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Commit | Line | Data |
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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" |
545db45f | 38 | #include "fscache.h" |
1da177e4 LT |
39 | |
40 | #define NFSDBG_FACILITY NFSDBG_FILE | |
41 | ||
42 | static int nfs_file_open(struct inode *, struct file *); | |
43 | static int nfs_file_release(struct inode *, struct file *); | |
980802e3 | 44 | static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin); |
1da177e4 | 45 | static int nfs_file_mmap(struct file *, struct vm_area_struct *); |
f0930fff JA |
46 | static ssize_t nfs_file_splice_read(struct file *filp, loff_t *ppos, |
47 | struct pipe_inode_info *pipe, | |
48 | size_t count, unsigned int flags); | |
027445c3 BP |
49 | static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov, |
50 | unsigned long nr_segs, loff_t pos); | |
51 | static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov, | |
52 | unsigned long nr_segs, loff_t pos); | |
75e1fcc0 | 53 | static int nfs_file_flush(struct file *, fl_owner_t id); |
54917786 | 54 | static int nfs_file_fsync(struct file *, struct dentry *dentry, int datasync); |
1da177e4 LT |
55 | static int nfs_check_flags(int flags); |
56 | static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl); | |
57 | static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl); | |
370f6599 | 58 | static int nfs_setlease(struct file *file, long arg, struct file_lock **fl); |
1da177e4 | 59 | |
94387fb1 TM |
60 | static struct vm_operations_struct nfs_file_vm_ops; |
61 | ||
4b6f5d20 | 62 | const struct file_operations nfs_file_operations = { |
980802e3 | 63 | .llseek = nfs_file_llseek, |
1da177e4 LT |
64 | .read = do_sync_read, |
65 | .write = do_sync_write, | |
027445c3 BP |
66 | .aio_read = nfs_file_read, |
67 | .aio_write = nfs_file_write, | |
1da177e4 LT |
68 | .mmap = nfs_file_mmap, |
69 | .open = nfs_file_open, | |
70 | .flush = nfs_file_flush, | |
71 | .release = nfs_file_release, | |
54917786 | 72 | .fsync = nfs_file_fsync, |
1da177e4 LT |
73 | .lock = nfs_lock, |
74 | .flock = nfs_flock, | |
f0930fff | 75 | .splice_read = nfs_file_splice_read, |
1da177e4 | 76 | .check_flags = nfs_check_flags, |
370f6599 | 77 | .setlease = nfs_setlease, |
1da177e4 LT |
78 | }; |
79 | ||
92e1d5be | 80 | const struct inode_operations nfs_file_inode_operations = { |
1da177e4 LT |
81 | .permission = nfs_permission, |
82 | .getattr = nfs_getattr, | |
83 | .setattr = nfs_setattr, | |
84 | }; | |
85 | ||
b7fa0554 | 86 | #ifdef CONFIG_NFS_V3 |
92e1d5be | 87 | const struct inode_operations nfs3_file_inode_operations = { |
b7fa0554 AG |
88 | .permission = nfs_permission, |
89 | .getattr = nfs_getattr, | |
90 | .setattr = nfs_setattr, | |
91 | .listxattr = nfs3_listxattr, | |
92 | .getxattr = nfs3_getxattr, | |
93 | .setxattr = nfs3_setxattr, | |
94 | .removexattr = nfs3_removexattr, | |
95 | }; | |
96 | #endif /* CONFIG_NFS_v3 */ | |
97 | ||
1da177e4 LT |
98 | /* Hack for future NFS swap support */ |
99 | #ifndef IS_SWAPFILE | |
100 | # define IS_SWAPFILE(inode) (0) | |
101 | #endif | |
102 | ||
103 | static int nfs_check_flags(int flags) | |
104 | { | |
105 | if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT)) | |
106 | return -EINVAL; | |
107 | ||
108 | return 0; | |
109 | } | |
110 | ||
111 | /* | |
112 | * Open file | |
113 | */ | |
114 | static int | |
115 | nfs_file_open(struct inode *inode, struct file *filp) | |
116 | { | |
1da177e4 LT |
117 | int res; |
118 | ||
6da24bc9 | 119 | dprintk("NFS: open file(%s/%s)\n", |
cc0dd2d1 CL |
120 | filp->f_path.dentry->d_parent->d_name.name, |
121 | filp->f_path.dentry->d_name.name); | |
122 | ||
1da177e4 LT |
123 | res = nfs_check_flags(filp->f_flags); |
124 | if (res) | |
125 | return res; | |
126 | ||
91d5b470 | 127 | nfs_inc_stats(inode, NFSIOS_VFSOPEN); |
46cb650c | 128 | res = nfs_open(inode, filp); |
1da177e4 LT |
129 | return res; |
130 | } | |
131 | ||
132 | static int | |
133 | nfs_file_release(struct inode *inode, struct file *filp) | |
134 | { | |
6da24bc9 CL |
135 | struct dentry *dentry = filp->f_path.dentry; |
136 | ||
137 | dprintk("NFS: release(%s/%s)\n", | |
138 | dentry->d_parent->d_name.name, | |
139 | dentry->d_name.name); | |
140 | ||
91d5b470 | 141 | nfs_inc_stats(inode, NFSIOS_VFSRELEASE); |
46cb650c | 142 | return nfs_release(inode, filp); |
1da177e4 LT |
143 | } |
144 | ||
980802e3 TM |
145 | /** |
146 | * nfs_revalidate_size - Revalidate the file size | |
147 | * @inode - pointer to inode struct | |
148 | * @file - pointer to struct file | |
149 | * | |
150 | * Revalidates the file length. This is basically a wrapper around | |
151 | * nfs_revalidate_inode() that takes into account the fact that we may | |
152 | * have cached writes (in which case we don't care about the server's | |
153 | * idea of what the file length is), or O_DIRECT (in which case we | |
154 | * shouldn't trust the cache). | |
155 | */ | |
156 | static int nfs_revalidate_file_size(struct inode *inode, struct file *filp) | |
157 | { | |
158 | struct nfs_server *server = NFS_SERVER(inode); | |
159 | struct nfs_inode *nfsi = NFS_I(inode); | |
160 | ||
161 | if (server->flags & NFS_MOUNT_NOAC) | |
162 | goto force_reval; | |
163 | if (filp->f_flags & O_DIRECT) | |
164 | goto force_reval; | |
165 | if (nfsi->npages != 0) | |
166 | return 0; | |
55296809 | 167 | if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode)) |
fe51beec | 168 | return 0; |
980802e3 TM |
169 | force_reval: |
170 | return __nfs_revalidate_inode(server, inode); | |
171 | } | |
172 | ||
173 | static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin) | |
174 | { | |
9465efc9 | 175 | loff_t loff; |
e89e896d | 176 | |
6da24bc9 | 177 | dprintk("NFS: llseek file(%s/%s, %lld, %d)\n", |
b84e06c5 CL |
178 | filp->f_path.dentry->d_parent->d_name.name, |
179 | filp->f_path.dentry->d_name.name, | |
180 | offset, origin); | |
181 | ||
980802e3 | 182 | /* origin == SEEK_END => we must revalidate the cached file length */ |
aec5e175 | 183 | if (origin == SEEK_END) { |
980802e3 | 184 | struct inode *inode = filp->f_mapping->host; |
d5e66348 | 185 | |
980802e3 TM |
186 | int retval = nfs_revalidate_file_size(inode, filp); |
187 | if (retval < 0) | |
188 | return (loff_t)retval; | |
d5e66348 TM |
189 | |
190 | spin_lock(&inode->i_lock); | |
191 | loff = generic_file_llseek_unlocked(filp, offset, origin); | |
192 | spin_unlock(&inode->i_lock); | |
193 | } else | |
194 | loff = generic_file_llseek_unlocked(filp, offset, origin); | |
9465efc9 | 195 | return loff; |
980802e3 TM |
196 | } |
197 | ||
7b159fc1 | 198 | /* |
54917786 | 199 | * Helper for nfs_file_flush() and nfs_file_fsync() |
7b159fc1 TM |
200 | * |
201 | * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to | |
202 | * disk, but it retrieves and clears ctx->error after synching, despite | |
203 | * the two being set at the same time in nfs_context_set_write_error(). | |
204 | * This is because the former is used to notify the _next_ call to | |
205 | * nfs_file_write() that a write error occured, and hence cause it to | |
206 | * fall back to doing a synchronous write. | |
207 | */ | |
208 | static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode) | |
209 | { | |
210 | int have_error, status; | |
211 | int ret = 0; | |
212 | ||
213 | have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); | |
214 | status = nfs_wb_all(inode); | |
215 | have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); | |
216 | if (have_error) | |
217 | ret = xchg(&ctx->error, 0); | |
218 | if (!ret) | |
219 | ret = status; | |
220 | return ret; | |
221 | } | |
222 | ||
1da177e4 LT |
223 | /* |
224 | * Flush all dirty pages, and check for write errors. | |
1da177e4 LT |
225 | */ |
226 | static int | |
75e1fcc0 | 227 | nfs_file_flush(struct file *file, fl_owner_t id) |
1da177e4 | 228 | { |
cd3758e3 | 229 | struct nfs_open_context *ctx = nfs_file_open_context(file); |
6da24bc9 CL |
230 | struct dentry *dentry = file->f_path.dentry; |
231 | struct inode *inode = dentry->d_inode; | |
1da177e4 | 232 | |
6da24bc9 CL |
233 | dprintk("NFS: flush(%s/%s)\n", |
234 | dentry->d_parent->d_name.name, | |
235 | dentry->d_name.name); | |
1da177e4 LT |
236 | |
237 | if ((file->f_mode & FMODE_WRITE) == 0) | |
238 | return 0; | |
91d5b470 | 239 | nfs_inc_stats(inode, NFSIOS_VFSFLUSH); |
7b159fc1 | 240 | |
7fe5c398 TM |
241 | /* Flush writes to the server and return any errors */ |
242 | return nfs_do_fsync(ctx, inode); | |
1da177e4 LT |
243 | } |
244 | ||
245 | static ssize_t | |
027445c3 BP |
246 | nfs_file_read(struct kiocb *iocb, const struct iovec *iov, |
247 | unsigned long nr_segs, loff_t pos) | |
1da177e4 | 248 | { |
01cce933 | 249 | struct dentry * dentry = iocb->ki_filp->f_path.dentry; |
1da177e4 LT |
250 | struct inode * inode = dentry->d_inode; |
251 | ssize_t result; | |
027445c3 | 252 | size_t count = iov_length(iov, nr_segs); |
1da177e4 | 253 | |
1da177e4 | 254 | if (iocb->ki_filp->f_flags & O_DIRECT) |
027445c3 | 255 | return nfs_file_direct_read(iocb, iov, nr_segs, pos); |
1da177e4 | 256 | |
6da24bc9 | 257 | dprintk("NFS: read(%s/%s, %lu@%lu)\n", |
1da177e4 LT |
258 | dentry->d_parent->d_name.name, dentry->d_name.name, |
259 | (unsigned long) count, (unsigned long) pos); | |
260 | ||
44b11874 | 261 | result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping); |
91d5b470 | 262 | nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count); |
1da177e4 | 263 | if (!result) |
027445c3 | 264 | result = generic_file_aio_read(iocb, iov, nr_segs, pos); |
1da177e4 LT |
265 | return result; |
266 | } | |
267 | ||
268 | static ssize_t | |
f0930fff JA |
269 | nfs_file_splice_read(struct file *filp, loff_t *ppos, |
270 | struct pipe_inode_info *pipe, size_t count, | |
271 | unsigned int flags) | |
1da177e4 | 272 | { |
01cce933 | 273 | struct dentry *dentry = filp->f_path.dentry; |
1da177e4 LT |
274 | struct inode *inode = dentry->d_inode; |
275 | ssize_t res; | |
276 | ||
6da24bc9 | 277 | dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n", |
1da177e4 LT |
278 | dentry->d_parent->d_name.name, dentry->d_name.name, |
279 | (unsigned long) count, (unsigned long long) *ppos); | |
280 | ||
44b11874 | 281 | res = nfs_revalidate_mapping(inode, filp->f_mapping); |
1da177e4 | 282 | if (!res) |
f0930fff | 283 | res = generic_file_splice_read(filp, ppos, pipe, count, flags); |
1da177e4 LT |
284 | return res; |
285 | } | |
286 | ||
287 | static int | |
288 | nfs_file_mmap(struct file * file, struct vm_area_struct * vma) | |
289 | { | |
01cce933 | 290 | struct dentry *dentry = file->f_path.dentry; |
1da177e4 LT |
291 | struct inode *inode = dentry->d_inode; |
292 | int status; | |
293 | ||
6da24bc9 | 294 | dprintk("NFS: mmap(%s/%s)\n", |
1da177e4 LT |
295 | dentry->d_parent->d_name.name, dentry->d_name.name); |
296 | ||
e1ebfd33 TM |
297 | /* Note: generic_file_mmap() returns ENOSYS on nommu systems |
298 | * so we call that before revalidating the mapping | |
299 | */ | |
300 | status = generic_file_mmap(file, vma); | |
94387fb1 TM |
301 | if (!status) { |
302 | vma->vm_ops = &nfs_file_vm_ops; | |
e1ebfd33 | 303 | status = nfs_revalidate_mapping(inode, file->f_mapping); |
94387fb1 | 304 | } |
1da177e4 LT |
305 | return status; |
306 | } | |
307 | ||
308 | /* | |
309 | * Flush any dirty pages for this process, and check for write errors. | |
310 | * The return status from this call provides a reliable indication of | |
311 | * whether any write errors occurred for this process. | |
312 | */ | |
313 | static int | |
54917786 | 314 | nfs_file_fsync(struct file *file, struct dentry *dentry, int datasync) |
1da177e4 | 315 | { |
cd3758e3 | 316 | struct nfs_open_context *ctx = nfs_file_open_context(file); |
1da177e4 | 317 | struct inode *inode = dentry->d_inode; |
1da177e4 | 318 | |
6da24bc9 | 319 | dprintk("NFS: fsync file(%s/%s) datasync %d\n", |
54917786 CL |
320 | dentry->d_parent->d_name.name, dentry->d_name.name, |
321 | datasync); | |
1da177e4 | 322 | |
91d5b470 | 323 | nfs_inc_stats(inode, NFSIOS_VFSFSYNC); |
7b159fc1 | 324 | return nfs_do_fsync(ctx, inode); |
1da177e4 LT |
325 | } |
326 | ||
327 | /* | |
4899f9c8 NP |
328 | * This does the "real" work of the write. We must allocate and lock the |
329 | * page to be sent back to the generic routine, which then copies the | |
330 | * data from user space. | |
1da177e4 LT |
331 | * |
332 | * If the writer ends up delaying the write, the writer needs to | |
333 | * increment the page use counts until he is done with the page. | |
334 | */ | |
4899f9c8 NP |
335 | static int nfs_write_begin(struct file *file, struct address_space *mapping, |
336 | loff_t pos, unsigned len, unsigned flags, | |
337 | struct page **pagep, void **fsdata) | |
1da177e4 | 338 | { |
4899f9c8 NP |
339 | int ret; |
340 | pgoff_t index; | |
341 | struct page *page; | |
342 | index = pos >> PAGE_CACHE_SHIFT; | |
343 | ||
b7eaefaa CL |
344 | dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n", |
345 | file->f_path.dentry->d_parent->d_name.name, | |
346 | file->f_path.dentry->d_name.name, | |
347 | mapping->host->i_ino, len, (long long) pos); | |
348 | ||
72cb77f4 TM |
349 | /* |
350 | * Prevent starvation issues if someone is doing a consistency | |
351 | * sync-to-disk | |
352 | */ | |
353 | ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING, | |
354 | nfs_wait_bit_killable, TASK_KILLABLE); | |
355 | if (ret) | |
356 | return ret; | |
357 | ||
54566b2c | 358 | page = grab_cache_page_write_begin(mapping, index, flags); |
4899f9c8 NP |
359 | if (!page) |
360 | return -ENOMEM; | |
361 | *pagep = page; | |
362 | ||
363 | ret = nfs_flush_incompatible(file, page); | |
364 | if (ret) { | |
365 | unlock_page(page); | |
366 | page_cache_release(page); | |
367 | } | |
368 | return ret; | |
1da177e4 LT |
369 | } |
370 | ||
4899f9c8 NP |
371 | static int nfs_write_end(struct file *file, struct address_space *mapping, |
372 | loff_t pos, unsigned len, unsigned copied, | |
373 | struct page *page, void *fsdata) | |
1da177e4 | 374 | { |
4899f9c8 NP |
375 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); |
376 | int status; | |
1da177e4 | 377 | |
b7eaefaa CL |
378 | dfprintk(PAGECACHE, "NFS: write_end(%s/%s(%ld), %u@%lld)\n", |
379 | file->f_path.dentry->d_parent->d_name.name, | |
380 | file->f_path.dentry->d_name.name, | |
381 | mapping->host->i_ino, len, (long long) pos); | |
382 | ||
efc91ed0 TM |
383 | /* |
384 | * Zero any uninitialised parts of the page, and then mark the page | |
385 | * as up to date if it turns out that we're extending the file. | |
386 | */ | |
387 | if (!PageUptodate(page)) { | |
388 | unsigned pglen = nfs_page_length(page); | |
389 | unsigned end = offset + len; | |
390 | ||
391 | if (pglen == 0) { | |
392 | zero_user_segments(page, 0, offset, | |
393 | end, PAGE_CACHE_SIZE); | |
394 | SetPageUptodate(page); | |
395 | } else if (end >= pglen) { | |
396 | zero_user_segment(page, end, PAGE_CACHE_SIZE); | |
397 | if (offset == 0) | |
398 | SetPageUptodate(page); | |
399 | } else | |
400 | zero_user_segment(page, pglen, PAGE_CACHE_SIZE); | |
401 | } | |
402 | ||
4899f9c8 | 403 | status = nfs_updatepage(file, page, offset, copied); |
4899f9c8 NP |
404 | |
405 | unlock_page(page); | |
406 | page_cache_release(page); | |
407 | ||
3d509e54 CL |
408 | if (status < 0) |
409 | return status; | |
410 | return copied; | |
1da177e4 LT |
411 | } |
412 | ||
6b9b3514 DH |
413 | /* |
414 | * Partially or wholly invalidate a page | |
415 | * - Release the private state associated with a page if undergoing complete | |
416 | * page invalidation | |
545db45f | 417 | * - Called if either PG_private or PG_fscache is set on the page |
6b9b3514 DH |
418 | * - Caller holds page lock |
419 | */ | |
2ff28e22 | 420 | static void nfs_invalidate_page(struct page *page, unsigned long offset) |
cd52ed35 | 421 | { |
b7eaefaa CL |
422 | dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset); |
423 | ||
1c75950b TM |
424 | if (offset != 0) |
425 | return; | |
d2ccddf0 | 426 | /* Cancel any unstarted writes on this page */ |
1b3b4a1a | 427 | nfs_wb_page_cancel(page->mapping->host, page); |
545db45f DH |
428 | |
429 | nfs_fscache_invalidate_page(page, page->mapping->host); | |
cd52ed35 TM |
430 | } |
431 | ||
6b9b3514 DH |
432 | /* |
433 | * Attempt to release the private state associated with a page | |
545db45f | 434 | * - Called if either PG_private or PG_fscache is set on the page |
6b9b3514 DH |
435 | * - Caller holds page lock |
436 | * - Return true (may release page) or false (may not) | |
437 | */ | |
cd52ed35 TM |
438 | static int nfs_release_page(struct page *page, gfp_t gfp) |
439 | { | |
b7eaefaa CL |
440 | dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page); |
441 | ||
e3db7691 | 442 | /* If PagePrivate() is set, then the page is not freeable */ |
545db45f DH |
443 | if (PagePrivate(page)) |
444 | return 0; | |
445 | return nfs_fscache_release_page(page, gfp); | |
e3db7691 TM |
446 | } |
447 | ||
6b9b3514 DH |
448 | /* |
449 | * Attempt to clear the private state associated with a page when an error | |
450 | * occurs that requires the cached contents of an inode to be written back or | |
451 | * destroyed | |
545db45f | 452 | * - Called if either PG_private or fscache is set on the page |
6b9b3514 DH |
453 | * - Caller holds page lock |
454 | * - Return 0 if successful, -error otherwise | |
455 | */ | |
e3db7691 TM |
456 | static int nfs_launder_page(struct page *page) |
457 | { | |
b7eaefaa | 458 | struct inode *inode = page->mapping->host; |
545db45f | 459 | struct nfs_inode *nfsi = NFS_I(inode); |
b7eaefaa CL |
460 | |
461 | dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n", | |
462 | inode->i_ino, (long long)page_offset(page)); | |
463 | ||
545db45f | 464 | nfs_fscache_wait_on_page_write(nfsi, page); |
b7eaefaa | 465 | return nfs_wb_page(inode, page); |
cd52ed35 TM |
466 | } |
467 | ||
f5e54d6e | 468 | const struct address_space_operations nfs_file_aops = { |
1da177e4 LT |
469 | .readpage = nfs_readpage, |
470 | .readpages = nfs_readpages, | |
9cccef95 | 471 | .set_page_dirty = __set_page_dirty_nobuffers, |
1da177e4 LT |
472 | .writepage = nfs_writepage, |
473 | .writepages = nfs_writepages, | |
4899f9c8 NP |
474 | .write_begin = nfs_write_begin, |
475 | .write_end = nfs_write_end, | |
cd52ed35 TM |
476 | .invalidatepage = nfs_invalidate_page, |
477 | .releasepage = nfs_release_page, | |
1da177e4 | 478 | .direct_IO = nfs_direct_IO, |
e3db7691 | 479 | .launder_page = nfs_launder_page, |
1da177e4 LT |
480 | }; |
481 | ||
6b9b3514 DH |
482 | /* |
483 | * Notification that a PTE pointing to an NFS page is about to be made | |
484 | * writable, implying that someone is about to modify the page through a | |
485 | * shared-writable mapping | |
486 | */ | |
c2ec175c | 487 | static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
94387fb1 | 488 | { |
c2ec175c | 489 | struct page *page = vmf->page; |
94387fb1 | 490 | struct file *filp = vma->vm_file; |
b7eaefaa | 491 | struct dentry *dentry = filp->f_path.dentry; |
94387fb1 TM |
492 | unsigned pagelen; |
493 | int ret = -EINVAL; | |
4899f9c8 | 494 | struct address_space *mapping; |
94387fb1 | 495 | |
b7eaefaa CL |
496 | dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n", |
497 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
498 | filp->f_mapping->host->i_ino, | |
499 | (long long)page_offset(page)); | |
500 | ||
545db45f DH |
501 | /* make sure the cache has finished storing the page */ |
502 | nfs_fscache_wait_on_page_write(NFS_I(dentry->d_inode), page); | |
503 | ||
94387fb1 | 504 | lock_page(page); |
4899f9c8 | 505 | mapping = page->mapping; |
b7eaefaa | 506 | if (mapping != dentry->d_inode->i_mapping) |
8b1f9ee5 TM |
507 | goto out_unlock; |
508 | ||
509 | ret = 0; | |
94387fb1 | 510 | pagelen = nfs_page_length(page); |
8b1f9ee5 TM |
511 | if (pagelen == 0) |
512 | goto out_unlock; | |
4899f9c8 | 513 | |
8b1f9ee5 TM |
514 | ret = nfs_flush_incompatible(filp, page); |
515 | if (ret != 0) | |
516 | goto out_unlock; | |
517 | ||
518 | ret = nfs_updatepage(filp, page, 0, pagelen); | |
8b1f9ee5 | 519 | out_unlock: |
7fdf5230 TM |
520 | if (!ret) |
521 | return VM_FAULT_LOCKED; | |
8b1f9ee5 | 522 | unlock_page(page); |
7fdf5230 | 523 | return VM_FAULT_SIGBUS; |
94387fb1 TM |
524 | } |
525 | ||
526 | static struct vm_operations_struct nfs_file_vm_ops = { | |
527 | .fault = filemap_fault, | |
528 | .page_mkwrite = nfs_vm_page_mkwrite, | |
529 | }; | |
530 | ||
7b159fc1 TM |
531 | static int nfs_need_sync_write(struct file *filp, struct inode *inode) |
532 | { | |
533 | struct nfs_open_context *ctx; | |
534 | ||
535 | if (IS_SYNC(inode) || (filp->f_flags & O_SYNC)) | |
536 | return 1; | |
cd3758e3 | 537 | ctx = nfs_file_open_context(filp); |
7b159fc1 TM |
538 | if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags)) |
539 | return 1; | |
540 | return 0; | |
541 | } | |
542 | ||
027445c3 BP |
543 | static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov, |
544 | unsigned long nr_segs, loff_t pos) | |
1da177e4 | 545 | { |
01cce933 | 546 | struct dentry * dentry = iocb->ki_filp->f_path.dentry; |
1da177e4 LT |
547 | struct inode * inode = dentry->d_inode; |
548 | ssize_t result; | |
027445c3 | 549 | size_t count = iov_length(iov, nr_segs); |
1da177e4 | 550 | |
1da177e4 | 551 | if (iocb->ki_filp->f_flags & O_DIRECT) |
027445c3 | 552 | return nfs_file_direct_write(iocb, iov, nr_segs, pos); |
1da177e4 | 553 | |
6da24bc9 | 554 | dprintk("NFS: write(%s/%s, %lu@%Ld)\n", |
1da177e4 | 555 | dentry->d_parent->d_name.name, dentry->d_name.name, |
6da24bc9 | 556 | (unsigned long) count, (long long) pos); |
1da177e4 LT |
557 | |
558 | result = -EBUSY; | |
559 | if (IS_SWAPFILE(inode)) | |
560 | goto out_swapfile; | |
7d52e862 TM |
561 | /* |
562 | * O_APPEND implies that we must revalidate the file length. | |
563 | */ | |
564 | if (iocb->ki_filp->f_flags & O_APPEND) { | |
565 | result = nfs_revalidate_file_size(inode, iocb->ki_filp); | |
566 | if (result) | |
567 | goto out; | |
fe51beec | 568 | } |
1da177e4 LT |
569 | |
570 | result = count; | |
571 | if (!count) | |
572 | goto out; | |
573 | ||
91d5b470 | 574 | nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count); |
027445c3 | 575 | result = generic_file_aio_write(iocb, iov, nr_segs, pos); |
200baa21 | 576 | /* Return error values for O_SYNC and IS_SYNC() */ |
7b159fc1 | 577 | if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) { |
cd3758e3 | 578 | int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode); |
200baa21 TM |
579 | if (err < 0) |
580 | result = err; | |
581 | } | |
1da177e4 LT |
582 | out: |
583 | return result; | |
584 | ||
585 | out_swapfile: | |
586 | printk(KERN_INFO "NFS: attempt to write to active swap file!\n"); | |
587 | goto out; | |
588 | } | |
589 | ||
590 | static int do_getlk(struct file *filp, int cmd, struct file_lock *fl) | |
591 | { | |
592 | struct inode *inode = filp->f_mapping->host; | |
593 | int status = 0; | |
594 | ||
595 | lock_kernel(); | |
039c4d7a | 596 | /* Try local locking first */ |
6d34ac19 BF |
597 | posix_test_lock(filp, fl); |
598 | if (fl->fl_type != F_UNLCK) { | |
599 | /* found a conflict */ | |
039c4d7a | 600 | goto out; |
1da177e4 | 601 | } |
039c4d7a TM |
602 | |
603 | if (nfs_have_delegation(inode, FMODE_READ)) | |
604 | goto out_noconflict; | |
605 | ||
606 | if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM) | |
607 | goto out_noconflict; | |
608 | ||
609 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); | |
610 | out: | |
1da177e4 LT |
611 | unlock_kernel(); |
612 | return status; | |
039c4d7a TM |
613 | out_noconflict: |
614 | fl->fl_type = F_UNLCK; | |
615 | goto out; | |
1da177e4 LT |
616 | } |
617 | ||
618 | static int do_vfs_lock(struct file *file, struct file_lock *fl) | |
619 | { | |
620 | int res = 0; | |
621 | switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) { | |
622 | case FL_POSIX: | |
623 | res = posix_lock_file_wait(file, fl); | |
624 | break; | |
625 | case FL_FLOCK: | |
626 | res = flock_lock_file_wait(file, fl); | |
627 | break; | |
628 | default: | |
629 | BUG(); | |
630 | } | |
631 | if (res < 0) | |
46bae1a9 NB |
632 | dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager" |
633 | " - error %d!\n", | |
3110ff80 | 634 | __func__, res); |
1da177e4 LT |
635 | return res; |
636 | } | |
637 | ||
638 | static int do_unlk(struct file *filp, int cmd, struct file_lock *fl) | |
639 | { | |
640 | struct inode *inode = filp->f_mapping->host; | |
1da177e4 LT |
641 | int status; |
642 | ||
1da177e4 LT |
643 | /* |
644 | * Flush all pending writes before doing anything | |
645 | * with locks.. | |
646 | */ | |
29884df0 | 647 | nfs_sync_mapping(filp->f_mapping); |
1da177e4 LT |
648 | |
649 | /* NOTE: special case | |
650 | * If we're signalled while cleaning up locks on process exit, we | |
651 | * still need to complete the unlock. | |
652 | */ | |
653 | lock_kernel(); | |
654 | /* Use local locking if mounted with "-onolock" */ | |
655 | if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) | |
656 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); | |
657 | else | |
658 | status = do_vfs_lock(filp, fl); | |
659 | unlock_kernel(); | |
1da177e4 LT |
660 | return status; |
661 | } | |
662 | ||
663 | static int do_setlk(struct file *filp, int cmd, struct file_lock *fl) | |
664 | { | |
665 | struct inode *inode = filp->f_mapping->host; | |
1da177e4 LT |
666 | int status; |
667 | ||
1da177e4 LT |
668 | /* |
669 | * Flush all pending writes before doing anything | |
670 | * with locks.. | |
671 | */ | |
29884df0 TM |
672 | status = nfs_sync_mapping(filp->f_mapping); |
673 | if (status != 0) | |
1da177e4 LT |
674 | goto out; |
675 | ||
676 | lock_kernel(); | |
677 | /* Use local locking if mounted with "-onolock" */ | |
c4d7c402 | 678 | if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) |
1da177e4 | 679 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); |
c4d7c402 | 680 | else |
1da177e4 LT |
681 | status = do_vfs_lock(filp, fl); |
682 | unlock_kernel(); | |
683 | if (status < 0) | |
684 | goto out; | |
685 | /* | |
686 | * Make sure we clear the cache whenever we try to get the lock. | |
687 | * This makes locking act as a cache coherency point. | |
688 | */ | |
29884df0 | 689 | nfs_sync_mapping(filp->f_mapping); |
b5418383 TM |
690 | if (!nfs_have_delegation(inode, FMODE_READ)) |
691 | nfs_zap_caches(inode); | |
1da177e4 | 692 | out: |
1da177e4 LT |
693 | return status; |
694 | } | |
695 | ||
696 | /* | |
697 | * Lock a (portion of) a file | |
698 | */ | |
699 | static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl) | |
700 | { | |
6da24bc9 | 701 | struct inode *inode = filp->f_mapping->host; |
2116271a | 702 | int ret = -ENOLCK; |
1da177e4 | 703 | |
6da24bc9 CL |
704 | dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n", |
705 | filp->f_path.dentry->d_parent->d_name.name, | |
706 | filp->f_path.dentry->d_name.name, | |
1da177e4 LT |
707 | fl->fl_type, fl->fl_flags, |
708 | (long long)fl->fl_start, (long long)fl->fl_end); | |
6da24bc9 | 709 | |
91d5b470 | 710 | nfs_inc_stats(inode, NFSIOS_VFSLOCK); |
1da177e4 LT |
711 | |
712 | /* No mandatory locks over NFS */ | |
dfad9441 | 713 | if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK) |
2116271a TM |
714 | goto out_err; |
715 | ||
716 | if (NFS_PROTO(inode)->lock_check_bounds != NULL) { | |
717 | ret = NFS_PROTO(inode)->lock_check_bounds(fl); | |
718 | if (ret < 0) | |
719 | goto out_err; | |
720 | } | |
1da177e4 LT |
721 | |
722 | if (IS_GETLK(cmd)) | |
2116271a TM |
723 | ret = do_getlk(filp, cmd, fl); |
724 | else if (fl->fl_type == F_UNLCK) | |
725 | ret = do_unlk(filp, cmd, fl); | |
726 | else | |
727 | ret = do_setlk(filp, cmd, fl); | |
728 | out_err: | |
729 | return ret; | |
1da177e4 LT |
730 | } |
731 | ||
732 | /* | |
733 | * Lock a (portion of) a file | |
734 | */ | |
735 | static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl) | |
736 | { | |
6da24bc9 CL |
737 | dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n", |
738 | filp->f_path.dentry->d_parent->d_name.name, | |
739 | filp->f_path.dentry->d_name.name, | |
1da177e4 LT |
740 | fl->fl_type, fl->fl_flags); |
741 | ||
1da177e4 LT |
742 | if (!(fl->fl_flags & FL_FLOCK)) |
743 | return -ENOLCK; | |
744 | ||
745 | /* We're simulating flock() locks using posix locks on the server */ | |
746 | fl->fl_owner = (fl_owner_t)filp; | |
747 | fl->fl_start = 0; | |
748 | fl->fl_end = OFFSET_MAX; | |
749 | ||
750 | if (fl->fl_type == F_UNLCK) | |
751 | return do_unlk(filp, cmd, fl); | |
752 | return do_setlk(filp, cmd, fl); | |
753 | } | |
370f6599 | 754 | |
6da24bc9 CL |
755 | /* |
756 | * There is no protocol support for leases, so we have no way to implement | |
757 | * them correctly in the face of opens by other clients. | |
758 | */ | |
370f6599 BF |
759 | static int nfs_setlease(struct file *file, long arg, struct file_lock **fl) |
760 | { | |
6da24bc9 CL |
761 | dprintk("NFS: setlease(%s/%s, arg=%ld)\n", |
762 | file->f_path.dentry->d_parent->d_name.name, | |
763 | file->f_path.dentry->d_name.name, arg); | |
764 | ||
370f6599 BF |
765 | return -EINVAL; |
766 | } |