4 * Copyright (C) 1992 Rick Sladkey
6 * Changes Copyright (C) 1994 by Florian La Roche
7 * - Do not copy data too often around in the kernel.
8 * - In nfs_file_read the return value of kmalloc wasn't checked.
9 * - Put in a better version of read look-ahead buffering. Original idea
10 * and implementation by Wai S Kok elekokws@ee.nus.sg.
12 * Expire cache on write to a file by Wai S Kok (Oct 1994).
14 * Total rewrite of read side for new NFS buffer cache.. Linus.
16 * nfs regular file handling functions
19 #include <linux/time.h>
20 #include <linux/kernel.h>
21 #include <linux/errno.h>
22 #include <linux/fcntl.h>
23 #include <linux/stat.h>
24 #include <linux/nfs_fs.h>
25 #include <linux/nfs_mount.h>
27 #include <linux/slab.h>
28 #include <linux/pagemap.h>
29 #include <linux/smp_lock.h>
30 #include <linux/aio.h>
32 #include <asm/uaccess.h>
33 #include <asm/system.h>
35 #include "delegation.h"
38 #define NFSDBG_FACILITY NFSDBG_FILE
40 static int nfs_file_open(struct inode
*, struct file
*);
41 static int nfs_file_release(struct inode
*, struct file
*);
42 static loff_t
nfs_file_llseek(struct file
*file
, loff_t offset
, int origin
);
43 static int nfs_file_mmap(struct file
*, struct vm_area_struct
*);
44 static ssize_t
nfs_file_sendfile(struct file
*, loff_t
*, size_t, read_actor_t
, void *);
45 static ssize_t
nfs_file_read(struct kiocb
*, const struct iovec
*iov
,
46 unsigned long nr_segs
, loff_t pos
);
47 static ssize_t
nfs_file_write(struct kiocb
*, const struct iovec
*iov
,
48 unsigned long nr_segs
, loff_t pos
);
49 static int nfs_file_flush(struct file
*, fl_owner_t id
);
50 static int nfs_fsync(struct file
*, struct dentry
*dentry
, int datasync
);
51 static int nfs_check_flags(int flags
);
52 static int nfs_lock(struct file
*filp
, int cmd
, struct file_lock
*fl
);
53 static int nfs_flock(struct file
*filp
, int cmd
, struct file_lock
*fl
);
55 const struct file_operations nfs_file_operations
= {
56 .llseek
= nfs_file_llseek
,
58 .write
= do_sync_write
,
59 .aio_read
= nfs_file_read
,
60 .aio_write
= nfs_file_write
,
61 .mmap
= nfs_file_mmap
,
62 .open
= nfs_file_open
,
63 .flush
= nfs_file_flush
,
64 .release
= nfs_file_release
,
68 .sendfile
= nfs_file_sendfile
,
69 .check_flags
= nfs_check_flags
,
72 const struct inode_operations nfs_file_inode_operations
= {
73 .permission
= nfs_permission
,
74 .getattr
= nfs_getattr
,
75 .setattr
= nfs_setattr
,
79 const struct inode_operations nfs3_file_inode_operations
= {
80 .permission
= nfs_permission
,
81 .getattr
= nfs_getattr
,
82 .setattr
= nfs_setattr
,
83 .listxattr
= nfs3_listxattr
,
84 .getxattr
= nfs3_getxattr
,
85 .setxattr
= nfs3_setxattr
,
86 .removexattr
= nfs3_removexattr
,
88 #endif /* CONFIG_NFS_v3 */
90 /* Hack for future NFS swap support */
92 # define IS_SWAPFILE(inode) (0)
95 static int nfs_check_flags(int flags
)
97 if ((flags
& (O_APPEND
| O_DIRECT
)) == (O_APPEND
| O_DIRECT
))
107 nfs_file_open(struct inode
*inode
, struct file
*filp
)
111 res
= nfs_check_flags(filp
->f_flags
);
115 nfs_inc_stats(inode
, NFSIOS_VFSOPEN
);
117 res
= NFS_PROTO(inode
)->file_open(inode
, filp
);
123 nfs_file_release(struct inode
*inode
, struct file
*filp
)
125 /* Ensure that dirty pages are flushed out with the right creds */
126 if (filp
->f_mode
& FMODE_WRITE
)
127 filemap_fdatawrite(filp
->f_mapping
);
128 nfs_inc_stats(inode
, NFSIOS_VFSRELEASE
);
129 return NFS_PROTO(inode
)->file_release(inode
, filp
);
133 * nfs_revalidate_size - Revalidate the file size
134 * @inode - pointer to inode struct
135 * @file - pointer to struct file
137 * Revalidates the file length. This is basically a wrapper around
138 * nfs_revalidate_inode() that takes into account the fact that we may
139 * have cached writes (in which case we don't care about the server's
140 * idea of what the file length is), or O_DIRECT (in which case we
141 * shouldn't trust the cache).
143 static int nfs_revalidate_file_size(struct inode
*inode
, struct file
*filp
)
145 struct nfs_server
*server
= NFS_SERVER(inode
);
146 struct nfs_inode
*nfsi
= NFS_I(inode
);
148 if (server
->flags
& NFS_MOUNT_NOAC
)
150 if (filp
->f_flags
& O_DIRECT
)
152 if (nfsi
->npages
!= 0)
154 if (!(nfsi
->cache_validity
& NFS_INO_REVAL_PAGECACHE
) && !nfs_attribute_timeout(inode
))
157 return __nfs_revalidate_inode(server
, inode
);
160 static loff_t
nfs_file_llseek(struct file
*filp
, loff_t offset
, int origin
)
162 /* origin == SEEK_END => we must revalidate the cached file length */
163 if (origin
== SEEK_END
) {
164 struct inode
*inode
= filp
->f_mapping
->host
;
165 int retval
= nfs_revalidate_file_size(inode
, filp
);
167 return (loff_t
)retval
;
169 return remote_llseek(filp
, offset
, origin
);
173 * Flush all dirty pages, and check for write errors.
177 nfs_file_flush(struct file
*file
, fl_owner_t id
)
179 struct nfs_open_context
*ctx
= (struct nfs_open_context
*)file
->private_data
;
180 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
183 dfprintk(VFS
, "nfs: flush(%s/%ld)\n", inode
->i_sb
->s_id
, inode
->i_ino
);
185 if ((file
->f_mode
& FMODE_WRITE
) == 0)
187 nfs_inc_stats(inode
, NFSIOS_VFSFLUSH
);
189 /* Ensure that data+attribute caches are up to date after close() */
190 status
= nfs_wb_all(inode
);
195 nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
202 nfs_file_read(struct kiocb
*iocb
, const struct iovec
*iov
,
203 unsigned long nr_segs
, loff_t pos
)
205 struct dentry
* dentry
= iocb
->ki_filp
->f_path
.dentry
;
206 struct inode
* inode
= dentry
->d_inode
;
208 size_t count
= iov_length(iov
, nr_segs
);
210 #ifdef CONFIG_NFS_DIRECTIO
211 if (iocb
->ki_filp
->f_flags
& O_DIRECT
)
212 return nfs_file_direct_read(iocb
, iov
, nr_segs
, pos
);
215 dfprintk(VFS
, "nfs: read(%s/%s, %lu@%lu)\n",
216 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
217 (unsigned long) count
, (unsigned long) pos
);
219 result
= nfs_revalidate_mapping(inode
, iocb
->ki_filp
->f_mapping
);
220 nfs_add_stats(inode
, NFSIOS_NORMALREADBYTES
, count
);
222 result
= generic_file_aio_read(iocb
, iov
, nr_segs
, pos
);
227 nfs_file_sendfile(struct file
*filp
, loff_t
*ppos
, size_t count
,
228 read_actor_t actor
, void *target
)
230 struct dentry
*dentry
= filp
->f_path
.dentry
;
231 struct inode
*inode
= dentry
->d_inode
;
234 dfprintk(VFS
, "nfs: sendfile(%s/%s, %lu@%Lu)\n",
235 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
236 (unsigned long) count
, (unsigned long long) *ppos
);
238 res
= nfs_revalidate_mapping(inode
, filp
->f_mapping
);
240 res
= generic_file_sendfile(filp
, ppos
, count
, actor
, target
);
245 nfs_file_mmap(struct file
* file
, struct vm_area_struct
* vma
)
247 struct dentry
*dentry
= file
->f_path
.dentry
;
248 struct inode
*inode
= dentry
->d_inode
;
251 dfprintk(VFS
, "nfs: mmap(%s/%s)\n",
252 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
254 status
= nfs_revalidate_mapping(inode
, file
->f_mapping
);
256 status
= generic_file_mmap(file
, vma
);
261 * Flush any dirty pages for this process, and check for write errors.
262 * The return status from this call provides a reliable indication of
263 * whether any write errors occurred for this process.
266 nfs_fsync(struct file
*file
, struct dentry
*dentry
, int datasync
)
268 struct nfs_open_context
*ctx
= (struct nfs_open_context
*)file
->private_data
;
269 struct inode
*inode
= dentry
->d_inode
;
272 dfprintk(VFS
, "nfs: fsync(%s/%ld)\n", inode
->i_sb
->s_id
, inode
->i_ino
);
274 nfs_inc_stats(inode
, NFSIOS_VFSFSYNC
);
276 status
= nfs_wb_all(inode
);
286 * This does the "real" work of the write. The generic routine has
287 * allocated the page, locked it, done all the page alignment stuff
288 * calculations etc. Now we should just copy the data from user
289 * space and write it back to the real medium..
291 * If the writer ends up delaying the write, the writer needs to
292 * increment the page use counts until he is done with the page.
294 static int nfs_prepare_write(struct file
*file
, struct page
*page
, unsigned offset
, unsigned to
)
296 return nfs_flush_incompatible(file
, page
);
299 static int nfs_commit_write(struct file
*file
, struct page
*page
, unsigned offset
, unsigned to
)
304 status
= nfs_updatepage(file
, page
, offset
, to
-offset
);
309 static void nfs_invalidate_page(struct page
*page
, unsigned long offset
)
313 /* Cancel any unstarted writes on this page */
314 nfs_wb_page_priority(page
->mapping
->host
, page
, FLUSH_INVALIDATE
);
317 static int nfs_release_page(struct page
*page
, gfp_t gfp
)
319 /* If PagePrivate() is set, then the page is not freeable */
323 static int nfs_launder_page(struct page
*page
)
325 return nfs_wb_page(page
->mapping
->host
, page
);
328 const struct address_space_operations nfs_file_aops
= {
329 .readpage
= nfs_readpage
,
330 .readpages
= nfs_readpages
,
331 .set_page_dirty
= nfs_set_page_dirty
,
332 .writepage
= nfs_writepage
,
333 .writepages
= nfs_writepages
,
334 .prepare_write
= nfs_prepare_write
,
335 .commit_write
= nfs_commit_write
,
336 .invalidatepage
= nfs_invalidate_page
,
337 .releasepage
= nfs_release_page
,
338 #ifdef CONFIG_NFS_DIRECTIO
339 .direct_IO
= nfs_direct_IO
,
341 .launder_page
= nfs_launder_page
,
344 static ssize_t
nfs_file_write(struct kiocb
*iocb
, const struct iovec
*iov
,
345 unsigned long nr_segs
, loff_t pos
)
347 struct dentry
* dentry
= iocb
->ki_filp
->f_path
.dentry
;
348 struct inode
* inode
= dentry
->d_inode
;
350 size_t count
= iov_length(iov
, nr_segs
);
352 #ifdef CONFIG_NFS_DIRECTIO
353 if (iocb
->ki_filp
->f_flags
& O_DIRECT
)
354 return nfs_file_direct_write(iocb
, iov
, nr_segs
, pos
);
357 dfprintk(VFS
, "nfs: write(%s/%s(%ld), %lu@%Ld)\n",
358 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
359 inode
->i_ino
, (unsigned long) count
, (long long) pos
);
362 if (IS_SWAPFILE(inode
))
365 * O_APPEND implies that we must revalidate the file length.
367 if (iocb
->ki_filp
->f_flags
& O_APPEND
) {
368 result
= nfs_revalidate_file_size(inode
, iocb
->ki_filp
);
377 nfs_add_stats(inode
, NFSIOS_NORMALWRITTENBYTES
, count
);
378 result
= generic_file_aio_write(iocb
, iov
, nr_segs
, pos
);
379 /* Return error values for O_SYNC and IS_SYNC() */
380 if (result
>= 0 && (IS_SYNC(inode
) || (iocb
->ki_filp
->f_flags
& O_SYNC
))) {
381 int err
= nfs_fsync(iocb
->ki_filp
, dentry
, 1);
389 printk(KERN_INFO
"NFS: attempt to write to active swap file!\n");
393 static int do_getlk(struct file
*filp
, int cmd
, struct file_lock
*fl
)
395 struct inode
*inode
= filp
->f_mapping
->host
;
399 /* Try local locking first */
400 if (posix_test_lock(filp
, fl
)) {
404 if (nfs_have_delegation(inode
, FMODE_READ
))
407 if (NFS_SERVER(inode
)->flags
& NFS_MOUNT_NONLM
)
410 status
= NFS_PROTO(inode
)->lock(filp
, cmd
, fl
);
415 fl
->fl_type
= F_UNLCK
;
419 static int do_vfs_lock(struct file
*file
, struct file_lock
*fl
)
422 switch (fl
->fl_flags
& (FL_POSIX
|FL_FLOCK
)) {
424 res
= posix_lock_file_wait(file
, fl
);
427 res
= flock_lock_file_wait(file
, fl
);
433 dprintk(KERN_WARNING
"%s: VFS is out of sync with lock manager"
439 static int do_unlk(struct file
*filp
, int cmd
, struct file_lock
*fl
)
441 struct inode
*inode
= filp
->f_mapping
->host
;
445 * Flush all pending writes before doing anything
448 nfs_sync_mapping(filp
->f_mapping
);
450 /* NOTE: special case
451 * If we're signalled while cleaning up locks on process exit, we
452 * still need to complete the unlock.
455 /* Use local locking if mounted with "-onolock" */
456 if (!(NFS_SERVER(inode
)->flags
& NFS_MOUNT_NONLM
))
457 status
= NFS_PROTO(inode
)->lock(filp
, cmd
, fl
);
459 status
= do_vfs_lock(filp
, fl
);
464 static int do_setlk(struct file
*filp
, int cmd
, struct file_lock
*fl
)
466 struct inode
*inode
= filp
->f_mapping
->host
;
470 * Flush all pending writes before doing anything
473 status
= nfs_sync_mapping(filp
->f_mapping
);
478 /* Use local locking if mounted with "-onolock" */
479 if (!(NFS_SERVER(inode
)->flags
& NFS_MOUNT_NONLM
)) {
480 status
= NFS_PROTO(inode
)->lock(filp
, cmd
, fl
);
481 /* If we were signalled we still need to ensure that
482 * we clean up any state on the server. We therefore
483 * record the lock call as having succeeded in order to
484 * ensure that locks_remove_posix() cleans it out when
487 if (status
== -EINTR
|| status
== -ERESTARTSYS
)
488 do_vfs_lock(filp
, fl
);
490 status
= do_vfs_lock(filp
, fl
);
495 * Make sure we clear the cache whenever we try to get the lock.
496 * This makes locking act as a cache coherency point.
498 nfs_sync_mapping(filp
->f_mapping
);
499 nfs_zap_caches(inode
);
505 * Lock a (portion of) a file
507 static int nfs_lock(struct file
*filp
, int cmd
, struct file_lock
*fl
)
509 struct inode
* inode
= filp
->f_mapping
->host
;
511 dprintk("NFS: nfs_lock(f=%s/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n",
512 inode
->i_sb
->s_id
, inode
->i_ino
,
513 fl
->fl_type
, fl
->fl_flags
,
514 (long long)fl
->fl_start
, (long long)fl
->fl_end
);
515 nfs_inc_stats(inode
, NFSIOS_VFSLOCK
);
517 /* No mandatory locks over NFS */
518 if ((inode
->i_mode
& (S_ISGID
| S_IXGRP
)) == S_ISGID
&&
519 fl
->fl_type
!= F_UNLCK
)
523 return do_getlk(filp
, cmd
, fl
);
524 if (fl
->fl_type
== F_UNLCK
)
525 return do_unlk(filp
, cmd
, fl
);
526 return do_setlk(filp
, cmd
, fl
);
530 * Lock a (portion of) a file
532 static int nfs_flock(struct file
*filp
, int cmd
, struct file_lock
*fl
)
534 dprintk("NFS: nfs_flock(f=%s/%ld, t=%x, fl=%x)\n",
535 filp
->f_path
.dentry
->d_inode
->i_sb
->s_id
,
536 filp
->f_path
.dentry
->d_inode
->i_ino
,
537 fl
->fl_type
, fl
->fl_flags
);
540 * No BSD flocks over NFS allowed.
541 * Note: we could try to fake a POSIX lock request here by
542 * using ((u32) filp | 0x80000000) or some such as the pid.
543 * Not sure whether that would be unique, though, or whether
544 * that would break in other places.
546 if (!(fl
->fl_flags
& FL_FLOCK
))
549 /* We're simulating flock() locks using posix locks on the server */
550 fl
->fl_owner
= (fl_owner_t
)filp
;
552 fl
->fl_end
= OFFSET_MAX
;
554 if (fl
->fl_type
== F_UNLCK
)
555 return do_unlk(filp
, cmd
, fl
);
556 return do_setlk(filp
, cmd
, fl
);