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"
45 #include "ext4_extents.h"
50 * combine low and high parts of physical block number into ext4_fsblk_t
52 ext4_fsblk_t ext_pblock(struct ext4_extent *ex)
56 block = le32_to_cpu(ex->ee_start_lo);
57 block |= ((ext4_fsblk_t) le16_to_cpu(ex->ee_start_hi) << 31) << 1;
63 * combine low and high parts of a leaf physical block number into ext4_fsblk_t
65 ext4_fsblk_t idx_pblock(struct ext4_extent_idx *ix)
69 block = le32_to_cpu(ix->ei_leaf_lo);
70 block |= ((ext4_fsblk_t) le16_to_cpu(ix->ei_leaf_hi) << 31) << 1;
75 * ext4_ext_store_pblock:
76 * stores a large physical block number into an extent struct,
77 * breaking it into parts
79 void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb)
81 ex->ee_start_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));
82 ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
86 * ext4_idx_store_pblock:
87 * stores a large physical block number into an index struct,
88 * breaking it into parts
90 static void ext4_idx_store_pblock(struct ext4_extent_idx *ix, ext4_fsblk_t pb)
92 ix->ei_leaf_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));
93 ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
96 static int ext4_ext_truncate_extend_restart(handle_t *handle,
102 if (!ext4_handle_valid(handle))
104 if (handle->h_buffer_credits > needed)
106 err = ext4_journal_extend(handle, needed);
109 err = ext4_truncate_restart_trans(handle, inode, needed);
111 * We have dropped i_data_sem so someone might have cached again
112 * an extent we are going to truncate.
114 ext4_ext_invalidate_cache(inode);
124 static int ext4_ext_get_access(handle_t *handle, struct inode *inode,
125 struct ext4_ext_path *path)
128 /* path points to block */
129 return ext4_journal_get_write_access(handle, path->p_bh);
131 /* path points to leaf/index in inode body */
132 /* we use in-core data, no need to protect them */
142 static int ext4_ext_dirty(handle_t *handle, struct inode *inode,
143 struct ext4_ext_path *path)
147 /* path points to block */
148 err = ext4_handle_dirty_metadata(handle, inode, path->p_bh);
150 /* path points to leaf/index in inode body */
151 err = ext4_mark_inode_dirty(handle, inode);
156 static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
157 struct ext4_ext_path *path,
160 struct ext4_inode_info *ei = EXT4_I(inode);
161 ext4_fsblk_t bg_start;
162 ext4_fsblk_t last_block;
163 ext4_grpblk_t colour;
164 ext4_group_t block_group;
165 int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));
169 struct ext4_extent *ex;
170 depth = path->p_depth;
172 /* try to predict block placement */
173 ex = path[depth].p_ext;
175 return ext_pblock(ex)+(block-le32_to_cpu(ex->ee_block));
177 /* it looks like index is empty;
178 * try to find starting block from index itself */
179 if (path[depth].p_bh)
180 return path[depth].p_bh->b_blocknr;
183 /* OK. use inode's group */
184 block_group = ei->i_block_group;
185 if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) {
187 * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
188 * block groups per flexgroup, reserve the first block
189 * group for directories and special files. Regular
190 * files will start at the second block group. This
191 * tends to speed up directory access and improves
194 block_group &= ~(flex_size-1);
195 if (S_ISREG(inode->i_mode))
198 bg_start = (block_group * EXT4_BLOCKS_PER_GROUP(inode->i_sb)) +
199 le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_first_data_block);
200 last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
203 * If we are doing delayed allocation, we don't need take
204 * colour into account.
206 if (test_opt(inode->i_sb, DELALLOC))
209 if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
210 colour = (current->pid % 16) *
211 (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
213 colour = (current->pid % 16) * ((last_block - bg_start) / 16);
214 return bg_start + colour + block;
218 * Allocation for a meta data block
221 ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,
222 struct ext4_ext_path *path,
223 struct ext4_extent *ex, int *err)
225 ext4_fsblk_t goal, newblock;
227 goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
228 newblock = ext4_new_meta_blocks(handle, inode, goal, NULL, err);
232 static inline int ext4_ext_space_block(struct inode *inode, int check)
236 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
237 / sizeof(struct ext4_extent);
239 #ifdef AGGRESSIVE_TEST
247 static inline int ext4_ext_space_block_idx(struct inode *inode, int check)
251 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
252 / sizeof(struct ext4_extent_idx);
254 #ifdef AGGRESSIVE_TEST
262 static inline int ext4_ext_space_root(struct inode *inode, int check)
266 size = sizeof(EXT4_I(inode)->i_data);
267 size -= sizeof(struct ext4_extent_header);
268 size /= sizeof(struct ext4_extent);
270 #ifdef AGGRESSIVE_TEST
278 static inline int ext4_ext_space_root_idx(struct inode *inode, int check)
282 size = sizeof(EXT4_I(inode)->i_data);
283 size -= sizeof(struct ext4_extent_header);
284 size /= sizeof(struct ext4_extent_idx);
286 #ifdef AGGRESSIVE_TEST
295 * Calculate the number of metadata blocks needed
296 * to allocate @blocks
297 * Worse case is one block per extent
299 int ext4_ext_calc_metadata_amount(struct inode *inode, int blocks)
301 int lcap, icap, rcap, leafs, idxs, num;
302 int newextents = blocks;
304 rcap = ext4_ext_space_root_idx(inode, 0);
305 lcap = ext4_ext_space_block(inode, 0);
306 icap = ext4_ext_space_block_idx(inode, 0);
308 /* number of new leaf blocks needed */
309 num = leafs = (newextents + lcap - 1) / lcap;
312 * Worse case, we need separate index block(s)
313 * to link all new leaf blocks
315 idxs = (leafs + icap - 1) / icap;
318 idxs = (idxs + icap - 1) / icap;
319 } while (idxs > rcap);
325 ext4_ext_max_entries(struct inode *inode, int depth)
329 if (depth == ext_depth(inode)) {
331 max = ext4_ext_space_root(inode, 1);
333 max = ext4_ext_space_root_idx(inode, 1);
336 max = ext4_ext_space_block(inode, 1);
338 max = ext4_ext_space_block_idx(inode, 1);
344 static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext)
346 ext4_fsblk_t block = ext_pblock(ext);
347 int len = ext4_ext_get_actual_len(ext);
349 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
352 static int ext4_valid_extent_idx(struct inode *inode,
353 struct ext4_extent_idx *ext_idx)
355 ext4_fsblk_t block = idx_pblock(ext_idx);
357 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, 1);
360 static int ext4_valid_extent_entries(struct inode *inode,
361 struct ext4_extent_header *eh,
364 struct ext4_extent *ext;
365 struct ext4_extent_idx *ext_idx;
366 unsigned short entries;
367 if (eh->eh_entries == 0)
370 entries = le16_to_cpu(eh->eh_entries);
374 ext = EXT_FIRST_EXTENT(eh);
376 if (!ext4_valid_extent(inode, ext))
382 ext_idx = EXT_FIRST_INDEX(eh);
384 if (!ext4_valid_extent_idx(inode, ext_idx))
393 static int __ext4_ext_check(const char *function, struct inode *inode,
394 struct ext4_extent_header *eh,
397 const char *error_msg;
400 if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
401 error_msg = "invalid magic";
404 if (unlikely(le16_to_cpu(eh->eh_depth) != depth)) {
405 error_msg = "unexpected eh_depth";
408 if (unlikely(eh->eh_max == 0)) {
409 error_msg = "invalid eh_max";
412 max = ext4_ext_max_entries(inode, depth);
413 if (unlikely(le16_to_cpu(eh->eh_max) > max)) {
414 error_msg = "too large eh_max";
417 if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
418 error_msg = "invalid eh_entries";
421 if (!ext4_valid_extent_entries(inode, eh, depth)) {
422 error_msg = "invalid extent entries";
428 ext4_error(inode->i_sb, function,
429 "bad header/extent in inode #%lu: %s - magic %x, "
430 "entries %u, max %u(%u), depth %u(%u)",
431 inode->i_ino, error_msg, le16_to_cpu(eh->eh_magic),
432 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
433 max, le16_to_cpu(eh->eh_depth), depth);
438 #define ext4_ext_check(inode, eh, depth) \
439 __ext4_ext_check(__func__, inode, eh, depth)
441 int ext4_ext_check_inode(struct inode *inode)
443 return ext4_ext_check(inode, ext_inode_hdr(inode), ext_depth(inode));
447 static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
449 int k, l = path->p_depth;
452 for (k = 0; k <= l; k++, path++) {
454 ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
455 idx_pblock(path->p_idx));
456 } else if (path->p_ext) {
457 ext_debug(" %d:[%d]%d:%llu ",
458 le32_to_cpu(path->p_ext->ee_block),
459 ext4_ext_is_uninitialized(path->p_ext),
460 ext4_ext_get_actual_len(path->p_ext),
461 ext_pblock(path->p_ext));
468 static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
470 int depth = ext_depth(inode);
471 struct ext4_extent_header *eh;
472 struct ext4_extent *ex;
478 eh = path[depth].p_hdr;
479 ex = EXT_FIRST_EXTENT(eh);
481 ext_debug("Displaying leaf extents for inode %lu\n", inode->i_ino);
483 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
484 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block),
485 ext4_ext_is_uninitialized(ex),
486 ext4_ext_get_actual_len(ex), ext_pblock(ex));
491 #define ext4_ext_show_path(inode, path)
492 #define ext4_ext_show_leaf(inode, path)
495 void ext4_ext_drop_refs(struct ext4_ext_path *path)
497 int depth = path->p_depth;
500 for (i = 0; i <= depth; i++, path++)
508 * ext4_ext_binsearch_idx:
509 * binary search for the closest index of the given block
510 * the header must be checked before calling this
513 ext4_ext_binsearch_idx(struct inode *inode,
514 struct ext4_ext_path *path, ext4_lblk_t block)
516 struct ext4_extent_header *eh = path->p_hdr;
517 struct ext4_extent_idx *r, *l, *m;
520 ext_debug("binsearch for %u(idx): ", block);
522 l = EXT_FIRST_INDEX(eh) + 1;
523 r = EXT_LAST_INDEX(eh);
526 if (block < le32_to_cpu(m->ei_block))
530 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block),
531 m, le32_to_cpu(m->ei_block),
532 r, le32_to_cpu(r->ei_block));
536 ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block),
537 idx_pblock(path->p_idx));
539 #ifdef CHECK_BINSEARCH
541 struct ext4_extent_idx *chix, *ix;
544 chix = ix = EXT_FIRST_INDEX(eh);
545 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
547 le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
548 printk(KERN_DEBUG "k=%d, ix=0x%p, "
550 ix, EXT_FIRST_INDEX(eh));
551 printk(KERN_DEBUG "%u <= %u\n",
552 le32_to_cpu(ix->ei_block),
553 le32_to_cpu(ix[-1].ei_block));
555 BUG_ON(k && le32_to_cpu(ix->ei_block)
556 <= le32_to_cpu(ix[-1].ei_block));
557 if (block < le32_to_cpu(ix->ei_block))
561 BUG_ON(chix != path->p_idx);
568 * ext4_ext_binsearch:
569 * binary search for closest extent of the given block
570 * the header must be checked before calling this
573 ext4_ext_binsearch(struct inode *inode,
574 struct ext4_ext_path *path, ext4_lblk_t block)
576 struct ext4_extent_header *eh = path->p_hdr;
577 struct ext4_extent *r, *l, *m;
579 if (eh->eh_entries == 0) {
581 * this leaf is empty:
582 * we get such a leaf in split/add case
587 ext_debug("binsearch for %u: ", block);
589 l = EXT_FIRST_EXTENT(eh) + 1;
590 r = EXT_LAST_EXTENT(eh);
594 if (block < le32_to_cpu(m->ee_block))
598 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block),
599 m, le32_to_cpu(m->ee_block),
600 r, le32_to_cpu(r->ee_block));
604 ext_debug(" -> %d:%llu:[%d]%d ",
605 le32_to_cpu(path->p_ext->ee_block),
606 ext_pblock(path->p_ext),
607 ext4_ext_is_uninitialized(path->p_ext),
608 ext4_ext_get_actual_len(path->p_ext));
610 #ifdef CHECK_BINSEARCH
612 struct ext4_extent *chex, *ex;
615 chex = ex = EXT_FIRST_EXTENT(eh);
616 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
617 BUG_ON(k && le32_to_cpu(ex->ee_block)
618 <= le32_to_cpu(ex[-1].ee_block));
619 if (block < le32_to_cpu(ex->ee_block))
623 BUG_ON(chex != path->p_ext);
629 int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
631 struct ext4_extent_header *eh;
633 eh = ext_inode_hdr(inode);
636 eh->eh_magic = EXT4_EXT_MAGIC;
637 eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode, 0));
638 ext4_mark_inode_dirty(handle, inode);
639 ext4_ext_invalidate_cache(inode);
643 struct ext4_ext_path *
644 ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
645 struct ext4_ext_path *path)
647 struct ext4_extent_header *eh;
648 struct buffer_head *bh;
649 short int depth, i, ppos = 0, alloc = 0;
651 eh = ext_inode_hdr(inode);
652 depth = ext_depth(inode);
654 /* account possible depth increase */
656 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 2),
659 return ERR_PTR(-ENOMEM);
666 /* walk through the tree */
668 int need_to_validate = 0;
670 ext_debug("depth %d: num %d, max %d\n",
671 ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
673 ext4_ext_binsearch_idx(inode, path + ppos, block);
674 path[ppos].p_block = idx_pblock(path[ppos].p_idx);
675 path[ppos].p_depth = i;
676 path[ppos].p_ext = NULL;
678 bh = sb_getblk(inode->i_sb, path[ppos].p_block);
681 if (!bh_uptodate_or_lock(bh)) {
682 if (bh_submit_read(bh) < 0) {
686 /* validate the extent entries */
687 need_to_validate = 1;
689 eh = ext_block_hdr(bh);
691 BUG_ON(ppos > depth);
692 path[ppos].p_bh = bh;
693 path[ppos].p_hdr = eh;
696 if (need_to_validate && ext4_ext_check(inode, eh, i))
700 path[ppos].p_depth = i;
701 path[ppos].p_ext = NULL;
702 path[ppos].p_idx = NULL;
705 ext4_ext_binsearch(inode, path + ppos, block);
706 /* if not an empty leaf */
707 if (path[ppos].p_ext)
708 path[ppos].p_block = ext_pblock(path[ppos].p_ext);
710 ext4_ext_show_path(inode, path);
715 ext4_ext_drop_refs(path);
718 return ERR_PTR(-EIO);
722 * ext4_ext_insert_index:
723 * insert new index [@logical;@ptr] into the block at @curp;
724 * check where to insert: before @curp or after @curp
726 static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
727 struct ext4_ext_path *curp,
728 int logical, ext4_fsblk_t ptr)
730 struct ext4_extent_idx *ix;
733 err = ext4_ext_get_access(handle, inode, curp);
737 BUG_ON(logical == le32_to_cpu(curp->p_idx->ei_block));
738 len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
739 if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
741 if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
742 len = (len - 1) * sizeof(struct ext4_extent_idx);
743 len = len < 0 ? 0 : len;
744 ext_debug("insert new index %d after: %llu. "
745 "move %d from 0x%p to 0x%p\n",
747 (curp->p_idx + 1), (curp->p_idx + 2));
748 memmove(curp->p_idx + 2, curp->p_idx + 1, len);
750 ix = curp->p_idx + 1;
753 len = len * sizeof(struct ext4_extent_idx);
754 len = len < 0 ? 0 : len;
755 ext_debug("insert new index %d before: %llu. "
756 "move %d from 0x%p to 0x%p\n",
758 curp->p_idx, (curp->p_idx + 1));
759 memmove(curp->p_idx + 1, curp->p_idx, len);
763 ix->ei_block = cpu_to_le32(logical);
764 ext4_idx_store_pblock(ix, ptr);
765 le16_add_cpu(&curp->p_hdr->eh_entries, 1);
767 BUG_ON(le16_to_cpu(curp->p_hdr->eh_entries)
768 > le16_to_cpu(curp->p_hdr->eh_max));
769 BUG_ON(ix > EXT_LAST_INDEX(curp->p_hdr));
771 err = ext4_ext_dirty(handle, inode, curp);
772 ext4_std_error(inode->i_sb, err);
779 * inserts new subtree into the path, using free index entry
781 * - allocates all needed blocks (new leaf and all intermediate index blocks)
782 * - makes decision where to split
783 * - moves remaining extents and index entries (right to the split point)
784 * into the newly allocated blocks
785 * - initializes subtree
787 static int ext4_ext_split(handle_t *handle, struct inode *inode,
788 struct ext4_ext_path *path,
789 struct ext4_extent *newext, int at)
791 struct buffer_head *bh = NULL;
792 int depth = ext_depth(inode);
793 struct ext4_extent_header *neh;
794 struct ext4_extent_idx *fidx;
795 struct ext4_extent *ex;
797 ext4_fsblk_t newblock, oldblock;
799 ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */
802 /* make decision: where to split? */
803 /* FIXME: now decision is simplest: at current extent */
805 /* if current leaf will be split, then we should use
806 * border from split point */
807 BUG_ON(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr));
808 if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
809 border = path[depth].p_ext[1].ee_block;
810 ext_debug("leaf will be split."
811 " next leaf starts at %d\n",
812 le32_to_cpu(border));
814 border = newext->ee_block;
815 ext_debug("leaf will be added."
816 " next leaf starts at %d\n",
817 le32_to_cpu(border));
821 * If error occurs, then we break processing
822 * and mark filesystem read-only. index won't
823 * be inserted and tree will be in consistent
824 * state. Next mount will repair buffers too.
828 * Get array to track all allocated blocks.
829 * We need this to handle errors and free blocks
832 ablocks = kzalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS);
836 /* allocate all needed blocks */
837 ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
838 for (a = 0; a < depth - at; a++) {
839 newblock = ext4_ext_new_meta_block(handle, inode, path,
843 ablocks[a] = newblock;
846 /* initialize new leaf */
847 newblock = ablocks[--a];
848 BUG_ON(newblock == 0);
849 bh = sb_getblk(inode->i_sb, newblock);
856 err = ext4_journal_get_create_access(handle, bh);
860 neh = ext_block_hdr(bh);
862 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
863 neh->eh_magic = EXT4_EXT_MAGIC;
865 ex = EXT_FIRST_EXTENT(neh);
867 /* move remainder of path[depth] to the new leaf */
868 BUG_ON(path[depth].p_hdr->eh_entries != path[depth].p_hdr->eh_max);
869 /* start copy from next extent */
870 /* TODO: we could do it by single memmove */
873 while (path[depth].p_ext <=
874 EXT_MAX_EXTENT(path[depth].p_hdr)) {
875 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
876 le32_to_cpu(path[depth].p_ext->ee_block),
877 ext_pblock(path[depth].p_ext),
878 ext4_ext_is_uninitialized(path[depth].p_ext),
879 ext4_ext_get_actual_len(path[depth].p_ext),
881 /*memmove(ex++, path[depth].p_ext++,
882 sizeof(struct ext4_extent));
888 memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m);
889 le16_add_cpu(&neh->eh_entries, m);
892 set_buffer_uptodate(bh);
895 err = ext4_handle_dirty_metadata(handle, inode, bh);
901 /* correct old leaf */
903 err = ext4_ext_get_access(handle, inode, path + depth);
906 le16_add_cpu(&path[depth].p_hdr->eh_entries, -m);
907 err = ext4_ext_dirty(handle, inode, path + depth);
913 /* create intermediate indexes */
917 ext_debug("create %d intermediate indices\n", k);
918 /* insert new index into current index block */
919 /* current depth stored in i var */
923 newblock = ablocks[--a];
924 bh = sb_getblk(inode->i_sb, newblock);
931 err = ext4_journal_get_create_access(handle, bh);
935 neh = ext_block_hdr(bh);
936 neh->eh_entries = cpu_to_le16(1);
937 neh->eh_magic = EXT4_EXT_MAGIC;
938 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
939 neh->eh_depth = cpu_to_le16(depth - i);
940 fidx = EXT_FIRST_INDEX(neh);
941 fidx->ei_block = border;
942 ext4_idx_store_pblock(fidx, oldblock);
944 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
945 i, newblock, le32_to_cpu(border), oldblock);
950 ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
951 EXT_MAX_INDEX(path[i].p_hdr));
952 BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) !=
953 EXT_LAST_INDEX(path[i].p_hdr));
954 while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
955 ext_debug("%d: move %d:%llu in new index %llu\n", i,
956 le32_to_cpu(path[i].p_idx->ei_block),
957 idx_pblock(path[i].p_idx),
959 /*memmove(++fidx, path[i].p_idx++,
960 sizeof(struct ext4_extent_idx));
962 BUG_ON(neh->eh_entries > neh->eh_max);*/
967 memmove(++fidx, path[i].p_idx - m,
968 sizeof(struct ext4_extent_idx) * m);
969 le16_add_cpu(&neh->eh_entries, m);
971 set_buffer_uptodate(bh);
974 err = ext4_handle_dirty_metadata(handle, inode, bh);
980 /* correct old index */
982 err = ext4_ext_get_access(handle, inode, path + i);
985 le16_add_cpu(&path[i].p_hdr->eh_entries, -m);
986 err = ext4_ext_dirty(handle, inode, path + i);
994 /* insert new index */
995 err = ext4_ext_insert_index(handle, inode, path + at,
996 le32_to_cpu(border), newblock);
1000 if (buffer_locked(bh))
1006 /* free all allocated blocks in error case */
1007 for (i = 0; i < depth; i++) {
1010 ext4_free_blocks(handle, inode, ablocks[i], 1, 1);
1019 * ext4_ext_grow_indepth:
1020 * implements tree growing procedure:
1021 * - allocates new block
1022 * - moves top-level data (index block or leaf) into the new block
1023 * - initializes new top-level, creating index that points to the
1024 * just created block
1026 static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
1027 struct ext4_ext_path *path,
1028 struct ext4_extent *newext)
1030 struct ext4_ext_path *curp = path;
1031 struct ext4_extent_header *neh;
1032 struct ext4_extent_idx *fidx;
1033 struct buffer_head *bh;
1034 ext4_fsblk_t newblock;
1037 newblock = ext4_ext_new_meta_block(handle, inode, path, newext, &err);
1041 bh = sb_getblk(inode->i_sb, newblock);
1044 ext4_std_error(inode->i_sb, err);
1049 err = ext4_journal_get_create_access(handle, bh);
1055 /* move top-level index/leaf into new block */
1056 memmove(bh->b_data, curp->p_hdr, sizeof(EXT4_I(inode)->i_data));
1058 /* set size of new block */
1059 neh = ext_block_hdr(bh);
1060 /* old root could have indexes or leaves
1061 * so calculate e_max right way */
1062 if (ext_depth(inode))
1063 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
1065 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
1066 neh->eh_magic = EXT4_EXT_MAGIC;
1067 set_buffer_uptodate(bh);
1070 err = ext4_handle_dirty_metadata(handle, inode, bh);
1074 /* create index in new top-level index: num,max,pointer */
1075 err = ext4_ext_get_access(handle, inode, curp);
1079 curp->p_hdr->eh_magic = EXT4_EXT_MAGIC;
1080 curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode, 0));
1081 curp->p_hdr->eh_entries = cpu_to_le16(1);
1082 curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
1084 if (path[0].p_hdr->eh_depth)
1085 curp->p_idx->ei_block =
1086 EXT_FIRST_INDEX(path[0].p_hdr)->ei_block;
1088 curp->p_idx->ei_block =
1089 EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
1090 ext4_idx_store_pblock(curp->p_idx, newblock);
1092 neh = ext_inode_hdr(inode);
1093 fidx = EXT_FIRST_INDEX(neh);
1094 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1095 le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
1096 le32_to_cpu(fidx->ei_block), idx_pblock(fidx));
1098 neh->eh_depth = cpu_to_le16(path->p_depth + 1);
1099 err = ext4_ext_dirty(handle, inode, curp);
1107 * ext4_ext_create_new_leaf:
1108 * finds empty index and adds new leaf.
1109 * if no free index is found, then it requests in-depth growing.
1111 static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
1112 struct ext4_ext_path *path,
1113 struct ext4_extent *newext)
1115 struct ext4_ext_path *curp;
1116 int depth, i, err = 0;
1119 i = depth = ext_depth(inode);
1121 /* walk up to the tree and look for free index entry */
1122 curp = path + depth;
1123 while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
1128 /* we use already allocated block for index block,
1129 * so subsequent data blocks should be contiguous */
1130 if (EXT_HAS_FREE_INDEX(curp)) {
1131 /* if we found index with free entry, then use that
1132 * entry: create all needed subtree and add new leaf */
1133 err = ext4_ext_split(handle, inode, path, newext, i);
1138 ext4_ext_drop_refs(path);
1139 path = ext4_ext_find_extent(inode,
1140 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1143 err = PTR_ERR(path);
1145 /* tree is full, time to grow in depth */
1146 err = ext4_ext_grow_indepth(handle, inode, path, newext);
1151 ext4_ext_drop_refs(path);
1152 path = ext4_ext_find_extent(inode,
1153 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1156 err = PTR_ERR(path);
1161 * only first (depth 0 -> 1) produces free space;
1162 * in all other cases we have to split the grown tree
1164 depth = ext_depth(inode);
1165 if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
1166 /* now we need to split */
1176 * search the closest allocated block to the left for *logical
1177 * and returns it at @logical + it's physical address at @phys
1178 * if *logical is the smallest allocated block, the function
1179 * returns 0 at @phys
1180 * return value contains 0 (success) or error code
1183 ext4_ext_search_left(struct inode *inode, struct ext4_ext_path *path,
1184 ext4_lblk_t *logical, ext4_fsblk_t *phys)
1186 struct ext4_extent_idx *ix;
1187 struct ext4_extent *ex;
1190 BUG_ON(path == NULL);
1191 depth = path->p_depth;
1194 if (depth == 0 && path->p_ext == NULL)
1197 /* usually extent in the path covers blocks smaller
1198 * then *logical, but it can be that extent is the
1199 * first one in the file */
1201 ex = path[depth].p_ext;
1202 ee_len = ext4_ext_get_actual_len(ex);
1203 if (*logical < le32_to_cpu(ex->ee_block)) {
1204 BUG_ON(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex);
1205 while (--depth >= 0) {
1206 ix = path[depth].p_idx;
1207 BUG_ON(ix != EXT_FIRST_INDEX(path[depth].p_hdr));
1212 BUG_ON(*logical < (le32_to_cpu(ex->ee_block) + ee_len));
1214 *logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
1215 *phys = ext_pblock(ex) + ee_len - 1;
1220 * search the closest allocated block to the right for *logical
1221 * and returns it at @logical + it's physical address at @phys
1222 * if *logical is the smallest allocated block, the function
1223 * returns 0 at @phys
1224 * return value contains 0 (success) or error code
1227 ext4_ext_search_right(struct inode *inode, struct ext4_ext_path *path,
1228 ext4_lblk_t *logical, ext4_fsblk_t *phys)
1230 struct buffer_head *bh = NULL;
1231 struct ext4_extent_header *eh;
1232 struct ext4_extent_idx *ix;
1233 struct ext4_extent *ex;
1235 int depth; /* Note, NOT eh_depth; depth from top of tree */
1238 BUG_ON(path == NULL);
1239 depth = path->p_depth;
1242 if (depth == 0 && path->p_ext == NULL)
1245 /* usually extent in the path covers blocks smaller
1246 * then *logical, but it can be that extent is the
1247 * first one in the file */
1249 ex = path[depth].p_ext;
1250 ee_len = ext4_ext_get_actual_len(ex);
1251 if (*logical < le32_to_cpu(ex->ee_block)) {
1252 BUG_ON(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex);
1253 while (--depth >= 0) {
1254 ix = path[depth].p_idx;
1255 BUG_ON(ix != EXT_FIRST_INDEX(path[depth].p_hdr));
1257 *logical = le32_to_cpu(ex->ee_block);
1258 *phys = ext_pblock(ex);
1262 BUG_ON(*logical < (le32_to_cpu(ex->ee_block) + ee_len));
1264 if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
1265 /* next allocated block in this leaf */
1267 *logical = le32_to_cpu(ex->ee_block);
1268 *phys = ext_pblock(ex);
1272 /* go up and search for index to the right */
1273 while (--depth >= 0) {
1274 ix = path[depth].p_idx;
1275 if (ix != EXT_LAST_INDEX(path[depth].p_hdr))
1279 /* we've gone up to the root and found no index to the right */
1283 /* we've found index to the right, let's
1284 * follow it and find the closest allocated
1285 * block to the right */
1287 block = idx_pblock(ix);
1288 while (++depth < path->p_depth) {
1289 bh = sb_bread(inode->i_sb, block);
1292 eh = ext_block_hdr(bh);
1293 /* subtract from p_depth to get proper eh_depth */
1294 if (ext4_ext_check(inode, eh, path->p_depth - depth)) {
1298 ix = EXT_FIRST_INDEX(eh);
1299 block = idx_pblock(ix);
1303 bh = sb_bread(inode->i_sb, block);
1306 eh = ext_block_hdr(bh);
1307 if (ext4_ext_check(inode, eh, path->p_depth - depth)) {
1311 ex = EXT_FIRST_EXTENT(eh);
1312 *logical = le32_to_cpu(ex->ee_block);
1313 *phys = ext_pblock(ex);
1319 * ext4_ext_next_allocated_block:
1320 * returns allocated block in subsequent extent or EXT_MAX_BLOCK.
1321 * NOTE: it considers block number from index entry as
1322 * allocated block. Thus, index entries have to be consistent
1326 ext4_ext_next_allocated_block(struct ext4_ext_path *path)
1330 BUG_ON(path == NULL);
1331 depth = path->p_depth;
1333 if (depth == 0 && path->p_ext == NULL)
1334 return EXT_MAX_BLOCK;
1336 while (depth >= 0) {
1337 if (depth == path->p_depth) {
1339 if (path[depth].p_ext !=
1340 EXT_LAST_EXTENT(path[depth].p_hdr))
1341 return le32_to_cpu(path[depth].p_ext[1].ee_block);
1344 if (path[depth].p_idx !=
1345 EXT_LAST_INDEX(path[depth].p_hdr))
1346 return le32_to_cpu(path[depth].p_idx[1].ei_block);
1351 return EXT_MAX_BLOCK;
1355 * ext4_ext_next_leaf_block:
1356 * returns first allocated block from next leaf or EXT_MAX_BLOCK
1358 static ext4_lblk_t ext4_ext_next_leaf_block(struct inode *inode,
1359 struct ext4_ext_path *path)
1363 BUG_ON(path == NULL);
1364 depth = path->p_depth;
1366 /* zero-tree has no leaf blocks at all */
1368 return EXT_MAX_BLOCK;
1370 /* go to index block */
1373 while (depth >= 0) {
1374 if (path[depth].p_idx !=
1375 EXT_LAST_INDEX(path[depth].p_hdr))
1376 return (ext4_lblk_t)
1377 le32_to_cpu(path[depth].p_idx[1].ei_block);
1381 return EXT_MAX_BLOCK;
1385 * ext4_ext_correct_indexes:
1386 * if leaf gets modified and modified extent is first in the leaf,
1387 * then we have to correct all indexes above.
1388 * TODO: do we need to correct tree in all cases?
1390 static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
1391 struct ext4_ext_path *path)
1393 struct ext4_extent_header *eh;
1394 int depth = ext_depth(inode);
1395 struct ext4_extent *ex;
1399 eh = path[depth].p_hdr;
1400 ex = path[depth].p_ext;
1405 /* there is no tree at all */
1409 if (ex != EXT_FIRST_EXTENT(eh)) {
1410 /* we correct tree if first leaf got modified only */
1415 * TODO: we need correction if border is smaller than current one
1418 border = path[depth].p_ext->ee_block;
1419 err = ext4_ext_get_access(handle, inode, path + k);
1422 path[k].p_idx->ei_block = border;
1423 err = ext4_ext_dirty(handle, inode, path + k);
1428 /* change all left-side indexes */
1429 if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
1431 err = ext4_ext_get_access(handle, inode, path + k);
1434 path[k].p_idx->ei_block = border;
1435 err = ext4_ext_dirty(handle, inode, path + k);
1444 ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
1445 struct ext4_extent *ex2)
1447 unsigned short ext1_ee_len, ext2_ee_len, max_len;
1450 * Make sure that either both extents are uninitialized, or
1453 if (ext4_ext_is_uninitialized(ex1) ^ ext4_ext_is_uninitialized(ex2))
1456 if (ext4_ext_is_uninitialized(ex1))
1457 max_len = EXT_UNINIT_MAX_LEN;
1459 max_len = EXT_INIT_MAX_LEN;
1461 ext1_ee_len = ext4_ext_get_actual_len(ex1);
1462 ext2_ee_len = ext4_ext_get_actual_len(ex2);
1464 if (le32_to_cpu(ex1->ee_block) + ext1_ee_len !=
1465 le32_to_cpu(ex2->ee_block))
1469 * To allow future support for preallocated extents to be added
1470 * as an RO_COMPAT feature, refuse to merge to extents if
1471 * this can result in the top bit of ee_len being set.
1473 if (ext1_ee_len + ext2_ee_len > max_len)
1475 #ifdef AGGRESSIVE_TEST
1476 if (ext1_ee_len >= 4)
1480 if (ext_pblock(ex1) + ext1_ee_len == ext_pblock(ex2))
1486 * This function tries to merge the "ex" extent to the next extent in the tree.
1487 * It always tries to merge towards right. If you want to merge towards
1488 * left, pass "ex - 1" as argument instead of "ex".
1489 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1490 * 1 if they got merged.
1492 int ext4_ext_try_to_merge(struct inode *inode,
1493 struct ext4_ext_path *path,
1494 struct ext4_extent *ex)
1496 struct ext4_extent_header *eh;
1497 unsigned int depth, len;
1499 int uninitialized = 0;
1501 depth = ext_depth(inode);
1502 BUG_ON(path[depth].p_hdr == NULL);
1503 eh = path[depth].p_hdr;
1505 while (ex < EXT_LAST_EXTENT(eh)) {
1506 if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
1508 /* merge with next extent! */
1509 if (ext4_ext_is_uninitialized(ex))
1511 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1512 + ext4_ext_get_actual_len(ex + 1));
1514 ext4_ext_mark_uninitialized(ex);
1516 if (ex + 1 < EXT_LAST_EXTENT(eh)) {
1517 len = (EXT_LAST_EXTENT(eh) - ex - 1)
1518 * sizeof(struct ext4_extent);
1519 memmove(ex + 1, ex + 2, len);
1521 le16_add_cpu(&eh->eh_entries, -1);
1523 WARN_ON(eh->eh_entries == 0);
1524 if (!eh->eh_entries)
1525 ext4_error(inode->i_sb, "ext4_ext_try_to_merge",
1526 "inode#%lu, eh->eh_entries = 0!", inode->i_ino);
1533 * check if a portion of the "newext" extent overlaps with an
1536 * If there is an overlap discovered, it updates the length of the newext
1537 * such that there will be no overlap, and then returns 1.
1538 * If there is no overlap found, it returns 0.
1540 unsigned int ext4_ext_check_overlap(struct inode *inode,
1541 struct ext4_extent *newext,
1542 struct ext4_ext_path *path)
1545 unsigned int depth, len1;
1546 unsigned int ret = 0;
1548 b1 = le32_to_cpu(newext->ee_block);
1549 len1 = ext4_ext_get_actual_len(newext);
1550 depth = ext_depth(inode);
1551 if (!path[depth].p_ext)
1553 b2 = le32_to_cpu(path[depth].p_ext->ee_block);
1556 * get the next allocated block if the extent in the path
1557 * is before the requested block(s)
1560 b2 = ext4_ext_next_allocated_block(path);
1561 if (b2 == EXT_MAX_BLOCK)
1565 /* check for wrap through zero on extent logical start block*/
1566 if (b1 + len1 < b1) {
1567 len1 = EXT_MAX_BLOCK - b1;
1568 newext->ee_len = cpu_to_le16(len1);
1572 /* check for overlap */
1573 if (b1 + len1 > b2) {
1574 newext->ee_len = cpu_to_le16(b2 - b1);
1582 * ext4_ext_insert_extent:
1583 * tries to merge requsted extent into the existing extent or
1584 * inserts requested extent as new one into the tree,
1585 * creating new leaf in the no-space case.
1587 int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
1588 struct ext4_ext_path *path,
1589 struct ext4_extent *newext)
1591 struct ext4_extent_header *eh;
1592 struct ext4_extent *ex, *fex;
1593 struct ext4_extent *nearex; /* nearest extent */
1594 struct ext4_ext_path *npath = NULL;
1595 int depth, len, err;
1597 unsigned uninitialized = 0;
1599 BUG_ON(ext4_ext_get_actual_len(newext) == 0);
1600 depth = ext_depth(inode);
1601 ex = path[depth].p_ext;
1602 BUG_ON(path[depth].p_hdr == NULL);
1604 /* try to insert block into found extent and return */
1605 if (ex && ext4_can_extents_be_merged(inode, ex, newext)) {
1606 ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
1607 ext4_ext_is_uninitialized(newext),
1608 ext4_ext_get_actual_len(newext),
1609 le32_to_cpu(ex->ee_block),
1610 ext4_ext_is_uninitialized(ex),
1611 ext4_ext_get_actual_len(ex), ext_pblock(ex));
1612 err = ext4_ext_get_access(handle, inode, path + depth);
1617 * ext4_can_extents_be_merged should have checked that either
1618 * both extents are uninitialized, or both aren't. Thus we
1619 * need to check only one of them here.
1621 if (ext4_ext_is_uninitialized(ex))
1623 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1624 + ext4_ext_get_actual_len(newext));
1626 ext4_ext_mark_uninitialized(ex);
1627 eh = path[depth].p_hdr;
1633 depth = ext_depth(inode);
1634 eh = path[depth].p_hdr;
1635 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
1638 /* probably next leaf has space for us? */
1639 fex = EXT_LAST_EXTENT(eh);
1640 next = ext4_ext_next_leaf_block(inode, path);
1641 if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block)
1642 && next != EXT_MAX_BLOCK) {
1643 ext_debug("next leaf block - %d\n", next);
1644 BUG_ON(npath != NULL);
1645 npath = ext4_ext_find_extent(inode, next, NULL);
1647 return PTR_ERR(npath);
1648 BUG_ON(npath->p_depth != path->p_depth);
1649 eh = npath[depth].p_hdr;
1650 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
1651 ext_debug("next leaf isnt full(%d)\n",
1652 le16_to_cpu(eh->eh_entries));
1656 ext_debug("next leaf has no free space(%d,%d)\n",
1657 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
1661 * There is no free space in the found leaf.
1662 * We're gonna add a new leaf in the tree.
1664 err = ext4_ext_create_new_leaf(handle, inode, path, newext);
1667 depth = ext_depth(inode);
1668 eh = path[depth].p_hdr;
1671 nearex = path[depth].p_ext;
1673 err = ext4_ext_get_access(handle, inode, path + depth);
1678 /* there is no extent in this leaf, create first one */
1679 ext_debug("first extent in the leaf: %d:%llu:[%d]%d\n",
1680 le32_to_cpu(newext->ee_block),
1682 ext4_ext_is_uninitialized(newext),
1683 ext4_ext_get_actual_len(newext));
1684 path[depth].p_ext = EXT_FIRST_EXTENT(eh);
1685 } else if (le32_to_cpu(newext->ee_block)
1686 > le32_to_cpu(nearex->ee_block)) {
1687 /* BUG_ON(newext->ee_block == nearex->ee_block); */
1688 if (nearex != EXT_LAST_EXTENT(eh)) {
1689 len = EXT_MAX_EXTENT(eh) - nearex;
1690 len = (len - 1) * sizeof(struct ext4_extent);
1691 len = len < 0 ? 0 : len;
1692 ext_debug("insert %d:%llu:[%d]%d after: nearest 0x%p, "
1693 "move %d from 0x%p to 0x%p\n",
1694 le32_to_cpu(newext->ee_block),
1696 ext4_ext_is_uninitialized(newext),
1697 ext4_ext_get_actual_len(newext),
1698 nearex, len, nearex + 1, nearex + 2);
1699 memmove(nearex + 2, nearex + 1, len);
1701 path[depth].p_ext = nearex + 1;
1703 BUG_ON(newext->ee_block == nearex->ee_block);
1704 len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent);
1705 len = len < 0 ? 0 : len;
1706 ext_debug("insert %d:%llu:[%d]%d before: nearest 0x%p, "
1707 "move %d from 0x%p to 0x%p\n",
1708 le32_to_cpu(newext->ee_block),
1710 ext4_ext_is_uninitialized(newext),
1711 ext4_ext_get_actual_len(newext),
1712 nearex, len, nearex + 1, nearex + 2);
1713 memmove(nearex + 1, nearex, len);
1714 path[depth].p_ext = nearex;
1717 le16_add_cpu(&eh->eh_entries, 1);
1718 nearex = path[depth].p_ext;
1719 nearex->ee_block = newext->ee_block;
1720 ext4_ext_store_pblock(nearex, ext_pblock(newext));
1721 nearex->ee_len = newext->ee_len;
1724 /* try to merge extents to the right */
1725 ext4_ext_try_to_merge(inode, path, nearex);
1727 /* try to merge extents to the left */
1729 /* time to correct all indexes above */
1730 err = ext4_ext_correct_indexes(handle, inode, path);
1734 err = ext4_ext_dirty(handle, inode, path + depth);
1738 ext4_ext_drop_refs(npath);
1741 ext4_ext_invalidate_cache(inode);
1745 int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
1746 ext4_lblk_t num, ext_prepare_callback func,
1749 struct ext4_ext_path *path = NULL;
1750 struct ext4_ext_cache cbex;
1751 struct ext4_extent *ex;
1752 ext4_lblk_t next, start = 0, end = 0;
1753 ext4_lblk_t last = block + num;
1754 int depth, exists, err = 0;
1756 BUG_ON(func == NULL);
1757 BUG_ON(inode == NULL);
1759 while (block < last && block != EXT_MAX_BLOCK) {
1761 /* find extent for this block */
1762 path = ext4_ext_find_extent(inode, block, path);
1764 err = PTR_ERR(path);
1769 depth = ext_depth(inode);
1770 BUG_ON(path[depth].p_hdr == NULL);
1771 ex = path[depth].p_ext;
1772 next = ext4_ext_next_allocated_block(path);
1776 /* there is no extent yet, so try to allocate
1777 * all requested space */
1780 } else if (le32_to_cpu(ex->ee_block) > block) {
1781 /* need to allocate space before found extent */
1783 end = le32_to_cpu(ex->ee_block);
1784 if (block + num < end)
1786 } else if (block >= le32_to_cpu(ex->ee_block)
1787 + ext4_ext_get_actual_len(ex)) {
1788 /* need to allocate space after found extent */
1793 } else if (block >= le32_to_cpu(ex->ee_block)) {
1795 * some part of requested space is covered
1799 end = le32_to_cpu(ex->ee_block)
1800 + ext4_ext_get_actual_len(ex);
1801 if (block + num < end)
1807 BUG_ON(end <= start);
1810 cbex.ec_block = start;
1811 cbex.ec_len = end - start;
1813 cbex.ec_type = EXT4_EXT_CACHE_GAP;
1815 cbex.ec_block = le32_to_cpu(ex->ee_block);
1816 cbex.ec_len = ext4_ext_get_actual_len(ex);
1817 cbex.ec_start = ext_pblock(ex);
1818 cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
1821 BUG_ON(cbex.ec_len == 0);
1822 err = func(inode, path, &cbex, ex, cbdata);
1823 ext4_ext_drop_refs(path);
1828 if (err == EXT_REPEAT)
1830 else if (err == EXT_BREAK) {
1835 if (ext_depth(inode) != depth) {
1836 /* depth was changed. we have to realloc path */
1841 block = cbex.ec_block + cbex.ec_len;
1845 ext4_ext_drop_refs(path);
1853 ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block,
1854 __u32 len, ext4_fsblk_t start, int type)
1856 struct ext4_ext_cache *cex;
1858 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
1859 cex = &EXT4_I(inode)->i_cached_extent;
1860 cex->ec_type = type;
1861 cex->ec_block = block;
1863 cex->ec_start = start;
1864 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
1868 * ext4_ext_put_gap_in_cache:
1869 * calculate boundaries of the gap that the requested block fits into
1870 * and cache this gap
1873 ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
1876 int depth = ext_depth(inode);
1879 struct ext4_extent *ex;
1881 ex = path[depth].p_ext;
1883 /* there is no extent yet, so gap is [0;-] */
1885 len = EXT_MAX_BLOCK;
1886 ext_debug("cache gap(whole file):");
1887 } else if (block < le32_to_cpu(ex->ee_block)) {
1889 len = le32_to_cpu(ex->ee_block) - block;
1890 ext_debug("cache gap(before): %u [%u:%u]",
1892 le32_to_cpu(ex->ee_block),
1893 ext4_ext_get_actual_len(ex));
1894 } else if (block >= le32_to_cpu(ex->ee_block)
1895 + ext4_ext_get_actual_len(ex)) {
1897 lblock = le32_to_cpu(ex->ee_block)
1898 + ext4_ext_get_actual_len(ex);
1900 next = ext4_ext_next_allocated_block(path);
1901 ext_debug("cache gap(after): [%u:%u] %u",
1902 le32_to_cpu(ex->ee_block),
1903 ext4_ext_get_actual_len(ex),
1905 BUG_ON(next == lblock);
1906 len = next - lblock;
1912 ext_debug(" -> %u:%lu\n", lblock, len);
1913 ext4_ext_put_in_cache(inode, lblock, len, 0, EXT4_EXT_CACHE_GAP);
1917 ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block,
1918 struct ext4_extent *ex)
1920 struct ext4_ext_cache *cex;
1921 int ret = EXT4_EXT_CACHE_NO;
1924 * We borrow i_block_reservation_lock to protect i_cached_extent
1926 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
1927 cex = &EXT4_I(inode)->i_cached_extent;
1929 /* has cache valid data? */
1930 if (cex->ec_type == EXT4_EXT_CACHE_NO)
1933 BUG_ON(cex->ec_type != EXT4_EXT_CACHE_GAP &&
1934 cex->ec_type != EXT4_EXT_CACHE_EXTENT);
1935 if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) {
1936 ex->ee_block = cpu_to_le32(cex->ec_block);
1937 ext4_ext_store_pblock(ex, cex->ec_start);
1938 ex->ee_len = cpu_to_le16(cex->ec_len);
1939 ext_debug("%u cached by %u:%u:%llu\n",
1941 cex->ec_block, cex->ec_len, cex->ec_start);
1945 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
1951 * removes index from the index block.
1952 * It's used in truncate case only, thus all requests are for
1953 * last index in the block only.
1955 static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
1956 struct ext4_ext_path *path)
1958 struct buffer_head *bh;
1962 /* free index block */
1964 leaf = idx_pblock(path->p_idx);
1965 BUG_ON(path->p_hdr->eh_entries == 0);
1966 err = ext4_ext_get_access(handle, inode, path);
1969 le16_add_cpu(&path->p_hdr->eh_entries, -1);
1970 err = ext4_ext_dirty(handle, inode, path);
1973 ext_debug("index is empty, remove it, free block %llu\n", leaf);
1974 bh = sb_find_get_block(inode->i_sb, leaf);
1975 ext4_forget(handle, 1, inode, bh, leaf);
1976 ext4_free_blocks(handle, inode, leaf, 1, 1);
1981 * ext4_ext_calc_credits_for_single_extent:
1982 * This routine returns max. credits that needed to insert an extent
1983 * to the extent tree.
1984 * When pass the actual path, the caller should calculate credits
1987 int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks,
1988 struct ext4_ext_path *path)
1991 int depth = ext_depth(inode);
1994 /* probably there is space in leaf? */
1995 if (le16_to_cpu(path[depth].p_hdr->eh_entries)
1996 < le16_to_cpu(path[depth].p_hdr->eh_max)) {
1999 * There are some space in the leaf tree, no
2000 * need to account for leaf block credit
2002 * bitmaps and block group descriptor blocks
2003 * and other metadat blocks still need to be
2006 /* 1 bitmap, 1 block group descriptor */
2007 ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb);
2012 return ext4_chunk_trans_blocks(inode, nrblocks);
2016 * How many index/leaf blocks need to change/allocate to modify nrblocks?
2018 * if nrblocks are fit in a single extent (chunk flag is 1), then
2019 * in the worse case, each tree level index/leaf need to be changed
2020 * if the tree split due to insert a new extent, then the old tree
2021 * index/leaf need to be updated too
2023 * If the nrblocks are discontiguous, they could cause
2024 * the whole tree split more than once, but this is really rare.
2026 int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
2029 int depth = ext_depth(inode);
2039 static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
2040 struct ext4_extent *ex,
2041 ext4_lblk_t from, ext4_lblk_t to)
2043 struct buffer_head *bh;
2044 unsigned short ee_len = ext4_ext_get_actual_len(ex);
2045 int i, metadata = 0;
2047 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2049 #ifdef EXTENTS_STATS
2051 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2052 spin_lock(&sbi->s_ext_stats_lock);
2053 sbi->s_ext_blocks += ee_len;
2054 sbi->s_ext_extents++;
2055 if (ee_len < sbi->s_ext_min)
2056 sbi->s_ext_min = ee_len;
2057 if (ee_len > sbi->s_ext_max)
2058 sbi->s_ext_max = ee_len;
2059 if (ext_depth(inode) > sbi->s_depth_max)
2060 sbi->s_depth_max = ext_depth(inode);
2061 spin_unlock(&sbi->s_ext_stats_lock);
2064 if (from >= le32_to_cpu(ex->ee_block)
2065 && to == le32_to_cpu(ex->ee_block) + ee_len - 1) {
2070 num = le32_to_cpu(ex->ee_block) + ee_len - from;
2071 start = ext_pblock(ex) + ee_len - num;
2072 ext_debug("free last %u blocks starting %llu\n", num, start);
2073 for (i = 0; i < num; i++) {
2074 bh = sb_find_get_block(inode->i_sb, start + i);
2075 ext4_forget(handle, 0, inode, bh, start + i);
2077 ext4_free_blocks(handle, inode, start, num, metadata);
2078 } else if (from == le32_to_cpu(ex->ee_block)
2079 && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
2080 printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n",
2081 from, to, le32_to_cpu(ex->ee_block), ee_len);
2083 printk(KERN_INFO "strange request: removal(2) "
2084 "%u-%u from %u:%u\n",
2085 from, to, le32_to_cpu(ex->ee_block), ee_len);
2091 ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
2092 struct ext4_ext_path *path, ext4_lblk_t start)
2094 int err = 0, correct_index = 0;
2095 int depth = ext_depth(inode), credits;
2096 struct ext4_extent_header *eh;
2097 ext4_lblk_t a, b, block;
2099 ext4_lblk_t ex_ee_block;
2100 unsigned short ex_ee_len;
2101 unsigned uninitialized = 0;
2102 struct ext4_extent *ex;
2104 /* the header must be checked already in ext4_ext_remove_space() */
2105 ext_debug("truncate since %u in leaf\n", start);
2106 if (!path[depth].p_hdr)
2107 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
2108 eh = path[depth].p_hdr;
2111 /* find where to start removing */
2112 ex = EXT_LAST_EXTENT(eh);
2114 ex_ee_block = le32_to_cpu(ex->ee_block);
2115 ex_ee_len = ext4_ext_get_actual_len(ex);
2117 while (ex >= EXT_FIRST_EXTENT(eh) &&
2118 ex_ee_block + ex_ee_len > start) {
2120 if (ext4_ext_is_uninitialized(ex))
2125 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block,
2126 uninitialized, ex_ee_len);
2127 path[depth].p_ext = ex;
2129 a = ex_ee_block > start ? ex_ee_block : start;
2130 b = ex_ee_block + ex_ee_len - 1 < EXT_MAX_BLOCK ?
2131 ex_ee_block + ex_ee_len - 1 : EXT_MAX_BLOCK;
2133 ext_debug(" border %u:%u\n", a, b);
2135 if (a != ex_ee_block && b != ex_ee_block + ex_ee_len - 1) {
2139 } else if (a != ex_ee_block) {
2140 /* remove tail of the extent */
2141 block = ex_ee_block;
2143 } else if (b != ex_ee_block + ex_ee_len - 1) {
2144 /* remove head of the extent */
2147 /* there is no "make a hole" API yet */
2150 /* remove whole extent: excellent! */
2151 block = ex_ee_block;
2153 BUG_ON(a != ex_ee_block);
2154 BUG_ON(b != ex_ee_block + ex_ee_len - 1);
2158 * 3 for leaf, sb, and inode plus 2 (bmap and group
2159 * descriptor) for each block group; assume two block
2160 * groups plus ex_ee_len/blocks_per_block_group for
2163 credits = 7 + 2*(ex_ee_len/EXT4_BLOCKS_PER_GROUP(inode->i_sb));
2164 if (ex == EXT_FIRST_EXTENT(eh)) {
2166 credits += (ext_depth(inode)) + 1;
2168 credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
2170 err = ext4_ext_truncate_extend_restart(handle, inode, credits);
2174 err = ext4_ext_get_access(handle, inode, path + depth);
2178 err = ext4_remove_blocks(handle, inode, ex, a, b);
2183 /* this extent is removed; mark slot entirely unused */
2184 ext4_ext_store_pblock(ex, 0);
2185 le16_add_cpu(&eh->eh_entries, -1);
2188 ex->ee_block = cpu_to_le32(block);
2189 ex->ee_len = cpu_to_le16(num);
2191 * Do not mark uninitialized if all the blocks in the
2192 * extent have been removed.
2194 if (uninitialized && num)
2195 ext4_ext_mark_uninitialized(ex);
2197 err = ext4_ext_dirty(handle, inode, path + depth);
2201 ext_debug("new extent: %u:%u:%llu\n", block, num,
2204 ex_ee_block = le32_to_cpu(ex->ee_block);
2205 ex_ee_len = ext4_ext_get_actual_len(ex);
2208 if (correct_index && eh->eh_entries)
2209 err = ext4_ext_correct_indexes(handle, inode, path);
2211 /* if this leaf is free, then we should
2212 * remove it from index block above */
2213 if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
2214 err = ext4_ext_rm_idx(handle, inode, path + depth);
2221 * ext4_ext_more_to_rm:
2222 * returns 1 if current index has to be freed (even partial)
2225 ext4_ext_more_to_rm(struct ext4_ext_path *path)
2227 BUG_ON(path->p_idx == NULL);
2229 if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
2233 * if truncate on deeper level happened, it wasn't partial,
2234 * so we have to consider current index for truncation
2236 if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
2241 static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start)
2243 struct super_block *sb = inode->i_sb;
2244 int depth = ext_depth(inode);
2245 struct ext4_ext_path *path;
2249 ext_debug("truncate since %u\n", start);
2251 /* probably first extent we're gonna free will be last in block */
2252 handle = ext4_journal_start(inode, depth + 1);
2254 return PTR_ERR(handle);
2256 ext4_ext_invalidate_cache(inode);
2259 * We start scanning from right side, freeing all the blocks
2260 * after i_size and walking into the tree depth-wise.
2262 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_NOFS);
2264 ext4_journal_stop(handle);
2267 path[0].p_hdr = ext_inode_hdr(inode);
2268 if (ext4_ext_check(inode, path[0].p_hdr, depth)) {
2272 path[0].p_depth = depth;
2274 while (i >= 0 && err == 0) {
2276 /* this is leaf block */
2277 err = ext4_ext_rm_leaf(handle, inode, path, start);
2278 /* root level has p_bh == NULL, brelse() eats this */
2279 brelse(path[i].p_bh);
2280 path[i].p_bh = NULL;
2285 /* this is index block */
2286 if (!path[i].p_hdr) {
2287 ext_debug("initialize header\n");
2288 path[i].p_hdr = ext_block_hdr(path[i].p_bh);
2291 if (!path[i].p_idx) {
2292 /* this level hasn't been touched yet */
2293 path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
2294 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
2295 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2297 le16_to_cpu(path[i].p_hdr->eh_entries));
2299 /* we were already here, see at next index */
2303 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2304 i, EXT_FIRST_INDEX(path[i].p_hdr),
2306 if (ext4_ext_more_to_rm(path + i)) {
2307 struct buffer_head *bh;
2308 /* go to the next level */
2309 ext_debug("move to level %d (block %llu)\n",
2310 i + 1, idx_pblock(path[i].p_idx));
2311 memset(path + i + 1, 0, sizeof(*path));
2312 bh = sb_bread(sb, idx_pblock(path[i].p_idx));
2314 /* should we reset i_size? */
2318 if (WARN_ON(i + 1 > depth)) {
2322 if (ext4_ext_check(inode, ext_block_hdr(bh),
2327 path[i + 1].p_bh = bh;
2329 /* save actual number of indexes since this
2330 * number is changed at the next iteration */
2331 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
2334 /* we finished processing this index, go up */
2335 if (path[i].p_hdr->eh_entries == 0 && i > 0) {
2336 /* index is empty, remove it;
2337 * handle must be already prepared by the
2338 * truncatei_leaf() */
2339 err = ext4_ext_rm_idx(handle, inode, path + i);
2341 /* root level has p_bh == NULL, brelse() eats this */
2342 brelse(path[i].p_bh);
2343 path[i].p_bh = NULL;
2345 ext_debug("return to level %d\n", i);
2349 /* TODO: flexible tree reduction should be here */
2350 if (path->p_hdr->eh_entries == 0) {
2352 * truncate to zero freed all the tree,
2353 * so we need to correct eh_depth
2355 err = ext4_ext_get_access(handle, inode, path);
2357 ext_inode_hdr(inode)->eh_depth = 0;
2358 ext_inode_hdr(inode)->eh_max =
2359 cpu_to_le16(ext4_ext_space_root(inode, 0));
2360 err = ext4_ext_dirty(handle, inode, path);
2364 ext4_ext_drop_refs(path);
2366 ext4_journal_stop(handle);
2372 * called at mount time
2374 void ext4_ext_init(struct super_block *sb)
2377 * possible initialization would be here
2380 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2381 printk(KERN_INFO "EXT4-fs: file extents enabled");
2382 #ifdef AGGRESSIVE_TEST
2383 printk(", aggressive tests");
2385 #ifdef CHECK_BINSEARCH
2386 printk(", check binsearch");
2388 #ifdef EXTENTS_STATS
2392 #ifdef EXTENTS_STATS
2393 spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
2394 EXT4_SB(sb)->s_ext_min = 1 << 30;
2395 EXT4_SB(sb)->s_ext_max = 0;
2401 * called at umount time
2403 void ext4_ext_release(struct super_block *sb)
2405 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2408 #ifdef EXTENTS_STATS
2409 if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
2410 struct ext4_sb_info *sbi = EXT4_SB(sb);
2411 printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2412 sbi->s_ext_blocks, sbi->s_ext_extents,
2413 sbi->s_ext_blocks / sbi->s_ext_extents);
2414 printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2415 sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
2420 static void bi_complete(struct bio *bio, int error)
2422 complete((struct completion *)bio->bi_private);
2425 /* FIXME!! we need to try to merge to left or right after zero-out */
2426 static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
2430 int blkbits, blocksize;
2432 struct completion event;
2433 unsigned int ee_len, len, done, offset;
2436 blkbits = inode->i_blkbits;
2437 blocksize = inode->i_sb->s_blocksize;
2438 ee_len = ext4_ext_get_actual_len(ex);
2439 ee_pblock = ext_pblock(ex);
2441 /* convert ee_pblock to 512 byte sectors */
2442 ee_pblock = ee_pblock << (blkbits - 9);
2444 while (ee_len > 0) {
2446 if (ee_len > BIO_MAX_PAGES)
2447 len = BIO_MAX_PAGES;
2451 bio = bio_alloc(GFP_NOIO, len);
2452 bio->bi_sector = ee_pblock;
2453 bio->bi_bdev = inode->i_sb->s_bdev;
2457 while (done < len) {
2458 ret = bio_add_page(bio, ZERO_PAGE(0),
2460 if (ret != blocksize) {
2462 * We can't add any more pages because of
2463 * hardware limitations. Start a new bio.
2468 offset += blocksize;
2469 if (offset >= PAGE_CACHE_SIZE)
2473 init_completion(&event);
2474 bio->bi_private = &event;
2475 bio->bi_end_io = bi_complete;
2476 submit_bio(WRITE, bio);
2477 wait_for_completion(&event);
2479 if (test_bit(BIO_UPTODATE, &bio->bi_flags))
2487 ee_pblock += done << (blkbits - 9);
2492 #define EXT4_EXT_ZERO_LEN 7
2495 * This function is called by ext4_ext_get_blocks() if someone tries to write
2496 * to an uninitialized extent. It may result in splitting the uninitialized
2497 * extent into multiple extents (upto three - one initialized and two
2499 * There are three possibilities:
2500 * a> There is no split required: Entire extent should be initialized
2501 * b> Splits in two extents: Write is happening at either end of the extent
2502 * c> Splits in three extents: Somone is writing in middle of the extent
2504 static int ext4_ext_convert_to_initialized(handle_t *handle,
2505 struct inode *inode,
2506 struct ext4_ext_path *path,
2508 unsigned int max_blocks)
2510 struct ext4_extent *ex, newex, orig_ex;
2511 struct ext4_extent *ex1 = NULL;
2512 struct ext4_extent *ex2 = NULL;
2513 struct ext4_extent *ex3 = NULL;
2514 struct ext4_extent_header *eh;
2515 ext4_lblk_t ee_block;
2516 unsigned int allocated, ee_len, depth;
2517 ext4_fsblk_t newblock;
2521 depth = ext_depth(inode);
2522 eh = path[depth].p_hdr;
2523 ex = path[depth].p_ext;
2524 ee_block = le32_to_cpu(ex->ee_block);
2525 ee_len = ext4_ext_get_actual_len(ex);
2526 allocated = ee_len - (iblock - ee_block);
2527 newblock = iblock - ee_block + ext_pblock(ex);
2529 orig_ex.ee_block = ex->ee_block;
2530 orig_ex.ee_len = cpu_to_le16(ee_len);
2531 ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));
2533 err = ext4_ext_get_access(handle, inode, path + depth);
2536 /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
2537 if (ee_len <= 2*EXT4_EXT_ZERO_LEN) {
2538 err = ext4_ext_zeroout(inode, &orig_ex);
2540 goto fix_extent_len;
2541 /* update the extent length and mark as initialized */
2542 ex->ee_block = orig_ex.ee_block;
2543 ex->ee_len = orig_ex.ee_len;
2544 ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
2545 ext4_ext_dirty(handle, inode, path + depth);
2546 /* zeroed the full extent */
2550 /* ex1: ee_block to iblock - 1 : uninitialized */
2551 if (iblock > ee_block) {
2553 ex1->ee_len = cpu_to_le16(iblock - ee_block);
2554 ext4_ext_mark_uninitialized(ex1);
2558 * for sanity, update the length of the ex2 extent before
2559 * we insert ex3, if ex1 is NULL. This is to avoid temporary
2560 * overlap of blocks.
2562 if (!ex1 && allocated > max_blocks)
2563 ex2->ee_len = cpu_to_le16(max_blocks);
2564 /* ex3: to ee_block + ee_len : uninitialised */
2565 if (allocated > max_blocks) {
2566 unsigned int newdepth;
2567 /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */
2568 if (allocated <= EXT4_EXT_ZERO_LEN) {
2570 * iblock == ee_block is handled by the zerouout
2572 * Mark first half uninitialized.
2573 * Mark second half initialized and zero out the
2574 * initialized extent
2576 ex->ee_block = orig_ex.ee_block;
2577 ex->ee_len = cpu_to_le16(ee_len - allocated);
2578 ext4_ext_mark_uninitialized(ex);
2579 ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
2580 ext4_ext_dirty(handle, inode, path + depth);
2583 ex3->ee_block = cpu_to_le32(iblock);
2584 ext4_ext_store_pblock(ex3, newblock);
2585 ex3->ee_len = cpu_to_le16(allocated);
2586 err = ext4_ext_insert_extent(handle, inode, path, ex3);
2587 if (err == -ENOSPC) {
2588 err = ext4_ext_zeroout(inode, &orig_ex);
2590 goto fix_extent_len;
2591 ex->ee_block = orig_ex.ee_block;
2592 ex->ee_len = orig_ex.ee_len;
2593 ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
2594 ext4_ext_dirty(handle, inode, path + depth);
2595 /* blocks available from iblock */
2599 goto fix_extent_len;
2602 * We need to zero out the second half because
2603 * an fallocate request can update file size and
2604 * converting the second half to initialized extent
2605 * implies that we can leak some junk data to user
2608 err = ext4_ext_zeroout(inode, ex3);
2611 * We should actually mark the
2612 * second half as uninit and return error
2613 * Insert would have changed the extent
2615 depth = ext_depth(inode);
2616 ext4_ext_drop_refs(path);
2617 path = ext4_ext_find_extent(inode,
2620 err = PTR_ERR(path);
2623 /* get the second half extent details */
2624 ex = path[depth].p_ext;
2625 err = ext4_ext_get_access(handle, inode,
2629 ext4_ext_mark_uninitialized(ex);
2630 ext4_ext_dirty(handle, inode, path + depth);
2634 /* zeroed the second half */
2638 ex3->ee_block = cpu_to_le32(iblock + max_blocks);
2639 ext4_ext_store_pblock(ex3, newblock + max_blocks);
2640 ex3->ee_len = cpu_to_le16(allocated - max_blocks);
2641 ext4_ext_mark_uninitialized(ex3);
2642 err = ext4_ext_insert_extent(handle, inode, path, ex3);
2643 if (err == -ENOSPC) {
2644 err = ext4_ext_zeroout(inode, &orig_ex);
2646 goto fix_extent_len;
2647 /* update the extent length and mark as initialized */
2648 ex->ee_block = orig_ex.ee_block;
2649 ex->ee_len = orig_ex.ee_len;
2650 ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
2651 ext4_ext_dirty(handle, inode, path + depth);
2652 /* zeroed the full extent */
2653 /* blocks available from iblock */
2657 goto fix_extent_len;
2659 * The depth, and hence eh & ex might change
2660 * as part of the insert above.
2662 newdepth = ext_depth(inode);
2664 * update the extent length after successful insert of the
2667 orig_ex.ee_len = cpu_to_le16(ee_len -
2668 ext4_ext_get_actual_len(ex3));
2670 ext4_ext_drop_refs(path);
2671 path = ext4_ext_find_extent(inode, iblock, path);
2673 err = PTR_ERR(path);
2676 eh = path[depth].p_hdr;
2677 ex = path[depth].p_ext;
2681 err = ext4_ext_get_access(handle, inode, path + depth);
2685 allocated = max_blocks;
2687 /* If extent has less than EXT4_EXT_ZERO_LEN and we are trying
2688 * to insert a extent in the middle zerout directly
2689 * otherwise give the extent a chance to merge to left
2691 if (le16_to_cpu(orig_ex.ee_len) <= EXT4_EXT_ZERO_LEN &&
2692 iblock != ee_block) {
2693 err = ext4_ext_zeroout(inode, &orig_ex);
2695 goto fix_extent_len;
2696 /* update the extent length and mark as initialized */
2697 ex->ee_block = orig_ex.ee_block;
2698 ex->ee_len = orig_ex.ee_len;
2699 ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
2700 ext4_ext_dirty(handle, inode, path + depth);
2701 /* zero out the first half */
2702 /* blocks available from iblock */
2707 * If there was a change of depth as part of the
2708 * insertion of ex3 above, we need to update the length
2709 * of the ex1 extent again here
2711 if (ex1 && ex1 != ex) {
2713 ex1->ee_len = cpu_to_le16(iblock - ee_block);
2714 ext4_ext_mark_uninitialized(ex1);
2717 /* ex2: iblock to iblock + maxblocks-1 : initialised */
2718 ex2->ee_block = cpu_to_le32(iblock);
2719 ext4_ext_store_pblock(ex2, newblock);
2720 ex2->ee_len = cpu_to_le16(allocated);
2724 * New (initialized) extent starts from the first block
2725 * in the current extent. i.e., ex2 == ex
2726 * We have to see if it can be merged with the extent
2729 if (ex2 > EXT_FIRST_EXTENT(eh)) {
2731 * To merge left, pass "ex2 - 1" to try_to_merge(),
2732 * since it merges towards right _only_.
2734 ret = ext4_ext_try_to_merge(inode, path, ex2 - 1);
2736 err = ext4_ext_correct_indexes(handle, inode, path);
2739 depth = ext_depth(inode);
2744 * Try to Merge towards right. This might be required
2745 * only when the whole extent is being written to.
2746 * i.e. ex2 == ex and ex3 == NULL.
2749 ret = ext4_ext_try_to_merge(inode, path, ex2);
2751 err = ext4_ext_correct_indexes(handle, inode, path);
2756 /* Mark modified extent as dirty */
2757 err = ext4_ext_dirty(handle, inode, path + depth);
2760 err = ext4_ext_insert_extent(handle, inode, path, &newex);
2761 if (err == -ENOSPC) {
2762 err = ext4_ext_zeroout(inode, &orig_ex);
2764 goto fix_extent_len;
2765 /* update the extent length and mark as initialized */
2766 ex->ee_block = orig_ex.ee_block;
2767 ex->ee_len = orig_ex.ee_len;
2768 ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
2769 ext4_ext_dirty(handle, inode, path + depth);
2770 /* zero out the first half */
2773 goto fix_extent_len;
2775 ext4_ext_show_leaf(inode, path);
2776 return err ? err : allocated;
2779 ex->ee_block = orig_ex.ee_block;
2780 ex->ee_len = orig_ex.ee_len;
2781 ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
2782 ext4_ext_mark_uninitialized(ex);
2783 ext4_ext_dirty(handle, inode, path + depth);
2788 * Block allocation/map/preallocation routine for extents based files
2791 * Need to be called with
2792 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
2793 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
2795 * return > 0, number of of blocks already mapped/allocated
2796 * if create == 0 and these are pre-allocated blocks
2797 * buffer head is unmapped
2798 * otherwise blocks are mapped
2800 * return = 0, if plain look up failed (blocks have not been allocated)
2801 * buffer head is unmapped
2803 * return < 0, error case.
2805 int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
2807 unsigned int max_blocks, struct buffer_head *bh_result,
2810 struct ext4_ext_path *path = NULL;
2811 struct ext4_extent_header *eh;
2812 struct ext4_extent newex, *ex;
2813 ext4_fsblk_t newblock;
2814 int err = 0, depth, ret, cache_type;
2815 unsigned int allocated = 0;
2816 struct ext4_allocation_request ar;
2818 __clear_bit(BH_New, &bh_result->b_state);
2819 ext_debug("blocks %u/%u requested for inode %lu\n",
2820 iblock, max_blocks, inode->i_ino);
2822 /* check in cache */
2823 cache_type = ext4_ext_in_cache(inode, iblock, &newex);
2825 if (cache_type == EXT4_EXT_CACHE_GAP) {
2826 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
2828 * block isn't allocated yet and
2829 * user doesn't want to allocate it
2833 /* we should allocate requested block */
2834 } else if (cache_type == EXT4_EXT_CACHE_EXTENT) {
2835 /* block is already allocated */
2837 - le32_to_cpu(newex.ee_block)
2838 + ext_pblock(&newex);
2839 /* number of remaining blocks in the extent */
2840 allocated = ext4_ext_get_actual_len(&newex) -
2841 (iblock - le32_to_cpu(newex.ee_block));
2848 /* find extent for this block */
2849 path = ext4_ext_find_extent(inode, iblock, NULL);
2851 err = PTR_ERR(path);
2856 depth = ext_depth(inode);
2859 * consistent leaf must not be empty;
2860 * this situation is possible, though, _during_ tree modification;
2861 * this is why assert can't be put in ext4_ext_find_extent()
2863 BUG_ON(path[depth].p_ext == NULL && depth != 0);
2864 eh = path[depth].p_hdr;
2866 ex = path[depth].p_ext;
2868 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
2869 ext4_fsblk_t ee_start = ext_pblock(ex);
2870 unsigned short ee_len;
2873 * Uninitialized extents are treated as holes, except that
2874 * we split out initialized portions during a write.
2876 ee_len = ext4_ext_get_actual_len(ex);
2877 /* if found extent covers block, simply return it */
2878 if (iblock >= ee_block && iblock < ee_block + ee_len) {
2879 newblock = iblock - ee_block + ee_start;
2880 /* number of remaining blocks in the extent */
2881 allocated = ee_len - (iblock - ee_block);
2882 ext_debug("%u fit into %u:%d -> %llu\n", iblock,
2883 ee_block, ee_len, newblock);
2885 /* Do not put uninitialized extent in the cache */
2886 if (!ext4_ext_is_uninitialized(ex)) {
2887 ext4_ext_put_in_cache(inode, ee_block,
2889 EXT4_EXT_CACHE_EXTENT);
2892 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
2894 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
2895 if (allocated > max_blocks)
2896 allocated = max_blocks;
2898 * We have blocks reserved already. We
2899 * return allocated blocks so that delalloc
2900 * won't do block reservation for us. But
2901 * the buffer head will be unmapped so that
2902 * a read from the block returns 0s.
2904 set_buffer_unwritten(bh_result);
2905 bh_result->b_bdev = inode->i_sb->s_bdev;
2906 bh_result->b_blocknr = newblock;
2910 ret = ext4_ext_convert_to_initialized(handle, inode,
2923 * requested block isn't allocated yet;
2924 * we couldn't try to create block if create flag is zero
2926 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
2928 * put just found gap into cache to speed up
2929 * subsequent requests
2931 ext4_ext_put_gap_in_cache(inode, path, iblock);
2935 * Okay, we need to do block allocation.
2938 /* find neighbour allocated blocks */
2940 err = ext4_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
2944 err = ext4_ext_search_right(inode, path, &ar.lright, &ar.pright);
2949 * See if request is beyond maximum number of blocks we can have in
2950 * a single extent. For an initialized extent this limit is
2951 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
2952 * EXT_UNINIT_MAX_LEN.
2954 if (max_blocks > EXT_INIT_MAX_LEN &&
2955 !(flags & EXT4_GET_BLOCKS_UNINIT_EXT))
2956 max_blocks = EXT_INIT_MAX_LEN;
2957 else if (max_blocks > EXT_UNINIT_MAX_LEN &&
2958 (flags & EXT4_GET_BLOCKS_UNINIT_EXT))
2959 max_blocks = EXT_UNINIT_MAX_LEN;
2961 /* Check if we can really insert (iblock)::(iblock+max_blocks) extent */
2962 newex.ee_block = cpu_to_le32(iblock);
2963 newex.ee_len = cpu_to_le16(max_blocks);
2964 err = ext4_ext_check_overlap(inode, &newex, path);
2966 allocated = ext4_ext_get_actual_len(&newex);
2968 allocated = max_blocks;
2970 /* allocate new block */
2972 ar.goal = ext4_ext_find_goal(inode, path, iblock);
2973 ar.logical = iblock;
2975 if (S_ISREG(inode->i_mode))
2976 ar.flags = EXT4_MB_HINT_DATA;
2978 /* disable in-core preallocation for non-regular files */
2980 newblock = ext4_mb_new_blocks(handle, &ar, &err);
2983 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
2984 ar.goal, newblock, allocated);
2986 /* try to insert new extent into found leaf and return */
2987 ext4_ext_store_pblock(&newex, newblock);
2988 newex.ee_len = cpu_to_le16(ar.len);
2989 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT) /* Mark uninitialized */
2990 ext4_ext_mark_uninitialized(&newex);
2991 err = ext4_ext_insert_extent(handle, inode, path, &newex);
2993 /* free data blocks we just allocated */
2994 /* not a good idea to call discard here directly,
2995 * but otherwise we'd need to call it every free() */
2996 ext4_discard_preallocations(inode);
2997 ext4_free_blocks(handle, inode, ext_pblock(&newex),
2998 ext4_ext_get_actual_len(&newex), 0);
3002 /* previous routine could use block we allocated */
3003 newblock = ext_pblock(&newex);
3004 allocated = ext4_ext_get_actual_len(&newex);
3006 set_buffer_new(bh_result);
3008 /* Cache only when it is _not_ an uninitialized extent */
3009 if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0)
3010 ext4_ext_put_in_cache(inode, iblock, allocated, newblock,
3011 EXT4_EXT_CACHE_EXTENT);
3013 if (allocated > max_blocks)
3014 allocated = max_blocks;
3015 ext4_ext_show_leaf(inode, path);
3016 set_buffer_mapped(bh_result);
3017 bh_result->b_bdev = inode->i_sb->s_bdev;
3018 bh_result->b_blocknr = newblock;
3021 ext4_ext_drop_refs(path);
3024 return err ? err : allocated;
3027 void ext4_ext_truncate(struct inode *inode)
3029 struct address_space *mapping = inode->i_mapping;
3030 struct super_block *sb = inode->i_sb;
3031 ext4_lblk_t last_block;
3036 * probably first extent we're gonna free will be last in block
3038 err = ext4_writepage_trans_blocks(inode);
3039 handle = ext4_journal_start(inode, err);
3043 if (inode->i_size & (sb->s_blocksize - 1))
3044 ext4_block_truncate_page(handle, mapping, inode->i_size);
3046 if (ext4_orphan_add(handle, inode))
3049 down_write(&EXT4_I(inode)->i_data_sem);
3050 ext4_ext_invalidate_cache(inode);
3052 ext4_discard_preallocations(inode);
3055 * TODO: optimization is possible here.
3056 * Probably we need not scan at all,
3057 * because page truncation is enough.
3060 /* we have to know where to truncate from in crash case */
3061 EXT4_I(inode)->i_disksize = inode->i_size;
3062 ext4_mark_inode_dirty(handle, inode);
3064 last_block = (inode->i_size + sb->s_blocksize - 1)
3065 >> EXT4_BLOCK_SIZE_BITS(sb);
3066 err = ext4_ext_remove_space(inode, last_block);
3068 /* In a multi-transaction truncate, we only make the final
3069 * transaction synchronous.
3072 ext4_handle_sync(handle);
3075 up_write(&EXT4_I(inode)->i_data_sem);
3077 * If this was a simple ftruncate() and the file will remain alive,
3078 * then we need to clear up the orphan record which we created above.
3079 * However, if this was a real unlink then we were called by
3080 * ext4_delete_inode(), and we allow that function to clean up the
3081 * orphan info for us.
3084 ext4_orphan_del(handle, inode);
3086 inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
3087 ext4_mark_inode_dirty(handle, inode);
3088 ext4_journal_stop(handle);
3091 static void ext4_falloc_update_inode(struct inode *inode,
3092 int mode, loff_t new_size, int update_ctime)
3094 struct timespec now;
3097 now = current_fs_time(inode->i_sb);
3098 if (!timespec_equal(&inode->i_ctime, &now))
3099 inode->i_ctime = now;
3102 * Update only when preallocation was requested beyond
3105 if (!(mode & FALLOC_FL_KEEP_SIZE)) {
3106 if (new_size > i_size_read(inode))
3107 i_size_write(inode, new_size);
3108 if (new_size > EXT4_I(inode)->i_disksize)
3109 ext4_update_i_disksize(inode, new_size);
3115 * preallocate space for a file. This implements ext4's fallocate inode
3116 * operation, which gets called from sys_fallocate system call.
3117 * For block-mapped files, posix_fallocate should fall back to the method
3118 * of writing zeroes to the required new blocks (the same behavior which is
3119 * expected for file systems which do not support fallocate() system call).
3121 long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
3126 unsigned int max_blocks;
3130 struct buffer_head map_bh;
3131 unsigned int credits, blkbits = inode->i_blkbits;
3134 * currently supporting (pre)allocate mode for extent-based
3137 if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
3140 /* preallocation to directories is currently not supported */
3141 if (S_ISDIR(inode->i_mode))
3144 block = offset >> blkbits;
3146 * We can't just convert len to max_blocks because
3147 * If blocksize = 4096 offset = 3072 and len = 2048
3149 max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
3152 * credits to insert 1 extent into extent tree
3154 credits = ext4_chunk_trans_blocks(inode, max_blocks);
3155 mutex_lock(&inode->i_mutex);
3157 while (ret >= 0 && ret < max_blocks) {
3158 block = block + ret;
3159 max_blocks = max_blocks - ret;
3160 handle = ext4_journal_start(inode, credits);
3161 if (IS_ERR(handle)) {
3162 ret = PTR_ERR(handle);
3166 ret = ext4_get_blocks(handle, inode, block,
3167 max_blocks, &map_bh,
3168 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT);
3172 printk(KERN_ERR "%s: ext4_ext_get_blocks "
3173 "returned error inode#%lu, block=%u, "
3174 "max_blocks=%u", __func__,
3175 inode->i_ino, block, max_blocks);
3177 ext4_mark_inode_dirty(handle, inode);
3178 ret2 = ext4_journal_stop(handle);
3181 if ((block + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
3182 blkbits) >> blkbits))
3183 new_size = offset + len;
3185 new_size = (block + ret) << blkbits;
3187 ext4_falloc_update_inode(inode, mode, new_size,
3188 buffer_new(&map_bh));
3189 ext4_mark_inode_dirty(handle, inode);
3190 ret2 = ext4_journal_stop(handle);
3194 if (ret == -ENOSPC &&
3195 ext4_should_retry_alloc(inode->i_sb, &retries)) {
3199 mutex_unlock(&inode->i_mutex);
3200 return ret > 0 ? ret2 : ret;
3204 * Callback function called for each extent to gather FIEMAP information.
3206 static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
3207 struct ext4_ext_cache *newex, struct ext4_extent *ex,
3210 struct fiemap_extent_info *fieinfo = data;
3211 unsigned char blksize_bits = inode->i_sb->s_blocksize_bits;
3218 logical = (__u64)newex->ec_block << blksize_bits;
3220 if (newex->ec_type == EXT4_EXT_CACHE_GAP) {
3223 struct buffer_head *bh = NULL;
3225 offset = logical >> PAGE_SHIFT;
3226 page = find_get_page(inode->i_mapping, offset);
3227 if (!page || !page_has_buffers(page))
3228 return EXT_CONTINUE;
3230 bh = page_buffers(page);
3233 return EXT_CONTINUE;
3235 if (buffer_delay(bh)) {
3236 flags |= FIEMAP_EXTENT_DELALLOC;
3237 page_cache_release(page);
3239 page_cache_release(page);
3240 return EXT_CONTINUE;
3244 physical = (__u64)newex->ec_start << blksize_bits;
3245 length = (__u64)newex->ec_len << blksize_bits;
3247 if (ex && ext4_ext_is_uninitialized(ex))
3248 flags |= FIEMAP_EXTENT_UNWRITTEN;
3251 * If this extent reaches EXT_MAX_BLOCK, it must be last.
3253 * Or if ext4_ext_next_allocated_block is EXT_MAX_BLOCK,
3254 * this also indicates no more allocated blocks.
3256 * XXX this might miss a single-block extent at EXT_MAX_BLOCK
3258 if (ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK ||
3259 newex->ec_block + newex->ec_len - 1 == EXT_MAX_BLOCK) {
3260 loff_t size = i_size_read(inode);
3261 loff_t bs = EXT4_BLOCK_SIZE(inode->i_sb);
3263 flags |= FIEMAP_EXTENT_LAST;
3264 if ((flags & FIEMAP_EXTENT_DELALLOC) &&
3265 logical+length > size)
3266 length = (size - logical + bs - 1) & ~(bs-1);
3269 error = fiemap_fill_next_extent(fieinfo, logical, physical,
3276 return EXT_CONTINUE;
3279 /* fiemap flags we can handle specified here */
3280 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
3282 static int ext4_xattr_fiemap(struct inode *inode,
3283 struct fiemap_extent_info *fieinfo)
3287 __u32 flags = FIEMAP_EXTENT_LAST;
3288 int blockbits = inode->i_sb->s_blocksize_bits;
3292 if (EXT4_I(inode)->i_state & EXT4_STATE_XATTR) {
3293 struct ext4_iloc iloc;
3294 int offset; /* offset of xattr in inode */
3296 error = ext4_get_inode_loc(inode, &iloc);
3299 physical = iloc.bh->b_blocknr << blockbits;
3300 offset = EXT4_GOOD_OLD_INODE_SIZE +
3301 EXT4_I(inode)->i_extra_isize;
3303 length = EXT4_SB(inode->i_sb)->s_inode_size - offset;
3304 flags |= FIEMAP_EXTENT_DATA_INLINE;
3305 } else { /* external block */
3306 physical = EXT4_I(inode)->i_file_acl << blockbits;
3307 length = inode->i_sb->s_blocksize;
3311 error = fiemap_fill_next_extent(fieinfo, 0, physical,
3313 return (error < 0 ? error : 0);
3316 int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3317 __u64 start, __u64 len)
3319 ext4_lblk_t start_blk;
3320 ext4_lblk_t len_blks;
3323 /* fallback to generic here if not in extents fmt */
3324 if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
3325 return generic_block_fiemap(inode, fieinfo, start, len,
3328 if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
3331 if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
3332 error = ext4_xattr_fiemap(inode, fieinfo);
3334 start_blk = start >> inode->i_sb->s_blocksize_bits;
3335 len_blks = len >> inode->i_sb->s_blocksize_bits;
3338 * Walk the extent tree gathering extent information.
3339 * ext4_ext_fiemap_cb will push extents back to user.
3341 down_read(&EXT4_I(inode)->i_data_sem);
3342 error = ext4_ext_walk_space(inode, start_blk, len_blks,
3343 ext4_ext_fiemap_cb, fieinfo);
3344 up_read(&EXT4_I(inode)->i_data_sem);