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
33 #include <linux/time.h>
34 #include <linux/jbd2.h>
35 #include <linux/highuid.h>
36 #include <linux/pagemap.h>
37 #include <linux/quotaops.h>
38 #include <linux/string.h>
39 #include <linux/slab.h>
40 #include <linux/falloc.h>
41 #include <asm/uaccess.h>
42 #include <linux/fiemap.h>
43 #include "ext4_jbd2.h"
44 #include "ext4_extents.h"
47 #include <trace/events/ext4.h>
50 * used by extent splitting.
52 #define EXT4_EXT_MAY_ZEROOUT 0x1 /* safe to zeroout if split fails \
54 #define EXT4_EXT_MARK_UNINIT1 0x2 /* mark first half uninitialized */
55 #define EXT4_EXT_MARK_UNINIT2 0x4 /* mark second half uninitialized */
57 #define EXT4_EXT_DATA_VALID1 0x8 /* first half contains valid data */
58 #define EXT4_EXT_DATA_VALID2 0x10 /* second half contains valid data */
60 static __le32 ext4_extent_block_csum(struct inode *inode,
61 struct ext4_extent_header *eh)
63 struct ext4_inode_info *ei = EXT4_I(inode);
64 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
67 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)eh,
68 EXT4_EXTENT_TAIL_OFFSET(eh));
69 return cpu_to_le32(csum);
72 static int ext4_extent_block_csum_verify(struct inode *inode,
73 struct ext4_extent_header *eh)
75 struct ext4_extent_tail *et;
77 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
78 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
81 et = find_ext4_extent_tail(eh);
82 if (et->et_checksum != ext4_extent_block_csum(inode, eh))
87 static void ext4_extent_block_csum_set(struct inode *inode,
88 struct ext4_extent_header *eh)
90 struct ext4_extent_tail *et;
92 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
93 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
96 et = find_ext4_extent_tail(eh);
97 et->et_checksum = ext4_extent_block_csum(inode, eh);
100 static int ext4_split_extent(handle_t *handle,
102 struct ext4_ext_path *path,
103 struct ext4_map_blocks *map,
107 static int ext4_split_extent_at(handle_t *handle,
109 struct ext4_ext_path *path,
114 static int ext4_find_delayed_extent(struct inode *inode,
115 struct extent_status *newes);
117 static int ext4_ext_truncate_extend_restart(handle_t *handle,
123 if (!ext4_handle_valid(handle))
125 if (handle->h_buffer_credits > needed)
127 err = ext4_journal_extend(handle, needed);
130 err = ext4_truncate_restart_trans(handle, inode, needed);
142 static int ext4_ext_get_access(handle_t *handle, struct inode *inode,
143 struct ext4_ext_path *path)
146 /* path points to block */
147 return ext4_journal_get_write_access(handle, path->p_bh);
149 /* path points to leaf/index in inode body */
150 /* we use in-core data, no need to protect them */
160 int __ext4_ext_dirty(const char *where, unsigned int line, handle_t *handle,
161 struct inode *inode, struct ext4_ext_path *path)
165 ext4_extent_block_csum_set(inode, ext_block_hdr(path->p_bh));
166 /* path points to block */
167 err = __ext4_handle_dirty_metadata(where, line, handle,
170 /* path points to leaf/index in inode body */
171 err = ext4_mark_inode_dirty(handle, inode);
176 static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
177 struct ext4_ext_path *path,
181 int depth = path->p_depth;
182 struct ext4_extent *ex;
185 * Try to predict block placement assuming that we are
186 * filling in a file which will eventually be
187 * non-sparse --- i.e., in the case of libbfd writing
188 * an ELF object sections out-of-order but in a way
189 * the eventually results in a contiguous object or
190 * executable file, or some database extending a table
191 * space file. However, this is actually somewhat
192 * non-ideal if we are writing a sparse file such as
193 * qemu or KVM writing a raw image file that is going
194 * to stay fairly sparse, since it will end up
195 * fragmenting the file system's free space. Maybe we
196 * should have some hueristics or some way to allow
197 * userspace to pass a hint to file system,
198 * especially if the latter case turns out to be
201 ex = path[depth].p_ext;
203 ext4_fsblk_t ext_pblk = ext4_ext_pblock(ex);
204 ext4_lblk_t ext_block = le32_to_cpu(ex->ee_block);
206 if (block > ext_block)
207 return ext_pblk + (block - ext_block);
209 return ext_pblk - (ext_block - block);
212 /* it looks like index is empty;
213 * try to find starting block from index itself */
214 if (path[depth].p_bh)
215 return path[depth].p_bh->b_blocknr;
218 /* OK. use inode's group */
219 return ext4_inode_to_goal_block(inode);
223 * Allocation for a meta data block
226 ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,
227 struct ext4_ext_path *path,
228 struct ext4_extent *ex, int *err, unsigned int flags)
230 ext4_fsblk_t goal, newblock;
232 goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
233 newblock = ext4_new_meta_blocks(handle, inode, goal, flags,
238 static inline int ext4_ext_space_block(struct inode *inode, int check)
242 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
243 / sizeof(struct ext4_extent);
244 #ifdef AGGRESSIVE_TEST
245 if (!check && size > 6)
251 static inline int ext4_ext_space_block_idx(struct inode *inode, int check)
255 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
256 / sizeof(struct ext4_extent_idx);
257 #ifdef AGGRESSIVE_TEST
258 if (!check && size > 5)
264 static inline int ext4_ext_space_root(struct inode *inode, int check)
268 size = sizeof(EXT4_I(inode)->i_data);
269 size -= sizeof(struct ext4_extent_header);
270 size /= sizeof(struct ext4_extent);
271 #ifdef AGGRESSIVE_TEST
272 if (!check && size > 3)
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);
285 #ifdef AGGRESSIVE_TEST
286 if (!check && size > 4)
293 * Calculate the number of metadata blocks needed
294 * to allocate @blocks
295 * Worse case is one block per extent
297 int ext4_ext_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock)
299 struct ext4_inode_info *ei = EXT4_I(inode);
302 idxs = ((inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
303 / sizeof(struct ext4_extent_idx));
306 * If the new delayed allocation block is contiguous with the
307 * previous da block, it can share index blocks with the
308 * previous block, so we only need to allocate a new index
309 * block every idxs leaf blocks. At ldxs**2 blocks, we need
310 * an additional index block, and at ldxs**3 blocks, yet
311 * another index blocks.
313 if (ei->i_da_metadata_calc_len &&
314 ei->i_da_metadata_calc_last_lblock+1 == lblock) {
317 if ((ei->i_da_metadata_calc_len % idxs) == 0)
319 if ((ei->i_da_metadata_calc_len % (idxs*idxs)) == 0)
321 if ((ei->i_da_metadata_calc_len % (idxs*idxs*idxs)) == 0) {
323 ei->i_da_metadata_calc_len = 0;
325 ei->i_da_metadata_calc_len++;
326 ei->i_da_metadata_calc_last_lblock++;
331 * In the worst case we need a new set of index blocks at
332 * every level of the inode's extent tree.
334 ei->i_da_metadata_calc_len = 1;
335 ei->i_da_metadata_calc_last_lblock = lblock;
336 return ext_depth(inode) + 1;
340 ext4_ext_max_entries(struct inode *inode, int depth)
344 if (depth == ext_depth(inode)) {
346 max = ext4_ext_space_root(inode, 1);
348 max = ext4_ext_space_root_idx(inode, 1);
351 max = ext4_ext_space_block(inode, 1);
353 max = ext4_ext_space_block_idx(inode, 1);
359 static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext)
361 ext4_fsblk_t block = ext4_ext_pblock(ext);
362 int len = ext4_ext_get_actual_len(ext);
363 ext4_lblk_t lblock = le32_to_cpu(ext->ee_block);
364 ext4_lblk_t last = lblock + len - 1;
368 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
371 static int ext4_valid_extent_idx(struct inode *inode,
372 struct ext4_extent_idx *ext_idx)
374 ext4_fsblk_t block = ext4_idx_pblock(ext_idx);
376 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, 1);
379 static int ext4_valid_extent_entries(struct inode *inode,
380 struct ext4_extent_header *eh,
383 unsigned short entries;
384 if (eh->eh_entries == 0)
387 entries = le16_to_cpu(eh->eh_entries);
391 struct ext4_extent *ext = EXT_FIRST_EXTENT(eh);
392 struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
393 ext4_fsblk_t pblock = 0;
394 ext4_lblk_t lblock = 0;
395 ext4_lblk_t prev = 0;
398 if (!ext4_valid_extent(inode, ext))
401 /* Check for overlapping extents */
402 lblock = le32_to_cpu(ext->ee_block);
403 len = ext4_ext_get_actual_len(ext);
404 if ((lblock <= prev) && prev) {
405 pblock = ext4_ext_pblock(ext);
406 es->s_last_error_block = cpu_to_le64(pblock);
411 prev = lblock + len - 1;
414 struct ext4_extent_idx *ext_idx = EXT_FIRST_INDEX(eh);
416 if (!ext4_valid_extent_idx(inode, ext_idx))
425 static int __ext4_ext_check(const char *function, unsigned int line,
426 struct inode *inode, struct ext4_extent_header *eh,
429 const char *error_msg;
432 if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
433 error_msg = "invalid magic";
436 if (unlikely(le16_to_cpu(eh->eh_depth) != depth)) {
437 error_msg = "unexpected eh_depth";
440 if (unlikely(eh->eh_max == 0)) {
441 error_msg = "invalid eh_max";
444 max = ext4_ext_max_entries(inode, depth);
445 if (unlikely(le16_to_cpu(eh->eh_max) > max)) {
446 error_msg = "too large eh_max";
449 if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
450 error_msg = "invalid eh_entries";
453 if (!ext4_valid_extent_entries(inode, eh, depth)) {
454 error_msg = "invalid extent entries";
457 /* Verify checksum on non-root extent tree nodes */
458 if (ext_depth(inode) != depth &&
459 !ext4_extent_block_csum_verify(inode, eh)) {
460 error_msg = "extent tree corrupted";
466 ext4_error_inode(inode, function, line, 0,
467 "bad header/extent: %s - magic %x, "
468 "entries %u, max %u(%u), depth %u(%u)",
469 error_msg, le16_to_cpu(eh->eh_magic),
470 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
471 max, le16_to_cpu(eh->eh_depth), depth);
476 #define ext4_ext_check(inode, eh, depth) \
477 __ext4_ext_check(__func__, __LINE__, inode, eh, depth)
479 int ext4_ext_check_inode(struct inode *inode)
481 return ext4_ext_check(inode, ext_inode_hdr(inode), ext_depth(inode));
484 static int __ext4_ext_check_block(const char *function, unsigned int line,
486 struct ext4_extent_header *eh,
488 struct buffer_head *bh)
492 if (buffer_verified(bh))
494 ret = ext4_ext_check(inode, eh, depth);
497 set_buffer_verified(bh);
501 #define ext4_ext_check_block(inode, eh, depth, bh) \
502 __ext4_ext_check_block(__func__, __LINE__, inode, eh, depth, bh)
505 static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
507 int k, l = path->p_depth;
510 for (k = 0; k <= l; k++, path++) {
512 ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
513 ext4_idx_pblock(path->p_idx));
514 } else if (path->p_ext) {
515 ext_debug(" %d:[%d]%d:%llu ",
516 le32_to_cpu(path->p_ext->ee_block),
517 ext4_ext_is_uninitialized(path->p_ext),
518 ext4_ext_get_actual_len(path->p_ext),
519 ext4_ext_pblock(path->p_ext));
526 static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
528 int depth = ext_depth(inode);
529 struct ext4_extent_header *eh;
530 struct ext4_extent *ex;
536 eh = path[depth].p_hdr;
537 ex = EXT_FIRST_EXTENT(eh);
539 ext_debug("Displaying leaf extents for inode %lu\n", inode->i_ino);
541 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
542 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block),
543 ext4_ext_is_uninitialized(ex),
544 ext4_ext_get_actual_len(ex), ext4_ext_pblock(ex));
549 static void ext4_ext_show_move(struct inode *inode, struct ext4_ext_path *path,
550 ext4_fsblk_t newblock, int level)
552 int depth = ext_depth(inode);
553 struct ext4_extent *ex;
555 if (depth != level) {
556 struct ext4_extent_idx *idx;
557 idx = path[level].p_idx;
558 while (idx <= EXT_MAX_INDEX(path[level].p_hdr)) {
559 ext_debug("%d: move %d:%llu in new index %llu\n", level,
560 le32_to_cpu(idx->ei_block),
561 ext4_idx_pblock(idx),
569 ex = path[depth].p_ext;
570 while (ex <= EXT_MAX_EXTENT(path[depth].p_hdr)) {
571 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
572 le32_to_cpu(ex->ee_block),
574 ext4_ext_is_uninitialized(ex),
575 ext4_ext_get_actual_len(ex),
582 #define ext4_ext_show_path(inode, path)
583 #define ext4_ext_show_leaf(inode, path)
584 #define ext4_ext_show_move(inode, path, newblock, level)
587 void ext4_ext_drop_refs(struct ext4_ext_path *path)
589 int depth = path->p_depth;
592 for (i = 0; i <= depth; i++, path++)
600 * ext4_ext_binsearch_idx:
601 * binary search for the closest index of the given block
602 * the header must be checked before calling this
605 ext4_ext_binsearch_idx(struct inode *inode,
606 struct ext4_ext_path *path, ext4_lblk_t block)
608 struct ext4_extent_header *eh = path->p_hdr;
609 struct ext4_extent_idx *r, *l, *m;
612 ext_debug("binsearch for %u(idx): ", block);
614 l = EXT_FIRST_INDEX(eh) + 1;
615 r = EXT_LAST_INDEX(eh);
618 if (block < le32_to_cpu(m->ei_block))
622 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block),
623 m, le32_to_cpu(m->ei_block),
624 r, le32_to_cpu(r->ei_block));
628 ext_debug(" -> %u->%lld ", le32_to_cpu(path->p_idx->ei_block),
629 ext4_idx_pblock(path->p_idx));
631 #ifdef CHECK_BINSEARCH
633 struct ext4_extent_idx *chix, *ix;
636 chix = ix = EXT_FIRST_INDEX(eh);
637 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
639 le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
640 printk(KERN_DEBUG "k=%d, ix=0x%p, "
642 ix, EXT_FIRST_INDEX(eh));
643 printk(KERN_DEBUG "%u <= %u\n",
644 le32_to_cpu(ix->ei_block),
645 le32_to_cpu(ix[-1].ei_block));
647 BUG_ON(k && le32_to_cpu(ix->ei_block)
648 <= le32_to_cpu(ix[-1].ei_block));
649 if (block < le32_to_cpu(ix->ei_block))
653 BUG_ON(chix != path->p_idx);
660 * ext4_ext_binsearch:
661 * binary search for closest extent of the given block
662 * the header must be checked before calling this
665 ext4_ext_binsearch(struct inode *inode,
666 struct ext4_ext_path *path, ext4_lblk_t block)
668 struct ext4_extent_header *eh = path->p_hdr;
669 struct ext4_extent *r, *l, *m;
671 if (eh->eh_entries == 0) {
673 * this leaf is empty:
674 * we get such a leaf in split/add case
679 ext_debug("binsearch for %u: ", block);
681 l = EXT_FIRST_EXTENT(eh) + 1;
682 r = EXT_LAST_EXTENT(eh);
686 if (block < le32_to_cpu(m->ee_block))
690 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block),
691 m, le32_to_cpu(m->ee_block),
692 r, le32_to_cpu(r->ee_block));
696 ext_debug(" -> %d:%llu:[%d]%d ",
697 le32_to_cpu(path->p_ext->ee_block),
698 ext4_ext_pblock(path->p_ext),
699 ext4_ext_is_uninitialized(path->p_ext),
700 ext4_ext_get_actual_len(path->p_ext));
702 #ifdef CHECK_BINSEARCH
704 struct ext4_extent *chex, *ex;
707 chex = ex = EXT_FIRST_EXTENT(eh);
708 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
709 BUG_ON(k && le32_to_cpu(ex->ee_block)
710 <= le32_to_cpu(ex[-1].ee_block));
711 if (block < le32_to_cpu(ex->ee_block))
715 BUG_ON(chex != path->p_ext);
721 int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
723 struct ext4_extent_header *eh;
725 eh = ext_inode_hdr(inode);
728 eh->eh_magic = EXT4_EXT_MAGIC;
729 eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode, 0));
730 ext4_mark_inode_dirty(handle, inode);
734 struct ext4_ext_path *
735 ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
736 struct ext4_ext_path *path)
738 struct ext4_extent_header *eh;
739 struct buffer_head *bh;
740 short int depth, i, ppos = 0, alloc = 0;
743 eh = ext_inode_hdr(inode);
744 depth = ext_depth(inode);
746 /* account possible depth increase */
748 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 2),
751 return ERR_PTR(-ENOMEM);
758 /* walk through the tree */
760 ext_debug("depth %d: num %d, max %d\n",
761 ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
763 ext4_ext_binsearch_idx(inode, path + ppos, block);
764 path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx);
765 path[ppos].p_depth = i;
766 path[ppos].p_ext = NULL;
768 bh = sb_getblk(inode->i_sb, path[ppos].p_block);
773 if (!bh_uptodate_or_lock(bh)) {
774 trace_ext4_ext_load_extent(inode, block,
776 ret = bh_submit_read(bh);
782 eh = ext_block_hdr(bh);
784 if (unlikely(ppos > depth)) {
786 EXT4_ERROR_INODE(inode,
787 "ppos %d > depth %d", ppos, depth);
791 path[ppos].p_bh = bh;
792 path[ppos].p_hdr = eh;
795 ret = ext4_ext_check_block(inode, eh, i, bh);
800 path[ppos].p_depth = i;
801 path[ppos].p_ext = NULL;
802 path[ppos].p_idx = NULL;
805 ext4_ext_binsearch(inode, path + ppos, block);
806 /* if not an empty leaf */
807 if (path[ppos].p_ext)
808 path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext);
810 ext4_ext_show_path(inode, path);
815 ext4_ext_drop_refs(path);
822 * ext4_ext_insert_index:
823 * insert new index [@logical;@ptr] into the block at @curp;
824 * check where to insert: before @curp or after @curp
826 static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
827 struct ext4_ext_path *curp,
828 int logical, ext4_fsblk_t ptr)
830 struct ext4_extent_idx *ix;
833 err = ext4_ext_get_access(handle, inode, curp);
837 if (unlikely(logical == le32_to_cpu(curp->p_idx->ei_block))) {
838 EXT4_ERROR_INODE(inode,
839 "logical %d == ei_block %d!",
840 logical, le32_to_cpu(curp->p_idx->ei_block));
844 if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries)
845 >= le16_to_cpu(curp->p_hdr->eh_max))) {
846 EXT4_ERROR_INODE(inode,
847 "eh_entries %d >= eh_max %d!",
848 le16_to_cpu(curp->p_hdr->eh_entries),
849 le16_to_cpu(curp->p_hdr->eh_max));
853 if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
855 ext_debug("insert new index %d after: %llu\n", logical, ptr);
856 ix = curp->p_idx + 1;
859 ext_debug("insert new index %d before: %llu\n", logical, ptr);
863 len = EXT_LAST_INDEX(curp->p_hdr) - ix + 1;
866 ext_debug("insert new index %d: "
867 "move %d indices from 0x%p to 0x%p\n",
868 logical, len, ix, ix + 1);
869 memmove(ix + 1, ix, len * sizeof(struct ext4_extent_idx));
872 if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) {
873 EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!");
877 ix->ei_block = cpu_to_le32(logical);
878 ext4_idx_store_pblock(ix, ptr);
879 le16_add_cpu(&curp->p_hdr->eh_entries, 1);
881 if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) {
882 EXT4_ERROR_INODE(inode, "ix > EXT_LAST_INDEX!");
886 err = ext4_ext_dirty(handle, inode, curp);
887 ext4_std_error(inode->i_sb, err);
894 * inserts new subtree into the path, using free index entry
896 * - allocates all needed blocks (new leaf and all intermediate index blocks)
897 * - makes decision where to split
898 * - moves remaining extents and index entries (right to the split point)
899 * into the newly allocated blocks
900 * - initializes subtree
902 static int ext4_ext_split(handle_t *handle, struct inode *inode,
904 struct ext4_ext_path *path,
905 struct ext4_extent *newext, int at)
907 struct buffer_head *bh = NULL;
908 int depth = ext_depth(inode);
909 struct ext4_extent_header *neh;
910 struct ext4_extent_idx *fidx;
912 ext4_fsblk_t newblock, oldblock;
914 ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */
917 /* make decision: where to split? */
918 /* FIXME: now decision is simplest: at current extent */
920 /* if current leaf will be split, then we should use
921 * border from split point */
922 if (unlikely(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr))) {
923 EXT4_ERROR_INODE(inode, "p_ext > EXT_MAX_EXTENT!");
926 if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
927 border = path[depth].p_ext[1].ee_block;
928 ext_debug("leaf will be split."
929 " next leaf starts at %d\n",
930 le32_to_cpu(border));
932 border = newext->ee_block;
933 ext_debug("leaf will be added."
934 " next leaf starts at %d\n",
935 le32_to_cpu(border));
939 * If error occurs, then we break processing
940 * and mark filesystem read-only. index won't
941 * be inserted and tree will be in consistent
942 * state. Next mount will repair buffers too.
946 * Get array to track all allocated blocks.
947 * We need this to handle errors and free blocks
950 ablocks = kzalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS);
954 /* allocate all needed blocks */
955 ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
956 for (a = 0; a < depth - at; a++) {
957 newblock = ext4_ext_new_meta_block(handle, inode, path,
958 newext, &err, flags);
961 ablocks[a] = newblock;
964 /* initialize new leaf */
965 newblock = ablocks[--a];
966 if (unlikely(newblock == 0)) {
967 EXT4_ERROR_INODE(inode, "newblock == 0!");
971 bh = sb_getblk(inode->i_sb, newblock);
978 err = ext4_journal_get_create_access(handle, bh);
982 neh = ext_block_hdr(bh);
984 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
985 neh->eh_magic = EXT4_EXT_MAGIC;
988 /* move remainder of path[depth] to the new leaf */
989 if (unlikely(path[depth].p_hdr->eh_entries !=
990 path[depth].p_hdr->eh_max)) {
991 EXT4_ERROR_INODE(inode, "eh_entries %d != eh_max %d!",
992 path[depth].p_hdr->eh_entries,
993 path[depth].p_hdr->eh_max);
997 /* start copy from next extent */
998 m = EXT_MAX_EXTENT(path[depth].p_hdr) - path[depth].p_ext++;
999 ext4_ext_show_move(inode, path, newblock, depth);
1001 struct ext4_extent *ex;
1002 ex = EXT_FIRST_EXTENT(neh);
1003 memmove(ex, path[depth].p_ext, sizeof(struct ext4_extent) * m);
1004 le16_add_cpu(&neh->eh_entries, m);
1007 ext4_extent_block_csum_set(inode, neh);
1008 set_buffer_uptodate(bh);
1011 err = ext4_handle_dirty_metadata(handle, inode, bh);
1017 /* correct old leaf */
1019 err = ext4_ext_get_access(handle, inode, path + depth);
1022 le16_add_cpu(&path[depth].p_hdr->eh_entries, -m);
1023 err = ext4_ext_dirty(handle, inode, path + depth);
1029 /* create intermediate indexes */
1031 if (unlikely(k < 0)) {
1032 EXT4_ERROR_INODE(inode, "k %d < 0!", k);
1037 ext_debug("create %d intermediate indices\n", k);
1038 /* insert new index into current index block */
1039 /* current depth stored in i var */
1042 oldblock = newblock;
1043 newblock = ablocks[--a];
1044 bh = sb_getblk(inode->i_sb, newblock);
1045 if (unlikely(!bh)) {
1051 err = ext4_journal_get_create_access(handle, bh);
1055 neh = ext_block_hdr(bh);
1056 neh->eh_entries = cpu_to_le16(1);
1057 neh->eh_magic = EXT4_EXT_MAGIC;
1058 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
1059 neh->eh_depth = cpu_to_le16(depth - i);
1060 fidx = EXT_FIRST_INDEX(neh);
1061 fidx->ei_block = border;
1062 ext4_idx_store_pblock(fidx, oldblock);
1064 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
1065 i, newblock, le32_to_cpu(border), oldblock);
1067 /* move remainder of path[i] to the new index block */
1068 if (unlikely(EXT_MAX_INDEX(path[i].p_hdr) !=
1069 EXT_LAST_INDEX(path[i].p_hdr))) {
1070 EXT4_ERROR_INODE(inode,
1071 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
1072 le32_to_cpu(path[i].p_ext->ee_block));
1076 /* start copy indexes */
1077 m = EXT_MAX_INDEX(path[i].p_hdr) - path[i].p_idx++;
1078 ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
1079 EXT_MAX_INDEX(path[i].p_hdr));
1080 ext4_ext_show_move(inode, path, newblock, i);
1082 memmove(++fidx, path[i].p_idx,
1083 sizeof(struct ext4_extent_idx) * m);
1084 le16_add_cpu(&neh->eh_entries, m);
1086 ext4_extent_block_csum_set(inode, neh);
1087 set_buffer_uptodate(bh);
1090 err = ext4_handle_dirty_metadata(handle, inode, bh);
1096 /* correct old index */
1098 err = ext4_ext_get_access(handle, inode, path + i);
1101 le16_add_cpu(&path[i].p_hdr->eh_entries, -m);
1102 err = ext4_ext_dirty(handle, inode, path + i);
1110 /* insert new index */
1111 err = ext4_ext_insert_index(handle, inode, path + at,
1112 le32_to_cpu(border), newblock);
1116 if (buffer_locked(bh))
1122 /* free all allocated blocks in error case */
1123 for (i = 0; i < depth; i++) {
1126 ext4_free_blocks(handle, inode, NULL, ablocks[i], 1,
1127 EXT4_FREE_BLOCKS_METADATA);
1136 * ext4_ext_grow_indepth:
1137 * implements tree growing procedure:
1138 * - allocates new block
1139 * - moves top-level data (index block or leaf) into the new block
1140 * - initializes new top-level, creating index that points to the
1141 * just created block
1143 static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
1145 struct ext4_extent *newext)
1147 struct ext4_extent_header *neh;
1148 struct buffer_head *bh;
1149 ext4_fsblk_t newblock;
1152 newblock = ext4_ext_new_meta_block(handle, inode, NULL,
1153 newext, &err, flags);
1157 bh = sb_getblk(inode->i_sb, newblock);
1162 err = ext4_journal_get_create_access(handle, bh);
1168 /* move top-level index/leaf into new block */
1169 memmove(bh->b_data, EXT4_I(inode)->i_data,
1170 sizeof(EXT4_I(inode)->i_data));
1172 /* set size of new block */
1173 neh = ext_block_hdr(bh);
1174 /* old root could have indexes or leaves
1175 * so calculate e_max right way */
1176 if (ext_depth(inode))
1177 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
1179 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
1180 neh->eh_magic = EXT4_EXT_MAGIC;
1181 ext4_extent_block_csum_set(inode, neh);
1182 set_buffer_uptodate(bh);
1185 err = ext4_handle_dirty_metadata(handle, inode, bh);
1189 /* Update top-level index: num,max,pointer */
1190 neh = ext_inode_hdr(inode);
1191 neh->eh_entries = cpu_to_le16(1);
1192 ext4_idx_store_pblock(EXT_FIRST_INDEX(neh), newblock);
1193 if (neh->eh_depth == 0) {
1194 /* Root extent block becomes index block */
1195 neh->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode, 0));
1196 EXT_FIRST_INDEX(neh)->ei_block =
1197 EXT_FIRST_EXTENT(neh)->ee_block;
1199 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1200 le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
1201 le32_to_cpu(EXT_FIRST_INDEX(neh)->ei_block),
1202 ext4_idx_pblock(EXT_FIRST_INDEX(neh)));
1204 le16_add_cpu(&neh->eh_depth, 1);
1205 ext4_mark_inode_dirty(handle, inode);
1213 * ext4_ext_create_new_leaf:
1214 * finds empty index and adds new leaf.
1215 * if no free index is found, then it requests in-depth growing.
1217 static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
1219 struct ext4_ext_path *path,
1220 struct ext4_extent *newext)
1222 struct ext4_ext_path *curp;
1223 int depth, i, err = 0;
1226 i = depth = ext_depth(inode);
1228 /* walk up to the tree and look for free index entry */
1229 curp = path + depth;
1230 while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
1235 /* we use already allocated block for index block,
1236 * so subsequent data blocks should be contiguous */
1237 if (EXT_HAS_FREE_INDEX(curp)) {
1238 /* if we found index with free entry, then use that
1239 * entry: create all needed subtree and add new leaf */
1240 err = ext4_ext_split(handle, inode, flags, path, newext, i);
1245 ext4_ext_drop_refs(path);
1246 path = ext4_ext_find_extent(inode,
1247 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1250 err = PTR_ERR(path);
1252 /* tree is full, time to grow in depth */
1253 err = ext4_ext_grow_indepth(handle, inode, flags, newext);
1258 ext4_ext_drop_refs(path);
1259 path = ext4_ext_find_extent(inode,
1260 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1263 err = PTR_ERR(path);
1268 * only first (depth 0 -> 1) produces free space;
1269 * in all other cases we have to split the grown tree
1271 depth = ext_depth(inode);
1272 if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
1273 /* now we need to split */
1283 * search the closest allocated block to the left for *logical
1284 * and returns it at @logical + it's physical address at @phys
1285 * if *logical is the smallest allocated block, the function
1286 * returns 0 at @phys
1287 * return value contains 0 (success) or error code
1289 static int ext4_ext_search_left(struct inode *inode,
1290 struct ext4_ext_path *path,
1291 ext4_lblk_t *logical, ext4_fsblk_t *phys)
1293 struct ext4_extent_idx *ix;
1294 struct ext4_extent *ex;
1297 if (unlikely(path == NULL)) {
1298 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1301 depth = path->p_depth;
1304 if (depth == 0 && path->p_ext == NULL)
1307 /* usually extent in the path covers blocks smaller
1308 * then *logical, but it can be that extent is the
1309 * first one in the file */
1311 ex = path[depth].p_ext;
1312 ee_len = ext4_ext_get_actual_len(ex);
1313 if (*logical < le32_to_cpu(ex->ee_block)) {
1314 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1315 EXT4_ERROR_INODE(inode,
1316 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
1317 *logical, le32_to_cpu(ex->ee_block));
1320 while (--depth >= 0) {
1321 ix = path[depth].p_idx;
1322 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1323 EXT4_ERROR_INODE(inode,
1324 "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
1325 ix != NULL ? le32_to_cpu(ix->ei_block) : 0,
1326 EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ?
1327 le32_to_cpu(EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block) : 0,
1335 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1336 EXT4_ERROR_INODE(inode,
1337 "logical %d < ee_block %d + ee_len %d!",
1338 *logical, le32_to_cpu(ex->ee_block), ee_len);
1342 *logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
1343 *phys = ext4_ext_pblock(ex) + ee_len - 1;
1348 * search the closest allocated block to the right for *logical
1349 * and returns it at @logical + it's physical address at @phys
1350 * if *logical is the largest allocated block, the function
1351 * returns 0 at @phys
1352 * return value contains 0 (success) or error code
1354 static int ext4_ext_search_right(struct inode *inode,
1355 struct ext4_ext_path *path,
1356 ext4_lblk_t *logical, ext4_fsblk_t *phys,
1357 struct ext4_extent **ret_ex)
1359 struct buffer_head *bh = NULL;
1360 struct ext4_extent_header *eh;
1361 struct ext4_extent_idx *ix;
1362 struct ext4_extent *ex;
1364 int depth; /* Note, NOT eh_depth; depth from top of tree */
1367 if (unlikely(path == NULL)) {
1368 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1371 depth = path->p_depth;
1374 if (depth == 0 && path->p_ext == NULL)
1377 /* usually extent in the path covers blocks smaller
1378 * then *logical, but it can be that extent is the
1379 * first one in the file */
1381 ex = path[depth].p_ext;
1382 ee_len = ext4_ext_get_actual_len(ex);
1383 if (*logical < le32_to_cpu(ex->ee_block)) {
1384 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1385 EXT4_ERROR_INODE(inode,
1386 "first_extent(path[%d].p_hdr) != ex",
1390 while (--depth >= 0) {
1391 ix = path[depth].p_idx;
1392 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1393 EXT4_ERROR_INODE(inode,
1394 "ix != EXT_FIRST_INDEX *logical %d!",
1402 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1403 EXT4_ERROR_INODE(inode,
1404 "logical %d < ee_block %d + ee_len %d!",
1405 *logical, le32_to_cpu(ex->ee_block), ee_len);
1409 if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
1410 /* next allocated block in this leaf */
1415 /* go up and search for index to the right */
1416 while (--depth >= 0) {
1417 ix = path[depth].p_idx;
1418 if (ix != EXT_LAST_INDEX(path[depth].p_hdr))
1422 /* we've gone up to the root and found no index to the right */
1426 /* we've found index to the right, let's
1427 * follow it and find the closest allocated
1428 * block to the right */
1430 block = ext4_idx_pblock(ix);
1431 while (++depth < path->p_depth) {
1432 bh = sb_bread(inode->i_sb, block);
1435 eh = ext_block_hdr(bh);
1436 /* subtract from p_depth to get proper eh_depth */
1437 if (ext4_ext_check_block(inode, eh,
1438 path->p_depth - depth, bh)) {
1442 ix = EXT_FIRST_INDEX(eh);
1443 block = ext4_idx_pblock(ix);
1447 bh = sb_bread(inode->i_sb, block);
1450 eh = ext_block_hdr(bh);
1451 if (ext4_ext_check_block(inode, eh, path->p_depth - depth, bh)) {
1455 ex = EXT_FIRST_EXTENT(eh);
1457 *logical = le32_to_cpu(ex->ee_block);
1458 *phys = ext4_ext_pblock(ex);
1466 * ext4_ext_next_allocated_block:
1467 * returns allocated block in subsequent extent or EXT_MAX_BLOCKS.
1468 * NOTE: it considers block number from index entry as
1469 * allocated block. Thus, index entries have to be consistent
1473 ext4_ext_next_allocated_block(struct ext4_ext_path *path)
1477 BUG_ON(path == NULL);
1478 depth = path->p_depth;
1480 if (depth == 0 && path->p_ext == NULL)
1481 return EXT_MAX_BLOCKS;
1483 while (depth >= 0) {
1484 if (depth == path->p_depth) {
1486 if (path[depth].p_ext &&
1487 path[depth].p_ext !=
1488 EXT_LAST_EXTENT(path[depth].p_hdr))
1489 return le32_to_cpu(path[depth].p_ext[1].ee_block);
1492 if (path[depth].p_idx !=
1493 EXT_LAST_INDEX(path[depth].p_hdr))
1494 return le32_to_cpu(path[depth].p_idx[1].ei_block);
1499 return EXT_MAX_BLOCKS;
1503 * ext4_ext_next_leaf_block:
1504 * returns first allocated block from next leaf or EXT_MAX_BLOCKS
1506 static ext4_lblk_t ext4_ext_next_leaf_block(struct ext4_ext_path *path)
1510 BUG_ON(path == NULL);
1511 depth = path->p_depth;
1513 /* zero-tree has no leaf blocks at all */
1515 return EXT_MAX_BLOCKS;
1517 /* go to index block */
1520 while (depth >= 0) {
1521 if (path[depth].p_idx !=
1522 EXT_LAST_INDEX(path[depth].p_hdr))
1523 return (ext4_lblk_t)
1524 le32_to_cpu(path[depth].p_idx[1].ei_block);
1528 return EXT_MAX_BLOCKS;
1532 * ext4_ext_correct_indexes:
1533 * if leaf gets modified and modified extent is first in the leaf,
1534 * then we have to correct all indexes above.
1535 * TODO: do we need to correct tree in all cases?
1537 static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
1538 struct ext4_ext_path *path)
1540 struct ext4_extent_header *eh;
1541 int depth = ext_depth(inode);
1542 struct ext4_extent *ex;
1546 eh = path[depth].p_hdr;
1547 ex = path[depth].p_ext;
1549 if (unlikely(ex == NULL || eh == NULL)) {
1550 EXT4_ERROR_INODE(inode,
1551 "ex %p == NULL or eh %p == NULL", ex, eh);
1556 /* there is no tree at all */
1560 if (ex != EXT_FIRST_EXTENT(eh)) {
1561 /* we correct tree if first leaf got modified only */
1566 * TODO: we need correction if border is smaller than current one
1569 border = path[depth].p_ext->ee_block;
1570 err = ext4_ext_get_access(handle, inode, path + k);
1573 path[k].p_idx->ei_block = border;
1574 err = ext4_ext_dirty(handle, inode, path + k);
1579 /* change all left-side indexes */
1580 if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
1582 err = ext4_ext_get_access(handle, inode, path + k);
1585 path[k].p_idx->ei_block = border;
1586 err = ext4_ext_dirty(handle, inode, path + k);
1595 ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
1596 struct ext4_extent *ex2)
1598 unsigned short ext1_ee_len, ext2_ee_len, max_len;
1601 * Make sure that both extents are initialized. We don't merge
1602 * uninitialized extents so that we can be sure that end_io code has
1603 * the extent that was written properly split out and conversion to
1604 * initialized is trivial.
1606 if (ext4_ext_is_uninitialized(ex1) || ext4_ext_is_uninitialized(ex2))
1609 if (ext4_ext_is_uninitialized(ex1))
1610 max_len = EXT_UNINIT_MAX_LEN;
1612 max_len = EXT_INIT_MAX_LEN;
1614 ext1_ee_len = ext4_ext_get_actual_len(ex1);
1615 ext2_ee_len = ext4_ext_get_actual_len(ex2);
1617 if (le32_to_cpu(ex1->ee_block) + ext1_ee_len !=
1618 le32_to_cpu(ex2->ee_block))
1622 * To allow future support for preallocated extents to be added
1623 * as an RO_COMPAT feature, refuse to merge to extents if
1624 * this can result in the top bit of ee_len being set.
1626 if (ext1_ee_len + ext2_ee_len > max_len)
1628 #ifdef AGGRESSIVE_TEST
1629 if (ext1_ee_len >= 4)
1633 if (ext4_ext_pblock(ex1) + ext1_ee_len == ext4_ext_pblock(ex2))
1639 * This function tries to merge the "ex" extent to the next extent in the tree.
1640 * It always tries to merge towards right. If you want to merge towards
1641 * left, pass "ex - 1" as argument instead of "ex".
1642 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1643 * 1 if they got merged.
1645 static int ext4_ext_try_to_merge_right(struct inode *inode,
1646 struct ext4_ext_path *path,
1647 struct ext4_extent *ex)
1649 struct ext4_extent_header *eh;
1650 unsigned int depth, len;
1652 int uninitialized = 0;
1654 depth = ext_depth(inode);
1655 BUG_ON(path[depth].p_hdr == NULL);
1656 eh = path[depth].p_hdr;
1658 while (ex < EXT_LAST_EXTENT(eh)) {
1659 if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
1661 /* merge with next extent! */
1662 if (ext4_ext_is_uninitialized(ex))
1664 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1665 + ext4_ext_get_actual_len(ex + 1));
1667 ext4_ext_mark_uninitialized(ex);
1669 if (ex + 1 < EXT_LAST_EXTENT(eh)) {
1670 len = (EXT_LAST_EXTENT(eh) - ex - 1)
1671 * sizeof(struct ext4_extent);
1672 memmove(ex + 1, ex + 2, len);
1674 le16_add_cpu(&eh->eh_entries, -1);
1676 WARN_ON(eh->eh_entries == 0);
1677 if (!eh->eh_entries)
1678 EXT4_ERROR_INODE(inode, "eh->eh_entries = 0!");
1685 * This function does a very simple check to see if we can collapse
1686 * an extent tree with a single extent tree leaf block into the inode.
1688 static void ext4_ext_try_to_merge_up(handle_t *handle,
1689 struct inode *inode,
1690 struct ext4_ext_path *path)
1693 unsigned max_root = ext4_ext_space_root(inode, 0);
1696 if ((path[0].p_depth != 1) ||
1697 (le16_to_cpu(path[0].p_hdr->eh_entries) != 1) ||
1698 (le16_to_cpu(path[1].p_hdr->eh_entries) > max_root))
1702 * We need to modify the block allocation bitmap and the block
1703 * group descriptor to release the extent tree block. If we
1704 * can't get the journal credits, give up.
1706 if (ext4_journal_extend(handle, 2))
1710 * Copy the extent data up to the inode
1712 blk = ext4_idx_pblock(path[0].p_idx);
1713 s = le16_to_cpu(path[1].p_hdr->eh_entries) *
1714 sizeof(struct ext4_extent_idx);
1715 s += sizeof(struct ext4_extent_header);
1717 memcpy(path[0].p_hdr, path[1].p_hdr, s);
1718 path[0].p_depth = 0;
1719 path[0].p_ext = EXT_FIRST_EXTENT(path[0].p_hdr) +
1720 (path[1].p_ext - EXT_FIRST_EXTENT(path[1].p_hdr));
1721 path[0].p_hdr->eh_max = cpu_to_le16(max_root);
1723 brelse(path[1].p_bh);
1724 ext4_free_blocks(handle, inode, NULL, blk, 1,
1725 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
1729 * This function tries to merge the @ex extent to neighbours in the tree.
1730 * return 1 if merge left else 0.
1732 static void ext4_ext_try_to_merge(handle_t *handle,
1733 struct inode *inode,
1734 struct ext4_ext_path *path,
1735 struct ext4_extent *ex) {
1736 struct ext4_extent_header *eh;
1740 depth = ext_depth(inode);
1741 BUG_ON(path[depth].p_hdr == NULL);
1742 eh = path[depth].p_hdr;
1744 if (ex > EXT_FIRST_EXTENT(eh))
1745 merge_done = ext4_ext_try_to_merge_right(inode, path, ex - 1);
1748 (void) ext4_ext_try_to_merge_right(inode, path, ex);
1750 ext4_ext_try_to_merge_up(handle, inode, path);
1754 * check if a portion of the "newext" extent overlaps with an
1757 * If there is an overlap discovered, it updates the length of the newext
1758 * such that there will be no overlap, and then returns 1.
1759 * If there is no overlap found, it returns 0.
1761 static unsigned int ext4_ext_check_overlap(struct ext4_sb_info *sbi,
1762 struct inode *inode,
1763 struct ext4_extent *newext,
1764 struct ext4_ext_path *path)
1767 unsigned int depth, len1;
1768 unsigned int ret = 0;
1770 b1 = le32_to_cpu(newext->ee_block);
1771 len1 = ext4_ext_get_actual_len(newext);
1772 depth = ext_depth(inode);
1773 if (!path[depth].p_ext)
1775 b2 = EXT4_LBLK_CMASK(sbi, le32_to_cpu(path[depth].p_ext->ee_block));
1778 * get the next allocated block if the extent in the path
1779 * is before the requested block(s)
1782 b2 = ext4_ext_next_allocated_block(path);
1783 if (b2 == EXT_MAX_BLOCKS)
1785 b2 = EXT4_LBLK_CMASK(sbi, b2);
1788 /* check for wrap through zero on extent logical start block*/
1789 if (b1 + len1 < b1) {
1790 len1 = EXT_MAX_BLOCKS - b1;
1791 newext->ee_len = cpu_to_le16(len1);
1795 /* check for overlap */
1796 if (b1 + len1 > b2) {
1797 newext->ee_len = cpu_to_le16(b2 - b1);
1805 * ext4_ext_insert_extent:
1806 * tries to merge requsted extent into the existing extent or
1807 * inserts requested extent as new one into the tree,
1808 * creating new leaf in the no-space case.
1810 int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
1811 struct ext4_ext_path *path,
1812 struct ext4_extent *newext, int flag)
1814 struct ext4_extent_header *eh;
1815 struct ext4_extent *ex, *fex;
1816 struct ext4_extent *nearex; /* nearest extent */
1817 struct ext4_ext_path *npath = NULL;
1818 int depth, len, err;
1820 unsigned uninitialized = 0;
1823 if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
1824 EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
1827 depth = ext_depth(inode);
1828 ex = path[depth].p_ext;
1829 eh = path[depth].p_hdr;
1830 if (unlikely(path[depth].p_hdr == NULL)) {
1831 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
1835 /* try to insert block into found extent and return */
1836 if (ex && !(flag & EXT4_GET_BLOCKS_PRE_IO)) {
1839 * Try to see whether we should rather test the extent on
1840 * right from ex, or from the left of ex. This is because
1841 * ext4_ext_find_extent() can return either extent on the
1842 * left, or on the right from the searched position. This
1843 * will make merging more effective.
1845 if (ex < EXT_LAST_EXTENT(eh) &&
1846 (le32_to_cpu(ex->ee_block) +
1847 ext4_ext_get_actual_len(ex) <
1848 le32_to_cpu(newext->ee_block))) {
1851 } else if ((ex > EXT_FIRST_EXTENT(eh)) &&
1852 (le32_to_cpu(newext->ee_block) +
1853 ext4_ext_get_actual_len(newext) <
1854 le32_to_cpu(ex->ee_block)))
1857 /* Try to append newex to the ex */
1858 if (ext4_can_extents_be_merged(inode, ex, newext)) {
1859 ext_debug("append [%d]%d block to %u:[%d]%d"
1861 ext4_ext_is_uninitialized(newext),
1862 ext4_ext_get_actual_len(newext),
1863 le32_to_cpu(ex->ee_block),
1864 ext4_ext_is_uninitialized(ex),
1865 ext4_ext_get_actual_len(ex),
1866 ext4_ext_pblock(ex));
1867 err = ext4_ext_get_access(handle, inode,
1873 * ext4_can_extents_be_merged should have checked
1874 * that either both extents are uninitialized, or
1875 * both aren't. Thus we need to check only one of
1878 if (ext4_ext_is_uninitialized(ex))
1880 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1881 + ext4_ext_get_actual_len(newext));
1883 ext4_ext_mark_uninitialized(ex);
1884 eh = path[depth].p_hdr;
1890 /* Try to prepend newex to the ex */
1891 if (ext4_can_extents_be_merged(inode, newext, ex)) {
1892 ext_debug("prepend %u[%d]%d block to %u:[%d]%d"
1894 le32_to_cpu(newext->ee_block),
1895 ext4_ext_is_uninitialized(newext),
1896 ext4_ext_get_actual_len(newext),
1897 le32_to_cpu(ex->ee_block),
1898 ext4_ext_is_uninitialized(ex),
1899 ext4_ext_get_actual_len(ex),
1900 ext4_ext_pblock(ex));
1901 err = ext4_ext_get_access(handle, inode,
1907 * ext4_can_extents_be_merged should have checked
1908 * that either both extents are uninitialized, or
1909 * both aren't. Thus we need to check only one of
1912 if (ext4_ext_is_uninitialized(ex))
1914 ex->ee_block = newext->ee_block;
1915 ext4_ext_store_pblock(ex, ext4_ext_pblock(newext));
1916 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1917 + ext4_ext_get_actual_len(newext));
1919 ext4_ext_mark_uninitialized(ex);
1920 eh = path[depth].p_hdr;
1926 depth = ext_depth(inode);
1927 eh = path[depth].p_hdr;
1928 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
1931 /* probably next leaf has space for us? */
1932 fex = EXT_LAST_EXTENT(eh);
1933 next = EXT_MAX_BLOCKS;
1934 if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block))
1935 next = ext4_ext_next_leaf_block(path);
1936 if (next != EXT_MAX_BLOCKS) {
1937 ext_debug("next leaf block - %u\n", next);
1938 BUG_ON(npath != NULL);
1939 npath = ext4_ext_find_extent(inode, next, NULL);
1941 return PTR_ERR(npath);
1942 BUG_ON(npath->p_depth != path->p_depth);
1943 eh = npath[depth].p_hdr;
1944 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
1945 ext_debug("next leaf isn't full(%d)\n",
1946 le16_to_cpu(eh->eh_entries));
1950 ext_debug("next leaf has no free space(%d,%d)\n",
1951 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
1955 * There is no free space in the found leaf.
1956 * We're gonna add a new leaf in the tree.
1958 if (flag & EXT4_GET_BLOCKS_METADATA_NOFAIL)
1959 flags = EXT4_MB_USE_RESERVED;
1960 err = ext4_ext_create_new_leaf(handle, inode, flags, path, newext);
1963 depth = ext_depth(inode);
1964 eh = path[depth].p_hdr;
1967 nearex = path[depth].p_ext;
1969 err = ext4_ext_get_access(handle, inode, path + depth);
1974 /* there is no extent in this leaf, create first one */
1975 ext_debug("first extent in the leaf: %u:%llu:[%d]%d\n",
1976 le32_to_cpu(newext->ee_block),
1977 ext4_ext_pblock(newext),
1978 ext4_ext_is_uninitialized(newext),
1979 ext4_ext_get_actual_len(newext));
1980 nearex = EXT_FIRST_EXTENT(eh);
1982 if (le32_to_cpu(newext->ee_block)
1983 > le32_to_cpu(nearex->ee_block)) {
1985 ext_debug("insert %u:%llu:[%d]%d before: "
1987 le32_to_cpu(newext->ee_block),
1988 ext4_ext_pblock(newext),
1989 ext4_ext_is_uninitialized(newext),
1990 ext4_ext_get_actual_len(newext),
1995 BUG_ON(newext->ee_block == nearex->ee_block);
1996 ext_debug("insert %u:%llu:[%d]%d after: "
1998 le32_to_cpu(newext->ee_block),
1999 ext4_ext_pblock(newext),
2000 ext4_ext_is_uninitialized(newext),
2001 ext4_ext_get_actual_len(newext),
2004 len = EXT_LAST_EXTENT(eh) - nearex + 1;
2006 ext_debug("insert %u:%llu:[%d]%d: "
2007 "move %d extents from 0x%p to 0x%p\n",
2008 le32_to_cpu(newext->ee_block),
2009 ext4_ext_pblock(newext),
2010 ext4_ext_is_uninitialized(newext),
2011 ext4_ext_get_actual_len(newext),
2012 len, nearex, nearex + 1);
2013 memmove(nearex + 1, nearex,
2014 len * sizeof(struct ext4_extent));
2018 le16_add_cpu(&eh->eh_entries, 1);
2019 path[depth].p_ext = nearex;
2020 nearex->ee_block = newext->ee_block;
2021 ext4_ext_store_pblock(nearex, ext4_ext_pblock(newext));
2022 nearex->ee_len = newext->ee_len;
2025 /* try to merge extents */
2026 if (!(flag & EXT4_GET_BLOCKS_PRE_IO))
2027 ext4_ext_try_to_merge(handle, inode, path, nearex);
2030 /* time to correct all indexes above */
2031 err = ext4_ext_correct_indexes(handle, inode, path);
2035 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
2039 ext4_ext_drop_refs(npath);
2045 static int ext4_fill_fiemap_extents(struct inode *inode,
2046 ext4_lblk_t block, ext4_lblk_t num,
2047 struct fiemap_extent_info *fieinfo)
2049 struct ext4_ext_path *path = NULL;
2050 struct ext4_extent *ex;
2051 struct extent_status es;
2052 ext4_lblk_t next, next_del, start = 0, end = 0;
2053 ext4_lblk_t last = block + num;
2054 int exists, depth = 0, err = 0;
2055 unsigned int flags = 0;
2056 unsigned char blksize_bits = inode->i_sb->s_blocksize_bits;
2058 while (block < last && block != EXT_MAX_BLOCKS) {
2060 /* find extent for this block */
2061 down_read(&EXT4_I(inode)->i_data_sem);
2063 if (path && ext_depth(inode) != depth) {
2064 /* depth was changed. we have to realloc path */
2069 path = ext4_ext_find_extent(inode, block, path);
2071 up_read(&EXT4_I(inode)->i_data_sem);
2072 err = PTR_ERR(path);
2077 depth = ext_depth(inode);
2078 if (unlikely(path[depth].p_hdr == NULL)) {
2079 up_read(&EXT4_I(inode)->i_data_sem);
2080 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
2084 ex = path[depth].p_ext;
2085 next = ext4_ext_next_allocated_block(path);
2086 ext4_ext_drop_refs(path);
2091 /* there is no extent yet, so try to allocate
2092 * all requested space */
2095 } else if (le32_to_cpu(ex->ee_block) > block) {
2096 /* need to allocate space before found extent */
2098 end = le32_to_cpu(ex->ee_block);
2099 if (block + num < end)
2101 } else if (block >= le32_to_cpu(ex->ee_block)
2102 + ext4_ext_get_actual_len(ex)) {
2103 /* need to allocate space after found extent */
2108 } else if (block >= le32_to_cpu(ex->ee_block)) {
2110 * some part of requested space is covered
2114 end = le32_to_cpu(ex->ee_block)
2115 + ext4_ext_get_actual_len(ex);
2116 if (block + num < end)
2122 BUG_ON(end <= start);
2126 es.es_len = end - start;
2129 es.es_lblk = le32_to_cpu(ex->ee_block);
2130 es.es_len = ext4_ext_get_actual_len(ex);
2131 es.es_pblk = ext4_ext_pblock(ex);
2132 if (ext4_ext_is_uninitialized(ex))
2133 flags |= FIEMAP_EXTENT_UNWRITTEN;
2137 * Find delayed extent and update es accordingly. We call
2138 * it even in !exists case to find out whether es is the
2139 * last existing extent or not.
2141 next_del = ext4_find_delayed_extent(inode, &es);
2142 if (!exists && next_del) {
2144 flags |= FIEMAP_EXTENT_DELALLOC;
2146 up_read(&EXT4_I(inode)->i_data_sem);
2148 if (unlikely(es.es_len == 0)) {
2149 EXT4_ERROR_INODE(inode, "es.es_len == 0");
2155 * This is possible iff next == next_del == EXT_MAX_BLOCKS.
2156 * we need to check next == EXT_MAX_BLOCKS because it is
2157 * possible that an extent is with unwritten and delayed
2158 * status due to when an extent is delayed allocated and
2159 * is allocated by fallocate status tree will track both of
2162 * So we could return a unwritten and delayed extent, and
2163 * its block is equal to 'next'.
2165 if (next == next_del && next == EXT_MAX_BLOCKS) {
2166 flags |= FIEMAP_EXTENT_LAST;
2167 if (unlikely(next_del != EXT_MAX_BLOCKS ||
2168 next != EXT_MAX_BLOCKS)) {
2169 EXT4_ERROR_INODE(inode,
2170 "next extent == %u, next "
2171 "delalloc extent = %u",
2179 err = fiemap_fill_next_extent(fieinfo,
2180 (__u64)es.es_lblk << blksize_bits,
2181 (__u64)es.es_pblk << blksize_bits,
2182 (__u64)es.es_len << blksize_bits,
2192 block = es.es_lblk + es.es_len;
2196 ext4_ext_drop_refs(path);
2204 * ext4_ext_put_gap_in_cache:
2205 * calculate boundaries of the gap that the requested block fits into
2206 * and cache this gap
2209 ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
2212 int depth = ext_depth(inode);
2215 struct ext4_extent *ex;
2217 ex = path[depth].p_ext;
2220 * there is no extent yet, so gap is [0;-] and we
2223 ext_debug("cache gap(whole file):");
2224 } else if (block < le32_to_cpu(ex->ee_block)) {
2226 len = le32_to_cpu(ex->ee_block) - block;
2227 ext_debug("cache gap(before): %u [%u:%u]",
2229 le32_to_cpu(ex->ee_block),
2230 ext4_ext_get_actual_len(ex));
2231 if (!ext4_find_delalloc_range(inode, lblock, lblock + len - 1))
2232 ext4_es_insert_extent(inode, lblock, len, ~0,
2233 EXTENT_STATUS_HOLE);
2234 } else if (block >= le32_to_cpu(ex->ee_block)
2235 + ext4_ext_get_actual_len(ex)) {
2237 lblock = le32_to_cpu(ex->ee_block)
2238 + ext4_ext_get_actual_len(ex);
2240 next = ext4_ext_next_allocated_block(path);
2241 ext_debug("cache gap(after): [%u:%u] %u",
2242 le32_to_cpu(ex->ee_block),
2243 ext4_ext_get_actual_len(ex),
2245 BUG_ON(next == lblock);
2246 len = next - lblock;
2247 if (!ext4_find_delalloc_range(inode, lblock, lblock + len - 1))
2248 ext4_es_insert_extent(inode, lblock, len, ~0,
2249 EXTENT_STATUS_HOLE);
2255 ext_debug(" -> %u:%lu\n", lblock, len);
2260 * removes index from the index block.
2262 static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
2263 struct ext4_ext_path *path, int depth)
2268 /* free index block */
2270 path = path + depth;
2271 leaf = ext4_idx_pblock(path->p_idx);
2272 if (unlikely(path->p_hdr->eh_entries == 0)) {
2273 EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0");
2276 err = ext4_ext_get_access(handle, inode, path);
2280 if (path->p_idx != EXT_LAST_INDEX(path->p_hdr)) {
2281 int len = EXT_LAST_INDEX(path->p_hdr) - path->p_idx;
2282 len *= sizeof(struct ext4_extent_idx);
2283 memmove(path->p_idx, path->p_idx + 1, len);
2286 le16_add_cpu(&path->p_hdr->eh_entries, -1);
2287 err = ext4_ext_dirty(handle, inode, path);
2290 ext_debug("index is empty, remove it, free block %llu\n", leaf);
2291 trace_ext4_ext_rm_idx(inode, leaf);
2293 ext4_free_blocks(handle, inode, NULL, leaf, 1,
2294 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
2296 while (--depth >= 0) {
2297 if (path->p_idx != EXT_FIRST_INDEX(path->p_hdr))
2300 err = ext4_ext_get_access(handle, inode, path);
2303 path->p_idx->ei_block = (path+1)->p_idx->ei_block;
2304 err = ext4_ext_dirty(handle, inode, path);
2312 * ext4_ext_calc_credits_for_single_extent:
2313 * This routine returns max. credits that needed to insert an extent
2314 * to the extent tree.
2315 * When pass the actual path, the caller should calculate credits
2318 int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks,
2319 struct ext4_ext_path *path)
2322 int depth = ext_depth(inode);
2325 /* probably there is space in leaf? */
2326 if (le16_to_cpu(path[depth].p_hdr->eh_entries)
2327 < le16_to_cpu(path[depth].p_hdr->eh_max)) {
2330 * There are some space in the leaf tree, no
2331 * need to account for leaf block credit
2333 * bitmaps and block group descriptor blocks
2334 * and other metadata blocks still need to be
2337 /* 1 bitmap, 1 block group descriptor */
2338 ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb);
2343 return ext4_chunk_trans_blocks(inode, nrblocks);
2347 * How many index/leaf blocks need to change/allocate to modify nrblocks?
2349 * if nrblocks are fit in a single extent (chunk flag is 1), then
2350 * in the worse case, each tree level index/leaf need to be changed
2351 * if the tree split due to insert a new extent, then the old tree
2352 * index/leaf need to be updated too
2354 * If the nrblocks are discontiguous, they could cause
2355 * the whole tree split more than once, but this is really rare.
2357 int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
2362 /* If we are converting the inline data, only one is needed here. */
2363 if (ext4_has_inline_data(inode))
2366 depth = ext_depth(inode);
2376 static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
2377 struct ext4_extent *ex,
2378 ext4_fsblk_t *partial_cluster,
2379 ext4_lblk_t from, ext4_lblk_t to)
2381 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2382 unsigned short ee_len = ext4_ext_get_actual_len(ex);
2386 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2387 flags |= EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET;
2388 else if (ext4_should_journal_data(inode))
2389 flags |= EXT4_FREE_BLOCKS_FORGET;
2392 * For bigalloc file systems, we never free a partial cluster
2393 * at the beginning of the extent. Instead, we make a note
2394 * that we tried freeing the cluster, and check to see if we
2395 * need to free it on a subsequent call to ext4_remove_blocks,
2396 * or at the end of the ext4_truncate() operation.
2398 flags |= EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER;
2400 trace_ext4_remove_blocks(inode, ex, from, to, *partial_cluster);
2402 * If we have a partial cluster, and it's different from the
2403 * cluster of the last block, we need to explicitly free the
2404 * partial cluster here.
2406 pblk = ext4_ext_pblock(ex) + ee_len - 1;
2407 if (*partial_cluster && (EXT4_B2C(sbi, pblk) != *partial_cluster)) {
2408 ext4_free_blocks(handle, inode, NULL,
2409 EXT4_C2B(sbi, *partial_cluster),
2410 sbi->s_cluster_ratio, flags);
2411 *partial_cluster = 0;
2414 #ifdef EXTENTS_STATS
2416 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2417 spin_lock(&sbi->s_ext_stats_lock);
2418 sbi->s_ext_blocks += ee_len;
2419 sbi->s_ext_extents++;
2420 if (ee_len < sbi->s_ext_min)
2421 sbi->s_ext_min = ee_len;
2422 if (ee_len > sbi->s_ext_max)
2423 sbi->s_ext_max = ee_len;
2424 if (ext_depth(inode) > sbi->s_depth_max)
2425 sbi->s_depth_max = ext_depth(inode);
2426 spin_unlock(&sbi->s_ext_stats_lock);
2429 if (from >= le32_to_cpu(ex->ee_block)
2430 && to == le32_to_cpu(ex->ee_block) + ee_len - 1) {
2434 num = le32_to_cpu(ex->ee_block) + ee_len - from;
2435 pblk = ext4_ext_pblock(ex) + ee_len - num;
2436 ext_debug("free last %u blocks starting %llu\n", num, pblk);
2437 ext4_free_blocks(handle, inode, NULL, pblk, num, flags);
2439 * If the block range to be freed didn't start at the
2440 * beginning of a cluster, and we removed the entire
2441 * extent, save the partial cluster here, since we
2442 * might need to delete if we determine that the
2443 * truncate operation has removed all of the blocks in
2446 if (EXT4_PBLK_COFF(sbi, pblk) &&
2448 *partial_cluster = EXT4_B2C(sbi, pblk);
2450 *partial_cluster = 0;
2451 } else if (from == le32_to_cpu(ex->ee_block)
2452 && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
2458 start = ext4_ext_pblock(ex);
2460 ext_debug("free first %u blocks starting %llu\n", num, start);
2461 ext4_free_blocks(handle, inode, NULL, start, num, flags);
2464 printk(KERN_INFO "strange request: removal(2) "
2465 "%u-%u from %u:%u\n",
2466 from, to, le32_to_cpu(ex->ee_block), ee_len);
2473 * ext4_ext_rm_leaf() Removes the extents associated with the
2474 * blocks appearing between "start" and "end", and splits the extents
2475 * if "start" and "end" appear in the same extent
2477 * @handle: The journal handle
2478 * @inode: The files inode
2479 * @path: The path to the leaf
2480 * @start: The first block to remove
2481 * @end: The last block to remove
2484 ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
2485 struct ext4_ext_path *path, ext4_fsblk_t *partial_cluster,
2486 ext4_lblk_t start, ext4_lblk_t end)
2488 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2489 int err = 0, correct_index = 0;
2490 int depth = ext_depth(inode), credits;
2491 struct ext4_extent_header *eh;
2494 ext4_lblk_t ex_ee_block;
2495 unsigned short ex_ee_len;
2496 unsigned uninitialized = 0;
2497 struct ext4_extent *ex;
2499 /* the header must be checked already in ext4_ext_remove_space() */
2500 ext_debug("truncate since %u in leaf to %u\n", start, end);
2501 if (!path[depth].p_hdr)
2502 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
2503 eh = path[depth].p_hdr;
2504 if (unlikely(path[depth].p_hdr == NULL)) {
2505 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
2508 /* find where to start removing */
2509 ex = EXT_LAST_EXTENT(eh);
2511 ex_ee_block = le32_to_cpu(ex->ee_block);
2512 ex_ee_len = ext4_ext_get_actual_len(ex);
2515 * If we're starting with an extent other than the last one in the
2516 * node, we need to see if it shares a cluster with the extent to
2517 * the right (towards the end of the file). If its leftmost cluster
2518 * is this extent's rightmost cluster and it is not cluster aligned,
2519 * we'll mark it as a partial that is not to be deallocated.
2522 if (ex != EXT_LAST_EXTENT(eh)) {
2523 ext4_fsblk_t current_pblk, right_pblk;
2524 long long current_cluster, right_cluster;
2526 current_pblk = ext4_ext_pblock(ex) + ex_ee_len - 1;
2527 current_cluster = (long long)EXT4_B2C(sbi, current_pblk);
2528 right_pblk = ext4_ext_pblock(ex + 1);
2529 right_cluster = (long long)EXT4_B2C(sbi, right_pblk);
2530 if (current_cluster == right_cluster &&
2531 EXT4_PBLK_COFF(sbi, right_pblk))
2532 *partial_cluster = -right_cluster;
2535 trace_ext4_ext_rm_leaf(inode, start, ex, *partial_cluster);
2537 while (ex >= EXT_FIRST_EXTENT(eh) &&
2538 ex_ee_block + ex_ee_len > start) {
2540 if (ext4_ext_is_uninitialized(ex))
2545 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block,
2546 uninitialized, ex_ee_len);
2547 path[depth].p_ext = ex;
2549 a = ex_ee_block > start ? ex_ee_block : start;
2550 b = ex_ee_block+ex_ee_len - 1 < end ?
2551 ex_ee_block+ex_ee_len - 1 : end;
2553 ext_debug(" border %u:%u\n", a, b);
2555 /* If this extent is beyond the end of the hole, skip it */
2556 if (end < ex_ee_block) {
2558 ex_ee_block = le32_to_cpu(ex->ee_block);
2559 ex_ee_len = ext4_ext_get_actual_len(ex);
2561 } else if (b != ex_ee_block + ex_ee_len - 1) {
2562 EXT4_ERROR_INODE(inode,
2563 "can not handle truncate %u:%u "
2565 start, end, ex_ee_block,
2566 ex_ee_block + ex_ee_len - 1);
2569 } else if (a != ex_ee_block) {
2570 /* remove tail of the extent */
2571 num = a - ex_ee_block;
2573 /* remove whole extent: excellent! */
2577 * 3 for leaf, sb, and inode plus 2 (bmap and group
2578 * descriptor) for each block group; assume two block
2579 * groups plus ex_ee_len/blocks_per_block_group for
2582 credits = 7 + 2*(ex_ee_len/EXT4_BLOCKS_PER_GROUP(inode->i_sb));
2583 if (ex == EXT_FIRST_EXTENT(eh)) {
2585 credits += (ext_depth(inode)) + 1;
2587 credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
2589 err = ext4_ext_truncate_extend_restart(handle, inode, credits);
2593 err = ext4_ext_get_access(handle, inode, path + depth);
2597 err = ext4_remove_blocks(handle, inode, ex, partial_cluster,
2603 /* this extent is removed; mark slot entirely unused */
2604 ext4_ext_store_pblock(ex, 0);
2606 ex->ee_len = cpu_to_le16(num);
2608 * Do not mark uninitialized if all the blocks in the
2609 * extent have been removed.
2611 if (uninitialized && num)
2612 ext4_ext_mark_uninitialized(ex);
2614 * If the extent was completely released,
2615 * we need to remove it from the leaf
2618 if (end != EXT_MAX_BLOCKS - 1) {
2620 * For hole punching, we need to scoot all the
2621 * extents up when an extent is removed so that
2622 * we dont have blank extents in the middle
2624 memmove(ex, ex+1, (EXT_LAST_EXTENT(eh) - ex) *
2625 sizeof(struct ext4_extent));
2627 /* Now get rid of the one at the end */
2628 memset(EXT_LAST_EXTENT(eh), 0,
2629 sizeof(struct ext4_extent));
2631 le16_add_cpu(&eh->eh_entries, -1);
2633 *partial_cluster = 0;
2635 err = ext4_ext_dirty(handle, inode, path + depth);
2639 ext_debug("new extent: %u:%u:%llu\n", ex_ee_block, num,
2640 ext4_ext_pblock(ex));
2642 ex_ee_block = le32_to_cpu(ex->ee_block);
2643 ex_ee_len = ext4_ext_get_actual_len(ex);
2646 if (correct_index && eh->eh_entries)
2647 err = ext4_ext_correct_indexes(handle, inode, path);
2650 * If there is still a entry in the leaf node, check to see if
2651 * it references the partial cluster. This is the only place
2652 * where it could; if it doesn't, we can free the cluster.
2654 if (*partial_cluster && ex >= EXT_FIRST_EXTENT(eh) &&
2655 (EXT4_B2C(sbi, ext4_ext_pblock(ex) + ex_ee_len - 1) !=
2656 *partial_cluster)) {
2657 int flags = EXT4_FREE_BLOCKS_FORGET;
2659 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2660 flags |= EXT4_FREE_BLOCKS_METADATA;
2662 ext4_free_blocks(handle, inode, NULL,
2663 EXT4_C2B(sbi, *partial_cluster),
2664 sbi->s_cluster_ratio, flags);
2665 *partial_cluster = 0;
2668 /* if this leaf is free, then we should
2669 * remove it from index block above */
2670 if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
2671 err = ext4_ext_rm_idx(handle, inode, path, depth);
2678 * ext4_ext_more_to_rm:
2679 * returns 1 if current index has to be freed (even partial)
2682 ext4_ext_more_to_rm(struct ext4_ext_path *path)
2684 BUG_ON(path->p_idx == NULL);
2686 if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
2690 * if truncate on deeper level happened, it wasn't partial,
2691 * so we have to consider current index for truncation
2693 if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
2698 int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2701 struct super_block *sb = inode->i_sb;
2702 int depth = ext_depth(inode);
2703 struct ext4_ext_path *path = NULL;
2704 ext4_fsblk_t partial_cluster = 0;
2708 ext_debug("truncate since %u to %u\n", start, end);
2710 /* probably first extent we're gonna free will be last in block */
2711 handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, depth + 1);
2713 return PTR_ERR(handle);
2716 trace_ext4_ext_remove_space(inode, start, depth);
2719 * Check if we are removing extents inside the extent tree. If that
2720 * is the case, we are going to punch a hole inside the extent tree
2721 * so we have to check whether we need to split the extent covering
2722 * the last block to remove so we can easily remove the part of it
2723 * in ext4_ext_rm_leaf().
2725 if (end < EXT_MAX_BLOCKS - 1) {
2726 struct ext4_extent *ex;
2727 ext4_lblk_t ee_block;
2729 /* find extent for this block */
2730 path = ext4_ext_find_extent(inode, end, NULL);
2732 ext4_journal_stop(handle);
2733 return PTR_ERR(path);
2735 depth = ext_depth(inode);
2736 /* Leaf not may not exist only if inode has no blocks at all */
2737 ex = path[depth].p_ext;
2740 EXT4_ERROR_INODE(inode,
2741 "path[%d].p_hdr == NULL",
2748 ee_block = le32_to_cpu(ex->ee_block);
2751 * See if the last block is inside the extent, if so split
2752 * the extent at 'end' block so we can easily remove the
2753 * tail of the first part of the split extent in
2754 * ext4_ext_rm_leaf().
2756 if (end >= ee_block &&
2757 end < ee_block + ext4_ext_get_actual_len(ex) - 1) {
2760 if (ext4_ext_is_uninitialized(ex))
2761 split_flag = EXT4_EXT_MARK_UNINIT1 |
2762 EXT4_EXT_MARK_UNINIT2;
2765 * Split the extent in two so that 'end' is the last
2766 * block in the first new extent. Also we should not
2767 * fail removing space due to ENOSPC so try to use
2768 * reserved block if that happens.
2770 err = ext4_split_extent_at(handle, inode, path,
2771 end + 1, split_flag,
2772 EXT4_GET_BLOCKS_PRE_IO |
2773 EXT4_GET_BLOCKS_METADATA_NOFAIL);
2780 * We start scanning from right side, freeing all the blocks
2781 * after i_size and walking into the tree depth-wise.
2783 depth = ext_depth(inode);
2788 le16_to_cpu(path[k].p_hdr->eh_entries)+1;
2790 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1),
2793 ext4_journal_stop(handle);
2796 path[0].p_depth = depth;
2797 path[0].p_hdr = ext_inode_hdr(inode);
2800 if (ext4_ext_check(inode, path[0].p_hdr, depth)) {
2807 while (i >= 0 && err == 0) {
2809 /* this is leaf block */
2810 err = ext4_ext_rm_leaf(handle, inode, path,
2811 &partial_cluster, start,
2813 /* root level has p_bh == NULL, brelse() eats this */
2814 brelse(path[i].p_bh);
2815 path[i].p_bh = NULL;
2820 /* this is index block */
2821 if (!path[i].p_hdr) {
2822 ext_debug("initialize header\n");
2823 path[i].p_hdr = ext_block_hdr(path[i].p_bh);
2826 if (!path[i].p_idx) {
2827 /* this level hasn't been touched yet */
2828 path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
2829 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
2830 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2832 le16_to_cpu(path[i].p_hdr->eh_entries));
2834 /* we were already here, see at next index */
2838 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2839 i, EXT_FIRST_INDEX(path[i].p_hdr),
2841 if (ext4_ext_more_to_rm(path + i)) {
2842 struct buffer_head *bh;
2843 /* go to the next level */
2844 ext_debug("move to level %d (block %llu)\n",
2845 i + 1, ext4_idx_pblock(path[i].p_idx));
2846 memset(path + i + 1, 0, sizeof(*path));
2847 bh = sb_bread(sb, ext4_idx_pblock(path[i].p_idx));
2849 /* should we reset i_size? */
2853 if (WARN_ON(i + 1 > depth)) {
2857 if (ext4_ext_check_block(inode, ext_block_hdr(bh),
2858 depth - i - 1, bh)) {
2862 path[i + 1].p_bh = bh;
2864 /* save actual number of indexes since this
2865 * number is changed at the next iteration */
2866 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
2869 /* we finished processing this index, go up */
2870 if (path[i].p_hdr->eh_entries == 0 && i > 0) {
2871 /* index is empty, remove it;
2872 * handle must be already prepared by the
2873 * truncatei_leaf() */
2874 err = ext4_ext_rm_idx(handle, inode, path, i);
2876 /* root level has p_bh == NULL, brelse() eats this */
2877 brelse(path[i].p_bh);
2878 path[i].p_bh = NULL;
2880 ext_debug("return to level %d\n", i);
2884 trace_ext4_ext_remove_space_done(inode, start, depth, partial_cluster,
2885 path->p_hdr->eh_entries);
2887 /* If we still have something in the partial cluster and we have removed
2888 * even the first extent, then we should free the blocks in the partial
2889 * cluster as well. */
2890 if (partial_cluster && path->p_hdr->eh_entries == 0) {
2891 int flags = EXT4_FREE_BLOCKS_FORGET;
2893 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2894 flags |= EXT4_FREE_BLOCKS_METADATA;
2896 ext4_free_blocks(handle, inode, NULL,
2897 EXT4_C2B(EXT4_SB(sb), partial_cluster),
2898 EXT4_SB(sb)->s_cluster_ratio, flags);
2899 partial_cluster = 0;
2902 /* TODO: flexible tree reduction should be here */
2903 if (path->p_hdr->eh_entries == 0) {
2905 * truncate to zero freed all the tree,
2906 * so we need to correct eh_depth
2908 err = ext4_ext_get_access(handle, inode, path);
2910 ext_inode_hdr(inode)->eh_depth = 0;
2911 ext_inode_hdr(inode)->eh_max =
2912 cpu_to_le16(ext4_ext_space_root(inode, 0));
2913 err = ext4_ext_dirty(handle, inode, path);
2917 ext4_ext_drop_refs(path);
2919 if (err == -EAGAIN) {
2923 ext4_journal_stop(handle);
2929 * called at mount time
2931 void ext4_ext_init(struct super_block *sb)
2934 * possible initialization would be here
2937 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2938 #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
2939 printk(KERN_INFO "EXT4-fs: file extents enabled"
2940 #ifdef AGGRESSIVE_TEST
2941 ", aggressive tests"
2943 #ifdef CHECK_BINSEARCH
2946 #ifdef EXTENTS_STATS
2951 #ifdef EXTENTS_STATS
2952 spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
2953 EXT4_SB(sb)->s_ext_min = 1 << 30;
2954 EXT4_SB(sb)->s_ext_max = 0;
2960 * called at umount time
2962 void ext4_ext_release(struct super_block *sb)
2964 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2967 #ifdef EXTENTS_STATS
2968 if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
2969 struct ext4_sb_info *sbi = EXT4_SB(sb);
2970 printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2971 sbi->s_ext_blocks, sbi->s_ext_extents,
2972 sbi->s_ext_blocks / sbi->s_ext_extents);
2973 printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2974 sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
2979 /* FIXME!! we need to try to merge to left or right after zero-out */
2980 static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
2982 ext4_fsblk_t ee_pblock;
2983 unsigned int ee_len;
2986 ee_len = ext4_ext_get_actual_len(ex);
2987 ee_pblock = ext4_ext_pblock(ex);
2989 ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
2997 * ext4_split_extent_at() splits an extent at given block.
2999 * @handle: the journal handle
3000 * @inode: the file inode
3001 * @path: the path to the extent
3002 * @split: the logical block where the extent is splitted.
3003 * @split_flags: indicates if the extent could be zeroout if split fails, and
3004 * the states(init or uninit) of new extents.
3005 * @flags: flags used to insert new extent to extent tree.
3008 * Splits extent [a, b] into two extents [a, @split) and [@split, b], states
3009 * of which are deterimined by split_flag.
3011 * There are two cases:
3012 * a> the extent are splitted into two extent.
3013 * b> split is not needed, and just mark the extent.
3015 * return 0 on success.
3017 static int ext4_split_extent_at(handle_t *handle,
3018 struct inode *inode,
3019 struct ext4_ext_path *path,
3024 ext4_fsblk_t newblock;
3025 ext4_lblk_t ee_block;
3026 struct ext4_extent *ex, newex, orig_ex, zero_ex;
3027 struct ext4_extent *ex2 = NULL;
3028 unsigned int ee_len, depth;
3031 BUG_ON((split_flag & (EXT4_EXT_DATA_VALID1 | EXT4_EXT_DATA_VALID2)) ==
3032 (EXT4_EXT_DATA_VALID1 | EXT4_EXT_DATA_VALID2));
3034 ext_debug("ext4_split_extents_at: inode %lu, logical"
3035 "block %llu\n", inode->i_ino, (unsigned long long)split);
3037 ext4_ext_show_leaf(inode, path);
3039 depth = ext_depth(inode);
3040 ex = path[depth].p_ext;
3041 ee_block = le32_to_cpu(ex->ee_block);
3042 ee_len = ext4_ext_get_actual_len(ex);
3043 newblock = split - ee_block + ext4_ext_pblock(ex);
3045 BUG_ON(split < ee_block || split >= (ee_block + ee_len));
3046 BUG_ON(!ext4_ext_is_uninitialized(ex) &&
3047 split_flag & (EXT4_EXT_MAY_ZEROOUT |
3048 EXT4_EXT_MARK_UNINIT1 |
3049 EXT4_EXT_MARK_UNINIT2));
3051 err = ext4_ext_get_access(handle, inode, path + depth);
3055 if (split == ee_block) {
3057 * case b: block @split is the block that the extent begins with
3058 * then we just change the state of the extent, and splitting
3061 if (split_flag & EXT4_EXT_MARK_UNINIT2)
3062 ext4_ext_mark_uninitialized(ex);
3064 ext4_ext_mark_initialized(ex);
3066 if (!(flags & EXT4_GET_BLOCKS_PRE_IO))
3067 ext4_ext_try_to_merge(handle, inode, path, ex);
3069 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
3074 memcpy(&orig_ex, ex, sizeof(orig_ex));
3075 ex->ee_len = cpu_to_le16(split - ee_block);
3076 if (split_flag & EXT4_EXT_MARK_UNINIT1)
3077 ext4_ext_mark_uninitialized(ex);
3080 * path may lead to new leaf, not to original leaf any more
3081 * after ext4_ext_insert_extent() returns,
3083 err = ext4_ext_dirty(handle, inode, path + depth);
3085 goto fix_extent_len;
3088 ex2->ee_block = cpu_to_le32(split);
3089 ex2->ee_len = cpu_to_le16(ee_len - (split - ee_block));
3090 ext4_ext_store_pblock(ex2, newblock);
3091 if (split_flag & EXT4_EXT_MARK_UNINIT2)
3092 ext4_ext_mark_uninitialized(ex2);
3094 err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
3095 if (err == -ENOSPC && (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
3096 if (split_flag & (EXT4_EXT_DATA_VALID1|EXT4_EXT_DATA_VALID2)) {
3097 if (split_flag & EXT4_EXT_DATA_VALID1) {
3098 err = ext4_ext_zeroout(inode, ex2);
3099 zero_ex.ee_block = ex2->ee_block;
3100 zero_ex.ee_len = cpu_to_le16(
3101 ext4_ext_get_actual_len(ex2));
3102 ext4_ext_store_pblock(&zero_ex,
3103 ext4_ext_pblock(ex2));
3105 err = ext4_ext_zeroout(inode, ex);
3106 zero_ex.ee_block = ex->ee_block;
3107 zero_ex.ee_len = cpu_to_le16(
3108 ext4_ext_get_actual_len(ex));
3109 ext4_ext_store_pblock(&zero_ex,
3110 ext4_ext_pblock(ex));
3113 err = ext4_ext_zeroout(inode, &orig_ex);
3114 zero_ex.ee_block = orig_ex.ee_block;
3115 zero_ex.ee_len = cpu_to_le16(
3116 ext4_ext_get_actual_len(&orig_ex));
3117 ext4_ext_store_pblock(&zero_ex,
3118 ext4_ext_pblock(&orig_ex));
3122 goto fix_extent_len;
3123 /* update the extent length and mark as initialized */
3124 ex->ee_len = cpu_to_le16(ee_len);
3125 ext4_ext_try_to_merge(handle, inode, path, ex);
3126 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
3128 goto fix_extent_len;
3130 /* update extent status tree */
3131 err = ext4_es_zeroout(inode, &zero_ex);
3135 goto fix_extent_len;
3138 ext4_ext_show_leaf(inode, path);
3142 ex->ee_len = orig_ex.ee_len;
3143 ext4_ext_dirty(handle, inode, path + depth);
3148 * ext4_split_extents() splits an extent and mark extent which is covered
3149 * by @map as split_flags indicates
3151 * It may result in splitting the extent into multiple extents (upto three)
3152 * There are three possibilities:
3153 * a> There is no split required
3154 * b> Splits in two extents: Split is happening at either end of the extent
3155 * c> Splits in three extents: Somone is splitting in middle of the extent
3158 static int ext4_split_extent(handle_t *handle,
3159 struct inode *inode,
3160 struct ext4_ext_path *path,
3161 struct ext4_map_blocks *map,
3165 ext4_lblk_t ee_block;
3166 struct ext4_extent *ex;
3167 unsigned int ee_len, depth;
3170 int split_flag1, flags1;
3171 int allocated = map->m_len;
3173 depth = ext_depth(inode);
3174 ex = path[depth].p_ext;
3175 ee_block = le32_to_cpu(ex->ee_block);
3176 ee_len = ext4_ext_get_actual_len(ex);
3177 uninitialized = ext4_ext_is_uninitialized(ex);
3179 if (map->m_lblk + map->m_len < ee_block + ee_len) {
3180 split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT;
3181 flags1 = flags | EXT4_GET_BLOCKS_PRE_IO;
3183 split_flag1 |= EXT4_EXT_MARK_UNINIT1 |
3184 EXT4_EXT_MARK_UNINIT2;
3185 if (split_flag & EXT4_EXT_DATA_VALID2)
3186 split_flag1 |= EXT4_EXT_DATA_VALID1;
3187 err = ext4_split_extent_at(handle, inode, path,
3188 map->m_lblk + map->m_len, split_flag1, flags1);
3192 allocated = ee_len - (map->m_lblk - ee_block);
3195 * Update path is required because previous ext4_split_extent_at() may
3196 * result in split of original leaf or extent zeroout.
3198 ext4_ext_drop_refs(path);
3199 path = ext4_ext_find_extent(inode, map->m_lblk, path);
3201 return PTR_ERR(path);
3202 depth = ext_depth(inode);
3203 ex = path[depth].p_ext;
3204 uninitialized = ext4_ext_is_uninitialized(ex);
3207 if (map->m_lblk >= ee_block) {
3208 split_flag1 = split_flag & EXT4_EXT_DATA_VALID2;
3209 if (uninitialized) {
3210 split_flag1 |= EXT4_EXT_MARK_UNINIT1;
3211 split_flag1 |= split_flag & (EXT4_EXT_MAY_ZEROOUT |
3212 EXT4_EXT_MARK_UNINIT2);
3214 err = ext4_split_extent_at(handle, inode, path,
3215 map->m_lblk, split_flag1, flags);
3220 ext4_ext_show_leaf(inode, path);
3222 return err ? err : allocated;
3226 * This function is called by ext4_ext_map_blocks() if someone tries to write
3227 * to an uninitialized extent. It may result in splitting the uninitialized
3228 * extent into multiple extents (up to three - one initialized and two
3230 * There are three possibilities:
3231 * a> There is no split required: Entire extent should be initialized
3232 * b> Splits in two extents: Write is happening at either end of the extent
3233 * c> Splits in three extents: Somone is writing in middle of the extent
3236 * - The extent pointed to by 'path' is uninitialized.
3237 * - The extent pointed to by 'path' contains a superset
3238 * of the logical span [map->m_lblk, map->m_lblk + map->m_len).
3240 * Post-conditions on success:
3241 * - the returned value is the number of blocks beyond map->l_lblk
3242 * that are allocated and initialized.
3243 * It is guaranteed to be >= map->m_len.
3245 static int ext4_ext_convert_to_initialized(handle_t *handle,
3246 struct inode *inode,
3247 struct ext4_map_blocks *map,
3248 struct ext4_ext_path *path,
3251 struct ext4_sb_info *sbi;
3252 struct ext4_extent_header *eh;
3253 struct ext4_map_blocks split_map;
3254 struct ext4_extent zero_ex;
3255 struct ext4_extent *ex, *abut_ex;
3256 ext4_lblk_t ee_block, eof_block;
3257 unsigned int ee_len, depth, map_len = map->m_len;
3258 int allocated = 0, max_zeroout = 0;
3262 ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
3263 "block %llu, max_blocks %u\n", inode->i_ino,
3264 (unsigned long long)map->m_lblk, map_len);
3266 sbi = EXT4_SB(inode->i_sb);
3267 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
3268 inode->i_sb->s_blocksize_bits;
3269 if (eof_block < map->m_lblk + map_len)
3270 eof_block = map->m_lblk + map_len;
3272 depth = ext_depth(inode);
3273 eh = path[depth].p_hdr;
3274 ex = path[depth].p_ext;
3275 ee_block = le32_to_cpu(ex->ee_block);
3276 ee_len = ext4_ext_get_actual_len(ex);
3279 trace_ext4_ext_convert_to_initialized_enter(inode, map, ex);
3281 /* Pre-conditions */
3282 BUG_ON(!ext4_ext_is_uninitialized(ex));
3283 BUG_ON(!in_range(map->m_lblk, ee_block, ee_len));
3286 * Attempt to transfer newly initialized blocks from the currently
3287 * uninitialized extent to its neighbor. This is much cheaper
3288 * than an insertion followed by a merge as those involve costly
3289 * memmove() calls. Transferring to the left is the common case in
3290 * steady state for workloads doing fallocate(FALLOC_FL_KEEP_SIZE)
3291 * followed by append writes.
3293 * Limitations of the current logic:
3294 * - L1: we do not deal with writes covering the whole extent.
3295 * This would require removing the extent if the transfer
3297 * - L2: we only attempt to merge with an extent stored in the
3298 * same extent tree node.
3300 if ((map->m_lblk == ee_block) &&
3301 /* See if we can merge left */
3302 (map_len < ee_len) && /*L1*/
3303 (ex > EXT_FIRST_EXTENT(eh))) { /*L2*/
3304 ext4_lblk_t prev_lblk;
3305 ext4_fsblk_t prev_pblk, ee_pblk;
3306 unsigned int prev_len;
3309 prev_lblk = le32_to_cpu(abut_ex->ee_block);
3310 prev_len = ext4_ext_get_actual_len(abut_ex);
3311 prev_pblk = ext4_ext_pblock(abut_ex);
3312 ee_pblk = ext4_ext_pblock(ex);
3315 * A transfer of blocks from 'ex' to 'abut_ex' is allowed
3316 * upon those conditions:
3317 * - C1: abut_ex is initialized,
3318 * - C2: abut_ex is logically abutting ex,
3319 * - C3: abut_ex is physically abutting ex,
3320 * - C4: abut_ex can receive the additional blocks without
3321 * overflowing the (initialized) length limit.
3323 if ((!ext4_ext_is_uninitialized(abut_ex)) && /*C1*/
3324 ((prev_lblk + prev_len) == ee_block) && /*C2*/
3325 ((prev_pblk + prev_len) == ee_pblk) && /*C3*/
3326 (prev_len < (EXT_INIT_MAX_LEN - map_len))) { /*C4*/
3327 err = ext4_ext_get_access(handle, inode, path + depth);
3331 trace_ext4_ext_convert_to_initialized_fastpath(inode,
3334 /* Shift the start of ex by 'map_len' blocks */
3335 ex->ee_block = cpu_to_le32(ee_block + map_len);
3336 ext4_ext_store_pblock(ex, ee_pblk + map_len);
3337 ex->ee_len = cpu_to_le16(ee_len - map_len);
3338 ext4_ext_mark_uninitialized(ex); /* Restore the flag */
3340 /* Extend abut_ex by 'map_len' blocks */
3341 abut_ex->ee_len = cpu_to_le16(prev_len + map_len);
3343 /* Result: number of initialized blocks past m_lblk */
3344 allocated = map_len;
3346 } else if (((map->m_lblk + map_len) == (ee_block + ee_len)) &&
3347 (map_len < ee_len) && /*L1*/
3348 ex < EXT_LAST_EXTENT(eh)) { /*L2*/
3349 /* See if we can merge right */
3350 ext4_lblk_t next_lblk;
3351 ext4_fsblk_t next_pblk, ee_pblk;
3352 unsigned int next_len;
3355 next_lblk = le32_to_cpu(abut_ex->ee_block);
3356 next_len = ext4_ext_get_actual_len(abut_ex);
3357 next_pblk = ext4_ext_pblock(abut_ex);
3358 ee_pblk = ext4_ext_pblock(ex);
3361 * A transfer of blocks from 'ex' to 'abut_ex' is allowed
3362 * upon those conditions:
3363 * - C1: abut_ex is initialized,
3364 * - C2: abut_ex is logically abutting ex,
3365 * - C3: abut_ex is physically abutting ex,
3366 * - C4: abut_ex can receive the additional blocks without
3367 * overflowing the (initialized) length limit.
3369 if ((!ext4_ext_is_uninitialized(abut_ex)) && /*C1*/
3370 ((map->m_lblk + map_len) == next_lblk) && /*C2*/
3371 ((ee_pblk + ee_len) == next_pblk) && /*C3*/
3372 (next_len < (EXT_INIT_MAX_LEN - map_len))) { /*C4*/
3373 err = ext4_ext_get_access(handle, inode, path + depth);
3377 trace_ext4_ext_convert_to_initialized_fastpath(inode,
3380 /* Shift the start of abut_ex by 'map_len' blocks */
3381 abut_ex->ee_block = cpu_to_le32(next_lblk - map_len);
3382 ext4_ext_store_pblock(abut_ex, next_pblk - map_len);
3383 ex->ee_len = cpu_to_le16(ee_len - map_len);
3384 ext4_ext_mark_uninitialized(ex); /* Restore the flag */
3386 /* Extend abut_ex by 'map_len' blocks */
3387 abut_ex->ee_len = cpu_to_le16(next_len + map_len);
3389 /* Result: number of initialized blocks past m_lblk */
3390 allocated = map_len;
3394 /* Mark the block containing both extents as dirty */
3395 ext4_ext_dirty(handle, inode, path + depth);
3397 /* Update path to point to the right extent */
3398 path[depth].p_ext = abut_ex;
3401 allocated = ee_len - (map->m_lblk - ee_block);
3403 WARN_ON(map->m_lblk < ee_block);
3405 * It is safe to convert extent to initialized via explicit
3406 * zeroout only if extent is fully insde i_size or new_size.
3408 split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
3410 if (EXT4_EXT_MAY_ZEROOUT & split_flag)
3411 max_zeroout = sbi->s_extent_max_zeroout_kb >>
3412 (inode->i_sb->s_blocksize_bits - 10);
3414 /* If extent is less than s_max_zeroout_kb, zeroout directly */
3415 if (max_zeroout && (ee_len <= max_zeroout)) {
3416 err = ext4_ext_zeroout(inode, ex);
3419 zero_ex.ee_block = ex->ee_block;
3420 zero_ex.ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex));
3421 ext4_ext_store_pblock(&zero_ex, ext4_ext_pblock(ex));
3423 err = ext4_ext_get_access(handle, inode, path + depth);
3426 ext4_ext_mark_initialized(ex);
3427 ext4_ext_try_to_merge(handle, inode, path, ex);
3428 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
3434 * 1. split the extent into three extents.
3435 * 2. split the extent into two extents, zeroout the first half.
3436 * 3. split the extent into two extents, zeroout the second half.
3437 * 4. split the extent into two extents with out zeroout.
3439 split_map.m_lblk = map->m_lblk;
3440 split_map.m_len = map->m_len;
3442 if (max_zeroout && (allocated > map->m_len)) {
3443 if (allocated <= max_zeroout) {
3446 cpu_to_le32(map->m_lblk);
3447 zero_ex.ee_len = cpu_to_le16(allocated);
3448 ext4_ext_store_pblock(&zero_ex,
3449 ext4_ext_pblock(ex) + map->m_lblk - ee_block);
3450 err = ext4_ext_zeroout(inode, &zero_ex);
3453 split_map.m_lblk = map->m_lblk;
3454 split_map.m_len = allocated;
3455 } else if (map->m_lblk - ee_block + map->m_len < max_zeroout) {
3457 if (map->m_lblk != ee_block) {
3458 zero_ex.ee_block = ex->ee_block;
3459 zero_ex.ee_len = cpu_to_le16(map->m_lblk -
3461 ext4_ext_store_pblock(&zero_ex,
3462 ext4_ext_pblock(ex));
3463 err = ext4_ext_zeroout(inode, &zero_ex);
3468 split_map.m_lblk = ee_block;
3469 split_map.m_len = map->m_lblk - ee_block + map->m_len;
3470 allocated = map->m_len;
3474 allocated = ext4_split_extent(handle, inode, path,
3475 &split_map, split_flag, flags);
3480 /* If we have gotten a failure, don't zero out status tree */
3482 err = ext4_es_zeroout(inode, &zero_ex);
3483 return err ? err : allocated;
3487 * This function is called by ext4_ext_map_blocks() from
3488 * ext4_get_blocks_dio_write() when DIO to write
3489 * to an uninitialized extent.
3491 * Writing to an uninitialized extent may result in splitting the uninitialized
3492 * extent into multiple initialized/uninitialized extents (up to three)
3493 * There are three possibilities:
3494 * a> There is no split required: Entire extent should be uninitialized
3495 * b> Splits in two extents: Write is happening at either end of the extent
3496 * c> Splits in three extents: Somone is writing in middle of the extent
3498 * One of more index blocks maybe needed if the extent tree grow after
3499 * the uninitialized extent split. To prevent ENOSPC occur at the IO
3500 * complete, we need to split the uninitialized extent before DIO submit
3501 * the IO. The uninitialized extent called at this time will be split
3502 * into three uninitialized extent(at most). After IO complete, the part
3503 * being filled will be convert to initialized by the end_io callback function
3504 * via ext4_convert_unwritten_extents().
3506 * Returns the size of uninitialized extent to be written on success.
3508 static int ext4_split_unwritten_extents(handle_t *handle,
3509 struct inode *inode,
3510 struct ext4_map_blocks *map,
3511 struct ext4_ext_path *path,
3514 ext4_lblk_t eof_block;
3515 ext4_lblk_t ee_block;
3516 struct ext4_extent *ex;
3517 unsigned int ee_len;
3518 int split_flag = 0, depth;
3520 ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
3521 "block %llu, max_blocks %u\n", inode->i_ino,
3522 (unsigned long long)map->m_lblk, map->m_len);
3524 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
3525 inode->i_sb->s_blocksize_bits;
3526 if (eof_block < map->m_lblk + map->m_len)
3527 eof_block = map->m_lblk + map->m_len;
3529 * It is safe to convert extent to initialized via explicit
3530 * zeroout only if extent is fully insde i_size or new_size.
3532 depth = ext_depth(inode);
3533 ex = path[depth].p_ext;
3534 ee_block = le32_to_cpu(ex->ee_block);
3535 ee_len = ext4_ext_get_actual_len(ex);
3537 split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
3538 split_flag |= EXT4_EXT_MARK_UNINIT2;
3539 if (flags & EXT4_GET_BLOCKS_CONVERT)
3540 split_flag |= EXT4_EXT_DATA_VALID2;
3541 flags |= EXT4_GET_BLOCKS_PRE_IO;
3542 return ext4_split_extent(handle, inode, path, map, split_flag, flags);
3545 static int ext4_convert_unwritten_extents_endio(handle_t *handle,
3546 struct inode *inode,
3547 struct ext4_map_blocks *map,
3548 struct ext4_ext_path *path)
3550 struct ext4_extent *ex;
3551 ext4_lblk_t ee_block;
3552 unsigned int ee_len;
3556 depth = ext_depth(inode);
3557 ex = path[depth].p_ext;
3558 ee_block = le32_to_cpu(ex->ee_block);
3559 ee_len = ext4_ext_get_actual_len(ex);
3561 ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical"
3562 "block %llu, max_blocks %u\n", inode->i_ino,
3563 (unsigned long long)ee_block, ee_len);
3565 /* If extent is larger than requested it is a clear sign that we still
3566 * have some extent state machine issues left. So extent_split is still
3568 * TODO: Once all related issues will be fixed this situation should be
3571 if (ee_block != map->m_lblk || ee_len > map->m_len) {
3573 ext4_warning("Inode (%ld) finished: extent logical block %llu,"
3574 " len %u; IO logical block %llu, len %u\n",
3575 inode->i_ino, (unsigned long long)ee_block, ee_len,
3576 (unsigned long long)map->m_lblk, map->m_len);
3578 err = ext4_split_unwritten_extents(handle, inode, map, path,
3579 EXT4_GET_BLOCKS_CONVERT);
3582 ext4_ext_drop_refs(path);
3583 path = ext4_ext_find_extent(inode, map->m_lblk, path);
3585 err = PTR_ERR(path);
3588 depth = ext_depth(inode);
3589 ex = path[depth].p_ext;
3592 err = ext4_ext_get_access(handle, inode, path + depth);
3595 /* first mark the extent as initialized */
3596 ext4_ext_mark_initialized(ex);
3598 /* note: ext4_ext_correct_indexes() isn't needed here because
3599 * borders are not changed
3601 ext4_ext_try_to_merge(handle, inode, path, ex);
3603 /* Mark modified extent as dirty */
3604 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
3606 ext4_ext_show_leaf(inode, path);
3610 static void unmap_underlying_metadata_blocks(struct block_device *bdev,
3611 sector_t block, int count)
3614 for (i = 0; i < count; i++)
3615 unmap_underlying_metadata(bdev, block + i);
3619 * Handle EOFBLOCKS_FL flag, clearing it if necessary
3621 static int check_eofblocks_fl(handle_t *handle, struct inode *inode,
3623 struct ext4_ext_path *path,
3627 struct ext4_extent_header *eh;
3628 struct ext4_extent *last_ex;
3630 if (!ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
3633 depth = ext_depth(inode);
3634 eh = path[depth].p_hdr;
3637 * We're going to remove EOFBLOCKS_FL entirely in future so we
3638 * do not care for this case anymore. Simply remove the flag
3639 * if there are no extents.
3641 if (unlikely(!eh->eh_entries))
3643 last_ex = EXT_LAST_EXTENT(eh);
3645 * We should clear the EOFBLOCKS_FL flag if we are writing the
3646 * last block in the last extent in the file. We test this by
3647 * first checking to see if the caller to
3648 * ext4_ext_get_blocks() was interested in the last block (or
3649 * a block beyond the last block) in the current extent. If
3650 * this turns out to be false, we can bail out from this
3651 * function immediately.
3653 if (lblk + len < le32_to_cpu(last_ex->ee_block) +
3654 ext4_ext_get_actual_len(last_ex))
3657 * If the caller does appear to be planning to write at or
3658 * beyond the end of the current extent, we then test to see
3659 * if the current extent is the last extent in the file, by
3660 * checking to make sure it was reached via the rightmost node
3661 * at each level of the tree.
3663 for (i = depth-1; i >= 0; i--)
3664 if (path[i].p_idx != EXT_LAST_INDEX(path[i].p_hdr))
3667 ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
3668 return ext4_mark_inode_dirty(handle, inode);
3672 * ext4_find_delalloc_range: find delayed allocated block in the given range.
3674 * Return 1 if there is a delalloc block in the range, otherwise 0.
3676 int ext4_find_delalloc_range(struct inode *inode,
3677 ext4_lblk_t lblk_start,
3678 ext4_lblk_t lblk_end)
3680 struct extent_status es;
3682 ext4_es_find_delayed_extent_range(inode, lblk_start, lblk_end, &es);
3684 return 0; /* there is no delay extent in this tree */
3685 else if (es.es_lblk <= lblk_start &&
3686 lblk_start < es.es_lblk + es.es_len)
3688 else if (lblk_start <= es.es_lblk && es.es_lblk <= lblk_end)
3694 int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk)
3696 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3697 ext4_lblk_t lblk_start, lblk_end;
3698 lblk_start = EXT4_LBLK_CMASK(sbi, lblk);
3699 lblk_end = lblk_start + sbi->s_cluster_ratio - 1;
3701 return ext4_find_delalloc_range(inode, lblk_start, lblk_end);
3705 * Determines how many complete clusters (out of those specified by the 'map')
3706 * are under delalloc and were reserved quota for.
3707 * This function is called when we are writing out the blocks that were
3708 * originally written with their allocation delayed, but then the space was
3709 * allocated using fallocate() before the delayed allocation could be resolved.
3710 * The cases to look for are:
3711 * ('=' indicated delayed allocated blocks
3712 * '-' indicates non-delayed allocated blocks)
3713 * (a) partial clusters towards beginning and/or end outside of allocated range
3714 * are not delalloc'ed.
3716 * |----c---=|====c====|====c====|===-c----|
3717 * |++++++ allocated ++++++|
3718 * ==> 4 complete clusters in above example
3720 * (b) partial cluster (outside of allocated range) towards either end is
3721 * marked for delayed allocation. In this case, we will exclude that
3724 * |----====c========|========c========|
3725 * |++++++ allocated ++++++|
3726 * ==> 1 complete clusters in above example
3729 * |================c================|
3730 * |++++++ allocated ++++++|
3731 * ==> 0 complete clusters in above example
3733 * The ext4_da_update_reserve_space will be called only if we
3734 * determine here that there were some "entire" clusters that span
3735 * this 'allocated' range.
3736 * In the non-bigalloc case, this function will just end up returning num_blks
3737 * without ever calling ext4_find_delalloc_range.
3740 get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start,
3741 unsigned int num_blks)
3743 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3744 ext4_lblk_t alloc_cluster_start, alloc_cluster_end;
3745 ext4_lblk_t lblk_from, lblk_to, c_offset;
3746 unsigned int allocated_clusters = 0;
3748 alloc_cluster_start = EXT4_B2C(sbi, lblk_start);
3749 alloc_cluster_end = EXT4_B2C(sbi, lblk_start + num_blks - 1);
3751 /* max possible clusters for this allocation */
3752 allocated_clusters = alloc_cluster_end - alloc_cluster_start + 1;
3754 trace_ext4_get_reserved_cluster_alloc(inode, lblk_start, num_blks);
3756 /* Check towards left side */
3757 c_offset = EXT4_LBLK_COFF(sbi, lblk_start);
3759 lblk_from = EXT4_LBLK_CMASK(sbi, lblk_start);
3760 lblk_to = lblk_from + c_offset - 1;
3762 if (ext4_find_delalloc_range(inode, lblk_from, lblk_to))
3763 allocated_clusters--;
3766 /* Now check towards right. */
3767 c_offset = EXT4_LBLK_COFF(sbi, lblk_start + num_blks);
3768 if (allocated_clusters && c_offset) {
3769 lblk_from = lblk_start + num_blks;
3770 lblk_to = lblk_from + (sbi->s_cluster_ratio - c_offset) - 1;
3772 if (ext4_find_delalloc_range(inode, lblk_from, lblk_to))
3773 allocated_clusters--;
3776 return allocated_clusters;
3780 ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
3781 struct ext4_map_blocks *map,
3782 struct ext4_ext_path *path, int flags,
3783 unsigned int allocated, ext4_fsblk_t newblock)
3787 ext4_io_end_t *io = ext4_inode_aio(inode);
3789 ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical "
3790 "block %llu, max_blocks %u, flags %x, allocated %u\n",
3791 inode->i_ino, (unsigned long long)map->m_lblk, map->m_len,
3793 ext4_ext_show_leaf(inode, path);
3796 * When writing into uninitialized space, we should not fail to
3797 * allocate metadata blocks for the new extent block if needed.
3799 flags |= EXT4_GET_BLOCKS_METADATA_NOFAIL;
3801 trace_ext4_ext_handle_uninitialized_extents(inode, map, flags,
3802 allocated, newblock);
3804 /* get_block() before submit the IO, split the extent */
3805 if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
3806 ret = ext4_split_unwritten_extents(handle, inode, map,
3811 * Flag the inode(non aio case) or end_io struct (aio case)
3812 * that this IO needs to conversion to written when IO is
3816 ext4_set_io_unwritten_flag(inode, io);
3818 ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
3819 map->m_flags |= EXT4_MAP_UNWRITTEN;
3820 if (ext4_should_dioread_nolock(inode))
3821 map->m_flags |= EXT4_MAP_UNINIT;
3824 /* IO end_io complete, convert the filled extent to written */
3825 if ((flags & EXT4_GET_BLOCKS_CONVERT)) {
3826 ret = ext4_convert_unwritten_extents_endio(handle, inode, map,
3829 ext4_update_inode_fsync_trans(handle, inode, 1);
3830 err = check_eofblocks_fl(handle, inode, map->m_lblk,
3834 map->m_flags |= EXT4_MAP_MAPPED;
3835 if (allocated > map->m_len)
3836 allocated = map->m_len;
3837 map->m_len = allocated;
3840 /* buffered IO case */
3842 * repeat fallocate creation request
3843 * we already have an unwritten extent
3845 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT) {
3846 map->m_flags |= EXT4_MAP_UNWRITTEN;
3850 /* buffered READ or buffered write_begin() lookup */
3851 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
3853 * We have blocks reserved already. We
3854 * return allocated blocks so that delalloc
3855 * won't do block reservation for us. But
3856 * the buffer head will be unmapped so that
3857 * a read from the block returns 0s.
3859 map->m_flags |= EXT4_MAP_UNWRITTEN;
3863 /* buffered write, writepage time, convert*/
3864 ret = ext4_ext_convert_to_initialized(handle, inode, map, path, flags);
3866 ext4_update_inode_fsync_trans(handle, inode, 1);
3873 map->m_flags |= EXT4_MAP_NEW;
3875 * if we allocated more blocks than requested
3876 * we need to make sure we unmap the extra block
3877 * allocated. The actual needed block will get
3878 * unmapped later when we find the buffer_head marked
3881 if (allocated > map->m_len) {
3882 unmap_underlying_metadata_blocks(inode->i_sb->s_bdev,
3883 newblock + map->m_len,
3884 allocated - map->m_len);
3885 allocated = map->m_len;
3887 map->m_len = allocated;
3890 * If we have done fallocate with the offset that is already
3891 * delayed allocated, we would have block reservation
3892 * and quota reservation done in the delayed write path.
3893 * But fallocate would have already updated quota and block
3894 * count for this offset. So cancel these reservation
3896 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
3897 unsigned int reserved_clusters;
3898 reserved_clusters = get_reserved_cluster_alloc(inode,
3899 map->m_lblk, map->m_len);
3900 if (reserved_clusters)
3901 ext4_da_update_reserve_space(inode,
3907 map->m_flags |= EXT4_MAP_MAPPED;
3908 if ((flags & EXT4_GET_BLOCKS_KEEP_SIZE) == 0) {
3909 err = check_eofblocks_fl(handle, inode, map->m_lblk, path,
3915 if (allocated > map->m_len)
3916 allocated = map->m_len;
3917 ext4_ext_show_leaf(inode, path);
3918 map->m_pblk = newblock;
3919 map->m_len = allocated;
3922 ext4_ext_drop_refs(path);
3925 return err ? err : allocated;
3929 * get_implied_cluster_alloc - check to see if the requested
3930 * allocation (in the map structure) overlaps with a cluster already
3931 * allocated in an extent.
3932 * @sb The filesystem superblock structure
3933 * @map The requested lblk->pblk mapping
3934 * @ex The extent structure which might contain an implied
3935 * cluster allocation
3937 * This function is called by ext4_ext_map_blocks() after we failed to
3938 * find blocks that were already in the inode's extent tree. Hence,
3939 * we know that the beginning of the requested region cannot overlap
3940 * the extent from the inode's extent tree. There are three cases we
3941 * want to catch. The first is this case:
3943 * |--- cluster # N--|
3944 * |--- extent ---| |---- requested region ---|
3947 * The second case that we need to test for is this one:
3949 * |--------- cluster # N ----------------|
3950 * |--- requested region --| |------- extent ----|
3951 * |=======================|
3953 * The third case is when the requested region lies between two extents
3954 * within the same cluster:
3955 * |------------- cluster # N-------------|
3956 * |----- ex -----| |---- ex_right ----|
3957 * |------ requested region ------|
3958 * |================|
3960 * In each of the above cases, we need to set the map->m_pblk and
3961 * map->m_len so it corresponds to the return the extent labelled as
3962 * "|====|" from cluster #N, since it is already in use for data in
3963 * cluster EXT4_B2C(sbi, map->m_lblk). We will then return 1 to
3964 * signal to ext4_ext_map_blocks() that map->m_pblk should be treated
3965 * as a new "allocated" block region. Otherwise, we will return 0 and
3966 * ext4_ext_map_blocks() will then allocate one or more new clusters
3967 * by calling ext4_mb_new_blocks().
3969 static int get_implied_cluster_alloc(struct super_block *sb,
3970 struct ext4_map_blocks *map,
3971 struct ext4_extent *ex,
3972 struct ext4_ext_path *path)
3974 struct ext4_sb_info *sbi = EXT4_SB(sb);
3975 ext4_lblk_t c_offset = EXT4_LBLK_COFF(sbi, map->m_lblk);
3976 ext4_lblk_t ex_cluster_start, ex_cluster_end;
3977 ext4_lblk_t rr_cluster_start;
3978 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
3979 ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
3980 unsigned short ee_len = ext4_ext_get_actual_len(ex);
3982 /* The extent passed in that we are trying to match */
3983 ex_cluster_start = EXT4_B2C(sbi, ee_block);
3984 ex_cluster_end = EXT4_B2C(sbi, ee_block + ee_len - 1);
3986 /* The requested region passed into ext4_map_blocks() */
3987 rr_cluster_start = EXT4_B2C(sbi, map->m_lblk);
3989 if ((rr_cluster_start == ex_cluster_end) ||
3990 (rr_cluster_start == ex_cluster_start)) {
3991 if (rr_cluster_start == ex_cluster_end)
3992 ee_start += ee_len - 1;
3993 map->m_pblk = EXT4_PBLK_CMASK(sbi, ee_start) + c_offset;
3994 map->m_len = min(map->m_len,
3995 (unsigned) sbi->s_cluster_ratio - c_offset);
3997 * Check for and handle this case:
3999 * |--------- cluster # N-------------|
4000 * |------- extent ----|
4001 * |--- requested region ---|
4005 if (map->m_lblk < ee_block)
4006 map->m_len = min(map->m_len, ee_block - map->m_lblk);
4009 * Check for the case where there is already another allocated
4010 * block to the right of 'ex' but before the end of the cluster.
4012 * |------------- cluster # N-------------|
4013 * |----- ex -----| |---- ex_right ----|
4014 * |------ requested region ------|
4015 * |================|
4017 if (map->m_lblk > ee_block) {
4018 ext4_lblk_t next = ext4_ext_next_allocated_block(path);
4019 map->m_len = min(map->m_len, next - map->m_lblk);
4022 trace_ext4_get_implied_cluster_alloc_exit(sb, map, 1);
4026 trace_ext4_get_implied_cluster_alloc_exit(sb, map, 0);
4032 * Block allocation/map/preallocation routine for extents based files
4035 * Need to be called with
4036 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
4037 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
4039 * return > 0, number of of blocks already mapped/allocated
4040 * if create == 0 and these are pre-allocated blocks
4041 * buffer head is unmapped
4042 * otherwise blocks are mapped
4044 * return = 0, if plain look up failed (blocks have not been allocated)
4045 * buffer head is unmapped
4047 * return < 0, error case.
4049 int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
4050 struct ext4_map_blocks *map, int flags)
4052 struct ext4_ext_path *path = NULL;
4053 struct ext4_extent newex, *ex, *ex2;
4054 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
4055 ext4_fsblk_t newblock = 0;
4056 int free_on_err = 0, err = 0, depth, ret;
4057 unsigned int allocated = 0, offset = 0;
4058 unsigned int allocated_clusters = 0;
4059 struct ext4_allocation_request ar;
4060 ext4_io_end_t *io = ext4_inode_aio(inode);
4061 ext4_lblk_t cluster_offset;
4062 int set_unwritten = 0;
4064 ext_debug("blocks %u/%u requested for inode %lu\n",
4065 map->m_lblk, map->m_len, inode->i_ino);
4066 trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags);
4068 /* find extent for this block */
4069 path = ext4_ext_find_extent(inode, map->m_lblk, NULL);
4071 err = PTR_ERR(path);
4076 depth = ext_depth(inode);
4079 * consistent leaf must not be empty;
4080 * this situation is possible, though, _during_ tree modification;
4081 * this is why assert can't be put in ext4_ext_find_extent()
4083 if (unlikely(path[depth].p_ext == NULL && depth != 0)) {
4084 EXT4_ERROR_INODE(inode, "bad extent address "
4085 "lblock: %lu, depth: %d pblock %lld",
4086 (unsigned long) map->m_lblk, depth,
4087 path[depth].p_block);
4092 ex = path[depth].p_ext;
4094 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
4095 ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
4096 unsigned short ee_len;
4099 * Uninitialized extents are treated as holes, except that
4100 * we split out initialized portions during a write.
4102 ee_len = ext4_ext_get_actual_len(ex);
4104 trace_ext4_ext_show_extent(inode, ee_block, ee_start, ee_len);
4106 /* if found extent covers block, simply return it */
4107 if (in_range(map->m_lblk, ee_block, ee_len)) {
4108 newblock = map->m_lblk - ee_block + ee_start;
4109 /* number of remaining blocks in the extent */
4110 allocated = ee_len - (map->m_lblk - ee_block);
4111 ext_debug("%u fit into %u:%d -> %llu\n", map->m_lblk,
4112 ee_block, ee_len, newblock);
4114 if (!ext4_ext_is_uninitialized(ex))
4117 ret = ext4_ext_handle_uninitialized_extents(
4118 handle, inode, map, path, flags,
4119 allocated, newblock);
4128 if ((sbi->s_cluster_ratio > 1) &&
4129 ext4_find_delalloc_cluster(inode, map->m_lblk))
4130 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4133 * requested block isn't allocated yet;
4134 * we couldn't try to create block if create flag is zero
4136 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
4138 * put just found gap into cache to speed up
4139 * subsequent requests
4141 if ((flags & EXT4_GET_BLOCKS_NO_PUT_HOLE) == 0)
4142 ext4_ext_put_gap_in_cache(inode, path, map->m_lblk);
4147 * Okay, we need to do block allocation.
4149 map->m_flags &= ~EXT4_MAP_FROM_CLUSTER;
4150 newex.ee_block = cpu_to_le32(map->m_lblk);
4151 cluster_offset = EXT4_LBLK_COFF(sbi, map->m_lblk);
4154 * If we are doing bigalloc, check to see if the extent returned
4155 * by ext4_ext_find_extent() implies a cluster we can use.
4157 if (cluster_offset && ex &&
4158 get_implied_cluster_alloc(inode->i_sb, map, ex, path)) {
4159 ar.len = allocated = map->m_len;
4160 newblock = map->m_pblk;
4161 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4162 goto got_allocated_blocks;
4165 /* find neighbour allocated blocks */
4166 ar.lleft = map->m_lblk;
4167 err = ext4_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
4170 ar.lright = map->m_lblk;
4172 err = ext4_ext_search_right(inode, path, &ar.lright, &ar.pright, &ex2);
4176 /* Check if the extent after searching to the right implies a
4177 * cluster we can use. */
4178 if ((sbi->s_cluster_ratio > 1) && ex2 &&
4179 get_implied_cluster_alloc(inode->i_sb, map, ex2, path)) {
4180 ar.len = allocated = map->m_len;
4181 newblock = map->m_pblk;
4182 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4183 goto got_allocated_blocks;
4187 * See if request is beyond maximum number of blocks we can have in
4188 * a single extent. For an initialized extent this limit is
4189 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
4190 * EXT_UNINIT_MAX_LEN.
4192 if (map->m_len > EXT_INIT_MAX_LEN &&
4193 !(flags & EXT4_GET_BLOCKS_UNINIT_EXT))
4194 map->m_len = EXT_INIT_MAX_LEN;
4195 else if (map->m_len > EXT_UNINIT_MAX_LEN &&
4196 (flags & EXT4_GET_BLOCKS_UNINIT_EXT))
4197 map->m_len = EXT_UNINIT_MAX_LEN;
4199 /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
4200 newex.ee_len = cpu_to_le16(map->m_len);
4201 err = ext4_ext_check_overlap(sbi, inode, &newex, path);
4203 allocated = ext4_ext_get_actual_len(&newex);
4205 allocated = map->m_len;
4207 /* allocate new block */
4209 ar.goal = ext4_ext_find_goal(inode, path, map->m_lblk);
4210 ar.logical = map->m_lblk;
4212 * We calculate the offset from the beginning of the cluster
4213 * for the logical block number, since when we allocate a
4214 * physical cluster, the physical block should start at the
4215 * same offset from the beginning of the cluster. This is
4216 * needed so that future calls to get_implied_cluster_alloc()
4219 offset = EXT4_LBLK_COFF(sbi, map->m_lblk);
4220 ar.len = EXT4_NUM_B2C(sbi, offset+allocated);
4222 ar.logical -= offset;
4223 if (S_ISREG(inode->i_mode))
4224 ar.flags = EXT4_MB_HINT_DATA;
4226 /* disable in-core preallocation for non-regular files */
4228 if (flags & EXT4_GET_BLOCKS_NO_NORMALIZE)
4229 ar.flags |= EXT4_MB_HINT_NOPREALLOC;
4230 newblock = ext4_mb_new_blocks(handle, &ar, &err);
4233 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
4234 ar.goal, newblock, allocated);
4236 allocated_clusters = ar.len;
4237 ar.len = EXT4_C2B(sbi, ar.len) - offset;
4238 if (ar.len > allocated)
4241 got_allocated_blocks:
4242 /* try to insert new extent into found leaf and return */
4243 ext4_ext_store_pblock(&newex, newblock + offset);
4244 newex.ee_len = cpu_to_le16(ar.len);
4245 /* Mark uninitialized */
4246 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){
4247 ext4_ext_mark_uninitialized(&newex);
4248 map->m_flags |= EXT4_MAP_UNWRITTEN;
4250 * io_end structure was created for every IO write to an
4251 * uninitialized extent. To avoid unnecessary conversion,
4252 * here we flag the IO that really needs the conversion.
4253 * For non asycn direct IO case, flag the inode state
4254 * that we need to perform conversion when IO is done.
4256 if ((flags & EXT4_GET_BLOCKS_PRE_IO))
4258 if (ext4_should_dioread_nolock(inode))
4259 map->m_flags |= EXT4_MAP_UNINIT;
4263 if ((flags & EXT4_GET_BLOCKS_KEEP_SIZE) == 0)
4264 err = check_eofblocks_fl(handle, inode, map->m_lblk,
4267 err = ext4_ext_insert_extent(handle, inode, path,
4270 if (!err && set_unwritten) {
4272 ext4_set_io_unwritten_flag(inode, io);
4274 ext4_set_inode_state(inode,
4275 EXT4_STATE_DIO_UNWRITTEN);
4278 if (err && free_on_err) {
4279 int fb_flags = flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE ?
4280 EXT4_FREE_BLOCKS_NO_QUOT_UPDATE : 0;
4281 /* free data blocks we just allocated */
4282 /* not a good idea to call discard here directly,
4283 * but otherwise we'd need to call it every free() */
4284 ext4_discard_preallocations(inode);
4285 ext4_free_blocks(handle, inode, NULL, ext4_ext_pblock(&newex),
4286 ext4_ext_get_actual_len(&newex), fb_flags);
4290 /* previous routine could use block we allocated */
4291 newblock = ext4_ext_pblock(&newex);
4292 allocated = ext4_ext_get_actual_len(&newex);
4293 if (allocated > map->m_len)
4294 allocated = map->m_len;
4295 map->m_flags |= EXT4_MAP_NEW;
4298 * Update reserved blocks/metadata blocks after successful
4299 * block allocation which had been deferred till now.
4301 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
4302 unsigned int reserved_clusters;
4304 * Check how many clusters we had reserved this allocated range
4306 reserved_clusters = get_reserved_cluster_alloc(inode,
4307 map->m_lblk, allocated);
4308 if (map->m_flags & EXT4_MAP_FROM_CLUSTER) {
4309 if (reserved_clusters) {
4311 * We have clusters reserved for this range.
4312 * But since we are not doing actual allocation
4313 * and are simply using blocks from previously
4314 * allocated cluster, we should release the
4315 * reservation and not claim quota.
4317 ext4_da_update_reserve_space(inode,
4318 reserved_clusters, 0);
4321 BUG_ON(allocated_clusters < reserved_clusters);
4322 if (reserved_clusters < allocated_clusters) {
4323 struct ext4_inode_info *ei = EXT4_I(inode);
4324 int reservation = allocated_clusters -
4327 * It seems we claimed few clusters outside of
4328 * the range of this allocation. We should give
4329 * it back to the reservation pool. This can
4330 * happen in the following case:
4332 * * Suppose s_cluster_ratio is 4 (i.e., each
4333 * cluster has 4 blocks. Thus, the clusters
4334 * are [0-3],[4-7],[8-11]...
4335 * * First comes delayed allocation write for
4336 * logical blocks 10 & 11. Since there were no
4337 * previous delayed allocated blocks in the
4338 * range [8-11], we would reserve 1 cluster
4340 * * Next comes write for logical blocks 3 to 8.
4341 * In this case, we will reserve 2 clusters
4342 * (for [0-3] and [4-7]; and not for [8-11] as
4343 * that range has a delayed allocated blocks.
4344 * Thus total reserved clusters now becomes 3.
4345 * * Now, during the delayed allocation writeout
4346 * time, we will first write blocks [3-8] and
4347 * allocate 3 clusters for writing these
4348 * blocks. Also, we would claim all these
4349 * three clusters above.
4350 * * Now when we come here to writeout the
4351 * blocks [10-11], we would expect to claim
4352 * the reservation of 1 cluster we had made
4353 * (and we would claim it since there are no
4354 * more delayed allocated blocks in the range
4355 * [8-11]. But our reserved cluster count had
4356 * already gone to 0.
4358 * Thus, at the step 4 above when we determine
4359 * that there are still some unwritten delayed
4360 * allocated blocks outside of our current
4361 * block range, we should increment the
4362 * reserved clusters count so that when the
4363 * remaining blocks finally gets written, we
4366 dquot_reserve_block(inode,
4367 EXT4_C2B(sbi, reservation));
4368 spin_lock(&ei->i_block_reservation_lock);
4369 ei->i_reserved_data_blocks += reservation;
4370 spin_unlock(&ei->i_block_reservation_lock);
4373 * We will claim quota for all newly allocated blocks.
4374 * We're updating the reserved space *after* the
4375 * correction above so we do not accidentally free
4376 * all the metadata reservation because we might
4377 * actually need it later on.
4379 ext4_da_update_reserve_space(inode, allocated_clusters,
4385 * Cache the extent and update transaction to commit on fdatasync only
4386 * when it is _not_ an uninitialized extent.
4388 if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0)
4389 ext4_update_inode_fsync_trans(handle, inode, 1);
4391 ext4_update_inode_fsync_trans(handle, inode, 0);
4393 if (allocated > map->m_len)
4394 allocated = map->m_len;
4395 ext4_ext_show_leaf(inode, path);
4396 map->m_flags |= EXT4_MAP_MAPPED;
4397 map->m_pblk = newblock;
4398 map->m_len = allocated;
4401 ext4_ext_drop_refs(path);
4406 trace_ext4_ext_map_blocks_exit(inode, map, err ? err : allocated);
4408 return err ? err : allocated;
4411 void ext4_ext_truncate(handle_t *handle, struct inode *inode)
4413 struct super_block *sb = inode->i_sb;
4414 ext4_lblk_t last_block;
4418 * TODO: optimization is possible here.
4419 * Probably we need not scan at all,
4420 * because page truncation is enough.
4423 /* we have to know where to truncate from in crash case */
4424 EXT4_I(inode)->i_disksize = inode->i_size;
4425 ext4_mark_inode_dirty(handle, inode);
4427 last_block = (inode->i_size + sb->s_blocksize - 1)
4428 >> EXT4_BLOCK_SIZE_BITS(sb);
4430 err = ext4_es_remove_extent(inode, last_block,
4431 EXT_MAX_BLOCKS - last_block);
4432 if (err == -ENOMEM) {
4434 congestion_wait(BLK_RW_ASYNC, HZ/50);
4438 ext4_std_error(inode->i_sb, err);
4441 err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
4442 ext4_std_error(inode->i_sb, err);
4445 static void ext4_falloc_update_inode(struct inode *inode,
4446 int mode, loff_t new_size, int update_ctime)
4448 struct timespec now;
4451 now = current_fs_time(inode->i_sb);
4452 if (!timespec_equal(&inode->i_ctime, &now))
4453 inode->i_ctime = now;
4456 * Update only when preallocation was requested beyond
4459 if (!(mode & FALLOC_FL_KEEP_SIZE)) {
4460 if (new_size > i_size_read(inode))
4461 i_size_write(inode, new_size);
4462 if (new_size > EXT4_I(inode)->i_disksize)
4463 ext4_update_i_disksize(inode, new_size);
4466 * Mark that we allocate beyond EOF so the subsequent truncate
4467 * can proceed even if the new size is the same as i_size.
4469 if (new_size > i_size_read(inode))
4470 ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
4476 * preallocate space for a file. This implements ext4's fallocate file
4477 * operation, which gets called from sys_fallocate system call.
4478 * For block-mapped files, posix_fallocate should fall back to the method
4479 * of writing zeroes to the required new blocks (the same behavior which is
4480 * expected for file systems which do not support fallocate() system call).
4482 long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
4484 struct inode *inode = file_inode(file);
4487 unsigned int max_blocks;
4492 struct ext4_map_blocks map;
4493 unsigned int credits, blkbits = inode->i_blkbits;
4495 /* Return error if mode is not supported */
4496 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
4499 if (mode & FALLOC_FL_PUNCH_HOLE)
4500 return ext4_punch_hole(file, offset, len);
4502 ret = ext4_convert_inline_data(inode);
4507 * currently supporting (pre)allocate mode for extent-based
4510 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
4513 trace_ext4_fallocate_enter(inode, offset, len, mode);
4514 map.m_lblk = offset >> blkbits;
4516 * We can't just convert len to max_blocks because
4517 * If blocksize = 4096 offset = 3072 and len = 2048
4519 max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
4522 * credits to insert 1 extent into extent tree
4524 credits = ext4_chunk_trans_blocks(inode, max_blocks);
4525 mutex_lock(&inode->i_mutex);
4526 ret = inode_newsize_ok(inode, (len + offset));
4528 mutex_unlock(&inode->i_mutex);
4529 trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
4532 flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT;
4533 if (mode & FALLOC_FL_KEEP_SIZE)
4534 flags |= EXT4_GET_BLOCKS_KEEP_SIZE;
4536 * Don't normalize the request if it can fit in one extent so
4537 * that it doesn't get unnecessarily split into multiple
4540 if (len <= EXT_UNINIT_MAX_LEN << blkbits)
4541 flags |= EXT4_GET_BLOCKS_NO_NORMALIZE;
4544 while (ret >= 0 && ret < max_blocks) {
4545 map.m_lblk = map.m_lblk + ret;
4546 map.m_len = max_blocks = max_blocks - ret;
4547 handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS,
4549 if (IS_ERR(handle)) {
4550 ret = PTR_ERR(handle);
4553 ret = ext4_map_blocks(handle, inode, &map, flags);
4556 ext4_warning(inode->i_sb,
4557 "inode #%lu: block %u: len %u: "
4558 "ext4_ext_map_blocks returned %d",
4559 inode->i_ino, map.m_lblk,
4562 ext4_mark_inode_dirty(handle, inode);
4563 ret2 = ext4_journal_stop(handle);
4566 if ((map.m_lblk + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
4567 blkbits) >> blkbits))
4568 new_size = offset + len;
4570 new_size = ((loff_t) map.m_lblk + ret) << blkbits;
4572 ext4_falloc_update_inode(inode, mode, new_size,
4573 (map.m_flags & EXT4_MAP_NEW));
4574 ext4_mark_inode_dirty(handle, inode);
4575 if ((file->f_flags & O_SYNC) && ret >= max_blocks)
4576 ext4_handle_sync(handle);
4577 ret2 = ext4_journal_stop(handle);
4581 if (ret == -ENOSPC &&
4582 ext4_should_retry_alloc(inode->i_sb, &retries)) {
4586 mutex_unlock(&inode->i_mutex);
4587 trace_ext4_fallocate_exit(inode, offset, max_blocks,
4588 ret > 0 ? ret2 : ret);
4589 return ret > 0 ? ret2 : ret;
4593 * This function convert a range of blocks to written extents
4594 * The caller of this function will pass the start offset and the size.
4595 * all unwritten extents within this range will be converted to
4598 * This function is called from the direct IO end io call back
4599 * function, to convert the fallocated extents after IO is completed.
4600 * Returns 0 on success.
4602 int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
4606 unsigned int max_blocks;
4609 struct ext4_map_blocks map;
4610 unsigned int credits, blkbits = inode->i_blkbits;
4612 map.m_lblk = offset >> blkbits;
4614 * We can't just convert len to max_blocks because
4615 * If blocksize = 4096 offset = 3072 and len = 2048
4617 max_blocks = ((EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) -
4620 * credits to insert 1 extent into extent tree
4622 credits = ext4_chunk_trans_blocks(inode, max_blocks);
4623 while (ret >= 0 && ret < max_blocks) {
4625 map.m_len = (max_blocks -= ret);
4626 handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, credits);
4627 if (IS_ERR(handle)) {
4628 ret = PTR_ERR(handle);
4631 ret = ext4_map_blocks(handle, inode, &map,
4632 EXT4_GET_BLOCKS_IO_CONVERT_EXT);
4634 ext4_warning(inode->i_sb,
4635 "inode #%lu: block %u: len %u: "
4636 "ext4_ext_map_blocks returned %d",
4637 inode->i_ino, map.m_lblk,
4639 ext4_mark_inode_dirty(handle, inode);
4640 ret2 = ext4_journal_stop(handle);
4641 if (ret <= 0 || ret2 )
4644 return ret > 0 ? ret2 : ret;
4648 * If newes is not existing extent (newes->ec_pblk equals zero) find
4649 * delayed extent at start of newes and update newes accordingly and
4650 * return start of the next delayed extent.
4652 * If newes is existing extent (newes->ec_pblk is not equal zero)
4653 * return start of next delayed extent or EXT_MAX_BLOCKS if no delayed
4654 * extent found. Leave newes unmodified.
4656 static int ext4_find_delayed_extent(struct inode *inode,
4657 struct extent_status *newes)
4659 struct extent_status es;
4660 ext4_lblk_t block, next_del;
4662 if (newes->es_pblk == 0) {
4663 ext4_es_find_delayed_extent_range(inode, newes->es_lblk,
4664 newes->es_lblk + newes->es_len - 1, &es);
4667 * No extent in extent-tree contains block @newes->es_pblk,
4668 * then the block may stay in 1)a hole or 2)delayed-extent.
4674 if (es.es_lblk > newes->es_lblk) {
4676 newes->es_len = min(es.es_lblk - newes->es_lblk,
4681 newes->es_len = es.es_lblk + es.es_len - newes->es_lblk;
4684 block = newes->es_lblk + newes->es_len;
4685 ext4_es_find_delayed_extent_range(inode, block, EXT_MAX_BLOCKS, &es);
4687 next_del = EXT_MAX_BLOCKS;
4689 next_del = es.es_lblk;
4693 /* fiemap flags we can handle specified here */
4694 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
4696 static int ext4_xattr_fiemap(struct inode *inode,
4697 struct fiemap_extent_info *fieinfo)
4701 __u32 flags = FIEMAP_EXTENT_LAST;
4702 int blockbits = inode->i_sb->s_blocksize_bits;
4706 if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
4707 struct ext4_iloc iloc;
4708 int offset; /* offset of xattr in inode */
4710 error = ext4_get_inode_loc(inode, &iloc);
4713 physical = (__u64)iloc.bh->b_blocknr << blockbits;
4714 offset = EXT4_GOOD_OLD_INODE_SIZE +
4715 EXT4_I(inode)->i_extra_isize;
4717 length = EXT4_SB(inode->i_sb)->s_inode_size - offset;
4718 flags |= FIEMAP_EXTENT_DATA_INLINE;
4720 } else { /* external block */
4721 physical = (__u64)EXT4_I(inode)->i_file_acl << blockbits;
4722 length = inode->i_sb->s_blocksize;
4726 error = fiemap_fill_next_extent(fieinfo, 0, physical,
4728 return (error < 0 ? error : 0);
4731 int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
4732 __u64 start, __u64 len)
4734 ext4_lblk_t start_blk;
4737 if (ext4_has_inline_data(inode)) {
4740 error = ext4_inline_data_fiemap(inode, fieinfo, &has_inline);
4746 /* fallback to generic here if not in extents fmt */
4747 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
4748 return generic_block_fiemap(inode, fieinfo, start, len,
4751 if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
4754 if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
4755 error = ext4_xattr_fiemap(inode, fieinfo);
4757 ext4_lblk_t len_blks;
4760 start_blk = start >> inode->i_sb->s_blocksize_bits;
4761 last_blk = (start + len - 1) >> inode->i_sb->s_blocksize_bits;
4762 if (last_blk >= EXT_MAX_BLOCKS)
4763 last_blk = EXT_MAX_BLOCKS-1;
4764 len_blks = ((ext4_lblk_t) last_blk) - start_blk + 1;
4767 * Walk the extent tree gathering extent information
4768 * and pushing extents back to the user.
4770 error = ext4_fill_fiemap_extents(inode, start_blk,