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