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/aio.h>
42 #include <linux/dcache.h>
43 #include <linux/falloc.h>
44 #include <linux/pagevec.h>
46 static const struct vm_operations_struct xfs_file_vm_ops
;
49 * Locking primitives for read and write IO paths to ensure we consistently use
50 * and order the inode->i_mutex, ip->i_lock and ip->i_iolock.
57 if (type
& XFS_IOLOCK_EXCL
)
58 mutex_lock(&VFS_I(ip
)->i_mutex
);
67 xfs_iunlock(ip
, type
);
68 if (type
& XFS_IOLOCK_EXCL
)
69 mutex_unlock(&VFS_I(ip
)->i_mutex
);
77 xfs_ilock_demote(ip
, type
);
78 if (type
& XFS_IOLOCK_EXCL
)
79 mutex_unlock(&VFS_I(ip
)->i_mutex
);
85 * xfs_iozero clears the specified range of buffer supplied,
86 * and marks all the affected blocks as valid and modified. If
87 * an affected block is not allocated, it will be allocated. If
88 * an affected block is not completely overwritten, and is not
89 * valid before the operation, it will be read from disk before
90 * being partially zeroed.
94 struct xfs_inode
*ip
, /* inode */
95 loff_t pos
, /* offset in file */
96 size_t count
) /* size of data to zero */
99 struct address_space
*mapping
;
102 mapping
= VFS_I(ip
)->i_mapping
;
104 unsigned offset
, bytes
;
107 offset
= (pos
& (PAGE_CACHE_SIZE
-1)); /* Within page */
108 bytes
= PAGE_CACHE_SIZE
- offset
;
112 status
= pagecache_write_begin(NULL
, mapping
, pos
, bytes
,
113 AOP_FLAG_UNINTERRUPTIBLE
,
118 zero_user(page
, offset
, bytes
);
120 status
= pagecache_write_end(NULL
, mapping
, pos
, bytes
, bytes
,
122 WARN_ON(status
<= 0); /* can't return less than zero! */
132 xfs_update_prealloc_flags(
133 struct xfs_inode
*ip
,
134 enum xfs_prealloc_flags flags
)
136 struct xfs_trans
*tp
;
139 tp
= xfs_trans_alloc(ip
->i_mount
, XFS_TRANS_WRITEID
);
140 error
= xfs_trans_reserve(tp
, &M_RES(ip
->i_mount
)->tr_writeid
, 0, 0);
142 xfs_trans_cancel(tp
, 0);
146 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
147 xfs_trans_ijoin(tp
, ip
, XFS_ILOCK_EXCL
);
149 if (!(flags
& XFS_PREALLOC_INVISIBLE
)) {
150 ip
->i_d
.di_mode
&= ~S_ISUID
;
151 if (ip
->i_d
.di_mode
& S_IXGRP
)
152 ip
->i_d
.di_mode
&= ~S_ISGID
;
153 xfs_trans_ichgtime(tp
, ip
, XFS_ICHGTIME_MOD
| XFS_ICHGTIME_CHG
);
156 if (flags
& XFS_PREALLOC_SET
)
157 ip
->i_d
.di_flags
|= XFS_DIFLAG_PREALLOC
;
158 if (flags
& XFS_PREALLOC_CLEAR
)
159 ip
->i_d
.di_flags
&= ~XFS_DIFLAG_PREALLOC
;
161 xfs_trans_log_inode(tp
, ip
, XFS_ILOG_CORE
);
162 if (flags
& XFS_PREALLOC_SYNC
)
163 xfs_trans_set_sync(tp
);
164 return xfs_trans_commit(tp
, 0);
168 * Fsync operations on directories are much simpler than on regular files,
169 * as there is no file data to flush, and thus also no need for explicit
170 * cache flush operations, and there are no non-transaction metadata updates
171 * on directories either.
180 struct xfs_inode
*ip
= XFS_I(file
->f_mapping
->host
);
181 struct xfs_mount
*mp
= ip
->i_mount
;
184 trace_xfs_dir_fsync(ip
);
186 xfs_ilock(ip
, XFS_ILOCK_SHARED
);
187 if (xfs_ipincount(ip
))
188 lsn
= ip
->i_itemp
->ili_last_lsn
;
189 xfs_iunlock(ip
, XFS_ILOCK_SHARED
);
193 return _xfs_log_force_lsn(mp
, lsn
, XFS_LOG_SYNC
, NULL
);
203 struct inode
*inode
= file
->f_mapping
->host
;
204 struct xfs_inode
*ip
= XFS_I(inode
);
205 struct xfs_mount
*mp
= ip
->i_mount
;
210 trace_xfs_file_fsync(ip
);
212 error
= filemap_write_and_wait_range(inode
->i_mapping
, start
, end
);
216 if (XFS_FORCED_SHUTDOWN(mp
))
219 xfs_iflags_clear(ip
, XFS_ITRUNCATED
);
221 if (mp
->m_flags
& XFS_MOUNT_BARRIER
) {
223 * If we have an RT and/or log subvolume we need to make sure
224 * to flush the write cache the device used for file data
225 * first. This is to ensure newly written file data make
226 * it to disk before logging the new inode size in case of
227 * an extending write.
229 if (XFS_IS_REALTIME_INODE(ip
))
230 xfs_blkdev_issue_flush(mp
->m_rtdev_targp
);
231 else if (mp
->m_logdev_targp
!= mp
->m_ddev_targp
)
232 xfs_blkdev_issue_flush(mp
->m_ddev_targp
);
236 * All metadata updates are logged, which means that we just have
237 * to flush the log up to the latest LSN that touched the inode.
239 xfs_ilock(ip
, XFS_ILOCK_SHARED
);
240 if (xfs_ipincount(ip
)) {
242 (ip
->i_itemp
->ili_fields
& ~XFS_ILOG_TIMESTAMP
))
243 lsn
= ip
->i_itemp
->ili_last_lsn
;
245 xfs_iunlock(ip
, XFS_ILOCK_SHARED
);
248 error
= _xfs_log_force_lsn(mp
, lsn
, XFS_LOG_SYNC
, &log_flushed
);
251 * If we only have a single device, and the log force about was
252 * a no-op we might have to flush the data device cache here.
253 * This can only happen for fdatasync/O_DSYNC if we were overwriting
254 * an already allocated file and thus do not have any metadata to
257 if ((mp
->m_flags
& XFS_MOUNT_BARRIER
) &&
258 mp
->m_logdev_targp
== mp
->m_ddev_targp
&&
259 !XFS_IS_REALTIME_INODE(ip
) &&
261 xfs_blkdev_issue_flush(mp
->m_ddev_targp
);
271 struct file
*file
= iocb
->ki_filp
;
272 struct inode
*inode
= file
->f_mapping
->host
;
273 struct xfs_inode
*ip
= XFS_I(inode
);
274 struct xfs_mount
*mp
= ip
->i_mount
;
275 size_t size
= iov_iter_count(to
);
279 loff_t pos
= iocb
->ki_pos
;
281 XFS_STATS_INC(xs_read_calls
);
283 if (unlikely(file
->f_flags
& O_DIRECT
))
284 ioflags
|= XFS_IO_ISDIRECT
;
285 if (file
->f_mode
& FMODE_NOCMTIME
)
286 ioflags
|= XFS_IO_INVIS
;
288 if (unlikely(ioflags
& XFS_IO_ISDIRECT
)) {
289 xfs_buftarg_t
*target
=
290 XFS_IS_REALTIME_INODE(ip
) ?
291 mp
->m_rtdev_targp
: mp
->m_ddev_targp
;
292 /* DIO must be aligned to device logical sector size */
293 if ((pos
| size
) & target
->bt_logical_sectormask
) {
294 if (pos
== i_size_read(inode
))
300 n
= mp
->m_super
->s_maxbytes
- pos
;
301 if (n
<= 0 || size
== 0)
307 if (XFS_FORCED_SHUTDOWN(mp
))
311 * Locking is a bit tricky here. If we take an exclusive lock
312 * for direct IO, we effectively serialise all new concurrent
313 * read IO to this file and block it behind IO that is currently in
314 * progress because IO in progress holds the IO lock shared. We only
315 * need to hold the lock exclusive to blow away the page cache, so
316 * only take lock exclusively if the page cache needs invalidation.
317 * This allows the normal direct IO case of no page cache pages to
318 * proceeed concurrently without serialisation.
320 xfs_rw_ilock(ip
, XFS_IOLOCK_SHARED
);
321 if ((ioflags
& XFS_IO_ISDIRECT
) && inode
->i_mapping
->nrpages
) {
322 xfs_rw_iunlock(ip
, XFS_IOLOCK_SHARED
);
323 xfs_rw_ilock(ip
, XFS_IOLOCK_EXCL
);
325 if (inode
->i_mapping
->nrpages
) {
326 ret
= filemap_write_and_wait_range(
327 VFS_I(ip
)->i_mapping
,
328 pos
, pos
+ size
- 1);
330 xfs_rw_iunlock(ip
, XFS_IOLOCK_EXCL
);
335 * Invalidate whole pages. This can return an error if
336 * we fail to invalidate a page, but this should never
337 * happen on XFS. Warn if it does fail.
339 ret
= invalidate_inode_pages2_range(VFS_I(ip
)->i_mapping
,
340 pos
>> PAGE_CACHE_SHIFT
,
341 (pos
+ size
- 1) >> PAGE_CACHE_SHIFT
);
345 xfs_rw_ilock_demote(ip
, XFS_IOLOCK_EXCL
);
348 trace_xfs_file_read(ip
, size
, pos
, ioflags
);
350 ret
= generic_file_read_iter(iocb
, to
);
352 XFS_STATS_ADD(xs_read_bytes
, ret
);
354 xfs_rw_iunlock(ip
, XFS_IOLOCK_SHARED
);
359 xfs_file_splice_read(
362 struct pipe_inode_info
*pipe
,
366 struct xfs_inode
*ip
= XFS_I(infilp
->f_mapping
->host
);
370 XFS_STATS_INC(xs_read_calls
);
372 if (infilp
->f_mode
& FMODE_NOCMTIME
)
373 ioflags
|= XFS_IO_INVIS
;
375 if (XFS_FORCED_SHUTDOWN(ip
->i_mount
))
378 xfs_rw_ilock(ip
, XFS_IOLOCK_SHARED
);
380 trace_xfs_file_splice_read(ip
, count
, *ppos
, ioflags
);
382 ret
= generic_file_splice_read(infilp
, ppos
, pipe
, count
, flags
);
384 XFS_STATS_ADD(xs_read_bytes
, ret
);
386 xfs_rw_iunlock(ip
, XFS_IOLOCK_SHARED
);
391 * This routine is called to handle zeroing any space in the last block of the
392 * file that is beyond the EOF. We do this since the size is being increased
393 * without writing anything to that block and we don't want to read the
394 * garbage on the disk.
396 STATIC
int /* error (positive) */
398 struct xfs_inode
*ip
,
403 struct xfs_mount
*mp
= ip
->i_mount
;
404 xfs_fileoff_t last_fsb
= XFS_B_TO_FSBT(mp
, isize
);
405 int zero_offset
= XFS_B_FSB_OFFSET(mp
, isize
);
409 struct xfs_bmbt_irec imap
;
411 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
412 error
= xfs_bmapi_read(ip
, last_fsb
, 1, &imap
, &nimaps
, 0);
413 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
420 * If the block underlying isize is just a hole, then there
421 * is nothing to zero.
423 if (imap
.br_startblock
== HOLESTARTBLOCK
)
426 zero_len
= mp
->m_sb
.sb_blocksize
- zero_offset
;
427 if (isize
+ zero_len
> offset
)
428 zero_len
= offset
- isize
;
430 return xfs_iozero(ip
, isize
, zero_len
);
434 * Zero any on disk space between the current EOF and the new, larger EOF.
436 * This handles the normal case of zeroing the remainder of the last block in
437 * the file and the unusual case of zeroing blocks out beyond the size of the
438 * file. This second case only happens with fixed size extents and when the
439 * system crashes before the inode size was updated but after blocks were
442 * Expects the iolock to be held exclusive, and will take the ilock internally.
444 int /* error (positive) */
446 struct xfs_inode
*ip
,
447 xfs_off_t offset
, /* starting I/O offset */
448 xfs_fsize_t isize
, /* current inode size */
451 struct xfs_mount
*mp
= ip
->i_mount
;
452 xfs_fileoff_t start_zero_fsb
;
453 xfs_fileoff_t end_zero_fsb
;
454 xfs_fileoff_t zero_count_fsb
;
455 xfs_fileoff_t last_fsb
;
456 xfs_fileoff_t zero_off
;
457 xfs_fsize_t zero_len
;
460 struct xfs_bmbt_irec imap
;
462 ASSERT(xfs_isilocked(ip
, XFS_IOLOCK_EXCL
));
463 ASSERT(offset
> isize
);
466 * First handle zeroing the block on which isize resides.
468 * We only zero a part of that block so it is handled specially.
470 if (XFS_B_FSB_OFFSET(mp
, isize
) != 0) {
471 error
= xfs_zero_last_block(ip
, offset
, isize
, did_zeroing
);
477 * Calculate the range between the new size and the old where blocks
478 * needing to be zeroed may exist.
480 * To get the block where the last byte in the file currently resides,
481 * we need to subtract one from the size and truncate back to a block
482 * boundary. We subtract 1 in case the size is exactly on a block
485 last_fsb
= isize
? XFS_B_TO_FSBT(mp
, isize
- 1) : (xfs_fileoff_t
)-1;
486 start_zero_fsb
= XFS_B_TO_FSB(mp
, (xfs_ufsize_t
)isize
);
487 end_zero_fsb
= XFS_B_TO_FSBT(mp
, offset
- 1);
488 ASSERT((xfs_sfiloff_t
)last_fsb
< (xfs_sfiloff_t
)start_zero_fsb
);
489 if (last_fsb
== end_zero_fsb
) {
491 * The size was only incremented on its last block.
492 * We took care of that above, so just return.
497 ASSERT(start_zero_fsb
<= end_zero_fsb
);
498 while (start_zero_fsb
<= end_zero_fsb
) {
500 zero_count_fsb
= end_zero_fsb
- start_zero_fsb
+ 1;
502 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
503 error
= xfs_bmapi_read(ip
, start_zero_fsb
, zero_count_fsb
,
505 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
511 if (imap
.br_state
== XFS_EXT_UNWRITTEN
||
512 imap
.br_startblock
== HOLESTARTBLOCK
) {
513 start_zero_fsb
= imap
.br_startoff
+ imap
.br_blockcount
;
514 ASSERT(start_zero_fsb
<= (end_zero_fsb
+ 1));
519 * There are blocks we need to zero.
521 zero_off
= XFS_FSB_TO_B(mp
, start_zero_fsb
);
522 zero_len
= XFS_FSB_TO_B(mp
, imap
.br_blockcount
);
524 if ((zero_off
+ zero_len
) > offset
)
525 zero_len
= offset
- zero_off
;
527 error
= xfs_iozero(ip
, zero_off
, zero_len
);
532 start_zero_fsb
= imap
.br_startoff
+ imap
.br_blockcount
;
533 ASSERT(start_zero_fsb
<= (end_zero_fsb
+ 1));
540 * Common pre-write limit and setup checks.
542 * Called with the iolocked held either shared and exclusive according to
543 * @iolock, and returns with it held. Might upgrade the iolock to exclusive
544 * if called for a direct write beyond i_size.
547 xfs_file_aio_write_checks(
553 struct inode
*inode
= file
->f_mapping
->host
;
554 struct xfs_inode
*ip
= XFS_I(inode
);
558 error
= generic_write_checks(file
, pos
, count
, S_ISBLK(inode
->i_mode
));
562 error
= xfs_break_layouts(inode
, iolock
);
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 if (*pos
> i_size_read(inode
)) {
576 if (*iolock
== XFS_IOLOCK_SHARED
) {
577 xfs_rw_iunlock(ip
, *iolock
);
578 *iolock
= XFS_IOLOCK_EXCL
;
579 xfs_rw_ilock(ip
, *iolock
);
582 error
= xfs_zero_eof(ip
, *pos
, i_size_read(inode
), &zero
);
588 * Updating the timestamps will grab the ilock again from
589 * xfs_fs_dirty_inode, so we have to call it after dropping the
590 * lock above. Eventually we should look into a way to avoid
591 * the pointless lock roundtrip.
593 if (likely(!(file
->f_mode
& FMODE_NOCMTIME
))) {
594 error
= file_update_time(file
);
600 * If we're writing the file then make sure to clear the setuid and
601 * setgid bits if the process is not being run by root. This keeps
602 * people from modifying setuid and setgid binaries.
604 return file_remove_suid(file
);
608 * xfs_file_dio_aio_write - handle direct IO writes
610 * Lock the inode appropriately to prepare for and issue a direct IO write.
611 * By separating it from the buffered write path we remove all the tricky to
612 * follow locking changes and looping.
614 * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
615 * until we're sure the bytes at the new EOF have been zeroed and/or the cached
616 * pages are flushed out.
618 * In most cases the direct IO writes will be done holding IOLOCK_SHARED
619 * allowing them to be done in parallel with reads and other direct IO writes.
620 * However, if the IO is not aligned to filesystem blocks, the direct IO layer
621 * needs to do sub-block zeroing and that requires serialisation against other
622 * direct IOs to the same block. In this case we need to serialise the
623 * submission of the unaligned IOs so that we don't get racing block zeroing in
624 * the dio layer. To avoid the problem with aio, we also need to wait for
625 * outstanding IOs to complete so that unwritten extent conversion is completed
626 * before we try to map the overlapping block. This is currently implemented by
627 * hitting it with a big hammer (i.e. inode_dio_wait()).
629 * Returns with locks held indicated by @iolock and errors indicated by
630 * negative return values.
633 xfs_file_dio_aio_write(
635 struct iov_iter
*from
)
637 struct file
*file
= iocb
->ki_filp
;
638 struct address_space
*mapping
= file
->f_mapping
;
639 struct inode
*inode
= mapping
->host
;
640 struct xfs_inode
*ip
= XFS_I(inode
);
641 struct xfs_mount
*mp
= ip
->i_mount
;
643 int unaligned_io
= 0;
645 size_t count
= iov_iter_count(from
);
646 loff_t pos
= iocb
->ki_pos
;
647 struct xfs_buftarg
*target
= XFS_IS_REALTIME_INODE(ip
) ?
648 mp
->m_rtdev_targp
: mp
->m_ddev_targp
;
650 /* DIO must be aligned to device logical sector size */
651 if ((pos
| count
) & target
->bt_logical_sectormask
)
654 /* "unaligned" here means not aligned to a filesystem block */
655 if ((pos
& mp
->m_blockmask
) || ((pos
+ count
) & mp
->m_blockmask
))
659 * We don't need to take an exclusive lock unless there page cache needs
660 * to be invalidated or unaligned IO is being executed. We don't need to
661 * consider the EOF extension case here because
662 * xfs_file_aio_write_checks() will relock the inode as necessary for
663 * EOF zeroing cases and fill out the new inode size as appropriate.
665 if (unaligned_io
|| mapping
->nrpages
)
666 iolock
= XFS_IOLOCK_EXCL
;
668 iolock
= XFS_IOLOCK_SHARED
;
669 xfs_rw_ilock(ip
, iolock
);
672 * Recheck if there are cached pages that need invalidate after we got
673 * the iolock to protect against other threads adding new pages while
674 * we were waiting for the iolock.
676 if (mapping
->nrpages
&& iolock
== XFS_IOLOCK_SHARED
) {
677 xfs_rw_iunlock(ip
, iolock
);
678 iolock
= XFS_IOLOCK_EXCL
;
679 xfs_rw_ilock(ip
, iolock
);
682 ret
= xfs_file_aio_write_checks(file
, &pos
, &count
, &iolock
);
685 iov_iter_truncate(from
, count
);
687 if (mapping
->nrpages
) {
688 ret
= filemap_write_and_wait_range(VFS_I(ip
)->i_mapping
,
689 pos
, pos
+ count
- 1);
693 * Invalidate whole pages. This can return an error if
694 * we fail to invalidate a page, but this should never
695 * happen on XFS. Warn if it does fail.
697 ret
= invalidate_inode_pages2_range(VFS_I(ip
)->i_mapping
,
698 pos
>> PAGE_CACHE_SHIFT
,
699 (pos
+ count
- 1) >> PAGE_CACHE_SHIFT
);
705 * If we are doing unaligned IO, wait for all other IO to drain,
706 * otherwise demote the lock if we had to flush cached pages
709 inode_dio_wait(inode
);
710 else if (iolock
== XFS_IOLOCK_EXCL
) {
711 xfs_rw_ilock_demote(ip
, XFS_IOLOCK_EXCL
);
712 iolock
= XFS_IOLOCK_SHARED
;
715 trace_xfs_file_direct_write(ip
, count
, iocb
->ki_pos
, 0);
716 ret
= generic_file_direct_write(iocb
, from
, pos
);
719 xfs_rw_iunlock(ip
, iolock
);
721 /* No fallback to buffered IO on errors for XFS. */
722 ASSERT(ret
< 0 || ret
== count
);
727 xfs_file_buffered_aio_write(
729 struct iov_iter
*from
)
731 struct file
*file
= iocb
->ki_filp
;
732 struct address_space
*mapping
= file
->f_mapping
;
733 struct inode
*inode
= mapping
->host
;
734 struct xfs_inode
*ip
= XFS_I(inode
);
737 int iolock
= XFS_IOLOCK_EXCL
;
738 loff_t pos
= iocb
->ki_pos
;
739 size_t count
= iov_iter_count(from
);
741 xfs_rw_ilock(ip
, iolock
);
743 ret
= xfs_file_aio_write_checks(file
, &pos
, &count
, &iolock
);
747 iov_iter_truncate(from
, count
);
748 /* We can write back this queue in page reclaim */
749 current
->backing_dev_info
= inode_to_bdi(inode
);
752 trace_xfs_file_buffered_write(ip
, count
, iocb
->ki_pos
, 0);
753 ret
= generic_perform_write(file
, from
, pos
);
754 if (likely(ret
>= 0))
755 iocb
->ki_pos
= pos
+ ret
;
758 * If we hit a space limit, try to free up some lingering preallocated
759 * space before returning an error. In the case of ENOSPC, first try to
760 * write back all dirty inodes to free up some of the excess reserved
761 * metadata space. This reduces the chances that the eofblocks scan
762 * waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
763 * also behaves as a filter to prevent too many eofblocks scans from
764 * running at the same time.
766 if (ret
== -EDQUOT
&& !enospc
) {
767 enospc
= xfs_inode_free_quota_eofblocks(ip
);
770 } else if (ret
== -ENOSPC
&& !enospc
) {
771 struct xfs_eofblocks eofb
= {0};
774 xfs_flush_inodes(ip
->i_mount
);
775 eofb
.eof_scan_owner
= ip
->i_ino
; /* for locking */
776 eofb
.eof_flags
= XFS_EOF_FLAGS_SYNC
;
777 xfs_icache_free_eofblocks(ip
->i_mount
, &eofb
);
781 current
->backing_dev_info
= NULL
;
783 xfs_rw_iunlock(ip
, iolock
);
790 struct iov_iter
*from
)
792 struct file
*file
= iocb
->ki_filp
;
793 struct address_space
*mapping
= file
->f_mapping
;
794 struct inode
*inode
= mapping
->host
;
795 struct xfs_inode
*ip
= XFS_I(inode
);
797 size_t ocount
= iov_iter_count(from
);
799 XFS_STATS_INC(xs_write_calls
);
804 if (XFS_FORCED_SHUTDOWN(ip
->i_mount
))
807 if (unlikely(file
->f_flags
& O_DIRECT
))
808 ret
= xfs_file_dio_aio_write(iocb
, from
);
810 ret
= xfs_file_buffered_aio_write(iocb
, from
);
815 XFS_STATS_ADD(xs_write_bytes
, ret
);
817 /* Handle various SYNC-type writes */
818 err
= generic_write_sync(file
, iocb
->ki_pos
- ret
, ret
);
832 struct inode
*inode
= file_inode(file
);
833 struct xfs_inode
*ip
= XFS_I(inode
);
835 enum xfs_prealloc_flags flags
= 0;
836 uint iolock
= XFS_IOLOCK_EXCL
;
839 if (!S_ISREG(inode
->i_mode
))
841 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
|
842 FALLOC_FL_COLLAPSE_RANGE
| FALLOC_FL_ZERO_RANGE
))
845 xfs_ilock(ip
, iolock
);
846 error
= xfs_break_layouts(inode
, &iolock
);
850 if (mode
& FALLOC_FL_PUNCH_HOLE
) {
851 error
= xfs_free_file_space(ip
, offset
, len
);
854 } else if (mode
& FALLOC_FL_COLLAPSE_RANGE
) {
855 unsigned blksize_mask
= (1 << inode
->i_blkbits
) - 1;
857 if (offset
& blksize_mask
|| len
& blksize_mask
) {
863 * There is no need to overlap collapse range with EOF,
864 * in which case it is effectively a truncate operation
866 if (offset
+ len
>= i_size_read(inode
)) {
871 new_size
= i_size_read(inode
) - len
;
873 error
= xfs_collapse_file_space(ip
, offset
, len
);
877 flags
|= XFS_PREALLOC_SET
;
879 if (!(mode
& FALLOC_FL_KEEP_SIZE
) &&
880 offset
+ len
> i_size_read(inode
)) {
881 new_size
= offset
+ len
;
882 error
= inode_newsize_ok(inode
, new_size
);
887 if (mode
& FALLOC_FL_ZERO_RANGE
)
888 error
= xfs_zero_file_space(ip
, offset
, len
);
890 error
= xfs_alloc_file_space(ip
, offset
, len
,
896 if (file
->f_flags
& O_DSYNC
)
897 flags
|= XFS_PREALLOC_SYNC
;
899 error
= xfs_update_prealloc_flags(ip
, flags
);
903 /* Change file size if needed */
907 iattr
.ia_valid
= ATTR_SIZE
;
908 iattr
.ia_size
= new_size
;
909 error
= xfs_setattr_size(ip
, &iattr
);
913 xfs_iunlock(ip
, iolock
);
923 if (!(file
->f_flags
& O_LARGEFILE
) && i_size_read(inode
) > MAX_NON_LFS
)
925 if (XFS_FORCED_SHUTDOWN(XFS_M(inode
->i_sb
)))
935 struct xfs_inode
*ip
= XFS_I(inode
);
939 error
= xfs_file_open(inode
, file
);
944 * If there are any blocks, read-ahead block 0 as we're almost
945 * certain to have the next operation be a read there.
947 mode
= xfs_ilock_data_map_shared(ip
);
948 if (ip
->i_d
.di_nextents
> 0)
949 xfs_dir3_data_readahead(ip
, 0, -1);
950 xfs_iunlock(ip
, mode
);
959 return xfs_release(XFS_I(inode
));
965 struct dir_context
*ctx
)
967 struct inode
*inode
= file_inode(file
);
968 xfs_inode_t
*ip
= XFS_I(inode
);
972 * The Linux API doesn't pass down the total size of the buffer
973 * we read into down to the filesystem. With the filldir concept
974 * it's not needed for correct information, but the XFS dir2 leaf
975 * code wants an estimate of the buffer size to calculate it's
976 * readahead window and size the buffers used for mapping to
979 * Try to give it an estimate that's good enough, maybe at some
980 * point we can change the ->readdir prototype to include the
981 * buffer size. For now we use the current glibc buffer size.
983 bufsize
= (size_t)min_t(loff_t
, 32768, ip
->i_d
.di_size
);
985 return xfs_readdir(ip
, ctx
, bufsize
);
991 struct vm_area_struct
*vma
)
993 vma
->vm_ops
= &xfs_file_vm_ops
;
1000 * mmap()d file has taken write protection fault and is being made
1001 * writable. We can set the page state up correctly for a writable
1002 * page, which means we can do correct delalloc accounting (ENOSPC
1003 * checking!) and unwritten extent mapping.
1006 xfs_vm_page_mkwrite(
1007 struct vm_area_struct
*vma
,
1008 struct vm_fault
*vmf
)
1010 return block_page_mkwrite(vma
, vmf
, xfs_get_blocks
);
1014 * This type is designed to indicate the type of offset we would like
1015 * to search from page cache for xfs_seek_hole_data().
1023 * Lookup the desired type of offset from the given page.
1025 * On success, return true and the offset argument will point to the
1026 * start of the region that was found. Otherwise this function will
1027 * return false and keep the offset argument unchanged.
1030 xfs_lookup_buffer_offset(
1035 loff_t lastoff
= page_offset(page
);
1037 struct buffer_head
*bh
, *head
;
1039 bh
= head
= page_buffers(page
);
1042 * Unwritten extents that have data in the page
1043 * cache covering them can be identified by the
1044 * BH_Unwritten state flag. Pages with multiple
1045 * buffers might have a mix of holes, data and
1046 * unwritten extents - any buffer with valid
1047 * data in it should have BH_Uptodate flag set
1050 if (buffer_unwritten(bh
) ||
1051 buffer_uptodate(bh
)) {
1052 if (type
== DATA_OFF
)
1055 if (type
== HOLE_OFF
)
1063 lastoff
+= bh
->b_size
;
1064 } while ((bh
= bh
->b_this_page
) != head
);
1070 * This routine is called to find out and return a data or hole offset
1071 * from the page cache for unwritten extents according to the desired
1072 * type for xfs_seek_hole_data().
1074 * The argument offset is used to tell where we start to search from the
1075 * page cache. Map is used to figure out the end points of the range to
1078 * Return true if the desired type of offset was found, and the argument
1079 * offset is filled with that address. Otherwise, return false and keep
1083 xfs_find_get_desired_pgoff(
1084 struct inode
*inode
,
1085 struct xfs_bmbt_irec
*map
,
1089 struct xfs_inode
*ip
= XFS_I(inode
);
1090 struct xfs_mount
*mp
= ip
->i_mount
;
1091 struct pagevec pvec
;
1095 loff_t startoff
= *offset
;
1096 loff_t lastoff
= startoff
;
1099 pagevec_init(&pvec
, 0);
1101 index
= startoff
>> PAGE_CACHE_SHIFT
;
1102 endoff
= XFS_FSB_TO_B(mp
, map
->br_startoff
+ map
->br_blockcount
);
1103 end
= endoff
>> PAGE_CACHE_SHIFT
;
1109 want
= min_t(pgoff_t
, end
- index
, PAGEVEC_SIZE
);
1110 nr_pages
= pagevec_lookup(&pvec
, inode
->i_mapping
, index
,
1113 * No page mapped into given range. If we are searching holes
1114 * and if this is the first time we got into the loop, it means
1115 * that the given offset is landed in a hole, return it.
1117 * If we have already stepped through some block buffers to find
1118 * holes but they all contains data. In this case, the last
1119 * offset is already updated and pointed to the end of the last
1120 * mapped page, if it does not reach the endpoint to search,
1121 * that means there should be a hole between them.
1123 if (nr_pages
== 0) {
1124 /* Data search found nothing */
1125 if (type
== DATA_OFF
)
1128 ASSERT(type
== HOLE_OFF
);
1129 if (lastoff
== startoff
|| lastoff
< endoff
) {
1137 * At lease we found one page. If this is the first time we
1138 * step into the loop, and if the first page index offset is
1139 * greater than the given search offset, a hole was found.
1141 if (type
== HOLE_OFF
&& lastoff
== startoff
&&
1142 lastoff
< page_offset(pvec
.pages
[0])) {
1147 for (i
= 0; i
< nr_pages
; i
++) {
1148 struct page
*page
= pvec
.pages
[i
];
1152 * At this point, the page may be truncated or
1153 * invalidated (changing page->mapping to NULL),
1154 * or even swizzled back from swapper_space to tmpfs
1155 * file mapping. However, page->index will not change
1156 * because we have a reference on the page.
1158 * Searching done if the page index is out of range.
1159 * If the current offset is not reaches the end of
1160 * the specified search range, there should be a hole
1163 if (page
->index
> end
) {
1164 if (type
== HOLE_OFF
&& lastoff
< endoff
) {
1173 * Page truncated or invalidated(page->mapping == NULL).
1174 * We can freely skip it and proceed to check the next
1177 if (unlikely(page
->mapping
!= inode
->i_mapping
)) {
1182 if (!page_has_buffers(page
)) {
1187 found
= xfs_lookup_buffer_offset(page
, &b_offset
, type
);
1190 * The found offset may be less than the start
1191 * point to search if this is the first time to
1194 *offset
= max_t(loff_t
, startoff
, b_offset
);
1200 * We either searching data but nothing was found, or
1201 * searching hole but found a data buffer. In either
1202 * case, probably the next page contains the desired
1203 * things, update the last offset to it so.
1205 lastoff
= page_offset(page
) + PAGE_SIZE
;
1210 * The number of returned pages less than our desired, search
1211 * done. In this case, nothing was found for searching data,
1212 * but we found a hole behind the last offset.
1214 if (nr_pages
< want
) {
1215 if (type
== HOLE_OFF
) {
1222 index
= pvec
.pages
[i
- 1]->index
+ 1;
1223 pagevec_release(&pvec
);
1224 } while (index
<= end
);
1227 pagevec_release(&pvec
);
1237 struct inode
*inode
= file
->f_mapping
->host
;
1238 struct xfs_inode
*ip
= XFS_I(inode
);
1239 struct xfs_mount
*mp
= ip
->i_mount
;
1240 loff_t
uninitialized_var(offset
);
1242 xfs_fileoff_t fsbno
;
1247 if (XFS_FORCED_SHUTDOWN(mp
))
1250 lock
= xfs_ilock_data_map_shared(ip
);
1252 isize
= i_size_read(inode
);
1253 if (start
>= isize
) {
1259 * Try to read extents from the first block indicated
1260 * by fsbno to the end block of the file.
1262 fsbno
= XFS_B_TO_FSBT(mp
, start
);
1263 end
= XFS_B_TO_FSB(mp
, isize
);
1266 struct xfs_bmbt_irec map
[2];
1270 error
= xfs_bmapi_read(ip
, fsbno
, end
- fsbno
, map
, &nmap
,
1275 /* No extents at given offset, must be beyond EOF */
1281 for (i
= 0; i
< nmap
; i
++) {
1282 offset
= max_t(loff_t
, start
,
1283 XFS_FSB_TO_B(mp
, map
[i
].br_startoff
));
1285 /* Landed in the hole we wanted? */
1286 if (whence
== SEEK_HOLE
&&
1287 map
[i
].br_startblock
== HOLESTARTBLOCK
)
1290 /* Landed in the data extent we wanted? */
1291 if (whence
== SEEK_DATA
&&
1292 (map
[i
].br_startblock
== DELAYSTARTBLOCK
||
1293 (map
[i
].br_state
== XFS_EXT_NORM
&&
1294 !isnullstartblock(map
[i
].br_startblock
))))
1298 * Landed in an unwritten extent, try to search
1299 * for hole or data from page cache.
1301 if (map
[i
].br_state
== XFS_EXT_UNWRITTEN
) {
1302 if (xfs_find_get_desired_pgoff(inode
, &map
[i
],
1303 whence
== SEEK_HOLE
? HOLE_OFF
: DATA_OFF
,
1310 * We only received one extent out of the two requested. This
1311 * means we've hit EOF and didn't find what we are looking for.
1315 * If we were looking for a hole, set offset to
1316 * the end of the file (i.e., there is an implicit
1317 * hole at the end of any file).
1319 if (whence
== SEEK_HOLE
) {
1324 * If we were looking for data, it's nowhere to be found
1326 ASSERT(whence
== SEEK_DATA
);
1334 * Nothing was found, proceed to the next round of search
1335 * if the next reading offset is not at or beyond EOF.
1337 fsbno
= map
[i
- 1].br_startoff
+ map
[i
- 1].br_blockcount
;
1338 start
= XFS_FSB_TO_B(mp
, fsbno
);
1339 if (start
>= isize
) {
1340 if (whence
== SEEK_HOLE
) {
1344 ASSERT(whence
== SEEK_DATA
);
1352 * If at this point we have found the hole we wanted, the returned
1353 * offset may be bigger than the file size as it may be aligned to
1354 * page boundary for unwritten extents. We need to deal with this
1355 * situation in particular.
1357 if (whence
== SEEK_HOLE
)
1358 offset
= min_t(loff_t
, offset
, isize
);
1359 offset
= vfs_setpos(file
, offset
, inode
->i_sb
->s_maxbytes
);
1362 xfs_iunlock(ip
, lock
);
1379 return generic_file_llseek(file
, offset
, whence
);
1382 return xfs_seek_hole_data(file
, offset
, whence
);
1388 const struct file_operations xfs_file_operations
= {
1389 .llseek
= xfs_file_llseek
,
1390 .read
= new_sync_read
,
1391 .write
= new_sync_write
,
1392 .read_iter
= xfs_file_read_iter
,
1393 .write_iter
= xfs_file_write_iter
,
1394 .splice_read
= xfs_file_splice_read
,
1395 .splice_write
= iter_file_splice_write
,
1396 .unlocked_ioctl
= xfs_file_ioctl
,
1397 #ifdef CONFIG_COMPAT
1398 .compat_ioctl
= xfs_file_compat_ioctl
,
1400 .mmap
= xfs_file_mmap
,
1401 .open
= xfs_file_open
,
1402 .release
= xfs_file_release
,
1403 .fsync
= xfs_file_fsync
,
1404 .fallocate
= xfs_file_fallocate
,
1407 const struct file_operations xfs_dir_file_operations
= {
1408 .open
= xfs_dir_open
,
1409 .read
= generic_read_dir
,
1410 .iterate
= xfs_file_readdir
,
1411 .llseek
= generic_file_llseek
,
1412 .unlocked_ioctl
= xfs_file_ioctl
,
1413 #ifdef CONFIG_COMPAT
1414 .compat_ioctl
= xfs_file_compat_ioctl
,
1416 .fsync
= xfs_dir_fsync
,
1419 static const struct vm_operations_struct xfs_file_vm_ops
= {
1420 .fault
= filemap_fault
,
1421 .map_pages
= filemap_map_pages
,
1422 .page_mkwrite
= xfs_vm_page_mkwrite
,