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/backing-dev.h> 30 #include <linux/mount.h> 31 #include <linux/mpage.h> 32 #include <linux/swap.h> 33 #include <linux/writeback.h> 34 #include <linux/statfs.h> 35 #include <linux/compat.h> 36 #include <linux/parser.h> 37 #include <linux/ctype.h> 38 #include <linux/namei.h> 39 #include <linux/miscdevice.h> 40 #include <linux/magic.h> 41 #include "compat.h" 42 #include "ctree.h" 43 #include "disk-io.h" 44 #include "transaction.h" 45 #include "btrfs_inode.h" 46 #include "ioctl.h" 47 #include "print-tree.h" 48 #include "xattr.h" 49 #include "volumes.h" 50 #include "version.h" 51 #include "export.h" 52 #include "compression.h" 53 54 static const struct super_operations btrfs_super_ops; 55 56 static void btrfs_put_super(struct super_block *sb) 57 { 58 struct btrfs_root *root = btrfs_sb(sb); 59 int ret; 60 61 ret = close_ctree(root); 62 sb->s_fs_info = NULL; 63 } 64 65 enum { 66 Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow, 67 Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, 68 Opt_ssd, Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, 69 Opt_compress, Opt_notreelog, Opt_ratio, Opt_flushoncommit, 70 Opt_discard, 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_discard, "discard"}, 93 {Opt_err, NULL}, 94 }; 95 96 u64 btrfs_parse_size(char *str) 97 { 98 u64 res; 99 int mult = 1; 100 char *end; 101 char last; 102 103 res = simple_strtoul(str, &end, 10); 104 105 last = end[0]; 106 if (isalpha(last)) { 107 last = tolower(last); 108 switch (last) { 109 case 'g': 110 mult *= 1024; 111 case 'm': 112 mult *= 1024; 113 case 'k': 114 mult *= 1024; 115 } 116 res = res * mult; 117 } 118 return res; 119 } 120 121 /* 122 * Regular mount options parser. Everything that is needed only when 123 * reading in a new superblock is parsed here. 124 */ 125 int btrfs_parse_options(struct btrfs_root *root, char *options) 126 { 127 struct btrfs_fs_info *info = root->fs_info; 128 substring_t args[MAX_OPT_ARGS]; 129 char *p, *num; 130 int intarg; 131 132 if (!options) 133 return 0; 134 135 /* 136 * strsep changes the string, duplicate it because parse_options 137 * gets called twice 138 */ 139 options = kstrdup(options, GFP_NOFS); 140 if (!options) 141 return -ENOMEM; 142 143 144 while ((p = strsep(&options, ",")) != NULL) { 145 int token; 146 if (!*p) 147 continue; 148 149 token = match_token(p, tokens, args); 150 switch (token) { 151 case Opt_degraded: 152 printk(KERN_INFO "btrfs: allowing degraded mounts\n"); 153 btrfs_set_opt(info->mount_opt, DEGRADED); 154 break; 155 case Opt_subvol: 156 case Opt_device: 157 /* 158 * These are parsed by btrfs_parse_early_options 159 * and can be happily ignored here. 160 */ 161 break; 162 case Opt_nodatasum: 163 printk(KERN_INFO "btrfs: setting nodatasum\n"); 164 btrfs_set_opt(info->mount_opt, NODATASUM); 165 break; 166 case Opt_nodatacow: 167 printk(KERN_INFO "btrfs: setting nodatacow\n"); 168 btrfs_set_opt(info->mount_opt, NODATACOW); 169 btrfs_set_opt(info->mount_opt, NODATASUM); 170 break; 171 case Opt_compress: 172 printk(KERN_INFO "btrfs: use compression\n"); 173 btrfs_set_opt(info->mount_opt, COMPRESS); 174 break; 175 case Opt_ssd: 176 printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); 177 btrfs_set_opt(info->mount_opt, SSD); 178 break; 179 case Opt_ssd_spread: 180 printk(KERN_INFO "btrfs: use spread ssd " 181 "allocation scheme\n"); 182 btrfs_set_opt(info->mount_opt, SSD); 183 btrfs_set_opt(info->mount_opt, SSD_SPREAD); 184 break; 185 case Opt_nossd: 186 printk(KERN_INFO "btrfs: not using ssd allocation " 187 "scheme\n"); 188 btrfs_set_opt(info->mount_opt, NOSSD); 189 btrfs_clear_opt(info->mount_opt, SSD); 190 btrfs_clear_opt(info->mount_opt, SSD_SPREAD); 191 break; 192 case Opt_nobarrier: 193 printk(KERN_INFO "btrfs: turning off barriers\n"); 194 btrfs_set_opt(info->mount_opt, NOBARRIER); 195 break; 196 case Opt_thread_pool: 197 intarg = 0; 198 match_int(&args[0], &intarg); 199 if (intarg) { 200 info->thread_pool_size = intarg; 201 printk(KERN_INFO "btrfs: thread pool %d\n", 202 info->thread_pool_size); 203 } 204 break; 205 case Opt_max_extent: 206 num = match_strdup(&args[0]); 207 if (num) { 208 info->max_extent = btrfs_parse_size(num); 209 kfree(num); 210 211 info->max_extent = max_t(u64, 212 info->max_extent, root->sectorsize); 213 printk(KERN_INFO "btrfs: max_extent at %llu\n", 214 (unsigned long long)info->max_extent); 215 } 216 break; 217 case Opt_max_inline: 218 num = match_strdup(&args[0]); 219 if (num) { 220 info->max_inline = btrfs_parse_size(num); 221 kfree(num); 222 223 if (info->max_inline) { 224 info->max_inline = max_t(u64, 225 info->max_inline, 226 root->sectorsize); 227 } 228 printk(KERN_INFO "btrfs: max_inline at %llu\n", 229 (unsigned long long)info->max_inline); 230 } 231 break; 232 case Opt_alloc_start: 233 num = match_strdup(&args[0]); 234 if (num) { 235 info->alloc_start = btrfs_parse_size(num); 236 kfree(num); 237 printk(KERN_INFO 238 "btrfs: allocations start at %llu\n", 239 (unsigned long long)info->alloc_start); 240 } 241 break; 242 case Opt_noacl: 243 root->fs_info->sb->s_flags &= ~MS_POSIXACL; 244 break; 245 case Opt_notreelog: 246 printk(KERN_INFO "btrfs: disabling tree log\n"); 247 btrfs_set_opt(info->mount_opt, NOTREELOG); 248 break; 249 case Opt_flushoncommit: 250 printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); 251 btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); 252 break; 253 case Opt_ratio: 254 intarg = 0; 255 match_int(&args[0], &intarg); 256 if (intarg) { 257 info->metadata_ratio = intarg; 258 printk(KERN_INFO "btrfs: metadata ratio %d\n", 259 info->metadata_ratio); 260 } 261 break; 262 case Opt_discard: 263 btrfs_set_opt(info->mount_opt, DISCARD); 264 break; 265 default: 266 break; 267 } 268 } 269 kfree(options); 270 return 0; 271 } 272 273 /* 274 * Parse mount options that are required early in the mount process. 275 * 276 * All other options will be parsed on much later in the mount process and 277 * only when we need to allocate a new super block. 278 */ 279 static int btrfs_parse_early_options(const char *options, fmode_t flags, 280 void *holder, char **subvol_name, 281 struct btrfs_fs_devices **fs_devices) 282 { 283 substring_t args[MAX_OPT_ARGS]; 284 char *opts, *p; 285 int error = 0; 286 287 if (!options) 288 goto out; 289 290 /* 291 * strsep changes the string, duplicate it because parse_options 292 * gets called twice 293 */ 294 opts = kstrdup(options, GFP_KERNEL); 295 if (!opts) 296 return -ENOMEM; 297 298 while ((p = strsep(&opts, ",")) != NULL) { 299 int token; 300 if (!*p) 301 continue; 302 303 token = match_token(p, tokens, args); 304 switch (token) { 305 case Opt_subvol: 306 *subvol_name = match_strdup(&args[0]); 307 break; 308 case Opt_device: 309 error = btrfs_scan_one_device(match_strdup(&args[0]), 310 flags, holder, fs_devices); 311 if (error) 312 goto out_free_opts; 313 break; 314 default: 315 break; 316 } 317 } 318 319 out_free_opts: 320 kfree(opts); 321 out: 322 /* 323 * If no subvolume name is specified we use the default one. Allocate 324 * a copy of the string "." here so that code later in the 325 * mount path doesn't care if it's the default volume or another one. 326 */ 327 if (!*subvol_name) { 328 *subvol_name = kstrdup(".", GFP_KERNEL); 329 if (!*subvol_name) 330 return -ENOMEM; 331 } 332 return error; 333 } 334 335 static int btrfs_fill_super(struct super_block *sb, 336 struct btrfs_fs_devices *fs_devices, 337 void *data, int silent) 338 { 339 struct inode *inode; 340 struct dentry *root_dentry; 341 struct btrfs_super_block *disk_super; 342 struct btrfs_root *tree_root; 343 struct btrfs_key key; 344 int err; 345 346 sb->s_maxbytes = MAX_LFS_FILESIZE; 347 sb->s_magic = BTRFS_SUPER_MAGIC; 348 sb->s_op = &btrfs_super_ops; 349 sb->s_export_op = &btrfs_export_ops; 350 sb->s_xattr = btrfs_xattr_handlers; 351 sb->s_time_gran = 1; 352 #ifdef CONFIG_BTRFS_FS_POSIX_ACL 353 sb->s_flags |= MS_POSIXACL; 354 #endif 355 356 tree_root = open_ctree(sb, fs_devices, (char *)data); 357 358 if (IS_ERR(tree_root)) { 359 printk("btrfs: open_ctree failed\n"); 360 return PTR_ERR(tree_root); 361 } 362 sb->s_fs_info = tree_root; 363 disk_super = &tree_root->fs_info->super_copy; 364 365 key.objectid = BTRFS_FIRST_FREE_OBJECTID; 366 key.type = BTRFS_INODE_ITEM_KEY; 367 key.offset = 0; 368 inode = btrfs_iget(sb, &key, tree_root->fs_info->fs_root); 369 if (IS_ERR(inode)) { 370 err = PTR_ERR(inode); 371 goto fail_close; 372 } 373 374 root_dentry = d_alloc_root(inode); 375 if (!root_dentry) { 376 iput(inode); 377 err = -ENOMEM; 378 goto fail_close; 379 } 380 #if 0 381 /* this does the super kobj at the same time */ 382 err = btrfs_sysfs_add_super(tree_root->fs_info); 383 if (err) 384 goto fail_close; 385 #endif 386 387 sb->s_root = root_dentry; 388 389 save_mount_options(sb, data); 390 return 0; 391 392 fail_close: 393 close_ctree(tree_root); 394 return err; 395 } 396 397 int btrfs_sync_fs(struct super_block *sb, int wait) 398 { 399 struct btrfs_trans_handle *trans; 400 struct btrfs_root *root = btrfs_sb(sb); 401 int ret; 402 403 if (!wait) { 404 filemap_flush(root->fs_info->btree_inode->i_mapping); 405 return 0; 406 } 407 408 btrfs_start_delalloc_inodes(root); 409 btrfs_wait_ordered_extents(root, 0); 410 411 trans = btrfs_start_transaction(root, 1); 412 ret = btrfs_commit_transaction(trans, root); 413 return ret; 414 } 415 416 static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) 417 { 418 struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); 419 struct btrfs_fs_info *info = root->fs_info; 420 421 if (btrfs_test_opt(root, DEGRADED)) 422 seq_puts(seq, ",degraded"); 423 if (btrfs_test_opt(root, NODATASUM)) 424 seq_puts(seq, ",nodatasum"); 425 if (btrfs_test_opt(root, NODATACOW)) 426 seq_puts(seq, ",nodatacow"); 427 if (btrfs_test_opt(root, NOBARRIER)) 428 seq_puts(seq, ",nobarrier"); 429 if (info->max_extent != (u64)-1) 430 seq_printf(seq, ",max_extent=%llu", 431 (unsigned long long)info->max_extent); 432 if (info->max_inline != 8192 * 1024) 433 seq_printf(seq, ",max_inline=%llu", 434 (unsigned long long)info->max_inline); 435 if (info->alloc_start != 0) 436 seq_printf(seq, ",alloc_start=%llu", 437 (unsigned long long)info->alloc_start); 438 if (info->thread_pool_size != min_t(unsigned long, 439 num_online_cpus() + 2, 8)) 440 seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); 441 if (btrfs_test_opt(root, COMPRESS)) 442 seq_puts(seq, ",compress"); 443 if (btrfs_test_opt(root, NOSSD)) 444 seq_puts(seq, ",nossd"); 445 if (btrfs_test_opt(root, SSD_SPREAD)) 446 seq_puts(seq, ",ssd_spread"); 447 else if (btrfs_test_opt(root, SSD)) 448 seq_puts(seq, ",ssd"); 449 if (btrfs_test_opt(root, NOTREELOG)) 450 seq_puts(seq, ",notreelog"); 451 if (btrfs_test_opt(root, FLUSHONCOMMIT)) 452 seq_puts(seq, ",flushoncommit"); 453 if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) 454 seq_puts(seq, ",noacl"); 455 return 0; 456 } 457 458 static int btrfs_test_super(struct super_block *s, void *data) 459 { 460 struct btrfs_fs_devices *test_fs_devices = data; 461 struct btrfs_root *root = btrfs_sb(s); 462 463 return root->fs_info->fs_devices == test_fs_devices; 464 } 465 466 /* 467 * Find a superblock for the given device / mount point. 468 * 469 * Note: This is based on get_sb_bdev from fs/super.c with a few additions 470 * for multiple device setup. Make sure to keep it in sync. 471 */ 472 static int btrfs_get_sb(struct file_system_type *fs_type, int flags, 473 const char *dev_name, void *data, struct vfsmount *mnt) 474 { 475 char *subvol_name = NULL; 476 struct block_device *bdev = NULL; 477 struct super_block *s; 478 struct dentry *root; 479 struct btrfs_fs_devices *fs_devices = NULL; 480 fmode_t mode = FMODE_READ; 481 int error = 0; 482 483 if (!(flags & MS_RDONLY)) 484 mode |= FMODE_WRITE; 485 486 error = btrfs_parse_early_options(data, mode, fs_type, 487 &subvol_name, &fs_devices); 488 if (error) 489 return error; 490 491 error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); 492 if (error) 493 goto error_free_subvol_name; 494 495 error = btrfs_open_devices(fs_devices, mode, fs_type); 496 if (error) 497 goto error_free_subvol_name; 498 499 if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { 500 error = -EACCES; 501 goto error_close_devices; 502 } 503 504 bdev = fs_devices->latest_bdev; 505 s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); 506 if (IS_ERR(s)) 507 goto error_s; 508 509 if (s->s_root) { 510 if ((flags ^ s->s_flags) & MS_RDONLY) { 511 deactivate_locked_super(s); 512 error = -EBUSY; 513 goto error_close_devices; 514 } 515 516 btrfs_close_devices(fs_devices); 517 } else { 518 char b[BDEVNAME_SIZE]; 519 520 s->s_flags = flags; 521 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); 522 error = btrfs_fill_super(s, fs_devices, data, 523 flags & MS_SILENT ? 1 : 0); 524 if (error) { 525 deactivate_locked_super(s); 526 goto error_free_subvol_name; 527 } 528 529 btrfs_sb(s)->fs_info->bdev_holder = fs_type; 530 s->s_flags |= MS_ACTIVE; 531 } 532 533 if (!strcmp(subvol_name, ".")) 534 root = dget(s->s_root); 535 else { 536 mutex_lock(&s->s_root->d_inode->i_mutex); 537 root = lookup_one_len(subvol_name, s->s_root, 538 strlen(subvol_name)); 539 mutex_unlock(&s->s_root->d_inode->i_mutex); 540 541 if (IS_ERR(root)) { 542 deactivate_locked_super(s); 543 error = PTR_ERR(root); 544 goto error_free_subvol_name; 545 } 546 if (!root->d_inode) { 547 dput(root); 548 deactivate_locked_super(s); 549 error = -ENXIO; 550 goto error_free_subvol_name; 551 } 552 } 553 554 mnt->mnt_sb = s; 555 mnt->mnt_root = root; 556 557 kfree(subvol_name); 558 return 0; 559 560 error_s: 561 error = PTR_ERR(s); 562 error_close_devices: 563 btrfs_close_devices(fs_devices); 564 error_free_subvol_name: 565 kfree(subvol_name); 566 return error; 567 } 568 569 static int btrfs_remount(struct super_block *sb, int *flags, char *data) 570 { 571 struct btrfs_root *root = btrfs_sb(sb); 572 int ret; 573 574 ret = btrfs_parse_options(root, data); 575 if (ret) 576 return -EINVAL; 577 578 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 579 return 0; 580 581 if (*flags & MS_RDONLY) { 582 sb->s_flags |= MS_RDONLY; 583 584 ret = btrfs_commit_super(root); 585 WARN_ON(ret); 586 } else { 587 if (root->fs_info->fs_devices->rw_devices == 0) 588 return -EACCES; 589 590 if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) 591 return -EINVAL; 592 593 /* recover relocation */ 594 ret = btrfs_recover_relocation(root); 595 WARN_ON(ret); 596 597 ret = btrfs_cleanup_fs_roots(root->fs_info); 598 WARN_ON(ret); 599 600 sb->s_flags &= ~MS_RDONLY; 601 } 602 603 return 0; 604 } 605 606 static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) 607 { 608 struct btrfs_root *root = btrfs_sb(dentry->d_sb); 609 struct btrfs_super_block *disk_super = &root->fs_info->super_copy; 610 int bits = dentry->d_sb->s_blocksize_bits; 611 __be32 *fsid = (__be32 *)root->fs_info->fsid; 612 613 buf->f_namelen = BTRFS_NAME_LEN; 614 buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; 615 buf->f_bfree = buf->f_blocks - 616 (btrfs_super_bytes_used(disk_super) >> bits); 617 buf->f_bavail = buf->f_bfree; 618 buf->f_bsize = dentry->d_sb->s_blocksize; 619 buf->f_type = BTRFS_SUPER_MAGIC; 620 621 /* We treat it as constant endianness (it doesn't matter _which_) 622 because we want the fsid to come out the same whether mounted 623 on a big-endian or little-endian host */ 624 buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); 625 buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); 626 /* Mask in the root object ID too, to disambiguate subvols */ 627 buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; 628 buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; 629 630 return 0; 631 } 632 633 static struct file_system_type btrfs_fs_type = { 634 .owner = THIS_MODULE, 635 .name = "btrfs", 636 .get_sb = btrfs_get_sb, 637 .kill_sb = kill_anon_super, 638 .fs_flags = FS_REQUIRES_DEV, 639 }; 640 641 /* 642 * used by btrfsctl to scan devices when no FS is mounted 643 */ 644 static long btrfs_control_ioctl(struct file *file, unsigned int cmd, 645 unsigned long arg) 646 { 647 struct btrfs_ioctl_vol_args *vol; 648 struct btrfs_fs_devices *fs_devices; 649 int ret = -ENOTTY; 650 651 if (!capable(CAP_SYS_ADMIN)) 652 return -EPERM; 653 654 vol = memdup_user((void __user *)arg, sizeof(*vol)); 655 if (IS_ERR(vol)) 656 return PTR_ERR(vol); 657 658 switch (cmd) { 659 case BTRFS_IOC_SCAN_DEV: 660 ret = btrfs_scan_one_device(vol->name, FMODE_READ, 661 &btrfs_fs_type, &fs_devices); 662 break; 663 } 664 665 kfree(vol); 666 return ret; 667 } 668 669 static int btrfs_freeze(struct super_block *sb) 670 { 671 struct btrfs_root *root = btrfs_sb(sb); 672 mutex_lock(&root->fs_info->transaction_kthread_mutex); 673 mutex_lock(&root->fs_info->cleaner_mutex); 674 return 0; 675 } 676 677 static int btrfs_unfreeze(struct super_block *sb) 678 { 679 struct btrfs_root *root = btrfs_sb(sb); 680 mutex_unlock(&root->fs_info->cleaner_mutex); 681 mutex_unlock(&root->fs_info->transaction_kthread_mutex); 682 return 0; 683 } 684 685 static const struct super_operations btrfs_super_ops = { 686 .drop_inode = btrfs_drop_inode, 687 .delete_inode = btrfs_delete_inode, 688 .put_super = btrfs_put_super, 689 .sync_fs = btrfs_sync_fs, 690 .show_options = btrfs_show_options, 691 .write_inode = btrfs_write_inode, 692 .dirty_inode = btrfs_dirty_inode, 693 .alloc_inode = btrfs_alloc_inode, 694 .destroy_inode = btrfs_destroy_inode, 695 .statfs = btrfs_statfs, 696 .remount_fs = btrfs_remount, 697 .freeze_fs = btrfs_freeze, 698 .unfreeze_fs = btrfs_unfreeze, 699 }; 700 701 static const struct file_operations btrfs_ctl_fops = { 702 .unlocked_ioctl = btrfs_control_ioctl, 703 .compat_ioctl = btrfs_control_ioctl, 704 .owner = THIS_MODULE, 705 }; 706 707 static struct miscdevice btrfs_misc = { 708 .minor = MISC_DYNAMIC_MINOR, 709 .name = "btrfs-control", 710 .fops = &btrfs_ctl_fops 711 }; 712 713 static int btrfs_interface_init(void) 714 { 715 return misc_register(&btrfs_misc); 716 } 717 718 static void btrfs_interface_exit(void) 719 { 720 if (misc_deregister(&btrfs_misc) < 0) 721 printk(KERN_INFO "misc_deregister failed for control device"); 722 } 723 724 static int __init init_btrfs_fs(void) 725 { 726 int err; 727 728 err = btrfs_init_sysfs(); 729 if (err) 730 return err; 731 732 err = btrfs_init_cachep(); 733 if (err) 734 goto free_sysfs; 735 736 err = extent_io_init(); 737 if (err) 738 goto free_cachep; 739 740 err = extent_map_init(); 741 if (err) 742 goto free_extent_io; 743 744 err = btrfs_interface_init(); 745 if (err) 746 goto free_extent_map; 747 748 err = register_filesystem(&btrfs_fs_type); 749 if (err) 750 goto unregister_ioctl; 751 752 printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); 753 return 0; 754 755 unregister_ioctl: 756 btrfs_interface_exit(); 757 free_extent_map: 758 extent_map_exit(); 759 free_extent_io: 760 extent_io_exit(); 761 free_cachep: 762 btrfs_destroy_cachep(); 763 free_sysfs: 764 btrfs_exit_sysfs(); 765 return err; 766 } 767 768 static void __exit exit_btrfs_fs(void) 769 { 770 btrfs_destroy_cachep(); 771 extent_map_exit(); 772 extent_io_exit(); 773 btrfs_interface_exit(); 774 unregister_filesystem(&btrfs_fs_type); 775 btrfs_exit_sysfs(); 776 btrfs_cleanup_fs_uuids(); 777 btrfs_zlib_exit(); 778 } 779 780 module_init(init_btrfs_fs) 781 module_exit(exit_btrfs_fs) 782 783 MODULE_LICENSE("GPL"); 784