This source file includes following definitions.
- fuse_alloc_forget
- fuse_alloc_inode
- fuse_free_inode
- fuse_evict_inode
- fuse_remount_fs
- fuse_squash_ino
- fuse_change_attributes_common
- fuse_change_attributes
- fuse_init_inode
- fuse_inode_eq
- fuse_inode_set
- fuse_iget
- fuse_reverse_inval_inode
- fuse_lock_inode
- fuse_unlock_inode
- fuse_umount_begin
- fuse_send_destroy
- fuse_put_super
- convert_fuse_statfs
- fuse_statfs
- fuse_parse_param
- fuse_free_fc
- fuse_show_options
- fuse_iqueue_init
- fuse_pqueue_init
- fuse_conn_init
- fuse_conn_put
- fuse_conn_get
- fuse_get_root_inode
- fuse_get_dentry
- fuse_encode_fh
- fuse_fh_to_dentry
- fuse_fh_to_parent
- fuse_get_parent
- sanitize_global_limit
- set_global_limit
- process_init_limits
- process_init_reply
- fuse_send_init
- fuse_free_conn
- fuse_bdi_init
- fuse_dev_alloc
- fuse_dev_install
- fuse_dev_alloc_install
- fuse_dev_free
- fuse_fill_super_common
- fuse_fill_super
- fuse_get_tree
- fuse_init_fs_context
- fuse_sb_destroy
- fuse_kill_sb_anon
- fuse_kill_sb_blk
- register_fuseblk
- unregister_fuseblk
- register_fuseblk
- unregister_fuseblk
- fuse_inode_init_once
- fuse_fs_init
- fuse_fs_cleanup
- fuse_sysfs_init
- fuse_sysfs_cleanup
- fuse_init
- fuse_exit
1
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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/fs_context.h>
19 #include <linux/fs_parser.h>
20 #include <linux/statfs.h>
21 #include <linux/random.h>
22 #include <linux/sched.h>
23 #include <linux/exportfs.h>
24 #include <linux/posix_acl.h>
25 #include <linux/pid_namespace.h>
26
27 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
28 MODULE_DESCRIPTION("Filesystem in Userspace");
29 MODULE_LICENSE("GPL");
30
31 static struct kmem_cache *fuse_inode_cachep;
32 struct list_head fuse_conn_list;
33 DEFINE_MUTEX(fuse_mutex);
34
35 static int set_global_limit(const char *val, const struct kernel_param *kp);
36
37 unsigned max_user_bgreq;
38 module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
39 &max_user_bgreq, 0644);
40 __MODULE_PARM_TYPE(max_user_bgreq, "uint");
41 MODULE_PARM_DESC(max_user_bgreq,
42 "Global limit for the maximum number of backgrounded requests an "
43 "unprivileged user can set");
44
45 unsigned max_user_congthresh;
46 module_param_call(max_user_congthresh, set_global_limit, param_get_uint,
47 &max_user_congthresh, 0644);
48 __MODULE_PARM_TYPE(max_user_congthresh, "uint");
49 MODULE_PARM_DESC(max_user_congthresh,
50 "Global limit for the maximum congestion threshold an "
51 "unprivileged user can set");
52
53 #define FUSE_SUPER_MAGIC 0x65735546
54
55 #define FUSE_DEFAULT_BLKSIZE 512
56
57
58 #define FUSE_DEFAULT_MAX_BACKGROUND 12
59
60
61 #define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4)
62
63 #ifdef CONFIG_BLOCK
64 static struct file_system_type fuseblk_fs_type;
65 #endif
66
67 struct fuse_forget_link *fuse_alloc_forget(void)
68 {
69 return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL_ACCOUNT);
70 }
71
72 static struct inode *fuse_alloc_inode(struct super_block *sb)
73 {
74 struct fuse_inode *fi;
75
76 fi = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
77 if (!fi)
78 return NULL;
79
80 fi->i_time = 0;
81 fi->inval_mask = 0;
82 fi->nodeid = 0;
83 fi->nlookup = 0;
84 fi->attr_version = 0;
85 fi->orig_ino = 0;
86 fi->state = 0;
87 mutex_init(&fi->mutex);
88 spin_lock_init(&fi->lock);
89 fi->forget = fuse_alloc_forget();
90 if (!fi->forget) {
91 kmem_cache_free(fuse_inode_cachep, fi);
92 return NULL;
93 }
94
95 return &fi->inode;
96 }
97
98 static void fuse_free_inode(struct inode *inode)
99 {
100 struct fuse_inode *fi = get_fuse_inode(inode);
101
102 mutex_destroy(&fi->mutex);
103 kfree(fi->forget);
104 kmem_cache_free(fuse_inode_cachep, fi);
105 }
106
107 static void fuse_evict_inode(struct inode *inode)
108 {
109 struct fuse_inode *fi = get_fuse_inode(inode);
110
111 truncate_inode_pages_final(&inode->i_data);
112 clear_inode(inode);
113 if (inode->i_sb->s_flags & SB_ACTIVE) {
114 struct fuse_conn *fc = get_fuse_conn(inode);
115 fuse_queue_forget(fc, fi->forget, fi->nodeid, fi->nlookup);
116 fi->forget = NULL;
117 }
118 if (S_ISREG(inode->i_mode) && !is_bad_inode(inode)) {
119 WARN_ON(!list_empty(&fi->write_files));
120 WARN_ON(!list_empty(&fi->queued_writes));
121 }
122 }
123
124 static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
125 {
126 sync_filesystem(sb);
127 if (*flags & SB_MANDLOCK)
128 return -EINVAL;
129
130 return 0;
131 }
132
133
134
135
136
137 static ino_t fuse_squash_ino(u64 ino64)
138 {
139 ino_t ino = (ino_t) ino64;
140 if (sizeof(ino_t) < sizeof(u64))
141 ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8;
142 return ino;
143 }
144
145 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
146 u64 attr_valid)
147 {
148 struct fuse_conn *fc = get_fuse_conn(inode);
149 struct fuse_inode *fi = get_fuse_inode(inode);
150
151 lockdep_assert_held(&fi->lock);
152
153 fi->attr_version = atomic64_inc_return(&fc->attr_version);
154 fi->i_time = attr_valid;
155 WRITE_ONCE(fi->inval_mask, 0);
156
157 inode->i_ino = fuse_squash_ino(attr->ino);
158 inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
159 set_nlink(inode, attr->nlink);
160 inode->i_uid = make_kuid(fc->user_ns, attr->uid);
161 inode->i_gid = make_kgid(fc->user_ns, attr->gid);
162 inode->i_blocks = attr->blocks;
163 inode->i_atime.tv_sec = attr->atime;
164 inode->i_atime.tv_nsec = attr->atimensec;
165
166 if (!fc->writeback_cache || !S_ISREG(inode->i_mode)) {
167 inode->i_mtime.tv_sec = attr->mtime;
168 inode->i_mtime.tv_nsec = attr->mtimensec;
169 inode->i_ctime.tv_sec = attr->ctime;
170 inode->i_ctime.tv_nsec = attr->ctimensec;
171 }
172
173 if (attr->blksize != 0)
174 inode->i_blkbits = ilog2(attr->blksize);
175 else
176 inode->i_blkbits = inode->i_sb->s_blocksize_bits;
177
178
179
180
181
182
183 fi->orig_i_mode = inode->i_mode;
184 if (!fc->default_permissions)
185 inode->i_mode &= ~S_ISVTX;
186
187 fi->orig_ino = attr->ino;
188 }
189
190 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
191 u64 attr_valid, u64 attr_version)
192 {
193 struct fuse_conn *fc = get_fuse_conn(inode);
194 struct fuse_inode *fi = get_fuse_inode(inode);
195 bool is_wb = fc->writeback_cache;
196 loff_t oldsize;
197 struct timespec64 old_mtime;
198
199 spin_lock(&fi->lock);
200 if ((attr_version != 0 && fi->attr_version > attr_version) ||
201 test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) {
202 spin_unlock(&fi->lock);
203 return;
204 }
205
206 old_mtime = inode->i_mtime;
207 fuse_change_attributes_common(inode, attr, attr_valid);
208
209 oldsize = inode->i_size;
210
211
212
213
214
215 if (!is_wb || !S_ISREG(inode->i_mode))
216 i_size_write(inode, attr->size);
217 spin_unlock(&fi->lock);
218
219 if (!is_wb && S_ISREG(inode->i_mode)) {
220 bool inval = false;
221
222 if (oldsize != attr->size) {
223 truncate_pagecache(inode, attr->size);
224 if (!fc->explicit_inval_data)
225 inval = true;
226 } else if (fc->auto_inval_data) {
227 struct timespec64 new_mtime = {
228 .tv_sec = attr->mtime,
229 .tv_nsec = attr->mtimensec,
230 };
231
232
233
234
235
236 if (!timespec64_equal(&old_mtime, &new_mtime))
237 inval = true;
238 }
239
240 if (inval)
241 invalidate_inode_pages2(inode->i_mapping);
242 }
243 }
244
245 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
246 {
247 inode->i_mode = attr->mode & S_IFMT;
248 inode->i_size = attr->size;
249 inode->i_mtime.tv_sec = attr->mtime;
250 inode->i_mtime.tv_nsec = attr->mtimensec;
251 inode->i_ctime.tv_sec = attr->ctime;
252 inode->i_ctime.tv_nsec = attr->ctimensec;
253 if (S_ISREG(inode->i_mode)) {
254 fuse_init_common(inode);
255 fuse_init_file_inode(inode);
256 } else if (S_ISDIR(inode->i_mode))
257 fuse_init_dir(inode);
258 else if (S_ISLNK(inode->i_mode))
259 fuse_init_symlink(inode);
260 else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
261 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
262 fuse_init_common(inode);
263 init_special_inode(inode, inode->i_mode,
264 new_decode_dev(attr->rdev));
265 } else
266 BUG();
267 }
268
269 int fuse_inode_eq(struct inode *inode, void *_nodeidp)
270 {
271 u64 nodeid = *(u64 *) _nodeidp;
272 if (get_node_id(inode) == nodeid)
273 return 1;
274 else
275 return 0;
276 }
277
278 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
279 {
280 u64 nodeid = *(u64 *) _nodeidp;
281 get_fuse_inode(inode)->nodeid = nodeid;
282 return 0;
283 }
284
285 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
286 int generation, struct fuse_attr *attr,
287 u64 attr_valid, u64 attr_version)
288 {
289 struct inode *inode;
290 struct fuse_inode *fi;
291 struct fuse_conn *fc = get_fuse_conn_super(sb);
292
293 retry:
294 inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
295 if (!inode)
296 return NULL;
297
298 if ((inode->i_state & I_NEW)) {
299 inode->i_flags |= S_NOATIME;
300 if (!fc->writeback_cache || !S_ISREG(attr->mode))
301 inode->i_flags |= S_NOCMTIME;
302 inode->i_generation = generation;
303 fuse_init_inode(inode, attr);
304 unlock_new_inode(inode);
305 } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
306
307 make_bad_inode(inode);
308 iput(inode);
309 goto retry;
310 }
311
312 fi = get_fuse_inode(inode);
313 spin_lock(&fi->lock);
314 fi->nlookup++;
315 spin_unlock(&fi->lock);
316 fuse_change_attributes(inode, attr, attr_valid, attr_version);
317
318 return inode;
319 }
320
321 int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
322 loff_t offset, loff_t len)
323 {
324 struct inode *inode;
325 pgoff_t pg_start;
326 pgoff_t pg_end;
327
328 inode = ilookup5(sb, nodeid, fuse_inode_eq, &nodeid);
329 if (!inode)
330 return -ENOENT;
331
332 fuse_invalidate_attr(inode);
333 forget_all_cached_acls(inode);
334 if (offset >= 0) {
335 pg_start = offset >> PAGE_SHIFT;
336 if (len <= 0)
337 pg_end = -1;
338 else
339 pg_end = (offset + len - 1) >> PAGE_SHIFT;
340 invalidate_inode_pages2_range(inode->i_mapping,
341 pg_start, pg_end);
342 }
343 iput(inode);
344 return 0;
345 }
346
347 bool fuse_lock_inode(struct inode *inode)
348 {
349 bool locked = false;
350
351 if (!get_fuse_conn(inode)->parallel_dirops) {
352 mutex_lock(&get_fuse_inode(inode)->mutex);
353 locked = true;
354 }
355
356 return locked;
357 }
358
359 void fuse_unlock_inode(struct inode *inode, bool locked)
360 {
361 if (locked)
362 mutex_unlock(&get_fuse_inode(inode)->mutex);
363 }
364
365 static void fuse_umount_begin(struct super_block *sb)
366 {
367 struct fuse_conn *fc = get_fuse_conn_super(sb);
368
369 if (!fc->no_force_umount)
370 fuse_abort_conn(fc);
371 }
372
373 static void fuse_send_destroy(struct fuse_conn *fc)
374 {
375 if (fc->conn_init) {
376 FUSE_ARGS(args);
377
378 args.opcode = FUSE_DESTROY;
379 args.force = true;
380 args.nocreds = true;
381 fuse_simple_request(fc, &args);
382 }
383 }
384
385 static void fuse_put_super(struct super_block *sb)
386 {
387 struct fuse_conn *fc = get_fuse_conn_super(sb);
388
389 mutex_lock(&fuse_mutex);
390 list_del(&fc->entry);
391 fuse_ctl_remove_conn(fc);
392 mutex_unlock(&fuse_mutex);
393
394 fuse_conn_put(fc);
395 }
396
397 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
398 {
399 stbuf->f_type = FUSE_SUPER_MAGIC;
400 stbuf->f_bsize = attr->bsize;
401 stbuf->f_frsize = attr->frsize;
402 stbuf->f_blocks = attr->blocks;
403 stbuf->f_bfree = attr->bfree;
404 stbuf->f_bavail = attr->bavail;
405 stbuf->f_files = attr->files;
406 stbuf->f_ffree = attr->ffree;
407 stbuf->f_namelen = attr->namelen;
408
409 }
410
411 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
412 {
413 struct super_block *sb = dentry->d_sb;
414 struct fuse_conn *fc = get_fuse_conn_super(sb);
415 FUSE_ARGS(args);
416 struct fuse_statfs_out outarg;
417 int err;
418
419 if (!fuse_allow_current_process(fc)) {
420 buf->f_type = FUSE_SUPER_MAGIC;
421 return 0;
422 }
423
424 memset(&outarg, 0, sizeof(outarg));
425 args.in_numargs = 0;
426 args.opcode = FUSE_STATFS;
427 args.nodeid = get_node_id(d_inode(dentry));
428 args.out_numargs = 1;
429 args.out_args[0].size = sizeof(outarg);
430 args.out_args[0].value = &outarg;
431 err = fuse_simple_request(fc, &args);
432 if (!err)
433 convert_fuse_statfs(buf, &outarg.st);
434 return err;
435 }
436
437 enum {
438 OPT_SOURCE,
439 OPT_SUBTYPE,
440 OPT_FD,
441 OPT_ROOTMODE,
442 OPT_USER_ID,
443 OPT_GROUP_ID,
444 OPT_DEFAULT_PERMISSIONS,
445 OPT_ALLOW_OTHER,
446 OPT_MAX_READ,
447 OPT_BLKSIZE,
448 OPT_ERR
449 };
450
451 static const struct fs_parameter_spec fuse_param_specs[] = {
452 fsparam_string ("source", OPT_SOURCE),
453 fsparam_u32 ("fd", OPT_FD),
454 fsparam_u32oct ("rootmode", OPT_ROOTMODE),
455 fsparam_u32 ("user_id", OPT_USER_ID),
456 fsparam_u32 ("group_id", OPT_GROUP_ID),
457 fsparam_flag ("default_permissions", OPT_DEFAULT_PERMISSIONS),
458 fsparam_flag ("allow_other", OPT_ALLOW_OTHER),
459 fsparam_u32 ("max_read", OPT_MAX_READ),
460 fsparam_u32 ("blksize", OPT_BLKSIZE),
461 fsparam_string ("subtype", OPT_SUBTYPE),
462 {}
463 };
464
465 static const struct fs_parameter_description fuse_fs_parameters = {
466 .name = "fuse",
467 .specs = fuse_param_specs,
468 };
469
470 static int fuse_parse_param(struct fs_context *fc, struct fs_parameter *param)
471 {
472 struct fs_parse_result result;
473 struct fuse_fs_context *ctx = fc->fs_private;
474 int opt;
475
476 opt = fs_parse(fc, &fuse_fs_parameters, param, &result);
477 if (opt < 0)
478 return opt;
479
480 switch (opt) {
481 case OPT_SOURCE:
482 if (fc->source)
483 return invalf(fc, "fuse: Multiple sources specified");
484 fc->source = param->string;
485 param->string = NULL;
486 break;
487
488 case OPT_SUBTYPE:
489 if (ctx->subtype)
490 return invalf(fc, "fuse: Multiple subtypes specified");
491 ctx->subtype = param->string;
492 param->string = NULL;
493 return 0;
494
495 case OPT_FD:
496 ctx->fd = result.uint_32;
497 ctx->fd_present = 1;
498 break;
499
500 case OPT_ROOTMODE:
501 if (!fuse_valid_type(result.uint_32))
502 return invalf(fc, "fuse: Invalid rootmode");
503 ctx->rootmode = result.uint_32;
504 ctx->rootmode_present = 1;
505 break;
506
507 case OPT_USER_ID:
508 ctx->user_id = make_kuid(fc->user_ns, result.uint_32);
509 if (!uid_valid(ctx->user_id))
510 return invalf(fc, "fuse: Invalid user_id");
511 ctx->user_id_present = 1;
512 break;
513
514 case OPT_GROUP_ID:
515 ctx->group_id = make_kgid(fc->user_ns, result.uint_32);
516 if (!gid_valid(ctx->group_id))
517 return invalf(fc, "fuse: Invalid group_id");
518 ctx->group_id_present = 1;
519 break;
520
521 case OPT_DEFAULT_PERMISSIONS:
522 ctx->default_permissions = 1;
523 break;
524
525 case OPT_ALLOW_OTHER:
526 ctx->allow_other = 1;
527 break;
528
529 case OPT_MAX_READ:
530 ctx->max_read = result.uint_32;
531 break;
532
533 case OPT_BLKSIZE:
534 if (!ctx->is_bdev)
535 return invalf(fc, "fuse: blksize only supported for fuseblk");
536 ctx->blksize = result.uint_32;
537 break;
538
539 default:
540 return -EINVAL;
541 }
542
543 return 0;
544 }
545
546 static void fuse_free_fc(struct fs_context *fc)
547 {
548 struct fuse_fs_context *ctx = fc->fs_private;
549
550 if (ctx) {
551 kfree(ctx->subtype);
552 kfree(ctx);
553 }
554 }
555
556 static int fuse_show_options(struct seq_file *m, struct dentry *root)
557 {
558 struct super_block *sb = root->d_sb;
559 struct fuse_conn *fc = get_fuse_conn_super(sb);
560
561 if (fc->no_mount_options)
562 return 0;
563
564 seq_printf(m, ",user_id=%u", from_kuid_munged(fc->user_ns, fc->user_id));
565 seq_printf(m, ",group_id=%u", from_kgid_munged(fc->user_ns, fc->group_id));
566 if (fc->default_permissions)
567 seq_puts(m, ",default_permissions");
568 if (fc->allow_other)
569 seq_puts(m, ",allow_other");
570 if (fc->max_read != ~0)
571 seq_printf(m, ",max_read=%u", fc->max_read);
572 if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
573 seq_printf(m, ",blksize=%lu", sb->s_blocksize);
574 return 0;
575 }
576
577 static void fuse_iqueue_init(struct fuse_iqueue *fiq,
578 const struct fuse_iqueue_ops *ops,
579 void *priv)
580 {
581 memset(fiq, 0, sizeof(struct fuse_iqueue));
582 spin_lock_init(&fiq->lock);
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 fiq->ops = ops;
589 fiq->priv = priv;
590 }
591
592 static void fuse_pqueue_init(struct fuse_pqueue *fpq)
593 {
594 unsigned int i;
595
596 spin_lock_init(&fpq->lock);
597 for (i = 0; i < FUSE_PQ_HASH_SIZE; i++)
598 INIT_LIST_HEAD(&fpq->processing[i]);
599 INIT_LIST_HEAD(&fpq->io);
600 fpq->connected = 1;
601 }
602
603 void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns,
604 const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv)
605 {
606 memset(fc, 0, sizeof(*fc));
607 spin_lock_init(&fc->lock);
608 spin_lock_init(&fc->bg_lock);
609 init_rwsem(&fc->killsb);
610 refcount_set(&fc->count, 1);
611 atomic_set(&fc->dev_count, 1);
612 init_waitqueue_head(&fc->blocked_waitq);
613 fuse_iqueue_init(&fc->iq, fiq_ops, fiq_priv);
614 INIT_LIST_HEAD(&fc->bg_queue);
615 INIT_LIST_HEAD(&fc->entry);
616 INIT_LIST_HEAD(&fc->devices);
617 atomic_set(&fc->num_waiting, 0);
618 fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
619 fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
620 atomic64_set(&fc->khctr, 0);
621 fc->polled_files = RB_ROOT;
622 fc->blocked = 0;
623 fc->initialized = 0;
624 fc->connected = 1;
625 atomic64_set(&fc->attr_version, 1);
626 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
627 fc->pid_ns = get_pid_ns(task_active_pid_ns(current));
628 fc->user_ns = get_user_ns(user_ns);
629 fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ;
630 }
631 EXPORT_SYMBOL_GPL(fuse_conn_init);
632
633 void fuse_conn_put(struct fuse_conn *fc)
634 {
635 if (refcount_dec_and_test(&fc->count)) {
636 struct fuse_iqueue *fiq = &fc->iq;
637
638 if (fiq->ops->release)
639 fiq->ops->release(fiq);
640 put_pid_ns(fc->pid_ns);
641 put_user_ns(fc->user_ns);
642 fc->release(fc);
643 }
644 }
645 EXPORT_SYMBOL_GPL(fuse_conn_put);
646
647 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
648 {
649 refcount_inc(&fc->count);
650 return fc;
651 }
652 EXPORT_SYMBOL_GPL(fuse_conn_get);
653
654 static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
655 {
656 struct fuse_attr attr;
657 memset(&attr, 0, sizeof(attr));
658
659 attr.mode = mode;
660 attr.ino = FUSE_ROOT_ID;
661 attr.nlink = 1;
662 return fuse_iget(sb, 1, 0, &attr, 0, 0);
663 }
664
665 struct fuse_inode_handle {
666 u64 nodeid;
667 u32 generation;
668 };
669
670 static struct dentry *fuse_get_dentry(struct super_block *sb,
671 struct fuse_inode_handle *handle)
672 {
673 struct fuse_conn *fc = get_fuse_conn_super(sb);
674 struct inode *inode;
675 struct dentry *entry;
676 int err = -ESTALE;
677
678 if (handle->nodeid == 0)
679 goto out_err;
680
681 inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
682 if (!inode) {
683 struct fuse_entry_out outarg;
684 const struct qstr name = QSTR_INIT(".", 1);
685
686 if (!fc->export_support)
687 goto out_err;
688
689 err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
690 &inode);
691 if (err && err != -ENOENT)
692 goto out_err;
693 if (err || !inode) {
694 err = -ESTALE;
695 goto out_err;
696 }
697 err = -EIO;
698 if (get_node_id(inode) != handle->nodeid)
699 goto out_iput;
700 }
701 err = -ESTALE;
702 if (inode->i_generation != handle->generation)
703 goto out_iput;
704
705 entry = d_obtain_alias(inode);
706 if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID)
707 fuse_invalidate_entry_cache(entry);
708
709 return entry;
710
711 out_iput:
712 iput(inode);
713 out_err:
714 return ERR_PTR(err);
715 }
716
717 static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len,
718 struct inode *parent)
719 {
720 int len = parent ? 6 : 3;
721 u64 nodeid;
722 u32 generation;
723
724 if (*max_len < len) {
725 *max_len = len;
726 return FILEID_INVALID;
727 }
728
729 nodeid = get_fuse_inode(inode)->nodeid;
730 generation = inode->i_generation;
731
732 fh[0] = (u32)(nodeid >> 32);
733 fh[1] = (u32)(nodeid & 0xffffffff);
734 fh[2] = generation;
735
736 if (parent) {
737 nodeid = get_fuse_inode(parent)->nodeid;
738 generation = parent->i_generation;
739
740 fh[3] = (u32)(nodeid >> 32);
741 fh[4] = (u32)(nodeid & 0xffffffff);
742 fh[5] = generation;
743 }
744
745 *max_len = len;
746 return parent ? 0x82 : 0x81;
747 }
748
749 static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
750 struct fid *fid, int fh_len, int fh_type)
751 {
752 struct fuse_inode_handle handle;
753
754 if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
755 return NULL;
756
757 handle.nodeid = (u64) fid->raw[0] << 32;
758 handle.nodeid |= (u64) fid->raw[1];
759 handle.generation = fid->raw[2];
760 return fuse_get_dentry(sb, &handle);
761 }
762
763 static struct dentry *fuse_fh_to_parent(struct super_block *sb,
764 struct fid *fid, int fh_len, int fh_type)
765 {
766 struct fuse_inode_handle parent;
767
768 if (fh_type != 0x82 || fh_len < 6)
769 return NULL;
770
771 parent.nodeid = (u64) fid->raw[3] << 32;
772 parent.nodeid |= (u64) fid->raw[4];
773 parent.generation = fid->raw[5];
774 return fuse_get_dentry(sb, &parent);
775 }
776
777 static struct dentry *fuse_get_parent(struct dentry *child)
778 {
779 struct inode *child_inode = d_inode(child);
780 struct fuse_conn *fc = get_fuse_conn(child_inode);
781 struct inode *inode;
782 struct dentry *parent;
783 struct fuse_entry_out outarg;
784 const struct qstr name = QSTR_INIT("..", 2);
785 int err;
786
787 if (!fc->export_support)
788 return ERR_PTR(-ESTALE);
789
790 err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
791 &name, &outarg, &inode);
792 if (err) {
793 if (err == -ENOENT)
794 return ERR_PTR(-ESTALE);
795 return ERR_PTR(err);
796 }
797
798 parent = d_obtain_alias(inode);
799 if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID)
800 fuse_invalidate_entry_cache(parent);
801
802 return parent;
803 }
804
805 static const struct export_operations fuse_export_operations = {
806 .fh_to_dentry = fuse_fh_to_dentry,
807 .fh_to_parent = fuse_fh_to_parent,
808 .encode_fh = fuse_encode_fh,
809 .get_parent = fuse_get_parent,
810 };
811
812 static const struct super_operations fuse_super_operations = {
813 .alloc_inode = fuse_alloc_inode,
814 .free_inode = fuse_free_inode,
815 .evict_inode = fuse_evict_inode,
816 .write_inode = fuse_write_inode,
817 .drop_inode = generic_delete_inode,
818 .remount_fs = fuse_remount_fs,
819 .put_super = fuse_put_super,
820 .umount_begin = fuse_umount_begin,
821 .statfs = fuse_statfs,
822 .show_options = fuse_show_options,
823 };
824
825 static void sanitize_global_limit(unsigned *limit)
826 {
827
828
829
830
831 if (*limit == 0)
832 *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 392;
833
834 if (*limit >= 1 << 16)
835 *limit = (1 << 16) - 1;
836 }
837
838 static int set_global_limit(const char *val, const struct kernel_param *kp)
839 {
840 int rv;
841
842 rv = param_set_uint(val, kp);
843 if (rv)
844 return rv;
845
846 sanitize_global_limit((unsigned *)kp->arg);
847
848 return 0;
849 }
850
851 static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg)
852 {
853 int cap_sys_admin = capable(CAP_SYS_ADMIN);
854
855 if (arg->minor < 13)
856 return;
857
858 sanitize_global_limit(&max_user_bgreq);
859 sanitize_global_limit(&max_user_congthresh);
860
861 spin_lock(&fc->bg_lock);
862 if (arg->max_background) {
863 fc->max_background = arg->max_background;
864
865 if (!cap_sys_admin && fc->max_background > max_user_bgreq)
866 fc->max_background = max_user_bgreq;
867 }
868 if (arg->congestion_threshold) {
869 fc->congestion_threshold = arg->congestion_threshold;
870
871 if (!cap_sys_admin &&
872 fc->congestion_threshold > max_user_congthresh)
873 fc->congestion_threshold = max_user_congthresh;
874 }
875 spin_unlock(&fc->bg_lock);
876 }
877
878 struct fuse_init_args {
879 struct fuse_args args;
880 struct fuse_init_in in;
881 struct fuse_init_out out;
882 };
883
884 static void process_init_reply(struct fuse_conn *fc, struct fuse_args *args,
885 int error)
886 {
887 struct fuse_init_args *ia = container_of(args, typeof(*ia), args);
888 struct fuse_init_out *arg = &ia->out;
889
890 if (error || arg->major != FUSE_KERNEL_VERSION)
891 fc->conn_error = 1;
892 else {
893 unsigned long ra_pages;
894
895 process_init_limits(fc, arg);
896
897 if (arg->minor >= 6) {
898 ra_pages = arg->max_readahead / PAGE_SIZE;
899 if (arg->flags & FUSE_ASYNC_READ)
900 fc->async_read = 1;
901 if (!(arg->flags & FUSE_POSIX_LOCKS))
902 fc->no_lock = 1;
903 if (arg->minor >= 17) {
904 if (!(arg->flags & FUSE_FLOCK_LOCKS))
905 fc->no_flock = 1;
906 } else {
907 if (!(arg->flags & FUSE_POSIX_LOCKS))
908 fc->no_flock = 1;
909 }
910 if (arg->flags & FUSE_ATOMIC_O_TRUNC)
911 fc->atomic_o_trunc = 1;
912 if (arg->minor >= 9) {
913
914 if (arg->flags & FUSE_EXPORT_SUPPORT)
915 fc->export_support = 1;
916 }
917 if (arg->flags & FUSE_BIG_WRITES)
918 fc->big_writes = 1;
919 if (arg->flags & FUSE_DONT_MASK)
920 fc->dont_mask = 1;
921 if (arg->flags & FUSE_AUTO_INVAL_DATA)
922 fc->auto_inval_data = 1;
923 else if (arg->flags & FUSE_EXPLICIT_INVAL_DATA)
924 fc->explicit_inval_data = 1;
925 if (arg->flags & FUSE_DO_READDIRPLUS) {
926 fc->do_readdirplus = 1;
927 if (arg->flags & FUSE_READDIRPLUS_AUTO)
928 fc->readdirplus_auto = 1;
929 }
930 if (arg->flags & FUSE_ASYNC_DIO)
931 fc->async_dio = 1;
932 if (arg->flags & FUSE_WRITEBACK_CACHE)
933 fc->writeback_cache = 1;
934 if (arg->flags & FUSE_PARALLEL_DIROPS)
935 fc->parallel_dirops = 1;
936 if (arg->flags & FUSE_HANDLE_KILLPRIV)
937 fc->handle_killpriv = 1;
938 if (arg->time_gran && arg->time_gran <= 1000000000)
939 fc->sb->s_time_gran = arg->time_gran;
940 if ((arg->flags & FUSE_POSIX_ACL)) {
941 fc->default_permissions = 1;
942 fc->posix_acl = 1;
943 fc->sb->s_xattr = fuse_acl_xattr_handlers;
944 }
945 if (arg->flags & FUSE_CACHE_SYMLINKS)
946 fc->cache_symlinks = 1;
947 if (arg->flags & FUSE_ABORT_ERROR)
948 fc->abort_err = 1;
949 if (arg->flags & FUSE_MAX_PAGES) {
950 fc->max_pages =
951 min_t(unsigned int, FUSE_MAX_MAX_PAGES,
952 max_t(unsigned int, arg->max_pages, 1));
953 }
954 } else {
955 ra_pages = fc->max_read / PAGE_SIZE;
956 fc->no_lock = 1;
957 fc->no_flock = 1;
958 }
959
960 fc->sb->s_bdi->ra_pages =
961 min(fc->sb->s_bdi->ra_pages, ra_pages);
962 fc->minor = arg->minor;
963 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
964 fc->max_write = max_t(unsigned, 4096, fc->max_write);
965 fc->conn_init = 1;
966 }
967 kfree(ia);
968
969 fuse_set_initialized(fc);
970 wake_up_all(&fc->blocked_waitq);
971 }
972
973 void fuse_send_init(struct fuse_conn *fc)
974 {
975 struct fuse_init_args *ia;
976
977 ia = kzalloc(sizeof(*ia), GFP_KERNEL | __GFP_NOFAIL);
978
979 ia->in.major = FUSE_KERNEL_VERSION;
980 ia->in.minor = FUSE_KERNEL_MINOR_VERSION;
981 ia->in.max_readahead = fc->sb->s_bdi->ra_pages * PAGE_SIZE;
982 ia->in.flags |=
983 FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
984 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
985 FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
986 FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
987 FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
988 FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT |
989 FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL |
990 FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS |
991 FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA;
992 ia->args.opcode = FUSE_INIT;
993 ia->args.in_numargs = 1;
994 ia->args.in_args[0].size = sizeof(ia->in);
995 ia->args.in_args[0].value = &ia->in;
996 ia->args.out_numargs = 1;
997
998
999
1000 ia->args.out_argvar = 1;
1001 ia->args.out_args[0].size = sizeof(ia->out);
1002 ia->args.out_args[0].value = &ia->out;
1003 ia->args.force = true;
1004 ia->args.nocreds = true;
1005 ia->args.end = process_init_reply;
1006
1007 if (fuse_simple_background(fc, &ia->args, GFP_KERNEL) != 0)
1008 process_init_reply(fc, &ia->args, -ENOTCONN);
1009 }
1010 EXPORT_SYMBOL_GPL(fuse_send_init);
1011
1012 void fuse_free_conn(struct fuse_conn *fc)
1013 {
1014 WARN_ON(!list_empty(&fc->devices));
1015 kfree_rcu(fc, rcu);
1016 }
1017 EXPORT_SYMBOL_GPL(fuse_free_conn);
1018
1019 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
1020 {
1021 int err;
1022 char *suffix = "";
1023
1024 if (sb->s_bdev) {
1025 suffix = "-fuseblk";
1026
1027
1028
1029
1030 bdi_put(sb->s_bdi);
1031 sb->s_bdi = &noop_backing_dev_info;
1032 }
1033 err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev),
1034 MINOR(fc->dev), suffix);
1035 if (err)
1036 return err;
1037
1038 sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
1039
1040 sb->s_bdi->capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054 bdi_set_max_ratio(sb->s_bdi, 1);
1055
1056 return 0;
1057 }
1058
1059 struct fuse_dev *fuse_dev_alloc(void)
1060 {
1061 struct fuse_dev *fud;
1062 struct list_head *pq;
1063
1064 fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL);
1065 if (!fud)
1066 return NULL;
1067
1068 pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL);
1069 if (!pq) {
1070 kfree(fud);
1071 return NULL;
1072 }
1073
1074 fud->pq.processing = pq;
1075 fuse_pqueue_init(&fud->pq);
1076
1077 return fud;
1078 }
1079 EXPORT_SYMBOL_GPL(fuse_dev_alloc);
1080
1081 void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc)
1082 {
1083 fud->fc = fuse_conn_get(fc);
1084 spin_lock(&fc->lock);
1085 list_add_tail(&fud->entry, &fc->devices);
1086 spin_unlock(&fc->lock);
1087 }
1088 EXPORT_SYMBOL_GPL(fuse_dev_install);
1089
1090 struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc)
1091 {
1092 struct fuse_dev *fud;
1093
1094 fud = fuse_dev_alloc();
1095 if (!fud)
1096 return NULL;
1097
1098 fuse_dev_install(fud, fc);
1099 return fud;
1100 }
1101 EXPORT_SYMBOL_GPL(fuse_dev_alloc_install);
1102
1103 void fuse_dev_free(struct fuse_dev *fud)
1104 {
1105 struct fuse_conn *fc = fud->fc;
1106
1107 if (fc) {
1108 spin_lock(&fc->lock);
1109 list_del(&fud->entry);
1110 spin_unlock(&fc->lock);
1111
1112 fuse_conn_put(fc);
1113 }
1114 kfree(fud->pq.processing);
1115 kfree(fud);
1116 }
1117 EXPORT_SYMBOL_GPL(fuse_dev_free);
1118
1119 int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx)
1120 {
1121 struct fuse_dev *fud;
1122 struct fuse_conn *fc = get_fuse_conn_super(sb);
1123 struct inode *root;
1124 struct dentry *root_dentry;
1125 int err;
1126
1127 err = -EINVAL;
1128 if (sb->s_flags & SB_MANDLOCK)
1129 goto err;
1130
1131 sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION);
1132
1133 if (ctx->is_bdev) {
1134 #ifdef CONFIG_BLOCK
1135 err = -EINVAL;
1136 if (!sb_set_blocksize(sb, ctx->blksize))
1137 goto err;
1138 #endif
1139 } else {
1140 sb->s_blocksize = PAGE_SIZE;
1141 sb->s_blocksize_bits = PAGE_SHIFT;
1142 }
1143
1144 sb->s_subtype = ctx->subtype;
1145 ctx->subtype = NULL;
1146 sb->s_magic = FUSE_SUPER_MAGIC;
1147 sb->s_op = &fuse_super_operations;
1148 sb->s_xattr = fuse_xattr_handlers;
1149 sb->s_maxbytes = MAX_LFS_FILESIZE;
1150 sb->s_time_gran = 1;
1151 sb->s_export_op = &fuse_export_operations;
1152 sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE;
1153 if (sb->s_user_ns != &init_user_ns)
1154 sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER;
1155
1156
1157
1158
1159
1160 if (sb->s_user_ns != &init_user_ns)
1161 sb->s_xattr = fuse_no_acl_xattr_handlers;
1162
1163 fud = fuse_dev_alloc_install(fc);
1164 if (!fud)
1165 goto err;
1166
1167 fc->dev = sb->s_dev;
1168 fc->sb = sb;
1169 err = fuse_bdi_init(fc, sb);
1170 if (err)
1171 goto err_dev_free;
1172
1173
1174 if (sb->s_flags & SB_POSIXACL)
1175 fc->dont_mask = 1;
1176 sb->s_flags |= SB_POSIXACL;
1177
1178 fc->default_permissions = ctx->default_permissions;
1179 fc->allow_other = ctx->allow_other;
1180 fc->user_id = ctx->user_id;
1181 fc->group_id = ctx->group_id;
1182 fc->max_read = max_t(unsigned, 4096, ctx->max_read);
1183 fc->destroy = ctx->destroy;
1184 fc->no_control = ctx->no_control;
1185 fc->no_force_umount = ctx->no_force_umount;
1186 fc->no_mount_options = ctx->no_mount_options;
1187
1188 err = -ENOMEM;
1189 root = fuse_get_root_inode(sb, ctx->rootmode);
1190 sb->s_d_op = &fuse_root_dentry_operations;
1191 root_dentry = d_make_root(root);
1192 if (!root_dentry)
1193 goto err_dev_free;
1194
1195 sb->s_d_op = &fuse_dentry_operations;
1196
1197 mutex_lock(&fuse_mutex);
1198 err = -EINVAL;
1199 if (*ctx->fudptr)
1200 goto err_unlock;
1201
1202 err = fuse_ctl_add_conn(fc);
1203 if (err)
1204 goto err_unlock;
1205
1206 list_add_tail(&fc->entry, &fuse_conn_list);
1207 sb->s_root = root_dentry;
1208 *ctx->fudptr = fud;
1209 mutex_unlock(&fuse_mutex);
1210 return 0;
1211
1212 err_unlock:
1213 mutex_unlock(&fuse_mutex);
1214 dput(root_dentry);
1215 err_dev_free:
1216 fuse_dev_free(fud);
1217 err:
1218 return err;
1219 }
1220 EXPORT_SYMBOL_GPL(fuse_fill_super_common);
1221
1222 static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc)
1223 {
1224 struct fuse_fs_context *ctx = fsc->fs_private;
1225 struct file *file;
1226 int err;
1227 struct fuse_conn *fc;
1228
1229 err = -EINVAL;
1230 file = fget(ctx->fd);
1231 if (!file)
1232 goto err;
1233
1234
1235
1236
1237
1238 if ((file->f_op != &fuse_dev_operations) ||
1239 (file->f_cred->user_ns != sb->s_user_ns))
1240 goto err_fput;
1241 ctx->fudptr = &file->private_data;
1242
1243 fc = kmalloc(sizeof(*fc), GFP_KERNEL);
1244 err = -ENOMEM;
1245 if (!fc)
1246 goto err_fput;
1247
1248 fuse_conn_init(fc, sb->s_user_ns, &fuse_dev_fiq_ops, NULL);
1249 fc->release = fuse_free_conn;
1250 sb->s_fs_info = fc;
1251
1252 err = fuse_fill_super_common(sb, ctx);
1253 if (err)
1254 goto err_put_conn;
1255
1256
1257
1258
1259
1260 fput(file);
1261 fuse_send_init(get_fuse_conn_super(sb));
1262 return 0;
1263
1264 err_put_conn:
1265 fuse_conn_put(fc);
1266 sb->s_fs_info = NULL;
1267 err_fput:
1268 fput(file);
1269 err:
1270 return err;
1271 }
1272
1273 static int fuse_get_tree(struct fs_context *fc)
1274 {
1275 struct fuse_fs_context *ctx = fc->fs_private;
1276
1277 if (!ctx->fd_present || !ctx->rootmode_present ||
1278 !ctx->user_id_present || !ctx->group_id_present)
1279 return -EINVAL;
1280
1281 #ifdef CONFIG_BLOCK
1282 if (ctx->is_bdev)
1283 return get_tree_bdev(fc, fuse_fill_super);
1284 #endif
1285
1286 return get_tree_nodev(fc, fuse_fill_super);
1287 }
1288
1289 static const struct fs_context_operations fuse_context_ops = {
1290 .free = fuse_free_fc,
1291 .parse_param = fuse_parse_param,
1292 .get_tree = fuse_get_tree,
1293 };
1294
1295
1296
1297
1298 static int fuse_init_fs_context(struct fs_context *fc)
1299 {
1300 struct fuse_fs_context *ctx;
1301
1302 ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL);
1303 if (!ctx)
1304 return -ENOMEM;
1305
1306 ctx->max_read = ~0;
1307 ctx->blksize = FUSE_DEFAULT_BLKSIZE;
1308
1309 #ifdef CONFIG_BLOCK
1310 if (fc->fs_type == &fuseblk_fs_type) {
1311 ctx->is_bdev = true;
1312 ctx->destroy = true;
1313 }
1314 #endif
1315
1316 fc->fs_private = ctx;
1317 fc->ops = &fuse_context_ops;
1318 return 0;
1319 }
1320
1321 static void fuse_sb_destroy(struct super_block *sb)
1322 {
1323 struct fuse_conn *fc = get_fuse_conn_super(sb);
1324
1325 if (fc) {
1326 if (fc->destroy)
1327 fuse_send_destroy(fc);
1328
1329 fuse_abort_conn(fc);
1330 fuse_wait_aborted(fc);
1331
1332 down_write(&fc->killsb);
1333 fc->sb = NULL;
1334 up_write(&fc->killsb);
1335 }
1336 }
1337
1338 void fuse_kill_sb_anon(struct super_block *sb)
1339 {
1340 fuse_sb_destroy(sb);
1341 kill_anon_super(sb);
1342 }
1343 EXPORT_SYMBOL_GPL(fuse_kill_sb_anon);
1344
1345 static struct file_system_type fuse_fs_type = {
1346 .owner = THIS_MODULE,
1347 .name = "fuse",
1348 .fs_flags = FS_HAS_SUBTYPE | FS_USERNS_MOUNT,
1349 .init_fs_context = fuse_init_fs_context,
1350 .parameters = &fuse_fs_parameters,
1351 .kill_sb = fuse_kill_sb_anon,
1352 };
1353 MODULE_ALIAS_FS("fuse");
1354
1355 #ifdef CONFIG_BLOCK
1356 static void fuse_kill_sb_blk(struct super_block *sb)
1357 {
1358 fuse_sb_destroy(sb);
1359 kill_block_super(sb);
1360 }
1361
1362 static struct file_system_type fuseblk_fs_type = {
1363 .owner = THIS_MODULE,
1364 .name = "fuseblk",
1365 .init_fs_context = fuse_init_fs_context,
1366 .parameters = &fuse_fs_parameters,
1367 .kill_sb = fuse_kill_sb_blk,
1368 .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
1369 };
1370 MODULE_ALIAS_FS("fuseblk");
1371
1372 static inline int register_fuseblk(void)
1373 {
1374 return register_filesystem(&fuseblk_fs_type);
1375 }
1376
1377 static inline void unregister_fuseblk(void)
1378 {
1379 unregister_filesystem(&fuseblk_fs_type);
1380 }
1381 #else
1382 static inline int register_fuseblk(void)
1383 {
1384 return 0;
1385 }
1386
1387 static inline void unregister_fuseblk(void)
1388 {
1389 }
1390 #endif
1391
1392 static void fuse_inode_init_once(void *foo)
1393 {
1394 struct inode *inode = foo;
1395
1396 inode_init_once(inode);
1397 }
1398
1399 static int __init fuse_fs_init(void)
1400 {
1401 int err;
1402
1403 fuse_inode_cachep = kmem_cache_create("fuse_inode",
1404 sizeof(struct fuse_inode), 0,
1405 SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT,
1406 fuse_inode_init_once);
1407 err = -ENOMEM;
1408 if (!fuse_inode_cachep)
1409 goto out;
1410
1411 err = register_fuseblk();
1412 if (err)
1413 goto out2;
1414
1415 err = register_filesystem(&fuse_fs_type);
1416 if (err)
1417 goto out3;
1418
1419 return 0;
1420
1421 out3:
1422 unregister_fuseblk();
1423 out2:
1424 kmem_cache_destroy(fuse_inode_cachep);
1425 out:
1426 return err;
1427 }
1428
1429 static void fuse_fs_cleanup(void)
1430 {
1431 unregister_filesystem(&fuse_fs_type);
1432 unregister_fuseblk();
1433
1434
1435
1436
1437
1438 rcu_barrier();
1439 kmem_cache_destroy(fuse_inode_cachep);
1440 }
1441
1442 static struct kobject *fuse_kobj;
1443
1444 static int fuse_sysfs_init(void)
1445 {
1446 int err;
1447
1448 fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
1449 if (!fuse_kobj) {
1450 err = -ENOMEM;
1451 goto out_err;
1452 }
1453
1454 err = sysfs_create_mount_point(fuse_kobj, "connections");
1455 if (err)
1456 goto out_fuse_unregister;
1457
1458 return 0;
1459
1460 out_fuse_unregister:
1461 kobject_put(fuse_kobj);
1462 out_err:
1463 return err;
1464 }
1465
1466 static void fuse_sysfs_cleanup(void)
1467 {
1468 sysfs_remove_mount_point(fuse_kobj, "connections");
1469 kobject_put(fuse_kobj);
1470 }
1471
1472 static int __init fuse_init(void)
1473 {
1474 int res;
1475
1476 pr_info("init (API version %i.%i)\n",
1477 FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
1478
1479 INIT_LIST_HEAD(&fuse_conn_list);
1480 res = fuse_fs_init();
1481 if (res)
1482 goto err;
1483
1484 res = fuse_dev_init();
1485 if (res)
1486 goto err_fs_cleanup;
1487
1488 res = fuse_sysfs_init();
1489 if (res)
1490 goto err_dev_cleanup;
1491
1492 res = fuse_ctl_init();
1493 if (res)
1494 goto err_sysfs_cleanup;
1495
1496 sanitize_global_limit(&max_user_bgreq);
1497 sanitize_global_limit(&max_user_congthresh);
1498
1499 return 0;
1500
1501 err_sysfs_cleanup:
1502 fuse_sysfs_cleanup();
1503 err_dev_cleanup:
1504 fuse_dev_cleanup();
1505 err_fs_cleanup:
1506 fuse_fs_cleanup();
1507 err:
1508 return res;
1509 }
1510
1511 static void __exit fuse_exit(void)
1512 {
1513 pr_debug("exit\n");
1514
1515 fuse_ctl_cleanup();
1516 fuse_sysfs_cleanup();
1517 fuse_fs_cleanup();
1518 fuse_dev_cleanup();
1519 }
1520
1521 module_init(fuse_init);
1522 module_exit(fuse_exit);