Version:  2.0.40 2.2.26 2.4.37 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10

Linux/fs/xfs/xfs_file.c

  1 /*
  2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
  3  * All Rights Reserved.
  4  *
  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.
  8  *
  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.
 13  *
 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
 17  */
 18 #include "xfs.h"
 19 #include "xfs_fs.h"
 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_sb.h"
 25 #include "xfs_ag.h"
 26 #include "xfs_mount.h"
 27 #include "xfs_da_format.h"
 28 #include "xfs_da_btree.h"
 29 #include "xfs_inode.h"
 30 #include "xfs_trans.h"
 31 #include "xfs_inode_item.h"
 32 #include "xfs_bmap.h"
 33 #include "xfs_bmap_util.h"
 34 #include "xfs_error.h"
 35 #include "xfs_dir2.h"
 36 #include "xfs_dir2_priv.h"
 37 #include "xfs_ioctl.h"
 38 #include "xfs_trace.h"
 39 #include "xfs_log.h"
 40 #include "xfs_dinode.h"
 41 #include "xfs_icache.h"
 42 
 43 #include <linux/aio.h>
 44 #include <linux/dcache.h>
 45 #include <linux/falloc.h>
 46 #include <linux/pagevec.h>
 47 
 48 static const struct vm_operations_struct xfs_file_vm_ops;
 49 
 50 /*
 51  * Locking primitives for read and write IO paths to ensure we consistently use
 52  * and order the inode->i_mutex, ip->i_lock and ip->i_iolock.
 53  */
 54 static inline void
 55 xfs_rw_ilock(
 56         struct xfs_inode        *ip,
 57         int                     type)
 58 {
 59         if (type & XFS_IOLOCK_EXCL)
 60                 mutex_lock(&VFS_I(ip)->i_mutex);
 61         xfs_ilock(ip, type);
 62 }
 63 
 64 static inline void
 65 xfs_rw_iunlock(
 66         struct xfs_inode        *ip,
 67         int                     type)
 68 {
 69         xfs_iunlock(ip, type);
 70         if (type & XFS_IOLOCK_EXCL)
 71                 mutex_unlock(&VFS_I(ip)->i_mutex);
 72 }
 73 
 74 static inline void
 75 xfs_rw_ilock_demote(
 76         struct xfs_inode        *ip,
 77         int                     type)
 78 {
 79         xfs_ilock_demote(ip, type);
 80         if (type & XFS_IOLOCK_EXCL)
 81                 mutex_unlock(&VFS_I(ip)->i_mutex);
 82 }
 83 
 84 /*
 85  *      xfs_iozero
 86  *
 87  *      xfs_iozero clears the specified range of buffer supplied,
 88  *      and marks all the affected blocks as valid and modified.  If
 89  *      an affected block is not allocated, it will be allocated.  If
 90  *      an affected block is not completely overwritten, and is not
 91  *      valid before the operation, it will be read from disk before
 92  *      being partially zeroed.
 93  */
 94 int
 95 xfs_iozero(
 96         struct xfs_inode        *ip,    /* inode                        */
 97         loff_t                  pos,    /* offset in file               */
 98         size_t                  count)  /* size of data to zero         */
 99 {
100         struct page             *page;
101         struct address_space    *mapping;
102         int                     status;
103 
104         mapping = VFS_I(ip)->i_mapping;
105         do {
106                 unsigned offset, bytes;
107                 void *fsdata;
108 
109                 offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
110                 bytes = PAGE_CACHE_SIZE - offset;
111                 if (bytes > count)
112                         bytes = count;
113 
114                 status = pagecache_write_begin(NULL, mapping, pos, bytes,
115                                         AOP_FLAG_UNINTERRUPTIBLE,
116                                         &page, &fsdata);
117                 if (status)
118                         break;
119 
120                 zero_user(page, offset, bytes);
121 
122                 status = pagecache_write_end(NULL, mapping, pos, bytes, bytes,
123                                         page, fsdata);
124                 WARN_ON(status <= 0); /* can't return less than zero! */
125                 pos += bytes;
126                 count -= bytes;
127                 status = 0;
128         } while (count);
129 
130         return (-status);
131 }
132 
133 /*
134  * Fsync operations on directories are much simpler than on regular files,
135  * as there is no file data to flush, and thus also no need for explicit
136  * cache flush operations, and there are no non-transaction metadata updates
137  * on directories either.
138  */
139 STATIC int
140 xfs_dir_fsync(
141         struct file             *file,
142         loff_t                  start,
143         loff_t                  end,
144         int                     datasync)
145 {
146         struct xfs_inode        *ip = XFS_I(file->f_mapping->host);
147         struct xfs_mount        *mp = ip->i_mount;
148         xfs_lsn_t               lsn = 0;
149 
150         trace_xfs_dir_fsync(ip);
151 
152         xfs_ilock(ip, XFS_ILOCK_SHARED);
153         if (xfs_ipincount(ip))
154                 lsn = ip->i_itemp->ili_last_lsn;
155         xfs_iunlock(ip, XFS_ILOCK_SHARED);
156 
157         if (!lsn)
158                 return 0;
159         return _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, NULL);
160 }
161 
162 STATIC int
163 xfs_file_fsync(
164         struct file             *file,
165         loff_t                  start,
166         loff_t                  end,
167         int                     datasync)
168 {
169         struct inode            *inode = file->f_mapping->host;
170         struct xfs_inode        *ip = XFS_I(inode);
171         struct xfs_mount        *mp = ip->i_mount;
172         int                     error = 0;
173         int                     log_flushed = 0;
174         xfs_lsn_t               lsn = 0;
175 
176         trace_xfs_file_fsync(ip);
177 
178         error = filemap_write_and_wait_range(inode->i_mapping, start, end);
179         if (error)
180                 return error;
181 
182         if (XFS_FORCED_SHUTDOWN(mp))
183                 return -EIO;
184 
185         xfs_iflags_clear(ip, XFS_ITRUNCATED);
186 
187         if (mp->m_flags & XFS_MOUNT_BARRIER) {
188                 /*
189                  * If we have an RT and/or log subvolume we need to make sure
190                  * to flush the write cache the device used for file data
191                  * first.  This is to ensure newly written file data make
192                  * it to disk before logging the new inode size in case of
193                  * an extending write.
194                  */
195                 if (XFS_IS_REALTIME_INODE(ip))
196                         xfs_blkdev_issue_flush(mp->m_rtdev_targp);
197                 else if (mp->m_logdev_targp != mp->m_ddev_targp)
198                         xfs_blkdev_issue_flush(mp->m_ddev_targp);
199         }
200 
201         /*
202          * All metadata updates are logged, which means that we just have
203          * to flush the log up to the latest LSN that touched the inode.
204          */
205         xfs_ilock(ip, XFS_ILOCK_SHARED);
206         if (xfs_ipincount(ip)) {
207                 if (!datasync ||
208                     (ip->i_itemp->ili_fields & ~XFS_ILOG_TIMESTAMP))
209                         lsn = ip->i_itemp->ili_last_lsn;
210         }
211         xfs_iunlock(ip, XFS_ILOCK_SHARED);
212 
213         if (lsn)
214                 error = _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, &log_flushed);
215 
216         /*
217          * If we only have a single device, and the log force about was
218          * a no-op we might have to flush the data device cache here.
219          * This can only happen for fdatasync/O_DSYNC if we were overwriting
220          * an already allocated file and thus do not have any metadata to
221          * commit.
222          */
223         if ((mp->m_flags & XFS_MOUNT_BARRIER) &&
224             mp->m_logdev_targp == mp->m_ddev_targp &&
225             !XFS_IS_REALTIME_INODE(ip) &&
226             !log_flushed)
227                 xfs_blkdev_issue_flush(mp->m_ddev_targp);
228 
229         return error;
230 }
231 
232 STATIC ssize_t
233 xfs_file_read_iter(
234         struct kiocb            *iocb,
235         struct iov_iter         *to)
236 {
237         struct file             *file = iocb->ki_filp;
238         struct inode            *inode = file->f_mapping->host;
239         struct xfs_inode        *ip = XFS_I(inode);
240         struct xfs_mount        *mp = ip->i_mount;
241         size_t                  size = iov_iter_count(to);
242         ssize_t                 ret = 0;
243         int                     ioflags = 0;
244         xfs_fsize_t             n;
245         loff_t                  pos = iocb->ki_pos;
246 
247         XFS_STATS_INC(xs_read_calls);
248 
249         if (unlikely(file->f_flags & O_DIRECT))
250                 ioflags |= XFS_IO_ISDIRECT;
251         if (file->f_mode & FMODE_NOCMTIME)
252                 ioflags |= XFS_IO_INVIS;
253 
254         if (unlikely(ioflags & XFS_IO_ISDIRECT)) {
255                 xfs_buftarg_t   *target =
256                         XFS_IS_REALTIME_INODE(ip) ?
257                                 mp->m_rtdev_targp : mp->m_ddev_targp;
258                 /* DIO must be aligned to device logical sector size */
259                 if ((pos | size) & target->bt_logical_sectormask) {
260                         if (pos == i_size_read(inode))
261                                 return 0;
262                         return -EINVAL;
263                 }
264         }
265 
266         n = mp->m_super->s_maxbytes - pos;
267         if (n <= 0 || size == 0)
268                 return 0;
269 
270         if (n < size)
271                 size = n;
272 
273         if (XFS_FORCED_SHUTDOWN(mp))
274                 return -EIO;
275 
276         /*
277          * Locking is a bit tricky here. If we take an exclusive lock
278          * for direct IO, we effectively serialise all new concurrent
279          * read IO to this file and block it behind IO that is currently in
280          * progress because IO in progress holds the IO lock shared. We only
281          * need to hold the lock exclusive to blow away the page cache, so
282          * only take lock exclusively if the page cache needs invalidation.
283          * This allows the normal direct IO case of no page cache pages to
284          * proceeed concurrently without serialisation.
285          */
286         xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
287         if ((ioflags & XFS_IO_ISDIRECT) && inode->i_mapping->nrpages) {
288                 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
289                 xfs_rw_ilock(ip, XFS_IOLOCK_EXCL);
290 
291                 if (inode->i_mapping->nrpages) {
292                         ret = filemap_write_and_wait_range(
293                                                         VFS_I(ip)->i_mapping,
294                                                         pos, pos + size - 1);
295                         if (ret) {
296                                 xfs_rw_iunlock(ip, XFS_IOLOCK_EXCL);
297                                 return ret;
298                         }
299 
300                         /*
301                          * Invalidate whole pages. This can return an error if
302                          * we fail to invalidate a page, but this should never
303                          * happen on XFS. Warn if it does fail.
304                          */
305                         ret = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
306                                         pos >> PAGE_CACHE_SHIFT,
307                                         (pos + size - 1) >> PAGE_CACHE_SHIFT);
308                         WARN_ON_ONCE(ret);
309                         ret = 0;
310                 }
311                 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
312         }
313 
314         trace_xfs_file_read(ip, size, pos, ioflags);
315 
316         ret = generic_file_read_iter(iocb, to);
317         if (ret > 0)
318                 XFS_STATS_ADD(xs_read_bytes, ret);
319 
320         xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
321         return ret;
322 }
323 
324 STATIC ssize_t
325 xfs_file_splice_read(
326         struct file             *infilp,
327         loff_t                  *ppos,
328         struct pipe_inode_info  *pipe,
329         size_t                  count,
330         unsigned int            flags)
331 {
332         struct xfs_inode        *ip = XFS_I(infilp->f_mapping->host);
333         int                     ioflags = 0;
334         ssize_t                 ret;
335 
336         XFS_STATS_INC(xs_read_calls);
337 
338         if (infilp->f_mode & FMODE_NOCMTIME)
339                 ioflags |= XFS_IO_INVIS;
340 
341         if (XFS_FORCED_SHUTDOWN(ip->i_mount))
342                 return -EIO;
343 
344         xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
345 
346         trace_xfs_file_splice_read(ip, count, *ppos, ioflags);
347 
348         ret = generic_file_splice_read(infilp, ppos, pipe, count, flags);
349         if (ret > 0)
350                 XFS_STATS_ADD(xs_read_bytes, ret);
351 
352         xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
353         return ret;
354 }
355 
356 /*
357  * This routine is called to handle zeroing any space in the last block of the
358  * file that is beyond the EOF.  We do this since the size is being increased
359  * without writing anything to that block and we don't want to read the
360  * garbage on the disk.
361  */
362 STATIC int                              /* error (positive) */
363 xfs_zero_last_block(
364         struct xfs_inode        *ip,
365         xfs_fsize_t             offset,
366         xfs_fsize_t             isize)
367 {
368         struct xfs_mount        *mp = ip->i_mount;
369         xfs_fileoff_t           last_fsb = XFS_B_TO_FSBT(mp, isize);
370         int                     zero_offset = XFS_B_FSB_OFFSET(mp, isize);
371         int                     zero_len;
372         int                     nimaps = 1;
373         int                     error = 0;
374         struct xfs_bmbt_irec    imap;
375 
376         xfs_ilock(ip, XFS_ILOCK_EXCL);
377         error = xfs_bmapi_read(ip, last_fsb, 1, &imap, &nimaps, 0);
378         xfs_iunlock(ip, XFS_ILOCK_EXCL);
379         if (error)
380                 return error;
381 
382         ASSERT(nimaps > 0);
383 
384         /*
385          * If the block underlying isize is just a hole, then there
386          * is nothing to zero.
387          */
388         if (imap.br_startblock == HOLESTARTBLOCK)
389                 return 0;
390 
391         zero_len = mp->m_sb.sb_blocksize - zero_offset;
392         if (isize + zero_len > offset)
393                 zero_len = offset - isize;
394         return xfs_iozero(ip, isize, zero_len);
395 }
396 
397 /*
398  * Zero any on disk space between the current EOF and the new, larger EOF.
399  *
400  * This handles the normal case of zeroing the remainder of the last block in
401  * the file and the unusual case of zeroing blocks out beyond the size of the
402  * file.  This second case only happens with fixed size extents and when the
403  * system crashes before the inode size was updated but after blocks were
404  * allocated.
405  *
406  * Expects the iolock to be held exclusive, and will take the ilock internally.
407  */
408 int                                     /* error (positive) */
409 xfs_zero_eof(
410         struct xfs_inode        *ip,
411         xfs_off_t               offset,         /* starting I/O offset */
412         xfs_fsize_t             isize)          /* current inode size */
413 {
414         struct xfs_mount        *mp = ip->i_mount;
415         xfs_fileoff_t           start_zero_fsb;
416         xfs_fileoff_t           end_zero_fsb;
417         xfs_fileoff_t           zero_count_fsb;
418         xfs_fileoff_t           last_fsb;
419         xfs_fileoff_t           zero_off;
420         xfs_fsize_t             zero_len;
421         int                     nimaps;
422         int                     error = 0;
423         struct xfs_bmbt_irec    imap;
424 
425         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
426         ASSERT(offset > isize);
427 
428         /*
429          * First handle zeroing the block on which isize resides.
430          *
431          * We only zero a part of that block so it is handled specially.
432          */
433         if (XFS_B_FSB_OFFSET(mp, isize) != 0) {
434                 error = xfs_zero_last_block(ip, offset, isize);
435                 if (error)
436                         return error;
437         }
438 
439         /*
440          * Calculate the range between the new size and the old where blocks
441          * needing to be zeroed may exist.
442          *
443          * To get the block where the last byte in the file currently resides,
444          * we need to subtract one from the size and truncate back to a block
445          * boundary.  We subtract 1 in case the size is exactly on a block
446          * boundary.
447          */
448         last_fsb = isize ? XFS_B_TO_FSBT(mp, isize - 1) : (xfs_fileoff_t)-1;
449         start_zero_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)isize);
450         end_zero_fsb = XFS_B_TO_FSBT(mp, offset - 1);
451         ASSERT((xfs_sfiloff_t)last_fsb < (xfs_sfiloff_t)start_zero_fsb);
452         if (last_fsb == end_zero_fsb) {
453                 /*
454                  * The size was only incremented on its last block.
455                  * We took care of that above, so just return.
456                  */
457                 return 0;
458         }
459 
460         ASSERT(start_zero_fsb <= end_zero_fsb);
461         while (start_zero_fsb <= end_zero_fsb) {
462                 nimaps = 1;
463                 zero_count_fsb = end_zero_fsb - start_zero_fsb + 1;
464 
465                 xfs_ilock(ip, XFS_ILOCK_EXCL);
466                 error = xfs_bmapi_read(ip, start_zero_fsb, zero_count_fsb,
467                                           &imap, &nimaps, 0);
468                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
469                 if (error)
470                         return error;
471 
472                 ASSERT(nimaps > 0);
473 
474                 if (imap.br_state == XFS_EXT_UNWRITTEN ||
475                     imap.br_startblock == HOLESTARTBLOCK) {
476                         start_zero_fsb = imap.br_startoff + imap.br_blockcount;
477                         ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
478                         continue;
479                 }
480 
481                 /*
482                  * There are blocks we need to zero.
483                  */
484                 zero_off = XFS_FSB_TO_B(mp, start_zero_fsb);
485                 zero_len = XFS_FSB_TO_B(mp, imap.br_blockcount);
486 
487                 if ((zero_off + zero_len) > offset)
488                         zero_len = offset - zero_off;
489 
490                 error = xfs_iozero(ip, zero_off, zero_len);
491                 if (error)
492                         return error;
493 
494                 start_zero_fsb = imap.br_startoff + imap.br_blockcount;
495                 ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
496         }
497 
498         return 0;
499 }
500 
501 /*
502  * Common pre-write limit and setup checks.
503  *
504  * Called with the iolocked held either shared and exclusive according to
505  * @iolock, and returns with it held.  Might upgrade the iolock to exclusive
506  * if called for a direct write beyond i_size.
507  */
508 STATIC ssize_t
509 xfs_file_aio_write_checks(
510         struct file             *file,
511         loff_t                  *pos,
512         size_t                  *count,
513         int                     *iolock)
514 {
515         struct inode            *inode = file->f_mapping->host;
516         struct xfs_inode        *ip = XFS_I(inode);
517         int                     error = 0;
518 
519 restart:
520         error = generic_write_checks(file, pos, count, S_ISBLK(inode->i_mode));
521         if (error)
522                 return error;
523 
524         /*
525          * If the offset is beyond the size of the file, we need to zero any
526          * blocks that fall between the existing EOF and the start of this
527          * write.  If zeroing is needed and we are currently holding the
528          * iolock shared, we need to update it to exclusive which implies
529          * having to redo all checks before.
530          */
531         if (*pos > i_size_read(inode)) {
532                 if (*iolock == XFS_IOLOCK_SHARED) {
533                         xfs_rw_iunlock(ip, *iolock);
534                         *iolock = XFS_IOLOCK_EXCL;
535                         xfs_rw_ilock(ip, *iolock);
536                         goto restart;
537                 }
538                 error = xfs_zero_eof(ip, *pos, i_size_read(inode));
539                 if (error)
540                         return error;
541         }
542 
543         /*
544          * Updating the timestamps will grab the ilock again from
545          * xfs_fs_dirty_inode, so we have to call it after dropping the
546          * lock above.  Eventually we should look into a way to avoid
547          * the pointless lock roundtrip.
548          */
549         if (likely(!(file->f_mode & FMODE_NOCMTIME))) {
550                 error = file_update_time(file);
551                 if (error)
552                         return error;
553         }
554 
555         /*
556          * If we're writing the file then make sure to clear the setuid and
557          * setgid bits if the process is not being run by root.  This keeps
558          * people from modifying setuid and setgid binaries.
559          */
560         return file_remove_suid(file);
561 }
562 
563 /*
564  * xfs_file_dio_aio_write - handle direct IO writes
565  *
566  * Lock the inode appropriately to prepare for and issue a direct IO write.
567  * By separating it from the buffered write path we remove all the tricky to
568  * follow locking changes and looping.
569  *
570  * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
571  * until we're sure the bytes at the new EOF have been zeroed and/or the cached
572  * pages are flushed out.
573  *
574  * In most cases the direct IO writes will be done holding IOLOCK_SHARED
575  * allowing them to be done in parallel with reads and other direct IO writes.
576  * However, if the IO is not aligned to filesystem blocks, the direct IO layer
577  * needs to do sub-block zeroing and that requires serialisation against other
578  * direct IOs to the same block. In this case we need to serialise the
579  * submission of the unaligned IOs so that we don't get racing block zeroing in
580  * the dio layer.  To avoid the problem with aio, we also need to wait for
581  * outstanding IOs to complete so that unwritten extent conversion is completed
582  * before we try to map the overlapping block. This is currently implemented by
583  * hitting it with a big hammer (i.e. inode_dio_wait()).
584  *
585  * Returns with locks held indicated by @iolock and errors indicated by
586  * negative return values.
587  */
588 STATIC ssize_t
589 xfs_file_dio_aio_write(
590         struct kiocb            *iocb,
591         struct iov_iter         *from)
592 {
593         struct file             *file = iocb->ki_filp;
594         struct address_space    *mapping = file->f_mapping;
595         struct inode            *inode = mapping->host;
596         struct xfs_inode        *ip = XFS_I(inode);
597         struct xfs_mount        *mp = ip->i_mount;
598         ssize_t                 ret = 0;
599         int                     unaligned_io = 0;
600         int                     iolock;
601         size_t                  count = iov_iter_count(from);
602         loff_t                  pos = iocb->ki_pos;
603         struct xfs_buftarg      *target = XFS_IS_REALTIME_INODE(ip) ?
604                                         mp->m_rtdev_targp : mp->m_ddev_targp;
605 
606         /* DIO must be aligned to device logical sector size */
607         if ((pos | count) & target->bt_logical_sectormask)
608                 return -EINVAL;
609 
610         /* "unaligned" here means not aligned to a filesystem block */
611         if ((pos & mp->m_blockmask) || ((pos + count) & mp->m_blockmask))
612                 unaligned_io = 1;
613 
614         /*
615          * We don't need to take an exclusive lock unless there page cache needs
616          * to be invalidated or unaligned IO is being executed. We don't need to
617          * consider the EOF extension case here because
618          * xfs_file_aio_write_checks() will relock the inode as necessary for
619          * EOF zeroing cases and fill out the new inode size as appropriate.
620          */
621         if (unaligned_io || mapping->nrpages)
622                 iolock = XFS_IOLOCK_EXCL;
623         else
624                 iolock = XFS_IOLOCK_SHARED;
625         xfs_rw_ilock(ip, iolock);
626 
627         /*
628          * Recheck if there are cached pages that need invalidate after we got
629          * the iolock to protect against other threads adding new pages while
630          * we were waiting for the iolock.
631          */
632         if (mapping->nrpages && iolock == XFS_IOLOCK_SHARED) {
633                 xfs_rw_iunlock(ip, iolock);
634                 iolock = XFS_IOLOCK_EXCL;
635                 xfs_rw_ilock(ip, iolock);
636         }
637 
638         ret = xfs_file_aio_write_checks(file, &pos, &count, &iolock);
639         if (ret)
640                 goto out;
641         iov_iter_truncate(from, count);
642 
643         if (mapping->nrpages) {
644                 ret = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
645                                                     pos, pos + count - 1);
646                 if (ret)
647                         goto out;
648                 /*
649                  * Invalidate whole pages. This can return an error if
650                  * we fail to invalidate a page, but this should never
651                  * happen on XFS. Warn if it does fail.
652                  */
653                 ret = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
654                                         pos >> PAGE_CACHE_SHIFT,
655                                         (pos + count - 1) >> PAGE_CACHE_SHIFT);
656                 WARN_ON_ONCE(ret);
657                 ret = 0;
658         }
659 
660         /*
661          * If we are doing unaligned IO, wait for all other IO to drain,
662          * otherwise demote the lock if we had to flush cached pages
663          */
664         if (unaligned_io)
665                 inode_dio_wait(inode);
666         else if (iolock == XFS_IOLOCK_EXCL) {
667                 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
668                 iolock = XFS_IOLOCK_SHARED;
669         }
670 
671         trace_xfs_file_direct_write(ip, count, iocb->ki_pos, 0);
672         ret = generic_file_direct_write(iocb, from, pos);
673 
674 out:
675         xfs_rw_iunlock(ip, iolock);
676 
677         /* No fallback to buffered IO on errors for XFS. */
678         ASSERT(ret < 0 || ret == count);
679         return ret;
680 }
681 
682 STATIC ssize_t
683 xfs_file_buffered_aio_write(
684         struct kiocb            *iocb,
685         struct iov_iter         *from)
686 {
687         struct file             *file = iocb->ki_filp;
688         struct address_space    *mapping = file->f_mapping;
689         struct inode            *inode = mapping->host;
690         struct xfs_inode        *ip = XFS_I(inode);
691         ssize_t                 ret;
692         int                     enospc = 0;
693         int                     iolock = XFS_IOLOCK_EXCL;
694         loff_t                  pos = iocb->ki_pos;
695         size_t                  count = iov_iter_count(from);
696 
697         xfs_rw_ilock(ip, iolock);
698 
699         ret = xfs_file_aio_write_checks(file, &pos, &count, &iolock);
700         if (ret)
701                 goto out;
702 
703         iov_iter_truncate(from, count);
704         /* We can write back this queue in page reclaim */
705         current->backing_dev_info = mapping->backing_dev_info;
706 
707 write_retry:
708         trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, 0);
709         ret = generic_perform_write(file, from, pos);
710         if (likely(ret >= 0))
711                 iocb->ki_pos = pos + ret;
712 
713         /*
714          * If we hit a space limit, try to free up some lingering preallocated
715          * space before returning an error. In the case of ENOSPC, first try to
716          * write back all dirty inodes to free up some of the excess reserved
717          * metadata space. This reduces the chances that the eofblocks scan
718          * waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
719          * also behaves as a filter to prevent too many eofblocks scans from
720          * running at the same time.
721          */
722         if (ret == -EDQUOT && !enospc) {
723                 enospc = xfs_inode_free_quota_eofblocks(ip);
724                 if (enospc)
725                         goto write_retry;
726         } else if (ret == -ENOSPC && !enospc) {
727                 struct xfs_eofblocks eofb = {0};
728 
729                 enospc = 1;
730                 xfs_flush_inodes(ip->i_mount);
731                 eofb.eof_scan_owner = ip->i_ino; /* for locking */
732                 eofb.eof_flags = XFS_EOF_FLAGS_SYNC;
733                 xfs_icache_free_eofblocks(ip->i_mount, &eofb);
734                 goto write_retry;
735         }
736 
737         current->backing_dev_info = NULL;
738 out:
739         xfs_rw_iunlock(ip, iolock);
740         return ret;
741 }
742 
743 STATIC ssize_t
744 xfs_file_write_iter(
745         struct kiocb            *iocb,
746         struct iov_iter         *from)
747 {
748         struct file             *file = iocb->ki_filp;
749         struct address_space    *mapping = file->f_mapping;
750         struct inode            *inode = mapping->host;
751         struct xfs_inode        *ip = XFS_I(inode);
752         ssize_t                 ret;
753         size_t                  ocount = iov_iter_count(from);
754 
755         XFS_STATS_INC(xs_write_calls);
756 
757         if (ocount == 0)
758                 return 0;
759 
760         if (XFS_FORCED_SHUTDOWN(ip->i_mount))
761                 return -EIO;
762 
763         if (unlikely(file->f_flags & O_DIRECT))
764                 ret = xfs_file_dio_aio_write(iocb, from);
765         else
766                 ret = xfs_file_buffered_aio_write(iocb, from);
767 
768         if (ret > 0) {
769                 ssize_t err;
770 
771                 XFS_STATS_ADD(xs_write_bytes, ret);
772 
773                 /* Handle various SYNC-type writes */
774                 err = generic_write_sync(file, iocb->ki_pos - ret, ret);
775                 if (err < 0)
776                         ret = err;
777         }
778         return ret;
779 }
780 
781 STATIC long
782 xfs_file_fallocate(
783         struct file             *file,
784         int                     mode,
785         loff_t                  offset,
786         loff_t                  len)
787 {
788         struct inode            *inode = file_inode(file);
789         struct xfs_inode        *ip = XFS_I(inode);
790         struct xfs_trans        *tp;
791         long                    error;
792         loff_t                  new_size = 0;
793 
794         if (!S_ISREG(inode->i_mode))
795                 return -EINVAL;
796         if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
797                      FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))
798                 return -EOPNOTSUPP;
799 
800         xfs_ilock(ip, XFS_IOLOCK_EXCL);
801         if (mode & FALLOC_FL_PUNCH_HOLE) {
802                 error = xfs_free_file_space(ip, offset, len);
803                 if (error)
804                         goto out_unlock;
805         } else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
806                 unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
807 
808                 if (offset & blksize_mask || len & blksize_mask) {
809                         error = -EINVAL;
810                         goto out_unlock;
811                 }
812 
813                 /*
814                  * There is no need to overlap collapse range with EOF,
815                  * in which case it is effectively a truncate operation
816                  */
817                 if (offset + len >= i_size_read(inode)) {
818                         error = -EINVAL;
819                         goto out_unlock;
820                 }
821 
822                 new_size = i_size_read(inode) - len;
823 
824                 error = xfs_collapse_file_space(ip, offset, len);
825                 if (error)
826                         goto out_unlock;
827         } else {
828                 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
829                     offset + len > i_size_read(inode)) {
830                         new_size = offset + len;
831                         error = inode_newsize_ok(inode, new_size);
832                         if (error)
833                                 goto out_unlock;
834                 }
835 
836                 if (mode & FALLOC_FL_ZERO_RANGE)
837                         error = xfs_zero_file_space(ip, offset, len);
838                 else
839                         error = xfs_alloc_file_space(ip, offset, len,
840                                                      XFS_BMAPI_PREALLOC);
841                 if (error)
842                         goto out_unlock;
843         }
844 
845         tp = xfs_trans_alloc(ip->i_mount, XFS_TRANS_WRITEID);
846         error = xfs_trans_reserve(tp, &M_RES(ip->i_mount)->tr_writeid, 0, 0);
847         if (error) {
848                 xfs_trans_cancel(tp, 0);
849                 goto out_unlock;
850         }
851 
852         xfs_ilock(ip, XFS_ILOCK_EXCL);
853         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
854         ip->i_d.di_mode &= ~S_ISUID;
855         if (ip->i_d.di_mode & S_IXGRP)
856                 ip->i_d.di_mode &= ~S_ISGID;
857 
858         if (!(mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_COLLAPSE_RANGE)))
859                 ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
860 
861         xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
862         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
863 
864         if (file->f_flags & O_DSYNC)
865                 xfs_trans_set_sync(tp);
866         error = xfs_trans_commit(tp, 0);
867         if (error)
868                 goto out_unlock;
869 
870         /* Change file size if needed */
871         if (new_size) {
872                 struct iattr iattr;
873 
874                 iattr.ia_valid = ATTR_SIZE;
875                 iattr.ia_size = new_size;
876                 error = xfs_setattr_size(ip, &iattr);
877         }
878 
879 out_unlock:
880         xfs_iunlock(ip, XFS_IOLOCK_EXCL);
881         return error;
882 }
883 
884 
885 STATIC int
886 xfs_file_open(
887         struct inode    *inode,
888         struct file     *file)
889 {
890         if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
891                 return -EFBIG;
892         if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
893                 return -EIO;
894         return 0;
895 }
896 
897 STATIC int
898 xfs_dir_open(
899         struct inode    *inode,
900         struct file     *file)
901 {
902         struct xfs_inode *ip = XFS_I(inode);
903         int             mode;
904         int             error;
905 
906         error = xfs_file_open(inode, file);
907         if (error)
908                 return error;
909 
910         /*
911          * If there are any blocks, read-ahead block 0 as we're almost
912          * certain to have the next operation be a read there.
913          */
914         mode = xfs_ilock_data_map_shared(ip);
915         if (ip->i_d.di_nextents > 0)
916                 xfs_dir3_data_readahead(ip, 0, -1);
917         xfs_iunlock(ip, mode);
918         return 0;
919 }
920 
921 STATIC int
922 xfs_file_release(
923         struct inode    *inode,
924         struct file     *filp)
925 {
926         return xfs_release(XFS_I(inode));
927 }
928 
929 STATIC int
930 xfs_file_readdir(
931         struct file     *file,
932         struct dir_context *ctx)
933 {
934         struct inode    *inode = file_inode(file);
935         xfs_inode_t     *ip = XFS_I(inode);
936         int             error;
937         size_t          bufsize;
938 
939         /*
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
945          * physical blocks.
946          *
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.
950          */
951         bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size);
952 
953         error = xfs_readdir(ip, ctx, bufsize);
954         if (error)
955                 return error;
956         return 0;
957 }
958 
959 STATIC int
960 xfs_file_mmap(
961         struct file     *filp,
962         struct vm_area_struct *vma)
963 {
964         vma->vm_ops = &xfs_file_vm_ops;
965 
966         file_accessed(filp);
967         return 0;
968 }
969 
970 /*
971  * mmap()d file has taken write protection fault and is being made
972  * writable. We can set the page state up correctly for a writable
973  * page, which means we can do correct delalloc accounting (ENOSPC
974  * checking!) and unwritten extent mapping.
975  */
976 STATIC int
977 xfs_vm_page_mkwrite(
978         struct vm_area_struct   *vma,
979         struct vm_fault         *vmf)
980 {
981         return block_page_mkwrite(vma, vmf, xfs_get_blocks);
982 }
983 
984 /*
985  * This type is designed to indicate the type of offset we would like
986  * to search from page cache for xfs_seek_hole_data().
987  */
988 enum {
989         HOLE_OFF = 0,
990         DATA_OFF,
991 };
992 
993 /*
994  * Lookup the desired type of offset from the given page.
995  *
996  * On success, return true and the offset argument will point to the
997  * start of the region that was found.  Otherwise this function will
998  * return false and keep the offset argument unchanged.
999  */
1000 STATIC bool
1001 xfs_lookup_buffer_offset(
1002         struct page             *page,
1003         loff_t                  *offset,
1004         unsigned int            type)
1005 {
1006         loff_t                  lastoff = page_offset(page);
1007         bool                    found = false;
1008         struct buffer_head      *bh, *head;
1009 
1010         bh = head = page_buffers(page);
1011         do {
1012                 /*
1013                  * Unwritten extents that have data in the page
1014                  * cache covering them can be identified by the
1015                  * BH_Unwritten state flag.  Pages with multiple
1016                  * buffers might have a mix of holes, data and
1017                  * unwritten extents - any buffer with valid
1018                  * data in it should have BH_Uptodate flag set
1019                  * on it.
1020                  */
1021                 if (buffer_unwritten(bh) ||
1022                     buffer_uptodate(bh)) {
1023                         if (type == DATA_OFF)
1024                                 found = true;
1025                 } else {
1026                         if (type == HOLE_OFF)
1027                                 found = true;
1028                 }
1029 
1030                 if (found) {
1031                         *offset = lastoff;
1032                         break;
1033                 }
1034                 lastoff += bh->b_size;
1035         } while ((bh = bh->b_this_page) != head);
1036 
1037         return found;
1038 }
1039 
1040 /*
1041  * This routine is called to find out and return a data or hole offset
1042  * from the page cache for unwritten extents according to the desired
1043  * type for xfs_seek_hole_data().
1044  *
1045  * The argument offset is used to tell where we start to search from the
1046  * page cache.  Map is used to figure out the end points of the range to
1047  * lookup pages.
1048  *
1049  * Return true if the desired type of offset was found, and the argument
1050  * offset is filled with that address.  Otherwise, return false and keep
1051  * offset unchanged.
1052  */
1053 STATIC bool
1054 xfs_find_get_desired_pgoff(
1055         struct inode            *inode,
1056         struct xfs_bmbt_irec    *map,
1057         unsigned int            type,
1058         loff_t                  *offset)
1059 {
1060         struct xfs_inode        *ip = XFS_I(inode);
1061         struct xfs_mount        *mp = ip->i_mount;
1062         struct pagevec          pvec;
1063         pgoff_t                 index;
1064         pgoff_t                 end;
1065         loff_t                  endoff;
1066         loff_t                  startoff = *offset;
1067         loff_t                  lastoff = startoff;
1068         bool                    found = false;
1069 
1070         pagevec_init(&pvec, 0);
1071 
1072         index = startoff >> PAGE_CACHE_SHIFT;
1073         endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
1074         end = endoff >> PAGE_CACHE_SHIFT;
1075         do {
1076                 int             want;
1077                 unsigned        nr_pages;
1078                 unsigned int    i;
1079 
1080                 want = min_t(pgoff_t, end - index, PAGEVEC_SIZE);
1081                 nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
1082                                           want);
1083                 /*
1084                  * No page mapped into given range.  If we are searching holes
1085                  * and if this is the first time we got into the loop, it means
1086                  * that the given offset is landed in a hole, return it.
1087                  *
1088                  * If we have already stepped through some block buffers to find
1089                  * holes but they all contains data.  In this case, the last
1090                  * offset is already updated and pointed to the end of the last
1091                  * mapped page, if it does not reach the endpoint to search,
1092                  * that means there should be a hole between them.
1093                  */
1094                 if (nr_pages == 0) {
1095                         /* Data search found nothing */
1096                         if (type == DATA_OFF)
1097                                 break;
1098 
1099                         ASSERT(type == HOLE_OFF);
1100                         if (lastoff == startoff || lastoff < endoff) {
1101                                 found = true;
1102                                 *offset = lastoff;
1103                         }
1104                         break;
1105                 }
1106 
1107                 /*
1108                  * At lease we found one page.  If this is the first time we
1109                  * step into the loop, and if the first page index offset is
1110                  * greater than the given search offset, a hole was found.
1111                  */
1112                 if (type == HOLE_OFF && lastoff == startoff &&
1113                     lastoff < page_offset(pvec.pages[0])) {
1114                         found = true;
1115                         break;
1116                 }
1117 
1118                 for (i = 0; i < nr_pages; i++) {
1119                         struct page     *page = pvec.pages[i];
1120                         loff_t          b_offset;
1121 
1122                         /*
1123                          * At this point, the page may be truncated or
1124                          * invalidated (changing page->mapping to NULL),
1125                          * or even swizzled back from swapper_space to tmpfs
1126                          * file mapping. However, page->index will not change
1127                          * because we have a reference on the page.
1128                          *
1129                          * Searching done if the page index is out of range.
1130                          * If the current offset is not reaches the end of
1131                          * the specified search range, there should be a hole
1132                          * between them.
1133                          */
1134                         if (page->index > end) {
1135                                 if (type == HOLE_OFF && lastoff < endoff) {
1136                                         *offset = lastoff;
1137                                         found = true;
1138                                 }
1139                                 goto out;
1140                         }
1141 
1142                         lock_page(page);
1143                         /*
1144                          * Page truncated or invalidated(page->mapping == NULL).
1145                          * We can freely skip it and proceed to check the next
1146                          * page.
1147                          */
1148                         if (unlikely(page->mapping != inode->i_mapping)) {
1149                                 unlock_page(page);
1150                                 continue;
1151                         }
1152 
1153                         if (!page_has_buffers(page)) {
1154                                 unlock_page(page);
1155                                 continue;
1156                         }
1157 
1158                         found = xfs_lookup_buffer_offset(page, &b_offset, type);
1159                         if (found) {
1160                                 /*
1161                                  * The found offset may be less than the start
1162                                  * point to search if this is the first time to
1163                                  * come here.
1164                                  */
1165                                 *offset = max_t(loff_t, startoff, b_offset);
1166                                 unlock_page(page);
1167                                 goto out;
1168                         }
1169 
1170                         /*
1171                          * We either searching data but nothing was found, or
1172                          * searching hole but found a data buffer.  In either
1173                          * case, probably the next page contains the desired
1174                          * things, update the last offset to it so.
1175                          */
1176                         lastoff = page_offset(page) + PAGE_SIZE;
1177                         unlock_page(page);
1178                 }
1179 
1180                 /*
1181                  * The number of returned pages less than our desired, search
1182                  * done.  In this case, nothing was found for searching data,
1183                  * but we found a hole behind the last offset.
1184                  */
1185                 if (nr_pages < want) {
1186                         if (type == HOLE_OFF) {
1187                                 *offset = lastoff;
1188                                 found = true;
1189                         }
1190                         break;
1191                 }
1192 
1193                 index = pvec.pages[i - 1]->index + 1;
1194                 pagevec_release(&pvec);
1195         } while (index <= end);
1196 
1197 out:
1198         pagevec_release(&pvec);
1199         return found;
1200 }
1201 
1202 STATIC loff_t
1203 xfs_seek_hole_data(
1204         struct file             *file,
1205         loff_t                  start,
1206         int                     whence)
1207 {
1208         struct inode            *inode = file->f_mapping->host;
1209         struct xfs_inode        *ip = XFS_I(inode);
1210         struct xfs_mount        *mp = ip->i_mount;
1211         loff_t                  uninitialized_var(offset);
1212         xfs_fsize_t             isize;
1213         xfs_fileoff_t           fsbno;
1214         xfs_filblks_t           end;
1215         uint                    lock;
1216         int                     error;
1217 
1218         if (XFS_FORCED_SHUTDOWN(mp))
1219                 return -EIO;
1220 
1221         lock = xfs_ilock_data_map_shared(ip);
1222 
1223         isize = i_size_read(inode);
1224         if (start >= isize) {
1225                 error = -ENXIO;
1226                 goto out_unlock;
1227         }
1228 
1229         /*
1230          * Try to read extents from the first block indicated
1231          * by fsbno to the end block of the file.
1232          */
1233         fsbno = XFS_B_TO_FSBT(mp, start);
1234         end = XFS_B_TO_FSB(mp, isize);
1235 
1236         for (;;) {
1237                 struct xfs_bmbt_irec    map[2];
1238                 int                     nmap = 2;
1239                 unsigned int            i;
1240 
1241                 error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap,
1242                                        XFS_BMAPI_ENTIRE);
1243                 if (error)
1244                         goto out_unlock;
1245 
1246                 /* No extents at given offset, must be beyond EOF */
1247                 if (nmap == 0) {
1248                         error = -ENXIO;
1249                         goto out_unlock;
1250                 }
1251 
1252                 for (i = 0; i < nmap; i++) {
1253                         offset = max_t(loff_t, start,
1254                                        XFS_FSB_TO_B(mp, map[i].br_startoff));
1255 
1256                         /* Landed in the hole we wanted? */
1257                         if (whence == SEEK_HOLE &&
1258                             map[i].br_startblock == HOLESTARTBLOCK)
1259                                 goto out;
1260 
1261                         /* Landed in the data extent we wanted? */
1262                         if (whence == SEEK_DATA &&
1263                             (map[i].br_startblock == DELAYSTARTBLOCK ||
1264                              (map[i].br_state == XFS_EXT_NORM &&
1265                               !isnullstartblock(map[i].br_startblock))))
1266                                 goto out;
1267 
1268                         /*
1269                          * Landed in an unwritten extent, try to search
1270                          * for hole or data from page cache.
1271                          */
1272                         if (map[i].br_state == XFS_EXT_UNWRITTEN) {
1273                                 if (xfs_find_get_desired_pgoff(inode, &map[i],
1274                                       whence == SEEK_HOLE ? HOLE_OFF : DATA_OFF,
1275                                                         &offset))
1276                                         goto out;
1277                         }
1278                 }
1279 
1280                 /*
1281                  * We only received one extent out of the two requested. This
1282                  * means we've hit EOF and didn't find what we are looking for.
1283                  */
1284                 if (nmap == 1) {
1285                         /*
1286                          * If we were looking for a hole, set offset to
1287                          * the end of the file (i.e., there is an implicit
1288                          * hole at the end of any file).
1289                          */
1290                         if (whence == SEEK_HOLE) {
1291                                 offset = isize;
1292                                 break;
1293                         }
1294                         /*
1295                          * If we were looking for data, it's nowhere to be found
1296                          */
1297                         ASSERT(whence == SEEK_DATA);
1298                         error = -ENXIO;
1299                         goto out_unlock;
1300                 }
1301 
1302                 ASSERT(i > 1);
1303 
1304                 /*
1305                  * Nothing was found, proceed to the next round of search
1306                  * if the next reading offset is not at or beyond EOF.
1307                  */
1308                 fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount;
1309                 start = XFS_FSB_TO_B(mp, fsbno);
1310                 if (start >= isize) {
1311                         if (whence == SEEK_HOLE) {
1312                                 offset = isize;
1313                                 break;
1314                         }
1315                         ASSERT(whence == SEEK_DATA);
1316                         error = -ENXIO;
1317                         goto out_unlock;
1318                 }
1319         }
1320 
1321 out:
1322         /*
1323          * If at this point we have found the hole we wanted, the returned
1324          * offset may be bigger than the file size as it may be aligned to
1325          * page boundary for unwritten extents.  We need to deal with this
1326          * situation in particular.
1327          */
1328         if (whence == SEEK_HOLE)
1329                 offset = min_t(loff_t, offset, isize);
1330         offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1331 
1332 out_unlock:
1333         xfs_iunlock(ip, lock);
1334 
1335         if (error)
1336                 return error;
1337         return offset;
1338 }
1339 
1340 STATIC loff_t
1341 xfs_file_llseek(
1342         struct file     *file,
1343         loff_t          offset,
1344         int             whence)
1345 {
1346         switch (whence) {
1347         case SEEK_END:
1348         case SEEK_CUR:
1349         case SEEK_SET:
1350                 return generic_file_llseek(file, offset, whence);
1351         case SEEK_HOLE:
1352         case SEEK_DATA:
1353                 return xfs_seek_hole_data(file, offset, whence);
1354         default:
1355                 return -EINVAL;
1356         }
1357 }
1358 
1359 const struct file_operations xfs_file_operations = {
1360         .llseek         = xfs_file_llseek,
1361         .read           = new_sync_read,
1362         .write          = new_sync_write,
1363         .read_iter      = xfs_file_read_iter,
1364         .write_iter     = xfs_file_write_iter,
1365         .splice_read    = xfs_file_splice_read,
1366         .splice_write   = iter_file_splice_write,
1367         .unlocked_ioctl = xfs_file_ioctl,
1368 #ifdef CONFIG_COMPAT
1369         .compat_ioctl   = xfs_file_compat_ioctl,
1370 #endif
1371         .mmap           = xfs_file_mmap,
1372         .open           = xfs_file_open,
1373         .release        = xfs_file_release,
1374         .fsync          = xfs_file_fsync,
1375         .fallocate      = xfs_file_fallocate,
1376 };
1377 
1378 const struct file_operations xfs_dir_file_operations = {
1379         .open           = xfs_dir_open,
1380         .read           = generic_read_dir,
1381         .iterate        = xfs_file_readdir,
1382         .llseek         = generic_file_llseek,
1383         .unlocked_ioctl = xfs_file_ioctl,
1384 #ifdef CONFIG_COMPAT
1385         .compat_ioctl   = xfs_file_compat_ioctl,
1386 #endif
1387         .fsync          = xfs_dir_fsync,
1388 };
1389 
1390 static const struct vm_operations_struct xfs_file_vm_ops = {
1391         .fault          = filemap_fault,
1392         .map_pages      = filemap_map_pages,
1393         .page_mkwrite   = xfs_vm_page_mkwrite,
1394         .remap_pages    = generic_file_remap_pages,
1395 };
1396 

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