2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 #include "xfs_shared.h"
21 #include "xfs_format.h"
22 #include "xfs_log_format.h"
23 #include "xfs_trans_resv.h"
24 #include "xfs_mount.h"
25 #include "xfs_da_format.h"
26 #include "xfs_da_btree.h"
27 #include "xfs_inode.h"
28 #include "xfs_trans.h"
29 #include "xfs_inode_item.h"
31 #include "xfs_bmap_util.h"
32 #include "xfs_error.h"
34 #include "xfs_dir2_priv.h"
35 #include "xfs_ioctl.h"
36 #include "xfs_trace.h"
38 #include "xfs_icache.h"
41 #include <linux/dcache.h>
42 #include <linux/falloc.h>
43 #include <linux/pagevec.h>
45 static const struct vm_operations_struct xfs_file_vm_ops
;
48 * Locking primitives for read and write IO paths to ensure we consistently use
49 * and order the inode->i_mutex, ip->i_lock and ip->i_iolock.
56 if (type
& XFS_IOLOCK_EXCL
)
57 mutex_lock(&VFS_I(ip
)->i_mutex
);
66 xfs_iunlock(ip
, type
);
67 if (type
& XFS_IOLOCK_EXCL
)
68 mutex_unlock(&VFS_I(ip
)->i_mutex
);
76 xfs_ilock_demote(ip
, type
);
77 if (type
& XFS_IOLOCK_EXCL
)
78 mutex_unlock(&VFS_I(ip
)->i_mutex
);
84 * xfs_iozero clears the specified range of buffer supplied,
85 * and marks all the affected blocks as valid and modified. If
86 * an affected block is not allocated, it will be allocated. If
87 * an affected block is not completely overwritten, and is not
88 * valid before the operation, it will be read from disk before
89 * being partially zeroed.
93 struct xfs_inode
*ip
, /* inode */
94 loff_t pos
, /* offset in file */
95 size_t count
) /* size of data to zero */
98 struct address_space
*mapping
;
101 mapping
= VFS_I(ip
)->i_mapping
;
103 unsigned offset
, bytes
;
106 offset
= (pos
& (PAGE_CACHE_SIZE
-1)); /* Within page */
107 bytes
= PAGE_CACHE_SIZE
- offset
;
111 status
= pagecache_write_begin(NULL
, mapping
, pos
, bytes
,
112 AOP_FLAG_UNINTERRUPTIBLE
,
117 zero_user(page
, offset
, bytes
);
119 status
= pagecache_write_end(NULL
, mapping
, pos
, bytes
, bytes
,
121 WARN_ON(status
<= 0); /* can't return less than zero! */
131 xfs_update_prealloc_flags(
132 struct xfs_inode
*ip
,
133 enum xfs_prealloc_flags flags
)
135 struct xfs_trans
*tp
;
138 tp
= xfs_trans_alloc(ip
->i_mount
, XFS_TRANS_WRITEID
);
139 error
= xfs_trans_reserve(tp
, &M_RES(ip
->i_mount
)->tr_writeid
, 0, 0);
141 xfs_trans_cancel(tp
, 0);
145 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
146 xfs_trans_ijoin(tp
, ip
, XFS_ILOCK_EXCL
);
148 if (!(flags
& XFS_PREALLOC_INVISIBLE
)) {
149 ip
->i_d
.di_mode
&= ~S_ISUID
;
150 if (ip
->i_d
.di_mode
& S_IXGRP
)
151 ip
->i_d
.di_mode
&= ~S_ISGID
;
152 xfs_trans_ichgtime(tp
, ip
, XFS_ICHGTIME_MOD
| XFS_ICHGTIME_CHG
);
155 if (flags
& XFS_PREALLOC_SET
)
156 ip
->i_d
.di_flags
|= XFS_DIFLAG_PREALLOC
;
157 if (flags
& XFS_PREALLOC_CLEAR
)
158 ip
->i_d
.di_flags
&= ~XFS_DIFLAG_PREALLOC
;
160 xfs_trans_log_inode(tp
, ip
, XFS_ILOG_CORE
);
161 if (flags
& XFS_PREALLOC_SYNC
)
162 xfs_trans_set_sync(tp
);
163 return xfs_trans_commit(tp
, 0);
167 * Fsync operations on directories are much simpler than on regular files,
168 * as there is no file data to flush, and thus also no need for explicit
169 * cache flush operations, and there are no non-transaction metadata updates
170 * on directories either.
179 struct xfs_inode
*ip
= XFS_I(file
->f_mapping
->host
);
180 struct xfs_mount
*mp
= ip
->i_mount
;
183 trace_xfs_dir_fsync(ip
);
185 xfs_ilock(ip
, XFS_ILOCK_SHARED
);
186 if (xfs_ipincount(ip
))
187 lsn
= ip
->i_itemp
->ili_last_lsn
;
188 xfs_iunlock(ip
, XFS_ILOCK_SHARED
);
192 return _xfs_log_force_lsn(mp
, lsn
, XFS_LOG_SYNC
, NULL
);
202 struct inode
*inode
= file
->f_mapping
->host
;
203 struct xfs_inode
*ip
= XFS_I(inode
);
204 struct xfs_mount
*mp
= ip
->i_mount
;
209 trace_xfs_file_fsync(ip
);
211 error
= filemap_write_and_wait_range(inode
->i_mapping
, start
, end
);
215 if (XFS_FORCED_SHUTDOWN(mp
))
218 xfs_iflags_clear(ip
, XFS_ITRUNCATED
);
220 if (mp
->m_flags
& XFS_MOUNT_BARRIER
) {
222 * If we have an RT and/or log subvolume we need to make sure
223 * to flush the write cache the device used for file data
224 * first. This is to ensure newly written file data make
225 * it to disk before logging the new inode size in case of
226 * an extending write.
228 if (XFS_IS_REALTIME_INODE(ip
))
229 xfs_blkdev_issue_flush(mp
->m_rtdev_targp
);
230 else if (mp
->m_logdev_targp
!= mp
->m_ddev_targp
)
231 xfs_blkdev_issue_flush(mp
->m_ddev_targp
);
235 * All metadata updates are logged, which means that we just have
236 * to flush the log up to the latest LSN that touched the inode.
238 xfs_ilock(ip
, XFS_ILOCK_SHARED
);
239 if (xfs_ipincount(ip
)) {
241 (ip
->i_itemp
->ili_fields
& ~XFS_ILOG_TIMESTAMP
))
242 lsn
= ip
->i_itemp
->ili_last_lsn
;
244 xfs_iunlock(ip
, XFS_ILOCK_SHARED
);
247 error
= _xfs_log_force_lsn(mp
, lsn
, XFS_LOG_SYNC
, &log_flushed
);
250 * If we only have a single device, and the log force about was
251 * a no-op we might have to flush the data device cache here.
252 * This can only happen for fdatasync/O_DSYNC if we were overwriting
253 * an already allocated file and thus do not have any metadata to
256 if ((mp
->m_flags
& XFS_MOUNT_BARRIER
) &&
257 mp
->m_logdev_targp
== mp
->m_ddev_targp
&&
258 !XFS_IS_REALTIME_INODE(ip
) &&
260 xfs_blkdev_issue_flush(mp
->m_ddev_targp
);
270 struct file
*file
= iocb
->ki_filp
;
271 struct inode
*inode
= file
->f_mapping
->host
;
272 struct xfs_inode
*ip
= XFS_I(inode
);
273 struct xfs_mount
*mp
= ip
->i_mount
;
274 size_t size
= iov_iter_count(to
);
278 loff_t pos
= iocb
->ki_pos
;
280 XFS_STATS_INC(xs_read_calls
);
282 if (unlikely(iocb
->ki_flags
& IOCB_DIRECT
))
283 ioflags
|= XFS_IO_ISDIRECT
;
284 if (file
->f_mode
& FMODE_NOCMTIME
)
285 ioflags
|= XFS_IO_INVIS
;
287 if (unlikely(ioflags
& XFS_IO_ISDIRECT
)) {
288 xfs_buftarg_t
*target
=
289 XFS_IS_REALTIME_INODE(ip
) ?
290 mp
->m_rtdev_targp
: mp
->m_ddev_targp
;
291 /* DIO must be aligned to device logical sector size */
292 if ((pos
| size
) & target
->bt_logical_sectormask
) {
293 if (pos
== i_size_read(inode
))
299 n
= mp
->m_super
->s_maxbytes
- pos
;
300 if (n
<= 0 || size
== 0)
306 if (XFS_FORCED_SHUTDOWN(mp
))
310 * Locking is a bit tricky here. If we take an exclusive lock
311 * for direct IO, we effectively serialise all new concurrent
312 * read IO to this file and block it behind IO that is currently in
313 * progress because IO in progress holds the IO lock shared. We only
314 * need to hold the lock exclusive to blow away the page cache, so
315 * only take lock exclusively if the page cache needs invalidation.
316 * This allows the normal direct IO case of no page cache pages to
317 * proceeed concurrently without serialisation.
319 xfs_rw_ilock(ip
, XFS_IOLOCK_SHARED
);
320 if ((ioflags
& XFS_IO_ISDIRECT
) && inode
->i_mapping
->nrpages
) {
321 xfs_rw_iunlock(ip
, XFS_IOLOCK_SHARED
);
322 xfs_rw_ilock(ip
, XFS_IOLOCK_EXCL
);
324 if (inode
->i_mapping
->nrpages
) {
325 ret
= filemap_write_and_wait_range(
326 VFS_I(ip
)->i_mapping
,
327 pos
, pos
+ size
- 1);
329 xfs_rw_iunlock(ip
, XFS_IOLOCK_EXCL
);
334 * Invalidate whole pages. This can return an error if
335 * we fail to invalidate a page, but this should never
336 * happen on XFS. Warn if it does fail.
338 ret
= invalidate_inode_pages2_range(VFS_I(ip
)->i_mapping
,
339 pos
>> PAGE_CACHE_SHIFT
,
340 (pos
+ size
- 1) >> PAGE_CACHE_SHIFT
);
344 xfs_rw_ilock_demote(ip
, XFS_IOLOCK_EXCL
);
347 trace_xfs_file_read(ip
, size
, pos
, ioflags
);
349 ret
= generic_file_read_iter(iocb
, to
);
351 XFS_STATS_ADD(xs_read_bytes
, ret
);
353 xfs_rw_iunlock(ip
, XFS_IOLOCK_SHARED
);
358 xfs_file_splice_read(
361 struct pipe_inode_info
*pipe
,
365 struct xfs_inode
*ip
= XFS_I(infilp
->f_mapping
->host
);
369 XFS_STATS_INC(xs_read_calls
);
371 if (infilp
->f_mode
& FMODE_NOCMTIME
)
372 ioflags
|= XFS_IO_INVIS
;
374 if (XFS_FORCED_SHUTDOWN(ip
->i_mount
))
377 xfs_rw_ilock(ip
, XFS_IOLOCK_SHARED
);
379 trace_xfs_file_splice_read(ip
, count
, *ppos
, ioflags
);
381 ret
= generic_file_splice_read(infilp
, ppos
, pipe
, count
, flags
);
383 XFS_STATS_ADD(xs_read_bytes
, ret
);
385 xfs_rw_iunlock(ip
, XFS_IOLOCK_SHARED
);
390 * This routine is called to handle zeroing any space in the last block of the
391 * file that is beyond the EOF. We do this since the size is being increased
392 * without writing anything to that block and we don't want to read the
393 * garbage on the disk.
395 STATIC
int /* error (positive) */
397 struct xfs_inode
*ip
,
402 struct xfs_mount
*mp
= ip
->i_mount
;
403 xfs_fileoff_t last_fsb
= XFS_B_TO_FSBT(mp
, isize
);
404 int zero_offset
= XFS_B_FSB_OFFSET(mp
, isize
);
408 struct xfs_bmbt_irec imap
;
410 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
411 error
= xfs_bmapi_read(ip
, last_fsb
, 1, &imap
, &nimaps
, 0);
412 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
419 * If the block underlying isize is just a hole, then there
420 * is nothing to zero.
422 if (imap
.br_startblock
== HOLESTARTBLOCK
)
425 zero_len
= mp
->m_sb
.sb_blocksize
- zero_offset
;
426 if (isize
+ zero_len
> offset
)
427 zero_len
= offset
- isize
;
429 return xfs_iozero(ip
, isize
, zero_len
);
433 * Zero any on disk space between the current EOF and the new, larger EOF.
435 * This handles the normal case of zeroing the remainder of the last block in
436 * the file and the unusual case of zeroing blocks out beyond the size of the
437 * file. This second case only happens with fixed size extents and when the
438 * system crashes before the inode size was updated but after blocks were
441 * Expects the iolock to be held exclusive, and will take the ilock internally.
443 int /* error (positive) */
445 struct xfs_inode
*ip
,
446 xfs_off_t offset
, /* starting I/O offset */
447 xfs_fsize_t isize
, /* current inode size */
450 struct xfs_mount
*mp
= ip
->i_mount
;
451 xfs_fileoff_t start_zero_fsb
;
452 xfs_fileoff_t end_zero_fsb
;
453 xfs_fileoff_t zero_count_fsb
;
454 xfs_fileoff_t last_fsb
;
455 xfs_fileoff_t zero_off
;
456 xfs_fsize_t zero_len
;
459 struct xfs_bmbt_irec imap
;
461 ASSERT(xfs_isilocked(ip
, XFS_IOLOCK_EXCL
));
462 ASSERT(offset
> isize
);
465 * First handle zeroing the block on which isize resides.
467 * We only zero a part of that block so it is handled specially.
469 if (XFS_B_FSB_OFFSET(mp
, isize
) != 0) {
470 error
= xfs_zero_last_block(ip
, offset
, isize
, did_zeroing
);
476 * Calculate the range between the new size and the old where blocks
477 * needing to be zeroed may exist.
479 * To get the block where the last byte in the file currently resides,
480 * we need to subtract one from the size and truncate back to a block
481 * boundary. We subtract 1 in case the size is exactly on a block
484 last_fsb
= isize
? XFS_B_TO_FSBT(mp
, isize
- 1) : (xfs_fileoff_t
)-1;
485 start_zero_fsb
= XFS_B_TO_FSB(mp
, (xfs_ufsize_t
)isize
);
486 end_zero_fsb
= XFS_B_TO_FSBT(mp
, offset
- 1);
487 ASSERT((xfs_sfiloff_t
)last_fsb
< (xfs_sfiloff_t
)start_zero_fsb
);
488 if (last_fsb
== end_zero_fsb
) {
490 * The size was only incremented on its last block.
491 * We took care of that above, so just return.
496 ASSERT(start_zero_fsb
<= end_zero_fsb
);
497 while (start_zero_fsb
<= end_zero_fsb
) {
499 zero_count_fsb
= end_zero_fsb
- start_zero_fsb
+ 1;
501 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
502 error
= xfs_bmapi_read(ip
, start_zero_fsb
, zero_count_fsb
,
504 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
510 if (imap
.br_state
== XFS_EXT_UNWRITTEN
||
511 imap
.br_startblock
== HOLESTARTBLOCK
) {
512 start_zero_fsb
= imap
.br_startoff
+ imap
.br_blockcount
;
513 ASSERT(start_zero_fsb
<= (end_zero_fsb
+ 1));
518 * There are blocks we need to zero.
520 zero_off
= XFS_FSB_TO_B(mp
, start_zero_fsb
);
521 zero_len
= XFS_FSB_TO_B(mp
, imap
.br_blockcount
);
523 if ((zero_off
+ zero_len
) > offset
)
524 zero_len
= offset
- zero_off
;
526 error
= xfs_iozero(ip
, zero_off
, zero_len
);
531 start_zero_fsb
= imap
.br_startoff
+ imap
.br_blockcount
;
532 ASSERT(start_zero_fsb
<= (end_zero_fsb
+ 1));
539 * Common pre-write limit and setup checks.
541 * Called with the iolocked held either shared and exclusive according to
542 * @iolock, and returns with it held. Might upgrade the iolock to exclusive
543 * if called for a direct write beyond i_size.
546 xfs_file_aio_write_checks(
548 struct iov_iter
*from
,
551 struct file
*file
= iocb
->ki_filp
;
552 struct inode
*inode
= file
->f_mapping
->host
;
553 struct xfs_inode
*ip
= XFS_I(inode
);
555 size_t count
= iov_iter_count(from
);
558 error
= generic_write_checks(iocb
, from
);
562 error
= xfs_break_layouts(inode
, iolock
, true);
567 * If the offset is beyond the size of the file, we need to zero any
568 * blocks that fall between the existing EOF and the start of this
569 * write. If zeroing is needed and we are currently holding the
570 * iolock shared, we need to update it to exclusive which implies
571 * having to redo all checks before.
573 * We need to serialise against EOF updates that occur in IO
574 * completions here. We want to make sure that nobody is changing the
575 * size while we do this check until we have placed an IO barrier (i.e.
576 * hold the XFS_IOLOCK_EXCL) that prevents new IO from being dispatched.
577 * The spinlock effectively forms a memory barrier once we have the
578 * XFS_IOLOCK_EXCL so we are guaranteed to see the latest EOF value
579 * and hence be able to correctly determine if we need to run zeroing.
581 spin_lock(&ip
->i_flags_lock
);
582 if (iocb
->ki_pos
> i_size_read(inode
)) {
585 spin_unlock(&ip
->i_flags_lock
);
586 if (*iolock
== XFS_IOLOCK_SHARED
) {
587 xfs_rw_iunlock(ip
, *iolock
);
588 *iolock
= XFS_IOLOCK_EXCL
;
589 xfs_rw_ilock(ip
, *iolock
);
590 iov_iter_reexpand(from
, count
);
593 * We now have an IO submission barrier in place, but
594 * AIO can do EOF updates during IO completion and hence
595 * we now need to wait for all of them to drain. Non-AIO
596 * DIO will have drained before we are given the
597 * XFS_IOLOCK_EXCL, and so for most cases this wait is a
600 inode_dio_wait(inode
);
603 error
= xfs_zero_eof(ip
, iocb
->ki_pos
, i_size_read(inode
), &zero
);
607 spin_unlock(&ip
->i_flags_lock
);
610 * Updating the timestamps will grab the ilock again from
611 * xfs_fs_dirty_inode, so we have to call it after dropping the
612 * lock above. Eventually we should look into a way to avoid
613 * the pointless lock roundtrip.
615 if (likely(!(file
->f_mode
& FMODE_NOCMTIME
))) {
616 error
= file_update_time(file
);
622 * If we're writing the file then make sure to clear the setuid and
623 * setgid bits if the process is not being run by root. This keeps
624 * people from modifying setuid and setgid binaries.
626 return file_remove_suid(file
);
630 * xfs_file_dio_aio_write - handle direct IO writes
632 * Lock the inode appropriately to prepare for and issue a direct IO write.
633 * By separating it from the buffered write path we remove all the tricky to
634 * follow locking changes and looping.
636 * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
637 * until we're sure the bytes at the new EOF have been zeroed and/or the cached
638 * pages are flushed out.
640 * In most cases the direct IO writes will be done holding IOLOCK_SHARED
641 * allowing them to be done in parallel with reads and other direct IO writes.
642 * However, if the IO is not aligned to filesystem blocks, the direct IO layer
643 * needs to do sub-block zeroing and that requires serialisation against other
644 * direct IOs to the same block. In this case we need to serialise the
645 * submission of the unaligned IOs so that we don't get racing block zeroing in
646 * the dio layer. To avoid the problem with aio, we also need to wait for
647 * outstanding IOs to complete so that unwritten extent conversion is completed
648 * before we try to map the overlapping block. This is currently implemented by
649 * hitting it with a big hammer (i.e. inode_dio_wait()).
651 * Returns with locks held indicated by @iolock and errors indicated by
652 * negative return values.
655 xfs_file_dio_aio_write(
657 struct iov_iter
*from
)
659 struct file
*file
= iocb
->ki_filp
;
660 struct address_space
*mapping
= file
->f_mapping
;
661 struct inode
*inode
= mapping
->host
;
662 struct xfs_inode
*ip
= XFS_I(inode
);
663 struct xfs_mount
*mp
= ip
->i_mount
;
665 int unaligned_io
= 0;
667 size_t count
= iov_iter_count(from
);
668 loff_t pos
= iocb
->ki_pos
;
670 struct iov_iter data
;
671 struct xfs_buftarg
*target
= XFS_IS_REALTIME_INODE(ip
) ?
672 mp
->m_rtdev_targp
: mp
->m_ddev_targp
;
674 /* DIO must be aligned to device logical sector size */
675 if ((pos
| count
) & target
->bt_logical_sectormask
)
678 /* "unaligned" here means not aligned to a filesystem block */
679 if ((pos
& mp
->m_blockmask
) || ((pos
+ count
) & mp
->m_blockmask
))
683 * We don't need to take an exclusive lock unless there page cache needs
684 * to be invalidated or unaligned IO is being executed. We don't need to
685 * consider the EOF extension case here because
686 * xfs_file_aio_write_checks() will relock the inode as necessary for
687 * EOF zeroing cases and fill out the new inode size as appropriate.
689 if (unaligned_io
|| mapping
->nrpages
)
690 iolock
= XFS_IOLOCK_EXCL
;
692 iolock
= XFS_IOLOCK_SHARED
;
693 xfs_rw_ilock(ip
, iolock
);
696 * Recheck if there are cached pages that need invalidate after we got
697 * the iolock to protect against other threads adding new pages while
698 * we were waiting for the iolock.
700 if (mapping
->nrpages
&& iolock
== XFS_IOLOCK_SHARED
) {
701 xfs_rw_iunlock(ip
, iolock
);
702 iolock
= XFS_IOLOCK_EXCL
;
703 xfs_rw_ilock(ip
, iolock
);
706 ret
= xfs_file_aio_write_checks(iocb
, from
, &iolock
);
709 count
= iov_iter_count(from
);
711 end
= pos
+ count
- 1;
713 if (mapping
->nrpages
) {
714 ret
= filemap_write_and_wait_range(VFS_I(ip
)->i_mapping
,
719 * Invalidate whole pages. This can return an error if
720 * we fail to invalidate a page, but this should never
721 * happen on XFS. Warn if it does fail.
723 ret
= invalidate_inode_pages2_range(VFS_I(ip
)->i_mapping
,
724 pos
>> PAGE_CACHE_SHIFT
,
725 end
>> PAGE_CACHE_SHIFT
);
731 * If we are doing unaligned IO, wait for all other IO to drain,
732 * otherwise demote the lock if we had to flush cached pages
735 inode_dio_wait(inode
);
736 else if (iolock
== XFS_IOLOCK_EXCL
) {
737 xfs_rw_ilock_demote(ip
, XFS_IOLOCK_EXCL
);
738 iolock
= XFS_IOLOCK_SHARED
;
741 trace_xfs_file_direct_write(ip
, count
, iocb
->ki_pos
, 0);
744 ret
= mapping
->a_ops
->direct_IO(iocb
, &data
, pos
);
746 /* see generic_file_direct_write() for why this is necessary */
747 if (mapping
->nrpages
) {
748 invalidate_inode_pages2_range(mapping
,
749 pos
>> PAGE_CACHE_SHIFT
,
750 end
>> PAGE_CACHE_SHIFT
);
755 iov_iter_advance(from
, ret
);
759 xfs_rw_iunlock(ip
, iolock
);
761 /* No fallback to buffered IO on errors for XFS. */
762 ASSERT(ret
< 0 || ret
== count
);
767 xfs_file_buffered_aio_write(
769 struct iov_iter
*from
)
771 struct file
*file
= iocb
->ki_filp
;
772 struct address_space
*mapping
= file
->f_mapping
;
773 struct inode
*inode
= mapping
->host
;
774 struct xfs_inode
*ip
= XFS_I(inode
);
777 int iolock
= XFS_IOLOCK_EXCL
;
779 xfs_rw_ilock(ip
, iolock
);
781 ret
= xfs_file_aio_write_checks(iocb
, from
, &iolock
);
785 /* We can write back this queue in page reclaim */
786 current
->backing_dev_info
= inode_to_bdi(inode
);
789 trace_xfs_file_buffered_write(ip
, iov_iter_count(from
),
791 ret
= generic_perform_write(file
, from
, iocb
->ki_pos
);
792 if (likely(ret
>= 0))
796 * If we hit a space limit, try to free up some lingering preallocated
797 * space before returning an error. In the case of ENOSPC, first try to
798 * write back all dirty inodes to free up some of the excess reserved
799 * metadata space. This reduces the chances that the eofblocks scan
800 * waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
801 * also behaves as a filter to prevent too many eofblocks scans from
802 * running at the same time.
804 if (ret
== -EDQUOT
&& !enospc
) {
805 enospc
= xfs_inode_free_quota_eofblocks(ip
);
808 } else if (ret
== -ENOSPC
&& !enospc
) {
809 struct xfs_eofblocks eofb
= {0};
812 xfs_flush_inodes(ip
->i_mount
);
813 eofb
.eof_scan_owner
= ip
->i_ino
; /* for locking */
814 eofb
.eof_flags
= XFS_EOF_FLAGS_SYNC
;
815 xfs_icache_free_eofblocks(ip
->i_mount
, &eofb
);
819 current
->backing_dev_info
= NULL
;
821 xfs_rw_iunlock(ip
, iolock
);
828 struct iov_iter
*from
)
830 struct file
*file
= iocb
->ki_filp
;
831 struct address_space
*mapping
= file
->f_mapping
;
832 struct inode
*inode
= mapping
->host
;
833 struct xfs_inode
*ip
= XFS_I(inode
);
835 size_t ocount
= iov_iter_count(from
);
837 XFS_STATS_INC(xs_write_calls
);
842 if (XFS_FORCED_SHUTDOWN(ip
->i_mount
))
845 if (unlikely(iocb
->ki_flags
& IOCB_DIRECT
))
846 ret
= xfs_file_dio_aio_write(iocb
, from
);
848 ret
= xfs_file_buffered_aio_write(iocb
, from
);
853 XFS_STATS_ADD(xs_write_bytes
, ret
);
855 /* Handle various SYNC-type writes */
856 err
= generic_write_sync(file
, iocb
->ki_pos
- ret
, ret
);
863 #define XFS_FALLOC_FL_SUPPORTED \
864 (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
865 FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
866 FALLOC_FL_INSERT_RANGE)
875 struct inode
*inode
= file_inode(file
);
876 struct xfs_inode
*ip
= XFS_I(inode
);
878 enum xfs_prealloc_flags flags
= 0;
879 uint iolock
= XFS_IOLOCK_EXCL
;
881 bool do_file_insert
= 0;
883 if (!S_ISREG(inode
->i_mode
))
885 if (mode
& ~XFS_FALLOC_FL_SUPPORTED
)
888 xfs_ilock(ip
, iolock
);
889 error
= xfs_break_layouts(inode
, &iolock
, false);
893 xfs_ilock(ip
, XFS_MMAPLOCK_EXCL
);
894 iolock
|= XFS_MMAPLOCK_EXCL
;
896 if (mode
& FALLOC_FL_PUNCH_HOLE
) {
897 error
= xfs_free_file_space(ip
, offset
, len
);
900 } else if (mode
& FALLOC_FL_COLLAPSE_RANGE
) {
901 unsigned blksize_mask
= (1 << inode
->i_blkbits
) - 1;
903 if (offset
& blksize_mask
|| len
& blksize_mask
) {
909 * There is no need to overlap collapse range with EOF,
910 * in which case it is effectively a truncate operation
912 if (offset
+ len
>= i_size_read(inode
)) {
917 new_size
= i_size_read(inode
) - len
;
919 error
= xfs_collapse_file_space(ip
, offset
, len
);
922 } else if (mode
& FALLOC_FL_INSERT_RANGE
) {
923 unsigned blksize_mask
= (1 << inode
->i_blkbits
) - 1;
925 new_size
= i_size_read(inode
) + len
;
926 if (offset
& blksize_mask
|| len
& blksize_mask
) {
931 /* check the new inode size does not wrap through zero */
932 if (new_size
> inode
->i_sb
->s_maxbytes
) {
937 /* Offset should be less than i_size */
938 if (offset
>= i_size_read(inode
)) {
944 flags
|= XFS_PREALLOC_SET
;
946 if (!(mode
& FALLOC_FL_KEEP_SIZE
) &&
947 offset
+ len
> i_size_read(inode
)) {
948 new_size
= offset
+ len
;
949 error
= inode_newsize_ok(inode
, new_size
);
954 if (mode
& FALLOC_FL_ZERO_RANGE
)
955 error
= xfs_zero_file_space(ip
, offset
, len
);
957 error
= xfs_alloc_file_space(ip
, offset
, len
,
963 if (file
->f_flags
& O_DSYNC
)
964 flags
|= XFS_PREALLOC_SYNC
;
966 error
= xfs_update_prealloc_flags(ip
, flags
);
970 /* Change file size if needed */
974 iattr
.ia_valid
= ATTR_SIZE
;
975 iattr
.ia_size
= new_size
;
976 error
= xfs_setattr_size(ip
, &iattr
);
982 * Perform hole insertion now that the file size has been
983 * updated so that if we crash during the operation we don't
984 * leave shifted extents past EOF and hence losing access to
985 * the data that is contained within them.
988 error
= xfs_insert_file_space(ip
, offset
, len
);
991 xfs_iunlock(ip
, iolock
);
1001 if (!(file
->f_flags
& O_LARGEFILE
) && i_size_read(inode
) > MAX_NON_LFS
)
1003 if (XFS_FORCED_SHUTDOWN(XFS_M(inode
->i_sb
)))
1010 struct inode
*inode
,
1013 struct xfs_inode
*ip
= XFS_I(inode
);
1017 error
= xfs_file_open(inode
, file
);
1022 * If there are any blocks, read-ahead block 0 as we're almost
1023 * certain to have the next operation be a read there.
1025 mode
= xfs_ilock_data_map_shared(ip
);
1026 if (ip
->i_d
.di_nextents
> 0)
1027 xfs_dir3_data_readahead(ip
, 0, -1);
1028 xfs_iunlock(ip
, mode
);
1034 struct inode
*inode
,
1037 return xfs_release(XFS_I(inode
));
1043 struct dir_context
*ctx
)
1045 struct inode
*inode
= file_inode(file
);
1046 xfs_inode_t
*ip
= XFS_I(inode
);
1050 * The Linux API doesn't pass down the total size of the buffer
1051 * we read into down to the filesystem. With the filldir concept
1052 * it's not needed for correct information, but the XFS dir2 leaf
1053 * code wants an estimate of the buffer size to calculate it's
1054 * readahead window and size the buffers used for mapping to
1057 * Try to give it an estimate that's good enough, maybe at some
1058 * point we can change the ->readdir prototype to include the
1059 * buffer size. For now we use the current glibc buffer size.
1061 bufsize
= (size_t)min_t(loff_t
, 32768, ip
->i_d
.di_size
);
1063 return xfs_readdir(ip
, ctx
, bufsize
);
1069 struct vm_area_struct
*vma
)
1071 vma
->vm_ops
= &xfs_file_vm_ops
;
1073 file_accessed(filp
);
1078 * This type is designed to indicate the type of offset we would like
1079 * to search from page cache for xfs_seek_hole_data().
1087 * Lookup the desired type of offset from the given page.
1089 * On success, return true and the offset argument will point to the
1090 * start of the region that was found. Otherwise this function will
1091 * return false and keep the offset argument unchanged.
1094 xfs_lookup_buffer_offset(
1099 loff_t lastoff
= page_offset(page
);
1101 struct buffer_head
*bh
, *head
;
1103 bh
= head
= page_buffers(page
);
1106 * Unwritten extents that have data in the page
1107 * cache covering them can be identified by the
1108 * BH_Unwritten state flag. Pages with multiple
1109 * buffers might have a mix of holes, data and
1110 * unwritten extents - any buffer with valid
1111 * data in it should have BH_Uptodate flag set
1114 if (buffer_unwritten(bh
) ||
1115 buffer_uptodate(bh
)) {
1116 if (type
== DATA_OFF
)
1119 if (type
== HOLE_OFF
)
1127 lastoff
+= bh
->b_size
;
1128 } while ((bh
= bh
->b_this_page
) != head
);
1134 * This routine is called to find out and return a data or hole offset
1135 * from the page cache for unwritten extents according to the desired
1136 * type for xfs_seek_hole_data().
1138 * The argument offset is used to tell where we start to search from the
1139 * page cache. Map is used to figure out the end points of the range to
1142 * Return true if the desired type of offset was found, and the argument
1143 * offset is filled with that address. Otherwise, return false and keep
1147 xfs_find_get_desired_pgoff(
1148 struct inode
*inode
,
1149 struct xfs_bmbt_irec
*map
,
1153 struct xfs_inode
*ip
= XFS_I(inode
);
1154 struct xfs_mount
*mp
= ip
->i_mount
;
1155 struct pagevec pvec
;
1159 loff_t startoff
= *offset
;
1160 loff_t lastoff
= startoff
;
1163 pagevec_init(&pvec
, 0);
1165 index
= startoff
>> PAGE_CACHE_SHIFT
;
1166 endoff
= XFS_FSB_TO_B(mp
, map
->br_startoff
+ map
->br_blockcount
);
1167 end
= endoff
>> PAGE_CACHE_SHIFT
;
1173 want
= min_t(pgoff_t
, end
- index
, PAGEVEC_SIZE
);
1174 nr_pages
= pagevec_lookup(&pvec
, inode
->i_mapping
, index
,
1177 * No page mapped into given range. If we are searching holes
1178 * and if this is the first time we got into the loop, it means
1179 * that the given offset is landed in a hole, return it.
1181 * If we have already stepped through some block buffers to find
1182 * holes but they all contains data. In this case, the last
1183 * offset is already updated and pointed to the end of the last
1184 * mapped page, if it does not reach the endpoint to search,
1185 * that means there should be a hole between them.
1187 if (nr_pages
== 0) {
1188 /* Data search found nothing */
1189 if (type
== DATA_OFF
)
1192 ASSERT(type
== HOLE_OFF
);
1193 if (lastoff
== startoff
|| lastoff
< endoff
) {
1201 * At lease we found one page. If this is the first time we
1202 * step into the loop, and if the first page index offset is
1203 * greater than the given search offset, a hole was found.
1205 if (type
== HOLE_OFF
&& lastoff
== startoff
&&
1206 lastoff
< page_offset(pvec
.pages
[0])) {
1211 for (i
= 0; i
< nr_pages
; i
++) {
1212 struct page
*page
= pvec
.pages
[i
];
1216 * At this point, the page may be truncated or
1217 * invalidated (changing page->mapping to NULL),
1218 * or even swizzled back from swapper_space to tmpfs
1219 * file mapping. However, page->index will not change
1220 * because we have a reference on the page.
1222 * Searching done if the page index is out of range.
1223 * If the current offset is not reaches the end of
1224 * the specified search range, there should be a hole
1227 if (page
->index
> end
) {
1228 if (type
== HOLE_OFF
&& lastoff
< endoff
) {
1237 * Page truncated or invalidated(page->mapping == NULL).
1238 * We can freely skip it and proceed to check the next
1241 if (unlikely(page
->mapping
!= inode
->i_mapping
)) {
1246 if (!page_has_buffers(page
)) {
1251 found
= xfs_lookup_buffer_offset(page
, &b_offset
, type
);
1254 * The found offset may be less than the start
1255 * point to search if this is the first time to
1258 *offset
= max_t(loff_t
, startoff
, b_offset
);
1264 * We either searching data but nothing was found, or
1265 * searching hole but found a data buffer. In either
1266 * case, probably the next page contains the desired
1267 * things, update the last offset to it so.
1269 lastoff
= page_offset(page
) + PAGE_SIZE
;
1274 * The number of returned pages less than our desired, search
1275 * done. In this case, nothing was found for searching data,
1276 * but we found a hole behind the last offset.
1278 if (nr_pages
< want
) {
1279 if (type
== HOLE_OFF
) {
1286 index
= pvec
.pages
[i
- 1]->index
+ 1;
1287 pagevec_release(&pvec
);
1288 } while (index
<= end
);
1291 pagevec_release(&pvec
);
1301 struct inode
*inode
= file
->f_mapping
->host
;
1302 struct xfs_inode
*ip
= XFS_I(inode
);
1303 struct xfs_mount
*mp
= ip
->i_mount
;
1304 loff_t
uninitialized_var(offset
);
1306 xfs_fileoff_t fsbno
;
1311 if (XFS_FORCED_SHUTDOWN(mp
))
1314 lock
= xfs_ilock_data_map_shared(ip
);
1316 isize
= i_size_read(inode
);
1317 if (start
>= isize
) {
1323 * Try to read extents from the first block indicated
1324 * by fsbno to the end block of the file.
1326 fsbno
= XFS_B_TO_FSBT(mp
, start
);
1327 end
= XFS_B_TO_FSB(mp
, isize
);
1330 struct xfs_bmbt_irec map
[2];
1334 error
= xfs_bmapi_read(ip
, fsbno
, end
- fsbno
, map
, &nmap
,
1339 /* No extents at given offset, must be beyond EOF */
1345 for (i
= 0; i
< nmap
; i
++) {
1346 offset
= max_t(loff_t
, start
,
1347 XFS_FSB_TO_B(mp
, map
[i
].br_startoff
));
1349 /* Landed in the hole we wanted? */
1350 if (whence
== SEEK_HOLE
&&
1351 map
[i
].br_startblock
== HOLESTARTBLOCK
)
1354 /* Landed in the data extent we wanted? */
1355 if (whence
== SEEK_DATA
&&
1356 (map
[i
].br_startblock
== DELAYSTARTBLOCK
||
1357 (map
[i
].br_state
== XFS_EXT_NORM
&&
1358 !isnullstartblock(map
[i
].br_startblock
))))
1362 * Landed in an unwritten extent, try to search
1363 * for hole or data from page cache.
1365 if (map
[i
].br_state
== XFS_EXT_UNWRITTEN
) {
1366 if (xfs_find_get_desired_pgoff(inode
, &map
[i
],
1367 whence
== SEEK_HOLE
? HOLE_OFF
: DATA_OFF
,
1374 * We only received one extent out of the two requested. This
1375 * means we've hit EOF and didn't find what we are looking for.
1379 * If we were looking for a hole, set offset to
1380 * the end of the file (i.e., there is an implicit
1381 * hole at the end of any file).
1383 if (whence
== SEEK_HOLE
) {
1388 * If we were looking for data, it's nowhere to be found
1390 ASSERT(whence
== SEEK_DATA
);
1398 * Nothing was found, proceed to the next round of search
1399 * if the next reading offset is not at or beyond EOF.
1401 fsbno
= map
[i
- 1].br_startoff
+ map
[i
- 1].br_blockcount
;
1402 start
= XFS_FSB_TO_B(mp
, fsbno
);
1403 if (start
>= isize
) {
1404 if (whence
== SEEK_HOLE
) {
1408 ASSERT(whence
== SEEK_DATA
);
1416 * If at this point we have found the hole we wanted, the returned
1417 * offset may be bigger than the file size as it may be aligned to
1418 * page boundary for unwritten extents. We need to deal with this
1419 * situation in particular.
1421 if (whence
== SEEK_HOLE
)
1422 offset
= min_t(loff_t
, offset
, isize
);
1423 offset
= vfs_setpos(file
, offset
, inode
->i_sb
->s_maxbytes
);
1426 xfs_iunlock(ip
, lock
);
1443 return generic_file_llseek(file
, offset
, whence
);
1446 return xfs_seek_hole_data(file
, offset
, whence
);
1453 * Locking for serialisation of IO during page faults. This results in a lock
1457 * i_mmap_lock (XFS - truncate serialisation)
1459 * i_lock (XFS - extent map serialisation)
1463 struct vm_area_struct
*vma
,
1464 struct vm_fault
*vmf
)
1466 struct xfs_inode
*ip
= XFS_I(vma
->vm_file
->f_mapping
->host
);
1469 trace_xfs_filemap_fault(ip
);
1471 xfs_ilock(ip
, XFS_MMAPLOCK_SHARED
);
1472 error
= filemap_fault(vma
, vmf
);
1473 xfs_iunlock(ip
, XFS_MMAPLOCK_SHARED
);
1479 * mmap()d file has taken write protection fault and is being made writable. We
1480 * can set the page state up correctly for a writable page, which means we can
1481 * do correct delalloc accounting (ENOSPC checking!) and unwritten extent
1485 xfs_filemap_page_mkwrite(
1486 struct vm_area_struct
*vma
,
1487 struct vm_fault
*vmf
)
1489 struct xfs_inode
*ip
= XFS_I(vma
->vm_file
->f_mapping
->host
);
1492 trace_xfs_filemap_page_mkwrite(ip
);
1494 xfs_ilock(ip
, XFS_MMAPLOCK_SHARED
);
1495 error
= block_page_mkwrite(vma
, vmf
, xfs_get_blocks
);
1496 xfs_iunlock(ip
, XFS_MMAPLOCK_SHARED
);
1501 const struct file_operations xfs_file_operations
= {
1502 .llseek
= xfs_file_llseek
,
1503 .read_iter
= xfs_file_read_iter
,
1504 .write_iter
= xfs_file_write_iter
,
1505 .splice_read
= xfs_file_splice_read
,
1506 .splice_write
= iter_file_splice_write
,
1507 .unlocked_ioctl
= xfs_file_ioctl
,
1508 #ifdef CONFIG_COMPAT
1509 .compat_ioctl
= xfs_file_compat_ioctl
,
1511 .mmap
= xfs_file_mmap
,
1512 .open
= xfs_file_open
,
1513 .release
= xfs_file_release
,
1514 .fsync
= xfs_file_fsync
,
1515 .fallocate
= xfs_file_fallocate
,
1518 const struct file_operations xfs_dir_file_operations
= {
1519 .open
= xfs_dir_open
,
1520 .read
= generic_read_dir
,
1521 .iterate
= xfs_file_readdir
,
1522 .llseek
= generic_file_llseek
,
1523 .unlocked_ioctl
= xfs_file_ioctl
,
1524 #ifdef CONFIG_COMPAT
1525 .compat_ioctl
= xfs_file_compat_ioctl
,
1527 .fsync
= xfs_dir_fsync
,
1530 static const struct vm_operations_struct xfs_file_vm_ops
= {
1531 .fault
= xfs_filemap_fault
,
1532 .map_pages
= filemap_map_pages
,
1533 .page_mkwrite
= xfs_filemap_page_mkwrite
,