2 * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
3 * Written by Alex Tomas <alex@clusterfs.com>
5 * Architecture independence:
6 * Copyright (c) 2005, Bull S.A.
7 * Written by Pierre Peiffer <pierre.peiffer@bull.net>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public Licens
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
24 * Extents support for EXT4
27 * - ext4*_error() should be used in some situations
28 * - analyze all BUG()/BUG_ON(), use -EIO where appropriate
29 * - smart tree reduction
32 #include <linux/module.h>
34 #include <linux/time.h>
35 #include <linux/jbd2.h>
36 #include <linux/highuid.h>
37 #include <linux/pagemap.h>
38 #include <linux/quotaops.h>
39 #include <linux/string.h>
40 #include <linux/slab.h>
41 #include <linux/falloc.h>
42 #include <asm/uaccess.h>
43 #include <linux/fiemap.h>
44 #include "ext4_jbd2.h"
45 #include "ext4_extents.h"
47 #include <trace/events/ext4.h>
49 static int ext4_split_extent(handle_t
*handle
,
51 struct ext4_ext_path
*path
,
52 struct ext4_map_blocks
*map
,
56 static int ext4_ext_truncate_extend_restart(handle_t
*handle
,
62 if (!ext4_handle_valid(handle
))
64 if (handle
->h_buffer_credits
> needed
)
66 err
= ext4_journal_extend(handle
, needed
);
69 err
= ext4_truncate_restart_trans(handle
, inode
, needed
);
81 static int ext4_ext_get_access(handle_t
*handle
, struct inode
*inode
,
82 struct ext4_ext_path
*path
)
85 /* path points to block */
86 return ext4_journal_get_write_access(handle
, path
->p_bh
);
88 /* path points to leaf/index in inode body */
89 /* we use in-core data, no need to protect them */
99 static int ext4_ext_dirty(handle_t
*handle
, struct inode
*inode
,
100 struct ext4_ext_path
*path
)
104 /* path points to block */
105 err
= ext4_handle_dirty_metadata(handle
, inode
, path
->p_bh
);
107 /* path points to leaf/index in inode body */
108 err
= ext4_mark_inode_dirty(handle
, inode
);
113 static ext4_fsblk_t
ext4_ext_find_goal(struct inode
*inode
,
114 struct ext4_ext_path
*path
,
120 struct ext4_extent
*ex
;
121 depth
= path
->p_depth
;
124 * Try to predict block placement assuming that we are
125 * filling in a file which will eventually be
126 * non-sparse --- i.e., in the case of libbfd writing
127 * an ELF object sections out-of-order but in a way
128 * the eventually results in a contiguous object or
129 * executable file, or some database extending a table
130 * space file. However, this is actually somewhat
131 * non-ideal if we are writing a sparse file such as
132 * qemu or KVM writing a raw image file that is going
133 * to stay fairly sparse, since it will end up
134 * fragmenting the file system's free space. Maybe we
135 * should have some hueristics or some way to allow
136 * userspace to pass a hint to file system,
137 * especially if the latter case turns out to be
140 ex
= path
[depth
].p_ext
;
142 ext4_fsblk_t ext_pblk
= ext4_ext_pblock(ex
);
143 ext4_lblk_t ext_block
= le32_to_cpu(ex
->ee_block
);
145 if (block
> ext_block
)
146 return ext_pblk
+ (block
- ext_block
);
148 return ext_pblk
- (ext_block
- block
);
151 /* it looks like index is empty;
152 * try to find starting block from index itself */
153 if (path
[depth
].p_bh
)
154 return path
[depth
].p_bh
->b_blocknr
;
157 /* OK. use inode's group */
158 return ext4_inode_to_goal_block(inode
);
162 * Allocation for a meta data block
165 ext4_ext_new_meta_block(handle_t
*handle
, struct inode
*inode
,
166 struct ext4_ext_path
*path
,
167 struct ext4_extent
*ex
, int *err
, unsigned int flags
)
169 ext4_fsblk_t goal
, newblock
;
171 goal
= ext4_ext_find_goal(inode
, path
, le32_to_cpu(ex
->ee_block
));
172 newblock
= ext4_new_meta_blocks(handle
, inode
, goal
, flags
,
177 static inline int ext4_ext_space_block(struct inode
*inode
, int check
)
181 size
= (inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
182 / sizeof(struct ext4_extent
);
184 #ifdef AGGRESSIVE_TEST
192 static inline int ext4_ext_space_block_idx(struct inode
*inode
, int check
)
196 size
= (inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
197 / sizeof(struct ext4_extent_idx
);
199 #ifdef AGGRESSIVE_TEST
207 static inline int ext4_ext_space_root(struct inode
*inode
, int check
)
211 size
= sizeof(EXT4_I(inode
)->i_data
);
212 size
-= sizeof(struct ext4_extent_header
);
213 size
/= sizeof(struct ext4_extent
);
215 #ifdef AGGRESSIVE_TEST
223 static inline int ext4_ext_space_root_idx(struct inode
*inode
, int check
)
227 size
= sizeof(EXT4_I(inode
)->i_data
);
228 size
-= sizeof(struct ext4_extent_header
);
229 size
/= sizeof(struct ext4_extent_idx
);
231 #ifdef AGGRESSIVE_TEST
240 * Calculate the number of metadata blocks needed
241 * to allocate @blocks
242 * Worse case is one block per extent
244 int ext4_ext_calc_metadata_amount(struct inode
*inode
, ext4_lblk_t lblock
)
246 struct ext4_inode_info
*ei
= EXT4_I(inode
);
249 idxs
= ((inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
250 / sizeof(struct ext4_extent_idx
));
253 * If the new delayed allocation block is contiguous with the
254 * previous da block, it can share index blocks with the
255 * previous block, so we only need to allocate a new index
256 * block every idxs leaf blocks. At ldxs**2 blocks, we need
257 * an additional index block, and at ldxs**3 blocks, yet
258 * another index blocks.
260 if (ei
->i_da_metadata_calc_len
&&
261 ei
->i_da_metadata_calc_last_lblock
+1 == lblock
) {
262 if ((ei
->i_da_metadata_calc_len
% idxs
) == 0)
264 if ((ei
->i_da_metadata_calc_len
% (idxs
*idxs
)) == 0)
266 if ((ei
->i_da_metadata_calc_len
% (idxs
*idxs
*idxs
)) == 0) {
268 ei
->i_da_metadata_calc_len
= 0;
270 ei
->i_da_metadata_calc_len
++;
271 ei
->i_da_metadata_calc_last_lblock
++;
276 * In the worst case we need a new set of index blocks at
277 * every level of the inode's extent tree.
279 ei
->i_da_metadata_calc_len
= 1;
280 ei
->i_da_metadata_calc_last_lblock
= lblock
;
281 return ext_depth(inode
) + 1;
285 ext4_ext_max_entries(struct inode
*inode
, int depth
)
289 if (depth
== ext_depth(inode
)) {
291 max
= ext4_ext_space_root(inode
, 1);
293 max
= ext4_ext_space_root_idx(inode
, 1);
296 max
= ext4_ext_space_block(inode
, 1);
298 max
= ext4_ext_space_block_idx(inode
, 1);
304 static int ext4_valid_extent(struct inode
*inode
, struct ext4_extent
*ext
)
306 ext4_fsblk_t block
= ext4_ext_pblock(ext
);
307 int len
= ext4_ext_get_actual_len(ext
);
309 return ext4_data_block_valid(EXT4_SB(inode
->i_sb
), block
, len
);
312 static int ext4_valid_extent_idx(struct inode
*inode
,
313 struct ext4_extent_idx
*ext_idx
)
315 ext4_fsblk_t block
= ext4_idx_pblock(ext_idx
);
317 return ext4_data_block_valid(EXT4_SB(inode
->i_sb
), block
, 1);
320 static int ext4_valid_extent_entries(struct inode
*inode
,
321 struct ext4_extent_header
*eh
,
324 struct ext4_extent
*ext
;
325 struct ext4_extent_idx
*ext_idx
;
326 unsigned short entries
;
327 if (eh
->eh_entries
== 0)
330 entries
= le16_to_cpu(eh
->eh_entries
);
334 ext
= EXT_FIRST_EXTENT(eh
);
336 if (!ext4_valid_extent(inode
, ext
))
342 ext_idx
= EXT_FIRST_INDEX(eh
);
344 if (!ext4_valid_extent_idx(inode
, ext_idx
))
353 static int __ext4_ext_check(const char *function
, unsigned int line
,
354 struct inode
*inode
, struct ext4_extent_header
*eh
,
357 const char *error_msg
;
360 if (unlikely(eh
->eh_magic
!= EXT4_EXT_MAGIC
)) {
361 error_msg
= "invalid magic";
364 if (unlikely(le16_to_cpu(eh
->eh_depth
) != depth
)) {
365 error_msg
= "unexpected eh_depth";
368 if (unlikely(eh
->eh_max
== 0)) {
369 error_msg
= "invalid eh_max";
372 max
= ext4_ext_max_entries(inode
, depth
);
373 if (unlikely(le16_to_cpu(eh
->eh_max
) > max
)) {
374 error_msg
= "too large eh_max";
377 if (unlikely(le16_to_cpu(eh
->eh_entries
) > le16_to_cpu(eh
->eh_max
))) {
378 error_msg
= "invalid eh_entries";
381 if (!ext4_valid_extent_entries(inode
, eh
, depth
)) {
382 error_msg
= "invalid extent entries";
388 ext4_error_inode(inode
, function
, line
, 0,
389 "bad header/extent: %s - magic %x, "
390 "entries %u, max %u(%u), depth %u(%u)",
391 error_msg
, le16_to_cpu(eh
->eh_magic
),
392 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
),
393 max
, le16_to_cpu(eh
->eh_depth
), depth
);
398 #define ext4_ext_check(inode, eh, depth) \
399 __ext4_ext_check(__func__, __LINE__, inode, eh, depth)
401 int ext4_ext_check_inode(struct inode
*inode
)
403 return ext4_ext_check(inode
, ext_inode_hdr(inode
), ext_depth(inode
));
407 static void ext4_ext_show_path(struct inode
*inode
, struct ext4_ext_path
*path
)
409 int k
, l
= path
->p_depth
;
412 for (k
= 0; k
<= l
; k
++, path
++) {
414 ext_debug(" %d->%llu", le32_to_cpu(path
->p_idx
->ei_block
),
415 ext4_idx_pblock(path
->p_idx
));
416 } else if (path
->p_ext
) {
417 ext_debug(" %d:[%d]%d:%llu ",
418 le32_to_cpu(path
->p_ext
->ee_block
),
419 ext4_ext_is_uninitialized(path
->p_ext
),
420 ext4_ext_get_actual_len(path
->p_ext
),
421 ext4_ext_pblock(path
->p_ext
));
428 static void ext4_ext_show_leaf(struct inode
*inode
, struct ext4_ext_path
*path
)
430 int depth
= ext_depth(inode
);
431 struct ext4_extent_header
*eh
;
432 struct ext4_extent
*ex
;
438 eh
= path
[depth
].p_hdr
;
439 ex
= EXT_FIRST_EXTENT(eh
);
441 ext_debug("Displaying leaf extents for inode %lu\n", inode
->i_ino
);
443 for (i
= 0; i
< le16_to_cpu(eh
->eh_entries
); i
++, ex
++) {
444 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex
->ee_block
),
445 ext4_ext_is_uninitialized(ex
),
446 ext4_ext_get_actual_len(ex
), ext4_ext_pblock(ex
));
451 static void ext4_ext_show_move(struct inode
*inode
, struct ext4_ext_path
*path
,
452 ext4_fsblk_t newblock
, int level
)
454 int depth
= ext_depth(inode
);
455 struct ext4_extent
*ex
;
457 if (depth
!= level
) {
458 struct ext4_extent_idx
*idx
;
459 idx
= path
[level
].p_idx
;
460 while (idx
<= EXT_MAX_INDEX(path
[level
].p_hdr
)) {
461 ext_debug("%d: move %d:%llu in new index %llu\n", level
,
462 le32_to_cpu(idx
->ei_block
),
463 ext4_idx_pblock(idx
),
471 ex
= path
[depth
].p_ext
;
472 while (ex
<= EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
473 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
474 le32_to_cpu(ex
->ee_block
),
476 ext4_ext_is_uninitialized(ex
),
477 ext4_ext_get_actual_len(ex
),
484 #define ext4_ext_show_path(inode, path)
485 #define ext4_ext_show_leaf(inode, path)
486 #define ext4_ext_show_move(inode, path, newblock, level)
489 void ext4_ext_drop_refs(struct ext4_ext_path
*path
)
491 int depth
= path
->p_depth
;
494 for (i
= 0; i
<= depth
; i
++, path
++)
502 * ext4_ext_binsearch_idx:
503 * binary search for the closest index of the given block
504 * the header must be checked before calling this
507 ext4_ext_binsearch_idx(struct inode
*inode
,
508 struct ext4_ext_path
*path
, ext4_lblk_t block
)
510 struct ext4_extent_header
*eh
= path
->p_hdr
;
511 struct ext4_extent_idx
*r
, *l
, *m
;
514 ext_debug("binsearch for %u(idx): ", block
);
516 l
= EXT_FIRST_INDEX(eh
) + 1;
517 r
= EXT_LAST_INDEX(eh
);
520 if (block
< le32_to_cpu(m
->ei_block
))
524 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ei_block
),
525 m
, le32_to_cpu(m
->ei_block
),
526 r
, le32_to_cpu(r
->ei_block
));
530 ext_debug(" -> %d->%lld ", le32_to_cpu(path
->p_idx
->ei_block
),
531 ext4_idx_pblock(path
->p_idx
));
533 #ifdef CHECK_BINSEARCH
535 struct ext4_extent_idx
*chix
, *ix
;
538 chix
= ix
= EXT_FIRST_INDEX(eh
);
539 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ix
++) {
541 le32_to_cpu(ix
->ei_block
) <= le32_to_cpu(ix
[-1].ei_block
)) {
542 printk(KERN_DEBUG
"k=%d, ix=0x%p, "
544 ix
, EXT_FIRST_INDEX(eh
));
545 printk(KERN_DEBUG
"%u <= %u\n",
546 le32_to_cpu(ix
->ei_block
),
547 le32_to_cpu(ix
[-1].ei_block
));
549 BUG_ON(k
&& le32_to_cpu(ix
->ei_block
)
550 <= le32_to_cpu(ix
[-1].ei_block
));
551 if (block
< le32_to_cpu(ix
->ei_block
))
555 BUG_ON(chix
!= path
->p_idx
);
562 * ext4_ext_binsearch:
563 * binary search for closest extent of the given block
564 * the header must be checked before calling this
567 ext4_ext_binsearch(struct inode
*inode
,
568 struct ext4_ext_path
*path
, ext4_lblk_t block
)
570 struct ext4_extent_header
*eh
= path
->p_hdr
;
571 struct ext4_extent
*r
, *l
, *m
;
573 if (eh
->eh_entries
== 0) {
575 * this leaf is empty:
576 * we get such a leaf in split/add case
581 ext_debug("binsearch for %u: ", block
);
583 l
= EXT_FIRST_EXTENT(eh
) + 1;
584 r
= EXT_LAST_EXTENT(eh
);
588 if (block
< le32_to_cpu(m
->ee_block
))
592 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ee_block
),
593 m
, le32_to_cpu(m
->ee_block
),
594 r
, le32_to_cpu(r
->ee_block
));
598 ext_debug(" -> %d:%llu:[%d]%d ",
599 le32_to_cpu(path
->p_ext
->ee_block
),
600 ext4_ext_pblock(path
->p_ext
),
601 ext4_ext_is_uninitialized(path
->p_ext
),
602 ext4_ext_get_actual_len(path
->p_ext
));
604 #ifdef CHECK_BINSEARCH
606 struct ext4_extent
*chex
, *ex
;
609 chex
= ex
= EXT_FIRST_EXTENT(eh
);
610 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ex
++) {
611 BUG_ON(k
&& le32_to_cpu(ex
->ee_block
)
612 <= le32_to_cpu(ex
[-1].ee_block
));
613 if (block
< le32_to_cpu(ex
->ee_block
))
617 BUG_ON(chex
!= path
->p_ext
);
623 int ext4_ext_tree_init(handle_t
*handle
, struct inode
*inode
)
625 struct ext4_extent_header
*eh
;
627 eh
= ext_inode_hdr(inode
);
630 eh
->eh_magic
= EXT4_EXT_MAGIC
;
631 eh
->eh_max
= cpu_to_le16(ext4_ext_space_root(inode
, 0));
632 ext4_mark_inode_dirty(handle
, inode
);
633 ext4_ext_invalidate_cache(inode
);
637 struct ext4_ext_path
*
638 ext4_ext_find_extent(struct inode
*inode
, ext4_lblk_t block
,
639 struct ext4_ext_path
*path
)
641 struct ext4_extent_header
*eh
;
642 struct buffer_head
*bh
;
643 short int depth
, i
, ppos
= 0, alloc
= 0;
645 eh
= ext_inode_hdr(inode
);
646 depth
= ext_depth(inode
);
648 /* account possible depth increase */
650 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 2),
653 return ERR_PTR(-ENOMEM
);
660 /* walk through the tree */
662 int need_to_validate
= 0;
664 ext_debug("depth %d: num %d, max %d\n",
665 ppos
, le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
667 ext4_ext_binsearch_idx(inode
, path
+ ppos
, block
);
668 path
[ppos
].p_block
= ext4_idx_pblock(path
[ppos
].p_idx
);
669 path
[ppos
].p_depth
= i
;
670 path
[ppos
].p_ext
= NULL
;
672 bh
= sb_getblk(inode
->i_sb
, path
[ppos
].p_block
);
675 if (!bh_uptodate_or_lock(bh
)) {
676 trace_ext4_ext_load_extent(inode
, block
,
678 if (bh_submit_read(bh
) < 0) {
682 /* validate the extent entries */
683 need_to_validate
= 1;
685 eh
= ext_block_hdr(bh
);
687 if (unlikely(ppos
> depth
)) {
689 EXT4_ERROR_INODE(inode
,
690 "ppos %d > depth %d", ppos
, depth
);
693 path
[ppos
].p_bh
= bh
;
694 path
[ppos
].p_hdr
= eh
;
697 if (need_to_validate
&& ext4_ext_check(inode
, eh
, i
))
701 path
[ppos
].p_depth
= i
;
702 path
[ppos
].p_ext
= NULL
;
703 path
[ppos
].p_idx
= NULL
;
706 ext4_ext_binsearch(inode
, path
+ ppos
, block
);
707 /* if not an empty leaf */
708 if (path
[ppos
].p_ext
)
709 path
[ppos
].p_block
= ext4_ext_pblock(path
[ppos
].p_ext
);
711 ext4_ext_show_path(inode
, path
);
716 ext4_ext_drop_refs(path
);
719 return ERR_PTR(-EIO
);
723 * ext4_ext_insert_index:
724 * insert new index [@logical;@ptr] into the block at @curp;
725 * check where to insert: before @curp or after @curp
727 static int ext4_ext_insert_index(handle_t
*handle
, struct inode
*inode
,
728 struct ext4_ext_path
*curp
,
729 int logical
, ext4_fsblk_t ptr
)
731 struct ext4_extent_idx
*ix
;
734 err
= ext4_ext_get_access(handle
, inode
, curp
);
738 if (unlikely(logical
== le32_to_cpu(curp
->p_idx
->ei_block
))) {
739 EXT4_ERROR_INODE(inode
,
740 "logical %d == ei_block %d!",
741 logical
, le32_to_cpu(curp
->p_idx
->ei_block
));
745 if (unlikely(le16_to_cpu(curp
->p_hdr
->eh_entries
)
746 >= le16_to_cpu(curp
->p_hdr
->eh_max
))) {
747 EXT4_ERROR_INODE(inode
,
748 "eh_entries %d >= eh_max %d!",
749 le16_to_cpu(curp
->p_hdr
->eh_entries
),
750 le16_to_cpu(curp
->p_hdr
->eh_max
));
754 len
= EXT_MAX_INDEX(curp
->p_hdr
) - curp
->p_idx
;
755 if (logical
> le32_to_cpu(curp
->p_idx
->ei_block
)) {
757 if (curp
->p_idx
!= EXT_LAST_INDEX(curp
->p_hdr
)) {
758 len
= (len
- 1) * sizeof(struct ext4_extent_idx
);
759 len
= len
< 0 ? 0 : len
;
760 ext_debug("insert new index %d after: %llu. "
761 "move %d from 0x%p to 0x%p\n",
763 (curp
->p_idx
+ 1), (curp
->p_idx
+ 2));
764 memmove(curp
->p_idx
+ 2, curp
->p_idx
+ 1, len
);
766 ix
= curp
->p_idx
+ 1;
769 len
= len
* sizeof(struct ext4_extent_idx
);
770 len
= len
< 0 ? 0 : len
;
771 ext_debug("insert new index %d before: %llu. "
772 "move %d from 0x%p to 0x%p\n",
774 curp
->p_idx
, (curp
->p_idx
+ 1));
775 memmove(curp
->p_idx
+ 1, curp
->p_idx
, len
);
779 ix
->ei_block
= cpu_to_le32(logical
);
780 ext4_idx_store_pblock(ix
, ptr
);
781 le16_add_cpu(&curp
->p_hdr
->eh_entries
, 1);
783 if (unlikely(ix
> EXT_LAST_INDEX(curp
->p_hdr
))) {
784 EXT4_ERROR_INODE(inode
, "ix > EXT_LAST_INDEX!");
788 err
= ext4_ext_dirty(handle
, inode
, curp
);
789 ext4_std_error(inode
->i_sb
, err
);
796 * inserts new subtree into the path, using free index entry
798 * - allocates all needed blocks (new leaf and all intermediate index blocks)
799 * - makes decision where to split
800 * - moves remaining extents and index entries (right to the split point)
801 * into the newly allocated blocks
802 * - initializes subtree
804 static int ext4_ext_split(handle_t
*handle
, struct inode
*inode
,
806 struct ext4_ext_path
*path
,
807 struct ext4_extent
*newext
, int at
)
809 struct buffer_head
*bh
= NULL
;
810 int depth
= ext_depth(inode
);
811 struct ext4_extent_header
*neh
;
812 struct ext4_extent_idx
*fidx
;
814 ext4_fsblk_t newblock
, oldblock
;
816 ext4_fsblk_t
*ablocks
= NULL
; /* array of allocated blocks */
819 /* make decision: where to split? */
820 /* FIXME: now decision is simplest: at current extent */
822 /* if current leaf will be split, then we should use
823 * border from split point */
824 if (unlikely(path
[depth
].p_ext
> EXT_MAX_EXTENT(path
[depth
].p_hdr
))) {
825 EXT4_ERROR_INODE(inode
, "p_ext > EXT_MAX_EXTENT!");
828 if (path
[depth
].p_ext
!= EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
829 border
= path
[depth
].p_ext
[1].ee_block
;
830 ext_debug("leaf will be split."
831 " next leaf starts at %d\n",
832 le32_to_cpu(border
));
834 border
= newext
->ee_block
;
835 ext_debug("leaf will be added."
836 " next leaf starts at %d\n",
837 le32_to_cpu(border
));
841 * If error occurs, then we break processing
842 * and mark filesystem read-only. index won't
843 * be inserted and tree will be in consistent
844 * state. Next mount will repair buffers too.
848 * Get array to track all allocated blocks.
849 * We need this to handle errors and free blocks
852 ablocks
= kzalloc(sizeof(ext4_fsblk_t
) * depth
, GFP_NOFS
);
856 /* allocate all needed blocks */
857 ext_debug("allocate %d blocks for indexes/leaf\n", depth
- at
);
858 for (a
= 0; a
< depth
- at
; a
++) {
859 newblock
= ext4_ext_new_meta_block(handle
, inode
, path
,
860 newext
, &err
, flags
);
863 ablocks
[a
] = newblock
;
866 /* initialize new leaf */
867 newblock
= ablocks
[--a
];
868 if (unlikely(newblock
== 0)) {
869 EXT4_ERROR_INODE(inode
, "newblock == 0!");
873 bh
= sb_getblk(inode
->i_sb
, newblock
);
880 err
= ext4_journal_get_create_access(handle
, bh
);
884 neh
= ext_block_hdr(bh
);
886 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
, 0));
887 neh
->eh_magic
= EXT4_EXT_MAGIC
;
890 /* move remainder of path[depth] to the new leaf */
891 if (unlikely(path
[depth
].p_hdr
->eh_entries
!=
892 path
[depth
].p_hdr
->eh_max
)) {
893 EXT4_ERROR_INODE(inode
, "eh_entries %d != eh_max %d!",
894 path
[depth
].p_hdr
->eh_entries
,
895 path
[depth
].p_hdr
->eh_max
);
899 /* start copy from next extent */
900 m
= EXT_MAX_EXTENT(path
[depth
].p_hdr
) - path
[depth
].p_ext
++;
901 ext4_ext_show_move(inode
, path
, newblock
, depth
);
903 struct ext4_extent
*ex
;
904 ex
= EXT_FIRST_EXTENT(neh
);
905 memmove(ex
, path
[depth
].p_ext
, sizeof(struct ext4_extent
) * m
);
906 le16_add_cpu(&neh
->eh_entries
, m
);
909 set_buffer_uptodate(bh
);
912 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
918 /* correct old leaf */
920 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
923 le16_add_cpu(&path
[depth
].p_hdr
->eh_entries
, -m
);
924 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
930 /* create intermediate indexes */
932 if (unlikely(k
< 0)) {
933 EXT4_ERROR_INODE(inode
, "k %d < 0!", k
);
938 ext_debug("create %d intermediate indices\n", k
);
939 /* insert new index into current index block */
940 /* current depth stored in i var */
944 newblock
= ablocks
[--a
];
945 bh
= sb_getblk(inode
->i_sb
, newblock
);
952 err
= ext4_journal_get_create_access(handle
, bh
);
956 neh
= ext_block_hdr(bh
);
957 neh
->eh_entries
= cpu_to_le16(1);
958 neh
->eh_magic
= EXT4_EXT_MAGIC
;
959 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
, 0));
960 neh
->eh_depth
= cpu_to_le16(depth
- i
);
961 fidx
= EXT_FIRST_INDEX(neh
);
962 fidx
->ei_block
= border
;
963 ext4_idx_store_pblock(fidx
, oldblock
);
965 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
966 i
, newblock
, le32_to_cpu(border
), oldblock
);
968 /* move remainder of path[i] to the new index block */
969 if (unlikely(EXT_MAX_INDEX(path
[i
].p_hdr
) !=
970 EXT_LAST_INDEX(path
[i
].p_hdr
))) {
971 EXT4_ERROR_INODE(inode
,
972 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
973 le32_to_cpu(path
[i
].p_ext
->ee_block
));
977 /* start copy indexes */
978 m
= EXT_MAX_INDEX(path
[i
].p_hdr
) - path
[i
].p_idx
++;
979 ext_debug("cur 0x%p, last 0x%p\n", path
[i
].p_idx
,
980 EXT_MAX_INDEX(path
[i
].p_hdr
));
981 ext4_ext_show_move(inode
, path
, newblock
, i
);
983 memmove(++fidx
, path
[i
].p_idx
,
984 sizeof(struct ext4_extent_idx
) * m
);
985 le16_add_cpu(&neh
->eh_entries
, m
);
987 set_buffer_uptodate(bh
);
990 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
996 /* correct old index */
998 err
= ext4_ext_get_access(handle
, inode
, path
+ i
);
1001 le16_add_cpu(&path
[i
].p_hdr
->eh_entries
, -m
);
1002 err
= ext4_ext_dirty(handle
, inode
, path
+ i
);
1010 /* insert new index */
1011 err
= ext4_ext_insert_index(handle
, inode
, path
+ at
,
1012 le32_to_cpu(border
), newblock
);
1016 if (buffer_locked(bh
))
1022 /* free all allocated blocks in error case */
1023 for (i
= 0; i
< depth
; i
++) {
1026 ext4_free_blocks(handle
, inode
, NULL
, ablocks
[i
], 1,
1027 EXT4_FREE_BLOCKS_METADATA
);
1036 * ext4_ext_grow_indepth:
1037 * implements tree growing procedure:
1038 * - allocates new block
1039 * - moves top-level data (index block or leaf) into the new block
1040 * - initializes new top-level, creating index that points to the
1041 * just created block
1043 static int ext4_ext_grow_indepth(handle_t
*handle
, struct inode
*inode
,
1045 struct ext4_ext_path
*path
,
1046 struct ext4_extent
*newext
)
1048 struct ext4_ext_path
*curp
= path
;
1049 struct ext4_extent_header
*neh
;
1050 struct buffer_head
*bh
;
1051 ext4_fsblk_t newblock
;
1054 newblock
= ext4_ext_new_meta_block(handle
, inode
, path
,
1055 newext
, &err
, flags
);
1059 bh
= sb_getblk(inode
->i_sb
, newblock
);
1062 ext4_std_error(inode
->i_sb
, err
);
1067 err
= ext4_journal_get_create_access(handle
, bh
);
1073 /* move top-level index/leaf into new block */
1074 memmove(bh
->b_data
, curp
->p_hdr
, sizeof(EXT4_I(inode
)->i_data
));
1076 /* set size of new block */
1077 neh
= ext_block_hdr(bh
);
1078 /* old root could have indexes or leaves
1079 * so calculate e_max right way */
1080 if (ext_depth(inode
))
1081 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
, 0));
1083 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
, 0));
1084 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1085 set_buffer_uptodate(bh
);
1088 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1092 /* create index in new top-level index: num,max,pointer */
1093 err
= ext4_ext_get_access(handle
, inode
, curp
);
1097 curp
->p_hdr
->eh_magic
= EXT4_EXT_MAGIC
;
1098 curp
->p_hdr
->eh_max
= cpu_to_le16(ext4_ext_space_root_idx(inode
, 0));
1099 curp
->p_hdr
->eh_entries
= cpu_to_le16(1);
1100 curp
->p_idx
= EXT_FIRST_INDEX(curp
->p_hdr
);
1102 if (path
[0].p_hdr
->eh_depth
)
1103 curp
->p_idx
->ei_block
=
1104 EXT_FIRST_INDEX(path
[0].p_hdr
)->ei_block
;
1106 curp
->p_idx
->ei_block
=
1107 EXT_FIRST_EXTENT(path
[0].p_hdr
)->ee_block
;
1108 ext4_idx_store_pblock(curp
->p_idx
, newblock
);
1110 neh
= ext_inode_hdr(inode
);
1111 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1112 le16_to_cpu(neh
->eh_entries
), le16_to_cpu(neh
->eh_max
),
1113 le32_to_cpu(EXT_FIRST_INDEX(neh
)->ei_block
),
1114 ext4_idx_pblock(EXT_FIRST_INDEX(neh
)));
1116 neh
->eh_depth
= cpu_to_le16(path
->p_depth
+ 1);
1117 err
= ext4_ext_dirty(handle
, inode
, curp
);
1125 * ext4_ext_create_new_leaf:
1126 * finds empty index and adds new leaf.
1127 * if no free index is found, then it requests in-depth growing.
1129 static int ext4_ext_create_new_leaf(handle_t
*handle
, struct inode
*inode
,
1131 struct ext4_ext_path
*path
,
1132 struct ext4_extent
*newext
)
1134 struct ext4_ext_path
*curp
;
1135 int depth
, i
, err
= 0;
1138 i
= depth
= ext_depth(inode
);
1140 /* walk up to the tree and look for free index entry */
1141 curp
= path
+ depth
;
1142 while (i
> 0 && !EXT_HAS_FREE_INDEX(curp
)) {
1147 /* we use already allocated block for index block,
1148 * so subsequent data blocks should be contiguous */
1149 if (EXT_HAS_FREE_INDEX(curp
)) {
1150 /* if we found index with free entry, then use that
1151 * entry: create all needed subtree and add new leaf */
1152 err
= ext4_ext_split(handle
, inode
, flags
, path
, newext
, i
);
1157 ext4_ext_drop_refs(path
);
1158 path
= ext4_ext_find_extent(inode
,
1159 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1162 err
= PTR_ERR(path
);
1164 /* tree is full, time to grow in depth */
1165 err
= ext4_ext_grow_indepth(handle
, inode
, flags
,
1171 ext4_ext_drop_refs(path
);
1172 path
= ext4_ext_find_extent(inode
,
1173 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1176 err
= PTR_ERR(path
);
1181 * only first (depth 0 -> 1) produces free space;
1182 * in all other cases we have to split the grown tree
1184 depth
= ext_depth(inode
);
1185 if (path
[depth
].p_hdr
->eh_entries
== path
[depth
].p_hdr
->eh_max
) {
1186 /* now we need to split */
1196 * search the closest allocated block to the left for *logical
1197 * and returns it at @logical + it's physical address at @phys
1198 * if *logical is the smallest allocated block, the function
1199 * returns 0 at @phys
1200 * return value contains 0 (success) or error code
1202 static int ext4_ext_search_left(struct inode
*inode
,
1203 struct ext4_ext_path
*path
,
1204 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
)
1206 struct ext4_extent_idx
*ix
;
1207 struct ext4_extent
*ex
;
1210 if (unlikely(path
== NULL
)) {
1211 EXT4_ERROR_INODE(inode
, "path == NULL *logical %d!", *logical
);
1214 depth
= path
->p_depth
;
1217 if (depth
== 0 && path
->p_ext
== NULL
)
1220 /* usually extent in the path covers blocks smaller
1221 * then *logical, but it can be that extent is the
1222 * first one in the file */
1224 ex
= path
[depth
].p_ext
;
1225 ee_len
= ext4_ext_get_actual_len(ex
);
1226 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1227 if (unlikely(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
)) {
1228 EXT4_ERROR_INODE(inode
,
1229 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
1230 *logical
, le32_to_cpu(ex
->ee_block
));
1233 while (--depth
>= 0) {
1234 ix
= path
[depth
].p_idx
;
1235 if (unlikely(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
))) {
1236 EXT4_ERROR_INODE(inode
,
1237 "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
1238 ix
!= NULL
? ix
->ei_block
: 0,
1239 EXT_FIRST_INDEX(path
[depth
].p_hdr
) != NULL
?
1240 EXT_FIRST_INDEX(path
[depth
].p_hdr
)->ei_block
: 0,
1248 if (unlikely(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
))) {
1249 EXT4_ERROR_INODE(inode
,
1250 "logical %d < ee_block %d + ee_len %d!",
1251 *logical
, le32_to_cpu(ex
->ee_block
), ee_len
);
1255 *logical
= le32_to_cpu(ex
->ee_block
) + ee_len
- 1;
1256 *phys
= ext4_ext_pblock(ex
) + ee_len
- 1;
1261 * search the closest allocated block to the right for *logical
1262 * and returns it at @logical + it's physical address at @phys
1263 * if *logical is the smallest allocated block, the function
1264 * returns 0 at @phys
1265 * return value contains 0 (success) or error code
1267 static int ext4_ext_search_right(struct inode
*inode
,
1268 struct ext4_ext_path
*path
,
1269 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
)
1271 struct buffer_head
*bh
= NULL
;
1272 struct ext4_extent_header
*eh
;
1273 struct ext4_extent_idx
*ix
;
1274 struct ext4_extent
*ex
;
1276 int depth
; /* Note, NOT eh_depth; depth from top of tree */
1279 if (unlikely(path
== NULL
)) {
1280 EXT4_ERROR_INODE(inode
, "path == NULL *logical %d!", *logical
);
1283 depth
= path
->p_depth
;
1286 if (depth
== 0 && path
->p_ext
== NULL
)
1289 /* usually extent in the path covers blocks smaller
1290 * then *logical, but it can be that extent is the
1291 * first one in the file */
1293 ex
= path
[depth
].p_ext
;
1294 ee_len
= ext4_ext_get_actual_len(ex
);
1295 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1296 if (unlikely(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
)) {
1297 EXT4_ERROR_INODE(inode
,
1298 "first_extent(path[%d].p_hdr) != ex",
1302 while (--depth
>= 0) {
1303 ix
= path
[depth
].p_idx
;
1304 if (unlikely(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
))) {
1305 EXT4_ERROR_INODE(inode
,
1306 "ix != EXT_FIRST_INDEX *logical %d!",
1311 *logical
= le32_to_cpu(ex
->ee_block
);
1312 *phys
= ext4_ext_pblock(ex
);
1316 if (unlikely(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
))) {
1317 EXT4_ERROR_INODE(inode
,
1318 "logical %d < ee_block %d + ee_len %d!",
1319 *logical
, le32_to_cpu(ex
->ee_block
), ee_len
);
1323 if (ex
!= EXT_LAST_EXTENT(path
[depth
].p_hdr
)) {
1324 /* next allocated block in this leaf */
1326 *logical
= le32_to_cpu(ex
->ee_block
);
1327 *phys
= ext4_ext_pblock(ex
);
1331 /* go up and search for index to the right */
1332 while (--depth
>= 0) {
1333 ix
= path
[depth
].p_idx
;
1334 if (ix
!= EXT_LAST_INDEX(path
[depth
].p_hdr
))
1338 /* we've gone up to the root and found no index to the right */
1342 /* we've found index to the right, let's
1343 * follow it and find the closest allocated
1344 * block to the right */
1346 block
= ext4_idx_pblock(ix
);
1347 while (++depth
< path
->p_depth
) {
1348 bh
= sb_bread(inode
->i_sb
, block
);
1351 eh
= ext_block_hdr(bh
);
1352 /* subtract from p_depth to get proper eh_depth */
1353 if (ext4_ext_check(inode
, eh
, path
->p_depth
- depth
)) {
1357 ix
= EXT_FIRST_INDEX(eh
);
1358 block
= ext4_idx_pblock(ix
);
1362 bh
= sb_bread(inode
->i_sb
, block
);
1365 eh
= ext_block_hdr(bh
);
1366 if (ext4_ext_check(inode
, eh
, path
->p_depth
- depth
)) {
1370 ex
= EXT_FIRST_EXTENT(eh
);
1371 *logical
= le32_to_cpu(ex
->ee_block
);
1372 *phys
= ext4_ext_pblock(ex
);
1378 * ext4_ext_next_allocated_block:
1379 * returns allocated block in subsequent extent or EXT_MAX_BLOCKS.
1380 * NOTE: it considers block number from index entry as
1381 * allocated block. Thus, index entries have to be consistent
1385 ext4_ext_next_allocated_block(struct ext4_ext_path
*path
)
1389 BUG_ON(path
== NULL
);
1390 depth
= path
->p_depth
;
1392 if (depth
== 0 && path
->p_ext
== NULL
)
1393 return EXT_MAX_BLOCKS
;
1395 while (depth
>= 0) {
1396 if (depth
== path
->p_depth
) {
1398 if (path
[depth
].p_ext
!=
1399 EXT_LAST_EXTENT(path
[depth
].p_hdr
))
1400 return le32_to_cpu(path
[depth
].p_ext
[1].ee_block
);
1403 if (path
[depth
].p_idx
!=
1404 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1405 return le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1410 return EXT_MAX_BLOCKS
;
1414 * ext4_ext_next_leaf_block:
1415 * returns first allocated block from next leaf or EXT_MAX_BLOCKS
1417 static ext4_lblk_t
ext4_ext_next_leaf_block(struct ext4_ext_path
*path
)
1421 BUG_ON(path
== NULL
);
1422 depth
= path
->p_depth
;
1424 /* zero-tree has no leaf blocks at all */
1426 return EXT_MAX_BLOCKS
;
1428 /* go to index block */
1431 while (depth
>= 0) {
1432 if (path
[depth
].p_idx
!=
1433 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1434 return (ext4_lblk_t
)
1435 le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1439 return EXT_MAX_BLOCKS
;
1443 * ext4_ext_correct_indexes:
1444 * if leaf gets modified and modified extent is first in the leaf,
1445 * then we have to correct all indexes above.
1446 * TODO: do we need to correct tree in all cases?
1448 static int ext4_ext_correct_indexes(handle_t
*handle
, struct inode
*inode
,
1449 struct ext4_ext_path
*path
)
1451 struct ext4_extent_header
*eh
;
1452 int depth
= ext_depth(inode
);
1453 struct ext4_extent
*ex
;
1457 eh
= path
[depth
].p_hdr
;
1458 ex
= path
[depth
].p_ext
;
1460 if (unlikely(ex
== NULL
|| eh
== NULL
)) {
1461 EXT4_ERROR_INODE(inode
,
1462 "ex %p == NULL or eh %p == NULL", ex
, eh
);
1467 /* there is no tree at all */
1471 if (ex
!= EXT_FIRST_EXTENT(eh
)) {
1472 /* we correct tree if first leaf got modified only */
1477 * TODO: we need correction if border is smaller than current one
1480 border
= path
[depth
].p_ext
->ee_block
;
1481 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1484 path
[k
].p_idx
->ei_block
= border
;
1485 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1490 /* change all left-side indexes */
1491 if (path
[k
+1].p_idx
!= EXT_FIRST_INDEX(path
[k
+1].p_hdr
))
1493 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1496 path
[k
].p_idx
->ei_block
= border
;
1497 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1506 ext4_can_extents_be_merged(struct inode
*inode
, struct ext4_extent
*ex1
,
1507 struct ext4_extent
*ex2
)
1509 unsigned short ext1_ee_len
, ext2_ee_len
, max_len
;
1512 * Make sure that either both extents are uninitialized, or
1515 if (ext4_ext_is_uninitialized(ex1
) ^ ext4_ext_is_uninitialized(ex2
))
1518 if (ext4_ext_is_uninitialized(ex1
))
1519 max_len
= EXT_UNINIT_MAX_LEN
;
1521 max_len
= EXT_INIT_MAX_LEN
;
1523 ext1_ee_len
= ext4_ext_get_actual_len(ex1
);
1524 ext2_ee_len
= ext4_ext_get_actual_len(ex2
);
1526 if (le32_to_cpu(ex1
->ee_block
) + ext1_ee_len
!=
1527 le32_to_cpu(ex2
->ee_block
))
1531 * To allow future support for preallocated extents to be added
1532 * as an RO_COMPAT feature, refuse to merge to extents if
1533 * this can result in the top bit of ee_len being set.
1535 if (ext1_ee_len
+ ext2_ee_len
> max_len
)
1537 #ifdef AGGRESSIVE_TEST
1538 if (ext1_ee_len
>= 4)
1542 if (ext4_ext_pblock(ex1
) + ext1_ee_len
== ext4_ext_pblock(ex2
))
1548 * This function tries to merge the "ex" extent to the next extent in the tree.
1549 * It always tries to merge towards right. If you want to merge towards
1550 * left, pass "ex - 1" as argument instead of "ex".
1551 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1552 * 1 if they got merged.
1554 static int ext4_ext_try_to_merge_right(struct inode
*inode
,
1555 struct ext4_ext_path
*path
,
1556 struct ext4_extent
*ex
)
1558 struct ext4_extent_header
*eh
;
1559 unsigned int depth
, len
;
1561 int uninitialized
= 0;
1563 depth
= ext_depth(inode
);
1564 BUG_ON(path
[depth
].p_hdr
== NULL
);
1565 eh
= path
[depth
].p_hdr
;
1567 while (ex
< EXT_LAST_EXTENT(eh
)) {
1568 if (!ext4_can_extents_be_merged(inode
, ex
, ex
+ 1))
1570 /* merge with next extent! */
1571 if (ext4_ext_is_uninitialized(ex
))
1573 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1574 + ext4_ext_get_actual_len(ex
+ 1));
1576 ext4_ext_mark_uninitialized(ex
);
1578 if (ex
+ 1 < EXT_LAST_EXTENT(eh
)) {
1579 len
= (EXT_LAST_EXTENT(eh
) - ex
- 1)
1580 * sizeof(struct ext4_extent
);
1581 memmove(ex
+ 1, ex
+ 2, len
);
1583 le16_add_cpu(&eh
->eh_entries
, -1);
1585 WARN_ON(eh
->eh_entries
== 0);
1586 if (!eh
->eh_entries
)
1587 EXT4_ERROR_INODE(inode
, "eh->eh_entries = 0!");
1594 * This function tries to merge the @ex extent to neighbours in the tree.
1595 * return 1 if merge left else 0.
1597 static int ext4_ext_try_to_merge(struct inode
*inode
,
1598 struct ext4_ext_path
*path
,
1599 struct ext4_extent
*ex
) {
1600 struct ext4_extent_header
*eh
;
1605 depth
= ext_depth(inode
);
1606 BUG_ON(path
[depth
].p_hdr
== NULL
);
1607 eh
= path
[depth
].p_hdr
;
1609 if (ex
> EXT_FIRST_EXTENT(eh
))
1610 merge_done
= ext4_ext_try_to_merge_right(inode
, path
, ex
- 1);
1613 ret
= ext4_ext_try_to_merge_right(inode
, path
, ex
);
1619 * check if a portion of the "newext" extent overlaps with an
1622 * If there is an overlap discovered, it updates the length of the newext
1623 * such that there will be no overlap, and then returns 1.
1624 * If there is no overlap found, it returns 0.
1626 static unsigned int ext4_ext_check_overlap(struct inode
*inode
,
1627 struct ext4_extent
*newext
,
1628 struct ext4_ext_path
*path
)
1631 unsigned int depth
, len1
;
1632 unsigned int ret
= 0;
1634 b1
= le32_to_cpu(newext
->ee_block
);
1635 len1
= ext4_ext_get_actual_len(newext
);
1636 depth
= ext_depth(inode
);
1637 if (!path
[depth
].p_ext
)
1639 b2
= le32_to_cpu(path
[depth
].p_ext
->ee_block
);
1642 * get the next allocated block if the extent in the path
1643 * is before the requested block(s)
1646 b2
= ext4_ext_next_allocated_block(path
);
1647 if (b2
== EXT_MAX_BLOCKS
)
1651 /* check for wrap through zero on extent logical start block*/
1652 if (b1
+ len1
< b1
) {
1653 len1
= EXT_MAX_BLOCKS
- b1
;
1654 newext
->ee_len
= cpu_to_le16(len1
);
1658 /* check for overlap */
1659 if (b1
+ len1
> b2
) {
1660 newext
->ee_len
= cpu_to_le16(b2
- b1
);
1668 * ext4_ext_insert_extent:
1669 * tries to merge requsted extent into the existing extent or
1670 * inserts requested extent as new one into the tree,
1671 * creating new leaf in the no-space case.
1673 int ext4_ext_insert_extent(handle_t
*handle
, struct inode
*inode
,
1674 struct ext4_ext_path
*path
,
1675 struct ext4_extent
*newext
, int flag
)
1677 struct ext4_extent_header
*eh
;
1678 struct ext4_extent
*ex
, *fex
;
1679 struct ext4_extent
*nearex
; /* nearest extent */
1680 struct ext4_ext_path
*npath
= NULL
;
1681 int depth
, len
, err
;
1683 unsigned uninitialized
= 0;
1686 if (unlikely(ext4_ext_get_actual_len(newext
) == 0)) {
1687 EXT4_ERROR_INODE(inode
, "ext4_ext_get_actual_len(newext) == 0");
1690 depth
= ext_depth(inode
);
1691 ex
= path
[depth
].p_ext
;
1692 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
1693 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
1697 /* try to insert block into found extent and return */
1698 if (ex
&& !(flag
& EXT4_GET_BLOCKS_PRE_IO
)
1699 && ext4_can_extents_be_merged(inode
, ex
, newext
)) {
1700 ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
1701 ext4_ext_is_uninitialized(newext
),
1702 ext4_ext_get_actual_len(newext
),
1703 le32_to_cpu(ex
->ee_block
),
1704 ext4_ext_is_uninitialized(ex
),
1705 ext4_ext_get_actual_len(ex
),
1706 ext4_ext_pblock(ex
));
1707 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
1712 * ext4_can_extents_be_merged should have checked that either
1713 * both extents are uninitialized, or both aren't. Thus we
1714 * need to check only one of them here.
1716 if (ext4_ext_is_uninitialized(ex
))
1718 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1719 + ext4_ext_get_actual_len(newext
));
1721 ext4_ext_mark_uninitialized(ex
);
1722 eh
= path
[depth
].p_hdr
;
1727 depth
= ext_depth(inode
);
1728 eh
= path
[depth
].p_hdr
;
1729 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
))
1732 /* probably next leaf has space for us? */
1733 fex
= EXT_LAST_EXTENT(eh
);
1734 next
= EXT_MAX_BLOCKS
;
1735 if (le32_to_cpu(newext
->ee_block
) > le32_to_cpu(fex
->ee_block
))
1736 next
= ext4_ext_next_leaf_block(path
);
1737 if (next
!= EXT_MAX_BLOCKS
) {
1738 ext_debug("next leaf block - %d\n", next
);
1739 BUG_ON(npath
!= NULL
);
1740 npath
= ext4_ext_find_extent(inode
, next
, NULL
);
1742 return PTR_ERR(npath
);
1743 BUG_ON(npath
->p_depth
!= path
->p_depth
);
1744 eh
= npath
[depth
].p_hdr
;
1745 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
)) {
1746 ext_debug("next leaf isn't full(%d)\n",
1747 le16_to_cpu(eh
->eh_entries
));
1751 ext_debug("next leaf has no free space(%d,%d)\n",
1752 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
1756 * There is no free space in the found leaf.
1757 * We're gonna add a new leaf in the tree.
1759 if (flag
& EXT4_GET_BLOCKS_PUNCH_OUT_EXT
)
1760 flags
= EXT4_MB_USE_ROOT_BLOCKS
;
1761 err
= ext4_ext_create_new_leaf(handle
, inode
, flags
, path
, newext
);
1764 depth
= ext_depth(inode
);
1765 eh
= path
[depth
].p_hdr
;
1768 nearex
= path
[depth
].p_ext
;
1770 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
1775 /* there is no extent in this leaf, create first one */
1776 ext_debug("first extent in the leaf: %d:%llu:[%d]%d\n",
1777 le32_to_cpu(newext
->ee_block
),
1778 ext4_ext_pblock(newext
),
1779 ext4_ext_is_uninitialized(newext
),
1780 ext4_ext_get_actual_len(newext
));
1781 path
[depth
].p_ext
= EXT_FIRST_EXTENT(eh
);
1782 } else if (le32_to_cpu(newext
->ee_block
)
1783 > le32_to_cpu(nearex
->ee_block
)) {
1784 /* BUG_ON(newext->ee_block == nearex->ee_block); */
1785 if (nearex
!= EXT_LAST_EXTENT(eh
)) {
1786 len
= EXT_MAX_EXTENT(eh
) - nearex
;
1787 len
= (len
- 1) * sizeof(struct ext4_extent
);
1788 len
= len
< 0 ? 0 : len
;
1789 ext_debug("insert %d:%llu:[%d]%d after: nearest 0x%p, "
1790 "move %d from 0x%p to 0x%p\n",
1791 le32_to_cpu(newext
->ee_block
),
1792 ext4_ext_pblock(newext
),
1793 ext4_ext_is_uninitialized(newext
),
1794 ext4_ext_get_actual_len(newext
),
1795 nearex
, len
, nearex
+ 1, nearex
+ 2);
1796 memmove(nearex
+ 2, nearex
+ 1, len
);
1798 path
[depth
].p_ext
= nearex
+ 1;
1800 BUG_ON(newext
->ee_block
== nearex
->ee_block
);
1801 len
= (EXT_MAX_EXTENT(eh
) - nearex
) * sizeof(struct ext4_extent
);
1802 len
= len
< 0 ? 0 : len
;
1803 ext_debug("insert %d:%llu:[%d]%d before: nearest 0x%p, "
1804 "move %d from 0x%p to 0x%p\n",
1805 le32_to_cpu(newext
->ee_block
),
1806 ext4_ext_pblock(newext
),
1807 ext4_ext_is_uninitialized(newext
),
1808 ext4_ext_get_actual_len(newext
),
1809 nearex
, len
, nearex
+ 1, nearex
+ 2);
1810 memmove(nearex
+ 1, nearex
, len
);
1811 path
[depth
].p_ext
= nearex
;
1814 le16_add_cpu(&eh
->eh_entries
, 1);
1815 nearex
= path
[depth
].p_ext
;
1816 nearex
->ee_block
= newext
->ee_block
;
1817 ext4_ext_store_pblock(nearex
, ext4_ext_pblock(newext
));
1818 nearex
->ee_len
= newext
->ee_len
;
1821 /* try to merge extents to the right */
1822 if (!(flag
& EXT4_GET_BLOCKS_PRE_IO
))
1823 ext4_ext_try_to_merge(inode
, path
, nearex
);
1825 /* try to merge extents to the left */
1827 /* time to correct all indexes above */
1828 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
1832 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
1836 ext4_ext_drop_refs(npath
);
1839 ext4_ext_invalidate_cache(inode
);
1843 static int ext4_ext_walk_space(struct inode
*inode
, ext4_lblk_t block
,
1844 ext4_lblk_t num
, ext_prepare_callback func
,
1847 struct ext4_ext_path
*path
= NULL
;
1848 struct ext4_ext_cache cbex
;
1849 struct ext4_extent
*ex
;
1850 ext4_lblk_t next
, start
= 0, end
= 0;
1851 ext4_lblk_t last
= block
+ num
;
1852 int depth
, exists
, err
= 0;
1854 BUG_ON(func
== NULL
);
1855 BUG_ON(inode
== NULL
);
1857 while (block
< last
&& block
!= EXT_MAX_BLOCKS
) {
1859 /* find extent for this block */
1860 down_read(&EXT4_I(inode
)->i_data_sem
);
1861 path
= ext4_ext_find_extent(inode
, block
, path
);
1862 up_read(&EXT4_I(inode
)->i_data_sem
);
1864 err
= PTR_ERR(path
);
1869 depth
= ext_depth(inode
);
1870 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
1871 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
1875 ex
= path
[depth
].p_ext
;
1876 next
= ext4_ext_next_allocated_block(path
);
1880 /* there is no extent yet, so try to allocate
1881 * all requested space */
1884 } else if (le32_to_cpu(ex
->ee_block
) > block
) {
1885 /* need to allocate space before found extent */
1887 end
= le32_to_cpu(ex
->ee_block
);
1888 if (block
+ num
< end
)
1890 } else if (block
>= le32_to_cpu(ex
->ee_block
)
1891 + ext4_ext_get_actual_len(ex
)) {
1892 /* need to allocate space after found extent */
1897 } else if (block
>= le32_to_cpu(ex
->ee_block
)) {
1899 * some part of requested space is covered
1903 end
= le32_to_cpu(ex
->ee_block
)
1904 + ext4_ext_get_actual_len(ex
);
1905 if (block
+ num
< end
)
1911 BUG_ON(end
<= start
);
1914 cbex
.ec_block
= start
;
1915 cbex
.ec_len
= end
- start
;
1918 cbex
.ec_block
= le32_to_cpu(ex
->ee_block
);
1919 cbex
.ec_len
= ext4_ext_get_actual_len(ex
);
1920 cbex
.ec_start
= ext4_ext_pblock(ex
);
1923 if (unlikely(cbex
.ec_len
== 0)) {
1924 EXT4_ERROR_INODE(inode
, "cbex.ec_len == 0");
1928 err
= func(inode
, next
, &cbex
, ex
, cbdata
);
1929 ext4_ext_drop_refs(path
);
1934 if (err
== EXT_REPEAT
)
1936 else if (err
== EXT_BREAK
) {
1941 if (ext_depth(inode
) != depth
) {
1942 /* depth was changed. we have to realloc path */
1947 block
= cbex
.ec_block
+ cbex
.ec_len
;
1951 ext4_ext_drop_refs(path
);
1959 ext4_ext_put_in_cache(struct inode
*inode
, ext4_lblk_t block
,
1960 __u32 len
, ext4_fsblk_t start
)
1962 struct ext4_ext_cache
*cex
;
1964 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1965 cex
= &EXT4_I(inode
)->i_cached_extent
;
1966 cex
->ec_block
= block
;
1968 cex
->ec_start
= start
;
1969 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1973 * ext4_ext_put_gap_in_cache:
1974 * calculate boundaries of the gap that the requested block fits into
1975 * and cache this gap
1978 ext4_ext_put_gap_in_cache(struct inode
*inode
, struct ext4_ext_path
*path
,
1981 int depth
= ext_depth(inode
);
1984 struct ext4_extent
*ex
;
1986 ex
= path
[depth
].p_ext
;
1988 /* there is no extent yet, so gap is [0;-] */
1990 len
= EXT_MAX_BLOCKS
;
1991 ext_debug("cache gap(whole file):");
1992 } else if (block
< le32_to_cpu(ex
->ee_block
)) {
1994 len
= le32_to_cpu(ex
->ee_block
) - block
;
1995 ext_debug("cache gap(before): %u [%u:%u]",
1997 le32_to_cpu(ex
->ee_block
),
1998 ext4_ext_get_actual_len(ex
));
1999 } else if (block
>= le32_to_cpu(ex
->ee_block
)
2000 + ext4_ext_get_actual_len(ex
)) {
2002 lblock
= le32_to_cpu(ex
->ee_block
)
2003 + ext4_ext_get_actual_len(ex
);
2005 next
= ext4_ext_next_allocated_block(path
);
2006 ext_debug("cache gap(after): [%u:%u] %u",
2007 le32_to_cpu(ex
->ee_block
),
2008 ext4_ext_get_actual_len(ex
),
2010 BUG_ON(next
== lblock
);
2011 len
= next
- lblock
;
2017 ext_debug(" -> %u:%lu\n", lblock
, len
);
2018 ext4_ext_put_in_cache(inode
, lblock
, len
, 0);
2022 * ext4_ext_in_cache()
2023 * Checks to see if the given block is in the cache.
2024 * If it is, the cached extent is stored in the given
2025 * cache extent pointer. If the cached extent is a hole,
2026 * this routine should be used instead of
2027 * ext4_ext_in_cache if the calling function needs to
2028 * know the size of the hole.
2030 * @inode: The files inode
2031 * @block: The block to look for in the cache
2032 * @ex: Pointer where the cached extent will be stored
2033 * if it contains block
2035 * Return 0 if cache is invalid; 1 if the cache is valid
2037 static int ext4_ext_check_cache(struct inode
*inode
, ext4_lblk_t block
,
2038 struct ext4_ext_cache
*ex
){
2039 struct ext4_ext_cache
*cex
;
2040 struct ext4_sb_info
*sbi
;
2044 * We borrow i_block_reservation_lock to protect i_cached_extent
2046 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
2047 cex
= &EXT4_I(inode
)->i_cached_extent
;
2048 sbi
= EXT4_SB(inode
->i_sb
);
2050 /* has cache valid data? */
2051 if (cex
->ec_len
== 0)
2054 if (in_range(block
, cex
->ec_block
, cex
->ec_len
)) {
2055 memcpy(ex
, cex
, sizeof(struct ext4_ext_cache
));
2056 ext_debug("%u cached by %u:%u:%llu\n",
2058 cex
->ec_block
, cex
->ec_len
, cex
->ec_start
);
2063 sbi
->extent_cache_misses
++;
2065 sbi
->extent_cache_hits
++;
2066 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
2071 * ext4_ext_in_cache()
2072 * Checks to see if the given block is in the cache.
2073 * If it is, the cached extent is stored in the given
2076 * @inode: The files inode
2077 * @block: The block to look for in the cache
2078 * @ex: Pointer where the cached extent will be stored
2079 * if it contains block
2081 * Return 0 if cache is invalid; 1 if the cache is valid
2084 ext4_ext_in_cache(struct inode
*inode
, ext4_lblk_t block
,
2085 struct ext4_extent
*ex
)
2087 struct ext4_ext_cache cex
;
2090 if (ext4_ext_check_cache(inode
, block
, &cex
)) {
2091 ex
->ee_block
= cpu_to_le32(cex
.ec_block
);
2092 ext4_ext_store_pblock(ex
, cex
.ec_start
);
2093 ex
->ee_len
= cpu_to_le16(cex
.ec_len
);
2103 * removes index from the index block.
2104 * It's used in truncate case only, thus all requests are for
2105 * last index in the block only.
2107 static int ext4_ext_rm_idx(handle_t
*handle
, struct inode
*inode
,
2108 struct ext4_ext_path
*path
)
2113 /* free index block */
2115 leaf
= ext4_idx_pblock(path
->p_idx
);
2116 if (unlikely(path
->p_hdr
->eh_entries
== 0)) {
2117 EXT4_ERROR_INODE(inode
, "path->p_hdr->eh_entries == 0");
2120 err
= ext4_ext_get_access(handle
, inode
, path
);
2123 le16_add_cpu(&path
->p_hdr
->eh_entries
, -1);
2124 err
= ext4_ext_dirty(handle
, inode
, path
);
2127 ext_debug("index is empty, remove it, free block %llu\n", leaf
);
2128 ext4_free_blocks(handle
, inode
, NULL
, leaf
, 1,
2129 EXT4_FREE_BLOCKS_METADATA
| EXT4_FREE_BLOCKS_FORGET
);
2134 * ext4_ext_calc_credits_for_single_extent:
2135 * This routine returns max. credits that needed to insert an extent
2136 * to the extent tree.
2137 * When pass the actual path, the caller should calculate credits
2140 int ext4_ext_calc_credits_for_single_extent(struct inode
*inode
, int nrblocks
,
2141 struct ext4_ext_path
*path
)
2144 int depth
= ext_depth(inode
);
2147 /* probably there is space in leaf? */
2148 if (le16_to_cpu(path
[depth
].p_hdr
->eh_entries
)
2149 < le16_to_cpu(path
[depth
].p_hdr
->eh_max
)) {
2152 * There are some space in the leaf tree, no
2153 * need to account for leaf block credit
2155 * bitmaps and block group descriptor blocks
2156 * and other metadat blocks still need to be
2159 /* 1 bitmap, 1 block group descriptor */
2160 ret
= 2 + EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
2165 return ext4_chunk_trans_blocks(inode
, nrblocks
);
2169 * How many index/leaf blocks need to change/allocate to modify nrblocks?
2171 * if nrblocks are fit in a single extent (chunk flag is 1), then
2172 * in the worse case, each tree level index/leaf need to be changed
2173 * if the tree split due to insert a new extent, then the old tree
2174 * index/leaf need to be updated too
2176 * If the nrblocks are discontiguous, they could cause
2177 * the whole tree split more than once, but this is really rare.
2179 int ext4_ext_index_trans_blocks(struct inode
*inode
, int nrblocks
, int chunk
)
2182 int depth
= ext_depth(inode
);
2192 static int ext4_remove_blocks(handle_t
*handle
, struct inode
*inode
,
2193 struct ext4_extent
*ex
,
2194 ext4_lblk_t from
, ext4_lblk_t to
)
2196 unsigned short ee_len
= ext4_ext_get_actual_len(ex
);
2197 int flags
= EXT4_FREE_BLOCKS_FORGET
;
2199 if (S_ISDIR(inode
->i_mode
) || S_ISLNK(inode
->i_mode
))
2200 flags
|= EXT4_FREE_BLOCKS_METADATA
;
2201 #ifdef EXTENTS_STATS
2203 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2204 spin_lock(&sbi
->s_ext_stats_lock
);
2205 sbi
->s_ext_blocks
+= ee_len
;
2206 sbi
->s_ext_extents
++;
2207 if (ee_len
< sbi
->s_ext_min
)
2208 sbi
->s_ext_min
= ee_len
;
2209 if (ee_len
> sbi
->s_ext_max
)
2210 sbi
->s_ext_max
= ee_len
;
2211 if (ext_depth(inode
) > sbi
->s_depth_max
)
2212 sbi
->s_depth_max
= ext_depth(inode
);
2213 spin_unlock(&sbi
->s_ext_stats_lock
);
2216 if (from
>= le32_to_cpu(ex
->ee_block
)
2217 && to
== le32_to_cpu(ex
->ee_block
) + ee_len
- 1) {
2222 num
= le32_to_cpu(ex
->ee_block
) + ee_len
- from
;
2223 start
= ext4_ext_pblock(ex
) + ee_len
- num
;
2224 ext_debug("free last %u blocks starting %llu\n", num
, start
);
2225 ext4_free_blocks(handle
, inode
, NULL
, start
, num
, flags
);
2226 } else if (from
== le32_to_cpu(ex
->ee_block
)
2227 && to
<= le32_to_cpu(ex
->ee_block
) + ee_len
- 1) {
2233 start
= ext4_ext_pblock(ex
);
2235 ext_debug("free first %u blocks starting %llu\n", num
, start
);
2236 ext4_free_blocks(handle
, inode
, 0, start
, num
, flags
);
2239 printk(KERN_INFO
"strange request: removal(2) "
2240 "%u-%u from %u:%u\n",
2241 from
, to
, le32_to_cpu(ex
->ee_block
), ee_len
);
2248 * ext4_ext_rm_leaf() Removes the extents associated with the
2249 * blocks appearing between "start" and "end", and splits the extents
2250 * if "start" and "end" appear in the same extent
2252 * @handle: The journal handle
2253 * @inode: The files inode
2254 * @path: The path to the leaf
2255 * @start: The first block to remove
2256 * @end: The last block to remove
2259 ext4_ext_rm_leaf(handle_t
*handle
, struct inode
*inode
,
2260 struct ext4_ext_path
*path
, ext4_lblk_t start
,
2263 int err
= 0, correct_index
= 0;
2264 int depth
= ext_depth(inode
), credits
;
2265 struct ext4_extent_header
*eh
;
2266 ext4_lblk_t a
, b
, block
;
2268 ext4_lblk_t ex_ee_block
;
2269 unsigned short ex_ee_len
;
2270 unsigned uninitialized
= 0;
2271 struct ext4_extent
*ex
;
2272 struct ext4_map_blocks map
;
2274 /* the header must be checked already in ext4_ext_remove_space() */
2275 ext_debug("truncate since %u in leaf\n", start
);
2276 if (!path
[depth
].p_hdr
)
2277 path
[depth
].p_hdr
= ext_block_hdr(path
[depth
].p_bh
);
2278 eh
= path
[depth
].p_hdr
;
2279 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
2280 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
2283 /* find where to start removing */
2284 ex
= EXT_LAST_EXTENT(eh
);
2286 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2287 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2289 while (ex
>= EXT_FIRST_EXTENT(eh
) &&
2290 ex_ee_block
+ ex_ee_len
> start
) {
2292 if (ext4_ext_is_uninitialized(ex
))
2297 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block
,
2298 uninitialized
, ex_ee_len
);
2299 path
[depth
].p_ext
= ex
;
2301 a
= ex_ee_block
> start
? ex_ee_block
: start
;
2302 b
= ex_ee_block
+ex_ee_len
- 1 < end
?
2303 ex_ee_block
+ex_ee_len
- 1 : end
;
2305 ext_debug(" border %u:%u\n", a
, b
);
2307 /* If this extent is beyond the end of the hole, skip it */
2308 if (end
<= ex_ee_block
) {
2310 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2311 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2313 } else if (a
!= ex_ee_block
&&
2314 b
!= ex_ee_block
+ ex_ee_len
- 1) {
2316 * If this is a truncate, then this condition should
2317 * never happen because at least one of the end points
2318 * needs to be on the edge of the extent.
2320 if (end
== EXT_MAX_BLOCKS
- 1) {
2321 ext_debug(" bad truncate %u:%u\n",
2329 * else this is a hole punch, so the extent needs to
2330 * be split since neither edge of the hole is on the
2334 map
.m_pblk
= ext4_ext_pblock(ex
);
2335 map
.m_lblk
= ex_ee_block
;
2336 map
.m_len
= b
- ex_ee_block
;
2338 err
= ext4_split_extent(handle
,
2339 inode
, path
, &map
, 0,
2340 EXT4_GET_BLOCKS_PUNCH_OUT_EXT
|
2341 EXT4_GET_BLOCKS_PRE_IO
);
2346 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2348 b
= ex_ee_block
+ex_ee_len
- 1 < end
?
2349 ex_ee_block
+ex_ee_len
- 1 : end
;
2351 /* Then remove tail of this extent */
2352 block
= ex_ee_block
;
2355 } else if (a
!= ex_ee_block
) {
2356 /* remove tail of the extent */
2357 block
= ex_ee_block
;
2359 } else if (b
!= ex_ee_block
+ ex_ee_len
- 1) {
2360 /* remove head of the extent */
2362 num
= ex_ee_block
+ ex_ee_len
- b
;
2365 * If this is a truncate, this condition
2366 * should never happen
2368 if (end
== EXT_MAX_BLOCKS
- 1) {
2369 ext_debug(" bad truncate %u:%u\n",
2375 /* remove whole extent: excellent! */
2376 block
= ex_ee_block
;
2378 if (a
!= ex_ee_block
) {
2379 ext_debug(" bad truncate %u:%u\n",
2385 if (b
!= ex_ee_block
+ ex_ee_len
- 1) {
2386 ext_debug(" bad truncate %u:%u\n",
2394 * 3 for leaf, sb, and inode plus 2 (bmap and group
2395 * descriptor) for each block group; assume two block
2396 * groups plus ex_ee_len/blocks_per_block_group for
2399 credits
= 7 + 2*(ex_ee_len
/EXT4_BLOCKS_PER_GROUP(inode
->i_sb
));
2400 if (ex
== EXT_FIRST_EXTENT(eh
)) {
2402 credits
+= (ext_depth(inode
)) + 1;
2404 credits
+= EXT4_MAXQUOTAS_TRANS_BLOCKS(inode
->i_sb
);
2406 err
= ext4_ext_truncate_extend_restart(handle
, inode
, credits
);
2410 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2414 err
= ext4_remove_blocks(handle
, inode
, ex
, a
, b
);
2419 /* this extent is removed; mark slot entirely unused */
2420 ext4_ext_store_pblock(ex
, 0);
2421 } else if (block
!= ex_ee_block
) {
2423 * If this was a head removal, then we need to update
2424 * the physical block since it is now at a different
2427 ext4_ext_store_pblock(ex
, ext4_ext_pblock(ex
) + (b
-a
));
2430 ex
->ee_block
= cpu_to_le32(block
);
2431 ex
->ee_len
= cpu_to_le16(num
);
2433 * Do not mark uninitialized if all the blocks in the
2434 * extent have been removed.
2436 if (uninitialized
&& num
)
2437 ext4_ext_mark_uninitialized(ex
);
2439 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2444 * If the extent was completely released,
2445 * we need to remove it from the leaf
2448 if (end
!= EXT_MAX_BLOCKS
- 1) {
2450 * For hole punching, we need to scoot all the
2451 * extents up when an extent is removed so that
2452 * we dont have blank extents in the middle
2454 memmove(ex
, ex
+1, (EXT_LAST_EXTENT(eh
) - ex
) *
2455 sizeof(struct ext4_extent
));
2457 /* Now get rid of the one at the end */
2458 memset(EXT_LAST_EXTENT(eh
), 0,
2459 sizeof(struct ext4_extent
));
2461 le16_add_cpu(&eh
->eh_entries
, -1);
2464 ext_debug("new extent: %u:%u:%llu\n", block
, num
,
2465 ext4_ext_pblock(ex
));
2467 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2468 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2471 if (correct_index
&& eh
->eh_entries
)
2472 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2474 /* if this leaf is free, then we should
2475 * remove it from index block above */
2476 if (err
== 0 && eh
->eh_entries
== 0 && path
[depth
].p_bh
!= NULL
)
2477 err
= ext4_ext_rm_idx(handle
, inode
, path
+ depth
);
2484 * ext4_ext_more_to_rm:
2485 * returns 1 if current index has to be freed (even partial)
2488 ext4_ext_more_to_rm(struct ext4_ext_path
*path
)
2490 BUG_ON(path
->p_idx
== NULL
);
2492 if (path
->p_idx
< EXT_FIRST_INDEX(path
->p_hdr
))
2496 * if truncate on deeper level happened, it wasn't partial,
2497 * so we have to consider current index for truncation
2499 if (le16_to_cpu(path
->p_hdr
->eh_entries
) == path
->p_block
)
2504 static int ext4_ext_remove_space(struct inode
*inode
, ext4_lblk_t start
)
2506 struct super_block
*sb
= inode
->i_sb
;
2507 int depth
= ext_depth(inode
);
2508 struct ext4_ext_path
*path
;
2512 ext_debug("truncate since %u\n", start
);
2514 /* probably first extent we're gonna free will be last in block */
2515 handle
= ext4_journal_start(inode
, depth
+ 1);
2517 return PTR_ERR(handle
);
2520 ext4_ext_invalidate_cache(inode
);
2523 * We start scanning from right side, freeing all the blocks
2524 * after i_size and walking into the tree depth-wise.
2526 depth
= ext_depth(inode
);
2527 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 1), GFP_NOFS
);
2529 ext4_journal_stop(handle
);
2532 path
[0].p_depth
= depth
;
2533 path
[0].p_hdr
= ext_inode_hdr(inode
);
2534 if (ext4_ext_check(inode
, path
[0].p_hdr
, depth
)) {
2540 while (i
>= 0 && err
== 0) {
2542 /* this is leaf block */
2543 err
= ext4_ext_rm_leaf(handle
, inode
, path
,
2544 start
, EXT_MAX_BLOCKS
- 1);
2545 /* root level has p_bh == NULL, brelse() eats this */
2546 brelse(path
[i
].p_bh
);
2547 path
[i
].p_bh
= NULL
;
2552 /* this is index block */
2553 if (!path
[i
].p_hdr
) {
2554 ext_debug("initialize header\n");
2555 path
[i
].p_hdr
= ext_block_hdr(path
[i
].p_bh
);
2558 if (!path
[i
].p_idx
) {
2559 /* this level hasn't been touched yet */
2560 path
[i
].p_idx
= EXT_LAST_INDEX(path
[i
].p_hdr
);
2561 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
)+1;
2562 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2564 le16_to_cpu(path
[i
].p_hdr
->eh_entries
));
2566 /* we were already here, see at next index */
2570 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2571 i
, EXT_FIRST_INDEX(path
[i
].p_hdr
),
2573 if (ext4_ext_more_to_rm(path
+ i
)) {
2574 struct buffer_head
*bh
;
2575 /* go to the next level */
2576 ext_debug("move to level %d (block %llu)\n",
2577 i
+ 1, ext4_idx_pblock(path
[i
].p_idx
));
2578 memset(path
+ i
+ 1, 0, sizeof(*path
));
2579 bh
= sb_bread(sb
, ext4_idx_pblock(path
[i
].p_idx
));
2581 /* should we reset i_size? */
2585 if (WARN_ON(i
+ 1 > depth
)) {
2589 if (ext4_ext_check(inode
, ext_block_hdr(bh
),
2594 path
[i
+ 1].p_bh
= bh
;
2596 /* save actual number of indexes since this
2597 * number is changed at the next iteration */
2598 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
);
2601 /* we finished processing this index, go up */
2602 if (path
[i
].p_hdr
->eh_entries
== 0 && i
> 0) {
2603 /* index is empty, remove it;
2604 * handle must be already prepared by the
2605 * truncatei_leaf() */
2606 err
= ext4_ext_rm_idx(handle
, inode
, path
+ i
);
2608 /* root level has p_bh == NULL, brelse() eats this */
2609 brelse(path
[i
].p_bh
);
2610 path
[i
].p_bh
= NULL
;
2612 ext_debug("return to level %d\n", i
);
2616 /* TODO: flexible tree reduction should be here */
2617 if (path
->p_hdr
->eh_entries
== 0) {
2619 * truncate to zero freed all the tree,
2620 * so we need to correct eh_depth
2622 err
= ext4_ext_get_access(handle
, inode
, path
);
2624 ext_inode_hdr(inode
)->eh_depth
= 0;
2625 ext_inode_hdr(inode
)->eh_max
=
2626 cpu_to_le16(ext4_ext_space_root(inode
, 0));
2627 err
= ext4_ext_dirty(handle
, inode
, path
);
2631 ext4_ext_drop_refs(path
);
2635 ext4_journal_stop(handle
);
2641 * called at mount time
2643 void ext4_ext_init(struct super_block
*sb
)
2646 * possible initialization would be here
2649 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
)) {
2650 #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
2651 printk(KERN_INFO
"EXT4-fs: file extents enabled");
2652 #ifdef AGGRESSIVE_TEST
2653 printk(", aggressive tests");
2655 #ifdef CHECK_BINSEARCH
2656 printk(", check binsearch");
2658 #ifdef EXTENTS_STATS
2663 #ifdef EXTENTS_STATS
2664 spin_lock_init(&EXT4_SB(sb
)->s_ext_stats_lock
);
2665 EXT4_SB(sb
)->s_ext_min
= 1 << 30;
2666 EXT4_SB(sb
)->s_ext_max
= 0;
2672 * called at umount time
2674 void ext4_ext_release(struct super_block
*sb
)
2676 if (!EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
))
2679 #ifdef EXTENTS_STATS
2680 if (EXT4_SB(sb
)->s_ext_blocks
&& EXT4_SB(sb
)->s_ext_extents
) {
2681 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2682 printk(KERN_ERR
"EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2683 sbi
->s_ext_blocks
, sbi
->s_ext_extents
,
2684 sbi
->s_ext_blocks
/ sbi
->s_ext_extents
);
2685 printk(KERN_ERR
"EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2686 sbi
->s_ext_min
, sbi
->s_ext_max
, sbi
->s_depth_max
);
2691 /* FIXME!! we need to try to merge to left or right after zero-out */
2692 static int ext4_ext_zeroout(struct inode
*inode
, struct ext4_extent
*ex
)
2694 ext4_fsblk_t ee_pblock
;
2695 unsigned int ee_len
;
2698 ee_len
= ext4_ext_get_actual_len(ex
);
2699 ee_pblock
= ext4_ext_pblock(ex
);
2701 ret
= sb_issue_zeroout(inode
->i_sb
, ee_pblock
, ee_len
, GFP_NOFS
);
2709 * used by extent splitting.
2711 #define EXT4_EXT_MAY_ZEROOUT 0x1 /* safe to zeroout if split fails \
2713 #define EXT4_EXT_MARK_UNINIT1 0x2 /* mark first half uninitialized */
2714 #define EXT4_EXT_MARK_UNINIT2 0x4 /* mark second half uninitialized */
2717 * ext4_split_extent_at() splits an extent at given block.
2719 * @handle: the journal handle
2720 * @inode: the file inode
2721 * @path: the path to the extent
2722 * @split: the logical block where the extent is splitted.
2723 * @split_flags: indicates if the extent could be zeroout if split fails, and
2724 * the states(init or uninit) of new extents.
2725 * @flags: flags used to insert new extent to extent tree.
2728 * Splits extent [a, b] into two extents [a, @split) and [@split, b], states
2729 * of which are deterimined by split_flag.
2731 * There are two cases:
2732 * a> the extent are splitted into two extent.
2733 * b> split is not needed, and just mark the extent.
2735 * return 0 on success.
2737 static int ext4_split_extent_at(handle_t
*handle
,
2738 struct inode
*inode
,
2739 struct ext4_ext_path
*path
,
2744 ext4_fsblk_t newblock
;
2745 ext4_lblk_t ee_block
;
2746 struct ext4_extent
*ex
, newex
, orig_ex
;
2747 struct ext4_extent
*ex2
= NULL
;
2748 unsigned int ee_len
, depth
;
2751 ext_debug("ext4_split_extents_at: inode %lu, logical"
2752 "block %llu\n", inode
->i_ino
, (unsigned long long)split
);
2754 ext4_ext_show_leaf(inode
, path
);
2756 depth
= ext_depth(inode
);
2757 ex
= path
[depth
].p_ext
;
2758 ee_block
= le32_to_cpu(ex
->ee_block
);
2759 ee_len
= ext4_ext_get_actual_len(ex
);
2760 newblock
= split
- ee_block
+ ext4_ext_pblock(ex
);
2762 BUG_ON(split
< ee_block
|| split
>= (ee_block
+ ee_len
));
2764 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2768 if (split
== ee_block
) {
2770 * case b: block @split is the block that the extent begins with
2771 * then we just change the state of the extent, and splitting
2774 if (split_flag
& EXT4_EXT_MARK_UNINIT2
)
2775 ext4_ext_mark_uninitialized(ex
);
2777 ext4_ext_mark_initialized(ex
);
2779 if (!(flags
& EXT4_GET_BLOCKS_PRE_IO
))
2780 ext4_ext_try_to_merge(inode
, path
, ex
);
2782 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2787 memcpy(&orig_ex
, ex
, sizeof(orig_ex
));
2788 ex
->ee_len
= cpu_to_le16(split
- ee_block
);
2789 if (split_flag
& EXT4_EXT_MARK_UNINIT1
)
2790 ext4_ext_mark_uninitialized(ex
);
2793 * path may lead to new leaf, not to original leaf any more
2794 * after ext4_ext_insert_extent() returns,
2796 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2798 goto fix_extent_len
;
2801 ex2
->ee_block
= cpu_to_le32(split
);
2802 ex2
->ee_len
= cpu_to_le16(ee_len
- (split
- ee_block
));
2803 ext4_ext_store_pblock(ex2
, newblock
);
2804 if (split_flag
& EXT4_EXT_MARK_UNINIT2
)
2805 ext4_ext_mark_uninitialized(ex2
);
2807 err
= ext4_ext_insert_extent(handle
, inode
, path
, &newex
, flags
);
2808 if (err
== -ENOSPC
&& (EXT4_EXT_MAY_ZEROOUT
& split_flag
)) {
2809 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2811 goto fix_extent_len
;
2812 /* update the extent length and mark as initialized */
2813 ex
->ee_len
= cpu_to_le32(ee_len
);
2814 ext4_ext_try_to_merge(inode
, path
, ex
);
2815 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2818 goto fix_extent_len
;
2821 ext4_ext_show_leaf(inode
, path
);
2825 ex
->ee_len
= orig_ex
.ee_len
;
2826 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2831 * ext4_split_extents() splits an extent and mark extent which is covered
2832 * by @map as split_flags indicates
2834 * It may result in splitting the extent into multiple extents (upto three)
2835 * There are three possibilities:
2836 * a> There is no split required
2837 * b> Splits in two extents: Split is happening at either end of the extent
2838 * c> Splits in three extents: Somone is splitting in middle of the extent
2841 static int ext4_split_extent(handle_t
*handle
,
2842 struct inode
*inode
,
2843 struct ext4_ext_path
*path
,
2844 struct ext4_map_blocks
*map
,
2848 ext4_lblk_t ee_block
;
2849 struct ext4_extent
*ex
;
2850 unsigned int ee_len
, depth
;
2853 int split_flag1
, flags1
;
2855 depth
= ext_depth(inode
);
2856 ex
= path
[depth
].p_ext
;
2857 ee_block
= le32_to_cpu(ex
->ee_block
);
2858 ee_len
= ext4_ext_get_actual_len(ex
);
2859 uninitialized
= ext4_ext_is_uninitialized(ex
);
2861 if (map
->m_lblk
+ map
->m_len
< ee_block
+ ee_len
) {
2862 split_flag1
= split_flag
& EXT4_EXT_MAY_ZEROOUT
?
2863 EXT4_EXT_MAY_ZEROOUT
: 0;
2864 flags1
= flags
| EXT4_GET_BLOCKS_PRE_IO
;
2866 split_flag1
|= EXT4_EXT_MARK_UNINIT1
|
2867 EXT4_EXT_MARK_UNINIT2
;
2868 err
= ext4_split_extent_at(handle
, inode
, path
,
2869 map
->m_lblk
+ map
->m_len
, split_flag1
, flags1
);
2874 ext4_ext_drop_refs(path
);
2875 path
= ext4_ext_find_extent(inode
, map
->m_lblk
, path
);
2877 return PTR_ERR(path
);
2879 if (map
->m_lblk
>= ee_block
) {
2880 split_flag1
= split_flag
& EXT4_EXT_MAY_ZEROOUT
?
2881 EXT4_EXT_MAY_ZEROOUT
: 0;
2883 split_flag1
|= EXT4_EXT_MARK_UNINIT1
;
2884 if (split_flag
& EXT4_EXT_MARK_UNINIT2
)
2885 split_flag1
|= EXT4_EXT_MARK_UNINIT2
;
2886 err
= ext4_split_extent_at(handle
, inode
, path
,
2887 map
->m_lblk
, split_flag1
, flags
);
2892 ext4_ext_show_leaf(inode
, path
);
2894 return err
? err
: map
->m_len
;
2897 #define EXT4_EXT_ZERO_LEN 7
2899 * This function is called by ext4_ext_map_blocks() if someone tries to write
2900 * to an uninitialized extent. It may result in splitting the uninitialized
2901 * extent into multiple extents (up to three - one initialized and two
2903 * There are three possibilities:
2904 * a> There is no split required: Entire extent should be initialized
2905 * b> Splits in two extents: Write is happening at either end of the extent
2906 * c> Splits in three extents: Somone is writing in middle of the extent
2908 static int ext4_ext_convert_to_initialized(handle_t
*handle
,
2909 struct inode
*inode
,
2910 struct ext4_map_blocks
*map
,
2911 struct ext4_ext_path
*path
)
2913 struct ext4_map_blocks split_map
;
2914 struct ext4_extent zero_ex
;
2915 struct ext4_extent
*ex
;
2916 ext4_lblk_t ee_block
, eof_block
;
2917 unsigned int allocated
, ee_len
, depth
;
2921 ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
2922 "block %llu, max_blocks %u\n", inode
->i_ino
,
2923 (unsigned long long)map
->m_lblk
, map
->m_len
);
2925 eof_block
= (inode
->i_size
+ inode
->i_sb
->s_blocksize
- 1) >>
2926 inode
->i_sb
->s_blocksize_bits
;
2927 if (eof_block
< map
->m_lblk
+ map
->m_len
)
2928 eof_block
= map
->m_lblk
+ map
->m_len
;
2930 depth
= ext_depth(inode
);
2931 ex
= path
[depth
].p_ext
;
2932 ee_block
= le32_to_cpu(ex
->ee_block
);
2933 ee_len
= ext4_ext_get_actual_len(ex
);
2934 allocated
= ee_len
- (map
->m_lblk
- ee_block
);
2936 WARN_ON(map
->m_lblk
< ee_block
);
2938 * It is safe to convert extent to initialized via explicit
2939 * zeroout only if extent is fully insde i_size or new_size.
2941 split_flag
|= ee_block
+ ee_len
<= eof_block
? EXT4_EXT_MAY_ZEROOUT
: 0;
2943 /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
2944 if (ee_len
<= 2*EXT4_EXT_ZERO_LEN
&&
2945 (EXT4_EXT_MAY_ZEROOUT
& split_flag
)) {
2946 err
= ext4_ext_zeroout(inode
, ex
);
2950 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2953 ext4_ext_mark_initialized(ex
);
2954 ext4_ext_try_to_merge(inode
, path
, ex
);
2955 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2961 * 1. split the extent into three extents.
2962 * 2. split the extent into two extents, zeroout the first half.
2963 * 3. split the extent into two extents, zeroout the second half.
2964 * 4. split the extent into two extents with out zeroout.
2966 split_map
.m_lblk
= map
->m_lblk
;
2967 split_map
.m_len
= map
->m_len
;
2969 if (allocated
> map
->m_len
) {
2970 if (allocated
<= EXT4_EXT_ZERO_LEN
&&
2971 (EXT4_EXT_MAY_ZEROOUT
& split_flag
)) {
2974 cpu_to_le32(map
->m_lblk
);
2975 zero_ex
.ee_len
= cpu_to_le16(allocated
);
2976 ext4_ext_store_pblock(&zero_ex
,
2977 ext4_ext_pblock(ex
) + map
->m_lblk
- ee_block
);
2978 err
= ext4_ext_zeroout(inode
, &zero_ex
);
2981 split_map
.m_lblk
= map
->m_lblk
;
2982 split_map
.m_len
= allocated
;
2983 } else if ((map
->m_lblk
- ee_block
+ map
->m_len
<
2984 EXT4_EXT_ZERO_LEN
) &&
2985 (EXT4_EXT_MAY_ZEROOUT
& split_flag
)) {
2987 if (map
->m_lblk
!= ee_block
) {
2988 zero_ex
.ee_block
= ex
->ee_block
;
2989 zero_ex
.ee_len
= cpu_to_le16(map
->m_lblk
-
2991 ext4_ext_store_pblock(&zero_ex
,
2992 ext4_ext_pblock(ex
));
2993 err
= ext4_ext_zeroout(inode
, &zero_ex
);
2998 split_map
.m_lblk
= ee_block
;
2999 split_map
.m_len
= map
->m_lblk
- ee_block
+ map
->m_len
;
3000 allocated
= map
->m_len
;
3004 allocated
= ext4_split_extent(handle
, inode
, path
,
3005 &split_map
, split_flag
, 0);
3010 return err
? err
: allocated
;
3014 * This function is called by ext4_ext_map_blocks() from
3015 * ext4_get_blocks_dio_write() when DIO to write
3016 * to an uninitialized extent.
3018 * Writing to an uninitialized extent may result in splitting the uninitialized
3019 * extent into multiple /initialized uninitialized extents (up to three)
3020 * There are three possibilities:
3021 * a> There is no split required: Entire extent should be uninitialized
3022 * b> Splits in two extents: Write is happening at either end of the extent
3023 * c> Splits in three extents: Somone is writing in middle of the extent
3025 * One of more index blocks maybe needed if the extent tree grow after
3026 * the uninitialized extent split. To prevent ENOSPC occur at the IO
3027 * complete, we need to split the uninitialized extent before DIO submit
3028 * the IO. The uninitialized extent called at this time will be split
3029 * into three uninitialized extent(at most). After IO complete, the part
3030 * being filled will be convert to initialized by the end_io callback function
3031 * via ext4_convert_unwritten_extents().
3033 * Returns the size of uninitialized extent to be written on success.
3035 static int ext4_split_unwritten_extents(handle_t
*handle
,
3036 struct inode
*inode
,
3037 struct ext4_map_blocks
*map
,
3038 struct ext4_ext_path
*path
,
3041 ext4_lblk_t eof_block
;
3042 ext4_lblk_t ee_block
;
3043 struct ext4_extent
*ex
;
3044 unsigned int ee_len
;
3045 int split_flag
= 0, depth
;
3047 ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
3048 "block %llu, max_blocks %u\n", inode
->i_ino
,
3049 (unsigned long long)map
->m_lblk
, map
->m_len
);
3051 eof_block
= (inode
->i_size
+ inode
->i_sb
->s_blocksize
- 1) >>
3052 inode
->i_sb
->s_blocksize_bits
;
3053 if (eof_block
< map
->m_lblk
+ map
->m_len
)
3054 eof_block
= map
->m_lblk
+ map
->m_len
;
3056 * It is safe to convert extent to initialized via explicit
3057 * zeroout only if extent is fully insde i_size or new_size.
3059 depth
= ext_depth(inode
);
3060 ex
= path
[depth
].p_ext
;
3061 ee_block
= le32_to_cpu(ex
->ee_block
);
3062 ee_len
= ext4_ext_get_actual_len(ex
);
3064 split_flag
|= ee_block
+ ee_len
<= eof_block
? EXT4_EXT_MAY_ZEROOUT
: 0;
3065 split_flag
|= EXT4_EXT_MARK_UNINIT2
;
3067 flags
|= EXT4_GET_BLOCKS_PRE_IO
;
3068 return ext4_split_extent(handle
, inode
, path
, map
, split_flag
, flags
);
3071 static int ext4_convert_unwritten_extents_endio(handle_t
*handle
,
3072 struct inode
*inode
,
3073 struct ext4_ext_path
*path
)
3075 struct ext4_extent
*ex
;
3079 depth
= ext_depth(inode
);
3080 ex
= path
[depth
].p_ext
;
3082 ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical"
3083 "block %llu, max_blocks %u\n", inode
->i_ino
,
3084 (unsigned long long)le32_to_cpu(ex
->ee_block
),
3085 ext4_ext_get_actual_len(ex
));
3087 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3090 /* first mark the extent as initialized */
3091 ext4_ext_mark_initialized(ex
);
3093 /* note: ext4_ext_correct_indexes() isn't needed here because
3094 * borders are not changed
3096 ext4_ext_try_to_merge(inode
, path
, ex
);
3098 /* Mark modified extent as dirty */
3099 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
3101 ext4_ext_show_leaf(inode
, path
);
3105 static void unmap_underlying_metadata_blocks(struct block_device
*bdev
,
3106 sector_t block
, int count
)
3109 for (i
= 0; i
< count
; i
++)
3110 unmap_underlying_metadata(bdev
, block
+ i
);
3114 * Handle EOFBLOCKS_FL flag, clearing it if necessary
3116 static int check_eofblocks_fl(handle_t
*handle
, struct inode
*inode
,
3118 struct ext4_ext_path
*path
,
3122 struct ext4_extent_header
*eh
;
3123 struct ext4_extent
*last_ex
;
3125 if (!ext4_test_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
))
3128 depth
= ext_depth(inode
);
3129 eh
= path
[depth
].p_hdr
;
3131 if (unlikely(!eh
->eh_entries
)) {
3132 EXT4_ERROR_INODE(inode
, "eh->eh_entries == 0 and "
3133 "EOFBLOCKS_FL set");
3136 last_ex
= EXT_LAST_EXTENT(eh
);
3138 * We should clear the EOFBLOCKS_FL flag if we are writing the
3139 * last block in the last extent in the file. We test this by
3140 * first checking to see if the caller to
3141 * ext4_ext_get_blocks() was interested in the last block (or
3142 * a block beyond the last block) in the current extent. If
3143 * this turns out to be false, we can bail out from this
3144 * function immediately.
3146 if (lblk
+ len
< le32_to_cpu(last_ex
->ee_block
) +
3147 ext4_ext_get_actual_len(last_ex
))
3150 * If the caller does appear to be planning to write at or
3151 * beyond the end of the current extent, we then test to see
3152 * if the current extent is the last extent in the file, by
3153 * checking to make sure it was reached via the rightmost node
3154 * at each level of the tree.
3156 for (i
= depth
-1; i
>= 0; i
--)
3157 if (path
[i
].p_idx
!= EXT_LAST_INDEX(path
[i
].p_hdr
))
3159 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3160 return ext4_mark_inode_dirty(handle
, inode
);
3164 ext4_ext_handle_uninitialized_extents(handle_t
*handle
, struct inode
*inode
,
3165 struct ext4_map_blocks
*map
,
3166 struct ext4_ext_path
*path
, int flags
,
3167 unsigned int allocated
, ext4_fsblk_t newblock
)
3171 ext4_io_end_t
*io
= EXT4_I(inode
)->cur_aio_dio
;
3173 ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical"
3174 "block %llu, max_blocks %u, flags %d, allocated %u",
3175 inode
->i_ino
, (unsigned long long)map
->m_lblk
, map
->m_len
,
3177 ext4_ext_show_leaf(inode
, path
);
3179 /* get_block() before submit the IO, split the extent */
3180 if ((flags
& EXT4_GET_BLOCKS_PRE_IO
)) {
3181 ret
= ext4_split_unwritten_extents(handle
, inode
, map
,
3184 * Flag the inode(non aio case) or end_io struct (aio case)
3185 * that this IO needs to conversion to written when IO is
3188 if (io
&& !(io
->flag
& EXT4_IO_END_UNWRITTEN
)) {
3189 io
->flag
= EXT4_IO_END_UNWRITTEN
;
3190 atomic_inc(&EXT4_I(inode
)->i_aiodio_unwritten
);
3192 ext4_set_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
3193 if (ext4_should_dioread_nolock(inode
))
3194 map
->m_flags
|= EXT4_MAP_UNINIT
;
3197 /* IO end_io complete, convert the filled extent to written */
3198 if ((flags
& EXT4_GET_BLOCKS_CONVERT
)) {
3199 ret
= ext4_convert_unwritten_extents_endio(handle
, inode
,
3202 ext4_update_inode_fsync_trans(handle
, inode
, 1);
3203 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
,
3209 /* buffered IO case */
3211 * repeat fallocate creation request
3212 * we already have an unwritten extent
3214 if (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
)
3217 /* buffered READ or buffered write_begin() lookup */
3218 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
3220 * We have blocks reserved already. We
3221 * return allocated blocks so that delalloc
3222 * won't do block reservation for us. But
3223 * the buffer head will be unmapped so that
3224 * a read from the block returns 0s.
3226 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
3230 /* buffered write, writepage time, convert*/
3231 ret
= ext4_ext_convert_to_initialized(handle
, inode
, map
, path
);
3233 ext4_update_inode_fsync_trans(handle
, inode
, 1);
3234 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
, path
,
3246 map
->m_flags
|= EXT4_MAP_NEW
;
3248 * if we allocated more blocks than requested
3249 * we need to make sure we unmap the extra block
3250 * allocated. The actual needed block will get
3251 * unmapped later when we find the buffer_head marked
3254 if (allocated
> map
->m_len
) {
3255 unmap_underlying_metadata_blocks(inode
->i_sb
->s_bdev
,
3256 newblock
+ map
->m_len
,
3257 allocated
- map
->m_len
);
3258 allocated
= map
->m_len
;
3262 * If we have done fallocate with the offset that is already
3263 * delayed allocated, we would have block reservation
3264 * and quota reservation done in the delayed write path.
3265 * But fallocate would have already updated quota and block
3266 * count for this offset. So cancel these reservation
3268 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
3269 ext4_da_update_reserve_space(inode
, allocated
, 0);
3272 map
->m_flags
|= EXT4_MAP_MAPPED
;
3274 if (allocated
> map
->m_len
)
3275 allocated
= map
->m_len
;
3276 ext4_ext_show_leaf(inode
, path
);
3277 map
->m_pblk
= newblock
;
3278 map
->m_len
= allocated
;
3281 ext4_ext_drop_refs(path
);
3284 return err
? err
: allocated
;
3288 * Block allocation/map/preallocation routine for extents based files
3291 * Need to be called with
3292 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
3293 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
3295 * return > 0, number of of blocks already mapped/allocated
3296 * if create == 0 and these are pre-allocated blocks
3297 * buffer head is unmapped
3298 * otherwise blocks are mapped
3300 * return = 0, if plain look up failed (blocks have not been allocated)
3301 * buffer head is unmapped
3303 * return < 0, error case.
3305 int ext4_ext_map_blocks(handle_t
*handle
, struct inode
*inode
,
3306 struct ext4_map_blocks
*map
, int flags
)
3308 struct ext4_ext_path
*path
= NULL
;
3309 struct ext4_extent newex
, *ex
;
3310 ext4_fsblk_t newblock
= 0;
3311 int err
= 0, depth
, ret
;
3312 unsigned int allocated
= 0;
3313 unsigned int punched_out
= 0;
3314 unsigned int result
= 0;
3315 struct ext4_allocation_request ar
;
3316 ext4_io_end_t
*io
= EXT4_I(inode
)->cur_aio_dio
;
3317 struct ext4_map_blocks punch_map
;
3319 ext_debug("blocks %u/%u requested for inode %lu\n",
3320 map
->m_lblk
, map
->m_len
, inode
->i_ino
);
3321 trace_ext4_ext_map_blocks_enter(inode
, map
->m_lblk
, map
->m_len
, flags
);
3323 /* check in cache */
3324 if (!(flags
& EXT4_GET_BLOCKS_PUNCH_OUT_EXT
) &&
3325 ext4_ext_in_cache(inode
, map
->m_lblk
, &newex
)) {
3326 if (!newex
.ee_start_lo
&& !newex
.ee_start_hi
) {
3327 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
3329 * block isn't allocated yet and
3330 * user doesn't want to allocate it
3334 /* we should allocate requested block */
3336 /* block is already allocated */
3337 newblock
= map
->m_lblk
3338 - le32_to_cpu(newex
.ee_block
)
3339 + ext4_ext_pblock(&newex
);
3340 /* number of remaining blocks in the extent */
3341 allocated
= ext4_ext_get_actual_len(&newex
) -
3342 (map
->m_lblk
- le32_to_cpu(newex
.ee_block
));
3347 /* find extent for this block */
3348 path
= ext4_ext_find_extent(inode
, map
->m_lblk
, NULL
);
3350 err
= PTR_ERR(path
);
3355 depth
= ext_depth(inode
);
3358 * consistent leaf must not be empty;
3359 * this situation is possible, though, _during_ tree modification;
3360 * this is why assert can't be put in ext4_ext_find_extent()
3362 if (unlikely(path
[depth
].p_ext
== NULL
&& depth
!= 0)) {
3363 EXT4_ERROR_INODE(inode
, "bad extent address "
3364 "lblock: %lu, depth: %d pblock %lld",
3365 (unsigned long) map
->m_lblk
, depth
,
3366 path
[depth
].p_block
);
3371 ex
= path
[depth
].p_ext
;
3373 ext4_lblk_t ee_block
= le32_to_cpu(ex
->ee_block
);
3374 ext4_fsblk_t ee_start
= ext4_ext_pblock(ex
);
3375 unsigned short ee_len
;
3378 * Uninitialized extents are treated as holes, except that
3379 * we split out initialized portions during a write.
3381 ee_len
= ext4_ext_get_actual_len(ex
);
3382 /* if found extent covers block, simply return it */
3383 if (in_range(map
->m_lblk
, ee_block
, ee_len
)) {
3384 newblock
= map
->m_lblk
- ee_block
+ ee_start
;
3385 /* number of remaining blocks in the extent */
3386 allocated
= ee_len
- (map
->m_lblk
- ee_block
);
3387 ext_debug("%u fit into %u:%d -> %llu\n", map
->m_lblk
,
3388 ee_block
, ee_len
, newblock
);
3390 if ((flags
& EXT4_GET_BLOCKS_PUNCH_OUT_EXT
) == 0) {
3392 * Do not put uninitialized extent
3395 if (!ext4_ext_is_uninitialized(ex
)) {
3396 ext4_ext_put_in_cache(inode
, ee_block
,
3400 ret
= ext4_ext_handle_uninitialized_extents(
3401 handle
, inode
, map
, path
, flags
,
3402 allocated
, newblock
);
3407 * Punch out the map length, but only to the
3410 punched_out
= allocated
< map
->m_len
?
3411 allocated
: map
->m_len
;
3414 * Sense extents need to be converted to
3415 * uninitialized, they must fit in an
3416 * uninitialized extent
3418 if (punched_out
> EXT_UNINIT_MAX_LEN
)
3419 punched_out
= EXT_UNINIT_MAX_LEN
;
3421 punch_map
.m_lblk
= map
->m_lblk
;
3422 punch_map
.m_pblk
= newblock
;
3423 punch_map
.m_len
= punched_out
;
3424 punch_map
.m_flags
= 0;
3426 /* Check to see if the extent needs to be split */
3427 if (punch_map
.m_len
!= ee_len
||
3428 punch_map
.m_lblk
!= ee_block
) {
3430 ret
= ext4_split_extent(handle
, inode
,
3431 path
, &punch_map
, 0,
3432 EXT4_GET_BLOCKS_PUNCH_OUT_EXT
|
3433 EXT4_GET_BLOCKS_PRE_IO
);
3440 * find extent for the block at
3441 * the start of the hole
3443 ext4_ext_drop_refs(path
);
3446 path
= ext4_ext_find_extent(inode
,
3449 err
= PTR_ERR(path
);
3454 depth
= ext_depth(inode
);
3455 ex
= path
[depth
].p_ext
;
3456 ee_len
= ext4_ext_get_actual_len(ex
);
3457 ee_block
= le32_to_cpu(ex
->ee_block
);
3458 ee_start
= ext4_ext_pblock(ex
);
3462 ext4_ext_mark_uninitialized(ex
);
3464 ext4_ext_invalidate_cache(inode
);
3466 err
= ext4_ext_rm_leaf(handle
, inode
, path
,
3467 map
->m_lblk
, map
->m_lblk
+ punched_out
);
3469 if (!err
&& path
->p_hdr
->eh_entries
== 0) {
3471 * Punch hole freed all of this sub tree,
3472 * so we need to correct eh_depth
3474 err
= ext4_ext_get_access(handle
, inode
, path
);
3476 ext_inode_hdr(inode
)->eh_depth
= 0;
3477 ext_inode_hdr(inode
)->eh_max
=
3478 cpu_to_le16(ext4_ext_space_root(
3481 err
= ext4_ext_dirty(
3482 handle
, inode
, path
);
3491 * requested block isn't allocated yet;
3492 * we couldn't try to create block if create flag is zero
3494 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
3496 * put just found gap into cache to speed up
3497 * subsequent requests
3499 ext4_ext_put_gap_in_cache(inode
, path
, map
->m_lblk
);
3503 * Okay, we need to do block allocation.
3506 /* find neighbour allocated blocks */
3507 ar
.lleft
= map
->m_lblk
;
3508 err
= ext4_ext_search_left(inode
, path
, &ar
.lleft
, &ar
.pleft
);
3511 ar
.lright
= map
->m_lblk
;
3512 err
= ext4_ext_search_right(inode
, path
, &ar
.lright
, &ar
.pright
);
3517 * See if request is beyond maximum number of blocks we can have in
3518 * a single extent. For an initialized extent this limit is
3519 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
3520 * EXT_UNINIT_MAX_LEN.
3522 if (map
->m_len
> EXT_INIT_MAX_LEN
&&
3523 !(flags
& EXT4_GET_BLOCKS_UNINIT_EXT
))
3524 map
->m_len
= EXT_INIT_MAX_LEN
;
3525 else if (map
->m_len
> EXT_UNINIT_MAX_LEN
&&
3526 (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
))
3527 map
->m_len
= EXT_UNINIT_MAX_LEN
;
3529 /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
3530 newex
.ee_block
= cpu_to_le32(map
->m_lblk
);
3531 newex
.ee_len
= cpu_to_le16(map
->m_len
);
3532 err
= ext4_ext_check_overlap(inode
, &newex
, path
);
3534 allocated
= ext4_ext_get_actual_len(&newex
);
3536 allocated
= map
->m_len
;
3538 /* allocate new block */
3540 ar
.goal
= ext4_ext_find_goal(inode
, path
, map
->m_lblk
);
3541 ar
.logical
= map
->m_lblk
;
3543 if (S_ISREG(inode
->i_mode
))
3544 ar
.flags
= EXT4_MB_HINT_DATA
;
3546 /* disable in-core preallocation for non-regular files */
3548 if (flags
& EXT4_GET_BLOCKS_NO_NORMALIZE
)
3549 ar
.flags
|= EXT4_MB_HINT_NOPREALLOC
;
3550 newblock
= ext4_mb_new_blocks(handle
, &ar
, &err
);
3553 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
3554 ar
.goal
, newblock
, allocated
);
3556 /* try to insert new extent into found leaf and return */
3557 ext4_ext_store_pblock(&newex
, newblock
);
3558 newex
.ee_len
= cpu_to_le16(ar
.len
);
3559 /* Mark uninitialized */
3560 if (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
){
3561 ext4_ext_mark_uninitialized(&newex
);
3563 * io_end structure was created for every IO write to an
3564 * uninitialized extent. To avoid unnecessary conversion,
3565 * here we flag the IO that really needs the conversion.
3566 * For non asycn direct IO case, flag the inode state
3567 * that we need to perform conversion when IO is done.
3569 if ((flags
& EXT4_GET_BLOCKS_PRE_IO
)) {
3570 if (io
&& !(io
->flag
& EXT4_IO_END_UNWRITTEN
)) {
3571 io
->flag
= EXT4_IO_END_UNWRITTEN
;
3572 atomic_inc(&EXT4_I(inode
)->i_aiodio_unwritten
);
3574 ext4_set_inode_state(inode
,
3575 EXT4_STATE_DIO_UNWRITTEN
);
3577 if (ext4_should_dioread_nolock(inode
))
3578 map
->m_flags
|= EXT4_MAP_UNINIT
;
3581 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
, path
, ar
.len
);
3583 err
= ext4_ext_insert_extent(handle
, inode
, path
,
3586 int fb_flags
= flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
?
3587 EXT4_FREE_BLOCKS_NO_QUOT_UPDATE
: 0;
3588 /* free data blocks we just allocated */
3589 /* not a good idea to call discard here directly,
3590 * but otherwise we'd need to call it every free() */
3591 ext4_discard_preallocations(inode
);
3592 ext4_free_blocks(handle
, inode
, NULL
, ext4_ext_pblock(&newex
),
3593 ext4_ext_get_actual_len(&newex
), fb_flags
);
3597 /* previous routine could use block we allocated */
3598 newblock
= ext4_ext_pblock(&newex
);
3599 allocated
= ext4_ext_get_actual_len(&newex
);
3600 if (allocated
> map
->m_len
)
3601 allocated
= map
->m_len
;
3602 map
->m_flags
|= EXT4_MAP_NEW
;
3605 * Update reserved blocks/metadata blocks after successful
3606 * block allocation which had been deferred till now.
3608 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
3609 ext4_da_update_reserve_space(inode
, allocated
, 1);
3612 * Cache the extent and update transaction to commit on fdatasync only
3613 * when it is _not_ an uninitialized extent.
3615 if ((flags
& EXT4_GET_BLOCKS_UNINIT_EXT
) == 0) {
3616 ext4_ext_put_in_cache(inode
, map
->m_lblk
, allocated
, newblock
);
3617 ext4_update_inode_fsync_trans(handle
, inode
, 1);
3619 ext4_update_inode_fsync_trans(handle
, inode
, 0);
3621 if (allocated
> map
->m_len
)
3622 allocated
= map
->m_len
;
3623 ext4_ext_show_leaf(inode
, path
);
3624 map
->m_flags
|= EXT4_MAP_MAPPED
;
3625 map
->m_pblk
= newblock
;
3626 map
->m_len
= allocated
;
3629 ext4_ext_drop_refs(path
);
3632 trace_ext4_ext_map_blocks_exit(inode
, map
->m_lblk
,
3633 newblock
, map
->m_len
, err
? err
: allocated
);
3635 result
= (flags
& EXT4_GET_BLOCKS_PUNCH_OUT_EXT
) ?
3636 punched_out
: allocated
;
3638 return err
? err
: result
;
3641 void ext4_ext_truncate(struct inode
*inode
)
3643 struct address_space
*mapping
= inode
->i_mapping
;
3644 struct super_block
*sb
= inode
->i_sb
;
3645 ext4_lblk_t last_block
;
3650 * finish any pending end_io work so we won't run the risk of
3651 * converting any truncated blocks to initialized later
3653 ext4_flush_completed_IO(inode
);
3656 * probably first extent we're gonna free will be last in block
3658 err
= ext4_writepage_trans_blocks(inode
);
3659 handle
= ext4_journal_start(inode
, err
);
3663 if (inode
->i_size
& (sb
->s_blocksize
- 1))
3664 ext4_block_truncate_page(handle
, mapping
, inode
->i_size
);
3666 if (ext4_orphan_add(handle
, inode
))
3669 down_write(&EXT4_I(inode
)->i_data_sem
);
3670 ext4_ext_invalidate_cache(inode
);
3672 ext4_discard_preallocations(inode
);
3675 * TODO: optimization is possible here.
3676 * Probably we need not scan at all,
3677 * because page truncation is enough.
3680 /* we have to know where to truncate from in crash case */
3681 EXT4_I(inode
)->i_disksize
= inode
->i_size
;
3682 ext4_mark_inode_dirty(handle
, inode
);
3684 last_block
= (inode
->i_size
+ sb
->s_blocksize
- 1)
3685 >> EXT4_BLOCK_SIZE_BITS(sb
);
3686 err
= ext4_ext_remove_space(inode
, last_block
);
3688 /* In a multi-transaction truncate, we only make the final
3689 * transaction synchronous.
3692 ext4_handle_sync(handle
);
3694 up_write(&EXT4_I(inode
)->i_data_sem
);
3698 * If this was a simple ftruncate() and the file will remain alive,
3699 * then we need to clear up the orphan record which we created above.
3700 * However, if this was a real unlink then we were called by
3701 * ext4_delete_inode(), and we allow that function to clean up the
3702 * orphan info for us.
3705 ext4_orphan_del(handle
, inode
);
3707 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3708 ext4_mark_inode_dirty(handle
, inode
);
3709 ext4_journal_stop(handle
);
3712 static void ext4_falloc_update_inode(struct inode
*inode
,
3713 int mode
, loff_t new_size
, int update_ctime
)
3715 struct timespec now
;
3718 now
= current_fs_time(inode
->i_sb
);
3719 if (!timespec_equal(&inode
->i_ctime
, &now
))
3720 inode
->i_ctime
= now
;
3723 * Update only when preallocation was requested beyond
3726 if (!(mode
& FALLOC_FL_KEEP_SIZE
)) {
3727 if (new_size
> i_size_read(inode
))
3728 i_size_write(inode
, new_size
);
3729 if (new_size
> EXT4_I(inode
)->i_disksize
)
3730 ext4_update_i_disksize(inode
, new_size
);
3733 * Mark that we allocate beyond EOF so the subsequent truncate
3734 * can proceed even if the new size is the same as i_size.
3736 if (new_size
> i_size_read(inode
))
3737 ext4_set_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3743 * preallocate space for a file. This implements ext4's fallocate file
3744 * operation, which gets called from sys_fallocate system call.
3745 * For block-mapped files, posix_fallocate should fall back to the method
3746 * of writing zeroes to the required new blocks (the same behavior which is
3747 * expected for file systems which do not support fallocate() system call).
3749 long ext4_fallocate(struct file
*file
, int mode
, loff_t offset
, loff_t len
)
3751 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
3754 unsigned int max_blocks
;
3758 struct ext4_map_blocks map
;
3759 unsigned int credits
, blkbits
= inode
->i_blkbits
;
3762 * currently supporting (pre)allocate mode for extent-based
3765 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
3768 /* Return error if mode is not supported */
3769 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
))
3772 if (mode
& FALLOC_FL_PUNCH_HOLE
)
3773 return ext4_punch_hole(file
, offset
, len
);
3775 trace_ext4_fallocate_enter(inode
, offset
, len
, mode
);
3776 map
.m_lblk
= offset
>> blkbits
;
3778 * We can't just convert len to max_blocks because
3779 * If blocksize = 4096 offset = 3072 and len = 2048
3781 max_blocks
= (EXT4_BLOCK_ALIGN(len
+ offset
, blkbits
) >> blkbits
)
3784 * credits to insert 1 extent into extent tree
3786 credits
= ext4_chunk_trans_blocks(inode
, max_blocks
);
3787 mutex_lock(&inode
->i_mutex
);
3788 ret
= inode_newsize_ok(inode
, (len
+ offset
));
3790 mutex_unlock(&inode
->i_mutex
);
3791 trace_ext4_fallocate_exit(inode
, offset
, max_blocks
, ret
);
3795 while (ret
>= 0 && ret
< max_blocks
) {
3796 map
.m_lblk
= map
.m_lblk
+ ret
;
3797 map
.m_len
= max_blocks
= max_blocks
- ret
;
3798 handle
= ext4_journal_start(inode
, credits
);
3799 if (IS_ERR(handle
)) {
3800 ret
= PTR_ERR(handle
);
3803 ret
= ext4_map_blocks(handle
, inode
, &map
,
3804 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT
|
3805 EXT4_GET_BLOCKS_NO_NORMALIZE
);
3809 printk(KERN_ERR
"%s: ext4_ext_map_blocks "
3810 "returned error inode#%lu, block=%u, "
3811 "max_blocks=%u", __func__
,
3812 inode
->i_ino
, map
.m_lblk
, max_blocks
);
3814 ext4_mark_inode_dirty(handle
, inode
);
3815 ret2
= ext4_journal_stop(handle
);
3818 if ((map
.m_lblk
+ ret
) >= (EXT4_BLOCK_ALIGN(offset
+ len
,
3819 blkbits
) >> blkbits
))
3820 new_size
= offset
+ len
;
3822 new_size
= (map
.m_lblk
+ ret
) << blkbits
;
3824 ext4_falloc_update_inode(inode
, mode
, new_size
,
3825 (map
.m_flags
& EXT4_MAP_NEW
));
3826 ext4_mark_inode_dirty(handle
, inode
);
3827 ret2
= ext4_journal_stop(handle
);
3831 if (ret
== -ENOSPC
&&
3832 ext4_should_retry_alloc(inode
->i_sb
, &retries
)) {
3836 mutex_unlock(&inode
->i_mutex
);
3837 trace_ext4_fallocate_exit(inode
, offset
, max_blocks
,
3838 ret
> 0 ? ret2
: ret
);
3839 return ret
> 0 ? ret2
: ret
;
3843 * This function convert a range of blocks to written extents
3844 * The caller of this function will pass the start offset and the size.
3845 * all unwritten extents within this range will be converted to
3848 * This function is called from the direct IO end io call back
3849 * function, to convert the fallocated extents after IO is completed.
3850 * Returns 0 on success.
3852 int ext4_convert_unwritten_extents(struct inode
*inode
, loff_t offset
,
3856 unsigned int max_blocks
;
3859 struct ext4_map_blocks map
;
3860 unsigned int credits
, blkbits
= inode
->i_blkbits
;
3862 map
.m_lblk
= offset
>> blkbits
;
3864 * We can't just convert len to max_blocks because
3865 * If blocksize = 4096 offset = 3072 and len = 2048
3867 max_blocks
= ((EXT4_BLOCK_ALIGN(len
+ offset
, blkbits
) >> blkbits
) -
3870 * credits to insert 1 extent into extent tree
3872 credits
= ext4_chunk_trans_blocks(inode
, max_blocks
);
3873 while (ret
>= 0 && ret
< max_blocks
) {
3875 map
.m_len
= (max_blocks
-= ret
);
3876 handle
= ext4_journal_start(inode
, credits
);
3877 if (IS_ERR(handle
)) {
3878 ret
= PTR_ERR(handle
);
3881 ret
= ext4_map_blocks(handle
, inode
, &map
,
3882 EXT4_GET_BLOCKS_IO_CONVERT_EXT
);
3885 printk(KERN_ERR
"%s: ext4_ext_map_blocks "
3886 "returned error inode#%lu, block=%u, "
3887 "max_blocks=%u", __func__
,
3888 inode
->i_ino
, map
.m_lblk
, map
.m_len
);
3890 ext4_mark_inode_dirty(handle
, inode
);
3891 ret2
= ext4_journal_stop(handle
);
3892 if (ret
<= 0 || ret2
)
3895 return ret
> 0 ? ret2
: ret
;
3899 * Callback function called for each extent to gather FIEMAP information.
3901 static int ext4_ext_fiemap_cb(struct inode
*inode
, ext4_lblk_t next
,
3902 struct ext4_ext_cache
*newex
, struct ext4_extent
*ex
,
3910 struct fiemap_extent_info
*fieinfo
= data
;
3911 unsigned char blksize_bits
;
3913 blksize_bits
= inode
->i_sb
->s_blocksize_bits
;
3914 logical
= (__u64
)newex
->ec_block
<< blksize_bits
;
3916 if (newex
->ec_start
== 0) {
3918 * No extent in extent-tree contains block @newex->ec_start,
3919 * then the block may stay in 1)a hole or 2)delayed-extent.
3921 * Holes or delayed-extents are processed as follows.
3922 * 1. lookup dirty pages with specified range in pagecache.
3923 * If no page is got, then there is no delayed-extent and
3924 * return with EXT_CONTINUE.
3925 * 2. find the 1st mapped buffer,
3926 * 3. check if the mapped buffer is both in the request range
3927 * and a delayed buffer. If not, there is no delayed-extent,
3929 * 4. a delayed-extent is found, the extent will be collected.
3931 ext4_lblk_t end
= 0;
3932 pgoff_t last_offset
;
3935 pgoff_t start_index
= 0;
3936 struct page
**pages
= NULL
;
3937 struct buffer_head
*bh
= NULL
;
3938 struct buffer_head
*head
= NULL
;
3939 unsigned int nr_pages
= PAGE_SIZE
/ sizeof(struct page
*);
3941 pages
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
3945 offset
= logical
>> PAGE_SHIFT
;
3947 last_offset
= offset
;
3949 ret
= find_get_pages_tag(inode
->i_mapping
, &offset
,
3950 PAGECACHE_TAG_DIRTY
, nr_pages
, pages
);
3952 if (!(flags
& FIEMAP_EXTENT_DELALLOC
)) {
3953 /* First time, try to find a mapped buffer. */
3956 for (index
= 0; index
< ret
; index
++)
3957 page_cache_release(pages
[index
]);
3960 return EXT_CONTINUE
;
3965 /* Try to find the 1st mapped buffer. */
3966 end
= ((__u64
)pages
[index
]->index
<< PAGE_SHIFT
) >>
3968 if (!page_has_buffers(pages
[index
]))
3970 head
= page_buffers(pages
[index
]);
3977 if (end
>= newex
->ec_block
+
3979 /* The buffer is out of
3980 * the request range.
3984 if (buffer_mapped(bh
) &&
3985 end
>= newex
->ec_block
) {
3986 start_index
= index
- 1;
3987 /* get the 1st mapped buffer. */
3988 goto found_mapped_buffer
;
3991 bh
= bh
->b_this_page
;
3993 } while (bh
!= head
);
3995 /* No mapped buffer in the range found in this page,
3996 * We need to look up next page.
3999 /* There is no page left, but we need to limit
4002 newex
->ec_len
= end
- newex
->ec_block
;
4007 /*Find contiguous delayed buffers. */
4008 if (ret
> 0 && pages
[0]->index
== last_offset
)
4009 head
= page_buffers(pages
[0]);
4015 found_mapped_buffer
:
4016 if (bh
!= NULL
&& buffer_delay(bh
)) {
4017 /* 1st or contiguous delayed buffer found. */
4018 if (!(flags
& FIEMAP_EXTENT_DELALLOC
)) {
4020 * 1st delayed buffer found, record
4021 * the start of extent.
4023 flags
|= FIEMAP_EXTENT_DELALLOC
;
4024 newex
->ec_block
= end
;
4025 logical
= (__u64
)end
<< blksize_bits
;
4027 /* Find contiguous delayed buffers. */
4029 if (!buffer_delay(bh
))
4030 goto found_delayed_extent
;
4031 bh
= bh
->b_this_page
;
4033 } while (bh
!= head
);
4035 for (; index
< ret
; index
++) {
4036 if (!page_has_buffers(pages
[index
])) {
4040 head
= page_buffers(pages
[index
]);
4046 if (pages
[index
]->index
!=
4047 pages
[start_index
]->index
+ index
4049 /* Blocks are not contiguous. */
4055 if (!buffer_delay(bh
))
4056 /* Delayed-extent ends. */
4057 goto found_delayed_extent
;
4058 bh
= bh
->b_this_page
;
4060 } while (bh
!= head
);
4062 } else if (!(flags
& FIEMAP_EXTENT_DELALLOC
))
4066 found_delayed_extent
:
4067 newex
->ec_len
= min(end
- newex
->ec_block
,
4068 (ext4_lblk_t
)EXT_INIT_MAX_LEN
);
4069 if (ret
== nr_pages
&& bh
!= NULL
&&
4070 newex
->ec_len
< EXT_INIT_MAX_LEN
&&
4072 /* Have not collected an extent and continue. */
4073 for (index
= 0; index
< ret
; index
++)
4074 page_cache_release(pages
[index
]);
4078 for (index
= 0; index
< ret
; index
++)
4079 page_cache_release(pages
[index
]);
4083 physical
= (__u64
)newex
->ec_start
<< blksize_bits
;
4084 length
= (__u64
)newex
->ec_len
<< blksize_bits
;
4086 if (ex
&& ext4_ext_is_uninitialized(ex
))
4087 flags
|= FIEMAP_EXTENT_UNWRITTEN
;
4089 if (next
== EXT_MAX_BLOCKS
)
4090 flags
|= FIEMAP_EXTENT_LAST
;
4092 ret
= fiemap_fill_next_extent(fieinfo
, logical
, physical
,
4098 return EXT_CONTINUE
;
4101 /* fiemap flags we can handle specified here */
4102 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
4104 static int ext4_xattr_fiemap(struct inode
*inode
,
4105 struct fiemap_extent_info
*fieinfo
)
4109 __u32 flags
= FIEMAP_EXTENT_LAST
;
4110 int blockbits
= inode
->i_sb
->s_blocksize_bits
;
4114 if (ext4_test_inode_state(inode
, EXT4_STATE_XATTR
)) {
4115 struct ext4_iloc iloc
;
4116 int offset
; /* offset of xattr in inode */
4118 error
= ext4_get_inode_loc(inode
, &iloc
);
4121 physical
= iloc
.bh
->b_blocknr
<< blockbits
;
4122 offset
= EXT4_GOOD_OLD_INODE_SIZE
+
4123 EXT4_I(inode
)->i_extra_isize
;
4125 length
= EXT4_SB(inode
->i_sb
)->s_inode_size
- offset
;
4126 flags
|= FIEMAP_EXTENT_DATA_INLINE
;
4128 } else { /* external block */
4129 physical
= EXT4_I(inode
)->i_file_acl
<< blockbits
;
4130 length
= inode
->i_sb
->s_blocksize
;
4134 error
= fiemap_fill_next_extent(fieinfo
, 0, physical
,
4136 return (error
< 0 ? error
: 0);
4140 * ext4_ext_punch_hole
4142 * Punches a hole of "length" bytes in a file starting
4145 * @inode: The inode of the file to punch a hole in
4146 * @offset: The starting byte offset of the hole
4147 * @length: The length of the hole
4149 * Returns the number of blocks removed or negative on err
4151 int ext4_ext_punch_hole(struct file
*file
, loff_t offset
, loff_t length
)
4153 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
4154 struct super_block
*sb
= inode
->i_sb
;
4155 struct ext4_ext_cache cache_ex
;
4156 ext4_lblk_t first_block
, last_block
, num_blocks
, iblock
, max_blocks
;
4157 struct address_space
*mapping
= inode
->i_mapping
;
4158 struct ext4_map_blocks map
;
4160 loff_t first_block_offset
, last_block_offset
, block_len
;
4161 loff_t first_page
, last_page
, first_page_offset
, last_page_offset
;
4162 int ret
, credits
, blocks_released
, err
= 0;
4164 first_block
= (offset
+ sb
->s_blocksize
- 1) >>
4165 EXT4_BLOCK_SIZE_BITS(sb
);
4166 last_block
= (offset
+ length
) >> EXT4_BLOCK_SIZE_BITS(sb
);
4168 first_block_offset
= first_block
<< EXT4_BLOCK_SIZE_BITS(sb
);
4169 last_block_offset
= last_block
<< EXT4_BLOCK_SIZE_BITS(sb
);
4171 first_page
= (offset
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
;
4172 last_page
= (offset
+ length
) >> PAGE_CACHE_SHIFT
;
4174 first_page_offset
= first_page
<< PAGE_CACHE_SHIFT
;
4175 last_page_offset
= last_page
<< PAGE_CACHE_SHIFT
;
4178 * Write out all dirty pages to avoid race conditions
4179 * Then release them.
4181 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
4182 err
= filemap_write_and_wait_range(mapping
,
4183 first_page_offset
== 0 ? 0 : first_page_offset
-1,
4190 /* Now release the pages */
4191 if (last_page_offset
> first_page_offset
) {
4192 truncate_inode_pages_range(mapping
, first_page_offset
,
4193 last_page_offset
-1);
4196 /* finish any pending end_io work */
4197 ext4_flush_completed_IO(inode
);
4199 credits
= ext4_writepage_trans_blocks(inode
);
4200 handle
= ext4_journal_start(inode
, credits
);
4202 return PTR_ERR(handle
);
4204 err
= ext4_orphan_add(handle
, inode
);
4209 * Now we need to zero out the un block aligned data.
4210 * If the file is smaller than a block, just
4211 * zero out the middle
4213 if (first_block
> last_block
)
4214 ext4_block_zero_page_range(handle
, mapping
, offset
, length
);
4216 /* zero out the head of the hole before the first block */
4217 block_len
= first_block_offset
- offset
;
4219 ext4_block_zero_page_range(handle
, mapping
,
4222 /* zero out the tail of the hole after the last block */
4223 block_len
= offset
+ length
- last_block_offset
;
4224 if (block_len
> 0) {
4225 ext4_block_zero_page_range(handle
, mapping
,
4226 last_block_offset
, block_len
);
4230 /* If there are no blocks to remove, return now */
4231 if (first_block
>= last_block
)
4234 down_write(&EXT4_I(inode
)->i_data_sem
);
4235 ext4_ext_invalidate_cache(inode
);
4236 ext4_discard_preallocations(inode
);
4239 * Loop over all the blocks and identify blocks
4240 * that need to be punched out
4242 iblock
= first_block
;
4243 blocks_released
= 0;
4244 while (iblock
< last_block
) {
4245 max_blocks
= last_block
- iblock
;
4247 memset(&map
, 0, sizeof(map
));
4248 map
.m_lblk
= iblock
;
4249 map
.m_len
= max_blocks
;
4250 ret
= ext4_ext_map_blocks(handle
, inode
, &map
,
4251 EXT4_GET_BLOCKS_PUNCH_OUT_EXT
);
4254 blocks_released
+= ret
;
4256 } else if (ret
== 0) {
4258 * If map blocks could not find the block,
4259 * then it is in a hole. If the hole was
4260 * not already cached, then map blocks should
4261 * put it in the cache. So we can get the hole
4264 memset(&cache_ex
, 0, sizeof(cache_ex
));
4265 if ((ext4_ext_check_cache(inode
, iblock
, &cache_ex
)) &&
4266 !cache_ex
.ec_start
) {
4268 /* The hole is cached */
4269 num_blocks
= cache_ex
.ec_block
+
4270 cache_ex
.ec_len
- iblock
;
4273 /* The block could not be identified */
4278 /* Map blocks error */
4283 if (num_blocks
== 0) {
4284 /* This condition should never happen */
4285 ext_debug("Block lookup failed");
4290 iblock
+= num_blocks
;
4293 if (blocks_released
> 0) {
4294 ext4_ext_invalidate_cache(inode
);
4295 ext4_discard_preallocations(inode
);
4299 ext4_handle_sync(handle
);
4301 up_write(&EXT4_I(inode
)->i_data_sem
);
4304 ext4_orphan_del(handle
, inode
);
4305 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
4306 ext4_mark_inode_dirty(handle
, inode
);
4307 ext4_journal_stop(handle
);
4310 int ext4_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
4311 __u64 start
, __u64 len
)
4313 ext4_lblk_t start_blk
;
4316 /* fallback to generic here if not in extents fmt */
4317 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4318 return generic_block_fiemap(inode
, fieinfo
, start
, len
,
4321 if (fiemap_check_flags(fieinfo
, EXT4_FIEMAP_FLAGS
))
4324 if (fieinfo
->fi_flags
& FIEMAP_FLAG_XATTR
) {
4325 error
= ext4_xattr_fiemap(inode
, fieinfo
);
4327 ext4_lblk_t len_blks
;
4330 start_blk
= start
>> inode
->i_sb
->s_blocksize_bits
;
4331 last_blk
= (start
+ len
- 1) >> inode
->i_sb
->s_blocksize_bits
;
4332 if (last_blk
>= EXT_MAX_BLOCKS
)
4333 last_blk
= EXT_MAX_BLOCKS
-1;
4334 len_blks
= ((ext4_lblk_t
) last_blk
) - start_blk
+ 1;
4337 * Walk the extent tree gathering extent information.
4338 * ext4_ext_fiemap_cb will push extents back to user.
4340 error
= ext4_ext_walk_space(inode
, start_blk
, len_blks
,
4341 ext4_ext_fiemap_cb
, fieinfo
);