fuse: Get rid of bdi_initialized
[sfrench/cifs-2.6.git] / fs / fuse / inode.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/slab.h>
13 #include <linux/file.h>
14 #include <linux/seq_file.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/parser.h>
19 #include <linux/statfs.h>
20 #include <linux/random.h>
21 #include <linux/sched.h>
22 #include <linux/exportfs.h>
23 #include <linux/posix_acl.h>
24
25 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
26 MODULE_DESCRIPTION("Filesystem in Userspace");
27 MODULE_LICENSE("GPL");
28
29 static struct kmem_cache *fuse_inode_cachep;
30 struct list_head fuse_conn_list;
31 DEFINE_MUTEX(fuse_mutex);
32
33 static int set_global_limit(const char *val, struct kernel_param *kp);
34
35 unsigned max_user_bgreq;
36 module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
37                   &max_user_bgreq, 0644);
38 __MODULE_PARM_TYPE(max_user_bgreq, "uint");
39 MODULE_PARM_DESC(max_user_bgreq,
40  "Global limit for the maximum number of backgrounded requests an "
41  "unprivileged user can set");
42
43 unsigned max_user_congthresh;
44 module_param_call(max_user_congthresh, set_global_limit, param_get_uint,
45                   &max_user_congthresh, 0644);
46 __MODULE_PARM_TYPE(max_user_congthresh, "uint");
47 MODULE_PARM_DESC(max_user_congthresh,
48  "Global limit for the maximum congestion threshold an "
49  "unprivileged user can set");
50
51 #define FUSE_SUPER_MAGIC 0x65735546
52
53 #define FUSE_DEFAULT_BLKSIZE 512
54
55 /** Maximum number of outstanding background requests */
56 #define FUSE_DEFAULT_MAX_BACKGROUND 12
57
58 /** Congestion starts at 75% of maximum */
59 #define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4)
60
61 struct fuse_mount_data {
62         int fd;
63         unsigned rootmode;
64         kuid_t user_id;
65         kgid_t group_id;
66         unsigned fd_present:1;
67         unsigned rootmode_present:1;
68         unsigned user_id_present:1;
69         unsigned group_id_present:1;
70         unsigned default_permissions:1;
71         unsigned allow_other:1;
72         unsigned max_read;
73         unsigned blksize;
74 };
75
76 struct fuse_forget_link *fuse_alloc_forget(void)
77 {
78         return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL);
79 }
80
81 static struct inode *fuse_alloc_inode(struct super_block *sb)
82 {
83         struct inode *inode;
84         struct fuse_inode *fi;
85
86         inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
87         if (!inode)
88                 return NULL;
89
90         fi = get_fuse_inode(inode);
91         fi->i_time = 0;
92         fi->nodeid = 0;
93         fi->nlookup = 0;
94         fi->attr_version = 0;
95         fi->writectr = 0;
96         fi->orig_ino = 0;
97         fi->state = 0;
98         INIT_LIST_HEAD(&fi->write_files);
99         INIT_LIST_HEAD(&fi->queued_writes);
100         INIT_LIST_HEAD(&fi->writepages);
101         init_waitqueue_head(&fi->page_waitq);
102         mutex_init(&fi->mutex);
103         fi->forget = fuse_alloc_forget();
104         if (!fi->forget) {
105                 kmem_cache_free(fuse_inode_cachep, inode);
106                 return NULL;
107         }
108
109         return inode;
110 }
111
112 static void fuse_i_callback(struct rcu_head *head)
113 {
114         struct inode *inode = container_of(head, struct inode, i_rcu);
115         kmem_cache_free(fuse_inode_cachep, inode);
116 }
117
118 static void fuse_destroy_inode(struct inode *inode)
119 {
120         struct fuse_inode *fi = get_fuse_inode(inode);
121         BUG_ON(!list_empty(&fi->write_files));
122         BUG_ON(!list_empty(&fi->queued_writes));
123         mutex_destroy(&fi->mutex);
124         kfree(fi->forget);
125         call_rcu(&inode->i_rcu, fuse_i_callback);
126 }
127
128 static void fuse_evict_inode(struct inode *inode)
129 {
130         truncate_inode_pages_final(&inode->i_data);
131         clear_inode(inode);
132         if (inode->i_sb->s_flags & MS_ACTIVE) {
133                 struct fuse_conn *fc = get_fuse_conn(inode);
134                 struct fuse_inode *fi = get_fuse_inode(inode);
135                 fuse_queue_forget(fc, fi->forget, fi->nodeid, fi->nlookup);
136                 fi->forget = NULL;
137         }
138 }
139
140 static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
141 {
142         sync_filesystem(sb);
143         if (*flags & MS_MANDLOCK)
144                 return -EINVAL;
145
146         return 0;
147 }
148
149 /*
150  * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
151  * so that it will fit.
152  */
153 static ino_t fuse_squash_ino(u64 ino64)
154 {
155         ino_t ino = (ino_t) ino64;
156         if (sizeof(ino_t) < sizeof(u64))
157                 ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8;
158         return ino;
159 }
160
161 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
162                                    u64 attr_valid)
163 {
164         struct fuse_conn *fc = get_fuse_conn(inode);
165         struct fuse_inode *fi = get_fuse_inode(inode);
166
167         fi->attr_version = ++fc->attr_version;
168         fi->i_time = attr_valid;
169
170         inode->i_ino     = fuse_squash_ino(attr->ino);
171         inode->i_mode    = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
172         set_nlink(inode, attr->nlink);
173         inode->i_uid     = make_kuid(&init_user_ns, attr->uid);
174         inode->i_gid     = make_kgid(&init_user_ns, attr->gid);
175         inode->i_blocks  = attr->blocks;
176         inode->i_atime.tv_sec   = attr->atime;
177         inode->i_atime.tv_nsec  = attr->atimensec;
178         /* mtime from server may be stale due to local buffered write */
179         if (!fc->writeback_cache || !S_ISREG(inode->i_mode)) {
180                 inode->i_mtime.tv_sec   = attr->mtime;
181                 inode->i_mtime.tv_nsec  = attr->mtimensec;
182                 inode->i_ctime.tv_sec   = attr->ctime;
183                 inode->i_ctime.tv_nsec  = attr->ctimensec;
184         }
185
186         if (attr->blksize != 0)
187                 inode->i_blkbits = ilog2(attr->blksize);
188         else
189                 inode->i_blkbits = inode->i_sb->s_blocksize_bits;
190
191         /*
192          * Don't set the sticky bit in i_mode, unless we want the VFS
193          * to check permissions.  This prevents failures due to the
194          * check in may_delete().
195          */
196         fi->orig_i_mode = inode->i_mode;
197         if (!fc->default_permissions)
198                 inode->i_mode &= ~S_ISVTX;
199
200         fi->orig_ino = attr->ino;
201 }
202
203 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
204                             u64 attr_valid, u64 attr_version)
205 {
206         struct fuse_conn *fc = get_fuse_conn(inode);
207         struct fuse_inode *fi = get_fuse_inode(inode);
208         bool is_wb = fc->writeback_cache;
209         loff_t oldsize;
210         struct timespec old_mtime;
211
212         spin_lock(&fc->lock);
213         if ((attr_version != 0 && fi->attr_version > attr_version) ||
214             test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) {
215                 spin_unlock(&fc->lock);
216                 return;
217         }
218
219         old_mtime = inode->i_mtime;
220         fuse_change_attributes_common(inode, attr, attr_valid);
221
222         oldsize = inode->i_size;
223         /*
224          * In case of writeback_cache enabled, the cached writes beyond EOF
225          * extend local i_size without keeping userspace server in sync. So,
226          * attr->size coming from server can be stale. We cannot trust it.
227          */
228         if (!is_wb || !S_ISREG(inode->i_mode))
229                 i_size_write(inode, attr->size);
230         spin_unlock(&fc->lock);
231
232         if (!is_wb && S_ISREG(inode->i_mode)) {
233                 bool inval = false;
234
235                 if (oldsize != attr->size) {
236                         truncate_pagecache(inode, attr->size);
237                         inval = true;
238                 } else if (fc->auto_inval_data) {
239                         struct timespec new_mtime = {
240                                 .tv_sec = attr->mtime,
241                                 .tv_nsec = attr->mtimensec,
242                         };
243
244                         /*
245                          * Auto inval mode also checks and invalidates if mtime
246                          * has changed.
247                          */
248                         if (!timespec_equal(&old_mtime, &new_mtime))
249                                 inval = true;
250                 }
251
252                 if (inval)
253                         invalidate_inode_pages2(inode->i_mapping);
254         }
255 }
256
257 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
258 {
259         inode->i_mode = attr->mode & S_IFMT;
260         inode->i_size = attr->size;
261         inode->i_mtime.tv_sec  = attr->mtime;
262         inode->i_mtime.tv_nsec = attr->mtimensec;
263         inode->i_ctime.tv_sec  = attr->ctime;
264         inode->i_ctime.tv_nsec = attr->ctimensec;
265         if (S_ISREG(inode->i_mode)) {
266                 fuse_init_common(inode);
267                 fuse_init_file_inode(inode);
268         } else if (S_ISDIR(inode->i_mode))
269                 fuse_init_dir(inode);
270         else if (S_ISLNK(inode->i_mode))
271                 fuse_init_symlink(inode);
272         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
273                  S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
274                 fuse_init_common(inode);
275                 init_special_inode(inode, inode->i_mode,
276                                    new_decode_dev(attr->rdev));
277         } else
278                 BUG();
279 }
280
281 int fuse_inode_eq(struct inode *inode, void *_nodeidp)
282 {
283         u64 nodeid = *(u64 *) _nodeidp;
284         if (get_node_id(inode) == nodeid)
285                 return 1;
286         else
287                 return 0;
288 }
289
290 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
291 {
292         u64 nodeid = *(u64 *) _nodeidp;
293         get_fuse_inode(inode)->nodeid = nodeid;
294         return 0;
295 }
296
297 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
298                         int generation, struct fuse_attr *attr,
299                         u64 attr_valid, u64 attr_version)
300 {
301         struct inode *inode;
302         struct fuse_inode *fi;
303         struct fuse_conn *fc = get_fuse_conn_super(sb);
304
305  retry:
306         inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
307         if (!inode)
308                 return NULL;
309
310         if ((inode->i_state & I_NEW)) {
311                 inode->i_flags |= S_NOATIME;
312                 if (!fc->writeback_cache || !S_ISREG(attr->mode))
313                         inode->i_flags |= S_NOCMTIME;
314                 inode->i_generation = generation;
315                 fuse_init_inode(inode, attr);
316                 unlock_new_inode(inode);
317         } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
318                 /* Inode has changed type, any I/O on the old should fail */
319                 make_bad_inode(inode);
320                 iput(inode);
321                 goto retry;
322         }
323
324         fi = get_fuse_inode(inode);
325         spin_lock(&fc->lock);
326         fi->nlookup++;
327         spin_unlock(&fc->lock);
328         fuse_change_attributes(inode, attr, attr_valid, attr_version);
329
330         return inode;
331 }
332
333 int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
334                              loff_t offset, loff_t len)
335 {
336         struct inode *inode;
337         pgoff_t pg_start;
338         pgoff_t pg_end;
339
340         inode = ilookup5(sb, nodeid, fuse_inode_eq, &nodeid);
341         if (!inode)
342                 return -ENOENT;
343
344         fuse_invalidate_attr(inode);
345         forget_all_cached_acls(inode);
346         if (offset >= 0) {
347                 pg_start = offset >> PAGE_SHIFT;
348                 if (len <= 0)
349                         pg_end = -1;
350                 else
351                         pg_end = (offset + len - 1) >> PAGE_SHIFT;
352                 invalidate_inode_pages2_range(inode->i_mapping,
353                                               pg_start, pg_end);
354         }
355         iput(inode);
356         return 0;
357 }
358
359 void fuse_lock_inode(struct inode *inode)
360 {
361         if (!get_fuse_conn(inode)->parallel_dirops)
362                 mutex_lock(&get_fuse_inode(inode)->mutex);
363 }
364
365 void fuse_unlock_inode(struct inode *inode)
366 {
367         if (!get_fuse_conn(inode)->parallel_dirops)
368                 mutex_unlock(&get_fuse_inode(inode)->mutex);
369 }
370
371 static void fuse_umount_begin(struct super_block *sb)
372 {
373         fuse_abort_conn(get_fuse_conn_super(sb));
374 }
375
376 static void fuse_send_destroy(struct fuse_conn *fc)
377 {
378         struct fuse_req *req = fc->destroy_req;
379         if (req && fc->conn_init) {
380                 fc->destroy_req = NULL;
381                 req->in.h.opcode = FUSE_DESTROY;
382                 __set_bit(FR_FORCE, &req->flags);
383                 __clear_bit(FR_BACKGROUND, &req->flags);
384                 fuse_request_send(fc, req);
385                 fuse_put_request(fc, req);
386         }
387 }
388
389 static void fuse_put_super(struct super_block *sb)
390 {
391         struct fuse_conn *fc = get_fuse_conn_super(sb);
392
393         fuse_send_destroy(fc);
394
395         fuse_abort_conn(fc);
396         mutex_lock(&fuse_mutex);
397         list_del(&fc->entry);
398         fuse_ctl_remove_conn(fc);
399         mutex_unlock(&fuse_mutex);
400
401         fuse_conn_put(fc);
402 }
403
404 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
405 {
406         stbuf->f_type    = FUSE_SUPER_MAGIC;
407         stbuf->f_bsize   = attr->bsize;
408         stbuf->f_frsize  = attr->frsize;
409         stbuf->f_blocks  = attr->blocks;
410         stbuf->f_bfree   = attr->bfree;
411         stbuf->f_bavail  = attr->bavail;
412         stbuf->f_files   = attr->files;
413         stbuf->f_ffree   = attr->ffree;
414         stbuf->f_namelen = attr->namelen;
415         /* fsid is left zero */
416 }
417
418 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
419 {
420         struct super_block *sb = dentry->d_sb;
421         struct fuse_conn *fc = get_fuse_conn_super(sb);
422         FUSE_ARGS(args);
423         struct fuse_statfs_out outarg;
424         int err;
425
426         if (!fuse_allow_current_process(fc)) {
427                 buf->f_type = FUSE_SUPER_MAGIC;
428                 return 0;
429         }
430
431         memset(&outarg, 0, sizeof(outarg));
432         args.in.numargs = 0;
433         args.in.h.opcode = FUSE_STATFS;
434         args.in.h.nodeid = get_node_id(d_inode(dentry));
435         args.out.numargs = 1;
436         args.out.args[0].size = sizeof(outarg);
437         args.out.args[0].value = &outarg;
438         err = fuse_simple_request(fc, &args);
439         if (!err)
440                 convert_fuse_statfs(buf, &outarg.st);
441         return err;
442 }
443
444 enum {
445         OPT_FD,
446         OPT_ROOTMODE,
447         OPT_USER_ID,
448         OPT_GROUP_ID,
449         OPT_DEFAULT_PERMISSIONS,
450         OPT_ALLOW_OTHER,
451         OPT_MAX_READ,
452         OPT_BLKSIZE,
453         OPT_ERR
454 };
455
456 static const match_table_t tokens = {
457         {OPT_FD,                        "fd=%u"},
458         {OPT_ROOTMODE,                  "rootmode=%o"},
459         {OPT_USER_ID,                   "user_id=%u"},
460         {OPT_GROUP_ID,                  "group_id=%u"},
461         {OPT_DEFAULT_PERMISSIONS,       "default_permissions"},
462         {OPT_ALLOW_OTHER,               "allow_other"},
463         {OPT_MAX_READ,                  "max_read=%u"},
464         {OPT_BLKSIZE,                   "blksize=%u"},
465         {OPT_ERR,                       NULL}
466 };
467
468 static int fuse_match_uint(substring_t *s, unsigned int *res)
469 {
470         int err = -ENOMEM;
471         char *buf = match_strdup(s);
472         if (buf) {
473                 err = kstrtouint(buf, 10, res);
474                 kfree(buf);
475         }
476         return err;
477 }
478
479 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
480 {
481         char *p;
482         memset(d, 0, sizeof(struct fuse_mount_data));
483         d->max_read = ~0;
484         d->blksize = FUSE_DEFAULT_BLKSIZE;
485
486         while ((p = strsep(&opt, ",")) != NULL) {
487                 int token;
488                 int value;
489                 unsigned uv;
490                 substring_t args[MAX_OPT_ARGS];
491                 if (!*p)
492                         continue;
493
494                 token = match_token(p, tokens, args);
495                 switch (token) {
496                 case OPT_FD:
497                         if (match_int(&args[0], &value))
498                                 return 0;
499                         d->fd = value;
500                         d->fd_present = 1;
501                         break;
502
503                 case OPT_ROOTMODE:
504                         if (match_octal(&args[0], &value))
505                                 return 0;
506                         if (!fuse_valid_type(value))
507                                 return 0;
508                         d->rootmode = value;
509                         d->rootmode_present = 1;
510                         break;
511
512                 case OPT_USER_ID:
513                         if (fuse_match_uint(&args[0], &uv))
514                                 return 0;
515                         d->user_id = make_kuid(current_user_ns(), uv);
516                         if (!uid_valid(d->user_id))
517                                 return 0;
518                         d->user_id_present = 1;
519                         break;
520
521                 case OPT_GROUP_ID:
522                         if (fuse_match_uint(&args[0], &uv))
523                                 return 0;
524                         d->group_id = make_kgid(current_user_ns(), uv);
525                         if (!gid_valid(d->group_id))
526                                 return 0;
527                         d->group_id_present = 1;
528                         break;
529
530                 case OPT_DEFAULT_PERMISSIONS:
531                         d->default_permissions = 1;
532                         break;
533
534                 case OPT_ALLOW_OTHER:
535                         d->allow_other = 1;
536                         break;
537
538                 case OPT_MAX_READ:
539                         if (match_int(&args[0], &value))
540                                 return 0;
541                         d->max_read = value;
542                         break;
543
544                 case OPT_BLKSIZE:
545                         if (!is_bdev || match_int(&args[0], &value))
546                                 return 0;
547                         d->blksize = value;
548                         break;
549
550                 default:
551                         return 0;
552                 }
553         }
554
555         if (!d->fd_present || !d->rootmode_present ||
556             !d->user_id_present || !d->group_id_present)
557                 return 0;
558
559         return 1;
560 }
561
562 static int fuse_show_options(struct seq_file *m, struct dentry *root)
563 {
564         struct super_block *sb = root->d_sb;
565         struct fuse_conn *fc = get_fuse_conn_super(sb);
566
567         seq_printf(m, ",user_id=%u", from_kuid_munged(&init_user_ns, fc->user_id));
568         seq_printf(m, ",group_id=%u", from_kgid_munged(&init_user_ns, fc->group_id));
569         if (fc->default_permissions)
570                 seq_puts(m, ",default_permissions");
571         if (fc->allow_other)
572                 seq_puts(m, ",allow_other");
573         if (fc->max_read != ~0)
574                 seq_printf(m, ",max_read=%u", fc->max_read);
575         if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
576                 seq_printf(m, ",blksize=%lu", sb->s_blocksize);
577         return 0;
578 }
579
580 static void fuse_iqueue_init(struct fuse_iqueue *fiq)
581 {
582         memset(fiq, 0, sizeof(struct fuse_iqueue));
583         init_waitqueue_head(&fiq->waitq);
584         INIT_LIST_HEAD(&fiq->pending);
585         INIT_LIST_HEAD(&fiq->interrupts);
586         fiq->forget_list_tail = &fiq->forget_list_head;
587         fiq->connected = 1;
588 }
589
590 static void fuse_pqueue_init(struct fuse_pqueue *fpq)
591 {
592         memset(fpq, 0, sizeof(struct fuse_pqueue));
593         spin_lock_init(&fpq->lock);
594         INIT_LIST_HEAD(&fpq->processing);
595         INIT_LIST_HEAD(&fpq->io);
596         fpq->connected = 1;
597 }
598
599 void fuse_conn_init(struct fuse_conn *fc)
600 {
601         memset(fc, 0, sizeof(*fc));
602         spin_lock_init(&fc->lock);
603         init_rwsem(&fc->killsb);
604         atomic_set(&fc->count, 1);
605         atomic_set(&fc->dev_count, 1);
606         init_waitqueue_head(&fc->blocked_waitq);
607         init_waitqueue_head(&fc->reserved_req_waitq);
608         fuse_iqueue_init(&fc->iq);
609         INIT_LIST_HEAD(&fc->bg_queue);
610         INIT_LIST_HEAD(&fc->entry);
611         INIT_LIST_HEAD(&fc->devices);
612         atomic_set(&fc->num_waiting, 0);
613         fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
614         fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
615         fc->khctr = 0;
616         fc->polled_files = RB_ROOT;
617         fc->blocked = 0;
618         fc->initialized = 0;
619         fc->connected = 1;
620         fc->attr_version = 1;
621         get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
622 }
623 EXPORT_SYMBOL_GPL(fuse_conn_init);
624
625 void fuse_conn_put(struct fuse_conn *fc)
626 {
627         if (atomic_dec_and_test(&fc->count)) {
628                 if (fc->destroy_req)
629                         fuse_request_free(fc->destroy_req);
630                 fc->release(fc);
631         }
632 }
633 EXPORT_SYMBOL_GPL(fuse_conn_put);
634
635 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
636 {
637         atomic_inc(&fc->count);
638         return fc;
639 }
640 EXPORT_SYMBOL_GPL(fuse_conn_get);
641
642 static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
643 {
644         struct fuse_attr attr;
645         memset(&attr, 0, sizeof(attr));
646
647         attr.mode = mode;
648         attr.ino = FUSE_ROOT_ID;
649         attr.nlink = 1;
650         return fuse_iget(sb, 1, 0, &attr, 0, 0);
651 }
652
653 struct fuse_inode_handle {
654         u64 nodeid;
655         u32 generation;
656 };
657
658 static struct dentry *fuse_get_dentry(struct super_block *sb,
659                                       struct fuse_inode_handle *handle)
660 {
661         struct fuse_conn *fc = get_fuse_conn_super(sb);
662         struct inode *inode;
663         struct dentry *entry;
664         int err = -ESTALE;
665
666         if (handle->nodeid == 0)
667                 goto out_err;
668
669         inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
670         if (!inode) {
671                 struct fuse_entry_out outarg;
672                 const struct qstr name = QSTR_INIT(".", 1);
673
674                 if (!fc->export_support)
675                         goto out_err;
676
677                 err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
678                                        &inode);
679                 if (err && err != -ENOENT)
680                         goto out_err;
681                 if (err || !inode) {
682                         err = -ESTALE;
683                         goto out_err;
684                 }
685                 err = -EIO;
686                 if (get_node_id(inode) != handle->nodeid)
687                         goto out_iput;
688         }
689         err = -ESTALE;
690         if (inode->i_generation != handle->generation)
691                 goto out_iput;
692
693         entry = d_obtain_alias(inode);
694         if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID)
695                 fuse_invalidate_entry_cache(entry);
696
697         return entry;
698
699  out_iput:
700         iput(inode);
701  out_err:
702         return ERR_PTR(err);
703 }
704
705 static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len,
706                            struct inode *parent)
707 {
708         int len = parent ? 6 : 3;
709         u64 nodeid;
710         u32 generation;
711
712         if (*max_len < len) {
713                 *max_len = len;
714                 return  FILEID_INVALID;
715         }
716
717         nodeid = get_fuse_inode(inode)->nodeid;
718         generation = inode->i_generation;
719
720         fh[0] = (u32)(nodeid >> 32);
721         fh[1] = (u32)(nodeid & 0xffffffff);
722         fh[2] = generation;
723
724         if (parent) {
725                 nodeid = get_fuse_inode(parent)->nodeid;
726                 generation = parent->i_generation;
727
728                 fh[3] = (u32)(nodeid >> 32);
729                 fh[4] = (u32)(nodeid & 0xffffffff);
730                 fh[5] = generation;
731         }
732
733         *max_len = len;
734         return parent ? 0x82 : 0x81;
735 }
736
737 static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
738                 struct fid *fid, int fh_len, int fh_type)
739 {
740         struct fuse_inode_handle handle;
741
742         if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
743                 return NULL;
744
745         handle.nodeid = (u64) fid->raw[0] << 32;
746         handle.nodeid |= (u64) fid->raw[1];
747         handle.generation = fid->raw[2];
748         return fuse_get_dentry(sb, &handle);
749 }
750
751 static struct dentry *fuse_fh_to_parent(struct super_block *sb,
752                 struct fid *fid, int fh_len, int fh_type)
753 {
754         struct fuse_inode_handle parent;
755
756         if (fh_type != 0x82 || fh_len < 6)
757                 return NULL;
758
759         parent.nodeid = (u64) fid->raw[3] << 32;
760         parent.nodeid |= (u64) fid->raw[4];
761         parent.generation = fid->raw[5];
762         return fuse_get_dentry(sb, &parent);
763 }
764
765 static struct dentry *fuse_get_parent(struct dentry *child)
766 {
767         struct inode *child_inode = d_inode(child);
768         struct fuse_conn *fc = get_fuse_conn(child_inode);
769         struct inode *inode;
770         struct dentry *parent;
771         struct fuse_entry_out outarg;
772         const struct qstr name = QSTR_INIT("..", 2);
773         int err;
774
775         if (!fc->export_support)
776                 return ERR_PTR(-ESTALE);
777
778         err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
779                                &name, &outarg, &inode);
780         if (err) {
781                 if (err == -ENOENT)
782                         return ERR_PTR(-ESTALE);
783                 return ERR_PTR(err);
784         }
785
786         parent = d_obtain_alias(inode);
787         if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID)
788                 fuse_invalidate_entry_cache(parent);
789
790         return parent;
791 }
792
793 static const struct export_operations fuse_export_operations = {
794         .fh_to_dentry   = fuse_fh_to_dentry,
795         .fh_to_parent   = fuse_fh_to_parent,
796         .encode_fh      = fuse_encode_fh,
797         .get_parent     = fuse_get_parent,
798 };
799
800 static const struct super_operations fuse_super_operations = {
801         .alloc_inode    = fuse_alloc_inode,
802         .destroy_inode  = fuse_destroy_inode,
803         .evict_inode    = fuse_evict_inode,
804         .write_inode    = fuse_write_inode,
805         .drop_inode     = generic_delete_inode,
806         .remount_fs     = fuse_remount_fs,
807         .put_super      = fuse_put_super,
808         .umount_begin   = fuse_umount_begin,
809         .statfs         = fuse_statfs,
810         .show_options   = fuse_show_options,
811 };
812
813 static void sanitize_global_limit(unsigned *limit)
814 {
815         if (*limit == 0)
816                 *limit = ((totalram_pages << PAGE_SHIFT) >> 13) /
817                          sizeof(struct fuse_req);
818
819         if (*limit >= 1 << 16)
820                 *limit = (1 << 16) - 1;
821 }
822
823 static int set_global_limit(const char *val, struct kernel_param *kp)
824 {
825         int rv;
826
827         rv = param_set_uint(val, kp);
828         if (rv)
829                 return rv;
830
831         sanitize_global_limit((unsigned *)kp->arg);
832
833         return 0;
834 }
835
836 static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg)
837 {
838         int cap_sys_admin = capable(CAP_SYS_ADMIN);
839
840         if (arg->minor < 13)
841                 return;
842
843         sanitize_global_limit(&max_user_bgreq);
844         sanitize_global_limit(&max_user_congthresh);
845
846         if (arg->max_background) {
847                 fc->max_background = arg->max_background;
848
849                 if (!cap_sys_admin && fc->max_background > max_user_bgreq)
850                         fc->max_background = max_user_bgreq;
851         }
852         if (arg->congestion_threshold) {
853                 fc->congestion_threshold = arg->congestion_threshold;
854
855                 if (!cap_sys_admin &&
856                     fc->congestion_threshold > max_user_congthresh)
857                         fc->congestion_threshold = max_user_congthresh;
858         }
859 }
860
861 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
862 {
863         struct fuse_init_out *arg = &req->misc.init_out;
864
865         if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
866                 fc->conn_error = 1;
867         else {
868                 unsigned long ra_pages;
869
870                 process_init_limits(fc, arg);
871
872                 if (arg->minor >= 6) {
873                         ra_pages = arg->max_readahead / PAGE_SIZE;
874                         if (arg->flags & FUSE_ASYNC_READ)
875                                 fc->async_read = 1;
876                         if (!(arg->flags & FUSE_POSIX_LOCKS))
877                                 fc->no_lock = 1;
878                         if (arg->minor >= 17) {
879                                 if (!(arg->flags & FUSE_FLOCK_LOCKS))
880                                         fc->no_flock = 1;
881                         } else {
882                                 if (!(arg->flags & FUSE_POSIX_LOCKS))
883                                         fc->no_flock = 1;
884                         }
885                         if (arg->flags & FUSE_ATOMIC_O_TRUNC)
886                                 fc->atomic_o_trunc = 1;
887                         if (arg->minor >= 9) {
888                                 /* LOOKUP has dependency on proto version */
889                                 if (arg->flags & FUSE_EXPORT_SUPPORT)
890                                         fc->export_support = 1;
891                         }
892                         if (arg->flags & FUSE_BIG_WRITES)
893                                 fc->big_writes = 1;
894                         if (arg->flags & FUSE_DONT_MASK)
895                                 fc->dont_mask = 1;
896                         if (arg->flags & FUSE_AUTO_INVAL_DATA)
897                                 fc->auto_inval_data = 1;
898                         if (arg->flags & FUSE_DO_READDIRPLUS) {
899                                 fc->do_readdirplus = 1;
900                                 if (arg->flags & FUSE_READDIRPLUS_AUTO)
901                                         fc->readdirplus_auto = 1;
902                         }
903                         if (arg->flags & FUSE_ASYNC_DIO)
904                                 fc->async_dio = 1;
905                         if (arg->flags & FUSE_WRITEBACK_CACHE)
906                                 fc->writeback_cache = 1;
907                         if (arg->flags & FUSE_PARALLEL_DIROPS)
908                                 fc->parallel_dirops = 1;
909                         if (arg->flags & FUSE_HANDLE_KILLPRIV)
910                                 fc->handle_killpriv = 1;
911                         if (arg->time_gran && arg->time_gran <= 1000000000)
912                                 fc->sb->s_time_gran = arg->time_gran;
913                         if ((arg->flags & FUSE_POSIX_ACL)) {
914                                 fc->default_permissions = 1;
915                                 fc->posix_acl = 1;
916                                 fc->sb->s_xattr = fuse_acl_xattr_handlers;
917                         }
918                 } else {
919                         ra_pages = fc->max_read / PAGE_SIZE;
920                         fc->no_lock = 1;
921                         fc->no_flock = 1;
922                 }
923
924                 fc->sb->s_bdi->ra_pages =
925                                 min(fc->sb->s_bdi->ra_pages, ra_pages);
926                 fc->minor = arg->minor;
927                 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
928                 fc->max_write = max_t(unsigned, 4096, fc->max_write);
929                 fc->conn_init = 1;
930         }
931         fuse_set_initialized(fc);
932         wake_up_all(&fc->blocked_waitq);
933 }
934
935 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
936 {
937         struct fuse_init_in *arg = &req->misc.init_in;
938
939         arg->major = FUSE_KERNEL_VERSION;
940         arg->minor = FUSE_KERNEL_MINOR_VERSION;
941         arg->max_readahead = fc->sb->s_bdi->ra_pages * PAGE_SIZE;
942         arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
943                 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
944                 FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
945                 FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
946                 FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
947                 FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT |
948                 FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL;
949         req->in.h.opcode = FUSE_INIT;
950         req->in.numargs = 1;
951         req->in.args[0].size = sizeof(*arg);
952         req->in.args[0].value = arg;
953         req->out.numargs = 1;
954         /* Variable length argument used for backward compatibility
955            with interface version < 7.5.  Rest of init_out is zeroed
956            by do_get_request(), so a short reply is not a problem */
957         req->out.argvar = 1;
958         req->out.args[0].size = sizeof(struct fuse_init_out);
959         req->out.args[0].value = &req->misc.init_out;
960         req->end = process_init_reply;
961         fuse_request_send_background(fc, req);
962 }
963
964 static void fuse_free_conn(struct fuse_conn *fc)
965 {
966         WARN_ON(!list_empty(&fc->devices));
967         kfree_rcu(fc, rcu);
968 }
969
970 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
971 {
972         int err;
973         char *suffix = "";
974
975         if (sb->s_bdev)
976                 suffix = "-fuseblk";
977         err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev),
978                                    MINOR(fc->dev), suffix);
979         if (err)
980                 return err;
981
982         sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_SIZE;
983         /* fuse does it's own writeback accounting */
984         sb->s_bdi->capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;
985
986         /*
987          * For a single fuse filesystem use max 1% of dirty +
988          * writeback threshold.
989          *
990          * This gives about 1M of write buffer for memory maps on a
991          * machine with 1G and 10% dirty_ratio, which should be more
992          * than enough.
993          *
994          * Privileged users can raise it by writing to
995          *
996          *    /sys/class/bdi/<bdi>/max_ratio
997          */
998         bdi_set_max_ratio(sb->s_bdi, 1);
999
1000         return 0;
1001 }
1002
1003 struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc)
1004 {
1005         struct fuse_dev *fud;
1006
1007         fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL);
1008         if (fud) {
1009                 fud->fc = fuse_conn_get(fc);
1010                 fuse_pqueue_init(&fud->pq);
1011
1012                 spin_lock(&fc->lock);
1013                 list_add_tail(&fud->entry, &fc->devices);
1014                 spin_unlock(&fc->lock);
1015         }
1016
1017         return fud;
1018 }
1019 EXPORT_SYMBOL_GPL(fuse_dev_alloc);
1020
1021 void fuse_dev_free(struct fuse_dev *fud)
1022 {
1023         struct fuse_conn *fc = fud->fc;
1024
1025         if (fc) {
1026                 spin_lock(&fc->lock);
1027                 list_del(&fud->entry);
1028                 spin_unlock(&fc->lock);
1029
1030                 fuse_conn_put(fc);
1031         }
1032         kfree(fud);
1033 }
1034 EXPORT_SYMBOL_GPL(fuse_dev_free);
1035
1036 static int fuse_fill_super(struct super_block *sb, void *data, int silent)
1037 {
1038         struct fuse_dev *fud;
1039         struct fuse_conn *fc;
1040         struct inode *root;
1041         struct fuse_mount_data d;
1042         struct file *file;
1043         struct dentry *root_dentry;
1044         struct fuse_req *init_req;
1045         int err;
1046         int is_bdev = sb->s_bdev != NULL;
1047
1048         err = -EINVAL;
1049         if (sb->s_flags & MS_MANDLOCK)
1050                 goto err;
1051
1052         sb->s_flags &= ~(MS_NOSEC | MS_I_VERSION);
1053
1054         if (!parse_fuse_opt(data, &d, is_bdev))
1055                 goto err;
1056
1057         if (is_bdev) {
1058 #ifdef CONFIG_BLOCK
1059                 err = -EINVAL;
1060                 if (!sb_set_blocksize(sb, d.blksize))
1061                         goto err;
1062 #endif
1063         } else {
1064                 sb->s_blocksize = PAGE_SIZE;
1065                 sb->s_blocksize_bits = PAGE_SHIFT;
1066         }
1067         sb->s_magic = FUSE_SUPER_MAGIC;
1068         sb->s_op = &fuse_super_operations;
1069         sb->s_xattr = fuse_xattr_handlers;
1070         sb->s_maxbytes = MAX_LFS_FILESIZE;
1071         sb->s_time_gran = 1;
1072         sb->s_export_op = &fuse_export_operations;
1073
1074         file = fget(d.fd);
1075         err = -EINVAL;
1076         if (!file)
1077                 goto err;
1078
1079         if ((file->f_op != &fuse_dev_operations) ||
1080             (file->f_cred->user_ns != &init_user_ns))
1081                 goto err_fput;
1082
1083         fc = kmalloc(sizeof(*fc), GFP_KERNEL);
1084         err = -ENOMEM;
1085         if (!fc)
1086                 goto err_fput;
1087
1088         fuse_conn_init(fc);
1089         fc->release = fuse_free_conn;
1090
1091         fud = fuse_dev_alloc(fc);
1092         if (!fud)
1093                 goto err_put_conn;
1094
1095         fc->dev = sb->s_dev;
1096         fc->sb = sb;
1097         err = fuse_bdi_init(fc, sb);
1098         if (err)
1099                 goto err_dev_free;
1100
1101         /* Handle umasking inside the fuse code */
1102         if (sb->s_flags & MS_POSIXACL)
1103                 fc->dont_mask = 1;
1104         sb->s_flags |= MS_POSIXACL;
1105
1106         fc->default_permissions = d.default_permissions;
1107         fc->allow_other = d.allow_other;
1108         fc->user_id = d.user_id;
1109         fc->group_id = d.group_id;
1110         fc->max_read = max_t(unsigned, 4096, d.max_read);
1111
1112         /* Used by get_root_inode() */
1113         sb->s_fs_info = fc;
1114
1115         err = -ENOMEM;
1116         root = fuse_get_root_inode(sb, d.rootmode);
1117         sb->s_d_op = &fuse_root_dentry_operations;
1118         root_dentry = d_make_root(root);
1119         if (!root_dentry)
1120                 goto err_dev_free;
1121         /* Root dentry doesn't have .d_revalidate */
1122         sb->s_d_op = &fuse_dentry_operations;
1123
1124         init_req = fuse_request_alloc(0);
1125         if (!init_req)
1126                 goto err_put_root;
1127         __set_bit(FR_BACKGROUND, &init_req->flags);
1128
1129         if (is_bdev) {
1130                 fc->destroy_req = fuse_request_alloc(0);
1131                 if (!fc->destroy_req)
1132                         goto err_free_init_req;
1133         }
1134
1135         mutex_lock(&fuse_mutex);
1136         err = -EINVAL;
1137         if (file->private_data)
1138                 goto err_unlock;
1139
1140         err = fuse_ctl_add_conn(fc);
1141         if (err)
1142                 goto err_unlock;
1143
1144         list_add_tail(&fc->entry, &fuse_conn_list);
1145         sb->s_root = root_dentry;
1146         file->private_data = fud;
1147         mutex_unlock(&fuse_mutex);
1148         /*
1149          * atomic_dec_and_test() in fput() provides the necessary
1150          * memory barrier for file->private_data to be visible on all
1151          * CPUs after this
1152          */
1153         fput(file);
1154
1155         fuse_send_init(fc, init_req);
1156
1157         return 0;
1158
1159  err_unlock:
1160         mutex_unlock(&fuse_mutex);
1161  err_free_init_req:
1162         fuse_request_free(init_req);
1163  err_put_root:
1164         dput(root_dentry);
1165  err_dev_free:
1166         fuse_dev_free(fud);
1167  err_put_conn:
1168         fuse_conn_put(fc);
1169  err_fput:
1170         fput(file);
1171  err:
1172         return err;
1173 }
1174
1175 static struct dentry *fuse_mount(struct file_system_type *fs_type,
1176                        int flags, const char *dev_name,
1177                        void *raw_data)
1178 {
1179         return mount_nodev(fs_type, flags, raw_data, fuse_fill_super);
1180 }
1181
1182 static void fuse_kill_sb_anon(struct super_block *sb)
1183 {
1184         struct fuse_conn *fc = get_fuse_conn_super(sb);
1185
1186         if (fc) {
1187                 down_write(&fc->killsb);
1188                 fc->sb = NULL;
1189                 up_write(&fc->killsb);
1190         }
1191
1192         kill_anon_super(sb);
1193 }
1194
1195 static struct file_system_type fuse_fs_type = {
1196         .owner          = THIS_MODULE,
1197         .name           = "fuse",
1198         .fs_flags       = FS_HAS_SUBTYPE,
1199         .mount          = fuse_mount,
1200         .kill_sb        = fuse_kill_sb_anon,
1201 };
1202 MODULE_ALIAS_FS("fuse");
1203
1204 #ifdef CONFIG_BLOCK
1205 static struct dentry *fuse_mount_blk(struct file_system_type *fs_type,
1206                            int flags, const char *dev_name,
1207                            void *raw_data)
1208 {
1209         return mount_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super);
1210 }
1211
1212 static void fuse_kill_sb_blk(struct super_block *sb)
1213 {
1214         struct fuse_conn *fc = get_fuse_conn_super(sb);
1215
1216         if (fc) {
1217                 down_write(&fc->killsb);
1218                 fc->sb = NULL;
1219                 up_write(&fc->killsb);
1220         }
1221
1222         kill_block_super(sb);
1223 }
1224
1225 static struct file_system_type fuseblk_fs_type = {
1226         .owner          = THIS_MODULE,
1227         .name           = "fuseblk",
1228         .mount          = fuse_mount_blk,
1229         .kill_sb        = fuse_kill_sb_blk,
1230         .fs_flags       = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
1231 };
1232 MODULE_ALIAS_FS("fuseblk");
1233
1234 static inline int register_fuseblk(void)
1235 {
1236         return register_filesystem(&fuseblk_fs_type);
1237 }
1238
1239 static inline void unregister_fuseblk(void)
1240 {
1241         unregister_filesystem(&fuseblk_fs_type);
1242 }
1243 #else
1244 static inline int register_fuseblk(void)
1245 {
1246         return 0;
1247 }
1248
1249 static inline void unregister_fuseblk(void)
1250 {
1251 }
1252 #endif
1253
1254 static void fuse_inode_init_once(void *foo)
1255 {
1256         struct inode *inode = foo;
1257
1258         inode_init_once(inode);
1259 }
1260
1261 static int __init fuse_fs_init(void)
1262 {
1263         int err;
1264
1265         fuse_inode_cachep = kmem_cache_create("fuse_inode",
1266                                               sizeof(struct fuse_inode), 0,
1267                                               SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT,
1268                                               fuse_inode_init_once);
1269         err = -ENOMEM;
1270         if (!fuse_inode_cachep)
1271                 goto out;
1272
1273         err = register_fuseblk();
1274         if (err)
1275                 goto out2;
1276
1277         err = register_filesystem(&fuse_fs_type);
1278         if (err)
1279                 goto out3;
1280
1281         return 0;
1282
1283  out3:
1284         unregister_fuseblk();
1285  out2:
1286         kmem_cache_destroy(fuse_inode_cachep);
1287  out:
1288         return err;
1289 }
1290
1291 static void fuse_fs_cleanup(void)
1292 {
1293         unregister_filesystem(&fuse_fs_type);
1294         unregister_fuseblk();
1295
1296         /*
1297          * Make sure all delayed rcu free inodes are flushed before we
1298          * destroy cache.
1299          */
1300         rcu_barrier();
1301         kmem_cache_destroy(fuse_inode_cachep);
1302 }
1303
1304 static struct kobject *fuse_kobj;
1305
1306 static int fuse_sysfs_init(void)
1307 {
1308         int err;
1309
1310         fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
1311         if (!fuse_kobj) {
1312                 err = -ENOMEM;
1313                 goto out_err;
1314         }
1315
1316         err = sysfs_create_mount_point(fuse_kobj, "connections");
1317         if (err)
1318                 goto out_fuse_unregister;
1319
1320         return 0;
1321
1322  out_fuse_unregister:
1323         kobject_put(fuse_kobj);
1324  out_err:
1325         return err;
1326 }
1327
1328 static void fuse_sysfs_cleanup(void)
1329 {
1330         sysfs_remove_mount_point(fuse_kobj, "connections");
1331         kobject_put(fuse_kobj);
1332 }
1333
1334 static int __init fuse_init(void)
1335 {
1336         int res;
1337
1338         printk(KERN_INFO "fuse init (API version %i.%i)\n",
1339                FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
1340
1341         INIT_LIST_HEAD(&fuse_conn_list);
1342         res = fuse_fs_init();
1343         if (res)
1344                 goto err;
1345
1346         res = fuse_dev_init();
1347         if (res)
1348                 goto err_fs_cleanup;
1349
1350         res = fuse_sysfs_init();
1351         if (res)
1352                 goto err_dev_cleanup;
1353
1354         res = fuse_ctl_init();
1355         if (res)
1356                 goto err_sysfs_cleanup;
1357
1358         sanitize_global_limit(&max_user_bgreq);
1359         sanitize_global_limit(&max_user_congthresh);
1360
1361         return 0;
1362
1363  err_sysfs_cleanup:
1364         fuse_sysfs_cleanup();
1365  err_dev_cleanup:
1366         fuse_dev_cleanup();
1367  err_fs_cleanup:
1368         fuse_fs_cleanup();
1369  err:
1370         return res;
1371 }
1372
1373 static void __exit fuse_exit(void)
1374 {
1375         printk(KERN_DEBUG "fuse exit\n");
1376
1377         fuse_ctl_cleanup();
1378         fuse_sysfs_cleanup();
1379         fuse_fs_cleanup();
1380         fuse_dev_cleanup();
1381 }
1382
1383 module_init(fuse_init);
1384 module_exit(fuse_exit);