Commit | Line | Data |
---|---|---|
d8a5ba45 MS |
1 | /* |
2 | FUSE: Filesystem in Userspace | |
1729a16c | 3 | Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu> |
d8a5ba45 MS |
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> | |
d8a5ba45 MS |
14 | #include <linux/seq_file.h> |
15 | #include <linux/init.h> | |
16 | #include <linux/module.h> | |
487ea5af | 17 | #include <linux/moduleparam.h> |
c30da2e9 DH |
18 | #include <linux/fs_context.h> |
19 | #include <linux/fs_parser.h> | |
d8a5ba45 | 20 | #include <linux/statfs.h> |
9c8ef561 | 21 | #include <linux/random.h> |
e8edc6e0 | 22 | #include <linux/sched.h> |
dbd561d2 | 23 | #include <linux/exportfs.h> |
60bcc88a | 24 | #include <linux/posix_acl.h> |
0b6e9ea0 | 25 | #include <linux/pid_namespace.h> |
d8a5ba45 MS |
26 | |
27 | MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); | |
28 | MODULE_DESCRIPTION("Filesystem in Userspace"); | |
29 | MODULE_LICENSE("GPL"); | |
30 | ||
e18b890b | 31 | static struct kmem_cache *fuse_inode_cachep; |
bafa9654 MS |
32 | struct list_head fuse_conn_list; |
33 | DEFINE_MUTEX(fuse_mutex); | |
d8a5ba45 | 34 | |
e4dca7b7 | 35 | static int set_global_limit(const char *val, const struct kernel_param *kp); |
487ea5af | 36 | |
79a9d994 | 37 | unsigned max_user_bgreq; |
487ea5af CH |
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 | ||
79a9d994 | 45 | unsigned max_user_congthresh; |
487ea5af CH |
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 | ||
d8a5ba45 MS |
53 | #define FUSE_SUPER_MAGIC 0x65735546 |
54 | ||
d1875dba MS |
55 | #define FUSE_DEFAULT_BLKSIZE 512 |
56 | ||
7a6d3c8b CH |
57 | /** Maximum number of outstanding background requests */ |
58 | #define FUSE_DEFAULT_MAX_BACKGROUND 12 | |
59 | ||
60 | /** Congestion starts at 75% of maximum */ | |
61 | #define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4) | |
62 | ||
c30da2e9 DH |
63 | #ifdef CONFIG_BLOCK |
64 | static struct file_system_type fuseblk_fs_type; | |
65 | #endif | |
66 | ||
a2daff68 | 67 | struct fuse_forget_link *fuse_alloc_forget(void) |
07e77dca | 68 | { |
dc69e98c | 69 | return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL_ACCOUNT); |
07e77dca MS |
70 | } |
71 | ||
d8a5ba45 MS |
72 | static struct inode *fuse_alloc_inode(struct super_block *sb) |
73 | { | |
d8a5ba45 MS |
74 | struct fuse_inode *fi; |
75 | ||
9031a69c | 76 | fi = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL); |
77 | if (!fi) | |
d8a5ba45 MS |
78 | return NULL; |
79 | ||
0a0898cf | 80 | fi->i_time = 0; |
2f1e8196 | 81 | fi->inval_mask = 0; |
d8a5ba45 | 82 | fi->nodeid = 0; |
9e6268db | 83 | fi->nlookup = 0; |
fbee36b9 | 84 | fi->attr_version = 0; |
45c72cd7 | 85 | fi->orig_ino = 0; |
4582a4ab | 86 | fi->state = 0; |
5c672ab3 | 87 | mutex_init(&fi->mutex); |
6ae330ca | 88 | init_rwsem(&fi->i_mmap_sem); |
f15ecfef | 89 | spin_lock_init(&fi->lock); |
07e77dca | 90 | fi->forget = fuse_alloc_forget(); |
c2d0ad00 VG |
91 | if (!fi->forget) |
92 | goto out_free; | |
93 | ||
94 | if (IS_ENABLED(CONFIG_FUSE_DAX) && !fuse_dax_inode_alloc(sb, fi)) | |
95 | goto out_free_forget; | |
d8a5ba45 | 96 | |
9031a69c | 97 | return &fi->inode; |
c2d0ad00 VG |
98 | |
99 | out_free_forget: | |
100 | kfree(fi->forget); | |
101 | out_free: | |
102 | kmem_cache_free(fuse_inode_cachep, fi); | |
103 | return NULL; | |
d8a5ba45 MS |
104 | } |
105 | ||
9baf28bb | 106 | static void fuse_free_inode(struct inode *inode) |
d8a5ba45 | 107 | { |
e5e5558e | 108 | struct fuse_inode *fi = get_fuse_inode(inode); |
9baf28bb | 109 | |
5c672ab3 | 110 | mutex_destroy(&fi->mutex); |
07e77dca | 111 | kfree(fi->forget); |
c2d0ad00 VG |
112 | #ifdef CONFIG_FUSE_DAX |
113 | kfree(fi->dax); | |
114 | #endif | |
9baf28bb | 115 | kmem_cache_free(fuse_inode_cachep, fi); |
d8a5ba45 MS |
116 | } |
117 | ||
b57922d9 | 118 | static void fuse_evict_inode(struct inode *inode) |
d8a5ba45 | 119 | { |
9baf28bb AV |
120 | struct fuse_inode *fi = get_fuse_inode(inode); |
121 | ||
91b0abe3 | 122 | truncate_inode_pages_final(&inode->i_data); |
dbd5768f | 123 | clear_inode(inode); |
1751e8a6 | 124 | if (inode->i_sb->s_flags & SB_ACTIVE) { |
1e9a4ed9 | 125 | struct fuse_conn *fc = get_fuse_conn(inode); |
c2d0ad00 VG |
126 | |
127 | if (FUSE_IS_DAX(inode)) | |
128 | fuse_dax_inode_cleanup(inode); | |
1866d779 MR |
129 | if (fi->nlookup) { |
130 | fuse_queue_forget(fc, fi->forget, fi->nodeid, | |
131 | fi->nlookup); | |
132 | fi->forget = NULL; | |
133 | } | |
e5e5558e | 134 | } |
5d069dbe | 135 | if (S_ISREG(inode->i_mode) && !fuse_is_bad(inode)) { |
9baf28bb AV |
136 | WARN_ON(!list_empty(&fi->write_files)); |
137 | WARN_ON(!list_empty(&fi->queued_writes)); | |
138 | } | |
d8a5ba45 MS |
139 | } |
140 | ||
84c21507 | 141 | static int fuse_reconfigure(struct fs_context *fsc) |
71421259 | 142 | { |
84c21507 | 143 | struct super_block *sb = fsc->root->d_sb; |
0189a2d3 | 144 | |
02b9984d | 145 | sync_filesystem(sb); |
84c21507 | 146 | if (fsc->sb_flags & SB_MANDLOCK) |
71421259 MS |
147 | return -EINVAL; |
148 | ||
149 | return 0; | |
150 | } | |
151 | ||
45c72cd7 PS |
152 | /* |
153 | * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down | |
154 | * so that it will fit. | |
155 | */ | |
156 | static ino_t fuse_squash_ino(u64 ino64) | |
157 | { | |
158 | ino_t ino = (ino_t) ino64; | |
159 | if (sizeof(ino_t) < sizeof(u64)) | |
160 | ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8; | |
161 | return ino; | |
162 | } | |
163 | ||
3be5a52b MS |
164 | void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr, |
165 | u64 attr_valid) | |
d8a5ba45 | 166 | { |
9ffbb916 | 167 | struct fuse_conn *fc = get_fuse_conn(inode); |
ebc14c4d | 168 | struct fuse_inode *fi = get_fuse_inode(inode); |
d8a5ba45 | 169 | |
f15ecfef KT |
170 | lockdep_assert_held(&fi->lock); |
171 | ||
4510d86f | 172 | fi->attr_version = atomic64_inc_return(&fc->attr_version); |
1fb69e78 | 173 | fi->i_time = attr_valid; |
2f1e8196 | 174 | WRITE_ONCE(fi->inval_mask, 0); |
1fb69e78 | 175 | |
45c72cd7 | 176 | inode->i_ino = fuse_squash_ino(attr->ino); |
ebc14c4d | 177 | inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777); |
bfe86848 | 178 | set_nlink(inode, attr->nlink); |
8cb08329 EB |
179 | inode->i_uid = make_kuid(fc->user_ns, attr->uid); |
180 | inode->i_gid = make_kgid(fc->user_ns, attr->gid); | |
d8a5ba45 MS |
181 | inode->i_blocks = attr->blocks; |
182 | inode->i_atime.tv_sec = attr->atime; | |
183 | inode->i_atime.tv_nsec = attr->atimensec; | |
b0aa7606 MP |
184 | /* mtime from server may be stale due to local buffered write */ |
185 | if (!fc->writeback_cache || !S_ISREG(inode->i_mode)) { | |
186 | inode->i_mtime.tv_sec = attr->mtime; | |
187 | inode->i_mtime.tv_nsec = attr->mtimensec; | |
31f3267b MP |
188 | inode->i_ctime.tv_sec = attr->ctime; |
189 | inode->i_ctime.tv_nsec = attr->ctimensec; | |
b0aa7606 | 190 | } |
e00d2c2d | 191 | |
0e9663ee MS |
192 | if (attr->blksize != 0) |
193 | inode->i_blkbits = ilog2(attr->blksize); | |
194 | else | |
195 | inode->i_blkbits = inode->i_sb->s_blocksize_bits; | |
196 | ||
ebc14c4d MS |
197 | /* |
198 | * Don't set the sticky bit in i_mode, unless we want the VFS | |
199 | * to check permissions. This prevents failures due to the | |
200 | * check in may_delete(). | |
201 | */ | |
202 | fi->orig_i_mode = inode->i_mode; | |
29433a29 | 203 | if (!fc->default_permissions) |
ebc14c4d | 204 | inode->i_mode &= ~S_ISVTX; |
45c72cd7 PS |
205 | |
206 | fi->orig_ino = attr->ino; | |
9d769e6a VG |
207 | |
208 | /* | |
209 | * We are refreshing inode data and it is possible that another | |
210 | * client set suid/sgid or security.capability xattr. So clear | |
211 | * S_NOSEC. Ideally, we could have cleared it only if suid/sgid | |
212 | * was set or if security.capability xattr was set. But we don't | |
213 | * know if security.capability has been set or not. So clear it | |
214 | * anyway. Its less efficient but should be safe. | |
215 | */ | |
216 | inode->i_flags &= ~S_NOSEC; | |
3be5a52b MS |
217 | } |
218 | ||
219 | void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr, | |
220 | u64 attr_valid, u64 attr_version) | |
221 | { | |
222 | struct fuse_conn *fc = get_fuse_conn(inode); | |
223 | struct fuse_inode *fi = get_fuse_inode(inode); | |
8373200b | 224 | bool is_wb = fc->writeback_cache; |
3be5a52b | 225 | loff_t oldsize; |
a64ba10f | 226 | struct timespec64 old_mtime; |
3be5a52b | 227 | |
f15ecfef | 228 | spin_lock(&fi->lock); |
06a7c3c2 MP |
229 | if ((attr_version != 0 && fi->attr_version > attr_version) || |
230 | test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) { | |
f15ecfef | 231 | spin_unlock(&fi->lock); |
3be5a52b MS |
232 | return; |
233 | } | |
234 | ||
a64ba10f | 235 | old_mtime = inode->i_mtime; |
3be5a52b | 236 | fuse_change_attributes_common(inode, attr, attr_valid); |
ebc14c4d | 237 | |
e00d2c2d | 238 | oldsize = inode->i_size; |
8373200b PE |
239 | /* |
240 | * In case of writeback_cache enabled, the cached writes beyond EOF | |
241 | * extend local i_size without keeping userspace server in sync. So, | |
242 | * attr->size coming from server can be stale. We cannot trust it. | |
243 | */ | |
244 | if (!is_wb || !S_ISREG(inode->i_mode)) | |
245 | i_size_write(inode, attr->size); | |
f15ecfef | 246 | spin_unlock(&fi->lock); |
e00d2c2d | 247 | |
8373200b | 248 | if (!is_wb && S_ISREG(inode->i_mode)) { |
eed2179e BF |
249 | bool inval = false; |
250 | ||
251 | if (oldsize != attr->size) { | |
7caef267 | 252 | truncate_pagecache(inode, attr->size); |
ad2ba64d KS |
253 | if (!fc->explicit_inval_data) |
254 | inval = true; | |
eed2179e | 255 | } else if (fc->auto_inval_data) { |
a64ba10f | 256 | struct timespec64 new_mtime = { |
eed2179e BF |
257 | .tv_sec = attr->mtime, |
258 | .tv_nsec = attr->mtimensec, | |
259 | }; | |
260 | ||
261 | /* | |
262 | * Auto inval mode also checks and invalidates if mtime | |
263 | * has changed. | |
264 | */ | |
a64ba10f | 265 | if (!timespec64_equal(&old_mtime, &new_mtime)) |
eed2179e BF |
266 | inval = true; |
267 | } | |
268 | ||
269 | if (inval) | |
270 | invalidate_inode_pages2(inode->i_mapping); | |
e00d2c2d | 271 | } |
d8a5ba45 MS |
272 | } |
273 | ||
274 | static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr) | |
275 | { | |
276 | inode->i_mode = attr->mode & S_IFMT; | |
9ffbb916 | 277 | inode->i_size = attr->size; |
b0aa7606 MP |
278 | inode->i_mtime.tv_sec = attr->mtime; |
279 | inode->i_mtime.tv_nsec = attr->mtimensec; | |
31f3267b MP |
280 | inode->i_ctime.tv_sec = attr->ctime; |
281 | inode->i_ctime.tv_nsec = attr->ctimensec; | |
e5e5558e MS |
282 | if (S_ISREG(inode->i_mode)) { |
283 | fuse_init_common(inode); | |
b6aeaded | 284 | fuse_init_file_inode(inode); |
e5e5558e MS |
285 | } else if (S_ISDIR(inode->i_mode)) |
286 | fuse_init_dir(inode); | |
287 | else if (S_ISLNK(inode->i_mode)) | |
288 | fuse_init_symlink(inode); | |
289 | else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || | |
290 | S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { | |
291 | fuse_init_common(inode); | |
292 | init_special_inode(inode, inode->i_mode, | |
293 | new_decode_dev(attr->rdev)); | |
39ee059a MS |
294 | } else |
295 | BUG(); | |
d8a5ba45 MS |
296 | } |
297 | ||
fcee216b | 298 | static int fuse_inode_eq(struct inode *inode, void *_nodeidp) |
d8a5ba45 | 299 | { |
b48badf0 | 300 | u64 nodeid = *(u64 *) _nodeidp; |
d8a5ba45 MS |
301 | if (get_node_id(inode) == nodeid) |
302 | return 1; | |
303 | else | |
304 | return 0; | |
305 | } | |
306 | ||
307 | static int fuse_inode_set(struct inode *inode, void *_nodeidp) | |
308 | { | |
b48badf0 | 309 | u64 nodeid = *(u64 *) _nodeidp; |
d8a5ba45 MS |
310 | get_fuse_inode(inode)->nodeid = nodeid; |
311 | return 0; | |
312 | } | |
313 | ||
b48badf0 | 314 | struct inode *fuse_iget(struct super_block *sb, u64 nodeid, |
1fb69e78 MS |
315 | int generation, struct fuse_attr *attr, |
316 | u64 attr_valid, u64 attr_version) | |
d8a5ba45 MS |
317 | { |
318 | struct inode *inode; | |
9e6268db | 319 | struct fuse_inode *fi; |
d8a5ba45 | 320 | struct fuse_conn *fc = get_fuse_conn_super(sb); |
d8a5ba45 | 321 | |
bf109c64 MR |
322 | /* |
323 | * Auto mount points get their node id from the submount root, which is | |
324 | * not a unique identifier within this filesystem. | |
325 | * | |
326 | * To avoid conflicts, do not place submount points into the inode hash | |
327 | * table. | |
328 | */ | |
329 | if (fc->auto_submounts && (attr->flags & FUSE_ATTR_SUBMOUNT) && | |
330 | S_ISDIR(attr->mode)) { | |
331 | inode = new_inode(sb); | |
332 | if (!inode) | |
333 | return NULL; | |
334 | ||
335 | fuse_init_inode(inode, attr); | |
336 | get_fuse_inode(inode)->nodeid = nodeid; | |
337 | inode->i_flags |= S_AUTOMOUNT; | |
338 | goto done; | |
339 | } | |
340 | ||
341 | retry: | |
d8a5ba45 MS |
342 | inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid); |
343 | if (!inode) | |
344 | return NULL; | |
345 | ||
346 | if ((inode->i_state & I_NEW)) { | |
b0aa7606 | 347 | inode->i_flags |= S_NOATIME; |
d31433c8 | 348 | if (!fc->writeback_cache || !S_ISREG(attr->mode)) |
b0aa7606 | 349 | inode->i_flags |= S_NOCMTIME; |
d8a5ba45 | 350 | inode->i_generation = generation; |
d8a5ba45 MS |
351 | fuse_init_inode(inode, attr); |
352 | unlock_new_inode(inode); | |
15db1683 AG |
353 | } else if (fuse_stale_inode(inode, generation, attr)) { |
354 | /* nodeid was reused, any I/O on the old inode should fail */ | |
5d069dbe | 355 | fuse_make_bad(inode); |
d8a5ba45 | 356 | iput(inode); |
d8a5ba45 MS |
357 | goto retry; |
358 | } | |
bf109c64 | 359 | done: |
9e6268db | 360 | fi = get_fuse_inode(inode); |
c9d8f5f0 | 361 | spin_lock(&fi->lock); |
1729a16c | 362 | fi->nlookup++; |
c9d8f5f0 | 363 | spin_unlock(&fi->lock); |
1fb69e78 MS |
364 | fuse_change_attributes(inode, attr, attr_valid, attr_version); |
365 | ||
d8a5ba45 MS |
366 | return inode; |
367 | } | |
368 | ||
fcee216b MR |
369 | struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid, |
370 | struct fuse_mount **fm) | |
371 | { | |
372 | struct fuse_mount *fm_iter; | |
373 | struct inode *inode; | |
374 | ||
375 | WARN_ON(!rwsem_is_locked(&fc->killsb)); | |
376 | list_for_each_entry(fm_iter, &fc->mounts, fc_entry) { | |
377 | if (!fm_iter->sb) | |
378 | continue; | |
379 | ||
380 | inode = ilookup5(fm_iter->sb, nodeid, fuse_inode_eq, &nodeid); | |
381 | if (inode) { | |
382 | if (fm) | |
383 | *fm = fm_iter; | |
384 | return inode; | |
385 | } | |
386 | } | |
387 | ||
388 | return NULL; | |
389 | } | |
390 | ||
391 | int fuse_reverse_inval_inode(struct fuse_conn *fc, u64 nodeid, | |
3b463ae0 JM |
392 | loff_t offset, loff_t len) |
393 | { | |
5ddd9ced | 394 | struct fuse_inode *fi; |
3b463ae0 JM |
395 | struct inode *inode; |
396 | pgoff_t pg_start; | |
397 | pgoff_t pg_end; | |
398 | ||
fcee216b | 399 | inode = fuse_ilookup(fc, nodeid, NULL); |
3b463ae0 JM |
400 | if (!inode) |
401 | return -ENOENT; | |
402 | ||
5ddd9ced MS |
403 | fi = get_fuse_inode(inode); |
404 | spin_lock(&fi->lock); | |
405 | fi->attr_version = atomic64_inc_return(&fc->attr_version); | |
406 | spin_unlock(&fi->lock); | |
407 | ||
3b463ae0 | 408 | fuse_invalidate_attr(inode); |
60bcc88a | 409 | forget_all_cached_acls(inode); |
3b463ae0 | 410 | if (offset >= 0) { |
09cbfeaf | 411 | pg_start = offset >> PAGE_SHIFT; |
3b463ae0 JM |
412 | if (len <= 0) |
413 | pg_end = -1; | |
414 | else | |
09cbfeaf | 415 | pg_end = (offset + len - 1) >> PAGE_SHIFT; |
3b463ae0 JM |
416 | invalidate_inode_pages2_range(inode->i_mapping, |
417 | pg_start, pg_end); | |
418 | } | |
419 | iput(inode); | |
420 | return 0; | |
421 | } | |
422 | ||
63576c13 | 423 | bool fuse_lock_inode(struct inode *inode) |
5c672ab3 | 424 | { |
63576c13 MS |
425 | bool locked = false; |
426 | ||
427 | if (!get_fuse_conn(inode)->parallel_dirops) { | |
5c672ab3 | 428 | mutex_lock(&get_fuse_inode(inode)->mutex); |
63576c13 MS |
429 | locked = true; |
430 | } | |
431 | ||
432 | return locked; | |
5c672ab3 MS |
433 | } |
434 | ||
63576c13 | 435 | void fuse_unlock_inode(struct inode *inode, bool locked) |
5c672ab3 | 436 | { |
63576c13 | 437 | if (locked) |
5c672ab3 MS |
438 | mutex_unlock(&get_fuse_inode(inode)->mutex); |
439 | } | |
440 | ||
42faad99 | 441 | static void fuse_umount_begin(struct super_block *sb) |
69a53bf2 | 442 | { |
15c8e72e VG |
443 | struct fuse_conn *fc = get_fuse_conn_super(sb); |
444 | ||
445 | if (!fc->no_force_umount) | |
446 | fuse_abort_conn(fc); | |
69a53bf2 MS |
447 | } |
448 | ||
fcee216b | 449 | static void fuse_send_destroy(struct fuse_mount *fm) |
0ec7ca41 | 450 | { |
fcee216b | 451 | if (fm->fc->conn_init) { |
1ccd1ea2 MS |
452 | FUSE_ARGS(args); |
453 | ||
454 | args.opcode = FUSE_DESTROY; | |
455 | args.force = true; | |
456 | args.nocreds = true; | |
fcee216b | 457 | fuse_simple_request(fm, &args); |
0ec7ca41 MS |
458 | } |
459 | } | |
460 | ||
a325f9b9 TH |
461 | static void fuse_put_super(struct super_block *sb) |
462 | { | |
fcee216b | 463 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
a325f9b9 | 464 | |
514b5e3f MS |
465 | fuse_conn_put(fm->fc); |
466 | kfree(fm); | |
d8a5ba45 MS |
467 | } |
468 | ||
e5e5558e MS |
469 | static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr) |
470 | { | |
471 | stbuf->f_type = FUSE_SUPER_MAGIC; | |
472 | stbuf->f_bsize = attr->bsize; | |
de5f1202 | 473 | stbuf->f_frsize = attr->frsize; |
e5e5558e MS |
474 | stbuf->f_blocks = attr->blocks; |
475 | stbuf->f_bfree = attr->bfree; | |
476 | stbuf->f_bavail = attr->bavail; | |
477 | stbuf->f_files = attr->files; | |
478 | stbuf->f_ffree = attr->ffree; | |
479 | stbuf->f_namelen = attr->namelen; | |
480 | /* fsid is left zero */ | |
481 | } | |
482 | ||
726c3342 | 483 | static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf) |
e5e5558e | 484 | { |
726c3342 | 485 | struct super_block *sb = dentry->d_sb; |
fcee216b | 486 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
7078187a | 487 | FUSE_ARGS(args); |
e5e5558e MS |
488 | struct fuse_statfs_out outarg; |
489 | int err; | |
490 | ||
fcee216b | 491 | if (!fuse_allow_current_process(fm->fc)) { |
e57ac683 MS |
492 | buf->f_type = FUSE_SUPER_MAGIC; |
493 | return 0; | |
494 | } | |
495 | ||
de5f1202 | 496 | memset(&outarg, 0, sizeof(outarg)); |
d5b48543 MS |
497 | args.in_numargs = 0; |
498 | args.opcode = FUSE_STATFS; | |
499 | args.nodeid = get_node_id(d_inode(dentry)); | |
500 | args.out_numargs = 1; | |
501 | args.out_args[0].size = sizeof(outarg); | |
502 | args.out_args[0].value = &outarg; | |
fcee216b | 503 | err = fuse_simple_request(fm, &args); |
e5e5558e MS |
504 | if (!err) |
505 | convert_fuse_statfs(buf, &outarg.st); | |
e5e5558e MS |
506 | return err; |
507 | } | |
508 | ||
2d82ab25 GK |
509 | static int fuse_sync_fs(struct super_block *sb, int wait) |
510 | { | |
511 | struct fuse_mount *fm = get_fuse_mount_super(sb); | |
512 | struct fuse_conn *fc = fm->fc; | |
513 | struct fuse_syncfs_in inarg; | |
514 | FUSE_ARGS(args); | |
515 | int err; | |
516 | ||
517 | /* | |
518 | * Userspace cannot handle the wait == 0 case. Avoid a | |
519 | * gratuitous roundtrip. | |
520 | */ | |
521 | if (!wait) | |
522 | return 0; | |
523 | ||
524 | /* The filesystem is being unmounted. Nothing to do. */ | |
525 | if (!sb->s_root) | |
526 | return 0; | |
527 | ||
528 | if (!fc->sync_fs) | |
529 | return 0; | |
530 | ||
531 | memset(&inarg, 0, sizeof(inarg)); | |
532 | args.in_numargs = 1; | |
533 | args.in_args[0].size = sizeof(inarg); | |
534 | args.in_args[0].value = &inarg; | |
535 | args.opcode = FUSE_SYNCFS; | |
536 | args.nodeid = get_node_id(sb->s_root->d_inode); | |
537 | args.out_numargs = 0; | |
538 | ||
539 | err = fuse_simple_request(fm, &args); | |
540 | if (err == -ENOSYS) { | |
541 | fc->sync_fs = 0; | |
542 | err = 0; | |
543 | } | |
544 | ||
545 | return err; | |
546 | } | |
547 | ||
d8a5ba45 | 548 | enum { |
c30da2e9 DH |
549 | OPT_SOURCE, |
550 | OPT_SUBTYPE, | |
d8a5ba45 MS |
551 | OPT_FD, |
552 | OPT_ROOTMODE, | |
553 | OPT_USER_ID, | |
87729a55 | 554 | OPT_GROUP_ID, |
d8a5ba45 MS |
555 | OPT_DEFAULT_PERMISSIONS, |
556 | OPT_ALLOW_OTHER, | |
db50b96c | 557 | OPT_MAX_READ, |
d8091614 | 558 | OPT_BLKSIZE, |
d8a5ba45 MS |
559 | OPT_ERR |
560 | }; | |
561 | ||
d7167b14 | 562 | static const struct fs_parameter_spec fuse_fs_parameters[] = { |
c30da2e9 DH |
563 | fsparam_string ("source", OPT_SOURCE), |
564 | fsparam_u32 ("fd", OPT_FD), | |
565 | fsparam_u32oct ("rootmode", OPT_ROOTMODE), | |
566 | fsparam_u32 ("user_id", OPT_USER_ID), | |
567 | fsparam_u32 ("group_id", OPT_GROUP_ID), | |
568 | fsparam_flag ("default_permissions", OPT_DEFAULT_PERMISSIONS), | |
569 | fsparam_flag ("allow_other", OPT_ALLOW_OTHER), | |
570 | fsparam_u32 ("max_read", OPT_MAX_READ), | |
571 | fsparam_u32 ("blksize", OPT_BLKSIZE), | |
c7eb6869 | 572 | fsparam_string ("subtype", OPT_SUBTYPE), |
c30da2e9 DH |
573 | {} |
574 | }; | |
575 | ||
84c21507 | 576 | static int fuse_parse_param(struct fs_context *fsc, struct fs_parameter *param) |
233a01fa | 577 | { |
c30da2e9 | 578 | struct fs_parse_result result; |
84c21507 | 579 | struct fuse_fs_context *ctx = fsc->fs_private; |
c30da2e9 DH |
580 | int opt; |
581 | ||
84c21507 | 582 | if (fsc->purpose == FS_CONTEXT_FOR_RECONFIGURE) { |
b330966f MS |
583 | /* |
584 | * Ignore options coming from mount(MS_REMOUNT) for backward | |
585 | * compatibility. | |
586 | */ | |
84c21507 | 587 | if (fsc->oldapi) |
b330966f MS |
588 | return 0; |
589 | ||
84c21507 | 590 | return invalfc(fsc, "No changes allowed in reconfigure"); |
b330966f | 591 | } |
e8b20a47 | 592 | |
84c21507 | 593 | opt = fs_parse(fsc, fuse_fs_parameters, param, &result); |
c30da2e9 DH |
594 | if (opt < 0) |
595 | return opt; | |
596 | ||
597 | switch (opt) { | |
598 | case OPT_SOURCE: | |
84c21507 MS |
599 | if (fsc->source) |
600 | return invalfc(fsc, "Multiple sources specified"); | |
601 | fsc->source = param->string; | |
c30da2e9 DH |
602 | param->string = NULL; |
603 | break; | |
604 | ||
605 | case OPT_SUBTYPE: | |
606 | if (ctx->subtype) | |
84c21507 | 607 | return invalfc(fsc, "Multiple subtypes specified"); |
c30da2e9 DH |
608 | ctx->subtype = param->string; |
609 | param->string = NULL; | |
610 | return 0; | |
611 | ||
612 | case OPT_FD: | |
613 | ctx->fd = result.uint_32; | |
cabdb4fa | 614 | ctx->fd_present = true; |
c30da2e9 DH |
615 | break; |
616 | ||
617 | case OPT_ROOTMODE: | |
618 | if (!fuse_valid_type(result.uint_32)) | |
84c21507 | 619 | return invalfc(fsc, "Invalid rootmode"); |
c30da2e9 | 620 | ctx->rootmode = result.uint_32; |
cabdb4fa | 621 | ctx->rootmode_present = true; |
c30da2e9 DH |
622 | break; |
623 | ||
624 | case OPT_USER_ID: | |
84c21507 | 625 | ctx->user_id = make_kuid(fsc->user_ns, result.uint_32); |
c30da2e9 | 626 | if (!uid_valid(ctx->user_id)) |
84c21507 | 627 | return invalfc(fsc, "Invalid user_id"); |
cabdb4fa | 628 | ctx->user_id_present = true; |
c30da2e9 DH |
629 | break; |
630 | ||
631 | case OPT_GROUP_ID: | |
84c21507 | 632 | ctx->group_id = make_kgid(fsc->user_ns, result.uint_32); |
c30da2e9 | 633 | if (!gid_valid(ctx->group_id)) |
84c21507 | 634 | return invalfc(fsc, "Invalid group_id"); |
cabdb4fa | 635 | ctx->group_id_present = true; |
c30da2e9 DH |
636 | break; |
637 | ||
638 | case OPT_DEFAULT_PERMISSIONS: | |
cabdb4fa | 639 | ctx->default_permissions = true; |
c30da2e9 DH |
640 | break; |
641 | ||
642 | case OPT_ALLOW_OTHER: | |
cabdb4fa | 643 | ctx->allow_other = true; |
c30da2e9 DH |
644 | break; |
645 | ||
646 | case OPT_MAX_READ: | |
647 | ctx->max_read = result.uint_32; | |
648 | break; | |
649 | ||
650 | case OPT_BLKSIZE: | |
651 | if (!ctx->is_bdev) | |
84c21507 | 652 | return invalfc(fsc, "blksize only supported for fuseblk"); |
c30da2e9 DH |
653 | ctx->blksize = result.uint_32; |
654 | break; | |
655 | ||
656 | default: | |
657 | return -EINVAL; | |
233a01fa | 658 | } |
c30da2e9 DH |
659 | |
660 | return 0; | |
233a01fa MS |
661 | } |
662 | ||
84c21507 | 663 | static void fuse_free_fsc(struct fs_context *fsc) |
d8a5ba45 | 664 | { |
84c21507 | 665 | struct fuse_fs_context *ctx = fsc->fs_private; |
5a533682 | 666 | |
c30da2e9 DH |
667 | if (ctx) { |
668 | kfree(ctx->subtype); | |
669 | kfree(ctx); | |
670 | } | |
d8a5ba45 MS |
671 | } |
672 | ||
34c80b1d | 673 | static int fuse_show_options(struct seq_file *m, struct dentry *root) |
d8a5ba45 | 674 | { |
34c80b1d AV |
675 | struct super_block *sb = root->d_sb; |
676 | struct fuse_conn *fc = get_fuse_conn_super(sb); | |
d8a5ba45 | 677 | |
f4fd4ae3 VG |
678 | if (fc->legacy_opts_show) { |
679 | seq_printf(m, ",user_id=%u", | |
680 | from_kuid_munged(fc->user_ns, fc->user_id)); | |
681 | seq_printf(m, ",group_id=%u", | |
682 | from_kgid_munged(fc->user_ns, fc->group_id)); | |
683 | if (fc->default_permissions) | |
684 | seq_puts(m, ",default_permissions"); | |
685 | if (fc->allow_other) | |
686 | seq_puts(m, ",allow_other"); | |
687 | if (fc->max_read != ~0) | |
688 | seq_printf(m, ",max_read=%u", fc->max_read); | |
689 | if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE) | |
690 | seq_printf(m, ",blksize=%lu", sb->s_blocksize); | |
691 | } | |
1dd53957 VG |
692 | #ifdef CONFIG_FUSE_DAX |
693 | if (fc->dax) | |
694 | seq_puts(m, ",dax"); | |
695 | #endif | |
3f22c746 | 696 | |
d8a5ba45 MS |
697 | return 0; |
698 | } | |
699 | ||
ae3aad77 SH |
700 | static void fuse_iqueue_init(struct fuse_iqueue *fiq, |
701 | const struct fuse_iqueue_ops *ops, | |
702 | void *priv) | |
f88996a9 MS |
703 | { |
704 | memset(fiq, 0, sizeof(struct fuse_iqueue)); | |
76e43c8c | 705 | spin_lock_init(&fiq->lock); |
f88996a9 MS |
706 | init_waitqueue_head(&fiq->waitq); |
707 | INIT_LIST_HEAD(&fiq->pending); | |
708 | INIT_LIST_HEAD(&fiq->interrupts); | |
709 | fiq->forget_list_tail = &fiq->forget_list_head; | |
e16714d8 | 710 | fiq->connected = 1; |
ae3aad77 SH |
711 | fiq->ops = ops; |
712 | fiq->priv = priv; | |
f88996a9 MS |
713 | } |
714 | ||
3a2b5b9c MS |
715 | static void fuse_pqueue_init(struct fuse_pqueue *fpq) |
716 | { | |
be2ff42c KT |
717 | unsigned int i; |
718 | ||
45a91cb1 | 719 | spin_lock_init(&fpq->lock); |
be2ff42c KT |
720 | for (i = 0; i < FUSE_PQ_HASH_SIZE; i++) |
721 | INIT_LIST_HEAD(&fpq->processing[i]); | |
3a2b5b9c | 722 | INIT_LIST_HEAD(&fpq->io); |
e96edd94 | 723 | fpq->connected = 1; |
3a2b5b9c MS |
724 | } |
725 | ||
fcee216b MR |
726 | void fuse_conn_init(struct fuse_conn *fc, struct fuse_mount *fm, |
727 | struct user_namespace *user_ns, | |
ae3aad77 | 728 | const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv) |
d8a5ba45 | 729 | { |
0d179aa5 TH |
730 | memset(fc, 0, sizeof(*fc)); |
731 | spin_lock_init(&fc->lock); | |
ae2dffa3 | 732 | spin_lock_init(&fc->bg_lock); |
3b463ae0 | 733 | init_rwsem(&fc->killsb); |
095fc40a | 734 | refcount_set(&fc->count, 1); |
c3696046 | 735 | atomic_set(&fc->dev_count, 1); |
0d179aa5 | 736 | init_waitqueue_head(&fc->blocked_waitq); |
ae3aad77 | 737 | fuse_iqueue_init(&fc->iq, fiq_ops, fiq_priv); |
0d179aa5 TH |
738 | INIT_LIST_HEAD(&fc->bg_queue); |
739 | INIT_LIST_HEAD(&fc->entry); | |
cc080e9e | 740 | INIT_LIST_HEAD(&fc->devices); |
0d179aa5 | 741 | atomic_set(&fc->num_waiting, 0); |
7a6d3c8b CH |
742 | fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND; |
743 | fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD; | |
75126f55 | 744 | atomic64_set(&fc->khctr, 0); |
0d179aa5 | 745 | fc->polled_files = RB_ROOT; |
0aada884 | 746 | fc->blocked = 0; |
796523fb | 747 | fc->initialized = 0; |
e16714d8 | 748 | fc->connected = 1; |
4510d86f | 749 | atomic64_set(&fc->attr_version, 1); |
0d179aa5 | 750 | get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key)); |
0b6e9ea0 | 751 | fc->pid_ns = get_pid_ns(task_active_pid_ns(current)); |
8cb08329 | 752 | fc->user_ns = get_user_ns(user_ns); |
8a3177db | 753 | fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ; |
a7f0d7aa | 754 | fc->max_pages_limit = FUSE_MAX_MAX_PAGES; |
fcee216b MR |
755 | |
756 | INIT_LIST_HEAD(&fc->mounts); | |
757 | list_add(&fm->fc_entry, &fc->mounts); | |
758 | fm->fc = fc; | |
d8a5ba45 | 759 | } |
0d179aa5 | 760 | EXPORT_SYMBOL_GPL(fuse_conn_init); |
d8a5ba45 | 761 | |
bafa9654 MS |
762 | void fuse_conn_put(struct fuse_conn *fc) |
763 | { | |
095fc40a | 764 | if (refcount_dec_and_test(&fc->count)) { |
a62a8ef9 SH |
765 | struct fuse_iqueue *fiq = &fc->iq; |
766 | ||
1dd53957 VG |
767 | if (IS_ENABLED(CONFIG_FUSE_DAX)) |
768 | fuse_dax_conn_free(fc); | |
a62a8ef9 SH |
769 | if (fiq->ops->release) |
770 | fiq->ops->release(fiq); | |
0b6e9ea0 | 771 | put_pid_ns(fc->pid_ns); |
8cb08329 | 772 | put_user_ns(fc->user_ns); |
43901aab | 773 | fc->release(fc); |
d2a85164 | 774 | } |
bafa9654 | 775 | } |
08cbf542 | 776 | EXPORT_SYMBOL_GPL(fuse_conn_put); |
bafa9654 MS |
777 | |
778 | struct fuse_conn *fuse_conn_get(struct fuse_conn *fc) | |
779 | { | |
095fc40a | 780 | refcount_inc(&fc->count); |
bafa9654 MS |
781 | return fc; |
782 | } | |
08cbf542 | 783 | EXPORT_SYMBOL_GPL(fuse_conn_get); |
bafa9654 | 784 | |
b93f858a | 785 | static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode) |
d8a5ba45 MS |
786 | { |
787 | struct fuse_attr attr; | |
788 | memset(&attr, 0, sizeof(attr)); | |
789 | ||
790 | attr.mode = mode; | |
791 | attr.ino = FUSE_ROOT_ID; | |
074406fa | 792 | attr.nlink = 1; |
1fb69e78 | 793 | return fuse_iget(sb, 1, 0, &attr, 0, 0); |
d8a5ba45 MS |
794 | } |
795 | ||
1729a16c | 796 | struct fuse_inode_handle { |
dbd561d2 MS |
797 | u64 nodeid; |
798 | u32 generation; | |
799 | }; | |
800 | ||
801 | static struct dentry *fuse_get_dentry(struct super_block *sb, | |
802 | struct fuse_inode_handle *handle) | |
803 | { | |
33670fa2 | 804 | struct fuse_conn *fc = get_fuse_conn_super(sb); |
dbd561d2 MS |
805 | struct inode *inode; |
806 | struct dentry *entry; | |
807 | int err = -ESTALE; | |
808 | ||
809 | if (handle->nodeid == 0) | |
810 | goto out_err; | |
811 | ||
812 | inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid); | |
33670fa2 MS |
813 | if (!inode) { |
814 | struct fuse_entry_out outarg; | |
13983d06 | 815 | const struct qstr name = QSTR_INIT(".", 1); |
33670fa2 MS |
816 | |
817 | if (!fc->export_support) | |
818 | goto out_err; | |
819 | ||
33670fa2 MS |
820 | err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg, |
821 | &inode); | |
822 | if (err && err != -ENOENT) | |
823 | goto out_err; | |
824 | if (err || !inode) { | |
825 | err = -ESTALE; | |
826 | goto out_err; | |
827 | } | |
828 | err = -EIO; | |
829 | if (get_node_id(inode) != handle->nodeid) | |
830 | goto out_iput; | |
831 | } | |
dbd561d2 MS |
832 | err = -ESTALE; |
833 | if (inode->i_generation != handle->generation) | |
834 | goto out_iput; | |
835 | ||
44003728 | 836 | entry = d_obtain_alias(inode); |
c35eebe9 | 837 | if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID) |
dbd561d2 | 838 | fuse_invalidate_entry_cache(entry); |
dbd561d2 MS |
839 | |
840 | return entry; | |
841 | ||
842 | out_iput: | |
843 | iput(inode); | |
844 | out_err: | |
845 | return ERR_PTR(err); | |
846 | } | |
847 | ||
b0b0382b AV |
848 | static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len, |
849 | struct inode *parent) | |
dbd561d2 | 850 | { |
b0b0382b | 851 | int len = parent ? 6 : 3; |
dbd561d2 MS |
852 | u64 nodeid; |
853 | u32 generation; | |
854 | ||
5fe0c237 AK |
855 | if (*max_len < len) { |
856 | *max_len = len; | |
94e07a75 | 857 | return FILEID_INVALID; |
5fe0c237 | 858 | } |
dbd561d2 MS |
859 | |
860 | nodeid = get_fuse_inode(inode)->nodeid; | |
861 | generation = inode->i_generation; | |
862 | ||
863 | fh[0] = (u32)(nodeid >> 32); | |
864 | fh[1] = (u32)(nodeid & 0xffffffff); | |
865 | fh[2] = generation; | |
866 | ||
b0b0382b | 867 | if (parent) { |
dbd561d2 MS |
868 | nodeid = get_fuse_inode(parent)->nodeid; |
869 | generation = parent->i_generation; | |
dbd561d2 MS |
870 | |
871 | fh[3] = (u32)(nodeid >> 32); | |
872 | fh[4] = (u32)(nodeid & 0xffffffff); | |
873 | fh[5] = generation; | |
874 | } | |
875 | ||
876 | *max_len = len; | |
b0b0382b | 877 | return parent ? 0x82 : 0x81; |
dbd561d2 MS |
878 | } |
879 | ||
880 | static struct dentry *fuse_fh_to_dentry(struct super_block *sb, | |
881 | struct fid *fid, int fh_len, int fh_type) | |
882 | { | |
883 | struct fuse_inode_handle handle; | |
884 | ||
885 | if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3) | |
886 | return NULL; | |
887 | ||
888 | handle.nodeid = (u64) fid->raw[0] << 32; | |
889 | handle.nodeid |= (u64) fid->raw[1]; | |
890 | handle.generation = fid->raw[2]; | |
891 | return fuse_get_dentry(sb, &handle); | |
892 | } | |
893 | ||
894 | static struct dentry *fuse_fh_to_parent(struct super_block *sb, | |
895 | struct fid *fid, int fh_len, int fh_type) | |
896 | { | |
897 | struct fuse_inode_handle parent; | |
898 | ||
899 | if (fh_type != 0x82 || fh_len < 6) | |
900 | return NULL; | |
901 | ||
902 | parent.nodeid = (u64) fid->raw[3] << 32; | |
903 | parent.nodeid |= (u64) fid->raw[4]; | |
904 | parent.generation = fid->raw[5]; | |
905 | return fuse_get_dentry(sb, &parent); | |
906 | } | |
907 | ||
33670fa2 MS |
908 | static struct dentry *fuse_get_parent(struct dentry *child) |
909 | { | |
2b0143b5 | 910 | struct inode *child_inode = d_inode(child); |
33670fa2 MS |
911 | struct fuse_conn *fc = get_fuse_conn(child_inode); |
912 | struct inode *inode; | |
913 | struct dentry *parent; | |
914 | struct fuse_entry_out outarg; | |
33670fa2 MS |
915 | int err; |
916 | ||
917 | if (!fc->export_support) | |
918 | return ERR_PTR(-ESTALE); | |
919 | ||
33670fa2 | 920 | err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode), |
80e5d1ff | 921 | &dotdot_name, &outarg, &inode); |
44003728 CH |
922 | if (err) { |
923 | if (err == -ENOENT) | |
924 | return ERR_PTR(-ESTALE); | |
33670fa2 | 925 | return ERR_PTR(err); |
33670fa2 | 926 | } |
44003728 CH |
927 | |
928 | parent = d_obtain_alias(inode); | |
c35eebe9 | 929 | if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID) |
33670fa2 | 930 | fuse_invalidate_entry_cache(parent); |
33670fa2 MS |
931 | |
932 | return parent; | |
933 | } | |
dbd561d2 MS |
934 | |
935 | static const struct export_operations fuse_export_operations = { | |
936 | .fh_to_dentry = fuse_fh_to_dentry, | |
937 | .fh_to_parent = fuse_fh_to_parent, | |
938 | .encode_fh = fuse_encode_fh, | |
33670fa2 | 939 | .get_parent = fuse_get_parent, |
dbd561d2 MS |
940 | }; |
941 | ||
ee9b6d61 | 942 | static const struct super_operations fuse_super_operations = { |
d8a5ba45 | 943 | .alloc_inode = fuse_alloc_inode, |
9baf28bb | 944 | .free_inode = fuse_free_inode, |
b57922d9 | 945 | .evict_inode = fuse_evict_inode, |
1e18bda8 | 946 | .write_inode = fuse_write_inode, |
ead5f0b5 | 947 | .drop_inode = generic_delete_inode, |
d8a5ba45 | 948 | .put_super = fuse_put_super, |
69a53bf2 | 949 | .umount_begin = fuse_umount_begin, |
e5e5558e | 950 | .statfs = fuse_statfs, |
2d82ab25 | 951 | .sync_fs = fuse_sync_fs, |
d8a5ba45 MS |
952 | .show_options = fuse_show_options, |
953 | }; | |
954 | ||
487ea5af CH |
955 | static void sanitize_global_limit(unsigned *limit) |
956 | { | |
f22f812d MS |
957 | /* |
958 | * The default maximum number of async requests is calculated to consume | |
959 | * 1/2^13 of the total memory, assuming 392 bytes per request. | |
960 | */ | |
487ea5af | 961 | if (*limit == 0) |
f22f812d | 962 | *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 392; |
487ea5af CH |
963 | |
964 | if (*limit >= 1 << 16) | |
965 | *limit = (1 << 16) - 1; | |
966 | } | |
967 | ||
e4dca7b7 | 968 | static int set_global_limit(const char *val, const struct kernel_param *kp) |
487ea5af CH |
969 | { |
970 | int rv; | |
971 | ||
972 | rv = param_set_uint(val, kp); | |
973 | if (rv) | |
974 | return rv; | |
975 | ||
976 | sanitize_global_limit((unsigned *)kp->arg); | |
977 | ||
978 | return 0; | |
979 | } | |
980 | ||
981 | static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg) | |
982 | { | |
983 | int cap_sys_admin = capable(CAP_SYS_ADMIN); | |
984 | ||
985 | if (arg->minor < 13) | |
986 | return; | |
987 | ||
988 | sanitize_global_limit(&max_user_bgreq); | |
989 | sanitize_global_limit(&max_user_congthresh); | |
990 | ||
ae2dffa3 | 991 | spin_lock(&fc->bg_lock); |
487ea5af CH |
992 | if (arg->max_background) { |
993 | fc->max_background = arg->max_background; | |
994 | ||
995 | if (!cap_sys_admin && fc->max_background > max_user_bgreq) | |
996 | fc->max_background = max_user_bgreq; | |
997 | } | |
998 | if (arg->congestion_threshold) { | |
999 | fc->congestion_threshold = arg->congestion_threshold; | |
1000 | ||
1001 | if (!cap_sys_admin && | |
1002 | fc->congestion_threshold > max_user_congthresh) | |
1003 | fc->congestion_threshold = max_user_congthresh; | |
1004 | } | |
ae2dffa3 | 1005 | spin_unlock(&fc->bg_lock); |
487ea5af CH |
1006 | } |
1007 | ||
615047ef MS |
1008 | struct fuse_init_args { |
1009 | struct fuse_args args; | |
1010 | struct fuse_init_in in; | |
1011 | struct fuse_init_out out; | |
1012 | }; | |
1013 | ||
fcee216b | 1014 | static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args, |
615047ef | 1015 | int error) |
9b9a0469 | 1016 | { |
fcee216b | 1017 | struct fuse_conn *fc = fm->fc; |
615047ef MS |
1018 | struct fuse_init_args *ia = container_of(args, typeof(*ia), args); |
1019 | struct fuse_init_out *arg = &ia->out; | |
fd1a1dc6 | 1020 | bool ok = true; |
9b9a0469 | 1021 | |
615047ef | 1022 | if (error || arg->major != FUSE_KERNEL_VERSION) |
fd1a1dc6 | 1023 | ok = false; |
9b9a0469 | 1024 | else { |
9cd68455 MS |
1025 | unsigned long ra_pages; |
1026 | ||
487ea5af CH |
1027 | process_init_limits(fc, arg); |
1028 | ||
9cd68455 | 1029 | if (arg->minor >= 6) { |
09cbfeaf | 1030 | ra_pages = arg->max_readahead / PAGE_SIZE; |
9cd68455 MS |
1031 | if (arg->flags & FUSE_ASYNC_READ) |
1032 | fc->async_read = 1; | |
71421259 MS |
1033 | if (!(arg->flags & FUSE_POSIX_LOCKS)) |
1034 | fc->no_lock = 1; | |
37fb3a30 MS |
1035 | if (arg->minor >= 17) { |
1036 | if (!(arg->flags & FUSE_FLOCK_LOCKS)) | |
1037 | fc->no_flock = 1; | |
24114504 MS |
1038 | } else { |
1039 | if (!(arg->flags & FUSE_POSIX_LOCKS)) | |
1040 | fc->no_flock = 1; | |
37fb3a30 | 1041 | } |
6ff958ed MS |
1042 | if (arg->flags & FUSE_ATOMIC_O_TRUNC) |
1043 | fc->atomic_o_trunc = 1; | |
33670fa2 MS |
1044 | if (arg->minor >= 9) { |
1045 | /* LOOKUP has dependency on proto version */ | |
1046 | if (arg->flags & FUSE_EXPORT_SUPPORT) | |
1047 | fc->export_support = 1; | |
1048 | } | |
78bb6cb9 MS |
1049 | if (arg->flags & FUSE_BIG_WRITES) |
1050 | fc->big_writes = 1; | |
e0a43ddc MS |
1051 | if (arg->flags & FUSE_DONT_MASK) |
1052 | fc->dont_mask = 1; | |
72d0d248 BF |
1053 | if (arg->flags & FUSE_AUTO_INVAL_DATA) |
1054 | fc->auto_inval_data = 1; | |
ad2ba64d KS |
1055 | else if (arg->flags & FUSE_EXPLICIT_INVAL_DATA) |
1056 | fc->explicit_inval_data = 1; | |
28420dad | 1057 | if (arg->flags & FUSE_DO_READDIRPLUS) { |
0b05b183 | 1058 | fc->do_readdirplus = 1; |
28420dad MS |
1059 | if (arg->flags & FUSE_READDIRPLUS_AUTO) |
1060 | fc->readdirplus_auto = 1; | |
1061 | } | |
60b9df7a MS |
1062 | if (arg->flags & FUSE_ASYNC_DIO) |
1063 | fc->async_dio = 1; | |
4d99ff8f PE |
1064 | if (arg->flags & FUSE_WRITEBACK_CACHE) |
1065 | fc->writeback_cache = 1; | |
5c672ab3 MS |
1066 | if (arg->flags & FUSE_PARALLEL_DIROPS) |
1067 | fc->parallel_dirops = 1; | |
5e940c1d MS |
1068 | if (arg->flags & FUSE_HANDLE_KILLPRIV) |
1069 | fc->handle_killpriv = 1; | |
e27c9d38 | 1070 | if (arg->time_gran && arg->time_gran <= 1000000000) |
fcee216b | 1071 | fm->sb->s_time_gran = arg->time_gran; |
60bcc88a | 1072 | if ((arg->flags & FUSE_POSIX_ACL)) { |
29433a29 | 1073 | fc->default_permissions = 1; |
60bcc88a | 1074 | fc->posix_acl = 1; |
fcee216b | 1075 | fm->sb->s_xattr = fuse_acl_xattr_handlers; |
60bcc88a | 1076 | } |
5571f1e6 DS |
1077 | if (arg->flags & FUSE_CACHE_SYMLINKS) |
1078 | fc->cache_symlinks = 1; | |
3b7008b2 SL |
1079 | if (arg->flags & FUSE_ABORT_ERROR) |
1080 | fc->abort_err = 1; | |
5da784cc CS |
1081 | if (arg->flags & FUSE_MAX_PAGES) { |
1082 | fc->max_pages = | |
a7f0d7aa | 1083 | min_t(unsigned int, fc->max_pages_limit, |
5da784cc CS |
1084 | max_t(unsigned int, arg->max_pages, 1)); |
1085 | } | |
fd1a1dc6 SH |
1086 | if (IS_ENABLED(CONFIG_FUSE_DAX) && |
1087 | arg->flags & FUSE_MAP_ALIGNMENT && | |
1088 | !fuse_dax_check_alignment(fc, arg->map_alignment)) { | |
1089 | ok = false; | |
1090 | } | |
9d769e6a | 1091 | if (arg->flags & FUSE_HANDLE_KILLPRIV_V2) { |
63f9909f | 1092 | fc->handle_killpriv_v2 = 1; |
9d769e6a VG |
1093 | fm->sb->s_flags |= SB_NOSEC; |
1094 | } | |
52a4c95f VG |
1095 | if (arg->flags & FUSE_SETXATTR_EXT) |
1096 | fc->setxattr_ext = 1; | |
71421259 | 1097 | } else { |
09cbfeaf | 1098 | ra_pages = fc->max_read / PAGE_SIZE; |
71421259 | 1099 | fc->no_lock = 1; |
37fb3a30 | 1100 | fc->no_flock = 1; |
71421259 | 1101 | } |
9cd68455 | 1102 | |
fcee216b MR |
1103 | fm->sb->s_bdi->ra_pages = |
1104 | min(fm->sb->s_bdi->ra_pages, ra_pages); | |
9b9a0469 MS |
1105 | fc->minor = arg->minor; |
1106 | fc->max_write = arg->minor < 5 ? 4096 : arg->max_write; | |
f948d564 | 1107 | fc->max_write = max_t(unsigned, 4096, fc->max_write); |
0ec7ca41 | 1108 | fc->conn_init = 1; |
9b9a0469 | 1109 | } |
615047ef MS |
1110 | kfree(ia); |
1111 | ||
fd1a1dc6 SH |
1112 | if (!ok) { |
1113 | fc->conn_init = 0; | |
1114 | fc->conn_error = 1; | |
1115 | } | |
1116 | ||
9759bd51 | 1117 | fuse_set_initialized(fc); |
08a53cdc | 1118 | wake_up_all(&fc->blocked_waitq); |
9b9a0469 MS |
1119 | } |
1120 | ||
fcee216b | 1121 | void fuse_send_init(struct fuse_mount *fm) |
9b9a0469 | 1122 | { |
615047ef | 1123 | struct fuse_init_args *ia; |
095da6cb | 1124 | |
615047ef MS |
1125 | ia = kzalloc(sizeof(*ia), GFP_KERNEL | __GFP_NOFAIL); |
1126 | ||
1127 | ia->in.major = FUSE_KERNEL_VERSION; | |
1128 | ia->in.minor = FUSE_KERNEL_MINOR_VERSION; | |
fcee216b | 1129 | ia->in.max_readahead = fm->sb->s_bdi->ra_pages * PAGE_SIZE; |
615047ef MS |
1130 | ia->in.flags |= |
1131 | FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC | | |
37fb3a30 | 1132 | FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK | |
69fe05c9 | 1133 | FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ | |
9446385f | 1134 | FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA | |
4d99ff8f | 1135 | FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO | |
5c672ab3 | 1136 | FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT | |
3b7008b2 | 1137 | FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL | |
d9a9ea94 | 1138 | FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS | |
63f9909f | 1139 | FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA | |
52a4c95f | 1140 | FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT; |
fd1a1dc6 | 1141 | #ifdef CONFIG_FUSE_DAX |
fcee216b | 1142 | if (fm->fc->dax) |
fd1a1dc6 SH |
1143 | ia->in.flags |= FUSE_MAP_ALIGNMENT; |
1144 | #endif | |
bf109c64 MR |
1145 | if (fm->fc->auto_submounts) |
1146 | ia->in.flags |= FUSE_SUBMOUNTS; | |
1147 | ||
615047ef MS |
1148 | ia->args.opcode = FUSE_INIT; |
1149 | ia->args.in_numargs = 1; | |
1150 | ia->args.in_args[0].size = sizeof(ia->in); | |
1151 | ia->args.in_args[0].value = &ia->in; | |
1152 | ia->args.out_numargs = 1; | |
3ad2f3fb | 1153 | /* Variable length argument used for backward compatibility |
9b9a0469 MS |
1154 | with interface version < 7.5. Rest of init_out is zeroed |
1155 | by do_get_request(), so a short reply is not a problem */ | |
cabdb4fa | 1156 | ia->args.out_argvar = true; |
615047ef MS |
1157 | ia->args.out_args[0].size = sizeof(ia->out); |
1158 | ia->args.out_args[0].value = &ia->out; | |
1159 | ia->args.force = true; | |
1160 | ia->args.nocreds = true; | |
1161 | ia->args.end = process_init_reply; | |
1162 | ||
fcee216b MR |
1163 | if (fuse_simple_background(fm, &ia->args, GFP_KERNEL) != 0) |
1164 | process_init_reply(fm, &ia->args, -ENOTCONN); | |
9b9a0469 | 1165 | } |
95a84cdb | 1166 | EXPORT_SYMBOL_GPL(fuse_send_init); |
9b9a0469 | 1167 | |
783863d6 | 1168 | void fuse_free_conn(struct fuse_conn *fc) |
43901aab | 1169 | { |
cc080e9e | 1170 | WARN_ON(!list_empty(&fc->devices)); |
dd3e2c55 | 1171 | kfree_rcu(fc, rcu); |
43901aab | 1172 | } |
783863d6 | 1173 | EXPORT_SYMBOL_GPL(fuse_free_conn); |
43901aab | 1174 | |
a325f9b9 TH |
1175 | static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb) |
1176 | { | |
1177 | int err; | |
5f7f7543 | 1178 | char *suffix = ""; |
a325f9b9 | 1179 | |
69c8ebf8 | 1180 | if (sb->s_bdev) { |
5f7f7543 | 1181 | suffix = "-fuseblk"; |
69c8ebf8 JK |
1182 | /* |
1183 | * sb->s_bdi points to blkdev's bdi however we want to redirect | |
1184 | * it to our private bdi... | |
1185 | */ | |
1186 | bdi_put(sb->s_bdi); | |
1187 | sb->s_bdi = &noop_backing_dev_info; | |
1188 | } | |
5f7f7543 JK |
1189 | err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev), |
1190 | MINOR(fc->dev), suffix); | |
a325f9b9 TH |
1191 | if (err) |
1192 | return err; | |
1193 | ||
5f7f7543 | 1194 | /* fuse does it's own writeback accounting */ |
823423ef CH |
1195 | sb->s_bdi->capabilities &= ~BDI_CAP_WRITEBACK_ACCT; |
1196 | sb->s_bdi->capabilities |= BDI_CAP_STRICTLIMIT; | |
a325f9b9 | 1197 | |
a325f9b9 TH |
1198 | /* |
1199 | * For a single fuse filesystem use max 1% of dirty + | |
1200 | * writeback threshold. | |
1201 | * | |
1202 | * This gives about 1M of write buffer for memory maps on a | |
1203 | * machine with 1G and 10% dirty_ratio, which should be more | |
1204 | * than enough. | |
1205 | * | |
1206 | * Privileged users can raise it by writing to | |
1207 | * | |
1208 | * /sys/class/bdi/<bdi>/max_ratio | |
1209 | */ | |
5f7f7543 | 1210 | bdi_set_max_ratio(sb->s_bdi, 1); |
a325f9b9 TH |
1211 | |
1212 | return 0; | |
1213 | } | |
1214 | ||
0cd1eb9a | 1215 | struct fuse_dev *fuse_dev_alloc(void) |
cc080e9e MS |
1216 | { |
1217 | struct fuse_dev *fud; | |
be2ff42c | 1218 | struct list_head *pq; |
cc080e9e MS |
1219 | |
1220 | fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL); | |
be2ff42c KT |
1221 | if (!fud) |
1222 | return NULL; | |
cc080e9e | 1223 | |
be2ff42c KT |
1224 | pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL); |
1225 | if (!pq) { | |
1226 | kfree(fud); | |
1227 | return NULL; | |
cc080e9e MS |
1228 | } |
1229 | ||
be2ff42c | 1230 | fud->pq.processing = pq; |
be2ff42c KT |
1231 | fuse_pqueue_init(&fud->pq); |
1232 | ||
0cd1eb9a VG |
1233 | return fud; |
1234 | } | |
1235 | EXPORT_SYMBOL_GPL(fuse_dev_alloc); | |
1236 | ||
1237 | void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc) | |
1238 | { | |
1239 | fud->fc = fuse_conn_get(fc); | |
be2ff42c KT |
1240 | spin_lock(&fc->lock); |
1241 | list_add_tail(&fud->entry, &fc->devices); | |
1242 | spin_unlock(&fc->lock); | |
0cd1eb9a VG |
1243 | } |
1244 | EXPORT_SYMBOL_GPL(fuse_dev_install); | |
be2ff42c | 1245 | |
0cd1eb9a VG |
1246 | struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc) |
1247 | { | |
1248 | struct fuse_dev *fud; | |
1249 | ||
1250 | fud = fuse_dev_alloc(); | |
1251 | if (!fud) | |
1252 | return NULL; | |
1253 | ||
1254 | fuse_dev_install(fud, fc); | |
cc080e9e MS |
1255 | return fud; |
1256 | } | |
0cd1eb9a | 1257 | EXPORT_SYMBOL_GPL(fuse_dev_alloc_install); |
cc080e9e MS |
1258 | |
1259 | void fuse_dev_free(struct fuse_dev *fud) | |
1260 | { | |
1261 | struct fuse_conn *fc = fud->fc; | |
1262 | ||
1263 | if (fc) { | |
1264 | spin_lock(&fc->lock); | |
1265 | list_del(&fud->entry); | |
1266 | spin_unlock(&fc->lock); | |
1267 | ||
1268 | fuse_conn_put(fc); | |
1269 | } | |
d72f70da | 1270 | kfree(fud->pq.processing); |
cc080e9e MS |
1271 | kfree(fud); |
1272 | } | |
1273 | EXPORT_SYMBOL_GPL(fuse_dev_free); | |
1274 | ||
1866d779 MR |
1275 | static void fuse_fill_attr_from_inode(struct fuse_attr *attr, |
1276 | const struct fuse_inode *fi) | |
1277 | { | |
1278 | *attr = (struct fuse_attr){ | |
1279 | .ino = fi->inode.i_ino, | |
1280 | .size = fi->inode.i_size, | |
1281 | .blocks = fi->inode.i_blocks, | |
1282 | .atime = fi->inode.i_atime.tv_sec, | |
1283 | .mtime = fi->inode.i_mtime.tv_sec, | |
1284 | .ctime = fi->inode.i_ctime.tv_sec, | |
1285 | .atimensec = fi->inode.i_atime.tv_nsec, | |
1286 | .mtimensec = fi->inode.i_mtime.tv_nsec, | |
1287 | .ctimensec = fi->inode.i_ctime.tv_nsec, | |
1288 | .mode = fi->inode.i_mode, | |
1289 | .nlink = fi->inode.i_nlink, | |
1290 | .uid = fi->inode.i_uid.val, | |
1291 | .gid = fi->inode.i_gid.val, | |
1292 | .rdev = fi->inode.i_rdev, | |
1293 | .blksize = 1u << fi->inode.i_blkbits, | |
1294 | }; | |
1295 | } | |
1296 | ||
1297 | static void fuse_sb_defaults(struct super_block *sb) | |
1298 | { | |
1299 | sb->s_magic = FUSE_SUPER_MAGIC; | |
1300 | sb->s_op = &fuse_super_operations; | |
1301 | sb->s_xattr = fuse_xattr_handlers; | |
1302 | sb->s_maxbytes = MAX_LFS_FILESIZE; | |
1303 | sb->s_time_gran = 1; | |
1304 | sb->s_export_op = &fuse_export_operations; | |
1305 | sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE; | |
1306 | if (sb->s_user_ns != &init_user_ns) | |
1307 | sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER; | |
1308 | sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION); | |
1309 | ||
1310 | /* | |
1311 | * If we are not in the initial user namespace posix | |
1312 | * acls must be translated. | |
1313 | */ | |
1314 | if (sb->s_user_ns != &init_user_ns) | |
1315 | sb->s_xattr = fuse_no_acl_xattr_handlers; | |
1316 | } | |
1317 | ||
1b539917 GK |
1318 | static int fuse_fill_super_submount(struct super_block *sb, |
1319 | struct fuse_inode *parent_fi) | |
1866d779 MR |
1320 | { |
1321 | struct fuse_mount *fm = get_fuse_mount_super(sb); | |
1322 | struct super_block *parent_sb = parent_fi->inode.i_sb; | |
1323 | struct fuse_attr root_attr; | |
1324 | struct inode *root; | |
1325 | ||
1326 | fuse_sb_defaults(sb); | |
1327 | fm->sb = sb; | |
1328 | ||
1329 | WARN_ON(sb->s_bdi != &noop_backing_dev_info); | |
1330 | sb->s_bdi = bdi_get(parent_sb->s_bdi); | |
1331 | ||
1332 | sb->s_xattr = parent_sb->s_xattr; | |
1333 | sb->s_time_gran = parent_sb->s_time_gran; | |
1334 | sb->s_blocksize = parent_sb->s_blocksize; | |
1335 | sb->s_blocksize_bits = parent_sb->s_blocksize_bits; | |
1336 | sb->s_subtype = kstrdup(parent_sb->s_subtype, GFP_KERNEL); | |
1337 | if (parent_sb->s_subtype && !sb->s_subtype) | |
1338 | return -ENOMEM; | |
1339 | ||
1340 | fuse_fill_attr_from_inode(&root_attr, parent_fi); | |
1341 | root = fuse_iget(sb, parent_fi->nodeid, 0, &root_attr, 0, 0); | |
1342 | /* | |
1343 | * This inode is just a duplicate, so it is not looked up and | |
1344 | * its nlookup should not be incremented. fuse_iget() does | |
1345 | * that, though, so undo it here. | |
1346 | */ | |
1347 | get_fuse_inode(root)->nlookup--; | |
1348 | sb->s_d_op = &fuse_dentry_operations; | |
1349 | sb->s_root = d_make_root(root); | |
1350 | if (!sb->s_root) | |
1351 | return -ENOMEM; | |
1352 | ||
1353 | return 0; | |
1354 | } | |
1355 | ||
266eb3f2 | 1356 | /* Filesystem context private data holds the FUSE inode of the mount point */ |
fe0a7bd8 GK |
1357 | static int fuse_get_tree_submount(struct fs_context *fsc) |
1358 | { | |
266eb3f2 GK |
1359 | struct fuse_mount *fm; |
1360 | struct fuse_inode *mp_fi = fsc->fs_private; | |
1361 | struct fuse_conn *fc = get_fuse_conn(&mp_fi->inode); | |
1362 | struct super_block *sb; | |
1363 | int err; | |
1364 | ||
1365 | fm = kzalloc(sizeof(struct fuse_mount), GFP_KERNEL); | |
1366 | if (!fm) | |
1367 | return -ENOMEM; | |
1368 | ||
1369 | fsc->s_fs_info = fm; | |
1370 | sb = sget_fc(fsc, NULL, set_anon_super_fc); | |
1371 | if (IS_ERR(sb)) { | |
1372 | kfree(fm); | |
1373 | return PTR_ERR(sb); | |
1374 | } | |
1375 | fm->fc = fuse_conn_get(fc); | |
1376 | ||
1377 | /* Initialize superblock, making @mp_fi its root */ | |
1378 | err = fuse_fill_super_submount(sb, mp_fi); | |
1379 | if (err) { | |
1380 | fuse_conn_put(fc); | |
1381 | kfree(fm); | |
1382 | sb->s_fs_info = NULL; | |
1383 | deactivate_locked_super(sb); | |
1384 | return err; | |
1385 | } | |
1386 | ||
1387 | down_write(&fc->killsb); | |
1388 | list_add_tail(&fm->fc_entry, &fc->mounts); | |
1389 | up_write(&fc->killsb); | |
1390 | ||
1391 | sb->s_flags |= SB_ACTIVE; | |
1392 | fsc->root = dget(sb->s_root); | |
1393 | ||
fe0a7bd8 GK |
1394 | return 0; |
1395 | } | |
1396 | ||
1397 | static const struct fs_context_operations fuse_context_submount_ops = { | |
1398 | .get_tree = fuse_get_tree_submount, | |
1399 | }; | |
1400 | ||
1401 | int fuse_init_fs_context_submount(struct fs_context *fsc) | |
1402 | { | |
1403 | fsc->ops = &fuse_context_submount_ops; | |
1404 | return 0; | |
1405 | } | |
1406 | EXPORT_SYMBOL_GPL(fuse_init_fs_context_submount); | |
1407 | ||
0cc2656c | 1408 | int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx) |
d8a5ba45 | 1409 | { |
7fd3abfa | 1410 | struct fuse_dev *fud = NULL; |
fcee216b MR |
1411 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
1412 | struct fuse_conn *fc = fm->fc; | |
d8a5ba45 | 1413 | struct inode *root; |
f543f253 | 1414 | struct dentry *root_dentry; |
d8a5ba45 MS |
1415 | int err; |
1416 | ||
c2b8f006 | 1417 | err = -EINVAL; |
1751e8a6 | 1418 | if (sb->s_flags & SB_MANDLOCK) |
c2b8f006 | 1419 | goto err; |
71421259 | 1420 | |
1866d779 | 1421 | fuse_sb_defaults(sb); |
9e1f1de0 | 1422 | |
0cc2656c | 1423 | if (ctx->is_bdev) { |
875d95ec | 1424 | #ifdef CONFIG_BLOCK |
c2b8f006 | 1425 | err = -EINVAL; |
c30da2e9 | 1426 | if (!sb_set_blocksize(sb, ctx->blksize)) |
c2b8f006 | 1427 | goto err; |
875d95ec | 1428 | #endif |
d8091614 | 1429 | } else { |
09cbfeaf KS |
1430 | sb->s_blocksize = PAGE_SIZE; |
1431 | sb->s_blocksize_bits = PAGE_SHIFT; | |
d8091614 | 1432 | } |
c30da2e9 DH |
1433 | |
1434 | sb->s_subtype = ctx->subtype; | |
1435 | ctx->subtype = NULL; | |
1dd53957 VG |
1436 | if (IS_ENABLED(CONFIG_FUSE_DAX)) { |
1437 | err = fuse_dax_conn_alloc(fc, ctx->dax_dev); | |
1438 | if (err) | |
1439 | goto err; | |
1440 | } | |
e45b2546 | 1441 | |
7fd3abfa VG |
1442 | if (ctx->fudptr) { |
1443 | err = -ENOMEM; | |
1444 | fud = fuse_dev_alloc_install(fc); | |
1445 | if (!fud) | |
1dd53957 | 1446 | goto err_free_dax; |
7fd3abfa | 1447 | } |
cc080e9e | 1448 | |
a325f9b9 | 1449 | fc->dev = sb->s_dev; |
fcee216b | 1450 | fm->sb = sb; |
a325f9b9 TH |
1451 | err = fuse_bdi_init(fc, sb); |
1452 | if (err) | |
cc080e9e | 1453 | goto err_dev_free; |
0d179aa5 | 1454 | |
e0a43ddc | 1455 | /* Handle umasking inside the fuse code */ |
1751e8a6 | 1456 | if (sb->s_flags & SB_POSIXACL) |
e0a43ddc | 1457 | fc->dont_mask = 1; |
1751e8a6 | 1458 | sb->s_flags |= SB_POSIXACL; |
e0a43ddc | 1459 | |
c30da2e9 DH |
1460 | fc->default_permissions = ctx->default_permissions; |
1461 | fc->allow_other = ctx->allow_other; | |
1462 | fc->user_id = ctx->user_id; | |
1463 | fc->group_id = ctx->group_id; | |
f4fd4ae3 | 1464 | fc->legacy_opts_show = ctx->legacy_opts_show; |
1866d779 | 1465 | fc->max_read = max_t(unsigned int, 4096, ctx->max_read); |
783863d6 | 1466 | fc->destroy = ctx->destroy; |
15c8e72e VG |
1467 | fc->no_control = ctx->no_control; |
1468 | fc->no_force_umount = ctx->no_force_umount; | |
f543f253 | 1469 | |
d8a5ba45 | 1470 | err = -ENOMEM; |
c30da2e9 | 1471 | root = fuse_get_root_inode(sb, ctx->rootmode); |
0ce267ff | 1472 | sb->s_d_op = &fuse_root_dentry_operations; |
48fde701 AV |
1473 | root_dentry = d_make_root(root); |
1474 | if (!root_dentry) | |
cc080e9e | 1475 | goto err_dev_free; |
0ce267ff | 1476 | /* Root dentry doesn't have .d_revalidate */ |
c35eebe9 | 1477 | sb->s_d_op = &fuse_dentry_operations; |
f543f253 | 1478 | |
bafa9654 | 1479 | mutex_lock(&fuse_mutex); |
8aa09a50 | 1480 | err = -EINVAL; |
7fd3abfa | 1481 | if (ctx->fudptr && *ctx->fudptr) |
bafa9654 | 1482 | goto err_unlock; |
8aa09a50 | 1483 | |
bafa9654 MS |
1484 | err = fuse_ctl_add_conn(fc); |
1485 | if (err) | |
1486 | goto err_unlock; | |
1487 | ||
1488 | list_add_tail(&fc->entry, &fuse_conn_list); | |
f543f253 | 1489 | sb->s_root = root_dentry; |
7fd3abfa VG |
1490 | if (ctx->fudptr) |
1491 | *ctx->fudptr = fud; | |
bafa9654 | 1492 | mutex_unlock(&fuse_mutex); |
0cc2656c SH |
1493 | return 0; |
1494 | ||
1495 | err_unlock: | |
1496 | mutex_unlock(&fuse_mutex); | |
1497 | dput(root_dentry); | |
1498 | err_dev_free: | |
7fd3abfa VG |
1499 | if (fud) |
1500 | fuse_dev_free(fud); | |
1dd53957 VG |
1501 | err_free_dax: |
1502 | if (IS_ENABLED(CONFIG_FUSE_DAX)) | |
1503 | fuse_dax_conn_free(fc); | |
0cc2656c SH |
1504 | err: |
1505 | return err; | |
1506 | } | |
1507 | EXPORT_SYMBOL_GPL(fuse_fill_super_common); | |
1508 | ||
1509 | static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) | |
1510 | { | |
1511 | struct fuse_fs_context *ctx = fsc->fs_private; | |
0cc2656c SH |
1512 | int err; |
1513 | struct fuse_conn *fc; | |
fcee216b | 1514 | struct fuse_mount *fm; |
0cc2656c | 1515 | |
62dd1fc8 | 1516 | if (!ctx->file || !ctx->rootmode_present || |
badc7414 MS |
1517 | !ctx->user_id_present || !ctx->group_id_present) |
1518 | return -EINVAL; | |
1519 | ||
0cc2656c SH |
1520 | /* |
1521 | * Require mount to happen from the same user namespace which | |
1522 | * opened /dev/fuse to prevent potential attacks. | |
1523 | */ | |
62dd1fc8 MS |
1524 | err = -EINVAL; |
1525 | if ((ctx->file->f_op != &fuse_dev_operations) || | |
1526 | (ctx->file->f_cred->user_ns != sb->s_user_ns)) | |
1527 | goto err; | |
1528 | ctx->fudptr = &ctx->file->private_data; | |
0cc2656c SH |
1529 | |
1530 | fc = kmalloc(sizeof(*fc), GFP_KERNEL); | |
1531 | err = -ENOMEM; | |
1532 | if (!fc) | |
62dd1fc8 | 1533 | goto err; |
0cc2656c | 1534 | |
fcee216b MR |
1535 | fm = kzalloc(sizeof(*fm), GFP_KERNEL); |
1536 | if (!fm) { | |
1537 | kfree(fc); | |
62dd1fc8 | 1538 | goto err; |
fcee216b MR |
1539 | } |
1540 | ||
1541 | fuse_conn_init(fc, fm, sb->s_user_ns, &fuse_dev_fiq_ops, NULL); | |
0cc2656c | 1542 | fc->release = fuse_free_conn; |
fcee216b MR |
1543 | |
1544 | sb->s_fs_info = fm; | |
0cc2656c SH |
1545 | |
1546 | err = fuse_fill_super_common(sb, ctx); | |
1547 | if (err) | |
1548 | goto err_put_conn; | |
62dd1fc8 MS |
1549 | /* file->private_data shall be visible on all CPUs after this */ |
1550 | smp_mb(); | |
fcee216b | 1551 | fuse_send_init(get_fuse_mount_super(sb)); |
d8a5ba45 MS |
1552 | return 0; |
1553 | ||
c2b8f006 | 1554 | err_put_conn: |
514b5e3f MS |
1555 | fuse_conn_put(fc); |
1556 | kfree(fm); | |
543b8f86 | 1557 | sb->s_fs_info = NULL; |
c2b8f006 | 1558 | err: |
d8a5ba45 MS |
1559 | return err; |
1560 | } | |
1561 | ||
5d5b74aa MS |
1562 | /* |
1563 | * This is the path where user supplied an already initialized fuse dev. In | |
1564 | * this case never create a new super if the old one is gone. | |
1565 | */ | |
1566 | static int fuse_set_no_super(struct super_block *sb, struct fs_context *fsc) | |
1567 | { | |
1568 | return -ENOTCONN; | |
1569 | } | |
1570 | ||
1571 | static int fuse_test_super(struct super_block *sb, struct fs_context *fsc) | |
1572 | { | |
1573 | ||
1574 | return fsc->sget_key == get_fuse_conn_super(sb); | |
1575 | } | |
1576 | ||
84c21507 | 1577 | static int fuse_get_tree(struct fs_context *fsc) |
d8a5ba45 | 1578 | { |
84c21507 | 1579 | struct fuse_fs_context *ctx = fsc->fs_private; |
5d5b74aa MS |
1580 | struct fuse_dev *fud; |
1581 | struct super_block *sb; | |
62dd1fc8 MS |
1582 | int err; |
1583 | ||
1584 | if (ctx->fd_present) | |
1585 | ctx->file = fget(ctx->fd); | |
c30da2e9 | 1586 | |
badc7414 | 1587 | if (IS_ENABLED(CONFIG_BLOCK) && ctx->is_bdev) { |
62dd1fc8 MS |
1588 | err = get_tree_bdev(fsc, fuse_fill_super); |
1589 | goto out_fput; | |
badc7414 | 1590 | } |
5d5b74aa MS |
1591 | /* |
1592 | * While block dev mount can be initialized with a dummy device fd | |
1593 | * (found by device name), normal fuse mounts can't | |
1594 | */ | |
1595 | if (!ctx->file) | |
1596 | return -EINVAL; | |
c30da2e9 | 1597 | |
5d5b74aa MS |
1598 | /* |
1599 | * Allow creating a fuse mount with an already initialized fuse | |
1600 | * connection | |
1601 | */ | |
1602 | fud = READ_ONCE(ctx->file->private_data); | |
1603 | if (ctx->file->f_op == &fuse_dev_operations && fud) { | |
1604 | fsc->sget_key = fud->fc; | |
1605 | sb = sget_fc(fsc, fuse_test_super, fuse_set_no_super); | |
1606 | err = PTR_ERR_OR_ZERO(sb); | |
1607 | if (!IS_ERR(sb)) | |
1608 | fsc->root = dget(sb->s_root); | |
1609 | } else { | |
1610 | err = get_tree_nodev(fsc, fuse_fill_super); | |
1611 | } | |
62dd1fc8 MS |
1612 | out_fput: |
1613 | if (ctx->file) | |
1614 | fput(ctx->file); | |
1615 | return err; | |
c30da2e9 DH |
1616 | } |
1617 | ||
1618 | static const struct fs_context_operations fuse_context_ops = { | |
84c21507 | 1619 | .free = fuse_free_fsc, |
c30da2e9 | 1620 | .parse_param = fuse_parse_param, |
0189a2d3 | 1621 | .reconfigure = fuse_reconfigure, |
c30da2e9 DH |
1622 | .get_tree = fuse_get_tree, |
1623 | }; | |
1624 | ||
1625 | /* | |
1626 | * Set up the filesystem mount context. | |
1627 | */ | |
84c21507 | 1628 | static int fuse_init_fs_context(struct fs_context *fsc) |
c30da2e9 DH |
1629 | { |
1630 | struct fuse_fs_context *ctx; | |
1631 | ||
1632 | ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL); | |
1633 | if (!ctx) | |
1634 | return -ENOMEM; | |
1635 | ||
1636 | ctx->max_read = ~0; | |
1637 | ctx->blksize = FUSE_DEFAULT_BLKSIZE; | |
f4fd4ae3 | 1638 | ctx->legacy_opts_show = true; |
c30da2e9 DH |
1639 | |
1640 | #ifdef CONFIG_BLOCK | |
84c21507 | 1641 | if (fsc->fs_type == &fuseblk_fs_type) { |
c30da2e9 | 1642 | ctx->is_bdev = true; |
783863d6 MS |
1643 | ctx->destroy = true; |
1644 | } | |
c30da2e9 DH |
1645 | #endif |
1646 | ||
84c21507 MS |
1647 | fsc->fs_private = ctx; |
1648 | fsc->ops = &fuse_context_ops; | |
c30da2e9 | 1649 | return 0; |
d8a5ba45 MS |
1650 | } |
1651 | ||
fcee216b | 1652 | bool fuse_mount_remove(struct fuse_mount *fm) |
3b463ae0 | 1653 | { |
fcee216b MR |
1654 | struct fuse_conn *fc = fm->fc; |
1655 | bool last = false; | |
3b463ae0 | 1656 | |
fcee216b MR |
1657 | down_write(&fc->killsb); |
1658 | list_del_init(&fm->fc_entry); | |
1659 | if (list_empty(&fc->mounts)) | |
1660 | last = true; | |
1661 | up_write(&fc->killsb); | |
e8f3bd77 | 1662 | |
fcee216b MR |
1663 | return last; |
1664 | } | |
1665 | EXPORT_SYMBOL_GPL(fuse_mount_remove); | |
e8f3bd77 | 1666 | |
fcee216b MR |
1667 | void fuse_conn_destroy(struct fuse_mount *fm) |
1668 | { | |
1669 | struct fuse_conn *fc = fm->fc; | |
1670 | ||
1671 | if (fc->destroy) | |
1672 | fuse_send_destroy(fm); | |
1673 | ||
1674 | fuse_abort_conn(fc); | |
1675 | fuse_wait_aborted(fc); | |
413daa1a MS |
1676 | |
1677 | if (!list_empty(&fc->entry)) { | |
1678 | mutex_lock(&fuse_mutex); | |
1679 | list_del(&fc->entry); | |
1680 | fuse_ctl_remove_conn(fc); | |
1681 | mutex_unlock(&fuse_mutex); | |
3b463ae0 | 1682 | } |
e8f3bd77 | 1683 | } |
fcee216b | 1684 | EXPORT_SYMBOL_GPL(fuse_conn_destroy); |
3b463ae0 | 1685 | |
6a68d1e1 | 1686 | static void fuse_sb_destroy(struct super_block *sb) |
e8f3bd77 | 1687 | { |
fcee216b MR |
1688 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
1689 | bool last; | |
1690 | ||
1691 | if (fm) { | |
1692 | last = fuse_mount_remove(fm); | |
1693 | if (last) | |
1694 | fuse_conn_destroy(fm); | |
1695 | } | |
6a68d1e1 MS |
1696 | } |
1697 | ||
1698 | static void fuse_kill_sb_anon(struct super_block *sb) | |
1699 | { | |
1700 | fuse_sb_destroy(sb); | |
3b463ae0 JM |
1701 | kill_anon_super(sb); |
1702 | } | |
1703 | ||
875d95ec MS |
1704 | static struct file_system_type fuse_fs_type = { |
1705 | .owner = THIS_MODULE, | |
1706 | .name = "fuse", | |
4ad769f3 | 1707 | .fs_flags = FS_HAS_SUBTYPE | FS_USERNS_MOUNT, |
c30da2e9 | 1708 | .init_fs_context = fuse_init_fs_context, |
d7167b14 | 1709 | .parameters = fuse_fs_parameters, |
3b463ae0 | 1710 | .kill_sb = fuse_kill_sb_anon, |
875d95ec | 1711 | }; |
7f78e035 | 1712 | MODULE_ALIAS_FS("fuse"); |
875d95ec MS |
1713 | |
1714 | #ifdef CONFIG_BLOCK | |
3b463ae0 JM |
1715 | static void fuse_kill_sb_blk(struct super_block *sb) |
1716 | { | |
6a68d1e1 | 1717 | fuse_sb_destroy(sb); |
3b463ae0 JM |
1718 | kill_block_super(sb); |
1719 | } | |
1720 | ||
d6392f87 MS |
1721 | static struct file_system_type fuseblk_fs_type = { |
1722 | .owner = THIS_MODULE, | |
1723 | .name = "fuseblk", | |
c30da2e9 | 1724 | .init_fs_context = fuse_init_fs_context, |
d7167b14 | 1725 | .parameters = fuse_fs_parameters, |
3b463ae0 | 1726 | .kill_sb = fuse_kill_sb_blk, |
edad01e2 | 1727 | .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE, |
d6392f87 | 1728 | }; |
7f78e035 | 1729 | MODULE_ALIAS_FS("fuseblk"); |
d6392f87 | 1730 | |
875d95ec MS |
1731 | static inline int register_fuseblk(void) |
1732 | { | |
1733 | return register_filesystem(&fuseblk_fs_type); | |
1734 | } | |
1735 | ||
1736 | static inline void unregister_fuseblk(void) | |
1737 | { | |
1738 | unregister_filesystem(&fuseblk_fs_type); | |
1739 | } | |
1740 | #else | |
1741 | static inline int register_fuseblk(void) | |
1742 | { | |
1743 | return 0; | |
1744 | } | |
1745 | ||
1746 | static inline void unregister_fuseblk(void) | |
1747 | { | |
1748 | } | |
1749 | #endif | |
1750 | ||
51cc5068 | 1751 | static void fuse_inode_init_once(void *foo) |
d8a5ba45 | 1752 | { |
1729a16c | 1753 | struct inode *inode = foo; |
d8a5ba45 | 1754 | |
a35afb83 | 1755 | inode_init_once(inode); |
d8a5ba45 MS |
1756 | } |
1757 | ||
1758 | static int __init fuse_fs_init(void) | |
1759 | { | |
1760 | int err; | |
1761 | ||
d6392f87 | 1762 | fuse_inode_cachep = kmem_cache_create("fuse_inode", |
df206988 JW |
1763 | sizeof(struct fuse_inode), 0, |
1764 | SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT, | |
1765 | fuse_inode_init_once); | |
d6392f87 MS |
1766 | err = -ENOMEM; |
1767 | if (!fuse_inode_cachep) | |
988f0325 AV |
1768 | goto out; |
1769 | ||
1770 | err = register_fuseblk(); | |
1771 | if (err) | |
1772 | goto out2; | |
1773 | ||
1774 | err = register_filesystem(&fuse_fs_type); | |
1775 | if (err) | |
1776 | goto out3; | |
d6392f87 MS |
1777 | |
1778 | return 0; | |
d8a5ba45 | 1779 | |
988f0325 | 1780 | out3: |
875d95ec | 1781 | unregister_fuseblk(); |
988f0325 AV |
1782 | out2: |
1783 | kmem_cache_destroy(fuse_inode_cachep); | |
d6392f87 | 1784 | out: |
d8a5ba45 MS |
1785 | return err; |
1786 | } | |
1787 | ||
1788 | static void fuse_fs_cleanup(void) | |
1789 | { | |
1790 | unregister_filesystem(&fuse_fs_type); | |
875d95ec | 1791 | unregister_fuseblk(); |
8c0a8537 KS |
1792 | |
1793 | /* | |
1794 | * Make sure all delayed rcu free inodes are flushed before we | |
1795 | * destroy cache. | |
1796 | */ | |
1797 | rcu_barrier(); | |
d8a5ba45 MS |
1798 | kmem_cache_destroy(fuse_inode_cachep); |
1799 | } | |
1800 | ||
5c89e17e | 1801 | static struct kobject *fuse_kobj; |
5c89e17e | 1802 | |
f543f253 MS |
1803 | static int fuse_sysfs_init(void) |
1804 | { | |
1805 | int err; | |
1806 | ||
00d26666 | 1807 | fuse_kobj = kobject_create_and_add("fuse", fs_kobj); |
5c89e17e GKH |
1808 | if (!fuse_kobj) { |
1809 | err = -ENOMEM; | |
f543f253 | 1810 | goto out_err; |
5c89e17e | 1811 | } |
f543f253 | 1812 | |
f9bb4882 EB |
1813 | err = sysfs_create_mount_point(fuse_kobj, "connections"); |
1814 | if (err) | |
f543f253 MS |
1815 | goto out_fuse_unregister; |
1816 | ||
1817 | return 0; | |
1818 | ||
1819 | out_fuse_unregister: | |
197b12d6 | 1820 | kobject_put(fuse_kobj); |
f543f253 MS |
1821 | out_err: |
1822 | return err; | |
1823 | } | |
1824 | ||
1825 | static void fuse_sysfs_cleanup(void) | |
1826 | { | |
f9bb4882 | 1827 | sysfs_remove_mount_point(fuse_kobj, "connections"); |
197b12d6 | 1828 | kobject_put(fuse_kobj); |
f543f253 MS |
1829 | } |
1830 | ||
d8a5ba45 MS |
1831 | static int __init fuse_init(void) |
1832 | { | |
1833 | int res; | |
1834 | ||
f2294482 KS |
1835 | pr_info("init (API version %i.%i)\n", |
1836 | FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION); | |
d8a5ba45 | 1837 | |
bafa9654 | 1838 | INIT_LIST_HEAD(&fuse_conn_list); |
d8a5ba45 MS |
1839 | res = fuse_fs_init(); |
1840 | if (res) | |
1841 | goto err; | |
1842 | ||
334f485d MS |
1843 | res = fuse_dev_init(); |
1844 | if (res) | |
1845 | goto err_fs_cleanup; | |
1846 | ||
f543f253 MS |
1847 | res = fuse_sysfs_init(); |
1848 | if (res) | |
1849 | goto err_dev_cleanup; | |
1850 | ||
bafa9654 MS |
1851 | res = fuse_ctl_init(); |
1852 | if (res) | |
1853 | goto err_sysfs_cleanup; | |
1854 | ||
487ea5af CH |
1855 | sanitize_global_limit(&max_user_bgreq); |
1856 | sanitize_global_limit(&max_user_congthresh); | |
1857 | ||
d8a5ba45 MS |
1858 | return 0; |
1859 | ||
bafa9654 MS |
1860 | err_sysfs_cleanup: |
1861 | fuse_sysfs_cleanup(); | |
f543f253 MS |
1862 | err_dev_cleanup: |
1863 | fuse_dev_cleanup(); | |
334f485d MS |
1864 | err_fs_cleanup: |
1865 | fuse_fs_cleanup(); | |
d8a5ba45 MS |
1866 | err: |
1867 | return res; | |
1868 | } | |
1869 | ||
1870 | static void __exit fuse_exit(void) | |
1871 | { | |
f2294482 | 1872 | pr_debug("exit\n"); |
d8a5ba45 | 1873 | |
bafa9654 | 1874 | fuse_ctl_cleanup(); |
f543f253 | 1875 | fuse_sysfs_cleanup(); |
d8a5ba45 | 1876 | fuse_fs_cleanup(); |
334f485d | 1877 | fuse_dev_cleanup(); |
d8a5ba45 MS |
1878 | } |
1879 | ||
1880 | module_init(fuse_init); | |
1881 | module_exit(fuse_exit); |