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