| 1 | /* |
| 2 | FUSE: Filesystem in Userspace |
| 3 | Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu> |
| 4 | |
| 5 | This program can be distributed under the terms of the GNU GPL. |
| 6 | See the file COPYING. |
| 7 | */ |
| 8 | |
| 9 | #include "fuse_i.h" |
| 10 | |
| 11 | #include <linux/pagemap.h> |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/file.h> |
| 14 | #include <linux/seq_file.h> |
| 15 | #include <linux/init.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/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 | #include <uapi/linux/magic.h> |
| 27 | |
| 28 | MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); |
| 29 | MODULE_DESCRIPTION("Filesystem in Userspace"); |
| 30 | MODULE_LICENSE("GPL"); |
| 31 | |
| 32 | static struct kmem_cache *fuse_inode_cachep; |
| 33 | struct list_head fuse_conn_list; |
| 34 | DEFINE_MUTEX(fuse_mutex); |
| 35 | |
| 36 | static int set_global_limit(const char *val, const struct kernel_param *kp); |
| 37 | |
| 38 | unsigned max_user_bgreq; |
| 39 | module_param_call(max_user_bgreq, set_global_limit, param_get_uint, |
| 40 | &max_user_bgreq, 0644); |
| 41 | __MODULE_PARM_TYPE(max_user_bgreq, "uint"); |
| 42 | MODULE_PARM_DESC(max_user_bgreq, |
| 43 | "Global limit for the maximum number of backgrounded requests an " |
| 44 | "unprivileged user can set"); |
| 45 | |
| 46 | unsigned max_user_congthresh; |
| 47 | module_param_call(max_user_congthresh, set_global_limit, param_get_uint, |
| 48 | &max_user_congthresh, 0644); |
| 49 | __MODULE_PARM_TYPE(max_user_congthresh, "uint"); |
| 50 | MODULE_PARM_DESC(max_user_congthresh, |
| 51 | "Global limit for the maximum congestion threshold an " |
| 52 | "unprivileged user can set"); |
| 53 | |
| 54 | #define FUSE_DEFAULT_BLKSIZE 512 |
| 55 | |
| 56 | /** Maximum number of outstanding background requests */ |
| 57 | #define FUSE_DEFAULT_MAX_BACKGROUND 12 |
| 58 | |
| 59 | /** Congestion starts at 75% of maximum */ |
| 60 | #define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4) |
| 61 | |
| 62 | #ifdef CONFIG_BLOCK |
| 63 | static struct file_system_type fuseblk_fs_type; |
| 64 | #endif |
| 65 | |
| 66 | struct fuse_forget_link *fuse_alloc_forget(void) |
| 67 | { |
| 68 | return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL_ACCOUNT); |
| 69 | } |
| 70 | |
| 71 | static struct fuse_submount_lookup *fuse_alloc_submount_lookup(void) |
| 72 | { |
| 73 | struct fuse_submount_lookup *sl; |
| 74 | |
| 75 | sl = kzalloc(sizeof(struct fuse_submount_lookup), GFP_KERNEL_ACCOUNT); |
| 76 | if (!sl) |
| 77 | return NULL; |
| 78 | sl->forget = fuse_alloc_forget(); |
| 79 | if (!sl->forget) |
| 80 | goto out_free; |
| 81 | |
| 82 | return sl; |
| 83 | |
| 84 | out_free: |
| 85 | kfree(sl); |
| 86 | return NULL; |
| 87 | } |
| 88 | |
| 89 | static struct inode *fuse_alloc_inode(struct super_block *sb) |
| 90 | { |
| 91 | struct fuse_inode *fi; |
| 92 | |
| 93 | fi = alloc_inode_sb(sb, fuse_inode_cachep, GFP_KERNEL); |
| 94 | if (!fi) |
| 95 | return NULL; |
| 96 | |
| 97 | fi->i_time = 0; |
| 98 | fi->inval_mask = ~0; |
| 99 | fi->nodeid = 0; |
| 100 | fi->nlookup = 0; |
| 101 | fi->attr_version = 0; |
| 102 | fi->orig_ino = 0; |
| 103 | fi->state = 0; |
| 104 | fi->submount_lookup = NULL; |
| 105 | mutex_init(&fi->mutex); |
| 106 | spin_lock_init(&fi->lock); |
| 107 | fi->forget = fuse_alloc_forget(); |
| 108 | if (!fi->forget) |
| 109 | goto out_free; |
| 110 | |
| 111 | if (IS_ENABLED(CONFIG_FUSE_DAX) && !fuse_dax_inode_alloc(sb, fi)) |
| 112 | goto out_free_forget; |
| 113 | |
| 114 | if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) |
| 115 | fuse_inode_backing_set(fi, NULL); |
| 116 | |
| 117 | return &fi->inode; |
| 118 | |
| 119 | out_free_forget: |
| 120 | kfree(fi->forget); |
| 121 | out_free: |
| 122 | kmem_cache_free(fuse_inode_cachep, fi); |
| 123 | return NULL; |
| 124 | } |
| 125 | |
| 126 | static void fuse_free_inode(struct inode *inode) |
| 127 | { |
| 128 | struct fuse_inode *fi = get_fuse_inode(inode); |
| 129 | |
| 130 | mutex_destroy(&fi->mutex); |
| 131 | kfree(fi->forget); |
| 132 | #ifdef CONFIG_FUSE_DAX |
| 133 | kfree(fi->dax); |
| 134 | #endif |
| 135 | if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) |
| 136 | fuse_backing_put(fuse_inode_backing(fi)); |
| 137 | |
| 138 | kmem_cache_free(fuse_inode_cachep, fi); |
| 139 | } |
| 140 | |
| 141 | static void fuse_cleanup_submount_lookup(struct fuse_conn *fc, |
| 142 | struct fuse_submount_lookup *sl) |
| 143 | { |
| 144 | if (!refcount_dec_and_test(&sl->count)) |
| 145 | return; |
| 146 | |
| 147 | fuse_queue_forget(fc, sl->forget, sl->nodeid, 1); |
| 148 | sl->forget = NULL; |
| 149 | kfree(sl); |
| 150 | } |
| 151 | |
| 152 | static void fuse_evict_inode(struct inode *inode) |
| 153 | { |
| 154 | struct fuse_inode *fi = get_fuse_inode(inode); |
| 155 | |
| 156 | /* Will write inode on close/munmap and in all other dirtiers */ |
| 157 | WARN_ON(inode->i_state & I_DIRTY_INODE); |
| 158 | |
| 159 | truncate_inode_pages_final(&inode->i_data); |
| 160 | clear_inode(inode); |
| 161 | if (inode->i_sb->s_flags & SB_ACTIVE) { |
| 162 | struct fuse_conn *fc = get_fuse_conn(inode); |
| 163 | |
| 164 | if (FUSE_IS_DAX(inode)) |
| 165 | fuse_dax_inode_cleanup(inode); |
| 166 | if (fi->nlookup) { |
| 167 | fuse_queue_forget(fc, fi->forget, fi->nodeid, |
| 168 | fi->nlookup); |
| 169 | fi->forget = NULL; |
| 170 | } |
| 171 | |
| 172 | if (fi->submount_lookup) { |
| 173 | fuse_cleanup_submount_lookup(fc, fi->submount_lookup); |
| 174 | fi->submount_lookup = NULL; |
| 175 | } |
| 176 | } |
| 177 | if (S_ISREG(inode->i_mode) && !fuse_is_bad(inode)) { |
| 178 | WARN_ON(fi->iocachectr != 0); |
| 179 | WARN_ON(!list_empty(&fi->write_files)); |
| 180 | WARN_ON(!list_empty(&fi->queued_writes)); |
| 181 | } |
| 182 | } |
| 183 | |
| 184 | static int fuse_reconfigure(struct fs_context *fsc) |
| 185 | { |
| 186 | struct super_block *sb = fsc->root->d_sb; |
| 187 | |
| 188 | sync_filesystem(sb); |
| 189 | if (fsc->sb_flags & SB_MANDLOCK) |
| 190 | return -EINVAL; |
| 191 | |
| 192 | return 0; |
| 193 | } |
| 194 | |
| 195 | /* |
| 196 | * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down |
| 197 | * so that it will fit. |
| 198 | */ |
| 199 | static ino_t fuse_squash_ino(u64 ino64) |
| 200 | { |
| 201 | ino_t ino = (ino_t) ino64; |
| 202 | if (sizeof(ino_t) < sizeof(u64)) |
| 203 | ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8; |
| 204 | return ino; |
| 205 | } |
| 206 | |
| 207 | void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr, |
| 208 | struct fuse_statx *sx, |
| 209 | u64 attr_valid, u32 cache_mask) |
| 210 | { |
| 211 | struct fuse_conn *fc = get_fuse_conn(inode); |
| 212 | struct fuse_inode *fi = get_fuse_inode(inode); |
| 213 | |
| 214 | lockdep_assert_held(&fi->lock); |
| 215 | |
| 216 | fi->attr_version = atomic64_inc_return(&fc->attr_version); |
| 217 | fi->i_time = attr_valid; |
| 218 | /* Clear basic stats from invalid mask */ |
| 219 | set_mask_bits(&fi->inval_mask, STATX_BASIC_STATS, 0); |
| 220 | |
| 221 | inode->i_ino = fuse_squash_ino(attr->ino); |
| 222 | inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777); |
| 223 | set_nlink(inode, attr->nlink); |
| 224 | inode->i_uid = make_kuid(fc->user_ns, attr->uid); |
| 225 | inode->i_gid = make_kgid(fc->user_ns, attr->gid); |
| 226 | inode->i_blocks = attr->blocks; |
| 227 | |
| 228 | /* Sanitize nsecs */ |
| 229 | attr->atimensec = min_t(u32, attr->atimensec, NSEC_PER_SEC - 1); |
| 230 | attr->mtimensec = min_t(u32, attr->mtimensec, NSEC_PER_SEC - 1); |
| 231 | attr->ctimensec = min_t(u32, attr->ctimensec, NSEC_PER_SEC - 1); |
| 232 | |
| 233 | inode_set_atime(inode, attr->atime, attr->atimensec); |
| 234 | /* mtime from server may be stale due to local buffered write */ |
| 235 | if (!(cache_mask & STATX_MTIME)) { |
| 236 | inode_set_mtime(inode, attr->mtime, attr->mtimensec); |
| 237 | } |
| 238 | if (!(cache_mask & STATX_CTIME)) { |
| 239 | inode_set_ctime(inode, attr->ctime, attr->ctimensec); |
| 240 | } |
| 241 | if (sx) { |
| 242 | /* Sanitize nsecs */ |
| 243 | sx->btime.tv_nsec = |
| 244 | min_t(u32, sx->btime.tv_nsec, NSEC_PER_SEC - 1); |
| 245 | |
| 246 | /* |
| 247 | * Btime has been queried, cache is valid (whether or not btime |
| 248 | * is available or not) so clear STATX_BTIME from inval_mask. |
| 249 | * |
| 250 | * Availability of the btime attribute is indicated in |
| 251 | * FUSE_I_BTIME |
| 252 | */ |
| 253 | set_mask_bits(&fi->inval_mask, STATX_BTIME, 0); |
| 254 | if (sx->mask & STATX_BTIME) { |
| 255 | set_bit(FUSE_I_BTIME, &fi->state); |
| 256 | fi->i_btime.tv_sec = sx->btime.tv_sec; |
| 257 | fi->i_btime.tv_nsec = sx->btime.tv_nsec; |
| 258 | } |
| 259 | } |
| 260 | |
| 261 | if (attr->blksize != 0) |
| 262 | inode->i_blkbits = ilog2(attr->blksize); |
| 263 | else |
| 264 | inode->i_blkbits = inode->i_sb->s_blocksize_bits; |
| 265 | |
| 266 | /* |
| 267 | * Don't set the sticky bit in i_mode, unless we want the VFS |
| 268 | * to check permissions. This prevents failures due to the |
| 269 | * check in may_delete(). |
| 270 | */ |
| 271 | fi->orig_i_mode = inode->i_mode; |
| 272 | if (!fc->default_permissions) |
| 273 | inode->i_mode &= ~S_ISVTX; |
| 274 | |
| 275 | fi->orig_ino = attr->ino; |
| 276 | |
| 277 | /* |
| 278 | * We are refreshing inode data and it is possible that another |
| 279 | * client set suid/sgid or security.capability xattr. So clear |
| 280 | * S_NOSEC. Ideally, we could have cleared it only if suid/sgid |
| 281 | * was set or if security.capability xattr was set. But we don't |
| 282 | * know if security.capability has been set or not. So clear it |
| 283 | * anyway. Its less efficient but should be safe. |
| 284 | */ |
| 285 | inode->i_flags &= ~S_NOSEC; |
| 286 | } |
| 287 | |
| 288 | u32 fuse_get_cache_mask(struct inode *inode) |
| 289 | { |
| 290 | struct fuse_conn *fc = get_fuse_conn(inode); |
| 291 | |
| 292 | if (!fc->writeback_cache || !S_ISREG(inode->i_mode)) |
| 293 | return 0; |
| 294 | |
| 295 | return STATX_MTIME | STATX_CTIME | STATX_SIZE; |
| 296 | } |
| 297 | |
| 298 | void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr, |
| 299 | struct fuse_statx *sx, |
| 300 | u64 attr_valid, u64 attr_version) |
| 301 | { |
| 302 | struct fuse_conn *fc = get_fuse_conn(inode); |
| 303 | struct fuse_inode *fi = get_fuse_inode(inode); |
| 304 | u32 cache_mask; |
| 305 | loff_t oldsize; |
| 306 | struct timespec64 old_mtime; |
| 307 | |
| 308 | spin_lock(&fi->lock); |
| 309 | /* |
| 310 | * In case of writeback_cache enabled, writes update mtime, ctime and |
| 311 | * may update i_size. In these cases trust the cached value in the |
| 312 | * inode. |
| 313 | */ |
| 314 | cache_mask = fuse_get_cache_mask(inode); |
| 315 | if (cache_mask & STATX_SIZE) |
| 316 | attr->size = i_size_read(inode); |
| 317 | |
| 318 | if (cache_mask & STATX_MTIME) { |
| 319 | attr->mtime = inode_get_mtime_sec(inode); |
| 320 | attr->mtimensec = inode_get_mtime_nsec(inode); |
| 321 | } |
| 322 | if (cache_mask & STATX_CTIME) { |
| 323 | attr->ctime = inode_get_ctime_sec(inode); |
| 324 | attr->ctimensec = inode_get_ctime_nsec(inode); |
| 325 | } |
| 326 | |
| 327 | if ((attr_version != 0 && fi->attr_version > attr_version) || |
| 328 | test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) { |
| 329 | spin_unlock(&fi->lock); |
| 330 | return; |
| 331 | } |
| 332 | |
| 333 | old_mtime = inode_get_mtime(inode); |
| 334 | fuse_change_attributes_common(inode, attr, sx, attr_valid, cache_mask); |
| 335 | |
| 336 | oldsize = inode->i_size; |
| 337 | /* |
| 338 | * In case of writeback_cache enabled, the cached writes beyond EOF |
| 339 | * extend local i_size without keeping userspace server in sync. So, |
| 340 | * attr->size coming from server can be stale. We cannot trust it. |
| 341 | */ |
| 342 | if (!(cache_mask & STATX_SIZE)) |
| 343 | i_size_write(inode, attr->size); |
| 344 | spin_unlock(&fi->lock); |
| 345 | |
| 346 | if (!cache_mask && S_ISREG(inode->i_mode)) { |
| 347 | bool inval = false; |
| 348 | |
| 349 | if (oldsize != attr->size) { |
| 350 | truncate_pagecache(inode, attr->size); |
| 351 | if (!fc->explicit_inval_data) |
| 352 | inval = true; |
| 353 | } else if (fc->auto_inval_data) { |
| 354 | struct timespec64 new_mtime = { |
| 355 | .tv_sec = attr->mtime, |
| 356 | .tv_nsec = attr->mtimensec, |
| 357 | }; |
| 358 | |
| 359 | /* |
| 360 | * Auto inval mode also checks and invalidates if mtime |
| 361 | * has changed. |
| 362 | */ |
| 363 | if (!timespec64_equal(&old_mtime, &new_mtime)) |
| 364 | inval = true; |
| 365 | } |
| 366 | |
| 367 | if (inval) |
| 368 | invalidate_inode_pages2(inode->i_mapping); |
| 369 | } |
| 370 | |
| 371 | if (IS_ENABLED(CONFIG_FUSE_DAX)) |
| 372 | fuse_dax_dontcache(inode, attr->flags); |
| 373 | } |
| 374 | |
| 375 | static void fuse_init_submount_lookup(struct fuse_submount_lookup *sl, |
| 376 | u64 nodeid) |
| 377 | { |
| 378 | sl->nodeid = nodeid; |
| 379 | refcount_set(&sl->count, 1); |
| 380 | } |
| 381 | |
| 382 | static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr, |
| 383 | struct fuse_conn *fc) |
| 384 | { |
| 385 | inode->i_mode = attr->mode & S_IFMT; |
| 386 | inode->i_size = attr->size; |
| 387 | inode_set_mtime(inode, attr->mtime, attr->mtimensec); |
| 388 | inode_set_ctime(inode, attr->ctime, attr->ctimensec); |
| 389 | if (S_ISREG(inode->i_mode)) { |
| 390 | fuse_init_common(inode); |
| 391 | fuse_init_file_inode(inode, attr->flags); |
| 392 | } else if (S_ISDIR(inode->i_mode)) |
| 393 | fuse_init_dir(inode); |
| 394 | else if (S_ISLNK(inode->i_mode)) |
| 395 | fuse_init_symlink(inode); |
| 396 | else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || |
| 397 | S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { |
| 398 | fuse_init_common(inode); |
| 399 | init_special_inode(inode, inode->i_mode, |
| 400 | new_decode_dev(attr->rdev)); |
| 401 | } else |
| 402 | BUG(); |
| 403 | /* |
| 404 | * Ensure that we don't cache acls for daemons without FUSE_POSIX_ACL |
| 405 | * so they see the exact same behavior as before. |
| 406 | */ |
| 407 | if (!fc->posix_acl) |
| 408 | inode->i_acl = inode->i_default_acl = ACL_DONT_CACHE; |
| 409 | } |
| 410 | |
| 411 | static int fuse_inode_eq(struct inode *inode, void *_nodeidp) |
| 412 | { |
| 413 | u64 nodeid = *(u64 *) _nodeidp; |
| 414 | if (get_node_id(inode) == nodeid) |
| 415 | return 1; |
| 416 | else |
| 417 | return 0; |
| 418 | } |
| 419 | |
| 420 | static int fuse_inode_set(struct inode *inode, void *_nodeidp) |
| 421 | { |
| 422 | u64 nodeid = *(u64 *) _nodeidp; |
| 423 | get_fuse_inode(inode)->nodeid = nodeid; |
| 424 | return 0; |
| 425 | } |
| 426 | |
| 427 | struct inode *fuse_iget(struct super_block *sb, u64 nodeid, |
| 428 | int generation, struct fuse_attr *attr, |
| 429 | u64 attr_valid, u64 attr_version) |
| 430 | { |
| 431 | struct inode *inode; |
| 432 | struct fuse_inode *fi; |
| 433 | struct fuse_conn *fc = get_fuse_conn_super(sb); |
| 434 | |
| 435 | /* |
| 436 | * Auto mount points get their node id from the submount root, which is |
| 437 | * not a unique identifier within this filesystem. |
| 438 | * |
| 439 | * To avoid conflicts, do not place submount points into the inode hash |
| 440 | * table. |
| 441 | */ |
| 442 | if (fc->auto_submounts && (attr->flags & FUSE_ATTR_SUBMOUNT) && |
| 443 | S_ISDIR(attr->mode)) { |
| 444 | struct fuse_inode *fi; |
| 445 | |
| 446 | inode = new_inode(sb); |
| 447 | if (!inode) |
| 448 | return NULL; |
| 449 | |
| 450 | fuse_init_inode(inode, attr, fc); |
| 451 | fi = get_fuse_inode(inode); |
| 452 | fi->nodeid = nodeid; |
| 453 | fi->submount_lookup = fuse_alloc_submount_lookup(); |
| 454 | if (!fi->submount_lookup) { |
| 455 | iput(inode); |
| 456 | return NULL; |
| 457 | } |
| 458 | /* Sets nlookup = 1 on fi->submount_lookup->nlookup */ |
| 459 | fuse_init_submount_lookup(fi->submount_lookup, nodeid); |
| 460 | inode->i_flags |= S_AUTOMOUNT; |
| 461 | goto done; |
| 462 | } |
| 463 | |
| 464 | retry: |
| 465 | inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid); |
| 466 | if (!inode) |
| 467 | return NULL; |
| 468 | |
| 469 | if ((inode->i_state & I_NEW)) { |
| 470 | inode->i_flags |= S_NOATIME; |
| 471 | if (!fc->writeback_cache || !S_ISREG(attr->mode)) |
| 472 | inode->i_flags |= S_NOCMTIME; |
| 473 | inode->i_generation = generation; |
| 474 | fuse_init_inode(inode, attr, fc); |
| 475 | unlock_new_inode(inode); |
| 476 | } else if (fuse_stale_inode(inode, generation, attr)) { |
| 477 | /* nodeid was reused, any I/O on the old inode should fail */ |
| 478 | fuse_make_bad(inode); |
| 479 | if (inode != d_inode(sb->s_root)) { |
| 480 | remove_inode_hash(inode); |
| 481 | iput(inode); |
| 482 | goto retry; |
| 483 | } |
| 484 | } |
| 485 | fi = get_fuse_inode(inode); |
| 486 | spin_lock(&fi->lock); |
| 487 | fi->nlookup++; |
| 488 | spin_unlock(&fi->lock); |
| 489 | done: |
| 490 | fuse_change_attributes(inode, attr, NULL, attr_valid, attr_version); |
| 491 | |
| 492 | return inode; |
| 493 | } |
| 494 | |
| 495 | struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid, |
| 496 | struct fuse_mount **fm) |
| 497 | { |
| 498 | struct fuse_mount *fm_iter; |
| 499 | struct inode *inode; |
| 500 | |
| 501 | WARN_ON(!rwsem_is_locked(&fc->killsb)); |
| 502 | list_for_each_entry(fm_iter, &fc->mounts, fc_entry) { |
| 503 | if (!fm_iter->sb) |
| 504 | continue; |
| 505 | |
| 506 | inode = ilookup5(fm_iter->sb, nodeid, fuse_inode_eq, &nodeid); |
| 507 | if (inode) { |
| 508 | if (fm) |
| 509 | *fm = fm_iter; |
| 510 | return inode; |
| 511 | } |
| 512 | } |
| 513 | |
| 514 | return NULL; |
| 515 | } |
| 516 | |
| 517 | int fuse_reverse_inval_inode(struct fuse_conn *fc, u64 nodeid, |
| 518 | loff_t offset, loff_t len) |
| 519 | { |
| 520 | struct fuse_inode *fi; |
| 521 | struct inode *inode; |
| 522 | pgoff_t pg_start; |
| 523 | pgoff_t pg_end; |
| 524 | |
| 525 | inode = fuse_ilookup(fc, nodeid, NULL); |
| 526 | if (!inode) |
| 527 | return -ENOENT; |
| 528 | |
| 529 | fi = get_fuse_inode(inode); |
| 530 | spin_lock(&fi->lock); |
| 531 | fi->attr_version = atomic64_inc_return(&fc->attr_version); |
| 532 | spin_unlock(&fi->lock); |
| 533 | |
| 534 | fuse_invalidate_attr(inode); |
| 535 | forget_all_cached_acls(inode); |
| 536 | if (offset >= 0) { |
| 537 | pg_start = offset >> PAGE_SHIFT; |
| 538 | if (len <= 0) |
| 539 | pg_end = -1; |
| 540 | else |
| 541 | pg_end = (offset + len - 1) >> PAGE_SHIFT; |
| 542 | invalidate_inode_pages2_range(inode->i_mapping, |
| 543 | pg_start, pg_end); |
| 544 | } |
| 545 | iput(inode); |
| 546 | return 0; |
| 547 | } |
| 548 | |
| 549 | bool fuse_lock_inode(struct inode *inode) |
| 550 | { |
| 551 | bool locked = false; |
| 552 | |
| 553 | if (!get_fuse_conn(inode)->parallel_dirops) { |
| 554 | mutex_lock(&get_fuse_inode(inode)->mutex); |
| 555 | locked = true; |
| 556 | } |
| 557 | |
| 558 | return locked; |
| 559 | } |
| 560 | |
| 561 | void fuse_unlock_inode(struct inode *inode, bool locked) |
| 562 | { |
| 563 | if (locked) |
| 564 | mutex_unlock(&get_fuse_inode(inode)->mutex); |
| 565 | } |
| 566 | |
| 567 | static void fuse_umount_begin(struct super_block *sb) |
| 568 | { |
| 569 | struct fuse_conn *fc = get_fuse_conn_super(sb); |
| 570 | |
| 571 | if (fc->no_force_umount) |
| 572 | return; |
| 573 | |
| 574 | fuse_abort_conn(fc); |
| 575 | |
| 576 | // Only retire block-device-based superblocks. |
| 577 | if (sb->s_bdev != NULL) |
| 578 | retire_super(sb); |
| 579 | } |
| 580 | |
| 581 | static void fuse_send_destroy(struct fuse_mount *fm) |
| 582 | { |
| 583 | if (fm->fc->conn_init) { |
| 584 | FUSE_ARGS(args); |
| 585 | |
| 586 | args.opcode = FUSE_DESTROY; |
| 587 | args.force = true; |
| 588 | args.nocreds = true; |
| 589 | fuse_simple_request(fm, &args); |
| 590 | } |
| 591 | } |
| 592 | |
| 593 | static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr) |
| 594 | { |
| 595 | stbuf->f_type = FUSE_SUPER_MAGIC; |
| 596 | stbuf->f_bsize = attr->bsize; |
| 597 | stbuf->f_frsize = attr->frsize; |
| 598 | stbuf->f_blocks = attr->blocks; |
| 599 | stbuf->f_bfree = attr->bfree; |
| 600 | stbuf->f_bavail = attr->bavail; |
| 601 | stbuf->f_files = attr->files; |
| 602 | stbuf->f_ffree = attr->ffree; |
| 603 | stbuf->f_namelen = attr->namelen; |
| 604 | /* fsid is left zero */ |
| 605 | } |
| 606 | |
| 607 | static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf) |
| 608 | { |
| 609 | struct super_block *sb = dentry->d_sb; |
| 610 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
| 611 | FUSE_ARGS(args); |
| 612 | struct fuse_statfs_out outarg; |
| 613 | int err; |
| 614 | |
| 615 | if (!fuse_allow_current_process(fm->fc)) { |
| 616 | buf->f_type = FUSE_SUPER_MAGIC; |
| 617 | return 0; |
| 618 | } |
| 619 | |
| 620 | memset(&outarg, 0, sizeof(outarg)); |
| 621 | args.in_numargs = 0; |
| 622 | args.opcode = FUSE_STATFS; |
| 623 | args.nodeid = get_node_id(d_inode(dentry)); |
| 624 | args.out_numargs = 1; |
| 625 | args.out_args[0].size = sizeof(outarg); |
| 626 | args.out_args[0].value = &outarg; |
| 627 | err = fuse_simple_request(fm, &args); |
| 628 | if (!err) |
| 629 | convert_fuse_statfs(buf, &outarg.st); |
| 630 | return err; |
| 631 | } |
| 632 | |
| 633 | static struct fuse_sync_bucket *fuse_sync_bucket_alloc(void) |
| 634 | { |
| 635 | struct fuse_sync_bucket *bucket; |
| 636 | |
| 637 | bucket = kzalloc(sizeof(*bucket), GFP_KERNEL | __GFP_NOFAIL); |
| 638 | if (bucket) { |
| 639 | init_waitqueue_head(&bucket->waitq); |
| 640 | /* Initial active count */ |
| 641 | atomic_set(&bucket->count, 1); |
| 642 | } |
| 643 | return bucket; |
| 644 | } |
| 645 | |
| 646 | static void fuse_sync_fs_writes(struct fuse_conn *fc) |
| 647 | { |
| 648 | struct fuse_sync_bucket *bucket, *new_bucket; |
| 649 | int count; |
| 650 | |
| 651 | new_bucket = fuse_sync_bucket_alloc(); |
| 652 | spin_lock(&fc->lock); |
| 653 | bucket = rcu_dereference_protected(fc->curr_bucket, 1); |
| 654 | count = atomic_read(&bucket->count); |
| 655 | WARN_ON(count < 1); |
| 656 | /* No outstanding writes? */ |
| 657 | if (count == 1) { |
| 658 | spin_unlock(&fc->lock); |
| 659 | kfree(new_bucket); |
| 660 | return; |
| 661 | } |
| 662 | |
| 663 | /* |
| 664 | * Completion of new bucket depends on completion of this bucket, so add |
| 665 | * one more count. |
| 666 | */ |
| 667 | atomic_inc(&new_bucket->count); |
| 668 | rcu_assign_pointer(fc->curr_bucket, new_bucket); |
| 669 | spin_unlock(&fc->lock); |
| 670 | /* |
| 671 | * Drop initial active count. At this point if all writes in this and |
| 672 | * ancestor buckets complete, the count will go to zero and this task |
| 673 | * will be woken up. |
| 674 | */ |
| 675 | atomic_dec(&bucket->count); |
| 676 | |
| 677 | wait_event(bucket->waitq, atomic_read(&bucket->count) == 0); |
| 678 | |
| 679 | /* Drop temp count on descendant bucket */ |
| 680 | fuse_sync_bucket_dec(new_bucket); |
| 681 | kfree_rcu(bucket, rcu); |
| 682 | } |
| 683 | |
| 684 | static int fuse_sync_fs(struct super_block *sb, int wait) |
| 685 | { |
| 686 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
| 687 | struct fuse_conn *fc = fm->fc; |
| 688 | struct fuse_syncfs_in inarg; |
| 689 | FUSE_ARGS(args); |
| 690 | int err; |
| 691 | |
| 692 | /* |
| 693 | * Userspace cannot handle the wait == 0 case. Avoid a |
| 694 | * gratuitous roundtrip. |
| 695 | */ |
| 696 | if (!wait) |
| 697 | return 0; |
| 698 | |
| 699 | /* The filesystem is being unmounted. Nothing to do. */ |
| 700 | if (!sb->s_root) |
| 701 | return 0; |
| 702 | |
| 703 | if (!fc->sync_fs) |
| 704 | return 0; |
| 705 | |
| 706 | fuse_sync_fs_writes(fc); |
| 707 | |
| 708 | memset(&inarg, 0, sizeof(inarg)); |
| 709 | args.in_numargs = 1; |
| 710 | args.in_args[0].size = sizeof(inarg); |
| 711 | args.in_args[0].value = &inarg; |
| 712 | args.opcode = FUSE_SYNCFS; |
| 713 | args.nodeid = get_node_id(sb->s_root->d_inode); |
| 714 | args.out_numargs = 0; |
| 715 | |
| 716 | err = fuse_simple_request(fm, &args); |
| 717 | if (err == -ENOSYS) { |
| 718 | fc->sync_fs = 0; |
| 719 | err = 0; |
| 720 | } |
| 721 | |
| 722 | return err; |
| 723 | } |
| 724 | |
| 725 | enum { |
| 726 | OPT_SOURCE, |
| 727 | OPT_SUBTYPE, |
| 728 | OPT_FD, |
| 729 | OPT_ROOTMODE, |
| 730 | OPT_USER_ID, |
| 731 | OPT_GROUP_ID, |
| 732 | OPT_DEFAULT_PERMISSIONS, |
| 733 | OPT_ALLOW_OTHER, |
| 734 | OPT_MAX_READ, |
| 735 | OPT_BLKSIZE, |
| 736 | OPT_ERR |
| 737 | }; |
| 738 | |
| 739 | static const struct fs_parameter_spec fuse_fs_parameters[] = { |
| 740 | fsparam_string ("source", OPT_SOURCE), |
| 741 | fsparam_u32 ("fd", OPT_FD), |
| 742 | fsparam_u32oct ("rootmode", OPT_ROOTMODE), |
| 743 | fsparam_uid ("user_id", OPT_USER_ID), |
| 744 | fsparam_gid ("group_id", OPT_GROUP_ID), |
| 745 | fsparam_flag ("default_permissions", OPT_DEFAULT_PERMISSIONS), |
| 746 | fsparam_flag ("allow_other", OPT_ALLOW_OTHER), |
| 747 | fsparam_u32 ("max_read", OPT_MAX_READ), |
| 748 | fsparam_u32 ("blksize", OPT_BLKSIZE), |
| 749 | fsparam_string ("subtype", OPT_SUBTYPE), |
| 750 | {} |
| 751 | }; |
| 752 | |
| 753 | static int fuse_parse_param(struct fs_context *fsc, struct fs_parameter *param) |
| 754 | { |
| 755 | struct fs_parse_result result; |
| 756 | struct fuse_fs_context *ctx = fsc->fs_private; |
| 757 | int opt; |
| 758 | kuid_t kuid; |
| 759 | kgid_t kgid; |
| 760 | |
| 761 | if (fsc->purpose == FS_CONTEXT_FOR_RECONFIGURE) { |
| 762 | /* |
| 763 | * Ignore options coming from mount(MS_REMOUNT) for backward |
| 764 | * compatibility. |
| 765 | */ |
| 766 | if (fsc->oldapi) |
| 767 | return 0; |
| 768 | |
| 769 | return invalfc(fsc, "No changes allowed in reconfigure"); |
| 770 | } |
| 771 | |
| 772 | opt = fs_parse(fsc, fuse_fs_parameters, param, &result); |
| 773 | if (opt < 0) |
| 774 | return opt; |
| 775 | |
| 776 | switch (opt) { |
| 777 | case OPT_SOURCE: |
| 778 | if (fsc->source) |
| 779 | return invalfc(fsc, "Multiple sources specified"); |
| 780 | fsc->source = param->string; |
| 781 | param->string = NULL; |
| 782 | break; |
| 783 | |
| 784 | case OPT_SUBTYPE: |
| 785 | if (ctx->subtype) |
| 786 | return invalfc(fsc, "Multiple subtypes specified"); |
| 787 | ctx->subtype = param->string; |
| 788 | param->string = NULL; |
| 789 | return 0; |
| 790 | |
| 791 | case OPT_FD: |
| 792 | ctx->fd = result.uint_32; |
| 793 | ctx->fd_present = true; |
| 794 | break; |
| 795 | |
| 796 | case OPT_ROOTMODE: |
| 797 | if (!fuse_valid_type(result.uint_32)) |
| 798 | return invalfc(fsc, "Invalid rootmode"); |
| 799 | ctx->rootmode = result.uint_32; |
| 800 | ctx->rootmode_present = true; |
| 801 | break; |
| 802 | |
| 803 | case OPT_USER_ID: |
| 804 | kuid = result.uid; |
| 805 | /* |
| 806 | * The requested uid must be representable in the |
| 807 | * filesystem's idmapping. |
| 808 | */ |
| 809 | if (!kuid_has_mapping(fsc->user_ns, kuid)) |
| 810 | return invalfc(fsc, "Invalid user_id"); |
| 811 | ctx->user_id = kuid; |
| 812 | ctx->user_id_present = true; |
| 813 | break; |
| 814 | |
| 815 | case OPT_GROUP_ID: |
| 816 | kgid = result.gid; |
| 817 | /* |
| 818 | * The requested gid must be representable in the |
| 819 | * filesystem's idmapping. |
| 820 | */ |
| 821 | if (!kgid_has_mapping(fsc->user_ns, kgid)) |
| 822 | return invalfc(fsc, "Invalid group_id"); |
| 823 | ctx->group_id = kgid; |
| 824 | ctx->group_id_present = true; |
| 825 | break; |
| 826 | |
| 827 | case OPT_DEFAULT_PERMISSIONS: |
| 828 | ctx->default_permissions = true; |
| 829 | break; |
| 830 | |
| 831 | case OPT_ALLOW_OTHER: |
| 832 | ctx->allow_other = true; |
| 833 | break; |
| 834 | |
| 835 | case OPT_MAX_READ: |
| 836 | ctx->max_read = result.uint_32; |
| 837 | break; |
| 838 | |
| 839 | case OPT_BLKSIZE: |
| 840 | if (!ctx->is_bdev) |
| 841 | return invalfc(fsc, "blksize only supported for fuseblk"); |
| 842 | ctx->blksize = result.uint_32; |
| 843 | break; |
| 844 | |
| 845 | default: |
| 846 | return -EINVAL; |
| 847 | } |
| 848 | |
| 849 | return 0; |
| 850 | } |
| 851 | |
| 852 | static void fuse_free_fsc(struct fs_context *fsc) |
| 853 | { |
| 854 | struct fuse_fs_context *ctx = fsc->fs_private; |
| 855 | |
| 856 | if (ctx) { |
| 857 | kfree(ctx->subtype); |
| 858 | kfree(ctx); |
| 859 | } |
| 860 | } |
| 861 | |
| 862 | static int fuse_show_options(struct seq_file *m, struct dentry *root) |
| 863 | { |
| 864 | struct super_block *sb = root->d_sb; |
| 865 | struct fuse_conn *fc = get_fuse_conn_super(sb); |
| 866 | |
| 867 | if (fc->legacy_opts_show) { |
| 868 | seq_printf(m, ",user_id=%u", |
| 869 | from_kuid_munged(fc->user_ns, fc->user_id)); |
| 870 | seq_printf(m, ",group_id=%u", |
| 871 | from_kgid_munged(fc->user_ns, fc->group_id)); |
| 872 | if (fc->default_permissions) |
| 873 | seq_puts(m, ",default_permissions"); |
| 874 | if (fc->allow_other) |
| 875 | seq_puts(m, ",allow_other"); |
| 876 | if (fc->max_read != ~0) |
| 877 | seq_printf(m, ",max_read=%u", fc->max_read); |
| 878 | if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE) |
| 879 | seq_printf(m, ",blksize=%lu", sb->s_blocksize); |
| 880 | } |
| 881 | #ifdef CONFIG_FUSE_DAX |
| 882 | if (fc->dax_mode == FUSE_DAX_ALWAYS) |
| 883 | seq_puts(m, ",dax=always"); |
| 884 | else if (fc->dax_mode == FUSE_DAX_NEVER) |
| 885 | seq_puts(m, ",dax=never"); |
| 886 | else if (fc->dax_mode == FUSE_DAX_INODE_USER) |
| 887 | seq_puts(m, ",dax=inode"); |
| 888 | #endif |
| 889 | |
| 890 | return 0; |
| 891 | } |
| 892 | |
| 893 | static void fuse_iqueue_init(struct fuse_iqueue *fiq, |
| 894 | const struct fuse_iqueue_ops *ops, |
| 895 | void *priv) |
| 896 | { |
| 897 | memset(fiq, 0, sizeof(struct fuse_iqueue)); |
| 898 | spin_lock_init(&fiq->lock); |
| 899 | init_waitqueue_head(&fiq->waitq); |
| 900 | INIT_LIST_HEAD(&fiq->pending); |
| 901 | INIT_LIST_HEAD(&fiq->interrupts); |
| 902 | fiq->forget_list_tail = &fiq->forget_list_head; |
| 903 | fiq->connected = 1; |
| 904 | fiq->ops = ops; |
| 905 | fiq->priv = priv; |
| 906 | } |
| 907 | |
| 908 | static void fuse_pqueue_init(struct fuse_pqueue *fpq) |
| 909 | { |
| 910 | unsigned int i; |
| 911 | |
| 912 | spin_lock_init(&fpq->lock); |
| 913 | for (i = 0; i < FUSE_PQ_HASH_SIZE; i++) |
| 914 | INIT_LIST_HEAD(&fpq->processing[i]); |
| 915 | INIT_LIST_HEAD(&fpq->io); |
| 916 | fpq->connected = 1; |
| 917 | } |
| 918 | |
| 919 | void fuse_conn_init(struct fuse_conn *fc, struct fuse_mount *fm, |
| 920 | struct user_namespace *user_ns, |
| 921 | const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv) |
| 922 | { |
| 923 | memset(fc, 0, sizeof(*fc)); |
| 924 | spin_lock_init(&fc->lock); |
| 925 | spin_lock_init(&fc->bg_lock); |
| 926 | init_rwsem(&fc->killsb); |
| 927 | refcount_set(&fc->count, 1); |
| 928 | atomic_set(&fc->dev_count, 1); |
| 929 | init_waitqueue_head(&fc->blocked_waitq); |
| 930 | fuse_iqueue_init(&fc->iq, fiq_ops, fiq_priv); |
| 931 | INIT_LIST_HEAD(&fc->bg_queue); |
| 932 | INIT_LIST_HEAD(&fc->entry); |
| 933 | INIT_LIST_HEAD(&fc->devices); |
| 934 | atomic_set(&fc->num_waiting, 0); |
| 935 | fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND; |
| 936 | fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD; |
| 937 | atomic64_set(&fc->khctr, 0); |
| 938 | fc->polled_files = RB_ROOT; |
| 939 | fc->blocked = 0; |
| 940 | fc->initialized = 0; |
| 941 | fc->connected = 1; |
| 942 | atomic64_set(&fc->attr_version, 1); |
| 943 | get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key)); |
| 944 | fc->pid_ns = get_pid_ns(task_active_pid_ns(current)); |
| 945 | fc->user_ns = get_user_ns(user_ns); |
| 946 | fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ; |
| 947 | fc->max_pages_limit = FUSE_MAX_MAX_PAGES; |
| 948 | |
| 949 | if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) |
| 950 | fuse_backing_files_init(fc); |
| 951 | |
| 952 | INIT_LIST_HEAD(&fc->mounts); |
| 953 | list_add(&fm->fc_entry, &fc->mounts); |
| 954 | fm->fc = fc; |
| 955 | } |
| 956 | EXPORT_SYMBOL_GPL(fuse_conn_init); |
| 957 | |
| 958 | static void delayed_release(struct rcu_head *p) |
| 959 | { |
| 960 | struct fuse_conn *fc = container_of(p, struct fuse_conn, rcu); |
| 961 | |
| 962 | put_user_ns(fc->user_ns); |
| 963 | fc->release(fc); |
| 964 | } |
| 965 | |
| 966 | void fuse_conn_put(struct fuse_conn *fc) |
| 967 | { |
| 968 | if (refcount_dec_and_test(&fc->count)) { |
| 969 | struct fuse_iqueue *fiq = &fc->iq; |
| 970 | struct fuse_sync_bucket *bucket; |
| 971 | |
| 972 | if (IS_ENABLED(CONFIG_FUSE_DAX)) |
| 973 | fuse_dax_conn_free(fc); |
| 974 | if (fiq->ops->release) |
| 975 | fiq->ops->release(fiq); |
| 976 | put_pid_ns(fc->pid_ns); |
| 977 | bucket = rcu_dereference_protected(fc->curr_bucket, 1); |
| 978 | if (bucket) { |
| 979 | WARN_ON(atomic_read(&bucket->count) != 1); |
| 980 | kfree(bucket); |
| 981 | } |
| 982 | if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) |
| 983 | fuse_backing_files_free(fc); |
| 984 | call_rcu(&fc->rcu, delayed_release); |
| 985 | } |
| 986 | } |
| 987 | EXPORT_SYMBOL_GPL(fuse_conn_put); |
| 988 | |
| 989 | struct fuse_conn *fuse_conn_get(struct fuse_conn *fc) |
| 990 | { |
| 991 | refcount_inc(&fc->count); |
| 992 | return fc; |
| 993 | } |
| 994 | EXPORT_SYMBOL_GPL(fuse_conn_get); |
| 995 | |
| 996 | static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode) |
| 997 | { |
| 998 | struct fuse_attr attr; |
| 999 | memset(&attr, 0, sizeof(attr)); |
| 1000 | |
| 1001 | attr.mode = mode; |
| 1002 | attr.ino = FUSE_ROOT_ID; |
| 1003 | attr.nlink = 1; |
| 1004 | return fuse_iget(sb, FUSE_ROOT_ID, 0, &attr, 0, 0); |
| 1005 | } |
| 1006 | |
| 1007 | struct fuse_inode_handle { |
| 1008 | u64 nodeid; |
| 1009 | u32 generation; |
| 1010 | }; |
| 1011 | |
| 1012 | static struct dentry *fuse_get_dentry(struct super_block *sb, |
| 1013 | struct fuse_inode_handle *handle) |
| 1014 | { |
| 1015 | struct fuse_conn *fc = get_fuse_conn_super(sb); |
| 1016 | struct inode *inode; |
| 1017 | struct dentry *entry; |
| 1018 | int err = -ESTALE; |
| 1019 | |
| 1020 | if (handle->nodeid == 0) |
| 1021 | goto out_err; |
| 1022 | |
| 1023 | inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid); |
| 1024 | if (!inode) { |
| 1025 | struct fuse_entry_out outarg; |
| 1026 | const struct qstr name = QSTR_INIT(".", 1); |
| 1027 | |
| 1028 | if (!fc->export_support) |
| 1029 | goto out_err; |
| 1030 | |
| 1031 | err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg, |
| 1032 | &inode); |
| 1033 | if (err && err != -ENOENT) |
| 1034 | goto out_err; |
| 1035 | if (err || !inode) { |
| 1036 | err = -ESTALE; |
| 1037 | goto out_err; |
| 1038 | } |
| 1039 | err = -EIO; |
| 1040 | if (get_node_id(inode) != handle->nodeid) |
| 1041 | goto out_iput; |
| 1042 | } |
| 1043 | err = -ESTALE; |
| 1044 | if (inode->i_generation != handle->generation) |
| 1045 | goto out_iput; |
| 1046 | |
| 1047 | entry = d_obtain_alias(inode); |
| 1048 | if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID) |
| 1049 | fuse_invalidate_entry_cache(entry); |
| 1050 | |
| 1051 | return entry; |
| 1052 | |
| 1053 | out_iput: |
| 1054 | iput(inode); |
| 1055 | out_err: |
| 1056 | return ERR_PTR(err); |
| 1057 | } |
| 1058 | |
| 1059 | static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len, |
| 1060 | struct inode *parent) |
| 1061 | { |
| 1062 | int len = parent ? 6 : 3; |
| 1063 | u64 nodeid; |
| 1064 | u32 generation; |
| 1065 | |
| 1066 | if (*max_len < len) { |
| 1067 | *max_len = len; |
| 1068 | return FILEID_INVALID; |
| 1069 | } |
| 1070 | |
| 1071 | nodeid = get_fuse_inode(inode)->nodeid; |
| 1072 | generation = inode->i_generation; |
| 1073 | |
| 1074 | fh[0] = (u32)(nodeid >> 32); |
| 1075 | fh[1] = (u32)(nodeid & 0xffffffff); |
| 1076 | fh[2] = generation; |
| 1077 | |
| 1078 | if (parent) { |
| 1079 | nodeid = get_fuse_inode(parent)->nodeid; |
| 1080 | generation = parent->i_generation; |
| 1081 | |
| 1082 | fh[3] = (u32)(nodeid >> 32); |
| 1083 | fh[4] = (u32)(nodeid & 0xffffffff); |
| 1084 | fh[5] = generation; |
| 1085 | } |
| 1086 | |
| 1087 | *max_len = len; |
| 1088 | return parent ? FILEID_INO64_GEN_PARENT : FILEID_INO64_GEN; |
| 1089 | } |
| 1090 | |
| 1091 | static struct dentry *fuse_fh_to_dentry(struct super_block *sb, |
| 1092 | struct fid *fid, int fh_len, int fh_type) |
| 1093 | { |
| 1094 | struct fuse_inode_handle handle; |
| 1095 | |
| 1096 | if ((fh_type != FILEID_INO64_GEN && |
| 1097 | fh_type != FILEID_INO64_GEN_PARENT) || fh_len < 3) |
| 1098 | return NULL; |
| 1099 | |
| 1100 | handle.nodeid = (u64) fid->raw[0] << 32; |
| 1101 | handle.nodeid |= (u64) fid->raw[1]; |
| 1102 | handle.generation = fid->raw[2]; |
| 1103 | return fuse_get_dentry(sb, &handle); |
| 1104 | } |
| 1105 | |
| 1106 | static struct dentry *fuse_fh_to_parent(struct super_block *sb, |
| 1107 | struct fid *fid, int fh_len, int fh_type) |
| 1108 | { |
| 1109 | struct fuse_inode_handle parent; |
| 1110 | |
| 1111 | if (fh_type != FILEID_INO64_GEN_PARENT || fh_len < 6) |
| 1112 | return NULL; |
| 1113 | |
| 1114 | parent.nodeid = (u64) fid->raw[3] << 32; |
| 1115 | parent.nodeid |= (u64) fid->raw[4]; |
| 1116 | parent.generation = fid->raw[5]; |
| 1117 | return fuse_get_dentry(sb, &parent); |
| 1118 | } |
| 1119 | |
| 1120 | static struct dentry *fuse_get_parent(struct dentry *child) |
| 1121 | { |
| 1122 | struct inode *child_inode = d_inode(child); |
| 1123 | struct fuse_conn *fc = get_fuse_conn(child_inode); |
| 1124 | struct inode *inode; |
| 1125 | struct dentry *parent; |
| 1126 | struct fuse_entry_out outarg; |
| 1127 | int err; |
| 1128 | |
| 1129 | if (!fc->export_support) |
| 1130 | return ERR_PTR(-ESTALE); |
| 1131 | |
| 1132 | err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode), |
| 1133 | &dotdot_name, &outarg, &inode); |
| 1134 | if (err) { |
| 1135 | if (err == -ENOENT) |
| 1136 | return ERR_PTR(-ESTALE); |
| 1137 | return ERR_PTR(err); |
| 1138 | } |
| 1139 | |
| 1140 | parent = d_obtain_alias(inode); |
| 1141 | if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID) |
| 1142 | fuse_invalidate_entry_cache(parent); |
| 1143 | |
| 1144 | return parent; |
| 1145 | } |
| 1146 | |
| 1147 | /* only for fid encoding; no support for file handle */ |
| 1148 | static const struct export_operations fuse_export_fid_operations = { |
| 1149 | .encode_fh = fuse_encode_fh, |
| 1150 | }; |
| 1151 | |
| 1152 | static const struct export_operations fuse_export_operations = { |
| 1153 | .fh_to_dentry = fuse_fh_to_dentry, |
| 1154 | .fh_to_parent = fuse_fh_to_parent, |
| 1155 | .encode_fh = fuse_encode_fh, |
| 1156 | .get_parent = fuse_get_parent, |
| 1157 | }; |
| 1158 | |
| 1159 | static const struct super_operations fuse_super_operations = { |
| 1160 | .alloc_inode = fuse_alloc_inode, |
| 1161 | .free_inode = fuse_free_inode, |
| 1162 | .evict_inode = fuse_evict_inode, |
| 1163 | .write_inode = fuse_write_inode, |
| 1164 | .drop_inode = generic_delete_inode, |
| 1165 | .umount_begin = fuse_umount_begin, |
| 1166 | .statfs = fuse_statfs, |
| 1167 | .sync_fs = fuse_sync_fs, |
| 1168 | .show_options = fuse_show_options, |
| 1169 | }; |
| 1170 | |
| 1171 | static void sanitize_global_limit(unsigned *limit) |
| 1172 | { |
| 1173 | /* |
| 1174 | * The default maximum number of async requests is calculated to consume |
| 1175 | * 1/2^13 of the total memory, assuming 392 bytes per request. |
| 1176 | */ |
| 1177 | if (*limit == 0) |
| 1178 | *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 392; |
| 1179 | |
| 1180 | if (*limit >= 1 << 16) |
| 1181 | *limit = (1 << 16) - 1; |
| 1182 | } |
| 1183 | |
| 1184 | static int set_global_limit(const char *val, const struct kernel_param *kp) |
| 1185 | { |
| 1186 | int rv; |
| 1187 | |
| 1188 | rv = param_set_uint(val, kp); |
| 1189 | if (rv) |
| 1190 | return rv; |
| 1191 | |
| 1192 | sanitize_global_limit((unsigned *)kp->arg); |
| 1193 | |
| 1194 | return 0; |
| 1195 | } |
| 1196 | |
| 1197 | static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg) |
| 1198 | { |
| 1199 | int cap_sys_admin = capable(CAP_SYS_ADMIN); |
| 1200 | |
| 1201 | if (arg->minor < 13) |
| 1202 | return; |
| 1203 | |
| 1204 | sanitize_global_limit(&max_user_bgreq); |
| 1205 | sanitize_global_limit(&max_user_congthresh); |
| 1206 | |
| 1207 | spin_lock(&fc->bg_lock); |
| 1208 | if (arg->max_background) { |
| 1209 | fc->max_background = arg->max_background; |
| 1210 | |
| 1211 | if (!cap_sys_admin && fc->max_background > max_user_bgreq) |
| 1212 | fc->max_background = max_user_bgreq; |
| 1213 | } |
| 1214 | if (arg->congestion_threshold) { |
| 1215 | fc->congestion_threshold = arg->congestion_threshold; |
| 1216 | |
| 1217 | if (!cap_sys_admin && |
| 1218 | fc->congestion_threshold > max_user_congthresh) |
| 1219 | fc->congestion_threshold = max_user_congthresh; |
| 1220 | } |
| 1221 | spin_unlock(&fc->bg_lock); |
| 1222 | } |
| 1223 | |
| 1224 | struct fuse_init_args { |
| 1225 | struct fuse_args args; |
| 1226 | struct fuse_init_in in; |
| 1227 | struct fuse_init_out out; |
| 1228 | }; |
| 1229 | |
| 1230 | static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args, |
| 1231 | int error) |
| 1232 | { |
| 1233 | struct fuse_conn *fc = fm->fc; |
| 1234 | struct fuse_init_args *ia = container_of(args, typeof(*ia), args); |
| 1235 | struct fuse_init_out *arg = &ia->out; |
| 1236 | bool ok = true; |
| 1237 | |
| 1238 | if (error || arg->major != FUSE_KERNEL_VERSION) |
| 1239 | ok = false; |
| 1240 | else { |
| 1241 | unsigned long ra_pages; |
| 1242 | |
| 1243 | process_init_limits(fc, arg); |
| 1244 | |
| 1245 | if (arg->minor >= 6) { |
| 1246 | u64 flags = arg->flags; |
| 1247 | |
| 1248 | if (flags & FUSE_INIT_EXT) |
| 1249 | flags |= (u64) arg->flags2 << 32; |
| 1250 | |
| 1251 | ra_pages = arg->max_readahead / PAGE_SIZE; |
| 1252 | if (flags & FUSE_ASYNC_READ) |
| 1253 | fc->async_read = 1; |
| 1254 | if (!(flags & FUSE_POSIX_LOCKS)) |
| 1255 | fc->no_lock = 1; |
| 1256 | if (arg->minor >= 17) { |
| 1257 | if (!(flags & FUSE_FLOCK_LOCKS)) |
| 1258 | fc->no_flock = 1; |
| 1259 | } else { |
| 1260 | if (!(flags & FUSE_POSIX_LOCKS)) |
| 1261 | fc->no_flock = 1; |
| 1262 | } |
| 1263 | if (flags & FUSE_ATOMIC_O_TRUNC) |
| 1264 | fc->atomic_o_trunc = 1; |
| 1265 | if (arg->minor >= 9) { |
| 1266 | /* LOOKUP has dependency on proto version */ |
| 1267 | if (flags & FUSE_EXPORT_SUPPORT) |
| 1268 | fc->export_support = 1; |
| 1269 | } |
| 1270 | if (flags & FUSE_BIG_WRITES) |
| 1271 | fc->big_writes = 1; |
| 1272 | if (flags & FUSE_DONT_MASK) |
| 1273 | fc->dont_mask = 1; |
| 1274 | if (flags & FUSE_AUTO_INVAL_DATA) |
| 1275 | fc->auto_inval_data = 1; |
| 1276 | else if (flags & FUSE_EXPLICIT_INVAL_DATA) |
| 1277 | fc->explicit_inval_data = 1; |
| 1278 | if (flags & FUSE_DO_READDIRPLUS) { |
| 1279 | fc->do_readdirplus = 1; |
| 1280 | if (flags & FUSE_READDIRPLUS_AUTO) |
| 1281 | fc->readdirplus_auto = 1; |
| 1282 | } |
| 1283 | if (flags & FUSE_ASYNC_DIO) |
| 1284 | fc->async_dio = 1; |
| 1285 | if (flags & FUSE_WRITEBACK_CACHE) |
| 1286 | fc->writeback_cache = 1; |
| 1287 | if (flags & FUSE_PARALLEL_DIROPS) |
| 1288 | fc->parallel_dirops = 1; |
| 1289 | if (flags & FUSE_HANDLE_KILLPRIV) |
| 1290 | fc->handle_killpriv = 1; |
| 1291 | if (arg->time_gran && arg->time_gran <= 1000000000) |
| 1292 | fm->sb->s_time_gran = arg->time_gran; |
| 1293 | if ((flags & FUSE_POSIX_ACL)) { |
| 1294 | fc->default_permissions = 1; |
| 1295 | fc->posix_acl = 1; |
| 1296 | } |
| 1297 | if (flags & FUSE_CACHE_SYMLINKS) |
| 1298 | fc->cache_symlinks = 1; |
| 1299 | if (flags & FUSE_ABORT_ERROR) |
| 1300 | fc->abort_err = 1; |
| 1301 | if (flags & FUSE_MAX_PAGES) { |
| 1302 | fc->max_pages = |
| 1303 | min_t(unsigned int, fc->max_pages_limit, |
| 1304 | max_t(unsigned int, arg->max_pages, 1)); |
| 1305 | } |
| 1306 | if (IS_ENABLED(CONFIG_FUSE_DAX)) { |
| 1307 | if (flags & FUSE_MAP_ALIGNMENT && |
| 1308 | !fuse_dax_check_alignment(fc, arg->map_alignment)) { |
| 1309 | ok = false; |
| 1310 | } |
| 1311 | if (flags & FUSE_HAS_INODE_DAX) |
| 1312 | fc->inode_dax = 1; |
| 1313 | } |
| 1314 | if (flags & FUSE_HANDLE_KILLPRIV_V2) { |
| 1315 | fc->handle_killpriv_v2 = 1; |
| 1316 | fm->sb->s_flags |= SB_NOSEC; |
| 1317 | } |
| 1318 | if (flags & FUSE_SETXATTR_EXT) |
| 1319 | fc->setxattr_ext = 1; |
| 1320 | if (flags & FUSE_SECURITY_CTX) |
| 1321 | fc->init_security = 1; |
| 1322 | if (flags & FUSE_CREATE_SUPP_GROUP) |
| 1323 | fc->create_supp_group = 1; |
| 1324 | if (flags & FUSE_DIRECT_IO_ALLOW_MMAP) |
| 1325 | fc->direct_io_allow_mmap = 1; |
| 1326 | /* |
| 1327 | * max_stack_depth is the max stack depth of FUSE fs, |
| 1328 | * so it has to be at least 1 to support passthrough |
| 1329 | * to backing files. |
| 1330 | * |
| 1331 | * with max_stack_depth > 1, the backing files can be |
| 1332 | * on a stacked fs (e.g. overlayfs) themselves and with |
| 1333 | * max_stack_depth == 1, FUSE fs can be stacked as the |
| 1334 | * underlying fs of a stacked fs (e.g. overlayfs). |
| 1335 | * |
| 1336 | * Also don't allow the combination of FUSE_PASSTHROUGH |
| 1337 | * and FUSE_WRITEBACK_CACHE, current design doesn't handle |
| 1338 | * them together. |
| 1339 | */ |
| 1340 | if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH) && |
| 1341 | (flags & FUSE_PASSTHROUGH) && |
| 1342 | arg->max_stack_depth > 0 && |
| 1343 | arg->max_stack_depth <= FILESYSTEM_MAX_STACK_DEPTH && |
| 1344 | !(flags & FUSE_WRITEBACK_CACHE)) { |
| 1345 | fc->passthrough = 1; |
| 1346 | fc->max_stack_depth = arg->max_stack_depth; |
| 1347 | fm->sb->s_stack_depth = arg->max_stack_depth; |
| 1348 | } |
| 1349 | if (flags & FUSE_NO_EXPORT_SUPPORT) |
| 1350 | fm->sb->s_export_op = &fuse_export_fid_operations; |
| 1351 | if (flags & FUSE_ALLOW_IDMAP) { |
| 1352 | if (fc->default_permissions) |
| 1353 | fm->sb->s_iflags &= ~SB_I_NOIDMAP; |
| 1354 | else |
| 1355 | ok = false; |
| 1356 | } |
| 1357 | } else { |
| 1358 | ra_pages = fc->max_read / PAGE_SIZE; |
| 1359 | fc->no_lock = 1; |
| 1360 | fc->no_flock = 1; |
| 1361 | } |
| 1362 | |
| 1363 | fm->sb->s_bdi->ra_pages = |
| 1364 | min(fm->sb->s_bdi->ra_pages, ra_pages); |
| 1365 | fc->minor = arg->minor; |
| 1366 | fc->max_write = arg->minor < 5 ? 4096 : arg->max_write; |
| 1367 | fc->max_write = max_t(unsigned, 4096, fc->max_write); |
| 1368 | fc->conn_init = 1; |
| 1369 | } |
| 1370 | kfree(ia); |
| 1371 | |
| 1372 | if (!ok) { |
| 1373 | fc->conn_init = 0; |
| 1374 | fc->conn_error = 1; |
| 1375 | } |
| 1376 | |
| 1377 | fuse_set_initialized(fc); |
| 1378 | wake_up_all(&fc->blocked_waitq); |
| 1379 | } |
| 1380 | |
| 1381 | void fuse_send_init(struct fuse_mount *fm) |
| 1382 | { |
| 1383 | struct fuse_init_args *ia; |
| 1384 | u64 flags; |
| 1385 | |
| 1386 | ia = kzalloc(sizeof(*ia), GFP_KERNEL | __GFP_NOFAIL); |
| 1387 | |
| 1388 | ia->in.major = FUSE_KERNEL_VERSION; |
| 1389 | ia->in.minor = FUSE_KERNEL_MINOR_VERSION; |
| 1390 | ia->in.max_readahead = fm->sb->s_bdi->ra_pages * PAGE_SIZE; |
| 1391 | flags = |
| 1392 | FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC | |
| 1393 | FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK | |
| 1394 | FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ | |
| 1395 | FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA | |
| 1396 | FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO | |
| 1397 | FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT | |
| 1398 | FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL | |
| 1399 | FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS | |
| 1400 | FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA | |
| 1401 | FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT | FUSE_INIT_EXT | |
| 1402 | FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP | |
| 1403 | FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_ALLOW_MMAP | |
| 1404 | FUSE_NO_EXPORT_SUPPORT | FUSE_HAS_RESEND | FUSE_ALLOW_IDMAP; |
| 1405 | #ifdef CONFIG_FUSE_DAX |
| 1406 | if (fm->fc->dax) |
| 1407 | flags |= FUSE_MAP_ALIGNMENT; |
| 1408 | if (fuse_is_inode_dax_mode(fm->fc->dax_mode)) |
| 1409 | flags |= FUSE_HAS_INODE_DAX; |
| 1410 | #endif |
| 1411 | if (fm->fc->auto_submounts) |
| 1412 | flags |= FUSE_SUBMOUNTS; |
| 1413 | if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) |
| 1414 | flags |= FUSE_PASSTHROUGH; |
| 1415 | |
| 1416 | ia->in.flags = flags; |
| 1417 | ia->in.flags2 = flags >> 32; |
| 1418 | |
| 1419 | ia->args.opcode = FUSE_INIT; |
| 1420 | ia->args.in_numargs = 1; |
| 1421 | ia->args.in_args[0].size = sizeof(ia->in); |
| 1422 | ia->args.in_args[0].value = &ia->in; |
| 1423 | ia->args.out_numargs = 1; |
| 1424 | /* Variable length argument used for backward compatibility |
| 1425 | with interface version < 7.5. Rest of init_out is zeroed |
| 1426 | by do_get_request(), so a short reply is not a problem */ |
| 1427 | ia->args.out_argvar = true; |
| 1428 | ia->args.out_args[0].size = sizeof(ia->out); |
| 1429 | ia->args.out_args[0].value = &ia->out; |
| 1430 | ia->args.force = true; |
| 1431 | ia->args.nocreds = true; |
| 1432 | ia->args.end = process_init_reply; |
| 1433 | |
| 1434 | if (fuse_simple_background(fm, &ia->args, GFP_KERNEL) != 0) |
| 1435 | process_init_reply(fm, &ia->args, -ENOTCONN); |
| 1436 | } |
| 1437 | EXPORT_SYMBOL_GPL(fuse_send_init); |
| 1438 | |
| 1439 | void fuse_free_conn(struct fuse_conn *fc) |
| 1440 | { |
| 1441 | WARN_ON(!list_empty(&fc->devices)); |
| 1442 | kfree(fc); |
| 1443 | } |
| 1444 | EXPORT_SYMBOL_GPL(fuse_free_conn); |
| 1445 | |
| 1446 | static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb) |
| 1447 | { |
| 1448 | int err; |
| 1449 | char *suffix = ""; |
| 1450 | |
| 1451 | if (sb->s_bdev) { |
| 1452 | suffix = "-fuseblk"; |
| 1453 | /* |
| 1454 | * sb->s_bdi points to blkdev's bdi however we want to redirect |
| 1455 | * it to our private bdi... |
| 1456 | */ |
| 1457 | bdi_put(sb->s_bdi); |
| 1458 | sb->s_bdi = &noop_backing_dev_info; |
| 1459 | } |
| 1460 | err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev), |
| 1461 | MINOR(fc->dev), suffix); |
| 1462 | if (err) |
| 1463 | return err; |
| 1464 | |
| 1465 | /* fuse does it's own writeback accounting */ |
| 1466 | sb->s_bdi->capabilities &= ~BDI_CAP_WRITEBACK_ACCT; |
| 1467 | sb->s_bdi->capabilities |= BDI_CAP_STRICTLIMIT; |
| 1468 | |
| 1469 | /* |
| 1470 | * For a single fuse filesystem use max 1% of dirty + |
| 1471 | * writeback threshold. |
| 1472 | * |
| 1473 | * This gives about 1M of write buffer for memory maps on a |
| 1474 | * machine with 1G and 10% dirty_ratio, which should be more |
| 1475 | * than enough. |
| 1476 | * |
| 1477 | * Privileged users can raise it by writing to |
| 1478 | * |
| 1479 | * /sys/class/bdi/<bdi>/max_ratio |
| 1480 | */ |
| 1481 | bdi_set_max_ratio(sb->s_bdi, 1); |
| 1482 | |
| 1483 | return 0; |
| 1484 | } |
| 1485 | |
| 1486 | struct fuse_dev *fuse_dev_alloc(void) |
| 1487 | { |
| 1488 | struct fuse_dev *fud; |
| 1489 | struct list_head *pq; |
| 1490 | |
| 1491 | fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL); |
| 1492 | if (!fud) |
| 1493 | return NULL; |
| 1494 | |
| 1495 | pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL); |
| 1496 | if (!pq) { |
| 1497 | kfree(fud); |
| 1498 | return NULL; |
| 1499 | } |
| 1500 | |
| 1501 | fud->pq.processing = pq; |
| 1502 | fuse_pqueue_init(&fud->pq); |
| 1503 | |
| 1504 | return fud; |
| 1505 | } |
| 1506 | EXPORT_SYMBOL_GPL(fuse_dev_alloc); |
| 1507 | |
| 1508 | void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc) |
| 1509 | { |
| 1510 | fud->fc = fuse_conn_get(fc); |
| 1511 | spin_lock(&fc->lock); |
| 1512 | list_add_tail(&fud->entry, &fc->devices); |
| 1513 | spin_unlock(&fc->lock); |
| 1514 | } |
| 1515 | EXPORT_SYMBOL_GPL(fuse_dev_install); |
| 1516 | |
| 1517 | struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc) |
| 1518 | { |
| 1519 | struct fuse_dev *fud; |
| 1520 | |
| 1521 | fud = fuse_dev_alloc(); |
| 1522 | if (!fud) |
| 1523 | return NULL; |
| 1524 | |
| 1525 | fuse_dev_install(fud, fc); |
| 1526 | return fud; |
| 1527 | } |
| 1528 | EXPORT_SYMBOL_GPL(fuse_dev_alloc_install); |
| 1529 | |
| 1530 | void fuse_dev_free(struct fuse_dev *fud) |
| 1531 | { |
| 1532 | struct fuse_conn *fc = fud->fc; |
| 1533 | |
| 1534 | if (fc) { |
| 1535 | spin_lock(&fc->lock); |
| 1536 | list_del(&fud->entry); |
| 1537 | spin_unlock(&fc->lock); |
| 1538 | |
| 1539 | fuse_conn_put(fc); |
| 1540 | } |
| 1541 | kfree(fud->pq.processing); |
| 1542 | kfree(fud); |
| 1543 | } |
| 1544 | EXPORT_SYMBOL_GPL(fuse_dev_free); |
| 1545 | |
| 1546 | static void fuse_fill_attr_from_inode(struct fuse_attr *attr, |
| 1547 | const struct fuse_inode *fi) |
| 1548 | { |
| 1549 | struct timespec64 atime = inode_get_atime(&fi->inode); |
| 1550 | struct timespec64 mtime = inode_get_mtime(&fi->inode); |
| 1551 | struct timespec64 ctime = inode_get_ctime(&fi->inode); |
| 1552 | |
| 1553 | *attr = (struct fuse_attr){ |
| 1554 | .ino = fi->inode.i_ino, |
| 1555 | .size = fi->inode.i_size, |
| 1556 | .blocks = fi->inode.i_blocks, |
| 1557 | .atime = atime.tv_sec, |
| 1558 | .mtime = mtime.tv_sec, |
| 1559 | .ctime = ctime.tv_sec, |
| 1560 | .atimensec = atime.tv_nsec, |
| 1561 | .mtimensec = mtime.tv_nsec, |
| 1562 | .ctimensec = ctime.tv_nsec, |
| 1563 | .mode = fi->inode.i_mode, |
| 1564 | .nlink = fi->inode.i_nlink, |
| 1565 | .uid = __kuid_val(fi->inode.i_uid), |
| 1566 | .gid = __kgid_val(fi->inode.i_gid), |
| 1567 | .rdev = fi->inode.i_rdev, |
| 1568 | .blksize = 1u << fi->inode.i_blkbits, |
| 1569 | }; |
| 1570 | } |
| 1571 | |
| 1572 | static void fuse_sb_defaults(struct super_block *sb) |
| 1573 | { |
| 1574 | sb->s_magic = FUSE_SUPER_MAGIC; |
| 1575 | sb->s_op = &fuse_super_operations; |
| 1576 | sb->s_xattr = fuse_xattr_handlers; |
| 1577 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
| 1578 | sb->s_time_gran = 1; |
| 1579 | sb->s_export_op = &fuse_export_operations; |
| 1580 | sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE; |
| 1581 | sb->s_iflags |= SB_I_NOIDMAP; |
| 1582 | if (sb->s_user_ns != &init_user_ns) |
| 1583 | sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER; |
| 1584 | sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION); |
| 1585 | } |
| 1586 | |
| 1587 | static int fuse_fill_super_submount(struct super_block *sb, |
| 1588 | struct fuse_inode *parent_fi) |
| 1589 | { |
| 1590 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
| 1591 | struct super_block *parent_sb = parent_fi->inode.i_sb; |
| 1592 | struct fuse_attr root_attr; |
| 1593 | struct inode *root; |
| 1594 | struct fuse_submount_lookup *sl; |
| 1595 | struct fuse_inode *fi; |
| 1596 | |
| 1597 | fuse_sb_defaults(sb); |
| 1598 | fm->sb = sb; |
| 1599 | |
| 1600 | WARN_ON(sb->s_bdi != &noop_backing_dev_info); |
| 1601 | sb->s_bdi = bdi_get(parent_sb->s_bdi); |
| 1602 | |
| 1603 | sb->s_xattr = parent_sb->s_xattr; |
| 1604 | sb->s_export_op = parent_sb->s_export_op; |
| 1605 | sb->s_time_gran = parent_sb->s_time_gran; |
| 1606 | sb->s_blocksize = parent_sb->s_blocksize; |
| 1607 | sb->s_blocksize_bits = parent_sb->s_blocksize_bits; |
| 1608 | sb->s_subtype = kstrdup(parent_sb->s_subtype, GFP_KERNEL); |
| 1609 | if (parent_sb->s_subtype && !sb->s_subtype) |
| 1610 | return -ENOMEM; |
| 1611 | |
| 1612 | fuse_fill_attr_from_inode(&root_attr, parent_fi); |
| 1613 | root = fuse_iget(sb, parent_fi->nodeid, 0, &root_attr, 0, 0); |
| 1614 | /* |
| 1615 | * This inode is just a duplicate, so it is not looked up and |
| 1616 | * its nlookup should not be incremented. fuse_iget() does |
| 1617 | * that, though, so undo it here. |
| 1618 | */ |
| 1619 | fi = get_fuse_inode(root); |
| 1620 | fi->nlookup--; |
| 1621 | |
| 1622 | sb->s_d_op = &fuse_dentry_operations; |
| 1623 | sb->s_root = d_make_root(root); |
| 1624 | if (!sb->s_root) |
| 1625 | return -ENOMEM; |
| 1626 | |
| 1627 | /* |
| 1628 | * Grab the parent's submount_lookup pointer and take a |
| 1629 | * reference on the shared nlookup from the parent. This is to |
| 1630 | * prevent the last forget for this nodeid from getting |
| 1631 | * triggered until all users have finished with it. |
| 1632 | */ |
| 1633 | sl = parent_fi->submount_lookup; |
| 1634 | WARN_ON(!sl); |
| 1635 | if (sl) { |
| 1636 | refcount_inc(&sl->count); |
| 1637 | fi->submount_lookup = sl; |
| 1638 | } |
| 1639 | |
| 1640 | return 0; |
| 1641 | } |
| 1642 | |
| 1643 | /* Filesystem context private data holds the FUSE inode of the mount point */ |
| 1644 | static int fuse_get_tree_submount(struct fs_context *fsc) |
| 1645 | { |
| 1646 | struct fuse_mount *fm; |
| 1647 | struct fuse_inode *mp_fi = fsc->fs_private; |
| 1648 | struct fuse_conn *fc = get_fuse_conn(&mp_fi->inode); |
| 1649 | struct super_block *sb; |
| 1650 | int err; |
| 1651 | |
| 1652 | fm = kzalloc(sizeof(struct fuse_mount), GFP_KERNEL); |
| 1653 | if (!fm) |
| 1654 | return -ENOMEM; |
| 1655 | |
| 1656 | fm->fc = fuse_conn_get(fc); |
| 1657 | fsc->s_fs_info = fm; |
| 1658 | sb = sget_fc(fsc, NULL, set_anon_super_fc); |
| 1659 | if (fsc->s_fs_info) |
| 1660 | fuse_mount_destroy(fm); |
| 1661 | if (IS_ERR(sb)) |
| 1662 | return PTR_ERR(sb); |
| 1663 | |
| 1664 | /* Initialize superblock, making @mp_fi its root */ |
| 1665 | err = fuse_fill_super_submount(sb, mp_fi); |
| 1666 | if (err) { |
| 1667 | deactivate_locked_super(sb); |
| 1668 | return err; |
| 1669 | } |
| 1670 | |
| 1671 | down_write(&fc->killsb); |
| 1672 | list_add_tail(&fm->fc_entry, &fc->mounts); |
| 1673 | up_write(&fc->killsb); |
| 1674 | |
| 1675 | sb->s_flags |= SB_ACTIVE; |
| 1676 | fsc->root = dget(sb->s_root); |
| 1677 | |
| 1678 | return 0; |
| 1679 | } |
| 1680 | |
| 1681 | static const struct fs_context_operations fuse_context_submount_ops = { |
| 1682 | .get_tree = fuse_get_tree_submount, |
| 1683 | }; |
| 1684 | |
| 1685 | int fuse_init_fs_context_submount(struct fs_context *fsc) |
| 1686 | { |
| 1687 | fsc->ops = &fuse_context_submount_ops; |
| 1688 | return 0; |
| 1689 | } |
| 1690 | EXPORT_SYMBOL_GPL(fuse_init_fs_context_submount); |
| 1691 | |
| 1692 | int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx) |
| 1693 | { |
| 1694 | struct fuse_dev *fud = NULL; |
| 1695 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
| 1696 | struct fuse_conn *fc = fm->fc; |
| 1697 | struct inode *root; |
| 1698 | struct dentry *root_dentry; |
| 1699 | int err; |
| 1700 | |
| 1701 | err = -EINVAL; |
| 1702 | if (sb->s_flags & SB_MANDLOCK) |
| 1703 | goto err; |
| 1704 | |
| 1705 | rcu_assign_pointer(fc->curr_bucket, fuse_sync_bucket_alloc()); |
| 1706 | fuse_sb_defaults(sb); |
| 1707 | |
| 1708 | if (ctx->is_bdev) { |
| 1709 | #ifdef CONFIG_BLOCK |
| 1710 | err = -EINVAL; |
| 1711 | if (!sb_set_blocksize(sb, ctx->blksize)) |
| 1712 | goto err; |
| 1713 | #endif |
| 1714 | } else { |
| 1715 | sb->s_blocksize = PAGE_SIZE; |
| 1716 | sb->s_blocksize_bits = PAGE_SHIFT; |
| 1717 | } |
| 1718 | |
| 1719 | sb->s_subtype = ctx->subtype; |
| 1720 | ctx->subtype = NULL; |
| 1721 | if (IS_ENABLED(CONFIG_FUSE_DAX)) { |
| 1722 | err = fuse_dax_conn_alloc(fc, ctx->dax_mode, ctx->dax_dev); |
| 1723 | if (err) |
| 1724 | goto err; |
| 1725 | } |
| 1726 | |
| 1727 | if (ctx->fudptr) { |
| 1728 | err = -ENOMEM; |
| 1729 | fud = fuse_dev_alloc_install(fc); |
| 1730 | if (!fud) |
| 1731 | goto err_free_dax; |
| 1732 | } |
| 1733 | |
| 1734 | fc->dev = sb->s_dev; |
| 1735 | fm->sb = sb; |
| 1736 | err = fuse_bdi_init(fc, sb); |
| 1737 | if (err) |
| 1738 | goto err_dev_free; |
| 1739 | |
| 1740 | /* Handle umasking inside the fuse code */ |
| 1741 | if (sb->s_flags & SB_POSIXACL) |
| 1742 | fc->dont_mask = 1; |
| 1743 | sb->s_flags |= SB_POSIXACL; |
| 1744 | |
| 1745 | fc->default_permissions = ctx->default_permissions; |
| 1746 | fc->allow_other = ctx->allow_other; |
| 1747 | fc->user_id = ctx->user_id; |
| 1748 | fc->group_id = ctx->group_id; |
| 1749 | fc->legacy_opts_show = ctx->legacy_opts_show; |
| 1750 | fc->max_read = max_t(unsigned int, 4096, ctx->max_read); |
| 1751 | fc->destroy = ctx->destroy; |
| 1752 | fc->no_control = ctx->no_control; |
| 1753 | fc->no_force_umount = ctx->no_force_umount; |
| 1754 | |
| 1755 | err = -ENOMEM; |
| 1756 | root = fuse_get_root_inode(sb, ctx->rootmode); |
| 1757 | sb->s_d_op = &fuse_root_dentry_operations; |
| 1758 | root_dentry = d_make_root(root); |
| 1759 | if (!root_dentry) |
| 1760 | goto err_dev_free; |
| 1761 | /* Root dentry doesn't have .d_revalidate */ |
| 1762 | sb->s_d_op = &fuse_dentry_operations; |
| 1763 | |
| 1764 | mutex_lock(&fuse_mutex); |
| 1765 | err = -EINVAL; |
| 1766 | if (ctx->fudptr && *ctx->fudptr) |
| 1767 | goto err_unlock; |
| 1768 | |
| 1769 | err = fuse_ctl_add_conn(fc); |
| 1770 | if (err) |
| 1771 | goto err_unlock; |
| 1772 | |
| 1773 | list_add_tail(&fc->entry, &fuse_conn_list); |
| 1774 | sb->s_root = root_dentry; |
| 1775 | if (ctx->fudptr) |
| 1776 | *ctx->fudptr = fud; |
| 1777 | mutex_unlock(&fuse_mutex); |
| 1778 | return 0; |
| 1779 | |
| 1780 | err_unlock: |
| 1781 | mutex_unlock(&fuse_mutex); |
| 1782 | dput(root_dentry); |
| 1783 | err_dev_free: |
| 1784 | if (fud) |
| 1785 | fuse_dev_free(fud); |
| 1786 | err_free_dax: |
| 1787 | if (IS_ENABLED(CONFIG_FUSE_DAX)) |
| 1788 | fuse_dax_conn_free(fc); |
| 1789 | err: |
| 1790 | return err; |
| 1791 | } |
| 1792 | EXPORT_SYMBOL_GPL(fuse_fill_super_common); |
| 1793 | |
| 1794 | static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) |
| 1795 | { |
| 1796 | struct fuse_fs_context *ctx = fsc->fs_private; |
| 1797 | int err; |
| 1798 | |
| 1799 | if (!ctx->file || !ctx->rootmode_present || |
| 1800 | !ctx->user_id_present || !ctx->group_id_present) |
| 1801 | return -EINVAL; |
| 1802 | |
| 1803 | /* |
| 1804 | * Require mount to happen from the same user namespace which |
| 1805 | * opened /dev/fuse to prevent potential attacks. |
| 1806 | */ |
| 1807 | if ((ctx->file->f_op != &fuse_dev_operations) || |
| 1808 | (ctx->file->f_cred->user_ns != sb->s_user_ns)) |
| 1809 | return -EINVAL; |
| 1810 | ctx->fudptr = &ctx->file->private_data; |
| 1811 | |
| 1812 | err = fuse_fill_super_common(sb, ctx); |
| 1813 | if (err) |
| 1814 | return err; |
| 1815 | /* file->private_data shall be visible on all CPUs after this */ |
| 1816 | smp_mb(); |
| 1817 | fuse_send_init(get_fuse_mount_super(sb)); |
| 1818 | return 0; |
| 1819 | } |
| 1820 | |
| 1821 | /* |
| 1822 | * This is the path where user supplied an already initialized fuse dev. In |
| 1823 | * this case never create a new super if the old one is gone. |
| 1824 | */ |
| 1825 | static int fuse_set_no_super(struct super_block *sb, struct fs_context *fsc) |
| 1826 | { |
| 1827 | return -ENOTCONN; |
| 1828 | } |
| 1829 | |
| 1830 | static int fuse_test_super(struct super_block *sb, struct fs_context *fsc) |
| 1831 | { |
| 1832 | |
| 1833 | return fsc->sget_key == get_fuse_conn_super(sb); |
| 1834 | } |
| 1835 | |
| 1836 | static int fuse_get_tree(struct fs_context *fsc) |
| 1837 | { |
| 1838 | struct fuse_fs_context *ctx = fsc->fs_private; |
| 1839 | struct fuse_dev *fud; |
| 1840 | struct fuse_conn *fc; |
| 1841 | struct fuse_mount *fm; |
| 1842 | struct super_block *sb; |
| 1843 | int err; |
| 1844 | |
| 1845 | fc = kmalloc(sizeof(*fc), GFP_KERNEL); |
| 1846 | if (!fc) |
| 1847 | return -ENOMEM; |
| 1848 | |
| 1849 | fm = kzalloc(sizeof(*fm), GFP_KERNEL); |
| 1850 | if (!fm) { |
| 1851 | kfree(fc); |
| 1852 | return -ENOMEM; |
| 1853 | } |
| 1854 | |
| 1855 | fuse_conn_init(fc, fm, fsc->user_ns, &fuse_dev_fiq_ops, NULL); |
| 1856 | fc->release = fuse_free_conn; |
| 1857 | |
| 1858 | fsc->s_fs_info = fm; |
| 1859 | |
| 1860 | if (ctx->fd_present) |
| 1861 | ctx->file = fget(ctx->fd); |
| 1862 | |
| 1863 | if (IS_ENABLED(CONFIG_BLOCK) && ctx->is_bdev) { |
| 1864 | err = get_tree_bdev(fsc, fuse_fill_super); |
| 1865 | goto out; |
| 1866 | } |
| 1867 | /* |
| 1868 | * While block dev mount can be initialized with a dummy device fd |
| 1869 | * (found by device name), normal fuse mounts can't |
| 1870 | */ |
| 1871 | err = -EINVAL; |
| 1872 | if (!ctx->file) |
| 1873 | goto out; |
| 1874 | |
| 1875 | /* |
| 1876 | * Allow creating a fuse mount with an already initialized fuse |
| 1877 | * connection |
| 1878 | */ |
| 1879 | fud = READ_ONCE(ctx->file->private_data); |
| 1880 | if (ctx->file->f_op == &fuse_dev_operations && fud) { |
| 1881 | fsc->sget_key = fud->fc; |
| 1882 | sb = sget_fc(fsc, fuse_test_super, fuse_set_no_super); |
| 1883 | err = PTR_ERR_OR_ZERO(sb); |
| 1884 | if (!IS_ERR(sb)) |
| 1885 | fsc->root = dget(sb->s_root); |
| 1886 | } else { |
| 1887 | err = get_tree_nodev(fsc, fuse_fill_super); |
| 1888 | } |
| 1889 | out: |
| 1890 | if (fsc->s_fs_info) |
| 1891 | fuse_mount_destroy(fm); |
| 1892 | if (ctx->file) |
| 1893 | fput(ctx->file); |
| 1894 | return err; |
| 1895 | } |
| 1896 | |
| 1897 | static const struct fs_context_operations fuse_context_ops = { |
| 1898 | .free = fuse_free_fsc, |
| 1899 | .parse_param = fuse_parse_param, |
| 1900 | .reconfigure = fuse_reconfigure, |
| 1901 | .get_tree = fuse_get_tree, |
| 1902 | }; |
| 1903 | |
| 1904 | /* |
| 1905 | * Set up the filesystem mount context. |
| 1906 | */ |
| 1907 | static int fuse_init_fs_context(struct fs_context *fsc) |
| 1908 | { |
| 1909 | struct fuse_fs_context *ctx; |
| 1910 | |
| 1911 | ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL); |
| 1912 | if (!ctx) |
| 1913 | return -ENOMEM; |
| 1914 | |
| 1915 | ctx->max_read = ~0; |
| 1916 | ctx->blksize = FUSE_DEFAULT_BLKSIZE; |
| 1917 | ctx->legacy_opts_show = true; |
| 1918 | |
| 1919 | #ifdef CONFIG_BLOCK |
| 1920 | if (fsc->fs_type == &fuseblk_fs_type) { |
| 1921 | ctx->is_bdev = true; |
| 1922 | ctx->destroy = true; |
| 1923 | } |
| 1924 | #endif |
| 1925 | |
| 1926 | fsc->fs_private = ctx; |
| 1927 | fsc->ops = &fuse_context_ops; |
| 1928 | return 0; |
| 1929 | } |
| 1930 | |
| 1931 | bool fuse_mount_remove(struct fuse_mount *fm) |
| 1932 | { |
| 1933 | struct fuse_conn *fc = fm->fc; |
| 1934 | bool last = false; |
| 1935 | |
| 1936 | down_write(&fc->killsb); |
| 1937 | list_del_init(&fm->fc_entry); |
| 1938 | if (list_empty(&fc->mounts)) |
| 1939 | last = true; |
| 1940 | up_write(&fc->killsb); |
| 1941 | |
| 1942 | return last; |
| 1943 | } |
| 1944 | EXPORT_SYMBOL_GPL(fuse_mount_remove); |
| 1945 | |
| 1946 | void fuse_conn_destroy(struct fuse_mount *fm) |
| 1947 | { |
| 1948 | struct fuse_conn *fc = fm->fc; |
| 1949 | |
| 1950 | if (fc->destroy) |
| 1951 | fuse_send_destroy(fm); |
| 1952 | |
| 1953 | fuse_abort_conn(fc); |
| 1954 | fuse_wait_aborted(fc); |
| 1955 | |
| 1956 | if (!list_empty(&fc->entry)) { |
| 1957 | mutex_lock(&fuse_mutex); |
| 1958 | list_del(&fc->entry); |
| 1959 | fuse_ctl_remove_conn(fc); |
| 1960 | mutex_unlock(&fuse_mutex); |
| 1961 | } |
| 1962 | } |
| 1963 | EXPORT_SYMBOL_GPL(fuse_conn_destroy); |
| 1964 | |
| 1965 | static void fuse_sb_destroy(struct super_block *sb) |
| 1966 | { |
| 1967 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
| 1968 | bool last; |
| 1969 | |
| 1970 | if (sb->s_root) { |
| 1971 | last = fuse_mount_remove(fm); |
| 1972 | if (last) |
| 1973 | fuse_conn_destroy(fm); |
| 1974 | } |
| 1975 | } |
| 1976 | |
| 1977 | void fuse_mount_destroy(struct fuse_mount *fm) |
| 1978 | { |
| 1979 | fuse_conn_put(fm->fc); |
| 1980 | kfree_rcu(fm, rcu); |
| 1981 | } |
| 1982 | EXPORT_SYMBOL(fuse_mount_destroy); |
| 1983 | |
| 1984 | static void fuse_kill_sb_anon(struct super_block *sb) |
| 1985 | { |
| 1986 | fuse_sb_destroy(sb); |
| 1987 | kill_anon_super(sb); |
| 1988 | fuse_mount_destroy(get_fuse_mount_super(sb)); |
| 1989 | } |
| 1990 | |
| 1991 | static struct file_system_type fuse_fs_type = { |
| 1992 | .owner = THIS_MODULE, |
| 1993 | .name = "fuse", |
| 1994 | .fs_flags = FS_HAS_SUBTYPE | FS_USERNS_MOUNT | FS_ALLOW_IDMAP, |
| 1995 | .init_fs_context = fuse_init_fs_context, |
| 1996 | .parameters = fuse_fs_parameters, |
| 1997 | .kill_sb = fuse_kill_sb_anon, |
| 1998 | }; |
| 1999 | MODULE_ALIAS_FS("fuse"); |
| 2000 | |
| 2001 | #ifdef CONFIG_BLOCK |
| 2002 | static void fuse_kill_sb_blk(struct super_block *sb) |
| 2003 | { |
| 2004 | fuse_sb_destroy(sb); |
| 2005 | kill_block_super(sb); |
| 2006 | fuse_mount_destroy(get_fuse_mount_super(sb)); |
| 2007 | } |
| 2008 | |
| 2009 | static struct file_system_type fuseblk_fs_type = { |
| 2010 | .owner = THIS_MODULE, |
| 2011 | .name = "fuseblk", |
| 2012 | .init_fs_context = fuse_init_fs_context, |
| 2013 | .parameters = fuse_fs_parameters, |
| 2014 | .kill_sb = fuse_kill_sb_blk, |
| 2015 | .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE | FS_ALLOW_IDMAP, |
| 2016 | }; |
| 2017 | MODULE_ALIAS_FS("fuseblk"); |
| 2018 | |
| 2019 | static inline int register_fuseblk(void) |
| 2020 | { |
| 2021 | return register_filesystem(&fuseblk_fs_type); |
| 2022 | } |
| 2023 | |
| 2024 | static inline void unregister_fuseblk(void) |
| 2025 | { |
| 2026 | unregister_filesystem(&fuseblk_fs_type); |
| 2027 | } |
| 2028 | #else |
| 2029 | static inline int register_fuseblk(void) |
| 2030 | { |
| 2031 | return 0; |
| 2032 | } |
| 2033 | |
| 2034 | static inline void unregister_fuseblk(void) |
| 2035 | { |
| 2036 | } |
| 2037 | #endif |
| 2038 | |
| 2039 | static void fuse_inode_init_once(void *foo) |
| 2040 | { |
| 2041 | struct inode *inode = foo; |
| 2042 | |
| 2043 | inode_init_once(inode); |
| 2044 | } |
| 2045 | |
| 2046 | static int __init fuse_fs_init(void) |
| 2047 | { |
| 2048 | int err; |
| 2049 | |
| 2050 | fuse_inode_cachep = kmem_cache_create("fuse_inode", |
| 2051 | sizeof(struct fuse_inode), 0, |
| 2052 | SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT, |
| 2053 | fuse_inode_init_once); |
| 2054 | err = -ENOMEM; |
| 2055 | if (!fuse_inode_cachep) |
| 2056 | goto out; |
| 2057 | |
| 2058 | err = register_fuseblk(); |
| 2059 | if (err) |
| 2060 | goto out2; |
| 2061 | |
| 2062 | err = register_filesystem(&fuse_fs_type); |
| 2063 | if (err) |
| 2064 | goto out3; |
| 2065 | |
| 2066 | return 0; |
| 2067 | |
| 2068 | out3: |
| 2069 | unregister_fuseblk(); |
| 2070 | out2: |
| 2071 | kmem_cache_destroy(fuse_inode_cachep); |
| 2072 | out: |
| 2073 | return err; |
| 2074 | } |
| 2075 | |
| 2076 | static void fuse_fs_cleanup(void) |
| 2077 | { |
| 2078 | unregister_filesystem(&fuse_fs_type); |
| 2079 | unregister_fuseblk(); |
| 2080 | |
| 2081 | /* |
| 2082 | * Make sure all delayed rcu free inodes are flushed before we |
| 2083 | * destroy cache. |
| 2084 | */ |
| 2085 | rcu_barrier(); |
| 2086 | kmem_cache_destroy(fuse_inode_cachep); |
| 2087 | } |
| 2088 | |
| 2089 | static struct kobject *fuse_kobj; |
| 2090 | |
| 2091 | static int fuse_sysfs_init(void) |
| 2092 | { |
| 2093 | int err; |
| 2094 | |
| 2095 | fuse_kobj = kobject_create_and_add("fuse", fs_kobj); |
| 2096 | if (!fuse_kobj) { |
| 2097 | err = -ENOMEM; |
| 2098 | goto out_err; |
| 2099 | } |
| 2100 | |
| 2101 | err = sysfs_create_mount_point(fuse_kobj, "connections"); |
| 2102 | if (err) |
| 2103 | goto out_fuse_unregister; |
| 2104 | |
| 2105 | return 0; |
| 2106 | |
| 2107 | out_fuse_unregister: |
| 2108 | kobject_put(fuse_kobj); |
| 2109 | out_err: |
| 2110 | return err; |
| 2111 | } |
| 2112 | |
| 2113 | static void fuse_sysfs_cleanup(void) |
| 2114 | { |
| 2115 | sysfs_remove_mount_point(fuse_kobj, "connections"); |
| 2116 | kobject_put(fuse_kobj); |
| 2117 | } |
| 2118 | |
| 2119 | static int __init fuse_init(void) |
| 2120 | { |
| 2121 | int res; |
| 2122 | |
| 2123 | pr_info("init (API version %i.%i)\n", |
| 2124 | FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION); |
| 2125 | |
| 2126 | INIT_LIST_HEAD(&fuse_conn_list); |
| 2127 | res = fuse_fs_init(); |
| 2128 | if (res) |
| 2129 | goto err; |
| 2130 | |
| 2131 | res = fuse_dev_init(); |
| 2132 | if (res) |
| 2133 | goto err_fs_cleanup; |
| 2134 | |
| 2135 | res = fuse_sysfs_init(); |
| 2136 | if (res) |
| 2137 | goto err_dev_cleanup; |
| 2138 | |
| 2139 | res = fuse_ctl_init(); |
| 2140 | if (res) |
| 2141 | goto err_sysfs_cleanup; |
| 2142 | |
| 2143 | sanitize_global_limit(&max_user_bgreq); |
| 2144 | sanitize_global_limit(&max_user_congthresh); |
| 2145 | |
| 2146 | return 0; |
| 2147 | |
| 2148 | err_sysfs_cleanup: |
| 2149 | fuse_sysfs_cleanup(); |
| 2150 | err_dev_cleanup: |
| 2151 | fuse_dev_cleanup(); |
| 2152 | err_fs_cleanup: |
| 2153 | fuse_fs_cleanup(); |
| 2154 | err: |
| 2155 | return res; |
| 2156 | } |
| 2157 | |
| 2158 | static void __exit fuse_exit(void) |
| 2159 | { |
| 2160 | pr_debug("exit\n"); |
| 2161 | |
| 2162 | fuse_ctl_cleanup(); |
| 2163 | fuse_sysfs_cleanup(); |
| 2164 | fuse_fs_cleanup(); |
| 2165 | fuse_dev_cleanup(); |
| 2166 | } |
| 2167 | |
| 2168 | module_init(fuse_init); |
| 2169 | module_exit(fuse_exit); |