2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * Copyright (c) 2016 Christoph Hellwig.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it would be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 #include <linux/iomap.h>
22 #include "xfs_shared.h"
23 #include "xfs_format.h"
24 #include "xfs_log_format.h"
25 #include "xfs_trans_resv.h"
26 #include "xfs_mount.h"
27 #include "xfs_defer.h"
28 #include "xfs_inode.h"
29 #include "xfs_btree.h"
30 #include "xfs_bmap_btree.h"
32 #include "xfs_bmap_util.h"
33 #include "xfs_error.h"
34 #include "xfs_trans.h"
35 #include "xfs_trans_space.h"
36 #include "xfs_iomap.h"
37 #include "xfs_trace.h"
38 #include "xfs_icache.h"
39 #include "xfs_quota.h"
40 #include "xfs_dquot_item.h"
41 #include "xfs_dquot.h"
44 #define XFS_WRITEIO_ALIGN(mp,off) (((off) >> mp->m_writeio_log) \
51 struct xfs_bmbt_irec
*imap
)
53 struct xfs_mount
*mp
= ip
->i_mount
;
55 if (imap
->br_startblock
== HOLESTARTBLOCK
) {
56 iomap
->blkno
= IOMAP_NULL_BLOCK
;
57 iomap
->type
= IOMAP_HOLE
;
58 } else if (imap
->br_startblock
== DELAYSTARTBLOCK
) {
59 iomap
->blkno
= IOMAP_NULL_BLOCK
;
60 iomap
->type
= IOMAP_DELALLOC
;
62 iomap
->blkno
= xfs_fsb_to_db(ip
, imap
->br_startblock
);
63 if (imap
->br_state
== XFS_EXT_UNWRITTEN
)
64 iomap
->type
= IOMAP_UNWRITTEN
;
66 iomap
->type
= IOMAP_MAPPED
;
68 iomap
->offset
= XFS_FSB_TO_B(mp
, imap
->br_startoff
);
69 iomap
->length
= XFS_FSB_TO_B(mp
, imap
->br_blockcount
);
70 iomap
->bdev
= xfs_find_bdev_for_inode(VFS_I(ip
));
78 struct xfs_mount
*mp
= ip
->i_mount
;
79 xfs_extlen_t align
= 0;
81 if (!XFS_IS_REALTIME_INODE(ip
)) {
83 * Round up the allocation request to a stripe unit
84 * (m_dalign) boundary if the file size is >= stripe unit
85 * size, and we are allocating past the allocation eof.
87 * If mounted with the "-o swalloc" option the alignment is
88 * increased from the strip unit size to the stripe width.
90 if (mp
->m_swidth
&& (mp
->m_flags
& XFS_MOUNT_SWALLOC
))
92 else if (mp
->m_dalign
)
95 if (align
&& XFS_ISIZE(ip
) < XFS_FSB_TO_B(mp
, align
))
100 * Always round up the allocation request to an extent boundary
101 * (when file on a real-time subvolume or has di_extsize hint).
105 align
= roundup_64(align
, extsize
);
114 xfs_iomap_eof_align_last_fsb(
115 struct xfs_inode
*ip
,
116 xfs_extlen_t extsize
,
117 xfs_fileoff_t
*last_fsb
)
119 xfs_extlen_t align
= xfs_eof_alignment(ip
, extsize
);
122 xfs_fileoff_t new_last_fsb
= roundup_64(*last_fsb
, align
);
125 error
= xfs_bmap_eof(ip
, new_last_fsb
, XFS_DATA_FORK
, &eof
);
129 *last_fsb
= new_last_fsb
;
135 xfs_alert_fsblock_zero(
137 xfs_bmbt_irec_t
*imap
)
139 xfs_alert_tag(ip
->i_mount
, XFS_PTAG_FSBLOCK_ZERO
,
140 "Access to block zero in inode %llu "
141 "start_block: %llx start_off: %llx "
142 "blkcnt: %llx extent-state: %x",
143 (unsigned long long)ip
->i_ino
,
144 (unsigned long long)imap
->br_startblock
,
145 (unsigned long long)imap
->br_startoff
,
146 (unsigned long long)imap
->br_blockcount
,
148 return -EFSCORRUPTED
;
152 xfs_iomap_write_direct(
156 xfs_bmbt_irec_t
*imap
,
159 xfs_mount_t
*mp
= ip
->i_mount
;
160 xfs_fileoff_t offset_fsb
;
161 xfs_fileoff_t last_fsb
;
162 xfs_filblks_t count_fsb
, resaligned
;
163 xfs_fsblock_t firstfsb
;
164 xfs_extlen_t extsz
, temp
;
169 struct xfs_defer_ops dfops
;
170 uint qblocks
, resblks
, resrtextents
;
173 int bmapi_flags
= XFS_BMAPI_PREALLOC
;
176 rt
= XFS_IS_REALTIME_INODE(ip
);
177 extsz
= xfs_get_extsz_hint(ip
);
178 lockmode
= XFS_ILOCK_SHARED
; /* locked by caller */
180 ASSERT(xfs_isilocked(ip
, lockmode
));
182 offset_fsb
= XFS_B_TO_FSBT(mp
, offset
);
183 last_fsb
= XFS_B_TO_FSB(mp
, ((xfs_ufsize_t
)(offset
+ count
)));
184 if ((offset
+ count
) > XFS_ISIZE(ip
)) {
186 * Assert that the in-core extent list is present since this can
187 * call xfs_iread_extents() and we only have the ilock shared.
188 * This should be safe because the lock was held around a bmapi
189 * call in the caller and we only need it to access the in-core
192 ASSERT(XFS_IFORK_PTR(ip
, XFS_DATA_FORK
)->if_flags
&
194 error
= xfs_iomap_eof_align_last_fsb(ip
, extsz
, &last_fsb
);
198 if (nmaps
&& (imap
->br_startblock
== HOLESTARTBLOCK
))
199 last_fsb
= MIN(last_fsb
, (xfs_fileoff_t
)
200 imap
->br_blockcount
+
203 count_fsb
= last_fsb
- offset_fsb
;
204 ASSERT(count_fsb
> 0);
206 resaligned
= count_fsb
;
207 if (unlikely(extsz
)) {
208 if ((temp
= do_mod(offset_fsb
, extsz
)))
210 if ((temp
= do_mod(resaligned
, extsz
)))
211 resaligned
+= extsz
- temp
;
215 resrtextents
= qblocks
= resaligned
;
216 resrtextents
/= mp
->m_sb
.sb_rextsize
;
217 resblks
= XFS_DIOSTRAT_SPACE_RES(mp
, 0);
218 quota_flag
= XFS_QMOPT_RES_RTBLKS
;
221 resblks
= qblocks
= XFS_DIOSTRAT_SPACE_RES(mp
, resaligned
);
222 quota_flag
= XFS_QMOPT_RES_REGBLKS
;
226 * Drop the shared lock acquired by the caller, attach the dquot if
227 * necessary and move on to transaction setup.
229 xfs_iunlock(ip
, lockmode
);
230 error
= xfs_qm_dqattach(ip
, 0);
235 * For DAX, we do not allocate unwritten extents, but instead we zero
236 * the block before we commit the transaction. Ideally we'd like to do
237 * this outside the transaction context, but if we commit and then crash
238 * we may not have zeroed the blocks and this will be exposed on
239 * recovery of the allocation. Hence we must zero before commit.
241 * Further, if we are mapping unwritten extents here, we need to zero
242 * and convert them to written so that we don't need an unwritten extent
243 * callback for DAX. This also means that we need to be able to dip into
244 * the reserve block pool for bmbt block allocation if there is no space
245 * left but we need to do unwritten extent conversion.
247 if (IS_DAX(VFS_I(ip
))) {
248 bmapi_flags
= XFS_BMAPI_CONVERT
| XFS_BMAPI_ZERO
;
249 if (ISUNWRITTEN(imap
)) {
250 tflags
|= XFS_TRANS_RESERVE
;
251 resblks
= XFS_DIOSTRAT_SPACE_RES(mp
, 0) << 1;
254 error
= xfs_trans_alloc(mp
, &M_RES(mp
)->tr_write
, resblks
, resrtextents
,
259 lockmode
= XFS_ILOCK_EXCL
;
260 xfs_ilock(ip
, lockmode
);
262 error
= xfs_trans_reserve_quota_nblks(tp
, ip
, qblocks
, 0, quota_flag
);
264 goto out_trans_cancel
;
266 xfs_trans_ijoin(tp
, ip
, 0);
269 * From this point onwards we overwrite the imap pointer that the
272 xfs_defer_init(&dfops
, &firstfsb
);
274 error
= xfs_bmapi_write(tp
, ip
, offset_fsb
, count_fsb
,
275 bmapi_flags
, &firstfsb
, resblks
, imap
,
278 goto out_bmap_cancel
;
281 * Complete the transaction
283 error
= xfs_defer_finish(&tp
, &dfops
, NULL
);
285 goto out_bmap_cancel
;
287 error
= xfs_trans_commit(tp
);
292 * Copy any maps to caller's array and return any error.
299 if (!(imap
->br_startblock
|| XFS_IS_REALTIME_INODE(ip
)))
300 error
= xfs_alert_fsblock_zero(ip
, imap
);
303 xfs_iunlock(ip
, lockmode
);
307 xfs_defer_cancel(&dfops
);
308 xfs_trans_unreserve_quota_nblks(tp
, ip
, (long)qblocks
, 0, quota_flag
);
310 xfs_trans_cancel(tp
);
315 xfs_quota_need_throttle(
316 struct xfs_inode
*ip
,
318 xfs_fsblock_t alloc_blocks
)
320 struct xfs_dquot
*dq
= xfs_inode_dquot(ip
, type
);
322 if (!dq
|| !xfs_this_quota_on(ip
->i_mount
, type
))
325 /* no hi watermark, no throttle */
326 if (!dq
->q_prealloc_hi_wmark
)
329 /* under the lo watermark, no throttle */
330 if (dq
->q_res_bcount
+ alloc_blocks
< dq
->q_prealloc_lo_wmark
)
337 xfs_quota_calc_throttle(
338 struct xfs_inode
*ip
,
340 xfs_fsblock_t
*qblocks
,
346 struct xfs_dquot
*dq
= xfs_inode_dquot(ip
, type
);
348 /* no dq, or over hi wmark, squash the prealloc completely */
349 if (!dq
|| dq
->q_res_bcount
>= dq
->q_prealloc_hi_wmark
) {
355 freesp
= dq
->q_prealloc_hi_wmark
- dq
->q_res_bcount
;
356 if (freesp
< dq
->q_low_space
[XFS_QLOWSP_5_PCNT
]) {
358 if (freesp
< dq
->q_low_space
[XFS_QLOWSP_3_PCNT
])
360 if (freesp
< dq
->q_low_space
[XFS_QLOWSP_1_PCNT
])
364 if (freesp
< *qfreesp
)
367 /* only overwrite the throttle values if we are more aggressive */
368 if ((freesp
>> shift
) < (*qblocks
>> *qshift
)) {
375 * If we are doing a write at the end of the file and there are no allocations
376 * past this one, then extend the allocation out to the file system's write
379 * If we don't have a user specified preallocation size, dynamically increase
380 * the preallocation size as the size of the file grows. Cap the maximum size
381 * at a single extent or less if the filesystem is near full. The closer the
382 * filesystem is to full, the smaller the maximum prealocation.
384 * As an exception we don't do any preallocation at all if the file is smaller
385 * than the minimum preallocation and we are using the default dynamic
386 * preallocation scheme, as it is likely this is the only write to the file that
387 * is going to be done.
389 * We clean up any extra space left over when the file is closed in
393 xfs_iomap_prealloc_size(
394 struct xfs_inode
*ip
,
398 struct xfs_bmbt_irec
*prev
)
400 struct xfs_mount
*mp
= ip
->i_mount
;
401 xfs_fileoff_t offset_fsb
= XFS_B_TO_FSBT(mp
, offset
);
404 xfs_fsblock_t qblocks
;
406 xfs_fsblock_t alloc_blocks
= 0;
408 if (offset
+ count
<= XFS_ISIZE(ip
))
411 if (!(mp
->m_flags
& XFS_MOUNT_DFLT_IOSIZE
) &&
412 (XFS_ISIZE(ip
) < XFS_FSB_TO_B(mp
, mp
->m_writeio_blocks
)))
416 * If an explicit allocsize is set, the file is small, or we
417 * are writing behind a hole, then use the minimum prealloc:
419 if ((mp
->m_flags
& XFS_MOUNT_DFLT_IOSIZE
) ||
420 XFS_ISIZE(ip
) < XFS_FSB_TO_B(mp
, mp
->m_dalign
) ||
422 prev
->br_startoff
+ prev
->br_blockcount
< offset_fsb
)
423 return mp
->m_writeio_blocks
;
426 * Determine the initial size of the preallocation. We are beyond the
427 * current EOF here, but we need to take into account whether this is
428 * a sparse write or an extending write when determining the
429 * preallocation size. Hence we need to look up the extent that ends
430 * at the current write offset and use the result to determine the
431 * preallocation size.
433 * If the extent is a hole, then preallocation is essentially disabled.
434 * Otherwise we take the size of the preceding data extent as the basis
435 * for the preallocation size. If the size of the extent is greater than
436 * half the maximum extent length, then use the current offset as the
437 * basis. This ensures that for large files the preallocation size
438 * always extends to MAXEXTLEN rather than falling short due to things
439 * like stripe unit/width alignment of real extents.
441 if (prev
->br_blockcount
<= (MAXEXTLEN
>> 1))
442 alloc_blocks
= prev
->br_blockcount
<< 1;
444 alloc_blocks
= XFS_B_TO_FSB(mp
, offset
);
447 qblocks
= alloc_blocks
;
450 * MAXEXTLEN is not a power of two value but we round the prealloc down
451 * to the nearest power of two value after throttling. To prevent the
452 * round down from unconditionally reducing the maximum supported prealloc
453 * size, we round up first, apply appropriate throttling, round down and
454 * cap the value to MAXEXTLEN.
456 alloc_blocks
= XFS_FILEOFF_MIN(roundup_pow_of_two(MAXEXTLEN
),
459 freesp
= percpu_counter_read_positive(&mp
->m_fdblocks
);
460 if (freesp
< mp
->m_low_space
[XFS_LOWSP_5_PCNT
]) {
462 if (freesp
< mp
->m_low_space
[XFS_LOWSP_4_PCNT
])
464 if (freesp
< mp
->m_low_space
[XFS_LOWSP_3_PCNT
])
466 if (freesp
< mp
->m_low_space
[XFS_LOWSP_2_PCNT
])
468 if (freesp
< mp
->m_low_space
[XFS_LOWSP_1_PCNT
])
473 * Check each quota to cap the prealloc size, provide a shift value to
474 * throttle with and adjust amount of available space.
476 if (xfs_quota_need_throttle(ip
, XFS_DQ_USER
, alloc_blocks
))
477 xfs_quota_calc_throttle(ip
, XFS_DQ_USER
, &qblocks
, &qshift
,
479 if (xfs_quota_need_throttle(ip
, XFS_DQ_GROUP
, alloc_blocks
))
480 xfs_quota_calc_throttle(ip
, XFS_DQ_GROUP
, &qblocks
, &qshift
,
482 if (xfs_quota_need_throttle(ip
, XFS_DQ_PROJ
, alloc_blocks
))
483 xfs_quota_calc_throttle(ip
, XFS_DQ_PROJ
, &qblocks
, &qshift
,
487 * The final prealloc size is set to the minimum of free space available
488 * in each of the quotas and the overall filesystem.
490 * The shift throttle value is set to the maximum value as determined by
491 * the global low free space values and per-quota low free space values.
493 alloc_blocks
= MIN(alloc_blocks
, qblocks
);
494 shift
= MAX(shift
, qshift
);
497 alloc_blocks
>>= shift
;
499 * rounddown_pow_of_two() returns an undefined result if we pass in
503 alloc_blocks
= rounddown_pow_of_two(alloc_blocks
);
504 if (alloc_blocks
> MAXEXTLEN
)
505 alloc_blocks
= MAXEXTLEN
;
508 * If we are still trying to allocate more space than is
509 * available, squash the prealloc hard. This can happen if we
510 * have a large file on a small filesystem and the above
511 * lowspace thresholds are smaller than MAXEXTLEN.
513 while (alloc_blocks
&& alloc_blocks
>= freesp
)
516 if (alloc_blocks
< mp
->m_writeio_blocks
)
517 alloc_blocks
= mp
->m_writeio_blocks
;
518 trace_xfs_iomap_prealloc_size(ip
, alloc_blocks
, shift
,
519 mp
->m_writeio_blocks
);
524 xfs_file_iomap_begin_delay(
531 struct xfs_inode
*ip
= XFS_I(inode
);
532 struct xfs_mount
*mp
= ip
->i_mount
;
533 struct xfs_ifork
*ifp
= XFS_IFORK_PTR(ip
, XFS_DATA_FORK
);
534 xfs_fileoff_t offset_fsb
= XFS_B_TO_FSBT(mp
, offset
);
535 xfs_fileoff_t maxbytes_fsb
=
536 XFS_B_TO_FSB(mp
, mp
->m_super
->s_maxbytes
);
537 xfs_fileoff_t end_fsb
, orig_end_fsb
;
538 int error
= 0, eof
= 0;
539 struct xfs_bmbt_irec got
;
540 struct xfs_bmbt_irec prev
;
543 ASSERT(!XFS_IS_REALTIME_INODE(ip
));
544 ASSERT(!xfs_get_extsz_hint(ip
));
546 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
548 if (unlikely(XFS_TEST_ERROR(
549 (XFS_IFORK_FORMAT(ip
, XFS_DATA_FORK
) != XFS_DINODE_FMT_EXTENTS
&&
550 XFS_IFORK_FORMAT(ip
, XFS_DATA_FORK
) != XFS_DINODE_FMT_BTREE
),
551 mp
, XFS_ERRTAG_BMAPIFORMAT
, XFS_RANDOM_BMAPIFORMAT
))) {
552 XFS_ERROR_REPORT(__func__
, XFS_ERRLEVEL_LOW
, mp
);
553 error
= -EFSCORRUPTED
;
557 XFS_STATS_INC(mp
, xs_blk_mapw
);
559 if (!(ifp
->if_flags
& XFS_IFEXTENTS
)) {
560 error
= xfs_iread_extents(NULL
, ip
, XFS_DATA_FORK
);
565 xfs_bmap_search_extents(ip
, offset_fsb
, XFS_DATA_FORK
, &eof
, &idx
,
567 if (!eof
&& got
.br_startoff
<= offset_fsb
) {
568 trace_xfs_iomap_found(ip
, offset
, count
, 0, &got
);
572 error
= xfs_qm_dqattach_locked(ip
, 0);
577 * We cap the maximum length we map here to MAX_WRITEBACK_PAGES pages
578 * to keep the chunks of work done where somewhat symmetric with the
579 * work writeback does. This is a completely arbitrary number pulled
580 * out of thin air as a best guess for initial testing.
582 * Note that the values needs to be less than 32-bits wide until
583 * the lower level functions are updated.
585 count
= min_t(loff_t
, count
, 1024 * PAGE_SIZE
);
586 end_fsb
= orig_end_fsb
=
587 min(XFS_B_TO_FSB(mp
, offset
+ count
), maxbytes_fsb
);
590 xfs_fsblock_t prealloc_blocks
;
593 xfs_iomap_prealloc_size(ip
, offset
, count
, idx
, &prev
);
594 if (prealloc_blocks
) {
596 xfs_off_t end_offset
;
598 end_offset
= XFS_WRITEIO_ALIGN(mp
, offset
+ count
- 1);
599 end_fsb
= XFS_B_TO_FSBT(mp
, end_offset
) +
602 align
= xfs_eof_alignment(ip
, 0);
604 end_fsb
= roundup_64(end_fsb
, align
);
606 end_fsb
= min(end_fsb
, maxbytes_fsb
);
607 ASSERT(end_fsb
> offset_fsb
);
612 error
= xfs_bmapi_reserve_delalloc(ip
, offset_fsb
,
613 end_fsb
- offset_fsb
, &got
,
620 /* retry without any preallocation */
621 trace_xfs_delalloc_enospc(ip
, offset
, count
);
622 if (end_fsb
!= orig_end_fsb
) {
623 end_fsb
= orig_end_fsb
;
632 * Tag the inode as speculatively preallocated so we can reclaim this
633 * space on demand, if necessary.
635 if (end_fsb
!= orig_end_fsb
)
636 xfs_inode_set_eofblocks_tag(ip
);
638 trace_xfs_iomap_alloc(ip
, offset
, count
, 0, &got
);
640 if (isnullstartblock(got
.br_startblock
))
641 got
.br_startblock
= DELAYSTARTBLOCK
;
643 if (!got
.br_startblock
) {
644 error
= xfs_alert_fsblock_zero(ip
, &got
);
649 xfs_bmbt_to_iomap(ip
, iomap
, &got
);
652 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
657 * Pass in a delayed allocate extent, convert it to real extents;
658 * return to the caller the extent we create which maps on top of
659 * the originating callers request.
661 * Called without a lock on the inode.
663 * We no longer bother to look at the incoming map - all we have to
664 * guarantee is that whatever we allocate fills the required range.
667 xfs_iomap_write_allocate(
670 xfs_bmbt_irec_t
*imap
)
672 xfs_mount_t
*mp
= ip
->i_mount
;
673 xfs_fileoff_t offset_fsb
, last_block
;
674 xfs_fileoff_t end_fsb
, map_start_fsb
;
675 xfs_fsblock_t first_block
;
676 struct xfs_defer_ops dfops
;
677 xfs_filblks_t count_fsb
;
684 * Make sure that the dquots are there.
686 error
= xfs_qm_dqattach(ip
, 0);
690 offset_fsb
= XFS_B_TO_FSBT(mp
, offset
);
691 count_fsb
= imap
->br_blockcount
;
692 map_start_fsb
= imap
->br_startoff
;
694 XFS_STATS_ADD(mp
, xs_xstrat_bytes
, XFS_FSB_TO_B(mp
, count_fsb
));
696 while (count_fsb
!= 0) {
698 * Set up a transaction with which to allocate the
699 * backing store for the file. Do allocations in a
700 * loop until we get some space in the range we are
701 * interested in. The other space that might be allocated
702 * is in the delayed allocation extent on which we sit
703 * but before our buffer starts.
706 while (nimaps
== 0) {
707 nres
= XFS_EXTENTADD_SPACE_RES(mp
, XFS_DATA_FORK
);
709 * We have already reserved space for the extent and any
710 * indirect blocks when creating the delalloc extent,
711 * there is no need to reserve space in this transaction
714 error
= xfs_trans_alloc(mp
, &M_RES(mp
)->tr_write
, 0,
715 0, XFS_TRANS_RESERVE
, &tp
);
719 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
720 xfs_trans_ijoin(tp
, ip
, 0);
722 xfs_defer_init(&dfops
, &first_block
);
725 * it is possible that the extents have changed since
726 * we did the read call as we dropped the ilock for a
727 * while. We have to be careful about truncates or hole
728 * punchs here - we are not allowed to allocate
729 * non-delalloc blocks here.
731 * The only protection against truncation is the pages
732 * for the range we are being asked to convert are
733 * locked and hence a truncate will block on them
736 * As a result, if we go beyond the range we really
737 * need and hit an delalloc extent boundary followed by
738 * a hole while we have excess blocks in the map, we
739 * will fill the hole incorrectly and overrun the
740 * transaction reservation.
742 * Using a single map prevents this as we are forced to
743 * check each map we look for overlap with the desired
744 * range and abort as soon as we find it. Also, given
745 * that we only return a single map, having one beyond
746 * what we can return is probably a bit silly.
748 * We also need to check that we don't go beyond EOF;
749 * this is a truncate optimisation as a truncate sets
750 * the new file size before block on the pages we
751 * currently have locked under writeback. Because they
752 * are about to be tossed, we don't need to write them
756 end_fsb
= XFS_B_TO_FSB(mp
, XFS_ISIZE(ip
));
757 error
= xfs_bmap_last_offset(ip
, &last_block
,
762 last_block
= XFS_FILEOFF_MAX(last_block
, end_fsb
);
763 if ((map_start_fsb
+ count_fsb
) > last_block
) {
764 count_fsb
= last_block
- map_start_fsb
;
765 if (count_fsb
== 0) {
772 * From this point onwards we overwrite the imap
773 * pointer that the caller gave to us.
775 error
= xfs_bmapi_write(tp
, ip
, map_start_fsb
,
776 count_fsb
, 0, &first_block
,
782 error
= xfs_defer_finish(&tp
, &dfops
, NULL
);
786 error
= xfs_trans_commit(tp
);
790 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
794 * See if we were able to allocate an extent that
795 * covers at least part of the callers request
797 if (!(imap
->br_startblock
|| XFS_IS_REALTIME_INODE(ip
)))
798 return xfs_alert_fsblock_zero(ip
, imap
);
800 if ((offset_fsb
>= imap
->br_startoff
) &&
801 (offset_fsb
< (imap
->br_startoff
+
802 imap
->br_blockcount
))) {
803 XFS_STATS_INC(mp
, xs_xstrat_quick
);
808 * So far we have not mapped the requested part of the
809 * file, just surrounding data, try again.
811 count_fsb
-= imap
->br_blockcount
;
812 map_start_fsb
= imap
->br_startoff
+ imap
->br_blockcount
;
816 xfs_defer_cancel(&dfops
);
817 xfs_trans_cancel(tp
);
819 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
824 xfs_iomap_write_unwritten(
829 xfs_mount_t
*mp
= ip
->i_mount
;
830 xfs_fileoff_t offset_fsb
;
831 xfs_filblks_t count_fsb
;
832 xfs_filblks_t numblks_fsb
;
833 xfs_fsblock_t firstfsb
;
836 xfs_bmbt_irec_t imap
;
837 struct xfs_defer_ops dfops
;
842 trace_xfs_unwritten_convert(ip
, offset
, count
);
844 offset_fsb
= XFS_B_TO_FSBT(mp
, offset
);
845 count_fsb
= XFS_B_TO_FSB(mp
, (xfs_ufsize_t
)offset
+ count
);
846 count_fsb
= (xfs_filblks_t
)(count_fsb
- offset_fsb
);
849 * Reserve enough blocks in this transaction for two complete extent
850 * btree splits. We may be converting the middle part of an unwritten
851 * extent and in this case we will insert two new extents in the btree
852 * each of which could cause a full split.
854 * This reservation amount will be used in the first call to
855 * xfs_bmbt_split() to select an AG with enough space to satisfy the
856 * rest of the operation.
858 resblks
= XFS_DIOSTRAT_SPACE_RES(mp
, 0) << 1;
862 * Set up a transaction to convert the range of extents
863 * from unwritten to real. Do allocations in a loop until
864 * we have covered the range passed in.
866 * Note that we can't risk to recursing back into the filesystem
867 * here as we might be asked to write out the same inode that we
868 * complete here and might deadlock on the iolock.
870 error
= xfs_trans_alloc(mp
, &M_RES(mp
)->tr_write
, resblks
, 0,
871 XFS_TRANS_RESERVE
| XFS_TRANS_NOFS
, &tp
);
875 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
876 xfs_trans_ijoin(tp
, ip
, 0);
879 * Modify the unwritten extent state of the buffer.
881 xfs_defer_init(&dfops
, &firstfsb
);
883 error
= xfs_bmapi_write(tp
, ip
, offset_fsb
, count_fsb
,
884 XFS_BMAPI_CONVERT
, &firstfsb
, resblks
,
885 &imap
, &nimaps
, &dfops
);
887 goto error_on_bmapi_transaction
;
890 * Log the updated inode size as we go. We have to be careful
891 * to only log it up to the actual write offset if it is
892 * halfway into a block.
894 i_size
= XFS_FSB_TO_B(mp
, offset_fsb
+ count_fsb
);
895 if (i_size
> offset
+ count
)
896 i_size
= offset
+ count
;
898 i_size
= xfs_new_eof(ip
, i_size
);
900 ip
->i_d
.di_size
= i_size
;
901 xfs_trans_log_inode(tp
, ip
, XFS_ILOG_CORE
);
904 error
= xfs_defer_finish(&tp
, &dfops
, NULL
);
906 goto error_on_bmapi_transaction
;
908 error
= xfs_trans_commit(tp
);
909 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
913 if (!(imap
.br_startblock
|| XFS_IS_REALTIME_INODE(ip
)))
914 return xfs_alert_fsblock_zero(ip
, &imap
);
916 if ((numblks_fsb
= imap
.br_blockcount
) == 0) {
918 * The numblks_fsb value should always get
919 * smaller, otherwise the loop is stuck.
921 ASSERT(imap
.br_blockcount
);
924 offset_fsb
+= numblks_fsb
;
925 count_fsb
-= numblks_fsb
;
926 } while (count_fsb
> 0);
930 error_on_bmapi_transaction
:
931 xfs_defer_cancel(&dfops
);
932 xfs_trans_cancel(tp
);
933 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
937 static inline bool imap_needs_alloc(struct inode
*inode
,
938 struct xfs_bmbt_irec
*imap
, int nimaps
)
941 imap
->br_startblock
== HOLESTARTBLOCK
||
942 imap
->br_startblock
== DELAYSTARTBLOCK
||
943 (IS_DAX(inode
) && ISUNWRITTEN(imap
));
947 xfs_file_iomap_begin(
954 struct xfs_inode
*ip
= XFS_I(inode
);
955 struct xfs_mount
*mp
= ip
->i_mount
;
956 struct xfs_bmbt_irec imap
;
957 xfs_fileoff_t offset_fsb
, end_fsb
;
958 int nimaps
= 1, error
= 0;
961 if (XFS_FORCED_SHUTDOWN(mp
))
964 if ((flags
& IOMAP_WRITE
) &&
965 !IS_DAX(inode
) && !xfs_get_extsz_hint(ip
)) {
966 return xfs_file_iomap_begin_delay(inode
, offset
, length
, flags
,
970 lockmode
= xfs_ilock_data_map_shared(ip
);
972 ASSERT(offset
<= mp
->m_super
->s_maxbytes
);
973 if ((xfs_fsize_t
)offset
+ length
> mp
->m_super
->s_maxbytes
)
974 length
= mp
->m_super
->s_maxbytes
- offset
;
975 offset_fsb
= XFS_B_TO_FSBT(mp
, offset
);
976 end_fsb
= XFS_B_TO_FSB(mp
, offset
+ length
);
978 error
= xfs_bmapi_read(ip
, offset_fsb
, end_fsb
- offset_fsb
, &imap
,
979 &nimaps
, XFS_BMAPI_ENTIRE
);
981 xfs_iunlock(ip
, lockmode
);
985 if ((flags
& IOMAP_WRITE
) && imap_needs_alloc(inode
, &imap
, nimaps
)) {
987 * We cap the maximum length we map here to MAX_WRITEBACK_PAGES
988 * pages to keep the chunks of work done where somewhat symmetric
989 * with the work writeback does. This is a completely arbitrary
990 * number pulled out of thin air as a best guess for initial
993 * Note that the values needs to be less than 32-bits wide until
994 * the lower level functions are updated.
996 length
= min_t(loff_t
, length
, 1024 * PAGE_SIZE
);
998 * xfs_iomap_write_direct() expects the shared lock. It
999 * is unlocked on return.
1001 if (lockmode
== XFS_ILOCK_EXCL
)
1002 xfs_ilock_demote(ip
, lockmode
);
1003 error
= xfs_iomap_write_direct(ip
, offset
, length
, &imap
,
1008 iomap
->flags
= IOMAP_F_NEW
;
1009 trace_xfs_iomap_alloc(ip
, offset
, length
, 0, &imap
);
1013 xfs_iunlock(ip
, lockmode
);
1014 trace_xfs_iomap_found(ip
, offset
, length
, 0, &imap
);
1017 xfs_bmbt_to_iomap(ip
, iomap
, &imap
);
1022 xfs_file_iomap_end_delalloc(
1023 struct xfs_inode
*ip
,
1028 struct xfs_mount
*mp
= ip
->i_mount
;
1029 xfs_fileoff_t start_fsb
;
1030 xfs_fileoff_t end_fsb
;
1033 start_fsb
= XFS_B_TO_FSB(mp
, offset
+ written
);
1034 end_fsb
= XFS_B_TO_FSB(mp
, offset
+ length
);
1037 * Trim back delalloc blocks if we didn't manage to write the whole
1040 * We don't need to care about racing delalloc as we hold i_mutex
1041 * across the reserve/allocate/unreserve calls. If there are delalloc
1042 * blocks in the range, they are ours.
1044 if (start_fsb
< end_fsb
) {
1045 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
1046 error
= xfs_bmap_punch_delalloc_range(ip
, start_fsb
,
1047 end_fsb
- start_fsb
);
1048 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
1050 if (error
&& !XFS_FORCED_SHUTDOWN(mp
)) {
1051 xfs_alert(mp
, "%s: unable to clean up ino %lld",
1052 __func__
, ip
->i_ino
);
1062 struct inode
*inode
,
1067 struct iomap
*iomap
)
1069 if ((flags
& IOMAP_WRITE
) && iomap
->type
== IOMAP_DELALLOC
)
1070 return xfs_file_iomap_end_delalloc(XFS_I(inode
), offset
,
1075 struct iomap_ops xfs_iomap_ops
= {
1076 .iomap_begin
= xfs_file_iomap_begin
,
1077 .iomap_end
= xfs_file_iomap_end
,
1081 xfs_xattr_iomap_begin(
1082 struct inode
*inode
,
1086 struct iomap
*iomap
)
1088 struct xfs_inode
*ip
= XFS_I(inode
);
1089 struct xfs_mount
*mp
= ip
->i_mount
;
1090 xfs_fileoff_t offset_fsb
= XFS_B_TO_FSBT(mp
, offset
);
1091 xfs_fileoff_t end_fsb
= XFS_B_TO_FSB(mp
, offset
+ length
);
1092 struct xfs_bmbt_irec imap
;
1093 int nimaps
= 1, error
= 0;
1096 if (XFS_FORCED_SHUTDOWN(mp
))
1099 lockmode
= xfs_ilock_data_map_shared(ip
);
1101 /* if there are no attribute fork or extents, return ENOENT */
1102 if (XFS_IFORK_Q(ip
) || !ip
->i_d
.di_anextents
) {
1107 ASSERT(ip
->i_d
.di_aformat
!= XFS_DINODE_FMT_LOCAL
);
1108 error
= xfs_bmapi_read(ip
, offset_fsb
, end_fsb
- offset_fsb
, &imap
,
1109 &nimaps
, XFS_BMAPI_ENTIRE
| XFS_BMAPI_ATTRFORK
);
1111 xfs_iunlock(ip
, lockmode
);
1115 xfs_bmbt_to_iomap(ip
, iomap
, &imap
);
1121 struct iomap_ops xfs_xattr_iomap_ops
= {
1122 .iomap_begin
= xfs_xattr_iomap_begin
,