans_blocks(inode) + 1; | |
f4fc66a8 NP |
1181 | |
1182 | index = pos >> PAGE_CACHE_SHIFT; | |
1183 | from = pos & (PAGE_CACHE_SIZE - 1); | |
1184 | to = from + len; | |
1da177e4 LT |
1185 | |
1186 | retry: | |
54566b2c | 1187 | page = grab_cache_page_write_begin(mapping, index, flags); |
f4fc66a8 NP |
1188 | if (!page) |
1189 | return -ENOMEM; | |
1190 | *pagep = page; | |
1191 | ||
1da177e4 | 1192 | handle = ext3_journal_start(inode, needed_blocks); |
1aa9b4b9 | 1193 | if (IS_ERR(handle)) { |
f4fc66a8 NP |
1194 | unlock_page(page); |
1195 | page_cache_release(page); | |
1aa9b4b9 AM |
1196 | ret = PTR_ERR(handle); |
1197 | goto out; | |
1198 | } | |
6e1db88d | 1199 | ret = __block_write_begin(page, pos, len, ext3_get_block); |
1da177e4 | 1200 | if (ret) |
f4fc66a8 | 1201 | goto write_begin_failed; |
1da177e4 LT |
1202 | |
1203 | if (ext3_should_journal_data(inode)) { | |
1204 | ret = walk_page_buffers(handle, page_buffers(page), | |
1205 | from, to, NULL, do_journal_get_write_access); | |
1206 | } | |
f4fc66a8 NP |
1207 | write_begin_failed: |
1208 | if (ret) { | |
5ec8b75e AK |
1209 | /* |
1210 | * block_write_begin may have instantiated a few blocks | |
1211 | * outside i_size. Trim these off again. Don't need | |
1212 | * i_size_read because we hold i_mutex. | |
695f6ae0 JK |
1213 | * |
1214 | * Add inode to orphan list in case we crash before truncate | |
9eaaa2d5 JK |
1215 | * finishes. Do this only if ext3_can_truncate() agrees so |
1216 | * that orphan processing code is happy. | |
5ec8b75e | 1217 | */ |
9eaaa2d5 | 1218 | if (pos + len > inode->i_size && ext3_can_truncate(inode)) |
695f6ae0 JK |
1219 | ext3_orphan_add(handle, inode); |
1220 | ext3_journal_stop(handle); | |
1221 | unlock_page(page); | |
1222 | page_cache_release(page); | |
5ec8b75e | 1223 | if (pos + len > inode->i_size) |
68eb3db0 | 1224 | ext3_truncate_failed_write(inode); |
f4fc66a8 | 1225 | } |
1da177e4 LT |
1226 | if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries)) |
1227 | goto retry; | |
1aa9b4b9 | 1228 | out: |
1da177e4 LT |
1229 | return ret; |
1230 | } | |
1231 | ||
f4fc66a8 | 1232 | |
d6859bfc | 1233 | int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh) |
1da177e4 LT |
1234 | { |
1235 | int err = journal_dirty_data(handle, bh); | |
1236 | if (err) | |
e05b6b52 | 1237 | ext3_journal_abort_handle(__func__, __func__, |
f4fc66a8 | 1238 | bh, handle, err); |
1da177e4 LT |
1239 | return err; |
1240 | } | |
1241 | ||
695f6ae0 JK |
1242 | /* For ordered writepage and write_end functions */ |
1243 | static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh) | |
1244 | { | |
1245 | /* | |
1246 | * Write could have mapped the buffer but it didn't copy the data in | |
1247 | * yet. So avoid filing such buffer into a transaction. | |
1248 | */ | |
1249 | if (buffer_mapped(bh) && buffer_uptodate(bh)) | |
1250 | return ext3_journal_dirty_data(handle, bh); | |
1251 | return 0; | |
1252 | } | |
1253 | ||
f4fc66a8 NP |
1254 | /* For write_end() in data=journal mode */ |
1255 | static int write_end_fn(handle_t *handle, struct buffer_head *bh) | |
1da177e4 LT |
1256 | { |
1257 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1258 | return 0; | |
1259 | set_buffer_uptodate(bh); | |
1260 | return ext3_journal_dirty_metadata(handle, bh); | |
1261 | } | |
1262 | ||
f4fc66a8 | 1263 | /* |
695f6ae0 JK |
1264 | * This is nasty and subtle: ext3_write_begin() could have allocated blocks |
1265 | * for the whole page but later we failed to copy the data in. Update inode | |
1266 | * size according to what we managed to copy. The rest is going to be | |
1267 | * truncated in write_end function. | |
f4fc66a8 | 1268 | */ |
695f6ae0 | 1269 | static void update_file_sizes(struct inode *inode, loff_t pos, unsigned copied) |
f4fc66a8 | 1270 | { |
695f6ae0 JK |
1271 | /* What matters to us is i_disksize. We don't write i_size anywhere */ |
1272 | if (pos + copied > inode->i_size) | |
1273 | i_size_write(inode, pos + copied); | |
1274 | if (pos + copied > EXT3_I(inode)->i_disksize) { | |
1275 | EXT3_I(inode)->i_disksize = pos + copied; | |
f4fc66a8 NP |
1276 | mark_inode_dirty(inode); |
1277 | } | |
f4fc66a8 NP |
1278 | } |
1279 | ||
1da177e4 LT |
1280 | /* |
1281 | * We need to pick up the new inode size which generic_commit_write gave us | |
1282 | * `file' can be NULL - eg, when called from page_symlink(). | |
1283 | * | |
1284 | * ext3 never places buffers on inode->i_mapping->private_list. metadata | |
1285 | * buffers are managed internally. | |
1286 | */ | |
f4fc66a8 NP |
1287 | static int ext3_ordered_write_end(struct file *file, |
1288 | struct address_space *mapping, | |
1289 | loff_t pos, unsigned len, unsigned copied, | |
1290 | struct page *page, void *fsdata) | |
1da177e4 LT |
1291 | { |
1292 | handle_t *handle = ext3_journal_current_handle(); | |
f4fc66a8 NP |
1293 | struct inode *inode = file->f_mapping->host; |
1294 | unsigned from, to; | |
1da177e4 LT |
1295 | int ret = 0, ret2; |
1296 | ||
695f6ae0 | 1297 | copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); |
f4fc66a8 | 1298 | |
695f6ae0 JK |
1299 | from = pos & (PAGE_CACHE_SIZE - 1); |
1300 | to = from + copied; | |
1da177e4 | 1301 | ret = walk_page_buffers(handle, page_buffers(page), |
695f6ae0 | 1302 | from, to, NULL, journal_dirty_data_fn); |
1da177e4 | 1303 | |
695f6ae0 JK |
1304 | if (ret == 0) |
1305 | update_file_sizes(inode, pos, copied); | |
1306 | /* | |
1307 | * There may be allocated blocks outside of i_size because | |
1308 | * we failed to copy some data. Prepare for truncate. | |
1309 | */ | |
9eaaa2d5 | 1310 | if (pos + len > inode->i_size && ext3_can_truncate(inode)) |
695f6ae0 | 1311 | ext3_orphan_add(handle, inode); |
1da177e4 LT |
1312 | ret2 = ext3_journal_stop(handle); |
1313 | if (!ret) | |
1314 | ret = ret2; | |
f4fc66a8 NP |
1315 | unlock_page(page); |
1316 | page_cache_release(page); | |
1317 | ||
695f6ae0 | 1318 | if (pos + len > inode->i_size) |
68eb3db0 | 1319 | ext3_truncate_failed_write(inode); |
f4fc66a8 | 1320 | return ret ? ret : copied; |
1da177e4 LT |
1321 | } |
1322 | ||
f4fc66a8 NP |
1323 | static int ext3_writeback_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 = file->f_mapping->host; |
695f6ae0 | 1330 | int ret; |
1da177e4 | 1331 | |
695f6ae0 JK |
1332 | copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); |
1333 | update_file_sizes(inode, pos, copied); | |
1334 | /* | |
1335 | * There may be allocated blocks outside of i_size because | |
1336 | * we failed to copy some data. Prepare for truncate. | |
1337 | */ | |
9eaaa2d5 | 1338 | if (pos + len > inode->i_size && ext3_can_truncate(inode)) |
695f6ae0 JK |
1339 | ext3_orphan_add(handle, inode); |
1340 | ret = ext3_journal_stop(handle); | |
f4fc66a8 NP |
1341 | unlock_page(page); |
1342 | page_cache_release(page); | |
1343 | ||
695f6ae0 | 1344 | if (pos + len > inode->i_size) |
68eb3db0 | 1345 | ext3_truncate_failed_write(inode); |
f4fc66a8 | 1346 | return ret ? ret : copied; |
1da177e4 LT |
1347 | } |
1348 | ||
f4fc66a8 NP |
1349 | static int ext3_journalled_write_end(struct file *file, |
1350 | struct address_space *mapping, | |
1351 | loff_t pos, unsigned len, unsigned copied, | |
1352 | struct page *page, void *fsdata) | |
1da177e4 LT |
1353 | { |
1354 | handle_t *handle = ext3_journal_current_handle(); | |
f4fc66a8 | 1355 | struct inode *inode = mapping->host; |
1da177e4 LT |
1356 | int ret = 0, ret2; |
1357 | int partial = 0; | |
f4fc66a8 | 1358 | unsigned from, to; |
1da177e4 | 1359 | |
f4fc66a8 NP |
1360 | from = pos & (PAGE_CACHE_SIZE - 1); |
1361 | to = from + len; | |
1362 | ||
1363 | if (copied < len) { | |
1364 | if (!PageUptodate(page)) | |
1365 | copied = 0; | |
695f6ae0 JK |
1366 | page_zero_new_buffers(page, from + copied, to); |
1367 | to = from + copied; | |
f4fc66a8 | 1368 | } |
1da177e4 LT |
1369 | |
1370 | ret = walk_page_buffers(handle, page_buffers(page), from, | |
f4fc66a8 | 1371 | to, &partial, write_end_fn); |
1da177e4 LT |
1372 | if (!partial) |
1373 | SetPageUptodate(page); | |
695f6ae0 JK |
1374 | |
1375 | if (pos + copied > inode->i_size) | |
1376 | i_size_write(inode, pos + copied); | |
1377 | /* | |
1378 | * There may be allocated blocks outside of i_size because | |
1379 | * we failed to copy some data. Prepare for truncate. | |
1380 | */ | |
9eaaa2d5 | 1381 | if (pos + len > inode->i_size && ext3_can_truncate(inode)) |
695f6ae0 | 1382 | ext3_orphan_add(handle, inode); |
9df93939 | 1383 | ext3_set_inode_state(inode, EXT3_STATE_JDATA); |
1da177e4 LT |
1384 | if (inode->i_size > EXT3_I(inode)->i_disksize) { |
1385 | EXT3_I(inode)->i_disksize = inode->i_size; | |
1386 | ret2 = ext3_mark_inode_dirty(handle, inode); | |
ae6ddcc5 | 1387 | if (!ret) |
1da177e4 LT |
1388 | ret = ret2; |
1389 | } | |
f4fc66a8 | 1390 | |
1da177e4 LT |
1391 | ret2 = ext3_journal_stop(handle); |
1392 | if (!ret) | |
1393 | ret = ret2; | |
f4fc66a8 NP |
1394 | unlock_page(page); |
1395 | page_cache_release(page); | |
1396 | ||
695f6ae0 | 1397 | if (pos + len > inode->i_size) |
68eb3db0 | 1398 | ext3_truncate_failed_write(inode); |
f4fc66a8 | 1399 | return ret ? ret : copied; |
1da177e4 LT |
1400 | } |
1401 | ||
ae6ddcc5 | 1402 | /* |
1da177e4 LT |
1403 | * bmap() is special. It gets used by applications such as lilo and by |
1404 | * the swapper to find the on-disk block of a specific piece of data. | |
1405 | * | |
1406 | * Naturally, this is dangerous if the block concerned is still in the | |
1407 | * journal. If somebody makes a swapfile on an ext3 data-journaling | |
1408 | * filesystem and enables swap, then they may get a nasty shock when the | |
1409 | * data getting swapped to that swapfile suddenly gets overwritten by | |
1410 | * the original zero's written out previously to the journal and | |
ae6ddcc5 | 1411 | * awaiting writeback in the kernel's buffer cache. |
1da177e4 LT |
1412 | * |
1413 | * So, if we see any bmap calls here on a modified, data-journaled file, | |
ae6ddcc5 | 1414 | * take extra steps to flush any blocks which might be in the cache. |
1da177e4 LT |
1415 | */ |
1416 | static sector_t ext3_bmap(struct address_space *mapping, sector_t block) | |
1417 | { | |
1418 | struct inode *inode = mapping->host; | |
1419 | journal_t *journal; | |
1420 | int err; | |
1421 | ||
9df93939 | 1422 | if (ext3_test_inode_state(inode, EXT3_STATE_JDATA)) { |
ae6ddcc5 | 1423 | /* |
1da177e4 LT |
1424 | * This is a REALLY heavyweight approach, but the use of |
1425 | * bmap on dirty files is expected to be extremely rare: | |
1426 | * only if we run lilo or swapon on a freshly made file | |
ae6ddcc5 | 1427 | * do we expect this to happen. |
1da177e4 LT |
1428 | * |
1429 | * (bmap requires CAP_SYS_RAWIO so this does not | |
1430 | * represent an unprivileged user DOS attack --- we'd be | |
1431 | * in trouble if mortal users could trigger this path at | |
ae6ddcc5 | 1432 | * will.) |
1da177e4 LT |
1433 | * |
1434 | * NB. EXT3_STATE_JDATA is not set on files other than | |
1435 | * regular files. If somebody wants to bmap a directory | |
1436 | * or symlink and gets confused because the buffer | |
1437 | * hasn't yet been flushed to disk, they deserve | |
1438 | * everything they get. | |
1439 | */ | |
1440 | ||
9df93939 | 1441 | ext3_clear_inode_state(inode, EXT3_STATE_JDATA); |
1da177e4 LT |
1442 | journal = EXT3_JOURNAL(inode); |
1443 | journal_lock_updates(journal); | |
1444 | err = journal_flush(journal); | |
1445 | journal_unlock_updates(journal); | |
1446 | ||
1447 | if (err) | |
1448 | return 0; | |
1449 | } | |
1450 | ||
1451 | return generic_block_bmap(mapping,block,ext3_get_block); | |
1452 | } | |
1453 | ||
1454 | static int bget_one(handle_t *handle, struct buffer_head *bh) | |
1455 | { | |
1456 | get_bh(bh); | |
1457 | return 0; | |
1458 | } | |
1459 | ||
1460 | static int bput_one(handle_t *handle, struct buffer_head *bh) | |
1461 | { | |
1462 | put_bh(bh); | |
1463 | return 0; | |
1464 | } | |
1465 | ||
9e80d407 JK |
1466 | static int buffer_unmapped(handle_t *handle, struct buffer_head *bh) |
1467 | { | |
1468 | return !buffer_mapped(bh); | |
1469 | } | |
695f6ae0 | 1470 | |
1da177e4 LT |
1471 | /* |
1472 | * Note that we always start a transaction even if we're not journalling | |
1473 | * data. This is to preserve ordering: any hole instantiation within | |
1474 | * __block_write_full_page -> ext3_get_block() should be journalled | |
1475 | * along with the data so we don't crash and then get metadata which | |
1476 | * refers to old data. | |
1477 | * | |
1478 | * In all journalling modes block_write_full_page() will start the I/O. | |
1479 | * | |
1480 | * Problem: | |
1481 | * | |
1482 | * ext3_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() -> | |
1483 | * ext3_writepage() | |
1484 | * | |
1485 | * Similar for: | |
1486 | * | |
1487 | * ext3_file_write() -> generic_file_write() -> __alloc_pages() -> ... | |
1488 | * | |
1489 | * Same applies to ext3_get_block(). We will deadlock on various things like | |
97461518 | 1490 | * lock_journal and i_truncate_mutex. |
1da177e4 LT |
1491 | * |
1492 | * Setting PF_MEMALLOC here doesn't work - too many internal memory | |
1493 | * allocations fail. | |
1494 | * | |
1495 | * 16May01: If we're reentered then journal_current_handle() will be | |
1496 | * non-zero. We simply *return*. | |
1497 | * | |
1498 | * 1 July 2001: @@@ FIXME: | |
1499 | * In journalled data mode, a data buffer may be metadata against the | |
1500 | * current transaction. But the same file is part of a shared mapping | |
1501 | * and someone does a writepage() on it. | |
1502 | * | |
1503 | * We will move the buffer onto the async_data list, but *after* it has | |
1504 | * been dirtied. So there's a small window where we have dirty data on | |
1505 | * BJ_Metadata. | |
1506 | * | |
1507 | * Note that this only applies to the last partial page in the file. The | |
1508 | * bit which block_write_full_page() uses prepare/commit for. (That's | |
1509 | * broken code anyway: it's wrong for msync()). | |
1510 | * | |
1511 | * It's a rare case: affects the final partial page, for journalled data | |
1512 | * where the file is subject to bith write() and writepage() in the same | |
1513 | * transction. To fix it we'll need a custom block_write_full_page(). | |
1514 | * We'll probably need that anyway for journalling writepage() output. | |
1515 | * | |
1516 | * We don't honour synchronous mounts for writepage(). That would be | |
1517 | * disastrous. Any write() or metadata operation will sync the fs for | |
1518 | * us. | |
1519 | * | |
1520 | * AKPM2: if all the page's buffers are mapped to disk and !data=journal, | |
1521 | * we don't need to open a transaction here. | |
1522 | */ | |
1523 | static int ext3_ordered_writepage(struct page *page, | |
d6859bfc | 1524 | struct writeback_control *wbc) |
1da177e4 LT |
1525 | { |
1526 | struct inode *inode = page->mapping->host; | |
1527 | struct buffer_head *page_bufs; | |
1528 | handle_t *handle = NULL; | |
1529 | int ret = 0; | |
1530 | int err; | |
1531 | ||
1532 | J_ASSERT(PageLocked(page)); | |
49792c80 | 1533 | WARN_ON_ONCE(IS_RDONLY(inode)); |
1da177e4 LT |
1534 | |
1535 | /* | |
1536 | * We give up here if we're reentered, because it might be for a | |
1537 | * different filesystem. | |
1538 | */ | |
1539 | if (ext3_journal_current_handle()) | |
1540 | goto out_fail; | |
1541 | ||
9e80d407 JK |
1542 | if (!page_has_buffers(page)) { |
1543 | create_empty_buffers(page, inode->i_sb->s_blocksize, | |
1544 | (1 << BH_Dirty)|(1 << BH_Uptodate)); | |
430db323 JK |
1545 | page_bufs = page_buffers(page); |
1546 | } else { | |
1547 | page_bufs = page_buffers(page); | |
1548 | if (!walk_page_buffers(NULL, page_bufs, 0, PAGE_CACHE_SIZE, | |
1549 | NULL, buffer_unmapped)) { | |
1550 | /* Provide NULL get_block() to catch bugs if buffers | |
1551 | * weren't really mapped */ | |
1552 | return block_write_full_page(page, NULL, wbc); | |
1553 | } | |
9e80d407 | 1554 | } |
1da177e4 LT |
1555 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); |
1556 | ||
1557 | if (IS_ERR(handle)) { | |
1558 | ret = PTR_ERR(handle); | |
1559 | goto out_fail; | |
1560 | } | |
1561 | ||
1da177e4 LT |
1562 | walk_page_buffers(handle, page_bufs, 0, |
1563 | PAGE_CACHE_SIZE, NULL, bget_one); | |
1564 | ||
1565 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1566 | ||
1567 | /* | |
1568 | * The page can become unlocked at any point now, and | |
1569 | * truncate can then come in and change things. So we | |
1570 | * can't touch *page from now on. But *page_bufs is | |
1571 | * safe due to elevated refcount. | |
1572 | */ | |
1573 | ||
1574 | /* | |
ae6ddcc5 | 1575 | * And attach them to the current transaction. But only if |
1da177e4 LT |
1576 | * block_write_full_page() succeeded. Otherwise they are unmapped, |
1577 | * and generally junk. | |
1578 | */ | |
1579 | if (ret == 0) { | |
1580 | err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE, | |
1581 | NULL, journal_dirty_data_fn); | |
1582 | if (!ret) | |
1583 | ret = err; | |
1584 | } | |
1585 | walk_page_buffers(handle, page_bufs, 0, | |
1586 | PAGE_CACHE_SIZE, NULL, bput_one); | |
1587 | err = ext3_journal_stop(handle); | |
1588 | if (!ret) | |
1589 | ret = err; | |
1590 | return ret; | |
1591 | ||
1592 | out_fail: | |
1593 | redirty_page_for_writepage(wbc, page); | |
1594 | unlock_page(page); | |
1595 | return ret; | |
1596 | } | |
1597 | ||
1da177e4 LT |
1598 | static int ext3_writeback_writepage(struct page *page, |
1599 | struct writeback_control *wbc) | |
1600 | { | |
1601 | struct inode *inode = page->mapping->host; | |
1602 | handle_t *handle = NULL; | |
1603 | int ret = 0; | |
1604 | int err; | |
1605 | ||
49792c80 DM |
1606 | J_ASSERT(PageLocked(page)); |
1607 | WARN_ON_ONCE(IS_RDONLY(inode)); | |
1608 | ||
1da177e4 LT |
1609 | if (ext3_journal_current_handle()) |
1610 | goto out_fail; | |
1611 | ||
430db323 JK |
1612 | if (page_has_buffers(page)) { |
1613 | if (!walk_page_buffers(NULL, page_buffers(page), 0, | |
1614 | PAGE_CACHE_SIZE, NULL, buffer_unmapped)) { | |
1615 | /* Provide NULL get_block() to catch bugs if buffers | |
1616 | * weren't really mapped */ | |
1617 | return block_write_full_page(page, NULL, wbc); | |
1618 | } | |
1619 | } | |
1620 | ||
1da177e4 LT |
1621 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); |
1622 | if (IS_ERR(handle)) { | |
1623 | ret = PTR_ERR(handle); | |
1624 | goto out_fail; | |
1625 | } | |
1626 | ||
0e31f51d | 1627 | if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode)) |
1da177e4 LT |
1628 | ret = nobh_writepage(page, ext3_get_block, wbc); |
1629 | else | |
1630 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1631 | ||
1632 | err = ext3_journal_stop(handle); | |
1633 | if (!ret) | |
1634 | ret = err; | |
1635 | return ret; | |
1636 | ||
1637 | out_fail: | |
1638 | redirty_page_for_writepage(wbc, page); | |
1639 | unlock_page(page); | |
1640 | return ret; | |
1641 | } | |
1642 | ||
1643 | static int ext3_journalled_writepage(struct page *page, | |
1644 | struct writeback_control *wbc) | |
1645 | { | |
1646 | struct inode *inode = page->mapping->host; | |
1647 | handle_t *handle = NULL; | |
1648 | int ret = 0; | |
1649 | int err; | |
1650 | ||
49792c80 DM |
1651 | J_ASSERT(PageLocked(page)); |
1652 | WARN_ON_ONCE(IS_RDONLY(inode)); | |
1653 | ||
1da177e4 LT |
1654 | if (ext3_journal_current_handle()) |
1655 | goto no_write; | |
1656 | ||
1657 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); | |
1658 | if (IS_ERR(handle)) { | |
1659 | ret = PTR_ERR(handle); | |
1660 | goto no_write; | |
1661 | } | |
1662 | ||
1663 | if (!page_has_buffers(page) || PageChecked(page)) { | |
1664 | /* | |
1665 | * It's mmapped pagecache. Add buffers and journal it. There | |
1666 | * doesn't seem much point in redirtying the page here. | |
1667 | */ | |
1668 | ClearPageChecked(page); | |
1669 | ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, | |
1670 | ext3_get_block); | |
ab4eb43c DL |
1671 | if (ret != 0) { |
1672 | ext3_journal_stop(handle); | |
1da177e4 | 1673 | goto out_unlock; |
ab4eb43c | 1674 | } |
1da177e4 LT |
1675 | ret = walk_page_buffers(handle, page_buffers(page), 0, |
1676 | PAGE_CACHE_SIZE, NULL, do_journal_get_write_access); | |
1677 | ||
1678 | err = walk_page_buffers(handle, page_buffers(page), 0, | |
f4fc66a8 | 1679 | PAGE_CACHE_SIZE, NULL, write_end_fn); |
1da177e4 LT |
1680 | if (ret == 0) |
1681 | ret = err; | |
9df93939 | 1682 | ext3_set_inode_state(inode, EXT3_STATE_JDATA); |
1da177e4 LT |
1683 | unlock_page(page); |
1684 | } else { | |
1685 | /* | |
1686 | * It may be a page full of checkpoint-mode buffers. We don't | |
1687 | * really know unless we go poke around in the buffer_heads. | |
1688 | * But block_write_full_page will do the right thing. | |
1689 | */ | |
1690 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1691 | } | |
1692 | err = ext3_journal_stop(handle); | |
1693 | if (!ret) | |
1694 | ret = err; | |
1695 | out: | |
1696 | return ret; | |
1697 | ||
1698 | no_write: | |
1699 | redirty_page_for_writepage(wbc, page); | |
1700 | out_unlock: | |
1701 | unlock_page(page); | |
1702 | goto out; | |
1703 | } | |
1704 | ||
1705 | static int ext3_readpage(struct file *file, struct page *page) | |
1706 | { | |
1707 | return mpage_readpage(page, ext3_get_block); | |
1708 | } | |
1709 | ||
1710 | static int | |
1711 | ext3_readpages(struct file *file, struct address_space *mapping, | |
1712 | struct list_head *pages, unsigned nr_pages) | |
1713 | { | |
1714 | return mpage_readpages(mapping, pages, nr_pages, ext3_get_block); | |
1715 | } | |
1716 | ||
2ff28e22 | 1717 | static void ext3_invalidatepage(struct page *page, unsigned long offset) |
1da177e4 LT |
1718 | { |
1719 | journal_t *journal = EXT3_JOURNAL(page->mapping->host); | |
1720 | ||
1721 | /* | |
1722 | * If it's a full truncate we just forget about the pending dirtying | |
1723 | */ | |
1724 | if (offset == 0) | |
1725 | ClearPageChecked(page); | |
1726 | ||
2ff28e22 | 1727 | journal_invalidatepage(journal, page, offset); |
1da177e4 LT |
1728 | } |
1729 | ||
27496a8c | 1730 | static int ext3_releasepage(struct page *page, gfp_t wait) |
1da177e4 LT |
1731 | { |
1732 | journal_t *journal = EXT3_JOURNAL(page->mapping->host); | |
1733 | ||
1734 | WARN_ON(PageChecked(page)); | |
1735 | if (!page_has_buffers(page)) | |
1736 | return 0; | |
1737 | return journal_try_to_free_buffers(journal, page, wait); | |
1738 | } | |
1739 | ||
1740 | /* | |
1741 | * If the O_DIRECT write will extend the file then add this inode to the | |
1742 | * orphan list. So recovery will truncate it back to the original size | |
1743 | * if the machine crashes during the write. | |
1744 | * | |
1745 | * If the O_DIRECT write is intantiating holes inside i_size and the machine | |
bd1939de JK |
1746 | * crashes then stale disk data _may_ be exposed inside the file. But current |
1747 | * VFS code falls back into buffered path in that case so we are safe. | |
1da177e4 LT |
1748 | */ |
1749 | static ssize_t ext3_direct_IO(int rw, struct kiocb *iocb, | |
1750 | const struct iovec *iov, loff_t offset, | |
1751 | unsigned long nr_segs) | |
1752 | { | |
1753 | struct file *file = iocb->ki_filp; | |
1754 | struct inode *inode = file->f_mapping->host; | |
1755 | struct ext3_inode_info *ei = EXT3_I(inode); | |
bd1939de | 1756 | handle_t *handle; |
1da177e4 LT |
1757 | ssize_t ret; |
1758 | int orphan = 0; | |
1759 | size_t count = iov_length(iov, nr_segs); | |
ea0174a7 | 1760 | int retries = 0; |
1da177e4 LT |
1761 | |
1762 | if (rw == WRITE) { | |
1763 | loff_t final_size = offset + count; | |
1764 | ||
1da177e4 | 1765 | if (final_size > inode->i_size) { |
bd1939de JK |
1766 | /* Credits for sb + inode write */ |
1767 | handle = ext3_journal_start(inode, 2); | |
1768 | if (IS_ERR(handle)) { | |
1769 | ret = PTR_ERR(handle); | |
1770 | goto out; | |
1771 | } | |
1da177e4 | 1772 | ret = ext3_orphan_add(handle, inode); |
bd1939de JK |
1773 | if (ret) { |
1774 | ext3_journal_stop(handle); | |
1775 | goto out; | |
1776 | } | |
1da177e4 LT |
1777 | orphan = 1; |
1778 | ei->i_disksize = inode->i_size; | |
bd1939de | 1779 | ext3_journal_stop(handle); |
1da177e4 LT |
1780 | } |
1781 | } | |
1782 | ||
ea0174a7 | 1783 | retry: |
ae6ddcc5 | 1784 | ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, |
1da177e4 | 1785 | offset, nr_segs, |
f91a2ad2 | 1786 | ext3_get_block, NULL); |
eafdc7d1 CH |
1787 | /* |
1788 | * In case of error extending write may have instantiated a few | |
1789 | * blocks outside i_size. Trim these off again. | |
1790 | */ | |
1791 | if (unlikely((rw & WRITE) && ret < 0)) { | |
1792 | loff_t isize = i_size_read(inode); | |
1793 | loff_t end = offset + iov_length(iov, nr_segs); | |
1794 | ||
1795 | if (end > isize) | |
1796 | vmtruncate(inode, isize); | |
1797 | } | |
ea0174a7 ES |
1798 | if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries)) |
1799 | goto retry; | |
1da177e4 | 1800 | |
bd1939de | 1801 | if (orphan) { |
1da177e4 LT |
1802 | int err; |
1803 | ||
bd1939de JK |
1804 | /* Credits for sb + inode write */ |
1805 | handle = ext3_journal_start(inode, 2); | |
1806 | if (IS_ERR(handle)) { | |
1807 | /* This is really bad luck. We've written the data | |
7eb4969e JK |
1808 | * but cannot extend i_size. Truncate allocated blocks |
1809 | * and pretend the write failed... */ | |
1810 | ext3_truncate(inode); | |
bd1939de JK |
1811 | ret = PTR_ERR(handle); |
1812 | goto out; | |
1813 | } | |
1814 | if (inode->i_nlink) | |
1da177e4 | 1815 | ext3_orphan_del(handle, inode); |
bd1939de | 1816 | if (ret > 0) { |
1da177e4 LT |
1817 | loff_t end = offset + ret; |
1818 | if (end > inode->i_size) { | |
1819 | ei->i_disksize = end; | |
1820 | i_size_write(inode, end); | |
1821 | /* | |
1822 | * We're going to return a positive `ret' | |
1823 | * here due to non-zero-length I/O, so there's | |
1824 | * no way of reporting error returns from | |
1825 | * ext3_mark_inode_dirty() to userspace. So | |
1826 | * ignore it. | |
1827 | */ | |
1828 | ext3_mark_inode_dirty(handle, inode); | |
1829 | } | |
1830 | } | |
1831 | err = ext3_journal_stop(handle); | |
1832 | if (ret == 0) | |
1833 | ret = err; | |
1834 | } | |
1835 | out: | |
1836 | return ret; | |
1837 | } | |
1838 | ||
1839 | /* | |
1840 | * Pages can be marked dirty completely asynchronously from ext3's journalling | |
1841 | * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do | |
1842 | * much here because ->set_page_dirty is called under VFS locks. The page is | |
1843 | * not necessarily locked. | |
1844 | * | |
1845 | * We cannot just dirty the page and leave attached buffers clean, because the | |
1846 | * buffers' dirty state is "definitive". We cannot just set the buffers dirty | |
1847 | * or jbddirty because all the journalling code will explode. | |
1848 | * | |
1849 | * So what we do is to mark the page "pending dirty" and next time writepage | |
1850 | * is called, propagate that into the buffers appropriately. | |
1851 | */ | |
1852 | static int ext3_journalled_set_page_dirty(struct page *page) | |
1853 | { | |
1854 | SetPageChecked(page); | |
1855 | return __set_page_dirty_nobuffers(page); | |
1856 | } | |
1857 | ||
f5e54d6e | 1858 | static const struct address_space_operations ext3_ordered_aops = { |
8ab22b9a HH |
1859 | .readpage = ext3_readpage, |
1860 | .readpages = ext3_readpages, | |
1861 | .writepage = ext3_ordered_writepage, | |
1862 | .sync_page = block_sync_page, | |
1863 | .write_begin = ext3_write_begin, | |
1864 | .write_end = ext3_ordered_write_end, | |
1865 | .bmap = ext3_bmap, | |
1866 | .invalidatepage = ext3_invalidatepage, | |
1867 | .releasepage = ext3_releasepage, | |
1868 | .direct_IO = ext3_direct_IO, | |
1869 | .migratepage = buffer_migrate_page, | |
1870 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 1871 | .error_remove_page = generic_error_remove_page, |
1da177e4 LT |
1872 | }; |
1873 | ||
f5e54d6e | 1874 | static const struct address_space_operations ext3_writeback_aops = { |
8ab22b9a HH |
1875 | .readpage = ext3_readpage, |
1876 | .readpages = ext3_readpages, | |
1877 | .writepage = ext3_writeback_writepage, | |
1878 | .sync_page = block_sync_page, | |
1879 | .write_begin = ext3_write_begin, | |
1880 | .write_end = ext3_writeback_write_end, | |
1881 | .bmap = ext3_bmap, | |
1882 | .invalidatepage = ext3_invalidatepage, | |
1883 | .releasepage = ext3_releasepage, | |
1884 | .direct_IO = ext3_direct_IO, | |
1885 | .migratepage = buffer_migrate_page, | |
1886 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 1887 | .error_remove_page = generic_error_remove_page, |
1da177e4 LT |
1888 | }; |
1889 | ||
f5e54d6e | 1890 | static const struct address_space_operations ext3_journalled_aops = { |
8ab22b9a HH |
1891 | .readpage = ext3_readpage, |
1892 | .readpages = ext3_readpages, | |
1893 | .writepage = ext3_journalled_writepage, | |
1894 | .sync_page = block_sync_page, | |
1895 | .write_begin = ext3_write_begin, | |
1896 | .write_end = ext3_journalled_write_end, | |
1897 | .set_page_dirty = ext3_journalled_set_page_dirty, | |
1898 | .bmap = ext3_bmap, | |
1899 | .invalidatepage = ext3_invalidatepage, | |
1900 | .releasepage = ext3_releasepage, | |
1901 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 1902 | .error_remove_page = generic_error_remove_page, |
1da177e4 LT |
1903 | }; |
1904 | ||
1905 | void ext3_set_aops(struct inode *inode) | |
1906 | { | |
1907 | if (ext3_should_order_data(inode)) | |
1908 | inode->i_mapping->a_ops = &ext3_ordered_aops; | |
1909 | else if (ext3_should_writeback_data(inode)) | |
1910 | inode->i_mapping->a_ops = &ext3_writeback_aops; | |
1911 | else | |
1912 | inode->i_mapping->a_ops = &ext3_journalled_aops; | |
1913 | } | |
1914 | ||
1915 | /* | |
1916 | * ext3_block_truncate_page() zeroes out a mapping from file offset `from' | |
1917 | * up to the end of the block which corresponds to `from'. | |
1918 | * This required during truncate. We need to physically zero the tail end | |
1919 | * of that block so it doesn't yield old data if the file is later grown. | |
1920 | */ | |
1921 | static int ext3_block_truncate_page(handle_t *handle, struct page *page, | |
1922 | struct address_space *mapping, loff_t from) | |
1923 | { | |
43d23f90 | 1924 | ext3_fsblk_t index = from >> PAGE_CACHE_SHIFT; |
1da177e4 LT |
1925 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
1926 | unsigned blocksize, iblock, length, pos; | |
1927 | struct inode *inode = mapping->host; | |
1928 | struct buffer_head *bh; | |
1929 | int err = 0; | |
1da177e4 LT |
1930 | |
1931 | blocksize = inode->i_sb->s_blocksize; | |
1932 | length = blocksize - (offset & (blocksize - 1)); | |
1933 | iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
1934 | ||
1935 | /* | |
1936 | * For "nobh" option, we can only work if we don't need to | |
1937 | * read-in the page - otherwise we create buffers to do the IO. | |
1938 | */ | |
cd6ef84e BP |
1939 | if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && |
1940 | ext3_should_writeback_data(inode) && PageUptodate(page)) { | |
eebd2aa3 | 1941 | zero_user(page, offset, length); |
cd6ef84e BP |
1942 | set_page_dirty(page); |
1943 | goto unlock; | |
1da177e4 LT |
1944 | } |
1945 | ||
1946 | if (!page_has_buffers(page)) | |
1947 | create_empty_buffers(page, blocksize, 0); | |
1948 | ||
1949 | /* Find the buffer that contains "offset" */ | |
1950 | bh = page_buffers(page); | |
1951 | pos = blocksize; | |
1952 | while (offset >= pos) { | |
1953 | bh = bh->b_this_page; | |
1954 | iblock++; | |
1955 | pos += blocksize; | |
1956 | } | |
1957 | ||
1958 | err = 0; | |
1959 | if (buffer_freed(bh)) { | |
1960 | BUFFER_TRACE(bh, "freed: skip"); | |
1961 | goto unlock; | |
1962 | } | |
1963 | ||
1964 | if (!buffer_mapped(bh)) { | |
1965 | BUFFER_TRACE(bh, "unmapped"); | |
1966 | ext3_get_block(inode, iblock, bh, 0); | |
1967 | /* unmapped? It's a hole - nothing to do */ | |
1968 | if (!buffer_mapped(bh)) { | |
1969 | BUFFER_TRACE(bh, "still unmapped"); | |
1970 | goto unlock; | |
1971 | } | |
1972 | } | |
1973 | ||
1974 | /* Ok, it's mapped. Make sure it's up-to-date */ | |
1975 | if (PageUptodate(page)) | |
1976 | set_buffer_uptodate(bh); | |
1977 | ||
1978 | if (!buffer_uptodate(bh)) { | |
1979 | err = -EIO; | |
1980 | ll_rw_block(READ, 1, &bh); | |
1981 | wait_on_buffer(bh); | |
1982 | /* Uhhuh. Read error. Complain and punt. */ | |
1983 | if (!buffer_uptodate(bh)) | |
1984 | goto unlock; | |
1985 | } | |
1986 | ||
1987 | if (ext3_should_journal_data(inode)) { | |
1988 | BUFFER_TRACE(bh, "get write access"); | |
1989 | err = ext3_journal_get_write_access(handle, bh); | |
1990 | if (err) | |
1991 | goto unlock; | |
1992 | } | |
1993 | ||
eebd2aa3 | 1994 | zero_user(page, offset, length); |
1da177e4 LT |
1995 | BUFFER_TRACE(bh, "zeroed end of block"); |
1996 | ||
1997 | err = 0; | |
1998 | if (ext3_should_journal_data(inode)) { | |
1999 | err = ext3_journal_dirty_metadata(handle, bh); | |
2000 | } else { | |
2001 | if (ext3_should_order_data(inode)) | |
2002 | err = ext3_journal_dirty_data(handle, bh); | |
2003 | mark_buffer_dirty(bh); | |
2004 | } | |
2005 | ||
2006 | unlock: | |
2007 | unlock_page(page); | |
2008 | page_cache_release(page); | |
2009 | return err; | |
2010 | } | |
2011 | ||
2012 | /* | |
2013 | * Probably it should be a library function... search for first non-zero word | |
2014 | * or memcmp with zero_page, whatever is better for particular architecture. | |
2015 | * Linus? | |
2016 | */ | |
2017 | static inline int all_zeroes(__le32 *p, __le32 *q) | |
2018 | { | |
2019 | while (p < q) | |
2020 | if (*p++) | |
2021 | return 0; | |
2022 | return 1; | |
2023 | } | |
2024 | ||
2025 | /** | |
2026 | * ext3_find_shared - find the indirect blocks for partial truncation. | |
2027 | * @inode: inode in question | |
2028 | * @depth: depth of the affected branch | |
2029 | * @offsets: offsets of pointers in that branch (see ext3_block_to_path) | |
2030 | * @chain: place to store the pointers to partial indirect blocks | |
2031 | * @top: place to the (detached) top of branch | |
2032 | * | |
2033 | * This is a helper function used by ext3_truncate(). | |
2034 | * | |
2035 | * When we do truncate() we may have to clean the ends of several | |
2036 | * indirect blocks but leave the blocks themselves alive. Block is | |
2037 | * partially truncated if some data below the new i_size is refered | |
2038 | * from it (and it is on the path to the first completely truncated | |
2039 | * data block, indeed). We have to free the top of that path along | |
2040 | * with everything to the right of the path. Since no allocation | |
2041 | * past the truncation point is possible until ext3_truncate() | |
2042 | * finishes, we may safely do the latter, but top of branch may | |
2043 | * require special attention - pageout below the truncation point | |
2044 | * might try to populate it. | |
2045 | * | |
2046 | * We atomically detach the top of branch from the tree, store the | |
2047 | * block number of its root in *@top, pointers to buffer_heads of | |
2048 | * partially truncated blocks - in @chain[].bh and pointers to | |
2049 | * their last elements that should not be removed - in | |
2050 | * @chain[].p. Return value is the pointer to last filled element | |
2051 | * of @chain. | |
2052 | * | |
2053 | * The work left to caller to do the actual freeing of subtrees: | |
2054 | * a) free the subtree starting from *@top | |
2055 | * b) free the subtrees whose roots are stored in | |
2056 | * (@chain[i].p+1 .. end of @chain[i].bh->b_data) | |
2057 | * c) free the subtrees growing from the inode past the @chain[0]. | |
2058 | * (no partially truncated stuff there). */ | |
2059 | ||
d6859bfc AM |
2060 | static Indirect *ext3_find_shared(struct inode *inode, int depth, |
2061 | int offsets[4], Indirect chain[4], __le32 *top) | |
1da177e4 LT |
2062 | { |
2063 | Indirect *partial, *p; | |
2064 | int k, err; | |
2065 | ||
2066 | *top = 0; | |
bf48aabb | 2067 | /* Make k index the deepest non-null offset + 1 */ |
1da177e4 LT |
2068 | for (k = depth; k > 1 && !offsets[k-1]; k--) |
2069 | ; | |
2070 | partial = ext3_get_branch(inode, k, offsets, chain, &err); | |
2071 | /* Writer: pointers */ | |
2072 | if (!partial) | |
2073 | partial = chain + k-1; | |
2074 | /* | |
2075 | * If the branch acquired continuation since we've looked at it - | |
2076 | * fine, it should all survive and (new) top doesn't belong to us. | |
2077 | */ | |
2078 | if (!partial->key && *partial->p) | |
2079 | /* Writer: end */ | |
2080 | goto no_top; | |
2081 | for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--) | |
2082 | ; | |
2083 | /* | |
2084 | * OK, we've found the last block that must survive. The rest of our | |
2085 | * branch should be detached before unlocking. However, if that rest | |
2086 | * of branch is all ours and does not grow immediately from the inode | |
2087 | * it's easier to cheat and just decrement partial->p. | |
2088 | */ | |
2089 | if (p == chain + k - 1 && p > chain) { | |
2090 | p->p--; | |
2091 | } else { | |
2092 | *top = *p->p; | |
2093 | /* Nope, don't do this in ext3. Must leave the tree intact */ | |
2094 | #if 0 | |
2095 | *p->p = 0; | |
2096 | #endif | |
2097 | } | |
2098 | /* Writer: end */ | |
2099 | ||
d6859bfc | 2100 | while(partial > p) { |
1da177e4 LT |
2101 | brelse(partial->bh); |
2102 | partial--; | |
2103 | } | |
2104 | no_top: | |
2105 | return partial; | |
2106 | } | |
2107 | ||
2108 | /* | |
2109 | * Zero a number of block pointers in either an inode or an indirect block. | |
2110 | * If we restart the transaction we must again get write access to the | |
2111 | * indirect block for further modification. | |
2112 | * | |
2113 | * We release `count' blocks on disk, but (last - first) may be greater | |
2114 | * than `count' because there can be holes in there. | |
2115 | */ | |
d6859bfc | 2116 | static void ext3_clear_blocks(handle_t *handle, struct inode *inode, |
43d23f90 | 2117 | struct buffer_head *bh, ext3_fsblk_t block_to_free, |
d6859bfc | 2118 | unsigned long count, __le32 *first, __le32 *last) |
1da177e4 LT |
2119 | { |
2120 | __le32 *p; | |
2121 | if (try_to_extend_transaction(handle, inode)) { | |
2122 | if (bh) { | |
2123 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
2124 | ext3_journal_dirty_metadata(handle, bh); | |
2125 | } | |
2126 | ext3_mark_inode_dirty(handle, inode); | |
00171d3c | 2127 | truncate_restart_transaction(handle, inode); |
1da177e4 LT |
2128 | if (bh) { |
2129 | BUFFER_TRACE(bh, "retaking write access"); | |
2130 | ext3_journal_get_write_access(handle, bh); | |
2131 | } | |
2132 | } | |
2133 | ||
2134 | /* | |
2135 | * Any buffers which are on the journal will be in memory. We find | |
2136 | * them on the hash table so journal_revoke() will run journal_forget() | |
2137 | * on them. We've already detached each block from the file, so | |
2138 | * bforget() in journal_forget() should be safe. | |
2139 | * | |
2140 | * AKPM: turn on bforget in journal_forget()!!! | |
2141 | */ | |
2142 | for (p = first; p < last; p++) { | |
2143 | u32 nr = le32_to_cpu(*p); | |
2144 | if (nr) { | |
2145 | struct buffer_head *bh; | |
2146 | ||
2147 | *p = 0; | |
2148 | bh = sb_find_get_block(inode->i_sb, nr); | |
2149 | ext3_forget(handle, 0, inode, bh, nr); | |
2150 | } | |
2151 | } | |
2152 | ||
2153 | ext3_free_blocks(handle, inode, block_to_free, count); | |
2154 | } | |
2155 | ||
2156 | /** | |
2157 | * ext3_free_data - free a list of data blocks | |
2158 | * @handle: handle for this transaction | |
2159 | * @inode: inode we are dealing with | |
2160 | * @this_bh: indirect buffer_head which contains *@first and *@last | |
2161 | * @first: array of block numbers | |
2162 | * @last: points immediately past the end of array | |
2163 | * | |
2164 | * We are freeing all blocks refered from that array (numbers are stored as | |
2165 | * little-endian 32-bit) and updating @inode->i_blocks appropriately. | |
2166 | * | |
2167 | * We accumulate contiguous runs of blocks to free. Conveniently, if these | |
2168 | * blocks are contiguous then releasing them at one time will only affect one | |
2169 | * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't | |
2170 | * actually use a lot of journal space. | |
2171 | * | |
2172 | * @this_bh will be %NULL if @first and @last point into the inode's direct | |
2173 | * block pointers. | |
2174 | */ | |
2175 | static void ext3_free_data(handle_t *handle, struct inode *inode, | |
2176 | struct buffer_head *this_bh, | |
2177 | __le32 *first, __le32 *last) | |
2178 | { | |
43d23f90 | 2179 | ext3_fsblk_t block_to_free = 0; /* Starting block # of a run */ |
ae6ddcc5 | 2180 | unsigned long count = 0; /* Number of blocks in the run */ |
1da177e4 LT |
2181 | __le32 *block_to_free_p = NULL; /* Pointer into inode/ind |
2182 | corresponding to | |
2183 | block_to_free */ | |
43d23f90 | 2184 | ext3_fsblk_t nr; /* Current block # */ |
1da177e4 LT |
2185 | __le32 *p; /* Pointer into inode/ind |
2186 | for current block */ | |
2187 | int err; | |
2188 | ||
2189 | if (this_bh) { /* For indirect block */ | |
2190 | BUFFER_TRACE(this_bh, "get_write_access"); | |
2191 | err = ext3_journal_get_write_access(handle, this_bh); | |
2192 | /* Important: if we can't update the indirect pointers | |
2193 | * to the blocks, we can't free them. */ | |
2194 | if (err) | |
2195 | return; | |
2196 | } | |
2197 | ||
2198 | for (p = first; p < last; p++) { | |
2199 | nr = le32_to_cpu(*p); | |
2200 | if (nr) { | |
2201 | /* accumulate blocks to free if they're contiguous */ | |
2202 | if (count == 0) { | |
2203 | block_to_free = nr; | |
2204 | block_to_free_p = p; | |
2205 | count = 1; | |
2206 | } else if (nr == block_to_free + count) { | |
2207 | count++; | |
2208 | } else { | |
ae6ddcc5 | 2209 | ext3_clear_blocks(handle, inode, this_bh, |
1da177e4 LT |
2210 | block_to_free, |
2211 | count, block_to_free_p, p); | |
2212 | block_to_free = nr; | |
2213 | block_to_free_p = p; | |
2214 | count = 1; | |
2215 | } | |
2216 | } | |
2217 | } | |
2218 | ||
2219 | if (count > 0) | |
2220 | ext3_clear_blocks(handle, inode, this_bh, block_to_free, | |
2221 | count, block_to_free_p, p); | |
2222 | ||
2223 | if (this_bh) { | |
2224 | BUFFER_TRACE(this_bh, "call ext3_journal_dirty_metadata"); | |
3ccc3167 DG |
2225 | |
2226 | /* | |
2227 | * The buffer head should have an attached journal head at this | |
2228 | * point. However, if the data is corrupted and an indirect | |
2229 | * block pointed to itself, it would have been detached when | |
2230 | * the block was cleared. Check for this instead of OOPSing. | |
2231 | */ | |
2232 | if (bh2jh(this_bh)) | |
2233 | ext3_journal_dirty_metadata(handle, this_bh); | |
2234 | else | |
2235 | ext3_error(inode->i_sb, "ext3_free_data", | |
2236 | "circular indirect block detected, " | |
2237 | "inode=%lu, block=%llu", | |
2238 | inode->i_ino, | |
2239 | (unsigned long long)this_bh->b_blocknr); | |
1da177e4 LT |
2240 | } |
2241 | } | |
2242 | ||
2243 | /** | |
2244 | * ext3_free_branches - free an array of branches | |
2245 | * @handle: JBD handle for this transaction | |
2246 | * @inode: inode we are dealing with | |
2247 | * @parent_bh: the buffer_head which contains *@first and *@last | |
2248 | * @first: array of block numbers | |
2249 | * @last: pointer immediately past the end of array | |
2250 | * @depth: depth of the branches to free | |
2251 | * | |
2252 | * We are freeing all blocks refered from these branches (numbers are | |
2253 | * stored as little-endian 32-bit) and updating @inode->i_blocks | |
2254 | * appropriately. | |
2255 | */ | |
2256 | static void ext3_free_branches(handle_t *handle, struct inode *inode, | |
2257 | struct buffer_head *parent_bh, | |
2258 | __le32 *first, __le32 *last, int depth) | |
2259 | { | |
43d23f90 | 2260 | ext3_fsblk_t nr; |
1da177e4 LT |
2261 | __le32 *p; |
2262 | ||
2263 | if (is_handle_aborted(handle)) | |
2264 | return; | |
2265 | ||
2266 | if (depth--) { | |
2267 | struct buffer_head *bh; | |
2268 | int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
2269 | p = last; | |
2270 | while (--p >= first) { | |
2271 | nr = le32_to_cpu(*p); | |
2272 | if (!nr) | |
2273 | continue; /* A hole */ | |
2274 | ||
2275 | /* Go read the buffer for the next level down */ | |
2276 | bh = sb_bread(inode->i_sb, nr); | |
2277 | ||
2278 | /* | |
2279 | * A read failure? Report error and clear slot | |
2280 | * (should be rare). | |
2281 | */ | |
2282 | if (!bh) { | |
2283 | ext3_error(inode->i_sb, "ext3_free_branches", | |
eee194e7 | 2284 | "Read failure, inode=%lu, block="E3FSBLK, |
1da177e4 LT |
2285 | inode->i_ino, nr); |
2286 | continue; | |
2287 | } | |
2288 | ||
2289 | /* This zaps the entire block. Bottom up. */ | |
2290 | BUFFER_TRACE(bh, "free child branches"); | |
2291 | ext3_free_branches(handle, inode, bh, | |
2292 | (__le32*)bh->b_data, | |
2293 | (__le32*)bh->b_data + addr_per_block, | |
2294 | depth); | |
2295 | ||
2296 | /* | |
2297 | * We've probably journalled the indirect block several | |
2298 | * times during the truncate. But it's no longer | |
2299 | * needed and we now drop it from the transaction via | |
2300 | * journal_revoke(). | |
2301 | * | |
2302 | * That's easy if it's exclusively part of this | |
2303 | * transaction. But if it's part of the committing | |
2304 | * transaction then journal_forget() will simply | |
2305 | * brelse() it. That means that if the underlying | |
2306 | * block is reallocated in ext3_get_block(), | |
2307 | * unmap_underlying_metadata() will find this block | |
2308 | * and will try to get rid of it. damn, damn. | |
2309 | * | |
2310 | * If this block has already been committed to the | |
2311 | * journal, a revoke record will be written. And | |
2312 | * revoke records must be emitted *before* clearing | |
2313 | * this block's bit in the bitmaps. | |
2314 | */ | |
2315 | ext3_forget(handle, 1, inode, bh, bh->b_blocknr); | |
2316 | ||
2317 | /* | |
2318 | * Everything below this this pointer has been | |
2319 | * released. Now let this top-of-subtree go. | |
2320 | * | |
2321 | * We want the freeing of this indirect block to be | |
2322 | * atomic in the journal with the updating of the | |
2323 | * bitmap block which owns it. So make some room in | |
2324 | * the journal. | |
2325 | * | |
2326 | * We zero the parent pointer *after* freeing its | |
2327 | * pointee in the bitmaps, so if extend_transaction() | |
2328 | * for some reason fails to put the bitmap changes and | |
2329 | * the release into the same transaction, recovery | |
2330 | * will merely complain about releasing a free block, | |
2331 | * rather than leaking blocks. | |
2332 | */ | |
2333 | if (is_handle_aborted(handle)) | |
2334 | return; | |
2335 | if (try_to_extend_transaction(handle, inode)) { | |
2336 | ext3_mark_inode_dirty(handle, inode); | |
00171d3c | 2337 | truncate_restart_transaction(handle, inode); |
1da177e4 LT |
2338 | } |
2339 | ||
2340 | ext3_free_blocks(handle, inode, nr, 1); | |
2341 | ||
2342 | if (parent_bh) { | |
2343 | /* | |
2344 | * The block which we have just freed is | |
2345 | * pointed to by an indirect block: journal it | |
2346 | */ | |
2347 | BUFFER_TRACE(parent_bh, "get_write_access"); | |
2348 | if (!ext3_journal_get_write_access(handle, | |
2349 | parent_bh)){ | |
2350 | *p = 0; | |
2351 | BUFFER_TRACE(parent_bh, | |
2352 | "call ext3_journal_dirty_metadata"); | |
ae6ddcc5 | 2353 | ext3_journal_dirty_metadata(handle, |
1da177e4 LT |
2354 | parent_bh); |
2355 | } | |
2356 | } | |
2357 | } | |
2358 | } else { | |
2359 | /* We have reached the bottom of the tree. */ | |
2360 | BUFFER_TRACE(parent_bh, "free data blocks"); | |
2361 | ext3_free_data(handle, inode, parent_bh, first, last); | |
2362 | } | |
2363 | } | |
2364 | ||
ae76dd9a DG |
2365 | int ext3_can_truncate(struct inode *inode) |
2366 | { | |
2367 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | |
2368 | return 0; | |
2369 | if (S_ISREG(inode->i_mode)) | |
2370 | return 1; | |
2371 | if (S_ISDIR(inode->i_mode)) | |
2372 | return 1; | |
2373 | if (S_ISLNK(inode->i_mode)) | |
2374 | return !ext3_inode_is_fast_symlink(inode); | |
2375 | return 0; | |
2376 | } | |
2377 | ||
1da177e4 LT |
2378 | /* |
2379 | * ext3_truncate() | |
2380 | * | |
2381 | * We block out ext3_get_block() block instantiations across the entire | |
2382 | * transaction, and VFS/VM ensures that ext3_truncate() cannot run | |
2383 | * simultaneously on behalf of the same inode. | |
2384 | * | |
2385 | * As we work through the truncate and commmit bits of it to the journal there | |
2386 | * is one core, guiding principle: the file's tree must always be consistent on | |
2387 | * disk. We must be able to restart the truncate after a crash. | |
2388 | * | |
2389 | * The file's tree may be transiently inconsistent in memory (although it | |
2390 | * probably isn't), but whenever we close off and commit a journal transaction, | |
2391 | * the contents of (the filesystem + the journal) must be consistent and | |
2392 | * restartable. It's pretty simple, really: bottom up, right to left (although | |
2393 | * left-to-right works OK too). | |
2394 | * | |
2395 | * Note that at recovery time, journal replay occurs *before* the restart of | |
2396 | * truncate against the orphan inode list. | |
2397 | * | |
2398 | * The committed inode has the new, desired i_size (which is the same as | |
2399 | * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see | |
2400 | * that this inode's truncate did not complete and it will again call | |
2401 | * ext3_truncate() to have another go. So there will be instantiated blocks | |
2402 | * to the right of the truncation point in a crashed ext3 filesystem. But | |
2403 | * that's fine - as long as they are linked from the inode, the post-crash | |
2404 | * ext3_truncate() run will find them and release them. | |
2405 | */ | |
d6859bfc | 2406 | void ext3_truncate(struct inode *inode) |
1da177e4 LT |
2407 | { |
2408 | handle_t *handle; | |
2409 | struct ext3_inode_info *ei = EXT3_I(inode); | |
2410 | __le32 *i_data = ei->i_data; | |
2411 | int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
2412 | struct address_space *mapping = inode->i_mapping; | |
2413 | int offsets[4]; | |
2414 | Indirect chain[4]; | |
2415 | Indirect *partial; | |
2416 | __le32 nr = 0; | |
2417 | int n; | |
2418 | long last_block; | |
2419 | unsigned blocksize = inode->i_sb->s_blocksize; | |
2420 | struct page *page; | |
2421 | ||
ae76dd9a | 2422 | if (!ext3_can_truncate(inode)) |
ef43618a | 2423 | goto out_notrans; |
1da177e4 | 2424 | |
f7ab34ea | 2425 | if (inode->i_size == 0 && ext3_should_writeback_data(inode)) |
9df93939 | 2426 | ext3_set_inode_state(inode, EXT3_STATE_FLUSH_ON_CLOSE); |
f7ab34ea | 2427 | |
1da177e4 LT |
2428 | /* |
2429 | * We have to lock the EOF page here, because lock_page() nests | |
2430 | * outside journal_start(). | |
2431 | */ | |
2432 | if ((inode->i_size & (blocksize - 1)) == 0) { | |
2433 | /* Block boundary? Nothing to do */ | |
2434 | page = NULL; | |
2435 | } else { | |
2436 | page = grab_cache_page(mapping, | |
2437 | inode->i_size >> PAGE_CACHE_SHIFT); | |
2438 | if (!page) | |
ef43618a | 2439 | goto out_notrans; |
1da177e4 LT |
2440 | } |
2441 | ||
2442 | handle = start_transaction(inode); | |
2443 | if (IS_ERR(handle)) { | |
2444 | if (page) { | |
2445 | clear_highpage(page); | |
2446 | flush_dcache_page(page); | |
2447 | unlock_page(page); | |
2448 | page_cache_release(page); | |
2449 | } | |
ef43618a | 2450 | goto out_notrans; |
1da177e4 LT |
2451 | } |
2452 | ||
2453 | last_block = (inode->i_size + blocksize-1) | |
2454 | >> EXT3_BLOCK_SIZE_BITS(inode->i_sb); | |
2455 | ||
2456 | if (page) | |
2457 | ext3_block_truncate_page(handle, page, mapping, inode->i_size); | |
2458 | ||
2459 | n = ext3_block_to_path(inode, last_block, offsets, NULL); | |
2460 | if (n == 0) | |
2461 | goto out_stop; /* error */ | |
2462 | ||
2463 | /* | |
2464 | * OK. This truncate is going to happen. We add the inode to the | |
2465 | * orphan list, so that if this truncate spans multiple transactions, | |
2466 | * and we crash, we will resume the truncate when the filesystem | |
2467 | * recovers. It also marks the inode dirty, to catch the new size. | |
2468 | * | |
2469 | * Implication: the file must always be in a sane, consistent | |
2470 | * truncatable state while each transaction commits. | |
2471 | */ | |
2472 | if (ext3_orphan_add(handle, inode)) | |
2473 | goto out_stop; | |
2474 | ||
2475 | /* | |
2476 | * The orphan list entry will now protect us from any crash which | |
2477 | * occurs before the truncate completes, so it is now safe to propagate | |
2478 | * the new, shorter inode size (held for now in i_size) into the | |
2479 | * on-disk inode. We do this via i_disksize, which is the value which | |
2480 | * ext3 *really* writes onto the disk inode. | |
2481 | */ | |
2482 | ei->i_disksize = inode->i_size; | |
2483 | ||
2484 | /* | |
2485 | * From here we block out all ext3_get_block() callers who want to | |
2486 | * modify the block allocation tree. | |
2487 | */ | |
97461518 | 2488 | mutex_lock(&ei->truncate_mutex); |
1da177e4 LT |
2489 | |
2490 | if (n == 1) { /* direct blocks */ | |
2491 | ext3_free_data(handle, inode, NULL, i_data+offsets[0], | |
2492 | i_data + EXT3_NDIR_BLOCKS); | |
2493 | goto do_indirects; | |
2494 | } | |
2495 | ||
2496 | partial = ext3_find_shared(inode, n, offsets, chain, &nr); | |
2497 | /* Kill the top of shared branch (not detached) */ | |
2498 | if (nr) { | |
2499 | if (partial == chain) { | |
2500 | /* Shared branch grows from the inode */ | |
2501 | ext3_free_branches(handle, inode, NULL, | |
2502 | &nr, &nr+1, (chain+n-1) - partial); | |
2503 | *partial->p = 0; | |
2504 | /* | |
2505 | * We mark the inode dirty prior to restart, | |
2506 | * and prior to stop. No need for it here. | |
2507 | */ | |
2508 | } else { | |
2509 | /* Shared branch grows from an indirect block */ | |
2510 | BUFFER_TRACE(partial->bh, "get_write_access"); | |
2511 | ext3_free_branches(handle, inode, partial->bh, | |
2512 | partial->p, | |
2513 | partial->p+1, (chain+n-1) - partial); | |
2514 | } | |
2515 | } | |
2516 | /* Clear the ends of indirect blocks on the shared branch */ | |
2517 | while (partial > chain) { | |
2518 | ext3_free_branches(handle, inode, partial->bh, partial->p + 1, | |
2519 | (__le32*)partial->bh->b_data+addr_per_block, | |
2520 | (chain+n-1) - partial); | |
2521 | BUFFER_TRACE(partial->bh, "call brelse"); | |
2522 | brelse (partial->bh); | |
2523 | partial--; | |
2524 | } | |
2525 | do_indirects: | |
2526 | /* Kill the remaining (whole) subtrees */ | |
2527 | switch (offsets[0]) { | |
d6859bfc AM |
2528 | default: |
2529 | nr = i_data[EXT3_IND_BLOCK]; | |
2530 | if (nr) { | |
2531 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 1); | |
2532 | i_data[EXT3_IND_BLOCK] = 0; | |
2533 | } | |
2534 | case EXT3_IND_BLOCK: | |
2535 | nr = i_data[EXT3_DIND_BLOCK]; | |
2536 | if (nr) { | |
2537 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 2); | |
2538 | i_data[EXT3_DIND_BLOCK] = 0; | |
2539 | } | |
2540 | case EXT3_DIND_BLOCK: | |
2541 | nr = i_data[EXT3_TIND_BLOCK]; | |
2542 | if (nr) { | |
2543 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 3); | |
2544 | i_data[EXT3_TIND_BLOCK] = 0; | |
2545 | } | |
2546 | case EXT3_TIND_BLOCK: | |
2547 | ; | |
1da177e4 LT |
2548 | } |
2549 | ||
2550 | ext3_discard_reservation(inode); | |
2551 | ||
97461518 | 2552 | mutex_unlock(&ei->truncate_mutex); |
1da177e4 LT |
2553 | inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; |
2554 | ext3_mark_inode_dirty(handle, inode); | |
2555 | ||
d6859bfc AM |
2556 | /* |
2557 | * In a multi-transaction truncate, we only make the final transaction | |
2558 | * synchronous | |
2559 | */ | |
1da177e4 LT |
2560 | if (IS_SYNC(inode)) |
2561 | handle->h_sync = 1; | |
2562 | out_stop: | |
2563 | /* | |
2564 | * If this was a simple ftruncate(), and the file will remain alive | |
2565 | * then we need to clear up the orphan record which we created above. | |
2566 | * However, if this was a real unlink then we were called by | |
2567 | * ext3_delete_inode(), and we allow that function to clean up the | |
2568 | * orphan info for us. | |
2569 | */ | |
2570 | if (inode->i_nlink) | |
2571 | ext3_orphan_del(handle, inode); | |
2572 | ||
2573 | ext3_journal_stop(handle); | |
ef43618a JK |
2574 | return; |
2575 | out_notrans: | |
2576 | /* | |
2577 | * Delete the inode from orphan list so that it doesn't stay there | |
2578 | * forever and trigger assertion on umount. | |
2579 | */ | |
2580 | if (inode->i_nlink) | |
2581 | ext3_orphan_del(NULL, inode); | |
1da177e4 LT |
2582 | } |
2583 | ||
43d23f90 | 2584 | static ext3_fsblk_t ext3_get_inode_block(struct super_block *sb, |
1da177e4 LT |
2585 | unsigned long ino, struct ext3_iloc *iloc) |
2586 | { | |
e0e369a7 | 2587 | unsigned long block_group; |
43d23f90 MC |
2588 | unsigned long offset; |
2589 | ext3_fsblk_t block; | |
e0e369a7 | 2590 | struct ext3_group_desc *gdp; |
1da177e4 | 2591 | |
2ccb48eb NB |
2592 | if (!ext3_valid_inum(sb, ino)) { |
2593 | /* | |
2594 | * This error is already checked for in namei.c unless we are | |
2595 | * looking at an NFS filehandle, in which case no error | |
2596 | * report is needed | |
2597 | */ | |
1da177e4 LT |
2598 | return 0; |
2599 | } | |
2ccb48eb | 2600 | |
1da177e4 | 2601 | block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb); |
e0e369a7 AM |
2602 | gdp = ext3_get_group_desc(sb, block_group, NULL); |
2603 | if (!gdp) | |
1da177e4 | 2604 | return 0; |
1da177e4 LT |
2605 | /* |
2606 | * Figure out the offset within the block group inode table | |
2607 | */ | |
2608 | offset = ((ino - 1) % EXT3_INODES_PER_GROUP(sb)) * | |
2609 | EXT3_INODE_SIZE(sb); | |
e0e369a7 | 2610 | block = le32_to_cpu(gdp->bg_inode_table) + |
1da177e4 LT |
2611 | (offset >> EXT3_BLOCK_SIZE_BITS(sb)); |
2612 | ||
2613 | iloc->block_group = block_group; | |
2614 | iloc->offset = offset & (EXT3_BLOCK_SIZE(sb) - 1); | |
2615 | return block; | |
2616 | } | |
2617 | ||
2618 | /* | |
2619 | * ext3_get_inode_loc returns with an extra refcount against the inode's | |
2620 | * underlying buffer_head on success. If 'in_mem' is true, we have all | |
2621 | * data in memory that is needed to recreate the on-disk version of this | |
2622 | * inode. | |
2623 | */ | |
2624 | static int __ext3_get_inode_loc(struct inode *inode, | |
2625 | struct ext3_iloc *iloc, int in_mem) | |
2626 | { | |
43d23f90 | 2627 | ext3_fsblk_t block; |
1da177e4 LT |
2628 | struct buffer_head *bh; |
2629 | ||
2630 | block = ext3_get_inode_block(inode->i_sb, inode->i_ino, iloc); | |
2631 | if (!block) | |
2632 | return -EIO; | |
2633 | ||
2634 | bh = sb_getblk(inode->i_sb, block); | |
2635 | if (!bh) { | |
2636 | ext3_error (inode->i_sb, "ext3_get_inode_loc", | |
2637 | "unable to read inode block - " | |
43d23f90 MC |
2638 | "inode=%lu, block="E3FSBLK, |
2639 | inode->i_ino, block); | |
1da177e4 LT |
2640 | return -EIO; |
2641 | } | |
2642 | if (!buffer_uptodate(bh)) { | |
2643 | lock_buffer(bh); | |
95450f5a HK |
2644 | |
2645 | /* | |
2646 | * If the buffer has the write error flag, we have failed | |
2647 | * to write out another inode in the same block. In this | |
2648 | * case, we don't have to read the block because we may | |
2649 | * read the old inode data successfully. | |
2650 | */ | |
2651 | if (buffer_write_io_error(bh) && !buffer_uptodate(bh)) | |
2652 | set_buffer_uptodate(bh); | |
2653 | ||
1da177e4 LT |
2654 | if (buffer_uptodate(bh)) { |
2655 | /* someone brought it uptodate while we waited */ | |
2656 | unlock_buffer(bh); | |
2657 | goto has_buffer; | |
2658 | } | |
2659 | ||
2660 | /* | |
2661 | * If we have all information of the inode in memory and this | |
2662 | * is the only valid inode in the block, we need not read the | |
2663 | * block. | |
2664 | */ | |
2665 | if (in_mem) { | |
2666 | struct buffer_head *bitmap_bh; | |
2667 | struct ext3_group_desc *desc; | |
2668 | int inodes_per_buffer; | |
2669 | int inode_offset, i; | |
2670 | int block_group; | |
2671 | int start; | |
2672 | ||
2673 | block_group = (inode->i_ino - 1) / | |
2674 | EXT3_INODES_PER_GROUP(inode->i_sb); | |
2675 | inodes_per_buffer = bh->b_size / | |
2676 | EXT3_INODE_SIZE(inode->i_sb); | |
2677 | inode_offset = ((inode->i_ino - 1) % | |
2678 | EXT3_INODES_PER_GROUP(inode->i_sb)); | |
2679 | start = inode_offset & ~(inodes_per_buffer - 1); | |
2680 | ||
2681 | /* Is the inode bitmap in cache? */ | |
2682 | desc = ext3_get_group_desc(inode->i_sb, | |
2683 | block_group, NULL); | |
2684 | if (!desc) | |
2685 | goto make_io; | |
2686 | ||
2687 | bitmap_bh = sb_getblk(inode->i_sb, | |
2688 | le32_to_cpu(desc->bg_inode_bitmap)); | |
2689 | if (!bitmap_bh) | |
2690 | goto make_io; | |
2691 | ||
2692 | /* | |
2693 | * If the inode bitmap isn't in cache then the | |
2694 | * optimisation may end up performing two reads instead | |
2695 | * of one, so skip it. | |
2696 | */ | |
2697 | if (!buffer_uptodate(bitmap_bh)) { | |
2698 | brelse(bitmap_bh); | |
2699 | goto make_io; | |
2700 | } | |
2701 | for (i = start; i < start + inodes_per_buffer; i++) { | |
2702 | if (i == inode_offset) | |
2703 | continue; | |
2704 | if (ext3_test_bit(i, bitmap_bh->b_data)) | |
2705 | break; | |
2706 | } | |
2707 | brelse(bitmap_bh); | |
2708 | if (i == start + inodes_per_buffer) { | |
2709 | /* all other inodes are free, so skip I/O */ | |
2710 | memset(bh->b_data, 0, bh->b_size); | |
2711 | set_buffer_uptodate(bh); | |
2712 | unlock_buffer(bh); | |
2713 | goto has_buffer; | |
2714 | } | |
2715 | } | |
2716 | ||
2717 | make_io: | |
2718 | /* | |
2719 | * There are other valid inodes in the buffer, this inode | |
2720 | * has in-inode xattrs, or we don't have this inode in memory. | |
2721 | * Read the block from disk. | |
2722 | */ | |
2723 | get_bh(bh); | |
2724 | bh->b_end_io = end_buffer_read_sync; | |
caa38fb0 | 2725 | submit_bh(READ_META, bh); |
1da177e4 LT |
2726 | wait_on_buffer(bh); |
2727 | if (!buffer_uptodate(bh)) { | |
2728 | ext3_error(inode->i_sb, "ext3_get_inode_loc", | |
2729 | "unable to read inode block - " | |
43d23f90 | 2730 | "inode=%lu, block="E3FSBLK, |
1da177e4 LT |
2731 | inode->i_ino, block); |
2732 | brelse(bh); | |
2733 | return -EIO; | |
2734 | } | |
2735 | } | |
2736 | has_buffer: | |
2737 | iloc->bh = bh; | |
2738 | return 0; | |
2739 | } | |
2740 | ||
2741 | int ext3_get_inode_loc(struct inode *inode, struct ext3_iloc *iloc) | |
2742 | { | |
2743 | /* We have all inode data except xattrs in memory here. */ | |
2744 | return __ext3_get_inode_loc(inode, iloc, | |
9df93939 | 2745 | !ext3_test_inode_state(inode, EXT3_STATE_XATTR)); |
1da177e4 LT |
2746 | } |
2747 | ||
2748 | void ext3_set_inode_flags(struct inode *inode) | |
2749 | { | |
2750 | unsigned int flags = EXT3_I(inode)->i_flags; | |
2751 | ||
2752 | inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); | |
2753 | if (flags & EXT3_SYNC_FL) | |
2754 | inode->i_flags |= S_SYNC; | |
2755 | if (flags & EXT3_APPEND_FL) | |
2756 | inode->i_flags |= S_APPEND; | |
2757 | if (flags & EXT3_IMMUTABLE_FL) | |
2758 | inode->i_flags |= S_IMMUTABLE; | |
2759 | if (flags & EXT3_NOATIME_FL) | |
2760 | inode->i_flags |= S_NOATIME; | |
2761 | if (flags & EXT3_DIRSYNC_FL) | |
2762 | inode->i_flags |= S_DIRSYNC; | |
2763 | } | |
2764 | ||
28be5abb JK |
2765 | /* Propagate flags from i_flags to EXT3_I(inode)->i_flags */ |
2766 | void ext3_get_inode_flags(struct ext3_inode_info *ei) | |
2767 | { | |
2768 | unsigned int flags = ei->vfs_inode.i_flags; | |
2769 | ||
2770 | ei->i_flags &= ~(EXT3_SYNC_FL|EXT3_APPEND_FL| | |
2771 | EXT3_IMMUTABLE_FL|EXT3_NOATIME_FL|EXT3_DIRSYNC_FL); | |
2772 | if (flags & S_SYNC) | |
2773 | ei->i_flags |= EXT3_SYNC_FL; | |
2774 | if (flags & S_APPEND) | |
2775 | ei->i_flags |= EXT3_APPEND_FL; | |
2776 | if (flags & S_IMMUTABLE) | |
2777 | ei->i_flags |= EXT3_IMMUTABLE_FL; | |
2778 | if (flags & S_NOATIME) | |
2779 | ei->i_flags |= EXT3_NOATIME_FL; | |
2780 | if (flags & S_DIRSYNC) | |
2781 | ei->i_flags |= EXT3_DIRSYNC_FL; | |
2782 | } | |
2783 | ||
473043dc | 2784 | struct inode *ext3_iget(struct super_block *sb, unsigned long ino) |
1da177e4 LT |
2785 | { |
2786 | struct ext3_iloc iloc; | |
2787 | struct ext3_inode *raw_inode; | |
473043dc | 2788 | struct ext3_inode_info *ei; |
1da177e4 | 2789 | struct buffer_head *bh; |
473043dc | 2790 | struct inode *inode; |
fe8bc91c JK |
2791 | journal_t *journal = EXT3_SB(sb)->s_journal; |
2792 | transaction_t *transaction; | |
473043dc | 2793 | long ret; |
1da177e4 LT |
2794 | int block; |
2795 | ||
473043dc DH |
2796 | inode = iget_locked(sb, ino); |
2797 | if (!inode) | |
2798 | return ERR_PTR(-ENOMEM); | |
2799 | if (!(inode->i_state & I_NEW)) | |
2800 | return inode; | |
2801 | ||
2802 | ei = EXT3_I(inode); | |
1da177e4 LT |
2803 | ei->i_block_alloc_info = NULL; |
2804 | ||
473043dc DH |
2805 | ret = __ext3_get_inode_loc(inode, &iloc, 0); |
2806 | if (ret < 0) | |
1da177e4 LT |
2807 | goto bad_inode; |
2808 | bh = iloc.bh; | |
2809 | raw_inode = ext3_raw_inode(&iloc); | |
2810 | inode->i_mode = le16_to_cpu(raw_inode->i_mode); | |
2811 | inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); | |
2812 | inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); | |
2813 | if(!(test_opt (inode->i_sb, NO_UID32))) { | |
2814 | inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; | |
2815 | inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; | |
2816 | } | |
2817 | inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); | |
2818 | inode->i_size = le32_to_cpu(raw_inode->i_size); | |
4d7bf11d MR |
2819 | inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime); |
2820 | inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime); | |
2821 | inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime); | |
1da177e4 LT |
2822 | inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0; |
2823 | ||
de329820 | 2824 | ei->i_state_flags = 0; |
1da177e4 LT |
2825 | ei->i_dir_start_lookup = 0; |
2826 | ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); | |
2827 | /* We now have enough fields to check if the inode was active or not. | |
2828 | * This is needed because nfsd might try to access dead inodes | |
2829 | * the test is that same one that e2fsck uses | |
2830 | * NeilBrown 1999oct15 | |
2831 | */ | |
2832 | if (inode->i_nlink == 0) { | |
2833 | if (inode->i_mode == 0 || | |
2834 | !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ORPHAN_FS)) { | |
2835 | /* this inode is deleted */ | |
2836 | brelse (bh); | |
473043dc | 2837 | ret = -ESTALE; |
1da177e4 LT |
2838 | goto bad_inode; |
2839 | } | |
2840 | /* The only unlinked inodes we let through here have | |
2841 | * valid i_mode and are being read by the orphan | |
2842 | * recovery code: that's fine, we're about to complete | |
2843 | * the process of deleting those. */ | |
2844 | } | |
1da177e4 LT |
2845 | inode->i_blocks = le32_to_cpu(raw_inode->i_blocks); |
2846 | ei->i_flags = le32_to_cpu(raw_inode->i_flags); | |
2847 | #ifdef EXT3_FRAGMENTS | |
2848 | ei->i_faddr = le32_to_cpu(raw_inode->i_faddr); | |
2849 | ei->i_frag_no = raw_inode->i_frag; | |
2850 | ei->i_frag_size = raw_inode->i_fsize; | |
2851 | #endif | |
2852 | ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl); | |
2853 | if (!S_ISREG(inode->i_mode)) { | |
2854 | ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl); | |
2855 | } else { | |
2856 | inode->i_size |= | |
2857 | ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32; | |
2858 | } | |
2859 | ei->i_disksize = inode->i_size; | |
2860 | inode->i_generation = le32_to_cpu(raw_inode->i_generation); | |
2861 | ei->i_block_group = iloc.block_group; | |
2862 | /* | |
2863 | * NOTE! The in-memory inode i_data array is in little-endian order | |
2864 | * even on big-endian machines: we do NOT byteswap the block numbers! | |
2865 | */ | |
2866 | for (block = 0; block < EXT3_N_BLOCKS; block++) | |
2867 | ei->i_data[block] = raw_inode->i_block[block]; | |
2868 | INIT_LIST_HEAD(&ei->i_orphan); | |
2869 | ||
fe8bc91c JK |
2870 | /* |
2871 | * Set transaction id's of transactions that have to be committed | |
2872 | * to finish f[data]sync. We set them to currently running transaction | |
2873 | * as we cannot be sure that the inode or some of its metadata isn't | |
2874 | * part of the transaction - the inode could have been reclaimed and | |
2875 | * now it is reread from disk. | |
2876 | */ | |
2877 | if (journal) { | |
2878 | tid_t tid; | |
2879 | ||
2880 | spin_lock(&journal->j_state_lock); | |
2881 | if (journal->j_running_transaction) | |
2882 | transaction = journal->j_running_transaction; | |
2883 | else | |
2884 | transaction = journal->j_committing_transaction; | |
2885 | if (transaction) | |
2886 | tid = transaction->t_tid; | |
2887 | else | |
2888 | tid = journal->j_commit_sequence; | |
2889 | spin_unlock(&journal->j_state_lock); | |
2890 | atomic_set(&ei->i_sync_tid, tid); | |
2891 | atomic_set(&ei->i_datasync_tid, tid); | |
2892 | } | |
2893 | ||
1da177e4 LT |
2894 | if (inode->i_ino >= EXT3_FIRST_INO(inode->i_sb) + 1 && |
2895 | EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) { | |
2896 | /* | |
2897 | * When mke2fs creates big inodes it does not zero out | |
2898 | * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE, | |
2899 | * so ignore those first few inodes. | |
2900 | */ | |
2901 | ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); | |
2902 | if (EXT3_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > | |
e4a10a36 KK |
2903 | EXT3_INODE_SIZE(inode->i_sb)) { |
2904 | brelse (bh); | |
473043dc | 2905 | ret = -EIO; |
1da177e4 | 2906 | goto bad_inode; |
e4a10a36 | 2907 | } |
1da177e4 LT |
2908 | if (ei->i_extra_isize == 0) { |
2909 | /* The extra space is currently unused. Use it. */ | |
2910 | ei->i_extra_isize = sizeof(struct ext3_inode) - | |
2911 | EXT3_GOOD_OLD_INODE_SIZE; | |
2912 | } else { | |
2913 | __le32 *magic = (void *)raw_inode + | |
2914 | EXT3_GOOD_OLD_INODE_SIZE + | |
2915 | ei->i_extra_isize; | |
2916 | if (*magic == cpu_to_le32(EXT3_XATTR_MAGIC)) | |
9df93939 | 2917 | ext3_set_inode_state(inode, EXT3_STATE_XATTR); |
1da177e4 LT |
2918 | } |
2919 | } else | |
2920 | ei->i_extra_isize = 0; | |
2921 | ||
2922 | if (S_ISREG(inode->i_mode)) { | |
2923 | inode->i_op = &ext3_file_inode_operations; | |
2924 | inode->i_fop = &ext3_file_operations; | |
2925 | ext3_set_aops(inode); | |
2926 | } else if (S_ISDIR(inode->i_mode)) { | |
2927 | inode->i_op = &ext3_dir_inode_operations; | |
2928 | inode->i_fop = &ext3_dir_operations; | |
2929 | } else if (S_ISLNK(inode->i_mode)) { | |
b5ed3112 | 2930 | if (ext3_inode_is_fast_symlink(inode)) { |
1da177e4 | 2931 | inode->i_op = &ext3_fast_symlink_inode_operations; |
b5ed3112 DG |
2932 | nd_terminate_link(ei->i_data, inode->i_size, |
2933 | sizeof(ei->i_data) - 1); | |
2934 | } else { | |
1da177e4 LT |
2935 | inode->i_op = &ext3_symlink_inode_operations; |
2936 | ext3_set_aops(inode); | |
2937 | } | |
2938 | } else { | |
2939 | inode->i_op = &ext3_special_inode_operations; | |
2940 | if (raw_inode->i_block[0]) | |
2941 | init_special_inode(inode, inode->i_mode, | |
2942 | old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); | |
ae6ddcc5 | 2943 | else |
1da177e4 LT |
2944 | init_special_inode(inode, inode->i_mode, |
2945 | new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); | |
2946 | } | |
2947 | brelse (iloc.bh); | |
2948 | ext3_set_inode_flags(inode); | |
473043dc DH |
2949 | unlock_new_inode(inode); |
2950 | return inode; | |
1da177e4 LT |
2951 | |
2952 | bad_inode: | |
473043dc DH |
2953 | iget_failed(inode); |
2954 | return ERR_PTR(ret); | |
1da177e4 LT |
2955 | } |
2956 | ||
2957 | /* | |
2958 | * Post the struct inode info into an on-disk inode location in the | |
2959 | * buffer-cache. This gobbles the caller's reference to the | |
2960 | * buffer_head in the inode location struct. | |
2961 | * | |
2962 | * The caller must have write access to iloc->bh. | |
2963 | */ | |
ae6ddcc5 MC |
2964 | static int ext3_do_update_inode(handle_t *handle, |
2965 | struct inode *inode, | |
1da177e4 LT |
2966 | struct ext3_iloc *iloc) |
2967 | { | |
2968 | struct ext3_inode *raw_inode = ext3_raw_inode(iloc); | |
2969 | struct ext3_inode_info *ei = EXT3_I(inode); | |
2970 | struct buffer_head *bh = iloc->bh; | |
2971 | int err = 0, rc, block; | |
2972 | ||
4f003fd3 CM |
2973 | again: |
2974 | /* we can't allow multiple procs in here at once, its a bit racey */ | |
2975 | lock_buffer(bh); | |
2976 | ||
1da177e4 LT |
2977 | /* For fields not not tracking in the in-memory inode, |
2978 | * initialise them to zero for new inodes. */ | |
9df93939 | 2979 | if (ext3_test_inode_state(inode, EXT3_STATE_NEW)) |
1da177e4 LT |
2980 | memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size); |
2981 | ||
28be5abb | 2982 | ext3_get_inode_flags(ei); |
1da177e4 LT |
2983 | raw_inode->i_mode = cpu_to_le16(inode->i_mode); |
2984 | if(!(test_opt(inode->i_sb, NO_UID32))) { | |
2985 | raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid)); | |
2986 | raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid)); | |
2987 | /* | |
2988 | * Fix up interoperability with old kernels. Otherwise, old inodes get | |
2989 | * re-used with the upper 16 bits of the uid/gid intact | |
2990 | */ | |
2991 | if(!ei->i_dtime) { | |
2992 | raw_inode->i_uid_high = | |
2993 | cpu_to_le16(high_16_bits(inode->i_uid)); | |
2994 | raw_inode->i_gid_high = | |
2995 | cpu_to_le16(high_16_bits(inode->i_gid)); | |
2996 | } else { | |
2997 | raw_inode->i_uid_high = 0; | |
2998 | raw_inode->i_gid_high = 0; | |
2999 | } | |
3000 | } else { | |
3001 | raw_inode->i_uid_low = | |
3002 | cpu_to_le16(fs_high2lowuid(inode->i_uid)); | |
3003 | raw_inode->i_gid_low = | |
3004 | cpu_to_le16(fs_high2lowgid(inode->i_gid)); | |
3005 | raw_inode->i_uid_high = 0; | |
3006 | raw_inode->i_gid_high = 0; | |
3007 | } | |
3008 | raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); | |
3009 | raw_inode->i_size = cpu_to_le32(ei->i_disksize); | |
3010 | raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec); | |
3011 | raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); | |
3012 | raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); | |
3013 | raw_inode->i_blocks = cpu_to_le32(inode->i_blocks); | |
3014 | raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); | |
3015 | raw_inode->i_flags = cpu_to_le32(ei->i_flags); | |
3016 | #ifdef EXT3_FRAGMENTS | |
3017 | raw_inode->i_faddr = cpu_to_le32(ei->i_faddr); | |
3018 | raw_inode->i_frag = ei->i_frag_no; | |
3019 | raw_inode->i_fsize = ei->i_frag_size; | |
3020 | #endif | |
3021 | raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl); | |
3022 | if (!S_ISREG(inode->i_mode)) { | |
3023 | raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl); | |
3024 | } else { | |
3025 | raw_inode->i_size_high = | |
3026 | cpu_to_le32(ei->i_disksize >> 32); | |
3027 | if (ei->i_disksize > 0x7fffffffULL) { | |
3028 | struct super_block *sb = inode->i_sb; | |
3029 | if (!EXT3_HAS_RO_COMPAT_FEATURE(sb, | |
3030 | EXT3_FEATURE_RO_COMPAT_LARGE_FILE) || | |
3031 | EXT3_SB(sb)->s_es->s_rev_level == | |
3032 | cpu_to_le32(EXT3_GOOD_OLD_REV)) { | |
3033 | /* If this is the first large file | |
3034 | * created, add a flag to the superblock. | |
3035 | */ | |
4f003fd3 | 3036 | unlock_buffer(bh); |
1da177e4 LT |
3037 | err = ext3_journal_get_write_access(handle, |
3038 | EXT3_SB(sb)->s_sbh); | |
3039 | if (err) | |
3040 | goto out_brelse; | |
4f003fd3 | 3041 | |
1da177e4 LT |
3042 | ext3_update_dynamic_rev(sb); |
3043 | EXT3_SET_RO_COMPAT_FEATURE(sb, | |
3044 | EXT3_FEATURE_RO_COMPAT_LARGE_FILE); | |
1da177e4 LT |
3045 | handle->h_sync = 1; |
3046 | err = ext3_journal_dirty_metadata(handle, | |
3047 | EXT3_SB(sb)->s_sbh); | |
4f003fd3 CM |
3048 | /* get our lock and start over */ |
3049 | goto again; | |
1da177e4 LT |
3050 | } |
3051 | } | |
3052 | } | |
3053 | raw_inode->i_generation = cpu_to_le32(inode->i_generation); | |
3054 | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { | |
3055 | if (old_valid_dev(inode->i_rdev)) { | |
3056 | raw_inode->i_block[0] = | |
3057 | cpu_to_le32(old_encode_dev(inode->i_rdev)); | |
3058 | raw_inode->i_block[1] = 0; | |
3059 | } else { | |
3060 | raw_inode->i_block[0] = 0; | |
3061 | raw_inode->i_block[1] = | |
3062 | cpu_to_le32(new_encode_dev(inode->i_rdev)); | |
3063 | raw_inode->i_block[2] = 0; | |
3064 | } | |
3065 | } else for (block = 0; block < EXT3_N_BLOCKS; block++) | |
3066 | raw_inode->i_block[block] = ei->i_data[block]; | |
3067 | ||
ff87b37d | 3068 | if (ei->i_extra_isize) |
1da177e4 LT |
3069 | raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); |
3070 | ||
3071 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
4f003fd3 | 3072 | unlock_buffer(bh); |
1da177e4 LT |
3073 | rc = ext3_journal_dirty_metadata(handle, bh); |
3074 | if (!err) | |
3075 | err = rc; | |
9df93939 | 3076 | ext3_clear_inode_state(inode, EXT3_STATE_NEW); |
1da177e4 | 3077 | |
fe8bc91c | 3078 | atomic_set(&ei->i_sync_tid, handle->h_transaction->t_tid); |
1da177e4 LT |
3079 | out_brelse: |
3080 | brelse (bh); | |
3081 | ext3_std_error(inode->i_sb, err); | |
3082 | return err; | |
3083 | } | |
3084 | ||
3085 | /* | |
3086 | * ext3_write_inode() | |
3087 | * | |
3088 | * We are called from a few places: | |
3089 | * | |
3090 | * - Within generic_file_write() for O_SYNC files. | |
3091 | * Here, there will be no transaction running. We wait for any running | |
3092 | * trasnaction to commit. | |
3093 | * | |
3094 | * - Within sys_sync(), kupdate and such. | |
3095 | * We wait on commit, if tol to. | |
3096 | * | |
3097 | * - Within prune_icache() (PF_MEMALLOC == true) | |
3098 | * Here we simply return. We can't afford to block kswapd on the | |
3099 | * journal commit. | |
3100 | * | |
3101 | * In all cases it is actually safe for us to return without doing anything, | |
3102 | * because the inode has been copied into a raw inode buffer in | |
3103 | * ext3_mark_inode_dirty(). This is a correctness thing for O_SYNC and for | |
3104 | * knfsd. | |
3105 | * | |
3106 | * Note that we are absolutely dependent upon all inode dirtiers doing the | |
3107 | * right thing: they *must* call mark_inode_dirty() after dirtying info in | |
3108 | * which we are interested. | |
3109 | * | |
3110 | * It would be a bug for them to not do this. The code: | |
3111 | * | |
3112 | * mark_inode_dirty(inode) | |
3113 | * stuff(); | |
3114 | * inode->i_size = expr; | |
3115 | * | |
3116 | * is in error because a kswapd-driven write_inode() could occur while | |
3117 | * `stuff()' is running, and the new i_size will be lost. Plus the inode | |
3118 | * will no longer be on the superblock's dirty inode list. | |
3119 | */ | |
a9185b41 | 3120 | int ext3_write_inode(struct inode *inode, struct writeback_control *wbc) |
1da177e4 LT |
3121 | { |
3122 | if (current->flags & PF_MEMALLOC) | |
3123 | return 0; | |
3124 | ||
3125 | if (ext3_journal_current_handle()) { | |
9ad163ae | 3126 | jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n"); |
1da177e4 LT |
3127 | dump_stack(); |
3128 | return -EIO; | |
3129 | } | |
3130 | ||
a9185b41 | 3131 | if (wbc->sync_mode != WB_SYNC_ALL) |
1da177e4 LT |
3132 | return 0; |
3133 | ||
3134 | return ext3_force_commit(inode->i_sb); | |
3135 | } | |
3136 | ||
3137 | /* | |
3138 | * ext3_setattr() | |
3139 | * | |
3140 | * Called from notify_change. | |
3141 | * | |
3142 | * We want to trap VFS attempts to truncate the file as soon as | |
3143 | * possible. In particular, we want to make sure that when the VFS | |
3144 | * shrinks i_size, we put the inode on the orphan list and modify | |
3145 | * i_disksize immediately, so that during the subsequent flushing of | |
3146 | * dirty pages and freeing of disk blocks, we can guarantee that any | |
3147 | * commit will leave the blocks being flushed in an unused state on | |
3148 | * disk. (On recovery, the inode will get truncated and the blocks will | |
3149 | * be freed, so we have a strong guarantee that no future commit will | |
ae6ddcc5 | 3150 | * leave these blocks visible to the user.) |
1da177e4 LT |
3151 | * |
3152 | * Called with inode->sem down. | |
3153 | */ | |
3154 | int ext3_setattr(struct dentry *dentry, struct iattr *attr) | |
3155 | { | |
3156 | struct inode *inode = dentry->d_inode; | |
3157 | int error, rc = 0; | |
3158 | const unsigned int ia_valid = attr->ia_valid; | |
3159 | ||
3160 | error = inode_change_ok(inode, attr); | |
3161 | if (error) | |
3162 | return error; | |
3163 | ||
12755627 | 3164 | if (is_quota_modification(inode, attr)) |
871a2931 | 3165 | dquot_initialize(inode); |
1da177e4 LT |
3166 | if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || |
3167 | (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) { | |
3168 | handle_t *handle; | |
3169 | ||
3170 | /* (user+group)*(old+new) structure, inode write (sb, | |
3171 | * inode block, ? - but truncate inode update has it) */ | |
c459001f DM |
3172 | handle = ext3_journal_start(inode, EXT3_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+ |
3173 | EXT3_MAXQUOTAS_DEL_BLOCKS(inode->i_sb)+3); | |
1da177e4 LT |
3174 | if (IS_ERR(handle)) { |
3175 | error = PTR_ERR(handle); | |
3176 | goto err_out; | |
3177 | } | |
b43fa828 | 3178 | error = dquot_transfer(inode, attr); |
1da177e4 LT |
3179 | if (error) { |
3180 | ext3_journal_stop(handle); | |
3181 | return error; | |
3182 | } | |
3183 | /* Update corresponding info in inode so that everything is in | |
3184 | * one transaction */ | |
3185 | if (attr->ia_valid & ATTR_UID) | |
3186 | inode->i_uid = attr->ia_uid; | |
3187 | if (attr->ia_valid & ATTR_GID) | |
3188 | inode->i_gid = attr->ia_gid; | |
3189 | error = ext3_mark_inode_dirty(handle, inode); | |
3190 | ext3_journal_stop(handle); | |
3191 | } | |
3192 | ||
3193 | if (S_ISREG(inode->i_mode) && | |
3194 | attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { | |
3195 | handle_t *handle; | |
3196 | ||
3197 | handle = ext3_journal_start(inode, 3); | |
3198 | if (IS_ERR(handle)) { | |
3199 | error = PTR_ERR(handle); | |
3200 | goto err_out; | |
3201 | } | |
3202 | ||
3203 | error = ext3_orphan_add(handle, inode); | |
3204 | EXT3_I(inode)->i_disksize = attr->ia_size; | |
3205 | rc = ext3_mark_inode_dirty(handle, inode); | |
3206 | if (!error) | |
3207 | error = rc; | |
3208 | ext3_journal_stop(handle); | |
3209 | } | |
3210 | ||
1025774c CH |
3211 | if ((attr->ia_valid & ATTR_SIZE) && |
3212 | attr->ia_size != i_size_read(inode)) { | |
3213 | rc = vmtruncate(inode, attr->ia_size); | |
3214 | if (rc) | |
3215 | goto err_out; | |
3216 | } | |
3217 | ||
3218 | setattr_copy(inode, attr); | |
3219 | mark_inode_dirty(inode); | |
1da177e4 | 3220 | |
1025774c | 3221 | if (ia_valid & ATTR_MODE) |
1da177e4 LT |
3222 | rc = ext3_acl_chmod(inode); |
3223 | ||
3224 | err_out: | |
3225 | ext3_std_error(inode->i_sb, error); | |
3226 | if (!error) | |
3227 | error = rc; | |
3228 | return error; | |
3229 | } | |
3230 | ||
3231 | ||
3232 | /* | |
d6859bfc | 3233 | * How many blocks doth make a writepage()? |
1da177e4 LT |
3234 | * |
3235 | * With N blocks per page, it may be: | |
3236 | * N data blocks | |
3237 | * 2 indirect block | |
3238 | * 2 dindirect | |
3239 | * 1 tindirect | |
3240 | * N+5 bitmap blocks (from the above) | |
3241 | * N+5 group descriptor summary blocks | |
3242 | * 1 inode block | |
3243 | * 1 superblock. | |
3244 | * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files | |
3245 | * | |
3246 | * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS | |
3247 | * | |
3248 | * With ordered or writeback data it's the same, less the N data blocks. | |
3249 | * | |
3250 | * If the inode's direct blocks can hold an integral number of pages then a | |
3251 | * page cannot straddle two indirect blocks, and we can only touch one indirect | |
3252 | * and dindirect block, and the "5" above becomes "3". | |
3253 | * | |
3254 | * This still overestimates under most circumstances. If we were to pass the | |
3255 | * start and end offsets in here as well we could do block_to_path() on each | |
3256 | * block and work out the exact number of indirects which are touched. Pah. | |
3257 | */ | |
3258 | ||
3259 | static int ext3_writepage_trans_blocks(struct inode *inode) | |
3260 | { | |
3261 | int bpp = ext3_journal_blocks_per_page(inode); | |
3262 | int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3; | |
3263 | int ret; | |
3264 | ||
3265 | if (ext3_should_journal_data(inode)) | |
3266 | ret = 3 * (bpp + indirects) + 2; | |
3267 | else | |
3268 | ret = 2 * (bpp + indirects) + 2; | |
3269 | ||
3270 | #ifdef CONFIG_QUOTA | |
871a2931 | 3271 | /* We know that structure was already allocated during dquot_initialize so |
1da177e4 | 3272 | * we will be updating only the data blocks + inodes */ |
c459001f | 3273 | ret += EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb); |
1da177e4 LT |
3274 | #endif |
3275 | ||
3276 | return ret; | |
3277 | } | |
3278 | ||
3279 | /* | |
3280 | * The caller must have previously called ext3_reserve_inode_write(). | |
3281 | * Give this, we know that the caller already has write access to iloc->bh. | |
3282 | */ | |
3283 | int ext3_mark_iloc_dirty(handle_t *handle, | |
3284 | struct inode *inode, struct ext3_iloc *iloc) | |
3285 | { | |
3286 | int err = 0; | |
3287 | ||
3288 | /* the do_update_inode consumes one bh->b_count */ | |
3289 | get_bh(iloc->bh); | |
3290 | ||
3291 | /* ext3_do_update_inode() does journal_dirty_metadata */ | |
3292 | err = ext3_do_update_inode(handle, inode, iloc); | |
3293 | put_bh(iloc->bh); | |
3294 | return err; | |
3295 | } | |
3296 | ||
ae6ddcc5 | 3297 | /* |
1da177e4 | 3298 | * On success, We end up with an outstanding reference count against |
ae6ddcc5 | 3299 | * iloc->bh. This _must_ be cleaned up later. |
1da177e4 LT |
3300 | */ |
3301 | ||
3302 | int | |
ae6ddcc5 | 3303 | ext3_reserve_inode_write(handle_t *handle, struct inode *inode, |
1da177e4 LT |
3304 | struct ext3_iloc *iloc) |
3305 | { | |
3306 | int err = 0; | |
3307 | if (handle) { | |
3308 | err = ext3_get_inode_loc(inode, iloc); | |
3309 | if (!err) { | |
3310 | BUFFER_TRACE(iloc->bh, "get_write_access"); | |
3311 | err = ext3_journal_get_write_access(handle, iloc->bh); | |
3312 | if (err) { | |
3313 | brelse(iloc->bh); | |
3314 | iloc->bh = NULL; | |
3315 | } | |
3316 | } | |
3317 | } | |
3318 | ext3_std_error(inode->i_sb, err); | |
3319 | return err; | |
3320 | } | |
3321 | ||
3322 | /* | |
d6859bfc AM |
3323 | * What we do here is to mark the in-core inode as clean with respect to inode |
3324 | * dirtiness (it may still be data-dirty). | |
1da177e4 LT |
3325 | * This means that the in-core inode may be reaped by prune_icache |
3326 | * without having to perform any I/O. This is a very good thing, | |
3327 | * because *any* task may call prune_icache - even ones which | |
3328 | * have a transaction open against a different journal. | |
3329 | * | |
3330 | * Is this cheating? Not really. Sure, we haven't written the | |
3331 | * inode out, but prune_icache isn't a user-visible syncing function. | |
3332 | * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) | |
3333 | * we start and wait on commits. | |
3334 | * | |
3335 | * Is this efficient/effective? Well, we're being nice to the system | |
3336 | * by cleaning up our inodes proactively so they can be reaped | |
3337 | * without I/O. But we are potentially leaving up to five seconds' | |
3338 | * worth of inodes floating about which prune_icache wants us to | |
3339 | * write out. One way to fix that would be to get prune_icache() | |
3340 | * to do a write_super() to free up some memory. It has the desired | |
3341 | * effect. | |
3342 | */ | |
3343 | int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode) | |
3344 | { | |
3345 | struct ext3_iloc iloc; | |
3346 | int err; | |
3347 | ||
3348 | might_sleep(); | |
3349 | err = ext3_reserve_inode_write(handle, inode, &iloc); | |
3350 | if (!err) | |
3351 | err = ext3_mark_iloc_dirty(handle, inode, &iloc); | |
3352 | return err; | |
3353 | } | |
3354 | ||
3355 | /* | |
d6859bfc | 3356 | * ext3_dirty_inode() is called from __mark_inode_dirty() |
1da177e4 LT |
3357 | * |
3358 | * We're really interested in the case where a file is being extended. | |
3359 | * i_size has been changed by generic_commit_write() and we thus need | |
3360 | * to include the updated inode in the current transaction. | |
3361 | * | |
5dd4056d | 3362 | * Also, dquot_alloc_space() will always dirty the inode when blocks |
1da177e4 LT |
3363 | * are allocated to the file. |
3364 | * | |
3365 | * If the inode is marked synchronous, we don't honour that here - doing | |
3366 | * so would cause a commit on atime updates, which we don't bother doing. | |
3367 | * We handle synchronous inodes at the highest possible level. | |
3368 | */ | |
3369 | void ext3_dirty_inode(struct inode *inode) | |
3370 | { | |
3371 | handle_t *current_handle = ext3_journal_current_handle(); | |
3372 | handle_t *handle; | |
3373 | ||
3374 | handle = ext3_journal_start(inode, 2); | |
3375 | if (IS_ERR(handle)) | |
3376 | goto out; | |
3377 | if (current_handle && | |
3378 | current_handle->h_transaction != handle->h_transaction) { | |
3379 | /* This task has a transaction open against a different fs */ | |
3380 | printk(KERN_EMERG "%s: transactions do not match!\n", | |
e05b6b52 | 3381 | __func__); |
1da177e4 LT |
3382 | } else { |
3383 | jbd_debug(5, "marking dirty. outer handle=%p\n", | |
3384 | current_handle); | |
3385 | ext3_mark_inode_dirty(handle, inode); | |
3386 | } | |
3387 | ext3_journal_stop(handle); | |
3388 | out: | |
3389 | return; | |
3390 | } | |
3391 | ||
d6859bfc | 3392 | #if 0 |
ae6ddcc5 | 3393 | /* |
1da177e4 LT |
3394 | * Bind an inode's backing buffer_head into this transaction, to prevent |
3395 | * it from being flushed to disk early. Unlike | |
3396 | * ext3_reserve_inode_write, this leaves behind no bh reference and | |
3397 | * returns no iloc structure, so the caller needs to repeat the iloc | |
3398 | * lookup to mark the inode dirty later. | |
3399 | */ | |
d6859bfc | 3400 | static int ext3_pin_inode(handle_t *handle, struct inode *inode) |
1da177e4 LT |
3401 | { |
3402 | struct ext3_iloc iloc; | |
3403 | ||
3404 | int err = 0; | |
3405 | if (handle) { | |
3406 | err = ext3_get_inode_loc(inode, &iloc); | |
3407 | if (!err) { | |
3408 | BUFFER_TRACE(iloc.bh, "get_write_access"); | |
3409 | err = journal_get_write_access(handle, iloc.bh); | |
3410 | if (!err) | |
ae6ddcc5 | 3411 | err = ext3_journal_dirty_metadata(handle, |
1da177e4 LT |
3412 | iloc.bh); |
3413 | brelse(iloc.bh); | |
3414 | } | |
3415 | } | |
3416 | ext3_std_error(inode->i_sb, err); | |
3417 | return err; | |
3418 | } | |
3419 | #endif | |
3420 | ||
3421 | int ext3_change_inode_journal_flag(struct inode *inode, int val) | |
3422 | { | |
3423 | journal_t *journal; | |
3424 | handle_t *handle; | |
3425 | int err; | |
3426 | ||
3427 | /* | |
3428 | * We have to be very careful here: changing a data block's | |
3429 | * journaling status dynamically is dangerous. If we write a | |
3430 | * data block to the journal, change the status and then delete | |
3431 | * that block, we risk forgetting to revoke the old log record | |
3432 | * from the journal and so a subsequent replay can corrupt data. | |
3433 | * So, first we make sure that the journal is empty and that | |
3434 | * nobody is changing anything. | |
3435 | */ | |
3436 | ||
3437 | journal = EXT3_JOURNAL(inode); | |
e3a68e30 | 3438 | if (is_journal_aborted(journal)) |
1da177e4 LT |
3439 | return -EROFS; |
3440 | ||
3441 | journal_lock_updates(journal); | |
3442 | journal_flush(journal); | |
3443 | ||
3444 | /* | |
3445 | * OK, there are no updates running now, and all cached data is | |
3446 | * synced to disk. We are now in a completely consistent state | |
3447 | * which doesn't have anything in the journal, and we know that | |
3448 | * no filesystem updates are running, so it is safe to modify | |
3449 | * the inode's in-core data-journaling state flag now. | |
3450 | */ | |
3451 | ||
3452 | if (val) | |
3453 | EXT3_I(inode)->i_flags |= EXT3_JOURNAL_DATA_FL; | |
3454 | else | |
3455 | EXT3_I(inode)->i_flags &= ~EXT3_JOURNAL_DATA_FL; | |
3456 | ext3_set_aops(inode); | |
3457 | ||
3458 | journal_unlock_updates(journal); | |
3459 | ||
3460 | /* Finally we can mark the inode as dirty. */ | |
3461 | ||
3462 | handle = ext3_journal_start(inode, 1); | |
3463 | if (IS_ERR(handle)) | |
3464 | return PTR_ERR(handle); | |
3465 | ||
3466 | err = ext3_mark_inode_dirty(handle, inode); | |
3467 | handle->h_sync = 1; | |
3468 | ext3_journal_stop(handle); | |
3469 | ext3_std_error(inode->i_sb, err); | |
3470 | ||
3471 | return err; | |
3472 | } |