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1 | /* | |
2 | * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com | |
3 | * Written by Alex Tomas <alex@clusterfs.com> | |
4 | * | |
5 | * Architecture independence: | |
6 | * Copyright (c) 2005, Bull S.A. | |
7 | * Written by Pierre Peiffer <pierre.peiffer@bull.net> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License version 2 as | |
11 | * published by the Free Software Foundation. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public Licens | |
19 | * along with this program; if not, write to the Free Software | |
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- | |
21 | */ | |
22 | ||
23 | /* | |
24 | * Extents support for EXT4 | |
25 | * | |
26 | * TODO: | |
27 | * - ext4*_error() should be used in some situations | |
28 | * - analyze all BUG()/BUG_ON(), use -EIO where appropriate | |
29 | * - smart tree reduction | |
30 | */ | |
31 | ||
32 | #include <linux/module.h> | |
33 | #include <linux/fs.h> | |
34 | #include <linux/time.h> | |
35 | #include <linux/jbd2.h> | |
36 | #include <linux/highuid.h> | |
37 | #include <linux/pagemap.h> | |
38 | #include <linux/quotaops.h> | |
39 | #include <linux/string.h> | |
40 | #include <linux/slab.h> | |
41 | #include <linux/falloc.h> | |
42 | #include <asm/uaccess.h> | |
43 | #include <linux/fiemap.h> | |
44 | #include "ext4_jbd2.h" | |
45 | ||
46 | #include <trace/events/ext4.h> | |
47 | ||
48 | static int ext4_split_extent(handle_t *handle, | |
49 | struct inode *inode, | |
50 | struct ext4_ext_path *path, | |
51 | struct ext4_map_blocks *map, | |
52 | int split_flag, | |
53 | int flags); | |
54 | ||
55 | static int ext4_ext_truncate_extend_restart(handle_t *handle, | |
56 | struct inode *inode, | |
57 | int needed) | |
58 | { | |
59 | int err; | |
60 | ||
61 | if (!ext4_handle_valid(handle)) | |
62 | return 0; | |
63 | if (handle->h_buffer_credits > needed) | |
64 | return 0; | |
65 | err = ext4_journal_extend(handle, needed); | |
66 | if (err <= 0) | |
67 | return err; | |
68 | err = ext4_truncate_restart_trans(handle, inode, needed); | |
69 | if (err == 0) | |
70 | err = -EAGAIN; | |
71 | ||
72 | return err; | |
73 | } | |
74 | ||
75 | /* | |
76 | * could return: | |
77 | * - EROFS | |
78 | * - ENOMEM | |
79 | */ | |
80 | static int ext4_ext_get_access(handle_t *handle, struct inode *inode, | |
81 | struct ext4_ext_path *path) | |
82 | { | |
83 | if (path->p_bh) { | |
84 | /* path points to block */ | |
85 | return ext4_journal_get_write_access(handle, path->p_bh); | |
86 | } | |
87 | /* path points to leaf/index in inode body */ | |
88 | /* we use in-core data, no need to protect them */ | |
89 | return 0; | |
90 | } | |
91 | ||
92 | /* | |
93 | * could return: | |
94 | * - EROFS | |
95 | * - ENOMEM | |
96 | * - EIO | |
97 | */ | |
98 | #define ext4_ext_dirty(handle, inode, path) \ | |
99 | __ext4_ext_dirty(__func__, __LINE__, (handle), (inode), (path)) | |
100 | static int __ext4_ext_dirty(const char *where, unsigned int line, | |
101 | handle_t *handle, struct inode *inode, | |
102 | struct ext4_ext_path *path) | |
103 | { | |
104 | int err; | |
105 | if (path->p_bh) { | |
106 | /* path points to block */ | |
107 | err = __ext4_handle_dirty_metadata(where, line, handle, | |
108 | inode, path->p_bh); | |
109 | } else { | |
110 | /* path points to leaf/index in inode body */ | |
111 | err = ext4_mark_inode_dirty(handle, inode); | |
112 | } | |
113 | return err; | |
114 | } | |
115 | ||
116 | static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode, | |
117 | struct ext4_ext_path *path, | |
118 | ext4_lblk_t block) | |
119 | { | |
120 | int depth; | |
121 | ||
122 | if (path) { | |
123 | struct ext4_extent *ex; | |
124 | depth = path->p_depth; | |
125 | ||
126 | /* | |
127 | * Try to predict block placement assuming that we are | |
128 | * filling in a file which will eventually be | |
129 | * non-sparse --- i.e., in the case of libbfd writing | |
130 | * an ELF object sections out-of-order but in a way | |
131 | * the eventually results in a contiguous object or | |
132 | * executable file, or some database extending a table | |
133 | * space file. However, this is actually somewhat | |
134 | * non-ideal if we are writing a sparse file such as | |
135 | * qemu or KVM writing a raw image file that is going | |
136 | * to stay fairly sparse, since it will end up | |
137 | * fragmenting the file system's free space. Maybe we | |
138 | * should have some hueristics or some way to allow | |
139 | * userspace to pass a hint to file system, | |
140 | * especially if the latter case turns out to be | |
141 | * common. | |
142 | */ | |
143 | ex = path[depth].p_ext; | |
144 | if (ex) { | |
145 | ext4_fsblk_t ext_pblk = ext4_ext_pblock(ex); | |
146 | ext4_lblk_t ext_block = le32_to_cpu(ex->ee_block); | |
147 | ||
148 | if (block > ext_block) | |
149 | return ext_pblk + (block - ext_block); | |
150 | else | |
151 | return ext_pblk - (ext_block - block); | |
152 | } | |
153 | ||
154 | /* it looks like index is empty; | |
155 | * try to find starting block from index itself */ | |
156 | if (path[depth].p_bh) | |
157 | return path[depth].p_bh->b_blocknr; | |
158 | } | |
159 | ||
160 | /* OK. use inode's group */ | |
161 | return ext4_inode_to_goal_block(inode); | |
162 | } | |
163 | ||
164 | /* | |
165 | * Allocation for a meta data block | |
166 | */ | |
167 | static ext4_fsblk_t | |
168 | ext4_ext_new_meta_block(handle_t *handle, struct inode *inode, | |
169 | struct ext4_ext_path *path, | |
170 | struct ext4_extent *ex, int *err, unsigned int flags) | |
171 | { | |
172 | ext4_fsblk_t goal, newblock; | |
173 | ||
174 | goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block)); | |
175 | newblock = ext4_new_meta_blocks(handle, inode, goal, flags, | |
176 | NULL, err); | |
177 | return newblock; | |
178 | } | |
179 | ||
180 | static inline int ext4_ext_space_block(struct inode *inode, int check) | |
181 | { | |
182 | int size; | |
183 | ||
184 | size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header)) | |
185 | / sizeof(struct ext4_extent); | |
186 | if (!check) { | |
187 | #ifdef AGGRESSIVE_TEST | |
188 | if (size > 6) | |
189 | size = 6; | |
190 | #endif | |
191 | } | |
192 | return size; | |
193 | } | |
194 | ||
195 | static inline int ext4_ext_space_block_idx(struct inode *inode, int check) | |
196 | { | |
197 | int size; | |
198 | ||
199 | size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header)) | |
200 | / sizeof(struct ext4_extent_idx); | |
201 | if (!check) { | |
202 | #ifdef AGGRESSIVE_TEST | |
203 | if (size > 5) | |
204 | size = 5; | |
205 | #endif | |
206 | } | |
207 | return size; | |
208 | } | |
209 | ||
210 | static inline int ext4_ext_space_root(struct inode *inode, int check) | |
211 | { | |
212 | int size; | |
213 | ||
214 | size = sizeof(EXT4_I(inode)->i_data); | |
215 | size -= sizeof(struct ext4_extent_header); | |
216 | size /= sizeof(struct ext4_extent); | |
217 | if (!check) { | |
218 | #ifdef AGGRESSIVE_TEST | |
219 | if (size > 3) | |
220 | size = 3; | |
221 | #endif | |
222 | } | |
223 | return size; | |
224 | } | |
225 | ||
226 | static inline int ext4_ext_space_root_idx(struct inode *inode, int check) | |
227 | { | |
228 | int size; | |
229 | ||
230 | size = sizeof(EXT4_I(inode)->i_data); | |
231 | size -= sizeof(struct ext4_extent_header); | |
232 | size /= sizeof(struct ext4_extent_idx); | |
233 | if (!check) { | |
234 | #ifdef AGGRESSIVE_TEST | |
235 | if (size > 4) | |
236 | size = 4; | |
237 | #endif | |
238 | } | |
239 | return size; | |
240 | } | |
241 | ||
242 | /* | |
243 | * Calculate the number of metadata blocks needed | |
244 | * to allocate @blocks | |
245 | * Worse case is one block per extent | |
246 | */ | |
247 | int ext4_ext_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock) | |
248 | { | |
249 | struct ext4_inode_info *ei = EXT4_I(inode); | |
250 | int idxs, num = 0; | |
251 | ||
252 | idxs = ((inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header)) | |
253 | / sizeof(struct ext4_extent_idx)); | |
254 | ||
255 | /* | |
256 | * If the new delayed allocation block is contiguous with the | |
257 | * previous da block, it can share index blocks with the | |
258 | * previous block, so we only need to allocate a new index | |
259 | * block every idxs leaf blocks. At ldxs**2 blocks, we need | |
260 | * an additional index block, and at ldxs**3 blocks, yet | |
261 | * another index blocks. | |
262 | */ | |
263 | if (ei->i_da_metadata_calc_len && | |
264 | ei->i_da_metadata_calc_last_lblock+1 == lblock) { | |
265 | if ((ei->i_da_metadata_calc_len % idxs) == 0) | |
266 | num++; | |
267 | if ((ei->i_da_metadata_calc_len % (idxs*idxs)) == 0) | |
268 | num++; | |
269 | if ((ei->i_da_metadata_calc_len % (idxs*idxs*idxs)) == 0) { | |
270 | num++; | |
271 | ei->i_da_metadata_calc_len = 0; | |
272 | } else | |
273 | ei->i_da_metadata_calc_len++; | |
274 | ei->i_da_metadata_calc_last_lblock++; | |
275 | return num; | |
276 | } | |
277 | ||
278 | /* | |
279 | * In the worst case we need a new set of index blocks at | |
280 | * every level of the inode's extent tree. | |
281 | */ | |
282 | ei->i_da_metadata_calc_len = 1; | |
283 | ei->i_da_metadata_calc_last_lblock = lblock; | |
284 | return ext_depth(inode) + 1; | |
285 | } | |
286 | ||
287 | static int | |
288 | ext4_ext_max_entries(struct inode *inode, int depth) | |
289 | { | |
290 | int max; | |
291 | ||
292 | if (depth == ext_depth(inode)) { | |
293 | if (depth == 0) | |
294 | max = ext4_ext_space_root(inode, 1); | |
295 | else | |
296 | max = ext4_ext_space_root_idx(inode, 1); | |
297 | } else { | |
298 | if (depth == 0) | |
299 | max = ext4_ext_space_block(inode, 1); | |
300 | else | |
301 | max = ext4_ext_space_block_idx(inode, 1); | |
302 | } | |
303 | ||
304 | return max; | |
305 | } | |
306 | ||
307 | static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext) | |
308 | { | |
309 | ext4_fsblk_t block = ext4_ext_pblock(ext); | |
310 | int len = ext4_ext_get_actual_len(ext); | |
311 | ||
312 | return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len); | |
313 | } | |
314 | ||
315 | static int ext4_valid_extent_idx(struct inode *inode, | |
316 | struct ext4_extent_idx *ext_idx) | |
317 | { | |
318 | ext4_fsblk_t block = ext4_idx_pblock(ext_idx); | |
319 | ||
320 | return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, 1); | |
321 | } | |
322 | ||
323 | static int ext4_valid_extent_entries(struct inode *inode, | |
324 | struct ext4_extent_header *eh, | |
325 | int depth) | |
326 | { | |
327 | struct ext4_extent *ext; | |
328 | struct ext4_extent_idx *ext_idx; | |
329 | unsigned short entries; | |
330 | if (eh->eh_entries == 0) | |
331 | return 1; | |
332 | ||
333 | entries = le16_to_cpu(eh->eh_entries); | |
334 | ||
335 | if (depth == 0) { | |
336 | /* leaf entries */ | |
337 | ext = EXT_FIRST_EXTENT(eh); | |
338 | while (entries) { | |
339 | if (!ext4_valid_extent(inode, ext)) | |
340 | return 0; | |
341 | ext++; | |
342 | entries--; | |
343 | } | |
344 | } else { | |
345 | ext_idx = EXT_FIRST_INDEX(eh); | |
346 | while (entries) { | |
347 | if (!ext4_valid_extent_idx(inode, ext_idx)) | |
348 | return 0; | |
349 | ext_idx++; | |
350 | entries--; | |
351 | } | |
352 | } | |
353 | return 1; | |
354 | } | |
355 | ||
356 | static int __ext4_ext_check(const char *function, unsigned int line, | |
357 | struct inode *inode, struct ext4_extent_header *eh, | |
358 | int depth) | |
359 | { | |
360 | const char *error_msg; | |
361 | int max = 0; | |
362 | ||
363 | if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) { | |
364 | error_msg = "invalid magic"; | |
365 | goto corrupted; | |
366 | } | |
367 | if (unlikely(le16_to_cpu(eh->eh_depth) != depth)) { | |
368 | error_msg = "unexpected eh_depth"; | |
369 | goto corrupted; | |
370 | } | |
371 | if (unlikely(eh->eh_max == 0)) { | |
372 | error_msg = "invalid eh_max"; | |
373 | goto corrupted; | |
374 | } | |
375 | max = ext4_ext_max_entries(inode, depth); | |
376 | if (unlikely(le16_to_cpu(eh->eh_max) > max)) { | |
377 | error_msg = "too large eh_max"; | |
378 | goto corrupted; | |
379 | } | |
380 | if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) { | |
381 | error_msg = "invalid eh_entries"; | |
382 | goto corrupted; | |
383 | } | |
384 | if (!ext4_valid_extent_entries(inode, eh, depth)) { | |
385 | error_msg = "invalid extent entries"; | |
386 | goto corrupted; | |
387 | } | |
388 | return 0; | |
389 | ||
390 | corrupted: | |
391 | ext4_error_inode(inode, function, line, 0, | |
392 | "bad header/extent: %s - magic %x, " | |
393 | "entries %u, max %u(%u), depth %u(%u)", | |
394 | error_msg, le16_to_cpu(eh->eh_magic), | |
395 | le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max), | |
396 | max, le16_to_cpu(eh->eh_depth), depth); | |
397 | ||
398 | return -EIO; | |
399 | } | |
400 | ||
401 | #define ext4_ext_check(inode, eh, depth) \ | |
402 | __ext4_ext_check(__func__, __LINE__, inode, eh, depth) | |
403 | ||
404 | int ext4_ext_check_inode(struct inode *inode) | |
405 | { | |
406 | return ext4_ext_check(inode, ext_inode_hdr(inode), ext_depth(inode)); | |
407 | } | |
408 | ||
409 | #ifdef EXT_DEBUG | |
410 | static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path) | |
411 | { | |
412 | int k, l = path->p_depth; | |
413 | ||
414 | ext_debug("path:"); | |
415 | for (k = 0; k <= l; k++, path++) { | |
416 | if (path->p_idx) { | |
417 | ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block), | |
418 | ext4_idx_pblock(path->p_idx)); | |
419 | } else if (path->p_ext) { | |
420 | ext_debug(" %d:[%d]%d:%llu ", | |
421 | le32_to_cpu(path->p_ext->ee_block), | |
422 | ext4_ext_is_uninitialized(path->p_ext), | |
423 | ext4_ext_get_actual_len(path->p_ext), | |
424 | ext4_ext_pblock(path->p_ext)); | |
425 | } else | |
426 | ext_debug(" []"); | |
427 | } | |
428 | ext_debug("\n"); | |
429 | } | |
430 | ||
431 | static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path) | |
432 | { | |
433 | int depth = ext_depth(inode); | |
434 | struct ext4_extent_header *eh; | |
435 | struct ext4_extent *ex; | |
436 | int i; | |
437 | ||
438 | if (!path) | |
439 | return; | |
440 | ||
441 | eh = path[depth].p_hdr; | |
442 | ex = EXT_FIRST_EXTENT(eh); | |
443 | ||
444 | ext_debug("Displaying leaf extents for inode %lu\n", inode->i_ino); | |
445 | ||
446 | for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) { | |
447 | ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block), | |
448 | ext4_ext_is_uninitialized(ex), | |
449 | ext4_ext_get_actual_len(ex), ext4_ext_pblock(ex)); | |
450 | } | |
451 | ext_debug("\n"); | |
452 | } | |
453 | ||
454 | static void ext4_ext_show_move(struct inode *inode, struct ext4_ext_path *path, | |
455 | ext4_fsblk_t newblock, int level) | |
456 | { | |
457 | int depth = ext_depth(inode); | |
458 | struct ext4_extent *ex; | |
459 | ||
460 | if (depth != level) { | |
461 | struct ext4_extent_idx *idx; | |
462 | idx = path[level].p_idx; | |
463 | while (idx <= EXT_MAX_INDEX(path[level].p_hdr)) { | |
464 | ext_debug("%d: move %d:%llu in new index %llu\n", level, | |
465 | le32_to_cpu(idx->ei_block), | |
466 | ext4_idx_pblock(idx), | |
467 | newblock); | |
468 | idx++; | |
469 | } | |
470 | ||
471 | return; | |
472 | } | |
473 | ||
474 | ex = path[depth].p_ext; | |
475 | while (ex <= EXT_MAX_EXTENT(path[depth].p_hdr)) { | |
476 | ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n", | |
477 | le32_to_cpu(ex->ee_block), | |
478 | ext4_ext_pblock(ex), | |
479 | ext4_ext_is_uninitialized(ex), | |
480 | ext4_ext_get_actual_len(ex), | |
481 | newblock); | |
482 | ex++; | |
483 | } | |
484 | } | |
485 | ||
486 | #else | |
487 | #define ext4_ext_show_path(inode, path) | |
488 | #define ext4_ext_show_leaf(inode, path) | |
489 | #define ext4_ext_show_move(inode, path, newblock, level) | |
490 | #endif | |
491 | ||
492 | void ext4_ext_drop_refs(struct ext4_ext_path *path) | |
493 | { | |
494 | int depth = path->p_depth; | |
495 | int i; | |
496 | ||
497 | for (i = 0; i <= depth; i++, path++) | |
498 | if (path->p_bh) { | |
499 | brelse(path->p_bh); | |
500 | path->p_bh = NULL; | |
501 | } | |
502 | } | |
503 | ||
504 | /* | |
505 | * ext4_ext_binsearch_idx: | |
506 | * binary search for the closest index of the given block | |
507 | * the header must be checked before calling this | |
508 | */ | |
509 | static void | |
510 | ext4_ext_binsearch_idx(struct inode *inode, | |
511 | struct ext4_ext_path *path, ext4_lblk_t block) | |
512 | { | |
513 | struct ext4_extent_header *eh = path->p_hdr; | |
514 | struct ext4_extent_idx *r, *l, *m; | |
515 | ||
516 | ||
517 | ext_debug("binsearch for %u(idx): ", block); | |
518 | ||
519 | l = EXT_FIRST_INDEX(eh) + 1; | |
520 | r = EXT_LAST_INDEX(eh); | |
521 | while (l <= r) { | |
522 | m = l + (r - l) / 2; | |
523 | if (block < le32_to_cpu(m->ei_block)) | |
524 | r = m - 1; | |
525 | else | |
526 | l = m + 1; | |
527 | ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block), | |
528 | m, le32_to_cpu(m->ei_block), | |
529 | r, le32_to_cpu(r->ei_block)); | |
530 | } | |
531 | ||
532 | path->p_idx = l - 1; | |
533 | ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block), | |
534 | ext4_idx_pblock(path->p_idx)); | |
535 | ||
536 | #ifdef CHECK_BINSEARCH | |
537 | { | |
538 | struct ext4_extent_idx *chix, *ix; | |
539 | int k; | |
540 | ||
541 | chix = ix = EXT_FIRST_INDEX(eh); | |
542 | for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) { | |
543 | if (k != 0 && | |
544 | le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) { | |
545 | printk(KERN_DEBUG "k=%d, ix=0x%p, " | |
546 | "first=0x%p\n", k, | |
547 | ix, EXT_FIRST_INDEX(eh)); | |
548 | printk(KERN_DEBUG "%u <= %u\n", | |
549 | le32_to_cpu(ix->ei_block), | |
550 | le32_to_cpu(ix[-1].ei_block)); | |
551 | } | |
552 | BUG_ON(k && le32_to_cpu(ix->ei_block) | |
553 | <= le32_to_cpu(ix[-1].ei_block)); | |
554 | if (block < le32_to_cpu(ix->ei_block)) | |
555 | break; | |
556 | chix = ix; | |
557 | } | |
558 | BUG_ON(chix != path->p_idx); | |
559 | } | |
560 | #endif | |
561 | ||
562 | } | |
563 | ||
564 | /* | |
565 | * ext4_ext_binsearch: | |
566 | * binary search for closest extent of the given block | |
567 | * the header must be checked before calling this | |
568 | */ | |
569 | static void | |
570 | ext4_ext_binsearch(struct inode *inode, | |
571 | struct ext4_ext_path *path, ext4_lblk_t block) | |
572 | { | |
573 | struct ext4_extent_header *eh = path->p_hdr; | |
574 | struct ext4_extent *r, *l, *m; | |
575 | ||
576 | if (eh->eh_entries == 0) { | |
577 | /* | |
578 | * this leaf is empty: | |
579 | * we get such a leaf in split/add case | |
580 | */ | |
581 | return; | |
582 | } | |
583 | ||
584 | ext_debug("binsearch for %u: ", block); | |
585 | ||
586 | l = EXT_FIRST_EXTENT(eh) + 1; | |
587 | r = EXT_LAST_EXTENT(eh); | |
588 | ||
589 | while (l <= r) { | |
590 | m = l + (r - l) / 2; | |
591 | if (block < le32_to_cpu(m->ee_block)) | |
592 | r = m - 1; | |
593 | else | |
594 | l = m + 1; | |
595 | ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block), | |
596 | m, le32_to_cpu(m->ee_block), | |
597 | r, le32_to_cpu(r->ee_block)); | |
598 | } | |
599 | ||
600 | path->p_ext = l - 1; | |
601 | ext_debug(" -> %d:%llu:[%d]%d ", | |
602 | le32_to_cpu(path->p_ext->ee_block), | |
603 | ext4_ext_pblock(path->p_ext), | |
604 | ext4_ext_is_uninitialized(path->p_ext), | |
605 | ext4_ext_get_actual_len(path->p_ext)); | |
606 | ||
607 | #ifdef CHECK_BINSEARCH | |
608 | { | |
609 | struct ext4_extent *chex, *ex; | |
610 | int k; | |
611 | ||
612 | chex = ex = EXT_FIRST_EXTENT(eh); | |
613 | for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) { | |
614 | BUG_ON(k && le32_to_cpu(ex->ee_block) | |
615 | <= le32_to_cpu(ex[-1].ee_block)); | |
616 | if (block < le32_to_cpu(ex->ee_block)) | |
617 | break; | |
618 | chex = ex; | |
619 | } | |
620 | BUG_ON(chex != path->p_ext); | |
621 | } | |
622 | #endif | |
623 | ||
624 | } | |
625 | ||
626 | int ext4_ext_tree_init(handle_t *handle, struct inode *inode) | |
627 | { | |
628 | struct ext4_extent_header *eh; | |
629 | ||
630 | eh = ext_inode_hdr(inode); | |
631 | eh->eh_depth = 0; | |
632 | eh->eh_entries = 0; | |
633 | eh->eh_magic = EXT4_EXT_MAGIC; | |
634 | eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode, 0)); | |
635 | ext4_mark_inode_dirty(handle, inode); | |
636 | ext4_ext_invalidate_cache(inode); | |
637 | return 0; | |
638 | } | |
639 | ||
640 | struct ext4_ext_path * | |
641 | ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block, | |
642 | struct ext4_ext_path *path) | |
643 | { | |
644 | struct ext4_extent_header *eh; | |
645 | struct buffer_head *bh; | |
646 | short int depth, i, ppos = 0, alloc = 0; | |
647 | ||
648 | eh = ext_inode_hdr(inode); | |
649 | depth = ext_depth(inode); | |
650 | ||
651 | /* account possible depth increase */ | |
652 | if (!path) { | |
653 | path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 2), | |
654 | GFP_NOFS); | |
655 | if (!path) | |
656 | return ERR_PTR(-ENOMEM); | |
657 | alloc = 1; | |
658 | } | |
659 | path[0].p_hdr = eh; | |
660 | path[0].p_bh = NULL; | |
661 | ||
662 | i = depth; | |
663 | /* walk through the tree */ | |
664 | while (i) { | |
665 | int need_to_validate = 0; | |
666 | ||
667 | ext_debug("depth %d: num %d, max %d\n", | |
668 | ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max)); | |
669 | ||
670 | ext4_ext_binsearch_idx(inode, path + ppos, block); | |
671 | path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx); | |
672 | path[ppos].p_depth = i; | |
673 | path[ppos].p_ext = NULL; | |
674 | ||
675 | bh = sb_getblk(inode->i_sb, path[ppos].p_block); | |
676 | if (unlikely(!bh)) | |
677 | goto err; | |
678 | if (!bh_uptodate_or_lock(bh)) { | |
679 | trace_ext4_ext_load_extent(inode, block, | |
680 | path[ppos].p_block); | |
681 | if (bh_submit_read(bh) < 0) { | |
682 | put_bh(bh); | |
683 | goto err; | |
684 | } | |
685 | /* validate the extent entries */ | |
686 | need_to_validate = 1; | |
687 | } | |
688 | eh = ext_block_hdr(bh); | |
689 | ppos++; | |
690 | if (unlikely(ppos > depth)) { | |
691 | put_bh(bh); | |
692 | EXT4_ERROR_INODE(inode, | |
693 | "ppos %d > depth %d", ppos, depth); | |
694 | goto err; | |
695 | } | |
696 | path[ppos].p_bh = bh; | |
697 | path[ppos].p_hdr = eh; | |
698 | i--; | |
699 | ||
700 | if (need_to_validate && ext4_ext_check(inode, eh, i)) | |
701 | goto err; | |
702 | } | |
703 | ||
704 | path[ppos].p_depth = i; | |
705 | path[ppos].p_ext = NULL; | |
706 | path[ppos].p_idx = NULL; | |
707 | ||
708 | /* find extent */ | |
709 | ext4_ext_binsearch(inode, path + ppos, block); | |
710 | /* if not an empty leaf */ | |
711 | if (path[ppos].p_ext) | |
712 | path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext); | |
713 | ||
714 | ext4_ext_show_path(inode, path); | |
715 | ||
716 | return path; | |
717 | ||
718 | err: | |
719 | ext4_ext_drop_refs(path); | |
720 | if (alloc) | |
721 | kfree(path); | |
722 | return ERR_PTR(-EIO); | |
723 | } | |
724 | ||
725 | /* | |
726 | * ext4_ext_insert_index: | |
727 | * insert new index [@logical;@ptr] into the block at @curp; | |
728 | * check where to insert: before @curp or after @curp | |
729 | */ | |
730 | static int ext4_ext_insert_index(handle_t *handle, struct inode *inode, | |
731 | struct ext4_ext_path *curp, | |
732 | int logical, ext4_fsblk_t ptr) | |
733 | { | |
734 | struct ext4_extent_idx *ix; | |
735 | int len, err; | |
736 | ||
737 | err = ext4_ext_get_access(handle, inode, curp); | |
738 | if (err) | |
739 | return err; | |
740 | ||
741 | if (unlikely(logical == le32_to_cpu(curp->p_idx->ei_block))) { | |
742 | EXT4_ERROR_INODE(inode, | |
743 | "logical %d == ei_block %d!", | |
744 | logical, le32_to_cpu(curp->p_idx->ei_block)); | |
745 | return -EIO; | |
746 | } | |
747 | ||
748 | if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries) | |
749 | >= le16_to_cpu(curp->p_hdr->eh_max))) { | |
750 | EXT4_ERROR_INODE(inode, | |
751 | "eh_entries %d >= eh_max %d!", | |
752 | le16_to_cpu(curp->p_hdr->eh_entries), | |
753 | le16_to_cpu(curp->p_hdr->eh_max)); | |
754 | return -EIO; | |
755 | } | |
756 | ||
757 | len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx; | |
758 | if (logical > le32_to_cpu(curp->p_idx->ei_block)) { | |
759 | /* insert after */ | |
760 | if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) { | |
761 | len = (len - 1) * sizeof(struct ext4_extent_idx); | |
762 | len = len < 0 ? 0 : len; | |
763 | ext_debug("insert new index %d after: %llu. " | |
764 | "move %d from 0x%p to 0x%p\n", | |
765 | logical, ptr, len, | |
766 | (curp->p_idx + 1), (curp->p_idx + 2)); | |
767 | memmove(curp->p_idx + 2, curp->p_idx + 1, len); | |
768 | } | |
769 | ix = curp->p_idx + 1; | |
770 | } else { | |
771 | /* insert before */ | |
772 | len = len * sizeof(struct ext4_extent_idx); | |
773 | len = len < 0 ? 0 : len; | |
774 | ext_debug("insert new index %d before: %llu. " | |
775 | "move %d from 0x%p to 0x%p\n", | |
776 | logical, ptr, len, | |
777 | curp->p_idx, (curp->p_idx + 1)); | |
778 | memmove(curp->p_idx + 1, curp->p_idx, len); | |
779 | ix = curp->p_idx; | |
780 | } | |
781 | ||
782 | if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) { | |
783 | EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!"); | |
784 | return -EIO; | |
785 | } | |
786 | ||
787 | ix->ei_block = cpu_to_le32(logical); | |
788 | ext4_idx_store_pblock(ix, ptr); | |
789 | le16_add_cpu(&curp->p_hdr->eh_entries, 1); | |
790 | ||
791 | if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) { | |
792 | EXT4_ERROR_INODE(inode, "ix > EXT_LAST_INDEX!"); | |
793 | return -EIO; | |
794 | } | |
795 | ||
796 | err = ext4_ext_dirty(handle, inode, curp); | |
797 | ext4_std_error(inode->i_sb, err); | |
798 | ||
799 | return err; | |
800 | } | |
801 | ||
802 | /* | |
803 | * ext4_ext_split: | |
804 | * inserts new subtree into the path, using free index entry | |
805 | * at depth @at: | |
806 | * - allocates all needed blocks (new leaf and all intermediate index blocks) | |
807 | * - makes decision where to split | |
808 | * - moves remaining extents and index entries (right to the split point) | |
809 | * into the newly allocated blocks | |
810 | * - initializes subtree | |
811 | */ | |
812 | static int ext4_ext_split(handle_t *handle, struct inode *inode, | |
813 | unsigned int flags, | |
814 | struct ext4_ext_path *path, | |
815 | struct ext4_extent *newext, int at) | |
816 | { | |
817 | struct buffer_head *bh = NULL; | |
818 | int depth = ext_depth(inode); | |
819 | struct ext4_extent_header *neh; | |
820 | struct ext4_extent_idx *fidx; | |
821 | int i = at, k, m, a; | |
822 | ext4_fsblk_t newblock, oldblock; | |
823 | __le32 border; | |
824 | ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */ | |
825 | int err = 0; | |
826 | ||
827 | /* make decision: where to split? */ | |
828 | /* FIXME: now decision is simplest: at current extent */ | |
829 | ||
830 | /* if current leaf will be split, then we should use | |
831 | * border from split point */ | |
832 | if (unlikely(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr))) { | |
833 | EXT4_ERROR_INODE(inode, "p_ext > EXT_MAX_EXTENT!"); | |
834 | return -EIO; | |
835 | } | |
836 | if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) { | |
837 | border = path[depth].p_ext[1].ee_block; | |
838 | ext_debug("leaf will be split." | |
839 | " next leaf starts at %d\n", | |
840 | le32_to_cpu(border)); | |
841 | } else { | |
842 | border = newext->ee_block; | |
843 | ext_debug("leaf will be added." | |
844 | " next leaf starts at %d\n", | |
845 | le32_to_cpu(border)); | |
846 | } | |
847 | ||
848 | /* | |
849 | * If error occurs, then we break processing | |
850 | * and mark filesystem read-only. index won't | |
851 | * be inserted and tree will be in consistent | |
852 | * state. Next mount will repair buffers too. | |
853 | */ | |
854 | ||
855 | /* | |
856 | * Get array to track all allocated blocks. | |
857 | * We need this to handle errors and free blocks | |
858 | * upon them. | |
859 | */ | |
860 | ablocks = kzalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS); | |
861 | if (!ablocks) | |
862 | return -ENOMEM; | |
863 | ||
864 | /* allocate all needed blocks */ | |
865 | ext_debug("allocate %d blocks for indexes/leaf\n", depth - at); | |
866 | for (a = 0; a < depth - at; a++) { | |
867 | newblock = ext4_ext_new_meta_block(handle, inode, path, | |
868 | newext, &err, flags); | |
869 | if (newblock == 0) | |
870 | goto cleanup; | |
871 | ablocks[a] = newblock; | |
872 | } | |
873 | ||
874 | /* initialize new leaf */ | |
875 | newblock = ablocks[--a]; | |
876 | if (unlikely(newblock == 0)) { | |
877 | EXT4_ERROR_INODE(inode, "newblock == 0!"); | |
878 | err = -EIO; | |
879 | goto cleanup; | |
880 | } | |
881 | bh = sb_getblk(inode->i_sb, newblock); | |
882 | if (!bh) { | |
883 | err = -EIO; | |
884 | goto cleanup; | |
885 | } | |
886 | lock_buffer(bh); | |
887 | ||
888 | err = ext4_journal_get_create_access(handle, bh); | |
889 | if (err) | |
890 | goto cleanup; | |
891 | ||
892 | neh = ext_block_hdr(bh); | |
893 | neh->eh_entries = 0; | |
894 | neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0)); | |
895 | neh->eh_magic = EXT4_EXT_MAGIC; | |
896 | neh->eh_depth = 0; | |
897 | ||
898 | /* move remainder of path[depth] to the new leaf */ | |
899 | if (unlikely(path[depth].p_hdr->eh_entries != | |
900 | path[depth].p_hdr->eh_max)) { | |
901 | EXT4_ERROR_INODE(inode, "eh_entries %d != eh_max %d!", | |
902 | path[depth].p_hdr->eh_entries, | |
903 | path[depth].p_hdr->eh_max); | |
904 | err = -EIO; | |
905 | goto cleanup; | |
906 | } | |
907 | /* start copy from next extent */ | |
908 | m = EXT_MAX_EXTENT(path[depth].p_hdr) - path[depth].p_ext++; | |
909 | ext4_ext_show_move(inode, path, newblock, depth); | |
910 | if (m) { | |
911 | struct ext4_extent *ex; | |
912 | ex = EXT_FIRST_EXTENT(neh); | |
913 | memmove(ex, path[depth].p_ext, sizeof(struct ext4_extent) * m); | |
914 | le16_add_cpu(&neh->eh_entries, m); | |
915 | } | |
916 | ||
917 | set_buffer_uptodate(bh); | |
918 | unlock_buffer(bh); | |
919 | ||
920 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
921 | if (err) | |
922 | goto cleanup; | |
923 | brelse(bh); | |
924 | bh = NULL; | |
925 | ||
926 | /* correct old leaf */ | |
927 | if (m) { | |
928 | err = ext4_ext_get_access(handle, inode, path + depth); | |
929 | if (err) | |
930 | goto cleanup; | |
931 | le16_add_cpu(&path[depth].p_hdr->eh_entries, -m); | |
932 | err = ext4_ext_dirty(handle, inode, path + depth); | |
933 | if (err) | |
934 | goto cleanup; | |
935 | ||
936 | } | |
937 | ||
938 | /* create intermediate indexes */ | |
939 | k = depth - at - 1; | |
940 | if (unlikely(k < 0)) { | |
941 | EXT4_ERROR_INODE(inode, "k %d < 0!", k); | |
942 | err = -EIO; | |
943 | goto cleanup; | |
944 | } | |
945 | if (k) | |
946 | ext_debug("create %d intermediate indices\n", k); | |
947 | /* insert new index into current index block */ | |
948 | /* current depth stored in i var */ | |
949 | i = depth - 1; | |
950 | while (k--) { | |
951 | oldblock = newblock; | |
952 | newblock = ablocks[--a]; | |
953 | bh = sb_getblk(inode->i_sb, newblock); | |
954 | if (!bh) { | |
955 | err = -EIO; | |
956 | goto cleanup; | |
957 | } | |
958 | lock_buffer(bh); | |
959 | ||
960 | err = ext4_journal_get_create_access(handle, bh); | |
961 | if (err) | |
962 | goto cleanup; | |
963 | ||
964 | neh = ext_block_hdr(bh); | |
965 | neh->eh_entries = cpu_to_le16(1); | |
966 | neh->eh_magic = EXT4_EXT_MAGIC; | |
967 | neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0)); | |
968 | neh->eh_depth = cpu_to_le16(depth - i); | |
969 | fidx = EXT_FIRST_INDEX(neh); | |
970 | fidx->ei_block = border; | |
971 | ext4_idx_store_pblock(fidx, oldblock); | |
972 | ||
973 | ext_debug("int.index at %d (block %llu): %u -> %llu\n", | |
974 | i, newblock, le32_to_cpu(border), oldblock); | |
975 | ||
976 | /* move remainder of path[i] to the new index block */ | |
977 | if (unlikely(EXT_MAX_INDEX(path[i].p_hdr) != | |
978 | EXT_LAST_INDEX(path[i].p_hdr))) { | |
979 | EXT4_ERROR_INODE(inode, | |
980 | "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!", | |
981 | le32_to_cpu(path[i].p_ext->ee_block)); | |
982 | err = -EIO; | |
983 | goto cleanup; | |
984 | } | |
985 | /* start copy indexes */ | |
986 | m = EXT_MAX_INDEX(path[i].p_hdr) - path[i].p_idx++; | |
987 | ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx, | |
988 | EXT_MAX_INDEX(path[i].p_hdr)); | |
989 | ext4_ext_show_move(inode, path, newblock, i); | |
990 | if (m) { | |
991 | memmove(++fidx, path[i].p_idx, | |
992 | sizeof(struct ext4_extent_idx) * m); | |
993 | le16_add_cpu(&neh->eh_entries, m); | |
994 | } | |
995 | set_buffer_uptodate(bh); | |
996 | unlock_buffer(bh); | |
997 | ||
998 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
999 | if (err) | |
1000 | goto cleanup; | |
1001 | brelse(bh); | |
1002 | bh = NULL; | |
1003 | ||
1004 | /* correct old index */ | |
1005 | if (m) { | |
1006 | err = ext4_ext_get_access(handle, inode, path + i); | |
1007 | if (err) | |
1008 | goto cleanup; | |
1009 | le16_add_cpu(&path[i].p_hdr->eh_entries, -m); | |
1010 | err = ext4_ext_dirty(handle, inode, path + i); | |
1011 | if (err) | |
1012 | goto cleanup; | |
1013 | } | |
1014 | ||
1015 | i--; | |
1016 | } | |
1017 | ||
1018 | /* insert new index */ | |
1019 | err = ext4_ext_insert_index(handle, inode, path + at, | |
1020 | le32_to_cpu(border), newblock); | |
1021 | ||
1022 | cleanup: | |
1023 | if (bh) { | |
1024 | if (buffer_locked(bh)) | |
1025 | unlock_buffer(bh); | |
1026 | brelse(bh); | |
1027 | } | |
1028 | ||
1029 | if (err) { | |
1030 | /* free all allocated blocks in error case */ | |
1031 | for (i = 0; i < depth; i++) { | |
1032 | if (!ablocks[i]) | |
1033 | continue; | |
1034 | ext4_free_blocks(handle, inode, NULL, ablocks[i], 1, | |
1035 | EXT4_FREE_BLOCKS_METADATA); | |
1036 | } | |
1037 | } | |
1038 | kfree(ablocks); | |
1039 | ||
1040 | return err; | |
1041 | } | |
1042 | ||
1043 | /* | |
1044 | * ext4_ext_grow_indepth: | |
1045 | * implements tree growing procedure: | |
1046 | * - allocates new block | |
1047 | * - moves top-level data (index block or leaf) into the new block | |
1048 | * - initializes new top-level, creating index that points to the | |
1049 | * just created block | |
1050 | */ | |
1051 | static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode, | |
1052 | unsigned int flags, | |
1053 | struct ext4_extent *newext) | |
1054 | { | |
1055 | struct ext4_extent_header *neh; | |
1056 | struct buffer_head *bh; | |
1057 | ext4_fsblk_t newblock; | |
1058 | int err = 0; | |
1059 | ||
1060 | newblock = ext4_ext_new_meta_block(handle, inode, NULL, | |
1061 | newext, &err, flags); | |
1062 | if (newblock == 0) | |
1063 | return err; | |
1064 | ||
1065 | bh = sb_getblk(inode->i_sb, newblock); | |
1066 | if (!bh) { | |
1067 | err = -EIO; | |
1068 | ext4_std_error(inode->i_sb, err); | |
1069 | return err; | |
1070 | } | |
1071 | lock_buffer(bh); | |
1072 | ||
1073 | err = ext4_journal_get_create_access(handle, bh); | |
1074 | if (err) { | |
1075 | unlock_buffer(bh); | |
1076 | goto out; | |
1077 | } | |
1078 | ||
1079 | /* move top-level index/leaf into new block */ | |
1080 | memmove(bh->b_data, EXT4_I(inode)->i_data, | |
1081 | sizeof(EXT4_I(inode)->i_data)); | |
1082 | ||
1083 | /* set size of new block */ | |
1084 | neh = ext_block_hdr(bh); | |
1085 | /* old root could have indexes or leaves | |
1086 | * so calculate e_max right way */ | |
1087 | if (ext_depth(inode)) | |
1088 | neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0)); | |
1089 | else | |
1090 | neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0)); | |
1091 | neh->eh_magic = EXT4_EXT_MAGIC; | |
1092 | set_buffer_uptodate(bh); | |
1093 | unlock_buffer(bh); | |
1094 | ||
1095 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
1096 | if (err) | |
1097 | goto out; | |
1098 | ||
1099 | /* Update top-level index: num,max,pointer */ | |
1100 | neh = ext_inode_hdr(inode); | |
1101 | neh->eh_entries = cpu_to_le16(1); | |
1102 | ext4_idx_store_pblock(EXT_FIRST_INDEX(neh), newblock); | |
1103 | if (neh->eh_depth == 0) { | |
1104 | /* Root extent block becomes index block */ | |
1105 | neh->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode, 0)); | |
1106 | EXT_FIRST_INDEX(neh)->ei_block = | |
1107 | EXT_FIRST_EXTENT(neh)->ee_block; | |
1108 | } | |
1109 | ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n", | |
1110 | le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max), | |
1111 | le32_to_cpu(EXT_FIRST_INDEX(neh)->ei_block), | |
1112 | ext4_idx_pblock(EXT_FIRST_INDEX(neh))); | |
1113 | ||
1114 | neh->eh_depth = cpu_to_le16(neh->eh_depth + 1); | |
1115 | ext4_mark_inode_dirty(handle, inode); | |
1116 | out: | |
1117 | brelse(bh); | |
1118 | ||
1119 | return err; | |
1120 | } | |
1121 | ||
1122 | /* | |
1123 | * ext4_ext_create_new_leaf: | |
1124 | * finds empty index and adds new leaf. | |
1125 | * if no free index is found, then it requests in-depth growing. | |
1126 | */ | |
1127 | static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode, | |
1128 | unsigned int flags, | |
1129 | struct ext4_ext_path *path, | |
1130 | struct ext4_extent *newext) | |
1131 | { | |
1132 | struct ext4_ext_path *curp; | |
1133 | int depth, i, err = 0; | |
1134 | ||
1135 | repeat: | |
1136 | i = depth = ext_depth(inode); | |
1137 | ||
1138 | /* walk up to the tree and look for free index entry */ | |
1139 | curp = path + depth; | |
1140 | while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) { | |
1141 | i--; | |
1142 | curp--; | |
1143 | } | |
1144 | ||
1145 | /* we use already allocated block for index block, | |
1146 | * so subsequent data blocks should be contiguous */ | |
1147 | if (EXT_HAS_FREE_INDEX(curp)) { | |
1148 | /* if we found index with free entry, then use that | |
1149 | * entry: create all needed subtree and add new leaf */ | |
1150 | err = ext4_ext_split(handle, inode, flags, path, newext, i); | |
1151 | if (err) | |
1152 | goto out; | |
1153 | ||
1154 | /* refill path */ | |
1155 | ext4_ext_drop_refs(path); | |
1156 | path = ext4_ext_find_extent(inode, | |
1157 | (ext4_lblk_t)le32_to_cpu(newext->ee_block), | |
1158 | path); | |
1159 | if (IS_ERR(path)) | |
1160 | err = PTR_ERR(path); | |
1161 | } else { | |
1162 | /* tree is full, time to grow in depth */ | |
1163 | err = ext4_ext_grow_indepth(handle, inode, flags, newext); | |
1164 | if (err) | |
1165 | goto out; | |
1166 | ||
1167 | /* refill path */ | |
1168 | ext4_ext_drop_refs(path); | |
1169 | path = ext4_ext_find_extent(inode, | |
1170 | (ext4_lblk_t)le32_to_cpu(newext->ee_block), | |
1171 | path); | |
1172 | if (IS_ERR(path)) { | |
1173 | err = PTR_ERR(path); | |
1174 | goto out; | |
1175 | } | |
1176 | ||
1177 | /* | |
1178 | * only first (depth 0 -> 1) produces free space; | |
1179 | * in all other cases we have to split the grown tree | |
1180 | */ | |
1181 | depth = ext_depth(inode); | |
1182 | if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) { | |
1183 | /* now we need to split */ | |
1184 | goto repeat; | |
1185 | } | |
1186 | } | |
1187 | ||
1188 | out: | |
1189 | return err; | |
1190 | } | |
1191 | ||
1192 | /* | |
1193 | * search the closest allocated block to the left for *logical | |
1194 | * and returns it at @logical + it's physical address at @phys | |
1195 | * if *logical is the smallest allocated block, the function | |
1196 | * returns 0 at @phys | |
1197 | * return value contains 0 (success) or error code | |
1198 | */ | |
1199 | static int ext4_ext_search_left(struct inode *inode, | |
1200 | struct ext4_ext_path *path, | |
1201 | ext4_lblk_t *logical, ext4_fsblk_t *phys) | |
1202 | { | |
1203 | struct ext4_extent_idx *ix; | |
1204 | struct ext4_extent *ex; | |
1205 | int depth, ee_len; | |
1206 | ||
1207 | if (unlikely(path == NULL)) { | |
1208 | EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical); | |
1209 | return -EIO; | |
1210 | } | |
1211 | depth = path->p_depth; | |
1212 | *phys = 0; | |
1213 | ||
1214 | if (depth == 0 && path->p_ext == NULL) | |
1215 | return 0; | |
1216 | ||
1217 | /* usually extent in the path covers blocks smaller | |
1218 | * then *logical, but it can be that extent is the | |
1219 | * first one in the file */ | |
1220 | ||
1221 | ex = path[depth].p_ext; | |
1222 | ee_len = ext4_ext_get_actual_len(ex); | |
1223 | if (*logical < le32_to_cpu(ex->ee_block)) { | |
1224 | if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) { | |
1225 | EXT4_ERROR_INODE(inode, | |
1226 | "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!", | |
1227 | *logical, le32_to_cpu(ex->ee_block)); | |
1228 | return -EIO; | |
1229 | } | |
1230 | while (--depth >= 0) { | |
1231 | ix = path[depth].p_idx; | |
1232 | if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) { | |
1233 | EXT4_ERROR_INODE(inode, | |
1234 | "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!", | |
1235 | ix != NULL ? le32_to_cpu(ix->ei_block) : 0, | |
1236 | EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ? | |
1237 | le32_to_cpu(EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block) : 0, | |
1238 | depth); | |
1239 | return -EIO; | |
1240 | } | |
1241 | } | |
1242 | return 0; | |
1243 | } | |
1244 | ||
1245 | if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) { | |
1246 | EXT4_ERROR_INODE(inode, | |
1247 | "logical %d < ee_block %d + ee_len %d!", | |
1248 | *logical, le32_to_cpu(ex->ee_block), ee_len); | |
1249 | return -EIO; | |
1250 | } | |
1251 | ||
1252 | *logical = le32_to_cpu(ex->ee_block) + ee_len - 1; | |
1253 | *phys = ext4_ext_pblock(ex) + ee_len - 1; | |
1254 | return 0; | |
1255 | } | |
1256 | ||
1257 | /* | |
1258 | * search the closest allocated block to the right for *logical | |
1259 | * and returns it at @logical + it's physical address at @phys | |
1260 | * if *logical is the largest allocated block, the function | |
1261 | * returns 0 at @phys | |
1262 | * return value contains 0 (success) or error code | |
1263 | */ | |
1264 | static int ext4_ext_search_right(struct inode *inode, | |
1265 | struct ext4_ext_path *path, | |
1266 | ext4_lblk_t *logical, ext4_fsblk_t *phys, | |
1267 | struct ext4_extent **ret_ex) | |
1268 | { | |
1269 | struct buffer_head *bh = NULL; | |
1270 | struct ext4_extent_header *eh; | |
1271 | struct ext4_extent_idx *ix; | |
1272 | struct ext4_extent *ex; | |
1273 | ext4_fsblk_t block; | |
1274 | int depth; /* Note, NOT eh_depth; depth from top of tree */ | |
1275 | int ee_len; | |
1276 | ||
1277 | if (unlikely(path == NULL)) { | |
1278 | EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical); | |
1279 | return -EIO; | |
1280 | } | |
1281 | depth = path->p_depth; | |
1282 | *phys = 0; | |
1283 | ||
1284 | if (depth == 0 && path->p_ext == NULL) | |
1285 | return 0; | |
1286 | ||
1287 | /* usually extent in the path covers blocks smaller | |
1288 | * then *logical, but it can be that extent is the | |
1289 | * first one in the file */ | |
1290 | ||
1291 | ex = path[depth].p_ext; | |
1292 | ee_len = ext4_ext_get_actual_len(ex); | |
1293 | if (*logical < le32_to_cpu(ex->ee_block)) { | |
1294 | if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) { | |
1295 | EXT4_ERROR_INODE(inode, | |
1296 | "first_extent(path[%d].p_hdr) != ex", | |
1297 | depth); | |
1298 | return -EIO; | |
1299 | } | |
1300 | while (--depth >= 0) { | |
1301 | ix = path[depth].p_idx; | |
1302 | if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) { | |
1303 | EXT4_ERROR_INODE(inode, | |
1304 | "ix != EXT_FIRST_INDEX *logical %d!", | |
1305 | *logical); | |
1306 | return -EIO; | |
1307 | } | |
1308 | } | |
1309 | goto found_extent; | |
1310 | } | |
1311 | ||
1312 | if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) { | |
1313 | EXT4_ERROR_INODE(inode, | |
1314 | "logical %d < ee_block %d + ee_len %d!", | |
1315 | *logical, le32_to_cpu(ex->ee_block), ee_len); | |
1316 | return -EIO; | |
1317 | } | |
1318 | ||
1319 | if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) { | |
1320 | /* next allocated block in this leaf */ | |
1321 | ex++; | |
1322 | goto found_extent; | |
1323 | } | |
1324 | ||
1325 | /* go up and search for index to the right */ | |
1326 | while (--depth >= 0) { | |
1327 | ix = path[depth].p_idx; | |
1328 | if (ix != EXT_LAST_INDEX(path[depth].p_hdr)) | |
1329 | goto got_index; | |
1330 | } | |
1331 | ||
1332 | /* we've gone up to the root and found no index to the right */ | |
1333 | return 0; | |
1334 | ||
1335 | got_index: | |
1336 | /* we've found index to the right, let's | |
1337 | * follow it and find the closest allocated | |
1338 | * block to the right */ | |
1339 | ix++; | |
1340 | block = ext4_idx_pblock(ix); | |
1341 | while (++depth < path->p_depth) { | |
1342 | bh = sb_bread(inode->i_sb, block); | |
1343 | if (bh == NULL) | |
1344 | return -EIO; | |
1345 | eh = ext_block_hdr(bh); | |
1346 | /* subtract from p_depth to get proper eh_depth */ | |
1347 | if (ext4_ext_check(inode, eh, path->p_depth - depth)) { | |
1348 | put_bh(bh); | |
1349 | return -EIO; | |
1350 | } | |
1351 | ix = EXT_FIRST_INDEX(eh); | |
1352 | block = ext4_idx_pblock(ix); | |
1353 | put_bh(bh); | |
1354 | } | |
1355 | ||
1356 | bh = sb_bread(inode->i_sb, block); | |
1357 | if (bh == NULL) | |
1358 | return -EIO; | |
1359 | eh = ext_block_hdr(bh); | |
1360 | if (ext4_ext_check(inode, eh, path->p_depth - depth)) { | |
1361 | put_bh(bh); | |
1362 | return -EIO; | |
1363 | } | |
1364 | ex = EXT_FIRST_EXTENT(eh); | |
1365 | found_extent: | |
1366 | *logical = le32_to_cpu(ex->ee_block); | |
1367 | *phys = ext4_ext_pblock(ex); | |
1368 | *ret_ex = ex; | |
1369 | if (bh) | |
1370 | put_bh(bh); | |
1371 | return 0; | |
1372 | } | |
1373 | ||
1374 | /* | |
1375 | * ext4_ext_next_allocated_block: | |
1376 | * returns allocated block in subsequent extent or EXT_MAX_BLOCKS. | |
1377 | * NOTE: it considers block number from index entry as | |
1378 | * allocated block. Thus, index entries have to be consistent | |
1379 | * with leaves. | |
1380 | */ | |
1381 | static ext4_lblk_t | |
1382 | ext4_ext_next_allocated_block(struct ext4_ext_path *path) | |
1383 | { | |
1384 | int depth; | |
1385 | ||
1386 | BUG_ON(path == NULL); | |
1387 | depth = path->p_depth; | |
1388 | ||
1389 | if (depth == 0 && path->p_ext == NULL) | |
1390 | return EXT_MAX_BLOCKS; | |
1391 | ||
1392 | while (depth >= 0) { | |
1393 | if (depth == path->p_depth) { | |
1394 | /* leaf */ | |
1395 | if (path[depth].p_ext != | |
1396 | EXT_LAST_EXTENT(path[depth].p_hdr)) | |
1397 | return le32_to_cpu(path[depth].p_ext[1].ee_block); | |
1398 | } else { | |
1399 | /* index */ | |
1400 | if (path[depth].p_idx != | |
1401 | EXT_LAST_INDEX(path[depth].p_hdr)) | |
1402 | return le32_to_cpu(path[depth].p_idx[1].ei_block); | |
1403 | } | |
1404 | depth--; | |
1405 | } | |
1406 | ||
1407 | return EXT_MAX_BLOCKS; | |
1408 | } | |
1409 | ||
1410 | /* | |
1411 | * ext4_ext_next_leaf_block: | |
1412 | * returns first allocated block from next leaf or EXT_MAX_BLOCKS | |
1413 | */ | |
1414 | static ext4_lblk_t ext4_ext_next_leaf_block(struct ext4_ext_path *path) | |
1415 | { | |
1416 | int depth; | |
1417 | ||
1418 | BUG_ON(path == NULL); | |
1419 | depth = path->p_depth; | |
1420 | ||
1421 | /* zero-tree has no leaf blocks at all */ | |
1422 | if (depth == 0) | |
1423 | return EXT_MAX_BLOCKS; | |
1424 | ||
1425 | /* go to index block */ | |
1426 | depth--; | |
1427 | ||
1428 | while (depth >= 0) { | |
1429 | if (path[depth].p_idx != | |
1430 | EXT_LAST_INDEX(path[depth].p_hdr)) | |
1431 | return (ext4_lblk_t) | |
1432 | le32_to_cpu(path[depth].p_idx[1].ei_block); | |
1433 | depth--; | |
1434 | } | |
1435 | ||
1436 | return EXT_MAX_BLOCKS; | |
1437 | } | |
1438 | ||
1439 | /* | |
1440 | * ext4_ext_correct_indexes: | |
1441 | * if leaf gets modified and modified extent is first in the leaf, | |
1442 | * then we have to correct all indexes above. | |
1443 | * TODO: do we need to correct tree in all cases? | |
1444 | */ | |
1445 | static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode, | |
1446 | struct ext4_ext_path *path) | |
1447 | { | |
1448 | struct ext4_extent_header *eh; | |
1449 | int depth = ext_depth(inode); | |
1450 | struct ext4_extent *ex; | |
1451 | __le32 border; | |
1452 | int k, err = 0; | |
1453 | ||
1454 | eh = path[depth].p_hdr; | |
1455 | ex = path[depth].p_ext; | |
1456 | ||
1457 | if (unlikely(ex == NULL || eh == NULL)) { | |
1458 | EXT4_ERROR_INODE(inode, | |
1459 | "ex %p == NULL or eh %p == NULL", ex, eh); | |
1460 | return -EIO; | |
1461 | } | |
1462 | ||
1463 | if (depth == 0) { | |
1464 | /* there is no tree at all */ | |
1465 | return 0; | |
1466 | } | |
1467 | ||
1468 | if (ex != EXT_FIRST_EXTENT(eh)) { | |
1469 | /* we correct tree if first leaf got modified only */ | |
1470 | return 0; | |
1471 | } | |
1472 | ||
1473 | /* | |
1474 | * TODO: we need correction if border is smaller than current one | |
1475 | */ | |
1476 | k = depth - 1; | |
1477 | border = path[depth].p_ext->ee_block; | |
1478 | err = ext4_ext_get_access(handle, inode, path + k); | |
1479 | if (err) | |
1480 | return err; | |
1481 | path[k].p_idx->ei_block = border; | |
1482 | err = ext4_ext_dirty(handle, inode, path + k); | |
1483 | if (err) | |
1484 | return err; | |
1485 | ||
1486 | while (k--) { | |
1487 | /* change all left-side indexes */ | |
1488 | if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr)) | |
1489 | break; | |
1490 | err = ext4_ext_get_access(handle, inode, path + k); | |
1491 | if (err) | |
1492 | break; | |
1493 | path[k].p_idx->ei_block = border; | |
1494 | err = ext4_ext_dirty(handle, inode, path + k); | |
1495 | if (err) | |
1496 | break; | |
1497 | } | |
1498 | ||
1499 | return err; | |
1500 | } | |
1501 | ||
1502 | int | |
1503 | ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, | |
1504 | struct ext4_extent *ex2) | |
1505 | { | |
1506 | unsigned short ext1_ee_len, ext2_ee_len, max_len; | |
1507 | ||
1508 | /* | |
1509 | * Make sure that either both extents are uninitialized, or | |
1510 | * both are _not_. | |
1511 | */ | |
1512 | if (ext4_ext_is_uninitialized(ex1) ^ ext4_ext_is_uninitialized(ex2)) | |
1513 | return 0; | |
1514 | ||
1515 | if (ext4_ext_is_uninitialized(ex1)) | |
1516 | max_len = EXT_UNINIT_MAX_LEN; | |
1517 | else | |
1518 | max_len = EXT_INIT_MAX_LEN; | |
1519 | ||
1520 | ext1_ee_len = ext4_ext_get_actual_len(ex1); | |
1521 | ext2_ee_len = ext4_ext_get_actual_len(ex2); | |
1522 | ||
1523 | if (le32_to_cpu(ex1->ee_block) + ext1_ee_len != | |
1524 | le32_to_cpu(ex2->ee_block)) | |
1525 | return 0; | |
1526 | ||
1527 | /* | |
1528 | * To allow future support for preallocated extents to be added | |
1529 | * as an RO_COMPAT feature, refuse to merge to extents if | |
1530 | * this can result in the top bit of ee_len being set. | |
1531 | */ | |
1532 | if (ext1_ee_len + ext2_ee_len > max_len) | |
1533 | return 0; | |
1534 | #ifdef AGGRESSIVE_TEST | |
1535 | if (ext1_ee_len >= 4) | |
1536 | return 0; | |
1537 | #endif | |
1538 | ||
1539 | if (ext4_ext_pblock(ex1) + ext1_ee_len == ext4_ext_pblock(ex2)) | |
1540 | return 1; | |
1541 | return 0; | |
1542 | } | |
1543 | ||
1544 | /* | |
1545 | * This function tries to merge the "ex" extent to the next extent in the tree. | |
1546 | * It always tries to merge towards right. If you want to merge towards | |
1547 | * left, pass "ex - 1" as argument instead of "ex". | |
1548 | * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns | |
1549 | * 1 if they got merged. | |
1550 | */ | |
1551 | static int ext4_ext_try_to_merge_right(struct inode *inode, | |
1552 | struct ext4_ext_path *path, | |
1553 | struct ext4_extent *ex) | |
1554 | { | |
1555 | struct ext4_extent_header *eh; | |
1556 | unsigned int depth, len; | |
1557 | int merge_done = 0; | |
1558 | int uninitialized = 0; | |
1559 | ||
1560 | depth = ext_depth(inode); | |
1561 | BUG_ON(path[depth].p_hdr == NULL); | |
1562 | eh = path[depth].p_hdr; | |
1563 | ||
1564 | while (ex < EXT_LAST_EXTENT(eh)) { | |
1565 | if (!ext4_can_extents_be_merged(inode, ex, ex + 1)) | |
1566 | break; | |
1567 | /* merge with next extent! */ | |
1568 | if (ext4_ext_is_uninitialized(ex)) | |
1569 | uninitialized = 1; | |
1570 | ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex) | |
1571 | + ext4_ext_get_actual_len(ex + 1)); | |
1572 | if (uninitialized) | |
1573 | ext4_ext_mark_uninitialized(ex); | |
1574 | ||
1575 | if (ex + 1 < EXT_LAST_EXTENT(eh)) { | |
1576 | len = (EXT_LAST_EXTENT(eh) - ex - 1) | |
1577 | * sizeof(struct ext4_extent); | |
1578 | memmove(ex + 1, ex + 2, len); | |
1579 | } | |
1580 | le16_add_cpu(&eh->eh_entries, -1); | |
1581 | merge_done = 1; | |
1582 | WARN_ON(eh->eh_entries == 0); | |
1583 | if (!eh->eh_entries) | |
1584 | EXT4_ERROR_INODE(inode, "eh->eh_entries = 0!"); | |
1585 | } | |
1586 | ||
1587 | return merge_done; | |
1588 | } | |
1589 | ||
1590 | /* | |
1591 | * This function tries to merge the @ex extent to neighbours in the tree. | |
1592 | * return 1 if merge left else 0. | |
1593 | */ | |
1594 | static int ext4_ext_try_to_merge(struct inode *inode, | |
1595 | struct ext4_ext_path *path, | |
1596 | struct ext4_extent *ex) { | |
1597 | struct ext4_extent_header *eh; | |
1598 | unsigned int depth; | |
1599 | int merge_done = 0; | |
1600 | int ret = 0; | |
1601 | ||
1602 | depth = ext_depth(inode); | |
1603 | BUG_ON(path[depth].p_hdr == NULL); | |
1604 | eh = path[depth].p_hdr; | |
1605 | ||
1606 | if (ex > EXT_FIRST_EXTENT(eh)) | |
1607 | merge_done = ext4_ext_try_to_merge_right(inode, path, ex - 1); | |
1608 | ||
1609 | if (!merge_done) | |
1610 | ret = ext4_ext_try_to_merge_right(inode, path, ex); | |
1611 | ||
1612 | return ret; | |
1613 | } | |
1614 | ||
1615 | /* | |
1616 | * check if a portion of the "newext" extent overlaps with an | |
1617 | * existing extent. | |
1618 | * | |
1619 | * If there is an overlap discovered, it updates the length of the newext | |
1620 | * such that there will be no overlap, and then returns 1. | |
1621 | * If there is no overlap found, it returns 0. | |
1622 | */ | |
1623 | static unsigned int ext4_ext_check_overlap(struct ext4_sb_info *sbi, | |
1624 | struct inode *inode, | |
1625 | struct ext4_extent *newext, | |
1626 | struct ext4_ext_path *path) | |
1627 | { | |
1628 | ext4_lblk_t b1, b2; | |
1629 | unsigned int depth, len1; | |
1630 | unsigned int ret = 0; | |
1631 | ||
1632 | b1 = le32_to_cpu(newext->ee_block); | |
1633 | len1 = ext4_ext_get_actual_len(newext); | |
1634 | depth = ext_depth(inode); | |
1635 | if (!path[depth].p_ext) | |
1636 | goto out; | |
1637 | b2 = le32_to_cpu(path[depth].p_ext->ee_block); | |
1638 | b2 &= ~(sbi->s_cluster_ratio - 1); | |
1639 | ||
1640 | /* | |
1641 | * get the next allocated block if the extent in the path | |
1642 | * is before the requested block(s) | |
1643 | */ | |
1644 | if (b2 < b1) { | |
1645 | b2 = ext4_ext_next_allocated_block(path); | |
1646 | if (b2 == EXT_MAX_BLOCKS) | |
1647 | goto out; | |
1648 | b2 &= ~(sbi->s_cluster_ratio - 1); | |
1649 | } | |
1650 | ||
1651 | /* check for wrap through zero on extent logical start block*/ | |
1652 | if (b1 + len1 < b1) { | |
1653 | len1 = EXT_MAX_BLOCKS - b1; | |
1654 | newext->ee_len = cpu_to_le16(len1); | |
1655 | ret = 1; | |
1656 | } | |
1657 | ||
1658 | /* check for overlap */ | |
1659 | if (b1 + len1 > b2) { | |
1660 | newext->ee_len = cpu_to_le16(b2 - b1); | |
1661 | ret = 1; | |
1662 | } | |
1663 | out: | |
1664 | return ret; | |
1665 | } | |
1666 | ||
1667 | /* | |
1668 | * ext4_ext_insert_extent: | |
1669 | * tries to merge requsted extent into the existing extent or | |
1670 | * inserts requested extent as new one into the tree, | |
1671 | * creating new leaf in the no-space case. | |
1672 | */ | |
1673 | int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, | |
1674 | struct ext4_ext_path *path, | |
1675 | struct ext4_extent *newext, int flag) | |
1676 | { | |
1677 | struct ext4_extent_header *eh; | |
1678 | struct ext4_extent *ex, *fex; | |
1679 | struct ext4_extent *nearex; /* nearest extent */ | |
1680 | struct ext4_ext_path *npath = NULL; | |
1681 | int depth, len, err; | |
1682 | ext4_lblk_t next; | |
1683 | unsigned uninitialized = 0; | |
1684 | int flags = 0; | |
1685 | ||
1686 | if (unlikely(ext4_ext_get_actual_len(newext) == 0)) { | |
1687 | EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0"); | |
1688 | return -EIO; | |
1689 | } | |
1690 | depth = ext_depth(inode); | |
1691 | ex = path[depth].p_ext; | |
1692 | if (unlikely(path[depth].p_hdr == NULL)) { | |
1693 | EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth); | |
1694 | return -EIO; | |
1695 | } | |
1696 | ||
1697 | /* try to insert block into found extent and return */ | |
1698 | if (ex && !(flag & EXT4_GET_BLOCKS_PRE_IO) | |
1699 | && ext4_can_extents_be_merged(inode, ex, newext)) { | |
1700 | ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n", | |
1701 | ext4_ext_is_uninitialized(newext), | |
1702 | ext4_ext_get_actual_len(newext), | |
1703 | le32_to_cpu(ex->ee_block), | |
1704 | ext4_ext_is_uninitialized(ex), | |
1705 | ext4_ext_get_actual_len(ex), | |
1706 | ext4_ext_pblock(ex)); | |
1707 | err = ext4_ext_get_access(handle, inode, path + depth); | |
1708 | if (err) | |
1709 | return err; | |
1710 | ||
1711 | /* | |
1712 | * ext4_can_extents_be_merged should have checked that either | |
1713 | * both extents are uninitialized, or both aren't. Thus we | |
1714 | * need to check only one of them here. | |
1715 | */ | |
1716 | if (ext4_ext_is_uninitialized(ex)) | |
1717 | uninitialized = 1; | |
1718 | ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex) | |
1719 | + ext4_ext_get_actual_len(newext)); | |
1720 | if (uninitialized) | |
1721 | ext4_ext_mark_uninitialized(ex); | |
1722 | eh = path[depth].p_hdr; | |
1723 | nearex = ex; | |
1724 | goto merge; | |
1725 | } | |
1726 | ||
1727 | depth = ext_depth(inode); | |
1728 | eh = path[depth].p_hdr; | |
1729 | if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) | |
1730 | goto has_space; | |
1731 | ||
1732 | /* probably next leaf has space for us? */ | |
1733 | fex = EXT_LAST_EXTENT(eh); | |
1734 | next = EXT_MAX_BLOCKS; | |
1735 | if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block)) | |
1736 | next = ext4_ext_next_leaf_block(path); | |
1737 | if (next != EXT_MAX_BLOCKS) { | |
1738 | ext_debug("next leaf block - %d\n", next); | |
1739 | BUG_ON(npath != NULL); | |
1740 | npath = ext4_ext_find_extent(inode, next, NULL); | |
1741 | if (IS_ERR(npath)) | |
1742 | return PTR_ERR(npath); | |
1743 | BUG_ON(npath->p_depth != path->p_depth); | |
1744 | eh = npath[depth].p_hdr; | |
1745 | if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) { | |
1746 | ext_debug("next leaf isn't full(%d)\n", | |
1747 | le16_to_cpu(eh->eh_entries)); | |
1748 | path = npath; | |
1749 | goto has_space; | |
1750 | } | |
1751 | ext_debug("next leaf has no free space(%d,%d)\n", | |
1752 | le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max)); | |
1753 | } | |
1754 | ||
1755 | /* | |
1756 | * There is no free space in the found leaf. | |
1757 | * We're gonna add a new leaf in the tree. | |
1758 | */ | |
1759 | if (flag & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) | |
1760 | flags = EXT4_MB_USE_ROOT_BLOCKS; | |
1761 | err = ext4_ext_create_new_leaf(handle, inode, flags, path, newext); | |
1762 | if (err) | |
1763 | goto cleanup; | |
1764 | depth = ext_depth(inode); | |
1765 | eh = path[depth].p_hdr; | |
1766 | ||
1767 | has_space: | |
1768 | nearex = path[depth].p_ext; | |
1769 | ||
1770 | err = ext4_ext_get_access(handle, inode, path + depth); | |
1771 | if (err) | |
1772 | goto cleanup; | |
1773 | ||
1774 | if (!nearex) { | |
1775 | /* there is no extent in this leaf, create first one */ | |
1776 | ext_debug("first extent in the leaf: %d:%llu:[%d]%d\n", | |
1777 | le32_to_cpu(newext->ee_block), | |
1778 | ext4_ext_pblock(newext), | |
1779 | ext4_ext_is_uninitialized(newext), | |
1780 | ext4_ext_get_actual_len(newext)); | |
1781 | path[depth].p_ext = EXT_FIRST_EXTENT(eh); | |
1782 | } else if (le32_to_cpu(newext->ee_block) | |
1783 | > le32_to_cpu(nearex->ee_block)) { | |
1784 | /* BUG_ON(newext->ee_block == nearex->ee_block); */ | |
1785 | if (nearex != EXT_LAST_EXTENT(eh)) { | |
1786 | len = EXT_MAX_EXTENT(eh) - nearex; | |
1787 | len = (len - 1) * sizeof(struct ext4_extent); | |
1788 | len = len < 0 ? 0 : len; | |
1789 | ext_debug("insert %d:%llu:[%d]%d after: nearest 0x%p, " | |
1790 | "move %d from 0x%p to 0x%p\n", | |
1791 | le32_to_cpu(newext->ee_block), | |
1792 | ext4_ext_pblock(newext), | |
1793 | ext4_ext_is_uninitialized(newext), | |
1794 | ext4_ext_get_actual_len(newext), | |
1795 | nearex, len, nearex + 1, nearex + 2); | |
1796 | memmove(nearex + 2, nearex + 1, len); | |
1797 | } | |
1798 | path[depth].p_ext = nearex + 1; | |
1799 | } else { | |
1800 | BUG_ON(newext->ee_block == nearex->ee_block); | |
1801 | len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent); | |
1802 | len = len < 0 ? 0 : len; | |
1803 | ext_debug("insert %d:%llu:[%d]%d before: nearest 0x%p, " | |
1804 | "move %d from 0x%p to 0x%p\n", | |
1805 | le32_to_cpu(newext->ee_block), | |
1806 | ext4_ext_pblock(newext), | |
1807 | ext4_ext_is_uninitialized(newext), | |
1808 | ext4_ext_get_actual_len(newext), | |
1809 | nearex, len, nearex, nearex + 1); | |
1810 | memmove(nearex + 1, nearex, len); | |
1811 | path[depth].p_ext = nearex; | |
1812 | } | |
1813 | ||
1814 | le16_add_cpu(&eh->eh_entries, 1); | |
1815 | nearex = path[depth].p_ext; | |
1816 | nearex->ee_block = newext->ee_block; | |
1817 | ext4_ext_store_pblock(nearex, ext4_ext_pblock(newext)); | |
1818 | nearex->ee_len = newext->ee_len; | |
1819 | ||
1820 | merge: | |
1821 | /* try to merge extents to the right */ | |
1822 | if (!(flag & EXT4_GET_BLOCKS_PRE_IO)) | |
1823 | ext4_ext_try_to_merge(inode, path, nearex); | |
1824 | ||
1825 | /* try to merge extents to the left */ | |
1826 | ||
1827 | /* time to correct all indexes above */ | |
1828 | err = ext4_ext_correct_indexes(handle, inode, path); | |
1829 | if (err) | |
1830 | goto cleanup; | |
1831 | ||
1832 | err = ext4_ext_dirty(handle, inode, path + depth); | |
1833 | ||
1834 | cleanup: | |
1835 | if (npath) { | |
1836 | ext4_ext_drop_refs(npath); | |
1837 | kfree(npath); | |
1838 | } | |
1839 | ext4_ext_invalidate_cache(inode); | |
1840 | return err; | |
1841 | } | |
1842 | ||
1843 | static int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block, | |
1844 | ext4_lblk_t num, ext_prepare_callback func, | |
1845 | void *cbdata) | |
1846 | { | |
1847 | struct ext4_ext_path *path = NULL; | |
1848 | struct ext4_ext_cache cbex; | |
1849 | struct ext4_extent *ex; | |
1850 | ext4_lblk_t next, start = 0, end = 0; | |
1851 | ext4_lblk_t last = block + num; | |
1852 | int depth, exists, err = 0; | |
1853 | ||
1854 | BUG_ON(func == NULL); | |
1855 | BUG_ON(inode == NULL); | |
1856 | ||
1857 | while (block < last && block != EXT_MAX_BLOCKS) { | |
1858 | num = last - block; | |
1859 | /* find extent for this block */ | |
1860 | down_read(&EXT4_I(inode)->i_data_sem); | |
1861 | path = ext4_ext_find_extent(inode, block, path); | |
1862 | up_read(&EXT4_I(inode)->i_data_sem); | |
1863 | if (IS_ERR(path)) { | |
1864 | err = PTR_ERR(path); | |
1865 | path = NULL; | |
1866 | break; | |
1867 | } | |
1868 | ||
1869 | depth = ext_depth(inode); | |
1870 | if (unlikely(path[depth].p_hdr == NULL)) { | |
1871 | EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth); | |
1872 | err = -EIO; | |
1873 | break; | |
1874 | } | |
1875 | ex = path[depth].p_ext; | |
1876 | next = ext4_ext_next_allocated_block(path); | |
1877 | ||
1878 | exists = 0; | |
1879 | if (!ex) { | |
1880 | /* there is no extent yet, so try to allocate | |
1881 | * all requested space */ | |
1882 | start = block; | |
1883 | end = block + num; | |
1884 | } else if (le32_to_cpu(ex->ee_block) > block) { | |
1885 | /* need to allocate space before found extent */ | |
1886 | start = block; | |
1887 | end = le32_to_cpu(ex->ee_block); | |
1888 | if (block + num < end) | |
1889 | end = block + num; | |
1890 | } else if (block >= le32_to_cpu(ex->ee_block) | |
1891 | + ext4_ext_get_actual_len(ex)) { | |
1892 | /* need to allocate space after found extent */ | |
1893 | start = block; | |
1894 | end = block + num; | |
1895 | if (end >= next) | |
1896 | end = next; | |
1897 | } else if (block >= le32_to_cpu(ex->ee_block)) { | |
1898 | /* | |
1899 | * some part of requested space is covered | |
1900 | * by found extent | |
1901 | */ | |
1902 | start = block; | |
1903 | end = le32_to_cpu(ex->ee_block) | |
1904 | + ext4_ext_get_actual_len(ex); | |
1905 | if (block + num < end) | |
1906 | end = block + num; | |
1907 | exists = 1; | |
1908 | } else { | |
1909 | BUG(); | |
1910 | } | |
1911 | BUG_ON(end <= start); | |
1912 | ||
1913 | if (!exists) { | |
1914 | cbex.ec_block = start; | |
1915 | cbex.ec_len = end - start; | |
1916 | cbex.ec_start = 0; | |
1917 | } else { | |
1918 | cbex.ec_block = le32_to_cpu(ex->ee_block); | |
1919 | cbex.ec_len = ext4_ext_get_actual_len(ex); | |
1920 | cbex.ec_start = ext4_ext_pblock(ex); | |
1921 | } | |
1922 | ||
1923 | if (unlikely(cbex.ec_len == 0)) { | |
1924 | EXT4_ERROR_INODE(inode, "cbex.ec_len == 0"); | |
1925 | err = -EIO; | |
1926 | break; | |
1927 | } | |
1928 | err = func(inode, next, &cbex, ex, cbdata); | |
1929 | ext4_ext_drop_refs(path); | |
1930 | ||
1931 | if (err < 0) | |
1932 | break; | |
1933 | ||
1934 | if (err == EXT_REPEAT) | |
1935 | continue; | |
1936 | else if (err == EXT_BREAK) { | |
1937 | err = 0; | |
1938 | break; | |
1939 | } | |
1940 | ||
1941 | if (ext_depth(inode) != depth) { | |
1942 | /* depth was changed. we have to realloc path */ | |
1943 | kfree(path); | |
1944 | path = NULL; | |
1945 | } | |
1946 | ||
1947 | block = cbex.ec_block + cbex.ec_len; | |
1948 | } | |
1949 | ||
1950 | if (path) { | |
1951 | ext4_ext_drop_refs(path); | |
1952 | kfree(path); | |
1953 | } | |
1954 | ||
1955 | return err; | |
1956 | } | |
1957 | ||
1958 | static void | |
1959 | ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block, | |
1960 | __u32 len, ext4_fsblk_t start) | |
1961 | { | |
1962 | struct ext4_ext_cache *cex; | |
1963 | BUG_ON(len == 0); | |
1964 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
1965 | trace_ext4_ext_put_in_cache(inode, block, len, start); | |
1966 | cex = &EXT4_I(inode)->i_cached_extent; | |
1967 | cex->ec_block = block; | |
1968 | cex->ec_len = len; | |
1969 | cex->ec_start = start; | |
1970 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1971 | } | |
1972 | ||
1973 | /* | |
1974 | * ext4_ext_put_gap_in_cache: | |
1975 | * calculate boundaries of the gap that the requested block fits into | |
1976 | * and cache this gap | |
1977 | */ | |
1978 | static void | |
1979 | ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path, | |
1980 | ext4_lblk_t block) | |
1981 | { | |
1982 | int depth = ext_depth(inode); | |
1983 | unsigned long len; | |
1984 | ext4_lblk_t lblock; | |
1985 | struct ext4_extent *ex; | |
1986 | ||
1987 | ex = path[depth].p_ext; | |
1988 | if (ex == NULL) { | |
1989 | /* there is no extent yet, so gap is [0;-] */ | |
1990 | lblock = 0; | |
1991 | len = EXT_MAX_BLOCKS; | |
1992 | ext_debug("cache gap(whole file):"); | |
1993 | } else if (block < le32_to_cpu(ex->ee_block)) { | |
1994 | lblock = block; | |
1995 | len = le32_to_cpu(ex->ee_block) - block; | |
1996 | ext_debug("cache gap(before): %u [%u:%u]", | |
1997 | block, | |
1998 | le32_to_cpu(ex->ee_block), | |
1999 | ext4_ext_get_actual_len(ex)); | |
2000 | } else if (block >= le32_to_cpu(ex->ee_block) | |
2001 | + ext4_ext_get_actual_len(ex)) { | |
2002 | ext4_lblk_t next; | |
2003 | lblock = le32_to_cpu(ex->ee_block) | |
2004 | + ext4_ext_get_actual_len(ex); | |
2005 | ||
2006 | next = ext4_ext_next_allocated_block(path); | |
2007 | ext_debug("cache gap(after): [%u:%u] %u", | |
2008 | le32_to_cpu(ex->ee_block), | |
2009 | ext4_ext_get_actual_len(ex), | |
2010 | block); | |
2011 | BUG_ON(next == lblock); | |
2012 | len = next - lblock; | |
2013 | } else { | |
2014 | lblock = len = 0; | |
2015 | BUG(); | |
2016 | } | |
2017 | ||
2018 | ext_debug(" -> %u:%lu\n", lblock, len); | |
2019 | ext4_ext_put_in_cache(inode, lblock, len, 0); | |
2020 | } | |
2021 | ||
2022 | /* | |
2023 | * ext4_ext_check_cache() | |
2024 | * Checks to see if the given block is in the cache. | |
2025 | * If it is, the cached extent is stored in the given | |
2026 | * cache extent pointer. If the cached extent is a hole, | |
2027 | * this routine should be used instead of | |
2028 | * ext4_ext_in_cache if the calling function needs to | |
2029 | * know the size of the hole. | |
2030 | * | |
2031 | * @inode: The files inode | |
2032 | * @block: The block to look for in the cache | |
2033 | * @ex: Pointer where the cached extent will be stored | |
2034 | * if it contains block | |
2035 | * | |
2036 | * Return 0 if cache is invalid; 1 if the cache is valid | |
2037 | */ | |
2038 | static int ext4_ext_check_cache(struct inode *inode, ext4_lblk_t block, | |
2039 | struct ext4_ext_cache *ex){ | |
2040 | struct ext4_ext_cache *cex; | |
2041 | struct ext4_sb_info *sbi; | |
2042 | int ret = 0; | |
2043 | ||
2044 | /* | |
2045 | * We borrow i_block_reservation_lock to protect i_cached_extent | |
2046 | */ | |
2047 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
2048 | cex = &EXT4_I(inode)->i_cached_extent; | |
2049 | sbi = EXT4_SB(inode->i_sb); | |
2050 | ||
2051 | /* has cache valid data? */ | |
2052 | if (cex->ec_len == 0) | |
2053 | goto errout; | |
2054 | ||
2055 | if (in_range(block, cex->ec_block, cex->ec_len)) { | |
2056 | memcpy(ex, cex, sizeof(struct ext4_ext_cache)); | |
2057 | ext_debug("%u cached by %u:%u:%llu\n", | |
2058 | block, | |
2059 | cex->ec_block, cex->ec_len, cex->ec_start); | |
2060 | ret = 1; | |
2061 | } | |
2062 | errout: | |
2063 | if (!ret) | |
2064 | sbi->extent_cache_misses++; | |
2065 | else | |
2066 | sbi->extent_cache_hits++; | |
2067 | trace_ext4_ext_in_cache(inode, block, ret); | |
2068 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
2069 | return ret; | |
2070 | } | |
2071 | ||
2072 | /* | |
2073 | * ext4_ext_in_cache() | |
2074 | * Checks to see if the given block is in the cache. | |
2075 | * If it is, the cached extent is stored in the given | |
2076 | * extent pointer. | |
2077 | * | |
2078 | * @inode: The files inode | |
2079 | * @block: The block to look for in the cache | |
2080 | * @ex: Pointer where the cached extent will be stored | |
2081 | * if it contains block | |
2082 | * | |
2083 | * Return 0 if cache is invalid; 1 if the cache is valid | |
2084 | */ | |
2085 | static int | |
2086 | ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block, | |
2087 | struct ext4_extent *ex) | |
2088 | { | |
2089 | struct ext4_ext_cache cex; | |
2090 | int ret = 0; | |
2091 | ||
2092 | if (ext4_ext_check_cache(inode, block, &cex)) { | |
2093 | ex->ee_block = cpu_to_le32(cex.ec_block); | |
2094 | ext4_ext_store_pblock(ex, cex.ec_start); | |
2095 | ex->ee_len = cpu_to_le16(cex.ec_len); | |
2096 | ret = 1; | |
2097 | } | |
2098 | ||
2099 | return ret; | |
2100 | } | |
2101 | ||
2102 | ||
2103 | /* | |
2104 | * ext4_ext_rm_idx: | |
2105 | * removes index from the index block. | |
2106 | */ | |
2107 | static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode, | |
2108 | struct ext4_ext_path *path) | |
2109 | { | |
2110 | int err; | |
2111 | ext4_fsblk_t leaf; | |
2112 | ||
2113 | /* free index block */ | |
2114 | path--; | |
2115 | leaf = ext4_idx_pblock(path->p_idx); | |
2116 | if (unlikely(path->p_hdr->eh_entries == 0)) { | |
2117 | EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0"); | |
2118 | return -EIO; | |
2119 | } | |
2120 | err = ext4_ext_get_access(handle, inode, path); | |
2121 | if (err) | |
2122 | return err; | |
2123 | ||
2124 | if (path->p_idx != EXT_LAST_INDEX(path->p_hdr)) { | |
2125 | int len = EXT_LAST_INDEX(path->p_hdr) - path->p_idx; | |
2126 | len *= sizeof(struct ext4_extent_idx); | |
2127 | memmove(path->p_idx, path->p_idx + 1, len); | |
2128 | } | |
2129 | ||
2130 | le16_add_cpu(&path->p_hdr->eh_entries, -1); | |
2131 | err = ext4_ext_dirty(handle, inode, path); | |
2132 | if (err) | |
2133 | return err; | |
2134 | ext_debug("index is empty, remove it, free block %llu\n", leaf); | |
2135 | trace_ext4_ext_rm_idx(inode, leaf); | |
2136 | ||
2137 | ext4_free_blocks(handle, inode, NULL, leaf, 1, | |
2138 | EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET); | |
2139 | return err; | |
2140 | } | |
2141 | ||
2142 | /* | |
2143 | * ext4_ext_calc_credits_for_single_extent: | |
2144 | * This routine returns max. credits that needed to insert an extent | |
2145 | * to the extent tree. | |
2146 | * When pass the actual path, the caller should calculate credits | |
2147 | * under i_data_sem. | |
2148 | */ | |
2149 | int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks, | |
2150 | struct ext4_ext_path *path) | |
2151 | { | |
2152 | if (path) { | |
2153 | int depth = ext_depth(inode); | |
2154 | int ret = 0; | |
2155 | ||
2156 | /* probably there is space in leaf? */ | |
2157 | if (le16_to_cpu(path[depth].p_hdr->eh_entries) | |
2158 | < le16_to_cpu(path[depth].p_hdr->eh_max)) { | |
2159 | ||
2160 | /* | |
2161 | * There are some space in the leaf tree, no | |
2162 | * need to account for leaf block credit | |
2163 | * | |
2164 | * bitmaps and block group descriptor blocks | |
2165 | * and other metadata blocks still need to be | |
2166 | * accounted. | |
2167 | */ | |
2168 | /* 1 bitmap, 1 block group descriptor */ | |
2169 | ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb); | |
2170 | return ret; | |
2171 | } | |
2172 | } | |
2173 | ||
2174 | return ext4_chunk_trans_blocks(inode, nrblocks); | |
2175 | } | |
2176 | ||
2177 | /* | |
2178 | * How many index/leaf blocks need to change/allocate to modify nrblocks? | |
2179 | * | |
2180 | * if nrblocks are fit in a single extent (chunk flag is 1), then | |
2181 | * in the worse case, each tree level index/leaf need to be changed | |
2182 | * if the tree split due to insert a new extent, then the old tree | |
2183 | * index/leaf need to be updated too | |
2184 | * | |
2185 | * If the nrblocks are discontiguous, they could cause | |
2186 | * the whole tree split more than once, but this is really rare. | |
2187 | */ | |
2188 | int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
2189 | { | |
2190 | int index; | |
2191 | int depth = ext_depth(inode); | |
2192 | ||
2193 | if (chunk) | |
2194 | index = depth * 2; | |
2195 | else | |
2196 | index = depth * 3; | |
2197 | ||
2198 | return index; | |
2199 | } | |
2200 | ||
2201 | static int ext4_remove_blocks(handle_t *handle, struct inode *inode, | |
2202 | struct ext4_extent *ex, | |
2203 | ext4_fsblk_t *partial_cluster, | |
2204 | ext4_lblk_t from, ext4_lblk_t to) | |
2205 | { | |
2206 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
2207 | unsigned short ee_len = ext4_ext_get_actual_len(ex); | |
2208 | ext4_fsblk_t pblk; | |
2209 | int flags = EXT4_FREE_BLOCKS_FORGET; | |
2210 | ||
2211 | if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) | |
2212 | flags |= EXT4_FREE_BLOCKS_METADATA; | |
2213 | /* | |
2214 | * For bigalloc file systems, we never free a partial cluster | |
2215 | * at the beginning of the extent. Instead, we make a note | |
2216 | * that we tried freeing the cluster, and check to see if we | |
2217 | * need to free it on a subsequent call to ext4_remove_blocks, | |
2218 | * or at the end of the ext4_truncate() operation. | |
2219 | */ | |
2220 | flags |= EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER; | |
2221 | ||
2222 | trace_ext4_remove_blocks(inode, ex, from, to, *partial_cluster); | |
2223 | /* | |
2224 | * If we have a partial cluster, and it's different from the | |
2225 | * cluster of the last block, we need to explicitly free the | |
2226 | * partial cluster here. | |
2227 | */ | |
2228 | pblk = ext4_ext_pblock(ex) + ee_len - 1; | |
2229 | if (*partial_cluster && (EXT4_B2C(sbi, pblk) != *partial_cluster)) { | |
2230 | ext4_free_blocks(handle, inode, NULL, | |
2231 | EXT4_C2B(sbi, *partial_cluster), | |
2232 | sbi->s_cluster_ratio, flags); | |
2233 | *partial_cluster = 0; | |
2234 | } | |
2235 | ||
2236 | #ifdef EXTENTS_STATS | |
2237 | { | |
2238 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
2239 | spin_lock(&sbi->s_ext_stats_lock); | |
2240 | sbi->s_ext_blocks += ee_len; | |
2241 | sbi->s_ext_extents++; | |
2242 | if (ee_len < sbi->s_ext_min) | |
2243 | sbi->s_ext_min = ee_len; | |
2244 | if (ee_len > sbi->s_ext_max) | |
2245 | sbi->s_ext_max = ee_len; | |
2246 | if (ext_depth(inode) > sbi->s_depth_max) | |
2247 | sbi->s_depth_max = ext_depth(inode); | |
2248 | spin_unlock(&sbi->s_ext_stats_lock); | |
2249 | } | |
2250 | #endif | |
2251 | if (from >= le32_to_cpu(ex->ee_block) | |
2252 | && to == le32_to_cpu(ex->ee_block) + ee_len - 1) { | |
2253 | /* tail removal */ | |
2254 | ext4_lblk_t num; | |
2255 | ||
2256 | num = le32_to_cpu(ex->ee_block) + ee_len - from; | |
2257 | pblk = ext4_ext_pblock(ex) + ee_len - num; | |
2258 | ext_debug("free last %u blocks starting %llu\n", num, pblk); | |
2259 | ext4_free_blocks(handle, inode, NULL, pblk, num, flags); | |
2260 | /* | |
2261 | * If the block range to be freed didn't start at the | |
2262 | * beginning of a cluster, and we removed the entire | |
2263 | * extent, save the partial cluster here, since we | |
2264 | * might need to delete if we determine that the | |
2265 | * truncate operation has removed all of the blocks in | |
2266 | * the cluster. | |
2267 | */ | |
2268 | if (pblk & (sbi->s_cluster_ratio - 1) && | |
2269 | (ee_len == num)) | |
2270 | *partial_cluster = EXT4_B2C(sbi, pblk); | |
2271 | else | |
2272 | *partial_cluster = 0; | |
2273 | } else if (from == le32_to_cpu(ex->ee_block) | |
2274 | && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) { | |
2275 | /* head removal */ | |
2276 | ext4_lblk_t num; | |
2277 | ext4_fsblk_t start; | |
2278 | ||
2279 | num = to - from; | |
2280 | start = ext4_ext_pblock(ex); | |
2281 | ||
2282 | ext_debug("free first %u blocks starting %llu\n", num, start); | |
2283 | ext4_free_blocks(handle, inode, NULL, start, num, flags); | |
2284 | ||
2285 | } else { | |
2286 | printk(KERN_INFO "strange request: removal(2) " | |
2287 | "%u-%u from %u:%u\n", | |
2288 | from, to, le32_to_cpu(ex->ee_block), ee_len); | |
2289 | } | |
2290 | return 0; | |
2291 | } | |
2292 | ||
2293 | ||
2294 | /* | |
2295 | * ext4_ext_rm_leaf() Removes the extents associated with the | |
2296 | * blocks appearing between "start" and "end", and splits the extents | |
2297 | * if "start" and "end" appear in the same extent | |
2298 | * | |
2299 | * @handle: The journal handle | |
2300 | * @inode: The files inode | |
2301 | * @path: The path to the leaf | |
2302 | * @start: The first block to remove | |
2303 | * @end: The last block to remove | |
2304 | */ | |
2305 | static int | |
2306 | ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, | |
2307 | struct ext4_ext_path *path, ext4_fsblk_t *partial_cluster, | |
2308 | ext4_lblk_t start, ext4_lblk_t end) | |
2309 | { | |
2310 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
2311 | int err = 0, correct_index = 0; | |
2312 | int depth = ext_depth(inode), credits; | |
2313 | struct ext4_extent_header *eh; | |
2314 | ext4_lblk_t a, b, block; | |
2315 | unsigned num; | |
2316 | ext4_lblk_t ex_ee_block; | |
2317 | unsigned short ex_ee_len; | |
2318 | unsigned uninitialized = 0; | |
2319 | struct ext4_extent *ex; | |
2320 | struct ext4_map_blocks map; | |
2321 | ||
2322 | /* the header must be checked already in ext4_ext_remove_space() */ | |
2323 | ext_debug("truncate since %u in leaf\n", start); | |
2324 | if (!path[depth].p_hdr) | |
2325 | path[depth].p_hdr = ext_block_hdr(path[depth].p_bh); | |
2326 | eh = path[depth].p_hdr; | |
2327 | if (unlikely(path[depth].p_hdr == NULL)) { | |
2328 | EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth); | |
2329 | return -EIO; | |
2330 | } | |
2331 | /* find where to start removing */ | |
2332 | ex = EXT_LAST_EXTENT(eh); | |
2333 | ||
2334 | ex_ee_block = le32_to_cpu(ex->ee_block); | |
2335 | ex_ee_len = ext4_ext_get_actual_len(ex); | |
2336 | ||
2337 | trace_ext4_ext_rm_leaf(inode, start, ex, *partial_cluster); | |
2338 | ||
2339 | while (ex >= EXT_FIRST_EXTENT(eh) && | |
2340 | ex_ee_block + ex_ee_len > start) { | |
2341 | ||
2342 | if (ext4_ext_is_uninitialized(ex)) | |
2343 | uninitialized = 1; | |
2344 | else | |
2345 | uninitialized = 0; | |
2346 | ||
2347 | ext_debug("remove ext %u:[%d]%d\n", ex_ee_block, | |
2348 | uninitialized, ex_ee_len); | |
2349 | path[depth].p_ext = ex; | |
2350 | ||
2351 | a = ex_ee_block > start ? ex_ee_block : start; | |
2352 | b = ex_ee_block+ex_ee_len - 1 < end ? | |
2353 | ex_ee_block+ex_ee_len - 1 : end; | |
2354 | ||
2355 | ext_debug(" border %u:%u\n", a, b); | |
2356 | ||
2357 | /* If this extent is beyond the end of the hole, skip it */ | |
2358 | if (end <= ex_ee_block) { | |
2359 | ex--; | |
2360 | ex_ee_block = le32_to_cpu(ex->ee_block); | |
2361 | ex_ee_len = ext4_ext_get_actual_len(ex); | |
2362 | continue; | |
2363 | } else if (a != ex_ee_block && | |
2364 | b != ex_ee_block + ex_ee_len - 1) { | |
2365 | /* | |
2366 | * If this is a truncate, then this condition should | |
2367 | * never happen because at least one of the end points | |
2368 | * needs to be on the edge of the extent. | |
2369 | */ | |
2370 | if (end == EXT_MAX_BLOCKS - 1) { | |
2371 | ext_debug(" bad truncate %u:%u\n", | |
2372 | start, end); | |
2373 | block = 0; | |
2374 | num = 0; | |
2375 | err = -EIO; | |
2376 | goto out; | |
2377 | } | |
2378 | /* | |
2379 | * else this is a hole punch, so the extent needs to | |
2380 | * be split since neither edge of the hole is on the | |
2381 | * extent edge | |
2382 | */ | |
2383 | else{ | |
2384 | map.m_pblk = ext4_ext_pblock(ex); | |
2385 | map.m_lblk = ex_ee_block; | |
2386 | map.m_len = b - ex_ee_block; | |
2387 | ||
2388 | err = ext4_split_extent(handle, | |
2389 | inode, path, &map, 0, | |
2390 | EXT4_GET_BLOCKS_PUNCH_OUT_EXT | | |
2391 | EXT4_GET_BLOCKS_PRE_IO); | |
2392 | ||
2393 | if (err < 0) | |
2394 | goto out; | |
2395 | ||
2396 | ex_ee_len = ext4_ext_get_actual_len(ex); | |
2397 | ||
2398 | b = ex_ee_block+ex_ee_len - 1 < end ? | |
2399 | ex_ee_block+ex_ee_len - 1 : end; | |
2400 | ||
2401 | /* Then remove tail of this extent */ | |
2402 | block = ex_ee_block; | |
2403 | num = a - block; | |
2404 | } | |
2405 | } else if (a != ex_ee_block) { | |
2406 | /* remove tail of the extent */ | |
2407 | block = ex_ee_block; | |
2408 | num = a - block; | |
2409 | } else if (b != ex_ee_block + ex_ee_len - 1) { | |
2410 | /* remove head of the extent */ | |
2411 | block = b; | |
2412 | num = ex_ee_block + ex_ee_len - b; | |
2413 | ||
2414 | /* | |
2415 | * If this is a truncate, this condition | |
2416 | * should never happen | |
2417 | */ | |
2418 | if (end == EXT_MAX_BLOCKS - 1) { | |
2419 | ext_debug(" bad truncate %u:%u\n", | |
2420 | start, end); | |
2421 | err = -EIO; | |
2422 | goto out; | |
2423 | } | |
2424 | } else { | |
2425 | /* remove whole extent: excellent! */ | |
2426 | block = ex_ee_block; | |
2427 | num = 0; | |
2428 | if (a != ex_ee_block) { | |
2429 | ext_debug(" bad truncate %u:%u\n", | |
2430 | start, end); | |
2431 | err = -EIO; | |
2432 | goto out; | |
2433 | } | |
2434 | ||
2435 | if (b != ex_ee_block + ex_ee_len - 1) { | |
2436 | ext_debug(" bad truncate %u:%u\n", | |
2437 | start, end); | |
2438 | err = -EIO; | |
2439 | goto out; | |
2440 | } | |
2441 | } | |
2442 | ||
2443 | /* | |
2444 | * 3 for leaf, sb, and inode plus 2 (bmap and group | |
2445 | * descriptor) for each block group; assume two block | |
2446 | * groups plus ex_ee_len/blocks_per_block_group for | |
2447 | * the worst case | |
2448 | */ | |
2449 | credits = 7 + 2*(ex_ee_len/EXT4_BLOCKS_PER_GROUP(inode->i_sb)); | |
2450 | if (ex == EXT_FIRST_EXTENT(eh)) { | |
2451 | correct_index = 1; | |
2452 | credits += (ext_depth(inode)) + 1; | |
2453 | } | |
2454 | credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb); | |
2455 | ||
2456 | err = ext4_ext_truncate_extend_restart(handle, inode, credits); | |
2457 | if (err) | |
2458 | goto out; | |
2459 | ||
2460 | err = ext4_ext_get_access(handle, inode, path + depth); | |
2461 | if (err) | |
2462 | goto out; | |
2463 | ||
2464 | err = ext4_remove_blocks(handle, inode, ex, partial_cluster, | |
2465 | a, b); | |
2466 | if (err) | |
2467 | goto out; | |
2468 | ||
2469 | if (num == 0) { | |
2470 | /* this extent is removed; mark slot entirely unused */ | |
2471 | ext4_ext_store_pblock(ex, 0); | |
2472 | } else if (block != ex_ee_block) { | |
2473 | /* | |
2474 | * If this was a head removal, then we need to update | |
2475 | * the physical block since it is now at a different | |
2476 | * location | |
2477 | */ | |
2478 | ext4_ext_store_pblock(ex, ext4_ext_pblock(ex) + (b-a)); | |
2479 | } | |
2480 | ||
2481 | ex->ee_block = cpu_to_le32(block); | |
2482 | ex->ee_len = cpu_to_le16(num); | |
2483 | /* | |
2484 | * Do not mark uninitialized if all the blocks in the | |
2485 | * extent have been removed. | |
2486 | */ | |
2487 | if (uninitialized && num) | |
2488 | ext4_ext_mark_uninitialized(ex); | |
2489 | ||
2490 | err = ext4_ext_dirty(handle, inode, path + depth); | |
2491 | if (err) | |
2492 | goto out; | |
2493 | ||
2494 | /* | |
2495 | * If the extent was completely released, | |
2496 | * we need to remove it from the leaf | |
2497 | */ | |
2498 | if (num == 0) { | |
2499 | if (end != EXT_MAX_BLOCKS - 1) { | |
2500 | /* | |
2501 | * For hole punching, we need to scoot all the | |
2502 | * extents up when an extent is removed so that | |
2503 | * we dont have blank extents in the middle | |
2504 | */ | |
2505 | memmove(ex, ex+1, (EXT_LAST_EXTENT(eh) - ex) * | |
2506 | sizeof(struct ext4_extent)); | |
2507 | ||
2508 | /* Now get rid of the one at the end */ | |
2509 | memset(EXT_LAST_EXTENT(eh), 0, | |
2510 | sizeof(struct ext4_extent)); | |
2511 | } | |
2512 | le16_add_cpu(&eh->eh_entries, -1); | |
2513 | } else | |
2514 | *partial_cluster = 0; | |
2515 | ||
2516 | ext_debug("new extent: %u:%u:%llu\n", block, num, | |
2517 | ext4_ext_pblock(ex)); | |
2518 | ex--; | |
2519 | ex_ee_block = le32_to_cpu(ex->ee_block); | |
2520 | ex_ee_len = ext4_ext_get_actual_len(ex); | |
2521 | } | |
2522 | ||
2523 | if (correct_index && eh->eh_entries) | |
2524 | err = ext4_ext_correct_indexes(handle, inode, path); | |
2525 | ||
2526 | /* | |
2527 | * If there is still a entry in the leaf node, check to see if | |
2528 | * it references the partial cluster. This is the only place | |
2529 | * where it could; if it doesn't, we can free the cluster. | |
2530 | */ | |
2531 | if (*partial_cluster && ex >= EXT_FIRST_EXTENT(eh) && | |
2532 | (EXT4_B2C(sbi, ext4_ext_pblock(ex) + ex_ee_len - 1) != | |
2533 | *partial_cluster)) { | |
2534 | int flags = EXT4_FREE_BLOCKS_FORGET; | |
2535 | ||
2536 | if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) | |
2537 | flags |= EXT4_FREE_BLOCKS_METADATA; | |
2538 | ||
2539 | ext4_free_blocks(handle, inode, NULL, | |
2540 | EXT4_C2B(sbi, *partial_cluster), | |
2541 | sbi->s_cluster_ratio, flags); | |
2542 | *partial_cluster = 0; | |
2543 | } | |
2544 | ||
2545 | /* if this leaf is free, then we should | |
2546 | * remove it from index block above */ | |
2547 | if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL) | |
2548 | err = ext4_ext_rm_idx(handle, inode, path + depth); | |
2549 | ||
2550 | out: | |
2551 | return err; | |
2552 | } | |
2553 | ||
2554 | /* | |
2555 | * ext4_ext_more_to_rm: | |
2556 | * returns 1 if current index has to be freed (even partial) | |
2557 | */ | |
2558 | static int | |
2559 | ext4_ext_more_to_rm(struct ext4_ext_path *path) | |
2560 | { | |
2561 | BUG_ON(path->p_idx == NULL); | |
2562 | ||
2563 | if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr)) | |
2564 | return 0; | |
2565 | ||
2566 | /* | |
2567 | * if truncate on deeper level happened, it wasn't partial, | |
2568 | * so we have to consider current index for truncation | |
2569 | */ | |
2570 | if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block) | |
2571 | return 0; | |
2572 | return 1; | |
2573 | } | |
2574 | ||
2575 | static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start) | |
2576 | { | |
2577 | struct super_block *sb = inode->i_sb; | |
2578 | int depth = ext_depth(inode); | |
2579 | struct ext4_ext_path *path; | |
2580 | ext4_fsblk_t partial_cluster = 0; | |
2581 | handle_t *handle; | |
2582 | int i, err; | |
2583 | ||
2584 | ext_debug("truncate since %u\n", start); | |
2585 | ||
2586 | /* probably first extent we're gonna free will be last in block */ | |
2587 | handle = ext4_journal_start(inode, depth + 1); | |
2588 | if (IS_ERR(handle)) | |
2589 | return PTR_ERR(handle); | |
2590 | ||
2591 | again: | |
2592 | ext4_ext_invalidate_cache(inode); | |
2593 | ||
2594 | trace_ext4_ext_remove_space(inode, start, depth); | |
2595 | ||
2596 | /* | |
2597 | * We start scanning from right side, freeing all the blocks | |
2598 | * after i_size and walking into the tree depth-wise. | |
2599 | */ | |
2600 | depth = ext_depth(inode); | |
2601 | path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_NOFS); | |
2602 | if (path == NULL) { | |
2603 | ext4_journal_stop(handle); | |
2604 | return -ENOMEM; | |
2605 | } | |
2606 | path[0].p_depth = depth; | |
2607 | path[0].p_hdr = ext_inode_hdr(inode); | |
2608 | if (ext4_ext_check(inode, path[0].p_hdr, depth)) { | |
2609 | err = -EIO; | |
2610 | goto out; | |
2611 | } | |
2612 | i = err = 0; | |
2613 | ||
2614 | while (i >= 0 && err == 0) { | |
2615 | if (i == depth) { | |
2616 | /* this is leaf block */ | |
2617 | err = ext4_ext_rm_leaf(handle, inode, path, | |
2618 | &partial_cluster, start, | |
2619 | EXT_MAX_BLOCKS - 1); | |
2620 | /* root level has p_bh == NULL, brelse() eats this */ | |
2621 | brelse(path[i].p_bh); | |
2622 | path[i].p_bh = NULL; | |
2623 | i--; | |
2624 | continue; | |
2625 | } | |
2626 | ||
2627 | /* this is index block */ | |
2628 | if (!path[i].p_hdr) { | |
2629 | ext_debug("initialize header\n"); | |
2630 | path[i].p_hdr = ext_block_hdr(path[i].p_bh); | |
2631 | } | |
2632 | ||
2633 | if (!path[i].p_idx) { | |
2634 | /* this level hasn't been touched yet */ | |
2635 | path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr); | |
2636 | path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1; | |
2637 | ext_debug("init index ptr: hdr 0x%p, num %d\n", | |
2638 | path[i].p_hdr, | |
2639 | le16_to_cpu(path[i].p_hdr->eh_entries)); | |
2640 | } else { | |
2641 | /* we were already here, see at next index */ | |
2642 | path[i].p_idx--; | |
2643 | } | |
2644 | ||
2645 | ext_debug("level %d - index, first 0x%p, cur 0x%p\n", | |
2646 | i, EXT_FIRST_INDEX(path[i].p_hdr), | |
2647 | path[i].p_idx); | |
2648 | if (ext4_ext_more_to_rm(path + i)) { | |
2649 | struct buffer_head *bh; | |
2650 | /* go to the next level */ | |
2651 | ext_debug("move to level %d (block %llu)\n", | |
2652 | i + 1, ext4_idx_pblock(path[i].p_idx)); | |
2653 | memset(path + i + 1, 0, sizeof(*path)); | |
2654 | bh = sb_bread(sb, ext4_idx_pblock(path[i].p_idx)); | |
2655 | if (!bh) { | |
2656 | /* should we reset i_size? */ | |
2657 | err = -EIO; | |
2658 | break; | |
2659 | } | |
2660 | if (WARN_ON(i + 1 > depth)) { | |
2661 | err = -EIO; | |
2662 | break; | |
2663 | } | |
2664 | if (ext4_ext_check(inode, ext_block_hdr(bh), | |
2665 | depth - i - 1)) { | |
2666 | err = -EIO; | |
2667 | break; | |
2668 | } | |
2669 | path[i + 1].p_bh = bh; | |
2670 | ||
2671 | /* save actual number of indexes since this | |
2672 | * number is changed at the next iteration */ | |
2673 | path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries); | |
2674 | i++; | |
2675 | } else { | |
2676 | /* we finished processing this index, go up */ | |
2677 | if (path[i].p_hdr->eh_entries == 0 && i > 0) { | |
2678 | /* index is empty, remove it; | |
2679 | * handle must be already prepared by the | |
2680 | * truncatei_leaf() */ | |
2681 | err = ext4_ext_rm_idx(handle, inode, path + i); | |
2682 | } | |
2683 | /* root level has p_bh == NULL, brelse() eats this */ | |
2684 | brelse(path[i].p_bh); | |
2685 | path[i].p_bh = NULL; | |
2686 | i--; | |
2687 | ext_debug("return to level %d\n", i); | |
2688 | } | |
2689 | } | |
2690 | ||
2691 | trace_ext4_ext_remove_space_done(inode, start, depth, partial_cluster, | |
2692 | path->p_hdr->eh_entries); | |
2693 | ||
2694 | /* If we still have something in the partial cluster and we have removed | |
2695 | * even the first extent, then we should free the blocks in the partial | |
2696 | * cluster as well. */ | |
2697 | if (partial_cluster && path->p_hdr->eh_entries == 0) { | |
2698 | int flags = EXT4_FREE_BLOCKS_FORGET; | |
2699 | ||
2700 | if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) | |
2701 | flags |= EXT4_FREE_BLOCKS_METADATA; | |
2702 | ||
2703 | ext4_free_blocks(handle, inode, NULL, | |
2704 | EXT4_C2B(EXT4_SB(sb), partial_cluster), | |
2705 | EXT4_SB(sb)->s_cluster_ratio, flags); | |
2706 | partial_cluster = 0; | |
2707 | } | |
2708 | ||
2709 | /* TODO: flexible tree reduction should be here */ | |
2710 | if (path->p_hdr->eh_entries == 0) { | |
2711 | /* | |
2712 | * truncate to zero freed all the tree, | |
2713 | * so we need to correct eh_depth | |
2714 | */ | |
2715 | err = ext4_ext_get_access(handle, inode, path); | |
2716 | if (err == 0) { | |
2717 | ext_inode_hdr(inode)->eh_depth = 0; | |
2718 | ext_inode_hdr(inode)->eh_max = | |
2719 | cpu_to_le16(ext4_ext_space_root(inode, 0)); | |
2720 | err = ext4_ext_dirty(handle, inode, path); | |
2721 | } | |
2722 | } | |
2723 | out: | |
2724 | ext4_ext_drop_refs(path); | |
2725 | kfree(path); | |
2726 | if (err == -EAGAIN) | |
2727 | goto again; | |
2728 | ext4_journal_stop(handle); | |
2729 | ||
2730 | return err; | |
2731 | } | |
2732 | ||
2733 | /* | |
2734 | * called at mount time | |
2735 | */ | |
2736 | void ext4_ext_init(struct super_block *sb) | |
2737 | { | |
2738 | /* | |
2739 | * possible initialization would be here | |
2740 | */ | |
2741 | ||
2742 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) { | |
2743 | #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS) | |
2744 | printk(KERN_INFO "EXT4-fs: file extents enabled"); | |
2745 | #ifdef AGGRESSIVE_TEST | |
2746 | printk(", aggressive tests"); | |
2747 | #endif | |
2748 | #ifdef CHECK_BINSEARCH | |
2749 | printk(", check binsearch"); | |
2750 | #endif | |
2751 | #ifdef EXTENTS_STATS | |
2752 | printk(", stats"); | |
2753 | #endif | |
2754 | printk("\n"); | |
2755 | #endif | |
2756 | #ifdef EXTENTS_STATS | |
2757 | spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock); | |
2758 | EXT4_SB(sb)->s_ext_min = 1 << 30; | |
2759 | EXT4_SB(sb)->s_ext_max = 0; | |
2760 | #endif | |
2761 | } | |
2762 | } | |
2763 | ||
2764 | /* | |
2765 | * called at umount time | |
2766 | */ | |
2767 | void ext4_ext_release(struct super_block *sb) | |
2768 | { | |
2769 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) | |
2770 | return; | |
2771 | ||
2772 | #ifdef EXTENTS_STATS | |
2773 | if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) { | |
2774 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2775 | printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n", | |
2776 | sbi->s_ext_blocks, sbi->s_ext_extents, | |
2777 | sbi->s_ext_blocks / sbi->s_ext_extents); | |
2778 | printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n", | |
2779 | sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max); | |
2780 | } | |
2781 | #endif | |
2782 | } | |
2783 | ||
2784 | /* FIXME!! we need to try to merge to left or right after zero-out */ | |
2785 | static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex) | |
2786 | { | |
2787 | ext4_fsblk_t ee_pblock; | |
2788 | unsigned int ee_len; | |
2789 | int ret; | |
2790 | ||
2791 | ee_len = ext4_ext_get_actual_len(ex); | |
2792 | ee_pblock = ext4_ext_pblock(ex); | |
2793 | ||
2794 | ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS); | |
2795 | if (ret > 0) | |
2796 | ret = 0; | |
2797 | ||
2798 | return ret; | |
2799 | } | |
2800 | ||
2801 | /* | |
2802 | * used by extent splitting. | |
2803 | */ | |
2804 | #define EXT4_EXT_MAY_ZEROOUT 0x1 /* safe to zeroout if split fails \ | |
2805 | due to ENOSPC */ | |
2806 | #define EXT4_EXT_MARK_UNINIT1 0x2 /* mark first half uninitialized */ | |
2807 | #define EXT4_EXT_MARK_UNINIT2 0x4 /* mark second half uninitialized */ | |
2808 | ||
2809 | /* | |
2810 | * ext4_split_extent_at() splits an extent at given block. | |
2811 | * | |
2812 | * @handle: the journal handle | |
2813 | * @inode: the file inode | |
2814 | * @path: the path to the extent | |
2815 | * @split: the logical block where the extent is splitted. | |
2816 | * @split_flags: indicates if the extent could be zeroout if split fails, and | |
2817 | * the states(init or uninit) of new extents. | |
2818 | * @flags: flags used to insert new extent to extent tree. | |
2819 | * | |
2820 | * | |
2821 | * Splits extent [a, b] into two extents [a, @split) and [@split, b], states | |
2822 | * of which are deterimined by split_flag. | |
2823 | * | |
2824 | * There are two cases: | |
2825 | * a> the extent are splitted into two extent. | |
2826 | * b> split is not needed, and just mark the extent. | |
2827 | * | |
2828 | * return 0 on success. | |
2829 | */ | |
2830 | static int ext4_split_extent_at(handle_t *handle, | |
2831 | struct inode *inode, | |
2832 | struct ext4_ext_path *path, | |
2833 | ext4_lblk_t split, | |
2834 | int split_flag, | |
2835 | int flags) | |
2836 | { | |
2837 | ext4_fsblk_t newblock; | |
2838 | ext4_lblk_t ee_block; | |
2839 | struct ext4_extent *ex, newex, orig_ex; | |
2840 | struct ext4_extent *ex2 = NULL; | |
2841 | unsigned int ee_len, depth; | |
2842 | int err = 0; | |
2843 | ||
2844 | ext_debug("ext4_split_extents_at: inode %lu, logical" | |
2845 | "block %llu\n", inode->i_ino, (unsigned long long)split); | |
2846 | ||
2847 | ext4_ext_show_leaf(inode, path); | |
2848 | ||
2849 | depth = ext_depth(inode); | |
2850 | ex = path[depth].p_ext; | |
2851 | ee_block = le32_to_cpu(ex->ee_block); | |
2852 | ee_len = ext4_ext_get_actual_len(ex); | |
2853 | newblock = split - ee_block + ext4_ext_pblock(ex); | |
2854 | ||
2855 | BUG_ON(split < ee_block || split >= (ee_block + ee_len)); | |
2856 | ||
2857 | err = ext4_ext_get_access(handle, inode, path + depth); | |
2858 | if (err) | |
2859 | goto out; | |
2860 | ||
2861 | if (split == ee_block) { | |
2862 | /* | |
2863 | * case b: block @split is the block that the extent begins with | |
2864 | * then we just change the state of the extent, and splitting | |
2865 | * is not needed. | |
2866 | */ | |
2867 | if (split_flag & EXT4_EXT_MARK_UNINIT2) | |
2868 | ext4_ext_mark_uninitialized(ex); | |
2869 | else | |
2870 | ext4_ext_mark_initialized(ex); | |
2871 | ||
2872 | if (!(flags & EXT4_GET_BLOCKS_PRE_IO)) | |
2873 | ext4_ext_try_to_merge(inode, path, ex); | |
2874 | ||
2875 | err = ext4_ext_dirty(handle, inode, path + depth); | |
2876 | goto out; | |
2877 | } | |
2878 | ||
2879 | /* case a */ | |
2880 | memcpy(&orig_ex, ex, sizeof(orig_ex)); | |
2881 | ex->ee_len = cpu_to_le16(split - ee_block); | |
2882 | if (split_flag & EXT4_EXT_MARK_UNINIT1) | |
2883 | ext4_ext_mark_uninitialized(ex); | |
2884 | ||
2885 | /* | |
2886 | * path may lead to new leaf, not to original leaf any more | |
2887 | * after ext4_ext_insert_extent() returns, | |
2888 | */ | |
2889 | err = ext4_ext_dirty(handle, inode, path + depth); | |
2890 | if (err) | |
2891 | goto fix_extent_len; | |
2892 | ||
2893 | ex2 = &newex; | |
2894 | ex2->ee_block = cpu_to_le32(split); | |
2895 | ex2->ee_len = cpu_to_le16(ee_len - (split - ee_block)); | |
2896 | ext4_ext_store_pblock(ex2, newblock); | |
2897 | if (split_flag & EXT4_EXT_MARK_UNINIT2) | |
2898 | ext4_ext_mark_uninitialized(ex2); | |
2899 | ||
2900 | err = ext4_ext_insert_extent(handle, inode, path, &newex, flags); | |
2901 | if (err == -ENOSPC && (EXT4_EXT_MAY_ZEROOUT & split_flag)) { | |
2902 | err = ext4_ext_zeroout(inode, &orig_ex); | |
2903 | if (err) | |
2904 | goto fix_extent_len; | |
2905 | /* update the extent length and mark as initialized */ | |
2906 | ex->ee_len = cpu_to_le32(ee_len); | |
2907 | ext4_ext_try_to_merge(inode, path, ex); | |
2908 | err = ext4_ext_dirty(handle, inode, path + depth); | |
2909 | goto out; | |
2910 | } else if (err) | |
2911 | goto fix_extent_len; | |
2912 | ||
2913 | out: | |
2914 | ext4_ext_show_leaf(inode, path); | |
2915 | return err; | |
2916 | ||
2917 | fix_extent_len: | |
2918 | ex->ee_len = orig_ex.ee_len; | |
2919 | ext4_ext_dirty(handle, inode, path + depth); | |
2920 | return err; | |
2921 | } | |
2922 | ||
2923 | /* | |
2924 | * ext4_split_extents() splits an extent and mark extent which is covered | |
2925 | * by @map as split_flags indicates | |
2926 | * | |
2927 | * It may result in splitting the extent into multiple extents (upto three) | |
2928 | * There are three possibilities: | |
2929 | * a> There is no split required | |
2930 | * b> Splits in two extents: Split is happening at either end of the extent | |
2931 | * c> Splits in three extents: Somone is splitting in middle of the extent | |
2932 | * | |
2933 | */ | |
2934 | static int ext4_split_extent(handle_t *handle, | |
2935 | struct inode *inode, | |
2936 | struct ext4_ext_path *path, | |
2937 | struct ext4_map_blocks *map, | |
2938 | int split_flag, | |
2939 | int flags) | |
2940 | { | |
2941 | ext4_lblk_t ee_block; | |
2942 | struct ext4_extent *ex; | |
2943 | unsigned int ee_len, depth; | |
2944 | int err = 0; | |
2945 | int uninitialized; | |
2946 | int split_flag1, flags1; | |
2947 | ||
2948 | depth = ext_depth(inode); | |
2949 | ex = path[depth].p_ext; | |
2950 | ee_block = le32_to_cpu(ex->ee_block); | |
2951 | ee_len = ext4_ext_get_actual_len(ex); | |
2952 | uninitialized = ext4_ext_is_uninitialized(ex); | |
2953 | ||
2954 | if (map->m_lblk + map->m_len < ee_block + ee_len) { | |
2955 | split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT ? | |
2956 | EXT4_EXT_MAY_ZEROOUT : 0; | |
2957 | flags1 = flags | EXT4_GET_BLOCKS_PRE_IO; | |
2958 | if (uninitialized) | |
2959 | split_flag1 |= EXT4_EXT_MARK_UNINIT1 | | |
2960 | EXT4_EXT_MARK_UNINIT2; | |
2961 | err = ext4_split_extent_at(handle, inode, path, | |
2962 | map->m_lblk + map->m_len, split_flag1, flags1); | |
2963 | if (err) | |
2964 | goto out; | |
2965 | } | |
2966 | ||
2967 | ext4_ext_drop_refs(path); | |
2968 | path = ext4_ext_find_extent(inode, map->m_lblk, path); | |
2969 | if (IS_ERR(path)) | |
2970 | return PTR_ERR(path); | |
2971 | ||
2972 | if (map->m_lblk >= ee_block) { | |
2973 | split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT ? | |
2974 | EXT4_EXT_MAY_ZEROOUT : 0; | |
2975 | if (uninitialized) | |
2976 | split_flag1 |= EXT4_EXT_MARK_UNINIT1; | |
2977 | if (split_flag & EXT4_EXT_MARK_UNINIT2) | |
2978 | split_flag1 |= EXT4_EXT_MARK_UNINIT2; | |
2979 | err = ext4_split_extent_at(handle, inode, path, | |
2980 | map->m_lblk, split_flag1, flags); | |
2981 | if (err) | |
2982 | goto out; | |
2983 | } | |
2984 | ||
2985 | ext4_ext_show_leaf(inode, path); | |
2986 | out: | |
2987 | return err ? err : map->m_len; | |
2988 | } | |
2989 | ||
2990 | #define EXT4_EXT_ZERO_LEN 7 | |
2991 | /* | |
2992 | * This function is called by ext4_ext_map_blocks() if someone tries to write | |
2993 | * to an uninitialized extent. It may result in splitting the uninitialized | |
2994 | * extent into multiple extents (up to three - one initialized and two | |
2995 | * uninitialized). | |
2996 | * There are three possibilities: | |
2997 | * a> There is no split required: Entire extent should be initialized | |
2998 | * b> Splits in two extents: Write is happening at either end of the extent | |
2999 | * c> Splits in three extents: Somone is writing in middle of the extent | |
3000 | */ | |
3001 | static int ext4_ext_convert_to_initialized(handle_t *handle, | |
3002 | struct inode *inode, | |
3003 | struct ext4_map_blocks *map, | |
3004 | struct ext4_ext_path *path) | |
3005 | { | |
3006 | struct ext4_map_blocks split_map; | |
3007 | struct ext4_extent zero_ex; | |
3008 | struct ext4_extent *ex; | |
3009 | ext4_lblk_t ee_block, eof_block; | |
3010 | unsigned int allocated, ee_len, depth; | |
3011 | int err = 0; | |
3012 | int split_flag = 0; | |
3013 | ||
3014 | ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical" | |
3015 | "block %llu, max_blocks %u\n", inode->i_ino, | |
3016 | (unsigned long long)map->m_lblk, map->m_len); | |
3017 | ||
3018 | eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >> | |
3019 | inode->i_sb->s_blocksize_bits; | |
3020 | if (eof_block < map->m_lblk + map->m_len) | |
3021 | eof_block = map->m_lblk + map->m_len; | |
3022 | ||
3023 | depth = ext_depth(inode); | |
3024 | ex = path[depth].p_ext; | |
3025 | ee_block = le32_to_cpu(ex->ee_block); | |
3026 | ee_len = ext4_ext_get_actual_len(ex); | |
3027 | allocated = ee_len - (map->m_lblk - ee_block); | |
3028 | ||
3029 | WARN_ON(map->m_lblk < ee_block); | |
3030 | /* | |
3031 | * It is safe to convert extent to initialized via explicit | |
3032 | * zeroout only if extent is fully insde i_size or new_size. | |
3033 | */ | |
3034 | split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0; | |
3035 | ||
3036 | /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */ | |
3037 | if (ee_len <= 2*EXT4_EXT_ZERO_LEN && | |
3038 | (EXT4_EXT_MAY_ZEROOUT & split_flag)) { | |
3039 | err = ext4_ext_zeroout(inode, ex); | |
3040 | if (err) | |
3041 | goto out; | |
3042 | ||
3043 | err = ext4_ext_get_access(handle, inode, path + depth); | |
3044 | if (err) | |
3045 | goto out; | |
3046 | ext4_ext_mark_initialized(ex); | |
3047 | ext4_ext_try_to_merge(inode, path, ex); | |
3048 | err = ext4_ext_dirty(handle, inode, path + depth); | |
3049 | goto out; | |
3050 | } | |
3051 | ||
3052 | /* | |
3053 | * four cases: | |
3054 | * 1. split the extent into three extents. | |
3055 | * 2. split the extent into two extents, zeroout the first half. | |
3056 | * 3. split the extent into two extents, zeroout the second half. | |
3057 | * 4. split the extent into two extents with out zeroout. | |
3058 | */ | |
3059 | split_map.m_lblk = map->m_lblk; | |
3060 | split_map.m_len = map->m_len; | |
3061 | ||
3062 | if (allocated > map->m_len) { | |
3063 | if (allocated <= EXT4_EXT_ZERO_LEN && | |
3064 | (EXT4_EXT_MAY_ZEROOUT & split_flag)) { | |
3065 | /* case 3 */ | |
3066 | zero_ex.ee_block = | |
3067 | cpu_to_le32(map->m_lblk); | |
3068 | zero_ex.ee_len = cpu_to_le16(allocated); | |
3069 | ext4_ext_store_pblock(&zero_ex, | |
3070 | ext4_ext_pblock(ex) + map->m_lblk - ee_block); | |
3071 | err = ext4_ext_zeroout(inode, &zero_ex); | |
3072 | if (err) | |
3073 | goto out; | |
3074 | split_map.m_lblk = map->m_lblk; | |
3075 | split_map.m_len = allocated; | |
3076 | } else if ((map->m_lblk - ee_block + map->m_len < | |
3077 | EXT4_EXT_ZERO_LEN) && | |
3078 | (EXT4_EXT_MAY_ZEROOUT & split_flag)) { | |
3079 | /* case 2 */ | |
3080 | if (map->m_lblk != ee_block) { | |
3081 | zero_ex.ee_block = ex->ee_block; | |
3082 | zero_ex.ee_len = cpu_to_le16(map->m_lblk - | |
3083 | ee_block); | |
3084 | ext4_ext_store_pblock(&zero_ex, | |
3085 | ext4_ext_pblock(ex)); | |
3086 | err = ext4_ext_zeroout(inode, &zero_ex); | |
3087 | if (err) | |
3088 | goto out; | |
3089 | } | |
3090 | ||
3091 | split_map.m_lblk = ee_block; | |
3092 | split_map.m_len = map->m_lblk - ee_block + map->m_len; | |
3093 | allocated = map->m_len; | |
3094 | } | |
3095 | } | |
3096 | ||
3097 | allocated = ext4_split_extent(handle, inode, path, | |
3098 | &split_map, split_flag, 0); | |
3099 | if (allocated < 0) | |
3100 | err = allocated; | |
3101 | ||
3102 | out: | |
3103 | return err ? err : allocated; | |
3104 | } | |
3105 | ||
3106 | /* | |
3107 | * This function is called by ext4_ext_map_blocks() from | |
3108 | * ext4_get_blocks_dio_write() when DIO to write | |
3109 | * to an uninitialized extent. | |
3110 | * | |
3111 | * Writing to an uninitialized extent may result in splitting the uninitialized | |
3112 | * extent into multiple /initialized uninitialized extents (up to three) | |
3113 | * There are three possibilities: | |
3114 | * a> There is no split required: Entire extent should be uninitialized | |
3115 | * b> Splits in two extents: Write is happening at either end of the extent | |
3116 | * c> Splits in three extents: Somone is writing in middle of the extent | |
3117 | * | |
3118 | * One of more index blocks maybe needed if the extent tree grow after | |
3119 | * the uninitialized extent split. To prevent ENOSPC occur at the IO | |
3120 | * complete, we need to split the uninitialized extent before DIO submit | |
3121 | * the IO. The uninitialized extent called at this time will be split | |
3122 | * into three uninitialized extent(at most). After IO complete, the part | |
3123 | * being filled will be convert to initialized by the end_io callback function | |
3124 | * via ext4_convert_unwritten_extents(). | |
3125 | * | |
3126 | * Returns the size of uninitialized extent to be written on success. | |
3127 | */ | |
3128 | static int ext4_split_unwritten_extents(handle_t *handle, | |
3129 | struct inode *inode, | |
3130 | struct ext4_map_blocks *map, | |
3131 | struct ext4_ext_path *path, | |
3132 | int flags) | |
3133 | { | |
3134 | ext4_lblk_t eof_block; | |
3135 | ext4_lblk_t ee_block; | |
3136 | struct ext4_extent *ex; | |
3137 | unsigned int ee_len; | |
3138 | int split_flag = 0, depth; | |
3139 | ||
3140 | ext_debug("ext4_split_unwritten_extents: inode %lu, logical" | |
3141 | "block %llu, max_blocks %u\n", inode->i_ino, | |
3142 | (unsigned long long)map->m_lblk, map->m_len); | |
3143 | ||
3144 | eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >> | |
3145 | inode->i_sb->s_blocksize_bits; | |
3146 | if (eof_block < map->m_lblk + map->m_len) | |
3147 | eof_block = map->m_lblk + map->m_len; | |
3148 | /* | |
3149 | * It is safe to convert extent to initialized via explicit | |
3150 | * zeroout only if extent is fully insde i_size or new_size. | |
3151 | */ | |
3152 | depth = ext_depth(inode); | |
3153 | ex = path[depth].p_ext; | |
3154 | ee_block = le32_to_cpu(ex->ee_block); | |
3155 | ee_len = ext4_ext_get_actual_len(ex); | |
3156 | ||
3157 | split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0; | |
3158 | split_flag |= EXT4_EXT_MARK_UNINIT2; | |
3159 | ||
3160 | flags |= EXT4_GET_BLOCKS_PRE_IO; | |
3161 | return ext4_split_extent(handle, inode, path, map, split_flag, flags); | |
3162 | } | |
3163 | ||
3164 | static int ext4_convert_unwritten_extents_endio(handle_t *handle, | |
3165 | struct inode *inode, | |
3166 | struct ext4_ext_path *path) | |
3167 | { | |
3168 | struct ext4_extent *ex; | |
3169 | int depth; | |
3170 | int err = 0; | |
3171 | ||
3172 | depth = ext_depth(inode); | |
3173 | ex = path[depth].p_ext; | |
3174 | ||
3175 | ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical" | |
3176 | "block %llu, max_blocks %u\n", inode->i_ino, | |
3177 | (unsigned long long)le32_to_cpu(ex->ee_block), | |
3178 | ext4_ext_get_actual_len(ex)); | |
3179 | ||
3180 | err = ext4_ext_get_access(handle, inode, path + depth); | |
3181 | if (err) | |
3182 | goto out; | |
3183 | /* first mark the extent as initialized */ | |
3184 | ext4_ext_mark_initialized(ex); | |
3185 | ||
3186 | /* note: ext4_ext_correct_indexes() isn't needed here because | |
3187 | * borders are not changed | |
3188 | */ | |
3189 | ext4_ext_try_to_merge(inode, path, ex); | |
3190 | ||
3191 | /* Mark modified extent as dirty */ | |
3192 | err = ext4_ext_dirty(handle, inode, path + depth); | |
3193 | out: | |
3194 | ext4_ext_show_leaf(inode, path); | |
3195 | return err; | |
3196 | } | |
3197 | ||
3198 | static void unmap_underlying_metadata_blocks(struct block_device *bdev, | |
3199 | sector_t block, int count) | |
3200 | { | |
3201 | int i; | |
3202 | for (i = 0; i < count; i++) | |
3203 | unmap_underlying_metadata(bdev, block + i); | |
3204 | } | |
3205 | ||
3206 | /* | |
3207 | * Handle EOFBLOCKS_FL flag, clearing it if necessary | |
3208 | */ | |
3209 | static int check_eofblocks_fl(handle_t *handle, struct inode *inode, | |
3210 | ext4_lblk_t lblk, | |
3211 | struct ext4_ext_path *path, | |
3212 | unsigned int len) | |
3213 | { | |
3214 | int i, depth; | |
3215 | struct ext4_extent_header *eh; | |
3216 | struct ext4_extent *last_ex; | |
3217 | ||
3218 | if (!ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS)) | |
3219 | return 0; | |
3220 | ||
3221 | depth = ext_depth(inode); | |
3222 | eh = path[depth].p_hdr; | |
3223 | ||
3224 | if (unlikely(!eh->eh_entries)) { | |
3225 | EXT4_ERROR_INODE(inode, "eh->eh_entries == 0 and " | |
3226 | "EOFBLOCKS_FL set"); | |
3227 | return -EIO; | |
3228 | } | |
3229 | last_ex = EXT_LAST_EXTENT(eh); | |
3230 | /* | |
3231 | * We should clear the EOFBLOCKS_FL flag if we are writing the | |
3232 | * last block in the last extent in the file. We test this by | |
3233 | * first checking to see if the caller to | |
3234 | * ext4_ext_get_blocks() was interested in the last block (or | |
3235 | * a block beyond the last block) in the current extent. If | |
3236 | * this turns out to be false, we can bail out from this | |
3237 | * function immediately. | |
3238 | */ | |
3239 | if (lblk + len < le32_to_cpu(last_ex->ee_block) + | |
3240 | ext4_ext_get_actual_len(last_ex)) | |
3241 | return 0; | |
3242 | /* | |
3243 | * If the caller does appear to be planning to write at or | |
3244 | * beyond the end of the current extent, we then test to see | |
3245 | * if the current extent is the last extent in the file, by | |
3246 | * checking to make sure it was reached via the rightmost node | |
3247 | * at each level of the tree. | |
3248 | */ | |
3249 | for (i = depth-1; i >= 0; i--) | |
3250 | if (path[i].p_idx != EXT_LAST_INDEX(path[i].p_hdr)) | |
3251 | return 0; | |
3252 | ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS); | |
3253 | return ext4_mark_inode_dirty(handle, inode); | |
3254 | } | |
3255 | ||
3256 | /** | |
3257 | * ext4_find_delalloc_range: find delayed allocated block in the given range. | |
3258 | * | |
3259 | * Goes through the buffer heads in the range [lblk_start, lblk_end] and returns | |
3260 | * whether there are any buffers marked for delayed allocation. It returns '1' | |
3261 | * on the first delalloc'ed buffer head found. If no buffer head in the given | |
3262 | * range is marked for delalloc, it returns 0. | |
3263 | * lblk_start should always be <= lblk_end. | |
3264 | * search_hint_reverse is to indicate that searching in reverse from lblk_end to | |
3265 | * lblk_start might be more efficient (i.e., we will likely hit the delalloc'ed | |
3266 | * block sooner). This is useful when blocks are truncated sequentially from | |
3267 | * lblk_start towards lblk_end. | |
3268 | */ | |
3269 | static int ext4_find_delalloc_range(struct inode *inode, | |
3270 | ext4_lblk_t lblk_start, | |
3271 | ext4_lblk_t lblk_end, | |
3272 | int search_hint_reverse) | |
3273 | { | |
3274 | struct address_space *mapping = inode->i_mapping; | |
3275 | struct buffer_head *head, *bh = NULL; | |
3276 | struct page *page; | |
3277 | ext4_lblk_t i, pg_lblk; | |
3278 | pgoff_t index; | |
3279 | ||
3280 | /* reverse search wont work if fs block size is less than page size */ | |
3281 | if (inode->i_blkbits < PAGE_CACHE_SHIFT) | |
3282 | search_hint_reverse = 0; | |
3283 | ||
3284 | if (search_hint_reverse) | |
3285 | i = lblk_end; | |
3286 | else | |
3287 | i = lblk_start; | |
3288 | ||
3289 | index = i >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
3290 | ||
3291 | while ((i >= lblk_start) && (i <= lblk_end)) { | |
3292 | page = find_get_page(mapping, index); | |
3293 | if (!page) | |
3294 | goto nextpage; | |
3295 | ||
3296 | if (!page_has_buffers(page)) | |
3297 | goto nextpage; | |
3298 | ||
3299 | head = page_buffers(page); | |
3300 | if (!head) | |
3301 | goto nextpage; | |
3302 | ||
3303 | bh = head; | |
3304 | pg_lblk = index << (PAGE_CACHE_SHIFT - | |
3305 | inode->i_blkbits); | |
3306 | do { | |
3307 | if (unlikely(pg_lblk < lblk_start)) { | |
3308 | /* | |
3309 | * This is possible when fs block size is less | |
3310 | * than page size and our cluster starts/ends in | |
3311 | * middle of the page. So we need to skip the | |
3312 | * initial few blocks till we reach the 'lblk' | |
3313 | */ | |
3314 | pg_lblk++; | |
3315 | continue; | |
3316 | } | |
3317 | ||
3318 | /* Check if the buffer is delayed allocated and that it | |
3319 | * is not yet mapped. (when da-buffers are mapped during | |
3320 | * their writeout, their da_mapped bit is set.) | |
3321 | */ | |
3322 | if (buffer_delay(bh) && !buffer_da_mapped(bh)) { | |
3323 | page_cache_release(page); | |
3324 | trace_ext4_find_delalloc_range(inode, | |
3325 | lblk_start, lblk_end, | |
3326 | search_hint_reverse, | |
3327 | 1, i); | |
3328 | return 1; | |
3329 | } | |
3330 | if (search_hint_reverse) | |
3331 | i--; | |
3332 | else | |
3333 | i++; | |
3334 | } while ((i >= lblk_start) && (i <= lblk_end) && | |
3335 | ((bh = bh->b_this_page) != head)); | |
3336 | nextpage: | |
3337 | if (page) | |
3338 | page_cache_release(page); | |
3339 | /* | |
3340 | * Move to next page. 'i' will be the first lblk in the next | |
3341 | * page. | |
3342 | */ | |
3343 | if (search_hint_reverse) | |
3344 | index--; | |
3345 | else | |
3346 | index++; | |
3347 | i = index << (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
3348 | } | |
3349 | ||
3350 | trace_ext4_find_delalloc_range(inode, lblk_start, lblk_end, | |
3351 | search_hint_reverse, 0, 0); | |
3352 | return 0; | |
3353 | } | |
3354 | ||
3355 | int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk, | |
3356 | int search_hint_reverse) | |
3357 | { | |
3358 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
3359 | ext4_lblk_t lblk_start, lblk_end; | |
3360 | lblk_start = lblk & (~(sbi->s_cluster_ratio - 1)); | |
3361 | lblk_end = lblk_start + sbi->s_cluster_ratio - 1; | |
3362 | ||
3363 | return ext4_find_delalloc_range(inode, lblk_start, lblk_end, | |
3364 | search_hint_reverse); | |
3365 | } | |
3366 | ||
3367 | /** | |
3368 | * Determines how many complete clusters (out of those specified by the 'map') | |
3369 | * are under delalloc and were reserved quota for. | |
3370 | * This function is called when we are writing out the blocks that were | |
3371 | * originally written with their allocation delayed, but then the space was | |
3372 | * allocated using fallocate() before the delayed allocation could be resolved. | |
3373 | * The cases to look for are: | |
3374 | * ('=' indicated delayed allocated blocks | |
3375 | * '-' indicates non-delayed allocated blocks) | |
3376 | * (a) partial clusters towards beginning and/or end outside of allocated range | |
3377 | * are not delalloc'ed. | |
3378 | * Ex: | |
3379 | * |----c---=|====c====|====c====|===-c----| | |
3380 | * |++++++ allocated ++++++| | |
3381 | * ==> 4 complete clusters in above example | |
3382 | * | |
3383 | * (b) partial cluster (outside of allocated range) towards either end is | |
3384 | * marked for delayed allocation. In this case, we will exclude that | |
3385 | * cluster. | |
3386 | * Ex: | |
3387 | * |----====c========|========c========| | |
3388 | * |++++++ allocated ++++++| | |
3389 | * ==> 1 complete clusters in above example | |
3390 | * | |
3391 | * Ex: | |
3392 | * |================c================| | |
3393 | * |++++++ allocated ++++++| | |
3394 | * ==> 0 complete clusters in above example | |
3395 | * | |
3396 | * The ext4_da_update_reserve_space will be called only if we | |
3397 | * determine here that there were some "entire" clusters that span | |
3398 | * this 'allocated' range. | |
3399 | * In the non-bigalloc case, this function will just end up returning num_blks | |
3400 | * without ever calling ext4_find_delalloc_range. | |
3401 | */ | |
3402 | static unsigned int | |
3403 | get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start, | |
3404 | unsigned int num_blks) | |
3405 | { | |
3406 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
3407 | ext4_lblk_t alloc_cluster_start, alloc_cluster_end; | |
3408 | ext4_lblk_t lblk_from, lblk_to, c_offset; | |
3409 | unsigned int allocated_clusters = 0; | |
3410 | ||
3411 | alloc_cluster_start = EXT4_B2C(sbi, lblk_start); | |
3412 | alloc_cluster_end = EXT4_B2C(sbi, lblk_start + num_blks - 1); | |
3413 | ||
3414 | /* max possible clusters for this allocation */ | |
3415 | allocated_clusters = alloc_cluster_end - alloc_cluster_start + 1; | |
3416 | ||
3417 | trace_ext4_get_reserved_cluster_alloc(inode, lblk_start, num_blks); | |
3418 | ||
3419 | /* Check towards left side */ | |
3420 | c_offset = lblk_start & (sbi->s_cluster_ratio - 1); | |
3421 | if (c_offset) { | |
3422 | lblk_from = lblk_start & (~(sbi->s_cluster_ratio - 1)); | |
3423 | lblk_to = lblk_from + c_offset - 1; | |
3424 | ||
3425 | if (ext4_find_delalloc_range(inode, lblk_from, lblk_to, 0)) | |
3426 | allocated_clusters--; | |
3427 | } | |
3428 | ||
3429 | /* Now check towards right. */ | |
3430 | c_offset = (lblk_start + num_blks) & (sbi->s_cluster_ratio - 1); | |
3431 | if (allocated_clusters && c_offset) { | |
3432 | lblk_from = lblk_start + num_blks; | |
3433 | lblk_to = lblk_from + (sbi->s_cluster_ratio - c_offset) - 1; | |
3434 | ||
3435 | if (ext4_find_delalloc_range(inode, lblk_from, lblk_to, 0)) | |
3436 | allocated_clusters--; | |
3437 | } | |
3438 | ||
3439 | return allocated_clusters; | |
3440 | } | |
3441 | ||
3442 | static int | |
3443 | ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode, | |
3444 | struct ext4_map_blocks *map, | |
3445 | struct ext4_ext_path *path, int flags, | |
3446 | unsigned int allocated, ext4_fsblk_t newblock) | |
3447 | { | |
3448 | int ret = 0; | |
3449 | int err = 0; | |
3450 | ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio; | |
3451 | ||
3452 | ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical" | |
3453 | "block %llu, max_blocks %u, flags %d, allocated %u", | |
3454 | inode->i_ino, (unsigned long long)map->m_lblk, map->m_len, | |
3455 | flags, allocated); | |
3456 | ext4_ext_show_leaf(inode, path); | |
3457 | ||
3458 | trace_ext4_ext_handle_uninitialized_extents(inode, map, allocated, | |
3459 | newblock); | |
3460 | ||
3461 | /* get_block() before submit the IO, split the extent */ | |
3462 | if ((flags & EXT4_GET_BLOCKS_PRE_IO)) { | |
3463 | ret = ext4_split_unwritten_extents(handle, inode, map, | |
3464 | path, flags); | |
3465 | /* | |
3466 | * Flag the inode(non aio case) or end_io struct (aio case) | |
3467 | * that this IO needs to conversion to written when IO is | |
3468 | * completed | |
3469 | */ | |
3470 | if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) { | |
3471 | io->flag = EXT4_IO_END_UNWRITTEN; | |
3472 | atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten); | |
3473 | } else | |
3474 | ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN); | |
3475 | if (ext4_should_dioread_nolock(inode)) | |
3476 | map->m_flags |= EXT4_MAP_UNINIT; | |
3477 | goto out; | |
3478 | } | |
3479 | /* IO end_io complete, convert the filled extent to written */ | |
3480 | if ((flags & EXT4_GET_BLOCKS_CONVERT)) { | |
3481 | ret = ext4_convert_unwritten_extents_endio(handle, inode, | |
3482 | path); | |
3483 | if (ret >= 0) { | |
3484 | ext4_update_inode_fsync_trans(handle, inode, 1); | |
3485 | err = check_eofblocks_fl(handle, inode, map->m_lblk, | |
3486 | path, map->m_len); | |
3487 | } else | |
3488 | err = ret; | |
3489 | goto out2; | |
3490 | } | |
3491 | /* buffered IO case */ | |
3492 | /* | |
3493 | * repeat fallocate creation request | |
3494 | * we already have an unwritten extent | |
3495 | */ | |
3496 | if (flags & EXT4_GET_BLOCKS_UNINIT_EXT) | |
3497 | goto map_out; | |
3498 | ||
3499 | /* buffered READ or buffered write_begin() lookup */ | |
3500 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) { | |
3501 | /* | |
3502 | * We have blocks reserved already. We | |
3503 | * return allocated blocks so that delalloc | |
3504 | * won't do block reservation for us. But | |
3505 | * the buffer head will be unmapped so that | |
3506 | * a read from the block returns 0s. | |
3507 | */ | |
3508 | map->m_flags |= EXT4_MAP_UNWRITTEN; | |
3509 | goto out1; | |
3510 | } | |
3511 | ||
3512 | /* buffered write, writepage time, convert*/ | |
3513 | ret = ext4_ext_convert_to_initialized(handle, inode, map, path); | |
3514 | if (ret >= 0) { | |
3515 | ext4_update_inode_fsync_trans(handle, inode, 1); | |
3516 | err = check_eofblocks_fl(handle, inode, map->m_lblk, path, | |
3517 | map->m_len); | |
3518 | if (err < 0) | |
3519 | goto out2; | |
3520 | } | |
3521 | ||
3522 | out: | |
3523 | if (ret <= 0) { | |
3524 | err = ret; | |
3525 | goto out2; | |
3526 | } else | |
3527 | allocated = ret; | |
3528 | map->m_flags |= EXT4_MAP_NEW; | |
3529 | /* | |
3530 | * if we allocated more blocks than requested | |
3531 | * we need to make sure we unmap the extra block | |
3532 | * allocated. The actual needed block will get | |
3533 | * unmapped later when we find the buffer_head marked | |
3534 | * new. | |
3535 | */ | |
3536 | if (allocated > map->m_len) { | |
3537 | unmap_underlying_metadata_blocks(inode->i_sb->s_bdev, | |
3538 | newblock + map->m_len, | |
3539 | allocated - map->m_len); | |
3540 | allocated = map->m_len; | |
3541 | } | |
3542 | ||
3543 | /* | |
3544 | * If we have done fallocate with the offset that is already | |
3545 | * delayed allocated, we would have block reservation | |
3546 | * and quota reservation done in the delayed write path. | |
3547 | * But fallocate would have already updated quota and block | |
3548 | * count for this offset. So cancel these reservation | |
3549 | */ | |
3550 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) { | |
3551 | unsigned int reserved_clusters; | |
3552 | reserved_clusters = get_reserved_cluster_alloc(inode, | |
3553 | map->m_lblk, map->m_len); | |
3554 | if (reserved_clusters) | |
3555 | ext4_da_update_reserve_space(inode, | |
3556 | reserved_clusters, | |
3557 | 0); | |
3558 | } | |
3559 | ||
3560 | map_out: | |
3561 | map->m_flags |= EXT4_MAP_MAPPED; | |
3562 | out1: | |
3563 | if (allocated > map->m_len) | |
3564 | allocated = map->m_len; | |
3565 | ext4_ext_show_leaf(inode, path); | |
3566 | map->m_pblk = newblock; | |
3567 | map->m_len = allocated; | |
3568 | out2: | |
3569 | if (path) { | |
3570 | ext4_ext_drop_refs(path); | |
3571 | kfree(path); | |
3572 | } | |
3573 | return err ? err : allocated; | |
3574 | } | |
3575 | ||
3576 | /* | |
3577 | * get_implied_cluster_alloc - check to see if the requested | |
3578 | * allocation (in the map structure) overlaps with a cluster already | |
3579 | * allocated in an extent. | |
3580 | * @sb The filesystem superblock structure | |
3581 | * @map The requested lblk->pblk mapping | |
3582 | * @ex The extent structure which might contain an implied | |
3583 | * cluster allocation | |
3584 | * | |
3585 | * This function is called by ext4_ext_map_blocks() after we failed to | |
3586 | * find blocks that were already in the inode's extent tree. Hence, | |
3587 | * we know that the beginning of the requested region cannot overlap | |
3588 | * the extent from the inode's extent tree. There are three cases we | |
3589 | * want to catch. The first is this case: | |
3590 | * | |
3591 | * |--- cluster # N--| | |
3592 | * |--- extent ---| |---- requested region ---| | |
3593 | * |==========| | |
3594 | * | |
3595 | * The second case that we need to test for is this one: | |
3596 | * | |
3597 | * |--------- cluster # N ----------------| | |
3598 | * |--- requested region --| |------- extent ----| | |
3599 | * |=======================| | |
3600 | * | |
3601 | * The third case is when the requested region lies between two extents | |
3602 | * within the same cluster: | |
3603 | * |------------- cluster # N-------------| | |
3604 | * |----- ex -----| |---- ex_right ----| | |
3605 | * |------ requested region ------| | |
3606 | * |================| | |
3607 | * | |
3608 | * In each of the above cases, we need to set the map->m_pblk and | |
3609 | * map->m_len so it corresponds to the return the extent labelled as | |
3610 | * "|====|" from cluster #N, since it is already in use for data in | |
3611 | * cluster EXT4_B2C(sbi, map->m_lblk). We will then return 1 to | |
3612 | * signal to ext4_ext_map_blocks() that map->m_pblk should be treated | |
3613 | * as a new "allocated" block region. Otherwise, we will return 0 and | |
3614 | * ext4_ext_map_blocks() will then allocate one or more new clusters | |
3615 | * by calling ext4_mb_new_blocks(). | |
3616 | */ | |
3617 | static int get_implied_cluster_alloc(struct super_block *sb, | |
3618 | struct ext4_map_blocks *map, | |
3619 | struct ext4_extent *ex, | |
3620 | struct ext4_ext_path *path) | |
3621 | { | |
3622 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
3623 | ext4_lblk_t c_offset = map->m_lblk & (sbi->s_cluster_ratio-1); | |
3624 | ext4_lblk_t ex_cluster_start, ex_cluster_end; | |
3625 | ext4_lblk_t rr_cluster_start, rr_cluster_end; | |
3626 | ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block); | |
3627 | ext4_fsblk_t ee_start = ext4_ext_pblock(ex); | |
3628 | unsigned short ee_len = ext4_ext_get_actual_len(ex); | |
3629 | ||
3630 | /* The extent passed in that we are trying to match */ | |
3631 | ex_cluster_start = EXT4_B2C(sbi, ee_block); | |
3632 | ex_cluster_end = EXT4_B2C(sbi, ee_block + ee_len - 1); | |
3633 | ||
3634 | /* The requested region passed into ext4_map_blocks() */ | |
3635 | rr_cluster_start = EXT4_B2C(sbi, map->m_lblk); | |
3636 | rr_cluster_end = EXT4_B2C(sbi, map->m_lblk + map->m_len - 1); | |
3637 | ||
3638 | if ((rr_cluster_start == ex_cluster_end) || | |
3639 | (rr_cluster_start == ex_cluster_start)) { | |
3640 | if (rr_cluster_start == ex_cluster_end) | |
3641 | ee_start += ee_len - 1; | |
3642 | map->m_pblk = (ee_start & ~(sbi->s_cluster_ratio - 1)) + | |
3643 | c_offset; | |
3644 | map->m_len = min(map->m_len, | |
3645 | (unsigned) sbi->s_cluster_ratio - c_offset); | |
3646 | /* | |
3647 | * Check for and handle this case: | |
3648 | * | |
3649 | * |--------- cluster # N-------------| | |
3650 | * |------- extent ----| | |
3651 | * |--- requested region ---| | |
3652 | * |===========| | |
3653 | */ | |
3654 | ||
3655 | if (map->m_lblk < ee_block) | |
3656 | map->m_len = min(map->m_len, ee_block - map->m_lblk); | |
3657 | ||
3658 | /* | |
3659 | * Check for the case where there is already another allocated | |
3660 | * block to the right of 'ex' but before the end of the cluster. | |
3661 | * | |
3662 | * |------------- cluster # N-------------| | |
3663 | * |----- ex -----| |---- ex_right ----| | |
3664 | * |------ requested region ------| | |
3665 | * |================| | |
3666 | */ | |
3667 | if (map->m_lblk > ee_block) { | |
3668 | ext4_lblk_t next = ext4_ext_next_allocated_block(path); | |
3669 | map->m_len = min(map->m_len, next - map->m_lblk); | |
3670 | } | |
3671 | ||
3672 | trace_ext4_get_implied_cluster_alloc_exit(sb, map, 1); | |
3673 | return 1; | |
3674 | } | |
3675 | ||
3676 | trace_ext4_get_implied_cluster_alloc_exit(sb, map, 0); | |
3677 | return 0; | |
3678 | } | |
3679 | ||
3680 | ||
3681 | /* | |
3682 | * Block allocation/map/preallocation routine for extents based files | |
3683 | * | |
3684 | * | |
3685 | * Need to be called with | |
3686 | * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block | |
3687 | * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem) | |
3688 | * | |
3689 | * return > 0, number of of blocks already mapped/allocated | |
3690 | * if create == 0 and these are pre-allocated blocks | |
3691 | * buffer head is unmapped | |
3692 | * otherwise blocks are mapped | |
3693 | * | |
3694 | * return = 0, if plain look up failed (blocks have not been allocated) | |
3695 | * buffer head is unmapped | |
3696 | * | |
3697 | * return < 0, error case. | |
3698 | */ | |
3699 | int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, | |
3700 | struct ext4_map_blocks *map, int flags) | |
3701 | { | |
3702 | struct ext4_ext_path *path = NULL; | |
3703 | struct ext4_extent newex, *ex, *ex2; | |
3704 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
3705 | ext4_fsblk_t newblock = 0; | |
3706 | int free_on_err = 0, err = 0, depth, ret; | |
3707 | unsigned int allocated = 0, offset = 0; | |
3708 | unsigned int allocated_clusters = 0, reserved_clusters = 0; | |
3709 | unsigned int punched_out = 0; | |
3710 | unsigned int result = 0; | |
3711 | struct ext4_allocation_request ar; | |
3712 | ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio; | |
3713 | ext4_lblk_t cluster_offset; | |
3714 | struct ext4_map_blocks punch_map; | |
3715 | ||
3716 | ext_debug("blocks %u/%u requested for inode %lu\n", | |
3717 | map->m_lblk, map->m_len, inode->i_ino); | |
3718 | trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags); | |
3719 | ||
3720 | /* check in cache */ | |
3721 | if (!(flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) && | |
3722 | ext4_ext_in_cache(inode, map->m_lblk, &newex)) { | |
3723 | if (!newex.ee_start_lo && !newex.ee_start_hi) { | |
3724 | if ((sbi->s_cluster_ratio > 1) && | |
3725 | ext4_find_delalloc_cluster(inode, map->m_lblk, 0)) | |
3726 | map->m_flags |= EXT4_MAP_FROM_CLUSTER; | |
3727 | ||
3728 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) { | |
3729 | /* | |
3730 | * block isn't allocated yet and | |
3731 | * user doesn't want to allocate it | |
3732 | */ | |
3733 | goto out2; | |
3734 | } | |
3735 | /* we should allocate requested block */ | |
3736 | } else { | |
3737 | /* block is already allocated */ | |
3738 | if (sbi->s_cluster_ratio > 1) | |
3739 | map->m_flags |= EXT4_MAP_FROM_CLUSTER; | |
3740 | newblock = map->m_lblk | |
3741 | - le32_to_cpu(newex.ee_block) | |
3742 | + ext4_ext_pblock(&newex); | |
3743 | /* number of remaining blocks in the extent */ | |
3744 | allocated = ext4_ext_get_actual_len(&newex) - | |
3745 | (map->m_lblk - le32_to_cpu(newex.ee_block)); | |
3746 | goto out; | |
3747 | } | |
3748 | } | |
3749 | ||
3750 | /* find extent for this block */ | |
3751 | path = ext4_ext_find_extent(inode, map->m_lblk, NULL); | |
3752 | if (IS_ERR(path)) { | |
3753 | err = PTR_ERR(path); | |
3754 | path = NULL; | |
3755 | goto out2; | |
3756 | } | |
3757 | ||
3758 | depth = ext_depth(inode); | |
3759 | ||
3760 | /* | |
3761 | * consistent leaf must not be empty; | |
3762 | * this situation is possible, though, _during_ tree modification; | |
3763 | * this is why assert can't be put in ext4_ext_find_extent() | |
3764 | */ | |
3765 | if (unlikely(path[depth].p_ext == NULL && depth != 0)) { | |
3766 | EXT4_ERROR_INODE(inode, "bad extent address " | |
3767 | "lblock: %lu, depth: %d pblock %lld", | |
3768 | (unsigned long) map->m_lblk, depth, | |
3769 | path[depth].p_block); | |
3770 | err = -EIO; | |
3771 | goto out2; | |
3772 | } | |
3773 | ||
3774 | ex = path[depth].p_ext; | |
3775 | if (ex) { | |
3776 | ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block); | |
3777 | ext4_fsblk_t ee_start = ext4_ext_pblock(ex); | |
3778 | unsigned short ee_len; | |
3779 | ||
3780 | /* | |
3781 | * Uninitialized extents are treated as holes, except that | |
3782 | * we split out initialized portions during a write. | |
3783 | */ | |
3784 | ee_len = ext4_ext_get_actual_len(ex); | |
3785 | ||
3786 | trace_ext4_ext_show_extent(inode, ee_block, ee_start, ee_len); | |
3787 | ||
3788 | /* if found extent covers block, simply return it */ | |
3789 | if (in_range(map->m_lblk, ee_block, ee_len)) { | |
3790 | ext4_fsblk_t partial_cluster = 0; | |
3791 | ||
3792 | newblock = map->m_lblk - ee_block + ee_start; | |
3793 | /* number of remaining blocks in the extent */ | |
3794 | allocated = ee_len - (map->m_lblk - ee_block); | |
3795 | ext_debug("%u fit into %u:%d -> %llu\n", map->m_lblk, | |
3796 | ee_block, ee_len, newblock); | |
3797 | ||
3798 | if ((flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) == 0) { | |
3799 | /* | |
3800 | * Do not put uninitialized extent | |
3801 | * in the cache | |
3802 | */ | |
3803 | if (!ext4_ext_is_uninitialized(ex)) { | |
3804 | ext4_ext_put_in_cache(inode, ee_block, | |
3805 | ee_len, ee_start); | |
3806 | goto out; | |
3807 | } | |
3808 | ret = ext4_ext_handle_uninitialized_extents( | |
3809 | handle, inode, map, path, flags, | |
3810 | allocated, newblock); | |
3811 | return ret; | |
3812 | } | |
3813 | ||
3814 | /* | |
3815 | * Punch out the map length, but only to the | |
3816 | * end of the extent | |
3817 | */ | |
3818 | punched_out = allocated < map->m_len ? | |
3819 | allocated : map->m_len; | |
3820 | ||
3821 | /* | |
3822 | * Sense extents need to be converted to | |
3823 | * uninitialized, they must fit in an | |
3824 | * uninitialized extent | |
3825 | */ | |
3826 | if (punched_out > EXT_UNINIT_MAX_LEN) | |
3827 | punched_out = EXT_UNINIT_MAX_LEN; | |
3828 | ||
3829 | punch_map.m_lblk = map->m_lblk; | |
3830 | punch_map.m_pblk = newblock; | |
3831 | punch_map.m_len = punched_out; | |
3832 | punch_map.m_flags = 0; | |
3833 | ||
3834 | /* Check to see if the extent needs to be split */ | |
3835 | if (punch_map.m_len != ee_len || | |
3836 | punch_map.m_lblk != ee_block) { | |
3837 | ||
3838 | ret = ext4_split_extent(handle, inode, | |
3839 | path, &punch_map, 0, | |
3840 | EXT4_GET_BLOCKS_PUNCH_OUT_EXT | | |
3841 | EXT4_GET_BLOCKS_PRE_IO); | |
3842 | ||
3843 | if (ret < 0) { | |
3844 | err = ret; | |
3845 | goto out2; | |
3846 | } | |
3847 | /* | |
3848 | * find extent for the block at | |
3849 | * the start of the hole | |
3850 | */ | |
3851 | ext4_ext_drop_refs(path); | |
3852 | kfree(path); | |
3853 | ||
3854 | path = ext4_ext_find_extent(inode, | |
3855 | map->m_lblk, NULL); | |
3856 | if (IS_ERR(path)) { | |
3857 | err = PTR_ERR(path); | |
3858 | path = NULL; | |
3859 | goto out2; | |
3860 | } | |
3861 | ||
3862 | depth = ext_depth(inode); | |
3863 | ex = path[depth].p_ext; | |
3864 | ee_len = ext4_ext_get_actual_len(ex); | |
3865 | ee_block = le32_to_cpu(ex->ee_block); | |
3866 | ee_start = ext4_ext_pblock(ex); | |
3867 | ||
3868 | } | |
3869 | ||
3870 | ext4_ext_mark_uninitialized(ex); | |
3871 | ||
3872 | ext4_ext_invalidate_cache(inode); | |
3873 | ||
3874 | err = ext4_ext_rm_leaf(handle, inode, path, | |
3875 | &partial_cluster, map->m_lblk, | |
3876 | map->m_lblk + punched_out); | |
3877 | ||
3878 | if (!err && path->p_hdr->eh_entries == 0) { | |
3879 | /* | |
3880 | * Punch hole freed all of this sub tree, | |
3881 | * so we need to correct eh_depth | |
3882 | */ | |
3883 | err = ext4_ext_get_access(handle, inode, path); | |
3884 | if (err == 0) { | |
3885 | ext_inode_hdr(inode)->eh_depth = 0; | |
3886 | ext_inode_hdr(inode)->eh_max = | |
3887 | cpu_to_le16(ext4_ext_space_root( | |
3888 | inode, 0)); | |
3889 | ||
3890 | err = ext4_ext_dirty( | |
3891 | handle, inode, path); | |
3892 | } | |
3893 | } | |
3894 | ||
3895 | goto out2; | |
3896 | } | |
3897 | } | |
3898 | ||
3899 | if ((sbi->s_cluster_ratio > 1) && | |
3900 | ext4_find_delalloc_cluster(inode, map->m_lblk, 0)) | |
3901 | map->m_flags |= EXT4_MAP_FROM_CLUSTER; | |
3902 | ||
3903 | /* | |
3904 | * requested block isn't allocated yet; | |
3905 | * we couldn't try to create block if create flag is zero | |
3906 | */ | |
3907 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) { | |
3908 | /* | |
3909 | * put just found gap into cache to speed up | |
3910 | * subsequent requests | |
3911 | */ | |
3912 | ext4_ext_put_gap_in_cache(inode, path, map->m_lblk); | |
3913 | goto out2; | |
3914 | } | |
3915 | ||
3916 | /* | |
3917 | * Okay, we need to do block allocation. | |
3918 | */ | |
3919 | map->m_flags &= ~EXT4_MAP_FROM_CLUSTER; | |
3920 | newex.ee_block = cpu_to_le32(map->m_lblk); | |
3921 | cluster_offset = map->m_lblk & (sbi->s_cluster_ratio-1); | |
3922 | ||
3923 | /* | |
3924 | * If we are doing bigalloc, check to see if the extent returned | |
3925 | * by ext4_ext_find_extent() implies a cluster we can use. | |
3926 | */ | |
3927 | if (cluster_offset && ex && | |
3928 | get_implied_cluster_alloc(inode->i_sb, map, ex, path)) { | |
3929 | ar.len = allocated = map->m_len; | |
3930 | newblock = map->m_pblk; | |
3931 | map->m_flags |= EXT4_MAP_FROM_CLUSTER; | |
3932 | goto got_allocated_blocks; | |
3933 | } | |
3934 | ||
3935 | /* find neighbour allocated blocks */ | |
3936 | ar.lleft = map->m_lblk; | |
3937 | err = ext4_ext_search_left(inode, path, &ar.lleft, &ar.pleft); | |
3938 | if (err) | |
3939 | goto out2; | |
3940 | ar.lright = map->m_lblk; | |
3941 | ex2 = NULL; | |
3942 | err = ext4_ext_search_right(inode, path, &ar.lright, &ar.pright, &ex2); | |
3943 | if (err) | |
3944 | goto out2; | |
3945 | ||
3946 | /* Check if the extent after searching to the right implies a | |
3947 | * cluster we can use. */ | |
3948 | if ((sbi->s_cluster_ratio > 1) && ex2 && | |
3949 | get_implied_cluster_alloc(inode->i_sb, map, ex2, path)) { | |
3950 | ar.len = allocated = map->m_len; | |
3951 | newblock = map->m_pblk; | |
3952 | map->m_flags |= EXT4_MAP_FROM_CLUSTER; | |
3953 | goto got_allocated_blocks; | |
3954 | } | |
3955 | ||
3956 | /* | |
3957 | * See if request is beyond maximum number of blocks we can have in | |
3958 | * a single extent. For an initialized extent this limit is | |
3959 | * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is | |
3960 | * EXT_UNINIT_MAX_LEN. | |
3961 | */ | |
3962 | if (map->m_len > EXT_INIT_MAX_LEN && | |
3963 | !(flags & EXT4_GET_BLOCKS_UNINIT_EXT)) | |
3964 | map->m_len = EXT_INIT_MAX_LEN; | |
3965 | else if (map->m_len > EXT_UNINIT_MAX_LEN && | |
3966 | (flags & EXT4_GET_BLOCKS_UNINIT_EXT)) | |
3967 | map->m_len = EXT_UNINIT_MAX_LEN; | |
3968 | ||
3969 | /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */ | |
3970 | newex.ee_len = cpu_to_le16(map->m_len); | |
3971 | err = ext4_ext_check_overlap(sbi, inode, &newex, path); | |
3972 | if (err) | |
3973 | allocated = ext4_ext_get_actual_len(&newex); | |
3974 | else | |
3975 | allocated = map->m_len; | |
3976 | ||
3977 | /* allocate new block */ | |
3978 | ar.inode = inode; | |
3979 | ar.goal = ext4_ext_find_goal(inode, path, map->m_lblk); | |
3980 | ar.logical = map->m_lblk; | |
3981 | /* | |
3982 | * We calculate the offset from the beginning of the cluster | |
3983 | * for the logical block number, since when we allocate a | |
3984 | * physical cluster, the physical block should start at the | |
3985 | * same offset from the beginning of the cluster. This is | |
3986 | * needed so that future calls to get_implied_cluster_alloc() | |
3987 | * work correctly. | |
3988 | */ | |
3989 | offset = map->m_lblk & (sbi->s_cluster_ratio - 1); | |
3990 | ar.len = EXT4_NUM_B2C(sbi, offset+allocated); | |
3991 | ar.goal -= offset; | |
3992 | ar.logical -= offset; | |
3993 | if (S_ISREG(inode->i_mode)) | |
3994 | ar.flags = EXT4_MB_HINT_DATA; | |
3995 | else | |
3996 | /* disable in-core preallocation for non-regular files */ | |
3997 | ar.flags = 0; | |
3998 | if (flags & EXT4_GET_BLOCKS_NO_NORMALIZE) | |
3999 | ar.flags |= EXT4_MB_HINT_NOPREALLOC; | |
4000 | newblock = ext4_mb_new_blocks(handle, &ar, &err); | |
4001 | if (!newblock) | |
4002 | goto out2; | |
4003 | ext_debug("allocate new block: goal %llu, found %llu/%u\n", | |
4004 | ar.goal, newblock, allocated); | |
4005 | free_on_err = 1; | |
4006 | allocated_clusters = ar.len; | |
4007 | ar.len = EXT4_C2B(sbi, ar.len) - offset; | |
4008 | if (ar.len > allocated) | |
4009 | ar.len = allocated; | |
4010 | ||
4011 | got_allocated_blocks: | |
4012 | /* try to insert new extent into found leaf and return */ | |
4013 | ext4_ext_store_pblock(&newex, newblock + offset); | |
4014 | newex.ee_len = cpu_to_le16(ar.len); | |
4015 | /* Mark uninitialized */ | |
4016 | if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){ | |
4017 | ext4_ext_mark_uninitialized(&newex); | |
4018 | /* | |
4019 | * io_end structure was created for every IO write to an | |
4020 | * uninitialized extent. To avoid unnecessary conversion, | |
4021 | * here we flag the IO that really needs the conversion. | |
4022 | * For non asycn direct IO case, flag the inode state | |
4023 | * that we need to perform conversion when IO is done. | |
4024 | */ | |
4025 | if ((flags & EXT4_GET_BLOCKS_PRE_IO)) { | |
4026 | if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) { | |
4027 | io->flag = EXT4_IO_END_UNWRITTEN; | |
4028 | atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten); | |
4029 | } else | |
4030 | ext4_set_inode_state(inode, | |
4031 | EXT4_STATE_DIO_UNWRITTEN); | |
4032 | } | |
4033 | if (ext4_should_dioread_nolock(inode)) | |
4034 | map->m_flags |= EXT4_MAP_UNINIT; | |
4035 | } | |
4036 | ||
4037 | err = check_eofblocks_fl(handle, inode, map->m_lblk, path, ar.len); | |
4038 | if (!err) | |
4039 | err = ext4_ext_insert_extent(handle, inode, path, | |
4040 | &newex, flags); | |
4041 | if (err && free_on_err) { | |
4042 | int fb_flags = flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE ? | |
4043 | EXT4_FREE_BLOCKS_NO_QUOT_UPDATE : 0; | |
4044 | /* free data blocks we just allocated */ | |
4045 | /* not a good idea to call discard here directly, | |
4046 | * but otherwise we'd need to call it every free() */ | |
4047 | ext4_discard_preallocations(inode); | |
4048 | ext4_free_blocks(handle, inode, NULL, ext4_ext_pblock(&newex), | |
4049 | ext4_ext_get_actual_len(&newex), fb_flags); | |
4050 | goto out2; | |
4051 | } | |
4052 | ||
4053 | /* previous routine could use block we allocated */ | |
4054 | newblock = ext4_ext_pblock(&newex); | |
4055 | allocated = ext4_ext_get_actual_len(&newex); | |
4056 | if (allocated > map->m_len) | |
4057 | allocated = map->m_len; | |
4058 | map->m_flags |= EXT4_MAP_NEW; | |
4059 | ||
4060 | /* | |
4061 | * Update reserved blocks/metadata blocks after successful | |
4062 | * block allocation which had been deferred till now. | |
4063 | */ | |
4064 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) { | |
4065 | /* | |
4066 | * Check how many clusters we had reserved this allocted range. | |
4067 | */ | |
4068 | reserved_clusters = get_reserved_cluster_alloc(inode, | |
4069 | map->m_lblk, allocated); | |
4070 | if (map->m_flags & EXT4_MAP_FROM_CLUSTER) { | |
4071 | if (reserved_clusters) { | |
4072 | /* | |
4073 | * We have clusters reserved for this range. | |
4074 | * But since we are not doing actual allocation | |
4075 | * and are simply using blocks from previously | |
4076 | * allocated cluster, we should release the | |
4077 | * reservation and not claim quota. | |
4078 | */ | |
4079 | ext4_da_update_reserve_space(inode, | |
4080 | reserved_clusters, 0); | |
4081 | } | |
4082 | } else { | |
4083 | BUG_ON(allocated_clusters < reserved_clusters); | |
4084 | /* We will claim quota for all newly allocated blocks.*/ | |
4085 | ext4_da_update_reserve_space(inode, allocated_clusters, | |
4086 | 1); | |
4087 | if (reserved_clusters < allocated_clusters) { | |
4088 | struct ext4_inode_info *ei = EXT4_I(inode); | |
4089 | int reservation = allocated_clusters - | |
4090 | reserved_clusters; | |
4091 | /* | |
4092 | * It seems we claimed few clusters outside of | |
4093 | * the range of this allocation. We should give | |
4094 | * it back to the reservation pool. This can | |
4095 | * happen in the following case: | |
4096 | * | |
4097 | * * Suppose s_cluster_ratio is 4 (i.e., each | |
4098 | * cluster has 4 blocks. Thus, the clusters | |
4099 | * are [0-3],[4-7],[8-11]... | |
4100 | * * First comes delayed allocation write for | |
4101 | * logical blocks 10 & 11. Since there were no | |
4102 | * previous delayed allocated blocks in the | |
4103 | * range [8-11], we would reserve 1 cluster | |
4104 | * for this write. | |
4105 | * * Next comes write for logical blocks 3 to 8. | |
4106 | * In this case, we will reserve 2 clusters | |
4107 | * (for [0-3] and [4-7]; and not for [8-11] as | |
4108 | * that range has a delayed allocated blocks. | |
4109 | * Thus total reserved clusters now becomes 3. | |
4110 | * * Now, during the delayed allocation writeout | |
4111 | * time, we will first write blocks [3-8] and | |
4112 | * allocate 3 clusters for writing these | |
4113 | * blocks. Also, we would claim all these | |
4114 | * three clusters above. | |
4115 | * * Now when we come here to writeout the | |
4116 | * blocks [10-11], we would expect to claim | |
4117 | * the reservation of 1 cluster we had made | |
4118 | * (and we would claim it since there are no | |
4119 | * more delayed allocated blocks in the range | |
4120 | * [8-11]. But our reserved cluster count had | |
4121 | * already gone to 0. | |
4122 | * | |
4123 | * Thus, at the step 4 above when we determine | |
4124 | * that there are still some unwritten delayed | |
4125 | * allocated blocks outside of our current | |
4126 | * block range, we should increment the | |
4127 | * reserved clusters count so that when the | |
4128 | * remaining blocks finally gets written, we | |
4129 | * could claim them. | |
4130 | */ | |
4131 | dquot_reserve_block(inode, | |
4132 | EXT4_C2B(sbi, reservation)); | |
4133 | spin_lock(&ei->i_block_reservation_lock); | |
4134 | ei->i_reserved_data_blocks += reservation; | |
4135 | spin_unlock(&ei->i_block_reservation_lock); | |
4136 | } | |
4137 | } | |
4138 | } | |
4139 | ||
4140 | /* | |
4141 | * Cache the extent and update transaction to commit on fdatasync only | |
4142 | * when it is _not_ an uninitialized extent. | |
4143 | */ | |
4144 | if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0) { | |
4145 | ext4_ext_put_in_cache(inode, map->m_lblk, allocated, newblock); | |
4146 | ext4_update_inode_fsync_trans(handle, inode, 1); | |
4147 | } else | |
4148 | ext4_update_inode_fsync_trans(handle, inode, 0); | |
4149 | out: | |
4150 | if (allocated > map->m_len) | |
4151 | allocated = map->m_len; | |
4152 | ext4_ext_show_leaf(inode, path); | |
4153 | map->m_flags |= EXT4_MAP_MAPPED; | |
4154 | map->m_pblk = newblock; | |
4155 | map->m_len = allocated; | |
4156 | out2: | |
4157 | if (path) { | |
4158 | ext4_ext_drop_refs(path); | |
4159 | kfree(path); | |
4160 | } | |
4161 | trace_ext4_ext_map_blocks_exit(inode, map->m_lblk, | |
4162 | newblock, map->m_len, err ? err : allocated); | |
4163 | ||
4164 | result = (flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) ? | |
4165 | punched_out : allocated; | |
4166 | ||
4167 | return err ? err : result; | |
4168 | } | |
4169 | ||
4170 | void ext4_ext_truncate(struct inode *inode) | |
4171 | { | |
4172 | struct address_space *mapping = inode->i_mapping; | |
4173 | struct super_block *sb = inode->i_sb; | |
4174 | ext4_lblk_t last_block; | |
4175 | handle_t *handle; | |
4176 | loff_t page_len; | |
4177 | int err = 0; | |
4178 | ||
4179 | /* | |
4180 | * finish any pending end_io work so we won't run the risk of | |
4181 | * converting any truncated blocks to initialized later | |
4182 | */ | |
4183 | ext4_flush_completed_IO(inode); | |
4184 | ||
4185 | /* | |
4186 | * probably first extent we're gonna free will be last in block | |
4187 | */ | |
4188 | err = ext4_writepage_trans_blocks(inode); | |
4189 | handle = ext4_journal_start(inode, err); | |
4190 | if (IS_ERR(handle)) | |
4191 | return; | |
4192 | ||
4193 | if (inode->i_size % PAGE_CACHE_SIZE != 0) { | |
4194 | page_len = PAGE_CACHE_SIZE - | |
4195 | (inode->i_size & (PAGE_CACHE_SIZE - 1)); | |
4196 | ||
4197 | err = ext4_discard_partial_page_buffers(handle, | |
4198 | mapping, inode->i_size, page_len, 0); | |
4199 | ||
4200 | if (err) | |
4201 | goto out_stop; | |
4202 | } | |
4203 | ||
4204 | if (ext4_orphan_add(handle, inode)) | |
4205 | goto out_stop; | |
4206 | ||
4207 | down_write(&EXT4_I(inode)->i_data_sem); | |
4208 | ext4_ext_invalidate_cache(inode); | |
4209 | ||
4210 | ext4_discard_preallocations(inode); | |
4211 | ||
4212 | /* | |
4213 | * TODO: optimization is possible here. | |
4214 | * Probably we need not scan at all, | |
4215 | * because page truncation is enough. | |
4216 | */ | |
4217 | ||
4218 | /* we have to know where to truncate from in crash case */ | |
4219 | EXT4_I(inode)->i_disksize = inode->i_size; | |
4220 | ext4_mark_inode_dirty(handle, inode); | |
4221 | ||
4222 | last_block = (inode->i_size + sb->s_blocksize - 1) | |
4223 | >> EXT4_BLOCK_SIZE_BITS(sb); | |
4224 | err = ext4_ext_remove_space(inode, last_block); | |
4225 | ||
4226 | /* In a multi-transaction truncate, we only make the final | |
4227 | * transaction synchronous. | |
4228 | */ | |
4229 | if (IS_SYNC(inode)) | |
4230 | ext4_handle_sync(handle); | |
4231 | ||
4232 | up_write(&EXT4_I(inode)->i_data_sem); | |
4233 | ||
4234 | out_stop: | |
4235 | /* | |
4236 | * If this was a simple ftruncate() and the file will remain alive, | |
4237 | * then we need to clear up the orphan record which we created above. | |
4238 | * However, if this was a real unlink then we were called by | |
4239 | * ext4_delete_inode(), and we allow that function to clean up the | |
4240 | * orphan info for us. | |
4241 | */ | |
4242 | if (inode->i_nlink) | |
4243 | ext4_orphan_del(handle, inode); | |
4244 | ||
4245 | inode->i_mtime = inode->i_ctime = ext4_current_time(inode); | |
4246 | ext4_mark_inode_dirty(handle, inode); | |
4247 | ext4_journal_stop(handle); | |
4248 | } | |
4249 | ||
4250 | static void ext4_falloc_update_inode(struct inode *inode, | |
4251 | int mode, loff_t new_size, int update_ctime) | |
4252 | { | |
4253 | struct timespec now; | |
4254 | ||
4255 | if (update_ctime) { | |
4256 | now = current_fs_time(inode->i_sb); | |
4257 | if (!timespec_equal(&inode->i_ctime, &now)) | |
4258 | inode->i_ctime = now; | |
4259 | } | |
4260 | /* | |
4261 | * Update only when preallocation was requested beyond | |
4262 | * the file size. | |
4263 | */ | |
4264 | if (!(mode & FALLOC_FL_KEEP_SIZE)) { | |
4265 | if (new_size > i_size_read(inode)) | |
4266 | i_size_write(inode, new_size); | |
4267 | if (new_size > EXT4_I(inode)->i_disksize) | |
4268 | ext4_update_i_disksize(inode, new_size); | |
4269 | } else { | |
4270 | /* | |
4271 | * Mark that we allocate beyond EOF so the subsequent truncate | |
4272 | * can proceed even if the new size is the same as i_size. | |
4273 | */ | |
4274 | if (new_size > i_size_read(inode)) | |
4275 | ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS); | |
4276 | } | |
4277 | ||
4278 | } | |
4279 | ||
4280 | /* | |
4281 | * preallocate space for a file. This implements ext4's fallocate file | |
4282 | * operation, which gets called from sys_fallocate system call. | |
4283 | * For block-mapped files, posix_fallocate should fall back to the method | |
4284 | * of writing zeroes to the required new blocks (the same behavior which is | |
4285 | * expected for file systems which do not support fallocate() system call). | |
4286 | */ | |
4287 | long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len) | |
4288 | { | |
4289 | struct inode *inode = file->f_path.dentry->d_inode; | |
4290 | handle_t *handle; | |
4291 | loff_t new_size; | |
4292 | unsigned int max_blocks; | |
4293 | int ret = 0; | |
4294 | int ret2 = 0; | |
4295 | int retries = 0; | |
4296 | struct ext4_map_blocks map; | |
4297 | unsigned int credits, blkbits = inode->i_blkbits; | |
4298 | ||
4299 | /* | |
4300 | * currently supporting (pre)allocate mode for extent-based | |
4301 | * files _only_ | |
4302 | */ | |
4303 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) | |
4304 | return -EOPNOTSUPP; | |
4305 | ||
4306 | /* Return error if mode is not supported */ | |
4307 | if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) | |
4308 | return -EOPNOTSUPP; | |
4309 | ||
4310 | if (mode & FALLOC_FL_PUNCH_HOLE) | |
4311 | return ext4_punch_hole(file, offset, len); | |
4312 | ||
4313 | trace_ext4_fallocate_enter(inode, offset, len, mode); | |
4314 | map.m_lblk = offset >> blkbits; | |
4315 | /* | |
4316 | * We can't just convert len to max_blocks because | |
4317 | * If blocksize = 4096 offset = 3072 and len = 2048 | |
4318 | */ | |
4319 | max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) | |
4320 | - map.m_lblk; | |
4321 | /* | |
4322 | * credits to insert 1 extent into extent tree | |
4323 | */ | |
4324 | credits = ext4_chunk_trans_blocks(inode, max_blocks); | |
4325 | mutex_lock(&inode->i_mutex); | |
4326 | ret = inode_newsize_ok(inode, (len + offset)); | |
4327 | if (ret) { | |
4328 | mutex_unlock(&inode->i_mutex); | |
4329 | trace_ext4_fallocate_exit(inode, offset, max_blocks, ret); | |
4330 | return ret; | |
4331 | } | |
4332 | retry: | |
4333 | while (ret >= 0 && ret < max_blocks) { | |
4334 | map.m_lblk = map.m_lblk + ret; | |
4335 | map.m_len = max_blocks = max_blocks - ret; | |
4336 | handle = ext4_journal_start(inode, credits); | |
4337 | if (IS_ERR(handle)) { | |
4338 | ret = PTR_ERR(handle); | |
4339 | break; | |
4340 | } | |
4341 | ret = ext4_map_blocks(handle, inode, &map, | |
4342 | EXT4_GET_BLOCKS_CREATE_UNINIT_EXT | | |
4343 | EXT4_GET_BLOCKS_NO_NORMALIZE); | |
4344 | if (ret <= 0) { | |
4345 | #ifdef EXT4FS_DEBUG | |
4346 | WARN_ON(ret <= 0); | |
4347 | printk(KERN_ERR "%s: ext4_ext_map_blocks " | |
4348 | "returned error inode#%lu, block=%u, " | |
4349 | "max_blocks=%u", __func__, | |
4350 | inode->i_ino, map.m_lblk, max_blocks); | |
4351 | #endif | |
4352 | ext4_mark_inode_dirty(handle, inode); | |
4353 | ret2 = ext4_journal_stop(handle); | |
4354 | break; | |
4355 | } | |
4356 | if ((map.m_lblk + ret) >= (EXT4_BLOCK_ALIGN(offset + len, | |
4357 | blkbits) >> blkbits)) | |
4358 | new_size = offset + len; | |
4359 | else | |
4360 | new_size = ((loff_t) map.m_lblk + ret) << blkbits; | |
4361 | ||
4362 | ext4_falloc_update_inode(inode, mode, new_size, | |
4363 | (map.m_flags & EXT4_MAP_NEW)); | |
4364 | ext4_mark_inode_dirty(handle, inode); | |
4365 | ret2 = ext4_journal_stop(handle); | |
4366 | if (ret2) | |
4367 | break; | |
4368 | } | |
4369 | if (ret == -ENOSPC && | |
4370 | ext4_should_retry_alloc(inode->i_sb, &retries)) { | |
4371 | ret = 0; | |
4372 | goto retry; | |
4373 | } | |
4374 | mutex_unlock(&inode->i_mutex); | |
4375 | trace_ext4_fallocate_exit(inode, offset, max_blocks, | |
4376 | ret > 0 ? ret2 : ret); | |
4377 | return ret > 0 ? ret2 : ret; | |
4378 | } | |
4379 | ||
4380 | /* | |
4381 | * This function convert a range of blocks to written extents | |
4382 | * The caller of this function will pass the start offset and the size. | |
4383 | * all unwritten extents within this range will be converted to | |
4384 | * written extents. | |
4385 | * | |
4386 | * This function is called from the direct IO end io call back | |
4387 | * function, to convert the fallocated extents after IO is completed. | |
4388 | * Returns 0 on success. | |
4389 | */ | |
4390 | int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset, | |
4391 | ssize_t len) | |
4392 | { | |
4393 | handle_t *handle; | |
4394 | unsigned int max_blocks; | |
4395 | int ret = 0; | |
4396 | int ret2 = 0; | |
4397 | struct ext4_map_blocks map; | |
4398 | unsigned int credits, blkbits = inode->i_blkbits; | |
4399 | ||
4400 | map.m_lblk = offset >> blkbits; | |
4401 | /* | |
4402 | * We can't just convert len to max_blocks because | |
4403 | * If blocksize = 4096 offset = 3072 and len = 2048 | |
4404 | */ | |
4405 | max_blocks = ((EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) - | |
4406 | map.m_lblk); | |
4407 | /* | |
4408 | * credits to insert 1 extent into extent tree | |
4409 | */ | |
4410 | credits = ext4_chunk_trans_blocks(inode, max_blocks); | |
4411 | while (ret >= 0 && ret < max_blocks) { | |
4412 | map.m_lblk += ret; | |
4413 | map.m_len = (max_blocks -= ret); | |
4414 | handle = ext4_journal_start(inode, credits); | |
4415 | if (IS_ERR(handle)) { | |
4416 | ret = PTR_ERR(handle); | |
4417 | break; | |
4418 | } | |
4419 | ret = ext4_map_blocks(handle, inode, &map, | |
4420 | EXT4_GET_BLOCKS_IO_CONVERT_EXT); | |
4421 | if (ret <= 0) { | |
4422 | WARN_ON(ret <= 0); | |
4423 | printk(KERN_ERR "%s: ext4_ext_map_blocks " | |
4424 | "returned error inode#%lu, block=%u, " | |
4425 | "max_blocks=%u", __func__, | |
4426 | inode->i_ino, map.m_lblk, map.m_len); | |
4427 | } | |
4428 | ext4_mark_inode_dirty(handle, inode); | |
4429 | ret2 = ext4_journal_stop(handle); | |
4430 | if (ret <= 0 || ret2 ) | |
4431 | break; | |
4432 | } | |
4433 | return ret > 0 ? ret2 : ret; | |
4434 | } | |
4435 | ||
4436 | /* | |
4437 | * Callback function called for each extent to gather FIEMAP information. | |
4438 | */ | |
4439 | static int ext4_ext_fiemap_cb(struct inode *inode, ext4_lblk_t next, | |
4440 | struct ext4_ext_cache *newex, struct ext4_extent *ex, | |
4441 | void *data) | |
4442 | { | |
4443 | __u64 logical; | |
4444 | __u64 physical; | |
4445 | __u64 length; | |
4446 | __u32 flags = 0; | |
4447 | int ret = 0; | |
4448 | struct fiemap_extent_info *fieinfo = data; | |
4449 | unsigned char blksize_bits; | |
4450 | ||
4451 | blksize_bits = inode->i_sb->s_blocksize_bits; | |
4452 | logical = (__u64)newex->ec_block << blksize_bits; | |
4453 | ||
4454 | if (newex->ec_start == 0) { | |
4455 | /* | |
4456 | * No extent in extent-tree contains block @newex->ec_start, | |
4457 | * then the block may stay in 1)a hole or 2)delayed-extent. | |
4458 | * | |
4459 | * Holes or delayed-extents are processed as follows. | |
4460 | * 1. lookup dirty pages with specified range in pagecache. | |
4461 | * If no page is got, then there is no delayed-extent and | |
4462 | * return with EXT_CONTINUE. | |
4463 | * 2. find the 1st mapped buffer, | |
4464 | * 3. check if the mapped buffer is both in the request range | |
4465 | * and a delayed buffer. If not, there is no delayed-extent, | |
4466 | * then return. | |
4467 | * 4. a delayed-extent is found, the extent will be collected. | |
4468 | */ | |
4469 | ext4_lblk_t end = 0; | |
4470 | pgoff_t last_offset; | |
4471 | pgoff_t offset; | |
4472 | pgoff_t index; | |
4473 | pgoff_t start_index = 0; | |
4474 | struct page **pages = NULL; | |
4475 | struct buffer_head *bh = NULL; | |
4476 | struct buffer_head *head = NULL; | |
4477 | unsigned int nr_pages = PAGE_SIZE / sizeof(struct page *); | |
4478 | ||
4479 | pages = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
4480 | if (pages == NULL) | |
4481 | return -ENOMEM; | |
4482 | ||
4483 | offset = logical >> PAGE_SHIFT; | |
4484 | repeat: | |
4485 | last_offset = offset; | |
4486 | head = NULL; | |
4487 | ret = find_get_pages_tag(inode->i_mapping, &offset, | |
4488 | PAGECACHE_TAG_DIRTY, nr_pages, pages); | |
4489 | ||
4490 | if (!(flags & FIEMAP_EXTENT_DELALLOC)) { | |
4491 | /* First time, try to find a mapped buffer. */ | |
4492 | if (ret == 0) { | |
4493 | out: | |
4494 | for (index = 0; index < ret; index++) | |
4495 | page_cache_release(pages[index]); | |
4496 | /* just a hole. */ | |
4497 | kfree(pages); | |
4498 | return EXT_CONTINUE; | |
4499 | } | |
4500 | index = 0; | |
4501 | ||
4502 | next_page: | |
4503 | /* Try to find the 1st mapped buffer. */ | |
4504 | end = ((__u64)pages[index]->index << PAGE_SHIFT) >> | |
4505 | blksize_bits; | |
4506 | if (!page_has_buffers(pages[index])) | |
4507 | goto out; | |
4508 | head = page_buffers(pages[index]); | |
4509 | if (!head) | |
4510 | goto out; | |
4511 | ||
4512 | index++; | |
4513 | bh = head; | |
4514 | do { | |
4515 | if (end >= newex->ec_block + | |
4516 | newex->ec_len) | |
4517 | /* The buffer is out of | |
4518 | * the request range. | |
4519 | */ | |
4520 | goto out; | |
4521 | ||
4522 | if (buffer_mapped(bh) && | |
4523 | end >= newex->ec_block) { | |
4524 | start_index = index - 1; | |
4525 | /* get the 1st mapped buffer. */ | |
4526 | goto found_mapped_buffer; | |
4527 | } | |
4528 | ||
4529 | bh = bh->b_this_page; | |
4530 | end++; | |
4531 | } while (bh != head); | |
4532 | ||
4533 | /* No mapped buffer in the range found in this page, | |
4534 | * We need to look up next page. | |
4535 | */ | |
4536 | if (index >= ret) { | |
4537 | /* There is no page left, but we need to limit | |
4538 | * newex->ec_len. | |
4539 | */ | |
4540 | newex->ec_len = end - newex->ec_block; | |
4541 | goto out; | |
4542 | } | |
4543 | goto next_page; | |
4544 | } else { | |
4545 | /*Find contiguous delayed buffers. */ | |
4546 | if (ret > 0 && pages[0]->index == last_offset) | |
4547 | head = page_buffers(pages[0]); | |
4548 | bh = head; | |
4549 | index = 1; | |
4550 | start_index = 0; | |
4551 | } | |
4552 | ||
4553 | found_mapped_buffer: | |
4554 | if (bh != NULL && buffer_delay(bh)) { | |
4555 | /* 1st or contiguous delayed buffer found. */ | |
4556 | if (!(flags & FIEMAP_EXTENT_DELALLOC)) { | |
4557 | /* | |
4558 | * 1st delayed buffer found, record | |
4559 | * the start of extent. | |
4560 | */ | |
4561 | flags |= FIEMAP_EXTENT_DELALLOC; | |
4562 | newex->ec_block = end; | |
4563 | logical = (__u64)end << blksize_bits; | |
4564 | } | |
4565 | /* Find contiguous delayed buffers. */ | |
4566 | do { | |
4567 | if (!buffer_delay(bh)) | |
4568 | goto found_delayed_extent; | |
4569 | bh = bh->b_this_page; | |
4570 | end++; | |
4571 | } while (bh != head); | |
4572 | ||
4573 | for (; index < ret; index++) { | |
4574 | if (!page_has_buffers(pages[index])) { | |
4575 | bh = NULL; | |
4576 | break; | |
4577 | } | |
4578 | head = page_buffers(pages[index]); | |
4579 | if (!head) { | |
4580 | bh = NULL; | |
4581 | break; | |
4582 | } | |
4583 | ||
4584 | if (pages[index]->index != | |
4585 | pages[start_index]->index + index | |
4586 | - start_index) { | |
4587 | /* Blocks are not contiguous. */ | |
4588 | bh = NULL; | |
4589 | break; | |
4590 | } | |
4591 | bh = head; | |
4592 | do { | |
4593 | if (!buffer_delay(bh)) | |
4594 | /* Delayed-extent ends. */ | |
4595 | goto found_delayed_extent; | |
4596 | bh = bh->b_this_page; | |
4597 | end++; | |
4598 | } while (bh != head); | |
4599 | } | |
4600 | } else if (!(flags & FIEMAP_EXTENT_DELALLOC)) | |
4601 | /* a hole found. */ | |
4602 | goto out; | |
4603 | ||
4604 | found_delayed_extent: | |
4605 | newex->ec_len = min(end - newex->ec_block, | |
4606 | (ext4_lblk_t)EXT_INIT_MAX_LEN); | |
4607 | if (ret == nr_pages && bh != NULL && | |
4608 | newex->ec_len < EXT_INIT_MAX_LEN && | |
4609 | buffer_delay(bh)) { | |
4610 | /* Have not collected an extent and continue. */ | |
4611 | for (index = 0; index < ret; index++) | |
4612 | page_cache_release(pages[index]); | |
4613 | goto repeat; | |
4614 | } | |
4615 | ||
4616 | for (index = 0; index < ret; index++) | |
4617 | page_cache_release(pages[index]); | |
4618 | kfree(pages); | |
4619 | } | |
4620 | ||
4621 | physical = (__u64)newex->ec_start << blksize_bits; | |
4622 | length = (__u64)newex->ec_len << blksize_bits; | |
4623 | ||
4624 | if (ex && ext4_ext_is_uninitialized(ex)) | |
4625 | flags |= FIEMAP_EXTENT_UNWRITTEN; | |
4626 | ||
4627 | if (next == EXT_MAX_BLOCKS) | |
4628 | flags |= FIEMAP_EXTENT_LAST; | |
4629 | ||
4630 | ret = fiemap_fill_next_extent(fieinfo, logical, physical, | |
4631 | length, flags); | |
4632 | if (ret < 0) | |
4633 | return ret; | |
4634 | if (ret == 1) | |
4635 | return EXT_BREAK; | |
4636 | return EXT_CONTINUE; | |
4637 | } | |
4638 | /* fiemap flags we can handle specified here */ | |
4639 | #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR) | |
4640 | ||
4641 | static int ext4_xattr_fiemap(struct inode *inode, | |
4642 | struct fiemap_extent_info *fieinfo) | |
4643 | { | |
4644 | __u64 physical = 0; | |
4645 | __u64 length; | |
4646 | __u32 flags = FIEMAP_EXTENT_LAST; | |
4647 | int blockbits = inode->i_sb->s_blocksize_bits; | |
4648 | int error = 0; | |
4649 | ||
4650 | /* in-inode? */ | |
4651 | if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { | |
4652 | struct ext4_iloc iloc; | |
4653 | int offset; /* offset of xattr in inode */ | |
4654 | ||
4655 | error = ext4_get_inode_loc(inode, &iloc); | |
4656 | if (error) | |
4657 | return error; | |
4658 | physical = iloc.bh->b_blocknr << blockbits; | |
4659 | offset = EXT4_GOOD_OLD_INODE_SIZE + | |
4660 | EXT4_I(inode)->i_extra_isize; | |
4661 | physical += offset; | |
4662 | length = EXT4_SB(inode->i_sb)->s_inode_size - offset; | |
4663 | flags |= FIEMAP_EXTENT_DATA_INLINE; | |
4664 | brelse(iloc.bh); | |
4665 | } else { /* external block */ | |
4666 | physical = EXT4_I(inode)->i_file_acl << blockbits; | |
4667 | length = inode->i_sb->s_blocksize; | |
4668 | } | |
4669 | ||
4670 | if (physical) | |
4671 | error = fiemap_fill_next_extent(fieinfo, 0, physical, | |
4672 | length, flags); | |
4673 | return (error < 0 ? error : 0); | |
4674 | } | |
4675 | ||
4676 | /* | |
4677 | * ext4_ext_punch_hole | |
4678 | * | |
4679 | * Punches a hole of "length" bytes in a file starting | |
4680 | * at byte "offset" | |
4681 | * | |
4682 | * @inode: The inode of the file to punch a hole in | |
4683 | * @offset: The starting byte offset of the hole | |
4684 | * @length: The length of the hole | |
4685 | * | |
4686 | * Returns the number of blocks removed or negative on err | |
4687 | */ | |
4688 | int ext4_ext_punch_hole(struct file *file, loff_t offset, loff_t length) | |
4689 | { | |
4690 | struct inode *inode = file->f_path.dentry->d_inode; | |
4691 | struct super_block *sb = inode->i_sb; | |
4692 | struct ext4_ext_cache cache_ex; | |
4693 | ext4_lblk_t first_block, last_block, num_blocks, iblock, max_blocks; | |
4694 | struct address_space *mapping = inode->i_mapping; | |
4695 | struct ext4_map_blocks map; | |
4696 | handle_t *handle; | |
4697 | loff_t first_page, last_page, page_len; | |
4698 | loff_t first_page_offset, last_page_offset; | |
4699 | int ret, credits, blocks_released, err = 0; | |
4700 | ||
4701 | /* No need to punch hole beyond i_size */ | |
4702 | if (offset >= inode->i_size) | |
4703 | return 0; | |
4704 | ||
4705 | /* | |
4706 | * If the hole extends beyond i_size, set the hole | |
4707 | * to end after the page that contains i_size | |
4708 | */ | |
4709 | if (offset + length > inode->i_size) { | |
4710 | length = inode->i_size + | |
4711 | PAGE_CACHE_SIZE - (inode->i_size & (PAGE_CACHE_SIZE - 1)) - | |
4712 | offset; | |
4713 | } | |
4714 | ||
4715 | first_block = (offset + sb->s_blocksize - 1) >> | |
4716 | EXT4_BLOCK_SIZE_BITS(sb); | |
4717 | last_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb); | |
4718 | ||
4719 | first_page = (offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; | |
4720 | last_page = (offset + length) >> PAGE_CACHE_SHIFT; | |
4721 | ||
4722 | first_page_offset = first_page << PAGE_CACHE_SHIFT; | |
4723 | last_page_offset = last_page << PAGE_CACHE_SHIFT; | |
4724 | ||
4725 | /* | |
4726 | * Write out all dirty pages to avoid race conditions | |
4727 | * Then release them. | |
4728 | */ | |
4729 | if (mapping->nrpages && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) { | |
4730 | err = filemap_write_and_wait_range(mapping, | |
4731 | offset, offset + length - 1); | |
4732 | ||
4733 | if (err) | |
4734 | return err; | |
4735 | } | |
4736 | ||
4737 | /* Now release the pages */ | |
4738 | if (last_page_offset > first_page_offset) { | |
4739 | truncate_inode_pages_range(mapping, first_page_offset, | |
4740 | last_page_offset-1); | |
4741 | } | |
4742 | ||
4743 | /* finish any pending end_io work */ | |
4744 | ext4_flush_completed_IO(inode); | |
4745 | ||
4746 | credits = ext4_writepage_trans_blocks(inode); | |
4747 | handle = ext4_journal_start(inode, credits); | |
4748 | if (IS_ERR(handle)) | |
4749 | return PTR_ERR(handle); | |
4750 | ||
4751 | err = ext4_orphan_add(handle, inode); | |
4752 | if (err) | |
4753 | goto out; | |
4754 | ||
4755 | /* | |
4756 | * Now we need to zero out the non-page-aligned data in the | |
4757 | * pages at the start and tail of the hole, and unmap the buffer | |
4758 | * heads for the block aligned regions of the page that were | |
4759 | * completely zeroed. | |
4760 | */ | |
4761 | if (first_page > last_page) { | |
4762 | /* | |
4763 | * If the file space being truncated is contained within a page | |
4764 | * just zero out and unmap the middle of that page | |
4765 | */ | |
4766 | err = ext4_discard_partial_page_buffers(handle, | |
4767 | mapping, offset, length, 0); | |
4768 | ||
4769 | if (err) | |
4770 | goto out; | |
4771 | } else { | |
4772 | /* | |
4773 | * zero out and unmap the partial page that contains | |
4774 | * the start of the hole | |
4775 | */ | |
4776 | page_len = first_page_offset - offset; | |
4777 | if (page_len > 0) { | |
4778 | err = ext4_discard_partial_page_buffers(handle, mapping, | |
4779 | offset, page_len, 0); | |
4780 | if (err) | |
4781 | goto out; | |
4782 | } | |
4783 | ||
4784 | /* | |
4785 | * zero out and unmap the partial page that contains | |
4786 | * the end of the hole | |
4787 | */ | |
4788 | page_len = offset + length - last_page_offset; | |
4789 | if (page_len > 0) { | |
4790 | err = ext4_discard_partial_page_buffers(handle, mapping, | |
4791 | last_page_offset, page_len, 0); | |
4792 | if (err) | |
4793 | goto out; | |
4794 | } | |
4795 | } | |
4796 | ||
4797 | ||
4798 | /* | |
4799 | * If i_size is contained in the last page, we need to | |
4800 | * unmap and zero the partial page after i_size | |
4801 | */ | |
4802 | if (inode->i_size >> PAGE_CACHE_SHIFT == last_page && | |
4803 | inode->i_size % PAGE_CACHE_SIZE != 0) { | |
4804 | ||
4805 | page_len = PAGE_CACHE_SIZE - | |
4806 | (inode->i_size & (PAGE_CACHE_SIZE - 1)); | |
4807 | ||
4808 | if (page_len > 0) { | |
4809 | err = ext4_discard_partial_page_buffers(handle, | |
4810 | mapping, inode->i_size, page_len, 0); | |
4811 | ||
4812 | if (err) | |
4813 | goto out; | |
4814 | } | |
4815 | } | |
4816 | ||
4817 | /* If there are no blocks to remove, return now */ | |
4818 | if (first_block >= last_block) | |
4819 | goto out; | |
4820 | ||
4821 | down_write(&EXT4_I(inode)->i_data_sem); | |
4822 | ext4_ext_invalidate_cache(inode); | |
4823 | ext4_discard_preallocations(inode); | |
4824 | ||
4825 | /* | |
4826 | * Loop over all the blocks and identify blocks | |
4827 | * that need to be punched out | |
4828 | */ | |
4829 | iblock = first_block; | |
4830 | blocks_released = 0; | |
4831 | while (iblock < last_block) { | |
4832 | max_blocks = last_block - iblock; | |
4833 | num_blocks = 1; | |
4834 | memset(&map, 0, sizeof(map)); | |
4835 | map.m_lblk = iblock; | |
4836 | map.m_len = max_blocks; | |
4837 | ret = ext4_ext_map_blocks(handle, inode, &map, | |
4838 | EXT4_GET_BLOCKS_PUNCH_OUT_EXT); | |
4839 | ||
4840 | if (ret > 0) { | |
4841 | blocks_released += ret; | |
4842 | num_blocks = ret; | |
4843 | } else if (ret == 0) { | |
4844 | /* | |
4845 | * If map blocks could not find the block, | |
4846 | * then it is in a hole. If the hole was | |
4847 | * not already cached, then map blocks should | |
4848 | * put it in the cache. So we can get the hole | |
4849 | * out of the cache | |
4850 | */ | |
4851 | memset(&cache_ex, 0, sizeof(cache_ex)); | |
4852 | if ((ext4_ext_check_cache(inode, iblock, &cache_ex)) && | |
4853 | !cache_ex.ec_start) { | |
4854 | ||
4855 | /* The hole is cached */ | |
4856 | num_blocks = cache_ex.ec_block + | |
4857 | cache_ex.ec_len - iblock; | |
4858 | ||
4859 | } else { | |
4860 | /* The block could not be identified */ | |
4861 | err = -EIO; | |
4862 | break; | |
4863 | } | |
4864 | } else { | |
4865 | /* Map blocks error */ | |
4866 | err = ret; | |
4867 | break; | |
4868 | } | |
4869 | ||
4870 | if (num_blocks == 0) { | |
4871 | /* This condition should never happen */ | |
4872 | ext_debug("Block lookup failed"); | |
4873 | err = -EIO; | |
4874 | break; | |
4875 | } | |
4876 | ||
4877 | iblock += num_blocks; | |
4878 | } | |
4879 | ||
4880 | if (blocks_released > 0) { | |
4881 | ext4_ext_invalidate_cache(inode); | |
4882 | ext4_discard_preallocations(inode); | |
4883 | } | |
4884 | ||
4885 | if (IS_SYNC(inode)) | |
4886 | ext4_handle_sync(handle); | |
4887 | ||
4888 | up_write(&EXT4_I(inode)->i_data_sem); | |
4889 | ||
4890 | out: | |
4891 | ext4_orphan_del(handle, inode); | |
4892 | inode->i_mtime = inode->i_ctime = ext4_current_time(inode); | |
4893 | ext4_mark_inode_dirty(handle, inode); | |
4894 | ext4_journal_stop(handle); | |
4895 | return err; | |
4896 | } | |
4897 | int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, | |
4898 | __u64 start, __u64 len) | |
4899 | { | |
4900 | ext4_lblk_t start_blk; | |
4901 | int error = 0; | |
4902 | ||
4903 | /* fallback to generic here if not in extents fmt */ | |
4904 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) | |
4905 | return generic_block_fiemap(inode, fieinfo, start, len, | |
4906 | ext4_get_block); | |
4907 | ||
4908 | if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS)) | |
4909 | return -EBADR; | |
4910 | ||
4911 | if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) { | |
4912 | error = ext4_xattr_fiemap(inode, fieinfo); | |
4913 | } else { | |
4914 | ext4_lblk_t len_blks; | |
4915 | __u64 last_blk; | |
4916 | ||
4917 | start_blk = start >> inode->i_sb->s_blocksize_bits; | |
4918 | last_blk = (start + len - 1) >> inode->i_sb->s_blocksize_bits; | |
4919 | if (last_blk >= EXT_MAX_BLOCKS) | |
4920 | last_blk = EXT_MAX_BLOCKS-1; | |
4921 | len_blks = ((ext4_lblk_t) last_blk) - start_blk + 1; | |
4922 | ||
4923 | /* | |
4924 | * Walk the extent tree gathering extent information. | |
4925 | * ext4_ext_fiemap_cb will push extents back to user. | |
4926 | */ | |
4927 | error = ext4_ext_walk_space(inode, start_blk, len_blks, | |
4928 | ext4_ext_fiemap_cb, fieinfo); | |
4929 | } | |
4930 | ||
4931 | return error; | |
4932 | } |