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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>
Tejun Heo66114ca2015-05-22 17:13:32 -040044#include <linux/backing-dev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +040046static const struct vm_operations_struct xfs_file_vm_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
Christoph Hellwigdda35b82010-02-15 09:44:46 +000048/*
Dave Chinner487f84f2011-01-12 11:37:10 +110049 * Locking primitives for read and write IO paths to ensure we consistently use
50 * and order the inode->i_mutex, ip->i_lock and ip->i_iolock.
51 */
52static inline void
53xfs_rw_ilock(
54 struct xfs_inode *ip,
55 int type)
56{
57 if (type & XFS_IOLOCK_EXCL)
58 mutex_lock(&VFS_I(ip)->i_mutex);
59 xfs_ilock(ip, type);
60}
61
62static inline void
63xfs_rw_iunlock(
64 struct xfs_inode *ip,
65 int type)
66{
67 xfs_iunlock(ip, type);
68 if (type & XFS_IOLOCK_EXCL)
69 mutex_unlock(&VFS_I(ip)->i_mutex);
70}
71
72static inline void
73xfs_rw_ilock_demote(
74 struct xfs_inode *ip,
75 int type)
76{
77 xfs_ilock_demote(ip, type);
78 if (type & XFS_IOLOCK_EXCL)
79 mutex_unlock(&VFS_I(ip)->i_mutex);
80}
81
82/*
Dave Chinner4f69f572015-06-04 09:19:08 +100083 * xfs_iozero clears the specified range supplied via the page cache (except in
84 * the DAX case). Writes through the page cache will allocate blocks over holes,
85 * though the callers usually map the holes first and avoid them. If a block is
86 * not completely zeroed, then it will be read from disk before being partially
87 * zeroed.
Christoph Hellwigdda35b82010-02-15 09:44:46 +000088 *
Dave Chinner4f69f572015-06-04 09:19:08 +100089 * In the DAX case, we can just directly write to the underlying pages. This
90 * will not allocate blocks, but will avoid holes and unwritten extents and so
91 * not do unnecessary work.
Christoph Hellwigdda35b82010-02-15 09:44:46 +000092 */
Dave Chinneref9d8732012-11-29 15:26:33 +110093int
Christoph Hellwigdda35b82010-02-15 09:44:46 +000094xfs_iozero(
95 struct xfs_inode *ip, /* inode */
96 loff_t pos, /* offset in file */
97 size_t count) /* size of data to zero */
98{
99 struct page *page;
100 struct address_space *mapping;
Dave Chinner4f69f572015-06-04 09:19:08 +1000101 int status = 0;
102
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000103
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
Dave Chinner4f69f572015-06-04 09:19:08 +1000114 if (IS_DAX(VFS_I(ip))) {
115 status = dax_zero_page_range(VFS_I(ip), pos, bytes,
116 xfs_get_blocks_direct);
117 if (status)
118 break;
119 } else {
120 status = pagecache_write_begin(NULL, mapping, pos, bytes,
121 AOP_FLAG_UNINTERRUPTIBLE,
122 &page, &fsdata);
123 if (status)
124 break;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000125
Dave Chinner4f69f572015-06-04 09:19:08 +1000126 zero_user(page, offset, bytes);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000127
Dave Chinner4f69f572015-06-04 09:19:08 +1000128 status = pagecache_write_end(NULL, mapping, pos, bytes,
129 bytes, page, fsdata);
130 WARN_ON(status <= 0); /* can't return less than zero! */
131 status = 0;
132 }
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000133 pos += bytes;
134 count -= bytes;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000135 } while (count);
136
Dave Chinnercddc1162015-05-29 07:40:32 +1000137 return status;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000138}
139
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100140int
141xfs_update_prealloc_flags(
142 struct xfs_inode *ip,
143 enum xfs_prealloc_flags flags)
144{
145 struct xfs_trans *tp;
146 int error;
147
148 tp = xfs_trans_alloc(ip->i_mount, XFS_TRANS_WRITEID);
149 error = xfs_trans_reserve(tp, &M_RES(ip->i_mount)->tr_writeid, 0, 0);
150 if (error) {
Christoph Hellwig4906e212015-06-04 13:47:56 +1000151 xfs_trans_cancel(tp);
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100152 return error;
153 }
154
155 xfs_ilock(ip, XFS_ILOCK_EXCL);
156 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
157
158 if (!(flags & XFS_PREALLOC_INVISIBLE)) {
159 ip->i_d.di_mode &= ~S_ISUID;
160 if (ip->i_d.di_mode & S_IXGRP)
161 ip->i_d.di_mode &= ~S_ISGID;
162 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
163 }
164
165 if (flags & XFS_PREALLOC_SET)
166 ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
167 if (flags & XFS_PREALLOC_CLEAR)
168 ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC;
169
170 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
171 if (flags & XFS_PREALLOC_SYNC)
172 xfs_trans_set_sync(tp);
Christoph Hellwig70393312015-06-04 13:48:08 +1000173 return xfs_trans_commit(tp);
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100174}
175
Christoph Hellwig1da2f2d2011-10-02 14:25:16 +0000176/*
177 * Fsync operations on directories are much simpler than on regular files,
178 * as there is no file data to flush, and thus also no need for explicit
179 * cache flush operations, and there are no non-transaction metadata updates
180 * on directories either.
181 */
182STATIC int
183xfs_dir_fsync(
184 struct file *file,
185 loff_t start,
186 loff_t end,
187 int datasync)
188{
189 struct xfs_inode *ip = XFS_I(file->f_mapping->host);
190 struct xfs_mount *mp = ip->i_mount;
191 xfs_lsn_t lsn = 0;
192
193 trace_xfs_dir_fsync(ip);
194
195 xfs_ilock(ip, XFS_ILOCK_SHARED);
196 if (xfs_ipincount(ip))
197 lsn = ip->i_itemp->ili_last_lsn;
198 xfs_iunlock(ip, XFS_ILOCK_SHARED);
199
200 if (!lsn)
201 return 0;
Dave Chinner24513372014-06-25 14:58:08 +1000202 return _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, NULL);
Christoph Hellwig1da2f2d2011-10-02 14:25:16 +0000203}
204
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000205STATIC int
206xfs_file_fsync(
207 struct file *file,
Josef Bacik02c24a82011-07-16 20:44:56 -0400208 loff_t start,
209 loff_t end,
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000210 int datasync)
211{
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200212 struct inode *inode = file->f_mapping->host;
213 struct xfs_inode *ip = XFS_I(inode);
Christoph Hellwiga27a2632011-06-16 12:02:23 +0000214 struct xfs_mount *mp = ip->i_mount;
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000215 int error = 0;
216 int log_flushed = 0;
Christoph Hellwigb1037052011-09-19 14:55:51 +0000217 xfs_lsn_t lsn = 0;
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000218
Christoph Hellwigcca28fb2010-06-24 11:57:09 +1000219 trace_xfs_file_fsync(ip);
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000220
Josef Bacik02c24a82011-07-16 20:44:56 -0400221 error = filemap_write_and_wait_range(inode->i_mapping, start, end);
222 if (error)
223 return error;
224
Christoph Hellwiga27a2632011-06-16 12:02:23 +0000225 if (XFS_FORCED_SHUTDOWN(mp))
Eric Sandeenb474c7a2014-06-22 15:04:54 +1000226 return -EIO;
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000227
228 xfs_iflags_clear(ip, XFS_ITRUNCATED);
229
Christoph Hellwiga27a2632011-06-16 12:02:23 +0000230 if (mp->m_flags & XFS_MOUNT_BARRIER) {
231 /*
232 * If we have an RT and/or log subvolume we need to make sure
233 * to flush the write cache the device used for file data
234 * first. This is to ensure newly written file data make
235 * it to disk before logging the new inode size in case of
236 * an extending write.
237 */
238 if (XFS_IS_REALTIME_INODE(ip))
239 xfs_blkdev_issue_flush(mp->m_rtdev_targp);
240 else if (mp->m_logdev_targp != mp->m_ddev_targp)
241 xfs_blkdev_issue_flush(mp->m_ddev_targp);
242 }
243
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000244 /*
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000245 * All metadata updates are logged, which means that we just have
246 * to flush the log up to the latest LSN that touched the inode.
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000247 */
248 xfs_ilock(ip, XFS_ILOCK_SHARED);
Christoph Hellwig8f639dd2012-02-29 09:53:55 +0000249 if (xfs_ipincount(ip)) {
250 if (!datasync ||
251 (ip->i_itemp->ili_fields & ~XFS_ILOG_TIMESTAMP))
252 lsn = ip->i_itemp->ili_last_lsn;
253 }
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000254 xfs_iunlock(ip, XFS_ILOCK_SHARED);
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000255
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000256 if (lsn)
Christoph Hellwigb1037052011-09-19 14:55:51 +0000257 error = _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, &log_flushed);
258
Christoph Hellwiga27a2632011-06-16 12:02:23 +0000259 /*
260 * If we only have a single device, and the log force about was
261 * a no-op we might have to flush the data device cache here.
262 * This can only happen for fdatasync/O_DSYNC if we were overwriting
263 * an already allocated file and thus do not have any metadata to
264 * commit.
265 */
266 if ((mp->m_flags & XFS_MOUNT_BARRIER) &&
267 mp->m_logdev_targp == mp->m_ddev_targp &&
268 !XFS_IS_REALTIME_INODE(ip) &&
269 !log_flushed)
270 xfs_blkdev_issue_flush(mp->m_ddev_targp);
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000271
Dave Chinner24513372014-06-25 14:58:08 +1000272 return error;
Christoph Hellwigfd3200b2010-02-15 09:44:48 +0000273}
274
Christoph Hellwig00258e32010-02-15 09:44:47 +0000275STATIC ssize_t
Al Virob4f5d2c2014-04-02 14:37:59 -0400276xfs_file_read_iter(
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000277 struct kiocb *iocb,
Al Virob4f5d2c2014-04-02 14:37:59 -0400278 struct iov_iter *to)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000279{
280 struct file *file = iocb->ki_filp;
281 struct inode *inode = file->f_mapping->host;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000282 struct xfs_inode *ip = XFS_I(inode);
283 struct xfs_mount *mp = ip->i_mount;
Al Virob4f5d2c2014-04-02 14:37:59 -0400284 size_t size = iov_iter_count(to);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000285 ssize_t ret = 0;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000286 int ioflags = 0;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000287 xfs_fsize_t n;
Al Virob4f5d2c2014-04-02 14:37:59 -0400288 loff_t pos = iocb->ki_pos;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000289
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000290 XFS_STATS_INC(xs_read_calls);
291
Al Viro2ba48ce2015-04-09 13:52:01 -0400292 if (unlikely(iocb->ki_flags & IOCB_DIRECT))
Dave Chinnerb92cc59f62014-08-04 13:28:20 +1000293 ioflags |= XFS_IO_ISDIRECT;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000294 if (file->f_mode & FMODE_NOCMTIME)
Dave Chinnerb92cc59f62014-08-04 13:28:20 +1000295 ioflags |= XFS_IO_INVIS;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000296
Dave Chinner6b698ed2015-06-04 09:18:53 +1000297 if ((ioflags & XFS_IO_ISDIRECT) && !IS_DAX(inode)) {
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000298 xfs_buftarg_t *target =
299 XFS_IS_REALTIME_INODE(ip) ?
300 mp->m_rtdev_targp : mp->m_ddev_targp;
Eric Sandeen7c71ee72014-01-21 16:46:23 -0600301 /* DIO must be aligned to device logical sector size */
302 if ((pos | size) & target->bt_logical_sectormask) {
Dave Chinnerfb595812012-11-12 22:53:57 +1100303 if (pos == i_size_read(inode))
Christoph Hellwig00258e32010-02-15 09:44:47 +0000304 return 0;
Eric Sandeenb474c7a2014-06-22 15:04:54 +1000305 return -EINVAL;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000306 }
307 }
308
Dave Chinnerfb595812012-11-12 22:53:57 +1100309 n = mp->m_super->s_maxbytes - pos;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000310 if (n <= 0 || size == 0)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000311 return 0;
312
313 if (n < size)
314 size = n;
315
316 if (XFS_FORCED_SHUTDOWN(mp))
317 return -EIO;
318
Dave Chinner0c38a252011-08-25 07:17:01 +0000319 /*
Brian Foster3d751af2015-08-19 10:35:04 +1000320 * Locking is a bit tricky here. If we take an exclusive lock for direct
321 * IO, we effectively serialise all new concurrent read IO to this file
322 * and block it behind IO that is currently in progress because IO in
323 * progress holds the IO lock shared. We only need to hold the lock
324 * exclusive to blow away the page cache, so only take lock exclusively
325 * if the page cache needs invalidation. This allows the normal direct
326 * IO case of no page cache pages to proceeed concurrently without
327 * serialisation.
Dave Chinner0c38a252011-08-25 07:17:01 +0000328 */
329 xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
Dave Chinnerb92cc59f62014-08-04 13:28:20 +1000330 if ((ioflags & XFS_IO_ISDIRECT) && inode->i_mapping->nrpages) {
Dave Chinner0c38a252011-08-25 07:17:01 +0000331 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
Dave Chinner487f84f2011-01-12 11:37:10 +1100332 xfs_rw_ilock(ip, XFS_IOLOCK_EXCL);
333
Brian Foster3d751af2015-08-19 10:35:04 +1000334 /*
335 * The generic dio code only flushes the range of the particular
336 * I/O. Because we take an exclusive lock here, this whole
337 * sequence is considerably more expensive for us. This has a
338 * noticeable performance impact for any file with cached pages,
339 * even when outside of the range of the particular I/O.
340 *
341 * Hence, amortize the cost of the lock against a full file
342 * flush and reduce the chances of repeated iolock cycles going
343 * forward.
344 */
Christoph Hellwig00258e32010-02-15 09:44:47 +0000345 if (inode->i_mapping->nrpages) {
Brian Foster3d751af2015-08-19 10:35:04 +1000346 ret = filemap_write_and_wait(VFS_I(ip)->i_mapping);
Dave Chinner487f84f2011-01-12 11:37:10 +1100347 if (ret) {
348 xfs_rw_iunlock(ip, XFS_IOLOCK_EXCL);
349 return ret;
350 }
Chris Mason85e584d2014-09-02 12:12:52 +1000351
352 /*
353 * Invalidate whole pages. This can return an error if
354 * we fail to invalidate a page, but this should never
355 * happen on XFS. Warn if it does fail.
356 */
Brian Foster3d751af2015-08-19 10:35:04 +1000357 ret = invalidate_inode_pages2(VFS_I(ip)->i_mapping);
Chris Mason85e584d2014-09-02 12:12:52 +1000358 WARN_ON_ONCE(ret);
359 ret = 0;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000360 }
Dave Chinner487f84f2011-01-12 11:37:10 +1100361 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
Dave Chinner0c38a252011-08-25 07:17:01 +0000362 }
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000363
Dave Chinnerfb595812012-11-12 22:53:57 +1100364 trace_xfs_file_read(ip, size, pos, ioflags);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000365
Al Virob4f5d2c2014-04-02 14:37:59 -0400366 ret = generic_file_read_iter(iocb, to);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000367 if (ret > 0)
368 XFS_STATS_ADD(xs_read_bytes, ret);
369
Dave Chinner487f84f2011-01-12 11:37:10 +1100370 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000371 return ret;
372}
373
Christoph Hellwig00258e32010-02-15 09:44:47 +0000374STATIC ssize_t
375xfs_file_splice_read(
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000376 struct file *infilp,
377 loff_t *ppos,
378 struct pipe_inode_info *pipe,
379 size_t count,
Christoph Hellwig00258e32010-02-15 09:44:47 +0000380 unsigned int flags)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000381{
Christoph Hellwig00258e32010-02-15 09:44:47 +0000382 struct xfs_inode *ip = XFS_I(infilp->f_mapping->host);
Christoph Hellwig00258e32010-02-15 09:44:47 +0000383 int ioflags = 0;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000384 ssize_t ret;
385
386 XFS_STATS_INC(xs_read_calls);
Christoph Hellwig00258e32010-02-15 09:44:47 +0000387
388 if (infilp->f_mode & FMODE_NOCMTIME)
Dave Chinnerb92cc59f62014-08-04 13:28:20 +1000389 ioflags |= XFS_IO_INVIS;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000390
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000391 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
392 return -EIO;
393
Dave Chinner487f84f2011-01-12 11:37:10 +1100394 xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000395
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000396 trace_xfs_file_splice_read(ip, count, *ppos, ioflags);
397
Dave Chinner6b698ed2015-06-04 09:18:53 +1000398 /* for dax, we need to avoid the page cache */
399 if (IS_DAX(VFS_I(ip)))
400 ret = default_file_splice_read(infilp, ppos, pipe, count, flags);
401 else
402 ret = generic_file_splice_read(infilp, ppos, pipe, count, flags);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000403 if (ret > 0)
404 XFS_STATS_ADD(xs_read_bytes, ret);
405
Dave Chinner487f84f2011-01-12 11:37:10 +1100406 xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000407 return ret;
408}
409
Dave Chinner4c5cfd12011-01-11 10:14:16 +1100410/*
Christoph Hellwig193aec12012-03-27 10:34:49 -0400411 * This routine is called to handle zeroing any space in the last block of the
412 * file that is beyond the EOF. We do this since the size is being increased
413 * without writing anything to that block and we don't want to read the
414 * garbage on the disk.
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000415 */
416STATIC int /* error (positive) */
417xfs_zero_last_block(
Christoph Hellwig193aec12012-03-27 10:34:49 -0400418 struct xfs_inode *ip,
419 xfs_fsize_t offset,
Dave Chinner5885ebd2015-02-23 22:37:08 +1100420 xfs_fsize_t isize,
421 bool *did_zeroing)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000422{
Christoph Hellwig193aec12012-03-27 10:34:49 -0400423 struct xfs_mount *mp = ip->i_mount;
424 xfs_fileoff_t last_fsb = XFS_B_TO_FSBT(mp, isize);
425 int zero_offset = XFS_B_FSB_OFFSET(mp, isize);
426 int zero_len;
427 int nimaps = 1;
428 int error = 0;
429 struct xfs_bmbt_irec imap;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000430
Christoph Hellwig193aec12012-03-27 10:34:49 -0400431 xfs_ilock(ip, XFS_ILOCK_EXCL);
Dave Chinner5c8ed202011-09-18 20:40:45 +0000432 error = xfs_bmapi_read(ip, last_fsb, 1, &imap, &nimaps, 0);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400433 xfs_iunlock(ip, XFS_ILOCK_EXCL);
Dave Chinner5c8ed202011-09-18 20:40:45 +0000434 if (error)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000435 return error;
Christoph Hellwig193aec12012-03-27 10:34:49 -0400436
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000437 ASSERT(nimaps > 0);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400438
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000439 /*
440 * If the block underlying isize is just a hole, then there
441 * is nothing to zero.
442 */
Christoph Hellwig193aec12012-03-27 10:34:49 -0400443 if (imap.br_startblock == HOLESTARTBLOCK)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000444 return 0;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000445
446 zero_len = mp->m_sb.sb_blocksize - zero_offset;
447 if (isize + zero_len > offset)
448 zero_len = offset - isize;
Dave Chinner5885ebd2015-02-23 22:37:08 +1100449 *did_zeroing = true;
Christoph Hellwig193aec12012-03-27 10:34:49 -0400450 return xfs_iozero(ip, isize, zero_len);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000451}
452
453/*
Christoph Hellwig193aec12012-03-27 10:34:49 -0400454 * Zero any on disk space between the current EOF and the new, larger EOF.
455 *
456 * This handles the normal case of zeroing the remainder of the last block in
457 * the file and the unusual case of zeroing blocks out beyond the size of the
458 * file. This second case only happens with fixed size extents and when the
459 * system crashes before the inode size was updated but after blocks were
460 * allocated.
461 *
462 * Expects the iolock to be held exclusive, and will take the ilock internally.
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000463 */
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000464int /* error (positive) */
465xfs_zero_eof(
Christoph Hellwig193aec12012-03-27 10:34:49 -0400466 struct xfs_inode *ip,
467 xfs_off_t offset, /* starting I/O offset */
Dave Chinner5885ebd2015-02-23 22:37:08 +1100468 xfs_fsize_t isize, /* current inode size */
469 bool *did_zeroing)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000470{
Christoph Hellwig193aec12012-03-27 10:34:49 -0400471 struct xfs_mount *mp = ip->i_mount;
472 xfs_fileoff_t start_zero_fsb;
473 xfs_fileoff_t end_zero_fsb;
474 xfs_fileoff_t zero_count_fsb;
475 xfs_fileoff_t last_fsb;
476 xfs_fileoff_t zero_off;
477 xfs_fsize_t zero_len;
478 int nimaps;
479 int error = 0;
480 struct xfs_bmbt_irec imap;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000481
Christoph Hellwig193aec12012-03-27 10:34:49 -0400482 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000483 ASSERT(offset > isize);
484
485 /*
486 * First handle zeroing the block on which isize resides.
Christoph Hellwig193aec12012-03-27 10:34:49 -0400487 *
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000488 * We only zero a part of that block so it is handled specially.
489 */
Christoph Hellwig193aec12012-03-27 10:34:49 -0400490 if (XFS_B_FSB_OFFSET(mp, isize) != 0) {
Dave Chinner5885ebd2015-02-23 22:37:08 +1100491 error = xfs_zero_last_block(ip, offset, isize, did_zeroing);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400492 if (error)
493 return error;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000494 }
495
496 /*
Christoph Hellwig193aec12012-03-27 10:34:49 -0400497 * Calculate the range between the new size and the old where blocks
498 * needing to be zeroed may exist.
499 *
500 * To get the block where the last byte in the file currently resides,
501 * we need to subtract one from the size and truncate back to a block
502 * boundary. We subtract 1 in case the size is exactly on a block
503 * boundary.
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000504 */
505 last_fsb = isize ? XFS_B_TO_FSBT(mp, isize - 1) : (xfs_fileoff_t)-1;
506 start_zero_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)isize);
507 end_zero_fsb = XFS_B_TO_FSBT(mp, offset - 1);
508 ASSERT((xfs_sfiloff_t)last_fsb < (xfs_sfiloff_t)start_zero_fsb);
509 if (last_fsb == end_zero_fsb) {
510 /*
511 * The size was only incremented on its last block.
512 * We took care of that above, so just return.
513 */
514 return 0;
515 }
516
517 ASSERT(start_zero_fsb <= end_zero_fsb);
518 while (start_zero_fsb <= end_zero_fsb) {
519 nimaps = 1;
520 zero_count_fsb = end_zero_fsb - start_zero_fsb + 1;
Christoph Hellwig193aec12012-03-27 10:34:49 -0400521
522 xfs_ilock(ip, XFS_ILOCK_EXCL);
Dave Chinner5c8ed202011-09-18 20:40:45 +0000523 error = xfs_bmapi_read(ip, start_zero_fsb, zero_count_fsb,
524 &imap, &nimaps, 0);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400525 xfs_iunlock(ip, XFS_ILOCK_EXCL);
526 if (error)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000527 return error;
Christoph Hellwig193aec12012-03-27 10:34:49 -0400528
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000529 ASSERT(nimaps > 0);
530
531 if (imap.br_state == XFS_EXT_UNWRITTEN ||
532 imap.br_startblock == HOLESTARTBLOCK) {
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000533 start_zero_fsb = imap.br_startoff + imap.br_blockcount;
534 ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
535 continue;
536 }
537
538 /*
539 * There are blocks we need to zero.
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000540 */
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000541 zero_off = XFS_FSB_TO_B(mp, start_zero_fsb);
542 zero_len = XFS_FSB_TO_B(mp, imap.br_blockcount);
543
544 if ((zero_off + zero_len) > offset)
545 zero_len = offset - zero_off;
546
547 error = xfs_iozero(ip, zero_off, zero_len);
Christoph Hellwig193aec12012-03-27 10:34:49 -0400548 if (error)
549 return error;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000550
Dave Chinner5885ebd2015-02-23 22:37:08 +1100551 *did_zeroing = true;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000552 start_zero_fsb = imap.br_startoff + imap.br_blockcount;
553 ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000554 }
555
556 return 0;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000557}
558
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100559/*
Dave Chinner4d8d1582011-01-11 10:23:42 +1100560 * Common pre-write limit and setup checks.
561 *
Christoph Hellwig5bf1f262011-12-18 20:00:13 +0000562 * Called with the iolocked held either shared and exclusive according to
563 * @iolock, and returns with it held. Might upgrade the iolock to exclusive
564 * if called for a direct write beyond i_size.
Dave Chinner4d8d1582011-01-11 10:23:42 +1100565 */
566STATIC ssize_t
567xfs_file_aio_write_checks(
Al Viro99733fa2015-04-07 14:25:18 -0400568 struct kiocb *iocb,
569 struct iov_iter *from,
Dave Chinner4d8d1582011-01-11 10:23:42 +1100570 int *iolock)
571{
Al Viro99733fa2015-04-07 14:25:18 -0400572 struct file *file = iocb->ki_filp;
Dave Chinner4d8d1582011-01-11 10:23:42 +1100573 struct inode *inode = file->f_mapping->host;
574 struct xfs_inode *ip = XFS_I(inode);
Al Viro3309dd02015-04-09 12:55:47 -0400575 ssize_t error = 0;
Al Viro99733fa2015-04-07 14:25:18 -0400576 size_t count = iov_iter_count(from);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100577
Dave Chinner7271d242011-08-25 07:17:02 +0000578restart:
Al Viro3309dd02015-04-09 12:55:47 -0400579 error = generic_write_checks(iocb, from);
580 if (error <= 0)
Dave Chinner4d8d1582011-01-11 10:23:42 +1100581 return error;
Dave Chinner4d8d1582011-01-11 10:23:42 +1100582
Christoph Hellwig21c3ea12015-04-13 11:38:29 +1000583 error = xfs_break_layouts(inode, iolock, true);
Christoph Hellwig781355c2015-02-16 11:59:50 +1100584 if (error)
585 return error;
586
Jan Karaa6de82c2015-05-21 16:05:56 +0200587 /* For changing security info in file_remove_privs() we need i_mutex */
588 if (*iolock == XFS_IOLOCK_SHARED && !IS_NOSEC(inode)) {
589 xfs_rw_iunlock(ip, *iolock);
590 *iolock = XFS_IOLOCK_EXCL;
591 xfs_rw_ilock(ip, *iolock);
592 goto restart;
593 }
Dave Chinner4d8d1582011-01-11 10:23:42 +1100594 /*
595 * If the offset is beyond the size of the file, we need to zero any
596 * blocks that fall between the existing EOF and the start of this
Christoph Hellwig2813d682011-12-18 20:00:12 +0000597 * write. If zeroing is needed and we are currently holding the
Christoph Hellwig467f7892012-03-27 10:34:47 -0400598 * iolock shared, we need to update it to exclusive which implies
599 * having to redo all checks before.
Dave Chinnerb9d59842015-04-16 22:03:07 +1000600 *
601 * We need to serialise against EOF updates that occur in IO
602 * completions here. We want to make sure that nobody is changing the
603 * size while we do this check until we have placed an IO barrier (i.e.
604 * hold the XFS_IOLOCK_EXCL) that prevents new IO from being dispatched.
605 * The spinlock effectively forms a memory barrier once we have the
606 * XFS_IOLOCK_EXCL so we are guaranteed to see the latest EOF value
607 * and hence be able to correctly determine if we need to run zeroing.
Dave Chinner4d8d1582011-01-11 10:23:42 +1100608 */
Dave Chinnerb9d59842015-04-16 22:03:07 +1000609 spin_lock(&ip->i_flags_lock);
Al Viro99733fa2015-04-07 14:25:18 -0400610 if (iocb->ki_pos > i_size_read(inode)) {
Dave Chinner5885ebd2015-02-23 22:37:08 +1100611 bool zero = false;
612
Dave Chinnerb9d59842015-04-16 22:03:07 +1000613 spin_unlock(&ip->i_flags_lock);
Dave Chinner7271d242011-08-25 07:17:02 +0000614 if (*iolock == XFS_IOLOCK_SHARED) {
Christoph Hellwig467f7892012-03-27 10:34:47 -0400615 xfs_rw_iunlock(ip, *iolock);
Dave Chinner7271d242011-08-25 07:17:02 +0000616 *iolock = XFS_IOLOCK_EXCL;
Christoph Hellwig467f7892012-03-27 10:34:47 -0400617 xfs_rw_ilock(ip, *iolock);
Al Viro3309dd02015-04-09 12:55:47 -0400618 iov_iter_reexpand(from, count);
Dave Chinner40c63fb2015-04-16 22:03:17 +1000619
620 /*
621 * We now have an IO submission barrier in place, but
622 * AIO can do EOF updates during IO completion and hence
623 * we now need to wait for all of them to drain. Non-AIO
624 * DIO will have drained before we are given the
625 * XFS_IOLOCK_EXCL, and so for most cases this wait is a
626 * no-op.
627 */
628 inode_dio_wait(inode);
Dave Chinner7271d242011-08-25 07:17:02 +0000629 goto restart;
630 }
Al Viro99733fa2015-04-07 14:25:18 -0400631 error = xfs_zero_eof(ip, iocb->ki_pos, i_size_read(inode), &zero);
Christoph Hellwig467f7892012-03-27 10:34:47 -0400632 if (error)
633 return error;
Dave Chinnerb9d59842015-04-16 22:03:07 +1000634 } else
635 spin_unlock(&ip->i_flags_lock);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100636
637 /*
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000638 * Updating the timestamps will grab the ilock again from
639 * xfs_fs_dirty_inode, so we have to call it after dropping the
640 * lock above. Eventually we should look into a way to avoid
641 * the pointless lock roundtrip.
642 */
Josef Bacikc3b2da32012-03-26 09:59:21 -0400643 if (likely(!(file->f_mode & FMODE_NOCMTIME))) {
644 error = file_update_time(file);
645 if (error)
646 return error;
647 }
Christoph Hellwig8a9c9982012-02-29 09:53:52 +0000648
649 /*
Dave Chinner4d8d1582011-01-11 10:23:42 +1100650 * If we're writing the file then make sure to clear the setuid and
651 * setgid bits if the process is not being run by root. This keeps
652 * people from modifying setuid and setgid binaries.
653 */
Jan Karaa6de82c2015-05-21 16:05:56 +0200654 if (!IS_NOSEC(inode))
655 return file_remove_privs(file);
656 return 0;
Dave Chinner4d8d1582011-01-11 10:23:42 +1100657}
658
659/*
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100660 * xfs_file_dio_aio_write - handle direct IO writes
661 *
662 * Lock the inode appropriately to prepare for and issue a direct IO write.
Dave Chinnereda77982011-01-11 10:22:40 +1100663 * By separating it from the buffered write path we remove all the tricky to
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100664 * follow locking changes and looping.
665 *
Dave Chinnereda77982011-01-11 10:22:40 +1100666 * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
667 * until we're sure the bytes at the new EOF have been zeroed and/or the cached
668 * pages are flushed out.
669 *
670 * In most cases the direct IO writes will be done holding IOLOCK_SHARED
671 * allowing them to be done in parallel with reads and other direct IO writes.
672 * However, if the IO is not aligned to filesystem blocks, the direct IO layer
673 * needs to do sub-block zeroing and that requires serialisation against other
674 * direct IOs to the same block. In this case we need to serialise the
675 * submission of the unaligned IOs so that we don't get racing block zeroing in
676 * the dio layer. To avoid the problem with aio, we also need to wait for
677 * outstanding IOs to complete so that unwritten extent conversion is completed
678 * before we try to map the overlapping block. This is currently implemented by
Christoph Hellwig4a06fd22011-08-23 08:28:13 +0000679 * hitting it with a big hammer (i.e. inode_dio_wait()).
Dave Chinnereda77982011-01-11 10:22:40 +1100680 *
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100681 * Returns with locks held indicated by @iolock and errors indicated by
682 * negative return values.
683 */
684STATIC ssize_t
685xfs_file_dio_aio_write(
686 struct kiocb *iocb,
Al Virob3188912014-04-02 07:06:30 -0400687 struct iov_iter *from)
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100688{
689 struct file *file = iocb->ki_filp;
690 struct address_space *mapping = file->f_mapping;
691 struct inode *inode = mapping->host;
692 struct xfs_inode *ip = XFS_I(inode);
693 struct xfs_mount *mp = ip->i_mount;
694 ssize_t ret = 0;
Dave Chinnereda77982011-01-11 10:22:40 +1100695 int unaligned_io = 0;
Christoph Hellwigd0606462011-12-18 20:00:14 +0000696 int iolock;
Al Virob3188912014-04-02 07:06:30 -0400697 size_t count = iov_iter_count(from);
698 loff_t pos = iocb->ki_pos;
Dave Chinner0cefb292015-04-16 22:03:27 +1000699 loff_t end;
700 struct iov_iter data;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100701 struct xfs_buftarg *target = XFS_IS_REALTIME_INODE(ip) ?
702 mp->m_rtdev_targp : mp->m_ddev_targp;
703
Eric Sandeen7c71ee72014-01-21 16:46:23 -0600704 /* DIO must be aligned to device logical sector size */
Dave Chinner6b698ed2015-06-04 09:18:53 +1000705 if (!IS_DAX(inode) && ((pos | count) & target->bt_logical_sectormask))
Eric Sandeenb474c7a2014-06-22 15:04:54 +1000706 return -EINVAL;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100707
Eric Sandeen7c71ee72014-01-21 16:46:23 -0600708 /* "unaligned" here means not aligned to a filesystem block */
Dave Chinnereda77982011-01-11 10:22:40 +1100709 if ((pos & mp->m_blockmask) || ((pos + count) & mp->m_blockmask))
710 unaligned_io = 1;
711
Dave Chinner7271d242011-08-25 07:17:02 +0000712 /*
713 * We don't need to take an exclusive lock unless there page cache needs
714 * to be invalidated or unaligned IO is being executed. We don't need to
715 * consider the EOF extension case here because
716 * xfs_file_aio_write_checks() will relock the inode as necessary for
717 * EOF zeroing cases and fill out the new inode size as appropriate.
718 */
719 if (unaligned_io || mapping->nrpages)
Christoph Hellwigd0606462011-12-18 20:00:14 +0000720 iolock = XFS_IOLOCK_EXCL;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100721 else
Christoph Hellwigd0606462011-12-18 20:00:14 +0000722 iolock = XFS_IOLOCK_SHARED;
723 xfs_rw_ilock(ip, iolock);
Christoph Hellwigc58cb162011-08-27 14:42:53 +0000724
725 /*
726 * Recheck if there are cached pages that need invalidate after we got
727 * the iolock to protect against other threads adding new pages while
728 * we were waiting for the iolock.
729 */
Christoph Hellwigd0606462011-12-18 20:00:14 +0000730 if (mapping->nrpages && iolock == XFS_IOLOCK_SHARED) {
731 xfs_rw_iunlock(ip, iolock);
732 iolock = XFS_IOLOCK_EXCL;
733 xfs_rw_ilock(ip, iolock);
Christoph Hellwigc58cb162011-08-27 14:42:53 +0000734 }
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100735
Al Viro99733fa2015-04-07 14:25:18 -0400736 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100737 if (ret)
Christoph Hellwigd0606462011-12-18 20:00:14 +0000738 goto out;
Al Viro99733fa2015-04-07 14:25:18 -0400739 count = iov_iter_count(from);
740 pos = iocb->ki_pos;
Dave Chinner0cefb292015-04-16 22:03:27 +1000741 end = pos + count - 1;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100742
Brian Foster3d751af2015-08-19 10:35:04 +1000743 /*
744 * See xfs_file_read_iter() for why we do a full-file flush here.
745 */
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100746 if (mapping->nrpages) {
Brian Foster3d751af2015-08-19 10:35:04 +1000747 ret = filemap_write_and_wait(VFS_I(ip)->i_mapping);
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100748 if (ret)
Christoph Hellwigd0606462011-12-18 20:00:14 +0000749 goto out;
Dave Chinner834ffca2014-09-02 12:12:52 +1000750 /*
Brian Foster3d751af2015-08-19 10:35:04 +1000751 * Invalidate whole pages. This can return an error if we fail
752 * to invalidate a page, but this should never happen on XFS.
753 * Warn if it does fail.
Dave Chinner834ffca2014-09-02 12:12:52 +1000754 */
Brian Foster3d751af2015-08-19 10:35:04 +1000755 ret = invalidate_inode_pages2(VFS_I(ip)->i_mapping);
Dave Chinner834ffca2014-09-02 12:12:52 +1000756 WARN_ON_ONCE(ret);
757 ret = 0;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100758 }
759
Dave Chinnereda77982011-01-11 10:22:40 +1100760 /*
761 * If we are doing unaligned IO, wait for all other IO to drain,
762 * otherwise demote the lock if we had to flush cached pages
763 */
764 if (unaligned_io)
Christoph Hellwig4a06fd22011-08-23 08:28:13 +0000765 inode_dio_wait(inode);
Christoph Hellwigd0606462011-12-18 20:00:14 +0000766 else if (iolock == XFS_IOLOCK_EXCL) {
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100767 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
Christoph Hellwigd0606462011-12-18 20:00:14 +0000768 iolock = XFS_IOLOCK_SHARED;
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100769 }
770
771 trace_xfs_file_direct_write(ip, count, iocb->ki_pos, 0);
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100772
Dave Chinner0cefb292015-04-16 22:03:27 +1000773 data = *from;
Linus Torvalds1aef8822015-04-24 07:08:41 -0700774 ret = mapping->a_ops->direct_IO(iocb, &data, pos);
Dave Chinner0cefb292015-04-16 22:03:27 +1000775
776 /* see generic_file_direct_write() for why this is necessary */
777 if (mapping->nrpages) {
778 invalidate_inode_pages2_range(mapping,
779 pos >> PAGE_CACHE_SHIFT,
780 end >> PAGE_CACHE_SHIFT);
781 }
782
783 if (ret > 0) {
784 pos += ret;
785 iov_iter_advance(from, ret);
786 iocb->ki_pos = pos;
787 }
Christoph Hellwigd0606462011-12-18 20:00:14 +0000788out:
789 xfs_rw_iunlock(ip, iolock);
790
Dave Chinner6b698ed2015-06-04 09:18:53 +1000791 /*
792 * No fallback to buffered IO on errors for XFS. DAX can result in
793 * partial writes, but direct IO will either complete fully or fail.
794 */
795 ASSERT(ret < 0 || ret == count || IS_DAX(VFS_I(ip)));
Dave Chinnerf0d26e82011-01-11 10:15:36 +1100796 return ret;
797}
798
Christoph Hellwig00258e32010-02-15 09:44:47 +0000799STATIC ssize_t
Dave Chinner637bbc72011-01-11 10:17:30 +1100800xfs_file_buffered_aio_write(
801 struct kiocb *iocb,
Al Virob3188912014-04-02 07:06:30 -0400802 struct iov_iter *from)
Dave Chinner637bbc72011-01-11 10:17:30 +1100803{
804 struct file *file = iocb->ki_filp;
805 struct address_space *mapping = file->f_mapping;
806 struct inode *inode = mapping->host;
807 struct xfs_inode *ip = XFS_I(inode);
808 ssize_t ret;
809 int enospc = 0;
Christoph Hellwigd0606462011-12-18 20:00:14 +0000810 int iolock = XFS_IOLOCK_EXCL;
Dave Chinner637bbc72011-01-11 10:17:30 +1100811
Christoph Hellwigd0606462011-12-18 20:00:14 +0000812 xfs_rw_ilock(ip, iolock);
Dave Chinner637bbc72011-01-11 10:17:30 +1100813
Al Viro99733fa2015-04-07 14:25:18 -0400814 ret = xfs_file_aio_write_checks(iocb, from, &iolock);
Dave Chinner4d8d1582011-01-11 10:23:42 +1100815 if (ret)
Christoph Hellwigd0606462011-12-18 20:00:14 +0000816 goto out;
Dave Chinner637bbc72011-01-11 10:17:30 +1100817
818 /* We can write back this queue in page reclaim */
Christoph Hellwigde1414a2015-01-14 10:42:36 +0100819 current->backing_dev_info = inode_to_bdi(inode);
Dave Chinner637bbc72011-01-11 10:17:30 +1100820
821write_retry:
Al Viro99733fa2015-04-07 14:25:18 -0400822 trace_xfs_file_buffered_write(ip, iov_iter_count(from),
823 iocb->ki_pos, 0);
824 ret = generic_perform_write(file, from, iocb->ki_pos);
Al Viro0a64bc22014-02-11 22:25:22 -0500825 if (likely(ret >= 0))
Al Viro99733fa2015-04-07 14:25:18 -0400826 iocb->ki_pos += ret;
Brian Fosterdc06f3982014-07-24 19:49:28 +1000827
Dave Chinner637bbc72011-01-11 10:17:30 +1100828 /*
Brian Fosterdc06f3982014-07-24 19:49:28 +1000829 * If we hit a space limit, try to free up some lingering preallocated
830 * space before returning an error. In the case of ENOSPC, first try to
831 * write back all dirty inodes to free up some of the excess reserved
832 * metadata space. This reduces the chances that the eofblocks scan
833 * waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
834 * also behaves as a filter to prevent too many eofblocks scans from
835 * running at the same time.
Dave Chinner637bbc72011-01-11 10:17:30 +1100836 */
Brian Fosterdc06f3982014-07-24 19:49:28 +1000837 if (ret == -EDQUOT && !enospc) {
838 enospc = xfs_inode_free_quota_eofblocks(ip);
839 if (enospc)
840 goto write_retry;
841 } else if (ret == -ENOSPC && !enospc) {
842 struct xfs_eofblocks eofb = {0};
843
Dave Chinner637bbc72011-01-11 10:17:30 +1100844 enospc = 1;
Dave Chinner9aa05002012-10-08 21:56:04 +1100845 xfs_flush_inodes(ip->i_mount);
Brian Fosterdc06f3982014-07-24 19:49:28 +1000846 eofb.eof_scan_owner = ip->i_ino; /* for locking */
847 eofb.eof_flags = XFS_EOF_FLAGS_SYNC;
848 xfs_icache_free_eofblocks(ip->i_mount, &eofb);
Dave Chinner9aa05002012-10-08 21:56:04 +1100849 goto write_retry;
Dave Chinner637bbc72011-01-11 10:17:30 +1100850 }
Christoph Hellwigd0606462011-12-18 20:00:14 +0000851
Dave Chinner637bbc72011-01-11 10:17:30 +1100852 current->backing_dev_info = NULL;
Christoph Hellwigd0606462011-12-18 20:00:14 +0000853out:
854 xfs_rw_iunlock(ip, iolock);
Dave Chinner637bbc72011-01-11 10:17:30 +1100855 return ret;
856}
857
858STATIC ssize_t
Al Virobf97f3bc2014-04-03 14:20:23 -0400859xfs_file_write_iter(
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000860 struct kiocb *iocb,
Al Virobf97f3bc2014-04-03 14:20:23 -0400861 struct iov_iter *from)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000862{
863 struct file *file = iocb->ki_filp;
864 struct address_space *mapping = file->f_mapping;
865 struct inode *inode = mapping->host;
Christoph Hellwig00258e32010-02-15 09:44:47 +0000866 struct xfs_inode *ip = XFS_I(inode);
Dave Chinner637bbc72011-01-11 10:17:30 +1100867 ssize_t ret;
Al Virobf97f3bc2014-04-03 14:20:23 -0400868 size_t ocount = iov_iter_count(from);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000869
870 XFS_STATS_INC(xs_write_calls);
871
Dave Chinner637bbc72011-01-11 10:17:30 +1100872 if (ocount == 0)
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000873 return 0;
874
Al Virobf97f3bc2014-04-03 14:20:23 -0400875 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
876 return -EIO;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000877
Dave Chinner6b698ed2015-06-04 09:18:53 +1000878 if ((iocb->ki_flags & IOCB_DIRECT) || IS_DAX(inode))
Al Virobf97f3bc2014-04-03 14:20:23 -0400879 ret = xfs_file_dio_aio_write(iocb, from);
Dave Chinner637bbc72011-01-11 10:17:30 +1100880 else
Al Virobf97f3bc2014-04-03 14:20:23 -0400881 ret = xfs_file_buffered_aio_write(iocb, from);
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000882
Christoph Hellwigd0606462011-12-18 20:00:14 +0000883 if (ret > 0) {
884 ssize_t err;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000885
Christoph Hellwigd0606462011-12-18 20:00:14 +0000886 XFS_STATS_ADD(xs_write_bytes, ret);
Christoph Hellwigce7ae1512011-12-18 20:00:11 +0000887
Christoph Hellwigd0606462011-12-18 20:00:14 +0000888 /* Handle various SYNC-type writes */
Al Virod311d792014-02-09 15:18:09 -0500889 err = generic_write_sync(file, iocb->ki_pos - ret, ret);
Christoph Hellwigd0606462011-12-18 20:00:14 +0000890 if (err < 0)
891 ret = err;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000892 }
Dave Chinnera363f0c2011-01-11 10:13:53 +1100893 return ret;
Christoph Hellwigdda35b82010-02-15 09:44:46 +0000894}
895
Namjae Jeona904b1c2015-03-25 15:08:56 +1100896#define XFS_FALLOC_FL_SUPPORTED \
897 (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
898 FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
899 FALLOC_FL_INSERT_RANGE)
900
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100901STATIC long
902xfs_file_fallocate(
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700903 struct file *file,
904 int mode,
905 loff_t offset,
906 loff_t len)
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100907{
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700908 struct inode *inode = file_inode(file);
909 struct xfs_inode *ip = XFS_I(inode);
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700910 long error;
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100911 enum xfs_prealloc_flags flags = 0;
Christoph Hellwig781355c2015-02-16 11:59:50 +1100912 uint iolock = XFS_IOLOCK_EXCL;
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700913 loff_t new_size = 0;
Namjae Jeona904b1c2015-03-25 15:08:56 +1100914 bool do_file_insert = 0;
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100915
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700916 if (!S_ISREG(inode->i_mode))
917 return -EINVAL;
Namjae Jeona904b1c2015-03-25 15:08:56 +1100918 if (mode & ~XFS_FALLOC_FL_SUPPORTED)
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100919 return -EOPNOTSUPP;
920
Christoph Hellwig781355c2015-02-16 11:59:50 +1100921 xfs_ilock(ip, iolock);
Christoph Hellwig21c3ea12015-04-13 11:38:29 +1000922 error = xfs_break_layouts(inode, &iolock, false);
Christoph Hellwig781355c2015-02-16 11:59:50 +1100923 if (error)
924 goto out_unlock;
925
Dave Chinnere8e9ad42015-02-23 21:45:32 +1100926 xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
927 iolock |= XFS_MMAPLOCK_EXCL;
928
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700929 if (mode & FALLOC_FL_PUNCH_HOLE) {
930 error = xfs_free_file_space(ip, offset, len);
931 if (error)
932 goto out_unlock;
Namjae Jeone1d8fb82014-02-24 10:58:19 +1100933 } else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
934 unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
935
936 if (offset & blksize_mask || len & blksize_mask) {
Dave Chinner24513372014-06-25 14:58:08 +1000937 error = -EINVAL;
Namjae Jeone1d8fb82014-02-24 10:58:19 +1100938 goto out_unlock;
939 }
940
Lukas Czerner23fffa92014-04-12 09:56:41 -0400941 /*
942 * There is no need to overlap collapse range with EOF,
943 * in which case it is effectively a truncate operation
944 */
945 if (offset + len >= i_size_read(inode)) {
Dave Chinner24513372014-06-25 14:58:08 +1000946 error = -EINVAL;
Lukas Czerner23fffa92014-04-12 09:56:41 -0400947 goto out_unlock;
948 }
949
Namjae Jeone1d8fb82014-02-24 10:58:19 +1100950 new_size = i_size_read(inode) - len;
951
952 error = xfs_collapse_file_space(ip, offset, len);
953 if (error)
954 goto out_unlock;
Namjae Jeona904b1c2015-03-25 15:08:56 +1100955 } else if (mode & FALLOC_FL_INSERT_RANGE) {
956 unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
957
958 new_size = i_size_read(inode) + len;
959 if (offset & blksize_mask || len & blksize_mask) {
960 error = -EINVAL;
961 goto out_unlock;
962 }
963
964 /* check the new inode size does not wrap through zero */
965 if (new_size > inode->i_sb->s_maxbytes) {
966 error = -EFBIG;
967 goto out_unlock;
968 }
969
970 /* Offset should be less than i_size */
971 if (offset >= i_size_read(inode)) {
972 error = -EINVAL;
973 goto out_unlock;
974 }
975 do_file_insert = 1;
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700976 } else {
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100977 flags |= XFS_PREALLOC_SET;
978
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700979 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
980 offset + len > i_size_read(inode)) {
981 new_size = offset + len;
Dave Chinner24513372014-06-25 14:58:08 +1000982 error = inode_newsize_ok(inode, new_size);
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700983 if (error)
984 goto out_unlock;
985 }
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100986
Lukas Czerner376ba312014-03-13 19:07:58 +1100987 if (mode & FALLOC_FL_ZERO_RANGE)
988 error = xfs_zero_file_space(ip, offset, len);
989 else
990 error = xfs_alloc_file_space(ip, offset, len,
991 XFS_BMAPI_PREALLOC);
Christoph Hellwig2fe17c12011-01-14 13:07:43 +0100992 if (error)
993 goto out_unlock;
994 }
995
Christoph Hellwig83aee9e2013-10-12 00:55:07 -0700996 if (file->f_flags & O_DSYNC)
Christoph Hellwig8add71c2015-02-02 09:53:56 +1100997 flags |= XFS_PREALLOC_SYNC;
998
999 error = xfs_update_prealloc_flags(ip, flags);
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001000 if (error)
1001 goto out_unlock;
1002
1003 /* Change file size if needed */
1004 if (new_size) {
1005 struct iattr iattr;
1006
1007 iattr.ia_valid = ATTR_SIZE;
1008 iattr.ia_size = new_size;
Christoph Hellwig83aee9e2013-10-12 00:55:07 -07001009 error = xfs_setattr_size(ip, &iattr);
Namjae Jeona904b1c2015-03-25 15:08:56 +11001010 if (error)
1011 goto out_unlock;
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001012 }
1013
Namjae Jeona904b1c2015-03-25 15:08:56 +11001014 /*
1015 * Perform hole insertion now that the file size has been
1016 * updated so that if we crash during the operation we don't
1017 * leave shifted extents past EOF and hence losing access to
1018 * the data that is contained within them.
1019 */
1020 if (do_file_insert)
1021 error = xfs_insert_file_space(ip, offset, len);
1022
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001023out_unlock:
Christoph Hellwig781355c2015-02-16 11:59:50 +11001024 xfs_iunlock(ip, iolock);
Dave Chinner24513372014-06-25 14:58:08 +10001025 return error;
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001026}
1027
1028
Linus Torvalds1da177e2005-04-16 15:20:36 -07001029STATIC int
Nathan Scott3562fd42006-03-14 14:00:35 +11001030xfs_file_open(
Linus Torvalds1da177e2005-04-16 15:20:36 -07001031 struct inode *inode,
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001032 struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033{
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001034 if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035 return -EFBIG;
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001036 if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
1037 return -EIO;
1038 return 0;
1039}
1040
1041STATIC int
1042xfs_dir_open(
1043 struct inode *inode,
1044 struct file *file)
1045{
1046 struct xfs_inode *ip = XFS_I(inode);
1047 int mode;
1048 int error;
1049
1050 error = xfs_file_open(inode, file);
1051 if (error)
1052 return error;
1053
1054 /*
1055 * If there are any blocks, read-ahead block 0 as we're almost
1056 * certain to have the next operation be a read there.
1057 */
Christoph Hellwig309ecac2013-12-06 12:30:09 -08001058 mode = xfs_ilock_data_map_shared(ip);
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001059 if (ip->i_d.di_nextents > 0)
Eric Sandeen9df2dd02014-04-14 19:01:59 +10001060 xfs_dir3_data_readahead(ip, 0, -1);
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001061 xfs_iunlock(ip, mode);
1062 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001063}
1064
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065STATIC int
Nathan Scott3562fd42006-03-14 14:00:35 +11001066xfs_file_release(
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067 struct inode *inode,
1068 struct file *filp)
1069{
Dave Chinner24513372014-06-25 14:58:08 +10001070 return xfs_release(XFS_I(inode));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001071}
1072
Linus Torvalds1da177e2005-04-16 15:20:36 -07001073STATIC int
Nathan Scott3562fd42006-03-14 14:00:35 +11001074xfs_file_readdir(
Al Virob8227552013-05-22 17:07:56 -04001075 struct file *file,
1076 struct dir_context *ctx)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077{
Al Virob8227552013-05-22 17:07:56 -04001078 struct inode *inode = file_inode(file);
Christoph Hellwig739bfb22007-08-29 10:58:01 +10001079 xfs_inode_t *ip = XFS_I(inode);
Christoph Hellwig051e7cd2007-08-28 13:58:24 +10001080 size_t bufsize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081
Christoph Hellwig051e7cd2007-08-28 13:58:24 +10001082 /*
1083 * The Linux API doesn't pass down the total size of the buffer
1084 * we read into down to the filesystem. With the filldir concept
1085 * it's not needed for correct information, but the XFS dir2 leaf
1086 * code wants an estimate of the buffer size to calculate it's
1087 * readahead window and size the buffers used for mapping to
1088 * physical blocks.
1089 *
1090 * Try to give it an estimate that's good enough, maybe at some
1091 * point we can change the ->readdir prototype to include the
Eric Sandeena9cc7992010-02-03 17:50:13 +00001092 * buffer size. For now we use the current glibc buffer size.
Christoph Hellwig051e7cd2007-08-28 13:58:24 +10001093 */
Eric Sandeena9cc7992010-02-03 17:50:13 +00001094 bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001095
kbuild test robot83004752014-12-01 08:25:28 +11001096 return xfs_readdir(ip, ctx, bufsize);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097}
1098
David Chinner4f57dbc2007-07-19 16:28:17 +10001099/*
Jeff Liud126d432012-08-21 17:11:57 +08001100 * This type is designed to indicate the type of offset we would like
Eric Sandeen49c69592014-09-09 11:56:48 +10001101 * to search from page cache for xfs_seek_hole_data().
Jeff Liud126d432012-08-21 17:11:57 +08001102 */
1103enum {
1104 HOLE_OFF = 0,
1105 DATA_OFF,
1106};
1107
1108/*
1109 * Lookup the desired type of offset from the given page.
1110 *
1111 * On success, return true and the offset argument will point to the
1112 * start of the region that was found. Otherwise this function will
1113 * return false and keep the offset argument unchanged.
1114 */
1115STATIC bool
1116xfs_lookup_buffer_offset(
1117 struct page *page,
1118 loff_t *offset,
1119 unsigned int type)
1120{
1121 loff_t lastoff = page_offset(page);
1122 bool found = false;
1123 struct buffer_head *bh, *head;
1124
1125 bh = head = page_buffers(page);
1126 do {
1127 /*
1128 * Unwritten extents that have data in the page
1129 * cache covering them can be identified by the
1130 * BH_Unwritten state flag. Pages with multiple
1131 * buffers might have a mix of holes, data and
1132 * unwritten extents - any buffer with valid
1133 * data in it should have BH_Uptodate flag set
1134 * on it.
1135 */
1136 if (buffer_unwritten(bh) ||
1137 buffer_uptodate(bh)) {
1138 if (type == DATA_OFF)
1139 found = true;
1140 } else {
1141 if (type == HOLE_OFF)
1142 found = true;
1143 }
1144
1145 if (found) {
1146 *offset = lastoff;
1147 break;
1148 }
1149 lastoff += bh->b_size;
1150 } while ((bh = bh->b_this_page) != head);
1151
1152 return found;
1153}
1154
1155/*
1156 * This routine is called to find out and return a data or hole offset
1157 * from the page cache for unwritten extents according to the desired
Eric Sandeen49c69592014-09-09 11:56:48 +10001158 * type for xfs_seek_hole_data().
Jeff Liud126d432012-08-21 17:11:57 +08001159 *
1160 * The argument offset is used to tell where we start to search from the
1161 * page cache. Map is used to figure out the end points of the range to
1162 * lookup pages.
1163 *
1164 * Return true if the desired type of offset was found, and the argument
1165 * offset is filled with that address. Otherwise, return false and keep
1166 * offset unchanged.
1167 */
1168STATIC bool
1169xfs_find_get_desired_pgoff(
1170 struct inode *inode,
1171 struct xfs_bmbt_irec *map,
1172 unsigned int type,
1173 loff_t *offset)
1174{
1175 struct xfs_inode *ip = XFS_I(inode);
1176 struct xfs_mount *mp = ip->i_mount;
1177 struct pagevec pvec;
1178 pgoff_t index;
1179 pgoff_t end;
1180 loff_t endoff;
1181 loff_t startoff = *offset;
1182 loff_t lastoff = startoff;
1183 bool found = false;
1184
1185 pagevec_init(&pvec, 0);
1186
1187 index = startoff >> PAGE_CACHE_SHIFT;
1188 endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
1189 end = endoff >> PAGE_CACHE_SHIFT;
1190 do {
1191 int want;
1192 unsigned nr_pages;
1193 unsigned int i;
1194
1195 want = min_t(pgoff_t, end - index, PAGEVEC_SIZE);
1196 nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
1197 want);
1198 /*
1199 * No page mapped into given range. If we are searching holes
1200 * and if this is the first time we got into the loop, it means
1201 * that the given offset is landed in a hole, return it.
1202 *
1203 * If we have already stepped through some block buffers to find
1204 * holes but they all contains data. In this case, the last
1205 * offset is already updated and pointed to the end of the last
1206 * mapped page, if it does not reach the endpoint to search,
1207 * that means there should be a hole between them.
1208 */
1209 if (nr_pages == 0) {
1210 /* Data search found nothing */
1211 if (type == DATA_OFF)
1212 break;
1213
1214 ASSERT(type == HOLE_OFF);
1215 if (lastoff == startoff || lastoff < endoff) {
1216 found = true;
1217 *offset = lastoff;
1218 }
1219 break;
1220 }
1221
1222 /*
1223 * At lease we found one page. If this is the first time we
1224 * step into the loop, and if the first page index offset is
1225 * greater than the given search offset, a hole was found.
1226 */
1227 if (type == HOLE_OFF && lastoff == startoff &&
1228 lastoff < page_offset(pvec.pages[0])) {
1229 found = true;
1230 break;
1231 }
1232
1233 for (i = 0; i < nr_pages; i++) {
1234 struct page *page = pvec.pages[i];
1235 loff_t b_offset;
1236
1237 /*
1238 * At this point, the page may be truncated or
1239 * invalidated (changing page->mapping to NULL),
1240 * or even swizzled back from swapper_space to tmpfs
1241 * file mapping. However, page->index will not change
1242 * because we have a reference on the page.
1243 *
1244 * Searching done if the page index is out of range.
1245 * If the current offset is not reaches the end of
1246 * the specified search range, there should be a hole
1247 * between them.
1248 */
1249 if (page->index > end) {
1250 if (type == HOLE_OFF && lastoff < endoff) {
1251 *offset = lastoff;
1252 found = true;
1253 }
1254 goto out;
1255 }
1256
1257 lock_page(page);
1258 /*
1259 * Page truncated or invalidated(page->mapping == NULL).
1260 * We can freely skip it and proceed to check the next
1261 * page.
1262 */
1263 if (unlikely(page->mapping != inode->i_mapping)) {
1264 unlock_page(page);
1265 continue;
1266 }
1267
1268 if (!page_has_buffers(page)) {
1269 unlock_page(page);
1270 continue;
1271 }
1272
1273 found = xfs_lookup_buffer_offset(page, &b_offset, type);
1274 if (found) {
1275 /*
1276 * The found offset may be less than the start
1277 * point to search if this is the first time to
1278 * come here.
1279 */
1280 *offset = max_t(loff_t, startoff, b_offset);
1281 unlock_page(page);
1282 goto out;
1283 }
1284
1285 /*
1286 * We either searching data but nothing was found, or
1287 * searching hole but found a data buffer. In either
1288 * case, probably the next page contains the desired
1289 * things, update the last offset to it so.
1290 */
1291 lastoff = page_offset(page) + PAGE_SIZE;
1292 unlock_page(page);
1293 }
1294
1295 /*
1296 * The number of returned pages less than our desired, search
1297 * done. In this case, nothing was found for searching data,
1298 * but we found a hole behind the last offset.
1299 */
1300 if (nr_pages < want) {
1301 if (type == HOLE_OFF) {
1302 *offset = lastoff;
1303 found = true;
1304 }
1305 break;
1306 }
1307
1308 index = pvec.pages[i - 1]->index + 1;
1309 pagevec_release(&pvec);
1310 } while (index <= end);
1311
1312out:
1313 pagevec_release(&pvec);
1314 return found;
1315}
1316
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001317STATIC loff_t
Eric Sandeen49c69592014-09-09 11:56:48 +10001318xfs_seek_hole_data(
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001319 struct file *file,
Eric Sandeen49c69592014-09-09 11:56:48 +10001320 loff_t start,
1321 int whence)
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001322{
1323 struct inode *inode = file->f_mapping->host;
1324 struct xfs_inode *ip = XFS_I(inode);
1325 struct xfs_mount *mp = ip->i_mount;
1326 loff_t uninitialized_var(offset);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001327 xfs_fsize_t isize;
1328 xfs_fileoff_t fsbno;
Jeff Liub686d1f2012-08-21 17:12:18 +08001329 xfs_filblks_t end;
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001330 uint lock;
1331 int error;
1332
1333 if (XFS_FORCED_SHUTDOWN(mp))
Eric Sandeenb474c7a2014-06-22 15:04:54 +10001334 return -EIO;
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001335
Christoph Hellwig309ecac2013-12-06 12:30:09 -08001336 lock = xfs_ilock_data_map_shared(ip);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001337
1338 isize = i_size_read(inode);
1339 if (start >= isize) {
Dave Chinner24513372014-06-25 14:58:08 +10001340 error = -ENXIO;
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001341 goto out_unlock;
1342 }
1343
Eric Sandeen49c69592014-09-09 11:56:48 +10001344 /*
1345 * Try to read extents from the first block indicated
1346 * by fsbno to the end block of the file.
1347 */
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001348 fsbno = XFS_B_TO_FSBT(mp, start);
Jeff Liub686d1f2012-08-21 17:12:18 +08001349 end = XFS_B_TO_FSB(mp, isize);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001350
Jeff Liub686d1f2012-08-21 17:12:18 +08001351 for (;;) {
1352 struct xfs_bmbt_irec map[2];
1353 int nmap = 2;
1354 unsigned int i;
1355
1356 error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap,
1357 XFS_BMAPI_ENTIRE);
1358 if (error)
1359 goto out_unlock;
1360
1361 /* No extents at given offset, must be beyond EOF */
1362 if (nmap == 0) {
Dave Chinner24513372014-06-25 14:58:08 +10001363 error = -ENXIO;
Jeff Liub686d1f2012-08-21 17:12:18 +08001364 goto out_unlock;
1365 }
1366
1367 for (i = 0; i < nmap; i++) {
1368 offset = max_t(loff_t, start,
1369 XFS_FSB_TO_B(mp, map[i].br_startoff));
1370
Eric Sandeen49c69592014-09-09 11:56:48 +10001371 /* Landed in the hole we wanted? */
1372 if (whence == SEEK_HOLE &&
1373 map[i].br_startblock == HOLESTARTBLOCK)
1374 goto out;
1375
1376 /* Landed in the data extent we wanted? */
1377 if (whence == SEEK_DATA &&
1378 (map[i].br_startblock == DELAYSTARTBLOCK ||
1379 (map[i].br_state == XFS_EXT_NORM &&
1380 !isnullstartblock(map[i].br_startblock))))
Jeff Liub686d1f2012-08-21 17:12:18 +08001381 goto out;
1382
1383 /*
Eric Sandeen49c69592014-09-09 11:56:48 +10001384 * Landed in an unwritten extent, try to search
1385 * for hole or data from page cache.
Jeff Liub686d1f2012-08-21 17:12:18 +08001386 */
1387 if (map[i].br_state == XFS_EXT_UNWRITTEN) {
1388 if (xfs_find_get_desired_pgoff(inode, &map[i],
Eric Sandeen49c69592014-09-09 11:56:48 +10001389 whence == SEEK_HOLE ? HOLE_OFF : DATA_OFF,
1390 &offset))
Jeff Liub686d1f2012-08-21 17:12:18 +08001391 goto out;
1392 }
1393 }
1394
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001395 /*
Eric Sandeen49c69592014-09-09 11:56:48 +10001396 * We only received one extent out of the two requested. This
1397 * means we've hit EOF and didn't find what we are looking for.
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001398 */
Jeff Liub686d1f2012-08-21 17:12:18 +08001399 if (nmap == 1) {
Eric Sandeen49c69592014-09-09 11:56:48 +10001400 /*
1401 * If we were looking for a hole, set offset to
1402 * the end of the file (i.e., there is an implicit
1403 * hole at the end of any file).
1404 */
1405 if (whence == SEEK_HOLE) {
1406 offset = isize;
1407 break;
1408 }
1409 /*
1410 * If we were looking for data, it's nowhere to be found
1411 */
1412 ASSERT(whence == SEEK_DATA);
1413 error = -ENXIO;
1414 goto out_unlock;
Jeff Liub686d1f2012-08-21 17:12:18 +08001415 }
1416
1417 ASSERT(i > 1);
1418
1419 /*
Eric Sandeen49c69592014-09-09 11:56:48 +10001420 * Nothing was found, proceed to the next round of search
1421 * if the next reading offset is not at or beyond EOF.
Jeff Liub686d1f2012-08-21 17:12:18 +08001422 */
1423 fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount;
1424 start = XFS_FSB_TO_B(mp, fsbno);
1425 if (start >= isize) {
Eric Sandeen49c69592014-09-09 11:56:48 +10001426 if (whence == SEEK_HOLE) {
1427 offset = isize;
1428 break;
1429 }
1430 ASSERT(whence == SEEK_DATA);
1431 error = -ENXIO;
1432 goto out_unlock;
Jeff Liub686d1f2012-08-21 17:12:18 +08001433 }
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001434 }
1435
Jeff Liub686d1f2012-08-21 17:12:18 +08001436out:
1437 /*
Eric Sandeen49c69592014-09-09 11:56:48 +10001438 * If at this point we have found the hole we wanted, the returned
Jeff Liub686d1f2012-08-21 17:12:18 +08001439 * offset may be bigger than the file size as it may be aligned to
Eric Sandeen49c69592014-09-09 11:56:48 +10001440 * page boundary for unwritten extents. We need to deal with this
Jeff Liub686d1f2012-08-21 17:12:18 +08001441 * situation in particular.
1442 */
Eric Sandeen49c69592014-09-09 11:56:48 +10001443 if (whence == SEEK_HOLE)
1444 offset = min_t(loff_t, offset, isize);
Jie Liu46a1c2c2013-06-25 12:02:13 +08001445 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001446
1447out_unlock:
Christoph Hellwig01f4f322013-12-06 12:30:08 -08001448 xfs_iunlock(ip, lock);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001449
1450 if (error)
Dave Chinner24513372014-06-25 14:58:08 +10001451 return error;
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001452 return offset;
1453}
1454
1455STATIC loff_t
1456xfs_file_llseek(
1457 struct file *file,
1458 loff_t offset,
Eric Sandeen59f9c002014-09-09 11:57:10 +10001459 int whence)
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001460{
Eric Sandeen59f9c002014-09-09 11:57:10 +10001461 switch (whence) {
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001462 case SEEK_END:
1463 case SEEK_CUR:
1464 case SEEK_SET:
Eric Sandeen59f9c002014-09-09 11:57:10 +10001465 return generic_file_llseek(file, offset, whence);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001466 case SEEK_HOLE:
Eric Sandeen49c69592014-09-09 11:56:48 +10001467 case SEEK_DATA:
Eric Sandeen59f9c002014-09-09 11:57:10 +10001468 return xfs_seek_hole_data(file, offset, whence);
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001469 default:
1470 return -EINVAL;
1471 }
1472}
1473
Dave Chinnerde0e8c22015-02-23 21:44:19 +11001474/*
1475 * Locking for serialisation of IO during page faults. This results in a lock
1476 * ordering of:
1477 *
1478 * mmap_sem (MM)
Dave Chinner6b698ed2015-06-04 09:18:53 +10001479 * sb_start_pagefault(vfs, freeze)
1480 * i_mmap_lock (XFS - truncate serialisation)
1481 * page_lock (MM)
1482 * i_lock (XFS - extent map serialisation)
Dave Chinnerde0e8c22015-02-23 21:44:19 +11001483 */
Dave Chinnerde0e8c22015-02-23 21:44:19 +11001484
Dave Chinner075a9242015-02-23 21:44:54 +11001485/*
1486 * mmap()d file has taken write protection fault and is being made writable. We
1487 * can set the page state up correctly for a writable page, which means we can
1488 * do correct delalloc accounting (ENOSPC checking!) and unwritten extent
1489 * mapping.
1490 */
1491STATIC int
1492xfs_filemap_page_mkwrite(
1493 struct vm_area_struct *vma,
1494 struct vm_fault *vmf)
1495{
Dave Chinner6b698ed2015-06-04 09:18:53 +10001496 struct inode *inode = file_inode(vma->vm_file);
Dave Chinnerec56b1f2015-06-04 09:18:18 +10001497 int ret;
Dave Chinner075a9242015-02-23 21:44:54 +11001498
Dave Chinner6b698ed2015-06-04 09:18:53 +10001499 trace_xfs_filemap_page_mkwrite(XFS_I(inode));
Dave Chinner075a9242015-02-23 21:44:54 +11001500
Dave Chinner6b698ed2015-06-04 09:18:53 +10001501 sb_start_pagefault(inode->i_sb);
Dave Chinnerec56b1f2015-06-04 09:18:18 +10001502 file_update_time(vma->vm_file);
Dave Chinner6b698ed2015-06-04 09:18:53 +10001503 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1504
1505 if (IS_DAX(inode)) {
1506 ret = __dax_mkwrite(vma, vmf, xfs_get_blocks_direct,
1507 xfs_end_io_dax_write);
1508 } else {
1509 ret = __block_page_mkwrite(vma, vmf, xfs_get_blocks);
1510 ret = block_page_mkwrite_return(ret);
1511 }
1512
1513 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1514 sb_end_pagefault(inode->i_sb);
1515
1516 return ret;
1517}
1518
1519STATIC int
1520xfs_filemap_fault(
1521 struct vm_area_struct *vma,
1522 struct vm_fault *vmf)
1523{
Dave Chinnerb2442c52015-07-29 11:48:00 +10001524 struct inode *inode = file_inode(vma->vm_file);
Dave Chinner6b698ed2015-06-04 09:18:53 +10001525 int ret;
1526
Dave Chinnerb2442c52015-07-29 11:48:00 +10001527 trace_xfs_filemap_fault(XFS_I(inode));
Dave Chinner6b698ed2015-06-04 09:18:53 +10001528
1529 /* DAX can shortcut the normal fault path on write faults! */
Dave Chinnerb2442c52015-07-29 11:48:00 +10001530 if ((vmf->flags & FAULT_FLAG_WRITE) && IS_DAX(inode))
Dave Chinner6b698ed2015-06-04 09:18:53 +10001531 return xfs_filemap_page_mkwrite(vma, vmf);
Dave Chinner075a9242015-02-23 21:44:54 +11001532
Dave Chinnerb2442c52015-07-29 11:48:00 +10001533 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1534 if (IS_DAX(inode)) {
1535 /*
1536 * we do not want to trigger unwritten extent conversion on read
1537 * faults - that is unnecessary overhead and would also require
1538 * changes to xfs_get_blocks_direct() to map unwritten extent
1539 * ioend for conversion on read-only mappings.
1540 */
1541 ret = __dax_fault(vma, vmf, xfs_get_blocks_direct, NULL);
1542 } else
1543 ret = filemap_fault(vma, vmf);
1544 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
Dave Chinner075a9242015-02-23 21:44:54 +11001545
Dave Chinner6b698ed2015-06-04 09:18:53 +10001546 return ret;
1547}
1548
Matthew Wilcoxacd76e72015-09-08 14:59:06 -07001549STATIC int
1550xfs_filemap_pmd_fault(
1551 struct vm_area_struct *vma,
1552 unsigned long addr,
1553 pmd_t *pmd,
1554 unsigned int flags)
1555{
1556 struct inode *inode = file_inode(vma->vm_file);
1557 struct xfs_inode *ip = XFS_I(inode);
1558 int ret;
1559
1560 if (!IS_DAX(inode))
1561 return VM_FAULT_FALLBACK;
1562
1563 trace_xfs_filemap_pmd_fault(ip);
1564
1565 sb_start_pagefault(inode->i_sb);
1566 file_update_time(vma->vm_file);
1567 xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1568 ret = __dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_direct,
1569 xfs_end_io_dax_write);
1570 xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
1571 sb_end_pagefault(inode->i_sb);
1572
1573 return ret;
1574}
1575
Dave Chinner6b698ed2015-06-04 09:18:53 +10001576static const struct vm_operations_struct xfs_file_vm_ops = {
1577 .fault = xfs_filemap_fault,
Matthew Wilcoxacd76e72015-09-08 14:59:06 -07001578 .pmd_fault = xfs_filemap_pmd_fault,
Dave Chinner6b698ed2015-06-04 09:18:53 +10001579 .map_pages = filemap_map_pages,
1580 .page_mkwrite = xfs_filemap_page_mkwrite,
1581};
1582
1583STATIC int
1584xfs_file_mmap(
1585 struct file *filp,
1586 struct vm_area_struct *vma)
1587{
1588 file_accessed(filp);
1589 vma->vm_ops = &xfs_file_vm_ops;
1590 if (IS_DAX(file_inode(filp)))
Matthew Wilcoxacd76e72015-09-08 14:59:06 -07001591 vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
Dave Chinner6b698ed2015-06-04 09:18:53 +10001592 return 0;
Dave Chinner075a9242015-02-23 21:44:54 +11001593}
1594
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08001595const struct file_operations xfs_file_operations = {
Jeff Liu3fe3e6b2012-05-10 21:29:17 +08001596 .llseek = xfs_file_llseek,
Al Virob4f5d2c2014-04-02 14:37:59 -04001597 .read_iter = xfs_file_read_iter,
Al Virobf97f3bc2014-04-03 14:20:23 -04001598 .write_iter = xfs_file_write_iter,
Nathan Scott1b895842006-03-31 13:08:59 +10001599 .splice_read = xfs_file_splice_read,
Al Viro8d020762014-04-05 04:27:08 -04001600 .splice_write = iter_file_splice_write,
Nathan Scott3562fd42006-03-14 14:00:35 +11001601 .unlocked_ioctl = xfs_file_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001602#ifdef CONFIG_COMPAT
Nathan Scott3562fd42006-03-14 14:00:35 +11001603 .compat_ioctl = xfs_file_compat_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001604#endif
Nathan Scott3562fd42006-03-14 14:00:35 +11001605 .mmap = xfs_file_mmap,
1606 .open = xfs_file_open,
1607 .release = xfs_file_release,
1608 .fsync = xfs_file_fsync,
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001609 .fallocate = xfs_file_fallocate,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001610};
1611
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08001612const struct file_operations xfs_dir_file_operations = {
Christoph Hellwigf999a5b2008-11-28 14:23:32 +11001613 .open = xfs_dir_open,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001614 .read = generic_read_dir,
Al Virob8227552013-05-22 17:07:56 -04001615 .iterate = xfs_file_readdir,
Al Viro59af1582008-08-24 07:24:41 -04001616 .llseek = generic_file_llseek,
Nathan Scott3562fd42006-03-14 14:00:35 +11001617 .unlocked_ioctl = xfs_file_ioctl,
Nathan Scottd3870392005-05-06 06:44:46 -07001618#ifdef CONFIG_COMPAT
Nathan Scott3562fd42006-03-14 14:00:35 +11001619 .compat_ioctl = xfs_file_compat_ioctl,
Nathan Scottd3870392005-05-06 06:44:46 -07001620#endif
Christoph Hellwig1da2f2d2011-10-02 14:25:16 +00001621 .fsync = xfs_dir_fsync,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001622};