Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/ext3/inode.c | |
3 | * | |
4 | * Copyright (C) 1992, 1993, 1994, 1995 | |
5 | * Remy Card (card@masi.ibp.fr) | |
6 | * Laboratoire MASI - Institut Blaise Pascal | |
7 | * Universite Pierre et Marie Curie (Paris VI) | |
8 | * | |
9 | * from | |
10 | * | |
11 | * linux/fs/minix/inode.c | |
12 | * | |
13 | * Copyright (C) 1991, 1992 Linus Torvalds | |
14 | * | |
15 | * Goal-directed block allocation by Stephen Tweedie | |
e9ad5620 | 16 | * (sct@redhat.com), 1993, 1998 |
1da177e4 LT |
17 | * Big-endian to little-endian byte-swapping/bitmaps by |
18 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
19 | * 64-bit file support on 64-bit platforms by Jakub Jelinek | |
e9ad5620 | 20 | * (jj@sunsite.ms.mff.cuni.cz) |
1da177e4 LT |
21 | * |
22 | * Assorted race fixes, rewrite of ext3_get_block() by Al Viro, 2000 | |
23 | */ | |
24 | ||
25 | #include <linux/module.h> | |
26 | #include <linux/fs.h> | |
27 | #include <linux/time.h> | |
28 | #include <linux/ext3_jbd.h> | |
29 | #include <linux/jbd.h> | |
1da177e4 LT |
30 | #include <linux/highuid.h> |
31 | #include <linux/pagemap.h> | |
32 | #include <linux/quotaops.h> | |
33 | #include <linux/string.h> | |
34 | #include <linux/buffer_head.h> | |
35 | #include <linux/writeback.h> | |
36 | #include <linux/mpage.h> | |
37 | #include <linux/uio.h> | |
caa38fb0 | 38 | #include <linux/bio.h> |
1da177e4 LT |
39 | #include "xattr.h" |
40 | #include "acl.h" | |
41 | ||
42 | static int ext3_writepage_trans_blocks(struct inode *inode); | |
43 | ||
44 | /* | |
45 | * Test whether an inode is a fast symlink. | |
46 | */ | |
d6859bfc | 47 | static int ext3_inode_is_fast_symlink(struct inode *inode) |
1da177e4 LT |
48 | { |
49 | int ea_blocks = EXT3_I(inode)->i_file_acl ? | |
50 | (inode->i_sb->s_blocksize >> 9) : 0; | |
51 | ||
d6859bfc | 52 | return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); |
1da177e4 LT |
53 | } |
54 | ||
d6859bfc AM |
55 | /* |
56 | * The ext3 forget function must perform a revoke if we are freeing data | |
1da177e4 | 57 | * which has been journaled. Metadata (eg. indirect blocks) must be |
ae6ddcc5 | 58 | * revoked in all cases. |
1da177e4 LT |
59 | * |
60 | * "bh" may be NULL: a metadata block may have been freed from memory | |
61 | * but there may still be a record of it in the journal, and that record | |
62 | * still needs to be revoked. | |
63 | */ | |
d6859bfc | 64 | int ext3_forget(handle_t *handle, int is_metadata, struct inode *inode, |
1c2bf374 | 65 | struct buffer_head *bh, ext3_fsblk_t blocknr) |
1da177e4 LT |
66 | { |
67 | int err; | |
68 | ||
69 | might_sleep(); | |
70 | ||
71 | BUFFER_TRACE(bh, "enter"); | |
72 | ||
73 | jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " | |
74 | "data mode %lx\n", | |
75 | bh, is_metadata, inode->i_mode, | |
76 | test_opt(inode->i_sb, DATA_FLAGS)); | |
77 | ||
78 | /* Never use the revoke function if we are doing full data | |
79 | * journaling: there is no need to, and a V1 superblock won't | |
80 | * support it. Otherwise, only skip the revoke on un-journaled | |
81 | * data blocks. */ | |
82 | ||
83 | if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA || | |
84 | (!is_metadata && !ext3_should_journal_data(inode))) { | |
85 | if (bh) { | |
86 | BUFFER_TRACE(bh, "call journal_forget"); | |
87 | return ext3_journal_forget(handle, bh); | |
88 | } | |
89 | return 0; | |
90 | } | |
91 | ||
92 | /* | |
93 | * data!=journal && (is_metadata || should_journal_data(inode)) | |
94 | */ | |
95 | BUFFER_TRACE(bh, "call ext3_journal_revoke"); | |
96 | err = ext3_journal_revoke(handle, blocknr, bh); | |
97 | if (err) | |
98 | ext3_abort(inode->i_sb, __FUNCTION__, | |
99 | "error %d when attempting revoke", err); | |
100 | BUFFER_TRACE(bh, "exit"); | |
101 | return err; | |
102 | } | |
103 | ||
104 | /* | |
d6859bfc | 105 | * Work out how many blocks we need to proceed with the next chunk of a |
1da177e4 LT |
106 | * truncate transaction. |
107 | */ | |
ae6ddcc5 | 108 | static unsigned long blocks_for_truncate(struct inode *inode) |
1da177e4 LT |
109 | { |
110 | unsigned long needed; | |
111 | ||
112 | needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); | |
113 | ||
114 | /* Give ourselves just enough room to cope with inodes in which | |
115 | * i_blocks is corrupt: we've seen disk corruptions in the past | |
116 | * which resulted in random data in an inode which looked enough | |
117 | * like a regular file for ext3 to try to delete it. Things | |
118 | * will go a bit crazy if that happens, but at least we should | |
119 | * try not to panic the whole kernel. */ | |
120 | if (needed < 2) | |
121 | needed = 2; | |
122 | ||
123 | /* But we need to bound the transaction so we don't overflow the | |
124 | * journal. */ | |
ae6ddcc5 | 125 | if (needed > EXT3_MAX_TRANS_DATA) |
1da177e4 LT |
126 | needed = EXT3_MAX_TRANS_DATA; |
127 | ||
1f54587b | 128 | return EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + needed; |
1da177e4 LT |
129 | } |
130 | ||
ae6ddcc5 | 131 | /* |
1da177e4 LT |
132 | * Truncate transactions can be complex and absolutely huge. So we need to |
133 | * be able to restart the transaction at a conventient checkpoint to make | |
134 | * sure we don't overflow the journal. | |
135 | * | |
136 | * start_transaction gets us a new handle for a truncate transaction, | |
137 | * and extend_transaction tries to extend the existing one a bit. If | |
138 | * extend fails, we need to propagate the failure up and restart the | |
ae6ddcc5 | 139 | * transaction in the top-level truncate loop. --sct |
1da177e4 | 140 | */ |
ae6ddcc5 | 141 | static handle_t *start_transaction(struct inode *inode) |
1da177e4 LT |
142 | { |
143 | handle_t *result; | |
144 | ||
145 | result = ext3_journal_start(inode, blocks_for_truncate(inode)); | |
146 | if (!IS_ERR(result)) | |
147 | return result; | |
148 | ||
149 | ext3_std_error(inode->i_sb, PTR_ERR(result)); | |
150 | return result; | |
151 | } | |
152 | ||
153 | /* | |
154 | * Try to extend this transaction for the purposes of truncation. | |
155 | * | |
156 | * Returns 0 if we managed to create more room. If we can't create more | |
157 | * room, and the transaction must be restarted we return 1. | |
158 | */ | |
159 | static int try_to_extend_transaction(handle_t *handle, struct inode *inode) | |
160 | { | |
161 | if (handle->h_buffer_credits > EXT3_RESERVE_TRANS_BLOCKS) | |
162 | return 0; | |
163 | if (!ext3_journal_extend(handle, blocks_for_truncate(inode))) | |
164 | return 0; | |
165 | return 1; | |
166 | } | |
167 | ||
168 | /* | |
169 | * Restart the transaction associated with *handle. This does a commit, | |
170 | * so before we call here everything must be consistently dirtied against | |
171 | * this transaction. | |
172 | */ | |
173 | static int ext3_journal_test_restart(handle_t *handle, struct inode *inode) | |
174 | { | |
175 | jbd_debug(2, "restarting handle %p\n", handle); | |
176 | return ext3_journal_restart(handle, blocks_for_truncate(inode)); | |
177 | } | |
178 | ||
179 | /* | |
180 | * Called at the last iput() if i_nlink is zero. | |
181 | */ | |
182 | void ext3_delete_inode (struct inode * inode) | |
183 | { | |
184 | handle_t *handle; | |
185 | ||
fef26658 MF |
186 | truncate_inode_pages(&inode->i_data, 0); |
187 | ||
1da177e4 LT |
188 | if (is_bad_inode(inode)) |
189 | goto no_delete; | |
190 | ||
191 | handle = start_transaction(inode); | |
192 | if (IS_ERR(handle)) { | |
d6859bfc AM |
193 | /* |
194 | * If we're going to skip the normal cleanup, we still need to | |
195 | * make sure that the in-core orphan linked list is properly | |
196 | * cleaned up. | |
197 | */ | |
1da177e4 LT |
198 | ext3_orphan_del(NULL, inode); |
199 | goto no_delete; | |
200 | } | |
201 | ||
202 | if (IS_SYNC(inode)) | |
203 | handle->h_sync = 1; | |
204 | inode->i_size = 0; | |
205 | if (inode->i_blocks) | |
206 | ext3_truncate(inode); | |
207 | /* | |
208 | * Kill off the orphan record which ext3_truncate created. | |
209 | * AKPM: I think this can be inside the above `if'. | |
210 | * Note that ext3_orphan_del() has to be able to cope with the | |
211 | * deletion of a non-existent orphan - this is because we don't | |
212 | * know if ext3_truncate() actually created an orphan record. | |
213 | * (Well, we could do this if we need to, but heck - it works) | |
214 | */ | |
215 | ext3_orphan_del(handle, inode); | |
216 | EXT3_I(inode)->i_dtime = get_seconds(); | |
217 | ||
ae6ddcc5 | 218 | /* |
1da177e4 LT |
219 | * One subtle ordering requirement: if anything has gone wrong |
220 | * (transaction abort, IO errors, whatever), then we can still | |
221 | * do these next steps (the fs will already have been marked as | |
222 | * having errors), but we can't free the inode if the mark_dirty | |
ae6ddcc5 | 223 | * fails. |
1da177e4 LT |
224 | */ |
225 | if (ext3_mark_inode_dirty(handle, inode)) | |
226 | /* If that failed, just do the required in-core inode clear. */ | |
227 | clear_inode(inode); | |
228 | else | |
229 | ext3_free_inode(handle, inode); | |
230 | ext3_journal_stop(handle); | |
231 | return; | |
232 | no_delete: | |
233 | clear_inode(inode); /* We must guarantee clearing of inode... */ | |
234 | } | |
235 | ||
1da177e4 LT |
236 | typedef struct { |
237 | __le32 *p; | |
238 | __le32 key; | |
239 | struct buffer_head *bh; | |
240 | } Indirect; | |
241 | ||
242 | static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) | |
243 | { | |
244 | p->key = *(p->p = v); | |
245 | p->bh = bh; | |
246 | } | |
247 | ||
d6859bfc | 248 | static int verify_chain(Indirect *from, Indirect *to) |
1da177e4 LT |
249 | { |
250 | while (from <= to && from->key == *from->p) | |
251 | from++; | |
252 | return (from > to); | |
253 | } | |
254 | ||
255 | /** | |
256 | * ext3_block_to_path - parse the block number into array of offsets | |
257 | * @inode: inode in question (we are only interested in its superblock) | |
258 | * @i_block: block number to be parsed | |
259 | * @offsets: array to store the offsets in | |
260 | * @boundary: set this non-zero if the referred-to block is likely to be | |
261 | * followed (on disk) by an indirect block. | |
262 | * | |
263 | * To store the locations of file's data ext3 uses a data structure common | |
264 | * for UNIX filesystems - tree of pointers anchored in the inode, with | |
265 | * data blocks at leaves and indirect blocks in intermediate nodes. | |
266 | * This function translates the block number into path in that tree - | |
267 | * return value is the path length and @offsets[n] is the offset of | |
268 | * pointer to (n+1)th node in the nth one. If @block is out of range | |
269 | * (negative or too large) warning is printed and zero returned. | |
270 | * | |
271 | * Note: function doesn't find node addresses, so no IO is needed. All | |
272 | * we need to know is the capacity of indirect blocks (taken from the | |
273 | * inode->i_sb). | |
274 | */ | |
275 | ||
276 | /* | |
277 | * Portability note: the last comparison (check that we fit into triple | |
278 | * indirect block) is spelled differently, because otherwise on an | |
279 | * architecture with 32-bit longs and 8Kb pages we might get into trouble | |
280 | * if our filesystem had 8Kb blocks. We might use long long, but that would | |
281 | * kill us on x86. Oh, well, at least the sign propagation does not matter - | |
282 | * i_block would have to be negative in the very beginning, so we would not | |
283 | * get there at all. | |
284 | */ | |
285 | ||
286 | static int ext3_block_to_path(struct inode *inode, | |
287 | long i_block, int offsets[4], int *boundary) | |
288 | { | |
289 | int ptrs = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
290 | int ptrs_bits = EXT3_ADDR_PER_BLOCK_BITS(inode->i_sb); | |
291 | const long direct_blocks = EXT3_NDIR_BLOCKS, | |
292 | indirect_blocks = ptrs, | |
293 | double_blocks = (1 << (ptrs_bits * 2)); | |
294 | int n = 0; | |
295 | int final = 0; | |
296 | ||
297 | if (i_block < 0) { | |
298 | ext3_warning (inode->i_sb, "ext3_block_to_path", "block < 0"); | |
299 | } else if (i_block < direct_blocks) { | |
300 | offsets[n++] = i_block; | |
301 | final = direct_blocks; | |
302 | } else if ( (i_block -= direct_blocks) < indirect_blocks) { | |
303 | offsets[n++] = EXT3_IND_BLOCK; | |
304 | offsets[n++] = i_block; | |
305 | final = ptrs; | |
306 | } else if ((i_block -= indirect_blocks) < double_blocks) { | |
307 | offsets[n++] = EXT3_DIND_BLOCK; | |
308 | offsets[n++] = i_block >> ptrs_bits; | |
309 | offsets[n++] = i_block & (ptrs - 1); | |
310 | final = ptrs; | |
311 | } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { | |
312 | offsets[n++] = EXT3_TIND_BLOCK; | |
313 | offsets[n++] = i_block >> (ptrs_bits * 2); | |
314 | offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); | |
315 | offsets[n++] = i_block & (ptrs - 1); | |
316 | final = ptrs; | |
317 | } else { | |
d6859bfc | 318 | ext3_warning(inode->i_sb, "ext3_block_to_path", "block > big"); |
1da177e4 LT |
319 | } |
320 | if (boundary) | |
89747d36 | 321 | *boundary = final - 1 - (i_block & (ptrs - 1)); |
1da177e4 LT |
322 | return n; |
323 | } | |
324 | ||
325 | /** | |
326 | * ext3_get_branch - read the chain of indirect blocks leading to data | |
327 | * @inode: inode in question | |
328 | * @depth: depth of the chain (1 - direct pointer, etc.) | |
329 | * @offsets: offsets of pointers in inode/indirect blocks | |
330 | * @chain: place to store the result | |
331 | * @err: here we store the error value | |
332 | * | |
333 | * Function fills the array of triples <key, p, bh> and returns %NULL | |
334 | * if everything went OK or the pointer to the last filled triple | |
335 | * (incomplete one) otherwise. Upon the return chain[i].key contains | |
336 | * the number of (i+1)-th block in the chain (as it is stored in memory, | |
337 | * i.e. little-endian 32-bit), chain[i].p contains the address of that | |
338 | * number (it points into struct inode for i==0 and into the bh->b_data | |
339 | * for i>0) and chain[i].bh points to the buffer_head of i-th indirect | |
340 | * block for i>0 and NULL for i==0. In other words, it holds the block | |
341 | * numbers of the chain, addresses they were taken from (and where we can | |
342 | * verify that chain did not change) and buffer_heads hosting these | |
343 | * numbers. | |
344 | * | |
345 | * Function stops when it stumbles upon zero pointer (absent block) | |
346 | * (pointer to last triple returned, *@err == 0) | |
347 | * or when it gets an IO error reading an indirect block | |
348 | * (ditto, *@err == -EIO) | |
349 | * or when it notices that chain had been changed while it was reading | |
350 | * (ditto, *@err == -EAGAIN) | |
351 | * or when it reads all @depth-1 indirect blocks successfully and finds | |
352 | * the whole chain, all way to the data (returns %NULL, *err == 0). | |
353 | */ | |
354 | static Indirect *ext3_get_branch(struct inode *inode, int depth, int *offsets, | |
355 | Indirect chain[4], int *err) | |
356 | { | |
357 | struct super_block *sb = inode->i_sb; | |
358 | Indirect *p = chain; | |
359 | struct buffer_head *bh; | |
360 | ||
361 | *err = 0; | |
362 | /* i_data is not going away, no lock needed */ | |
363 | add_chain (chain, NULL, EXT3_I(inode)->i_data + *offsets); | |
364 | if (!p->key) | |
365 | goto no_block; | |
366 | while (--depth) { | |
367 | bh = sb_bread(sb, le32_to_cpu(p->key)); | |
368 | if (!bh) | |
369 | goto failure; | |
370 | /* Reader: pointers */ | |
371 | if (!verify_chain(chain, p)) | |
372 | goto changed; | |
373 | add_chain(++p, bh, (__le32*)bh->b_data + *++offsets); | |
374 | /* Reader: end */ | |
375 | if (!p->key) | |
376 | goto no_block; | |
377 | } | |
378 | return NULL; | |
379 | ||
380 | changed: | |
381 | brelse(bh); | |
382 | *err = -EAGAIN; | |
383 | goto no_block; | |
384 | failure: | |
385 | *err = -EIO; | |
386 | no_block: | |
387 | return p; | |
388 | } | |
389 | ||
390 | /** | |
391 | * ext3_find_near - find a place for allocation with sufficient locality | |
392 | * @inode: owner | |
393 | * @ind: descriptor of indirect block. | |
394 | * | |
395 | * This function returns the prefered place for block allocation. | |
396 | * It is used when heuristic for sequential allocation fails. | |
397 | * Rules are: | |
398 | * + if there is a block to the left of our position - allocate near it. | |
399 | * + if pointer will live in indirect block - allocate near that block. | |
400 | * + if pointer will live in inode - allocate in the same | |
ae6ddcc5 | 401 | * cylinder group. |
1da177e4 LT |
402 | * |
403 | * In the latter case we colour the starting block by the callers PID to | |
404 | * prevent it from clashing with concurrent allocations for a different inode | |
405 | * in the same block group. The PID is used here so that functionally related | |
406 | * files will be close-by on-disk. | |
407 | * | |
408 | * Caller must make sure that @ind is valid and will stay that way. | |
409 | */ | |
43d23f90 | 410 | static ext3_fsblk_t ext3_find_near(struct inode *inode, Indirect *ind) |
1da177e4 LT |
411 | { |
412 | struct ext3_inode_info *ei = EXT3_I(inode); | |
413 | __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data; | |
414 | __le32 *p; | |
43d23f90 MC |
415 | ext3_fsblk_t bg_start; |
416 | ext3_grpblk_t colour; | |
1da177e4 LT |
417 | |
418 | /* Try to find previous block */ | |
d6859bfc | 419 | for (p = ind->p - 1; p >= start; p--) { |
1da177e4 LT |
420 | if (*p) |
421 | return le32_to_cpu(*p); | |
d6859bfc | 422 | } |
1da177e4 LT |
423 | |
424 | /* No such thing, so let's try location of indirect block */ | |
425 | if (ind->bh) | |
426 | return ind->bh->b_blocknr; | |
427 | ||
428 | /* | |
d6859bfc AM |
429 | * It is going to be referred to from the inode itself? OK, just put it |
430 | * into the same cylinder group then. | |
1da177e4 | 431 | */ |
43d23f90 | 432 | bg_start = ext3_group_first_block_no(inode->i_sb, ei->i_block_group); |
1da177e4 LT |
433 | colour = (current->pid % 16) * |
434 | (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16); | |
435 | return bg_start + colour; | |
436 | } | |
437 | ||
438 | /** | |
439 | * ext3_find_goal - find a prefered place for allocation. | |
440 | * @inode: owner | |
441 | * @block: block we want | |
442 | * @chain: chain of indirect blocks | |
443 | * @partial: pointer to the last triple within a chain | |
444 | * @goal: place to store the result. | |
445 | * | |
446 | * Normally this function find the prefered place for block allocation, | |
fe55c452 | 447 | * stores it in *@goal and returns zero. |
1da177e4 LT |
448 | */ |
449 | ||
43d23f90 | 450 | static ext3_fsblk_t ext3_find_goal(struct inode *inode, long block, |
fe55c452 | 451 | Indirect chain[4], Indirect *partial) |
1da177e4 | 452 | { |
d6859bfc AM |
453 | struct ext3_block_alloc_info *block_i; |
454 | ||
455 | block_i = EXT3_I(inode)->i_block_alloc_info; | |
1da177e4 LT |
456 | |
457 | /* | |
458 | * try the heuristic for sequential allocation, | |
459 | * failing that at least try to get decent locality. | |
460 | */ | |
461 | if (block_i && (block == block_i->last_alloc_logical_block + 1) | |
462 | && (block_i->last_alloc_physical_block != 0)) { | |
fe55c452 | 463 | return block_i->last_alloc_physical_block + 1; |
1da177e4 LT |
464 | } |
465 | ||
fe55c452 | 466 | return ext3_find_near(inode, partial); |
1da177e4 | 467 | } |
d6859bfc | 468 | |
b47b2478 MC |
469 | /** |
470 | * ext3_blks_to_allocate: Look up the block map and count the number | |
471 | * of direct blocks need to be allocated for the given branch. | |
472 | * | |
e9ad5620 | 473 | * @branch: chain of indirect blocks |
b47b2478 MC |
474 | * @k: number of blocks need for indirect blocks |
475 | * @blks: number of data blocks to be mapped. | |
476 | * @blocks_to_boundary: the offset in the indirect block | |
477 | * | |
478 | * return the total number of blocks to be allocate, including the | |
479 | * direct and indirect blocks. | |
480 | */ | |
d6859bfc | 481 | static int ext3_blks_to_allocate(Indirect *branch, int k, unsigned long blks, |
b47b2478 MC |
482 | int blocks_to_boundary) |
483 | { | |
484 | unsigned long count = 0; | |
485 | ||
486 | /* | |
487 | * Simple case, [t,d]Indirect block(s) has not allocated yet | |
488 | * then it's clear blocks on that path have not allocated | |
489 | */ | |
490 | if (k > 0) { | |
d6859bfc | 491 | /* right now we don't handle cross boundary allocation */ |
b47b2478 MC |
492 | if (blks < blocks_to_boundary + 1) |
493 | count += blks; | |
494 | else | |
495 | count += blocks_to_boundary + 1; | |
496 | return count; | |
497 | } | |
498 | ||
499 | count++; | |
500 | while (count < blks && count <= blocks_to_boundary && | |
501 | le32_to_cpu(*(branch[0].p + count)) == 0) { | |
502 | count++; | |
503 | } | |
504 | return count; | |
505 | } | |
506 | ||
507 | /** | |
508 | * ext3_alloc_blocks: multiple allocate blocks needed for a branch | |
509 | * @indirect_blks: the number of blocks need to allocate for indirect | |
510 | * blocks | |
511 | * | |
512 | * @new_blocks: on return it will store the new block numbers for | |
513 | * the indirect blocks(if needed) and the first direct block, | |
514 | * @blks: on return it will store the total number of allocated | |
515 | * direct blocks | |
516 | */ | |
517 | static int ext3_alloc_blocks(handle_t *handle, struct inode *inode, | |
43d23f90 MC |
518 | ext3_fsblk_t goal, int indirect_blks, int blks, |
519 | ext3_fsblk_t new_blocks[4], int *err) | |
b47b2478 MC |
520 | { |
521 | int target, i; | |
522 | unsigned long count = 0; | |
523 | int index = 0; | |
43d23f90 | 524 | ext3_fsblk_t current_block = 0; |
b47b2478 MC |
525 | int ret = 0; |
526 | ||
527 | /* | |
528 | * Here we try to allocate the requested multiple blocks at once, | |
529 | * on a best-effort basis. | |
530 | * To build a branch, we should allocate blocks for | |
531 | * the indirect blocks(if not allocated yet), and at least | |
532 | * the first direct block of this branch. That's the | |
533 | * minimum number of blocks need to allocate(required) | |
534 | */ | |
535 | target = blks + indirect_blks; | |
536 | ||
537 | while (1) { | |
538 | count = target; | |
539 | /* allocating blocks for indirect blocks and direct blocks */ | |
d6859bfc | 540 | current_block = ext3_new_blocks(handle,inode,goal,&count,err); |
b47b2478 MC |
541 | if (*err) |
542 | goto failed_out; | |
543 | ||
544 | target -= count; | |
545 | /* allocate blocks for indirect blocks */ | |
546 | while (index < indirect_blks && count) { | |
547 | new_blocks[index++] = current_block++; | |
548 | count--; | |
549 | } | |
550 | ||
551 | if (count > 0) | |
552 | break; | |
553 | } | |
554 | ||
555 | /* save the new block number for the first direct block */ | |
556 | new_blocks[index] = current_block; | |
557 | ||
558 | /* total number of blocks allocated for direct blocks */ | |
559 | ret = count; | |
560 | *err = 0; | |
561 | return ret; | |
562 | failed_out: | |
563 | for (i = 0; i <index; i++) | |
564 | ext3_free_blocks(handle, inode, new_blocks[i], 1); | |
565 | return ret; | |
566 | } | |
1da177e4 LT |
567 | |
568 | /** | |
569 | * ext3_alloc_branch - allocate and set up a chain of blocks. | |
570 | * @inode: owner | |
b47b2478 MC |
571 | * @indirect_blks: number of allocated indirect blocks |
572 | * @blks: number of allocated direct blocks | |
1da177e4 LT |
573 | * @offsets: offsets (in the blocks) to store the pointers to next. |
574 | * @branch: place to store the chain in. | |
575 | * | |
b47b2478 | 576 | * This function allocates blocks, zeroes out all but the last one, |
1da177e4 LT |
577 | * links them into chain and (if we are synchronous) writes them to disk. |
578 | * In other words, it prepares a branch that can be spliced onto the | |
579 | * inode. It stores the information about that chain in the branch[], in | |
580 | * the same format as ext3_get_branch() would do. We are calling it after | |
581 | * we had read the existing part of chain and partial points to the last | |
582 | * triple of that (one with zero ->key). Upon the exit we have the same | |
5b116879 | 583 | * picture as after the successful ext3_get_block(), except that in one |
1da177e4 LT |
584 | * place chain is disconnected - *branch->p is still zero (we did not |
585 | * set the last link), but branch->key contains the number that should | |
586 | * be placed into *branch->p to fill that gap. | |
587 | * | |
588 | * If allocation fails we free all blocks we've allocated (and forget | |
589 | * their buffer_heads) and return the error value the from failed | |
590 | * ext3_alloc_block() (normally -ENOSPC). Otherwise we set the chain | |
591 | * as described above and return 0. | |
592 | */ | |
1da177e4 | 593 | static int ext3_alloc_branch(handle_t *handle, struct inode *inode, |
43d23f90 | 594 | int indirect_blks, int *blks, ext3_fsblk_t goal, |
b47b2478 | 595 | int *offsets, Indirect *branch) |
1da177e4 LT |
596 | { |
597 | int blocksize = inode->i_sb->s_blocksize; | |
b47b2478 | 598 | int i, n = 0; |
1da177e4 | 599 | int err = 0; |
b47b2478 MC |
600 | struct buffer_head *bh; |
601 | int num; | |
43d23f90 MC |
602 | ext3_fsblk_t new_blocks[4]; |
603 | ext3_fsblk_t current_block; | |
1da177e4 | 604 | |
b47b2478 MC |
605 | num = ext3_alloc_blocks(handle, inode, goal, indirect_blks, |
606 | *blks, new_blocks, &err); | |
607 | if (err) | |
608 | return err; | |
1da177e4 | 609 | |
b47b2478 MC |
610 | branch[0].key = cpu_to_le32(new_blocks[0]); |
611 | /* | |
612 | * metadata blocks and data blocks are allocated. | |
613 | */ | |
614 | for (n = 1; n <= indirect_blks; n++) { | |
615 | /* | |
616 | * Get buffer_head for parent block, zero it out | |
617 | * and set the pointer to new one, then send | |
618 | * parent to disk. | |
619 | */ | |
620 | bh = sb_getblk(inode->i_sb, new_blocks[n-1]); | |
621 | branch[n].bh = bh; | |
622 | lock_buffer(bh); | |
623 | BUFFER_TRACE(bh, "call get_create_access"); | |
624 | err = ext3_journal_get_create_access(handle, bh); | |
625 | if (err) { | |
1da177e4 | 626 | unlock_buffer(bh); |
b47b2478 MC |
627 | brelse(bh); |
628 | goto failed; | |
629 | } | |
1da177e4 | 630 | |
b47b2478 MC |
631 | memset(bh->b_data, 0, blocksize); |
632 | branch[n].p = (__le32 *) bh->b_data + offsets[n]; | |
633 | branch[n].key = cpu_to_le32(new_blocks[n]); | |
634 | *branch[n].p = branch[n].key; | |
635 | if ( n == indirect_blks) { | |
636 | current_block = new_blocks[n]; | |
637 | /* | |
638 | * End of chain, update the last new metablock of | |
639 | * the chain to point to the new allocated | |
640 | * data blocks numbers | |
641 | */ | |
642 | for (i=1; i < num; i++) | |
643 | *(branch[n].p + i) = cpu_to_le32(++current_block); | |
1da177e4 | 644 | } |
b47b2478 MC |
645 | BUFFER_TRACE(bh, "marking uptodate"); |
646 | set_buffer_uptodate(bh); | |
647 | unlock_buffer(bh); | |
1da177e4 | 648 | |
b47b2478 MC |
649 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); |
650 | err = ext3_journal_dirty_metadata(handle, bh); | |
651 | if (err) | |
652 | goto failed; | |
653 | } | |
654 | *blks = num; | |
655 | return err; | |
656 | failed: | |
1da177e4 | 657 | /* Allocation failed, free what we already allocated */ |
b47b2478 | 658 | for (i = 1; i <= n ; i++) { |
1da177e4 LT |
659 | BUFFER_TRACE(branch[i].bh, "call journal_forget"); |
660 | ext3_journal_forget(handle, branch[i].bh); | |
661 | } | |
b47b2478 MC |
662 | for (i = 0; i <indirect_blks; i++) |
663 | ext3_free_blocks(handle, inode, new_blocks[i], 1); | |
664 | ||
665 | ext3_free_blocks(handle, inode, new_blocks[i], num); | |
666 | ||
1da177e4 LT |
667 | return err; |
668 | } | |
669 | ||
670 | /** | |
d6859bfc AM |
671 | * ext3_splice_branch - splice the allocated branch onto inode. |
672 | * @inode: owner | |
673 | * @block: (logical) number of block we are adding | |
674 | * @chain: chain of indirect blocks (with a missing link - see | |
675 | * ext3_alloc_branch) | |
676 | * @where: location of missing link | |
677 | * @num: number of indirect blocks we are adding | |
678 | * @blks: number of direct blocks we are adding | |
679 | * | |
680 | * This function fills the missing link and does all housekeeping needed in | |
681 | * inode (->i_blocks, etc.). In case of success we end up with the full | |
682 | * chain to new block and return 0. | |
1da177e4 | 683 | */ |
d6859bfc AM |
684 | static int ext3_splice_branch(handle_t *handle, struct inode *inode, |
685 | long block, Indirect *where, int num, int blks) | |
1da177e4 LT |
686 | { |
687 | int i; | |
688 | int err = 0; | |
d6859bfc | 689 | struct ext3_block_alloc_info *block_i; |
43d23f90 | 690 | ext3_fsblk_t current_block; |
d6859bfc AM |
691 | |
692 | block_i = EXT3_I(inode)->i_block_alloc_info; | |
1da177e4 LT |
693 | /* |
694 | * If we're splicing into a [td]indirect block (as opposed to the | |
695 | * inode) then we need to get write access to the [td]indirect block | |
696 | * before the splice. | |
697 | */ | |
698 | if (where->bh) { | |
699 | BUFFER_TRACE(where->bh, "get_write_access"); | |
700 | err = ext3_journal_get_write_access(handle, where->bh); | |
701 | if (err) | |
702 | goto err_out; | |
703 | } | |
1da177e4 LT |
704 | /* That's it */ |
705 | ||
706 | *where->p = where->key; | |
d6859bfc AM |
707 | |
708 | /* | |
709 | * Update the host buffer_head or inode to point to more just allocated | |
710 | * direct blocks blocks | |
711 | */ | |
b47b2478 | 712 | if (num == 0 && blks > 1) { |
5dea5176 | 713 | current_block = le32_to_cpu(where->key) + 1; |
b47b2478 MC |
714 | for (i = 1; i < blks; i++) |
715 | *(where->p + i ) = cpu_to_le32(current_block++); | |
716 | } | |
1da177e4 LT |
717 | |
718 | /* | |
719 | * update the most recently allocated logical & physical block | |
720 | * in i_block_alloc_info, to assist find the proper goal block for next | |
721 | * allocation | |
722 | */ | |
723 | if (block_i) { | |
b47b2478 | 724 | block_i->last_alloc_logical_block = block + blks - 1; |
d6859bfc | 725 | block_i->last_alloc_physical_block = |
5dea5176 | 726 | le32_to_cpu(where[num].key) + blks - 1; |
1da177e4 LT |
727 | } |
728 | ||
729 | /* We are done with atomic stuff, now do the rest of housekeeping */ | |
730 | ||
731 | inode->i_ctime = CURRENT_TIME_SEC; | |
732 | ext3_mark_inode_dirty(handle, inode); | |
733 | ||
734 | /* had we spliced it onto indirect block? */ | |
735 | if (where->bh) { | |
736 | /* | |
d6859bfc | 737 | * If we spliced it onto an indirect block, we haven't |
1da177e4 LT |
738 | * altered the inode. Note however that if it is being spliced |
739 | * onto an indirect block at the very end of the file (the | |
740 | * file is growing) then we *will* alter the inode to reflect | |
741 | * the new i_size. But that is not done here - it is done in | |
742 | * generic_commit_write->__mark_inode_dirty->ext3_dirty_inode. | |
743 | */ | |
744 | jbd_debug(5, "splicing indirect only\n"); | |
745 | BUFFER_TRACE(where->bh, "call ext3_journal_dirty_metadata"); | |
746 | err = ext3_journal_dirty_metadata(handle, where->bh); | |
ae6ddcc5 | 747 | if (err) |
1da177e4 LT |
748 | goto err_out; |
749 | } else { | |
750 | /* | |
751 | * OK, we spliced it into the inode itself on a direct block. | |
752 | * Inode was dirtied above. | |
753 | */ | |
754 | jbd_debug(5, "splicing direct\n"); | |
755 | } | |
756 | return err; | |
757 | ||
1da177e4 | 758 | err_out: |
b47b2478 | 759 | for (i = 1; i <= num; i++) { |
1da177e4 LT |
760 | BUFFER_TRACE(where[i].bh, "call journal_forget"); |
761 | ext3_journal_forget(handle, where[i].bh); | |
d6859bfc | 762 | ext3_free_blocks(handle,inode,le32_to_cpu(where[i-1].key),1); |
1da177e4 | 763 | } |
b47b2478 MC |
764 | ext3_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks); |
765 | ||
1da177e4 LT |
766 | return err; |
767 | } | |
768 | ||
769 | /* | |
770 | * Allocation strategy is simple: if we have to allocate something, we will | |
771 | * have to go the whole way to leaf. So let's do it before attaching anything | |
772 | * to tree, set linkage between the newborn blocks, write them if sync is | |
773 | * required, recheck the path, free and repeat if check fails, otherwise | |
774 | * set the last missing link (that will protect us from any truncate-generated | |
775 | * removals - all blocks on the path are immune now) and possibly force the | |
776 | * write on the parent block. | |
777 | * That has a nice additional property: no special recovery from the failed | |
778 | * allocations is needed - we simply release blocks and do not touch anything | |
779 | * reachable from inode. | |
780 | * | |
d6859bfc | 781 | * `handle' can be NULL if create == 0. |
1da177e4 LT |
782 | * |
783 | * The BKL may not be held on entry here. Be sure to take it early. | |
89747d36 MC |
784 | * return > 0, # of blocks mapped or allocated. |
785 | * return = 0, if plain lookup failed. | |
786 | * return < 0, error case. | |
1da177e4 | 787 | */ |
d6859bfc AM |
788 | int ext3_get_blocks_handle(handle_t *handle, struct inode *inode, |
789 | sector_t iblock, unsigned long maxblocks, | |
790 | struct buffer_head *bh_result, | |
89747d36 | 791 | int create, int extend_disksize) |
1da177e4 LT |
792 | { |
793 | int err = -EIO; | |
794 | int offsets[4]; | |
795 | Indirect chain[4]; | |
796 | Indirect *partial; | |
43d23f90 | 797 | ext3_fsblk_t goal; |
b47b2478 | 798 | int indirect_blks; |
89747d36 MC |
799 | int blocks_to_boundary = 0; |
800 | int depth; | |
1da177e4 | 801 | struct ext3_inode_info *ei = EXT3_I(inode); |
89747d36 | 802 | int count = 0; |
43d23f90 | 803 | ext3_fsblk_t first_block = 0; |
89747d36 | 804 | |
1da177e4 LT |
805 | |
806 | J_ASSERT(handle != NULL || create == 0); | |
d6859bfc | 807 | depth = ext3_block_to_path(inode,iblock,offsets,&blocks_to_boundary); |
1da177e4 LT |
808 | |
809 | if (depth == 0) | |
810 | goto out; | |
811 | ||
1da177e4 LT |
812 | partial = ext3_get_branch(inode, depth, offsets, chain, &err); |
813 | ||
814 | /* Simplest case - block found, no allocation needed */ | |
815 | if (!partial) { | |
5dea5176 | 816 | first_block = le32_to_cpu(chain[depth - 1].key); |
1da177e4 | 817 | clear_buffer_new(bh_result); |
89747d36 MC |
818 | count++; |
819 | /*map more blocks*/ | |
820 | while (count < maxblocks && count <= blocks_to_boundary) { | |
43d23f90 | 821 | ext3_fsblk_t blk; |
5dea5176 | 822 | |
89747d36 MC |
823 | if (!verify_chain(chain, partial)) { |
824 | /* | |
825 | * Indirect block might be removed by | |
826 | * truncate while we were reading it. | |
827 | * Handling of that case: forget what we've | |
828 | * got now. Flag the err as EAGAIN, so it | |
829 | * will reread. | |
830 | */ | |
831 | err = -EAGAIN; | |
832 | count = 0; | |
833 | break; | |
834 | } | |
5dea5176 MC |
835 | blk = le32_to_cpu(*(chain[depth-1].p + count)); |
836 | ||
837 | if (blk == first_block + count) | |
89747d36 MC |
838 | count++; |
839 | else | |
840 | break; | |
841 | } | |
842 | if (err != -EAGAIN) | |
843 | goto got_it; | |
1da177e4 LT |
844 | } |
845 | ||
846 | /* Next simple case - plain lookup or failed read of indirect block */ | |
fe55c452 MC |
847 | if (!create || err == -EIO) |
848 | goto cleanup; | |
849 | ||
97461518 | 850 | mutex_lock(&ei->truncate_mutex); |
fe55c452 MC |
851 | |
852 | /* | |
853 | * If the indirect block is missing while we are reading | |
854 | * the chain(ext3_get_branch() returns -EAGAIN err), or | |
855 | * if the chain has been changed after we grab the semaphore, | |
856 | * (either because another process truncated this branch, or | |
857 | * another get_block allocated this branch) re-grab the chain to see if | |
858 | * the request block has been allocated or not. | |
859 | * | |
860 | * Since we already block the truncate/other get_block | |
861 | * at this point, we will have the current copy of the chain when we | |
862 | * splice the branch into the tree. | |
863 | */ | |
864 | if (err == -EAGAIN || !verify_chain(chain, partial)) { | |
1da177e4 | 865 | while (partial > chain) { |
1da177e4 LT |
866 | brelse(partial->bh); |
867 | partial--; | |
868 | } | |
fe55c452 MC |
869 | partial = ext3_get_branch(inode, depth, offsets, chain, &err); |
870 | if (!partial) { | |
89747d36 | 871 | count++; |
97461518 | 872 | mutex_unlock(&ei->truncate_mutex); |
fe55c452 MC |
873 | if (err) |
874 | goto cleanup; | |
875 | clear_buffer_new(bh_result); | |
876 | goto got_it; | |
877 | } | |
1da177e4 LT |
878 | } |
879 | ||
880 | /* | |
fe55c452 MC |
881 | * Okay, we need to do block allocation. Lazily initialize the block |
882 | * allocation info here if necessary | |
883 | */ | |
884 | if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info)) | |
1da177e4 | 885 | ext3_init_block_alloc_info(inode); |
1da177e4 | 886 | |
fe55c452 | 887 | goal = ext3_find_goal(inode, iblock, chain, partial); |
1da177e4 | 888 | |
b47b2478 MC |
889 | /* the number of blocks need to allocate for [d,t]indirect blocks */ |
890 | indirect_blks = (chain + depth) - partial - 1; | |
1da177e4 | 891 | |
b47b2478 MC |
892 | /* |
893 | * Next look up the indirect map to count the totoal number of | |
894 | * direct blocks to allocate for this branch. | |
895 | */ | |
896 | count = ext3_blks_to_allocate(partial, indirect_blks, | |
897 | maxblocks, blocks_to_boundary); | |
1da177e4 LT |
898 | /* |
899 | * Block out ext3_truncate while we alter the tree | |
900 | */ | |
b47b2478 | 901 | err = ext3_alloc_branch(handle, inode, indirect_blks, &count, goal, |
fe55c452 | 902 | offsets + (partial - chain), partial); |
1da177e4 | 903 | |
fe55c452 MC |
904 | /* |
905 | * The ext3_splice_branch call will free and forget any buffers | |
1da177e4 LT |
906 | * on the new chain if there is a failure, but that risks using |
907 | * up transaction credits, especially for bitmaps where the | |
908 | * credits cannot be returned. Can we handle this somehow? We | |
fe55c452 MC |
909 | * may need to return -EAGAIN upwards in the worst case. --sct |
910 | */ | |
1da177e4 | 911 | if (!err) |
b47b2478 MC |
912 | err = ext3_splice_branch(handle, inode, iblock, |
913 | partial, indirect_blks, count); | |
fe55c452 | 914 | /* |
97461518 | 915 | * i_disksize growing is protected by truncate_mutex. Don't forget to |
fe55c452 MC |
916 | * protect it if you're about to implement concurrent |
917 | * ext3_get_block() -bzzz | |
918 | */ | |
1da177e4 LT |
919 | if (!err && extend_disksize && inode->i_size > ei->i_disksize) |
920 | ei->i_disksize = inode->i_size; | |
97461518 | 921 | mutex_unlock(&ei->truncate_mutex); |
1da177e4 LT |
922 | if (err) |
923 | goto cleanup; | |
924 | ||
925 | set_buffer_new(bh_result); | |
fe55c452 MC |
926 | got_it: |
927 | map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); | |
20acaa18 | 928 | if (count > blocks_to_boundary) |
fe55c452 | 929 | set_buffer_boundary(bh_result); |
89747d36 | 930 | err = count; |
fe55c452 MC |
931 | /* Clean up and exit */ |
932 | partial = chain + depth - 1; /* the whole chain */ | |
933 | cleanup: | |
1da177e4 | 934 | while (partial > chain) { |
fe55c452 | 935 | BUFFER_TRACE(partial->bh, "call brelse"); |
1da177e4 LT |
936 | brelse(partial->bh); |
937 | partial--; | |
938 | } | |
fe55c452 MC |
939 | BUFFER_TRACE(bh_result, "returned"); |
940 | out: | |
941 | return err; | |
1da177e4 LT |
942 | } |
943 | ||
1da177e4 LT |
944 | #define DIO_CREDITS (EXT3_RESERVE_TRANS_BLOCKS + 32) |
945 | ||
f91a2ad2 BP |
946 | static int ext3_get_block(struct inode *inode, sector_t iblock, |
947 | struct buffer_head *bh_result, int create) | |
1da177e4 | 948 | { |
3e4fdaf8 | 949 | handle_t *handle = ext3_journal_current_handle(); |
1da177e4 | 950 | int ret = 0; |
1d8fa7a2 | 951 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; |
1da177e4 | 952 | |
89747d36 | 953 | if (!create) |
1da177e4 LT |
954 | goto get_block; /* A read */ |
955 | ||
89747d36 MC |
956 | if (max_blocks == 1) |
957 | goto get_block; /* A single block get */ | |
958 | ||
1da177e4 LT |
959 | if (handle->h_transaction->t_state == T_LOCKED) { |
960 | /* | |
961 | * Huge direct-io writes can hold off commits for long | |
962 | * periods of time. Let this commit run. | |
963 | */ | |
964 | ext3_journal_stop(handle); | |
965 | handle = ext3_journal_start(inode, DIO_CREDITS); | |
966 | if (IS_ERR(handle)) | |
967 | ret = PTR_ERR(handle); | |
968 | goto get_block; | |
969 | } | |
970 | ||
971 | if (handle->h_buffer_credits <= EXT3_RESERVE_TRANS_BLOCKS) { | |
972 | /* | |
973 | * Getting low on buffer credits... | |
974 | */ | |
975 | ret = ext3_journal_extend(handle, DIO_CREDITS); | |
976 | if (ret > 0) { | |
977 | /* | |
978 | * Couldn't extend the transaction. Start a new one. | |
979 | */ | |
980 | ret = ext3_journal_restart(handle, DIO_CREDITS); | |
981 | } | |
982 | } | |
983 | ||
984 | get_block: | |
89747d36 MC |
985 | if (ret == 0) { |
986 | ret = ext3_get_blocks_handle(handle, inode, iblock, | |
987 | max_blocks, bh_result, create, 0); | |
988 | if (ret > 0) { | |
989 | bh_result->b_size = (ret << inode->i_blkbits); | |
990 | ret = 0; | |
991 | } | |
992 | } | |
1da177e4 LT |
993 | return ret; |
994 | } | |
995 | ||
1da177e4 LT |
996 | /* |
997 | * `handle' can be NULL if create is zero | |
998 | */ | |
d6859bfc AM |
999 | struct buffer_head *ext3_getblk(handle_t *handle, struct inode *inode, |
1000 | long block, int create, int *errp) | |
1da177e4 LT |
1001 | { |
1002 | struct buffer_head dummy; | |
1003 | int fatal = 0, err; | |
1004 | ||
1005 | J_ASSERT(handle != NULL || create == 0); | |
1006 | ||
1007 | dummy.b_state = 0; | |
1008 | dummy.b_blocknr = -1000; | |
1009 | buffer_trace_init(&dummy.b_history); | |
89747d36 MC |
1010 | err = ext3_get_blocks_handle(handle, inode, block, 1, |
1011 | &dummy, create, 1); | |
3665d0e5 BP |
1012 | /* |
1013 | * ext3_get_blocks_handle() returns number of blocks | |
1014 | * mapped. 0 in case of a HOLE. | |
1015 | */ | |
1016 | if (err > 0) { | |
1017 | if (err > 1) | |
1018 | WARN_ON(1); | |
89747d36 | 1019 | err = 0; |
89747d36 MC |
1020 | } |
1021 | *errp = err; | |
1022 | if (!err && buffer_mapped(&dummy)) { | |
1da177e4 LT |
1023 | struct buffer_head *bh; |
1024 | bh = sb_getblk(inode->i_sb, dummy.b_blocknr); | |
2973dfdb GOC |
1025 | if (!bh) { |
1026 | *errp = -EIO; | |
1027 | goto err; | |
1028 | } | |
1da177e4 LT |
1029 | if (buffer_new(&dummy)) { |
1030 | J_ASSERT(create != 0); | |
1031 | J_ASSERT(handle != 0); | |
1032 | ||
d6859bfc AM |
1033 | /* |
1034 | * Now that we do not always journal data, we should | |
1035 | * keep in mind whether this should always journal the | |
1036 | * new buffer as metadata. For now, regular file | |
1037 | * writes use ext3_get_block instead, so it's not a | |
1038 | * problem. | |
1039 | */ | |
1da177e4 LT |
1040 | lock_buffer(bh); |
1041 | BUFFER_TRACE(bh, "call get_create_access"); | |
1042 | fatal = ext3_journal_get_create_access(handle, bh); | |
1043 | if (!fatal && !buffer_uptodate(bh)) { | |
d6859bfc | 1044 | memset(bh->b_data,0,inode->i_sb->s_blocksize); |
1da177e4 LT |
1045 | set_buffer_uptodate(bh); |
1046 | } | |
1047 | unlock_buffer(bh); | |
1048 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
1049 | err = ext3_journal_dirty_metadata(handle, bh); | |
1050 | if (!fatal) | |
1051 | fatal = err; | |
1052 | } else { | |
1053 | BUFFER_TRACE(bh, "not a new buffer"); | |
1054 | } | |
1055 | if (fatal) { | |
1056 | *errp = fatal; | |
1057 | brelse(bh); | |
1058 | bh = NULL; | |
1059 | } | |
1060 | return bh; | |
1061 | } | |
2973dfdb | 1062 | err: |
1da177e4 LT |
1063 | return NULL; |
1064 | } | |
1065 | ||
d6859bfc | 1066 | struct buffer_head *ext3_bread(handle_t *handle, struct inode *inode, |
1da177e4 LT |
1067 | int block, int create, int *err) |
1068 | { | |
1069 | struct buffer_head * bh; | |
1070 | ||
1071 | bh = ext3_getblk(handle, inode, block, create, err); | |
1072 | if (!bh) | |
1073 | return bh; | |
1074 | if (buffer_uptodate(bh)) | |
1075 | return bh; | |
caa38fb0 | 1076 | ll_rw_block(READ_META, 1, &bh); |
1da177e4 LT |
1077 | wait_on_buffer(bh); |
1078 | if (buffer_uptodate(bh)) | |
1079 | return bh; | |
1080 | put_bh(bh); | |
1081 | *err = -EIO; | |
1082 | return NULL; | |
1083 | } | |
1084 | ||
1085 | static int walk_page_buffers( handle_t *handle, | |
1086 | struct buffer_head *head, | |
1087 | unsigned from, | |
1088 | unsigned to, | |
1089 | int *partial, | |
1090 | int (*fn)( handle_t *handle, | |
1091 | struct buffer_head *bh)) | |
1092 | { | |
1093 | struct buffer_head *bh; | |
1094 | unsigned block_start, block_end; | |
1095 | unsigned blocksize = head->b_size; | |
1096 | int err, ret = 0; | |
1097 | struct buffer_head *next; | |
1098 | ||
1099 | for ( bh = head, block_start = 0; | |
1100 | ret == 0 && (bh != head || !block_start); | |
e9ad5620 | 1101 | block_start = block_end, bh = next) |
1da177e4 LT |
1102 | { |
1103 | next = bh->b_this_page; | |
1104 | block_end = block_start + blocksize; | |
1105 | if (block_end <= from || block_start >= to) { | |
1106 | if (partial && !buffer_uptodate(bh)) | |
1107 | *partial = 1; | |
1108 | continue; | |
1109 | } | |
1110 | err = (*fn)(handle, bh); | |
1111 | if (!ret) | |
1112 | ret = err; | |
1113 | } | |
1114 | return ret; | |
1115 | } | |
1116 | ||
1117 | /* | |
1118 | * To preserve ordering, it is essential that the hole instantiation and | |
1119 | * the data write be encapsulated in a single transaction. We cannot | |
1120 | * close off a transaction and start a new one between the ext3_get_block() | |
1121 | * and the commit_write(). So doing the journal_start at the start of | |
1122 | * prepare_write() is the right place. | |
1123 | * | |
1124 | * Also, this function can nest inside ext3_writepage() -> | |
1125 | * block_write_full_page(). In that case, we *know* that ext3_writepage() | |
1126 | * has generated enough buffer credits to do the whole page. So we won't | |
1127 | * block on the journal in that case, which is good, because the caller may | |
1128 | * be PF_MEMALLOC. | |
1129 | * | |
1130 | * By accident, ext3 can be reentered when a transaction is open via | |
1131 | * quota file writes. If we were to commit the transaction while thus | |
1132 | * reentered, there can be a deadlock - we would be holding a quota | |
1133 | * lock, and the commit would never complete if another thread had a | |
1134 | * transaction open and was blocking on the quota lock - a ranking | |
1135 | * violation. | |
1136 | * | |
1137 | * So what we do is to rely on the fact that journal_stop/journal_start | |
1138 | * will _not_ run commit under these circumstances because handle->h_ref | |
1139 | * is elevated. We'll still have enough credits for the tiny quotafile | |
ae6ddcc5 | 1140 | * write. |
1da177e4 | 1141 | */ |
d6859bfc AM |
1142 | static int do_journal_get_write_access(handle_t *handle, |
1143 | struct buffer_head *bh) | |
1da177e4 LT |
1144 | { |
1145 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1146 | return 0; | |
1147 | return ext3_journal_get_write_access(handle, bh); | |
1148 | } | |
1149 | ||
1150 | static int ext3_prepare_write(struct file *file, struct page *page, | |
1151 | unsigned from, unsigned to) | |
1152 | { | |
1153 | struct inode *inode = page->mapping->host; | |
1aa9b4b9 | 1154 | int ret, needed_blocks = ext3_writepage_trans_blocks(inode); |
1da177e4 LT |
1155 | handle_t *handle; |
1156 | int retries = 0; | |
1157 | ||
1158 | retry: | |
1159 | handle = ext3_journal_start(inode, needed_blocks); | |
1aa9b4b9 AM |
1160 | if (IS_ERR(handle)) { |
1161 | ret = PTR_ERR(handle); | |
1162 | goto out; | |
1163 | } | |
0e31f51d | 1164 | if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode)) |
1da177e4 LT |
1165 | ret = nobh_prepare_write(page, from, to, ext3_get_block); |
1166 | else | |
1167 | ret = block_prepare_write(page, from, to, ext3_get_block); | |
1168 | if (ret) | |
1aa9b4b9 | 1169 | goto prepare_write_failed; |
1da177e4 LT |
1170 | |
1171 | if (ext3_should_journal_data(inode)) { | |
1172 | ret = walk_page_buffers(handle, page_buffers(page), | |
1173 | from, to, NULL, do_journal_get_write_access); | |
1174 | } | |
1aa9b4b9 AM |
1175 | prepare_write_failed: |
1176 | if (ret) | |
1177 | ext3_journal_stop(handle); | |
1da177e4 LT |
1178 | if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries)) |
1179 | goto retry; | |
1aa9b4b9 | 1180 | out: |
1da177e4 LT |
1181 | return ret; |
1182 | } | |
1183 | ||
d6859bfc | 1184 | int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh) |
1da177e4 LT |
1185 | { |
1186 | int err = journal_dirty_data(handle, bh); | |
1187 | if (err) | |
1188 | ext3_journal_abort_handle(__FUNCTION__, __FUNCTION__, | |
1189 | bh, handle,err); | |
1190 | return err; | |
1191 | } | |
1192 | ||
1193 | /* For commit_write() in data=journal mode */ | |
1194 | static int commit_write_fn(handle_t *handle, struct buffer_head *bh) | |
1195 | { | |
1196 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1197 | return 0; | |
1198 | set_buffer_uptodate(bh); | |
1199 | return ext3_journal_dirty_metadata(handle, bh); | |
1200 | } | |
1201 | ||
1202 | /* | |
1203 | * We need to pick up the new inode size which generic_commit_write gave us | |
1204 | * `file' can be NULL - eg, when called from page_symlink(). | |
1205 | * | |
1206 | * ext3 never places buffers on inode->i_mapping->private_list. metadata | |
1207 | * buffers are managed internally. | |
1208 | */ | |
1da177e4 LT |
1209 | static int ext3_ordered_commit_write(struct file *file, struct page *page, |
1210 | unsigned from, unsigned to) | |
1211 | { | |
1212 | handle_t *handle = ext3_journal_current_handle(); | |
1213 | struct inode *inode = page->mapping->host; | |
1214 | int ret = 0, ret2; | |
1215 | ||
1216 | ret = walk_page_buffers(handle, page_buffers(page), | |
1217 | from, to, NULL, ext3_journal_dirty_data); | |
1218 | ||
1219 | if (ret == 0) { | |
1220 | /* | |
1221 | * generic_commit_write() will run mark_inode_dirty() if i_size | |
1222 | * changes. So let's piggyback the i_disksize mark_inode_dirty | |
1223 | * into that. | |
1224 | */ | |
1225 | loff_t new_i_size; | |
1226 | ||
1227 | new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
1228 | if (new_i_size > EXT3_I(inode)->i_disksize) | |
1229 | EXT3_I(inode)->i_disksize = new_i_size; | |
1230 | ret = generic_commit_write(file, page, from, to); | |
1231 | } | |
1232 | ret2 = ext3_journal_stop(handle); | |
1233 | if (!ret) | |
1234 | ret = ret2; | |
1235 | return ret; | |
1236 | } | |
1237 | ||
1238 | static int ext3_writeback_commit_write(struct file *file, struct page *page, | |
1239 | unsigned from, unsigned to) | |
1240 | { | |
1241 | handle_t *handle = ext3_journal_current_handle(); | |
1242 | struct inode *inode = page->mapping->host; | |
1243 | int ret = 0, ret2; | |
1244 | loff_t new_i_size; | |
1245 | ||
1246 | new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
1247 | if (new_i_size > EXT3_I(inode)->i_disksize) | |
1248 | EXT3_I(inode)->i_disksize = new_i_size; | |
1249 | ||
0e31f51d | 1250 | if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode)) |
1da177e4 LT |
1251 | ret = nobh_commit_write(file, page, from, to); |
1252 | else | |
1253 | ret = generic_commit_write(file, page, from, to); | |
1254 | ||
1255 | ret2 = ext3_journal_stop(handle); | |
1256 | if (!ret) | |
1257 | ret = ret2; | |
1258 | return ret; | |
1259 | } | |
1260 | ||
1261 | static int ext3_journalled_commit_write(struct file *file, | |
1262 | struct page *page, unsigned from, unsigned to) | |
1263 | { | |
1264 | handle_t *handle = ext3_journal_current_handle(); | |
1265 | struct inode *inode = page->mapping->host; | |
1266 | int ret = 0, ret2; | |
1267 | int partial = 0; | |
1268 | loff_t pos; | |
1269 | ||
1270 | /* | |
1271 | * Here we duplicate the generic_commit_write() functionality | |
1272 | */ | |
1273 | pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
1274 | ||
1275 | ret = walk_page_buffers(handle, page_buffers(page), from, | |
1276 | to, &partial, commit_write_fn); | |
1277 | if (!partial) | |
1278 | SetPageUptodate(page); | |
1279 | if (pos > inode->i_size) | |
1280 | i_size_write(inode, pos); | |
1281 | EXT3_I(inode)->i_state |= EXT3_STATE_JDATA; | |
1282 | if (inode->i_size > EXT3_I(inode)->i_disksize) { | |
1283 | EXT3_I(inode)->i_disksize = inode->i_size; | |
1284 | ret2 = ext3_mark_inode_dirty(handle, inode); | |
ae6ddcc5 | 1285 | if (!ret) |
1da177e4 LT |
1286 | ret = ret2; |
1287 | } | |
1288 | ret2 = ext3_journal_stop(handle); | |
1289 | if (!ret) | |
1290 | ret = ret2; | |
1291 | return ret; | |
1292 | } | |
1293 | ||
ae6ddcc5 | 1294 | /* |
1da177e4 LT |
1295 | * bmap() is special. It gets used by applications such as lilo and by |
1296 | * the swapper to find the on-disk block of a specific piece of data. | |
1297 | * | |
1298 | * Naturally, this is dangerous if the block concerned is still in the | |
1299 | * journal. If somebody makes a swapfile on an ext3 data-journaling | |
1300 | * filesystem and enables swap, then they may get a nasty shock when the | |
1301 | * data getting swapped to that swapfile suddenly gets overwritten by | |
1302 | * the original zero's written out previously to the journal and | |
ae6ddcc5 | 1303 | * awaiting writeback in the kernel's buffer cache. |
1da177e4 LT |
1304 | * |
1305 | * So, if we see any bmap calls here on a modified, data-journaled file, | |
ae6ddcc5 | 1306 | * take extra steps to flush any blocks which might be in the cache. |
1da177e4 LT |
1307 | */ |
1308 | static sector_t ext3_bmap(struct address_space *mapping, sector_t block) | |
1309 | { | |
1310 | struct inode *inode = mapping->host; | |
1311 | journal_t *journal; | |
1312 | int err; | |
1313 | ||
1314 | if (EXT3_I(inode)->i_state & EXT3_STATE_JDATA) { | |
ae6ddcc5 | 1315 | /* |
1da177e4 LT |
1316 | * This is a REALLY heavyweight approach, but the use of |
1317 | * bmap on dirty files is expected to be extremely rare: | |
1318 | * only if we run lilo or swapon on a freshly made file | |
ae6ddcc5 | 1319 | * do we expect this to happen. |
1da177e4 LT |
1320 | * |
1321 | * (bmap requires CAP_SYS_RAWIO so this does not | |
1322 | * represent an unprivileged user DOS attack --- we'd be | |
1323 | * in trouble if mortal users could trigger this path at | |
ae6ddcc5 | 1324 | * will.) |
1da177e4 LT |
1325 | * |
1326 | * NB. EXT3_STATE_JDATA is not set on files other than | |
1327 | * regular files. If somebody wants to bmap a directory | |
1328 | * or symlink and gets confused because the buffer | |
1329 | * hasn't yet been flushed to disk, they deserve | |
1330 | * everything they get. | |
1331 | */ | |
1332 | ||
1333 | EXT3_I(inode)->i_state &= ~EXT3_STATE_JDATA; | |
1334 | journal = EXT3_JOURNAL(inode); | |
1335 | journal_lock_updates(journal); | |
1336 | err = journal_flush(journal); | |
1337 | journal_unlock_updates(journal); | |
1338 | ||
1339 | if (err) | |
1340 | return 0; | |
1341 | } | |
1342 | ||
1343 | return generic_block_bmap(mapping,block,ext3_get_block); | |
1344 | } | |
1345 | ||
1346 | static int bget_one(handle_t *handle, struct buffer_head *bh) | |
1347 | { | |
1348 | get_bh(bh); | |
1349 | return 0; | |
1350 | } | |
1351 | ||
1352 | static int bput_one(handle_t *handle, struct buffer_head *bh) | |
1353 | { | |
1354 | put_bh(bh); | |
1355 | return 0; | |
1356 | } | |
1357 | ||
1358 | static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh) | |
1359 | { | |
1360 | if (buffer_mapped(bh)) | |
1361 | return ext3_journal_dirty_data(handle, bh); | |
1362 | return 0; | |
1363 | } | |
1364 | ||
1365 | /* | |
1366 | * Note that we always start a transaction even if we're not journalling | |
1367 | * data. This is to preserve ordering: any hole instantiation within | |
1368 | * __block_write_full_page -> ext3_get_block() should be journalled | |
1369 | * along with the data so we don't crash and then get metadata which | |
1370 | * refers to old data. | |
1371 | * | |
1372 | * In all journalling modes block_write_full_page() will start the I/O. | |
1373 | * | |
1374 | * Problem: | |
1375 | * | |
1376 | * ext3_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() -> | |
1377 | * ext3_writepage() | |
1378 | * | |
1379 | * Similar for: | |
1380 | * | |
1381 | * ext3_file_write() -> generic_file_write() -> __alloc_pages() -> ... | |
1382 | * | |
1383 | * Same applies to ext3_get_block(). We will deadlock on various things like | |
97461518 | 1384 | * lock_journal and i_truncate_mutex. |
1da177e4 LT |
1385 | * |
1386 | * Setting PF_MEMALLOC here doesn't work - too many internal memory | |
1387 | * allocations fail. | |
1388 | * | |
1389 | * 16May01: If we're reentered then journal_current_handle() will be | |
1390 | * non-zero. We simply *return*. | |
1391 | * | |
1392 | * 1 July 2001: @@@ FIXME: | |
1393 | * In journalled data mode, a data buffer may be metadata against the | |
1394 | * current transaction. But the same file is part of a shared mapping | |
1395 | * and someone does a writepage() on it. | |
1396 | * | |
1397 | * We will move the buffer onto the async_data list, but *after* it has | |
1398 | * been dirtied. So there's a small window where we have dirty data on | |
1399 | * BJ_Metadata. | |
1400 | * | |
1401 | * Note that this only applies to the last partial page in the file. The | |
1402 | * bit which block_write_full_page() uses prepare/commit for. (That's | |
1403 | * broken code anyway: it's wrong for msync()). | |
1404 | * | |
1405 | * It's a rare case: affects the final partial page, for journalled data | |
1406 | * where the file is subject to bith write() and writepage() in the same | |
1407 | * transction. To fix it we'll need a custom block_write_full_page(). | |
1408 | * We'll probably need that anyway for journalling writepage() output. | |
1409 | * | |
1410 | * We don't honour synchronous mounts for writepage(). That would be | |
1411 | * disastrous. Any write() or metadata operation will sync the fs for | |
1412 | * us. | |
1413 | * | |
1414 | * AKPM2: if all the page's buffers are mapped to disk and !data=journal, | |
1415 | * we don't need to open a transaction here. | |
1416 | */ | |
1417 | static int ext3_ordered_writepage(struct page *page, | |
d6859bfc | 1418 | struct writeback_control *wbc) |
1da177e4 LT |
1419 | { |
1420 | struct inode *inode = page->mapping->host; | |
1421 | struct buffer_head *page_bufs; | |
1422 | handle_t *handle = NULL; | |
1423 | int ret = 0; | |
1424 | int err; | |
1425 | ||
1426 | J_ASSERT(PageLocked(page)); | |
1427 | ||
1428 | /* | |
1429 | * We give up here if we're reentered, because it might be for a | |
1430 | * different filesystem. | |
1431 | */ | |
1432 | if (ext3_journal_current_handle()) | |
1433 | goto out_fail; | |
1434 | ||
1435 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); | |
1436 | ||
1437 | if (IS_ERR(handle)) { | |
1438 | ret = PTR_ERR(handle); | |
1439 | goto out_fail; | |
1440 | } | |
1441 | ||
1442 | if (!page_has_buffers(page)) { | |
1443 | create_empty_buffers(page, inode->i_sb->s_blocksize, | |
1444 | (1 << BH_Dirty)|(1 << BH_Uptodate)); | |
1445 | } | |
1446 | page_bufs = page_buffers(page); | |
1447 | walk_page_buffers(handle, page_bufs, 0, | |
1448 | PAGE_CACHE_SIZE, NULL, bget_one); | |
1449 | ||
1450 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1451 | ||
1452 | /* | |
1453 | * The page can become unlocked at any point now, and | |
1454 | * truncate can then come in and change things. So we | |
1455 | * can't touch *page from now on. But *page_bufs is | |
1456 | * safe due to elevated refcount. | |
1457 | */ | |
1458 | ||
1459 | /* | |
ae6ddcc5 | 1460 | * And attach them to the current transaction. But only if |
1da177e4 LT |
1461 | * block_write_full_page() succeeded. Otherwise they are unmapped, |
1462 | * and generally junk. | |
1463 | */ | |
1464 | if (ret == 0) { | |
1465 | err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE, | |
1466 | NULL, journal_dirty_data_fn); | |
1467 | if (!ret) | |
1468 | ret = err; | |
1469 | } | |
1470 | walk_page_buffers(handle, page_bufs, 0, | |
1471 | PAGE_CACHE_SIZE, NULL, bput_one); | |
1472 | err = ext3_journal_stop(handle); | |
1473 | if (!ret) | |
1474 | ret = err; | |
1475 | return ret; | |
1476 | ||
1477 | out_fail: | |
1478 | redirty_page_for_writepage(wbc, page); | |
1479 | unlock_page(page); | |
1480 | return ret; | |
1481 | } | |
1482 | ||
1da177e4 LT |
1483 | static int ext3_writeback_writepage(struct page *page, |
1484 | struct writeback_control *wbc) | |
1485 | { | |
1486 | struct inode *inode = page->mapping->host; | |
1487 | handle_t *handle = NULL; | |
1488 | int ret = 0; | |
1489 | int err; | |
1490 | ||
1491 | if (ext3_journal_current_handle()) | |
1492 | goto out_fail; | |
1493 | ||
1494 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); | |
1495 | if (IS_ERR(handle)) { | |
1496 | ret = PTR_ERR(handle); | |
1497 | goto out_fail; | |
1498 | } | |
1499 | ||
0e31f51d | 1500 | if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode)) |
1da177e4 LT |
1501 | ret = nobh_writepage(page, ext3_get_block, wbc); |
1502 | else | |
1503 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1504 | ||
1505 | err = ext3_journal_stop(handle); | |
1506 | if (!ret) | |
1507 | ret = err; | |
1508 | return ret; | |
1509 | ||
1510 | out_fail: | |
1511 | redirty_page_for_writepage(wbc, page); | |
1512 | unlock_page(page); | |
1513 | return ret; | |
1514 | } | |
1515 | ||
1516 | static int ext3_journalled_writepage(struct page *page, | |
1517 | struct writeback_control *wbc) | |
1518 | { | |
1519 | struct inode *inode = page->mapping->host; | |
1520 | handle_t *handle = NULL; | |
1521 | int ret = 0; | |
1522 | int err; | |
1523 | ||
1524 | if (ext3_journal_current_handle()) | |
1525 | goto no_write; | |
1526 | ||
1527 | handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); | |
1528 | if (IS_ERR(handle)) { | |
1529 | ret = PTR_ERR(handle); | |
1530 | goto no_write; | |
1531 | } | |
1532 | ||
1533 | if (!page_has_buffers(page) || PageChecked(page)) { | |
1534 | /* | |
1535 | * It's mmapped pagecache. Add buffers and journal it. There | |
1536 | * doesn't seem much point in redirtying the page here. | |
1537 | */ | |
1538 | ClearPageChecked(page); | |
1539 | ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, | |
1540 | ext3_get_block); | |
ab4eb43c DL |
1541 | if (ret != 0) { |
1542 | ext3_journal_stop(handle); | |
1da177e4 | 1543 | goto out_unlock; |
ab4eb43c | 1544 | } |
1da177e4 LT |
1545 | ret = walk_page_buffers(handle, page_buffers(page), 0, |
1546 | PAGE_CACHE_SIZE, NULL, do_journal_get_write_access); | |
1547 | ||
1548 | err = walk_page_buffers(handle, page_buffers(page), 0, | |
1549 | PAGE_CACHE_SIZE, NULL, commit_write_fn); | |
1550 | if (ret == 0) | |
1551 | ret = err; | |
1552 | EXT3_I(inode)->i_state |= EXT3_STATE_JDATA; | |
1553 | unlock_page(page); | |
1554 | } else { | |
1555 | /* | |
1556 | * It may be a page full of checkpoint-mode buffers. We don't | |
1557 | * really know unless we go poke around in the buffer_heads. | |
1558 | * But block_write_full_page will do the right thing. | |
1559 | */ | |
1560 | ret = block_write_full_page(page, ext3_get_block, wbc); | |
1561 | } | |
1562 | err = ext3_journal_stop(handle); | |
1563 | if (!ret) | |
1564 | ret = err; | |
1565 | out: | |
1566 | return ret; | |
1567 | ||
1568 | no_write: | |
1569 | redirty_page_for_writepage(wbc, page); | |
1570 | out_unlock: | |
1571 | unlock_page(page); | |
1572 | goto out; | |
1573 | } | |
1574 | ||
1575 | static int ext3_readpage(struct file *file, struct page *page) | |
1576 | { | |
1577 | return mpage_readpage(page, ext3_get_block); | |
1578 | } | |
1579 | ||
1580 | static int | |
1581 | ext3_readpages(struct file *file, struct address_space *mapping, | |
1582 | struct list_head *pages, unsigned nr_pages) | |
1583 | { | |
1584 | return mpage_readpages(mapping, pages, nr_pages, ext3_get_block); | |
1585 | } | |
1586 | ||
2ff28e22 | 1587 | static void ext3_invalidatepage(struct page *page, unsigned long offset) |
1da177e4 LT |
1588 | { |
1589 | journal_t *journal = EXT3_JOURNAL(page->mapping->host); | |
1590 | ||
1591 | /* | |
1592 | * If it's a full truncate we just forget about the pending dirtying | |
1593 | */ | |
1594 | if (offset == 0) | |
1595 | ClearPageChecked(page); | |
1596 | ||
2ff28e22 | 1597 | journal_invalidatepage(journal, page, offset); |
1da177e4 LT |
1598 | } |
1599 | ||
27496a8c | 1600 | static int ext3_releasepage(struct page *page, gfp_t wait) |
1da177e4 LT |
1601 | { |
1602 | journal_t *journal = EXT3_JOURNAL(page->mapping->host); | |
1603 | ||
1604 | WARN_ON(PageChecked(page)); | |
1605 | if (!page_has_buffers(page)) | |
1606 | return 0; | |
1607 | return journal_try_to_free_buffers(journal, page, wait); | |
1608 | } | |
1609 | ||
1610 | /* | |
1611 | * If the O_DIRECT write will extend the file then add this inode to the | |
1612 | * orphan list. So recovery will truncate it back to the original size | |
1613 | * if the machine crashes during the write. | |
1614 | * | |
1615 | * If the O_DIRECT write is intantiating holes inside i_size and the machine | |
1616 | * crashes then stale disk data _may_ be exposed inside the file. | |
1617 | */ | |
1618 | static ssize_t ext3_direct_IO(int rw, struct kiocb *iocb, | |
1619 | const struct iovec *iov, loff_t offset, | |
1620 | unsigned long nr_segs) | |
1621 | { | |
1622 | struct file *file = iocb->ki_filp; | |
1623 | struct inode *inode = file->f_mapping->host; | |
1624 | struct ext3_inode_info *ei = EXT3_I(inode); | |
1625 | handle_t *handle = NULL; | |
1626 | ssize_t ret; | |
1627 | int orphan = 0; | |
1628 | size_t count = iov_length(iov, nr_segs); | |
1629 | ||
1630 | if (rw == WRITE) { | |
1631 | loff_t final_size = offset + count; | |
1632 | ||
1633 | handle = ext3_journal_start(inode, DIO_CREDITS); | |
1634 | if (IS_ERR(handle)) { | |
1635 | ret = PTR_ERR(handle); | |
1636 | goto out; | |
1637 | } | |
1638 | if (final_size > inode->i_size) { | |
1639 | ret = ext3_orphan_add(handle, inode); | |
1640 | if (ret) | |
1641 | goto out_stop; | |
1642 | orphan = 1; | |
1643 | ei->i_disksize = inode->i_size; | |
1644 | } | |
1645 | } | |
1646 | ||
ae6ddcc5 | 1647 | ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, |
1da177e4 | 1648 | offset, nr_segs, |
f91a2ad2 | 1649 | ext3_get_block, NULL); |
1da177e4 LT |
1650 | |
1651 | /* | |
f91a2ad2 | 1652 | * Reacquire the handle: ext3_get_block() can restart the transaction |
1da177e4 | 1653 | */ |
3e4fdaf8 | 1654 | handle = ext3_journal_current_handle(); |
1da177e4 LT |
1655 | |
1656 | out_stop: | |
1657 | if (handle) { | |
1658 | int err; | |
1659 | ||
1660 | if (orphan && inode->i_nlink) | |
1661 | ext3_orphan_del(handle, inode); | |
1662 | if (orphan && ret > 0) { | |
1663 | loff_t end = offset + ret; | |
1664 | if (end > inode->i_size) { | |
1665 | ei->i_disksize = end; | |
1666 | i_size_write(inode, end); | |
1667 | /* | |
1668 | * We're going to return a positive `ret' | |
1669 | * here due to non-zero-length I/O, so there's | |
1670 | * no way of reporting error returns from | |
1671 | * ext3_mark_inode_dirty() to userspace. So | |
1672 | * ignore it. | |
1673 | */ | |
1674 | ext3_mark_inode_dirty(handle, inode); | |
1675 | } | |
1676 | } | |
1677 | err = ext3_journal_stop(handle); | |
1678 | if (ret == 0) | |
1679 | ret = err; | |
1680 | } | |
1681 | out: | |
1682 | return ret; | |
1683 | } | |
1684 | ||
1685 | /* | |
1686 | * Pages can be marked dirty completely asynchronously from ext3's journalling | |
1687 | * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do | |
1688 | * much here because ->set_page_dirty is called under VFS locks. The page is | |
1689 | * not necessarily locked. | |
1690 | * | |
1691 | * We cannot just dirty the page and leave attached buffers clean, because the | |
1692 | * buffers' dirty state is "definitive". We cannot just set the buffers dirty | |
1693 | * or jbddirty because all the journalling code will explode. | |
1694 | * | |
1695 | * So what we do is to mark the page "pending dirty" and next time writepage | |
1696 | * is called, propagate that into the buffers appropriately. | |
1697 | */ | |
1698 | static int ext3_journalled_set_page_dirty(struct page *page) | |
1699 | { | |
1700 | SetPageChecked(page); | |
1701 | return __set_page_dirty_nobuffers(page); | |
1702 | } | |
1703 | ||
f5e54d6e | 1704 | static const struct address_space_operations ext3_ordered_aops = { |
1da177e4 LT |
1705 | .readpage = ext3_readpage, |
1706 | .readpages = ext3_readpages, | |
1707 | .writepage = ext3_ordered_writepage, | |
1708 | .sync_page = block_sync_page, | |
1709 | .prepare_write = ext3_prepare_write, | |
1710 | .commit_write = ext3_ordered_commit_write, | |
1711 | .bmap = ext3_bmap, | |
1712 | .invalidatepage = ext3_invalidatepage, | |
1713 | .releasepage = ext3_releasepage, | |
1714 | .direct_IO = ext3_direct_IO, | |
e965f963 | 1715 | .migratepage = buffer_migrate_page, |
1da177e4 LT |
1716 | }; |
1717 | ||
f5e54d6e | 1718 | static const struct address_space_operations ext3_writeback_aops = { |
1da177e4 LT |
1719 | .readpage = ext3_readpage, |
1720 | .readpages = ext3_readpages, | |
1721 | .writepage = ext3_writeback_writepage, | |
1da177e4 LT |
1722 | .sync_page = block_sync_page, |
1723 | .prepare_write = ext3_prepare_write, | |
1724 | .commit_write = ext3_writeback_commit_write, | |
1725 | .bmap = ext3_bmap, | |
1726 | .invalidatepage = ext3_invalidatepage, | |
1727 | .releasepage = ext3_releasepage, | |
1728 | .direct_IO = ext3_direct_IO, | |
e965f963 | 1729 | .migratepage = buffer_migrate_page, |
1da177e4 LT |
1730 | }; |
1731 | ||
f5e54d6e | 1732 | static const struct address_space_operations ext3_journalled_aops = { |
1da177e4 LT |
1733 | .readpage = ext3_readpage, |
1734 | .readpages = ext3_readpages, | |
1735 | .writepage = ext3_journalled_writepage, | |
1736 | .sync_page = block_sync_page, | |
1737 | .prepare_write = ext3_prepare_write, | |
1738 | .commit_write = ext3_journalled_commit_write, | |
1739 | .set_page_dirty = ext3_journalled_set_page_dirty, | |
1740 | .bmap = ext3_bmap, | |
1741 | .invalidatepage = ext3_invalidatepage, | |
1742 | .releasepage = ext3_releasepage, | |
1743 | }; | |
1744 | ||
1745 | void ext3_set_aops(struct inode *inode) | |
1746 | { | |
1747 | if (ext3_should_order_data(inode)) | |
1748 | inode->i_mapping->a_ops = &ext3_ordered_aops; | |
1749 | else if (ext3_should_writeback_data(inode)) | |
1750 | inode->i_mapping->a_ops = &ext3_writeback_aops; | |
1751 | else | |
1752 | inode->i_mapping->a_ops = &ext3_journalled_aops; | |
1753 | } | |
1754 | ||
1755 | /* | |
1756 | * ext3_block_truncate_page() zeroes out a mapping from file offset `from' | |
1757 | * up to the end of the block which corresponds to `from'. | |
1758 | * This required during truncate. We need to physically zero the tail end | |
1759 | * of that block so it doesn't yield old data if the file is later grown. | |
1760 | */ | |
1761 | static int ext3_block_truncate_page(handle_t *handle, struct page *page, | |
1762 | struct address_space *mapping, loff_t from) | |
1763 | { | |
43d23f90 | 1764 | ext3_fsblk_t index = from >> PAGE_CACHE_SHIFT; |
1da177e4 LT |
1765 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
1766 | unsigned blocksize, iblock, length, pos; | |
1767 | struct inode *inode = mapping->host; | |
1768 | struct buffer_head *bh; | |
1769 | int err = 0; | |
1da177e4 LT |
1770 | |
1771 | blocksize = inode->i_sb->s_blocksize; | |
1772 | length = blocksize - (offset & (blocksize - 1)); | |
1773 | iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
1774 | ||
1775 | /* | |
1776 | * For "nobh" option, we can only work if we don't need to | |
1777 | * read-in the page - otherwise we create buffers to do the IO. | |
1778 | */ | |
cd6ef84e BP |
1779 | if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && |
1780 | ext3_should_writeback_data(inode) && PageUptodate(page)) { | |
0c11d7a9 | 1781 | zero_user_page(page, offset, length, KM_USER0); |
cd6ef84e BP |
1782 | set_page_dirty(page); |
1783 | goto unlock; | |
1da177e4 LT |
1784 | } |
1785 | ||
1786 | if (!page_has_buffers(page)) | |
1787 | create_empty_buffers(page, blocksize, 0); | |
1788 | ||
1789 | /* Find the buffer that contains "offset" */ | |
1790 | bh = page_buffers(page); | |
1791 | pos = blocksize; | |
1792 | while (offset >= pos) { | |
1793 | bh = bh->b_this_page; | |
1794 | iblock++; | |
1795 | pos += blocksize; | |
1796 | } | |
1797 | ||
1798 | err = 0; | |
1799 | if (buffer_freed(bh)) { | |
1800 | BUFFER_TRACE(bh, "freed: skip"); | |
1801 | goto unlock; | |
1802 | } | |
1803 | ||
1804 | if (!buffer_mapped(bh)) { | |
1805 | BUFFER_TRACE(bh, "unmapped"); | |
1806 | ext3_get_block(inode, iblock, bh, 0); | |
1807 | /* unmapped? It's a hole - nothing to do */ | |
1808 | if (!buffer_mapped(bh)) { | |
1809 | BUFFER_TRACE(bh, "still unmapped"); | |
1810 | goto unlock; | |
1811 | } | |
1812 | } | |
1813 | ||
1814 | /* Ok, it's mapped. Make sure it's up-to-date */ | |
1815 | if (PageUptodate(page)) | |
1816 | set_buffer_uptodate(bh); | |
1817 | ||
1818 | if (!buffer_uptodate(bh)) { | |
1819 | err = -EIO; | |
1820 | ll_rw_block(READ, 1, &bh); | |
1821 | wait_on_buffer(bh); | |
1822 | /* Uhhuh. Read error. Complain and punt. */ | |
1823 | if (!buffer_uptodate(bh)) | |
1824 | goto unlock; | |
1825 | } | |
1826 | ||
1827 | if (ext3_should_journal_data(inode)) { | |
1828 | BUFFER_TRACE(bh, "get write access"); | |
1829 | err = ext3_journal_get_write_access(handle, bh); | |
1830 | if (err) | |
1831 | goto unlock; | |
1832 | } | |
1833 | ||
0c11d7a9 | 1834 | zero_user_page(page, offset, length, KM_USER0); |
1da177e4 LT |
1835 | BUFFER_TRACE(bh, "zeroed end of block"); |
1836 | ||
1837 | err = 0; | |
1838 | if (ext3_should_journal_data(inode)) { | |
1839 | err = ext3_journal_dirty_metadata(handle, bh); | |
1840 | } else { | |
1841 | if (ext3_should_order_data(inode)) | |
1842 | err = ext3_journal_dirty_data(handle, bh); | |
1843 | mark_buffer_dirty(bh); | |
1844 | } | |
1845 | ||
1846 | unlock: | |
1847 | unlock_page(page); | |
1848 | page_cache_release(page); | |
1849 | return err; | |
1850 | } | |
1851 | ||
1852 | /* | |
1853 | * Probably it should be a library function... search for first non-zero word | |
1854 | * or memcmp with zero_page, whatever is better for particular architecture. | |
1855 | * Linus? | |
1856 | */ | |
1857 | static inline int all_zeroes(__le32 *p, __le32 *q) | |
1858 | { | |
1859 | while (p < q) | |
1860 | if (*p++) | |
1861 | return 0; | |
1862 | return 1; | |
1863 | } | |
1864 | ||
1865 | /** | |
1866 | * ext3_find_shared - find the indirect blocks for partial truncation. | |
1867 | * @inode: inode in question | |
1868 | * @depth: depth of the affected branch | |
1869 | * @offsets: offsets of pointers in that branch (see ext3_block_to_path) | |
1870 | * @chain: place to store the pointers to partial indirect blocks | |
1871 | * @top: place to the (detached) top of branch | |
1872 | * | |
1873 | * This is a helper function used by ext3_truncate(). | |
1874 | * | |
1875 | * When we do truncate() we may have to clean the ends of several | |
1876 | * indirect blocks but leave the blocks themselves alive. Block is | |
1877 | * partially truncated if some data below the new i_size is refered | |
1878 | * from it (and it is on the path to the first completely truncated | |
1879 | * data block, indeed). We have to free the top of that path along | |
1880 | * with everything to the right of the path. Since no allocation | |
1881 | * past the truncation point is possible until ext3_truncate() | |
1882 | * finishes, we may safely do the latter, but top of branch may | |
1883 | * require special attention - pageout below the truncation point | |
1884 | * might try to populate it. | |
1885 | * | |
1886 | * We atomically detach the top of branch from the tree, store the | |
1887 | * block number of its root in *@top, pointers to buffer_heads of | |
1888 | * partially truncated blocks - in @chain[].bh and pointers to | |
1889 | * their last elements that should not be removed - in | |
1890 | * @chain[].p. Return value is the pointer to last filled element | |
1891 | * of @chain. | |
1892 | * | |
1893 | * The work left to caller to do the actual freeing of subtrees: | |
1894 | * a) free the subtree starting from *@top | |
1895 | * b) free the subtrees whose roots are stored in | |
1896 | * (@chain[i].p+1 .. end of @chain[i].bh->b_data) | |
1897 | * c) free the subtrees growing from the inode past the @chain[0]. | |
1898 | * (no partially truncated stuff there). */ | |
1899 | ||
d6859bfc AM |
1900 | static Indirect *ext3_find_shared(struct inode *inode, int depth, |
1901 | int offsets[4], Indirect chain[4], __le32 *top) | |
1da177e4 LT |
1902 | { |
1903 | Indirect *partial, *p; | |
1904 | int k, err; | |
1905 | ||
1906 | *top = 0; | |
1907 | /* Make k index the deepest non-null offest + 1 */ | |
1908 | for (k = depth; k > 1 && !offsets[k-1]; k--) | |
1909 | ; | |
1910 | partial = ext3_get_branch(inode, k, offsets, chain, &err); | |
1911 | /* Writer: pointers */ | |
1912 | if (!partial) | |
1913 | partial = chain + k-1; | |
1914 | /* | |
1915 | * If the branch acquired continuation since we've looked at it - | |
1916 | * fine, it should all survive and (new) top doesn't belong to us. | |
1917 | */ | |
1918 | if (!partial->key && *partial->p) | |
1919 | /* Writer: end */ | |
1920 | goto no_top; | |
1921 | for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--) | |
1922 | ; | |
1923 | /* | |
1924 | * OK, we've found the last block that must survive. The rest of our | |
1925 | * branch should be detached before unlocking. However, if that rest | |
1926 | * of branch is all ours and does not grow immediately from the inode | |
1927 | * it's easier to cheat and just decrement partial->p. | |
1928 | */ | |
1929 | if (p == chain + k - 1 && p > chain) { | |
1930 | p->p--; | |
1931 | } else { | |
1932 | *top = *p->p; | |
1933 | /* Nope, don't do this in ext3. Must leave the tree intact */ | |
1934 | #if 0 | |
1935 | *p->p = 0; | |
1936 | #endif | |
1937 | } | |
1938 | /* Writer: end */ | |
1939 | ||
d6859bfc | 1940 | while(partial > p) { |
1da177e4 LT |
1941 | brelse(partial->bh); |
1942 | partial--; | |
1943 | } | |
1944 | no_top: | |
1945 | return partial; | |
1946 | } | |
1947 | ||
1948 | /* | |
1949 | * Zero a number of block pointers in either an inode or an indirect block. | |
1950 | * If we restart the transaction we must again get write access to the | |
1951 | * indirect block for further modification. | |
1952 | * | |
1953 | * We release `count' blocks on disk, but (last - first) may be greater | |
1954 | * than `count' because there can be holes in there. | |
1955 | */ | |
d6859bfc | 1956 | static void ext3_clear_blocks(handle_t *handle, struct inode *inode, |
43d23f90 | 1957 | struct buffer_head *bh, ext3_fsblk_t block_to_free, |
d6859bfc | 1958 | unsigned long count, __le32 *first, __le32 *last) |
1da177e4 LT |
1959 | { |
1960 | __le32 *p; | |
1961 | if (try_to_extend_transaction(handle, inode)) { | |
1962 | if (bh) { | |
1963 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
1964 | ext3_journal_dirty_metadata(handle, bh); | |
1965 | } | |
1966 | ext3_mark_inode_dirty(handle, inode); | |
1967 | ext3_journal_test_restart(handle, inode); | |
1968 | if (bh) { | |
1969 | BUFFER_TRACE(bh, "retaking write access"); | |
1970 | ext3_journal_get_write_access(handle, bh); | |
1971 | } | |
1972 | } | |
1973 | ||
1974 | /* | |
1975 | * Any buffers which are on the journal will be in memory. We find | |
1976 | * them on the hash table so journal_revoke() will run journal_forget() | |
1977 | * on them. We've already detached each block from the file, so | |
1978 | * bforget() in journal_forget() should be safe. | |
1979 | * | |
1980 | * AKPM: turn on bforget in journal_forget()!!! | |
1981 | */ | |
1982 | for (p = first; p < last; p++) { | |
1983 | u32 nr = le32_to_cpu(*p); | |
1984 | if (nr) { | |
1985 | struct buffer_head *bh; | |
1986 | ||
1987 | *p = 0; | |
1988 | bh = sb_find_get_block(inode->i_sb, nr); | |
1989 | ext3_forget(handle, 0, inode, bh, nr); | |
1990 | } | |
1991 | } | |
1992 | ||
1993 | ext3_free_blocks(handle, inode, block_to_free, count); | |
1994 | } | |
1995 | ||
1996 | /** | |
1997 | * ext3_free_data - free a list of data blocks | |
1998 | * @handle: handle for this transaction | |
1999 | * @inode: inode we are dealing with | |
2000 | * @this_bh: indirect buffer_head which contains *@first and *@last | |
2001 | * @first: array of block numbers | |
2002 | * @last: points immediately past the end of array | |
2003 | * | |
2004 | * We are freeing all blocks refered from that array (numbers are stored as | |
2005 | * little-endian 32-bit) and updating @inode->i_blocks appropriately. | |
2006 | * | |
2007 | * We accumulate contiguous runs of blocks to free. Conveniently, if these | |
2008 | * blocks are contiguous then releasing them at one time will only affect one | |
2009 | * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't | |
2010 | * actually use a lot of journal space. | |
2011 | * | |
2012 | * @this_bh will be %NULL if @first and @last point into the inode's direct | |
2013 | * block pointers. | |
2014 | */ | |
2015 | static void ext3_free_data(handle_t *handle, struct inode *inode, | |
2016 | struct buffer_head *this_bh, | |
2017 | __le32 *first, __le32 *last) | |
2018 | { | |
43d23f90 | 2019 | ext3_fsblk_t block_to_free = 0; /* Starting block # of a run */ |
ae6ddcc5 | 2020 | unsigned long count = 0; /* Number of blocks in the run */ |
1da177e4 LT |
2021 | __le32 *block_to_free_p = NULL; /* Pointer into inode/ind |
2022 | corresponding to | |
2023 | block_to_free */ | |
43d23f90 | 2024 | ext3_fsblk_t nr; /* Current block # */ |
1da177e4 LT |
2025 | __le32 *p; /* Pointer into inode/ind |
2026 | for current block */ | |
2027 | int err; | |
2028 | ||
2029 | if (this_bh) { /* For indirect block */ | |
2030 | BUFFER_TRACE(this_bh, "get_write_access"); | |
2031 | err = ext3_journal_get_write_access(handle, this_bh); | |
2032 | /* Important: if we can't update the indirect pointers | |
2033 | * to the blocks, we can't free them. */ | |
2034 | if (err) | |
2035 | return; | |
2036 | } | |
2037 | ||
2038 | for (p = first; p < last; p++) { | |
2039 | nr = le32_to_cpu(*p); | |
2040 | if (nr) { | |
2041 | /* accumulate blocks to free if they're contiguous */ | |
2042 | if (count == 0) { | |
2043 | block_to_free = nr; | |
2044 | block_to_free_p = p; | |
2045 | count = 1; | |
2046 | } else if (nr == block_to_free + count) { | |
2047 | count++; | |
2048 | } else { | |
ae6ddcc5 | 2049 | ext3_clear_blocks(handle, inode, this_bh, |
1da177e4 LT |
2050 | block_to_free, |
2051 | count, block_to_free_p, p); | |
2052 | block_to_free = nr; | |
2053 | block_to_free_p = p; | |
2054 | count = 1; | |
2055 | } | |
2056 | } | |
2057 | } | |
2058 | ||
2059 | if (count > 0) | |
2060 | ext3_clear_blocks(handle, inode, this_bh, block_to_free, | |
2061 | count, block_to_free_p, p); | |
2062 | ||
2063 | if (this_bh) { | |
2064 | BUFFER_TRACE(this_bh, "call ext3_journal_dirty_metadata"); | |
2065 | ext3_journal_dirty_metadata(handle, this_bh); | |
2066 | } | |
2067 | } | |
2068 | ||
2069 | /** | |
2070 | * ext3_free_branches - free an array of branches | |
2071 | * @handle: JBD handle for this transaction | |
2072 | * @inode: inode we are dealing with | |
2073 | * @parent_bh: the buffer_head which contains *@first and *@last | |
2074 | * @first: array of block numbers | |
2075 | * @last: pointer immediately past the end of array | |
2076 | * @depth: depth of the branches to free | |
2077 | * | |
2078 | * We are freeing all blocks refered from these branches (numbers are | |
2079 | * stored as little-endian 32-bit) and updating @inode->i_blocks | |
2080 | * appropriately. | |
2081 | */ | |
2082 | static void ext3_free_branches(handle_t *handle, struct inode *inode, | |
2083 | struct buffer_head *parent_bh, | |
2084 | __le32 *first, __le32 *last, int depth) | |
2085 | { | |
43d23f90 | 2086 | ext3_fsblk_t nr; |
1da177e4 LT |
2087 | __le32 *p; |
2088 | ||
2089 | if (is_handle_aborted(handle)) | |
2090 | return; | |
2091 | ||
2092 | if (depth--) { | |
2093 | struct buffer_head *bh; | |
2094 | int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
2095 | p = last; | |
2096 | while (--p >= first) { | |
2097 | nr = le32_to_cpu(*p); | |
2098 | if (!nr) | |
2099 | continue; /* A hole */ | |
2100 | ||
2101 | /* Go read the buffer for the next level down */ | |
2102 | bh = sb_bread(inode->i_sb, nr); | |
2103 | ||
2104 | /* | |
2105 | * A read failure? Report error and clear slot | |
2106 | * (should be rare). | |
2107 | */ | |
2108 | if (!bh) { | |
2109 | ext3_error(inode->i_sb, "ext3_free_branches", | |
eee194e7 | 2110 | "Read failure, inode=%lu, block="E3FSBLK, |
1da177e4 LT |
2111 | inode->i_ino, nr); |
2112 | continue; | |
2113 | } | |
2114 | ||
2115 | /* This zaps the entire block. Bottom up. */ | |
2116 | BUFFER_TRACE(bh, "free child branches"); | |
2117 | ext3_free_branches(handle, inode, bh, | |
2118 | (__le32*)bh->b_data, | |
2119 | (__le32*)bh->b_data + addr_per_block, | |
2120 | depth); | |
2121 | ||
2122 | /* | |
2123 | * We've probably journalled the indirect block several | |
2124 | * times during the truncate. But it's no longer | |
2125 | * needed and we now drop it from the transaction via | |
2126 | * journal_revoke(). | |
2127 | * | |
2128 | * That's easy if it's exclusively part of this | |
2129 | * transaction. But if it's part of the committing | |
2130 | * transaction then journal_forget() will simply | |
2131 | * brelse() it. That means that if the underlying | |
2132 | * block is reallocated in ext3_get_block(), | |
2133 | * unmap_underlying_metadata() will find this block | |
2134 | * and will try to get rid of it. damn, damn. | |
2135 | * | |
2136 | * If this block has already been committed to the | |
2137 | * journal, a revoke record will be written. And | |
2138 | * revoke records must be emitted *before* clearing | |
2139 | * this block's bit in the bitmaps. | |
2140 | */ | |
2141 | ext3_forget(handle, 1, inode, bh, bh->b_blocknr); | |
2142 | ||
2143 | /* | |
2144 | * Everything below this this pointer has been | |
2145 | * released. Now let this top-of-subtree go. | |
2146 | * | |
2147 | * We want the freeing of this indirect block to be | |
2148 | * atomic in the journal with the updating of the | |
2149 | * bitmap block which owns it. So make some room in | |
2150 | * the journal. | |
2151 | * | |
2152 | * We zero the parent pointer *after* freeing its | |
2153 | * pointee in the bitmaps, so if extend_transaction() | |
2154 | * for some reason fails to put the bitmap changes and | |
2155 | * the release into the same transaction, recovery | |
2156 | * will merely complain about releasing a free block, | |
2157 | * rather than leaking blocks. | |
2158 | */ | |
2159 | if (is_handle_aborted(handle)) | |
2160 | return; | |
2161 | if (try_to_extend_transaction(handle, inode)) { | |
2162 | ext3_mark_inode_dirty(handle, inode); | |
2163 | ext3_journal_test_restart(handle, inode); | |
2164 | } | |
2165 | ||
2166 | ext3_free_blocks(handle, inode, nr, 1); | |
2167 | ||
2168 | if (parent_bh) { | |
2169 | /* | |
2170 | * The block which we have just freed is | |
2171 | * pointed to by an indirect block: journal it | |
2172 | */ | |
2173 | BUFFER_TRACE(parent_bh, "get_write_access"); | |
2174 | if (!ext3_journal_get_write_access(handle, | |
2175 | parent_bh)){ | |
2176 | *p = 0; | |
2177 | BUFFER_TRACE(parent_bh, | |
2178 | "call ext3_journal_dirty_metadata"); | |
ae6ddcc5 | 2179 | ext3_journal_dirty_metadata(handle, |
1da177e4 LT |
2180 | parent_bh); |
2181 | } | |
2182 | } | |
2183 | } | |
2184 | } else { | |
2185 | /* We have reached the bottom of the tree. */ | |
2186 | BUFFER_TRACE(parent_bh, "free data blocks"); | |
2187 | ext3_free_data(handle, inode, parent_bh, first, last); | |
2188 | } | |
2189 | } | |
2190 | ||
2191 | /* | |
2192 | * ext3_truncate() | |
2193 | * | |
2194 | * We block out ext3_get_block() block instantiations across the entire | |
2195 | * transaction, and VFS/VM ensures that ext3_truncate() cannot run | |
2196 | * simultaneously on behalf of the same inode. | |
2197 | * | |
2198 | * As we work through the truncate and commmit bits of it to the journal there | |
2199 | * is one core, guiding principle: the file's tree must always be consistent on | |
2200 | * disk. We must be able to restart the truncate after a crash. | |
2201 | * | |
2202 | * The file's tree may be transiently inconsistent in memory (although it | |
2203 | * probably isn't), but whenever we close off and commit a journal transaction, | |
2204 | * the contents of (the filesystem + the journal) must be consistent and | |
2205 | * restartable. It's pretty simple, really: bottom up, right to left (although | |
2206 | * left-to-right works OK too). | |
2207 | * | |
2208 | * Note that at recovery time, journal replay occurs *before* the restart of | |
2209 | * truncate against the orphan inode list. | |
2210 | * | |
2211 | * The committed inode has the new, desired i_size (which is the same as | |
2212 | * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see | |
2213 | * that this inode's truncate did not complete and it will again call | |
2214 | * ext3_truncate() to have another go. So there will be instantiated blocks | |
2215 | * to the right of the truncation point in a crashed ext3 filesystem. But | |
2216 | * that's fine - as long as they are linked from the inode, the post-crash | |
2217 | * ext3_truncate() run will find them and release them. | |
2218 | */ | |
d6859bfc | 2219 | void ext3_truncate(struct inode *inode) |
1da177e4 LT |
2220 | { |
2221 | handle_t *handle; | |
2222 | struct ext3_inode_info *ei = EXT3_I(inode); | |
2223 | __le32 *i_data = ei->i_data; | |
2224 | int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb); | |
2225 | struct address_space *mapping = inode->i_mapping; | |
2226 | int offsets[4]; | |
2227 | Indirect chain[4]; | |
2228 | Indirect *partial; | |
2229 | __le32 nr = 0; | |
2230 | int n; | |
2231 | long last_block; | |
2232 | unsigned blocksize = inode->i_sb->s_blocksize; | |
2233 | struct page *page; | |
2234 | ||
2235 | if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || | |
2236 | S_ISLNK(inode->i_mode))) | |
2237 | return; | |
2238 | if (ext3_inode_is_fast_symlink(inode)) | |
2239 | return; | |
2240 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | |
2241 | return; | |
2242 | ||
2243 | /* | |
2244 | * We have to lock the EOF page here, because lock_page() nests | |
2245 | * outside journal_start(). | |
2246 | */ | |
2247 | if ((inode->i_size & (blocksize - 1)) == 0) { | |
2248 | /* Block boundary? Nothing to do */ | |
2249 | page = NULL; | |
2250 | } else { | |
2251 | page = grab_cache_page(mapping, | |
2252 | inode->i_size >> PAGE_CACHE_SHIFT); | |
2253 | if (!page) | |
2254 | return; | |
2255 | } | |
2256 | ||
2257 | handle = start_transaction(inode); | |
2258 | if (IS_ERR(handle)) { | |
2259 | if (page) { | |
2260 | clear_highpage(page); | |
2261 | flush_dcache_page(page); | |
2262 | unlock_page(page); | |
2263 | page_cache_release(page); | |
2264 | } | |
2265 | return; /* AKPM: return what? */ | |
2266 | } | |
2267 | ||
2268 | last_block = (inode->i_size + blocksize-1) | |
2269 | >> EXT3_BLOCK_SIZE_BITS(inode->i_sb); | |
2270 | ||
2271 | if (page) | |
2272 | ext3_block_truncate_page(handle, page, mapping, inode->i_size); | |
2273 | ||
2274 | n = ext3_block_to_path(inode, last_block, offsets, NULL); | |
2275 | if (n == 0) | |
2276 | goto out_stop; /* error */ | |
2277 | ||
2278 | /* | |
2279 | * OK. This truncate is going to happen. We add the inode to the | |
2280 | * orphan list, so that if this truncate spans multiple transactions, | |
2281 | * and we crash, we will resume the truncate when the filesystem | |
2282 | * recovers. It also marks the inode dirty, to catch the new size. | |
2283 | * | |
2284 | * Implication: the file must always be in a sane, consistent | |
2285 | * truncatable state while each transaction commits. | |
2286 | */ | |
2287 | if (ext3_orphan_add(handle, inode)) | |
2288 | goto out_stop; | |
2289 | ||
2290 | /* | |
2291 | * The orphan list entry will now protect us from any crash which | |
2292 | * occurs before the truncate completes, so it is now safe to propagate | |
2293 | * the new, shorter inode size (held for now in i_size) into the | |
2294 | * on-disk inode. We do this via i_disksize, which is the value which | |
2295 | * ext3 *really* writes onto the disk inode. | |
2296 | */ | |
2297 | ei->i_disksize = inode->i_size; | |
2298 | ||
2299 | /* | |
2300 | * From here we block out all ext3_get_block() callers who want to | |
2301 | * modify the block allocation tree. | |
2302 | */ | |
97461518 | 2303 | mutex_lock(&ei->truncate_mutex); |
1da177e4 LT |
2304 | |
2305 | if (n == 1) { /* direct blocks */ | |
2306 | ext3_free_data(handle, inode, NULL, i_data+offsets[0], | |
2307 | i_data + EXT3_NDIR_BLOCKS); | |
2308 | goto do_indirects; | |
2309 | } | |
2310 | ||
2311 | partial = ext3_find_shared(inode, n, offsets, chain, &nr); | |
2312 | /* Kill the top of shared branch (not detached) */ | |
2313 | if (nr) { | |
2314 | if (partial == chain) { | |
2315 | /* Shared branch grows from the inode */ | |
2316 | ext3_free_branches(handle, inode, NULL, | |
2317 | &nr, &nr+1, (chain+n-1) - partial); | |
2318 | *partial->p = 0; | |
2319 | /* | |
2320 | * We mark the inode dirty prior to restart, | |
2321 | * and prior to stop. No need for it here. | |
2322 | */ | |
2323 | } else { | |
2324 | /* Shared branch grows from an indirect block */ | |
2325 | BUFFER_TRACE(partial->bh, "get_write_access"); | |
2326 | ext3_free_branches(handle, inode, partial->bh, | |
2327 | partial->p, | |
2328 | partial->p+1, (chain+n-1) - partial); | |
2329 | } | |
2330 | } | |
2331 | /* Clear the ends of indirect blocks on the shared branch */ | |
2332 | while (partial > chain) { | |
2333 | ext3_free_branches(handle, inode, partial->bh, partial->p + 1, | |
2334 | (__le32*)partial->bh->b_data+addr_per_block, | |
2335 | (chain+n-1) - partial); | |
2336 | BUFFER_TRACE(partial->bh, "call brelse"); | |
2337 | brelse (partial->bh); | |
2338 | partial--; | |
2339 | } | |
2340 | do_indirects: | |
2341 | /* Kill the remaining (whole) subtrees */ | |
2342 | switch (offsets[0]) { | |
d6859bfc AM |
2343 | default: |
2344 | nr = i_data[EXT3_IND_BLOCK]; | |
2345 | if (nr) { | |
2346 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 1); | |
2347 | i_data[EXT3_IND_BLOCK] = 0; | |
2348 | } | |
2349 | case EXT3_IND_BLOCK: | |
2350 | nr = i_data[EXT3_DIND_BLOCK]; | |
2351 | if (nr) { | |
2352 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 2); | |
2353 | i_data[EXT3_DIND_BLOCK] = 0; | |
2354 | } | |
2355 | case EXT3_DIND_BLOCK: | |
2356 | nr = i_data[EXT3_TIND_BLOCK]; | |
2357 | if (nr) { | |
2358 | ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 3); | |
2359 | i_data[EXT3_TIND_BLOCK] = 0; | |
2360 | } | |
2361 | case EXT3_TIND_BLOCK: | |
2362 | ; | |
1da177e4 LT |
2363 | } |
2364 | ||
2365 | ext3_discard_reservation(inode); | |
2366 | ||
97461518 | 2367 | mutex_unlock(&ei->truncate_mutex); |
1da177e4 LT |
2368 | inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; |
2369 | ext3_mark_inode_dirty(handle, inode); | |
2370 | ||
d6859bfc AM |
2371 | /* |
2372 | * In a multi-transaction truncate, we only make the final transaction | |
2373 | * synchronous | |
2374 | */ | |
1da177e4 LT |
2375 | if (IS_SYNC(inode)) |
2376 | handle->h_sync = 1; | |
2377 | out_stop: | |
2378 | /* | |
2379 | * If this was a simple ftruncate(), and the file will remain alive | |
2380 | * then we need to clear up the orphan record which we created above. | |
2381 | * However, if this was a real unlink then we were called by | |
2382 | * ext3_delete_inode(), and we allow that function to clean up the | |
2383 | * orphan info for us. | |
2384 | */ | |
2385 | if (inode->i_nlink) | |
2386 | ext3_orphan_del(handle, inode); | |
2387 | ||
2388 | ext3_journal_stop(handle); | |
2389 | } | |
2390 | ||
43d23f90 | 2391 | static ext3_fsblk_t ext3_get_inode_block(struct super_block *sb, |
1da177e4 LT |
2392 | unsigned long ino, struct ext3_iloc *iloc) |
2393 | { | |
2394 | unsigned long desc, group_desc, block_group; | |
43d23f90 MC |
2395 | unsigned long offset; |
2396 | ext3_fsblk_t block; | |
1da177e4 LT |
2397 | struct buffer_head *bh; |
2398 | struct ext3_group_desc * gdp; | |
2399 | ||
2ccb48eb NB |
2400 | if (!ext3_valid_inum(sb, ino)) { |
2401 | /* | |
2402 | * This error is already checked for in namei.c unless we are | |
2403 | * looking at an NFS filehandle, in which case no error | |
2404 | * report is needed | |
2405 | */ | |
1da177e4 LT |
2406 | return 0; |
2407 | } | |
2ccb48eb | 2408 | |
1da177e4 LT |
2409 | block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb); |
2410 | if (block_group >= EXT3_SB(sb)->s_groups_count) { | |
d6859bfc | 2411 | ext3_error(sb,"ext3_get_inode_block","group >= groups count"); |
1da177e4 LT |
2412 | return 0; |
2413 | } | |
2414 | smp_rmb(); | |
2415 | group_desc = block_group >> EXT3_DESC_PER_BLOCK_BITS(sb); | |
2416 | desc = block_group & (EXT3_DESC_PER_BLOCK(sb) - 1); | |
2417 | bh = EXT3_SB(sb)->s_group_desc[group_desc]; | |
2418 | if (!bh) { | |
2419 | ext3_error (sb, "ext3_get_inode_block", | |
2420 | "Descriptor not loaded"); | |
2421 | return 0; | |
2422 | } | |
2423 | ||
d6859bfc | 2424 | gdp = (struct ext3_group_desc *)bh->b_data; |
1da177e4 LT |
2425 | /* |
2426 | * Figure out the offset within the block group inode table | |
2427 | */ | |
2428 | offset = ((ino - 1) % EXT3_INODES_PER_GROUP(sb)) * | |
2429 | EXT3_INODE_SIZE(sb); | |
2430 | block = le32_to_cpu(gdp[desc].bg_inode_table) + | |
2431 | (offset >> EXT3_BLOCK_SIZE_BITS(sb)); | |
2432 | ||
2433 | iloc->block_group = block_group; | |
2434 | iloc->offset = offset & (EXT3_BLOCK_SIZE(sb) - 1); | |
2435 | return block; | |
2436 | } | |
2437 | ||
2438 | /* | |
2439 | * ext3_get_inode_loc returns with an extra refcount against the inode's | |
2440 | * underlying buffer_head on success. If 'in_mem' is true, we have all | |
2441 | * data in memory that is needed to recreate the on-disk version of this | |
2442 | * inode. | |
2443 | */ | |
2444 | static int __ext3_get_inode_loc(struct inode *inode, | |
2445 | struct ext3_iloc *iloc, int in_mem) | |
2446 | { | |
43d23f90 | 2447 | ext3_fsblk_t block; |
1da177e4 LT |
2448 | struct buffer_head *bh; |
2449 | ||
2450 | block = ext3_get_inode_block(inode->i_sb, inode->i_ino, iloc); | |
2451 | if (!block) | |
2452 | return -EIO; | |
2453 | ||
2454 | bh = sb_getblk(inode->i_sb, block); | |
2455 | if (!bh) { | |
2456 | ext3_error (inode->i_sb, "ext3_get_inode_loc", | |
2457 | "unable to read inode block - " | |
43d23f90 MC |
2458 | "inode=%lu, block="E3FSBLK, |
2459 | inode->i_ino, block); | |
1da177e4 LT |
2460 | return -EIO; |
2461 | } | |
2462 | if (!buffer_uptodate(bh)) { | |
2463 | lock_buffer(bh); | |
2464 | if (buffer_uptodate(bh)) { | |
2465 | /* someone brought it uptodate while we waited */ | |
2466 | unlock_buffer(bh); | |
2467 | goto has_buffer; | |
2468 | } | |
2469 | ||
2470 | /* | |
2471 | * If we have all information of the inode in memory and this | |
2472 | * is the only valid inode in the block, we need not read the | |
2473 | * block. | |
2474 | */ | |
2475 | if (in_mem) { | |
2476 | struct buffer_head *bitmap_bh; | |
2477 | struct ext3_group_desc *desc; | |
2478 | int inodes_per_buffer; | |
2479 | int inode_offset, i; | |
2480 | int block_group; | |
2481 | int start; | |
2482 | ||
2483 | block_group = (inode->i_ino - 1) / | |
2484 | EXT3_INODES_PER_GROUP(inode->i_sb); | |
2485 | inodes_per_buffer = bh->b_size / | |
2486 | EXT3_INODE_SIZE(inode->i_sb); | |
2487 | inode_offset = ((inode->i_ino - 1) % | |
2488 | EXT3_INODES_PER_GROUP(inode->i_sb)); | |
2489 | start = inode_offset & ~(inodes_per_buffer - 1); | |
2490 | ||
2491 | /* Is the inode bitmap in cache? */ | |
2492 | desc = ext3_get_group_desc(inode->i_sb, | |
2493 | block_group, NULL); | |
2494 | if (!desc) | |
2495 | goto make_io; | |
2496 | ||
2497 | bitmap_bh = sb_getblk(inode->i_sb, | |
2498 | le32_to_cpu(desc->bg_inode_bitmap)); | |
2499 | if (!bitmap_bh) | |
2500 | goto make_io; | |
2501 | ||
2502 | /* | |
2503 | * If the inode bitmap isn't in cache then the | |
2504 | * optimisation may end up performing two reads instead | |
2505 | * of one, so skip it. | |
2506 | */ | |
2507 | if (!buffer_uptodate(bitmap_bh)) { | |
2508 | brelse(bitmap_bh); | |
2509 | goto make_io; | |
2510 | } | |
2511 | for (i = start; i < start + inodes_per_buffer; i++) { | |
2512 | if (i == inode_offset) | |
2513 | continue; | |
2514 | if (ext3_test_bit(i, bitmap_bh->b_data)) | |
2515 | break; | |
2516 | } | |
2517 | brelse(bitmap_bh); | |
2518 | if (i == start + inodes_per_buffer) { | |
2519 | /* all other inodes are free, so skip I/O */ | |
2520 | memset(bh->b_data, 0, bh->b_size); | |
2521 | set_buffer_uptodate(bh); | |
2522 | unlock_buffer(bh); | |
2523 | goto has_buffer; | |
2524 | } | |
2525 | } | |
2526 | ||
2527 | make_io: | |
2528 | /* | |
2529 | * There are other valid inodes in the buffer, this inode | |
2530 | * has in-inode xattrs, or we don't have this inode in memory. | |
2531 | * Read the block from disk. | |
2532 | */ | |
2533 | get_bh(bh); | |
2534 | bh->b_end_io = end_buffer_read_sync; | |
caa38fb0 | 2535 | submit_bh(READ_META, bh); |
1da177e4 LT |
2536 | wait_on_buffer(bh); |
2537 | if (!buffer_uptodate(bh)) { | |
2538 | ext3_error(inode->i_sb, "ext3_get_inode_loc", | |
2539 | "unable to read inode block - " | |
43d23f90 | 2540 | "inode=%lu, block="E3FSBLK, |
1da177e4 LT |
2541 | inode->i_ino, block); |
2542 | brelse(bh); | |
2543 | return -EIO; | |
2544 | } | |
2545 | } | |
2546 | has_buffer: | |
2547 | iloc->bh = bh; | |
2548 | return 0; | |
2549 | } | |
2550 | ||
2551 | int ext3_get_inode_loc(struct inode *inode, struct ext3_iloc *iloc) | |
2552 | { | |
2553 | /* We have all inode data except xattrs in memory here. */ | |
2554 | return __ext3_get_inode_loc(inode, iloc, | |
2555 | !(EXT3_I(inode)->i_state & EXT3_STATE_XATTR)); | |
2556 | } | |
2557 | ||
2558 | void ext3_set_inode_flags(struct inode *inode) | |
2559 | { | |
2560 | unsigned int flags = EXT3_I(inode)->i_flags; | |
2561 | ||
2562 | inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); | |
2563 | if (flags & EXT3_SYNC_FL) | |
2564 | inode->i_flags |= S_SYNC; | |
2565 | if (flags & EXT3_APPEND_FL) | |
2566 | inode->i_flags |= S_APPEND; | |
2567 | if (flags & EXT3_IMMUTABLE_FL) | |
2568 | inode->i_flags |= S_IMMUTABLE; | |
2569 | if (flags & EXT3_NOATIME_FL) | |
2570 | inode->i_flags |= S_NOATIME; | |
2571 | if (flags & EXT3_DIRSYNC_FL) | |
2572 | inode->i_flags |= S_DIRSYNC; | |
2573 | } | |
2574 | ||
28be5abb JK |
2575 | /* Propagate flags from i_flags to EXT3_I(inode)->i_flags */ |
2576 | void ext3_get_inode_flags(struct ext3_inode_info *ei) | |
2577 | { | |
2578 | unsigned int flags = ei->vfs_inode.i_flags; | |
2579 | ||
2580 | ei->i_flags &= ~(EXT3_SYNC_FL|EXT3_APPEND_FL| | |
2581 | EXT3_IMMUTABLE_FL|EXT3_NOATIME_FL|EXT3_DIRSYNC_FL); | |
2582 | if (flags & S_SYNC) | |
2583 | ei->i_flags |= EXT3_SYNC_FL; | |
2584 | if (flags & S_APPEND) | |
2585 | ei->i_flags |= EXT3_APPEND_FL; | |
2586 | if (flags & S_IMMUTABLE) | |
2587 | ei->i_flags |= EXT3_IMMUTABLE_FL; | |
2588 | if (flags & S_NOATIME) | |
2589 | ei->i_flags |= EXT3_NOATIME_FL; | |
2590 | if (flags & S_DIRSYNC) | |
2591 | ei->i_flags |= EXT3_DIRSYNC_FL; | |
2592 | } | |
2593 | ||
1da177e4 LT |
2594 | void ext3_read_inode(struct inode * inode) |
2595 | { | |
2596 | struct ext3_iloc iloc; | |
2597 | struct ext3_inode *raw_inode; | |
2598 | struct ext3_inode_info *ei = EXT3_I(inode); | |
2599 | struct buffer_head *bh; | |
2600 | int block; | |
2601 | ||
2602 | #ifdef CONFIG_EXT3_FS_POSIX_ACL | |
2603 | ei->i_acl = EXT3_ACL_NOT_CACHED; | |
2604 | ei->i_default_acl = EXT3_ACL_NOT_CACHED; | |
2605 | #endif | |
2606 | ei->i_block_alloc_info = NULL; | |
2607 | ||
2608 | if (__ext3_get_inode_loc(inode, &iloc, 0)) | |
2609 | goto bad_inode; | |
2610 | bh = iloc.bh; | |
2611 | raw_inode = ext3_raw_inode(&iloc); | |
2612 | inode->i_mode = le16_to_cpu(raw_inode->i_mode); | |
2613 | inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); | |
2614 | inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); | |
2615 | if(!(test_opt (inode->i_sb, NO_UID32))) { | |
2616 | inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; | |
2617 | inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; | |
2618 | } | |
2619 | inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); | |
2620 | inode->i_size = le32_to_cpu(raw_inode->i_size); | |
4d7bf11d MR |
2621 | inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime); |
2622 | inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime); | |
2623 | inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime); | |
1da177e4 LT |
2624 | inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0; |
2625 | ||
2626 | ei->i_state = 0; | |
2627 | ei->i_dir_start_lookup = 0; | |
2628 | ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); | |
2629 | /* We now have enough fields to check if the inode was active or not. | |
2630 | * This is needed because nfsd might try to access dead inodes | |
2631 | * the test is that same one that e2fsck uses | |
2632 | * NeilBrown 1999oct15 | |
2633 | */ | |
2634 | if (inode->i_nlink == 0) { | |
2635 | if (inode->i_mode == 0 || | |
2636 | !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ORPHAN_FS)) { | |
2637 | /* this inode is deleted */ | |
2638 | brelse (bh); | |
2639 | goto bad_inode; | |
2640 | } | |
2641 | /* The only unlinked inodes we let through here have | |
2642 | * valid i_mode and are being read by the orphan | |
2643 | * recovery code: that's fine, we're about to complete | |
2644 | * the process of deleting those. */ | |
2645 | } | |
1da177e4 LT |
2646 | inode->i_blocks = le32_to_cpu(raw_inode->i_blocks); |
2647 | ei->i_flags = le32_to_cpu(raw_inode->i_flags); | |
2648 | #ifdef EXT3_FRAGMENTS | |
2649 | ei->i_faddr = le32_to_cpu(raw_inode->i_faddr); | |
2650 | ei->i_frag_no = raw_inode->i_frag; | |
2651 | ei->i_frag_size = raw_inode->i_fsize; | |
2652 | #endif | |
2653 | ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl); | |
2654 | if (!S_ISREG(inode->i_mode)) { | |
2655 | ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl); | |
2656 | } else { | |
2657 | inode->i_size |= | |
2658 | ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32; | |
2659 | } | |
2660 | ei->i_disksize = inode->i_size; | |
2661 | inode->i_generation = le32_to_cpu(raw_inode->i_generation); | |
2662 | ei->i_block_group = iloc.block_group; | |
2663 | /* | |
2664 | * NOTE! The in-memory inode i_data array is in little-endian order | |
2665 | * even on big-endian machines: we do NOT byteswap the block numbers! | |
2666 | */ | |
2667 | for (block = 0; block < EXT3_N_BLOCKS; block++) | |
2668 | ei->i_data[block] = raw_inode->i_block[block]; | |
2669 | INIT_LIST_HEAD(&ei->i_orphan); | |
2670 | ||
2671 | if (inode->i_ino >= EXT3_FIRST_INO(inode->i_sb) + 1 && | |
2672 | EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) { | |
2673 | /* | |
2674 | * When mke2fs creates big inodes it does not zero out | |
2675 | * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE, | |
2676 | * so ignore those first few inodes. | |
2677 | */ | |
2678 | ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); | |
2679 | if (EXT3_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > | |
2680 | EXT3_INODE_SIZE(inode->i_sb)) | |
2681 | goto bad_inode; | |
2682 | if (ei->i_extra_isize == 0) { | |
2683 | /* The extra space is currently unused. Use it. */ | |
2684 | ei->i_extra_isize = sizeof(struct ext3_inode) - | |
2685 | EXT3_GOOD_OLD_INODE_SIZE; | |
2686 | } else { | |
2687 | __le32 *magic = (void *)raw_inode + | |
2688 | EXT3_GOOD_OLD_INODE_SIZE + | |
2689 | ei->i_extra_isize; | |
2690 | if (*magic == cpu_to_le32(EXT3_XATTR_MAGIC)) | |
2691 | ei->i_state |= EXT3_STATE_XATTR; | |
2692 | } | |
2693 | } else | |
2694 | ei->i_extra_isize = 0; | |
2695 | ||
2696 | if (S_ISREG(inode->i_mode)) { | |
2697 | inode->i_op = &ext3_file_inode_operations; | |
2698 | inode->i_fop = &ext3_file_operations; | |
2699 | ext3_set_aops(inode); | |
2700 | } else if (S_ISDIR(inode->i_mode)) { | |
2701 | inode->i_op = &ext3_dir_inode_operations; | |
2702 | inode->i_fop = &ext3_dir_operations; | |
2703 | } else if (S_ISLNK(inode->i_mode)) { | |
2704 | if (ext3_inode_is_fast_symlink(inode)) | |
2705 | inode->i_op = &ext3_fast_symlink_inode_operations; | |
2706 | else { | |
2707 | inode->i_op = &ext3_symlink_inode_operations; | |
2708 | ext3_set_aops(inode); | |
2709 | } | |
2710 | } else { | |
2711 | inode->i_op = &ext3_special_inode_operations; | |
2712 | if (raw_inode->i_block[0]) | |
2713 | init_special_inode(inode, inode->i_mode, | |
2714 | old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); | |
ae6ddcc5 | 2715 | else |
1da177e4 LT |
2716 | init_special_inode(inode, inode->i_mode, |
2717 | new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); | |
2718 | } | |
2719 | brelse (iloc.bh); | |
2720 | ext3_set_inode_flags(inode); | |
2721 | return; | |
2722 | ||
2723 | bad_inode: | |
2724 | make_bad_inode(inode); | |
2725 | return; | |
2726 | } | |
2727 | ||
2728 | /* | |
2729 | * Post the struct inode info into an on-disk inode location in the | |
2730 | * buffer-cache. This gobbles the caller's reference to the | |
2731 | * buffer_head in the inode location struct. | |
2732 | * | |
2733 | * The caller must have write access to iloc->bh. | |
2734 | */ | |
ae6ddcc5 MC |
2735 | static int ext3_do_update_inode(handle_t *handle, |
2736 | struct inode *inode, | |
1da177e4 LT |
2737 | struct ext3_iloc *iloc) |
2738 | { | |
2739 | struct ext3_inode *raw_inode = ext3_raw_inode(iloc); | |
2740 | struct ext3_inode_info *ei = EXT3_I(inode); | |
2741 | struct buffer_head *bh = iloc->bh; | |
2742 | int err = 0, rc, block; | |
2743 | ||
2744 | /* For fields not not tracking in the in-memory inode, | |
2745 | * initialise them to zero for new inodes. */ | |
2746 | if (ei->i_state & EXT3_STATE_NEW) | |
2747 | memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size); | |
2748 | ||
28be5abb | 2749 | ext3_get_inode_flags(ei); |
1da177e4 LT |
2750 | raw_inode->i_mode = cpu_to_le16(inode->i_mode); |
2751 | if(!(test_opt(inode->i_sb, NO_UID32))) { | |
2752 | raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid)); | |
2753 | raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid)); | |
2754 | /* | |
2755 | * Fix up interoperability with old kernels. Otherwise, old inodes get | |
2756 | * re-used with the upper 16 bits of the uid/gid intact | |
2757 | */ | |
2758 | if(!ei->i_dtime) { | |
2759 | raw_inode->i_uid_high = | |
2760 | cpu_to_le16(high_16_bits(inode->i_uid)); | |
2761 | raw_inode->i_gid_high = | |
2762 | cpu_to_le16(high_16_bits(inode->i_gid)); | |
2763 | } else { | |
2764 | raw_inode->i_uid_high = 0; | |
2765 | raw_inode->i_gid_high = 0; | |
2766 | } | |
2767 | } else { | |
2768 | raw_inode->i_uid_low = | |
2769 | cpu_to_le16(fs_high2lowuid(inode->i_uid)); | |
2770 | raw_inode->i_gid_low = | |
2771 | cpu_to_le16(fs_high2lowgid(inode->i_gid)); | |
2772 | raw_inode->i_uid_high = 0; | |
2773 | raw_inode->i_gid_high = 0; | |
2774 | } | |
2775 | raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); | |
2776 | raw_inode->i_size = cpu_to_le32(ei->i_disksize); | |
2777 | raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec); | |
2778 | raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); | |
2779 | raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); | |
2780 | raw_inode->i_blocks = cpu_to_le32(inode->i_blocks); | |
2781 | raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); | |
2782 | raw_inode->i_flags = cpu_to_le32(ei->i_flags); | |
2783 | #ifdef EXT3_FRAGMENTS | |
2784 | raw_inode->i_faddr = cpu_to_le32(ei->i_faddr); | |
2785 | raw_inode->i_frag = ei->i_frag_no; | |
2786 | raw_inode->i_fsize = ei->i_frag_size; | |
2787 | #endif | |
2788 | raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl); | |
2789 | if (!S_ISREG(inode->i_mode)) { | |
2790 | raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl); | |
2791 | } else { | |
2792 | raw_inode->i_size_high = | |
2793 | cpu_to_le32(ei->i_disksize >> 32); | |
2794 | if (ei->i_disksize > 0x7fffffffULL) { | |
2795 | struct super_block *sb = inode->i_sb; | |
2796 | if (!EXT3_HAS_RO_COMPAT_FEATURE(sb, | |
2797 | EXT3_FEATURE_RO_COMPAT_LARGE_FILE) || | |
2798 | EXT3_SB(sb)->s_es->s_rev_level == | |
2799 | cpu_to_le32(EXT3_GOOD_OLD_REV)) { | |
2800 | /* If this is the first large file | |
2801 | * created, add a flag to the superblock. | |
2802 | */ | |
2803 | err = ext3_journal_get_write_access(handle, | |
2804 | EXT3_SB(sb)->s_sbh); | |
2805 | if (err) | |
2806 | goto out_brelse; | |
2807 | ext3_update_dynamic_rev(sb); | |
2808 | EXT3_SET_RO_COMPAT_FEATURE(sb, | |
2809 | EXT3_FEATURE_RO_COMPAT_LARGE_FILE); | |
2810 | sb->s_dirt = 1; | |
2811 | handle->h_sync = 1; | |
2812 | err = ext3_journal_dirty_metadata(handle, | |
2813 | EXT3_SB(sb)->s_sbh); | |
2814 | } | |
2815 | } | |
2816 | } | |
2817 | raw_inode->i_generation = cpu_to_le32(inode->i_generation); | |
2818 | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { | |
2819 | if (old_valid_dev(inode->i_rdev)) { | |
2820 | raw_inode->i_block[0] = | |
2821 | cpu_to_le32(old_encode_dev(inode->i_rdev)); | |
2822 | raw_inode->i_block[1] = 0; | |
2823 | } else { | |
2824 | raw_inode->i_block[0] = 0; | |
2825 | raw_inode->i_block[1] = | |
2826 | cpu_to_le32(new_encode_dev(inode->i_rdev)); | |
2827 | raw_inode->i_block[2] = 0; | |
2828 | } | |
2829 | } else for (block = 0; block < EXT3_N_BLOCKS; block++) | |
2830 | raw_inode->i_block[block] = ei->i_data[block]; | |
2831 | ||
ff87b37d | 2832 | if (ei->i_extra_isize) |
1da177e4 LT |
2833 | raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); |
2834 | ||
2835 | BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); | |
2836 | rc = ext3_journal_dirty_metadata(handle, bh); | |
2837 | if (!err) | |
2838 | err = rc; | |
2839 | ei->i_state &= ~EXT3_STATE_NEW; | |
2840 | ||
2841 | out_brelse: | |
2842 | brelse (bh); | |
2843 | ext3_std_error(inode->i_sb, err); | |
2844 | return err; | |
2845 | } | |
2846 | ||
2847 | /* | |
2848 | * ext3_write_inode() | |
2849 | * | |
2850 | * We are called from a few places: | |
2851 | * | |
2852 | * - Within generic_file_write() for O_SYNC files. | |
2853 | * Here, there will be no transaction running. We wait for any running | |
2854 | * trasnaction to commit. | |
2855 | * | |
2856 | * - Within sys_sync(), kupdate and such. | |
2857 | * We wait on commit, if tol to. | |
2858 | * | |
2859 | * - Within prune_icache() (PF_MEMALLOC == true) | |
2860 | * Here we simply return. We can't afford to block kswapd on the | |
2861 | * journal commit. | |
2862 | * | |
2863 | * In all cases it is actually safe for us to return without doing anything, | |
2864 | * because the inode has been copied into a raw inode buffer in | |
2865 | * ext3_mark_inode_dirty(). This is a correctness thing for O_SYNC and for | |
2866 | * knfsd. | |
2867 | * | |
2868 | * Note that we are absolutely dependent upon all inode dirtiers doing the | |
2869 | * right thing: they *must* call mark_inode_dirty() after dirtying info in | |
2870 | * which we are interested. | |
2871 | * | |
2872 | * It would be a bug for them to not do this. The code: | |
2873 | * | |
2874 | * mark_inode_dirty(inode) | |
2875 | * stuff(); | |
2876 | * inode->i_size = expr; | |
2877 | * | |
2878 | * is in error because a kswapd-driven write_inode() could occur while | |
2879 | * `stuff()' is running, and the new i_size will be lost. Plus the inode | |
2880 | * will no longer be on the superblock's dirty inode list. | |
2881 | */ | |
2882 | int ext3_write_inode(struct inode *inode, int wait) | |
2883 | { | |
2884 | if (current->flags & PF_MEMALLOC) | |
2885 | return 0; | |
2886 | ||
2887 | if (ext3_journal_current_handle()) { | |
2888 | jbd_debug(0, "called recursively, non-PF_MEMALLOC!\n"); | |
2889 | dump_stack(); | |
2890 | return -EIO; | |
2891 | } | |
2892 | ||
2893 | if (!wait) | |
2894 | return 0; | |
2895 | ||
2896 | return ext3_force_commit(inode->i_sb); | |
2897 | } | |
2898 | ||
2899 | /* | |
2900 | * ext3_setattr() | |
2901 | * | |
2902 | * Called from notify_change. | |
2903 | * | |
2904 | * We want to trap VFS attempts to truncate the file as soon as | |
2905 | * possible. In particular, we want to make sure that when the VFS | |
2906 | * shrinks i_size, we put the inode on the orphan list and modify | |
2907 | * i_disksize immediately, so that during the subsequent flushing of | |
2908 | * dirty pages and freeing of disk blocks, we can guarantee that any | |
2909 | * commit will leave the blocks being flushed in an unused state on | |
2910 | * disk. (On recovery, the inode will get truncated and the blocks will | |
2911 | * be freed, so we have a strong guarantee that no future commit will | |
ae6ddcc5 | 2912 | * leave these blocks visible to the user.) |
1da177e4 LT |
2913 | * |
2914 | * Called with inode->sem down. | |
2915 | */ | |
2916 | int ext3_setattr(struct dentry *dentry, struct iattr *attr) | |
2917 | { | |
2918 | struct inode *inode = dentry->d_inode; | |
2919 | int error, rc = 0; | |
2920 | const unsigned int ia_valid = attr->ia_valid; | |
2921 | ||
2922 | error = inode_change_ok(inode, attr); | |
2923 | if (error) | |
2924 | return error; | |
2925 | ||
2926 | if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || | |
2927 | (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) { | |
2928 | handle_t *handle; | |
2929 | ||
2930 | /* (user+group)*(old+new) structure, inode write (sb, | |
2931 | * inode block, ? - but truncate inode update has it) */ | |
1f54587b JK |
2932 | handle = ext3_journal_start(inode, 2*(EXT3_QUOTA_INIT_BLOCKS(inode->i_sb)+ |
2933 | EXT3_QUOTA_DEL_BLOCKS(inode->i_sb))+3); | |
1da177e4 LT |
2934 | if (IS_ERR(handle)) { |
2935 | error = PTR_ERR(handle); | |
2936 | goto err_out; | |
2937 | } | |
2938 | error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0; | |
2939 | if (error) { | |
2940 | ext3_journal_stop(handle); | |
2941 | return error; | |
2942 | } | |
2943 | /* Update corresponding info in inode so that everything is in | |
2944 | * one transaction */ | |
2945 | if (attr->ia_valid & ATTR_UID) | |
2946 | inode->i_uid = attr->ia_uid; | |
2947 | if (attr->ia_valid & ATTR_GID) | |
2948 | inode->i_gid = attr->ia_gid; | |
2949 | error = ext3_mark_inode_dirty(handle, inode); | |
2950 | ext3_journal_stop(handle); | |
2951 | } | |
2952 | ||
2953 | if (S_ISREG(inode->i_mode) && | |
2954 | attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { | |
2955 | handle_t *handle; | |
2956 | ||
2957 | handle = ext3_journal_start(inode, 3); | |
2958 | if (IS_ERR(handle)) { | |
2959 | error = PTR_ERR(handle); | |
2960 | goto err_out; | |
2961 | } | |
2962 | ||
2963 | error = ext3_orphan_add(handle, inode); | |
2964 | EXT3_I(inode)->i_disksize = attr->ia_size; | |
2965 | rc = ext3_mark_inode_dirty(handle, inode); | |
2966 | if (!error) | |
2967 | error = rc; | |
2968 | ext3_journal_stop(handle); | |
2969 | } | |
2970 | ||
2971 | rc = inode_setattr(inode, attr); | |
2972 | ||
2973 | /* If inode_setattr's call to ext3_truncate failed to get a | |
2974 | * transaction handle at all, we need to clean up the in-core | |
2975 | * orphan list manually. */ | |
2976 | if (inode->i_nlink) | |
2977 | ext3_orphan_del(NULL, inode); | |
2978 | ||
2979 | if (!rc && (ia_valid & ATTR_MODE)) | |
2980 | rc = ext3_acl_chmod(inode); | |
2981 | ||
2982 | err_out: | |
2983 | ext3_std_error(inode->i_sb, error); | |
2984 | if (!error) | |
2985 | error = rc; | |
2986 | return error; | |
2987 | } | |
2988 | ||
2989 | ||
2990 | /* | |
d6859bfc | 2991 | * How many blocks doth make a writepage()? |
1da177e4 LT |
2992 | * |
2993 | * With N blocks per page, it may be: | |
2994 | * N data blocks | |
2995 | * 2 indirect block | |
2996 | * 2 dindirect | |
2997 | * 1 tindirect | |
2998 | * N+5 bitmap blocks (from the above) | |
2999 | * N+5 group descriptor summary blocks | |
3000 | * 1 inode block | |
3001 | * 1 superblock. | |
3002 | * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files | |
3003 | * | |
3004 | * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS | |
3005 | * | |
3006 | * With ordered or writeback data it's the same, less the N data blocks. | |
3007 | * | |
3008 | * If the inode's direct blocks can hold an integral number of pages then a | |
3009 | * page cannot straddle two indirect blocks, and we can only touch one indirect | |
3010 | * and dindirect block, and the "5" above becomes "3". | |
3011 | * | |
3012 | * This still overestimates under most circumstances. If we were to pass the | |
3013 | * start and end offsets in here as well we could do block_to_path() on each | |
3014 | * block and work out the exact number of indirects which are touched. Pah. | |
3015 | */ | |
3016 | ||
3017 | static int ext3_writepage_trans_blocks(struct inode *inode) | |
3018 | { | |
3019 | int bpp = ext3_journal_blocks_per_page(inode); | |
3020 | int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3; | |
3021 | int ret; | |
3022 | ||
3023 | if (ext3_should_journal_data(inode)) | |
3024 | ret = 3 * (bpp + indirects) + 2; | |
3025 | else | |
3026 | ret = 2 * (bpp + indirects) + 2; | |
3027 | ||
3028 | #ifdef CONFIG_QUOTA | |
3029 | /* We know that structure was already allocated during DQUOT_INIT so | |
3030 | * we will be updating only the data blocks + inodes */ | |
1f54587b | 3031 | ret += 2*EXT3_QUOTA_TRANS_BLOCKS(inode->i_sb); |
1da177e4 LT |
3032 | #endif |
3033 | ||
3034 | return ret; | |
3035 | } | |
3036 | ||
3037 | /* | |
3038 | * The caller must have previously called ext3_reserve_inode_write(). | |
3039 | * Give this, we know that the caller already has write access to iloc->bh. | |
3040 | */ | |
3041 | int ext3_mark_iloc_dirty(handle_t *handle, | |
3042 | struct inode *inode, struct ext3_iloc *iloc) | |
3043 | { | |
3044 | int err = 0; | |
3045 | ||
3046 | /* the do_update_inode consumes one bh->b_count */ | |
3047 | get_bh(iloc->bh); | |
3048 | ||
3049 | /* ext3_do_update_inode() does journal_dirty_metadata */ | |
3050 | err = ext3_do_update_inode(handle, inode, iloc); | |
3051 | put_bh(iloc->bh); | |
3052 | return err; | |
3053 | } | |
3054 | ||
ae6ddcc5 | 3055 | /* |
1da177e4 | 3056 | * On success, We end up with an outstanding reference count against |
ae6ddcc5 | 3057 | * iloc->bh. This _must_ be cleaned up later. |
1da177e4 LT |
3058 | */ |
3059 | ||
3060 | int | |
ae6ddcc5 | 3061 | ext3_reserve_inode_write(handle_t *handle, struct inode *inode, |
1da177e4 LT |
3062 | struct ext3_iloc *iloc) |
3063 | { | |
3064 | int err = 0; | |
3065 | if (handle) { | |
3066 | err = ext3_get_inode_loc(inode, iloc); | |
3067 | if (!err) { | |
3068 | BUFFER_TRACE(iloc->bh, "get_write_access"); | |
3069 | err = ext3_journal_get_write_access(handle, iloc->bh); | |
3070 | if (err) { | |
3071 | brelse(iloc->bh); | |
3072 | iloc->bh = NULL; | |
3073 | } | |
3074 | } | |
3075 | } | |
3076 | ext3_std_error(inode->i_sb, err); | |
3077 | return err; | |
3078 | } | |
3079 | ||
3080 | /* | |
d6859bfc AM |
3081 | * What we do here is to mark the in-core inode as clean with respect to inode |
3082 | * dirtiness (it may still be data-dirty). | |
1da177e4 LT |
3083 | * This means that the in-core inode may be reaped by prune_icache |
3084 | * without having to perform any I/O. This is a very good thing, | |
3085 | * because *any* task may call prune_icache - even ones which | |
3086 | * have a transaction open against a different journal. | |
3087 | * | |
3088 | * Is this cheating? Not really. Sure, we haven't written the | |
3089 | * inode out, but prune_icache isn't a user-visible syncing function. | |
3090 | * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) | |
3091 | * we start and wait on commits. | |
3092 | * | |
3093 | * Is this efficient/effective? Well, we're being nice to the system | |
3094 | * by cleaning up our inodes proactively so they can be reaped | |
3095 | * without I/O. But we are potentially leaving up to five seconds' | |
3096 | * worth of inodes floating about which prune_icache wants us to | |
3097 | * write out. One way to fix that would be to get prune_icache() | |
3098 | * to do a write_super() to free up some memory. It has the desired | |
3099 | * effect. | |
3100 | */ | |
3101 | int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode) | |
3102 | { | |
3103 | struct ext3_iloc iloc; | |
3104 | int err; | |
3105 | ||
3106 | might_sleep(); | |
3107 | err = ext3_reserve_inode_write(handle, inode, &iloc); | |
3108 | if (!err) | |
3109 | err = ext3_mark_iloc_dirty(handle, inode, &iloc); | |
3110 | return err; | |
3111 | } | |
3112 | ||
3113 | /* | |
d6859bfc | 3114 | * ext3_dirty_inode() is called from __mark_inode_dirty() |
1da177e4 LT |
3115 | * |
3116 | * We're really interested in the case where a file is being extended. | |
3117 | * i_size has been changed by generic_commit_write() and we thus need | |
3118 | * to include the updated inode in the current transaction. | |
3119 | * | |
3120 | * Also, DQUOT_ALLOC_SPACE() will always dirty the inode when blocks | |
3121 | * are allocated to the file. | |
3122 | * | |
3123 | * If the inode is marked synchronous, we don't honour that here - doing | |
3124 | * so would cause a commit on atime updates, which we don't bother doing. | |
3125 | * We handle synchronous inodes at the highest possible level. | |
3126 | */ | |
3127 | void ext3_dirty_inode(struct inode *inode) | |
3128 | { | |
3129 | handle_t *current_handle = ext3_journal_current_handle(); | |
3130 | handle_t *handle; | |
3131 | ||
3132 | handle = ext3_journal_start(inode, 2); | |
3133 | if (IS_ERR(handle)) | |
3134 | goto out; | |
3135 | if (current_handle && | |
3136 | current_handle->h_transaction != handle->h_transaction) { | |
3137 | /* This task has a transaction open against a different fs */ | |
3138 | printk(KERN_EMERG "%s: transactions do not match!\n", | |
3139 | __FUNCTION__); | |
3140 | } else { | |
3141 | jbd_debug(5, "marking dirty. outer handle=%p\n", | |
3142 | current_handle); | |
3143 | ext3_mark_inode_dirty(handle, inode); | |
3144 | } | |
3145 | ext3_journal_stop(handle); | |
3146 | out: | |
3147 | return; | |
3148 | } | |
3149 | ||
d6859bfc | 3150 | #if 0 |
ae6ddcc5 | 3151 | /* |
1da177e4 LT |
3152 | * Bind an inode's backing buffer_head into this transaction, to prevent |
3153 | * it from being flushed to disk early. Unlike | |
3154 | * ext3_reserve_inode_write, this leaves behind no bh reference and | |
3155 | * returns no iloc structure, so the caller needs to repeat the iloc | |
3156 | * lookup to mark the inode dirty later. | |
3157 | */ | |
d6859bfc | 3158 | static int ext3_pin_inode(handle_t *handle, struct inode *inode) |
1da177e4 LT |
3159 | { |
3160 | struct ext3_iloc iloc; | |
3161 | ||
3162 | int err = 0; | |
3163 | if (handle) { | |
3164 | err = ext3_get_inode_loc(inode, &iloc); | |
3165 | if (!err) { | |
3166 | BUFFER_TRACE(iloc.bh, "get_write_access"); | |
3167 | err = journal_get_write_access(handle, iloc.bh); | |
3168 | if (!err) | |
ae6ddcc5 | 3169 | err = ext3_journal_dirty_metadata(handle, |
1da177e4 LT |
3170 | iloc.bh); |
3171 | brelse(iloc.bh); | |
3172 | } | |
3173 | } | |
3174 | ext3_std_error(inode->i_sb, err); | |
3175 | return err; | |
3176 | } | |
3177 | #endif | |
3178 | ||
3179 | int ext3_change_inode_journal_flag(struct inode *inode, int val) | |
3180 | { | |
3181 | journal_t *journal; | |
3182 | handle_t *handle; | |
3183 | int err; | |
3184 | ||
3185 | /* | |
3186 | * We have to be very careful here: changing a data block's | |
3187 | * journaling status dynamically is dangerous. If we write a | |
3188 | * data block to the journal, change the status and then delete | |
3189 | * that block, we risk forgetting to revoke the old log record | |
3190 | * from the journal and so a subsequent replay can corrupt data. | |
3191 | * So, first we make sure that the journal is empty and that | |
3192 | * nobody is changing anything. | |
3193 | */ | |
3194 | ||
3195 | journal = EXT3_JOURNAL(inode); | |
3196 | if (is_journal_aborted(journal) || IS_RDONLY(inode)) | |
3197 | return -EROFS; | |
3198 | ||
3199 | journal_lock_updates(journal); | |
3200 | journal_flush(journal); | |
3201 | ||
3202 | /* | |
3203 | * OK, there are no updates running now, and all cached data is | |
3204 | * synced to disk. We are now in a completely consistent state | |
3205 | * which doesn't have anything in the journal, and we know that | |
3206 | * no filesystem updates are running, so it is safe to modify | |
3207 | * the inode's in-core data-journaling state flag now. | |
3208 | */ | |
3209 | ||
3210 | if (val) | |
3211 | EXT3_I(inode)->i_flags |= EXT3_JOURNAL_DATA_FL; | |
3212 | else | |
3213 | EXT3_I(inode)->i_flags &= ~EXT3_JOURNAL_DATA_FL; | |
3214 | ext3_set_aops(inode); | |
3215 | ||
3216 | journal_unlock_updates(journal); | |
3217 | ||
3218 | /* Finally we can mark the inode as dirty. */ | |
3219 | ||
3220 | handle = ext3_journal_start(inode, 1); | |
3221 | if (IS_ERR(handle)) | |
3222 | return PTR_ERR(handle); | |
3223 | ||
3224 | err = ext3_mark_inode_dirty(handle, inode); | |
3225 | handle->h_sync = 1; | |
3226 | ext3_journal_stop(handle); | |
3227 | ext3_std_error(inode->i_sb, err); | |
3228 | ||
3229 | return err; | |
3230 | } |