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,