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_RO_COMPAT_FEATURE(inode
->i_sb
,
77 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
))
80 et
= find_ext4_extent_tail(eh
);
81 if (et
->et_checksum
!= ext4_extent_block_csum(inode
, eh
))
86 static void ext4_extent_block_csum_set(struct inode
*inode
,
87 struct ext4_extent_header
*eh
)
89 struct ext4_extent_tail
*et
;
91 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
92 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
))
95 et
= find_ext4_extent_tail(eh
);
96 et
->et_checksum
= ext4_extent_block_csum(inode
, eh
);
99 static int ext4_split_extent(handle_t
*handle
,
101 struct ext4_ext_path
**ppath
,
102 struct ext4_map_blocks
*map
,
106 static int ext4_split_extent_at(handle_t
*handle
,
108 struct ext4_ext_path
**ppath
,
113 static int ext4_find_delayed_extent(struct inode
*inode
,
114 struct extent_status
*newes
);
116 static int ext4_ext_truncate_extend_restart(handle_t
*handle
,
122 if (!ext4_handle_valid(handle
))
124 if (handle
->h_buffer_credits
> needed
)
126 err
= ext4_journal_extend(handle
, needed
);
129 err
= ext4_truncate_restart_trans(handle
, inode
, needed
);
141 static int ext4_ext_get_access(handle_t
*handle
, struct inode
*inode
,
142 struct ext4_ext_path
*path
)
145 /* path points to block */
146 BUFFER_TRACE(path
->p_bh
, "get_write_access");
147 return ext4_journal_get_write_access(handle
, path
->p_bh
);
149 /* path points to leaf/index in inode body */
150 /* we use in-core data, no need to protect them */
160 int __ext4_ext_dirty(const char *where
, unsigned int line
, handle_t
*handle
,
161 struct inode
*inode
, struct ext4_ext_path
*path
)
165 WARN_ON(!rwsem_is_locked(&EXT4_I(inode
)->i_data_sem
));
167 ext4_extent_block_csum_set(inode
, ext_block_hdr(path
->p_bh
));
168 /* path points to block */
169 err
= __ext4_handle_dirty_metadata(where
, line
, handle
,
172 /* path points to leaf/index in inode body */
173 err
= ext4_mark_inode_dirty(handle
, inode
);
178 static ext4_fsblk_t
ext4_ext_find_goal(struct inode
*inode
,
179 struct ext4_ext_path
*path
,
183 int depth
= path
->p_depth
;
184 struct ext4_extent
*ex
;
187 * Try to predict block placement assuming that we are
188 * filling in a file which will eventually be
189 * non-sparse --- i.e., in the case of libbfd writing
190 * an ELF object sections out-of-order but in a way
191 * the eventually results in a contiguous object or
192 * executable file, or some database extending a table
193 * space file. However, this is actually somewhat
194 * non-ideal if we are writing a sparse file such as
195 * qemu or KVM writing a raw image file that is going
196 * to stay fairly sparse, since it will end up
197 * fragmenting the file system's free space. Maybe we
198 * should have some hueristics or some way to allow
199 * userspace to pass a hint to file system,
200 * especially if the latter case turns out to be
203 ex
= path
[depth
].p_ext
;
205 ext4_fsblk_t ext_pblk
= ext4_ext_pblock(ex
);
206 ext4_lblk_t ext_block
= le32_to_cpu(ex
->ee_block
);
208 if (block
> ext_block
)
209 return ext_pblk
+ (block
- ext_block
);
211 return ext_pblk
- (ext_block
- block
);
214 /* it looks like index is empty;
215 * try to find starting block from index itself */
216 if (path
[depth
].p_bh
)
217 return path
[depth
].p_bh
->b_blocknr
;
220 /* OK. use inode's group */
221 return ext4_inode_to_goal_block(inode
);
225 * Allocation for a meta data block
228 ext4_ext_new_meta_block(handle_t
*handle
, struct inode
*inode
,
229 struct ext4_ext_path
*path
,
230 struct ext4_extent
*ex
, int *err
, unsigned int flags
)
232 ext4_fsblk_t goal
, newblock
;
234 goal
= ext4_ext_find_goal(inode
, path
, le32_to_cpu(ex
->ee_block
));
235 newblock
= ext4_new_meta_blocks(handle
, inode
, goal
, flags
,
240 static inline int ext4_ext_space_block(struct inode
*inode
, int check
)
244 size
= (inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
245 / sizeof(struct ext4_extent
);
246 #ifdef AGGRESSIVE_TEST
247 if (!check
&& size
> 6)
253 static inline int ext4_ext_space_block_idx(struct inode
*inode
, int check
)
257 size
= (inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
258 / sizeof(struct ext4_extent_idx
);
259 #ifdef AGGRESSIVE_TEST
260 if (!check
&& size
> 5)
266 static inline int ext4_ext_space_root(struct inode
*inode
, int check
)
270 size
= sizeof(EXT4_I(inode
)->i_data
);
271 size
-= sizeof(struct ext4_extent_header
);
272 size
/= sizeof(struct ext4_extent
);
273 #ifdef AGGRESSIVE_TEST
274 if (!check
&& size
> 3)
280 static inline int ext4_ext_space_root_idx(struct inode
*inode
, int check
)
284 size
= sizeof(EXT4_I(inode
)->i_data
);
285 size
-= sizeof(struct ext4_extent_header
);
286 size
/= sizeof(struct ext4_extent_idx
);
287 #ifdef AGGRESSIVE_TEST
288 if (!check
&& size
> 4)
295 ext4_force_split_extent_at(handle_t
*handle
, struct inode
*inode
,
296 struct ext4_ext_path
**ppath
, ext4_lblk_t lblk
,
299 struct ext4_ext_path
*path
= *ppath
;
300 int unwritten
= ext4_ext_is_unwritten(path
[path
->p_depth
].p_ext
);
302 return ext4_split_extent_at(handle
, inode
, ppath
, lblk
, unwritten
?
303 EXT4_EXT_MARK_UNWRIT1
|EXT4_EXT_MARK_UNWRIT2
: 0,
304 EXT4_EX_NOCACHE
| EXT4_GET_BLOCKS_PRE_IO
|
305 (nofail
? EXT4_GET_BLOCKS_METADATA_NOFAIL
:0));
309 * Calculate the number of metadata blocks needed
310 * to allocate @blocks
311 * Worse case is one block per extent
313 int ext4_ext_calc_metadata_amount(struct inode
*inode
, ext4_lblk_t lblock
)
315 struct ext4_inode_info
*ei
= EXT4_I(inode
);
318 idxs
= ((inode
->i_sb
->s_blocksize
- sizeof(struct ext4_extent_header
))
319 / sizeof(struct ext4_extent_idx
));
322 * If the new delayed allocation block is contiguous with the
323 * previous da block, it can share index blocks with the
324 * previous block, so we only need to allocate a new index
325 * block every idxs leaf blocks. At ldxs**2 blocks, we need
326 * an additional index block, and at ldxs**3 blocks, yet
327 * another index blocks.
329 if (ei
->i_da_metadata_calc_len
&&
330 ei
->i_da_metadata_calc_last_lblock
+1 == lblock
) {
333 if ((ei
->i_da_metadata_calc_len
% idxs
) == 0)
335 if ((ei
->i_da_metadata_calc_len
% (idxs
*idxs
)) == 0)
337 if ((ei
->i_da_metadata_calc_len
% (idxs
*idxs
*idxs
)) == 0) {
339 ei
->i_da_metadata_calc_len
= 0;
341 ei
->i_da_metadata_calc_len
++;
342 ei
->i_da_metadata_calc_last_lblock
++;
347 * In the worst case we need a new set of index blocks at
348 * every level of the inode's extent tree.
350 ei
->i_da_metadata_calc_len
= 1;
351 ei
->i_da_metadata_calc_last_lblock
= lblock
;
352 return ext_depth(inode
) + 1;
356 ext4_ext_max_entries(struct inode
*inode
, int depth
)
360 if (depth
== ext_depth(inode
)) {
362 max
= ext4_ext_space_root(inode
, 1);
364 max
= ext4_ext_space_root_idx(inode
, 1);
367 max
= ext4_ext_space_block(inode
, 1);
369 max
= ext4_ext_space_block_idx(inode
, 1);
375 static int ext4_valid_extent(struct inode
*inode
, struct ext4_extent
*ext
)
377 ext4_fsblk_t block
= ext4_ext_pblock(ext
);
378 int len
= ext4_ext_get_actual_len(ext
);
379 ext4_lblk_t lblock
= le32_to_cpu(ext
->ee_block
);
380 ext4_lblk_t last
= lblock
+ len
- 1;
384 return ext4_data_block_valid(EXT4_SB(inode
->i_sb
), block
, len
);
387 static int ext4_valid_extent_idx(struct inode
*inode
,
388 struct ext4_extent_idx
*ext_idx
)
390 ext4_fsblk_t block
= ext4_idx_pblock(ext_idx
);
392 return ext4_data_block_valid(EXT4_SB(inode
->i_sb
), block
, 1);
395 static int ext4_valid_extent_entries(struct inode
*inode
,
396 struct ext4_extent_header
*eh
,
399 unsigned short entries
;
400 if (eh
->eh_entries
== 0)
403 entries
= le16_to_cpu(eh
->eh_entries
);
407 struct ext4_extent
*ext
= EXT_FIRST_EXTENT(eh
);
408 struct ext4_super_block
*es
= EXT4_SB(inode
->i_sb
)->s_es
;
409 ext4_fsblk_t pblock
= 0;
410 ext4_lblk_t lblock
= 0;
411 ext4_lblk_t prev
= 0;
414 if (!ext4_valid_extent(inode
, ext
))
417 /* Check for overlapping extents */
418 lblock
= le32_to_cpu(ext
->ee_block
);
419 len
= ext4_ext_get_actual_len(ext
);
420 if ((lblock
<= prev
) && prev
) {
421 pblock
= ext4_ext_pblock(ext
);
422 es
->s_last_error_block
= cpu_to_le64(pblock
);
427 prev
= lblock
+ len
- 1;
430 struct ext4_extent_idx
*ext_idx
= EXT_FIRST_INDEX(eh
);
432 if (!ext4_valid_extent_idx(inode
, ext_idx
))
441 static int __ext4_ext_check(const char *function
, unsigned int line
,
442 struct inode
*inode
, struct ext4_extent_header
*eh
,
443 int depth
, ext4_fsblk_t pblk
)
445 const char *error_msg
;
448 if (unlikely(eh
->eh_magic
!= EXT4_EXT_MAGIC
)) {
449 error_msg
= "invalid magic";
452 if (unlikely(le16_to_cpu(eh
->eh_depth
) != depth
)) {
453 error_msg
= "unexpected eh_depth";
456 if (unlikely(eh
->eh_max
== 0)) {
457 error_msg
= "invalid eh_max";
460 max
= ext4_ext_max_entries(inode
, depth
);
461 if (unlikely(le16_to_cpu(eh
->eh_max
) > max
)) {
462 error_msg
= "too large eh_max";
465 if (unlikely(le16_to_cpu(eh
->eh_entries
) > le16_to_cpu(eh
->eh_max
))) {
466 error_msg
= "invalid eh_entries";
469 if (!ext4_valid_extent_entries(inode
, eh
, depth
)) {
470 error_msg
= "invalid extent entries";
473 /* Verify checksum on non-root extent tree nodes */
474 if (ext_depth(inode
) != depth
&&
475 !ext4_extent_block_csum_verify(inode
, eh
)) {
476 error_msg
= "extent tree corrupted";
482 ext4_error_inode(inode
, function
, line
, 0,
483 "pblk %llu bad header/extent: %s - magic %x, "
484 "entries %u, max %u(%u), depth %u(%u)",
485 (unsigned long long) pblk
, error_msg
,
486 le16_to_cpu(eh
->eh_magic
),
487 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
),
488 max
, le16_to_cpu(eh
->eh_depth
), depth
);
492 #define ext4_ext_check(inode, eh, depth, pblk) \
493 __ext4_ext_check(__func__, __LINE__, (inode), (eh), (depth), (pblk))
495 int ext4_ext_check_inode(struct inode
*inode
)
497 return ext4_ext_check(inode
, ext_inode_hdr(inode
), ext_depth(inode
), 0);
500 static struct buffer_head
*
501 __read_extent_tree_block(const char *function
, unsigned int line
,
502 struct inode
*inode
, ext4_fsblk_t pblk
, int depth
,
505 struct buffer_head
*bh
;
508 bh
= sb_getblk(inode
->i_sb
, pblk
);
510 return ERR_PTR(-ENOMEM
);
512 if (!bh_uptodate_or_lock(bh
)) {
513 trace_ext4_ext_load_extent(inode
, pblk
, _RET_IP_
);
514 err
= bh_submit_read(bh
);
518 if (buffer_verified(bh
) && !(flags
& EXT4_EX_FORCE_CACHE
))
520 err
= __ext4_ext_check(function
, line
, inode
,
521 ext_block_hdr(bh
), depth
, pblk
);
524 set_buffer_verified(bh
);
526 * If this is a leaf block, cache all of its entries
528 if (!(flags
& EXT4_EX_NOCACHE
) && depth
== 0) {
529 struct ext4_extent_header
*eh
= ext_block_hdr(bh
);
530 struct ext4_extent
*ex
= EXT_FIRST_EXTENT(eh
);
531 ext4_lblk_t prev
= 0;
534 for (i
= le16_to_cpu(eh
->eh_entries
); i
> 0; i
--, ex
++) {
535 unsigned int status
= EXTENT_STATUS_WRITTEN
;
536 ext4_lblk_t lblk
= le32_to_cpu(ex
->ee_block
);
537 int len
= ext4_ext_get_actual_len(ex
);
539 if (prev
&& (prev
!= lblk
))
540 ext4_es_cache_extent(inode
, prev
,
544 if (ext4_ext_is_unwritten(ex
))
545 status
= EXTENT_STATUS_UNWRITTEN
;
546 ext4_es_cache_extent(inode
, lblk
, len
,
547 ext4_ext_pblock(ex
), status
);
558 #define read_extent_tree_block(inode, pblk, depth, flags) \
559 __read_extent_tree_block(__func__, __LINE__, (inode), (pblk), \
563 * This function is called to cache a file's extent information in the
566 int ext4_ext_precache(struct inode
*inode
)
568 struct ext4_inode_info
*ei
= EXT4_I(inode
);
569 struct ext4_ext_path
*path
= NULL
;
570 struct buffer_head
*bh
;
571 int i
= 0, depth
, ret
= 0;
573 if (!ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
574 return 0; /* not an extent-mapped inode */
576 down_read(&ei
->i_data_sem
);
577 depth
= ext_depth(inode
);
579 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 1),
582 up_read(&ei
->i_data_sem
);
586 /* Don't cache anything if there are no external extent blocks */
589 path
[0].p_hdr
= ext_inode_hdr(inode
);
590 ret
= ext4_ext_check(inode
, path
[0].p_hdr
, depth
, 0);
593 path
[0].p_idx
= EXT_FIRST_INDEX(path
[0].p_hdr
);
596 * If this is a leaf block or we've reached the end of
597 * the index block, go up
600 path
[i
].p_idx
> EXT_LAST_INDEX(path
[i
].p_hdr
)) {
601 brelse(path
[i
].p_bh
);
606 bh
= read_extent_tree_block(inode
,
607 ext4_idx_pblock(path
[i
].p_idx
++),
609 EXT4_EX_FORCE_CACHE
);
616 path
[i
].p_hdr
= ext_block_hdr(bh
);
617 path
[i
].p_idx
= EXT_FIRST_INDEX(path
[i
].p_hdr
);
619 ext4_set_inode_state(inode
, EXT4_STATE_EXT_PRECACHED
);
621 up_read(&ei
->i_data_sem
);
622 ext4_ext_drop_refs(path
);
628 static void ext4_ext_show_path(struct inode
*inode
, struct ext4_ext_path
*path
)
630 int k
, l
= path
->p_depth
;
633 for (k
= 0; k
<= l
; k
++, path
++) {
635 ext_debug(" %d->%llu", le32_to_cpu(path
->p_idx
->ei_block
),
636 ext4_idx_pblock(path
->p_idx
));
637 } else if (path
->p_ext
) {
638 ext_debug(" %d:[%d]%d:%llu ",
639 le32_to_cpu(path
->p_ext
->ee_block
),
640 ext4_ext_is_unwritten(path
->p_ext
),
641 ext4_ext_get_actual_len(path
->p_ext
),
642 ext4_ext_pblock(path
->p_ext
));
649 static void ext4_ext_show_leaf(struct inode
*inode
, struct ext4_ext_path
*path
)
651 int depth
= ext_depth(inode
);
652 struct ext4_extent_header
*eh
;
653 struct ext4_extent
*ex
;
659 eh
= path
[depth
].p_hdr
;
660 ex
= EXT_FIRST_EXTENT(eh
);
662 ext_debug("Displaying leaf extents for inode %lu\n", inode
->i_ino
);
664 for (i
= 0; i
< le16_to_cpu(eh
->eh_entries
); i
++, ex
++) {
665 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex
->ee_block
),
666 ext4_ext_is_unwritten(ex
),
667 ext4_ext_get_actual_len(ex
), ext4_ext_pblock(ex
));
672 static void ext4_ext_show_move(struct inode
*inode
, struct ext4_ext_path
*path
,
673 ext4_fsblk_t newblock
, int level
)
675 int depth
= ext_depth(inode
);
676 struct ext4_extent
*ex
;
678 if (depth
!= level
) {
679 struct ext4_extent_idx
*idx
;
680 idx
= path
[level
].p_idx
;
681 while (idx
<= EXT_MAX_INDEX(path
[level
].p_hdr
)) {
682 ext_debug("%d: move %d:%llu in new index %llu\n", level
,
683 le32_to_cpu(idx
->ei_block
),
684 ext4_idx_pblock(idx
),
692 ex
= path
[depth
].p_ext
;
693 while (ex
<= EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
694 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
695 le32_to_cpu(ex
->ee_block
),
697 ext4_ext_is_unwritten(ex
),
698 ext4_ext_get_actual_len(ex
),
705 #define ext4_ext_show_path(inode, path)
706 #define ext4_ext_show_leaf(inode, path)
707 #define ext4_ext_show_move(inode, path, newblock, level)
710 void ext4_ext_drop_refs(struct ext4_ext_path
*path
)
716 depth
= path
->p_depth
;
717 for (i
= 0; i
<= depth
; i
++, path
++)
725 * ext4_ext_binsearch_idx:
726 * binary search for the closest index of the given block
727 * the header must be checked before calling this
730 ext4_ext_binsearch_idx(struct inode
*inode
,
731 struct ext4_ext_path
*path
, ext4_lblk_t block
)
733 struct ext4_extent_header
*eh
= path
->p_hdr
;
734 struct ext4_extent_idx
*r
, *l
, *m
;
737 ext_debug("binsearch for %u(idx): ", block
);
739 l
= EXT_FIRST_INDEX(eh
) + 1;
740 r
= EXT_LAST_INDEX(eh
);
743 if (block
< le32_to_cpu(m
->ei_block
))
747 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ei_block
),
748 m
, le32_to_cpu(m
->ei_block
),
749 r
, le32_to_cpu(r
->ei_block
));
753 ext_debug(" -> %u->%lld ", le32_to_cpu(path
->p_idx
->ei_block
),
754 ext4_idx_pblock(path
->p_idx
));
756 #ifdef CHECK_BINSEARCH
758 struct ext4_extent_idx
*chix
, *ix
;
761 chix
= ix
= EXT_FIRST_INDEX(eh
);
762 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ix
++) {
764 le32_to_cpu(ix
->ei_block
) <= le32_to_cpu(ix
[-1].ei_block
)) {
765 printk(KERN_DEBUG
"k=%d, ix=0x%p, "
767 ix
, EXT_FIRST_INDEX(eh
));
768 printk(KERN_DEBUG
"%u <= %u\n",
769 le32_to_cpu(ix
->ei_block
),
770 le32_to_cpu(ix
[-1].ei_block
));
772 BUG_ON(k
&& le32_to_cpu(ix
->ei_block
)
773 <= le32_to_cpu(ix
[-1].ei_block
));
774 if (block
< le32_to_cpu(ix
->ei_block
))
778 BUG_ON(chix
!= path
->p_idx
);
785 * ext4_ext_binsearch:
786 * binary search for closest extent of the given block
787 * the header must be checked before calling this
790 ext4_ext_binsearch(struct inode
*inode
,
791 struct ext4_ext_path
*path
, ext4_lblk_t block
)
793 struct ext4_extent_header
*eh
= path
->p_hdr
;
794 struct ext4_extent
*r
, *l
, *m
;
796 if (eh
->eh_entries
== 0) {
798 * this leaf is empty:
799 * we get such a leaf in split/add case
804 ext_debug("binsearch for %u: ", block
);
806 l
= EXT_FIRST_EXTENT(eh
) + 1;
807 r
= EXT_LAST_EXTENT(eh
);
811 if (block
< le32_to_cpu(m
->ee_block
))
815 ext_debug("%p(%u):%p(%u):%p(%u) ", l
, le32_to_cpu(l
->ee_block
),
816 m
, le32_to_cpu(m
->ee_block
),
817 r
, le32_to_cpu(r
->ee_block
));
821 ext_debug(" -> %d:%llu:[%d]%d ",
822 le32_to_cpu(path
->p_ext
->ee_block
),
823 ext4_ext_pblock(path
->p_ext
),
824 ext4_ext_is_unwritten(path
->p_ext
),
825 ext4_ext_get_actual_len(path
->p_ext
));
827 #ifdef CHECK_BINSEARCH
829 struct ext4_extent
*chex
, *ex
;
832 chex
= ex
= EXT_FIRST_EXTENT(eh
);
833 for (k
= 0; k
< le16_to_cpu(eh
->eh_entries
); k
++, ex
++) {
834 BUG_ON(k
&& le32_to_cpu(ex
->ee_block
)
835 <= le32_to_cpu(ex
[-1].ee_block
));
836 if (block
< le32_to_cpu(ex
->ee_block
))
840 BUG_ON(chex
!= path
->p_ext
);
846 int ext4_ext_tree_init(handle_t
*handle
, struct inode
*inode
)
848 struct ext4_extent_header
*eh
;
850 eh
= ext_inode_hdr(inode
);
853 eh
->eh_magic
= EXT4_EXT_MAGIC
;
854 eh
->eh_max
= cpu_to_le16(ext4_ext_space_root(inode
, 0));
855 ext4_mark_inode_dirty(handle
, inode
);
859 struct ext4_ext_path
*
860 ext4_ext_find_extent(struct inode
*inode
, ext4_lblk_t block
,
861 struct ext4_ext_path
**orig_path
, int flags
)
863 struct ext4_extent_header
*eh
;
864 struct buffer_head
*bh
;
865 struct ext4_ext_path
*path
= orig_path
? *orig_path
: NULL
;
866 short int depth
, i
, ppos
= 0;
869 eh
= ext_inode_hdr(inode
);
870 depth
= ext_depth(inode
);
873 ext4_ext_drop_refs(path
);
874 if (depth
> path
[0].p_maxdepth
) {
876 *orig_path
= path
= NULL
;
880 /* account possible depth increase */
881 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 2),
884 return ERR_PTR(-ENOMEM
);
885 path
[0].p_maxdepth
= depth
+ 1;
891 /* walk through the tree */
893 ext_debug("depth %d: num %d, max %d\n",
894 ppos
, le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
896 ext4_ext_binsearch_idx(inode
, path
+ ppos
, block
);
897 path
[ppos
].p_block
= ext4_idx_pblock(path
[ppos
].p_idx
);
898 path
[ppos
].p_depth
= i
;
899 path
[ppos
].p_ext
= NULL
;
901 bh
= read_extent_tree_block(inode
, path
[ppos
].p_block
, --i
,
903 if (unlikely(IS_ERR(bh
))) {
908 eh
= ext_block_hdr(bh
);
910 if (unlikely(ppos
> depth
)) {
912 EXT4_ERROR_INODE(inode
,
913 "ppos %d > depth %d", ppos
, depth
);
917 path
[ppos
].p_bh
= bh
;
918 path
[ppos
].p_hdr
= eh
;
921 path
[ppos
].p_depth
= i
;
922 path
[ppos
].p_ext
= NULL
;
923 path
[ppos
].p_idx
= NULL
;
926 ext4_ext_binsearch(inode
, path
+ ppos
, block
);
927 /* if not an empty leaf */
928 if (path
[ppos
].p_ext
)
929 path
[ppos
].p_block
= ext4_ext_pblock(path
[ppos
].p_ext
);
931 ext4_ext_show_path(inode
, path
);
936 ext4_ext_drop_refs(path
);
944 * ext4_ext_insert_index:
945 * insert new index [@logical;@ptr] into the block at @curp;
946 * check where to insert: before @curp or after @curp
948 static int ext4_ext_insert_index(handle_t
*handle
, struct inode
*inode
,
949 struct ext4_ext_path
*curp
,
950 int logical
, ext4_fsblk_t ptr
)
952 struct ext4_extent_idx
*ix
;
955 err
= ext4_ext_get_access(handle
, inode
, curp
);
959 if (unlikely(logical
== le32_to_cpu(curp
->p_idx
->ei_block
))) {
960 EXT4_ERROR_INODE(inode
,
961 "logical %d == ei_block %d!",
962 logical
, le32_to_cpu(curp
->p_idx
->ei_block
));
966 if (unlikely(le16_to_cpu(curp
->p_hdr
->eh_entries
)
967 >= le16_to_cpu(curp
->p_hdr
->eh_max
))) {
968 EXT4_ERROR_INODE(inode
,
969 "eh_entries %d >= eh_max %d!",
970 le16_to_cpu(curp
->p_hdr
->eh_entries
),
971 le16_to_cpu(curp
->p_hdr
->eh_max
));
975 if (logical
> le32_to_cpu(curp
->p_idx
->ei_block
)) {
977 ext_debug("insert new index %d after: %llu\n", logical
, ptr
);
978 ix
= curp
->p_idx
+ 1;
981 ext_debug("insert new index %d before: %llu\n", logical
, ptr
);
985 len
= EXT_LAST_INDEX(curp
->p_hdr
) - ix
+ 1;
988 ext_debug("insert new index %d: "
989 "move %d indices from 0x%p to 0x%p\n",
990 logical
, len
, ix
, ix
+ 1);
991 memmove(ix
+ 1, ix
, len
* sizeof(struct ext4_extent_idx
));
994 if (unlikely(ix
> EXT_MAX_INDEX(curp
->p_hdr
))) {
995 EXT4_ERROR_INODE(inode
, "ix > EXT_MAX_INDEX!");
999 ix
->ei_block
= cpu_to_le32(logical
);
1000 ext4_idx_store_pblock(ix
, ptr
);
1001 le16_add_cpu(&curp
->p_hdr
->eh_entries
, 1);
1003 if (unlikely(ix
> EXT_LAST_INDEX(curp
->p_hdr
))) {
1004 EXT4_ERROR_INODE(inode
, "ix > EXT_LAST_INDEX!");
1008 err
= ext4_ext_dirty(handle
, inode
, curp
);
1009 ext4_std_error(inode
->i_sb
, err
);
1016 * inserts new subtree into the path, using free index entry
1018 * - allocates all needed blocks (new leaf and all intermediate index blocks)
1019 * - makes decision where to split
1020 * - moves remaining extents and index entries (right to the split point)
1021 * into the newly allocated blocks
1022 * - initializes subtree
1024 static int ext4_ext_split(handle_t
*handle
, struct inode
*inode
,
1026 struct ext4_ext_path
*path
,
1027 struct ext4_extent
*newext
, int at
)
1029 struct buffer_head
*bh
= NULL
;
1030 int depth
= ext_depth(inode
);
1031 struct ext4_extent_header
*neh
;
1032 struct ext4_extent_idx
*fidx
;
1033 int i
= at
, k
, m
, a
;
1034 ext4_fsblk_t newblock
, oldblock
;
1036 ext4_fsblk_t
*ablocks
= NULL
; /* array of allocated blocks */
1039 /* make decision: where to split? */
1040 /* FIXME: now decision is simplest: at current extent */
1042 /* if current leaf will be split, then we should use
1043 * border from split point */
1044 if (unlikely(path
[depth
].p_ext
> EXT_MAX_EXTENT(path
[depth
].p_hdr
))) {
1045 EXT4_ERROR_INODE(inode
, "p_ext > EXT_MAX_EXTENT!");
1048 if (path
[depth
].p_ext
!= EXT_MAX_EXTENT(path
[depth
].p_hdr
)) {
1049 border
= path
[depth
].p_ext
[1].ee_block
;
1050 ext_debug("leaf will be split."
1051 " next leaf starts at %d\n",
1052 le32_to_cpu(border
));
1054 border
= newext
->ee_block
;
1055 ext_debug("leaf will be added."
1056 " next leaf starts at %d\n",
1057 le32_to_cpu(border
));
1061 * If error occurs, then we break processing
1062 * and mark filesystem read-only. index won't
1063 * be inserted and tree will be in consistent
1064 * state. Next mount will repair buffers too.
1068 * Get array to track all allocated blocks.
1069 * We need this to handle errors and free blocks
1072 ablocks
= kzalloc(sizeof(ext4_fsblk_t
) * depth
, GFP_NOFS
);
1076 /* allocate all needed blocks */
1077 ext_debug("allocate %d blocks for indexes/leaf\n", depth
- at
);
1078 for (a
= 0; a
< depth
- at
; a
++) {
1079 newblock
= ext4_ext_new_meta_block(handle
, inode
, path
,
1080 newext
, &err
, flags
);
1083 ablocks
[a
] = newblock
;
1086 /* initialize new leaf */
1087 newblock
= ablocks
[--a
];
1088 if (unlikely(newblock
== 0)) {
1089 EXT4_ERROR_INODE(inode
, "newblock == 0!");
1093 bh
= sb_getblk(inode
->i_sb
, newblock
);
1094 if (unlikely(!bh
)) {
1100 err
= ext4_journal_get_create_access(handle
, bh
);
1104 neh
= ext_block_hdr(bh
);
1105 neh
->eh_entries
= 0;
1106 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
, 0));
1107 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1110 /* move remainder of path[depth] to the new leaf */
1111 if (unlikely(path
[depth
].p_hdr
->eh_entries
!=
1112 path
[depth
].p_hdr
->eh_max
)) {
1113 EXT4_ERROR_INODE(inode
, "eh_entries %d != eh_max %d!",
1114 path
[depth
].p_hdr
->eh_entries
,
1115 path
[depth
].p_hdr
->eh_max
);
1119 /* start copy from next extent */
1120 m
= EXT_MAX_EXTENT(path
[depth
].p_hdr
) - path
[depth
].p_ext
++;
1121 ext4_ext_show_move(inode
, path
, newblock
, depth
);
1123 struct ext4_extent
*ex
;
1124 ex
= EXT_FIRST_EXTENT(neh
);
1125 memmove(ex
, path
[depth
].p_ext
, sizeof(struct ext4_extent
) * m
);
1126 le16_add_cpu(&neh
->eh_entries
, m
);
1129 ext4_extent_block_csum_set(inode
, neh
);
1130 set_buffer_uptodate(bh
);
1133 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1139 /* correct old leaf */
1141 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
1144 le16_add_cpu(&path
[depth
].p_hdr
->eh_entries
, -m
);
1145 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
1151 /* create intermediate indexes */
1153 if (unlikely(k
< 0)) {
1154 EXT4_ERROR_INODE(inode
, "k %d < 0!", k
);
1159 ext_debug("create %d intermediate indices\n", k
);
1160 /* insert new index into current index block */
1161 /* current depth stored in i var */
1164 oldblock
= newblock
;
1165 newblock
= ablocks
[--a
];
1166 bh
= sb_getblk(inode
->i_sb
, newblock
);
1167 if (unlikely(!bh
)) {
1173 err
= ext4_journal_get_create_access(handle
, bh
);
1177 neh
= ext_block_hdr(bh
);
1178 neh
->eh_entries
= cpu_to_le16(1);
1179 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1180 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
, 0));
1181 neh
->eh_depth
= cpu_to_le16(depth
- i
);
1182 fidx
= EXT_FIRST_INDEX(neh
);
1183 fidx
->ei_block
= border
;
1184 ext4_idx_store_pblock(fidx
, oldblock
);
1186 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
1187 i
, newblock
, le32_to_cpu(border
), oldblock
);
1189 /* move remainder of path[i] to the new index block */
1190 if (unlikely(EXT_MAX_INDEX(path
[i
].p_hdr
) !=
1191 EXT_LAST_INDEX(path
[i
].p_hdr
))) {
1192 EXT4_ERROR_INODE(inode
,
1193 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
1194 le32_to_cpu(path
[i
].p_ext
->ee_block
));
1198 /* start copy indexes */
1199 m
= EXT_MAX_INDEX(path
[i
].p_hdr
) - path
[i
].p_idx
++;
1200 ext_debug("cur 0x%p, last 0x%p\n", path
[i
].p_idx
,
1201 EXT_MAX_INDEX(path
[i
].p_hdr
));
1202 ext4_ext_show_move(inode
, path
, newblock
, i
);
1204 memmove(++fidx
, path
[i
].p_idx
,
1205 sizeof(struct ext4_extent_idx
) * m
);
1206 le16_add_cpu(&neh
->eh_entries
, m
);
1208 ext4_extent_block_csum_set(inode
, neh
);
1209 set_buffer_uptodate(bh
);
1212 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1218 /* correct old index */
1220 err
= ext4_ext_get_access(handle
, inode
, path
+ i
);
1223 le16_add_cpu(&path
[i
].p_hdr
->eh_entries
, -m
);
1224 err
= ext4_ext_dirty(handle
, inode
, path
+ i
);
1232 /* insert new index */
1233 err
= ext4_ext_insert_index(handle
, inode
, path
+ at
,
1234 le32_to_cpu(border
), newblock
);
1238 if (buffer_locked(bh
))
1244 /* free all allocated blocks in error case */
1245 for (i
= 0; i
< depth
; i
++) {
1248 ext4_free_blocks(handle
, inode
, NULL
, ablocks
[i
], 1,
1249 EXT4_FREE_BLOCKS_METADATA
);
1258 * ext4_ext_grow_indepth:
1259 * implements tree growing procedure:
1260 * - allocates new block
1261 * - moves top-level data (index block or leaf) into the new block
1262 * - initializes new top-level, creating index that points to the
1263 * just created block
1265 static int ext4_ext_grow_indepth(handle_t
*handle
, struct inode
*inode
,
1267 struct ext4_extent
*newext
)
1269 struct ext4_extent_header
*neh
;
1270 struct buffer_head
*bh
;
1271 ext4_fsblk_t newblock
;
1274 newblock
= ext4_ext_new_meta_block(handle
, inode
, NULL
,
1275 newext
, &err
, flags
);
1279 bh
= sb_getblk(inode
->i_sb
, newblock
);
1284 err
= ext4_journal_get_create_access(handle
, bh
);
1290 /* move top-level index/leaf into new block */
1291 memmove(bh
->b_data
, EXT4_I(inode
)->i_data
,
1292 sizeof(EXT4_I(inode
)->i_data
));
1294 /* set size of new block */
1295 neh
= ext_block_hdr(bh
);
1296 /* old root could have indexes or leaves
1297 * so calculate e_max right way */
1298 if (ext_depth(inode
))
1299 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block_idx(inode
, 0));
1301 neh
->eh_max
= cpu_to_le16(ext4_ext_space_block(inode
, 0));
1302 neh
->eh_magic
= EXT4_EXT_MAGIC
;
1303 ext4_extent_block_csum_set(inode
, neh
);
1304 set_buffer_uptodate(bh
);
1307 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
1311 /* Update top-level index: num,max,pointer */
1312 neh
= ext_inode_hdr(inode
);
1313 neh
->eh_entries
= cpu_to_le16(1);
1314 ext4_idx_store_pblock(EXT_FIRST_INDEX(neh
), newblock
);
1315 if (neh
->eh_depth
== 0) {
1316 /* Root extent block becomes index block */
1317 neh
->eh_max
= cpu_to_le16(ext4_ext_space_root_idx(inode
, 0));
1318 EXT_FIRST_INDEX(neh
)->ei_block
=
1319 EXT_FIRST_EXTENT(neh
)->ee_block
;
1321 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1322 le16_to_cpu(neh
->eh_entries
), le16_to_cpu(neh
->eh_max
),
1323 le32_to_cpu(EXT_FIRST_INDEX(neh
)->ei_block
),
1324 ext4_idx_pblock(EXT_FIRST_INDEX(neh
)));
1326 le16_add_cpu(&neh
->eh_depth
, 1);
1327 ext4_mark_inode_dirty(handle
, inode
);
1335 * ext4_ext_create_new_leaf:
1336 * finds empty index and adds new leaf.
1337 * if no free index is found, then it requests in-depth growing.
1339 static int ext4_ext_create_new_leaf(handle_t
*handle
, struct inode
*inode
,
1340 unsigned int mb_flags
,
1341 unsigned int gb_flags
,
1342 struct ext4_ext_path
**ppath
,
1343 struct ext4_extent
*newext
)
1345 struct ext4_ext_path
*path
= *ppath
;
1346 struct ext4_ext_path
*curp
;
1347 int depth
, i
, err
= 0;
1350 i
= depth
= ext_depth(inode
);
1352 /* walk up to the tree and look for free index entry */
1353 curp
= path
+ depth
;
1354 while (i
> 0 && !EXT_HAS_FREE_INDEX(curp
)) {
1359 /* we use already allocated block for index block,
1360 * so subsequent data blocks should be contiguous */
1361 if (EXT_HAS_FREE_INDEX(curp
)) {
1362 /* if we found index with free entry, then use that
1363 * entry: create all needed subtree and add new leaf */
1364 err
= ext4_ext_split(handle
, inode
, mb_flags
, path
, newext
, i
);
1369 path
= ext4_ext_find_extent(inode
,
1370 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1373 err
= PTR_ERR(path
);
1375 /* tree is full, time to grow in depth */
1376 err
= ext4_ext_grow_indepth(handle
, inode
, mb_flags
, newext
);
1381 path
= ext4_ext_find_extent(inode
,
1382 (ext4_lblk_t
)le32_to_cpu(newext
->ee_block
),
1385 err
= PTR_ERR(path
);
1390 * only first (depth 0 -> 1) produces free space;
1391 * in all other cases we have to split the grown tree
1393 depth
= ext_depth(inode
);
1394 if (path
[depth
].p_hdr
->eh_entries
== path
[depth
].p_hdr
->eh_max
) {
1395 /* now we need to split */
1405 * search the closest allocated block to the left for *logical
1406 * and returns it at @logical + it's physical address at @phys
1407 * if *logical is the smallest allocated block, the function
1408 * returns 0 at @phys
1409 * return value contains 0 (success) or error code
1411 static int ext4_ext_search_left(struct inode
*inode
,
1412 struct ext4_ext_path
*path
,
1413 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
)
1415 struct ext4_extent_idx
*ix
;
1416 struct ext4_extent
*ex
;
1419 if (unlikely(path
== NULL
)) {
1420 EXT4_ERROR_INODE(inode
, "path == NULL *logical %d!", *logical
);
1423 depth
= path
->p_depth
;
1426 if (depth
== 0 && path
->p_ext
== NULL
)
1429 /* usually extent in the path covers blocks smaller
1430 * then *logical, but it can be that extent is the
1431 * first one in the file */
1433 ex
= path
[depth
].p_ext
;
1434 ee_len
= ext4_ext_get_actual_len(ex
);
1435 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1436 if (unlikely(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
)) {
1437 EXT4_ERROR_INODE(inode
,
1438 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
1439 *logical
, le32_to_cpu(ex
->ee_block
));
1442 while (--depth
>= 0) {
1443 ix
= path
[depth
].p_idx
;
1444 if (unlikely(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
))) {
1445 EXT4_ERROR_INODE(inode
,
1446 "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
1447 ix
!= NULL
? le32_to_cpu(ix
->ei_block
) : 0,
1448 EXT_FIRST_INDEX(path
[depth
].p_hdr
) != NULL
?
1449 le32_to_cpu(EXT_FIRST_INDEX(path
[depth
].p_hdr
)->ei_block
) : 0,
1457 if (unlikely(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
))) {
1458 EXT4_ERROR_INODE(inode
,
1459 "logical %d < ee_block %d + ee_len %d!",
1460 *logical
, le32_to_cpu(ex
->ee_block
), ee_len
);
1464 *logical
= le32_to_cpu(ex
->ee_block
) + ee_len
- 1;
1465 *phys
= ext4_ext_pblock(ex
) + ee_len
- 1;
1470 * search the closest allocated block to the right for *logical
1471 * and returns it at @logical + it's physical address at @phys
1472 * if *logical is the largest allocated block, the function
1473 * returns 0 at @phys
1474 * return value contains 0 (success) or error code
1476 static int ext4_ext_search_right(struct inode
*inode
,
1477 struct ext4_ext_path
*path
,
1478 ext4_lblk_t
*logical
, ext4_fsblk_t
*phys
,
1479 struct ext4_extent
**ret_ex
)
1481 struct buffer_head
*bh
= NULL
;
1482 struct ext4_extent_header
*eh
;
1483 struct ext4_extent_idx
*ix
;
1484 struct ext4_extent
*ex
;
1486 int depth
; /* Note, NOT eh_depth; depth from top of tree */
1489 if (unlikely(path
== NULL
)) {
1490 EXT4_ERROR_INODE(inode
, "path == NULL *logical %d!", *logical
);
1493 depth
= path
->p_depth
;
1496 if (depth
== 0 && path
->p_ext
== NULL
)
1499 /* usually extent in the path covers blocks smaller
1500 * then *logical, but it can be that extent is the
1501 * first one in the file */
1503 ex
= path
[depth
].p_ext
;
1504 ee_len
= ext4_ext_get_actual_len(ex
);
1505 if (*logical
< le32_to_cpu(ex
->ee_block
)) {
1506 if (unlikely(EXT_FIRST_EXTENT(path
[depth
].p_hdr
) != ex
)) {
1507 EXT4_ERROR_INODE(inode
,
1508 "first_extent(path[%d].p_hdr) != ex",
1512 while (--depth
>= 0) {
1513 ix
= path
[depth
].p_idx
;
1514 if (unlikely(ix
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
))) {
1515 EXT4_ERROR_INODE(inode
,
1516 "ix != EXT_FIRST_INDEX *logical %d!",
1524 if (unlikely(*logical
< (le32_to_cpu(ex
->ee_block
) + ee_len
))) {
1525 EXT4_ERROR_INODE(inode
,
1526 "logical %d < ee_block %d + ee_len %d!",
1527 *logical
, le32_to_cpu(ex
->ee_block
), ee_len
);
1531 if (ex
!= EXT_LAST_EXTENT(path
[depth
].p_hdr
)) {
1532 /* next allocated block in this leaf */
1537 /* go up and search for index to the right */
1538 while (--depth
>= 0) {
1539 ix
= path
[depth
].p_idx
;
1540 if (ix
!= EXT_LAST_INDEX(path
[depth
].p_hdr
))
1544 /* we've gone up to the root and found no index to the right */
1548 /* we've found index to the right, let's
1549 * follow it and find the closest allocated
1550 * block to the right */
1552 block
= ext4_idx_pblock(ix
);
1553 while (++depth
< path
->p_depth
) {
1554 /* subtract from p_depth to get proper eh_depth */
1555 bh
= read_extent_tree_block(inode
, block
,
1556 path
->p_depth
- depth
, 0);
1559 eh
= ext_block_hdr(bh
);
1560 ix
= EXT_FIRST_INDEX(eh
);
1561 block
= ext4_idx_pblock(ix
);
1565 bh
= read_extent_tree_block(inode
, block
, path
->p_depth
- depth
, 0);
1568 eh
= ext_block_hdr(bh
);
1569 ex
= EXT_FIRST_EXTENT(eh
);
1571 *logical
= le32_to_cpu(ex
->ee_block
);
1572 *phys
= ext4_ext_pblock(ex
);
1580 * ext4_ext_next_allocated_block:
1581 * returns allocated block in subsequent extent or EXT_MAX_BLOCKS.
1582 * NOTE: it considers block number from index entry as
1583 * allocated block. Thus, index entries have to be consistent
1587 ext4_ext_next_allocated_block(struct ext4_ext_path
*path
)
1591 BUG_ON(path
== NULL
);
1592 depth
= path
->p_depth
;
1594 if (depth
== 0 && path
->p_ext
== NULL
)
1595 return EXT_MAX_BLOCKS
;
1597 while (depth
>= 0) {
1598 if (depth
== path
->p_depth
) {
1600 if (path
[depth
].p_ext
&&
1601 path
[depth
].p_ext
!=
1602 EXT_LAST_EXTENT(path
[depth
].p_hdr
))
1603 return le32_to_cpu(path
[depth
].p_ext
[1].ee_block
);
1606 if (path
[depth
].p_idx
!=
1607 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1608 return le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1613 return EXT_MAX_BLOCKS
;
1617 * ext4_ext_next_leaf_block:
1618 * returns first allocated block from next leaf or EXT_MAX_BLOCKS
1620 static ext4_lblk_t
ext4_ext_next_leaf_block(struct ext4_ext_path
*path
)
1624 BUG_ON(path
== NULL
);
1625 depth
= path
->p_depth
;
1627 /* zero-tree has no leaf blocks at all */
1629 return EXT_MAX_BLOCKS
;
1631 /* go to index block */
1634 while (depth
>= 0) {
1635 if (path
[depth
].p_idx
!=
1636 EXT_LAST_INDEX(path
[depth
].p_hdr
))
1637 return (ext4_lblk_t
)
1638 le32_to_cpu(path
[depth
].p_idx
[1].ei_block
);
1642 return EXT_MAX_BLOCKS
;
1646 * ext4_ext_correct_indexes:
1647 * if leaf gets modified and modified extent is first in the leaf,
1648 * then we have to correct all indexes above.
1649 * TODO: do we need to correct tree in all cases?
1651 static int ext4_ext_correct_indexes(handle_t
*handle
, struct inode
*inode
,
1652 struct ext4_ext_path
*path
)
1654 struct ext4_extent_header
*eh
;
1655 int depth
= ext_depth(inode
);
1656 struct ext4_extent
*ex
;
1660 eh
= path
[depth
].p_hdr
;
1661 ex
= path
[depth
].p_ext
;
1663 if (unlikely(ex
== NULL
|| eh
== NULL
)) {
1664 EXT4_ERROR_INODE(inode
,
1665 "ex %p == NULL or eh %p == NULL", ex
, eh
);
1670 /* there is no tree at all */
1674 if (ex
!= EXT_FIRST_EXTENT(eh
)) {
1675 /* we correct tree if first leaf got modified only */
1680 * TODO: we need correction if border is smaller than current one
1683 border
= path
[depth
].p_ext
->ee_block
;
1684 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1687 path
[k
].p_idx
->ei_block
= border
;
1688 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1693 /* change all left-side indexes */
1694 if (path
[k
+1].p_idx
!= EXT_FIRST_INDEX(path
[k
+1].p_hdr
))
1696 err
= ext4_ext_get_access(handle
, inode
, path
+ k
);
1699 path
[k
].p_idx
->ei_block
= border
;
1700 err
= ext4_ext_dirty(handle
, inode
, path
+ k
);
1709 ext4_can_extents_be_merged(struct inode
*inode
, struct ext4_extent
*ex1
,
1710 struct ext4_extent
*ex2
)
1712 unsigned short ext1_ee_len
, ext2_ee_len
;
1715 * Make sure that both extents are initialized. We don't merge
1716 * unwritten extents so that we can be sure that end_io code has
1717 * the extent that was written properly split out and conversion to
1718 * initialized is trivial.
1720 if (ext4_ext_is_unwritten(ex1
) != ext4_ext_is_unwritten(ex2
))
1723 ext1_ee_len
= ext4_ext_get_actual_len(ex1
);
1724 ext2_ee_len
= ext4_ext_get_actual_len(ex2
);
1726 if (le32_to_cpu(ex1
->ee_block
) + ext1_ee_len
!=
1727 le32_to_cpu(ex2
->ee_block
))
1731 * To allow future support for preallocated extents to be added
1732 * as an RO_COMPAT feature, refuse to merge to extents if
1733 * this can result in the top bit of ee_len being set.
1735 if (ext1_ee_len
+ ext2_ee_len
> EXT_INIT_MAX_LEN
)
1737 if (ext4_ext_is_unwritten(ex1
) &&
1738 (ext4_test_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
) ||
1739 atomic_read(&EXT4_I(inode
)->i_unwritten
) ||
1740 (ext1_ee_len
+ ext2_ee_len
> EXT_UNWRITTEN_MAX_LEN
)))
1742 #ifdef AGGRESSIVE_TEST
1743 if (ext1_ee_len
>= 4)
1747 if (ext4_ext_pblock(ex1
) + ext1_ee_len
== ext4_ext_pblock(ex2
))
1753 * This function tries to merge the "ex" extent to the next extent in the tree.
1754 * It always tries to merge towards right. If you want to merge towards
1755 * left, pass "ex - 1" as argument instead of "ex".
1756 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1757 * 1 if they got merged.
1759 static int ext4_ext_try_to_merge_right(struct inode
*inode
,
1760 struct ext4_ext_path
*path
,
1761 struct ext4_extent
*ex
)
1763 struct ext4_extent_header
*eh
;
1764 unsigned int depth
, len
;
1765 int merge_done
= 0, unwritten
;
1767 depth
= ext_depth(inode
);
1768 BUG_ON(path
[depth
].p_hdr
== NULL
);
1769 eh
= path
[depth
].p_hdr
;
1771 while (ex
< EXT_LAST_EXTENT(eh
)) {
1772 if (!ext4_can_extents_be_merged(inode
, ex
, ex
+ 1))
1774 /* merge with next extent! */
1775 unwritten
= ext4_ext_is_unwritten(ex
);
1776 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1777 + ext4_ext_get_actual_len(ex
+ 1));
1779 ext4_ext_mark_unwritten(ex
);
1781 if (ex
+ 1 < EXT_LAST_EXTENT(eh
)) {
1782 len
= (EXT_LAST_EXTENT(eh
) - ex
- 1)
1783 * sizeof(struct ext4_extent
);
1784 memmove(ex
+ 1, ex
+ 2, len
);
1786 le16_add_cpu(&eh
->eh_entries
, -1);
1788 WARN_ON(eh
->eh_entries
== 0);
1789 if (!eh
->eh_entries
)
1790 EXT4_ERROR_INODE(inode
, "eh->eh_entries = 0!");
1797 * This function does a very simple check to see if we can collapse
1798 * an extent tree with a single extent tree leaf block into the inode.
1800 static void ext4_ext_try_to_merge_up(handle_t
*handle
,
1801 struct inode
*inode
,
1802 struct ext4_ext_path
*path
)
1805 unsigned max_root
= ext4_ext_space_root(inode
, 0);
1808 if ((path
[0].p_depth
!= 1) ||
1809 (le16_to_cpu(path
[0].p_hdr
->eh_entries
) != 1) ||
1810 (le16_to_cpu(path
[1].p_hdr
->eh_entries
) > max_root
))
1814 * We need to modify the block allocation bitmap and the block
1815 * group descriptor to release the extent tree block. If we
1816 * can't get the journal credits, give up.
1818 if (ext4_journal_extend(handle
, 2))
1822 * Copy the extent data up to the inode
1824 blk
= ext4_idx_pblock(path
[0].p_idx
);
1825 s
= le16_to_cpu(path
[1].p_hdr
->eh_entries
) *
1826 sizeof(struct ext4_extent_idx
);
1827 s
+= sizeof(struct ext4_extent_header
);
1829 path
[1].p_maxdepth
= path
[0].p_maxdepth
;
1830 memcpy(path
[0].p_hdr
, path
[1].p_hdr
, s
);
1831 path
[0].p_depth
= 0;
1832 path
[0].p_ext
= EXT_FIRST_EXTENT(path
[0].p_hdr
) +
1833 (path
[1].p_ext
- EXT_FIRST_EXTENT(path
[1].p_hdr
));
1834 path
[0].p_hdr
->eh_max
= cpu_to_le16(max_root
);
1836 brelse(path
[1].p_bh
);
1837 ext4_free_blocks(handle
, inode
, NULL
, blk
, 1,
1838 EXT4_FREE_BLOCKS_METADATA
| EXT4_FREE_BLOCKS_FORGET
);
1842 * This function tries to merge the @ex extent to neighbours in the tree.
1843 * return 1 if merge left else 0.
1845 static void ext4_ext_try_to_merge(handle_t
*handle
,
1846 struct inode
*inode
,
1847 struct ext4_ext_path
*path
,
1848 struct ext4_extent
*ex
) {
1849 struct ext4_extent_header
*eh
;
1853 depth
= ext_depth(inode
);
1854 BUG_ON(path
[depth
].p_hdr
== NULL
);
1855 eh
= path
[depth
].p_hdr
;
1857 if (ex
> EXT_FIRST_EXTENT(eh
))
1858 merge_done
= ext4_ext_try_to_merge_right(inode
, path
, ex
- 1);
1861 (void) ext4_ext_try_to_merge_right(inode
, path
, ex
);
1863 ext4_ext_try_to_merge_up(handle
, inode
, path
);
1867 * check if a portion of the "newext" extent overlaps with an
1870 * If there is an overlap discovered, it updates the length of the newext
1871 * such that there will be no overlap, and then returns 1.
1872 * If there is no overlap found, it returns 0.
1874 static unsigned int ext4_ext_check_overlap(struct ext4_sb_info
*sbi
,
1875 struct inode
*inode
,
1876 struct ext4_extent
*newext
,
1877 struct ext4_ext_path
*path
)
1880 unsigned int depth
, len1
;
1881 unsigned int ret
= 0;
1883 b1
= le32_to_cpu(newext
->ee_block
);
1884 len1
= ext4_ext_get_actual_len(newext
);
1885 depth
= ext_depth(inode
);
1886 if (!path
[depth
].p_ext
)
1888 b2
= EXT4_LBLK_CMASK(sbi
, le32_to_cpu(path
[depth
].p_ext
->ee_block
));
1891 * get the next allocated block if the extent in the path
1892 * is before the requested block(s)
1895 b2
= ext4_ext_next_allocated_block(path
);
1896 if (b2
== EXT_MAX_BLOCKS
)
1898 b2
= EXT4_LBLK_CMASK(sbi
, b2
);
1901 /* check for wrap through zero on extent logical start block*/
1902 if (b1
+ len1
< b1
) {
1903 len1
= EXT_MAX_BLOCKS
- b1
;
1904 newext
->ee_len
= cpu_to_le16(len1
);
1908 /* check for overlap */
1909 if (b1
+ len1
> b2
) {
1910 newext
->ee_len
= cpu_to_le16(b2
- b1
);
1918 * ext4_ext_insert_extent:
1919 * tries to merge requsted extent into the existing extent or
1920 * inserts requested extent as new one into the tree,
1921 * creating new leaf in the no-space case.
1923 int ext4_ext_insert_extent(handle_t
*handle
, struct inode
*inode
,
1924 struct ext4_ext_path
**ppath
,
1925 struct ext4_extent
*newext
, int gb_flags
)
1927 struct ext4_ext_path
*path
= *ppath
;
1928 struct ext4_extent_header
*eh
;
1929 struct ext4_extent
*ex
, *fex
;
1930 struct ext4_extent
*nearex
; /* nearest extent */
1931 struct ext4_ext_path
*npath
= NULL
;
1932 int depth
, len
, err
;
1934 int mb_flags
= 0, unwritten
;
1936 if (unlikely(ext4_ext_get_actual_len(newext
) == 0)) {
1937 EXT4_ERROR_INODE(inode
, "ext4_ext_get_actual_len(newext) == 0");
1940 depth
= ext_depth(inode
);
1941 ex
= path
[depth
].p_ext
;
1942 eh
= path
[depth
].p_hdr
;
1943 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
1944 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
1948 /* try to insert block into found extent and return */
1949 if (ex
&& !(gb_flags
& EXT4_GET_BLOCKS_PRE_IO
)) {
1952 * Try to see whether we should rather test the extent on
1953 * right from ex, or from the left of ex. This is because
1954 * ext4_ext_find_extent() can return either extent on the
1955 * left, or on the right from the searched position. This
1956 * will make merging more effective.
1958 if (ex
< EXT_LAST_EXTENT(eh
) &&
1959 (le32_to_cpu(ex
->ee_block
) +
1960 ext4_ext_get_actual_len(ex
) <
1961 le32_to_cpu(newext
->ee_block
))) {
1964 } else if ((ex
> EXT_FIRST_EXTENT(eh
)) &&
1965 (le32_to_cpu(newext
->ee_block
) +
1966 ext4_ext_get_actual_len(newext
) <
1967 le32_to_cpu(ex
->ee_block
)))
1970 /* Try to append newex to the ex */
1971 if (ext4_can_extents_be_merged(inode
, ex
, newext
)) {
1972 ext_debug("append [%d]%d block to %u:[%d]%d"
1974 ext4_ext_is_unwritten(newext
),
1975 ext4_ext_get_actual_len(newext
),
1976 le32_to_cpu(ex
->ee_block
),
1977 ext4_ext_is_unwritten(ex
),
1978 ext4_ext_get_actual_len(ex
),
1979 ext4_ext_pblock(ex
));
1980 err
= ext4_ext_get_access(handle
, inode
,
1984 unwritten
= ext4_ext_is_unwritten(ex
);
1985 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
1986 + ext4_ext_get_actual_len(newext
));
1988 ext4_ext_mark_unwritten(ex
);
1989 eh
= path
[depth
].p_hdr
;
1995 /* Try to prepend newex to the ex */
1996 if (ext4_can_extents_be_merged(inode
, newext
, ex
)) {
1997 ext_debug("prepend %u[%d]%d block to %u:[%d]%d"
1999 le32_to_cpu(newext
->ee_block
),
2000 ext4_ext_is_unwritten(newext
),
2001 ext4_ext_get_actual_len(newext
),
2002 le32_to_cpu(ex
->ee_block
),
2003 ext4_ext_is_unwritten(ex
),
2004 ext4_ext_get_actual_len(ex
),
2005 ext4_ext_pblock(ex
));
2006 err
= ext4_ext_get_access(handle
, inode
,
2011 unwritten
= ext4_ext_is_unwritten(ex
);
2012 ex
->ee_block
= newext
->ee_block
;
2013 ext4_ext_store_pblock(ex
, ext4_ext_pblock(newext
));
2014 ex
->ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
)
2015 + ext4_ext_get_actual_len(newext
));
2017 ext4_ext_mark_unwritten(ex
);
2018 eh
= path
[depth
].p_hdr
;
2024 depth
= ext_depth(inode
);
2025 eh
= path
[depth
].p_hdr
;
2026 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
))
2029 /* probably next leaf has space for us? */
2030 fex
= EXT_LAST_EXTENT(eh
);
2031 next
= EXT_MAX_BLOCKS
;
2032 if (le32_to_cpu(newext
->ee_block
) > le32_to_cpu(fex
->ee_block
))
2033 next
= ext4_ext_next_leaf_block(path
);
2034 if (next
!= EXT_MAX_BLOCKS
) {
2035 ext_debug("next leaf block - %u\n", next
);
2036 BUG_ON(npath
!= NULL
);
2037 npath
= ext4_ext_find_extent(inode
, next
, NULL
, 0);
2039 return PTR_ERR(npath
);
2040 BUG_ON(npath
->p_depth
!= path
->p_depth
);
2041 eh
= npath
[depth
].p_hdr
;
2042 if (le16_to_cpu(eh
->eh_entries
) < le16_to_cpu(eh
->eh_max
)) {
2043 ext_debug("next leaf isn't full(%d)\n",
2044 le16_to_cpu(eh
->eh_entries
));
2048 ext_debug("next leaf has no free space(%d,%d)\n",
2049 le16_to_cpu(eh
->eh_entries
), le16_to_cpu(eh
->eh_max
));
2053 * There is no free space in the found leaf.
2054 * We're gonna add a new leaf in the tree.
2056 if (gb_flags
& EXT4_GET_BLOCKS_METADATA_NOFAIL
)
2057 mb_flags
= EXT4_MB_USE_RESERVED
;
2058 err
= ext4_ext_create_new_leaf(handle
, inode
, mb_flags
, gb_flags
,
2062 depth
= ext_depth(inode
);
2063 eh
= path
[depth
].p_hdr
;
2066 nearex
= path
[depth
].p_ext
;
2068 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2073 /* there is no extent in this leaf, create first one */
2074 ext_debug("first extent in the leaf: %u:%llu:[%d]%d\n",
2075 le32_to_cpu(newext
->ee_block
),
2076 ext4_ext_pblock(newext
),
2077 ext4_ext_is_unwritten(newext
),
2078 ext4_ext_get_actual_len(newext
));
2079 nearex
= EXT_FIRST_EXTENT(eh
);
2081 if (le32_to_cpu(newext
->ee_block
)
2082 > le32_to_cpu(nearex
->ee_block
)) {
2084 ext_debug("insert %u:%llu:[%d]%d before: "
2086 le32_to_cpu(newext
->ee_block
),
2087 ext4_ext_pblock(newext
),
2088 ext4_ext_is_unwritten(newext
),
2089 ext4_ext_get_actual_len(newext
),
2094 BUG_ON(newext
->ee_block
== nearex
->ee_block
);
2095 ext_debug("insert %u:%llu:[%d]%d after: "
2097 le32_to_cpu(newext
->ee_block
),
2098 ext4_ext_pblock(newext
),
2099 ext4_ext_is_unwritten(newext
),
2100 ext4_ext_get_actual_len(newext
),
2103 len
= EXT_LAST_EXTENT(eh
) - nearex
+ 1;
2105 ext_debug("insert %u:%llu:[%d]%d: "
2106 "move %d extents from 0x%p to 0x%p\n",
2107 le32_to_cpu(newext
->ee_block
),
2108 ext4_ext_pblock(newext
),
2109 ext4_ext_is_unwritten(newext
),
2110 ext4_ext_get_actual_len(newext
),
2111 len
, nearex
, nearex
+ 1);
2112 memmove(nearex
+ 1, nearex
,
2113 len
* sizeof(struct ext4_extent
));
2117 le16_add_cpu(&eh
->eh_entries
, 1);
2118 path
[depth
].p_ext
= nearex
;
2119 nearex
->ee_block
= newext
->ee_block
;
2120 ext4_ext_store_pblock(nearex
, ext4_ext_pblock(newext
));
2121 nearex
->ee_len
= newext
->ee_len
;
2124 /* try to merge extents */
2125 if (!(gb_flags
& EXT4_GET_BLOCKS_PRE_IO
))
2126 ext4_ext_try_to_merge(handle
, inode
, path
, nearex
);
2129 /* time to correct all indexes above */
2130 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2134 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
2137 ext4_ext_drop_refs(npath
);
2142 static int ext4_fill_fiemap_extents(struct inode
*inode
,
2143 ext4_lblk_t block
, ext4_lblk_t num
,
2144 struct fiemap_extent_info
*fieinfo
)
2146 struct ext4_ext_path
*path
= NULL
;
2147 struct ext4_extent
*ex
;
2148 struct extent_status es
;
2149 ext4_lblk_t next
, next_del
, start
= 0, end
= 0;
2150 ext4_lblk_t last
= block
+ num
;
2151 int exists
, depth
= 0, err
= 0;
2152 unsigned int flags
= 0;
2153 unsigned char blksize_bits
= inode
->i_sb
->s_blocksize_bits
;
2155 while (block
< last
&& block
!= EXT_MAX_BLOCKS
) {
2157 /* find extent for this block */
2158 down_read(&EXT4_I(inode
)->i_data_sem
);
2160 path
= ext4_ext_find_extent(inode
, block
, &path
, 0);
2162 up_read(&EXT4_I(inode
)->i_data_sem
);
2163 err
= PTR_ERR(path
);
2168 depth
= ext_depth(inode
);
2169 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
2170 up_read(&EXT4_I(inode
)->i_data_sem
);
2171 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
2175 ex
= path
[depth
].p_ext
;
2176 next
= ext4_ext_next_allocated_block(path
);
2181 /* there is no extent yet, so try to allocate
2182 * all requested space */
2185 } else if (le32_to_cpu(ex
->ee_block
) > block
) {
2186 /* need to allocate space before found extent */
2188 end
= le32_to_cpu(ex
->ee_block
);
2189 if (block
+ num
< end
)
2191 } else if (block
>= le32_to_cpu(ex
->ee_block
)
2192 + ext4_ext_get_actual_len(ex
)) {
2193 /* need to allocate space after found extent */
2198 } else if (block
>= le32_to_cpu(ex
->ee_block
)) {
2200 * some part of requested space is covered
2204 end
= le32_to_cpu(ex
->ee_block
)
2205 + ext4_ext_get_actual_len(ex
);
2206 if (block
+ num
< end
)
2212 BUG_ON(end
<= start
);
2216 es
.es_len
= end
- start
;
2219 es
.es_lblk
= le32_to_cpu(ex
->ee_block
);
2220 es
.es_len
= ext4_ext_get_actual_len(ex
);
2221 es
.es_pblk
= ext4_ext_pblock(ex
);
2222 if (ext4_ext_is_unwritten(ex
))
2223 flags
|= FIEMAP_EXTENT_UNWRITTEN
;
2227 * Find delayed extent and update es accordingly. We call
2228 * it even in !exists case to find out whether es is the
2229 * last existing extent or not.
2231 next_del
= ext4_find_delayed_extent(inode
, &es
);
2232 if (!exists
&& next_del
) {
2234 flags
|= (FIEMAP_EXTENT_DELALLOC
|
2235 FIEMAP_EXTENT_UNKNOWN
);
2237 up_read(&EXT4_I(inode
)->i_data_sem
);
2239 if (unlikely(es
.es_len
== 0)) {
2240 EXT4_ERROR_INODE(inode
, "es.es_len == 0");
2246 * This is possible iff next == next_del == EXT_MAX_BLOCKS.
2247 * we need to check next == EXT_MAX_BLOCKS because it is
2248 * possible that an extent is with unwritten and delayed
2249 * status due to when an extent is delayed allocated and
2250 * is allocated by fallocate status tree will track both of
2253 * So we could return a unwritten and delayed extent, and
2254 * its block is equal to 'next'.
2256 if (next
== next_del
&& next
== EXT_MAX_BLOCKS
) {
2257 flags
|= FIEMAP_EXTENT_LAST
;
2258 if (unlikely(next_del
!= EXT_MAX_BLOCKS
||
2259 next
!= EXT_MAX_BLOCKS
)) {
2260 EXT4_ERROR_INODE(inode
,
2261 "next extent == %u, next "
2262 "delalloc extent = %u",
2270 err
= fiemap_fill_next_extent(fieinfo
,
2271 (__u64
)es
.es_lblk
<< blksize_bits
,
2272 (__u64
)es
.es_pblk
<< blksize_bits
,
2273 (__u64
)es
.es_len
<< blksize_bits
,
2283 block
= es
.es_lblk
+ es
.es_len
;
2286 ext4_ext_drop_refs(path
);
2292 * ext4_ext_put_gap_in_cache:
2293 * calculate boundaries of the gap that the requested block fits into
2294 * and cache this gap
2297 ext4_ext_put_gap_in_cache(struct inode
*inode
, struct ext4_ext_path
*path
,
2300 int depth
= ext_depth(inode
);
2301 unsigned long len
= 0;
2302 ext4_lblk_t lblock
= 0;
2303 struct ext4_extent
*ex
;
2305 ex
= path
[depth
].p_ext
;
2308 * there is no extent yet, so gap is [0;-] and we
2311 ext_debug("cache gap(whole file):");
2312 } else if (block
< le32_to_cpu(ex
->ee_block
)) {
2314 len
= le32_to_cpu(ex
->ee_block
) - block
;
2315 ext_debug("cache gap(before): %u [%u:%u]",
2317 le32_to_cpu(ex
->ee_block
),
2318 ext4_ext_get_actual_len(ex
));
2319 if (!ext4_find_delalloc_range(inode
, lblock
, lblock
+ len
- 1))
2320 ext4_es_insert_extent(inode
, lblock
, len
, ~0,
2321 EXTENT_STATUS_HOLE
);
2322 } else if (block
>= le32_to_cpu(ex
->ee_block
)
2323 + ext4_ext_get_actual_len(ex
)) {
2325 lblock
= le32_to_cpu(ex
->ee_block
)
2326 + ext4_ext_get_actual_len(ex
);
2328 next
= ext4_ext_next_allocated_block(path
);
2329 ext_debug("cache gap(after): [%u:%u] %u",
2330 le32_to_cpu(ex
->ee_block
),
2331 ext4_ext_get_actual_len(ex
),
2333 BUG_ON(next
== lblock
);
2334 len
= next
- lblock
;
2335 if (!ext4_find_delalloc_range(inode
, lblock
, lblock
+ len
- 1))
2336 ext4_es_insert_extent(inode
, lblock
, len
, ~0,
2337 EXTENT_STATUS_HOLE
);
2342 ext_debug(" -> %u:%lu\n", lblock
, len
);
2347 * removes index from the index block.
2349 static int ext4_ext_rm_idx(handle_t
*handle
, struct inode
*inode
,
2350 struct ext4_ext_path
*path
, int depth
)
2355 /* free index block */
2357 path
= path
+ depth
;
2358 leaf
= ext4_idx_pblock(path
->p_idx
);
2359 if (unlikely(path
->p_hdr
->eh_entries
== 0)) {
2360 EXT4_ERROR_INODE(inode
, "path->p_hdr->eh_entries == 0");
2363 err
= ext4_ext_get_access(handle
, inode
, path
);
2367 if (path
->p_idx
!= EXT_LAST_INDEX(path
->p_hdr
)) {
2368 int len
= EXT_LAST_INDEX(path
->p_hdr
) - path
->p_idx
;
2369 len
*= sizeof(struct ext4_extent_idx
);
2370 memmove(path
->p_idx
, path
->p_idx
+ 1, len
);
2373 le16_add_cpu(&path
->p_hdr
->eh_entries
, -1);
2374 err
= ext4_ext_dirty(handle
, inode
, path
);
2377 ext_debug("index is empty, remove it, free block %llu\n", leaf
);
2378 trace_ext4_ext_rm_idx(inode
, leaf
);
2380 ext4_free_blocks(handle
, inode
, NULL
, leaf
, 1,
2381 EXT4_FREE_BLOCKS_METADATA
| EXT4_FREE_BLOCKS_FORGET
);
2383 while (--depth
>= 0) {
2384 if (path
->p_idx
!= EXT_FIRST_INDEX(path
->p_hdr
))
2387 err
= ext4_ext_get_access(handle
, inode
, path
);
2390 path
->p_idx
->ei_block
= (path
+1)->p_idx
->ei_block
;
2391 err
= ext4_ext_dirty(handle
, inode
, path
);
2399 * ext4_ext_calc_credits_for_single_extent:
2400 * This routine returns max. credits that needed to insert an extent
2401 * to the extent tree.
2402 * When pass the actual path, the caller should calculate credits
2405 int ext4_ext_calc_credits_for_single_extent(struct inode
*inode
, int nrblocks
,
2406 struct ext4_ext_path
*path
)
2409 int depth
= ext_depth(inode
);
2412 /* probably there is space in leaf? */
2413 if (le16_to_cpu(path
[depth
].p_hdr
->eh_entries
)
2414 < le16_to_cpu(path
[depth
].p_hdr
->eh_max
)) {
2417 * There are some space in the leaf tree, no
2418 * need to account for leaf block credit
2420 * bitmaps and block group descriptor blocks
2421 * and other metadata blocks still need to be
2424 /* 1 bitmap, 1 block group descriptor */
2425 ret
= 2 + EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
2430 return ext4_chunk_trans_blocks(inode
, nrblocks
);
2434 * How many index/leaf blocks need to change/allocate to add @extents extents?
2436 * If we add a single extent, then in the worse case, each tree level
2437 * index/leaf need to be changed in case of the tree split.
2439 * If more extents are inserted, they could cause the whole tree split more
2440 * than once, but this is really rare.
2442 int ext4_ext_index_trans_blocks(struct inode
*inode
, int extents
)
2447 /* If we are converting the inline data, only one is needed here. */
2448 if (ext4_has_inline_data(inode
))
2451 depth
= ext_depth(inode
);
2461 static inline int get_default_free_blocks_flags(struct inode
*inode
)
2463 if (S_ISDIR(inode
->i_mode
) || S_ISLNK(inode
->i_mode
))
2464 return EXT4_FREE_BLOCKS_METADATA
| EXT4_FREE_BLOCKS_FORGET
;
2465 else if (ext4_should_journal_data(inode
))
2466 return EXT4_FREE_BLOCKS_FORGET
;
2470 static int ext4_remove_blocks(handle_t
*handle
, struct inode
*inode
,
2471 struct ext4_extent
*ex
,
2472 long long *partial_cluster
,
2473 ext4_lblk_t from
, ext4_lblk_t to
)
2475 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2476 unsigned short ee_len
= ext4_ext_get_actual_len(ex
);
2478 int flags
= get_default_free_blocks_flags(inode
);
2481 * For bigalloc file systems, we never free a partial cluster
2482 * at the beginning of the extent. Instead, we make a note
2483 * that we tried freeing the cluster, and check to see if we
2484 * need to free it on a subsequent call to ext4_remove_blocks,
2485 * or at the end of the ext4_truncate() operation.
2487 flags
|= EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER
;
2489 trace_ext4_remove_blocks(inode
, ex
, from
, to
, *partial_cluster
);
2491 * If we have a partial cluster, and it's different from the
2492 * cluster of the last block, we need to explicitly free the
2493 * partial cluster here.
2495 pblk
= ext4_ext_pblock(ex
) + ee_len
- 1;
2496 if ((*partial_cluster
> 0) &&
2497 (EXT4_B2C(sbi
, pblk
) != *partial_cluster
)) {
2498 ext4_free_blocks(handle
, inode
, NULL
,
2499 EXT4_C2B(sbi
, *partial_cluster
),
2500 sbi
->s_cluster_ratio
, flags
);
2501 *partial_cluster
= 0;
2504 #ifdef EXTENTS_STATS
2506 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2507 spin_lock(&sbi
->s_ext_stats_lock
);
2508 sbi
->s_ext_blocks
+= ee_len
;
2509 sbi
->s_ext_extents
++;
2510 if (ee_len
< sbi
->s_ext_min
)
2511 sbi
->s_ext_min
= ee_len
;
2512 if (ee_len
> sbi
->s_ext_max
)
2513 sbi
->s_ext_max
= ee_len
;
2514 if (ext_depth(inode
) > sbi
->s_depth_max
)
2515 sbi
->s_depth_max
= ext_depth(inode
);
2516 spin_unlock(&sbi
->s_ext_stats_lock
);
2519 if (from
>= le32_to_cpu(ex
->ee_block
)
2520 && to
== le32_to_cpu(ex
->ee_block
) + ee_len
- 1) {
2523 unsigned int unaligned
;
2525 num
= le32_to_cpu(ex
->ee_block
) + ee_len
- from
;
2526 pblk
= ext4_ext_pblock(ex
) + ee_len
- num
;
2528 * Usually we want to free partial cluster at the end of the
2529 * extent, except for the situation when the cluster is still
2530 * used by any other extent (partial_cluster is negative).
2532 if (*partial_cluster
< 0 &&
2533 -(*partial_cluster
) == EXT4_B2C(sbi
, pblk
+ num
- 1))
2534 flags
|= EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER
;
2536 ext_debug("free last %u blocks starting %llu partial %lld\n",
2537 num
, pblk
, *partial_cluster
);
2538 ext4_free_blocks(handle
, inode
, NULL
, pblk
, num
, flags
);
2540 * If the block range to be freed didn't start at the
2541 * beginning of a cluster, and we removed the entire
2542 * extent and the cluster is not used by any other extent,
2543 * save the partial cluster here, since we might need to
2544 * delete if we determine that the truncate operation has
2545 * removed all of the blocks in the cluster.
2547 * On the other hand, if we did not manage to free the whole
2548 * extent, we have to mark the cluster as used (store negative
2549 * cluster number in partial_cluster).
2551 unaligned
= EXT4_PBLK_COFF(sbi
, pblk
);
2552 if (unaligned
&& (ee_len
== num
) &&
2553 (*partial_cluster
!= -((long long)EXT4_B2C(sbi
, pblk
))))
2554 *partial_cluster
= EXT4_B2C(sbi
, pblk
);
2556 *partial_cluster
= -((long long)EXT4_B2C(sbi
, pblk
));
2557 else if (*partial_cluster
> 0)
2558 *partial_cluster
= 0;
2560 ext4_error(sbi
->s_sb
, "strange request: removal(2) "
2561 "%u-%u from %u:%u\n",
2562 from
, to
, le32_to_cpu(ex
->ee_block
), ee_len
);
2568 * ext4_ext_rm_leaf() Removes the extents associated with the
2569 * blocks appearing between "start" and "end", and splits the extents
2570 * if "start" and "end" appear in the same extent
2572 * @handle: The journal handle
2573 * @inode: The files inode
2574 * @path: The path to the leaf
2575 * @partial_cluster: The cluster which we'll have to free if all extents
2576 * has been released from it. It gets negative in case
2577 * that the cluster is still used.
2578 * @start: The first block to remove
2579 * @end: The last block to remove
2582 ext4_ext_rm_leaf(handle_t
*handle
, struct inode
*inode
,
2583 struct ext4_ext_path
*path
,
2584 long long *partial_cluster
,
2585 ext4_lblk_t start
, ext4_lblk_t end
)
2587 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
2588 int err
= 0, correct_index
= 0;
2589 int depth
= ext_depth(inode
), credits
;
2590 struct ext4_extent_header
*eh
;
2593 ext4_lblk_t ex_ee_block
;
2594 unsigned short ex_ee_len
;
2595 unsigned unwritten
= 0;
2596 struct ext4_extent
*ex
;
2599 /* the header must be checked already in ext4_ext_remove_space() */
2600 ext_debug("truncate since %u in leaf to %u\n", start
, end
);
2601 if (!path
[depth
].p_hdr
)
2602 path
[depth
].p_hdr
= ext_block_hdr(path
[depth
].p_bh
);
2603 eh
= path
[depth
].p_hdr
;
2604 if (unlikely(path
[depth
].p_hdr
== NULL
)) {
2605 EXT4_ERROR_INODE(inode
, "path[%d].p_hdr == NULL", depth
);
2608 /* find where to start removing */
2609 ex
= path
[depth
].p_ext
;
2611 ex
= EXT_LAST_EXTENT(eh
);
2613 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2614 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2617 * If we're starting with an extent other than the last one in the
2618 * node, we need to see if it shares a cluster with the extent to
2619 * the right (towards the end of the file). If its leftmost cluster
2620 * is this extent's rightmost cluster and it is not cluster aligned,
2621 * we'll mark it as a partial that is not to be deallocated.
2624 if (ex
!= EXT_LAST_EXTENT(eh
)) {
2625 ext4_fsblk_t current_pblk
, right_pblk
;
2626 long long current_cluster
, right_cluster
;
2628 current_pblk
= ext4_ext_pblock(ex
) + ex_ee_len
- 1;
2629 current_cluster
= (long long)EXT4_B2C(sbi
, current_pblk
);
2630 right_pblk
= ext4_ext_pblock(ex
+ 1);
2631 right_cluster
= (long long)EXT4_B2C(sbi
, right_pblk
);
2632 if (current_cluster
== right_cluster
&&
2633 EXT4_PBLK_COFF(sbi
, right_pblk
))
2634 *partial_cluster
= -right_cluster
;
2637 trace_ext4_ext_rm_leaf(inode
, start
, ex
, *partial_cluster
);
2639 while (ex
>= EXT_FIRST_EXTENT(eh
) &&
2640 ex_ee_block
+ ex_ee_len
> start
) {
2642 if (ext4_ext_is_unwritten(ex
))
2647 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block
,
2648 unwritten
, ex_ee_len
);
2649 path
[depth
].p_ext
= ex
;
2651 a
= ex_ee_block
> start
? ex_ee_block
: start
;
2652 b
= ex_ee_block
+ex_ee_len
- 1 < end
?
2653 ex_ee_block
+ex_ee_len
- 1 : end
;
2655 ext_debug(" border %u:%u\n", a
, b
);
2657 /* If this extent is beyond the end of the hole, skip it */
2658 if (end
< ex_ee_block
) {
2660 * We're going to skip this extent and move to another,
2661 * so if this extent is not cluster aligned we have
2662 * to mark the current cluster as used to avoid
2663 * accidentally freeing it later on
2665 pblk
= ext4_ext_pblock(ex
);
2666 if (EXT4_PBLK_COFF(sbi
, pblk
))
2668 -((long long)EXT4_B2C(sbi
, pblk
));
2670 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2671 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2673 } else if (b
!= ex_ee_block
+ ex_ee_len
- 1) {
2674 EXT4_ERROR_INODE(inode
,
2675 "can not handle truncate %u:%u "
2677 start
, end
, ex_ee_block
,
2678 ex_ee_block
+ ex_ee_len
- 1);
2681 } else if (a
!= ex_ee_block
) {
2682 /* remove tail of the extent */
2683 num
= a
- ex_ee_block
;
2685 /* remove whole extent: excellent! */
2689 * 3 for leaf, sb, and inode plus 2 (bmap and group
2690 * descriptor) for each block group; assume two block
2691 * groups plus ex_ee_len/blocks_per_block_group for
2694 credits
= 7 + 2*(ex_ee_len
/EXT4_BLOCKS_PER_GROUP(inode
->i_sb
));
2695 if (ex
== EXT_FIRST_EXTENT(eh
)) {
2697 credits
+= (ext_depth(inode
)) + 1;
2699 credits
+= EXT4_MAXQUOTAS_TRANS_BLOCKS(inode
->i_sb
);
2701 err
= ext4_ext_truncate_extend_restart(handle
, inode
, credits
);
2705 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
2709 err
= ext4_remove_blocks(handle
, inode
, ex
, partial_cluster
,
2715 /* this extent is removed; mark slot entirely unused */
2716 ext4_ext_store_pblock(ex
, 0);
2718 ex
->ee_len
= cpu_to_le16(num
);
2720 * Do not mark unwritten if all the blocks in the
2721 * extent have been removed.
2723 if (unwritten
&& num
)
2724 ext4_ext_mark_unwritten(ex
);
2726 * If the extent was completely released,
2727 * we need to remove it from the leaf
2730 if (end
!= EXT_MAX_BLOCKS
- 1) {
2732 * For hole punching, we need to scoot all the
2733 * extents up when an extent is removed so that
2734 * we dont have blank extents in the middle
2736 memmove(ex
, ex
+1, (EXT_LAST_EXTENT(eh
) - ex
) *
2737 sizeof(struct ext4_extent
));
2739 /* Now get rid of the one at the end */
2740 memset(EXT_LAST_EXTENT(eh
), 0,
2741 sizeof(struct ext4_extent
));
2743 le16_add_cpu(&eh
->eh_entries
, -1);
2744 } else if (*partial_cluster
> 0)
2745 *partial_cluster
= 0;
2747 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
2751 ext_debug("new extent: %u:%u:%llu\n", ex_ee_block
, num
,
2752 ext4_ext_pblock(ex
));
2754 ex_ee_block
= le32_to_cpu(ex
->ee_block
);
2755 ex_ee_len
= ext4_ext_get_actual_len(ex
);
2758 if (correct_index
&& eh
->eh_entries
)
2759 err
= ext4_ext_correct_indexes(handle
, inode
, path
);
2762 * If there's a partial cluster and at least one extent remains in
2763 * the leaf, free the partial cluster if it isn't shared with the
2764 * current extent. If there's a partial cluster and no extents
2765 * remain in the leaf, it can't be freed here. It can only be
2766 * freed when it's possible to determine if it's not shared with
2767 * any other extent - when the next leaf is processed or when space
2768 * removal is complete.
2770 if (*partial_cluster
> 0 && eh
->eh_entries
&&
2771 (EXT4_B2C(sbi
, ext4_ext_pblock(ex
) + ex_ee_len
- 1) !=
2772 *partial_cluster
)) {
2773 int flags
= get_default_free_blocks_flags(inode
);
2775 ext4_free_blocks(handle
, inode
, NULL
,
2776 EXT4_C2B(sbi
, *partial_cluster
),
2777 sbi
->s_cluster_ratio
, flags
);
2778 *partial_cluster
= 0;
2781 /* if this leaf is free, then we should
2782 * remove it from index block above */
2783 if (err
== 0 && eh
->eh_entries
== 0 && path
[depth
].p_bh
!= NULL
)
2784 err
= ext4_ext_rm_idx(handle
, inode
, path
, depth
);
2791 * ext4_ext_more_to_rm:
2792 * returns 1 if current index has to be freed (even partial)
2795 ext4_ext_more_to_rm(struct ext4_ext_path
*path
)
2797 BUG_ON(path
->p_idx
== NULL
);
2799 if (path
->p_idx
< EXT_FIRST_INDEX(path
->p_hdr
))
2803 * if truncate on deeper level happened, it wasn't partial,
2804 * so we have to consider current index for truncation
2806 if (le16_to_cpu(path
->p_hdr
->eh_entries
) == path
->p_block
)
2811 int ext4_ext_remove_space(struct inode
*inode
, ext4_lblk_t start
,
2814 struct super_block
*sb
= inode
->i_sb
;
2815 int depth
= ext_depth(inode
);
2816 struct ext4_ext_path
*path
= NULL
;
2817 long long partial_cluster
= 0;
2821 ext_debug("truncate since %u to %u\n", start
, end
);
2823 /* probably first extent we're gonna free will be last in block */
2824 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, depth
+ 1);
2826 return PTR_ERR(handle
);
2829 trace_ext4_ext_remove_space(inode
, start
, end
, depth
);
2832 * Check if we are removing extents inside the extent tree. If that
2833 * is the case, we are going to punch a hole inside the extent tree
2834 * so we have to check whether we need to split the extent covering
2835 * the last block to remove so we can easily remove the part of it
2836 * in ext4_ext_rm_leaf().
2838 if (end
< EXT_MAX_BLOCKS
- 1) {
2839 struct ext4_extent
*ex
;
2840 ext4_lblk_t ee_block
;
2842 /* find extent for this block */
2843 path
= ext4_ext_find_extent(inode
, end
, NULL
, EXT4_EX_NOCACHE
);
2845 ext4_journal_stop(handle
);
2846 return PTR_ERR(path
);
2848 depth
= ext_depth(inode
);
2849 /* Leaf not may not exist only if inode has no blocks at all */
2850 ex
= path
[depth
].p_ext
;
2853 EXT4_ERROR_INODE(inode
,
2854 "path[%d].p_hdr == NULL",
2861 ee_block
= le32_to_cpu(ex
->ee_block
);
2864 * See if the last block is inside the extent, if so split
2865 * the extent at 'end' block so we can easily remove the
2866 * tail of the first part of the split extent in
2867 * ext4_ext_rm_leaf().
2869 if (end
>= ee_block
&&
2870 end
< ee_block
+ ext4_ext_get_actual_len(ex
) - 1) {
2872 * Split the extent in two so that 'end' is the last
2873 * block in the first new extent. Also we should not
2874 * fail removing space due to ENOSPC so try to use
2875 * reserved block if that happens.
2877 err
= ext4_force_split_extent_at(handle
, inode
, &path
,
2884 * We start scanning from right side, freeing all the blocks
2885 * after i_size and walking into the tree depth-wise.
2887 depth
= ext_depth(inode
);
2892 le16_to_cpu(path
[k
].p_hdr
->eh_entries
)+1;
2894 path
= kzalloc(sizeof(struct ext4_ext_path
) * (depth
+ 1),
2897 ext4_journal_stop(handle
);
2900 path
[0].p_maxdepth
= path
[0].p_depth
= depth
;
2901 path
[0].p_hdr
= ext_inode_hdr(inode
);
2904 if (ext4_ext_check(inode
, path
[0].p_hdr
, depth
, 0)) {
2911 while (i
>= 0 && err
== 0) {
2913 /* this is leaf block */
2914 err
= ext4_ext_rm_leaf(handle
, inode
, path
,
2915 &partial_cluster
, start
,
2917 /* root level has p_bh == NULL, brelse() eats this */
2918 brelse(path
[i
].p_bh
);
2919 path
[i
].p_bh
= NULL
;
2924 /* this is index block */
2925 if (!path
[i
].p_hdr
) {
2926 ext_debug("initialize header\n");
2927 path
[i
].p_hdr
= ext_block_hdr(path
[i
].p_bh
);
2930 if (!path
[i
].p_idx
) {
2931 /* this level hasn't been touched yet */
2932 path
[i
].p_idx
= EXT_LAST_INDEX(path
[i
].p_hdr
);
2933 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
)+1;
2934 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2936 le16_to_cpu(path
[i
].p_hdr
->eh_entries
));
2938 /* we were already here, see at next index */
2942 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2943 i
, EXT_FIRST_INDEX(path
[i
].p_hdr
),
2945 if (ext4_ext_more_to_rm(path
+ i
)) {
2946 struct buffer_head
*bh
;
2947 /* go to the next level */
2948 ext_debug("move to level %d (block %llu)\n",
2949 i
+ 1, ext4_idx_pblock(path
[i
].p_idx
));
2950 memset(path
+ i
+ 1, 0, sizeof(*path
));
2951 bh
= read_extent_tree_block(inode
,
2952 ext4_idx_pblock(path
[i
].p_idx
), depth
- i
- 1,
2955 /* should we reset i_size? */
2959 /* Yield here to deal with large extent trees.
2960 * Should be a no-op if we did IO above. */
2962 if (WARN_ON(i
+ 1 > depth
)) {
2966 path
[i
+ 1].p_bh
= bh
;
2968 /* save actual number of indexes since this
2969 * number is changed at the next iteration */
2970 path
[i
].p_block
= le16_to_cpu(path
[i
].p_hdr
->eh_entries
);
2973 /* we finished processing this index, go up */
2974 if (path
[i
].p_hdr
->eh_entries
== 0 && i
> 0) {
2975 /* index is empty, remove it;
2976 * handle must be already prepared by the
2977 * truncatei_leaf() */
2978 err
= ext4_ext_rm_idx(handle
, inode
, path
, i
);
2980 /* root level has p_bh == NULL, brelse() eats this */
2981 brelse(path
[i
].p_bh
);
2982 path
[i
].p_bh
= NULL
;
2984 ext_debug("return to level %d\n", i
);
2988 trace_ext4_ext_remove_space_done(inode
, start
, end
, depth
,
2989 partial_cluster
, path
->p_hdr
->eh_entries
);
2991 /* If we still have something in the partial cluster and we have removed
2992 * even the first extent, then we should free the blocks in the partial
2993 * cluster as well. */
2994 if (partial_cluster
> 0 && path
->p_hdr
->eh_entries
== 0) {
2995 int flags
= get_default_free_blocks_flags(inode
);
2997 ext4_free_blocks(handle
, inode
, NULL
,
2998 EXT4_C2B(EXT4_SB(sb
), partial_cluster
),
2999 EXT4_SB(sb
)->s_cluster_ratio
, flags
);
3000 partial_cluster
= 0;
3003 /* TODO: flexible tree reduction should be here */
3004 if (path
->p_hdr
->eh_entries
== 0) {
3006 * truncate to zero freed all the tree,
3007 * so we need to correct eh_depth
3009 err
= ext4_ext_get_access(handle
, inode
, path
);
3011 ext_inode_hdr(inode
)->eh_depth
= 0;
3012 ext_inode_hdr(inode
)->eh_max
=
3013 cpu_to_le16(ext4_ext_space_root(inode
, 0));
3014 err
= ext4_ext_dirty(handle
, inode
, path
);
3018 ext4_ext_drop_refs(path
);
3023 ext4_journal_stop(handle
);
3029 * called at mount time
3031 void ext4_ext_init(struct super_block
*sb
)
3034 * possible initialization would be here
3037 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
)) {
3038 #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
3039 printk(KERN_INFO
"EXT4-fs: file extents enabled"
3040 #ifdef AGGRESSIVE_TEST
3041 ", aggressive tests"
3043 #ifdef CHECK_BINSEARCH
3046 #ifdef EXTENTS_STATS
3051 #ifdef EXTENTS_STATS
3052 spin_lock_init(&EXT4_SB(sb
)->s_ext_stats_lock
);
3053 EXT4_SB(sb
)->s_ext_min
= 1 << 30;
3054 EXT4_SB(sb
)->s_ext_max
= 0;
3060 * called at umount time
3062 void ext4_ext_release(struct super_block
*sb
)
3064 if (!EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_EXTENTS
))
3067 #ifdef EXTENTS_STATS
3068 if (EXT4_SB(sb
)->s_ext_blocks
&& EXT4_SB(sb
)->s_ext_extents
) {
3069 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
3070 printk(KERN_ERR
"EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
3071 sbi
->s_ext_blocks
, sbi
->s_ext_extents
,
3072 sbi
->s_ext_blocks
/ sbi
->s_ext_extents
);
3073 printk(KERN_ERR
"EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
3074 sbi
->s_ext_min
, sbi
->s_ext_max
, sbi
->s_depth_max
);
3079 static int ext4_zeroout_es(struct inode
*inode
, struct ext4_extent
*ex
)
3081 ext4_lblk_t ee_block
;
3082 ext4_fsblk_t ee_pblock
;
3083 unsigned int ee_len
;
3085 ee_block
= le32_to_cpu(ex
->ee_block
);
3086 ee_len
= ext4_ext_get_actual_len(ex
);
3087 ee_pblock
= ext4_ext_pblock(ex
);
3092 return ext4_es_insert_extent(inode
, ee_block
, ee_len
, ee_pblock
,
3093 EXTENT_STATUS_WRITTEN
);
3096 /* FIXME!! we need to try to merge to left or right after zero-out */
3097 static int ext4_ext_zeroout(struct inode
*inode
, struct ext4_extent
*ex
)
3099 ext4_fsblk_t ee_pblock
;
3100 unsigned int ee_len
;
3103 ee_len
= ext4_ext_get_actual_len(ex
);
3104 ee_pblock
= ext4_ext_pblock(ex
);
3106 ret
= sb_issue_zeroout(inode
->i_sb
, ee_pblock
, ee_len
, GFP_NOFS
);
3114 * ext4_split_extent_at() splits an extent at given block.
3116 * @handle: the journal handle
3117 * @inode: the file inode
3118 * @path: the path to the extent
3119 * @split: the logical block where the extent is splitted.
3120 * @split_flags: indicates if the extent could be zeroout if split fails, and
3121 * the states(init or unwritten) of new extents.
3122 * @flags: flags used to insert new extent to extent tree.
3125 * Splits extent [a, b] into two extents [a, @split) and [@split, b], states
3126 * of which are deterimined by split_flag.
3128 * There are two cases:
3129 * a> the extent are splitted into two extent.
3130 * b> split is not needed, and just mark the extent.
3132 * return 0 on success.
3134 static int ext4_split_extent_at(handle_t
*handle
,
3135 struct inode
*inode
,
3136 struct ext4_ext_path
**ppath
,
3141 struct ext4_ext_path
*path
= *ppath
;
3142 ext4_fsblk_t newblock
;
3143 ext4_lblk_t ee_block
;
3144 struct ext4_extent
*ex
, newex
, orig_ex
, zero_ex
;
3145 struct ext4_extent
*ex2
= NULL
;
3146 unsigned int ee_len
, depth
;
3149 BUG_ON((split_flag
& (EXT4_EXT_DATA_VALID1
| EXT4_EXT_DATA_VALID2
)) ==
3150 (EXT4_EXT_DATA_VALID1
| EXT4_EXT_DATA_VALID2
));
3152 ext_debug("ext4_split_extents_at: inode %lu, logical"
3153 "block %llu\n", inode
->i_ino
, (unsigned long long)split
);
3155 ext4_ext_show_leaf(inode
, path
);
3157 depth
= ext_depth(inode
);
3158 ex
= path
[depth
].p_ext
;
3159 ee_block
= le32_to_cpu(ex
->ee_block
);
3160 ee_len
= ext4_ext_get_actual_len(ex
);
3161 newblock
= split
- ee_block
+ ext4_ext_pblock(ex
);
3163 BUG_ON(split
< ee_block
|| split
>= (ee_block
+ ee_len
));
3164 BUG_ON(!ext4_ext_is_unwritten(ex
) &&
3165 split_flag
& (EXT4_EXT_MAY_ZEROOUT
|
3166 EXT4_EXT_MARK_UNWRIT1
|
3167 EXT4_EXT_MARK_UNWRIT2
));
3169 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3173 if (split
== ee_block
) {
3175 * case b: block @split is the block that the extent begins with
3176 * then we just change the state of the extent, and splitting
3179 if (split_flag
& EXT4_EXT_MARK_UNWRIT2
)
3180 ext4_ext_mark_unwritten(ex
);
3182 ext4_ext_mark_initialized(ex
);
3184 if (!(flags
& EXT4_GET_BLOCKS_PRE_IO
))
3185 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3187 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3192 memcpy(&orig_ex
, ex
, sizeof(orig_ex
));
3193 ex
->ee_len
= cpu_to_le16(split
- ee_block
);
3194 if (split_flag
& EXT4_EXT_MARK_UNWRIT1
)
3195 ext4_ext_mark_unwritten(ex
);
3198 * path may lead to new leaf, not to original leaf any more
3199 * after ext4_ext_insert_extent() returns,
3201 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
3203 goto fix_extent_len
;
3206 ex2
->ee_block
= cpu_to_le32(split
);
3207 ex2
->ee_len
= cpu_to_le16(ee_len
- (split
- ee_block
));
3208 ext4_ext_store_pblock(ex2
, newblock
);
3209 if (split_flag
& EXT4_EXT_MARK_UNWRIT2
)
3210 ext4_ext_mark_unwritten(ex2
);
3212 err
= ext4_ext_insert_extent(handle
, inode
, ppath
, &newex
, flags
);
3213 if (err
== -ENOSPC
&& (EXT4_EXT_MAY_ZEROOUT
& split_flag
)) {
3214 if (split_flag
& (EXT4_EXT_DATA_VALID1
|EXT4_EXT_DATA_VALID2
)) {
3215 if (split_flag
& EXT4_EXT_DATA_VALID1
) {
3216 err
= ext4_ext_zeroout(inode
, ex2
);
3217 zero_ex
.ee_block
= ex2
->ee_block
;
3218 zero_ex
.ee_len
= cpu_to_le16(
3219 ext4_ext_get_actual_len(ex2
));
3220 ext4_ext_store_pblock(&zero_ex
,
3221 ext4_ext_pblock(ex2
));
3223 err
= ext4_ext_zeroout(inode
, ex
);
3224 zero_ex
.ee_block
= ex
->ee_block
;
3225 zero_ex
.ee_len
= cpu_to_le16(
3226 ext4_ext_get_actual_len(ex
));
3227 ext4_ext_store_pblock(&zero_ex
,
3228 ext4_ext_pblock(ex
));
3231 err
= ext4_ext_zeroout(inode
, &orig_ex
);
3232 zero_ex
.ee_block
= orig_ex
.ee_block
;
3233 zero_ex
.ee_len
= cpu_to_le16(
3234 ext4_ext_get_actual_len(&orig_ex
));
3235 ext4_ext_store_pblock(&zero_ex
,
3236 ext4_ext_pblock(&orig_ex
));
3240 goto fix_extent_len
;
3241 /* update the extent length and mark as initialized */
3242 ex
->ee_len
= cpu_to_le16(ee_len
);
3243 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3244 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3246 goto fix_extent_len
;
3248 /* update extent status tree */
3249 err
= ext4_zeroout_es(inode
, &zero_ex
);
3253 goto fix_extent_len
;
3256 ext4_ext_show_leaf(inode
, path
);
3260 ex
->ee_len
= orig_ex
.ee_len
;
3261 ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3266 * ext4_split_extents() splits an extent and mark extent which is covered
3267 * by @map as split_flags indicates
3269 * It may result in splitting the extent into multiple extents (up to three)
3270 * There are three possibilities:
3271 * a> There is no split required
3272 * b> Splits in two extents: Split is happening at either end of the extent
3273 * c> Splits in three extents: Somone is splitting in middle of the extent
3276 static int ext4_split_extent(handle_t
*handle
,
3277 struct inode
*inode
,
3278 struct ext4_ext_path
**ppath
,
3279 struct ext4_map_blocks
*map
,
3283 struct ext4_ext_path
*path
= *ppath
;
3284 ext4_lblk_t ee_block
;
3285 struct ext4_extent
*ex
;
3286 unsigned int ee_len
, depth
;
3289 int split_flag1
, flags1
;
3290 int allocated
= map
->m_len
;
3292 depth
= ext_depth(inode
);
3293 ex
= path
[depth
].p_ext
;
3294 ee_block
= le32_to_cpu(ex
->ee_block
);
3295 ee_len
= ext4_ext_get_actual_len(ex
);
3296 unwritten
= ext4_ext_is_unwritten(ex
);
3298 if (map
->m_lblk
+ map
->m_len
< ee_block
+ ee_len
) {
3299 split_flag1
= split_flag
& EXT4_EXT_MAY_ZEROOUT
;
3300 flags1
= flags
| EXT4_GET_BLOCKS_PRE_IO
;
3302 split_flag1
|= EXT4_EXT_MARK_UNWRIT1
|
3303 EXT4_EXT_MARK_UNWRIT2
;
3304 if (split_flag
& EXT4_EXT_DATA_VALID2
)
3305 split_flag1
|= EXT4_EXT_DATA_VALID1
;
3306 err
= ext4_split_extent_at(handle
, inode
, ppath
,
3307 map
->m_lblk
+ map
->m_len
, split_flag1
, flags1
);
3311 allocated
= ee_len
- (map
->m_lblk
- ee_block
);
3314 * Update path is required because previous ext4_split_extent_at() may
3315 * result in split of original leaf or extent zeroout.
3317 path
= ext4_ext_find_extent(inode
, map
->m_lblk
, ppath
, 0);
3319 return PTR_ERR(path
);
3320 depth
= ext_depth(inode
);
3321 ex
= path
[depth
].p_ext
;
3323 EXT4_ERROR_INODE(inode
, "unexpected hole at %lu",
3324 (unsigned long) map
->m_lblk
);
3327 unwritten
= ext4_ext_is_unwritten(ex
);
3330 if (map
->m_lblk
>= ee_block
) {
3331 split_flag1
= split_flag
& EXT4_EXT_DATA_VALID2
;
3333 split_flag1
|= EXT4_EXT_MARK_UNWRIT1
;
3334 split_flag1
|= split_flag
& (EXT4_EXT_MAY_ZEROOUT
|
3335 EXT4_EXT_MARK_UNWRIT2
);
3337 err
= ext4_split_extent_at(handle
, inode
, ppath
,
3338 map
->m_lblk
, split_flag1
, flags
);
3343 ext4_ext_show_leaf(inode
, path
);
3345 return err
? err
: allocated
;
3349 * This function is called by ext4_ext_map_blocks() if someone tries to write
3350 * to an unwritten extent. It may result in splitting the unwritten
3351 * extent into multiple extents (up to three - one initialized and two
3353 * There are three possibilities:
3354 * a> There is no split required: Entire extent should be initialized
3355 * b> Splits in two extents: Write is happening at either end of the extent
3356 * c> Splits in three extents: Somone is writing in middle of the extent
3359 * - The extent pointed to by 'path' is unwritten.
3360 * - The extent pointed to by 'path' contains a superset
3361 * of the logical span [map->m_lblk, map->m_lblk + map->m_len).
3363 * Post-conditions on success:
3364 * - the returned value is the number of blocks beyond map->l_lblk
3365 * that are allocated and initialized.
3366 * It is guaranteed to be >= map->m_len.
3368 static int ext4_ext_convert_to_initialized(handle_t
*handle
,
3369 struct inode
*inode
,
3370 struct ext4_map_blocks
*map
,
3371 struct ext4_ext_path
**ppath
,
3374 struct ext4_ext_path
*path
= *ppath
;
3375 struct ext4_sb_info
*sbi
;
3376 struct ext4_extent_header
*eh
;
3377 struct ext4_map_blocks split_map
;
3378 struct ext4_extent zero_ex
;
3379 struct ext4_extent
*ex
, *abut_ex
;
3380 ext4_lblk_t ee_block
, eof_block
;
3381 unsigned int ee_len
, depth
, map_len
= map
->m_len
;
3382 int allocated
= 0, max_zeroout
= 0;
3386 ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
3387 "block %llu, max_blocks %u\n", inode
->i_ino
,
3388 (unsigned long long)map
->m_lblk
, map_len
);
3390 sbi
= EXT4_SB(inode
->i_sb
);
3391 eof_block
= (inode
->i_size
+ inode
->i_sb
->s_blocksize
- 1) >>
3392 inode
->i_sb
->s_blocksize_bits
;
3393 if (eof_block
< map
->m_lblk
+ map_len
)
3394 eof_block
= map
->m_lblk
+ map_len
;
3396 depth
= ext_depth(inode
);
3397 eh
= path
[depth
].p_hdr
;
3398 ex
= path
[depth
].p_ext
;
3399 ee_block
= le32_to_cpu(ex
->ee_block
);
3400 ee_len
= ext4_ext_get_actual_len(ex
);
3403 trace_ext4_ext_convert_to_initialized_enter(inode
, map
, ex
);
3405 /* Pre-conditions */
3406 BUG_ON(!ext4_ext_is_unwritten(ex
));
3407 BUG_ON(!in_range(map
->m_lblk
, ee_block
, ee_len
));
3410 * Attempt to transfer newly initialized blocks from the currently
3411 * unwritten extent to its neighbor. This is much cheaper
3412 * than an insertion followed by a merge as those involve costly
3413 * memmove() calls. Transferring to the left is the common case in
3414 * steady state for workloads doing fallocate(FALLOC_FL_KEEP_SIZE)
3415 * followed by append writes.
3417 * Limitations of the current logic:
3418 * - L1: we do not deal with writes covering the whole extent.
3419 * This would require removing the extent if the transfer
3421 * - L2: we only attempt to merge with an extent stored in the
3422 * same extent tree node.
3424 if ((map
->m_lblk
== ee_block
) &&
3425 /* See if we can merge left */
3426 (map_len
< ee_len
) && /*L1*/
3427 (ex
> EXT_FIRST_EXTENT(eh
))) { /*L2*/
3428 ext4_lblk_t prev_lblk
;
3429 ext4_fsblk_t prev_pblk
, ee_pblk
;
3430 unsigned int prev_len
;
3433 prev_lblk
= le32_to_cpu(abut_ex
->ee_block
);
3434 prev_len
= ext4_ext_get_actual_len(abut_ex
);
3435 prev_pblk
= ext4_ext_pblock(abut_ex
);
3436 ee_pblk
= ext4_ext_pblock(ex
);
3439 * A transfer of blocks from 'ex' to 'abut_ex' is allowed
3440 * upon those conditions:
3441 * - C1: abut_ex is initialized,
3442 * - C2: abut_ex is logically abutting ex,
3443 * - C3: abut_ex is physically abutting ex,
3444 * - C4: abut_ex can receive the additional blocks without
3445 * overflowing the (initialized) length limit.
3447 if ((!ext4_ext_is_unwritten(abut_ex
)) && /*C1*/
3448 ((prev_lblk
+ prev_len
) == ee_block
) && /*C2*/
3449 ((prev_pblk
+ prev_len
) == ee_pblk
) && /*C3*/
3450 (prev_len
< (EXT_INIT_MAX_LEN
- map_len
))) { /*C4*/
3451 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3455 trace_ext4_ext_convert_to_initialized_fastpath(inode
,
3458 /* Shift the start of ex by 'map_len' blocks */
3459 ex
->ee_block
= cpu_to_le32(ee_block
+ map_len
);
3460 ext4_ext_store_pblock(ex
, ee_pblk
+ map_len
);
3461 ex
->ee_len
= cpu_to_le16(ee_len
- map_len
);
3462 ext4_ext_mark_unwritten(ex
); /* Restore the flag */
3464 /* Extend abut_ex by 'map_len' blocks */
3465 abut_ex
->ee_len
= cpu_to_le16(prev_len
+ map_len
);
3467 /* Result: number of initialized blocks past m_lblk */
3468 allocated
= map_len
;
3470 } else if (((map
->m_lblk
+ map_len
) == (ee_block
+ ee_len
)) &&
3471 (map_len
< ee_len
) && /*L1*/
3472 ex
< EXT_LAST_EXTENT(eh
)) { /*L2*/
3473 /* See if we can merge right */
3474 ext4_lblk_t next_lblk
;
3475 ext4_fsblk_t next_pblk
, ee_pblk
;
3476 unsigned int next_len
;
3479 next_lblk
= le32_to_cpu(abut_ex
->ee_block
);
3480 next_len
= ext4_ext_get_actual_len(abut_ex
);
3481 next_pblk
= ext4_ext_pblock(abut_ex
);
3482 ee_pblk
= ext4_ext_pblock(ex
);
3485 * A transfer of blocks from 'ex' to 'abut_ex' is allowed
3486 * upon those conditions:
3487 * - C1: abut_ex is initialized,
3488 * - C2: abut_ex is logically abutting ex,
3489 * - C3: abut_ex is physically abutting ex,
3490 * - C4: abut_ex can receive the additional blocks without
3491 * overflowing the (initialized) length limit.
3493 if ((!ext4_ext_is_unwritten(abut_ex
)) && /*C1*/
3494 ((map
->m_lblk
+ map_len
) == next_lblk
) && /*C2*/
3495 ((ee_pblk
+ ee_len
) == next_pblk
) && /*C3*/
3496 (next_len
< (EXT_INIT_MAX_LEN
- map_len
))) { /*C4*/
3497 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3501 trace_ext4_ext_convert_to_initialized_fastpath(inode
,
3504 /* Shift the start of abut_ex by 'map_len' blocks */
3505 abut_ex
->ee_block
= cpu_to_le32(next_lblk
- map_len
);
3506 ext4_ext_store_pblock(abut_ex
, next_pblk
- map_len
);
3507 ex
->ee_len
= cpu_to_le16(ee_len
- map_len
);
3508 ext4_ext_mark_unwritten(ex
); /* Restore the flag */
3510 /* Extend abut_ex by 'map_len' blocks */
3511 abut_ex
->ee_len
= cpu_to_le16(next_len
+ map_len
);
3513 /* Result: number of initialized blocks past m_lblk */
3514 allocated
= map_len
;
3518 /* Mark the block containing both extents as dirty */
3519 ext4_ext_dirty(handle
, inode
, path
+ depth
);
3521 /* Update path to point to the right extent */
3522 path
[depth
].p_ext
= abut_ex
;
3525 allocated
= ee_len
- (map
->m_lblk
- ee_block
);
3527 WARN_ON(map
->m_lblk
< ee_block
);
3529 * It is safe to convert extent to initialized via explicit
3530 * zeroout only if extent is fully inside i_size or new_size.
3532 split_flag
|= ee_block
+ ee_len
<= eof_block
? EXT4_EXT_MAY_ZEROOUT
: 0;
3534 if (EXT4_EXT_MAY_ZEROOUT
& split_flag
)
3535 max_zeroout
= sbi
->s_extent_max_zeroout_kb
>>
3536 (inode
->i_sb
->s_blocksize_bits
- 10);
3538 /* If extent is less than s_max_zeroout_kb, zeroout directly */
3539 if (max_zeroout
&& (ee_len
<= max_zeroout
)) {
3540 err
= ext4_ext_zeroout(inode
, ex
);
3543 zero_ex
.ee_block
= ex
->ee_block
;
3544 zero_ex
.ee_len
= cpu_to_le16(ext4_ext_get_actual_len(ex
));
3545 ext4_ext_store_pblock(&zero_ex
, ext4_ext_pblock(ex
));
3547 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3550 ext4_ext_mark_initialized(ex
);
3551 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3552 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3558 * 1. split the extent into three extents.
3559 * 2. split the extent into two extents, zeroout the first half.
3560 * 3. split the extent into two extents, zeroout the second half.
3561 * 4. split the extent into two extents with out zeroout.
3563 split_map
.m_lblk
= map
->m_lblk
;
3564 split_map
.m_len
= map
->m_len
;
3566 if (max_zeroout
&& (allocated
> map
->m_len
)) {
3567 if (allocated
<= max_zeroout
) {
3570 cpu_to_le32(map
->m_lblk
);
3571 zero_ex
.ee_len
= cpu_to_le16(allocated
);
3572 ext4_ext_store_pblock(&zero_ex
,
3573 ext4_ext_pblock(ex
) + map
->m_lblk
- ee_block
);
3574 err
= ext4_ext_zeroout(inode
, &zero_ex
);
3577 split_map
.m_lblk
= map
->m_lblk
;
3578 split_map
.m_len
= allocated
;
3579 } else if (map
->m_lblk
- ee_block
+ map
->m_len
< max_zeroout
) {
3581 if (map
->m_lblk
!= ee_block
) {
3582 zero_ex
.ee_block
= ex
->ee_block
;
3583 zero_ex
.ee_len
= cpu_to_le16(map
->m_lblk
-
3585 ext4_ext_store_pblock(&zero_ex
,
3586 ext4_ext_pblock(ex
));
3587 err
= ext4_ext_zeroout(inode
, &zero_ex
);
3592 split_map
.m_lblk
= ee_block
;
3593 split_map
.m_len
= map
->m_lblk
- ee_block
+ map
->m_len
;
3594 allocated
= map
->m_len
;
3598 allocated
= ext4_split_extent(handle
, inode
, ppath
,
3599 &split_map
, split_flag
, flags
);
3604 /* If we have gotten a failure, don't zero out status tree */
3606 err
= ext4_zeroout_es(inode
, &zero_ex
);
3607 return err
? err
: allocated
;
3611 * This function is called by ext4_ext_map_blocks() from
3612 * ext4_get_blocks_dio_write() when DIO to write
3613 * to an unwritten extent.
3615 * Writing to an unwritten extent may result in splitting the unwritten
3616 * extent into multiple initialized/unwritten extents (up to three)
3617 * There are three possibilities:
3618 * a> There is no split required: Entire extent should be unwritten
3619 * b> Splits in two extents: Write is happening at either end of the extent
3620 * c> Splits in three extents: Somone is writing in middle of the extent
3622 * This works the same way in the case of initialized -> unwritten conversion.
3624 * One of more index blocks maybe needed if the extent tree grow after
3625 * the unwritten extent split. To prevent ENOSPC occur at the IO
3626 * complete, we need to split the unwritten extent before DIO submit
3627 * the IO. The unwritten extent called at this time will be split
3628 * into three unwritten extent(at most). After IO complete, the part
3629 * being filled will be convert to initialized by the end_io callback function
3630 * via ext4_convert_unwritten_extents().
3632 * Returns the size of unwritten extent to be written on success.
3634 static int ext4_split_convert_extents(handle_t
*handle
,
3635 struct inode
*inode
,
3636 struct ext4_map_blocks
*map
,
3637 struct ext4_ext_path
**ppath
,
3640 struct ext4_ext_path
*path
= *ppath
;
3641 ext4_lblk_t eof_block
;
3642 ext4_lblk_t ee_block
;
3643 struct ext4_extent
*ex
;
3644 unsigned int ee_len
;
3645 int split_flag
= 0, depth
;
3647 ext_debug("%s: inode %lu, logical block %llu, max_blocks %u\n",
3648 __func__
, inode
->i_ino
,
3649 (unsigned long long)map
->m_lblk
, map
->m_len
);
3651 eof_block
= (inode
->i_size
+ inode
->i_sb
->s_blocksize
- 1) >>
3652 inode
->i_sb
->s_blocksize_bits
;
3653 if (eof_block
< map
->m_lblk
+ map
->m_len
)
3654 eof_block
= map
->m_lblk
+ map
->m_len
;
3656 * It is safe to convert extent to initialized via explicit
3657 * zeroout only if extent is fully insde i_size or new_size.
3659 depth
= ext_depth(inode
);
3660 ex
= path
[depth
].p_ext
;
3661 ee_block
= le32_to_cpu(ex
->ee_block
);
3662 ee_len
= ext4_ext_get_actual_len(ex
);
3664 /* Convert to unwritten */
3665 if (flags
& EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
) {
3666 split_flag
|= EXT4_EXT_DATA_VALID1
;
3667 /* Convert to initialized */
3668 } else if (flags
& EXT4_GET_BLOCKS_CONVERT
) {
3669 split_flag
|= ee_block
+ ee_len
<= eof_block
?
3670 EXT4_EXT_MAY_ZEROOUT
: 0;
3671 split_flag
|= (EXT4_EXT_MARK_UNWRIT2
| EXT4_EXT_DATA_VALID2
);
3673 flags
|= EXT4_GET_BLOCKS_PRE_IO
;
3674 return ext4_split_extent(handle
, inode
, ppath
, map
, split_flag
, flags
);
3677 static int ext4_convert_unwritten_extents_endio(handle_t
*handle
,
3678 struct inode
*inode
,
3679 struct ext4_map_blocks
*map
,
3680 struct ext4_ext_path
**ppath
)
3682 struct ext4_ext_path
*path
= *ppath
;
3683 struct ext4_extent
*ex
;
3684 ext4_lblk_t ee_block
;
3685 unsigned int ee_len
;
3689 depth
= ext_depth(inode
);
3690 ex
= path
[depth
].p_ext
;
3691 ee_block
= le32_to_cpu(ex
->ee_block
);
3692 ee_len
= ext4_ext_get_actual_len(ex
);
3694 ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical"
3695 "block %llu, max_blocks %u\n", inode
->i_ino
,
3696 (unsigned long long)ee_block
, ee_len
);
3698 /* If extent is larger than requested it is a clear sign that we still
3699 * have some extent state machine issues left. So extent_split is still
3701 * TODO: Once all related issues will be fixed this situation should be
3704 if (ee_block
!= map
->m_lblk
|| ee_len
> map
->m_len
) {
3706 ext4_warning("Inode (%ld) finished: extent logical block %llu,"
3707 " len %u; IO logical block %llu, len %u\n",
3708 inode
->i_ino
, (unsigned long long)ee_block
, ee_len
,
3709 (unsigned long long)map
->m_lblk
, map
->m_len
);
3711 err
= ext4_split_convert_extents(handle
, inode
, map
, ppath
,
3712 EXT4_GET_BLOCKS_CONVERT
);
3715 path
= ext4_ext_find_extent(inode
, map
->m_lblk
, ppath
, 0);
3717 return PTR_ERR(path
);
3718 depth
= ext_depth(inode
);
3719 ex
= path
[depth
].p_ext
;
3722 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3725 /* first mark the extent as initialized */
3726 ext4_ext_mark_initialized(ex
);
3728 /* note: ext4_ext_correct_indexes() isn't needed here because
3729 * borders are not changed
3731 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3733 /* Mark modified extent as dirty */
3734 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3736 ext4_ext_show_leaf(inode
, path
);
3740 static void unmap_underlying_metadata_blocks(struct block_device
*bdev
,
3741 sector_t block
, int count
)
3744 for (i
= 0; i
< count
; i
++)
3745 unmap_underlying_metadata(bdev
, block
+ i
);
3749 * Handle EOFBLOCKS_FL flag, clearing it if necessary
3751 static int check_eofblocks_fl(handle_t
*handle
, struct inode
*inode
,
3753 struct ext4_ext_path
*path
,
3757 struct ext4_extent_header
*eh
;
3758 struct ext4_extent
*last_ex
;
3760 if (!ext4_test_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
))
3763 depth
= ext_depth(inode
);
3764 eh
= path
[depth
].p_hdr
;
3767 * We're going to remove EOFBLOCKS_FL entirely in future so we
3768 * do not care for this case anymore. Simply remove the flag
3769 * if there are no extents.
3771 if (unlikely(!eh
->eh_entries
))
3773 last_ex
= EXT_LAST_EXTENT(eh
);
3775 * We should clear the EOFBLOCKS_FL flag if we are writing the
3776 * last block in the last extent in the file. We test this by
3777 * first checking to see if the caller to
3778 * ext4_ext_get_blocks() was interested in the last block (or
3779 * a block beyond the last block) in the current extent. If
3780 * this turns out to be false, we can bail out from this
3781 * function immediately.
3783 if (lblk
+ len
< le32_to_cpu(last_ex
->ee_block
) +
3784 ext4_ext_get_actual_len(last_ex
))
3787 * If the caller does appear to be planning to write at or
3788 * beyond the end of the current extent, we then test to see
3789 * if the current extent is the last extent in the file, by
3790 * checking to make sure it was reached via the rightmost node
3791 * at each level of the tree.
3793 for (i
= depth
-1; i
>= 0; i
--)
3794 if (path
[i
].p_idx
!= EXT_LAST_INDEX(path
[i
].p_hdr
))
3797 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3798 return ext4_mark_inode_dirty(handle
, inode
);
3802 * ext4_find_delalloc_range: find delayed allocated block in the given range.
3804 * Return 1 if there is a delalloc block in the range, otherwise 0.
3806 int ext4_find_delalloc_range(struct inode
*inode
,
3807 ext4_lblk_t lblk_start
,
3808 ext4_lblk_t lblk_end
)
3810 struct extent_status es
;
3812 ext4_es_find_delayed_extent_range(inode
, lblk_start
, lblk_end
, &es
);
3814 return 0; /* there is no delay extent in this tree */
3815 else if (es
.es_lblk
<= lblk_start
&&
3816 lblk_start
< es
.es_lblk
+ es
.es_len
)
3818 else if (lblk_start
<= es
.es_lblk
&& es
.es_lblk
<= lblk_end
)
3824 int ext4_find_delalloc_cluster(struct inode
*inode
, ext4_lblk_t lblk
)
3826 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
3827 ext4_lblk_t lblk_start
, lblk_end
;
3828 lblk_start
= EXT4_LBLK_CMASK(sbi
, lblk
);
3829 lblk_end
= lblk_start
+ sbi
->s_cluster_ratio
- 1;
3831 return ext4_find_delalloc_range(inode
, lblk_start
, lblk_end
);
3835 * Determines how many complete clusters (out of those specified by the 'map')
3836 * are under delalloc and were reserved quota for.
3837 * This function is called when we are writing out the blocks that were
3838 * originally written with their allocation delayed, but then the space was
3839 * allocated using fallocate() before the delayed allocation could be resolved.
3840 * The cases to look for are:
3841 * ('=' indicated delayed allocated blocks
3842 * '-' indicates non-delayed allocated blocks)
3843 * (a) partial clusters towards beginning and/or end outside of allocated range
3844 * are not delalloc'ed.
3846 * |----c---=|====c====|====c====|===-c----|
3847 * |++++++ allocated ++++++|
3848 * ==> 4 complete clusters in above example
3850 * (b) partial cluster (outside of allocated range) towards either end is
3851 * marked for delayed allocation. In this case, we will exclude that
3854 * |----====c========|========c========|
3855 * |++++++ allocated ++++++|
3856 * ==> 1 complete clusters in above example
3859 * |================c================|
3860 * |++++++ allocated ++++++|
3861 * ==> 0 complete clusters in above example
3863 * The ext4_da_update_reserve_space will be called only if we
3864 * determine here that there were some "entire" clusters that span
3865 * this 'allocated' range.
3866 * In the non-bigalloc case, this function will just end up returning num_blks
3867 * without ever calling ext4_find_delalloc_range.
3870 get_reserved_cluster_alloc(struct inode
*inode
, ext4_lblk_t lblk_start
,
3871 unsigned int num_blks
)
3873 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
3874 ext4_lblk_t alloc_cluster_start
, alloc_cluster_end
;
3875 ext4_lblk_t lblk_from
, lblk_to
, c_offset
;
3876 unsigned int allocated_clusters
= 0;
3878 alloc_cluster_start
= EXT4_B2C(sbi
, lblk_start
);
3879 alloc_cluster_end
= EXT4_B2C(sbi
, lblk_start
+ num_blks
- 1);
3881 /* max possible clusters for this allocation */
3882 allocated_clusters
= alloc_cluster_end
- alloc_cluster_start
+ 1;
3884 trace_ext4_get_reserved_cluster_alloc(inode
, lblk_start
, num_blks
);
3886 /* Check towards left side */
3887 c_offset
= EXT4_LBLK_COFF(sbi
, lblk_start
);
3889 lblk_from
= EXT4_LBLK_CMASK(sbi
, lblk_start
);
3890 lblk_to
= lblk_from
+ c_offset
- 1;
3892 if (ext4_find_delalloc_range(inode
, lblk_from
, lblk_to
))
3893 allocated_clusters
--;
3896 /* Now check towards right. */
3897 c_offset
= EXT4_LBLK_COFF(sbi
, lblk_start
+ num_blks
);
3898 if (allocated_clusters
&& c_offset
) {
3899 lblk_from
= lblk_start
+ num_blks
;
3900 lblk_to
= lblk_from
+ (sbi
->s_cluster_ratio
- c_offset
) - 1;
3902 if (ext4_find_delalloc_range(inode
, lblk_from
, lblk_to
))
3903 allocated_clusters
--;
3906 return allocated_clusters
;
3910 convert_initialized_extent(handle_t
*handle
, struct inode
*inode
,
3911 struct ext4_map_blocks
*map
,
3912 struct ext4_ext_path
**ppath
, int flags
,
3913 unsigned int allocated
, ext4_fsblk_t newblock
)
3915 struct ext4_ext_path
*path
= *ppath
;
3916 struct ext4_extent
*ex
;
3917 ext4_lblk_t ee_block
;
3918 unsigned int ee_len
;
3923 * Make sure that the extent is no bigger than we support with
3926 if (map
->m_len
> EXT_UNWRITTEN_MAX_LEN
)
3927 map
->m_len
= EXT_UNWRITTEN_MAX_LEN
/ 2;
3929 depth
= ext_depth(inode
);
3930 ex
= path
[depth
].p_ext
;
3931 ee_block
= le32_to_cpu(ex
->ee_block
);
3932 ee_len
= ext4_ext_get_actual_len(ex
);
3934 ext_debug("%s: inode %lu, logical"
3935 "block %llu, max_blocks %u\n", __func__
, inode
->i_ino
,
3936 (unsigned long long)ee_block
, ee_len
);
3938 if (ee_block
!= map
->m_lblk
|| ee_len
> map
->m_len
) {
3939 err
= ext4_split_convert_extents(handle
, inode
, map
, ppath
,
3940 EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
);
3943 path
= ext4_ext_find_extent(inode
, map
->m_lblk
, ppath
, 0);
3945 return PTR_ERR(path
);
3946 depth
= ext_depth(inode
);
3947 ex
= path
[depth
].p_ext
;
3949 EXT4_ERROR_INODE(inode
, "unexpected hole at %lu",
3950 (unsigned long) map
->m_lblk
);
3955 err
= ext4_ext_get_access(handle
, inode
, path
+ depth
);
3958 /* first mark the extent as unwritten */
3959 ext4_ext_mark_unwritten(ex
);
3961 /* note: ext4_ext_correct_indexes() isn't needed here because
3962 * borders are not changed
3964 ext4_ext_try_to_merge(handle
, inode
, path
, ex
);
3966 /* Mark modified extent as dirty */
3967 err
= ext4_ext_dirty(handle
, inode
, path
+ path
->p_depth
);
3970 ext4_ext_show_leaf(inode
, path
);
3972 ext4_update_inode_fsync_trans(handle
, inode
, 1);
3973 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
, path
, map
->m_len
);
3976 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
3977 if (allocated
> map
->m_len
)
3978 allocated
= map
->m_len
;
3979 map
->m_len
= allocated
;
3984 ext4_ext_handle_unwritten_extents(handle_t
*handle
, struct inode
*inode
,
3985 struct ext4_map_blocks
*map
,
3986 struct ext4_ext_path
**ppath
, int flags
,
3987 unsigned int allocated
, ext4_fsblk_t newblock
)
3989 struct ext4_ext_path
*path
= *ppath
;
3992 ext4_io_end_t
*io
= ext4_inode_aio(inode
);
3994 ext_debug("ext4_ext_handle_unwritten_extents: inode %lu, logical "
3995 "block %llu, max_blocks %u, flags %x, allocated %u\n",
3996 inode
->i_ino
, (unsigned long long)map
->m_lblk
, map
->m_len
,
3998 ext4_ext_show_leaf(inode
, path
);
4001 * When writing into unwritten space, we should not fail to
4002 * allocate metadata blocks for the new extent block if needed.
4004 flags
|= EXT4_GET_BLOCKS_METADATA_NOFAIL
;
4006 trace_ext4_ext_handle_unwritten_extents(inode
, map
, flags
,
4007 allocated
, newblock
);
4009 /* get_block() before submit the IO, split the extent */
4010 if (flags
& EXT4_GET_BLOCKS_PRE_IO
) {
4011 ret
= ext4_split_convert_extents(handle
, inode
, map
, ppath
,
4012 flags
| EXT4_GET_BLOCKS_CONVERT
);
4016 * Flag the inode(non aio case) or end_io struct (aio case)
4017 * that this IO needs to conversion to written when IO is
4021 ext4_set_io_unwritten_flag(inode
, io
);
4023 ext4_set_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
4024 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
4027 /* IO end_io complete, convert the filled extent to written */
4028 if (flags
& EXT4_GET_BLOCKS_CONVERT
) {
4029 ret
= ext4_convert_unwritten_extents_endio(handle
, inode
, map
,
4032 ext4_update_inode_fsync_trans(handle
, inode
, 1);
4033 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
,
4037 map
->m_flags
|= EXT4_MAP_MAPPED
;
4038 map
->m_pblk
= newblock
;
4039 if (allocated
> map
->m_len
)
4040 allocated
= map
->m_len
;
4041 map
->m_len
= allocated
;
4044 /* buffered IO case */
4046 * repeat fallocate creation request
4047 * we already have an unwritten extent
4049 if (flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
) {
4050 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
4054 /* buffered READ or buffered write_begin() lookup */
4055 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
4057 * We have blocks reserved already. We
4058 * return allocated blocks so that delalloc
4059 * won't do block reservation for us. But
4060 * the buffer head will be unmapped so that
4061 * a read from the block returns 0s.
4063 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
4067 /* buffered write, writepage time, convert*/
4068 ret
= ext4_ext_convert_to_initialized(handle
, inode
, map
, ppath
, flags
);
4070 ext4_update_inode_fsync_trans(handle
, inode
, 1);
4077 map
->m_flags
|= EXT4_MAP_NEW
;
4079 * if we allocated more blocks than requested
4080 * we need to make sure we unmap the extra block
4081 * allocated. The actual needed block will get
4082 * unmapped later when we find the buffer_head marked
4085 if (allocated
> map
->m_len
) {
4086 unmap_underlying_metadata_blocks(inode
->i_sb
->s_bdev
,
4087 newblock
+ map
->m_len
,
4088 allocated
- map
->m_len
);
4089 allocated
= map
->m_len
;
4091 map
->m_len
= allocated
;
4094 * If we have done fallocate with the offset that is already
4095 * delayed allocated, we would have block reservation
4096 * and quota reservation done in the delayed write path.
4097 * But fallocate would have already updated quota and block
4098 * count for this offset. So cancel these reservation
4100 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) {
4101 unsigned int reserved_clusters
;
4102 reserved_clusters
= get_reserved_cluster_alloc(inode
,
4103 map
->m_lblk
, map
->m_len
);
4104 if (reserved_clusters
)
4105 ext4_da_update_reserve_space(inode
,
4111 map
->m_flags
|= EXT4_MAP_MAPPED
;
4112 if ((flags
& EXT4_GET_BLOCKS_KEEP_SIZE
) == 0) {
4113 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
, path
,
4119 if (allocated
> map
->m_len
)
4120 allocated
= map
->m_len
;
4121 ext4_ext_show_leaf(inode
, path
);
4122 map
->m_pblk
= newblock
;
4123 map
->m_len
= allocated
;
4125 return err
? err
: allocated
;
4129 * get_implied_cluster_alloc - check to see if the requested
4130 * allocation (in the map structure) overlaps with a cluster already
4131 * allocated in an extent.
4132 * @sb The filesystem superblock structure
4133 * @map The requested lblk->pblk mapping
4134 * @ex The extent structure which might contain an implied
4135 * cluster allocation
4137 * This function is called by ext4_ext_map_blocks() after we failed to
4138 * find blocks that were already in the inode's extent tree. Hence,
4139 * we know that the beginning of the requested region cannot overlap
4140 * the extent from the inode's extent tree. There are three cases we
4141 * want to catch. The first is this case:
4143 * |--- cluster # N--|
4144 * |--- extent ---| |---- requested region ---|
4147 * The second case that we need to test for is this one:
4149 * |--------- cluster # N ----------------|
4150 * |--- requested region --| |------- extent ----|
4151 * |=======================|
4153 * The third case is when the requested region lies between two extents
4154 * within the same cluster:
4155 * |------------- cluster # N-------------|
4156 * |----- ex -----| |---- ex_right ----|
4157 * |------ requested region ------|
4158 * |================|
4160 * In each of the above cases, we need to set the map->m_pblk and
4161 * map->m_len so it corresponds to the return the extent labelled as
4162 * "|====|" from cluster #N, since it is already in use for data in
4163 * cluster EXT4_B2C(sbi, map->m_lblk). We will then return 1 to
4164 * signal to ext4_ext_map_blocks() that map->m_pblk should be treated
4165 * as a new "allocated" block region. Otherwise, we will return 0 and
4166 * ext4_ext_map_blocks() will then allocate one or more new clusters
4167 * by calling ext4_mb_new_blocks().
4169 static int get_implied_cluster_alloc(struct super_block
*sb
,
4170 struct ext4_map_blocks
*map
,
4171 struct ext4_extent
*ex
,
4172 struct ext4_ext_path
*path
)
4174 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
4175 ext4_lblk_t c_offset
= EXT4_LBLK_COFF(sbi
, map
->m_lblk
);
4176 ext4_lblk_t ex_cluster_start
, ex_cluster_end
;
4177 ext4_lblk_t rr_cluster_start
;
4178 ext4_lblk_t ee_block
= le32_to_cpu(ex
->ee_block
);
4179 ext4_fsblk_t ee_start
= ext4_ext_pblock(ex
);
4180 unsigned short ee_len
= ext4_ext_get_actual_len(ex
);
4182 /* The extent passed in that we are trying to match */
4183 ex_cluster_start
= EXT4_B2C(sbi
, ee_block
);
4184 ex_cluster_end
= EXT4_B2C(sbi
, ee_block
+ ee_len
- 1);
4186 /* The requested region passed into ext4_map_blocks() */
4187 rr_cluster_start
= EXT4_B2C(sbi
, map
->m_lblk
);
4189 if ((rr_cluster_start
== ex_cluster_end
) ||
4190 (rr_cluster_start
== ex_cluster_start
)) {
4191 if (rr_cluster_start
== ex_cluster_end
)
4192 ee_start
+= ee_len
- 1;
4193 map
->m_pblk
= EXT4_PBLK_CMASK(sbi
, ee_start
) + c_offset
;
4194 map
->m_len
= min(map
->m_len
,
4195 (unsigned) sbi
->s_cluster_ratio
- c_offset
);
4197 * Check for and handle this case:
4199 * |--------- cluster # N-------------|
4200 * |------- extent ----|
4201 * |--- requested region ---|
4205 if (map
->m_lblk
< ee_block
)
4206 map
->m_len
= min(map
->m_len
, ee_block
- map
->m_lblk
);
4209 * Check for the case where there is already another allocated
4210 * block to the right of 'ex' but before the end of the cluster.
4212 * |------------- cluster # N-------------|
4213 * |----- ex -----| |---- ex_right ----|
4214 * |------ requested region ------|
4215 * |================|
4217 if (map
->m_lblk
> ee_block
) {
4218 ext4_lblk_t next
= ext4_ext_next_allocated_block(path
);
4219 map
->m_len
= min(map
->m_len
, next
- map
->m_lblk
);
4222 trace_ext4_get_implied_cluster_alloc_exit(sb
, map
, 1);
4226 trace_ext4_get_implied_cluster_alloc_exit(sb
, map
, 0);
4232 * Block allocation/map/preallocation routine for extents based files
4235 * Need to be called with
4236 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
4237 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
4239 * return > 0, number of of blocks already mapped/allocated
4240 * if create == 0 and these are pre-allocated blocks
4241 * buffer head is unmapped
4242 * otherwise blocks are mapped
4244 * return = 0, if plain look up failed (blocks have not been allocated)
4245 * buffer head is unmapped
4247 * return < 0, error case.
4249 int ext4_ext_map_blocks(handle_t
*handle
, struct inode
*inode
,
4250 struct ext4_map_blocks
*map
, int flags
)
4252 struct ext4_ext_path
*path
= NULL
;
4253 struct ext4_extent newex
, *ex
, *ex2
;
4254 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4255 ext4_fsblk_t newblock
= 0;
4256 int free_on_err
= 0, err
= 0, depth
, ret
;
4257 unsigned int allocated
= 0, offset
= 0;
4258 unsigned int allocated_clusters
= 0;
4259 struct ext4_allocation_request ar
;
4260 ext4_io_end_t
*io
= ext4_inode_aio(inode
);
4261 ext4_lblk_t cluster_offset
;
4262 int set_unwritten
= 0;
4264 ext_debug("blocks %u/%u requested for inode %lu\n",
4265 map
->m_lblk
, map
->m_len
, inode
->i_ino
);
4266 trace_ext4_ext_map_blocks_enter(inode
, map
->m_lblk
, map
->m_len
, flags
);
4268 /* find extent for this block */
4269 path
= ext4_ext_find_extent(inode
, map
->m_lblk
, NULL
, 0);
4271 err
= PTR_ERR(path
);
4276 depth
= ext_depth(inode
);
4279 * consistent leaf must not be empty;
4280 * this situation is possible, though, _during_ tree modification;
4281 * this is why assert can't be put in ext4_ext_find_extent()
4283 if (unlikely(path
[depth
].p_ext
== NULL
&& depth
!= 0)) {
4284 EXT4_ERROR_INODE(inode
, "bad extent address "
4285 "lblock: %lu, depth: %d pblock %lld",
4286 (unsigned long) map
->m_lblk
, depth
,
4287 path
[depth
].p_block
);
4292 ex
= path
[depth
].p_ext
;
4294 ext4_lblk_t ee_block
= le32_to_cpu(ex
->ee_block
);
4295 ext4_fsblk_t ee_start
= ext4_ext_pblock(ex
);
4296 unsigned short ee_len
;
4300 * unwritten extents are treated as holes, except that
4301 * we split out initialized portions during a write.
4303 ee_len
= ext4_ext_get_actual_len(ex
);
4305 trace_ext4_ext_show_extent(inode
, ee_block
, ee_start
, ee_len
);
4307 /* if found extent covers block, simply return it */
4308 if (in_range(map
->m_lblk
, ee_block
, ee_len
)) {
4309 newblock
= map
->m_lblk
- ee_block
+ ee_start
;
4310 /* number of remaining blocks in the extent */
4311 allocated
= ee_len
- (map
->m_lblk
- ee_block
);
4312 ext_debug("%u fit into %u:%d -> %llu\n", map
->m_lblk
,
4313 ee_block
, ee_len
, newblock
);
4316 * If the extent is initialized check whether the
4317 * caller wants to convert it to unwritten.
4319 if ((!ext4_ext_is_unwritten(ex
)) &&
4320 (flags
& EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
)) {
4321 allocated
= convert_initialized_extent(
4322 handle
, inode
, map
, &path
,
4323 flags
, allocated
, newblock
);
4325 } else if (!ext4_ext_is_unwritten(ex
))
4328 ret
= ext4_ext_handle_unwritten_extents(
4329 handle
, inode
, map
, &path
, flags
,
4330 allocated
, newblock
);
4339 if ((sbi
->s_cluster_ratio
> 1) &&
4340 ext4_find_delalloc_cluster(inode
, map
->m_lblk
))
4341 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
4344 * requested block isn't allocated yet;
4345 * we couldn't try to create block if create flag is zero
4347 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0) {
4349 * put just found gap into cache to speed up
4350 * subsequent requests
4352 if ((flags
& EXT4_GET_BLOCKS_NO_PUT_HOLE
) == 0)
4353 ext4_ext_put_gap_in_cache(inode
, path
, map
->m_lblk
);
4358 * Okay, we need to do block allocation.
4360 map
->m_flags
&= ~EXT4_MAP_FROM_CLUSTER
;
4361 newex
.ee_block
= cpu_to_le32(map
->m_lblk
);
4362 cluster_offset
= EXT4_LBLK_COFF(sbi
, map
->m_lblk
);
4365 * If we are doing bigalloc, check to see if the extent returned
4366 * by ext4_ext_find_extent() implies a cluster we can use.
4368 if (cluster_offset
&& ex
&&
4369 get_implied_cluster_alloc(inode
->i_sb
, map
, ex
, path
)) {
4370 ar
.len
= allocated
= map
->m_len
;
4371 newblock
= map
->m_pblk
;
4372 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
4373 goto got_allocated_blocks
;
4376 /* find neighbour allocated blocks */
4377 ar
.lleft
= map
->m_lblk
;
4378 err
= ext4_ext_search_left(inode
, path
, &ar
.lleft
, &ar
.pleft
);
4381 ar
.lright
= map
->m_lblk
;
4383 err
= ext4_ext_search_right(inode
, path
, &ar
.lright
, &ar
.pright
, &ex2
);
4387 /* Check if the extent after searching to the right implies a
4388 * cluster we can use. */
4389 if ((sbi
->s_cluster_ratio
> 1) && ex2
&&
4390 get_implied_cluster_alloc(inode
->i_sb
, map
, ex2
, path
)) {
4391 ar
.len
= allocated
= map
->m_len
;
4392 newblock
= map
->m_pblk
;
4393 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
4394 goto got_allocated_blocks
;
4398 * See if request is beyond maximum number of blocks we can have in
4399 * a single extent. For an initialized extent this limit is
4400 * EXT_INIT_MAX_LEN and for an unwritten extent this limit is
4401 * EXT_UNWRITTEN_MAX_LEN.
4403 if (map
->m_len
> EXT_INIT_MAX_LEN
&&
4404 !(flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
))
4405 map
->m_len
= EXT_INIT_MAX_LEN
;
4406 else if (map
->m_len
> EXT_UNWRITTEN_MAX_LEN
&&
4407 (flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
))
4408 map
->m_len
= EXT_UNWRITTEN_MAX_LEN
;
4410 /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
4411 newex
.ee_len
= cpu_to_le16(map
->m_len
);
4412 err
= ext4_ext_check_overlap(sbi
, inode
, &newex
, path
);
4414 allocated
= ext4_ext_get_actual_len(&newex
);
4416 allocated
= map
->m_len
;
4418 /* allocate new block */
4420 ar
.goal
= ext4_ext_find_goal(inode
, path
, map
->m_lblk
);
4421 ar
.logical
= map
->m_lblk
;
4423 * We calculate the offset from the beginning of the cluster
4424 * for the logical block number, since when we allocate a
4425 * physical cluster, the physical block should start at the
4426 * same offset from the beginning of the cluster. This is
4427 * needed so that future calls to get_implied_cluster_alloc()
4430 offset
= EXT4_LBLK_COFF(sbi
, map
->m_lblk
);
4431 ar
.len
= EXT4_NUM_B2C(sbi
, offset
+allocated
);
4433 ar
.logical
-= offset
;
4434 if (S_ISREG(inode
->i_mode
))
4435 ar
.flags
= EXT4_MB_HINT_DATA
;
4437 /* disable in-core preallocation for non-regular files */
4439 if (flags
& EXT4_GET_BLOCKS_NO_NORMALIZE
)
4440 ar
.flags
|= EXT4_MB_HINT_NOPREALLOC
;
4441 newblock
= ext4_mb_new_blocks(handle
, &ar
, &err
);
4444 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
4445 ar
.goal
, newblock
, allocated
);
4447 allocated_clusters
= ar
.len
;
4448 ar
.len
= EXT4_C2B(sbi
, ar
.len
) - offset
;
4449 if (ar
.len
> allocated
)
4452 got_allocated_blocks
:
4453 /* try to insert new extent into found leaf and return */
4454 ext4_ext_store_pblock(&newex
, newblock
+ offset
);
4455 newex
.ee_len
= cpu_to_le16(ar
.len
);
4456 /* Mark unwritten */
4457 if (flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
){
4458 ext4_ext_mark_unwritten(&newex
);
4459 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
4461 * io_end structure was created for every IO write to an
4462 * unwritten extent. To avoid unnecessary conversion,
4463 * here we flag the IO that really needs the conversion.
4464 * For non asycn direct IO case, flag the inode state
4465 * that we need to perform conversion when IO is done.
4467 if (flags
& EXT4_GET_BLOCKS_PRE_IO
)
4472 if ((flags
& EXT4_GET_BLOCKS_KEEP_SIZE
) == 0)
4473 err
= check_eofblocks_fl(handle
, inode
, map
->m_lblk
,
4476 err
= ext4_ext_insert_extent(handle
, inode
, &path
,
4479 if (!err
&& set_unwritten
) {
4481 ext4_set_io_unwritten_flag(inode
, io
);
4483 ext4_set_inode_state(inode
,
4484 EXT4_STATE_DIO_UNWRITTEN
);
4487 if (err
&& free_on_err
) {
4488 int fb_flags
= flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
?
4489 EXT4_FREE_BLOCKS_NO_QUOT_UPDATE
: 0;
4490 /* free data blocks we just allocated */
4491 /* not a good idea to call discard here directly,
4492 * but otherwise we'd need to call it every free() */
4493 ext4_discard_preallocations(inode
);
4494 ext4_free_blocks(handle
, inode
, NULL
, newblock
,
4495 EXT4_C2B(sbi
, allocated_clusters
), fb_flags
);
4499 /* previous routine could use block we allocated */
4500 newblock
= ext4_ext_pblock(&newex
);
4501 allocated
= ext4_ext_get_actual_len(&newex
);
4502 if (allocated
> map
->m_len
)
4503 allocated
= map
->m_len
;
4504 map
->m_flags
|= EXT4_MAP_NEW
;
4507 * Update reserved blocks/metadata blocks after successful
4508 * block allocation which had been deferred till now.
4510 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) {
4511 unsigned int reserved_clusters
;
4513 * Check how many clusters we had reserved this allocated range
4515 reserved_clusters
= get_reserved_cluster_alloc(inode
,
4516 map
->m_lblk
, allocated
);
4517 if (map
->m_flags
& EXT4_MAP_FROM_CLUSTER
) {
4518 if (reserved_clusters
) {
4520 * We have clusters reserved for this range.
4521 * But since we are not doing actual allocation
4522 * and are simply using blocks from previously
4523 * allocated cluster, we should release the
4524 * reservation and not claim quota.
4526 ext4_da_update_reserve_space(inode
,
4527 reserved_clusters
, 0);
4530 BUG_ON(allocated_clusters
< reserved_clusters
);
4531 if (reserved_clusters
< allocated_clusters
) {
4532 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4533 int reservation
= allocated_clusters
-
4536 * It seems we claimed few clusters outside of
4537 * the range of this allocation. We should give
4538 * it back to the reservation pool. This can
4539 * happen in the following case:
4541 * * Suppose s_cluster_ratio is 4 (i.e., each
4542 * cluster has 4 blocks. Thus, the clusters
4543 * are [0-3],[4-7],[8-11]...
4544 * * First comes delayed allocation write for
4545 * logical blocks 10 & 11. Since there were no
4546 * previous delayed allocated blocks in the
4547 * range [8-11], we would reserve 1 cluster
4549 * * Next comes write for logical blocks 3 to 8.
4550 * In this case, we will reserve 2 clusters
4551 * (for [0-3] and [4-7]; and not for [8-11] as
4552 * that range has a delayed allocated blocks.
4553 * Thus total reserved clusters now becomes 3.
4554 * * Now, during the delayed allocation writeout
4555 * time, we will first write blocks [3-8] and
4556 * allocate 3 clusters for writing these
4557 * blocks. Also, we would claim all these
4558 * three clusters above.
4559 * * Now when we come here to writeout the
4560 * blocks [10-11], we would expect to claim
4561 * the reservation of 1 cluster we had made
4562 * (and we would claim it since there are no
4563 * more delayed allocated blocks in the range
4564 * [8-11]. But our reserved cluster count had
4565 * already gone to 0.
4567 * Thus, at the step 4 above when we determine
4568 * that there are still some unwritten delayed
4569 * allocated blocks outside of our current
4570 * block range, we should increment the
4571 * reserved clusters count so that when the
4572 * remaining blocks finally gets written, we
4575 dquot_reserve_block(inode
,
4576 EXT4_C2B(sbi
, reservation
));
4577 spin_lock(&ei
->i_block_reservation_lock
);
4578 ei
->i_reserved_data_blocks
+= reservation
;
4579 spin_unlock(&ei
->i_block_reservation_lock
);
4582 * We will claim quota for all newly allocated blocks.
4583 * We're updating the reserved space *after* the
4584 * correction above so we do not accidentally free
4585 * all the metadata reservation because we might
4586 * actually need it later on.
4588 ext4_da_update_reserve_space(inode
, allocated_clusters
,
4594 * Cache the extent and update transaction to commit on fdatasync only
4595 * when it is _not_ an unwritten extent.
4597 if ((flags
& EXT4_GET_BLOCKS_UNWRIT_EXT
) == 0)
4598 ext4_update_inode_fsync_trans(handle
, inode
, 1);
4600 ext4_update_inode_fsync_trans(handle
, inode
, 0);
4602 if (allocated
> map
->m_len
)
4603 allocated
= map
->m_len
;
4604 ext4_ext_show_leaf(inode
, path
);
4605 map
->m_flags
|= EXT4_MAP_MAPPED
;
4606 map
->m_pblk
= newblock
;
4607 map
->m_len
= allocated
;
4609 ext4_ext_drop_refs(path
);
4612 trace_ext4_ext_map_blocks_exit(inode
, flags
, map
,
4613 err
? err
: allocated
);
4614 ext4_es_lru_add(inode
);
4615 return err
? err
: allocated
;
4618 void ext4_ext_truncate(handle_t
*handle
, struct inode
*inode
)
4620 struct super_block
*sb
= inode
->i_sb
;
4621 ext4_lblk_t last_block
;
4625 * TODO: optimization is possible here.
4626 * Probably we need not scan at all,
4627 * because page truncation is enough.
4630 /* we have to know where to truncate from in crash case */
4631 EXT4_I(inode
)->i_disksize
= inode
->i_size
;
4632 ext4_mark_inode_dirty(handle
, inode
);
4634 last_block
= (inode
->i_size
+ sb
->s_blocksize
- 1)
4635 >> EXT4_BLOCK_SIZE_BITS(sb
);
4637 err
= ext4_es_remove_extent(inode
, last_block
,
4638 EXT_MAX_BLOCKS
- last_block
);
4639 if (err
== -ENOMEM
) {
4641 congestion_wait(BLK_RW_ASYNC
, HZ
/50);
4645 ext4_std_error(inode
->i_sb
, err
);
4648 err
= ext4_ext_remove_space(inode
, last_block
, EXT_MAX_BLOCKS
- 1);
4649 ext4_std_error(inode
->i_sb
, err
);
4652 static int ext4_alloc_file_blocks(struct file
*file
, ext4_lblk_t offset
,
4653 ext4_lblk_t len
, loff_t new_size
,
4654 int flags
, int mode
)
4656 struct inode
*inode
= file_inode(file
);
4661 struct ext4_map_blocks map
;
4662 unsigned int credits
;
4665 map
.m_lblk
= offset
;
4668 * Don't normalize the request if it can fit in one extent so
4669 * that it doesn't get unnecessarily split into multiple
4672 if (len
<= EXT_UNWRITTEN_MAX_LEN
)
4673 flags
|= EXT4_GET_BLOCKS_NO_NORMALIZE
;
4676 * credits to insert 1 extent into extent tree
4678 credits
= ext4_chunk_trans_blocks(inode
, len
);
4681 while (ret
>= 0 && len
) {
4682 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
4684 if (IS_ERR(handle
)) {
4685 ret
= PTR_ERR(handle
);
4688 ret
= ext4_map_blocks(handle
, inode
, &map
, flags
);
4690 ext4_debug("inode #%lu: block %u: len %u: "
4691 "ext4_ext_map_blocks returned %d",
4692 inode
->i_ino
, map
.m_lblk
,
4694 ext4_mark_inode_dirty(handle
, inode
);
4695 ret2
= ext4_journal_stop(handle
);
4699 map
.m_len
= len
= len
- ret
;
4700 epos
= (loff_t
)map
.m_lblk
<< inode
->i_blkbits
;
4701 inode
->i_ctime
= ext4_current_time(inode
);
4703 if (epos
> new_size
)
4705 if (ext4_update_inode_size(inode
, epos
) & 0x1)
4706 inode
->i_mtime
= inode
->i_ctime
;
4708 if (epos
> inode
->i_size
)
4709 ext4_set_inode_flag(inode
,
4710 EXT4_INODE_EOFBLOCKS
);
4712 ext4_mark_inode_dirty(handle
, inode
);
4713 ret2
= ext4_journal_stop(handle
);
4717 if (ret
== -ENOSPC
&&
4718 ext4_should_retry_alloc(inode
->i_sb
, &retries
)) {
4723 return ret
> 0 ? ret2
: ret
;
4726 static long ext4_zero_range(struct file
*file
, loff_t offset
,
4727 loff_t len
, int mode
)
4729 struct inode
*inode
= file_inode(file
);
4730 handle_t
*handle
= NULL
;
4731 unsigned int max_blocks
;
4732 loff_t new_size
= 0;
4736 int partial_begin
, partial_end
;
4739 struct address_space
*mapping
= inode
->i_mapping
;
4740 unsigned int blkbits
= inode
->i_blkbits
;
4742 trace_ext4_zero_range(inode
, offset
, len
, mode
);
4744 if (!S_ISREG(inode
->i_mode
))
4747 /* Call ext4_force_commit to flush all data in case of data=journal. */
4748 if (ext4_should_journal_data(inode
)) {
4749 ret
= ext4_force_commit(inode
->i_sb
);
4755 * Write out all dirty pages to avoid race conditions
4756 * Then release them.
4758 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
4759 ret
= filemap_write_and_wait_range(mapping
, offset
,
4766 * Round up offset. This is not fallocate, we neet to zero out
4767 * blocks, so convert interior block aligned part of the range to
4768 * unwritten and possibly manually zero out unaligned parts of the
4771 start
= round_up(offset
, 1 << blkbits
);
4772 end
= round_down((offset
+ len
), 1 << blkbits
);
4774 if (start
< offset
|| end
> offset
+ len
)
4776 partial_begin
= offset
& ((1 << blkbits
) - 1);
4777 partial_end
= (offset
+ len
) & ((1 << blkbits
) - 1);
4779 lblk
= start
>> blkbits
;
4780 max_blocks
= (end
>> blkbits
);
4781 if (max_blocks
< lblk
)
4786 flags
= EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT
|
4787 EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
|
4789 if (mode
& FALLOC_FL_KEEP_SIZE
)
4790 flags
|= EXT4_GET_BLOCKS_KEEP_SIZE
;
4792 mutex_lock(&inode
->i_mutex
);
4795 * Indirect files do not support unwritten extnets
4797 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))) {
4802 if (!(mode
& FALLOC_FL_KEEP_SIZE
) &&
4803 offset
+ len
> i_size_read(inode
)) {
4804 new_size
= offset
+ len
;
4805 ret
= inode_newsize_ok(inode
, new_size
);
4809 * If we have a partial block after EOF we have to allocate
4816 if (max_blocks
> 0) {
4818 /* Now release the pages and zero block aligned part of pages*/
4819 truncate_pagecache_range(inode
, start
, end
- 1);
4820 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
4822 /* Wait all existing dio workers, newcomers will block on i_mutex */
4823 ext4_inode_block_unlocked_dio(inode
);
4824 inode_dio_wait(inode
);
4826 ret
= ext4_alloc_file_blocks(file
, lblk
, max_blocks
, new_size
,
4831 * Remove entire range from the extent status tree.
4833 * ext4_es_remove_extent(inode, lblk, max_blocks) is
4834 * NOT sufficient. I'm not sure why this is the case,
4835 * but let's be conservative and remove the extent
4836 * status tree for the entire inode. There should be
4837 * no outstanding delalloc extents thanks to the
4838 * filemap_write_and_wait_range() call above.
4840 ret
= ext4_es_remove_extent(inode
, 0, EXT_MAX_BLOCKS
);
4844 if (!partial_begin
&& !partial_end
)
4848 * In worst case we have to writeout two nonadjacent unwritten
4849 * blocks and update the inode
4851 credits
= (2 * ext4_ext_index_trans_blocks(inode
, 2)) + 1;
4852 if (ext4_should_journal_data(inode
))
4854 handle
= ext4_journal_start(inode
, EXT4_HT_MISC
, credits
);
4855 if (IS_ERR(handle
)) {
4856 ret
= PTR_ERR(handle
);
4857 ext4_std_error(inode
->i_sb
, ret
);
4861 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
4863 ext4_update_inode_size(inode
, new_size
);
4866 * Mark that we allocate beyond EOF so the subsequent truncate
4867 * can proceed even if the new size is the same as i_size.
4869 if ((offset
+ len
) > i_size_read(inode
))
4870 ext4_set_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
4872 ext4_mark_inode_dirty(handle
, inode
);
4874 /* Zero out partial block at the edges of the range */
4875 ret
= ext4_zero_partial_blocks(handle
, inode
, offset
, len
);
4877 if (file
->f_flags
& O_SYNC
)
4878 ext4_handle_sync(handle
);
4880 ext4_journal_stop(handle
);
4882 ext4_inode_resume_unlocked_dio(inode
);
4884 mutex_unlock(&inode
->i_mutex
);
4889 * preallocate space for a file. This implements ext4's fallocate file
4890 * operation, which gets called from sys_fallocate system call.
4891 * For block-mapped files, posix_fallocate should fall back to the method
4892 * of writing zeroes to the required new blocks (the same behavior which is
4893 * expected for file systems which do not support fallocate() system call).
4895 long ext4_fallocate(struct file
*file
, int mode
, loff_t offset
, loff_t len
)
4897 struct inode
*inode
= file_inode(file
);
4898 loff_t new_size
= 0;
4899 unsigned int max_blocks
;
4903 unsigned int blkbits
= inode
->i_blkbits
;
4905 /* Return error if mode is not supported */
4906 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
|
4907 FALLOC_FL_COLLAPSE_RANGE
| FALLOC_FL_ZERO_RANGE
))
4910 if (mode
& FALLOC_FL_PUNCH_HOLE
)
4911 return ext4_punch_hole(inode
, offset
, len
);
4913 ret
= ext4_convert_inline_data(inode
);
4918 * currently supporting (pre)allocate mode for extent-based
4921 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4924 if (mode
& FALLOC_FL_COLLAPSE_RANGE
)
4925 return ext4_collapse_range(inode
, offset
, len
);
4927 if (mode
& FALLOC_FL_ZERO_RANGE
)
4928 return ext4_zero_range(file
, offset
, len
, mode
);
4930 trace_ext4_fallocate_enter(inode
, offset
, len
, mode
);
4931 lblk
= offset
>> blkbits
;
4933 * We can't just convert len to max_blocks because
4934 * If blocksize = 4096 offset = 3072 and len = 2048
4936 max_blocks
= (EXT4_BLOCK_ALIGN(len
+ offset
, blkbits
) >> blkbits
)
4939 flags
= EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT
;
4940 if (mode
& FALLOC_FL_KEEP_SIZE
)
4941 flags
|= EXT4_GET_BLOCKS_KEEP_SIZE
;
4943 mutex_lock(&inode
->i_mutex
);
4945 if (!(mode
& FALLOC_FL_KEEP_SIZE
) &&
4946 offset
+ len
> i_size_read(inode
)) {
4947 new_size
= offset
+ len
;
4948 ret
= inode_newsize_ok(inode
, new_size
);
4953 ret
= ext4_alloc_file_blocks(file
, lblk
, max_blocks
, new_size
,
4958 if (file
->f_flags
& O_SYNC
&& EXT4_SB(inode
->i_sb
)->s_journal
) {
4959 ret
= jbd2_complete_transaction(EXT4_SB(inode
->i_sb
)->s_journal
,
4960 EXT4_I(inode
)->i_sync_tid
);
4963 mutex_unlock(&inode
->i_mutex
);
4964 trace_ext4_fallocate_exit(inode
, offset
, max_blocks
, ret
);
4969 * This function convert a range of blocks to written extents
4970 * The caller of this function will pass the start offset and the size.
4971 * all unwritten extents within this range will be converted to
4974 * This function is called from the direct IO end io call back
4975 * function, to convert the fallocated extents after IO is completed.
4976 * Returns 0 on success.
4978 int ext4_convert_unwritten_extents(handle_t
*handle
, struct inode
*inode
,
4979 loff_t offset
, ssize_t len
)
4981 unsigned int max_blocks
;
4984 struct ext4_map_blocks map
;
4985 unsigned int credits
, blkbits
= inode
->i_blkbits
;
4987 map
.m_lblk
= offset
>> blkbits
;
4989 * We can't just convert len to max_blocks because
4990 * If blocksize = 4096 offset = 3072 and len = 2048
4992 max_blocks
= ((EXT4_BLOCK_ALIGN(len
+ offset
, blkbits
) >> blkbits
) -
4995 * This is somewhat ugly but the idea is clear: When transaction is
4996 * reserved, everything goes into it. Otherwise we rather start several
4997 * smaller transactions for conversion of each extent separately.
5000 handle
= ext4_journal_start_reserved(handle
,
5001 EXT4_HT_EXT_CONVERT
);
5003 return PTR_ERR(handle
);
5007 * credits to insert 1 extent into extent tree
5009 credits
= ext4_chunk_trans_blocks(inode
, max_blocks
);
5011 while (ret
>= 0 && ret
< max_blocks
) {
5013 map
.m_len
= (max_blocks
-= ret
);
5015 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
5017 if (IS_ERR(handle
)) {
5018 ret
= PTR_ERR(handle
);
5022 ret
= ext4_map_blocks(handle
, inode
, &map
,
5023 EXT4_GET_BLOCKS_IO_CONVERT_EXT
);
5025 ext4_warning(inode
->i_sb
,
5026 "inode #%lu: block %u: len %u: "
5027 "ext4_ext_map_blocks returned %d",
5028 inode
->i_ino
, map
.m_lblk
,
5030 ext4_mark_inode_dirty(handle
, inode
);
5032 ret2
= ext4_journal_stop(handle
);
5033 if (ret
<= 0 || ret2
)
5037 ret2
= ext4_journal_stop(handle
);
5038 return ret
> 0 ? ret2
: ret
;
5042 * If newes is not existing extent (newes->ec_pblk equals zero) find
5043 * delayed extent at start of newes and update newes accordingly and
5044 * return start of the next delayed extent.
5046 * If newes is existing extent (newes->ec_pblk is not equal zero)
5047 * return start of next delayed extent or EXT_MAX_BLOCKS if no delayed
5048 * extent found. Leave newes unmodified.
5050 static int ext4_find_delayed_extent(struct inode
*inode
,
5051 struct extent_status
*newes
)
5053 struct extent_status es
;
5054 ext4_lblk_t block
, next_del
;
5056 if (newes
->es_pblk
== 0) {
5057 ext4_es_find_delayed_extent_range(inode
, newes
->es_lblk
,
5058 newes
->es_lblk
+ newes
->es_len
- 1, &es
);
5061 * No extent in extent-tree contains block @newes->es_pblk,
5062 * then the block may stay in 1)a hole or 2)delayed-extent.
5068 if (es
.es_lblk
> newes
->es_lblk
) {
5070 newes
->es_len
= min(es
.es_lblk
- newes
->es_lblk
,
5075 newes
->es_len
= es
.es_lblk
+ es
.es_len
- newes
->es_lblk
;
5078 block
= newes
->es_lblk
+ newes
->es_len
;
5079 ext4_es_find_delayed_extent_range(inode
, block
, EXT_MAX_BLOCKS
, &es
);
5081 next_del
= EXT_MAX_BLOCKS
;
5083 next_del
= es
.es_lblk
;
5087 /* fiemap flags we can handle specified here */
5088 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
5090 static int ext4_xattr_fiemap(struct inode
*inode
,
5091 struct fiemap_extent_info
*fieinfo
)
5095 __u32 flags
= FIEMAP_EXTENT_LAST
;
5096 int blockbits
= inode
->i_sb
->s_blocksize_bits
;
5100 if (ext4_test_inode_state(inode
, EXT4_STATE_XATTR
)) {
5101 struct ext4_iloc iloc
;
5102 int offset
; /* offset of xattr in inode */
5104 error
= ext4_get_inode_loc(inode
, &iloc
);
5107 physical
= (__u64
)iloc
.bh
->b_blocknr
<< blockbits
;
5108 offset
= EXT4_GOOD_OLD_INODE_SIZE
+
5109 EXT4_I(inode
)->i_extra_isize
;
5111 length
= EXT4_SB(inode
->i_sb
)->s_inode_size
- offset
;
5112 flags
|= FIEMAP_EXTENT_DATA_INLINE
;
5114 } else { /* external block */
5115 physical
= (__u64
)EXT4_I(inode
)->i_file_acl
<< blockbits
;
5116 length
= inode
->i_sb
->s_blocksize
;
5120 error
= fiemap_fill_next_extent(fieinfo
, 0, physical
,
5122 return (error
< 0 ? error
: 0);
5125 int ext4_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
5126 __u64 start
, __u64 len
)
5128 ext4_lblk_t start_blk
;
5131 if (ext4_has_inline_data(inode
)) {
5134 error
= ext4_inline_data_fiemap(inode
, fieinfo
, &has_inline
);
5140 if (fieinfo
->fi_flags
& FIEMAP_FLAG_CACHE
) {
5141 error
= ext4_ext_precache(inode
);
5146 /* fallback to generic here if not in extents fmt */
5147 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
5148 return generic_block_fiemap(inode
, fieinfo
, start
, len
,
5151 if (fiemap_check_flags(fieinfo
, EXT4_FIEMAP_FLAGS
))
5154 if (fieinfo
->fi_flags
& FIEMAP_FLAG_XATTR
) {
5155 error
= ext4_xattr_fiemap(inode
, fieinfo
);
5157 ext4_lblk_t len_blks
;
5160 start_blk
= start
>> inode
->i_sb
->s_blocksize_bits
;
5161 last_blk
= (start
+ len
- 1) >> inode
->i_sb
->s_blocksize_bits
;
5162 if (last_blk
>= EXT_MAX_BLOCKS
)
5163 last_blk
= EXT_MAX_BLOCKS
-1;
5164 len_blks
= ((ext4_lblk_t
) last_blk
) - start_blk
+ 1;
5167 * Walk the extent tree gathering extent information
5168 * and pushing extents back to the user.
5170 error
= ext4_fill_fiemap_extents(inode
, start_blk
,
5173 ext4_es_lru_add(inode
);
5179 * Function to access the path buffer for marking it dirty.
5180 * It also checks if there are sufficient credits left in the journal handle
5184 ext4_access_path(handle_t
*handle
, struct inode
*inode
,
5185 struct ext4_ext_path
*path
)
5189 if (!ext4_handle_valid(handle
))
5193 * Check if need to extend journal credits
5194 * 3 for leaf, sb, and inode plus 2 (bmap and group
5195 * descriptor) for each block group; assume two block
5198 if (handle
->h_buffer_credits
< 7) {
5199 credits
= ext4_writepage_trans_blocks(inode
);
5200 err
= ext4_ext_truncate_extend_restart(handle
, inode
, credits
);
5201 /* EAGAIN is success */
5202 if (err
&& err
!= -EAGAIN
)
5206 err
= ext4_ext_get_access(handle
, inode
, path
);
5211 * ext4_ext_shift_path_extents:
5212 * Shift the extents of a path structure lying between path[depth].p_ext
5213 * and EXT_LAST_EXTENT(path[depth].p_hdr) downwards, by subtracting shift
5214 * from starting block for each extent.
5217 ext4_ext_shift_path_extents(struct ext4_ext_path
*path
, ext4_lblk_t shift
,
5218 struct inode
*inode
, handle_t
*handle
,
5222 struct ext4_extent
*ex_start
, *ex_last
;
5224 depth
= path
->p_depth
;
5226 while (depth
>= 0) {
5227 if (depth
== path
->p_depth
) {
5228 ex_start
= path
[depth
].p_ext
;
5232 ex_last
= EXT_LAST_EXTENT(path
[depth
].p_hdr
);
5236 err
= ext4_access_path(handle
, inode
, path
+ depth
);
5240 if (ex_start
== EXT_FIRST_EXTENT(path
[depth
].p_hdr
))
5243 *start
= le32_to_cpu(ex_last
->ee_block
) +
5244 ext4_ext_get_actual_len(ex_last
);
5246 while (ex_start
<= ex_last
) {
5247 le32_add_cpu(&ex_start
->ee_block
, -shift
);
5248 /* Try to merge to the left. */
5250 EXT_FIRST_EXTENT(path
[depth
].p_hdr
)) &&
5251 ext4_ext_try_to_merge_right(inode
,
5252 path
, ex_start
- 1))
5257 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
5261 if (--depth
< 0 || !update
)
5265 /* Update index too */
5266 err
= ext4_access_path(handle
, inode
, path
+ depth
);
5270 le32_add_cpu(&path
[depth
].p_idx
->ei_block
, -shift
);
5271 err
= ext4_ext_dirty(handle
, inode
, path
+ depth
);
5275 /* we are done if current index is not a starting index */
5276 if (path
[depth
].p_idx
!= EXT_FIRST_INDEX(path
[depth
].p_hdr
))
5287 * ext4_ext_shift_extents:
5288 * All the extents which lies in the range from start to the last allocated
5289 * block for the file are shifted downwards by shift blocks.
5290 * On success, 0 is returned, error otherwise.
5293 ext4_ext_shift_extents(struct inode
*inode
, handle_t
*handle
,
5294 ext4_lblk_t start
, ext4_lblk_t shift
)
5296 struct ext4_ext_path
*path
;
5298 struct ext4_extent
*extent
;
5299 ext4_lblk_t stop_block
;
5300 ext4_lblk_t ex_start
, ex_end
;
5302 /* Let path point to the last extent */
5303 path
= ext4_ext_find_extent(inode
, EXT_MAX_BLOCKS
- 1, NULL
, 0);
5305 return PTR_ERR(path
);
5307 depth
= path
->p_depth
;
5308 extent
= path
[depth
].p_ext
;
5310 ext4_ext_drop_refs(path
);
5315 stop_block
= le32_to_cpu(extent
->ee_block
) +
5316 ext4_ext_get_actual_len(extent
);
5317 ext4_ext_drop_refs(path
);
5320 /* Nothing to shift, if hole is at the end of file */
5321 if (start
>= stop_block
)
5325 * Don't start shifting extents until we make sure the hole is big
5326 * enough to accomodate the shift.
5328 path
= ext4_ext_find_extent(inode
, start
- 1, NULL
, 0);
5330 return PTR_ERR(path
);
5331 depth
= path
->p_depth
;
5332 extent
= path
[depth
].p_ext
;
5334 ex_start
= le32_to_cpu(extent
->ee_block
);
5335 ex_end
= le32_to_cpu(extent
->ee_block
) +
5336 ext4_ext_get_actual_len(extent
);
5341 ext4_ext_drop_refs(path
);
5344 if ((start
== ex_start
&& shift
> ex_start
) ||
5345 (shift
> start
- ex_end
))
5348 /* Its safe to start updating extents */
5349 while (start
< stop_block
) {
5350 path
= ext4_ext_find_extent(inode
, start
, NULL
, 0);
5352 return PTR_ERR(path
);
5353 depth
= path
->p_depth
;
5354 extent
= path
[depth
].p_ext
;
5356 EXT4_ERROR_INODE(inode
, "unexpected hole at %lu",
5357 (unsigned long) start
);
5360 if (start
> le32_to_cpu(extent
->ee_block
)) {
5361 /* Hole, move to the next extent */
5362 if (extent
< EXT_LAST_EXTENT(path
[depth
].p_hdr
)) {
5363 path
[depth
].p_ext
++;
5365 start
= ext4_ext_next_allocated_block(path
);
5366 ext4_ext_drop_refs(path
);
5371 ret
= ext4_ext_shift_path_extents(path
, shift
, inode
,
5373 ext4_ext_drop_refs(path
);
5383 * ext4_collapse_range:
5384 * This implements the fallocate's collapse range functionality for ext4
5385 * Returns: 0 and non-zero on error.
5387 int ext4_collapse_range(struct inode
*inode
, loff_t offset
, loff_t len
)
5389 struct super_block
*sb
= inode
->i_sb
;
5390 ext4_lblk_t punch_start
, punch_stop
;
5392 unsigned int credits
;
5393 loff_t new_size
, ioffset
;
5396 /* Collapse range works only on fs block size aligned offsets. */
5397 if (offset
& (EXT4_CLUSTER_SIZE(sb
) - 1) ||
5398 len
& (EXT4_CLUSTER_SIZE(sb
) - 1))
5401 if (!S_ISREG(inode
->i_mode
))
5404 trace_ext4_collapse_range(inode
, offset
, len
);
5406 punch_start
= offset
>> EXT4_BLOCK_SIZE_BITS(sb
);
5407 punch_stop
= (offset
+ len
) >> EXT4_BLOCK_SIZE_BITS(sb
);
5409 /* Call ext4_force_commit to flush all data in case of data=journal. */
5410 if (ext4_should_journal_data(inode
)) {
5411 ret
= ext4_force_commit(inode
->i_sb
);
5417 * Need to round down offset to be aligned with page size boundary
5418 * for page size > block size.
5420 ioffset
= round_down(offset
, PAGE_SIZE
);
5422 /* Write out all dirty pages */
5423 ret
= filemap_write_and_wait_range(inode
->i_mapping
, ioffset
,
5428 /* Take mutex lock */
5429 mutex_lock(&inode
->i_mutex
);
5432 * There is no need to overlap collapse range with EOF, in which case
5433 * it is effectively a truncate operation
5435 if (offset
+ len
>= i_size_read(inode
)) {
5440 /* Currently just for extent based files */
5441 if (!ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
5446 truncate_pagecache(inode
, ioffset
);
5448 /* Wait for existing dio to complete */
5449 ext4_inode_block_unlocked_dio(inode
);
5450 inode_dio_wait(inode
);
5452 credits
= ext4_writepage_trans_blocks(inode
);
5453 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
5454 if (IS_ERR(handle
)) {
5455 ret
= PTR_ERR(handle
);
5459 down_write(&EXT4_I(inode
)->i_data_sem
);
5460 ext4_discard_preallocations(inode
);
5462 ret
= ext4_es_remove_extent(inode
, punch_start
,
5463 EXT_MAX_BLOCKS
- punch_start
);
5465 up_write(&EXT4_I(inode
)->i_data_sem
);
5469 ret
= ext4_ext_remove_space(inode
, punch_start
, punch_stop
- 1);
5471 up_write(&EXT4_I(inode
)->i_data_sem
);
5474 ext4_discard_preallocations(inode
);
5476 ret
= ext4_ext_shift_extents(inode
, handle
, punch_stop
,
5477 punch_stop
- punch_start
);
5479 up_write(&EXT4_I(inode
)->i_data_sem
);
5483 new_size
= i_size_read(inode
) - len
;
5484 i_size_write(inode
, new_size
);
5485 EXT4_I(inode
)->i_disksize
= new_size
;
5487 up_write(&EXT4_I(inode
)->i_data_sem
);
5489 ext4_handle_sync(handle
);
5490 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
5491 ext4_mark_inode_dirty(handle
, inode
);
5494 ext4_journal_stop(handle
);
5496 ext4_inode_resume_unlocked_dio(inode
);
5498 mutex_unlock(&inode
->i_mutex
);
5503 * ext4_swap_extents - Swap extents between two inodes
5505 * @inode1: First inode
5506 * @inode2: Second inode
5507 * @lblk1: Start block for first inode
5508 * @lblk2: Start block for second inode
5509 * @count: Number of blocks to swap
5510 * @mark_unwritten: Mark second inode's extents as unwritten after swap
5511 * @erp: Pointer to save error value
5513 * This helper routine does exactly what is promise "swap extents". All other
5514 * stuff such as page-cache locking consistency, bh mapping consistency or
5515 * extent's data copying must be performed by caller.
5517 * i_mutex is held for both inodes
5518 * i_data_sem is locked for write for both inodes
5520 * All pages from requested range are locked for both inodes
5523 ext4_swap_extents(handle_t
*handle
, struct inode
*inode1
,
5524 struct inode
*inode2
, ext4_lblk_t lblk1
, ext4_lblk_t lblk2
,
5525 ext4_lblk_t count
, int unwritten
, int *erp
)
5527 struct ext4_ext_path
*path1
= NULL
;
5528 struct ext4_ext_path
*path2
= NULL
;
5529 int replaced_count
= 0;
5531 BUG_ON(!rwsem_is_locked(&EXT4_I(inode1
)->i_data_sem
));
5532 BUG_ON(!rwsem_is_locked(&EXT4_I(inode2
)->i_data_sem
));
5533 BUG_ON(!mutex_is_locked(&inode1
->i_mutex
));
5534 BUG_ON(!mutex_is_locked(&inode1
->i_mutex
));
5536 *erp
= ext4_es_remove_extent(inode1
, lblk1
, count
);
5539 *erp
= ext4_es_remove_extent(inode2
, lblk2
, count
);
5544 struct ext4_extent
*ex1
, *ex2
, tmp_ex
;
5545 ext4_lblk_t e1_blk
, e2_blk
;
5546 int e1_len
, e2_len
, len
;
5549 path1
= ext4_ext_find_extent(inode1
, lblk1
, NULL
, EXT4_EX_NOCACHE
);
5550 if (unlikely(IS_ERR(path1
))) {
5551 *erp
= PTR_ERR(path1
);
5557 path2
= ext4_ext_find_extent(inode2
, lblk2
, NULL
, EXT4_EX_NOCACHE
);
5558 if (unlikely(IS_ERR(path2
))) {
5559 *erp
= PTR_ERR(path2
);
5563 ex1
= path1
[path1
->p_depth
].p_ext
;
5564 ex2
= path2
[path2
->p_depth
].p_ext
;
5565 /* Do we have somthing to swap ? */
5566 if (unlikely(!ex2
|| !ex1
))
5569 e1_blk
= le32_to_cpu(ex1
->ee_block
);
5570 e2_blk
= le32_to_cpu(ex2
->ee_block
);
5571 e1_len
= ext4_ext_get_actual_len(ex1
);
5572 e2_len
= ext4_ext_get_actual_len(ex2
);
5575 if (!in_range(lblk1
, e1_blk
, e1_len
) ||
5576 !in_range(lblk2
, e2_blk
, e2_len
)) {
5577 ext4_lblk_t next1
, next2
;
5579 /* if hole after extent, then go to next extent */
5580 next1
= ext4_ext_next_allocated_block(path1
);
5581 next2
= ext4_ext_next_allocated_block(path2
);
5582 /* If hole before extent, then shift to that extent */
5587 /* Do we have something to swap */
5588 if (next1
== EXT_MAX_BLOCKS
|| next2
== EXT_MAX_BLOCKS
)
5590 /* Move to the rightest boundary */
5591 len
= next1
- lblk1
;
5592 if (len
< next2
- lblk2
)
5593 len
= next2
- lblk2
;
5602 /* Prepare left boundary */
5603 if (e1_blk
< lblk1
) {
5605 *erp
= ext4_force_split_extent_at(handle
, inode1
,
5610 if (e2_blk
< lblk2
) {
5612 *erp
= ext4_force_split_extent_at(handle
, inode2
,
5617 /* ext4_split_extent_at() may result in leaf extent split,
5618 * path must to be revalidated. */
5622 /* Prepare right boundary */
5624 if (len
> e1_blk
+ e1_len
- lblk1
)
5625 len
= e1_blk
+ e1_len
- lblk1
;
5626 if (len
> e2_blk
+ e2_len
- lblk2
)
5627 len
= e2_blk
+ e2_len
- lblk2
;
5629 if (len
!= e1_len
) {
5631 *erp
= ext4_force_split_extent_at(handle
, inode1
,
5632 &path1
, lblk1
+ len
, 0);
5636 if (len
!= e2_len
) {
5638 *erp
= ext4_force_split_extent_at(handle
, inode2
,
5639 &path2
, lblk2
+ len
, 0);
5643 /* ext4_split_extent_at() may result in leaf extent split,
5644 * path must to be revalidated. */
5648 BUG_ON(e2_len
!= e1_len
);
5649 *erp
= ext4_ext_get_access(handle
, inode1
, path1
+ path1
->p_depth
);
5652 *erp
= ext4_ext_get_access(handle
, inode2
, path2
+ path2
->p_depth
);
5656 /* Both extents are fully inside boundaries. Swap it now */
5658 ext4_ext_store_pblock(ex1
, ext4_ext_pblock(ex2
));
5659 ext4_ext_store_pblock(ex2
, ext4_ext_pblock(&tmp_ex
));
5660 ex1
->ee_len
= cpu_to_le16(e2_len
);
5661 ex2
->ee_len
= cpu_to_le16(e1_len
);
5663 ext4_ext_mark_unwritten(ex2
);
5664 if (ext4_ext_is_unwritten(&tmp_ex
))
5665 ext4_ext_mark_unwritten(ex1
);
5667 ext4_ext_try_to_merge(handle
, inode2
, path2
, ex2
);
5668 ext4_ext_try_to_merge(handle
, inode1
, path1
, ex1
);
5669 *erp
= ext4_ext_dirty(handle
, inode2
, path2
+
5673 *erp
= ext4_ext_dirty(handle
, inode1
, path1
+
5676 * Looks scarry ah..? second inode already points to new blocks,
5677 * and it was successfully dirtied. But luckily error may happen
5678 * only due to journal error, so full transaction will be
5685 replaced_count
+= len
;
5689 ext4_ext_drop_refs(path1
);
5691 ext4_ext_drop_refs(path2
);
5693 path1
= path2
= NULL
;
5695 return replaced_count
;