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/parser.h> 19 #include <linux/statfs.h> 20 #include <linux/random.h> 21 #include <linux/sched.h> 22 #include <linux/exportfs.h> 23 #include <linux/posix_acl.h> 24 #include <linux/pid_namespace.h> 25 26 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); 27 MODULE_DESCRIPTION("Filesystem in Userspace"); 28 MODULE_LICENSE("GPL"); 29 30 static struct kmem_cache *fuse_inode_cachep; 31 struct list_head fuse_conn_list; 32 DEFINE_MUTEX(fuse_mutex); 33 34 static int set_global_limit(const char *val, const struct kernel_param *kp); 35 36 unsigned max_user_bgreq; 37 module_param_call(max_user_bgreq, set_global_limit, param_get_uint, 38 &max_user_bgreq, 0644); 39 __MODULE_PARM_TYPE(max_user_bgreq, "uint"); 40 MODULE_PARM_DESC(max_user_bgreq, 41 "Global limit for the maximum number of backgrounded requests an " 42 "unprivileged user can set"); 43 44 unsigned max_user_congthresh; 45 module_param_call(max_user_congthresh, set_global_limit, param_get_uint, 46 &max_user_congthresh, 0644); 47 __MODULE_PARM_TYPE(max_user_congthresh, "uint"); 48 MODULE_PARM_DESC(max_user_congthresh, 49 "Global limit for the maximum congestion threshold an " 50 "unprivileged user can set"); 51 52 #define FUSE_SUPER_MAGIC 0x65735546 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 struct fuse_mount_data { 63 int fd; 64 unsigned rootmode; 65 kuid_t user_id; 66 kgid_t group_id; 67 unsigned fd_present:1; 68 unsigned rootmode_present:1; 69 unsigned user_id_present:1; 70 unsigned group_id_present:1; 71 unsigned default_permissions:1; 72 unsigned allow_other:1; 73 unsigned max_read; 74 unsigned blksize; 75 }; 76 77 struct fuse_forget_link *fuse_alloc_forget(void) 78 { 79 return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL); 80 } 81 82 static struct inode *fuse_alloc_inode(struct super_block *sb) 83 { 84 struct inode *inode; 85 struct fuse_inode *fi; 86 87 inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL); 88 if (!inode) 89 return NULL; 90 91 fi = get_fuse_inode(inode); 92 fi->i_time = 0; 93 fi->inval_mask = 0; 94 fi->nodeid = 0; 95 fi->nlookup = 0; 96 fi->attr_version = 0; 97 fi->orig_ino = 0; 98 fi->state = 0; 99 mutex_init(&fi->mutex); 100 fi->forget = fuse_alloc_forget(); 101 if (!fi->forget) { 102 kmem_cache_free(fuse_inode_cachep, inode); 103 return NULL; 104 } 105 106 return inode; 107 } 108 109 static void fuse_i_callback(struct rcu_head *head) 110 { 111 struct inode *inode = container_of(head, struct inode, i_rcu); 112 kmem_cache_free(fuse_inode_cachep, inode); 113 } 114 115 static void fuse_destroy_inode(struct inode *inode) 116 { 117 struct fuse_inode *fi = get_fuse_inode(inode); 118 if (S_ISREG(inode->i_mode) && !is_bad_inode(inode)) { 119 WARN_ON(!list_empty(&fi->write_files)); 120 WARN_ON(!list_empty(&fi->queued_writes)); 121 } 122 mutex_destroy(&fi->mutex); 123 kfree(fi->forget); 124 call_rcu(&inode->i_rcu, fuse_i_callback); 125 } 126 127 static void fuse_evict_inode(struct inode *inode) 128 { 129 truncate_inode_pages_final(&inode->i_data); 130 clear_inode(inode); 131 if (inode->i_sb->s_flags & SB_ACTIVE) { 132 struct fuse_conn *fc = get_fuse_conn(inode); 133 struct fuse_inode *fi = get_fuse_inode(inode); 134 fuse_queue_forget(fc, fi->forget, fi->nodeid, fi->nlookup); 135 fi->forget = NULL; 136 } 137 } 138 139 static int fuse_remount_fs(struct super_block *sb, int *flags, char *data) 140 { 141 sync_filesystem(sb); 142 if (*flags & SB_MANDLOCK) 143 return -EINVAL; 144 145 return 0; 146 } 147 148 /* 149 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down 150 * so that it will fit. 151 */ 152 static ino_t fuse_squash_ino(u64 ino64) 153 { 154 ino_t ino = (ino_t) ino64; 155 if (sizeof(ino_t) < sizeof(u64)) 156 ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8; 157 return ino; 158 } 159 160 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr, 161 u64 attr_valid) 162 { 163 struct fuse_conn *fc = get_fuse_conn(inode); 164 struct fuse_inode *fi = get_fuse_inode(inode); 165 166 fi->attr_version = ++fc->attr_version; 167 fi->i_time = attr_valid; 168 WRITE_ONCE(fi->inval_mask, 0); 169 170 inode->i_ino = fuse_squash_ino(attr->ino); 171 inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777); 172 set_nlink(inode, attr->nlink); 173 inode->i_uid = make_kuid(fc->user_ns, attr->uid); 174 inode->i_gid = make_kgid(fc->user_ns, attr->gid); 175 inode->i_blocks = attr->blocks; 176 inode->i_atime.tv_sec = attr->atime; 177 inode->i_atime.tv_nsec = attr->atimensec; 178 /* mtime from server may be stale due to local buffered write */ 179 if (!fc->writeback_cache || !S_ISREG(inode->i_mode)) { 180 inode->i_mtime.tv_sec = attr->mtime; 181 inode->i_mtime.tv_nsec = attr->mtimensec; 182 inode->i_ctime.tv_sec = attr->ctime; 183 inode->i_ctime.tv_nsec = attr->ctimensec; 184 } 185 186 if (attr->blksize != 0) 187 inode->i_blkbits = ilog2(attr->blksize); 188 else 189 inode->i_blkbits = inode->i_sb->s_blocksize_bits; 190 191 /* 192 * Don't set the sticky bit in i_mode, unless we want the VFS 193 * to check permissions. This prevents failures due to the 194 * check in may_delete(). 195 */ 196 fi->orig_i_mode = inode->i_mode; 197 if (!fc->default_permissions) 198 inode->i_mode &= ~S_ISVTX; 199 200 fi->orig_ino = attr->ino; 201 } 202 203 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr, 204 u64 attr_valid, u64 attr_version) 205 { 206 struct fuse_conn *fc = get_fuse_conn(inode); 207 struct fuse_inode *fi = get_fuse_inode(inode); 208 bool is_wb = fc->writeback_cache; 209 loff_t oldsize; 210 struct timespec64 old_mtime; 211 212 spin_lock(&fc->lock); 213 if ((attr_version != 0 && fi->attr_version > attr_version) || 214 test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) { 215 spin_unlock(&fc->lock); 216 return; 217 } 218 219 old_mtime = inode->i_mtime; 220 fuse_change_attributes_common(inode, attr, attr_valid); 221 222 oldsize = inode->i_size; 223 /* 224 * In case of writeback_cache enabled, the cached writes beyond EOF 225 * extend local i_size without keeping userspace server in sync. So, 226 * attr->size coming from server can be stale. We cannot trust it. 227 */ 228 if (!is_wb || !S_ISREG(inode->i_mode)) 229 i_size_write(inode, attr->size); 230 spin_unlock(&fc->lock); 231 232 if (!is_wb && S_ISREG(inode->i_mode)) { 233 bool inval = false; 234 235 if (oldsize != attr->size) { 236 truncate_pagecache(inode, attr->size); 237 inval = true; 238 } else if (fc->auto_inval_data) { 239 struct timespec64 new_mtime = { 240 .tv_sec = attr->mtime, 241 .tv_nsec = attr->mtimensec, 242 }; 243 244 /* 245 * Auto inval mode also checks and invalidates if mtime 246 * has changed. 247 */ 248 if (!timespec64_equal(&old_mtime, &new_mtime)) 249 inval = true; 250 } 251 252 if (inval) 253 invalidate_inode_pages2(inode->i_mapping); 254 } 255 } 256 257 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr) 258 { 259 inode->i_mode = attr->mode & S_IFMT; 260 inode->i_size = attr->size; 261 inode->i_mtime.tv_sec = attr->mtime; 262 inode->i_mtime.tv_nsec = attr->mtimensec; 263 inode->i_ctime.tv_sec = attr->ctime; 264 inode->i_ctime.tv_nsec = attr->ctimensec; 265 if (S_ISREG(inode->i_mode)) { 266 fuse_init_common(inode); 267 fuse_init_file_inode(inode); 268 } else if (S_ISDIR(inode->i_mode)) 269 fuse_init_dir(inode); 270 else if (S_ISLNK(inode->i_mode)) 271 fuse_init_symlink(inode); 272 else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || 273 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { 274 fuse_init_common(inode); 275 init_special_inode(inode, inode->i_mode, 276 new_decode_dev(attr->rdev)); 277 } else 278 BUG(); 279 } 280 281 int fuse_inode_eq(struct inode *inode, void *_nodeidp) 282 { 283 u64 nodeid = *(u64 *) _nodeidp; 284 if (get_node_id(inode) == nodeid) 285 return 1; 286 else 287 return 0; 288 } 289 290 static int fuse_inode_set(struct inode *inode, void *_nodeidp) 291 { 292 u64 nodeid = *(u64 *) _nodeidp; 293 get_fuse_inode(inode)->nodeid = nodeid; 294 return 0; 295 } 296 297 struct inode *fuse_iget(struct super_block *sb, u64 nodeid, 298 int generation, struct fuse_attr *attr, 299 u64 attr_valid, u64 attr_version) 300 { 301 struct inode *inode; 302 struct fuse_inode *fi; 303 struct fuse_conn *fc = get_fuse_conn_super(sb); 304 305 retry: 306 inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid); 307 if (!inode) 308 return NULL; 309 310 if ((inode->i_state & I_NEW)) { 311 inode->i_flags |= S_NOATIME; 312 if (!fc->writeback_cache || !S_ISREG(attr->mode)) 313 inode->i_flags |= S_NOCMTIME; 314 inode->i_generation = generation; 315 fuse_init_inode(inode, attr); 316 unlock_new_inode(inode); 317 } else if ((inode->i_mode ^ attr->mode) & S_IFMT) { 318 /* Inode has changed type, any I/O on the old should fail */ 319 make_bad_inode(inode); 320 iput(inode); 321 goto retry; 322 } 323 324 fi = get_fuse_inode(inode); 325 spin_lock(&fc->lock); 326 fi->nlookup++; 327 spin_unlock(&fc->lock); 328 fuse_change_attributes(inode, attr, attr_valid, attr_version); 329 330 return inode; 331 } 332 333 int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid, 334 loff_t offset, loff_t len) 335 { 336 struct inode *inode; 337 pgoff_t pg_start; 338 pgoff_t pg_end; 339 340 inode = ilookup5(sb, nodeid, fuse_inode_eq, &nodeid); 341 if (!inode) 342 return -ENOENT; 343 344 fuse_invalidate_attr(inode); 345 forget_all_cached_acls(inode); 346 if (offset >= 0) { 347 pg_start = offset >> PAGE_SHIFT; 348 if (len <= 0) 349 pg_end = -1; 350 else 351 pg_end = (offset + len - 1) >> PAGE_SHIFT; 352 invalidate_inode_pages2_range(inode->i_mapping, 353 pg_start, pg_end); 354 } 355 iput(inode); 356 return 0; 357 } 358 359 bool fuse_lock_inode(struct inode *inode) 360 { 361 bool locked = false; 362 363 if (!get_fuse_conn(inode)->parallel_dirops) { 364 mutex_lock(&get_fuse_inode(inode)->mutex); 365 locked = true; 366 } 367 368 return locked; 369 } 370 371 void fuse_unlock_inode(struct inode *inode, bool locked) 372 { 373 if (locked) 374 mutex_unlock(&get_fuse_inode(inode)->mutex); 375 } 376 377 static void fuse_umount_begin(struct super_block *sb) 378 { 379 fuse_abort_conn(get_fuse_conn_super(sb), false); 380 } 381 382 static void fuse_send_destroy(struct fuse_conn *fc) 383 { 384 struct fuse_req *req = fc->destroy_req; 385 if (req && fc->conn_init) { 386 fc->destroy_req = NULL; 387 req->in.h.opcode = FUSE_DESTROY; 388 __set_bit(FR_FORCE, &req->flags); 389 __clear_bit(FR_BACKGROUND, &req->flags); 390 fuse_request_send(fc, req); 391 fuse_put_request(fc, req); 392 } 393 } 394 395 static void fuse_put_super(struct super_block *sb) 396 { 397 struct fuse_conn *fc = get_fuse_conn_super(sb); 398 399 mutex_lock(&fuse_mutex); 400 list_del(&fc->entry); 401 fuse_ctl_remove_conn(fc); 402 mutex_unlock(&fuse_mutex); 403 404 fuse_conn_put(fc); 405 } 406 407 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr) 408 { 409 stbuf->f_type = FUSE_SUPER_MAGIC; 410 stbuf->f_bsize = attr->bsize; 411 stbuf->f_frsize = attr->frsize; 412 stbuf->f_blocks = attr->blocks; 413 stbuf->f_bfree = attr->bfree; 414 stbuf->f_bavail = attr->bavail; 415 stbuf->f_files = attr->files; 416 stbuf->f_ffree = attr->ffree; 417 stbuf->f_namelen = attr->namelen; 418 /* fsid is left zero */ 419 } 420 421 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf) 422 { 423 struct super_block *sb = dentry->d_sb; 424 struct fuse_conn *fc = get_fuse_conn_super(sb); 425 FUSE_ARGS(args); 426 struct fuse_statfs_out outarg; 427 int err; 428 429 if (!fuse_allow_current_process(fc)) { 430 buf->f_type = FUSE_SUPER_MAGIC; 431 return 0; 432 } 433 434 memset(&outarg, 0, sizeof(outarg)); 435 args.in.numargs = 0; 436 args.in.h.opcode = FUSE_STATFS; 437 args.in.h.nodeid = get_node_id(d_inode(dentry)); 438 args.out.numargs = 1; 439 args.out.args[0].size = sizeof(outarg); 440 args.out.args[0].value = &outarg; 441 err = fuse_simple_request(fc, &args); 442 if (!err) 443 convert_fuse_statfs(buf, &outarg.st); 444 return err; 445 } 446 447 enum { 448 OPT_FD, 449 OPT_ROOTMODE, 450 OPT_USER_ID, 451 OPT_GROUP_ID, 452 OPT_DEFAULT_PERMISSIONS, 453 OPT_ALLOW_OTHER, 454 OPT_MAX_READ, 455 OPT_BLKSIZE, 456 OPT_ERR 457 }; 458 459 static const match_table_t tokens = { 460 {OPT_FD, "fd=%u"}, 461 {OPT_ROOTMODE, "rootmode=%o"}, 462 {OPT_USER_ID, "user_id=%u"}, 463 {OPT_GROUP_ID, "group_id=%u"}, 464 {OPT_DEFAULT_PERMISSIONS, "default_permissions"}, 465 {OPT_ALLOW_OTHER, "allow_other"}, 466 {OPT_MAX_READ, "max_read=%u"}, 467 {OPT_BLKSIZE, "blksize=%u"}, 468 {OPT_ERR, NULL} 469 }; 470 471 static int fuse_match_uint(substring_t *s, unsigned int *res) 472 { 473 int err = -ENOMEM; 474 char *buf = match_strdup(s); 475 if (buf) { 476 err = kstrtouint(buf, 10, res); 477 kfree(buf); 478 } 479 return err; 480 } 481 482 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev, 483 struct user_namespace *user_ns) 484 { 485 char *p; 486 memset(d, 0, sizeof(struct fuse_mount_data)); 487 d->max_read = ~0; 488 d->blksize = FUSE_DEFAULT_BLKSIZE; 489 490 while ((p = strsep(&opt, ",")) != NULL) { 491 int token; 492 int value; 493 unsigned uv; 494 substring_t args[MAX_OPT_ARGS]; 495 if (!*p) 496 continue; 497 498 token = match_token(p, tokens, args); 499 switch (token) { 500 case OPT_FD: 501 if (match_int(&args[0], &value)) 502 return 0; 503 d->fd = value; 504 d->fd_present = 1; 505 break; 506 507 case OPT_ROOTMODE: 508 if (match_octal(&args[0], &value)) 509 return 0; 510 if (!fuse_valid_type(value)) 511 return 0; 512 d->rootmode = value; 513 d->rootmode_present = 1; 514 break; 515 516 case OPT_USER_ID: 517 if (fuse_match_uint(&args[0], &uv)) 518 return 0; 519 d->user_id = make_kuid(user_ns, uv); 520 if (!uid_valid(d->user_id)) 521 return 0; 522 d->user_id_present = 1; 523 break; 524 525 case OPT_GROUP_ID: 526 if (fuse_match_uint(&args[0], &uv)) 527 return 0; 528 d->group_id = make_kgid(user_ns, uv); 529 if (!gid_valid(d->group_id)) 530 return 0; 531 d->group_id_present = 1; 532 break; 533 534 case OPT_DEFAULT_PERMISSIONS: 535 d->default_permissions = 1; 536 break; 537 538 case OPT_ALLOW_OTHER: 539 d->allow_other = 1; 540 break; 541 542 case OPT_MAX_READ: 543 if (match_int(&args[0], &value)) 544 return 0; 545 d->max_read = value; 546 break; 547 548 case OPT_BLKSIZE: 549 if (!is_bdev || match_int(&args[0], &value)) 550 return 0; 551 d->blksize = value; 552 break; 553 554 default: 555 return 0; 556 } 557 } 558 559 if (!d->fd_present || !d->rootmode_present || 560 !d->user_id_present || !d->group_id_present) 561 return 0; 562 563 return 1; 564 } 565 566 static int fuse_show_options(struct seq_file *m, struct dentry *root) 567 { 568 struct super_block *sb = root->d_sb; 569 struct fuse_conn *fc = get_fuse_conn_super(sb); 570 571 seq_printf(m, ",user_id=%u", from_kuid_munged(fc->user_ns, fc->user_id)); 572 seq_printf(m, ",group_id=%u", from_kgid_munged(fc->user_ns, fc->group_id)); 573 if (fc->default_permissions) 574 seq_puts(m, ",default_permissions"); 575 if (fc->allow_other) 576 seq_puts(m, ",allow_other"); 577 if (fc->max_read != ~0) 578 seq_printf(m, ",max_read=%u", fc->max_read); 579 if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE) 580 seq_printf(m, ",blksize=%lu", sb->s_blocksize); 581 return 0; 582 } 583 584 static void fuse_iqueue_init(struct fuse_iqueue *fiq) 585 { 586 memset(fiq, 0, sizeof(struct fuse_iqueue)); 587 init_waitqueue_head(&fiq->waitq); 588 INIT_LIST_HEAD(&fiq->pending); 589 INIT_LIST_HEAD(&fiq->interrupts); 590 fiq->forget_list_tail = &fiq->forget_list_head; 591 fiq->connected = 1; 592 } 593 594 static void fuse_pqueue_init(struct fuse_pqueue *fpq) 595 { 596 unsigned int i; 597 598 spin_lock_init(&fpq->lock); 599 for (i = 0; i < FUSE_PQ_HASH_SIZE; i++) 600 INIT_LIST_HEAD(&fpq->processing[i]); 601 INIT_LIST_HEAD(&fpq->io); 602 fpq->connected = 1; 603 } 604 605 void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns) 606 { 607 memset(fc, 0, sizeof(*fc)); 608 spin_lock_init(&fc->lock); 609 spin_lock_init(&fc->bg_lock); 610 init_rwsem(&fc->killsb); 611 refcount_set(&fc->count, 1); 612 atomic_set(&fc->dev_count, 1); 613 init_waitqueue_head(&fc->blocked_waitq); 614 init_waitqueue_head(&fc->reserved_req_waitq); 615 fuse_iqueue_init(&fc->iq); 616 INIT_LIST_HEAD(&fc->bg_queue); 617 INIT_LIST_HEAD(&fc->entry); 618 INIT_LIST_HEAD(&fc->devices); 619 atomic_set(&fc->num_waiting, 0); 620 fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND; 621 fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD; 622 fc->khctr = 0; 623 fc->polled_files = RB_ROOT; 624 fc->blocked = 0; 625 fc->initialized = 0; 626 fc->connected = 1; 627 fc->attr_version = 1; 628 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key)); 629 fc->pid_ns = get_pid_ns(task_active_pid_ns(current)); 630 fc->user_ns = get_user_ns(user_ns); 631 fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ; 632 } 633 EXPORT_SYMBOL_GPL(fuse_conn_init); 634 635 void fuse_conn_put(struct fuse_conn *fc) 636 { 637 if (refcount_dec_and_test(&fc->count)) { 638 if (fc->destroy_req) 639 fuse_request_free(fc->destroy_req); 640 put_pid_ns(fc->pid_ns); 641 put_user_ns(fc->user_ns); 642 fc->release(fc); 643 } 644 } 645 EXPORT_SYMBOL_GPL(fuse_conn_put); 646 647 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc) 648 { 649 refcount_inc(&fc->count); 650 return fc; 651 } 652 EXPORT_SYMBOL_GPL(fuse_conn_get); 653 654 static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode) 655 { 656 struct fuse_attr attr; 657 memset(&attr, 0, sizeof(attr)); 658 659 attr.mode = mode; 660 attr.ino = FUSE_ROOT_ID; 661 attr.nlink = 1; 662 return fuse_iget(sb, 1, 0, &attr, 0, 0); 663 } 664 665 struct fuse_inode_handle { 666 u64 nodeid; 667 u32 generation; 668 }; 669 670 static struct dentry *fuse_get_dentry(struct super_block *sb, 671 struct fuse_inode_handle *handle) 672 { 673 struct fuse_conn *fc = get_fuse_conn_super(sb); 674 struct inode *inode; 675 struct dentry *entry; 676 int err = -ESTALE; 677 678 if (handle->nodeid == 0) 679 goto out_err; 680 681 inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid); 682 if (!inode) { 683 struct fuse_entry_out outarg; 684 const struct qstr name = QSTR_INIT(".", 1); 685 686 if (!fc->export_support) 687 goto out_err; 688 689 err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg, 690 &inode); 691 if (err && err != -ENOENT) 692 goto out_err; 693 if (err || !inode) { 694 err = -ESTALE; 695 goto out_err; 696 } 697 err = -EIO; 698 if (get_node_id(inode) != handle->nodeid) 699 goto out_iput; 700 } 701 err = -ESTALE; 702 if (inode->i_generation != handle->generation) 703 goto out_iput; 704 705 entry = d_obtain_alias(inode); 706 if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID) 707 fuse_invalidate_entry_cache(entry); 708 709 return entry; 710 711 out_iput: 712 iput(inode); 713 out_err: 714 return ERR_PTR(err); 715 } 716 717 static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len, 718 struct inode *parent) 719 { 720 int len = parent ? 6 : 3; 721 u64 nodeid; 722 u32 generation; 723 724 if (*max_len < len) { 725 *max_len = len; 726 return FILEID_INVALID; 727 } 728 729 nodeid = get_fuse_inode(inode)->nodeid; 730 generation = inode->i_generation; 731 732 fh[0] = (u32)(nodeid >> 32); 733 fh[1] = (u32)(nodeid & 0xffffffff); 734 fh[2] = generation; 735 736 if (parent) { 737 nodeid = get_fuse_inode(parent)->nodeid; 738 generation = parent->i_generation; 739 740 fh[3] = (u32)(nodeid >> 32); 741 fh[4] = (u32)(nodeid & 0xffffffff); 742 fh[5] = generation; 743 } 744 745 *max_len = len; 746 return parent ? 0x82 : 0x81; 747 } 748 749 static struct dentry *fuse_fh_to_dentry(struct super_block *sb, 750 struct fid *fid, int fh_len, int fh_type) 751 { 752 struct fuse_inode_handle handle; 753 754 if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3) 755 return NULL; 756 757 handle.nodeid = (u64) fid->raw[0] << 32; 758 handle.nodeid |= (u64) fid->raw[1]; 759 handle.generation = fid->raw[2]; 760 return fuse_get_dentry(sb, &handle); 761 } 762 763 static struct dentry *fuse_fh_to_parent(struct super_block *sb, 764 struct fid *fid, int fh_len, int fh_type) 765 { 766 struct fuse_inode_handle parent; 767 768 if (fh_type != 0x82 || fh_len < 6) 769 return NULL; 770 771 parent.nodeid = (u64) fid->raw[3] << 32; 772 parent.nodeid |= (u64) fid->raw[4]; 773 parent.generation = fid->raw[5]; 774 return fuse_get_dentry(sb, &parent); 775 } 776 777 static struct dentry *fuse_get_parent(struct dentry *child) 778 { 779 struct inode *child_inode = d_inode(child); 780 struct fuse_conn *fc = get_fuse_conn(child_inode); 781 struct inode *inode; 782 struct dentry *parent; 783 struct fuse_entry_out outarg; 784 const struct qstr name = QSTR_INIT("..", 2); 785 int err; 786 787 if (!fc->export_support) 788 return ERR_PTR(-ESTALE); 789 790 err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode), 791 &name, &outarg, &inode); 792 if (err) { 793 if (err == -ENOENT) 794 return ERR_PTR(-ESTALE); 795 return ERR_PTR(err); 796 } 797 798 parent = d_obtain_alias(inode); 799 if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID) 800 fuse_invalidate_entry_cache(parent); 801 802 return parent; 803 } 804 805 static const struct export_operations fuse_export_operations = { 806 .fh_to_dentry = fuse_fh_to_dentry, 807 .fh_to_parent = fuse_fh_to_parent, 808 .encode_fh = fuse_encode_fh, 809 .get_parent = fuse_get_parent, 810 }; 811 812 static const struct super_operations fuse_super_operations = { 813 .alloc_inode = fuse_alloc_inode, 814 .destroy_inode = fuse_destroy_inode, 815 .evict_inode = fuse_evict_inode, 816 .write_inode = fuse_write_inode, 817 .drop_inode = generic_delete_inode, 818 .remount_fs = fuse_remount_fs, 819 .put_super = fuse_put_super, 820 .umount_begin = fuse_umount_begin, 821 .statfs = fuse_statfs, 822 .show_options = fuse_show_options, 823 }; 824 825 static void sanitize_global_limit(unsigned *limit) 826 { 827 if (*limit == 0) 828 *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 829 sizeof(struct fuse_req); 830 831 if (*limit >= 1 << 16) 832 *limit = (1 << 16) - 1; 833 } 834 835 static int set_global_limit(const char *val, const struct kernel_param *kp) 836 { 837 int rv; 838 839 rv = param_set_uint(val, kp); 840 if (rv) 841 return rv; 842 843 sanitize_global_limit((unsigned *)kp->arg); 844 845 return 0; 846 } 847 848 static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg) 849 { 850 int cap_sys_admin = capable(CAP_SYS_ADMIN); 851 852 if (arg->minor < 13) 853 return; 854 855 sanitize_global_limit(&max_user_bgreq); 856 sanitize_global_limit(&max_user_congthresh); 857 858 spin_lock(&fc->bg_lock); 859 if (arg->max_background) { 860 fc->max_background = arg->max_background; 861 862 if (!cap_sys_admin && fc->max_background > max_user_bgreq) 863 fc->max_background = max_user_bgreq; 864 } 865 if (arg->congestion_threshold) { 866 fc->congestion_threshold = arg->congestion_threshold; 867 868 if (!cap_sys_admin && 869 fc->congestion_threshold > max_user_congthresh) 870 fc->congestion_threshold = max_user_congthresh; 871 } 872 spin_unlock(&fc->bg_lock); 873 } 874 875 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) 876 { 877 struct fuse_init_out *arg = &req->misc.init_out; 878 879 if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION) 880 fc->conn_error = 1; 881 else { 882 unsigned long ra_pages; 883 884 process_init_limits(fc, arg); 885 886 if (arg->minor >= 6) { 887 ra_pages = arg->max_readahead / PAGE_SIZE; 888 if (arg->flags & FUSE_ASYNC_READ) 889 fc->async_read = 1; 890 if (!(arg->flags & FUSE_POSIX_LOCKS)) 891 fc->no_lock = 1; 892 if (arg->minor >= 17) { 893 if (!(arg->flags & FUSE_FLOCK_LOCKS)) 894 fc->no_flock = 1; 895 } else { 896 if (!(arg->flags & FUSE_POSIX_LOCKS)) 897 fc->no_flock = 1; 898 } 899 if (arg->flags & FUSE_ATOMIC_O_TRUNC) 900 fc->atomic_o_trunc = 1; 901 if (arg->minor >= 9) { 902 /* LOOKUP has dependency on proto version */ 903 if (arg->flags & FUSE_EXPORT_SUPPORT) 904 fc->export_support = 1; 905 } 906 if (arg->flags & FUSE_BIG_WRITES) 907 fc->big_writes = 1; 908 if (arg->flags & FUSE_DONT_MASK) 909 fc->dont_mask = 1; 910 if (arg->flags & FUSE_AUTO_INVAL_DATA) 911 fc->auto_inval_data = 1; 912 if (arg->flags & FUSE_DO_READDIRPLUS) { 913 fc->do_readdirplus = 1; 914 if (arg->flags & FUSE_READDIRPLUS_AUTO) 915 fc->readdirplus_auto = 1; 916 } 917 if (arg->flags & FUSE_ASYNC_DIO) 918 fc->async_dio = 1; 919 if (arg->flags & FUSE_WRITEBACK_CACHE) 920 fc->writeback_cache = 1; 921 if (arg->flags & FUSE_PARALLEL_DIROPS) 922 fc->parallel_dirops = 1; 923 if (arg->flags & FUSE_HANDLE_KILLPRIV) 924 fc->handle_killpriv = 1; 925 if (arg->time_gran && arg->time_gran <= 1000000000) 926 fc->sb->s_time_gran = arg->time_gran; 927 if ((arg->flags & FUSE_POSIX_ACL)) { 928 fc->default_permissions = 1; 929 fc->posix_acl = 1; 930 fc->sb->s_xattr = fuse_acl_xattr_handlers; 931 } 932 if (arg->flags & FUSE_CACHE_SYMLINKS) 933 fc->cache_symlinks = 1; 934 if (arg->flags & FUSE_ABORT_ERROR) 935 fc->abort_err = 1; 936 if (arg->flags & FUSE_MAX_PAGES) { 937 fc->max_pages = 938 min_t(unsigned int, FUSE_MAX_MAX_PAGES, 939 max_t(unsigned int, arg->max_pages, 1)); 940 } 941 } else { 942 ra_pages = fc->max_read / PAGE_SIZE; 943 fc->no_lock = 1; 944 fc->no_flock = 1; 945 } 946 947 fc->sb->s_bdi->ra_pages = 948 min(fc->sb->s_bdi->ra_pages, ra_pages); 949 fc->minor = arg->minor; 950 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write; 951 fc->max_write = max_t(unsigned, 4096, fc->max_write); 952 fc->conn_init = 1; 953 } 954 fuse_set_initialized(fc); 955 wake_up_all(&fc->blocked_waitq); 956 } 957 958 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) 959 { 960 struct fuse_init_in *arg = &req->misc.init_in; 961 962 arg->major = FUSE_KERNEL_VERSION; 963 arg->minor = FUSE_KERNEL_MINOR_VERSION; 964 arg->max_readahead = fc->sb->s_bdi->ra_pages * PAGE_SIZE; 965 arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC | 966 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK | 967 FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ | 968 FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA | 969 FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO | 970 FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT | 971 FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL | 972 FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS; 973 req->in.h.opcode = FUSE_INIT; 974 req->in.numargs = 1; 975 req->in.args[0].size = sizeof(*arg); 976 req->in.args[0].value = arg; 977 req->out.numargs = 1; 978 /* Variable length argument used for backward compatibility 979 with interface version < 7.5. Rest of init_out is zeroed 980 by do_get_request(), so a short reply is not a problem */ 981 req->out.argvar = 1; 982 req->out.args[0].size = sizeof(struct fuse_init_out); 983 req->out.args[0].value = &req->misc.init_out; 984 req->end = process_init_reply; 985 fuse_request_send_background(fc, req); 986 } 987 988 static void fuse_free_conn(struct fuse_conn *fc) 989 { 990 WARN_ON(!list_empty(&fc->devices)); 991 kfree_rcu(fc, rcu); 992 } 993 994 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb) 995 { 996 int err; 997 char *suffix = ""; 998 999 if (sb->s_bdev) { 1000 suffix = "-fuseblk"; 1001 /* 1002 * sb->s_bdi points to blkdev's bdi however we want to redirect 1003 * it to our private bdi... 1004 */ 1005 bdi_put(sb->s_bdi); 1006 sb->s_bdi = &noop_backing_dev_info; 1007 } 1008 err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev), 1009 MINOR(fc->dev), suffix); 1010 if (err) 1011 return err; 1012 1013 sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_SIZE; 1014 /* fuse does it's own writeback accounting */ 1015 sb->s_bdi->capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT; 1016 1017 /* 1018 * For a single fuse filesystem use max 1% of dirty + 1019 * writeback threshold. 1020 * 1021 * This gives about 1M of write buffer for memory maps on a 1022 * machine with 1G and 10% dirty_ratio, which should be more 1023 * than enough. 1024 * 1025 * Privileged users can raise it by writing to 1026 * 1027 * /sys/class/bdi/<bdi>/max_ratio 1028 */ 1029 bdi_set_max_ratio(sb->s_bdi, 1); 1030 1031 return 0; 1032 } 1033 1034 struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc) 1035 { 1036 struct fuse_dev *fud; 1037 struct list_head *pq; 1038 1039 fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL); 1040 if (!fud) 1041 return NULL; 1042 1043 pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL); 1044 if (!pq) { 1045 kfree(fud); 1046 return NULL; 1047 } 1048 1049 fud->pq.processing = pq; 1050 fud->fc = fuse_conn_get(fc); 1051 fuse_pqueue_init(&fud->pq); 1052 1053 spin_lock(&fc->lock); 1054 list_add_tail(&fud->entry, &fc->devices); 1055 spin_unlock(&fc->lock); 1056 1057 return fud; 1058 } 1059 EXPORT_SYMBOL_GPL(fuse_dev_alloc); 1060 1061 void fuse_dev_free(struct fuse_dev *fud) 1062 { 1063 struct fuse_conn *fc = fud->fc; 1064 1065 if (fc) { 1066 spin_lock(&fc->lock); 1067 list_del(&fud->entry); 1068 spin_unlock(&fc->lock); 1069 1070 fuse_conn_put(fc); 1071 } 1072 kfree(fud->pq.processing); 1073 kfree(fud); 1074 } 1075 EXPORT_SYMBOL_GPL(fuse_dev_free); 1076 1077 static int fuse_fill_super(struct super_block *sb, void *data, int silent) 1078 { 1079 struct fuse_dev *fud; 1080 struct fuse_conn *fc; 1081 struct inode *root; 1082 struct fuse_mount_data d; 1083 struct file *file; 1084 struct dentry *root_dentry; 1085 struct fuse_req *init_req; 1086 int err; 1087 int is_bdev = sb->s_bdev != NULL; 1088 1089 err = -EINVAL; 1090 if (sb->s_flags & SB_MANDLOCK) 1091 goto err; 1092 1093 sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION); 1094 1095 if (!parse_fuse_opt(data, &d, is_bdev, sb->s_user_ns)) 1096 goto err; 1097 1098 if (is_bdev) { 1099 #ifdef CONFIG_BLOCK 1100 err = -EINVAL; 1101 if (!sb_set_blocksize(sb, d.blksize)) 1102 goto err; 1103 #endif 1104 } else { 1105 sb->s_blocksize = PAGE_SIZE; 1106 sb->s_blocksize_bits = PAGE_SHIFT; 1107 } 1108 sb->s_magic = FUSE_SUPER_MAGIC; 1109 sb->s_op = &fuse_super_operations; 1110 sb->s_xattr = fuse_xattr_handlers; 1111 sb->s_maxbytes = MAX_LFS_FILESIZE; 1112 sb->s_time_gran = 1; 1113 sb->s_export_op = &fuse_export_operations; 1114 sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE; 1115 if (sb->s_user_ns != &init_user_ns) 1116 sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER; 1117 1118 file = fget(d.fd); 1119 err = -EINVAL; 1120 if (!file) 1121 goto err; 1122 1123 /* 1124 * Require mount to happen from the same user namespace which 1125 * opened /dev/fuse to prevent potential attacks. 1126 */ 1127 if (file->f_op != &fuse_dev_operations || 1128 file->f_cred->user_ns != sb->s_user_ns) 1129 goto err_fput; 1130 1131 /* 1132 * If we are not in the initial user namespace posix 1133 * acls must be translated. 1134 */ 1135 if (sb->s_user_ns != &init_user_ns) 1136 sb->s_xattr = fuse_no_acl_xattr_handlers; 1137 1138 fc = kmalloc(sizeof(*fc), GFP_KERNEL); 1139 err = -ENOMEM; 1140 if (!fc) 1141 goto err_fput; 1142 1143 fuse_conn_init(fc, sb->s_user_ns); 1144 fc->release = fuse_free_conn; 1145 1146 fud = fuse_dev_alloc(fc); 1147 if (!fud) 1148 goto err_put_conn; 1149 1150 fc->dev = sb->s_dev; 1151 fc->sb = sb; 1152 err = fuse_bdi_init(fc, sb); 1153 if (err) 1154 goto err_dev_free; 1155 1156 /* Handle umasking inside the fuse code */ 1157 if (sb->s_flags & SB_POSIXACL) 1158 fc->dont_mask = 1; 1159 sb->s_flags |= SB_POSIXACL; 1160 1161 fc->default_permissions = d.default_permissions; 1162 fc->allow_other = d.allow_other; 1163 fc->user_id = d.user_id; 1164 fc->group_id = d.group_id; 1165 fc->max_read = max_t(unsigned, 4096, d.max_read); 1166 1167 /* Used by get_root_inode() */ 1168 sb->s_fs_info = fc; 1169 1170 err = -ENOMEM; 1171 root = fuse_get_root_inode(sb, d.rootmode); 1172 sb->s_d_op = &fuse_root_dentry_operations; 1173 root_dentry = d_make_root(root); 1174 if (!root_dentry) 1175 goto err_dev_free; 1176 /* Root dentry doesn't have .d_revalidate */ 1177 sb->s_d_op = &fuse_dentry_operations; 1178 1179 init_req = fuse_request_alloc(0); 1180 if (!init_req) 1181 goto err_put_root; 1182 __set_bit(FR_BACKGROUND, &init_req->flags); 1183 1184 if (is_bdev) { 1185 fc->destroy_req = fuse_request_alloc(0); 1186 if (!fc->destroy_req) 1187 goto err_free_init_req; 1188 } 1189 1190 mutex_lock(&fuse_mutex); 1191 err = -EINVAL; 1192 if (file->private_data) 1193 goto err_unlock; 1194 1195 err = fuse_ctl_add_conn(fc); 1196 if (err) 1197 goto err_unlock; 1198 1199 list_add_tail(&fc->entry, &fuse_conn_list); 1200 sb->s_root = root_dentry; 1201 file->private_data = fud; 1202 mutex_unlock(&fuse_mutex); 1203 /* 1204 * atomic_dec_and_test() in fput() provides the necessary 1205 * memory barrier for file->private_data to be visible on all 1206 * CPUs after this 1207 */ 1208 fput(file); 1209 1210 fuse_send_init(fc, init_req); 1211 1212 return 0; 1213 1214 err_unlock: 1215 mutex_unlock(&fuse_mutex); 1216 err_free_init_req: 1217 fuse_request_free(init_req); 1218 err_put_root: 1219 dput(root_dentry); 1220 err_dev_free: 1221 fuse_dev_free(fud); 1222 err_put_conn: 1223 fuse_conn_put(fc); 1224 sb->s_fs_info = NULL; 1225 err_fput: 1226 fput(file); 1227 err: 1228 return err; 1229 } 1230 1231 static struct dentry *fuse_mount(struct file_system_type *fs_type, 1232 int flags, const char *dev_name, 1233 void *raw_data) 1234 { 1235 return mount_nodev(fs_type, flags, raw_data, fuse_fill_super); 1236 } 1237 1238 static void fuse_sb_destroy(struct super_block *sb) 1239 { 1240 struct fuse_conn *fc = get_fuse_conn_super(sb); 1241 1242 if (fc) { 1243 fuse_send_destroy(fc); 1244 1245 fuse_abort_conn(fc, false); 1246 fuse_wait_aborted(fc); 1247 1248 down_write(&fc->killsb); 1249 fc->sb = NULL; 1250 up_write(&fc->killsb); 1251 } 1252 } 1253 1254 static void fuse_kill_sb_anon(struct super_block *sb) 1255 { 1256 fuse_sb_destroy(sb); 1257 kill_anon_super(sb); 1258 } 1259 1260 static struct file_system_type fuse_fs_type = { 1261 .owner = THIS_MODULE, 1262 .name = "fuse", 1263 .fs_flags = FS_HAS_SUBTYPE | FS_USERNS_MOUNT, 1264 .mount = fuse_mount, 1265 .kill_sb = fuse_kill_sb_anon, 1266 }; 1267 MODULE_ALIAS_FS("fuse"); 1268 1269 #ifdef CONFIG_BLOCK 1270 static struct dentry *fuse_mount_blk(struct file_system_type *fs_type, 1271 int flags, const char *dev_name, 1272 void *raw_data) 1273 { 1274 return mount_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super); 1275 } 1276 1277 static void fuse_kill_sb_blk(struct super_block *sb) 1278 { 1279 fuse_sb_destroy(sb); 1280 kill_block_super(sb); 1281 } 1282 1283 static struct file_system_type fuseblk_fs_type = { 1284 .owner = THIS_MODULE, 1285 .name = "fuseblk", 1286 .mount = fuse_mount_blk, 1287 .kill_sb = fuse_kill_sb_blk, 1288 .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE, 1289 }; 1290 MODULE_ALIAS_FS("fuseblk"); 1291 1292 static inline int register_fuseblk(void) 1293 { 1294 return register_filesystem(&fuseblk_fs_type); 1295 } 1296 1297 static inline void unregister_fuseblk(void) 1298 { 1299 unregister_filesystem(&fuseblk_fs_type); 1300 } 1301 #else 1302 static inline int register_fuseblk(void) 1303 { 1304 return 0; 1305 } 1306 1307 static inline void unregister_fuseblk(void) 1308 { 1309 } 1310 #endif 1311 1312 static void fuse_inode_init_once(void *foo) 1313 { 1314 struct inode *inode = foo; 1315 1316 inode_init_once(inode); 1317 } 1318 1319 static int __init fuse_fs_init(void) 1320 { 1321 int err; 1322 1323 fuse_inode_cachep = kmem_cache_create("fuse_inode", 1324 sizeof(struct fuse_inode), 0, 1325 SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT, 1326 fuse_inode_init_once); 1327 err = -ENOMEM; 1328 if (!fuse_inode_cachep) 1329 goto out; 1330 1331 err = register_fuseblk(); 1332 if (err) 1333 goto out2; 1334 1335 err = register_filesystem(&fuse_fs_type); 1336 if (err) 1337 goto out3; 1338 1339 return 0; 1340 1341 out3: 1342 unregister_fuseblk(); 1343 out2: 1344 kmem_cache_destroy(fuse_inode_cachep); 1345 out: 1346 return err; 1347 } 1348 1349 static void fuse_fs_cleanup(void) 1350 { 1351 unregister_filesystem(&fuse_fs_type); 1352 unregister_fuseblk(); 1353 1354 /* 1355 * Make sure all delayed rcu free inodes are flushed before we 1356 * destroy cache. 1357 */ 1358 rcu_barrier(); 1359 kmem_cache_destroy(fuse_inode_cachep); 1360 } 1361 1362 static struct kobject *fuse_kobj; 1363 1364 static int fuse_sysfs_init(void) 1365 { 1366 int err; 1367 1368 fuse_kobj = kobject_create_and_add("fuse", fs_kobj); 1369 if (!fuse_kobj) { 1370 err = -ENOMEM; 1371 goto out_err; 1372 } 1373 1374 err = sysfs_create_mount_point(fuse_kobj, "connections"); 1375 if (err) 1376 goto out_fuse_unregister; 1377 1378 return 0; 1379 1380 out_fuse_unregister: 1381 kobject_put(fuse_kobj); 1382 out_err: 1383 return err; 1384 } 1385 1386 static void fuse_sysfs_cleanup(void) 1387 { 1388 sysfs_remove_mount_point(fuse_kobj, "connections"); 1389 kobject_put(fuse_kobj); 1390 } 1391 1392 static int __init fuse_init(void) 1393 { 1394 int res; 1395 1396 printk(KERN_INFO "fuse init (API version %i.%i)\n", 1397 FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION); 1398 1399 INIT_LIST_HEAD(&fuse_conn_list); 1400 res = fuse_fs_init(); 1401 if (res) 1402 goto err; 1403 1404 res = fuse_dev_init(); 1405 if (res) 1406 goto err_fs_cleanup; 1407 1408 res = fuse_sysfs_init(); 1409 if (res) 1410 goto err_dev_cleanup; 1411 1412 res = fuse_ctl_init(); 1413 if (res) 1414 goto err_sysfs_cleanup; 1415 1416 sanitize_global_limit(&max_user_bgreq); 1417 sanitize_global_limit(&max_user_congthresh); 1418 1419 return 0; 1420 1421 err_sysfs_cleanup: 1422 fuse_sysfs_cleanup(); 1423 err_dev_cleanup: 1424 fuse_dev_cleanup(); 1425 err_fs_cleanup: 1426 fuse_fs_cleanup(); 1427 err: 1428 return res; 1429 } 1430 1431 static void __exit fuse_exit(void) 1432 { 1433 printk(KERN_DEBUG "fuse exit\n"); 1434 1435 fuse_ctl_cleanup(); 1436 fuse_sysfs_cleanup(); 1437 fuse_fs_cleanup(); 1438 fuse_dev_cleanup(); 1439 } 1440 1441 module_init(fuse_init); 1442 module_exit(fuse_exit); 1443