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);
366 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
369 static int ext4_valid_extent_idx(struct inode *inode,
370 struct ext4_extent_idx *ext_idx)
372 ext4_fsblk_t block = ext4_idx_pblock(ext_idx);
374 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, 1);
377 static int ext4_valid_extent_entries(struct inode *inode,
378 struct ext4_extent_header *eh,
381 unsigned short entries;
382 if (eh->eh_entries == 0)
385 entries = le16_to_cpu(eh->eh_entries);
389 struct ext4_extent *ext = EXT_FIRST_EXTENT(eh);
391 if (!ext4_valid_extent(inode, ext))
397 struct ext4_extent_idx *ext_idx = EXT_FIRST_INDEX(eh);
399 if (!ext4_valid_extent_idx(inode, ext_idx))
408 static int __ext4_ext_check(const char *function, unsigned int line,
409 struct inode *inode, struct ext4_extent_header *eh,
412 const char *error_msg;
415 if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
416 error_msg = "invalid magic";
419 if (unlikely(le16_to_cpu(eh->eh_depth) != depth)) {
420 error_msg = "unexpected eh_depth";
423 if (unlikely(eh->eh_max == 0)) {
424 error_msg = "invalid eh_max";
427 max = ext4_ext_max_entries(inode, depth);
428 if (unlikely(le16_to_cpu(eh->eh_max) > max)) {
429 error_msg = "too large eh_max";
432 if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
433 error_msg = "invalid eh_entries";
436 if (!ext4_valid_extent_entries(inode, eh, depth)) {
437 error_msg = "invalid extent entries";
440 /* Verify checksum on non-root extent tree nodes */
441 if (ext_depth(inode) != depth &&
442 !ext4_extent_block_csum_verify(inode, eh)) {
443 error_msg = "extent tree corrupted";
449 ext4_error_inode(inode, function, line, 0,
450 "bad header/extent: %s - magic %x, "
451 "entries %u, max %u(%u), depth %u(%u)",
452 error_msg, le16_to_cpu(eh->eh_magic),
453 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
454 max, le16_to_cpu(eh->eh_depth), depth);
459 #define ext4_ext_check(inode, eh, depth) \
460 __ext4_ext_check(__func__, __LINE__, inode, eh, depth)
462 int ext4_ext_check_inode(struct inode *inode)
464 return ext4_ext_check(inode, ext_inode_hdr(inode), ext_depth(inode));
467 static int __ext4_ext_check_block(const char *function, unsigned int line,
469 struct ext4_extent_header *eh,
471 struct buffer_head *bh)
475 if (buffer_verified(bh))
477 ret = ext4_ext_check(inode, eh, depth);
480 set_buffer_verified(bh);
484 #define ext4_ext_check_block(inode, eh, depth, bh) \
485 __ext4_ext_check_block(__func__, __LINE__, inode, eh, depth, bh)
488 static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
490 int k, l = path->p_depth;
493 for (k = 0; k <= l; k++, path++) {
495 ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
496 ext4_idx_pblock(path->p_idx));
497 } else if (path->p_ext) {
498 ext_debug(" %d:[%d]%d:%llu ",
499 le32_to_cpu(path->p_ext->ee_block),
500 ext4_ext_is_uninitialized(path->p_ext),
501 ext4_ext_get_actual_len(path->p_ext),
502 ext4_ext_pblock(path->p_ext));
509 static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
511 int depth = ext_depth(inode);
512 struct ext4_extent_header *eh;
513 struct ext4_extent *ex;
519 eh = path[depth].p_hdr;
520 ex = EXT_FIRST_EXTENT(eh);
522 ext_debug("Displaying leaf extents for inode %lu\n", inode->i_ino);
524 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
525 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block),
526 ext4_ext_is_uninitialized(ex),
527 ext4_ext_get_actual_len(ex), ext4_ext_pblock(ex));
532 static void ext4_ext_show_move(struct inode *inode, struct ext4_ext_path *path,
533 ext4_fsblk_t newblock, int level)
535 int depth = ext_depth(inode);
536 struct ext4_extent *ex;
538 if (depth != level) {
539 struct ext4_extent_idx *idx;
540 idx = path[level].p_idx;
541 while (idx <= EXT_MAX_INDEX(path[level].p_hdr)) {
542 ext_debug("%d: move %d:%llu in new index %llu\n", level,
543 le32_to_cpu(idx->ei_block),
544 ext4_idx_pblock(idx),
552 ex = path[depth].p_ext;
553 while (ex <= EXT_MAX_EXTENT(path[depth].p_hdr)) {
554 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
555 le32_to_cpu(ex->ee_block),
557 ext4_ext_is_uninitialized(ex),
558 ext4_ext_get_actual_len(ex),
565 #define ext4_ext_show_path(inode, path)
566 #define ext4_ext_show_leaf(inode, path)
567 #define ext4_ext_show_move(inode, path, newblock, level)
570 void ext4_ext_drop_refs(struct ext4_ext_path *path)
572 int depth = path->p_depth;
575 for (i = 0; i <= depth; i++, path++)
583 * ext4_ext_binsearch_idx:
584 * binary search for the closest index of the given block
585 * the header must be checked before calling this
588 ext4_ext_binsearch_idx(struct inode *inode,
589 struct ext4_ext_path *path, ext4_lblk_t block)
591 struct ext4_extent_header *eh = path->p_hdr;
592 struct ext4_extent_idx *r, *l, *m;
595 ext_debug("binsearch for %u(idx): ", block);
597 l = EXT_FIRST_INDEX(eh) + 1;
598 r = EXT_LAST_INDEX(eh);
601 if (block < le32_to_cpu(m->ei_block))
605 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block),
606 m, le32_to_cpu(m->ei_block),
607 r, le32_to_cpu(r->ei_block));
611 ext_debug(" -> %u->%lld ", le32_to_cpu(path->p_idx->ei_block),
612 ext4_idx_pblock(path->p_idx));
614 #ifdef CHECK_BINSEARCH
616 struct ext4_extent_idx *chix, *ix;
619 chix = ix = EXT_FIRST_INDEX(eh);
620 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
622 le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
623 printk(KERN_DEBUG "k=%d, ix=0x%p, "
625 ix, EXT_FIRST_INDEX(eh));
626 printk(KERN_DEBUG "%u <= %u\n",
627 le32_to_cpu(ix->ei_block),
628 le32_to_cpu(ix[-1].ei_block));
630 BUG_ON(k && le32_to_cpu(ix->ei_block)
631 <= le32_to_cpu(ix[-1].ei_block));
632 if (block < le32_to_cpu(ix->ei_block))
636 BUG_ON(chix != path->p_idx);
643 * ext4_ext_binsearch:
644 * binary search for closest extent of the given block
645 * the header must be checked before calling this
648 ext4_ext_binsearch(struct inode *inode,
649 struct ext4_ext_path *path, ext4_lblk_t block)
651 struct ext4_extent_header *eh = path->p_hdr;
652 struct ext4_extent *r, *l, *m;
654 if (eh->eh_entries == 0) {
656 * this leaf is empty:
657 * we get such a leaf in split/add case
662 ext_debug("binsearch for %u: ", block);
664 l = EXT_FIRST_EXTENT(eh) + 1;
665 r = EXT_LAST_EXTENT(eh);
669 if (block < le32_to_cpu(m->ee_block))
673 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block),
674 m, le32_to_cpu(m->ee_block),
675 r, le32_to_cpu(r->ee_block));
679 ext_debug(" -> %d:%llu:[%d]%d ",
680 le32_to_cpu(path->p_ext->ee_block),
681 ext4_ext_pblock(path->p_ext),
682 ext4_ext_is_uninitialized(path->p_ext),
683 ext4_ext_get_actual_len(path->p_ext));
685 #ifdef CHECK_BINSEARCH
687 struct ext4_extent *chex, *ex;
690 chex = ex = EXT_FIRST_EXTENT(eh);
691 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
692 BUG_ON(k && le32_to_cpu(ex->ee_block)
693 <= le32_to_cpu(ex[-1].ee_block));
694 if (block < le32_to_cpu(ex->ee_block))
698 BUG_ON(chex != path->p_ext);
704 int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
706 struct ext4_extent_header *eh;
708 eh = ext_inode_hdr(inode);
711 eh->eh_magic = EXT4_EXT_MAGIC;
712 eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode, 0));
713 ext4_mark_inode_dirty(handle, inode);
717 struct ext4_ext_path *
718 ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
719 struct ext4_ext_path *path)
721 struct ext4_extent_header *eh;
722 struct buffer_head *bh;
723 short int depth, i, ppos = 0, alloc = 0;
726 eh = ext_inode_hdr(inode);
727 depth = ext_depth(inode);
729 /* account possible depth increase */
731 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 2),
734 return ERR_PTR(-ENOMEM);
741 /* walk through the tree */
743 ext_debug("depth %d: num %d, max %d\n",
744 ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
746 ext4_ext_binsearch_idx(inode, path + ppos, block);
747 path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx);
748 path[ppos].p_depth = i;
749 path[ppos].p_ext = NULL;
751 bh = sb_getblk(inode->i_sb, path[ppos].p_block);
756 if (!bh_uptodate_or_lock(bh)) {
757 trace_ext4_ext_load_extent(inode, block,
759 ret = bh_submit_read(bh);
765 eh = ext_block_hdr(bh);
767 if (unlikely(ppos > depth)) {
769 EXT4_ERROR_INODE(inode,
770 "ppos %d > depth %d", ppos, depth);
774 path[ppos].p_bh = bh;
775 path[ppos].p_hdr = eh;
778 ret = ext4_ext_check_block(inode, eh, i, bh);
783 path[ppos].p_depth = i;
784 path[ppos].p_ext = NULL;
785 path[ppos].p_idx = NULL;
788 ext4_ext_binsearch(inode, path + ppos, block);
789 /* if not an empty leaf */
790 if (path[ppos].p_ext)
791 path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext);
793 ext4_ext_show_path(inode, path);
798 ext4_ext_drop_refs(path);
805 * ext4_ext_insert_index:
806 * insert new index [@logical;@ptr] into the block at @curp;
807 * check where to insert: before @curp or after @curp
809 static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
810 struct ext4_ext_path *curp,
811 int logical, ext4_fsblk_t ptr)
813 struct ext4_extent_idx *ix;
816 err = ext4_ext_get_access(handle, inode, curp);
820 if (unlikely(logical == le32_to_cpu(curp->p_idx->ei_block))) {
821 EXT4_ERROR_INODE(inode,
822 "logical %d == ei_block %d!",
823 logical, le32_to_cpu(curp->p_idx->ei_block));
827 if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries)
828 >= le16_to_cpu(curp->p_hdr->eh_max))) {
829 EXT4_ERROR_INODE(inode,
830 "eh_entries %d >= eh_max %d!",
831 le16_to_cpu(curp->p_hdr->eh_entries),
832 le16_to_cpu(curp->p_hdr->eh_max));
836 if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
838 ext_debug("insert new index %d after: %llu\n", logical, ptr);
839 ix = curp->p_idx + 1;
842 ext_debug("insert new index %d before: %llu\n", logical, ptr);
846 len = EXT_LAST_INDEX(curp->p_hdr) - ix + 1;
849 ext_debug("insert new index %d: "
850 "move %d indices from 0x%p to 0x%p\n",
851 logical, len, ix, ix + 1);
852 memmove(ix + 1, ix, len * sizeof(struct ext4_extent_idx));
855 if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) {
856 EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!");
860 ix->ei_block = cpu_to_le32(logical);
861 ext4_idx_store_pblock(ix, ptr);
862 le16_add_cpu(&curp->p_hdr->eh_entries, 1);
864 if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) {
865 EXT4_ERROR_INODE(inode, "ix > EXT_LAST_INDEX!");
869 err = ext4_ext_dirty(handle, inode, curp);
870 ext4_std_error(inode->i_sb, err);
877 * inserts new subtree into the path, using free index entry
879 * - allocates all needed blocks (new leaf and all intermediate index blocks)
880 * - makes decision where to split
881 * - moves remaining extents and index entries (right to the split point)
882 * into the newly allocated blocks
883 * - initializes subtree
885 static int ext4_ext_split(handle_t *handle, struct inode *inode,
887 struct ext4_ext_path *path,
888 struct ext4_extent *newext, int at)
890 struct buffer_head *bh = NULL;
891 int depth = ext_depth(inode);
892 struct ext4_extent_header *neh;
893 struct ext4_extent_idx *fidx;
895 ext4_fsblk_t newblock, oldblock;
897 ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */
900 /* make decision: where to split? */
901 /* FIXME: now decision is simplest: at current extent */
903 /* if current leaf will be split, then we should use
904 * border from split point */
905 if (unlikely(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr))) {
906 EXT4_ERROR_INODE(inode, "p_ext > EXT_MAX_EXTENT!");
909 if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
910 border = path[depth].p_ext[1].ee_block;
911 ext_debug("leaf will be split."
912 " next leaf starts at %d\n",
913 le32_to_cpu(border));
915 border = newext->ee_block;
916 ext_debug("leaf will be added."
917 " next leaf starts at %d\n",
918 le32_to_cpu(border));
922 * If error occurs, then we break processing
923 * and mark filesystem read-only. index won't
924 * be inserted and tree will be in consistent
925 * state. Next mount will repair buffers too.
929 * Get array to track all allocated blocks.
930 * We need this to handle errors and free blocks
933 ablocks = kzalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS);
937 /* allocate all needed blocks */
938 ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
939 for (a = 0; a < depth - at; a++) {
940 newblock = ext4_ext_new_meta_block(handle, inode, path,
941 newext, &err, flags);
944 ablocks[a] = newblock;
947 /* initialize new leaf */
948 newblock = ablocks[--a];
949 if (unlikely(newblock == 0)) {
950 EXT4_ERROR_INODE(inode, "newblock == 0!");
954 bh = sb_getblk(inode->i_sb, newblock);
961 err = ext4_journal_get_create_access(handle, bh);
965 neh = ext_block_hdr(bh);
967 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
968 neh->eh_magic = EXT4_EXT_MAGIC;
971 /* move remainder of path[depth] to the new leaf */
972 if (unlikely(path[depth].p_hdr->eh_entries !=
973 path[depth].p_hdr->eh_max)) {
974 EXT4_ERROR_INODE(inode, "eh_entries %d != eh_max %d!",
975 path[depth].p_hdr->eh_entries,
976 path[depth].p_hdr->eh_max);
980 /* start copy from next extent */
981 m = EXT_MAX_EXTENT(path[depth].p_hdr) - path[depth].p_ext++;
982 ext4_ext_show_move(inode, path, newblock, depth);
984 struct ext4_extent *ex;
985 ex = EXT_FIRST_EXTENT(neh);
986 memmove(ex, path[depth].p_ext, sizeof(struct ext4_extent) * m);
987 le16_add_cpu(&neh->eh_entries, m);
990 ext4_extent_block_csum_set(inode, neh);
991 set_buffer_uptodate(bh);
994 err = ext4_handle_dirty_metadata(handle, inode, bh);
1000 /* correct old leaf */
1002 err = ext4_ext_get_access(handle, inode, path + depth);
1005 le16_add_cpu(&path[depth].p_hdr->eh_entries, -m);
1006 err = ext4_ext_dirty(handle, inode, path + depth);
1012 /* create intermediate indexes */
1014 if (unlikely(k < 0)) {
1015 EXT4_ERROR_INODE(inode, "k %d < 0!", k);
1020 ext_debug("create %d intermediate indices\n", k);
1021 /* insert new index into current index block */
1022 /* current depth stored in i var */
1025 oldblock = newblock;
1026 newblock = ablocks[--a];
1027 bh = sb_getblk(inode->i_sb, newblock);
1028 if (unlikely(!bh)) {
1034 err = ext4_journal_get_create_access(handle, bh);
1038 neh = ext_block_hdr(bh);
1039 neh->eh_entries = cpu_to_le16(1);
1040 neh->eh_magic = EXT4_EXT_MAGIC;
1041 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
1042 neh->eh_depth = cpu_to_le16(depth - i);
1043 fidx = EXT_FIRST_INDEX(neh);
1044 fidx->ei_block = border;
1045 ext4_idx_store_pblock(fidx, oldblock);
1047 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
1048 i, newblock, le32_to_cpu(border), oldblock);
1050 /* move remainder of path[i] to the new index block */
1051 if (unlikely(EXT_MAX_INDEX(path[i].p_hdr) !=
1052 EXT_LAST_INDEX(path[i].p_hdr))) {
1053 EXT4_ERROR_INODE(inode,
1054 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
1055 le32_to_cpu(path[i].p_ext->ee_block));
1059 /* start copy indexes */
1060 m = EXT_MAX_INDEX(path[i].p_hdr) - path[i].p_idx++;
1061 ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
1062 EXT_MAX_INDEX(path[i].p_hdr));
1063 ext4_ext_show_move(inode, path, newblock, i);
1065 memmove(++fidx, path[i].p_idx,
1066 sizeof(struct ext4_extent_idx) * m);
1067 le16_add_cpu(&neh->eh_entries, m);
1069 ext4_extent_block_csum_set(inode, neh);
1070 set_buffer_uptodate(bh);
1073 err = ext4_handle_dirty_metadata(handle, inode, bh);
1079 /* correct old index */
1081 err = ext4_ext_get_access(handle, inode, path + i);
1084 le16_add_cpu(&path[i].p_hdr->eh_entries, -m);
1085 err = ext4_ext_dirty(handle, inode, path + i);
1093 /* insert new index */
1094 err = ext4_ext_insert_index(handle, inode, path + at,
1095 le32_to_cpu(border), newblock);
1099 if (buffer_locked(bh))
1105 /* free all allocated blocks in error case */
1106 for (i = 0; i < depth; i++) {
1109 ext4_free_blocks(handle, inode, NULL, ablocks[i], 1,
1110 EXT4_FREE_BLOCKS_METADATA);
1119 * ext4_ext_grow_indepth:
1120 * implements tree growing procedure:
1121 * - allocates new block
1122 * - moves top-level data (index block or leaf) into the new block
1123 * - initializes new top-level, creating index that points to the
1124 * just created block
1126 static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
1128 struct ext4_extent *newext)
1130 struct ext4_extent_header *neh;
1131 struct buffer_head *bh;
1132 ext4_fsblk_t newblock;
1135 newblock = ext4_ext_new_meta_block(handle, inode, NULL,
1136 newext, &err, flags);
1140 bh = sb_getblk(inode->i_sb, newblock);
1145 err = ext4_journal_get_create_access(handle, bh);
1151 /* move top-level index/leaf into new block */
1152 memmove(bh->b_data, EXT4_I(inode)->i_data,
1153 sizeof(EXT4_I(inode)->i_data));
1155 /* set size of new block */
1156 neh = ext_block_hdr(bh);
1157 /* old root could have indexes or leaves
1158 * so calculate e_max right way */
1159 if (ext_depth(inode))
1160 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
1162 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
1163 neh->eh_magic = EXT4_EXT_MAGIC;
1164 ext4_extent_block_csum_set(inode, neh);
1165 set_buffer_uptodate(bh);
1168 err = ext4_handle_dirty_metadata(handle, inode, bh);
1172 /* Update top-level index: num,max,pointer */
1173 neh = ext_inode_hdr(inode);
1174 neh->eh_entries = cpu_to_le16(1);
1175 ext4_idx_store_pblock(EXT_FIRST_INDEX(neh), newblock);
1176 if (neh->eh_depth == 0) {
1177 /* Root extent block becomes index block */
1178 neh->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode, 0));
1179 EXT_FIRST_INDEX(neh)->ei_block =
1180 EXT_FIRST_EXTENT(neh)->ee_block;
1182 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1183 le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
1184 le32_to_cpu(EXT_FIRST_INDEX(neh)->ei_block),
1185 ext4_idx_pblock(EXT_FIRST_INDEX(neh)));
1187 le16_add_cpu(&neh->eh_depth, 1);
1188 ext4_mark_inode_dirty(handle, inode);
1196 * ext4_ext_create_new_leaf:
1197 * finds empty index and adds new leaf.
1198 * if no free index is found, then it requests in-depth growing.
1200 static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
1202 struct ext4_ext_path *path,
1203 struct ext4_extent *newext)
1205 struct ext4_ext_path *curp;
1206 int depth, i, err = 0;
1209 i = depth = ext_depth(inode);
1211 /* walk up to the tree and look for free index entry */
1212 curp = path + depth;
1213 while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
1218 /* we use already allocated block for index block,
1219 * so subsequent data blocks should be contiguous */
1220 if (EXT_HAS_FREE_INDEX(curp)) {
1221 /* if we found index with free entry, then use that
1222 * entry: create all needed subtree and add new leaf */
1223 err = ext4_ext_split(handle, inode, flags, path, newext, i);
1228 ext4_ext_drop_refs(path);
1229 path = ext4_ext_find_extent(inode,
1230 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1233 err = PTR_ERR(path);
1235 /* tree is full, time to grow in depth */
1236 err = ext4_ext_grow_indepth(handle, inode, flags, newext);
1241 ext4_ext_drop_refs(path);
1242 path = ext4_ext_find_extent(inode,
1243 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1246 err = PTR_ERR(path);
1251 * only first (depth 0 -> 1) produces free space;
1252 * in all other cases we have to split the grown tree
1254 depth = ext_depth(inode);
1255 if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
1256 /* now we need to split */
1266 * search the closest allocated block to the left for *logical
1267 * and returns it at @logical + it's physical address at @phys
1268 * if *logical is the smallest allocated block, the function
1269 * returns 0 at @phys
1270 * return value contains 0 (success) or error code
1272 static int ext4_ext_search_left(struct inode *inode,
1273 struct ext4_ext_path *path,
1274 ext4_lblk_t *logical, ext4_fsblk_t *phys)
1276 struct ext4_extent_idx *ix;
1277 struct ext4_extent *ex;
1280 if (unlikely(path == NULL)) {
1281 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1284 depth = path->p_depth;
1287 if (depth == 0 && path->p_ext == NULL)
1290 /* usually extent in the path covers blocks smaller
1291 * then *logical, but it can be that extent is the
1292 * first one in the file */
1294 ex = path[depth].p_ext;
1295 ee_len = ext4_ext_get_actual_len(ex);
1296 if (*logical < le32_to_cpu(ex->ee_block)) {
1297 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1298 EXT4_ERROR_INODE(inode,
1299 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
1300 *logical, le32_to_cpu(ex->ee_block));
1303 while (--depth >= 0) {
1304 ix = path[depth].p_idx;
1305 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1306 EXT4_ERROR_INODE(inode,
1307 "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
1308 ix != NULL ? le32_to_cpu(ix->ei_block) : 0,
1309 EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ?
1310 le32_to_cpu(EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block) : 0,
1318 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1319 EXT4_ERROR_INODE(inode,
1320 "logical %d < ee_block %d + ee_len %d!",
1321 *logical, le32_to_cpu(ex->ee_block), ee_len);
1325 *logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
1326 *phys = ext4_ext_pblock(ex) + ee_len - 1;
1331 * search the closest allocated block to the right for *logical
1332 * and returns it at @logical + it's physical address at @phys
1333 * if *logical is the largest allocated block, the function
1334 * returns 0 at @phys
1335 * return value contains 0 (success) or error code
1337 static int ext4_ext_search_right(struct inode *inode,
1338 struct ext4_ext_path *path,
1339 ext4_lblk_t *logical, ext4_fsblk_t *phys,
1340 struct ext4_extent **ret_ex)
1342 struct buffer_head *bh = NULL;
1343 struct ext4_extent_header *eh;
1344 struct ext4_extent_idx *ix;
1345 struct ext4_extent *ex;
1347 int depth; /* Note, NOT eh_depth; depth from top of tree */
1350 if (unlikely(path == NULL)) {
1351 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1354 depth = path->p_depth;
1357 if (depth == 0 && path->p_ext == NULL)
1360 /* usually extent in the path covers blocks smaller
1361 * then *logical, but it can be that extent is the
1362 * first one in the file */
1364 ex = path[depth].p_ext;
1365 ee_len = ext4_ext_get_actual_len(ex);
1366 if (*logical < le32_to_cpu(ex->ee_block)) {
1367 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1368 EXT4_ERROR_INODE(inode,
1369 "first_extent(path[%d].p_hdr) != ex",
1373 while (--depth >= 0) {
1374 ix = path[depth].p_idx;
1375 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1376 EXT4_ERROR_INODE(inode,
1377 "ix != EXT_FIRST_INDEX *logical %d!",
1385 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1386 EXT4_ERROR_INODE(inode,
1387 "logical %d < ee_block %d + ee_len %d!",
1388 *logical, le32_to_cpu(ex->ee_block), ee_len);
1392 if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
1393 /* next allocated block in this leaf */
1398 /* go up and search for index to the right */
1399 while (--depth >= 0) {
1400 ix = path[depth].p_idx;
1401 if (ix != EXT_LAST_INDEX(path[depth].p_hdr))
1405 /* we've gone up to the root and found no index to the right */
1409 /* we've found index to the right, let's
1410 * follow it and find the closest allocated
1411 * block to the right */
1413 block = ext4_idx_pblock(ix);
1414 while (++depth < path->p_depth) {
1415 bh = sb_bread(inode->i_sb, block);
1418 eh = ext_block_hdr(bh);
1419 /* subtract from p_depth to get proper eh_depth */
1420 if (ext4_ext_check_block(inode, eh,
1421 path->p_depth - depth, bh)) {
1425 ix = EXT_FIRST_INDEX(eh);
1426 block = ext4_idx_pblock(ix);
1430 bh = sb_bread(inode->i_sb, block);
1433 eh = ext_block_hdr(bh);
1434 if (ext4_ext_check_block(inode, eh, path->p_depth - depth, bh)) {
1438 ex = EXT_FIRST_EXTENT(eh);
1440 *logical = le32_to_cpu(ex->ee_block);
1441 *phys = ext4_ext_pblock(ex);
1449 * ext4_ext_next_allocated_block:
1450 * returns allocated block in subsequent extent or EXT_MAX_BLOCKS.
1451 * NOTE: it considers block number from index entry as
1452 * allocated block. Thus, index entries have to be consistent
1456 ext4_ext_next_allocated_block(struct ext4_ext_path *path)
1460 BUG_ON(path == NULL);
1461 depth = path->p_depth;
1463 if (depth == 0 && path->p_ext == NULL)
1464 return EXT_MAX_BLOCKS;
1466 while (depth >= 0) {
1467 if (depth == path->p_depth) {
1469 if (path[depth].p_ext &&
1470 path[depth].p_ext !=
1471 EXT_LAST_EXTENT(path[depth].p_hdr))
1472 return le32_to_cpu(path[depth].p_ext[1].ee_block);
1475 if (path[depth].p_idx !=
1476 EXT_LAST_INDEX(path[depth].p_hdr))
1477 return le32_to_cpu(path[depth].p_idx[1].ei_block);
1482 return EXT_MAX_BLOCKS;
1486 * ext4_ext_next_leaf_block:
1487 * returns first allocated block from next leaf or EXT_MAX_BLOCKS
1489 static ext4_lblk_t ext4_ext_next_leaf_block(struct ext4_ext_path *path)
1493 BUG_ON(path == NULL);
1494 depth = path->p_depth;
1496 /* zero-tree has no leaf blocks at all */
1498 return EXT_MAX_BLOCKS;
1500 /* go to index block */
1503 while (depth >= 0) {
1504 if (path[depth].p_idx !=
1505 EXT_LAST_INDEX(path[depth].p_hdr))
1506 return (ext4_lblk_t)
1507 le32_to_cpu(path[depth].p_idx[1].ei_block);
1511 return EXT_MAX_BLOCKS;
1515 * ext4_ext_correct_indexes:
1516 * if leaf gets modified and modified extent is first in the leaf,
1517 * then we have to correct all indexes above.
1518 * TODO: do we need to correct tree in all cases?
1520 static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
1521 struct ext4_ext_path *path)
1523 struct ext4_extent_header *eh;
1524 int depth = ext_depth(inode);
1525 struct ext4_extent *ex;
1529 eh = path[depth].p_hdr;
1530 ex = path[depth].p_ext;
1532 if (unlikely(ex == NULL || eh == NULL)) {
1533 EXT4_ERROR_INODE(inode,
1534 "ex %p == NULL or eh %p == NULL", ex, eh);
1539 /* there is no tree at all */
1543 if (ex != EXT_FIRST_EXTENT(eh)) {
1544 /* we correct tree if first leaf got modified only */
1549 * TODO: we need correction if border is smaller than current one
1552 border = path[depth].p_ext->ee_block;
1553 err = ext4_ext_get_access(handle, inode, path + k);
1556 path[k].p_idx->ei_block = border;
1557 err = ext4_ext_dirty(handle, inode, path + k);
1562 /* change all left-side indexes */
1563 if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
1565 err = ext4_ext_get_access(handle, inode, path + k);
1568 path[k].p_idx->ei_block = border;
1569 err = ext4_ext_dirty(handle, inode, path + k);
1578 ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
1579 struct ext4_extent *ex2)
1581 unsigned short ext1_ee_len, ext2_ee_len, max_len;
1584 * Make sure that both extents are initialized. We don't merge
1585 * uninitialized extents so that we can be sure that end_io code has
1586 * the extent that was written properly split out and conversion to
1587 * initialized is trivial.
1589 if (ext4_ext_is_uninitialized(ex1) || ext4_ext_is_uninitialized(ex2))
1592 if (ext4_ext_is_uninitialized(ex1))
1593 max_len = EXT_UNINIT_MAX_LEN;
1595 max_len = EXT_INIT_MAX_LEN;
1597 ext1_ee_len = ext4_ext_get_actual_len(ex1);
1598 ext2_ee_len = ext4_ext_get_actual_len(ex2);
1600 if (le32_to_cpu(ex1->ee_block) + ext1_ee_len !=
1601 le32_to_cpu(ex2->ee_block))
1605 * To allow future support for preallocated extents to be added
1606 * as an RO_COMPAT feature, refuse to merge to extents if
1607 * this can result in the top bit of ee_len being set.
1609 if (ext1_ee_len + ext2_ee_len > max_len)
1611 #ifdef AGGRESSIVE_TEST
1612 if (ext1_ee_len >= 4)
1616 if (ext4_ext_pblock(ex1) + ext1_ee_len == ext4_ext_pblock(ex2))
1622 * This function tries to merge the "ex" extent to the next extent in the tree.
1623 * It always tries to merge towards right. If you want to merge towards
1624 * left, pass "ex - 1" as argument instead of "ex".
1625 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1626 * 1 if they got merged.
1628 static int ext4_ext_try_to_merge_right(struct inode *inode,
1629 struct ext4_ext_path *path,
1630 struct ext4_extent *ex)
1632 struct ext4_extent_header *eh;
1633 unsigned int depth, len;
1635 int uninitialized = 0;
1637 depth = ext_depth(inode);
1638 BUG_ON(path[depth].p_hdr == NULL);
1639 eh = path[depth].p_hdr;
1641 while (ex < EXT_LAST_EXTENT(eh)) {
1642 if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
1644 /* merge with next extent! */
1645 if (ext4_ext_is_uninitialized(ex))
1647 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1648 + ext4_ext_get_actual_len(ex + 1));
1650 ext4_ext_mark_uninitialized(ex);
1652 if (ex + 1 < EXT_LAST_EXTENT(eh)) {
1653 len = (EXT_LAST_EXTENT(eh) - ex - 1)
1654 * sizeof(struct ext4_extent);
1655 memmove(ex + 1, ex + 2, len);
1657 le16_add_cpu(&eh->eh_entries, -1);
1659 WARN_ON(eh->eh_entries == 0);
1660 if (!eh->eh_entries)
1661 EXT4_ERROR_INODE(inode, "eh->eh_entries = 0!");
1668 * This function does a very simple check to see if we can collapse
1669 * an extent tree with a single extent tree leaf block into the inode.
1671 static void ext4_ext_try_to_merge_up(handle_t *handle,
1672 struct inode *inode,
1673 struct ext4_ext_path *path)
1676 unsigned max_root = ext4_ext_space_root(inode, 0);
1679 if ((path[0].p_depth != 1) ||
1680 (le16_to_cpu(path[0].p_hdr->eh_entries) != 1) ||
1681 (le16_to_cpu(path[1].p_hdr->eh_entries) > max_root))
1685 * We need to modify the block allocation bitmap and the block
1686 * group descriptor to release the extent tree block. If we
1687 * can't get the journal credits, give up.
1689 if (ext4_journal_extend(handle, 2))
1693 * Copy the extent data up to the inode
1695 blk = ext4_idx_pblock(path[0].p_idx);
1696 s = le16_to_cpu(path[1].p_hdr->eh_entries) *
1697 sizeof(struct ext4_extent_idx);
1698 s += sizeof(struct ext4_extent_header);
1700 memcpy(path[0].p_hdr, path[1].p_hdr, s);
1701 path[0].p_depth = 0;
1702 path[0].p_ext = EXT_FIRST_EXTENT(path[0].p_hdr) +
1703 (path[1].p_ext - EXT_FIRST_EXTENT(path[1].p_hdr));
1704 path[0].p_hdr->eh_max = cpu_to_le16(max_root);
1706 brelse(path[1].p_bh);
1707 ext4_free_blocks(handle, inode, NULL, blk, 1,
1708 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
1712 * This function tries to merge the @ex extent to neighbours in the tree.
1713 * return 1 if merge left else 0.
1715 static void ext4_ext_try_to_merge(handle_t *handle,
1716 struct inode *inode,
1717 struct ext4_ext_path *path,
1718 struct ext4_extent *ex) {
1719 struct ext4_extent_header *eh;
1723 depth = ext_depth(inode);
1724 BUG_ON(path[depth].p_hdr == NULL);
1725 eh = path[depth].p_hdr;
1727 if (ex > EXT_FIRST_EXTENT(eh))
1728 merge_done = ext4_ext_try_to_merge_right(inode, path, ex - 1);
1731 (void) ext4_ext_try_to_merge_right(inode, path, ex);
1733 ext4_ext_try_to_merge_up(handle, inode, path);
1737 * check if a portion of the "newext" extent overlaps with an
1740 * If there is an overlap discovered, it updates the length of the newext
1741 * such that there will be no overlap, and then returns 1.
1742 * If there is no overlap found, it returns 0.
1744 static unsigned int ext4_ext_check_overlap(struct ext4_sb_info *sbi,
1745 struct inode *inode,
1746 struct ext4_extent *newext,
1747 struct ext4_ext_path *path)
1750 unsigned int depth, len1;
1751 unsigned int ret = 0;
1753 b1 = le32_to_cpu(newext->ee_block);
1754 len1 = ext4_ext_get_actual_len(newext);
1755 depth = ext_depth(inode);
1756 if (!path[depth].p_ext)
1758 b2 = le32_to_cpu(path[depth].p_ext->ee_block);
1759 b2 &= ~(sbi->s_cluster_ratio - 1);
1762 * get the next allocated block if the extent in the path
1763 * is before the requested block(s)
1766 b2 = ext4_ext_next_allocated_block(path);
1767 if (b2 == EXT_MAX_BLOCKS)
1769 b2 &= ~(sbi->s_cluster_ratio - 1);
1772 /* check for wrap through zero on extent logical start block*/
1773 if (b1 + len1 < b1) {
1774 len1 = EXT_MAX_BLOCKS - b1;
1775 newext->ee_len = cpu_to_le16(len1);
1779 /* check for overlap */
1780 if (b1 + len1 > b2) {
1781 newext->ee_len = cpu_to_le16(b2 - b1);
1789 * ext4_ext_insert_extent:
1790 * tries to merge requsted extent into the existing extent or
1791 * inserts requested extent as new one into the tree,
1792 * creating new leaf in the no-space case.
1794 int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
1795 struct ext4_ext_path *path,
1796 struct ext4_extent *newext, int flag)
1798 struct ext4_extent_header *eh;
1799 struct ext4_extent *ex, *fex;
1800 struct ext4_extent *nearex; /* nearest extent */
1801 struct ext4_ext_path *npath = NULL;
1802 int depth, len, err;
1804 unsigned uninitialized = 0;
1807 if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
1808 EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
1811 depth = ext_depth(inode);
1812 ex = path[depth].p_ext;
1813 eh = path[depth].p_hdr;
1814 if (unlikely(path[depth].p_hdr == NULL)) {
1815 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
1819 /* try to insert block into found extent and return */
1820 if (ex && !(flag & EXT4_GET_BLOCKS_PRE_IO)) {
1823 * Try to see whether we should rather test the extent on
1824 * right from ex, or from the left of ex. This is because
1825 * ext4_ext_find_extent() can return either extent on the
1826 * left, or on the right from the searched position. This
1827 * will make merging more effective.
1829 if (ex < EXT_LAST_EXTENT(eh) &&
1830 (le32_to_cpu(ex->ee_block) +
1831 ext4_ext_get_actual_len(ex) <
1832 le32_to_cpu(newext->ee_block))) {
1835 } else if ((ex > EXT_FIRST_EXTENT(eh)) &&
1836 (le32_to_cpu(newext->ee_block) +
1837 ext4_ext_get_actual_len(newext) <
1838 le32_to_cpu(ex->ee_block)))
1841 /* Try to append newex to the ex */
1842 if (ext4_can_extents_be_merged(inode, ex, newext)) {
1843 ext_debug("append [%d]%d block to %u:[%d]%d"
1845 ext4_ext_is_uninitialized(newext),
1846 ext4_ext_get_actual_len(newext),
1847 le32_to_cpu(ex->ee_block),
1848 ext4_ext_is_uninitialized(ex),
1849 ext4_ext_get_actual_len(ex),
1850 ext4_ext_pblock(ex));
1851 err = ext4_ext_get_access(handle, inode,
1857 * ext4_can_extents_be_merged should have checked
1858 * that either both extents are uninitialized, or
1859 * both aren't. Thus we need to check only one of
1862 if (ext4_ext_is_uninitialized(ex))
1864 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1865 + ext4_ext_get_actual_len(newext));
1867 ext4_ext_mark_uninitialized(ex);
1868 eh = path[depth].p_hdr;
1874 /* Try to prepend newex to the ex */
1875 if (ext4_can_extents_be_merged(inode, newext, ex)) {
1876 ext_debug("prepend %u[%d]%d block to %u:[%d]%d"
1878 le32_to_cpu(newext->ee_block),
1879 ext4_ext_is_uninitialized(newext),
1880 ext4_ext_get_actual_len(newext),
1881 le32_to_cpu(ex->ee_block),
1882 ext4_ext_is_uninitialized(ex),
1883 ext4_ext_get_actual_len(ex),
1884 ext4_ext_pblock(ex));
1885 err = ext4_ext_get_access(handle, inode,
1891 * ext4_can_extents_be_merged should have checked
1892 * that either both extents are uninitialized, or
1893 * both aren't. Thus we need to check only one of
1896 if (ext4_ext_is_uninitialized(ex))
1898 ex->ee_block = newext->ee_block;
1899 ext4_ext_store_pblock(ex, ext4_ext_pblock(newext));
1900 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1901 + ext4_ext_get_actual_len(newext));
1903 ext4_ext_mark_uninitialized(ex);
1904 eh = path[depth].p_hdr;
1910 depth = ext_depth(inode);
1911 eh = path[depth].p_hdr;
1912 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
1915 /* probably next leaf has space for us? */
1916 fex = EXT_LAST_EXTENT(eh);
1917 next = EXT_MAX_BLOCKS;
1918 if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block))
1919 next = ext4_ext_next_leaf_block(path);
1920 if (next != EXT_MAX_BLOCKS) {
1921 ext_debug("next leaf block - %u\n", next);
1922 BUG_ON(npath != NULL);
1923 npath = ext4_ext_find_extent(inode, next, NULL);
1925 return PTR_ERR(npath);
1926 BUG_ON(npath->p_depth != path->p_depth);
1927 eh = npath[depth].p_hdr;
1928 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
1929 ext_debug("next leaf isn't full(%d)\n",
1930 le16_to_cpu(eh->eh_entries));
1934 ext_debug("next leaf has no free space(%d,%d)\n",
1935 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
1939 * There is no free space in the found leaf.
1940 * We're gonna add a new leaf in the tree.
1942 if (flag & EXT4_GET_BLOCKS_METADATA_NOFAIL)
1943 flags = EXT4_MB_USE_RESERVED;
1944 err = ext4_ext_create_new_leaf(handle, inode, flags, path, newext);
1947 depth = ext_depth(inode);
1948 eh = path[depth].p_hdr;
1951 nearex = path[depth].p_ext;
1953 err = ext4_ext_get_access(handle, inode, path + depth);
1958 /* there is no extent in this leaf, create first one */
1959 ext_debug("first extent in the leaf: %u:%llu:[%d]%d\n",
1960 le32_to_cpu(newext->ee_block),
1961 ext4_ext_pblock(newext),
1962 ext4_ext_is_uninitialized(newext),
1963 ext4_ext_get_actual_len(newext));
1964 nearex = EXT_FIRST_EXTENT(eh);
1966 if (le32_to_cpu(newext->ee_block)
1967 > le32_to_cpu(nearex->ee_block)) {
1969 ext_debug("insert %u:%llu:[%d]%d before: "
1971 le32_to_cpu(newext->ee_block),
1972 ext4_ext_pblock(newext),
1973 ext4_ext_is_uninitialized(newext),
1974 ext4_ext_get_actual_len(newext),
1979 BUG_ON(newext->ee_block == nearex->ee_block);
1980 ext_debug("insert %u:%llu:[%d]%d after: "
1982 le32_to_cpu(newext->ee_block),
1983 ext4_ext_pblock(newext),
1984 ext4_ext_is_uninitialized(newext),
1985 ext4_ext_get_actual_len(newext),
1988 len = EXT_LAST_EXTENT(eh) - nearex + 1;
1990 ext_debug("insert %u:%llu:[%d]%d: "
1991 "move %d extents from 0x%p to 0x%p\n",
1992 le32_to_cpu(newext->ee_block),
1993 ext4_ext_pblock(newext),
1994 ext4_ext_is_uninitialized(newext),
1995 ext4_ext_get_actual_len(newext),
1996 len, nearex, nearex + 1);
1997 memmove(nearex + 1, nearex,
1998 len * sizeof(struct ext4_extent));
2002 le16_add_cpu(&eh->eh_entries, 1);
2003 path[depth].p_ext = nearex;
2004 nearex->ee_block = newext->ee_block;
2005 ext4_ext_store_pblock(nearex, ext4_ext_pblock(newext));
2006 nearex->ee_len = newext->ee_len;
2009 /* try to merge extents */
2010 if (!(flag & EXT4_GET_BLOCKS_PRE_IO))
2011 ext4_ext_try_to_merge(handle, inode, path, nearex);
2014 /* time to correct all indexes above */
2015 err = ext4_ext_correct_indexes(handle, inode, path);
2019 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
2023 ext4_ext_drop_refs(npath);
2029 static int ext4_fill_fiemap_extents(struct inode *inode,
2030 ext4_lblk_t block, ext4_lblk_t num,
2031 struct fiemap_extent_info *fieinfo)
2033 struct ext4_ext_path *path = NULL;
2034 struct ext4_extent *ex;
2035 struct extent_status es;
2036 ext4_lblk_t next, next_del, start = 0, end = 0;
2037 ext4_lblk_t last = block + num;
2038 int exists, depth = 0, err = 0;
2039 unsigned int flags = 0;
2040 unsigned char blksize_bits = inode->i_sb->s_blocksize_bits;
2042 while (block < last && block != EXT_MAX_BLOCKS) {
2044 /* find extent for this block */
2045 down_read(&EXT4_I(inode)->i_data_sem);
2047 if (path && ext_depth(inode) != depth) {
2048 /* depth was changed. we have to realloc path */
2053 path = ext4_ext_find_extent(inode, block, path);
2055 up_read(&EXT4_I(inode)->i_data_sem);
2056 err = PTR_ERR(path);
2061 depth = ext_depth(inode);
2062 if (unlikely(path[depth].p_hdr == NULL)) {
2063 up_read(&EXT4_I(inode)->i_data_sem);
2064 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
2068 ex = path[depth].p_ext;
2069 next = ext4_ext_next_allocated_block(path);
2070 ext4_ext_drop_refs(path);
2075 /* there is no extent yet, so try to allocate
2076 * all requested space */
2079 } else if (le32_to_cpu(ex->ee_block) > block) {
2080 /* need to allocate space before found extent */
2082 end = le32_to_cpu(ex->ee_block);
2083 if (block + num < end)
2085 } else if (block >= le32_to_cpu(ex->ee_block)
2086 + ext4_ext_get_actual_len(ex)) {
2087 /* need to allocate space after found extent */
2092 } else if (block >= le32_to_cpu(ex->ee_block)) {
2094 * some part of requested space is covered
2098 end = le32_to_cpu(ex->ee_block)
2099 + ext4_ext_get_actual_len(ex);
2100 if (block + num < end)
2106 BUG_ON(end <= start);
2110 es.es_len = end - start;
2113 es.es_lblk = le32_to_cpu(ex->ee_block);
2114 es.es_len = ext4_ext_get_actual_len(ex);
2115 es.es_pblk = ext4_ext_pblock(ex);
2116 if (ext4_ext_is_uninitialized(ex))
2117 flags |= FIEMAP_EXTENT_UNWRITTEN;
2121 * Find delayed extent and update es accordingly. We call
2122 * it even in !exists case to find out whether es is the
2123 * last existing extent or not.
2125 next_del = ext4_find_delayed_extent(inode, &es);
2126 if (!exists && next_del) {
2128 flags |= FIEMAP_EXTENT_DELALLOC;
2130 up_read(&EXT4_I(inode)->i_data_sem);
2132 if (unlikely(es.es_len == 0)) {
2133 EXT4_ERROR_INODE(inode, "es.es_len == 0");
2139 * This is possible iff next == next_del == EXT_MAX_BLOCKS.
2140 * we need to check next == EXT_MAX_BLOCKS because it is
2141 * possible that an extent is with unwritten and delayed
2142 * status due to when an extent is delayed allocated and
2143 * is allocated by fallocate status tree will track both of
2146 * So we could return a unwritten and delayed extent, and
2147 * its block is equal to 'next'.
2149 if (next == next_del && next == EXT_MAX_BLOCKS) {
2150 flags |= FIEMAP_EXTENT_LAST;
2151 if (unlikely(next_del != EXT_MAX_BLOCKS ||
2152 next != EXT_MAX_BLOCKS)) {
2153 EXT4_ERROR_INODE(inode,
2154 "next extent == %u, next "
2155 "delalloc extent = %u",
2163 err = fiemap_fill_next_extent(fieinfo,
2164 (__u64)es.es_lblk << blksize_bits,
2165 (__u64)es.es_pblk << blksize_bits,
2166 (__u64)es.es_len << blksize_bits,
2176 block = es.es_lblk + es.es_len;
2180 ext4_ext_drop_refs(path);
2188 * ext4_ext_put_gap_in_cache:
2189 * calculate boundaries of the gap that the requested block fits into
2190 * and cache this gap
2193 ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
2196 int depth = ext_depth(inode);
2199 struct ext4_extent *ex;
2201 ex = path[depth].p_ext;
2204 * there is no extent yet, so gap is [0;-] and we
2207 ext_debug("cache gap(whole file):");
2208 } else if (block < le32_to_cpu(ex->ee_block)) {
2210 len = le32_to_cpu(ex->ee_block) - block;
2211 ext_debug("cache gap(before): %u [%u:%u]",
2213 le32_to_cpu(ex->ee_block),
2214 ext4_ext_get_actual_len(ex));
2215 if (!ext4_find_delalloc_range(inode, lblock, lblock + len - 1))
2216 ext4_es_insert_extent(inode, lblock, len, ~0,
2217 EXTENT_STATUS_HOLE);
2218 } else if (block >= le32_to_cpu(ex->ee_block)
2219 + ext4_ext_get_actual_len(ex)) {
2221 lblock = le32_to_cpu(ex->ee_block)
2222 + ext4_ext_get_actual_len(ex);
2224 next = ext4_ext_next_allocated_block(path);
2225 ext_debug("cache gap(after): [%u:%u] %u",
2226 le32_to_cpu(ex->ee_block),
2227 ext4_ext_get_actual_len(ex),
2229 BUG_ON(next == lblock);
2230 len = next - lblock;
2231 if (!ext4_find_delalloc_range(inode, lblock, lblock + len - 1))
2232 ext4_es_insert_extent(inode, lblock, len, ~0,
2233 EXTENT_STATUS_HOLE);
2239 ext_debug(" -> %u:%lu\n", lblock, len);
2244 * removes index from the index block.
2246 static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
2247 struct ext4_ext_path *path, int depth)
2252 /* free index block */
2254 path = path + depth;
2255 leaf = ext4_idx_pblock(path->p_idx);
2256 if (unlikely(path->p_hdr->eh_entries == 0)) {
2257 EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0");
2260 err = ext4_ext_get_access(handle, inode, path);
2264 if (path->p_idx != EXT_LAST_INDEX(path->p_hdr)) {
2265 int len = EXT_LAST_INDEX(path->p_hdr) - path->p_idx;
2266 len *= sizeof(struct ext4_extent_idx);
2267 memmove(path->p_idx, path->p_idx + 1, len);
2270 le16_add_cpu(&path->p_hdr->eh_entries, -1);
2271 err = ext4_ext_dirty(handle, inode, path);
2274 ext_debug("index is empty, remove it, free block %llu\n", leaf);
2275 trace_ext4_ext_rm_idx(inode, leaf);
2277 ext4_free_blocks(handle, inode, NULL, leaf, 1,
2278 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
2280 while (--depth >= 0) {
2281 if (path->p_idx != EXT_FIRST_INDEX(path->p_hdr))
2284 err = ext4_ext_get_access(handle, inode, path);
2287 path->p_idx->ei_block = (path+1)->p_idx->ei_block;
2288 err = ext4_ext_dirty(handle, inode, path);
2296 * ext4_ext_calc_credits_for_single_extent:
2297 * This routine returns max. credits that needed to insert an extent
2298 * to the extent tree.
2299 * When pass the actual path, the caller should calculate credits
2302 int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks,
2303 struct ext4_ext_path *path)
2306 int depth = ext_depth(inode);
2309 /* probably there is space in leaf? */
2310 if (le16_to_cpu(path[depth].p_hdr->eh_entries)
2311 < le16_to_cpu(path[depth].p_hdr->eh_max)) {
2314 * There are some space in the leaf tree, no
2315 * need to account for leaf block credit
2317 * bitmaps and block group descriptor blocks
2318 * and other metadata blocks still need to be
2321 /* 1 bitmap, 1 block group descriptor */
2322 ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb);
2327 return ext4_chunk_trans_blocks(inode, nrblocks);
2331 * How many index/leaf blocks need to change/allocate to modify nrblocks?
2333 * if nrblocks are fit in a single extent (chunk flag is 1), then
2334 * in the worse case, each tree level index/leaf need to be changed
2335 * if the tree split due to insert a new extent, then the old tree
2336 * index/leaf need to be updated too
2338 * If the nrblocks are discontiguous, they could cause
2339 * the whole tree split more than once, but this is really rare.
2341 int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
2346 /* If we are converting the inline data, only one is needed here. */
2347 if (ext4_has_inline_data(inode))
2350 depth = ext_depth(inode);
2360 static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
2361 struct ext4_extent *ex,
2362 long long *partial_cluster,
2363 ext4_lblk_t from, ext4_lblk_t to)
2365 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2366 unsigned short ee_len = ext4_ext_get_actual_len(ex);
2370 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2371 flags |= EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET;
2372 else if (ext4_should_journal_data(inode))
2373 flags |= EXT4_FREE_BLOCKS_FORGET;
2376 * For bigalloc file systems, we never free a partial cluster
2377 * at the beginning of the extent. Instead, we make a note
2378 * that we tried freeing the cluster, and check to see if we
2379 * need to free it on a subsequent call to ext4_remove_blocks,
2380 * or at the end of the ext4_truncate() operation.
2382 flags |= EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER;
2384 trace_ext4_remove_blocks(inode, ex, from, to, *partial_cluster);
2386 * If we have a partial cluster, and it's different from the
2387 * cluster of the last block, we need to explicitly free the
2388 * partial cluster here.
2390 pblk = ext4_ext_pblock(ex) + ee_len - 1;
2391 if ((*partial_cluster > 0) &&
2392 (EXT4_B2C(sbi, pblk) != *partial_cluster)) {
2393 ext4_free_blocks(handle, inode, NULL,
2394 EXT4_C2B(sbi, *partial_cluster),
2395 sbi->s_cluster_ratio, flags);
2396 *partial_cluster = 0;
2399 #ifdef EXTENTS_STATS
2401 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2402 spin_lock(&sbi->s_ext_stats_lock);
2403 sbi->s_ext_blocks += ee_len;
2404 sbi->s_ext_extents++;
2405 if (ee_len < sbi->s_ext_min)
2406 sbi->s_ext_min = ee_len;
2407 if (ee_len > sbi->s_ext_max)
2408 sbi->s_ext_max = ee_len;
2409 if (ext_depth(inode) > sbi->s_depth_max)
2410 sbi->s_depth_max = ext_depth(inode);
2411 spin_unlock(&sbi->s_ext_stats_lock);
2414 if (from >= le32_to_cpu(ex->ee_block)
2415 && to == le32_to_cpu(ex->ee_block) + ee_len - 1) {
2418 unsigned int unaligned;
2420 num = le32_to_cpu(ex->ee_block) + ee_len - from;
2421 pblk = ext4_ext_pblock(ex) + ee_len - num;
2423 * Usually we want to free partial cluster at the end of the
2424 * extent, except for the situation when the cluster is still
2425 * used by any other extent (partial_cluster is negative).
2427 if (*partial_cluster < 0 &&
2428 -(*partial_cluster) == EXT4_B2C(sbi, pblk + num - 1))
2429 flags |= EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER;
2431 ext_debug("free last %u blocks starting %llu partial %lld\n",
2432 num, pblk, *partial_cluster);
2433 ext4_free_blocks(handle, inode, NULL, pblk, num, flags);
2435 * If the block range to be freed didn't start at the
2436 * beginning of a cluster, and we removed the entire
2437 * extent and the cluster is not used by any other extent,
2438 * save the partial cluster here, since we might need to
2439 * delete if we determine that the truncate operation has
2440 * removed all of the blocks in the cluster.
2442 * On the other hand, if we did not manage to free the whole
2443 * extent, we have to mark the cluster as used (store negative
2444 * cluster number in partial_cluster).
2446 unaligned = pblk & (sbi->s_cluster_ratio - 1);
2447 if (unaligned && (ee_len == num) &&
2448 (*partial_cluster != -((long long)EXT4_B2C(sbi, pblk))))
2449 *partial_cluster = EXT4_B2C(sbi, pblk);
2451 *partial_cluster = -((long long)EXT4_B2C(sbi, pblk));
2452 else if (*partial_cluster > 0)
2453 *partial_cluster = 0;
2455 ext4_error(sbi->s_sb, "strange request: removal(2) "
2456 "%u-%u from %u:%u\n",
2457 from, to, le32_to_cpu(ex->ee_block), ee_len);
2463 * ext4_ext_rm_leaf() Removes the extents associated with the
2464 * blocks appearing between "start" and "end", and splits the extents
2465 * if "start" and "end" appear in the same extent
2467 * @handle: The journal handle
2468 * @inode: The files inode
2469 * @path: The path to the leaf
2470 * @partial_cluster: The cluster which we'll have to free if all extents
2471 * has been released from it. It gets negative in case
2472 * that the cluster is still used.
2473 * @start: The first block to remove
2474 * @end: The last block to remove
2477 ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
2478 struct ext4_ext_path *path,
2479 long long *partial_cluster,
2480 ext4_lblk_t start, ext4_lblk_t end)
2482 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2483 int err = 0, correct_index = 0;
2484 int depth = ext_depth(inode), credits;
2485 struct ext4_extent_header *eh;
2488 ext4_lblk_t ex_ee_block;
2489 unsigned short ex_ee_len;
2490 unsigned uninitialized = 0;
2491 struct ext4_extent *ex;
2494 /* the header must be checked already in ext4_ext_remove_space() */
2495 ext_debug("truncate since %u in leaf to %u\n", start, end);
2496 if (!path[depth].p_hdr)
2497 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
2498 eh = path[depth].p_hdr;
2499 if (unlikely(path[depth].p_hdr == NULL)) {
2500 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
2503 /* find where to start removing */
2504 ex = EXT_LAST_EXTENT(eh);
2506 ex_ee_block = le32_to_cpu(ex->ee_block);
2507 ex_ee_len = ext4_ext_get_actual_len(ex);
2509 trace_ext4_ext_rm_leaf(inode, start, ex, *partial_cluster);
2511 while (ex >= EXT_FIRST_EXTENT(eh) &&
2512 ex_ee_block + ex_ee_len > start) {
2514 if (ext4_ext_is_uninitialized(ex))
2519 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block,
2520 uninitialized, ex_ee_len);
2521 path[depth].p_ext = ex;
2523 a = ex_ee_block > start ? ex_ee_block : start;
2524 b = ex_ee_block+ex_ee_len - 1 < end ?
2525 ex_ee_block+ex_ee_len - 1 : end;
2527 ext_debug(" border %u:%u\n", a, b);
2529 /* If this extent is beyond the end of the hole, skip it */
2530 if (end < ex_ee_block) {
2532 * We're going to skip this extent and move to another,
2533 * so if this extent is not cluster aligned we have
2534 * to mark the current cluster as used to avoid
2535 * accidentally freeing it later on
2537 pblk = ext4_ext_pblock(ex);
2538 if (pblk & (sbi->s_cluster_ratio - 1))
2540 -((long long)EXT4_B2C(sbi, pblk));
2542 ex_ee_block = le32_to_cpu(ex->ee_block);
2543 ex_ee_len = ext4_ext_get_actual_len(ex);
2545 } else if (b != ex_ee_block + ex_ee_len - 1) {
2546 EXT4_ERROR_INODE(inode,
2547 "can not handle truncate %u:%u "
2549 start, end, ex_ee_block,
2550 ex_ee_block + ex_ee_len - 1);
2553 } else if (a != ex_ee_block) {
2554 /* remove tail of the extent */
2555 num = a - ex_ee_block;
2557 /* remove whole extent: excellent! */
2561 * 3 for leaf, sb, and inode plus 2 (bmap and group
2562 * descriptor) for each block group; assume two block
2563 * groups plus ex_ee_len/blocks_per_block_group for
2566 credits = 7 + 2*(ex_ee_len/EXT4_BLOCKS_PER_GROUP(inode->i_sb));
2567 if (ex == EXT_FIRST_EXTENT(eh)) {
2569 credits += (ext_depth(inode)) + 1;
2571 credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
2573 err = ext4_ext_truncate_extend_restart(handle, inode, credits);
2577 err = ext4_ext_get_access(handle, inode, path + depth);
2581 err = ext4_remove_blocks(handle, inode, ex, partial_cluster,
2587 /* this extent is removed; mark slot entirely unused */
2588 ext4_ext_store_pblock(ex, 0);
2590 ex->ee_len = cpu_to_le16(num);
2592 * Do not mark uninitialized if all the blocks in the
2593 * extent have been removed.
2595 if (uninitialized && num)
2596 ext4_ext_mark_uninitialized(ex);
2598 * If the extent was completely released,
2599 * we need to remove it from the leaf
2602 if (end != EXT_MAX_BLOCKS - 1) {
2604 * For hole punching, we need to scoot all the
2605 * extents up when an extent is removed so that
2606 * we dont have blank extents in the middle
2608 memmove(ex, ex+1, (EXT_LAST_EXTENT(eh) - ex) *
2609 sizeof(struct ext4_extent));
2611 /* Now get rid of the one at the end */
2612 memset(EXT_LAST_EXTENT(eh), 0,
2613 sizeof(struct ext4_extent));
2615 le16_add_cpu(&eh->eh_entries, -1);
2616 } else if (*partial_cluster > 0)
2617 *partial_cluster = 0;
2619 err = ext4_ext_dirty(handle, inode, path + depth);
2623 ext_debug("new extent: %u:%u:%llu\n", ex_ee_block, num,
2624 ext4_ext_pblock(ex));
2626 ex_ee_block = le32_to_cpu(ex->ee_block);
2627 ex_ee_len = ext4_ext_get_actual_len(ex);
2630 if (correct_index && eh->eh_entries)
2631 err = ext4_ext_correct_indexes(handle, inode, path);
2634 * Free the partial cluster only if the current extent does not
2635 * reference it. Otherwise we might free used cluster.
2637 if (*partial_cluster > 0 &&
2638 (EXT4_B2C(sbi, ext4_ext_pblock(ex) + ex_ee_len - 1) !=
2639 *partial_cluster)) {
2640 int flags = EXT4_FREE_BLOCKS_FORGET;
2642 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2643 flags |= EXT4_FREE_BLOCKS_METADATA;
2645 ext4_free_blocks(handle, inode, NULL,
2646 EXT4_C2B(sbi, *partial_cluster),
2647 sbi->s_cluster_ratio, flags);
2648 *partial_cluster = 0;
2651 /* if this leaf is free, then we should
2652 * remove it from index block above */
2653 if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
2654 err = ext4_ext_rm_idx(handle, inode, path, depth);
2661 * ext4_ext_more_to_rm:
2662 * returns 1 if current index has to be freed (even partial)
2665 ext4_ext_more_to_rm(struct ext4_ext_path *path)
2667 BUG_ON(path->p_idx == NULL);
2669 if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
2673 * if truncate on deeper level happened, it wasn't partial,
2674 * so we have to consider current index for truncation
2676 if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
2681 int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2684 struct super_block *sb = inode->i_sb;
2685 int depth = ext_depth(inode);
2686 struct ext4_ext_path *path = NULL;
2687 long long partial_cluster = 0;
2691 ext_debug("truncate since %u to %u\n", start, end);
2693 /* probably first extent we're gonna free will be last in block */
2694 handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, depth + 1);
2696 return PTR_ERR(handle);
2699 trace_ext4_ext_remove_space(inode, start, end, depth);
2702 * Check if we are removing extents inside the extent tree. If that
2703 * is the case, we are going to punch a hole inside the extent tree
2704 * so we have to check whether we need to split the extent covering
2705 * the last block to remove so we can easily remove the part of it
2706 * in ext4_ext_rm_leaf().
2708 if (end < EXT_MAX_BLOCKS - 1) {
2709 struct ext4_extent *ex;
2710 ext4_lblk_t ee_block;
2712 /* find extent for this block */
2713 path = ext4_ext_find_extent(inode, end, NULL);
2715 ext4_journal_stop(handle);
2716 return PTR_ERR(path);
2718 depth = ext_depth(inode);
2719 /* Leaf not may not exist only if inode has no blocks at all */
2720 ex = path[depth].p_ext;
2723 EXT4_ERROR_INODE(inode,
2724 "path[%d].p_hdr == NULL",
2731 ee_block = le32_to_cpu(ex->ee_block);
2734 * See if the last block is inside the extent, if so split
2735 * the extent at 'end' block so we can easily remove the
2736 * tail of the first part of the split extent in
2737 * ext4_ext_rm_leaf().
2739 if (end >= ee_block &&
2740 end < ee_block + ext4_ext_get_actual_len(ex) - 1) {
2743 if (ext4_ext_is_uninitialized(ex))
2744 split_flag = EXT4_EXT_MARK_UNINIT1 |
2745 EXT4_EXT_MARK_UNINIT2;
2748 * Split the extent in two so that 'end' is the last
2749 * block in the first new extent. Also we should not
2750 * fail removing space due to ENOSPC so try to use
2751 * reserved block if that happens.
2753 err = ext4_split_extent_at(handle, inode, path,
2754 end + 1, split_flag,
2755 EXT4_GET_BLOCKS_PRE_IO |
2756 EXT4_GET_BLOCKS_METADATA_NOFAIL);
2763 * We start scanning from right side, freeing all the blocks
2764 * after i_size and walking into the tree depth-wise.
2766 depth = ext_depth(inode);
2771 le16_to_cpu(path[k].p_hdr->eh_entries)+1;
2773 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1),
2776 ext4_journal_stop(handle);
2779 path[0].p_depth = depth;
2780 path[0].p_hdr = ext_inode_hdr(inode);
2783 if (ext4_ext_check(inode, path[0].p_hdr, depth)) {
2790 while (i >= 0 && err == 0) {
2792 /* this is leaf block */
2793 err = ext4_ext_rm_leaf(handle, inode, path,
2794 &partial_cluster, start,
2796 /* root level has p_bh == NULL, brelse() eats this */
2797 brelse(path[i].p_bh);
2798 path[i].p_bh = NULL;
2803 /* this is index block */
2804 if (!path[i].p_hdr) {
2805 ext_debug("initialize header\n");
2806 path[i].p_hdr = ext_block_hdr(path[i].p_bh);
2809 if (!path[i].p_idx) {
2810 /* this level hasn't been touched yet */
2811 path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
2812 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
2813 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2815 le16_to_cpu(path[i].p_hdr->eh_entries));
2817 /* we were already here, see at next index */
2821 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2822 i, EXT_FIRST_INDEX(path[i].p_hdr),
2824 if (ext4_ext_more_to_rm(path + i)) {
2825 struct buffer_head *bh;
2826 /* go to the next level */
2827 ext_debug("move to level %d (block %llu)\n",
2828 i + 1, ext4_idx_pblock(path[i].p_idx));
2829 memset(path + i + 1, 0, sizeof(*path));
2830 bh = sb_bread(sb, ext4_idx_pblock(path[i].p_idx));
2832 /* should we reset i_size? */
2836 if (WARN_ON(i + 1 > depth)) {
2840 if (ext4_ext_check_block(inode, ext_block_hdr(bh),
2841 depth - i - 1, bh)) {
2845 path[i + 1].p_bh = bh;
2847 /* save actual number of indexes since this
2848 * number is changed at the next iteration */
2849 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
2852 /* we finished processing this index, go up */
2853 if (path[i].p_hdr->eh_entries == 0 && i > 0) {
2854 /* index is empty, remove it;
2855 * handle must be already prepared by the
2856 * truncatei_leaf() */
2857 err = ext4_ext_rm_idx(handle, inode, path, i);
2859 /* root level has p_bh == NULL, brelse() eats this */
2860 brelse(path[i].p_bh);
2861 path[i].p_bh = NULL;
2863 ext_debug("return to level %d\n", i);
2867 trace_ext4_ext_remove_space_done(inode, start, end, depth,
2868 partial_cluster, path->p_hdr->eh_entries);
2870 /* If we still have something in the partial cluster and we have removed
2871 * even the first extent, then we should free the blocks in the partial
2872 * cluster as well. */
2873 if (partial_cluster > 0 && path->p_hdr->eh_entries == 0) {
2874 int flags = EXT4_FREE_BLOCKS_FORGET;
2876 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2877 flags |= EXT4_FREE_BLOCKS_METADATA;
2879 ext4_free_blocks(handle, inode, NULL,
2880 EXT4_C2B(EXT4_SB(sb), partial_cluster),
2881 EXT4_SB(sb)->s_cluster_ratio, flags);
2882 partial_cluster = 0;
2885 /* TODO: flexible tree reduction should be here */
2886 if (path->p_hdr->eh_entries == 0) {
2888 * truncate to zero freed all the tree,
2889 * so we need to correct eh_depth
2891 err = ext4_ext_get_access(handle, inode, path);
2893 ext_inode_hdr(inode)->eh_depth = 0;
2894 ext_inode_hdr(inode)->eh_max =
2895 cpu_to_le16(ext4_ext_space_root(inode, 0));
2896 err = ext4_ext_dirty(handle, inode, path);
2900 ext4_ext_drop_refs(path);
2902 if (err == -EAGAIN) {
2906 ext4_journal_stop(handle);
2912 * called at mount time
2914 void ext4_ext_init(struct super_block *sb)
2917 * possible initialization would be here
2920 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2921 #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
2922 printk(KERN_INFO "EXT4-fs: file extents enabled"
2923 #ifdef AGGRESSIVE_TEST
2924 ", aggressive tests"
2926 #ifdef CHECK_BINSEARCH
2929 #ifdef EXTENTS_STATS
2934 #ifdef EXTENTS_STATS
2935 spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
2936 EXT4_SB(sb)->s_ext_min = 1 << 30;
2937 EXT4_SB(sb)->s_ext_max = 0;
2943 * called at umount time
2945 void ext4_ext_release(struct super_block *sb)
2947 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2950 #ifdef EXTENTS_STATS
2951 if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
2952 struct ext4_sb_info *sbi = EXT4_SB(sb);
2953 printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2954 sbi->s_ext_blocks, sbi->s_ext_extents,
2955 sbi->s_ext_blocks / sbi->s_ext_extents);
2956 printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2957 sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
2962 /* FIXME!! we need to try to merge to left or right after zero-out */
2963 static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
2965 ext4_fsblk_t ee_pblock;
2966 unsigned int ee_len;
2969 ee_len = ext4_ext_get_actual_len(ex);
2970 ee_pblock = ext4_ext_pblock(ex);
2972 ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
2980 * ext4_split_extent_at() splits an extent at given block.
2982 * @handle: the journal handle
2983 * @inode: the file inode
2984 * @path: the path to the extent
2985 * @split: the logical block where the extent is splitted.
2986 * @split_flags: indicates if the extent could be zeroout if split fails, and
2987 * the states(init or uninit) of new extents.
2988 * @flags: flags used to insert new extent to extent tree.
2991 * Splits extent [a, b] into two extents [a, @split) and [@split, b], states
2992 * of which are deterimined by split_flag.
2994 * There are two cases:
2995 * a> the extent are splitted into two extent.
2996 * b> split is not needed, and just mark the extent.
2998 * return 0 on success.
3000 static int ext4_split_extent_at(handle_t *handle,
3001 struct inode *inode,
3002 struct ext4_ext_path *path,
3007 ext4_fsblk_t newblock;
3008 ext4_lblk_t ee_block;
3009 struct ext4_extent *ex, newex, orig_ex, zero_ex;
3010 struct ext4_extent *ex2 = NULL;
3011 unsigned int ee_len, depth;
3014 BUG_ON((split_flag & (EXT4_EXT_DATA_VALID1 | EXT4_EXT_DATA_VALID2)) ==
3015 (EXT4_EXT_DATA_VALID1 | EXT4_EXT_DATA_VALID2));
3017 ext_debug("ext4_split_extents_at: inode %lu, logical"
3018 "block %llu\n", inode->i_ino, (unsigned long long)split);
3020 ext4_ext_show_leaf(inode, path);
3022 depth = ext_depth(inode);
3023 ex = path[depth].p_ext;
3024 ee_block = le32_to_cpu(ex->ee_block);
3025 ee_len = ext4_ext_get_actual_len(ex);
3026 newblock = split - ee_block + ext4_ext_pblock(ex);
3028 BUG_ON(split < ee_block || split >= (ee_block + ee_len));
3029 BUG_ON(!ext4_ext_is_uninitialized(ex) &&
3030 split_flag & (EXT4_EXT_MAY_ZEROOUT |
3031 EXT4_EXT_MARK_UNINIT1 |
3032 EXT4_EXT_MARK_UNINIT2));
3034 err = ext4_ext_get_access(handle, inode, path + depth);
3038 if (split == ee_block) {
3040 * case b: block @split is the block that the extent begins with
3041 * then we just change the state of the extent, and splitting
3044 if (split_flag & EXT4_EXT_MARK_UNINIT2)
3045 ext4_ext_mark_uninitialized(ex);
3047 ext4_ext_mark_initialized(ex);
3049 if (!(flags & EXT4_GET_BLOCKS_PRE_IO))
3050 ext4_ext_try_to_merge(handle, inode, path, ex);
3052 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
3057 memcpy(&orig_ex, ex, sizeof(orig_ex));
3058 ex->ee_len = cpu_to_le16(split - ee_block);
3059 if (split_flag & EXT4_EXT_MARK_UNINIT1)
3060 ext4_ext_mark_uninitialized(ex);
3063 * path may lead to new leaf, not to original leaf any more
3064 * after ext4_ext_insert_extent() returns,
3066 err = ext4_ext_dirty(handle, inode, path + depth);
3068 goto fix_extent_len;
3071 ex2->ee_block = cpu_to_le32(split);
3072 ex2->ee_len = cpu_to_le16(ee_len - (split - ee_block));
3073 ext4_ext_store_pblock(ex2, newblock);
3074 if (split_flag & EXT4_EXT_MARK_UNINIT2)
3075 ext4_ext_mark_uninitialized(ex2);
3077 err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
3078 if (err == -ENOSPC && (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
3079 if (split_flag & (EXT4_EXT_DATA_VALID1|EXT4_EXT_DATA_VALID2)) {
3080 if (split_flag & EXT4_EXT_DATA_VALID1) {
3081 err = ext4_ext_zeroout(inode, ex2);
3082 zero_ex.ee_block = ex2->ee_block;
3083 zero_ex.ee_len = cpu_to_le16(
3084 ext4_ext_get_actual_len(ex2));
3085 ext4_ext_store_pblock(&zero_ex,
3086 ext4_ext_pblock(ex2));
3088 err = ext4_ext_zeroout(inode, ex);
3089 zero_ex.ee_block = ex->ee_block;
3090 zero_ex.ee_len = cpu_to_le16(
3091 ext4_ext_get_actual_len(ex));
3092 ext4_ext_store_pblock(&zero_ex,
3093 ext4_ext_pblock(ex));
3096 err = ext4_ext_zeroout(inode, &orig_ex);
3097 zero_ex.ee_block = orig_ex.ee_block;
3098 zero_ex.ee_len = cpu_to_le16(
3099 ext4_ext_get_actual_len(&orig_ex));
3100 ext4_ext_store_pblock(&zero_ex,
3101 ext4_ext_pblock(&orig_ex));
3105 goto fix_extent_len;
3106 /* update the extent length and mark as initialized */
3107 ex->ee_len = cpu_to_le16(ee_len);
3108 ext4_ext_try_to_merge(handle, inode, path, ex);
3109 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
3111 goto fix_extent_len;
3113 /* update extent status tree */
3114 err = ext4_es_zeroout(inode, &zero_ex);
3118 goto fix_extent_len;
3121 ext4_ext_show_leaf(inode, path);
3125 ex->ee_len = orig_ex.ee_len;
3126 ext4_ext_dirty(handle, inode, path + depth);
3131 * ext4_split_extents() splits an extent and mark extent which is covered
3132 * by @map as split_flags indicates
3134 * It may result in splitting the extent into multiple extents (upto three)
3135 * There are three possibilities:
3136 * a> There is no split required
3137 * b> Splits in two extents: Split is happening at either end of the extent
3138 * c> Splits in three extents: Somone is splitting in middle of the extent
3141 static int ext4_split_extent(handle_t *handle,
3142 struct inode *inode,
3143 struct ext4_ext_path *path,
3144 struct ext4_map_blocks *map,
3148 ext4_lblk_t ee_block;
3149 struct ext4_extent *ex;
3150 unsigned int ee_len, depth;
3153 int split_flag1, flags1;
3154 int allocated = map->m_len;
3156 depth = ext_depth(inode);
3157 ex = path[depth].p_ext;
3158 ee_block = le32_to_cpu(ex->ee_block);
3159 ee_len = ext4_ext_get_actual_len(ex);
3160 uninitialized = ext4_ext_is_uninitialized(ex);
3162 if (map->m_lblk + map->m_len < ee_block + ee_len) {
3163 split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT;
3164 flags1 = flags | EXT4_GET_BLOCKS_PRE_IO;
3166 split_flag1 |= EXT4_EXT_MARK_UNINIT1 |
3167 EXT4_EXT_MARK_UNINIT2;
3168 if (split_flag & EXT4_EXT_DATA_VALID2)
3169 split_flag1 |= EXT4_EXT_DATA_VALID1;
3170 err = ext4_split_extent_at(handle, inode, path,
3171 map->m_lblk + map->m_len, split_flag1, flags1);
3175 allocated = ee_len - (map->m_lblk - ee_block);
3178 * Update path is required because previous ext4_split_extent_at() may
3179 * result in split of original leaf or extent zeroout.
3181 ext4_ext_drop_refs(path);
3182 path = ext4_ext_find_extent(inode, map->m_lblk, path);
3184 return PTR_ERR(path);
3185 depth = ext_depth(inode);
3186 ex = path[depth].p_ext;
3187 uninitialized = ext4_ext_is_uninitialized(ex);
3190 if (map->m_lblk >= ee_block) {
3191 split_flag1 = split_flag & EXT4_EXT_DATA_VALID2;
3192 if (uninitialized) {
3193 split_flag1 |= EXT4_EXT_MARK_UNINIT1;
3194 split_flag1 |= split_flag & (EXT4_EXT_MAY_ZEROOUT |
3195 EXT4_EXT_MARK_UNINIT2);
3197 err = ext4_split_extent_at(handle, inode, path,
3198 map->m_lblk, split_flag1, flags);
3203 ext4_ext_show_leaf(inode, path);
3205 return err ? err : allocated;
3209 * This function is called by ext4_ext_map_blocks() if someone tries to write
3210 * to an uninitialized extent. It may result in splitting the uninitialized
3211 * extent into multiple extents (up to three - one initialized and two
3213 * There are three possibilities:
3214 * a> There is no split required: Entire extent should be initialized
3215 * b> Splits in two extents: Write is happening at either end of the extent
3216 * c> Splits in three extents: Somone is writing in middle of the extent
3219 * - The extent pointed to by 'path' is uninitialized.
3220 * - The extent pointed to by 'path' contains a superset
3221 * of the logical span [map->m_lblk, map->m_lblk + map->m_len).
3223 * Post-conditions on success:
3224 * - the returned value is the number of blocks beyond map->l_lblk
3225 * that are allocated and initialized.
3226 * It is guaranteed to be >= map->m_len.
3228 static int ext4_ext_convert_to_initialized(handle_t *handle,
3229 struct inode *inode,
3230 struct ext4_map_blocks *map,
3231 struct ext4_ext_path *path,
3234 struct ext4_sb_info *sbi;
3235 struct ext4_extent_header *eh;
3236 struct ext4_map_blocks split_map;
3237 struct ext4_extent zero_ex;
3238 struct ext4_extent *ex, *abut_ex;
3239 ext4_lblk_t ee_block, eof_block;
3240 unsigned int ee_len, depth, map_len = map->m_len;
3241 int allocated = 0, max_zeroout = 0;
3245 ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
3246 "block %llu, max_blocks %u\n", inode->i_ino,
3247 (unsigned long long)map->m_lblk, map_len);
3249 sbi = EXT4_SB(inode->i_sb);
3250 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
3251 inode->i_sb->s_blocksize_bits;
3252 if (eof_block < map->m_lblk + map_len)
3253 eof_block = map->m_lblk + map_len;
3255 depth = ext_depth(inode);
3256 eh = path[depth].p_hdr;
3257 ex = path[depth].p_ext;
3258 ee_block = le32_to_cpu(ex->ee_block);
3259 ee_len = ext4_ext_get_actual_len(ex);
3262 trace_ext4_ext_convert_to_initialized_enter(inode, map, ex);
3264 /* Pre-conditions */
3265 BUG_ON(!ext4_ext_is_uninitialized(ex));
3266 BUG_ON(!in_range(map->m_lblk, ee_block, ee_len));
3269 * Attempt to transfer newly initialized blocks from the currently
3270 * uninitialized extent to its neighbor. This is much cheaper
3271 * than an insertion followed by a merge as those involve costly
3272 * memmove() calls. Transferring to the left is the common case in
3273 * steady state for workloads doing fallocate(FALLOC_FL_KEEP_SIZE)
3274 * followed by append writes.
3276 * Limitations of the current logic:
3277 * - L1: we do not deal with writes covering the whole extent.
3278 * This would require removing the extent if the transfer
3280 * - L2: we only attempt to merge with an extent stored in the
3281 * same extent tree node.
3283 if ((map->m_lblk == ee_block) &&
3284 /* See if we can merge left */
3285 (map_len < ee_len) && /*L1*/
3286 (ex > EXT_FIRST_EXTENT(eh))) { /*L2*/
3287 ext4_lblk_t prev_lblk;
3288 ext4_fsblk_t prev_pblk, ee_pblk;
3289 unsigned int prev_len;
3292 prev_lblk = le32_to_cpu(abut_ex->ee_block);
3293 prev_len = ext4_ext_get_actual_len(abut_ex);
3294 prev_pblk = ext4_ext_pblock(abut_ex);
3295 ee_pblk = ext4_ext_pblock(ex);
3298 * A transfer of blocks from 'ex' to 'abut_ex' is allowed
3299 * upon those conditions:
3300 * - C1: abut_ex is initialized,
3301 * - C2: abut_ex is logically abutting ex,
3302 * - C3: abut_ex is physically abutting ex,
3303 * - C4: abut_ex can receive the additional blocks without
3304 * overflowing the (initialized) length limit.
3306 if ((!ext4_ext_is_uninitialized(abut_ex)) && /*C1*/
3307 ((prev_lblk + prev_len) == ee_block) && /*C2*/
3308 ((prev_pblk + prev_len) == ee_pblk) && /*C3*/
3309 (prev_len < (EXT_INIT_MAX_LEN - map_len))) { /*C4*/
3310 err = ext4_ext_get_access(handle, inode, path + depth);
3314 trace_ext4_ext_convert_to_initialized_fastpath(inode,
3317 /* Shift the start of ex by 'map_len' blocks */
3318 ex->ee_block = cpu_to_le32(ee_block + map_len);
3319 ext4_ext_store_pblock(ex, ee_pblk + map_len);
3320 ex->ee_len = cpu_to_le16(ee_len - map_len);
3321 ext4_ext_mark_uninitialized(ex); /* Restore the flag */
3323 /* Extend abut_ex by 'map_len' blocks */
3324 abut_ex->ee_len = cpu_to_le16(prev_len + map_len);
3326 /* Result: number of initialized blocks past m_lblk */
3327 allocated = map_len;
3329 } else if (((map->m_lblk + map_len) == (ee_block + ee_len)) &&
3330 (map_len < ee_len) && /*L1*/
3331 ex < EXT_LAST_EXTENT(eh)) { /*L2*/
3332 /* See if we can merge right */
3333 ext4_lblk_t next_lblk;
3334 ext4_fsblk_t next_pblk, ee_pblk;
3335 unsigned int next_len;
3338 next_lblk = le32_to_cpu(abut_ex->ee_block);
3339 next_len = ext4_ext_get_actual_len(abut_ex);
3340 next_pblk = ext4_ext_pblock(abut_ex);
3341 ee_pblk = ext4_ext_pblock(ex);
3344 * A transfer of blocks from 'ex' to 'abut_ex' is allowed
3345 * upon those conditions:
3346 * - C1: abut_ex is initialized,
3347 * - C2: abut_ex is logically abutting ex,
3348 * - C3: abut_ex is physically abutting ex,
3349 * - C4: abut_ex can receive the additional blocks without
3350 * overflowing the (initialized) length limit.
3352 if ((!ext4_ext_is_uninitialized(abut_ex)) && /*C1*/
3353 ((map->m_lblk + map_len) == next_lblk) && /*C2*/
3354 ((ee_pblk + ee_len) == next_pblk) && /*C3*/
3355 (next_len < (EXT_INIT_MAX_LEN - map_len))) { /*C4*/
3356 err = ext4_ext_get_access(handle, inode, path + depth);
3360 trace_ext4_ext_convert_to_initialized_fastpath(inode,
3363 /* Shift the start of abut_ex by 'map_len' blocks */
3364 abut_ex->ee_block = cpu_to_le32(next_lblk - map_len);
3365 ext4_ext_store_pblock(abut_ex, next_pblk - map_len);
3366 ex->ee_len = cpu_to_le16(ee_len - map_len);
3367 ext4_ext_mark_uninitialized(ex); /* Restore the flag */
3369 /* Extend abut_ex by 'map_len' blocks */
3370 abut_ex->ee_len = cpu_to_le16(next_len + map_len);
3372 /* Result: number of initialized blocks past m_lblk */
3373 allocated = map_len;
3377 /* Mark the block containing both extents as dirty */
3378 ext4_ext_dirty(handle, inode, path + depth);
3380 /* Update path to point to the right extent */
3381 path[depth].p_ext = abut_ex;
3384 allocated = ee_len - (map->m_lblk - ee_block);
3386 WARN_ON(map->m_lblk < ee_block);
3388 * It is safe to convert extent to initialized via explicit
3389 * zeroout only if extent is fully insde i_size or new_size.
3391 split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
3393 if (EXT4_EXT_MAY_ZEROOUT & split_flag)
3394 max_zeroout = sbi->s_extent_max_zeroout_kb >>
3395 (inode->i_sb->s_blocksize_bits - 10);
3397 /* If extent is less than s_max_zeroout_kb, zeroout directly */
3398 if (max_zeroout && (ee_len <= max_zeroout)) {
3399 err = ext4_ext_zeroout(inode, ex);
3402 zero_ex.ee_block = ex->ee_block;
3403 zero_ex.ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex));
3404 ext4_ext_store_pblock(&zero_ex, ext4_ext_pblock(ex));
3406 err = ext4_ext_get_access(handle, inode, path + depth);
3409 ext4_ext_mark_initialized(ex);
3410 ext4_ext_try_to_merge(handle, inode, path, ex);
3411 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
3417 * 1. split the extent into three extents.
3418 * 2. split the extent into two extents, zeroout the first half.
3419 * 3. split the extent into two extents, zeroout the second half.
3420 * 4. split the extent into two extents with out zeroout.
3422 split_map.m_lblk = map->m_lblk;
3423 split_map.m_len = map->m_len;
3425 if (max_zeroout && (allocated > map->m_len)) {
3426 if (allocated <= max_zeroout) {
3429 cpu_to_le32(map->m_lblk);
3430 zero_ex.ee_len = cpu_to_le16(allocated);
3431 ext4_ext_store_pblock(&zero_ex,
3432 ext4_ext_pblock(ex) + map->m_lblk - ee_block);
3433 err = ext4_ext_zeroout(inode, &zero_ex);
3436 split_map.m_lblk = map->m_lblk;
3437 split_map.m_len = allocated;
3438 } else if (map->m_lblk - ee_block + map->m_len < max_zeroout) {
3440 if (map->m_lblk != ee_block) {
3441 zero_ex.ee_block = ex->ee_block;
3442 zero_ex.ee_len = cpu_to_le16(map->m_lblk -
3444 ext4_ext_store_pblock(&zero_ex,
3445 ext4_ext_pblock(ex));
3446 err = ext4_ext_zeroout(inode, &zero_ex);
3451 split_map.m_lblk = ee_block;
3452 split_map.m_len = map->m_lblk - ee_block + map->m_len;
3453 allocated = map->m_len;
3457 allocated = ext4_split_extent(handle, inode, path,
3458 &split_map, split_flag, flags);
3463 /* If we have gotten a failure, don't zero out status tree */
3465 err = ext4_es_zeroout(inode, &zero_ex);
3466 return err ? err : allocated;
3470 * This function is called by ext4_ext_map_blocks() from
3471 * ext4_get_blocks_dio_write() when DIO to write
3472 * to an uninitialized extent.
3474 * Writing to an uninitialized extent may result in splitting the uninitialized
3475 * extent into multiple initialized/uninitialized extents (up to three)
3476 * There are three possibilities:
3477 * a> There is no split required: Entire extent should be uninitialized
3478 * b> Splits in two extents: Write is happening at either end of the extent
3479 * c> Splits in three extents: Somone is writing in middle of the extent
3481 * One of more index blocks maybe needed if the extent tree grow after
3482 * the uninitialized extent split. To prevent ENOSPC occur at the IO
3483 * complete, we need to split the uninitialized extent before DIO submit
3484 * the IO. The uninitialized extent called at this time will be split
3485 * into three uninitialized extent(at most). After IO complete, the part
3486 * being filled will be convert to initialized by the end_io callback function
3487 * via ext4_convert_unwritten_extents().
3489 * Returns the size of uninitialized extent to be written on success.
3491 static int ext4_split_unwritten_extents(handle_t *handle,
3492 struct inode *inode,
3493 struct ext4_map_blocks *map,
3494 struct ext4_ext_path *path,
3497 ext4_lblk_t eof_block;
3498 ext4_lblk_t ee_block;
3499 struct ext4_extent *ex;
3500 unsigned int ee_len;
3501 int split_flag = 0, depth;
3503 ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
3504 "block %llu, max_blocks %u\n", inode->i_ino,
3505 (unsigned long long)map->m_lblk, map->m_len);
3507 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
3508 inode->i_sb->s_blocksize_bits;
3509 if (eof_block < map->m_lblk + map->m_len)
3510 eof_block = map->m_lblk + map->m_len;
3512 * It is safe to convert extent to initialized via explicit
3513 * zeroout only if extent is fully insde i_size or new_size.
3515 depth = ext_depth(inode);
3516 ex = path[depth].p_ext;
3517 ee_block = le32_to_cpu(ex->ee_block);
3518 ee_len = ext4_ext_get_actual_len(ex);
3520 split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
3521 split_flag |= EXT4_EXT_MARK_UNINIT2;
3522 if (flags & EXT4_GET_BLOCKS_CONVERT)
3523 split_flag |= EXT4_EXT_DATA_VALID2;
3524 flags |= EXT4_GET_BLOCKS_PRE_IO;
3525 return ext4_split_extent(handle, inode, path, map, split_flag, flags);
3528 static int ext4_convert_unwritten_extents_endio(handle_t *handle,
3529 struct inode *inode,
3530 struct ext4_map_blocks *map,
3531 struct ext4_ext_path *path)
3533 struct ext4_extent *ex;
3534 ext4_lblk_t ee_block;
3535 unsigned int ee_len;
3539 depth = ext_depth(inode);
3540 ex = path[depth].p_ext;
3541 ee_block = le32_to_cpu(ex->ee_block);
3542 ee_len = ext4_ext_get_actual_len(ex);
3544 ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical"
3545 "block %llu, max_blocks %u\n", inode->i_ino,
3546 (unsigned long long)ee_block, ee_len);
3548 /* If extent is larger than requested it is a clear sign that we still
3549 * have some extent state machine issues left. So extent_split is still
3551 * TODO: Once all related issues will be fixed this situation should be
3554 if (ee_block != map->m_lblk || ee_len > map->m_len) {
3556 ext4_warning("Inode (%ld) finished: extent logical block %llu,"
3557 " len %u; IO logical block %llu, len %u\n",
3558 inode->i_ino, (unsigned long long)ee_block, ee_len,
3559 (unsigned long long)map->m_lblk, map->m_len);
3561 err = ext4_split_unwritten_extents(handle, inode, map, path,
3562 EXT4_GET_BLOCKS_CONVERT);
3565 ext4_ext_drop_refs(path);
3566 path = ext4_ext_find_extent(inode, map->m_lblk, path);
3568 err = PTR_ERR(path);
3571 depth = ext_depth(inode);
3572 ex = path[depth].p_ext;
3575 err = ext4_ext_get_access(handle, inode, path + depth);
3578 /* first mark the extent as initialized */
3579 ext4_ext_mark_initialized(ex);
3581 /* note: ext4_ext_correct_indexes() isn't needed here because
3582 * borders are not changed
3584 ext4_ext_try_to_merge(handle, inode, path, ex);
3586 /* Mark modified extent as dirty */
3587 err = ext4_ext_dirty(handle, inode, path + path->p_depth);
3589 ext4_ext_show_leaf(inode, path);
3593 static void unmap_underlying_metadata_blocks(struct block_device *bdev,
3594 sector_t block, int count)
3597 for (i = 0; i < count; i++)
3598 unmap_underlying_metadata(bdev, block + i);
3602 * Handle EOFBLOCKS_FL flag, clearing it if necessary
3604 static int check_eofblocks_fl(handle_t *handle, struct inode *inode,
3606 struct ext4_ext_path *path,
3610 struct ext4_extent_header *eh;
3611 struct ext4_extent *last_ex;
3613 if (!ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
3616 depth = ext_depth(inode);
3617 eh = path[depth].p_hdr;
3620 * We're going to remove EOFBLOCKS_FL entirely in future so we
3621 * do not care for this case anymore. Simply remove the flag
3622 * if there are no extents.
3624 if (unlikely(!eh->eh_entries))
3626 last_ex = EXT_LAST_EXTENT(eh);
3628 * We should clear the EOFBLOCKS_FL flag if we are writing the
3629 * last block in the last extent in the file. We test this by
3630 * first checking to see if the caller to
3631 * ext4_ext_get_blocks() was interested in the last block (or
3632 * a block beyond the last block) in the current extent. If
3633 * this turns out to be false, we can bail out from this
3634 * function immediately.
3636 if (lblk + len < le32_to_cpu(last_ex->ee_block) +
3637 ext4_ext_get_actual_len(last_ex))
3640 * If the caller does appear to be planning to write at or
3641 * beyond the end of the current extent, we then test to see
3642 * if the current extent is the last extent in the file, by
3643 * checking to make sure it was reached via the rightmost node
3644 * at each level of the tree.
3646 for (i = depth-1; i >= 0; i--)
3647 if (path[i].p_idx != EXT_LAST_INDEX(path[i].p_hdr))
3650 ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
3651 return ext4_mark_inode_dirty(handle, inode);
3655 * ext4_find_delalloc_range: find delayed allocated block in the given range.
3657 * Return 1 if there is a delalloc block in the range, otherwise 0.
3659 int ext4_find_delalloc_range(struct inode *inode,
3660 ext4_lblk_t lblk_start,
3661 ext4_lblk_t lblk_end)
3663 struct extent_status es;
3665 ext4_es_find_delayed_extent_range(inode, lblk_start, lblk_end, &es);
3667 return 0; /* there is no delay extent in this tree */
3668 else if (es.es_lblk <= lblk_start &&
3669 lblk_start < es.es_lblk + es.es_len)
3671 else if (lblk_start <= es.es_lblk && es.es_lblk <= lblk_end)
3677 int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk)
3679 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3680 ext4_lblk_t lblk_start, lblk_end;
3681 lblk_start = lblk & (~(sbi->s_cluster_ratio - 1));
3682 lblk_end = lblk_start + sbi->s_cluster_ratio - 1;
3684 return ext4_find_delalloc_range(inode, lblk_start, lblk_end);
3688 * Determines how many complete clusters (out of those specified by the 'map')
3689 * are under delalloc and were reserved quota for.
3690 * This function is called when we are writing out the blocks that were
3691 * originally written with their allocation delayed, but then the space was
3692 * allocated using fallocate() before the delayed allocation could be resolved.
3693 * The cases to look for are:
3694 * ('=' indicated delayed allocated blocks
3695 * '-' indicates non-delayed allocated blocks)
3696 * (a) partial clusters towards beginning and/or end outside of allocated range
3697 * are not delalloc'ed.
3699 * |----c---=|====c====|====c====|===-c----|
3700 * |++++++ allocated ++++++|
3701 * ==> 4 complete clusters in above example
3703 * (b) partial cluster (outside of allocated range) towards either end is
3704 * marked for delayed allocation. In this case, we will exclude that
3707 * |----====c========|========c========|
3708 * |++++++ allocated ++++++|
3709 * ==> 1 complete clusters in above example
3712 * |================c================|
3713 * |++++++ allocated ++++++|
3714 * ==> 0 complete clusters in above example
3716 * The ext4_da_update_reserve_space will be called only if we
3717 * determine here that there were some "entire" clusters that span
3718 * this 'allocated' range.
3719 * In the non-bigalloc case, this function will just end up returning num_blks
3720 * without ever calling ext4_find_delalloc_range.
3723 get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start,
3724 unsigned int num_blks)
3726 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3727 ext4_lblk_t alloc_cluster_start, alloc_cluster_end;
3728 ext4_lblk_t lblk_from, lblk_to, c_offset;
3729 unsigned int allocated_clusters = 0;
3731 alloc_cluster_start = EXT4_B2C(sbi, lblk_start);
3732 alloc_cluster_end = EXT4_B2C(sbi, lblk_start + num_blks - 1);
3734 /* max possible clusters for this allocation */
3735 allocated_clusters = alloc_cluster_end - alloc_cluster_start + 1;
3737 trace_ext4_get_reserved_cluster_alloc(inode, lblk_start, num_blks);
3739 /* Check towards left side */
3740 c_offset = lblk_start & (sbi->s_cluster_ratio - 1);
3742 lblk_from = lblk_start & (~(sbi->s_cluster_ratio - 1));
3743 lblk_to = lblk_from + c_offset - 1;
3745 if (ext4_find_delalloc_range(inode, lblk_from, lblk_to))
3746 allocated_clusters--;
3749 /* Now check towards right. */
3750 c_offset = (lblk_start + num_blks) & (sbi->s_cluster_ratio - 1);
3751 if (allocated_clusters && c_offset) {
3752 lblk_from = lblk_start + num_blks;
3753 lblk_to = lblk_from + (sbi->s_cluster_ratio - c_offset) - 1;
3755 if (ext4_find_delalloc_range(inode, lblk_from, lblk_to))
3756 allocated_clusters--;
3759 return allocated_clusters;
3763 ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
3764 struct ext4_map_blocks *map,
3765 struct ext4_ext_path *path, int flags,
3766 unsigned int allocated, ext4_fsblk_t newblock)
3770 ext4_io_end_t *io = ext4_inode_aio(inode);
3772 ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical "
3773 "block %llu, max_blocks %u, flags %x, allocated %u\n",
3774 inode->i_ino, (unsigned long long)map->m_lblk, map->m_len,
3776 ext4_ext_show_leaf(inode, path);
3779 * When writing into uninitialized space, we should not fail to
3780 * allocate metadata blocks for the new extent block if needed.
3782 flags |= EXT4_GET_BLOCKS_METADATA_NOFAIL;
3784 trace_ext4_ext_handle_uninitialized_extents(inode, map, flags,
3785 allocated, newblock);
3787 /* get_block() before submit the IO, split the extent */
3788 if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
3789 ret = ext4_split_unwritten_extents(handle, inode, map,
3794 * Flag the inode(non aio case) or end_io struct (aio case)
3795 * that this IO needs to conversion to written when IO is
3799 ext4_set_io_unwritten_flag(inode, io);
3801 ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
3802 map->m_flags |= EXT4_MAP_UNWRITTEN;
3803 if (ext4_should_dioread_nolock(inode))
3804 map->m_flags |= EXT4_MAP_UNINIT;
3807 /* IO end_io complete, convert the filled extent to written */
3808 if ((flags & EXT4_GET_BLOCKS_CONVERT)) {
3809 ret = ext4_convert_unwritten_extents_endio(handle, inode, map,
3812 ext4_update_inode_fsync_trans(handle, inode, 1);
3813 err = check_eofblocks_fl(handle, inode, map->m_lblk,
3817 map->m_flags |= EXT4_MAP_MAPPED;
3818 if (allocated > map->m_len)
3819 allocated = map->m_len;
3820 map->m_len = allocated;
3823 /* buffered IO case */
3825 * repeat fallocate creation request
3826 * we already have an unwritten extent
3828 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT) {
3829 map->m_flags |= EXT4_MAP_UNWRITTEN;
3833 /* buffered READ or buffered write_begin() lookup */
3834 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
3836 * We have blocks reserved already. We
3837 * return allocated blocks so that delalloc
3838 * won't do block reservation for us. But
3839 * the buffer head will be unmapped so that
3840 * a read from the block returns 0s.
3842 map->m_flags |= EXT4_MAP_UNWRITTEN;
3846 /* buffered write, writepage time, convert*/
3847 ret = ext4_ext_convert_to_initialized(handle, inode, map, path, flags);
3849 ext4_update_inode_fsync_trans(handle, inode, 1);
3856 map->m_flags |= EXT4_MAP_NEW;
3858 * if we allocated more blocks than requested
3859 * we need to make sure we unmap the extra block
3860 * allocated. The actual needed block will get
3861 * unmapped later when we find the buffer_head marked
3864 if (allocated > map->m_len) {
3865 unmap_underlying_metadata_blocks(inode->i_sb->s_bdev,
3866 newblock + map->m_len,
3867 allocated - map->m_len);
3868 allocated = map->m_len;
3870 map->m_len = allocated;
3873 * If we have done fallocate with the offset that is already
3874 * delayed allocated, we would have block reservation
3875 * and quota reservation done in the delayed write path.
3876 * But fallocate would have already updated quota and block
3877 * count for this offset. So cancel these reservation
3879 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
3880 unsigned int reserved_clusters;
3881 reserved_clusters = get_reserved_cluster_alloc(inode,
3882 map->m_lblk, map->m_len);
3883 if (reserved_clusters)
3884 ext4_da_update_reserve_space(inode,
3890 map->m_flags |= EXT4_MAP_MAPPED;
3891 if ((flags & EXT4_GET_BLOCKS_KEEP_SIZE) == 0) {
3892 err = check_eofblocks_fl(handle, inode, map->m_lblk, path,
3898 if (allocated > map->m_len)
3899 allocated = map->m_len;
3900 ext4_ext_show_leaf(inode, path);
3901 map->m_pblk = newblock;
3902 map->m_len = allocated;
3905 ext4_ext_drop_refs(path);
3908 return err ? err : allocated;
3912 * get_implied_cluster_alloc - check to see if the requested
3913 * allocation (in the map structure) overlaps with a cluster already
3914 * allocated in an extent.
3915 * @sb The filesystem superblock structure
3916 * @map The requested lblk->pblk mapping
3917 * @ex The extent structure which might contain an implied
3918 * cluster allocation
3920 * This function is called by ext4_ext_map_blocks() after we failed to
3921 * find blocks that were already in the inode's extent tree. Hence,
3922 * we know that the beginning of the requested region cannot overlap
3923 * the extent from the inode's extent tree. There are three cases we
3924 * want to catch. The first is this case:
3926 * |--- cluster # N--|
3927 * |--- extent ---| |---- requested region ---|
3930 * The second case that we need to test for is this one:
3932 * |--------- cluster # N ----------------|
3933 * |--- requested region --| |------- extent ----|
3934 * |=======================|
3936 * The third case is when the requested region lies between two extents
3937 * within the same cluster:
3938 * |------------- cluster # N-------------|
3939 * |----- ex -----| |---- ex_right ----|
3940 * |------ requested region ------|
3941 * |================|
3943 * In each of the above cases, we need to set the map->m_pblk and
3944 * map->m_len so it corresponds to the return the extent labelled as
3945 * "|====|" from cluster #N, since it is already in use for data in
3946 * cluster EXT4_B2C(sbi, map->m_lblk). We will then return 1 to
3947 * signal to ext4_ext_map_blocks() that map->m_pblk should be treated
3948 * as a new "allocated" block region. Otherwise, we will return 0 and
3949 * ext4_ext_map_blocks() will then allocate one or more new clusters
3950 * by calling ext4_mb_new_blocks().
3952 static int get_implied_cluster_alloc(struct super_block *sb,
3953 struct ext4_map_blocks *map,
3954 struct ext4_extent *ex,
3955 struct ext4_ext_path *path)
3957 struct ext4_sb_info *sbi = EXT4_SB(sb);
3958 ext4_lblk_t c_offset = map->m_lblk & (sbi->s_cluster_ratio-1);
3959 ext4_lblk_t ex_cluster_start, ex_cluster_end;
3960 ext4_lblk_t rr_cluster_start;
3961 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
3962 ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
3963 unsigned short ee_len = ext4_ext_get_actual_len(ex);
3965 /* The extent passed in that we are trying to match */
3966 ex_cluster_start = EXT4_B2C(sbi, ee_block);
3967 ex_cluster_end = EXT4_B2C(sbi, ee_block + ee_len - 1);
3969 /* The requested region passed into ext4_map_blocks() */
3970 rr_cluster_start = EXT4_B2C(sbi, map->m_lblk);
3972 if ((rr_cluster_start == ex_cluster_end) ||
3973 (rr_cluster_start == ex_cluster_start)) {
3974 if (rr_cluster_start == ex_cluster_end)
3975 ee_start += ee_len - 1;
3976 map->m_pblk = (ee_start & ~(sbi->s_cluster_ratio - 1)) +
3978 map->m_len = min(map->m_len,
3979 (unsigned) sbi->s_cluster_ratio - c_offset);
3981 * Check for and handle this case:
3983 * |--------- cluster # N-------------|
3984 * |------- extent ----|
3985 * |--- requested region ---|
3989 if (map->m_lblk < ee_block)
3990 map->m_len = min(map->m_len, ee_block - map->m_lblk);
3993 * Check for the case where there is already another allocated
3994 * block to the right of 'ex' but before the end of the cluster.
3996 * |------------- cluster # N-------------|
3997 * |----- ex -----| |---- ex_right ----|
3998 * |------ requested region ------|
3999 * |================|
4001 if (map->m_lblk > ee_block) {
4002 ext4_lblk_t next = ext4_ext_next_allocated_block(path);
4003 map->m_len = min(map->m_len, next - map->m_lblk);
4006 trace_ext4_get_implied_cluster_alloc_exit(sb, map, 1);
4010 trace_ext4_get_implied_cluster_alloc_exit(sb, map, 0);
4016 * Block allocation/map/preallocation routine for extents based files
4019 * Need to be called with
4020 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
4021 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
4023 * return > 0, number of of blocks already mapped/allocated
4024 * if create == 0 and these are pre-allocated blocks
4025 * buffer head is unmapped
4026 * otherwise blocks are mapped
4028 * return = 0, if plain look up failed (blocks have not been allocated)
4029 * buffer head is unmapped
4031 * return < 0, error case.
4033 int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
4034 struct ext4_map_blocks *map, int flags)
4036 struct ext4_ext_path *path = NULL;
4037 struct ext4_extent newex, *ex, *ex2;
4038 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
4039 ext4_fsblk_t newblock = 0;
4040 int free_on_err = 0, err = 0, depth;
4041 unsigned int allocated = 0, offset = 0;
4042 unsigned int allocated_clusters = 0;
4043 struct ext4_allocation_request ar;
4044 ext4_io_end_t *io = ext4_inode_aio(inode);
4045 ext4_lblk_t cluster_offset;
4046 int set_unwritten = 0;
4048 ext_debug("blocks %u/%u requested for inode %lu\n",
4049 map->m_lblk, map->m_len, inode->i_ino);
4050 trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags);
4052 /* find extent for this block */
4053 path = ext4_ext_find_extent(inode, map->m_lblk, NULL);
4055 err = PTR_ERR(path);
4060 depth = ext_depth(inode);
4063 * consistent leaf must not be empty;
4064 * this situation is possible, though, _during_ tree modification;
4065 * this is why assert can't be put in ext4_ext_find_extent()
4067 if (unlikely(path[depth].p_ext == NULL && depth != 0)) {
4068 EXT4_ERROR_INODE(inode, "bad extent address "
4069 "lblock: %lu, depth: %d pblock %lld",
4070 (unsigned long) map->m_lblk, depth,
4071 path[depth].p_block);
4076 ex = path[depth].p_ext;
4078 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
4079 ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
4080 unsigned short ee_len;
4083 * Uninitialized extents are treated as holes, except that
4084 * we split out initialized portions during a write.
4086 ee_len = ext4_ext_get_actual_len(ex);
4088 trace_ext4_ext_show_extent(inode, ee_block, ee_start, ee_len);
4090 /* if found extent covers block, simply return it */
4091 if (in_range(map->m_lblk, ee_block, ee_len)) {
4092 newblock = map->m_lblk - ee_block + ee_start;
4093 /* number of remaining blocks in the extent */
4094 allocated = ee_len - (map->m_lblk - ee_block);
4095 ext_debug("%u fit into %u:%d -> %llu\n", map->m_lblk,
4096 ee_block, ee_len, newblock);
4098 if (!ext4_ext_is_uninitialized(ex))
4101 allocated = ext4_ext_handle_uninitialized_extents(
4102 handle, inode, map, path, flags,
4103 allocated, newblock);
4108 if ((sbi->s_cluster_ratio > 1) &&
4109 ext4_find_delalloc_cluster(inode, map->m_lblk))
4110 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4113 * requested block isn't allocated yet;
4114 * we couldn't try to create block if create flag is zero
4116 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
4118 * put just found gap into cache to speed up
4119 * subsequent requests
4121 if ((flags & EXT4_GET_BLOCKS_NO_PUT_HOLE) == 0)
4122 ext4_ext_put_gap_in_cache(inode, path, map->m_lblk);
4127 * Okay, we need to do block allocation.
4129 map->m_flags &= ~EXT4_MAP_FROM_CLUSTER;
4130 newex.ee_block = cpu_to_le32(map->m_lblk);
4131 cluster_offset = map->m_lblk & (sbi->s_cluster_ratio-1);
4134 * If we are doing bigalloc, check to see if the extent returned
4135 * by ext4_ext_find_extent() implies a cluster we can use.
4137 if (cluster_offset && ex &&
4138 get_implied_cluster_alloc(inode->i_sb, map, ex, path)) {
4139 ar.len = allocated = map->m_len;
4140 newblock = map->m_pblk;
4141 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4142 goto got_allocated_blocks;
4145 /* find neighbour allocated blocks */
4146 ar.lleft = map->m_lblk;
4147 err = ext4_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
4150 ar.lright = map->m_lblk;
4152 err = ext4_ext_search_right(inode, path, &ar.lright, &ar.pright, &ex2);
4156 /* Check if the extent after searching to the right implies a
4157 * cluster we can use. */
4158 if ((sbi->s_cluster_ratio > 1) && ex2 &&
4159 get_implied_cluster_alloc(inode->i_sb, map, ex2, path)) {
4160 ar.len = allocated = map->m_len;
4161 newblock = map->m_pblk;
4162 map->m_flags |= EXT4_MAP_FROM_CLUSTER;
4163 goto got_allocated_blocks;
4167 * See if request is beyond maximum number of blocks we can have in
4168 * a single extent. For an initialized extent this limit is
4169 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
4170 * EXT_UNINIT_MAX_LEN.
4172 if (map->m_len > EXT_INIT_MAX_LEN &&
4173 !(flags & EXT4_GET_BLOCKS_UNINIT_EXT))
4174 map->m_len = EXT_INIT_MAX_LEN;
4175 else if (map->m_len > EXT_UNINIT_MAX_LEN &&
4176 (flags & EXT4_GET_BLOCKS_UNINIT_EXT))
4177 map->m_len = EXT_UNINIT_MAX_LEN;
4179 /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
4180 newex.ee_len = cpu_to_le16(map->m_len);
4181 err = ext4_ext_check_overlap(sbi, inode, &newex, path);
4183 allocated = ext4_ext_get_actual_len(&newex);
4185 allocated = map->m_len;
4187 /* allocate new block */
4189 ar.goal = ext4_ext_find_goal(inode, path, map->m_lblk);
4190 ar.logical = map->m_lblk;
4192 * We calculate the offset from the beginning of the cluster
4193 * for the logical block number, since when we allocate a
4194 * physical cluster, the physical block should start at the
4195 * same offset from the beginning of the cluster. This is
4196 * needed so that future calls to get_implied_cluster_alloc()
4199 offset = map->m_lblk & (sbi->s_cluster_ratio - 1);
4200 ar.len = EXT4_NUM_B2C(sbi, offset+allocated);
4202 ar.logical -= offset;
4203 if (S_ISREG(inode->i_mode))
4204 ar.flags = EXT4_MB_HINT_DATA;
4206 /* disable in-core preallocation for non-regular files */
4208 if (flags & EXT4_GET_BLOCKS_NO_NORMALIZE)
4209 ar.flags |= EXT4_MB_HINT_NOPREALLOC;
4210 newblock = ext4_mb_new_blocks(handle, &ar, &err);
4213 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
4214 ar.goal, newblock, allocated);
4216 allocated_clusters = ar.len;
4217 ar.len = EXT4_C2B(sbi, ar.len) - offset;
4218 if (ar.len > allocated)
4221 got_allocated_blocks:
4222 /* try to insert new extent into found leaf and return */
4223 ext4_ext_store_pblock(&newex, newblock + offset);
4224 newex.ee_len = cpu_to_le16(ar.len);
4225 /* Mark uninitialized */
4226 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){
4227 ext4_ext_mark_uninitialized(&newex);
4228 map->m_flags |= EXT4_MAP_UNWRITTEN;
4230 * io_end structure was created for every IO write to an
4231 * uninitialized extent. To avoid unnecessary conversion,
4232 * here we flag the IO that really needs the conversion.
4233 * For non asycn direct IO case, flag the inode state
4234 * that we need to perform conversion when IO is done.
4236 if ((flags & EXT4_GET_BLOCKS_PRE_IO))
4238 if (ext4_should_dioread_nolock(inode))
4239 map->m_flags |= EXT4_MAP_UNINIT;
4243 if ((flags & EXT4_GET_BLOCKS_KEEP_SIZE) == 0)
4244 err = check_eofblocks_fl(handle, inode, map->m_lblk,
4247 err = ext4_ext_insert_extent(handle, inode, path,
4250 if (!err && set_unwritten) {
4252 ext4_set_io_unwritten_flag(inode, io);
4254 ext4_set_inode_state(inode,
4255 EXT4_STATE_DIO_UNWRITTEN);
4258 if (err && free_on_err) {
4259 int fb_flags = flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE ?
4260 EXT4_FREE_BLOCKS_NO_QUOT_UPDATE : 0;
4261 /* free data blocks we just allocated */
4262 /* not a good idea to call discard here directly,
4263 * but otherwise we'd need to call it every free() */
4264 ext4_discard_preallocations(inode);
4265 ext4_free_blocks(handle, inode, NULL, ext4_ext_pblock(&newex),
4266 ext4_ext_get_actual_len(&newex), fb_flags);
4270 /* previous routine could use block we allocated */
4271 newblock = ext4_ext_pblock(&newex);
4272 allocated = ext4_ext_get_actual_len(&newex);
4273 if (allocated > map->m_len)
4274 allocated = map->m_len;
4275 map->m_flags |= EXT4_MAP_NEW;
4278 * Update reserved blocks/metadata blocks after successful
4279 * block allocation which had been deferred till now.
4281 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
4282 unsigned int reserved_clusters;
4284 * Check how many clusters we had reserved this allocated range
4286 reserved_clusters = get_reserved_cluster_alloc(inode,
4287 map->m_lblk, allocated);
4288 if (map->m_flags & EXT4_MAP_FROM_CLUSTER) {
4289 if (reserved_clusters) {
4291 * We have clusters reserved for this range.
4292 * But since we are not doing actual allocation
4293 * and are simply using blocks from previously
4294 * allocated cluster, we should release the
4295 * reservation and not claim quota.
4297 ext4_da_update_reserve_space(inode,
4298 reserved_clusters, 0);
4301 BUG_ON(allocated_clusters < reserved_clusters);
4302 if (reserved_clusters < allocated_clusters) {
4303 struct ext4_inode_info *ei = EXT4_I(inode);
4304 int reservation = allocated_clusters -
4307 * It seems we claimed few clusters outside of
4308 * the range of this allocation. We should give
4309 * it back to the reservation pool. This can
4310 * happen in the following case:
4312 * * Suppose s_cluster_ratio is 4 (i.e., each
4313 * cluster has 4 blocks. Thus, the clusters
4314 * are [0-3],[4-7],[8-11]...
4315 * * First comes delayed allocation write for
4316 * logical blocks 10 & 11. Since there were no
4317 * previous delayed allocated blocks in the
4318 * range [8-11], we would reserve 1 cluster
4320 * * Next comes write for logical blocks 3 to 8.
4321 * In this case, we will reserve 2 clusters
4322 * (for [0-3] and [4-7]; and not for [8-11] as
4323 * that range has a delayed allocated blocks.
4324 * Thus total reserved clusters now becomes 3.
4325 * * Now, during the delayed allocation writeout
4326 * time, we will first write blocks [3-8] and
4327 * allocate 3 clusters for writing these
4328 * blocks. Also, we would claim all these
4329 * three clusters above.
4330 * * Now when we come here to writeout the
4331 * blocks [10-11], we would expect to claim
4332 * the reservation of 1 cluster we had made
4333 * (and we would claim it since there are no
4334 * more delayed allocated blocks in the range
4335 * [8-11]. But our reserved cluster count had
4336 * already gone to 0.
4338 * Thus, at the step 4 above when we determine
4339 * that there are still some unwritten delayed
4340 * allocated blocks outside of our current
4341 * block range, we should increment the
4342 * reserved clusters count so that when the
4343 * remaining blocks finally gets written, we
4346 dquot_reserve_block(inode,
4347 EXT4_C2B(sbi, reservation));
4348 spin_lock(&ei->i_block_reservation_lock);
4349 ei->i_reserved_data_blocks += reservation;
4350 spin_unlock(&ei->i_block_reservation_lock);
4353 * We will claim quota for all newly allocated blocks.
4354 * We're updating the reserved space *after* the
4355 * correction above so we do not accidentally free
4356 * all the metadata reservation because we might
4357 * actually need it later on.
4359 ext4_da_update_reserve_space(inode, allocated_clusters,
4365 * Cache the extent and update transaction to commit on fdatasync only
4366 * when it is _not_ an uninitialized extent.
4368 if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0)
4369 ext4_update_inode_fsync_trans(handle, inode, 1);
4371 ext4_update_inode_fsync_trans(handle, inode, 0);
4373 if (allocated > map->m_len)
4374 allocated = map->m_len;
4375 ext4_ext_show_leaf(inode, path);
4376 map->m_flags |= EXT4_MAP_MAPPED;
4377 map->m_pblk = newblock;
4378 map->m_len = allocated;
4381 ext4_ext_drop_refs(path);
4386 trace_ext4_ext_map_blocks_exit(inode, map, err ? err : allocated);
4388 return err ? err : allocated;
4391 void ext4_ext_truncate(handle_t *handle, struct inode *inode)
4393 struct super_block *sb = inode->i_sb;
4394 ext4_lblk_t last_block;
4398 * TODO: optimization is possible here.
4399 * Probably we need not scan at all,
4400 * because page truncation is enough.
4403 /* we have to know where to truncate from in crash case */
4404 EXT4_I(inode)->i_disksize = inode->i_size;
4405 ext4_mark_inode_dirty(handle, inode);
4407 last_block = (inode->i_size + sb->s_blocksize - 1)
4408 >> EXT4_BLOCK_SIZE_BITS(sb);
4409 err = ext4_es_remove_extent(inode, last_block,
4410 EXT_MAX_BLOCKS - last_block);
4411 err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
4414 static void ext4_falloc_update_inode(struct inode *inode,
4415 int mode, loff_t new_size, int update_ctime)
4417 struct timespec now;
4420 now = current_fs_time(inode->i_sb);
4421 if (!timespec_equal(&inode->i_ctime, &now))
4422 inode->i_ctime = now;
4425 * Update only when preallocation was requested beyond
4428 if (!(mode & FALLOC_FL_KEEP_SIZE)) {
4429 if (new_size > i_size_read(inode))
4430 i_size_write(inode, new_size);
4431 if (new_size > EXT4_I(inode)->i_disksize)
4432 ext4_update_i_disksize(inode, new_size);
4435 * Mark that we allocate beyond EOF so the subsequent truncate
4436 * can proceed even if the new size is the same as i_size.
4438 if (new_size > i_size_read(inode))
4439 ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
4445 * preallocate space for a file. This implements ext4's fallocate file
4446 * operation, which gets called from sys_fallocate system call.
4447 * For block-mapped files, posix_fallocate should fall back to the method
4448 * of writing zeroes to the required new blocks (the same behavior which is
4449 * expected for file systems which do not support fallocate() system call).
4451 long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
4453 struct inode *inode = file_inode(file);
4456 unsigned int max_blocks;
4461 struct ext4_map_blocks map;
4462 unsigned int credits, blkbits = inode->i_blkbits;
4464 /* Return error if mode is not supported */
4465 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
4468 if (mode & FALLOC_FL_PUNCH_HOLE)
4469 return ext4_punch_hole(file, offset, len);
4471 ret = ext4_convert_inline_data(inode);
4476 * currently supporting (pre)allocate mode for extent-based
4479 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
4482 trace_ext4_fallocate_enter(inode, offset, len, mode);
4483 map.m_lblk = offset >> blkbits;
4485 * We can't just convert len to max_blocks because
4486 * If blocksize = 4096 offset = 3072 and len = 2048
4488 max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
4491 * credits to insert 1 extent into extent tree
4493 credits = ext4_chunk_trans_blocks(inode, max_blocks);
4494 mutex_lock(&inode->i_mutex);
4495 ret = inode_newsize_ok(inode, (len + offset));
4497 mutex_unlock(&inode->i_mutex);
4498 trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
4501 flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT;
4502 if (mode & FALLOC_FL_KEEP_SIZE)
4503 flags |= EXT4_GET_BLOCKS_KEEP_SIZE;
4505 * Don't normalize the request if it can fit in one extent so
4506 * that it doesn't get unnecessarily split into multiple
4509 if (len <= EXT_UNINIT_MAX_LEN << blkbits)
4510 flags |= EXT4_GET_BLOCKS_NO_NORMALIZE;
4513 while (ret >= 0 && ret < max_blocks) {
4514 map.m_lblk = map.m_lblk + ret;
4515 map.m_len = max_blocks = max_blocks - ret;
4516 handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS,
4518 if (IS_ERR(handle)) {
4519 ret = PTR_ERR(handle);
4522 ret = ext4_map_blocks(handle, inode, &map, flags);
4525 ext4_warning(inode->i_sb,
4526 "inode #%lu: block %u: len %u: "
4527 "ext4_ext_map_blocks returned %d",
4528 inode->i_ino, map.m_lblk,
4531 ext4_mark_inode_dirty(handle, inode);
4532 ret2 = ext4_journal_stop(handle);
4535 if ((map.m_lblk + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
4536 blkbits) >> blkbits))
4537 new_size = offset + len;
4539 new_size = ((loff_t) map.m_lblk + ret) << blkbits;
4541 ext4_falloc_update_inode(inode, mode, new_size,
4542 (map.m_flags & EXT4_MAP_NEW));
4543 ext4_mark_inode_dirty(handle, inode);
4544 if ((file->f_flags & O_SYNC) && ret >= max_blocks)
4545 ext4_handle_sync(handle);
4546 ret2 = ext4_journal_stop(handle);
4550 if (ret == -ENOSPC &&
4551 ext4_should_retry_alloc(inode->i_sb, &retries)) {
4555 mutex_unlock(&inode->i_mutex);
4556 trace_ext4_fallocate_exit(inode, offset, max_blocks,
4557 ret > 0 ? ret2 : ret);
4558 return ret > 0 ? ret2 : ret;
4562 * This function convert a range of blocks to written extents
4563 * The caller of this function will pass the start offset and the size.
4564 * all unwritten extents within this range will be converted to
4567 * This function is called from the direct IO end io call back
4568 * function, to convert the fallocated extents after IO is completed.
4569 * Returns 0 on success.
4571 int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
4575 unsigned int max_blocks;
4578 struct ext4_map_blocks map;
4579 unsigned int credits, blkbits = inode->i_blkbits;
4581 map.m_lblk = offset >> blkbits;
4583 * We can't just convert len to max_blocks because
4584 * If blocksize = 4096 offset = 3072 and len = 2048
4586 max_blocks = ((EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) -
4589 * credits to insert 1 extent into extent tree
4591 credits = ext4_chunk_trans_blocks(inode, max_blocks);
4592 while (ret >= 0 && ret < max_blocks) {
4594 map.m_len = (max_blocks -= ret);
4595 handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, credits);
4596 if (IS_ERR(handle)) {
4597 ret = PTR_ERR(handle);
4600 ret = ext4_map_blocks(handle, inode, &map,
4601 EXT4_GET_BLOCKS_IO_CONVERT_EXT);
4603 ext4_warning(inode->i_sb,
4604 "inode #%lu: block %u: len %u: "
4605 "ext4_ext_map_blocks returned %d",
4606 inode->i_ino, map.m_lblk,
4608 ext4_mark_inode_dirty(handle, inode);
4609 ret2 = ext4_journal_stop(handle);
4610 if (ret <= 0 || ret2 )
4613 return ret > 0 ? ret2 : ret;
4617 * If newes is not existing extent (newes->ec_pblk equals zero) find
4618 * delayed extent at start of newes and update newes accordingly and
4619 * return start of the next delayed extent.
4621 * If newes is existing extent (newes->ec_pblk is not equal zero)
4622 * return start of next delayed extent or EXT_MAX_BLOCKS if no delayed
4623 * extent found. Leave newes unmodified.
4625 static int ext4_find_delayed_extent(struct inode *inode,
4626 struct extent_status *newes)
4628 struct extent_status es;
4629 ext4_lblk_t block, next_del;
4631 if (newes->es_pblk == 0) {
4632 ext4_es_find_delayed_extent_range(inode, newes->es_lblk,
4633 newes->es_lblk + newes->es_len - 1, &es);
4636 * No extent in extent-tree contains block @newes->es_pblk,
4637 * then the block may stay in 1)a hole or 2)delayed-extent.
4643 if (es.es_lblk > newes->es_lblk) {
4645 newes->es_len = min(es.es_lblk - newes->es_lblk,
4650 newes->es_len = es.es_lblk + es.es_len - newes->es_lblk;
4653 block = newes->es_lblk + newes->es_len;
4654 ext4_es_find_delayed_extent_range(inode, block, EXT_MAX_BLOCKS, &es);
4656 next_del = EXT_MAX_BLOCKS;
4658 next_del = es.es_lblk;
4662 /* fiemap flags we can handle specified here */
4663 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
4665 static int ext4_xattr_fiemap(struct inode *inode,
4666 struct fiemap_extent_info *fieinfo)
4670 __u32 flags = FIEMAP_EXTENT_LAST;
4671 int blockbits = inode->i_sb->s_blocksize_bits;
4675 if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
4676 struct ext4_iloc iloc;
4677 int offset; /* offset of xattr in inode */
4679 error = ext4_get_inode_loc(inode, &iloc);
4682 physical = (__u64)iloc.bh->b_blocknr << blockbits;
4683 offset = EXT4_GOOD_OLD_INODE_SIZE +
4684 EXT4_I(inode)->i_extra_isize;
4686 length = EXT4_SB(inode->i_sb)->s_inode_size - offset;
4687 flags |= FIEMAP_EXTENT_DATA_INLINE;
4689 } else { /* external block */
4690 physical = (__u64)EXT4_I(inode)->i_file_acl << blockbits;
4691 length = inode->i_sb->s_blocksize;
4695 error = fiemap_fill_next_extent(fieinfo, 0, physical,
4697 return (error < 0 ? error : 0);
4700 int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
4701 __u64 start, __u64 len)
4703 ext4_lblk_t start_blk;
4706 if (ext4_has_inline_data(inode)) {
4709 error = ext4_inline_data_fiemap(inode, fieinfo, &has_inline);
4715 /* fallback to generic here if not in extents fmt */
4716 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
4717 return generic_block_fiemap(inode, fieinfo, start, len,
4720 if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
4723 if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
4724 error = ext4_xattr_fiemap(inode, fieinfo);
4726 ext4_lblk_t len_blks;
4729 start_blk = start >> inode->i_sb->s_blocksize_bits;
4730 last_blk = (start + len - 1) >> inode->i_sb->s_blocksize_bits;
4731 if (last_blk >= EXT_MAX_BLOCKS)
4732 last_blk = EXT_MAX_BLOCKS-1;
4733 len_blks = ((ext4_lblk_t) last_blk) - start_blk + 1;
4736 * Walk the extent tree gathering extent information
4737 * and pushing extents back to the user.
4739 error = ext4_fill_fiemap_extents(inode, start_blk,