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1 | /* | |
2 | FUSE: Filesystem in Userspace | |
3 | Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu> | |
4 | ||
5 | This program can be distributed under the terms of the GNU GPL. | |
6 | See the file COPYING. | |
7 | */ | |
8 | ||
9 | #include "fuse_i.h" | |
10 | ||
11 | #include <linux/pagemap.h> | |
12 | #include <linux/file.h> | |
13 | #include <linux/sched.h> | |
14 | #include <linux/namei.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/xattr.h> | |
17 | #include <linux/iversion.h> | |
18 | #include <linux/posix_acl.h> | |
19 | ||
20 | static void fuse_advise_use_readdirplus(struct inode *dir) | |
21 | { | |
22 | struct fuse_inode *fi = get_fuse_inode(dir); | |
23 | ||
24 | set_bit(FUSE_I_ADVISE_RDPLUS, &fi->state); | |
25 | } | |
26 | ||
27 | #if BITS_PER_LONG >= 64 | |
28 | static inline void __fuse_dentry_settime(struct dentry *entry, u64 time) | |
29 | { | |
30 | entry->d_fsdata = (void *) time; | |
31 | } | |
32 | ||
33 | static inline u64 fuse_dentry_time(const struct dentry *entry) | |
34 | { | |
35 | return (u64)entry->d_fsdata; | |
36 | } | |
37 | ||
38 | #else | |
39 | union fuse_dentry { | |
40 | u64 time; | |
41 | struct rcu_head rcu; | |
42 | }; | |
43 | ||
44 | static inline void __fuse_dentry_settime(struct dentry *dentry, u64 time) | |
45 | { | |
46 | ((union fuse_dentry *) dentry->d_fsdata)->time = time; | |
47 | } | |
48 | ||
49 | static inline u64 fuse_dentry_time(const struct dentry *entry) | |
50 | { | |
51 | return ((union fuse_dentry *) entry->d_fsdata)->time; | |
52 | } | |
53 | #endif | |
54 | ||
55 | static void fuse_dentry_settime(struct dentry *dentry, u64 time) | |
56 | { | |
57 | struct fuse_conn *fc = get_fuse_conn_super(dentry->d_sb); | |
58 | bool delete = !time && fc->delete_stale; | |
59 | /* | |
60 | * Mess with DCACHE_OP_DELETE because dput() will be faster without it. | |
61 | * Don't care about races, either way it's just an optimization | |
62 | */ | |
63 | if ((!delete && (dentry->d_flags & DCACHE_OP_DELETE)) || | |
64 | (delete && !(dentry->d_flags & DCACHE_OP_DELETE))) { | |
65 | spin_lock(&dentry->d_lock); | |
66 | if (!delete) | |
67 | dentry->d_flags &= ~DCACHE_OP_DELETE; | |
68 | else | |
69 | dentry->d_flags |= DCACHE_OP_DELETE; | |
70 | spin_unlock(&dentry->d_lock); | |
71 | } | |
72 | ||
73 | __fuse_dentry_settime(dentry, time); | |
74 | } | |
75 | ||
76 | /* | |
77 | * FUSE caches dentries and attributes with separate timeout. The | |
78 | * time in jiffies until the dentry/attributes are valid is stored in | |
79 | * dentry->d_fsdata and fuse_inode->i_time respectively. | |
80 | */ | |
81 | ||
82 | /* | |
83 | * Calculate the time in jiffies until a dentry/attributes are valid | |
84 | */ | |
85 | static u64 time_to_jiffies(u64 sec, u32 nsec) | |
86 | { | |
87 | if (sec || nsec) { | |
88 | struct timespec64 ts = { | |
89 | sec, | |
90 | min_t(u32, nsec, NSEC_PER_SEC - 1) | |
91 | }; | |
92 | ||
93 | return get_jiffies_64() + timespec64_to_jiffies(&ts); | |
94 | } else | |
95 | return 0; | |
96 | } | |
97 | ||
98 | /* | |
99 | * Set dentry and possibly attribute timeouts from the lookup/mk* | |
100 | * replies | |
101 | */ | |
102 | void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o) | |
103 | { | |
104 | fuse_dentry_settime(entry, | |
105 | time_to_jiffies(o->entry_valid, o->entry_valid_nsec)); | |
106 | } | |
107 | ||
108 | static u64 attr_timeout(struct fuse_attr_out *o) | |
109 | { | |
110 | return time_to_jiffies(o->attr_valid, o->attr_valid_nsec); | |
111 | } | |
112 | ||
113 | u64 entry_attr_timeout(struct fuse_entry_out *o) | |
114 | { | |
115 | return time_to_jiffies(o->attr_valid, o->attr_valid_nsec); | |
116 | } | |
117 | ||
118 | static void fuse_invalidate_attr_mask(struct inode *inode, u32 mask) | |
119 | { | |
120 | set_mask_bits(&get_fuse_inode(inode)->inval_mask, 0, mask); | |
121 | } | |
122 | ||
123 | /* | |
124 | * Mark the attributes as stale, so that at the next call to | |
125 | * ->getattr() they will be fetched from userspace | |
126 | */ | |
127 | void fuse_invalidate_attr(struct inode *inode) | |
128 | { | |
129 | fuse_invalidate_attr_mask(inode, STATX_BASIC_STATS); | |
130 | } | |
131 | ||
132 | static void fuse_dir_changed(struct inode *dir) | |
133 | { | |
134 | fuse_invalidate_attr(dir); | |
135 | inode_maybe_inc_iversion(dir, false); | |
136 | } | |
137 | ||
138 | /** | |
139 | * Mark the attributes as stale due to an atime change. Avoid the invalidate if | |
140 | * atime is not used. | |
141 | */ | |
142 | void fuse_invalidate_atime(struct inode *inode) | |
143 | { | |
144 | if (!IS_RDONLY(inode)) | |
145 | fuse_invalidate_attr_mask(inode, STATX_ATIME); | |
146 | } | |
147 | ||
148 | /* | |
149 | * Just mark the entry as stale, so that a next attempt to look it up | |
150 | * will result in a new lookup call to userspace | |
151 | * | |
152 | * This is called when a dentry is about to become negative and the | |
153 | * timeout is unknown (unlink, rmdir, rename and in some cases | |
154 | * lookup) | |
155 | */ | |
156 | void fuse_invalidate_entry_cache(struct dentry *entry) | |
157 | { | |
158 | fuse_dentry_settime(entry, 0); | |
159 | } | |
160 | ||
161 | /* | |
162 | * Same as fuse_invalidate_entry_cache(), but also try to remove the | |
163 | * dentry from the hash | |
164 | */ | |
165 | static void fuse_invalidate_entry(struct dentry *entry) | |
166 | { | |
167 | d_invalidate(entry); | |
168 | fuse_invalidate_entry_cache(entry); | |
169 | } | |
170 | ||
171 | static void fuse_lookup_init(struct fuse_conn *fc, struct fuse_args *args, | |
172 | u64 nodeid, const struct qstr *name, | |
173 | struct fuse_entry_out *outarg) | |
174 | { | |
175 | memset(outarg, 0, sizeof(struct fuse_entry_out)); | |
176 | args->opcode = FUSE_LOOKUP; | |
177 | args->nodeid = nodeid; | |
178 | args->in_numargs = 1; | |
179 | args->in_args[0].size = name->len + 1; | |
180 | args->in_args[0].value = name->name; | |
181 | args->out_numargs = 1; | |
182 | args->out_args[0].size = sizeof(struct fuse_entry_out); | |
183 | args->out_args[0].value = outarg; | |
184 | } | |
185 | ||
186 | /* | |
187 | * Check whether the dentry is still valid | |
188 | * | |
189 | * If the entry validity timeout has expired and the dentry is | |
190 | * positive, try to redo the lookup. If the lookup results in a | |
191 | * different inode, then let the VFS invalidate the dentry and redo | |
192 | * the lookup once more. If the lookup results in the same inode, | |
193 | * then refresh the attributes, timeouts and mark the dentry valid. | |
194 | */ | |
195 | static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags) | |
196 | { | |
197 | struct inode *inode; | |
198 | struct dentry *parent; | |
199 | struct fuse_conn *fc; | |
200 | struct fuse_inode *fi; | |
201 | int ret; | |
202 | ||
203 | inode = d_inode_rcu(entry); | |
204 | if (inode && fuse_is_bad(inode)) | |
205 | goto invalid; | |
206 | else if (time_before64(fuse_dentry_time(entry), get_jiffies_64()) || | |
207 | (flags & LOOKUP_REVAL)) { | |
208 | struct fuse_entry_out outarg; | |
209 | FUSE_ARGS(args); | |
210 | struct fuse_forget_link *forget; | |
211 | u64 attr_version; | |
212 | ||
213 | /* For negative dentries, always do a fresh lookup */ | |
214 | if (!inode) | |
215 | goto invalid; | |
216 | ||
217 | ret = -ECHILD; | |
218 | if (flags & LOOKUP_RCU) | |
219 | goto out; | |
220 | ||
221 | fc = get_fuse_conn(inode); | |
222 | ||
223 | forget = fuse_alloc_forget(); | |
224 | ret = -ENOMEM; | |
225 | if (!forget) | |
226 | goto out; | |
227 | ||
228 | attr_version = fuse_get_attr_version(fc); | |
229 | ||
230 | parent = dget_parent(entry); | |
231 | fuse_lookup_init(fc, &args, get_node_id(d_inode(parent)), | |
232 | &entry->d_name, &outarg); | |
233 | ret = fuse_simple_request(fc, &args); | |
234 | dput(parent); | |
235 | /* Zero nodeid is same as -ENOENT */ | |
236 | if (!ret && !outarg.nodeid) | |
237 | ret = -ENOENT; | |
238 | if (!ret) { | |
239 | fi = get_fuse_inode(inode); | |
240 | if (outarg.nodeid != get_node_id(inode)) { | |
241 | fuse_queue_forget(fc, forget, outarg.nodeid, 1); | |
242 | goto invalid; | |
243 | } | |
244 | spin_lock(&fi->lock); | |
245 | fi->nlookup++; | |
246 | spin_unlock(&fi->lock); | |
247 | } | |
248 | kfree(forget); | |
249 | if (ret == -ENOMEM) | |
250 | goto out; | |
251 | if (ret || fuse_invalid_attr(&outarg.attr) || | |
252 | (outarg.attr.mode ^ inode->i_mode) & S_IFMT) | |
253 | goto invalid; | |
254 | ||
255 | forget_all_cached_acls(inode); | |
256 | fuse_change_attributes(inode, &outarg.attr, | |
257 | entry_attr_timeout(&outarg), | |
258 | attr_version); | |
259 | fuse_change_entry_timeout(entry, &outarg); | |
260 | } else if (inode) { | |
261 | fi = get_fuse_inode(inode); | |
262 | if (flags & LOOKUP_RCU) { | |
263 | if (test_bit(FUSE_I_INIT_RDPLUS, &fi->state)) | |
264 | return -ECHILD; | |
265 | } else if (test_and_clear_bit(FUSE_I_INIT_RDPLUS, &fi->state)) { | |
266 | parent = dget_parent(entry); | |
267 | fuse_advise_use_readdirplus(d_inode(parent)); | |
268 | dput(parent); | |
269 | } | |
270 | } | |
271 | ret = 1; | |
272 | out: | |
273 | return ret; | |
274 | ||
275 | invalid: | |
276 | ret = 0; | |
277 | goto out; | |
278 | } | |
279 | ||
280 | #if BITS_PER_LONG < 64 | |
281 | static int fuse_dentry_init(struct dentry *dentry) | |
282 | { | |
283 | dentry->d_fsdata = kzalloc(sizeof(union fuse_dentry), | |
284 | GFP_KERNEL_ACCOUNT | __GFP_RECLAIMABLE); | |
285 | ||
286 | return dentry->d_fsdata ? 0 : -ENOMEM; | |
287 | } | |
288 | static void fuse_dentry_release(struct dentry *dentry) | |
289 | { | |
290 | union fuse_dentry *fd = dentry->d_fsdata; | |
291 | ||
292 | kfree_rcu(fd, rcu); | |
293 | } | |
294 | #endif | |
295 | ||
296 | static int fuse_dentry_delete(const struct dentry *dentry) | |
297 | { | |
298 | return time_before64(fuse_dentry_time(dentry), get_jiffies_64()); | |
299 | } | |
300 | ||
301 | const struct dentry_operations fuse_dentry_operations = { | |
302 | .d_revalidate = fuse_dentry_revalidate, | |
303 | .d_delete = fuse_dentry_delete, | |
304 | #if BITS_PER_LONG < 64 | |
305 | .d_init = fuse_dentry_init, | |
306 | .d_release = fuse_dentry_release, | |
307 | #endif | |
308 | }; | |
309 | ||
310 | const struct dentry_operations fuse_root_dentry_operations = { | |
311 | #if BITS_PER_LONG < 64 | |
312 | .d_init = fuse_dentry_init, | |
313 | .d_release = fuse_dentry_release, | |
314 | #endif | |
315 | }; | |
316 | ||
317 | int fuse_valid_type(int m) | |
318 | { | |
319 | return S_ISREG(m) || S_ISDIR(m) || S_ISLNK(m) || S_ISCHR(m) || | |
320 | S_ISBLK(m) || S_ISFIFO(m) || S_ISSOCK(m); | |
321 | } | |
322 | ||
323 | bool fuse_invalid_attr(struct fuse_attr *attr) | |
324 | { | |
325 | return !fuse_valid_type(attr->mode) || | |
326 | attr->size > LLONG_MAX; | |
327 | } | |
328 | ||
329 | int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name, | |
330 | struct fuse_entry_out *outarg, struct inode **inode) | |
331 | { | |
332 | struct fuse_conn *fc = get_fuse_conn_super(sb); | |
333 | FUSE_ARGS(args); | |
334 | struct fuse_forget_link *forget; | |
335 | u64 attr_version; | |
336 | int err; | |
337 | ||
338 | *inode = NULL; | |
339 | err = -ENAMETOOLONG; | |
340 | if (name->len > FUSE_NAME_MAX) | |
341 | goto out; | |
342 | ||
343 | ||
344 | forget = fuse_alloc_forget(); | |
345 | err = -ENOMEM; | |
346 | if (!forget) | |
347 | goto out; | |
348 | ||
349 | attr_version = fuse_get_attr_version(fc); | |
350 | ||
351 | fuse_lookup_init(fc, &args, nodeid, name, outarg); | |
352 | err = fuse_simple_request(fc, &args); | |
353 | /* Zero nodeid is same as -ENOENT, but with valid timeout */ | |
354 | if (err || !outarg->nodeid) | |
355 | goto out_put_forget; | |
356 | ||
357 | err = -EIO; | |
358 | if (!outarg->nodeid) | |
359 | goto out_put_forget; | |
360 | if (fuse_invalid_attr(&outarg->attr)) | |
361 | goto out_put_forget; | |
362 | ||
363 | *inode = fuse_iget(sb, outarg->nodeid, outarg->generation, | |
364 | &outarg->attr, entry_attr_timeout(outarg), | |
365 | attr_version); | |
366 | err = -ENOMEM; | |
367 | if (!*inode) { | |
368 | fuse_queue_forget(fc, forget, outarg->nodeid, 1); | |
369 | goto out; | |
370 | } | |
371 | err = 0; | |
372 | ||
373 | out_put_forget: | |
374 | kfree(forget); | |
375 | out: | |
376 | return err; | |
377 | } | |
378 | ||
379 | static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, | |
380 | unsigned int flags) | |
381 | { | |
382 | int err; | |
383 | struct fuse_entry_out outarg; | |
384 | struct inode *inode; | |
385 | struct dentry *newent; | |
386 | bool outarg_valid = true; | |
387 | bool locked; | |
388 | ||
389 | if (fuse_is_bad(dir)) | |
390 | return ERR_PTR(-EIO); | |
391 | ||
392 | locked = fuse_lock_inode(dir); | |
393 | err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name, | |
394 | &outarg, &inode); | |
395 | fuse_unlock_inode(dir, locked); | |
396 | if (err == -ENOENT) { | |
397 | outarg_valid = false; | |
398 | err = 0; | |
399 | } | |
400 | if (err) | |
401 | goto out_err; | |
402 | ||
403 | err = -EIO; | |
404 | if (inode && get_node_id(inode) == FUSE_ROOT_ID) | |
405 | goto out_iput; | |
406 | ||
407 | newent = d_splice_alias(inode, entry); | |
408 | err = PTR_ERR(newent); | |
409 | if (IS_ERR(newent)) | |
410 | goto out_err; | |
411 | ||
412 | entry = newent ? newent : entry; | |
413 | if (outarg_valid) | |
414 | fuse_change_entry_timeout(entry, &outarg); | |
415 | else | |
416 | fuse_invalidate_entry_cache(entry); | |
417 | ||
418 | if (inode) | |
419 | fuse_advise_use_readdirplus(dir); | |
420 | return newent; | |
421 | ||
422 | out_iput: | |
423 | iput(inode); | |
424 | out_err: | |
425 | return ERR_PTR(err); | |
426 | } | |
427 | ||
428 | /* | |
429 | * Atomic create+open operation | |
430 | * | |
431 | * If the filesystem doesn't support this, then fall back to separate | |
432 | * 'mknod' + 'open' requests. | |
433 | */ | |
434 | static int fuse_create_open(struct inode *dir, struct dentry *entry, | |
435 | struct file *file, unsigned flags, | |
436 | umode_t mode) | |
437 | { | |
438 | int err; | |
439 | struct inode *inode; | |
440 | struct fuse_conn *fc = get_fuse_conn(dir); | |
441 | FUSE_ARGS(args); | |
442 | struct fuse_forget_link *forget; | |
443 | struct fuse_create_in inarg; | |
444 | struct fuse_open_out outopen; | |
445 | struct fuse_entry_out outentry; | |
446 | struct fuse_inode *fi; | |
447 | struct fuse_file *ff; | |
448 | ||
449 | /* Userspace expects S_IFREG in create mode */ | |
450 | BUG_ON((mode & S_IFMT) != S_IFREG); | |
451 | ||
452 | forget = fuse_alloc_forget(); | |
453 | err = -ENOMEM; | |
454 | if (!forget) | |
455 | goto out_err; | |
456 | ||
457 | err = -ENOMEM; | |
458 | ff = fuse_file_alloc(fc); | |
459 | if (!ff) | |
460 | goto out_put_forget_req; | |
461 | ||
462 | if (!fc->dont_mask) | |
463 | mode &= ~current_umask(); | |
464 | ||
465 | flags &= ~O_NOCTTY; | |
466 | memset(&inarg, 0, sizeof(inarg)); | |
467 | memset(&outentry, 0, sizeof(outentry)); | |
468 | inarg.flags = flags; | |
469 | inarg.mode = mode; | |
470 | inarg.umask = current_umask(); | |
471 | args.opcode = FUSE_CREATE; | |
472 | args.nodeid = get_node_id(dir); | |
473 | args.in_numargs = 2; | |
474 | args.in_args[0].size = sizeof(inarg); | |
475 | args.in_args[0].value = &inarg; | |
476 | args.in_args[1].size = entry->d_name.len + 1; | |
477 | args.in_args[1].value = entry->d_name.name; | |
478 | args.out_numargs = 2; | |
479 | args.out_args[0].size = sizeof(outentry); | |
480 | args.out_args[0].value = &outentry; | |
481 | args.out_args[1].size = sizeof(outopen); | |
482 | args.out_args[1].value = &outopen; | |
483 | err = fuse_simple_request(fc, &args); | |
484 | if (err) | |
485 | goto out_free_ff; | |
486 | ||
487 | err = -EIO; | |
488 | if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid) || | |
489 | fuse_invalid_attr(&outentry.attr)) | |
490 | goto out_free_ff; | |
491 | ||
492 | ff->fh = outopen.fh; | |
493 | ff->nodeid = outentry.nodeid; | |
494 | ff->open_flags = outopen.open_flags; | |
495 | inode = fuse_iget(dir->i_sb, outentry.nodeid, outentry.generation, | |
496 | &outentry.attr, entry_attr_timeout(&outentry), 0); | |
497 | if (!inode) { | |
498 | flags &= ~(O_CREAT | O_EXCL | O_TRUNC); | |
499 | fuse_sync_release(NULL, ff, flags); | |
500 | fuse_queue_forget(fc, forget, outentry.nodeid, 1); | |
501 | err = -ENOMEM; | |
502 | goto out_err; | |
503 | } | |
504 | kfree(forget); | |
505 | d_instantiate(entry, inode); | |
506 | fuse_change_entry_timeout(entry, &outentry); | |
507 | fuse_dir_changed(dir); | |
508 | err = finish_open(file, entry, generic_file_open); | |
509 | if (err) { | |
510 | fi = get_fuse_inode(inode); | |
511 | fuse_sync_release(fi, ff, flags); | |
512 | } else { | |
513 | file->private_data = ff; | |
514 | fuse_finish_open(inode, file); | |
515 | } | |
516 | return err; | |
517 | ||
518 | out_free_ff: | |
519 | fuse_file_free(ff); | |
520 | out_put_forget_req: | |
521 | kfree(forget); | |
522 | out_err: | |
523 | return err; | |
524 | } | |
525 | ||
526 | static int fuse_mknod(struct inode *, struct dentry *, umode_t, dev_t); | |
527 | static int fuse_atomic_open(struct inode *dir, struct dentry *entry, | |
528 | struct file *file, unsigned flags, | |
529 | umode_t mode) | |
530 | { | |
531 | int err; | |
532 | struct fuse_conn *fc = get_fuse_conn(dir); | |
533 | struct dentry *res = NULL; | |
534 | ||
535 | if (fuse_is_bad(dir)) | |
536 | return -EIO; | |
537 | ||
538 | if (d_in_lookup(entry)) { | |
539 | res = fuse_lookup(dir, entry, 0); | |
540 | if (IS_ERR(res)) | |
541 | return PTR_ERR(res); | |
542 | ||
543 | if (res) | |
544 | entry = res; | |
545 | } | |
546 | ||
547 | if (!(flags & O_CREAT) || d_really_is_positive(entry)) | |
548 | goto no_open; | |
549 | ||
550 | /* Only creates */ | |
551 | file->f_mode |= FMODE_CREATED; | |
552 | ||
553 | if (fc->no_create) | |
554 | goto mknod; | |
555 | ||
556 | err = fuse_create_open(dir, entry, file, flags, mode); | |
557 | if (err == -ENOSYS) { | |
558 | fc->no_create = 1; | |
559 | goto mknod; | |
560 | } | |
561 | out_dput: | |
562 | dput(res); | |
563 | return err; | |
564 | ||
565 | mknod: | |
566 | err = fuse_mknod(dir, entry, mode, 0); | |
567 | if (err) | |
568 | goto out_dput; | |
569 | no_open: | |
570 | return finish_no_open(file, res); | |
571 | } | |
572 | ||
573 | /* | |
574 | * Code shared between mknod, mkdir, symlink and link | |
575 | */ | |
576 | static int create_new_entry(struct fuse_conn *fc, struct fuse_args *args, | |
577 | struct inode *dir, struct dentry *entry, | |
578 | umode_t mode) | |
579 | { | |
580 | struct fuse_entry_out outarg; | |
581 | struct inode *inode; | |
582 | struct dentry *d; | |
583 | int err; | |
584 | struct fuse_forget_link *forget; | |
585 | ||
586 | if (fuse_is_bad(dir)) | |
587 | return -EIO; | |
588 | ||
589 | forget = fuse_alloc_forget(); | |
590 | if (!forget) | |
591 | return -ENOMEM; | |
592 | ||
593 | memset(&outarg, 0, sizeof(outarg)); | |
594 | args->nodeid = get_node_id(dir); | |
595 | args->out_numargs = 1; | |
596 | args->out_args[0].size = sizeof(outarg); | |
597 | args->out_args[0].value = &outarg; | |
598 | err = fuse_simple_request(fc, args); | |
599 | if (err) | |
600 | goto out_put_forget_req; | |
601 | ||
602 | err = -EIO; | |
603 | if (invalid_nodeid(outarg.nodeid) || fuse_invalid_attr(&outarg.attr)) | |
604 | goto out_put_forget_req; | |
605 | ||
606 | if ((outarg.attr.mode ^ mode) & S_IFMT) | |
607 | goto out_put_forget_req; | |
608 | ||
609 | inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation, | |
610 | &outarg.attr, entry_attr_timeout(&outarg), 0); | |
611 | if (!inode) { | |
612 | fuse_queue_forget(fc, forget, outarg.nodeid, 1); | |
613 | return -ENOMEM; | |
614 | } | |
615 | kfree(forget); | |
616 | ||
617 | d_drop(entry); | |
618 | d = d_splice_alias(inode, entry); | |
619 | if (IS_ERR(d)) | |
620 | return PTR_ERR(d); | |
621 | ||
622 | if (d) { | |
623 | fuse_change_entry_timeout(d, &outarg); | |
624 | dput(d); | |
625 | } else { | |
626 | fuse_change_entry_timeout(entry, &outarg); | |
627 | } | |
628 | fuse_dir_changed(dir); | |
629 | return 0; | |
630 | ||
631 | out_put_forget_req: | |
632 | kfree(forget); | |
633 | return err; | |
634 | } | |
635 | ||
636 | static int fuse_mknod(struct inode *dir, struct dentry *entry, umode_t mode, | |
637 | dev_t rdev) | |
638 | { | |
639 | struct fuse_mknod_in inarg; | |
640 | struct fuse_conn *fc = get_fuse_conn(dir); | |
641 | FUSE_ARGS(args); | |
642 | ||
643 | if (!fc->dont_mask) | |
644 | mode &= ~current_umask(); | |
645 | ||
646 | memset(&inarg, 0, sizeof(inarg)); | |
647 | inarg.mode = mode; | |
648 | inarg.rdev = new_encode_dev(rdev); | |
649 | inarg.umask = current_umask(); | |
650 | args.opcode = FUSE_MKNOD; | |
651 | args.in_numargs = 2; | |
652 | args.in_args[0].size = sizeof(inarg); | |
653 | args.in_args[0].value = &inarg; | |
654 | args.in_args[1].size = entry->d_name.len + 1; | |
655 | args.in_args[1].value = entry->d_name.name; | |
656 | return create_new_entry(fc, &args, dir, entry, mode); | |
657 | } | |
658 | ||
659 | static int fuse_create(struct inode *dir, struct dentry *entry, umode_t mode, | |
660 | bool excl) | |
661 | { | |
662 | return fuse_mknod(dir, entry, mode, 0); | |
663 | } | |
664 | ||
665 | static int fuse_mkdir(struct inode *dir, struct dentry *entry, umode_t mode) | |
666 | { | |
667 | struct fuse_mkdir_in inarg; | |
668 | struct fuse_conn *fc = get_fuse_conn(dir); | |
669 | FUSE_ARGS(args); | |
670 | ||
671 | if (!fc->dont_mask) | |
672 | mode &= ~current_umask(); | |
673 | ||
674 | memset(&inarg, 0, sizeof(inarg)); | |
675 | inarg.mode = mode; | |
676 | inarg.umask = current_umask(); | |
677 | args.opcode = FUSE_MKDIR; | |
678 | args.in_numargs = 2; | |
679 | args.in_args[0].size = sizeof(inarg); | |
680 | args.in_args[0].value = &inarg; | |
681 | args.in_args[1].size = entry->d_name.len + 1; | |
682 | args.in_args[1].value = entry->d_name.name; | |
683 | return create_new_entry(fc, &args, dir, entry, S_IFDIR); | |
684 | } | |
685 | ||
686 | static int fuse_symlink(struct inode *dir, struct dentry *entry, | |
687 | const char *link) | |
688 | { | |
689 | struct fuse_conn *fc = get_fuse_conn(dir); | |
690 | unsigned len = strlen(link) + 1; | |
691 | FUSE_ARGS(args); | |
692 | ||
693 | args.opcode = FUSE_SYMLINK; | |
694 | args.in_numargs = 2; | |
695 | args.in_args[0].size = entry->d_name.len + 1; | |
696 | args.in_args[0].value = entry->d_name.name; | |
697 | args.in_args[1].size = len; | |
698 | args.in_args[1].value = link; | |
699 | return create_new_entry(fc, &args, dir, entry, S_IFLNK); | |
700 | } | |
701 | ||
702 | void fuse_update_ctime(struct inode *inode) | |
703 | { | |
704 | if (!IS_NOCMTIME(inode)) { | |
705 | inode->i_ctime = current_time(inode); | |
706 | mark_inode_dirty_sync(inode); | |
707 | } | |
708 | } | |
709 | ||
710 | static int fuse_unlink(struct inode *dir, struct dentry *entry) | |
711 | { | |
712 | int err; | |
713 | struct fuse_conn *fc = get_fuse_conn(dir); | |
714 | FUSE_ARGS(args); | |
715 | ||
716 | if (fuse_is_bad(dir)) | |
717 | return -EIO; | |
718 | ||
719 | args.opcode = FUSE_UNLINK; | |
720 | args.nodeid = get_node_id(dir); | |
721 | args.in_numargs = 1; | |
722 | args.in_args[0].size = entry->d_name.len + 1; | |
723 | args.in_args[0].value = entry->d_name.name; | |
724 | err = fuse_simple_request(fc, &args); | |
725 | if (!err) { | |
726 | struct inode *inode = d_inode(entry); | |
727 | struct fuse_inode *fi = get_fuse_inode(inode); | |
728 | ||
729 | spin_lock(&fi->lock); | |
730 | fi->attr_version = atomic64_inc_return(&fc->attr_version); | |
731 | /* | |
732 | * If i_nlink == 0 then unlink doesn't make sense, yet this can | |
733 | * happen if userspace filesystem is careless. It would be | |
734 | * difficult to enforce correct nlink usage so just ignore this | |
735 | * condition here | |
736 | */ | |
737 | if (inode->i_nlink > 0) | |
738 | drop_nlink(inode); | |
739 | spin_unlock(&fi->lock); | |
740 | fuse_invalidate_attr(inode); | |
741 | fuse_dir_changed(dir); | |
742 | fuse_invalidate_entry_cache(entry); | |
743 | fuse_update_ctime(inode); | |
744 | } else if (err == -EINTR) | |
745 | fuse_invalidate_entry(entry); | |
746 | return err; | |
747 | } | |
748 | ||
749 | static int fuse_rmdir(struct inode *dir, struct dentry *entry) | |
750 | { | |
751 | int err; | |
752 | struct fuse_conn *fc = get_fuse_conn(dir); | |
753 | FUSE_ARGS(args); | |
754 | ||
755 | if (fuse_is_bad(dir)) | |
756 | return -EIO; | |
757 | ||
758 | args.opcode = FUSE_RMDIR; | |
759 | args.nodeid = get_node_id(dir); | |
760 | args.in_numargs = 1; | |
761 | args.in_args[0].size = entry->d_name.len + 1; | |
762 | args.in_args[0].value = entry->d_name.name; | |
763 | err = fuse_simple_request(fc, &args); | |
764 | if (!err) { | |
765 | clear_nlink(d_inode(entry)); | |
766 | fuse_dir_changed(dir); | |
767 | fuse_invalidate_entry_cache(entry); | |
768 | } else if (err == -EINTR) | |
769 | fuse_invalidate_entry(entry); | |
770 | return err; | |
771 | } | |
772 | ||
773 | static int fuse_rename_common(struct inode *olddir, struct dentry *oldent, | |
774 | struct inode *newdir, struct dentry *newent, | |
775 | unsigned int flags, int opcode, size_t argsize) | |
776 | { | |
777 | int err; | |
778 | struct fuse_rename2_in inarg; | |
779 | struct fuse_conn *fc = get_fuse_conn(olddir); | |
780 | FUSE_ARGS(args); | |
781 | ||
782 | memset(&inarg, 0, argsize); | |
783 | inarg.newdir = get_node_id(newdir); | |
784 | inarg.flags = flags; | |
785 | args.opcode = opcode; | |
786 | args.nodeid = get_node_id(olddir); | |
787 | args.in_numargs = 3; | |
788 | args.in_args[0].size = argsize; | |
789 | args.in_args[0].value = &inarg; | |
790 | args.in_args[1].size = oldent->d_name.len + 1; | |
791 | args.in_args[1].value = oldent->d_name.name; | |
792 | args.in_args[2].size = newent->d_name.len + 1; | |
793 | args.in_args[2].value = newent->d_name.name; | |
794 | err = fuse_simple_request(fc, &args); | |
795 | if (!err) { | |
796 | /* ctime changes */ | |
797 | fuse_invalidate_attr(d_inode(oldent)); | |
798 | fuse_update_ctime(d_inode(oldent)); | |
799 | ||
800 | if (flags & RENAME_EXCHANGE) { | |
801 | fuse_invalidate_attr(d_inode(newent)); | |
802 | fuse_update_ctime(d_inode(newent)); | |
803 | } | |
804 | ||
805 | fuse_dir_changed(olddir); | |
806 | if (olddir != newdir) | |
807 | fuse_dir_changed(newdir); | |
808 | ||
809 | /* newent will end up negative */ | |
810 | if (!(flags & RENAME_EXCHANGE) && d_really_is_positive(newent)) { | |
811 | fuse_invalidate_attr(d_inode(newent)); | |
812 | fuse_invalidate_entry_cache(newent); | |
813 | fuse_update_ctime(d_inode(newent)); | |
814 | } | |
815 | } else if (err == -EINTR) { | |
816 | /* If request was interrupted, DEITY only knows if the | |
817 | rename actually took place. If the invalidation | |
818 | fails (e.g. some process has CWD under the renamed | |
819 | directory), then there can be inconsistency between | |
820 | the dcache and the real filesystem. Tough luck. */ | |
821 | fuse_invalidate_entry(oldent); | |
822 | if (d_really_is_positive(newent)) | |
823 | fuse_invalidate_entry(newent); | |
824 | } | |
825 | ||
826 | return err; | |
827 | } | |
828 | ||
829 | static int fuse_rename2(struct inode *olddir, struct dentry *oldent, | |
830 | struct inode *newdir, struct dentry *newent, | |
831 | unsigned int flags) | |
832 | { | |
833 | struct fuse_conn *fc = get_fuse_conn(olddir); | |
834 | int err; | |
835 | ||
836 | if (fuse_is_bad(olddir)) | |
837 | return -EIO; | |
838 | ||
839 | if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE)) | |
840 | return -EINVAL; | |
841 | ||
842 | if (flags) { | |
843 | if (fc->no_rename2 || fc->minor < 23) | |
844 | return -EINVAL; | |
845 | ||
846 | err = fuse_rename_common(olddir, oldent, newdir, newent, flags, | |
847 | FUSE_RENAME2, | |
848 | sizeof(struct fuse_rename2_in)); | |
849 | if (err == -ENOSYS) { | |
850 | fc->no_rename2 = 1; | |
851 | err = -EINVAL; | |
852 | } | |
853 | } else { | |
854 | err = fuse_rename_common(olddir, oldent, newdir, newent, 0, | |
855 | FUSE_RENAME, | |
856 | sizeof(struct fuse_rename_in)); | |
857 | } | |
858 | ||
859 | return err; | |
860 | } | |
861 | ||
862 | static int fuse_link(struct dentry *entry, struct inode *newdir, | |
863 | struct dentry *newent) | |
864 | { | |
865 | int err; | |
866 | struct fuse_link_in inarg; | |
867 | struct inode *inode = d_inode(entry); | |
868 | struct fuse_conn *fc = get_fuse_conn(inode); | |
869 | FUSE_ARGS(args); | |
870 | ||
871 | memset(&inarg, 0, sizeof(inarg)); | |
872 | inarg.oldnodeid = get_node_id(inode); | |
873 | args.opcode = FUSE_LINK; | |
874 | args.in_numargs = 2; | |
875 | args.in_args[0].size = sizeof(inarg); | |
876 | args.in_args[0].value = &inarg; | |
877 | args.in_args[1].size = newent->d_name.len + 1; | |
878 | args.in_args[1].value = newent->d_name.name; | |
879 | err = create_new_entry(fc, &args, newdir, newent, inode->i_mode); | |
880 | /* Contrary to "normal" filesystems it can happen that link | |
881 | makes two "logical" inodes point to the same "physical" | |
882 | inode. We invalidate the attributes of the old one, so it | |
883 | will reflect changes in the backing inode (link count, | |
884 | etc.) | |
885 | */ | |
886 | if (!err) { | |
887 | struct fuse_inode *fi = get_fuse_inode(inode); | |
888 | ||
889 | spin_lock(&fi->lock); | |
890 | fi->attr_version = atomic64_inc_return(&fc->attr_version); | |
891 | if (likely(inode->i_nlink < UINT_MAX)) | |
892 | inc_nlink(inode); | |
893 | spin_unlock(&fi->lock); | |
894 | fuse_invalidate_attr(inode); | |
895 | fuse_update_ctime(inode); | |
896 | } else if (err == -EINTR) { | |
897 | fuse_invalidate_attr(inode); | |
898 | } | |
899 | return err; | |
900 | } | |
901 | ||
902 | static void fuse_fillattr(struct inode *inode, struct fuse_attr *attr, | |
903 | struct kstat *stat) | |
904 | { | |
905 | unsigned int blkbits; | |
906 | struct fuse_conn *fc = get_fuse_conn(inode); | |
907 | ||
908 | /* see the comment in fuse_change_attributes() */ | |
909 | if (fc->writeback_cache && S_ISREG(inode->i_mode)) { | |
910 | attr->size = i_size_read(inode); | |
911 | attr->mtime = inode->i_mtime.tv_sec; | |
912 | attr->mtimensec = inode->i_mtime.tv_nsec; | |
913 | attr->ctime = inode->i_ctime.tv_sec; | |
914 | attr->ctimensec = inode->i_ctime.tv_nsec; | |
915 | } | |
916 | ||
917 | stat->dev = inode->i_sb->s_dev; | |
918 | stat->ino = attr->ino; | |
919 | stat->mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777); | |
920 | stat->nlink = attr->nlink; | |
921 | stat->uid = make_kuid(fc->user_ns, attr->uid); | |
922 | stat->gid = make_kgid(fc->user_ns, attr->gid); | |
923 | stat->rdev = inode->i_rdev; | |
924 | stat->atime.tv_sec = attr->atime; | |
925 | stat->atime.tv_nsec = attr->atimensec; | |
926 | stat->mtime.tv_sec = attr->mtime; | |
927 | stat->mtime.tv_nsec = attr->mtimensec; | |
928 | stat->ctime.tv_sec = attr->ctime; | |
929 | stat->ctime.tv_nsec = attr->ctimensec; | |
930 | stat->size = attr->size; | |
931 | stat->blocks = attr->blocks; | |
932 | ||
933 | if (attr->blksize != 0) | |
934 | blkbits = ilog2(attr->blksize); | |
935 | else | |
936 | blkbits = inode->i_sb->s_blocksize_bits; | |
937 | ||
938 | stat->blksize = 1 << blkbits; | |
939 | } | |
940 | ||
941 | static int fuse_do_getattr(struct inode *inode, struct kstat *stat, | |
942 | struct file *file) | |
943 | { | |
944 | int err; | |
945 | struct fuse_getattr_in inarg; | |
946 | struct fuse_attr_out outarg; | |
947 | struct fuse_conn *fc = get_fuse_conn(inode); | |
948 | FUSE_ARGS(args); | |
949 | u64 attr_version; | |
950 | ||
951 | attr_version = fuse_get_attr_version(fc); | |
952 | ||
953 | memset(&inarg, 0, sizeof(inarg)); | |
954 | memset(&outarg, 0, sizeof(outarg)); | |
955 | /* Directories have separate file-handle space */ | |
956 | if (file && S_ISREG(inode->i_mode)) { | |
957 | struct fuse_file *ff = file->private_data; | |
958 | ||
959 | inarg.getattr_flags |= FUSE_GETATTR_FH; | |
960 | inarg.fh = ff->fh; | |
961 | } | |
962 | args.opcode = FUSE_GETATTR; | |
963 | args.nodeid = get_node_id(inode); | |
964 | args.in_numargs = 1; | |
965 | args.in_args[0].size = sizeof(inarg); | |
966 | args.in_args[0].value = &inarg; | |
967 | args.out_numargs = 1; | |
968 | args.out_args[0].size = sizeof(outarg); | |
969 | args.out_args[0].value = &outarg; | |
970 | err = fuse_simple_request(fc, &args); | |
971 | if (!err) { | |
972 | if (fuse_invalid_attr(&outarg.attr) || | |
973 | (inode->i_mode ^ outarg.attr.mode) & S_IFMT) { | |
974 | fuse_make_bad(inode); | |
975 | err = -EIO; | |
976 | } else { | |
977 | fuse_change_attributes(inode, &outarg.attr, | |
978 | attr_timeout(&outarg), | |
979 | attr_version); | |
980 | if (stat) | |
981 | fuse_fillattr(inode, &outarg.attr, stat); | |
982 | } | |
983 | } | |
984 | return err; | |
985 | } | |
986 | ||
987 | static int fuse_update_get_attr(struct inode *inode, struct file *file, | |
988 | struct kstat *stat, u32 request_mask, | |
989 | unsigned int flags) | |
990 | { | |
991 | struct fuse_inode *fi = get_fuse_inode(inode); | |
992 | int err = 0; | |
993 | bool sync; | |
994 | ||
995 | if (flags & AT_STATX_FORCE_SYNC) | |
996 | sync = true; | |
997 | else if (flags & AT_STATX_DONT_SYNC) | |
998 | sync = false; | |
999 | else if (request_mask & READ_ONCE(fi->inval_mask)) | |
1000 | sync = true; | |
1001 | else | |
1002 | sync = time_before64(fi->i_time, get_jiffies_64()); | |
1003 | ||
1004 | if (sync) { | |
1005 | forget_all_cached_acls(inode); | |
1006 | err = fuse_do_getattr(inode, stat, file); | |
1007 | } else if (stat) { | |
1008 | generic_fillattr(inode, stat); | |
1009 | stat->mode = fi->orig_i_mode; | |
1010 | stat->ino = fi->orig_ino; | |
1011 | } | |
1012 | ||
1013 | return err; | |
1014 | } | |
1015 | ||
1016 | int fuse_update_attributes(struct inode *inode, struct file *file) | |
1017 | { | |
1018 | /* Do *not* need to get atime for internal purposes */ | |
1019 | return fuse_update_get_attr(inode, file, NULL, | |
1020 | STATX_BASIC_STATS & ~STATX_ATIME, 0); | |
1021 | } | |
1022 | ||
1023 | int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid, | |
1024 | u64 child_nodeid, struct qstr *name) | |
1025 | { | |
1026 | int err = -ENOTDIR; | |
1027 | struct inode *parent; | |
1028 | struct dentry *dir; | |
1029 | struct dentry *entry; | |
1030 | ||
1031 | parent = ilookup5(sb, parent_nodeid, fuse_inode_eq, &parent_nodeid); | |
1032 | if (!parent) | |
1033 | return -ENOENT; | |
1034 | ||
1035 | inode_lock_nested(parent, I_MUTEX_PARENT); | |
1036 | if (!S_ISDIR(parent->i_mode)) | |
1037 | goto unlock; | |
1038 | ||
1039 | err = -ENOENT; | |
1040 | dir = d_find_alias(parent); | |
1041 | if (!dir) | |
1042 | goto unlock; | |
1043 | ||
1044 | name->hash = full_name_hash(dir, name->name, name->len); | |
1045 | entry = d_lookup(dir, name); | |
1046 | dput(dir); | |
1047 | if (!entry) | |
1048 | goto unlock; | |
1049 | ||
1050 | fuse_dir_changed(parent); | |
1051 | fuse_invalidate_entry(entry); | |
1052 | ||
1053 | if (child_nodeid != 0 && d_really_is_positive(entry)) { | |
1054 | inode_lock(d_inode(entry)); | |
1055 | if (get_node_id(d_inode(entry)) != child_nodeid) { | |
1056 | err = -ENOENT; | |
1057 | goto badentry; | |
1058 | } | |
1059 | if (d_mountpoint(entry)) { | |
1060 | err = -EBUSY; | |
1061 | goto badentry; | |
1062 | } | |
1063 | if (d_is_dir(entry)) { | |
1064 | shrink_dcache_parent(entry); | |
1065 | if (!simple_empty(entry)) { | |
1066 | err = -ENOTEMPTY; | |
1067 | goto badentry; | |
1068 | } | |
1069 | d_inode(entry)->i_flags |= S_DEAD; | |
1070 | } | |
1071 | dont_mount(entry); | |
1072 | clear_nlink(d_inode(entry)); | |
1073 | err = 0; | |
1074 | badentry: | |
1075 | inode_unlock(d_inode(entry)); | |
1076 | if (!err) | |
1077 | d_delete(entry); | |
1078 | } else { | |
1079 | err = 0; | |
1080 | } | |
1081 | dput(entry); | |
1082 | ||
1083 | unlock: | |
1084 | inode_unlock(parent); | |
1085 | iput(parent); | |
1086 | return err; | |
1087 | } | |
1088 | ||
1089 | /* | |
1090 | * Calling into a user-controlled filesystem gives the filesystem | |
1091 | * daemon ptrace-like capabilities over the current process. This | |
1092 | * means, that the filesystem daemon is able to record the exact | |
1093 | * filesystem operations performed, and can also control the behavior | |
1094 | * of the requester process in otherwise impossible ways. For example | |
1095 | * it can delay the operation for arbitrary length of time allowing | |
1096 | * DoS against the requester. | |
1097 | * | |
1098 | * For this reason only those processes can call into the filesystem, | |
1099 | * for which the owner of the mount has ptrace privilege. This | |
1100 | * excludes processes started by other users, suid or sgid processes. | |
1101 | */ | |
1102 | int fuse_allow_current_process(struct fuse_conn *fc) | |
1103 | { | |
1104 | const struct cred *cred; | |
1105 | ||
1106 | if (fc->allow_other) | |
1107 | return current_in_userns(fc->user_ns); | |
1108 | ||
1109 | cred = current_cred(); | |
1110 | if (uid_eq(cred->euid, fc->user_id) && | |
1111 | uid_eq(cred->suid, fc->user_id) && | |
1112 | uid_eq(cred->uid, fc->user_id) && | |
1113 | gid_eq(cred->egid, fc->group_id) && | |
1114 | gid_eq(cred->sgid, fc->group_id) && | |
1115 | gid_eq(cred->gid, fc->group_id)) | |
1116 | return 1; | |
1117 | ||
1118 | return 0; | |
1119 | } | |
1120 | ||
1121 | static int fuse_access(struct inode *inode, int mask) | |
1122 | { | |
1123 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1124 | FUSE_ARGS(args); | |
1125 | struct fuse_access_in inarg; | |
1126 | int err; | |
1127 | ||
1128 | BUG_ON(mask & MAY_NOT_BLOCK); | |
1129 | ||
1130 | if (fc->no_access) | |
1131 | return 0; | |
1132 | ||
1133 | memset(&inarg, 0, sizeof(inarg)); | |
1134 | inarg.mask = mask & (MAY_READ | MAY_WRITE | MAY_EXEC); | |
1135 | args.opcode = FUSE_ACCESS; | |
1136 | args.nodeid = get_node_id(inode); | |
1137 | args.in_numargs = 1; | |
1138 | args.in_args[0].size = sizeof(inarg); | |
1139 | args.in_args[0].value = &inarg; | |
1140 | err = fuse_simple_request(fc, &args); | |
1141 | if (err == -ENOSYS) { | |
1142 | fc->no_access = 1; | |
1143 | err = 0; | |
1144 | } | |
1145 | return err; | |
1146 | } | |
1147 | ||
1148 | static int fuse_perm_getattr(struct inode *inode, int mask) | |
1149 | { | |
1150 | if (mask & MAY_NOT_BLOCK) | |
1151 | return -ECHILD; | |
1152 | ||
1153 | forget_all_cached_acls(inode); | |
1154 | return fuse_do_getattr(inode, NULL, NULL); | |
1155 | } | |
1156 | ||
1157 | /* | |
1158 | * Check permission. The two basic access models of FUSE are: | |
1159 | * | |
1160 | * 1) Local access checking ('default_permissions' mount option) based | |
1161 | * on file mode. This is the plain old disk filesystem permission | |
1162 | * modell. | |
1163 | * | |
1164 | * 2) "Remote" access checking, where server is responsible for | |
1165 | * checking permission in each inode operation. An exception to this | |
1166 | * is if ->permission() was invoked from sys_access() in which case an | |
1167 | * access request is sent. Execute permission is still checked | |
1168 | * locally based on file mode. | |
1169 | */ | |
1170 | static int fuse_permission(struct inode *inode, int mask) | |
1171 | { | |
1172 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1173 | bool refreshed = false; | |
1174 | int err = 0; | |
1175 | ||
1176 | if (fuse_is_bad(inode)) | |
1177 | return -EIO; | |
1178 | ||
1179 | if (!fuse_allow_current_process(fc)) | |
1180 | return -EACCES; | |
1181 | ||
1182 | /* | |
1183 | * If attributes are needed, refresh them before proceeding | |
1184 | */ | |
1185 | if (fc->default_permissions || | |
1186 | ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))) { | |
1187 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1188 | u32 perm_mask = STATX_MODE | STATX_UID | STATX_GID; | |
1189 | ||
1190 | if (perm_mask & READ_ONCE(fi->inval_mask) || | |
1191 | time_before64(fi->i_time, get_jiffies_64())) { | |
1192 | refreshed = true; | |
1193 | ||
1194 | err = fuse_perm_getattr(inode, mask); | |
1195 | if (err) | |
1196 | return err; | |
1197 | } | |
1198 | } | |
1199 | ||
1200 | if (fc->default_permissions) { | |
1201 | err = generic_permission(inode, mask); | |
1202 | ||
1203 | /* If permission is denied, try to refresh file | |
1204 | attributes. This is also needed, because the root | |
1205 | node will at first have no permissions */ | |
1206 | if (err == -EACCES && !refreshed) { | |
1207 | err = fuse_perm_getattr(inode, mask); | |
1208 | if (!err) | |
1209 | err = generic_permission(inode, mask); | |
1210 | } | |
1211 | ||
1212 | /* Note: the opposite of the above test does not | |
1213 | exist. So if permissions are revoked this won't be | |
1214 | noticed immediately, only after the attribute | |
1215 | timeout has expired */ | |
1216 | } else if (mask & (MAY_ACCESS | MAY_CHDIR)) { | |
1217 | err = fuse_access(inode, mask); | |
1218 | } else if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) { | |
1219 | if (!(inode->i_mode & S_IXUGO)) { | |
1220 | if (refreshed) | |
1221 | return -EACCES; | |
1222 | ||
1223 | err = fuse_perm_getattr(inode, mask); | |
1224 | if (!err && !(inode->i_mode & S_IXUGO)) | |
1225 | return -EACCES; | |
1226 | } | |
1227 | } | |
1228 | return err; | |
1229 | } | |
1230 | ||
1231 | static int fuse_readlink_page(struct inode *inode, struct page *page) | |
1232 | { | |
1233 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1234 | struct fuse_page_desc desc = { .length = PAGE_SIZE - 1 }; | |
1235 | struct fuse_args_pages ap = { | |
1236 | .num_pages = 1, | |
1237 | .pages = &page, | |
1238 | .descs = &desc, | |
1239 | }; | |
1240 | char *link; | |
1241 | ssize_t res; | |
1242 | ||
1243 | ap.args.opcode = FUSE_READLINK; | |
1244 | ap.args.nodeid = get_node_id(inode); | |
1245 | ap.args.out_pages = true; | |
1246 | ap.args.out_argvar = true; | |
1247 | ap.args.page_zeroing = true; | |
1248 | ap.args.out_numargs = 1; | |
1249 | ap.args.out_args[0].size = desc.length; | |
1250 | res = fuse_simple_request(fc, &ap.args); | |
1251 | ||
1252 | fuse_invalidate_atime(inode); | |
1253 | ||
1254 | if (res < 0) | |
1255 | return res; | |
1256 | ||
1257 | if (WARN_ON(res >= PAGE_SIZE)) | |
1258 | return -EIO; | |
1259 | ||
1260 | link = page_address(page); | |
1261 | link[res] = '\0'; | |
1262 | ||
1263 | return 0; | |
1264 | } | |
1265 | ||
1266 | static const char *fuse_get_link(struct dentry *dentry, struct inode *inode, | |
1267 | struct delayed_call *callback) | |
1268 | { | |
1269 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1270 | struct page *page; | |
1271 | int err; | |
1272 | ||
1273 | err = -EIO; | |
1274 | if (fuse_is_bad(inode)) | |
1275 | goto out_err; | |
1276 | ||
1277 | if (fc->cache_symlinks) | |
1278 | return page_get_link(dentry, inode, callback); | |
1279 | ||
1280 | err = -ECHILD; | |
1281 | if (!dentry) | |
1282 | goto out_err; | |
1283 | ||
1284 | page = alloc_page(GFP_KERNEL); | |
1285 | err = -ENOMEM; | |
1286 | if (!page) | |
1287 | goto out_err; | |
1288 | ||
1289 | err = fuse_readlink_page(inode, page); | |
1290 | if (err) { | |
1291 | __free_page(page); | |
1292 | goto out_err; | |
1293 | } | |
1294 | ||
1295 | set_delayed_call(callback, page_put_link, page); | |
1296 | ||
1297 | return page_address(page); | |
1298 | ||
1299 | out_err: | |
1300 | return ERR_PTR(err); | |
1301 | } | |
1302 | ||
1303 | static int fuse_dir_open(struct inode *inode, struct file *file) | |
1304 | { | |
1305 | return fuse_open_common(inode, file, true); | |
1306 | } | |
1307 | ||
1308 | static int fuse_dir_release(struct inode *inode, struct file *file) | |
1309 | { | |
1310 | fuse_release_common(file, true); | |
1311 | ||
1312 | return 0; | |
1313 | } | |
1314 | ||
1315 | static int fuse_dir_fsync(struct file *file, loff_t start, loff_t end, | |
1316 | int datasync) | |
1317 | { | |
1318 | struct inode *inode = file->f_mapping->host; | |
1319 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1320 | int err; | |
1321 | ||
1322 | if (fuse_is_bad(inode)) | |
1323 | return -EIO; | |
1324 | ||
1325 | if (fc->no_fsyncdir) | |
1326 | return 0; | |
1327 | ||
1328 | inode_lock(inode); | |
1329 | err = fuse_fsync_common(file, start, end, datasync, FUSE_FSYNCDIR); | |
1330 | if (err == -ENOSYS) { | |
1331 | fc->no_fsyncdir = 1; | |
1332 | err = 0; | |
1333 | } | |
1334 | inode_unlock(inode); | |
1335 | ||
1336 | return err; | |
1337 | } | |
1338 | ||
1339 | static long fuse_dir_ioctl(struct file *file, unsigned int cmd, | |
1340 | unsigned long arg) | |
1341 | { | |
1342 | struct fuse_conn *fc = get_fuse_conn(file->f_mapping->host); | |
1343 | ||
1344 | /* FUSE_IOCTL_DIR only supported for API version >= 7.18 */ | |
1345 | if (fc->minor < 18) | |
1346 | return -ENOTTY; | |
1347 | ||
1348 | return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_DIR); | |
1349 | } | |
1350 | ||
1351 | static long fuse_dir_compat_ioctl(struct file *file, unsigned int cmd, | |
1352 | unsigned long arg) | |
1353 | { | |
1354 | struct fuse_conn *fc = get_fuse_conn(file->f_mapping->host); | |
1355 | ||
1356 | if (fc->minor < 18) | |
1357 | return -ENOTTY; | |
1358 | ||
1359 | return fuse_ioctl_common(file, cmd, arg, | |
1360 | FUSE_IOCTL_COMPAT | FUSE_IOCTL_DIR); | |
1361 | } | |
1362 | ||
1363 | static bool update_mtime(unsigned ivalid, bool trust_local_mtime) | |
1364 | { | |
1365 | /* Always update if mtime is explicitly set */ | |
1366 | if (ivalid & ATTR_MTIME_SET) | |
1367 | return true; | |
1368 | ||
1369 | /* Or if kernel i_mtime is the official one */ | |
1370 | if (trust_local_mtime) | |
1371 | return true; | |
1372 | ||
1373 | /* If it's an open(O_TRUNC) or an ftruncate(), don't update */ | |
1374 | if ((ivalid & ATTR_SIZE) && (ivalid & (ATTR_OPEN | ATTR_FILE))) | |
1375 | return false; | |
1376 | ||
1377 | /* In all other cases update */ | |
1378 | return true; | |
1379 | } | |
1380 | ||
1381 | static void iattr_to_fattr(struct fuse_conn *fc, struct iattr *iattr, | |
1382 | struct fuse_setattr_in *arg, bool trust_local_cmtime) | |
1383 | { | |
1384 | unsigned ivalid = iattr->ia_valid; | |
1385 | ||
1386 | if (ivalid & ATTR_MODE) | |
1387 | arg->valid |= FATTR_MODE, arg->mode = iattr->ia_mode; | |
1388 | if (ivalid & ATTR_UID) | |
1389 | arg->valid |= FATTR_UID, arg->uid = from_kuid(fc->user_ns, iattr->ia_uid); | |
1390 | if (ivalid & ATTR_GID) | |
1391 | arg->valid |= FATTR_GID, arg->gid = from_kgid(fc->user_ns, iattr->ia_gid); | |
1392 | if (ivalid & ATTR_SIZE) | |
1393 | arg->valid |= FATTR_SIZE, arg->size = iattr->ia_size; | |
1394 | if (ivalid & ATTR_ATIME) { | |
1395 | arg->valid |= FATTR_ATIME; | |
1396 | arg->atime = iattr->ia_atime.tv_sec; | |
1397 | arg->atimensec = iattr->ia_atime.tv_nsec; | |
1398 | if (!(ivalid & ATTR_ATIME_SET)) | |
1399 | arg->valid |= FATTR_ATIME_NOW; | |
1400 | } | |
1401 | if ((ivalid & ATTR_MTIME) && update_mtime(ivalid, trust_local_cmtime)) { | |
1402 | arg->valid |= FATTR_MTIME; | |
1403 | arg->mtime = iattr->ia_mtime.tv_sec; | |
1404 | arg->mtimensec = iattr->ia_mtime.tv_nsec; | |
1405 | if (!(ivalid & ATTR_MTIME_SET) && !trust_local_cmtime) | |
1406 | arg->valid |= FATTR_MTIME_NOW; | |
1407 | } | |
1408 | if ((ivalid & ATTR_CTIME) && trust_local_cmtime) { | |
1409 | arg->valid |= FATTR_CTIME; | |
1410 | arg->ctime = iattr->ia_ctime.tv_sec; | |
1411 | arg->ctimensec = iattr->ia_ctime.tv_nsec; | |
1412 | } | |
1413 | } | |
1414 | ||
1415 | /* | |
1416 | * Prevent concurrent writepages on inode | |
1417 | * | |
1418 | * This is done by adding a negative bias to the inode write counter | |
1419 | * and waiting for all pending writes to finish. | |
1420 | */ | |
1421 | void fuse_set_nowrite(struct inode *inode) | |
1422 | { | |
1423 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1424 | ||
1425 | BUG_ON(!inode_is_locked(inode)); | |
1426 | ||
1427 | spin_lock(&fi->lock); | |
1428 | BUG_ON(fi->writectr < 0); | |
1429 | fi->writectr += FUSE_NOWRITE; | |
1430 | spin_unlock(&fi->lock); | |
1431 | wait_event(fi->page_waitq, fi->writectr == FUSE_NOWRITE); | |
1432 | } | |
1433 | ||
1434 | /* | |
1435 | * Allow writepages on inode | |
1436 | * | |
1437 | * Remove the bias from the writecounter and send any queued | |
1438 | * writepages. | |
1439 | */ | |
1440 | static void __fuse_release_nowrite(struct inode *inode) | |
1441 | { | |
1442 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1443 | ||
1444 | BUG_ON(fi->writectr != FUSE_NOWRITE); | |
1445 | fi->writectr = 0; | |
1446 | fuse_flush_writepages(inode); | |
1447 | } | |
1448 | ||
1449 | void fuse_release_nowrite(struct inode *inode) | |
1450 | { | |
1451 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1452 | ||
1453 | spin_lock(&fi->lock); | |
1454 | __fuse_release_nowrite(inode); | |
1455 | spin_unlock(&fi->lock); | |
1456 | } | |
1457 | ||
1458 | static void fuse_setattr_fill(struct fuse_conn *fc, struct fuse_args *args, | |
1459 | struct inode *inode, | |
1460 | struct fuse_setattr_in *inarg_p, | |
1461 | struct fuse_attr_out *outarg_p) | |
1462 | { | |
1463 | args->opcode = FUSE_SETATTR; | |
1464 | args->nodeid = get_node_id(inode); | |
1465 | args->in_numargs = 1; | |
1466 | args->in_args[0].size = sizeof(*inarg_p); | |
1467 | args->in_args[0].value = inarg_p; | |
1468 | args->out_numargs = 1; | |
1469 | args->out_args[0].size = sizeof(*outarg_p); | |
1470 | args->out_args[0].value = outarg_p; | |
1471 | } | |
1472 | ||
1473 | /* | |
1474 | * Flush inode->i_mtime to the server | |
1475 | */ | |
1476 | int fuse_flush_times(struct inode *inode, struct fuse_file *ff) | |
1477 | { | |
1478 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1479 | FUSE_ARGS(args); | |
1480 | struct fuse_setattr_in inarg; | |
1481 | struct fuse_attr_out outarg; | |
1482 | ||
1483 | memset(&inarg, 0, sizeof(inarg)); | |
1484 | memset(&outarg, 0, sizeof(outarg)); | |
1485 | ||
1486 | inarg.valid = FATTR_MTIME; | |
1487 | inarg.mtime = inode->i_mtime.tv_sec; | |
1488 | inarg.mtimensec = inode->i_mtime.tv_nsec; | |
1489 | if (fc->minor >= 23) { | |
1490 | inarg.valid |= FATTR_CTIME; | |
1491 | inarg.ctime = inode->i_ctime.tv_sec; | |
1492 | inarg.ctimensec = inode->i_ctime.tv_nsec; | |
1493 | } | |
1494 | if (ff) { | |
1495 | inarg.valid |= FATTR_FH; | |
1496 | inarg.fh = ff->fh; | |
1497 | } | |
1498 | fuse_setattr_fill(fc, &args, inode, &inarg, &outarg); | |
1499 | ||
1500 | return fuse_simple_request(fc, &args); | |
1501 | } | |
1502 | ||
1503 | /* | |
1504 | * Set attributes, and at the same time refresh them. | |
1505 | * | |
1506 | * Truncation is slightly complicated, because the 'truncate' request | |
1507 | * may fail, in which case we don't want to touch the mapping. | |
1508 | * vmtruncate() doesn't allow for this case, so do the rlimit checking | |
1509 | * and the actual truncation by hand. | |
1510 | */ | |
1511 | int fuse_do_setattr(struct dentry *dentry, struct iattr *attr, | |
1512 | struct file *file) | |
1513 | { | |
1514 | struct inode *inode = d_inode(dentry); | |
1515 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1516 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1517 | FUSE_ARGS(args); | |
1518 | struct fuse_setattr_in inarg; | |
1519 | struct fuse_attr_out outarg; | |
1520 | bool is_truncate = false; | |
1521 | bool is_wb = fc->writeback_cache; | |
1522 | loff_t oldsize; | |
1523 | int err; | |
1524 | bool trust_local_cmtime = is_wb && S_ISREG(inode->i_mode); | |
1525 | ||
1526 | if (!fc->default_permissions) | |
1527 | attr->ia_valid |= ATTR_FORCE; | |
1528 | ||
1529 | err = setattr_prepare(dentry, attr); | |
1530 | if (err) | |
1531 | return err; | |
1532 | ||
1533 | if (attr->ia_valid & ATTR_OPEN) { | |
1534 | /* This is coming from open(..., ... | O_TRUNC); */ | |
1535 | WARN_ON(!(attr->ia_valid & ATTR_SIZE)); | |
1536 | WARN_ON(attr->ia_size != 0); | |
1537 | if (fc->atomic_o_trunc) { | |
1538 | /* | |
1539 | * No need to send request to userspace, since actual | |
1540 | * truncation has already been done by OPEN. But still | |
1541 | * need to truncate page cache. | |
1542 | */ | |
1543 | i_size_write(inode, 0); | |
1544 | truncate_pagecache(inode, 0); | |
1545 | return 0; | |
1546 | } | |
1547 | file = NULL; | |
1548 | } | |
1549 | ||
1550 | if (attr->ia_valid & ATTR_SIZE) { | |
1551 | if (WARN_ON(!S_ISREG(inode->i_mode))) | |
1552 | return -EIO; | |
1553 | is_truncate = true; | |
1554 | } | |
1555 | ||
1556 | /* Flush dirty data/metadata before non-truncate SETATTR */ | |
1557 | if (is_wb && S_ISREG(inode->i_mode) && | |
1558 | attr->ia_valid & | |
1559 | (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_MTIME_SET | | |
1560 | ATTR_TIMES_SET)) { | |
1561 | err = write_inode_now(inode, true); | |
1562 | if (err) | |
1563 | return err; | |
1564 | ||
1565 | fuse_set_nowrite(inode); | |
1566 | fuse_release_nowrite(inode); | |
1567 | } | |
1568 | ||
1569 | if (is_truncate) { | |
1570 | fuse_set_nowrite(inode); | |
1571 | set_bit(FUSE_I_SIZE_UNSTABLE, &fi->state); | |
1572 | if (trust_local_cmtime && attr->ia_size != inode->i_size) | |
1573 | attr->ia_valid |= ATTR_MTIME | ATTR_CTIME; | |
1574 | } | |
1575 | ||
1576 | memset(&inarg, 0, sizeof(inarg)); | |
1577 | memset(&outarg, 0, sizeof(outarg)); | |
1578 | iattr_to_fattr(fc, attr, &inarg, trust_local_cmtime); | |
1579 | if (file) { | |
1580 | struct fuse_file *ff = file->private_data; | |
1581 | inarg.valid |= FATTR_FH; | |
1582 | inarg.fh = ff->fh; | |
1583 | } | |
1584 | if (attr->ia_valid & ATTR_SIZE) { | |
1585 | /* For mandatory locking in truncate */ | |
1586 | inarg.valid |= FATTR_LOCKOWNER; | |
1587 | inarg.lock_owner = fuse_lock_owner_id(fc, current->files); | |
1588 | } | |
1589 | fuse_setattr_fill(fc, &args, inode, &inarg, &outarg); | |
1590 | err = fuse_simple_request(fc, &args); | |
1591 | if (err) { | |
1592 | if (err == -EINTR) | |
1593 | fuse_invalidate_attr(inode); | |
1594 | goto error; | |
1595 | } | |
1596 | ||
1597 | if (fuse_invalid_attr(&outarg.attr) || | |
1598 | (inode->i_mode ^ outarg.attr.mode) & S_IFMT) { | |
1599 | fuse_make_bad(inode); | |
1600 | err = -EIO; | |
1601 | goto error; | |
1602 | } | |
1603 | ||
1604 | spin_lock(&fi->lock); | |
1605 | /* the kernel maintains i_mtime locally */ | |
1606 | if (trust_local_cmtime) { | |
1607 | if (attr->ia_valid & ATTR_MTIME) | |
1608 | inode->i_mtime = attr->ia_mtime; | |
1609 | if (attr->ia_valid & ATTR_CTIME) | |
1610 | inode->i_ctime = attr->ia_ctime; | |
1611 | /* FIXME: clear I_DIRTY_SYNC? */ | |
1612 | } | |
1613 | ||
1614 | fuse_change_attributes_common(inode, &outarg.attr, | |
1615 | attr_timeout(&outarg)); | |
1616 | oldsize = inode->i_size; | |
1617 | /* see the comment in fuse_change_attributes() */ | |
1618 | if (!is_wb || is_truncate || !S_ISREG(inode->i_mode)) | |
1619 | i_size_write(inode, outarg.attr.size); | |
1620 | ||
1621 | if (is_truncate) { | |
1622 | /* NOTE: this may release/reacquire fi->lock */ | |
1623 | __fuse_release_nowrite(inode); | |
1624 | } | |
1625 | spin_unlock(&fi->lock); | |
1626 | ||
1627 | /* | |
1628 | * Only call invalidate_inode_pages2() after removing | |
1629 | * FUSE_NOWRITE, otherwise fuse_launder_page() would deadlock. | |
1630 | */ | |
1631 | if ((is_truncate || !is_wb) && | |
1632 | S_ISREG(inode->i_mode) && oldsize != outarg.attr.size) { | |
1633 | truncate_pagecache(inode, outarg.attr.size); | |
1634 | invalidate_inode_pages2(inode->i_mapping); | |
1635 | } | |
1636 | ||
1637 | clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state); | |
1638 | return 0; | |
1639 | ||
1640 | error: | |
1641 | if (is_truncate) | |
1642 | fuse_release_nowrite(inode); | |
1643 | ||
1644 | clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state); | |
1645 | return err; | |
1646 | } | |
1647 | ||
1648 | static int fuse_setattr(struct dentry *entry, struct iattr *attr) | |
1649 | { | |
1650 | struct inode *inode = d_inode(entry); | |
1651 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1652 | struct file *file = (attr->ia_valid & ATTR_FILE) ? attr->ia_file : NULL; | |
1653 | int ret; | |
1654 | ||
1655 | if (fuse_is_bad(inode)) | |
1656 | return -EIO; | |
1657 | ||
1658 | if (!fuse_allow_current_process(get_fuse_conn(inode))) | |
1659 | return -EACCES; | |
1660 | ||
1661 | if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) { | |
1662 | attr->ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | | |
1663 | ATTR_MODE); | |
1664 | ||
1665 | /* | |
1666 | * The only sane way to reliably kill suid/sgid is to do it in | |
1667 | * the userspace filesystem | |
1668 | * | |
1669 | * This should be done on write(), truncate() and chown(). | |
1670 | */ | |
1671 | if (!fc->handle_killpriv) { | |
1672 | /* | |
1673 | * ia_mode calculation may have used stale i_mode. | |
1674 | * Refresh and recalculate. | |
1675 | */ | |
1676 | ret = fuse_do_getattr(inode, NULL, file); | |
1677 | if (ret) | |
1678 | return ret; | |
1679 | ||
1680 | attr->ia_mode = inode->i_mode; | |
1681 | if (inode->i_mode & S_ISUID) { | |
1682 | attr->ia_valid |= ATTR_MODE; | |
1683 | attr->ia_mode &= ~S_ISUID; | |
1684 | } | |
1685 | if ((inode->i_mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) { | |
1686 | attr->ia_valid |= ATTR_MODE; | |
1687 | attr->ia_mode &= ~S_ISGID; | |
1688 | } | |
1689 | } | |
1690 | } | |
1691 | if (!attr->ia_valid) | |
1692 | return 0; | |
1693 | ||
1694 | ret = fuse_do_setattr(entry, attr, file); | |
1695 | if (!ret) { | |
1696 | /* | |
1697 | * If filesystem supports acls it may have updated acl xattrs in | |
1698 | * the filesystem, so forget cached acls for the inode. | |
1699 | */ | |
1700 | if (fc->posix_acl) | |
1701 | forget_all_cached_acls(inode); | |
1702 | ||
1703 | /* Directory mode changed, may need to revalidate access */ | |
1704 | if (d_is_dir(entry) && (attr->ia_valid & ATTR_MODE)) | |
1705 | fuse_invalidate_entry_cache(entry); | |
1706 | } | |
1707 | return ret; | |
1708 | } | |
1709 | ||
1710 | static int fuse_getattr(const struct path *path, struct kstat *stat, | |
1711 | u32 request_mask, unsigned int flags) | |
1712 | { | |
1713 | struct inode *inode = d_inode(path->dentry); | |
1714 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1715 | ||
1716 | if (fuse_is_bad(inode)) | |
1717 | return -EIO; | |
1718 | ||
1719 | if (!fuse_allow_current_process(fc)) | |
1720 | return -EACCES; | |
1721 | ||
1722 | return fuse_update_get_attr(inode, NULL, stat, request_mask, flags); | |
1723 | } | |
1724 | ||
1725 | static const struct inode_operations fuse_dir_inode_operations = { | |
1726 | .lookup = fuse_lookup, | |
1727 | .mkdir = fuse_mkdir, | |
1728 | .symlink = fuse_symlink, | |
1729 | .unlink = fuse_unlink, | |
1730 | .rmdir = fuse_rmdir, | |
1731 | .rename = fuse_rename2, | |
1732 | .link = fuse_link, | |
1733 | .setattr = fuse_setattr, | |
1734 | .create = fuse_create, | |
1735 | .atomic_open = fuse_atomic_open, | |
1736 | .mknod = fuse_mknod, | |
1737 | .permission = fuse_permission, | |
1738 | .getattr = fuse_getattr, | |
1739 | .listxattr = fuse_listxattr, | |
1740 | .get_acl = fuse_get_acl, | |
1741 | .set_acl = fuse_set_acl, | |
1742 | }; | |
1743 | ||
1744 | static const struct file_operations fuse_dir_operations = { | |
1745 | .llseek = generic_file_llseek, | |
1746 | .read = generic_read_dir, | |
1747 | .iterate_shared = fuse_readdir, | |
1748 | .open = fuse_dir_open, | |
1749 | .release = fuse_dir_release, | |
1750 | .fsync = fuse_dir_fsync, | |
1751 | .unlocked_ioctl = fuse_dir_ioctl, | |
1752 | .compat_ioctl = fuse_dir_compat_ioctl, | |
1753 | }; | |
1754 | ||
1755 | static const struct inode_operations fuse_common_inode_operations = { | |
1756 | .setattr = fuse_setattr, | |
1757 | .permission = fuse_permission, | |
1758 | .getattr = fuse_getattr, | |
1759 | .listxattr = fuse_listxattr, | |
1760 | .get_acl = fuse_get_acl, | |
1761 | .set_acl = fuse_set_acl, | |
1762 | }; | |
1763 | ||
1764 | static const struct inode_operations fuse_symlink_inode_operations = { | |
1765 | .setattr = fuse_setattr, | |
1766 | .get_link = fuse_get_link, | |
1767 | .getattr = fuse_getattr, | |
1768 | .listxattr = fuse_listxattr, | |
1769 | }; | |
1770 | ||
1771 | void fuse_init_common(struct inode *inode) | |
1772 | { | |
1773 | inode->i_op = &fuse_common_inode_operations; | |
1774 | } | |
1775 | ||
1776 | void fuse_init_dir(struct inode *inode) | |
1777 | { | |
1778 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1779 | ||
1780 | inode->i_op = &fuse_dir_inode_operations; | |
1781 | inode->i_fop = &fuse_dir_operations; | |
1782 | ||
1783 | spin_lock_init(&fi->rdc.lock); | |
1784 | fi->rdc.cached = false; | |
1785 | fi->rdc.size = 0; | |
1786 | fi->rdc.pos = 0; | |
1787 | fi->rdc.version = 0; | |
1788 | } | |
1789 | ||
1790 | static int fuse_symlink_readpage(struct file *null, struct page *page) | |
1791 | { | |
1792 | int err = fuse_readlink_page(page->mapping->host, page); | |
1793 | ||
1794 | if (!err) | |
1795 | SetPageUptodate(page); | |
1796 | ||
1797 | unlock_page(page); | |
1798 | ||
1799 | return err; | |
1800 | } | |
1801 | ||
1802 | static const struct address_space_operations fuse_symlink_aops = { | |
1803 | .readpage = fuse_symlink_readpage, | |
1804 | }; | |
1805 | ||
1806 | void fuse_init_symlink(struct inode *inode) | |
1807 | { | |
1808 | inode->i_op = &fuse_symlink_inode_operations; | |
1809 | inode->i_data.a_ops = &fuse_symlink_aops; | |
1810 | inode_nohighmem(inode); | |
1811 | } |