f5bc54dccecbf6746dc2200b04baea5d27b8cfac
[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 .mmap = nfs_file_mmap,
68 .open = nfs_file_open,
69 .flush = nfs_file_flush,
70 .release = nfs_file_release,
71 .fsync = nfs_file_fsync,
72 .lock = nfs_lock,
73 .flock = nfs_flock,
74 .splice_read = nfs_file_splice_read,
75 .check_flags = nfs_check_flags,
76 .setlease = nfs_setlease,
77 };
78
79 const struct inode_operations nfs_file_inode_operations = {
80 .permission = nfs_permission,
81 .getattr = nfs_getattr,
82 .setattr = nfs_setattr,
83 };
84
85 #ifdef CONFIG_NFS_V3
86 const struct inode_operations nfs3_file_inode_operations = {
87 .permission = nfs_permission,
88 .getattr = nfs_getattr,
89 .setattr = nfs_setattr,
90 .listxattr = nfs3_listxattr,
91 .getxattr = nfs3_getxattr,
92 .setxattr = nfs3_setxattr,
93 .removexattr = nfs3_removexattr,
94 };
95 #endif /* CONFIG_NFS_v3 */
96
97 /* Hack for future NFS swap support */
98 #ifndef IS_SWAPFILE
99 # define IS_SWAPFILE(inode) (0)
100 #endif
101
102 static int nfs_check_flags(int flags)
103 {
104 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
105 return -EINVAL;
106
107 return 0;
108 }
109
110 /*
111 * Open file
112 */
113 static int
114 nfs_file_open(struct inode *inode, struct file *filp)
115 {
116 int res;
117
118 dprintk("NFS: open file(%s/%s)\n",
119 filp->f_path.dentry->d_parent->d_name.name,
120 filp->f_path.dentry->d_name.name);
121
122 res = nfs_check_flags(filp->f_flags);
123 if (res)
124 return res;
125
126 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
127 res = nfs_open(inode, filp);
128 return res;
129 }
130
131 static int
132 nfs_file_release(struct inode *inode, struct file *filp)
133 {
134 struct dentry *dentry = filp->f_path.dentry;
135
136 dprintk("NFS: release(%s/%s)\n",
137 dentry->d_parent->d_name.name,
138 dentry->d_name.name);
139
140 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
141 return nfs_release(inode, filp);
142 }
143
144 /**
145 * nfs_revalidate_size - Revalidate the file size
146 * @inode - pointer to inode struct
147 * @file - pointer to struct file
148 *
149 * Revalidates the file length. This is basically a wrapper around
150 * nfs_revalidate_inode() that takes into account the fact that we may
151 * have cached writes (in which case we don't care about the server's
152 * idea of what the file length is), or O_DIRECT (in which case we
153 * shouldn't trust the cache).
154 */
155 static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
156 {
157 struct nfs_server *server = NFS_SERVER(inode);
158 struct nfs_inode *nfsi = NFS_I(inode);
159
160 if (server->flags & NFS_MOUNT_NOAC)
161 goto force_reval;
162 if (filp->f_flags & O_DIRECT)
163 goto force_reval;
164 if (nfsi->npages != 0)
165 return 0;
166 if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode))
167 return 0;
168 force_reval:
169 return __nfs_revalidate_inode(server, inode);
170 }
171
172 static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
173 {
174 loff_t loff;
175
176 dprintk("NFS: llseek file(%s/%s, %lld, %d)\n",
177 filp->f_path.dentry->d_parent->d_name.name,
178 filp->f_path.dentry->d_name.name,
179 offset, origin);
180
181 /* origin == SEEK_END => we must revalidate the cached file length */
182 if (origin == SEEK_END) {
183 struct inode *inode = filp->f_mapping->host;
184
185 int retval = nfs_revalidate_file_size(inode, filp);
186 if (retval < 0)
187 return (loff_t)retval;
188
189 spin_lock(&inode->i_lock);
190 loff = generic_file_llseek_unlocked(filp, offset, origin);
191 spin_unlock(&inode->i_lock);
192 } else
193 loff = generic_file_llseek_unlocked(filp, offset, origin);
194 return loff;
195 }
196
197 /*
198 * Helper for nfs_file_flush() and nfs_file_fsync()
199 *
200 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
201 * disk, but it retrieves and clears ctx->error after synching, despite
202 * the two being set at the same time in nfs_context_set_write_error().
203 * This is because the former is used to notify the _next_ call to
204 * nfs_file_write() that a write error occured, and hence cause it to
205 * fall back to doing a synchronous write.
206 */
207 static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode)
208 {
209 int have_error, status;
210 int ret = 0;
211
212 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
213 status = nfs_wb_all(inode);
214 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
215 if (have_error)
216 ret = xchg(&ctx->error, 0);
217 if (!ret)
218 ret = status;
219 return ret;
220 }
221
222 /*
223 * Flush all dirty pages, and check for write errors.
224 */
225 static int
226 nfs_file_flush(struct file *file, fl_owner_t id)
227 {
228 struct nfs_open_context *ctx = nfs_file_open_context(file);
229 struct dentry *dentry = file->f_path.dentry;
230 struct inode *inode = dentry->d_inode;
231
232 dprintk("NFS: flush(%s/%s)\n",
233 dentry->d_parent->d_name.name,
234 dentry->d_name.name);
235
236 if ((file->f_mode & FMODE_WRITE) == 0)
237 return 0;
238 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
239
240 /* Flush writes to the server and return any errors */
241 return nfs_do_fsync(ctx, inode);
242 }
243
244 static ssize_t
245 nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
246 unsigned long nr_segs, loff_t pos)
247 {
248 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
249 struct inode * inode = dentry->d_inode;
250 ssize_t result;
251 size_t count = iov_length(iov, nr_segs);
252
253 if (iocb->ki_filp->f_flags & O_DIRECT)
254 return nfs_file_direct_read(iocb, iov, nr_segs, pos);
255
256 dprintk("NFS: read(%s/%s, %lu@%lu)\n",
257 dentry->d_parent->d_name.name, dentry->d_name.name,
258 (unsigned long) count, (unsigned long) pos);
259
260 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
261 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count);
262 if (!result)
263 result = generic_file_aio_read(iocb, iov, nr_segs, pos);
264 return result;
265 }
266
267 static ssize_t
268 nfs_file_splice_read(struct file *filp, loff_t *ppos,
269 struct pipe_inode_info *pipe, size_t count,
270 unsigned int flags)
271 {
272 struct dentry *dentry = filp->f_path.dentry;
273 struct inode *inode = dentry->d_inode;
274 ssize_t res;
275
276 dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n",
277 dentry->d_parent->d_name.name, dentry->d_name.name,
278 (unsigned long) count, (unsigned long long) *ppos);
279
280 res = nfs_revalidate_mapping(inode, filp->f_mapping);
281 if (!res)
282 res = generic_file_splice_read(filp, ppos, pipe, count, flags);
283 return res;
284 }
285
286 static int
287 nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
288 {
289 struct dentry *dentry = file->f_path.dentry;
290 struct inode *inode = dentry->d_inode;
291 int status;
292
293 dprintk("NFS: mmap(%s/%s)\n",
294 dentry->d_parent->d_name.name, dentry->d_name.name);
295
296 /* Note: generic_file_mmap() returns ENOSYS on nommu systems
297 * so we call that before revalidating the mapping
298 */
299 status = generic_file_mmap(file, vma);
300 if (!status) {
301 vma->vm_ops = &nfs_file_vm_ops;
302 status = nfs_revalidate_mapping(inode, file->f_mapping);
303 }
304 return status;
305 }
306
307 /*
308 * Flush any dirty pages for this process, and check for write errors.
309 * The return status from this call provides a reliable indication of
310 * whether any write errors occurred for this process.
311 */
312 static int
313 nfs_file_fsync(struct file *file, struct dentry *dentry, int datasync)
314 {
315 struct nfs_open_context *ctx = nfs_file_open_context(file);
316 struct inode *inode = dentry->d_inode;
317
318 dprintk("NFS: fsync file(%s/%s) datasync %d\n",
319 dentry->d_parent->d_name.name, dentry->d_name.name,
320 datasync);
321
322 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
323 return nfs_do_fsync(ctx, inode);
324 }
325
326 /*
327 * This does the "real" work of the write. We must allocate and lock the
328 * page to be sent back to the generic routine, which then copies the
329 * data from user space.
330 *
331 * If the writer ends up delaying the write, the writer needs to
332 * increment the page use counts until he is done with the page.
333 */
334 static int nfs_write_begin(struct file *file, struct address_space *mapping,
335 loff_t pos, unsigned len, unsigned flags,
336 struct page **pagep, void **fsdata)
337 {
338 int ret;
339 pgoff_t index;
340 struct page *page;
341 index = pos >> PAGE_CACHE_SHIFT;
342
343 dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n",
344 file->f_path.dentry->d_parent->d_name.name,
345 file->f_path.dentry->d_name.name,
346 mapping->host->i_ino, len, (long long) pos);
347
348 /*
349 * Prevent starvation issues if someone is doing a consistency
350 * sync-to-disk
351 */
352 ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING,
353 nfs_wait_bit_killable, TASK_KILLABLE);
354 if (ret)
355 return ret;
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 /*
413 * Partially or wholly invalidate a page
414 * - Release the private state associated with a page if undergoing complete
415 * page invalidation
416 * - Called if either PG_private or PG_private_2 is set on the page
417 * - Caller holds page lock
418 */
419 static void nfs_invalidate_page(struct page *page, unsigned long offset)
420 {
421 dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset);
422
423 if (offset != 0)
424 return;
425 /* Cancel any unstarted writes on this page */
426 nfs_wb_page_cancel(page->mapping->host, page);
427 }
428
429 /*
430 * Attempt to release the private state associated with a page
431 * - Called if either PG_private or PG_private_2 is set on the page
432 * - Caller holds page lock
433 * - Return true (may release page) or false (may not)
434 */
435 static int nfs_release_page(struct page *page, gfp_t gfp)
436 {
437 dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
438
439 /* If PagePrivate() is set, then the page is not freeable */
440 return 0;
441 }
442
443 /*
444 * Attempt to clear the private state associated with a page when an error
445 * occurs that requires the cached contents of an inode to be written back or
446 * destroyed
447 * - Called if either PG_private or PG_private_2 is set on the page
448 * - Caller holds page lock
449 * - Return 0 if successful, -error otherwise
450 */
451 static int nfs_launder_page(struct page *page)
452 {
453 struct inode *inode = page->mapping->host;
454
455 dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
456 inode->i_ino, (long long)page_offset(page));
457
458 return nfs_wb_page(inode, page);
459 }
460
461 const struct address_space_operations nfs_file_aops = {
462 .readpage = nfs_readpage,
463 .readpages = nfs_readpages,
464 .set_page_dirty = __set_page_dirty_nobuffers,
465 .writepage = nfs_writepage,
466 .writepages = nfs_writepages,
467 .write_begin = nfs_write_begin,
468 .write_end = nfs_write_end,
469 .invalidatepage = nfs_invalidate_page,
470 .releasepage = nfs_release_page,
471 .direct_IO = nfs_direct_IO,
472 .launder_page = nfs_launder_page,
473 };
474
475 /*
476 * Notification that a PTE pointing to an NFS page is about to be made
477 * writable, implying that someone is about to modify the page through a
478 * shared-writable mapping
479 */
480 static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
481 {
482 struct page *page = vmf->page;
483 struct file *filp = vma->vm_file;
484 struct dentry *dentry = filp->f_path.dentry;
485 unsigned pagelen;
486 int ret = -EINVAL;
487 struct address_space *mapping;
488
489 dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n",
490 dentry->d_parent->d_name.name, dentry->d_name.name,
491 filp->f_mapping->host->i_ino,
492 (long long)page_offset(page));
493
494 lock_page(page);
495 mapping = page->mapping;
496 if (mapping != dentry->d_inode->i_mapping)
497 goto out_unlock;
498
499 ret = 0;
500 pagelen = nfs_page_length(page);
501 if (pagelen == 0)
502 goto out_unlock;
503
504 ret = nfs_flush_incompatible(filp, page);
505 if (ret != 0)
506 goto out_unlock;
507
508 ret = nfs_updatepage(filp, page, 0, pagelen);
509 if (ret == 0)
510 ret = pagelen;
511 out_unlock:
512 unlock_page(page);
513 if (ret)
514 ret = VM_FAULT_SIGBUS;
515 return ret;
516 }
517
518 static struct vm_operations_struct nfs_file_vm_ops = {
519 .fault = filemap_fault,
520 .page_mkwrite = nfs_vm_page_mkwrite,
521 };
522
523 static int nfs_need_sync_write(struct file *filp, struct inode *inode)
524 {
525 struct nfs_open_context *ctx;
526
527 if (IS_SYNC(inode) || (filp->f_flags & O_SYNC))
528 return 1;
529 ctx = nfs_file_open_context(filp);
530 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags))
531 return 1;
532 return 0;
533 }
534
535 static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov,
536 unsigned long nr_segs, loff_t pos)
537 {
538 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
539 struct inode * inode = dentry->d_inode;
540 ssize_t result;
541 size_t count = iov_length(iov, nr_segs);
542
543 if (iocb->ki_filp->f_flags & O_DIRECT)
544 return nfs_file_direct_write(iocb, iov, nr_segs, pos);
545
546 dprintk("NFS: write(%s/%s, %lu@%Ld)\n",
547 dentry->d_parent->d_name.name, dentry->d_name.name,
548 (unsigned long) count, (long long) pos);
549
550 result = -EBUSY;
551 if (IS_SWAPFILE(inode))
552 goto out_swapfile;
553 /*
554 * O_APPEND implies that we must revalidate the file length.
555 */
556 if (iocb->ki_filp->f_flags & O_APPEND) {
557 result = nfs_revalidate_file_size(inode, iocb->ki_filp);
558 if (result)
559 goto out;
560 }
561
562 result = count;
563 if (!count)
564 goto out;
565
566 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count);
567 result = generic_file_aio_write(iocb, iov, nr_segs, pos);
568 /* Return error values for O_SYNC and IS_SYNC() */
569 if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) {
570 int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode);
571 if (err < 0)
572 result = err;
573 }
574 out:
575 return result;
576
577 out_swapfile:
578 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
579 goto out;
580 }
581
582 static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
583 {
584 struct inode *inode = filp->f_mapping->host;
585 int status = 0;
586
587 lock_kernel();
588 /* Try local locking first */
589 posix_test_lock(filp, fl);
590 if (fl->fl_type != F_UNLCK) {
591 /* found a conflict */
592 goto out;
593 }
594
595 if (nfs_have_delegation(inode, FMODE_READ))
596 goto out_noconflict;
597
598 if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)
599 goto out_noconflict;
600
601 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
602 out:
603 unlock_kernel();
604 return status;
605 out_noconflict:
606 fl->fl_type = F_UNLCK;
607 goto out;
608 }
609
610 static int do_vfs_lock(struct file *file, struct file_lock *fl)
611 {
612 int res = 0;
613 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
614 case FL_POSIX:
615 res = posix_lock_file_wait(file, fl);
616 break;
617 case FL_FLOCK:
618 res = flock_lock_file_wait(file, fl);
619 break;
620 default:
621 BUG();
622 }
623 if (res < 0)
624 dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager"
625 " - error %d!\n",
626 __func__, res);
627 return res;
628 }
629
630 static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
631 {
632 struct inode *inode = filp->f_mapping->host;
633 int status;
634
635 /*
636 * Flush all pending writes before doing anything
637 * with locks..
638 */
639 nfs_sync_mapping(filp->f_mapping);
640
641 /* NOTE: special case
642 * If we're signalled while cleaning up locks on process exit, we
643 * still need to complete the unlock.
644 */
645 lock_kernel();
646 /* Use local locking if mounted with "-onolock" */
647 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
648 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
649 else
650 status = do_vfs_lock(filp, fl);
651 unlock_kernel();
652 return status;
653 }
654
655 static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
656 {
657 struct inode *inode = filp->f_mapping->host;
658 int status;
659
660 /*
661 * Flush all pending writes before doing anything
662 * with locks..
663 */
664 status = nfs_sync_mapping(filp->f_mapping);
665 if (status != 0)
666 goto out;
667
668 lock_kernel();
669 /* Use local locking if mounted with "-onolock" */
670 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
671 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
672 else
673 status = do_vfs_lock(filp, fl);
674 unlock_kernel();
675 if (status < 0)
676 goto out;
677 /*
678 * Make sure we clear the cache whenever we try to get the lock.
679 * This makes locking act as a cache coherency point.
680 */
681 nfs_sync_mapping(filp->f_mapping);
682 if (!nfs_have_delegation(inode, FMODE_READ))
683 nfs_zap_caches(inode);
684 out:
685 return status;
686 }
687
688 /*
689 * Lock a (portion of) a file
690 */
691 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
692 {
693 struct inode *inode = filp->f_mapping->host;
694 int ret = -ENOLCK;
695
696 dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n",
697 filp->f_path.dentry->d_parent->d_name.name,
698 filp->f_path.dentry->d_name.name,
699 fl->fl_type, fl->fl_flags,
700 (long long)fl->fl_start, (long long)fl->fl_end);
701
702 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
703
704 /* No mandatory locks over NFS */
705 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
706 goto out_err;
707
708 if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
709 ret = NFS_PROTO(inode)->lock_check_bounds(fl);
710 if (ret < 0)
711 goto out_err;
712 }
713
714 if (IS_GETLK(cmd))
715 ret = do_getlk(filp, cmd, fl);
716 else if (fl->fl_type == F_UNLCK)
717 ret = do_unlk(filp, cmd, fl);
718 else
719 ret = do_setlk(filp, cmd, fl);
720 out_err:
721 return ret;
722 }
723
724 /*
725 * Lock a (portion of) a file
726 */
727 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
728 {
729 dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n",
730 filp->f_path.dentry->d_parent->d_name.name,
731 filp->f_path.dentry->d_name.name,
732 fl->fl_type, fl->fl_flags);
733
734 if (!(fl->fl_flags & FL_FLOCK))
735 return -ENOLCK;
736
737 /* We're simulating flock() locks using posix locks on the server */
738 fl->fl_owner = (fl_owner_t)filp;
739 fl->fl_start = 0;
740 fl->fl_end = OFFSET_MAX;
741
742 if (fl->fl_type == F_UNLCK)
743 return do_unlk(filp, cmd, fl);
744 return do_setlk(filp, cmd, fl);
745 }
746
747 /*
748 * There is no protocol support for leases, so we have no way to implement
749 * them correctly in the face of opens by other clients.
750 */
751 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
752 {
753 dprintk("NFS: setlease(%s/%s, arg=%ld)\n",
754 file->f_path.dentry->d_parent->d_name.name,
755 file->f_path.dentry->d_name.name, arg);
756
757 return -EINVAL;
758 }