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NFS: Make nfs_fsync methods consistent
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CommitLineData
1da177e4
LT
1/*
2 * linux/fs/nfs/file.c
3 *
4 * Copyright (C) 1992 Rick Sladkey
5 *
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.
11 *
12 * Expire cache on write to a file by Wai S Kok (Oct 1994).
13 *
14 * Total rewrite of read side for new NFS buffer cache.. Linus.
15 *
16 * nfs regular file handling functions
17 */
18
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>
26#include <linux/mm.h>
27#include <linux/slab.h>
28#include <linux/pagemap.h>
29#include <linux/smp_lock.h>
e8edc6e0 30#include <linux/aio.h>
1da177e4
LT
31
32#include <asm/uaccess.h>
33#include <asm/system.h>
34
35#include "delegation.h"
94387fb1 36#include "internal.h"
91d5b470 37#include "iostat.h"
1da177e4
LT
38
39#define NFSDBG_FACILITY NFSDBG_FILE
40
41static int nfs_file_open(struct inode *, struct file *);
42static int nfs_file_release(struct inode *, struct file *);
980802e3 43static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin);
1da177e4 44static int nfs_file_mmap(struct file *, struct vm_area_struct *);
f0930fff
JA
45static ssize_t nfs_file_splice_read(struct file *filp, loff_t *ppos,
46 struct pipe_inode_info *pipe,
47 size_t count, unsigned int flags);
027445c3
BP
48static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov,
49 unsigned long nr_segs, loff_t pos);
50static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov,
51 unsigned long nr_segs, loff_t pos);
75e1fcc0 52static int nfs_file_flush(struct file *, fl_owner_t id);
54917786 53static int nfs_file_fsync(struct file *, struct dentry *dentry, int datasync);
1da177e4
LT
54static int nfs_check_flags(int flags);
55static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
56static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
370f6599 57static int nfs_setlease(struct file *file, long arg, struct file_lock **fl);
1da177e4 58
94387fb1
TM
59static struct vm_operations_struct nfs_file_vm_ops;
60
4b6f5d20 61const struct file_operations nfs_file_operations = {
980802e3 62 .llseek = nfs_file_llseek,
1da177e4
LT
63 .read = do_sync_read,
64 .write = do_sync_write,
027445c3
BP
65 .aio_read = nfs_file_read,
66 .aio_write = nfs_file_write,
240ee831 67#ifdef CONFIG_MMU
1da177e4 68 .mmap = nfs_file_mmap,
240ee831
BW
69#else
70 .mmap = generic_file_mmap,
71#endif
1da177e4
LT
72 .open = nfs_file_open,
73 .flush = nfs_file_flush,
74 .release = nfs_file_release,
54917786 75 .fsync = nfs_file_fsync,
1da177e4
LT
76 .lock = nfs_lock,
77 .flock = nfs_flock,
f0930fff 78 .splice_read = nfs_file_splice_read,
1da177e4 79 .check_flags = nfs_check_flags,
370f6599 80 .setlease = nfs_setlease,
1da177e4
LT
81};
82
92e1d5be 83const struct inode_operations nfs_file_inode_operations = {
1da177e4
LT
84 .permission = nfs_permission,
85 .getattr = nfs_getattr,
86 .setattr = nfs_setattr,
87};
88
b7fa0554 89#ifdef CONFIG_NFS_V3
92e1d5be 90const struct inode_operations nfs3_file_inode_operations = {
b7fa0554
AG
91 .permission = nfs_permission,
92 .getattr = nfs_getattr,
93 .setattr = nfs_setattr,
94 .listxattr = nfs3_listxattr,
95 .getxattr = nfs3_getxattr,
96 .setxattr = nfs3_setxattr,
97 .removexattr = nfs3_removexattr,
98};
99#endif /* CONFIG_NFS_v3 */
100
1da177e4
LT
101/* Hack for future NFS swap support */
102#ifndef IS_SWAPFILE
103# define IS_SWAPFILE(inode) (0)
104#endif
105
106static int nfs_check_flags(int flags)
107{
108 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
109 return -EINVAL;
110
111 return 0;
112}
113
114/*
115 * Open file
116 */
117static int
118nfs_file_open(struct inode *inode, struct file *filp)
119{
1da177e4
LT
120 int res;
121
122 res = nfs_check_flags(filp->f_flags);
123 if (res)
124 return res;
125
91d5b470 126 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
1da177e4 127 lock_kernel();
1f163415 128 res = NFS_PROTO(inode)->file_open(inode, filp);
1da177e4
LT
129 unlock_kernel();
130 return res;
131}
132
133static int
134nfs_file_release(struct inode *inode, struct file *filp)
135{
136 /* Ensure that dirty pages are flushed out with the right creds */
137 if (filp->f_mode & FMODE_WRITE)
a49c3c77 138 nfs_wb_all(filp->f_path.dentry->d_inode);
91d5b470 139 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
1da177e4
LT
140 return NFS_PROTO(inode)->file_release(inode, filp);
141}
142
980802e3
TM
143/**
144 * nfs_revalidate_size - Revalidate the file size
145 * @inode - pointer to inode struct
146 * @file - pointer to struct file
147 *
148 * Revalidates the file length. This is basically a wrapper around
149 * nfs_revalidate_inode() that takes into account the fact that we may
150 * have cached writes (in which case we don't care about the server's
151 * idea of what the file length is), or O_DIRECT (in which case we
152 * shouldn't trust the cache).
153 */
154static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
155{
156 struct nfs_server *server = NFS_SERVER(inode);
157 struct nfs_inode *nfsi = NFS_I(inode);
158
159 if (server->flags & NFS_MOUNT_NOAC)
160 goto force_reval;
161 if (filp->f_flags & O_DIRECT)
162 goto force_reval;
163 if (nfsi->npages != 0)
164 return 0;
55296809 165 if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode))
fe51beec 166 return 0;
980802e3
TM
167force_reval:
168 return __nfs_revalidate_inode(server, inode);
169}
170
171static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
172{
173 /* origin == SEEK_END => we must revalidate the cached file length */
aec5e175 174 if (origin == SEEK_END) {
980802e3
TM
175 struct inode *inode = filp->f_mapping->host;
176 int retval = nfs_revalidate_file_size(inode, filp);
177 if (retval < 0)
178 return (loff_t)retval;
179 }
180 return remote_llseek(filp, offset, origin);
181}
182
7b159fc1 183/*
54917786 184 * Helper for nfs_file_flush() and nfs_file_fsync()
7b159fc1
TM
185 *
186 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
187 * disk, but it retrieves and clears ctx->error after synching, despite
188 * the two being set at the same time in nfs_context_set_write_error().
189 * This is because the former is used to notify the _next_ call to
190 * nfs_file_write() that a write error occured, and hence cause it to
191 * fall back to doing a synchronous write.
192 */
193static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode)
194{
195 int have_error, status;
196 int ret = 0;
197
198 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
199 status = nfs_wb_all(inode);
200 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
201 if (have_error)
202 ret = xchg(&ctx->error, 0);
203 if (!ret)
204 ret = status;
205 return ret;
206}
207
1da177e4
LT
208/*
209 * Flush all dirty pages, and check for write errors.
210 *
211 */
212static int
75e1fcc0 213nfs_file_flush(struct file *file, fl_owner_t id)
1da177e4 214{
cd3758e3 215 struct nfs_open_context *ctx = nfs_file_open_context(file);
01cce933 216 struct inode *inode = file->f_path.dentry->d_inode;
1da177e4
LT
217 int status;
218
219 dfprintk(VFS, "nfs: flush(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
220
221 if ((file->f_mode & FMODE_WRITE) == 0)
222 return 0;
91d5b470 223 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
7b159fc1 224
1da177e4 225 /* Ensure that data+attribute caches are up to date after close() */
7b159fc1
TM
226 status = nfs_do_fsync(ctx, inode);
227 if (!status)
228 nfs_revalidate_inode(NFS_SERVER(inode), inode);
1da177e4
LT
229 return status;
230}
231
232static ssize_t
027445c3
BP
233nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
234 unsigned long nr_segs, loff_t pos)
1da177e4 235{
01cce933 236 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
1da177e4
LT
237 struct inode * inode = dentry->d_inode;
238 ssize_t result;
027445c3 239 size_t count = iov_length(iov, nr_segs);
1da177e4 240
1da177e4 241 if (iocb->ki_filp->f_flags & O_DIRECT)
027445c3 242 return nfs_file_direct_read(iocb, iov, nr_segs, pos);
1da177e4
LT
243
244 dfprintk(VFS, "nfs: read(%s/%s, %lu@%lu)\n",
245 dentry->d_parent->d_name.name, dentry->d_name.name,
246 (unsigned long) count, (unsigned long) pos);
247
44b11874 248 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
91d5b470 249 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count);
1da177e4 250 if (!result)
027445c3 251 result = generic_file_aio_read(iocb, iov, nr_segs, pos);
1da177e4
LT
252 return result;
253}
254
255static ssize_t
f0930fff
JA
256nfs_file_splice_read(struct file *filp, loff_t *ppos,
257 struct pipe_inode_info *pipe, size_t count,
258 unsigned int flags)
1da177e4 259{
01cce933 260 struct dentry *dentry = filp->f_path.dentry;
1da177e4
LT
261 struct inode *inode = dentry->d_inode;
262 ssize_t res;
263
f0930fff 264 dfprintk(VFS, "nfs: splice_read(%s/%s, %lu@%Lu)\n",
1da177e4
LT
265 dentry->d_parent->d_name.name, dentry->d_name.name,
266 (unsigned long) count, (unsigned long long) *ppos);
267
44b11874 268 res = nfs_revalidate_mapping(inode, filp->f_mapping);
1da177e4 269 if (!res)
f0930fff 270 res = generic_file_splice_read(filp, ppos, pipe, count, flags);
1da177e4
LT
271 return res;
272}
273
274static int
275nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
276{
01cce933 277 struct dentry *dentry = file->f_path.dentry;
1da177e4
LT
278 struct inode *inode = dentry->d_inode;
279 int status;
280
281 dfprintk(VFS, "nfs: mmap(%s/%s)\n",
282 dentry->d_parent->d_name.name, dentry->d_name.name);
283
44b11874 284 status = nfs_revalidate_mapping(inode, file->f_mapping);
94387fb1
TM
285 if (!status) {
286 vma->vm_ops = &nfs_file_vm_ops;
287 vma->vm_flags |= VM_CAN_NONLINEAR;
288 file_accessed(file);
289 }
1da177e4
LT
290 return status;
291}
292
293/*
294 * Flush any dirty pages for this process, and check for write errors.
295 * The return status from this call provides a reliable indication of
296 * whether any write errors occurred for this process.
297 */
298static int
54917786 299nfs_file_fsync(struct file *file, struct dentry *dentry, int datasync)
1da177e4 300{
cd3758e3 301 struct nfs_open_context *ctx = nfs_file_open_context(file);
1da177e4 302 struct inode *inode = dentry->d_inode;
1da177e4 303
54917786
CL
304 dfprintk(VFS, "NFS: fsync file(%s/%s) datasync %d\n",
305 dentry->d_parent->d_name.name, dentry->d_name.name,
306 datasync);
1da177e4 307
91d5b470 308 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
7b159fc1 309 return nfs_do_fsync(ctx, inode);
1da177e4
LT
310}
311
312/*
4899f9c8
NP
313 * This does the "real" work of the write. We must allocate and lock the
314 * page to be sent back to the generic routine, which then copies the
315 * data from user space.
1da177e4
LT
316 *
317 * If the writer ends up delaying the write, the writer needs to
318 * increment the page use counts until he is done with the page.
319 */
4899f9c8
NP
320static int nfs_write_begin(struct file *file, struct address_space *mapping,
321 loff_t pos, unsigned len, unsigned flags,
322 struct page **pagep, void **fsdata)
1da177e4 323{
4899f9c8
NP
324 int ret;
325 pgoff_t index;
326 struct page *page;
327 index = pos >> PAGE_CACHE_SHIFT;
328
329 page = __grab_cache_page(mapping, index);
330 if (!page)
331 return -ENOMEM;
332 *pagep = page;
333
334 ret = nfs_flush_incompatible(file, page);
335 if (ret) {
336 unlock_page(page);
337 page_cache_release(page);
338 }
339 return ret;
1da177e4
LT
340}
341
4899f9c8
NP
342static int nfs_write_end(struct file *file, struct address_space *mapping,
343 loff_t pos, unsigned len, unsigned copied,
344 struct page *page, void *fsdata)
1da177e4 345{
4899f9c8
NP
346 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
347 int status;
1da177e4 348
efc91ed0
TM
349 /*
350 * Zero any uninitialised parts of the page, and then mark the page
351 * as up to date if it turns out that we're extending the file.
352 */
353 if (!PageUptodate(page)) {
354 unsigned pglen = nfs_page_length(page);
355 unsigned end = offset + len;
356
357 if (pglen == 0) {
358 zero_user_segments(page, 0, offset,
359 end, PAGE_CACHE_SIZE);
360 SetPageUptodate(page);
361 } else if (end >= pglen) {
362 zero_user_segment(page, end, PAGE_CACHE_SIZE);
363 if (offset == 0)
364 SetPageUptodate(page);
365 } else
366 zero_user_segment(page, pglen, PAGE_CACHE_SIZE);
367 }
368
1da177e4 369 lock_kernel();
4899f9c8 370 status = nfs_updatepage(file, page, offset, copied);
1da177e4 371 unlock_kernel();
4899f9c8
NP
372
373 unlock_page(page);
374 page_cache_release(page);
375
3d509e54
CL
376 if (status < 0)
377 return status;
378 return copied;
1da177e4
LT
379}
380
2ff28e22 381static void nfs_invalidate_page(struct page *page, unsigned long offset)
cd52ed35 382{
1c75950b
TM
383 if (offset != 0)
384 return;
d2ccddf0 385 /* Cancel any unstarted writes on this page */
1b3b4a1a 386 nfs_wb_page_cancel(page->mapping->host, page);
cd52ed35
TM
387}
388
389static int nfs_release_page(struct page *page, gfp_t gfp)
390{
e3db7691
TM
391 /* If PagePrivate() is set, then the page is not freeable */
392 return 0;
393}
394
395static int nfs_launder_page(struct page *page)
396{
397 return nfs_wb_page(page->mapping->host, page);
cd52ed35
TM
398}
399
f5e54d6e 400const struct address_space_operations nfs_file_aops = {
1da177e4
LT
401 .readpage = nfs_readpage,
402 .readpages = nfs_readpages,
9cccef95 403 .set_page_dirty = __set_page_dirty_nobuffers,
1da177e4
LT
404 .writepage = nfs_writepage,
405 .writepages = nfs_writepages,
4899f9c8
NP
406 .write_begin = nfs_write_begin,
407 .write_end = nfs_write_end,
cd52ed35
TM
408 .invalidatepage = nfs_invalidate_page,
409 .releasepage = nfs_release_page,
1da177e4 410 .direct_IO = nfs_direct_IO,
e3db7691 411 .launder_page = nfs_launder_page,
1da177e4
LT
412};
413
94387fb1
TM
414static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page)
415{
416 struct file *filp = vma->vm_file;
417 unsigned pagelen;
418 int ret = -EINVAL;
4899f9c8 419 struct address_space *mapping;
94387fb1
TM
420
421 lock_page(page);
4899f9c8 422 mapping = page->mapping;
8b1f9ee5
TM
423 if (mapping != vma->vm_file->f_path.dentry->d_inode->i_mapping)
424 goto out_unlock;
425
426 ret = 0;
94387fb1 427 pagelen = nfs_page_length(page);
8b1f9ee5
TM
428 if (pagelen == 0)
429 goto out_unlock;
4899f9c8 430
8b1f9ee5
TM
431 ret = nfs_flush_incompatible(filp, page);
432 if (ret != 0)
433 goto out_unlock;
434
435 ret = nfs_updatepage(filp, page, 0, pagelen);
436 if (ret == 0)
437 ret = pagelen;
438out_unlock:
439 unlock_page(page);
94387fb1
TM
440 return ret;
441}
442
443static struct vm_operations_struct nfs_file_vm_ops = {
444 .fault = filemap_fault,
445 .page_mkwrite = nfs_vm_page_mkwrite,
446};
447
7b159fc1
TM
448static int nfs_need_sync_write(struct file *filp, struct inode *inode)
449{
450 struct nfs_open_context *ctx;
451
452 if (IS_SYNC(inode) || (filp->f_flags & O_SYNC))
453 return 1;
cd3758e3 454 ctx = nfs_file_open_context(filp);
7b159fc1
TM
455 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags))
456 return 1;
457 return 0;
458}
459
027445c3
BP
460static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov,
461 unsigned long nr_segs, loff_t pos)
1da177e4 462{
01cce933 463 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
1da177e4
LT
464 struct inode * inode = dentry->d_inode;
465 ssize_t result;
027445c3 466 size_t count = iov_length(iov, nr_segs);
1da177e4 467
1da177e4 468 if (iocb->ki_filp->f_flags & O_DIRECT)
027445c3 469 return nfs_file_direct_write(iocb, iov, nr_segs, pos);
1da177e4 470
027445c3 471 dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%Ld)\n",
1da177e4 472 dentry->d_parent->d_name.name, dentry->d_name.name,
027445c3 473 inode->i_ino, (unsigned long) count, (long long) pos);
1da177e4
LT
474
475 result = -EBUSY;
476 if (IS_SWAPFILE(inode))
477 goto out_swapfile;
7d52e862
TM
478 /*
479 * O_APPEND implies that we must revalidate the file length.
480 */
481 if (iocb->ki_filp->f_flags & O_APPEND) {
482 result = nfs_revalidate_file_size(inode, iocb->ki_filp);
483 if (result)
484 goto out;
fe51beec 485 }
1da177e4
LT
486
487 result = count;
488 if (!count)
489 goto out;
490
91d5b470 491 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count);
027445c3 492 result = generic_file_aio_write(iocb, iov, nr_segs, pos);
200baa21 493 /* Return error values for O_SYNC and IS_SYNC() */
7b159fc1 494 if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) {
cd3758e3 495 int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode);
200baa21
TM
496 if (err < 0)
497 result = err;
498 }
1da177e4
LT
499out:
500 return result;
501
502out_swapfile:
503 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
504 goto out;
505}
506
507static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
508{
509 struct inode *inode = filp->f_mapping->host;
510 int status = 0;
511
512 lock_kernel();
039c4d7a 513 /* Try local locking first */
6d34ac19
BF
514 posix_test_lock(filp, fl);
515 if (fl->fl_type != F_UNLCK) {
516 /* found a conflict */
039c4d7a 517 goto out;
1da177e4 518 }
039c4d7a
TM
519
520 if (nfs_have_delegation(inode, FMODE_READ))
521 goto out_noconflict;
522
523 if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)
524 goto out_noconflict;
525
526 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
527out:
1da177e4
LT
528 unlock_kernel();
529 return status;
039c4d7a
TM
530out_noconflict:
531 fl->fl_type = F_UNLCK;
532 goto out;
1da177e4
LT
533}
534
535static int do_vfs_lock(struct file *file, struct file_lock *fl)
536{
537 int res = 0;
538 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
539 case FL_POSIX:
540 res = posix_lock_file_wait(file, fl);
541 break;
542 case FL_FLOCK:
543 res = flock_lock_file_wait(file, fl);
544 break;
545 default:
546 BUG();
547 }
548 if (res < 0)
46bae1a9
NB
549 dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager"
550 " - error %d!\n",
3110ff80 551 __func__, res);
1da177e4
LT
552 return res;
553}
554
555static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
556{
557 struct inode *inode = filp->f_mapping->host;
1da177e4
LT
558 int status;
559
1da177e4
LT
560 /*
561 * Flush all pending writes before doing anything
562 * with locks..
563 */
29884df0 564 nfs_sync_mapping(filp->f_mapping);
1da177e4
LT
565
566 /* NOTE: special case
567 * If we're signalled while cleaning up locks on process exit, we
568 * still need to complete the unlock.
569 */
570 lock_kernel();
571 /* Use local locking if mounted with "-onolock" */
572 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
573 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
574 else
575 status = do_vfs_lock(filp, fl);
576 unlock_kernel();
1da177e4
LT
577 return status;
578}
579
580static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
581{
582 struct inode *inode = filp->f_mapping->host;
1da177e4
LT
583 int status;
584
1da177e4
LT
585 /*
586 * Flush all pending writes before doing anything
587 * with locks..
588 */
29884df0
TM
589 status = nfs_sync_mapping(filp->f_mapping);
590 if (status != 0)
1da177e4
LT
591 goto out;
592
593 lock_kernel();
594 /* Use local locking if mounted with "-onolock" */
c4d7c402 595 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
1da177e4 596 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
c4d7c402 597 else
1da177e4
LT
598 status = do_vfs_lock(filp, fl);
599 unlock_kernel();
600 if (status < 0)
601 goto out;
602 /*
603 * Make sure we clear the cache whenever we try to get the lock.
604 * This makes locking act as a cache coherency point.
605 */
29884df0 606 nfs_sync_mapping(filp->f_mapping);
b5418383
TM
607 if (!nfs_have_delegation(inode, FMODE_READ))
608 nfs_zap_caches(inode);
1da177e4 609out:
1da177e4
LT
610 return status;
611}
612
613/*
614 * Lock a (portion of) a file
615 */
616static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
617{
618 struct inode * inode = filp->f_mapping->host;
2116271a 619 int ret = -ENOLCK;
1da177e4
LT
620
621 dprintk("NFS: nfs_lock(f=%s/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n",
622 inode->i_sb->s_id, inode->i_ino,
623 fl->fl_type, fl->fl_flags,
624 (long long)fl->fl_start, (long long)fl->fl_end);
91d5b470 625 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
1da177e4
LT
626
627 /* No mandatory locks over NFS */
dfad9441 628 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
2116271a
TM
629 goto out_err;
630
631 if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
632 ret = NFS_PROTO(inode)->lock_check_bounds(fl);
633 if (ret < 0)
634 goto out_err;
635 }
1da177e4
LT
636
637 if (IS_GETLK(cmd))
2116271a
TM
638 ret = do_getlk(filp, cmd, fl);
639 else if (fl->fl_type == F_UNLCK)
640 ret = do_unlk(filp, cmd, fl);
641 else
642 ret = do_setlk(filp, cmd, fl);
643out_err:
644 return ret;
1da177e4
LT
645}
646
647/*
648 * Lock a (portion of) a file
649 */
650static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
651{
1da177e4 652 dprintk("NFS: nfs_flock(f=%s/%ld, t=%x, fl=%x)\n",
01cce933
JJS
653 filp->f_path.dentry->d_inode->i_sb->s_id,
654 filp->f_path.dentry->d_inode->i_ino,
1da177e4
LT
655 fl->fl_type, fl->fl_flags);
656
1da177e4
LT
657 /*
658 * No BSD flocks over NFS allowed.
659 * Note: we could try to fake a POSIX lock request here by
660 * using ((u32) filp | 0x80000000) or some such as the pid.
661 * Not sure whether that would be unique, though, or whether
662 * that would break in other places.
663 */
664 if (!(fl->fl_flags & FL_FLOCK))
665 return -ENOLCK;
666
667 /* We're simulating flock() locks using posix locks on the server */
668 fl->fl_owner = (fl_owner_t)filp;
669 fl->fl_start = 0;
670 fl->fl_end = OFFSET_MAX;
671
672 if (fl->fl_type == F_UNLCK)
673 return do_unlk(filp, cmd, fl);
674 return do_setlk(filp, cmd, fl);
675}
370f6599
BF
676
677static int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
678{
679 /*
680 * There is no protocol support for leases, so we have no way
681 * to implement them correctly in the face of opens by other
682 * clients.
683 */
684 return -EINVAL;
685}