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new helper: file_inode(file)
[GitHub/LineageOS/android_kernel_samsung_universal7580.git] / fs / fuse / dir.c
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
17 #if BITS_PER_LONG >= 64
18 static inline void fuse_dentry_settime(struct dentry *entry, u64 time)
19 {
20 entry->d_time = time;
21 }
22
23 static inline u64 fuse_dentry_time(struct dentry *entry)
24 {
25 return entry->d_time;
26 }
27 #else
28 /*
29 * On 32 bit archs store the high 32 bits of time in d_fsdata
30 */
31 static void fuse_dentry_settime(struct dentry *entry, u64 time)
32 {
33 entry->d_time = time;
34 entry->d_fsdata = (void *) (unsigned long) (time >> 32);
35 }
36
37 static u64 fuse_dentry_time(struct dentry *entry)
38 {
39 return (u64) entry->d_time +
40 ((u64) (unsigned long) entry->d_fsdata << 32);
41 }
42 #endif
43
44 /*
45 * FUSE caches dentries and attributes with separate timeout. The
46 * time in jiffies until the dentry/attributes are valid is stored in
47 * dentry->d_time and fuse_inode->i_time respectively.
48 */
49
50 /*
51 * Calculate the time in jiffies until a dentry/attributes are valid
52 */
53 static u64 time_to_jiffies(unsigned long sec, unsigned long nsec)
54 {
55 if (sec || nsec) {
56 struct timespec ts = {sec, nsec};
57 return get_jiffies_64() + timespec_to_jiffies(&ts);
58 } else
59 return 0;
60 }
61
62 /*
63 * Set dentry and possibly attribute timeouts from the lookup/mk*
64 * replies
65 */
66 static void fuse_change_entry_timeout(struct dentry *entry,
67 struct fuse_entry_out *o)
68 {
69 fuse_dentry_settime(entry,
70 time_to_jiffies(o->entry_valid, o->entry_valid_nsec));
71 }
72
73 static u64 attr_timeout(struct fuse_attr_out *o)
74 {
75 return time_to_jiffies(o->attr_valid, o->attr_valid_nsec);
76 }
77
78 static u64 entry_attr_timeout(struct fuse_entry_out *o)
79 {
80 return time_to_jiffies(o->attr_valid, o->attr_valid_nsec);
81 }
82
83 /*
84 * Mark the attributes as stale, so that at the next call to
85 * ->getattr() they will be fetched from userspace
86 */
87 void fuse_invalidate_attr(struct inode *inode)
88 {
89 get_fuse_inode(inode)->i_time = 0;
90 }
91
92 /*
93 * Just mark the entry as stale, so that a next attempt to look it up
94 * will result in a new lookup call to userspace
95 *
96 * This is called when a dentry is about to become negative and the
97 * timeout is unknown (unlink, rmdir, rename and in some cases
98 * lookup)
99 */
100 void fuse_invalidate_entry_cache(struct dentry *entry)
101 {
102 fuse_dentry_settime(entry, 0);
103 }
104
105 /*
106 * Same as fuse_invalidate_entry_cache(), but also try to remove the
107 * dentry from the hash
108 */
109 static void fuse_invalidate_entry(struct dentry *entry)
110 {
111 d_invalidate(entry);
112 fuse_invalidate_entry_cache(entry);
113 }
114
115 static void fuse_lookup_init(struct fuse_conn *fc, struct fuse_req *req,
116 u64 nodeid, struct qstr *name,
117 struct fuse_entry_out *outarg)
118 {
119 memset(outarg, 0, sizeof(struct fuse_entry_out));
120 req->in.h.opcode = FUSE_LOOKUP;
121 req->in.h.nodeid = nodeid;
122 req->in.numargs = 1;
123 req->in.args[0].size = name->len + 1;
124 req->in.args[0].value = name->name;
125 req->out.numargs = 1;
126 if (fc->minor < 9)
127 req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
128 else
129 req->out.args[0].size = sizeof(struct fuse_entry_out);
130 req->out.args[0].value = outarg;
131 }
132
133 u64 fuse_get_attr_version(struct fuse_conn *fc)
134 {
135 u64 curr_version;
136
137 /*
138 * The spin lock isn't actually needed on 64bit archs, but we
139 * don't yet care too much about such optimizations.
140 */
141 spin_lock(&fc->lock);
142 curr_version = fc->attr_version;
143 spin_unlock(&fc->lock);
144
145 return curr_version;
146 }
147
148 /*
149 * Check whether the dentry is still valid
150 *
151 * If the entry validity timeout has expired and the dentry is
152 * positive, try to redo the lookup. If the lookup results in a
153 * different inode, then let the VFS invalidate the dentry and redo
154 * the lookup once more. If the lookup results in the same inode,
155 * then refresh the attributes, timeouts and mark the dentry valid.
156 */
157 static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
158 {
159 struct inode *inode;
160
161 inode = ACCESS_ONCE(entry->d_inode);
162 if (inode && is_bad_inode(inode))
163 return 0;
164 else if (fuse_dentry_time(entry) < get_jiffies_64()) {
165 int err;
166 struct fuse_entry_out outarg;
167 struct fuse_conn *fc;
168 struct fuse_req *req;
169 struct fuse_forget_link *forget;
170 struct dentry *parent;
171 u64 attr_version;
172
173 /* For negative dentries, always do a fresh lookup */
174 if (!inode)
175 return 0;
176
177 if (flags & LOOKUP_RCU)
178 return -ECHILD;
179
180 fc = get_fuse_conn(inode);
181 req = fuse_get_req(fc);
182 if (IS_ERR(req))
183 return 0;
184
185 forget = fuse_alloc_forget();
186 if (!forget) {
187 fuse_put_request(fc, req);
188 return 0;
189 }
190
191 attr_version = fuse_get_attr_version(fc);
192
193 parent = dget_parent(entry);
194 fuse_lookup_init(fc, req, get_node_id(parent->d_inode),
195 &entry->d_name, &outarg);
196 fuse_request_send(fc, req);
197 dput(parent);
198 err = req->out.h.error;
199 fuse_put_request(fc, req);
200 /* Zero nodeid is same as -ENOENT */
201 if (!err && !outarg.nodeid)
202 err = -ENOENT;
203 if (!err) {
204 struct fuse_inode *fi = get_fuse_inode(inode);
205 if (outarg.nodeid != get_node_id(inode)) {
206 fuse_queue_forget(fc, forget, outarg.nodeid, 1);
207 return 0;
208 }
209 spin_lock(&fc->lock);
210 fi->nlookup++;
211 spin_unlock(&fc->lock);
212 }
213 kfree(forget);
214 if (err || (outarg.attr.mode ^ inode->i_mode) & S_IFMT)
215 return 0;
216
217 fuse_change_attributes(inode, &outarg.attr,
218 entry_attr_timeout(&outarg),
219 attr_version);
220 fuse_change_entry_timeout(entry, &outarg);
221 }
222 return 1;
223 }
224
225 static int invalid_nodeid(u64 nodeid)
226 {
227 return !nodeid || nodeid == FUSE_ROOT_ID;
228 }
229
230 const struct dentry_operations fuse_dentry_operations = {
231 .d_revalidate = fuse_dentry_revalidate,
232 };
233
234 int fuse_valid_type(int m)
235 {
236 return S_ISREG(m) || S_ISDIR(m) || S_ISLNK(m) || S_ISCHR(m) ||
237 S_ISBLK(m) || S_ISFIFO(m) || S_ISSOCK(m);
238 }
239
240 /*
241 * Add a directory inode to a dentry, ensuring that no other dentry
242 * refers to this inode. Called with fc->inst_mutex.
243 */
244 static struct dentry *fuse_d_add_directory(struct dentry *entry,
245 struct inode *inode)
246 {
247 struct dentry *alias = d_find_alias(inode);
248 if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) {
249 /* This tries to shrink the subtree below alias */
250 fuse_invalidate_entry(alias);
251 dput(alias);
252 if (!hlist_empty(&inode->i_dentry))
253 return ERR_PTR(-EBUSY);
254 } else {
255 dput(alias);
256 }
257 return d_splice_alias(inode, entry);
258 }
259
260 int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
261 struct fuse_entry_out *outarg, struct inode **inode)
262 {
263 struct fuse_conn *fc = get_fuse_conn_super(sb);
264 struct fuse_req *req;
265 struct fuse_forget_link *forget;
266 u64 attr_version;
267 int err;
268
269 *inode = NULL;
270 err = -ENAMETOOLONG;
271 if (name->len > FUSE_NAME_MAX)
272 goto out;
273
274 req = fuse_get_req(fc);
275 err = PTR_ERR(req);
276 if (IS_ERR(req))
277 goto out;
278
279 forget = fuse_alloc_forget();
280 err = -ENOMEM;
281 if (!forget) {
282 fuse_put_request(fc, req);
283 goto out;
284 }
285
286 attr_version = fuse_get_attr_version(fc);
287
288 fuse_lookup_init(fc, req, nodeid, name, outarg);
289 fuse_request_send(fc, req);
290 err = req->out.h.error;
291 fuse_put_request(fc, req);
292 /* Zero nodeid is same as -ENOENT, but with valid timeout */
293 if (err || !outarg->nodeid)
294 goto out_put_forget;
295
296 err = -EIO;
297 if (!outarg->nodeid)
298 goto out_put_forget;
299 if (!fuse_valid_type(outarg->attr.mode))
300 goto out_put_forget;
301
302 *inode = fuse_iget(sb, outarg->nodeid, outarg->generation,
303 &outarg->attr, entry_attr_timeout(outarg),
304 attr_version);
305 err = -ENOMEM;
306 if (!*inode) {
307 fuse_queue_forget(fc, forget, outarg->nodeid, 1);
308 goto out;
309 }
310 err = 0;
311
312 out_put_forget:
313 kfree(forget);
314 out:
315 return err;
316 }
317
318 static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
319 unsigned int flags)
320 {
321 int err;
322 struct fuse_entry_out outarg;
323 struct inode *inode;
324 struct dentry *newent;
325 struct fuse_conn *fc = get_fuse_conn(dir);
326 bool outarg_valid = true;
327
328 err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
329 &outarg, &inode);
330 if (err == -ENOENT) {
331 outarg_valid = false;
332 err = 0;
333 }
334 if (err)
335 goto out_err;
336
337 err = -EIO;
338 if (inode && get_node_id(inode) == FUSE_ROOT_ID)
339 goto out_iput;
340
341 if (inode && S_ISDIR(inode->i_mode)) {
342 mutex_lock(&fc->inst_mutex);
343 newent = fuse_d_add_directory(entry, inode);
344 mutex_unlock(&fc->inst_mutex);
345 err = PTR_ERR(newent);
346 if (IS_ERR(newent))
347 goto out_iput;
348 } else {
349 newent = d_splice_alias(inode, entry);
350 }
351
352 entry = newent ? newent : entry;
353 if (outarg_valid)
354 fuse_change_entry_timeout(entry, &outarg);
355 else
356 fuse_invalidate_entry_cache(entry);
357
358 return newent;
359
360 out_iput:
361 iput(inode);
362 out_err:
363 return ERR_PTR(err);
364 }
365
366 /*
367 * Atomic create+open operation
368 *
369 * If the filesystem doesn't support this, then fall back to separate
370 * 'mknod' + 'open' requests.
371 */
372 static int fuse_create_open(struct inode *dir, struct dentry *entry,
373 struct file *file, unsigned flags,
374 umode_t mode, int *opened)
375 {
376 int err;
377 struct inode *inode;
378 struct fuse_conn *fc = get_fuse_conn(dir);
379 struct fuse_req *req;
380 struct fuse_forget_link *forget;
381 struct fuse_create_in inarg;
382 struct fuse_open_out outopen;
383 struct fuse_entry_out outentry;
384 struct fuse_file *ff;
385
386 /* Userspace expects S_IFREG in create mode */
387 BUG_ON((mode & S_IFMT) != S_IFREG);
388
389 forget = fuse_alloc_forget();
390 err = -ENOMEM;
391 if (!forget)
392 goto out_err;
393
394 req = fuse_get_req(fc);
395 err = PTR_ERR(req);
396 if (IS_ERR(req))
397 goto out_put_forget_req;
398
399 err = -ENOMEM;
400 ff = fuse_file_alloc(fc);
401 if (!ff)
402 goto out_put_request;
403
404 if (!fc->dont_mask)
405 mode &= ~current_umask();
406
407 flags &= ~O_NOCTTY;
408 memset(&inarg, 0, sizeof(inarg));
409 memset(&outentry, 0, sizeof(outentry));
410 inarg.flags = flags;
411 inarg.mode = mode;
412 inarg.umask = current_umask();
413 req->in.h.opcode = FUSE_CREATE;
414 req->in.h.nodeid = get_node_id(dir);
415 req->in.numargs = 2;
416 req->in.args[0].size = fc->minor < 12 ? sizeof(struct fuse_open_in) :
417 sizeof(inarg);
418 req->in.args[0].value = &inarg;
419 req->in.args[1].size = entry->d_name.len + 1;
420 req->in.args[1].value = entry->d_name.name;
421 req->out.numargs = 2;
422 if (fc->minor < 9)
423 req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
424 else
425 req->out.args[0].size = sizeof(outentry);
426 req->out.args[0].value = &outentry;
427 req->out.args[1].size = sizeof(outopen);
428 req->out.args[1].value = &outopen;
429 fuse_request_send(fc, req);
430 err = req->out.h.error;
431 if (err)
432 goto out_free_ff;
433
434 err = -EIO;
435 if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid))
436 goto out_free_ff;
437
438 fuse_put_request(fc, req);
439 ff->fh = outopen.fh;
440 ff->nodeid = outentry.nodeid;
441 ff->open_flags = outopen.open_flags;
442 inode = fuse_iget(dir->i_sb, outentry.nodeid, outentry.generation,
443 &outentry.attr, entry_attr_timeout(&outentry), 0);
444 if (!inode) {
445 flags &= ~(O_CREAT | O_EXCL | O_TRUNC);
446 fuse_sync_release(ff, flags);
447 fuse_queue_forget(fc, forget, outentry.nodeid, 1);
448 err = -ENOMEM;
449 goto out_err;
450 }
451 kfree(forget);
452 d_instantiate(entry, inode);
453 fuse_change_entry_timeout(entry, &outentry);
454 fuse_invalidate_attr(dir);
455 err = finish_open(file, entry, generic_file_open, opened);
456 if (err) {
457 fuse_sync_release(ff, flags);
458 } else {
459 file->private_data = fuse_file_get(ff);
460 fuse_finish_open(inode, file);
461 }
462 return err;
463
464 out_free_ff:
465 fuse_file_free(ff);
466 out_put_request:
467 fuse_put_request(fc, req);
468 out_put_forget_req:
469 kfree(forget);
470 out_err:
471 return err;
472 }
473
474 static int fuse_mknod(struct inode *, struct dentry *, umode_t, dev_t);
475 static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
476 struct file *file, unsigned flags,
477 umode_t mode, int *opened)
478 {
479 int err;
480 struct fuse_conn *fc = get_fuse_conn(dir);
481 struct dentry *res = NULL;
482
483 if (d_unhashed(entry)) {
484 res = fuse_lookup(dir, entry, 0);
485 if (IS_ERR(res))
486 return PTR_ERR(res);
487
488 if (res)
489 entry = res;
490 }
491
492 if (!(flags & O_CREAT) || entry->d_inode)
493 goto no_open;
494
495 /* Only creates */
496 *opened |= FILE_CREATED;
497
498 if (fc->no_create)
499 goto mknod;
500
501 err = fuse_create_open(dir, entry, file, flags, mode, opened);
502 if (err == -ENOSYS) {
503 fc->no_create = 1;
504 goto mknod;
505 }
506 out_dput:
507 dput(res);
508 return err;
509
510 mknod:
511 err = fuse_mknod(dir, entry, mode, 0);
512 if (err)
513 goto out_dput;
514 no_open:
515 return finish_no_open(file, res);
516 }
517
518 /*
519 * Code shared between mknod, mkdir, symlink and link
520 */
521 static int create_new_entry(struct fuse_conn *fc, struct fuse_req *req,
522 struct inode *dir, struct dentry *entry,
523 umode_t mode)
524 {
525 struct fuse_entry_out outarg;
526 struct inode *inode;
527 int err;
528 struct fuse_forget_link *forget;
529
530 forget = fuse_alloc_forget();
531 if (!forget) {
532 fuse_put_request(fc, req);
533 return -ENOMEM;
534 }
535
536 memset(&outarg, 0, sizeof(outarg));
537 req->in.h.nodeid = get_node_id(dir);
538 req->out.numargs = 1;
539 if (fc->minor < 9)
540 req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
541 else
542 req->out.args[0].size = sizeof(outarg);
543 req->out.args[0].value = &outarg;
544 fuse_request_send(fc, req);
545 err = req->out.h.error;
546 fuse_put_request(fc, req);
547 if (err)
548 goto out_put_forget_req;
549
550 err = -EIO;
551 if (invalid_nodeid(outarg.nodeid))
552 goto out_put_forget_req;
553
554 if ((outarg.attr.mode ^ mode) & S_IFMT)
555 goto out_put_forget_req;
556
557 inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation,
558 &outarg.attr, entry_attr_timeout(&outarg), 0);
559 if (!inode) {
560 fuse_queue_forget(fc, forget, outarg.nodeid, 1);
561 return -ENOMEM;
562 }
563 kfree(forget);
564
565 if (S_ISDIR(inode->i_mode)) {
566 struct dentry *alias;
567 mutex_lock(&fc->inst_mutex);
568 alias = d_find_alias(inode);
569 if (alias) {
570 /* New directory must have moved since mkdir */
571 mutex_unlock(&fc->inst_mutex);
572 dput(alias);
573 iput(inode);
574 return -EBUSY;
575 }
576 d_instantiate(entry, inode);
577 mutex_unlock(&fc->inst_mutex);
578 } else
579 d_instantiate(entry, inode);
580
581 fuse_change_entry_timeout(entry, &outarg);
582 fuse_invalidate_attr(dir);
583 return 0;
584
585 out_put_forget_req:
586 kfree(forget);
587 return err;
588 }
589
590 static int fuse_mknod(struct inode *dir, struct dentry *entry, umode_t mode,
591 dev_t rdev)
592 {
593 struct fuse_mknod_in inarg;
594 struct fuse_conn *fc = get_fuse_conn(dir);
595 struct fuse_req *req = fuse_get_req(fc);
596 if (IS_ERR(req))
597 return PTR_ERR(req);
598
599 if (!fc->dont_mask)
600 mode &= ~current_umask();
601
602 memset(&inarg, 0, sizeof(inarg));
603 inarg.mode = mode;
604 inarg.rdev = new_encode_dev(rdev);
605 inarg.umask = current_umask();
606 req->in.h.opcode = FUSE_MKNOD;
607 req->in.numargs = 2;
608 req->in.args[0].size = fc->minor < 12 ? FUSE_COMPAT_MKNOD_IN_SIZE :
609 sizeof(inarg);
610 req->in.args[0].value = &inarg;
611 req->in.args[1].size = entry->d_name.len + 1;
612 req->in.args[1].value = entry->d_name.name;
613 return create_new_entry(fc, req, dir, entry, mode);
614 }
615
616 static int fuse_create(struct inode *dir, struct dentry *entry, umode_t mode,
617 bool excl)
618 {
619 return fuse_mknod(dir, entry, mode, 0);
620 }
621
622 static int fuse_mkdir(struct inode *dir, struct dentry *entry, umode_t mode)
623 {
624 struct fuse_mkdir_in inarg;
625 struct fuse_conn *fc = get_fuse_conn(dir);
626 struct fuse_req *req = fuse_get_req(fc);
627 if (IS_ERR(req))
628 return PTR_ERR(req);
629
630 if (!fc->dont_mask)
631 mode &= ~current_umask();
632
633 memset(&inarg, 0, sizeof(inarg));
634 inarg.mode = mode;
635 inarg.umask = current_umask();
636 req->in.h.opcode = FUSE_MKDIR;
637 req->in.numargs = 2;
638 req->in.args[0].size = sizeof(inarg);
639 req->in.args[0].value = &inarg;
640 req->in.args[1].size = entry->d_name.len + 1;
641 req->in.args[1].value = entry->d_name.name;
642 return create_new_entry(fc, req, dir, entry, S_IFDIR);
643 }
644
645 static int fuse_symlink(struct inode *dir, struct dentry *entry,
646 const char *link)
647 {
648 struct fuse_conn *fc = get_fuse_conn(dir);
649 unsigned len = strlen(link) + 1;
650 struct fuse_req *req = fuse_get_req(fc);
651 if (IS_ERR(req))
652 return PTR_ERR(req);
653
654 req->in.h.opcode = FUSE_SYMLINK;
655 req->in.numargs = 2;
656 req->in.args[0].size = entry->d_name.len + 1;
657 req->in.args[0].value = entry->d_name.name;
658 req->in.args[1].size = len;
659 req->in.args[1].value = link;
660 return create_new_entry(fc, req, dir, entry, S_IFLNK);
661 }
662
663 static int fuse_unlink(struct inode *dir, struct dentry *entry)
664 {
665 int err;
666 struct fuse_conn *fc = get_fuse_conn(dir);
667 struct fuse_req *req = fuse_get_req(fc);
668 if (IS_ERR(req))
669 return PTR_ERR(req);
670
671 req->in.h.opcode = FUSE_UNLINK;
672 req->in.h.nodeid = get_node_id(dir);
673 req->in.numargs = 1;
674 req->in.args[0].size = entry->d_name.len + 1;
675 req->in.args[0].value = entry->d_name.name;
676 fuse_request_send(fc, req);
677 err = req->out.h.error;
678 fuse_put_request(fc, req);
679 if (!err) {
680 struct inode *inode = entry->d_inode;
681 struct fuse_inode *fi = get_fuse_inode(inode);
682
683 spin_lock(&fc->lock);
684 fi->attr_version = ++fc->attr_version;
685 drop_nlink(inode);
686 spin_unlock(&fc->lock);
687 fuse_invalidate_attr(inode);
688 fuse_invalidate_attr(dir);
689 fuse_invalidate_entry_cache(entry);
690 } else if (err == -EINTR)
691 fuse_invalidate_entry(entry);
692 return err;
693 }
694
695 static int fuse_rmdir(struct inode *dir, struct dentry *entry)
696 {
697 int err;
698 struct fuse_conn *fc = get_fuse_conn(dir);
699 struct fuse_req *req = fuse_get_req(fc);
700 if (IS_ERR(req))
701 return PTR_ERR(req);
702
703 req->in.h.opcode = FUSE_RMDIR;
704 req->in.h.nodeid = get_node_id(dir);
705 req->in.numargs = 1;
706 req->in.args[0].size = entry->d_name.len + 1;
707 req->in.args[0].value = entry->d_name.name;
708 fuse_request_send(fc, req);
709 err = req->out.h.error;
710 fuse_put_request(fc, req);
711 if (!err) {
712 clear_nlink(entry->d_inode);
713 fuse_invalidate_attr(dir);
714 fuse_invalidate_entry_cache(entry);
715 } else if (err == -EINTR)
716 fuse_invalidate_entry(entry);
717 return err;
718 }
719
720 static int fuse_rename(struct inode *olddir, struct dentry *oldent,
721 struct inode *newdir, struct dentry *newent)
722 {
723 int err;
724 struct fuse_rename_in inarg;
725 struct fuse_conn *fc = get_fuse_conn(olddir);
726 struct fuse_req *req = fuse_get_req(fc);
727
728 if (IS_ERR(req))
729 return PTR_ERR(req);
730
731 memset(&inarg, 0, sizeof(inarg));
732 inarg.newdir = get_node_id(newdir);
733 req->in.h.opcode = FUSE_RENAME;
734 req->in.h.nodeid = get_node_id(olddir);
735 req->in.numargs = 3;
736 req->in.args[0].size = sizeof(inarg);
737 req->in.args[0].value = &inarg;
738 req->in.args[1].size = oldent->d_name.len + 1;
739 req->in.args[1].value = oldent->d_name.name;
740 req->in.args[2].size = newent->d_name.len + 1;
741 req->in.args[2].value = newent->d_name.name;
742 fuse_request_send(fc, req);
743 err = req->out.h.error;
744 fuse_put_request(fc, req);
745 if (!err) {
746 /* ctime changes */
747 fuse_invalidate_attr(oldent->d_inode);
748
749 fuse_invalidate_attr(olddir);
750 if (olddir != newdir)
751 fuse_invalidate_attr(newdir);
752
753 /* newent will end up negative */
754 if (newent->d_inode) {
755 fuse_invalidate_attr(newent->d_inode);
756 fuse_invalidate_entry_cache(newent);
757 }
758 } else if (err == -EINTR) {
759 /* If request was interrupted, DEITY only knows if the
760 rename actually took place. If the invalidation
761 fails (e.g. some process has CWD under the renamed
762 directory), then there can be inconsistency between
763 the dcache and the real filesystem. Tough luck. */
764 fuse_invalidate_entry(oldent);
765 if (newent->d_inode)
766 fuse_invalidate_entry(newent);
767 }
768
769 return err;
770 }
771
772 static int fuse_link(struct dentry *entry, struct inode *newdir,
773 struct dentry *newent)
774 {
775 int err;
776 struct fuse_link_in inarg;
777 struct inode *inode = entry->d_inode;
778 struct fuse_conn *fc = get_fuse_conn(inode);
779 struct fuse_req *req = fuse_get_req(fc);
780 if (IS_ERR(req))
781 return PTR_ERR(req);
782
783 memset(&inarg, 0, sizeof(inarg));
784 inarg.oldnodeid = get_node_id(inode);
785 req->in.h.opcode = FUSE_LINK;
786 req->in.numargs = 2;
787 req->in.args[0].size = sizeof(inarg);
788 req->in.args[0].value = &inarg;
789 req->in.args[1].size = newent->d_name.len + 1;
790 req->in.args[1].value = newent->d_name.name;
791 err = create_new_entry(fc, req, newdir, newent, inode->i_mode);
792 /* Contrary to "normal" filesystems it can happen that link
793 makes two "logical" inodes point to the same "physical"
794 inode. We invalidate the attributes of the old one, so it
795 will reflect changes in the backing inode (link count,
796 etc.)
797 */
798 if (!err) {
799 struct fuse_inode *fi = get_fuse_inode(inode);
800
801 spin_lock(&fc->lock);
802 fi->attr_version = ++fc->attr_version;
803 inc_nlink(inode);
804 spin_unlock(&fc->lock);
805 fuse_invalidate_attr(inode);
806 } else if (err == -EINTR) {
807 fuse_invalidate_attr(inode);
808 }
809 return err;
810 }
811
812 static void fuse_fillattr(struct inode *inode, struct fuse_attr *attr,
813 struct kstat *stat)
814 {
815 unsigned int blkbits;
816
817 stat->dev = inode->i_sb->s_dev;
818 stat->ino = attr->ino;
819 stat->mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
820 stat->nlink = attr->nlink;
821 stat->uid = make_kuid(&init_user_ns, attr->uid);
822 stat->gid = make_kgid(&init_user_ns, attr->gid);
823 stat->rdev = inode->i_rdev;
824 stat->atime.tv_sec = attr->atime;
825 stat->atime.tv_nsec = attr->atimensec;
826 stat->mtime.tv_sec = attr->mtime;
827 stat->mtime.tv_nsec = attr->mtimensec;
828 stat->ctime.tv_sec = attr->ctime;
829 stat->ctime.tv_nsec = attr->ctimensec;
830 stat->size = attr->size;
831 stat->blocks = attr->blocks;
832
833 if (attr->blksize != 0)
834 blkbits = ilog2(attr->blksize);
835 else
836 blkbits = inode->i_sb->s_blocksize_bits;
837
838 stat->blksize = 1 << blkbits;
839 }
840
841 static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
842 struct file *file)
843 {
844 int err;
845 struct fuse_getattr_in inarg;
846 struct fuse_attr_out outarg;
847 struct fuse_conn *fc = get_fuse_conn(inode);
848 struct fuse_req *req;
849 u64 attr_version;
850
851 req = fuse_get_req(fc);
852 if (IS_ERR(req))
853 return PTR_ERR(req);
854
855 attr_version = fuse_get_attr_version(fc);
856
857 memset(&inarg, 0, sizeof(inarg));
858 memset(&outarg, 0, sizeof(outarg));
859 /* Directories have separate file-handle space */
860 if (file && S_ISREG(inode->i_mode)) {
861 struct fuse_file *ff = file->private_data;
862
863 inarg.getattr_flags |= FUSE_GETATTR_FH;
864 inarg.fh = ff->fh;
865 }
866 req->in.h.opcode = FUSE_GETATTR;
867 req->in.h.nodeid = get_node_id(inode);
868 req->in.numargs = 1;
869 req->in.args[0].size = sizeof(inarg);
870 req->in.args[0].value = &inarg;
871 req->out.numargs = 1;
872 if (fc->minor < 9)
873 req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
874 else
875 req->out.args[0].size = sizeof(outarg);
876 req->out.args[0].value = &outarg;
877 fuse_request_send(fc, req);
878 err = req->out.h.error;
879 fuse_put_request(fc, req);
880 if (!err) {
881 if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
882 make_bad_inode(inode);
883 err = -EIO;
884 } else {
885 fuse_change_attributes(inode, &outarg.attr,
886 attr_timeout(&outarg),
887 attr_version);
888 if (stat)
889 fuse_fillattr(inode, &outarg.attr, stat);
890 }
891 }
892 return err;
893 }
894
895 int fuse_update_attributes(struct inode *inode, struct kstat *stat,
896 struct file *file, bool *refreshed)
897 {
898 struct fuse_inode *fi = get_fuse_inode(inode);
899 int err;
900 bool r;
901
902 if (fi->i_time < get_jiffies_64()) {
903 r = true;
904 err = fuse_do_getattr(inode, stat, file);
905 } else {
906 r = false;
907 err = 0;
908 if (stat) {
909 generic_fillattr(inode, stat);
910 stat->mode = fi->orig_i_mode;
911 stat->ino = fi->orig_ino;
912 }
913 }
914
915 if (refreshed != NULL)
916 *refreshed = r;
917
918 return err;
919 }
920
921 int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
922 u64 child_nodeid, struct qstr *name)
923 {
924 int err = -ENOTDIR;
925 struct inode *parent;
926 struct dentry *dir;
927 struct dentry *entry;
928
929 parent = ilookup5(sb, parent_nodeid, fuse_inode_eq, &parent_nodeid);
930 if (!parent)
931 return -ENOENT;
932
933 mutex_lock(&parent->i_mutex);
934 if (!S_ISDIR(parent->i_mode))
935 goto unlock;
936
937 err = -ENOENT;
938 dir = d_find_alias(parent);
939 if (!dir)
940 goto unlock;
941
942 entry = d_lookup(dir, name);
943 dput(dir);
944 if (!entry)
945 goto unlock;
946
947 fuse_invalidate_attr(parent);
948 fuse_invalidate_entry(entry);
949
950 if (child_nodeid != 0 && entry->d_inode) {
951 mutex_lock(&entry->d_inode->i_mutex);
952 if (get_node_id(entry->d_inode) != child_nodeid) {
953 err = -ENOENT;
954 goto badentry;
955 }
956 if (d_mountpoint(entry)) {
957 err = -EBUSY;
958 goto badentry;
959 }
960 if (S_ISDIR(entry->d_inode->i_mode)) {
961 shrink_dcache_parent(entry);
962 if (!simple_empty(entry)) {
963 err = -ENOTEMPTY;
964 goto badentry;
965 }
966 entry->d_inode->i_flags |= S_DEAD;
967 }
968 dont_mount(entry);
969 clear_nlink(entry->d_inode);
970 err = 0;
971 badentry:
972 mutex_unlock(&entry->d_inode->i_mutex);
973 if (!err)
974 d_delete(entry);
975 } else {
976 err = 0;
977 }
978 dput(entry);
979
980 unlock:
981 mutex_unlock(&parent->i_mutex);
982 iput(parent);
983 return err;
984 }
985
986 /*
987 * Calling into a user-controlled filesystem gives the filesystem
988 * daemon ptrace-like capabilities over the requester process. This
989 * means, that the filesystem daemon is able to record the exact
990 * filesystem operations performed, and can also control the behavior
991 * of the requester process in otherwise impossible ways. For example
992 * it can delay the operation for arbitrary length of time allowing
993 * DoS against the requester.
994 *
995 * For this reason only those processes can call into the filesystem,
996 * for which the owner of the mount has ptrace privilege. This
997 * excludes processes started by other users, suid or sgid processes.
998 */
999 int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task)
1000 {
1001 const struct cred *cred;
1002 int ret;
1003
1004 if (fc->flags & FUSE_ALLOW_OTHER)
1005 return 1;
1006
1007 rcu_read_lock();
1008 ret = 0;
1009 cred = __task_cred(task);
1010 if (uid_eq(cred->euid, fc->user_id) &&
1011 uid_eq(cred->suid, fc->user_id) &&
1012 uid_eq(cred->uid, fc->user_id) &&
1013 gid_eq(cred->egid, fc->group_id) &&
1014 gid_eq(cred->sgid, fc->group_id) &&
1015 gid_eq(cred->gid, fc->group_id))
1016 ret = 1;
1017 rcu_read_unlock();
1018
1019 return ret;
1020 }
1021
1022 static int fuse_access(struct inode *inode, int mask)
1023 {
1024 struct fuse_conn *fc = get_fuse_conn(inode);
1025 struct fuse_req *req;
1026 struct fuse_access_in inarg;
1027 int err;
1028
1029 if (fc->no_access)
1030 return 0;
1031
1032 req = fuse_get_req(fc);
1033 if (IS_ERR(req))
1034 return PTR_ERR(req);
1035
1036 memset(&inarg, 0, sizeof(inarg));
1037 inarg.mask = mask & (MAY_READ | MAY_WRITE | MAY_EXEC);
1038 req->in.h.opcode = FUSE_ACCESS;
1039 req->in.h.nodeid = get_node_id(inode);
1040 req->in.numargs = 1;
1041 req->in.args[0].size = sizeof(inarg);
1042 req->in.args[0].value = &inarg;
1043 fuse_request_send(fc, req);
1044 err = req->out.h.error;
1045 fuse_put_request(fc, req);
1046 if (err == -ENOSYS) {
1047 fc->no_access = 1;
1048 err = 0;
1049 }
1050 return err;
1051 }
1052
1053 static int fuse_perm_getattr(struct inode *inode, int mask)
1054 {
1055 if (mask & MAY_NOT_BLOCK)
1056 return -ECHILD;
1057
1058 return fuse_do_getattr(inode, NULL, NULL);
1059 }
1060
1061 /*
1062 * Check permission. The two basic access models of FUSE are:
1063 *
1064 * 1) Local access checking ('default_permissions' mount option) based
1065 * on file mode. This is the plain old disk filesystem permission
1066 * modell.
1067 *
1068 * 2) "Remote" access checking, where server is responsible for
1069 * checking permission in each inode operation. An exception to this
1070 * is if ->permission() was invoked from sys_access() in which case an
1071 * access request is sent. Execute permission is still checked
1072 * locally based on file mode.
1073 */
1074 static int fuse_permission(struct inode *inode, int mask)
1075 {
1076 struct fuse_conn *fc = get_fuse_conn(inode);
1077 bool refreshed = false;
1078 int err = 0;
1079
1080 if (!fuse_allow_task(fc, current))
1081 return -EACCES;
1082
1083 /*
1084 * If attributes are needed, refresh them before proceeding
1085 */
1086 if ((fc->flags & FUSE_DEFAULT_PERMISSIONS) ||
1087 ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))) {
1088 struct fuse_inode *fi = get_fuse_inode(inode);
1089
1090 if (fi->i_time < get_jiffies_64()) {
1091 refreshed = true;
1092
1093 err = fuse_perm_getattr(inode, mask);
1094 if (err)
1095 return err;
1096 }
1097 }
1098
1099 if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
1100 err = generic_permission(inode, mask);
1101
1102 /* If permission is denied, try to refresh file
1103 attributes. This is also needed, because the root
1104 node will at first have no permissions */
1105 if (err == -EACCES && !refreshed) {
1106 err = fuse_perm_getattr(inode, mask);
1107 if (!err)
1108 err = generic_permission(inode, mask);
1109 }
1110
1111 /* Note: the opposite of the above test does not
1112 exist. So if permissions are revoked this won't be
1113 noticed immediately, only after the attribute
1114 timeout has expired */
1115 } else if (mask & (MAY_ACCESS | MAY_CHDIR)) {
1116 if (mask & MAY_NOT_BLOCK)
1117 return -ECHILD;
1118
1119 err = fuse_access(inode, mask);
1120 } else if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) {
1121 if (!(inode->i_mode & S_IXUGO)) {
1122 if (refreshed)
1123 return -EACCES;
1124
1125 err = fuse_perm_getattr(inode, mask);
1126 if (!err && !(inode->i_mode & S_IXUGO))
1127 return -EACCES;
1128 }
1129 }
1130 return err;
1131 }
1132
1133 static int parse_dirfile(char *buf, size_t nbytes, struct file *file,
1134 void *dstbuf, filldir_t filldir)
1135 {
1136 while (nbytes >= FUSE_NAME_OFFSET) {
1137 struct fuse_dirent *dirent = (struct fuse_dirent *) buf;
1138 size_t reclen = FUSE_DIRENT_SIZE(dirent);
1139 int over;
1140 if (!dirent->namelen || dirent->namelen > FUSE_NAME_MAX)
1141 return -EIO;
1142 if (reclen > nbytes)
1143 break;
1144
1145 over = filldir(dstbuf, dirent->name, dirent->namelen,
1146 file->f_pos, dirent->ino, dirent->type);
1147 if (over)
1148 break;
1149
1150 buf += reclen;
1151 nbytes -= reclen;
1152 file->f_pos = dirent->off;
1153 }
1154
1155 return 0;
1156 }
1157
1158 static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
1159 {
1160 int err;
1161 size_t nbytes;
1162 struct page *page;
1163 struct inode *inode = file_inode(file);
1164 struct fuse_conn *fc = get_fuse_conn(inode);
1165 struct fuse_req *req;
1166
1167 if (is_bad_inode(inode))
1168 return -EIO;
1169
1170 req = fuse_get_req(fc);
1171 if (IS_ERR(req))
1172 return PTR_ERR(req);
1173
1174 page = alloc_page(GFP_KERNEL);
1175 if (!page) {
1176 fuse_put_request(fc, req);
1177 return -ENOMEM;
1178 }
1179 req->out.argpages = 1;
1180 req->num_pages = 1;
1181 req->pages[0] = page;
1182 fuse_read_fill(req, file, file->f_pos, PAGE_SIZE, FUSE_READDIR);
1183 fuse_request_send(fc, req);
1184 nbytes = req->out.args[0].size;
1185 err = req->out.h.error;
1186 fuse_put_request(fc, req);
1187 if (!err)
1188 err = parse_dirfile(page_address(page), nbytes, file, dstbuf,
1189 filldir);
1190
1191 __free_page(page);
1192 fuse_invalidate_attr(inode); /* atime changed */
1193 return err;
1194 }
1195
1196 static char *read_link(struct dentry *dentry)
1197 {
1198 struct inode *inode = dentry->d_inode;
1199 struct fuse_conn *fc = get_fuse_conn(inode);
1200 struct fuse_req *req = fuse_get_req(fc);
1201 char *link;
1202
1203 if (IS_ERR(req))
1204 return ERR_CAST(req);
1205
1206 link = (char *) __get_free_page(GFP_KERNEL);
1207 if (!link) {
1208 link = ERR_PTR(-ENOMEM);
1209 goto out;
1210 }
1211 req->in.h.opcode = FUSE_READLINK;
1212 req->in.h.nodeid = get_node_id(inode);
1213 req->out.argvar = 1;
1214 req->out.numargs = 1;
1215 req->out.args[0].size = PAGE_SIZE - 1;
1216 req->out.args[0].value = link;
1217 fuse_request_send(fc, req);
1218 if (req->out.h.error) {
1219 free_page((unsigned long) link);
1220 link = ERR_PTR(req->out.h.error);
1221 } else
1222 link[req->out.args[0].size] = '\0';
1223 out:
1224 fuse_put_request(fc, req);
1225 fuse_invalidate_attr(inode); /* atime changed */
1226 return link;
1227 }
1228
1229 static void free_link(char *link)
1230 {
1231 if (!IS_ERR(link))
1232 free_page((unsigned long) link);
1233 }
1234
1235 static void *fuse_follow_link(struct dentry *dentry, struct nameidata *nd)
1236 {
1237 nd_set_link(nd, read_link(dentry));
1238 return NULL;
1239 }
1240
1241 static void fuse_put_link(struct dentry *dentry, struct nameidata *nd, void *c)
1242 {
1243 free_link(nd_get_link(nd));
1244 }
1245
1246 static int fuse_dir_open(struct inode *inode, struct file *file)
1247 {
1248 return fuse_open_common(inode, file, true);
1249 }
1250
1251 static int fuse_dir_release(struct inode *inode, struct file *file)
1252 {
1253 fuse_release_common(file, FUSE_RELEASEDIR);
1254
1255 return 0;
1256 }
1257
1258 static int fuse_dir_fsync(struct file *file, loff_t start, loff_t end,
1259 int datasync)
1260 {
1261 return fuse_fsync_common(file, start, end, datasync, 1);
1262 }
1263
1264 static long fuse_dir_ioctl(struct file *file, unsigned int cmd,
1265 unsigned long arg)
1266 {
1267 struct fuse_conn *fc = get_fuse_conn(file->f_mapping->host);
1268
1269 /* FUSE_IOCTL_DIR only supported for API version >= 7.18 */
1270 if (fc->minor < 18)
1271 return -ENOTTY;
1272
1273 return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_DIR);
1274 }
1275
1276 static long fuse_dir_compat_ioctl(struct file *file, unsigned int cmd,
1277 unsigned long arg)
1278 {
1279 struct fuse_conn *fc = get_fuse_conn(file->f_mapping->host);
1280
1281 if (fc->minor < 18)
1282 return -ENOTTY;
1283
1284 return fuse_ioctl_common(file, cmd, arg,
1285 FUSE_IOCTL_COMPAT | FUSE_IOCTL_DIR);
1286 }
1287
1288 static bool update_mtime(unsigned ivalid)
1289 {
1290 /* Always update if mtime is explicitly set */
1291 if (ivalid & ATTR_MTIME_SET)
1292 return true;
1293
1294 /* If it's an open(O_TRUNC) or an ftruncate(), don't update */
1295 if ((ivalid & ATTR_SIZE) && (ivalid & (ATTR_OPEN | ATTR_FILE)))
1296 return false;
1297
1298 /* In all other cases update */
1299 return true;
1300 }
1301
1302 static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg)
1303 {
1304 unsigned ivalid = iattr->ia_valid;
1305
1306 if (ivalid & ATTR_MODE)
1307 arg->valid |= FATTR_MODE, arg->mode = iattr->ia_mode;
1308 if (ivalid & ATTR_UID)
1309 arg->valid |= FATTR_UID, arg->uid = from_kuid(&init_user_ns, iattr->ia_uid);
1310 if (ivalid & ATTR_GID)
1311 arg->valid |= FATTR_GID, arg->gid = from_kgid(&init_user_ns, iattr->ia_gid);
1312 if (ivalid & ATTR_SIZE)
1313 arg->valid |= FATTR_SIZE, arg->size = iattr->ia_size;
1314 if (ivalid & ATTR_ATIME) {
1315 arg->valid |= FATTR_ATIME;
1316 arg->atime = iattr->ia_atime.tv_sec;
1317 arg->atimensec = iattr->ia_atime.tv_nsec;
1318 if (!(ivalid & ATTR_ATIME_SET))
1319 arg->valid |= FATTR_ATIME_NOW;
1320 }
1321 if ((ivalid & ATTR_MTIME) && update_mtime(ivalid)) {
1322 arg->valid |= FATTR_MTIME;
1323 arg->mtime = iattr->ia_mtime.tv_sec;
1324 arg->mtimensec = iattr->ia_mtime.tv_nsec;
1325 if (!(ivalid & ATTR_MTIME_SET))
1326 arg->valid |= FATTR_MTIME_NOW;
1327 }
1328 }
1329
1330 /*
1331 * Prevent concurrent writepages on inode
1332 *
1333 * This is done by adding a negative bias to the inode write counter
1334 * and waiting for all pending writes to finish.
1335 */
1336 void fuse_set_nowrite(struct inode *inode)
1337 {
1338 struct fuse_conn *fc = get_fuse_conn(inode);
1339 struct fuse_inode *fi = get_fuse_inode(inode);
1340
1341 BUG_ON(!mutex_is_locked(&inode->i_mutex));
1342
1343 spin_lock(&fc->lock);
1344 BUG_ON(fi->writectr < 0);
1345 fi->writectr += FUSE_NOWRITE;
1346 spin_unlock(&fc->lock);
1347 wait_event(fi->page_waitq, fi->writectr == FUSE_NOWRITE);
1348 }
1349
1350 /*
1351 * Allow writepages on inode
1352 *
1353 * Remove the bias from the writecounter and send any queued
1354 * writepages.
1355 */
1356 static void __fuse_release_nowrite(struct inode *inode)
1357 {
1358 struct fuse_inode *fi = get_fuse_inode(inode);
1359
1360 BUG_ON(fi->writectr != FUSE_NOWRITE);
1361 fi->writectr = 0;
1362 fuse_flush_writepages(inode);
1363 }
1364
1365 void fuse_release_nowrite(struct inode *inode)
1366 {
1367 struct fuse_conn *fc = get_fuse_conn(inode);
1368
1369 spin_lock(&fc->lock);
1370 __fuse_release_nowrite(inode);
1371 spin_unlock(&fc->lock);
1372 }
1373
1374 /*
1375 * Set attributes, and at the same time refresh them.
1376 *
1377 * Truncation is slightly complicated, because the 'truncate' request
1378 * may fail, in which case we don't want to touch the mapping.
1379 * vmtruncate() doesn't allow for this case, so do the rlimit checking
1380 * and the actual truncation by hand.
1381 */
1382 static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
1383 struct file *file)
1384 {
1385 struct inode *inode = entry->d_inode;
1386 struct fuse_conn *fc = get_fuse_conn(inode);
1387 struct fuse_req *req;
1388 struct fuse_setattr_in inarg;
1389 struct fuse_attr_out outarg;
1390 bool is_truncate = false;
1391 loff_t oldsize;
1392 int err;
1393
1394 if (!fuse_allow_task(fc, current))
1395 return -EACCES;
1396
1397 if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
1398 attr->ia_valid |= ATTR_FORCE;
1399
1400 err = inode_change_ok(inode, attr);
1401 if (err)
1402 return err;
1403
1404 if (attr->ia_valid & ATTR_OPEN) {
1405 if (fc->atomic_o_trunc)
1406 return 0;
1407 file = NULL;
1408 }
1409
1410 if (attr->ia_valid & ATTR_SIZE)
1411 is_truncate = true;
1412
1413 req = fuse_get_req(fc);
1414 if (IS_ERR(req))
1415 return PTR_ERR(req);
1416
1417 if (is_truncate)
1418 fuse_set_nowrite(inode);
1419
1420 memset(&inarg, 0, sizeof(inarg));
1421 memset(&outarg, 0, sizeof(outarg));
1422 iattr_to_fattr(attr, &inarg);
1423 if (file) {
1424 struct fuse_file *ff = file->private_data;
1425 inarg.valid |= FATTR_FH;
1426 inarg.fh = ff->fh;
1427 }
1428 if (attr->ia_valid & ATTR_SIZE) {
1429 /* For mandatory locking in truncate */
1430 inarg.valid |= FATTR_LOCKOWNER;
1431 inarg.lock_owner = fuse_lock_owner_id(fc, current->files);
1432 }
1433 req->in.h.opcode = FUSE_SETATTR;
1434 req->in.h.nodeid = get_node_id(inode);
1435 req->in.numargs = 1;
1436 req->in.args[0].size = sizeof(inarg);
1437 req->in.args[0].value = &inarg;
1438 req->out.numargs = 1;
1439 if (fc->minor < 9)
1440 req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
1441 else
1442 req->out.args[0].size = sizeof(outarg);
1443 req->out.args[0].value = &outarg;
1444 fuse_request_send(fc, req);
1445 err = req->out.h.error;
1446 fuse_put_request(fc, req);
1447 if (err) {
1448 if (err == -EINTR)
1449 fuse_invalidate_attr(inode);
1450 goto error;
1451 }
1452
1453 if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
1454 make_bad_inode(inode);
1455 err = -EIO;
1456 goto error;
1457 }
1458
1459 spin_lock(&fc->lock);
1460 fuse_change_attributes_common(inode, &outarg.attr,
1461 attr_timeout(&outarg));
1462 oldsize = inode->i_size;
1463 i_size_write(inode, outarg.attr.size);
1464
1465 if (is_truncate) {
1466 /* NOTE: this may release/reacquire fc->lock */
1467 __fuse_release_nowrite(inode);
1468 }
1469 spin_unlock(&fc->lock);
1470
1471 /*
1472 * Only call invalidate_inode_pages2() after removing
1473 * FUSE_NOWRITE, otherwise fuse_launder_page() would deadlock.
1474 */
1475 if (S_ISREG(inode->i_mode) && oldsize != outarg.attr.size) {
1476 truncate_pagecache(inode, oldsize, outarg.attr.size);
1477 invalidate_inode_pages2(inode->i_mapping);
1478 }
1479
1480 return 0;
1481
1482 error:
1483 if (is_truncate)
1484 fuse_release_nowrite(inode);
1485
1486 return err;
1487 }
1488
1489 static int fuse_setattr(struct dentry *entry, struct iattr *attr)
1490 {
1491 if (attr->ia_valid & ATTR_FILE)
1492 return fuse_do_setattr(entry, attr, attr->ia_file);
1493 else
1494 return fuse_do_setattr(entry, attr, NULL);
1495 }
1496
1497 static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
1498 struct kstat *stat)
1499 {
1500 struct inode *inode = entry->d_inode;
1501 struct fuse_conn *fc = get_fuse_conn(inode);
1502
1503 if (!fuse_allow_task(fc, current))
1504 return -EACCES;
1505
1506 return fuse_update_attributes(inode, stat, NULL, NULL);
1507 }
1508
1509 static int fuse_setxattr(struct dentry *entry, const char *name,
1510 const void *value, size_t size, int flags)
1511 {
1512 struct inode *inode = entry->d_inode;
1513 struct fuse_conn *fc = get_fuse_conn(inode);
1514 struct fuse_req *req;
1515 struct fuse_setxattr_in inarg;
1516 int err;
1517
1518 if (fc->no_setxattr)
1519 return -EOPNOTSUPP;
1520
1521 req = fuse_get_req(fc);
1522 if (IS_ERR(req))
1523 return PTR_ERR(req);
1524
1525 memset(&inarg, 0, sizeof(inarg));
1526 inarg.size = size;
1527 inarg.flags = flags;
1528 req->in.h.opcode = FUSE_SETXATTR;
1529 req->in.h.nodeid = get_node_id(inode);
1530 req->in.numargs = 3;
1531 req->in.args[0].size = sizeof(inarg);
1532 req->in.args[0].value = &inarg;
1533 req->in.args[1].size = strlen(name) + 1;
1534 req->in.args[1].value = name;
1535 req->in.args[2].size = size;
1536 req->in.args[2].value = value;
1537 fuse_request_send(fc, req);
1538 err = req->out.h.error;
1539 fuse_put_request(fc, req);
1540 if (err == -ENOSYS) {
1541 fc->no_setxattr = 1;
1542 err = -EOPNOTSUPP;
1543 }
1544 return err;
1545 }
1546
1547 static ssize_t fuse_getxattr(struct dentry *entry, const char *name,
1548 void *value, size_t size)
1549 {
1550 struct inode *inode = entry->d_inode;
1551 struct fuse_conn *fc = get_fuse_conn(inode);
1552 struct fuse_req *req;
1553 struct fuse_getxattr_in inarg;
1554 struct fuse_getxattr_out outarg;
1555 ssize_t ret;
1556
1557 if (fc->no_getxattr)
1558 return -EOPNOTSUPP;
1559
1560 req = fuse_get_req(fc);
1561 if (IS_ERR(req))
1562 return PTR_ERR(req);
1563
1564 memset(&inarg, 0, sizeof(inarg));
1565 inarg.size = size;
1566 req->in.h.opcode = FUSE_GETXATTR;
1567 req->in.h.nodeid = get_node_id(inode);
1568 req->in.numargs = 2;
1569 req->in.args[0].size = sizeof(inarg);
1570 req->in.args[0].value = &inarg;
1571 req->in.args[1].size = strlen(name) + 1;
1572 req->in.args[1].value = name;
1573 /* This is really two different operations rolled into one */
1574 req->out.numargs = 1;
1575 if (size) {
1576 req->out.argvar = 1;
1577 req->out.args[0].size = size;
1578 req->out.args[0].value = value;
1579 } else {
1580 req->out.args[0].size = sizeof(outarg);
1581 req->out.args[0].value = &outarg;
1582 }
1583 fuse_request_send(fc, req);
1584 ret = req->out.h.error;
1585 if (!ret)
1586 ret = size ? req->out.args[0].size : outarg.size;
1587 else {
1588 if (ret == -ENOSYS) {
1589 fc->no_getxattr = 1;
1590 ret = -EOPNOTSUPP;
1591 }
1592 }
1593 fuse_put_request(fc, req);
1594 return ret;
1595 }
1596
1597 static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
1598 {
1599 struct inode *inode = entry->d_inode;
1600 struct fuse_conn *fc = get_fuse_conn(inode);
1601 struct fuse_req *req;
1602 struct fuse_getxattr_in inarg;
1603 struct fuse_getxattr_out outarg;
1604 ssize_t ret;
1605
1606 if (!fuse_allow_task(fc, current))
1607 return -EACCES;
1608
1609 if (fc->no_listxattr)
1610 return -EOPNOTSUPP;
1611
1612 req = fuse_get_req(fc);
1613 if (IS_ERR(req))
1614 return PTR_ERR(req);
1615
1616 memset(&inarg, 0, sizeof(inarg));
1617 inarg.size = size;
1618 req->in.h.opcode = FUSE_LISTXATTR;
1619 req->in.h.nodeid = get_node_id(inode);
1620 req->in.numargs = 1;
1621 req->in.args[0].size = sizeof(inarg);
1622 req->in.args[0].value = &inarg;
1623 /* This is really two different operations rolled into one */
1624 req->out.numargs = 1;
1625 if (size) {
1626 req->out.argvar = 1;
1627 req->out.args[0].size = size;
1628 req->out.args[0].value = list;
1629 } else {
1630 req->out.args[0].size = sizeof(outarg);
1631 req->out.args[0].value = &outarg;
1632 }
1633 fuse_request_send(fc, req);
1634 ret = req->out.h.error;
1635 if (!ret)
1636 ret = size ? req->out.args[0].size : outarg.size;
1637 else {
1638 if (ret == -ENOSYS) {
1639 fc->no_listxattr = 1;
1640 ret = -EOPNOTSUPP;
1641 }
1642 }
1643 fuse_put_request(fc, req);
1644 return ret;
1645 }
1646
1647 static int fuse_removexattr(struct dentry *entry, const char *name)
1648 {
1649 struct inode *inode = entry->d_inode;
1650 struct fuse_conn *fc = get_fuse_conn(inode);
1651 struct fuse_req *req;
1652 int err;
1653
1654 if (fc->no_removexattr)
1655 return -EOPNOTSUPP;
1656
1657 req = fuse_get_req(fc);
1658 if (IS_ERR(req))
1659 return PTR_ERR(req);
1660
1661 req->in.h.opcode = FUSE_REMOVEXATTR;
1662 req->in.h.nodeid = get_node_id(inode);
1663 req->in.numargs = 1;
1664 req->in.args[0].size = strlen(name) + 1;
1665 req->in.args[0].value = name;
1666 fuse_request_send(fc, req);
1667 err = req->out.h.error;
1668 fuse_put_request(fc, req);
1669 if (err == -ENOSYS) {
1670 fc->no_removexattr = 1;
1671 err = -EOPNOTSUPP;
1672 }
1673 return err;
1674 }
1675
1676 static const struct inode_operations fuse_dir_inode_operations = {
1677 .lookup = fuse_lookup,
1678 .mkdir = fuse_mkdir,
1679 .symlink = fuse_symlink,
1680 .unlink = fuse_unlink,
1681 .rmdir = fuse_rmdir,
1682 .rename = fuse_rename,
1683 .link = fuse_link,
1684 .setattr = fuse_setattr,
1685 .create = fuse_create,
1686 .atomic_open = fuse_atomic_open,
1687 .mknod = fuse_mknod,
1688 .permission = fuse_permission,
1689 .getattr = fuse_getattr,
1690 .setxattr = fuse_setxattr,
1691 .getxattr = fuse_getxattr,
1692 .listxattr = fuse_listxattr,
1693 .removexattr = fuse_removexattr,
1694 };
1695
1696 static const struct file_operations fuse_dir_operations = {
1697 .llseek = generic_file_llseek,
1698 .read = generic_read_dir,
1699 .readdir = fuse_readdir,
1700 .open = fuse_dir_open,
1701 .release = fuse_dir_release,
1702 .fsync = fuse_dir_fsync,
1703 .unlocked_ioctl = fuse_dir_ioctl,
1704 .compat_ioctl = fuse_dir_compat_ioctl,
1705 };
1706
1707 static const struct inode_operations fuse_common_inode_operations = {
1708 .setattr = fuse_setattr,
1709 .permission = fuse_permission,
1710 .getattr = fuse_getattr,
1711 .setxattr = fuse_setxattr,
1712 .getxattr = fuse_getxattr,
1713 .listxattr = fuse_listxattr,
1714 .removexattr = fuse_removexattr,
1715 };
1716
1717 static const struct inode_operations fuse_symlink_inode_operations = {
1718 .setattr = fuse_setattr,
1719 .follow_link = fuse_follow_link,
1720 .put_link = fuse_put_link,
1721 .readlink = generic_readlink,
1722 .getattr = fuse_getattr,
1723 .setxattr = fuse_setxattr,
1724 .getxattr = fuse_getxattr,
1725 .listxattr = fuse_listxattr,
1726 .removexattr = fuse_removexattr,
1727 };
1728
1729 void fuse_init_common(struct inode *inode)
1730 {
1731 inode->i_op = &fuse_common_inode_operations;
1732 }
1733
1734 void fuse_init_dir(struct inode *inode)
1735 {
1736 inode->i_op = &fuse_dir_inode_operations;
1737 inode->i_fop = &fuse_dir_operations;
1738 }
1739
1740 void fuse_init_symlink(struct inode *inode)
1741 {
1742 inode->i_op = &fuse_symlink_inode_operations;
1743 }