2 FUSE: Filesystem in Userspace
3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
5 This program can be distributed under the terms of the GNU GPL.
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 #include <linux/exportfs.h>
23 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
24 MODULE_DESCRIPTION("Filesystem in Userspace");
25 MODULE_LICENSE("GPL");
27 static struct kmem_cache *fuse_inode_cachep;
28 struct list_head fuse_conn_list;
29 DEFINE_MUTEX(fuse_mutex);
31 #define FUSE_SUPER_MAGIC 0x65735546
33 #define FUSE_DEFAULT_BLKSIZE 512
35 struct fuse_mount_data {
40 unsigned fd_present:1;
41 unsigned rootmode_present:1;
42 unsigned user_id_present:1;
43 unsigned group_id_present:1;
49 static struct inode *fuse_alloc_inode(struct super_block *sb)
52 struct fuse_inode *fi;
54 inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
58 fi = get_fuse_inode(inode);
64 INIT_LIST_HEAD(&fi->write_files);
65 INIT_LIST_HEAD(&fi->queued_writes);
66 INIT_LIST_HEAD(&fi->writepages);
67 init_waitqueue_head(&fi->page_waitq);
68 fi->forget_req = fuse_request_alloc();
69 if (!fi->forget_req) {
70 kmem_cache_free(fuse_inode_cachep, inode);
77 static void fuse_destroy_inode(struct inode *inode)
79 struct fuse_inode *fi = get_fuse_inode(inode);
80 BUG_ON(!list_empty(&fi->write_files));
81 BUG_ON(!list_empty(&fi->queued_writes));
83 fuse_request_free(fi->forget_req);
84 kmem_cache_free(fuse_inode_cachep, inode);
87 void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
88 u64 nodeid, u64 nlookup)
90 struct fuse_forget_in *inarg = &req->misc.forget_in;
91 inarg->nlookup = nlookup;
92 req->in.h.opcode = FUSE_FORGET;
93 req->in.h.nodeid = nodeid;
95 req->in.args[0].size = sizeof(struct fuse_forget_in);
96 req->in.args[0].value = inarg;
97 fuse_request_send_noreply(fc, req);
100 static void fuse_clear_inode(struct inode *inode)
102 if (inode->i_sb->s_flags & MS_ACTIVE) {
103 struct fuse_conn *fc = get_fuse_conn(inode);
104 struct fuse_inode *fi = get_fuse_inode(inode);
105 fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
106 fi->forget_req = NULL;
110 static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
112 if (*flags & MS_MANDLOCK)
118 void fuse_truncate(struct address_space *mapping, loff_t offset)
120 /* See vmtruncate() */
121 unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
122 truncate_inode_pages(mapping, offset);
123 unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
126 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
129 struct fuse_conn *fc = get_fuse_conn(inode);
130 struct fuse_inode *fi = get_fuse_inode(inode);
132 fi->attr_version = ++fc->attr_version;
133 fi->i_time = attr_valid;
135 inode->i_ino = attr->ino;
136 inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
137 inode->i_nlink = attr->nlink;
138 inode->i_uid = attr->uid;
139 inode->i_gid = attr->gid;
140 inode->i_blocks = attr->blocks;
141 inode->i_atime.tv_sec = attr->atime;
142 inode->i_atime.tv_nsec = attr->atimensec;
143 inode->i_mtime.tv_sec = attr->mtime;
144 inode->i_mtime.tv_nsec = attr->mtimensec;
145 inode->i_ctime.tv_sec = attr->ctime;
146 inode->i_ctime.tv_nsec = attr->ctimensec;
148 if (attr->blksize != 0)
149 inode->i_blkbits = ilog2(attr->blksize);
151 inode->i_blkbits = inode->i_sb->s_blocksize_bits;
154 * Don't set the sticky bit in i_mode, unless we want the VFS
155 * to check permissions. This prevents failures due to the
156 * check in may_delete().
158 fi->orig_i_mode = inode->i_mode;
159 if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
160 inode->i_mode &= ~S_ISVTX;
163 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
164 u64 attr_valid, u64 attr_version)
166 struct fuse_conn *fc = get_fuse_conn(inode);
167 struct fuse_inode *fi = get_fuse_inode(inode);
170 spin_lock(&fc->lock);
171 if (attr_version != 0 && fi->attr_version > attr_version) {
172 spin_unlock(&fc->lock);
176 fuse_change_attributes_common(inode, attr, attr_valid);
178 oldsize = inode->i_size;
179 i_size_write(inode, attr->size);
180 spin_unlock(&fc->lock);
182 if (S_ISREG(inode->i_mode) && oldsize != attr->size) {
183 if (attr->size < oldsize)
184 fuse_truncate(inode->i_mapping, attr->size);
185 invalidate_inode_pages2(inode->i_mapping);
189 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
191 inode->i_mode = attr->mode & S_IFMT;
192 inode->i_size = attr->size;
193 if (S_ISREG(inode->i_mode)) {
194 fuse_init_common(inode);
195 fuse_init_file_inode(inode);
196 } else if (S_ISDIR(inode->i_mode))
197 fuse_init_dir(inode);
198 else if (S_ISLNK(inode->i_mode))
199 fuse_init_symlink(inode);
200 else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
201 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
202 fuse_init_common(inode);
203 init_special_inode(inode, inode->i_mode,
204 new_decode_dev(attr->rdev));
209 static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
211 u64 nodeid = *(u64 *) _nodeidp;
212 if (get_node_id(inode) == nodeid)
218 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
220 u64 nodeid = *(u64 *) _nodeidp;
221 get_fuse_inode(inode)->nodeid = nodeid;
225 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
226 int generation, struct fuse_attr *attr,
227 u64 attr_valid, u64 attr_version)
230 struct fuse_inode *fi;
231 struct fuse_conn *fc = get_fuse_conn_super(sb);
234 inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
238 if ((inode->i_state & I_NEW)) {
239 inode->i_flags |= S_NOATIME|S_NOCMTIME;
240 inode->i_generation = generation;
241 inode->i_data.backing_dev_info = &fc->bdi;
242 fuse_init_inode(inode, attr);
243 unlock_new_inode(inode);
244 } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
245 /* Inode has changed type, any I/O on the old should fail */
246 make_bad_inode(inode);
251 fi = get_fuse_inode(inode);
252 spin_lock(&fc->lock);
254 spin_unlock(&fc->lock);
255 fuse_change_attributes(inode, attr, attr_valid, attr_version);
260 static void fuse_umount_begin(struct super_block *sb)
262 fuse_abort_conn(get_fuse_conn_super(sb));
265 static void fuse_send_destroy(struct fuse_conn *fc)
267 struct fuse_req *req = fc->destroy_req;
268 if (req && fc->conn_init) {
269 fc->destroy_req = NULL;
270 req->in.h.opcode = FUSE_DESTROY;
272 fuse_request_send(fc, req);
273 fuse_put_request(fc, req);
277 static void fuse_bdi_destroy(struct fuse_conn *fc)
279 if (fc->bdi_initialized)
280 bdi_destroy(&fc->bdi);
283 static void fuse_conn_kill(struct fuse_conn *fc)
285 spin_lock(&fc->lock);
288 spin_unlock(&fc->lock);
289 /* Flush all readers on this fs */
290 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
291 wake_up_all(&fc->waitq);
292 wake_up_all(&fc->blocked_waitq);
293 wake_up_all(&fc->reserved_req_waitq);
294 mutex_lock(&fuse_mutex);
295 list_del(&fc->entry);
296 fuse_ctl_remove_conn(fc);
297 mutex_unlock(&fuse_mutex);
298 fuse_bdi_destroy(fc);
301 static void fuse_put_super(struct super_block *sb)
303 struct fuse_conn *fc = get_fuse_conn_super(sb);
305 fuse_send_destroy(fc);
310 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
312 stbuf->f_type = FUSE_SUPER_MAGIC;
313 stbuf->f_bsize = attr->bsize;
314 stbuf->f_frsize = attr->frsize;
315 stbuf->f_blocks = attr->blocks;
316 stbuf->f_bfree = attr->bfree;
317 stbuf->f_bavail = attr->bavail;
318 stbuf->f_files = attr->files;
319 stbuf->f_ffree = attr->ffree;
320 stbuf->f_namelen = attr->namelen;
321 /* fsid is left zero */
324 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
326 struct super_block *sb = dentry->d_sb;
327 struct fuse_conn *fc = get_fuse_conn_super(sb);
328 struct fuse_req *req;
329 struct fuse_statfs_out outarg;
332 if (!fuse_allow_task(fc, current)) {
333 buf->f_type = FUSE_SUPER_MAGIC;
337 req = fuse_get_req(fc);
341 memset(&outarg, 0, sizeof(outarg));
343 req->in.h.opcode = FUSE_STATFS;
344 req->in.h.nodeid = get_node_id(dentry->d_inode);
345 req->out.numargs = 1;
346 req->out.args[0].size =
347 fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
348 req->out.args[0].value = &outarg;
349 fuse_request_send(fc, req);
350 err = req->out.h.error;
352 convert_fuse_statfs(buf, &outarg.st);
353 fuse_put_request(fc, req);
362 OPT_DEFAULT_PERMISSIONS,
369 static const match_table_t tokens = {
371 {OPT_ROOTMODE, "rootmode=%o"},
372 {OPT_USER_ID, "user_id=%u"},
373 {OPT_GROUP_ID, "group_id=%u"},
374 {OPT_DEFAULT_PERMISSIONS, "default_permissions"},
375 {OPT_ALLOW_OTHER, "allow_other"},
376 {OPT_MAX_READ, "max_read=%u"},
377 {OPT_BLKSIZE, "blksize=%u"},
381 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
384 memset(d, 0, sizeof(struct fuse_mount_data));
386 d->blksize = FUSE_DEFAULT_BLKSIZE;
388 while ((p = strsep(&opt, ",")) != NULL) {
391 substring_t args[MAX_OPT_ARGS];
395 token = match_token(p, tokens, args);
398 if (match_int(&args[0], &value))
405 if (match_octal(&args[0], &value))
407 if (!fuse_valid_type(value))
410 d->rootmode_present = 1;
414 if (match_int(&args[0], &value))
417 d->user_id_present = 1;
421 if (match_int(&args[0], &value))
424 d->group_id_present = 1;
427 case OPT_DEFAULT_PERMISSIONS:
428 d->flags |= FUSE_DEFAULT_PERMISSIONS;
431 case OPT_ALLOW_OTHER:
432 d->flags |= FUSE_ALLOW_OTHER;
436 if (match_int(&args[0], &value))
442 if (!is_bdev || match_int(&args[0], &value))
452 if (!d->fd_present || !d->rootmode_present ||
453 !d->user_id_present || !d->group_id_present)
459 static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
461 struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
463 seq_printf(m, ",user_id=%u", fc->user_id);
464 seq_printf(m, ",group_id=%u", fc->group_id);
465 if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
466 seq_puts(m, ",default_permissions");
467 if (fc->flags & FUSE_ALLOW_OTHER)
468 seq_puts(m, ",allow_other");
469 if (fc->max_read != ~0)
470 seq_printf(m, ",max_read=%u", fc->max_read);
471 if (mnt->mnt_sb->s_bdev &&
472 mnt->mnt_sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
473 seq_printf(m, ",blksize=%lu", mnt->mnt_sb->s_blocksize);
477 void fuse_conn_init(struct fuse_conn *fc)
479 memset(fc, 0, sizeof(*fc));
480 spin_lock_init(&fc->lock);
481 mutex_init(&fc->inst_mutex);
482 atomic_set(&fc->count, 1);
483 init_waitqueue_head(&fc->waitq);
484 init_waitqueue_head(&fc->blocked_waitq);
485 init_waitqueue_head(&fc->reserved_req_waitq);
486 INIT_LIST_HEAD(&fc->pending);
487 INIT_LIST_HEAD(&fc->processing);
488 INIT_LIST_HEAD(&fc->io);
489 INIT_LIST_HEAD(&fc->interrupts);
490 INIT_LIST_HEAD(&fc->bg_queue);
491 INIT_LIST_HEAD(&fc->entry);
492 atomic_set(&fc->num_waiting, 0);
494 fc->polled_files = RB_ROOT;
497 fc->attr_version = 1;
498 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
500 EXPORT_SYMBOL_GPL(fuse_conn_init);
502 void fuse_conn_put(struct fuse_conn *fc)
504 if (atomic_dec_and_test(&fc->count)) {
506 fuse_request_free(fc->destroy_req);
507 mutex_destroy(&fc->inst_mutex);
512 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
514 atomic_inc(&fc->count);
518 static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
520 struct fuse_attr attr;
521 memset(&attr, 0, sizeof(attr));
524 attr.ino = FUSE_ROOT_ID;
526 return fuse_iget(sb, 1, 0, &attr, 0, 0);
529 struct fuse_inode_handle {
534 static struct dentry *fuse_get_dentry(struct super_block *sb,
535 struct fuse_inode_handle *handle)
537 struct fuse_conn *fc = get_fuse_conn_super(sb);
539 struct dentry *entry;
542 if (handle->nodeid == 0)
545 inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
547 struct fuse_entry_out outarg;
550 if (!fc->export_support)
555 err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
557 if (err && err != -ENOENT)
564 if (get_node_id(inode) != handle->nodeid)
568 if (inode->i_generation != handle->generation)
571 entry = d_obtain_alias(inode);
572 if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID) {
573 entry->d_op = &fuse_dentry_operations;
574 fuse_invalidate_entry_cache(entry);
585 static int fuse_encode_fh(struct dentry *dentry, u32 *fh, int *max_len,
588 struct inode *inode = dentry->d_inode;
589 bool encode_parent = connectable && !S_ISDIR(inode->i_mode);
590 int len = encode_parent ? 6 : 3;
597 nodeid = get_fuse_inode(inode)->nodeid;
598 generation = inode->i_generation;
600 fh[0] = (u32)(nodeid >> 32);
601 fh[1] = (u32)(nodeid & 0xffffffff);
605 struct inode *parent;
607 spin_lock(&dentry->d_lock);
608 parent = dentry->d_parent->d_inode;
609 nodeid = get_fuse_inode(parent)->nodeid;
610 generation = parent->i_generation;
611 spin_unlock(&dentry->d_lock);
613 fh[3] = (u32)(nodeid >> 32);
614 fh[4] = (u32)(nodeid & 0xffffffff);
619 return encode_parent ? 0x82 : 0x81;
622 static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
623 struct fid *fid, int fh_len, int fh_type)
625 struct fuse_inode_handle handle;
627 if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
630 handle.nodeid = (u64) fid->raw[0] << 32;
631 handle.nodeid |= (u64) fid->raw[1];
632 handle.generation = fid->raw[2];
633 return fuse_get_dentry(sb, &handle);
636 static struct dentry *fuse_fh_to_parent(struct super_block *sb,
637 struct fid *fid, int fh_len, int fh_type)
639 struct fuse_inode_handle parent;
641 if (fh_type != 0x82 || fh_len < 6)
644 parent.nodeid = (u64) fid->raw[3] << 32;
645 parent.nodeid |= (u64) fid->raw[4];
646 parent.generation = fid->raw[5];
647 return fuse_get_dentry(sb, &parent);
650 static struct dentry *fuse_get_parent(struct dentry *child)
652 struct inode *child_inode = child->d_inode;
653 struct fuse_conn *fc = get_fuse_conn(child_inode);
655 struct dentry *parent;
656 struct fuse_entry_out outarg;
660 if (!fc->export_support)
661 return ERR_PTR(-ESTALE);
665 err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
666 &name, &outarg, &inode);
669 return ERR_PTR(-ESTALE);
673 parent = d_obtain_alias(inode);
674 if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID) {
675 parent->d_op = &fuse_dentry_operations;
676 fuse_invalidate_entry_cache(parent);
682 static const struct export_operations fuse_export_operations = {
683 .fh_to_dentry = fuse_fh_to_dentry,
684 .fh_to_parent = fuse_fh_to_parent,
685 .encode_fh = fuse_encode_fh,
686 .get_parent = fuse_get_parent,
689 static const struct super_operations fuse_super_operations = {
690 .alloc_inode = fuse_alloc_inode,
691 .destroy_inode = fuse_destroy_inode,
692 .clear_inode = fuse_clear_inode,
693 .drop_inode = generic_delete_inode,
694 .remount_fs = fuse_remount_fs,
695 .put_super = fuse_put_super,
696 .umount_begin = fuse_umount_begin,
697 .statfs = fuse_statfs,
698 .show_options = fuse_show_options,
701 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
703 struct fuse_init_out *arg = &req->misc.init_out;
705 if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
708 unsigned long ra_pages;
710 if (arg->minor >= 6) {
711 ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
712 if (arg->flags & FUSE_ASYNC_READ)
714 if (!(arg->flags & FUSE_POSIX_LOCKS))
716 if (arg->flags & FUSE_ATOMIC_O_TRUNC)
717 fc->atomic_o_trunc = 1;
718 if (arg->minor >= 9) {
719 /* LOOKUP has dependency on proto version */
720 if (arg->flags & FUSE_EXPORT_SUPPORT)
721 fc->export_support = 1;
723 if (arg->flags & FUSE_BIG_WRITES)
726 ra_pages = fc->max_read / PAGE_CACHE_SIZE;
730 fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
731 fc->minor = arg->minor;
732 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
733 fc->max_write = max_t(unsigned, 4096, fc->max_write);
737 wake_up_all(&fc->blocked_waitq);
740 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
742 struct fuse_init_in *arg = &req->misc.init_in;
744 arg->major = FUSE_KERNEL_VERSION;
745 arg->minor = FUSE_KERNEL_MINOR_VERSION;
746 arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
747 arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
748 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES;
749 req->in.h.opcode = FUSE_INIT;
751 req->in.args[0].size = sizeof(*arg);
752 req->in.args[0].value = arg;
753 req->out.numargs = 1;
754 /* Variable length arguement used for backward compatibility
755 with interface version < 7.5. Rest of init_out is zeroed
756 by do_get_request(), so a short reply is not a problem */
758 req->out.args[0].size = sizeof(struct fuse_init_out);
759 req->out.args[0].value = &req->misc.init_out;
760 req->end = process_init_reply;
761 fuse_request_send_background(fc, req);
764 static void fuse_free_conn(struct fuse_conn *fc)
769 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
773 fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
774 fc->bdi.unplug_io_fn = default_unplug_io_fn;
775 /* fuse does it's own writeback accounting */
776 fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB;
778 err = bdi_init(&fc->bdi);
782 fc->bdi_initialized = 1;
785 err = bdi_register(&fc->bdi, NULL, "%u:%u-fuseblk",
786 MAJOR(fc->dev), MINOR(fc->dev));
788 err = bdi_register_dev(&fc->bdi, fc->dev);
795 * For a single fuse filesystem use max 1% of dirty +
796 * writeback threshold.
798 * This gives about 1M of write buffer for memory maps on a
799 * machine with 1G and 10% dirty_ratio, which should be more
802 * Privileged users can raise it by writing to
804 * /sys/class/bdi/<bdi>/max_ratio
806 bdi_set_max_ratio(&fc->bdi, 1);
811 static int fuse_fill_super(struct super_block *sb, void *data, int silent)
813 struct fuse_conn *fc;
815 struct fuse_mount_data d;
817 struct dentry *root_dentry;
818 struct fuse_req *init_req;
820 int is_bdev = sb->s_bdev != NULL;
823 if (sb->s_flags & MS_MANDLOCK)
826 if (!parse_fuse_opt((char *) data, &d, is_bdev))
832 if (!sb_set_blocksize(sb, d.blksize))
836 sb->s_blocksize = PAGE_CACHE_SIZE;
837 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
839 sb->s_magic = FUSE_SUPER_MAGIC;
840 sb->s_op = &fuse_super_operations;
841 sb->s_maxbytes = MAX_LFS_FILESIZE;
842 sb->s_export_op = &fuse_export_operations;
849 if (file->f_op != &fuse_dev_operations)
852 fc = kmalloc(sizeof(*fc), GFP_KERNEL);
860 err = fuse_bdi_init(fc, sb);
864 fc->release = fuse_free_conn;
866 fc->user_id = d.user_id;
867 fc->group_id = d.group_id;
868 fc->max_read = max_t(unsigned, 4096, d.max_read);
870 /* Used by get_root_inode() */
874 root = fuse_get_root_inode(sb, d.rootmode);
878 root_dentry = d_alloc_root(root);
884 init_req = fuse_request_alloc();
889 fc->destroy_req = fuse_request_alloc();
890 if (!fc->destroy_req)
891 goto err_free_init_req;
894 mutex_lock(&fuse_mutex);
896 if (file->private_data)
899 err = fuse_ctl_add_conn(fc);
903 list_add_tail(&fc->entry, &fuse_conn_list);
904 sb->s_root = root_dentry;
906 file->private_data = fuse_conn_get(fc);
907 mutex_unlock(&fuse_mutex);
909 * atomic_dec_and_test() in fput() provides the necessary
910 * memory barrier for file->private_data to be visible on all
915 fuse_send_init(fc, init_req);
920 mutex_unlock(&fuse_mutex);
922 fuse_request_free(init_req);
926 fuse_bdi_destroy(fc);
934 static int fuse_get_sb(struct file_system_type *fs_type,
935 int flags, const char *dev_name,
936 void *raw_data, struct vfsmount *mnt)
938 return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
941 static struct file_system_type fuse_fs_type = {
942 .owner = THIS_MODULE,
944 .fs_flags = FS_HAS_SUBTYPE,
945 .get_sb = fuse_get_sb,
946 .kill_sb = kill_anon_super,
950 static int fuse_get_sb_blk(struct file_system_type *fs_type,
951 int flags, const char *dev_name,
952 void *raw_data, struct vfsmount *mnt)
954 return get_sb_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super,
958 static struct file_system_type fuseblk_fs_type = {
959 .owner = THIS_MODULE,
961 .get_sb = fuse_get_sb_blk,
962 .kill_sb = kill_block_super,
963 .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
966 static inline int register_fuseblk(void)
968 return register_filesystem(&fuseblk_fs_type);
971 static inline void unregister_fuseblk(void)
973 unregister_filesystem(&fuseblk_fs_type);
976 static inline int register_fuseblk(void)
981 static inline void unregister_fuseblk(void)
986 static void fuse_inode_init_once(void *foo)
988 struct inode *inode = foo;
990 inode_init_once(inode);
993 static int __init fuse_fs_init(void)
997 err = register_filesystem(&fuse_fs_type);
1001 err = register_fuseblk();
1005 fuse_inode_cachep = kmem_cache_create("fuse_inode",
1006 sizeof(struct fuse_inode),
1007 0, SLAB_HWCACHE_ALIGN,
1008 fuse_inode_init_once);
1010 if (!fuse_inode_cachep)
1016 unregister_fuseblk();
1018 unregister_filesystem(&fuse_fs_type);
1023 static void fuse_fs_cleanup(void)
1025 unregister_filesystem(&fuse_fs_type);
1026 unregister_fuseblk();
1027 kmem_cache_destroy(fuse_inode_cachep);
1030 static struct kobject *fuse_kobj;
1031 static struct kobject *connections_kobj;
1033 static int fuse_sysfs_init(void)
1037 fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
1043 connections_kobj = kobject_create_and_add("connections", fuse_kobj);
1044 if (!connections_kobj) {
1046 goto out_fuse_unregister;
1051 out_fuse_unregister:
1052 kobject_put(fuse_kobj);
1057 static void fuse_sysfs_cleanup(void)
1059 kobject_put(connections_kobj);
1060 kobject_put(fuse_kobj);
1063 static int __init fuse_init(void)
1067 printk(KERN_INFO "fuse init (API version %i.%i)\n",
1068 FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
1070 INIT_LIST_HEAD(&fuse_conn_list);
1071 res = fuse_fs_init();
1075 res = fuse_dev_init();
1077 goto err_fs_cleanup;
1079 res = fuse_sysfs_init();
1081 goto err_dev_cleanup;
1083 res = fuse_ctl_init();
1085 goto err_sysfs_cleanup;
1090 fuse_sysfs_cleanup();
1099 static void __exit fuse_exit(void)
1101 printk(KERN_DEBUG "fuse exit\n");
1104 fuse_sysfs_cleanup();
1109 module_init(fuse_init);
1110 module_exit(fuse_exit);