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"
41 #include "xfs_reflink.h"
43 #include <linux/dcache.h>
44 #include <linux/falloc.h>
45 #include <linux/pagevec.h>
46 #include <linux/backing-dev.h>
48 static const struct vm_operations_struct xfs_file_vm_ops;
51 * Clear the specified ranges to zero through either the pagecache or DAX.
52 * Holes and unwritten extents will be left as-is as they already are zeroed.
61 return iomap_zero_range(VFS_I(ip), pos, count, NULL, &xfs_iomap_ops);
65 xfs_update_prealloc_flags(
67 enum xfs_prealloc_flags flags)
72 error = xfs_trans_alloc(ip->i_mount, &M_RES(ip->i_mount)->tr_writeid,
77 xfs_ilock(ip, XFS_ILOCK_EXCL);
78 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
80 if (!(flags & XFS_PREALLOC_INVISIBLE)) {
81 VFS_I(ip)->i_mode &= ~S_ISUID;
82 if (VFS_I(ip)->i_mode & S_IXGRP)
83 VFS_I(ip)->i_mode &= ~S_ISGID;
84 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
87 if (flags & XFS_PREALLOC_SET)
88 ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
89 if (flags & XFS_PREALLOC_CLEAR)
90 ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC;
92 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
93 if (flags & XFS_PREALLOC_SYNC)
94 xfs_trans_set_sync(tp);
95 return xfs_trans_commit(tp);
99 * Fsync operations on directories are much simpler than on regular files,
100 * as there is no file data to flush, and thus also no need for explicit
101 * cache flush operations, and there are no non-transaction metadata updates
102 * on directories either.
111 struct xfs_inode *ip = XFS_I(file->f_mapping->host);
112 struct xfs_mount *mp = ip->i_mount;
115 trace_xfs_dir_fsync(ip);
117 xfs_ilock(ip, XFS_ILOCK_SHARED);
118 if (xfs_ipincount(ip))
119 lsn = ip->i_itemp->ili_last_lsn;
120 xfs_iunlock(ip, XFS_ILOCK_SHARED);
124 return _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, NULL);
134 struct inode *inode = file->f_mapping->host;
135 struct xfs_inode *ip = XFS_I(inode);
136 struct xfs_mount *mp = ip->i_mount;
141 trace_xfs_file_fsync(ip);
143 error = filemap_write_and_wait_range(inode->i_mapping, start, end);
147 if (XFS_FORCED_SHUTDOWN(mp))
150 xfs_iflags_clear(ip, XFS_ITRUNCATED);
153 * If we have an RT and/or log subvolume we need to make sure to flush
154 * the write cache the device used for file data first. This is to
155 * ensure newly written file data make it to disk before logging the new
156 * inode size in case of an extending write.
158 if (XFS_IS_REALTIME_INODE(ip))
159 xfs_blkdev_issue_flush(mp->m_rtdev_targp);
160 else if (mp->m_logdev_targp != mp->m_ddev_targp)
161 xfs_blkdev_issue_flush(mp->m_ddev_targp);
164 * All metadata updates are logged, which means that we just have to
165 * flush the log up to the latest LSN that touched the inode. If we have
166 * concurrent fsync/fdatasync() calls, we need them to all block on the
167 * log force before we clear the ili_fsync_fields field. This ensures
168 * that we don't get a racing sync operation that does not wait for the
169 * metadata to hit the journal before returning. If we race with
170 * clearing the ili_fsync_fields, then all that will happen is the log
171 * force will do nothing as the lsn will already be on disk. We can't
172 * race with setting ili_fsync_fields because that is done under
173 * XFS_ILOCK_EXCL, and that can't happen because we hold the lock shared
174 * until after the ili_fsync_fields is cleared.
176 xfs_ilock(ip, XFS_ILOCK_SHARED);
177 if (xfs_ipincount(ip)) {
179 (ip->i_itemp->ili_fsync_fields & ~XFS_ILOG_TIMESTAMP))
180 lsn = ip->i_itemp->ili_last_lsn;
184 error = _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, &log_flushed);
185 ip->i_itemp->ili_fsync_fields = 0;
187 xfs_iunlock(ip, XFS_ILOCK_SHARED);
190 * If we only have a single device, and the log force about was
191 * a no-op we might have to flush the data device cache here.
192 * This can only happen for fdatasync/O_DSYNC if we were overwriting
193 * an already allocated file and thus do not have any metadata to
196 if (!log_flushed && !XFS_IS_REALTIME_INODE(ip) &&
197 mp->m_logdev_targp == mp->m_ddev_targp)
198 xfs_blkdev_issue_flush(mp->m_ddev_targp);
204 xfs_file_dio_aio_read(
208 struct xfs_inode *ip = XFS_I(file_inode(iocb->ki_filp));
209 size_t count = iov_iter_count(to);
212 trace_xfs_file_direct_read(ip, count, iocb->ki_pos);
215 return 0; /* skip atime */
217 file_accessed(iocb->ki_filp);
219 xfs_ilock(ip, XFS_IOLOCK_SHARED);
220 ret = iomap_dio_rw(iocb, to, &xfs_iomap_ops, NULL);
221 xfs_iunlock(ip, XFS_IOLOCK_SHARED);
226 static noinline ssize_t
231 struct xfs_inode *ip = XFS_I(iocb->ki_filp->f_mapping->host);
232 size_t count = iov_iter_count(to);
235 trace_xfs_file_dax_read(ip, count, iocb->ki_pos);
238 return 0; /* skip atime */
240 xfs_ilock(ip, XFS_IOLOCK_SHARED);
241 ret = dax_iomap_rw(iocb, to, &xfs_iomap_ops);
242 xfs_iunlock(ip, XFS_IOLOCK_SHARED);
244 file_accessed(iocb->ki_filp);
249 xfs_file_buffered_aio_read(
253 struct xfs_inode *ip = XFS_I(file_inode(iocb->ki_filp));
256 trace_xfs_file_buffered_read(ip, iov_iter_count(to), iocb->ki_pos);
258 xfs_ilock(ip, XFS_IOLOCK_SHARED);
259 ret = generic_file_read_iter(iocb, to);
260 xfs_iunlock(ip, XFS_IOLOCK_SHARED);
270 struct inode *inode = file_inode(iocb->ki_filp);
271 struct xfs_mount *mp = XFS_I(inode)->i_mount;
274 XFS_STATS_INC(mp, xs_read_calls);
276 if (XFS_FORCED_SHUTDOWN(mp))
280 ret = xfs_file_dax_read(iocb, to);
281 else if (iocb->ki_flags & IOCB_DIRECT)
282 ret = xfs_file_dio_aio_read(iocb, to);
284 ret = xfs_file_buffered_aio_read(iocb, to);
287 XFS_STATS_ADD(mp, xs_read_bytes, ret);
292 * Zero any on disk space between the current EOF and the new, larger EOF.
294 * This handles the normal case of zeroing the remainder of the last block in
295 * the file and the unusual case of zeroing blocks out beyond the size of the
296 * file. This second case only happens with fixed size extents and when the
297 * system crashes before the inode size was updated but after blocks were
300 * Expects the iolock to be held exclusive, and will take the ilock internally.
302 int /* error (positive) */
304 struct xfs_inode *ip,
305 xfs_off_t offset, /* starting I/O offset */
306 xfs_fsize_t isize, /* current inode size */
309 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
310 ASSERT(offset > isize);
312 trace_xfs_zero_eof(ip, isize, offset - isize);
313 return xfs_zero_range(ip, isize, offset - isize, did_zeroing);
317 * Common pre-write limit and setup checks.
319 * Called with the iolocked held either shared and exclusive according to
320 * @iolock, and returns with it held. Might upgrade the iolock to exclusive
321 * if called for a direct write beyond i_size.
324 xfs_file_aio_write_checks(
326 struct iov_iter *from,
329 struct file *file = iocb->ki_filp;
330 struct inode *inode = file->f_mapping->host;
331 struct xfs_inode *ip = XFS_I(inode);
333 size_t count = iov_iter_count(from);
334 bool drained_dio = false;
337 error = generic_write_checks(iocb, from);
341 error = xfs_break_layouts(inode, iolock);
346 * For changing security info in file_remove_privs() we need i_rwsem
349 if (*iolock == XFS_IOLOCK_SHARED && !IS_NOSEC(inode)) {
350 xfs_iunlock(ip, *iolock);
351 *iolock = XFS_IOLOCK_EXCL;
352 xfs_ilock(ip, *iolock);
356 * If the offset is beyond the size of the file, we need to zero any
357 * blocks that fall between the existing EOF and the start of this
358 * write. If zeroing is needed and we are currently holding the
359 * iolock shared, we need to update it to exclusive which implies
360 * having to redo all checks before.
362 * We need to serialise against EOF updates that occur in IO
363 * completions here. We want to make sure that nobody is changing the
364 * size while we do this check until we have placed an IO barrier (i.e.
365 * hold the XFS_IOLOCK_EXCL) that prevents new IO from being dispatched.
366 * The spinlock effectively forms a memory barrier once we have the
367 * XFS_IOLOCK_EXCL so we are guaranteed to see the latest EOF value
368 * and hence be able to correctly determine if we need to run zeroing.
370 spin_lock(&ip->i_flags_lock);
371 if (iocb->ki_pos > i_size_read(inode)) {
374 spin_unlock(&ip->i_flags_lock);
376 if (*iolock == XFS_IOLOCK_SHARED) {
377 xfs_iunlock(ip, *iolock);
378 *iolock = XFS_IOLOCK_EXCL;
379 xfs_ilock(ip, *iolock);
380 iov_iter_reexpand(from, count);
383 * We now have an IO submission barrier in place, but
384 * AIO can do EOF updates during IO completion and hence
385 * we now need to wait for all of them to drain. Non-AIO
386 * DIO will have drained before we are given the
387 * XFS_IOLOCK_EXCL, and so for most cases this wait is a
390 inode_dio_wait(inode);
394 error = xfs_zero_eof(ip, iocb->ki_pos, i_size_read(inode), &zero);
398 spin_unlock(&ip->i_flags_lock);
401 * Updating the timestamps will grab the ilock again from
402 * xfs_fs_dirty_inode, so we have to call it after dropping the
403 * lock above. Eventually we should look into a way to avoid
404 * the pointless lock roundtrip.
406 if (likely(!(file->f_mode & FMODE_NOCMTIME))) {
407 error = file_update_time(file);
413 * If we're writing the file then make sure to clear the setuid and
414 * setgid bits if the process is not being run by root. This keeps
415 * people from modifying setuid and setgid binaries.
417 if (!IS_NOSEC(inode))
418 return file_remove_privs(file);
423 xfs_dio_write_end_io(
428 struct inode *inode = file_inode(iocb->ki_filp);
429 struct xfs_inode *ip = XFS_I(inode);
430 loff_t offset = iocb->ki_pos;
431 bool update_size = false;
434 trace_xfs_end_io_direct_write(ip, offset, size);
436 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
443 * We need to update the in-core inode size here so that we don't end up
444 * with the on-disk inode size being outside the in-core inode size. We
445 * have no other method of updating EOF for AIO, so always do it here
448 * We need to lock the test/set EOF update as we can be racing with
449 * other IO completions here to update the EOF. Failing to serialise
450 * here can result in EOF moving backwards and Bad Things Happen when
453 spin_lock(&ip->i_flags_lock);
454 if (offset + size > i_size_read(inode)) {
455 i_size_write(inode, offset + size);
458 spin_unlock(&ip->i_flags_lock);
460 if (flags & IOMAP_DIO_COW) {
461 error = xfs_reflink_end_cow(ip, offset, size);
466 if (flags & IOMAP_DIO_UNWRITTEN)
467 error = xfs_iomap_write_unwritten(ip, offset, size);
468 else if (update_size)
469 error = xfs_setfilesize(ip, offset, size);
475 * xfs_file_dio_aio_write - handle direct IO writes
477 * Lock the inode appropriately to prepare for and issue a direct IO write.
478 * By separating it from the buffered write path we remove all the tricky to
479 * follow locking changes and looping.
481 * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
482 * until we're sure the bytes at the new EOF have been zeroed and/or the cached
483 * pages are flushed out.
485 * In most cases the direct IO writes will be done holding IOLOCK_SHARED
486 * allowing them to be done in parallel with reads and other direct IO writes.
487 * However, if the IO is not aligned to filesystem blocks, the direct IO layer
488 * needs to do sub-block zeroing and that requires serialisation against other
489 * direct IOs to the same block. In this case we need to serialise the
490 * submission of the unaligned IOs so that we don't get racing block zeroing in
491 * the dio layer. To avoid the problem with aio, we also need to wait for
492 * outstanding IOs to complete so that unwritten extent conversion is completed
493 * before we try to map the overlapping block. This is currently implemented by
494 * hitting it with a big hammer (i.e. inode_dio_wait()).
496 * Returns with locks held indicated by @iolock and errors indicated by
497 * negative return values.
500 xfs_file_dio_aio_write(
502 struct iov_iter *from)
504 struct file *file = iocb->ki_filp;
505 struct address_space *mapping = file->f_mapping;
506 struct inode *inode = mapping->host;
507 struct xfs_inode *ip = XFS_I(inode);
508 struct xfs_mount *mp = ip->i_mount;
510 int unaligned_io = 0;
512 size_t count = iov_iter_count(from);
513 struct xfs_buftarg *target = XFS_IS_REALTIME_INODE(ip) ?
514 mp->m_rtdev_targp : mp->m_ddev_targp;
516 /* DIO must be aligned to device logical sector size */
517 if ((iocb->ki_pos | count) & target->bt_logical_sectormask)
521 * Don't take the exclusive iolock here unless the I/O is unaligned to
522 * the file system block size. We don't need to consider the EOF
523 * extension case here because xfs_file_aio_write_checks() will relock
524 * the inode as necessary for EOF zeroing cases and fill out the new
525 * inode size as appropriate.
527 if ((iocb->ki_pos & mp->m_blockmask) ||
528 ((iocb->ki_pos + count) & mp->m_blockmask)) {
532 * We can't properly handle unaligned direct I/O to reflink
533 * files yet, as we can't unshare a partial block.
535 if (xfs_is_reflink_inode(ip)) {
536 trace_xfs_reflink_bounce_dio_write(ip, iocb->ki_pos, count);
539 iolock = XFS_IOLOCK_EXCL;
541 iolock = XFS_IOLOCK_SHARED;
544 xfs_ilock(ip, iolock);
546 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
549 count = iov_iter_count(from);
552 * If we are doing unaligned IO, wait for all other IO to drain,
553 * otherwise demote the lock if we had to take the exclusive lock
554 * for other reasons in xfs_file_aio_write_checks.
557 inode_dio_wait(inode);
558 else if (iolock == XFS_IOLOCK_EXCL) {
559 xfs_ilock_demote(ip, XFS_IOLOCK_EXCL);
560 iolock = XFS_IOLOCK_SHARED;
563 trace_xfs_file_direct_write(ip, count, iocb->ki_pos);
564 ret = iomap_dio_rw(iocb, from, &xfs_iomap_ops, xfs_dio_write_end_io);
566 xfs_iunlock(ip, iolock);
569 * No fallback to buffered IO on errors for XFS, direct IO will either
570 * complete fully or fail.
572 ASSERT(ret < 0 || ret == count);
576 static noinline ssize_t
579 struct iov_iter *from)
581 struct inode *inode = iocb->ki_filp->f_mapping->host;
582 struct xfs_inode *ip = XFS_I(inode);
583 int iolock = XFS_IOLOCK_EXCL;
584 ssize_t ret, error = 0;
588 xfs_ilock(ip, iolock);
589 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
594 count = iov_iter_count(from);
596 trace_xfs_file_dax_write(ip, count, pos);
597 ret = dax_iomap_rw(iocb, from, &xfs_iomap_ops);
598 if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
599 i_size_write(inode, iocb->ki_pos);
600 error = xfs_setfilesize(ip, pos, ret);
603 xfs_iunlock(ip, iolock);
604 return error ? error : ret;
608 xfs_file_buffered_aio_write(
610 struct iov_iter *from)
612 struct file *file = iocb->ki_filp;
613 struct address_space *mapping = file->f_mapping;
614 struct inode *inode = mapping->host;
615 struct xfs_inode *ip = XFS_I(inode);
621 iolock = XFS_IOLOCK_EXCL;
622 xfs_ilock(ip, iolock);
624 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
628 /* We can write back this queue in page reclaim */
629 current->backing_dev_info = inode_to_bdi(inode);
631 trace_xfs_file_buffered_write(ip, iov_iter_count(from), iocb->ki_pos);
632 ret = iomap_file_buffered_write(iocb, from, &xfs_iomap_ops);
633 if (likely(ret >= 0))
637 * If we hit a space limit, try to free up some lingering preallocated
638 * space before returning an error. In the case of ENOSPC, first try to
639 * write back all dirty inodes to free up some of the excess reserved
640 * metadata space. This reduces the chances that the eofblocks scan
641 * waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
642 * also behaves as a filter to prevent too many eofblocks scans from
643 * running at the same time.
645 if (ret == -EDQUOT && !enospc) {
646 xfs_iunlock(ip, iolock);
647 enospc = xfs_inode_free_quota_eofblocks(ip);
650 enospc = xfs_inode_free_quota_cowblocks(ip);
654 } else if (ret == -ENOSPC && !enospc) {
655 struct xfs_eofblocks eofb = {0};
658 xfs_flush_inodes(ip->i_mount);
660 xfs_iunlock(ip, iolock);
661 eofb.eof_flags = XFS_EOF_FLAGS_SYNC;
662 xfs_icache_free_eofblocks(ip->i_mount, &eofb);
666 current->backing_dev_info = NULL;
669 xfs_iunlock(ip, iolock);
676 struct iov_iter *from)
678 struct file *file = iocb->ki_filp;
679 struct address_space *mapping = file->f_mapping;
680 struct inode *inode = mapping->host;
681 struct xfs_inode *ip = XFS_I(inode);
683 size_t ocount = iov_iter_count(from);
685 XFS_STATS_INC(ip->i_mount, xs_write_calls);
690 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
694 ret = xfs_file_dax_write(iocb, from);
695 else if (iocb->ki_flags & IOCB_DIRECT) {
697 * Allow a directio write to fall back to a buffered
698 * write *only* in the case that we're doing a reflink
699 * CoW. In all other directio scenarios we do not
700 * allow an operation to fall back to buffered mode.
702 ret = xfs_file_dio_aio_write(iocb, from);
707 ret = xfs_file_buffered_aio_write(iocb, from);
711 XFS_STATS_ADD(ip->i_mount, xs_write_bytes, ret);
713 /* Handle various SYNC-type writes */
714 ret = generic_write_sync(iocb, ret);
719 #define XFS_FALLOC_FL_SUPPORTED \
720 (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
721 FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
722 FALLOC_FL_INSERT_RANGE | FALLOC_FL_UNSHARE_RANGE)
731 struct inode *inode = file_inode(file);
732 struct xfs_inode *ip = XFS_I(inode);
734 enum xfs_prealloc_flags flags = 0;
735 uint iolock = XFS_IOLOCK_EXCL;
737 bool do_file_insert = 0;
739 if (!S_ISREG(inode->i_mode))
741 if (mode & ~XFS_FALLOC_FL_SUPPORTED)
744 xfs_ilock(ip, iolock);
745 error = xfs_break_layouts(inode, &iolock);
749 xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
750 iolock |= XFS_MMAPLOCK_EXCL;
752 if (mode & FALLOC_FL_PUNCH_HOLE) {
753 error = xfs_free_file_space(ip, offset, len);
756 } else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
757 unsigned int blksize_mask = i_blocksize(inode) - 1;
759 if (offset & blksize_mask || len & blksize_mask) {
765 * There is no need to overlap collapse range with EOF,
766 * in which case it is effectively a truncate operation
768 if (offset + len >= i_size_read(inode)) {
773 new_size = i_size_read(inode) - len;
775 error = xfs_collapse_file_space(ip, offset, len);
778 } else if (mode & FALLOC_FL_INSERT_RANGE) {
779 unsigned int blksize_mask = i_blocksize(inode) - 1;
781 new_size = i_size_read(inode) + len;
782 if (offset & blksize_mask || len & blksize_mask) {
787 /* check the new inode size does not wrap through zero */
788 if (new_size > inode->i_sb->s_maxbytes) {
793 /* Offset should be less than i_size */
794 if (offset >= i_size_read(inode)) {
800 flags |= XFS_PREALLOC_SET;
802 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
803 offset + len > i_size_read(inode)) {
804 new_size = offset + len;
805 error = inode_newsize_ok(inode, new_size);
810 if (mode & FALLOC_FL_ZERO_RANGE)
811 error = xfs_zero_file_space(ip, offset, len);
813 if (mode & FALLOC_FL_UNSHARE_RANGE) {
814 error = xfs_reflink_unshare(ip, offset, len);
818 error = xfs_alloc_file_space(ip, offset, len,
825 if (file->f_flags & O_DSYNC)
826 flags |= XFS_PREALLOC_SYNC;
828 error = xfs_update_prealloc_flags(ip, flags);
832 /* Change file size if needed */
836 iattr.ia_valid = ATTR_SIZE;
837 iattr.ia_size = new_size;
838 error = xfs_vn_setattr_size(file_dentry(file), &iattr);
844 * Perform hole insertion now that the file size has been
845 * updated so that if we crash during the operation we don't
846 * leave shifted extents past EOF and hence losing access to
847 * the data that is contained within them.
850 error = xfs_insert_file_space(ip, offset, len);
853 xfs_iunlock(ip, iolock);
858 xfs_file_clone_range(
859 struct file *file_in,
861 struct file *file_out,
865 return xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out,
870 xfs_file_dedupe_range(
871 struct file *src_file,
874 struct file *dst_file,
879 error = xfs_reflink_remap_range(src_file, loff, dst_file, dst_loff,
891 if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
893 if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
903 struct xfs_inode *ip = XFS_I(inode);
907 error = xfs_file_open(inode, file);
912 * If there are any blocks, read-ahead block 0 as we're almost
913 * certain to have the next operation be a read there.
915 mode = xfs_ilock_data_map_shared(ip);
916 if (ip->i_d.di_nextents > 0)
917 error = xfs_dir3_data_readahead(ip, 0, -1);
918 xfs_iunlock(ip, mode);
927 return xfs_release(XFS_I(inode));
933 struct dir_context *ctx)
935 struct inode *inode = file_inode(file);
936 xfs_inode_t *ip = XFS_I(inode);
940 * The Linux API doesn't pass down the total size of the buffer
941 * we read into down to the filesystem. With the filldir concept
942 * it's not needed for correct information, but the XFS dir2 leaf
943 * code wants an estimate of the buffer size to calculate it's
944 * readahead window and size the buffers used for mapping to
947 * Try to give it an estimate that's good enough, maybe at some
948 * point we can change the ->readdir prototype to include the
949 * buffer size. For now we use the current glibc buffer size.
951 bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size);
953 return xfs_readdir(ip, ctx, bufsize);
957 * This type is designed to indicate the type of offset we would like
958 * to search from page cache for xfs_seek_hole_data().
966 * Lookup the desired type of offset from the given page.
968 * On success, return true and the offset argument will point to the
969 * start of the region that was found. Otherwise this function will
970 * return false and keep the offset argument unchanged.
973 xfs_lookup_buffer_offset(
978 loff_t lastoff = page_offset(page);
980 struct buffer_head *bh, *head;
982 bh = head = page_buffers(page);
985 * Unwritten extents that have data in the page
986 * cache covering them can be identified by the
987 * BH_Unwritten state flag. Pages with multiple
988 * buffers might have a mix of holes, data and
989 * unwritten extents - any buffer with valid
990 * data in it should have BH_Uptodate flag set
993 if (buffer_unwritten(bh) ||
994 buffer_uptodate(bh)) {
995 if (type == DATA_OFF)
998 if (type == HOLE_OFF)
1006 lastoff += bh->b_size;
1007 } while ((bh = bh->b_this_page) != head);
1013 * This routine is called to find out and return a data or hole offset
1014 * from the page cache for unwritten extents according to the desired
1015 * type for xfs_seek_hole_data().
1017 * The argument offset is used to tell where we start to search from the
1018 * page cache. Map is used to figure out the end points of the range to
1021 * Return true if the desired type of offset was found, and the argument
1022 * offset is filled with that address. Otherwise, return false and keep
1026 xfs_find_get_desired_pgoff(
1027 struct inode *inode,
1028 struct xfs_bmbt_irec *map,
1032 struct xfs_inode *ip = XFS_I(inode);
1033 struct xfs_mount *mp = ip->i_mount;
1034 struct pagevec pvec;
1038 loff_t startoff = *offset;
1039 loff_t lastoff = startoff;
1042 pagevec_init(&pvec, 0);
1044 index = startoff >> PAGE_SHIFT;
1045 endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
1046 end = endoff >> PAGE_SHIFT;
1052 want = min_t(pgoff_t, end - index, PAGEVEC_SIZE);
1053 nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
1056 * No page mapped into given range. If we are searching holes
1057 * and if this is the first time we got into the loop, it means
1058 * that the given offset is landed in a hole, return it.
1060 * If we have already stepped through some block buffers to find
1061 * holes but they all contains data. In this case, the last
1062 * offset is already updated and pointed to the end of the last
1063 * mapped page, if it does not reach the endpoint to search,
1064 * that means there should be a hole between them.
1066 if (nr_pages == 0) {
1067 /* Data search found nothing */
1068 if (type == DATA_OFF)
1071 ASSERT(type == HOLE_OFF);
1072 if (lastoff == startoff || lastoff < endoff) {
1080 * At lease we found one page. If this is the first time we
1081 * step into the loop, and if the first page index offset is
1082 * greater than the given search offset, a hole was found.
1084 if (type == HOLE_OFF && lastoff == startoff &&
1085 lastoff < page_offset(pvec.pages[0])) {
1090 for (i = 0; i < nr_pages; i++) {
1091 struct page *page = pvec.pages[i];
1095 * At this point, the page may be truncated or
1096 * invalidated (changing page->mapping to NULL),
1097 * or even swizzled back from swapper_space to tmpfs
1098 * file mapping. However, page->index will not change
1099 * because we have a reference on the page.
1101 * Searching done if the page index is out of range.
1102 * If the current offset is not reaches the end of
1103 * the specified search range, there should be a hole
1106 if (page->index > end) {
1107 if (type == HOLE_OFF && lastoff < endoff) {
1116 * Page truncated or invalidated(page->mapping == NULL).
1117 * We can freely skip it and proceed to check the next
1120 if (unlikely(page->mapping != inode->i_mapping)) {
1125 if (!page_has_buffers(page)) {
1130 found = xfs_lookup_buffer_offset(page, &b_offset, type);
1133 * The found offset may be less than the start
1134 * point to search if this is the first time to
1137 *offset = max_t(loff_t, startoff, b_offset);
1143 * We either searching data but nothing was found, or
1144 * searching hole but found a data buffer. In either
1145 * case, probably the next page contains the desired
1146 * things, update the last offset to it so.
1148 lastoff = page_offset(page) + PAGE_SIZE;
1153 * The number of returned pages less than our desired, search
1154 * done. In this case, nothing was found for searching data,
1155 * but we found a hole behind the last offset.
1157 if (nr_pages < want) {
1158 if (type == HOLE_OFF) {
1165 index = pvec.pages[i - 1]->index + 1;
1166 pagevec_release(&pvec);
1167 } while (index <= end);
1170 pagevec_release(&pvec);
1175 * caller must lock inode with xfs_ilock_data_map_shared,
1176 * can we craft an appropriate ASSERT?
1178 * end is because the VFS-level lseek interface is defined such that any
1179 * offset past i_size shall return -ENXIO, but we use this for quota code
1180 * which does not maintain i_size, and we want to SEEK_DATA past i_size.
1183 __xfs_seek_hole_data(
1184 struct inode *inode,
1189 struct xfs_inode *ip = XFS_I(inode);
1190 struct xfs_mount *mp = ip->i_mount;
1191 loff_t uninitialized_var(offset);
1192 xfs_fileoff_t fsbno;
1193 xfs_filblks_t lastbno;
1202 * Try to read extents from the first block indicated
1203 * by fsbno to the end block of the file.
1205 fsbno = XFS_B_TO_FSBT(mp, start);
1206 lastbno = XFS_B_TO_FSB(mp, end);
1209 struct xfs_bmbt_irec map[2];
1213 error = xfs_bmapi_read(ip, fsbno, lastbno - fsbno, map, &nmap,
1218 /* No extents at given offset, must be beyond EOF */
1224 for (i = 0; i < nmap; i++) {
1225 offset = max_t(loff_t, start,
1226 XFS_FSB_TO_B(mp, map[i].br_startoff));
1228 /* Landed in the hole we wanted? */
1229 if (whence == SEEK_HOLE &&
1230 map[i].br_startblock == HOLESTARTBLOCK)
1233 /* Landed in the data extent we wanted? */
1234 if (whence == SEEK_DATA &&
1235 (map[i].br_startblock == DELAYSTARTBLOCK ||
1236 (map[i].br_state == XFS_EXT_NORM &&
1237 !isnullstartblock(map[i].br_startblock))))
1241 * Landed in an unwritten extent, try to search
1242 * for hole or data from page cache.
1244 if (map[i].br_state == XFS_EXT_UNWRITTEN) {
1245 if (xfs_find_get_desired_pgoff(inode, &map[i],
1246 whence == SEEK_HOLE ? HOLE_OFF : DATA_OFF,
1253 * We only received one extent out of the two requested. This
1254 * means we've hit EOF and didn't find what we are looking for.
1258 * If we were looking for a hole, set offset to
1259 * the end of the file (i.e., there is an implicit
1260 * hole at the end of any file).
1262 if (whence == SEEK_HOLE) {
1267 * If we were looking for data, it's nowhere to be found
1269 ASSERT(whence == SEEK_DATA);
1277 * Nothing was found, proceed to the next round of search
1278 * if the next reading offset is not at or beyond EOF.
1280 fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount;
1281 start = XFS_FSB_TO_B(mp, fsbno);
1283 if (whence == SEEK_HOLE) {
1287 ASSERT(whence == SEEK_DATA);
1295 * If at this point we have found the hole we wanted, the returned
1296 * offset may be bigger than the file size as it may be aligned to
1297 * page boundary for unwritten extents. We need to deal with this
1298 * situation in particular.
1300 if (whence == SEEK_HOLE)
1301 offset = min_t(loff_t, offset, end);
1315 struct inode *inode = file->f_mapping->host;
1316 struct xfs_inode *ip = XFS_I(inode);
1317 struct xfs_mount *mp = ip->i_mount;
1322 if (XFS_FORCED_SHUTDOWN(mp))
1325 lock = xfs_ilock_data_map_shared(ip);
1327 end = i_size_read(inode);
1328 offset = __xfs_seek_hole_data(inode, start, end, whence);
1334 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1337 xfs_iunlock(ip, lock);
1354 return generic_file_llseek(file, offset, whence);
1357 return xfs_seek_hole_data(file, offset, whence);
1364 * Locking for serialisation of IO during page faults. This results in a lock
1368 * sb_start_pagefault(vfs, freeze)
1369 * i_mmaplock (XFS - truncate serialisation)
1371 * i_lock (XFS - extent map serialisation)
1375 * mmap()d file has taken write protection fault and is being made writable. We
1376 * can set the page state up correctly for a writable page, which means we can
1377 * do correct delalloc accounting (ENOSPC checking!) and unwritten extent
1381 xfs_filemap_page_mkwrite(
1382 struct vm_fault *vmf)
1384 struct inode *inode = file_inode(vmf->vma->vm_file);
1387 trace_xfs_filemap_page_mkwrite(XFS_I(inode));
1389 sb_start_pagefault(inode->i_sb);
1390 file_update_time(vmf->vma->vm_file);
1391 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1393 if (IS_DAX(inode)) {
1394 ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops);
1396 ret = iomap_page_mkwrite(vmf, &xfs_iomap_ops);
1397 ret = block_page_mkwrite_return(ret);
1400 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1401 sb_end_pagefault(inode->i_sb);
1408 struct vm_fault *vmf)
1410 struct inode *inode = file_inode(vmf->vma->vm_file);
1413 trace_xfs_filemap_fault(XFS_I(inode));
1415 /* DAX can shortcut the normal fault path on write faults! */
1416 if ((vmf->flags & FAULT_FLAG_WRITE) && IS_DAX(inode))
1417 return xfs_filemap_page_mkwrite(vmf);
1419 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1421 ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops);
1423 ret = filemap_fault(vmf);
1424 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1430 * Similar to xfs_filemap_fault(), the DAX fault path can call into here on
1431 * both read and write faults. Hence we need to handle both cases. There is no
1432 * ->huge_mkwrite callout for huge pages, so we have a single function here to
1433 * handle both cases here. @flags carries the information on the type of fault
1437 xfs_filemap_huge_fault(
1438 struct vm_fault *vmf,
1439 enum page_entry_size pe_size)
1441 struct inode *inode = file_inode(vmf->vma->vm_file);
1442 struct xfs_inode *ip = XFS_I(inode);
1446 return VM_FAULT_FALLBACK;
1448 trace_xfs_filemap_huge_fault(ip);
1450 if (vmf->flags & FAULT_FLAG_WRITE) {
1451 sb_start_pagefault(inode->i_sb);
1452 file_update_time(vmf->vma->vm_file);
1455 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1456 ret = dax_iomap_fault(vmf, pe_size, &xfs_iomap_ops);
1457 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1459 if (vmf->flags & FAULT_FLAG_WRITE)
1460 sb_end_pagefault(inode->i_sb);
1466 * pfn_mkwrite was originally inteneded to ensure we capture time stamp
1467 * updates on write faults. In reality, it's need to serialise against
1468 * truncate similar to page_mkwrite. Hence we cycle the XFS_MMAPLOCK_SHARED
1469 * to ensure we serialise the fault barrier in place.
1472 xfs_filemap_pfn_mkwrite(
1473 struct vm_fault *vmf)
1476 struct inode *inode = file_inode(vmf->vma->vm_file);
1477 struct xfs_inode *ip = XFS_I(inode);
1478 int ret = VM_FAULT_NOPAGE;
1481 trace_xfs_filemap_pfn_mkwrite(ip);
1483 sb_start_pagefault(inode->i_sb);
1484 file_update_time(vmf->vma->vm_file);
1486 /* check if the faulting page hasn't raced with truncate */
1487 xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
1488 size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
1489 if (vmf->pgoff >= size)
1490 ret = VM_FAULT_SIGBUS;
1491 else if (IS_DAX(inode))
1492 ret = dax_pfn_mkwrite(vmf);
1493 xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
1494 sb_end_pagefault(inode->i_sb);
1499 static const struct vm_operations_struct xfs_file_vm_ops = {
1500 .fault = xfs_filemap_fault,
1501 .huge_fault = xfs_filemap_huge_fault,
1502 .map_pages = filemap_map_pages,
1503 .page_mkwrite = xfs_filemap_page_mkwrite,
1504 .pfn_mkwrite = xfs_filemap_pfn_mkwrite,
1510 struct vm_area_struct *vma)
1512 file_accessed(filp);
1513 vma->vm_ops = &xfs_file_vm_ops;
1514 if (IS_DAX(file_inode(filp)))
1515 vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
1519 const struct file_operations xfs_file_operations = {
1520 .llseek = xfs_file_llseek,
1521 .read_iter = xfs_file_read_iter,
1522 .write_iter = xfs_file_write_iter,
1523 .splice_read = generic_file_splice_read,
1524 .splice_write = iter_file_splice_write,
1525 .unlocked_ioctl = xfs_file_ioctl,
1526 #ifdef CONFIG_COMPAT
1527 .compat_ioctl = xfs_file_compat_ioctl,
1529 .mmap = xfs_file_mmap,
1530 .open = xfs_file_open,
1531 .release = xfs_file_release,
1532 .fsync = xfs_file_fsync,
1533 .get_unmapped_area = thp_get_unmapped_area,
1534 .fallocate = xfs_file_fallocate,
1535 .clone_file_range = xfs_file_clone_range,
1536 .dedupe_file_range = xfs_file_dedupe_range,
1539 const struct file_operations xfs_dir_file_operations = {
1540 .open = xfs_dir_open,
1541 .read = generic_read_dir,
1542 .iterate_shared = xfs_file_readdir,
1543 .llseek = generic_file_llseek,
1544 .unlocked_ioctl = xfs_file_ioctl,
1545 #ifdef CONFIG_COMPAT
1546 .compat_ioctl = xfs_file_compat_ioctl,
1548 .fsync = xfs_dir_fsync,