Commit | Line | Data |
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a86c6181 AT |
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/ext4_jbd2.h> | |
cd02ff0b | 36 | #include <linux/jbd2.h> |
a86c6181 AT |
37 | #include <linux/highuid.h> |
38 | #include <linux/pagemap.h> | |
39 | #include <linux/quotaops.h> | |
40 | #include <linux/string.h> | |
41 | #include <linux/slab.h> | |
a2df2a63 | 42 | #include <linux/falloc.h> |
a86c6181 AT |
43 | #include <linux/ext4_fs_extents.h> |
44 | #include <asm/uaccess.h> | |
45 | ||
46 | ||
d0d856e8 RD |
47 | /* |
48 | * ext_pblock: | |
49 | * combine low and high parts of physical block number into ext4_fsblk_t | |
50 | */ | |
09b88252 | 51 | static ext4_fsblk_t ext_pblock(struct ext4_extent *ex) |
f65e6fba AT |
52 | { |
53 | ext4_fsblk_t block; | |
54 | ||
b377611d | 55 | block = le32_to_cpu(ex->ee_start_lo); |
9b8f1f01 | 56 | block |= ((ext4_fsblk_t) le16_to_cpu(ex->ee_start_hi) << 31) << 1; |
f65e6fba AT |
57 | return block; |
58 | } | |
59 | ||
d0d856e8 RD |
60 | /* |
61 | * idx_pblock: | |
62 | * combine low and high parts of a leaf physical block number into ext4_fsblk_t | |
63 | */ | |
09b88252 | 64 | static ext4_fsblk_t idx_pblock(struct ext4_extent_idx *ix) |
f65e6fba AT |
65 | { |
66 | ext4_fsblk_t block; | |
67 | ||
d8dd0b45 | 68 | block = le32_to_cpu(ix->ei_leaf_lo); |
9b8f1f01 | 69 | block |= ((ext4_fsblk_t) le16_to_cpu(ix->ei_leaf_hi) << 31) << 1; |
f65e6fba AT |
70 | return block; |
71 | } | |
72 | ||
d0d856e8 RD |
73 | /* |
74 | * ext4_ext_store_pblock: | |
75 | * stores a large physical block number into an extent struct, | |
76 | * breaking it into parts | |
77 | */ | |
09b88252 | 78 | static void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb) |
f65e6fba | 79 | { |
b377611d | 80 | ex->ee_start_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff)); |
9b8f1f01 | 81 | ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff); |
f65e6fba AT |
82 | } |
83 | ||
d0d856e8 RD |
84 | /* |
85 | * ext4_idx_store_pblock: | |
86 | * stores a large physical block number into an index struct, | |
87 | * breaking it into parts | |
88 | */ | |
09b88252 | 89 | static void ext4_idx_store_pblock(struct ext4_extent_idx *ix, ext4_fsblk_t pb) |
f65e6fba | 90 | { |
d8dd0b45 | 91 | ix->ei_leaf_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff)); |
9b8f1f01 | 92 | ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff); |
f65e6fba AT |
93 | } |
94 | ||
a86c6181 AT |
95 | static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed) |
96 | { | |
97 | int err; | |
98 | ||
99 | if (handle->h_buffer_credits > needed) | |
100 | return handle; | |
101 | if (!ext4_journal_extend(handle, needed)) | |
102 | return handle; | |
103 | err = ext4_journal_restart(handle, needed); | |
104 | ||
105 | return handle; | |
106 | } | |
107 | ||
108 | /* | |
109 | * could return: | |
110 | * - EROFS | |
111 | * - ENOMEM | |
112 | */ | |
113 | static int ext4_ext_get_access(handle_t *handle, struct inode *inode, | |
114 | struct ext4_ext_path *path) | |
115 | { | |
116 | if (path->p_bh) { | |
117 | /* path points to block */ | |
118 | return ext4_journal_get_write_access(handle, path->p_bh); | |
119 | } | |
120 | /* path points to leaf/index in inode body */ | |
121 | /* we use in-core data, no need to protect them */ | |
122 | return 0; | |
123 | } | |
124 | ||
125 | /* | |
126 | * could return: | |
127 | * - EROFS | |
128 | * - ENOMEM | |
129 | * - EIO | |
130 | */ | |
131 | static int ext4_ext_dirty(handle_t *handle, struct inode *inode, | |
132 | struct ext4_ext_path *path) | |
133 | { | |
134 | int err; | |
135 | if (path->p_bh) { | |
136 | /* path points to block */ | |
137 | err = ext4_journal_dirty_metadata(handle, path->p_bh); | |
138 | } else { | |
139 | /* path points to leaf/index in inode body */ | |
140 | err = ext4_mark_inode_dirty(handle, inode); | |
141 | } | |
142 | return err; | |
143 | } | |
144 | ||
f65e6fba | 145 | static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode, |
a86c6181 | 146 | struct ext4_ext_path *path, |
725d26d3 | 147 | ext4_lblk_t block) |
a86c6181 AT |
148 | { |
149 | struct ext4_inode_info *ei = EXT4_I(inode); | |
f65e6fba AT |
150 | ext4_fsblk_t bg_start; |
151 | ext4_grpblk_t colour; | |
a86c6181 AT |
152 | int depth; |
153 | ||
154 | if (path) { | |
155 | struct ext4_extent *ex; | |
156 | depth = path->p_depth; | |
157 | ||
158 | /* try to predict block placement */ | |
7e028976 AM |
159 | ex = path[depth].p_ext; |
160 | if (ex) | |
f65e6fba | 161 | return ext_pblock(ex)+(block-le32_to_cpu(ex->ee_block)); |
a86c6181 | 162 | |
d0d856e8 RD |
163 | /* it looks like index is empty; |
164 | * try to find starting block from index itself */ | |
a86c6181 AT |
165 | if (path[depth].p_bh) |
166 | return path[depth].p_bh->b_blocknr; | |
167 | } | |
168 | ||
169 | /* OK. use inode's group */ | |
170 | bg_start = (ei->i_block_group * EXT4_BLOCKS_PER_GROUP(inode->i_sb)) + | |
171 | le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_first_data_block); | |
172 | colour = (current->pid % 16) * | |
173 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); | |
174 | return bg_start + colour + block; | |
175 | } | |
176 | ||
f65e6fba | 177 | static ext4_fsblk_t |
a86c6181 AT |
178 | ext4_ext_new_block(handle_t *handle, struct inode *inode, |
179 | struct ext4_ext_path *path, | |
180 | struct ext4_extent *ex, int *err) | |
181 | { | |
f65e6fba | 182 | ext4_fsblk_t goal, newblock; |
a86c6181 AT |
183 | |
184 | goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block)); | |
185 | newblock = ext4_new_block(handle, inode, goal, err); | |
186 | return newblock; | |
187 | } | |
188 | ||
09b88252 | 189 | static int ext4_ext_space_block(struct inode *inode) |
a86c6181 AT |
190 | { |
191 | int size; | |
192 | ||
193 | size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header)) | |
194 | / sizeof(struct ext4_extent); | |
bbf2f9fb | 195 | #ifdef AGGRESSIVE_TEST |
a86c6181 AT |
196 | if (size > 6) |
197 | size = 6; | |
198 | #endif | |
199 | return size; | |
200 | } | |
201 | ||
09b88252 | 202 | static int ext4_ext_space_block_idx(struct inode *inode) |
a86c6181 AT |
203 | { |
204 | int size; | |
205 | ||
206 | size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header)) | |
207 | / sizeof(struct ext4_extent_idx); | |
bbf2f9fb | 208 | #ifdef AGGRESSIVE_TEST |
a86c6181 AT |
209 | if (size > 5) |
210 | size = 5; | |
211 | #endif | |
212 | return size; | |
213 | } | |
214 | ||
09b88252 | 215 | static int ext4_ext_space_root(struct inode *inode) |
a86c6181 AT |
216 | { |
217 | int size; | |
218 | ||
219 | size = sizeof(EXT4_I(inode)->i_data); | |
220 | size -= sizeof(struct ext4_extent_header); | |
221 | size /= sizeof(struct ext4_extent); | |
bbf2f9fb | 222 | #ifdef AGGRESSIVE_TEST |
a86c6181 AT |
223 | if (size > 3) |
224 | size = 3; | |
225 | #endif | |
226 | return size; | |
227 | } | |
228 | ||
09b88252 | 229 | static int ext4_ext_space_root_idx(struct inode *inode) |
a86c6181 AT |
230 | { |
231 | int size; | |
232 | ||
233 | size = sizeof(EXT4_I(inode)->i_data); | |
234 | size -= sizeof(struct ext4_extent_header); | |
235 | size /= sizeof(struct ext4_extent_idx); | |
bbf2f9fb | 236 | #ifdef AGGRESSIVE_TEST |
a86c6181 AT |
237 | if (size > 4) |
238 | size = 4; | |
239 | #endif | |
240 | return size; | |
241 | } | |
242 | ||
c29c0ae7 AT |
243 | static int |
244 | ext4_ext_max_entries(struct inode *inode, int depth) | |
245 | { | |
246 | int max; | |
247 | ||
248 | if (depth == ext_depth(inode)) { | |
249 | if (depth == 0) | |
250 | max = ext4_ext_space_root(inode); | |
251 | else | |
252 | max = ext4_ext_space_root_idx(inode); | |
253 | } else { | |
254 | if (depth == 0) | |
255 | max = ext4_ext_space_block(inode); | |
256 | else | |
257 | max = ext4_ext_space_block_idx(inode); | |
258 | } | |
259 | ||
260 | return max; | |
261 | } | |
262 | ||
263 | static int __ext4_ext_check_header(const char *function, struct inode *inode, | |
264 | struct ext4_extent_header *eh, | |
265 | int depth) | |
266 | { | |
267 | const char *error_msg; | |
268 | int max = 0; | |
269 | ||
270 | if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) { | |
271 | error_msg = "invalid magic"; | |
272 | goto corrupted; | |
273 | } | |
274 | if (unlikely(le16_to_cpu(eh->eh_depth) != depth)) { | |
275 | error_msg = "unexpected eh_depth"; | |
276 | goto corrupted; | |
277 | } | |
278 | if (unlikely(eh->eh_max == 0)) { | |
279 | error_msg = "invalid eh_max"; | |
280 | goto corrupted; | |
281 | } | |
282 | max = ext4_ext_max_entries(inode, depth); | |
283 | if (unlikely(le16_to_cpu(eh->eh_max) > max)) { | |
284 | error_msg = "too large eh_max"; | |
285 | goto corrupted; | |
286 | } | |
287 | if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) { | |
288 | error_msg = "invalid eh_entries"; | |
289 | goto corrupted; | |
290 | } | |
291 | return 0; | |
292 | ||
293 | corrupted: | |
294 | ext4_error(inode->i_sb, function, | |
295 | "bad header in inode #%lu: %s - magic %x, " | |
296 | "entries %u, max %u(%u), depth %u(%u)", | |
297 | inode->i_ino, error_msg, le16_to_cpu(eh->eh_magic), | |
298 | le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max), | |
299 | max, le16_to_cpu(eh->eh_depth), depth); | |
300 | ||
301 | return -EIO; | |
302 | } | |
303 | ||
304 | #define ext4_ext_check_header(inode, eh, depth) \ | |
305 | __ext4_ext_check_header(__FUNCTION__, inode, eh, depth) | |
306 | ||
a86c6181 AT |
307 | #ifdef EXT_DEBUG |
308 | static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path) | |
309 | { | |
310 | int k, l = path->p_depth; | |
311 | ||
312 | ext_debug("path:"); | |
313 | for (k = 0; k <= l; k++, path++) { | |
314 | if (path->p_idx) { | |
2ae02107 | 315 | ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block), |
f65e6fba | 316 | idx_pblock(path->p_idx)); |
a86c6181 | 317 | } else if (path->p_ext) { |
2ae02107 | 318 | ext_debug(" %d:%d:%llu ", |
a86c6181 | 319 | le32_to_cpu(path->p_ext->ee_block), |
a2df2a63 | 320 | ext4_ext_get_actual_len(path->p_ext), |
f65e6fba | 321 | ext_pblock(path->p_ext)); |
a86c6181 AT |
322 | } else |
323 | ext_debug(" []"); | |
324 | } | |
325 | ext_debug("\n"); | |
326 | } | |
327 | ||
328 | static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path) | |
329 | { | |
330 | int depth = ext_depth(inode); | |
331 | struct ext4_extent_header *eh; | |
332 | struct ext4_extent *ex; | |
333 | int i; | |
334 | ||
335 | if (!path) | |
336 | return; | |
337 | ||
338 | eh = path[depth].p_hdr; | |
339 | ex = EXT_FIRST_EXTENT(eh); | |
340 | ||
341 | for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) { | |
2ae02107 | 342 | ext_debug("%d:%d:%llu ", le32_to_cpu(ex->ee_block), |
a2df2a63 | 343 | ext4_ext_get_actual_len(ex), ext_pblock(ex)); |
a86c6181 AT |
344 | } |
345 | ext_debug("\n"); | |
346 | } | |
347 | #else | |
348 | #define ext4_ext_show_path(inode,path) | |
349 | #define ext4_ext_show_leaf(inode,path) | |
350 | #endif | |
351 | ||
352 | static void ext4_ext_drop_refs(struct ext4_ext_path *path) | |
353 | { | |
354 | int depth = path->p_depth; | |
355 | int i; | |
356 | ||
357 | for (i = 0; i <= depth; i++, path++) | |
358 | if (path->p_bh) { | |
359 | brelse(path->p_bh); | |
360 | path->p_bh = NULL; | |
361 | } | |
362 | } | |
363 | ||
364 | /* | |
d0d856e8 RD |
365 | * ext4_ext_binsearch_idx: |
366 | * binary search for the closest index of the given block | |
c29c0ae7 | 367 | * the header must be checked before calling this |
a86c6181 AT |
368 | */ |
369 | static void | |
725d26d3 AK |
370 | ext4_ext_binsearch_idx(struct inode *inode, |
371 | struct ext4_ext_path *path, ext4_lblk_t block) | |
a86c6181 AT |
372 | { |
373 | struct ext4_extent_header *eh = path->p_hdr; | |
374 | struct ext4_extent_idx *r, *l, *m; | |
375 | ||
a86c6181 | 376 | |
bba90743 | 377 | ext_debug("binsearch for %u(idx): ", block); |
a86c6181 AT |
378 | |
379 | l = EXT_FIRST_INDEX(eh) + 1; | |
e9f410b1 | 380 | r = EXT_LAST_INDEX(eh); |
a86c6181 AT |
381 | while (l <= r) { |
382 | m = l + (r - l) / 2; | |
383 | if (block < le32_to_cpu(m->ei_block)) | |
384 | r = m - 1; | |
385 | else | |
386 | l = m + 1; | |
26d535ed DM |
387 | ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block), |
388 | m, le32_to_cpu(m->ei_block), | |
389 | r, le32_to_cpu(r->ei_block)); | |
a86c6181 AT |
390 | } |
391 | ||
392 | path->p_idx = l - 1; | |
f65e6fba | 393 | ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block), |
26d535ed | 394 | idx_pblock(path->p_idx)); |
a86c6181 AT |
395 | |
396 | #ifdef CHECK_BINSEARCH | |
397 | { | |
398 | struct ext4_extent_idx *chix, *ix; | |
399 | int k; | |
400 | ||
401 | chix = ix = EXT_FIRST_INDEX(eh); | |
402 | for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) { | |
403 | if (k != 0 && | |
404 | le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) { | |
405 | printk("k=%d, ix=0x%p, first=0x%p\n", k, | |
406 | ix, EXT_FIRST_INDEX(eh)); | |
407 | printk("%u <= %u\n", | |
408 | le32_to_cpu(ix->ei_block), | |
409 | le32_to_cpu(ix[-1].ei_block)); | |
410 | } | |
411 | BUG_ON(k && le32_to_cpu(ix->ei_block) | |
8c55e204 | 412 | <= le32_to_cpu(ix[-1].ei_block)); |
a86c6181 AT |
413 | if (block < le32_to_cpu(ix->ei_block)) |
414 | break; | |
415 | chix = ix; | |
416 | } | |
417 | BUG_ON(chix != path->p_idx); | |
418 | } | |
419 | #endif | |
420 | ||
421 | } | |
422 | ||
423 | /* | |
d0d856e8 RD |
424 | * ext4_ext_binsearch: |
425 | * binary search for closest extent of the given block | |
c29c0ae7 | 426 | * the header must be checked before calling this |
a86c6181 AT |
427 | */ |
428 | static void | |
725d26d3 AK |
429 | ext4_ext_binsearch(struct inode *inode, |
430 | struct ext4_ext_path *path, ext4_lblk_t block) | |
a86c6181 AT |
431 | { |
432 | struct ext4_extent_header *eh = path->p_hdr; | |
433 | struct ext4_extent *r, *l, *m; | |
434 | ||
a86c6181 AT |
435 | if (eh->eh_entries == 0) { |
436 | /* | |
d0d856e8 RD |
437 | * this leaf is empty: |
438 | * we get such a leaf in split/add case | |
a86c6181 AT |
439 | */ |
440 | return; | |
441 | } | |
442 | ||
bba90743 | 443 | ext_debug("binsearch for %u: ", block); |
a86c6181 AT |
444 | |
445 | l = EXT_FIRST_EXTENT(eh) + 1; | |
e9f410b1 | 446 | r = EXT_LAST_EXTENT(eh); |
a86c6181 AT |
447 | |
448 | while (l <= r) { | |
449 | m = l + (r - l) / 2; | |
450 | if (block < le32_to_cpu(m->ee_block)) | |
451 | r = m - 1; | |
452 | else | |
453 | l = m + 1; | |
26d535ed DM |
454 | ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block), |
455 | m, le32_to_cpu(m->ee_block), | |
456 | r, le32_to_cpu(r->ee_block)); | |
a86c6181 AT |
457 | } |
458 | ||
459 | path->p_ext = l - 1; | |
2ae02107 | 460 | ext_debug(" -> %d:%llu:%d ", |
8c55e204 DK |
461 | le32_to_cpu(path->p_ext->ee_block), |
462 | ext_pblock(path->p_ext), | |
a2df2a63 | 463 | ext4_ext_get_actual_len(path->p_ext)); |
a86c6181 AT |
464 | |
465 | #ifdef CHECK_BINSEARCH | |
466 | { | |
467 | struct ext4_extent *chex, *ex; | |
468 | int k; | |
469 | ||
470 | chex = ex = EXT_FIRST_EXTENT(eh); | |
471 | for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) { | |
472 | BUG_ON(k && le32_to_cpu(ex->ee_block) | |
8c55e204 | 473 | <= le32_to_cpu(ex[-1].ee_block)); |
a86c6181 AT |
474 | if (block < le32_to_cpu(ex->ee_block)) |
475 | break; | |
476 | chex = ex; | |
477 | } | |
478 | BUG_ON(chex != path->p_ext); | |
479 | } | |
480 | #endif | |
481 | ||
482 | } | |
483 | ||
484 | int ext4_ext_tree_init(handle_t *handle, struct inode *inode) | |
485 | { | |
486 | struct ext4_extent_header *eh; | |
487 | ||
488 | eh = ext_inode_hdr(inode); | |
489 | eh->eh_depth = 0; | |
490 | eh->eh_entries = 0; | |
491 | eh->eh_magic = EXT4_EXT_MAGIC; | |
492 | eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode)); | |
493 | ext4_mark_inode_dirty(handle, inode); | |
494 | ext4_ext_invalidate_cache(inode); | |
495 | return 0; | |
496 | } | |
497 | ||
498 | struct ext4_ext_path * | |
725d26d3 AK |
499 | ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block, |
500 | struct ext4_ext_path *path) | |
a86c6181 AT |
501 | { |
502 | struct ext4_extent_header *eh; | |
503 | struct buffer_head *bh; | |
504 | short int depth, i, ppos = 0, alloc = 0; | |
505 | ||
506 | eh = ext_inode_hdr(inode); | |
c29c0ae7 AT |
507 | depth = ext_depth(inode); |
508 | if (ext4_ext_check_header(inode, eh, depth)) | |
a86c6181 AT |
509 | return ERR_PTR(-EIO); |
510 | ||
a86c6181 AT |
511 | |
512 | /* account possible depth increase */ | |
513 | if (!path) { | |
5d4958f9 | 514 | path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 2), |
a86c6181 AT |
515 | GFP_NOFS); |
516 | if (!path) | |
517 | return ERR_PTR(-ENOMEM); | |
518 | alloc = 1; | |
519 | } | |
a86c6181 AT |
520 | path[0].p_hdr = eh; |
521 | ||
c29c0ae7 | 522 | i = depth; |
a86c6181 AT |
523 | /* walk through the tree */ |
524 | while (i) { | |
525 | ext_debug("depth %d: num %d, max %d\n", | |
526 | ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max)); | |
c29c0ae7 | 527 | |
a86c6181 | 528 | ext4_ext_binsearch_idx(inode, path + ppos, block); |
f65e6fba | 529 | path[ppos].p_block = idx_pblock(path[ppos].p_idx); |
a86c6181 AT |
530 | path[ppos].p_depth = i; |
531 | path[ppos].p_ext = NULL; | |
532 | ||
533 | bh = sb_bread(inode->i_sb, path[ppos].p_block); | |
534 | if (!bh) | |
535 | goto err; | |
536 | ||
537 | eh = ext_block_hdr(bh); | |
538 | ppos++; | |
539 | BUG_ON(ppos > depth); | |
540 | path[ppos].p_bh = bh; | |
541 | path[ppos].p_hdr = eh; | |
542 | i--; | |
543 | ||
c29c0ae7 | 544 | if (ext4_ext_check_header(inode, eh, i)) |
a86c6181 AT |
545 | goto err; |
546 | } | |
547 | ||
548 | path[ppos].p_depth = i; | |
549 | path[ppos].p_hdr = eh; | |
550 | path[ppos].p_ext = NULL; | |
551 | path[ppos].p_idx = NULL; | |
552 | ||
a86c6181 AT |
553 | /* find extent */ |
554 | ext4_ext_binsearch(inode, path + ppos, block); | |
555 | ||
556 | ext4_ext_show_path(inode, path); | |
557 | ||
558 | return path; | |
559 | ||
560 | err: | |
561 | ext4_ext_drop_refs(path); | |
562 | if (alloc) | |
563 | kfree(path); | |
564 | return ERR_PTR(-EIO); | |
565 | } | |
566 | ||
567 | /* | |
d0d856e8 RD |
568 | * ext4_ext_insert_index: |
569 | * insert new index [@logical;@ptr] into the block at @curp; | |
570 | * check where to insert: before @curp or after @curp | |
a86c6181 AT |
571 | */ |
572 | static int ext4_ext_insert_index(handle_t *handle, struct inode *inode, | |
573 | struct ext4_ext_path *curp, | |
f65e6fba | 574 | int logical, ext4_fsblk_t ptr) |
a86c6181 AT |
575 | { |
576 | struct ext4_extent_idx *ix; | |
577 | int len, err; | |
578 | ||
7e028976 AM |
579 | err = ext4_ext_get_access(handle, inode, curp); |
580 | if (err) | |
a86c6181 AT |
581 | return err; |
582 | ||
583 | BUG_ON(logical == le32_to_cpu(curp->p_idx->ei_block)); | |
584 | len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx; | |
585 | if (logical > le32_to_cpu(curp->p_idx->ei_block)) { | |
586 | /* insert after */ | |
587 | if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) { | |
588 | len = (len - 1) * sizeof(struct ext4_extent_idx); | |
589 | len = len < 0 ? 0 : len; | |
26d535ed | 590 | ext_debug("insert new index %d after: %llu. " |
a86c6181 AT |
591 | "move %d from 0x%p to 0x%p\n", |
592 | logical, ptr, len, | |
593 | (curp->p_idx + 1), (curp->p_idx + 2)); | |
594 | memmove(curp->p_idx + 2, curp->p_idx + 1, len); | |
595 | } | |
596 | ix = curp->p_idx + 1; | |
597 | } else { | |
598 | /* insert before */ | |
599 | len = len * sizeof(struct ext4_extent_idx); | |
600 | len = len < 0 ? 0 : len; | |
26d535ed | 601 | ext_debug("insert new index %d before: %llu. " |
a86c6181 AT |
602 | "move %d from 0x%p to 0x%p\n", |
603 | logical, ptr, len, | |
604 | curp->p_idx, (curp->p_idx + 1)); | |
605 | memmove(curp->p_idx + 1, curp->p_idx, len); | |
606 | ix = curp->p_idx; | |
607 | } | |
608 | ||
609 | ix->ei_block = cpu_to_le32(logical); | |
f65e6fba | 610 | ext4_idx_store_pblock(ix, ptr); |
a86c6181 AT |
611 | curp->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(curp->p_hdr->eh_entries)+1); |
612 | ||
613 | BUG_ON(le16_to_cpu(curp->p_hdr->eh_entries) | |
8c55e204 | 614 | > le16_to_cpu(curp->p_hdr->eh_max)); |
a86c6181 AT |
615 | BUG_ON(ix > EXT_LAST_INDEX(curp->p_hdr)); |
616 | ||
617 | err = ext4_ext_dirty(handle, inode, curp); | |
618 | ext4_std_error(inode->i_sb, err); | |
619 | ||
620 | return err; | |
621 | } | |
622 | ||
623 | /* | |
d0d856e8 RD |
624 | * ext4_ext_split: |
625 | * inserts new subtree into the path, using free index entry | |
626 | * at depth @at: | |
627 | * - allocates all needed blocks (new leaf and all intermediate index blocks) | |
628 | * - makes decision where to split | |
629 | * - moves remaining extents and index entries (right to the split point) | |
630 | * into the newly allocated blocks | |
631 | * - initializes subtree | |
a86c6181 AT |
632 | */ |
633 | static int ext4_ext_split(handle_t *handle, struct inode *inode, | |
634 | struct ext4_ext_path *path, | |
635 | struct ext4_extent *newext, int at) | |
636 | { | |
637 | struct buffer_head *bh = NULL; | |
638 | int depth = ext_depth(inode); | |
639 | struct ext4_extent_header *neh; | |
640 | struct ext4_extent_idx *fidx; | |
641 | struct ext4_extent *ex; | |
642 | int i = at, k, m, a; | |
f65e6fba | 643 | ext4_fsblk_t newblock, oldblock; |
a86c6181 | 644 | __le32 border; |
f65e6fba | 645 | ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */ |
a86c6181 AT |
646 | int err = 0; |
647 | ||
648 | /* make decision: where to split? */ | |
d0d856e8 | 649 | /* FIXME: now decision is simplest: at current extent */ |
a86c6181 | 650 | |
d0d856e8 | 651 | /* if current leaf will be split, then we should use |
a86c6181 AT |
652 | * border from split point */ |
653 | BUG_ON(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr)); | |
654 | if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) { | |
655 | border = path[depth].p_ext[1].ee_block; | |
d0d856e8 | 656 | ext_debug("leaf will be split." |
a86c6181 | 657 | " next leaf starts at %d\n", |
8c55e204 | 658 | le32_to_cpu(border)); |
a86c6181 AT |
659 | } else { |
660 | border = newext->ee_block; | |
661 | ext_debug("leaf will be added." | |
662 | " next leaf starts at %d\n", | |
8c55e204 | 663 | le32_to_cpu(border)); |
a86c6181 AT |
664 | } |
665 | ||
666 | /* | |
d0d856e8 RD |
667 | * If error occurs, then we break processing |
668 | * and mark filesystem read-only. index won't | |
a86c6181 | 669 | * be inserted and tree will be in consistent |
d0d856e8 | 670 | * state. Next mount will repair buffers too. |
a86c6181 AT |
671 | */ |
672 | ||
673 | /* | |
d0d856e8 RD |
674 | * Get array to track all allocated blocks. |
675 | * We need this to handle errors and free blocks | |
676 | * upon them. | |
a86c6181 | 677 | */ |
5d4958f9 | 678 | ablocks = kzalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS); |
a86c6181 AT |
679 | if (!ablocks) |
680 | return -ENOMEM; | |
a86c6181 AT |
681 | |
682 | /* allocate all needed blocks */ | |
683 | ext_debug("allocate %d blocks for indexes/leaf\n", depth - at); | |
684 | for (a = 0; a < depth - at; a++) { | |
685 | newblock = ext4_ext_new_block(handle, inode, path, newext, &err); | |
686 | if (newblock == 0) | |
687 | goto cleanup; | |
688 | ablocks[a] = newblock; | |
689 | } | |
690 | ||
691 | /* initialize new leaf */ | |
692 | newblock = ablocks[--a]; | |
693 | BUG_ON(newblock == 0); | |
694 | bh = sb_getblk(inode->i_sb, newblock); | |
695 | if (!bh) { | |
696 | err = -EIO; | |
697 | goto cleanup; | |
698 | } | |
699 | lock_buffer(bh); | |
700 | ||
7e028976 AM |
701 | err = ext4_journal_get_create_access(handle, bh); |
702 | if (err) | |
a86c6181 AT |
703 | goto cleanup; |
704 | ||
705 | neh = ext_block_hdr(bh); | |
706 | neh->eh_entries = 0; | |
707 | neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode)); | |
708 | neh->eh_magic = EXT4_EXT_MAGIC; | |
709 | neh->eh_depth = 0; | |
710 | ex = EXT_FIRST_EXTENT(neh); | |
711 | ||
d0d856e8 | 712 | /* move remainder of path[depth] to the new leaf */ |
a86c6181 AT |
713 | BUG_ON(path[depth].p_hdr->eh_entries != path[depth].p_hdr->eh_max); |
714 | /* start copy from next extent */ | |
715 | /* TODO: we could do it by single memmove */ | |
716 | m = 0; | |
717 | path[depth].p_ext++; | |
718 | while (path[depth].p_ext <= | |
719 | EXT_MAX_EXTENT(path[depth].p_hdr)) { | |
2ae02107 | 720 | ext_debug("move %d:%llu:%d in new leaf %llu\n", |
8c55e204 DK |
721 | le32_to_cpu(path[depth].p_ext->ee_block), |
722 | ext_pblock(path[depth].p_ext), | |
a2df2a63 | 723 | ext4_ext_get_actual_len(path[depth].p_ext), |
a86c6181 AT |
724 | newblock); |
725 | /*memmove(ex++, path[depth].p_ext++, | |
726 | sizeof(struct ext4_extent)); | |
727 | neh->eh_entries++;*/ | |
728 | path[depth].p_ext++; | |
729 | m++; | |
730 | } | |
731 | if (m) { | |
732 | memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m); | |
733 | neh->eh_entries = cpu_to_le16(le16_to_cpu(neh->eh_entries)+m); | |
734 | } | |
735 | ||
736 | set_buffer_uptodate(bh); | |
737 | unlock_buffer(bh); | |
738 | ||
7e028976 AM |
739 | err = ext4_journal_dirty_metadata(handle, bh); |
740 | if (err) | |
a86c6181 AT |
741 | goto cleanup; |
742 | brelse(bh); | |
743 | bh = NULL; | |
744 | ||
745 | /* correct old leaf */ | |
746 | if (m) { | |
7e028976 AM |
747 | err = ext4_ext_get_access(handle, inode, path + depth); |
748 | if (err) | |
a86c6181 AT |
749 | goto cleanup; |
750 | path[depth].p_hdr->eh_entries = | |
751 | cpu_to_le16(le16_to_cpu(path[depth].p_hdr->eh_entries)-m); | |
7e028976 AM |
752 | err = ext4_ext_dirty(handle, inode, path + depth); |
753 | if (err) | |
a86c6181 AT |
754 | goto cleanup; |
755 | ||
756 | } | |
757 | ||
758 | /* create intermediate indexes */ | |
759 | k = depth - at - 1; | |
760 | BUG_ON(k < 0); | |
761 | if (k) | |
762 | ext_debug("create %d intermediate indices\n", k); | |
763 | /* insert new index into current index block */ | |
764 | /* current depth stored in i var */ | |
765 | i = depth - 1; | |
766 | while (k--) { | |
767 | oldblock = newblock; | |
768 | newblock = ablocks[--a]; | |
bba90743 | 769 | bh = sb_getblk(inode->i_sb, newblock); |
a86c6181 AT |
770 | if (!bh) { |
771 | err = -EIO; | |
772 | goto cleanup; | |
773 | } | |
774 | lock_buffer(bh); | |
775 | ||
7e028976 AM |
776 | err = ext4_journal_get_create_access(handle, bh); |
777 | if (err) | |
a86c6181 AT |
778 | goto cleanup; |
779 | ||
780 | neh = ext_block_hdr(bh); | |
781 | neh->eh_entries = cpu_to_le16(1); | |
782 | neh->eh_magic = EXT4_EXT_MAGIC; | |
783 | neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode)); | |
784 | neh->eh_depth = cpu_to_le16(depth - i); | |
785 | fidx = EXT_FIRST_INDEX(neh); | |
786 | fidx->ei_block = border; | |
f65e6fba | 787 | ext4_idx_store_pblock(fidx, oldblock); |
a86c6181 | 788 | |
bba90743 ES |
789 | ext_debug("int.index at %d (block %llu): %u -> %llu\n", |
790 | i, newblock, le32_to_cpu(border), oldblock); | |
a86c6181 AT |
791 | /* copy indexes */ |
792 | m = 0; | |
793 | path[i].p_idx++; | |
794 | ||
795 | ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx, | |
796 | EXT_MAX_INDEX(path[i].p_hdr)); | |
797 | BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) != | |
798 | EXT_LAST_INDEX(path[i].p_hdr)); | |
799 | while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) { | |
26d535ed | 800 | ext_debug("%d: move %d:%llu in new index %llu\n", i, |
8c55e204 DK |
801 | le32_to_cpu(path[i].p_idx->ei_block), |
802 | idx_pblock(path[i].p_idx), | |
803 | newblock); | |
a86c6181 AT |
804 | /*memmove(++fidx, path[i].p_idx++, |
805 | sizeof(struct ext4_extent_idx)); | |
806 | neh->eh_entries++; | |
807 | BUG_ON(neh->eh_entries > neh->eh_max);*/ | |
808 | path[i].p_idx++; | |
809 | m++; | |
810 | } | |
811 | if (m) { | |
812 | memmove(++fidx, path[i].p_idx - m, | |
813 | sizeof(struct ext4_extent_idx) * m); | |
814 | neh->eh_entries = | |
815 | cpu_to_le16(le16_to_cpu(neh->eh_entries) + m); | |
816 | } | |
817 | set_buffer_uptodate(bh); | |
818 | unlock_buffer(bh); | |
819 | ||
7e028976 AM |
820 | err = ext4_journal_dirty_metadata(handle, bh); |
821 | if (err) | |
a86c6181 AT |
822 | goto cleanup; |
823 | brelse(bh); | |
824 | bh = NULL; | |
825 | ||
826 | /* correct old index */ | |
827 | if (m) { | |
828 | err = ext4_ext_get_access(handle, inode, path + i); | |
829 | if (err) | |
830 | goto cleanup; | |
831 | path[i].p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path[i].p_hdr->eh_entries)-m); | |
832 | err = ext4_ext_dirty(handle, inode, path + i); | |
833 | if (err) | |
834 | goto cleanup; | |
835 | } | |
836 | ||
837 | i--; | |
838 | } | |
839 | ||
840 | /* insert new index */ | |
a86c6181 AT |
841 | err = ext4_ext_insert_index(handle, inode, path + at, |
842 | le32_to_cpu(border), newblock); | |
843 | ||
844 | cleanup: | |
845 | if (bh) { | |
846 | if (buffer_locked(bh)) | |
847 | unlock_buffer(bh); | |
848 | brelse(bh); | |
849 | } | |
850 | ||
851 | if (err) { | |
852 | /* free all allocated blocks in error case */ | |
853 | for (i = 0; i < depth; i++) { | |
854 | if (!ablocks[i]) | |
855 | continue; | |
856 | ext4_free_blocks(handle, inode, ablocks[i], 1); | |
857 | } | |
858 | } | |
859 | kfree(ablocks); | |
860 | ||
861 | return err; | |
862 | } | |
863 | ||
864 | /* | |
d0d856e8 RD |
865 | * ext4_ext_grow_indepth: |
866 | * implements tree growing procedure: | |
867 | * - allocates new block | |
868 | * - moves top-level data (index block or leaf) into the new block | |
869 | * - initializes new top-level, creating index that points to the | |
870 | * just created block | |
a86c6181 AT |
871 | */ |
872 | static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode, | |
873 | struct ext4_ext_path *path, | |
874 | struct ext4_extent *newext) | |
875 | { | |
876 | struct ext4_ext_path *curp = path; | |
877 | struct ext4_extent_header *neh; | |
878 | struct ext4_extent_idx *fidx; | |
879 | struct buffer_head *bh; | |
f65e6fba | 880 | ext4_fsblk_t newblock; |
a86c6181 AT |
881 | int err = 0; |
882 | ||
883 | newblock = ext4_ext_new_block(handle, inode, path, newext, &err); | |
884 | if (newblock == 0) | |
885 | return err; | |
886 | ||
887 | bh = sb_getblk(inode->i_sb, newblock); | |
888 | if (!bh) { | |
889 | err = -EIO; | |
890 | ext4_std_error(inode->i_sb, err); | |
891 | return err; | |
892 | } | |
893 | lock_buffer(bh); | |
894 | ||
7e028976 AM |
895 | err = ext4_journal_get_create_access(handle, bh); |
896 | if (err) { | |
a86c6181 AT |
897 | unlock_buffer(bh); |
898 | goto out; | |
899 | } | |
900 | ||
901 | /* move top-level index/leaf into new block */ | |
902 | memmove(bh->b_data, curp->p_hdr, sizeof(EXT4_I(inode)->i_data)); | |
903 | ||
904 | /* set size of new block */ | |
905 | neh = ext_block_hdr(bh); | |
906 | /* old root could have indexes or leaves | |
907 | * so calculate e_max right way */ | |
908 | if (ext_depth(inode)) | |
909 | neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode)); | |
910 | else | |
911 | neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode)); | |
912 | neh->eh_magic = EXT4_EXT_MAGIC; | |
913 | set_buffer_uptodate(bh); | |
914 | unlock_buffer(bh); | |
915 | ||
7e028976 AM |
916 | err = ext4_journal_dirty_metadata(handle, bh); |
917 | if (err) | |
a86c6181 AT |
918 | goto out; |
919 | ||
920 | /* create index in new top-level index: num,max,pointer */ | |
7e028976 AM |
921 | err = ext4_ext_get_access(handle, inode, curp); |
922 | if (err) | |
a86c6181 AT |
923 | goto out; |
924 | ||
925 | curp->p_hdr->eh_magic = EXT4_EXT_MAGIC; | |
926 | curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode)); | |
927 | curp->p_hdr->eh_entries = cpu_to_le16(1); | |
928 | curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr); | |
e9f410b1 DM |
929 | |
930 | if (path[0].p_hdr->eh_depth) | |
931 | curp->p_idx->ei_block = | |
932 | EXT_FIRST_INDEX(path[0].p_hdr)->ei_block; | |
933 | else | |
934 | curp->p_idx->ei_block = | |
935 | EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block; | |
f65e6fba | 936 | ext4_idx_store_pblock(curp->p_idx, newblock); |
a86c6181 AT |
937 | |
938 | neh = ext_inode_hdr(inode); | |
939 | fidx = EXT_FIRST_INDEX(neh); | |
2ae02107 | 940 | ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n", |
a86c6181 | 941 | le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max), |
f65e6fba | 942 | le32_to_cpu(fidx->ei_block), idx_pblock(fidx)); |
a86c6181 AT |
943 | |
944 | neh->eh_depth = cpu_to_le16(path->p_depth + 1); | |
945 | err = ext4_ext_dirty(handle, inode, curp); | |
946 | out: | |
947 | brelse(bh); | |
948 | ||
949 | return err; | |
950 | } | |
951 | ||
952 | /* | |
d0d856e8 RD |
953 | * ext4_ext_create_new_leaf: |
954 | * finds empty index and adds new leaf. | |
955 | * if no free index is found, then it requests in-depth growing. | |
a86c6181 AT |
956 | */ |
957 | static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode, | |
958 | struct ext4_ext_path *path, | |
959 | struct ext4_extent *newext) | |
960 | { | |
961 | struct ext4_ext_path *curp; | |
962 | int depth, i, err = 0; | |
963 | ||
964 | repeat: | |
965 | i = depth = ext_depth(inode); | |
966 | ||
967 | /* walk up to the tree and look for free index entry */ | |
968 | curp = path + depth; | |
969 | while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) { | |
970 | i--; | |
971 | curp--; | |
972 | } | |
973 | ||
d0d856e8 RD |
974 | /* we use already allocated block for index block, |
975 | * so subsequent data blocks should be contiguous */ | |
a86c6181 AT |
976 | if (EXT_HAS_FREE_INDEX(curp)) { |
977 | /* if we found index with free entry, then use that | |
978 | * entry: create all needed subtree and add new leaf */ | |
979 | err = ext4_ext_split(handle, inode, path, newext, i); | |
980 | ||
981 | /* refill path */ | |
982 | ext4_ext_drop_refs(path); | |
983 | path = ext4_ext_find_extent(inode, | |
725d26d3 AK |
984 | (ext4_lblk_t)le32_to_cpu(newext->ee_block), |
985 | path); | |
a86c6181 AT |
986 | if (IS_ERR(path)) |
987 | err = PTR_ERR(path); | |
988 | } else { | |
989 | /* tree is full, time to grow in depth */ | |
990 | err = ext4_ext_grow_indepth(handle, inode, path, newext); | |
991 | if (err) | |
992 | goto out; | |
993 | ||
994 | /* refill path */ | |
995 | ext4_ext_drop_refs(path); | |
996 | path = ext4_ext_find_extent(inode, | |
725d26d3 AK |
997 | (ext4_lblk_t)le32_to_cpu(newext->ee_block), |
998 | path); | |
a86c6181 AT |
999 | if (IS_ERR(path)) { |
1000 | err = PTR_ERR(path); | |
1001 | goto out; | |
1002 | } | |
1003 | ||
1004 | /* | |
d0d856e8 RD |
1005 | * only first (depth 0 -> 1) produces free space; |
1006 | * in all other cases we have to split the grown tree | |
a86c6181 AT |
1007 | */ |
1008 | depth = ext_depth(inode); | |
1009 | if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) { | |
d0d856e8 | 1010 | /* now we need to split */ |
a86c6181 AT |
1011 | goto repeat; |
1012 | } | |
1013 | } | |
1014 | ||
1015 | out: | |
1016 | return err; | |
1017 | } | |
1018 | ||
1019 | /* | |
d0d856e8 RD |
1020 | * ext4_ext_next_allocated_block: |
1021 | * returns allocated block in subsequent extent or EXT_MAX_BLOCK. | |
1022 | * NOTE: it considers block number from index entry as | |
1023 | * allocated block. Thus, index entries have to be consistent | |
1024 | * with leaves. | |
a86c6181 | 1025 | */ |
725d26d3 | 1026 | static ext4_lblk_t |
a86c6181 AT |
1027 | ext4_ext_next_allocated_block(struct ext4_ext_path *path) |
1028 | { | |
1029 | int depth; | |
1030 | ||
1031 | BUG_ON(path == NULL); | |
1032 | depth = path->p_depth; | |
1033 | ||
1034 | if (depth == 0 && path->p_ext == NULL) | |
1035 | return EXT_MAX_BLOCK; | |
1036 | ||
1037 | while (depth >= 0) { | |
1038 | if (depth == path->p_depth) { | |
1039 | /* leaf */ | |
1040 | if (path[depth].p_ext != | |
1041 | EXT_LAST_EXTENT(path[depth].p_hdr)) | |
1042 | return le32_to_cpu(path[depth].p_ext[1].ee_block); | |
1043 | } else { | |
1044 | /* index */ | |
1045 | if (path[depth].p_idx != | |
1046 | EXT_LAST_INDEX(path[depth].p_hdr)) | |
1047 | return le32_to_cpu(path[depth].p_idx[1].ei_block); | |
1048 | } | |
1049 | depth--; | |
1050 | } | |
1051 | ||
1052 | return EXT_MAX_BLOCK; | |
1053 | } | |
1054 | ||
1055 | /* | |
d0d856e8 | 1056 | * ext4_ext_next_leaf_block: |
a86c6181 AT |
1057 | * returns first allocated block from next leaf or EXT_MAX_BLOCK |
1058 | */ | |
725d26d3 | 1059 | static ext4_lblk_t ext4_ext_next_leaf_block(struct inode *inode, |
63f57933 | 1060 | struct ext4_ext_path *path) |
a86c6181 AT |
1061 | { |
1062 | int depth; | |
1063 | ||
1064 | BUG_ON(path == NULL); | |
1065 | depth = path->p_depth; | |
1066 | ||
1067 | /* zero-tree has no leaf blocks at all */ | |
1068 | if (depth == 0) | |
1069 | return EXT_MAX_BLOCK; | |
1070 | ||
1071 | /* go to index block */ | |
1072 | depth--; | |
1073 | ||
1074 | while (depth >= 0) { | |
1075 | if (path[depth].p_idx != | |
1076 | EXT_LAST_INDEX(path[depth].p_hdr)) | |
725d26d3 AK |
1077 | return (ext4_lblk_t) |
1078 | le32_to_cpu(path[depth].p_idx[1].ei_block); | |
a86c6181 AT |
1079 | depth--; |
1080 | } | |
1081 | ||
1082 | return EXT_MAX_BLOCK; | |
1083 | } | |
1084 | ||
1085 | /* | |
d0d856e8 RD |
1086 | * ext4_ext_correct_indexes: |
1087 | * if leaf gets modified and modified extent is first in the leaf, | |
1088 | * then we have to correct all indexes above. | |
a86c6181 AT |
1089 | * TODO: do we need to correct tree in all cases? |
1090 | */ | |
1091 | int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode, | |
1092 | struct ext4_ext_path *path) | |
1093 | { | |
1094 | struct ext4_extent_header *eh; | |
1095 | int depth = ext_depth(inode); | |
1096 | struct ext4_extent *ex; | |
1097 | __le32 border; | |
1098 | int k, err = 0; | |
1099 | ||
1100 | eh = path[depth].p_hdr; | |
1101 | ex = path[depth].p_ext; | |
1102 | BUG_ON(ex == NULL); | |
1103 | BUG_ON(eh == NULL); | |
1104 | ||
1105 | if (depth == 0) { | |
1106 | /* there is no tree at all */ | |
1107 | return 0; | |
1108 | } | |
1109 | ||
1110 | if (ex != EXT_FIRST_EXTENT(eh)) { | |
1111 | /* we correct tree if first leaf got modified only */ | |
1112 | return 0; | |
1113 | } | |
1114 | ||
1115 | /* | |
d0d856e8 | 1116 | * TODO: we need correction if border is smaller than current one |
a86c6181 AT |
1117 | */ |
1118 | k = depth - 1; | |
1119 | border = path[depth].p_ext->ee_block; | |
7e028976 AM |
1120 | err = ext4_ext_get_access(handle, inode, path + k); |
1121 | if (err) | |
a86c6181 AT |
1122 | return err; |
1123 | path[k].p_idx->ei_block = border; | |
7e028976 AM |
1124 | err = ext4_ext_dirty(handle, inode, path + k); |
1125 | if (err) | |
a86c6181 AT |
1126 | return err; |
1127 | ||
1128 | while (k--) { | |
1129 | /* change all left-side indexes */ | |
1130 | if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr)) | |
1131 | break; | |
7e028976 AM |
1132 | err = ext4_ext_get_access(handle, inode, path + k); |
1133 | if (err) | |
a86c6181 AT |
1134 | break; |
1135 | path[k].p_idx->ei_block = border; | |
7e028976 AM |
1136 | err = ext4_ext_dirty(handle, inode, path + k); |
1137 | if (err) | |
a86c6181 AT |
1138 | break; |
1139 | } | |
1140 | ||
1141 | return err; | |
1142 | } | |
1143 | ||
09b88252 | 1144 | static int |
a86c6181 AT |
1145 | ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, |
1146 | struct ext4_extent *ex2) | |
1147 | { | |
749269fa | 1148 | unsigned short ext1_ee_len, ext2_ee_len, max_len; |
a2df2a63 AA |
1149 | |
1150 | /* | |
1151 | * Make sure that either both extents are uninitialized, or | |
1152 | * both are _not_. | |
1153 | */ | |
1154 | if (ext4_ext_is_uninitialized(ex1) ^ ext4_ext_is_uninitialized(ex2)) | |
1155 | return 0; | |
1156 | ||
749269fa AA |
1157 | if (ext4_ext_is_uninitialized(ex1)) |
1158 | max_len = EXT_UNINIT_MAX_LEN; | |
1159 | else | |
1160 | max_len = EXT_INIT_MAX_LEN; | |
1161 | ||
a2df2a63 AA |
1162 | ext1_ee_len = ext4_ext_get_actual_len(ex1); |
1163 | ext2_ee_len = ext4_ext_get_actual_len(ex2); | |
1164 | ||
1165 | if (le32_to_cpu(ex1->ee_block) + ext1_ee_len != | |
63f57933 | 1166 | le32_to_cpu(ex2->ee_block)) |
a86c6181 AT |
1167 | return 0; |
1168 | ||
471d4011 SB |
1169 | /* |
1170 | * To allow future support for preallocated extents to be added | |
1171 | * as an RO_COMPAT feature, refuse to merge to extents if | |
d0d856e8 | 1172 | * this can result in the top bit of ee_len being set. |
471d4011 | 1173 | */ |
749269fa | 1174 | if (ext1_ee_len + ext2_ee_len > max_len) |
471d4011 | 1175 | return 0; |
bbf2f9fb | 1176 | #ifdef AGGRESSIVE_TEST |
a86c6181 AT |
1177 | if (le16_to_cpu(ex1->ee_len) >= 4) |
1178 | return 0; | |
1179 | #endif | |
1180 | ||
a2df2a63 | 1181 | if (ext_pblock(ex1) + ext1_ee_len == ext_pblock(ex2)) |
a86c6181 AT |
1182 | return 1; |
1183 | return 0; | |
1184 | } | |
1185 | ||
56055d3a AA |
1186 | /* |
1187 | * This function tries to merge the "ex" extent to the next extent in the tree. | |
1188 | * It always tries to merge towards right. If you want to merge towards | |
1189 | * left, pass "ex - 1" as argument instead of "ex". | |
1190 | * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns | |
1191 | * 1 if they got merged. | |
1192 | */ | |
1193 | int ext4_ext_try_to_merge(struct inode *inode, | |
1194 | struct ext4_ext_path *path, | |
1195 | struct ext4_extent *ex) | |
1196 | { | |
1197 | struct ext4_extent_header *eh; | |
1198 | unsigned int depth, len; | |
1199 | int merge_done = 0; | |
1200 | int uninitialized = 0; | |
1201 | ||
1202 | depth = ext_depth(inode); | |
1203 | BUG_ON(path[depth].p_hdr == NULL); | |
1204 | eh = path[depth].p_hdr; | |
1205 | ||
1206 | while (ex < EXT_LAST_EXTENT(eh)) { | |
1207 | if (!ext4_can_extents_be_merged(inode, ex, ex + 1)) | |
1208 | break; | |
1209 | /* merge with next extent! */ | |
1210 | if (ext4_ext_is_uninitialized(ex)) | |
1211 | uninitialized = 1; | |
1212 | ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex) | |
1213 | + ext4_ext_get_actual_len(ex + 1)); | |
1214 | if (uninitialized) | |
1215 | ext4_ext_mark_uninitialized(ex); | |
1216 | ||
1217 | if (ex + 1 < EXT_LAST_EXTENT(eh)) { | |
1218 | len = (EXT_LAST_EXTENT(eh) - ex - 1) | |
1219 | * sizeof(struct ext4_extent); | |
1220 | memmove(ex + 1, ex + 2, len); | |
1221 | } | |
1222 | eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries) - 1); | |
1223 | merge_done = 1; | |
1224 | WARN_ON(eh->eh_entries == 0); | |
1225 | if (!eh->eh_entries) | |
1226 | ext4_error(inode->i_sb, "ext4_ext_try_to_merge", | |
1227 | "inode#%lu, eh->eh_entries = 0!", inode->i_ino); | |
1228 | } | |
1229 | ||
1230 | return merge_done; | |
1231 | } | |
1232 | ||
25d14f98 AA |
1233 | /* |
1234 | * check if a portion of the "newext" extent overlaps with an | |
1235 | * existing extent. | |
1236 | * | |
1237 | * If there is an overlap discovered, it updates the length of the newext | |
1238 | * such that there will be no overlap, and then returns 1. | |
1239 | * If there is no overlap found, it returns 0. | |
1240 | */ | |
1241 | unsigned int ext4_ext_check_overlap(struct inode *inode, | |
1242 | struct ext4_extent *newext, | |
1243 | struct ext4_ext_path *path) | |
1244 | { | |
725d26d3 | 1245 | ext4_lblk_t b1, b2; |
25d14f98 AA |
1246 | unsigned int depth, len1; |
1247 | unsigned int ret = 0; | |
1248 | ||
1249 | b1 = le32_to_cpu(newext->ee_block); | |
a2df2a63 | 1250 | len1 = ext4_ext_get_actual_len(newext); |
25d14f98 AA |
1251 | depth = ext_depth(inode); |
1252 | if (!path[depth].p_ext) | |
1253 | goto out; | |
1254 | b2 = le32_to_cpu(path[depth].p_ext->ee_block); | |
1255 | ||
1256 | /* | |
1257 | * get the next allocated block if the extent in the path | |
1258 | * is before the requested block(s) | |
1259 | */ | |
1260 | if (b2 < b1) { | |
1261 | b2 = ext4_ext_next_allocated_block(path); | |
1262 | if (b2 == EXT_MAX_BLOCK) | |
1263 | goto out; | |
1264 | } | |
1265 | ||
725d26d3 | 1266 | /* check for wrap through zero on extent logical start block*/ |
25d14f98 AA |
1267 | if (b1 + len1 < b1) { |
1268 | len1 = EXT_MAX_BLOCK - b1; | |
1269 | newext->ee_len = cpu_to_le16(len1); | |
1270 | ret = 1; | |
1271 | } | |
1272 | ||
1273 | /* check for overlap */ | |
1274 | if (b1 + len1 > b2) { | |
1275 | newext->ee_len = cpu_to_le16(b2 - b1); | |
1276 | ret = 1; | |
1277 | } | |
1278 | out: | |
1279 | return ret; | |
1280 | } | |
1281 | ||
a86c6181 | 1282 | /* |
d0d856e8 RD |
1283 | * ext4_ext_insert_extent: |
1284 | * tries to merge requsted extent into the existing extent or | |
1285 | * inserts requested extent as new one into the tree, | |
1286 | * creating new leaf in the no-space case. | |
a86c6181 AT |
1287 | */ |
1288 | int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, | |
1289 | struct ext4_ext_path *path, | |
1290 | struct ext4_extent *newext) | |
1291 | { | |
1292 | struct ext4_extent_header * eh; | |
1293 | struct ext4_extent *ex, *fex; | |
1294 | struct ext4_extent *nearex; /* nearest extent */ | |
1295 | struct ext4_ext_path *npath = NULL; | |
725d26d3 AK |
1296 | int depth, len, err; |
1297 | ext4_lblk_t next; | |
a2df2a63 | 1298 | unsigned uninitialized = 0; |
a86c6181 | 1299 | |
a2df2a63 | 1300 | BUG_ON(ext4_ext_get_actual_len(newext) == 0); |
a86c6181 AT |
1301 | depth = ext_depth(inode); |
1302 | ex = path[depth].p_ext; | |
1303 | BUG_ON(path[depth].p_hdr == NULL); | |
1304 | ||
1305 | /* try to insert block into found extent and return */ | |
1306 | if (ex && ext4_can_extents_be_merged(inode, ex, newext)) { | |
2ae02107 | 1307 | ext_debug("append %d block to %d:%d (from %llu)\n", |
a2df2a63 | 1308 | ext4_ext_get_actual_len(newext), |
a86c6181 | 1309 | le32_to_cpu(ex->ee_block), |
a2df2a63 | 1310 | ext4_ext_get_actual_len(ex), ext_pblock(ex)); |
7e028976 AM |
1311 | err = ext4_ext_get_access(handle, inode, path + depth); |
1312 | if (err) | |
a86c6181 | 1313 | return err; |
a2df2a63 AA |
1314 | |
1315 | /* | |
1316 | * ext4_can_extents_be_merged should have checked that either | |
1317 | * both extents are uninitialized, or both aren't. Thus we | |
1318 | * need to check only one of them here. | |
1319 | */ | |
1320 | if (ext4_ext_is_uninitialized(ex)) | |
1321 | uninitialized = 1; | |
1322 | ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex) | |
1323 | + ext4_ext_get_actual_len(newext)); | |
1324 | if (uninitialized) | |
1325 | ext4_ext_mark_uninitialized(ex); | |
a86c6181 AT |
1326 | eh = path[depth].p_hdr; |
1327 | nearex = ex; | |
1328 | goto merge; | |
1329 | } | |
1330 | ||
1331 | repeat: | |
1332 | depth = ext_depth(inode); | |
1333 | eh = path[depth].p_hdr; | |
1334 | if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) | |
1335 | goto has_space; | |
1336 | ||
1337 | /* probably next leaf has space for us? */ | |
1338 | fex = EXT_LAST_EXTENT(eh); | |
1339 | next = ext4_ext_next_leaf_block(inode, path); | |
1340 | if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block) | |
1341 | && next != EXT_MAX_BLOCK) { | |
1342 | ext_debug("next leaf block - %d\n", next); | |
1343 | BUG_ON(npath != NULL); | |
1344 | npath = ext4_ext_find_extent(inode, next, NULL); | |
1345 | if (IS_ERR(npath)) | |
1346 | return PTR_ERR(npath); | |
1347 | BUG_ON(npath->p_depth != path->p_depth); | |
1348 | eh = npath[depth].p_hdr; | |
1349 | if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) { | |
1350 | ext_debug("next leaf isnt full(%d)\n", | |
1351 | le16_to_cpu(eh->eh_entries)); | |
1352 | path = npath; | |
1353 | goto repeat; | |
1354 | } | |
1355 | ext_debug("next leaf has no free space(%d,%d)\n", | |
1356 | le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max)); | |
1357 | } | |
1358 | ||
1359 | /* | |
d0d856e8 RD |
1360 | * There is no free space in the found leaf. |
1361 | * We're gonna add a new leaf in the tree. | |
a86c6181 AT |
1362 | */ |
1363 | err = ext4_ext_create_new_leaf(handle, inode, path, newext); | |
1364 | if (err) | |
1365 | goto cleanup; | |
1366 | depth = ext_depth(inode); | |
1367 | eh = path[depth].p_hdr; | |
1368 | ||
1369 | has_space: | |
1370 | nearex = path[depth].p_ext; | |
1371 | ||
7e028976 AM |
1372 | err = ext4_ext_get_access(handle, inode, path + depth); |
1373 | if (err) | |
a86c6181 AT |
1374 | goto cleanup; |
1375 | ||
1376 | if (!nearex) { | |
1377 | /* there is no extent in this leaf, create first one */ | |
2ae02107 | 1378 | ext_debug("first extent in the leaf: %d:%llu:%d\n", |
8c55e204 DK |
1379 | le32_to_cpu(newext->ee_block), |
1380 | ext_pblock(newext), | |
a2df2a63 | 1381 | ext4_ext_get_actual_len(newext)); |
a86c6181 AT |
1382 | path[depth].p_ext = EXT_FIRST_EXTENT(eh); |
1383 | } else if (le32_to_cpu(newext->ee_block) | |
8c55e204 | 1384 | > le32_to_cpu(nearex->ee_block)) { |
a86c6181 AT |
1385 | /* BUG_ON(newext->ee_block == nearex->ee_block); */ |
1386 | if (nearex != EXT_LAST_EXTENT(eh)) { | |
1387 | len = EXT_MAX_EXTENT(eh) - nearex; | |
1388 | len = (len - 1) * sizeof(struct ext4_extent); | |
1389 | len = len < 0 ? 0 : len; | |
2ae02107 | 1390 | ext_debug("insert %d:%llu:%d after: nearest 0x%p, " |
a86c6181 | 1391 | "move %d from 0x%p to 0x%p\n", |
8c55e204 DK |
1392 | le32_to_cpu(newext->ee_block), |
1393 | ext_pblock(newext), | |
a2df2a63 | 1394 | ext4_ext_get_actual_len(newext), |
a86c6181 AT |
1395 | nearex, len, nearex + 1, nearex + 2); |
1396 | memmove(nearex + 2, nearex + 1, len); | |
1397 | } | |
1398 | path[depth].p_ext = nearex + 1; | |
1399 | } else { | |
1400 | BUG_ON(newext->ee_block == nearex->ee_block); | |
1401 | len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent); | |
1402 | len = len < 0 ? 0 : len; | |
2ae02107 | 1403 | ext_debug("insert %d:%llu:%d before: nearest 0x%p, " |
a86c6181 AT |
1404 | "move %d from 0x%p to 0x%p\n", |
1405 | le32_to_cpu(newext->ee_block), | |
f65e6fba | 1406 | ext_pblock(newext), |
a2df2a63 | 1407 | ext4_ext_get_actual_len(newext), |
a86c6181 AT |
1408 | nearex, len, nearex + 1, nearex + 2); |
1409 | memmove(nearex + 1, nearex, len); | |
1410 | path[depth].p_ext = nearex; | |
1411 | } | |
1412 | ||
1413 | eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)+1); | |
1414 | nearex = path[depth].p_ext; | |
1415 | nearex->ee_block = newext->ee_block; | |
b377611d | 1416 | ext4_ext_store_pblock(nearex, ext_pblock(newext)); |
a86c6181 | 1417 | nearex->ee_len = newext->ee_len; |
a86c6181 AT |
1418 | |
1419 | merge: | |
1420 | /* try to merge extents to the right */ | |
56055d3a | 1421 | ext4_ext_try_to_merge(inode, path, nearex); |
a86c6181 AT |
1422 | |
1423 | /* try to merge extents to the left */ | |
1424 | ||
1425 | /* time to correct all indexes above */ | |
1426 | err = ext4_ext_correct_indexes(handle, inode, path); | |
1427 | if (err) | |
1428 | goto cleanup; | |
1429 | ||
1430 | err = ext4_ext_dirty(handle, inode, path + depth); | |
1431 | ||
1432 | cleanup: | |
1433 | if (npath) { | |
1434 | ext4_ext_drop_refs(npath); | |
1435 | kfree(npath); | |
1436 | } | |
1437 | ext4_ext_tree_changed(inode); | |
1438 | ext4_ext_invalidate_cache(inode); | |
1439 | return err; | |
1440 | } | |
1441 | ||
09b88252 | 1442 | static void |
725d26d3 | 1443 | ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block, |
dd54567a | 1444 | __u32 len, ext4_fsblk_t start, int type) |
a86c6181 AT |
1445 | { |
1446 | struct ext4_ext_cache *cex; | |
1447 | BUG_ON(len == 0); | |
1448 | cex = &EXT4_I(inode)->i_cached_extent; | |
1449 | cex->ec_type = type; | |
1450 | cex->ec_block = block; | |
1451 | cex->ec_len = len; | |
1452 | cex->ec_start = start; | |
1453 | } | |
1454 | ||
1455 | /* | |
d0d856e8 RD |
1456 | * ext4_ext_put_gap_in_cache: |
1457 | * calculate boundaries of the gap that the requested block fits into | |
a86c6181 AT |
1458 | * and cache this gap |
1459 | */ | |
09b88252 | 1460 | static void |
a86c6181 | 1461 | ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path, |
725d26d3 | 1462 | ext4_lblk_t block) |
a86c6181 AT |
1463 | { |
1464 | int depth = ext_depth(inode); | |
725d26d3 AK |
1465 | unsigned long len; |
1466 | ext4_lblk_t lblock; | |
a86c6181 AT |
1467 | struct ext4_extent *ex; |
1468 | ||
1469 | ex = path[depth].p_ext; | |
1470 | if (ex == NULL) { | |
1471 | /* there is no extent yet, so gap is [0;-] */ | |
1472 | lblock = 0; | |
1473 | len = EXT_MAX_BLOCK; | |
1474 | ext_debug("cache gap(whole file):"); | |
1475 | } else if (block < le32_to_cpu(ex->ee_block)) { | |
1476 | lblock = block; | |
1477 | len = le32_to_cpu(ex->ee_block) - block; | |
bba90743 ES |
1478 | ext_debug("cache gap(before): %u [%u:%u]", |
1479 | block, | |
1480 | le32_to_cpu(ex->ee_block), | |
1481 | ext4_ext_get_actual_len(ex)); | |
a86c6181 | 1482 | } else if (block >= le32_to_cpu(ex->ee_block) |
a2df2a63 | 1483 | + ext4_ext_get_actual_len(ex)) { |
725d26d3 | 1484 | ext4_lblk_t next; |
8c55e204 | 1485 | lblock = le32_to_cpu(ex->ee_block) |
a2df2a63 | 1486 | + ext4_ext_get_actual_len(ex); |
725d26d3 AK |
1487 | |
1488 | next = ext4_ext_next_allocated_block(path); | |
bba90743 ES |
1489 | ext_debug("cache gap(after): [%u:%u] %u", |
1490 | le32_to_cpu(ex->ee_block), | |
1491 | ext4_ext_get_actual_len(ex), | |
1492 | block); | |
725d26d3 AK |
1493 | BUG_ON(next == lblock); |
1494 | len = next - lblock; | |
a86c6181 AT |
1495 | } else { |
1496 | lblock = len = 0; | |
1497 | BUG(); | |
1498 | } | |
1499 | ||
bba90743 | 1500 | ext_debug(" -> %u:%lu\n", lblock, len); |
a86c6181 AT |
1501 | ext4_ext_put_in_cache(inode, lblock, len, 0, EXT4_EXT_CACHE_GAP); |
1502 | } | |
1503 | ||
09b88252 | 1504 | static int |
725d26d3 | 1505 | ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block, |
a86c6181 AT |
1506 | struct ext4_extent *ex) |
1507 | { | |
1508 | struct ext4_ext_cache *cex; | |
1509 | ||
1510 | cex = &EXT4_I(inode)->i_cached_extent; | |
1511 | ||
1512 | /* has cache valid data? */ | |
1513 | if (cex->ec_type == EXT4_EXT_CACHE_NO) | |
1514 | return EXT4_EXT_CACHE_NO; | |
1515 | ||
1516 | BUG_ON(cex->ec_type != EXT4_EXT_CACHE_GAP && | |
1517 | cex->ec_type != EXT4_EXT_CACHE_EXTENT); | |
1518 | if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) { | |
8c55e204 | 1519 | ex->ee_block = cpu_to_le32(cex->ec_block); |
f65e6fba | 1520 | ext4_ext_store_pblock(ex, cex->ec_start); |
8c55e204 | 1521 | ex->ee_len = cpu_to_le16(cex->ec_len); |
bba90743 ES |
1522 | ext_debug("%u cached by %u:%u:%llu\n", |
1523 | block, | |
1524 | cex->ec_block, cex->ec_len, cex->ec_start); | |
a86c6181 AT |
1525 | return cex->ec_type; |
1526 | } | |
1527 | ||
1528 | /* not in cache */ | |
1529 | return EXT4_EXT_CACHE_NO; | |
1530 | } | |
1531 | ||
1532 | /* | |
d0d856e8 RD |
1533 | * ext4_ext_rm_idx: |
1534 | * removes index from the index block. | |
1535 | * It's used in truncate case only, thus all requests are for | |
1536 | * last index in the block only. | |
a86c6181 AT |
1537 | */ |
1538 | int ext4_ext_rm_idx(handle_t *handle, struct inode *inode, | |
1539 | struct ext4_ext_path *path) | |
1540 | { | |
1541 | struct buffer_head *bh; | |
1542 | int err; | |
f65e6fba | 1543 | ext4_fsblk_t leaf; |
a86c6181 AT |
1544 | |
1545 | /* free index block */ | |
1546 | path--; | |
f65e6fba | 1547 | leaf = idx_pblock(path->p_idx); |
a86c6181 | 1548 | BUG_ON(path->p_hdr->eh_entries == 0); |
7e028976 AM |
1549 | err = ext4_ext_get_access(handle, inode, path); |
1550 | if (err) | |
a86c6181 AT |
1551 | return err; |
1552 | path->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path->p_hdr->eh_entries)-1); | |
7e028976 AM |
1553 | err = ext4_ext_dirty(handle, inode, path); |
1554 | if (err) | |
a86c6181 | 1555 | return err; |
2ae02107 | 1556 | ext_debug("index is empty, remove it, free block %llu\n", leaf); |
a86c6181 AT |
1557 | bh = sb_find_get_block(inode->i_sb, leaf); |
1558 | ext4_forget(handle, 1, inode, bh, leaf); | |
1559 | ext4_free_blocks(handle, inode, leaf, 1); | |
1560 | return err; | |
1561 | } | |
1562 | ||
1563 | /* | |
d0d856e8 RD |
1564 | * ext4_ext_calc_credits_for_insert: |
1565 | * This routine returns max. credits that the extent tree can consume. | |
a86c6181 | 1566 | * It should be OK for low-performance paths like ->writepage() |
d0d856e8 RD |
1567 | * To allow many writing processes to fit into a single transaction, |
1568 | * the caller should calculate credits under truncate_mutex and | |
1569 | * pass the actual path. | |
a86c6181 | 1570 | */ |
09b88252 | 1571 | int ext4_ext_calc_credits_for_insert(struct inode *inode, |
a86c6181 AT |
1572 | struct ext4_ext_path *path) |
1573 | { | |
1574 | int depth, needed; | |
1575 | ||
1576 | if (path) { | |
1577 | /* probably there is space in leaf? */ | |
1578 | depth = ext_depth(inode); | |
1579 | if (le16_to_cpu(path[depth].p_hdr->eh_entries) | |
1580 | < le16_to_cpu(path[depth].p_hdr->eh_max)) | |
1581 | return 1; | |
1582 | } | |
1583 | ||
1584 | /* | |
d0d856e8 | 1585 | * given 32-bit logical block (4294967296 blocks), max. tree |
a86c6181 | 1586 | * can be 4 levels in depth -- 4 * 340^4 == 53453440000. |
d0d856e8 | 1587 | * Let's also add one more level for imbalance. |
a86c6181 AT |
1588 | */ |
1589 | depth = 5; | |
1590 | ||
1591 | /* allocation of new data block(s) */ | |
1592 | needed = 2; | |
1593 | ||
1594 | /* | |
d0d856e8 | 1595 | * tree can be full, so it would need to grow in depth: |
feb18927 JL |
1596 | * we need one credit to modify old root, credits for |
1597 | * new root will be added in split accounting | |
a86c6181 | 1598 | */ |
feb18927 | 1599 | needed += 1; |
a86c6181 AT |
1600 | |
1601 | /* | |
d0d856e8 | 1602 | * Index split can happen, we would need: |
a86c6181 AT |
1603 | * allocate intermediate indexes (bitmap + group) |
1604 | * + change two blocks at each level, but root (already included) | |
1605 | */ | |
feb18927 | 1606 | needed += (depth * 2) + (depth * 2); |
a86c6181 AT |
1607 | |
1608 | /* any allocation modifies superblock */ | |
1609 | needed += 1; | |
1610 | ||
1611 | return needed; | |
1612 | } | |
1613 | ||
1614 | static int ext4_remove_blocks(handle_t *handle, struct inode *inode, | |
1615 | struct ext4_extent *ex, | |
725d26d3 | 1616 | ext4_lblk_t from, ext4_lblk_t to) |
a86c6181 AT |
1617 | { |
1618 | struct buffer_head *bh; | |
a2df2a63 | 1619 | unsigned short ee_len = ext4_ext_get_actual_len(ex); |
a86c6181 AT |
1620 | int i; |
1621 | ||
1622 | #ifdef EXTENTS_STATS | |
1623 | { | |
1624 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
a86c6181 AT |
1625 | spin_lock(&sbi->s_ext_stats_lock); |
1626 | sbi->s_ext_blocks += ee_len; | |
1627 | sbi->s_ext_extents++; | |
1628 | if (ee_len < sbi->s_ext_min) | |
1629 | sbi->s_ext_min = ee_len; | |
1630 | if (ee_len > sbi->s_ext_max) | |
1631 | sbi->s_ext_max = ee_len; | |
1632 | if (ext_depth(inode) > sbi->s_depth_max) | |
1633 | sbi->s_depth_max = ext_depth(inode); | |
1634 | spin_unlock(&sbi->s_ext_stats_lock); | |
1635 | } | |
1636 | #endif | |
1637 | if (from >= le32_to_cpu(ex->ee_block) | |
a2df2a63 | 1638 | && to == le32_to_cpu(ex->ee_block) + ee_len - 1) { |
a86c6181 | 1639 | /* tail removal */ |
725d26d3 | 1640 | ext4_lblk_t num; |
f65e6fba | 1641 | ext4_fsblk_t start; |
725d26d3 | 1642 | |
a2df2a63 AA |
1643 | num = le32_to_cpu(ex->ee_block) + ee_len - from; |
1644 | start = ext_pblock(ex) + ee_len - num; | |
725d26d3 | 1645 | ext_debug("free last %u blocks starting %llu\n", num, start); |
a86c6181 AT |
1646 | for (i = 0; i < num; i++) { |
1647 | bh = sb_find_get_block(inode->i_sb, start + i); | |
1648 | ext4_forget(handle, 0, inode, bh, start + i); | |
1649 | } | |
1650 | ext4_free_blocks(handle, inode, start, num); | |
1651 | } else if (from == le32_to_cpu(ex->ee_block) | |
a2df2a63 | 1652 | && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) { |
725d26d3 | 1653 | printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n", |
a2df2a63 | 1654 | from, to, le32_to_cpu(ex->ee_block), ee_len); |
a86c6181 | 1655 | } else { |
725d26d3 AK |
1656 | printk(KERN_INFO "strange request: removal(2) " |
1657 | "%u-%u from %u:%u\n", | |
1658 | from, to, le32_to_cpu(ex->ee_block), ee_len); | |
a86c6181 AT |
1659 | } |
1660 | return 0; | |
1661 | } | |
1662 | ||
1663 | static int | |
1664 | ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, | |
725d26d3 | 1665 | struct ext4_ext_path *path, ext4_lblk_t start) |
a86c6181 AT |
1666 | { |
1667 | int err = 0, correct_index = 0; | |
1668 | int depth = ext_depth(inode), credits; | |
1669 | struct ext4_extent_header *eh; | |
725d26d3 AK |
1670 | ext4_lblk_t a, b, block; |
1671 | unsigned num; | |
1672 | ext4_lblk_t ex_ee_block; | |
a86c6181 | 1673 | unsigned short ex_ee_len; |
a2df2a63 | 1674 | unsigned uninitialized = 0; |
a86c6181 AT |
1675 | struct ext4_extent *ex; |
1676 | ||
c29c0ae7 | 1677 | /* the header must be checked already in ext4_ext_remove_space() */ |
725d26d3 | 1678 | ext_debug("truncate since %u in leaf\n", start); |
a86c6181 AT |
1679 | if (!path[depth].p_hdr) |
1680 | path[depth].p_hdr = ext_block_hdr(path[depth].p_bh); | |
1681 | eh = path[depth].p_hdr; | |
1682 | BUG_ON(eh == NULL); | |
a86c6181 AT |
1683 | |
1684 | /* find where to start removing */ | |
1685 | ex = EXT_LAST_EXTENT(eh); | |
1686 | ||
1687 | ex_ee_block = le32_to_cpu(ex->ee_block); | |
a2df2a63 AA |
1688 | if (ext4_ext_is_uninitialized(ex)) |
1689 | uninitialized = 1; | |
1690 | ex_ee_len = ext4_ext_get_actual_len(ex); | |
a86c6181 AT |
1691 | |
1692 | while (ex >= EXT_FIRST_EXTENT(eh) && | |
1693 | ex_ee_block + ex_ee_len > start) { | |
1694 | ext_debug("remove ext %lu:%u\n", ex_ee_block, ex_ee_len); | |
1695 | path[depth].p_ext = ex; | |
1696 | ||
1697 | a = ex_ee_block > start ? ex_ee_block : start; | |
1698 | b = ex_ee_block + ex_ee_len - 1 < EXT_MAX_BLOCK ? | |
1699 | ex_ee_block + ex_ee_len - 1 : EXT_MAX_BLOCK; | |
1700 | ||
1701 | ext_debug(" border %u:%u\n", a, b); | |
1702 | ||
1703 | if (a != ex_ee_block && b != ex_ee_block + ex_ee_len - 1) { | |
1704 | block = 0; | |
1705 | num = 0; | |
1706 | BUG(); | |
1707 | } else if (a != ex_ee_block) { | |
1708 | /* remove tail of the extent */ | |
1709 | block = ex_ee_block; | |
1710 | num = a - block; | |
1711 | } else if (b != ex_ee_block + ex_ee_len - 1) { | |
1712 | /* remove head of the extent */ | |
1713 | block = a; | |
1714 | num = b - a; | |
1715 | /* there is no "make a hole" API yet */ | |
1716 | BUG(); | |
1717 | } else { | |
1718 | /* remove whole extent: excellent! */ | |
1719 | block = ex_ee_block; | |
1720 | num = 0; | |
1721 | BUG_ON(a != ex_ee_block); | |
1722 | BUG_ON(b != ex_ee_block + ex_ee_len - 1); | |
1723 | } | |
1724 | ||
d0d856e8 | 1725 | /* at present, extent can't cross block group: */ |
a86c6181 AT |
1726 | /* leaf + bitmap + group desc + sb + inode */ |
1727 | credits = 5; | |
1728 | if (ex == EXT_FIRST_EXTENT(eh)) { | |
1729 | correct_index = 1; | |
1730 | credits += (ext_depth(inode)) + 1; | |
1731 | } | |
1732 | #ifdef CONFIG_QUOTA | |
1733 | credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb); | |
1734 | #endif | |
1735 | ||
1736 | handle = ext4_ext_journal_restart(handle, credits); | |
1737 | if (IS_ERR(handle)) { | |
1738 | err = PTR_ERR(handle); | |
1739 | goto out; | |
1740 | } | |
1741 | ||
1742 | err = ext4_ext_get_access(handle, inode, path + depth); | |
1743 | if (err) | |
1744 | goto out; | |
1745 | ||
1746 | err = ext4_remove_blocks(handle, inode, ex, a, b); | |
1747 | if (err) | |
1748 | goto out; | |
1749 | ||
1750 | if (num == 0) { | |
d0d856e8 | 1751 | /* this extent is removed; mark slot entirely unused */ |
f65e6fba | 1752 | ext4_ext_store_pblock(ex, 0); |
a86c6181 AT |
1753 | eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1); |
1754 | } | |
1755 | ||
1756 | ex->ee_block = cpu_to_le32(block); | |
1757 | ex->ee_len = cpu_to_le16(num); | |
749269fa AA |
1758 | /* |
1759 | * Do not mark uninitialized if all the blocks in the | |
1760 | * extent have been removed. | |
1761 | */ | |
1762 | if (uninitialized && num) | |
a2df2a63 | 1763 | ext4_ext_mark_uninitialized(ex); |
a86c6181 AT |
1764 | |
1765 | err = ext4_ext_dirty(handle, inode, path + depth); | |
1766 | if (err) | |
1767 | goto out; | |
1768 | ||
2ae02107 | 1769 | ext_debug("new extent: %u:%u:%llu\n", block, num, |
f65e6fba | 1770 | ext_pblock(ex)); |
a86c6181 AT |
1771 | ex--; |
1772 | ex_ee_block = le32_to_cpu(ex->ee_block); | |
a2df2a63 | 1773 | ex_ee_len = ext4_ext_get_actual_len(ex); |
a86c6181 AT |
1774 | } |
1775 | ||
1776 | if (correct_index && eh->eh_entries) | |
1777 | err = ext4_ext_correct_indexes(handle, inode, path); | |
1778 | ||
1779 | /* if this leaf is free, then we should | |
1780 | * remove it from index block above */ | |
1781 | if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL) | |
1782 | err = ext4_ext_rm_idx(handle, inode, path + depth); | |
1783 | ||
1784 | out: | |
1785 | return err; | |
1786 | } | |
1787 | ||
1788 | /* | |
d0d856e8 RD |
1789 | * ext4_ext_more_to_rm: |
1790 | * returns 1 if current index has to be freed (even partial) | |
a86c6181 | 1791 | */ |
09b88252 | 1792 | static int |
a86c6181 AT |
1793 | ext4_ext_more_to_rm(struct ext4_ext_path *path) |
1794 | { | |
1795 | BUG_ON(path->p_idx == NULL); | |
1796 | ||
1797 | if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr)) | |
1798 | return 0; | |
1799 | ||
1800 | /* | |
d0d856e8 | 1801 | * if truncate on deeper level happened, it wasn't partial, |
a86c6181 AT |
1802 | * so we have to consider current index for truncation |
1803 | */ | |
1804 | if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block) | |
1805 | return 0; | |
1806 | return 1; | |
1807 | } | |
1808 | ||
725d26d3 | 1809 | int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start) |
a86c6181 AT |
1810 | { |
1811 | struct super_block *sb = inode->i_sb; | |
1812 | int depth = ext_depth(inode); | |
1813 | struct ext4_ext_path *path; | |
1814 | handle_t *handle; | |
1815 | int i = 0, err = 0; | |
1816 | ||
725d26d3 | 1817 | ext_debug("truncate since %u\n", start); |
a86c6181 AT |
1818 | |
1819 | /* probably first extent we're gonna free will be last in block */ | |
1820 | handle = ext4_journal_start(inode, depth + 1); | |
1821 | if (IS_ERR(handle)) | |
1822 | return PTR_ERR(handle); | |
1823 | ||
1824 | ext4_ext_invalidate_cache(inode); | |
1825 | ||
1826 | /* | |
d0d856e8 RD |
1827 | * We start scanning from right side, freeing all the blocks |
1828 | * after i_size and walking into the tree depth-wise. | |
a86c6181 | 1829 | */ |
5d4958f9 | 1830 | path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_KERNEL); |
a86c6181 AT |
1831 | if (path == NULL) { |
1832 | ext4_journal_stop(handle); | |
1833 | return -ENOMEM; | |
1834 | } | |
a86c6181 | 1835 | path[0].p_hdr = ext_inode_hdr(inode); |
c29c0ae7 | 1836 | if (ext4_ext_check_header(inode, path[0].p_hdr, depth)) { |
a86c6181 AT |
1837 | err = -EIO; |
1838 | goto out; | |
1839 | } | |
1840 | path[0].p_depth = depth; | |
1841 | ||
1842 | while (i >= 0 && err == 0) { | |
1843 | if (i == depth) { | |
1844 | /* this is leaf block */ | |
1845 | err = ext4_ext_rm_leaf(handle, inode, path, start); | |
d0d856e8 | 1846 | /* root level has p_bh == NULL, brelse() eats this */ |
a86c6181 AT |
1847 | brelse(path[i].p_bh); |
1848 | path[i].p_bh = NULL; | |
1849 | i--; | |
1850 | continue; | |
1851 | } | |
1852 | ||
1853 | /* this is index block */ | |
1854 | if (!path[i].p_hdr) { | |
1855 | ext_debug("initialize header\n"); | |
1856 | path[i].p_hdr = ext_block_hdr(path[i].p_bh); | |
a86c6181 AT |
1857 | } |
1858 | ||
a86c6181 | 1859 | if (!path[i].p_idx) { |
d0d856e8 | 1860 | /* this level hasn't been touched yet */ |
a86c6181 AT |
1861 | path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr); |
1862 | path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1; | |
1863 | ext_debug("init index ptr: hdr 0x%p, num %d\n", | |
1864 | path[i].p_hdr, | |
1865 | le16_to_cpu(path[i].p_hdr->eh_entries)); | |
1866 | } else { | |
d0d856e8 | 1867 | /* we were already here, see at next index */ |
a86c6181 AT |
1868 | path[i].p_idx--; |
1869 | } | |
1870 | ||
1871 | ext_debug("level %d - index, first 0x%p, cur 0x%p\n", | |
1872 | i, EXT_FIRST_INDEX(path[i].p_hdr), | |
1873 | path[i].p_idx); | |
1874 | if (ext4_ext_more_to_rm(path + i)) { | |
c29c0ae7 | 1875 | struct buffer_head *bh; |
a86c6181 | 1876 | /* go to the next level */ |
2ae02107 | 1877 | ext_debug("move to level %d (block %llu)\n", |
f65e6fba | 1878 | i + 1, idx_pblock(path[i].p_idx)); |
a86c6181 | 1879 | memset(path + i + 1, 0, sizeof(*path)); |
c29c0ae7 AT |
1880 | bh = sb_bread(sb, idx_pblock(path[i].p_idx)); |
1881 | if (!bh) { | |
a86c6181 AT |
1882 | /* should we reset i_size? */ |
1883 | err = -EIO; | |
1884 | break; | |
1885 | } | |
c29c0ae7 AT |
1886 | if (WARN_ON(i + 1 > depth)) { |
1887 | err = -EIO; | |
1888 | break; | |
1889 | } | |
1890 | if (ext4_ext_check_header(inode, ext_block_hdr(bh), | |
1891 | depth - i - 1)) { | |
1892 | err = -EIO; | |
1893 | break; | |
1894 | } | |
1895 | path[i + 1].p_bh = bh; | |
a86c6181 | 1896 | |
d0d856e8 RD |
1897 | /* save actual number of indexes since this |
1898 | * number is changed at the next iteration */ | |
a86c6181 AT |
1899 | path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries); |
1900 | i++; | |
1901 | } else { | |
d0d856e8 | 1902 | /* we finished processing this index, go up */ |
a86c6181 | 1903 | if (path[i].p_hdr->eh_entries == 0 && i > 0) { |
d0d856e8 | 1904 | /* index is empty, remove it; |
a86c6181 AT |
1905 | * handle must be already prepared by the |
1906 | * truncatei_leaf() */ | |
1907 | err = ext4_ext_rm_idx(handle, inode, path + i); | |
1908 | } | |
d0d856e8 | 1909 | /* root level has p_bh == NULL, brelse() eats this */ |
a86c6181 AT |
1910 | brelse(path[i].p_bh); |
1911 | path[i].p_bh = NULL; | |
1912 | i--; | |
1913 | ext_debug("return to level %d\n", i); | |
1914 | } | |
1915 | } | |
1916 | ||
1917 | /* TODO: flexible tree reduction should be here */ | |
1918 | if (path->p_hdr->eh_entries == 0) { | |
1919 | /* | |
d0d856e8 RD |
1920 | * truncate to zero freed all the tree, |
1921 | * so we need to correct eh_depth | |
a86c6181 AT |
1922 | */ |
1923 | err = ext4_ext_get_access(handle, inode, path); | |
1924 | if (err == 0) { | |
1925 | ext_inode_hdr(inode)->eh_depth = 0; | |
1926 | ext_inode_hdr(inode)->eh_max = | |
1927 | cpu_to_le16(ext4_ext_space_root(inode)); | |
1928 | err = ext4_ext_dirty(handle, inode, path); | |
1929 | } | |
1930 | } | |
1931 | out: | |
1932 | ext4_ext_tree_changed(inode); | |
1933 | ext4_ext_drop_refs(path); | |
1934 | kfree(path); | |
1935 | ext4_journal_stop(handle); | |
1936 | ||
1937 | return err; | |
1938 | } | |
1939 | ||
1940 | /* | |
1941 | * called at mount time | |
1942 | */ | |
1943 | void ext4_ext_init(struct super_block *sb) | |
1944 | { | |
1945 | /* | |
1946 | * possible initialization would be here | |
1947 | */ | |
1948 | ||
1949 | if (test_opt(sb, EXTENTS)) { | |
1950 | printk("EXT4-fs: file extents enabled"); | |
bbf2f9fb RD |
1951 | #ifdef AGGRESSIVE_TEST |
1952 | printk(", aggressive tests"); | |
a86c6181 AT |
1953 | #endif |
1954 | #ifdef CHECK_BINSEARCH | |
1955 | printk(", check binsearch"); | |
1956 | #endif | |
1957 | #ifdef EXTENTS_STATS | |
1958 | printk(", stats"); | |
1959 | #endif | |
1960 | printk("\n"); | |
1961 | #ifdef EXTENTS_STATS | |
1962 | spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock); | |
1963 | EXT4_SB(sb)->s_ext_min = 1 << 30; | |
1964 | EXT4_SB(sb)->s_ext_max = 0; | |
1965 | #endif | |
1966 | } | |
1967 | } | |
1968 | ||
1969 | /* | |
1970 | * called at umount time | |
1971 | */ | |
1972 | void ext4_ext_release(struct super_block *sb) | |
1973 | { | |
1974 | if (!test_opt(sb, EXTENTS)) | |
1975 | return; | |
1976 | ||
1977 | #ifdef EXTENTS_STATS | |
1978 | if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) { | |
1979 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
1980 | printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n", | |
1981 | sbi->s_ext_blocks, sbi->s_ext_extents, | |
1982 | sbi->s_ext_blocks / sbi->s_ext_extents); | |
1983 | printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n", | |
1984 | sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max); | |
1985 | } | |
1986 | #endif | |
1987 | } | |
1988 | ||
56055d3a AA |
1989 | /* |
1990 | * This function is called by ext4_ext_get_blocks() if someone tries to write | |
1991 | * to an uninitialized extent. It may result in splitting the uninitialized | |
1992 | * extent into multiple extents (upto three - one initialized and two | |
1993 | * uninitialized). | |
1994 | * There are three possibilities: | |
1995 | * a> There is no split required: Entire extent should be initialized | |
1996 | * b> Splits in two extents: Write is happening at either end of the extent | |
1997 | * c> Splits in three extents: Somone is writing in middle of the extent | |
1998 | */ | |
725d26d3 AK |
1999 | static int ext4_ext_convert_to_initialized(handle_t *handle, |
2000 | struct inode *inode, | |
2001 | struct ext4_ext_path *path, | |
2002 | ext4_lblk_t iblock, | |
2003 | unsigned long max_blocks) | |
56055d3a AA |
2004 | { |
2005 | struct ext4_extent *ex, newex; | |
2006 | struct ext4_extent *ex1 = NULL; | |
2007 | struct ext4_extent *ex2 = NULL; | |
2008 | struct ext4_extent *ex3 = NULL; | |
2009 | struct ext4_extent_header *eh; | |
725d26d3 AK |
2010 | ext4_lblk_t ee_block; |
2011 | unsigned int allocated, ee_len, depth; | |
56055d3a AA |
2012 | ext4_fsblk_t newblock; |
2013 | int err = 0; | |
2014 | int ret = 0; | |
2015 | ||
2016 | depth = ext_depth(inode); | |
2017 | eh = path[depth].p_hdr; | |
2018 | ex = path[depth].p_ext; | |
2019 | ee_block = le32_to_cpu(ex->ee_block); | |
2020 | ee_len = ext4_ext_get_actual_len(ex); | |
2021 | allocated = ee_len - (iblock - ee_block); | |
2022 | newblock = iblock - ee_block + ext_pblock(ex); | |
2023 | ex2 = ex; | |
2024 | ||
2025 | /* ex1: ee_block to iblock - 1 : uninitialized */ | |
2026 | if (iblock > ee_block) { | |
2027 | ex1 = ex; | |
2028 | ex1->ee_len = cpu_to_le16(iblock - ee_block); | |
2029 | ext4_ext_mark_uninitialized(ex1); | |
2030 | ex2 = &newex; | |
2031 | } | |
2032 | /* | |
2033 | * for sanity, update the length of the ex2 extent before | |
2034 | * we insert ex3, if ex1 is NULL. This is to avoid temporary | |
2035 | * overlap of blocks. | |
2036 | */ | |
2037 | if (!ex1 && allocated > max_blocks) | |
2038 | ex2->ee_len = cpu_to_le16(max_blocks); | |
2039 | /* ex3: to ee_block + ee_len : uninitialised */ | |
2040 | if (allocated > max_blocks) { | |
2041 | unsigned int newdepth; | |
2042 | ex3 = &newex; | |
2043 | ex3->ee_block = cpu_to_le32(iblock + max_blocks); | |
2044 | ext4_ext_store_pblock(ex3, newblock + max_blocks); | |
2045 | ex3->ee_len = cpu_to_le16(allocated - max_blocks); | |
2046 | ext4_ext_mark_uninitialized(ex3); | |
2047 | err = ext4_ext_insert_extent(handle, inode, path, ex3); | |
2048 | if (err) | |
2049 | goto out; | |
2050 | /* | |
2051 | * The depth, and hence eh & ex might change | |
2052 | * as part of the insert above. | |
2053 | */ | |
2054 | newdepth = ext_depth(inode); | |
2055 | if (newdepth != depth) { | |
2056 | depth = newdepth; | |
2057 | path = ext4_ext_find_extent(inode, iblock, NULL); | |
2058 | if (IS_ERR(path)) { | |
2059 | err = PTR_ERR(path); | |
2060 | path = NULL; | |
2061 | goto out; | |
2062 | } | |
2063 | eh = path[depth].p_hdr; | |
2064 | ex = path[depth].p_ext; | |
2065 | if (ex2 != &newex) | |
2066 | ex2 = ex; | |
2067 | } | |
2068 | allocated = max_blocks; | |
2069 | } | |
2070 | /* | |
2071 | * If there was a change of depth as part of the | |
2072 | * insertion of ex3 above, we need to update the length | |
2073 | * of the ex1 extent again here | |
2074 | */ | |
2075 | if (ex1 && ex1 != ex) { | |
2076 | ex1 = ex; | |
2077 | ex1->ee_len = cpu_to_le16(iblock - ee_block); | |
2078 | ext4_ext_mark_uninitialized(ex1); | |
2079 | ex2 = &newex; | |
2080 | } | |
2081 | /* ex2: iblock to iblock + maxblocks-1 : initialised */ | |
2082 | ex2->ee_block = cpu_to_le32(iblock); | |
56055d3a AA |
2083 | ext4_ext_store_pblock(ex2, newblock); |
2084 | ex2->ee_len = cpu_to_le16(allocated); | |
2085 | if (ex2 != ex) | |
2086 | goto insert; | |
2087 | err = ext4_ext_get_access(handle, inode, path + depth); | |
2088 | if (err) | |
2089 | goto out; | |
2090 | /* | |
2091 | * New (initialized) extent starts from the first block | |
2092 | * in the current extent. i.e., ex2 == ex | |
2093 | * We have to see if it can be merged with the extent | |
2094 | * on the left. | |
2095 | */ | |
2096 | if (ex2 > EXT_FIRST_EXTENT(eh)) { | |
2097 | /* | |
2098 | * To merge left, pass "ex2 - 1" to try_to_merge(), | |
2099 | * since it merges towards right _only_. | |
2100 | */ | |
2101 | ret = ext4_ext_try_to_merge(inode, path, ex2 - 1); | |
2102 | if (ret) { | |
2103 | err = ext4_ext_correct_indexes(handle, inode, path); | |
2104 | if (err) | |
2105 | goto out; | |
2106 | depth = ext_depth(inode); | |
2107 | ex2--; | |
2108 | } | |
2109 | } | |
2110 | /* | |
2111 | * Try to Merge towards right. This might be required | |
2112 | * only when the whole extent is being written to. | |
2113 | * i.e. ex2 == ex and ex3 == NULL. | |
2114 | */ | |
2115 | if (!ex3) { | |
2116 | ret = ext4_ext_try_to_merge(inode, path, ex2); | |
2117 | if (ret) { | |
2118 | err = ext4_ext_correct_indexes(handle, inode, path); | |
2119 | if (err) | |
2120 | goto out; | |
2121 | } | |
2122 | } | |
2123 | /* Mark modified extent as dirty */ | |
2124 | err = ext4_ext_dirty(handle, inode, path + depth); | |
2125 | goto out; | |
2126 | insert: | |
2127 | err = ext4_ext_insert_extent(handle, inode, path, &newex); | |
2128 | out: | |
2129 | return err ? err : allocated; | |
2130 | } | |
2131 | ||
f65e6fba | 2132 | int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, |
725d26d3 | 2133 | ext4_lblk_t iblock, |
a86c6181 AT |
2134 | unsigned long max_blocks, struct buffer_head *bh_result, |
2135 | int create, int extend_disksize) | |
2136 | { | |
2137 | struct ext4_ext_path *path = NULL; | |
56055d3a | 2138 | struct ext4_extent_header *eh; |
a86c6181 | 2139 | struct ext4_extent newex, *ex; |
f65e6fba | 2140 | ext4_fsblk_t goal, newblock; |
56055d3a | 2141 | int err = 0, depth, ret; |
a86c6181 AT |
2142 | unsigned long allocated = 0; |
2143 | ||
2144 | __clear_bit(BH_New, &bh_result->b_state); | |
bba90743 ES |
2145 | ext_debug("blocks %u/%lu requested for inode %u\n", |
2146 | iblock, max_blocks, inode->i_ino); | |
a86c6181 AT |
2147 | mutex_lock(&EXT4_I(inode)->truncate_mutex); |
2148 | ||
2149 | /* check in cache */ | |
7e028976 AM |
2150 | goal = ext4_ext_in_cache(inode, iblock, &newex); |
2151 | if (goal) { | |
a86c6181 AT |
2152 | if (goal == EXT4_EXT_CACHE_GAP) { |
2153 | if (!create) { | |
56055d3a AA |
2154 | /* |
2155 | * block isn't allocated yet and | |
2156 | * user doesn't want to allocate it | |
2157 | */ | |
a86c6181 AT |
2158 | goto out2; |
2159 | } | |
2160 | /* we should allocate requested block */ | |
2161 | } else if (goal == EXT4_EXT_CACHE_EXTENT) { | |
2162 | /* block is already allocated */ | |
8c55e204 DK |
2163 | newblock = iblock |
2164 | - le32_to_cpu(newex.ee_block) | |
2165 | + ext_pblock(&newex); | |
d0d856e8 | 2166 | /* number of remaining blocks in the extent */ |
a86c6181 AT |
2167 | allocated = le16_to_cpu(newex.ee_len) - |
2168 | (iblock - le32_to_cpu(newex.ee_block)); | |
2169 | goto out; | |
2170 | } else { | |
2171 | BUG(); | |
2172 | } | |
2173 | } | |
2174 | ||
2175 | /* find extent for this block */ | |
2176 | path = ext4_ext_find_extent(inode, iblock, NULL); | |
2177 | if (IS_ERR(path)) { | |
2178 | err = PTR_ERR(path); | |
2179 | path = NULL; | |
2180 | goto out2; | |
2181 | } | |
2182 | ||
2183 | depth = ext_depth(inode); | |
2184 | ||
2185 | /* | |
d0d856e8 RD |
2186 | * consistent leaf must not be empty; |
2187 | * this situation is possible, though, _during_ tree modification; | |
a86c6181 AT |
2188 | * this is why assert can't be put in ext4_ext_find_extent() |
2189 | */ | |
2190 | BUG_ON(path[depth].p_ext == NULL && depth != 0); | |
56055d3a | 2191 | eh = path[depth].p_hdr; |
a86c6181 | 2192 | |
7e028976 AM |
2193 | ex = path[depth].p_ext; |
2194 | if (ex) { | |
725d26d3 | 2195 | ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block); |
f65e6fba | 2196 | ext4_fsblk_t ee_start = ext_pblock(ex); |
a2df2a63 | 2197 | unsigned short ee_len; |
471d4011 SB |
2198 | |
2199 | /* | |
471d4011 | 2200 | * Uninitialized extents are treated as holes, except that |
56055d3a | 2201 | * we split out initialized portions during a write. |
471d4011 | 2202 | */ |
a2df2a63 | 2203 | ee_len = ext4_ext_get_actual_len(ex); |
d0d856e8 | 2204 | /* if found extent covers block, simply return it */ |
8c55e204 | 2205 | if (iblock >= ee_block && iblock < ee_block + ee_len) { |
a86c6181 | 2206 | newblock = iblock - ee_block + ee_start; |
d0d856e8 | 2207 | /* number of remaining blocks in the extent */ |
a86c6181 | 2208 | allocated = ee_len - (iblock - ee_block); |
bba90743 | 2209 | ext_debug("%u fit into %lu:%d -> %llu\n", iblock, |
a86c6181 | 2210 | ee_block, ee_len, newblock); |
56055d3a | 2211 | |
a2df2a63 | 2212 | /* Do not put uninitialized extent in the cache */ |
56055d3a | 2213 | if (!ext4_ext_is_uninitialized(ex)) { |
a2df2a63 AA |
2214 | ext4_ext_put_in_cache(inode, ee_block, |
2215 | ee_len, ee_start, | |
2216 | EXT4_EXT_CACHE_EXTENT); | |
56055d3a AA |
2217 | goto out; |
2218 | } | |
2219 | if (create == EXT4_CREATE_UNINITIALIZED_EXT) | |
2220 | goto out; | |
2221 | if (!create) | |
2222 | goto out2; | |
2223 | ||
2224 | ret = ext4_ext_convert_to_initialized(handle, inode, | |
2225 | path, iblock, | |
2226 | max_blocks); | |
2227 | if (ret <= 0) | |
2228 | goto out2; | |
2229 | else | |
2230 | allocated = ret; | |
2231 | goto outnew; | |
a86c6181 AT |
2232 | } |
2233 | } | |
2234 | ||
2235 | /* | |
d0d856e8 | 2236 | * requested block isn't allocated yet; |
a86c6181 AT |
2237 | * we couldn't try to create block if create flag is zero |
2238 | */ | |
2239 | if (!create) { | |
56055d3a AA |
2240 | /* |
2241 | * put just found gap into cache to speed up | |
2242 | * subsequent requests | |
2243 | */ | |
a86c6181 AT |
2244 | ext4_ext_put_gap_in_cache(inode, path, iblock); |
2245 | goto out2; | |
2246 | } | |
2247 | /* | |
63f57933 AM |
2248 | * Okay, we need to do block allocation. Lazily initialize the block |
2249 | * allocation info here if necessary. | |
2250 | */ | |
a86c6181 AT |
2251 | if (S_ISREG(inode->i_mode) && (!EXT4_I(inode)->i_block_alloc_info)) |
2252 | ext4_init_block_alloc_info(inode); | |
2253 | ||
2254 | /* allocate new block */ | |
2255 | goal = ext4_ext_find_goal(inode, path, iblock); | |
25d14f98 | 2256 | |
749269fa AA |
2257 | /* |
2258 | * See if request is beyond maximum number of blocks we can have in | |
2259 | * a single extent. For an initialized extent this limit is | |
2260 | * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is | |
2261 | * EXT_UNINIT_MAX_LEN. | |
2262 | */ | |
2263 | if (max_blocks > EXT_INIT_MAX_LEN && | |
2264 | create != EXT4_CREATE_UNINITIALIZED_EXT) | |
2265 | max_blocks = EXT_INIT_MAX_LEN; | |
2266 | else if (max_blocks > EXT_UNINIT_MAX_LEN && | |
2267 | create == EXT4_CREATE_UNINITIALIZED_EXT) | |
2268 | max_blocks = EXT_UNINIT_MAX_LEN; | |
2269 | ||
25d14f98 AA |
2270 | /* Check if we can really insert (iblock)::(iblock+max_blocks) extent */ |
2271 | newex.ee_block = cpu_to_le32(iblock); | |
2272 | newex.ee_len = cpu_to_le16(max_blocks); | |
2273 | err = ext4_ext_check_overlap(inode, &newex, path); | |
2274 | if (err) | |
2275 | allocated = le16_to_cpu(newex.ee_len); | |
2276 | else | |
2277 | allocated = max_blocks; | |
a86c6181 AT |
2278 | newblock = ext4_new_blocks(handle, inode, goal, &allocated, &err); |
2279 | if (!newblock) | |
2280 | goto out2; | |
2ae02107 | 2281 | ext_debug("allocate new block: goal %llu, found %llu/%lu\n", |
a86c6181 AT |
2282 | goal, newblock, allocated); |
2283 | ||
2284 | /* try to insert new extent into found leaf and return */ | |
f65e6fba | 2285 | ext4_ext_store_pblock(&newex, newblock); |
a86c6181 | 2286 | newex.ee_len = cpu_to_le16(allocated); |
a2df2a63 AA |
2287 | if (create == EXT4_CREATE_UNINITIALIZED_EXT) /* Mark uninitialized */ |
2288 | ext4_ext_mark_uninitialized(&newex); | |
a86c6181 | 2289 | err = ext4_ext_insert_extent(handle, inode, path, &newex); |
315054f0 AT |
2290 | if (err) { |
2291 | /* free data blocks we just allocated */ | |
2292 | ext4_free_blocks(handle, inode, ext_pblock(&newex), | |
2293 | le16_to_cpu(newex.ee_len)); | |
a86c6181 | 2294 | goto out2; |
315054f0 | 2295 | } |
a86c6181 AT |
2296 | |
2297 | if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize) | |
2298 | EXT4_I(inode)->i_disksize = inode->i_size; | |
2299 | ||
2300 | /* previous routine could use block we allocated */ | |
f65e6fba | 2301 | newblock = ext_pblock(&newex); |
56055d3a | 2302 | outnew: |
a86c6181 AT |
2303 | __set_bit(BH_New, &bh_result->b_state); |
2304 | ||
a2df2a63 AA |
2305 | /* Cache only when it is _not_ an uninitialized extent */ |
2306 | if (create != EXT4_CREATE_UNINITIALIZED_EXT) | |
2307 | ext4_ext_put_in_cache(inode, iblock, allocated, newblock, | |
2308 | EXT4_EXT_CACHE_EXTENT); | |
a86c6181 AT |
2309 | out: |
2310 | if (allocated > max_blocks) | |
2311 | allocated = max_blocks; | |
2312 | ext4_ext_show_leaf(inode, path); | |
2313 | __set_bit(BH_Mapped, &bh_result->b_state); | |
2314 | bh_result->b_bdev = inode->i_sb->s_bdev; | |
2315 | bh_result->b_blocknr = newblock; | |
2316 | out2: | |
2317 | if (path) { | |
2318 | ext4_ext_drop_refs(path); | |
2319 | kfree(path); | |
2320 | } | |
2321 | mutex_unlock(&EXT4_I(inode)->truncate_mutex); | |
2322 | ||
2323 | return err ? err : allocated; | |
2324 | } | |
2325 | ||
2326 | void ext4_ext_truncate(struct inode * inode, struct page *page) | |
2327 | { | |
2328 | struct address_space *mapping = inode->i_mapping; | |
2329 | struct super_block *sb = inode->i_sb; | |
725d26d3 | 2330 | ext4_lblk_t last_block; |
a86c6181 AT |
2331 | handle_t *handle; |
2332 | int err = 0; | |
2333 | ||
2334 | /* | |
2335 | * probably first extent we're gonna free will be last in block | |
2336 | */ | |
2337 | err = ext4_writepage_trans_blocks(inode) + 3; | |
2338 | handle = ext4_journal_start(inode, err); | |
2339 | if (IS_ERR(handle)) { | |
2340 | if (page) { | |
2341 | clear_highpage(page); | |
2342 | flush_dcache_page(page); | |
2343 | unlock_page(page); | |
2344 | page_cache_release(page); | |
2345 | } | |
2346 | return; | |
2347 | } | |
2348 | ||
2349 | if (page) | |
2350 | ext4_block_truncate_page(handle, page, mapping, inode->i_size); | |
2351 | ||
2352 | mutex_lock(&EXT4_I(inode)->truncate_mutex); | |
2353 | ext4_ext_invalidate_cache(inode); | |
2354 | ||
2355 | /* | |
d0d856e8 RD |
2356 | * TODO: optimization is possible here. |
2357 | * Probably we need not scan at all, | |
2358 | * because page truncation is enough. | |
a86c6181 AT |
2359 | */ |
2360 | if (ext4_orphan_add(handle, inode)) | |
2361 | goto out_stop; | |
2362 | ||
2363 | /* we have to know where to truncate from in crash case */ | |
2364 | EXT4_I(inode)->i_disksize = inode->i_size; | |
2365 | ext4_mark_inode_dirty(handle, inode); | |
2366 | ||
2367 | last_block = (inode->i_size + sb->s_blocksize - 1) | |
2368 | >> EXT4_BLOCK_SIZE_BITS(sb); | |
2369 | err = ext4_ext_remove_space(inode, last_block); | |
2370 | ||
2371 | /* In a multi-transaction truncate, we only make the final | |
56055d3a AA |
2372 | * transaction synchronous. |
2373 | */ | |
a86c6181 AT |
2374 | if (IS_SYNC(inode)) |
2375 | handle->h_sync = 1; | |
2376 | ||
2377 | out_stop: | |
2378 | /* | |
d0d856e8 | 2379 | * If this was a simple ftruncate() and the file will remain alive, |
a86c6181 AT |
2380 | * then we need to clear up the orphan record which we created above. |
2381 | * However, if this was a real unlink then we were called by | |
2382 | * ext4_delete_inode(), and we allow that function to clean up the | |
2383 | * orphan info for us. | |
2384 | */ | |
2385 | if (inode->i_nlink) | |
2386 | ext4_orphan_del(handle, inode); | |
2387 | ||
2388 | mutex_unlock(&EXT4_I(inode)->truncate_mutex); | |
2389 | ext4_journal_stop(handle); | |
2390 | } | |
2391 | ||
2392 | /* | |
d0d856e8 RD |
2393 | * ext4_ext_writepage_trans_blocks: |
2394 | * calculate max number of blocks we could modify | |
a86c6181 AT |
2395 | * in order to allocate new block for an inode |
2396 | */ | |
2397 | int ext4_ext_writepage_trans_blocks(struct inode *inode, int num) | |
2398 | { | |
2399 | int needed; | |
2400 | ||
2401 | needed = ext4_ext_calc_credits_for_insert(inode, NULL); | |
2402 | ||
d0d856e8 | 2403 | /* caller wants to allocate num blocks, but note it includes sb */ |
a86c6181 AT |
2404 | needed = needed * num - (num - 1); |
2405 | ||
2406 | #ifdef CONFIG_QUOTA | |
2407 | needed += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb); | |
2408 | #endif | |
2409 | ||
2410 | return needed; | |
2411 | } | |
a2df2a63 AA |
2412 | |
2413 | /* | |
2414 | * preallocate space for a file. This implements ext4's fallocate inode | |
2415 | * operation, which gets called from sys_fallocate system call. | |
2416 | * For block-mapped files, posix_fallocate should fall back to the method | |
2417 | * of writing zeroes to the required new blocks (the same behavior which is | |
2418 | * expected for file systems which do not support fallocate() system call). | |
2419 | */ | |
2420 | long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len) | |
2421 | { | |
2422 | handle_t *handle; | |
725d26d3 AK |
2423 | ext4_lblk_t block; |
2424 | unsigned long max_blocks; | |
a2df2a63 AA |
2425 | ext4_fsblk_t nblocks = 0; |
2426 | int ret = 0; | |
2427 | int ret2 = 0; | |
2428 | int retries = 0; | |
2429 | struct buffer_head map_bh; | |
2430 | unsigned int credits, blkbits = inode->i_blkbits; | |
2431 | ||
2432 | /* | |
2433 | * currently supporting (pre)allocate mode for extent-based | |
2434 | * files _only_ | |
2435 | */ | |
2436 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) | |
2437 | return -EOPNOTSUPP; | |
2438 | ||
2439 | /* preallocation to directories is currently not supported */ | |
2440 | if (S_ISDIR(inode->i_mode)) | |
2441 | return -ENODEV; | |
2442 | ||
2443 | block = offset >> blkbits; | |
2444 | max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) | |
2445 | - block; | |
2446 | ||
2447 | /* | |
2448 | * credits to insert 1 extent into extent tree + buffers to be able to | |
2449 | * modify 1 super block, 1 block bitmap and 1 group descriptor. | |
2450 | */ | |
2451 | credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + 3; | |
2452 | retry: | |
2453 | while (ret >= 0 && ret < max_blocks) { | |
2454 | block = block + ret; | |
2455 | max_blocks = max_blocks - ret; | |
2456 | handle = ext4_journal_start(inode, credits); | |
2457 | if (IS_ERR(handle)) { | |
2458 | ret = PTR_ERR(handle); | |
2459 | break; | |
2460 | } | |
2461 | ||
2462 | ret = ext4_ext_get_blocks(handle, inode, block, | |
2463 | max_blocks, &map_bh, | |
2464 | EXT4_CREATE_UNINITIALIZED_EXT, 0); | |
2465 | WARN_ON(!ret); | |
2466 | if (!ret) { | |
2467 | ext4_error(inode->i_sb, "ext4_fallocate", | |
2468 | "ext4_ext_get_blocks returned 0! inode#%lu" | |
bba90743 ES |
2469 | ", block=%u, max_blocks=%lu", |
2470 | inode->i_ino, block, max_blocks); | |
a2df2a63 AA |
2471 | ret = -EIO; |
2472 | ext4_mark_inode_dirty(handle, inode); | |
2473 | ret2 = ext4_journal_stop(handle); | |
2474 | break; | |
2475 | } | |
2476 | if (ret > 0) { | |
2477 | /* check wrap through sign-bit/zero here */ | |
2478 | if ((block + ret) < 0 || (block + ret) < block) { | |
2479 | ret = -EIO; | |
2480 | ext4_mark_inode_dirty(handle, inode); | |
2481 | ret2 = ext4_journal_stop(handle); | |
2482 | break; | |
2483 | } | |
2484 | if (buffer_new(&map_bh) && ((block + ret) > | |
2485 | (EXT4_BLOCK_ALIGN(i_size_read(inode), blkbits) | |
2486 | >> blkbits))) | |
2487 | nblocks = nblocks + ret; | |
2488 | } | |
2489 | ||
2490 | /* Update ctime if new blocks get allocated */ | |
2491 | if (nblocks) { | |
2492 | struct timespec now; | |
2493 | ||
2494 | now = current_fs_time(inode->i_sb); | |
2495 | if (!timespec_equal(&inode->i_ctime, &now)) | |
2496 | inode->i_ctime = now; | |
2497 | } | |
2498 | ||
2499 | ext4_mark_inode_dirty(handle, inode); | |
2500 | ret2 = ext4_journal_stop(handle); | |
2501 | if (ret2) | |
2502 | break; | |
2503 | } | |
2504 | ||
2505 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) | |
2506 | goto retry; | |
2507 | ||
2508 | /* | |
2509 | * Time to update the file size. | |
2510 | * Update only when preallocation was requested beyond the file size. | |
2511 | */ | |
2512 | if (!(mode & FALLOC_FL_KEEP_SIZE) && | |
2513 | (offset + len) > i_size_read(inode)) { | |
2514 | if (ret > 0) { | |
2515 | /* | |
2516 | * if no error, we assume preallocation succeeded | |
2517 | * completely | |
2518 | */ | |
2519 | mutex_lock(&inode->i_mutex); | |
2520 | i_size_write(inode, offset + len); | |
2521 | EXT4_I(inode)->i_disksize = i_size_read(inode); | |
2522 | mutex_unlock(&inode->i_mutex); | |
2523 | } else if (ret < 0 && nblocks) { | |
2524 | /* Handle partial allocation scenario */ | |
2525 | loff_t newsize; | |
2526 | ||
2527 | mutex_lock(&inode->i_mutex); | |
2528 | newsize = (nblocks << blkbits) + i_size_read(inode); | |
2529 | i_size_write(inode, EXT4_BLOCK_ALIGN(newsize, blkbits)); | |
2530 | EXT4_I(inode)->i_disksize = i_size_read(inode); | |
2531 | mutex_unlock(&inode->i_mutex); | |
2532 | } | |
2533 | } | |
2534 | ||
2535 | return ret > 0 ? ret2 : ret; | |
2536 | } |