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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> | |
1da177e4 | 27 | #include <linux/pagemap.h> |
e8edc6e0 | 28 | #include <linux/aio.h> |
5a0e3ad6 | 29 | #include <linux/gfp.h> |
b608b283 | 30 | #include <linux/swap.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" |
e5e94017 | 39 | #include "pnfs.h" |
1da177e4 LT |
40 | |
41 | #define NFSDBG_FACILITY NFSDBG_FILE | |
42 | ||
43 | static int nfs_file_open(struct inode *, struct file *); | |
44 | static int nfs_file_release(struct inode *, struct file *); | |
980802e3 | 45 | static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin); |
1da177e4 | 46 | static int nfs_file_mmap(struct file *, struct vm_area_struct *); |
f0930fff JA |
47 | static ssize_t nfs_file_splice_read(struct file *filp, loff_t *ppos, |
48 | struct pipe_inode_info *pipe, | |
49 | size_t count, unsigned int flags); | |
027445c3 BP |
50 | static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov, |
51 | unsigned long nr_segs, loff_t pos); | |
bf40d343 SJ |
52 | static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe, |
53 | struct file *filp, loff_t *ppos, | |
54 | size_t count, unsigned int flags); | |
027445c3 BP |
55 | static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov, |
56 | unsigned long nr_segs, loff_t pos); | |
75e1fcc0 | 57 | static int nfs_file_flush(struct file *, fl_owner_t id); |
7ea80859 | 58 | static int nfs_file_fsync(struct file *, int datasync); |
1da177e4 LT |
59 | static int nfs_check_flags(int flags); |
60 | static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl); | |
61 | static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl); | |
370f6599 | 62 | static int nfs_setlease(struct file *file, long arg, struct file_lock **fl); |
1da177e4 | 63 | |
f0f37e2f | 64 | static const struct vm_operations_struct nfs_file_vm_ops; |
94387fb1 | 65 | |
4b6f5d20 | 66 | const struct file_operations nfs_file_operations = { |
980802e3 | 67 | .llseek = nfs_file_llseek, |
1da177e4 LT |
68 | .read = do_sync_read, |
69 | .write = do_sync_write, | |
027445c3 BP |
70 | .aio_read = nfs_file_read, |
71 | .aio_write = nfs_file_write, | |
1da177e4 LT |
72 | .mmap = nfs_file_mmap, |
73 | .open = nfs_file_open, | |
74 | .flush = nfs_file_flush, | |
75 | .release = nfs_file_release, | |
54917786 | 76 | .fsync = nfs_file_fsync, |
1da177e4 LT |
77 | .lock = nfs_lock, |
78 | .flock = nfs_flock, | |
f0930fff | 79 | .splice_read = nfs_file_splice_read, |
bf40d343 | 80 | .splice_write = nfs_file_splice_write, |
1da177e4 | 81 | .check_flags = nfs_check_flags, |
370f6599 | 82 | .setlease = nfs_setlease, |
1da177e4 LT |
83 | }; |
84 | ||
92e1d5be | 85 | const struct inode_operations nfs_file_inode_operations = { |
1da177e4 LT |
86 | .permission = nfs_permission, |
87 | .getattr = nfs_getattr, | |
88 | .setattr = nfs_setattr, | |
89 | }; | |
90 | ||
b7fa0554 | 91 | #ifdef CONFIG_NFS_V3 |
92e1d5be | 92 | const struct inode_operations nfs3_file_inode_operations = { |
b7fa0554 AG |
93 | .permission = nfs_permission, |
94 | .getattr = nfs_getattr, | |
95 | .setattr = nfs_setattr, | |
96 | .listxattr = nfs3_listxattr, | |
97 | .getxattr = nfs3_getxattr, | |
98 | .setxattr = nfs3_setxattr, | |
99 | .removexattr = nfs3_removexattr, | |
100 | }; | |
101 | #endif /* CONFIG_NFS_v3 */ | |
102 | ||
1da177e4 LT |
103 | /* Hack for future NFS swap support */ |
104 | #ifndef IS_SWAPFILE | |
105 | # define IS_SWAPFILE(inode) (0) | |
106 | #endif | |
107 | ||
108 | static int nfs_check_flags(int flags) | |
109 | { | |
110 | if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT)) | |
111 | return -EINVAL; | |
112 | ||
113 | return 0; | |
114 | } | |
115 | ||
116 | /* | |
117 | * Open file | |
118 | */ | |
119 | static int | |
120 | nfs_file_open(struct inode *inode, struct file *filp) | |
121 | { | |
1da177e4 LT |
122 | int res; |
123 | ||
6da24bc9 | 124 | dprintk("NFS: open file(%s/%s)\n", |
cc0dd2d1 CL |
125 | filp->f_path.dentry->d_parent->d_name.name, |
126 | filp->f_path.dentry->d_name.name); | |
127 | ||
c2459dc4 | 128 | nfs_inc_stats(inode, NFSIOS_VFSOPEN); |
1da177e4 LT |
129 | res = nfs_check_flags(filp->f_flags); |
130 | if (res) | |
131 | return res; | |
132 | ||
46cb650c | 133 | res = nfs_open(inode, filp); |
1da177e4 LT |
134 | return res; |
135 | } | |
136 | ||
137 | static int | |
138 | nfs_file_release(struct inode *inode, struct file *filp) | |
139 | { | |
6da24bc9 CL |
140 | struct dentry *dentry = filp->f_path.dentry; |
141 | ||
142 | dprintk("NFS: release(%s/%s)\n", | |
143 | dentry->d_parent->d_name.name, | |
144 | dentry->d_name.name); | |
145 | ||
91d5b470 | 146 | nfs_inc_stats(inode, NFSIOS_VFSRELEASE); |
46cb650c | 147 | return nfs_release(inode, filp); |
1da177e4 LT |
148 | } |
149 | ||
980802e3 TM |
150 | /** |
151 | * nfs_revalidate_size - Revalidate the file size | |
152 | * @inode - pointer to inode struct | |
153 | * @file - pointer to struct file | |
154 | * | |
155 | * Revalidates the file length. This is basically a wrapper around | |
156 | * nfs_revalidate_inode() that takes into account the fact that we may | |
157 | * have cached writes (in which case we don't care about the server's | |
158 | * idea of what the file length is), or O_DIRECT (in which case we | |
159 | * shouldn't trust the cache). | |
160 | */ | |
161 | static int nfs_revalidate_file_size(struct inode *inode, struct file *filp) | |
162 | { | |
163 | struct nfs_server *server = NFS_SERVER(inode); | |
164 | struct nfs_inode *nfsi = NFS_I(inode); | |
165 | ||
d7cf8dd0 TM |
166 | if (nfs_have_delegated_attributes(inode)) |
167 | goto out_noreval; | |
168 | ||
980802e3 TM |
169 | if (filp->f_flags & O_DIRECT) |
170 | goto force_reval; | |
d7cf8dd0 TM |
171 | if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) |
172 | goto force_reval; | |
173 | if (nfs_attribute_timeout(inode)) | |
174 | goto force_reval; | |
175 | out_noreval: | |
176 | return 0; | |
980802e3 TM |
177 | force_reval: |
178 | return __nfs_revalidate_inode(server, inode); | |
179 | } | |
180 | ||
181 | static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin) | |
182 | { | |
9465efc9 | 183 | loff_t loff; |
e89e896d | 184 | |
6da24bc9 | 185 | dprintk("NFS: llseek file(%s/%s, %lld, %d)\n", |
b84e06c5 CL |
186 | filp->f_path.dentry->d_parent->d_name.name, |
187 | filp->f_path.dentry->d_name.name, | |
188 | offset, origin); | |
189 | ||
06222e49 JB |
190 | /* |
191 | * origin == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate | |
192 | * the cached file length | |
193 | */ | |
194 | if (origin != SEEK_SET || origin != SEEK_CUR) { | |
980802e3 | 195 | struct inode *inode = filp->f_mapping->host; |
d5e66348 | 196 | |
980802e3 TM |
197 | int retval = nfs_revalidate_file_size(inode, filp); |
198 | if (retval < 0) | |
199 | return (loff_t)retval; | |
d5e66348 TM |
200 | |
201 | spin_lock(&inode->i_lock); | |
202 | loff = generic_file_llseek_unlocked(filp, offset, origin); | |
203 | spin_unlock(&inode->i_lock); | |
204 | } else | |
205 | loff = generic_file_llseek_unlocked(filp, offset, origin); | |
9465efc9 | 206 | return loff; |
980802e3 TM |
207 | } |
208 | ||
1da177e4 LT |
209 | /* |
210 | * Flush all dirty pages, and check for write errors. | |
1da177e4 LT |
211 | */ |
212 | static int | |
75e1fcc0 | 213 | nfs_file_flush(struct file *file, fl_owner_t id) |
1da177e4 | 214 | { |
6da24bc9 CL |
215 | struct dentry *dentry = file->f_path.dentry; |
216 | struct inode *inode = dentry->d_inode; | |
1da177e4 | 217 | |
6da24bc9 CL |
218 | dprintk("NFS: flush(%s/%s)\n", |
219 | dentry->d_parent->d_name.name, | |
220 | dentry->d_name.name); | |
1da177e4 | 221 | |
c2459dc4 | 222 | nfs_inc_stats(inode, NFSIOS_VFSFLUSH); |
1da177e4 LT |
223 | if ((file->f_mode & FMODE_WRITE) == 0) |
224 | return 0; | |
7b159fc1 | 225 | |
7fe5c398 | 226 | /* Flush writes to the server and return any errors */ |
af7fa165 | 227 | return vfs_fsync(file, 0); |
1da177e4 LT |
228 | } |
229 | ||
230 | static ssize_t | |
027445c3 BP |
231 | nfs_file_read(struct kiocb *iocb, const struct iovec *iov, |
232 | unsigned long nr_segs, loff_t pos) | |
1da177e4 | 233 | { |
01cce933 | 234 | struct dentry * dentry = iocb->ki_filp->f_path.dentry; |
1da177e4 LT |
235 | struct inode * inode = dentry->d_inode; |
236 | ssize_t result; | |
027445c3 | 237 | size_t count = iov_length(iov, nr_segs); |
1da177e4 | 238 | |
1da177e4 | 239 | if (iocb->ki_filp->f_flags & O_DIRECT) |
027445c3 | 240 | return nfs_file_direct_read(iocb, iov, nr_segs, pos); |
1da177e4 | 241 | |
6da24bc9 | 242 | dprintk("NFS: read(%s/%s, %lu@%lu)\n", |
1da177e4 LT |
243 | dentry->d_parent->d_name.name, dentry->d_name.name, |
244 | (unsigned long) count, (unsigned long) pos); | |
245 | ||
44b11874 | 246 | result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping); |
4184dcf2 | 247 | if (!result) { |
027445c3 | 248 | result = generic_file_aio_read(iocb, iov, nr_segs, pos); |
4184dcf2 CL |
249 | if (result > 0) |
250 | nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result); | |
251 | } | |
1da177e4 LT |
252 | return result; |
253 | } | |
254 | ||
255 | static ssize_t | |
f0930fff JA |
256 | nfs_file_splice_read(struct file *filp, loff_t *ppos, |
257 | struct pipe_inode_info *pipe, size_t count, | |
258 | unsigned int flags) | |
1da177e4 | 259 | { |
01cce933 | 260 | struct dentry *dentry = filp->f_path.dentry; |
1da177e4 LT |
261 | struct inode *inode = dentry->d_inode; |
262 | ssize_t res; | |
263 | ||
6da24bc9 | 264 | dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n", |
1da177e4 LT |
265 | dentry->d_parent->d_name.name, dentry->d_name.name, |
266 | (unsigned long) count, (unsigned long long) *ppos); | |
267 | ||
44b11874 | 268 | res = nfs_revalidate_mapping(inode, filp->f_mapping); |
aa2f1ef1 | 269 | if (!res) { |
f0930fff | 270 | res = generic_file_splice_read(filp, ppos, pipe, count, flags); |
aa2f1ef1 CL |
271 | if (res > 0) |
272 | nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, res); | |
273 | } | |
1da177e4 LT |
274 | return res; |
275 | } | |
276 | ||
277 | static int | |
278 | nfs_file_mmap(struct file * file, struct vm_area_struct * vma) | |
279 | { | |
01cce933 | 280 | struct dentry *dentry = file->f_path.dentry; |
1da177e4 LT |
281 | struct inode *inode = dentry->d_inode; |
282 | int status; | |
283 | ||
6da24bc9 | 284 | dprintk("NFS: mmap(%s/%s)\n", |
1da177e4 LT |
285 | dentry->d_parent->d_name.name, dentry->d_name.name); |
286 | ||
e1ebfd33 TM |
287 | /* Note: generic_file_mmap() returns ENOSYS on nommu systems |
288 | * so we call that before revalidating the mapping | |
289 | */ | |
290 | status = generic_file_mmap(file, vma); | |
94387fb1 TM |
291 | if (!status) { |
292 | vma->vm_ops = &nfs_file_vm_ops; | |
e1ebfd33 | 293 | status = nfs_revalidate_mapping(inode, file->f_mapping); |
94387fb1 | 294 | } |
1da177e4 LT |
295 | return status; |
296 | } | |
297 | ||
298 | /* | |
299 | * Flush any dirty pages for this process, and check for write errors. | |
300 | * The return status from this call provides a reliable indication of | |
301 | * whether any write errors occurred for this process. | |
af7fa165 TM |
302 | * |
303 | * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to | |
304 | * disk, but it retrieves and clears ctx->error after synching, despite | |
305 | * the two being set at the same time in nfs_context_set_write_error(). | |
306 | * This is because the former is used to notify the _next_ call to | |
25985edc | 307 | * nfs_file_write() that a write error occurred, and hence cause it to |
af7fa165 | 308 | * fall back to doing a synchronous write. |
1da177e4 LT |
309 | */ |
310 | static int | |
7ea80859 | 311 | nfs_file_fsync(struct file *file, int datasync) |
1da177e4 | 312 | { |
7ea80859 | 313 | struct dentry *dentry = file->f_path.dentry; |
cd3758e3 | 314 | struct nfs_open_context *ctx = nfs_file_open_context(file); |
1da177e4 | 315 | struct inode *inode = dentry->d_inode; |
af7fa165 TM |
316 | int have_error, status; |
317 | int ret = 0; | |
318 | ||
1da177e4 | 319 | |
6da24bc9 | 320 | dprintk("NFS: fsync file(%s/%s) datasync %d\n", |
54917786 CL |
321 | dentry->d_parent->d_name.name, dentry->d_name.name, |
322 | datasync); | |
1da177e4 | 323 | |
91d5b470 | 324 | nfs_inc_stats(inode, NFSIOS_VFSFSYNC); |
af7fa165 TM |
325 | have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); |
326 | status = nfs_commit_inode(inode, FLUSH_SYNC); | |
327 | have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); | |
328 | if (have_error) | |
329 | ret = xchg(&ctx->error, 0); | |
0702099b | 330 | if (!ret && status < 0) |
af7fa165 | 331 | ret = status; |
863a3c6c AA |
332 | if (!ret && !datasync) |
333 | /* application has asked for meta-data sync */ | |
ef311537 | 334 | ret = pnfs_layoutcommit_inode(inode, true); |
af7fa165 | 335 | return ret; |
1da177e4 LT |
336 | } |
337 | ||
38c73044 PS |
338 | /* |
339 | * Decide whether a read/modify/write cycle may be more efficient | |
340 | * then a modify/write/read cycle when writing to a page in the | |
341 | * page cache. | |
342 | * | |
343 | * The modify/write/read cycle may occur if a page is read before | |
344 | * being completely filled by the writer. In this situation, the | |
345 | * page must be completely written to stable storage on the server | |
346 | * before it can be refilled by reading in the page from the server. | |
347 | * This can lead to expensive, small, FILE_SYNC mode writes being | |
348 | * done. | |
349 | * | |
350 | * It may be more efficient to read the page first if the file is | |
351 | * open for reading in addition to writing, the page is not marked | |
352 | * as Uptodate, it is not dirty or waiting to be committed, | |
353 | * indicating that it was previously allocated and then modified, | |
354 | * that there were valid bytes of data in that range of the file, | |
355 | * and that the new data won't completely replace the old data in | |
356 | * that range of the file. | |
357 | */ | |
358 | static int nfs_want_read_modify_write(struct file *file, struct page *page, | |
359 | loff_t pos, unsigned len) | |
360 | { | |
361 | unsigned int pglen = nfs_page_length(page); | |
362 | unsigned int offset = pos & (PAGE_CACHE_SIZE - 1); | |
363 | unsigned int end = offset + len; | |
364 | ||
365 | if ((file->f_mode & FMODE_READ) && /* open for read? */ | |
366 | !PageUptodate(page) && /* Uptodate? */ | |
367 | !PagePrivate(page) && /* i/o request already? */ | |
368 | pglen && /* valid bytes of file? */ | |
369 | (end < pglen || offset)) /* replace all valid bytes? */ | |
370 | return 1; | |
371 | return 0; | |
372 | } | |
373 | ||
1da177e4 | 374 | /* |
4899f9c8 NP |
375 | * This does the "real" work of the write. We must allocate and lock the |
376 | * page to be sent back to the generic routine, which then copies the | |
377 | * data from user space. | |
1da177e4 LT |
378 | * |
379 | * If the writer ends up delaying the write, the writer needs to | |
380 | * increment the page use counts until he is done with the page. | |
381 | */ | |
4899f9c8 NP |
382 | static int nfs_write_begin(struct file *file, struct address_space *mapping, |
383 | loff_t pos, unsigned len, unsigned flags, | |
384 | struct page **pagep, void **fsdata) | |
1da177e4 | 385 | { |
4899f9c8 | 386 | int ret; |
38c73044 | 387 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
4899f9c8 | 388 | struct page *page; |
38c73044 | 389 | int once_thru = 0; |
4899f9c8 | 390 | |
b7eaefaa CL |
391 | dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n", |
392 | file->f_path.dentry->d_parent->d_name.name, | |
393 | file->f_path.dentry->d_name.name, | |
394 | mapping->host->i_ino, len, (long long) pos); | |
395 | ||
38c73044 | 396 | start: |
72cb77f4 TM |
397 | /* |
398 | * Prevent starvation issues if someone is doing a consistency | |
399 | * sync-to-disk | |
400 | */ | |
401 | ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING, | |
402 | nfs_wait_bit_killable, TASK_KILLABLE); | |
403 | if (ret) | |
404 | return ret; | |
405 | ||
54566b2c | 406 | page = grab_cache_page_write_begin(mapping, index, flags); |
4899f9c8 NP |
407 | if (!page) |
408 | return -ENOMEM; | |
409 | *pagep = page; | |
410 | ||
411 | ret = nfs_flush_incompatible(file, page); | |
412 | if (ret) { | |
413 | unlock_page(page); | |
414 | page_cache_release(page); | |
38c73044 PS |
415 | } else if (!once_thru && |
416 | nfs_want_read_modify_write(file, page, pos, len)) { | |
417 | once_thru = 1; | |
418 | ret = nfs_readpage(file, page); | |
419 | page_cache_release(page); | |
420 | if (!ret) | |
421 | goto start; | |
4899f9c8 NP |
422 | } |
423 | return ret; | |
1da177e4 LT |
424 | } |
425 | ||
4899f9c8 NP |
426 | static int nfs_write_end(struct file *file, struct address_space *mapping, |
427 | loff_t pos, unsigned len, unsigned copied, | |
428 | struct page *page, void *fsdata) | |
1da177e4 | 429 | { |
4899f9c8 NP |
430 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); |
431 | int status; | |
1da177e4 | 432 | |
b7eaefaa CL |
433 | dfprintk(PAGECACHE, "NFS: write_end(%s/%s(%ld), %u@%lld)\n", |
434 | file->f_path.dentry->d_parent->d_name.name, | |
435 | file->f_path.dentry->d_name.name, | |
436 | mapping->host->i_ino, len, (long long) pos); | |
437 | ||
efc91ed0 TM |
438 | /* |
439 | * Zero any uninitialised parts of the page, and then mark the page | |
440 | * as up to date if it turns out that we're extending the file. | |
441 | */ | |
442 | if (!PageUptodate(page)) { | |
443 | unsigned pglen = nfs_page_length(page); | |
444 | unsigned end = offset + len; | |
445 | ||
446 | if (pglen == 0) { | |
447 | zero_user_segments(page, 0, offset, | |
448 | end, PAGE_CACHE_SIZE); | |
449 | SetPageUptodate(page); | |
450 | } else if (end >= pglen) { | |
451 | zero_user_segment(page, end, PAGE_CACHE_SIZE); | |
452 | if (offset == 0) | |
453 | SetPageUptodate(page); | |
454 | } else | |
455 | zero_user_segment(page, pglen, PAGE_CACHE_SIZE); | |
456 | } | |
457 | ||
4899f9c8 | 458 | status = nfs_updatepage(file, page, offset, copied); |
4899f9c8 NP |
459 | |
460 | unlock_page(page); | |
461 | page_cache_release(page); | |
462 | ||
3d509e54 CL |
463 | if (status < 0) |
464 | return status; | |
465 | return copied; | |
1da177e4 LT |
466 | } |
467 | ||
6b9b3514 DH |
468 | /* |
469 | * Partially or wholly invalidate a page | |
470 | * - Release the private state associated with a page if undergoing complete | |
471 | * page invalidation | |
545db45f | 472 | * - Called if either PG_private or PG_fscache is set on the page |
6b9b3514 DH |
473 | * - Caller holds page lock |
474 | */ | |
2ff28e22 | 475 | static void nfs_invalidate_page(struct page *page, unsigned long offset) |
cd52ed35 | 476 | { |
b7eaefaa CL |
477 | dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset); |
478 | ||
1c75950b TM |
479 | if (offset != 0) |
480 | return; | |
d2ccddf0 | 481 | /* Cancel any unstarted writes on this page */ |
1b3b4a1a | 482 | nfs_wb_page_cancel(page->mapping->host, page); |
545db45f DH |
483 | |
484 | nfs_fscache_invalidate_page(page, page->mapping->host); | |
cd52ed35 TM |
485 | } |
486 | ||
6b9b3514 DH |
487 | /* |
488 | * Attempt to release the private state associated with a page | |
545db45f | 489 | * - Called if either PG_private or PG_fscache is set on the page |
6b9b3514 DH |
490 | * - Caller holds page lock |
491 | * - Return true (may release page) or false (may not) | |
492 | */ | |
cd52ed35 TM |
493 | static int nfs_release_page(struct page *page, gfp_t gfp) |
494 | { | |
b608b283 TM |
495 | struct address_space *mapping = page->mapping; |
496 | ||
b7eaefaa CL |
497 | dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page); |
498 | ||
d812e575 | 499 | /* Only do I/O if gfp is a superset of GFP_KERNEL */ |
b608b283 TM |
500 | if (mapping && (gfp & GFP_KERNEL) == GFP_KERNEL) { |
501 | int how = FLUSH_SYNC; | |
502 | ||
503 | /* Don't let kswapd deadlock waiting for OOM RPC calls */ | |
504 | if (current_is_kswapd()) | |
505 | how = 0; | |
506 | nfs_commit_inode(mapping->host, how); | |
507 | } | |
e3db7691 | 508 | /* If PagePrivate() is set, then the page is not freeable */ |
545db45f DH |
509 | if (PagePrivate(page)) |
510 | return 0; | |
511 | return nfs_fscache_release_page(page, gfp); | |
e3db7691 TM |
512 | } |
513 | ||
6b9b3514 DH |
514 | /* |
515 | * Attempt to clear the private state associated with a page when an error | |
516 | * occurs that requires the cached contents of an inode to be written back or | |
517 | * destroyed | |
545db45f | 518 | * - Called if either PG_private or fscache is set on the page |
6b9b3514 DH |
519 | * - Caller holds page lock |
520 | * - Return 0 if successful, -error otherwise | |
521 | */ | |
e3db7691 TM |
522 | static int nfs_launder_page(struct page *page) |
523 | { | |
b7eaefaa | 524 | struct inode *inode = page->mapping->host; |
545db45f | 525 | struct nfs_inode *nfsi = NFS_I(inode); |
b7eaefaa CL |
526 | |
527 | dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n", | |
528 | inode->i_ino, (long long)page_offset(page)); | |
529 | ||
545db45f | 530 | nfs_fscache_wait_on_page_write(nfsi, page); |
b7eaefaa | 531 | return nfs_wb_page(inode, page); |
cd52ed35 TM |
532 | } |
533 | ||
f5e54d6e | 534 | const struct address_space_operations nfs_file_aops = { |
1da177e4 LT |
535 | .readpage = nfs_readpage, |
536 | .readpages = nfs_readpages, | |
9cccef95 | 537 | .set_page_dirty = __set_page_dirty_nobuffers, |
1da177e4 LT |
538 | .writepage = nfs_writepage, |
539 | .writepages = nfs_writepages, | |
4899f9c8 NP |
540 | .write_begin = nfs_write_begin, |
541 | .write_end = nfs_write_end, | |
cd52ed35 TM |
542 | .invalidatepage = nfs_invalidate_page, |
543 | .releasepage = nfs_release_page, | |
1da177e4 | 544 | .direct_IO = nfs_direct_IO, |
074cc1de | 545 | .migratepage = nfs_migrate_page, |
e3db7691 | 546 | .launder_page = nfs_launder_page, |
f590f333 | 547 | .error_remove_page = generic_error_remove_page, |
1da177e4 LT |
548 | }; |
549 | ||
6b9b3514 DH |
550 | /* |
551 | * Notification that a PTE pointing to an NFS page is about to be made | |
552 | * writable, implying that someone is about to modify the page through a | |
553 | * shared-writable mapping | |
554 | */ | |
c2ec175c | 555 | static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
94387fb1 | 556 | { |
c2ec175c | 557 | struct page *page = vmf->page; |
94387fb1 | 558 | struct file *filp = vma->vm_file; |
b7eaefaa | 559 | struct dentry *dentry = filp->f_path.dentry; |
94387fb1 | 560 | unsigned pagelen; |
bc4866b6 | 561 | int ret = VM_FAULT_NOPAGE; |
4899f9c8 | 562 | struct address_space *mapping; |
94387fb1 | 563 | |
b7eaefaa CL |
564 | dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n", |
565 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
566 | filp->f_mapping->host->i_ino, | |
567 | (long long)page_offset(page)); | |
568 | ||
545db45f DH |
569 | /* make sure the cache has finished storing the page */ |
570 | nfs_fscache_wait_on_page_write(NFS_I(dentry->d_inode), page); | |
571 | ||
94387fb1 | 572 | lock_page(page); |
4899f9c8 | 573 | mapping = page->mapping; |
b7eaefaa | 574 | if (mapping != dentry->d_inode->i_mapping) |
8b1f9ee5 TM |
575 | goto out_unlock; |
576 | ||
94387fb1 | 577 | pagelen = nfs_page_length(page); |
8b1f9ee5 TM |
578 | if (pagelen == 0) |
579 | goto out_unlock; | |
4899f9c8 | 580 | |
bc4866b6 TM |
581 | ret = VM_FAULT_LOCKED; |
582 | if (nfs_flush_incompatible(filp, page) == 0 && | |
583 | nfs_updatepage(filp, page, 0, pagelen) == 0) | |
584 | goto out; | |
8b1f9ee5 | 585 | |
bc4866b6 | 586 | ret = VM_FAULT_SIGBUS; |
8b1f9ee5 TM |
587 | out_unlock: |
588 | unlock_page(page); | |
bc4866b6 TM |
589 | out: |
590 | return ret; | |
94387fb1 TM |
591 | } |
592 | ||
f0f37e2f | 593 | static const struct vm_operations_struct nfs_file_vm_ops = { |
94387fb1 TM |
594 | .fault = filemap_fault, |
595 | .page_mkwrite = nfs_vm_page_mkwrite, | |
596 | }; | |
597 | ||
7b159fc1 TM |
598 | static int nfs_need_sync_write(struct file *filp, struct inode *inode) |
599 | { | |
600 | struct nfs_open_context *ctx; | |
601 | ||
6b2f3d1f | 602 | if (IS_SYNC(inode) || (filp->f_flags & O_DSYNC)) |
7b159fc1 | 603 | return 1; |
cd3758e3 | 604 | ctx = nfs_file_open_context(filp); |
7b159fc1 TM |
605 | if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags)) |
606 | return 1; | |
607 | return 0; | |
608 | } | |
609 | ||
027445c3 BP |
610 | static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov, |
611 | unsigned long nr_segs, loff_t pos) | |
1da177e4 | 612 | { |
01cce933 | 613 | struct dentry * dentry = iocb->ki_filp->f_path.dentry; |
1da177e4 | 614 | struct inode * inode = dentry->d_inode; |
7e381172 | 615 | unsigned long written = 0; |
1da177e4 | 616 | ssize_t result; |
027445c3 | 617 | size_t count = iov_length(iov, nr_segs); |
1da177e4 | 618 | |
1da177e4 | 619 | if (iocb->ki_filp->f_flags & O_DIRECT) |
027445c3 | 620 | return nfs_file_direct_write(iocb, iov, nr_segs, pos); |
1da177e4 | 621 | |
6da24bc9 | 622 | dprintk("NFS: write(%s/%s, %lu@%Ld)\n", |
1da177e4 | 623 | dentry->d_parent->d_name.name, dentry->d_name.name, |
6da24bc9 | 624 | (unsigned long) count, (long long) pos); |
1da177e4 LT |
625 | |
626 | result = -EBUSY; | |
627 | if (IS_SWAPFILE(inode)) | |
628 | goto out_swapfile; | |
7d52e862 TM |
629 | /* |
630 | * O_APPEND implies that we must revalidate the file length. | |
631 | */ | |
632 | if (iocb->ki_filp->f_flags & O_APPEND) { | |
633 | result = nfs_revalidate_file_size(inode, iocb->ki_filp); | |
634 | if (result) | |
635 | goto out; | |
fe51beec | 636 | } |
1da177e4 LT |
637 | |
638 | result = count; | |
639 | if (!count) | |
640 | goto out; | |
641 | ||
027445c3 | 642 | result = generic_file_aio_write(iocb, iov, nr_segs, pos); |
7e381172 CL |
643 | if (result > 0) |
644 | written = result; | |
645 | ||
6b2f3d1f | 646 | /* Return error values for O_DSYNC and IS_SYNC() */ |
7b159fc1 | 647 | if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) { |
af7fa165 | 648 | int err = vfs_fsync(iocb->ki_filp, 0); |
200baa21 TM |
649 | if (err < 0) |
650 | result = err; | |
651 | } | |
7e381172 CL |
652 | if (result > 0) |
653 | nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written); | |
1da177e4 LT |
654 | out: |
655 | return result; | |
656 | ||
657 | out_swapfile: | |
658 | printk(KERN_INFO "NFS: attempt to write to active swap file!\n"); | |
659 | goto out; | |
660 | } | |
661 | ||
bf40d343 SJ |
662 | static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe, |
663 | struct file *filp, loff_t *ppos, | |
664 | size_t count, unsigned int flags) | |
665 | { | |
666 | struct dentry *dentry = filp->f_path.dentry; | |
667 | struct inode *inode = dentry->d_inode; | |
7e381172 | 668 | unsigned long written = 0; |
bf40d343 SJ |
669 | ssize_t ret; |
670 | ||
671 | dprintk("NFS splice_write(%s/%s, %lu@%llu)\n", | |
672 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
673 | (unsigned long) count, (unsigned long long) *ppos); | |
674 | ||
675 | /* | |
676 | * The combination of splice and an O_APPEND destination is disallowed. | |
677 | */ | |
678 | ||
bf40d343 | 679 | ret = generic_file_splice_write(pipe, filp, ppos, count, flags); |
7e381172 CL |
680 | if (ret > 0) |
681 | written = ret; | |
682 | ||
bf40d343 | 683 | if (ret >= 0 && nfs_need_sync_write(filp, inode)) { |
af7fa165 | 684 | int err = vfs_fsync(filp, 0); |
bf40d343 SJ |
685 | if (err < 0) |
686 | ret = err; | |
687 | } | |
7e381172 CL |
688 | if (ret > 0) |
689 | nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written); | |
bf40d343 SJ |
690 | return ret; |
691 | } | |
692 | ||
5eebde23 SJ |
693 | static int |
694 | do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local) | |
1da177e4 LT |
695 | { |
696 | struct inode *inode = filp->f_mapping->host; | |
697 | int status = 0; | |
21ac19d4 | 698 | unsigned int saved_type = fl->fl_type; |
1da177e4 | 699 | |
039c4d7a | 700 | /* Try local locking first */ |
6d34ac19 BF |
701 | posix_test_lock(filp, fl); |
702 | if (fl->fl_type != F_UNLCK) { | |
703 | /* found a conflict */ | |
039c4d7a | 704 | goto out; |
1da177e4 | 705 | } |
21ac19d4 | 706 | fl->fl_type = saved_type; |
039c4d7a TM |
707 | |
708 | if (nfs_have_delegation(inode, FMODE_READ)) | |
709 | goto out_noconflict; | |
710 | ||
5eebde23 | 711 | if (is_local) |
039c4d7a TM |
712 | goto out_noconflict; |
713 | ||
714 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); | |
715 | out: | |
1da177e4 | 716 | return status; |
039c4d7a TM |
717 | out_noconflict: |
718 | fl->fl_type = F_UNLCK; | |
719 | goto out; | |
1da177e4 LT |
720 | } |
721 | ||
722 | static int do_vfs_lock(struct file *file, struct file_lock *fl) | |
723 | { | |
724 | int res = 0; | |
725 | switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) { | |
726 | case FL_POSIX: | |
727 | res = posix_lock_file_wait(file, fl); | |
728 | break; | |
729 | case FL_FLOCK: | |
730 | res = flock_lock_file_wait(file, fl); | |
731 | break; | |
732 | default: | |
733 | BUG(); | |
734 | } | |
1da177e4 LT |
735 | return res; |
736 | } | |
737 | ||
5eebde23 SJ |
738 | static int |
739 | do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local) | |
1da177e4 LT |
740 | { |
741 | struct inode *inode = filp->f_mapping->host; | |
1da177e4 LT |
742 | int status; |
743 | ||
1da177e4 LT |
744 | /* |
745 | * Flush all pending writes before doing anything | |
746 | * with locks.. | |
747 | */ | |
29884df0 | 748 | nfs_sync_mapping(filp->f_mapping); |
1da177e4 LT |
749 | |
750 | /* NOTE: special case | |
751 | * If we're signalled while cleaning up locks on process exit, we | |
752 | * still need to complete the unlock. | |
753 | */ | |
5eebde23 SJ |
754 | /* |
755 | * Use local locking if mounted with "-onolock" or with appropriate | |
756 | * "-olocal_lock=" | |
757 | */ | |
758 | if (!is_local) | |
1da177e4 LT |
759 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); |
760 | else | |
761 | status = do_vfs_lock(filp, fl); | |
1da177e4 LT |
762 | return status; |
763 | } | |
764 | ||
6b96724e RL |
765 | static int |
766 | is_time_granular(struct timespec *ts) { | |
767 | return ((ts->tv_sec == 0) && (ts->tv_nsec <= 1000)); | |
768 | } | |
769 | ||
5eebde23 SJ |
770 | static int |
771 | do_setlk(struct file *filp, int cmd, struct file_lock *fl, int is_local) | |
1da177e4 LT |
772 | { |
773 | struct inode *inode = filp->f_mapping->host; | |
1da177e4 LT |
774 | int status; |
775 | ||
1da177e4 LT |
776 | /* |
777 | * Flush all pending writes before doing anything | |
778 | * with locks.. | |
779 | */ | |
29884df0 TM |
780 | status = nfs_sync_mapping(filp->f_mapping); |
781 | if (status != 0) | |
1da177e4 LT |
782 | goto out; |
783 | ||
5eebde23 SJ |
784 | /* |
785 | * Use local locking if mounted with "-onolock" or with appropriate | |
786 | * "-olocal_lock=" | |
787 | */ | |
788 | if (!is_local) | |
1da177e4 | 789 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); |
c4d7c402 | 790 | else |
1da177e4 | 791 | status = do_vfs_lock(filp, fl); |
1da177e4 LT |
792 | if (status < 0) |
793 | goto out; | |
6b96724e | 794 | |
1da177e4 | 795 | /* |
6b96724e RL |
796 | * Revalidate the cache if the server has time stamps granular |
797 | * enough to detect subsecond changes. Otherwise, clear the | |
798 | * cache to prevent missing any changes. | |
799 | * | |
1da177e4 LT |
800 | * This makes locking act as a cache coherency point. |
801 | */ | |
29884df0 | 802 | nfs_sync_mapping(filp->f_mapping); |
6b96724e RL |
803 | if (!nfs_have_delegation(inode, FMODE_READ)) { |
804 | if (is_time_granular(&NFS_SERVER(inode)->time_delta)) | |
805 | __nfs_revalidate_inode(NFS_SERVER(inode), inode); | |
806 | else | |
807 | nfs_zap_caches(inode); | |
808 | } | |
1da177e4 | 809 | out: |
1da177e4 LT |
810 | return status; |
811 | } | |
812 | ||
813 | /* | |
814 | * Lock a (portion of) a file | |
815 | */ | |
816 | static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl) | |
817 | { | |
6da24bc9 | 818 | struct inode *inode = filp->f_mapping->host; |
2116271a | 819 | int ret = -ENOLCK; |
5eebde23 | 820 | int is_local = 0; |
1da177e4 | 821 | |
6da24bc9 CL |
822 | dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n", |
823 | filp->f_path.dentry->d_parent->d_name.name, | |
824 | filp->f_path.dentry->d_name.name, | |
1da177e4 LT |
825 | fl->fl_type, fl->fl_flags, |
826 | (long long)fl->fl_start, (long long)fl->fl_end); | |
6da24bc9 | 827 | |
91d5b470 | 828 | nfs_inc_stats(inode, NFSIOS_VFSLOCK); |
1da177e4 LT |
829 | |
830 | /* No mandatory locks over NFS */ | |
dfad9441 | 831 | if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK) |
2116271a TM |
832 | goto out_err; |
833 | ||
5eebde23 SJ |
834 | if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FCNTL) |
835 | is_local = 1; | |
836 | ||
2116271a TM |
837 | if (NFS_PROTO(inode)->lock_check_bounds != NULL) { |
838 | ret = NFS_PROTO(inode)->lock_check_bounds(fl); | |
839 | if (ret < 0) | |
840 | goto out_err; | |
841 | } | |
1da177e4 LT |
842 | |
843 | if (IS_GETLK(cmd)) | |
5eebde23 | 844 | ret = do_getlk(filp, cmd, fl, is_local); |
2116271a | 845 | else if (fl->fl_type == F_UNLCK) |
5eebde23 | 846 | ret = do_unlk(filp, cmd, fl, is_local); |
2116271a | 847 | else |
5eebde23 | 848 | ret = do_setlk(filp, cmd, fl, is_local); |
2116271a TM |
849 | out_err: |
850 | return ret; | |
1da177e4 LT |
851 | } |
852 | ||
853 | /* | |
854 | * Lock a (portion of) a file | |
855 | */ | |
856 | static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl) | |
857 | { | |
5eebde23 SJ |
858 | struct inode *inode = filp->f_mapping->host; |
859 | int is_local = 0; | |
860 | ||
6da24bc9 CL |
861 | dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n", |
862 | filp->f_path.dentry->d_parent->d_name.name, | |
863 | filp->f_path.dentry->d_name.name, | |
1da177e4 LT |
864 | fl->fl_type, fl->fl_flags); |
865 | ||
1da177e4 LT |
866 | if (!(fl->fl_flags & FL_FLOCK)) |
867 | return -ENOLCK; | |
868 | ||
5eebde23 SJ |
869 | if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FLOCK) |
870 | is_local = 1; | |
871 | ||
1da177e4 LT |
872 | /* We're simulating flock() locks using posix locks on the server */ |
873 | fl->fl_owner = (fl_owner_t)filp; | |
874 | fl->fl_start = 0; | |
875 | fl->fl_end = OFFSET_MAX; | |
876 | ||
877 | if (fl->fl_type == F_UNLCK) | |
5eebde23 SJ |
878 | return do_unlk(filp, cmd, fl, is_local); |
879 | return do_setlk(filp, cmd, fl, is_local); | |
1da177e4 | 880 | } |
370f6599 | 881 | |
6da24bc9 CL |
882 | /* |
883 | * There is no protocol support for leases, so we have no way to implement | |
884 | * them correctly in the face of opens by other clients. | |
885 | */ | |
370f6599 BF |
886 | static int nfs_setlease(struct file *file, long arg, struct file_lock **fl) |
887 | { | |
6da24bc9 CL |
888 | dprintk("NFS: setlease(%s/%s, arg=%ld)\n", |
889 | file->f_path.dentry->d_parent->d_name.name, | |
890 | file->f_path.dentry->d_name.name, arg); | |
370f6599 BF |
891 | return -EINVAL; |
892 | } |