2 FUSE: Filesystem in Userspace
3 Copyright (C) 2001-2005 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/mount.h>
15 #include <linux/seq_file.h>
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/parser.h>
19 #include <linux/statfs.h>
21 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
22 MODULE_DESCRIPTION("Filesystem in Userspace");
23 MODULE_LICENSE("GPL");
26 static kmem_cache_t
*fuse_inode_cachep
;
28 #define FUSE_SUPER_MAGIC 0x65735546
30 struct fuse_mount_data
{
35 unsigned fd_present
: 1;
36 unsigned rootmode_present
: 1;
37 unsigned user_id_present
: 1;
38 unsigned group_id_present
: 1;
43 static struct inode
*fuse_alloc_inode(struct super_block
*sb
)
46 struct fuse_inode
*fi
;
48 inode
= kmem_cache_alloc(fuse_inode_cachep
, SLAB_KERNEL
);
52 fi
= get_fuse_inode(inode
);
53 fi
->i_time
= jiffies
- 1;
56 fi
->forget_req
= fuse_request_alloc();
57 if (!fi
->forget_req
) {
58 kmem_cache_free(fuse_inode_cachep
, inode
);
65 static void fuse_destroy_inode(struct inode
*inode
)
67 struct fuse_inode
*fi
= get_fuse_inode(inode
);
69 fuse_request_free(fi
->forget_req
);
70 kmem_cache_free(fuse_inode_cachep
, inode
);
73 static void fuse_read_inode(struct inode
*inode
)
78 void fuse_send_forget(struct fuse_conn
*fc
, struct fuse_req
*req
,
79 unsigned long nodeid
, u64 nlookup
)
81 struct fuse_forget_in
*inarg
= &req
->misc
.forget_in
;
82 inarg
->nlookup
= nlookup
;
83 req
->in
.h
.opcode
= FUSE_FORGET
;
84 req
->in
.h
.nodeid
= nodeid
;
86 req
->in
.args
[0].size
= sizeof(struct fuse_forget_in
);
87 req
->in
.args
[0].value
= inarg
;
88 request_send_noreply(fc
, req
);
91 static void fuse_clear_inode(struct inode
*inode
)
93 if (inode
->i_sb
->s_flags
& MS_ACTIVE
) {
94 struct fuse_conn
*fc
= get_fuse_conn(inode
);
95 struct fuse_inode
*fi
= get_fuse_inode(inode
);
96 fuse_send_forget(fc
, fi
->forget_req
, fi
->nodeid
, fi
->nlookup
);
97 fi
->forget_req
= NULL
;
101 void fuse_change_attributes(struct inode
*inode
, struct fuse_attr
*attr
)
103 if (S_ISREG(inode
->i_mode
) && i_size_read(inode
) != attr
->size
)
104 invalidate_inode_pages(inode
->i_mapping
);
106 inode
->i_ino
= attr
->ino
;
107 inode
->i_mode
= (inode
->i_mode
& S_IFMT
) + (attr
->mode
& 07777);
108 inode
->i_nlink
= attr
->nlink
;
109 inode
->i_uid
= attr
->uid
;
110 inode
->i_gid
= attr
->gid
;
111 i_size_write(inode
, attr
->size
);
112 inode
->i_blksize
= PAGE_CACHE_SIZE
;
113 inode
->i_blocks
= attr
->blocks
;
114 inode
->i_atime
.tv_sec
= attr
->atime
;
115 inode
->i_atime
.tv_nsec
= attr
->atimensec
;
116 inode
->i_mtime
.tv_sec
= attr
->mtime
;
117 inode
->i_mtime
.tv_nsec
= attr
->mtimensec
;
118 inode
->i_ctime
.tv_sec
= attr
->ctime
;
119 inode
->i_ctime
.tv_nsec
= attr
->ctimensec
;
122 static void fuse_init_inode(struct inode
*inode
, struct fuse_attr
*attr
)
124 inode
->i_mode
= attr
->mode
& S_IFMT
;
125 i_size_write(inode
, attr
->size
);
126 if (S_ISREG(inode
->i_mode
)) {
127 fuse_init_common(inode
);
128 fuse_init_file_inode(inode
);
129 } else if (S_ISDIR(inode
->i_mode
))
130 fuse_init_dir(inode
);
131 else if (S_ISLNK(inode
->i_mode
))
132 fuse_init_symlink(inode
);
133 else if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
) ||
134 S_ISFIFO(inode
->i_mode
) || S_ISSOCK(inode
->i_mode
)) {
135 fuse_init_common(inode
);
136 init_special_inode(inode
, inode
->i_mode
,
137 new_decode_dev(attr
->rdev
));
142 static int fuse_inode_eq(struct inode
*inode
, void *_nodeidp
)
144 unsigned long nodeid
= *(unsigned long *) _nodeidp
;
145 if (get_node_id(inode
) == nodeid
)
151 static int fuse_inode_set(struct inode
*inode
, void *_nodeidp
)
153 unsigned long nodeid
= *(unsigned long *) _nodeidp
;
154 get_fuse_inode(inode
)->nodeid
= nodeid
;
158 struct inode
*fuse_iget(struct super_block
*sb
, unsigned long nodeid
,
159 int generation
, struct fuse_attr
*attr
)
162 struct fuse_inode
*fi
;
163 struct fuse_conn
*fc
= get_fuse_conn_super(sb
);
167 inode
= iget5_locked(sb
, nodeid
, fuse_inode_eq
, fuse_inode_set
, &nodeid
);
171 if ((inode
->i_state
& I_NEW
)) {
172 inode
->i_flags
|= S_NOATIME
|S_NOCMTIME
;
173 inode
->i_generation
= generation
;
174 inode
->i_data
.backing_dev_info
= &fc
->bdi
;
175 fuse_init_inode(inode
, attr
);
176 unlock_new_inode(inode
);
177 } else if ((inode
->i_mode
^ attr
->mode
) & S_IFMT
) {
179 /* Inode has changed type, any I/O on the old should fail */
180 make_bad_inode(inode
);
186 fi
= get_fuse_inode(inode
);
188 fuse_change_attributes(inode
, attr
);
192 static void fuse_put_super(struct super_block
*sb
)
194 struct fuse_conn
*fc
= get_fuse_conn_super(sb
);
196 down_write(&fc
->sbput_sem
);
197 while (!list_empty(&fc
->background
))
198 fuse_release_background(list_entry(fc
->background
.next
,
199 struct fuse_req
, bg_entry
));
201 spin_lock(&fuse_lock
);
206 /* Flush all readers on this fs */
207 wake_up_all(&fc
->waitq
);
208 up_write(&fc
->sbput_sem
);
209 fuse_release_conn(fc
);
210 spin_unlock(&fuse_lock
);
213 static void convert_fuse_statfs(struct kstatfs
*stbuf
, struct fuse_kstatfs
*attr
)
215 stbuf
->f_type
= FUSE_SUPER_MAGIC
;
216 stbuf
->f_bsize
= attr
->bsize
;
217 stbuf
->f_frsize
= attr
->frsize
;
218 stbuf
->f_blocks
= attr
->blocks
;
219 stbuf
->f_bfree
= attr
->bfree
;
220 stbuf
->f_bavail
= attr
->bavail
;
221 stbuf
->f_files
= attr
->files
;
222 stbuf
->f_ffree
= attr
->ffree
;
223 stbuf
->f_namelen
= attr
->namelen
;
224 /* fsid is left zero */
227 static int fuse_statfs(struct super_block
*sb
, struct kstatfs
*buf
)
229 struct fuse_conn
*fc
= get_fuse_conn_super(sb
);
230 struct fuse_req
*req
;
231 struct fuse_statfs_out outarg
;
234 req
= fuse_get_request(fc
);
238 memset(&outarg
, 0, sizeof(outarg
));
240 req
->in
.h
.opcode
= FUSE_STATFS
;
241 req
->out
.numargs
= 1;
242 req
->out
.args
[0].size
=
243 fc
->minor
< 4 ? FUSE_COMPAT_STATFS_SIZE
: sizeof(outarg
);
244 req
->out
.args
[0].value
= &outarg
;
245 request_send(fc
, req
);
246 err
= req
->out
.h
.error
;
248 convert_fuse_statfs(buf
, &outarg
.st
);
249 fuse_put_request(fc
, req
);
258 OPT_DEFAULT_PERMISSIONS
,
264 static match_table_t tokens
= {
266 {OPT_ROOTMODE
, "rootmode=%o"},
267 {OPT_USER_ID
, "user_id=%u"},
268 {OPT_GROUP_ID
, "group_id=%u"},
269 {OPT_DEFAULT_PERMISSIONS
, "default_permissions"},
270 {OPT_ALLOW_OTHER
, "allow_other"},
271 {OPT_MAX_READ
, "max_read=%u"},
275 static int parse_fuse_opt(char *opt
, struct fuse_mount_data
*d
)
278 memset(d
, 0, sizeof(struct fuse_mount_data
));
281 while ((p
= strsep(&opt
, ",")) != NULL
) {
284 substring_t args
[MAX_OPT_ARGS
];
288 token
= match_token(p
, tokens
, args
);
291 if (match_int(&args
[0], &value
))
298 if (match_octal(&args
[0], &value
))
301 d
->rootmode_present
= 1;
305 if (match_int(&args
[0], &value
))
308 d
->user_id_present
= 1;
312 if (match_int(&args
[0], &value
))
315 d
->group_id_present
= 1;
318 case OPT_DEFAULT_PERMISSIONS
:
319 d
->flags
|= FUSE_DEFAULT_PERMISSIONS
;
322 case OPT_ALLOW_OTHER
:
323 d
->flags
|= FUSE_ALLOW_OTHER
;
327 if (match_int(&args
[0], &value
))
337 if (!d
->fd_present
|| !d
->rootmode_present
||
338 !d
->user_id_present
|| !d
->group_id_present
)
344 static int fuse_show_options(struct seq_file
*m
, struct vfsmount
*mnt
)
346 struct fuse_conn
*fc
= get_fuse_conn_super(mnt
->mnt_sb
);
348 seq_printf(m
, ",user_id=%u", fc
->user_id
);
349 seq_printf(m
, ",group_id=%u", fc
->group_id
);
350 if (fc
->flags
& FUSE_DEFAULT_PERMISSIONS
)
351 seq_puts(m
, ",default_permissions");
352 if (fc
->flags
& FUSE_ALLOW_OTHER
)
353 seq_puts(m
, ",allow_other");
354 if (fc
->max_read
!= ~0)
355 seq_printf(m
, ",max_read=%u", fc
->max_read
);
359 static void free_conn(struct fuse_conn
*fc
)
361 while (!list_empty(&fc
->unused_list
)) {
362 struct fuse_req
*req
;
363 req
= list_entry(fc
->unused_list
.next
, struct fuse_req
, list
);
364 list_del(&req
->list
);
365 fuse_request_free(req
);
370 /* Must be called with the fuse lock held */
371 void fuse_release_conn(struct fuse_conn
*fc
)
378 static struct fuse_conn
*new_conn(void)
380 struct fuse_conn
*fc
;
382 fc
= kmalloc(sizeof(*fc
), GFP_KERNEL
);
385 memset(fc
, 0, sizeof(*fc
));
386 init_waitqueue_head(&fc
->waitq
);
387 INIT_LIST_HEAD(&fc
->pending
);
388 INIT_LIST_HEAD(&fc
->processing
);
389 INIT_LIST_HEAD(&fc
->unused_list
);
390 INIT_LIST_HEAD(&fc
->background
);
391 sema_init(&fc
->outstanding_sem
, 0);
392 init_rwsem(&fc
->sbput_sem
);
393 for (i
= 0; i
< FUSE_MAX_OUTSTANDING
; i
++) {
394 struct fuse_req
*req
= fuse_request_alloc();
399 list_add(&req
->list
, &fc
->unused_list
);
401 fc
->bdi
.ra_pages
= (VM_MAX_READAHEAD
* 1024) / PAGE_CACHE_SIZE
;
402 fc
->bdi
.unplug_io_fn
= default_unplug_io_fn
;
408 static struct fuse_conn
*get_conn(struct file
*file
, struct super_block
*sb
)
410 struct fuse_conn
*fc
;
412 if (file
->f_op
!= &fuse_dev_operations
)
413 return ERR_PTR(-EINVAL
);
416 return ERR_PTR(-ENOMEM
);
417 spin_lock(&fuse_lock
);
418 if (file
->private_data
) {
420 fc
= ERR_PTR(-EINVAL
);
422 file
->private_data
= fc
;
423 *get_fuse_conn_super_p(sb
) = fc
;
428 spin_unlock(&fuse_lock
);
432 static struct inode
*get_root_inode(struct super_block
*sb
, unsigned mode
)
434 struct fuse_attr attr
;
435 memset(&attr
, 0, sizeof(attr
));
438 attr
.ino
= FUSE_ROOT_ID
;
439 return fuse_iget(sb
, 1, 0, &attr
);
442 static struct super_operations fuse_super_operations
= {
443 .alloc_inode
= fuse_alloc_inode
,
444 .destroy_inode
= fuse_destroy_inode
,
445 .read_inode
= fuse_read_inode
,
446 .clear_inode
= fuse_clear_inode
,
447 .put_super
= fuse_put_super
,
448 .statfs
= fuse_statfs
,
449 .show_options
= fuse_show_options
,
452 static int fuse_fill_super(struct super_block
*sb
, void *data
, int silent
)
454 struct fuse_conn
*fc
;
456 struct fuse_mount_data d
;
460 if (!parse_fuse_opt((char *) data
, &d
))
463 sb
->s_blocksize
= PAGE_CACHE_SIZE
;
464 sb
->s_blocksize_bits
= PAGE_CACHE_SHIFT
;
465 sb
->s_magic
= FUSE_SUPER_MAGIC
;
466 sb
->s_op
= &fuse_super_operations
;
467 sb
->s_maxbytes
= MAX_LFS_FILESIZE
;
473 fc
= get_conn(file
, sb
);
479 fc
->user_id
= d
.user_id
;
480 fc
->group_id
= d
.group_id
;
481 fc
->max_read
= d
.max_read
;
482 if (fc
->max_read
/ PAGE_CACHE_SIZE
< fc
->bdi
.ra_pages
)
483 fc
->bdi
.ra_pages
= fc
->max_read
/ PAGE_CACHE_SIZE
;
486 root
= get_root_inode(sb
, d
.rootmode
);
490 sb
->s_root
= d_alloc_root(root
);
499 spin_lock(&fuse_lock
);
500 fuse_release_conn(fc
);
501 spin_unlock(&fuse_lock
);
505 static struct super_block
*fuse_get_sb(struct file_system_type
*fs_type
,
506 int flags
, const char *dev_name
,
509 return get_sb_nodev(fs_type
, flags
, raw_data
, fuse_fill_super
);
512 static struct file_system_type fuse_fs_type
= {
513 .owner
= THIS_MODULE
,
515 .get_sb
= fuse_get_sb
,
516 .kill_sb
= kill_anon_super
,
519 static void fuse_inode_init_once(void *foo
, kmem_cache_t
*cachep
,
522 struct inode
* inode
= foo
;
524 if ((flags
& (SLAB_CTOR_VERIFY
|SLAB_CTOR_CONSTRUCTOR
)) ==
525 SLAB_CTOR_CONSTRUCTOR
)
526 inode_init_once(inode
);
529 static int __init
fuse_fs_init(void)
533 err
= register_filesystem(&fuse_fs_type
);
535 printk("fuse: failed to register filesystem\n");
537 fuse_inode_cachep
= kmem_cache_create("fuse_inode",
538 sizeof(struct fuse_inode
),
539 0, SLAB_HWCACHE_ALIGN
,
540 fuse_inode_init_once
, NULL
);
541 if (!fuse_inode_cachep
) {
542 unregister_filesystem(&fuse_fs_type
);
550 static void fuse_fs_cleanup(void)
552 unregister_filesystem(&fuse_fs_type
);
553 kmem_cache_destroy(fuse_inode_cachep
);
556 static int __init
fuse_init(void)
560 printk("fuse init (API version %i.%i)\n",
561 FUSE_KERNEL_VERSION
, FUSE_KERNEL_MINOR_VERSION
);
563 spin_lock_init(&fuse_lock
);
564 res
= fuse_fs_init();
568 res
= fuse_dev_init();
580 static void __exit
fuse_exit(void)
582 printk(KERN_DEBUG
"fuse exit\n");
588 module_init(fuse_init
);
589 module_exit(fuse_exit
);