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 } 632 EXPORT_SYMBOL_GPL(fuse_conn_init); 633 634 void fuse_conn_put(struct fuse_conn *fc) 635 { 636 if (refcount_dec_and_test(&fc->count)) { 637 if (fc->destroy_req) 638 fuse_request_free(fc->destroy_req); 639 put_pid_ns(fc->pid_ns); 640 put_user_ns(fc->user_ns); 641 fc->release(fc); 642 } 643 } 644 EXPORT_SYMBOL_GPL(fuse_conn_put); 645 646 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc) 647 { 648 refcount_inc(&fc->count); 649 return fc; 650 } 651 EXPORT_SYMBOL_GPL(fuse_conn_get); 652 653 static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode) 654 { 655 struct fuse_attr attr; 656 memset(&attr, 0, sizeof(attr)); 657 658 attr.mode = mode; 659 attr.ino = FUSE_ROOT_ID; 660 attr.nlink = 1; 661 return fuse_iget(sb, 1, 0, &attr, 0, 0); 662 } 663 664 struct fuse_inode_handle { 665 u64 nodeid; 666 u32 generation; 667 }; 668 669 static struct dentry *fuse_get_dentry(struct super_block *sb, 670 struct fuse_inode_handle *handle) 671 { 672 struct fuse_conn *fc = get_fuse_conn_super(sb); 673 struct inode *inode; 674 struct dentry *entry; 675 int err = -ESTALE; 676 677 if (handle->nodeid == 0) 678 goto out_err; 679 680 inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid); 681 if (!inode) { 682 struct fuse_entry_out outarg; 683 const struct qstr name = QSTR_INIT(".", 1); 684 685 if (!fc->export_support) 686 goto out_err; 687 688 err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg, 689 &inode); 690 if (err && err != -ENOENT) 691 goto out_err; 692 if (err || !inode) { 693 err = -ESTALE; 694 goto out_err; 695 } 696 err = -EIO; 697 if (get_node_id(inode) != handle->nodeid) 698 goto out_iput; 699 } 700 err = -ESTALE; 701 if (inode->i_generation != handle->generation) 702 goto out_iput; 703 704 entry = d_obtain_alias(inode); 705 if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID) 706 fuse_invalidate_entry_cache(entry); 707 708 return entry; 709 710 out_iput: 711 iput(inode); 712 out_err: 713 return ERR_PTR(err); 714 } 715 716 static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len, 717 struct inode *parent) 718 { 719 int len = parent ? 6 : 3; 720 u64 nodeid; 721 u32 generation; 722 723 if (*max_len < len) { 724 *max_len = len; 725 return FILEID_INVALID; 726 } 727 728 nodeid = get_fuse_inode(inode)->nodeid; 729 generation = inode->i_generation; 730 731 fh[0] = (u32)(nodeid >> 32); 732 fh[1] = (u32)(nodeid & 0xffffffff); 733 fh[2] = generation; 734 735 if (parent) { 736 nodeid = get_fuse_inode(parent)->nodeid; 737 generation = parent->i_generation; 738 739 fh[3] = (u32)(nodeid >> 32); 740 fh[4] = (u32)(nodeid & 0xffffffff); 741 fh[5] = generation; 742 } 743 744 *max_len = len; 745 return parent ? 0x82 : 0x81; 746 } 747 748 static struct dentry *fuse_fh_to_dentry(struct super_block *sb, 749 struct fid *fid, int fh_len, int fh_type) 750 { 751 struct fuse_inode_handle handle; 752 753 if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3) 754 return NULL; 755 756 handle.nodeid = (u64) fid->raw[0] << 32; 757 handle.nodeid |= (u64) fid->raw[1]; 758 handle.generation = fid->raw[2]; 759 return fuse_get_dentry(sb, &handle); 760 } 761 762 static struct dentry *fuse_fh_to_parent(struct super_block *sb, 763 struct fid *fid, int fh_len, int fh_type) 764 { 765 struct fuse_inode_handle parent; 766 767 if (fh_type != 0x82 || fh_len < 6) 768 return NULL; 769 770 parent.nodeid = (u64) fid->raw[3] << 32; 771 parent.nodeid |= (u64) fid->raw[4]; 772 parent.generation = fid->raw[5]; 773 return fuse_get_dentry(sb, &parent); 774 } 775 776 static struct dentry *fuse_get_parent(struct dentry *child) 777 { 778 struct inode *child_inode = d_inode(child); 779 struct fuse_conn *fc = get_fuse_conn(child_inode); 780 struct inode *inode; 781 struct dentry *parent; 782 struct fuse_entry_out outarg; 783 const struct qstr name = QSTR_INIT("..", 2); 784 int err; 785 786 if (!fc->export_support) 787 return ERR_PTR(-ESTALE); 788 789 err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode), 790 &name, &outarg, &inode); 791 if (err) { 792 if (err == -ENOENT) 793 return ERR_PTR(-ESTALE); 794 return ERR_PTR(err); 795 } 796 797 parent = d_obtain_alias(inode); 798 if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID) 799 fuse_invalidate_entry_cache(parent); 800 801 return parent; 802 } 803 804 static const struct export_operations fuse_export_operations = { 805 .fh_to_dentry = fuse_fh_to_dentry, 806 .fh_to_parent = fuse_fh_to_parent, 807 .encode_fh = fuse_encode_fh, 808 .get_parent = fuse_get_parent, 809 }; 810 811 static const struct super_operations fuse_super_operations = { 812 .alloc_inode = fuse_alloc_inode, 813 .destroy_inode = fuse_destroy_inode, 814 .evict_inode = fuse_evict_inode, 815 .write_inode = fuse_write_inode, 816 .drop_inode = generic_delete_inode, 817 .remount_fs = fuse_remount_fs, 818 .put_super = fuse_put_super, 819 .umount_begin = fuse_umount_begin, 820 .statfs = fuse_statfs, 821 .show_options = fuse_show_options, 822 }; 823 824 static void sanitize_global_limit(unsigned *limit) 825 { 826 if (*limit == 0) 827 *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 828 sizeof(struct fuse_req); 829 830 if (*limit >= 1 << 16) 831 *limit = (1 << 16) - 1; 832 } 833 834 static int set_global_limit(const char *val, const struct kernel_param *kp) 835 { 836 int rv; 837 838 rv = param_set_uint(val, kp); 839 if (rv) 840 return rv; 841 842 sanitize_global_limit((unsigned *)kp->arg); 843 844 return 0; 845 } 846 847 static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg) 848 { 849 int cap_sys_admin = capable(CAP_SYS_ADMIN); 850 851 if (arg->minor < 13) 852 return; 853 854 sanitize_global_limit(&max_user_bgreq); 855 sanitize_global_limit(&max_user_congthresh); 856 857 spin_lock(&fc->bg_lock); 858 if (arg->max_background) { 859 fc->max_background = arg->max_background; 860 861 if (!cap_sys_admin && fc->max_background > max_user_bgreq) 862 fc->max_background = max_user_bgreq; 863 } 864 if (arg->congestion_threshold) { 865 fc->congestion_threshold = arg->congestion_threshold; 866 867 if (!cap_sys_admin && 868 fc->congestion_threshold > max_user_congthresh) 869 fc->congestion_threshold = max_user_congthresh; 870 } 871 spin_unlock(&fc->bg_lock); 872 } 873 874 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) 875 { 876 struct fuse_init_out *arg = &req->misc.init_out; 877 878 if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION) 879 fc->conn_error = 1; 880 else { 881 unsigned long ra_pages; 882 883 process_init_limits(fc, arg); 884 885 if (arg->minor >= 6) { 886 ra_pages = arg->max_readahead / PAGE_SIZE; 887 if (arg->flags & FUSE_ASYNC_READ) 888 fc->async_read = 1; 889 if (!(arg->flags & FUSE_POSIX_LOCKS)) 890 fc->no_lock = 1; 891 if (arg->minor >= 17) { 892 if (!(arg->flags & FUSE_FLOCK_LOCKS)) 893 fc->no_flock = 1; 894 } else { 895 if (!(arg->flags & FUSE_POSIX_LOCKS)) 896 fc->no_flock = 1; 897 } 898 if (arg->flags & FUSE_ATOMIC_O_TRUNC) 899 fc->atomic_o_trunc = 1; 900 if (arg->minor >= 9) { 901 /* LOOKUP has dependency on proto version */ 902 if (arg->flags & FUSE_EXPORT_SUPPORT) 903 fc->export_support = 1; 904 } 905 if (arg->flags & FUSE_BIG_WRITES) 906 fc->big_writes = 1; 907 if (arg->flags & FUSE_DONT_MASK) 908 fc->dont_mask = 1; 909 if (arg->flags & FUSE_AUTO_INVAL_DATA) 910 fc->auto_inval_data = 1; 911 if (arg->flags & FUSE_DO_READDIRPLUS) { 912 fc->do_readdirplus = 1; 913 if (arg->flags & FUSE_READDIRPLUS_AUTO) 914 fc->readdirplus_auto = 1; 915 } 916 if (arg->flags & FUSE_ASYNC_DIO) 917 fc->async_dio = 1; 918 if (arg->flags & FUSE_WRITEBACK_CACHE) 919 fc->writeback_cache = 1; 920 if (arg->flags & FUSE_PARALLEL_DIROPS) 921 fc->parallel_dirops = 1; 922 if (arg->flags & FUSE_HANDLE_KILLPRIV) 923 fc->handle_killpriv = 1; 924 if (arg->time_gran && arg->time_gran <= 1000000000) 925 fc->sb->s_time_gran = arg->time_gran; 926 if ((arg->flags & FUSE_POSIX_ACL)) { 927 fc->default_permissions = 1; 928 fc->posix_acl = 1; 929 fc->sb->s_xattr = fuse_acl_xattr_handlers; 930 } 931 if (arg->flags & FUSE_CACHE_SYMLINKS) 932 fc->cache_symlinks = 1; 933 if (arg->flags & FUSE_ABORT_ERROR) 934 fc->abort_err = 1; 935 if (arg->flags & FUSE_MAX_PAGES) { 936 fc->max_pages = 937 min_t(unsigned int, FUSE_MAX_MAX_PAGES, 938 max_t(unsigned int, arg->max_pages, 1)); 939 } 940 } else { 941 ra_pages = fc->max_read / PAGE_SIZE; 942 fc->no_lock = 1; 943 fc->no_flock = 1; 944 } 945 946 fc->sb->s_bdi->ra_pages = 947 min(fc->sb->s_bdi->ra_pages, ra_pages); 948 fc->minor = arg->minor; 949 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write; 950 fc->max_write = max_t(unsigned, 4096, fc->max_write); 951 fc->conn_init = 1; 952 } 953 fuse_set_initialized(fc); 954 wake_up_all(&fc->blocked_waitq); 955 } 956 957 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) 958 { 959 struct fuse_init_in *arg = &req->misc.init_in; 960 961 arg->major = FUSE_KERNEL_VERSION; 962 arg->minor = FUSE_KERNEL_MINOR_VERSION; 963 arg->max_readahead = fc->sb->s_bdi->ra_pages * PAGE_SIZE; 964 arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC | 965 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK | 966 FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ | 967 FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA | 968 FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO | 969 FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT | 970 FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL | 971 FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS; 972 req->in.h.opcode = FUSE_INIT; 973 req->in.numargs = 1; 974 req->in.args[0].size = sizeof(*arg); 975 req->in.args[0].value = arg; 976 req->out.numargs = 1; 977 /* Variable length argument used for backward compatibility 978 with interface version < 7.5. Rest of init_out is zeroed 979 by do_get_request(), so a short reply is not a problem */ 980 req->out.argvar = 1; 981 req->out.args[0].size = sizeof(struct fuse_init_out); 982 req->out.args[0].value = &req->misc.init_out; 983 req->end = process_init_reply; 984 fuse_request_send_background(fc, req); 985 } 986 987 static void fuse_free_conn(struct fuse_conn *fc) 988 { 989 WARN_ON(!list_empty(&fc->devices)); 990 kfree_rcu(fc, rcu); 991 } 992 993 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb) 994 { 995 int err; 996 char *suffix = ""; 997 998 if (sb->s_bdev) { 999 suffix = "-fuseblk"; 1000 /* 1001 * sb->s_bdi points to blkdev's bdi however we want to redirect 1002 * it to our private bdi... 1003 */ 1004 bdi_put(sb->s_bdi); 1005 sb->s_bdi = &noop_backing_dev_info; 1006 } 1007 err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev), 1008 MINOR(fc->dev), suffix); 1009 if (err) 1010 return err; 1011 1012 sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_SIZE; 1013 /* fuse does it's own writeback accounting */ 1014 sb->s_bdi->capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT; 1015 1016 /* 1017 * For a single fuse filesystem use max 1% of dirty + 1018 * writeback threshold. 1019 * 1020 * This gives about 1M of write buffer for memory maps on a 1021 * machine with 1G and 10% dirty_ratio, which should be more 1022 * than enough. 1023 * 1024 * Privileged users can raise it by writing to 1025 * 1026 * /sys/class/bdi/<bdi>/max_ratio 1027 */ 1028 bdi_set_max_ratio(sb->s_bdi, 1); 1029 1030 return 0; 1031 } 1032 1033 struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc) 1034 { 1035 struct fuse_dev *fud; 1036 struct list_head *pq; 1037 1038 fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL); 1039 if (!fud) 1040 return NULL; 1041 1042 pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL); 1043 if (!pq) { 1044 kfree(fud); 1045 return NULL; 1046 } 1047 1048 fud->pq.processing = pq; 1049 fud->fc = fuse_conn_get(fc); 1050 fuse_pqueue_init(&fud->pq); 1051 1052 spin_lock(&fc->lock); 1053 list_add_tail(&fud->entry, &fc->devices); 1054 spin_unlock(&fc->lock); 1055 1056 return fud; 1057 } 1058 EXPORT_SYMBOL_GPL(fuse_dev_alloc); 1059 1060 void fuse_dev_free(struct fuse_dev *fud) 1061 { 1062 struct fuse_conn *fc = fud->fc; 1063 1064 if (fc) { 1065 spin_lock(&fc->lock); 1066 list_del(&fud->entry); 1067 spin_unlock(&fc->lock); 1068 1069 fuse_conn_put(fc); 1070 } 1071 kfree(fud->pq.processing); 1072 kfree(fud); 1073 } 1074 EXPORT_SYMBOL_GPL(fuse_dev_free); 1075 1076 static int fuse_fill_super(struct super_block *sb, void *data, int silent) 1077 { 1078 struct fuse_dev *fud; 1079 struct fuse_conn *fc; 1080 struct inode *root; 1081 struct fuse_mount_data d; 1082 struct file *file; 1083 struct dentry *root_dentry; 1084 struct fuse_req *init_req; 1085 int err; 1086 int is_bdev = sb->s_bdev != NULL; 1087 1088 err = -EINVAL; 1089 if (sb->s_flags & SB_MANDLOCK) 1090 goto err; 1091 1092 sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION); 1093 1094 if (!parse_fuse_opt(data, &d, is_bdev, sb->s_user_ns)) 1095 goto err; 1096 1097 if (is_bdev) { 1098 #ifdef CONFIG_BLOCK 1099 err = -EINVAL; 1100 if (!sb_set_blocksize(sb, d.blksize)) 1101 goto err; 1102 #endif 1103 } else { 1104 sb->s_blocksize = PAGE_SIZE; 1105 sb->s_blocksize_bits = PAGE_SHIFT; 1106 } 1107 sb->s_magic = FUSE_SUPER_MAGIC; 1108 sb->s_op = &fuse_super_operations; 1109 sb->s_xattr = fuse_xattr_handlers; 1110 sb->s_maxbytes = MAX_LFS_FILESIZE; 1111 sb->s_time_gran = 1; 1112 sb->s_export_op = &fuse_export_operations; 1113 sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE; 1114 if (sb->s_user_ns != &init_user_ns) 1115 sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER; 1116 1117 file = fget(d.fd); 1118 err = -EINVAL; 1119 if (!file) 1120 goto err; 1121 1122 /* 1123 * Require mount to happen from the same user namespace which 1124 * opened /dev/fuse to prevent potential attacks. 1125 */ 1126 if (file->f_op != &fuse_dev_operations || 1127 file->f_cred->user_ns != sb->s_user_ns) 1128 goto err_fput; 1129 1130 /* 1131 * If we are not in the initial user namespace posix 1132 * acls must be translated. 1133 */ 1134 if (sb->s_user_ns != &init_user_ns) 1135 sb->s_xattr = fuse_no_acl_xattr_handlers; 1136 1137 fc = kmalloc(sizeof(*fc), GFP_KERNEL); 1138 err = -ENOMEM; 1139 if (!fc) 1140 goto err_fput; 1141 1142 fuse_conn_init(fc, sb->s_user_ns); 1143 fc->release = fuse_free_conn; 1144 1145 fud = fuse_dev_alloc(fc); 1146 if (!fud) 1147 goto err_put_conn; 1148 1149 fc->dev = sb->s_dev; 1150 fc->sb = sb; 1151 err = fuse_bdi_init(fc, sb); 1152 if (err) 1153 goto err_dev_free; 1154 1155 /* Handle umasking inside the fuse code */ 1156 if (sb->s_flags & SB_POSIXACL) 1157 fc->dont_mask = 1; 1158 sb->s_flags |= SB_POSIXACL; 1159 1160 fc->default_permissions = d.default_permissions; 1161 fc->allow_other = d.allow_other; 1162 fc->user_id = d.user_id; 1163 fc->group_id = d.group_id; 1164 fc->max_read = max_t(unsigned, 4096, d.max_read); 1165 fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ; 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