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 "xfs_iomap.h"
42 #include <linux/dcache.h>
43 #include <linux/falloc.h>
44 #include <linux/pagevec.h>
45 #include <linux/backing-dev.h>
47 static const struct vm_operations_struct xfs_file_vm_ops;
50 * Locking primitives for read and write IO paths to ensure we consistently use
51 * and order the inode->i_mutex, ip->i_lock and ip->i_iolock.
58 if (type & XFS_IOLOCK_EXCL)
59 inode_lock(VFS_I(ip));
68 xfs_iunlock(ip, type);
69 if (type & XFS_IOLOCK_EXCL)
70 inode_unlock(VFS_I(ip));
78 xfs_ilock_demote(ip, type);
79 if (type & XFS_IOLOCK_EXCL)
80 inode_unlock(VFS_I(ip));
84 * Clear the specified ranges to zero through either the pagecache or DAX.
85 * Holes and unwritten extents will be left as-is as they already are zeroed.
94 return iomap_zero_range(VFS_I(ip), pos, count, NULL, &xfs_iomap_ops);
98 xfs_update_prealloc_flags(
100 enum xfs_prealloc_flags flags)
102 struct xfs_trans *tp;
105 error = xfs_trans_alloc(ip->i_mount, &M_RES(ip->i_mount)->tr_writeid,
110 xfs_ilock(ip, XFS_ILOCK_EXCL);
111 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
113 if (!(flags & XFS_PREALLOC_INVISIBLE)) {
114 VFS_I(ip)->i_mode &= ~S_ISUID;
115 if (VFS_I(ip)->i_mode & S_IXGRP)
116 VFS_I(ip)->i_mode &= ~S_ISGID;
117 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
120 if (flags & XFS_PREALLOC_SET)
121 ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
122 if (flags & XFS_PREALLOC_CLEAR)
123 ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC;
125 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
126 if (flags & XFS_PREALLOC_SYNC)
127 xfs_trans_set_sync(tp);
128 return xfs_trans_commit(tp);
132 * Fsync operations on directories are much simpler than on regular files,
133 * as there is no file data to flush, and thus also no need for explicit
134 * cache flush operations, and there are no non-transaction metadata updates
135 * on directories either.
144 struct xfs_inode *ip = XFS_I(file->f_mapping->host);
145 struct xfs_mount *mp = ip->i_mount;
148 trace_xfs_dir_fsync(ip);
150 xfs_ilock(ip, XFS_ILOCK_SHARED);
151 if (xfs_ipincount(ip))
152 lsn = ip->i_itemp->ili_last_lsn;
153 xfs_iunlock(ip, XFS_ILOCK_SHARED);
157 return _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, NULL);
167 struct inode *inode = file->f_mapping->host;
168 struct xfs_inode *ip = XFS_I(inode);
169 struct xfs_mount *mp = ip->i_mount;
174 trace_xfs_file_fsync(ip);
176 error = filemap_write_and_wait_range(inode->i_mapping, start, end);
180 if (XFS_FORCED_SHUTDOWN(mp))
183 xfs_iflags_clear(ip, XFS_ITRUNCATED);
185 if (mp->m_flags & XFS_MOUNT_BARRIER) {
187 * If we have an RT and/or log subvolume we need to make sure
188 * to flush the write cache the device used for file data
189 * first. This is to ensure newly written file data make
190 * it to disk before logging the new inode size in case of
191 * an extending write.
193 if (XFS_IS_REALTIME_INODE(ip))
194 xfs_blkdev_issue_flush(mp->m_rtdev_targp);
195 else if (mp->m_logdev_targp != mp->m_ddev_targp)
196 xfs_blkdev_issue_flush(mp->m_ddev_targp);
200 * All metadata updates are logged, which means that we just have to
201 * flush the log up to the latest LSN that touched the inode. If we have
202 * concurrent fsync/fdatasync() calls, we need them to all block on the
203 * log force before we clear the ili_fsync_fields field. This ensures
204 * that we don't get a racing sync operation that does not wait for the
205 * metadata to hit the journal before returning. If we race with
206 * clearing the ili_fsync_fields, then all that will happen is the log
207 * force will do nothing as the lsn will already be on disk. We can't
208 * race with setting ili_fsync_fields because that is done under
209 * XFS_ILOCK_EXCL, and that can't happen because we hold the lock shared
210 * until after the ili_fsync_fields is cleared.
212 xfs_ilock(ip, XFS_ILOCK_SHARED);
213 if (xfs_ipincount(ip)) {
215 (ip->i_itemp->ili_fsync_fields & ~XFS_ILOG_TIMESTAMP))
216 lsn = ip->i_itemp->ili_last_lsn;
220 error = _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, &log_flushed);
221 ip->i_itemp->ili_fsync_fields = 0;
223 xfs_iunlock(ip, XFS_ILOCK_SHARED);
226 * If we only have a single device, and the log force about was
227 * a no-op we might have to flush the data device cache here.
228 * This can only happen for fdatasync/O_DSYNC if we were overwriting
229 * an already allocated file and thus do not have any metadata to
232 if ((mp->m_flags & XFS_MOUNT_BARRIER) &&
233 mp->m_logdev_targp == mp->m_ddev_targp &&
234 !XFS_IS_REALTIME_INODE(ip) &&
236 xfs_blkdev_issue_flush(mp->m_ddev_targp);
242 xfs_file_dio_aio_read(
246 struct address_space *mapping = iocb->ki_filp->f_mapping;
247 struct inode *inode = mapping->host;
248 struct xfs_inode *ip = XFS_I(inode);
249 loff_t isize = i_size_read(inode);
250 size_t count = iov_iter_count(to);
251 struct iov_iter data;
252 struct xfs_buftarg *target;
255 trace_xfs_file_direct_read(ip, count, iocb->ki_pos);
258 return 0; /* skip atime */
260 if (XFS_IS_REALTIME_INODE(ip))
261 target = ip->i_mount->m_rtdev_targp;
263 target = ip->i_mount->m_ddev_targp;
265 /* DIO must be aligned to device logical sector size */
266 if ((iocb->ki_pos | count) & target->bt_logical_sectormask) {
267 if (iocb->ki_pos == isize)
273 * Locking is a bit tricky here. If we take an exclusive lock for direct
274 * IO, we effectively serialise all new concurrent read IO to this file
275 * and block it behind IO that is currently in progress because IO in
276 * progress holds the IO lock shared. We only need to hold the lock
277 * exclusive to blow away the page cache, so only take lock exclusively
278 * if the page cache needs invalidation. This allows the normal direct
279 * IO case of no page cache pages to proceeed concurrently without
282 xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
283 if (mapping->nrpages) {
284 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
285 xfs_rw_ilock(ip, XFS_IOLOCK_EXCL);
288 * The generic dio code only flushes the range of the particular
289 * I/O. Because we take an exclusive lock here, this whole
290 * sequence is considerably more expensive for us. This has a
291 * noticeable performance impact for any file with cached pages,
292 * even when outside of the range of the particular I/O.
294 * Hence, amortize the cost of the lock against a full file
295 * flush and reduce the chances of repeated iolock cycles going
298 if (mapping->nrpages) {
299 ret = filemap_write_and_wait(mapping);
301 xfs_rw_iunlock(ip, XFS_IOLOCK_EXCL);
306 * Invalidate whole pages. This can return an error if
307 * we fail to invalidate a page, but this should never
308 * happen on XFS. Warn if it does fail.
310 ret = invalidate_inode_pages2(mapping);
314 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
318 ret = __blockdev_direct_IO(iocb, inode, target->bt_bdev, &data,
319 xfs_get_blocks_direct, NULL, NULL, 0);
322 iov_iter_advance(to, ret);
324 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
326 file_accessed(iocb->ki_filp);
330 static noinline ssize_t
335 struct address_space *mapping = iocb->ki_filp->f_mapping;
336 struct inode *inode = mapping->host;
337 struct xfs_inode *ip = XFS_I(inode);
338 struct iov_iter data = *to;
339 size_t count = iov_iter_count(to);
342 trace_xfs_file_dax_read(ip, count, iocb->ki_pos);
345 return 0; /* skip atime */
347 xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
348 ret = dax_do_io(iocb, inode, &data, xfs_get_blocks_direct, NULL, 0);
351 iov_iter_advance(to, ret);
353 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
355 file_accessed(iocb->ki_filp);
360 xfs_file_buffered_aio_read(
364 struct xfs_inode *ip = XFS_I(file_inode(iocb->ki_filp));
367 trace_xfs_file_buffered_read(ip, iov_iter_count(to), iocb->ki_pos);
369 xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
370 ret = generic_file_read_iter(iocb, to);
371 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
381 struct inode *inode = file_inode(iocb->ki_filp);
382 struct xfs_mount *mp = XFS_I(inode)->i_mount;
385 XFS_STATS_INC(mp, xs_read_calls);
387 if (XFS_FORCED_SHUTDOWN(mp))
391 ret = xfs_file_dax_read(iocb, to);
392 else if (iocb->ki_flags & IOCB_DIRECT)
393 ret = xfs_file_dio_aio_read(iocb, to);
395 ret = xfs_file_buffered_aio_read(iocb, to);
398 XFS_STATS_ADD(mp, xs_read_bytes, ret);
403 xfs_file_splice_read(
406 struct pipe_inode_info *pipe,
410 struct xfs_inode *ip = XFS_I(infilp->f_mapping->host);
413 XFS_STATS_INC(ip->i_mount, xs_read_calls);
415 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
418 trace_xfs_file_splice_read(ip, count, *ppos);
421 * DAX inodes cannot ues the page cache for splice, so we have to push
422 * them through the VFS IO path. This means it goes through
423 * ->read_iter, which for us takes the XFS_IOLOCK_SHARED. Hence we
424 * cannot lock the splice operation at this level for DAX inodes.
426 if (IS_DAX(VFS_I(ip))) {
427 ret = default_file_splice_read(infilp, ppos, pipe, count,
432 xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
433 ret = generic_file_splice_read(infilp, ppos, pipe, count, flags);
434 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
437 XFS_STATS_ADD(ip->i_mount, xs_read_bytes, ret);
442 * Zero any on disk space between the current EOF and the new, larger EOF.
444 * This handles the normal case of zeroing the remainder of the last block in
445 * the file and the unusual case of zeroing blocks out beyond the size of the
446 * file. This second case only happens with fixed size extents and when the
447 * system crashes before the inode size was updated but after blocks were
450 * Expects the iolock to be held exclusive, and will take the ilock internally.
452 int /* error (positive) */
454 struct xfs_inode *ip,
455 xfs_off_t offset, /* starting I/O offset */
456 xfs_fsize_t isize, /* current inode size */
459 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
460 ASSERT(offset > isize);
462 trace_xfs_zero_eof(ip, isize, offset - isize);
463 return xfs_zero_range(ip, isize, offset - isize, did_zeroing);
467 * Common pre-write limit and setup checks.
469 * Called with the iolocked held either shared and exclusive according to
470 * @iolock, and returns with it held. Might upgrade the iolock to exclusive
471 * if called for a direct write beyond i_size.
474 xfs_file_aio_write_checks(
476 struct iov_iter *from,
479 struct file *file = iocb->ki_filp;
480 struct inode *inode = file->f_mapping->host;
481 struct xfs_inode *ip = XFS_I(inode);
483 size_t count = iov_iter_count(from);
484 bool drained_dio = false;
487 error = generic_write_checks(iocb, from);
491 error = xfs_break_layouts(inode, iolock, true);
495 /* For changing security info in file_remove_privs() we need i_mutex */
496 if (*iolock == XFS_IOLOCK_SHARED && !IS_NOSEC(inode)) {
497 xfs_rw_iunlock(ip, *iolock);
498 *iolock = XFS_IOLOCK_EXCL;
499 xfs_rw_ilock(ip, *iolock);
503 * If the offset is beyond the size of the file, we need to zero any
504 * blocks that fall between the existing EOF and the start of this
505 * write. If zeroing is needed and we are currently holding the
506 * iolock shared, we need to update it to exclusive which implies
507 * having to redo all checks before.
509 * We need to serialise against EOF updates that occur in IO
510 * completions here. We want to make sure that nobody is changing the
511 * size while we do this check until we have placed an IO barrier (i.e.
512 * hold the XFS_IOLOCK_EXCL) that prevents new IO from being dispatched.
513 * The spinlock effectively forms a memory barrier once we have the
514 * XFS_IOLOCK_EXCL so we are guaranteed to see the latest EOF value
515 * and hence be able to correctly determine if we need to run zeroing.
517 spin_lock(&ip->i_flags_lock);
518 if (iocb->ki_pos > i_size_read(inode)) {
521 spin_unlock(&ip->i_flags_lock);
523 if (*iolock == XFS_IOLOCK_SHARED) {
524 xfs_rw_iunlock(ip, *iolock);
525 *iolock = XFS_IOLOCK_EXCL;
526 xfs_rw_ilock(ip, *iolock);
527 iov_iter_reexpand(from, count);
530 * We now have an IO submission barrier in place, but
531 * AIO can do EOF updates during IO completion and hence
532 * we now need to wait for all of them to drain. Non-AIO
533 * DIO will have drained before we are given the
534 * XFS_IOLOCK_EXCL, and so for most cases this wait is a
537 inode_dio_wait(inode);
541 error = xfs_zero_eof(ip, iocb->ki_pos, i_size_read(inode), &zero);
545 spin_unlock(&ip->i_flags_lock);
548 * Updating the timestamps will grab the ilock again from
549 * xfs_fs_dirty_inode, so we have to call it after dropping the
550 * lock above. Eventually we should look into a way to avoid
551 * the pointless lock roundtrip.
553 if (likely(!(file->f_mode & FMODE_NOCMTIME))) {
554 error = file_update_time(file);
560 * If we're writing the file then make sure to clear the setuid and
561 * setgid bits if the process is not being run by root. This keeps
562 * people from modifying setuid and setgid binaries.
564 if (!IS_NOSEC(inode))
565 return file_remove_privs(file);
570 * xfs_file_dio_aio_write - handle direct IO writes
572 * Lock the inode appropriately to prepare for and issue a direct IO write.
573 * By separating it from the buffered write path we remove all the tricky to
574 * follow locking changes and looping.
576 * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
577 * until we're sure the bytes at the new EOF have been zeroed and/or the cached
578 * pages are flushed out.
580 * In most cases the direct IO writes will be done holding IOLOCK_SHARED
581 * allowing them to be done in parallel with reads and other direct IO writes.
582 * However, if the IO is not aligned to filesystem blocks, the direct IO layer
583 * needs to do sub-block zeroing and that requires serialisation against other
584 * direct IOs to the same block. In this case we need to serialise the
585 * submission of the unaligned IOs so that we don't get racing block zeroing in
586 * the dio layer. To avoid the problem with aio, we also need to wait for
587 * outstanding IOs to complete so that unwritten extent conversion is completed
588 * before we try to map the overlapping block. This is currently implemented by
589 * hitting it with a big hammer (i.e. inode_dio_wait()).
591 * Returns with locks held indicated by @iolock and errors indicated by
592 * negative return values.
595 xfs_file_dio_aio_write(
597 struct iov_iter *from)
599 struct file *file = iocb->ki_filp;
600 struct address_space *mapping = file->f_mapping;
601 struct inode *inode = mapping->host;
602 struct xfs_inode *ip = XFS_I(inode);
603 struct xfs_mount *mp = ip->i_mount;
605 int unaligned_io = 0;
607 size_t count = iov_iter_count(from);
609 struct iov_iter data;
610 struct xfs_buftarg *target = XFS_IS_REALTIME_INODE(ip) ?
611 mp->m_rtdev_targp : mp->m_ddev_targp;
613 /* DIO must be aligned to device logical sector size */
614 if ((iocb->ki_pos | count) & target->bt_logical_sectormask)
617 /* "unaligned" here means not aligned to a filesystem block */
618 if ((iocb->ki_pos & mp->m_blockmask) ||
619 ((iocb->ki_pos + count) & mp->m_blockmask))
623 * We don't need to take an exclusive lock unless there page cache needs
624 * to be invalidated or unaligned IO is being executed. We don't need to
625 * consider the EOF extension case here because
626 * xfs_file_aio_write_checks() will relock the inode as necessary for
627 * EOF zeroing cases and fill out the new inode size as appropriate.
629 if (unaligned_io || mapping->nrpages)
630 iolock = XFS_IOLOCK_EXCL;
632 iolock = XFS_IOLOCK_SHARED;
633 xfs_rw_ilock(ip, iolock);
636 * Recheck if there are cached pages that need invalidate after we got
637 * the iolock to protect against other threads adding new pages while
638 * we were waiting for the iolock.
640 if (mapping->nrpages && iolock == XFS_IOLOCK_SHARED) {
641 xfs_rw_iunlock(ip, iolock);
642 iolock = XFS_IOLOCK_EXCL;
643 xfs_rw_ilock(ip, iolock);
646 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
649 count = iov_iter_count(from);
650 end = iocb->ki_pos + count - 1;
653 * See xfs_file_dio_aio_read() for why we do a full-file flush here.
655 if (mapping->nrpages) {
656 ret = filemap_write_and_wait(VFS_I(ip)->i_mapping);
660 * Invalidate whole pages. This can return an error if we fail
661 * to invalidate a page, but this should never happen on XFS.
662 * Warn if it does fail.
664 ret = invalidate_inode_pages2(VFS_I(ip)->i_mapping);
670 * If we are doing unaligned IO, wait for all other IO to drain,
671 * otherwise demote the lock if we had to flush cached pages
674 inode_dio_wait(inode);
675 else if (iolock == XFS_IOLOCK_EXCL) {
676 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
677 iolock = XFS_IOLOCK_SHARED;
680 trace_xfs_file_direct_write(ip, count, iocb->ki_pos);
683 ret = __blockdev_direct_IO(iocb, inode, target->bt_bdev, &data,
684 xfs_get_blocks_direct, xfs_end_io_direct_write,
685 NULL, DIO_ASYNC_EXTEND);
687 /* see generic_file_direct_write() for why this is necessary */
688 if (mapping->nrpages) {
689 invalidate_inode_pages2_range(mapping,
690 iocb->ki_pos >> PAGE_SHIFT,
696 iov_iter_advance(from, ret);
699 xfs_rw_iunlock(ip, iolock);
702 * No fallback to buffered IO on errors for XFS, direct IO will either
703 * complete fully or fail.
705 ASSERT(ret < 0 || ret == count);
709 static noinline ssize_t
712 struct iov_iter *from)
714 struct address_space *mapping = iocb->ki_filp->f_mapping;
715 struct inode *inode = mapping->host;
716 struct xfs_inode *ip = XFS_I(inode);
717 struct xfs_mount *mp = ip->i_mount;
719 int unaligned_io = 0;
721 struct iov_iter data;
723 /* "unaligned" here means not aligned to a filesystem block */
724 if ((iocb->ki_pos & mp->m_blockmask) ||
725 ((iocb->ki_pos + iov_iter_count(from)) & mp->m_blockmask)) {
727 iolock = XFS_IOLOCK_EXCL;
728 } else if (mapping->nrpages) {
729 iolock = XFS_IOLOCK_EXCL;
731 iolock = XFS_IOLOCK_SHARED;
733 xfs_rw_ilock(ip, iolock);
735 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
740 * Yes, even DAX files can have page cache attached to them: A zeroed
741 * page is inserted into the pagecache when we have to serve a write
742 * fault on a hole. It should never be dirtied and can simply be
743 * dropped from the pagecache once we get real data for the page.
745 * XXX: This is racy against mmap, and there's nothing we can do about
746 * it. dax_do_io() should really do this invalidation internally as
747 * it will know if we've allocated over a holei for this specific IO and
748 * if so it needs to update the mapping tree and invalidate existing
749 * PTEs over the newly allocated range. Remove this invalidation when
750 * dax_do_io() is fixed up.
752 if (mapping->nrpages) {
753 loff_t end = iocb->ki_pos + iov_iter_count(from) - 1;
755 ret = invalidate_inode_pages2_range(mapping,
756 iocb->ki_pos >> PAGE_SHIFT,
761 if (iolock == XFS_IOLOCK_EXCL && !unaligned_io) {
762 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
763 iolock = XFS_IOLOCK_SHARED;
766 trace_xfs_file_dax_write(ip, iov_iter_count(from), iocb->ki_pos);
769 ret = dax_do_io(iocb, inode, &data, xfs_get_blocks_direct,
770 xfs_end_io_direct_write, 0);
773 iov_iter_advance(from, ret);
776 xfs_rw_iunlock(ip, iolock);
781 xfs_file_buffered_aio_write(
783 struct iov_iter *from)
785 struct file *file = iocb->ki_filp;
786 struct address_space *mapping = file->f_mapping;
787 struct inode *inode = mapping->host;
788 struct xfs_inode *ip = XFS_I(inode);
791 int iolock = XFS_IOLOCK_EXCL;
793 xfs_rw_ilock(ip, iolock);
795 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
799 /* We can write back this queue in page reclaim */
800 current->backing_dev_info = inode_to_bdi(inode);
803 trace_xfs_file_buffered_write(ip, iov_iter_count(from), iocb->ki_pos);
804 ret = iomap_file_buffered_write(iocb, from, &xfs_iomap_ops);
805 if (likely(ret >= 0))
809 * If we hit a space limit, try to free up some lingering preallocated
810 * space before returning an error. In the case of ENOSPC, first try to
811 * write back all dirty inodes to free up some of the excess reserved
812 * metadata space. This reduces the chances that the eofblocks scan
813 * waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
814 * also behaves as a filter to prevent too many eofblocks scans from
815 * running at the same time.
817 if (ret == -EDQUOT && !enospc) {
818 enospc = xfs_inode_free_quota_eofblocks(ip);
821 } else if (ret == -ENOSPC && !enospc) {
822 struct xfs_eofblocks eofb = {0};
825 xfs_flush_inodes(ip->i_mount);
826 eofb.eof_scan_owner = ip->i_ino; /* for locking */
827 eofb.eof_flags = XFS_EOF_FLAGS_SYNC;
828 xfs_icache_free_eofblocks(ip->i_mount, &eofb);
832 current->backing_dev_info = NULL;
834 xfs_rw_iunlock(ip, iolock);
841 struct iov_iter *from)
843 struct file *file = iocb->ki_filp;
844 struct address_space *mapping = file->f_mapping;
845 struct inode *inode = mapping->host;
846 struct xfs_inode *ip = XFS_I(inode);
848 size_t ocount = iov_iter_count(from);
850 XFS_STATS_INC(ip->i_mount, xs_write_calls);
855 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
859 ret = xfs_file_dax_write(iocb, from);
860 else if (iocb->ki_flags & IOCB_DIRECT)
861 ret = xfs_file_dio_aio_write(iocb, from);
863 ret = xfs_file_buffered_aio_write(iocb, from);
866 XFS_STATS_ADD(ip->i_mount, xs_write_bytes, ret);
868 /* Handle various SYNC-type writes */
869 ret = generic_write_sync(iocb, ret);
874 #define XFS_FALLOC_FL_SUPPORTED \
875 (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
876 FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
877 FALLOC_FL_INSERT_RANGE)
886 struct inode *inode = file_inode(file);
887 struct xfs_inode *ip = XFS_I(inode);
889 enum xfs_prealloc_flags flags = 0;
890 uint iolock = XFS_IOLOCK_EXCL;
892 bool do_file_insert = 0;
894 if (!S_ISREG(inode->i_mode))
896 if (mode & ~XFS_FALLOC_FL_SUPPORTED)
899 xfs_ilock(ip, iolock);
900 error = xfs_break_layouts(inode, &iolock, false);
904 xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
905 iolock |= XFS_MMAPLOCK_EXCL;
907 if (mode & FALLOC_FL_PUNCH_HOLE) {
908 error = xfs_free_file_space(ip, offset, len);
911 } else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
912 unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
914 if (offset & blksize_mask || len & blksize_mask) {
920 * There is no need to overlap collapse range with EOF,
921 * in which case it is effectively a truncate operation
923 if (offset + len >= i_size_read(inode)) {
928 new_size = i_size_read(inode) - len;
930 error = xfs_collapse_file_space(ip, offset, len);
933 } else if (mode & FALLOC_FL_INSERT_RANGE) {
934 unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
936 new_size = i_size_read(inode) + len;
937 if (offset & blksize_mask || len & blksize_mask) {
942 /* check the new inode size does not wrap through zero */
943 if (new_size > inode->i_sb->s_maxbytes) {
948 /* Offset should be less than i_size */
949 if (offset >= i_size_read(inode)) {
955 flags |= XFS_PREALLOC_SET;
957 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
958 offset + len > i_size_read(inode)) {
959 new_size = offset + len;
960 error = inode_newsize_ok(inode, new_size);
965 if (mode & FALLOC_FL_ZERO_RANGE)
966 error = xfs_zero_file_space(ip, offset, len);
968 error = xfs_alloc_file_space(ip, offset, len,
974 if (file->f_flags & O_DSYNC)
975 flags |= XFS_PREALLOC_SYNC;
977 error = xfs_update_prealloc_flags(ip, flags);
981 /* Change file size if needed */
985 iattr.ia_valid = ATTR_SIZE;
986 iattr.ia_size = new_size;
987 error = xfs_setattr_size(ip, &iattr);
993 * Perform hole insertion now that the file size has been
994 * updated so that if we crash during the operation we don't
995 * leave shifted extents past EOF and hence losing access to
996 * the data that is contained within them.
999 error = xfs_insert_file_space(ip, offset, len);
1002 xfs_iunlock(ip, iolock);
1009 struct inode *inode,
1012 if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
1014 if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
1021 struct inode *inode,
1024 struct xfs_inode *ip = XFS_I(inode);
1028 error = xfs_file_open(inode, file);
1033 * If there are any blocks, read-ahead block 0 as we're almost
1034 * certain to have the next operation be a read there.
1036 mode = xfs_ilock_data_map_shared(ip);
1037 if (ip->i_d.di_nextents > 0)
1038 xfs_dir3_data_readahead(ip, 0, -1);
1039 xfs_iunlock(ip, mode);
1045 struct inode *inode,
1048 return xfs_release(XFS_I(inode));
1054 struct dir_context *ctx)
1056 struct inode *inode = file_inode(file);
1057 xfs_inode_t *ip = XFS_I(inode);
1061 * The Linux API doesn't pass down the total size of the buffer
1062 * we read into down to the filesystem. With the filldir concept
1063 * it's not needed for correct information, but the XFS dir2 leaf
1064 * code wants an estimate of the buffer size to calculate it's
1065 * readahead window and size the buffers used for mapping to
1068 * Try to give it an estimate that's good enough, maybe at some
1069 * point we can change the ->readdir prototype to include the
1070 * buffer size. For now we use the current glibc buffer size.
1072 bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size);
1074 return xfs_readdir(ip, ctx, bufsize);
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_SHIFT;
1166 endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
1167 end = endoff >> PAGE_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);
1296 * caller must lock inode with xfs_ilock_data_map_shared,
1297 * can we craft an appropriate ASSERT?
1299 * end is because the VFS-level lseek interface is defined such that any
1300 * offset past i_size shall return -ENXIO, but we use this for quota code
1301 * which does not maintain i_size, and we want to SEEK_DATA past i_size.
1304 __xfs_seek_hole_data(
1305 struct inode *inode,
1310 struct xfs_inode *ip = XFS_I(inode);
1311 struct xfs_mount *mp = ip->i_mount;
1312 loff_t uninitialized_var(offset);
1313 xfs_fileoff_t fsbno;
1314 xfs_filblks_t lastbno;
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 lastbno = XFS_B_TO_FSB(mp, end);
1330 struct xfs_bmbt_irec map[2];
1334 error = xfs_bmapi_read(ip, fsbno, lastbno - 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);
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, end);
1436 struct inode *inode = file->f_mapping->host;
1437 struct xfs_inode *ip = XFS_I(inode);
1438 struct xfs_mount *mp = ip->i_mount;
1443 if (XFS_FORCED_SHUTDOWN(mp))
1446 lock = xfs_ilock_data_map_shared(ip);
1448 end = i_size_read(inode);
1449 offset = __xfs_seek_hole_data(inode, start, end, whence);
1455 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1458 xfs_iunlock(ip, lock);
1475 return generic_file_llseek(file, offset, whence);
1478 return xfs_seek_hole_data(file, offset, whence);
1485 * Locking for serialisation of IO during page faults. This results in a lock
1489 * sb_start_pagefault(vfs, freeze)
1490 * i_mmaplock (XFS - truncate serialisation)
1492 * i_lock (XFS - extent map serialisation)
1496 * mmap()d file has taken write protection fault and is being made writable. We
1497 * can set the page state up correctly for a writable page, which means we can
1498 * do correct delalloc accounting (ENOSPC checking!) and unwritten extent
1502 xfs_filemap_page_mkwrite(
1503 struct vm_area_struct *vma,
1504 struct vm_fault *vmf)
1506 struct inode *inode = file_inode(vma->vm_file);
1509 trace_xfs_filemap_page_mkwrite(XFS_I(inode));
1511 sb_start_pagefault(inode->i_sb);
1512 file_update_time(vma->vm_file);
1513 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1515 if (IS_DAX(inode)) {
1516 ret = dax_mkwrite(vma, vmf, xfs_get_blocks_dax_fault);
1518 ret = iomap_page_mkwrite(vma, vmf, &xfs_iomap_ops);
1519 ret = block_page_mkwrite_return(ret);
1522 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1523 sb_end_pagefault(inode->i_sb);
1530 struct vm_area_struct *vma,
1531 struct vm_fault *vmf)
1533 struct inode *inode = file_inode(vma->vm_file);
1536 trace_xfs_filemap_fault(XFS_I(inode));
1538 /* DAX can shortcut the normal fault path on write faults! */
1539 if ((vmf->flags & FAULT_FLAG_WRITE) && IS_DAX(inode))
1540 return xfs_filemap_page_mkwrite(vma, vmf);
1542 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1543 if (IS_DAX(inode)) {
1545 * we do not want to trigger unwritten extent conversion on read
1546 * faults - that is unnecessary overhead and would also require
1547 * changes to xfs_get_blocks_direct() to map unwritten extent
1548 * ioend for conversion on read-only mappings.
1550 ret = dax_fault(vma, vmf, xfs_get_blocks_dax_fault);
1552 ret = filemap_fault(vma, vmf);
1553 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1559 * Similar to xfs_filemap_fault(), the DAX fault path can call into here on
1560 * both read and write faults. Hence we need to handle both cases. There is no
1561 * ->pmd_mkwrite callout for huge pages, so we have a single function here to
1562 * handle both cases here. @flags carries the information on the type of fault
1566 xfs_filemap_pmd_fault(
1567 struct vm_area_struct *vma,
1572 struct inode *inode = file_inode(vma->vm_file);
1573 struct xfs_inode *ip = XFS_I(inode);
1577 return VM_FAULT_FALLBACK;
1579 trace_xfs_filemap_pmd_fault(ip);
1581 if (flags & FAULT_FLAG_WRITE) {
1582 sb_start_pagefault(inode->i_sb);
1583 file_update_time(vma->vm_file);
1586 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1587 ret = dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_dax_fault);
1588 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1590 if (flags & FAULT_FLAG_WRITE)
1591 sb_end_pagefault(inode->i_sb);
1597 * pfn_mkwrite was originally inteneded to ensure we capture time stamp
1598 * updates on write faults. In reality, it's need to serialise against
1599 * truncate similar to page_mkwrite. Hence we cycle the XFS_MMAPLOCK_SHARED
1600 * to ensure we serialise the fault barrier in place.
1603 xfs_filemap_pfn_mkwrite(
1604 struct vm_area_struct *vma,
1605 struct vm_fault *vmf)
1608 struct inode *inode = file_inode(vma->vm_file);
1609 struct xfs_inode *ip = XFS_I(inode);
1610 int ret = VM_FAULT_NOPAGE;
1613 trace_xfs_filemap_pfn_mkwrite(ip);
1615 sb_start_pagefault(inode->i_sb);
1616 file_update_time(vma->vm_file);
1618 /* check if the faulting page hasn't raced with truncate */
1619 xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
1620 size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
1621 if (vmf->pgoff >= size)
1622 ret = VM_FAULT_SIGBUS;
1623 else if (IS_DAX(inode))
1624 ret = dax_pfn_mkwrite(vma, vmf);
1625 xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
1626 sb_end_pagefault(inode->i_sb);
1631 static const struct vm_operations_struct xfs_file_vm_ops = {
1632 .fault = xfs_filemap_fault,
1633 .pmd_fault = xfs_filemap_pmd_fault,
1634 .map_pages = filemap_map_pages,
1635 .page_mkwrite = xfs_filemap_page_mkwrite,
1636 .pfn_mkwrite = xfs_filemap_pfn_mkwrite,
1642 struct vm_area_struct *vma)
1644 file_accessed(filp);
1645 vma->vm_ops = &xfs_file_vm_ops;
1646 if (IS_DAX(file_inode(filp)))
1647 vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
1651 const struct file_operations xfs_file_operations = {
1652 .llseek = xfs_file_llseek,
1653 .read_iter = xfs_file_read_iter,
1654 .write_iter = xfs_file_write_iter,
1655 .splice_read = xfs_file_splice_read,
1656 .splice_write = iter_file_splice_write,
1657 .unlocked_ioctl = xfs_file_ioctl,
1658 #ifdef CONFIG_COMPAT
1659 .compat_ioctl = xfs_file_compat_ioctl,
1661 .mmap = xfs_file_mmap,
1662 .open = xfs_file_open,
1663 .release = xfs_file_release,
1664 .fsync = xfs_file_fsync,
1665 .fallocate = xfs_file_fallocate,
1668 const struct file_operations xfs_dir_file_operations = {
1669 .open = xfs_dir_open,
1670 .read = generic_read_dir,
1671 .iterate_shared = xfs_file_readdir,
1672 .llseek = generic_file_llseek,
1673 .unlocked_ioctl = xfs_file_ioctl,
1674 #ifdef CONFIG_COMPAT
1675 .compat_ioctl = xfs_file_compat_ioctl,
1677 .fsync = xfs_dir_fsync,