[PATCH] restore sane ->umount_begin() API
[linux-2.6.git] / fs / fuse / inode.c
1 /*
2   FUSE: Filesystem in Userspace
3   Copyright (C) 2001-2006  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/parser.h>
18 #include <linux/statfs.h>
19 #include <linux/random.h>
20 #include <linux/sched.h>
21
22 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
23 MODULE_DESCRIPTION("Filesystem in Userspace");
24 MODULE_LICENSE("GPL");
25
26 static struct kmem_cache *fuse_inode_cachep;
27 struct list_head fuse_conn_list;
28 DEFINE_MUTEX(fuse_mutex);
29
30 #define FUSE_SUPER_MAGIC 0x65735546
31
32 #define FUSE_DEFAULT_BLKSIZE 512
33
34 struct fuse_mount_data {
35         int fd;
36         unsigned rootmode;
37         unsigned user_id;
38         unsigned group_id;
39         unsigned fd_present : 1;
40         unsigned rootmode_present : 1;
41         unsigned user_id_present : 1;
42         unsigned group_id_present : 1;
43         unsigned flags;
44         unsigned max_read;
45         unsigned blksize;
46 };
47
48 static struct inode *fuse_alloc_inode(struct super_block *sb)
49 {
50         struct inode *inode;
51         struct fuse_inode *fi;
52
53         inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
54         if (!inode)
55                 return NULL;
56
57         fi = get_fuse_inode(inode);
58         fi->i_time = 0;
59         fi->nodeid = 0;
60         fi->nlookup = 0;
61         fi->attr_version = 0;
62         INIT_LIST_HEAD(&fi->write_files);
63         fi->forget_req = fuse_request_alloc();
64         if (!fi->forget_req) {
65                 kmem_cache_free(fuse_inode_cachep, inode);
66                 return NULL;
67         }
68
69         return inode;
70 }
71
72 static void fuse_destroy_inode(struct inode *inode)
73 {
74         struct fuse_inode *fi = get_fuse_inode(inode);
75         BUG_ON(!list_empty(&fi->write_files));
76         if (fi->forget_req)
77                 fuse_request_free(fi->forget_req);
78         kmem_cache_free(fuse_inode_cachep, inode);
79 }
80
81 void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
82                       unsigned long nodeid, u64 nlookup)
83 {
84         struct fuse_forget_in *inarg = &req->misc.forget_in;
85         inarg->nlookup = nlookup;
86         req->in.h.opcode = FUSE_FORGET;
87         req->in.h.nodeid = nodeid;
88         req->in.numargs = 1;
89         req->in.args[0].size = sizeof(struct fuse_forget_in);
90         req->in.args[0].value = inarg;
91         request_send_noreply(fc, req);
92 }
93
94 static void fuse_clear_inode(struct inode *inode)
95 {
96         if (inode->i_sb->s_flags & MS_ACTIVE) {
97                 struct fuse_conn *fc = get_fuse_conn(inode);
98                 struct fuse_inode *fi = get_fuse_inode(inode);
99                 fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
100                 fi->forget_req = NULL;
101         }
102 }
103
104 static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
105 {
106         if (*flags & MS_MANDLOCK)
107                 return -EINVAL;
108
109         return 0;
110 }
111
112 static void fuse_truncate(struct address_space *mapping, loff_t offset)
113 {
114         /* See vmtruncate() */
115         unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
116         truncate_inode_pages(mapping, offset);
117         unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
118 }
119
120
121 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
122                             u64 attr_valid, u64 attr_version)
123 {
124         struct fuse_conn *fc = get_fuse_conn(inode);
125         struct fuse_inode *fi = get_fuse_inode(inode);
126         loff_t oldsize;
127
128         spin_lock(&fc->lock);
129         if (attr_version != 0 && fi->attr_version > attr_version) {
130                 spin_unlock(&fc->lock);
131                 return;
132         }
133         fi->attr_version = ++fc->attr_version;
134         fi->i_time = attr_valid;
135
136         inode->i_ino     = attr->ino;
137         inode->i_mode    = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
138         inode->i_nlink   = attr->nlink;
139         inode->i_uid     = attr->uid;
140         inode->i_gid     = attr->gid;
141         inode->i_blocks  = attr->blocks;
142         inode->i_atime.tv_sec   = attr->atime;
143         inode->i_atime.tv_nsec  = attr->atimensec;
144         inode->i_mtime.tv_sec   = attr->mtime;
145         inode->i_mtime.tv_nsec  = attr->mtimensec;
146         inode->i_ctime.tv_sec   = attr->ctime;
147         inode->i_ctime.tv_nsec  = attr->ctimensec;
148
149         if (attr->blksize != 0)
150                 inode->i_blkbits = ilog2(attr->blksize);
151         else
152                 inode->i_blkbits = inode->i_sb->s_blocksize_bits;
153
154         /*
155          * Don't set the sticky bit in i_mode, unless we want the VFS
156          * to check permissions.  This prevents failures due to the
157          * check in may_delete().
158          */
159         fi->orig_i_mode = inode->i_mode;
160         if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
161                 inode->i_mode &= ~S_ISVTX;
162
163         oldsize = inode->i_size;
164         i_size_write(inode, attr->size);
165         spin_unlock(&fc->lock);
166
167         if (S_ISREG(inode->i_mode) && oldsize != attr->size) {
168                 if (attr->size < oldsize)
169                         fuse_truncate(inode->i_mapping, attr->size);
170                 invalidate_inode_pages2(inode->i_mapping);
171         }
172 }
173
174 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
175 {
176         inode->i_mode = attr->mode & S_IFMT;
177         inode->i_size = attr->size;
178         if (S_ISREG(inode->i_mode)) {
179                 fuse_init_common(inode);
180                 fuse_init_file_inode(inode);
181         } else if (S_ISDIR(inode->i_mode))
182                 fuse_init_dir(inode);
183         else if (S_ISLNK(inode->i_mode))
184                 fuse_init_symlink(inode);
185         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
186                  S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
187                 fuse_init_common(inode);
188                 init_special_inode(inode, inode->i_mode,
189                                    new_decode_dev(attr->rdev));
190         } else
191                 BUG();
192 }
193
194 static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
195 {
196         unsigned long nodeid = *(unsigned long *) _nodeidp;
197         if (get_node_id(inode) == nodeid)
198                 return 1;
199         else
200                 return 0;
201 }
202
203 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
204 {
205         unsigned long nodeid = *(unsigned long *) _nodeidp;
206         get_fuse_inode(inode)->nodeid = nodeid;
207         return 0;
208 }
209
210 struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
211                         int generation, struct fuse_attr *attr,
212                         u64 attr_valid, u64 attr_version)
213 {
214         struct inode *inode;
215         struct fuse_inode *fi;
216         struct fuse_conn *fc = get_fuse_conn_super(sb);
217
218  retry:
219         inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
220         if (!inode)
221                 return NULL;
222
223         if ((inode->i_state & I_NEW)) {
224                 inode->i_flags |= S_NOATIME|S_NOCMTIME;
225                 inode->i_generation = generation;
226                 inode->i_data.backing_dev_info = &fc->bdi;
227                 fuse_init_inode(inode, attr);
228                 unlock_new_inode(inode);
229         } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
230                 /* Inode has changed type, any I/O on the old should fail */
231                 make_bad_inode(inode);
232                 iput(inode);
233                 goto retry;
234         }
235
236         fi = get_fuse_inode(inode);
237         spin_lock(&fc->lock);
238         fi->nlookup ++;
239         spin_unlock(&fc->lock);
240         fuse_change_attributes(inode, attr, attr_valid, attr_version);
241
242         return inode;
243 }
244
245 static void fuse_umount_begin(struct super_block *sb)
246 {
247         fuse_abort_conn(get_fuse_conn_super(sb));
248 }
249
250 static void fuse_send_destroy(struct fuse_conn *fc)
251 {
252         struct fuse_req *req = fc->destroy_req;
253         if (req && fc->conn_init) {
254                 fc->destroy_req = NULL;
255                 req->in.h.opcode = FUSE_DESTROY;
256                 req->force = 1;
257                 request_send(fc, req);
258                 fuse_put_request(fc, req);
259         }
260 }
261
262 static void fuse_put_super(struct super_block *sb)
263 {
264         struct fuse_conn *fc = get_fuse_conn_super(sb);
265
266         fuse_send_destroy(fc);
267         spin_lock(&fc->lock);
268         fc->connected = 0;
269         fc->blocked = 0;
270         spin_unlock(&fc->lock);
271         /* Flush all readers on this fs */
272         kill_fasync(&fc->fasync, SIGIO, POLL_IN);
273         wake_up_all(&fc->waitq);
274         wake_up_all(&fc->blocked_waitq);
275         wake_up_all(&fc->reserved_req_waitq);
276         mutex_lock(&fuse_mutex);
277         list_del(&fc->entry);
278         fuse_ctl_remove_conn(fc);
279         mutex_unlock(&fuse_mutex);
280         fuse_conn_put(fc);
281 }
282
283 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
284 {
285         stbuf->f_type    = FUSE_SUPER_MAGIC;
286         stbuf->f_bsize   = attr->bsize;
287         stbuf->f_frsize  = attr->frsize;
288         stbuf->f_blocks  = attr->blocks;
289         stbuf->f_bfree   = attr->bfree;
290         stbuf->f_bavail  = attr->bavail;
291         stbuf->f_files   = attr->files;
292         stbuf->f_ffree   = attr->ffree;
293         stbuf->f_namelen = attr->namelen;
294         /* fsid is left zero */
295 }
296
297 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
298 {
299         struct super_block *sb = dentry->d_sb;
300         struct fuse_conn *fc = get_fuse_conn_super(sb);
301         struct fuse_req *req;
302         struct fuse_statfs_out outarg;
303         int err;
304
305         if (!fuse_allow_task(fc, current)) {
306                 buf->f_type = FUSE_SUPER_MAGIC;
307                 return 0;
308         }
309
310         req = fuse_get_req(fc);
311         if (IS_ERR(req))
312                 return PTR_ERR(req);
313
314         memset(&outarg, 0, sizeof(outarg));
315         req->in.numargs = 0;
316         req->in.h.opcode = FUSE_STATFS;
317         req->in.h.nodeid = get_node_id(dentry->d_inode);
318         req->out.numargs = 1;
319         req->out.args[0].size =
320                 fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
321         req->out.args[0].value = &outarg;
322         request_send(fc, req);
323         err = req->out.h.error;
324         if (!err)
325                 convert_fuse_statfs(buf, &outarg.st);
326         fuse_put_request(fc, req);
327         return err;
328 }
329
330 enum {
331         OPT_FD,
332         OPT_ROOTMODE,
333         OPT_USER_ID,
334         OPT_GROUP_ID,
335         OPT_DEFAULT_PERMISSIONS,
336         OPT_ALLOW_OTHER,
337         OPT_MAX_READ,
338         OPT_BLKSIZE,
339         OPT_ERR
340 };
341
342 static match_table_t tokens = {
343         {OPT_FD,                        "fd=%u"},
344         {OPT_ROOTMODE,                  "rootmode=%o"},
345         {OPT_USER_ID,                   "user_id=%u"},
346         {OPT_GROUP_ID,                  "group_id=%u"},
347         {OPT_DEFAULT_PERMISSIONS,       "default_permissions"},
348         {OPT_ALLOW_OTHER,               "allow_other"},
349         {OPT_MAX_READ,                  "max_read=%u"},
350         {OPT_BLKSIZE,                   "blksize=%u"},
351         {OPT_ERR,                       NULL}
352 };
353
354 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
355 {
356         char *p;
357         memset(d, 0, sizeof(struct fuse_mount_data));
358         d->max_read = ~0;
359         d->blksize = FUSE_DEFAULT_BLKSIZE;
360
361         while ((p = strsep(&opt, ",")) != NULL) {
362                 int token;
363                 int value;
364                 substring_t args[MAX_OPT_ARGS];
365                 if (!*p)
366                         continue;
367
368                 token = match_token(p, tokens, args);
369                 switch (token) {
370                 case OPT_FD:
371                         if (match_int(&args[0], &value))
372                                 return 0;
373                         d->fd = value;
374                         d->fd_present = 1;
375                         break;
376
377                 case OPT_ROOTMODE:
378                         if (match_octal(&args[0], &value))
379                                 return 0;
380                         if (!fuse_valid_type(value))
381                                 return 0;
382                         d->rootmode = value;
383                         d->rootmode_present = 1;
384                         break;
385
386                 case OPT_USER_ID:
387                         if (match_int(&args[0], &value))
388                                 return 0;
389                         d->user_id = value;
390                         d->user_id_present = 1;
391                         break;
392
393                 case OPT_GROUP_ID:
394                         if (match_int(&args[0], &value))
395                                 return 0;
396                         d->group_id = value;
397                         d->group_id_present = 1;
398                         break;
399
400                 case OPT_DEFAULT_PERMISSIONS:
401                         d->flags |= FUSE_DEFAULT_PERMISSIONS;
402                         break;
403
404                 case OPT_ALLOW_OTHER:
405                         d->flags |= FUSE_ALLOW_OTHER;
406                         break;
407
408                 case OPT_MAX_READ:
409                         if (match_int(&args[0], &value))
410                                 return 0;
411                         d->max_read = value;
412                         break;
413
414                 case OPT_BLKSIZE:
415                         if (!is_bdev || match_int(&args[0], &value))
416                                 return 0;
417                         d->blksize = value;
418                         break;
419
420                 default:
421                         return 0;
422                 }
423         }
424
425         if (!d->fd_present || !d->rootmode_present ||
426             !d->user_id_present || !d->group_id_present)
427                 return 0;
428
429         return 1;
430 }
431
432 static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
433 {
434         struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
435
436         seq_printf(m, ",user_id=%u", fc->user_id);
437         seq_printf(m, ",group_id=%u", fc->group_id);
438         if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
439                 seq_puts(m, ",default_permissions");
440         if (fc->flags & FUSE_ALLOW_OTHER)
441                 seq_puts(m, ",allow_other");
442         if (fc->max_read != ~0)
443                 seq_printf(m, ",max_read=%u", fc->max_read);
444         if (mnt->mnt_sb->s_bdev &&
445             mnt->mnt_sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
446                 seq_printf(m, ",blksize=%lu", mnt->mnt_sb->s_blocksize);
447         return 0;
448 }
449
450 static struct fuse_conn *new_conn(void)
451 {
452         struct fuse_conn *fc;
453         int err;
454
455         fc = kzalloc(sizeof(*fc), GFP_KERNEL);
456         if (fc) {
457                 spin_lock_init(&fc->lock);
458                 mutex_init(&fc->inst_mutex);
459                 atomic_set(&fc->count, 1);
460                 init_waitqueue_head(&fc->waitq);
461                 init_waitqueue_head(&fc->blocked_waitq);
462                 init_waitqueue_head(&fc->reserved_req_waitq);
463                 INIT_LIST_HEAD(&fc->pending);
464                 INIT_LIST_HEAD(&fc->processing);
465                 INIT_LIST_HEAD(&fc->io);
466                 INIT_LIST_HEAD(&fc->interrupts);
467                 INIT_LIST_HEAD(&fc->bg_queue);
468                 atomic_set(&fc->num_waiting, 0);
469                 fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
470                 fc->bdi.unplug_io_fn = default_unplug_io_fn;
471                 err = bdi_init(&fc->bdi);
472                 if (err) {
473                         kfree(fc);
474                         fc = NULL;
475                         goto out;
476                 }
477                 fc->reqctr = 0;
478                 fc->blocked = 1;
479                 fc->attr_version = 1;
480                 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
481         }
482 out:
483         return fc;
484 }
485
486 void fuse_conn_put(struct fuse_conn *fc)
487 {
488         if (atomic_dec_and_test(&fc->count)) {
489                 if (fc->destroy_req)
490                         fuse_request_free(fc->destroy_req);
491                 mutex_destroy(&fc->inst_mutex);
492                 bdi_destroy(&fc->bdi);
493                 kfree(fc);
494         }
495 }
496
497 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
498 {
499         atomic_inc(&fc->count);
500         return fc;
501 }
502
503 static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
504 {
505         struct fuse_attr attr;
506         memset(&attr, 0, sizeof(attr));
507
508         attr.mode = mode;
509         attr.ino = FUSE_ROOT_ID;
510         attr.nlink = 1;
511         return fuse_iget(sb, 1, 0, &attr, 0, 0);
512 }
513
514 static const struct super_operations fuse_super_operations = {
515         .alloc_inode    = fuse_alloc_inode,
516         .destroy_inode  = fuse_destroy_inode,
517         .clear_inode    = fuse_clear_inode,
518         .drop_inode     = generic_delete_inode,
519         .remount_fs     = fuse_remount_fs,
520         .put_super      = fuse_put_super,
521         .umount_begin   = fuse_umount_begin,
522         .statfs         = fuse_statfs,
523         .show_options   = fuse_show_options,
524 };
525
526 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
527 {
528         struct fuse_init_out *arg = &req->misc.init_out;
529
530         if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
531                 fc->conn_error = 1;
532         else {
533                 unsigned long ra_pages;
534
535                 if (arg->minor >= 6) {
536                         ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
537                         if (arg->flags & FUSE_ASYNC_READ)
538                                 fc->async_read = 1;
539                         if (!(arg->flags & FUSE_POSIX_LOCKS))
540                                 fc->no_lock = 1;
541                         if (arg->flags & FUSE_ATOMIC_O_TRUNC)
542                                 fc->atomic_o_trunc = 1;
543                 } else {
544                         ra_pages = fc->max_read / PAGE_CACHE_SIZE;
545                         fc->no_lock = 1;
546                 }
547
548                 fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
549                 fc->minor = arg->minor;
550                 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
551                 fc->conn_init = 1;
552         }
553         fuse_put_request(fc, req);
554         fc->blocked = 0;
555         wake_up_all(&fc->blocked_waitq);
556 }
557
558 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
559 {
560         struct fuse_init_in *arg = &req->misc.init_in;
561
562         arg->major = FUSE_KERNEL_VERSION;
563         arg->minor = FUSE_KERNEL_MINOR_VERSION;
564         arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
565         arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC;
566         req->in.h.opcode = FUSE_INIT;
567         req->in.numargs = 1;
568         req->in.args[0].size = sizeof(*arg);
569         req->in.args[0].value = arg;
570         req->out.numargs = 1;
571         /* Variable length arguement used for backward compatibility
572            with interface version < 7.5.  Rest of init_out is zeroed
573            by do_get_request(), so a short reply is not a problem */
574         req->out.argvar = 1;
575         req->out.args[0].size = sizeof(struct fuse_init_out);
576         req->out.args[0].value = &req->misc.init_out;
577         req->end = process_init_reply;
578         request_send_background(fc, req);
579 }
580
581 static u64 conn_id(void)
582 {
583         static u64 ctr = 1;
584         return ctr++;
585 }
586
587 static int fuse_fill_super(struct super_block *sb, void *data, int silent)
588 {
589         struct fuse_conn *fc;
590         struct inode *root;
591         struct fuse_mount_data d;
592         struct file *file;
593         struct dentry *root_dentry;
594         struct fuse_req *init_req;
595         int err;
596         int is_bdev = sb->s_bdev != NULL;
597
598         if (sb->s_flags & MS_MANDLOCK)
599                 return -EINVAL;
600
601         if (!parse_fuse_opt((char *) data, &d, is_bdev))
602                 return -EINVAL;
603
604         if (is_bdev) {
605 #ifdef CONFIG_BLOCK
606                 if (!sb_set_blocksize(sb, d.blksize))
607                         return -EINVAL;
608 #endif
609         } else {
610                 sb->s_blocksize = PAGE_CACHE_SIZE;
611                 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
612         }
613         sb->s_magic = FUSE_SUPER_MAGIC;
614         sb->s_op = &fuse_super_operations;
615         sb->s_maxbytes = MAX_LFS_FILESIZE;
616
617         file = fget(d.fd);
618         if (!file)
619                 return -EINVAL;
620
621         if (file->f_op != &fuse_dev_operations)
622                 return -EINVAL;
623
624         fc = new_conn();
625         if (!fc)
626                 return -ENOMEM;
627
628         fc->flags = d.flags;
629         fc->user_id = d.user_id;
630         fc->group_id = d.group_id;
631         fc->max_read = d.max_read;
632
633         /* Used by get_root_inode() */
634         sb->s_fs_info = fc;
635
636         err = -ENOMEM;
637         root = get_root_inode(sb, d.rootmode);
638         if (!root)
639                 goto err;
640
641         root_dentry = d_alloc_root(root);
642         if (!root_dentry) {
643                 iput(root);
644                 goto err;
645         }
646
647         init_req = fuse_request_alloc();
648         if (!init_req)
649                 goto err_put_root;
650
651         if (is_bdev) {
652                 fc->destroy_req = fuse_request_alloc();
653                 if (!fc->destroy_req)
654                         goto err_put_root;
655         }
656
657         mutex_lock(&fuse_mutex);
658         err = -EINVAL;
659         if (file->private_data)
660                 goto err_unlock;
661
662         fc->id = conn_id();
663         err = fuse_ctl_add_conn(fc);
664         if (err)
665                 goto err_unlock;
666
667         list_add_tail(&fc->entry, &fuse_conn_list);
668         sb->s_root = root_dentry;
669         fc->connected = 1;
670         file->private_data = fuse_conn_get(fc);
671         mutex_unlock(&fuse_mutex);
672         /*
673          * atomic_dec_and_test() in fput() provides the necessary
674          * memory barrier for file->private_data to be visible on all
675          * CPUs after this
676          */
677         fput(file);
678
679         fuse_send_init(fc, init_req);
680
681         return 0;
682
683  err_unlock:
684         mutex_unlock(&fuse_mutex);
685         fuse_request_free(init_req);
686  err_put_root:
687         dput(root_dentry);
688  err:
689         fput(file);
690         fuse_conn_put(fc);
691         return err;
692 }
693
694 static int fuse_get_sb(struct file_system_type *fs_type,
695                        int flags, const char *dev_name,
696                        void *raw_data, struct vfsmount *mnt)
697 {
698         return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
699 }
700
701 static struct file_system_type fuse_fs_type = {
702         .owner          = THIS_MODULE,
703         .name           = "fuse",
704         .fs_flags       = FS_HAS_SUBTYPE,
705         .get_sb         = fuse_get_sb,
706         .kill_sb        = kill_anon_super,
707 };
708
709 #ifdef CONFIG_BLOCK
710 static int fuse_get_sb_blk(struct file_system_type *fs_type,
711                            int flags, const char *dev_name,
712                            void *raw_data, struct vfsmount *mnt)
713 {
714         return get_sb_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super,
715                            mnt);
716 }
717
718 static struct file_system_type fuseblk_fs_type = {
719         .owner          = THIS_MODULE,
720         .name           = "fuseblk",
721         .get_sb         = fuse_get_sb_blk,
722         .kill_sb        = kill_block_super,
723         .fs_flags       = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
724 };
725
726 static inline int register_fuseblk(void)
727 {
728         return register_filesystem(&fuseblk_fs_type);
729 }
730
731 static inline void unregister_fuseblk(void)
732 {
733         unregister_filesystem(&fuseblk_fs_type);
734 }
735 #else
736 static inline int register_fuseblk(void)
737 {
738         return 0;
739 }
740
741 static inline void unregister_fuseblk(void)
742 {
743 }
744 #endif
745
746 static void fuse_inode_init_once(struct kmem_cache *cachep, void *foo)
747 {
748         struct inode * inode = foo;
749
750         inode_init_once(inode);
751 }
752
753 static int __init fuse_fs_init(void)
754 {
755         int err;
756
757         err = register_filesystem(&fuse_fs_type);
758         if (err)
759                 goto out;
760
761         err = register_fuseblk();
762         if (err)
763                 goto out_unreg;
764
765         fuse_inode_cachep = kmem_cache_create("fuse_inode",
766                                               sizeof(struct fuse_inode),
767                                               0, SLAB_HWCACHE_ALIGN,
768                                               fuse_inode_init_once);
769         err = -ENOMEM;
770         if (!fuse_inode_cachep)
771                 goto out_unreg2;
772
773         return 0;
774
775  out_unreg2:
776         unregister_fuseblk();
777  out_unreg:
778         unregister_filesystem(&fuse_fs_type);
779  out:
780         return err;
781 }
782
783 static void fuse_fs_cleanup(void)
784 {
785         unregister_filesystem(&fuse_fs_type);
786         unregister_fuseblk();
787         kmem_cache_destroy(fuse_inode_cachep);
788 }
789
790 static struct kobject *fuse_kobj;
791 static struct kobject *connections_kobj;
792
793 static int fuse_sysfs_init(void)
794 {
795         int err;
796
797         fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
798         if (!fuse_kobj) {
799                 err = -ENOMEM;
800                 goto out_err;
801         }
802
803         connections_kobj = kobject_create_and_add("connections", fuse_kobj);
804         if (!connections_kobj) {
805                 err = -ENOMEM;
806                 goto out_fuse_unregister;
807         }
808
809         return 0;
810
811  out_fuse_unregister:
812         kobject_put(fuse_kobj);
813  out_err:
814         return err;
815 }
816
817 static void fuse_sysfs_cleanup(void)
818 {
819         kobject_put(connections_kobj);
820         kobject_put(fuse_kobj);
821 }
822
823 static int __init fuse_init(void)
824 {
825         int res;
826
827         printk("fuse init (API version %i.%i)\n",
828                FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
829
830         INIT_LIST_HEAD(&fuse_conn_list);
831         res = fuse_fs_init();
832         if (res)
833                 goto err;
834
835         res = fuse_dev_init();
836         if (res)
837                 goto err_fs_cleanup;
838
839         res = fuse_sysfs_init();
840         if (res)
841                 goto err_dev_cleanup;
842
843         res = fuse_ctl_init();
844         if (res)
845                 goto err_sysfs_cleanup;
846
847         return 0;
848
849  err_sysfs_cleanup:
850         fuse_sysfs_cleanup();
851  err_dev_cleanup:
852         fuse_dev_cleanup();
853  err_fs_cleanup:
854         fuse_fs_cleanup();
855  err:
856         return res;
857 }
858
859 static void __exit fuse_exit(void)
860 {
861         printk(KERN_DEBUG "fuse exit\n");
862
863         fuse_ctl_cleanup();
864         fuse_sysfs_cleanup();
865         fuse_fs_cleanup();
866         fuse_dev_cleanup();
867 }
868
869 module_init(fuse_init);
870 module_exit(fuse_exit);