]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/nfs/dir.c | |
3 | * | |
4 | * Copyright (C) 1992 Rick Sladkey | |
5 | * | |
6 | * nfs directory handling functions | |
7 | * | |
8 | * 10 Apr 1996 Added silly rename for unlink --okir | |
9 | * 28 Sep 1996 Improved directory cache --okir | |
10 | * 23 Aug 1997 Claus Heine claus@momo.math.rwth-aachen.de | |
11 | * Re-implemented silly rename for unlink, newly implemented | |
12 | * silly rename for nfs_rename() following the suggestions | |
13 | * of Olaf Kirch (okir) found in this file. | |
14 | * Following Linus comments on my original hack, this version | |
15 | * depends only on the dcache stuff and doesn't touch the inode | |
16 | * layer (iput() and friends). | |
17 | * 6 Jun 1999 Cache readdir lookups in the page cache. -DaveM | |
18 | */ | |
19 | ||
20 | #include <linux/time.h> | |
21 | #include <linux/errno.h> | |
22 | #include <linux/stat.h> | |
23 | #include <linux/fcntl.h> | |
24 | #include <linux/string.h> | |
25 | #include <linux/kernel.h> | |
26 | #include <linux/slab.h> | |
27 | #include <linux/mm.h> | |
28 | #include <linux/sunrpc/clnt.h> | |
29 | #include <linux/nfs_fs.h> | |
30 | #include <linux/nfs_mount.h> | |
31 | #include <linux/pagemap.h> | |
32 | #include <linux/smp_lock.h> | |
873101b3 | 33 | #include <linux/pagevec.h> |
1da177e4 | 34 | #include <linux/namei.h> |
54ceac45 | 35 | #include <linux/mount.h> |
e8edc6e0 | 36 | #include <linux/sched.h> |
1da177e4 | 37 | |
4ce79717 | 38 | #include "nfs4_fs.h" |
1da177e4 | 39 | #include "delegation.h" |
91d5b470 | 40 | #include "iostat.h" |
1da177e4 | 41 | |
1da177e4 LT |
42 | /* #define NFS_DEBUG_VERBOSE 1 */ |
43 | ||
44 | static int nfs_opendir(struct inode *, struct file *); | |
45 | static int nfs_readdir(struct file *, void *, filldir_t); | |
46 | static struct dentry *nfs_lookup(struct inode *, struct dentry *, struct nameidata *); | |
47 | static int nfs_create(struct inode *, struct dentry *, int, struct nameidata *); | |
48 | static int nfs_mkdir(struct inode *, struct dentry *, int); | |
49 | static int nfs_rmdir(struct inode *, struct dentry *); | |
50 | static int nfs_unlink(struct inode *, struct dentry *); | |
51 | static int nfs_symlink(struct inode *, struct dentry *, const char *); | |
52 | static int nfs_link(struct dentry *, struct inode *, struct dentry *); | |
53 | static int nfs_mknod(struct inode *, struct dentry *, int, dev_t); | |
54 | static int nfs_rename(struct inode *, struct dentry *, | |
55 | struct inode *, struct dentry *); | |
56 | static int nfs_fsync_dir(struct file *, struct dentry *, int); | |
f0dd2136 | 57 | static loff_t nfs_llseek_dir(struct file *, loff_t, int); |
1da177e4 | 58 | |
4b6f5d20 | 59 | const struct file_operations nfs_dir_operations = { |
f0dd2136 | 60 | .llseek = nfs_llseek_dir, |
1da177e4 LT |
61 | .read = generic_read_dir, |
62 | .readdir = nfs_readdir, | |
63 | .open = nfs_opendir, | |
64 | .release = nfs_release, | |
65 | .fsync = nfs_fsync_dir, | |
66 | }; | |
67 | ||
92e1d5be | 68 | const struct inode_operations nfs_dir_inode_operations = { |
1da177e4 LT |
69 | .create = nfs_create, |
70 | .lookup = nfs_lookup, | |
71 | .link = nfs_link, | |
72 | .unlink = nfs_unlink, | |
73 | .symlink = nfs_symlink, | |
74 | .mkdir = nfs_mkdir, | |
75 | .rmdir = nfs_rmdir, | |
76 | .mknod = nfs_mknod, | |
77 | .rename = nfs_rename, | |
78 | .permission = nfs_permission, | |
79 | .getattr = nfs_getattr, | |
80 | .setattr = nfs_setattr, | |
81 | }; | |
82 | ||
b7fa0554 | 83 | #ifdef CONFIG_NFS_V3 |
92e1d5be | 84 | const struct inode_operations nfs3_dir_inode_operations = { |
b7fa0554 AG |
85 | .create = nfs_create, |
86 | .lookup = nfs_lookup, | |
87 | .link = nfs_link, | |
88 | .unlink = nfs_unlink, | |
89 | .symlink = nfs_symlink, | |
90 | .mkdir = nfs_mkdir, | |
91 | .rmdir = nfs_rmdir, | |
92 | .mknod = nfs_mknod, | |
93 | .rename = nfs_rename, | |
94 | .permission = nfs_permission, | |
95 | .getattr = nfs_getattr, | |
96 | .setattr = nfs_setattr, | |
97 | .listxattr = nfs3_listxattr, | |
98 | .getxattr = nfs3_getxattr, | |
99 | .setxattr = nfs3_setxattr, | |
100 | .removexattr = nfs3_removexattr, | |
101 | }; | |
102 | #endif /* CONFIG_NFS_V3 */ | |
103 | ||
1da177e4 LT |
104 | #ifdef CONFIG_NFS_V4 |
105 | ||
106 | static struct dentry *nfs_atomic_lookup(struct inode *, struct dentry *, struct nameidata *); | |
92e1d5be | 107 | const struct inode_operations nfs4_dir_inode_operations = { |
1da177e4 LT |
108 | .create = nfs_create, |
109 | .lookup = nfs_atomic_lookup, | |
110 | .link = nfs_link, | |
111 | .unlink = nfs_unlink, | |
112 | .symlink = nfs_symlink, | |
113 | .mkdir = nfs_mkdir, | |
114 | .rmdir = nfs_rmdir, | |
115 | .mknod = nfs_mknod, | |
116 | .rename = nfs_rename, | |
117 | .permission = nfs_permission, | |
118 | .getattr = nfs_getattr, | |
119 | .setattr = nfs_setattr, | |
6b3b5496 BF |
120 | .getxattr = nfs4_getxattr, |
121 | .setxattr = nfs4_setxattr, | |
122 | .listxattr = nfs4_listxattr, | |
1da177e4 LT |
123 | }; |
124 | ||
125 | #endif /* CONFIG_NFS_V4 */ | |
126 | ||
127 | /* | |
128 | * Open file | |
129 | */ | |
130 | static int | |
131 | nfs_opendir(struct inode *inode, struct file *filp) | |
132 | { | |
7451c4f0 | 133 | int res; |
1da177e4 | 134 | |
1e7cb3dc CL |
135 | dfprintk(VFS, "NFS: opendir(%s/%ld)\n", |
136 | inode->i_sb->s_id, inode->i_ino); | |
137 | ||
1da177e4 LT |
138 | lock_kernel(); |
139 | /* Call generic open code in order to cache credentials */ | |
7451c4f0 | 140 | res = nfs_open(inode, filp); |
1da177e4 LT |
141 | unlock_kernel(); |
142 | return res; | |
143 | } | |
144 | ||
0dbb4c67 | 145 | typedef __be32 * (*decode_dirent_t)(__be32 *, struct nfs_entry *, int); |
1da177e4 LT |
146 | typedef struct { |
147 | struct file *file; | |
148 | struct page *page; | |
149 | unsigned long page_index; | |
0dbb4c67 | 150 | __be32 *ptr; |
f0dd2136 TM |
151 | u64 *dir_cookie; |
152 | loff_t current_index; | |
1da177e4 LT |
153 | struct nfs_entry *entry; |
154 | decode_dirent_t decode; | |
155 | int plus; | |
156 | int error; | |
1f4eab7e NB |
157 | unsigned long timestamp; |
158 | int timestamp_valid; | |
1da177e4 LT |
159 | } nfs_readdir_descriptor_t; |
160 | ||
161 | /* Now we cache directories properly, by stuffing the dirent | |
162 | * data directly in the page cache. | |
163 | * | |
164 | * Inode invalidation due to refresh etc. takes care of | |
165 | * _everything_, no sloppy entry flushing logic, no extraneous | |
166 | * copying, network direct to page cache, the way it was meant | |
167 | * to be. | |
168 | * | |
169 | * NOTE: Dirent information verification is done always by the | |
170 | * page-in of the RPC reply, nowhere else, this simplies | |
171 | * things substantially. | |
172 | */ | |
173 | static | |
174 | int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page *page) | |
175 | { | |
176 | struct file *file = desc->file; | |
01cce933 | 177 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
178 | struct rpc_cred *cred = nfs_file_cred(file); |
179 | unsigned long timestamp; | |
180 | int error; | |
181 | ||
1e7cb3dc CL |
182 | dfprintk(DIRCACHE, "NFS: %s: reading cookie %Lu into page %lu\n", |
183 | __FUNCTION__, (long long)desc->entry->cookie, | |
184 | page->index); | |
1da177e4 LT |
185 | |
186 | again: | |
187 | timestamp = jiffies; | |
01cce933 | 188 | error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, desc->entry->cookie, page, |
1da177e4 LT |
189 | NFS_SERVER(inode)->dtsize, desc->plus); |
190 | if (error < 0) { | |
191 | /* We requested READDIRPLUS, but the server doesn't grok it */ | |
192 | if (error == -ENOTSUPP && desc->plus) { | |
193 | NFS_SERVER(inode)->caps &= ~NFS_CAP_READDIRPLUS; | |
412d582e | 194 | clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode)); |
1da177e4 LT |
195 | desc->plus = 0; |
196 | goto again; | |
197 | } | |
198 | goto error; | |
199 | } | |
1f4eab7e NB |
200 | desc->timestamp = timestamp; |
201 | desc->timestamp_valid = 1; | |
1da177e4 | 202 | SetPageUptodate(page); |
dc59250c | 203 | spin_lock(&inode->i_lock); |
55296809 | 204 | NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME; |
dc59250c | 205 | spin_unlock(&inode->i_lock); |
1da177e4 LT |
206 | /* Ensure consistent page alignment of the data. |
207 | * Note: assumes we have exclusive access to this mapping either | |
1b1dcc1b | 208 | * through inode->i_mutex or some other mechanism. |
1da177e4 | 209 | */ |
cd9ae2b6 TM |
210 | if (page->index == 0 && invalidate_inode_pages2_range(inode->i_mapping, PAGE_CACHE_SIZE, -1) < 0) { |
211 | /* Should never happen */ | |
212 | nfs_zap_mapping(inode, inode->i_mapping); | |
213 | } | |
1da177e4 LT |
214 | unlock_page(page); |
215 | return 0; | |
216 | error: | |
217 | SetPageError(page); | |
218 | unlock_page(page); | |
219 | nfs_zap_caches(inode); | |
220 | desc->error = error; | |
221 | return -EIO; | |
222 | } | |
223 | ||
224 | static inline | |
225 | int dir_decode(nfs_readdir_descriptor_t *desc) | |
226 | { | |
0dbb4c67 | 227 | __be32 *p = desc->ptr; |
1da177e4 LT |
228 | p = desc->decode(p, desc->entry, desc->plus); |
229 | if (IS_ERR(p)) | |
230 | return PTR_ERR(p); | |
231 | desc->ptr = p; | |
1f4eab7e NB |
232 | if (desc->timestamp_valid) |
233 | desc->entry->fattr->time_start = desc->timestamp; | |
234 | else | |
235 | desc->entry->fattr->valid &= ~NFS_ATTR_FATTR; | |
1da177e4 LT |
236 | return 0; |
237 | } | |
238 | ||
239 | static inline | |
240 | void dir_page_release(nfs_readdir_descriptor_t *desc) | |
241 | { | |
242 | kunmap(desc->page); | |
243 | page_cache_release(desc->page); | |
244 | desc->page = NULL; | |
245 | desc->ptr = NULL; | |
246 | } | |
247 | ||
248 | /* | |
249 | * Given a pointer to a buffer that has already been filled by a call | |
f0dd2136 | 250 | * to readdir, find the next entry with cookie '*desc->dir_cookie'. |
1da177e4 LT |
251 | * |
252 | * If the end of the buffer has been reached, return -EAGAIN, if not, | |
253 | * return the offset within the buffer of the next entry to be | |
254 | * read. | |
255 | */ | |
256 | static inline | |
00a92642 | 257 | int find_dirent(nfs_readdir_descriptor_t *desc) |
1da177e4 LT |
258 | { |
259 | struct nfs_entry *entry = desc->entry; | |
260 | int loop_count = 0, | |
261 | status; | |
262 | ||
263 | while((status = dir_decode(desc)) == 0) { | |
1e7cb3dc CL |
264 | dfprintk(DIRCACHE, "NFS: %s: examining cookie %Lu\n", |
265 | __FUNCTION__, (unsigned long long)entry->cookie); | |
f0dd2136 | 266 | if (entry->prev_cookie == *desc->dir_cookie) |
1da177e4 LT |
267 | break; |
268 | if (loop_count++ > 200) { | |
269 | loop_count = 0; | |
270 | schedule(); | |
271 | } | |
272 | } | |
1da177e4 LT |
273 | return status; |
274 | } | |
275 | ||
276 | /* | |
00a92642 | 277 | * Given a pointer to a buffer that has already been filled by a call |
f0dd2136 | 278 | * to readdir, find the entry at offset 'desc->file->f_pos'. |
00a92642 OG |
279 | * |
280 | * If the end of the buffer has been reached, return -EAGAIN, if not, | |
281 | * return the offset within the buffer of the next entry to be | |
282 | * read. | |
283 | */ | |
284 | static inline | |
285 | int find_dirent_index(nfs_readdir_descriptor_t *desc) | |
286 | { | |
287 | struct nfs_entry *entry = desc->entry; | |
288 | int loop_count = 0, | |
289 | status; | |
290 | ||
291 | for(;;) { | |
292 | status = dir_decode(desc); | |
293 | if (status) | |
294 | break; | |
295 | ||
1e7cb3dc CL |
296 | dfprintk(DIRCACHE, "NFS: found cookie %Lu at index %Ld\n", |
297 | (unsigned long long)entry->cookie, desc->current_index); | |
00a92642 | 298 | |
f0dd2136 TM |
299 | if (desc->file->f_pos == desc->current_index) { |
300 | *desc->dir_cookie = entry->cookie; | |
00a92642 OG |
301 | break; |
302 | } | |
303 | desc->current_index++; | |
304 | if (loop_count++ > 200) { | |
305 | loop_count = 0; | |
306 | schedule(); | |
307 | } | |
308 | } | |
00a92642 OG |
309 | return status; |
310 | } | |
311 | ||
312 | /* | |
313 | * Find the given page, and call find_dirent() or find_dirent_index in | |
314 | * order to try to return the next entry. | |
1da177e4 LT |
315 | */ |
316 | static inline | |
317 | int find_dirent_page(nfs_readdir_descriptor_t *desc) | |
318 | { | |
01cce933 | 319 | struct inode *inode = desc->file->f_path.dentry->d_inode; |
1da177e4 LT |
320 | struct page *page; |
321 | int status; | |
322 | ||
1e7cb3dc CL |
323 | dfprintk(DIRCACHE, "NFS: %s: searching page %ld for target %Lu\n", |
324 | __FUNCTION__, desc->page_index, | |
325 | (long long) *desc->dir_cookie); | |
1da177e4 | 326 | |
1f4eab7e NB |
327 | /* If we find the page in the page_cache, we cannot be sure |
328 | * how fresh the data is, so we will ignore readdir_plus attributes. | |
329 | */ | |
330 | desc->timestamp_valid = 0; | |
1da177e4 LT |
331 | page = read_cache_page(inode->i_mapping, desc->page_index, |
332 | (filler_t *)nfs_readdir_filler, desc); | |
333 | if (IS_ERR(page)) { | |
334 | status = PTR_ERR(page); | |
335 | goto out; | |
336 | } | |
1da177e4 LT |
337 | |
338 | /* NOTE: Someone else may have changed the READDIRPLUS flag */ | |
339 | desc->page = page; | |
340 | desc->ptr = kmap(page); /* matching kunmap in nfs_do_filldir */ | |
f0dd2136 | 341 | if (*desc->dir_cookie != 0) |
00a92642 OG |
342 | status = find_dirent(desc); |
343 | else | |
344 | status = find_dirent_index(desc); | |
1da177e4 LT |
345 | if (status < 0) |
346 | dir_page_release(desc); | |
347 | out: | |
1e7cb3dc | 348 | dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, status); |
1da177e4 | 349 | return status; |
1da177e4 LT |
350 | } |
351 | ||
352 | /* | |
353 | * Recurse through the page cache pages, and return a | |
354 | * filled nfs_entry structure of the next directory entry if possible. | |
355 | * | |
f0dd2136 TM |
356 | * The target for the search is '*desc->dir_cookie' if non-0, |
357 | * 'desc->file->f_pos' otherwise | |
1da177e4 LT |
358 | */ |
359 | static inline | |
360 | int readdir_search_pagecache(nfs_readdir_descriptor_t *desc) | |
361 | { | |
362 | int loop_count = 0; | |
363 | int res; | |
364 | ||
00a92642 | 365 | /* Always search-by-index from the beginning of the cache */ |
f0dd2136 | 366 | if (*desc->dir_cookie == 0) { |
1e7cb3dc CL |
367 | dfprintk(DIRCACHE, "NFS: readdir_search_pagecache() searching for offset %Ld\n", |
368 | (long long)desc->file->f_pos); | |
00a92642 OG |
369 | desc->page_index = 0; |
370 | desc->entry->cookie = desc->entry->prev_cookie = 0; | |
371 | desc->entry->eof = 0; | |
372 | desc->current_index = 0; | |
f0dd2136 | 373 | } else |
1e7cb3dc CL |
374 | dfprintk(DIRCACHE, "NFS: readdir_search_pagecache() searching for cookie %Lu\n", |
375 | (unsigned long long)*desc->dir_cookie); | |
00a92642 | 376 | |
1da177e4 LT |
377 | for (;;) { |
378 | res = find_dirent_page(desc); | |
379 | if (res != -EAGAIN) | |
380 | break; | |
381 | /* Align to beginning of next page */ | |
382 | desc->page_index ++; | |
383 | if (loop_count++ > 200) { | |
384 | loop_count = 0; | |
385 | schedule(); | |
386 | } | |
387 | } | |
1e7cb3dc CL |
388 | |
389 | dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, res); | |
1da177e4 LT |
390 | return res; |
391 | } | |
392 | ||
393 | static inline unsigned int dt_type(struct inode *inode) | |
394 | { | |
395 | return (inode->i_mode >> 12) & 15; | |
396 | } | |
397 | ||
398 | static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc); | |
399 | ||
400 | /* | |
401 | * Once we've found the start of the dirent within a page: fill 'er up... | |
402 | */ | |
403 | static | |
404 | int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent, | |
405 | filldir_t filldir) | |
406 | { | |
407 | struct file *file = desc->file; | |
408 | struct nfs_entry *entry = desc->entry; | |
409 | struct dentry *dentry = NULL; | |
4e769b93 | 410 | u64 fileid; |
1da177e4 LT |
411 | int loop_count = 0, |
412 | res; | |
413 | ||
1e7cb3dc CL |
414 | dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling starting @ cookie %Lu\n", |
415 | (unsigned long long)entry->cookie); | |
1da177e4 LT |
416 | |
417 | for(;;) { | |
418 | unsigned d_type = DT_UNKNOWN; | |
419 | /* Note: entry->prev_cookie contains the cookie for | |
420 | * retrieving the current dirent on the server */ | |
4e769b93 | 421 | fileid = entry->ino; |
1da177e4 LT |
422 | |
423 | /* Get a dentry if we have one */ | |
424 | if (dentry != NULL) | |
425 | dput(dentry); | |
426 | dentry = nfs_readdir_lookup(desc); | |
427 | ||
428 | /* Use readdirplus info */ | |
429 | if (dentry != NULL && dentry->d_inode != NULL) { | |
430 | d_type = dt_type(dentry->d_inode); | |
4e769b93 | 431 | fileid = NFS_FILEID(dentry->d_inode); |
1da177e4 LT |
432 | } |
433 | ||
434 | res = filldir(dirent, entry->name, entry->len, | |
00a92642 | 435 | file->f_pos, fileid, d_type); |
1da177e4 LT |
436 | if (res < 0) |
437 | break; | |
00a92642 | 438 | file->f_pos++; |
f0dd2136 | 439 | *desc->dir_cookie = entry->cookie; |
1da177e4 LT |
440 | if (dir_decode(desc) != 0) { |
441 | desc->page_index ++; | |
442 | break; | |
443 | } | |
444 | if (loop_count++ > 200) { | |
445 | loop_count = 0; | |
446 | schedule(); | |
447 | } | |
448 | } | |
449 | dir_page_release(desc); | |
450 | if (dentry != NULL) | |
451 | dput(dentry); | |
1e7cb3dc CL |
452 | dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n", |
453 | (unsigned long long)*desc->dir_cookie, res); | |
1da177e4 LT |
454 | return res; |
455 | } | |
456 | ||
457 | /* | |
458 | * If we cannot find a cookie in our cache, we suspect that this is | |
459 | * because it points to a deleted file, so we ask the server to return | |
460 | * whatever it thinks is the next entry. We then feed this to filldir. | |
461 | * If all goes well, we should then be able to find our way round the | |
462 | * cache on the next call to readdir_search_pagecache(); | |
463 | * | |
464 | * NOTE: we cannot add the anonymous page to the pagecache because | |
465 | * the data it contains might not be page aligned. Besides, | |
466 | * we should already have a complete representation of the | |
467 | * directory in the page cache by the time we get here. | |
468 | */ | |
469 | static inline | |
470 | int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent, | |
471 | filldir_t filldir) | |
472 | { | |
473 | struct file *file = desc->file; | |
01cce933 | 474 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
475 | struct rpc_cred *cred = nfs_file_cred(file); |
476 | struct page *page = NULL; | |
477 | int status; | |
1f4eab7e | 478 | unsigned long timestamp; |
1da177e4 | 479 | |
1e7cb3dc CL |
480 | dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %Lu\n", |
481 | (unsigned long long)*desc->dir_cookie); | |
1da177e4 LT |
482 | |
483 | page = alloc_page(GFP_HIGHUSER); | |
484 | if (!page) { | |
485 | status = -ENOMEM; | |
486 | goto out; | |
487 | } | |
1f4eab7e | 488 | timestamp = jiffies; |
01cce933 | 489 | desc->error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, *desc->dir_cookie, |
1da177e4 LT |
490 | page, |
491 | NFS_SERVER(inode)->dtsize, | |
492 | desc->plus); | |
dc59250c | 493 | spin_lock(&inode->i_lock); |
55296809 | 494 | NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME; |
dc59250c | 495 | spin_unlock(&inode->i_lock); |
1da177e4 LT |
496 | desc->page = page; |
497 | desc->ptr = kmap(page); /* matching kunmap in nfs_do_filldir */ | |
498 | if (desc->error >= 0) { | |
1f4eab7e NB |
499 | desc->timestamp = timestamp; |
500 | desc->timestamp_valid = 1; | |
1da177e4 | 501 | if ((status = dir_decode(desc)) == 0) |
f0dd2136 | 502 | desc->entry->prev_cookie = *desc->dir_cookie; |
1da177e4 LT |
503 | } else |
504 | status = -EIO; | |
505 | if (status < 0) | |
506 | goto out_release; | |
507 | ||
508 | status = nfs_do_filldir(desc, dirent, filldir); | |
509 | ||
510 | /* Reset read descriptor so it searches the page cache from | |
511 | * the start upon the next call to readdir_search_pagecache() */ | |
512 | desc->page_index = 0; | |
513 | desc->entry->cookie = desc->entry->prev_cookie = 0; | |
514 | desc->entry->eof = 0; | |
515 | out: | |
1e7cb3dc CL |
516 | dfprintk(DIRCACHE, "NFS: %s: returns %d\n", |
517 | __FUNCTION__, status); | |
1da177e4 LT |
518 | return status; |
519 | out_release: | |
520 | dir_page_release(desc); | |
521 | goto out; | |
522 | } | |
523 | ||
00a92642 OG |
524 | /* The file offset position represents the dirent entry number. A |
525 | last cookie cache takes care of the common case of reading the | |
526 | whole directory. | |
1da177e4 LT |
527 | */ |
528 | static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir) | |
529 | { | |
01cce933 | 530 | struct dentry *dentry = filp->f_path.dentry; |
1da177e4 LT |
531 | struct inode *inode = dentry->d_inode; |
532 | nfs_readdir_descriptor_t my_desc, | |
533 | *desc = &my_desc; | |
534 | struct nfs_entry my_entry; | |
535 | struct nfs_fh fh; | |
536 | struct nfs_fattr fattr; | |
537 | long res; | |
538 | ||
1e7cb3dc CL |
539 | dfprintk(VFS, "NFS: readdir(%s/%s) starting at cookie %Lu\n", |
540 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
541 | (long long)filp->f_pos); | |
91d5b470 CL |
542 | nfs_inc_stats(inode, NFSIOS_VFSGETDENTS); |
543 | ||
1da177e4 LT |
544 | lock_kernel(); |
545 | ||
717d44e8 | 546 | res = nfs_revalidate_mapping_nolock(inode, filp->f_mapping); |
1da177e4 LT |
547 | if (res < 0) { |
548 | unlock_kernel(); | |
549 | return res; | |
550 | } | |
551 | ||
552 | /* | |
00a92642 | 553 | * filp->f_pos points to the dirent entry number. |
f0dd2136 | 554 | * *desc->dir_cookie has the cookie for the next entry. We have |
00a92642 OG |
555 | * to either find the entry with the appropriate number or |
556 | * revalidate the cookie. | |
1da177e4 LT |
557 | */ |
558 | memset(desc, 0, sizeof(*desc)); | |
559 | ||
560 | desc->file = filp; | |
cd3758e3 | 561 | desc->dir_cookie = &nfs_file_open_context(filp)->dir_cookie; |
1da177e4 LT |
562 | desc->decode = NFS_PROTO(inode)->decode_dirent; |
563 | desc->plus = NFS_USE_READDIRPLUS(inode); | |
564 | ||
565 | my_entry.cookie = my_entry.prev_cookie = 0; | |
566 | my_entry.eof = 0; | |
567 | my_entry.fh = &fh; | |
568 | my_entry.fattr = &fattr; | |
0e574af1 | 569 | nfs_fattr_init(&fattr); |
1da177e4 LT |
570 | desc->entry = &my_entry; |
571 | ||
572 | while(!desc->entry->eof) { | |
573 | res = readdir_search_pagecache(desc); | |
00a92642 | 574 | |
1da177e4 LT |
575 | if (res == -EBADCOOKIE) { |
576 | /* This means either end of directory */ | |
f0dd2136 | 577 | if (*desc->dir_cookie && desc->entry->cookie != *desc->dir_cookie) { |
1da177e4 LT |
578 | /* Or that the server has 'lost' a cookie */ |
579 | res = uncached_readdir(desc, dirent, filldir); | |
580 | if (res >= 0) | |
581 | continue; | |
582 | } | |
583 | res = 0; | |
584 | break; | |
585 | } | |
586 | if (res == -ETOOSMALL && desc->plus) { | |
412d582e | 587 | clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode)); |
1da177e4 LT |
588 | nfs_zap_caches(inode); |
589 | desc->plus = 0; | |
590 | desc->entry->eof = 0; | |
591 | continue; | |
592 | } | |
593 | if (res < 0) | |
594 | break; | |
595 | ||
596 | res = nfs_do_filldir(desc, dirent, filldir); | |
597 | if (res < 0) { | |
598 | res = 0; | |
599 | break; | |
600 | } | |
601 | } | |
602 | unlock_kernel(); | |
1e7cb3dc CL |
603 | if (res > 0) |
604 | res = 0; | |
605 | dfprintk(VFS, "NFS: readdir(%s/%s) returns %ld\n", | |
606 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
607 | res); | |
608 | return res; | |
1da177e4 LT |
609 | } |
610 | ||
10afec90 | 611 | static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin) |
f0dd2136 | 612 | { |
01cce933 | 613 | mutex_lock(&filp->f_path.dentry->d_inode->i_mutex); |
f0dd2136 TM |
614 | switch (origin) { |
615 | case 1: | |
616 | offset += filp->f_pos; | |
617 | case 0: | |
618 | if (offset >= 0) | |
619 | break; | |
620 | default: | |
621 | offset = -EINVAL; | |
622 | goto out; | |
623 | } | |
624 | if (offset != filp->f_pos) { | |
625 | filp->f_pos = offset; | |
cd3758e3 | 626 | nfs_file_open_context(filp)->dir_cookie = 0; |
f0dd2136 TM |
627 | } |
628 | out: | |
01cce933 | 629 | mutex_unlock(&filp->f_path.dentry->d_inode->i_mutex); |
f0dd2136 TM |
630 | return offset; |
631 | } | |
632 | ||
1da177e4 LT |
633 | /* |
634 | * All directory operations under NFS are synchronous, so fsync() | |
635 | * is a dummy operation. | |
636 | */ | |
10afec90 | 637 | static int nfs_fsync_dir(struct file *filp, struct dentry *dentry, int datasync) |
1da177e4 | 638 | { |
1e7cb3dc CL |
639 | dfprintk(VFS, "NFS: fsync_dir(%s/%s) datasync %d\n", |
640 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
641 | datasync); | |
642 | ||
1da177e4 LT |
643 | return 0; |
644 | } | |
645 | ||
646 | /* | |
647 | * A check for whether or not the parent directory has changed. | |
648 | * In the case it has, we assume that the dentries are untrustworthy | |
649 | * and may need to be looked up again. | |
650 | */ | |
c79ba787 | 651 | static int nfs_check_verifier(struct inode *dir, struct dentry *dentry) |
1da177e4 LT |
652 | { |
653 | if (IS_ROOT(dentry)) | |
654 | return 1; | |
6ecc5e8f TM |
655 | if (dentry->d_time == NFS_I(dir)->cache_change_attribute) |
656 | return 1; | |
657 | return 0; | |
1da177e4 LT |
658 | } |
659 | ||
660 | static inline void nfs_set_verifier(struct dentry * dentry, unsigned long verf) | |
661 | { | |
3062c532 | 662 | dentry->d_time = verf; |
1da177e4 LT |
663 | } |
664 | ||
1d6757fb TM |
665 | /* |
666 | * Return the intent data that applies to this particular path component | |
667 | * | |
668 | * Note that the current set of intents only apply to the very last | |
669 | * component of the path. | |
670 | * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT. | |
671 | */ | |
672 | static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd, unsigned int mask) | |
673 | { | |
674 | if (nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT)) | |
675 | return 0; | |
676 | return nd->flags & mask; | |
677 | } | |
678 | ||
679 | /* | |
680 | * Inode and filehandle revalidation for lookups. | |
681 | * | |
682 | * We force revalidation in the cases where the VFS sets LOOKUP_REVAL, | |
683 | * or if the intent information indicates that we're about to open this | |
684 | * particular file and the "nocto" mount flag is not set. | |
685 | * | |
686 | */ | |
1da177e4 LT |
687 | static inline |
688 | int nfs_lookup_verify_inode(struct inode *inode, struct nameidata *nd) | |
689 | { | |
690 | struct nfs_server *server = NFS_SERVER(inode); | |
691 | ||
692 | if (nd != NULL) { | |
1da177e4 | 693 | /* VFS wants an on-the-wire revalidation */ |
1d6757fb | 694 | if (nd->flags & LOOKUP_REVAL) |
1da177e4 LT |
695 | goto out_force; |
696 | /* This is an open(2) */ | |
1d6757fb | 697 | if (nfs_lookup_check_intent(nd, LOOKUP_OPEN) != 0 && |
4e0641a7 TM |
698 | !(server->flags & NFS_MOUNT_NOCTO) && |
699 | (S_ISREG(inode->i_mode) || | |
700 | S_ISDIR(inode->i_mode))) | |
1da177e4 LT |
701 | goto out_force; |
702 | } | |
703 | return nfs_revalidate_inode(server, inode); | |
704 | out_force: | |
705 | return __nfs_revalidate_inode(server, inode); | |
706 | } | |
707 | ||
708 | /* | |
709 | * We judge how long we want to trust negative | |
710 | * dentries by looking at the parent inode mtime. | |
711 | * | |
712 | * If parent mtime has changed, we revalidate, else we wait for a | |
713 | * period corresponding to the parent's attribute cache timeout value. | |
714 | */ | |
715 | static inline | |
716 | int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry, | |
717 | struct nameidata *nd) | |
718 | { | |
1da177e4 | 719 | /* Don't revalidate a negative dentry if we're creating a new file */ |
1d6757fb | 720 | if (nd != NULL && nfs_lookup_check_intent(nd, LOOKUP_CREATE) != 0) |
1da177e4 LT |
721 | return 0; |
722 | return !nfs_check_verifier(dir, dentry); | |
723 | } | |
724 | ||
725 | /* | |
726 | * This is called every time the dcache has a lookup hit, | |
727 | * and we should check whether we can really trust that | |
728 | * lookup. | |
729 | * | |
730 | * NOTE! The hit can be a negative hit too, don't assume | |
731 | * we have an inode! | |
732 | * | |
733 | * If the parent directory is seen to have changed, we throw out the | |
734 | * cached dentry and do a new lookup. | |
735 | */ | |
736 | static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd) | |
737 | { | |
738 | struct inode *dir; | |
739 | struct inode *inode; | |
740 | struct dentry *parent; | |
741 | int error; | |
742 | struct nfs_fh fhandle; | |
743 | struct nfs_fattr fattr; | |
744 | unsigned long verifier; | |
745 | ||
746 | parent = dget_parent(dentry); | |
747 | lock_kernel(); | |
748 | dir = parent->d_inode; | |
91d5b470 | 749 | nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE); |
1da177e4 LT |
750 | inode = dentry->d_inode; |
751 | ||
e70c4908 TM |
752 | /* Revalidate parent directory attribute cache */ |
753 | if (nfs_revalidate_inode(NFS_SERVER(dir), dir) < 0) | |
754 | goto out_zap_parent; | |
755 | ||
1da177e4 LT |
756 | if (!inode) { |
757 | if (nfs_neg_need_reval(dir, dentry, nd)) | |
758 | goto out_bad; | |
759 | goto out_valid; | |
760 | } | |
761 | ||
762 | if (is_bad_inode(inode)) { | |
1e7cb3dc CL |
763 | dfprintk(LOOKUPCACHE, "%s: %s/%s has dud inode\n", |
764 | __FUNCTION__, dentry->d_parent->d_name.name, | |
765 | dentry->d_name.name); | |
1da177e4 LT |
766 | goto out_bad; |
767 | } | |
768 | ||
1da177e4 LT |
769 | /* Force a full look up iff the parent directory has changed */ |
770 | if (nfs_check_verifier(dir, dentry)) { | |
771 | if (nfs_lookup_verify_inode(inode, nd)) | |
772 | goto out_zap_parent; | |
773 | goto out_valid; | |
774 | } | |
775 | ||
776 | if (NFS_STALE(inode)) | |
777 | goto out_bad; | |
778 | ||
779 | verifier = nfs_save_change_attribute(dir); | |
780 | error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, &fhandle, &fattr); | |
781 | if (error) | |
782 | goto out_bad; | |
783 | if (nfs_compare_fh(NFS_FH(inode), &fhandle)) | |
784 | goto out_bad; | |
785 | if ((error = nfs_refresh_inode(inode, &fattr)) != 0) | |
786 | goto out_bad; | |
787 | ||
8fb559f8 | 788 | nfs_set_verifier(dentry, verifier); |
1da177e4 LT |
789 | out_valid: |
790 | unlock_kernel(); | |
791 | dput(parent); | |
1e7cb3dc CL |
792 | dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is valid\n", |
793 | __FUNCTION__, dentry->d_parent->d_name.name, | |
794 | dentry->d_name.name); | |
1da177e4 LT |
795 | return 1; |
796 | out_zap_parent: | |
797 | nfs_zap_caches(dir); | |
798 | out_bad: | |
799 | NFS_CACHEINV(dir); | |
800 | if (inode && S_ISDIR(inode->i_mode)) { | |
801 | /* Purge readdir caches. */ | |
802 | nfs_zap_caches(inode); | |
803 | /* If we have submounts, don't unhash ! */ | |
804 | if (have_submounts(dentry)) | |
805 | goto out_valid; | |
806 | shrink_dcache_parent(dentry); | |
807 | } | |
808 | d_drop(dentry); | |
809 | unlock_kernel(); | |
810 | dput(parent); | |
1e7cb3dc CL |
811 | dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is invalid\n", |
812 | __FUNCTION__, dentry->d_parent->d_name.name, | |
813 | dentry->d_name.name); | |
1da177e4 LT |
814 | return 0; |
815 | } | |
816 | ||
817 | /* | |
818 | * This is called from dput() when d_count is going to 0. | |
819 | */ | |
820 | static int nfs_dentry_delete(struct dentry *dentry) | |
821 | { | |
822 | dfprintk(VFS, "NFS: dentry_delete(%s/%s, %x)\n", | |
823 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
824 | dentry->d_flags); | |
825 | ||
826 | if (dentry->d_flags & DCACHE_NFSFS_RENAMED) { | |
827 | /* Unhash it, so that ->d_iput() would be called */ | |
828 | return 1; | |
829 | } | |
830 | if (!(dentry->d_sb->s_flags & MS_ACTIVE)) { | |
831 | /* Unhash it, so that ancestors of killed async unlink | |
832 | * files will be cleaned up during umount */ | |
833 | return 1; | |
834 | } | |
835 | return 0; | |
836 | ||
837 | } | |
838 | ||
839 | /* | |
840 | * Called when the dentry loses inode. | |
841 | * We use it to clean up silly-renamed files. | |
842 | */ | |
843 | static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode) | |
844 | { | |
cae7a073 | 845 | nfs_inode_return_delegation(inode); |
83672d39 NB |
846 | if (S_ISDIR(inode->i_mode)) |
847 | /* drop any readdir cache as it could easily be old */ | |
848 | NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA; | |
849 | ||
1da177e4 LT |
850 | if (dentry->d_flags & DCACHE_NFSFS_RENAMED) { |
851 | lock_kernel(); | |
9a53c3a7 | 852 | drop_nlink(inode); |
e4eff1a6 | 853 | nfs_complete_unlink(dentry, inode); |
1da177e4 LT |
854 | unlock_kernel(); |
855 | } | |
1da177e4 LT |
856 | iput(inode); |
857 | } | |
858 | ||
859 | struct dentry_operations nfs_dentry_operations = { | |
860 | .d_revalidate = nfs_lookup_revalidate, | |
861 | .d_delete = nfs_dentry_delete, | |
862 | .d_iput = nfs_dentry_iput, | |
863 | }; | |
864 | ||
1d6757fb TM |
865 | /* |
866 | * Use intent information to check whether or not we're going to do | |
867 | * an O_EXCL create using this path component. | |
868 | */ | |
1da177e4 LT |
869 | static inline |
870 | int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd) | |
871 | { | |
872 | if (NFS_PROTO(dir)->version == 2) | |
873 | return 0; | |
1d6757fb | 874 | if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_CREATE) == 0) |
1da177e4 LT |
875 | return 0; |
876 | return (nd->intent.open.flags & O_EXCL) != 0; | |
877 | } | |
878 | ||
a0356862 | 879 | static inline int nfs_reval_fsid(struct inode *dir, const struct nfs_fattr *fattr) |
55a97593 TM |
880 | { |
881 | struct nfs_server *server = NFS_SERVER(dir); | |
882 | ||
883 | if (!nfs_fsid_equal(&server->fsid, &fattr->fsid)) | |
a0356862 TM |
884 | /* Revalidate fsid using the parent directory */ |
885 | return __nfs_revalidate_inode(server, dir); | |
55a97593 TM |
886 | return 0; |
887 | } | |
888 | ||
1da177e4 LT |
889 | static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) |
890 | { | |
891 | struct dentry *res; | |
892 | struct inode *inode = NULL; | |
893 | int error; | |
894 | struct nfs_fh fhandle; | |
895 | struct nfs_fattr fattr; | |
896 | ||
897 | dfprintk(VFS, "NFS: lookup(%s/%s)\n", | |
898 | dentry->d_parent->d_name.name, dentry->d_name.name); | |
91d5b470 | 899 | nfs_inc_stats(dir, NFSIOS_VFSLOOKUP); |
1da177e4 LT |
900 | |
901 | res = ERR_PTR(-ENAMETOOLONG); | |
902 | if (dentry->d_name.len > NFS_SERVER(dir)->namelen) | |
903 | goto out; | |
904 | ||
905 | res = ERR_PTR(-ENOMEM); | |
906 | dentry->d_op = NFS_PROTO(dir)->dentry_ops; | |
907 | ||
908 | lock_kernel(); | |
1da177e4 | 909 | |
fd684071 TM |
910 | /* |
911 | * If we're doing an exclusive create, optimize away the lookup | |
912 | * but don't hash the dentry. | |
913 | */ | |
914 | if (nfs_is_exclusive_create(dir, nd)) { | |
915 | d_instantiate(dentry, NULL); | |
916 | res = NULL; | |
917 | goto out_unlock; | |
918 | } | |
1da177e4 LT |
919 | |
920 | error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, &fhandle, &fattr); | |
921 | if (error == -ENOENT) | |
922 | goto no_entry; | |
923 | if (error < 0) { | |
924 | res = ERR_PTR(error); | |
925 | goto out_unlock; | |
926 | } | |
a0356862 | 927 | error = nfs_reval_fsid(dir, &fattr); |
55a97593 TM |
928 | if (error < 0) { |
929 | res = ERR_PTR(error); | |
930 | goto out_unlock; | |
931 | } | |
1da177e4 | 932 | inode = nfs_fhget(dentry->d_sb, &fhandle, &fattr); |
03f28e3a TM |
933 | res = (struct dentry *)inode; |
934 | if (IS_ERR(res)) | |
1da177e4 | 935 | goto out_unlock; |
54ceac45 | 936 | |
1da177e4 | 937 | no_entry: |
54ceac45 | 938 | res = d_materialise_unique(dentry, inode); |
9eaef27b | 939 | if (res != NULL) { |
fc22617e | 940 | struct dentry *parent; |
9eaef27b TM |
941 | if (IS_ERR(res)) |
942 | goto out_unlock; | |
fc22617e TM |
943 | /* Was a directory renamed! */ |
944 | parent = dget_parent(res); | |
945 | if (!IS_ROOT(parent)) | |
946 | nfs_mark_for_revalidate(parent->d_inode); | |
947 | dput(parent); | |
1da177e4 | 948 | dentry = res; |
9eaef27b | 949 | } |
1da177e4 LT |
950 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); |
951 | out_unlock: | |
952 | unlock_kernel(); | |
953 | out: | |
954 | return res; | |
955 | } | |
956 | ||
957 | #ifdef CONFIG_NFS_V4 | |
958 | static int nfs_open_revalidate(struct dentry *, struct nameidata *); | |
959 | ||
960 | struct dentry_operations nfs4_dentry_operations = { | |
961 | .d_revalidate = nfs_open_revalidate, | |
962 | .d_delete = nfs_dentry_delete, | |
963 | .d_iput = nfs_dentry_iput, | |
964 | }; | |
965 | ||
1d6757fb TM |
966 | /* |
967 | * Use intent information to determine whether we need to substitute | |
968 | * the NFSv4-style stateful OPEN for the LOOKUP call | |
969 | */ | |
1da177e4 LT |
970 | static int is_atomic_open(struct inode *dir, struct nameidata *nd) |
971 | { | |
1d6757fb | 972 | if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_OPEN) == 0) |
1da177e4 LT |
973 | return 0; |
974 | /* NFS does not (yet) have a stateful open for directories */ | |
975 | if (nd->flags & LOOKUP_DIRECTORY) | |
976 | return 0; | |
977 | /* Are we trying to write to a read only partition? */ | |
978 | if (IS_RDONLY(dir) && (nd->intent.open.flags & (O_CREAT|O_TRUNC|FMODE_WRITE))) | |
979 | return 0; | |
980 | return 1; | |
981 | } | |
982 | ||
983 | static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) | |
984 | { | |
985 | struct dentry *res = NULL; | |
1da177e4 LT |
986 | int error; |
987 | ||
1e7cb3dc CL |
988 | dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n", |
989 | dir->i_sb->s_id, dir->i_ino, dentry->d_name.name); | |
990 | ||
1da177e4 LT |
991 | /* Check that we are indeed trying to open this file */ |
992 | if (!is_atomic_open(dir, nd)) | |
993 | goto no_open; | |
994 | ||
995 | if (dentry->d_name.len > NFS_SERVER(dir)->namelen) { | |
996 | res = ERR_PTR(-ENAMETOOLONG); | |
997 | goto out; | |
998 | } | |
999 | dentry->d_op = NFS_PROTO(dir)->dentry_ops; | |
1000 | ||
1001 | /* Let vfs_create() deal with O_EXCL */ | |
02a913a7 TM |
1002 | if (nd->intent.open.flags & O_EXCL) { |
1003 | d_add(dentry, NULL); | |
1004 | goto out; | |
1005 | } | |
1da177e4 LT |
1006 | |
1007 | /* Open the file on the server */ | |
1008 | lock_kernel(); | |
1009 | /* Revalidate parent directory attribute cache */ | |
1010 | error = nfs_revalidate_inode(NFS_SERVER(dir), dir); | |
1011 | if (error < 0) { | |
1012 | res = ERR_PTR(error); | |
01c314a0 | 1013 | unlock_kernel(); |
1da177e4 LT |
1014 | goto out; |
1015 | } | |
1016 | ||
1017 | if (nd->intent.open.flags & O_CREAT) { | |
1018 | nfs_begin_data_update(dir); | |
02a913a7 | 1019 | res = nfs4_atomic_open(dir, dentry, nd); |
1da177e4 LT |
1020 | nfs_end_data_update(dir); |
1021 | } else | |
02a913a7 | 1022 | res = nfs4_atomic_open(dir, dentry, nd); |
1da177e4 | 1023 | unlock_kernel(); |
02a913a7 TM |
1024 | if (IS_ERR(res)) { |
1025 | error = PTR_ERR(res); | |
1da177e4 LT |
1026 | switch (error) { |
1027 | /* Make a negative dentry */ | |
1028 | case -ENOENT: | |
02a913a7 TM |
1029 | res = NULL; |
1030 | goto out; | |
1da177e4 | 1031 | /* This turned out not to be a regular file */ |
6f926b5b TM |
1032 | case -EISDIR: |
1033 | case -ENOTDIR: | |
1034 | goto no_open; | |
1da177e4 LT |
1035 | case -ELOOP: |
1036 | if (!(nd->intent.open.flags & O_NOFOLLOW)) | |
1037 | goto no_open; | |
1da177e4 LT |
1038 | /* case -EINVAL: */ |
1039 | default: | |
1da177e4 LT |
1040 | goto out; |
1041 | } | |
02a913a7 | 1042 | } else if (res != NULL) |
1da177e4 | 1043 | dentry = res; |
1da177e4 LT |
1044 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); |
1045 | out: | |
1046 | return res; | |
1047 | no_open: | |
1048 | return nfs_lookup(dir, dentry, nd); | |
1049 | } | |
1050 | ||
1051 | static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd) | |
1052 | { | |
1053 | struct dentry *parent = NULL; | |
1054 | struct inode *inode = dentry->d_inode; | |
1055 | struct inode *dir; | |
1056 | unsigned long verifier; | |
1057 | int openflags, ret = 0; | |
1058 | ||
1059 | parent = dget_parent(dentry); | |
1060 | dir = parent->d_inode; | |
1061 | if (!is_atomic_open(dir, nd)) | |
1062 | goto no_open; | |
1063 | /* We can't create new files in nfs_open_revalidate(), so we | |
1064 | * optimize away revalidation of negative dentries. | |
1065 | */ | |
1066 | if (inode == NULL) | |
1067 | goto out; | |
1068 | /* NFS only supports OPEN on regular files */ | |
1069 | if (!S_ISREG(inode->i_mode)) | |
1070 | goto no_open; | |
1071 | openflags = nd->intent.open.flags; | |
1072 | /* We cannot do exclusive creation on a positive dentry */ | |
1073 | if ((openflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL)) | |
1074 | goto no_open; | |
1075 | /* We can't create new files, or truncate existing ones here */ | |
1076 | openflags &= ~(O_CREAT|O_TRUNC); | |
1077 | ||
1078 | /* | |
1b1dcc1b | 1079 | * Note: we're not holding inode->i_mutex and so may be racing with |
1da177e4 LT |
1080 | * operations that change the directory. We therefore save the |
1081 | * change attribute *before* we do the RPC call. | |
1082 | */ | |
1083 | lock_kernel(); | |
1084 | verifier = nfs_save_change_attribute(dir); | |
02a913a7 | 1085 | ret = nfs4_open_revalidate(dir, dentry, openflags, nd); |
1da177e4 | 1086 | if (!ret) |
8fb559f8 | 1087 | nfs_set_verifier(dentry, verifier); |
1da177e4 LT |
1088 | unlock_kernel(); |
1089 | out: | |
1090 | dput(parent); | |
1091 | if (!ret) | |
1092 | d_drop(dentry); | |
1093 | return ret; | |
1094 | no_open: | |
1095 | dput(parent); | |
1096 | if (inode != NULL && nfs_have_delegation(inode, FMODE_READ)) | |
1097 | return 1; | |
1098 | return nfs_lookup_revalidate(dentry, nd); | |
1099 | } | |
1100 | #endif /* CONFIG_NFSV4 */ | |
1101 | ||
1102 | static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc) | |
1103 | { | |
01cce933 | 1104 | struct dentry *parent = desc->file->f_path.dentry; |
1da177e4 LT |
1105 | struct inode *dir = parent->d_inode; |
1106 | struct nfs_entry *entry = desc->entry; | |
1107 | struct dentry *dentry, *alias; | |
1108 | struct qstr name = { | |
1109 | .name = entry->name, | |
1110 | .len = entry->len, | |
1111 | }; | |
1112 | struct inode *inode; | |
1113 | ||
1114 | switch (name.len) { | |
1115 | case 2: | |
1116 | if (name.name[0] == '.' && name.name[1] == '.') | |
1117 | return dget_parent(parent); | |
1118 | break; | |
1119 | case 1: | |
1120 | if (name.name[0] == '.') | |
1121 | return dget(parent); | |
1122 | } | |
1123 | name.hash = full_name_hash(name.name, name.len); | |
1124 | dentry = d_lookup(parent, &name); | |
df1d5d23 | 1125 | if (dentry != NULL) { |
ef75c797 TM |
1126 | /* Is this a positive dentry that matches the readdir info? */ |
1127 | if (dentry->d_inode != NULL && | |
1128 | (NFS_FILEID(dentry->d_inode) == entry->ino || | |
1129 | d_mountpoint(dentry))) { | |
1130 | if (!desc->plus || entry->fh->size == 0) | |
1131 | return dentry; | |
1132 | if (nfs_compare_fh(NFS_FH(dentry->d_inode), | |
1133 | entry->fh) == 0) | |
1134 | goto out_renew; | |
1135 | } | |
df1d5d23 TM |
1136 | /* No, so d_drop to allow one to be created */ |
1137 | d_drop(dentry); | |
1138 | dput(dentry); | |
1139 | } | |
1da177e4 LT |
1140 | if (!desc->plus || !(entry->fattr->valid & NFS_ATTR_FATTR)) |
1141 | return NULL; | |
54af3bb5 TM |
1142 | if (name.len > NFS_SERVER(dir)->namelen) |
1143 | return NULL; | |
1b1dcc1b | 1144 | /* Note: caller is already holding the dir->i_mutex! */ |
1da177e4 LT |
1145 | dentry = d_alloc(parent, &name); |
1146 | if (dentry == NULL) | |
1147 | return NULL; | |
1148 | dentry->d_op = NFS_PROTO(dir)->dentry_ops; | |
1149 | inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr); | |
03f28e3a | 1150 | if (IS_ERR(inode)) { |
1da177e4 LT |
1151 | dput(dentry); |
1152 | return NULL; | |
1153 | } | |
54ceac45 DH |
1154 | |
1155 | alias = d_materialise_unique(dentry, inode); | |
1da177e4 LT |
1156 | if (alias != NULL) { |
1157 | dput(dentry); | |
9eaef27b TM |
1158 | if (IS_ERR(alias)) |
1159 | return NULL; | |
1da177e4 LT |
1160 | dentry = alias; |
1161 | } | |
54ceac45 | 1162 | |
c79ba787 | 1163 | out_renew: |
8fb559f8 | 1164 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); |
c79ba787 | 1165 | return dentry; |
1da177e4 LT |
1166 | } |
1167 | ||
1168 | /* | |
1169 | * Code common to create, mkdir, and mknod. | |
1170 | */ | |
1171 | int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle, | |
1172 | struct nfs_fattr *fattr) | |
1173 | { | |
1174 | struct inode *inode; | |
1175 | int error = -EACCES; | |
1176 | ||
1177 | /* We may have been initialized further down */ | |
1178 | if (dentry->d_inode) | |
1179 | return 0; | |
1180 | if (fhandle->size == 0) { | |
1181 | struct inode *dir = dentry->d_parent->d_inode; | |
1182 | error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr); | |
1183 | if (error) | |
4f390c15 | 1184 | return error; |
1da177e4 LT |
1185 | } |
1186 | if (!(fattr->valid & NFS_ATTR_FATTR)) { | |
1187 | struct nfs_server *server = NFS_SB(dentry->d_sb); | |
8fa5c000 | 1188 | error = server->nfs_client->rpc_ops->getattr(server, fhandle, fattr); |
1da177e4 | 1189 | if (error < 0) |
4f390c15 | 1190 | return error; |
1da177e4 | 1191 | } |
1da177e4 | 1192 | inode = nfs_fhget(dentry->d_sb, fhandle, fattr); |
03f28e3a TM |
1193 | error = PTR_ERR(inode); |
1194 | if (IS_ERR(inode)) | |
4f390c15 | 1195 | return error; |
1da177e4 | 1196 | d_instantiate(dentry, inode); |
fd684071 TM |
1197 | if (d_unhashed(dentry)) |
1198 | d_rehash(dentry); | |
1da177e4 | 1199 | return 0; |
1da177e4 LT |
1200 | } |
1201 | ||
1202 | /* | |
1203 | * Following a failed create operation, we drop the dentry rather | |
1204 | * than retain a negative dentry. This avoids a problem in the event | |
1205 | * that the operation succeeded on the server, but an error in the | |
1206 | * reply path made it appear to have failed. | |
1207 | */ | |
1208 | static int nfs_create(struct inode *dir, struct dentry *dentry, int mode, | |
1209 | struct nameidata *nd) | |
1210 | { | |
1211 | struct iattr attr; | |
1212 | int error; | |
1213 | int open_flags = 0; | |
1214 | ||
1e7cb3dc CL |
1215 | dfprintk(VFS, "NFS: create(%s/%ld), %s\n", |
1216 | dir->i_sb->s_id, dir->i_ino, dentry->d_name.name); | |
1da177e4 LT |
1217 | |
1218 | attr.ia_mode = mode; | |
1219 | attr.ia_valid = ATTR_MODE; | |
1220 | ||
ad389da7 | 1221 | if ((nd->flags & LOOKUP_CREATE) != 0) |
1da177e4 LT |
1222 | open_flags = nd->intent.open.flags; |
1223 | ||
1224 | lock_kernel(); | |
1225 | nfs_begin_data_update(dir); | |
02a913a7 | 1226 | error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, nd); |
1da177e4 LT |
1227 | nfs_end_data_update(dir); |
1228 | if (error != 0) | |
1229 | goto out_err; | |
1da177e4 LT |
1230 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); |
1231 | unlock_kernel(); | |
1232 | return 0; | |
1233 | out_err: | |
1234 | unlock_kernel(); | |
1235 | d_drop(dentry); | |
1236 | return error; | |
1237 | } | |
1238 | ||
1239 | /* | |
1240 | * See comments for nfs_proc_create regarding failed operations. | |
1241 | */ | |
1242 | static int | |
1243 | nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev) | |
1244 | { | |
1245 | struct iattr attr; | |
1246 | int status; | |
1247 | ||
1e7cb3dc CL |
1248 | dfprintk(VFS, "NFS: mknod(%s/%ld), %s\n", |
1249 | dir->i_sb->s_id, dir->i_ino, dentry->d_name.name); | |
1da177e4 LT |
1250 | |
1251 | if (!new_valid_dev(rdev)) | |
1252 | return -EINVAL; | |
1253 | ||
1254 | attr.ia_mode = mode; | |
1255 | attr.ia_valid = ATTR_MODE; | |
1256 | ||
1257 | lock_kernel(); | |
1258 | nfs_begin_data_update(dir); | |
1259 | status = NFS_PROTO(dir)->mknod(dir, dentry, &attr, rdev); | |
1260 | nfs_end_data_update(dir); | |
1261 | if (status != 0) | |
1262 | goto out_err; | |
1da177e4 LT |
1263 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); |
1264 | unlock_kernel(); | |
1265 | return 0; | |
1266 | out_err: | |
1267 | unlock_kernel(); | |
1268 | d_drop(dentry); | |
1269 | return status; | |
1270 | } | |
1271 | ||
1272 | /* | |
1273 | * See comments for nfs_proc_create regarding failed operations. | |
1274 | */ | |
1275 | static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
1276 | { | |
1277 | struct iattr attr; | |
1278 | int error; | |
1279 | ||
1e7cb3dc CL |
1280 | dfprintk(VFS, "NFS: mkdir(%s/%ld), %s\n", |
1281 | dir->i_sb->s_id, dir->i_ino, dentry->d_name.name); | |
1da177e4 LT |
1282 | |
1283 | attr.ia_valid = ATTR_MODE; | |
1284 | attr.ia_mode = mode | S_IFDIR; | |
1285 | ||
1286 | lock_kernel(); | |
1287 | nfs_begin_data_update(dir); | |
1288 | error = NFS_PROTO(dir)->mkdir(dir, dentry, &attr); | |
1289 | nfs_end_data_update(dir); | |
1290 | if (error != 0) | |
1291 | goto out_err; | |
1da177e4 LT |
1292 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); |
1293 | unlock_kernel(); | |
1294 | return 0; | |
1295 | out_err: | |
1296 | d_drop(dentry); | |
1297 | unlock_kernel(); | |
1298 | return error; | |
1299 | } | |
1300 | ||
1301 | static int nfs_rmdir(struct inode *dir, struct dentry *dentry) | |
1302 | { | |
1303 | int error; | |
1304 | ||
1e7cb3dc CL |
1305 | dfprintk(VFS, "NFS: rmdir(%s/%ld), %s\n", |
1306 | dir->i_sb->s_id, dir->i_ino, dentry->d_name.name); | |
1da177e4 LT |
1307 | |
1308 | lock_kernel(); | |
1309 | nfs_begin_data_update(dir); | |
1310 | error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name); | |
1311 | /* Ensure the VFS deletes this inode */ | |
1312 | if (error == 0 && dentry->d_inode != NULL) | |
ce71ec36 | 1313 | clear_nlink(dentry->d_inode); |
1da177e4 LT |
1314 | nfs_end_data_update(dir); |
1315 | unlock_kernel(); | |
1316 | ||
1317 | return error; | |
1318 | } | |
1319 | ||
1320 | static int nfs_sillyrename(struct inode *dir, struct dentry *dentry) | |
1321 | { | |
1322 | static unsigned int sillycounter; | |
4e769b93 | 1323 | const int fileidsize = sizeof(NFS_FILEID(dentry->d_inode))*2; |
1da177e4 | 1324 | const int countersize = sizeof(sillycounter)*2; |
4e769b93 | 1325 | const int slen = sizeof(".nfs")+fileidsize+countersize-1; |
1da177e4 LT |
1326 | char silly[slen+1]; |
1327 | struct qstr qsilly; | |
1328 | struct dentry *sdentry; | |
1329 | int error = -EIO; | |
1330 | ||
1331 | dfprintk(VFS, "NFS: silly-rename(%s/%s, ct=%d)\n", | |
1332 | dentry->d_parent->d_name.name, dentry->d_name.name, | |
1333 | atomic_read(&dentry->d_count)); | |
91d5b470 | 1334 | nfs_inc_stats(dir, NFSIOS_SILLYRENAME); |
1da177e4 | 1335 | |
1da177e4 LT |
1336 | /* |
1337 | * We don't allow a dentry to be silly-renamed twice. | |
1338 | */ | |
1339 | error = -EBUSY; | |
1340 | if (dentry->d_flags & DCACHE_NFSFS_RENAMED) | |
1341 | goto out; | |
1342 | ||
4e769b93 PS |
1343 | sprintf(silly, ".nfs%*.*Lx", |
1344 | fileidsize, fileidsize, | |
1345 | (unsigned long long)NFS_FILEID(dentry->d_inode)); | |
1da177e4 | 1346 | |
34ea8188 TM |
1347 | /* Return delegation in anticipation of the rename */ |
1348 | nfs_inode_return_delegation(dentry->d_inode); | |
1349 | ||
1da177e4 LT |
1350 | sdentry = NULL; |
1351 | do { | |
1352 | char *suffix = silly + slen - countersize; | |
1353 | ||
1354 | dput(sdentry); | |
1355 | sillycounter++; | |
1356 | sprintf(suffix, "%*.*x", countersize, countersize, sillycounter); | |
1357 | ||
1e7cb3dc CL |
1358 | dfprintk(VFS, "NFS: trying to rename %s to %s\n", |
1359 | dentry->d_name.name, silly); | |
1da177e4 LT |
1360 | |
1361 | sdentry = lookup_one_len(silly, dentry->d_parent, slen); | |
1362 | /* | |
1363 | * N.B. Better to return EBUSY here ... it could be | |
1364 | * dangerous to delete the file while it's in use. | |
1365 | */ | |
1366 | if (IS_ERR(sdentry)) | |
1367 | goto out; | |
1368 | } while(sdentry->d_inode != NULL); /* need negative lookup */ | |
1369 | ||
1370 | qsilly.name = silly; | |
1371 | qsilly.len = strlen(silly); | |
1372 | nfs_begin_data_update(dir); | |
1373 | if (dentry->d_inode) { | |
1374 | nfs_begin_data_update(dentry->d_inode); | |
1375 | error = NFS_PROTO(dir)->rename(dir, &dentry->d_name, | |
1376 | dir, &qsilly); | |
5ba7cc48 | 1377 | nfs_mark_for_revalidate(dentry->d_inode); |
1da177e4 LT |
1378 | nfs_end_data_update(dentry->d_inode); |
1379 | } else | |
1380 | error = NFS_PROTO(dir)->rename(dir, &dentry->d_name, | |
1381 | dir, &qsilly); | |
1382 | nfs_end_data_update(dir); | |
1383 | if (!error) { | |
1da177e4 LT |
1384 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); |
1385 | d_move(dentry, sdentry); | |
e4eff1a6 | 1386 | error = nfs_async_unlink(dir, dentry); |
1da177e4 LT |
1387 | /* If we return 0 we don't unlink */ |
1388 | } | |
1389 | dput(sdentry); | |
1390 | out: | |
1391 | return error; | |
1392 | } | |
1393 | ||
1394 | /* | |
1395 | * Remove a file after making sure there are no pending writes, | |
1396 | * and after checking that the file has only one user. | |
1397 | * | |
1398 | * We invalidate the attribute cache and free the inode prior to the operation | |
1399 | * to avoid possible races if the server reuses the inode. | |
1400 | */ | |
1401 | static int nfs_safe_remove(struct dentry *dentry) | |
1402 | { | |
1403 | struct inode *dir = dentry->d_parent->d_inode; | |
1404 | struct inode *inode = dentry->d_inode; | |
1405 | int error = -EBUSY; | |
1406 | ||
1407 | dfprintk(VFS, "NFS: safe_remove(%s/%s)\n", | |
1408 | dentry->d_parent->d_name.name, dentry->d_name.name); | |
1409 | ||
1410 | /* If the dentry was sillyrenamed, we simply call d_delete() */ | |
1411 | if (dentry->d_flags & DCACHE_NFSFS_RENAMED) { | |
1412 | error = 0; | |
1413 | goto out; | |
1414 | } | |
1415 | ||
1416 | nfs_begin_data_update(dir); | |
1417 | if (inode != NULL) { | |
cae7a073 | 1418 | nfs_inode_return_delegation(inode); |
1da177e4 LT |
1419 | nfs_begin_data_update(inode); |
1420 | error = NFS_PROTO(dir)->remove(dir, &dentry->d_name); | |
1421 | /* The VFS may want to delete this inode */ | |
1422 | if (error == 0) | |
9a53c3a7 | 1423 | drop_nlink(inode); |
5ba7cc48 | 1424 | nfs_mark_for_revalidate(inode); |
1da177e4 LT |
1425 | nfs_end_data_update(inode); |
1426 | } else | |
1427 | error = NFS_PROTO(dir)->remove(dir, &dentry->d_name); | |
1428 | nfs_end_data_update(dir); | |
1429 | out: | |
1430 | return error; | |
1431 | } | |
1432 | ||
1433 | /* We do silly rename. In case sillyrename() returns -EBUSY, the inode | |
1434 | * belongs to an active ".nfs..." file and we return -EBUSY. | |
1435 | * | |
1436 | * If sillyrename() returns 0, we do nothing, otherwise we unlink. | |
1437 | */ | |
1438 | static int nfs_unlink(struct inode *dir, struct dentry *dentry) | |
1439 | { | |
1440 | int error; | |
1441 | int need_rehash = 0; | |
1442 | ||
1443 | dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id, | |
1444 | dir->i_ino, dentry->d_name.name); | |
1445 | ||
1446 | lock_kernel(); | |
1447 | spin_lock(&dcache_lock); | |
1448 | spin_lock(&dentry->d_lock); | |
1449 | if (atomic_read(&dentry->d_count) > 1) { | |
1450 | spin_unlock(&dentry->d_lock); | |
1451 | spin_unlock(&dcache_lock); | |
ccfeb506 TM |
1452 | /* Start asynchronous writeout of the inode */ |
1453 | write_inode_now(dentry->d_inode, 0); | |
1da177e4 LT |
1454 | error = nfs_sillyrename(dir, dentry); |
1455 | unlock_kernel(); | |
1456 | return error; | |
1457 | } | |
1458 | if (!d_unhashed(dentry)) { | |
1459 | __d_drop(dentry); | |
1460 | need_rehash = 1; | |
1461 | } | |
1462 | spin_unlock(&dentry->d_lock); | |
1463 | spin_unlock(&dcache_lock); | |
1464 | error = nfs_safe_remove(dentry); | |
1465 | if (!error) { | |
1da177e4 LT |
1466 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); |
1467 | } else if (need_rehash) | |
1468 | d_rehash(dentry); | |
1469 | unlock_kernel(); | |
1470 | return error; | |
1471 | } | |
1472 | ||
873101b3 CL |
1473 | /* |
1474 | * To create a symbolic link, most file systems instantiate a new inode, | |
1475 | * add a page to it containing the path, then write it out to the disk | |
1476 | * using prepare_write/commit_write. | |
1477 | * | |
1478 | * Unfortunately the NFS client can't create the in-core inode first | |
1479 | * because it needs a file handle to create an in-core inode (see | |
1480 | * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the | |
1481 | * symlink request has completed on the server. | |
1482 | * | |
1483 | * So instead we allocate a raw page, copy the symname into it, then do | |
1484 | * the SYMLINK request with the page as the buffer. If it succeeds, we | |
1485 | * now have a new file handle and can instantiate an in-core NFS inode | |
1486 | * and move the raw page into its mapping. | |
1487 | */ | |
1488 | static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) | |
1da177e4 | 1489 | { |
873101b3 CL |
1490 | struct pagevec lru_pvec; |
1491 | struct page *page; | |
1492 | char *kaddr; | |
1da177e4 | 1493 | struct iattr attr; |
873101b3 | 1494 | unsigned int pathlen = strlen(symname); |
1da177e4 LT |
1495 | int error; |
1496 | ||
1497 | dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s)\n", dir->i_sb->s_id, | |
1498 | dir->i_ino, dentry->d_name.name, symname); | |
1499 | ||
873101b3 CL |
1500 | if (pathlen > PAGE_SIZE) |
1501 | return -ENAMETOOLONG; | |
1da177e4 | 1502 | |
873101b3 CL |
1503 | attr.ia_mode = S_IFLNK | S_IRWXUGO; |
1504 | attr.ia_valid = ATTR_MODE; | |
1da177e4 LT |
1505 | |
1506 | lock_kernel(); | |
873101b3 | 1507 | |
83d93f22 | 1508 | page = alloc_page(GFP_HIGHUSER); |
873101b3 CL |
1509 | if (!page) { |
1510 | unlock_kernel(); | |
1511 | return -ENOMEM; | |
1512 | } | |
1513 | ||
1514 | kaddr = kmap_atomic(page, KM_USER0); | |
1515 | memcpy(kaddr, symname, pathlen); | |
1516 | if (pathlen < PAGE_SIZE) | |
1517 | memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen); | |
1518 | kunmap_atomic(kaddr, KM_USER0); | |
1519 | ||
1da177e4 | 1520 | nfs_begin_data_update(dir); |
94a6d753 | 1521 | error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr); |
1da177e4 | 1522 | nfs_end_data_update(dir); |
873101b3 CL |
1523 | if (error != 0) { |
1524 | dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s) error %d\n", | |
1525 | dir->i_sb->s_id, dir->i_ino, | |
1526 | dentry->d_name.name, symname, error); | |
1da177e4 | 1527 | d_drop(dentry); |
873101b3 CL |
1528 | __free_page(page); |
1529 | unlock_kernel(); | |
1530 | return error; | |
1531 | } | |
1532 | ||
1533 | /* | |
1534 | * No big deal if we can't add this page to the page cache here. | |
1535 | * READLINK will get the missing page from the server if needed. | |
1536 | */ | |
1537 | pagevec_init(&lru_pvec, 0); | |
1538 | if (!add_to_page_cache(page, dentry->d_inode->i_mapping, 0, | |
1539 | GFP_KERNEL)) { | |
39cf8a13 CL |
1540 | pagevec_add(&lru_pvec, page); |
1541 | pagevec_lru_add(&lru_pvec); | |
873101b3 CL |
1542 | SetPageUptodate(page); |
1543 | unlock_page(page); | |
1544 | } else | |
1545 | __free_page(page); | |
1546 | ||
1da177e4 | 1547 | unlock_kernel(); |
873101b3 | 1548 | return 0; |
1da177e4 LT |
1549 | } |
1550 | ||
1551 | static int | |
1552 | nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) | |
1553 | { | |
1554 | struct inode *inode = old_dentry->d_inode; | |
1555 | int error; | |
1556 | ||
1557 | dfprintk(VFS, "NFS: link(%s/%s -> %s/%s)\n", | |
1558 | old_dentry->d_parent->d_name.name, old_dentry->d_name.name, | |
1559 | dentry->d_parent->d_name.name, dentry->d_name.name); | |
1560 | ||
1da177e4 | 1561 | lock_kernel(); |
1da177e4 LT |
1562 | nfs_begin_data_update(dir); |
1563 | nfs_begin_data_update(inode); | |
1564 | error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name); | |
cf809556 TM |
1565 | if (error == 0) { |
1566 | atomic_inc(&inode->i_count); | |
1567 | d_instantiate(dentry, inode); | |
1568 | } | |
1da177e4 LT |
1569 | nfs_end_data_update(inode); |
1570 | nfs_end_data_update(dir); | |
1571 | unlock_kernel(); | |
1572 | return error; | |
1573 | } | |
1574 | ||
1575 | /* | |
1576 | * RENAME | |
1577 | * FIXME: Some nfsds, like the Linux user space nfsd, may generate a | |
1578 | * different file handle for the same inode after a rename (e.g. when | |
1579 | * moving to a different directory). A fail-safe method to do so would | |
1580 | * be to look up old_dir/old_name, create a link to new_dir/new_name and | |
1581 | * rename the old file using the sillyrename stuff. This way, the original | |
1582 | * file in old_dir will go away when the last process iput()s the inode. | |
1583 | * | |
1584 | * FIXED. | |
1585 | * | |
1586 | * It actually works quite well. One needs to have the possibility for | |
1587 | * at least one ".nfs..." file in each directory the file ever gets | |
1588 | * moved or linked to which happens automagically with the new | |
1589 | * implementation that only depends on the dcache stuff instead of | |
1590 | * using the inode layer | |
1591 | * | |
1592 | * Unfortunately, things are a little more complicated than indicated | |
1593 | * above. For a cross-directory move, we want to make sure we can get | |
1594 | * rid of the old inode after the operation. This means there must be | |
1595 | * no pending writes (if it's a file), and the use count must be 1. | |
1596 | * If these conditions are met, we can drop the dentries before doing | |
1597 | * the rename. | |
1598 | */ | |
1599 | static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry, | |
1600 | struct inode *new_dir, struct dentry *new_dentry) | |
1601 | { | |
1602 | struct inode *old_inode = old_dentry->d_inode; | |
1603 | struct inode *new_inode = new_dentry->d_inode; | |
1604 | struct dentry *dentry = NULL, *rehash = NULL; | |
1605 | int error = -EBUSY; | |
1606 | ||
1607 | /* | |
1608 | * To prevent any new references to the target during the rename, | |
1609 | * we unhash the dentry and free the inode in advance. | |
1610 | */ | |
1611 | lock_kernel(); | |
1612 | if (!d_unhashed(new_dentry)) { | |
1613 | d_drop(new_dentry); | |
1614 | rehash = new_dentry; | |
1615 | } | |
1616 | ||
1617 | dfprintk(VFS, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n", | |
1618 | old_dentry->d_parent->d_name.name, old_dentry->d_name.name, | |
1619 | new_dentry->d_parent->d_name.name, new_dentry->d_name.name, | |
1620 | atomic_read(&new_dentry->d_count)); | |
1621 | ||
1622 | /* | |
1623 | * First check whether the target is busy ... we can't | |
1624 | * safely do _any_ rename if the target is in use. | |
1625 | * | |
1626 | * For files, make a copy of the dentry and then do a | |
1627 | * silly-rename. If the silly-rename succeeds, the | |
1628 | * copied dentry is hashed and becomes the new target. | |
1629 | */ | |
1630 | if (!new_inode) | |
1631 | goto go_ahead; | |
6fe43f9e TM |
1632 | if (S_ISDIR(new_inode->i_mode)) { |
1633 | error = -EISDIR; | |
1634 | if (!S_ISDIR(old_inode->i_mode)) | |
1635 | goto out; | |
1636 | } else if (atomic_read(&new_dentry->d_count) > 2) { | |
1da177e4 LT |
1637 | int err; |
1638 | /* copy the target dentry's name */ | |
1639 | dentry = d_alloc(new_dentry->d_parent, | |
1640 | &new_dentry->d_name); | |
1641 | if (!dentry) | |
1642 | goto out; | |
1643 | ||
1644 | /* silly-rename the existing target ... */ | |
1645 | err = nfs_sillyrename(new_dir, new_dentry); | |
1646 | if (!err) { | |
1647 | new_dentry = rehash = dentry; | |
1648 | new_inode = NULL; | |
1649 | /* instantiate the replacement target */ | |
1650 | d_instantiate(new_dentry, NULL); | |
7a13e932 JJ |
1651 | } else if (atomic_read(&new_dentry->d_count) > 1) |
1652 | /* dentry still busy? */ | |
1da177e4 | 1653 | goto out; |
20509f1b | 1654 | } else |
9a53c3a7 | 1655 | drop_nlink(new_inode); |
1da177e4 LT |
1656 | |
1657 | go_ahead: | |
1658 | /* | |
1659 | * ... prune child dentries and writebacks if needed. | |
1660 | */ | |
1661 | if (atomic_read(&old_dentry->d_count) > 1) { | |
e1552e19 TM |
1662 | if (S_ISREG(old_inode->i_mode)) |
1663 | nfs_wb_all(old_inode); | |
1da177e4 LT |
1664 | shrink_dcache_parent(old_dentry); |
1665 | } | |
cae7a073 | 1666 | nfs_inode_return_delegation(old_inode); |
1da177e4 | 1667 | |
24174119 TM |
1668 | if (new_inode != NULL) { |
1669 | nfs_inode_return_delegation(new_inode); | |
1da177e4 | 1670 | d_delete(new_dentry); |
24174119 | 1671 | } |
1da177e4 LT |
1672 | |
1673 | nfs_begin_data_update(old_dir); | |
1674 | nfs_begin_data_update(new_dir); | |
1675 | nfs_begin_data_update(old_inode); | |
1676 | error = NFS_PROTO(old_dir)->rename(old_dir, &old_dentry->d_name, | |
1677 | new_dir, &new_dentry->d_name); | |
5ba7cc48 | 1678 | nfs_mark_for_revalidate(old_inode); |
1da177e4 LT |
1679 | nfs_end_data_update(old_inode); |
1680 | nfs_end_data_update(new_dir); | |
1681 | nfs_end_data_update(old_dir); | |
1682 | out: | |
1683 | if (rehash) | |
1684 | d_rehash(rehash); | |
1685 | if (!error) { | |
349457cc | 1686 | d_move(old_dentry, new_dentry); |
8fb559f8 CL |
1687 | nfs_set_verifier(new_dentry, |
1688 | nfs_save_change_attribute(new_dir)); | |
1da177e4 LT |
1689 | } |
1690 | ||
1691 | /* new dentry created? */ | |
1692 | if (dentry) | |
1693 | dput(dentry); | |
1694 | unlock_kernel(); | |
1695 | return error; | |
1696 | } | |
1697 | ||
cfcea3e8 TM |
1698 | static DEFINE_SPINLOCK(nfs_access_lru_lock); |
1699 | static LIST_HEAD(nfs_access_lru_list); | |
1700 | static atomic_long_t nfs_access_nr_entries; | |
1701 | ||
1c3c07e9 TM |
1702 | static void nfs_access_free_entry(struct nfs_access_entry *entry) |
1703 | { | |
1704 | put_rpccred(entry->cred); | |
1705 | kfree(entry); | |
cfcea3e8 TM |
1706 | smp_mb__before_atomic_dec(); |
1707 | atomic_long_dec(&nfs_access_nr_entries); | |
1708 | smp_mb__after_atomic_dec(); | |
1c3c07e9 TM |
1709 | } |
1710 | ||
979df72e TM |
1711 | int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask) |
1712 | { | |
1713 | LIST_HEAD(head); | |
1714 | struct nfs_inode *nfsi; | |
1715 | struct nfs_access_entry *cache; | |
1716 | ||
979df72e | 1717 | restart: |
a50f7951 | 1718 | spin_lock(&nfs_access_lru_lock); |
979df72e TM |
1719 | list_for_each_entry(nfsi, &nfs_access_lru_list, access_cache_inode_lru) { |
1720 | struct inode *inode; | |
1721 | ||
1722 | if (nr_to_scan-- == 0) | |
1723 | break; | |
1724 | inode = igrab(&nfsi->vfs_inode); | |
1725 | if (inode == NULL) | |
1726 | continue; | |
1727 | spin_lock(&inode->i_lock); | |
1728 | if (list_empty(&nfsi->access_cache_entry_lru)) | |
1729 | goto remove_lru_entry; | |
1730 | cache = list_entry(nfsi->access_cache_entry_lru.next, | |
1731 | struct nfs_access_entry, lru); | |
1732 | list_move(&cache->lru, &head); | |
1733 | rb_erase(&cache->rb_node, &nfsi->access_cache); | |
1734 | if (!list_empty(&nfsi->access_cache_entry_lru)) | |
1735 | list_move_tail(&nfsi->access_cache_inode_lru, | |
1736 | &nfs_access_lru_list); | |
1737 | else { | |
1738 | remove_lru_entry: | |
1739 | list_del_init(&nfsi->access_cache_inode_lru); | |
1740 | clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags); | |
1741 | } | |
1742 | spin_unlock(&inode->i_lock); | |
a50f7951 | 1743 | spin_unlock(&nfs_access_lru_lock); |
979df72e TM |
1744 | iput(inode); |
1745 | goto restart; | |
1746 | } | |
1747 | spin_unlock(&nfs_access_lru_lock); | |
1748 | while (!list_empty(&head)) { | |
1749 | cache = list_entry(head.next, struct nfs_access_entry, lru); | |
1750 | list_del(&cache->lru); | |
1751 | nfs_access_free_entry(cache); | |
1752 | } | |
1753 | return (atomic_long_read(&nfs_access_nr_entries) / 100) * sysctl_vfs_cache_pressure; | |
1754 | } | |
1755 | ||
1c3c07e9 | 1756 | static void __nfs_access_zap_cache(struct inode *inode) |
1da177e4 | 1757 | { |
55296809 | 1758 | struct nfs_inode *nfsi = NFS_I(inode); |
1c3c07e9 TM |
1759 | struct rb_root *root_node = &nfsi->access_cache; |
1760 | struct rb_node *n, *dispose = NULL; | |
1761 | struct nfs_access_entry *entry; | |
1762 | ||
1763 | /* Unhook entries from the cache */ | |
1764 | while ((n = rb_first(root_node)) != NULL) { | |
1765 | entry = rb_entry(n, struct nfs_access_entry, rb_node); | |
1766 | rb_erase(n, root_node); | |
cfcea3e8 | 1767 | list_del(&entry->lru); |
1c3c07e9 TM |
1768 | n->rb_left = dispose; |
1769 | dispose = n; | |
1770 | } | |
1771 | nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS; | |
1772 | spin_unlock(&inode->i_lock); | |
1da177e4 | 1773 | |
1c3c07e9 TM |
1774 | /* Now kill them all! */ |
1775 | while (dispose != NULL) { | |
1776 | n = dispose; | |
1777 | dispose = n->rb_left; | |
1778 | nfs_access_free_entry(rb_entry(n, struct nfs_access_entry, rb_node)); | |
1779 | } | |
1da177e4 LT |
1780 | } |
1781 | ||
1c3c07e9 | 1782 | void nfs_access_zap_cache(struct inode *inode) |
1da177e4 | 1783 | { |
cfcea3e8 TM |
1784 | /* Remove from global LRU init */ |
1785 | if (test_and_clear_bit(NFS_INO_ACL_LRU_SET, &NFS_FLAGS(inode))) { | |
1786 | spin_lock(&nfs_access_lru_lock); | |
1787 | list_del_init(&NFS_I(inode)->access_cache_inode_lru); | |
1788 | spin_unlock(&nfs_access_lru_lock); | |
1789 | } | |
1790 | ||
1c3c07e9 TM |
1791 | spin_lock(&inode->i_lock); |
1792 | /* This will release the spinlock */ | |
1793 | __nfs_access_zap_cache(inode); | |
1794 | } | |
1da177e4 | 1795 | |
1c3c07e9 TM |
1796 | static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, struct rpc_cred *cred) |
1797 | { | |
1798 | struct rb_node *n = NFS_I(inode)->access_cache.rb_node; | |
1799 | struct nfs_access_entry *entry; | |
1800 | ||
1801 | while (n != NULL) { | |
1802 | entry = rb_entry(n, struct nfs_access_entry, rb_node); | |
1803 | ||
1804 | if (cred < entry->cred) | |
1805 | n = n->rb_left; | |
1806 | else if (cred > entry->cred) | |
1807 | n = n->rb_right; | |
1808 | else | |
1809 | return entry; | |
1da177e4 | 1810 | } |
1c3c07e9 TM |
1811 | return NULL; |
1812 | } | |
1813 | ||
af22f94a | 1814 | static int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res) |
1c3c07e9 TM |
1815 | { |
1816 | struct nfs_inode *nfsi = NFS_I(inode); | |
1817 | struct nfs_access_entry *cache; | |
1818 | int err = -ENOENT; | |
1819 | ||
dc59250c | 1820 | spin_lock(&inode->i_lock); |
1c3c07e9 TM |
1821 | if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS) |
1822 | goto out_zap; | |
1823 | cache = nfs_access_search_rbtree(inode, cred); | |
1824 | if (cache == NULL) | |
1825 | goto out; | |
c7e15961 | 1826 | if (!time_in_range(jiffies, cache->jiffies, cache->jiffies + NFS_ATTRTIMEO(inode))) |
1c3c07e9 TM |
1827 | goto out_stale; |
1828 | res->jiffies = cache->jiffies; | |
1829 | res->cred = cache->cred; | |
1830 | res->mask = cache->mask; | |
cfcea3e8 | 1831 | list_move_tail(&cache->lru, &nfsi->access_cache_entry_lru); |
1c3c07e9 TM |
1832 | err = 0; |
1833 | out: | |
1834 | spin_unlock(&inode->i_lock); | |
1835 | return err; | |
1836 | out_stale: | |
1837 | rb_erase(&cache->rb_node, &nfsi->access_cache); | |
cfcea3e8 | 1838 | list_del(&cache->lru); |
1c3c07e9 TM |
1839 | spin_unlock(&inode->i_lock); |
1840 | nfs_access_free_entry(cache); | |
1841 | return -ENOENT; | |
1842 | out_zap: | |
1843 | /* This will release the spinlock */ | |
1844 | __nfs_access_zap_cache(inode); | |
1845 | return -ENOENT; | |
1846 | } | |
1847 | ||
1848 | static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *set) | |
1849 | { | |
cfcea3e8 TM |
1850 | struct nfs_inode *nfsi = NFS_I(inode); |
1851 | struct rb_root *root_node = &nfsi->access_cache; | |
1c3c07e9 TM |
1852 | struct rb_node **p = &root_node->rb_node; |
1853 | struct rb_node *parent = NULL; | |
1854 | struct nfs_access_entry *entry; | |
1855 | ||
1856 | spin_lock(&inode->i_lock); | |
1857 | while (*p != NULL) { | |
1858 | parent = *p; | |
1859 | entry = rb_entry(parent, struct nfs_access_entry, rb_node); | |
1860 | ||
1861 | if (set->cred < entry->cred) | |
1862 | p = &parent->rb_left; | |
1863 | else if (set->cred > entry->cred) | |
1864 | p = &parent->rb_right; | |
1865 | else | |
1866 | goto found; | |
1867 | } | |
1868 | rb_link_node(&set->rb_node, parent, p); | |
1869 | rb_insert_color(&set->rb_node, root_node); | |
cfcea3e8 | 1870 | list_add_tail(&set->lru, &nfsi->access_cache_entry_lru); |
dc59250c | 1871 | spin_unlock(&inode->i_lock); |
1c3c07e9 TM |
1872 | return; |
1873 | found: | |
1874 | rb_replace_node(parent, &set->rb_node, root_node); | |
cfcea3e8 TM |
1875 | list_add_tail(&set->lru, &nfsi->access_cache_entry_lru); |
1876 | list_del(&entry->lru); | |
1c3c07e9 TM |
1877 | spin_unlock(&inode->i_lock); |
1878 | nfs_access_free_entry(entry); | |
1879 | } | |
1880 | ||
af22f94a | 1881 | static void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set) |
1c3c07e9 TM |
1882 | { |
1883 | struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL); | |
1884 | if (cache == NULL) | |
1885 | return; | |
1886 | RB_CLEAR_NODE(&cache->rb_node); | |
1da177e4 | 1887 | cache->jiffies = set->jiffies; |
1c3c07e9 | 1888 | cache->cred = get_rpccred(set->cred); |
1da177e4 | 1889 | cache->mask = set->mask; |
1c3c07e9 TM |
1890 | |
1891 | nfs_access_add_rbtree(inode, cache); | |
cfcea3e8 TM |
1892 | |
1893 | /* Update accounting */ | |
1894 | smp_mb__before_atomic_inc(); | |
1895 | atomic_long_inc(&nfs_access_nr_entries); | |
1896 | smp_mb__after_atomic_inc(); | |
1897 | ||
1898 | /* Add inode to global LRU list */ | |
1899 | if (!test_and_set_bit(NFS_INO_ACL_LRU_SET, &NFS_FLAGS(inode))) { | |
1900 | spin_lock(&nfs_access_lru_lock); | |
1901 | list_add_tail(&NFS_I(inode)->access_cache_inode_lru, &nfs_access_lru_list); | |
1902 | spin_unlock(&nfs_access_lru_lock); | |
1903 | } | |
1da177e4 LT |
1904 | } |
1905 | ||
1906 | static int nfs_do_access(struct inode *inode, struct rpc_cred *cred, int mask) | |
1907 | { | |
1908 | struct nfs_access_entry cache; | |
1909 | int status; | |
1910 | ||
1911 | status = nfs_access_get_cached(inode, cred, &cache); | |
1912 | if (status == 0) | |
1913 | goto out; | |
1914 | ||
1915 | /* Be clever: ask server to check for all possible rights */ | |
1916 | cache.mask = MAY_EXEC | MAY_WRITE | MAY_READ; | |
1917 | cache.cred = cred; | |
1918 | cache.jiffies = jiffies; | |
1919 | status = NFS_PROTO(inode)->access(inode, &cache); | |
1920 | if (status != 0) | |
1921 | return status; | |
1922 | nfs_access_add_cache(inode, &cache); | |
1923 | out: | |
1924 | if ((cache.mask & mask) == mask) | |
1925 | return 0; | |
1926 | return -EACCES; | |
1927 | } | |
1928 | ||
af22f94a TM |
1929 | static int nfs_open_permission_mask(int openflags) |
1930 | { | |
1931 | int mask = 0; | |
1932 | ||
1933 | if (openflags & FMODE_READ) | |
1934 | mask |= MAY_READ; | |
1935 | if (openflags & FMODE_WRITE) | |
1936 | mask |= MAY_WRITE; | |
1937 | if (openflags & FMODE_EXEC) | |
1938 | mask |= MAY_EXEC; | |
1939 | return mask; | |
1940 | } | |
1941 | ||
1942 | int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags) | |
1943 | { | |
1944 | return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags)); | |
1945 | } | |
1946 | ||
1da177e4 LT |
1947 | int nfs_permission(struct inode *inode, int mask, struct nameidata *nd) |
1948 | { | |
1949 | struct rpc_cred *cred; | |
1950 | int res = 0; | |
1951 | ||
91d5b470 CL |
1952 | nfs_inc_stats(inode, NFSIOS_VFSACCESS); |
1953 | ||
1da177e4 LT |
1954 | if (mask == 0) |
1955 | goto out; | |
1956 | /* Is this sys_access() ? */ | |
1957 | if (nd != NULL && (nd->flags & LOOKUP_ACCESS)) | |
1958 | goto force_lookup; | |
1959 | ||
1960 | switch (inode->i_mode & S_IFMT) { | |
1961 | case S_IFLNK: | |
1962 | goto out; | |
1963 | case S_IFREG: | |
1964 | /* NFSv4 has atomic_open... */ | |
1965 | if (nfs_server_capable(inode, NFS_CAP_ATOMIC_OPEN) | |
1966 | && nd != NULL | |
1967 | && (nd->flags & LOOKUP_OPEN)) | |
1968 | goto out; | |
1969 | break; | |
1970 | case S_IFDIR: | |
1971 | /* | |
1972 | * Optimize away all write operations, since the server | |
1973 | * will check permissions when we perform the op. | |
1974 | */ | |
1975 | if ((mask & MAY_WRITE) && !(mask & MAY_READ)) | |
1976 | goto out; | |
1977 | } | |
1978 | ||
1979 | force_lookup: | |
1980 | lock_kernel(); | |
1981 | ||
1982 | if (!NFS_PROTO(inode)->access) | |
1983 | goto out_notsup; | |
1984 | ||
1985 | cred = rpcauth_lookupcred(NFS_CLIENT(inode)->cl_auth, 0); | |
1986 | if (!IS_ERR(cred)) { | |
1987 | res = nfs_do_access(inode, cred, mask); | |
1988 | put_rpccred(cred); | |
1989 | } else | |
1990 | res = PTR_ERR(cred); | |
1991 | unlock_kernel(); | |
1992 | out: | |
1e7cb3dc CL |
1993 | dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n", |
1994 | inode->i_sb->s_id, inode->i_ino, mask, res); | |
1da177e4 LT |
1995 | return res; |
1996 | out_notsup: | |
1997 | res = nfs_revalidate_inode(NFS_SERVER(inode), inode); | |
1998 | if (res == 0) | |
1999 | res = generic_permission(inode, mask, NULL); | |
2000 | unlock_kernel(); | |
1e7cb3dc | 2001 | goto out; |
1da177e4 LT |
2002 | } |
2003 | ||
2004 | /* | |
2005 | * Local variables: | |
2006 | * version-control: t | |
2007 | * kept-new-versions: 5 | |
2008 | * End: | |
2009 | */ |