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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 | ||
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> |
e8edc6e0 | 29 | #include <linux/aio.h> |
5a0e3ad6 | 30 | #include <linux/gfp.h> |
b608b283 | 31 | #include <linux/swap.h> |
1da177e4 LT |
32 | |
33 | #include <asm/uaccess.h> | |
1da177e4 LT |
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 | ||
f0f37e2f | 42 | static const struct vm_operations_struct nfs_file_vm_ops; |
94387fb1 | 43 | |
1da177e4 LT |
44 | /* Hack for future NFS swap support */ |
45 | #ifndef IS_SWAPFILE | |
46 | # define IS_SWAPFILE(inode) (0) | |
47 | #endif | |
48 | ||
ce4ef7c0 | 49 | int nfs_check_flags(int flags) |
1da177e4 LT |
50 | { |
51 | if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT)) | |
52 | return -EINVAL; | |
53 | ||
54 | return 0; | |
55 | } | |
89d77c8f | 56 | EXPORT_SYMBOL_GPL(nfs_check_flags); |
1da177e4 LT |
57 | |
58 | /* | |
59 | * Open file | |
60 | */ | |
61 | static int | |
62 | nfs_file_open(struct inode *inode, struct file *filp) | |
63 | { | |
1da177e4 LT |
64 | int res; |
65 | ||
6da24bc9 | 66 | dprintk("NFS: open file(%s/%s)\n", |
cc0dd2d1 CL |
67 | filp->f_path.dentry->d_parent->d_name.name, |
68 | filp->f_path.dentry->d_name.name); | |
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 | 79 | int |
1da177e4 LT |
80 | nfs_file_release(struct inode *inode, struct file *filp) |
81 | { | |
6da24bc9 | 82 | dprintk("NFS: release(%s/%s)\n", |
6f276e49 RM |
83 | filp->f_path.dentry->d_parent->d_name.name, |
84 | filp->f_path.dentry->d_name.name); | |
6da24bc9 | 85 | |
91d5b470 | 86 | nfs_inc_stats(inode, NFSIOS_VFSRELEASE); |
46cb650c | 87 | return nfs_release(inode, filp); |
1da177e4 | 88 | } |
89d77c8f | 89 | EXPORT_SYMBOL_GPL(nfs_file_release); |
1da177e4 | 90 | |
980802e3 TM |
91 | /** |
92 | * nfs_revalidate_size - Revalidate the file size | |
93 | * @inode - pointer to inode struct | |
94 | * @file - pointer to struct file | |
95 | * | |
96 | * Revalidates the file length. This is basically a wrapper around | |
97 | * nfs_revalidate_inode() that takes into account the fact that we may | |
98 | * have cached writes (in which case we don't care about the server's | |
99 | * idea of what the file length is), or O_DIRECT (in which case we | |
100 | * shouldn't trust the cache). | |
101 | */ | |
102 | static int nfs_revalidate_file_size(struct inode *inode, struct file *filp) | |
103 | { | |
104 | struct nfs_server *server = NFS_SERVER(inode); | |
105 | struct nfs_inode *nfsi = NFS_I(inode); | |
106 | ||
d7cf8dd0 TM |
107 | if (nfs_have_delegated_attributes(inode)) |
108 | goto out_noreval; | |
109 | ||
980802e3 TM |
110 | if (filp->f_flags & O_DIRECT) |
111 | goto force_reval; | |
d7cf8dd0 TM |
112 | if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) |
113 | goto force_reval; | |
114 | if (nfs_attribute_timeout(inode)) | |
115 | goto force_reval; | |
116 | out_noreval: | |
117 | return 0; | |
980802e3 TM |
118 | force_reval: |
119 | return __nfs_revalidate_inode(server, inode); | |
120 | } | |
121 | ||
ce4ef7c0 | 122 | loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin) |
980802e3 | 123 | { |
6da24bc9 | 124 | dprintk("NFS: llseek file(%s/%s, %lld, %d)\n", |
b84e06c5 CL |
125 | filp->f_path.dentry->d_parent->d_name.name, |
126 | filp->f_path.dentry->d_name.name, | |
127 | offset, origin); | |
128 | ||
06222e49 JB |
129 | /* |
130 | * origin == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate | |
131 | * the cached file length | |
132 | */ | |
6c529617 | 133 | if (origin != SEEK_SET && origin != SEEK_CUR) { |
980802e3 | 134 | struct inode *inode = filp->f_mapping->host; |
d5e66348 | 135 | |
980802e3 TM |
136 | int retval = nfs_revalidate_file_size(inode, filp); |
137 | if (retval < 0) | |
138 | return (loff_t)retval; | |
79835a71 | 139 | } |
d5e66348 | 140 | |
79835a71 | 141 | return generic_file_llseek(filp, offset, origin); |
980802e3 | 142 | } |
89d77c8f | 143 | EXPORT_SYMBOL_GPL(nfs_file_llseek); |
980802e3 | 144 | |
1da177e4 LT |
145 | /* |
146 | * Flush all dirty pages, and check for write errors. | |
1da177e4 | 147 | */ |
ce4ef7c0 | 148 | int |
75e1fcc0 | 149 | nfs_file_flush(struct file *file, fl_owner_t id) |
1da177e4 | 150 | { |
6da24bc9 CL |
151 | struct dentry *dentry = file->f_path.dentry; |
152 | struct inode *inode = dentry->d_inode; | |
1da177e4 | 153 | |
6da24bc9 CL |
154 | dprintk("NFS: flush(%s/%s)\n", |
155 | dentry->d_parent->d_name.name, | |
156 | dentry->d_name.name); | |
1da177e4 | 157 | |
c2459dc4 | 158 | nfs_inc_stats(inode, NFSIOS_VFSFLUSH); |
1da177e4 LT |
159 | if ((file->f_mode & FMODE_WRITE) == 0) |
160 | return 0; | |
7b159fc1 | 161 | |
14546c33 TM |
162 | /* |
163 | * If we're holding a write delegation, then just start the i/o | |
164 | * but don't wait for completion (or send a commit). | |
165 | */ | |
011e2a7f | 166 | if (NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) |
14546c33 TM |
167 | return filemap_fdatawrite(file->f_mapping); |
168 | ||
7fe5c398 | 169 | /* Flush writes to the server and return any errors */ |
af7fa165 | 170 | return vfs_fsync(file, 0); |
1da177e4 | 171 | } |
89d77c8f | 172 | EXPORT_SYMBOL_GPL(nfs_file_flush); |
1da177e4 | 173 | |
ce4ef7c0 | 174 | ssize_t |
027445c3 BP |
175 | nfs_file_read(struct kiocb *iocb, const struct iovec *iov, |
176 | unsigned long nr_segs, loff_t pos) | |
1da177e4 | 177 | { |
01cce933 | 178 | struct dentry * dentry = iocb->ki_filp->f_path.dentry; |
1da177e4 LT |
179 | struct inode * inode = dentry->d_inode; |
180 | ssize_t result; | |
181 | ||
1da177e4 | 182 | if (iocb->ki_filp->f_flags & O_DIRECT) |
a564b8f0 | 183 | return nfs_file_direct_read(iocb, iov, nr_segs, pos, true); |
1da177e4 | 184 | |
6da24bc9 | 185 | dprintk("NFS: read(%s/%s, %lu@%lu)\n", |
1da177e4 | 186 | dentry->d_parent->d_name.name, dentry->d_name.name, |
6f276e49 | 187 | (unsigned long) iov_length(iov, nr_segs), (unsigned long) pos); |
1da177e4 | 188 | |
44b11874 | 189 | result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping); |
4184dcf2 | 190 | if (!result) { |
027445c3 | 191 | result = generic_file_aio_read(iocb, iov, nr_segs, pos); |
4184dcf2 CL |
192 | if (result > 0) |
193 | nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result); | |
194 | } | |
1da177e4 LT |
195 | return result; |
196 | } | |
89d77c8f | 197 | EXPORT_SYMBOL_GPL(nfs_file_read); |
1da177e4 | 198 | |
ce4ef7c0 | 199 | ssize_t |
f0930fff JA |
200 | nfs_file_splice_read(struct file *filp, loff_t *ppos, |
201 | struct pipe_inode_info *pipe, size_t count, | |
202 | unsigned int flags) | |
1da177e4 | 203 | { |
01cce933 | 204 | struct dentry *dentry = filp->f_path.dentry; |
1da177e4 LT |
205 | struct inode *inode = dentry->d_inode; |
206 | ssize_t res; | |
207 | ||
6da24bc9 | 208 | dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n", |
1da177e4 LT |
209 | dentry->d_parent->d_name.name, dentry->d_name.name, |
210 | (unsigned long) count, (unsigned long long) *ppos); | |
211 | ||
44b11874 | 212 | res = nfs_revalidate_mapping(inode, filp->f_mapping); |
aa2f1ef1 | 213 | if (!res) { |
f0930fff | 214 | res = generic_file_splice_read(filp, ppos, pipe, count, flags); |
aa2f1ef1 CL |
215 | if (res > 0) |
216 | nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, res); | |
217 | } | |
1da177e4 LT |
218 | return res; |
219 | } | |
89d77c8f | 220 | EXPORT_SYMBOL_GPL(nfs_file_splice_read); |
1da177e4 | 221 | |
ce4ef7c0 | 222 | int |
1da177e4 LT |
223 | nfs_file_mmap(struct file * file, struct vm_area_struct * vma) |
224 | { | |
01cce933 | 225 | struct dentry *dentry = file->f_path.dentry; |
1da177e4 LT |
226 | struct inode *inode = dentry->d_inode; |
227 | int status; | |
228 | ||
6da24bc9 | 229 | dprintk("NFS: mmap(%s/%s)\n", |
1da177e4 LT |
230 | dentry->d_parent->d_name.name, dentry->d_name.name); |
231 | ||
e1ebfd33 TM |
232 | /* Note: generic_file_mmap() returns ENOSYS on nommu systems |
233 | * so we call that before revalidating the mapping | |
234 | */ | |
235 | status = generic_file_mmap(file, vma); | |
94387fb1 TM |
236 | if (!status) { |
237 | vma->vm_ops = &nfs_file_vm_ops; | |
e1ebfd33 | 238 | status = nfs_revalidate_mapping(inode, file->f_mapping); |
94387fb1 | 239 | } |
1da177e4 LT |
240 | return status; |
241 | } | |
89d77c8f | 242 | EXPORT_SYMBOL_GPL(nfs_file_mmap); |
1da177e4 LT |
243 | |
244 | /* | |
245 | * Flush any dirty pages for this process, and check for write errors. | |
246 | * The return status from this call provides a reliable indication of | |
247 | * whether any write errors occurred for this process. | |
af7fa165 TM |
248 | * |
249 | * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to | |
250 | * disk, but it retrieves and clears ctx->error after synching, despite | |
251 | * the two being set at the same time in nfs_context_set_write_error(). | |
252 | * This is because the former is used to notify the _next_ call to | |
25985edc | 253 | * nfs_file_write() that a write error occurred, and hence cause it to |
af7fa165 | 254 | * fall back to doing a synchronous write. |
1da177e4 | 255 | */ |
ce4ef7c0 | 256 | int |
a5c58892 | 257 | nfs_file_fsync_commit(struct file *file, loff_t start, loff_t end, int datasync) |
1da177e4 | 258 | { |
7ea80859 | 259 | struct dentry *dentry = file->f_path.dentry; |
cd3758e3 | 260 | struct nfs_open_context *ctx = nfs_file_open_context(file); |
1da177e4 | 261 | struct inode *inode = dentry->d_inode; |
05990d1b | 262 | int have_error, do_resend, status; |
af7fa165 TM |
263 | int ret = 0; |
264 | ||
6da24bc9 | 265 | dprintk("NFS: fsync file(%s/%s) datasync %d\n", |
54917786 CL |
266 | dentry->d_parent->d_name.name, dentry->d_name.name, |
267 | datasync); | |
1da177e4 | 268 | |
91d5b470 | 269 | nfs_inc_stats(inode, NFSIOS_VFSFSYNC); |
05990d1b | 270 | do_resend = test_and_clear_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags); |
af7fa165 TM |
271 | have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); |
272 | status = nfs_commit_inode(inode, FLUSH_SYNC); | |
273 | have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); | |
05990d1b | 274 | if (have_error) { |
af7fa165 | 275 | ret = xchg(&ctx->error, 0); |
05990d1b TM |
276 | if (ret) |
277 | goto out; | |
278 | } | |
279 | if (status < 0) { | |
af7fa165 | 280 | ret = status; |
05990d1b TM |
281 | goto out; |
282 | } | |
283 | do_resend |= test_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags); | |
284 | if (do_resend) | |
285 | ret = -EAGAIN; | |
286 | out: | |
a5c58892 BS |
287 | return ret; |
288 | } | |
89d77c8f | 289 | EXPORT_SYMBOL_GPL(nfs_file_fsync_commit); |
a5c58892 BS |
290 | |
291 | static int | |
292 | nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync) | |
293 | { | |
294 | int ret; | |
295 | struct inode *inode = file->f_path.dentry->d_inode; | |
296 | ||
05990d1b TM |
297 | do { |
298 | ret = filemap_write_and_wait_range(inode->i_mapping, start, end); | |
299 | if (ret != 0) | |
300 | break; | |
301 | mutex_lock(&inode->i_mutex); | |
302 | ret = nfs_file_fsync_commit(file, start, end, datasync); | |
303 | mutex_unlock(&inode->i_mutex); | |
304 | } while (ret == -EAGAIN); | |
305 | ||
af7fa165 | 306 | return ret; |
1da177e4 LT |
307 | } |
308 | ||
38c73044 PS |
309 | /* |
310 | * Decide whether a read/modify/write cycle may be more efficient | |
311 | * then a modify/write/read cycle when writing to a page in the | |
312 | * page cache. | |
313 | * | |
314 | * The modify/write/read cycle may occur if a page is read before | |
315 | * being completely filled by the writer. In this situation, the | |
316 | * page must be completely written to stable storage on the server | |
317 | * before it can be refilled by reading in the page from the server. | |
318 | * This can lead to expensive, small, FILE_SYNC mode writes being | |
319 | * done. | |
320 | * | |
321 | * It may be more efficient to read the page first if the file is | |
322 | * open for reading in addition to writing, the page is not marked | |
323 | * as Uptodate, it is not dirty or waiting to be committed, | |
324 | * indicating that it was previously allocated and then modified, | |
325 | * that there were valid bytes of data in that range of the file, | |
326 | * and that the new data won't completely replace the old data in | |
327 | * that range of the file. | |
328 | */ | |
329 | static int nfs_want_read_modify_write(struct file *file, struct page *page, | |
330 | loff_t pos, unsigned len) | |
331 | { | |
332 | unsigned int pglen = nfs_page_length(page); | |
333 | unsigned int offset = pos & (PAGE_CACHE_SIZE - 1); | |
334 | unsigned int end = offset + len; | |
335 | ||
336 | if ((file->f_mode & FMODE_READ) && /* open for read? */ | |
337 | !PageUptodate(page) && /* Uptodate? */ | |
338 | !PagePrivate(page) && /* i/o request already? */ | |
339 | pglen && /* valid bytes of file? */ | |
340 | (end < pglen || offset)) /* replace all valid bytes? */ | |
341 | return 1; | |
342 | return 0; | |
343 | } | |
344 | ||
1da177e4 | 345 | /* |
4899f9c8 NP |
346 | * This does the "real" work of the write. We must allocate and lock the |
347 | * page to be sent back to the generic routine, which then copies the | |
348 | * data from user space. | |
1da177e4 LT |
349 | * |
350 | * If the writer ends up delaying the write, the writer needs to | |
351 | * increment the page use counts until he is done with the page. | |
352 | */ | |
4899f9c8 NP |
353 | static int nfs_write_begin(struct file *file, struct address_space *mapping, |
354 | loff_t pos, unsigned len, unsigned flags, | |
355 | struct page **pagep, void **fsdata) | |
1da177e4 | 356 | { |
4899f9c8 | 357 | int ret; |
38c73044 | 358 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
4899f9c8 | 359 | struct page *page; |
38c73044 | 360 | int once_thru = 0; |
4899f9c8 | 361 | |
b7eaefaa CL |
362 | dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n", |
363 | file->f_path.dentry->d_parent->d_name.name, | |
364 | file->f_path.dentry->d_name.name, | |
365 | mapping->host->i_ino, len, (long long) pos); | |
366 | ||
38c73044 | 367 | start: |
72cb77f4 TM |
368 | /* |
369 | * Prevent starvation issues if someone is doing a consistency | |
370 | * sync-to-disk | |
371 | */ | |
372 | ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING, | |
373 | nfs_wait_bit_killable, TASK_KILLABLE); | |
374 | if (ret) | |
375 | return ret; | |
376 | ||
54566b2c | 377 | page = grab_cache_page_write_begin(mapping, index, flags); |
4899f9c8 NP |
378 | if (!page) |
379 | return -ENOMEM; | |
380 | *pagep = page; | |
381 | ||
382 | ret = nfs_flush_incompatible(file, page); | |
383 | if (ret) { | |
384 | unlock_page(page); | |
385 | page_cache_release(page); | |
38c73044 PS |
386 | } else if (!once_thru && |
387 | nfs_want_read_modify_write(file, page, pos, len)) { | |
388 | once_thru = 1; | |
389 | ret = nfs_readpage(file, page); | |
390 | page_cache_release(page); | |
391 | if (!ret) | |
392 | goto start; | |
4899f9c8 NP |
393 | } |
394 | return ret; | |
1da177e4 LT |
395 | } |
396 | ||
4899f9c8 NP |
397 | static int nfs_write_end(struct file *file, struct address_space *mapping, |
398 | loff_t pos, unsigned len, unsigned copied, | |
399 | struct page *page, void *fsdata) | |
1da177e4 | 400 | { |
4899f9c8 NP |
401 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); |
402 | int status; | |
1da177e4 | 403 | |
b7eaefaa CL |
404 | dfprintk(PAGECACHE, "NFS: write_end(%s/%s(%ld), %u@%lld)\n", |
405 | file->f_path.dentry->d_parent->d_name.name, | |
406 | file->f_path.dentry->d_name.name, | |
407 | mapping->host->i_ino, len, (long long) pos); | |
408 | ||
efc91ed0 TM |
409 | /* |
410 | * Zero any uninitialised parts of the page, and then mark the page | |
411 | * as up to date if it turns out that we're extending the file. | |
412 | */ | |
413 | if (!PageUptodate(page)) { | |
414 | unsigned pglen = nfs_page_length(page); | |
415 | unsigned end = offset + len; | |
416 | ||
417 | if (pglen == 0) { | |
418 | zero_user_segments(page, 0, offset, | |
419 | end, PAGE_CACHE_SIZE); | |
420 | SetPageUptodate(page); | |
421 | } else if (end >= pglen) { | |
422 | zero_user_segment(page, end, PAGE_CACHE_SIZE); | |
423 | if (offset == 0) | |
424 | SetPageUptodate(page); | |
425 | } else | |
426 | zero_user_segment(page, pglen, PAGE_CACHE_SIZE); | |
427 | } | |
428 | ||
4899f9c8 | 429 | status = nfs_updatepage(file, page, offset, copied); |
4899f9c8 NP |
430 | |
431 | unlock_page(page); | |
432 | page_cache_release(page); | |
433 | ||
3d509e54 CL |
434 | if (status < 0) |
435 | return status; | |
2701d086 | 436 | NFS_I(mapping->host)->write_io += copied; |
3d509e54 | 437 | return copied; |
1da177e4 LT |
438 | } |
439 | ||
6b9b3514 DH |
440 | /* |
441 | * Partially or wholly invalidate a page | |
442 | * - Release the private state associated with a page if undergoing complete | |
443 | * page invalidation | |
545db45f | 444 | * - Called if either PG_private or PG_fscache is set on the page |
6b9b3514 DH |
445 | * - Caller holds page lock |
446 | */ | |
2ff28e22 | 447 | static void nfs_invalidate_page(struct page *page, unsigned long offset) |
cd52ed35 | 448 | { |
b7eaefaa CL |
449 | dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset); |
450 | ||
1c75950b TM |
451 | if (offset != 0) |
452 | return; | |
d2ccddf0 | 453 | /* Cancel any unstarted writes on this page */ |
d56b4ddf | 454 | nfs_wb_page_cancel(page_file_mapping(page)->host, page); |
545db45f DH |
455 | |
456 | nfs_fscache_invalidate_page(page, page->mapping->host); | |
cd52ed35 TM |
457 | } |
458 | ||
6b9b3514 DH |
459 | /* |
460 | * Attempt to release the private state associated with a page | |
545db45f | 461 | * - Called if either PG_private or PG_fscache is set on the page |
6b9b3514 DH |
462 | * - Caller holds page lock |
463 | * - Return true (may release page) or false (may not) | |
464 | */ | |
cd52ed35 TM |
465 | static int nfs_release_page(struct page *page, gfp_t gfp) |
466 | { | |
b608b283 TM |
467 | struct address_space *mapping = page->mapping; |
468 | ||
b7eaefaa CL |
469 | dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page); |
470 | ||
5cf02d09 JL |
471 | /* Only do I/O if gfp is a superset of GFP_KERNEL, and we're not |
472 | * doing this memory reclaim for a fs-related allocation. | |
473 | */ | |
474 | if (mapping && (gfp & GFP_KERNEL) == GFP_KERNEL && | |
475 | !(current->flags & PF_FSTRANS)) { | |
b608b283 TM |
476 | int how = FLUSH_SYNC; |
477 | ||
478 | /* Don't let kswapd deadlock waiting for OOM RPC calls */ | |
479 | if (current_is_kswapd()) | |
480 | how = 0; | |
481 | nfs_commit_inode(mapping->host, how); | |
482 | } | |
e3db7691 | 483 | /* If PagePrivate() is set, then the page is not freeable */ |
545db45f DH |
484 | if (PagePrivate(page)) |
485 | return 0; | |
486 | return nfs_fscache_release_page(page, gfp); | |
e3db7691 TM |
487 | } |
488 | ||
6b9b3514 DH |
489 | /* |
490 | * Attempt to clear the private state associated with a page when an error | |
491 | * occurs that requires the cached contents of an inode to be written back or | |
492 | * destroyed | |
545db45f | 493 | * - Called if either PG_private or fscache is set on the page |
6b9b3514 DH |
494 | * - Caller holds page lock |
495 | * - Return 0 if successful, -error otherwise | |
496 | */ | |
e3db7691 TM |
497 | static int nfs_launder_page(struct page *page) |
498 | { | |
d56b4ddf | 499 | struct inode *inode = page_file_mapping(page)->host; |
545db45f | 500 | struct nfs_inode *nfsi = NFS_I(inode); |
b7eaefaa CL |
501 | |
502 | dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n", | |
503 | inode->i_ino, (long long)page_offset(page)); | |
504 | ||
545db45f | 505 | nfs_fscache_wait_on_page_write(nfsi, page); |
b7eaefaa | 506 | return nfs_wb_page(inode, page); |
cd52ed35 TM |
507 | } |
508 | ||
a564b8f0 MG |
509 | #ifdef CONFIG_NFS_SWAP |
510 | static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file, | |
511 | sector_t *span) | |
512 | { | |
513 | *span = sis->pages; | |
514 | return xs_swapper(NFS_CLIENT(file->f_mapping->host)->cl_xprt, 1); | |
515 | } | |
516 | ||
517 | static void nfs_swap_deactivate(struct file *file) | |
518 | { | |
519 | xs_swapper(NFS_CLIENT(file->f_mapping->host)->cl_xprt, 0); | |
520 | } | |
521 | #endif | |
522 | ||
f5e54d6e | 523 | const struct address_space_operations nfs_file_aops = { |
1da177e4 LT |
524 | .readpage = nfs_readpage, |
525 | .readpages = nfs_readpages, | |
9cccef95 | 526 | .set_page_dirty = __set_page_dirty_nobuffers, |
1da177e4 LT |
527 | .writepage = nfs_writepage, |
528 | .writepages = nfs_writepages, | |
4899f9c8 NP |
529 | .write_begin = nfs_write_begin, |
530 | .write_end = nfs_write_end, | |
cd52ed35 TM |
531 | .invalidatepage = nfs_invalidate_page, |
532 | .releasepage = nfs_release_page, | |
1da177e4 | 533 | .direct_IO = nfs_direct_IO, |
074cc1de | 534 | .migratepage = nfs_migrate_page, |
e3db7691 | 535 | .launder_page = nfs_launder_page, |
f590f333 | 536 | .error_remove_page = generic_error_remove_page, |
a564b8f0 MG |
537 | #ifdef CONFIG_NFS_SWAP |
538 | .swap_activate = nfs_swap_activate, | |
539 | .swap_deactivate = nfs_swap_deactivate, | |
540 | #endif | |
1da177e4 LT |
541 | }; |
542 | ||
6b9b3514 DH |
543 | /* |
544 | * Notification that a PTE pointing to an NFS page is about to be made | |
545 | * writable, implying that someone is about to modify the page through a | |
546 | * shared-writable mapping | |
547 | */ | |
c2ec175c | 548 | static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
94387fb1 | 549 | { |
c2ec175c | 550 | struct page *page = vmf->page; |
94387fb1 | 551 | struct file *filp = vma->vm_file; |
b7eaefaa | 552 | struct dentry *dentry = filp->f_path.dentry; |
94387fb1 | 553 | unsigned pagelen; |
bc4866b6 | 554 | int ret = VM_FAULT_NOPAGE; |
4899f9c8 | 555 | struct address_space *mapping; |
94387fb1 | 556 | |
b7eaefaa CL |
557 | dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n", |
558 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
559 | filp->f_mapping->host->i_ino, | |
560 | (long long)page_offset(page)); | |
561 | ||
545db45f DH |
562 | /* make sure the cache has finished storing the page */ |
563 | nfs_fscache_wait_on_page_write(NFS_I(dentry->d_inode), page); | |
564 | ||
94387fb1 | 565 | lock_page(page); |
d56b4ddf | 566 | mapping = page_file_mapping(page); |
b7eaefaa | 567 | if (mapping != dentry->d_inode->i_mapping) |
8b1f9ee5 TM |
568 | goto out_unlock; |
569 | ||
2aeb98f4 TM |
570 | wait_on_page_writeback(page); |
571 | ||
94387fb1 | 572 | pagelen = nfs_page_length(page); |
8b1f9ee5 TM |
573 | if (pagelen == 0) |
574 | goto out_unlock; | |
4899f9c8 | 575 | |
bc4866b6 TM |
576 | ret = VM_FAULT_LOCKED; |
577 | if (nfs_flush_incompatible(filp, page) == 0 && | |
578 | nfs_updatepage(filp, page, 0, pagelen) == 0) | |
579 | goto out; | |
8b1f9ee5 | 580 | |
bc4866b6 | 581 | ret = VM_FAULT_SIGBUS; |
8b1f9ee5 TM |
582 | out_unlock: |
583 | unlock_page(page); | |
bc4866b6 TM |
584 | out: |
585 | return ret; | |
94387fb1 TM |
586 | } |
587 | ||
f0f37e2f | 588 | static const struct vm_operations_struct nfs_file_vm_ops = { |
94387fb1 TM |
589 | .fault = filemap_fault, |
590 | .page_mkwrite = nfs_vm_page_mkwrite, | |
591 | }; | |
592 | ||
7b159fc1 TM |
593 | static int nfs_need_sync_write(struct file *filp, struct inode *inode) |
594 | { | |
595 | struct nfs_open_context *ctx; | |
596 | ||
6b2f3d1f | 597 | if (IS_SYNC(inode) || (filp->f_flags & O_DSYNC)) |
7b159fc1 | 598 | return 1; |
cd3758e3 | 599 | ctx = nfs_file_open_context(filp); |
7b159fc1 TM |
600 | if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags)) |
601 | return 1; | |
602 | return 0; | |
603 | } | |
604 | ||
ce4ef7c0 BS |
605 | ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov, |
606 | unsigned long nr_segs, loff_t pos) | |
1da177e4 | 607 | { |
01cce933 | 608 | struct dentry * dentry = iocb->ki_filp->f_path.dentry; |
1da177e4 | 609 | struct inode * inode = dentry->d_inode; |
7e381172 | 610 | unsigned long written = 0; |
1da177e4 | 611 | ssize_t result; |
027445c3 | 612 | size_t count = iov_length(iov, nr_segs); |
1da177e4 | 613 | |
1da177e4 | 614 | if (iocb->ki_filp->f_flags & O_DIRECT) |
a564b8f0 | 615 | return nfs_file_direct_write(iocb, iov, nr_segs, pos, true); |
1da177e4 | 616 | |
6da24bc9 | 617 | dprintk("NFS: write(%s/%s, %lu@%Ld)\n", |
1da177e4 | 618 | dentry->d_parent->d_name.name, dentry->d_name.name, |
6da24bc9 | 619 | (unsigned long) count, (long long) pos); |
1da177e4 LT |
620 | |
621 | result = -EBUSY; | |
622 | if (IS_SWAPFILE(inode)) | |
623 | goto out_swapfile; | |
7d52e862 TM |
624 | /* |
625 | * O_APPEND implies that we must revalidate the file length. | |
626 | */ | |
627 | if (iocb->ki_filp->f_flags & O_APPEND) { | |
628 | result = nfs_revalidate_file_size(inode, iocb->ki_filp); | |
629 | if (result) | |
630 | goto out; | |
fe51beec | 631 | } |
1da177e4 LT |
632 | |
633 | result = count; | |
634 | if (!count) | |
635 | goto out; | |
636 | ||
027445c3 | 637 | result = generic_file_aio_write(iocb, iov, nr_segs, pos); |
7e381172 CL |
638 | if (result > 0) |
639 | written = result; | |
640 | ||
6b2f3d1f | 641 | /* Return error values for O_DSYNC and IS_SYNC() */ |
7b159fc1 | 642 | if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) { |
af7fa165 | 643 | int err = vfs_fsync(iocb->ki_filp, 0); |
200baa21 TM |
644 | if (err < 0) |
645 | result = err; | |
646 | } | |
7e381172 CL |
647 | if (result > 0) |
648 | nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written); | |
1da177e4 LT |
649 | out: |
650 | return result; | |
651 | ||
652 | out_swapfile: | |
653 | printk(KERN_INFO "NFS: attempt to write to active swap file!\n"); | |
654 | goto out; | |
655 | } | |
89d77c8f | 656 | EXPORT_SYMBOL_GPL(nfs_file_write); |
1da177e4 | 657 | |
ce4ef7c0 BS |
658 | ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe, |
659 | struct file *filp, loff_t *ppos, | |
660 | size_t count, unsigned int flags) | |
bf40d343 SJ |
661 | { |
662 | struct dentry *dentry = filp->f_path.dentry; | |
663 | struct inode *inode = dentry->d_inode; | |
7e381172 | 664 | unsigned long written = 0; |
bf40d343 SJ |
665 | ssize_t ret; |
666 | ||
667 | dprintk("NFS splice_write(%s/%s, %lu@%llu)\n", | |
668 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
669 | (unsigned long) count, (unsigned long long) *ppos); | |
670 | ||
671 | /* | |
672 | * The combination of splice and an O_APPEND destination is disallowed. | |
673 | */ | |
674 | ||
bf40d343 | 675 | ret = generic_file_splice_write(pipe, filp, ppos, count, flags); |
7e381172 CL |
676 | if (ret > 0) |
677 | written = ret; | |
678 | ||
bf40d343 | 679 | if (ret >= 0 && nfs_need_sync_write(filp, inode)) { |
af7fa165 | 680 | int err = vfs_fsync(filp, 0); |
bf40d343 SJ |
681 | if (err < 0) |
682 | ret = err; | |
683 | } | |
7e381172 CL |
684 | if (ret > 0) |
685 | nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written); | |
bf40d343 SJ |
686 | return ret; |
687 | } | |
89d77c8f | 688 | EXPORT_SYMBOL_GPL(nfs_file_splice_write); |
bf40d343 | 689 | |
5eebde23 SJ |
690 | static int |
691 | do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local) | |
1da177e4 LT |
692 | { |
693 | struct inode *inode = filp->f_mapping->host; | |
694 | int status = 0; | |
21ac19d4 | 695 | unsigned int saved_type = fl->fl_type; |
1da177e4 | 696 | |
039c4d7a | 697 | /* Try local locking first */ |
6d34ac19 BF |
698 | posix_test_lock(filp, fl); |
699 | if (fl->fl_type != F_UNLCK) { | |
700 | /* found a conflict */ | |
039c4d7a | 701 | goto out; |
1da177e4 | 702 | } |
21ac19d4 | 703 | fl->fl_type = saved_type; |
039c4d7a | 704 | |
011e2a7f | 705 | if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ)) |
039c4d7a TM |
706 | goto out_noconflict; |
707 | ||
5eebde23 | 708 | if (is_local) |
039c4d7a TM |
709 | goto out_noconflict; |
710 | ||
711 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); | |
712 | out: | |
1da177e4 | 713 | return status; |
039c4d7a TM |
714 | out_noconflict: |
715 | fl->fl_type = F_UNLCK; | |
716 | goto out; | |
1da177e4 LT |
717 | } |
718 | ||
719 | static int do_vfs_lock(struct file *file, struct file_lock *fl) | |
720 | { | |
721 | int res = 0; | |
722 | switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) { | |
723 | case FL_POSIX: | |
724 | res = posix_lock_file_wait(file, fl); | |
725 | break; | |
726 | case FL_FLOCK: | |
727 | res = flock_lock_file_wait(file, fl); | |
728 | break; | |
729 | default: | |
730 | BUG(); | |
731 | } | |
1da177e4 LT |
732 | return res; |
733 | } | |
734 | ||
5eebde23 SJ |
735 | static int |
736 | do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local) | |
1da177e4 LT |
737 | { |
738 | struct inode *inode = filp->f_mapping->host; | |
1da177e4 LT |
739 | int status; |
740 | ||
1da177e4 LT |
741 | /* |
742 | * Flush all pending writes before doing anything | |
743 | * with locks.. | |
744 | */ | |
29884df0 | 745 | nfs_sync_mapping(filp->f_mapping); |
1da177e4 LT |
746 | |
747 | /* NOTE: special case | |
748 | * If we're signalled while cleaning up locks on process exit, we | |
749 | * still need to complete the unlock. | |
750 | */ | |
5eebde23 SJ |
751 | /* |
752 | * Use local locking if mounted with "-onolock" or with appropriate | |
753 | * "-olocal_lock=" | |
754 | */ | |
755 | if (!is_local) | |
1da177e4 LT |
756 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); |
757 | else | |
758 | status = do_vfs_lock(filp, fl); | |
1da177e4 LT |
759 | return status; |
760 | } | |
761 | ||
6b96724e RL |
762 | static int |
763 | is_time_granular(struct timespec *ts) { | |
764 | return ((ts->tv_sec == 0) && (ts->tv_nsec <= 1000)); | |
765 | } | |
766 | ||
5eebde23 SJ |
767 | static int |
768 | do_setlk(struct file *filp, int cmd, struct file_lock *fl, int is_local) | |
1da177e4 LT |
769 | { |
770 | struct inode *inode = filp->f_mapping->host; | |
1da177e4 LT |
771 | int status; |
772 | ||
1da177e4 LT |
773 | /* |
774 | * Flush all pending writes before doing anything | |
775 | * with locks.. | |
776 | */ | |
29884df0 TM |
777 | status = nfs_sync_mapping(filp->f_mapping); |
778 | if (status != 0) | |
1da177e4 LT |
779 | goto out; |
780 | ||
5eebde23 SJ |
781 | /* |
782 | * Use local locking if mounted with "-onolock" or with appropriate | |
783 | * "-olocal_lock=" | |
784 | */ | |
785 | if (!is_local) | |
1da177e4 | 786 | status = NFS_PROTO(inode)->lock(filp, cmd, fl); |
c4d7c402 | 787 | else |
1da177e4 | 788 | status = do_vfs_lock(filp, fl); |
1da177e4 LT |
789 | if (status < 0) |
790 | goto out; | |
6b96724e | 791 | |
1da177e4 | 792 | /* |
6b96724e RL |
793 | * Revalidate the cache if the server has time stamps granular |
794 | * enough to detect subsecond changes. Otherwise, clear the | |
795 | * cache to prevent missing any changes. | |
796 | * | |
1da177e4 LT |
797 | * This makes locking act as a cache coherency point. |
798 | */ | |
29884df0 | 799 | nfs_sync_mapping(filp->f_mapping); |
011e2a7f | 800 | if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ)) { |
6b96724e RL |
801 | if (is_time_granular(&NFS_SERVER(inode)->time_delta)) |
802 | __nfs_revalidate_inode(NFS_SERVER(inode), inode); | |
803 | else | |
804 | nfs_zap_caches(inode); | |
805 | } | |
1da177e4 | 806 | out: |
1da177e4 LT |
807 | return status; |
808 | } | |
809 | ||
810 | /* | |
811 | * Lock a (portion of) a file | |
812 | */ | |
ce4ef7c0 | 813 | int nfs_lock(struct file *filp, int cmd, struct file_lock *fl) |
1da177e4 | 814 | { |
6da24bc9 | 815 | struct inode *inode = filp->f_mapping->host; |
2116271a | 816 | int ret = -ENOLCK; |
5eebde23 | 817 | int is_local = 0; |
1da177e4 | 818 | |
6da24bc9 CL |
819 | dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n", |
820 | filp->f_path.dentry->d_parent->d_name.name, | |
821 | filp->f_path.dentry->d_name.name, | |
1da177e4 LT |
822 | fl->fl_type, fl->fl_flags, |
823 | (long long)fl->fl_start, (long long)fl->fl_end); | |
6da24bc9 | 824 | |
91d5b470 | 825 | nfs_inc_stats(inode, NFSIOS_VFSLOCK); |
1da177e4 LT |
826 | |
827 | /* No mandatory locks over NFS */ | |
dfad9441 | 828 | if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK) |
2116271a TM |
829 | goto out_err; |
830 | ||
5eebde23 SJ |
831 | if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FCNTL) |
832 | is_local = 1; | |
833 | ||
2116271a TM |
834 | if (NFS_PROTO(inode)->lock_check_bounds != NULL) { |
835 | ret = NFS_PROTO(inode)->lock_check_bounds(fl); | |
836 | if (ret < 0) | |
837 | goto out_err; | |
838 | } | |
1da177e4 LT |
839 | |
840 | if (IS_GETLK(cmd)) | |
5eebde23 | 841 | ret = do_getlk(filp, cmd, fl, is_local); |
2116271a | 842 | else if (fl->fl_type == F_UNLCK) |
5eebde23 | 843 | ret = do_unlk(filp, cmd, fl, is_local); |
2116271a | 844 | else |
5eebde23 | 845 | ret = do_setlk(filp, cmd, fl, is_local); |
2116271a TM |
846 | out_err: |
847 | return ret; | |
1da177e4 | 848 | } |
89d77c8f | 849 | EXPORT_SYMBOL_GPL(nfs_lock); |
1da177e4 LT |
850 | |
851 | /* | |
852 | * Lock a (portion of) a file | |
853 | */ | |
ce4ef7c0 | 854 | int nfs_flock(struct file *filp, int cmd, struct file_lock *fl) |
1da177e4 | 855 | { |
5eebde23 SJ |
856 | struct inode *inode = filp->f_mapping->host; |
857 | int is_local = 0; | |
858 | ||
6da24bc9 CL |
859 | dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n", |
860 | filp->f_path.dentry->d_parent->d_name.name, | |
861 | filp->f_path.dentry->d_name.name, | |
1da177e4 LT |
862 | fl->fl_type, fl->fl_flags); |
863 | ||
1da177e4 LT |
864 | if (!(fl->fl_flags & FL_FLOCK)) |
865 | return -ENOLCK; | |
866 | ||
ad0fcd4e JL |
867 | /* |
868 | * The NFSv4 protocol doesn't support LOCK_MAND, which is not part of | |
869 | * any standard. In principle we might be able to support LOCK_MAND | |
870 | * on NFSv2/3 since NLMv3/4 support DOS share modes, but for now the | |
871 | * NFS code is not set up for it. | |
872 | */ | |
873 | if (fl->fl_type & LOCK_MAND) | |
874 | return -EINVAL; | |
875 | ||
5eebde23 SJ |
876 | if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FLOCK) |
877 | is_local = 1; | |
878 | ||
1da177e4 LT |
879 | /* We're simulating flock() locks using posix locks on the server */ |
880 | fl->fl_owner = (fl_owner_t)filp; | |
881 | fl->fl_start = 0; | |
882 | fl->fl_end = OFFSET_MAX; | |
883 | ||
884 | if (fl->fl_type == F_UNLCK) | |
5eebde23 SJ |
885 | return do_unlk(filp, cmd, fl, is_local); |
886 | return do_setlk(filp, cmd, fl, is_local); | |
1da177e4 | 887 | } |
89d77c8f | 888 | EXPORT_SYMBOL_GPL(nfs_flock); |
370f6599 | 889 | |
6da24bc9 CL |
890 | /* |
891 | * There is no protocol support for leases, so we have no way to implement | |
892 | * them correctly in the face of opens by other clients. | |
893 | */ | |
ce4ef7c0 | 894 | int nfs_setlease(struct file *file, long arg, struct file_lock **fl) |
370f6599 | 895 | { |
6da24bc9 CL |
896 | dprintk("NFS: setlease(%s/%s, arg=%ld)\n", |
897 | file->f_path.dentry->d_parent->d_name.name, | |
898 | file->f_path.dentry->d_name.name, arg); | |
370f6599 BF |
899 | return -EINVAL; |
900 | } | |
89d77c8f | 901 | EXPORT_SYMBOL_GPL(nfs_setlease); |
1788ea6e | 902 | |
0486958f JL |
903 | const struct file_operations nfs_file_operations = { |
904 | .llseek = nfs_file_llseek, | |
905 | .read = do_sync_read, | |
906 | .write = do_sync_write, | |
907 | .aio_read = nfs_file_read, | |
908 | .aio_write = nfs_file_write, | |
909 | .mmap = nfs_file_mmap, | |
910 | .open = nfs_file_open, | |
911 | .flush = nfs_file_flush, | |
912 | .release = nfs_file_release, | |
913 | .fsync = nfs_file_fsync, | |
914 | .lock = nfs_lock, | |
915 | .flock = nfs_flock, | |
916 | .splice_read = nfs_file_splice_read, | |
917 | .splice_write = nfs_file_splice_write, | |
918 | .check_flags = nfs_check_flags, | |
919 | .setlease = nfs_setlease, | |
920 | }; | |
ddda8e0a | 921 | EXPORT_SYMBOL_GPL(nfs_file_operations); |