1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 19 #include <linux/blkdev.h> 20 #include <linux/module.h> 21 #include <linux/buffer_head.h> 22 #include <linux/fs.h> 23 #include <linux/pagemap.h> 24 #include <linux/highmem.h> 25 #include <linux/time.h> 26 #include <linux/init.h> 27 #include <linux/seq_file.h> 28 #include <linux/string.h> 29 #include <linux/smp_lock.h> 30 #include <linux/backing-dev.h> 31 #include <linux/mount.h> 32 #include <linux/mpage.h> 33 #include <linux/swap.h> 34 #include <linux/writeback.h> 35 #include <linux/statfs.h> 36 #include <linux/compat.h> 37 #include <linux/parser.h> 38 #include <linux/ctype.h> 39 #include <linux/namei.h> 40 #include <linux/miscdevice.h> 41 #include <linux/magic.h> 42 #include "compat.h" 43 #include "ctree.h" 44 #include "disk-io.h" 45 #include "transaction.h" 46 #include "btrfs_inode.h" 47 #include "ioctl.h" 48 #include "print-tree.h" 49 #include "xattr.h" 50 #include "volumes.h" 51 #include "version.h" 52 #include "export.h" 53 #include "compression.h" 54 55 56 static struct super_operations btrfs_super_ops; 57 58 static void btrfs_put_super(struct super_block *sb) 59 { 60 struct btrfs_root *root = btrfs_sb(sb); 61 int ret; 62 63 ret = close_ctree(root); 64 sb->s_fs_info = NULL; 65 } 66 67 enum { 68 Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow, 69 Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, 70 Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_notreelog, 71 Opt_ratio, Opt_flushoncommit, Opt_err, 72 }; 73 74 static match_table_t tokens = { 75 {Opt_degraded, "degraded"}, 76 {Opt_subvol, "subvol=%s"}, 77 {Opt_device, "device=%s"}, 78 {Opt_nodatasum, "nodatasum"}, 79 {Opt_nodatacow, "nodatacow"}, 80 {Opt_nobarrier, "nobarrier"}, 81 {Opt_max_extent, "max_extent=%s"}, 82 {Opt_max_inline, "max_inline=%s"}, 83 {Opt_alloc_start, "alloc_start=%s"}, 84 {Opt_thread_pool, "thread_pool=%d"}, 85 {Opt_compress, "compress"}, 86 {Opt_ssd, "ssd"}, 87 {Opt_noacl, "noacl"}, 88 {Opt_notreelog, "notreelog"}, 89 {Opt_flushoncommit, "flushoncommit"}, 90 {Opt_ratio, "metadata_ratio=%d"}, 91 {Opt_err, NULL}, 92 }; 93 94 u64 btrfs_parse_size(char *str) 95 { 96 u64 res; 97 int mult = 1; 98 char *end; 99 char last; 100 101 res = simple_strtoul(str, &end, 10); 102 103 last = end[0]; 104 if (isalpha(last)) { 105 last = tolower(last); 106 switch (last) { 107 case 'g': 108 mult *= 1024; 109 case 'm': 110 mult *= 1024; 111 case 'k': 112 mult *= 1024; 113 } 114 res = res * mult; 115 } 116 return res; 117 } 118 119 /* 120 * Regular mount options parser. Everything that is needed only when 121 * reading in a new superblock is parsed here. 122 */ 123 int btrfs_parse_options(struct btrfs_root *root, char *options) 124 { 125 struct btrfs_fs_info *info = root->fs_info; 126 substring_t args[MAX_OPT_ARGS]; 127 char *p, *num; 128 int intarg; 129 130 if (!options) 131 return 0; 132 133 /* 134 * strsep changes the string, duplicate it because parse_options 135 * gets called twice 136 */ 137 options = kstrdup(options, GFP_NOFS); 138 if (!options) 139 return -ENOMEM; 140 141 142 while ((p = strsep(&options, ",")) != NULL) { 143 int token; 144 if (!*p) 145 continue; 146 147 token = match_token(p, tokens, args); 148 switch (token) { 149 case Opt_degraded: 150 printk(KERN_INFO "btrfs: allowing degraded mounts\n"); 151 btrfs_set_opt(info->mount_opt, DEGRADED); 152 break; 153 case Opt_subvol: 154 case Opt_device: 155 /* 156 * These are parsed by btrfs_parse_early_options 157 * and can be happily ignored here. 158 */ 159 break; 160 case Opt_nodatasum: 161 printk(KERN_INFO "btrfs: setting nodatacsum\n"); 162 btrfs_set_opt(info->mount_opt, NODATASUM); 163 break; 164 case Opt_nodatacow: 165 printk(KERN_INFO "btrfs: setting nodatacow\n"); 166 btrfs_set_opt(info->mount_opt, NODATACOW); 167 btrfs_set_opt(info->mount_opt, NODATASUM); 168 break; 169 case Opt_compress: 170 printk(KERN_INFO "btrfs: use compression\n"); 171 btrfs_set_opt(info->mount_opt, COMPRESS); 172 break; 173 case Opt_ssd: 174 printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); 175 btrfs_set_opt(info->mount_opt, SSD); 176 break; 177 case Opt_nobarrier: 178 printk(KERN_INFO "btrfs: turning off barriers\n"); 179 btrfs_set_opt(info->mount_opt, NOBARRIER); 180 break; 181 case Opt_thread_pool: 182 intarg = 0; 183 match_int(&args[0], &intarg); 184 if (intarg) { 185 info->thread_pool_size = intarg; 186 printk(KERN_INFO "btrfs: thread pool %d\n", 187 info->thread_pool_size); 188 } 189 break; 190 case Opt_max_extent: 191 num = match_strdup(&args[0]); 192 if (num) { 193 info->max_extent = btrfs_parse_size(num); 194 kfree(num); 195 196 info->max_extent = max_t(u64, 197 info->max_extent, root->sectorsize); 198 printk(KERN_INFO "btrfs: max_extent at %llu\n", 199 (unsigned long long)info->max_extent); 200 } 201 break; 202 case Opt_max_inline: 203 num = match_strdup(&args[0]); 204 if (num) { 205 info->max_inline = btrfs_parse_size(num); 206 kfree(num); 207 208 if (info->max_inline) { 209 info->max_inline = max_t(u64, 210 info->max_inline, 211 root->sectorsize); 212 } 213 printk(KERN_INFO "btrfs: max_inline at %llu\n", 214 (unsigned long long)info->max_inline); 215 } 216 break; 217 case Opt_alloc_start: 218 num = match_strdup(&args[0]); 219 if (num) { 220 info->alloc_start = btrfs_parse_size(num); 221 kfree(num); 222 printk(KERN_INFO 223 "btrfs: allocations start at %llu\n", 224 (unsigned long long)info->alloc_start); 225 } 226 break; 227 case Opt_noacl: 228 root->fs_info->sb->s_flags &= ~MS_POSIXACL; 229 break; 230 case Opt_notreelog: 231 printk(KERN_INFO "btrfs: disabling tree log\n"); 232 btrfs_set_opt(info->mount_opt, NOTREELOG); 233 break; 234 case Opt_flushoncommit: 235 printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); 236 btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); 237 break; 238 case Opt_ratio: 239 intarg = 0; 240 match_int(&args[0], &intarg); 241 if (intarg) { 242 info->metadata_ratio = intarg; 243 printk(KERN_INFO "btrfs: metadata ratio %d\n", 244 info->metadata_ratio); 245 } 246 break; 247 default: 248 break; 249 } 250 } 251 kfree(options); 252 return 0; 253 } 254 255 /* 256 * Parse mount options that are required early in the mount process. 257 * 258 * All other options will be parsed on much later in the mount process and 259 * only when we need to allocate a new super block. 260 */ 261 static int btrfs_parse_early_options(const char *options, fmode_t flags, 262 void *holder, char **subvol_name, 263 struct btrfs_fs_devices **fs_devices) 264 { 265 substring_t args[MAX_OPT_ARGS]; 266 char *opts, *p; 267 int error = 0; 268 269 if (!options) 270 goto out; 271 272 /* 273 * strsep changes the string, duplicate it because parse_options 274 * gets called twice 275 */ 276 opts = kstrdup(options, GFP_KERNEL); 277 if (!opts) 278 return -ENOMEM; 279 280 while ((p = strsep(&opts, ",")) != NULL) { 281 int token; 282 if (!*p) 283 continue; 284 285 token = match_token(p, tokens, args); 286 switch (token) { 287 case Opt_subvol: 288 *subvol_name = match_strdup(&args[0]); 289 break; 290 case Opt_device: 291 error = btrfs_scan_one_device(match_strdup(&args[0]), 292 flags, holder, fs_devices); 293 if (error) 294 goto out_free_opts; 295 break; 296 default: 297 break; 298 } 299 } 300 301 out_free_opts: 302 kfree(opts); 303 out: 304 /* 305 * If no subvolume name is specified we use the default one. Allocate 306 * a copy of the string "." here so that code later in the 307 * mount path doesn't care if it's the default volume or another one. 308 */ 309 if (!*subvol_name) { 310 *subvol_name = kstrdup(".", GFP_KERNEL); 311 if (!*subvol_name) 312 return -ENOMEM; 313 } 314 return error; 315 } 316 317 static int btrfs_fill_super(struct super_block *sb, 318 struct btrfs_fs_devices *fs_devices, 319 void *data, int silent) 320 { 321 struct inode *inode; 322 struct dentry *root_dentry; 323 struct btrfs_super_block *disk_super; 324 struct btrfs_root *tree_root; 325 struct btrfs_inode *bi; 326 int err; 327 328 sb->s_maxbytes = MAX_LFS_FILESIZE; 329 sb->s_magic = BTRFS_SUPER_MAGIC; 330 sb->s_op = &btrfs_super_ops; 331 sb->s_export_op = &btrfs_export_ops; 332 sb->s_xattr = btrfs_xattr_handlers; 333 sb->s_time_gran = 1; 334 sb->s_flags |= MS_POSIXACL; 335 336 tree_root = open_ctree(sb, fs_devices, (char *)data); 337 338 if (IS_ERR(tree_root)) { 339 printk("btrfs: open_ctree failed\n"); 340 return PTR_ERR(tree_root); 341 } 342 sb->s_fs_info = tree_root; 343 disk_super = &tree_root->fs_info->super_copy; 344 inode = btrfs_iget_locked(sb, BTRFS_FIRST_FREE_OBJECTID, 345 tree_root->fs_info->fs_root); 346 bi = BTRFS_I(inode); 347 bi->location.objectid = inode->i_ino; 348 bi->location.offset = 0; 349 bi->root = tree_root->fs_info->fs_root; 350 351 btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY); 352 353 if (!inode) { 354 err = -ENOMEM; 355 goto fail_close; 356 } 357 if (inode->i_state & I_NEW) { 358 btrfs_read_locked_inode(inode); 359 unlock_new_inode(inode); 360 } 361 362 root_dentry = d_alloc_root(inode); 363 if (!root_dentry) { 364 iput(inode); 365 err = -ENOMEM; 366 goto fail_close; 367 } 368 #if 0 369 /* this does the super kobj at the same time */ 370 err = btrfs_sysfs_add_super(tree_root->fs_info); 371 if (err) 372 goto fail_close; 373 #endif 374 375 sb->s_root = root_dentry; 376 377 save_mount_options(sb, data); 378 return 0; 379 380 fail_close: 381 close_ctree(tree_root); 382 return err; 383 } 384 385 int btrfs_sync_fs(struct super_block *sb, int wait) 386 { 387 struct btrfs_trans_handle *trans; 388 struct btrfs_root *root = btrfs_sb(sb); 389 int ret; 390 391 if (sb->s_flags & MS_RDONLY) 392 return 0; 393 394 sb->s_dirt = 0; 395 if (!wait) { 396 filemap_flush(root->fs_info->btree_inode->i_mapping); 397 return 0; 398 } 399 400 btrfs_start_delalloc_inodes(root); 401 btrfs_wait_ordered_extents(root, 0); 402 403 trans = btrfs_start_transaction(root, 1); 404 ret = btrfs_commit_transaction(trans, root); 405 sb->s_dirt = 0; 406 return ret; 407 } 408 409 static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) 410 { 411 struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); 412 struct btrfs_fs_info *info = root->fs_info; 413 414 if (btrfs_test_opt(root, DEGRADED)) 415 seq_puts(seq, ",degraded"); 416 if (btrfs_test_opt(root, NODATASUM)) 417 seq_puts(seq, ",nodatasum"); 418 if (btrfs_test_opt(root, NODATACOW)) 419 seq_puts(seq, ",nodatacow"); 420 if (btrfs_test_opt(root, NOBARRIER)) 421 seq_puts(seq, ",nobarrier"); 422 if (info->max_extent != (u64)-1) 423 seq_printf(seq, ",max_extent=%llu", 424 (unsigned long long)info->max_extent); 425 if (info->max_inline != 8192 * 1024) 426 seq_printf(seq, ",max_inline=%llu", 427 (unsigned long long)info->max_inline); 428 if (info->alloc_start != 0) 429 seq_printf(seq, ",alloc_start=%llu", 430 (unsigned long long)info->alloc_start); 431 if (info->thread_pool_size != min_t(unsigned long, 432 num_online_cpus() + 2, 8)) 433 seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); 434 if (btrfs_test_opt(root, COMPRESS)) 435 seq_puts(seq, ",compress"); 436 if (btrfs_test_opt(root, SSD)) 437 seq_puts(seq, ",ssd"); 438 if (btrfs_test_opt(root, NOTREELOG)) 439 seq_puts(seq, ",no-treelog"); 440 if (btrfs_test_opt(root, FLUSHONCOMMIT)) 441 seq_puts(seq, ",flush-on-commit"); 442 if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) 443 seq_puts(seq, ",noacl"); 444 return 0; 445 } 446 447 static void btrfs_write_super(struct super_block *sb) 448 { 449 sb->s_dirt = 0; 450 } 451 452 static int btrfs_test_super(struct super_block *s, void *data) 453 { 454 struct btrfs_fs_devices *test_fs_devices = data; 455 struct btrfs_root *root = btrfs_sb(s); 456 457 return root->fs_info->fs_devices == test_fs_devices; 458 } 459 460 /* 461 * Find a superblock for the given device / mount point. 462 * 463 * Note: This is based on get_sb_bdev from fs/super.c with a few additions 464 * for multiple device setup. Make sure to keep it in sync. 465 */ 466 static int btrfs_get_sb(struct file_system_type *fs_type, int flags, 467 const char *dev_name, void *data, struct vfsmount *mnt) 468 { 469 char *subvol_name = NULL; 470 struct block_device *bdev = NULL; 471 struct super_block *s; 472 struct dentry *root; 473 struct btrfs_fs_devices *fs_devices = NULL; 474 fmode_t mode = FMODE_READ; 475 int error = 0; 476 477 if (!(flags & MS_RDONLY)) 478 mode |= FMODE_WRITE; 479 480 error = btrfs_parse_early_options(data, mode, fs_type, 481 &subvol_name, &fs_devices); 482 if (error) 483 return error; 484 485 error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); 486 if (error) 487 goto error_free_subvol_name; 488 489 error = btrfs_open_devices(fs_devices, mode, fs_type); 490 if (error) 491 goto error_free_subvol_name; 492 493 if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { 494 error = -EACCES; 495 goto error_close_devices; 496 } 497 498 bdev = fs_devices->latest_bdev; 499 s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); 500 if (IS_ERR(s)) 501 goto error_s; 502 503 if (s->s_root) { 504 if ((flags ^ s->s_flags) & MS_RDONLY) { 505 up_write(&s->s_umount); 506 deactivate_super(s); 507 error = -EBUSY; 508 goto error_close_devices; 509 } 510 511 btrfs_close_devices(fs_devices); 512 } else { 513 char b[BDEVNAME_SIZE]; 514 515 s->s_flags = flags; 516 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); 517 error = btrfs_fill_super(s, fs_devices, data, 518 flags & MS_SILENT ? 1 : 0); 519 if (error) { 520 up_write(&s->s_umount); 521 deactivate_super(s); 522 goto error_free_subvol_name; 523 } 524 525 btrfs_sb(s)->fs_info->bdev_holder = fs_type; 526 s->s_flags |= MS_ACTIVE; 527 } 528 529 if (!strcmp(subvol_name, ".")) 530 root = dget(s->s_root); 531 else { 532 mutex_lock(&s->s_root->d_inode->i_mutex); 533 root = lookup_one_len(subvol_name, s->s_root, 534 strlen(subvol_name)); 535 mutex_unlock(&s->s_root->d_inode->i_mutex); 536 537 if (IS_ERR(root)) { 538 up_write(&s->s_umount); 539 deactivate_super(s); 540 error = PTR_ERR(root); 541 goto error_free_subvol_name; 542 } 543 if (!root->d_inode) { 544 dput(root); 545 up_write(&s->s_umount); 546 deactivate_super(s); 547 error = -ENXIO; 548 goto error_free_subvol_name; 549 } 550 } 551 552 mnt->mnt_sb = s; 553 mnt->mnt_root = root; 554 555 kfree(subvol_name); 556 return 0; 557 558 error_s: 559 error = PTR_ERR(s); 560 error_close_devices: 561 btrfs_close_devices(fs_devices); 562 error_free_subvol_name: 563 kfree(subvol_name); 564 return error; 565 } 566 567 static int btrfs_remount(struct super_block *sb, int *flags, char *data) 568 { 569 struct btrfs_root *root = btrfs_sb(sb); 570 int ret; 571 572 ret = btrfs_parse_options(root, data); 573 if (ret) 574 return -EINVAL; 575 576 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 577 return 0; 578 579 if (*flags & MS_RDONLY) { 580 sb->s_flags |= MS_RDONLY; 581 582 ret = btrfs_commit_super(root); 583 WARN_ON(ret); 584 } else { 585 if (root->fs_info->fs_devices->rw_devices == 0) 586 return -EACCES; 587 588 if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) 589 return -EINVAL; 590 591 ret = btrfs_cleanup_reloc_trees(root); 592 WARN_ON(ret); 593 594 ret = btrfs_cleanup_fs_roots(root->fs_info); 595 WARN_ON(ret); 596 597 sb->s_flags &= ~MS_RDONLY; 598 } 599 600 return 0; 601 } 602 603 static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) 604 { 605 struct btrfs_root *root = btrfs_sb(dentry->d_sb); 606 struct btrfs_super_block *disk_super = &root->fs_info->super_copy; 607 int bits = dentry->d_sb->s_blocksize_bits; 608 __be32 *fsid = (__be32 *)root->fs_info->fsid; 609 610 buf->f_namelen = BTRFS_NAME_LEN; 611 buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; 612 buf->f_bfree = buf->f_blocks - 613 (btrfs_super_bytes_used(disk_super) >> bits); 614 buf->f_bavail = buf->f_bfree; 615 buf->f_bsize = dentry->d_sb->s_blocksize; 616 buf->f_type = BTRFS_SUPER_MAGIC; 617 618 /* We treat it as constant endianness (it doesn't matter _which_) 619 because we want the fsid to come out the same whether mounted 620 on a big-endian or little-endian host */ 621 buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); 622 buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); 623 /* Mask in the root object ID too, to disambiguate subvols */ 624 buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; 625 buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; 626 627 return 0; 628 } 629 630 static struct file_system_type btrfs_fs_type = { 631 .owner = THIS_MODULE, 632 .name = "btrfs", 633 .get_sb = btrfs_get_sb, 634 .kill_sb = kill_anon_super, 635 .fs_flags = FS_REQUIRES_DEV, 636 }; 637 638 /* 639 * used by btrfsctl to scan devices when no FS is mounted 640 */ 641 static long btrfs_control_ioctl(struct file *file, unsigned int cmd, 642 unsigned long arg) 643 { 644 struct btrfs_ioctl_vol_args *vol; 645 struct btrfs_fs_devices *fs_devices; 646 int ret = -ENOTTY; 647 648 if (!capable(CAP_SYS_ADMIN)) 649 return -EPERM; 650 651 vol = memdup_user((void __user *)arg, sizeof(*vol)); 652 if (IS_ERR(vol)) 653 return PTR_ERR(vol); 654 655 switch (cmd) { 656 case BTRFS_IOC_SCAN_DEV: 657 ret = btrfs_scan_one_device(vol->name, FMODE_READ, 658 &btrfs_fs_type, &fs_devices); 659 break; 660 } 661 662 kfree(vol); 663 return ret; 664 } 665 666 static int btrfs_freeze(struct super_block *sb) 667 { 668 struct btrfs_root *root = btrfs_sb(sb); 669 mutex_lock(&root->fs_info->transaction_kthread_mutex); 670 mutex_lock(&root->fs_info->cleaner_mutex); 671 return 0; 672 } 673 674 static int btrfs_unfreeze(struct super_block *sb) 675 { 676 struct btrfs_root *root = btrfs_sb(sb); 677 mutex_unlock(&root->fs_info->cleaner_mutex); 678 mutex_unlock(&root->fs_info->transaction_kthread_mutex); 679 return 0; 680 } 681 682 static struct super_operations btrfs_super_ops = { 683 .delete_inode = btrfs_delete_inode, 684 .put_super = btrfs_put_super, 685 .write_super = btrfs_write_super, 686 .sync_fs = btrfs_sync_fs, 687 .show_options = btrfs_show_options, 688 .write_inode = btrfs_write_inode, 689 .dirty_inode = btrfs_dirty_inode, 690 .alloc_inode = btrfs_alloc_inode, 691 .destroy_inode = btrfs_destroy_inode, 692 .statfs = btrfs_statfs, 693 .remount_fs = btrfs_remount, 694 .freeze_fs = btrfs_freeze, 695 .unfreeze_fs = btrfs_unfreeze, 696 }; 697 698 static const struct file_operations btrfs_ctl_fops = { 699 .unlocked_ioctl = btrfs_control_ioctl, 700 .compat_ioctl = btrfs_control_ioctl, 701 .owner = THIS_MODULE, 702 }; 703 704 static struct miscdevice btrfs_misc = { 705 .minor = MISC_DYNAMIC_MINOR, 706 .name = "btrfs-control", 707 .fops = &btrfs_ctl_fops 708 }; 709 710 static int btrfs_interface_init(void) 711 { 712 return misc_register(&btrfs_misc); 713 } 714 715 static void btrfs_interface_exit(void) 716 { 717 if (misc_deregister(&btrfs_misc) < 0) 718 printk(KERN_INFO "misc_deregister failed for control device"); 719 } 720 721 static int __init init_btrfs_fs(void) 722 { 723 int err; 724 725 err = btrfs_init_sysfs(); 726 if (err) 727 return err; 728 729 err = btrfs_init_cachep(); 730 if (err) 731 goto free_sysfs; 732 733 err = extent_io_init(); 734 if (err) 735 goto free_cachep; 736 737 err = extent_map_init(); 738 if (err) 739 goto free_extent_io; 740 741 err = btrfs_interface_init(); 742 if (err) 743 goto free_extent_map; 744 745 err = register_filesystem(&btrfs_fs_type); 746 if (err) 747 goto unregister_ioctl; 748 749 printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); 750 return 0; 751 752 unregister_ioctl: 753 btrfs_interface_exit(); 754 free_extent_map: 755 extent_map_exit(); 756 free_extent_io: 757 extent_io_exit(); 758 free_cachep: 759 btrfs_destroy_cachep(); 760 free_sysfs: 761 btrfs_exit_sysfs(); 762 return err; 763 } 764 765 static void __exit exit_btrfs_fs(void) 766 { 767 btrfs_destroy_cachep(); 768 extent_map_exit(); 769 extent_io_exit(); 770 btrfs_interface_exit(); 771 unregister_filesystem(&btrfs_fs_type); 772 btrfs_exit_sysfs(); 773 btrfs_cleanup_fs_uuids(); 774 btrfs_zlib_exit(); 775 } 776 777 module_init(init_btrfs_fs) 778 module_exit(exit_btrfs_fs) 779 780 MODULE_LICENSE("GPL"); 781