2 * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
3 * Written by Alex Tomas <alex@clusterfs.com>
5 * Architecture independence:
6 * Copyright (c) 2005, Bull S.A.
7 * Written by Pierre Peiffer <pierre.peiffer@bull.net>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public Licens
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
24 * Extents support for EXT4
27 * - ext4*_error() should be used in some situations
28 * - analyze all BUG()/BUG_ON(), use -EIO where appropriate
29 * - smart tree reduction
33 #include <linux/time.h>
34 #include <linux/jbd2.h>
35 #include <linux/highuid.h>
36 #include <linux/pagemap.h>
37 #include <linux/quotaops.h>
38 #include <linux/string.h>
39 #include <linux/slab.h>
40 #include <asm/uaccess.h>
41 #include <linux/fiemap.h>
42 #include "ext4_jbd2.h"
43 #include "ext4_extents.h"
46 #include <trace/events/ext4.h>
49 * used by extent splitting.
51 #define EXT4_EXT_MAY_ZEROOUT 0x1 /* safe to zeroout if split fails \
53 #define EXT4_EXT_MARK_UNWRIT1 0x2 /* mark first half unwritten */
54 #define EXT4_EXT_MARK_UNWRIT2 0x4 /* mark second half unwritten */
56 #define EXT4_EXT_DATA_VALID1 0x8 /* first half contains valid data */
57 #define EXT4_EXT_DATA_VALID2 0x10 /* second half contains valid data */
59 static __le32
ext4_extent_block_csum(struct inode
*inode
,
60 struct ext4_extent_header
*eh
)
62 struct ext4_inode_info
*ei
= EXT4_I(inode
);
63 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
66 csum
= ext4_chksum(sbi
, ei
->i_csum_seed
, (__u8
*)eh
,
67 EXT4_EXTENT_TAIL_OFFSET(eh
));
68 return cpu_to_le32(csum
);
71 static int ext4_extent_block_csum_verify(struct inode
*inode
,
72 struct ext4_extent_header
*eh
)
74 struct ext4_extent_tail
*et
;
76 if (!ext4_has_metadata_csum(inode
->i_sb
))
79 et
= find_ext4_extent_tail(eh
);
80 if (et
->et_checksum
!= ext4_extent_block_csum(inode
, eh
))
85 static void ext4_extent_block_csum_set(struct inode
*inode
,
86 struct ext4_extent_header
*eh
)
88 struct ext4_extent_tail
*et
;
90 if (!ext4_has_metadata_csum(inode
->i_sb
))
93 et
= find_ext4_extent_tail(eh
);
94 et
->et_checksum
= ext4_extent_block_csum(inode
, eh
);
97 static int ext4_split_extent(handle_t
*handle
,
99 struct ext4_ext_path
**ppath
,
100 struct ext4_map_blocks
*map
,
104 static int ext4_split_extent_at(handle_t
*handle
,
106 struct ext4_ext_path
**ppath
,
111 static int ext4_find_delayed_extent(struct inode
*inode
,
112 struct extent_status
*newes
);
114 static int ext4_ext_truncate_extend_restart(handle_t
*handle
,
120 if (!ext4_handle_valid(handle
))
122 if (handle
->h_buffer_credits
> needed
)
124 err
= ext4_journal_extend(handle
, needed
);
127 err
= ext4_truncate_restart_trans(handle
, inode
, needed
);
139 static int ext4_ext_get_access(handle_t
*handle
, struct inode
*inode
,
140 struct ext4_ext_path
*path
)
143 /* path points to block */
144 BUFFER_TRACE(path
->p_bh
, "get_write_access");
145 return ext4_journal_get_write_access(handle
, path
->p_bh
);
147 /* path points to leaf/index in inode body */
148 /* we use in-core data, no need to protect them */
158 int __ext4_ext_dirty(const char *where
, unsigned int line
, handle_t
*handle
,
159 struct inode
*inode
, struct ext4_ext_path
*path
)
163 WARN_ON(!rwsem_is_locked(&EXT4_I(inode
)->i_data_sem
));
165 ext4_extent_block_csum_set(inode
, ext_block_hdr(path
->p_bh
));
166 /* path points to block */
167 err
= __ext4_handle_dirty_metadata(where
, line
, handle
,
170 /* path points to leaf/index in inode body */
171 err
= ext4_mark_inode_dirty(handle
, inode
);
176 static ext4_fsblk_t
ext4_ext_find_goal(struct inode
*inode
,
177 struct ext4_ext_path
*path
,
181 int depth
= path
->p_depth
;
182 struct ext4_extent
*ex
;
185 * Try to predict block placement assuming that we are
186 * filling in a file which will eventually be
187 * non-sparse --- i.e., in the case of libbfd writing
188 * an ELF object sections out-of-order but in a way
189 * the eventually results in a contiguous object or
190 * executable file, or some database extending a table
191 * space file. However, this is actually somewhat
192 * non-ideal if we are writing a sparse file such as
193 * qemu or KVM writing a raw image file that is going
194 * to stay fairly sparse, since it will end up
195 * fragmenting the file system's free space. Maybe we
196 * should have some hueristics or some way to allow
197 * userspace to pass a hint to file system,
198 * especially if the latter case turns out to be
201 ex
= path
[depth
].p_ext
;
203 ext4_fsblk_t ext_pblk
= ext4_ext_pblock(ex
);
204 ext4_lblk_t ext_block
= le32_to_cpu(ex
->ee_block
);
206 if (block
> ext_block
)
207 return ext_pblk
+ (block
- ext_block
);
209 return ext_pblk
- (ext_block
- block
);
212 /* it looks like index is empty;
213 * try to find starting block from index itself */
214 if (path
[depth
].p_bh
)
215 return path
[depth
].p_bh
->b_blocknr
;
218 /* OK. use inode's group */
219 return ext4_inode_to_goal_block(inode
);
223 * Allocation for a meta data block
226 ext4_ext_new_meta_block(handle_t
*handle
, struct inode
*inode
,
227 struct ext4_ext_path
*path
,
228 struct ext4_extent
*ex
, int *err
, unsigned int flags
)
230 ext4_fsblk_t goal
, newblock
;
232 goal
= ext4_ext_find_goal(inode
, path
, le32_to_cpu(ex
->ee_block
));
233 newblock
= ext4_new_meta_blocks(handle
, inode
, goal
, flags
,
238 static inline int ext4_ext_space_block(struct inode
*inode
, int check
)
242 size
= (inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
243 / sizeof(struct ext4_extent
);
244 #ifdef AGGRESSIVE_TEST
245 if (!check
&& size
> 6)
251 static inline int ext4_ext_space_block_idx(struct inode
*inode
, int check
)
255 size
= (inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
256 / sizeof(struct ext4_extent_idx
);
257 #ifdef AGGRESSIVE_TEST
258 if (!check
&& size
> 5)
264 static inline int ext4_ext_space_root(struct inode
*inode
, int check
)
268 size
= sizeof(EXT4_I(inode
)->i_data
);
269 size
-= sizeof(struct ext4_extent_header
);
270 size
/= sizeof(struct ext4_extent
);
271 #ifdef AGGRESSIVE_TEST
272 if (!check
&& size
> 3)
278 static inline int ext4_ext_space_root_idx(struct inode
*inode
, int check
)
282 size
= sizeof(EXT4_I(inode
)->i_data
);
283 size
-= sizeof(struct ext4_extent_header
);
284 size
/= sizeof(struct ext4_extent_idx
);
285 #ifdef AGGRESSIVE_TEST
286 if (!check
&& size
> 4)
293 ext4_force_split_extent_at(handle_t
*handle
, struct inode
*inode
,
294 struct ext4_ext_path
**ppath
, ext4_lblk_t lblk
,
297 struct ext4_ext_path
*path
= *ppath
;
298 int unwritten
= ext4_ext_is_unwritten(path
[path
->p_depth
].p_ext
);
300 return ext4_split_extent_at(handle
, inode
, ppath
, lblk
, unwritten
?
301 EXT4_EXT_MARK_UNWRIT1
|EXT4_EXT_MARK_UNWRIT2
: 0,
302 EXT4_EX_NOCACHE
| EXT4_GET_BLOCKS_PRE_IO
|
303 (nofail
? EXT4_GET_BLOCKS_METADATA_NOFAIL
:0));
307 * Calculate the number of metadata blocks needed
308 * to allocate @blocks
309 * Worse case is one block per extent
311 int ext4_ext_calc_metadata_amount(struct inode
*inode
, ext4_lblk_t lblock
)
313 struct ext4_inode_info
*ei
= EXT4_I(inode
);
316 idxs
= ((inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
317 / sizeof(struct ext4_extent_idx
));
320 * If the new delayed allocation block is contiguous with the
321 * previous da block, it can share index blocks with the
322 * previous block, so we only need to allocate a new index
323 * block every idxs leaf blocks. At ldxs**2 blocks, we need
324 * an additional index block, and at ldxs**3 blocks, yet
325 * another index blocks.
327 if (ei
->i_da_metadata_calc_len
&&
328 ei
->i_da_metadata_calc_last_lblock
+1 == lblock
) {
331 if ((ei
->i_da_metadata_calc_len
% idxs
) == 0)
333 if ((ei
->i_da_metadata_calc_len
% (idxs
*idxs
)) == 0)
335 if ((ei
->i_da_metadata_calc_len
% (idxs
*idxs
*idxs
)) == 0) {
337 ei
->i_da_metadata_calc_len
= 0;
339 ei
->i_da_metadata_calc_len
++;
340 ei
->i_da_metadata_calc_last_lblock
++;
345 * In the worst case we need a new set of index blocks at
346 * every level of the inode's extent tree.
348 ei
->i_da_metadata_calc_len
= 1;
349 ei
->i_da_metadata_calc_last_lblock
= lblock
;
350 return ext_depth(inode
) + 1;
354 ext4_ext_max_entries(struct inode
*inode
, int depth
)
358 if (depth
== ext_depth(inode
)) {
360 max
= ext4_ext_space_root(inode
, 1);
362 max
= ext4_ext_space_root_idx(inode
, 1);
365 max
= ext4_ext_space_block(inode
, 1);
367 max
= ext4_ext_space_block_idx(inode
, 1);
373 static int ext4_valid_extent(struct inode
*inode
, struct ext4_extent
*ext
)
375 ext4_fsblk_t block
= ext4_ext_pblock(ext
);
376 int len
= ext4_ext_get_actual_len(ext
);
377 ext4_lblk_t lblock
= le32_to_cpu(ext
->ee_block
);
378 ext4_lblk_t last
= lblock
+ len
- 1;
382 return ext4_data_block_valid(EXT4_SB(inode
->i_sb
), block
, len
);
385 static int ext4_valid_extent_idx(struct inode
*inode
,
386 struct ext4_extent_idx
*ext_idx
)
388 ext4_fsblk_t block
= ext4_idx_pblock(ext_idx
);
390 return ext4_data_block_valid(EXT4_SB(inode
->i_sb
), block
, 1);
393 static int ext4_valid_extent_entries(struct inode
*inode
,
394 struct ext4_extent_header
*eh
,
397 unsigned short entries
;
398 if (eh
->eh_entries
== 0)
401 entries
= le16_to_cpu(eh
->eh_entries
);
405 struct ext4_extent
*ext
= EXT_FIRST_EXTENT(eh
);
406 struct ext4_super_block
*es
= EXT4_SB(inode
->i_sb
)->s_es
;
407 ext4_fsblk_t pblock
= 0;
408 ext4_lblk_t lblock
= 0;
409 ext4_lblk_t prev
= 0;
412 if (!ext4_valid_extent(inode
, ext
))
415 /* Check for overlapping extents */
416 lblock
= le32_to_cpu(ext
->ee_block
);
417 len
= ext4_ext_get_actual_len(ext
);
418 if ((lblock
<= prev
) && prev
) {
419 pblock
= ext4_ext_pblock(ext
);
420 es
->s_last_error_block
= cpu_to_le64(pblock
);
425 prev
= lblock
+ len
- 1;
428 struct ext4_extent_idx
*ext_idx
= EXT_FIRST_INDEX(eh
);
430 if (!ext4_valid_extent_idx(inode
, ext_idx
))
439 static int __ext4_ext_check(const char *function
, unsigned int line
,
440 struct inode
*inode
, struct ext4_extent_header
*eh
,
441 int depth
, ext4_fsblk_t pblk
)
443 const char *error_msg
;
446 if (unlikely(eh
->eh_magic
!= EXT4_EXT_MAGIC
)) {
447 error_msg
= "invalid magic";
450 if (unlikely(le16_to_cpu(eh
->eh_depth
) != depth
)) {
451 error_msg
= "unexpected eh_depth";
454 if (unlikely(eh
->eh_max
== 0)) {
455 error_msg
= "invalid eh_max";
458 max
= ext4_ext_max_entries(inode
, depth
);
459 if (unlikely(le16_to_cpu(eh
->eh_max
) > max
)) {
460 error_msg
= "too large eh_max";
463 if (unlikely(le16_to_cpu(eh
->eh_entries
) > le16_to_cpu(eh
->eh_max
))) {
464 error_msg
= "invalid eh_entries";
467 if (!ext4_valid_extent_entries(inode
, eh
, depth
)) {
468 error_msg
= "invalid extent entries";
471 /* Verify checksum on non-root extent tree nodes */
472 if (ext_depth(inode
) != depth
&&
473 !ext4_extent_block_csum_verify(inode
, eh
)) {
474 error_msg
= "extent tree corrupted";
480 ext4_error_inode(inode
, function
, line
, 0,
481 "pblk %llu bad header/extent: %s - magic %x, "
482 "entries %u, max %u(%u), depth %u(%u)",
483 (unsigned long long) pblk
, error_msg
,
484 le16_to_cpu(eh
->eh_magic
),
485 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
),
486 max
, le16_to_cpu(eh
->eh_depth
), depth
);
490 #define ext4_ext_check(inode, eh, depth, pblk) \
491 __ext4_ext_check(__func__, __LINE__, (inode), (eh), (depth), (pblk))
493 int ext4_ext_check_inode(struct inode
*inode
)
495 return ext4_ext_check(inode
, ext_inode_hdr(inode
), ext_depth(inode
), 0);
498 static struct buffer_head
*
499 __read_extent_tree_block(const char *function
, unsigned int line
,
500 struct inode
*inode
, ext4_fsblk_t pblk
, int depth
,
503 struct buffer_head
*bh
;
506 bh
= sb_getblk(inode
->i_sb
, pblk
);
508 return ERR_PTR(-ENOMEM
);
510 if (!bh_uptodate_or_lock(bh
)) {
511 trace_ext4_ext_load_extent(inode
, pblk
, _RET_IP_
);
512 err
= bh_submit_read(bh
);
516 if (buffer_verified(bh
) && !(flags
& EXT4_EX_FORCE_CACHE
))
518 err
= __ext4_ext_check(function
, line
, inode
,
519 ext_block_hdr(bh
), depth
, pblk
);
522 set_buffer_verified(bh
);
524 * If this is a leaf block, cache all of its entries
526 if (!(flags
& EXT4_EX_NOCACHE
) && depth
== 0) {
527 struct ext4_extent_header
*eh
= ext_block_hdr(bh
);
528 struct ext4_extent
*ex
= EXT_FIRST_EXTENT(eh
);
529 ext4_lblk_t prev
= 0;
532 for (i
= le16_to_cpu(eh
->eh_entries
); i
> 0; i
--, ex
++) {
533 unsigned int status
= EXTENT_STATUS_WRITTEN
;
534 ext4_lblk_t lblk
= le32_to_cpu(ex
->ee_block
);
535 int len
= ext4_ext_get_actual_len(ex
);
537 if (prev
&& (prev
!= lblk
))
538 ext4_es_cache_extent(inode
, prev
,
542 if (ext4_ext_is_unwritten(ex
))
543 status
= EXTENT_STATUS_UNWRITTEN
;
544 ext4_es_cache_extent(inode
, lblk
, len
,
545 ext4_ext_pblock(ex
), status
);
556 #define read_extent_tree_block(inode, pblk, depth, flags) \
557 __read_extent_tree_block(__func__, __LINE__, (inode), (pblk), \
561 * This function is called to cache a file's extent information in the
564 int ext4_ext_precache(struct inode
*inode
)
566 struct ext4_inode_info
*ei
= EXT4_I(inode
);
567 struct ext4_ext_path
*path
= NULL
;
568 struct buffer_head
*bh
;
569 int i
= 0, depth
, ret
= 0;
571 if (!ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
572 return 0; /* not an extent-mapped inode */
574 down_read(&ei
->i_data_sem
);
575 depth
= ext_depth(inode
);
577 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 1),
580 up_read(&ei
->i_data_sem
);
584 /* Don't cache anything if there are no external extent blocks */
587 path
[0].p_hdr
= ext_inode_hdr(inode
);
588 ret
= ext4_ext_check(inode
, path
[0].p_hdr
, depth
, 0);
591 path
[0].p_idx
= EXT_FIRST_INDEX(path
[0].p_hdr
);
594 * If this is a leaf block or we've reached the end of
595 * the index block, go up
598 path
[i
].p_idx
> EXT_LAST_INDEX(path
[i
].p_hdr
)) {
599 brelse(path
[i
].p_bh
);
604 bh
= read_extent_tree_block(inode
,
605 ext4_idx_pblock(path
[i
].p_idx
++),
607 EXT4_EX_FORCE_CACHE
);
614 path
[i
].p_hdr
= ext_block_hdr(bh
);
615 path
[i
].p_idx
= EXT_FIRST_INDEX(path
[i
].p_hdr
);
617 ext4_set_inode_state(inode
, EXT4_STATE_EXT_PRECACHED
);
619 up_read(&ei
->i_data_sem
);
620 ext4_ext_drop_refs(path
);
626 static void ext4_ext_show_path(struct inode
*inode
, struct ext4_ext_path
*path
)
628 int k
, l
= path
->p_depth
;
631 for (k
= 0; k
<= l
; k
++, path
++) {
633 ext_debug(" %d->%llu", le32_to_cpu(path
->p_idx
->ei_block
),
634 ext4_idx_pblock(path
->p_idx
));
635 } else if (path
->p_ext
) {
636 ext_debug(" %d:[%d]%d:%llu ",
637 le32_to_cpu(path
->p_ext
->ee_block
),
638 ext4_ext_is_unwritten(path
->p_ext
),
639 ext4_ext_get_actual_len(path
->p_ext
),
640 ext4_ext_pblock(path
->p_ext
));
647 static void ext4_ext_show_leaf(struct inode
*inode
, struct ext4_ext_path
*path
)
649 int depth
= ext_depth(inode
);
650 struct ext4_extent_header
*eh
;
651 struct ext4_extent
*ex
;
657 eh
= path
[depth
].p_hdr
;
658 ex
= EXT_FIRST_EXTENT(eh
);
660 ext_debug("Displaying leaf extents for inode %lu\n", inode
->i_ino
);
662 for (i
= 0; i
< le16_to_cpu(eh
->eh_entries
); i
++, ex
++) {
663 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex
->ee_block
),
664 ext4_ext_is_unwritten(ex
),
665 ext4_ext_get_actual_len(ex
), ext4_ext_pblock(ex
));
670 static void ext4_ext_show_move(struct inode
*inode
, struct ext4_ext_path
*path
,
671 ext4_fsblk_t newblock
, int level
)
673 int depth
= ext_depth(inode
);
674 struct ext4_extent
*ex
;
676 if (depth
!= level
) {
677 struct ext4_extent_idx
*idx
;
678 idx
= path
[level
].p_idx
;
679 while (idx
<= EXT_MAX_INDEX(path
[level
].p_hdr
)) {
680 ext_debug("%d: move %d:%llu in new index %llu\n", level
,
681 le32_to_cpu(idx
->ei_block
),
682 ext4_idx_pblock(idx
),
690 ex
= path
[depth
].p_ext
;
691 while (ex
<= EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
692 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
693 le32_to_cpu(ex
->ee_block
),
695 ext4_ext_is_unwritten(ex
),
696 ext4_ext_get_actual_len(ex
),
703 #define ext4_ext_show_path(inode, path)
704 #define ext4_ext_show_leaf(inode, path)
705 #define ext4_ext_show_move(inode, path, newblock, level)
708 void ext4_ext_drop_refs(struct ext4_ext_path
*path
)
714 depth
= path
->p_depth
;
715 for (i
= 0; i
<= depth
; i
++, path
++)
723 * ext4_ext_binsearch_idx:
724 * binary search for the closest index of the given block
725 * the header must be checked before calling this
728 ext4_ext_binsearch_idx(struct inode
*inode
,
729 struct ext4_ext_path
*path
, ext4_lblk_t block
)
731 struct ext4_extent_header
*eh
= path
->p_hdr
;
732 struct ext4_extent_idx
*r
, *l
, *m
;
735 ext_debug("binsearch for %u(idx): ", block
);
737 l
= EXT_FIRST_INDEX(eh
) + 1;
738 r
= EXT_LAST_INDEX(eh
);
741 if (block
< le32_to_cpu(m
->ei_block
))
745 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ei_block
),
746 m
, le32_to_cpu(m
->ei_block
),
747 r
, le32_to_cpu(r
->ei_block
));
751 ext_debug(" -> %u->%lld ", le32_to_cpu(path
->p_idx
->ei_block
),
752 ext4_idx_pblock(path
->p_idx
));
754 #ifdef CHECK_BINSEARCH
756 struct ext4_extent_idx
*chix
, *ix
;
759 chix
= ix
= EXT_FIRST_INDEX(eh
);
760 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ix
++) {
762 le32_to_cpu(ix
->ei_block
) <= le32_to_cpu(ix
[-1].ei_block
)) {
763 printk(KERN_DEBUG
"k=%d, ix=0x%p, "
765 ix
, EXT_FIRST_INDEX(eh
));
766 printk(KERN_DEBUG
"%u <= %u\n",
767 le32_to_cpu(ix
->ei_block
),
768 le32_to_cpu(ix
[-1].ei_block
));
770 BUG_ON(k
&& le32_to_cpu(ix
->ei_block
)
771 <= le32_to_cpu(ix
[-1].ei_block
));
772 if (block
< le32_to_cpu(ix
->ei_block
))
776 BUG_ON(chix
!= path
->p_idx
);
783 * ext4_ext_binsearch:
784 * binary search for closest extent of the given block
785 * the header must be checked before calling this
788 ext4_ext_binsearch(struct inode
*inode
,
789 struct ext4_ext_path
*path
, ext4_lblk_t block
)
791 struct ext4_extent_header
*eh
= path
->p_hdr
;
792 struct ext4_extent
*r
, *l
, *m
;
794 if (eh
->eh_entries
== 0) {
796 * this leaf is empty:
797 * we get such a leaf in split/add case
802 ext_debug("binsearch for %u: ", block
);
804 l
= EXT_FIRST_EXTENT(eh
) + 1;
805 r
= EXT_LAST_EXTENT(eh
);
809 if (block
< le32_to_cpu(m
->ee_block
))
813 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ee_block
),
814 m
, le32_to_cpu(m
->ee_block
),
815 r
, le32_to_cpu(r
->ee_block
));
819 ext_debug(" -> %d:%llu:[%d]%d ",
820 le32_to_cpu(path
->p_ext
->ee_block
),
821 ext4_ext_pblock(path
->p_ext
),
822 ext4_ext_is_unwritten(path
->p_ext
),
823 ext4_ext_get_actual_len(path
->p_ext
));
825 #ifdef CHECK_BINSEARCH
827 struct ext4_extent
*chex
, *ex
;
830 chex
= ex
= EXT_FIRST_EXTENT(eh
);
831 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ex
++) {
832 BUG_ON(k
&& le32_to_cpu(ex
->ee_block
)
833 <= le32_to_cpu(ex
[-1].ee_block
));
834 if (block
< le32_to_cpu(ex
->ee_block
))
838 BUG_ON(chex
!= path
->p_ext
);
844 int ext4_ext_tree_init(handle_t
*handle
, struct inode
*inode
)
846 struct ext4_extent_header
*eh
;
848 eh
= ext_inode_hdr(inode
);
851 eh
->eh_magic
= EXT4_EXT_MAGIC
;
852 eh
->eh_max
= cpu_to_le16(ext4_ext_space_root(inode
, 0));
853 ext4_mark_inode_dirty(handle
, inode
);
857 struct ext4_ext_path
*
858 ext4_find_extent(struct inode
*inode
, ext4_lblk_t block
,
859 struct ext4_ext_path
**orig_path
, int flags
)
861 struct ext4_extent_header
*eh
;
862 struct buffer_head
*bh
;
863 struct ext4_ext_path
*path
= orig_path
? *orig_path
: NULL
;
864 short int depth
, i
, ppos
= 0;
867 eh
= ext_inode_hdr(inode
);
868 depth
= ext_depth(inode
);
871 ext4_ext_drop_refs(path
);
872 if (depth
> path
[0].p_maxdepth
) {
874 *orig_path
= path
= NULL
;
878 /* account possible depth increase */
879 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 2),
882 return ERR_PTR(-ENOMEM
);
883 path
[0].p_maxdepth
= depth
+ 1;
889 /* walk through the tree */
891 ext_debug("depth %d: num %d, max %d\n",
892 ppos
, le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
894 ext4_ext_binsearch_idx(inode
, path
+ ppos
, block
);
895 path
[ppos
].p_block
= ext4_idx_pblock(path
[ppos
].p_idx
);
896 path
[ppos
].p_depth
= i
;
897 path
[ppos
].p_ext
= NULL
;
899 bh
= read_extent_tree_block(inode
, path
[ppos
].p_block
, --i
,
901 if (unlikely(IS_ERR(bh
))) {
906 eh
= ext_block_hdr(bh
);
908 if (unlikely(ppos
> depth
)) {
910 EXT4_ERROR_INODE(inode
,
911 "ppos %d > depth %d", ppos
, depth
);
915 path
[ppos
].p_bh
= bh
;
916 path
[ppos
].p_hdr
= eh
;
919 path
[ppos
].p_depth
= i
;
920 path
[ppos
].p_ext
= NULL
;
921 path
[ppos
].p_idx
= NULL
;
924 ext4_ext_binsearch(inode
, path
+ ppos
, block
);
925 /* if not an empty leaf */
926 if (path
[ppos
].p_ext
)
927 path
[ppos
].p_block
= ext4_ext_pblock(path
[ppos
].p_ext
);
929 ext4_ext_show_path(inode
, path
);
934 ext4_ext_drop_refs(path
);
942 * ext4_ext_insert_index:
943 * insert new index [@logical;@ptr] into the block at @curp;
944 * check where to insert: before @curp or after @curp
946 static int ext4_ext_insert_index(handle_t
*handle
, struct inode
*inode
,
947 struct ext4_ext_path
*curp
,
948 int logical
, ext4_fsblk_t ptr
)
950 struct ext4_extent_idx
*ix
;
953 err
= ext4_ext_get_access(handle
, inode
, curp
);
957 if (unlikely(logical
== le32_to_cpu(curp
->p_idx
->ei_block
))) {
958 EXT4_ERROR_INODE(inode
,
959 "logical %d == ei_block %d!",
960 logical
, le32_to_cpu(curp
->p_idx
->ei_block
));
964 if (unlikely(le16_to_cpu(curp
->p_hdr
->eh_entries
)
965 >= le16_to_cpu(curp
->p_hdr
->eh_max
))) {
966 EXT4_ERROR_INODE(inode
,
967 "eh_entries %d >= eh_max %d!",
968 le16_to_cpu(curp
->p_hdr
->eh_entries
),
969 le16_to_cpu(curp
->p_hdr
->eh_max
));
973 if (logical
> le32_to_cpu(curp
->p_idx
->ei_block
)) {
975 ext_debug("insert new index %d after: %llu\n", logical
, ptr
);
976 ix
= curp
->p_idx
+ 1;
979 ext_debug("insert new index %d before: %llu\n", logical
, ptr
);
983 len
= EXT_LAST_INDEX(curp
->p_hdr
) - ix
+ 1;
986 ext_debug("insert new index %d: "
987 "move %d indices from 0x%p to 0x%p\n",
988 logical
, len
, ix
, ix
+ 1);
989 memmove(ix
+ 1, ix
, len
* sizeof(struct ext4_extent_idx
));
992 if (unlikely(ix
> EXT_MAX_INDEX(curp
->p_hdr
))) {
993 EXT4_ERROR_INODE(inode
, "ix > EXT_MAX_INDEX!");
997 ix
->ei_block
= cpu_to_le32(logical
);
998 ext4_idx_store_pblock(ix
, ptr
);
999 le16_add_cpu(&curp
->p_hdr
->eh_entries
, 1);
1001 if (unlikely(ix
> EXT_LAST_INDEX(curp
->p_hdr
))) {
1002 EXT4_ERROR_INODE(inode
, "ix > EXT_LAST_INDEX!");
1006 err
= ext4_ext_dirty(handle
, inode
, curp
);
1007 ext4_std_error(inode
->i_sb
, err
);
1014 * inserts new subtree into the path, using free index entry
1016 * - allocates all needed blocks (new leaf and all intermediate index blocks)
1017 * - makes decision where to split
1018 * - moves remaining extents and index entries (right to the split point)
1019 * into the newly allocated blocks
1020 * - initializes subtree
1022 static int ext4_ext_split(handle_t
*handle
, struct inode
*inode
,
1024 struct ext4_ext_path
*path
,
1025 struct ext4_extent
*newext
, int at
)
1027 struct buffer_head
*bh
= NULL
;
1028 int depth
= ext_depth(inode
);
1029 struct ext4_extent_header
*neh
;
1030 struct ext4_extent_idx
*fidx
;
1031 int i
= at
, k
, m
, a
;
1032 ext4_fsblk_t newblock
, oldblock
;
1034 ext4_fsblk_t
*ablocks
= NULL
; /* array of allocated blocks */
1037 /* make decision: where to split? */
1038 /* FIXME: now decision is simplest: at current extent */
1040 /* if current leaf will be split, then we should use
1041 * border from split point */
1042 if (unlikely(path
[depth
].p_ext
> EXT_MAX_EXTENT(path
[depth
].p_hdr
))) {
1043 EXT4_ERROR_INODE(inode
, "p_ext > EXT_MAX_EXTENT!");
1046 if (path
[depth
].p_ext
!= EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
1047 border
= path
[depth
].p_ext
[1].ee_block
;
1048 ext_debug("leaf will be split."
1049 " next leaf starts at %d\n",
1050 le32_to_cpu(border
));
1052 border
= newext
->ee_block
;
1053 ext_debug("leaf will be added."
1054 " next leaf starts at %d\n",
1055 le32_to_cpu(border
));
1059 * If error occurs, then we break processing
1060 * and mark filesystem read-only. index won't
1061 * be inserted and tree will be in consistent
1062 * state. Next mount will repair buffers too.
1066 * Get array to track all allocated blocks.
1067 * We need this to handle errors and free blocks
1070 ablocks
= kzalloc(sizeof(ext4_fsblk_t
) * depth
, GFP_NOFS
);
1074 /* allocate all needed blocks */
1075 ext_debug("allocate %d blocks for indexes/leaf\n", depth
- at
);
1076 for (a
= 0; a
< depth
- at
; a
++) {
1077 newblock
= ext4_ext_new_meta_block(handle
, inode
, path
,
1078 newext
, &err
, flags
);
1081 ablocks
[a
] = newblock
;
1084 /* initialize new leaf */
1085 newblock
= ablocks
[--a
];
1086 if (unlikely(newblock
== 0)) {
1087 EXT4_ERROR_INODE(inode
, "newblock == 0!");
1091 bh
= sb_getblk(inode
->i_sb
, newblock
);
1092 if (unlikely(!bh
)) {
1098 err
= ext4_journal_get_create_access(handle
, bh
);
1102 neh
= ext_block_hdr(bh
);
1103 neh
->eh_entries
= 0;
1104 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
, 0));
1105 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1108 /* move remainder of path[depth] to the new leaf */
1109 if (unlikely(path
[depth
].p_hdr
->eh_entries
!=
1110 path
[depth
].p_hdr
->eh_max
)) {
1111 EXT4_ERROR_INODE(inode
, "eh_entries %d != eh_max %d!",
1112 path
[depth
].p_hdr
->eh_entries
,
1113 path
[depth
].p_hdr
->eh_max
);
1117 /* start copy from next extent */
1118 m
= EXT_MAX_EXTENT(path
[depth
].p_hdr
) - path
[depth
].p_ext
++;
1119 ext4_ext_show_move(inode
, path
, newblock
, depth
);
1121 struct ext4_extent
*ex
;
1122 ex
= EXT_FIRST_EXTENT(neh
);
1123 memmove(ex
, path
[depth
].p_ext
, sizeof(struct ext4_extent
) * m
);
1124 le16_add_cpu(&neh
->eh_entries
, m
);
1127 ext4_extent_block_csum_set(inode
, neh
);
1128 set_buffer_uptodate(bh
);
1131 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1137 /* correct old leaf */
1139 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
1142 le16_add_cpu(&path
[depth
].p_hdr
->eh_entries
, -m
);
1143 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
1149 /* create intermediate indexes */
1151 if (unlikely(k
< 0)) {
1152 EXT4_ERROR_INODE(inode
, "k %d < 0!", k
);
1157 ext_debug("create %d intermediate indices\n", k
);
1158 /* insert new index into current index block */
1159 /* current depth stored in i var */
1162 oldblock
= newblock
;
1163 newblock
= ablocks
[--a
];
1164 bh
= sb_getblk(inode
->i_sb
, newblock
);
1165 if (unlikely(!bh
)) {
1171 err
= ext4_journal_get_create_access(handle
, bh
);
1175 neh
= ext_block_hdr(bh
);
1176 neh
->eh_entries
= cpu_to_le16(1);
1177 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1178 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
, 0));
1179 neh
->eh_depth
= cpu_to_le16(depth
- i
);
1180 fidx
= EXT_FIRST_INDEX(neh
);
1181 fidx
->ei_block
= border
;
1182 ext4_idx_store_pblock(fidx
, oldblock
);
1184 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
1185 i
, newblock
, le32_to_cpu(border
), oldblock
);
1187 /* move remainder of path[i] to the new index block */
1188 if (unlikely(EXT_MAX_INDEX(path
[i
].p_hdr
) !=
1189 EXT_LAST_INDEX(path
[i
].p_hdr
))) {
1190 EXT4_ERROR_INODE(inode
,
1191 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
1192 le32_to_cpu(path
[i
].p_ext
->ee_block
));
1196 /* start copy indexes */
1197 m
= EXT_MAX_INDEX(path
[i
].p_hdr
) - path
[i
].p_idx
++;
1198 ext_debug("cur 0x%p, last 0x%p\n", path
[i
].p_idx
,
1199 EXT_MAX_INDEX(path
[i
].p_hdr
));
1200 ext4_ext_show_move(inode
, path
, newblock
, i
);
1202 memmove(++fidx
, path
[i
].p_idx
,
1203 sizeof(struct ext4_extent_idx
) * m
);
1204 le16_add_cpu(&neh
->eh_entries
, m
);
1206 ext4_extent_block_csum_set(inode
, neh
);
1207 set_buffer_uptodate(bh
);
1210 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1216 /* correct old index */
1218 err
= ext4_ext_get_access(handle
, inode
, path
+ i
);
1221 le16_add_cpu(&path
[i
].p_hdr
->eh_entries
, -m
);
1222 err
= ext4_ext_dirty(handle
, inode
, path
+ i
);
1230 /* insert new index */
1231 err
= ext4_ext_insert_index(handle
, inode
, path
+ at
,
1232 le32_to_cpu(border
), newblock
);
1236 if (buffer_locked(bh
))
1242 /* free all allocated blocks in error case */
1243 for (i
= 0; i
< depth
; i
++) {
1246 ext4_free_blocks(handle
, inode
, NULL
, ablocks
[i
], 1,
1247 EXT4_FREE_BLOCKS_METADATA
);
1256 * ext4_ext_grow_indepth:
1257 * implements tree growing procedure:
1258 * - allocates new block
1259 * - moves top-level data (index block or leaf) into the new block
1260 * - initializes new top-level, creating index that points to the
1261 * just created block
1263 static int ext4_ext_grow_indepth(handle_t
*handle
, struct inode
*inode
,
1266 struct ext4_extent_header
*neh
;
1267 struct buffer_head
*bh
;
1268 ext4_fsblk_t newblock
, goal
= 0;
1269 struct ext4_super_block
*es
= EXT4_SB(inode
->i_sb
)->s_es
;
1272 /* Try to prepend new index to old one */
1273 if (ext_depth(inode
))
1274 goal
= ext4_idx_pblock(EXT_FIRST_INDEX(ext_inode_hdr(inode
)));
1275 if (goal
> le32_to_cpu(es
->s_first_data_block
)) {
1276 flags
|= EXT4_MB_HINT_TRY_GOAL
;
1279 goal
= ext4_inode_to_goal_block(inode
);
1280 newblock
= ext4_new_meta_blocks(handle
, inode
, goal
, flags
,
1285 bh
= sb_getblk(inode
->i_sb
, newblock
);
1290 err
= ext4_journal_get_create_access(handle
, bh
);
1296 /* move top-level index/leaf into new block */
1297 memmove(bh
->b_data
, EXT4_I(inode
)->i_data
,
1298 sizeof(EXT4_I(inode
)->i_data
));
1300 /* set size of new block */
1301 neh
= ext_block_hdr(bh
);
1302 /* old root could have indexes or leaves
1303 * so calculate e_max right way */
1304 if (ext_depth(inode
))
1305 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
, 0));
1307 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
, 0));
1308 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1309 ext4_extent_block_csum_set(inode
, neh
);
1310 set_buffer_uptodate(bh
);
1313 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1317 /* Update top-level index: num,max,pointer */
1318 neh
= ext_inode_hdr(inode
);
1319 neh
->eh_entries
= cpu_to_le16(1);
1320 ext4_idx_store_pblock(EXT_FIRST_INDEX(neh
), newblock
);
1321 if (neh
->eh_depth
== 0) {
1322 /* Root extent block becomes index block */
1323 neh
->eh_max
= cpu_to_le16(ext4_ext_space_root_idx(inode
, 0));
1324 EXT_FIRST_INDEX(neh
)->ei_block
=
1325 EXT_FIRST_EXTENT(neh
)->ee_block
;
1327 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1328 le16_to_cpu(neh
->eh_entries
), le16_to_cpu(neh
->eh_max
),
1329 le32_to_cpu(EXT_FIRST_INDEX(neh
)->ei_block
),
1330 ext4_idx_pblock(EXT_FIRST_INDEX(neh
)));
1332 le16_add_cpu(&neh
->eh_depth
, 1);
1333 ext4_mark_inode_dirty(handle
, inode
);
1341 * ext4_ext_create_new_leaf:
1342 * finds empty index and adds new leaf.
1343 * if no free index is found, then it requests in-depth growing.
1345 static int ext4_ext_create_new_leaf(handle_t
*handle
, struct inode
*inode
,
1346 unsigned int mb_flags
,
1347 unsigned int gb_flags
,
1348 struct ext4_ext_path
**ppath
,
1349 struct ext4_extent
*newext
)
1351 struct ext4_ext_path
*path
= *ppath
;
1352 struct ext4_ext_path
*curp
;
1353 int depth
, i
, err
= 0;
1356 i
= depth
= ext_depth(inode
);
1358 /* walk up to the tree and look for free index entry */
1359 curp
= path
+ depth
;
1360 while (i
> 0 && !EXT_HAS_FREE_INDEX(curp
)) {
1365 /* we use already allocated block for index block,
1366 * so subsequent data blocks should be contiguous */
1367 if (EXT_HAS_FREE_INDEX(curp
)) {
1368 /* if we found index with free entry, then use that
1369 * entry: create all needed subtree and add new leaf */
1370 err
= ext4_ext_split(handle
, inode
, mb_flags
, path
, newext
, i
);
1375 path
= ext4_find_extent(inode
,
1376 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1379 err
= PTR_ERR(path
);
1381 /* tree is full, time to grow in depth */
1382 err
= ext4_ext_grow_indepth(handle
, inode
, mb_flags
);
1387 path
= ext4_find_extent(inode
,
1388 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1391 err
= PTR_ERR(path
);
1396 * only first (depth 0 -> 1) produces free space;
1397 * in all other cases we have to split the grown tree
1399 depth
= ext_depth(inode
);
1400 if (path
[depth
].p_hdr
->eh_entries
== path
[depth
].p_hdr
->eh_max
) {
1401 /* now we need to split */
1411 * search the closest allocated block to the left for *logical
1412 * and returns it at @logical + it's physical address at @phys
1413 * if *logical is the smallest allocated block, the function
1414 * returns 0 at @phys
1415 * return value contains 0 (success) or error code
1417 static int ext4_ext_search_left(struct inode
*inode
,
1418 struct ext4_ext_path
*path
,
1419 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
)
1421 struct ext4_extent_idx
*ix
;
1422 struct ext4_extent
*ex
;
1425 if (unlikely(path
== NULL
)) {
1426 EXT4_ERROR_INODE(inode
, "path == NULL *logical %d!", *logical
);
1429 depth
= path
->p_depth
;
1432 if (depth
== 0 && path
->p_ext
== NULL
)
1435 /* usually extent in the path covers blocks smaller
1436 * then *logical, but it can be that extent is the
1437 * first one in the file */
1439 ex
= path
[depth
].p_ext
;
1440 ee_len
= ext4_ext_get_actual_len(ex
);
1441 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1442 if (unlikely(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
)) {
1443 EXT4_ERROR_INODE(inode
,
1444 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
1445 *logical
, le32_to_cpu(ex
->ee_block
));
1448 while (--depth
>= 0) {
1449 ix
= path
[depth
].p_idx
;
1450 if (unlikely(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
))) {
1451 EXT4_ERROR_INODE(inode
,
1452 "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
1453 ix
!= NULL
? le32_to_cpu(ix
->ei_block
) : 0,
1454 EXT_FIRST_INDEX(path
[depth
].p_hdr
) != NULL
?
1455 le32_to_cpu(EXT_FIRST_INDEX(path
[depth
].p_hdr
)->ei_block
) : 0,
1463 if (unlikely(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
))) {
1464 EXT4_ERROR_INODE(inode
,
1465 "logical %d < ee_block %d + ee_len %d!",
1466 *logical
, le32_to_cpu(ex
->ee_block
), ee_len
);
1470 *logical
= le32_to_cpu(ex
->ee_block
) + ee_len
- 1;
1471 *phys
= ext4_ext_pblock(ex
) + ee_len
- 1;
1476 * search the closest allocated block to the right for *logical
1477 * and returns it at @logical + it's physical address at @phys
1478 * if *logical is the largest allocated block, the function
1479 * returns 0 at @phys
1480 * return value contains 0 (success) or error code
1482 static int ext4_ext_search_right(struct inode
*inode
,
1483 struct ext4_ext_path
*path
,
1484 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
,
1485 struct ext4_extent
**ret_ex
)
1487 struct buffer_head
*bh
= NULL
;
1488 struct ext4_extent_header
*eh
;
1489 struct ext4_extent_idx
*ix
;
1490 struct ext4_extent
*ex
;
1492 int depth
; /* Note, NOT eh_depth; depth from top of tree */
1495 if (unlikely(path
== NULL
)) {
1496 EXT4_ERROR_INODE(inode
, "path == NULL *logical %d!", *logical
);
1499 depth
= path
->p_depth
;
1502 if (depth
== 0 && path
->p_ext
== NULL
)
1505 /* usually extent in the path covers blocks smaller
1506 * then *logical, but it can be that extent is the
1507 * first one in the file */
1509 ex
= path
[depth
].p_ext
;
1510 ee_len
= ext4_ext_get_actual_len(ex
);
1511 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1512 if (unlikely(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
)) {
1513 EXT4_ERROR_INODE(inode
,
1514 "first_extent(path[%d].p_hdr) != ex",
1518 while (--depth
>= 0) {
1519 ix
= path
[depth
].p_idx
;
1520 if (unlikely(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
))) {
1521 EXT4_ERROR_INODE(inode
,
1522 "ix != EXT_FIRST_INDEX *logical %d!",
1530 if (unlikely(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
))) {
1531 EXT4_ERROR_INODE(inode
,
1532 "logical %d < ee_block %d + ee_len %d!",
1533 *logical
, le32_to_cpu(ex
->ee_block
), ee_len
);
1537 if (ex
!= EXT_LAST_EXTENT(path
[depth
].p_hdr
)) {
1538 /* next allocated block in this leaf */
1543 /* go up and search for index to the right */
1544 while (--depth
>= 0) {
1545 ix
= path
[depth
].p_idx
;
1546 if (ix
!= EXT_LAST_INDEX(path
[depth
].p_hdr
))
1550 /* we've gone up to the root and found no index to the right */
1554 /* we've found index to the right, let's
1555 * follow it and find the closest allocated
1556 * block to the right */
1558 block
= ext4_idx_pblock(ix
);
1559 while (++depth
< path
->p_depth
) {
1560 /* subtract from p_depth to get proper eh_depth */
1561 bh
= read_extent_tree_block(inode
, block
,
1562 path
->p_depth
- depth
, 0);
1565 eh
= ext_block_hdr(bh
);
1566 ix
= EXT_FIRST_INDEX(eh
);
1567 block
= ext4_idx_pblock(ix
);
1571 bh
= read_extent_tree_block(inode
, block
, path
->p_depth
- depth
, 0);
1574 eh
= ext_block_hdr(bh
);
1575 ex
= EXT_FIRST_EXTENT(eh
);
1577 *logical
= le32_to_cpu(ex
->ee_block
);
1578 *phys
= ext4_ext_pblock(ex
);
1586 * ext4_ext_next_allocated_block:
1587 * returns allocated block in subsequent extent or EXT_MAX_BLOCKS.
1588 * NOTE: it considers block number from index entry as
1589 * allocated block. Thus, index entries have to be consistent
1593 ext4_ext_next_allocated_block(struct ext4_ext_path
*path
)
1597 BUG_ON(path
== NULL
);
1598 depth
= path
->p_depth
;
1600 if (depth
== 0 && path
->p_ext
== NULL
)
1601 return EXT_MAX_BLOCKS
;
1603 while (depth
>= 0) {
1604 if (depth
== path
->p_depth
) {
1606 if (path
[depth
].p_ext
&&
1607 path
[depth
].p_ext
!=
1608 EXT_LAST_EXTENT(path
[depth
].p_hdr
))
1609 return le32_to_cpu(path
[depth
].p_ext
[1].ee_block
);
1612 if (path
[depth
].p_idx
!=
1613 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1614 return le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1619 return EXT_MAX_BLOCKS
;
1623 * ext4_ext_next_leaf_block:
1624 * returns first allocated block from next leaf or EXT_MAX_BLOCKS
1626 static ext4_lblk_t
ext4_ext_next_leaf_block(struct ext4_ext_path
*path
)
1630 BUG_ON(path
== NULL
);
1631 depth
= path
->p_depth
;
1633 /* zero-tree has no leaf blocks at all */
1635 return EXT_MAX_BLOCKS
;
1637 /* go to index block */
1640 while (depth
>= 0) {
1641 if (path
[depth
].p_idx
!=
1642 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1643 return (ext4_lblk_t
)
1644 le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1648 return EXT_MAX_BLOCKS
;
1652 * ext4_ext_correct_indexes:
1653 * if leaf gets modified and modified extent is first in the leaf,
1654 * then we have to correct all indexes above.
1655 * TODO: do we need to correct tree in all cases?
1657 static int ext4_ext_correct_indexes(handle_t
*handle
, struct inode
*inode
,
1658 struct ext4_ext_path
*path
)
1660 struct ext4_extent_header
*eh
;
1661 int depth
= ext_depth(inode
);
1662 struct ext4_extent
*ex
;
1666 eh
= path
[depth
].p_hdr
;
1667 ex
= path
[depth
].p_ext
;
1669 if (unlikely(ex
== NULL
|| eh
== NULL
)) {
1670 EXT4_ERROR_INODE(inode
,
1671 "ex %p == NULL or eh %p == NULL", ex
, eh
);
1676 /* there is no tree at all */
1680 if (ex
!= EXT_FIRST_EXTENT(eh
)) {
1681 /* we correct tree if first leaf got modified only */
1686 * TODO: we need correction if border is smaller than current one
1689 border
= path
[depth
].p_ext
->ee_block
;
1690 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1693 path
[k
].p_idx
->ei_block
= border
;
1694 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1699 /* change all left-side indexes */
1700 if (path
[k
+1].p_idx
!= EXT_FIRST_INDEX(path
[k
+1].p_hdr
))
1702 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1705 path
[k
].p_idx
->ei_block
= border
;
1706 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1715 ext4_can_extents_be_merged(struct inode
*inode
, struct ext4_extent
*ex1
,
1716 struct ext4_extent
*ex2
)
1718 unsigned short ext1_ee_len
, ext2_ee_len
;
1721 * Make sure that both extents are initialized. We don't merge
1722 * unwritten extents so that we can be sure that end_io code has
1723 * the extent that was written properly split out and conversion to
1724 * initialized is trivial.
1726 if (ext4_ext_is_unwritten(ex1
) != ext4_ext_is_unwritten(ex2
))
1729 ext1_ee_len
= ext4_ext_get_actual_len(ex1
);
1730 ext2_ee_len
= ext4_ext_get_actual_len(ex2
);
1732 if (le32_to_cpu(ex1
->ee_block
) + ext1_ee_len
!=
1733 le32_to_cpu(ex2
->ee_block
))
1737 * To allow future support for preallocated extents to be added
1738 * as an RO_COMPAT feature, refuse to merge to extents if
1739 * this can result in the top bit of ee_len being set.
1741 if (ext1_ee_len
+ ext2_ee_len
> EXT_INIT_MAX_LEN
)
1743 if (ext4_ext_is_unwritten(ex1
) &&
1744 (ext4_test_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
) ||
1745 atomic_read(&EXT4_I(inode
)->i_unwritten
) ||
1746 (ext1_ee_len
+ ext2_ee_len
> EXT_UNWRITTEN_MAX_LEN
)))
1748 #ifdef AGGRESSIVE_TEST
1749 if (ext1_ee_len
>= 4)
1753 if (ext4_ext_pblock(ex1
) + ext1_ee_len
== ext4_ext_pblock(ex2
))
1759 * This function tries to merge the "ex" extent to the next extent in the tree.
1760 * It always tries to merge towards right. If you want to merge towards
1761 * left, pass "ex - 1" as argument instead of "ex".
1762 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1763 * 1 if they got merged.
1765 static int ext4_ext_try_to_merge_right(struct inode
*inode
,
1766 struct ext4_ext_path
*path
,
1767 struct ext4_extent
*ex
)
1769 struct ext4_extent_header
*eh
;
1770 unsigned int depth
, len
;
1771 int merge_done
= 0, unwritten
;
1773 depth
= ext_depth(inode
);
1774 BUG_ON(path
[depth
].p_hdr
== NULL
);
1775 eh
= path
[depth
].p_hdr
;
1777 while (ex
< EXT_LAST_EXTENT(eh
)) {
1778 if (!ext4_can_extents_be_merged(inode
, ex
, ex
+ 1))
1780 /* merge with next extent! */
1781 unwritten
= ext4_ext_is_unwritten(ex
);
1782 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1783 + ext4_ext_get_actual_len(ex
+ 1));
1785 ext4_ext_mark_unwritten(ex
);
1787 if (ex
+ 1 < EXT_LAST_EXTENT(eh
)) {
1788 len
= (EXT_LAST_EXTENT(eh
) - ex
- 1)
1789 * sizeof(struct ext4_extent
);
1790 memmove(ex
+ 1, ex
+ 2, len
);
1792 le16_add_cpu(&eh
->eh_entries
, -1);
1794 WARN_ON(eh
->eh_entries
== 0);
1795 if (!eh
->eh_entries
)
1796 EXT4_ERROR_INODE(inode
, "eh->eh_entries = 0!");
1803 * This function does a very simple check to see if we can collapse
1804 * an extent tree with a single extent tree leaf block into the inode.
1806 static void ext4_ext_try_to_merge_up(handle_t
*handle
,
1807 struct inode
*inode
,
1808 struct ext4_ext_path
*path
)
1811 unsigned max_root
= ext4_ext_space_root(inode
, 0);
1814 if ((path
[0].p_depth
!= 1) ||
1815 (le16_to_cpu(path
[0].p_hdr
->eh_entries
) != 1) ||
1816 (le16_to_cpu(path
[1].p_hdr
->eh_entries
) > max_root
))
1820 * We need to modify the block allocation bitmap and the block
1821 * group descriptor to release the extent tree block. If we
1822 * can't get the journal credits, give up.
1824 if (ext4_journal_extend(handle
, 2))
1828 * Copy the extent data up to the inode
1830 blk
= ext4_idx_pblock(path
[0].p_idx
);
1831 s
= le16_to_cpu(path
[1].p_hdr
->eh_entries
) *
1832 sizeof(struct ext4_extent_idx
);
1833 s
+= sizeof(struct ext4_extent_header
);
1835 path
[1].p_maxdepth
= path
[0].p_maxdepth
;
1836 memcpy(path
[0].p_hdr
, path
[1].p_hdr
, s
);
1837 path
[0].p_depth
= 0;
1838 path
[0].p_ext
= EXT_FIRST_EXTENT(path
[0].p_hdr
) +
1839 (path
[1].p_ext
- EXT_FIRST_EXTENT(path
[1].p_hdr
));
1840 path
[0].p_hdr
->eh_max
= cpu_to_le16(max_root
);
1842 brelse(path
[1].p_bh
);
1843 ext4_free_blocks(handle
, inode
, NULL
, blk
, 1,
1844 EXT4_FREE_BLOCKS_METADATA
| EXT4_FREE_BLOCKS_FORGET
);
1848 * This function tries to merge the @ex extent to neighbours in the tree.
1849 * return 1 if merge left else 0.
1851 static void ext4_ext_try_to_merge(handle_t
*handle
,
1852 struct inode
*inode
,
1853 struct ext4_ext_path
*path
,
1854 struct ext4_extent
*ex
) {
1855 struct ext4_extent_header
*eh
;
1859 depth
= ext_depth(inode
);
1860 BUG_ON(path
[depth
].p_hdr
== NULL
);
1861 eh
= path
[depth
].p_hdr
;
1863 if (ex
> EXT_FIRST_EXTENT(eh
))
1864 merge_done
= ext4_ext_try_to_merge_right(inode
, path
, ex
- 1);
1867 (void) ext4_ext_try_to_merge_right(inode
, path
, ex
);
1869 ext4_ext_try_to_merge_up(handle
, inode
, path
);
1873 * check if a portion of the "newext" extent overlaps with an
1876 * If there is an overlap discovered, it updates the length of the newext
1877 * such that there will be no overlap, and then returns 1.
1878 * If there is no overlap found, it returns 0.
1880 static unsigned int ext4_ext_check_overlap(struct ext4_sb_info
*sbi
,
1881 struct inode
*inode
,
1882 struct ext4_extent
*newext
,
1883 struct ext4_ext_path
*path
)
1886 unsigned int depth
, len1
;
1887 unsigned int ret
= 0;
1889 b1
= le32_to_cpu(newext
->ee_block
);
1890 len1
= ext4_ext_get_actual_len(newext
);
1891 depth
= ext_depth(inode
);
1892 if (!path
[depth
].p_ext
)
1894 b2
= EXT4_LBLK_CMASK(sbi
, le32_to_cpu(path
[depth
].p_ext
->ee_block
));
1897 * get the next allocated block if the extent in the path
1898 * is before the requested block(s)
1901 b2
= ext4_ext_next_allocated_block(path
);
1902 if (b2
== EXT_MAX_BLOCKS
)
1904 b2
= EXT4_LBLK_CMASK(sbi
, b2
);
1907 /* check for wrap through zero on extent logical start block*/
1908 if (b1
+ len1
< b1
) {
1909 len1
= EXT_MAX_BLOCKS
- b1
;
1910 newext
->ee_len
= cpu_to_le16(len1
);
1914 /* check for overlap */
1915 if (b1
+ len1
> b2
) {
1916 newext
->ee_len
= cpu_to_le16(b2
- b1
);
1924 * ext4_ext_insert_extent:
1925 * tries to merge requsted extent into the existing extent or
1926 * inserts requested extent as new one into the tree,
1927 * creating new leaf in the no-space case.
1929 int ext4_ext_insert_extent(handle_t
*handle
, struct inode
*inode
,
1930 struct ext4_ext_path
**ppath
,
1931 struct ext4_extent
*newext
, int gb_flags
)
1933 struct ext4_ext_path
*path
= *ppath
;
1934 struct ext4_extent_header
*eh
;
1935 struct ext4_extent
*ex
, *fex
;
1936 struct ext4_extent
*nearex
; /* nearest extent */
1937 struct ext4_ext_path
*npath
= NULL
;
1938 int depth
, len
, err
;
1940 int mb_flags
= 0, unwritten
;
1942 if (gb_flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
1943 mb_flags
|= EXT4_MB_DELALLOC_RESERVED
;
1944 if (unlikely(ext4_ext_get_actual_len(newext
) == 0)) {
1945 EXT4_ERROR_INODE(inode
, "ext4_ext_get_actual_len(newext) == 0");
1948 depth
= ext_depth(inode
);
1949 ex
= path
[depth
].p_ext
;
1950 eh
= path
[depth
].p_hdr
;
1951 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
1952 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
1956 /* try to insert block into found extent and return */
1957 if (ex
&& !(gb_flags
& EXT4_GET_BLOCKS_PRE_IO
)) {
1960 * Try to see whether we should rather test the extent on
1961 * right from ex, or from the left of ex. This is because
1962 * ext4_find_extent() can return either extent on the
1963 * left, or on the right from the searched position. This
1964 * will make merging more effective.
1966 if (ex
< EXT_LAST_EXTENT(eh
) &&
1967 (le32_to_cpu(ex
->ee_block
) +
1968 ext4_ext_get_actual_len(ex
) <
1969 le32_to_cpu(newext
->ee_block
))) {
1972 } else if ((ex
> EXT_FIRST_EXTENT(eh
)) &&
1973 (le32_to_cpu(newext
->ee_block
) +
1974 ext4_ext_get_actual_len(newext
) <
1975 le32_to_cpu(ex
->ee_block
)))
1978 /* Try to append newex to the ex */
1979 if (ext4_can_extents_be_merged(inode
, ex
, newext
)) {
1980 ext_debug("append [%d]%d block to %u:[%d]%d"
1982 ext4_ext_is_unwritten(newext
),
1983 ext4_ext_get_actual_len(newext
),
1984 le32_to_cpu(ex
->ee_block
),
1985 ext4_ext_is_unwritten(ex
),
1986 ext4_ext_get_actual_len(ex
),
1987 ext4_ext_pblock(ex
));
1988 err
= ext4_ext_get_access(handle
, inode
,
1992 unwritten
= ext4_ext_is_unwritten(ex
);
1993 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1994 + ext4_ext_get_actual_len(newext
));
1996 ext4_ext_mark_unwritten(ex
);
1997 eh
= path
[depth
].p_hdr
;
2003 /* Try to prepend newex to the ex */
2004 if (ext4_can_extents_be_merged(inode
, newext
, ex
)) {
2005 ext_debug("prepend %u[%d]%d block to %u:[%d]%d"
2007 le32_to_cpu(newext
->ee_block
),
2008 ext4_ext_is_unwritten(newext
),
2009 ext4_ext_get_actual_len(newext
),
2010 le32_to_cpu(ex
->ee_block
),
2011 ext4_ext_is_unwritten(ex
),
2012 ext4_ext_get_actual_len(ex
),
2013 ext4_ext_pblock(ex
));
2014 err
= ext4_ext_get_access(handle
, inode
,
2019 unwritten
= ext4_ext_is_unwritten(ex
);
2020 ex
->ee_block
= newext
->ee_block
;
2021 ext4_ext_store_pblock(ex
, ext4_ext_pblock(newext
));
2022 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
2023 + ext4_ext_get_actual_len(newext
));
2025 ext4_ext_mark_unwritten(ex
);
2026 eh
= path
[depth
].p_hdr
;
2032 depth
= ext_depth(inode
);
2033 eh
= path
[depth
].p_hdr
;
2034 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
))
2037 /* probably next leaf has space for us? */
2038 fex
= EXT_LAST_EXTENT(eh
);
2039 next
= EXT_MAX_BLOCKS
;
2040 if (le32_to_cpu(newext
->ee_block
) > le32_to_cpu(fex
->ee_block
))
2041 next
= ext4_ext_next_leaf_block(path
);
2042 if (next
!= EXT_MAX_BLOCKS
) {
2043 ext_debug("next leaf block - %u\n", next
);
2044 BUG_ON(npath
!= NULL
);
2045 npath
= ext4_find_extent(inode
, next
, NULL
, 0);
2047 return PTR_ERR(npath
);
2048 BUG_ON(npath
->p_depth
!= path
->p_depth
);
2049 eh
= npath
[depth
].p_hdr
;
2050 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
)) {
2051 ext_debug("next leaf isn't full(%d)\n",
2052 le16_to_cpu(eh
->eh_entries
));
2056 ext_debug("next leaf has no free space(%d,%d)\n",
2057 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
2061 * There is no free space in the found leaf.
2062 * We're gonna add a new leaf in the tree.
2064 if (gb_flags
& EXT4_GET_BLOCKS_METADATA_NOFAIL
)
2065 mb_flags
|= EXT4_MB_USE_RESERVED
;
2066 err
= ext4_ext_create_new_leaf(handle
, inode
, mb_flags
, gb_flags
,
2070 depth
= ext_depth(inode
);
2071 eh
= path
[depth
].p_hdr
;
2074 nearex
= path
[depth
].p_ext
;
2076 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2081 /* there is no extent in this leaf, create first one */
2082 ext_debug("first extent in the leaf: %u:%llu:[%d]%d\n",
2083 le32_to_cpu(newext
->ee_block
),
2084 ext4_ext_pblock(newext
),
2085 ext4_ext_is_unwritten(newext
),
2086 ext4_ext_get_actual_len(newext
));
2087 nearex
= EXT_FIRST_EXTENT(eh
);
2089 if (le32_to_cpu(newext
->ee_block
)
2090 > le32_to_cpu(nearex
->ee_block
)) {
2092 ext_debug("insert %u:%llu:[%d]%d before: "
2094 le32_to_cpu(newext
->ee_block
),
2095 ext4_ext_pblock(newext
),
2096 ext4_ext_is_unwritten(newext
),
2097 ext4_ext_get_actual_len(newext
),
2102 BUG_ON(newext
->ee_block
== nearex
->ee_block
);
2103 ext_debug("insert %u:%llu:[%d]%d after: "
2105 le32_to_cpu(newext
->ee_block
),
2106 ext4_ext_pblock(newext
),
2107 ext4_ext_is_unwritten(newext
),
2108 ext4_ext_get_actual_len(newext
),
2111 len
= EXT_LAST_EXTENT(eh
) - nearex
+ 1;
2113 ext_debug("insert %u:%llu:[%d]%d: "
2114 "move %d extents from 0x%p to 0x%p\n",
2115 le32_to_cpu(newext
->ee_block
),
2116 ext4_ext_pblock(newext
),
2117 ext4_ext_is_unwritten(newext
),
2118 ext4_ext_get_actual_len(newext
),
2119 len
, nearex
, nearex
+ 1);
2120 memmove(nearex
+ 1, nearex
,
2121 len
* sizeof(struct ext4_extent
));
2125 le16_add_cpu(&eh
->eh_entries
, 1);
2126 path
[depth
].p_ext
= nearex
;
2127 nearex
->ee_block
= newext
->ee_block
;
2128 ext4_ext_store_pblock(nearex
, ext4_ext_pblock(newext
));
2129 nearex
->ee_len
= newext
->ee_len
;
2132 /* try to merge extents */
2133 if (!(gb_flags
& EXT4_GET_BLOCKS_PRE_IO
))
2134 ext4_ext_try_to_merge(handle
, inode
, path
, nearex
);
2137 /* time to correct all indexes above */
2138 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2142 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
2145 ext4_ext_drop_refs(npath
);
2150 static int ext4_fill_fiemap_extents(struct inode
*inode
,
2151 ext4_lblk_t block
, ext4_lblk_t num
,
2152 struct fiemap_extent_info
*fieinfo
)
2154 struct ext4_ext_path
*path
= NULL
;
2155 struct ext4_extent
*ex
;
2156 struct extent_status es
;
2157 ext4_lblk_t next
, next_del
, start
= 0, end
= 0;
2158 ext4_lblk_t last
= block
+ num
;
2159 int exists
, depth
= 0, err
= 0;
2160 unsigned int flags
= 0;
2161 unsigned char blksize_bits
= inode
->i_sb
->s_blocksize_bits
;
2163 while (block
< last
&& block
!= EXT_MAX_BLOCKS
) {
2165 /* find extent for this block */
2166 down_read(&EXT4_I(inode
)->i_data_sem
);
2168 path
= ext4_find_extent(inode
, block
, &path
, 0);
2170 up_read(&EXT4_I(inode
)->i_data_sem
);
2171 err
= PTR_ERR(path
);
2176 depth
= ext_depth(inode
);
2177 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
2178 up_read(&EXT4_I(inode
)->i_data_sem
);
2179 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
2183 ex
= path
[depth
].p_ext
;
2184 next
= ext4_ext_next_allocated_block(path
);
2189 /* there is no extent yet, so try to allocate
2190 * all requested space */
2193 } else if (le32_to_cpu(ex
->ee_block
) > block
) {
2194 /* need to allocate space before found extent */
2196 end
= le32_to_cpu(ex
->ee_block
);
2197 if (block
+ num
< end
)
2199 } else if (block
>= le32_to_cpu(ex
->ee_block
)
2200 + ext4_ext_get_actual_len(ex
)) {
2201 /* need to allocate space after found extent */
2206 } else if (block
>= le32_to_cpu(ex
->ee_block
)) {
2208 * some part of requested space is covered
2212 end
= le32_to_cpu(ex
->ee_block
)
2213 + ext4_ext_get_actual_len(ex
);
2214 if (block
+ num
< end
)
2220 BUG_ON(end
<= start
);
2224 es
.es_len
= end
- start
;
2227 es
.es_lblk
= le32_to_cpu(ex
->ee_block
);
2228 es
.es_len
= ext4_ext_get_actual_len(ex
);
2229 es
.es_pblk
= ext4_ext_pblock(ex
);
2230 if (ext4_ext_is_unwritten(ex
))
2231 flags
|= FIEMAP_EXTENT_UNWRITTEN
;
2235 * Find delayed extent and update es accordingly. We call
2236 * it even in !exists case to find out whether es is the
2237 * last existing extent or not.
2239 next_del
= ext4_find_delayed_extent(inode
, &es
);
2240 if (!exists
&& next_del
) {
2242 flags
|= (FIEMAP_EXTENT_DELALLOC
|
2243 FIEMAP_EXTENT_UNKNOWN
);
2245 up_read(&EXT4_I(inode
)->i_data_sem
);
2247 if (unlikely(es
.es_len
== 0)) {
2248 EXT4_ERROR_INODE(inode
, "es.es_len == 0");
2254 * This is possible iff next == next_del == EXT_MAX_BLOCKS.
2255 * we need to check next == EXT_MAX_BLOCKS because it is
2256 * possible that an extent is with unwritten and delayed
2257 * status due to when an extent is delayed allocated and
2258 * is allocated by fallocate status tree will track both of
2261 * So we could return a unwritten and delayed extent, and
2262 * its block is equal to 'next'.
2264 if (next
== next_del
&& next
== EXT_MAX_BLOCKS
) {
2265 flags
|= FIEMAP_EXTENT_LAST
;
2266 if (unlikely(next_del
!= EXT_MAX_BLOCKS
||
2267 next
!= EXT_MAX_BLOCKS
)) {
2268 EXT4_ERROR_INODE(inode
,
2269 "next extent == %u, next "
2270 "delalloc extent = %u",
2278 err
= fiemap_fill_next_extent(fieinfo
,
2279 (__u64
)es
.es_lblk
<< blksize_bits
,
2280 (__u64
)es
.es_pblk
<< blksize_bits
,
2281 (__u64
)es
.es_len
<< blksize_bits
,
2291 block
= es
.es_lblk
+ es
.es_len
;
2294 ext4_ext_drop_refs(path
);
2300 * ext4_ext_put_gap_in_cache:
2301 * calculate boundaries of the gap that the requested block fits into
2302 * and cache this gap
2305 ext4_ext_put_gap_in_cache(struct inode
*inode
, struct ext4_ext_path
*path
,
2308 int depth
= ext_depth(inode
);
2309 unsigned long len
= 0;
2310 ext4_lblk_t lblock
= 0;
2311 struct ext4_extent
*ex
;
2313 ex
= path
[depth
].p_ext
;
2316 * there is no extent yet, so gap is [0;-] and we
2319 ext_debug("cache gap(whole file):");
2320 } else if (block
< le32_to_cpu(ex
->ee_block
)) {
2322 len
= le32_to_cpu(ex
->ee_block
) - block
;
2323 ext_debug("cache gap(before): %u [%u:%u]",
2325 le32_to_cpu(ex
->ee_block
),
2326 ext4_ext_get_actual_len(ex
));
2327 if (!ext4_find_delalloc_range(inode
, lblock
, lblock
+ len
- 1))
2328 ext4_es_insert_extent(inode
, lblock
, len
, ~0,
2329 EXTENT_STATUS_HOLE
);
2330 } else if (block
>= le32_to_cpu(ex
->ee_block
)
2331 + ext4_ext_get_actual_len(ex
)) {
2333 lblock
= le32_to_cpu(ex
->ee_block
)
2334 + ext4_ext_get_actual_len(ex
);
2336 next
= ext4_ext_next_allocated_block(path
);
2337 ext_debug("cache gap(after): [%u:%u] %u",
2338 le32_to_cpu(ex
->ee_block
),
2339 ext4_ext_get_actual_len(ex
),
2341 BUG_ON(next
== lblock
);
2342 len
= next
- lblock
;
2343 if (!ext4_find_delalloc_range(inode
, lblock
, lblock
+ len
- 1))
2344 ext4_es_insert_extent(inode
, lblock
, len
, ~0,
2345 EXTENT_STATUS_HOLE
);
2350 ext_debug(" -> %u:%lu\n", lblock
, len
);
2355 * removes index from the index block.
2357 static int ext4_ext_rm_idx(handle_t
*handle
, struct inode
*inode
,
2358 struct ext4_ext_path
*path
, int depth
)
2363 /* free index block */
2365 path
= path
+ depth
;
2366 leaf
= ext4_idx_pblock(path
->p_idx
);
2367 if (unlikely(path
->p_hdr
->eh_entries
== 0)) {
2368 EXT4_ERROR_INODE(inode
, "path->p_hdr->eh_entries == 0");
2371 err
= ext4_ext_get_access(handle
, inode
, path
);
2375 if (path
->p_idx
!= EXT_LAST_INDEX(path
->p_hdr
)) {
2376 int len
= EXT_LAST_INDEX(path
->p_hdr
) - path
->p_idx
;
2377 len
*= sizeof(struct ext4_extent_idx
);
2378 memmove(path
->p_idx
, path
->p_idx
+ 1, len
);
2381 le16_add_cpu(&path
->p_hdr
->eh_entries
, -1);
2382 err
= ext4_ext_dirty(handle
, inode
, path
);
2385 ext_debug("index is empty, remove it, free block %llu\n", leaf
);
2386 trace_ext4_ext_rm_idx(inode
, leaf
);
2388 ext4_free_blocks(handle
, inode
, NULL
, leaf
, 1,
2389 EXT4_FREE_BLOCKS_METADATA
| EXT4_FREE_BLOCKS_FORGET
);
2391 while (--depth
>= 0) {
2392 if (path
->p_idx
!= EXT_FIRST_INDEX(path
->p_hdr
))
2395 err
= ext4_ext_get_access(handle
, inode
, path
);
2398 path
->p_idx
->ei_block
= (path
+1)->p_idx
->ei_block
;
2399 err
= ext4_ext_dirty(handle
, inode
, path
);
2407 * ext4_ext_calc_credits_for_single_extent:
2408 * This routine returns max. credits that needed to insert an extent
2409 * to the extent tree.
2410 * When pass the actual path, the caller should calculate credits
2413 int ext4_ext_calc_credits_for_single_extent(struct inode
*inode
, int nrblocks
,
2414 struct ext4_ext_path
*path
)
2417 int depth
= ext_depth(inode
);
2420 /* probably there is space in leaf? */
2421 if (le16_to_cpu(path
[depth
].p_hdr
->eh_entries
)
2422 < le16_to_cpu(path
[depth
].p_hdr
->eh_max
)) {
2425 * There are some space in the leaf tree, no
2426 * need to account for leaf block credit
2428 * bitmaps and block group descriptor blocks
2429 * and other metadata blocks still need to be
2432 /* 1 bitmap, 1 block group descriptor */
2433 ret
= 2 + EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
2438 return ext4_chunk_trans_blocks(inode
, nrblocks
);
2442 * How many index/leaf blocks need to change/allocate to add @extents extents?
2444 * If we add a single extent, then in the worse case, each tree level
2445 * index/leaf need to be changed in case of the tree split.
2447 * If more extents are inserted, they could cause the whole tree split more
2448 * than once, but this is really rare.
2450 int ext4_ext_index_trans_blocks(struct inode
*inode
, int extents
)
2455 /* If we are converting the inline data, only one is needed here. */
2456 if (ext4_has_inline_data(inode
))
2459 depth
= ext_depth(inode
);
2469 static inline int get_default_free_blocks_flags(struct inode
*inode
)
2471 if (S_ISDIR(inode
->i_mode
) || S_ISLNK(inode
->i_mode
))
2472 return EXT4_FREE_BLOCKS_METADATA
| EXT4_FREE_BLOCKS_FORGET
;
2473 else if (ext4_should_journal_data(inode
))
2474 return EXT4_FREE_BLOCKS_FORGET
;
2478 static int ext4_remove_blocks(handle_t
*handle
, struct inode
*inode
,
2479 struct ext4_extent
*ex
,
2480 long long *partial_cluster
,
2481 ext4_lblk_t from
, ext4_lblk_t to
)
2483 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2484 unsigned short ee_len
= ext4_ext_get_actual_len(ex
);
2486 int flags
= get_default_free_blocks_flags(inode
);
2489 * For bigalloc file systems, we never free a partial cluster
2490 * at the beginning of the extent. Instead, we make a note
2491 * that we tried freeing the cluster, and check to see if we
2492 * need to free it on a subsequent call to ext4_remove_blocks,
2493 * or at the end of the ext4_truncate() operation.
2495 flags
|= EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER
;
2497 trace_ext4_remove_blocks(inode
, ex
, from
, to
, *partial_cluster
);
2499 * If we have a partial cluster, and it's different from the
2500 * cluster of the last block, we need to explicitly free the
2501 * partial cluster here.
2503 pblk
= ext4_ext_pblock(ex
) + ee_len
- 1;
2504 if ((*partial_cluster
> 0) &&
2505 (EXT4_B2C(sbi
, pblk
) != *partial_cluster
)) {
2506 ext4_free_blocks(handle
, inode
, NULL
,
2507 EXT4_C2B(sbi
, *partial_cluster
),
2508 sbi
->s_cluster_ratio
, flags
);
2509 *partial_cluster
= 0;
2512 #ifdef EXTENTS_STATS
2514 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2515 spin_lock(&sbi
->s_ext_stats_lock
);
2516 sbi
->s_ext_blocks
+= ee_len
;
2517 sbi
->s_ext_extents
++;
2518 if (ee_len
< sbi
->s_ext_min
)
2519 sbi
->s_ext_min
= ee_len
;
2520 if (ee_len
> sbi
->s_ext_max
)
2521 sbi
->s_ext_max
= ee_len
;
2522 if (ext_depth(inode
) > sbi
->s_depth_max
)
2523 sbi
->s_depth_max
= ext_depth(inode
);
2524 spin_unlock(&sbi
->s_ext_stats_lock
);
2527 if (from
>= le32_to_cpu(ex
->ee_block
)
2528 && to
== le32_to_cpu(ex
->ee_block
) + ee_len
- 1) {
2531 unsigned int unaligned
;
2533 num
= le32_to_cpu(ex
->ee_block
) + ee_len
- from
;
2534 pblk
= ext4_ext_pblock(ex
) + ee_len
- num
;
2536 * Usually we want to free partial cluster at the end of the
2537 * extent, except for the situation when the cluster is still
2538 * used by any other extent (partial_cluster is negative).
2540 if (*partial_cluster
< 0 &&
2541 -(*partial_cluster
) == EXT4_B2C(sbi
, pblk
+ num
- 1))
2542 flags
|= EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER
;
2544 ext_debug("free last %u blocks starting %llu partial %lld\n",
2545 num
, pblk
, *partial_cluster
);
2546 ext4_free_blocks(handle
, inode
, NULL
, pblk
, num
, flags
);
2548 * If the block range to be freed didn't start at the
2549 * beginning of a cluster, and we removed the entire
2550 * extent and the cluster is not used by any other extent,
2551 * save the partial cluster here, since we might need to
2552 * delete if we determine that the truncate operation has
2553 * removed all of the blocks in the cluster.
2555 * On the other hand, if we did not manage to free the whole
2556 * extent, we have to mark the cluster as used (store negative
2557 * cluster number in partial_cluster).
2559 unaligned
= EXT4_PBLK_COFF(sbi
, pblk
);
2560 if (unaligned
&& (ee_len
== num
) &&
2561 (*partial_cluster
!= -((long long)EXT4_B2C(sbi
, pblk
))))
2562 *partial_cluster
= EXT4_B2C(sbi
, pblk
);
2564 *partial_cluster
= -((long long)EXT4_B2C(sbi
, pblk
));
2565 else if (*partial_cluster
> 0)
2566 *partial_cluster
= 0;
2568 ext4_error(sbi
->s_sb
, "strange request: removal(2) "
2569 "%u-%u from %u:%u\n",
2570 from
, to
, le32_to_cpu(ex
->ee_block
), ee_len
);
2576 * ext4_ext_rm_leaf() Removes the extents associated with the
2577 * blocks appearing between "start" and "end", and splits the extents
2578 * if "start" and "end" appear in the same extent
2580 * @handle: The journal handle
2581 * @inode: The files inode
2582 * @path: The path to the leaf
2583 * @partial_cluster: The cluster which we'll have to free if all extents
2584 * has been released from it. It gets negative in case
2585 * that the cluster is still used.
2586 * @start: The first block to remove
2587 * @end: The last block to remove
2590 ext4_ext_rm_leaf(handle_t
*handle
, struct inode
*inode
,
2591 struct ext4_ext_path
*path
,
2592 long long *partial_cluster
,
2593 ext4_lblk_t start
, ext4_lblk_t end
)
2595 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2596 int err
= 0, correct_index
= 0;
2597 int depth
= ext_depth(inode
), credits
;
2598 struct ext4_extent_header
*eh
;
2601 ext4_lblk_t ex_ee_block
;
2602 unsigned short ex_ee_len
;
2603 unsigned unwritten
= 0;
2604 struct ext4_extent
*ex
;
2607 /* the header must be checked already in ext4_ext_remove_space() */
2608 ext_debug("truncate since %u in leaf to %u\n", start
, end
);
2609 if (!path
[depth
].p_hdr
)
2610 path
[depth
].p_hdr
= ext_block_hdr(path
[depth
].p_bh
);
2611 eh
= path
[depth
].p_hdr
;
2612 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
2613 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
2616 /* find where to start removing */
2617 ex
= path
[depth
].p_ext
;
2619 ex
= EXT_LAST_EXTENT(eh
);
2621 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2622 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2625 * If we're starting with an extent other than the last one in the
2626 * node, we need to see if it shares a cluster with the extent to
2627 * the right (towards the end of the file). If its leftmost cluster
2628 * is this extent's rightmost cluster and it is not cluster aligned,
2629 * we'll mark it as a partial that is not to be deallocated.
2632 if (ex
!= EXT_LAST_EXTENT(eh
)) {
2633 ext4_fsblk_t current_pblk
, right_pblk
;
2634 long long current_cluster
, right_cluster
;
2636 current_pblk
= ext4_ext_pblock(ex
) + ex_ee_len
- 1;
2637 current_cluster
= (long long)EXT4_B2C(sbi
, current_pblk
);
2638 right_pblk
= ext4_ext_pblock(ex
+ 1);
2639 right_cluster
= (long long)EXT4_B2C(sbi
, right_pblk
);
2640 if (current_cluster
== right_cluster
&&
2641 EXT4_PBLK_COFF(sbi
, right_pblk
))
2642 *partial_cluster
= -right_cluster
;
2645 trace_ext4_ext_rm_leaf(inode
, start
, ex
, *partial_cluster
);
2647 while (ex
>= EXT_FIRST_EXTENT(eh
) &&
2648 ex_ee_block
+ ex_ee_len
> start
) {
2650 if (ext4_ext_is_unwritten(ex
))
2655 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block
,
2656 unwritten
, ex_ee_len
);
2657 path
[depth
].p_ext
= ex
;
2659 a
= ex_ee_block
> start
? ex_ee_block
: start
;
2660 b
= ex_ee_block
+ex_ee_len
- 1 < end
?
2661 ex_ee_block
+ex_ee_len
- 1 : end
;
2663 ext_debug(" border %u:%u\n", a
, b
);
2665 /* If this extent is beyond the end of the hole, skip it */
2666 if (end
< ex_ee_block
) {
2668 * We're going to skip this extent and move to another,
2669 * so if this extent is not cluster aligned we have
2670 * to mark the current cluster as used to avoid
2671 * accidentally freeing it later on
2673 pblk
= ext4_ext_pblock(ex
);
2674 if (EXT4_PBLK_COFF(sbi
, pblk
))
2676 -((long long)EXT4_B2C(sbi
, pblk
));
2678 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2679 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2681 } else if (b
!= ex_ee_block
+ ex_ee_len
- 1) {
2682 EXT4_ERROR_INODE(inode
,
2683 "can not handle truncate %u:%u "
2685 start
, end
, ex_ee_block
,
2686 ex_ee_block
+ ex_ee_len
- 1);
2689 } else if (a
!= ex_ee_block
) {
2690 /* remove tail of the extent */
2691 num
= a
- ex_ee_block
;
2693 /* remove whole extent: excellent! */
2697 * 3 for leaf, sb, and inode plus 2 (bmap and group
2698 * descriptor) for each block group; assume two block
2699 * groups plus ex_ee_len/blocks_per_block_group for
2702 credits
= 7 + 2*(ex_ee_len
/EXT4_BLOCKS_PER_GROUP(inode
->i_sb
));
2703 if (ex
== EXT_FIRST_EXTENT(eh
)) {
2705 credits
+= (ext_depth(inode
)) + 1;
2707 credits
+= EXT4_MAXQUOTAS_TRANS_BLOCKS(inode
->i_sb
);
2709 err
= ext4_ext_truncate_extend_restart(handle
, inode
, credits
);
2713 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2717 err
= ext4_remove_blocks(handle
, inode
, ex
, partial_cluster
,
2723 /* this extent is removed; mark slot entirely unused */
2724 ext4_ext_store_pblock(ex
, 0);
2726 ex
->ee_len
= cpu_to_le16(num
);
2728 * Do not mark unwritten if all the blocks in the
2729 * extent have been removed.
2731 if (unwritten
&& num
)
2732 ext4_ext_mark_unwritten(ex
);
2734 * If the extent was completely released,
2735 * we need to remove it from the leaf
2738 if (end
!= EXT_MAX_BLOCKS
- 1) {
2740 * For hole punching, we need to scoot all the
2741 * extents up when an extent is removed so that
2742 * we dont have blank extents in the middle
2744 memmove(ex
, ex
+1, (EXT_LAST_EXTENT(eh
) - ex
) *
2745 sizeof(struct ext4_extent
));
2747 /* Now get rid of the one at the end */
2748 memset(EXT_LAST_EXTENT(eh
), 0,
2749 sizeof(struct ext4_extent
));
2751 le16_add_cpu(&eh
->eh_entries
, -1);
2752 } else if (*partial_cluster
> 0)
2753 *partial_cluster
= 0;
2755 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2759 ext_debug("new extent: %u:%u:%llu\n", ex_ee_block
, num
,
2760 ext4_ext_pblock(ex
));
2762 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2763 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2766 if (correct_index
&& eh
->eh_entries
)
2767 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2770 * If there's a partial cluster and at least one extent remains in
2771 * the leaf, free the partial cluster if it isn't shared with the
2772 * current extent. If there's a partial cluster and no extents
2773 * remain in the leaf, it can't be freed here. It can only be
2774 * freed when it's possible to determine if it's not shared with
2775 * any other extent - when the next leaf is processed or when space
2776 * removal is complete.
2778 if (*partial_cluster
> 0 && eh
->eh_entries
&&
2779 (EXT4_B2C(sbi
, ext4_ext_pblock(ex
) + ex_ee_len
- 1) !=
2780 *partial_cluster
)) {
2781 int flags
= get_default_free_blocks_flags(inode
);
2783 ext4_free_blocks(handle
, inode
, NULL
,
2784 EXT4_C2B(sbi
, *partial_cluster
),
2785 sbi
->s_cluster_ratio
, flags
);
2786 *partial_cluster
= 0;
2789 /* if this leaf is free, then we should
2790 * remove it from index block above */
2791 if (err
== 0 && eh
->eh_entries
== 0 && path
[depth
].p_bh
!= NULL
)
2792 err
= ext4_ext_rm_idx(handle
, inode
, path
, depth
);
2799 * ext4_ext_more_to_rm:
2800 * returns 1 if current index has to be freed (even partial)
2803 ext4_ext_more_to_rm(struct ext4_ext_path
*path
)
2805 BUG_ON(path
->p_idx
== NULL
);
2807 if (path
->p_idx
< EXT_FIRST_INDEX(path
->p_hdr
))
2811 * if truncate on deeper level happened, it wasn't partial,
2812 * so we have to consider current index for truncation
2814 if (le16_to_cpu(path
->p_hdr
->eh_entries
) == path
->p_block
)
2819 int ext4_ext_remove_space(struct inode
*inode
, ext4_lblk_t start
,
2822 struct super_block
*sb
= inode
->i_sb
;
2823 int depth
= ext_depth(inode
);
2824 struct ext4_ext_path
*path
= NULL
;
2825 long long partial_cluster
= 0;
2829 ext_debug("truncate since %u to %u\n", start
, end
);
2831 /* probably first extent we're gonna free will be last in block */
2832 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, depth
+ 1);
2834 return PTR_ERR(handle
);
2837 trace_ext4_ext_remove_space(inode
, start
, end
, depth
);
2840 * Check if we are removing extents inside the extent tree. If that
2841 * is the case, we are going to punch a hole inside the extent tree
2842 * so we have to check whether we need to split the extent covering
2843 * the last block to remove so we can easily remove the part of it
2844 * in ext4_ext_rm_leaf().
2846 if (end
< EXT_MAX_BLOCKS
- 1) {
2847 struct ext4_extent
*ex
;
2848 ext4_lblk_t ee_block
;
2850 /* find extent for this block */
2851 path
= ext4_find_extent(inode
, end
, NULL
, EXT4_EX_NOCACHE
);
2853 ext4_journal_stop(handle
);
2854 return PTR_ERR(path
);
2856 depth
= ext_depth(inode
);
2857 /* Leaf not may not exist only if inode has no blocks at all */
2858 ex
= path
[depth
].p_ext
;
2861 EXT4_ERROR_INODE(inode
,
2862 "path[%d].p_hdr == NULL",
2869 ee_block
= le32_to_cpu(ex
->ee_block
);
2872 * See if the last block is inside the extent, if so split
2873 * the extent at 'end' block so we can easily remove the
2874 * tail of the first part of the split extent in
2875 * ext4_ext_rm_leaf().
2877 if (end
>= ee_block
&&
2878 end
< ee_block
+ ext4_ext_get_actual_len(ex
) - 1) {
2880 * Split the extent in two so that 'end' is the last
2881 * block in the first new extent. Also we should not
2882 * fail removing space due to ENOSPC so try to use
2883 * reserved block if that happens.
2885 err
= ext4_force_split_extent_at(handle
, inode
, &path
,
2892 * We start scanning from right side, freeing all the blocks
2893 * after i_size and walking into the tree depth-wise.
2895 depth
= ext_depth(inode
);
2900 le16_to_cpu(path
[k
].p_hdr
->eh_entries
)+1;
2902 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 1),
2905 ext4_journal_stop(handle
);
2908 path
[0].p_maxdepth
= path
[0].p_depth
= depth
;
2909 path
[0].p_hdr
= ext_inode_hdr(inode
);
2912 if (ext4_ext_check(inode
, path
[0].p_hdr
, depth
, 0)) {
2919 while (i
>= 0 && err
== 0) {
2921 /* this is leaf block */
2922 err
= ext4_ext_rm_leaf(handle
, inode
, path
,
2923 &partial_cluster
, start
,
2925 /* root level has p_bh == NULL, brelse() eats this */
2926 brelse(path
[i
].p_bh
);
2927 path
[i
].p_bh
= NULL
;
2932 /* this is index block */
2933 if (!path
[i
].p_hdr
) {
2934 ext_debug("initialize header\n");
2935 path
[i
].p_hdr
= ext_block_hdr(path
[i
].p_bh
);
2938 if (!path
[i
].p_idx
) {
2939 /* this level hasn't been touched yet */
2940 path
[i
].p_idx
= EXT_LAST_INDEX(path
[i
].p_hdr
);
2941 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
)+1;
2942 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2944 le16_to_cpu(path
[i
].p_hdr
->eh_entries
));
2946 /* we were already here, see at next index */
2950 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2951 i
, EXT_FIRST_INDEX(path
[i
].p_hdr
),
2953 if (ext4_ext_more_to_rm(path
+ i
)) {
2954 struct buffer_head
*bh
;
2955 /* go to the next level */
2956 ext_debug("move to level %d (block %llu)\n",
2957 i
+ 1, ext4_idx_pblock(path
[i
].p_idx
));
2958 memset(path
+ i
+ 1, 0, sizeof(*path
));
2959 bh
= read_extent_tree_block(inode
,
2960 ext4_idx_pblock(path
[i
].p_idx
), depth
- i
- 1,
2963 /* should we reset i_size? */
2967 /* Yield here to deal with large extent trees.
2968 * Should be a no-op if we did IO above. */
2970 if (WARN_ON(i
+ 1 > depth
)) {
2974 path
[i
+ 1].p_bh
= bh
;
2976 /* save actual number of indexes since this
2977 * number is changed at the next iteration */
2978 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
);
2981 /* we finished processing this index, go up */
2982 if (path
[i
].p_hdr
->eh_entries
== 0 && i
> 0) {
2983 /* index is empty, remove it;
2984 * handle must be already prepared by the
2985 * truncatei_leaf() */
2986 err
= ext4_ext_rm_idx(handle
, inode
, path
, i
);
2988 /* root level has p_bh == NULL, brelse() eats this */
2989 brelse(path
[i
].p_bh
);
2990 path
[i
].p_bh
= NULL
;
2992 ext_debug("return to level %d\n", i
);
2996 trace_ext4_ext_remove_space_done(inode
, start
, end
, depth
,
2997 partial_cluster
, path
->p_hdr
->eh_entries
);
2999 /* If we still have something in the partial cluster and we have removed
3000 * even the first extent, then we should free the blocks in the partial
3001 * cluster as well. */
3002 if (partial_cluster
> 0 && path
->p_hdr
->eh_entries
== 0) {
3003 int flags
= get_default_free_blocks_flags(inode
);
3005 ext4_free_blocks(handle
, inode
, NULL
,
3006 EXT4_C2B(EXT4_SB(sb
), partial_cluster
),
3007 EXT4_SB(sb
)->s_cluster_ratio
, flags
);
3008 partial_cluster
= 0;
3011 /* TODO: flexible tree reduction should be here */
3012 if (path
->p_hdr
->eh_entries
== 0) {
3014 * truncate to zero freed all the tree,
3015 * so we need to correct eh_depth
3017 err
= ext4_ext_get_access(handle
, inode
, path
);
3019 ext_inode_hdr(inode
)->eh_depth
= 0;
3020 ext_inode_hdr(inode
)->eh_max
=
3021 cpu_to_le16(ext4_ext_space_root(inode
, 0));
3022 err
= ext4_ext_dirty(handle
, inode
, path
);
3026 ext4_ext_drop_refs(path
);
3031 ext4_journal_stop(handle
);
3037 * called at mount time
3039 void ext4_ext_init(struct super_block
*sb
)
3042 * possible initialization would be here
3045 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
)) {
3046 #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
3047 printk(KERN_INFO
"EXT4-fs: file extents enabled"
3048 #ifdef AGGRESSIVE_TEST
3049 ", aggressive tests"
3051 #ifdef CHECK_BINSEARCH
3054 #ifdef EXTENTS_STATS
3059 #ifdef EXTENTS_STATS
3060 spin_lock_init(&EXT4_SB(sb
)->s_ext_stats_lock
);
3061 EXT4_SB(sb
)->s_ext_min
= 1 << 30;
3062 EXT4_SB(sb
)->s_ext_max
= 0;
3068 * called at umount time
3070 void ext4_ext_release(struct super_block
*sb
)
3072 if (!EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
))
3075 #ifdef EXTENTS_STATS
3076 if (EXT4_SB(sb
)->s_ext_blocks
&& EXT4_SB(sb
)->s_ext_extents
) {
3077 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
3078 printk(KERN_ERR
"EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
3079 sbi
->s_ext_blocks
, sbi
->s_ext_extents
,
3080 sbi
->s_ext_blocks
/ sbi
->s_ext_extents
);
3081 printk(KERN_ERR
"EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
3082 sbi
->s_ext_min
, sbi
->s_ext_max
, sbi
->s_depth_max
);
3087 static int ext4_zeroout_es(struct inode
*inode
, struct ext4_extent
*ex
)
3089 ext4_lblk_t ee_block
;
3090 ext4_fsblk_t ee_pblock
;
3091 unsigned int ee_len
;
3093 ee_block
= le32_to_cpu(ex
->ee_block
);
3094 ee_len
= ext4_ext_get_actual_len(ex
);
3095 ee_pblock
= ext4_ext_pblock(ex
);
3100 return ext4_es_insert_extent(inode
, ee_block
, ee_len
, ee_pblock
,
3101 EXTENT_STATUS_WRITTEN
);
3104 /* FIXME!! we need to try to merge to left or right after zero-out */
3105 static int ext4_ext_zeroout(struct inode
*inode
, struct ext4_extent
*ex
)
3107 ext4_fsblk_t ee_pblock
;
3108 unsigned int ee_len
;
3111 ee_len
= ext4_ext_get_actual_len(ex
);
3112 ee_pblock
= ext4_ext_pblock(ex
);
3114 ret
= sb_issue_zeroout(inode
->i_sb
, ee_pblock
, ee_len
, GFP_NOFS
);
3122 * ext4_split_extent_at() splits an extent at given block.
3124 * @handle: the journal handle
3125 * @inode: the file inode
3126 * @path: the path to the extent
3127 * @split: the logical block where the extent is splitted.
3128 * @split_flags: indicates if the extent could be zeroout if split fails, and
3129 * the states(init or unwritten) of new extents.
3130 * @flags: flags used to insert new extent to extent tree.
3133 * Splits extent [a, b] into two extents [a, @split) and [@split, b], states
3134 * of which are deterimined by split_flag.
3136 * There are two cases:
3137 * a> the extent are splitted into two extent.
3138 * b> split is not needed, and just mark the extent.
3140 * return 0 on success.
3142 static int ext4_split_extent_at(handle_t
*handle
,
3143 struct inode
*inode
,
3144 struct ext4_ext_path
**ppath
,
3149 struct ext4_ext_path
*path
= *ppath
;
3150 ext4_fsblk_t newblock
;
3151 ext4_lblk_t ee_block
;
3152 struct ext4_extent
*ex
, newex
, orig_ex
, zero_ex
;
3153 struct ext4_extent
*ex2
= NULL
;
3154 unsigned int ee_len
, depth
;
3157 BUG_ON((split_flag
& (EXT4_EXT_DATA_VALID1
| EXT4_EXT_DATA_VALID2
)) ==
3158 (EXT4_EXT_DATA_VALID1
| EXT4_EXT_DATA_VALID2
));
3160 ext_debug("ext4_split_extents_at: inode %lu, logical"
3161 "block %llu\n", inode
->i_ino
, (unsigned long long)split
);
3163 ext4_ext_show_leaf(inode
, path
);
3165 depth
= ext_depth(inode
);
3166 ex
= path
[depth
].p_ext
;
3167 ee_block
= le32_to_cpu(ex
->ee_block
);
3168 ee_len
= ext4_ext_get_actual_len(ex
);
3169 newblock
= split
- ee_block
+ ext4_ext_pblock(ex
);
3171 BUG_ON(split
< ee_block
|| split
>= (ee_block
+ ee_len
));
3172 BUG_ON(!ext4_ext_is_unwritten(ex
) &&
3173 split_flag
& (EXT4_EXT_MAY_ZEROOUT
|
3174 EXT4_EXT_MARK_UNWRIT1
|
3175 EXT4_EXT_MARK_UNWRIT2
));
3177 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3181 if (split
== ee_block
) {
3183 * case b: block @split is the block that the extent begins with
3184 * then we just change the state of the extent, and splitting
3187 if (split_flag
& EXT4_EXT_MARK_UNWRIT2
)
3188 ext4_ext_mark_unwritten(ex
);
3190 ext4_ext_mark_initialized(ex
);
3192 if (!(flags
& EXT4_GET_BLOCKS_PRE_IO
))
3193 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3195 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3200 memcpy(&orig_ex
, ex
, sizeof(orig_ex
));
3201 ex
->ee_len
= cpu_to_le16(split
- ee_block
);
3202 if (split_flag
& EXT4_EXT_MARK_UNWRIT1
)
3203 ext4_ext_mark_unwritten(ex
);
3206 * path may lead to new leaf, not to original leaf any more
3207 * after ext4_ext_insert_extent() returns,
3209 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
3211 goto fix_extent_len
;
3214 ex2
->ee_block
= cpu_to_le32(split
);
3215 ex2
->ee_len
= cpu_to_le16(ee_len
- (split
- ee_block
));
3216 ext4_ext_store_pblock(ex2
, newblock
);
3217 if (split_flag
& EXT4_EXT_MARK_UNWRIT2
)
3218 ext4_ext_mark_unwritten(ex2
);
3220 err
= ext4_ext_insert_extent(handle
, inode
, ppath
, &newex
, flags
);
3221 if (err
== -ENOSPC
&& (EXT4_EXT_MAY_ZEROOUT
& split_flag
)) {
3222 if (split_flag
& (EXT4_EXT_DATA_VALID1
|EXT4_EXT_DATA_VALID2
)) {
3223 if (split_flag
& EXT4_EXT_DATA_VALID1
) {
3224 err
= ext4_ext_zeroout(inode
, ex2
);
3225 zero_ex
.ee_block
= ex2
->ee_block
;
3226 zero_ex
.ee_len
= cpu_to_le16(
3227 ext4_ext_get_actual_len(ex2
));
3228 ext4_ext_store_pblock(&zero_ex
,
3229 ext4_ext_pblock(ex2
));
3231 err
= ext4_ext_zeroout(inode
, ex
);
3232 zero_ex
.ee_block
= ex
->ee_block
;
3233 zero_ex
.ee_len
= cpu_to_le16(
3234 ext4_ext_get_actual_len(ex
));
3235 ext4_ext_store_pblock(&zero_ex
,
3236 ext4_ext_pblock(ex
));
3239 err
= ext4_ext_zeroout(inode
, &orig_ex
);
3240 zero_ex
.ee_block
= orig_ex
.ee_block
;
3241 zero_ex
.ee_len
= cpu_to_le16(
3242 ext4_ext_get_actual_len(&orig_ex
));
3243 ext4_ext_store_pblock(&zero_ex
,
3244 ext4_ext_pblock(&orig_ex
));
3248 goto fix_extent_len
;
3249 /* update the extent length and mark as initialized */
3250 ex
->ee_len
= cpu_to_le16(ee_len
);
3251 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3252 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3254 goto fix_extent_len
;
3256 /* update extent status tree */
3257 err
= ext4_zeroout_es(inode
, &zero_ex
);
3261 goto fix_extent_len
;
3264 ext4_ext_show_leaf(inode
, path
);
3268 ex
->ee_len
= orig_ex
.ee_len
;
3269 ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3274 * ext4_split_extents() splits an extent and mark extent which is covered
3275 * by @map as split_flags indicates
3277 * It may result in splitting the extent into multiple extents (up to three)
3278 * There are three possibilities:
3279 * a> There is no split required
3280 * b> Splits in two extents: Split is happening at either end of the extent
3281 * c> Splits in three extents: Somone is splitting in middle of the extent
3284 static int ext4_split_extent(handle_t
*handle
,
3285 struct inode
*inode
,
3286 struct ext4_ext_path
**ppath
,
3287 struct ext4_map_blocks
*map
,
3291 struct ext4_ext_path
*path
= *ppath
;
3292 ext4_lblk_t ee_block
;
3293 struct ext4_extent
*ex
;
3294 unsigned int ee_len
, depth
;
3297 int split_flag1
, flags1
;
3298 int allocated
= map
->m_len
;
3300 depth
= ext_depth(inode
);
3301 ex
= path
[depth
].p_ext
;
3302 ee_block
= le32_to_cpu(ex
->ee_block
);
3303 ee_len
= ext4_ext_get_actual_len(ex
);
3304 unwritten
= ext4_ext_is_unwritten(ex
);
3306 if (map
->m_lblk
+ map
->m_len
< ee_block
+ ee_len
) {
3307 split_flag1
= split_flag
& EXT4_EXT_MAY_ZEROOUT
;
3308 flags1
= flags
| EXT4_GET_BLOCKS_PRE_IO
;
3310 split_flag1
|= EXT4_EXT_MARK_UNWRIT1
|
3311 EXT4_EXT_MARK_UNWRIT2
;
3312 if (split_flag
& EXT4_EXT_DATA_VALID2
)
3313 split_flag1
|= EXT4_EXT_DATA_VALID1
;
3314 err
= ext4_split_extent_at(handle
, inode
, ppath
,
3315 map
->m_lblk
+ map
->m_len
, split_flag1
, flags1
);
3319 allocated
= ee_len
- (map
->m_lblk
- ee_block
);
3322 * Update path is required because previous ext4_split_extent_at() may
3323 * result in split of original leaf or extent zeroout.
3325 path
= ext4_find_extent(inode
, map
->m_lblk
, ppath
, 0);
3327 return PTR_ERR(path
);
3328 depth
= ext_depth(inode
);
3329 ex
= path
[depth
].p_ext
;
3331 EXT4_ERROR_INODE(inode
, "unexpected hole at %lu",
3332 (unsigned long) map
->m_lblk
);
3335 unwritten
= ext4_ext_is_unwritten(ex
);
3338 if (map
->m_lblk
>= ee_block
) {
3339 split_flag1
= split_flag
& EXT4_EXT_DATA_VALID2
;
3341 split_flag1
|= EXT4_EXT_MARK_UNWRIT1
;
3342 split_flag1
|= split_flag
& (EXT4_EXT_MAY_ZEROOUT
|
3343 EXT4_EXT_MARK_UNWRIT2
);
3345 err
= ext4_split_extent_at(handle
, inode
, ppath
,
3346 map
->m_lblk
, split_flag1
, flags
);
3351 ext4_ext_show_leaf(inode
, path
);
3353 return err
? err
: allocated
;
3357 * This function is called by ext4_ext_map_blocks() if someone tries to write
3358 * to an unwritten extent. It may result in splitting the unwritten
3359 * extent into multiple extents (up to three - one initialized and two
3361 * There are three possibilities:
3362 * a> There is no split required: Entire extent should be initialized
3363 * b> Splits in two extents: Write is happening at either end of the extent
3364 * c> Splits in three extents: Somone is writing in middle of the extent
3367 * - The extent pointed to by 'path' is unwritten.
3368 * - The extent pointed to by 'path' contains a superset
3369 * of the logical span [map->m_lblk, map->m_lblk + map->m_len).
3371 * Post-conditions on success:
3372 * - the returned value is the number of blocks beyond map->l_lblk
3373 * that are allocated and initialized.
3374 * It is guaranteed to be >= map->m_len.
3376 static int ext4_ext_convert_to_initialized(handle_t
*handle
,
3377 struct inode
*inode
,
3378 struct ext4_map_blocks
*map
,
3379 struct ext4_ext_path
**ppath
,
3382 struct ext4_ext_path
*path
= *ppath
;
3383 struct ext4_sb_info
*sbi
;
3384 struct ext4_extent_header
*eh
;
3385 struct ext4_map_blocks split_map
;
3386 struct ext4_extent zero_ex
;
3387 struct ext4_extent
*ex
, *abut_ex
;
3388 ext4_lblk_t ee_block
, eof_block
;
3389 unsigned int ee_len
, depth
, map_len
= map
->m_len
;
3390 int allocated
= 0, max_zeroout
= 0;
3394 ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
3395 "block %llu, max_blocks %u\n", inode
->i_ino
,
3396 (unsigned long long)map
->m_lblk
, map_len
);
3398 sbi
= EXT4_SB(inode
->i_sb
);
3399 eof_block
= (inode
->i_size
+ inode
->i_sb
->s_blocksize
- 1) >>
3400 inode
->i_sb
->s_blocksize_bits
;
3401 if (eof_block
< map
->m_lblk
+ map_len
)
3402 eof_block
= map
->m_lblk
+ map_len
;
3404 depth
= ext_depth(inode
);
3405 eh
= path
[depth
].p_hdr
;
3406 ex
= path
[depth
].p_ext
;
3407 ee_block
= le32_to_cpu(ex
->ee_block
);
3408 ee_len
= ext4_ext_get_actual_len(ex
);
3411 trace_ext4_ext_convert_to_initialized_enter(inode
, map
, ex
);
3413 /* Pre-conditions */
3414 BUG_ON(!ext4_ext_is_unwritten(ex
));
3415 BUG_ON(!in_range(map
->m_lblk
, ee_block
, ee_len
));
3418 * Attempt to transfer newly initialized blocks from the currently
3419 * unwritten extent to its neighbor. This is much cheaper
3420 * than an insertion followed by a merge as those involve costly
3421 * memmove() calls. Transferring to the left is the common case in
3422 * steady state for workloads doing fallocate(FALLOC_FL_KEEP_SIZE)
3423 * followed by append writes.
3425 * Limitations of the current logic:
3426 * - L1: we do not deal with writes covering the whole extent.
3427 * This would require removing the extent if the transfer
3429 * - L2: we only attempt to merge with an extent stored in the
3430 * same extent tree node.
3432 if ((map
->m_lblk
== ee_block
) &&
3433 /* See if we can merge left */
3434 (map_len
< ee_len
) && /*L1*/
3435 (ex
> EXT_FIRST_EXTENT(eh
))) { /*L2*/
3436 ext4_lblk_t prev_lblk
;
3437 ext4_fsblk_t prev_pblk
, ee_pblk
;
3438 unsigned int prev_len
;
3441 prev_lblk
= le32_to_cpu(abut_ex
->ee_block
);
3442 prev_len
= ext4_ext_get_actual_len(abut_ex
);
3443 prev_pblk
= ext4_ext_pblock(abut_ex
);
3444 ee_pblk
= ext4_ext_pblock(ex
);
3447 * A transfer of blocks from 'ex' to 'abut_ex' is allowed
3448 * upon those conditions:
3449 * - C1: abut_ex is initialized,
3450 * - C2: abut_ex is logically abutting ex,
3451 * - C3: abut_ex is physically abutting ex,
3452 * - C4: abut_ex can receive the additional blocks without
3453 * overflowing the (initialized) length limit.
3455 if ((!ext4_ext_is_unwritten(abut_ex
)) && /*C1*/
3456 ((prev_lblk
+ prev_len
) == ee_block
) && /*C2*/
3457 ((prev_pblk
+ prev_len
) == ee_pblk
) && /*C3*/
3458 (prev_len
< (EXT_INIT_MAX_LEN
- map_len
))) { /*C4*/
3459 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3463 trace_ext4_ext_convert_to_initialized_fastpath(inode
,
3466 /* Shift the start of ex by 'map_len' blocks */
3467 ex
->ee_block
= cpu_to_le32(ee_block
+ map_len
);
3468 ext4_ext_store_pblock(ex
, ee_pblk
+ map_len
);
3469 ex
->ee_len
= cpu_to_le16(ee_len
- map_len
);
3470 ext4_ext_mark_unwritten(ex
); /* Restore the flag */
3472 /* Extend abut_ex by 'map_len' blocks */
3473 abut_ex
->ee_len
= cpu_to_le16(prev_len
+ map_len
);
3475 /* Result: number of initialized blocks past m_lblk */
3476 allocated
= map_len
;
3478 } else if (((map
->m_lblk
+ map_len
) == (ee_block
+ ee_len
)) &&
3479 (map_len
< ee_len
) && /*L1*/
3480 ex
< EXT_LAST_EXTENT(eh
)) { /*L2*/
3481 /* See if we can merge right */
3482 ext4_lblk_t next_lblk
;
3483 ext4_fsblk_t next_pblk
, ee_pblk
;
3484 unsigned int next_len
;
3487 next_lblk
= le32_to_cpu(abut_ex
->ee_block
);
3488 next_len
= ext4_ext_get_actual_len(abut_ex
);
3489 next_pblk
= ext4_ext_pblock(abut_ex
);
3490 ee_pblk
= ext4_ext_pblock(ex
);
3493 * A transfer of blocks from 'ex' to 'abut_ex' is allowed
3494 * upon those conditions:
3495 * - C1: abut_ex is initialized,
3496 * - C2: abut_ex is logically abutting ex,
3497 * - C3: abut_ex is physically abutting ex,
3498 * - C4: abut_ex can receive the additional blocks without
3499 * overflowing the (initialized) length limit.
3501 if ((!ext4_ext_is_unwritten(abut_ex
)) && /*C1*/
3502 ((map
->m_lblk
+ map_len
) == next_lblk
) && /*C2*/
3503 ((ee_pblk
+ ee_len
) == next_pblk
) && /*C3*/
3504 (next_len
< (EXT_INIT_MAX_LEN
- map_len
))) { /*C4*/
3505 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3509 trace_ext4_ext_convert_to_initialized_fastpath(inode
,
3512 /* Shift the start of abut_ex by 'map_len' blocks */
3513 abut_ex
->ee_block
= cpu_to_le32(next_lblk
- map_len
);
3514 ext4_ext_store_pblock(abut_ex
, next_pblk
- map_len
);
3515 ex
->ee_len
= cpu_to_le16(ee_len
- map_len
);
3516 ext4_ext_mark_unwritten(ex
); /* Restore the flag */
3518 /* Extend abut_ex by 'map_len' blocks */
3519 abut_ex
->ee_len
= cpu_to_le16(next_len
+ map_len
);
3521 /* Result: number of initialized blocks past m_lblk */
3522 allocated
= map_len
;
3526 /* Mark the block containing both extents as dirty */
3527 ext4_ext_dirty(handle
, inode
, path
+ depth
);
3529 /* Update path to point to the right extent */
3530 path
[depth
].p_ext
= abut_ex
;
3533 allocated
= ee_len
- (map
->m_lblk
- ee_block
);
3535 WARN_ON(map
->m_lblk
< ee_block
);
3537 * It is safe to convert extent to initialized via explicit
3538 * zeroout only if extent is fully inside i_size or new_size.
3540 split_flag
|= ee_block
+ ee_len
<= eof_block
? EXT4_EXT_MAY_ZEROOUT
: 0;
3542 if (EXT4_EXT_MAY_ZEROOUT
& split_flag
)
3543 max_zeroout
= sbi
->s_extent_max_zeroout_kb
>>
3544 (inode
->i_sb
->s_blocksize_bits
- 10);
3546 /* If extent is less than s_max_zeroout_kb, zeroout directly */
3547 if (max_zeroout
&& (ee_len
<= max_zeroout
)) {
3548 err
= ext4_ext_zeroout(inode
, ex
);
3551 zero_ex
.ee_block
= ex
->ee_block
;
3552 zero_ex
.ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
));
3553 ext4_ext_store_pblock(&zero_ex
, ext4_ext_pblock(ex
));
3555 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3558 ext4_ext_mark_initialized(ex
);
3559 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3560 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3566 * 1. split the extent into three extents.
3567 * 2. split the extent into two extents, zeroout the first half.
3568 * 3. split the extent into two extents, zeroout the second half.
3569 * 4. split the extent into two extents with out zeroout.
3571 split_map
.m_lblk
= map
->m_lblk
;
3572 split_map
.m_len
= map
->m_len
;
3574 if (max_zeroout
&& (allocated
> map
->m_len
)) {
3575 if (allocated
<= max_zeroout
) {
3578 cpu_to_le32(map
->m_lblk
);
3579 zero_ex
.ee_len
= cpu_to_le16(allocated
);
3580 ext4_ext_store_pblock(&zero_ex
,
3581 ext4_ext_pblock(ex
) + map
->m_lblk
- ee_block
);
3582 err
= ext4_ext_zeroout(inode
, &zero_ex
);
3585 split_map
.m_lblk
= map
->m_lblk
;
3586 split_map
.m_len
= allocated
;
3587 } else if (map
->m_lblk
- ee_block
+ map
->m_len
< max_zeroout
) {
3589 if (map
->m_lblk
!= ee_block
) {
3590 zero_ex
.ee_block
= ex
->ee_block
;
3591 zero_ex
.ee_len
= cpu_to_le16(map
->m_lblk
-
3593 ext4_ext_store_pblock(&zero_ex
,
3594 ext4_ext_pblock(ex
));
3595 err
= ext4_ext_zeroout(inode
, &zero_ex
);
3600 split_map
.m_lblk
= ee_block
;
3601 split_map
.m_len
= map
->m_lblk
- ee_block
+ map
->m_len
;
3602 allocated
= map
->m_len
;
3606 allocated
= ext4_split_extent(handle
, inode
, ppath
,
3607 &split_map
, split_flag
, flags
);
3612 /* If we have gotten a failure, don't zero out status tree */
3614 err
= ext4_zeroout_es(inode
, &zero_ex
);
3615 return err
? err
: allocated
;
3619 * This function is called by ext4_ext_map_blocks() from
3620 * ext4_get_blocks_dio_write() when DIO to write
3621 * to an unwritten extent.
3623 * Writing to an unwritten extent may result in splitting the unwritten
3624 * extent into multiple initialized/unwritten extents (up to three)
3625 * There are three possibilities:
3626 * a> There is no split required: Entire extent should be unwritten
3627 * b> Splits in two extents: Write is happening at either end of the extent
3628 * c> Splits in three extents: Somone is writing in middle of the extent
3630 * This works the same way in the case of initialized -> unwritten conversion.
3632 * One of more index blocks maybe needed if the extent tree grow after
3633 * the unwritten extent split. To prevent ENOSPC occur at the IO
3634 * complete, we need to split the unwritten extent before DIO submit
3635 * the IO. The unwritten extent called at this time will be split
3636 * into three unwritten extent(at most). After IO complete, the part
3637 * being filled will be convert to initialized by the end_io callback function
3638 * via ext4_convert_unwritten_extents().
3640 * Returns the size of unwritten extent to be written on success.
3642 static int ext4_split_convert_extents(handle_t
*handle
,
3643 struct inode
*inode
,
3644 struct ext4_map_blocks
*map
,
3645 struct ext4_ext_path
**ppath
,
3648 struct ext4_ext_path
*path
= *ppath
;
3649 ext4_lblk_t eof_block
;
3650 ext4_lblk_t ee_block
;
3651 struct ext4_extent
*ex
;
3652 unsigned int ee_len
;
3653 int split_flag
= 0, depth
;
3655 ext_debug("%s: inode %lu, logical block %llu, max_blocks %u\n",
3656 __func__
, inode
->i_ino
,
3657 (unsigned long long)map
->m_lblk
, map
->m_len
);
3659 eof_block
= (inode
->i_size
+ inode
->i_sb
->s_blocksize
- 1) >>
3660 inode
->i_sb
->s_blocksize_bits
;
3661 if (eof_block
< map
->m_lblk
+ map
->m_len
)
3662 eof_block
= map
->m_lblk
+ map
->m_len
;
3664 * It is safe to convert extent to initialized via explicit
3665 * zeroout only if extent is fully insde i_size or new_size.
3667 depth
= ext_depth(inode
);
3668 ex
= path
[depth
].p_ext
;
3669 ee_block
= le32_to_cpu(ex
->ee_block
);
3670 ee_len
= ext4_ext_get_actual_len(ex
);
3672 /* Convert to unwritten */
3673 if (flags
& EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
) {
3674 split_flag
|= EXT4_EXT_DATA_VALID1
;
3675 /* Convert to initialized */
3676 } else if (flags
& EXT4_GET_BLOCKS_CONVERT
) {
3677 split_flag
|= ee_block
+ ee_len
<= eof_block
?
3678 EXT4_EXT_MAY_ZEROOUT
: 0;
3679 split_flag
|= (EXT4_EXT_MARK_UNWRIT2
| EXT4_EXT_DATA_VALID2
);
3681 flags
|= EXT4_GET_BLOCKS_PRE_IO
;
3682 return ext4_split_extent(handle
, inode
, ppath
, map
, split_flag
, flags
);
3685 static int ext4_convert_unwritten_extents_endio(handle_t
*handle
,
3686 struct inode
*inode
,
3687 struct ext4_map_blocks
*map
,
3688 struct ext4_ext_path
**ppath
)
3690 struct ext4_ext_path
*path
= *ppath
;
3691 struct ext4_extent
*ex
;
3692 ext4_lblk_t ee_block
;
3693 unsigned int ee_len
;
3697 depth
= ext_depth(inode
);
3698 ex
= path
[depth
].p_ext
;
3699 ee_block
= le32_to_cpu(ex
->ee_block
);
3700 ee_len
= ext4_ext_get_actual_len(ex
);
3702 ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical"
3703 "block %llu, max_blocks %u\n", inode
->i_ino
,
3704 (unsigned long long)ee_block
, ee_len
);
3706 /* If extent is larger than requested it is a clear sign that we still
3707 * have some extent state machine issues left. So extent_split is still
3709 * TODO: Once all related issues will be fixed this situation should be
3712 if (ee_block
!= map
->m_lblk
|| ee_len
> map
->m_len
) {
3714 ext4_warning("Inode (%ld) finished: extent logical block %llu,"
3715 " len %u; IO logical block %llu, len %u\n",
3716 inode
->i_ino
, (unsigned long long)ee_block
, ee_len
,
3717 (unsigned long long)map
->m_lblk
, map
->m_len
);
3719 err
= ext4_split_convert_extents(handle
, inode
, map
, ppath
,
3720 EXT4_GET_BLOCKS_CONVERT
);
3723 path
= ext4_find_extent(inode
, map
->m_lblk
, ppath
, 0);
3725 return PTR_ERR(path
);
3726 depth
= ext_depth(inode
);
3727 ex
= path
[depth
].p_ext
;
3730 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3733 /* first mark the extent as initialized */
3734 ext4_ext_mark_initialized(ex
);
3736 /* note: ext4_ext_correct_indexes() isn't needed here because
3737 * borders are not changed
3739 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3741 /* Mark modified extent as dirty */
3742 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3744 ext4_ext_show_leaf(inode
, path
);
3748 static void unmap_underlying_metadata_blocks(struct block_device
*bdev
,
3749 sector_t block
, int count
)
3752 for (i
= 0; i
< count
; i
++)
3753 unmap_underlying_metadata(bdev
, block
+ i
);
3757 * Handle EOFBLOCKS_FL flag, clearing it if necessary
3759 static int check_eofblocks_fl(handle_t
*handle
, struct inode
*inode
,
3761 struct ext4_ext_path
*path
,
3765 struct ext4_extent_header
*eh
;
3766 struct ext4_extent
*last_ex
;
3768 if (!ext4_test_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
))
3771 depth
= ext_depth(inode
);
3772 eh
= path
[depth
].p_hdr
;
3775 * We're going to remove EOFBLOCKS_FL entirely in future so we
3776 * do not care for this case anymore. Simply remove the flag
3777 * if there are no extents.
3779 if (unlikely(!eh
->eh_entries
))
3781 last_ex
= EXT_LAST_EXTENT(eh
);
3783 * We should clear the EOFBLOCKS_FL flag if we are writing the
3784 * last block in the last extent in the file. We test this by
3785 * first checking to see if the caller to
3786 * ext4_ext_get_blocks() was interested in the last block (or
3787 * a block beyond the last block) in the current extent. If
3788 * this turns out to be false, we can bail out from this
3789 * function immediately.
3791 if (lblk
+ len
< le32_to_cpu(last_ex
->ee_block
) +
3792 ext4_ext_get_actual_len(last_ex
))
3795 * If the caller does appear to be planning to write at or
3796 * beyond the end of the current extent, we then test to see
3797 * if the current extent is the last extent in the file, by
3798 * checking to make sure it was reached via the rightmost node
3799 * at each level of the tree.
3801 for (i
= depth
-1; i
>= 0; i
--)
3802 if (path
[i
].p_idx
!= EXT_LAST_INDEX(path
[i
].p_hdr
))
3805 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3806 return ext4_mark_inode_dirty(handle
, inode
);
3810 * ext4_find_delalloc_range: find delayed allocated block in the given range.
3812 * Return 1 if there is a delalloc block in the range, otherwise 0.
3814 int ext4_find_delalloc_range(struct inode
*inode
,
3815 ext4_lblk_t lblk_start
,
3816 ext4_lblk_t lblk_end
)
3818 struct extent_status es
;
3820 ext4_es_find_delayed_extent_range(inode
, lblk_start
, lblk_end
, &es
);
3822 return 0; /* there is no delay extent in this tree */
3823 else if (es
.es_lblk
<= lblk_start
&&
3824 lblk_start
< es
.es_lblk
+ es
.es_len
)
3826 else if (lblk_start
<= es
.es_lblk
&& es
.es_lblk
<= lblk_end
)
3832 int ext4_find_delalloc_cluster(struct inode
*inode
, ext4_lblk_t lblk
)
3834 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
3835 ext4_lblk_t lblk_start
, lblk_end
;
3836 lblk_start
= EXT4_LBLK_CMASK(sbi
, lblk
);
3837 lblk_end
= lblk_start
+ sbi
->s_cluster_ratio
- 1;
3839 return ext4_find_delalloc_range(inode
, lblk_start
, lblk_end
);
3843 * Determines how many complete clusters (out of those specified by the 'map')
3844 * are under delalloc and were reserved quota for.
3845 * This function is called when we are writing out the blocks that were
3846 * originally written with their allocation delayed, but then the space was
3847 * allocated using fallocate() before the delayed allocation could be resolved.
3848 * The cases to look for are:
3849 * ('=' indicated delayed allocated blocks
3850 * '-' indicates non-delayed allocated blocks)
3851 * (a) partial clusters towards beginning and/or end outside of allocated range
3852 * are not delalloc'ed.
3854 * |----c---=|====c====|====c====|===-c----|
3855 * |++++++ allocated ++++++|
3856 * ==> 4 complete clusters in above example
3858 * (b) partial cluster (outside of allocated range) towards either end is
3859 * marked for delayed allocation. In this case, we will exclude that
3862 * |----====c========|========c========|
3863 * |++++++ allocated ++++++|
3864 * ==> 1 complete clusters in above example
3867 * |================c================|
3868 * |++++++ allocated ++++++|
3869 * ==> 0 complete clusters in above example
3871 * The ext4_da_update_reserve_space will be called only if we
3872 * determine here that there were some "entire" clusters that span
3873 * this 'allocated' range.
3874 * In the non-bigalloc case, this function will just end up returning num_blks
3875 * without ever calling ext4_find_delalloc_range.
3878 get_reserved_cluster_alloc(struct inode
*inode
, ext4_lblk_t lblk_start
,
3879 unsigned int num_blks
)
3881 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
3882 ext4_lblk_t alloc_cluster_start
, alloc_cluster_end
;
3883 ext4_lblk_t lblk_from
, lblk_to
, c_offset
;
3884 unsigned int allocated_clusters
= 0;
3886 alloc_cluster_start
= EXT4_B2C(sbi
, lblk_start
);
3887 alloc_cluster_end
= EXT4_B2C(sbi
, lblk_start
+ num_blks
- 1);
3889 /* max possible clusters for this allocation */
3890 allocated_clusters
= alloc_cluster_end
- alloc_cluster_start
+ 1;
3892 trace_ext4_get_reserved_cluster_alloc(inode
, lblk_start
, num_blks
);
3894 /* Check towards left side */
3895 c_offset
= EXT4_LBLK_COFF(sbi
, lblk_start
);
3897 lblk_from
= EXT4_LBLK_CMASK(sbi
, lblk_start
);
3898 lblk_to
= lblk_from
+ c_offset
- 1;
3900 if (ext4_find_delalloc_range(inode
, lblk_from
, lblk_to
))
3901 allocated_clusters
--;
3904 /* Now check towards right. */
3905 c_offset
= EXT4_LBLK_COFF(sbi
, lblk_start
+ num_blks
);
3906 if (allocated_clusters
&& c_offset
) {
3907 lblk_from
= lblk_start
+ num_blks
;
3908 lblk_to
= lblk_from
+ (sbi
->s_cluster_ratio
- c_offset
) - 1;
3910 if (ext4_find_delalloc_range(inode
, lblk_from
, lblk_to
))
3911 allocated_clusters
--;
3914 return allocated_clusters
;
3918 convert_initialized_extent(handle_t
*handle
, struct inode
*inode
,
3919 struct ext4_map_blocks
*map
,
3920 struct ext4_ext_path
**ppath
, int flags
,
3921 unsigned int allocated
, ext4_fsblk_t newblock
)
3923 struct ext4_ext_path
*path
= *ppath
;
3924 struct ext4_extent
*ex
;
3925 ext4_lblk_t ee_block
;
3926 unsigned int ee_len
;
3931 * Make sure that the extent is no bigger than we support with
3934 if (map
->m_len
> EXT_UNWRITTEN_MAX_LEN
)
3935 map
->m_len
= EXT_UNWRITTEN_MAX_LEN
/ 2;
3937 depth
= ext_depth(inode
);
3938 ex
= path
[depth
].p_ext
;
3939 ee_block
= le32_to_cpu(ex
->ee_block
);
3940 ee_len
= ext4_ext_get_actual_len(ex
);
3942 ext_debug("%s: inode %lu, logical"
3943 "block %llu, max_blocks %u\n", __func__
, inode
->i_ino
,
3944 (unsigned long long)ee_block
, ee_len
);
3946 if (ee_block
!= map
->m_lblk
|| ee_len
> map
->m_len
) {
3947 err
= ext4_split_convert_extents(handle
, inode
, map
, ppath
,
3948 EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
);
3951 path
= ext4_find_extent(inode
, map
->m_lblk
, ppath
, 0);
3953 return PTR_ERR(path
);
3954 depth
= ext_depth(inode
);
3955 ex
= path
[depth
].p_ext
;
3957 EXT4_ERROR_INODE(inode
, "unexpected hole at %lu",
3958 (unsigned long) map
->m_lblk
);
3963 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3966 /* first mark the extent as unwritten */
3967 ext4_ext_mark_unwritten(ex
);
3969 /* note: ext4_ext_correct_indexes() isn't needed here because
3970 * borders are not changed
3972 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3974 /* Mark modified extent as dirty */
3975 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3978 ext4_ext_show_leaf(inode
, path
);
3980 ext4_update_inode_fsync_trans(handle
, inode
, 1);
3981 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
, path
, map
->m_len
);
3984 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
3985 if (allocated
> map
->m_len
)
3986 allocated
= map
->m_len
;
3987 map
->m_len
= allocated
;
3992 ext4_ext_handle_unwritten_extents(handle_t
*handle
, struct inode
*inode
,
3993 struct ext4_map_blocks
*map
,
3994 struct ext4_ext_path
**ppath
, int flags
,
3995 unsigned int allocated
, ext4_fsblk_t newblock
)
3997 struct ext4_ext_path
*path
= *ppath
;
4000 ext4_io_end_t
*io
= ext4_inode_aio(inode
);
4002 ext_debug("ext4_ext_handle_unwritten_extents: inode %lu, logical "
4003 "block %llu, max_blocks %u, flags %x, allocated %u\n",
4004 inode
->i_ino
, (unsigned long long)map
->m_lblk
, map
->m_len
,
4006 ext4_ext_show_leaf(inode
, path
);
4009 * When writing into unwritten space, we should not fail to
4010 * allocate metadata blocks for the new extent block if needed.
4012 flags
|= EXT4_GET_BLOCKS_METADATA_NOFAIL
;
4014 trace_ext4_ext_handle_unwritten_extents(inode
, map
, flags
,
4015 allocated
, newblock
);
4017 /* get_block() before submit the IO, split the extent */
4018 if (flags
& EXT4_GET_BLOCKS_PRE_IO
) {
4019 ret
= ext4_split_convert_extents(handle
, inode
, map
, ppath
,
4020 flags
| EXT4_GET_BLOCKS_CONVERT
);
4024 * Flag the inode(non aio case) or end_io struct (aio case)
4025 * that this IO needs to conversion to written when IO is
4029 ext4_set_io_unwritten_flag(inode
, io
);
4031 ext4_set_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
4032 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
4035 /* IO end_io complete, convert the filled extent to written */
4036 if (flags
& EXT4_GET_BLOCKS_CONVERT
) {
4037 ret
= ext4_convert_unwritten_extents_endio(handle
, inode
, map
,
4040 ext4_update_inode_fsync_trans(handle
, inode
, 1);
4041 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
,
4045 map
->m_flags
|= EXT4_MAP_MAPPED
;
4046 map
->m_pblk
= newblock
;
4047 if (allocated
> map
->m_len
)
4048 allocated
= map
->m_len
;
4049 map
->m_len
= allocated
;
4052 /* buffered IO case */
4054 * repeat fallocate creation request
4055 * we already have an unwritten extent
4057 if (flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
) {
4058 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
4062 /* buffered READ or buffered write_begin() lookup */
4063 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
4065 * We have blocks reserved already. We
4066 * return allocated blocks so that delalloc
4067 * won't do block reservation for us. But
4068 * the buffer head will be unmapped so that
4069 * a read from the block returns 0s.
4071 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
4075 /* buffered write, writepage time, convert*/
4076 ret
= ext4_ext_convert_to_initialized(handle
, inode
, map
, ppath
, flags
);
4078 ext4_update_inode_fsync_trans(handle
, inode
, 1);
4085 map
->m_flags
|= EXT4_MAP_NEW
;
4087 * if we allocated more blocks than requested
4088 * we need to make sure we unmap the extra block
4089 * allocated. The actual needed block will get
4090 * unmapped later when we find the buffer_head marked
4093 if (allocated
> map
->m_len
) {
4094 unmap_underlying_metadata_blocks(inode
->i_sb
->s_bdev
,
4095 newblock
+ map
->m_len
,
4096 allocated
- map
->m_len
);
4097 allocated
= map
->m_len
;
4099 map
->m_len
= allocated
;
4102 * If we have done fallocate with the offset that is already
4103 * delayed allocated, we would have block reservation
4104 * and quota reservation done in the delayed write path.
4105 * But fallocate would have already updated quota and block
4106 * count for this offset. So cancel these reservation
4108 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) {
4109 unsigned int reserved_clusters
;
4110 reserved_clusters
= get_reserved_cluster_alloc(inode
,
4111 map
->m_lblk
, map
->m_len
);
4112 if (reserved_clusters
)
4113 ext4_da_update_reserve_space(inode
,
4119 map
->m_flags
|= EXT4_MAP_MAPPED
;
4120 if ((flags
& EXT4_GET_BLOCKS_KEEP_SIZE
) == 0) {
4121 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
, path
,
4127 if (allocated
> map
->m_len
)
4128 allocated
= map
->m_len
;
4129 ext4_ext_show_leaf(inode
, path
);
4130 map
->m_pblk
= newblock
;
4131 map
->m_len
= allocated
;
4133 return err
? err
: allocated
;
4137 * get_implied_cluster_alloc - check to see if the requested
4138 * allocation (in the map structure) overlaps with a cluster already
4139 * allocated in an extent.
4140 * @sb The filesystem superblock structure
4141 * @map The requested lblk->pblk mapping
4142 * @ex The extent structure which might contain an implied
4143 * cluster allocation
4145 * This function is called by ext4_ext_map_blocks() after we failed to
4146 * find blocks that were already in the inode's extent tree. Hence,
4147 * we know that the beginning of the requested region cannot overlap
4148 * the extent from the inode's extent tree. There are three cases we
4149 * want to catch. The first is this case:
4151 * |--- cluster # N--|
4152 * |--- extent ---| |---- requested region ---|
4155 * The second case that we need to test for is this one:
4157 * |--------- cluster # N ----------------|
4158 * |--- requested region --| |------- extent ----|
4159 * |=======================|
4161 * The third case is when the requested region lies between two extents
4162 * within the same cluster:
4163 * |------------- cluster # N-------------|
4164 * |----- ex -----| |---- ex_right ----|
4165 * |------ requested region ------|
4166 * |================|
4168 * In each of the above cases, we need to set the map->m_pblk and
4169 * map->m_len so it corresponds to the return the extent labelled as
4170 * "|====|" from cluster #N, since it is already in use for data in
4171 * cluster EXT4_B2C(sbi, map->m_lblk). We will then return 1 to
4172 * signal to ext4_ext_map_blocks() that map->m_pblk should be treated
4173 * as a new "allocated" block region. Otherwise, we will return 0 and
4174 * ext4_ext_map_blocks() will then allocate one or more new clusters
4175 * by calling ext4_mb_new_blocks().
4177 static int get_implied_cluster_alloc(struct super_block
*sb
,
4178 struct ext4_map_blocks
*map
,
4179 struct ext4_extent
*ex
,
4180 struct ext4_ext_path
*path
)
4182 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
4183 ext4_lblk_t c_offset
= EXT4_LBLK_COFF(sbi
, map
->m_lblk
);
4184 ext4_lblk_t ex_cluster_start
, ex_cluster_end
;
4185 ext4_lblk_t rr_cluster_start
;
4186 ext4_lblk_t ee_block
= le32_to_cpu(ex
->ee_block
);
4187 ext4_fsblk_t ee_start
= ext4_ext_pblock(ex
);
4188 unsigned short ee_len
= ext4_ext_get_actual_len(ex
);
4190 /* The extent passed in that we are trying to match */
4191 ex_cluster_start
= EXT4_B2C(sbi
, ee_block
);
4192 ex_cluster_end
= EXT4_B2C(sbi
, ee_block
+ ee_len
- 1);
4194 /* The requested region passed into ext4_map_blocks() */
4195 rr_cluster_start
= EXT4_B2C(sbi
, map
->m_lblk
);
4197 if ((rr_cluster_start
== ex_cluster_end
) ||
4198 (rr_cluster_start
== ex_cluster_start
)) {
4199 if (rr_cluster_start
== ex_cluster_end
)
4200 ee_start
+= ee_len
- 1;
4201 map
->m_pblk
= EXT4_PBLK_CMASK(sbi
, ee_start
) + c_offset
;
4202 map
->m_len
= min(map
->m_len
,
4203 (unsigned) sbi
->s_cluster_ratio
- c_offset
);
4205 * Check for and handle this case:
4207 * |--------- cluster # N-------------|
4208 * |------- extent ----|
4209 * |--- requested region ---|
4213 if (map
->m_lblk
< ee_block
)
4214 map
->m_len
= min(map
->m_len
, ee_block
- map
->m_lblk
);
4217 * Check for the case where there is already another allocated
4218 * block to the right of 'ex' but before the end of the cluster.
4220 * |------------- cluster # N-------------|
4221 * |----- ex -----| |---- ex_right ----|
4222 * |------ requested region ------|
4223 * |================|
4225 if (map
->m_lblk
> ee_block
) {
4226 ext4_lblk_t next
= ext4_ext_next_allocated_block(path
);
4227 map
->m_len
= min(map
->m_len
, next
- map
->m_lblk
);
4230 trace_ext4_get_implied_cluster_alloc_exit(sb
, map
, 1);
4234 trace_ext4_get_implied_cluster_alloc_exit(sb
, map
, 0);
4240 * Block allocation/map/preallocation routine for extents based files
4243 * Need to be called with
4244 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
4245 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
4247 * return > 0, number of of blocks already mapped/allocated
4248 * if create == 0 and these are pre-allocated blocks
4249 * buffer head is unmapped
4250 * otherwise blocks are mapped
4252 * return = 0, if plain look up failed (blocks have not been allocated)
4253 * buffer head is unmapped
4255 * return < 0, error case.
4257 int ext4_ext_map_blocks(handle_t
*handle
, struct inode
*inode
,
4258 struct ext4_map_blocks
*map
, int flags
)
4260 struct ext4_ext_path
*path
= NULL
;
4261 struct ext4_extent newex
, *ex
, *ex2
;
4262 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4263 ext4_fsblk_t newblock
= 0;
4264 int free_on_err
= 0, err
= 0, depth
, ret
;
4265 unsigned int allocated
= 0, offset
= 0;
4266 unsigned int allocated_clusters
= 0;
4267 struct ext4_allocation_request ar
;
4268 ext4_io_end_t
*io
= ext4_inode_aio(inode
);
4269 ext4_lblk_t cluster_offset
;
4270 int set_unwritten
= 0;
4272 ext_debug("blocks %u/%u requested for inode %lu\n",
4273 map
->m_lblk
, map
->m_len
, inode
->i_ino
);
4274 trace_ext4_ext_map_blocks_enter(inode
, map
->m_lblk
, map
->m_len
, flags
);
4276 /* find extent for this block */
4277 path
= ext4_find_extent(inode
, map
->m_lblk
, NULL
, 0);
4279 err
= PTR_ERR(path
);
4284 depth
= ext_depth(inode
);
4287 * consistent leaf must not be empty;
4288 * this situation is possible, though, _during_ tree modification;
4289 * this is why assert can't be put in ext4_find_extent()
4291 if (unlikely(path
[depth
].p_ext
== NULL
&& depth
!= 0)) {
4292 EXT4_ERROR_INODE(inode
, "bad extent address "
4293 "lblock: %lu, depth: %d pblock %lld",
4294 (unsigned long) map
->m_lblk
, depth
,
4295 path
[depth
].p_block
);
4300 ex
= path
[depth
].p_ext
;
4302 ext4_lblk_t ee_block
= le32_to_cpu(ex
->ee_block
);
4303 ext4_fsblk_t ee_start
= ext4_ext_pblock(ex
);
4304 unsigned short ee_len
;
4308 * unwritten extents are treated as holes, except that
4309 * we split out initialized portions during a write.
4311 ee_len
= ext4_ext_get_actual_len(ex
);
4313 trace_ext4_ext_show_extent(inode
, ee_block
, ee_start
, ee_len
);
4315 /* if found extent covers block, simply return it */
4316 if (in_range(map
->m_lblk
, ee_block
, ee_len
)) {
4317 newblock
= map
->m_lblk
- ee_block
+ ee_start
;
4318 /* number of remaining blocks in the extent */
4319 allocated
= ee_len
- (map
->m_lblk
- ee_block
);
4320 ext_debug("%u fit into %u:%d -> %llu\n", map
->m_lblk
,
4321 ee_block
, ee_len
, newblock
);
4324 * If the extent is initialized check whether the
4325 * caller wants to convert it to unwritten.
4327 if ((!ext4_ext_is_unwritten(ex
)) &&
4328 (flags
& EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
)) {
4329 allocated
= convert_initialized_extent(
4330 handle
, inode
, map
, &path
,
4331 flags
, allocated
, newblock
);
4333 } else if (!ext4_ext_is_unwritten(ex
))
4336 ret
= ext4_ext_handle_unwritten_extents(
4337 handle
, inode
, map
, &path
, flags
,
4338 allocated
, newblock
);
4347 if ((sbi
->s_cluster_ratio
> 1) &&
4348 ext4_find_delalloc_cluster(inode
, map
->m_lblk
))
4349 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
4352 * requested block isn't allocated yet;
4353 * we couldn't try to create block if create flag is zero
4355 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
4357 * put just found gap into cache to speed up
4358 * subsequent requests
4360 if ((flags
& EXT4_GET_BLOCKS_NO_PUT_HOLE
) == 0)
4361 ext4_ext_put_gap_in_cache(inode
, path
, map
->m_lblk
);
4366 * Okay, we need to do block allocation.
4368 map
->m_flags
&= ~EXT4_MAP_FROM_CLUSTER
;
4369 newex
.ee_block
= cpu_to_le32(map
->m_lblk
);
4370 cluster_offset
= EXT4_LBLK_COFF(sbi
, map
->m_lblk
);
4373 * If we are doing bigalloc, check to see if the extent returned
4374 * by ext4_find_extent() implies a cluster we can use.
4376 if (cluster_offset
&& ex
&&
4377 get_implied_cluster_alloc(inode
->i_sb
, map
, ex
, path
)) {
4378 ar
.len
= allocated
= map
->m_len
;
4379 newblock
= map
->m_pblk
;
4380 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
4381 goto got_allocated_blocks
;
4384 /* find neighbour allocated blocks */
4385 ar
.lleft
= map
->m_lblk
;
4386 err
= ext4_ext_search_left(inode
, path
, &ar
.lleft
, &ar
.pleft
);
4389 ar
.lright
= map
->m_lblk
;
4391 err
= ext4_ext_search_right(inode
, path
, &ar
.lright
, &ar
.pright
, &ex2
);
4395 /* Check if the extent after searching to the right implies a
4396 * cluster we can use. */
4397 if ((sbi
->s_cluster_ratio
> 1) && ex2
&&
4398 get_implied_cluster_alloc(inode
->i_sb
, map
, ex2
, path
)) {
4399 ar
.len
= allocated
= map
->m_len
;
4400 newblock
= map
->m_pblk
;
4401 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
4402 goto got_allocated_blocks
;
4406 * See if request is beyond maximum number of blocks we can have in
4407 * a single extent. For an initialized extent this limit is
4408 * EXT_INIT_MAX_LEN and for an unwritten extent this limit is
4409 * EXT_UNWRITTEN_MAX_LEN.
4411 if (map
->m_len
> EXT_INIT_MAX_LEN
&&
4412 !(flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
))
4413 map
->m_len
= EXT_INIT_MAX_LEN
;
4414 else if (map
->m_len
> EXT_UNWRITTEN_MAX_LEN
&&
4415 (flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
))
4416 map
->m_len
= EXT_UNWRITTEN_MAX_LEN
;
4418 /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
4419 newex
.ee_len
= cpu_to_le16(map
->m_len
);
4420 err
= ext4_ext_check_overlap(sbi
, inode
, &newex
, path
);
4422 allocated
= ext4_ext_get_actual_len(&newex
);
4424 allocated
= map
->m_len
;
4426 /* allocate new block */
4428 ar
.goal
= ext4_ext_find_goal(inode
, path
, map
->m_lblk
);
4429 ar
.logical
= map
->m_lblk
;
4431 * We calculate the offset from the beginning of the cluster
4432 * for the logical block number, since when we allocate a
4433 * physical cluster, the physical block should start at the
4434 * same offset from the beginning of the cluster. This is
4435 * needed so that future calls to get_implied_cluster_alloc()
4438 offset
= EXT4_LBLK_COFF(sbi
, map
->m_lblk
);
4439 ar
.len
= EXT4_NUM_B2C(sbi
, offset
+allocated
);
4441 ar
.logical
-= offset
;
4442 if (S_ISREG(inode
->i_mode
))
4443 ar
.flags
= EXT4_MB_HINT_DATA
;
4445 /* disable in-core preallocation for non-regular files */
4447 if (flags
& EXT4_GET_BLOCKS_NO_NORMALIZE
)
4448 ar
.flags
|= EXT4_MB_HINT_NOPREALLOC
;
4449 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
4450 ar
.flags
|= EXT4_MB_DELALLOC_RESERVED
;
4451 newblock
= ext4_mb_new_blocks(handle
, &ar
, &err
);
4454 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
4455 ar
.goal
, newblock
, allocated
);
4457 allocated_clusters
= ar
.len
;
4458 ar
.len
= EXT4_C2B(sbi
, ar
.len
) - offset
;
4459 if (ar
.len
> allocated
)
4462 got_allocated_blocks
:
4463 /* try to insert new extent into found leaf and return */
4464 ext4_ext_store_pblock(&newex
, newblock
+ offset
);
4465 newex
.ee_len
= cpu_to_le16(ar
.len
);
4466 /* Mark unwritten */
4467 if (flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
){
4468 ext4_ext_mark_unwritten(&newex
);
4469 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
4471 * io_end structure was created for every IO write to an
4472 * unwritten extent. To avoid unnecessary conversion,
4473 * here we flag the IO that really needs the conversion.
4474 * For non asycn direct IO case, flag the inode state
4475 * that we need to perform conversion when IO is done.
4477 if (flags
& EXT4_GET_BLOCKS_PRE_IO
)
4482 if ((flags
& EXT4_GET_BLOCKS_KEEP_SIZE
) == 0)
4483 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
,
4486 err
= ext4_ext_insert_extent(handle
, inode
, &path
,
4489 if (!err
&& set_unwritten
) {
4491 ext4_set_io_unwritten_flag(inode
, io
);
4493 ext4_set_inode_state(inode
,
4494 EXT4_STATE_DIO_UNWRITTEN
);
4497 if (err
&& free_on_err
) {
4498 int fb_flags
= flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
?
4499 EXT4_FREE_BLOCKS_NO_QUOT_UPDATE
: 0;
4500 /* free data blocks we just allocated */
4501 /* not a good idea to call discard here directly,
4502 * but otherwise we'd need to call it every free() */
4503 ext4_discard_preallocations(inode
);
4504 ext4_free_blocks(handle
, inode
, NULL
, newblock
,
4505 EXT4_C2B(sbi
, allocated_clusters
), fb_flags
);
4509 /* previous routine could use block we allocated */
4510 newblock
= ext4_ext_pblock(&newex
);
4511 allocated
= ext4_ext_get_actual_len(&newex
);
4512 if (allocated
> map
->m_len
)
4513 allocated
= map
->m_len
;
4514 map
->m_flags
|= EXT4_MAP_NEW
;
4517 * Update reserved blocks/metadata blocks after successful
4518 * block allocation which had been deferred till now.
4520 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) {
4521 unsigned int reserved_clusters
;
4523 * Check how many clusters we had reserved this allocated range
4525 reserved_clusters
= get_reserved_cluster_alloc(inode
,
4526 map
->m_lblk
, allocated
);
4527 if (map
->m_flags
& EXT4_MAP_FROM_CLUSTER
) {
4528 if (reserved_clusters
) {
4530 * We have clusters reserved for this range.
4531 * But since we are not doing actual allocation
4532 * and are simply using blocks from previously
4533 * allocated cluster, we should release the
4534 * reservation and not claim quota.
4536 ext4_da_update_reserve_space(inode
,
4537 reserved_clusters
, 0);
4540 BUG_ON(allocated_clusters
< reserved_clusters
);
4541 if (reserved_clusters
< allocated_clusters
) {
4542 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4543 int reservation
= allocated_clusters
-
4546 * It seems we claimed few clusters outside of
4547 * the range of this allocation. We should give
4548 * it back to the reservation pool. This can
4549 * happen in the following case:
4551 * * Suppose s_cluster_ratio is 4 (i.e., each
4552 * cluster has 4 blocks. Thus, the clusters
4553 * are [0-3],[4-7],[8-11]...
4554 * * First comes delayed allocation write for
4555 * logical blocks 10 & 11. Since there were no
4556 * previous delayed allocated blocks in the
4557 * range [8-11], we would reserve 1 cluster
4559 * * Next comes write for logical blocks 3 to 8.
4560 * In this case, we will reserve 2 clusters
4561 * (for [0-3] and [4-7]; and not for [8-11] as
4562 * that range has a delayed allocated blocks.
4563 * Thus total reserved clusters now becomes 3.
4564 * * Now, during the delayed allocation writeout
4565 * time, we will first write blocks [3-8] and
4566 * allocate 3 clusters for writing these
4567 * blocks. Also, we would claim all these
4568 * three clusters above.
4569 * * Now when we come here to writeout the
4570 * blocks [10-11], we would expect to claim
4571 * the reservation of 1 cluster we had made
4572 * (and we would claim it since there are no
4573 * more delayed allocated blocks in the range
4574 * [8-11]. But our reserved cluster count had
4575 * already gone to 0.
4577 * Thus, at the step 4 above when we determine
4578 * that there are still some unwritten delayed
4579 * allocated blocks outside of our current
4580 * block range, we should increment the
4581 * reserved clusters count so that when the
4582 * remaining blocks finally gets written, we
4585 dquot_reserve_block(inode
,
4586 EXT4_C2B(sbi
, reservation
));
4587 spin_lock(&ei
->i_block_reservation_lock
);
4588 ei
->i_reserved_data_blocks
+= reservation
;
4589 spin_unlock(&ei
->i_block_reservation_lock
);
4592 * We will claim quota for all newly allocated blocks.
4593 * We're updating the reserved space *after* the
4594 * correction above so we do not accidentally free
4595 * all the metadata reservation because we might
4596 * actually need it later on.
4598 ext4_da_update_reserve_space(inode
, allocated_clusters
,
4604 * Cache the extent and update transaction to commit on fdatasync only
4605 * when it is _not_ an unwritten extent.
4607 if ((flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
) == 0)
4608 ext4_update_inode_fsync_trans(handle
, inode
, 1);
4610 ext4_update_inode_fsync_trans(handle
, inode
, 0);
4612 if (allocated
> map
->m_len
)
4613 allocated
= map
->m_len
;
4614 ext4_ext_show_leaf(inode
, path
);
4615 map
->m_flags
|= EXT4_MAP_MAPPED
;
4616 map
->m_pblk
= newblock
;
4617 map
->m_len
= allocated
;
4619 ext4_ext_drop_refs(path
);
4622 trace_ext4_ext_map_blocks_exit(inode
, flags
, map
,
4623 err
? err
: allocated
);
4624 ext4_es_lru_add(inode
);
4625 return err
? err
: allocated
;
4628 void ext4_ext_truncate(handle_t
*handle
, struct inode
*inode
)
4630 struct super_block
*sb
= inode
->i_sb
;
4631 ext4_lblk_t last_block
;
4635 * TODO: optimization is possible here.
4636 * Probably we need not scan at all,
4637 * because page truncation is enough.
4640 /* we have to know where to truncate from in crash case */
4641 EXT4_I(inode
)->i_disksize
= inode
->i_size
;
4642 ext4_mark_inode_dirty(handle
, inode
);
4644 last_block
= (inode
->i_size
+ sb
->s_blocksize
- 1)
4645 >> EXT4_BLOCK_SIZE_BITS(sb
);
4647 err
= ext4_es_remove_extent(inode
, last_block
,
4648 EXT_MAX_BLOCKS
- last_block
);
4649 if (err
== -ENOMEM
) {
4651 congestion_wait(BLK_RW_ASYNC
, HZ
/50);
4655 ext4_std_error(inode
->i_sb
, err
);
4658 err
= ext4_ext_remove_space(inode
, last_block
, EXT_MAX_BLOCKS
- 1);
4659 ext4_std_error(inode
->i_sb
, err
);
4662 static int ext4_alloc_file_blocks(struct file
*file
, ext4_lblk_t offset
,
4663 ext4_lblk_t len
, loff_t new_size
,
4664 int flags
, int mode
)
4666 struct inode
*inode
= file_inode(file
);
4671 struct ext4_map_blocks map
;
4672 unsigned int credits
;
4675 map
.m_lblk
= offset
;
4678 * Don't normalize the request if it can fit in one extent so
4679 * that it doesn't get unnecessarily split into multiple
4682 if (len
<= EXT_UNWRITTEN_MAX_LEN
)
4683 flags
|= EXT4_GET_BLOCKS_NO_NORMALIZE
;
4686 * credits to insert 1 extent into extent tree
4688 credits
= ext4_chunk_trans_blocks(inode
, len
);
4691 while (ret
>= 0 && len
) {
4692 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
4694 if (IS_ERR(handle
)) {
4695 ret
= PTR_ERR(handle
);
4698 ret
= ext4_map_blocks(handle
, inode
, &map
, flags
);
4700 ext4_debug("inode #%lu: block %u: len %u: "
4701 "ext4_ext_map_blocks returned %d",
4702 inode
->i_ino
, map
.m_lblk
,
4704 ext4_mark_inode_dirty(handle
, inode
);
4705 ret2
= ext4_journal_stop(handle
);
4709 map
.m_len
= len
= len
- ret
;
4710 epos
= (loff_t
)map
.m_lblk
<< inode
->i_blkbits
;
4711 inode
->i_ctime
= ext4_current_time(inode
);
4713 if (epos
> new_size
)
4715 if (ext4_update_inode_size(inode
, epos
) & 0x1)
4716 inode
->i_mtime
= inode
->i_ctime
;
4718 if (epos
> inode
->i_size
)
4719 ext4_set_inode_flag(inode
,
4720 EXT4_INODE_EOFBLOCKS
);
4722 ext4_mark_inode_dirty(handle
, inode
);
4723 ret2
= ext4_journal_stop(handle
);
4727 if (ret
== -ENOSPC
&&
4728 ext4_should_retry_alloc(inode
->i_sb
, &retries
)) {
4733 return ret
> 0 ? ret2
: ret
;
4736 static long ext4_zero_range(struct file
*file
, loff_t offset
,
4737 loff_t len
, int mode
)
4739 struct inode
*inode
= file_inode(file
);
4740 handle_t
*handle
= NULL
;
4741 unsigned int max_blocks
;
4742 loff_t new_size
= 0;
4746 int partial_begin
, partial_end
;
4749 struct address_space
*mapping
= inode
->i_mapping
;
4750 unsigned int blkbits
= inode
->i_blkbits
;
4752 trace_ext4_zero_range(inode
, offset
, len
, mode
);
4754 if (!S_ISREG(inode
->i_mode
))
4757 /* Call ext4_force_commit to flush all data in case of data=journal. */
4758 if (ext4_should_journal_data(inode
)) {
4759 ret
= ext4_force_commit(inode
->i_sb
);
4765 * Write out all dirty pages to avoid race conditions
4766 * Then release them.
4768 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
4769 ret
= filemap_write_and_wait_range(mapping
, offset
,
4776 * Round up offset. This is not fallocate, we neet to zero out
4777 * blocks, so convert interior block aligned part of the range to
4778 * unwritten and possibly manually zero out unaligned parts of the
4781 start
= round_up(offset
, 1 << blkbits
);
4782 end
= round_down((offset
+ len
), 1 << blkbits
);
4784 if (start
< offset
|| end
> offset
+ len
)
4786 partial_begin
= offset
& ((1 << blkbits
) - 1);
4787 partial_end
= (offset
+ len
) & ((1 << blkbits
) - 1);
4789 lblk
= start
>> blkbits
;
4790 max_blocks
= (end
>> blkbits
);
4791 if (max_blocks
< lblk
)
4796 flags
= EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT
|
4797 EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
|
4799 if (mode
& FALLOC_FL_KEEP_SIZE
)
4800 flags
|= EXT4_GET_BLOCKS_KEEP_SIZE
;
4802 mutex_lock(&inode
->i_mutex
);
4805 * Indirect files do not support unwritten extnets
4807 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))) {
4812 if (!(mode
& FALLOC_FL_KEEP_SIZE
) &&
4813 offset
+ len
> i_size_read(inode
)) {
4814 new_size
= offset
+ len
;
4815 ret
= inode_newsize_ok(inode
, new_size
);
4819 * If we have a partial block after EOF we have to allocate
4826 if (max_blocks
> 0) {
4828 /* Now release the pages and zero block aligned part of pages*/
4829 truncate_pagecache_range(inode
, start
, end
- 1);
4830 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
4832 /* Wait all existing dio workers, newcomers will block on i_mutex */
4833 ext4_inode_block_unlocked_dio(inode
);
4834 inode_dio_wait(inode
);
4836 ret
= ext4_alloc_file_blocks(file
, lblk
, max_blocks
, new_size
,
4841 * Remove entire range from the extent status tree.
4843 * ext4_es_remove_extent(inode, lblk, max_blocks) is
4844 * NOT sufficient. I'm not sure why this is the case,
4845 * but let's be conservative and remove the extent
4846 * status tree for the entire inode. There should be
4847 * no outstanding delalloc extents thanks to the
4848 * filemap_write_and_wait_range() call above.
4850 ret
= ext4_es_remove_extent(inode
, 0, EXT_MAX_BLOCKS
);
4854 if (!partial_begin
&& !partial_end
)
4858 * In worst case we have to writeout two nonadjacent unwritten
4859 * blocks and update the inode
4861 credits
= (2 * ext4_ext_index_trans_blocks(inode
, 2)) + 1;
4862 if (ext4_should_journal_data(inode
))
4864 handle
= ext4_journal_start(inode
, EXT4_HT_MISC
, credits
);
4865 if (IS_ERR(handle
)) {
4866 ret
= PTR_ERR(handle
);
4867 ext4_std_error(inode
->i_sb
, ret
);
4871 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
4873 ext4_update_inode_size(inode
, new_size
);
4876 * Mark that we allocate beyond EOF so the subsequent truncate
4877 * can proceed even if the new size is the same as i_size.
4879 if ((offset
+ len
) > i_size_read(inode
))
4880 ext4_set_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
4882 ext4_mark_inode_dirty(handle
, inode
);
4884 /* Zero out partial block at the edges of the range */
4885 ret
= ext4_zero_partial_blocks(handle
, inode
, offset
, len
);
4887 if (file
->f_flags
& O_SYNC
)
4888 ext4_handle_sync(handle
);
4890 ext4_journal_stop(handle
);
4892 ext4_inode_resume_unlocked_dio(inode
);
4894 mutex_unlock(&inode
->i_mutex
);
4899 * preallocate space for a file. This implements ext4's fallocate file
4900 * operation, which gets called from sys_fallocate system call.
4901 * For block-mapped files, posix_fallocate should fall back to the method
4902 * of writing zeroes to the required new blocks (the same behavior which is
4903 * expected for file systems which do not support fallocate() system call).
4905 long ext4_fallocate(struct file
*file
, int mode
, loff_t offset
, loff_t len
)
4907 struct inode
*inode
= file_inode(file
);
4908 loff_t new_size
= 0;
4909 unsigned int max_blocks
;
4913 unsigned int blkbits
= inode
->i_blkbits
;
4915 /* Return error if mode is not supported */
4916 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
|
4917 FALLOC_FL_COLLAPSE_RANGE
| FALLOC_FL_ZERO_RANGE
))
4920 if (mode
& FALLOC_FL_PUNCH_HOLE
)
4921 return ext4_punch_hole(inode
, offset
, len
);
4923 ret
= ext4_convert_inline_data(inode
);
4928 * currently supporting (pre)allocate mode for extent-based
4931 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4934 if (mode
& FALLOC_FL_COLLAPSE_RANGE
)
4935 return ext4_collapse_range(inode
, offset
, len
);
4937 if (mode
& FALLOC_FL_ZERO_RANGE
)
4938 return ext4_zero_range(file
, offset
, len
, mode
);
4940 trace_ext4_fallocate_enter(inode
, offset
, len
, mode
);
4941 lblk
= offset
>> blkbits
;
4943 * We can't just convert len to max_blocks because
4944 * If blocksize = 4096 offset = 3072 and len = 2048
4946 max_blocks
= (EXT4_BLOCK_ALIGN(len
+ offset
, blkbits
) >> blkbits
)
4949 flags
= EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT
;
4950 if (mode
& FALLOC_FL_KEEP_SIZE
)
4951 flags
|= EXT4_GET_BLOCKS_KEEP_SIZE
;
4953 mutex_lock(&inode
->i_mutex
);
4955 if (!(mode
& FALLOC_FL_KEEP_SIZE
) &&
4956 offset
+ len
> i_size_read(inode
)) {
4957 new_size
= offset
+ len
;
4958 ret
= inode_newsize_ok(inode
, new_size
);
4963 ret
= ext4_alloc_file_blocks(file
, lblk
, max_blocks
, new_size
,
4968 if (file
->f_flags
& O_SYNC
&& EXT4_SB(inode
->i_sb
)->s_journal
) {
4969 ret
= jbd2_complete_transaction(EXT4_SB(inode
->i_sb
)->s_journal
,
4970 EXT4_I(inode
)->i_sync_tid
);
4973 mutex_unlock(&inode
->i_mutex
);
4974 trace_ext4_fallocate_exit(inode
, offset
, max_blocks
, ret
);
4979 * This function convert a range of blocks to written extents
4980 * The caller of this function will pass the start offset and the size.
4981 * all unwritten extents within this range will be converted to
4984 * This function is called from the direct IO end io call back
4985 * function, to convert the fallocated extents after IO is completed.
4986 * Returns 0 on success.
4988 int ext4_convert_unwritten_extents(handle_t
*handle
, struct inode
*inode
,
4989 loff_t offset
, ssize_t len
)
4991 unsigned int max_blocks
;
4994 struct ext4_map_blocks map
;
4995 unsigned int credits
, blkbits
= inode
->i_blkbits
;
4997 map
.m_lblk
= offset
>> blkbits
;
4999 * We can't just convert len to max_blocks because
5000 * If blocksize = 4096 offset = 3072 and len = 2048
5002 max_blocks
= ((EXT4_BLOCK_ALIGN(len
+ offset
, blkbits
) >> blkbits
) -
5005 * This is somewhat ugly but the idea is clear: When transaction is
5006 * reserved, everything goes into it. Otherwise we rather start several
5007 * smaller transactions for conversion of each extent separately.
5010 handle
= ext4_journal_start_reserved(handle
,
5011 EXT4_HT_EXT_CONVERT
);
5013 return PTR_ERR(handle
);
5017 * credits to insert 1 extent into extent tree
5019 credits
= ext4_chunk_trans_blocks(inode
, max_blocks
);
5021 while (ret
>= 0 && ret
< max_blocks
) {
5023 map
.m_len
= (max_blocks
-= ret
);
5025 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
5027 if (IS_ERR(handle
)) {
5028 ret
= PTR_ERR(handle
);
5032 ret
= ext4_map_blocks(handle
, inode
, &map
,
5033 EXT4_GET_BLOCKS_IO_CONVERT_EXT
);
5035 ext4_warning(inode
->i_sb
,
5036 "inode #%lu: block %u: len %u: "
5037 "ext4_ext_map_blocks returned %d",
5038 inode
->i_ino
, map
.m_lblk
,
5040 ext4_mark_inode_dirty(handle
, inode
);
5042 ret2
= ext4_journal_stop(handle
);
5043 if (ret
<= 0 || ret2
)
5047 ret2
= ext4_journal_stop(handle
);
5048 return ret
> 0 ? ret2
: ret
;
5052 * If newes is not existing extent (newes->ec_pblk equals zero) find
5053 * delayed extent at start of newes and update newes accordingly and
5054 * return start of the next delayed extent.
5056 * If newes is existing extent (newes->ec_pblk is not equal zero)
5057 * return start of next delayed extent or EXT_MAX_BLOCKS if no delayed
5058 * extent found. Leave newes unmodified.
5060 static int ext4_find_delayed_extent(struct inode
*inode
,
5061 struct extent_status
*newes
)
5063 struct extent_status es
;
5064 ext4_lblk_t block
, next_del
;
5066 if (newes
->es_pblk
== 0) {
5067 ext4_es_find_delayed_extent_range(inode
, newes
->es_lblk
,
5068 newes
->es_lblk
+ newes
->es_len
- 1, &es
);
5071 * No extent in extent-tree contains block @newes->es_pblk,
5072 * then the block may stay in 1)a hole or 2)delayed-extent.
5078 if (es
.es_lblk
> newes
->es_lblk
) {
5080 newes
->es_len
= min(es
.es_lblk
- newes
->es_lblk
,
5085 newes
->es_len
= es
.es_lblk
+ es
.es_len
- newes
->es_lblk
;
5088 block
= newes
->es_lblk
+ newes
->es_len
;
5089 ext4_es_find_delayed_extent_range(inode
, block
, EXT_MAX_BLOCKS
, &es
);
5091 next_del
= EXT_MAX_BLOCKS
;
5093 next_del
= es
.es_lblk
;
5097 /* fiemap flags we can handle specified here */
5098 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
5100 static int ext4_xattr_fiemap(struct inode
*inode
,
5101 struct fiemap_extent_info
*fieinfo
)
5105 __u32 flags
= FIEMAP_EXTENT_LAST
;
5106 int blockbits
= inode
->i_sb
->s_blocksize_bits
;
5110 if (ext4_test_inode_state(inode
, EXT4_STATE_XATTR
)) {
5111 struct ext4_iloc iloc
;
5112 int offset
; /* offset of xattr in inode */
5114 error
= ext4_get_inode_loc(inode
, &iloc
);
5117 physical
= (__u64
)iloc
.bh
->b_blocknr
<< blockbits
;
5118 offset
= EXT4_GOOD_OLD_INODE_SIZE
+
5119 EXT4_I(inode
)->i_extra_isize
;
5121 length
= EXT4_SB(inode
->i_sb
)->s_inode_size
- offset
;
5122 flags
|= FIEMAP_EXTENT_DATA_INLINE
;
5124 } else { /* external block */
5125 physical
= (__u64
)EXT4_I(inode
)->i_file_acl
<< blockbits
;
5126 length
= inode
->i_sb
->s_blocksize
;
5130 error
= fiemap_fill_next_extent(fieinfo
, 0, physical
,
5132 return (error
< 0 ? error
: 0);
5135 int ext4_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
5136 __u64 start
, __u64 len
)
5138 ext4_lblk_t start_blk
;
5141 if (ext4_has_inline_data(inode
)) {
5144 error
= ext4_inline_data_fiemap(inode
, fieinfo
, &has_inline
);
5150 if (fieinfo
->fi_flags
& FIEMAP_FLAG_CACHE
) {
5151 error
= ext4_ext_precache(inode
);
5156 /* fallback to generic here if not in extents fmt */
5157 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
5158 return generic_block_fiemap(inode
, fieinfo
, start
, len
,
5161 if (fiemap_check_flags(fieinfo
, EXT4_FIEMAP_FLAGS
))
5164 if (fieinfo
->fi_flags
& FIEMAP_FLAG_XATTR
) {
5165 error
= ext4_xattr_fiemap(inode
, fieinfo
);
5167 ext4_lblk_t len_blks
;
5170 start_blk
= start
>> inode
->i_sb
->s_blocksize_bits
;
5171 last_blk
= (start
+ len
- 1) >> inode
->i_sb
->s_blocksize_bits
;
5172 if (last_blk
>= EXT_MAX_BLOCKS
)
5173 last_blk
= EXT_MAX_BLOCKS
-1;
5174 len_blks
= ((ext4_lblk_t
) last_blk
) - start_blk
+ 1;
5177 * Walk the extent tree gathering extent information
5178 * and pushing extents back to the user.
5180 error
= ext4_fill_fiemap_extents(inode
, start_blk
,
5183 ext4_es_lru_add(inode
);
5189 * Function to access the path buffer for marking it dirty.
5190 * It also checks if there are sufficient credits left in the journal handle
5194 ext4_access_path(handle_t
*handle
, struct inode
*inode
,
5195 struct ext4_ext_path
*path
)
5199 if (!ext4_handle_valid(handle
))
5203 * Check if need to extend journal credits
5204 * 3 for leaf, sb, and inode plus 2 (bmap and group
5205 * descriptor) for each block group; assume two block
5208 if (handle
->h_buffer_credits
< 7) {
5209 credits
= ext4_writepage_trans_blocks(inode
);
5210 err
= ext4_ext_truncate_extend_restart(handle
, inode
, credits
);
5211 /* EAGAIN is success */
5212 if (err
&& err
!= -EAGAIN
)
5216 err
= ext4_ext_get_access(handle
, inode
, path
);
5221 * ext4_ext_shift_path_extents:
5222 * Shift the extents of a path structure lying between path[depth].p_ext
5223 * and EXT_LAST_EXTENT(path[depth].p_hdr) downwards, by subtracting shift
5224 * from starting block for each extent.
5227 ext4_ext_shift_path_extents(struct ext4_ext_path
*path
, ext4_lblk_t shift
,
5228 struct inode
*inode
, handle_t
*handle
,
5232 struct ext4_extent
*ex_start
, *ex_last
;
5234 depth
= path
->p_depth
;
5236 while (depth
>= 0) {
5237 if (depth
== path
->p_depth
) {
5238 ex_start
= path
[depth
].p_ext
;
5242 ex_last
= EXT_LAST_EXTENT(path
[depth
].p_hdr
);
5246 err
= ext4_access_path(handle
, inode
, path
+ depth
);
5250 if (ex_start
== EXT_FIRST_EXTENT(path
[depth
].p_hdr
))
5253 *start
= le32_to_cpu(ex_last
->ee_block
) +
5254 ext4_ext_get_actual_len(ex_last
);
5256 while (ex_start
<= ex_last
) {
5257 le32_add_cpu(&ex_start
->ee_block
, -shift
);
5258 /* Try to merge to the left. */
5260 EXT_FIRST_EXTENT(path
[depth
].p_hdr
)) &&
5261 ext4_ext_try_to_merge_right(inode
,
5262 path
, ex_start
- 1))
5267 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
5271 if (--depth
< 0 || !update
)
5275 /* Update index too */
5276 err
= ext4_access_path(handle
, inode
, path
+ depth
);
5280 le32_add_cpu(&path
[depth
].p_idx
->ei_block
, -shift
);
5281 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
5285 /* we are done if current index is not a starting index */
5286 if (path
[depth
].p_idx
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
))
5297 * ext4_ext_shift_extents:
5298 * All the extents which lies in the range from start to the last allocated
5299 * block for the file are shifted downwards by shift blocks.
5300 * On success, 0 is returned, error otherwise.
5303 ext4_ext_shift_extents(struct inode
*inode
, handle_t
*handle
,
5304 ext4_lblk_t start
, ext4_lblk_t shift
)
5306 struct ext4_ext_path
*path
;
5308 struct ext4_extent
*extent
;
5309 ext4_lblk_t stop_block
;
5310 ext4_lblk_t ex_start
, ex_end
;
5312 /* Let path point to the last extent */
5313 path
= ext4_find_extent(inode
, EXT_MAX_BLOCKS
- 1, NULL
, 0);
5315 return PTR_ERR(path
);
5317 depth
= path
->p_depth
;
5318 extent
= path
[depth
].p_ext
;
5322 stop_block
= le32_to_cpu(extent
->ee_block
) +
5323 ext4_ext_get_actual_len(extent
);
5325 /* Nothing to shift, if hole is at the end of file */
5326 if (start
>= stop_block
)
5330 * Don't start shifting extents until we make sure the hole is big
5331 * enough to accomodate the shift.
5333 path
= ext4_find_extent(inode
, start
- 1, &path
, 0);
5335 return PTR_ERR(path
);
5336 depth
= path
->p_depth
;
5337 extent
= path
[depth
].p_ext
;
5339 ex_start
= le32_to_cpu(extent
->ee_block
);
5340 ex_end
= le32_to_cpu(extent
->ee_block
) +
5341 ext4_ext_get_actual_len(extent
);
5347 if ((start
== ex_start
&& shift
> ex_start
) ||
5348 (shift
> start
- ex_end
))
5351 /* Its safe to start updating extents */
5352 while (start
< stop_block
) {
5353 path
= ext4_find_extent(inode
, start
, &path
, 0);
5355 return PTR_ERR(path
);
5356 depth
= path
->p_depth
;
5357 extent
= path
[depth
].p_ext
;
5359 EXT4_ERROR_INODE(inode
, "unexpected hole at %lu",
5360 (unsigned long) start
);
5363 if (start
> le32_to_cpu(extent
->ee_block
)) {
5364 /* Hole, move to the next extent */
5365 if (extent
< EXT_LAST_EXTENT(path
[depth
].p_hdr
)) {
5366 path
[depth
].p_ext
++;
5368 start
= ext4_ext_next_allocated_block(path
);
5372 ret
= ext4_ext_shift_path_extents(path
, shift
, inode
,
5378 ext4_ext_drop_refs(path
);
5384 * ext4_collapse_range:
5385 * This implements the fallocate's collapse range functionality for ext4
5386 * Returns: 0 and non-zero on error.
5388 int ext4_collapse_range(struct inode
*inode
, loff_t offset
, loff_t len
)
5390 struct super_block
*sb
= inode
->i_sb
;
5391 ext4_lblk_t punch_start
, punch_stop
;
5393 unsigned int credits
;
5394 loff_t new_size
, ioffset
;
5397 /* Collapse range works only on fs block size aligned offsets. */
5398 if (offset
& (EXT4_CLUSTER_SIZE(sb
) - 1) ||
5399 len
& (EXT4_CLUSTER_SIZE(sb
) - 1))
5402 if (!S_ISREG(inode
->i_mode
))
5405 trace_ext4_collapse_range(inode
, offset
, len
);
5407 punch_start
= offset
>> EXT4_BLOCK_SIZE_BITS(sb
);
5408 punch_stop
= (offset
+ len
) >> EXT4_BLOCK_SIZE_BITS(sb
);
5410 /* Call ext4_force_commit to flush all data in case of data=journal. */
5411 if (ext4_should_journal_data(inode
)) {
5412 ret
= ext4_force_commit(inode
->i_sb
);
5418 * Need to round down offset to be aligned with page size boundary
5419 * for page size > block size.
5421 ioffset
= round_down(offset
, PAGE_SIZE
);
5423 /* Write out all dirty pages */
5424 ret
= filemap_write_and_wait_range(inode
->i_mapping
, ioffset
,
5429 /* Take mutex lock */
5430 mutex_lock(&inode
->i_mutex
);
5433 * There is no need to overlap collapse range with EOF, in which case
5434 * it is effectively a truncate operation
5436 if (offset
+ len
>= i_size_read(inode
)) {
5441 /* Currently just for extent based files */
5442 if (!ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
5447 truncate_pagecache(inode
, ioffset
);
5449 /* Wait for existing dio to complete */
5450 ext4_inode_block_unlocked_dio(inode
);
5451 inode_dio_wait(inode
);
5453 credits
= ext4_writepage_trans_blocks(inode
);
5454 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
5455 if (IS_ERR(handle
)) {
5456 ret
= PTR_ERR(handle
);
5460 down_write(&EXT4_I(inode
)->i_data_sem
);
5461 ext4_discard_preallocations(inode
);
5463 ret
= ext4_es_remove_extent(inode
, punch_start
,
5464 EXT_MAX_BLOCKS
- punch_start
);
5466 up_write(&EXT4_I(inode
)->i_data_sem
);
5470 ret
= ext4_ext_remove_space(inode
, punch_start
, punch_stop
- 1);
5472 up_write(&EXT4_I(inode
)->i_data_sem
);
5475 ext4_discard_preallocations(inode
);
5477 ret
= ext4_ext_shift_extents(inode
, handle
, punch_stop
,
5478 punch_stop
- punch_start
);
5480 up_write(&EXT4_I(inode
)->i_data_sem
);
5484 new_size
= i_size_read(inode
) - len
;
5485 i_size_write(inode
, new_size
);
5486 EXT4_I(inode
)->i_disksize
= new_size
;
5488 up_write(&EXT4_I(inode
)->i_data_sem
);
5490 ext4_handle_sync(handle
);
5491 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
5492 ext4_mark_inode_dirty(handle
, inode
);
5495 ext4_journal_stop(handle
);
5497 ext4_inode_resume_unlocked_dio(inode
);
5499 mutex_unlock(&inode
->i_mutex
);
5504 * ext4_swap_extents - Swap extents between two inodes
5506 * @inode1: First inode
5507 * @inode2: Second inode
5508 * @lblk1: Start block for first inode
5509 * @lblk2: Start block for second inode
5510 * @count: Number of blocks to swap
5511 * @mark_unwritten: Mark second inode's extents as unwritten after swap
5512 * @erp: Pointer to save error value
5514 * This helper routine does exactly what is promise "swap extents". All other
5515 * stuff such as page-cache locking consistency, bh mapping consistency or
5516 * extent's data copying must be performed by caller.
5518 * i_mutex is held for both inodes
5519 * i_data_sem is locked for write for both inodes
5521 * All pages from requested range are locked for both inodes
5524 ext4_swap_extents(handle_t
*handle
, struct inode
*inode1
,
5525 struct inode
*inode2
, ext4_lblk_t lblk1
, ext4_lblk_t lblk2
,
5526 ext4_lblk_t count
, int unwritten
, int *erp
)
5528 struct ext4_ext_path
*path1
= NULL
;
5529 struct ext4_ext_path
*path2
= NULL
;
5530 int replaced_count
= 0;
5532 BUG_ON(!rwsem_is_locked(&EXT4_I(inode1
)->i_data_sem
));
5533 BUG_ON(!rwsem_is_locked(&EXT4_I(inode2
)->i_data_sem
));
5534 BUG_ON(!mutex_is_locked(&inode1
->i_mutex
));
5535 BUG_ON(!mutex_is_locked(&inode1
->i_mutex
));
5537 *erp
= ext4_es_remove_extent(inode1
, lblk1
, count
);
5540 *erp
= ext4_es_remove_extent(inode2
, lblk2
, count
);
5545 struct ext4_extent
*ex1
, *ex2
, tmp_ex
;
5546 ext4_lblk_t e1_blk
, e2_blk
;
5547 int e1_len
, e2_len
, len
;
5550 path1
= ext4_find_extent(inode1
, lblk1
, NULL
, EXT4_EX_NOCACHE
);
5551 if (unlikely(IS_ERR(path1
))) {
5552 *erp
= PTR_ERR(path1
);
5558 path2
= ext4_find_extent(inode2
, lblk2
, NULL
, EXT4_EX_NOCACHE
);
5559 if (unlikely(IS_ERR(path2
))) {
5560 *erp
= PTR_ERR(path2
);
5564 ex1
= path1
[path1
->p_depth
].p_ext
;
5565 ex2
= path2
[path2
->p_depth
].p_ext
;
5566 /* Do we have somthing to swap ? */
5567 if (unlikely(!ex2
|| !ex1
))
5570 e1_blk
= le32_to_cpu(ex1
->ee_block
);
5571 e2_blk
= le32_to_cpu(ex2
->ee_block
);
5572 e1_len
= ext4_ext_get_actual_len(ex1
);
5573 e2_len
= ext4_ext_get_actual_len(ex2
);
5576 if (!in_range(lblk1
, e1_blk
, e1_len
) ||
5577 !in_range(lblk2
, e2_blk
, e2_len
)) {
5578 ext4_lblk_t next1
, next2
;
5580 /* if hole after extent, then go to next extent */
5581 next1
= ext4_ext_next_allocated_block(path1
);
5582 next2
= ext4_ext_next_allocated_block(path2
);
5583 /* If hole before extent, then shift to that extent */
5588 /* Do we have something to swap */
5589 if (next1
== EXT_MAX_BLOCKS
|| next2
== EXT_MAX_BLOCKS
)
5591 /* Move to the rightest boundary */
5592 len
= next1
- lblk1
;
5593 if (len
< next2
- lblk2
)
5594 len
= next2
- lblk2
;
5603 /* Prepare left boundary */
5604 if (e1_blk
< lblk1
) {
5606 *erp
= ext4_force_split_extent_at(handle
, inode1
,
5611 if (e2_blk
< lblk2
) {
5613 *erp
= ext4_force_split_extent_at(handle
, inode2
,
5618 /* ext4_split_extent_at() may result in leaf extent split,
5619 * path must to be revalidated. */
5623 /* Prepare right boundary */
5625 if (len
> e1_blk
+ e1_len
- lblk1
)
5626 len
= e1_blk
+ e1_len
- lblk1
;
5627 if (len
> e2_blk
+ e2_len
- lblk2
)
5628 len
= e2_blk
+ e2_len
- lblk2
;
5630 if (len
!= e1_len
) {
5632 *erp
= ext4_force_split_extent_at(handle
, inode1
,
5633 &path1
, lblk1
+ len
, 0);
5637 if (len
!= e2_len
) {
5639 *erp
= ext4_force_split_extent_at(handle
, inode2
,
5640 &path2
, lblk2
+ len
, 0);
5644 /* ext4_split_extent_at() may result in leaf extent split,
5645 * path must to be revalidated. */
5649 BUG_ON(e2_len
!= e1_len
);
5650 *erp
= ext4_ext_get_access(handle
, inode1
, path1
+ path1
->p_depth
);
5653 *erp
= ext4_ext_get_access(handle
, inode2
, path2
+ path2
->p_depth
);
5657 /* Both extents are fully inside boundaries. Swap it now */
5659 ext4_ext_store_pblock(ex1
, ext4_ext_pblock(ex2
));
5660 ext4_ext_store_pblock(ex2
, ext4_ext_pblock(&tmp_ex
));
5661 ex1
->ee_len
= cpu_to_le16(e2_len
);
5662 ex2
->ee_len
= cpu_to_le16(e1_len
);
5664 ext4_ext_mark_unwritten(ex2
);
5665 if (ext4_ext_is_unwritten(&tmp_ex
))
5666 ext4_ext_mark_unwritten(ex1
);
5668 ext4_ext_try_to_merge(handle
, inode2
, path2
, ex2
);
5669 ext4_ext_try_to_merge(handle
, inode1
, path1
, ex1
);
5670 *erp
= ext4_ext_dirty(handle
, inode2
, path2
+
5674 *erp
= ext4_ext_dirty(handle
, inode1
, path1
+
5677 * Looks scarry ah..? second inode already points to new blocks,
5678 * and it was successfully dirtied. But luckily error may happen
5679 * only due to journal error, so full transaction will be
5686 replaced_count
+= len
;
5690 ext4_ext_drop_refs(path1
);
5692 ext4_ext_drop_refs(path2
);
5694 path1
= path2
= NULL
;
5696 return replaced_count
;