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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Nathan Scott7b718762005-11-02 14:58:39 +11002 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
Nathan Scott7b718762005-11-02 14:58:39 +11005 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * published by the Free Software Foundation.
8 *
Nathan Scott7b718762005-11-02 14:58:39 +11009 * 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.
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 *
Nathan Scott7b718762005-11-02 14:58:39 +110014 * 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include "xfs.h"
Christoph Hellwigdda35b82010-02-15 09:44:46 +000019#include "xfs_fs.h"
Dave Chinner70a9883c2013-10-23 10:36:05 +110020#include "xfs_shared.h"
Dave Chinnera4fbe6a2013-10-23 10:51:50 +110021#include "xfs_format.h"
Dave Chinner239880e2013-10-23 10:50:10 +110022#include "xfs_log_format.h"
23#include "xfs_trans_resv.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include "xfs_mount.h"
Dave Chinner57062782013-10-15 09:17:51 +110025#include "xfs_da_format.h"
26#include "xfs_da_btree.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include "xfs_inode.h"
Dave Chinner239880e2013-10-23 10:50:10 +110028#include "xfs_trans.h"
Christoph Hellwigfd3200b2010-02-15 09:44:48 +000029#include "xfs_inode_item.h"
Christoph Hellwigdda35b82010-02-15 09:44:46 +000030#include "xfs_bmap.h"
Dave Chinnerc24b5df2013-08-12 20:49:45 +100031#include "xfs_bmap_util.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include "xfs_error.h"
Dave Chinner2b9ab5a2013-08-12 20:49:37 +100033#include "xfs_dir2.h"
Dave Chinnerc24b5df2013-08-12 20:49:45 +100034#include "xfs_dir2_priv.h"
Christoph Hellwigddcd8562008-12-03 07:55:34 -050035#include "xfs_ioctl.h"
Christoph Hellwigdda35b82010-02-15 09:44:46 +000036#include "xfs_trace.h"
Dave Chinner239880e2013-10-23 10:50:10 +110037#include "xfs_log.h"
Brian Fosterdc06f3982014-07-24 19:49:28 +100038#include "xfs_icache.h"
Christoph Hellwig781355c2015-02-16 11:59:50 +110039#include "xfs_pnfs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070040
41#include <linux/dcache.h>
Christoph Hellwig2fe17c12011-01-14 13:07:43 +010042#include <linux/falloc.h>
Jeff Liud126d432012-08-21 17:11:57 +080043#include <linux/pagevec.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +040045static const struct vm_operations_struct xfs_file_vm_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
Christoph Hellwigdda35b82010-02-15 09:44:46 +000047/*
Dave Chinner487f84f2011-01-12 11:37:10 +110048 * Locking primitives for read and write IO paths to ensure we consistently use
49 * and order the inode->i_mutex, ip->i_lock and ip->i_iolock.
50 */
51static inline void
52xfs_rw_ilock(
53 struct xfs_inode *ip,
54 int type)
55{
56 if (type & XFS_IOLOCK_EXCL)
57 mutex_lock(&VFS_I(ip)->i_mutex);
58 xfs_ilock(ip, type);
59}
60
61static inline void
62xfs_rw_iunlock(
63 struct xfs_inode *ip,
64 int type)
65{
66 xfs_iunlock(ip, type);
67 if (type & XFS_IOLOCK_EXCL)
68 mutex_unlock(&VFS_I(ip)->i_mutex);
69}
70
71static inline void
72xfs_rw_ilock_demote(
73 struct xfs_inode *ip,
74 int type)
75{
76 xfs_ilock_demote(ip, type);
77 if (type & XFS_IOLOCK_EXCL)
78 mutex_unlock(&VFS_I(ip)->i_mutex);
79}
80
81/*
Christoph Hellwigdda35b82010-02-15 09:44:46 +000082 * xfs_iozero
83 *
84 * xfs_iozero clears the specified range of buffer supplied,
85 * and marks all the affected blocks as valid and modified. If
86 * an affected block is not allocated, it will be allocated. If
87 * an affected block is not completely overwritten, and is not
88 * valid before the operation, it will be read from disk before
89 * being partially zeroed.
90 */
Dave Chinneref9d8732012-11-29 15:26:33 +110091int
Christoph Hellwigdda35b82010-02-15 09:44:46 +000092xfs_iozero(
93 struct xfs_inode *ip, /* inode */
94 loff_t pos, /* offset in file */
95 size_t count) /* size of data to zero */
96{
97 struct page *page;
98 struct address_space *mapping;
99 int status;
100
101 mapping = VFS_I(ip)->i_mapping;
102 do {
103 unsigned offset, bytes;
104 void *fsdata;
105
106 offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
107 bytes = PAGE_CACHE_SIZE - offset;
108 if (bytes > count)
109 bytes = count;
110
111 status = pagecache_write_begin(NULL, mapping, pos, bytes,
112 AOP_FLAG_UNINTERRUPTIBLE,
113 &page, &fsdata);
114 if (status)
115 break;
116
117 zero_user(page, offset, bytes);
118
119 status = pagecache_write_end(NULL, mapping, pos, bytes, bytes,
120 page, fsdata);
121 WARN_ON(status <= 0); /* can't return less than zero! */
122 pos += bytes;
123 count -= bytes;
124 status = 0;
125 } while (count);
126
127 return (-status);
128}
129
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100130int
131xfs_update_prealloc_flags(
132 struct xfs_inode *ip,
133 enum xfs_prealloc_flags flags)
134{
135 struct xfs_trans *tp;
136 int error;
137
138 tp = xfs_trans_alloc(ip->i_mount, XFS_TRANS_WRITEID);
139 error = xfs_trans_reserve(tp, &M_RES(ip->i_mount)->tr_writeid, 0, 0);
140 if (error) {
141 xfs_trans_cancel(tp, 0);
142 return error;
143 }
144
145 xfs_ilock(ip, XFS_ILOCK_EXCL);
146 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
147
148 if (!(flags & XFS_PREALLOC_INVISIBLE)) {
149 ip->i_d.di_mode &= ~S_ISUID;
150 if (ip->i_d.di_mode & S_IXGRP)
151 ip->i_d.di_mode &= ~S_ISGID;
152 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
153 }
154
155 if (flags & XFS_PREALLOC_SET)
156 ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
157 if (flags & XFS_PREALLOC_CLEAR)
158 ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC;
159
160 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
161 if (flags & XFS_PREALLOC_SYNC)
162 xfs_trans_set_sync(tp);
163 return xfs_trans_commit(tp, 0);
164}
165
Christoph Hellwig1da2f2d2011-10-02 14:25:16 +0000166/*
167 * Fsync operations on directories are much simpler than on regular files,
168 * as there is no file data to flush, and thus also no need for explicit
169 * cache flush operations, and there are no non-transaction metadata updates
170 * on directories either.
171 */
172STATIC int
173xfs_dir_fsync(
174 struct file *file,
175 loff_t start,
176 loff_t end,
177 int datasync)
178{
179 struct xfs_inode *ip = XFS_I(file->f_mapping->host);
180 struct xfs_mount *mp = ip->i_mount;
181 xfs_lsn_t lsn = 0;
182
183 trace_xfs_dir_fsync(ip);
184
185 xfs_ilock(ip, XFS_ILOCK_SHARED);
186 if (xfs_ipincount(ip))
187 lsn = ip->i_itemp->ili_last_lsn;
188 xfs_iunlock(ip, XFS_ILOCK_SHARED);
189
190 if (!lsn)
191 return 0;
Dave Chinner24513372014-06-25 14:58:08 +1000192 return _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, NULL);
Christoph Hellwig1da2f2d2011-10-02 14:25:16 +0000193}
194
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000195STATIC int
196xfs_file_fsync(
197 struct file *file,
Josef Bacik02c24a82011-07-16 20:44:56 -0400198 loff_t start,
199 loff_t end,
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000200 int datasync)
201{
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200202 struct inode *inode = file->f_mapping->host;
203 struct xfs_inode *ip = XFS_I(inode);
Christoph Hellwiga27a2632011-06-16 12:02:23 +0000204 struct xfs_mount *mp = ip->i_mount;
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000205 int error = 0;
206 int log_flushed = 0;
Christoph Hellwigb1037052011-09-19 14:55:51 +0000207 xfs_lsn_t lsn = 0;
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000208
Christoph Hellwigcca28fb2010-06-24 11:57:09 +1000209 trace_xfs_file_fsync(ip);
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000210
Josef Bacik02c24a82011-07-16 20:44:56 -0400211 error = filemap_write_and_wait_range(inode->i_mapping, start, end);
212 if (error)
213 return error;
214
Christoph Hellwiga27a2632011-06-16 12:02:23 +0000215 if (XFS_FORCED_SHUTDOWN(mp))
Eric Sandeenb474c7a2014-06-22 15:04:54 +1000216 return -EIO;
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000217
218 xfs_iflags_clear(ip, XFS_ITRUNCATED);
219
Christoph Hellwiga27a2632011-06-16 12:02:23 +0000220 if (mp->m_flags & XFS_MOUNT_BARRIER) {
221 /*
222 * If we have an RT and/or log subvolume we need to make sure
223 * to flush the write cache the device used for file data
224 * first. This is to ensure newly written file data make
225 * it to disk before logging the new inode size in case of
226 * an extending write.
227 */
228 if (XFS_IS_REALTIME_INODE(ip))
229 xfs_blkdev_issue_flush(mp->m_rtdev_targp);
230 else if (mp->m_logdev_targp != mp->m_ddev_targp)
231 xfs_blkdev_issue_flush(mp->m_ddev_targp);
232 }
233
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000234 /*
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000235 * All metadata updates are logged, which means that we just have
236 * to flush the log up to the latest LSN that touched the inode.
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000237 */
238 xfs_ilock(ip, XFS_ILOCK_SHARED);
Christoph Hellwig8f639dd2012-02-29 09:53:55 +0000239 if (xfs_ipincount(ip)) {
240 if (!datasync ||
241 (ip->i_itemp->ili_fields & ~XFS_ILOG_TIMESTAMP))
242 lsn = ip->i_itemp->ili_last_lsn;
243 }
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000244 xfs_iunlock(ip, XFS_ILOCK_SHARED);
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000245
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000246 if (lsn)
Christoph Hellwigb1037052011-09-19 14:55:51 +0000247 error = _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, &log_flushed);
248
Christoph Hellwiga27a2632011-06-16 12:02:23 +0000249 /*
250 * If we only have a single device, and the log force about was
251 * a no-op we might have to flush the data device cache here.
252 * This can only happen for fdatasync/O_DSYNC if we were overwriting
253 * an already allocated file and thus do not have any metadata to
254 * commit.
255 */
256 if ((mp->m_flags & XFS_MOUNT_BARRIER) &&
257 mp->m_logdev_targp == mp->m_ddev_targp &&
258 !XFS_IS_REALTIME_INODE(ip) &&
259 !log_flushed)
260 xfs_blkdev_issue_flush(mp->m_ddev_targp);
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000261
Dave Chinner24513372014-06-25 14:58:08 +1000262 return error;
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000263}
264
Christoph Hellwig00258e32010-02-15 09:44:47 +0000265STATIC ssize_t
Al Virob4f5d2c2014-04-02 14:37:59 -0400266xfs_file_read_iter(
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000267 struct kiocb *iocb,
Al Virob4f5d2c2014-04-02 14:37:59 -0400268 struct iov_iter *to)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000269{
270 struct file *file = iocb->ki_filp;
271 struct inode *inode = file->f_mapping->host;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000272 struct xfs_inode *ip = XFS_I(inode);
273 struct xfs_mount *mp = ip->i_mount;
Al Virob4f5d2c2014-04-02 14:37:59 -0400274 size_t size = iov_iter_count(to);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000275 ssize_t ret = 0;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000276 int ioflags = 0;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000277 xfs_fsize_t n;
Al Virob4f5d2c2014-04-02 14:37:59 -0400278 loff_t pos = iocb->ki_pos;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000279
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000280 XFS_STATS_INC(xs_read_calls);
281
Al Viro2ba48ce2015-04-09 13:52:01 -0400282 if (unlikely(iocb->ki_flags & IOCB_DIRECT))
Dave Chinnerb92cc59f62014-08-04 13:28:20 +1000283 ioflags |= XFS_IO_ISDIRECT;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000284 if (file->f_mode & FMODE_NOCMTIME)
Dave Chinnerb92cc59f62014-08-04 13:28:20 +1000285 ioflags |= XFS_IO_INVIS;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000286
Dave Chinner6b698ed2015-06-04 09:18:53 +1000287 if ((ioflags & XFS_IO_ISDIRECT) && !IS_DAX(inode)) {
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000288 xfs_buftarg_t *target =
289 XFS_IS_REALTIME_INODE(ip) ?
290 mp->m_rtdev_targp : mp->m_ddev_targp;
Eric Sandeen7c71ee72014-01-21 16:46:23 -0600291 /* DIO must be aligned to device logical sector size */
292 if ((pos | size) & target->bt_logical_sectormask) {
Dave Chinnerfb595812012-11-12 22:53:57 +1100293 if (pos == i_size_read(inode))
Christoph Hellwig00258e32010-02-15 09:44:47 +0000294 return 0;
Eric Sandeenb474c7a2014-06-22 15:04:54 +1000295 return -EINVAL;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000296 }
297 }
298
Dave Chinnerfb595812012-11-12 22:53:57 +1100299 n = mp->m_super->s_maxbytes - pos;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000300 if (n <= 0 || size == 0)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000301 return 0;
302
303 if (n < size)
304 size = n;
305
306 if (XFS_FORCED_SHUTDOWN(mp))
307 return -EIO;
308
Dave Chinner0c38a252011-08-25 07:17:01 +0000309 /*
310 * Locking is a bit tricky here. If we take an exclusive lock
311 * for direct IO, we effectively serialise all new concurrent
312 * read IO to this file and block it behind IO that is currently in
313 * progress because IO in progress holds the IO lock shared. We only
314 * need to hold the lock exclusive to blow away the page cache, so
315 * only take lock exclusively if the page cache needs invalidation.
316 * This allows the normal direct IO case of no page cache pages to
317 * proceeed concurrently without serialisation.
318 */
319 xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
Dave Chinnerb92cc59f62014-08-04 13:28:20 +1000320 if ((ioflags & XFS_IO_ISDIRECT) && inode->i_mapping->nrpages) {
Dave Chinner0c38a252011-08-25 07:17:01 +0000321 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
Dave Chinner487f84f2011-01-12 11:37:10 +1100322 xfs_rw_ilock(ip, XFS_IOLOCK_EXCL);
323
Christoph Hellwig00258e32010-02-15 09:44:47 +0000324 if (inode->i_mapping->nrpages) {
Dave Chinner8ff1e672014-05-15 09:21:37 +1000325 ret = filemap_write_and_wait_range(
Dave Chinnerfb595812012-11-12 22:53:57 +1100326 VFS_I(ip)->i_mapping,
Dave Chinner7d4ea3c2014-09-02 12:12:53 +1000327 pos, pos + size - 1);
Dave Chinner487f84f2011-01-12 11:37:10 +1100328 if (ret) {
329 xfs_rw_iunlock(ip, XFS_IOLOCK_EXCL);
330 return ret;
331 }
Chris Mason85e584d2014-09-02 12:12:52 +1000332
333 /*
334 * Invalidate whole pages. This can return an error if
335 * we fail to invalidate a page, but this should never
336 * happen on XFS. Warn if it does fail.
337 */
338 ret = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
Dave Chinner7d4ea3c2014-09-02 12:12:53 +1000339 pos >> PAGE_CACHE_SHIFT,
340 (pos + size - 1) >> PAGE_CACHE_SHIFT);
Chris Mason85e584d2014-09-02 12:12:52 +1000341 WARN_ON_ONCE(ret);
342 ret = 0;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000343 }
Dave Chinner487f84f2011-01-12 11:37:10 +1100344 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
Dave Chinner0c38a252011-08-25 07:17:01 +0000345 }
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000346
Dave Chinnerfb595812012-11-12 22:53:57 +1100347 trace_xfs_file_read(ip, size, pos, ioflags);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000348
Al Virob4f5d2c2014-04-02 14:37:59 -0400349 ret = generic_file_read_iter(iocb, to);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000350 if (ret > 0)
351 XFS_STATS_ADD(xs_read_bytes, ret);
352
Dave Chinner487f84f2011-01-12 11:37:10 +1100353 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000354 return ret;
355}
356
Christoph Hellwig00258e32010-02-15 09:44:47 +0000357STATIC ssize_t
358xfs_file_splice_read(
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000359 struct file *infilp,
360 loff_t *ppos,
361 struct pipe_inode_info *pipe,
362 size_t count,
Christoph Hellwig00258e32010-02-15 09:44:47 +0000363 unsigned int flags)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000364{
Christoph Hellwig00258e32010-02-15 09:44:47 +0000365 struct xfs_inode *ip = XFS_I(infilp->f_mapping->host);
Christoph Hellwig00258e32010-02-15 09:44:47 +0000366 int ioflags = 0;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000367 ssize_t ret;
368
369 XFS_STATS_INC(xs_read_calls);
Christoph Hellwig00258e32010-02-15 09:44:47 +0000370
371 if (infilp->f_mode & FMODE_NOCMTIME)
Dave Chinnerb92cc59f62014-08-04 13:28:20 +1000372 ioflags |= XFS_IO_INVIS;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000373
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000374 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
375 return -EIO;
376
Dave Chinner487f84f2011-01-12 11:37:10 +1100377 xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000378
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000379 trace_xfs_file_splice_read(ip, count, *ppos, ioflags);
380
Dave Chinner6b698ed2015-06-04 09:18:53 +1000381 /* for dax, we need to avoid the page cache */
382 if (IS_DAX(VFS_I(ip)))
383 ret = default_file_splice_read(infilp, ppos, pipe, count, flags);
384 else
385 ret = generic_file_splice_read(infilp, ppos, pipe, count, flags);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000386 if (ret > 0)
387 XFS_STATS_ADD(xs_read_bytes, ret);
388
Dave Chinner487f84f2011-01-12 11:37:10 +1100389 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000390 return ret;
391}
392
Dave Chinner4c5cfd12011-01-11 10:14:16 +1100393/*
Christoph Hellwig193aec12012-03-27 10:34:49 -0400394 * This routine is called to handle zeroing any space in the last block of the
395 * file that is beyond the EOF. We do this since the size is being increased
396 * without writing anything to that block and we don't want to read the
397 * garbage on the disk.
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000398 */
399STATIC int /* error (positive) */
400xfs_zero_last_block(
Christoph Hellwig193aec12012-03-27 10:34:49 -0400401 struct xfs_inode *ip,
402 xfs_fsize_t offset,
Dave Chinner5885ebd2015-02-23 22:37:08 +1100403 xfs_fsize_t isize,
404 bool *did_zeroing)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000405{
Christoph Hellwig193aec12012-03-27 10:34:49 -0400406 struct xfs_mount *mp = ip->i_mount;
407 xfs_fileoff_t last_fsb = XFS_B_TO_FSBT(mp, isize);
408 int zero_offset = XFS_B_FSB_OFFSET(mp, isize);
409 int zero_len;
410 int nimaps = 1;
411 int error = 0;
412 struct xfs_bmbt_irec imap;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000413
Christoph Hellwig193aec12012-03-27 10:34:49 -0400414 xfs_ilock(ip, XFS_ILOCK_EXCL);
Dave Chinner5c8ed202011-09-18 20:40:45 +0000415 error = xfs_bmapi_read(ip, last_fsb, 1, &imap, &nimaps, 0);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400416 xfs_iunlock(ip, XFS_ILOCK_EXCL);
Dave Chinner5c8ed202011-09-18 20:40:45 +0000417 if (error)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000418 return error;
Christoph Hellwig193aec12012-03-27 10:34:49 -0400419
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000420 ASSERT(nimaps > 0);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400421
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000422 /*
423 * If the block underlying isize is just a hole, then there
424 * is nothing to zero.
425 */
Christoph Hellwig193aec12012-03-27 10:34:49 -0400426 if (imap.br_startblock == HOLESTARTBLOCK)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000427 return 0;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000428
429 zero_len = mp->m_sb.sb_blocksize - zero_offset;
430 if (isize + zero_len > offset)
431 zero_len = offset - isize;
Dave Chinner5885ebd2015-02-23 22:37:08 +1100432 *did_zeroing = true;
Christoph Hellwig193aec12012-03-27 10:34:49 -0400433 return xfs_iozero(ip, isize, zero_len);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000434}
435
436/*
Christoph Hellwig193aec12012-03-27 10:34:49 -0400437 * Zero any on disk space between the current EOF and the new, larger EOF.
438 *
439 * This handles the normal case of zeroing the remainder of the last block in
440 * the file and the unusual case of zeroing blocks out beyond the size of the
441 * file. This second case only happens with fixed size extents and when the
442 * system crashes before the inode size was updated but after blocks were
443 * allocated.
444 *
445 * Expects the iolock to be held exclusive, and will take the ilock internally.
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000446 */
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000447int /* error (positive) */
448xfs_zero_eof(
Christoph Hellwig193aec12012-03-27 10:34:49 -0400449 struct xfs_inode *ip,
450 xfs_off_t offset, /* starting I/O offset */
Dave Chinner5885ebd2015-02-23 22:37:08 +1100451 xfs_fsize_t isize, /* current inode size */
452 bool *did_zeroing)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000453{
Christoph Hellwig193aec12012-03-27 10:34:49 -0400454 struct xfs_mount *mp = ip->i_mount;
455 xfs_fileoff_t start_zero_fsb;
456 xfs_fileoff_t end_zero_fsb;
457 xfs_fileoff_t zero_count_fsb;
458 xfs_fileoff_t last_fsb;
459 xfs_fileoff_t zero_off;
460 xfs_fsize_t zero_len;
461 int nimaps;
462 int error = 0;
463 struct xfs_bmbt_irec imap;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000464
Christoph Hellwig193aec12012-03-27 10:34:49 -0400465 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000466 ASSERT(offset > isize);
467
468 /*
469 * First handle zeroing the block on which isize resides.
Christoph Hellwig193aec12012-03-27 10:34:49 -0400470 *
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000471 * We only zero a part of that block so it is handled specially.
472 */
Christoph Hellwig193aec12012-03-27 10:34:49 -0400473 if (XFS_B_FSB_OFFSET(mp, isize) != 0) {
Dave Chinner5885ebd2015-02-23 22:37:08 +1100474 error = xfs_zero_last_block(ip, offset, isize, did_zeroing);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400475 if (error)
476 return error;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000477 }
478
479 /*
Christoph Hellwig193aec12012-03-27 10:34:49 -0400480 * Calculate the range between the new size and the old where blocks
481 * needing to be zeroed may exist.
482 *
483 * To get the block where the last byte in the file currently resides,
484 * we need to subtract one from the size and truncate back to a block
485 * boundary. We subtract 1 in case the size is exactly on a block
486 * boundary.
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000487 */
488 last_fsb = isize ? XFS_B_TO_FSBT(mp, isize - 1) : (xfs_fileoff_t)-1;
489 start_zero_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)isize);
490 end_zero_fsb = XFS_B_TO_FSBT(mp, offset - 1);
491 ASSERT((xfs_sfiloff_t)last_fsb < (xfs_sfiloff_t)start_zero_fsb);
492 if (last_fsb == end_zero_fsb) {
493 /*
494 * The size was only incremented on its last block.
495 * We took care of that above, so just return.
496 */
497 return 0;
498 }
499
500 ASSERT(start_zero_fsb <= end_zero_fsb);
501 while (start_zero_fsb <= end_zero_fsb) {
502 nimaps = 1;
503 zero_count_fsb = end_zero_fsb - start_zero_fsb + 1;
Christoph Hellwig193aec12012-03-27 10:34:49 -0400504
505 xfs_ilock(ip, XFS_ILOCK_EXCL);
Dave Chinner5c8ed202011-09-18 20:40:45 +0000506 error = xfs_bmapi_read(ip, start_zero_fsb, zero_count_fsb,
507 &imap, &nimaps, 0);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400508 xfs_iunlock(ip, XFS_ILOCK_EXCL);
509 if (error)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000510 return error;
Christoph Hellwig193aec12012-03-27 10:34:49 -0400511
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000512 ASSERT(nimaps > 0);
513
514 if (imap.br_state == XFS_EXT_UNWRITTEN ||
515 imap.br_startblock == HOLESTARTBLOCK) {
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000516 start_zero_fsb = imap.br_startoff + imap.br_blockcount;
517 ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
518 continue;
519 }
520
521 /*
522 * There are blocks we need to zero.
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000523 */
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000524 zero_off = XFS_FSB_TO_B(mp, start_zero_fsb);
525 zero_len = XFS_FSB_TO_B(mp, imap.br_blockcount);
526
527 if ((zero_off + zero_len) > offset)
528 zero_len = offset - zero_off;
529
530 error = xfs_iozero(ip, zero_off, zero_len);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400531 if (error)
532 return error;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000533
Dave Chinner5885ebd2015-02-23 22:37:08 +1100534 *did_zeroing = true;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000535 start_zero_fsb = imap.br_startoff + imap.br_blockcount;
536 ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000537 }
538
539 return 0;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000540}
541
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100542/*
Dave Chinner4d8d1582011-01-11 10:23:42 +1100543 * Common pre-write limit and setup checks.
544 *
Christoph Hellwig5bf1f262011-12-18 20:00:13 +0000545 * Called with the iolocked held either shared and exclusive according to
546 * @iolock, and returns with it held. Might upgrade the iolock to exclusive
547 * if called for a direct write beyond i_size.
Dave Chinner4d8d1582011-01-11 10:23:42 +1100548 */
549STATIC ssize_t
550xfs_file_aio_write_checks(
Al Viro99733fa2015-04-07 14:25:18 -0400551 struct kiocb *iocb,
552 struct iov_iter *from,
Dave Chinner4d8d1582011-01-11 10:23:42 +1100553 int *iolock)
554{
Al Viro99733fa2015-04-07 14:25:18 -0400555 struct file *file = iocb->ki_filp;
Dave Chinner4d8d1582011-01-11 10:23:42 +1100556 struct inode *inode = file->f_mapping->host;
557 struct xfs_inode *ip = XFS_I(inode);
Al Viro3309dd02015-04-09 12:55:47 -0400558 ssize_t error = 0;
Al Viro99733fa2015-04-07 14:25:18 -0400559 size_t count = iov_iter_count(from);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100560
Dave Chinner7271d242011-08-25 07:17:02 +0000561restart:
Al Viro3309dd02015-04-09 12:55:47 -0400562 error = generic_write_checks(iocb, from);
563 if (error <= 0)
Dave Chinner4d8d1582011-01-11 10:23:42 +1100564 return error;
Dave Chinner4d8d1582011-01-11 10:23:42 +1100565
Christoph Hellwig21c3ea12015-04-13 11:38:29 +1000566 error = xfs_break_layouts(inode, iolock, true);
Christoph Hellwig781355c2015-02-16 11:59:50 +1100567 if (error)
568 return error;
569
Dave Chinner4d8d1582011-01-11 10:23:42 +1100570 /*
571 * If the offset is beyond the size of the file, we need to zero any
572 * blocks that fall between the existing EOF and the start of this
Christoph Hellwig2813d682011-12-18 20:00:12 +0000573 * write. If zeroing is needed and we are currently holding the
Christoph Hellwig467f7892012-03-27 10:34:47 -0400574 * iolock shared, we need to update it to exclusive which implies
575 * having to redo all checks before.
Dave Chinnerb9d59842015-04-16 22:03:07 +1000576 *
577 * We need to serialise against EOF updates that occur in IO
578 * completions here. We want to make sure that nobody is changing the
579 * size while we do this check until we have placed an IO barrier (i.e.
580 * hold the XFS_IOLOCK_EXCL) that prevents new IO from being dispatched.
581 * The spinlock effectively forms a memory barrier once we have the
582 * XFS_IOLOCK_EXCL so we are guaranteed to see the latest EOF value
583 * and hence be able to correctly determine if we need to run zeroing.
Dave Chinner4d8d1582011-01-11 10:23:42 +1100584 */
Dave Chinnerb9d59842015-04-16 22:03:07 +1000585 spin_lock(&ip->i_flags_lock);
Al Viro99733fa2015-04-07 14:25:18 -0400586 if (iocb->ki_pos > i_size_read(inode)) {
Dave Chinner5885ebd2015-02-23 22:37:08 +1100587 bool zero = false;
588
Dave Chinnerb9d59842015-04-16 22:03:07 +1000589 spin_unlock(&ip->i_flags_lock);
Dave Chinner7271d242011-08-25 07:17:02 +0000590 if (*iolock == XFS_IOLOCK_SHARED) {
Christoph Hellwig467f7892012-03-27 10:34:47 -0400591 xfs_rw_iunlock(ip, *iolock);
Dave Chinner7271d242011-08-25 07:17:02 +0000592 *iolock = XFS_IOLOCK_EXCL;
Christoph Hellwig467f7892012-03-27 10:34:47 -0400593 xfs_rw_ilock(ip, *iolock);
Al Viro3309dd02015-04-09 12:55:47 -0400594 iov_iter_reexpand(from, count);
Dave Chinner40c63fb2015-04-16 22:03:17 +1000595
596 /*
597 * We now have an IO submission barrier in place, but
598 * AIO can do EOF updates during IO completion and hence
599 * we now need to wait for all of them to drain. Non-AIO
600 * DIO will have drained before we are given the
601 * XFS_IOLOCK_EXCL, and so for most cases this wait is a
602 * no-op.
603 */
604 inode_dio_wait(inode);
Dave Chinner7271d242011-08-25 07:17:02 +0000605 goto restart;
606 }
Al Viro99733fa2015-04-07 14:25:18 -0400607 error = xfs_zero_eof(ip, iocb->ki_pos, i_size_read(inode), &zero);
Christoph Hellwig467f7892012-03-27 10:34:47 -0400608 if (error)
609 return error;
Dave Chinnerb9d59842015-04-16 22:03:07 +1000610 } else
611 spin_unlock(&ip->i_flags_lock);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100612
613 /*
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000614 * Updating the timestamps will grab the ilock again from
615 * xfs_fs_dirty_inode, so we have to call it after dropping the
616 * lock above. Eventually we should look into a way to avoid
617 * the pointless lock roundtrip.
618 */
Josef Bacikc3b2da32012-03-26 09:59:21 -0400619 if (likely(!(file->f_mode & FMODE_NOCMTIME))) {
620 error = file_update_time(file);
621 if (error)
622 return error;
623 }
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000624
625 /*
Dave Chinner4d8d1582011-01-11 10:23:42 +1100626 * If we're writing the file then make sure to clear the setuid and
627 * setgid bits if the process is not being run by root. This keeps
628 * people from modifying setuid and setgid binaries.
629 */
630 return file_remove_suid(file);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100631}
632
633/*
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100634 * xfs_file_dio_aio_write - handle direct IO writes
635 *
636 * Lock the inode appropriately to prepare for and issue a direct IO write.
Dave Chinnereda77982011-01-11 10:22:40 +1100637 * By separating it from the buffered write path we remove all the tricky to
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100638 * follow locking changes and looping.
639 *
Dave Chinnereda77982011-01-11 10:22:40 +1100640 * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
641 * until we're sure the bytes at the new EOF have been zeroed and/or the cached
642 * pages are flushed out.
643 *
644 * In most cases the direct IO writes will be done holding IOLOCK_SHARED
645 * allowing them to be done in parallel with reads and other direct IO writes.
646 * However, if the IO is not aligned to filesystem blocks, the direct IO layer
647 * needs to do sub-block zeroing and that requires serialisation against other
648 * direct IOs to the same block. In this case we need to serialise the
649 * submission of the unaligned IOs so that we don't get racing block zeroing in
650 * the dio layer. To avoid the problem with aio, we also need to wait for
651 * outstanding IOs to complete so that unwritten extent conversion is completed
652 * before we try to map the overlapping block. This is currently implemented by
Christoph Hellwig4a06fd22011-08-23 08:28:13 +0000653 * hitting it with a big hammer (i.e. inode_dio_wait()).
Dave Chinnereda77982011-01-11 10:22:40 +1100654 *
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100655 * Returns with locks held indicated by @iolock and errors indicated by
656 * negative return values.
657 */
658STATIC ssize_t
659xfs_file_dio_aio_write(
660 struct kiocb *iocb,
Al Virob3188912014-04-02 07:06:30 -0400661 struct iov_iter *from)
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100662{
663 struct file *file = iocb->ki_filp;
664 struct address_space *mapping = file->f_mapping;
665 struct inode *inode = mapping->host;
666 struct xfs_inode *ip = XFS_I(inode);
667 struct xfs_mount *mp = ip->i_mount;
668 ssize_t ret = 0;
Dave Chinnereda77982011-01-11 10:22:40 +1100669 int unaligned_io = 0;
Christoph Hellwigd0606462011-12-18 20:00:14 +0000670 int iolock;
Al Virob3188912014-04-02 07:06:30 -0400671 size_t count = iov_iter_count(from);
672 loff_t pos = iocb->ki_pos;
Dave Chinner0cefb292015-04-16 22:03:27 +1000673 loff_t end;
674 struct iov_iter data;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100675 struct xfs_buftarg *target = XFS_IS_REALTIME_INODE(ip) ?
676 mp->m_rtdev_targp : mp->m_ddev_targp;
677
Eric Sandeen7c71ee72014-01-21 16:46:23 -0600678 /* DIO must be aligned to device logical sector size */
Dave Chinner6b698ed2015-06-04 09:18:53 +1000679 if (!IS_DAX(inode) && ((pos | count) & target->bt_logical_sectormask))
Eric Sandeenb474c7a2014-06-22 15:04:54 +1000680 return -EINVAL;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100681
Eric Sandeen7c71ee72014-01-21 16:46:23 -0600682 /* "unaligned" here means not aligned to a filesystem block */
Dave Chinnereda77982011-01-11 10:22:40 +1100683 if ((pos & mp->m_blockmask) || ((pos + count) & mp->m_blockmask))
684 unaligned_io = 1;
685
Dave Chinner7271d242011-08-25 07:17:02 +0000686 /*
687 * We don't need to take an exclusive lock unless there page cache needs
688 * to be invalidated or unaligned IO is being executed. We don't need to
689 * consider the EOF extension case here because
690 * xfs_file_aio_write_checks() will relock the inode as necessary for
691 * EOF zeroing cases and fill out the new inode size as appropriate.
692 */
693 if (unaligned_io || mapping->nrpages)
Christoph Hellwigd0606462011-12-18 20:00:14 +0000694 iolock = XFS_IOLOCK_EXCL;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100695 else
Christoph Hellwigd0606462011-12-18 20:00:14 +0000696 iolock = XFS_IOLOCK_SHARED;
697 xfs_rw_ilock(ip, iolock);
Christoph Hellwigc58cb162011-08-27 14:42:53 +0000698
699 /*
700 * Recheck if there are cached pages that need invalidate after we got
701 * the iolock to protect against other threads adding new pages while
702 * we were waiting for the iolock.
703 */
Christoph Hellwigd0606462011-12-18 20:00:14 +0000704 if (mapping->nrpages && iolock == XFS_IOLOCK_SHARED) {
705 xfs_rw_iunlock(ip, iolock);
706 iolock = XFS_IOLOCK_EXCL;
707 xfs_rw_ilock(ip, iolock);
Christoph Hellwigc58cb162011-08-27 14:42:53 +0000708 }
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100709
Al Viro99733fa2015-04-07 14:25:18 -0400710 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100711 if (ret)
Christoph Hellwigd0606462011-12-18 20:00:14 +0000712 goto out;
Al Viro99733fa2015-04-07 14:25:18 -0400713 count = iov_iter_count(from);
714 pos = iocb->ki_pos;
Dave Chinner0cefb292015-04-16 22:03:27 +1000715 end = pos + count - 1;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100716
717 if (mapping->nrpages) {
Dave Chinner07d50352014-04-17 08:15:27 +1000718 ret = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
Dave Chinner0cefb292015-04-16 22:03:27 +1000719 pos, end);
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100720 if (ret)
Christoph Hellwigd0606462011-12-18 20:00:14 +0000721 goto out;
Dave Chinner834ffca2014-09-02 12:12:52 +1000722 /*
723 * Invalidate whole pages. This can return an error if
724 * we fail to invalidate a page, but this should never
725 * happen on XFS. Warn if it does fail.
726 */
727 ret = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
Dave Chinner7d4ea3c2014-09-02 12:12:53 +1000728 pos >> PAGE_CACHE_SHIFT,
Dave Chinner0cefb292015-04-16 22:03:27 +1000729 end >> PAGE_CACHE_SHIFT);
Dave Chinner834ffca2014-09-02 12:12:52 +1000730 WARN_ON_ONCE(ret);
731 ret = 0;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100732 }
733
Dave Chinnereda77982011-01-11 10:22:40 +1100734 /*
735 * If we are doing unaligned IO, wait for all other IO to drain,
736 * otherwise demote the lock if we had to flush cached pages
737 */
738 if (unaligned_io)
Christoph Hellwig4a06fd22011-08-23 08:28:13 +0000739 inode_dio_wait(inode);
Christoph Hellwigd0606462011-12-18 20:00:14 +0000740 else if (iolock == XFS_IOLOCK_EXCL) {
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100741 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
Christoph Hellwigd0606462011-12-18 20:00:14 +0000742 iolock = XFS_IOLOCK_SHARED;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100743 }
744
745 trace_xfs_file_direct_write(ip, count, iocb->ki_pos, 0);
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100746
Dave Chinner0cefb292015-04-16 22:03:27 +1000747 data = *from;
Linus Torvalds1aef8822015-04-24 07:08:41 -0700748 ret = mapping->a_ops->direct_IO(iocb, &data, pos);
Dave Chinner0cefb292015-04-16 22:03:27 +1000749
750 /* see generic_file_direct_write() for why this is necessary */
751 if (mapping->nrpages) {
752 invalidate_inode_pages2_range(mapping,
753 pos >> PAGE_CACHE_SHIFT,
754 end >> PAGE_CACHE_SHIFT);
755 }
756
757 if (ret > 0) {
758 pos += ret;
759 iov_iter_advance(from, ret);
760 iocb->ki_pos = pos;
761 }
Christoph Hellwigd0606462011-12-18 20:00:14 +0000762out:
763 xfs_rw_iunlock(ip, iolock);
764
Dave Chinner6b698ed2015-06-04 09:18:53 +1000765 /*
766 * No fallback to buffered IO on errors for XFS. DAX can result in
767 * partial writes, but direct IO will either complete fully or fail.
768 */
769 ASSERT(ret < 0 || ret == count || IS_DAX(VFS_I(ip)));
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100770 return ret;
771}
772
Christoph Hellwig00258e32010-02-15 09:44:47 +0000773STATIC ssize_t
Dave Chinner637bbc72011-01-11 10:17:30 +1100774xfs_file_buffered_aio_write(
775 struct kiocb *iocb,
Al Virob3188912014-04-02 07:06:30 -0400776 struct iov_iter *from)
Dave Chinner637bbc72011-01-11 10:17:30 +1100777{
778 struct file *file = iocb->ki_filp;
779 struct address_space *mapping = file->f_mapping;
780 struct inode *inode = mapping->host;
781 struct xfs_inode *ip = XFS_I(inode);
782 ssize_t ret;
783 int enospc = 0;
Christoph Hellwigd0606462011-12-18 20:00:14 +0000784 int iolock = XFS_IOLOCK_EXCL;
Dave Chinner637bbc72011-01-11 10:17:30 +1100785
Christoph Hellwigd0606462011-12-18 20:00:14 +0000786 xfs_rw_ilock(ip, iolock);
Dave Chinner637bbc72011-01-11 10:17:30 +1100787
Al Viro99733fa2015-04-07 14:25:18 -0400788 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100789 if (ret)
Christoph Hellwigd0606462011-12-18 20:00:14 +0000790 goto out;
Dave Chinner637bbc72011-01-11 10:17:30 +1100791
792 /* We can write back this queue in page reclaim */
Christoph Hellwigde1414a2015-01-14 10:42:36 +0100793 current->backing_dev_info = inode_to_bdi(inode);
Dave Chinner637bbc72011-01-11 10:17:30 +1100794
795write_retry:
Al Viro99733fa2015-04-07 14:25:18 -0400796 trace_xfs_file_buffered_write(ip, iov_iter_count(from),
797 iocb->ki_pos, 0);
798 ret = generic_perform_write(file, from, iocb->ki_pos);
Al Viro0a64bc22014-02-11 22:25:22 -0500799 if (likely(ret >= 0))
Al Viro99733fa2015-04-07 14:25:18 -0400800 iocb->ki_pos += ret;
Brian Fosterdc06f3982014-07-24 19:49:28 +1000801
Dave Chinner637bbc72011-01-11 10:17:30 +1100802 /*
Brian Fosterdc06f3982014-07-24 19:49:28 +1000803 * If we hit a space limit, try to free up some lingering preallocated
804 * space before returning an error. In the case of ENOSPC, first try to
805 * write back all dirty inodes to free up some of the excess reserved
806 * metadata space. This reduces the chances that the eofblocks scan
807 * waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
808 * also behaves as a filter to prevent too many eofblocks scans from
809 * running at the same time.
Dave Chinner637bbc72011-01-11 10:17:30 +1100810 */
Brian Fosterdc06f3982014-07-24 19:49:28 +1000811 if (ret == -EDQUOT && !enospc) {
812 enospc = xfs_inode_free_quota_eofblocks(ip);
813 if (enospc)
814 goto write_retry;
815 } else if (ret == -ENOSPC && !enospc) {
816 struct xfs_eofblocks eofb = {0};
817
Dave Chinner637bbc72011-01-11 10:17:30 +1100818 enospc = 1;
Dave Chinner9aa05002012-10-08 21:56:04 +1100819 xfs_flush_inodes(ip->i_mount);
Brian Fosterdc06f3982014-07-24 19:49:28 +1000820 eofb.eof_scan_owner = ip->i_ino; /* for locking */
821 eofb.eof_flags = XFS_EOF_FLAGS_SYNC;
822 xfs_icache_free_eofblocks(ip->i_mount, &eofb);
Dave Chinner9aa05002012-10-08 21:56:04 +1100823 goto write_retry;
Dave Chinner637bbc72011-01-11 10:17:30 +1100824 }
Christoph Hellwigd0606462011-12-18 20:00:14 +0000825
Dave Chinner637bbc72011-01-11 10:17:30 +1100826 current->backing_dev_info = NULL;
Christoph Hellwigd0606462011-12-18 20:00:14 +0000827out:
828 xfs_rw_iunlock(ip, iolock);
Dave Chinner637bbc72011-01-11 10:17:30 +1100829 return ret;
830}
831
832STATIC ssize_t
Al Virobf97f3bc2014-04-03 14:20:23 -0400833xfs_file_write_iter(
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000834 struct kiocb *iocb,
Al Virobf97f3bc2014-04-03 14:20:23 -0400835 struct iov_iter *from)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000836{
837 struct file *file = iocb->ki_filp;
838 struct address_space *mapping = file->f_mapping;
839 struct inode *inode = mapping->host;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000840 struct xfs_inode *ip = XFS_I(inode);
Dave Chinner637bbc72011-01-11 10:17:30 +1100841 ssize_t ret;
Al Virobf97f3bc2014-04-03 14:20:23 -0400842 size_t ocount = iov_iter_count(from);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000843
844 XFS_STATS_INC(xs_write_calls);
845
Dave Chinner637bbc72011-01-11 10:17:30 +1100846 if (ocount == 0)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000847 return 0;
848
Al Virobf97f3bc2014-04-03 14:20:23 -0400849 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
850 return -EIO;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000851
Dave Chinner6b698ed2015-06-04 09:18:53 +1000852 if ((iocb->ki_flags & IOCB_DIRECT) || IS_DAX(inode))
Al Virobf97f3bc2014-04-03 14:20:23 -0400853 ret = xfs_file_dio_aio_write(iocb, from);
Dave Chinner637bbc72011-01-11 10:17:30 +1100854 else
Al Virobf97f3bc2014-04-03 14:20:23 -0400855 ret = xfs_file_buffered_aio_write(iocb, from);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000856
Christoph Hellwigd0606462011-12-18 20:00:14 +0000857 if (ret > 0) {
858 ssize_t err;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000859
Christoph Hellwigd0606462011-12-18 20:00:14 +0000860 XFS_STATS_ADD(xs_write_bytes, ret);
Christoph Hellwigce7ae1512011-12-18 20:00:11 +0000861
Christoph Hellwigd0606462011-12-18 20:00:14 +0000862 /* Handle various SYNC-type writes */
Al Virod311d792014-02-09 15:18:09 -0500863 err = generic_write_sync(file, iocb->ki_pos - ret, ret);
Christoph Hellwigd0606462011-12-18 20:00:14 +0000864 if (err < 0)
865 ret = err;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000866 }
Dave Chinnera363f0c2011-01-11 10:13:53 +1100867 return ret;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000868}
869
Namjae Jeona904b1c2015-03-25 15:08:56 +1100870#define XFS_FALLOC_FL_SUPPORTED \
871 (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
872 FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
873 FALLOC_FL_INSERT_RANGE)
874
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100875STATIC long
876xfs_file_fallocate(
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700877 struct file *file,
878 int mode,
879 loff_t offset,
880 loff_t len)
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100881{
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700882 struct inode *inode = file_inode(file);
883 struct xfs_inode *ip = XFS_I(inode);
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700884 long error;
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100885 enum xfs_prealloc_flags flags = 0;
Christoph Hellwig781355c2015-02-16 11:59:50 +1100886 uint iolock = XFS_IOLOCK_EXCL;
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700887 loff_t new_size = 0;
Namjae Jeona904b1c2015-03-25 15:08:56 +1100888 bool do_file_insert = 0;
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100889
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700890 if (!S_ISREG(inode->i_mode))
891 return -EINVAL;
Namjae Jeona904b1c2015-03-25 15:08:56 +1100892 if (mode & ~XFS_FALLOC_FL_SUPPORTED)
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100893 return -EOPNOTSUPP;
894
Christoph Hellwig781355c2015-02-16 11:59:50 +1100895 xfs_ilock(ip, iolock);
Christoph Hellwig21c3ea12015-04-13 11:38:29 +1000896 error = xfs_break_layouts(inode, &iolock, false);
Christoph Hellwig781355c2015-02-16 11:59:50 +1100897 if (error)
898 goto out_unlock;
899
Dave Chinnere8e9ad42015-02-23 21:45:32 +1100900 xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
901 iolock |= XFS_MMAPLOCK_EXCL;
902
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700903 if (mode & FALLOC_FL_PUNCH_HOLE) {
904 error = xfs_free_file_space(ip, offset, len);
905 if (error)
906 goto out_unlock;
Namjae Jeone1d8fb82014-02-24 10:58:19 +1100907 } else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
908 unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
909
910 if (offset & blksize_mask || len & blksize_mask) {
Dave Chinner24513372014-06-25 14:58:08 +1000911 error = -EINVAL;
Namjae Jeone1d8fb82014-02-24 10:58:19 +1100912 goto out_unlock;
913 }
914
Lukas Czerner23fffa92014-04-12 09:56:41 -0400915 /*
916 * There is no need to overlap collapse range with EOF,
917 * in which case it is effectively a truncate operation
918 */
919 if (offset + len >= i_size_read(inode)) {
Dave Chinner24513372014-06-25 14:58:08 +1000920 error = -EINVAL;
Lukas Czerner23fffa92014-04-12 09:56:41 -0400921 goto out_unlock;
922 }
923
Namjae Jeone1d8fb82014-02-24 10:58:19 +1100924 new_size = i_size_read(inode) - len;
925
926 error = xfs_collapse_file_space(ip, offset, len);
927 if (error)
928 goto out_unlock;
Namjae Jeona904b1c2015-03-25 15:08:56 +1100929 } else if (mode & FALLOC_FL_INSERT_RANGE) {
930 unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
931
932 new_size = i_size_read(inode) + len;
933 if (offset & blksize_mask || len & blksize_mask) {
934 error = -EINVAL;
935 goto out_unlock;
936 }
937
938 /* check the new inode size does not wrap through zero */
939 if (new_size > inode->i_sb->s_maxbytes) {
940 error = -EFBIG;
941 goto out_unlock;
942 }
943
944 /* Offset should be less than i_size */
945 if (offset >= i_size_read(inode)) {
946 error = -EINVAL;
947 goto out_unlock;
948 }
949 do_file_insert = 1;
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700950 } else {
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100951 flags |= XFS_PREALLOC_SET;
952
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700953 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
954 offset + len > i_size_read(inode)) {
955 new_size = offset + len;
Dave Chinner24513372014-06-25 14:58:08 +1000956 error = inode_newsize_ok(inode, new_size);
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700957 if (error)
958 goto out_unlock;
959 }
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100960
Lukas Czerner376ba312014-03-13 19:07:58 +1100961 if (mode & FALLOC_FL_ZERO_RANGE)
962 error = xfs_zero_file_space(ip, offset, len);
963 else
964 error = xfs_alloc_file_space(ip, offset, len,
965 XFS_BMAPI_PREALLOC);
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100966 if (error)
967 goto out_unlock;
968 }
969
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700970 if (file->f_flags & O_DSYNC)
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100971 flags |= XFS_PREALLOC_SYNC;
972
973 error = xfs_update_prealloc_flags(ip, flags);
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100974 if (error)
975 goto out_unlock;
976
977 /* Change file size if needed */
978 if (new_size) {
979 struct iattr iattr;
980
981 iattr.ia_valid = ATTR_SIZE;
982 iattr.ia_size = new_size;
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700983 error = xfs_setattr_size(ip, &iattr);
Namjae Jeona904b1c2015-03-25 15:08:56 +1100984 if (error)
985 goto out_unlock;
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100986 }
987
Namjae Jeona904b1c2015-03-25 15:08:56 +1100988 /*
989 * Perform hole insertion now that the file size has been
990 * updated so that if we crash during the operation we don't
991 * leave shifted extents past EOF and hence losing access to
992 * the data that is contained within them.
993 */
994 if (do_file_insert)
995 error = xfs_insert_file_space(ip, offset, len);
996
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100997out_unlock:
Christoph Hellwig781355c2015-02-16 11:59:50 +1100998 xfs_iunlock(ip, iolock);
Dave Chinner24513372014-06-25 14:58:08 +1000999 return error;
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001000}
1001
1002
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003STATIC int
Nathan Scott3562fd42006-03-14 14:00:35 +11001004xfs_file_open(
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005 struct inode *inode,
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001006 struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007{
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001008 if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009 return -EFBIG;
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001010 if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
1011 return -EIO;
1012 return 0;
1013}
1014
1015STATIC int
1016xfs_dir_open(
1017 struct inode *inode,
1018 struct file *file)
1019{
1020 struct xfs_inode *ip = XFS_I(inode);
1021 int mode;
1022 int error;
1023
1024 error = xfs_file_open(inode, file);
1025 if (error)
1026 return error;
1027
1028 /*
1029 * If there are any blocks, read-ahead block 0 as we're almost
1030 * certain to have the next operation be a read there.
1031 */
Christoph Hellwig309ecac2013-12-06 12:30:09 -08001032 mode = xfs_ilock_data_map_shared(ip);
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001033 if (ip->i_d.di_nextents > 0)
Eric Sandeen9df2dd02014-04-14 19:01:59 +10001034 xfs_dir3_data_readahead(ip, 0, -1);
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001035 xfs_iunlock(ip, mode);
1036 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001037}
1038
Linus Torvalds1da177e2005-04-16 15:20:36 -07001039STATIC int
Nathan Scott3562fd42006-03-14 14:00:35 +11001040xfs_file_release(
Linus Torvalds1da177e2005-04-16 15:20:36 -07001041 struct inode *inode,
1042 struct file *filp)
1043{
Dave Chinner24513372014-06-25 14:58:08 +10001044 return xfs_release(XFS_I(inode));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001045}
1046
Linus Torvalds1da177e2005-04-16 15:20:36 -07001047STATIC int
Nathan Scott3562fd42006-03-14 14:00:35 +11001048xfs_file_readdir(
Al Virob8227552013-05-22 17:07:56 -04001049 struct file *file,
1050 struct dir_context *ctx)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051{
Al Virob8227552013-05-22 17:07:56 -04001052 struct inode *inode = file_inode(file);
Christoph Hellwig739bfb22007-08-29 10:58:01 +10001053 xfs_inode_t *ip = XFS_I(inode);
Christoph Hellwig051e7cd2007-08-28 13:58:24 +10001054 size_t bufsize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055
Christoph Hellwig051e7cd2007-08-28 13:58:24 +10001056 /*
1057 * The Linux API doesn't pass down the total size of the buffer
1058 * we read into down to the filesystem. With the filldir concept
1059 * it's not needed for correct information, but the XFS dir2 leaf
1060 * code wants an estimate of the buffer size to calculate it's
1061 * readahead window and size the buffers used for mapping to
1062 * physical blocks.
1063 *
1064 * Try to give it an estimate that's good enough, maybe at some
1065 * point we can change the ->readdir prototype to include the
Eric Sandeena9cc7992010-02-03 17:50:13 +00001066 * buffer size. For now we use the current glibc buffer size.
Christoph Hellwig051e7cd2007-08-28 13:58:24 +10001067 */
Eric Sandeena9cc7992010-02-03 17:50:13 +00001068 bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069
kbuild test robot83004752014-12-01 08:25:28 +11001070 return xfs_readdir(ip, ctx, bufsize);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001071}
1072
David Chinner4f57dbc2007-07-19 16:28:17 +10001073/*
Jeff Liud126d432012-08-21 17:11:57 +08001074 * This type is designed to indicate the type of offset we would like
Eric Sandeen49c69592014-09-09 11:56:48 +10001075 * to search from page cache for xfs_seek_hole_data().
Jeff Liud126d432012-08-21 17:11:57 +08001076 */
1077enum {
1078 HOLE_OFF = 0,
1079 DATA_OFF,
1080};
1081
1082/*
1083 * Lookup the desired type of offset from the given page.
1084 *
1085 * On success, return true and the offset argument will point to the
1086 * start of the region that was found. Otherwise this function will
1087 * return false and keep the offset argument unchanged.
1088 */
1089STATIC bool
1090xfs_lookup_buffer_offset(
1091 struct page *page,
1092 loff_t *offset,
1093 unsigned int type)
1094{
1095 loff_t lastoff = page_offset(page);
1096 bool found = false;
1097 struct buffer_head *bh, *head;
1098
1099 bh = head = page_buffers(page);
1100 do {
1101 /*
1102 * Unwritten extents that have data in the page
1103 * cache covering them can be identified by the
1104 * BH_Unwritten state flag. Pages with multiple
1105 * buffers might have a mix of holes, data and
1106 * unwritten extents - any buffer with valid
1107 * data in it should have BH_Uptodate flag set
1108 * on it.
1109 */
1110 if (buffer_unwritten(bh) ||
1111 buffer_uptodate(bh)) {
1112 if (type == DATA_OFF)
1113 found = true;
1114 } else {
1115 if (type == HOLE_OFF)
1116 found = true;
1117 }
1118
1119 if (found) {
1120 *offset = lastoff;
1121 break;
1122 }
1123 lastoff += bh->b_size;
1124 } while ((bh = bh->b_this_page) != head);
1125
1126 return found;
1127}
1128
1129/*
1130 * This routine is called to find out and return a data or hole offset
1131 * from the page cache for unwritten extents according to the desired
Eric Sandeen49c69592014-09-09 11:56:48 +10001132 * type for xfs_seek_hole_data().
Jeff Liud126d432012-08-21 17:11:57 +08001133 *
1134 * The argument offset is used to tell where we start to search from the
1135 * page cache. Map is used to figure out the end points of the range to
1136 * lookup pages.
1137 *
1138 * Return true if the desired type of offset was found, and the argument
1139 * offset is filled with that address. Otherwise, return false and keep
1140 * offset unchanged.
1141 */
1142STATIC bool
1143xfs_find_get_desired_pgoff(
1144 struct inode *inode,
1145 struct xfs_bmbt_irec *map,
1146 unsigned int type,
1147 loff_t *offset)
1148{
1149 struct xfs_inode *ip = XFS_I(inode);
1150 struct xfs_mount *mp = ip->i_mount;
1151 struct pagevec pvec;
1152 pgoff_t index;
1153 pgoff_t end;
1154 loff_t endoff;
1155 loff_t startoff = *offset;
1156 loff_t lastoff = startoff;
1157 bool found = false;
1158
1159 pagevec_init(&pvec, 0);
1160
1161 index = startoff >> PAGE_CACHE_SHIFT;
1162 endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
1163 end = endoff >> PAGE_CACHE_SHIFT;
1164 do {
1165 int want;
1166 unsigned nr_pages;
1167 unsigned int i;
1168
1169 want = min_t(pgoff_t, end - index, PAGEVEC_SIZE);
1170 nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
1171 want);
1172 /*
1173 * No page mapped into given range. If we are searching holes
1174 * and if this is the first time we got into the loop, it means
1175 * that the given offset is landed in a hole, return it.
1176 *
1177 * If we have already stepped through some block buffers to find
1178 * holes but they all contains data. In this case, the last
1179 * offset is already updated and pointed to the end of the last
1180 * mapped page, if it does not reach the endpoint to search,
1181 * that means there should be a hole between them.
1182 */
1183 if (nr_pages == 0) {
1184 /* Data search found nothing */
1185 if (type == DATA_OFF)
1186 break;
1187
1188 ASSERT(type == HOLE_OFF);
1189 if (lastoff == startoff || lastoff < endoff) {
1190 found = true;
1191 *offset = lastoff;
1192 }
1193 break;
1194 }
1195
1196 /*
1197 * At lease we found one page. If this is the first time we
1198 * step into the loop, and if the first page index offset is
1199 * greater than the given search offset, a hole was found.
1200 */
1201 if (type == HOLE_OFF && lastoff == startoff &&
1202 lastoff < page_offset(pvec.pages[0])) {
1203 found = true;
1204 break;
1205 }
1206
1207 for (i = 0; i < nr_pages; i++) {
1208 struct page *page = pvec.pages[i];
1209 loff_t b_offset;
1210
1211 /*
1212 * At this point, the page may be truncated or
1213 * invalidated (changing page->mapping to NULL),
1214 * or even swizzled back from swapper_space to tmpfs
1215 * file mapping. However, page->index will not change
1216 * because we have a reference on the page.
1217 *
1218 * Searching done if the page index is out of range.
1219 * If the current offset is not reaches the end of
1220 * the specified search range, there should be a hole
1221 * between them.
1222 */
1223 if (page->index > end) {
1224 if (type == HOLE_OFF && lastoff < endoff) {
1225 *offset = lastoff;
1226 found = true;
1227 }
1228 goto out;
1229 }
1230
1231 lock_page(page);
1232 /*
1233 * Page truncated or invalidated(page->mapping == NULL).
1234 * We can freely skip it and proceed to check the next
1235 * page.
1236 */
1237 if (unlikely(page->mapping != inode->i_mapping)) {
1238 unlock_page(page);
1239 continue;
1240 }
1241
1242 if (!page_has_buffers(page)) {
1243 unlock_page(page);
1244 continue;
1245 }
1246
1247 found = xfs_lookup_buffer_offset(page, &b_offset, type);
1248 if (found) {
1249 /*
1250 * The found offset may be less than the start
1251 * point to search if this is the first time to
1252 * come here.
1253 */
1254 *offset = max_t(loff_t, startoff, b_offset);
1255 unlock_page(page);
1256 goto out;
1257 }
1258
1259 /*
1260 * We either searching data but nothing was found, or
1261 * searching hole but found a data buffer. In either
1262 * case, probably the next page contains the desired
1263 * things, update the last offset to it so.
1264 */
1265 lastoff = page_offset(page) + PAGE_SIZE;
1266 unlock_page(page);
1267 }
1268
1269 /*
1270 * The number of returned pages less than our desired, search
1271 * done. In this case, nothing was found for searching data,
1272 * but we found a hole behind the last offset.
1273 */
1274 if (nr_pages < want) {
1275 if (type == HOLE_OFF) {
1276 *offset = lastoff;
1277 found = true;
1278 }
1279 break;
1280 }
1281
1282 index = pvec.pages[i - 1]->index + 1;
1283 pagevec_release(&pvec);
1284 } while (index <= end);
1285
1286out:
1287 pagevec_release(&pvec);
1288 return found;
1289}
1290
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001291STATIC loff_t
Eric Sandeen49c69592014-09-09 11:56:48 +10001292xfs_seek_hole_data(
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001293 struct file *file,
Eric Sandeen49c69592014-09-09 11:56:48 +10001294 loff_t start,
1295 int whence)
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001296{
1297 struct inode *inode = file->f_mapping->host;
1298 struct xfs_inode *ip = XFS_I(inode);
1299 struct xfs_mount *mp = ip->i_mount;
1300 loff_t uninitialized_var(offset);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001301 xfs_fsize_t isize;
1302 xfs_fileoff_t fsbno;
Jeff Liub686d1f2012-08-21 17:12:18 +08001303 xfs_filblks_t end;
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001304 uint lock;
1305 int error;
1306
1307 if (XFS_FORCED_SHUTDOWN(mp))
Eric Sandeenb474c7a2014-06-22 15:04:54 +10001308 return -EIO;
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001309
Christoph Hellwig309ecac2013-12-06 12:30:09 -08001310 lock = xfs_ilock_data_map_shared(ip);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001311
1312 isize = i_size_read(inode);
1313 if (start >= isize) {
Dave Chinner24513372014-06-25 14:58:08 +10001314 error = -ENXIO;
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001315 goto out_unlock;
1316 }
1317
Eric Sandeen49c69592014-09-09 11:56:48 +10001318 /*
1319 * Try to read extents from the first block indicated
1320 * by fsbno to the end block of the file.
1321 */
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001322 fsbno = XFS_B_TO_FSBT(mp, start);
Jeff Liub686d1f2012-08-21 17:12:18 +08001323 end = XFS_B_TO_FSB(mp, isize);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001324
Jeff Liub686d1f2012-08-21 17:12:18 +08001325 for (;;) {
1326 struct xfs_bmbt_irec map[2];
1327 int nmap = 2;
1328 unsigned int i;
1329
1330 error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap,
1331 XFS_BMAPI_ENTIRE);
1332 if (error)
1333 goto out_unlock;
1334
1335 /* No extents at given offset, must be beyond EOF */
1336 if (nmap == 0) {
Dave Chinner24513372014-06-25 14:58:08 +10001337 error = -ENXIO;
Jeff Liub686d1f2012-08-21 17:12:18 +08001338 goto out_unlock;
1339 }
1340
1341 for (i = 0; i < nmap; i++) {
1342 offset = max_t(loff_t, start,
1343 XFS_FSB_TO_B(mp, map[i].br_startoff));
1344
Eric Sandeen49c69592014-09-09 11:56:48 +10001345 /* Landed in the hole we wanted? */
1346 if (whence == SEEK_HOLE &&
1347 map[i].br_startblock == HOLESTARTBLOCK)
1348 goto out;
1349
1350 /* Landed in the data extent we wanted? */
1351 if (whence == SEEK_DATA &&
1352 (map[i].br_startblock == DELAYSTARTBLOCK ||
1353 (map[i].br_state == XFS_EXT_NORM &&
1354 !isnullstartblock(map[i].br_startblock))))
Jeff Liub686d1f2012-08-21 17:12:18 +08001355 goto out;
1356
1357 /*
Eric Sandeen49c69592014-09-09 11:56:48 +10001358 * Landed in an unwritten extent, try to search
1359 * for hole or data from page cache.
Jeff Liub686d1f2012-08-21 17:12:18 +08001360 */
1361 if (map[i].br_state == XFS_EXT_UNWRITTEN) {
1362 if (xfs_find_get_desired_pgoff(inode, &map[i],
Eric Sandeen49c69592014-09-09 11:56:48 +10001363 whence == SEEK_HOLE ? HOLE_OFF : DATA_OFF,
1364 &offset))
Jeff Liub686d1f2012-08-21 17:12:18 +08001365 goto out;
1366 }
1367 }
1368
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001369 /*
Eric Sandeen49c69592014-09-09 11:56:48 +10001370 * We only received one extent out of the two requested. This
1371 * means we've hit EOF and didn't find what we are looking for.
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001372 */
Jeff Liub686d1f2012-08-21 17:12:18 +08001373 if (nmap == 1) {
Eric Sandeen49c69592014-09-09 11:56:48 +10001374 /*
1375 * If we were looking for a hole, set offset to
1376 * the end of the file (i.e., there is an implicit
1377 * hole at the end of any file).
1378 */
1379 if (whence == SEEK_HOLE) {
1380 offset = isize;
1381 break;
1382 }
1383 /*
1384 * If we were looking for data, it's nowhere to be found
1385 */
1386 ASSERT(whence == SEEK_DATA);
1387 error = -ENXIO;
1388 goto out_unlock;
Jeff Liub686d1f2012-08-21 17:12:18 +08001389 }
1390
1391 ASSERT(i > 1);
1392
1393 /*
Eric Sandeen49c69592014-09-09 11:56:48 +10001394 * Nothing was found, proceed to the next round of search
1395 * if the next reading offset is not at or beyond EOF.
Jeff Liub686d1f2012-08-21 17:12:18 +08001396 */
1397 fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount;
1398 start = XFS_FSB_TO_B(mp, fsbno);
1399 if (start >= isize) {
Eric Sandeen49c69592014-09-09 11:56:48 +10001400 if (whence == SEEK_HOLE) {
1401 offset = isize;
1402 break;
1403 }
1404 ASSERT(whence == SEEK_DATA);
1405 error = -ENXIO;
1406 goto out_unlock;
Jeff Liub686d1f2012-08-21 17:12:18 +08001407 }
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001408 }
1409
Jeff Liub686d1f2012-08-21 17:12:18 +08001410out:
1411 /*
Eric Sandeen49c69592014-09-09 11:56:48 +10001412 * If at this point we have found the hole we wanted, the returned
Jeff Liub686d1f2012-08-21 17:12:18 +08001413 * offset may be bigger than the file size as it may be aligned to
Eric Sandeen49c69592014-09-09 11:56:48 +10001414 * page boundary for unwritten extents. We need to deal with this
Jeff Liub686d1f2012-08-21 17:12:18 +08001415 * situation in particular.
1416 */
Eric Sandeen49c69592014-09-09 11:56:48 +10001417 if (whence == SEEK_HOLE)
1418 offset = min_t(loff_t, offset, isize);
Jie Liu46a1c2c2013-06-25 12:02:13 +08001419 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001420
1421out_unlock:
Christoph Hellwig01f4f322013-12-06 12:30:08 -08001422 xfs_iunlock(ip, lock);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001423
1424 if (error)
Dave Chinner24513372014-06-25 14:58:08 +10001425 return error;
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001426 return offset;
1427}
1428
1429STATIC loff_t
1430xfs_file_llseek(
1431 struct file *file,
1432 loff_t offset,
Eric Sandeen59f9c002014-09-09 11:57:10 +10001433 int whence)
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001434{
Eric Sandeen59f9c002014-09-09 11:57:10 +10001435 switch (whence) {
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001436 case SEEK_END:
1437 case SEEK_CUR:
1438 case SEEK_SET:
Eric Sandeen59f9c002014-09-09 11:57:10 +10001439 return generic_file_llseek(file, offset, whence);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001440 case SEEK_HOLE:
Eric Sandeen49c69592014-09-09 11:56:48 +10001441 case SEEK_DATA:
Eric Sandeen59f9c002014-09-09 11:57:10 +10001442 return xfs_seek_hole_data(file, offset, whence);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001443 default:
1444 return -EINVAL;
1445 }
1446}
1447
Dave Chinnerde0e8c22015-02-23 21:44:19 +11001448/*
1449 * Locking for serialisation of IO during page faults. This results in a lock
1450 * ordering of:
1451 *
1452 * mmap_sem (MM)
Dave Chinner6b698ed2015-06-04 09:18:53 +10001453 * sb_start_pagefault(vfs, freeze)
1454 * i_mmap_lock (XFS - truncate serialisation)
1455 * page_lock (MM)
1456 * i_lock (XFS - extent map serialisation)
Dave Chinnerde0e8c22015-02-23 21:44:19 +11001457 */
Dave Chinnerde0e8c22015-02-23 21:44:19 +11001458
Dave Chinner075a9242015-02-23 21:44:54 +11001459/*
1460 * mmap()d file has taken write protection fault and is being made writable. We
1461 * can set the page state up correctly for a writable page, which means we can
1462 * do correct delalloc accounting (ENOSPC checking!) and unwritten extent
1463 * mapping.
1464 */
1465STATIC int
1466xfs_filemap_page_mkwrite(
1467 struct vm_area_struct *vma,
1468 struct vm_fault *vmf)
1469{
Dave Chinner6b698ed2015-06-04 09:18:53 +10001470 struct inode *inode = file_inode(vma->vm_file);
Dave Chinnerec56b1f2015-06-04 09:18:18 +10001471 int ret;
Dave Chinner075a9242015-02-23 21:44:54 +11001472
Dave Chinner6b698ed2015-06-04 09:18:53 +10001473 trace_xfs_filemap_page_mkwrite(XFS_I(inode));
Dave Chinner075a9242015-02-23 21:44:54 +11001474
Dave Chinner6b698ed2015-06-04 09:18:53 +10001475 sb_start_pagefault(inode->i_sb);
Dave Chinnerec56b1f2015-06-04 09:18:18 +10001476 file_update_time(vma->vm_file);
Dave Chinner6b698ed2015-06-04 09:18:53 +10001477 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1478
1479 if (IS_DAX(inode)) {
1480 ret = __dax_mkwrite(vma, vmf, xfs_get_blocks_direct,
1481 xfs_end_io_dax_write);
1482 } else {
1483 ret = __block_page_mkwrite(vma, vmf, xfs_get_blocks);
1484 ret = block_page_mkwrite_return(ret);
1485 }
1486
1487 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1488 sb_end_pagefault(inode->i_sb);
1489
1490 return ret;
1491}
1492
1493STATIC int
1494xfs_filemap_fault(
1495 struct vm_area_struct *vma,
1496 struct vm_fault *vmf)
1497{
1498 struct xfs_inode *ip = XFS_I(file_inode(vma->vm_file));
1499 int ret;
1500
1501 trace_xfs_filemap_fault(ip);
1502
1503 /* DAX can shortcut the normal fault path on write faults! */
1504 if ((vmf->flags & FAULT_FLAG_WRITE) && IS_DAX(VFS_I(ip)))
1505 return xfs_filemap_page_mkwrite(vma, vmf);
1506
Dave Chinner075a9242015-02-23 21:44:54 +11001507 xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
Dave Chinner6b698ed2015-06-04 09:18:53 +10001508 ret = filemap_fault(vma, vmf);
Dave Chinnerec56b1f2015-06-04 09:18:18 +10001509 xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
Dave Chinnerec56b1f2015-06-04 09:18:18 +10001510
Dave Chinner6b698ed2015-06-04 09:18:53 +10001511 return ret;
1512}
1513
1514static const struct vm_operations_struct xfs_file_vm_ops = {
1515 .fault = xfs_filemap_fault,
1516 .map_pages = filemap_map_pages,
1517 .page_mkwrite = xfs_filemap_page_mkwrite,
1518};
1519
1520STATIC int
1521xfs_file_mmap(
1522 struct file *filp,
1523 struct vm_area_struct *vma)
1524{
1525 file_accessed(filp);
1526 vma->vm_ops = &xfs_file_vm_ops;
1527 if (IS_DAX(file_inode(filp)))
1528 vma->vm_flags |= VM_MIXEDMAP;
1529 return 0;
Dave Chinner075a9242015-02-23 21:44:54 +11001530}
1531
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08001532const struct file_operations xfs_file_operations = {
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001533 .llseek = xfs_file_llseek,
Al Virob4f5d2c2014-04-02 14:37:59 -04001534 .read_iter = xfs_file_read_iter,
Al Virobf97f3bc2014-04-03 14:20:23 -04001535 .write_iter = xfs_file_write_iter,
Nathan Scott1b895842006-03-31 13:08:59 +10001536 .splice_read = xfs_file_splice_read,
Al Viro8d020762014-04-05 04:27:08 -04001537 .splice_write = iter_file_splice_write,
Nathan Scott3562fd42006-03-14 14:00:35 +11001538 .unlocked_ioctl = xfs_file_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001539#ifdef CONFIG_COMPAT
Nathan Scott3562fd42006-03-14 14:00:35 +11001540 .compat_ioctl = xfs_file_compat_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001541#endif
Nathan Scott3562fd42006-03-14 14:00:35 +11001542 .mmap = xfs_file_mmap,
1543 .open = xfs_file_open,
1544 .release = xfs_file_release,
1545 .fsync = xfs_file_fsync,
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001546 .fallocate = xfs_file_fallocate,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001547};
1548
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08001549const struct file_operations xfs_dir_file_operations = {
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001550 .open = xfs_dir_open,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551 .read = generic_read_dir,
Al Virob8227552013-05-22 17:07:56 -04001552 .iterate = xfs_file_readdir,
Al Viro59af1582008-08-24 07:24:41 -04001553 .llseek = generic_file_llseek,
Nathan Scott3562fd42006-03-14 14:00:35 +11001554 .unlocked_ioctl = xfs_file_ioctl,
Nathan Scottd3870392005-05-06 06:44:46 -07001555#ifdef CONFIG_COMPAT
Nathan Scott3562fd42006-03-14 14:00:35 +11001556 .compat_ioctl = xfs_file_compat_ioctl,
Nathan Scottd3870392005-05-06 06:44:46 -07001557#endif
Christoph Hellwig1da2f2d2011-10-02 14:25:16 +00001558 .fsync = xfs_dir_fsync,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001559};