mm: page_mkwrite change prototype to match fault
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / nfs / file.c
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>
30 #include <linux/aio.h>
31
32 #include <asm/uaccess.h>
33 #include <asm/system.h>
34
35 #include "delegation.h"
36 #include "internal.h"
37 #include "iostat.h"
38
39 #define NFSDBG_FACILITY NFSDBG_FILE
40
41 static int nfs_file_open(struct inode *, struct file *);
42 static int nfs_file_release(struct inode *, struct file *);
43 static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin);
44 static int nfs_file_mmap(struct file *, struct vm_area_struct *);
45 static 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);
48 static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov,
49 unsigned long nr_segs, loff_t pos);
50 static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov,
51 unsigned long nr_segs, loff_t pos);
52 static int nfs_file_flush(struct file *, fl_owner_t id);
53 static int nfs_file_fsync(struct file *, struct dentry *dentry, int datasync);
54 static int nfs_check_flags(int flags);
55 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
56 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
57 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl);
58
59 static struct vm_operations_struct nfs_file_vm_ops;
60
61 const struct file_operations nfs_file_operations = {
62 .llseek = nfs_file_llseek,
63 .read = do_sync_read,
64 .write = do_sync_write,
65 .aio_read = nfs_file_read,
66 .aio_write = nfs_file_write,
67 #ifdef CONFIG_MMU
68 .mmap = nfs_file_mmap,
69 #else
70 .mmap = generic_file_mmap,
71 #endif
72 .open = nfs_file_open,
73 .flush = nfs_file_flush,
74 .release = nfs_file_release,
75 .fsync = nfs_file_fsync,
76 .lock = nfs_lock,
77 .flock = nfs_flock,
78 .splice_read = nfs_file_splice_read,
79 .check_flags = nfs_check_flags,
80 .setlease = nfs_setlease,
81 };
82
83 const struct inode_operations nfs_file_inode_operations = {
84 .permission = nfs_permission,
85 .getattr = nfs_getattr,
86 .setattr = nfs_setattr,
87 };
88
89 #ifdef CONFIG_NFS_V3
90 const struct inode_operations nfs3_file_inode_operations = {
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
101 /* Hack for future NFS swap support */
102 #ifndef IS_SWAPFILE
103 # define IS_SWAPFILE(inode) (0)
104 #endif
105
106 static 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 */
117 static int
118 nfs_file_open(struct inode *inode, struct file *filp)
119 {
120 int res;
121
122 dprintk("NFS: open file(%s/%s)\n",
123 filp->f_path.dentry->d_parent->d_name.name,
124 filp->f_path.dentry->d_name.name);
125
126 res = nfs_check_flags(filp->f_flags);
127 if (res)
128 return res;
129
130 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
131 res = nfs_open(inode, filp);
132 return res;
133 }
134
135 static int
136 nfs_file_release(struct inode *inode, struct file *filp)
137 {
138 struct dentry *dentry = filp->f_path.dentry;
139
140 dprintk("NFS: release(%s/%s)\n",
141 dentry->d_parent->d_name.name,
142 dentry->d_name.name);
143
144 /* Ensure that dirty pages are flushed out with the right creds */
145 if (filp->f_mode & FMODE_WRITE)
146 nfs_wb_all(dentry->d_inode);
147 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
148 return nfs_release(inode, filp);
149 }
150
151 /**
152 * nfs_revalidate_size - Revalidate the file size
153 * @inode - pointer to inode struct
154 * @file - pointer to struct file
155 *
156 * Revalidates the file length. This is basically a wrapper around
157 * nfs_revalidate_inode() that takes into account the fact that we may
158 * have cached writes (in which case we don't care about the server's
159 * idea of what the file length is), or O_DIRECT (in which case we
160 * shouldn't trust the cache).
161 */
162 static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
163 {
164 struct nfs_server *server = NFS_SERVER(inode);
165 struct nfs_inode *nfsi = NFS_I(inode);
166
167 if (server->flags & NFS_MOUNT_NOAC)
168 goto force_reval;
169 if (filp->f_flags & O_DIRECT)
170 goto force_reval;
171 if (nfsi->npages != 0)
172 return 0;
173 if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode))
174 return 0;
175 force_reval:
176 return __nfs_revalidate_inode(server, inode);
177 }
178
179 static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
180 {
181 loff_t loff;
182
183 dprintk("NFS: llseek file(%s/%s, %lld, %d)\n",
184 filp->f_path.dentry->d_parent->d_name.name,
185 filp->f_path.dentry->d_name.name,
186 offset, origin);
187
188 /* origin == SEEK_END => we must revalidate the cached file length */
189 if (origin == SEEK_END) {
190 struct inode *inode = filp->f_mapping->host;
191
192 int retval = nfs_revalidate_file_size(inode, filp);
193 if (retval < 0)
194 return (loff_t)retval;
195
196 spin_lock(&inode->i_lock);
197 loff = generic_file_llseek_unlocked(filp, offset, origin);
198 spin_unlock(&inode->i_lock);
199 } else
200 loff = generic_file_llseek_unlocked(filp, offset, origin);
201 return loff;
202 }
203
204 /*
205 * Helper for nfs_file_flush() and nfs_file_fsync()
206 *
207 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
208 * disk, but it retrieves and clears ctx->error after synching, despite
209 * the two being set at the same time in nfs_context_set_write_error().
210 * This is because the former is used to notify the _next_ call to
211 * nfs_file_write() that a write error occured, and hence cause it to
212 * fall back to doing a synchronous write.
213 */
214 static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode)
215 {
216 int have_error, status;
217 int ret = 0;
218
219 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
220 status = nfs_wb_all(inode);
221 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
222 if (have_error)
223 ret = xchg(&ctx->error, 0);
224 if (!ret)
225 ret = status;
226 return ret;
227 }
228
229 /*
230 * Flush all dirty pages, and check for write errors.
231 */
232 static int
233 nfs_file_flush(struct file *file, fl_owner_t id)
234 {
235 struct nfs_open_context *ctx = nfs_file_open_context(file);
236 struct dentry *dentry = file->f_path.dentry;
237 struct inode *inode = dentry->d_inode;
238 int status;
239
240 dprintk("NFS: flush(%s/%s)\n",
241 dentry->d_parent->d_name.name,
242 dentry->d_name.name);
243
244 if ((file->f_mode & FMODE_WRITE) == 0)
245 return 0;
246 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
247
248 /* Ensure that data+attribute caches are up to date after close() */
249 status = nfs_do_fsync(ctx, inode);
250 if (!status)
251 nfs_revalidate_inode(NFS_SERVER(inode), inode);
252 return status;
253 }
254
255 static ssize_t
256 nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
257 unsigned long nr_segs, loff_t pos)
258 {
259 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
260 struct inode * inode = dentry->d_inode;
261 ssize_t result;
262 size_t count = iov_length(iov, nr_segs);
263
264 if (iocb->ki_filp->f_flags & O_DIRECT)
265 return nfs_file_direct_read(iocb, iov, nr_segs, pos);
266
267 dprintk("NFS: read(%s/%s, %lu@%lu)\n",
268 dentry->d_parent->d_name.name, dentry->d_name.name,
269 (unsigned long) count, (unsigned long) pos);
270
271 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
272 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count);
273 if (!result)
274 result = generic_file_aio_read(iocb, iov, nr_segs, pos);
275 return result;
276 }
277
278 static ssize_t
279 nfs_file_splice_read(struct file *filp, loff_t *ppos,
280 struct pipe_inode_info *pipe, size_t count,
281 unsigned int flags)
282 {
283 struct dentry *dentry = filp->f_path.dentry;
284 struct inode *inode = dentry->d_inode;
285 ssize_t res;
286
287 dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n",
288 dentry->d_parent->d_name.name, dentry->d_name.name,
289 (unsigned long) count, (unsigned long long) *ppos);
290
291 res = nfs_revalidate_mapping(inode, filp->f_mapping);
292 if (!res)
293 res = generic_file_splice_read(filp, ppos, pipe, count, flags);
294 return res;
295 }
296
297 static int
298 nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
299 {
300 struct dentry *dentry = file->f_path.dentry;
301 struct inode *inode = dentry->d_inode;
302 int status;
303
304 dprintk("NFS: mmap(%s/%s)\n",
305 dentry->d_parent->d_name.name, dentry->d_name.name);
306
307 status = nfs_revalidate_mapping(inode, file->f_mapping);
308 if (!status) {
309 vma->vm_ops = &nfs_file_vm_ops;
310 vma->vm_flags |= VM_CAN_NONLINEAR;
311 file_accessed(file);
312 }
313 return status;
314 }
315
316 /*
317 * Flush any dirty pages for this process, and check for write errors.
318 * The return status from this call provides a reliable indication of
319 * whether any write errors occurred for this process.
320 */
321 static int
322 nfs_file_fsync(struct file *file, struct dentry *dentry, int datasync)
323 {
324 struct nfs_open_context *ctx = nfs_file_open_context(file);
325 struct inode *inode = dentry->d_inode;
326
327 dprintk("NFS: fsync file(%s/%s) datasync %d\n",
328 dentry->d_parent->d_name.name, dentry->d_name.name,
329 datasync);
330
331 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
332 return nfs_do_fsync(ctx, inode);
333 }
334
335 /*
336 * This does the "real" work of the write. We must allocate and lock the
337 * page to be sent back to the generic routine, which then copies the
338 * data from user space.
339 *
340 * If the writer ends up delaying the write, the writer needs to
341 * increment the page use counts until he is done with the page.
342 */
343 static int nfs_write_begin(struct file *file, struct address_space *mapping,
344 loff_t pos, unsigned len, unsigned flags,
345 struct page **pagep, void **fsdata)
346 {
347 int ret;
348 pgoff_t index;
349 struct page *page;
350 index = pos >> PAGE_CACHE_SHIFT;
351
352 dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n",
353 file->f_path.dentry->d_parent->d_name.name,
354 file->f_path.dentry->d_name.name,
355 mapping->host->i_ino, len, (long long) pos);
356
357 page = grab_cache_page_write_begin(mapping, index, flags);
358 if (!page)
359 return -ENOMEM;
360 *pagep = page;
361
362 ret = nfs_flush_incompatible(file, page);
363 if (ret) {
364 unlock_page(page);
365 page_cache_release(page);
366 }
367 return ret;
368 }
369
370 static int nfs_write_end(struct file *file, struct address_space *mapping,
371 loff_t pos, unsigned len, unsigned copied,
372 struct page *page, void *fsdata)
373 {
374 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
375 int status;
376
377 dfprintk(PAGECACHE, "NFS: write_end(%s/%s(%ld), %u@%lld)\n",
378 file->f_path.dentry->d_parent->d_name.name,
379 file->f_path.dentry->d_name.name,
380 mapping->host->i_ino, len, (long long) pos);
381
382 /*
383 * Zero any uninitialised parts of the page, and then mark the page
384 * as up to date if it turns out that we're extending the file.
385 */
386 if (!PageUptodate(page)) {
387 unsigned pglen = nfs_page_length(page);
388 unsigned end = offset + len;
389
390 if (pglen == 0) {
391 zero_user_segments(page, 0, offset,
392 end, PAGE_CACHE_SIZE);
393 SetPageUptodate(page);
394 } else if (end >= pglen) {
395 zero_user_segment(page, end, PAGE_CACHE_SIZE);
396 if (offset == 0)
397 SetPageUptodate(page);
398 } else
399 zero_user_segment(page, pglen, PAGE_CACHE_SIZE);
400 }
401
402 status = nfs_updatepage(file, page, offset, copied);
403
404 unlock_page(page);
405 page_cache_release(page);
406
407 if (status < 0)
408 return status;
409 return copied;
410 }
411
412 static void nfs_invalidate_page(struct page *page, unsigned long offset)
413 {
414 dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset);
415
416 if (offset != 0)
417 return;
418 /* Cancel any unstarted writes on this page */
419 nfs_wb_page_cancel(page->mapping->host, page);
420 }
421
422 static int nfs_release_page(struct page *page, gfp_t gfp)
423 {
424 dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
425
426 /* If PagePrivate() is set, then the page is not freeable */
427 return 0;
428 }
429
430 static int nfs_launder_page(struct page *page)
431 {
432 struct inode *inode = page->mapping->host;
433
434 dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
435 inode->i_ino, (long long)page_offset(page));
436
437 return nfs_wb_page(inode, page);
438 }
439
440 const struct address_space_operations nfs_file_aops = {
441 .readpage = nfs_readpage,
442 .readpages = nfs_readpages,
443 .set_page_dirty = __set_page_dirty_nobuffers,
444 .writepage = nfs_writepage,
445 .writepages = nfs_writepages,
446 .write_begin = nfs_write_begin,
447 .write_end = nfs_write_end,
448 .invalidatepage = nfs_invalidate_page,
449 .releasepage = nfs_release_page,
450 .direct_IO = nfs_direct_IO,
451 .launder_page = nfs_launder_page,
452 };
453
454 static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
455 {
456 struct page *page = vmf->page;
457 struct file *filp = vma->vm_file;
458 struct dentry *dentry = filp->f_path.dentry;
459 unsigned pagelen;
460 int ret = -EINVAL;
461 struct address_space *mapping;
462
463 dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n",
464 dentry->d_parent->d_name.name, dentry->d_name.name,
465 filp->f_mapping->host->i_ino,
466 (long long)page_offset(page));
467
468 lock_page(page);
469 mapping = page->mapping;
470 if (mapping != dentry->d_inode->i_mapping)
471 goto out_unlock;
472
473 ret = 0;
474 pagelen = nfs_page_length(page);
475 if (pagelen == 0)
476 goto out_unlock;
477
478 ret = nfs_flush_incompatible(filp, page);
479 if (ret != 0)
480 goto out_unlock;
481
482 ret = nfs_updatepage(filp, page, 0, pagelen);
483 if (ret == 0)
484 ret = pagelen;
485 out_unlock:
486 unlock_page(page);
487 if (ret)
488 ret = VM_FAULT_SIGBUS;
489 return ret;
490 }
491
492 static struct vm_operations_struct nfs_file_vm_ops = {
493 .fault = filemap_fault,
494 .page_mkwrite = nfs_vm_page_mkwrite,
495 };
496
497 static int nfs_need_sync_write(struct file *filp, struct inode *inode)
498 {
499 struct nfs_open_context *ctx;
500
501 if (IS_SYNC(inode) || (filp->f_flags & O_SYNC))
502 return 1;
503 ctx = nfs_file_open_context(filp);
504 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags))
505 return 1;
506 return 0;
507 }
508
509 static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov,
510 unsigned long nr_segs, loff_t pos)
511 {
512 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
513 struct inode * inode = dentry->d_inode;
514 ssize_t result;
515 size_t count = iov_length(iov, nr_segs);
516
517 if (iocb->ki_filp->f_flags & O_DIRECT)
518 return nfs_file_direct_write(iocb, iov, nr_segs, pos);
519
520 dprintk("NFS: write(%s/%s, %lu@%Ld)\n",
521 dentry->d_parent->d_name.name, dentry->d_name.name,
522 (unsigned long) count, (long long) pos);
523
524 result = -EBUSY;
525 if (IS_SWAPFILE(inode))
526 goto out_swapfile;
527 /*
528 * O_APPEND implies that we must revalidate the file length.
529 */
530 if (iocb->ki_filp->f_flags & O_APPEND) {
531 result = nfs_revalidate_file_size(inode, iocb->ki_filp);
532 if (result)
533 goto out;
534 }
535
536 result = count;
537 if (!count)
538 goto out;
539
540 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count);
541 result = generic_file_aio_write(iocb, iov, nr_segs, pos);
542 /* Return error values for O_SYNC and IS_SYNC() */
543 if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) {
544 int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode);
545 if (err < 0)
546 result = err;
547 }
548 out:
549 return result;
550
551 out_swapfile:
552 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
553 goto out;
554 }
555
556 static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
557 {
558 struct inode *inode = filp->f_mapping->host;
559 int status = 0;
560
561 lock_kernel();
562 /* Try local locking first */
563 posix_test_lock(filp, fl);
564 if (fl->fl_type != F_UNLCK) {
565 /* found a conflict */
566 goto out;
567 }
568
569 if (nfs_have_delegation(inode, FMODE_READ))
570 goto out_noconflict;
571
572 if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)
573 goto out_noconflict;
574
575 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
576 out:
577 unlock_kernel();
578 return status;
579 out_noconflict:
580 fl->fl_type = F_UNLCK;
581 goto out;
582 }
583
584 static int do_vfs_lock(struct file *file, struct file_lock *fl)
585 {
586 int res = 0;
587 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
588 case FL_POSIX:
589 res = posix_lock_file_wait(file, fl);
590 break;
591 case FL_FLOCK:
592 res = flock_lock_file_wait(file, fl);
593 break;
594 default:
595 BUG();
596 }
597 if (res < 0)
598 dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager"
599 " - error %d!\n",
600 __func__, res);
601 return res;
602 }
603
604 static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
605 {
606 struct inode *inode = filp->f_mapping->host;
607 int status;
608
609 /*
610 * Flush all pending writes before doing anything
611 * with locks..
612 */
613 nfs_sync_mapping(filp->f_mapping);
614
615 /* NOTE: special case
616 * If we're signalled while cleaning up locks on process exit, we
617 * still need to complete the unlock.
618 */
619 lock_kernel();
620 /* Use local locking if mounted with "-onolock" */
621 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
622 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
623 else
624 status = do_vfs_lock(filp, fl);
625 unlock_kernel();
626 return status;
627 }
628
629 static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
630 {
631 struct inode *inode = filp->f_mapping->host;
632 int status;
633
634 /*
635 * Flush all pending writes before doing anything
636 * with locks..
637 */
638 status = nfs_sync_mapping(filp->f_mapping);
639 if (status != 0)
640 goto out;
641
642 lock_kernel();
643 /* Use local locking if mounted with "-onolock" */
644 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
645 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
646 else
647 status = do_vfs_lock(filp, fl);
648 unlock_kernel();
649 if (status < 0)
650 goto out;
651 /*
652 * Make sure we clear the cache whenever we try to get the lock.
653 * This makes locking act as a cache coherency point.
654 */
655 nfs_sync_mapping(filp->f_mapping);
656 if (!nfs_have_delegation(inode, FMODE_READ))
657 nfs_zap_caches(inode);
658 out:
659 return status;
660 }
661
662 /*
663 * Lock a (portion of) a file
664 */
665 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
666 {
667 struct inode *inode = filp->f_mapping->host;
668 int ret = -ENOLCK;
669
670 dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n",
671 filp->f_path.dentry->d_parent->d_name.name,
672 filp->f_path.dentry->d_name.name,
673 fl->fl_type, fl->fl_flags,
674 (long long)fl->fl_start, (long long)fl->fl_end);
675
676 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
677
678 /* No mandatory locks over NFS */
679 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
680 goto out_err;
681
682 if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
683 ret = NFS_PROTO(inode)->lock_check_bounds(fl);
684 if (ret < 0)
685 goto out_err;
686 }
687
688 if (IS_GETLK(cmd))
689 ret = do_getlk(filp, cmd, fl);
690 else if (fl->fl_type == F_UNLCK)
691 ret = do_unlk(filp, cmd, fl);
692 else
693 ret = do_setlk(filp, cmd, fl);
694 out_err:
695 return ret;
696 }
697
698 /*
699 * Lock a (portion of) a file
700 */
701 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
702 {
703 dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n",
704 filp->f_path.dentry->d_parent->d_name.name,
705 filp->f_path.dentry->d_name.name,
706 fl->fl_type, fl->fl_flags);
707
708 if (!(fl->fl_flags & FL_FLOCK))
709 return -ENOLCK;
710
711 /* We're simulating flock() locks using posix locks on the server */
712 fl->fl_owner = (fl_owner_t)filp;
713 fl->fl_start = 0;
714 fl->fl_end = OFFSET_MAX;
715
716 if (fl->fl_type == F_UNLCK)
717 return do_unlk(filp, cmd, fl);
718 return do_setlk(filp, cmd, fl);
719 }
720
721 /*
722 * There is no protocol support for leases, so we have no way to implement
723 * them correctly in the face of opens by other clients.
724 */
725 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
726 {
727 dprintk("NFS: setlease(%s/%s, arg=%ld)\n",
728 file->f_path.dentry->d_parent->d_name.name,
729 file->f_path.dentry->d_name.name, arg);
730
731 return -EINVAL;
732 }