2 * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
3 * Written by Alex Tomas <alex@clusterfs.com>
5 * Architecture independence:
6 * Copyright (c) 2005, Bull S.A.
7 * Written by Pierre Peiffer <pierre.peiffer@bull.net>
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.
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.
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-
24 * Extents support for EXT4
27 * - ext4*_error() should be used in some situations
28 * - analyze all BUG()/BUG_ON(), use -EIO where appropriate
29 * - smart tree reduction
32 #include <linux/module.h>
34 #include <linux/time.h>
35 #include <linux/jbd2.h>
36 #include <linux/highuid.h>
37 #include <linux/pagemap.h>
38 #include <linux/quotaops.h>
39 #include <linux/string.h>
40 #include <linux/slab.h>
41 #include <linux/falloc.h>
42 #include <asm/uaccess.h>
43 #include <linux/fiemap.h>
44 #include "ext4_jbd2.h"
46 #include <trace/events/ext4.h>
49 * used by extent splitting.
51 #define EXT4_EXT_MAY_ZEROOUT 0x1 /* safe to zeroout if split fails \
53 #define EXT4_EXT_MARK_UNINIT1 0x2 /* mark first half uninitialized */
54 #define EXT4_EXT_MARK_UNINIT2 0x4 /* mark second half uninitialized */
56 #define EXT4_EXT_DATA_VALID1 0x8 /* first half contains valid data */
57 #define EXT4_EXT_DATA_VALID2 0x10 /* second half contains valid data */
59 static int ext4_split_extent(handle_t *handle,
61 struct ext4_ext_path *path,
62 struct ext4_map_blocks *map,
66 static int ext4_split_extent_at(handle_t *handle,
68 struct ext4_ext_path *path,
73 static int ext4_ext_truncate_extend_restart(handle_t *handle,
79 if (!ext4_handle_valid(handle))
81 if (handle->h_buffer_credits > needed)
83 err = ext4_journal_extend(handle, needed);
86 err = ext4_truncate_restart_trans(handle, inode, needed);
98 static int ext4_ext_get_access(handle_t *handle, struct inode *inode,
99 struct ext4_ext_path *path)
102 /* path points to block */
103 return ext4_journal_get_write_access(handle, path->p_bh);
105 /* path points to leaf/index in inode body */
106 /* we use in-core data, no need to protect them */
116 #define ext4_ext_dirty(handle, inode, path) \
117 __ext4_ext_dirty(__func__, __LINE__, (handle), (inode), (path))
118 static int __ext4_ext_dirty(const char *where, unsigned int line,
119 handle_t *handle, struct inode *inode,
120 struct ext4_ext_path *path)
124 /* path points to block */
125 err = __ext4_handle_dirty_metadata(where, line, handle,
128 /* path points to leaf/index in inode body */
129 err = ext4_mark_inode_dirty(handle, inode);
134 static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
135 struct ext4_ext_path *path,
139 int depth = path->p_depth;
140 struct ext4_extent *ex;
143 * Try to predict block placement assuming that we are
144 * filling in a file which will eventually be
145 * non-sparse --- i.e., in the case of libbfd writing
146 * an ELF object sections out-of-order but in a way
147 * the eventually results in a contiguous object or
148 * executable file, or some database extending a table
149 * space file. However, this is actually somewhat
150 * non-ideal if we are writing a sparse file such as
151 * qemu or KVM writing a raw image file that is going
152 * to stay fairly sparse, since it will end up
153 * fragmenting the file system's free space. Maybe we
154 * should have some hueristics or some way to allow
155 * userspace to pass a hint to file system,
156 * especially if the latter case turns out to be
159 ex = path[depth].p_ext;
161 ext4_fsblk_t ext_pblk = ext4_ext_pblock(ex);
162 ext4_lblk_t ext_block = le32_to_cpu(ex->ee_block);
164 if (block > ext_block)
165 return ext_pblk + (block - ext_block);
167 return ext_pblk - (ext_block - block);
170 /* it looks like index is empty;
171 * try to find starting block from index itself */
172 if (path[depth].p_bh)
173 return path[depth].p_bh->b_blocknr;
176 /* OK. use inode's group */
177 return ext4_inode_to_goal_block(inode);
181 * Allocation for a meta data block
184 ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,
185 struct ext4_ext_path *path,
186 struct ext4_extent *ex, int *err, unsigned int flags)
188 ext4_fsblk_t goal, newblock;
190 goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
191 newblock = ext4_new_meta_blocks(handle, inode, goal, flags,
196 static inline int ext4_ext_space_block(struct inode *inode, int check)
200 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
201 / sizeof(struct ext4_extent);
202 #ifdef AGGRESSIVE_TEST
203 if (!check && size > 6)
209 static inline int ext4_ext_space_block_idx(struct inode *inode, int check)
213 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
214 / sizeof(struct ext4_extent_idx);
215 #ifdef AGGRESSIVE_TEST
216 if (!check && size > 5)
222 static inline int ext4_ext_space_root(struct inode *inode, int check)
226 size = sizeof(EXT4_I(inode)->i_data);
227 size -= sizeof(struct ext4_extent_header);
228 size /= sizeof(struct ext4_extent);
229 #ifdef AGGRESSIVE_TEST
230 if (!check && size > 3)
236 static inline int ext4_ext_space_root_idx(struct inode *inode, int check)
240 size = sizeof(EXT4_I(inode)->i_data);
241 size -= sizeof(struct ext4_extent_header);
242 size /= sizeof(struct ext4_extent_idx);
243 #ifdef AGGRESSIVE_TEST
244 if (!check && size > 4)
251 * Calculate the number of metadata blocks needed
252 * to allocate @blocks
253 * Worse case is one block per extent
255 int ext4_ext_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock)
257 struct ext4_inode_info *ei = EXT4_I(inode);
260 idxs = ((inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
261 / sizeof(struct ext4_extent_idx));
264 * If the new delayed allocation block is contiguous with the
265 * previous da block, it can share index blocks with the
266 * previous block, so we only need to allocate a new index
267 * block every idxs leaf blocks. At ldxs**2 blocks, we need
268 * an additional index block, and at ldxs**3 blocks, yet
269 * another index blocks.
271 if (ei->i_da_metadata_calc_len &&
272 ei->i_da_metadata_calc_last_lblock+1 == lblock) {
275 if ((ei->i_da_metadata_calc_len % idxs) == 0)
277 if ((ei->i_da_metadata_calc_len % (idxs*idxs)) == 0)
279 if ((ei->i_da_metadata_calc_len % (idxs*idxs*idxs)) == 0) {
281 ei->i_da_metadata_calc_len = 0;
283 ei->i_da_metadata_calc_len++;
284 ei->i_da_metadata_calc_last_lblock++;
289 * In the worst case we need a new set of index blocks at
290 * every level of the inode's extent tree.
292 ei->i_da_metadata_calc_len = 1;
293 ei->i_da_metadata_calc_last_lblock = lblock;
294 return ext_depth(inode) + 1;
298 ext4_ext_max_entries(struct inode *inode, int depth)
302 if (depth == ext_depth(inode)) {
304 max = ext4_ext_space_root(inode, 1);
306 max = ext4_ext_space_root_idx(inode, 1);
309 max = ext4_ext_space_block(inode, 1);
311 max = ext4_ext_space_block_idx(inode, 1);
317 static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext)
319 ext4_fsblk_t block = ext4_ext_pblock(ext);
320 int len = ext4_ext_get_actual_len(ext);
324 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
327 static int ext4_valid_extent_idx(struct inode *inode,
328 struct ext4_extent_idx *ext_idx)
330 ext4_fsblk_t block = ext4_idx_pblock(ext_idx);
332 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, 1);
335 static int ext4_valid_extent_entries(struct inode *inode,
336 struct ext4_extent_header *eh,
339 unsigned short entries;
340 if (eh->eh_entries == 0)
343 entries = le16_to_cpu(eh->eh_entries);
347 struct ext4_extent *ext = EXT_FIRST_EXTENT(eh);
349 if (!ext4_valid_extent(inode, ext))
355 struct ext4_extent_idx *ext_idx = EXT_FIRST_INDEX(eh);
357 if (!ext4_valid_extent_idx(inode, ext_idx))
366 static int __ext4_ext_check(const char *function, unsigned int line,
367 struct inode *inode, struct ext4_extent_header *eh,
370 const char *error_msg;
373 if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
374 error_msg = "invalid magic";
377 if (unlikely(le16_to_cpu(eh->eh_depth) != depth)) {
378 error_msg = "unexpected eh_depth";
381 if (unlikely(eh->eh_max == 0)) {
382 error_msg = "invalid eh_max";
385 max = ext4_ext_max_entries(inode, depth);
386 if (unlikely(le16_to_cpu(eh->eh_max) > max)) {
387 error_msg = "too large eh_max";
390 if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
391 error_msg = "invalid eh_entries";
394 if (!ext4_valid_extent_entries(inode, eh, depth)) {
395 error_msg = "invalid extent entries";
401 ext4_error_inode(inode, function, line, 0,
402 "bad header/extent: %s - magic %x, "
403 "entries %u, max %u(%u), depth %u(%u)",
404 error_msg, le16_to_cpu(eh->eh_magic),
405 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
406 max, le16_to_cpu(eh->eh_depth), depth);
411 #define ext4_ext_check(inode, eh, depth) \
412 __ext4_ext_check(__func__, __LINE__, inode, eh, depth)
414 int ext4_ext_check_inode(struct inode *inode)
416 return ext4_ext_check(inode, ext_inode_hdr(inode), ext_depth(inode));
420 static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
422 int k, l = path->p_depth;
425 for (k = 0; k <= l; k++, path++) {
427 ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
428 ext4_idx_pblock(path->p_idx));
429 } else if (path->p_ext) {
430 ext_debug(" %d:[%d]%d:%llu ",
431 le32_to_cpu(path->p_ext->ee_block),
432 ext4_ext_is_uninitialized(path->p_ext),
433 ext4_ext_get_actual_len(path->p_ext),
434 ext4_ext_pblock(path->p_ext));
441 static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
443 int depth = ext_depth(inode);
444 struct ext4_extent_header *eh;
445 struct ext4_extent *ex;
451 eh = path[depth].p_hdr;
452 ex = EXT_FIRST_EXTENT(eh);
454 ext_debug("Displaying leaf extents for inode %lu\n", inode->i_ino);
456 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
457 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block),
458 ext4_ext_is_uninitialized(ex),
459 ext4_ext_get_actual_len(ex), ext4_ext_pblock(ex));
464 static void ext4_ext_show_move(struct inode *inode, struct ext4_ext_path *path,
465 ext4_fsblk_t newblock, int level)
467 int depth = ext_depth(inode);
468 struct ext4_extent *ex;
470 if (depth != level) {
471 struct ext4_extent_idx *idx;
472 idx = path[level].p_idx;
473 while (idx <= EXT_MAX_INDEX(path[level].p_hdr)) {
474 ext_debug("%d: move %d:%llu in new index %llu\n", level,
475 le32_to_cpu(idx->ei_block),
476 ext4_idx_pblock(idx),
484 ex = path[depth].p_ext;
485 while (ex <= EXT_MAX_EXTENT(path[depth].p_hdr)) {
486 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
487 le32_to_cpu(ex->ee_block),
489 ext4_ext_is_uninitialized(ex),
490 ext4_ext_get_actual_len(ex),
497 #define ext4_ext_show_path(inode, path)
498 #define ext4_ext_show_leaf(inode, path)
499 #define ext4_ext_show_move(inode, path, newblock, level)
502 void ext4_ext_drop_refs(struct ext4_ext_path *path)
504 int depth = path->p_depth;
507 for (i = 0; i <= depth; i++, path++)
515 * ext4_ext_binsearch_idx:
516 * binary search for the closest index of the given block
517 * the header must be checked before calling this
520 ext4_ext_binsearch_idx(struct inode *inode,
521 struct ext4_ext_path *path, ext4_lblk_t block)
523 struct ext4_extent_header *eh = path->p_hdr;
524 struct ext4_extent_idx *r, *l, *m;
527 ext_debug("binsearch for %u(idx): ", block);
529 l = EXT_FIRST_INDEX(eh) + 1;
530 r = EXT_LAST_INDEX(eh);
533 if (block < le32_to_cpu(m->ei_block))
537 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block),
538 m, le32_to_cpu(m->ei_block),
539 r, le32_to_cpu(r->ei_block));
543 ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block),
544 ext4_idx_pblock(path->p_idx));
546 #ifdef CHECK_BINSEARCH
548 struct ext4_extent_idx *chix, *ix;
551 chix = ix = EXT_FIRST_INDEX(eh);
552 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
554 le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
555 printk(KERN_DEBUG "k=%d, ix=0x%p, "
557 ix, EXT_FIRST_INDEX(eh));
558 printk(KERN_DEBUG "%u <= %u\n",
559 le32_to_cpu(ix->ei_block),
560 le32_to_cpu(ix[-1].ei_block));
562 BUG_ON(k && le32_to_cpu(ix->ei_block)
563 <= le32_to_cpu(ix[-1].ei_block));
564 if (block < le32_to_cpu(ix->ei_block))
568 BUG_ON(chix != path->p_idx);
575 * ext4_ext_binsearch:
576 * binary search for closest extent of the given block
577 * the header must be checked before calling this
580 ext4_ext_binsearch(struct inode *inode,
581 struct ext4_ext_path *path, ext4_lblk_t block)
583 struct ext4_extent_header *eh = path->p_hdr;
584 struct ext4_extent *r, *l, *m;
586 if (eh->eh_entries == 0) {
588 * this leaf is empty:
589 * we get such a leaf in split/add case
594 ext_debug("binsearch for %u: ", block);
596 l = EXT_FIRST_EXTENT(eh) + 1;
597 r = EXT_LAST_EXTENT(eh);
601 if (block < le32_to_cpu(m->ee_block))
605 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block),
606 m, le32_to_cpu(m->ee_block),
607 r, le32_to_cpu(r->ee_block));
611 ext_debug(" -> %d:%llu:[%d]%d ",
612 le32_to_cpu(path->p_ext->ee_block),
613 ext4_ext_pblock(path->p_ext),
614 ext4_ext_is_uninitialized(path->p_ext),
615 ext4_ext_get_actual_len(path->p_ext));
617 #ifdef CHECK_BINSEARCH
619 struct ext4_extent *chex, *ex;
622 chex = ex = EXT_FIRST_EXTENT(eh);
623 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
624 BUG_ON(k && le32_to_cpu(ex->ee_block)
625 <= le32_to_cpu(ex[-1].ee_block));
626 if (block < le32_to_cpu(ex->ee_block))
630 BUG_ON(chex != path->p_ext);
636 int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
638 struct ext4_extent_header *eh;
640 eh = ext_inode_hdr(inode);
643 eh->eh_magic = EXT4_EXT_MAGIC;
644 eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode, 0));
645 ext4_mark_inode_dirty(handle, inode);
646 ext4_ext_invalidate_cache(inode);
650 struct ext4_ext_path *
651 ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
652 struct ext4_ext_path *path)
654 struct ext4_extent_header *eh;
655 struct buffer_head *bh;
656 short int depth, i, ppos = 0, alloc = 0;
659 eh = ext_inode_hdr(inode);
660 depth = ext_depth(inode);
662 /* account possible depth increase */
664 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 2),
667 return ERR_PTR(-ENOMEM);
674 /* walk through the tree */
676 int need_to_validate = 0;
678 ext_debug("depth %d: num %d, max %d\n",
679 ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
681 ext4_ext_binsearch_idx(inode, path + ppos, block);
682 path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx);
683 path[ppos].p_depth = i;
684 path[ppos].p_ext = NULL;
686 bh = sb_getblk(inode->i_sb, path[ppos].p_block);
691 if (!bh_uptodate_or_lock(bh)) {
692 trace_ext4_ext_load_extent(inode, block,
694 ret = bh_submit_read(bh);
699 /* validate the extent entries */
700 need_to_validate = 1;
702 eh = ext_block_hdr(bh);
704 if (unlikely(ppos > depth)) {
706 EXT4_ERROR_INODE(inode,
707 "ppos %d > depth %d", ppos, depth);
711 path[ppos].p_bh = bh;
712 path[ppos].p_hdr = eh;
715 ret = need_to_validate ? ext4_ext_check(inode, eh, i) : 0;
720 path[ppos].p_depth = i;
721 path[ppos].p_ext = NULL;
722 path[ppos].p_idx = NULL;
725 ext4_ext_binsearch(inode, path + ppos, block);
726 /* if not an empty leaf */
727 if (path[ppos].p_ext)
728 path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext);
730 ext4_ext_show_path(inode, path);
735 ext4_ext_drop_refs(path);
742 * ext4_ext_insert_index:
743 * insert new index [@logical;@ptr] into the block at @curp;
744 * check where to insert: before @curp or after @curp
746 static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
747 struct ext4_ext_path *curp,
748 int logical, ext4_fsblk_t ptr)
750 struct ext4_extent_idx *ix;
753 err = ext4_ext_get_access(handle, inode, curp);
757 if (unlikely(logical == le32_to_cpu(curp->p_idx->ei_block))) {
758 EXT4_ERROR_INODE(inode,
759 "logical %d == ei_block %d!",
760 logical, le32_to_cpu(curp->p_idx->ei_block));
764 if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries)
765 >= le16_to_cpu(curp->p_hdr->eh_max))) {
766 EXT4_ERROR_INODE(inode,
767 "eh_entries %d >= eh_max %d!",
768 le16_to_cpu(curp->p_hdr->eh_entries),
769 le16_to_cpu(curp->p_hdr->eh_max));
773 if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
775 ext_debug("insert new index %d after: %llu\n", logical, ptr);
776 ix = curp->p_idx + 1;
779 ext_debug("insert new index %d before: %llu\n", logical, ptr);
783 len = EXT_LAST_INDEX(curp->p_hdr) - ix + 1;
786 ext_debug("insert new index %d: "
787 "move %d indices from 0x%p to 0x%p\n",
788 logical, len, ix, ix + 1);
789 memmove(ix + 1, ix, len * sizeof(struct ext4_extent_idx));
792 if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) {
793 EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!");
797 ix->ei_block = cpu_to_le32(logical);
798 ext4_idx_store_pblock(ix, ptr);
799 le16_add_cpu(&curp->p_hdr->eh_entries, 1);
801 if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) {
802 EXT4_ERROR_INODE(inode, "ix > EXT_LAST_INDEX!");
806 err = ext4_ext_dirty(handle, inode, curp);
807 ext4_std_error(inode->i_sb, err);
814 * inserts new subtree into the path, using free index entry
816 * - allocates all needed blocks (new leaf and all intermediate index blocks)
817 * - makes decision where to split
818 * - moves remaining extents and index entries (right to the split point)
819 * into the newly allocated blocks
820 * - initializes subtree
822 static int ext4_ext_split(handle_t *handle, struct inode *inode,
824 struct ext4_ext_path *path,
825 struct ext4_extent *newext, int at)
827 struct buffer_head *bh = NULL;
828 int depth = ext_depth(inode);
829 struct ext4_extent_header *neh;
830 struct ext4_extent_idx *fidx;
832 ext4_fsblk_t newblock, oldblock;
834 ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */
837 /* make decision: where to split? */
838 /* FIXME: now decision is simplest: at current extent */
840 /* if current leaf will be split, then we should use
841 * border from split point */
842 if (unlikely(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr))) {
843 EXT4_ERROR_INODE(inode, "p_ext > EXT_MAX_EXTENT!");
846 if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
847 border = path[depth].p_ext[1].ee_block;
848 ext_debug("leaf will be split."
849 " next leaf starts at %d\n",
850 le32_to_cpu(border));
852 border = newext->ee_block;
853 ext_debug("leaf will be added."
854 " next leaf starts at %d\n",
855 le32_to_cpu(border));
859 * If error occurs, then we break processing
860 * and mark filesystem read-only. index won't
861 * be inserted and tree will be in consistent
862 * state. Next mount will repair buffers too.
866 * Get array to track all allocated blocks.
867 * We need this to handle errors and free blocks
870 ablocks = kzalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS);
874 /* allocate all needed blocks */
875 ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
876 for (a = 0; a < depth - at; a++) {
877 newblock = ext4_ext_new_meta_block(handle, inode, path,
878 newext, &err, flags);
881 ablocks[a] = newblock;
884 /* initialize new leaf */
885 newblock = ablocks[--a];
886 if (unlikely(newblock == 0)) {
887 EXT4_ERROR_INODE(inode, "newblock == 0!");
891 bh = sb_getblk(inode->i_sb, newblock);
898 err = ext4_journal_get_create_access(handle, bh);
902 neh = ext_block_hdr(bh);
904 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
905 neh->eh_magic = EXT4_EXT_MAGIC;
908 /* move remainder of path[depth] to the new leaf */
909 if (unlikely(path[depth].p_hdr->eh_entries !=
910 path[depth].p_hdr->eh_max)) {
911 EXT4_ERROR_INODE(inode, "eh_entries %d != eh_max %d!",
912 path[depth].p_hdr->eh_entries,
913 path[depth].p_hdr->eh_max);
917 /* start copy from next extent */
918 m = EXT_MAX_EXTENT(path[depth].p_hdr) - path[depth].p_ext++;
919 ext4_ext_show_move(inode, path, newblock, depth);
921 struct ext4_extent *ex;
922 ex = EXT_FIRST_EXTENT(neh);
923 memmove(ex, path[depth].p_ext, sizeof(struct ext4_extent) * m);
924 le16_add_cpu(&neh->eh_entries, m);
927 set_buffer_uptodate(bh);
930 err = ext4_handle_dirty_metadata(handle, inode, bh);
936 /* correct old leaf */
938 err = ext4_ext_get_access(handle, inode, path + depth);
941 le16_add_cpu(&path[depth].p_hdr->eh_entries, -m);
942 err = ext4_ext_dirty(handle, inode, path + depth);
948 /* create intermediate indexes */
950 if (unlikely(k < 0)) {
951 EXT4_ERROR_INODE(inode, "k %d < 0!", k);
956 ext_debug("create %d intermediate indices\n", k);
957 /* insert new index into current index block */
958 /* current depth stored in i var */
962 newblock = ablocks[--a];
963 bh = sb_getblk(inode->i_sb, newblock);
970 err = ext4_journal_get_create_access(handle, bh);
974 neh = ext_block_hdr(bh);
975 neh->eh_entries = cpu_to_le16(1);
976 neh->eh_magic = EXT4_EXT_MAGIC;
977 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
978 neh->eh_depth = cpu_to_le16(depth - i);
979 fidx = EXT_FIRST_INDEX(neh);
980 fidx->ei_block = border;
981 ext4_idx_store_pblock(fidx, oldblock);
983 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
984 i, newblock, le32_to_cpu(border), oldblock);
986 /* move remainder of path[i] to the new index block */
987 if (unlikely(EXT_MAX_INDEX(path[i].p_hdr) !=
988 EXT_LAST_INDEX(path[i].p_hdr))) {
989 EXT4_ERROR_INODE(inode,
990 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
991 le32_to_cpu(path[i].p_ext->ee_block));
995 /* start copy indexes */
996 m = EXT_MAX_INDEX(path[i].p_hdr) - path[i].p_idx++;
997 ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
998 EXT_MAX_INDEX(path[i].p_hdr));
999 ext4_ext_show_move(inode, path, newblock, i);
1001 memmove(++fidx, path[i].p_idx,
1002 sizeof(struct ext4_extent_idx) * m);
1003 le16_add_cpu(&neh->eh_entries, m);
1005 set_buffer_uptodate(bh);
1008 err = ext4_handle_dirty_metadata(handle, inode, bh);
1014 /* correct old index */
1016 err = ext4_ext_get_access(handle, inode, path + i);
1019 le16_add_cpu(&path[i].p_hdr->eh_entries, -m);
1020 err = ext4_ext_dirty(handle, inode, path + i);
1028 /* insert new index */
1029 err = ext4_ext_insert_index(handle, inode, path + at,
1030 le32_to_cpu(border), newblock);
1034 if (buffer_locked(bh))
1040 /* free all allocated blocks in error case */
1041 for (i = 0; i < depth; i++) {
1044 ext4_free_blocks(handle, inode, NULL, ablocks[i], 1,
1045 EXT4_FREE_BLOCKS_METADATA);
1054 * ext4_ext_grow_indepth:
1055 * implements tree growing procedure:
1056 * - allocates new block
1057 * - moves top-level data (index block or leaf) into the new block
1058 * - initializes new top-level, creating index that points to the
1059 * just created block
1061 static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
1063 struct ext4_extent *newext)
1065 struct ext4_extent_header *neh;
1066 struct buffer_head *bh;
1067 ext4_fsblk_t newblock;
1070 newblock = ext4_ext_new_meta_block(handle, inode, NULL,
1071 newext, &err, flags);
1075 bh = sb_getblk(inode->i_sb, newblock);
1080 err = ext4_journal_get_create_access(handle, bh);
1086 /* move top-level index/leaf into new block */
1087 memmove(bh->b_data, EXT4_I(inode)->i_data,
1088 sizeof(EXT4_I(inode)->i_data));
1090 /* set size of new block */
1091 neh = ext_block_hdr(bh);
1092 /* old root could have indexes or leaves
1093 * so calculate e_max right way */
1094 if (ext_depth(inode))
1095 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
1097 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
1098 neh->eh_magic = EXT4_EXT_MAGIC;
1099 set_buffer_uptodate(bh);
1102 err = ext4_handle_dirty_metadata(handle, inode, bh);
1106 /* Update top-level index: num,max,pointer */
1107 neh = ext_inode_hdr(inode);
1108 neh->eh_entries = cpu_to_le16(1);
1109 ext4_idx_store_pblock(EXT_FIRST_INDEX(neh), newblock);
1110 if (neh->eh_depth == 0) {
1111 /* Root extent block becomes index block */
1112 neh->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode, 0));
1113 EXT_FIRST_INDEX(neh)->ei_block =
1114 EXT_FIRST_EXTENT(neh)->ee_block;
1116 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1117 le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
1118 le32_to_cpu(EXT_FIRST_INDEX(neh)->ei_block),
1119 ext4_idx_pblock(EXT_FIRST_INDEX(neh)));
1121 neh->eh_depth = cpu_to_le16(le16_to_cpu(neh->eh_depth) + 1);
1122 ext4_mark_inode_dirty(handle, inode);
1130 * ext4_ext_create_new_leaf:
1131 * finds empty index and adds new leaf.
1132 * if no free index is found, then it requests in-depth growing.
1134 static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
1136 struct ext4_ext_path *path,
1137 struct ext4_extent *newext)
1139 struct ext4_ext_path *curp;
1140 int depth, i, err = 0;
1143 i = depth = ext_depth(inode);
1145 /* walk up to the tree and look for free index entry */
1146 curp = path + depth;
1147 while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
1152 /* we use already allocated block for index block,
1153 * so subsequent data blocks should be contiguous */
1154 if (EXT_HAS_FREE_INDEX(curp)) {
1155 /* if we found index with free entry, then use that
1156 * entry: create all needed subtree and add new leaf */
1157 err = ext4_ext_split(handle, inode, flags, path, newext, i);
1162 ext4_ext_drop_refs(path);
1163 path = ext4_ext_find_extent(inode,
1164 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1167 err = PTR_ERR(path);
1169 /* tree is full, time to grow in depth */
1170 err = ext4_ext_grow_indepth(handle, inode, flags, newext);
1175 ext4_ext_drop_refs(path);
1176 path = ext4_ext_find_extent(inode,
1177 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1180 err = PTR_ERR(path);
1185 * only first (depth 0 -> 1) produces free space;
1186 * in all other cases we have to split the grown tree
1188 depth = ext_depth(inode);
1189 if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
1190 /* now we need to split */
1200 * search the closest allocated block to the left for *logical
1201 * and returns it at @logical + it's physical address at @phys
1202 * if *logical is the smallest allocated block, the function
1203 * returns 0 at @phys
1204 * return value contains 0 (success) or error code
1206 static int ext4_ext_search_left(struct inode *inode,
1207 struct ext4_ext_path *path,
1208 ext4_lblk_t *logical, ext4_fsblk_t *phys)
1210 struct ext4_extent_idx *ix;
1211 struct ext4_extent *ex;
1214 if (unlikely(path == NULL)) {
1215 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1218 depth = path->p_depth;
1221 if (depth == 0 && path->p_ext == NULL)
1224 /* usually extent in the path covers blocks smaller
1225 * then *logical, but it can be that extent is the
1226 * first one in the file */
1228 ex = path[depth].p_ext;
1229 ee_len = ext4_ext_get_actual_len(ex);
1230 if (*logical < le32_to_cpu(ex->ee_block)) {
1231 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1232 EXT4_ERROR_INODE(inode,
1233 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
1234 *logical, le32_to_cpu(ex->ee_block));
1237 while (--depth >= 0) {
1238 ix = path[depth].p_idx;
1239 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1240 EXT4_ERROR_INODE(inode,
1241 "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
1242 ix != NULL ? le32_to_cpu(ix->ei_block) : 0,
1243 EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ?
1244 le32_to_cpu(EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block) : 0,
1252 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1253 EXT4_ERROR_INODE(inode,
1254 "logical %d < ee_block %d + ee_len %d!",
1255 *logical, le32_to_cpu(ex->ee_block), ee_len);
1259 *logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
1260 *phys = ext4_ext_pblock(ex) + ee_len - 1;
1265 * search the closest allocated block to the right for *logical
1266 * and returns it at @logical + it's physical address at @phys
1267 * if *logical is the largest allocated block, the function
1268 * returns 0 at @phys
1269 * return value contains 0 (success) or error code
1271 static int ext4_ext_search_right(struct inode *inode,
1272 struct ext4_ext_path *path,
1273 ext4_lblk_t *logical, ext4_fsblk_t *phys,
1274 struct ext4_extent **ret_ex)
1276 struct buffer_head *bh = NULL;
1277 struct ext4_extent_header *eh;
1278 struct ext4_extent_idx *ix;
1279 struct ext4_extent *ex;
1281 int depth; /* Note, NOT eh_depth; depth from top of tree */
1284 if (unlikely(path == NULL)) {
1285 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1288 depth = path->p_depth;
1291 if (depth == 0 && path->p_ext == NULL)
1294 /* usually extent in the path covers blocks smaller
1295 * then *logical, but it can be that extent is the
1296 * first one in the file */
1298 ex = path[depth].p_ext;
1299 ee_len = ext4_ext_get_actual_len(ex);
1300 if (*logical < le32_to_cpu(ex->ee_block)) {
1301 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1302 EXT4_ERROR_INODE(inode,
1303 "first_extent(path[%d].p_hdr) != ex",
1307 while (--depth >= 0) {
1308 ix = path[depth].p_idx;
1309 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1310 EXT4_ERROR_INODE(inode,
1311 "ix != EXT_FIRST_INDEX *logical %d!",
1319 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1320 EXT4_ERROR_INODE(inode,
1321 "logical %d < ee_block %d + ee_len %d!",
1322 *logical, le32_to_cpu(ex->ee_block), ee_len);
1326 if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
1327 /* next allocated block in this leaf */
1332 /* go up and search for index to the right */
1333 while (--depth >= 0) {
1334 ix = path[depth].p_idx;
1335 if (ix != EXT_LAST_INDEX(path[depth].p_hdr))
1339 /* we've gone up to the root and found no index to the right */
1343 /* we've found index to the right, let's
1344 * follow it and find the closest allocated
1345 * block to the right */
1347 block = ext4_idx_pblock(ix);
1348 while (++depth < path->p_depth) {
1349 bh = sb_bread(inode->i_sb, block);
1352 eh = ext_block_hdr(bh);
1353 /* subtract from p_depth to get proper eh_depth */
1354 if (ext4_ext_check(inode, eh, path->p_depth - depth)) {
1358 ix = EXT_FIRST_INDEX(eh);
1359 block = ext4_idx_pblock(ix);
1363 bh = sb_bread(inode->i_sb, block);
1366 eh = ext_block_hdr(bh);
1367 if (ext4_ext_check(inode, eh, path->p_depth - depth)) {
1371 ex = EXT_FIRST_EXTENT(eh);
1373 *logical = le32_to_cpu(ex->ee_block);
1374 *phys = ext4_ext_pblock(ex);
1382 * ext4_ext_next_allocated_block:
1383 * returns allocated block in subsequent extent or EXT_MAX_BLOCKS.
1384 * NOTE: it considers block number from index entry as
1385 * allocated block. Thus, index entries have to be consistent
1389 ext4_ext_next_allocated_block(struct ext4_ext_path *path)
1393 BUG_ON(path == NULL);
1394 depth = path->p_depth;
1396 if (depth == 0 && path->p_ext == NULL)
1397 return EXT_MAX_BLOCKS;
1399 while (depth >= 0) {
1400 if (depth == path->p_depth) {
1402 if (path[depth].p_ext &&
1403 path[depth].p_ext !=
1404 EXT_LAST_EXTENT(path[depth].p_hdr))
1405 return le32_to_cpu(path[depth].p_ext[1].ee_block);
1408 if (path[depth].p_idx !=
1409 EXT_LAST_INDEX(path[depth].p_hdr))
1410 return le32_to_cpu(path[depth].p_idx[1].ei_block);
1415 return EXT_MAX_BLOCKS;
1419 * ext4_ext_next_leaf_block:
1420 * returns first allocated block from next leaf or EXT_MAX_BLOCKS
1422 static ext4_lblk_t ext4_ext_next_leaf_block(struct ext4_ext_path *path)
1426 BUG_ON(path == NULL);
1427 depth = path->p_depth;
1429 /* zero-tree has no leaf blocks at all */
1431 return EXT_MAX_BLOCKS;
1433 /* go to index block */
1436 while (depth >= 0) {
1437 if (path[depth].p_idx !=
1438 EXT_LAST_INDEX(path[depth].p_hdr))
1439 return (ext4_lblk_t)
1440 le32_to_cpu(path[depth].p_idx[1].ei_block);
1444 return EXT_MAX_BLOCKS;
1448 * ext4_ext_correct_indexes:
1449 * if leaf gets modified and modified extent is first in the leaf,
1450 * then we have to correct all indexes above.
1451 * TODO: do we need to correct tree in all cases?
1453 static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
1454 struct ext4_ext_path *path)
1456 struct ext4_extent_header *eh;
1457 int depth = ext_depth(inode);
1458 struct ext4_extent *ex;
1462 eh = path[depth].p_hdr;
1463 ex = path[depth].p_ext;
1465 if (unlikely(ex == NULL || eh == NULL)) {
1466 EXT4_ERROR_INODE(inode,
1467 "ex %p == NULL or eh %p == NULL", ex, eh);
1472 /* there is no tree at all */
1476 if (ex != EXT_FIRST_EXTENT(eh)) {
1477 /* we correct tree if first leaf got modified only */
1482 * TODO: we need correction if border is smaller than current one
1485 border = path[depth].p_ext->ee_block;
1486 err = ext4_ext_get_access(handle, inode, path + k);
1489 path[k].p_idx->ei_block = border;
1490 err = ext4_ext_dirty(handle, inode, path + k);
1495 /* change all left-side indexes */
1496 if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
1498 err = ext4_ext_get_access(handle, inode, path + k);
1501 path[k].p_idx->ei_block = border;
1502 err = ext4_ext_dirty(handle, inode, path + k);
1511 ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
1512 struct ext4_extent *ex2)
1514 unsigned short ext1_ee_len, ext2_ee_len, max_len;
1517 * Make sure that either both extents are uninitialized, or
1520 if (ext4_ext_is_uninitialized(ex1) ^ ext4_ext_is_uninitialized(ex2))
1523 if (ext4_ext_is_uninitialized(ex1))
1524 max_len = EXT_UNINIT_MAX_LEN;
1526 max_len = EXT_INIT_MAX_LEN;
1528 ext1_ee_len = ext4_ext_get_actual_len(ex1);
1529 ext2_ee_len = ext4_ext_get_actual_len(ex2);
1531 if (le32_to_cpu(ex1->ee_block) + ext1_ee_len !=
1532 le32_to_cpu(ex2->ee_block))
1536 * To allow future support for preallocated extents to be added
1537 * as an RO_COMPAT feature, refuse to merge to extents if
1538 * this can result in the top bit of ee_len being set.
1540 if (ext1_ee_len + ext2_ee_len > max_len)
1542 #ifdef AGGRESSIVE_TEST
1543 if (ext1_ee_len >= 4)
1547 if (ext4_ext_pblock(ex1) + ext1_ee_len == ext4_ext_pblock(ex2))
1553 * This function tries to merge the "ex" extent to the next extent in the tree.
1554 * It always tries to merge towards right. If you want to merge towards
1555 * left, pass "ex - 1" as argument instead of "ex".
1556 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1557 * 1 if they got merged.
1559 static int ext4_ext_try_to_merge_right(struct inode *inode,
1560 struct ext4_ext_path *path,
1561 struct ext4_extent *ex)
1563 struct ext4_extent_header *eh;
1564 unsigned int depth, len;
1566 int uninitialized = 0;
1568 depth = ext_depth(inode);
1569 BUG_ON(path[depth].p_hdr == NULL);
1570 eh = path[depth].p_hdr;
1572 while (ex < EXT_LAST_EXTENT(eh)) {
1573 if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
1575 /* merge with next extent! */
1576 if (ext4_ext_is_uninitialized(ex))
1578 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1579 + ext4_ext_get_actual_len(ex + 1));
1581 ext4_ext_mark_uninitialized(ex);
1583 if (ex + 1 < EXT_LAST_EXTENT(eh)) {
1584 len = (EXT_LAST_EXTENT(eh) - ex - 1)
1585 * sizeof(struct ext4_extent);
1586 memmove(ex + 1, ex + 2, len);
1588 le16_add_cpu(&eh->eh_entries, -1);
1590 WARN_ON(eh->eh_entries == 0);
1591 if (!eh->eh_entries)
1592 EXT4_ERROR_INODE(inode, "eh->eh_entries = 0!");
1599 * This function tries to merge the @ex extent to neighbours in the tree.
1600 * return 1 if merge left else 0.
1602 static int ext4_ext_try_to_merge(struct inode *inode,
1603 struct ext4_ext_path *path,
1604 struct ext4_extent *ex) {
1605 struct ext4_extent_header *eh;
1610 depth = ext_depth(inode);
1611 BUG_ON(path[depth].p_hdr == NULL);
1612 eh = path[depth].p_hdr;
1614 if (ex > EXT_FIRST_EXTENT(eh))
1615 merge_done = ext4_ext_try_to_merge_right(inode, path, ex - 1);
1618 ret = ext4_ext_try_to_merge_right(inode, path, ex);
1624 * check if a portion of the "newext" extent overlaps with an
1627 * If there is an overlap discovered, it updates the length of the newext
1628 * such that there will be no overlap, and then returns 1.
1629 * If there is no overlap found, it returns 0.
1631 static unsigned int ext4_ext_check_overlap(struct ext4_sb_info *sbi,
1632 struct inode *inode,
1633 struct ext4_extent *newext,
1634 struct ext4_ext_path *path)
1637 unsigned int depth, len1;
1638 unsigned int ret = 0;
1640 b1 = le32_to_cpu(newext->ee_block);
1641 len1 = ext4_ext_get_actual_len(newext);
1642 depth = ext_depth(inode);
1643 if (!path[depth].p_ext)
1645 b2 = le32_to_cpu(path[depth].p_ext->ee_block);
1646 b2 &= ~(sbi->s_cluster_ratio - 1);
1649 * get the next allocated block if the extent in the path
1650 * is before the requested block(s)
1653 b2 = ext4_ext_next_allocated_block(path);
1654 if (b2 == EXT_MAX_BLOCKS)
1656 b2 &= ~(sbi->s_cluster_ratio - 1);
1659 /* check for wrap through zero on extent logical start block*/
1660 if (b1 + len1 < b1) {
1661 len1 = EXT_MAX_BLOCKS - b1;
1662 newext->ee_len = cpu_to_le16(len1);
1666 /* check for overlap */
1667 if (b1 + len1 > b2) {
1668 newext->ee_len = cpu_to_le16(b2 - b1);
1676 * ext4_ext_insert_extent:
1677 * tries to merge requsted extent into the existing extent or
1678 * inserts requested extent as new one into the tree,
1679 * creating new leaf in the no-space case.
1681 int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
1682 struct ext4_ext_path *path,
1683 struct ext4_extent *newext, int flag)
1685 struct ext4_extent_header *eh;
1686 struct ext4_extent *ex, *fex;
1687 struct ext4_extent *nearex; /* nearest extent */
1688 struct ext4_ext_path *npath = NULL;
1689 int depth, len, err;
1691 unsigned uninitialized = 0;
1694 if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
1695 EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
1698 depth = ext_depth(inode);
1699 ex = path[depth].p_ext;
1700 if (unlikely(path[depth].p_hdr == NULL)) {
1701 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
1705 /* try to insert block into found extent and return */
1706 if (ex && !(flag & EXT4_GET_BLOCKS_PRE_IO)
1707 && ext4_can_extents_be_merged(inode, ex, newext)) {
1708 ext_debug("append [%d]%d block to %u:[%d]%d (from %llu)\n",
1709 ext4_ext_is_uninitialized(newext),
1710 ext4_ext_get_actual_len(newext),
1711 le32_to_cpu(ex->ee_block),
1712 ext4_ext_is_uninitialized(ex),
1713 ext4_ext_get_actual_len(ex),
1714 ext4_ext_pblock(ex));
1715 err = ext4_ext_get_access(handle, inode, path + depth);
1720 * ext4_can_extents_be_merged should have checked that either
1721 * both extents are uninitialized, or both aren't. Thus we
1722 * need to check only one of them here.
1724 if (ext4_ext_is_uninitialized(ex))
1726 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1727 + ext4_ext_get_actual_len(newext));
1729 ext4_ext_mark_uninitialized(ex);
1730 eh = path[depth].p_hdr;
1735 depth = ext_depth(inode);
1736 eh = path[depth].p_hdr;
1737 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
1740 /* probably next leaf has space for us? */
1741 fex = EXT_LAST_EXTENT(eh);
1742 next = EXT_MAX_BLOCKS;
1743 if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block))
1744 next = ext4_ext_next_leaf_block(path);
1745 if (next != EXT_MAX_BLOCKS) {
1746 ext_debug("next leaf block - %u\n", next);
1747 BUG_ON(npath != NULL);
1748 npath = ext4_ext_find_extent(inode, next, NULL);
1750 return PTR_ERR(npath);
1751 BUG_ON(npath->p_depth != path->p_depth);
1752 eh = npath[depth].p_hdr;
1753 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
1754 ext_debug("next leaf isn't full(%d)\n",
1755 le16_to_cpu(eh->eh_entries));
1759 ext_debug("next leaf has no free space(%d,%d)\n",
1760 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
1764 * There is no free space in the found leaf.
1765 * We're gonna add a new leaf in the tree.
1767 if (flag & EXT4_GET_BLOCKS_PUNCH_OUT_EXT)
1768 flags = EXT4_MB_USE_ROOT_BLOCKS;
1769 err = ext4_ext_create_new_leaf(handle, inode, flags, path, newext);
1772 depth = ext_depth(inode);
1773 eh = path[depth].p_hdr;
1776 nearex = path[depth].p_ext;
1778 err = ext4_ext_get_access(handle, inode, path + depth);
1783 /* there is no extent in this leaf, create first one */
1784 ext_debug("first extent in the leaf: %u:%llu:[%d]%d\n",
1785 le32_to_cpu(newext->ee_block),
1786 ext4_ext_pblock(newext),
1787 ext4_ext_is_uninitialized(newext),
1788 ext4_ext_get_actual_len(newext));
1789 nearex = EXT_FIRST_EXTENT(eh);
1791 if (le32_to_cpu(newext->ee_block)
1792 > le32_to_cpu(nearex->ee_block)) {
1794 ext_debug("insert %u:%llu:[%d]%d before: "
1796 le32_to_cpu(newext->ee_block),
1797 ext4_ext_pblock(newext),
1798 ext4_ext_is_uninitialized(newext),
1799 ext4_ext_get_actual_len(newext),
1804 BUG_ON(newext->ee_block == nearex->ee_block);
1805 ext_debug("insert %u:%llu:[%d]%d after: "
1807 le32_to_cpu(newext->ee_block),
1808 ext4_ext_pblock(newext),
1809 ext4_ext_is_uninitialized(newext),
1810 ext4_ext_get_actual_len(newext),
1813 len = EXT_LAST_EXTENT(eh) - nearex + 1;
1815 ext_debug("insert %u:%llu:[%d]%d: "
1816 "move %d extents from 0x%p to 0x%p\n",
1817 le32_to_cpu(newext->ee_block),
1818 ext4_ext_pblock(newext),
1819 ext4_ext_is_uninitialized(newext),
1820 ext4_ext_get_actual_len(newext),
1821 len, nearex, nearex + 1);
1822 memmove(nearex + 1, nearex,
1823 len * sizeof(struct ext4_extent));
1827 le16_add_cpu(&eh->eh_entries, 1);
1828 path[depth].p_ext = nearex;
1829 nearex->ee_block = newext->ee_block;
1830 ext4_ext_store_pblock(nearex, ext4_ext_pblock(newext));
1831 nearex->ee_len = newext->ee_len;
1834 /* try to merge extents to the right */
1835 if (!(flag & EXT4_GET_BLOCKS_PRE_IO))
1836 ext4_ext_try_to_merge(inode, path, nearex);
1838 /* try to merge extents to the left */
1840 /* time to correct all indexes above */
1841 err = ext4_ext_correct_indexes(handle, inode, path);
1845 err = ext4_ext_dirty(handle, inode, path + depth);
1849 ext4_ext_drop_refs(npath);
1852 ext4_ext_invalidate_cache(inode);
1856 static int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
1857 ext4_lblk_t num, ext_prepare_callback func,
1860 struct ext4_ext_path *path = NULL;
1861 struct ext4_ext_cache cbex;
1862 struct ext4_extent *ex;
1863 ext4_lblk_t next, start = 0, end = 0;
1864 ext4_lblk_t last = block + num;
1865 int depth, exists, err = 0;
1867 BUG_ON(func == NULL);
1868 BUG_ON(inode == NULL);
1870 while (block < last && block != EXT_MAX_BLOCKS) {
1872 /* find extent for this block */
1873 down_read(&EXT4_I(inode)->i_data_sem);
1874 path = ext4_ext_find_extent(inode, block, path);
1875 up_read(&EXT4_I(inode)->i_data_sem);
1877 err = PTR_ERR(path);
1882 depth = ext_depth(inode);
1883 if (unlikely(path[depth].p_hdr == NULL)) {
1884 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
1888 ex = path[depth].p_ext;
1889 next = ext4_ext_next_allocated_block(path);
1893 /* there is no extent yet, so try to allocate
1894 * all requested space */
1897 } else if (le32_to_cpu(ex->ee_block) > block) {
1898 /* need to allocate space before found extent */
1900 end = le32_to_cpu(ex->ee_block);
1901 if (block + num < end)
1903 } else if (block >= le32_to_cpu(ex->ee_block)
1904 + ext4_ext_get_actual_len(ex)) {
1905 /* need to allocate space after found extent */
1910 } else if (block >= le32_to_cpu(ex->ee_block)) {
1912 * some part of requested space is covered
1916 end = le32_to_cpu(ex->ee_block)
1917 + ext4_ext_get_actual_len(ex);
1918 if (block + num < end)
1924 BUG_ON(end <= start);
1927 cbex.ec_block = start;
1928 cbex.ec_len = end - start;
1931 cbex.ec_block = le32_to_cpu(ex->ee_block);
1932 cbex.ec_len = ext4_ext_get_actual_len(ex);
1933 cbex.ec_start = ext4_ext_pblock(ex);
1936 if (unlikely(cbex.ec_len == 0)) {
1937 EXT4_ERROR_INODE(inode, "cbex.ec_len == 0");
1941 err = func(inode, next, &cbex, ex, cbdata);
1942 ext4_ext_drop_refs(path);
1947 if (err == EXT_REPEAT)
1949 else if (err == EXT_BREAK) {
1954 if (ext_depth(inode) != depth) {
1955 /* depth was changed. we have to realloc path */
1960 block = cbex.ec_block + cbex.ec_len;
1964 ext4_ext_drop_refs(path);
1972 ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block,
1973 __u32 len, ext4_fsblk_t start)
1975 struct ext4_ext_cache *cex;
1977 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
1978 trace_ext4_ext_put_in_cache(inode, block, len, start);
1979 cex = &EXT4_I(inode)->i_cached_extent;
1980 cex->ec_block = block;
1982 cex->ec_start = start;
1983 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
1987 * ext4_ext_put_gap_in_cache:
1988 * calculate boundaries of the gap that the requested block fits into
1989 * and cache this gap
1992 ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
1995 int depth = ext_depth(inode);
1998 struct ext4_extent *ex;
2000 ex = path[depth].p_ext;
2002 /* there is no extent yet, so gap is [0;-] */
2004 len = EXT_MAX_BLOCKS;
2005 ext_debug("cache gap(whole file):");
2006 } else if (block < le32_to_cpu(ex->ee_block)) {
2008 len = le32_to_cpu(ex->ee_block) - block;
2009 ext_debug("cache gap(before): %u [%u:%u]",
2011 le32_to_cpu(ex->ee_block),
2012 ext4_ext_get_actual_len(ex));
2013 } else if (block >= le32_to_cpu(ex->ee_block)
2014 + ext4_ext_get_actual_len(ex)) {
2016 lblock = le32_to_cpu(ex->ee_block)
2017 + ext4_ext_get_actual_len(ex);
2019 next = ext4_ext_next_allocated_block(path);
2020 ext_debug("cache gap(after): [%u:%u] %u",
2021 le32_to_cpu(ex->ee_block),
2022 ext4_ext_get_actual_len(ex),
2024 BUG_ON(next == lblock);
2025 len = next - lblock;
2031 ext_debug(" -> %u:%lu\n", lblock, len);
2032 ext4_ext_put_in_cache(inode, lblock, len, 0);
2036 * ext4_ext_check_cache()
2037 * Checks to see if the given block is in the cache.
2038 * If it is, the cached extent is stored in the given
2039 * cache extent pointer. If the cached extent is a hole,
2040 * this routine should be used instead of
2041 * ext4_ext_in_cache if the calling function needs to
2042 * know the size of the hole.
2044 * @inode: The files inode
2045 * @block: The block to look for in the cache
2046 * @ex: Pointer where the cached extent will be stored
2047 * if it contains block
2049 * Return 0 if cache is invalid; 1 if the cache is valid
2051 static int ext4_ext_check_cache(struct inode *inode, ext4_lblk_t block,
2052 struct ext4_ext_cache *ex){
2053 struct ext4_ext_cache *cex;
2054 struct ext4_sb_info *sbi;
2058 * We borrow i_block_reservation_lock to protect i_cached_extent
2060 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
2061 cex = &EXT4_I(inode)->i_cached_extent;
2062 sbi = EXT4_SB(inode->i_sb);
2064 /* has cache valid data? */
2065 if (cex->ec_len == 0)
2068 if (in_range(block, cex->ec_block, cex->ec_len)) {
2069 memcpy(ex, cex, sizeof(struct ext4_ext_cache));
2070 ext_debug("%u cached by %u:%u:%llu\n",
2072 cex->ec_block, cex->ec_len, cex->ec_start);
2076 trace_ext4_ext_in_cache(inode, block, ret);
2077 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
2082 * ext4_ext_in_cache()
2083 * Checks to see if the given block is in the cache.
2084 * If it is, the cached extent is stored in the given
2087 * @inode: The files inode
2088 * @block: The block to look for in the cache
2089 * @ex: Pointer where the cached extent will be stored
2090 * if it contains block
2092 * Return 0 if cache is invalid; 1 if the cache is valid
2095 ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block,
2096 struct ext4_extent *ex)
2098 struct ext4_ext_cache cex;
2101 if (ext4_ext_check_cache(inode, block, &cex)) {
2102 ex->ee_block = cpu_to_le32(cex.ec_block);
2103 ext4_ext_store_pblock(ex, cex.ec_start);
2104 ex->ee_len = cpu_to_le16(cex.ec_len);
2114 * removes index from the index block.
2116 static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
2117 struct ext4_ext_path *path, int depth)
2122 /* free index block */
2124 path = path + depth;
2125 leaf = ext4_idx_pblock(path->p_idx);
2126 if (unlikely(path->p_hdr->eh_entries == 0)) {
2127 EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0");
2130 err = ext4_ext_get_access(handle, inode, path);
2134 if (path->p_idx != EXT_LAST_INDEX(path->p_hdr)) {
2135 int len = EXT_LAST_INDEX(path->p_hdr) - path->p_idx;
2136 len *= sizeof(struct ext4_extent_idx);
2137 memmove(path->p_idx, path->p_idx + 1, len);
2140 le16_add_cpu(&path->p_hdr->eh_entries, -1);
2141 err = ext4_ext_dirty(handle, inode, path);
2144 ext_debug("index is empty, remove it, free block %llu\n", leaf);
2145 trace_ext4_ext_rm_idx(inode, leaf);
2147 ext4_free_blocks(handle, inode, NULL, leaf, 1,
2148 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
2150 while (--depth >= 0) {
2151 if (path->p_idx != EXT_FIRST_INDEX(path->p_hdr))
2154 err = ext4_ext_get_access(handle, inode, path);
2157 path->p_idx->ei_block = (path+1)->p_idx->ei_block;
2158 err = ext4_ext_dirty(handle, inode, path);
2166 * ext4_ext_calc_credits_for_single_extent:
2167 * This routine returns max. credits that needed to insert an extent
2168 * to the extent tree.
2169 * When pass the actual path, the caller should calculate credits
2172 int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks,
2173 struct ext4_ext_path *path)
2176 int depth = ext_depth(inode);
2179 /* probably there is space in leaf? */
2180 if (le16_to_cpu(path[depth].p_hdr->eh_entries)
2181 < le16_to_cpu(path[depth].p_hdr->eh_max)) {
2184 * There are some space in the leaf tree, no
2185 * need to account for leaf block credit
2187 * bitmaps and block group descriptor blocks
2188 * and other metadata blocks still need to be
2191 /* 1 bitmap, 1 block group descriptor */
2192 ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb);
2197 return ext4_chunk_trans_blocks(inode, nrblocks);
2201 * How many index/leaf blocks need to change/allocate to modify nrblocks?
2203 * if nrblocks are fit in a single extent (chunk flag is 1), then
2204 * in the worse case, each tree level index/leaf need to be changed
2205 * if the tree split due to insert a new extent, then the old tree
2206 * index/leaf need to be updated too
2208 * If the nrblocks are discontiguous, they could cause
2209 * the whole tree split more than once, but this is really rare.
2211 int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
2214 int depth = ext_depth(inode);
2224 static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
2225 struct ext4_extent *ex,
2226 ext4_fsblk_t *partial_cluster,
2227 ext4_lblk_t from, ext4_lblk_t to)
2229 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2230 unsigned short ee_len = ext4_ext_get_actual_len(ex);
2232 int flags = EXT4_FREE_BLOCKS_FORGET;
2234 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2235 flags |= EXT4_FREE_BLOCKS_METADATA;
2237 * For bigalloc file systems, we never free a partial cluster
2238 * at the beginning of the extent. Instead, we make a note
2239 * that we tried freeing the cluster, and check to see if we
2240 * need to free it on a subsequent call to ext4_remove_blocks,
2241 * or at the end of the ext4_truncate() operation.
2243 flags |= EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER;
2245 trace_ext4_remove_blocks(inode, ex, from, to, *partial_cluster);
2247 * If we have a partial cluster, and it's different from the
2248 * cluster of the last block, we need to explicitly free the
2249 * partial cluster here.
2251 pblk = ext4_ext_pblock(ex) + ee_len - 1;
2252 if (*partial_cluster && (EXT4_B2C(sbi, pblk) != *partial_cluster)) {
2253 ext4_free_blocks(handle, inode, NULL,
2254 EXT4_C2B(sbi, *partial_cluster),
2255 sbi->s_cluster_ratio, flags);
2256 *partial_cluster = 0;
2259 #ifdef EXTENTS_STATS
2261 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2262 spin_lock(&sbi->s_ext_stats_lock);
2263 sbi->s_ext_blocks += ee_len;
2264 sbi->s_ext_extents++;
2265 if (ee_len < sbi->s_ext_min)
2266 sbi->s_ext_min = ee_len;
2267 if (ee_len > sbi->s_ext_max)
2268 sbi->s_ext_max = ee_len;
2269 if (ext_depth(inode) > sbi->s_depth_max)
2270 sbi->s_depth_max = ext_depth(inode);
2271 spin_unlock(&sbi->s_ext_stats_lock);
2274 if (from >= le32_to_cpu(ex->ee_block)
2275 && to == le32_to_cpu(ex->ee_block) + ee_len - 1) {
2279 num = le32_to_cpu(ex->ee_block) + ee_len - from;
2280 pblk = ext4_ext_pblock(ex) + ee_len - num;
2281 ext_debug("free last %u blocks starting %llu\n", num, pblk);
2282 ext4_free_blocks(handle, inode, NULL, pblk, num, flags);
2284 * If the block range to be freed didn't start at the
2285 * beginning of a cluster, and we removed the entire
2286 * extent, save the partial cluster here, since we
2287 * might need to delete if we determine that the
2288 * truncate operation has removed all of the blocks in
2291 if (pblk & (sbi->s_cluster_ratio - 1) &&
2293 *partial_cluster = EXT4_B2C(sbi, pblk);
2295 *partial_cluster = 0;
2296 } else if (from == le32_to_cpu(ex->ee_block)
2297 && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
2303 start = ext4_ext_pblock(ex);
2305 ext_debug("free first %u blocks starting %llu\n", num, start);
2306 ext4_free_blocks(handle, inode, NULL, start, num, flags);
2309 printk(KERN_INFO "strange request: removal(2) "
2310 "%u-%u from %u:%u\n",
2311 from, to, le32_to_cpu(ex->ee_block), ee_len);
2318 * ext4_ext_rm_leaf() Removes the extents associated with the
2319 * blocks appearing between "start" and "end", and splits the extents
2320 * if "start" and "end" appear in the same extent
2322 * @handle: The journal handle
2323 * @inode: The files inode
2324 * @path: The path to the leaf
2325 * @start: The first block to remove
2326 * @end: The last block to remove
2329 ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
2330 struct ext4_ext_path *path, ext4_fsblk_t *partial_cluster,
2331 ext4_lblk_t start, ext4_lblk_t end)
2333 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2334 int err = 0, correct_index = 0;
2335 int depth = ext_depth(inode), credits;
2336 struct ext4_extent_header *eh;
2339 ext4_lblk_t ex_ee_block;
2340 unsigned short ex_ee_len;
2341 unsigned uninitialized = 0;
2342 struct ext4_extent *ex;
2344 /* the header must be checked already in ext4_ext_remove_space() */
2345 ext_debug("truncate since %u in leaf to %u\n", start, end);
2346 if (!path[depth].p_hdr)
2347 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
2348 eh = path[depth].p_hdr;
2349 if (unlikely(path[depth].p_hdr == NULL)) {
2350 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
2353 /* find where to start removing */
2354 ex = EXT_LAST_EXTENT(eh);
2356 ex_ee_block = le32_to_cpu(ex->ee_block);
2357 ex_ee_len = ext4_ext_get_actual_len(ex);
2359 trace_ext4_ext_rm_leaf(inode, start, ex, *partial_cluster);
2361 while (ex >= EXT_FIRST_EXTENT(eh) &&
2362 ex_ee_block + ex_ee_len > start) {
2364 if (ext4_ext_is_uninitialized(ex))
2369 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block,
2370 uninitialized, ex_ee_len);
2371 path[depth].p_ext = ex;
2373 a = ex_ee_block > start ? ex_ee_block : start;
2374 b = ex_ee_block+ex_ee_len - 1 < end ?
2375 ex_ee_block+ex_ee_len - 1 : end;
2377 ext_debug(" border %u:%u\n", a, b);
2379 /* If this extent is beyond the end of the hole, skip it */
2380 if (end < ex_ee_block) {
2382 ex_ee_block = le32_to_cpu(ex->ee_block);
2383 ex_ee_len = ext4_ext_get_actual_len(ex);
2385 } else if (b != ex_ee_block + ex_ee_len - 1) {
2386 EXT4_ERROR_INODE(inode," bad truncate %u:%u\n",
2390 } else if (a != ex_ee_block) {
2391 /* remove tail of the extent */
2392 num = a - ex_ee_block;
2394 /* remove whole extent: excellent! */
2398 * 3 for leaf, sb, and inode plus 2 (bmap and group
2399 * descriptor) for each block group; assume two block
2400 * groups plus ex_ee_len/blocks_per_block_group for
2403 credits = 7 + 2*(ex_ee_len/EXT4_BLOCKS_PER_GROUP(inode->i_sb));
2404 if (ex == EXT_FIRST_EXTENT(eh)) {
2406 credits += (ext_depth(inode)) + 1;
2408 credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
2410 err = ext4_ext_truncate_extend_restart(handle, inode, credits);
2414 err = ext4_ext_get_access(handle, inode, path + depth);
2418 err = ext4_remove_blocks(handle, inode, ex, partial_cluster,
2424 /* this extent is removed; mark slot entirely unused */
2425 ext4_ext_store_pblock(ex, 0);
2427 ex->ee_len = cpu_to_le16(num);
2429 * Do not mark uninitialized if all the blocks in the
2430 * extent have been removed.
2432 if (uninitialized && num)
2433 ext4_ext_mark_uninitialized(ex);
2435 * If the extent was completely released,
2436 * we need to remove it from the leaf
2439 if (end != EXT_MAX_BLOCKS - 1) {
2441 * For hole punching, we need to scoot all the
2442 * extents up when an extent is removed so that
2443 * we dont have blank extents in the middle
2445 memmove(ex, ex+1, (EXT_LAST_EXTENT(eh) - ex) *
2446 sizeof(struct ext4_extent));
2448 /* Now get rid of the one at the end */
2449 memset(EXT_LAST_EXTENT(eh), 0,
2450 sizeof(struct ext4_extent));
2452 le16_add_cpu(&eh->eh_entries, -1);
2454 *partial_cluster = 0;
2456 err = ext4_ext_dirty(handle, inode, path + depth);
2460 ext_debug("new extent: %u:%u:%llu\n", ex_ee_block, num,
2461 ext4_ext_pblock(ex));
2463 ex_ee_block = le32_to_cpu(ex->ee_block);
2464 ex_ee_len = ext4_ext_get_actual_len(ex);
2467 if (correct_index && eh->eh_entries)
2468 err = ext4_ext_correct_indexes(handle, inode, path);
2471 * If there is still a entry in the leaf node, check to see if
2472 * it references the partial cluster. This is the only place
2473 * where it could; if it doesn't, we can free the cluster.
2475 if (*partial_cluster && ex >= EXT_FIRST_EXTENT(eh) &&
2476 (EXT4_B2C(sbi, ext4_ext_pblock(ex) + ex_ee_len - 1) !=
2477 *partial_cluster)) {
2478 int flags = EXT4_FREE_BLOCKS_FORGET;
2480 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2481 flags |= EXT4_FREE_BLOCKS_METADATA;
2483 ext4_free_blocks(handle, inode, NULL,
2484 EXT4_C2B(sbi, *partial_cluster),
2485 sbi->s_cluster_ratio, flags);
2486 *partial_cluster = 0;
2489 /* if this leaf is free, then we should
2490 * remove it from index block above */
2491 if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
2492 err = ext4_ext_rm_idx(handle, inode, path, depth);
2499 * ext4_ext_more_to_rm:
2500 * returns 1 if current index has to be freed (even partial)
2503 ext4_ext_more_to_rm(struct ext4_ext_path *path)
2505 BUG_ON(path->p_idx == NULL);
2507 if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
2511 * if truncate on deeper level happened, it wasn't partial,
2512 * so we have to consider current index for truncation
2514 if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
2519 static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2522 struct super_block *sb = inode->i_sb;
2523 int depth = ext_depth(inode);
2524 struct ext4_ext_path *path = NULL;
2525 ext4_fsblk_t partial_cluster = 0;
2529 ext_debug("truncate since %u to %u\n", start, end);
2531 /* probably first extent we're gonna free will be last in block */
2532 handle = ext4_journal_start(inode, depth + 1);
2534 return PTR_ERR(handle);
2537 ext4_ext_invalidate_cache(inode);
2539 trace_ext4_ext_remove_space(inode, start, depth);
2542 * Check if we are removing extents inside the extent tree. If that
2543 * is the case, we are going to punch a hole inside the extent tree
2544 * so we have to check whether we need to split the extent covering
2545 * the last block to remove so we can easily remove the part of it
2546 * in ext4_ext_rm_leaf().
2548 if (end < EXT_MAX_BLOCKS - 1) {
2549 struct ext4_extent *ex;
2550 ext4_lblk_t ee_block;
2552 /* find extent for this block */
2553 path = ext4_ext_find_extent(inode, end, NULL);
2555 ext4_journal_stop(handle);
2556 return PTR_ERR(path);
2558 depth = ext_depth(inode);
2559 ex = path[depth].p_ext;
2561 ext4_ext_drop_refs(path);
2567 ee_block = le32_to_cpu(ex->ee_block);
2570 * See if the last block is inside the extent, if so split
2571 * the extent at 'end' block so we can easily remove the
2572 * tail of the first part of the split extent in
2573 * ext4_ext_rm_leaf().
2575 if (end >= ee_block &&
2576 end < ee_block + ext4_ext_get_actual_len(ex) - 1) {
2579 if (ext4_ext_is_uninitialized(ex))
2580 split_flag = EXT4_EXT_MARK_UNINIT1 |
2581 EXT4_EXT_MARK_UNINIT2;
2584 * Split the extent in two so that 'end' is the last
2585 * block in the first new extent
2587 err = ext4_split_extent_at(handle, inode, path,
2588 end + 1, split_flag,
2589 EXT4_GET_BLOCKS_PRE_IO |
2590 EXT4_GET_BLOCKS_PUNCH_OUT_EXT);
2599 * We start scanning from right side, freeing all the blocks
2600 * after i_size and walking into the tree depth-wise.
2602 depth = ext_depth(inode);
2607 le16_to_cpu(path[k].p_hdr->eh_entries)+1;
2609 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1),
2612 ext4_journal_stop(handle);
2615 path[0].p_depth = depth;
2616 path[0].p_hdr = ext_inode_hdr(inode);
2619 if (ext4_ext_check(inode, path[0].p_hdr, depth)) {
2626 while (i >= 0 && err == 0) {
2628 /* this is leaf block */
2629 err = ext4_ext_rm_leaf(handle, inode, path,
2630 &partial_cluster, start,
2632 /* root level has p_bh == NULL, brelse() eats this */
2633 brelse(path[i].p_bh);
2634 path[i].p_bh = NULL;
2639 /* this is index block */
2640 if (!path[i].p_hdr) {
2641 ext_debug("initialize header\n");
2642 path[i].p_hdr = ext_block_hdr(path[i].p_bh);
2645 if (!path[i].p_idx) {
2646 /* this level hasn't been touched yet */
2647 path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
2648 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
2649 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2651 le16_to_cpu(path[i].p_hdr->eh_entries));
2653 /* we were already here, see at next index */
2657 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2658 i, EXT_FIRST_INDEX(path[i].p_hdr),
2660 if (ext4_ext_more_to_rm(path + i)) {
2661 struct buffer_head *bh;
2662 /* go to the next level */
2663 ext_debug("move to level %d (block %llu)\n",
2664 i + 1, ext4_idx_pblock(path[i].p_idx));
2665 memset(path + i + 1, 0, sizeof(*path));
2666 bh = sb_bread(sb, ext4_idx_pblock(path[i].p_idx));
2668 /* should we reset i_size? */
2672 if (WARN_ON(i + 1 > depth)) {
2676 if (ext4_ext_check(inode, ext_block_hdr(bh),
2681 path[i + 1].p_bh = bh;
2683 /* save actual number of indexes since this
2684 * number is changed at the next iteration */
2685 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
2688 /* we finished processing this index, go up */
2689 if (path[i].p_hdr->eh_entries == 0 && i > 0) {
2690 /* index is empty, remove it;
2691 * handle must be already prepared by the
2692 * truncatei_leaf() */
2693 err = ext4_ext_rm_idx(handle, inode, path, i);
2695 /* root level has p_bh == NULL, brelse() eats this */
2696 brelse(path[i].p_bh);
2697 path[i].p_bh = NULL;
2699 ext_debug("return to level %d\n", i);
2703 trace_ext4_ext_remove_space_done(inode, start, depth, partial_cluster,
2704 path->p_hdr->eh_entries);
2706 /* If we still have something in the partial cluster and we have removed
2707 * even the first extent, then we should free the blocks in the partial
2708 * cluster as well. */
2709 if (partial_cluster && path->p_hdr->eh_entries == 0) {
2710 int flags = EXT4_FREE_BLOCKS_FORGET;
2712 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2713 flags |= EXT4_FREE_BLOCKS_METADATA;
2715 ext4_free_blocks(handle, inode, NULL,
2716 EXT4_C2B(EXT4_SB(sb), partial_cluster),
2717 EXT4_SB(sb)->s_cluster_ratio, flags);
2718 partial_cluster = 0;
2721 /* TODO: flexible tree reduction should be here */
2722 if (path->p_hdr->eh_entries == 0) {
2724 * truncate to zero freed all the tree,
2725 * so we need to correct eh_depth
2727 err = ext4_ext_get_access(handle, inode, path);
2729 ext_inode_hdr(inode)->eh_depth = 0;
2730 ext_inode_hdr(inode)->eh_max =
2731 cpu_to_le16(ext4_ext_space_root(inode, 0));
2732 err = ext4_ext_dirty(handle, inode, path);
2736 ext4_ext_drop_refs(path);
2738 if (err == -EAGAIN) {
2742 ext4_journal_stop(handle);
2748 * called at mount time
2750 void ext4_ext_init(struct super_block *sb)
2753 * possible initialization would be here
2756 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2757 #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
2758 printk(KERN_INFO "EXT4-fs: file extents enabled");
2759 #ifdef AGGRESSIVE_TEST
2760 printk(", aggressive tests");
2762 #ifdef CHECK_BINSEARCH
2763 printk(", check binsearch");
2765 #ifdef EXTENTS_STATS
2770 #ifdef EXTENTS_STATS
2771 spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
2772 EXT4_SB(sb)->s_ext_min = 1 << 30;
2773 EXT4_SB(sb)->s_ext_max = 0;
2779 * called at umount time
2781 void ext4_ext_release(struct super_block *sb)
2783 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2786 #ifdef EXTENTS_STATS
2787 if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
2788 struct ext4_sb_info *sbi = EXT4_SB(sb);
2789 printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2790 sbi->s_ext_blocks, sbi->s_ext_extents,
2791 sbi->s_ext_blocks / sbi->s_ext_extents);
2792 printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2793 sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
2798 /* FIXME!! we need to try to merge to left or right after zero-out */
2799 static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
2801 ext4_fsblk_t ee_pblock;
2802 unsigned int ee_len;
2805 ee_len = ext4_ext_get_actual_len(ex);
2806 ee_pblock = ext4_ext_pblock(ex);
2808 ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
2816 * ext4_split_extent_at() splits an extent at given block.
2818 * @handle: the journal handle
2819 * @inode: the file inode
2820 * @path: the path to the extent
2821 * @split: the logical block where the extent is splitted.
2822 * @split_flags: indicates if the extent could be zeroout if split fails, and
2823 * the states(init or uninit) of new extents.
2824 * @flags: flags used to insert new extent to extent tree.
2827 * Splits extent [a, b] into two extents [a, @split) and [@split, b], states
2828 * of which are deterimined by split_flag.
2830 * There are two cases:
2831 * a> the extent are splitted into two extent.
2832 * b> split is not needed, and just mark the extent.
2834 * return 0 on success.
2836 static int ext4_split_extent_at(handle_t *handle,
2837 struct inode *inode,
2838 struct ext4_ext_path *path,
2843 ext4_fsblk_t newblock;
2844 ext4_lblk_t ee_block;
2845 struct ext4_extent *ex, newex, orig_ex;
2846 struct ext4_extent *ex2 = NULL;
2847 unsigned int ee_len, depth;
2850 BUG_ON((split_flag & (EXT4_EXT_DATA_VALID1 | EXT4_EXT_DATA_VALID2)) ==
2851 (EXT4_EXT_DATA_VALID1 | EXT4_EXT_DATA_VALID2));
2853 ext_debug("ext4_split_extents_at: inode %lu, logical"
2854 "block %llu\n", inode->i_ino, (unsigned long long)split);
2856 ext4_ext_show_leaf(inode, path);
2858 depth = ext_depth(inode);
2859 ex = path[depth].p_ext;
2860 ee_block = le32_to_cpu(ex->ee_block);
2861 ee_len = ext4_ext_get_actual_len(ex);
2862 newblock = split - ee_block + ext4_ext_pblock(ex);
2864 BUG_ON(split < ee_block || split >= (ee_block + ee_len));
2866 err = ext4_ext_get_access(handle, inode, path + depth);
2870 if (split == ee_block) {
2872 * case b: block @split is the block that the extent begins with
2873 * then we just change the state of the extent, and splitting
2876 if (split_flag & EXT4_EXT_MARK_UNINIT2)
2877 ext4_ext_mark_uninitialized(ex);
2879 ext4_ext_mark_initialized(ex);
2881 if (!(flags & EXT4_GET_BLOCKS_PRE_IO))
2882 ext4_ext_try_to_merge(inode, path, ex);
2884 err = ext4_ext_dirty(handle, inode, path + depth);
2889 memcpy(&orig_ex, ex, sizeof(orig_ex));
2890 ex->ee_len = cpu_to_le16(split - ee_block);
2891 if (split_flag & EXT4_EXT_MARK_UNINIT1)
2892 ext4_ext_mark_uninitialized(ex);
2895 * path may lead to new leaf, not to original leaf any more
2896 * after ext4_ext_insert_extent() returns,
2898 err = ext4_ext_dirty(handle, inode, path + depth);
2900 goto fix_extent_len;
2903 ex2->ee_block = cpu_to_le32(split);
2904 ex2->ee_len = cpu_to_le16(ee_len - (split - ee_block));
2905 ext4_ext_store_pblock(ex2, newblock);
2906 if (split_flag & EXT4_EXT_MARK_UNINIT2)
2907 ext4_ext_mark_uninitialized(ex2);
2909 err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
2910 if (err == -ENOSPC && (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
2911 if (split_flag & (EXT4_EXT_DATA_VALID1|EXT4_EXT_DATA_VALID2)) {
2912 if (split_flag & EXT4_EXT_DATA_VALID1)
2913 err = ext4_ext_zeroout(inode, ex2);
2915 err = ext4_ext_zeroout(inode, ex);
2917 err = ext4_ext_zeroout(inode, &orig_ex);
2920 goto fix_extent_len;
2921 /* update the extent length and mark as initialized */
2922 ex->ee_len = cpu_to_le16(ee_len);
2923 ext4_ext_try_to_merge(inode, path, ex);
2924 err = ext4_ext_dirty(handle, inode, path + depth);
2927 goto fix_extent_len;
2930 ext4_ext_show_leaf(inode, path);
2934 ex->ee_len = orig_ex.ee_len;
2935 ext4_ext_dirty(handle, inode, path + depth);
2940 * ext4_split_extents() splits an extent and mark extent which is covered
2941 * by @map as split_flags indicates
2943 * It may result in splitting the extent into multiple extents (upto three)
2944 * There are three possibilities:
2945 * a> There is no split required
2946 * b> Splits in two extents: Split is happening at either end of the extent
2947 * c> Splits in three extents: Somone is splitting in middle of the extent
2950 static int ext4_split_extent(handle_t *handle,
2951 struct inode *inode,
2952 struct ext4_ext_path *path,
2953 struct ext4_map_blocks *map,
2957 ext4_lblk_t ee_block;
2958 struct ext4_extent *ex;
2959 unsigned int ee_len, depth;
2962 int split_flag1, flags1;
2964 depth = ext_depth(inode);
2965 ex = path[depth].p_ext;
2966 ee_block = le32_to_cpu(ex->ee_block);
2967 ee_len = ext4_ext_get_actual_len(ex);
2968 uninitialized = ext4_ext_is_uninitialized(ex);
2970 if (map->m_lblk + map->m_len < ee_block + ee_len) {
2971 split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT;
2972 flags1 = flags | EXT4_GET_BLOCKS_PRE_IO;
2974 split_flag1 |= EXT4_EXT_MARK_UNINIT1 |
2975 EXT4_EXT_MARK_UNINIT2;
2976 if (split_flag & EXT4_EXT_DATA_VALID2)
2977 split_flag1 |= EXT4_EXT_DATA_VALID1;
2978 err = ext4_split_extent_at(handle, inode, path,
2979 map->m_lblk + map->m_len, split_flag1, flags1);
2984 ext4_ext_drop_refs(path);
2985 path = ext4_ext_find_extent(inode, map->m_lblk, path);
2987 return PTR_ERR(path);
2989 if (map->m_lblk >= ee_block) {
2990 split_flag1 = split_flag & (EXT4_EXT_MAY_ZEROOUT |
2991 EXT4_EXT_DATA_VALID2);
2993 split_flag1 |= EXT4_EXT_MARK_UNINIT1;
2994 if (split_flag & EXT4_EXT_MARK_UNINIT2)
2995 split_flag1 |= EXT4_EXT_MARK_UNINIT2;
2996 err = ext4_split_extent_at(handle, inode, path,
2997 map->m_lblk, split_flag1, flags);
3002 ext4_ext_show_leaf(inode, path);
3004 return err ? err : map->m_len;
3007 #define EXT4_EXT_ZERO_LEN 7
3009 * This function is called by ext4_ext_map_blocks() if someone tries to write
3010 * to an uninitialized extent. It may result in splitting the uninitialized
3011 * extent into multiple extents (up to three - one initialized and two
3013 * There are three possibilities:
3014 * a> There is no split required: Entire extent should be initialized
3015 * b> Splits in two extents: Write is happening at either end of the extent
3016 * c> Splits in three extents: Somone is writing in middle of the extent
3019 * - The extent pointed to by 'path' is uninitialized.
3020 * - The extent pointed to by 'path' contains a superset
3021 * of the logical span [map->m_lblk, map->m_lblk + map->m_len).
3023 * Post-conditions on success:
3024 * - the returned value is the number of blocks beyond map->l_lblk
3025 * that are allocated and initialized.
3026 * It is guaranteed to be >= map->m_len.
3028 static int ext4_ext_convert_to_initialized(handle_t *handle,
3029 struct inode *inode,
3030 struct ext4_map_blocks *map,
3031 struct ext4_ext_path *path)
3033 struct ext4_extent_header *eh;
3034 struct ext4_map_blocks split_map;
3035 struct ext4_extent zero_ex;
3036 struct ext4_extent *ex;
3037 ext4_lblk_t ee_block, eof_block;
3038 unsigned int ee_len, depth;
3043 ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
3044 "block %llu, max_blocks %u\n", inode->i_ino,
3045 (unsigned long long)map->m_lblk, map->m_len);
3047 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
3048 inode->i_sb->s_blocksize_bits;
3049 if (eof_block < map->m_lblk + map->m_len)
3050 eof_block = map->m_lblk + map->m_len;
3052 depth = ext_depth(inode);
3053 eh = path[depth].p_hdr;
3054 ex = path[depth].p_ext;
3055 ee_block = le32_to_cpu(ex->ee_block);
3056 ee_len = ext4_ext_get_actual_len(ex);
3057 allocated = ee_len - (map->m_lblk - ee_block);
3059 trace_ext4_ext_convert_to_initialized_enter(inode, map, ex);
3061 /* Pre-conditions */
3062 BUG_ON(!ext4_ext_is_uninitialized(ex));
3063 BUG_ON(!in_range(map->m_lblk, ee_block, ee_len));
3066 * Attempt to transfer newly initialized blocks from the currently
3067 * uninitialized extent to its left neighbor. This is much cheaper
3068 * than an insertion followed by a merge as those involve costly
3069 * memmove() calls. This is the common case in steady state for
3070 * workloads doing fallocate(FALLOC_FL_KEEP_SIZE) followed by append
3073 * Limitations of the current logic:
3074 * - L1: we only deal with writes at the start of the extent.
3075 * The approach could be extended to writes at the end
3076 * of the extent but this scenario was deemed less common.
3077 * - L2: we do not deal with writes covering the whole extent.
3078 * This would require removing the extent if the transfer
3080 * - L3: we only attempt to merge with an extent stored in the
3081 * same extent tree node.
3083 if ((map->m_lblk == ee_block) && /*L1*/
3084 (map->m_len < ee_len) && /*L2*/
3085 (ex > EXT_FIRST_EXTENT(eh))) { /*L3*/
3086 struct ext4_extent *prev_ex;
3087 ext4_lblk_t prev_lblk;
3088 ext4_fsblk_t prev_pblk, ee_pblk;
3089 unsigned int prev_len, write_len;
3092 prev_lblk = le32_to_cpu(prev_ex->ee_block);
3093 prev_len = ext4_ext_get_actual_len(prev_ex);
3094 prev_pblk = ext4_ext_pblock(prev_ex);
3095 ee_pblk = ext4_ext_pblock(ex);
3096 write_len = map->m_len;
3099 * A transfer of blocks from 'ex' to 'prev_ex' is allowed
3100 * upon those conditions:
3101 * - C1: prev_ex is initialized,
3102 * - C2: prev_ex is logically abutting ex,
3103 * - C3: prev_ex is physically abutting ex,
3104 * - C4: prev_ex can receive the additional blocks without
3105 * overflowing the (initialized) length limit.
3107 if ((!ext4_ext_is_uninitialized(prev_ex)) && /*C1*/
3108 ((prev_lblk + prev_len) == ee_block) && /*C2*/
3109 ((prev_pblk + prev_len) == ee_pblk) && /*C3*/
3110 (prev_len < (EXT_INIT_MAX_LEN - write_len))) { /*C4*/
3111 err = ext4_ext_get_access(handle, inode, path + depth);
3115 trace_ext4_ext_convert_to_initialized_fastpath(inode,
3118 /* Shift the start of ex by 'write_len' blocks */
3119 ex->ee_block = cpu_to_le32(ee_block + write_len);
3120 ext4_ext_store_pblock(ex, ee_pblk + write_len);
3121 ex->ee_len = cpu_to_le16(ee_len - write_len);
3122 ext4_ext_mark_uninitialized(ex); /* Restore the flag */
3124 /* Extend prev_ex by 'write_len' blocks */
3125 prev_ex->ee_len = cpu_to_le16(prev_len + write_len);
3127 /* Mark the block containing both extents as dirty */
3128 ext4_ext_dirty(handle, inode, path + depth);
3130 /* Update path to point to the right extent */
3131 path[depth].p_ext = prev_ex;
3133 /* Result: number of initialized blocks past m_lblk */
3134 allocated = write_len;
3139 WARN_ON(map->m_lblk < ee_block);
3141 * It is safe to convert extent to initialized via explicit
3142 * zeroout only if extent is fully insde i_size or new_size.
3144 split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
3146 /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
3147 if (ee_len <= 2*EXT4_EXT_ZERO_LEN &&
3148 (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
3149 err = ext4_ext_zeroout(inode, ex);
3153 err = ext4_ext_get_access(handle, inode, path + depth);
3156 ext4_ext_mark_initialized(ex);
3157 ext4_ext_try_to_merge(inode, path, ex);
3158 err = ext4_ext_dirty(handle, inode, path + depth);
3164 * 1. split the extent into three extents.
3165 * 2. split the extent into two extents, zeroout the first half.
3166 * 3. split the extent into two extents, zeroout the second half.
3167 * 4. split the extent into two extents with out zeroout.
3169 split_map.m_lblk = map->m_lblk;
3170 split_map.m_len = map->m_len;
3172 if (allocated > map->m_len) {
3173 if (allocated <= EXT4_EXT_ZERO_LEN &&
3174 (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
3177 cpu_to_le32(map->m_lblk);
3178 zero_ex.ee_len = cpu_to_le16(allocated);
3179 ext4_ext_store_pblock(&zero_ex,
3180 ext4_ext_pblock(ex) + map->m_lblk - ee_block);
3181 err = ext4_ext_zeroout(inode, &zero_ex);
3184 split_map.m_lblk = map->m_lblk;
3185 split_map.m_len = allocated;
3186 } else if ((map->m_lblk - ee_block + map->m_len <
3187 EXT4_EXT_ZERO_LEN) &&
3188 (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
3190 if (map->m_lblk != ee_block) {
3191 zero_ex.ee_block = ex->ee_block;
3192 zero_ex.ee_len = cpu_to_le16(map->m_lblk -
3194 ext4_ext_store_pblock(&zero_ex,
3195 ext4_ext_pblock(ex));
3196 err = ext4_ext_zeroout(inode, &zero_ex);
3201 split_map.m_lblk = ee_block;
3202 split_map.m_len = map->m_lblk - ee_block + map->m_len;
3203 allocated = map->m_len;
3207 allocated = ext4_split_extent(handle, inode, path,
3208 &split_map, split_flag, 0);
3213 return err ? err : allocated;
3217 * This function is called by ext4_ext_map_blocks() from
3218 * ext4_get_blocks_dio_write() when DIO to write
3219 * to an uninitialized extent.
3221 * Writing to an uninitialized extent may result in splitting the uninitialized
3222 * extent into multiple /initialized uninitialized extents (up to three)
3223 * There are three possibilities:
3224 * a> There is no split required: Entire extent should be uninitialized
3225 * b> Splits in two extents: Write is happening at either end of the extent
3226 * c> Splits in three extents: Somone is writing in middle of the extent
3228 * One of more index blocks maybe needed if the extent tree grow after
3229 * the uninitialized extent split. To prevent ENOSPC occur at the IO
3230 * complete, we need to split the uninitialized extent before DIO submit
3231 * the IO. The uninitialized extent called at this time will be split
3232 * into three uninitialized extent(at most). After IO complete, the part
3233 * being filled will be convert to initialized by the end_io callback function
3234 * via ext4_convert_unwritten_extents().
3236 * Returns the size of uninitialized extent to be written on success.
3238 static int ext4_split_unwritten_extents(handle_t *handle,
3239 struct inode *inode,
3240 struct ext4_map_blocks *map,
3241 struct ext4_ext_path *path,
3244 ext4_lblk_t eof_block;
3245 ext4_lblk_t ee_block;
3246 struct ext4_extent *ex;
3247 unsigned int ee_len;
3248 int split_flag = 0, depth;
3250 ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
3251 "block %llu, max_blocks %u\n", inode->i_ino,
3252 (unsigned long long)map->m_lblk, map->m_len);
3254 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
3255 inode->i_sb->s_blocksize_bits;
3256 if (eof_block < map->m_lblk + map->m_len)
3257 eof_block = map->m_lblk + map->m_len;
3259 * It is safe to convert extent to initialized via explicit
3260 * zeroout only if extent is fully insde i_size or new_size.
3262 depth = ext_depth(inode);
3263 ex = path[depth].p_ext;
3264 ee_block = le32_to_cpu(ex->ee_block);
3265 ee_len = ext4_ext_get_actual_len(ex);
3267 split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
3268 split_flag |= EXT4_EXT_MARK_UNINIT2;
3269 if (flags & EXT4_GET_BLOCKS_CONVERT)
3270 split_flag |= EXT4_EXT_DATA_VALID2;
3271 flags |= EXT4_GET_BLOCKS_PRE_IO;
3272 return ext4_split_extent(handle, inode, path, map, split_flag, flags);
3275 static int ext4_convert_unwritten_extents_endio(handle_t *handle,
3276 struct inode *inode,
3277 struct ext4_map_blocks *map,
3278 struct ext4_ext_path *path)
3280 struct ext4_extent *ex;
3281 ext4_lblk_t ee_block;
3282 unsigned int ee_len;
3286 depth = ext_depth(inode);
3287 ex = path[depth].p_ext;
3288 ee_block = le32_to_cpu(ex->ee_block);
3289 ee_len = ext4_ext_get_actual_len(ex);
3291 ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical"
3292 "block %llu, max_blocks %u\n", inode->i_ino,
3293 (unsigned long long)ee_block, ee_len);
3295 /* If extent is larger than requested then split is required */
3296 if (ee_block != map->m_lblk || ee_len > map->m_len) {
3297 err = ext4_split_unwritten_extents(handle, inode, map, path,
3298 EXT4_GET_BLOCKS_CONVERT);
3301 ext4_ext_drop_refs(path);
3302 path = ext4_ext_find_extent(inode, map->m_lblk, path);
3304 err = PTR_ERR(path);
3307 depth = ext_depth(inode);
3308 ex = path[depth].p_ext;
3311 err = ext4_ext_get_access(handle, inode, path + depth);
3314 /* first mark the extent as initialized */
3315 ext4_ext_mark_initialized(ex);
3317 /* note: ext4_ext_correct_indexes() isn't needed here because
3318 * borders are not changed
3320 ext4_ext_try_to_merge(inode, path, ex);
3322 /* Mark modified extent as dirty */
3323 err = ext4_ext_dirty(handle, inode, path + depth);
3325 ext4_ext_show_leaf(inode, path);
3329 static void unmap_underlying_metadata_blocks(struct block_device *bdev,
3330 sector_t block, int count)
3333 for (i = 0; i < count; i++)
3334 unmap_underlying_metadata(bdev, block + i);
3338 * Handle EOFBLOCKS_FL flag, clearing it if necessary
3340 static int check_eofblocks_fl(handle_t *handle, struct inode *inode,
3342 struct ext4_ext_path *path,
3346 struct ext4_extent_header *eh;
3347 struct ext4_extent *last_ex;
3349 if (!ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
3352 depth = ext_depth(inode);
3353 eh = path[depth].p_hdr;
3355 if (unlikely(!eh->eh_entries)) {
3356 EXT4_ERROR_INODE(inode, "eh->eh_entries == 0 and "
3357 "EOFBLOCKS_FL set");
3360 last_ex = EXT_LAST_EXTENT(eh);
3362 * We should clear the EOFBLOCKS_FL flag if we are writing the
3363 * last block in the last extent in the file. We test this by
3364 * first checking to see if the caller to
3365 * ext4_ext_get_blocks() was interested in the last block (or
3366 * a block beyond the last block) in the current extent. If
3367 * this turns out to be false, we can bail out from this
3368 * function immediately.
3370 if (lblk + len < le32_to_cpu(last_ex->ee_block) +
3371 ext4_ext_get_actual_len(last_ex))
3374 * If the caller does appear to be planning to write at or
3375 * beyond the end of the current extent, we then test to see
3376 * if the current extent is the last extent in the file, by
3377 * checking to make sure it was reached via the rightmost node
3378 * at each level of the tree.
3380 for (i = depth-1; i >= 0; i--)
3381 if (path[i].p_idx != EXT_LAST_INDEX(path[i].p_hdr))
3383 ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
3384 return ext4_mark_inode_dirty(handle, inode);
3388 * ext4_find_delalloc_range: find delayed allocated block in the given range.
3390 * Goes through the buffer heads in the range [lblk_start, lblk_end] and returns
3391 * whether there are any buffers marked for delayed allocation. It returns '1'
3392 * on the first delalloc'ed buffer head found. If no buffer head in the given
3393 * range is marked for delalloc, it returns 0.
3394 * lblk_start should always be <= lblk_end.
3395 * search_hint_reverse is to indicate that searching in reverse from lblk_end to
3396 * lblk_start might be more efficient (i.e., we will likely hit the delalloc'ed
3397 * block sooner). This is useful when blocks are truncated sequentially from
3398 * lblk_start towards lblk_end.
3400 static int ext4_find_delalloc_range(struct inode *inode,
3401 ext4_lblk_t lblk_start,
3402 ext4_lblk_t lblk_end,
3403 int search_hint_reverse)
3405 struct address_space *mapping = inode->i_mapping;
3406 struct buffer_head *head, *bh = NULL;
3408 ext4_lblk_t i, pg_lblk;
3411 /* reverse search wont work if fs block size is less than page size */
3412 if (inode->i_blkbits < PAGE_CACHE_SHIFT)
3413 search_hint_reverse = 0;
3415 if (search_hint_reverse)
3420 index = i >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
3422 while ((i >= lblk_start) && (i <= lblk_end)) {
3423 page = find_get_page(mapping, index);
3427 if (!page_has_buffers(page))
3430 head = page_buffers(page);
3435 pg_lblk = index << (PAGE_CACHE_SHIFT -
3438 if (unlikely(pg_lblk < lblk_start)) {
3440 * This is possible when fs block size is less
3441 * than page size and our cluster starts/ends in
3442 * middle of the page. So we need to skip the
3443 * initial few blocks till we reach the 'lblk'
3449 /* Check if the buffer is delayed allocated and that it
3450 * is not yet mapped. (when da-buffers are mapped during
3451 * their writeout, their da_mapped bit is set.)
3453 if (buffer_delay(bh) && !buffer_da_mapped(bh)) {
3454 page_cache_release(page);
3455 trace_ext4_find_delalloc_range(inode,
3456 lblk_start, lblk_end,
3457 search_hint_reverse,
3461 if (search_hint_reverse)
3465 } while ((i >= lblk_start) && (i <= lblk_end) &&
3466 ((bh = bh->b_this_page) != head));
3469 page_cache_release(page);
3471 * Move to next page. 'i' will be the first lblk in the next
3474 if (search_hint_reverse)
3478 i = index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
3481 trace_ext4_find_delalloc_range(inode, lblk_start, lblk_end,
3482 search_hint_reverse, 0, 0);
3486 int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk,
3487 int search_hint_reverse)
3489 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3490 ext4_lblk_t lblk_start, lblk_end;
3491 lblk_start = lblk & (~(sbi->s_cluster_ratio - 1));
3492 lblk_end = lblk_start + sbi->s_cluster_ratio - 1;
3494 return ext4_find_delalloc_range(inode, lblk_start, lblk_end,
3495 search_hint_reverse);
3499 * Determines how many complete clusters (out of those specified by the 'map')
3500 * are under delalloc and were reserved quota for.
3501 * This function is called when we are writing out the blocks that were
3502 * originally written with their allocation delayed, but then the space was
3503 * allocated using fallocate() before the delayed allocation could be resolved.
3504 * The cases to look for are:
3505 * ('=' indicated delayed allocated blocks
3506 * '-' indicates non-delayed allocated blocks)
3507 * (a) partial clusters towards beginning and/or end outside of allocated range
3508 * are not delalloc'ed.
3510 * |----c---=|====c====|====c====|===-c----|
3511 * |++++++ allocated ++++++|
3512 * ==> 4 complete clusters in above example
3514 * (b) partial cluster (outside of allocated range) towards either end is
3515 * marked for delayed allocation. In this case, we will exclude that
3518 * |----====c========|========c========|
3519 * |++++++ allocated ++++++|
3520 * ==> 1 complete clusters in above example
3523 * |================c================|
3524 * |++++++ allocated ++++++|
3525 * ==> 0 complete clusters in above example
3527 * The ext4_da_update_reserve_space will be called only if we
3528 * determine here that there were some "entire" clusters that span
3529 * this 'allocated' range.
3530 * In the non-bigalloc case, this function will just end up returning num_blks
3531 * without ever calling ext4_find_delalloc_range.
3534 get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start,
3535 unsigned int num_blks)
3537 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3538 ext4_lblk_t alloc_cluster_start, alloc_cluster_end;
3539 ext4_lblk_t lblk_from, lblk_to, c_offset;
3540 unsigned int allocated_clusters = 0;
3542 alloc_cluster_start = EXT4_B2C(sbi, lblk_start);
3543 alloc_cluster_end = EXT4_B2C(sbi, lblk_start + num_blks - 1);
3545 /* max possible clusters for this allocation */
3546 allocated_clusters = alloc_cluster_end - alloc_cluster_start + 1;
3548 trace_ext4_get_reserved_cluster_alloc(inode, lblk_start, num_blks);
3550 /* Check towards left side */
3551 c_offset = lblk_start & (sbi->s_cluster_ratio - 1);
3553 lblk_from = lblk_start & (~(sbi->s_cluster_ratio - 1));
3554 lblk_to = lblk_from + c_offset - 1;
3556 if (ext4_find_delalloc_range(inode, lblk_from, lblk_to, 0))
3557 allocated_clusters--;
3560 /* Now check towards right. */
3561 c_offset = (lblk_start + num_blks) & (sbi->s_cluster_ratio - 1);
3562 if (allocated_clusters && c_offset) {
3563 lblk_from = lblk_start + num_blks;
3564 lblk_to = lblk_from + (sbi->s_cluster_ratio - c_offset) - 1;
3566 if (ext4_find_delalloc_range(inode, lblk_from, lblk_to, 0))
3567 allocated_clusters--;
3570 return allocated_clusters;
3574 ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
3575 struct ext4_map_blocks *map,
3576 struct ext4_ext_path *path, int flags,
3577 unsigned int allocated, ext4_fsblk_t newblock)
3581 ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
3583 ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical"
3584 "block %llu, max_blocks %u, flags %d, allocated %u",
3585 inode->i_ino, (unsigned long long)map->m_lblk, map->m_len,
3587 ext4_ext_show_leaf(inode, path);
3589 trace_ext4_ext_handle_uninitialized_extents(inode, map, allocated,
3592 /* get_block() before submit the IO, split the extent */
3593 if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
3594 ret = ext4_split_unwritten_extents(handle, inode, map,
3597 * Flag the inode(non aio case) or end_io struct (aio case)
3598 * that this IO needs to conversion to written when IO is
3602 ext4_set_io_unwritten_flag(inode, io);
3604 ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
3605 if (ext4_should_dioread_nolock(inode))
3606 map->m_flags |= EXT4_MAP_UNINIT;
3609 /* IO end_io complete, convert the filled extent to written */
3610 if ((flags & EXT4_GET_BLOCKS_CONVERT)) {
3611 ret = ext4_convert_unwritten_extents_endio(handle, inode, map,
3614 ext4_update_inode_fsync_trans(handle, inode, 1);
3615 err = check_eofblocks_fl(handle, inode, map->m_lblk,
3621 /* buffered IO case */
3623 * repeat fallocate creation request
3624 * we already have an unwritten extent
3626 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
3629 /* buffered READ or buffered write_begin() lookup */
3630 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
3632 * We have blocks reserved already. We
3633 * return allocated blocks so that delalloc
3634 * won't do block reservation for us. But
3635 * the buffer head will be unmapped so that
3636 * a read from the block returns 0s.
3638 map->m_flags |= EXT4_MAP_UNWRITTEN;
3642 /* buffered write, writepage time, convert*/
3643 ret = ext4_ext_convert_to_initialized(handle, inode, map, path);
3645 ext4_update_inode_fsync_trans(handle, inode, 1);
3652 map->m_flags |= EXT4_MAP_NEW;
3654 * if we allocated more blocks than requested
3655 * we need to make sure we unmap the extra block
3656 * allocated. The actual needed block will get
3657 * unmapped later when we find the buffer_head marked
3660 if (allocated > map->m_len) {
3661 unmap_underlying_metadata_blocks(inode->i_sb->s_bdev,
3662 newblock + map->m_len,
3663 allocated - map->m_len);
3664 allocated = map->m_len;
3668 * If we have done fallocate with the offset that is already
3669 * delayed allocated, we would have block reservation
3670 * and quota reservation done in the delayed write path.
3671 * But fallocate would have already updated quota and block
3672 * count for this offset. So cancel these reservation
3674 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
3675 unsigned int reserved_clusters;
3676 reserved_clusters = get_reserved_cluster_alloc(inode,
3677 map->m_lblk, map->m_len);
3678 if (reserved_clusters)
3679 ext4_da_update_reserve_space(inode,
3685 map->m_flags |= EXT4_MAP_MAPPED;
3686 if ((flags & EXT4_GET_BLOCKS_KEEP_SIZE) == 0) {
3687 err = check_eofblocks_fl(handle, inode, map->m_lblk, path,
3693 if (allocated > map->m_len)
3694 allocated = map->m_len;
3695 ext4_ext_show_leaf(inode, path);
3696 map->m_pblk = newblock;
3697 map->m_len = allocated;
3700 ext4_ext_drop_refs(path);
3703 return err ? err : allocated;
3707 * get_implied_cluster_alloc - check to see if the requested
3708 * allocation (in the map structure) overlaps with a cluster already
3709 * allocated in an extent.
3710 * @sb The filesystem superblock structure
3711 * @map The requested lblk->pblk mapping
3712 * @ex The extent structure which might contain an implied
3713 * cluster allocation
3715 * This function is called by ext4_ext_map_blocks() after we failed to
3716 * find blocks that were already in the inode's extent tree. Hence,
3717 * we know that the beginning of the requested region cannot overlap
3718 * the extent from the inode's extent tree. There are three cases we
3719 * want to catch. The first is this case:
3721 * |--- cluster # N--|
3722 * |--- extent ---| |---- requested region ---|
3725 * The second case that we need to test for is this one:
3727 * |--------- cluster # N ----------------|
3728 * |--- requested region --| |------- extent ----|
3729 * |=======================|
3731 * The third case is when the requested region lies between two extents
3732 * within the same cluster:
3733 * |------------- cluster # N-------------|
3734 * |----- ex -----| |---- ex_right ----|
3735 * |------ requested region ------|
3736 * |================|
3738 * In each of the above cases, we need to set the map->m_pblk and
3739 * map->m_len so it corresponds to the return the extent labelled as
3740 * "|====|" from cluster #N, since it is already in use for data in
3741 * cluster EXT4_B2C(sbi, map->m_lblk). We will then return 1 to
3742 * signal to ext4_ext_map_blocks() that map->m_pblk should be treated
3743 * as a new "allocated" block region. Otherwise, we will return 0 and
3744 * ext4_ext_map_blocks() will then allocate one or more new clusters
3745 * by calling ext4_mb_new_blocks().
3747 static int get_implied_cluster_alloc(struct super_block *sb,
3748 struct ext4_map_blocks *map,
3749 struct ext4_extent *ex,
3750 struct ext4_ext_path *path)
3752 struct ext4_sb_info *sbi = EXT4_SB(sb);
3753 ext4_lblk_t c_offset = map->m_lblk & (sbi->s_cluster_ratio-1);
3754 ext4_lblk_t ex_cluster_start, ex_cluster_end;
3755 ext4_lblk_t rr_cluster_start, rr_cluster_end;
3756 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
3757 ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
3758 unsigned short ee_len = ext4_ext_get_actual_len(ex);
3760 /* The extent passed in that we are trying to match */
3761 ex_cluster_start = EXT4_B2C(sbi, ee_block);
3762 ex_cluster_end = EXT4_B2C(sbi, ee_block + ee_len - 1);
3764 /* The requested region passed into ext4_map_blocks() */
3765 rr_cluster_start = EXT4_B2C(sbi, map->m_lblk);
3766 rr_cluster_end = EXT4_B2C(sbi, map->m_lblk + map->m_len - 1);
3768 if ((rr_cluster_start == ex_cluster_end) ||
3769 (rr_cluster_start == ex_cluster_start)) {
3770 if (rr_cluster_start == ex_cluster_end)
3771 ee_start += ee_len - 1;
3772 map->m_pblk = (ee_start & ~(sbi->s_cluster_ratio - 1)) +
3774 map->m_len = min(map->m_len,
3775 (unsigned) sbi->s_cluster_ratio - c_offset);
3777 * Check for and handle this case:
3779 * |--------- cluster # N-------------|
3780 * |------- extent ----|
3781 * |--- requested region ---|
3785 if (map->m_lblk < ee_block)
3786 map->m_len = min(map->m_len, ee_block - map->m_lblk);
3789 * Check for the case where there is already another allocated
3790 * block to the right of 'ex' but before the end of the cluster.
3792 * |------------- cluster # N-------------|
3793 * |----- ex -----| |---- ex_right ----|
3794 * |------ requested region ------|
3795 * |================|
3797 if (map->m_lblk > ee_block) {
3798 ext4_lblk_t next = ext4_ext_next_allocated_block(path);
3799 map->m_len = min(map->m_len, next - map->m_lblk);
3802 trace_ext4_get_implied_cluster_alloc_exit(sb, map, 1);
3806 trace_ext4_get_implied_cluster_alloc_exit(sb, map, 0);
3812 * Block allocation/map/preallocation routine for extents based files
3815 * Need to be called with
3816 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
3817 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
3819 * return > 0, number of of blocks already mapped/allocated
3820 * if create == 0 and these are pre-allocated blocks
3821 * buffer head is unmapped
3822 * otherwise blocks are mapped
3824 * return = 0, if plain look up failed (blocks have not been allocated)
3825 * buffer head is unmapped
3827 * return < 0, error case.
3829 int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3830 struct ext4_map_blocks *map, int flags)
3832 struct ext4_ext_path *path = NULL;
3833 struct ext4_extent newex, *ex, *ex2;
3834 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3835 ext4_fsblk_t newblock = 0;
3836 int free_on_err = 0, err = 0, depth, ret;
3837 unsigned int allocated = 0, offset = 0;
3838 unsigned int allocated_clusters = 0;
3839 unsigned int punched_out = 0;
3840 unsigned int result = 0;
3841 struct ext4_allocation_request ar;
3842 ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
3843 ext4_lblk_t cluster_offset;
3845 ext_debug("blocks %u/%u requested for inode %lu\n",
3846 map->m_lblk, map->m_len, inode->i_ino);
3847 trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags);
3849 /* check in cache */
3850 if (!(flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) &&
3851 ext4_ext_in_cache(inode, map->m_lblk, &newex)) {
3852 if (!newex.ee_start_lo && !newex.ee_start_hi) {
3853 if ((sbi->s_cluster_ratio > 1) &&
3854 ext4_find_delalloc_cluster(inode, map->m_lblk, 0))
3855 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
3857 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
3859 * block isn't allocated yet and
3860 * user doesn't want to allocate it
3864 /* we should allocate requested block */
3866 /* block is already allocated */
3867 if (sbi->s_cluster_ratio > 1)
3868 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
3869 newblock = map->m_lblk
3870 - le32_to_cpu(newex.ee_block)
3871 + ext4_ext_pblock(&newex);
3872 /* number of remaining blocks in the extent */
3873 allocated = ext4_ext_get_actual_len(&newex) -
3874 (map->m_lblk - le32_to_cpu(newex.ee_block));
3879 /* find extent for this block */
3880 path = ext4_ext_find_extent(inode, map->m_lblk, NULL);
3882 err = PTR_ERR(path);
3887 depth = ext_depth(inode);
3890 * consistent leaf must not be empty;
3891 * this situation is possible, though, _during_ tree modification;
3892 * this is why assert can't be put in ext4_ext_find_extent()
3894 if (unlikely(path[depth].p_ext == NULL && depth != 0)) {
3895 EXT4_ERROR_INODE(inode, "bad extent address "
3896 "lblock: %lu, depth: %d pblock %lld",
3897 (unsigned long) map->m_lblk, depth,
3898 path[depth].p_block);
3903 ex = path[depth].p_ext;
3905 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
3906 ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
3907 unsigned short ee_len;
3910 * Uninitialized extents are treated as holes, except that
3911 * we split out initialized portions during a write.
3913 ee_len = ext4_ext_get_actual_len(ex);
3915 trace_ext4_ext_show_extent(inode, ee_block, ee_start, ee_len);
3917 /* if found extent covers block, simply return it */
3918 if (in_range(map->m_lblk, ee_block, ee_len)) {
3919 struct ext4_map_blocks punch_map;
3920 ext4_fsblk_t partial_cluster = 0;
3922 newblock = map->m_lblk - ee_block + ee_start;
3923 /* number of remaining blocks in the extent */
3924 allocated = ee_len - (map->m_lblk - ee_block);
3925 ext_debug("%u fit into %u:%d -> %llu\n", map->m_lblk,
3926 ee_block, ee_len, newblock);
3928 if ((flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) == 0) {
3930 * Do not put uninitialized extent
3933 if (!ext4_ext_is_uninitialized(ex)) {
3934 ext4_ext_put_in_cache(inode, ee_block,
3938 ret = ext4_ext_handle_uninitialized_extents(
3939 handle, inode, map, path, flags,
3940 allocated, newblock);
3945 * Punch out the map length, but only to the
3948 punched_out = allocated < map->m_len ?
3949 allocated : map->m_len;
3952 * Sense extents need to be converted to
3953 * uninitialized, they must fit in an
3954 * uninitialized extent
3956 if (punched_out > EXT_UNINIT_MAX_LEN)
3957 punched_out = EXT_UNINIT_MAX_LEN;
3959 punch_map.m_lblk = map->m_lblk;
3960 punch_map.m_pblk = newblock;
3961 punch_map.m_len = punched_out;
3962 punch_map.m_flags = 0;
3964 /* Check to see if the extent needs to be split */
3965 if (punch_map.m_len != ee_len ||
3966 punch_map.m_lblk != ee_block) {
3968 ret = ext4_split_extent(handle, inode,
3969 path, &punch_map, 0,
3970 EXT4_GET_BLOCKS_PUNCH_OUT_EXT |
3971 EXT4_GET_BLOCKS_PRE_IO);
3978 * find extent for the block at
3979 * the start of the hole
3981 ext4_ext_drop_refs(path);
3984 path = ext4_ext_find_extent(inode,
3987 err = PTR_ERR(path);
3992 depth = ext_depth(inode);
3993 ex = path[depth].p_ext;
3994 ee_len = ext4_ext_get_actual_len(ex);
3995 ee_block = le32_to_cpu(ex->ee_block);
3996 ee_start = ext4_ext_pblock(ex);
4000 ext4_ext_mark_uninitialized(ex);
4002 ext4_ext_invalidate_cache(inode);
4004 err = ext4_ext_rm_leaf(handle, inode, path,
4005 &partial_cluster, map->m_lblk,
4006 map->m_lblk + punched_out);
4008 if (!err && path->p_hdr->eh_entries == 0) {
4010 * Punch hole freed all of this sub tree,
4011 * so we need to correct eh_depth
4013 err = ext4_ext_get_access(handle, inode, path);
4015 ext_inode_hdr(inode)->eh_depth = 0;
4016 ext_inode_hdr(inode)->eh_max =
4017 cpu_to_le16(ext4_ext_space_root(
4020 err = ext4_ext_dirty(
4021 handle, inode, path);
4029 if ((sbi->s_cluster_ratio > 1) &&
4030 ext4_find_delalloc_cluster(inode, map->m_lblk, 0))
4031 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4034 * requested block isn't allocated yet;
4035 * we couldn't try to create block if create flag is zero
4037 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
4039 * put just found gap into cache to speed up
4040 * subsequent requests
4042 ext4_ext_put_gap_in_cache(inode, path, map->m_lblk);
4047 * Okay, we need to do block allocation.
4049 map->m_flags &= ~EXT4_MAP_FROM_CLUSTER;
4050 newex.ee_block = cpu_to_le32(map->m_lblk);
4051 cluster_offset = map->m_lblk & (sbi->s_cluster_ratio-1);
4054 * If we are doing bigalloc, check to see if the extent returned
4055 * by ext4_ext_find_extent() implies a cluster we can use.
4057 if (cluster_offset && ex &&
4058 get_implied_cluster_alloc(inode->i_sb, map, ex, path)) {
4059 ar.len = allocated = map->m_len;
4060 newblock = map->m_pblk;
4061 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4062 goto got_allocated_blocks;
4065 /* find neighbour allocated blocks */
4066 ar.lleft = map->m_lblk;
4067 err = ext4_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
4070 ar.lright = map->m_lblk;
4072 err = ext4_ext_search_right(inode, path, &ar.lright, &ar.pright, &ex2);
4076 /* Check if the extent after searching to the right implies a
4077 * cluster we can use. */
4078 if ((sbi->s_cluster_ratio > 1) && ex2 &&
4079 get_implied_cluster_alloc(inode->i_sb, map, ex2, path)) {
4080 ar.len = allocated = map->m_len;
4081 newblock = map->m_pblk;
4082 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4083 goto got_allocated_blocks;
4087 * See if request is beyond maximum number of blocks we can have in
4088 * a single extent. For an initialized extent this limit is
4089 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
4090 * EXT_UNINIT_MAX_LEN.
4092 if (map->m_len > EXT_INIT_MAX_LEN &&
4093 !(flags & EXT4_GET_BLOCKS_UNINIT_EXT))
4094 map->m_len = EXT_INIT_MAX_LEN;
4095 else if (map->m_len > EXT_UNINIT_MAX_LEN &&
4096 (flags & EXT4_GET_BLOCKS_UNINIT_EXT))
4097 map->m_len = EXT_UNINIT_MAX_LEN;
4099 /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
4100 newex.ee_len = cpu_to_le16(map->m_len);
4101 err = ext4_ext_check_overlap(sbi, inode, &newex, path);
4103 allocated = ext4_ext_get_actual_len(&newex);
4105 allocated = map->m_len;
4107 /* allocate new block */
4109 ar.goal = ext4_ext_find_goal(inode, path, map->m_lblk);
4110 ar.logical = map->m_lblk;
4112 * We calculate the offset from the beginning of the cluster
4113 * for the logical block number, since when we allocate a
4114 * physical cluster, the physical block should start at the
4115 * same offset from the beginning of the cluster. This is
4116 * needed so that future calls to get_implied_cluster_alloc()
4119 offset = map->m_lblk & (sbi->s_cluster_ratio - 1);
4120 ar.len = EXT4_NUM_B2C(sbi, offset+allocated);
4122 ar.logical -= offset;
4123 if (S_ISREG(inode->i_mode))
4124 ar.flags = EXT4_MB_HINT_DATA;
4126 /* disable in-core preallocation for non-regular files */
4128 if (flags & EXT4_GET_BLOCKS_NO_NORMALIZE)
4129 ar.flags |= EXT4_MB_HINT_NOPREALLOC;
4130 newblock = ext4_mb_new_blocks(handle, &ar, &err);
4133 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
4134 ar.goal, newblock, allocated);
4136 allocated_clusters = ar.len;
4137 ar.len = EXT4_C2B(sbi, ar.len) - offset;
4138 if (ar.len > allocated)
4141 got_allocated_blocks:
4142 /* try to insert new extent into found leaf and return */
4143 ext4_ext_store_pblock(&newex, newblock + offset);
4144 newex.ee_len = cpu_to_le16(ar.len);
4145 /* Mark uninitialized */
4146 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){
4147 ext4_ext_mark_uninitialized(&newex);
4149 * io_end structure was created for every IO write to an
4150 * uninitialized extent. To avoid unnecessary conversion,
4151 * here we flag the IO that really needs the conversion.
4152 * For non asycn direct IO case, flag the inode state
4153 * that we need to perform conversion when IO is done.
4155 if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
4157 ext4_set_io_unwritten_flag(inode, io);
4159 ext4_set_inode_state(inode,
4160 EXT4_STATE_DIO_UNWRITTEN);
4162 if (ext4_should_dioread_nolock(inode))
4163 map->m_flags |= EXT4_MAP_UNINIT;
4167 if ((flags & EXT4_GET_BLOCKS_KEEP_SIZE) == 0)
4168 err = check_eofblocks_fl(handle, inode, map->m_lblk,
4171 err = ext4_ext_insert_extent(handle, inode, path,
4173 if (err && free_on_err) {
4174 int fb_flags = flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE ?
4175 EXT4_FREE_BLOCKS_NO_QUOT_UPDATE : 0;
4176 /* free data blocks we just allocated */
4177 /* not a good idea to call discard here directly,
4178 * but otherwise we'd need to call it every free() */
4179 ext4_discard_preallocations(inode);
4180 ext4_free_blocks(handle, inode, NULL, ext4_ext_pblock(&newex),
4181 ext4_ext_get_actual_len(&newex), fb_flags);
4185 /* previous routine could use block we allocated */
4186 newblock = ext4_ext_pblock(&newex);
4187 allocated = ext4_ext_get_actual_len(&newex);
4188 if (allocated > map->m_len)
4189 allocated = map->m_len;
4190 map->m_flags |= EXT4_MAP_NEW;
4193 * Update reserved blocks/metadata blocks after successful
4194 * block allocation which had been deferred till now.
4196 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
4197 unsigned int reserved_clusters;
4199 * Check how many clusters we had reserved this allocated range
4201 reserved_clusters = get_reserved_cluster_alloc(inode,
4202 map->m_lblk, allocated);
4203 if (map->m_flags & EXT4_MAP_FROM_CLUSTER) {
4204 if (reserved_clusters) {
4206 * We have clusters reserved for this range.
4207 * But since we are not doing actual allocation
4208 * and are simply using blocks from previously
4209 * allocated cluster, we should release the
4210 * reservation and not claim quota.
4212 ext4_da_update_reserve_space(inode,
4213 reserved_clusters, 0);
4216 BUG_ON(allocated_clusters < reserved_clusters);
4217 /* We will claim quota for all newly allocated blocks.*/
4218 ext4_da_update_reserve_space(inode, allocated_clusters,
4220 if (reserved_clusters < allocated_clusters) {
4221 struct ext4_inode_info *ei = EXT4_I(inode);
4222 int reservation = allocated_clusters -
4225 * It seems we claimed few clusters outside of
4226 * the range of this allocation. We should give
4227 * it back to the reservation pool. This can
4228 * happen in the following case:
4230 * * Suppose s_cluster_ratio is 4 (i.e., each
4231 * cluster has 4 blocks. Thus, the clusters
4232 * are [0-3],[4-7],[8-11]...
4233 * * First comes delayed allocation write for
4234 * logical blocks 10 & 11. Since there were no
4235 * previous delayed allocated blocks in the
4236 * range [8-11], we would reserve 1 cluster
4238 * * Next comes write for logical blocks 3 to 8.
4239 * In this case, we will reserve 2 clusters
4240 * (for [0-3] and [4-7]; and not for [8-11] as
4241 * that range has a delayed allocated blocks.
4242 * Thus total reserved clusters now becomes 3.
4243 * * Now, during the delayed allocation writeout
4244 * time, we will first write blocks [3-8] and
4245 * allocate 3 clusters for writing these
4246 * blocks. Also, we would claim all these
4247 * three clusters above.
4248 * * Now when we come here to writeout the
4249 * blocks [10-11], we would expect to claim
4250 * the reservation of 1 cluster we had made
4251 * (and we would claim it since there are no
4252 * more delayed allocated blocks in the range
4253 * [8-11]. But our reserved cluster count had
4254 * already gone to 0.
4256 * Thus, at the step 4 above when we determine
4257 * that there are still some unwritten delayed
4258 * allocated blocks outside of our current
4259 * block range, we should increment the
4260 * reserved clusters count so that when the
4261 * remaining blocks finally gets written, we
4264 dquot_reserve_block(inode,
4265 EXT4_C2B(sbi, reservation));
4266 spin_lock(&ei->i_block_reservation_lock);
4267 ei->i_reserved_data_blocks += reservation;
4268 spin_unlock(&ei->i_block_reservation_lock);
4274 * Cache the extent and update transaction to commit on fdatasync only
4275 * when it is _not_ an uninitialized extent.
4277 if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0) {
4278 ext4_ext_put_in_cache(inode, map->m_lblk, allocated, newblock);
4279 ext4_update_inode_fsync_trans(handle, inode, 1);
4281 ext4_update_inode_fsync_trans(handle, inode, 0);
4283 if (allocated > map->m_len)
4284 allocated = map->m_len;
4285 ext4_ext_show_leaf(inode, path);
4286 map->m_flags |= EXT4_MAP_MAPPED;
4287 map->m_pblk = newblock;
4288 map->m_len = allocated;
4291 ext4_ext_drop_refs(path);
4294 result = (flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) ?
4295 punched_out : allocated;
4297 trace_ext4_ext_map_blocks_exit(inode, map->m_lblk,
4298 newblock, map->m_len, err ? err : result);
4300 return err ? err : result;
4303 void ext4_ext_truncate(struct inode *inode)
4305 struct address_space *mapping = inode->i_mapping;
4306 struct super_block *sb = inode->i_sb;
4307 ext4_lblk_t last_block;
4313 * finish any pending end_io work so we won't run the risk of
4314 * converting any truncated blocks to initialized later
4316 ext4_flush_completed_IO(inode);
4319 * probably first extent we're gonna free will be last in block
4321 err = ext4_writepage_trans_blocks(inode);
4322 handle = ext4_journal_start(inode, err);
4326 if (inode->i_size % PAGE_CACHE_SIZE != 0) {
4327 page_len = PAGE_CACHE_SIZE -
4328 (inode->i_size & (PAGE_CACHE_SIZE - 1));
4330 err = ext4_discard_partial_page_buffers(handle,
4331 mapping, inode->i_size, page_len, 0);
4337 if (ext4_orphan_add(handle, inode))
4340 down_write(&EXT4_I(inode)->i_data_sem);
4341 ext4_ext_invalidate_cache(inode);
4343 ext4_discard_preallocations(inode);
4346 * TODO: optimization is possible here.
4347 * Probably we need not scan at all,
4348 * because page truncation is enough.
4351 /* we have to know where to truncate from in crash case */
4352 EXT4_I(inode)->i_disksize = inode->i_size;
4353 ext4_mark_inode_dirty(handle, inode);
4355 last_block = (inode->i_size + sb->s_blocksize - 1)
4356 >> EXT4_BLOCK_SIZE_BITS(sb);
4357 err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
4359 /* In a multi-transaction truncate, we only make the final
4360 * transaction synchronous.
4363 ext4_handle_sync(handle);
4365 up_write(&EXT4_I(inode)->i_data_sem);
4369 * If this was a simple ftruncate() and the file will remain alive,
4370 * then we need to clear up the orphan record which we created above.
4371 * However, if this was a real unlink then we were called by
4372 * ext4_delete_inode(), and we allow that function to clean up the
4373 * orphan info for us.
4376 ext4_orphan_del(handle, inode);
4378 inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
4379 ext4_mark_inode_dirty(handle, inode);
4380 ext4_journal_stop(handle);
4383 static void ext4_falloc_update_inode(struct inode *inode,
4384 int mode, loff_t new_size, int update_ctime)
4386 struct timespec now;
4389 now = current_fs_time(inode->i_sb);
4390 if (!timespec_equal(&inode->i_ctime, &now))
4391 inode->i_ctime = now;
4394 * Update only when preallocation was requested beyond
4397 if (!(mode & FALLOC_FL_KEEP_SIZE)) {
4398 if (new_size > i_size_read(inode))
4399 i_size_write(inode, new_size);
4400 if (new_size > EXT4_I(inode)->i_disksize)
4401 ext4_update_i_disksize(inode, new_size);
4404 * Mark that we allocate beyond EOF so the subsequent truncate
4405 * can proceed even if the new size is the same as i_size.
4407 if (new_size > i_size_read(inode))
4408 ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
4414 * preallocate space for a file. This implements ext4's fallocate file
4415 * operation, which gets called from sys_fallocate system call.
4416 * For block-mapped files, posix_fallocate should fall back to the method
4417 * of writing zeroes to the required new blocks (the same behavior which is
4418 * expected for file systems which do not support fallocate() system call).
4420 long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
4422 struct inode *inode = file->f_path.dentry->d_inode;
4425 unsigned int max_blocks;
4430 struct ext4_map_blocks map;
4431 unsigned int credits, blkbits = inode->i_blkbits;
4434 * currently supporting (pre)allocate mode for extent-based
4437 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
4440 /* Return error if mode is not supported */
4441 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
4444 if (mode & FALLOC_FL_PUNCH_HOLE)
4445 return ext4_punch_hole(file, offset, len);
4447 trace_ext4_fallocate_enter(inode, offset, len, mode);
4448 map.m_lblk = offset >> blkbits;
4450 * We can't just convert len to max_blocks because
4451 * If blocksize = 4096 offset = 3072 and len = 2048
4453 max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
4456 * credits to insert 1 extent into extent tree
4458 credits = ext4_chunk_trans_blocks(inode, max_blocks);
4459 mutex_lock(&inode->i_mutex);
4460 ret = inode_newsize_ok(inode, (len + offset));
4462 mutex_unlock(&inode->i_mutex);
4463 trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
4466 flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT;
4467 if (mode & FALLOC_FL_KEEP_SIZE)
4468 flags |= EXT4_GET_BLOCKS_KEEP_SIZE;
4470 * Don't normalize the request if it can fit in one extent so
4471 * that it doesn't get unnecessarily split into multiple
4474 if (len <= EXT_UNINIT_MAX_LEN << blkbits)
4475 flags |= EXT4_GET_BLOCKS_NO_NORMALIZE;
4477 while (ret >= 0 && ret < max_blocks) {
4478 map.m_lblk = map.m_lblk + ret;
4479 map.m_len = max_blocks = max_blocks - ret;
4480 handle = ext4_journal_start(inode, credits);
4481 if (IS_ERR(handle)) {
4482 ret = PTR_ERR(handle);
4485 ret = ext4_map_blocks(handle, inode, &map, flags);
4489 printk(KERN_ERR "%s: ext4_ext_map_blocks "
4490 "returned error inode#%lu, block=%u, "
4491 "max_blocks=%u", __func__,
4492 inode->i_ino, map.m_lblk, max_blocks);
4494 ext4_mark_inode_dirty(handle, inode);
4495 ret2 = ext4_journal_stop(handle);
4498 if ((map.m_lblk + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
4499 blkbits) >> blkbits))
4500 new_size = offset + len;
4502 new_size = ((loff_t) map.m_lblk + ret) << blkbits;
4504 ext4_falloc_update_inode(inode, mode, new_size,
4505 (map.m_flags & EXT4_MAP_NEW));
4506 ext4_mark_inode_dirty(handle, inode);
4507 ret2 = ext4_journal_stop(handle);
4511 if (ret == -ENOSPC &&
4512 ext4_should_retry_alloc(inode->i_sb, &retries)) {
4516 mutex_unlock(&inode->i_mutex);
4517 trace_ext4_fallocate_exit(inode, offset, max_blocks,
4518 ret > 0 ? ret2 : ret);
4519 return ret > 0 ? ret2 : ret;
4523 * This function convert a range of blocks to written extents
4524 * The caller of this function will pass the start offset and the size.
4525 * all unwritten extents within this range will be converted to
4528 * This function is called from the direct IO end io call back
4529 * function, to convert the fallocated extents after IO is completed.
4530 * Returns 0 on success.
4532 int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
4536 unsigned int max_blocks;
4539 struct ext4_map_blocks map;
4540 unsigned int credits, blkbits = inode->i_blkbits;
4542 map.m_lblk = offset >> blkbits;
4544 * We can't just convert len to max_blocks because
4545 * If blocksize = 4096 offset = 3072 and len = 2048
4547 max_blocks = ((EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) -
4550 * credits to insert 1 extent into extent tree
4552 credits = ext4_chunk_trans_blocks(inode, max_blocks);
4553 while (ret >= 0 && ret < max_blocks) {
4555 map.m_len = (max_blocks -= ret);
4556 handle = ext4_journal_start(inode, credits);
4557 if (IS_ERR(handle)) {
4558 ret = PTR_ERR(handle);
4561 ret = ext4_map_blocks(handle, inode, &map,
4562 EXT4_GET_BLOCKS_IO_CONVERT_EXT);
4565 printk(KERN_ERR "%s: ext4_ext_map_blocks "
4566 "returned error inode#%lu, block=%u, "
4567 "max_blocks=%u", __func__,
4568 inode->i_ino, map.m_lblk, map.m_len);
4570 ext4_mark_inode_dirty(handle, inode);
4571 ret2 = ext4_journal_stop(handle);
4572 if (ret <= 0 || ret2 )
4575 return ret > 0 ? ret2 : ret;
4579 * Callback function called for each extent to gather FIEMAP information.
4581 static int ext4_ext_fiemap_cb(struct inode *inode, ext4_lblk_t next,
4582 struct ext4_ext_cache *newex, struct ext4_extent *ex,
4590 struct fiemap_extent_info *fieinfo = data;
4591 unsigned char blksize_bits;
4593 blksize_bits = inode->i_sb->s_blocksize_bits;
4594 logical = (__u64)newex->ec_block << blksize_bits;
4596 if (newex->ec_start == 0) {
4598 * No extent in extent-tree contains block @newex->ec_start,
4599 * then the block may stay in 1)a hole or 2)delayed-extent.
4601 * Holes or delayed-extents are processed as follows.
4602 * 1. lookup dirty pages with specified range in pagecache.
4603 * If no page is got, then there is no delayed-extent and
4604 * return with EXT_CONTINUE.
4605 * 2. find the 1st mapped buffer,
4606 * 3. check if the mapped buffer is both in the request range
4607 * and a delayed buffer. If not, there is no delayed-extent,
4609 * 4. a delayed-extent is found, the extent will be collected.
4611 ext4_lblk_t end = 0;
4612 pgoff_t last_offset;
4615 pgoff_t start_index = 0;
4616 struct page **pages = NULL;
4617 struct buffer_head *bh = NULL;
4618 struct buffer_head *head = NULL;
4619 unsigned int nr_pages = PAGE_SIZE / sizeof(struct page *);
4621 pages = kmalloc(PAGE_SIZE, GFP_KERNEL);
4625 offset = logical >> PAGE_SHIFT;
4627 last_offset = offset;
4629 ret = find_get_pages_tag(inode->i_mapping, &offset,
4630 PAGECACHE_TAG_DIRTY, nr_pages, pages);
4632 if (!(flags & FIEMAP_EXTENT_DELALLOC)) {
4633 /* First time, try to find a mapped buffer. */
4636 for (index = 0; index < ret; index++)
4637 page_cache_release(pages[index]);
4640 return EXT_CONTINUE;
4645 /* Try to find the 1st mapped buffer. */
4646 end = ((__u64)pages[index]->index << PAGE_SHIFT) >>
4648 if (!page_has_buffers(pages[index]))
4650 head = page_buffers(pages[index]);
4657 if (end >= newex->ec_block +
4659 /* The buffer is out of
4660 * the request range.
4664 if (buffer_mapped(bh) &&
4665 end >= newex->ec_block) {
4666 start_index = index - 1;
4667 /* get the 1st mapped buffer. */
4668 goto found_mapped_buffer;
4671 bh = bh->b_this_page;
4673 } while (bh != head);
4675 /* No mapped buffer in the range found in this page,
4676 * We need to look up next page.
4679 /* There is no page left, but we need to limit
4682 newex->ec_len = end - newex->ec_block;
4687 /*Find contiguous delayed buffers. */
4688 if (ret > 0 && pages[0]->index == last_offset)
4689 head = page_buffers(pages[0]);
4695 found_mapped_buffer:
4696 if (bh != NULL && buffer_delay(bh)) {
4697 /* 1st or contiguous delayed buffer found. */
4698 if (!(flags & FIEMAP_EXTENT_DELALLOC)) {
4700 * 1st delayed buffer found, record
4701 * the start of extent.
4703 flags |= FIEMAP_EXTENT_DELALLOC;
4704 newex->ec_block = end;
4705 logical = (__u64)end << blksize_bits;
4707 /* Find contiguous delayed buffers. */
4709 if (!buffer_delay(bh))
4710 goto found_delayed_extent;
4711 bh = bh->b_this_page;
4713 } while (bh != head);
4715 for (; index < ret; index++) {
4716 if (!page_has_buffers(pages[index])) {
4720 head = page_buffers(pages[index]);
4726 if (pages[index]->index !=
4727 pages[start_index]->index + index
4729 /* Blocks are not contiguous. */
4735 if (!buffer_delay(bh))
4736 /* Delayed-extent ends. */
4737 goto found_delayed_extent;
4738 bh = bh->b_this_page;
4740 } while (bh != head);
4742 } else if (!(flags & FIEMAP_EXTENT_DELALLOC))
4746 found_delayed_extent:
4747 newex->ec_len = min(end - newex->ec_block,
4748 (ext4_lblk_t)EXT_INIT_MAX_LEN);
4749 if (ret == nr_pages && bh != NULL &&
4750 newex->ec_len < EXT_INIT_MAX_LEN &&
4752 /* Have not collected an extent and continue. */
4753 for (index = 0; index < ret; index++)
4754 page_cache_release(pages[index]);
4758 for (index = 0; index < ret; index++)
4759 page_cache_release(pages[index]);
4763 physical = (__u64)newex->ec_start << blksize_bits;
4764 length = (__u64)newex->ec_len << blksize_bits;
4766 if (ex && ext4_ext_is_uninitialized(ex))
4767 flags |= FIEMAP_EXTENT_UNWRITTEN;
4769 if (next == EXT_MAX_BLOCKS)
4770 flags |= FIEMAP_EXTENT_LAST;
4772 ret = fiemap_fill_next_extent(fieinfo, logical, physical,
4778 return EXT_CONTINUE;
4780 /* fiemap flags we can handle specified here */
4781 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
4783 static int ext4_xattr_fiemap(struct inode *inode,
4784 struct fiemap_extent_info *fieinfo)
4788 __u32 flags = FIEMAP_EXTENT_LAST;
4789 int blockbits = inode->i_sb->s_blocksize_bits;
4793 if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
4794 struct ext4_iloc iloc;
4795 int offset; /* offset of xattr in inode */
4797 error = ext4_get_inode_loc(inode, &iloc);
4800 physical = iloc.bh->b_blocknr << blockbits;
4801 offset = EXT4_GOOD_OLD_INODE_SIZE +
4802 EXT4_I(inode)->i_extra_isize;
4804 length = EXT4_SB(inode->i_sb)->s_inode_size - offset;
4805 flags |= FIEMAP_EXTENT_DATA_INLINE;
4807 } else { /* external block */
4808 physical = EXT4_I(inode)->i_file_acl << blockbits;
4809 length = inode->i_sb->s_blocksize;
4813 error = fiemap_fill_next_extent(fieinfo, 0, physical,
4815 return (error < 0 ? error : 0);
4819 * ext4_ext_punch_hole
4821 * Punches a hole of "length" bytes in a file starting
4824 * @inode: The inode of the file to punch a hole in
4825 * @offset: The starting byte offset of the hole
4826 * @length: The length of the hole
4828 * Returns the number of blocks removed or negative on err
4830 int ext4_ext_punch_hole(struct file *file, loff_t offset, loff_t length)
4832 struct inode *inode = file->f_path.dentry->d_inode;
4833 struct super_block *sb = inode->i_sb;
4834 ext4_lblk_t first_block, stop_block;
4835 struct address_space *mapping = inode->i_mapping;
4837 loff_t first_page, last_page, page_len;
4838 loff_t first_page_offset, last_page_offset;
4839 int credits, err = 0;
4841 /* No need to punch hole beyond i_size */
4842 if (offset >= inode->i_size)
4846 * If the hole extends beyond i_size, set the hole
4847 * to end after the page that contains i_size
4849 if (offset + length > inode->i_size) {
4850 length = inode->i_size +
4851 PAGE_CACHE_SIZE - (inode->i_size & (PAGE_CACHE_SIZE - 1)) -
4855 first_page = (offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
4856 last_page = (offset + length) >> PAGE_CACHE_SHIFT;
4858 first_page_offset = first_page << PAGE_CACHE_SHIFT;
4859 last_page_offset = last_page << PAGE_CACHE_SHIFT;
4862 * Write out all dirty pages to avoid race conditions
4863 * Then release them.
4865 if (mapping->nrpages && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
4866 err = filemap_write_and_wait_range(mapping,
4867 offset, offset + length - 1);
4873 /* Now release the pages */
4874 if (last_page_offset > first_page_offset) {
4875 truncate_inode_pages_range(mapping, first_page_offset,
4876 last_page_offset-1);
4879 /* finish any pending end_io work */
4880 ext4_flush_completed_IO(inode);
4882 credits = ext4_writepage_trans_blocks(inode);
4883 handle = ext4_journal_start(inode, credits);
4885 return PTR_ERR(handle);
4887 err = ext4_orphan_add(handle, inode);
4892 * Now we need to zero out the non-page-aligned data in the
4893 * pages at the start and tail of the hole, and unmap the buffer
4894 * heads for the block aligned regions of the page that were
4895 * completely zeroed.
4897 if (first_page > last_page) {
4899 * If the file space being truncated is contained within a page
4900 * just zero out and unmap the middle of that page
4902 err = ext4_discard_partial_page_buffers(handle,
4903 mapping, offset, length, 0);
4909 * zero out and unmap the partial page that contains
4910 * the start of the hole
4912 page_len = first_page_offset - offset;
4914 err = ext4_discard_partial_page_buffers(handle, mapping,
4915 offset, page_len, 0);
4921 * zero out and unmap the partial page that contains
4922 * the end of the hole
4924 page_len = offset + length - last_page_offset;
4926 err = ext4_discard_partial_page_buffers(handle, mapping,
4927 last_page_offset, page_len, 0);
4934 * If i_size is contained in the last page, we need to
4935 * unmap and zero the partial page after i_size
4937 if (inode->i_size >> PAGE_CACHE_SHIFT == last_page &&
4938 inode->i_size % PAGE_CACHE_SIZE != 0) {
4940 page_len = PAGE_CACHE_SIZE -
4941 (inode->i_size & (PAGE_CACHE_SIZE - 1));
4944 err = ext4_discard_partial_page_buffers(handle,
4945 mapping, inode->i_size, page_len, 0);
4952 first_block = (offset + sb->s_blocksize - 1) >>
4953 EXT4_BLOCK_SIZE_BITS(sb);
4954 stop_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb);
4956 /* If there are no blocks to remove, return now */
4957 if (first_block >= stop_block)
4960 down_write(&EXT4_I(inode)->i_data_sem);
4961 ext4_ext_invalidate_cache(inode);
4962 ext4_discard_preallocations(inode);
4964 err = ext4_ext_remove_space(inode, first_block, stop_block - 1);
4966 ext4_ext_invalidate_cache(inode);
4967 ext4_discard_preallocations(inode);
4970 ext4_handle_sync(handle);
4972 up_write(&EXT4_I(inode)->i_data_sem);
4975 ext4_orphan_del(handle, inode);
4976 inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
4977 ext4_mark_inode_dirty(handle, inode);
4978 ext4_journal_stop(handle);
4981 int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
4982 __u64 start, __u64 len)
4984 ext4_lblk_t start_blk;
4987 /* fallback to generic here if not in extents fmt */
4988 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
4989 return generic_block_fiemap(inode, fieinfo, start, len,
4992 if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
4995 if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
4996 error = ext4_xattr_fiemap(inode, fieinfo);
4998 ext4_lblk_t len_blks;
5001 start_blk = start >> inode->i_sb->s_blocksize_bits;
5002 last_blk = (start + len - 1) >> inode->i_sb->s_blocksize_bits;
5003 if (last_blk >= EXT_MAX_BLOCKS)
5004 last_blk = EXT_MAX_BLOCKS-1;
5005 len_blks = ((ext4_lblk_t) last_blk) - start_blk + 1;
5008 * Walk the extent tree gathering extent information.
5009 * ext4_ext_fiemap_cb will push extents back to user.
5011 error = ext4_ext_walk_space(inode, start_blk, len_blks,
5012 ext4_ext_fiemap_cb, fieinfo);