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"
40 #include <linux/aio.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(file
->f_flags
& O_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
,
401 struct xfs_mount
*mp
= ip
->i_mount
;
402 xfs_fileoff_t last_fsb
= XFS_B_TO_FSBT(mp
, isize
);
403 int zero_offset
= XFS_B_FSB_OFFSET(mp
, isize
);
407 struct xfs_bmbt_irec imap
;
409 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
410 error
= xfs_bmapi_read(ip
, last_fsb
, 1, &imap
, &nimaps
, 0);
411 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
418 * If the block underlying isize is just a hole, then there
419 * is nothing to zero.
421 if (imap
.br_startblock
== HOLESTARTBLOCK
)
424 zero_len
= mp
->m_sb
.sb_blocksize
- zero_offset
;
425 if (isize
+ zero_len
> offset
)
426 zero_len
= offset
- isize
;
427 return xfs_iozero(ip
, isize
, zero_len
);
431 * Zero any on disk space between the current EOF and the new, larger EOF.
433 * This handles the normal case of zeroing the remainder of the last block in
434 * the file and the unusual case of zeroing blocks out beyond the size of the
435 * file. This second case only happens with fixed size extents and when the
436 * system crashes before the inode size was updated but after blocks were
439 * Expects the iolock to be held exclusive, and will take the ilock internally.
441 int /* error (positive) */
443 struct xfs_inode
*ip
,
444 xfs_off_t offset
, /* starting I/O offset */
445 xfs_fsize_t isize
) /* current inode size */
447 struct xfs_mount
*mp
= ip
->i_mount
;
448 xfs_fileoff_t start_zero_fsb
;
449 xfs_fileoff_t end_zero_fsb
;
450 xfs_fileoff_t zero_count_fsb
;
451 xfs_fileoff_t last_fsb
;
452 xfs_fileoff_t zero_off
;
453 xfs_fsize_t zero_len
;
456 struct xfs_bmbt_irec imap
;
458 ASSERT(xfs_isilocked(ip
, XFS_IOLOCK_EXCL
));
459 ASSERT(offset
> isize
);
462 * First handle zeroing the block on which isize resides.
464 * We only zero a part of that block so it is handled specially.
466 if (XFS_B_FSB_OFFSET(mp
, isize
) != 0) {
467 error
= xfs_zero_last_block(ip
, offset
, isize
);
473 * Calculate the range between the new size and the old where blocks
474 * needing to be zeroed may exist.
476 * To get the block where the last byte in the file currently resides,
477 * we need to subtract one from the size and truncate back to a block
478 * boundary. We subtract 1 in case the size is exactly on a block
481 last_fsb
= isize
? XFS_B_TO_FSBT(mp
, isize
- 1) : (xfs_fileoff_t
)-1;
482 start_zero_fsb
= XFS_B_TO_FSB(mp
, (xfs_ufsize_t
)isize
);
483 end_zero_fsb
= XFS_B_TO_FSBT(mp
, offset
- 1);
484 ASSERT((xfs_sfiloff_t
)last_fsb
< (xfs_sfiloff_t
)start_zero_fsb
);
485 if (last_fsb
== end_zero_fsb
) {
487 * The size was only incremented on its last block.
488 * We took care of that above, so just return.
493 ASSERT(start_zero_fsb
<= end_zero_fsb
);
494 while (start_zero_fsb
<= end_zero_fsb
) {
496 zero_count_fsb
= end_zero_fsb
- start_zero_fsb
+ 1;
498 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
499 error
= xfs_bmapi_read(ip
, start_zero_fsb
, zero_count_fsb
,
501 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
507 if (imap
.br_state
== XFS_EXT_UNWRITTEN
||
508 imap
.br_startblock
== HOLESTARTBLOCK
) {
509 start_zero_fsb
= imap
.br_startoff
+ imap
.br_blockcount
;
510 ASSERT(start_zero_fsb
<= (end_zero_fsb
+ 1));
515 * There are blocks we need to zero.
517 zero_off
= XFS_FSB_TO_B(mp
, start_zero_fsb
);
518 zero_len
= XFS_FSB_TO_B(mp
, imap
.br_blockcount
);
520 if ((zero_off
+ zero_len
) > offset
)
521 zero_len
= offset
- zero_off
;
523 error
= xfs_iozero(ip
, zero_off
, zero_len
);
527 start_zero_fsb
= imap
.br_startoff
+ imap
.br_blockcount
;
528 ASSERT(start_zero_fsb
<= (end_zero_fsb
+ 1));
535 * Common pre-write limit and setup checks.
537 * Called with the iolocked held either shared and exclusive according to
538 * @iolock, and returns with it held. Might upgrade the iolock to exclusive
539 * if called for a direct write beyond i_size.
542 xfs_file_aio_write_checks(
548 struct inode
*inode
= file
->f_mapping
->host
;
549 struct xfs_inode
*ip
= XFS_I(inode
);
553 error
= generic_write_checks(file
, pos
, count
, S_ISBLK(inode
->i_mode
));
558 * If the offset is beyond the size of the file, we need to zero any
559 * blocks that fall between the existing EOF and the start of this
560 * write. If zeroing is needed and we are currently holding the
561 * iolock shared, we need to update it to exclusive which implies
562 * having to redo all checks before.
564 if (*pos
> i_size_read(inode
)) {
565 if (*iolock
== XFS_IOLOCK_SHARED
) {
566 xfs_rw_iunlock(ip
, *iolock
);
567 *iolock
= XFS_IOLOCK_EXCL
;
568 xfs_rw_ilock(ip
, *iolock
);
571 error
= xfs_zero_eof(ip
, *pos
, i_size_read(inode
));
577 * Updating the timestamps will grab the ilock again from
578 * xfs_fs_dirty_inode, so we have to call it after dropping the
579 * lock above. Eventually we should look into a way to avoid
580 * the pointless lock roundtrip.
582 if (likely(!(file
->f_mode
& FMODE_NOCMTIME
))) {
583 error
= file_update_time(file
);
589 * If we're writing the file then make sure to clear the setuid and
590 * setgid bits if the process is not being run by root. This keeps
591 * people from modifying setuid and setgid binaries.
593 return file_remove_suid(file
);
597 * xfs_file_dio_aio_write - handle direct IO writes
599 * Lock the inode appropriately to prepare for and issue a direct IO write.
600 * By separating it from the buffered write path we remove all the tricky to
601 * follow locking changes and looping.
603 * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
604 * until we're sure the bytes at the new EOF have been zeroed and/or the cached
605 * pages are flushed out.
607 * In most cases the direct IO writes will be done holding IOLOCK_SHARED
608 * allowing them to be done in parallel with reads and other direct IO writes.
609 * However, if the IO is not aligned to filesystem blocks, the direct IO layer
610 * needs to do sub-block zeroing and that requires serialisation against other
611 * direct IOs to the same block. In this case we need to serialise the
612 * submission of the unaligned IOs so that we don't get racing block zeroing in
613 * the dio layer. To avoid the problem with aio, we also need to wait for
614 * outstanding IOs to complete so that unwritten extent conversion is completed
615 * before we try to map the overlapping block. This is currently implemented by
616 * hitting it with a big hammer (i.e. inode_dio_wait()).
618 * Returns with locks held indicated by @iolock and errors indicated by
619 * negative return values.
622 xfs_file_dio_aio_write(
624 struct iov_iter
*from
)
626 struct file
*file
= iocb
->ki_filp
;
627 struct address_space
*mapping
= file
->f_mapping
;
628 struct inode
*inode
= mapping
->host
;
629 struct xfs_inode
*ip
= XFS_I(inode
);
630 struct xfs_mount
*mp
= ip
->i_mount
;
632 int unaligned_io
= 0;
634 size_t count
= iov_iter_count(from
);
635 loff_t pos
= iocb
->ki_pos
;
636 struct xfs_buftarg
*target
= XFS_IS_REALTIME_INODE(ip
) ?
637 mp
->m_rtdev_targp
: mp
->m_ddev_targp
;
639 /* DIO must be aligned to device logical sector size */
640 if ((pos
| count
) & target
->bt_logical_sectormask
)
643 /* "unaligned" here means not aligned to a filesystem block */
644 if ((pos
& mp
->m_blockmask
) || ((pos
+ count
) & mp
->m_blockmask
))
648 * We don't need to take an exclusive lock unless there page cache needs
649 * to be invalidated or unaligned IO is being executed. We don't need to
650 * consider the EOF extension case here because
651 * xfs_file_aio_write_checks() will relock the inode as necessary for
652 * EOF zeroing cases and fill out the new inode size as appropriate.
654 if (unaligned_io
|| mapping
->nrpages
)
655 iolock
= XFS_IOLOCK_EXCL
;
657 iolock
= XFS_IOLOCK_SHARED
;
658 xfs_rw_ilock(ip
, iolock
);
661 * Recheck if there are cached pages that need invalidate after we got
662 * the iolock to protect against other threads adding new pages while
663 * we were waiting for the iolock.
665 if (mapping
->nrpages
&& iolock
== XFS_IOLOCK_SHARED
) {
666 xfs_rw_iunlock(ip
, iolock
);
667 iolock
= XFS_IOLOCK_EXCL
;
668 xfs_rw_ilock(ip
, iolock
);
671 ret
= xfs_file_aio_write_checks(file
, &pos
, &count
, &iolock
);
674 iov_iter_truncate(from
, count
);
676 if (mapping
->nrpages
) {
677 ret
= filemap_write_and_wait_range(VFS_I(ip
)->i_mapping
,
678 pos
, pos
+ count
- 1);
682 * Invalidate whole pages. This can return an error if
683 * we fail to invalidate a page, but this should never
684 * happen on XFS. Warn if it does fail.
686 ret
= invalidate_inode_pages2_range(VFS_I(ip
)->i_mapping
,
687 pos
>> PAGE_CACHE_SHIFT
,
688 (pos
+ count
- 1) >> PAGE_CACHE_SHIFT
);
694 * If we are doing unaligned IO, wait for all other IO to drain,
695 * otherwise demote the lock if we had to flush cached pages
698 inode_dio_wait(inode
);
699 else if (iolock
== XFS_IOLOCK_EXCL
) {
700 xfs_rw_ilock_demote(ip
, XFS_IOLOCK_EXCL
);
701 iolock
= XFS_IOLOCK_SHARED
;
704 trace_xfs_file_direct_write(ip
, count
, iocb
->ki_pos
, 0);
705 ret
= generic_file_direct_write(iocb
, from
, pos
);
708 xfs_rw_iunlock(ip
, iolock
);
710 /* No fallback to buffered IO on errors for XFS. */
711 ASSERT(ret
< 0 || ret
== count
);
716 xfs_file_buffered_aio_write(
718 struct iov_iter
*from
)
720 struct file
*file
= iocb
->ki_filp
;
721 struct address_space
*mapping
= file
->f_mapping
;
722 struct inode
*inode
= mapping
->host
;
723 struct xfs_inode
*ip
= XFS_I(inode
);
726 int iolock
= XFS_IOLOCK_EXCL
;
727 loff_t pos
= iocb
->ki_pos
;
728 size_t count
= iov_iter_count(from
);
730 xfs_rw_ilock(ip
, iolock
);
732 ret
= xfs_file_aio_write_checks(file
, &pos
, &count
, &iolock
);
736 iov_iter_truncate(from
, count
);
737 /* We can write back this queue in page reclaim */
738 current
->backing_dev_info
= inode_to_bdi(inode
);
741 trace_xfs_file_buffered_write(ip
, count
, iocb
->ki_pos
, 0);
742 ret
= generic_perform_write(file
, from
, pos
);
743 if (likely(ret
>= 0))
744 iocb
->ki_pos
= pos
+ ret
;
747 * If we hit a space limit, try to free up some lingering preallocated
748 * space before returning an error. In the case of ENOSPC, first try to
749 * write back all dirty inodes to free up some of the excess reserved
750 * metadata space. This reduces the chances that the eofblocks scan
751 * waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
752 * also behaves as a filter to prevent too many eofblocks scans from
753 * running at the same time.
755 if (ret
== -EDQUOT
&& !enospc
) {
756 enospc
= xfs_inode_free_quota_eofblocks(ip
);
759 } else if (ret
== -ENOSPC
&& !enospc
) {
760 struct xfs_eofblocks eofb
= {0};
763 xfs_flush_inodes(ip
->i_mount
);
764 eofb
.eof_scan_owner
= ip
->i_ino
; /* for locking */
765 eofb
.eof_flags
= XFS_EOF_FLAGS_SYNC
;
766 xfs_icache_free_eofblocks(ip
->i_mount
, &eofb
);
770 current
->backing_dev_info
= NULL
;
772 xfs_rw_iunlock(ip
, iolock
);
779 struct iov_iter
*from
)
781 struct file
*file
= iocb
->ki_filp
;
782 struct address_space
*mapping
= file
->f_mapping
;
783 struct inode
*inode
= mapping
->host
;
784 struct xfs_inode
*ip
= XFS_I(inode
);
786 size_t ocount
= iov_iter_count(from
);
788 XFS_STATS_INC(xs_write_calls
);
793 if (XFS_FORCED_SHUTDOWN(ip
->i_mount
))
796 if (unlikely(file
->f_flags
& O_DIRECT
))
797 ret
= xfs_file_dio_aio_write(iocb
, from
);
799 ret
= xfs_file_buffered_aio_write(iocb
, from
);
804 XFS_STATS_ADD(xs_write_bytes
, ret
);
806 /* Handle various SYNC-type writes */
807 err
= generic_write_sync(file
, iocb
->ki_pos
- ret
, ret
);
821 struct inode
*inode
= file_inode(file
);
822 struct xfs_inode
*ip
= XFS_I(inode
);
824 enum xfs_prealloc_flags flags
= 0;
827 if (!S_ISREG(inode
->i_mode
))
829 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
|
830 FALLOC_FL_COLLAPSE_RANGE
| FALLOC_FL_ZERO_RANGE
))
833 xfs_ilock(ip
, XFS_IOLOCK_EXCL
);
834 if (mode
& FALLOC_FL_PUNCH_HOLE
) {
835 error
= xfs_free_file_space(ip
, offset
, len
);
838 } else if (mode
& FALLOC_FL_COLLAPSE_RANGE
) {
839 unsigned blksize_mask
= (1 << inode
->i_blkbits
) - 1;
841 if (offset
& blksize_mask
|| len
& blksize_mask
) {
847 * There is no need to overlap collapse range with EOF,
848 * in which case it is effectively a truncate operation
850 if (offset
+ len
>= i_size_read(inode
)) {
855 new_size
= i_size_read(inode
) - len
;
857 error
= xfs_collapse_file_space(ip
, offset
, len
);
861 flags
|= XFS_PREALLOC_SET
;
863 if (!(mode
& FALLOC_FL_KEEP_SIZE
) &&
864 offset
+ len
> i_size_read(inode
)) {
865 new_size
= offset
+ len
;
866 error
= inode_newsize_ok(inode
, new_size
);
871 if (mode
& FALLOC_FL_ZERO_RANGE
)
872 error
= xfs_zero_file_space(ip
, offset
, len
);
874 error
= xfs_alloc_file_space(ip
, offset
, len
,
880 if (file
->f_flags
& O_DSYNC
)
881 flags
|= XFS_PREALLOC_SYNC
;
883 error
= xfs_update_prealloc_flags(ip
, flags
);
887 /* Change file size if needed */
891 iattr
.ia_valid
= ATTR_SIZE
;
892 iattr
.ia_size
= new_size
;
893 error
= xfs_setattr_size(ip
, &iattr
);
897 xfs_iunlock(ip
, XFS_IOLOCK_EXCL
);
907 if (!(file
->f_flags
& O_LARGEFILE
) && i_size_read(inode
) > MAX_NON_LFS
)
909 if (XFS_FORCED_SHUTDOWN(XFS_M(inode
->i_sb
)))
919 struct xfs_inode
*ip
= XFS_I(inode
);
923 error
= xfs_file_open(inode
, file
);
928 * If there are any blocks, read-ahead block 0 as we're almost
929 * certain to have the next operation be a read there.
931 mode
= xfs_ilock_data_map_shared(ip
);
932 if (ip
->i_d
.di_nextents
> 0)
933 xfs_dir3_data_readahead(ip
, 0, -1);
934 xfs_iunlock(ip
, mode
);
943 return xfs_release(XFS_I(inode
));
949 struct dir_context
*ctx
)
951 struct inode
*inode
= file_inode(file
);
952 xfs_inode_t
*ip
= XFS_I(inode
);
956 * The Linux API doesn't pass down the total size of the buffer
957 * we read into down to the filesystem. With the filldir concept
958 * it's not needed for correct information, but the XFS dir2 leaf
959 * code wants an estimate of the buffer size to calculate it's
960 * readahead window and size the buffers used for mapping to
963 * Try to give it an estimate that's good enough, maybe at some
964 * point we can change the ->readdir prototype to include the
965 * buffer size. For now we use the current glibc buffer size.
967 bufsize
= (size_t)min_t(loff_t
, 32768, ip
->i_d
.di_size
);
969 return xfs_readdir(ip
, ctx
, bufsize
);
975 struct vm_area_struct
*vma
)
977 vma
->vm_ops
= &xfs_file_vm_ops
;
984 * mmap()d file has taken write protection fault and is being made
985 * writable. We can set the page state up correctly for a writable
986 * page, which means we can do correct delalloc accounting (ENOSPC
987 * checking!) and unwritten extent mapping.
991 struct vm_area_struct
*vma
,
992 struct vm_fault
*vmf
)
994 return block_page_mkwrite(vma
, vmf
, xfs_get_blocks
);
998 * This type is designed to indicate the type of offset we would like
999 * to search from page cache for xfs_seek_hole_data().
1007 * Lookup the desired type of offset from the given page.
1009 * On success, return true and the offset argument will point to the
1010 * start of the region that was found. Otherwise this function will
1011 * return false and keep the offset argument unchanged.
1014 xfs_lookup_buffer_offset(
1019 loff_t lastoff
= page_offset(page
);
1021 struct buffer_head
*bh
, *head
;
1023 bh
= head
= page_buffers(page
);
1026 * Unwritten extents that have data in the page
1027 * cache covering them can be identified by the
1028 * BH_Unwritten state flag. Pages with multiple
1029 * buffers might have a mix of holes, data and
1030 * unwritten extents - any buffer with valid
1031 * data in it should have BH_Uptodate flag set
1034 if (buffer_unwritten(bh
) ||
1035 buffer_uptodate(bh
)) {
1036 if (type
== DATA_OFF
)
1039 if (type
== HOLE_OFF
)
1047 lastoff
+= bh
->b_size
;
1048 } while ((bh
= bh
->b_this_page
) != head
);
1054 * This routine is called to find out and return a data or hole offset
1055 * from the page cache for unwritten extents according to the desired
1056 * type for xfs_seek_hole_data().
1058 * The argument offset is used to tell where we start to search from the
1059 * page cache. Map is used to figure out the end points of the range to
1062 * Return true if the desired type of offset was found, and the argument
1063 * offset is filled with that address. Otherwise, return false and keep
1067 xfs_find_get_desired_pgoff(
1068 struct inode
*inode
,
1069 struct xfs_bmbt_irec
*map
,
1073 struct xfs_inode
*ip
= XFS_I(inode
);
1074 struct xfs_mount
*mp
= ip
->i_mount
;
1075 struct pagevec pvec
;
1079 loff_t startoff
= *offset
;
1080 loff_t lastoff
= startoff
;
1083 pagevec_init(&pvec
, 0);
1085 index
= startoff
>> PAGE_CACHE_SHIFT
;
1086 endoff
= XFS_FSB_TO_B(mp
, map
->br_startoff
+ map
->br_blockcount
);
1087 end
= endoff
>> PAGE_CACHE_SHIFT
;
1093 want
= min_t(pgoff_t
, end
- index
, PAGEVEC_SIZE
);
1094 nr_pages
= pagevec_lookup(&pvec
, inode
->i_mapping
, index
,
1097 * No page mapped into given range. If we are searching holes
1098 * and if this is the first time we got into the loop, it means
1099 * that the given offset is landed in a hole, return it.
1101 * If we have already stepped through some block buffers to find
1102 * holes but they all contains data. In this case, the last
1103 * offset is already updated and pointed to the end of the last
1104 * mapped page, if it does not reach the endpoint to search,
1105 * that means there should be a hole between them.
1107 if (nr_pages
== 0) {
1108 /* Data search found nothing */
1109 if (type
== DATA_OFF
)
1112 ASSERT(type
== HOLE_OFF
);
1113 if (lastoff
== startoff
|| lastoff
< endoff
) {
1121 * At lease we found one page. If this is the first time we
1122 * step into the loop, and if the first page index offset is
1123 * greater than the given search offset, a hole was found.
1125 if (type
== HOLE_OFF
&& lastoff
== startoff
&&
1126 lastoff
< page_offset(pvec
.pages
[0])) {
1131 for (i
= 0; i
< nr_pages
; i
++) {
1132 struct page
*page
= pvec
.pages
[i
];
1136 * At this point, the page may be truncated or
1137 * invalidated (changing page->mapping to NULL),
1138 * or even swizzled back from swapper_space to tmpfs
1139 * file mapping. However, page->index will not change
1140 * because we have a reference on the page.
1142 * Searching done if the page index is out of range.
1143 * If the current offset is not reaches the end of
1144 * the specified search range, there should be a hole
1147 if (page
->index
> end
) {
1148 if (type
== HOLE_OFF
&& lastoff
< endoff
) {
1157 * Page truncated or invalidated(page->mapping == NULL).
1158 * We can freely skip it and proceed to check the next
1161 if (unlikely(page
->mapping
!= inode
->i_mapping
)) {
1166 if (!page_has_buffers(page
)) {
1171 found
= xfs_lookup_buffer_offset(page
, &b_offset
, type
);
1174 * The found offset may be less than the start
1175 * point to search if this is the first time to
1178 *offset
= max_t(loff_t
, startoff
, b_offset
);
1184 * We either searching data but nothing was found, or
1185 * searching hole but found a data buffer. In either
1186 * case, probably the next page contains the desired
1187 * things, update the last offset to it so.
1189 lastoff
= page_offset(page
) + PAGE_SIZE
;
1194 * The number of returned pages less than our desired, search
1195 * done. In this case, nothing was found for searching data,
1196 * but we found a hole behind the last offset.
1198 if (nr_pages
< want
) {
1199 if (type
== HOLE_OFF
) {
1206 index
= pvec
.pages
[i
- 1]->index
+ 1;
1207 pagevec_release(&pvec
);
1208 } while (index
<= end
);
1211 pagevec_release(&pvec
);
1221 struct inode
*inode
= file
->f_mapping
->host
;
1222 struct xfs_inode
*ip
= XFS_I(inode
);
1223 struct xfs_mount
*mp
= ip
->i_mount
;
1224 loff_t
uninitialized_var(offset
);
1226 xfs_fileoff_t fsbno
;
1231 if (XFS_FORCED_SHUTDOWN(mp
))
1234 lock
= xfs_ilock_data_map_shared(ip
);
1236 isize
= i_size_read(inode
);
1237 if (start
>= isize
) {
1243 * Try to read extents from the first block indicated
1244 * by fsbno to the end block of the file.
1246 fsbno
= XFS_B_TO_FSBT(mp
, start
);
1247 end
= XFS_B_TO_FSB(mp
, isize
);
1250 struct xfs_bmbt_irec map
[2];
1254 error
= xfs_bmapi_read(ip
, fsbno
, end
- fsbno
, map
, &nmap
,
1259 /* No extents at given offset, must be beyond EOF */
1265 for (i
= 0; i
< nmap
; i
++) {
1266 offset
= max_t(loff_t
, start
,
1267 XFS_FSB_TO_B(mp
, map
[i
].br_startoff
));
1269 /* Landed in the hole we wanted? */
1270 if (whence
== SEEK_HOLE
&&
1271 map
[i
].br_startblock
== HOLESTARTBLOCK
)
1274 /* Landed in the data extent we wanted? */
1275 if (whence
== SEEK_DATA
&&
1276 (map
[i
].br_startblock
== DELAYSTARTBLOCK
||
1277 (map
[i
].br_state
== XFS_EXT_NORM
&&
1278 !isnullstartblock(map
[i
].br_startblock
))))
1282 * Landed in an unwritten extent, try to search
1283 * for hole or data from page cache.
1285 if (map
[i
].br_state
== XFS_EXT_UNWRITTEN
) {
1286 if (xfs_find_get_desired_pgoff(inode
, &map
[i
],
1287 whence
== SEEK_HOLE
? HOLE_OFF
: DATA_OFF
,
1294 * We only received one extent out of the two requested. This
1295 * means we've hit EOF and didn't find what we are looking for.
1299 * If we were looking for a hole, set offset to
1300 * the end of the file (i.e., there is an implicit
1301 * hole at the end of any file).
1303 if (whence
== SEEK_HOLE
) {
1308 * If we were looking for data, it's nowhere to be found
1310 ASSERT(whence
== SEEK_DATA
);
1318 * Nothing was found, proceed to the next round of search
1319 * if the next reading offset is not at or beyond EOF.
1321 fsbno
= map
[i
- 1].br_startoff
+ map
[i
- 1].br_blockcount
;
1322 start
= XFS_FSB_TO_B(mp
, fsbno
);
1323 if (start
>= isize
) {
1324 if (whence
== SEEK_HOLE
) {
1328 ASSERT(whence
== SEEK_DATA
);
1336 * If at this point we have found the hole we wanted, the returned
1337 * offset may be bigger than the file size as it may be aligned to
1338 * page boundary for unwritten extents. We need to deal with this
1339 * situation in particular.
1341 if (whence
== SEEK_HOLE
)
1342 offset
= min_t(loff_t
, offset
, isize
);
1343 offset
= vfs_setpos(file
, offset
, inode
->i_sb
->s_maxbytes
);
1346 xfs_iunlock(ip
, lock
);
1363 return generic_file_llseek(file
, offset
, whence
);
1366 return xfs_seek_hole_data(file
, offset
, whence
);
1372 const struct file_operations xfs_file_operations
= {
1373 .llseek
= xfs_file_llseek
,
1374 .read
= new_sync_read
,
1375 .write
= new_sync_write
,
1376 .read_iter
= xfs_file_read_iter
,
1377 .write_iter
= xfs_file_write_iter
,
1378 .splice_read
= xfs_file_splice_read
,
1379 .splice_write
= iter_file_splice_write
,
1380 .unlocked_ioctl
= xfs_file_ioctl
,
1381 #ifdef CONFIG_COMPAT
1382 .compat_ioctl
= xfs_file_compat_ioctl
,
1384 .mmap
= xfs_file_mmap
,
1385 .open
= xfs_file_open
,
1386 .release
= xfs_file_release
,
1387 .fsync
= xfs_file_fsync
,
1388 .fallocate
= xfs_file_fallocate
,
1391 const struct file_operations xfs_dir_file_operations
= {
1392 .open
= xfs_dir_open
,
1393 .read
= generic_read_dir
,
1394 .iterate
= xfs_file_readdir
,
1395 .llseek
= generic_file_llseek
,
1396 .unlocked_ioctl
= xfs_file_ioctl
,
1397 #ifdef CONFIG_COMPAT
1398 .compat_ioctl
= xfs_file_compat_ioctl
,
1400 .fsync
= xfs_dir_fsync
,
1403 static const struct vm_operations_struct xfs_file_vm_ops
= {
1404 .fault
= filemap_fault
,
1405 .map_pages
= filemap_map_pages
,
1406 .page_mkwrite
= xfs_vm_page_mkwrite
,