2 * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
3 * Written by Alex Tomas <alex@clusterfs.com>
5 * Architecture independence:
6 * Copyright (c) 2005, Bull S.A.
7 * Written by Pierre Peiffer <pierre.peiffer@bull.net>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public Licens
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
24 * Extents support for EXT4
27 * - ext4*_error() should be used in some situations
28 * - analyze all BUG()/BUG_ON(), use -EIO where appropriate
29 * - smart tree reduction
32 #include <linux/module.h>
34 #include <linux/time.h>
35 #include <linux/jbd2.h>
36 #include <linux/highuid.h>
37 #include <linux/pagemap.h>
38 #include <linux/quotaops.h>
39 #include <linux/string.h>
40 #include <linux/slab.h>
41 #include <linux/falloc.h>
42 #include <asm/uaccess.h>
43 #include <linux/fiemap.h>
44 #include "ext4_jbd2.h"
45 #include "ext4_extents.h"
50 * combine low and high parts of physical block number into ext4_fsblk_t
52 static ext4_fsblk_t
ext_pblock(struct ext4_extent
*ex
)
56 block
= le32_to_cpu(ex
->ee_start_lo
);
57 block
|= ((ext4_fsblk_t
) le16_to_cpu(ex
->ee_start_hi
) << 31) << 1;
63 * combine low and high parts of a leaf physical block number into ext4_fsblk_t
65 ext4_fsblk_t
idx_pblock(struct ext4_extent_idx
*ix
)
69 block
= le32_to_cpu(ix
->ei_leaf_lo
);
70 block
|= ((ext4_fsblk_t
) le16_to_cpu(ix
->ei_leaf_hi
) << 31) << 1;
75 * ext4_ext_store_pblock:
76 * stores a large physical block number into an extent struct,
77 * breaking it into parts
79 void ext4_ext_store_pblock(struct ext4_extent
*ex
, ext4_fsblk_t pb
)
81 ex
->ee_start_lo
= cpu_to_le32((unsigned long) (pb
& 0xffffffff));
82 ex
->ee_start_hi
= cpu_to_le16((unsigned long) ((pb
>> 31) >> 1) & 0xffff);
86 * ext4_idx_store_pblock:
87 * stores a large physical block number into an index struct,
88 * breaking it into parts
90 static void ext4_idx_store_pblock(struct ext4_extent_idx
*ix
, ext4_fsblk_t pb
)
92 ix
->ei_leaf_lo
= cpu_to_le32((unsigned long) (pb
& 0xffffffff));
93 ix
->ei_leaf_hi
= cpu_to_le16((unsigned long) ((pb
>> 31) >> 1) & 0xffff);
96 static int ext4_ext_journal_restart(handle_t
*handle
, int needed
)
100 if (!ext4_handle_valid(handle
))
102 if (handle
->h_buffer_credits
> needed
)
104 err
= ext4_journal_extend(handle
, needed
);
107 return ext4_journal_restart(handle
, needed
);
115 static int ext4_ext_get_access(handle_t
*handle
, struct inode
*inode
,
116 struct ext4_ext_path
*path
)
119 /* path points to block */
120 return ext4_journal_get_write_access(handle
, path
->p_bh
);
122 /* path points to leaf/index in inode body */
123 /* we use in-core data, no need to protect them */
133 static int ext4_ext_dirty(handle_t
*handle
, struct inode
*inode
,
134 struct ext4_ext_path
*path
)
138 /* path points to block */
139 err
= ext4_handle_dirty_metadata(handle
, inode
, path
->p_bh
);
141 /* path points to leaf/index in inode body */
142 err
= ext4_mark_inode_dirty(handle
, inode
);
147 static ext4_fsblk_t
ext4_ext_find_goal(struct inode
*inode
,
148 struct ext4_ext_path
*path
,
151 struct ext4_inode_info
*ei
= EXT4_I(inode
);
152 ext4_fsblk_t bg_start
;
153 ext4_fsblk_t last_block
;
154 ext4_grpblk_t colour
;
155 ext4_group_t block_group
;
156 int flex_size
= ext4_flex_bg_size(EXT4_SB(inode
->i_sb
));
160 struct ext4_extent
*ex
;
161 depth
= path
->p_depth
;
163 /* try to predict block placement */
164 ex
= path
[depth
].p_ext
;
166 return ext_pblock(ex
)+(block
-le32_to_cpu(ex
->ee_block
));
168 /* it looks like index is empty;
169 * try to find starting block from index itself */
170 if (path
[depth
].p_bh
)
171 return path
[depth
].p_bh
->b_blocknr
;
174 /* OK. use inode's group */
175 block_group
= ei
->i_block_group
;
176 if (flex_size
>= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
) {
178 * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
179 * block groups per flexgroup, reserve the first block
180 * group for directories and special files. Regular
181 * files will start at the second block group. This
182 * tends to speed up directory access and improves
185 block_group
&= ~(flex_size
-1);
186 if (S_ISREG(inode
->i_mode
))
189 bg_start
= (block_group
* EXT4_BLOCKS_PER_GROUP(inode
->i_sb
)) +
190 le32_to_cpu(EXT4_SB(inode
->i_sb
)->s_es
->s_first_data_block
);
191 last_block
= ext4_blocks_count(EXT4_SB(inode
->i_sb
)->s_es
) - 1;
194 * If we are doing delayed allocation, we don't need take
195 * colour into account.
197 if (test_opt(inode
->i_sb
, DELALLOC
))
200 if (bg_start
+ EXT4_BLOCKS_PER_GROUP(inode
->i_sb
) <= last_block
)
201 colour
= (current
->pid
% 16) *
202 (EXT4_BLOCKS_PER_GROUP(inode
->i_sb
) / 16);
204 colour
= (current
->pid
% 16) * ((last_block
- bg_start
) / 16);
205 return bg_start
+ colour
+ block
;
209 * Allocation for a meta data block
212 ext4_ext_new_meta_block(handle_t
*handle
, struct inode
*inode
,
213 struct ext4_ext_path
*path
,
214 struct ext4_extent
*ex
, int *err
)
216 ext4_fsblk_t goal
, newblock
;
218 goal
= ext4_ext_find_goal(inode
, path
, le32_to_cpu(ex
->ee_block
));
219 newblock
= ext4_new_meta_blocks(handle
, inode
, goal
, NULL
, err
);
223 static int ext4_ext_space_block(struct inode
*inode
)
227 size
= (inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
228 / sizeof(struct ext4_extent
);
229 #ifdef AGGRESSIVE_TEST
236 static int ext4_ext_space_block_idx(struct inode
*inode
)
240 size
= (inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
241 / sizeof(struct ext4_extent_idx
);
242 #ifdef AGGRESSIVE_TEST
249 static int ext4_ext_space_root(struct inode
*inode
)
253 size
= sizeof(EXT4_I(inode
)->i_data
);
254 size
-= sizeof(struct ext4_extent_header
);
255 size
/= sizeof(struct ext4_extent
);
256 #ifdef AGGRESSIVE_TEST
263 static int ext4_ext_space_root_idx(struct inode
*inode
)
267 size
= sizeof(EXT4_I(inode
)->i_data
);
268 size
-= sizeof(struct ext4_extent_header
);
269 size
/= sizeof(struct ext4_extent_idx
);
270 #ifdef AGGRESSIVE_TEST
278 * Calculate the number of metadata blocks needed
279 * to allocate @blocks
280 * Worse case is one block per extent
282 int ext4_ext_calc_metadata_amount(struct inode
*inode
, int blocks
)
284 int lcap
, icap
, rcap
, leafs
, idxs
, num
;
285 int newextents
= blocks
;
287 rcap
= ext4_ext_space_root_idx(inode
);
288 lcap
= ext4_ext_space_block(inode
);
289 icap
= ext4_ext_space_block_idx(inode
);
291 /* number of new leaf blocks needed */
292 num
= leafs
= (newextents
+ lcap
- 1) / lcap
;
295 * Worse case, we need separate index block(s)
296 * to link all new leaf blocks
298 idxs
= (leafs
+ icap
- 1) / icap
;
301 idxs
= (idxs
+ icap
- 1) / icap
;
302 } while (idxs
> rcap
);
308 ext4_ext_max_entries(struct inode
*inode
, int depth
)
312 if (depth
== ext_depth(inode
)) {
314 max
= ext4_ext_space_root(inode
);
316 max
= ext4_ext_space_root_idx(inode
);
319 max
= ext4_ext_space_block(inode
);
321 max
= ext4_ext_space_block_idx(inode
);
327 static int ext4_valid_extent(struct inode
*inode
, struct ext4_extent
*ext
)
329 ext4_fsblk_t block
= ext_pblock(ext
);
330 int len
= ext4_ext_get_actual_len(ext
);
332 return ext4_data_block_valid(EXT4_SB(inode
->i_sb
), block
, len
);
335 static int ext4_valid_extent_idx(struct inode
*inode
,
336 struct ext4_extent_idx
*ext_idx
)
338 ext4_fsblk_t block
= idx_pblock(ext_idx
);
340 return ext4_data_block_valid(EXT4_SB(inode
->i_sb
), block
, 1);
343 static int ext4_valid_extent_entries(struct inode
*inode
,
344 struct ext4_extent_header
*eh
,
347 struct ext4_extent
*ext
;
348 struct ext4_extent_idx
*ext_idx
;
349 unsigned short entries
;
350 if (eh
->eh_entries
== 0)
353 entries
= le16_to_cpu(eh
->eh_entries
);
357 ext
= EXT_FIRST_EXTENT(eh
);
359 if (!ext4_valid_extent(inode
, ext
))
365 ext_idx
= EXT_FIRST_INDEX(eh
);
367 if (!ext4_valid_extent_idx(inode
, ext_idx
))
376 static int __ext4_ext_check(const char *function
, struct inode
*inode
,
377 struct ext4_extent_header
*eh
,
380 const char *error_msg
;
383 if (unlikely(eh
->eh_magic
!= EXT4_EXT_MAGIC
)) {
384 error_msg
= "invalid magic";
387 if (unlikely(le16_to_cpu(eh
->eh_depth
) != depth
)) {
388 error_msg
= "unexpected eh_depth";
391 if (unlikely(eh
->eh_max
== 0)) {
392 error_msg
= "invalid eh_max";
395 max
= ext4_ext_max_entries(inode
, depth
);
396 if (unlikely(le16_to_cpu(eh
->eh_max
) > max
)) {
397 error_msg
= "too large eh_max";
400 if (unlikely(le16_to_cpu(eh
->eh_entries
) > le16_to_cpu(eh
->eh_max
))) {
401 error_msg
= "invalid eh_entries";
404 if (!ext4_valid_extent_entries(inode
, eh
, depth
)) {
405 error_msg
= "invalid extent entries";
411 ext4_error(inode
->i_sb
, function
,
412 "bad header/extent in inode #%lu: %s - magic %x, "
413 "entries %u, max %u(%u), depth %u(%u)",
414 inode
->i_ino
, error_msg
, le16_to_cpu(eh
->eh_magic
),
415 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
),
416 max
, le16_to_cpu(eh
->eh_depth
), depth
);
421 #define ext4_ext_check(inode, eh, depth) \
422 __ext4_ext_check(__func__, inode, eh, depth)
424 int ext4_ext_check_inode(struct inode
*inode
)
426 return ext4_ext_check(inode
, ext_inode_hdr(inode
), ext_depth(inode
));
430 static void ext4_ext_show_path(struct inode
*inode
, struct ext4_ext_path
*path
)
432 int k
, l
= path
->p_depth
;
435 for (k
= 0; k
<= l
; k
++, path
++) {
437 ext_debug(" %d->%llu", le32_to_cpu(path
->p_idx
->ei_block
),
438 idx_pblock(path
->p_idx
));
439 } else if (path
->p_ext
) {
440 ext_debug(" %d:%d:%llu ",
441 le32_to_cpu(path
->p_ext
->ee_block
),
442 ext4_ext_get_actual_len(path
->p_ext
),
443 ext_pblock(path
->p_ext
));
450 static void ext4_ext_show_leaf(struct inode
*inode
, struct ext4_ext_path
*path
)
452 int depth
= ext_depth(inode
);
453 struct ext4_extent_header
*eh
;
454 struct ext4_extent
*ex
;
460 eh
= path
[depth
].p_hdr
;
461 ex
= EXT_FIRST_EXTENT(eh
);
463 for (i
= 0; i
< le16_to_cpu(eh
->eh_entries
); i
++, ex
++) {
464 ext_debug("%d:%d:%llu ", le32_to_cpu(ex
->ee_block
),
465 ext4_ext_get_actual_len(ex
), ext_pblock(ex
));
470 #define ext4_ext_show_path(inode, path)
471 #define ext4_ext_show_leaf(inode, path)
474 void ext4_ext_drop_refs(struct ext4_ext_path
*path
)
476 int depth
= path
->p_depth
;
479 for (i
= 0; i
<= depth
; i
++, path
++)
487 * ext4_ext_binsearch_idx:
488 * binary search for the closest index of the given block
489 * the header must be checked before calling this
492 ext4_ext_binsearch_idx(struct inode
*inode
,
493 struct ext4_ext_path
*path
, ext4_lblk_t block
)
495 struct ext4_extent_header
*eh
= path
->p_hdr
;
496 struct ext4_extent_idx
*r
, *l
, *m
;
499 ext_debug("binsearch for %u(idx): ", block
);
501 l
= EXT_FIRST_INDEX(eh
) + 1;
502 r
= EXT_LAST_INDEX(eh
);
505 if (block
< le32_to_cpu(m
->ei_block
))
509 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ei_block
),
510 m
, le32_to_cpu(m
->ei_block
),
511 r
, le32_to_cpu(r
->ei_block
));
515 ext_debug(" -> %d->%lld ", le32_to_cpu(path
->p_idx
->ei_block
),
516 idx_pblock(path
->p_idx
));
518 #ifdef CHECK_BINSEARCH
520 struct ext4_extent_idx
*chix
, *ix
;
523 chix
= ix
= EXT_FIRST_INDEX(eh
);
524 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ix
++) {
526 le32_to_cpu(ix
->ei_block
) <= le32_to_cpu(ix
[-1].ei_block
)) {
527 printk(KERN_DEBUG
"k=%d, ix=0x%p, "
529 ix
, EXT_FIRST_INDEX(eh
));
530 printk(KERN_DEBUG
"%u <= %u\n",
531 le32_to_cpu(ix
->ei_block
),
532 le32_to_cpu(ix
[-1].ei_block
));
534 BUG_ON(k
&& le32_to_cpu(ix
->ei_block
)
535 <= le32_to_cpu(ix
[-1].ei_block
));
536 if (block
< le32_to_cpu(ix
->ei_block
))
540 BUG_ON(chix
!= path
->p_idx
);
547 * ext4_ext_binsearch:
548 * binary search for closest extent of the given block
549 * the header must be checked before calling this
552 ext4_ext_binsearch(struct inode
*inode
,
553 struct ext4_ext_path
*path
, ext4_lblk_t block
)
555 struct ext4_extent_header
*eh
= path
->p_hdr
;
556 struct ext4_extent
*r
, *l
, *m
;
558 if (eh
->eh_entries
== 0) {
560 * this leaf is empty:
561 * we get such a leaf in split/add case
566 ext_debug("binsearch for %u: ", block
);
568 l
= EXT_FIRST_EXTENT(eh
) + 1;
569 r
= EXT_LAST_EXTENT(eh
);
573 if (block
< le32_to_cpu(m
->ee_block
))
577 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ee_block
),
578 m
, le32_to_cpu(m
->ee_block
),
579 r
, le32_to_cpu(r
->ee_block
));
583 ext_debug(" -> %d:%llu:%d ",
584 le32_to_cpu(path
->p_ext
->ee_block
),
585 ext_pblock(path
->p_ext
),
586 ext4_ext_get_actual_len(path
->p_ext
));
588 #ifdef CHECK_BINSEARCH
590 struct ext4_extent
*chex
, *ex
;
593 chex
= ex
= EXT_FIRST_EXTENT(eh
);
594 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ex
++) {
595 BUG_ON(k
&& le32_to_cpu(ex
->ee_block
)
596 <= le32_to_cpu(ex
[-1].ee_block
));
597 if (block
< le32_to_cpu(ex
->ee_block
))
601 BUG_ON(chex
!= path
->p_ext
);
607 int ext4_ext_tree_init(handle_t
*handle
, struct inode
*inode
)
609 struct ext4_extent_header
*eh
;
611 eh
= ext_inode_hdr(inode
);
614 eh
->eh_magic
= EXT4_EXT_MAGIC
;
615 eh
->eh_max
= cpu_to_le16(ext4_ext_space_root(inode
));
616 ext4_mark_inode_dirty(handle
, inode
);
617 ext4_ext_invalidate_cache(inode
);
621 struct ext4_ext_path
*
622 ext4_ext_find_extent(struct inode
*inode
, ext4_lblk_t block
,
623 struct ext4_ext_path
*path
)
625 struct ext4_extent_header
*eh
;
626 struct buffer_head
*bh
;
627 short int depth
, i
, ppos
= 0, alloc
= 0;
629 eh
= ext_inode_hdr(inode
);
630 depth
= ext_depth(inode
);
632 /* account possible depth increase */
634 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 2),
637 return ERR_PTR(-ENOMEM
);
644 /* walk through the tree */
646 int need_to_validate
= 0;
648 ext_debug("depth %d: num %d, max %d\n",
649 ppos
, le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
651 ext4_ext_binsearch_idx(inode
, path
+ ppos
, block
);
652 path
[ppos
].p_block
= idx_pblock(path
[ppos
].p_idx
);
653 path
[ppos
].p_depth
= i
;
654 path
[ppos
].p_ext
= NULL
;
656 bh
= sb_getblk(inode
->i_sb
, path
[ppos
].p_block
);
659 if (!bh_uptodate_or_lock(bh
)) {
660 if (bh_submit_read(bh
) < 0) {
664 /* validate the extent entries */
665 need_to_validate
= 1;
667 eh
= ext_block_hdr(bh
);
669 BUG_ON(ppos
> depth
);
670 path
[ppos
].p_bh
= bh
;
671 path
[ppos
].p_hdr
= eh
;
674 if (need_to_validate
&& ext4_ext_check(inode
, eh
, i
))
678 path
[ppos
].p_depth
= i
;
679 path
[ppos
].p_ext
= NULL
;
680 path
[ppos
].p_idx
= NULL
;
683 ext4_ext_binsearch(inode
, path
+ ppos
, block
);
684 /* if not an empty leaf */
685 if (path
[ppos
].p_ext
)
686 path
[ppos
].p_block
= ext_pblock(path
[ppos
].p_ext
);
688 ext4_ext_show_path(inode
, path
);
693 ext4_ext_drop_refs(path
);
696 return ERR_PTR(-EIO
);
700 * ext4_ext_insert_index:
701 * insert new index [@logical;@ptr] into the block at @curp;
702 * check where to insert: before @curp or after @curp
704 static int ext4_ext_insert_index(handle_t
*handle
, struct inode
*inode
,
705 struct ext4_ext_path
*curp
,
706 int logical
, ext4_fsblk_t ptr
)
708 struct ext4_extent_idx
*ix
;
711 err
= ext4_ext_get_access(handle
, inode
, curp
);
715 BUG_ON(logical
== le32_to_cpu(curp
->p_idx
->ei_block
));
716 len
= EXT_MAX_INDEX(curp
->p_hdr
) - curp
->p_idx
;
717 if (logical
> le32_to_cpu(curp
->p_idx
->ei_block
)) {
719 if (curp
->p_idx
!= EXT_LAST_INDEX(curp
->p_hdr
)) {
720 len
= (len
- 1) * sizeof(struct ext4_extent_idx
);
721 len
= len
< 0 ? 0 : len
;
722 ext_debug("insert new index %d after: %llu. "
723 "move %d from 0x%p to 0x%p\n",
725 (curp
->p_idx
+ 1), (curp
->p_idx
+ 2));
726 memmove(curp
->p_idx
+ 2, curp
->p_idx
+ 1, len
);
728 ix
= curp
->p_idx
+ 1;
731 len
= len
* sizeof(struct ext4_extent_idx
);
732 len
= len
< 0 ? 0 : len
;
733 ext_debug("insert new index %d before: %llu. "
734 "move %d from 0x%p to 0x%p\n",
736 curp
->p_idx
, (curp
->p_idx
+ 1));
737 memmove(curp
->p_idx
+ 1, curp
->p_idx
, len
);
741 ix
->ei_block
= cpu_to_le32(logical
);
742 ext4_idx_store_pblock(ix
, ptr
);
743 le16_add_cpu(&curp
->p_hdr
->eh_entries
, 1);
745 BUG_ON(le16_to_cpu(curp
->p_hdr
->eh_entries
)
746 > le16_to_cpu(curp
->p_hdr
->eh_max
));
747 BUG_ON(ix
> EXT_LAST_INDEX(curp
->p_hdr
));
749 err
= ext4_ext_dirty(handle
, inode
, curp
);
750 ext4_std_error(inode
->i_sb
, err
);
757 * inserts new subtree into the path, using free index entry
759 * - allocates all needed blocks (new leaf and all intermediate index blocks)
760 * - makes decision where to split
761 * - moves remaining extents and index entries (right to the split point)
762 * into the newly allocated blocks
763 * - initializes subtree
765 static int ext4_ext_split(handle_t
*handle
, struct inode
*inode
,
766 struct ext4_ext_path
*path
,
767 struct ext4_extent
*newext
, int at
)
769 struct buffer_head
*bh
= NULL
;
770 int depth
= ext_depth(inode
);
771 struct ext4_extent_header
*neh
;
772 struct ext4_extent_idx
*fidx
;
773 struct ext4_extent
*ex
;
775 ext4_fsblk_t newblock
, oldblock
;
777 ext4_fsblk_t
*ablocks
= NULL
; /* array of allocated blocks */
780 /* make decision: where to split? */
781 /* FIXME: now decision is simplest: at current extent */
783 /* if current leaf will be split, then we should use
784 * border from split point */
785 BUG_ON(path
[depth
].p_ext
> EXT_MAX_EXTENT(path
[depth
].p_hdr
));
786 if (path
[depth
].p_ext
!= EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
787 border
= path
[depth
].p_ext
[1].ee_block
;
788 ext_debug("leaf will be split."
789 " next leaf starts at %d\n",
790 le32_to_cpu(border
));
792 border
= newext
->ee_block
;
793 ext_debug("leaf will be added."
794 " next leaf starts at %d\n",
795 le32_to_cpu(border
));
799 * If error occurs, then we break processing
800 * and mark filesystem read-only. index won't
801 * be inserted and tree will be in consistent
802 * state. Next mount will repair buffers too.
806 * Get array to track all allocated blocks.
807 * We need this to handle errors and free blocks
810 ablocks
= kzalloc(sizeof(ext4_fsblk_t
) * depth
, GFP_NOFS
);
814 /* allocate all needed blocks */
815 ext_debug("allocate %d blocks for indexes/leaf\n", depth
- at
);
816 for (a
= 0; a
< depth
- at
; a
++) {
817 newblock
= ext4_ext_new_meta_block(handle
, inode
, path
,
821 ablocks
[a
] = newblock
;
824 /* initialize new leaf */
825 newblock
= ablocks
[--a
];
826 BUG_ON(newblock
== 0);
827 bh
= sb_getblk(inode
->i_sb
, newblock
);
834 err
= ext4_journal_get_create_access(handle
, bh
);
838 neh
= ext_block_hdr(bh
);
840 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
));
841 neh
->eh_magic
= EXT4_EXT_MAGIC
;
843 ex
= EXT_FIRST_EXTENT(neh
);
845 /* move remainder of path[depth] to the new leaf */
846 BUG_ON(path
[depth
].p_hdr
->eh_entries
!= path
[depth
].p_hdr
->eh_max
);
847 /* start copy from next extent */
848 /* TODO: we could do it by single memmove */
851 while (path
[depth
].p_ext
<=
852 EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
853 ext_debug("move %d:%llu:%d in new leaf %llu\n",
854 le32_to_cpu(path
[depth
].p_ext
->ee_block
),
855 ext_pblock(path
[depth
].p_ext
),
856 ext4_ext_get_actual_len(path
[depth
].p_ext
),
858 /*memmove(ex++, path[depth].p_ext++,
859 sizeof(struct ext4_extent));
865 memmove(ex
, path
[depth
].p_ext
-m
, sizeof(struct ext4_extent
)*m
);
866 le16_add_cpu(&neh
->eh_entries
, m
);
869 set_buffer_uptodate(bh
);
872 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
878 /* correct old leaf */
880 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
883 le16_add_cpu(&path
[depth
].p_hdr
->eh_entries
, -m
);
884 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
890 /* create intermediate indexes */
894 ext_debug("create %d intermediate indices\n", k
);
895 /* insert new index into current index block */
896 /* current depth stored in i var */
900 newblock
= ablocks
[--a
];
901 bh
= sb_getblk(inode
->i_sb
, newblock
);
908 err
= ext4_journal_get_create_access(handle
, bh
);
912 neh
= ext_block_hdr(bh
);
913 neh
->eh_entries
= cpu_to_le16(1);
914 neh
->eh_magic
= EXT4_EXT_MAGIC
;
915 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
));
916 neh
->eh_depth
= cpu_to_le16(depth
- i
);
917 fidx
= EXT_FIRST_INDEX(neh
);
918 fidx
->ei_block
= border
;
919 ext4_idx_store_pblock(fidx
, oldblock
);
921 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
922 i
, newblock
, le32_to_cpu(border
), oldblock
);
927 ext_debug("cur 0x%p, last 0x%p\n", path
[i
].p_idx
,
928 EXT_MAX_INDEX(path
[i
].p_hdr
));
929 BUG_ON(EXT_MAX_INDEX(path
[i
].p_hdr
) !=
930 EXT_LAST_INDEX(path
[i
].p_hdr
));
931 while (path
[i
].p_idx
<= EXT_MAX_INDEX(path
[i
].p_hdr
)) {
932 ext_debug("%d: move %d:%llu in new index %llu\n", i
,
933 le32_to_cpu(path
[i
].p_idx
->ei_block
),
934 idx_pblock(path
[i
].p_idx
),
936 /*memmove(++fidx, path[i].p_idx++,
937 sizeof(struct ext4_extent_idx));
939 BUG_ON(neh->eh_entries > neh->eh_max);*/
944 memmove(++fidx
, path
[i
].p_idx
- m
,
945 sizeof(struct ext4_extent_idx
) * m
);
946 le16_add_cpu(&neh
->eh_entries
, m
);
948 set_buffer_uptodate(bh
);
951 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
957 /* correct old index */
959 err
= ext4_ext_get_access(handle
, inode
, path
+ i
);
962 le16_add_cpu(&path
[i
].p_hdr
->eh_entries
, -m
);
963 err
= ext4_ext_dirty(handle
, inode
, path
+ i
);
971 /* insert new index */
972 err
= ext4_ext_insert_index(handle
, inode
, path
+ at
,
973 le32_to_cpu(border
), newblock
);
977 if (buffer_locked(bh
))
983 /* free all allocated blocks in error case */
984 for (i
= 0; i
< depth
; i
++) {
987 ext4_free_blocks(handle
, inode
, ablocks
[i
], 1, 1);
996 * ext4_ext_grow_indepth:
997 * implements tree growing procedure:
998 * - allocates new block
999 * - moves top-level data (index block or leaf) into the new block
1000 * - initializes new top-level, creating index that points to the
1001 * just created block
1003 static int ext4_ext_grow_indepth(handle_t
*handle
, struct inode
*inode
,
1004 struct ext4_ext_path
*path
,
1005 struct ext4_extent
*newext
)
1007 struct ext4_ext_path
*curp
= path
;
1008 struct ext4_extent_header
*neh
;
1009 struct ext4_extent_idx
*fidx
;
1010 struct buffer_head
*bh
;
1011 ext4_fsblk_t newblock
;
1014 newblock
= ext4_ext_new_meta_block(handle
, inode
, path
, newext
, &err
);
1018 bh
= sb_getblk(inode
->i_sb
, newblock
);
1021 ext4_std_error(inode
->i_sb
, err
);
1026 err
= ext4_journal_get_create_access(handle
, bh
);
1032 /* move top-level index/leaf into new block */
1033 memmove(bh
->b_data
, curp
->p_hdr
, sizeof(EXT4_I(inode
)->i_data
));
1035 /* set size of new block */
1036 neh
= ext_block_hdr(bh
);
1037 /* old root could have indexes or leaves
1038 * so calculate e_max right way */
1039 if (ext_depth(inode
))
1040 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
));
1042 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
));
1043 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1044 set_buffer_uptodate(bh
);
1047 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1051 /* create index in new top-level index: num,max,pointer */
1052 err
= ext4_ext_get_access(handle
, inode
, curp
);
1056 curp
->p_hdr
->eh_magic
= EXT4_EXT_MAGIC
;
1057 curp
->p_hdr
->eh_max
= cpu_to_le16(ext4_ext_space_root_idx(inode
));
1058 curp
->p_hdr
->eh_entries
= cpu_to_le16(1);
1059 curp
->p_idx
= EXT_FIRST_INDEX(curp
->p_hdr
);
1061 if (path
[0].p_hdr
->eh_depth
)
1062 curp
->p_idx
->ei_block
=
1063 EXT_FIRST_INDEX(path
[0].p_hdr
)->ei_block
;
1065 curp
->p_idx
->ei_block
=
1066 EXT_FIRST_EXTENT(path
[0].p_hdr
)->ee_block
;
1067 ext4_idx_store_pblock(curp
->p_idx
, newblock
);
1069 neh
= ext_inode_hdr(inode
);
1070 fidx
= EXT_FIRST_INDEX(neh
);
1071 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1072 le16_to_cpu(neh
->eh_entries
), le16_to_cpu(neh
->eh_max
),
1073 le32_to_cpu(fidx
->ei_block
), idx_pblock(fidx
));
1075 neh
->eh_depth
= cpu_to_le16(path
->p_depth
+ 1);
1076 err
= ext4_ext_dirty(handle
, inode
, curp
);
1084 * ext4_ext_create_new_leaf:
1085 * finds empty index and adds new leaf.
1086 * if no free index is found, then it requests in-depth growing.
1088 static int ext4_ext_create_new_leaf(handle_t
*handle
, struct inode
*inode
,
1089 struct ext4_ext_path
*path
,
1090 struct ext4_extent
*newext
)
1092 struct ext4_ext_path
*curp
;
1093 int depth
, i
, err
= 0;
1096 i
= depth
= ext_depth(inode
);
1098 /* walk up to the tree and look for free index entry */
1099 curp
= path
+ depth
;
1100 while (i
> 0 && !EXT_HAS_FREE_INDEX(curp
)) {
1105 /* we use already allocated block for index block,
1106 * so subsequent data blocks should be contiguous */
1107 if (EXT_HAS_FREE_INDEX(curp
)) {
1108 /* if we found index with free entry, then use that
1109 * entry: create all needed subtree and add new leaf */
1110 err
= ext4_ext_split(handle
, inode
, path
, newext
, i
);
1115 ext4_ext_drop_refs(path
);
1116 path
= ext4_ext_find_extent(inode
,
1117 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1120 err
= PTR_ERR(path
);
1122 /* tree is full, time to grow in depth */
1123 err
= ext4_ext_grow_indepth(handle
, inode
, path
, newext
);
1128 ext4_ext_drop_refs(path
);
1129 path
= ext4_ext_find_extent(inode
,
1130 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1133 err
= PTR_ERR(path
);
1138 * only first (depth 0 -> 1) produces free space;
1139 * in all other cases we have to split the grown tree
1141 depth
= ext_depth(inode
);
1142 if (path
[depth
].p_hdr
->eh_entries
== path
[depth
].p_hdr
->eh_max
) {
1143 /* now we need to split */
1153 * search the closest allocated block to the left for *logical
1154 * and returns it at @logical + it's physical address at @phys
1155 * if *logical is the smallest allocated block, the function
1156 * returns 0 at @phys
1157 * return value contains 0 (success) or error code
1160 ext4_ext_search_left(struct inode
*inode
, struct ext4_ext_path
*path
,
1161 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
)
1163 struct ext4_extent_idx
*ix
;
1164 struct ext4_extent
*ex
;
1167 BUG_ON(path
== NULL
);
1168 depth
= path
->p_depth
;
1171 if (depth
== 0 && path
->p_ext
== NULL
)
1174 /* usually extent in the path covers blocks smaller
1175 * then *logical, but it can be that extent is the
1176 * first one in the file */
1178 ex
= path
[depth
].p_ext
;
1179 ee_len
= ext4_ext_get_actual_len(ex
);
1180 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1181 BUG_ON(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
);
1182 while (--depth
>= 0) {
1183 ix
= path
[depth
].p_idx
;
1184 BUG_ON(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
));
1189 BUG_ON(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
));
1191 *logical
= le32_to_cpu(ex
->ee_block
) + ee_len
- 1;
1192 *phys
= ext_pblock(ex
) + ee_len
- 1;
1197 * search the closest allocated block to the right for *logical
1198 * and returns it at @logical + it's physical address at @phys
1199 * if *logical is the smallest allocated block, the function
1200 * returns 0 at @phys
1201 * return value contains 0 (success) or error code
1204 ext4_ext_search_right(struct inode
*inode
, struct ext4_ext_path
*path
,
1205 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
)
1207 struct buffer_head
*bh
= NULL
;
1208 struct ext4_extent_header
*eh
;
1209 struct ext4_extent_idx
*ix
;
1210 struct ext4_extent
*ex
;
1212 int depth
; /* Note, NOT eh_depth; depth from top of tree */
1215 BUG_ON(path
== NULL
);
1216 depth
= path
->p_depth
;
1219 if (depth
== 0 && path
->p_ext
== NULL
)
1222 /* usually extent in the path covers blocks smaller
1223 * then *logical, but it can be that extent is the
1224 * first one in the file */
1226 ex
= path
[depth
].p_ext
;
1227 ee_len
= ext4_ext_get_actual_len(ex
);
1228 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1229 BUG_ON(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
);
1230 while (--depth
>= 0) {
1231 ix
= path
[depth
].p_idx
;
1232 BUG_ON(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
));
1234 *logical
= le32_to_cpu(ex
->ee_block
);
1235 *phys
= ext_pblock(ex
);
1239 BUG_ON(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
));
1241 if (ex
!= EXT_LAST_EXTENT(path
[depth
].p_hdr
)) {
1242 /* next allocated block in this leaf */
1244 *logical
= le32_to_cpu(ex
->ee_block
);
1245 *phys
= ext_pblock(ex
);
1249 /* go up and search for index to the right */
1250 while (--depth
>= 0) {
1251 ix
= path
[depth
].p_idx
;
1252 if (ix
!= EXT_LAST_INDEX(path
[depth
].p_hdr
))
1256 /* we've gone up to the root and found no index to the right */
1260 /* we've found index to the right, let's
1261 * follow it and find the closest allocated
1262 * block to the right */
1264 block
= idx_pblock(ix
);
1265 while (++depth
< path
->p_depth
) {
1266 bh
= sb_bread(inode
->i_sb
, block
);
1269 eh
= ext_block_hdr(bh
);
1270 /* subtract from p_depth to get proper eh_depth */
1271 if (ext4_ext_check(inode
, eh
, path
->p_depth
- depth
)) {
1275 ix
= EXT_FIRST_INDEX(eh
);
1276 block
= idx_pblock(ix
);
1280 bh
= sb_bread(inode
->i_sb
, block
);
1283 eh
= ext_block_hdr(bh
);
1284 if (ext4_ext_check(inode
, eh
, path
->p_depth
- depth
)) {
1288 ex
= EXT_FIRST_EXTENT(eh
);
1289 *logical
= le32_to_cpu(ex
->ee_block
);
1290 *phys
= ext_pblock(ex
);
1296 * ext4_ext_next_allocated_block:
1297 * returns allocated block in subsequent extent or EXT_MAX_BLOCK.
1298 * NOTE: it considers block number from index entry as
1299 * allocated block. Thus, index entries have to be consistent
1303 ext4_ext_next_allocated_block(struct ext4_ext_path
*path
)
1307 BUG_ON(path
== NULL
);
1308 depth
= path
->p_depth
;
1310 if (depth
== 0 && path
->p_ext
== NULL
)
1311 return EXT_MAX_BLOCK
;
1313 while (depth
>= 0) {
1314 if (depth
== path
->p_depth
) {
1316 if (path
[depth
].p_ext
!=
1317 EXT_LAST_EXTENT(path
[depth
].p_hdr
))
1318 return le32_to_cpu(path
[depth
].p_ext
[1].ee_block
);
1321 if (path
[depth
].p_idx
!=
1322 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1323 return le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1328 return EXT_MAX_BLOCK
;
1332 * ext4_ext_next_leaf_block:
1333 * returns first allocated block from next leaf or EXT_MAX_BLOCK
1335 static ext4_lblk_t
ext4_ext_next_leaf_block(struct inode
*inode
,
1336 struct ext4_ext_path
*path
)
1340 BUG_ON(path
== NULL
);
1341 depth
= path
->p_depth
;
1343 /* zero-tree has no leaf blocks at all */
1345 return EXT_MAX_BLOCK
;
1347 /* go to index block */
1350 while (depth
>= 0) {
1351 if (path
[depth
].p_idx
!=
1352 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1353 return (ext4_lblk_t
)
1354 le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1358 return EXT_MAX_BLOCK
;
1362 * ext4_ext_correct_indexes:
1363 * if leaf gets modified and modified extent is first in the leaf,
1364 * then we have to correct all indexes above.
1365 * TODO: do we need to correct tree in all cases?
1367 static int ext4_ext_correct_indexes(handle_t
*handle
, struct inode
*inode
,
1368 struct ext4_ext_path
*path
)
1370 struct ext4_extent_header
*eh
;
1371 int depth
= ext_depth(inode
);
1372 struct ext4_extent
*ex
;
1376 eh
= path
[depth
].p_hdr
;
1377 ex
= path
[depth
].p_ext
;
1382 /* there is no tree at all */
1386 if (ex
!= EXT_FIRST_EXTENT(eh
)) {
1387 /* we correct tree if first leaf got modified only */
1392 * TODO: we need correction if border is smaller than current one
1395 border
= path
[depth
].p_ext
->ee_block
;
1396 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1399 path
[k
].p_idx
->ei_block
= border
;
1400 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1405 /* change all left-side indexes */
1406 if (path
[k
+1].p_idx
!= EXT_FIRST_INDEX(path
[k
+1].p_hdr
))
1408 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1411 path
[k
].p_idx
->ei_block
= border
;
1412 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1421 ext4_can_extents_be_merged(struct inode
*inode
, struct ext4_extent
*ex1
,
1422 struct ext4_extent
*ex2
)
1424 unsigned short ext1_ee_len
, ext2_ee_len
, max_len
;
1427 * Make sure that either both extents are uninitialized, or
1430 if (ext4_ext_is_uninitialized(ex1
) ^ ext4_ext_is_uninitialized(ex2
))
1433 if (ext4_ext_is_uninitialized(ex1
))
1434 max_len
= EXT_UNINIT_MAX_LEN
;
1436 max_len
= EXT_INIT_MAX_LEN
;
1438 ext1_ee_len
= ext4_ext_get_actual_len(ex1
);
1439 ext2_ee_len
= ext4_ext_get_actual_len(ex2
);
1441 if (le32_to_cpu(ex1
->ee_block
) + ext1_ee_len
!=
1442 le32_to_cpu(ex2
->ee_block
))
1446 * To allow future support for preallocated extents to be added
1447 * as an RO_COMPAT feature, refuse to merge to extents if
1448 * this can result in the top bit of ee_len being set.
1450 if (ext1_ee_len
+ ext2_ee_len
> max_len
)
1452 #ifdef AGGRESSIVE_TEST
1453 if (ext1_ee_len
>= 4)
1457 if (ext_pblock(ex1
) + ext1_ee_len
== ext_pblock(ex2
))
1463 * This function tries to merge the "ex" extent to the next extent in the tree.
1464 * It always tries to merge towards right. If you want to merge towards
1465 * left, pass "ex - 1" as argument instead of "ex".
1466 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1467 * 1 if they got merged.
1469 int ext4_ext_try_to_merge(struct inode
*inode
,
1470 struct ext4_ext_path
*path
,
1471 struct ext4_extent
*ex
)
1473 struct ext4_extent_header
*eh
;
1474 unsigned int depth
, len
;
1476 int uninitialized
= 0;
1478 depth
= ext_depth(inode
);
1479 BUG_ON(path
[depth
].p_hdr
== NULL
);
1480 eh
= path
[depth
].p_hdr
;
1482 while (ex
< EXT_LAST_EXTENT(eh
)) {
1483 if (!ext4_can_extents_be_merged(inode
, ex
, ex
+ 1))
1485 /* merge with next extent! */
1486 if (ext4_ext_is_uninitialized(ex
))
1488 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1489 + ext4_ext_get_actual_len(ex
+ 1));
1491 ext4_ext_mark_uninitialized(ex
);
1493 if (ex
+ 1 < EXT_LAST_EXTENT(eh
)) {
1494 len
= (EXT_LAST_EXTENT(eh
) - ex
- 1)
1495 * sizeof(struct ext4_extent
);
1496 memmove(ex
+ 1, ex
+ 2, len
);
1498 le16_add_cpu(&eh
->eh_entries
, -1);
1500 WARN_ON(eh
->eh_entries
== 0);
1501 if (!eh
->eh_entries
)
1502 ext4_error(inode
->i_sb
, "ext4_ext_try_to_merge",
1503 "inode#%lu, eh->eh_entries = 0!", inode
->i_ino
);
1510 * check if a portion of the "newext" extent overlaps with an
1513 * If there is an overlap discovered, it updates the length of the newext
1514 * such that there will be no overlap, and then returns 1.
1515 * If there is no overlap found, it returns 0.
1517 unsigned int ext4_ext_check_overlap(struct inode
*inode
,
1518 struct ext4_extent
*newext
,
1519 struct ext4_ext_path
*path
)
1522 unsigned int depth
, len1
;
1523 unsigned int ret
= 0;
1525 b1
= le32_to_cpu(newext
->ee_block
);
1526 len1
= ext4_ext_get_actual_len(newext
);
1527 depth
= ext_depth(inode
);
1528 if (!path
[depth
].p_ext
)
1530 b2
= le32_to_cpu(path
[depth
].p_ext
->ee_block
);
1533 * get the next allocated block if the extent in the path
1534 * is before the requested block(s)
1537 b2
= ext4_ext_next_allocated_block(path
);
1538 if (b2
== EXT_MAX_BLOCK
)
1542 /* check for wrap through zero on extent logical start block*/
1543 if (b1
+ len1
< b1
) {
1544 len1
= EXT_MAX_BLOCK
- b1
;
1545 newext
->ee_len
= cpu_to_le16(len1
);
1549 /* check for overlap */
1550 if (b1
+ len1
> b2
) {
1551 newext
->ee_len
= cpu_to_le16(b2
- b1
);
1559 * ext4_ext_insert_extent:
1560 * tries to merge requsted extent into the existing extent or
1561 * inserts requested extent as new one into the tree,
1562 * creating new leaf in the no-space case.
1564 int ext4_ext_insert_extent(handle_t
*handle
, struct inode
*inode
,
1565 struct ext4_ext_path
*path
,
1566 struct ext4_extent
*newext
)
1568 struct ext4_extent_header
*eh
;
1569 struct ext4_extent
*ex
, *fex
;
1570 struct ext4_extent
*nearex
; /* nearest extent */
1571 struct ext4_ext_path
*npath
= NULL
;
1572 int depth
, len
, err
;
1574 unsigned uninitialized
= 0;
1576 BUG_ON(ext4_ext_get_actual_len(newext
) == 0);
1577 depth
= ext_depth(inode
);
1578 ex
= path
[depth
].p_ext
;
1579 BUG_ON(path
[depth
].p_hdr
== NULL
);
1581 /* try to insert block into found extent and return */
1582 if (ex
&& ext4_can_extents_be_merged(inode
, ex
, newext
)) {
1583 ext_debug("append %d block to %d:%d (from %llu)\n",
1584 ext4_ext_get_actual_len(newext
),
1585 le32_to_cpu(ex
->ee_block
),
1586 ext4_ext_get_actual_len(ex
), ext_pblock(ex
));
1587 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
1592 * ext4_can_extents_be_merged should have checked that either
1593 * both extents are uninitialized, or both aren't. Thus we
1594 * need to check only one of them here.
1596 if (ext4_ext_is_uninitialized(ex
))
1598 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1599 + ext4_ext_get_actual_len(newext
));
1601 ext4_ext_mark_uninitialized(ex
);
1602 eh
= path
[depth
].p_hdr
;
1608 depth
= ext_depth(inode
);
1609 eh
= path
[depth
].p_hdr
;
1610 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
))
1613 /* probably next leaf has space for us? */
1614 fex
= EXT_LAST_EXTENT(eh
);
1615 next
= ext4_ext_next_leaf_block(inode
, path
);
1616 if (le32_to_cpu(newext
->ee_block
) > le32_to_cpu(fex
->ee_block
)
1617 && next
!= EXT_MAX_BLOCK
) {
1618 ext_debug("next leaf block - %d\n", next
);
1619 BUG_ON(npath
!= NULL
);
1620 npath
= ext4_ext_find_extent(inode
, next
, NULL
);
1622 return PTR_ERR(npath
);
1623 BUG_ON(npath
->p_depth
!= path
->p_depth
);
1624 eh
= npath
[depth
].p_hdr
;
1625 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
)) {
1626 ext_debug("next leaf isnt full(%d)\n",
1627 le16_to_cpu(eh
->eh_entries
));
1631 ext_debug("next leaf has no free space(%d,%d)\n",
1632 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
1636 * There is no free space in the found leaf.
1637 * We're gonna add a new leaf in the tree.
1639 err
= ext4_ext_create_new_leaf(handle
, inode
, path
, newext
);
1642 depth
= ext_depth(inode
);
1643 eh
= path
[depth
].p_hdr
;
1646 nearex
= path
[depth
].p_ext
;
1648 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
1653 /* there is no extent in this leaf, create first one */
1654 ext_debug("first extent in the leaf: %d:%llu:%d\n",
1655 le32_to_cpu(newext
->ee_block
),
1657 ext4_ext_get_actual_len(newext
));
1658 path
[depth
].p_ext
= EXT_FIRST_EXTENT(eh
);
1659 } else if (le32_to_cpu(newext
->ee_block
)
1660 > le32_to_cpu(nearex
->ee_block
)) {
1661 /* BUG_ON(newext->ee_block == nearex->ee_block); */
1662 if (nearex
!= EXT_LAST_EXTENT(eh
)) {
1663 len
= EXT_MAX_EXTENT(eh
) - nearex
;
1664 len
= (len
- 1) * sizeof(struct ext4_extent
);
1665 len
= len
< 0 ? 0 : len
;
1666 ext_debug("insert %d:%llu:%d after: nearest 0x%p, "
1667 "move %d from 0x%p to 0x%p\n",
1668 le32_to_cpu(newext
->ee_block
),
1670 ext4_ext_get_actual_len(newext
),
1671 nearex
, len
, nearex
+ 1, nearex
+ 2);
1672 memmove(nearex
+ 2, nearex
+ 1, len
);
1674 path
[depth
].p_ext
= nearex
+ 1;
1676 BUG_ON(newext
->ee_block
== nearex
->ee_block
);
1677 len
= (EXT_MAX_EXTENT(eh
) - nearex
) * sizeof(struct ext4_extent
);
1678 len
= len
< 0 ? 0 : len
;
1679 ext_debug("insert %d:%llu:%d before: nearest 0x%p, "
1680 "move %d from 0x%p to 0x%p\n",
1681 le32_to_cpu(newext
->ee_block
),
1683 ext4_ext_get_actual_len(newext
),
1684 nearex
, len
, nearex
+ 1, nearex
+ 2);
1685 memmove(nearex
+ 1, nearex
, len
);
1686 path
[depth
].p_ext
= nearex
;
1689 le16_add_cpu(&eh
->eh_entries
, 1);
1690 nearex
= path
[depth
].p_ext
;
1691 nearex
->ee_block
= newext
->ee_block
;
1692 ext4_ext_store_pblock(nearex
, ext_pblock(newext
));
1693 nearex
->ee_len
= newext
->ee_len
;
1696 /* try to merge extents to the right */
1697 ext4_ext_try_to_merge(inode
, path
, nearex
);
1699 /* try to merge extents to the left */
1701 /* time to correct all indexes above */
1702 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
1706 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
1710 ext4_ext_drop_refs(npath
);
1713 ext4_ext_invalidate_cache(inode
);
1717 int ext4_ext_walk_space(struct inode
*inode
, ext4_lblk_t block
,
1718 ext4_lblk_t num
, ext_prepare_callback func
,
1721 struct ext4_ext_path
*path
= NULL
;
1722 struct ext4_ext_cache cbex
;
1723 struct ext4_extent
*ex
;
1724 ext4_lblk_t next
, start
= 0, end
= 0;
1725 ext4_lblk_t last
= block
+ num
;
1726 int depth
, exists
, err
= 0;
1728 BUG_ON(func
== NULL
);
1729 BUG_ON(inode
== NULL
);
1731 while (block
< last
&& block
!= EXT_MAX_BLOCK
) {
1733 /* find extent for this block */
1734 path
= ext4_ext_find_extent(inode
, block
, path
);
1736 err
= PTR_ERR(path
);
1741 depth
= ext_depth(inode
);
1742 BUG_ON(path
[depth
].p_hdr
== NULL
);
1743 ex
= path
[depth
].p_ext
;
1744 next
= ext4_ext_next_allocated_block(path
);
1748 /* there is no extent yet, so try to allocate
1749 * all requested space */
1752 } else if (le32_to_cpu(ex
->ee_block
) > block
) {
1753 /* need to allocate space before found extent */
1755 end
= le32_to_cpu(ex
->ee_block
);
1756 if (block
+ num
< end
)
1758 } else if (block
>= le32_to_cpu(ex
->ee_block
)
1759 + ext4_ext_get_actual_len(ex
)) {
1760 /* need to allocate space after found extent */
1765 } else if (block
>= le32_to_cpu(ex
->ee_block
)) {
1767 * some part of requested space is covered
1771 end
= le32_to_cpu(ex
->ee_block
)
1772 + ext4_ext_get_actual_len(ex
);
1773 if (block
+ num
< end
)
1779 BUG_ON(end
<= start
);
1782 cbex
.ec_block
= start
;
1783 cbex
.ec_len
= end
- start
;
1785 cbex
.ec_type
= EXT4_EXT_CACHE_GAP
;
1787 cbex
.ec_block
= le32_to_cpu(ex
->ee_block
);
1788 cbex
.ec_len
= ext4_ext_get_actual_len(ex
);
1789 cbex
.ec_start
= ext_pblock(ex
);
1790 cbex
.ec_type
= EXT4_EXT_CACHE_EXTENT
;
1793 BUG_ON(cbex
.ec_len
== 0);
1794 err
= func(inode
, path
, &cbex
, ex
, cbdata
);
1795 ext4_ext_drop_refs(path
);
1800 if (err
== EXT_REPEAT
)
1802 else if (err
== EXT_BREAK
) {
1807 if (ext_depth(inode
) != depth
) {
1808 /* depth was changed. we have to realloc path */
1813 block
= cbex
.ec_block
+ cbex
.ec_len
;
1817 ext4_ext_drop_refs(path
);
1825 ext4_ext_put_in_cache(struct inode
*inode
, ext4_lblk_t block
,
1826 __u32 len
, ext4_fsblk_t start
, int type
)
1828 struct ext4_ext_cache
*cex
;
1830 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1831 cex
= &EXT4_I(inode
)->i_cached_extent
;
1832 cex
->ec_type
= type
;
1833 cex
->ec_block
= block
;
1835 cex
->ec_start
= start
;
1836 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1840 * ext4_ext_put_gap_in_cache:
1841 * calculate boundaries of the gap that the requested block fits into
1842 * and cache this gap
1845 ext4_ext_put_gap_in_cache(struct inode
*inode
, struct ext4_ext_path
*path
,
1848 int depth
= ext_depth(inode
);
1851 struct ext4_extent
*ex
;
1853 ex
= path
[depth
].p_ext
;
1855 /* there is no extent yet, so gap is [0;-] */
1857 len
= EXT_MAX_BLOCK
;
1858 ext_debug("cache gap(whole file):");
1859 } else if (block
< le32_to_cpu(ex
->ee_block
)) {
1861 len
= le32_to_cpu(ex
->ee_block
) - block
;
1862 ext_debug("cache gap(before): %u [%u:%u]",
1864 le32_to_cpu(ex
->ee_block
),
1865 ext4_ext_get_actual_len(ex
));
1866 } else if (block
>= le32_to_cpu(ex
->ee_block
)
1867 + ext4_ext_get_actual_len(ex
)) {
1869 lblock
= le32_to_cpu(ex
->ee_block
)
1870 + ext4_ext_get_actual_len(ex
);
1872 next
= ext4_ext_next_allocated_block(path
);
1873 ext_debug("cache gap(after): [%u:%u] %u",
1874 le32_to_cpu(ex
->ee_block
),
1875 ext4_ext_get_actual_len(ex
),
1877 BUG_ON(next
== lblock
);
1878 len
= next
- lblock
;
1884 ext_debug(" -> %u:%lu\n", lblock
, len
);
1885 ext4_ext_put_in_cache(inode
, lblock
, len
, 0, EXT4_EXT_CACHE_GAP
);
1889 ext4_ext_in_cache(struct inode
*inode
, ext4_lblk_t block
,
1890 struct ext4_extent
*ex
)
1892 struct ext4_ext_cache
*cex
;
1893 int ret
= EXT4_EXT_CACHE_NO
;
1896 * We borrow i_block_reservation_lock to protect i_cached_extent
1898 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1899 cex
= &EXT4_I(inode
)->i_cached_extent
;
1901 /* has cache valid data? */
1902 if (cex
->ec_type
== EXT4_EXT_CACHE_NO
)
1905 BUG_ON(cex
->ec_type
!= EXT4_EXT_CACHE_GAP
&&
1906 cex
->ec_type
!= EXT4_EXT_CACHE_EXTENT
);
1907 if (block
>= cex
->ec_block
&& block
< cex
->ec_block
+ cex
->ec_len
) {
1908 ex
->ee_block
= cpu_to_le32(cex
->ec_block
);
1909 ext4_ext_store_pblock(ex
, cex
->ec_start
);
1910 ex
->ee_len
= cpu_to_le16(cex
->ec_len
);
1911 ext_debug("%u cached by %u:%u:%llu\n",
1913 cex
->ec_block
, cex
->ec_len
, cex
->ec_start
);
1917 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1923 * removes index from the index block.
1924 * It's used in truncate case only, thus all requests are for
1925 * last index in the block only.
1927 static int ext4_ext_rm_idx(handle_t
*handle
, struct inode
*inode
,
1928 struct ext4_ext_path
*path
)
1930 struct buffer_head
*bh
;
1934 /* free index block */
1936 leaf
= idx_pblock(path
->p_idx
);
1937 BUG_ON(path
->p_hdr
->eh_entries
== 0);
1938 err
= ext4_ext_get_access(handle
, inode
, path
);
1941 le16_add_cpu(&path
->p_hdr
->eh_entries
, -1);
1942 err
= ext4_ext_dirty(handle
, inode
, path
);
1945 ext_debug("index is empty, remove it, free block %llu\n", leaf
);
1946 bh
= sb_find_get_block(inode
->i_sb
, leaf
);
1947 ext4_forget(handle
, 1, inode
, bh
, leaf
);
1948 ext4_free_blocks(handle
, inode
, leaf
, 1, 1);
1953 * ext4_ext_calc_credits_for_single_extent:
1954 * This routine returns max. credits that needed to insert an extent
1955 * to the extent tree.
1956 * When pass the actual path, the caller should calculate credits
1959 int ext4_ext_calc_credits_for_single_extent(struct inode
*inode
, int nrblocks
,
1960 struct ext4_ext_path
*path
)
1963 int depth
= ext_depth(inode
);
1966 /* probably there is space in leaf? */
1967 if (le16_to_cpu(path
[depth
].p_hdr
->eh_entries
)
1968 < le16_to_cpu(path
[depth
].p_hdr
->eh_max
)) {
1971 * There are some space in the leaf tree, no
1972 * need to account for leaf block credit
1974 * bitmaps and block group descriptor blocks
1975 * and other metadat blocks still need to be
1978 /* 1 bitmap, 1 block group descriptor */
1979 ret
= 2 + EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
1983 return ext4_chunk_trans_blocks(inode
, nrblocks
);
1987 * How many index/leaf blocks need to change/allocate to modify nrblocks?
1989 * if nrblocks are fit in a single extent (chunk flag is 1), then
1990 * in the worse case, each tree level index/leaf need to be changed
1991 * if the tree split due to insert a new extent, then the old tree
1992 * index/leaf need to be updated too
1994 * If the nrblocks are discontiguous, they could cause
1995 * the whole tree split more than once, but this is really rare.
1997 int ext4_ext_index_trans_blocks(struct inode
*inode
, int nrblocks
, int chunk
)
2000 int depth
= ext_depth(inode
);
2010 static int ext4_remove_blocks(handle_t
*handle
, struct inode
*inode
,
2011 struct ext4_extent
*ex
,
2012 ext4_lblk_t from
, ext4_lblk_t to
)
2014 struct buffer_head
*bh
;
2015 unsigned short ee_len
= ext4_ext_get_actual_len(ex
);
2016 int i
, metadata
= 0;
2018 if (S_ISDIR(inode
->i_mode
) || S_ISLNK(inode
->i_mode
))
2020 #ifdef EXTENTS_STATS
2022 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2023 spin_lock(&sbi
->s_ext_stats_lock
);
2024 sbi
->s_ext_blocks
+= ee_len
;
2025 sbi
->s_ext_extents
++;
2026 if (ee_len
< sbi
->s_ext_min
)
2027 sbi
->s_ext_min
= ee_len
;
2028 if (ee_len
> sbi
->s_ext_max
)
2029 sbi
->s_ext_max
= ee_len
;
2030 if (ext_depth(inode
) > sbi
->s_depth_max
)
2031 sbi
->s_depth_max
= ext_depth(inode
);
2032 spin_unlock(&sbi
->s_ext_stats_lock
);
2035 if (from
>= le32_to_cpu(ex
->ee_block
)
2036 && to
== le32_to_cpu(ex
->ee_block
) + ee_len
- 1) {
2041 num
= le32_to_cpu(ex
->ee_block
) + ee_len
- from
;
2042 start
= ext_pblock(ex
) + ee_len
- num
;
2043 ext_debug("free last %u blocks starting %llu\n", num
, start
);
2044 for (i
= 0; i
< num
; i
++) {
2045 bh
= sb_find_get_block(inode
->i_sb
, start
+ i
);
2046 ext4_forget(handle
, 0, inode
, bh
, start
+ i
);
2048 ext4_free_blocks(handle
, inode
, start
, num
, metadata
);
2049 } else if (from
== le32_to_cpu(ex
->ee_block
)
2050 && to
<= le32_to_cpu(ex
->ee_block
) + ee_len
- 1) {
2051 printk(KERN_INFO
"strange request: removal %u-%u from %u:%u\n",
2052 from
, to
, le32_to_cpu(ex
->ee_block
), ee_len
);
2054 printk(KERN_INFO
"strange request: removal(2) "
2055 "%u-%u from %u:%u\n",
2056 from
, to
, le32_to_cpu(ex
->ee_block
), ee_len
);
2062 ext4_ext_rm_leaf(handle_t
*handle
, struct inode
*inode
,
2063 struct ext4_ext_path
*path
, ext4_lblk_t start
)
2065 int err
= 0, correct_index
= 0;
2066 int depth
= ext_depth(inode
), credits
;
2067 struct ext4_extent_header
*eh
;
2068 ext4_lblk_t a
, b
, block
;
2070 ext4_lblk_t ex_ee_block
;
2071 unsigned short ex_ee_len
;
2072 unsigned uninitialized
= 0;
2073 struct ext4_extent
*ex
;
2075 /* the header must be checked already in ext4_ext_remove_space() */
2076 ext_debug("truncate since %u in leaf\n", start
);
2077 if (!path
[depth
].p_hdr
)
2078 path
[depth
].p_hdr
= ext_block_hdr(path
[depth
].p_bh
);
2079 eh
= path
[depth
].p_hdr
;
2082 /* find where to start removing */
2083 ex
= EXT_LAST_EXTENT(eh
);
2085 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2086 if (ext4_ext_is_uninitialized(ex
))
2088 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2090 while (ex
>= EXT_FIRST_EXTENT(eh
) &&
2091 ex_ee_block
+ ex_ee_len
> start
) {
2092 ext_debug("remove ext %lu:%u\n", ex_ee_block
, ex_ee_len
);
2093 path
[depth
].p_ext
= ex
;
2095 a
= ex_ee_block
> start
? ex_ee_block
: start
;
2096 b
= ex_ee_block
+ ex_ee_len
- 1 < EXT_MAX_BLOCK
?
2097 ex_ee_block
+ ex_ee_len
- 1 : EXT_MAX_BLOCK
;
2099 ext_debug(" border %u:%u\n", a
, b
);
2101 if (a
!= ex_ee_block
&& b
!= ex_ee_block
+ ex_ee_len
- 1) {
2105 } else if (a
!= ex_ee_block
) {
2106 /* remove tail of the extent */
2107 block
= ex_ee_block
;
2109 } else if (b
!= ex_ee_block
+ ex_ee_len
- 1) {
2110 /* remove head of the extent */
2113 /* there is no "make a hole" API yet */
2116 /* remove whole extent: excellent! */
2117 block
= ex_ee_block
;
2119 BUG_ON(a
!= ex_ee_block
);
2120 BUG_ON(b
!= ex_ee_block
+ ex_ee_len
- 1);
2124 * 3 for leaf, sb, and inode plus 2 (bmap and group
2125 * descriptor) for each block group; assume two block
2126 * groups plus ex_ee_len/blocks_per_block_group for
2129 credits
= 7 + 2*(ex_ee_len
/EXT4_BLOCKS_PER_GROUP(inode
->i_sb
));
2130 if (ex
== EXT_FIRST_EXTENT(eh
)) {
2132 credits
+= (ext_depth(inode
)) + 1;
2134 credits
+= 2 * EXT4_QUOTA_TRANS_BLOCKS(inode
->i_sb
);
2136 err
= ext4_ext_journal_restart(handle
, credits
);
2140 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2144 err
= ext4_remove_blocks(handle
, inode
, ex
, a
, b
);
2149 /* this extent is removed; mark slot entirely unused */
2150 ext4_ext_store_pblock(ex
, 0);
2151 le16_add_cpu(&eh
->eh_entries
, -1);
2154 ex
->ee_block
= cpu_to_le32(block
);
2155 ex
->ee_len
= cpu_to_le16(num
);
2157 * Do not mark uninitialized if all the blocks in the
2158 * extent have been removed.
2160 if (uninitialized
&& num
)
2161 ext4_ext_mark_uninitialized(ex
);
2163 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2167 ext_debug("new extent: %u:%u:%llu\n", block
, num
,
2170 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2171 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2174 if (correct_index
&& eh
->eh_entries
)
2175 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2177 /* if this leaf is free, then we should
2178 * remove it from index block above */
2179 if (err
== 0 && eh
->eh_entries
== 0 && path
[depth
].p_bh
!= NULL
)
2180 err
= ext4_ext_rm_idx(handle
, inode
, path
+ depth
);
2187 * ext4_ext_more_to_rm:
2188 * returns 1 if current index has to be freed (even partial)
2191 ext4_ext_more_to_rm(struct ext4_ext_path
*path
)
2193 BUG_ON(path
->p_idx
== NULL
);
2195 if (path
->p_idx
< EXT_FIRST_INDEX(path
->p_hdr
))
2199 * if truncate on deeper level happened, it wasn't partial,
2200 * so we have to consider current index for truncation
2202 if (le16_to_cpu(path
->p_hdr
->eh_entries
) == path
->p_block
)
2207 static int ext4_ext_remove_space(struct inode
*inode
, ext4_lblk_t start
)
2209 struct super_block
*sb
= inode
->i_sb
;
2210 int depth
= ext_depth(inode
);
2211 struct ext4_ext_path
*path
;
2215 ext_debug("truncate since %u\n", start
);
2217 /* probably first extent we're gonna free will be last in block */
2218 handle
= ext4_journal_start(inode
, depth
+ 1);
2220 return PTR_ERR(handle
);
2222 ext4_ext_invalidate_cache(inode
);
2225 * We start scanning from right side, freeing all the blocks
2226 * after i_size and walking into the tree depth-wise.
2228 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 1), GFP_NOFS
);
2230 ext4_journal_stop(handle
);
2233 path
[0].p_hdr
= ext_inode_hdr(inode
);
2234 if (ext4_ext_check(inode
, path
[0].p_hdr
, depth
)) {
2238 path
[0].p_depth
= depth
;
2240 while (i
>= 0 && err
== 0) {
2242 /* this is leaf block */
2243 err
= ext4_ext_rm_leaf(handle
, inode
, path
, start
);
2244 /* root level has p_bh == NULL, brelse() eats this */
2245 brelse(path
[i
].p_bh
);
2246 path
[i
].p_bh
= NULL
;
2251 /* this is index block */
2252 if (!path
[i
].p_hdr
) {
2253 ext_debug("initialize header\n");
2254 path
[i
].p_hdr
= ext_block_hdr(path
[i
].p_bh
);
2257 if (!path
[i
].p_idx
) {
2258 /* this level hasn't been touched yet */
2259 path
[i
].p_idx
= EXT_LAST_INDEX(path
[i
].p_hdr
);
2260 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
)+1;
2261 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2263 le16_to_cpu(path
[i
].p_hdr
->eh_entries
));
2265 /* we were already here, see at next index */
2269 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2270 i
, EXT_FIRST_INDEX(path
[i
].p_hdr
),
2272 if (ext4_ext_more_to_rm(path
+ i
)) {
2273 struct buffer_head
*bh
;
2274 /* go to the next level */
2275 ext_debug("move to level %d (block %llu)\n",
2276 i
+ 1, idx_pblock(path
[i
].p_idx
));
2277 memset(path
+ i
+ 1, 0, sizeof(*path
));
2278 bh
= sb_bread(sb
, idx_pblock(path
[i
].p_idx
));
2280 /* should we reset i_size? */
2284 if (WARN_ON(i
+ 1 > depth
)) {
2288 if (ext4_ext_check(inode
, ext_block_hdr(bh
),
2293 path
[i
+ 1].p_bh
= bh
;
2295 /* save actual number of indexes since this
2296 * number is changed at the next iteration */
2297 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
);
2300 /* we finished processing this index, go up */
2301 if (path
[i
].p_hdr
->eh_entries
== 0 && i
> 0) {
2302 /* index is empty, remove it;
2303 * handle must be already prepared by the
2304 * truncatei_leaf() */
2305 err
= ext4_ext_rm_idx(handle
, inode
, path
+ i
);
2307 /* root level has p_bh == NULL, brelse() eats this */
2308 brelse(path
[i
].p_bh
);
2309 path
[i
].p_bh
= NULL
;
2311 ext_debug("return to level %d\n", i
);
2315 /* TODO: flexible tree reduction should be here */
2316 if (path
->p_hdr
->eh_entries
== 0) {
2318 * truncate to zero freed all the tree,
2319 * so we need to correct eh_depth
2321 err
= ext4_ext_get_access(handle
, inode
, path
);
2323 ext_inode_hdr(inode
)->eh_depth
= 0;
2324 ext_inode_hdr(inode
)->eh_max
=
2325 cpu_to_le16(ext4_ext_space_root(inode
));
2326 err
= ext4_ext_dirty(handle
, inode
, path
);
2330 ext4_ext_drop_refs(path
);
2332 ext4_journal_stop(handle
);
2338 * called at mount time
2340 void ext4_ext_init(struct super_block
*sb
)
2343 * possible initialization would be here
2346 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
)) {
2347 printk(KERN_INFO
"EXT4-fs: file extents enabled");
2348 #ifdef AGGRESSIVE_TEST
2349 printk(", aggressive tests");
2351 #ifdef CHECK_BINSEARCH
2352 printk(", check binsearch");
2354 #ifdef EXTENTS_STATS
2358 #ifdef EXTENTS_STATS
2359 spin_lock_init(&EXT4_SB(sb
)->s_ext_stats_lock
);
2360 EXT4_SB(sb
)->s_ext_min
= 1 << 30;
2361 EXT4_SB(sb
)->s_ext_max
= 0;
2367 * called at umount time
2369 void ext4_ext_release(struct super_block
*sb
)
2371 if (!EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
))
2374 #ifdef EXTENTS_STATS
2375 if (EXT4_SB(sb
)->s_ext_blocks
&& EXT4_SB(sb
)->s_ext_extents
) {
2376 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2377 printk(KERN_ERR
"EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2378 sbi
->s_ext_blocks
, sbi
->s_ext_extents
,
2379 sbi
->s_ext_blocks
/ sbi
->s_ext_extents
);
2380 printk(KERN_ERR
"EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2381 sbi
->s_ext_min
, sbi
->s_ext_max
, sbi
->s_depth_max
);
2386 static void bi_complete(struct bio
*bio
, int error
)
2388 complete((struct completion
*)bio
->bi_private
);
2391 /* FIXME!! we need to try to merge to left or right after zero-out */
2392 static int ext4_ext_zeroout(struct inode
*inode
, struct ext4_extent
*ex
)
2396 int blkbits
, blocksize
;
2398 struct completion event
;
2399 unsigned int ee_len
, len
, done
, offset
;
2402 blkbits
= inode
->i_blkbits
;
2403 blocksize
= inode
->i_sb
->s_blocksize
;
2404 ee_len
= ext4_ext_get_actual_len(ex
);
2405 ee_pblock
= ext_pblock(ex
);
2407 /* convert ee_pblock to 512 byte sectors */
2408 ee_pblock
= ee_pblock
<< (blkbits
- 9);
2410 while (ee_len
> 0) {
2412 if (ee_len
> BIO_MAX_PAGES
)
2413 len
= BIO_MAX_PAGES
;
2417 bio
= bio_alloc(GFP_NOIO
, len
);
2418 bio
->bi_sector
= ee_pblock
;
2419 bio
->bi_bdev
= inode
->i_sb
->s_bdev
;
2423 while (done
< len
) {
2424 ret
= bio_add_page(bio
, ZERO_PAGE(0),
2426 if (ret
!= blocksize
) {
2428 * We can't add any more pages because of
2429 * hardware limitations. Start a new bio.
2434 offset
+= blocksize
;
2435 if (offset
>= PAGE_CACHE_SIZE
)
2439 init_completion(&event
);
2440 bio
->bi_private
= &event
;
2441 bio
->bi_end_io
= bi_complete
;
2442 submit_bio(WRITE
, bio
);
2443 wait_for_completion(&event
);
2445 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
2453 ee_pblock
+= done
<< (blkbits
- 9);
2458 #define EXT4_EXT_ZERO_LEN 7
2461 * This function is called by ext4_ext_get_blocks() if someone tries to write
2462 * to an uninitialized extent. It may result in splitting the uninitialized
2463 * extent into multiple extents (upto three - one initialized and two
2465 * There are three possibilities:
2466 * a> There is no split required: Entire extent should be initialized
2467 * b> Splits in two extents: Write is happening at either end of the extent
2468 * c> Splits in three extents: Somone is writing in middle of the extent
2470 static int ext4_ext_convert_to_initialized(handle_t
*handle
,
2471 struct inode
*inode
,
2472 struct ext4_ext_path
*path
,
2474 unsigned int max_blocks
)
2476 struct ext4_extent
*ex
, newex
, orig_ex
;
2477 struct ext4_extent
*ex1
= NULL
;
2478 struct ext4_extent
*ex2
= NULL
;
2479 struct ext4_extent
*ex3
= NULL
;
2480 struct ext4_extent_header
*eh
;
2481 ext4_lblk_t ee_block
;
2482 unsigned int allocated
, ee_len
, depth
;
2483 ext4_fsblk_t newblock
;
2487 depth
= ext_depth(inode
);
2488 eh
= path
[depth
].p_hdr
;
2489 ex
= path
[depth
].p_ext
;
2490 ee_block
= le32_to_cpu(ex
->ee_block
);
2491 ee_len
= ext4_ext_get_actual_len(ex
);
2492 allocated
= ee_len
- (iblock
- ee_block
);
2493 newblock
= iblock
- ee_block
+ ext_pblock(ex
);
2495 orig_ex
.ee_block
= ex
->ee_block
;
2496 orig_ex
.ee_len
= cpu_to_le16(ee_len
);
2497 ext4_ext_store_pblock(&orig_ex
, ext_pblock(ex
));
2499 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2502 /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
2503 if (ee_len
<= 2*EXT4_EXT_ZERO_LEN
) {
2504 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2506 goto fix_extent_len
;
2507 /* update the extent length and mark as initialized */
2508 ex
->ee_block
= orig_ex
.ee_block
;
2509 ex
->ee_len
= orig_ex
.ee_len
;
2510 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2511 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2512 /* zeroed the full extent */
2516 /* ex1: ee_block to iblock - 1 : uninitialized */
2517 if (iblock
> ee_block
) {
2519 ex1
->ee_len
= cpu_to_le16(iblock
- ee_block
);
2520 ext4_ext_mark_uninitialized(ex1
);
2524 * for sanity, update the length of the ex2 extent before
2525 * we insert ex3, if ex1 is NULL. This is to avoid temporary
2526 * overlap of blocks.
2528 if (!ex1
&& allocated
> max_blocks
)
2529 ex2
->ee_len
= cpu_to_le16(max_blocks
);
2530 /* ex3: to ee_block + ee_len : uninitialised */
2531 if (allocated
> max_blocks
) {
2532 unsigned int newdepth
;
2533 /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */
2534 if (allocated
<= EXT4_EXT_ZERO_LEN
) {
2536 * iblock == ee_block is handled by the zerouout
2538 * Mark first half uninitialized.
2539 * Mark second half initialized and zero out the
2540 * initialized extent
2542 ex
->ee_block
= orig_ex
.ee_block
;
2543 ex
->ee_len
= cpu_to_le16(ee_len
- allocated
);
2544 ext4_ext_mark_uninitialized(ex
);
2545 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2546 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2549 ex3
->ee_block
= cpu_to_le32(iblock
);
2550 ext4_ext_store_pblock(ex3
, newblock
);
2551 ex3
->ee_len
= cpu_to_le16(allocated
);
2552 err
= ext4_ext_insert_extent(handle
, inode
, path
, ex3
);
2553 if (err
== -ENOSPC
) {
2554 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2556 goto fix_extent_len
;
2557 ex
->ee_block
= orig_ex
.ee_block
;
2558 ex
->ee_len
= orig_ex
.ee_len
;
2559 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2560 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2561 /* blocks available from iblock */
2565 goto fix_extent_len
;
2568 * We need to zero out the second half because
2569 * an fallocate request can update file size and
2570 * converting the second half to initialized extent
2571 * implies that we can leak some junk data to user
2574 err
= ext4_ext_zeroout(inode
, ex3
);
2577 * We should actually mark the
2578 * second half as uninit and return error
2579 * Insert would have changed the extent
2581 depth
= ext_depth(inode
);
2582 ext4_ext_drop_refs(path
);
2583 path
= ext4_ext_find_extent(inode
,
2586 err
= PTR_ERR(path
);
2589 /* get the second half extent details */
2590 ex
= path
[depth
].p_ext
;
2591 err
= ext4_ext_get_access(handle
, inode
,
2595 ext4_ext_mark_uninitialized(ex
);
2596 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2600 /* zeroed the second half */
2604 ex3
->ee_block
= cpu_to_le32(iblock
+ max_blocks
);
2605 ext4_ext_store_pblock(ex3
, newblock
+ max_blocks
);
2606 ex3
->ee_len
= cpu_to_le16(allocated
- max_blocks
);
2607 ext4_ext_mark_uninitialized(ex3
);
2608 err
= ext4_ext_insert_extent(handle
, inode
, path
, ex3
);
2609 if (err
== -ENOSPC
) {
2610 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2612 goto fix_extent_len
;
2613 /* update the extent length and mark as initialized */
2614 ex
->ee_block
= orig_ex
.ee_block
;
2615 ex
->ee_len
= orig_ex
.ee_len
;
2616 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2617 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2618 /* zeroed the full extent */
2619 /* blocks available from iblock */
2623 goto fix_extent_len
;
2625 * The depth, and hence eh & ex might change
2626 * as part of the insert above.
2628 newdepth
= ext_depth(inode
);
2630 * update the extent length after successful insert of the
2633 orig_ex
.ee_len
= cpu_to_le16(ee_len
-
2634 ext4_ext_get_actual_len(ex3
));
2636 ext4_ext_drop_refs(path
);
2637 path
= ext4_ext_find_extent(inode
, iblock
, path
);
2639 err
= PTR_ERR(path
);
2642 eh
= path
[depth
].p_hdr
;
2643 ex
= path
[depth
].p_ext
;
2647 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2651 allocated
= max_blocks
;
2653 /* If extent has less than EXT4_EXT_ZERO_LEN and we are trying
2654 * to insert a extent in the middle zerout directly
2655 * otherwise give the extent a chance to merge to left
2657 if (le16_to_cpu(orig_ex
.ee_len
) <= EXT4_EXT_ZERO_LEN
&&
2658 iblock
!= ee_block
) {
2659 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2661 goto fix_extent_len
;
2662 /* update the extent length and mark as initialized */
2663 ex
->ee_block
= orig_ex
.ee_block
;
2664 ex
->ee_len
= orig_ex
.ee_len
;
2665 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2666 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2667 /* zero out the first half */
2668 /* blocks available from iblock */
2673 * If there was a change of depth as part of the
2674 * insertion of ex3 above, we need to update the length
2675 * of the ex1 extent again here
2677 if (ex1
&& ex1
!= ex
) {
2679 ex1
->ee_len
= cpu_to_le16(iblock
- ee_block
);
2680 ext4_ext_mark_uninitialized(ex1
);
2683 /* ex2: iblock to iblock + maxblocks-1 : initialised */
2684 ex2
->ee_block
= cpu_to_le32(iblock
);
2685 ext4_ext_store_pblock(ex2
, newblock
);
2686 ex2
->ee_len
= cpu_to_le16(allocated
);
2690 * New (initialized) extent starts from the first block
2691 * in the current extent. i.e., ex2 == ex
2692 * We have to see if it can be merged with the extent
2695 if (ex2
> EXT_FIRST_EXTENT(eh
)) {
2697 * To merge left, pass "ex2 - 1" to try_to_merge(),
2698 * since it merges towards right _only_.
2700 ret
= ext4_ext_try_to_merge(inode
, path
, ex2
- 1);
2702 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2705 depth
= ext_depth(inode
);
2710 * Try to Merge towards right. This might be required
2711 * only when the whole extent is being written to.
2712 * i.e. ex2 == ex and ex3 == NULL.
2715 ret
= ext4_ext_try_to_merge(inode
, path
, ex2
);
2717 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2722 /* Mark modified extent as dirty */
2723 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2726 err
= ext4_ext_insert_extent(handle
, inode
, path
, &newex
);
2727 if (err
== -ENOSPC
) {
2728 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2730 goto fix_extent_len
;
2731 /* update the extent length and mark as initialized */
2732 ex
->ee_block
= orig_ex
.ee_block
;
2733 ex
->ee_len
= orig_ex
.ee_len
;
2734 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2735 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2736 /* zero out the first half */
2739 goto fix_extent_len
;
2741 return err
? err
: allocated
;
2744 ex
->ee_block
= orig_ex
.ee_block
;
2745 ex
->ee_len
= orig_ex
.ee_len
;
2746 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2747 ext4_ext_mark_uninitialized(ex
);
2748 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2753 * Block allocation/map/preallocation routine for extents based files
2756 * Need to be called with
2757 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
2758 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
2760 * return > 0, number of of blocks already mapped/allocated
2761 * if create == 0 and these are pre-allocated blocks
2762 * buffer head is unmapped
2763 * otherwise blocks are mapped
2765 * return = 0, if plain look up failed (blocks have not been allocated)
2766 * buffer head is unmapped
2768 * return < 0, error case.
2770 int ext4_ext_get_blocks(handle_t
*handle
, struct inode
*inode
,
2772 unsigned int max_blocks
, struct buffer_head
*bh_result
,
2775 struct ext4_ext_path
*path
= NULL
;
2776 struct ext4_extent_header
*eh
;
2777 struct ext4_extent newex
, *ex
;
2778 ext4_fsblk_t newblock
;
2779 int err
= 0, depth
, ret
, cache_type
;
2780 unsigned int allocated
= 0;
2781 struct ext4_allocation_request ar
;
2784 __clear_bit(BH_New
, &bh_result
->b_state
);
2785 ext_debug("blocks %u/%u requested for inode %u\n",
2786 iblock
, max_blocks
, inode
->i_ino
);
2788 /* check in cache */
2789 cache_type
= ext4_ext_in_cache(inode
, iblock
, &newex
);
2791 if (cache_type
== EXT4_EXT_CACHE_GAP
) {
2792 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
2794 * block isn't allocated yet and
2795 * user doesn't want to allocate it
2799 /* we should allocate requested block */
2800 } else if (cache_type
== EXT4_EXT_CACHE_EXTENT
) {
2801 /* block is already allocated */
2803 - le32_to_cpu(newex
.ee_block
)
2804 + ext_pblock(&newex
);
2805 /* number of remaining blocks in the extent */
2806 allocated
= ext4_ext_get_actual_len(&newex
) -
2807 (iblock
- le32_to_cpu(newex
.ee_block
));
2814 /* find extent for this block */
2815 path
= ext4_ext_find_extent(inode
, iblock
, NULL
);
2817 err
= PTR_ERR(path
);
2822 depth
= ext_depth(inode
);
2825 * consistent leaf must not be empty;
2826 * this situation is possible, though, _during_ tree modification;
2827 * this is why assert can't be put in ext4_ext_find_extent()
2829 BUG_ON(path
[depth
].p_ext
== NULL
&& depth
!= 0);
2830 eh
= path
[depth
].p_hdr
;
2832 ex
= path
[depth
].p_ext
;
2834 ext4_lblk_t ee_block
= le32_to_cpu(ex
->ee_block
);
2835 ext4_fsblk_t ee_start
= ext_pblock(ex
);
2836 unsigned short ee_len
;
2839 * Uninitialized extents are treated as holes, except that
2840 * we split out initialized portions during a write.
2842 ee_len
= ext4_ext_get_actual_len(ex
);
2843 /* if found extent covers block, simply return it */
2844 if (iblock
>= ee_block
&& iblock
< ee_block
+ ee_len
) {
2845 newblock
= iblock
- ee_block
+ ee_start
;
2846 /* number of remaining blocks in the extent */
2847 allocated
= ee_len
- (iblock
- ee_block
);
2848 ext_debug("%u fit into %lu:%d -> %llu\n", iblock
,
2849 ee_block
, ee_len
, newblock
);
2851 /* Do not put uninitialized extent in the cache */
2852 if (!ext4_ext_is_uninitialized(ex
)) {
2853 ext4_ext_put_in_cache(inode
, ee_block
,
2855 EXT4_EXT_CACHE_EXTENT
);
2858 if (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
)
2860 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
2861 if (allocated
> max_blocks
)
2862 allocated
= max_blocks
;
2864 * We have blocks reserved already. We
2865 * return allocated blocks so that delalloc
2866 * won't do block reservation for us. But
2867 * the buffer head will be unmapped so that
2868 * a read from the block returns 0s.
2870 set_buffer_unwritten(bh_result
);
2871 bh_result
->b_bdev
= inode
->i_sb
->s_bdev
;
2872 bh_result
->b_blocknr
= newblock
;
2876 ret
= ext4_ext_convert_to_initialized(handle
, inode
,
2889 * requested block isn't allocated yet;
2890 * we couldn't try to create block if create flag is zero
2892 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
2894 * put just found gap into cache to speed up
2895 * subsequent requests
2897 ext4_ext_put_gap_in_cache(inode
, path
, iblock
);
2901 * Okay, we need to do block allocation.
2904 /* find neighbour allocated blocks */
2906 err
= ext4_ext_search_left(inode
, path
, &ar
.lleft
, &ar
.pleft
);
2910 err
= ext4_ext_search_right(inode
, path
, &ar
.lright
, &ar
.pright
);
2915 * See if request is beyond maximum number of blocks we can have in
2916 * a single extent. For an initialized extent this limit is
2917 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
2918 * EXT_UNINIT_MAX_LEN.
2920 if (max_blocks
> EXT_INIT_MAX_LEN
&&
2921 !(flags
& EXT4_GET_BLOCKS_UNINIT_EXT
))
2922 max_blocks
= EXT_INIT_MAX_LEN
;
2923 else if (max_blocks
> EXT_UNINIT_MAX_LEN
&&
2924 (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
))
2925 max_blocks
= EXT_UNINIT_MAX_LEN
;
2927 /* Check if we can really insert (iblock)::(iblock+max_blocks) extent */
2928 newex
.ee_block
= cpu_to_le32(iblock
);
2929 newex
.ee_len
= cpu_to_le16(max_blocks
);
2930 err
= ext4_ext_check_overlap(inode
, &newex
, path
);
2932 allocated
= ext4_ext_get_actual_len(&newex
);
2934 allocated
= max_blocks
;
2936 /* allocate new block */
2938 ar
.goal
= ext4_ext_find_goal(inode
, path
, iblock
);
2939 ar
.logical
= iblock
;
2941 if (S_ISREG(inode
->i_mode
))
2942 ar
.flags
= EXT4_MB_HINT_DATA
;
2944 /* disable in-core preallocation for non-regular files */
2946 newblock
= ext4_mb_new_blocks(handle
, &ar
, &err
);
2949 ext_debug("allocate new block: goal %llu, found %llu/%lu\n",
2950 ar
.goal
, newblock
, allocated
);
2952 /* try to insert new extent into found leaf and return */
2953 ext4_ext_store_pblock(&newex
, newblock
);
2954 newex
.ee_len
= cpu_to_le16(ar
.len
);
2955 if (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
) /* Mark uninitialized */
2956 ext4_ext_mark_uninitialized(&newex
);
2957 err
= ext4_ext_insert_extent(handle
, inode
, path
, &newex
);
2959 /* free data blocks we just allocated */
2960 /* not a good idea to call discard here directly,
2961 * but otherwise we'd need to call it every free() */
2962 ext4_discard_preallocations(inode
);
2963 ext4_free_blocks(handle
, inode
, ext_pblock(&newex
),
2964 ext4_ext_get_actual_len(&newex
), 0);
2968 /* previous routine could use block we allocated */
2969 newblock
= ext_pblock(&newex
);
2970 allocated
= ext4_ext_get_actual_len(&newex
);
2972 if (flags
& EXT4_GET_BLOCKS_EXTEND_DISKSIZE
) {
2973 disksize
= ((loff_t
) iblock
+ ar
.len
) << inode
->i_blkbits
;
2974 if (disksize
> i_size_read(inode
))
2975 disksize
= i_size_read(inode
);
2976 if (disksize
> EXT4_I(inode
)->i_disksize
)
2977 EXT4_I(inode
)->i_disksize
= disksize
;
2980 set_buffer_new(bh_result
);
2982 /* Cache only when it is _not_ an uninitialized extent */
2983 if ((flags
& EXT4_GET_BLOCKS_UNINIT_EXT
) == 0)
2984 ext4_ext_put_in_cache(inode
, iblock
, allocated
, newblock
,
2985 EXT4_EXT_CACHE_EXTENT
);
2987 if (allocated
> max_blocks
)
2988 allocated
= max_blocks
;
2989 ext4_ext_show_leaf(inode
, path
);
2990 set_buffer_mapped(bh_result
);
2991 bh_result
->b_bdev
= inode
->i_sb
->s_bdev
;
2992 bh_result
->b_blocknr
= newblock
;
2995 ext4_ext_drop_refs(path
);
2998 return err
? err
: allocated
;
3001 void ext4_ext_truncate(struct inode
*inode
)
3003 struct address_space
*mapping
= inode
->i_mapping
;
3004 struct super_block
*sb
= inode
->i_sb
;
3005 ext4_lblk_t last_block
;
3010 * probably first extent we're gonna free will be last in block
3012 err
= ext4_writepage_trans_blocks(inode
);
3013 handle
= ext4_journal_start(inode
, err
);
3017 if (inode
->i_size
& (sb
->s_blocksize
- 1))
3018 ext4_block_truncate_page(handle
, mapping
, inode
->i_size
);
3020 if (ext4_orphan_add(handle
, inode
))
3023 down_write(&EXT4_I(inode
)->i_data_sem
);
3024 ext4_ext_invalidate_cache(inode
);
3026 ext4_discard_preallocations(inode
);
3029 * TODO: optimization is possible here.
3030 * Probably we need not scan at all,
3031 * because page truncation is enough.
3034 /* we have to know where to truncate from in crash case */
3035 EXT4_I(inode
)->i_disksize
= inode
->i_size
;
3036 ext4_mark_inode_dirty(handle
, inode
);
3038 last_block
= (inode
->i_size
+ sb
->s_blocksize
- 1)
3039 >> EXT4_BLOCK_SIZE_BITS(sb
);
3040 err
= ext4_ext_remove_space(inode
, last_block
);
3042 /* In a multi-transaction truncate, we only make the final
3043 * transaction synchronous.
3046 ext4_handle_sync(handle
);
3049 up_write(&EXT4_I(inode
)->i_data_sem
);
3051 * If this was a simple ftruncate() and the file will remain alive,
3052 * then we need to clear up the orphan record which we created above.
3053 * However, if this was a real unlink then we were called by
3054 * ext4_delete_inode(), and we allow that function to clean up the
3055 * orphan info for us.
3058 ext4_orphan_del(handle
, inode
);
3060 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3061 ext4_mark_inode_dirty(handle
, inode
);
3062 ext4_journal_stop(handle
);
3065 static void ext4_falloc_update_inode(struct inode
*inode
,
3066 int mode
, loff_t new_size
, int update_ctime
)
3068 struct timespec now
;
3071 now
= current_fs_time(inode
->i_sb
);
3072 if (!timespec_equal(&inode
->i_ctime
, &now
))
3073 inode
->i_ctime
= now
;
3076 * Update only when preallocation was requested beyond
3079 if (!(mode
& FALLOC_FL_KEEP_SIZE
)) {
3080 if (new_size
> i_size_read(inode
))
3081 i_size_write(inode
, new_size
);
3082 if (new_size
> EXT4_I(inode
)->i_disksize
)
3083 ext4_update_i_disksize(inode
, new_size
);
3089 * preallocate space for a file. This implements ext4's fallocate inode
3090 * operation, which gets called from sys_fallocate system call.
3091 * For block-mapped files, posix_fallocate should fall back to the method
3092 * of writing zeroes to the required new blocks (the same behavior which is
3093 * expected for file systems which do not support fallocate() system call).
3095 long ext4_fallocate(struct inode
*inode
, int mode
, loff_t offset
, loff_t len
)
3100 unsigned int max_blocks
;
3104 struct buffer_head map_bh
;
3105 unsigned int credits
, blkbits
= inode
->i_blkbits
;
3108 * currently supporting (pre)allocate mode for extent-based
3111 if (!(EXT4_I(inode
)->i_flags
& EXT4_EXTENTS_FL
))
3114 /* preallocation to directories is currently not supported */
3115 if (S_ISDIR(inode
->i_mode
))
3118 block
= offset
>> blkbits
;
3120 * We can't just convert len to max_blocks because
3121 * If blocksize = 4096 offset = 3072 and len = 2048
3123 max_blocks
= (EXT4_BLOCK_ALIGN(len
+ offset
, blkbits
) >> blkbits
)
3126 * credits to insert 1 extent into extent tree
3128 credits
= ext4_chunk_trans_blocks(inode
, max_blocks
);
3129 mutex_lock(&inode
->i_mutex
);
3131 while (ret
>= 0 && ret
< max_blocks
) {
3132 block
= block
+ ret
;
3133 max_blocks
= max_blocks
- ret
;
3134 handle
= ext4_journal_start(inode
, credits
);
3135 if (IS_ERR(handle
)) {
3136 ret
= PTR_ERR(handle
);
3140 ret
= ext4_get_blocks(handle
, inode
, block
,
3141 max_blocks
, &map_bh
,
3142 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT
);
3146 printk(KERN_ERR
"%s: ext4_ext_get_blocks "
3147 "returned error inode#%lu, block=%u, "
3148 "max_blocks=%u", __func__
,
3149 inode
->i_ino
, block
, max_blocks
);
3151 ext4_mark_inode_dirty(handle
, inode
);
3152 ret2
= ext4_journal_stop(handle
);
3155 if ((block
+ ret
) >= (EXT4_BLOCK_ALIGN(offset
+ len
,
3156 blkbits
) >> blkbits
))
3157 new_size
= offset
+ len
;
3159 new_size
= (block
+ ret
) << blkbits
;
3161 ext4_falloc_update_inode(inode
, mode
, new_size
,
3162 buffer_new(&map_bh
));
3163 ext4_mark_inode_dirty(handle
, inode
);
3164 ret2
= ext4_journal_stop(handle
);
3168 if (ret
== -ENOSPC
&&
3169 ext4_should_retry_alloc(inode
->i_sb
, &retries
)) {
3173 mutex_unlock(&inode
->i_mutex
);
3174 return ret
> 0 ? ret2
: ret
;
3178 * Callback function called for each extent to gather FIEMAP information.
3180 static int ext4_ext_fiemap_cb(struct inode
*inode
, struct ext4_ext_path
*path
,
3181 struct ext4_ext_cache
*newex
, struct ext4_extent
*ex
,
3184 struct fiemap_extent_info
*fieinfo
= data
;
3185 unsigned char blksize_bits
= inode
->i_sb
->s_blocksize_bits
;
3192 logical
= (__u64
)newex
->ec_block
<< blksize_bits
;
3194 if (newex
->ec_type
== EXT4_EXT_CACHE_GAP
) {
3197 struct buffer_head
*bh
= NULL
;
3199 offset
= logical
>> PAGE_SHIFT
;
3200 page
= find_get_page(inode
->i_mapping
, offset
);
3201 if (!page
|| !page_has_buffers(page
))
3202 return EXT_CONTINUE
;
3204 bh
= page_buffers(page
);
3207 return EXT_CONTINUE
;
3209 if (buffer_delay(bh
)) {
3210 flags
|= FIEMAP_EXTENT_DELALLOC
;
3211 page_cache_release(page
);
3213 page_cache_release(page
);
3214 return EXT_CONTINUE
;
3218 physical
= (__u64
)newex
->ec_start
<< blksize_bits
;
3219 length
= (__u64
)newex
->ec_len
<< blksize_bits
;
3221 if (ex
&& ext4_ext_is_uninitialized(ex
))
3222 flags
|= FIEMAP_EXTENT_UNWRITTEN
;
3225 * If this extent reaches EXT_MAX_BLOCK, it must be last.
3227 * Or if ext4_ext_next_allocated_block is EXT_MAX_BLOCK,
3228 * this also indicates no more allocated blocks.
3230 * XXX this might miss a single-block extent at EXT_MAX_BLOCK
3232 if (ext4_ext_next_allocated_block(path
) == EXT_MAX_BLOCK
||
3233 newex
->ec_block
+ newex
->ec_len
- 1 == EXT_MAX_BLOCK
) {
3234 loff_t size
= i_size_read(inode
);
3235 loff_t bs
= EXT4_BLOCK_SIZE(inode
->i_sb
);
3237 flags
|= FIEMAP_EXTENT_LAST
;
3238 if ((flags
& FIEMAP_EXTENT_DELALLOC
) &&
3239 logical
+length
> size
)
3240 length
= (size
- logical
+ bs
- 1) & ~(bs
-1);
3243 error
= fiemap_fill_next_extent(fieinfo
, logical
, physical
,
3250 return EXT_CONTINUE
;
3253 /* fiemap flags we can handle specified here */
3254 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
3256 static int ext4_xattr_fiemap(struct inode
*inode
,
3257 struct fiemap_extent_info
*fieinfo
)
3261 __u32 flags
= FIEMAP_EXTENT_LAST
;
3262 int blockbits
= inode
->i_sb
->s_blocksize_bits
;
3266 if (EXT4_I(inode
)->i_state
& EXT4_STATE_XATTR
) {
3267 struct ext4_iloc iloc
;
3268 int offset
; /* offset of xattr in inode */
3270 error
= ext4_get_inode_loc(inode
, &iloc
);
3273 physical
= iloc
.bh
->b_blocknr
<< blockbits
;
3274 offset
= EXT4_GOOD_OLD_INODE_SIZE
+
3275 EXT4_I(inode
)->i_extra_isize
;
3277 length
= EXT4_SB(inode
->i_sb
)->s_inode_size
- offset
;
3278 flags
|= FIEMAP_EXTENT_DATA_INLINE
;
3279 } else { /* external block */
3280 physical
= EXT4_I(inode
)->i_file_acl
<< blockbits
;
3281 length
= inode
->i_sb
->s_blocksize
;
3285 error
= fiemap_fill_next_extent(fieinfo
, 0, physical
,
3287 return (error
< 0 ? error
: 0);
3290 int ext4_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
3291 __u64 start
, __u64 len
)
3293 ext4_lblk_t start_blk
;
3294 ext4_lblk_t len_blks
;
3297 /* fallback to generic here if not in extents fmt */
3298 if (!(EXT4_I(inode
)->i_flags
& EXT4_EXTENTS_FL
))
3299 return generic_block_fiemap(inode
, fieinfo
, start
, len
,
3302 if (fiemap_check_flags(fieinfo
, EXT4_FIEMAP_FLAGS
))
3305 if (fieinfo
->fi_flags
& FIEMAP_FLAG_XATTR
) {
3306 error
= ext4_xattr_fiemap(inode
, fieinfo
);
3308 start_blk
= start
>> inode
->i_sb
->s_blocksize_bits
;
3309 len_blks
= len
>> inode
->i_sb
->s_blocksize_bits
;
3312 * Walk the extent tree gathering extent information.
3313 * ext4_ext_fiemap_cb will push extents back to user.
3315 down_write(&EXT4_I(inode
)->i_data_sem
);
3316 error
= ext4_ext_walk_space(inode
, start_blk
, len_blks
,
3317 ext4_ext_fiemap_cb
, fieinfo
);
3318 up_write(&EXT4_I(inode
)->i_data_sem
);