2 * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
3 * Written by Alex Tomas <alex@clusterfs.com>
5 * Architecture independence:
6 * Copyright (c) 2005, Bull S.A.
7 * Written by Pierre Peiffer <pierre.peiffer@bull.net>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public Licens
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
24 * Extents support for EXT4
27 * - ext4*_error() should be used in some situations
28 * - analyze all BUG()/BUG_ON(), use -EIO where appropriate
29 * - smart tree reduction
32 #include <linux/module.h>
34 #include <linux/time.h>
35 #include <linux/jbd2.h>
36 #include <linux/highuid.h>
37 #include <linux/pagemap.h>
38 #include <linux/quotaops.h>
39 #include <linux/string.h>
40 #include <linux/slab.h>
41 #include <linux/falloc.h>
42 #include <asm/uaccess.h>
43 #include <linux/fiemap.h>
44 #include "ext4_jbd2.h"
45 #include "ext4_extents.h"
50 * combine low and high parts of physical block number into ext4_fsblk_t
52 ext4_fsblk_t
ext_pblock(struct ext4_extent
*ex
)
56 block
= le32_to_cpu(ex
->ee_start_lo
);
57 block
|= ((ext4_fsblk_t
) le16_to_cpu(ex
->ee_start_hi
) << 31) << 1;
63 * combine low and high parts of a leaf physical block number into ext4_fsblk_t
65 ext4_fsblk_t
idx_pblock(struct ext4_extent_idx
*ix
)
69 block
= le32_to_cpu(ix
->ei_leaf_lo
);
70 block
|= ((ext4_fsblk_t
) le16_to_cpu(ix
->ei_leaf_hi
) << 31) << 1;
75 * ext4_ext_store_pblock:
76 * stores a large physical block number into an extent struct,
77 * breaking it into parts
79 void ext4_ext_store_pblock(struct ext4_extent
*ex
, ext4_fsblk_t pb
)
81 ex
->ee_start_lo
= cpu_to_le32((unsigned long) (pb
& 0xffffffff));
82 ex
->ee_start_hi
= cpu_to_le16((unsigned long) ((pb
>> 31) >> 1) & 0xffff);
86 * ext4_idx_store_pblock:
87 * stores a large physical block number into an index struct,
88 * breaking it into parts
90 static void ext4_idx_store_pblock(struct ext4_extent_idx
*ix
, ext4_fsblk_t pb
)
92 ix
->ei_leaf_lo
= cpu_to_le32((unsigned long) (pb
& 0xffffffff));
93 ix
->ei_leaf_hi
= cpu_to_le16((unsigned long) ((pb
>> 31) >> 1) & 0xffff);
96 static int ext4_ext_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]%d:%llu ",
441 le32_to_cpu(path
->p_ext
->ee_block
),
442 ext4_ext_is_uninitialized(path
->p_ext
),
443 ext4_ext_get_actual_len(path
->p_ext
),
444 ext_pblock(path
->p_ext
));
451 static void ext4_ext_show_leaf(struct inode
*inode
, struct ext4_ext_path
*path
)
453 int depth
= ext_depth(inode
);
454 struct ext4_extent_header
*eh
;
455 struct ext4_extent
*ex
;
461 eh
= path
[depth
].p_hdr
;
462 ex
= EXT_FIRST_EXTENT(eh
);
464 ext_debug("Displaying leaf extents for inode %lu\n", inode
->i_ino
);
466 for (i
= 0; i
< le16_to_cpu(eh
->eh_entries
); i
++, ex
++) {
467 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex
->ee_block
),
468 ext4_ext_is_uninitialized(ex
),
469 ext4_ext_get_actual_len(ex
), ext_pblock(ex
));
474 #define ext4_ext_show_path(inode, path)
475 #define ext4_ext_show_leaf(inode, path)
478 void ext4_ext_drop_refs(struct ext4_ext_path
*path
)
480 int depth
= path
->p_depth
;
483 for (i
= 0; i
<= depth
; i
++, path
++)
491 * ext4_ext_binsearch_idx:
492 * binary search for the closest index of the given block
493 * the header must be checked before calling this
496 ext4_ext_binsearch_idx(struct inode
*inode
,
497 struct ext4_ext_path
*path
, ext4_lblk_t block
)
499 struct ext4_extent_header
*eh
= path
->p_hdr
;
500 struct ext4_extent_idx
*r
, *l
, *m
;
503 ext_debug("binsearch for %u(idx): ", block
);
505 l
= EXT_FIRST_INDEX(eh
) + 1;
506 r
= EXT_LAST_INDEX(eh
);
509 if (block
< le32_to_cpu(m
->ei_block
))
513 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ei_block
),
514 m
, le32_to_cpu(m
->ei_block
),
515 r
, le32_to_cpu(r
->ei_block
));
519 ext_debug(" -> %d->%lld ", le32_to_cpu(path
->p_idx
->ei_block
),
520 idx_pblock(path
->p_idx
));
522 #ifdef CHECK_BINSEARCH
524 struct ext4_extent_idx
*chix
, *ix
;
527 chix
= ix
= EXT_FIRST_INDEX(eh
);
528 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ix
++) {
530 le32_to_cpu(ix
->ei_block
) <= le32_to_cpu(ix
[-1].ei_block
)) {
531 printk(KERN_DEBUG
"k=%d, ix=0x%p, "
533 ix
, EXT_FIRST_INDEX(eh
));
534 printk(KERN_DEBUG
"%u <= %u\n",
535 le32_to_cpu(ix
->ei_block
),
536 le32_to_cpu(ix
[-1].ei_block
));
538 BUG_ON(k
&& le32_to_cpu(ix
->ei_block
)
539 <= le32_to_cpu(ix
[-1].ei_block
));
540 if (block
< le32_to_cpu(ix
->ei_block
))
544 BUG_ON(chix
!= path
->p_idx
);
551 * ext4_ext_binsearch:
552 * binary search for closest extent of the given block
553 * the header must be checked before calling this
556 ext4_ext_binsearch(struct inode
*inode
,
557 struct ext4_ext_path
*path
, ext4_lblk_t block
)
559 struct ext4_extent_header
*eh
= path
->p_hdr
;
560 struct ext4_extent
*r
, *l
, *m
;
562 if (eh
->eh_entries
== 0) {
564 * this leaf is empty:
565 * we get such a leaf in split/add case
570 ext_debug("binsearch for %u: ", block
);
572 l
= EXT_FIRST_EXTENT(eh
) + 1;
573 r
= EXT_LAST_EXTENT(eh
);
577 if (block
< le32_to_cpu(m
->ee_block
))
581 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ee_block
),
582 m
, le32_to_cpu(m
->ee_block
),
583 r
, le32_to_cpu(r
->ee_block
));
587 ext_debug(" -> %d:%llu:[%d]%d ",
588 le32_to_cpu(path
->p_ext
->ee_block
),
589 ext_pblock(path
->p_ext
),
590 ext4_ext_is_uninitialized(path
->p_ext
),
591 ext4_ext_get_actual_len(path
->p_ext
));
593 #ifdef CHECK_BINSEARCH
595 struct ext4_extent
*chex
, *ex
;
598 chex
= ex
= EXT_FIRST_EXTENT(eh
);
599 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ex
++) {
600 BUG_ON(k
&& le32_to_cpu(ex
->ee_block
)
601 <= le32_to_cpu(ex
[-1].ee_block
));
602 if (block
< le32_to_cpu(ex
->ee_block
))
606 BUG_ON(chex
!= path
->p_ext
);
612 int ext4_ext_tree_init(handle_t
*handle
, struct inode
*inode
)
614 struct ext4_extent_header
*eh
;
616 eh
= ext_inode_hdr(inode
);
619 eh
->eh_magic
= EXT4_EXT_MAGIC
;
620 eh
->eh_max
= cpu_to_le16(ext4_ext_space_root(inode
));
621 ext4_mark_inode_dirty(handle
, inode
);
622 ext4_ext_invalidate_cache(inode
);
626 struct ext4_ext_path
*
627 ext4_ext_find_extent(struct inode
*inode
, ext4_lblk_t block
,
628 struct ext4_ext_path
*path
)
630 struct ext4_extent_header
*eh
;
631 struct buffer_head
*bh
;
632 short int depth
, i
, ppos
= 0, alloc
= 0;
634 eh
= ext_inode_hdr(inode
);
635 depth
= ext_depth(inode
);
637 /* account possible depth increase */
639 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 2),
642 return ERR_PTR(-ENOMEM
);
649 /* walk through the tree */
651 int need_to_validate
= 0;
653 ext_debug("depth %d: num %d, max %d\n",
654 ppos
, le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
656 ext4_ext_binsearch_idx(inode
, path
+ ppos
, block
);
657 path
[ppos
].p_block
= idx_pblock(path
[ppos
].p_idx
);
658 path
[ppos
].p_depth
= i
;
659 path
[ppos
].p_ext
= NULL
;
661 bh
= sb_getblk(inode
->i_sb
, path
[ppos
].p_block
);
664 if (!bh_uptodate_or_lock(bh
)) {
665 if (bh_submit_read(bh
) < 0) {
669 /* validate the extent entries */
670 need_to_validate
= 1;
672 eh
= ext_block_hdr(bh
);
674 BUG_ON(ppos
> depth
);
675 path
[ppos
].p_bh
= bh
;
676 path
[ppos
].p_hdr
= eh
;
679 if (need_to_validate
&& ext4_ext_check(inode
, eh
, i
))
683 path
[ppos
].p_depth
= i
;
684 path
[ppos
].p_ext
= NULL
;
685 path
[ppos
].p_idx
= NULL
;
688 ext4_ext_binsearch(inode
, path
+ ppos
, block
);
689 /* if not an empty leaf */
690 if (path
[ppos
].p_ext
)
691 path
[ppos
].p_block
= ext_pblock(path
[ppos
].p_ext
);
693 ext4_ext_show_path(inode
, path
);
698 ext4_ext_drop_refs(path
);
701 return ERR_PTR(-EIO
);
705 * ext4_ext_insert_index:
706 * insert new index [@logical;@ptr] into the block at @curp;
707 * check where to insert: before @curp or after @curp
709 static int ext4_ext_insert_index(handle_t
*handle
, struct inode
*inode
,
710 struct ext4_ext_path
*curp
,
711 int logical
, ext4_fsblk_t ptr
)
713 struct ext4_extent_idx
*ix
;
716 err
= ext4_ext_get_access(handle
, inode
, curp
);
720 BUG_ON(logical
== le32_to_cpu(curp
->p_idx
->ei_block
));
721 len
= EXT_MAX_INDEX(curp
->p_hdr
) - curp
->p_idx
;
722 if (logical
> le32_to_cpu(curp
->p_idx
->ei_block
)) {
724 if (curp
->p_idx
!= EXT_LAST_INDEX(curp
->p_hdr
)) {
725 len
= (len
- 1) * sizeof(struct ext4_extent_idx
);
726 len
= len
< 0 ? 0 : len
;
727 ext_debug("insert new index %d after: %llu. "
728 "move %d from 0x%p to 0x%p\n",
730 (curp
->p_idx
+ 1), (curp
->p_idx
+ 2));
731 memmove(curp
->p_idx
+ 2, curp
->p_idx
+ 1, len
);
733 ix
= curp
->p_idx
+ 1;
736 len
= len
* sizeof(struct ext4_extent_idx
);
737 len
= len
< 0 ? 0 : len
;
738 ext_debug("insert new index %d before: %llu. "
739 "move %d from 0x%p to 0x%p\n",
741 curp
->p_idx
, (curp
->p_idx
+ 1));
742 memmove(curp
->p_idx
+ 1, curp
->p_idx
, len
);
746 ix
->ei_block
= cpu_to_le32(logical
);
747 ext4_idx_store_pblock(ix
, ptr
);
748 le16_add_cpu(&curp
->p_hdr
->eh_entries
, 1);
750 BUG_ON(le16_to_cpu(curp
->p_hdr
->eh_entries
)
751 > le16_to_cpu(curp
->p_hdr
->eh_max
));
752 BUG_ON(ix
> EXT_LAST_INDEX(curp
->p_hdr
));
754 err
= ext4_ext_dirty(handle
, inode
, curp
);
755 ext4_std_error(inode
->i_sb
, err
);
762 * inserts new subtree into the path, using free index entry
764 * - allocates all needed blocks (new leaf and all intermediate index blocks)
765 * - makes decision where to split
766 * - moves remaining extents and index entries (right to the split point)
767 * into the newly allocated blocks
768 * - initializes subtree
770 static int ext4_ext_split(handle_t
*handle
, struct inode
*inode
,
771 struct ext4_ext_path
*path
,
772 struct ext4_extent
*newext
, int at
)
774 struct buffer_head
*bh
= NULL
;
775 int depth
= ext_depth(inode
);
776 struct ext4_extent_header
*neh
;
777 struct ext4_extent_idx
*fidx
;
778 struct ext4_extent
*ex
;
780 ext4_fsblk_t newblock
, oldblock
;
782 ext4_fsblk_t
*ablocks
= NULL
; /* array of allocated blocks */
785 /* make decision: where to split? */
786 /* FIXME: now decision is simplest: at current extent */
788 /* if current leaf will be split, then we should use
789 * border from split point */
790 BUG_ON(path
[depth
].p_ext
> EXT_MAX_EXTENT(path
[depth
].p_hdr
));
791 if (path
[depth
].p_ext
!= EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
792 border
= path
[depth
].p_ext
[1].ee_block
;
793 ext_debug("leaf will be split."
794 " next leaf starts at %d\n",
795 le32_to_cpu(border
));
797 border
= newext
->ee_block
;
798 ext_debug("leaf will be added."
799 " next leaf starts at %d\n",
800 le32_to_cpu(border
));
804 * If error occurs, then we break processing
805 * and mark filesystem read-only. index won't
806 * be inserted and tree will be in consistent
807 * state. Next mount will repair buffers too.
811 * Get array to track all allocated blocks.
812 * We need this to handle errors and free blocks
815 ablocks
= kzalloc(sizeof(ext4_fsblk_t
) * depth
, GFP_NOFS
);
819 /* allocate all needed blocks */
820 ext_debug("allocate %d blocks for indexes/leaf\n", depth
- at
);
821 for (a
= 0; a
< depth
- at
; a
++) {
822 newblock
= ext4_ext_new_meta_block(handle
, inode
, path
,
826 ablocks
[a
] = newblock
;
829 /* initialize new leaf */
830 newblock
= ablocks
[--a
];
831 BUG_ON(newblock
== 0);
832 bh
= sb_getblk(inode
->i_sb
, newblock
);
839 err
= ext4_journal_get_create_access(handle
, bh
);
843 neh
= ext_block_hdr(bh
);
845 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
));
846 neh
->eh_magic
= EXT4_EXT_MAGIC
;
848 ex
= EXT_FIRST_EXTENT(neh
);
850 /* move remainder of path[depth] to the new leaf */
851 BUG_ON(path
[depth
].p_hdr
->eh_entries
!= path
[depth
].p_hdr
->eh_max
);
852 /* start copy from next extent */
853 /* TODO: we could do it by single memmove */
856 while (path
[depth
].p_ext
<=
857 EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
858 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
859 le32_to_cpu(path
[depth
].p_ext
->ee_block
),
860 ext_pblock(path
[depth
].p_ext
),
861 ext4_ext_is_uninitialized(path
[depth
].p_ext
),
862 ext4_ext_get_actual_len(path
[depth
].p_ext
),
864 /*memmove(ex++, path[depth].p_ext++,
865 sizeof(struct ext4_extent));
871 memmove(ex
, path
[depth
].p_ext
-m
, sizeof(struct ext4_extent
)*m
);
872 le16_add_cpu(&neh
->eh_entries
, m
);
875 set_buffer_uptodate(bh
);
878 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
884 /* correct old leaf */
886 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
889 le16_add_cpu(&path
[depth
].p_hdr
->eh_entries
, -m
);
890 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
896 /* create intermediate indexes */
900 ext_debug("create %d intermediate indices\n", k
);
901 /* insert new index into current index block */
902 /* current depth stored in i var */
906 newblock
= ablocks
[--a
];
907 bh
= sb_getblk(inode
->i_sb
, newblock
);
914 err
= ext4_journal_get_create_access(handle
, bh
);
918 neh
= ext_block_hdr(bh
);
919 neh
->eh_entries
= cpu_to_le16(1);
920 neh
->eh_magic
= EXT4_EXT_MAGIC
;
921 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
));
922 neh
->eh_depth
= cpu_to_le16(depth
- i
);
923 fidx
= EXT_FIRST_INDEX(neh
);
924 fidx
->ei_block
= border
;
925 ext4_idx_store_pblock(fidx
, oldblock
);
927 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
928 i
, newblock
, le32_to_cpu(border
), oldblock
);
933 ext_debug("cur 0x%p, last 0x%p\n", path
[i
].p_idx
,
934 EXT_MAX_INDEX(path
[i
].p_hdr
));
935 BUG_ON(EXT_MAX_INDEX(path
[i
].p_hdr
) !=
936 EXT_LAST_INDEX(path
[i
].p_hdr
));
937 while (path
[i
].p_idx
<= EXT_MAX_INDEX(path
[i
].p_hdr
)) {
938 ext_debug("%d: move %d:%llu in new index %llu\n", i
,
939 le32_to_cpu(path
[i
].p_idx
->ei_block
),
940 idx_pblock(path
[i
].p_idx
),
942 /*memmove(++fidx, path[i].p_idx++,
943 sizeof(struct ext4_extent_idx));
945 BUG_ON(neh->eh_entries > neh->eh_max);*/
950 memmove(++fidx
, path
[i
].p_idx
- m
,
951 sizeof(struct ext4_extent_idx
) * m
);
952 le16_add_cpu(&neh
->eh_entries
, m
);
954 set_buffer_uptodate(bh
);
957 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
963 /* correct old index */
965 err
= ext4_ext_get_access(handle
, inode
, path
+ i
);
968 le16_add_cpu(&path
[i
].p_hdr
->eh_entries
, -m
);
969 err
= ext4_ext_dirty(handle
, inode
, path
+ i
);
977 /* insert new index */
978 err
= ext4_ext_insert_index(handle
, inode
, path
+ at
,
979 le32_to_cpu(border
), newblock
);
983 if (buffer_locked(bh
))
989 /* free all allocated blocks in error case */
990 for (i
= 0; i
< depth
; i
++) {
993 ext4_free_blocks(handle
, inode
, ablocks
[i
], 1, 1);
1002 * ext4_ext_grow_indepth:
1003 * implements tree growing procedure:
1004 * - allocates new block
1005 * - moves top-level data (index block or leaf) into the new block
1006 * - initializes new top-level, creating index that points to the
1007 * just created block
1009 static int ext4_ext_grow_indepth(handle_t
*handle
, struct inode
*inode
,
1010 struct ext4_ext_path
*path
,
1011 struct ext4_extent
*newext
)
1013 struct ext4_ext_path
*curp
= path
;
1014 struct ext4_extent_header
*neh
;
1015 struct ext4_extent_idx
*fidx
;
1016 struct buffer_head
*bh
;
1017 ext4_fsblk_t newblock
;
1020 newblock
= ext4_ext_new_meta_block(handle
, inode
, path
, newext
, &err
);
1024 bh
= sb_getblk(inode
->i_sb
, newblock
);
1027 ext4_std_error(inode
->i_sb
, err
);
1032 err
= ext4_journal_get_create_access(handle
, bh
);
1038 /* move top-level index/leaf into new block */
1039 memmove(bh
->b_data
, curp
->p_hdr
, sizeof(EXT4_I(inode
)->i_data
));
1041 /* set size of new block */
1042 neh
= ext_block_hdr(bh
);
1043 /* old root could have indexes or leaves
1044 * so calculate e_max right way */
1045 if (ext_depth(inode
))
1046 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
));
1048 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
));
1049 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1050 set_buffer_uptodate(bh
);
1053 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1057 /* create index in new top-level index: num,max,pointer */
1058 err
= ext4_ext_get_access(handle
, inode
, curp
);
1062 curp
->p_hdr
->eh_magic
= EXT4_EXT_MAGIC
;
1063 curp
->p_hdr
->eh_max
= cpu_to_le16(ext4_ext_space_root_idx(inode
));
1064 curp
->p_hdr
->eh_entries
= cpu_to_le16(1);
1065 curp
->p_idx
= EXT_FIRST_INDEX(curp
->p_hdr
);
1067 if (path
[0].p_hdr
->eh_depth
)
1068 curp
->p_idx
->ei_block
=
1069 EXT_FIRST_INDEX(path
[0].p_hdr
)->ei_block
;
1071 curp
->p_idx
->ei_block
=
1072 EXT_FIRST_EXTENT(path
[0].p_hdr
)->ee_block
;
1073 ext4_idx_store_pblock(curp
->p_idx
, newblock
);
1075 neh
= ext_inode_hdr(inode
);
1076 fidx
= EXT_FIRST_INDEX(neh
);
1077 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1078 le16_to_cpu(neh
->eh_entries
), le16_to_cpu(neh
->eh_max
),
1079 le32_to_cpu(fidx
->ei_block
), idx_pblock(fidx
));
1081 neh
->eh_depth
= cpu_to_le16(path
->p_depth
+ 1);
1082 err
= ext4_ext_dirty(handle
, inode
, curp
);
1090 * ext4_ext_create_new_leaf:
1091 * finds empty index and adds new leaf.
1092 * if no free index is found, then it requests in-depth growing.
1094 static int ext4_ext_create_new_leaf(handle_t
*handle
, struct inode
*inode
,
1095 struct ext4_ext_path
*path
,
1096 struct ext4_extent
*newext
)
1098 struct ext4_ext_path
*curp
;
1099 int depth
, i
, err
= 0;
1102 i
= depth
= ext_depth(inode
);
1104 /* walk up to the tree and look for free index entry */
1105 curp
= path
+ depth
;
1106 while (i
> 0 && !EXT_HAS_FREE_INDEX(curp
)) {
1111 /* we use already allocated block for index block,
1112 * so subsequent data blocks should be contiguous */
1113 if (EXT_HAS_FREE_INDEX(curp
)) {
1114 /* if we found index with free entry, then use that
1115 * entry: create all needed subtree and add new leaf */
1116 err
= ext4_ext_split(handle
, inode
, path
, newext
, i
);
1121 ext4_ext_drop_refs(path
);
1122 path
= ext4_ext_find_extent(inode
,
1123 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1126 err
= PTR_ERR(path
);
1128 /* tree is full, time to grow in depth */
1129 err
= ext4_ext_grow_indepth(handle
, inode
, path
, newext
);
1134 ext4_ext_drop_refs(path
);
1135 path
= ext4_ext_find_extent(inode
,
1136 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1139 err
= PTR_ERR(path
);
1144 * only first (depth 0 -> 1) produces free space;
1145 * in all other cases we have to split the grown tree
1147 depth
= ext_depth(inode
);
1148 if (path
[depth
].p_hdr
->eh_entries
== path
[depth
].p_hdr
->eh_max
) {
1149 /* now we need to split */
1159 * search the closest allocated block to the left for *logical
1160 * and returns it at @logical + it's physical address at @phys
1161 * if *logical is the smallest allocated block, the function
1162 * returns 0 at @phys
1163 * return value contains 0 (success) or error code
1166 ext4_ext_search_left(struct inode
*inode
, struct ext4_ext_path
*path
,
1167 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
)
1169 struct ext4_extent_idx
*ix
;
1170 struct ext4_extent
*ex
;
1173 BUG_ON(path
== NULL
);
1174 depth
= path
->p_depth
;
1177 if (depth
== 0 && path
->p_ext
== NULL
)
1180 /* usually extent in the path covers blocks smaller
1181 * then *logical, but it can be that extent is the
1182 * first one in the file */
1184 ex
= path
[depth
].p_ext
;
1185 ee_len
= ext4_ext_get_actual_len(ex
);
1186 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1187 BUG_ON(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
);
1188 while (--depth
>= 0) {
1189 ix
= path
[depth
].p_idx
;
1190 BUG_ON(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
));
1195 BUG_ON(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
));
1197 *logical
= le32_to_cpu(ex
->ee_block
) + ee_len
- 1;
1198 *phys
= ext_pblock(ex
) + ee_len
- 1;
1203 * search the closest allocated block to the right for *logical
1204 * and returns it at @logical + it's physical address at @phys
1205 * if *logical is the smallest allocated block, the function
1206 * returns 0 at @phys
1207 * return value contains 0 (success) or error code
1210 ext4_ext_search_right(struct inode
*inode
, struct ext4_ext_path
*path
,
1211 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
)
1213 struct buffer_head
*bh
= NULL
;
1214 struct ext4_extent_header
*eh
;
1215 struct ext4_extent_idx
*ix
;
1216 struct ext4_extent
*ex
;
1218 int depth
; /* Note, NOT eh_depth; depth from top of tree */
1221 BUG_ON(path
== NULL
);
1222 depth
= path
->p_depth
;
1225 if (depth
== 0 && path
->p_ext
== NULL
)
1228 /* usually extent in the path covers blocks smaller
1229 * then *logical, but it can be that extent is the
1230 * first one in the file */
1232 ex
= path
[depth
].p_ext
;
1233 ee_len
= ext4_ext_get_actual_len(ex
);
1234 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1235 BUG_ON(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
);
1236 while (--depth
>= 0) {
1237 ix
= path
[depth
].p_idx
;
1238 BUG_ON(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
));
1240 *logical
= le32_to_cpu(ex
->ee_block
);
1241 *phys
= ext_pblock(ex
);
1245 BUG_ON(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
));
1247 if (ex
!= EXT_LAST_EXTENT(path
[depth
].p_hdr
)) {
1248 /* next allocated block in this leaf */
1250 *logical
= le32_to_cpu(ex
->ee_block
);
1251 *phys
= ext_pblock(ex
);
1255 /* go up and search for index to the right */
1256 while (--depth
>= 0) {
1257 ix
= path
[depth
].p_idx
;
1258 if (ix
!= EXT_LAST_INDEX(path
[depth
].p_hdr
))
1262 /* we've gone up to the root and found no index to the right */
1266 /* we've found index to the right, let's
1267 * follow it and find the closest allocated
1268 * block to the right */
1270 block
= idx_pblock(ix
);
1271 while (++depth
< path
->p_depth
) {
1272 bh
= sb_bread(inode
->i_sb
, block
);
1275 eh
= ext_block_hdr(bh
);
1276 /* subtract from p_depth to get proper eh_depth */
1277 if (ext4_ext_check(inode
, eh
, path
->p_depth
- depth
)) {
1281 ix
= EXT_FIRST_INDEX(eh
);
1282 block
= idx_pblock(ix
);
1286 bh
= sb_bread(inode
->i_sb
, block
);
1289 eh
= ext_block_hdr(bh
);
1290 if (ext4_ext_check(inode
, eh
, path
->p_depth
- depth
)) {
1294 ex
= EXT_FIRST_EXTENT(eh
);
1295 *logical
= le32_to_cpu(ex
->ee_block
);
1296 *phys
= ext_pblock(ex
);
1302 * ext4_ext_next_allocated_block:
1303 * returns allocated block in subsequent extent or EXT_MAX_BLOCK.
1304 * NOTE: it considers block number from index entry as
1305 * allocated block. Thus, index entries have to be consistent
1309 ext4_ext_next_allocated_block(struct ext4_ext_path
*path
)
1313 BUG_ON(path
== NULL
);
1314 depth
= path
->p_depth
;
1316 if (depth
== 0 && path
->p_ext
== NULL
)
1317 return EXT_MAX_BLOCK
;
1319 while (depth
>= 0) {
1320 if (depth
== path
->p_depth
) {
1322 if (path
[depth
].p_ext
!=
1323 EXT_LAST_EXTENT(path
[depth
].p_hdr
))
1324 return le32_to_cpu(path
[depth
].p_ext
[1].ee_block
);
1327 if (path
[depth
].p_idx
!=
1328 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1329 return le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1334 return EXT_MAX_BLOCK
;
1338 * ext4_ext_next_leaf_block:
1339 * returns first allocated block from next leaf or EXT_MAX_BLOCK
1341 static ext4_lblk_t
ext4_ext_next_leaf_block(struct inode
*inode
,
1342 struct ext4_ext_path
*path
)
1346 BUG_ON(path
== NULL
);
1347 depth
= path
->p_depth
;
1349 /* zero-tree has no leaf blocks at all */
1351 return EXT_MAX_BLOCK
;
1353 /* go to index block */
1356 while (depth
>= 0) {
1357 if (path
[depth
].p_idx
!=
1358 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1359 return (ext4_lblk_t
)
1360 le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1364 return EXT_MAX_BLOCK
;
1368 * ext4_ext_correct_indexes:
1369 * if leaf gets modified and modified extent is first in the leaf,
1370 * then we have to correct all indexes above.
1371 * TODO: do we need to correct tree in all cases?
1373 static int ext4_ext_correct_indexes(handle_t
*handle
, struct inode
*inode
,
1374 struct ext4_ext_path
*path
)
1376 struct ext4_extent_header
*eh
;
1377 int depth
= ext_depth(inode
);
1378 struct ext4_extent
*ex
;
1382 eh
= path
[depth
].p_hdr
;
1383 ex
= path
[depth
].p_ext
;
1388 /* there is no tree at all */
1392 if (ex
!= EXT_FIRST_EXTENT(eh
)) {
1393 /* we correct tree if first leaf got modified only */
1398 * TODO: we need correction if border is smaller than current one
1401 border
= path
[depth
].p_ext
->ee_block
;
1402 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1405 path
[k
].p_idx
->ei_block
= border
;
1406 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1411 /* change all left-side indexes */
1412 if (path
[k
+1].p_idx
!= EXT_FIRST_INDEX(path
[k
+1].p_hdr
))
1414 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1417 path
[k
].p_idx
->ei_block
= border
;
1418 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1427 ext4_can_extents_be_merged(struct inode
*inode
, struct ext4_extent
*ex1
,
1428 struct ext4_extent
*ex2
)
1430 unsigned short ext1_ee_len
, ext2_ee_len
, max_len
;
1433 * Make sure that either both extents are uninitialized, or
1436 if (ext4_ext_is_uninitialized(ex1
) ^ ext4_ext_is_uninitialized(ex2
))
1439 if (ext4_ext_is_uninitialized(ex1
))
1440 max_len
= EXT_UNINIT_MAX_LEN
;
1442 max_len
= EXT_INIT_MAX_LEN
;
1444 ext1_ee_len
= ext4_ext_get_actual_len(ex1
);
1445 ext2_ee_len
= ext4_ext_get_actual_len(ex2
);
1447 if (le32_to_cpu(ex1
->ee_block
) + ext1_ee_len
!=
1448 le32_to_cpu(ex2
->ee_block
))
1452 * To allow future support for preallocated extents to be added
1453 * as an RO_COMPAT feature, refuse to merge to extents if
1454 * this can result in the top bit of ee_len being set.
1456 if (ext1_ee_len
+ ext2_ee_len
> max_len
)
1458 #ifdef AGGRESSIVE_TEST
1459 if (ext1_ee_len
>= 4)
1463 if (ext_pblock(ex1
) + ext1_ee_len
== ext_pblock(ex2
))
1469 * This function tries to merge the "ex" extent to the next extent in the tree.
1470 * It always tries to merge towards right. If you want to merge towards
1471 * left, pass "ex - 1" as argument instead of "ex".
1472 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1473 * 1 if they got merged.
1475 int ext4_ext_try_to_merge(struct inode
*inode
,
1476 struct ext4_ext_path
*path
,
1477 struct ext4_extent
*ex
)
1479 struct ext4_extent_header
*eh
;
1480 unsigned int depth
, len
;
1482 int uninitialized
= 0;
1484 depth
= ext_depth(inode
);
1485 BUG_ON(path
[depth
].p_hdr
== NULL
);
1486 eh
= path
[depth
].p_hdr
;
1488 while (ex
< EXT_LAST_EXTENT(eh
)) {
1489 if (!ext4_can_extents_be_merged(inode
, ex
, ex
+ 1))
1491 /* merge with next extent! */
1492 if (ext4_ext_is_uninitialized(ex
))
1494 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1495 + ext4_ext_get_actual_len(ex
+ 1));
1497 ext4_ext_mark_uninitialized(ex
);
1499 if (ex
+ 1 < EXT_LAST_EXTENT(eh
)) {
1500 len
= (EXT_LAST_EXTENT(eh
) - ex
- 1)
1501 * sizeof(struct ext4_extent
);
1502 memmove(ex
+ 1, ex
+ 2, len
);
1504 le16_add_cpu(&eh
->eh_entries
, -1);
1506 WARN_ON(eh
->eh_entries
== 0);
1507 if (!eh
->eh_entries
)
1508 ext4_error(inode
->i_sb
, "ext4_ext_try_to_merge",
1509 "inode#%lu, eh->eh_entries = 0!", inode
->i_ino
);
1516 * check if a portion of the "newext" extent overlaps with an
1519 * If there is an overlap discovered, it updates the length of the newext
1520 * such that there will be no overlap, and then returns 1.
1521 * If there is no overlap found, it returns 0.
1523 unsigned int ext4_ext_check_overlap(struct inode
*inode
,
1524 struct ext4_extent
*newext
,
1525 struct ext4_ext_path
*path
)
1528 unsigned int depth
, len1
;
1529 unsigned int ret
= 0;
1531 b1
= le32_to_cpu(newext
->ee_block
);
1532 len1
= ext4_ext_get_actual_len(newext
);
1533 depth
= ext_depth(inode
);
1534 if (!path
[depth
].p_ext
)
1536 b2
= le32_to_cpu(path
[depth
].p_ext
->ee_block
);
1539 * get the next allocated block if the extent in the path
1540 * is before the requested block(s)
1543 b2
= ext4_ext_next_allocated_block(path
);
1544 if (b2
== EXT_MAX_BLOCK
)
1548 /* check for wrap through zero on extent logical start block*/
1549 if (b1
+ len1
< b1
) {
1550 len1
= EXT_MAX_BLOCK
- b1
;
1551 newext
->ee_len
= cpu_to_le16(len1
);
1555 /* check for overlap */
1556 if (b1
+ len1
> b2
) {
1557 newext
->ee_len
= cpu_to_le16(b2
- b1
);
1565 * ext4_ext_insert_extent:
1566 * tries to merge requsted extent into the existing extent or
1567 * inserts requested extent as new one into the tree,
1568 * creating new leaf in the no-space case.
1570 int ext4_ext_insert_extent(handle_t
*handle
, struct inode
*inode
,
1571 struct ext4_ext_path
*path
,
1572 struct ext4_extent
*newext
)
1574 struct ext4_extent_header
*eh
;
1575 struct ext4_extent
*ex
, *fex
;
1576 struct ext4_extent
*nearex
; /* nearest extent */
1577 struct ext4_ext_path
*npath
= NULL
;
1578 int depth
, len
, err
;
1580 unsigned uninitialized
= 0;
1582 BUG_ON(ext4_ext_get_actual_len(newext
) == 0);
1583 depth
= ext_depth(inode
);
1584 ex
= path
[depth
].p_ext
;
1585 BUG_ON(path
[depth
].p_hdr
== NULL
);
1587 /* try to insert block into found extent and return */
1588 if (ex
&& ext4_can_extents_be_merged(inode
, ex
, newext
)) {
1589 ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
1590 ext4_ext_is_uninitialized(newext
),
1591 ext4_ext_get_actual_len(newext
),
1592 le32_to_cpu(ex
->ee_block
),
1593 ext4_ext_is_uninitialized(ex
),
1594 ext4_ext_get_actual_len(ex
), ext_pblock(ex
));
1595 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
1600 * ext4_can_extents_be_merged should have checked that either
1601 * both extents are uninitialized, or both aren't. Thus we
1602 * need to check only one of them here.
1604 if (ext4_ext_is_uninitialized(ex
))
1606 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1607 + ext4_ext_get_actual_len(newext
));
1609 ext4_ext_mark_uninitialized(ex
);
1610 eh
= path
[depth
].p_hdr
;
1616 depth
= ext_depth(inode
);
1617 eh
= path
[depth
].p_hdr
;
1618 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
))
1621 /* probably next leaf has space for us? */
1622 fex
= EXT_LAST_EXTENT(eh
);
1623 next
= ext4_ext_next_leaf_block(inode
, path
);
1624 if (le32_to_cpu(newext
->ee_block
) > le32_to_cpu(fex
->ee_block
)
1625 && next
!= EXT_MAX_BLOCK
) {
1626 ext_debug("next leaf block - %d\n", next
);
1627 BUG_ON(npath
!= NULL
);
1628 npath
= ext4_ext_find_extent(inode
, next
, NULL
);
1630 return PTR_ERR(npath
);
1631 BUG_ON(npath
->p_depth
!= path
->p_depth
);
1632 eh
= npath
[depth
].p_hdr
;
1633 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
)) {
1634 ext_debug("next leaf isnt full(%d)\n",
1635 le16_to_cpu(eh
->eh_entries
));
1639 ext_debug("next leaf has no free space(%d,%d)\n",
1640 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
1644 * There is no free space in the found leaf.
1645 * We're gonna add a new leaf in the tree.
1647 err
= ext4_ext_create_new_leaf(handle
, inode
, path
, newext
);
1650 depth
= ext_depth(inode
);
1651 eh
= path
[depth
].p_hdr
;
1654 nearex
= path
[depth
].p_ext
;
1656 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
1661 /* there is no extent in this leaf, create first one */
1662 ext_debug("first extent in the leaf: %d:%llu:[%d]%d\n",
1663 le32_to_cpu(newext
->ee_block
),
1665 ext4_ext_is_uninitialized(newext
),
1666 ext4_ext_get_actual_len(newext
));
1667 path
[depth
].p_ext
= EXT_FIRST_EXTENT(eh
);
1668 } else if (le32_to_cpu(newext
->ee_block
)
1669 > le32_to_cpu(nearex
->ee_block
)) {
1670 /* BUG_ON(newext->ee_block == nearex->ee_block); */
1671 if (nearex
!= EXT_LAST_EXTENT(eh
)) {
1672 len
= EXT_MAX_EXTENT(eh
) - nearex
;
1673 len
= (len
- 1) * sizeof(struct ext4_extent
);
1674 len
= len
< 0 ? 0 : len
;
1675 ext_debug("insert %d:%llu:[%d]%d after: nearest 0x%p, "
1676 "move %d from 0x%p to 0x%p\n",
1677 le32_to_cpu(newext
->ee_block
),
1679 ext4_ext_is_uninitialized(newext
),
1680 ext4_ext_get_actual_len(newext
),
1681 nearex
, len
, nearex
+ 1, nearex
+ 2);
1682 memmove(nearex
+ 2, nearex
+ 1, len
);
1684 path
[depth
].p_ext
= nearex
+ 1;
1686 BUG_ON(newext
->ee_block
== nearex
->ee_block
);
1687 len
= (EXT_MAX_EXTENT(eh
) - nearex
) * sizeof(struct ext4_extent
);
1688 len
= len
< 0 ? 0 : len
;
1689 ext_debug("insert %d:%llu:[%d]%d before: nearest 0x%p, "
1690 "move %d from 0x%p to 0x%p\n",
1691 le32_to_cpu(newext
->ee_block
),
1693 ext4_ext_is_uninitialized(newext
),
1694 ext4_ext_get_actual_len(newext
),
1695 nearex
, len
, nearex
+ 1, nearex
+ 2);
1696 memmove(nearex
+ 1, nearex
, len
);
1697 path
[depth
].p_ext
= nearex
;
1700 le16_add_cpu(&eh
->eh_entries
, 1);
1701 nearex
= path
[depth
].p_ext
;
1702 nearex
->ee_block
= newext
->ee_block
;
1703 ext4_ext_store_pblock(nearex
, ext_pblock(newext
));
1704 nearex
->ee_len
= newext
->ee_len
;
1707 /* try to merge extents to the right */
1708 ext4_ext_try_to_merge(inode
, path
, nearex
);
1710 /* try to merge extents to the left */
1712 /* time to correct all indexes above */
1713 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
1717 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
1721 ext4_ext_drop_refs(npath
);
1724 ext4_ext_invalidate_cache(inode
);
1728 int ext4_ext_walk_space(struct inode
*inode
, ext4_lblk_t block
,
1729 ext4_lblk_t num
, ext_prepare_callback func
,
1732 struct ext4_ext_path
*path
= NULL
;
1733 struct ext4_ext_cache cbex
;
1734 struct ext4_extent
*ex
;
1735 ext4_lblk_t next
, start
= 0, end
= 0;
1736 ext4_lblk_t last
= block
+ num
;
1737 int depth
, exists
, err
= 0;
1739 BUG_ON(func
== NULL
);
1740 BUG_ON(inode
== NULL
);
1742 while (block
< last
&& block
!= EXT_MAX_BLOCK
) {
1744 /* find extent for this block */
1745 path
= ext4_ext_find_extent(inode
, block
, path
);
1747 err
= PTR_ERR(path
);
1752 depth
= ext_depth(inode
);
1753 BUG_ON(path
[depth
].p_hdr
== NULL
);
1754 ex
= path
[depth
].p_ext
;
1755 next
= ext4_ext_next_allocated_block(path
);
1759 /* there is no extent yet, so try to allocate
1760 * all requested space */
1763 } else if (le32_to_cpu(ex
->ee_block
) > block
) {
1764 /* need to allocate space before found extent */
1766 end
= le32_to_cpu(ex
->ee_block
);
1767 if (block
+ num
< end
)
1769 } else if (block
>= le32_to_cpu(ex
->ee_block
)
1770 + ext4_ext_get_actual_len(ex
)) {
1771 /* need to allocate space after found extent */
1776 } else if (block
>= le32_to_cpu(ex
->ee_block
)) {
1778 * some part of requested space is covered
1782 end
= le32_to_cpu(ex
->ee_block
)
1783 + ext4_ext_get_actual_len(ex
);
1784 if (block
+ num
< end
)
1790 BUG_ON(end
<= start
);
1793 cbex
.ec_block
= start
;
1794 cbex
.ec_len
= end
- start
;
1796 cbex
.ec_type
= EXT4_EXT_CACHE_GAP
;
1798 cbex
.ec_block
= le32_to_cpu(ex
->ee_block
);
1799 cbex
.ec_len
= ext4_ext_get_actual_len(ex
);
1800 cbex
.ec_start
= ext_pblock(ex
);
1801 cbex
.ec_type
= EXT4_EXT_CACHE_EXTENT
;
1804 BUG_ON(cbex
.ec_len
== 0);
1805 err
= func(inode
, path
, &cbex
, ex
, cbdata
);
1806 ext4_ext_drop_refs(path
);
1811 if (err
== EXT_REPEAT
)
1813 else if (err
== EXT_BREAK
) {
1818 if (ext_depth(inode
) != depth
) {
1819 /* depth was changed. we have to realloc path */
1824 block
= cbex
.ec_block
+ cbex
.ec_len
;
1828 ext4_ext_drop_refs(path
);
1836 ext4_ext_put_in_cache(struct inode
*inode
, ext4_lblk_t block
,
1837 __u32 len
, ext4_fsblk_t start
, int type
)
1839 struct ext4_ext_cache
*cex
;
1841 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1842 cex
= &EXT4_I(inode
)->i_cached_extent
;
1843 cex
->ec_type
= type
;
1844 cex
->ec_block
= block
;
1846 cex
->ec_start
= start
;
1847 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1851 * ext4_ext_put_gap_in_cache:
1852 * calculate boundaries of the gap that the requested block fits into
1853 * and cache this gap
1856 ext4_ext_put_gap_in_cache(struct inode
*inode
, struct ext4_ext_path
*path
,
1859 int depth
= ext_depth(inode
);
1862 struct ext4_extent
*ex
;
1864 ex
= path
[depth
].p_ext
;
1866 /* there is no extent yet, so gap is [0;-] */
1868 len
= EXT_MAX_BLOCK
;
1869 ext_debug("cache gap(whole file):");
1870 } else if (block
< le32_to_cpu(ex
->ee_block
)) {
1872 len
= le32_to_cpu(ex
->ee_block
) - block
;
1873 ext_debug("cache gap(before): %u [%u:%u]",
1875 le32_to_cpu(ex
->ee_block
),
1876 ext4_ext_get_actual_len(ex
));
1877 } else if (block
>= le32_to_cpu(ex
->ee_block
)
1878 + ext4_ext_get_actual_len(ex
)) {
1880 lblock
= le32_to_cpu(ex
->ee_block
)
1881 + ext4_ext_get_actual_len(ex
);
1883 next
= ext4_ext_next_allocated_block(path
);
1884 ext_debug("cache gap(after): [%u:%u] %u",
1885 le32_to_cpu(ex
->ee_block
),
1886 ext4_ext_get_actual_len(ex
),
1888 BUG_ON(next
== lblock
);
1889 len
= next
- lblock
;
1895 ext_debug(" -> %u:%lu\n", lblock
, len
);
1896 ext4_ext_put_in_cache(inode
, lblock
, len
, 0, EXT4_EXT_CACHE_GAP
);
1900 ext4_ext_in_cache(struct inode
*inode
, ext4_lblk_t block
,
1901 struct ext4_extent
*ex
)
1903 struct ext4_ext_cache
*cex
;
1904 int ret
= EXT4_EXT_CACHE_NO
;
1907 * We borrow i_block_reservation_lock to protect i_cached_extent
1909 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1910 cex
= &EXT4_I(inode
)->i_cached_extent
;
1912 /* has cache valid data? */
1913 if (cex
->ec_type
== EXT4_EXT_CACHE_NO
)
1916 BUG_ON(cex
->ec_type
!= EXT4_EXT_CACHE_GAP
&&
1917 cex
->ec_type
!= EXT4_EXT_CACHE_EXTENT
);
1918 if (block
>= cex
->ec_block
&& block
< cex
->ec_block
+ cex
->ec_len
) {
1919 ex
->ee_block
= cpu_to_le32(cex
->ec_block
);
1920 ext4_ext_store_pblock(ex
, cex
->ec_start
);
1921 ex
->ee_len
= cpu_to_le16(cex
->ec_len
);
1922 ext_debug("%u cached by %u:%u:%llu\n",
1924 cex
->ec_block
, cex
->ec_len
, cex
->ec_start
);
1928 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1934 * removes index from the index block.
1935 * It's used in truncate case only, thus all requests are for
1936 * last index in the block only.
1938 static int ext4_ext_rm_idx(handle_t
*handle
, struct inode
*inode
,
1939 struct ext4_ext_path
*path
)
1941 struct buffer_head
*bh
;
1945 /* free index block */
1947 leaf
= idx_pblock(path
->p_idx
);
1948 BUG_ON(path
->p_hdr
->eh_entries
== 0);
1949 err
= ext4_ext_get_access(handle
, inode
, path
);
1952 le16_add_cpu(&path
->p_hdr
->eh_entries
, -1);
1953 err
= ext4_ext_dirty(handle
, inode
, path
);
1956 ext_debug("index is empty, remove it, free block %llu\n", leaf
);
1957 bh
= sb_find_get_block(inode
->i_sb
, leaf
);
1958 ext4_forget(handle
, 1, inode
, bh
, leaf
);
1959 ext4_free_blocks(handle
, inode
, leaf
, 1, 1);
1964 * ext4_ext_calc_credits_for_single_extent:
1965 * This routine returns max. credits that needed to insert an extent
1966 * to the extent tree.
1967 * When pass the actual path, the caller should calculate credits
1970 int ext4_ext_calc_credits_for_single_extent(struct inode
*inode
, int nrblocks
,
1971 struct ext4_ext_path
*path
)
1974 int depth
= ext_depth(inode
);
1977 /* probably there is space in leaf? */
1978 if (le16_to_cpu(path
[depth
].p_hdr
->eh_entries
)
1979 < le16_to_cpu(path
[depth
].p_hdr
->eh_max
)) {
1982 * There are some space in the leaf tree, no
1983 * need to account for leaf block credit
1985 * bitmaps and block group descriptor blocks
1986 * and other metadat blocks still need to be
1989 /* 1 bitmap, 1 block group descriptor */
1990 ret
= 2 + EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
1995 return ext4_chunk_trans_blocks(inode
, nrblocks
);
1999 * How many index/leaf blocks need to change/allocate to modify nrblocks?
2001 * if nrblocks are fit in a single extent (chunk flag is 1), then
2002 * in the worse case, each tree level index/leaf need to be changed
2003 * if the tree split due to insert a new extent, then the old tree
2004 * index/leaf need to be updated too
2006 * If the nrblocks are discontiguous, they could cause
2007 * the whole tree split more than once, but this is really rare.
2009 int ext4_ext_index_trans_blocks(struct inode
*inode
, int nrblocks
, int chunk
)
2012 int depth
= ext_depth(inode
);
2022 static int ext4_remove_blocks(handle_t
*handle
, struct inode
*inode
,
2023 struct ext4_extent
*ex
,
2024 ext4_lblk_t from
, ext4_lblk_t to
)
2026 struct buffer_head
*bh
;
2027 unsigned short ee_len
= ext4_ext_get_actual_len(ex
);
2028 int i
, metadata
= 0;
2030 if (S_ISDIR(inode
->i_mode
) || S_ISLNK(inode
->i_mode
))
2032 #ifdef EXTENTS_STATS
2034 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2035 spin_lock(&sbi
->s_ext_stats_lock
);
2036 sbi
->s_ext_blocks
+= ee_len
;
2037 sbi
->s_ext_extents
++;
2038 if (ee_len
< sbi
->s_ext_min
)
2039 sbi
->s_ext_min
= ee_len
;
2040 if (ee_len
> sbi
->s_ext_max
)
2041 sbi
->s_ext_max
= ee_len
;
2042 if (ext_depth(inode
) > sbi
->s_depth_max
)
2043 sbi
->s_depth_max
= ext_depth(inode
);
2044 spin_unlock(&sbi
->s_ext_stats_lock
);
2047 if (from
>= le32_to_cpu(ex
->ee_block
)
2048 && to
== le32_to_cpu(ex
->ee_block
) + ee_len
- 1) {
2053 num
= le32_to_cpu(ex
->ee_block
) + ee_len
- from
;
2054 start
= ext_pblock(ex
) + ee_len
- num
;
2055 ext_debug("free last %u blocks starting %llu\n", num
, start
);
2056 for (i
= 0; i
< num
; i
++) {
2057 bh
= sb_find_get_block(inode
->i_sb
, start
+ i
);
2058 ext4_forget(handle
, 0, inode
, bh
, start
+ i
);
2060 ext4_free_blocks(handle
, inode
, start
, num
, metadata
);
2061 } else if (from
== le32_to_cpu(ex
->ee_block
)
2062 && to
<= le32_to_cpu(ex
->ee_block
) + ee_len
- 1) {
2063 printk(KERN_INFO
"strange request: removal %u-%u from %u:%u\n",
2064 from
, to
, le32_to_cpu(ex
->ee_block
), ee_len
);
2066 printk(KERN_INFO
"strange request: removal(2) "
2067 "%u-%u from %u:%u\n",
2068 from
, to
, le32_to_cpu(ex
->ee_block
), ee_len
);
2074 ext4_ext_rm_leaf(handle_t
*handle
, struct inode
*inode
,
2075 struct ext4_ext_path
*path
, ext4_lblk_t start
)
2077 int err
= 0, correct_index
= 0;
2078 int depth
= ext_depth(inode
), credits
;
2079 struct ext4_extent_header
*eh
;
2080 ext4_lblk_t a
, b
, block
;
2082 ext4_lblk_t ex_ee_block
;
2083 unsigned short ex_ee_len
;
2084 unsigned uninitialized
= 0;
2085 struct ext4_extent
*ex
;
2087 /* the header must be checked already in ext4_ext_remove_space() */
2088 ext_debug("truncate since %u in leaf\n", start
);
2089 if (!path
[depth
].p_hdr
)
2090 path
[depth
].p_hdr
= ext_block_hdr(path
[depth
].p_bh
);
2091 eh
= path
[depth
].p_hdr
;
2094 /* find where to start removing */
2095 ex
= EXT_LAST_EXTENT(eh
);
2097 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2098 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2100 while (ex
>= EXT_FIRST_EXTENT(eh
) &&
2101 ex_ee_block
+ ex_ee_len
> start
) {
2103 if (ext4_ext_is_uninitialized(ex
))
2108 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block
,
2109 uninitialized
, ex_ee_len
);
2110 path
[depth
].p_ext
= ex
;
2112 a
= ex_ee_block
> start
? ex_ee_block
: start
;
2113 b
= ex_ee_block
+ ex_ee_len
- 1 < EXT_MAX_BLOCK
?
2114 ex_ee_block
+ ex_ee_len
- 1 : EXT_MAX_BLOCK
;
2116 ext_debug(" border %u:%u\n", a
, b
);
2118 if (a
!= ex_ee_block
&& b
!= ex_ee_block
+ ex_ee_len
- 1) {
2122 } else if (a
!= ex_ee_block
) {
2123 /* remove tail of the extent */
2124 block
= ex_ee_block
;
2126 } else if (b
!= ex_ee_block
+ ex_ee_len
- 1) {
2127 /* remove head of the extent */
2130 /* there is no "make a hole" API yet */
2133 /* remove whole extent: excellent! */
2134 block
= ex_ee_block
;
2136 BUG_ON(a
!= ex_ee_block
);
2137 BUG_ON(b
!= ex_ee_block
+ ex_ee_len
- 1);
2141 * 3 for leaf, sb, and inode plus 2 (bmap and group
2142 * descriptor) for each block group; assume two block
2143 * groups plus ex_ee_len/blocks_per_block_group for
2146 credits
= 7 + 2*(ex_ee_len
/EXT4_BLOCKS_PER_GROUP(inode
->i_sb
));
2147 if (ex
== EXT_FIRST_EXTENT(eh
)) {
2149 credits
+= (ext_depth(inode
)) + 1;
2151 credits
+= 2 * EXT4_QUOTA_TRANS_BLOCKS(inode
->i_sb
);
2153 err
= ext4_ext_journal_restart(handle
, credits
);
2157 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2161 err
= ext4_remove_blocks(handle
, inode
, ex
, a
, b
);
2166 /* this extent is removed; mark slot entirely unused */
2167 ext4_ext_store_pblock(ex
, 0);
2168 le16_add_cpu(&eh
->eh_entries
, -1);
2171 ex
->ee_block
= cpu_to_le32(block
);
2172 ex
->ee_len
= cpu_to_le16(num
);
2174 * Do not mark uninitialized if all the blocks in the
2175 * extent have been removed.
2177 if (uninitialized
&& num
)
2178 ext4_ext_mark_uninitialized(ex
);
2180 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2184 ext_debug("new extent: %u:%u:%llu\n", block
, num
,
2187 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2188 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2191 if (correct_index
&& eh
->eh_entries
)
2192 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2194 /* if this leaf is free, then we should
2195 * remove it from index block above */
2196 if (err
== 0 && eh
->eh_entries
== 0 && path
[depth
].p_bh
!= NULL
)
2197 err
= ext4_ext_rm_idx(handle
, inode
, path
+ depth
);
2204 * ext4_ext_more_to_rm:
2205 * returns 1 if current index has to be freed (even partial)
2208 ext4_ext_more_to_rm(struct ext4_ext_path
*path
)
2210 BUG_ON(path
->p_idx
== NULL
);
2212 if (path
->p_idx
< EXT_FIRST_INDEX(path
->p_hdr
))
2216 * if truncate on deeper level happened, it wasn't partial,
2217 * so we have to consider current index for truncation
2219 if (le16_to_cpu(path
->p_hdr
->eh_entries
) == path
->p_block
)
2224 static int ext4_ext_remove_space(struct inode
*inode
, ext4_lblk_t start
)
2226 struct super_block
*sb
= inode
->i_sb
;
2227 int depth
= ext_depth(inode
);
2228 struct ext4_ext_path
*path
;
2232 ext_debug("truncate since %u\n", start
);
2234 /* probably first extent we're gonna free will be last in block */
2235 handle
= ext4_journal_start(inode
, depth
+ 1);
2237 return PTR_ERR(handle
);
2239 ext4_ext_invalidate_cache(inode
);
2242 * We start scanning from right side, freeing all the blocks
2243 * after i_size and walking into the tree depth-wise.
2245 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 1), GFP_NOFS
);
2247 ext4_journal_stop(handle
);
2250 path
[0].p_hdr
= ext_inode_hdr(inode
);
2251 if (ext4_ext_check(inode
, path
[0].p_hdr
, depth
)) {
2255 path
[0].p_depth
= depth
;
2257 while (i
>= 0 && err
== 0) {
2259 /* this is leaf block */
2260 err
= ext4_ext_rm_leaf(handle
, inode
, path
, start
);
2261 /* root level has p_bh == NULL, brelse() eats this */
2262 brelse(path
[i
].p_bh
);
2263 path
[i
].p_bh
= NULL
;
2268 /* this is index block */
2269 if (!path
[i
].p_hdr
) {
2270 ext_debug("initialize header\n");
2271 path
[i
].p_hdr
= ext_block_hdr(path
[i
].p_bh
);
2274 if (!path
[i
].p_idx
) {
2275 /* this level hasn't been touched yet */
2276 path
[i
].p_idx
= EXT_LAST_INDEX(path
[i
].p_hdr
);
2277 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
)+1;
2278 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2280 le16_to_cpu(path
[i
].p_hdr
->eh_entries
));
2282 /* we were already here, see at next index */
2286 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2287 i
, EXT_FIRST_INDEX(path
[i
].p_hdr
),
2289 if (ext4_ext_more_to_rm(path
+ i
)) {
2290 struct buffer_head
*bh
;
2291 /* go to the next level */
2292 ext_debug("move to level %d (block %llu)\n",
2293 i
+ 1, idx_pblock(path
[i
].p_idx
));
2294 memset(path
+ i
+ 1, 0, sizeof(*path
));
2295 bh
= sb_bread(sb
, idx_pblock(path
[i
].p_idx
));
2297 /* should we reset i_size? */
2301 if (WARN_ON(i
+ 1 > depth
)) {
2305 if (ext4_ext_check(inode
, ext_block_hdr(bh
),
2310 path
[i
+ 1].p_bh
= bh
;
2312 /* save actual number of indexes since this
2313 * number is changed at the next iteration */
2314 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
);
2317 /* we finished processing this index, go up */
2318 if (path
[i
].p_hdr
->eh_entries
== 0 && i
> 0) {
2319 /* index is empty, remove it;
2320 * handle must be already prepared by the
2321 * truncatei_leaf() */
2322 err
= ext4_ext_rm_idx(handle
, inode
, path
+ i
);
2324 /* root level has p_bh == NULL, brelse() eats this */
2325 brelse(path
[i
].p_bh
);
2326 path
[i
].p_bh
= NULL
;
2328 ext_debug("return to level %d\n", i
);
2332 /* TODO: flexible tree reduction should be here */
2333 if (path
->p_hdr
->eh_entries
== 0) {
2335 * truncate to zero freed all the tree,
2336 * so we need to correct eh_depth
2338 err
= ext4_ext_get_access(handle
, inode
, path
);
2340 ext_inode_hdr(inode
)->eh_depth
= 0;
2341 ext_inode_hdr(inode
)->eh_max
=
2342 cpu_to_le16(ext4_ext_space_root(inode
));
2343 err
= ext4_ext_dirty(handle
, inode
, path
);
2347 ext4_ext_drop_refs(path
);
2349 ext4_journal_stop(handle
);
2355 * called at mount time
2357 void ext4_ext_init(struct super_block
*sb
)
2360 * possible initialization would be here
2363 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
)) {
2364 printk(KERN_INFO
"EXT4-fs: file extents enabled");
2365 #ifdef AGGRESSIVE_TEST
2366 printk(", aggressive tests");
2368 #ifdef CHECK_BINSEARCH
2369 printk(", check binsearch");
2371 #ifdef EXTENTS_STATS
2375 #ifdef EXTENTS_STATS
2376 spin_lock_init(&EXT4_SB(sb
)->s_ext_stats_lock
);
2377 EXT4_SB(sb
)->s_ext_min
= 1 << 30;
2378 EXT4_SB(sb
)->s_ext_max
= 0;
2384 * called at umount time
2386 void ext4_ext_release(struct super_block
*sb
)
2388 if (!EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
))
2391 #ifdef EXTENTS_STATS
2392 if (EXT4_SB(sb
)->s_ext_blocks
&& EXT4_SB(sb
)->s_ext_extents
) {
2393 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2394 printk(KERN_ERR
"EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2395 sbi
->s_ext_blocks
, sbi
->s_ext_extents
,
2396 sbi
->s_ext_blocks
/ sbi
->s_ext_extents
);
2397 printk(KERN_ERR
"EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2398 sbi
->s_ext_min
, sbi
->s_ext_max
, sbi
->s_depth_max
);
2403 static void bi_complete(struct bio
*bio
, int error
)
2405 complete((struct completion
*)bio
->bi_private
);
2408 /* FIXME!! we need to try to merge to left or right after zero-out */
2409 static int ext4_ext_zeroout(struct inode
*inode
, struct ext4_extent
*ex
)
2413 int blkbits
, blocksize
;
2415 struct completion event
;
2416 unsigned int ee_len
, len
, done
, offset
;
2419 blkbits
= inode
->i_blkbits
;
2420 blocksize
= inode
->i_sb
->s_blocksize
;
2421 ee_len
= ext4_ext_get_actual_len(ex
);
2422 ee_pblock
= ext_pblock(ex
);
2424 /* convert ee_pblock to 512 byte sectors */
2425 ee_pblock
= ee_pblock
<< (blkbits
- 9);
2427 while (ee_len
> 0) {
2429 if (ee_len
> BIO_MAX_PAGES
)
2430 len
= BIO_MAX_PAGES
;
2434 bio
= bio_alloc(GFP_NOIO
, len
);
2435 bio
->bi_sector
= ee_pblock
;
2436 bio
->bi_bdev
= inode
->i_sb
->s_bdev
;
2440 while (done
< len
) {
2441 ret
= bio_add_page(bio
, ZERO_PAGE(0),
2443 if (ret
!= blocksize
) {
2445 * We can't add any more pages because of
2446 * hardware limitations. Start a new bio.
2451 offset
+= blocksize
;
2452 if (offset
>= PAGE_CACHE_SIZE
)
2456 init_completion(&event
);
2457 bio
->bi_private
= &event
;
2458 bio
->bi_end_io
= bi_complete
;
2459 submit_bio(WRITE
, bio
);
2460 wait_for_completion(&event
);
2462 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
2470 ee_pblock
+= done
<< (blkbits
- 9);
2475 #define EXT4_EXT_ZERO_LEN 7
2478 * This function is called by ext4_ext_get_blocks() if someone tries to write
2479 * to an uninitialized extent. It may result in splitting the uninitialized
2480 * extent into multiple extents (upto three - one initialized and two
2482 * There are three possibilities:
2483 * a> There is no split required: Entire extent should be initialized
2484 * b> Splits in two extents: Write is happening at either end of the extent
2485 * c> Splits in three extents: Somone is writing in middle of the extent
2487 static int ext4_ext_convert_to_initialized(handle_t
*handle
,
2488 struct inode
*inode
,
2489 struct ext4_ext_path
*path
,
2491 unsigned int max_blocks
)
2493 struct ext4_extent
*ex
, newex
, orig_ex
;
2494 struct ext4_extent
*ex1
= NULL
;
2495 struct ext4_extent
*ex2
= NULL
;
2496 struct ext4_extent
*ex3
= NULL
;
2497 struct ext4_extent_header
*eh
;
2498 ext4_lblk_t ee_block
;
2499 unsigned int allocated
, ee_len
, depth
;
2500 ext4_fsblk_t newblock
;
2504 depth
= ext_depth(inode
);
2505 eh
= path
[depth
].p_hdr
;
2506 ex
= path
[depth
].p_ext
;
2507 ee_block
= le32_to_cpu(ex
->ee_block
);
2508 ee_len
= ext4_ext_get_actual_len(ex
);
2509 allocated
= ee_len
- (iblock
- ee_block
);
2510 newblock
= iblock
- ee_block
+ ext_pblock(ex
);
2512 orig_ex
.ee_block
= ex
->ee_block
;
2513 orig_ex
.ee_len
= cpu_to_le16(ee_len
);
2514 ext4_ext_store_pblock(&orig_ex
, ext_pblock(ex
));
2516 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2519 /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
2520 if (ee_len
<= 2*EXT4_EXT_ZERO_LEN
) {
2521 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2523 goto fix_extent_len
;
2524 /* update the extent length and mark as initialized */
2525 ex
->ee_block
= orig_ex
.ee_block
;
2526 ex
->ee_len
= orig_ex
.ee_len
;
2527 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2528 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2529 /* zeroed the full extent */
2533 /* ex1: ee_block to iblock - 1 : uninitialized */
2534 if (iblock
> ee_block
) {
2536 ex1
->ee_len
= cpu_to_le16(iblock
- ee_block
);
2537 ext4_ext_mark_uninitialized(ex1
);
2541 * for sanity, update the length of the ex2 extent before
2542 * we insert ex3, if ex1 is NULL. This is to avoid temporary
2543 * overlap of blocks.
2545 if (!ex1
&& allocated
> max_blocks
)
2546 ex2
->ee_len
= cpu_to_le16(max_blocks
);
2547 /* ex3: to ee_block + ee_len : uninitialised */
2548 if (allocated
> max_blocks
) {
2549 unsigned int newdepth
;
2550 /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */
2551 if (allocated
<= EXT4_EXT_ZERO_LEN
) {
2553 * iblock == ee_block is handled by the zerouout
2555 * Mark first half uninitialized.
2556 * Mark second half initialized and zero out the
2557 * initialized extent
2559 ex
->ee_block
= orig_ex
.ee_block
;
2560 ex
->ee_len
= cpu_to_le16(ee_len
- allocated
);
2561 ext4_ext_mark_uninitialized(ex
);
2562 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2563 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2566 ex3
->ee_block
= cpu_to_le32(iblock
);
2567 ext4_ext_store_pblock(ex3
, newblock
);
2568 ex3
->ee_len
= cpu_to_le16(allocated
);
2569 err
= ext4_ext_insert_extent(handle
, inode
, path
, ex3
);
2570 if (err
== -ENOSPC
) {
2571 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2573 goto fix_extent_len
;
2574 ex
->ee_block
= orig_ex
.ee_block
;
2575 ex
->ee_len
= orig_ex
.ee_len
;
2576 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2577 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2578 /* blocks available from iblock */
2582 goto fix_extent_len
;
2585 * We need to zero out the second half because
2586 * an fallocate request can update file size and
2587 * converting the second half to initialized extent
2588 * implies that we can leak some junk data to user
2591 err
= ext4_ext_zeroout(inode
, ex3
);
2594 * We should actually mark the
2595 * second half as uninit and return error
2596 * Insert would have changed the extent
2598 depth
= ext_depth(inode
);
2599 ext4_ext_drop_refs(path
);
2600 path
= ext4_ext_find_extent(inode
,
2603 err
= PTR_ERR(path
);
2606 /* get the second half extent details */
2607 ex
= path
[depth
].p_ext
;
2608 err
= ext4_ext_get_access(handle
, inode
,
2612 ext4_ext_mark_uninitialized(ex
);
2613 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2617 /* zeroed the second half */
2621 ex3
->ee_block
= cpu_to_le32(iblock
+ max_blocks
);
2622 ext4_ext_store_pblock(ex3
, newblock
+ max_blocks
);
2623 ex3
->ee_len
= cpu_to_le16(allocated
- max_blocks
);
2624 ext4_ext_mark_uninitialized(ex3
);
2625 err
= ext4_ext_insert_extent(handle
, inode
, path
, ex3
);
2626 if (err
== -ENOSPC
) {
2627 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2629 goto fix_extent_len
;
2630 /* update the extent length and mark as initialized */
2631 ex
->ee_block
= orig_ex
.ee_block
;
2632 ex
->ee_len
= orig_ex
.ee_len
;
2633 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2634 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2635 /* zeroed the full extent */
2636 /* blocks available from iblock */
2640 goto fix_extent_len
;
2642 * The depth, and hence eh & ex might change
2643 * as part of the insert above.
2645 newdepth
= ext_depth(inode
);
2647 * update the extent length after successful insert of the
2650 orig_ex
.ee_len
= cpu_to_le16(ee_len
-
2651 ext4_ext_get_actual_len(ex3
));
2653 ext4_ext_drop_refs(path
);
2654 path
= ext4_ext_find_extent(inode
, iblock
, path
);
2656 err
= PTR_ERR(path
);
2659 eh
= path
[depth
].p_hdr
;
2660 ex
= path
[depth
].p_ext
;
2664 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2668 allocated
= max_blocks
;
2670 /* If extent has less than EXT4_EXT_ZERO_LEN and we are trying
2671 * to insert a extent in the middle zerout directly
2672 * otherwise give the extent a chance to merge to left
2674 if (le16_to_cpu(orig_ex
.ee_len
) <= EXT4_EXT_ZERO_LEN
&&
2675 iblock
!= ee_block
) {
2676 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2678 goto fix_extent_len
;
2679 /* update the extent length and mark as initialized */
2680 ex
->ee_block
= orig_ex
.ee_block
;
2681 ex
->ee_len
= orig_ex
.ee_len
;
2682 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2683 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2684 /* zero out the first half */
2685 /* blocks available from iblock */
2690 * If there was a change of depth as part of the
2691 * insertion of ex3 above, we need to update the length
2692 * of the ex1 extent again here
2694 if (ex1
&& ex1
!= ex
) {
2696 ex1
->ee_len
= cpu_to_le16(iblock
- ee_block
);
2697 ext4_ext_mark_uninitialized(ex1
);
2700 /* ex2: iblock to iblock + maxblocks-1 : initialised */
2701 ex2
->ee_block
= cpu_to_le32(iblock
);
2702 ext4_ext_store_pblock(ex2
, newblock
);
2703 ex2
->ee_len
= cpu_to_le16(allocated
);
2707 * New (initialized) extent starts from the first block
2708 * in the current extent. i.e., ex2 == ex
2709 * We have to see if it can be merged with the extent
2712 if (ex2
> EXT_FIRST_EXTENT(eh
)) {
2714 * To merge left, pass "ex2 - 1" to try_to_merge(),
2715 * since it merges towards right _only_.
2717 ret
= ext4_ext_try_to_merge(inode
, path
, ex2
- 1);
2719 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2722 depth
= ext_depth(inode
);
2727 * Try to Merge towards right. This might be required
2728 * only when the whole extent is being written to.
2729 * i.e. ex2 == ex and ex3 == NULL.
2732 ret
= ext4_ext_try_to_merge(inode
, path
, ex2
);
2734 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2739 /* Mark modified extent as dirty */
2740 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2743 err
= ext4_ext_insert_extent(handle
, inode
, path
, &newex
);
2744 if (err
== -ENOSPC
) {
2745 err
= ext4_ext_zeroout(inode
, &orig_ex
);
2747 goto fix_extent_len
;
2748 /* update the extent length and mark as initialized */
2749 ex
->ee_block
= orig_ex
.ee_block
;
2750 ex
->ee_len
= orig_ex
.ee_len
;
2751 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2752 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2753 /* zero out the first half */
2756 goto fix_extent_len
;
2758 ext4_ext_show_leaf(inode
, path
);
2759 return err
? err
: allocated
;
2762 ex
->ee_block
= orig_ex
.ee_block
;
2763 ex
->ee_len
= orig_ex
.ee_len
;
2764 ext4_ext_store_pblock(ex
, ext_pblock(&orig_ex
));
2765 ext4_ext_mark_uninitialized(ex
);
2766 ext4_ext_dirty(handle
, inode
, path
+ depth
);
2771 * Block allocation/map/preallocation routine for extents based files
2774 * Need to be called with
2775 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
2776 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
2778 * return > 0, number of of blocks already mapped/allocated
2779 * if create == 0 and these are pre-allocated blocks
2780 * buffer head is unmapped
2781 * otherwise blocks are mapped
2783 * return = 0, if plain look up failed (blocks have not been allocated)
2784 * buffer head is unmapped
2786 * return < 0, error case.
2788 int ext4_ext_get_blocks(handle_t
*handle
, struct inode
*inode
,
2790 unsigned int max_blocks
, struct buffer_head
*bh_result
,
2793 struct ext4_ext_path
*path
= NULL
;
2794 struct ext4_extent_header
*eh
;
2795 struct ext4_extent newex
, *ex
;
2796 ext4_fsblk_t newblock
;
2797 int err
= 0, depth
, ret
, cache_type
;
2798 unsigned int allocated
= 0;
2799 struct ext4_allocation_request ar
;
2801 __clear_bit(BH_New
, &bh_result
->b_state
);
2802 ext_debug("blocks %u/%u requested for inode %lu\n",
2803 iblock
, max_blocks
, inode
->i_ino
);
2805 /* check in cache */
2806 cache_type
= ext4_ext_in_cache(inode
, iblock
, &newex
);
2808 if (cache_type
== EXT4_EXT_CACHE_GAP
) {
2809 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
2811 * block isn't allocated yet and
2812 * user doesn't want to allocate it
2816 /* we should allocate requested block */
2817 } else if (cache_type
== EXT4_EXT_CACHE_EXTENT
) {
2818 /* block is already allocated */
2820 - le32_to_cpu(newex
.ee_block
)
2821 + ext_pblock(&newex
);
2822 /* number of remaining blocks in the extent */
2823 allocated
= ext4_ext_get_actual_len(&newex
) -
2824 (iblock
- le32_to_cpu(newex
.ee_block
));
2831 /* find extent for this block */
2832 path
= ext4_ext_find_extent(inode
, iblock
, NULL
);
2834 err
= PTR_ERR(path
);
2839 depth
= ext_depth(inode
);
2842 * consistent leaf must not be empty;
2843 * this situation is possible, though, _during_ tree modification;
2844 * this is why assert can't be put in ext4_ext_find_extent()
2846 BUG_ON(path
[depth
].p_ext
== NULL
&& depth
!= 0);
2847 eh
= path
[depth
].p_hdr
;
2849 ex
= path
[depth
].p_ext
;
2851 ext4_lblk_t ee_block
= le32_to_cpu(ex
->ee_block
);
2852 ext4_fsblk_t ee_start
= ext_pblock(ex
);
2853 unsigned short ee_len
;
2856 * Uninitialized extents are treated as holes, except that
2857 * we split out initialized portions during a write.
2859 ee_len
= ext4_ext_get_actual_len(ex
);
2860 /* if found extent covers block, simply return it */
2861 if (iblock
>= ee_block
&& iblock
< ee_block
+ ee_len
) {
2862 newblock
= iblock
- ee_block
+ ee_start
;
2863 /* number of remaining blocks in the extent */
2864 allocated
= ee_len
- (iblock
- ee_block
);
2865 ext_debug("%u fit into %u:%d -> %llu\n", iblock
,
2866 ee_block
, ee_len
, newblock
);
2868 /* Do not put uninitialized extent in the cache */
2869 if (!ext4_ext_is_uninitialized(ex
)) {
2870 ext4_ext_put_in_cache(inode
, ee_block
,
2872 EXT4_EXT_CACHE_EXTENT
);
2875 if (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
)
2877 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
2878 if (allocated
> max_blocks
)
2879 allocated
= max_blocks
;
2881 * We have blocks reserved already. We
2882 * return allocated blocks so that delalloc
2883 * won't do block reservation for us. But
2884 * the buffer head will be unmapped so that
2885 * a read from the block returns 0s.
2887 set_buffer_unwritten(bh_result
);
2888 bh_result
->b_bdev
= inode
->i_sb
->s_bdev
;
2889 bh_result
->b_blocknr
= newblock
;
2893 ret
= ext4_ext_convert_to_initialized(handle
, inode
,
2906 * requested block isn't allocated yet;
2907 * we couldn't try to create block if create flag is zero
2909 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
2911 * put just found gap into cache to speed up
2912 * subsequent requests
2914 ext4_ext_put_gap_in_cache(inode
, path
, iblock
);
2918 * Okay, we need to do block allocation.
2921 /* find neighbour allocated blocks */
2923 err
= ext4_ext_search_left(inode
, path
, &ar
.lleft
, &ar
.pleft
);
2927 err
= ext4_ext_search_right(inode
, path
, &ar
.lright
, &ar
.pright
);
2932 * See if request is beyond maximum number of blocks we can have in
2933 * a single extent. For an initialized extent this limit is
2934 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
2935 * EXT_UNINIT_MAX_LEN.
2937 if (max_blocks
> EXT_INIT_MAX_LEN
&&
2938 !(flags
& EXT4_GET_BLOCKS_UNINIT_EXT
))
2939 max_blocks
= EXT_INIT_MAX_LEN
;
2940 else if (max_blocks
> EXT_UNINIT_MAX_LEN
&&
2941 (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
))
2942 max_blocks
= EXT_UNINIT_MAX_LEN
;
2944 /* Check if we can really insert (iblock)::(iblock+max_blocks) extent */
2945 newex
.ee_block
= cpu_to_le32(iblock
);
2946 newex
.ee_len
= cpu_to_le16(max_blocks
);
2947 err
= ext4_ext_check_overlap(inode
, &newex
, path
);
2949 allocated
= ext4_ext_get_actual_len(&newex
);
2951 allocated
= max_blocks
;
2953 /* allocate new block */
2955 ar
.goal
= ext4_ext_find_goal(inode
, path
, iblock
);
2956 ar
.logical
= iblock
;
2958 if (S_ISREG(inode
->i_mode
))
2959 ar
.flags
= EXT4_MB_HINT_DATA
;
2961 /* disable in-core preallocation for non-regular files */
2963 newblock
= ext4_mb_new_blocks(handle
, &ar
, &err
);
2966 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
2967 ar
.goal
, newblock
, allocated
);
2969 /* try to insert new extent into found leaf and return */
2970 ext4_ext_store_pblock(&newex
, newblock
);
2971 newex
.ee_len
= cpu_to_le16(ar
.len
);
2972 if (flags
& EXT4_GET_BLOCKS_UNINIT_EXT
) /* Mark uninitialized */
2973 ext4_ext_mark_uninitialized(&newex
);
2974 err
= ext4_ext_insert_extent(handle
, inode
, path
, &newex
);
2976 /* free data blocks we just allocated */
2977 /* not a good idea to call discard here directly,
2978 * but otherwise we'd need to call it every free() */
2979 ext4_discard_preallocations(inode
);
2980 ext4_free_blocks(handle
, inode
, ext_pblock(&newex
),
2981 ext4_ext_get_actual_len(&newex
), 0);
2985 /* previous routine could use block we allocated */
2986 newblock
= ext_pblock(&newex
);
2987 allocated
= ext4_ext_get_actual_len(&newex
);
2989 set_buffer_new(bh_result
);
2991 /* Cache only when it is _not_ an uninitialized extent */
2992 if ((flags
& EXT4_GET_BLOCKS_UNINIT_EXT
) == 0)
2993 ext4_ext_put_in_cache(inode
, iblock
, allocated
, newblock
,
2994 EXT4_EXT_CACHE_EXTENT
);
2996 if (allocated
> max_blocks
)
2997 allocated
= max_blocks
;
2998 ext4_ext_show_leaf(inode
, path
);
2999 set_buffer_mapped(bh_result
);
3000 bh_result
->b_bdev
= inode
->i_sb
->s_bdev
;
3001 bh_result
->b_blocknr
= newblock
;
3004 ext4_ext_drop_refs(path
);
3007 return err
? err
: allocated
;
3010 void ext4_ext_truncate(struct inode
*inode
)
3012 struct address_space
*mapping
= inode
->i_mapping
;
3013 struct super_block
*sb
= inode
->i_sb
;
3014 ext4_lblk_t last_block
;
3019 * probably first extent we're gonna free will be last in block
3021 err
= ext4_writepage_trans_blocks(inode
);
3022 handle
= ext4_journal_start(inode
, err
);
3026 if (inode
->i_size
& (sb
->s_blocksize
- 1))
3027 ext4_block_truncate_page(handle
, mapping
, inode
->i_size
);
3029 if (ext4_orphan_add(handle
, inode
))
3032 down_write(&EXT4_I(inode
)->i_data_sem
);
3033 ext4_ext_invalidate_cache(inode
);
3035 ext4_discard_preallocations(inode
);
3038 * TODO: optimization is possible here.
3039 * Probably we need not scan at all,
3040 * because page truncation is enough.
3043 /* we have to know where to truncate from in crash case */
3044 EXT4_I(inode
)->i_disksize
= inode
->i_size
;
3045 ext4_mark_inode_dirty(handle
, inode
);
3047 last_block
= (inode
->i_size
+ sb
->s_blocksize
- 1)
3048 >> EXT4_BLOCK_SIZE_BITS(sb
);
3049 err
= ext4_ext_remove_space(inode
, last_block
);
3051 /* In a multi-transaction truncate, we only make the final
3052 * transaction synchronous.
3055 ext4_handle_sync(handle
);
3058 up_write(&EXT4_I(inode
)->i_data_sem
);
3060 * If this was a simple ftruncate() and the file will remain alive,
3061 * then we need to clear up the orphan record which we created above.
3062 * However, if this was a real unlink then we were called by
3063 * ext4_delete_inode(), and we allow that function to clean up the
3064 * orphan info for us.
3067 ext4_orphan_del(handle
, inode
);
3069 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3070 ext4_mark_inode_dirty(handle
, inode
);
3071 ext4_journal_stop(handle
);
3074 static void ext4_falloc_update_inode(struct inode
*inode
,
3075 int mode
, loff_t new_size
, int update_ctime
)
3077 struct timespec now
;
3080 now
= current_fs_time(inode
->i_sb
);
3081 if (!timespec_equal(&inode
->i_ctime
, &now
))
3082 inode
->i_ctime
= now
;
3085 * Update only when preallocation was requested beyond
3088 if (!(mode
& FALLOC_FL_KEEP_SIZE
)) {
3089 if (new_size
> i_size_read(inode
))
3090 i_size_write(inode
, new_size
);
3091 if (new_size
> EXT4_I(inode
)->i_disksize
)
3092 ext4_update_i_disksize(inode
, new_size
);
3098 * preallocate space for a file. This implements ext4's fallocate inode
3099 * operation, which gets called from sys_fallocate system call.
3100 * For block-mapped files, posix_fallocate should fall back to the method
3101 * of writing zeroes to the required new blocks (the same behavior which is
3102 * expected for file systems which do not support fallocate() system call).
3104 long ext4_fallocate(struct inode
*inode
, int mode
, loff_t offset
, loff_t len
)
3109 unsigned int max_blocks
;
3113 struct buffer_head map_bh
;
3114 unsigned int credits
, blkbits
= inode
->i_blkbits
;
3117 * currently supporting (pre)allocate mode for extent-based
3120 if (!(EXT4_I(inode
)->i_flags
& EXT4_EXTENTS_FL
))
3123 /* preallocation to directories is currently not supported */
3124 if (S_ISDIR(inode
->i_mode
))
3127 block
= offset
>> blkbits
;
3129 * We can't just convert len to max_blocks because
3130 * If blocksize = 4096 offset = 3072 and len = 2048
3132 max_blocks
= (EXT4_BLOCK_ALIGN(len
+ offset
, blkbits
) >> blkbits
)
3135 * credits to insert 1 extent into extent tree
3137 credits
= ext4_chunk_trans_blocks(inode
, max_blocks
);
3138 mutex_lock(&inode
->i_mutex
);
3140 while (ret
>= 0 && ret
< max_blocks
) {
3141 block
= block
+ ret
;
3142 max_blocks
= max_blocks
- ret
;
3143 handle
= ext4_journal_start(inode
, credits
);
3144 if (IS_ERR(handle
)) {
3145 ret
= PTR_ERR(handle
);
3149 ret
= ext4_get_blocks(handle
, inode
, block
,
3150 max_blocks
, &map_bh
,
3151 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT
);
3155 printk(KERN_ERR
"%s: ext4_ext_get_blocks "
3156 "returned error inode#%lu, block=%u, "
3157 "max_blocks=%u", __func__
,
3158 inode
->i_ino
, block
, max_blocks
);
3160 ext4_mark_inode_dirty(handle
, inode
);
3161 ret2
= ext4_journal_stop(handle
);
3164 if ((block
+ ret
) >= (EXT4_BLOCK_ALIGN(offset
+ len
,
3165 blkbits
) >> blkbits
))
3166 new_size
= offset
+ len
;
3168 new_size
= (block
+ ret
) << blkbits
;
3170 ext4_falloc_update_inode(inode
, mode
, new_size
,
3171 buffer_new(&map_bh
));
3172 ext4_mark_inode_dirty(handle
, inode
);
3173 ret2
= ext4_journal_stop(handle
);
3177 if (ret
== -ENOSPC
&&
3178 ext4_should_retry_alloc(inode
->i_sb
, &retries
)) {
3182 mutex_unlock(&inode
->i_mutex
);
3183 return ret
> 0 ? ret2
: ret
;
3187 * Callback function called for each extent to gather FIEMAP information.
3189 static int ext4_ext_fiemap_cb(struct inode
*inode
, struct ext4_ext_path
*path
,
3190 struct ext4_ext_cache
*newex
, struct ext4_extent
*ex
,
3193 struct fiemap_extent_info
*fieinfo
= data
;
3194 unsigned char blksize_bits
= inode
->i_sb
->s_blocksize_bits
;
3201 logical
= (__u64
)newex
->ec_block
<< blksize_bits
;
3203 if (newex
->ec_type
== EXT4_EXT_CACHE_GAP
) {
3206 struct buffer_head
*bh
= NULL
;
3208 offset
= logical
>> PAGE_SHIFT
;
3209 page
= find_get_page(inode
->i_mapping
, offset
);
3210 if (!page
|| !page_has_buffers(page
))
3211 return EXT_CONTINUE
;
3213 bh
= page_buffers(page
);
3216 return EXT_CONTINUE
;
3218 if (buffer_delay(bh
)) {
3219 flags
|= FIEMAP_EXTENT_DELALLOC
;
3220 page_cache_release(page
);
3222 page_cache_release(page
);
3223 return EXT_CONTINUE
;
3227 physical
= (__u64
)newex
->ec_start
<< blksize_bits
;
3228 length
= (__u64
)newex
->ec_len
<< blksize_bits
;
3230 if (ex
&& ext4_ext_is_uninitialized(ex
))
3231 flags
|= FIEMAP_EXTENT_UNWRITTEN
;
3234 * If this extent reaches EXT_MAX_BLOCK, it must be last.
3236 * Or if ext4_ext_next_allocated_block is EXT_MAX_BLOCK,
3237 * this also indicates no more allocated blocks.
3239 * XXX this might miss a single-block extent at EXT_MAX_BLOCK
3241 if (ext4_ext_next_allocated_block(path
) == EXT_MAX_BLOCK
||
3242 newex
->ec_block
+ newex
->ec_len
- 1 == EXT_MAX_BLOCK
) {
3243 loff_t size
= i_size_read(inode
);
3244 loff_t bs
= EXT4_BLOCK_SIZE(inode
->i_sb
);
3246 flags
|= FIEMAP_EXTENT_LAST
;
3247 if ((flags
& FIEMAP_EXTENT_DELALLOC
) &&
3248 logical
+length
> size
)
3249 length
= (size
- logical
+ bs
- 1) & ~(bs
-1);
3252 error
= fiemap_fill_next_extent(fieinfo
, logical
, physical
,
3259 return EXT_CONTINUE
;
3262 /* fiemap flags we can handle specified here */
3263 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
3265 static int ext4_xattr_fiemap(struct inode
*inode
,
3266 struct fiemap_extent_info
*fieinfo
)
3270 __u32 flags
= FIEMAP_EXTENT_LAST
;
3271 int blockbits
= inode
->i_sb
->s_blocksize_bits
;
3275 if (EXT4_I(inode
)->i_state
& EXT4_STATE_XATTR
) {
3276 struct ext4_iloc iloc
;
3277 int offset
; /* offset of xattr in inode */
3279 error
= ext4_get_inode_loc(inode
, &iloc
);
3282 physical
= iloc
.bh
->b_blocknr
<< blockbits
;
3283 offset
= EXT4_GOOD_OLD_INODE_SIZE
+
3284 EXT4_I(inode
)->i_extra_isize
;
3286 length
= EXT4_SB(inode
->i_sb
)->s_inode_size
- offset
;
3287 flags
|= FIEMAP_EXTENT_DATA_INLINE
;
3288 } else { /* external block */
3289 physical
= EXT4_I(inode
)->i_file_acl
<< blockbits
;
3290 length
= inode
->i_sb
->s_blocksize
;
3294 error
= fiemap_fill_next_extent(fieinfo
, 0, physical
,
3296 return (error
< 0 ? error
: 0);
3299 int ext4_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
3300 __u64 start
, __u64 len
)
3302 ext4_lblk_t start_blk
;
3303 ext4_lblk_t len_blks
;
3306 /* fallback to generic here if not in extents fmt */
3307 if (!(EXT4_I(inode
)->i_flags
& EXT4_EXTENTS_FL
))
3308 return generic_block_fiemap(inode
, fieinfo
, start
, len
,
3311 if (fiemap_check_flags(fieinfo
, EXT4_FIEMAP_FLAGS
))
3314 if (fieinfo
->fi_flags
& FIEMAP_FLAG_XATTR
) {
3315 error
= ext4_xattr_fiemap(inode
, fieinfo
);
3317 start_blk
= start
>> inode
->i_sb
->s_blocksize_bits
;
3318 len_blks
= len
>> inode
->i_sb
->s_blocksize_bits
;
3321 * Walk the extent tree gathering extent information.
3322 * ext4_ext_fiemap_cb will push extents back to user.
3324 down_read(&EXT4_I(inode
)->i_data_sem
);
3325 error
= ext4_ext_walk_space(inode
, start_blk
, len_blks
,
3326 ext4_ext_fiemap_cb
, fieinfo
);
3327 up_read(&EXT4_I(inode
)->i_data_sem
);