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switch generic_file_splice_read() to use of ->read_iter()
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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
ddda8e0a 19#include <linux/module.h>
1da177e4
LT
20#include <linux/time.h>
21#include <linux/kernel.h>
22#include <linux/errno.h>
23#include <linux/fcntl.h>
24#include <linux/stat.h>
25#include <linux/nfs_fs.h>
26#include <linux/nfs_mount.h>
27#include <linux/mm.h>
1da177e4 28#include <linux/pagemap.h>
5a0e3ad6 29#include <linux/gfp.h>
b608b283 30#include <linux/swap.h>
1da177e4
LT
31
32#include <asm/uaccess.h>
1da177e4
LT
33
34#include "delegation.h"
94387fb1 35#include "internal.h"
91d5b470 36#include "iostat.h"
545db45f 37#include "fscache.h"
612aa983 38#include "pnfs.h"
1da177e4 39
f4ce1299
TM
40#include "nfstrace.h"
41
1da177e4
LT
42#define NFSDBG_FACILITY NFSDBG_FILE
43
f0f37e2f 44static const struct vm_operations_struct nfs_file_vm_ops;
94387fb1 45
1da177e4
LT
46/* Hack for future NFS swap support */
47#ifndef IS_SWAPFILE
48# define IS_SWAPFILE(inode) (0)
49#endif
50
ce4ef7c0 51int nfs_check_flags(int flags)
1da177e4
LT
52{
53 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
54 return -EINVAL;
55
56 return 0;
57}
89d77c8f 58EXPORT_SYMBOL_GPL(nfs_check_flags);
1da177e4
LT
59
60/*
61 * Open file
62 */
63static int
64nfs_file_open(struct inode *inode, struct file *filp)
65{
1da177e4
LT
66 int res;
67
6de1472f 68 dprintk("NFS: open file(%pD2)\n", filp);
cc0dd2d1 69
c2459dc4 70 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
1da177e4
LT
71 res = nfs_check_flags(filp->f_flags);
72 if (res)
73 return res;
74
46cb650c 75 res = nfs_open(inode, filp);
1da177e4
LT
76 return res;
77}
78
ce4ef7c0 79int
1da177e4
LT
80nfs_file_release(struct inode *inode, struct file *filp)
81{
6de1472f 82 dprintk("NFS: release(%pD2)\n", filp);
6da24bc9 83
91d5b470 84 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
aff8d8dc
AS
85 nfs_file_clear_open_context(filp);
86 return 0;
1da177e4 87}
89d77c8f 88EXPORT_SYMBOL_GPL(nfs_file_release);
1da177e4 89
980802e3
TM
90/**
91 * nfs_revalidate_size - Revalidate the file size
92 * @inode - pointer to inode struct
93 * @file - pointer to struct file
94 *
95 * Revalidates the file length. This is basically a wrapper around
96 * nfs_revalidate_inode() that takes into account the fact that we may
97 * have cached writes (in which case we don't care about the server's
98 * idea of what the file length is), or O_DIRECT (in which case we
99 * shouldn't trust the cache).
100 */
101static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
102{
103 struct nfs_server *server = NFS_SERVER(inode);
104 struct nfs_inode *nfsi = NFS_I(inode);
105
d7cf8dd0
TM
106 if (nfs_have_delegated_attributes(inode))
107 goto out_noreval;
108
980802e3
TM
109 if (filp->f_flags & O_DIRECT)
110 goto force_reval;
d7cf8dd0
TM
111 if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
112 goto force_reval;
113 if (nfs_attribute_timeout(inode))
114 goto force_reval;
115out_noreval:
116 return 0;
980802e3
TM
117force_reval:
118 return __nfs_revalidate_inode(server, inode);
119}
120
965c8e59 121loff_t nfs_file_llseek(struct file *filp, loff_t offset, int whence)
980802e3 122{
6de1472f
AV
123 dprintk("NFS: llseek file(%pD2, %lld, %d)\n",
124 filp, offset, whence);
b84e06c5 125
06222e49 126 /*
965c8e59 127 * whence == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate
06222e49
JB
128 * the cached file length
129 */
965c8e59 130 if (whence != SEEK_SET && whence != SEEK_CUR) {
980802e3 131 struct inode *inode = filp->f_mapping->host;
d5e66348 132
980802e3
TM
133 int retval = nfs_revalidate_file_size(inode, filp);
134 if (retval < 0)
135 return (loff_t)retval;
79835a71 136 }
d5e66348 137
965c8e59 138 return generic_file_llseek(filp, offset, whence);
980802e3 139}
89d77c8f 140EXPORT_SYMBOL_GPL(nfs_file_llseek);
980802e3 141
1da177e4
LT
142/*
143 * Flush all dirty pages, and check for write errors.
1da177e4 144 */
5445b1fb 145static int
75e1fcc0 146nfs_file_flush(struct file *file, fl_owner_t id)
1da177e4 147{
6de1472f 148 struct inode *inode = file_inode(file);
1da177e4 149
6de1472f 150 dprintk("NFS: flush(%pD2)\n", file);
1da177e4 151
c2459dc4 152 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
1da177e4
LT
153 if ((file->f_mode & FMODE_WRITE) == 0)
154 return 0;
7b159fc1 155
7fe5c398 156 /* Flush writes to the server and return any errors */
af7fa165 157 return vfs_fsync(file, 0);
1da177e4
LT
158}
159
ce4ef7c0 160ssize_t
3aa2d199 161nfs_file_read(struct kiocb *iocb, struct iov_iter *to)
1da177e4 162{
6de1472f 163 struct inode *inode = file_inode(iocb->ki_filp);
1da177e4
LT
164 ssize_t result;
165
2ba48ce5 166 if (iocb->ki_flags & IOCB_DIRECT)
c8b8e32d 167 return nfs_file_direct_read(iocb, to);
1da177e4 168
619d30b4 169 dprintk("NFS: read(%pD2, %zu@%lu)\n",
6de1472f 170 iocb->ki_filp,
3aa2d199 171 iov_iter_count(to), (unsigned long) iocb->ki_pos);
1da177e4 172
a5864c99
TM
173 nfs_start_io_read(inode);
174 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
4184dcf2 175 if (!result) {
3aa2d199 176 result = generic_file_read_iter(iocb, to);
4184dcf2
CL
177 if (result > 0)
178 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result);
179 }
a5864c99 180 nfs_end_io_read(inode);
1da177e4
LT
181 return result;
182}
89d77c8f 183EXPORT_SYMBOL_GPL(nfs_file_read);
1da177e4 184
ce4ef7c0 185int
1da177e4
LT
186nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
187{
6de1472f 188 struct inode *inode = file_inode(file);
1da177e4
LT
189 int status;
190
6de1472f 191 dprintk("NFS: mmap(%pD2)\n", file);
1da177e4 192
e1ebfd33
TM
193 /* Note: generic_file_mmap() returns ENOSYS on nommu systems
194 * so we call that before revalidating the mapping
195 */
196 status = generic_file_mmap(file, vma);
94387fb1
TM
197 if (!status) {
198 vma->vm_ops = &nfs_file_vm_ops;
e1ebfd33 199 status = nfs_revalidate_mapping(inode, file->f_mapping);
94387fb1 200 }
1da177e4
LT
201 return status;
202}
89d77c8f 203EXPORT_SYMBOL_GPL(nfs_file_mmap);
1da177e4
LT
204
205/*
206 * Flush any dirty pages for this process, and check for write errors.
207 * The return status from this call provides a reliable indication of
208 * whether any write errors occurred for this process.
af7fa165
TM
209 *
210 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
211 * disk, but it retrieves and clears ctx->error after synching, despite
212 * the two being set at the same time in nfs_context_set_write_error().
213 * This is because the former is used to notify the _next_ call to
25985edc 214 * nfs_file_write() that a write error occurred, and hence cause it to
af7fa165 215 * fall back to doing a synchronous write.
1da177e4 216 */
4ff79bc7 217static int
a5c58892 218nfs_file_fsync_commit(struct file *file, loff_t start, loff_t end, int datasync)
1da177e4 219{
cd3758e3 220 struct nfs_open_context *ctx = nfs_file_open_context(file);
6de1472f 221 struct inode *inode = file_inode(file);
05990d1b 222 int have_error, do_resend, status;
af7fa165
TM
223 int ret = 0;
224
6de1472f 225 dprintk("NFS: fsync file(%pD2) datasync %d\n", file, datasync);
1da177e4 226
91d5b470 227 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
05990d1b 228 do_resend = test_and_clear_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags);
af7fa165
TM
229 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
230 status = nfs_commit_inode(inode, FLUSH_SYNC);
231 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
05990d1b 232 if (have_error) {
af7fa165 233 ret = xchg(&ctx->error, 0);
05990d1b
TM
234 if (ret)
235 goto out;
236 }
237 if (status < 0) {
af7fa165 238 ret = status;
05990d1b
TM
239 goto out;
240 }
241 do_resend |= test_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags);
242 if (do_resend)
243 ret = -EAGAIN;
244out:
a5c58892
BS
245 return ret;
246}
247
4ff79bc7 248int
a5c58892
BS
249nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
250{
251 int ret;
496ad9aa 252 struct inode *inode = file_inode(file);
a5c58892 253
f4ce1299
TM
254 trace_nfs_fsync_enter(inode);
255
05990d1b
TM
256 do {
257 ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
258 if (ret != 0)
259 break;
05990d1b 260 ret = nfs_file_fsync_commit(file, start, end, datasync);
4ff79bc7
CH
261 if (!ret)
262 ret = pnfs_sync_inode(inode, !!datasync);
dcfc4f25
TM
263 /*
264 * If nfs_file_fsync_commit detected a server reboot, then
265 * resend all dirty pages that might have been covered by
266 * the NFS_CONTEXT_RESEND_WRITES flag
267 */
268 start = 0;
269 end = LLONG_MAX;
05990d1b
TM
270 } while (ret == -EAGAIN);
271
f4ce1299 272 trace_nfs_fsync_exit(inode, ret);
af7fa165 273 return ret;
1da177e4 274}
4ff79bc7 275EXPORT_SYMBOL_GPL(nfs_file_fsync);
1da177e4 276
38c73044
PS
277/*
278 * Decide whether a read/modify/write cycle may be more efficient
279 * then a modify/write/read cycle when writing to a page in the
280 * page cache.
281 *
282 * The modify/write/read cycle may occur if a page is read before
283 * being completely filled by the writer. In this situation, the
284 * page must be completely written to stable storage on the server
285 * before it can be refilled by reading in the page from the server.
286 * This can lead to expensive, small, FILE_SYNC mode writes being
287 * done.
288 *
289 * It may be more efficient to read the page first if the file is
290 * open for reading in addition to writing, the page is not marked
291 * as Uptodate, it is not dirty or waiting to be committed,
292 * indicating that it was previously allocated and then modified,
293 * that there were valid bytes of data in that range of the file,
294 * and that the new data won't completely replace the old data in
295 * that range of the file.
296 */
297static int nfs_want_read_modify_write(struct file *file, struct page *page,
298 loff_t pos, unsigned len)
299{
300 unsigned int pglen = nfs_page_length(page);
09cbfeaf 301 unsigned int offset = pos & (PAGE_SIZE - 1);
38c73044
PS
302 unsigned int end = offset + len;
303
612aa983
CH
304 if (pnfs_ld_read_whole_page(file->f_mapping->host)) {
305 if (!PageUptodate(page))
306 return 1;
307 return 0;
308 }
309
38c73044
PS
310 if ((file->f_mode & FMODE_READ) && /* open for read? */
311 !PageUptodate(page) && /* Uptodate? */
312 !PagePrivate(page) && /* i/o request already? */
313 pglen && /* valid bytes of file? */
314 (end < pglen || offset)) /* replace all valid bytes? */
315 return 1;
316 return 0;
317}
318
1da177e4 319/*
4899f9c8
NP
320 * This does the "real" work of the write. We must allocate and lock the
321 * page to be sent back to the generic routine, which then copies the
322 * data from user space.
1da177e4
LT
323 *
324 * If the writer ends up delaying the write, the writer needs to
325 * increment the page use counts until he is done with the page.
326 */
4899f9c8
NP
327static int nfs_write_begin(struct file *file, struct address_space *mapping,
328 loff_t pos, unsigned len, unsigned flags,
329 struct page **pagep, void **fsdata)
1da177e4 330{
4899f9c8 331 int ret;
09cbfeaf 332 pgoff_t index = pos >> PAGE_SHIFT;
4899f9c8 333 struct page *page;
38c73044 334 int once_thru = 0;
4899f9c8 335
1e8968c5 336 dfprintk(PAGECACHE, "NFS: write_begin(%pD2(%lu), %u@%lld)\n",
6de1472f 337 file, mapping->host->i_ino, len, (long long) pos);
b7eaefaa 338
38c73044 339start:
54566b2c 340 page = grab_cache_page_write_begin(mapping, index, flags);
4899f9c8
NP
341 if (!page)
342 return -ENOMEM;
343 *pagep = page;
344
345 ret = nfs_flush_incompatible(file, page);
346 if (ret) {
347 unlock_page(page);
09cbfeaf 348 put_page(page);
38c73044
PS
349 } else if (!once_thru &&
350 nfs_want_read_modify_write(file, page, pos, len)) {
351 once_thru = 1;
352 ret = nfs_readpage(file, page);
09cbfeaf 353 put_page(page);
38c73044
PS
354 if (!ret)
355 goto start;
4899f9c8
NP
356 }
357 return ret;
1da177e4
LT
358}
359
4899f9c8
NP
360static int nfs_write_end(struct file *file, struct address_space *mapping,
361 loff_t pos, unsigned len, unsigned copied,
362 struct page *page, void *fsdata)
1da177e4 363{
09cbfeaf 364 unsigned offset = pos & (PAGE_SIZE - 1);
dc24826b 365 struct nfs_open_context *ctx = nfs_file_open_context(file);
4899f9c8 366 int status;
1da177e4 367
1e8968c5 368 dfprintk(PAGECACHE, "NFS: write_end(%pD2(%lu), %u@%lld)\n",
6de1472f 369 file, mapping->host->i_ino, len, (long long) pos);
b7eaefaa 370
efc91ed0
TM
371 /*
372 * Zero any uninitialised parts of the page, and then mark the page
373 * as up to date if it turns out that we're extending the file.
374 */
375 if (!PageUptodate(page)) {
376 unsigned pglen = nfs_page_length(page);
377 unsigned end = offset + len;
378
379 if (pglen == 0) {
380 zero_user_segments(page, 0, offset,
09cbfeaf 381 end, PAGE_SIZE);
efc91ed0
TM
382 SetPageUptodate(page);
383 } else if (end >= pglen) {
09cbfeaf 384 zero_user_segment(page, end, PAGE_SIZE);
efc91ed0
TM
385 if (offset == 0)
386 SetPageUptodate(page);
387 } else
09cbfeaf 388 zero_user_segment(page, pglen, PAGE_SIZE);
efc91ed0
TM
389 }
390
4899f9c8 391 status = nfs_updatepage(file, page, offset, copied);
4899f9c8
NP
392
393 unlock_page(page);
09cbfeaf 394 put_page(page);
4899f9c8 395
3d509e54
CL
396 if (status < 0)
397 return status;
2701d086 398 NFS_I(mapping->host)->write_io += copied;
dc24826b 399
ce52914e 400 if (nfs_ctx_key_to_expire(ctx, mapping->host)) {
dc24826b
AA
401 status = nfs_wb_all(mapping->host);
402 if (status < 0)
403 return status;
404 }
405
3d509e54 406 return copied;
1da177e4
LT
407}
408
6b9b3514
DH
409/*
410 * Partially or wholly invalidate a page
411 * - Release the private state associated with a page if undergoing complete
412 * page invalidation
545db45f 413 * - Called if either PG_private or PG_fscache is set on the page
6b9b3514
DH
414 * - Caller holds page lock
415 */
d47992f8
LC
416static void nfs_invalidate_page(struct page *page, unsigned int offset,
417 unsigned int length)
cd52ed35 418{
d47992f8
LC
419 dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %u, %u)\n",
420 page, offset, length);
b7eaefaa 421
09cbfeaf 422 if (offset != 0 || length < PAGE_SIZE)
1c75950b 423 return;
d2ccddf0 424 /* Cancel any unstarted writes on this page */
d56b4ddf 425 nfs_wb_page_cancel(page_file_mapping(page)->host, page);
545db45f
DH
426
427 nfs_fscache_invalidate_page(page, page->mapping->host);
cd52ed35
TM
428}
429
6b9b3514
DH
430/*
431 * Attempt to release the private state associated with a page
545db45f 432 * - Called if either PG_private or PG_fscache is set on the page
6b9b3514
DH
433 * - Caller holds page lock
434 * - Return true (may release page) or false (may not)
435 */
cd52ed35
TM
436static int nfs_release_page(struct page *page, gfp_t gfp)
437{
b7eaefaa
CL
438 dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
439
e3db7691 440 /* If PagePrivate() is set, then the page is not freeable */
545db45f
DH
441 if (PagePrivate(page))
442 return 0;
443 return nfs_fscache_release_page(page, gfp);
e3db7691
TM
444}
445
f919b196
MG
446static void nfs_check_dirty_writeback(struct page *page,
447 bool *dirty, bool *writeback)
448{
449 struct nfs_inode *nfsi;
450 struct address_space *mapping = page_file_mapping(page);
451
452 if (!mapping || PageSwapCache(page))
453 return;
454
455 /*
456 * Check if an unstable page is currently being committed and
457 * if so, have the VM treat it as if the page is under writeback
458 * so it will not block due to pages that will shortly be freeable.
459 */
460 nfsi = NFS_I(mapping->host);
af7cf057 461 if (atomic_read(&nfsi->commit_info.rpcs_out)) {
f919b196
MG
462 *writeback = true;
463 return;
464 }
465
466 /*
467 * If PagePrivate() is set, then the page is not freeable and as the
468 * inode is not being committed, it's not going to be cleaned in the
469 * near future so treat it as dirty
470 */
471 if (PagePrivate(page))
472 *dirty = true;
473}
474
6b9b3514
DH
475/*
476 * Attempt to clear the private state associated with a page when an error
477 * occurs that requires the cached contents of an inode to be written back or
478 * destroyed
545db45f 479 * - Called if either PG_private or fscache is set on the page
6b9b3514
DH
480 * - Caller holds page lock
481 * - Return 0 if successful, -error otherwise
482 */
e3db7691
TM
483static int nfs_launder_page(struct page *page)
484{
d56b4ddf 485 struct inode *inode = page_file_mapping(page)->host;
545db45f 486 struct nfs_inode *nfsi = NFS_I(inode);
b7eaefaa
CL
487
488 dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
489 inode->i_ino, (long long)page_offset(page));
490
545db45f 491 nfs_fscache_wait_on_page_write(nfsi, page);
d6c843b9 492 return nfs_wb_launder_page(inode, page);
cd52ed35
TM
493}
494
a564b8f0
MG
495static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file,
496 sector_t *span)
497{
dad2b015
JL
498 struct rpc_clnt *clnt = NFS_CLIENT(file->f_mapping->host);
499
a564b8f0 500 *span = sis->pages;
dad2b015 501
3c87ef6e 502 return rpc_clnt_swap_activate(clnt);
a564b8f0
MG
503}
504
505static void nfs_swap_deactivate(struct file *file)
506{
dad2b015
JL
507 struct rpc_clnt *clnt = NFS_CLIENT(file->f_mapping->host);
508
3c87ef6e 509 rpc_clnt_swap_deactivate(clnt);
a564b8f0 510}
a564b8f0 511
f5e54d6e 512const struct address_space_operations nfs_file_aops = {
1da177e4
LT
513 .readpage = nfs_readpage,
514 .readpages = nfs_readpages,
9cccef95 515 .set_page_dirty = __set_page_dirty_nobuffers,
1da177e4
LT
516 .writepage = nfs_writepage,
517 .writepages = nfs_writepages,
4899f9c8
NP
518 .write_begin = nfs_write_begin,
519 .write_end = nfs_write_end,
cd52ed35
TM
520 .invalidatepage = nfs_invalidate_page,
521 .releasepage = nfs_release_page,
1da177e4 522 .direct_IO = nfs_direct_IO,
074cc1de 523 .migratepage = nfs_migrate_page,
e3db7691 524 .launder_page = nfs_launder_page,
f919b196 525 .is_dirty_writeback = nfs_check_dirty_writeback,
f590f333 526 .error_remove_page = generic_error_remove_page,
a564b8f0
MG
527 .swap_activate = nfs_swap_activate,
528 .swap_deactivate = nfs_swap_deactivate,
1da177e4
LT
529};
530
6b9b3514
DH
531/*
532 * Notification that a PTE pointing to an NFS page is about to be made
533 * writable, implying that someone is about to modify the page through a
534 * shared-writable mapping
535 */
c2ec175c 536static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
94387fb1 537{
c2ec175c 538 struct page *page = vmf->page;
94387fb1 539 struct file *filp = vma->vm_file;
6de1472f 540 struct inode *inode = file_inode(filp);
94387fb1 541 unsigned pagelen;
bc4866b6 542 int ret = VM_FAULT_NOPAGE;
4899f9c8 543 struct address_space *mapping;
94387fb1 544
1e8968c5 545 dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%pD2(%lu), offset %lld)\n",
6de1472f 546 filp, filp->f_mapping->host->i_ino,
b7eaefaa
CL
547 (long long)page_offset(page));
548
9a773e7c
TM
549 sb_start_pagefault(inode->i_sb);
550
545db45f 551 /* make sure the cache has finished storing the page */
6de1472f 552 nfs_fscache_wait_on_page_write(NFS_I(inode), page);
545db45f 553
ef070dcb
TM
554 wait_on_bit_action(&NFS_I(inode)->flags, NFS_INO_INVALIDATING,
555 nfs_wait_bit_killable, TASK_KILLABLE);
556
94387fb1 557 lock_page(page);
d56b4ddf 558 mapping = page_file_mapping(page);
6de1472f 559 if (mapping != inode->i_mapping)
8b1f9ee5
TM
560 goto out_unlock;
561
2aeb98f4
TM
562 wait_on_page_writeback(page);
563
94387fb1 564 pagelen = nfs_page_length(page);
8b1f9ee5
TM
565 if (pagelen == 0)
566 goto out_unlock;
4899f9c8 567
bc4866b6
TM
568 ret = VM_FAULT_LOCKED;
569 if (nfs_flush_incompatible(filp, page) == 0 &&
570 nfs_updatepage(filp, page, 0, pagelen) == 0)
571 goto out;
8b1f9ee5 572
bc4866b6 573 ret = VM_FAULT_SIGBUS;
8b1f9ee5
TM
574out_unlock:
575 unlock_page(page);
bc4866b6 576out:
9a773e7c 577 sb_end_pagefault(inode->i_sb);
bc4866b6 578 return ret;
94387fb1
TM
579}
580
f0f37e2f 581static const struct vm_operations_struct nfs_file_vm_ops = {
94387fb1 582 .fault = filemap_fault,
f1820361 583 .map_pages = filemap_map_pages,
94387fb1
TM
584 .page_mkwrite = nfs_vm_page_mkwrite,
585};
586
7e94d6c4 587static int nfs_need_check_write(struct file *filp, struct inode *inode)
7b159fc1
TM
588{
589 struct nfs_open_context *ctx;
590
cd3758e3 591 ctx = nfs_file_open_context(filp);
dc24826b 592 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags) ||
ce52914e 593 nfs_ctx_key_to_expire(ctx, inode))
7b159fc1
TM
594 return 1;
595 return 0;
596}
597
edaf4369 598ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from)
1da177e4 599{
6de1472f
AV
600 struct file *file = iocb->ki_filp;
601 struct inode *inode = file_inode(file);
7e381172 602 unsigned long written = 0;
1da177e4
LT
603 ssize_t result;
604
6de1472f 605 result = nfs_key_timeout_notify(file, inode);
dc24826b
AA
606 if (result)
607 return result;
608
89698b24 609 if (iocb->ki_flags & IOCB_DIRECT)
65a4a1ca 610 return nfs_file_direct_write(iocb, from);
1da177e4 611
619d30b4 612 dprintk("NFS: write(%pD2, %zu@%Ld)\n",
18290650 613 file, iov_iter_count(from), (long long) iocb->ki_pos);
1da177e4 614
1da177e4
LT
615 if (IS_SWAPFILE(inode))
616 goto out_swapfile;
7d52e862
TM
617 /*
618 * O_APPEND implies that we must revalidate the file length.
619 */
2ba48ce5 620 if (iocb->ki_flags & IOCB_APPEND) {
6de1472f 621 result = nfs_revalidate_file_size(inode, file);
7d52e862
TM
622 if (result)
623 goto out;
fe51beec 624 }
1da177e4 625
a5864c99 626 nfs_start_io_write(inode);
18290650
TM
627 result = generic_write_checks(iocb, from);
628 if (result > 0) {
629 current->backing_dev_info = inode_to_bdi(inode);
630 result = generic_perform_write(file, from, iocb->ki_pos);
631 current->backing_dev_info = NULL;
632 }
a5864c99 633 nfs_end_io_write(inode);
18290650 634 if (result <= 0)
1da177e4
LT
635 goto out;
636
c49edecd
TM
637 result = generic_write_sync(iocb, result);
638 if (result < 0)
639 goto out;
640 written = result;
18290650 641 iocb->ki_pos += written;
7e381172 642
7e94d6c4 643 /* Return error values */
18290650 644 if (nfs_need_check_write(file, inode)) {
6de1472f 645 int err = vfs_fsync(file, 0);
200baa21
TM
646 if (err < 0)
647 result = err;
648 }
18290650 649 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
1da177e4
LT
650out:
651 return result;
652
653out_swapfile:
654 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
18290650 655 return -EBUSY;
1da177e4 656}
89d77c8f 657EXPORT_SYMBOL_GPL(nfs_file_write);
1da177e4 658
5eebde23
SJ
659static int
660do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
1da177e4
LT
661{
662 struct inode *inode = filp->f_mapping->host;
663 int status = 0;
21ac19d4 664 unsigned int saved_type = fl->fl_type;
1da177e4 665
039c4d7a 666 /* Try local locking first */
6d34ac19
BF
667 posix_test_lock(filp, fl);
668 if (fl->fl_type != F_UNLCK) {
669 /* found a conflict */
039c4d7a 670 goto out;
1da177e4 671 }
21ac19d4 672 fl->fl_type = saved_type;
039c4d7a 673
011e2a7f 674 if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
039c4d7a
TM
675 goto out_noconflict;
676
5eebde23 677 if (is_local)
039c4d7a
TM
678 goto out_noconflict;
679
680 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
681out:
1da177e4 682 return status;
039c4d7a
TM
683out_noconflict:
684 fl->fl_type = F_UNLCK;
685 goto out;
1da177e4
LT
686}
687
688static int do_vfs_lock(struct file *file, struct file_lock *fl)
689{
4f656367 690 return locks_lock_file_wait(file, fl);
1da177e4
LT
691}
692
5eebde23
SJ
693static int
694do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
1da177e4
LT
695{
696 struct inode *inode = filp->f_mapping->host;
7a8203d8 697 struct nfs_lock_context *l_ctx;
1da177e4
LT
698 int status;
699
1da177e4
LT
700 /*
701 * Flush all pending writes before doing anything
702 * with locks..
703 */
d9dabc1a 704 vfs_fsync(filp, 0);
1da177e4 705
7a8203d8
TM
706 l_ctx = nfs_get_lock_context(nfs_file_open_context(filp));
707 if (!IS_ERR(l_ctx)) {
210c7c17 708 status = nfs_iocounter_wait(l_ctx);
7a8203d8
TM
709 nfs_put_lock_context(l_ctx);
710 if (status < 0)
711 return status;
712 }
713
1da177e4
LT
714 /* NOTE: special case
715 * If we're signalled while cleaning up locks on process exit, we
716 * still need to complete the unlock.
717 */
5eebde23
SJ
718 /*
719 * Use local locking if mounted with "-onolock" or with appropriate
720 * "-olocal_lock="
721 */
722 if (!is_local)
1da177e4
LT
723 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
724 else
725 status = do_vfs_lock(filp, fl);
1da177e4
LT
726 return status;
727}
728
5eebde23
SJ
729static int
730do_setlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
1da177e4
LT
731{
732 struct inode *inode = filp->f_mapping->host;
1da177e4
LT
733 int status;
734
1da177e4
LT
735 /*
736 * Flush all pending writes before doing anything
737 * with locks..
738 */
29884df0
TM
739 status = nfs_sync_mapping(filp->f_mapping);
740 if (status != 0)
1da177e4
LT
741 goto out;
742
5eebde23
SJ
743 /*
744 * Use local locking if mounted with "-onolock" or with appropriate
745 * "-olocal_lock="
746 */
747 if (!is_local)
1da177e4 748 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
c4d7c402 749 else
1da177e4 750 status = do_vfs_lock(filp, fl);
1da177e4
LT
751 if (status < 0)
752 goto out;
6b96724e 753
1da177e4 754 /*
6b96724e
RL
755 * Revalidate the cache if the server has time stamps granular
756 * enough to detect subsecond changes. Otherwise, clear the
757 * cache to prevent missing any changes.
758 *
1da177e4
LT
759 * This makes locking act as a cache coherency point.
760 */
29884df0 761 nfs_sync_mapping(filp->f_mapping);
ca0daa27
TM
762 if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
763 nfs_zap_mapping(inode, filp->f_mapping);
1da177e4 764out:
1da177e4
LT
765 return status;
766}
767
768/*
769 * Lock a (portion of) a file
770 */
ce4ef7c0 771int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
1da177e4 772{
6da24bc9 773 struct inode *inode = filp->f_mapping->host;
2116271a 774 int ret = -ENOLCK;
5eebde23 775 int is_local = 0;
1da177e4 776
6de1472f
AV
777 dprintk("NFS: lock(%pD2, t=%x, fl=%x, r=%lld:%lld)\n",
778 filp, fl->fl_type, fl->fl_flags,
1da177e4 779 (long long)fl->fl_start, (long long)fl->fl_end);
6da24bc9 780
91d5b470 781 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
1da177e4
LT
782
783 /* No mandatory locks over NFS */
dfad9441 784 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
2116271a
TM
785 goto out_err;
786
5eebde23
SJ
787 if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FCNTL)
788 is_local = 1;
789
2116271a
TM
790 if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
791 ret = NFS_PROTO(inode)->lock_check_bounds(fl);
792 if (ret < 0)
793 goto out_err;
794 }
1da177e4
LT
795
796 if (IS_GETLK(cmd))
5eebde23 797 ret = do_getlk(filp, cmd, fl, is_local);
2116271a 798 else if (fl->fl_type == F_UNLCK)
5eebde23 799 ret = do_unlk(filp, cmd, fl, is_local);
2116271a 800 else
5eebde23 801 ret = do_setlk(filp, cmd, fl, is_local);
2116271a
TM
802out_err:
803 return ret;
1da177e4 804}
89d77c8f 805EXPORT_SYMBOL_GPL(nfs_lock);
1da177e4
LT
806
807/*
808 * Lock a (portion of) a file
809 */
ce4ef7c0 810int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
1da177e4 811{
5eebde23
SJ
812 struct inode *inode = filp->f_mapping->host;
813 int is_local = 0;
814
6de1472f
AV
815 dprintk("NFS: flock(%pD2, t=%x, fl=%x)\n",
816 filp, fl->fl_type, fl->fl_flags);
1da177e4 817
1da177e4
LT
818 if (!(fl->fl_flags & FL_FLOCK))
819 return -ENOLCK;
820
ad0fcd4e
JL
821 /*
822 * The NFSv4 protocol doesn't support LOCK_MAND, which is not part of
823 * any standard. In principle we might be able to support LOCK_MAND
824 * on NFSv2/3 since NLMv3/4 support DOS share modes, but for now the
825 * NFS code is not set up for it.
826 */
827 if (fl->fl_type & LOCK_MAND)
828 return -EINVAL;
829
5eebde23
SJ
830 if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FLOCK)
831 is_local = 1;
832
1da177e4 833 /* We're simulating flock() locks using posix locks on the server */
1da177e4 834 if (fl->fl_type == F_UNLCK)
5eebde23
SJ
835 return do_unlk(filp, cmd, fl, is_local);
836 return do_setlk(filp, cmd, fl, is_local);
1da177e4 837}
89d77c8f 838EXPORT_SYMBOL_GPL(nfs_flock);
370f6599 839
0486958f
JL
840const struct file_operations nfs_file_operations = {
841 .llseek = nfs_file_llseek,
3aa2d199 842 .read_iter = nfs_file_read,
edaf4369 843 .write_iter = nfs_file_write,
0486958f
JL
844 .mmap = nfs_file_mmap,
845 .open = nfs_file_open,
846 .flush = nfs_file_flush,
847 .release = nfs_file_release,
848 .fsync = nfs_file_fsync,
849 .lock = nfs_lock,
850 .flock = nfs_flock,
82c156f8 851 .splice_read = generic_file_splice_read,
4da54c21 852 .splice_write = iter_file_splice_write,
0486958f 853 .check_flags = nfs_check_flags,
1c994a09 854 .setlease = simple_nosetlease,
0486958f 855};
ddda8e0a 856EXPORT_SYMBOL_GPL(nfs_file_operations);