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-rw-r--r--fs/ext4/extents.c682
1 files changed, 548 insertions, 134 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index b9ce24129070..750c46f7d893 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -39,6 +39,7 @@
39#include <linux/quotaops.h> 39#include <linux/quotaops.h>
40#include <linux/string.h> 40#include <linux/string.h>
41#include <linux/slab.h> 41#include <linux/slab.h>
42#include <linux/falloc.h>
42#include <linux/ext4_fs_extents.h> 43#include <linux/ext4_fs_extents.h>
43#include <asm/uaccess.h> 44#include <asm/uaccess.h>
44 45
@@ -91,36 +92,6 @@ static void ext4_idx_store_pblock(struct ext4_extent_idx *ix, ext4_fsblk_t pb)
91 ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff); 92 ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
92} 93}
93 94
94static int ext4_ext_check_header(const char *function, struct inode *inode,
95 struct ext4_extent_header *eh)
96{
97 const char *error_msg = NULL;
98
99 if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
100 error_msg = "invalid magic";
101 goto corrupted;
102 }
103 if (unlikely(eh->eh_max == 0)) {
104 error_msg = "invalid eh_max";
105 goto corrupted;
106 }
107 if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
108 error_msg = "invalid eh_entries";
109 goto corrupted;
110 }
111 return 0;
112
113corrupted:
114 ext4_error(inode->i_sb, function,
115 "bad header in inode #%lu: %s - magic %x, "
116 "entries %u, max %u, depth %u",
117 inode->i_ino, error_msg, le16_to_cpu(eh->eh_magic),
118 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
119 le16_to_cpu(eh->eh_depth));
120
121 return -EIO;
122}
123
124static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed) 95static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed)
125{ 96{
126 int err; 97 int err;
@@ -269,6 +240,70 @@ static int ext4_ext_space_root_idx(struct inode *inode)
269 return size; 240 return size;
270} 241}
271 242
243static int
244ext4_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
263static 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
293corrupted:
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
272#ifdef EXT_DEBUG 307#ifdef EXT_DEBUG
273static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path) 308static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
274{ 309{
@@ -282,7 +317,7 @@ static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
282 } else if (path->p_ext) { 317 } else if (path->p_ext) {
283 ext_debug(" %d:%d:%llu ", 318 ext_debug(" %d:%d:%llu ",
284 le32_to_cpu(path->p_ext->ee_block), 319 le32_to_cpu(path->p_ext->ee_block),
285 le16_to_cpu(path->p_ext->ee_len), 320 ext4_ext_get_actual_len(path->p_ext),
286 ext_pblock(path->p_ext)); 321 ext_pblock(path->p_ext));
287 } else 322 } else
288 ext_debug(" []"); 323 ext_debug(" []");
@@ -305,7 +340,7 @@ static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
305 340
306 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) { 341 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
307 ext_debug("%d:%d:%llu ", le32_to_cpu(ex->ee_block), 342 ext_debug("%d:%d:%llu ", le32_to_cpu(ex->ee_block),
308 le16_to_cpu(ex->ee_len), ext_pblock(ex)); 343 ext4_ext_get_actual_len(ex), ext_pblock(ex));
309 } 344 }
310 ext_debug("\n"); 345 ext_debug("\n");
311} 346}
@@ -329,6 +364,7 @@ static void ext4_ext_drop_refs(struct ext4_ext_path *path)
329/* 364/*
330 * ext4_ext_binsearch_idx: 365 * ext4_ext_binsearch_idx:
331 * binary search for the closest index of the given block 366 * binary search for the closest index of the given block
367 * the header must be checked before calling this
332 */ 368 */
333static void 369static void
334ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int block) 370ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int block)
@@ -336,27 +372,25 @@ ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int bloc
336 struct ext4_extent_header *eh = path->p_hdr; 372 struct ext4_extent_header *eh = path->p_hdr;
337 struct ext4_extent_idx *r, *l, *m; 373 struct ext4_extent_idx *r, *l, *m;
338 374
339 BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
340 BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
341 BUG_ON(le16_to_cpu(eh->eh_entries) <= 0);
342 375
343 ext_debug("binsearch for %d(idx): ", block); 376 ext_debug("binsearch for %d(idx): ", block);
344 377
345 l = EXT_FIRST_INDEX(eh) + 1; 378 l = EXT_FIRST_INDEX(eh) + 1;
346 r = EXT_FIRST_INDEX(eh) + le16_to_cpu(eh->eh_entries) - 1; 379 r = EXT_LAST_INDEX(eh);
347 while (l <= r) { 380 while (l <= r) {
348 m = l + (r - l) / 2; 381 m = l + (r - l) / 2;
349 if (block < le32_to_cpu(m->ei_block)) 382 if (block < le32_to_cpu(m->ei_block))
350 r = m - 1; 383 r = m - 1;
351 else 384 else
352 l = m + 1; 385 l = m + 1;
353 ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ei_block, 386 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block),
354 m, m->ei_block, r, r->ei_block); 387 m, le32_to_cpu(m->ei_block),
388 r, le32_to_cpu(r->ei_block));
355 } 389 }
356 390
357 path->p_idx = l - 1; 391 path->p_idx = l - 1;
358 ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block), 392 ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block),
359 idx_block(path->p_idx)); 393 idx_pblock(path->p_idx));
360 394
361#ifdef CHECK_BINSEARCH 395#ifdef CHECK_BINSEARCH
362 { 396 {
@@ -388,6 +422,7 @@ ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int bloc
388/* 422/*
389 * ext4_ext_binsearch: 423 * ext4_ext_binsearch:
390 * binary search for closest extent of the given block 424 * binary search for closest extent of the given block
425 * the header must be checked before calling this
391 */ 426 */
392static void 427static void
393ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block) 428ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
@@ -395,9 +430,6 @@ ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
395 struct ext4_extent_header *eh = path->p_hdr; 430 struct ext4_extent_header *eh = path->p_hdr;
396 struct ext4_extent *r, *l, *m; 431 struct ext4_extent *r, *l, *m;
397 432
398 BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
399 BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
400
401 if (eh->eh_entries == 0) { 433 if (eh->eh_entries == 0) {
402 /* 434 /*
403 * this leaf is empty: 435 * this leaf is empty:
@@ -409,7 +441,7 @@ ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
409 ext_debug("binsearch for %d: ", block); 441 ext_debug("binsearch for %d: ", block);
410 442
411 l = EXT_FIRST_EXTENT(eh) + 1; 443 l = EXT_FIRST_EXTENT(eh) + 1;
412 r = EXT_FIRST_EXTENT(eh) + le16_to_cpu(eh->eh_entries) - 1; 444 r = EXT_LAST_EXTENT(eh);
413 445
414 while (l <= r) { 446 while (l <= r) {
415 m = l + (r - l) / 2; 447 m = l + (r - l) / 2;
@@ -417,15 +449,16 @@ ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
417 r = m - 1; 449 r = m - 1;
418 else 450 else
419 l = m + 1; 451 l = m + 1;
420 ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ee_block, 452 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block),
421 m, m->ee_block, r, r->ee_block); 453 m, le32_to_cpu(m->ee_block),
454 r, le32_to_cpu(r->ee_block));
422 } 455 }
423 456
424 path->p_ext = l - 1; 457 path->p_ext = l - 1;
425 ext_debug(" -> %d:%llu:%d ", 458 ext_debug(" -> %d:%llu:%d ",
426 le32_to_cpu(path->p_ext->ee_block), 459 le32_to_cpu(path->p_ext->ee_block),
427 ext_pblock(path->p_ext), 460 ext_pblock(path->p_ext),
428 le16_to_cpu(path->p_ext->ee_len)); 461 ext4_ext_get_actual_len(path->p_ext));
429 462
430#ifdef CHECK_BINSEARCH 463#ifdef CHECK_BINSEARCH
431 { 464 {
@@ -468,11 +501,10 @@ ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path)
468 short int depth, i, ppos = 0, alloc = 0; 501 short int depth, i, ppos = 0, alloc = 0;
469 502
470 eh = ext_inode_hdr(inode); 503 eh = ext_inode_hdr(inode);
471 BUG_ON(eh == NULL); 504 depth = ext_depth(inode);
472 if (ext4_ext_check_header(__FUNCTION__, inode, eh)) 505 if (ext4_ext_check_header(inode, eh, depth))
473 return ERR_PTR(-EIO); 506 return ERR_PTR(-EIO);
474 507
475 i = depth = ext_depth(inode);
476 508
477 /* account possible depth increase */ 509 /* account possible depth increase */
478 if (!path) { 510 if (!path) {
@@ -484,10 +516,12 @@ ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path)
484 } 516 }
485 path[0].p_hdr = eh; 517 path[0].p_hdr = eh;
486 518
519 i = depth;
487 /* walk through the tree */ 520 /* walk through the tree */
488 while (i) { 521 while (i) {
489 ext_debug("depth %d: num %d, max %d\n", 522 ext_debug("depth %d: num %d, max %d\n",
490 ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max)); 523 ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
524
491 ext4_ext_binsearch_idx(inode, path + ppos, block); 525 ext4_ext_binsearch_idx(inode, path + ppos, block);
492 path[ppos].p_block = idx_pblock(path[ppos].p_idx); 526 path[ppos].p_block = idx_pblock(path[ppos].p_idx);
493 path[ppos].p_depth = i; 527 path[ppos].p_depth = i;
@@ -504,7 +538,7 @@ ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path)
504 path[ppos].p_hdr = eh; 538 path[ppos].p_hdr = eh;
505 i--; 539 i--;
506 540
507 if (ext4_ext_check_header(__FUNCTION__, inode, eh)) 541 if (ext4_ext_check_header(inode, eh, i))
508 goto err; 542 goto err;
509 } 543 }
510 544
@@ -513,9 +547,6 @@ ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path)
513 path[ppos].p_ext = NULL; 547 path[ppos].p_ext = NULL;
514 path[ppos].p_idx = NULL; 548 path[ppos].p_idx = NULL;
515 549
516 if (ext4_ext_check_header(__FUNCTION__, inode, eh))
517 goto err;
518
519 /* find extent */ 550 /* find extent */
520 ext4_ext_binsearch(inode, path + ppos, block); 551 ext4_ext_binsearch(inode, path + ppos, block);
521 552
@@ -553,7 +584,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
553 if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) { 584 if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
554 len = (len - 1) * sizeof(struct ext4_extent_idx); 585 len = (len - 1) * sizeof(struct ext4_extent_idx);
555 len = len < 0 ? 0 : len; 586 len = len < 0 ? 0 : len;
556 ext_debug("insert new index %d after: %d. " 587 ext_debug("insert new index %d after: %llu. "
557 "move %d from 0x%p to 0x%p\n", 588 "move %d from 0x%p to 0x%p\n",
558 logical, ptr, len, 589 logical, ptr, len,
559 (curp->p_idx + 1), (curp->p_idx + 2)); 590 (curp->p_idx + 1), (curp->p_idx + 2));
@@ -564,7 +595,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
564 /* insert before */ 595 /* insert before */
565 len = len * sizeof(struct ext4_extent_idx); 596 len = len * sizeof(struct ext4_extent_idx);
566 len = len < 0 ? 0 : len; 597 len = len < 0 ? 0 : len;
567 ext_debug("insert new index %d before: %d. " 598 ext_debug("insert new index %d before: %llu. "
568 "move %d from 0x%p to 0x%p\n", 599 "move %d from 0x%p to 0x%p\n",
569 logical, ptr, len, 600 logical, ptr, len,
570 curp->p_idx, (curp->p_idx + 1)); 601 curp->p_idx, (curp->p_idx + 1));
@@ -686,7 +717,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
686 ext_debug("move %d:%llu:%d in new leaf %llu\n", 717 ext_debug("move %d:%llu:%d in new leaf %llu\n",
687 le32_to_cpu(path[depth].p_ext->ee_block), 718 le32_to_cpu(path[depth].p_ext->ee_block),
688 ext_pblock(path[depth].p_ext), 719 ext_pblock(path[depth].p_ext),
689 le16_to_cpu(path[depth].p_ext->ee_len), 720 ext4_ext_get_actual_len(path[depth].p_ext),
690 newblock); 721 newblock);
691 /*memmove(ex++, path[depth].p_ext++, 722 /*memmove(ex++, path[depth].p_ext++,
692 sizeof(struct ext4_extent)); 723 sizeof(struct ext4_extent));
@@ -764,7 +795,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
764 BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) != 795 BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) !=
765 EXT_LAST_INDEX(path[i].p_hdr)); 796 EXT_LAST_INDEX(path[i].p_hdr));
766 while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) { 797 while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
767 ext_debug("%d: move %d:%d in new index %llu\n", i, 798 ext_debug("%d: move %d:%llu in new index %llu\n", i,
768 le32_to_cpu(path[i].p_idx->ei_block), 799 le32_to_cpu(path[i].p_idx->ei_block),
769 idx_pblock(path[i].p_idx), 800 idx_pblock(path[i].p_idx),
770 newblock); 801 newblock);
@@ -893,8 +924,13 @@ static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
893 curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode)); 924 curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode));
894 curp->p_hdr->eh_entries = cpu_to_le16(1); 925 curp->p_hdr->eh_entries = cpu_to_le16(1);
895 curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr); 926 curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
896 /* FIXME: it works, but actually path[0] can be index */ 927
897 curp->p_idx->ei_block = EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block; 928 if (path[0].p_hdr->eh_depth)
929 curp->p_idx->ei_block =
930 EXT_FIRST_INDEX(path[0].p_hdr)->ei_block;
931 else
932 curp->p_idx->ei_block =
933 EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
898 ext4_idx_store_pblock(curp->p_idx, newblock); 934 ext4_idx_store_pblock(curp->p_idx, newblock);
899 935
900 neh = ext_inode_hdr(inode); 936 neh = ext_inode_hdr(inode);
@@ -1106,7 +1142,24 @@ static int
1106ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, 1142ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
1107 struct ext4_extent *ex2) 1143 struct ext4_extent *ex2)
1108{ 1144{
1109 if (le32_to_cpu(ex1->ee_block) + le16_to_cpu(ex1->ee_len) != 1145 unsigned short ext1_ee_len, ext2_ee_len, max_len;
1146
1147 /*
1148 * Make sure that either both extents are uninitialized, or
1149 * both are _not_.
1150 */
1151 if (ext4_ext_is_uninitialized(ex1) ^ ext4_ext_is_uninitialized(ex2))
1152 return 0;
1153
1154 if (ext4_ext_is_uninitialized(ex1))
1155 max_len = EXT_UNINIT_MAX_LEN;
1156 else
1157 max_len = EXT_INIT_MAX_LEN;
1158
1159 ext1_ee_len = ext4_ext_get_actual_len(ex1);
1160 ext2_ee_len = ext4_ext_get_actual_len(ex2);
1161
1162 if (le32_to_cpu(ex1->ee_block) + ext1_ee_len !=
1110 le32_to_cpu(ex2->ee_block)) 1163 le32_to_cpu(ex2->ee_block))
1111 return 0; 1164 return 0;
1112 1165
@@ -1115,19 +1168,66 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
1115 * as an RO_COMPAT feature, refuse to merge to extents if 1168 * as an RO_COMPAT feature, refuse to merge to extents if
1116 * this can result in the top bit of ee_len being set. 1169 * this can result in the top bit of ee_len being set.
1117 */ 1170 */
1118 if (le16_to_cpu(ex1->ee_len) + le16_to_cpu(ex2->ee_len) > EXT_MAX_LEN) 1171 if (ext1_ee_len + ext2_ee_len > max_len)
1119 return 0; 1172 return 0;
1120#ifdef AGGRESSIVE_TEST 1173#ifdef AGGRESSIVE_TEST
1121 if (le16_to_cpu(ex1->ee_len) >= 4) 1174 if (le16_to_cpu(ex1->ee_len) >= 4)
1122 return 0; 1175 return 0;
1123#endif 1176#endif
1124 1177
1125 if (ext_pblock(ex1) + le16_to_cpu(ex1->ee_len) == ext_pblock(ex2)) 1178 if (ext_pblock(ex1) + ext1_ee_len == ext_pblock(ex2))
1126 return 1; 1179 return 1;
1127 return 0; 1180 return 0;
1128} 1181}
1129 1182
1130/* 1183/*
1184 * This function tries to merge the "ex" extent to the next extent in the tree.
1185 * It always tries to merge towards right. If you want to merge towards
1186 * left, pass "ex - 1" as argument instead of "ex".
1187 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1188 * 1 if they got merged.
1189 */
1190int ext4_ext_try_to_merge(struct inode *inode,
1191 struct ext4_ext_path *path,
1192 struct ext4_extent *ex)
1193{
1194 struct ext4_extent_header *eh;
1195 unsigned int depth, len;
1196 int merge_done = 0;
1197 int uninitialized = 0;
1198
1199 depth = ext_depth(inode);
1200 BUG_ON(path[depth].p_hdr == NULL);
1201 eh = path[depth].p_hdr;
1202
1203 while (ex < EXT_LAST_EXTENT(eh)) {
1204 if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
1205 break;
1206 /* merge with next extent! */
1207 if (ext4_ext_is_uninitialized(ex))
1208 uninitialized = 1;
1209 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1210 + ext4_ext_get_actual_len(ex + 1));
1211 if (uninitialized)
1212 ext4_ext_mark_uninitialized(ex);
1213
1214 if (ex + 1 < EXT_LAST_EXTENT(eh)) {
1215 len = (EXT_LAST_EXTENT(eh) - ex - 1)
1216 * sizeof(struct ext4_extent);
1217 memmove(ex + 1, ex + 2, len);
1218 }
1219 eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries) - 1);
1220 merge_done = 1;
1221 WARN_ON(eh->eh_entries == 0);
1222 if (!eh->eh_entries)
1223 ext4_error(inode->i_sb, "ext4_ext_try_to_merge",
1224 "inode#%lu, eh->eh_entries = 0!", inode->i_ino);
1225 }
1226
1227 return merge_done;
1228}
1229
1230/*
1131 * check if a portion of the "newext" extent overlaps with an 1231 * check if a portion of the "newext" extent overlaps with an
1132 * existing extent. 1232 * existing extent.
1133 * 1233 *
@@ -1144,7 +1244,7 @@ unsigned int ext4_ext_check_overlap(struct inode *inode,
1144 unsigned int ret = 0; 1244 unsigned int ret = 0;
1145 1245
1146 b1 = le32_to_cpu(newext->ee_block); 1246 b1 = le32_to_cpu(newext->ee_block);
1147 len1 = le16_to_cpu(newext->ee_len); 1247 len1 = ext4_ext_get_actual_len(newext);
1148 depth = ext_depth(inode); 1248 depth = ext_depth(inode);
1149 if (!path[depth].p_ext) 1249 if (!path[depth].p_ext)
1150 goto out; 1250 goto out;
@@ -1191,8 +1291,9 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
1191 struct ext4_extent *nearex; /* nearest extent */ 1291 struct ext4_extent *nearex; /* nearest extent */
1192 struct ext4_ext_path *npath = NULL; 1292 struct ext4_ext_path *npath = NULL;
1193 int depth, len, err, next; 1293 int depth, len, err, next;
1294 unsigned uninitialized = 0;
1194 1295
1195 BUG_ON(newext->ee_len == 0); 1296 BUG_ON(ext4_ext_get_actual_len(newext) == 0);
1196 depth = ext_depth(inode); 1297 depth = ext_depth(inode);
1197 ex = path[depth].p_ext; 1298 ex = path[depth].p_ext;
1198 BUG_ON(path[depth].p_hdr == NULL); 1299 BUG_ON(path[depth].p_hdr == NULL);
@@ -1200,14 +1301,24 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
1200 /* try to insert block into found extent and return */ 1301 /* try to insert block into found extent and return */
1201 if (ex && ext4_can_extents_be_merged(inode, ex, newext)) { 1302 if (ex && ext4_can_extents_be_merged(inode, ex, newext)) {
1202 ext_debug("append %d block to %d:%d (from %llu)\n", 1303 ext_debug("append %d block to %d:%d (from %llu)\n",
1203 le16_to_cpu(newext->ee_len), 1304 ext4_ext_get_actual_len(newext),
1204 le32_to_cpu(ex->ee_block), 1305 le32_to_cpu(ex->ee_block),
1205 le16_to_cpu(ex->ee_len), ext_pblock(ex)); 1306 ext4_ext_get_actual_len(ex), ext_pblock(ex));
1206 err = ext4_ext_get_access(handle, inode, path + depth); 1307 err = ext4_ext_get_access(handle, inode, path + depth);
1207 if (err) 1308 if (err)
1208 return err; 1309 return err;
1209 ex->ee_len = cpu_to_le16(le16_to_cpu(ex->ee_len) 1310
1210 + le16_to_cpu(newext->ee_len)); 1311 /*
1312 * ext4_can_extents_be_merged should have checked that either
1313 * both extents are uninitialized, or both aren't. Thus we
1314 * need to check only one of them here.
1315 */
1316 if (ext4_ext_is_uninitialized(ex))
1317 uninitialized = 1;
1318 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1319 + ext4_ext_get_actual_len(newext));
1320 if (uninitialized)
1321 ext4_ext_mark_uninitialized(ex);
1211 eh = path[depth].p_hdr; 1322 eh = path[depth].p_hdr;
1212 nearex = ex; 1323 nearex = ex;
1213 goto merge; 1324 goto merge;
@@ -1263,7 +1374,7 @@ has_space:
1263 ext_debug("first extent in the leaf: %d:%llu:%d\n", 1374 ext_debug("first extent in the leaf: %d:%llu:%d\n",
1264 le32_to_cpu(newext->ee_block), 1375 le32_to_cpu(newext->ee_block),
1265 ext_pblock(newext), 1376 ext_pblock(newext),
1266 le16_to_cpu(newext->ee_len)); 1377 ext4_ext_get_actual_len(newext));
1267 path[depth].p_ext = EXT_FIRST_EXTENT(eh); 1378 path[depth].p_ext = EXT_FIRST_EXTENT(eh);
1268 } else if (le32_to_cpu(newext->ee_block) 1379 } else if (le32_to_cpu(newext->ee_block)
1269 > le32_to_cpu(nearex->ee_block)) { 1380 > le32_to_cpu(nearex->ee_block)) {
@@ -1276,7 +1387,7 @@ has_space:
1276 "move %d from 0x%p to 0x%p\n", 1387 "move %d from 0x%p to 0x%p\n",
1277 le32_to_cpu(newext->ee_block), 1388 le32_to_cpu(newext->ee_block),
1278 ext_pblock(newext), 1389 ext_pblock(newext),
1279 le16_to_cpu(newext->ee_len), 1390 ext4_ext_get_actual_len(newext),
1280 nearex, len, nearex + 1, nearex + 2); 1391 nearex, len, nearex + 1, nearex + 2);
1281 memmove(nearex + 2, nearex + 1, len); 1392 memmove(nearex + 2, nearex + 1, len);
1282 } 1393 }
@@ -1289,7 +1400,7 @@ has_space:
1289 "move %d from 0x%p to 0x%p\n", 1400 "move %d from 0x%p to 0x%p\n",
1290 le32_to_cpu(newext->ee_block), 1401 le32_to_cpu(newext->ee_block),
1291 ext_pblock(newext), 1402 ext_pblock(newext),
1292 le16_to_cpu(newext->ee_len), 1403 ext4_ext_get_actual_len(newext),
1293 nearex, len, nearex + 1, nearex + 2); 1404 nearex, len, nearex + 1, nearex + 2);
1294 memmove(nearex + 1, nearex, len); 1405 memmove(nearex + 1, nearex, len);
1295 path[depth].p_ext = nearex; 1406 path[depth].p_ext = nearex;
@@ -1304,20 +1415,7 @@ has_space:
1304 1415
1305merge: 1416merge:
1306 /* try to merge extents to the right */ 1417 /* try to merge extents to the right */
1307 while (nearex < EXT_LAST_EXTENT(eh)) { 1418 ext4_ext_try_to_merge(inode, path, nearex);
1308 if (!ext4_can_extents_be_merged(inode, nearex, nearex + 1))
1309 break;
1310 /* merge with next extent! */
1311 nearex->ee_len = cpu_to_le16(le16_to_cpu(nearex->ee_len)
1312 + le16_to_cpu(nearex[1].ee_len));
1313 if (nearex + 1 < EXT_LAST_EXTENT(eh)) {
1314 len = (EXT_LAST_EXTENT(eh) - nearex - 1)
1315 * sizeof(struct ext4_extent);
1316 memmove(nearex + 1, nearex + 2, len);
1317 }
1318 eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
1319 BUG_ON(eh->eh_entries == 0);
1320 }
1321 1419
1322 /* try to merge extents to the left */ 1420 /* try to merge extents to the left */
1323 1421
@@ -1379,8 +1477,8 @@ int ext4_ext_walk_space(struct inode *inode, unsigned long block,
1379 end = le32_to_cpu(ex->ee_block); 1477 end = le32_to_cpu(ex->ee_block);
1380 if (block + num < end) 1478 if (block + num < end)
1381 end = block + num; 1479 end = block + num;
1382 } else if (block >= 1480 } else if (block >= le32_to_cpu(ex->ee_block)
1383 le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len)) { 1481 + ext4_ext_get_actual_len(ex)) {
1384 /* need to allocate space after found extent */ 1482 /* need to allocate space after found extent */
1385 start = block; 1483 start = block;
1386 end = block + num; 1484 end = block + num;
@@ -1392,7 +1490,8 @@ int ext4_ext_walk_space(struct inode *inode, unsigned long block,
1392 * by found extent 1490 * by found extent
1393 */ 1491 */
1394 start = block; 1492 start = block;
1395 end = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len); 1493 end = le32_to_cpu(ex->ee_block)
1494 + ext4_ext_get_actual_len(ex);
1396 if (block + num < end) 1495 if (block + num < end)
1397 end = block + num; 1496 end = block + num;
1398 exists = 1; 1497 exists = 1;
@@ -1408,7 +1507,7 @@ int ext4_ext_walk_space(struct inode *inode, unsigned long block,
1408 cbex.ec_type = EXT4_EXT_CACHE_GAP; 1507 cbex.ec_type = EXT4_EXT_CACHE_GAP;
1409 } else { 1508 } else {
1410 cbex.ec_block = le32_to_cpu(ex->ee_block); 1509 cbex.ec_block = le32_to_cpu(ex->ee_block);
1411 cbex.ec_len = le16_to_cpu(ex->ee_len); 1510 cbex.ec_len = ext4_ext_get_actual_len(ex);
1412 cbex.ec_start = ext_pblock(ex); 1511 cbex.ec_start = ext_pblock(ex);
1413 cbex.ec_type = EXT4_EXT_CACHE_EXTENT; 1512 cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
1414 } 1513 }
@@ -1481,15 +1580,15 @@ ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
1481 ext_debug("cache gap(before): %lu [%lu:%lu]", 1580 ext_debug("cache gap(before): %lu [%lu:%lu]",
1482 (unsigned long) block, 1581 (unsigned long) block,
1483 (unsigned long) le32_to_cpu(ex->ee_block), 1582 (unsigned long) le32_to_cpu(ex->ee_block),
1484 (unsigned long) le16_to_cpu(ex->ee_len)); 1583 (unsigned long) ext4_ext_get_actual_len(ex));
1485 } else if (block >= le32_to_cpu(ex->ee_block) 1584 } else if (block >= le32_to_cpu(ex->ee_block)
1486 + le16_to_cpu(ex->ee_len)) { 1585 + ext4_ext_get_actual_len(ex)) {
1487 lblock = le32_to_cpu(ex->ee_block) 1586 lblock = le32_to_cpu(ex->ee_block)
1488 + le16_to_cpu(ex->ee_len); 1587 + ext4_ext_get_actual_len(ex);
1489 len = ext4_ext_next_allocated_block(path); 1588 len = ext4_ext_next_allocated_block(path);
1490 ext_debug("cache gap(after): [%lu:%lu] %lu", 1589 ext_debug("cache gap(after): [%lu:%lu] %lu",
1491 (unsigned long) le32_to_cpu(ex->ee_block), 1590 (unsigned long) le32_to_cpu(ex->ee_block),
1492 (unsigned long) le16_to_cpu(ex->ee_len), 1591 (unsigned long) ext4_ext_get_actual_len(ex),
1493 (unsigned long) block); 1592 (unsigned long) block);
1494 BUG_ON(len == lblock); 1593 BUG_ON(len == lblock);
1495 len = len - lblock; 1594 len = len - lblock;
@@ -1619,12 +1718,12 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
1619 unsigned long from, unsigned long to) 1718 unsigned long from, unsigned long to)
1620{ 1719{
1621 struct buffer_head *bh; 1720 struct buffer_head *bh;
1721 unsigned short ee_len = ext4_ext_get_actual_len(ex);
1622 int i; 1722 int i;
1623 1723
1624#ifdef EXTENTS_STATS 1724#ifdef EXTENTS_STATS
1625 { 1725 {
1626 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 1726 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
1627 unsigned short ee_len = le16_to_cpu(ex->ee_len);
1628 spin_lock(&sbi->s_ext_stats_lock); 1727 spin_lock(&sbi->s_ext_stats_lock);
1629 sbi->s_ext_blocks += ee_len; 1728 sbi->s_ext_blocks += ee_len;
1630 sbi->s_ext_extents++; 1729 sbi->s_ext_extents++;
@@ -1638,12 +1737,12 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
1638 } 1737 }
1639#endif 1738#endif
1640 if (from >= le32_to_cpu(ex->ee_block) 1739 if (from >= le32_to_cpu(ex->ee_block)
1641 && to == le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) { 1740 && to == le32_to_cpu(ex->ee_block) + ee_len - 1) {
1642 /* tail removal */ 1741 /* tail removal */
1643 unsigned long num; 1742 unsigned long num;
1644 ext4_fsblk_t start; 1743 ext4_fsblk_t start;
1645 num = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - from; 1744 num = le32_to_cpu(ex->ee_block) + ee_len - from;
1646 start = ext_pblock(ex) + le16_to_cpu(ex->ee_len) - num; 1745 start = ext_pblock(ex) + ee_len - num;
1647 ext_debug("free last %lu blocks starting %llu\n", num, start); 1746 ext_debug("free last %lu blocks starting %llu\n", num, start);
1648 for (i = 0; i < num; i++) { 1747 for (i = 0; i < num; i++) {
1649 bh = sb_find_get_block(inode->i_sb, start + i); 1748 bh = sb_find_get_block(inode->i_sb, start + i);
@@ -1651,12 +1750,12 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
1651 } 1750 }
1652 ext4_free_blocks(handle, inode, start, num); 1751 ext4_free_blocks(handle, inode, start, num);
1653 } else if (from == le32_to_cpu(ex->ee_block) 1752 } else if (from == le32_to_cpu(ex->ee_block)
1654 && to <= le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) { 1753 && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
1655 printk("strange request: removal %lu-%lu from %u:%u\n", 1754 printk("strange request: removal %lu-%lu from %u:%u\n",
1656 from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len)); 1755 from, to, le32_to_cpu(ex->ee_block), ee_len);
1657 } else { 1756 } else {
1658 printk("strange request: removal(2) %lu-%lu from %u:%u\n", 1757 printk("strange request: removal(2) %lu-%lu from %u:%u\n",
1659 from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len)); 1758 from, to, le32_to_cpu(ex->ee_block), ee_len);
1660 } 1759 }
1661 return 0; 1760 return 0;
1662} 1761}
@@ -1671,21 +1770,23 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
1671 unsigned a, b, block, num; 1770 unsigned a, b, block, num;
1672 unsigned long ex_ee_block; 1771 unsigned long ex_ee_block;
1673 unsigned short ex_ee_len; 1772 unsigned short ex_ee_len;
1773 unsigned uninitialized = 0;
1674 struct ext4_extent *ex; 1774 struct ext4_extent *ex;
1675 1775
1776 /* the header must be checked already in ext4_ext_remove_space() */
1676 ext_debug("truncate since %lu in leaf\n", start); 1777 ext_debug("truncate since %lu in leaf\n", start);
1677 if (!path[depth].p_hdr) 1778 if (!path[depth].p_hdr)
1678 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh); 1779 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
1679 eh = path[depth].p_hdr; 1780 eh = path[depth].p_hdr;
1680 BUG_ON(eh == NULL); 1781 BUG_ON(eh == NULL);
1681 BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
1682 BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
1683 1782
1684 /* find where to start removing */ 1783 /* find where to start removing */
1685 ex = EXT_LAST_EXTENT(eh); 1784 ex = EXT_LAST_EXTENT(eh);
1686 1785
1687 ex_ee_block = le32_to_cpu(ex->ee_block); 1786 ex_ee_block = le32_to_cpu(ex->ee_block);
1688 ex_ee_len = le16_to_cpu(ex->ee_len); 1787 if (ext4_ext_is_uninitialized(ex))
1788 uninitialized = 1;
1789 ex_ee_len = ext4_ext_get_actual_len(ex);
1689 1790
1690 while (ex >= EXT_FIRST_EXTENT(eh) && 1791 while (ex >= EXT_FIRST_EXTENT(eh) &&
1691 ex_ee_block + ex_ee_len > start) { 1792 ex_ee_block + ex_ee_len > start) {
@@ -1753,6 +1854,12 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
1753 1854
1754 ex->ee_block = cpu_to_le32(block); 1855 ex->ee_block = cpu_to_le32(block);
1755 ex->ee_len = cpu_to_le16(num); 1856 ex->ee_len = cpu_to_le16(num);
1857 /*
1858 * Do not mark uninitialized if all the blocks in the
1859 * extent have been removed.
1860 */
1861 if (uninitialized && num)
1862 ext4_ext_mark_uninitialized(ex);
1756 1863
1757 err = ext4_ext_dirty(handle, inode, path + depth); 1864 err = ext4_ext_dirty(handle, inode, path + depth);
1758 if (err) 1865 if (err)
@@ -1762,7 +1869,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
1762 ext_pblock(ex)); 1869 ext_pblock(ex));
1763 ex--; 1870 ex--;
1764 ex_ee_block = le32_to_cpu(ex->ee_block); 1871 ex_ee_block = le32_to_cpu(ex->ee_block);
1765 ex_ee_len = le16_to_cpu(ex->ee_len); 1872 ex_ee_len = ext4_ext_get_actual_len(ex);
1766 } 1873 }
1767 1874
1768 if (correct_index && eh->eh_entries) 1875 if (correct_index && eh->eh_entries)
@@ -1825,7 +1932,7 @@ int ext4_ext_remove_space(struct inode *inode, unsigned long start)
1825 return -ENOMEM; 1932 return -ENOMEM;
1826 } 1933 }
1827 path[0].p_hdr = ext_inode_hdr(inode); 1934 path[0].p_hdr = ext_inode_hdr(inode);
1828 if (ext4_ext_check_header(__FUNCTION__, inode, path[0].p_hdr)) { 1935 if (ext4_ext_check_header(inode, path[0].p_hdr, depth)) {
1829 err = -EIO; 1936 err = -EIO;
1830 goto out; 1937 goto out;
1831 } 1938 }
@@ -1846,17 +1953,8 @@ int ext4_ext_remove_space(struct inode *inode, unsigned long start)
1846 if (!path[i].p_hdr) { 1953 if (!path[i].p_hdr) {
1847 ext_debug("initialize header\n"); 1954 ext_debug("initialize header\n");
1848 path[i].p_hdr = ext_block_hdr(path[i].p_bh); 1955 path[i].p_hdr = ext_block_hdr(path[i].p_bh);
1849 if (ext4_ext_check_header(__FUNCTION__, inode,
1850 path[i].p_hdr)) {
1851 err = -EIO;
1852 goto out;
1853 }
1854 } 1956 }
1855 1957
1856 BUG_ON(le16_to_cpu(path[i].p_hdr->eh_entries)
1857 > le16_to_cpu(path[i].p_hdr->eh_max));
1858 BUG_ON(path[i].p_hdr->eh_magic != EXT4_EXT_MAGIC);
1859
1860 if (!path[i].p_idx) { 1958 if (!path[i].p_idx) {
1861 /* this level hasn't been touched yet */ 1959 /* this level hasn't been touched yet */
1862 path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr); 1960 path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
@@ -1873,17 +1971,27 @@ int ext4_ext_remove_space(struct inode *inode, unsigned long start)
1873 i, EXT_FIRST_INDEX(path[i].p_hdr), 1971 i, EXT_FIRST_INDEX(path[i].p_hdr),
1874 path[i].p_idx); 1972 path[i].p_idx);
1875 if (ext4_ext_more_to_rm(path + i)) { 1973 if (ext4_ext_more_to_rm(path + i)) {
1974 struct buffer_head *bh;
1876 /* go to the next level */ 1975 /* go to the next level */
1877 ext_debug("move to level %d (block %llu)\n", 1976 ext_debug("move to level %d (block %llu)\n",
1878 i + 1, idx_pblock(path[i].p_idx)); 1977 i + 1, idx_pblock(path[i].p_idx));
1879 memset(path + i + 1, 0, sizeof(*path)); 1978 memset(path + i + 1, 0, sizeof(*path));
1880 path[i+1].p_bh = 1979 bh = sb_bread(sb, idx_pblock(path[i].p_idx));
1881 sb_bread(sb, idx_pblock(path[i].p_idx)); 1980 if (!bh) {
1882 if (!path[i+1].p_bh) {
1883 /* should we reset i_size? */ 1981 /* should we reset i_size? */
1884 err = -EIO; 1982 err = -EIO;
1885 break; 1983 break;
1886 } 1984 }
1985 if (WARN_ON(i + 1 > depth)) {
1986 err = -EIO;
1987 break;
1988 }
1989 if (ext4_ext_check_header(inode, ext_block_hdr(bh),
1990 depth - i - 1)) {
1991 err = -EIO;
1992 break;
1993 }
1994 path[i + 1].p_bh = bh;
1887 1995
1888 /* save actual number of indexes since this 1996 /* save actual number of indexes since this
1889 * number is changed at the next iteration */ 1997 * number is changed at the next iteration */
@@ -1977,15 +2085,158 @@ void ext4_ext_release(struct super_block *sb)
1977#endif 2085#endif
1978} 2086}
1979 2087
2088/*
2089 * This function is called by ext4_ext_get_blocks() if someone tries to write
2090 * to an uninitialized extent. It may result in splitting the uninitialized
2091 * extent into multiple extents (upto three - one initialized and two
2092 * uninitialized).
2093 * There are three possibilities:
2094 * a> There is no split required: Entire extent should be initialized
2095 * b> Splits in two extents: Write is happening at either end of the extent
2096 * c> Splits in three extents: Somone is writing in middle of the extent
2097 */
2098int ext4_ext_convert_to_initialized(handle_t *handle, struct inode *inode,
2099 struct ext4_ext_path *path,
2100 ext4_fsblk_t iblock,
2101 unsigned long max_blocks)
2102{
2103 struct ext4_extent *ex, newex;
2104 struct ext4_extent *ex1 = NULL;
2105 struct ext4_extent *ex2 = NULL;
2106 struct ext4_extent *ex3 = NULL;
2107 struct ext4_extent_header *eh;
2108 unsigned int allocated, ee_block, ee_len, depth;
2109 ext4_fsblk_t newblock;
2110 int err = 0;
2111 int ret = 0;
2112
2113 depth = ext_depth(inode);
2114 eh = path[depth].p_hdr;
2115 ex = path[depth].p_ext;
2116 ee_block = le32_to_cpu(ex->ee_block);
2117 ee_len = ext4_ext_get_actual_len(ex);
2118 allocated = ee_len - (iblock - ee_block);
2119 newblock = iblock - ee_block + ext_pblock(ex);
2120 ex2 = ex;
2121
2122 /* ex1: ee_block to iblock - 1 : uninitialized */
2123 if (iblock > ee_block) {
2124 ex1 = ex;
2125 ex1->ee_len = cpu_to_le16(iblock - ee_block);
2126 ext4_ext_mark_uninitialized(ex1);
2127 ex2 = &newex;
2128 }
2129 /*
2130 * for sanity, update the length of the ex2 extent before
2131 * we insert ex3, if ex1 is NULL. This is to avoid temporary
2132 * overlap of blocks.
2133 */
2134 if (!ex1 && allocated > max_blocks)
2135 ex2->ee_len = cpu_to_le16(max_blocks);
2136 /* ex3: to ee_block + ee_len : uninitialised */
2137 if (allocated > max_blocks) {
2138 unsigned int newdepth;
2139 ex3 = &newex;
2140 ex3->ee_block = cpu_to_le32(iblock + max_blocks);
2141 ext4_ext_store_pblock(ex3, newblock + max_blocks);
2142 ex3->ee_len = cpu_to_le16(allocated - max_blocks);
2143 ext4_ext_mark_uninitialized(ex3);
2144 err = ext4_ext_insert_extent(handle, inode, path, ex3);
2145 if (err)
2146 goto out;
2147 /*
2148 * The depth, and hence eh & ex might change
2149 * as part of the insert above.
2150 */
2151 newdepth = ext_depth(inode);
2152 if (newdepth != depth) {
2153 depth = newdepth;
2154 path = ext4_ext_find_extent(inode, iblock, NULL);
2155 if (IS_ERR(path)) {
2156 err = PTR_ERR(path);
2157 path = NULL;
2158 goto out;
2159 }
2160 eh = path[depth].p_hdr;
2161 ex = path[depth].p_ext;
2162 if (ex2 != &newex)
2163 ex2 = ex;
2164 }
2165 allocated = max_blocks;
2166 }
2167 /*
2168 * If there was a change of depth as part of the
2169 * insertion of ex3 above, we need to update the length
2170 * of the ex1 extent again here
2171 */
2172 if (ex1 && ex1 != ex) {
2173 ex1 = ex;
2174 ex1->ee_len = cpu_to_le16(iblock - ee_block);
2175 ext4_ext_mark_uninitialized(ex1);
2176 ex2 = &newex;
2177 }
2178 /* ex2: iblock to iblock + maxblocks-1 : initialised */
2179 ex2->ee_block = cpu_to_le32(iblock);
2180 ex2->ee_start = cpu_to_le32(newblock);
2181 ext4_ext_store_pblock(ex2, newblock);
2182 ex2->ee_len = cpu_to_le16(allocated);
2183 if (ex2 != ex)
2184 goto insert;
2185 err = ext4_ext_get_access(handle, inode, path + depth);
2186 if (err)
2187 goto out;
2188 /*
2189 * New (initialized) extent starts from the first block
2190 * in the current extent. i.e., ex2 == ex
2191 * We have to see if it can be merged with the extent
2192 * on the left.
2193 */
2194 if (ex2 > EXT_FIRST_EXTENT(eh)) {
2195 /*
2196 * To merge left, pass "ex2 - 1" to try_to_merge(),
2197 * since it merges towards right _only_.
2198 */
2199 ret = ext4_ext_try_to_merge(inode, path, ex2 - 1);
2200 if (ret) {
2201 err = ext4_ext_correct_indexes(handle, inode, path);
2202 if (err)
2203 goto out;
2204 depth = ext_depth(inode);
2205 ex2--;
2206 }
2207 }
2208 /*
2209 * Try to Merge towards right. This might be required
2210 * only when the whole extent is being written to.
2211 * i.e. ex2 == ex and ex3 == NULL.
2212 */
2213 if (!ex3) {
2214 ret = ext4_ext_try_to_merge(inode, path, ex2);
2215 if (ret) {
2216 err = ext4_ext_correct_indexes(handle, inode, path);
2217 if (err)
2218 goto out;
2219 }
2220 }
2221 /* Mark modified extent as dirty */
2222 err = ext4_ext_dirty(handle, inode, path + depth);
2223 goto out;
2224insert:
2225 err = ext4_ext_insert_extent(handle, inode, path, &newex);
2226out:
2227 return err ? err : allocated;
2228}
2229
1980int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, 2230int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
1981 ext4_fsblk_t iblock, 2231 ext4_fsblk_t iblock,
1982 unsigned long max_blocks, struct buffer_head *bh_result, 2232 unsigned long max_blocks, struct buffer_head *bh_result,
1983 int create, int extend_disksize) 2233 int create, int extend_disksize)
1984{ 2234{
1985 struct ext4_ext_path *path = NULL; 2235 struct ext4_ext_path *path = NULL;
2236 struct ext4_extent_header *eh;
1986 struct ext4_extent newex, *ex; 2237 struct ext4_extent newex, *ex;
1987 ext4_fsblk_t goal, newblock; 2238 ext4_fsblk_t goal, newblock;
1988 int err = 0, depth; 2239 int err = 0, depth, ret;
1989 unsigned long allocated = 0; 2240 unsigned long allocated = 0;
1990 2241
1991 __clear_bit(BH_New, &bh_result->b_state); 2242 __clear_bit(BH_New, &bh_result->b_state);
@@ -1998,8 +2249,10 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
1998 if (goal) { 2249 if (goal) {
1999 if (goal == EXT4_EXT_CACHE_GAP) { 2250 if (goal == EXT4_EXT_CACHE_GAP) {
2000 if (!create) { 2251 if (!create) {
2001 /* block isn't allocated yet and 2252 /*
2002 * user doesn't want to allocate it */ 2253 * block isn't allocated yet and
2254 * user doesn't want to allocate it
2255 */
2003 goto out2; 2256 goto out2;
2004 } 2257 }
2005 /* we should allocate requested block */ 2258 /* we should allocate requested block */
@@ -2033,21 +2286,19 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
2033 * this is why assert can't be put in ext4_ext_find_extent() 2286 * this is why assert can't be put in ext4_ext_find_extent()
2034 */ 2287 */
2035 BUG_ON(path[depth].p_ext == NULL && depth != 0); 2288 BUG_ON(path[depth].p_ext == NULL && depth != 0);
2289 eh = path[depth].p_hdr;
2036 2290
2037 ex = path[depth].p_ext; 2291 ex = path[depth].p_ext;
2038 if (ex) { 2292 if (ex) {
2039 unsigned long ee_block = le32_to_cpu(ex->ee_block); 2293 unsigned long ee_block = le32_to_cpu(ex->ee_block);
2040 ext4_fsblk_t ee_start = ext_pblock(ex); 2294 ext4_fsblk_t ee_start = ext_pblock(ex);
2041 unsigned short ee_len = le16_to_cpu(ex->ee_len); 2295 unsigned short ee_len;
2042 2296
2043 /* 2297 /*
2044 * Allow future support for preallocated extents to be added
2045 * as an RO_COMPAT feature:
2046 * Uninitialized extents are treated as holes, except that 2298 * Uninitialized extents are treated as holes, except that
2047 * we avoid (fail) allocating new blocks during a write. 2299 * we split out initialized portions during a write.
2048 */ 2300 */
2049 if (ee_len > EXT_MAX_LEN) 2301 ee_len = ext4_ext_get_actual_len(ex);
2050 goto out2;
2051 /* if found extent covers block, simply return it */ 2302 /* if found extent covers block, simply return it */
2052 if (iblock >= ee_block && iblock < ee_block + ee_len) { 2303 if (iblock >= ee_block && iblock < ee_block + ee_len) {
2053 newblock = iblock - ee_block + ee_start; 2304 newblock = iblock - ee_block + ee_start;
@@ -2055,9 +2306,27 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
2055 allocated = ee_len - (iblock - ee_block); 2306 allocated = ee_len - (iblock - ee_block);
2056 ext_debug("%d fit into %lu:%d -> %llu\n", (int) iblock, 2307 ext_debug("%d fit into %lu:%d -> %llu\n", (int) iblock,
2057 ee_block, ee_len, newblock); 2308 ee_block, ee_len, newblock);
2058 ext4_ext_put_in_cache(inode, ee_block, ee_len, 2309
2059 ee_start, EXT4_EXT_CACHE_EXTENT); 2310 /* Do not put uninitialized extent in the cache */
2060 goto out; 2311 if (!ext4_ext_is_uninitialized(ex)) {
2312 ext4_ext_put_in_cache(inode, ee_block,
2313 ee_len, ee_start,
2314 EXT4_EXT_CACHE_EXTENT);
2315 goto out;
2316 }
2317 if (create == EXT4_CREATE_UNINITIALIZED_EXT)
2318 goto out;
2319 if (!create)
2320 goto out2;
2321
2322 ret = ext4_ext_convert_to_initialized(handle, inode,
2323 path, iblock,
2324 max_blocks);
2325 if (ret <= 0)
2326 goto out2;
2327 else
2328 allocated = ret;
2329 goto outnew;
2061 } 2330 }
2062 } 2331 }
2063 2332
@@ -2066,8 +2335,10 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
2066 * we couldn't try to create block if create flag is zero 2335 * we couldn't try to create block if create flag is zero
2067 */ 2336 */
2068 if (!create) { 2337 if (!create) {
2069 /* put just found gap into cache to speed up 2338 /*
2070 * subsequent requests */ 2339 * put just found gap into cache to speed up
2340 * subsequent requests
2341 */
2071 ext4_ext_put_gap_in_cache(inode, path, iblock); 2342 ext4_ext_put_gap_in_cache(inode, path, iblock);
2072 goto out2; 2343 goto out2;
2073 } 2344 }
@@ -2081,6 +2352,19 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
2081 /* allocate new block */ 2352 /* allocate new block */
2082 goal = ext4_ext_find_goal(inode, path, iblock); 2353 goal = ext4_ext_find_goal(inode, path, iblock);
2083 2354
2355 /*
2356 * See if request is beyond maximum number of blocks we can have in
2357 * a single extent. For an initialized extent this limit is
2358 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
2359 * EXT_UNINIT_MAX_LEN.
2360 */
2361 if (max_blocks > EXT_INIT_MAX_LEN &&
2362 create != EXT4_CREATE_UNINITIALIZED_EXT)
2363 max_blocks = EXT_INIT_MAX_LEN;
2364 else if (max_blocks > EXT_UNINIT_MAX_LEN &&
2365 create == EXT4_CREATE_UNINITIALIZED_EXT)
2366 max_blocks = EXT_UNINIT_MAX_LEN;
2367
2084 /* Check if we can really insert (iblock)::(iblock+max_blocks) extent */ 2368 /* Check if we can really insert (iblock)::(iblock+max_blocks) extent */
2085 newex.ee_block = cpu_to_le32(iblock); 2369 newex.ee_block = cpu_to_le32(iblock);
2086 newex.ee_len = cpu_to_le16(max_blocks); 2370 newex.ee_len = cpu_to_le16(max_blocks);
@@ -2098,6 +2382,8 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
2098 /* try to insert new extent into found leaf and return */ 2382 /* try to insert new extent into found leaf and return */
2099 ext4_ext_store_pblock(&newex, newblock); 2383 ext4_ext_store_pblock(&newex, newblock);
2100 newex.ee_len = cpu_to_le16(allocated); 2384 newex.ee_len = cpu_to_le16(allocated);
2385 if (create == EXT4_CREATE_UNINITIALIZED_EXT) /* Mark uninitialized */
2386 ext4_ext_mark_uninitialized(&newex);
2101 err = ext4_ext_insert_extent(handle, inode, path, &newex); 2387 err = ext4_ext_insert_extent(handle, inode, path, &newex);
2102 if (err) { 2388 if (err) {
2103 /* free data blocks we just allocated */ 2389 /* free data blocks we just allocated */
@@ -2111,10 +2397,13 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
2111 2397
2112 /* previous routine could use block we allocated */ 2398 /* previous routine could use block we allocated */
2113 newblock = ext_pblock(&newex); 2399 newblock = ext_pblock(&newex);
2400outnew:
2114 __set_bit(BH_New, &bh_result->b_state); 2401 __set_bit(BH_New, &bh_result->b_state);
2115 2402
2116 ext4_ext_put_in_cache(inode, iblock, allocated, newblock, 2403 /* Cache only when it is _not_ an uninitialized extent */
2117 EXT4_EXT_CACHE_EXTENT); 2404 if (create != EXT4_CREATE_UNINITIALIZED_EXT)
2405 ext4_ext_put_in_cache(inode, iblock, allocated, newblock,
2406 EXT4_EXT_CACHE_EXTENT);
2118out: 2407out:
2119 if (allocated > max_blocks) 2408 if (allocated > max_blocks)
2120 allocated = max_blocks; 2409 allocated = max_blocks;
@@ -2178,7 +2467,8 @@ void ext4_ext_truncate(struct inode * inode, struct page *page)
2178 err = ext4_ext_remove_space(inode, last_block); 2467 err = ext4_ext_remove_space(inode, last_block);
2179 2468
2180 /* In a multi-transaction truncate, we only make the final 2469 /* In a multi-transaction truncate, we only make the final
2181 * transaction synchronous. */ 2470 * transaction synchronous.
2471 */
2182 if (IS_SYNC(inode)) 2472 if (IS_SYNC(inode))
2183 handle->h_sync = 1; 2473 handle->h_sync = 1;
2184 2474
@@ -2217,3 +2507,127 @@ int ext4_ext_writepage_trans_blocks(struct inode *inode, int num)
2217 2507
2218 return needed; 2508 return needed;
2219} 2509}
2510
2511/*
2512 * preallocate space for a file. This implements ext4's fallocate inode
2513 * operation, which gets called from sys_fallocate system call.
2514 * For block-mapped files, posix_fallocate should fall back to the method
2515 * of writing zeroes to the required new blocks (the same behavior which is
2516 * expected for file systems which do not support fallocate() system call).
2517 */
2518long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
2519{
2520 handle_t *handle;
2521 ext4_fsblk_t block, max_blocks;
2522 ext4_fsblk_t nblocks = 0;
2523 int ret = 0;
2524 int ret2 = 0;
2525 int retries = 0;
2526 struct buffer_head map_bh;
2527 unsigned int credits, blkbits = inode->i_blkbits;
2528
2529 /*
2530 * currently supporting (pre)allocate mode for extent-based
2531 * files _only_
2532 */
2533 if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
2534 return -EOPNOTSUPP;
2535
2536 /* preallocation to directories is currently not supported */
2537 if (S_ISDIR(inode->i_mode))
2538 return -ENODEV;
2539
2540 block = offset >> blkbits;
2541 max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
2542 - block;
2543
2544 /*
2545 * credits to insert 1 extent into extent tree + buffers to be able to
2546 * modify 1 super block, 1 block bitmap and 1 group descriptor.
2547 */
2548 credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + 3;
2549retry:
2550 while (ret >= 0 && ret < max_blocks) {
2551 block = block + ret;
2552 max_blocks = max_blocks - ret;
2553 handle = ext4_journal_start(inode, credits);
2554 if (IS_ERR(handle)) {
2555 ret = PTR_ERR(handle);
2556 break;
2557 }
2558
2559 ret = ext4_ext_get_blocks(handle, inode, block,
2560 max_blocks, &map_bh,
2561 EXT4_CREATE_UNINITIALIZED_EXT, 0);
2562 WARN_ON(!ret);
2563 if (!ret) {
2564 ext4_error(inode->i_sb, "ext4_fallocate",
2565 "ext4_ext_get_blocks returned 0! inode#%lu"
2566 ", block=%llu, max_blocks=%llu",
2567 inode->i_ino, block, max_blocks);
2568 ret = -EIO;
2569 ext4_mark_inode_dirty(handle, inode);
2570 ret2 = ext4_journal_stop(handle);
2571 break;
2572 }
2573 if (ret > 0) {
2574 /* check wrap through sign-bit/zero here */
2575 if ((block + ret) < 0 || (block + ret) < block) {
2576 ret = -EIO;
2577 ext4_mark_inode_dirty(handle, inode);
2578 ret2 = ext4_journal_stop(handle);
2579 break;
2580 }
2581 if (buffer_new(&map_bh) && ((block + ret) >
2582 (EXT4_BLOCK_ALIGN(i_size_read(inode), blkbits)
2583 >> blkbits)))
2584 nblocks = nblocks + ret;
2585 }
2586
2587 /* Update ctime if new blocks get allocated */
2588 if (nblocks) {
2589 struct timespec now;
2590
2591 now = current_fs_time(inode->i_sb);
2592 if (!timespec_equal(&inode->i_ctime, &now))
2593 inode->i_ctime = now;
2594 }
2595
2596 ext4_mark_inode_dirty(handle, inode);
2597 ret2 = ext4_journal_stop(handle);
2598 if (ret2)
2599 break;
2600 }
2601
2602 if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
2603 goto retry;
2604
2605 /*
2606 * Time to update the file size.
2607 * Update only when preallocation was requested beyond the file size.
2608 */
2609 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
2610 (offset + len) > i_size_read(inode)) {
2611 if (ret > 0) {
2612 /*
2613 * if no error, we assume preallocation succeeded
2614 * completely
2615 */
2616 mutex_lock(&inode->i_mutex);
2617 i_size_write(inode, offset + len);
2618 EXT4_I(inode)->i_disksize = i_size_read(inode);
2619 mutex_unlock(&inode->i_mutex);
2620 } else if (ret < 0 && nblocks) {
2621 /* Handle partial allocation scenario */
2622 loff_t newsize;
2623
2624 mutex_lock(&inode->i_mutex);
2625 newsize = (nblocks << blkbits) + i_size_read(inode);
2626 i_size_write(inode, EXT4_BLOCK_ALIGN(newsize, blkbits));
2627 EXT4_I(inode)->i_disksize = i_size_read(inode);
2628 mutex_unlock(&inode->i_mutex);
2629 }
2630 }
2631
2632 return ret > 0 ? ret2 : ret;
2633}
generated by cgit v1.2.2 (git 2.25.0) at 2025-11-15 08:10:17 -0500