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/kernel.h> 20 #include <linux/bio.h> 21 #include <linux/buffer_head.h> 22 #include <linux/file.h> 23 #include <linux/fs.h> 24 #include <linux/fsnotify.h> 25 #include <linux/pagemap.h> 26 #include <linux/highmem.h> 27 #include <linux/time.h> 28 #include <linux/init.h> 29 #include <linux/string.h> 30 #include <linux/backing-dev.h> 31 #include <linux/mount.h> 32 #include <linux/mpage.h> 33 #include <linux/namei.h> 34 #include <linux/swap.h> 35 #include <linux/writeback.h> 36 #include <linux/statfs.h> 37 #include <linux/compat.h> 38 #include <linux/bit_spinlock.h> 39 #include <linux/security.h> 40 #include <linux/xattr.h> 41 #include <linux/vmalloc.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 "volumes.h" 50 #include "locking.h" 51 52 /* Mask out flags that are inappropriate for the given type of inode. */ 53 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags) 54 { 55 if (S_ISDIR(mode)) 56 return flags; 57 else if (S_ISREG(mode)) 58 return flags & ~FS_DIRSYNC_FL; 59 else 60 return flags & (FS_NODUMP_FL | FS_NOATIME_FL); 61 } 62 63 /* 64 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl. 65 */ 66 static unsigned int btrfs_flags_to_ioctl(unsigned int flags) 67 { 68 unsigned int iflags = 0; 69 70 if (flags & BTRFS_INODE_SYNC) 71 iflags |= FS_SYNC_FL; 72 if (flags & BTRFS_INODE_IMMUTABLE) 73 iflags |= FS_IMMUTABLE_FL; 74 if (flags & BTRFS_INODE_APPEND) 75 iflags |= FS_APPEND_FL; 76 if (flags & BTRFS_INODE_NODUMP) 77 iflags |= FS_NODUMP_FL; 78 if (flags & BTRFS_INODE_NOATIME) 79 iflags |= FS_NOATIME_FL; 80 if (flags & BTRFS_INODE_DIRSYNC) 81 iflags |= FS_DIRSYNC_FL; 82 83 return iflags; 84 } 85 86 /* 87 * Update inode->i_flags based on the btrfs internal flags. 88 */ 89 void btrfs_update_iflags(struct inode *inode) 90 { 91 struct btrfs_inode *ip = BTRFS_I(inode); 92 93 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); 94 95 if (ip->flags & BTRFS_INODE_SYNC) 96 inode->i_flags |= S_SYNC; 97 if (ip->flags & BTRFS_INODE_IMMUTABLE) 98 inode->i_flags |= S_IMMUTABLE; 99 if (ip->flags & BTRFS_INODE_APPEND) 100 inode->i_flags |= S_APPEND; 101 if (ip->flags & BTRFS_INODE_NOATIME) 102 inode->i_flags |= S_NOATIME; 103 if (ip->flags & BTRFS_INODE_DIRSYNC) 104 inode->i_flags |= S_DIRSYNC; 105 } 106 107 /* 108 * Inherit flags from the parent inode. 109 * 110 * Unlike extN we don't have any flags we don't want to inherit currently. 111 */ 112 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) 113 { 114 unsigned int flags; 115 116 if (!dir) 117 return; 118 119 flags = BTRFS_I(dir)->flags; 120 121 if (S_ISREG(inode->i_mode)) 122 flags &= ~BTRFS_INODE_DIRSYNC; 123 else if (!S_ISDIR(inode->i_mode)) 124 flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME); 125 126 BTRFS_I(inode)->flags = flags; 127 btrfs_update_iflags(inode); 128 } 129 130 static int btrfs_ioctl_getflags(struct file *file, void __user *arg) 131 { 132 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode); 133 unsigned int flags = btrfs_flags_to_ioctl(ip->flags); 134 135 if (copy_to_user(arg, &flags, sizeof(flags))) 136 return -EFAULT; 137 return 0; 138 } 139 140 static int btrfs_ioctl_setflags(struct file *file, void __user *arg) 141 { 142 struct inode *inode = file->f_path.dentry->d_inode; 143 struct btrfs_inode *ip = BTRFS_I(inode); 144 struct btrfs_root *root = ip->root; 145 struct btrfs_trans_handle *trans; 146 unsigned int flags, oldflags; 147 int ret; 148 149 if (copy_from_user(&flags, arg, sizeof(flags))) 150 return -EFAULT; 151 152 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ 153 FS_NOATIME_FL | FS_NODUMP_FL | \ 154 FS_SYNC_FL | FS_DIRSYNC_FL)) 155 return -EOPNOTSUPP; 156 157 if (!is_owner_or_cap(inode)) 158 return -EACCES; 159 160 mutex_lock(&inode->i_mutex); 161 162 flags = btrfs_mask_flags(inode->i_mode, flags); 163 oldflags = btrfs_flags_to_ioctl(ip->flags); 164 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { 165 if (!capable(CAP_LINUX_IMMUTABLE)) { 166 ret = -EPERM; 167 goto out_unlock; 168 } 169 } 170 171 ret = mnt_want_write(file->f_path.mnt); 172 if (ret) 173 goto out_unlock; 174 175 if (flags & FS_SYNC_FL) 176 ip->flags |= BTRFS_INODE_SYNC; 177 else 178 ip->flags &= ~BTRFS_INODE_SYNC; 179 if (flags & FS_IMMUTABLE_FL) 180 ip->flags |= BTRFS_INODE_IMMUTABLE; 181 else 182 ip->flags &= ~BTRFS_INODE_IMMUTABLE; 183 if (flags & FS_APPEND_FL) 184 ip->flags |= BTRFS_INODE_APPEND; 185 else 186 ip->flags &= ~BTRFS_INODE_APPEND; 187 if (flags & FS_NODUMP_FL) 188 ip->flags |= BTRFS_INODE_NODUMP; 189 else 190 ip->flags &= ~BTRFS_INODE_NODUMP; 191 if (flags & FS_NOATIME_FL) 192 ip->flags |= BTRFS_INODE_NOATIME; 193 else 194 ip->flags &= ~BTRFS_INODE_NOATIME; 195 if (flags & FS_DIRSYNC_FL) 196 ip->flags |= BTRFS_INODE_DIRSYNC; 197 else 198 ip->flags &= ~BTRFS_INODE_DIRSYNC; 199 200 201 trans = btrfs_join_transaction(root, 1); 202 BUG_ON(!trans); 203 204 ret = btrfs_update_inode(trans, root, inode); 205 BUG_ON(ret); 206 207 btrfs_update_iflags(inode); 208 inode->i_ctime = CURRENT_TIME; 209 btrfs_end_transaction(trans, root); 210 211 mnt_drop_write(file->f_path.mnt); 212 out_unlock: 213 mutex_unlock(&inode->i_mutex); 214 return 0; 215 } 216 217 static int btrfs_ioctl_getversion(struct file *file, int __user *arg) 218 { 219 struct inode *inode = file->f_path.dentry->d_inode; 220 221 return put_user(inode->i_generation, arg); 222 } 223 224 static noinline int create_subvol(struct btrfs_root *root, 225 struct dentry *dentry, 226 char *name, int namelen) 227 { 228 struct btrfs_trans_handle *trans; 229 struct btrfs_key key; 230 struct btrfs_root_item root_item; 231 struct btrfs_inode_item *inode_item; 232 struct extent_buffer *leaf; 233 struct btrfs_root *new_root = root; 234 struct inode *dir; 235 int ret; 236 int err; 237 u64 objectid; 238 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; 239 u64 index = 0; 240 unsigned long nr = 1; 241 242 ret = btrfs_check_metadata_free_space(root); 243 if (ret) 244 goto fail_commit; 245 246 trans = btrfs_start_transaction(root, 1); 247 BUG_ON(!trans); 248 249 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root, 250 0, &objectid); 251 if (ret) 252 goto fail; 253 254 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 255 0, objectid, NULL, 0, 0, 0); 256 if (IS_ERR(leaf)) { 257 ret = PTR_ERR(leaf); 258 goto fail; 259 } 260 261 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header)); 262 btrfs_set_header_bytenr(leaf, leaf->start); 263 btrfs_set_header_generation(leaf, trans->transid); 264 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV); 265 btrfs_set_header_owner(leaf, objectid); 266 267 write_extent_buffer(leaf, root->fs_info->fsid, 268 (unsigned long)btrfs_header_fsid(leaf), 269 BTRFS_FSID_SIZE); 270 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 271 (unsigned long)btrfs_header_chunk_tree_uuid(leaf), 272 BTRFS_UUID_SIZE); 273 btrfs_mark_buffer_dirty(leaf); 274 275 inode_item = &root_item.inode; 276 memset(inode_item, 0, sizeof(*inode_item)); 277 inode_item->generation = cpu_to_le64(1); 278 inode_item->size = cpu_to_le64(3); 279 inode_item->nlink = cpu_to_le32(1); 280 inode_item->nbytes = cpu_to_le64(root->leafsize); 281 inode_item->mode = cpu_to_le32(S_IFDIR | 0755); 282 283 btrfs_set_root_bytenr(&root_item, leaf->start); 284 btrfs_set_root_generation(&root_item, trans->transid); 285 btrfs_set_root_level(&root_item, 0); 286 btrfs_set_root_refs(&root_item, 1); 287 btrfs_set_root_used(&root_item, 0); 288 btrfs_set_root_last_snapshot(&root_item, 0); 289 290 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress)); 291 root_item.drop_level = 0; 292 293 btrfs_tree_unlock(leaf); 294 free_extent_buffer(leaf); 295 leaf = NULL; 296 297 btrfs_set_root_dirid(&root_item, new_dirid); 298 299 key.objectid = objectid; 300 key.offset = 0; 301 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); 302 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, 303 &root_item); 304 if (ret) 305 goto fail; 306 307 /* 308 * insert the directory item 309 */ 310 key.offset = (u64)-1; 311 dir = dentry->d_parent->d_inode; 312 ret = btrfs_set_inode_index(dir, &index); 313 BUG_ON(ret); 314 315 ret = btrfs_insert_dir_item(trans, root, 316 name, namelen, dir->i_ino, &key, 317 BTRFS_FT_DIR, index); 318 if (ret) 319 goto fail; 320 321 btrfs_i_size_write(dir, dir->i_size + namelen * 2); 322 ret = btrfs_update_inode(trans, root, dir); 323 BUG_ON(ret); 324 325 /* add the backref first */ 326 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, 327 objectid, BTRFS_ROOT_BACKREF_KEY, 328 root->root_key.objectid, 329 dir->i_ino, index, name, namelen); 330 331 BUG_ON(ret); 332 333 /* now add the forward ref */ 334 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, 335 root->root_key.objectid, BTRFS_ROOT_REF_KEY, 336 objectid, 337 dir->i_ino, index, name, namelen); 338 339 BUG_ON(ret); 340 341 ret = btrfs_commit_transaction(trans, root); 342 if (ret) 343 goto fail_commit; 344 345 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); 346 BUG_ON(!new_root); 347 348 trans = btrfs_start_transaction(new_root, 1); 349 BUG_ON(!trans); 350 351 ret = btrfs_create_subvol_root(trans, new_root, dentry, new_dirid, 352 BTRFS_I(dir)->block_group); 353 if (ret) 354 goto fail; 355 356 fail: 357 nr = trans->blocks_used; 358 err = btrfs_commit_transaction(trans, new_root); 359 if (err && !ret) 360 ret = err; 361 fail_commit: 362 btrfs_btree_balance_dirty(root, nr); 363 return ret; 364 } 365 366 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry, 367 char *name, int namelen) 368 { 369 struct btrfs_pending_snapshot *pending_snapshot; 370 struct btrfs_trans_handle *trans; 371 int ret = 0; 372 int err; 373 unsigned long nr = 0; 374 375 if (!root->ref_cows) 376 return -EINVAL; 377 378 ret = btrfs_check_metadata_free_space(root); 379 if (ret) 380 goto fail_unlock; 381 382 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); 383 if (!pending_snapshot) { 384 ret = -ENOMEM; 385 goto fail_unlock; 386 } 387 pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS); 388 if (!pending_snapshot->name) { 389 ret = -ENOMEM; 390 kfree(pending_snapshot); 391 goto fail_unlock; 392 } 393 memcpy(pending_snapshot->name, name, namelen); 394 pending_snapshot->name[namelen] = '\0'; 395 pending_snapshot->dentry = dentry; 396 trans = btrfs_start_transaction(root, 1); 397 BUG_ON(!trans); 398 pending_snapshot->root = root; 399 list_add(&pending_snapshot->list, 400 &trans->transaction->pending_snapshots); 401 err = btrfs_commit_transaction(trans, root); 402 403 fail_unlock: 404 btrfs_btree_balance_dirty(root, nr); 405 return ret; 406 } 407 408 /* copy of may_create in fs/namei.c() */ 409 static inline int btrfs_may_create(struct inode *dir, struct dentry *child) 410 { 411 if (child->d_inode) 412 return -EEXIST; 413 if (IS_DEADDIR(dir)) 414 return -ENOENT; 415 return inode_permission(dir, MAY_WRITE | MAY_EXEC); 416 } 417 418 /* 419 * Create a new subvolume below @parent. This is largely modeled after 420 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup 421 * inside this filesystem so it's quite a bit simpler. 422 */ 423 static noinline int btrfs_mksubvol(struct path *parent, char *name, 424 int mode, int namelen, 425 struct btrfs_root *snap_src) 426 { 427 struct dentry *dentry; 428 int error; 429 430 mutex_lock_nested(&parent->dentry->d_inode->i_mutex, I_MUTEX_PARENT); 431 432 dentry = lookup_one_len(name, parent->dentry, namelen); 433 error = PTR_ERR(dentry); 434 if (IS_ERR(dentry)) 435 goto out_unlock; 436 437 error = -EEXIST; 438 if (dentry->d_inode) 439 goto out_dput; 440 441 if (!IS_POSIXACL(parent->dentry->d_inode)) 442 mode &= ~current_umask(); 443 444 error = mnt_want_write(parent->mnt); 445 if (error) 446 goto out_dput; 447 448 error = btrfs_may_create(parent->dentry->d_inode, dentry); 449 if (error) 450 goto out_drop_write; 451 452 /* 453 * Actually perform the low-level subvolume creation after all 454 * this VFS fuzz. 455 * 456 * Eventually we want to pass in an inode under which we create this 457 * subvolume, but for now all are under the filesystem root. 458 * 459 * Also we should pass on the mode eventually to allow creating new 460 * subvolume with specific mode bits. 461 */ 462 if (snap_src) { 463 struct dentry *dir = dentry->d_parent; 464 struct dentry *test = dir->d_parent; 465 struct btrfs_path *path = btrfs_alloc_path(); 466 int ret; 467 u64 test_oid; 468 u64 parent_oid = BTRFS_I(dir->d_inode)->root->root_key.objectid; 469 470 test_oid = snap_src->root_key.objectid; 471 472 ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, 473 path, parent_oid, test_oid); 474 if (ret == 0) 475 goto create; 476 btrfs_release_path(snap_src->fs_info->tree_root, path); 477 478 /* we need to make sure we aren't creating a directory loop 479 * by taking a snapshot of something that has our current 480 * subvol in its directory tree. So, this loops through 481 * the dentries and checks the forward refs for each subvolume 482 * to see if is references the subvolume where we are 483 * placing this new snapshot. 484 */ 485 while (1) { 486 if (!test || 487 dir == snap_src->fs_info->sb->s_root || 488 test == snap_src->fs_info->sb->s_root || 489 test->d_inode->i_sb != snap_src->fs_info->sb) { 490 break; 491 } 492 if (S_ISLNK(test->d_inode->i_mode)) { 493 printk(KERN_INFO "Btrfs symlink in snapshot " 494 "path, failed\n"); 495 error = -EMLINK; 496 btrfs_free_path(path); 497 goto out_drop_write; 498 } 499 test_oid = 500 BTRFS_I(test->d_inode)->root->root_key.objectid; 501 ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, 502 path, test_oid, parent_oid); 503 if (ret == 0) { 504 printk(KERN_INFO "Btrfs snapshot creation " 505 "failed, looping\n"); 506 error = -EMLINK; 507 btrfs_free_path(path); 508 goto out_drop_write; 509 } 510 btrfs_release_path(snap_src->fs_info->tree_root, path); 511 test = test->d_parent; 512 } 513 create: 514 btrfs_free_path(path); 515 error = create_snapshot(snap_src, dentry, name, namelen); 516 } else { 517 error = create_subvol(BTRFS_I(parent->dentry->d_inode)->root, 518 dentry, name, namelen); 519 } 520 if (error) 521 goto out_drop_write; 522 523 fsnotify_mkdir(parent->dentry->d_inode, dentry); 524 out_drop_write: 525 mnt_drop_write(parent->mnt); 526 out_dput: 527 dput(dentry); 528 out_unlock: 529 mutex_unlock(&parent->dentry->d_inode->i_mutex); 530 return error; 531 } 532 533 534 static int btrfs_defrag_file(struct file *file) 535 { 536 struct inode *inode = fdentry(file)->d_inode; 537 struct btrfs_root *root = BTRFS_I(inode)->root; 538 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 539 struct btrfs_ordered_extent *ordered; 540 struct page *page; 541 unsigned long last_index; 542 unsigned long ra_pages = root->fs_info->bdi.ra_pages; 543 unsigned long total_read = 0; 544 u64 page_start; 545 u64 page_end; 546 unsigned long i; 547 int ret; 548 549 ret = btrfs_check_data_free_space(root, inode, inode->i_size); 550 if (ret) 551 return -ENOSPC; 552 553 mutex_lock(&inode->i_mutex); 554 last_index = inode->i_size >> PAGE_CACHE_SHIFT; 555 for (i = 0; i <= last_index; i++) { 556 if (total_read % ra_pages == 0) { 557 btrfs_force_ra(inode->i_mapping, &file->f_ra, file, i, 558 min(last_index, i + ra_pages - 1)); 559 } 560 total_read++; 561 again: 562 page = grab_cache_page(inode->i_mapping, i); 563 if (!page) 564 goto out_unlock; 565 if (!PageUptodate(page)) { 566 btrfs_readpage(NULL, page); 567 lock_page(page); 568 if (!PageUptodate(page)) { 569 unlock_page(page); 570 page_cache_release(page); 571 goto out_unlock; 572 } 573 } 574 575 wait_on_page_writeback(page); 576 577 page_start = (u64)page->index << PAGE_CACHE_SHIFT; 578 page_end = page_start + PAGE_CACHE_SIZE - 1; 579 lock_extent(io_tree, page_start, page_end, GFP_NOFS); 580 581 ordered = btrfs_lookup_ordered_extent(inode, page_start); 582 if (ordered) { 583 unlock_extent(io_tree, page_start, page_end, GFP_NOFS); 584 unlock_page(page); 585 page_cache_release(page); 586 btrfs_start_ordered_extent(inode, ordered, 1); 587 btrfs_put_ordered_extent(ordered); 588 goto again; 589 } 590 set_page_extent_mapped(page); 591 592 /* 593 * this makes sure page_mkwrite is called on the 594 * page if it is dirtied again later 595 */ 596 clear_page_dirty_for_io(page); 597 598 btrfs_set_extent_delalloc(inode, page_start, page_end); 599 600 unlock_extent(io_tree, page_start, page_end, GFP_NOFS); 601 set_page_dirty(page); 602 unlock_page(page); 603 page_cache_release(page); 604 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1); 605 } 606 607 out_unlock: 608 mutex_unlock(&inode->i_mutex); 609 return 0; 610 } 611 612 static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg) 613 { 614 u64 new_size; 615 u64 old_size; 616 u64 devid = 1; 617 struct btrfs_ioctl_vol_args *vol_args; 618 struct btrfs_trans_handle *trans; 619 struct btrfs_device *device = NULL; 620 char *sizestr; 621 char *devstr = NULL; 622 int ret = 0; 623 int namelen; 624 int mod = 0; 625 626 if (root->fs_info->sb->s_flags & MS_RDONLY) 627 return -EROFS; 628 629 if (!capable(CAP_SYS_ADMIN)) 630 return -EPERM; 631 632 vol_args = memdup_user(arg, sizeof(*vol_args)); 633 if (IS_ERR(vol_args)) 634 return PTR_ERR(vol_args); 635 636 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 637 namelen = strlen(vol_args->name); 638 639 mutex_lock(&root->fs_info->volume_mutex); 640 sizestr = vol_args->name; 641 devstr = strchr(sizestr, ':'); 642 if (devstr) { 643 char *end; 644 sizestr = devstr + 1; 645 *devstr = '\0'; 646 devstr = vol_args->name; 647 devid = simple_strtoull(devstr, &end, 10); 648 printk(KERN_INFO "resizing devid %llu\n", 649 (unsigned long long)devid); 650 } 651 device = btrfs_find_device(root, devid, NULL, NULL); 652 if (!device) { 653 printk(KERN_INFO "resizer unable to find device %llu\n", 654 (unsigned long long)devid); 655 ret = -EINVAL; 656 goto out_unlock; 657 } 658 if (!strcmp(sizestr, "max")) 659 new_size = device->bdev->bd_inode->i_size; 660 else { 661 if (sizestr[0] == '-') { 662 mod = -1; 663 sizestr++; 664 } else if (sizestr[0] == '+') { 665 mod = 1; 666 sizestr++; 667 } 668 new_size = btrfs_parse_size(sizestr); 669 if (new_size == 0) { 670 ret = -EINVAL; 671 goto out_unlock; 672 } 673 } 674 675 old_size = device->total_bytes; 676 677 if (mod < 0) { 678 if (new_size > old_size) { 679 ret = -EINVAL; 680 goto out_unlock; 681 } 682 new_size = old_size - new_size; 683 } else if (mod > 0) { 684 new_size = old_size + new_size; 685 } 686 687 if (new_size < 256 * 1024 * 1024) { 688 ret = -EINVAL; 689 goto out_unlock; 690 } 691 if (new_size > device->bdev->bd_inode->i_size) { 692 ret = -EFBIG; 693 goto out_unlock; 694 } 695 696 do_div(new_size, root->sectorsize); 697 new_size *= root->sectorsize; 698 699 printk(KERN_INFO "new size for %s is %llu\n", 700 device->name, (unsigned long long)new_size); 701 702 if (new_size > old_size) { 703 trans = btrfs_start_transaction(root, 1); 704 ret = btrfs_grow_device(trans, device, new_size); 705 btrfs_commit_transaction(trans, root); 706 } else { 707 ret = btrfs_shrink_device(device, new_size); 708 } 709 710 out_unlock: 711 mutex_unlock(&root->fs_info->volume_mutex); 712 kfree(vol_args); 713 return ret; 714 } 715 716 static noinline int btrfs_ioctl_snap_create(struct file *file, 717 void __user *arg, int subvol) 718 { 719 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 720 struct btrfs_ioctl_vol_args *vol_args; 721 struct btrfs_dir_item *di; 722 struct btrfs_path *path; 723 struct file *src_file; 724 u64 root_dirid; 725 int namelen; 726 int ret = 0; 727 728 if (root->fs_info->sb->s_flags & MS_RDONLY) 729 return -EROFS; 730 731 vol_args = memdup_user(arg, sizeof(*vol_args)); 732 if (IS_ERR(vol_args)) 733 return PTR_ERR(vol_args); 734 735 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 736 namelen = strlen(vol_args->name); 737 if (strchr(vol_args->name, '/')) { 738 ret = -EINVAL; 739 goto out; 740 } 741 742 path = btrfs_alloc_path(); 743 if (!path) { 744 ret = -ENOMEM; 745 goto out; 746 } 747 748 root_dirid = root->fs_info->sb->s_root->d_inode->i_ino, 749 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, 750 path, root_dirid, 751 vol_args->name, namelen, 0); 752 btrfs_free_path(path); 753 754 if (di && !IS_ERR(di)) { 755 ret = -EEXIST; 756 goto out; 757 } 758 759 if (IS_ERR(di)) { 760 ret = PTR_ERR(di); 761 goto out; 762 } 763 764 if (subvol) { 765 ret = btrfs_mksubvol(&file->f_path, vol_args->name, 766 file->f_path.dentry->d_inode->i_mode, 767 namelen, NULL); 768 } else { 769 struct inode *src_inode; 770 src_file = fget(vol_args->fd); 771 if (!src_file) { 772 ret = -EINVAL; 773 goto out; 774 } 775 776 src_inode = src_file->f_path.dentry->d_inode; 777 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { 778 printk(KERN_INFO "btrfs: Snapshot src from " 779 "another FS\n"); 780 ret = -EINVAL; 781 fput(src_file); 782 goto out; 783 } 784 ret = btrfs_mksubvol(&file->f_path, vol_args->name, 785 file->f_path.dentry->d_inode->i_mode, 786 namelen, BTRFS_I(src_inode)->root); 787 fput(src_file); 788 } 789 790 out: 791 kfree(vol_args); 792 return ret; 793 } 794 795 static int btrfs_ioctl_defrag(struct file *file) 796 { 797 struct inode *inode = fdentry(file)->d_inode; 798 struct btrfs_root *root = BTRFS_I(inode)->root; 799 int ret; 800 801 ret = mnt_want_write(file->f_path.mnt); 802 if (ret) 803 return ret; 804 805 switch (inode->i_mode & S_IFMT) { 806 case S_IFDIR: 807 if (!capable(CAP_SYS_ADMIN)) { 808 ret = -EPERM; 809 goto out; 810 } 811 btrfs_defrag_root(root, 0); 812 btrfs_defrag_root(root->fs_info->extent_root, 0); 813 break; 814 case S_IFREG: 815 if (!(file->f_mode & FMODE_WRITE)) { 816 ret = -EINVAL; 817 goto out; 818 } 819 btrfs_defrag_file(file); 820 break; 821 } 822 out: 823 mnt_drop_write(file->f_path.mnt); 824 return ret; 825 } 826 827 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 828 { 829 struct btrfs_ioctl_vol_args *vol_args; 830 int ret; 831 832 if (!capable(CAP_SYS_ADMIN)) 833 return -EPERM; 834 835 vol_args = memdup_user(arg, sizeof(*vol_args)); 836 if (IS_ERR(vol_args)) 837 return PTR_ERR(vol_args); 838 839 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 840 ret = btrfs_init_new_device(root, vol_args->name); 841 842 kfree(vol_args); 843 return ret; 844 } 845 846 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) 847 { 848 struct btrfs_ioctl_vol_args *vol_args; 849 int ret; 850 851 if (!capable(CAP_SYS_ADMIN)) 852 return -EPERM; 853 854 if (root->fs_info->sb->s_flags & MS_RDONLY) 855 return -EROFS; 856 857 vol_args = memdup_user(arg, sizeof(*vol_args)); 858 if (IS_ERR(vol_args)) 859 return PTR_ERR(vol_args); 860 861 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 862 ret = btrfs_rm_device(root, vol_args->name); 863 864 kfree(vol_args); 865 return ret; 866 } 867 868 static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 869 u64 off, u64 olen, u64 destoff) 870 { 871 struct inode *inode = fdentry(file)->d_inode; 872 struct btrfs_root *root = BTRFS_I(inode)->root; 873 struct file *src_file; 874 struct inode *src; 875 struct btrfs_trans_handle *trans; 876 struct btrfs_path *path; 877 struct extent_buffer *leaf; 878 char *buf; 879 struct btrfs_key key; 880 u32 nritems; 881 int slot; 882 int ret; 883 u64 len = olen; 884 u64 bs = root->fs_info->sb->s_blocksize; 885 u64 hint_byte; 886 887 /* 888 * TODO: 889 * - split compressed inline extents. annoying: we need to 890 * decompress into destination's address_space (the file offset 891 * may change, so source mapping won't do), then recompress (or 892 * otherwise reinsert) a subrange. 893 * - allow ranges within the same file to be cloned (provided 894 * they don't overlap)? 895 */ 896 897 /* the destination must be opened for writing */ 898 if (!(file->f_mode & FMODE_WRITE)) 899 return -EINVAL; 900 901 ret = mnt_want_write(file->f_path.mnt); 902 if (ret) 903 return ret; 904 905 src_file = fget(srcfd); 906 if (!src_file) { 907 ret = -EBADF; 908 goto out_drop_write; 909 } 910 src = src_file->f_dentry->d_inode; 911 912 ret = -EINVAL; 913 if (src == inode) 914 goto out_fput; 915 916 ret = -EISDIR; 917 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 918 goto out_fput; 919 920 ret = -EXDEV; 921 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root) 922 goto out_fput; 923 924 ret = -ENOMEM; 925 buf = vmalloc(btrfs_level_size(root, 0)); 926 if (!buf) 927 goto out_fput; 928 929 path = btrfs_alloc_path(); 930 if (!path) { 931 vfree(buf); 932 goto out_fput; 933 } 934 path->reada = 2; 935 936 if (inode < src) { 937 mutex_lock(&inode->i_mutex); 938 mutex_lock(&src->i_mutex); 939 } else { 940 mutex_lock(&src->i_mutex); 941 mutex_lock(&inode->i_mutex); 942 } 943 944 /* determine range to clone */ 945 ret = -EINVAL; 946 if (off >= src->i_size || off + len > src->i_size) 947 goto out_unlock; 948 if (len == 0) 949 olen = len = src->i_size - off; 950 /* if we extend to eof, continue to block boundary */ 951 if (off + len == src->i_size) 952 len = ((src->i_size + bs-1) & ~(bs-1)) 953 - off; 954 955 /* verify the end result is block aligned */ 956 if ((off & (bs-1)) || 957 ((off + len) & (bs-1))) 958 goto out_unlock; 959 960 /* do any pending delalloc/csum calc on src, one way or 961 another, and lock file content */ 962 while (1) { 963 struct btrfs_ordered_extent *ordered; 964 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 965 ordered = btrfs_lookup_first_ordered_extent(inode, off+len); 966 if (BTRFS_I(src)->delalloc_bytes == 0 && !ordered) 967 break; 968 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 969 if (ordered) 970 btrfs_put_ordered_extent(ordered); 971 btrfs_wait_ordered_range(src, off, off+len); 972 } 973 974 trans = btrfs_start_transaction(root, 1); 975 BUG_ON(!trans); 976 977 /* punch hole in destination first */ 978 btrfs_drop_extents(trans, root, inode, off, off + len, 979 off + len, 0, &hint_byte); 980 981 /* clone data */ 982 key.objectid = src->i_ino; 983 key.type = BTRFS_EXTENT_DATA_KEY; 984 key.offset = 0; 985 986 while (1) { 987 /* 988 * note the key will change type as we walk through the 989 * tree. 990 */ 991 ret = btrfs_search_slot(trans, root, &key, path, 0, 0); 992 if (ret < 0) 993 goto out; 994 995 nritems = btrfs_header_nritems(path->nodes[0]); 996 if (path->slots[0] >= nritems) { 997 ret = btrfs_next_leaf(root, path); 998 if (ret < 0) 999 goto out; 1000 if (ret > 0) 1001 break; 1002 nritems = btrfs_header_nritems(path->nodes[0]); 1003 } 1004 leaf = path->nodes[0]; 1005 slot = path->slots[0]; 1006 1007 btrfs_item_key_to_cpu(leaf, &key, slot); 1008 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || 1009 key.objectid != src->i_ino) 1010 break; 1011 1012 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { 1013 struct btrfs_file_extent_item *extent; 1014 int type; 1015 u32 size; 1016 struct btrfs_key new_key; 1017 u64 disko = 0, diskl = 0; 1018 u64 datao = 0, datal = 0; 1019 u8 comp; 1020 1021 size = btrfs_item_size_nr(leaf, slot); 1022 read_extent_buffer(leaf, buf, 1023 btrfs_item_ptr_offset(leaf, slot), 1024 size); 1025 1026 extent = btrfs_item_ptr(leaf, slot, 1027 struct btrfs_file_extent_item); 1028 comp = btrfs_file_extent_compression(leaf, extent); 1029 type = btrfs_file_extent_type(leaf, extent); 1030 if (type == BTRFS_FILE_EXTENT_REG || 1031 type == BTRFS_FILE_EXTENT_PREALLOC) { 1032 disko = btrfs_file_extent_disk_bytenr(leaf, 1033 extent); 1034 diskl = btrfs_file_extent_disk_num_bytes(leaf, 1035 extent); 1036 datao = btrfs_file_extent_offset(leaf, extent); 1037 datal = btrfs_file_extent_num_bytes(leaf, 1038 extent); 1039 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 1040 /* take upper bound, may be compressed */ 1041 datal = btrfs_file_extent_ram_bytes(leaf, 1042 extent); 1043 } 1044 btrfs_release_path(root, path); 1045 1046 if (key.offset + datal < off || 1047 key.offset >= off+len) 1048 goto next; 1049 1050 memcpy(&new_key, &key, sizeof(new_key)); 1051 new_key.objectid = inode->i_ino; 1052 new_key.offset = key.offset + destoff - off; 1053 1054 if (type == BTRFS_FILE_EXTENT_REG || 1055 type == BTRFS_FILE_EXTENT_PREALLOC) { 1056 ret = btrfs_insert_empty_item(trans, root, path, 1057 &new_key, size); 1058 if (ret) 1059 goto out; 1060 1061 leaf = path->nodes[0]; 1062 slot = path->slots[0]; 1063 write_extent_buffer(leaf, buf, 1064 btrfs_item_ptr_offset(leaf, slot), 1065 size); 1066 1067 extent = btrfs_item_ptr(leaf, slot, 1068 struct btrfs_file_extent_item); 1069 1070 if (off > key.offset) { 1071 datao += off - key.offset; 1072 datal -= off - key.offset; 1073 } 1074 if (key.offset + datao + datal + key.offset > 1075 off + len) 1076 datal = off + len - key.offset - datao; 1077 /* disko == 0 means it's a hole */ 1078 if (!disko) 1079 datao = 0; 1080 1081 btrfs_set_file_extent_offset(leaf, extent, 1082 datao); 1083 btrfs_set_file_extent_num_bytes(leaf, extent, 1084 datal); 1085 if (disko) { 1086 inode_add_bytes(inode, datal); 1087 ret = btrfs_inc_extent_ref(trans, root, 1088 disko, diskl, 0, 1089 root->root_key.objectid, 1090 inode->i_ino, 1091 new_key.offset - datao); 1092 BUG_ON(ret); 1093 } 1094 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 1095 u64 skip = 0; 1096 u64 trim = 0; 1097 if (off > key.offset) { 1098 skip = off - key.offset; 1099 new_key.offset += skip; 1100 } 1101 1102 if (key.offset + datal > off+len) 1103 trim = key.offset + datal - (off+len); 1104 1105 if (comp && (skip || trim)) { 1106 ret = -EINVAL; 1107 goto out; 1108 } 1109 size -= skip + trim; 1110 datal -= skip + trim; 1111 ret = btrfs_insert_empty_item(trans, root, path, 1112 &new_key, size); 1113 if (ret) 1114 goto out; 1115 1116 if (skip) { 1117 u32 start = 1118 btrfs_file_extent_calc_inline_size(0); 1119 memmove(buf+start, buf+start+skip, 1120 datal); 1121 } 1122 1123 leaf = path->nodes[0]; 1124 slot = path->slots[0]; 1125 write_extent_buffer(leaf, buf, 1126 btrfs_item_ptr_offset(leaf, slot), 1127 size); 1128 inode_add_bytes(inode, datal); 1129 } 1130 1131 btrfs_mark_buffer_dirty(leaf); 1132 } 1133 1134 next: 1135 btrfs_release_path(root, path); 1136 key.offset++; 1137 } 1138 ret = 0; 1139 out: 1140 btrfs_release_path(root, path); 1141 if (ret == 0) { 1142 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1143 if (destoff + olen > inode->i_size) 1144 btrfs_i_size_write(inode, destoff + olen); 1145 BTRFS_I(inode)->flags = BTRFS_I(src)->flags; 1146 ret = btrfs_update_inode(trans, root, inode); 1147 } 1148 btrfs_end_transaction(trans, root); 1149 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 1150 if (ret) 1151 vmtruncate(inode, 0); 1152 out_unlock: 1153 mutex_unlock(&src->i_mutex); 1154 mutex_unlock(&inode->i_mutex); 1155 vfree(buf); 1156 btrfs_free_path(path); 1157 out_fput: 1158 fput(src_file); 1159 out_drop_write: 1160 mnt_drop_write(file->f_path.mnt); 1161 return ret; 1162 } 1163 1164 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) 1165 { 1166 struct btrfs_ioctl_clone_range_args args; 1167 1168 if (copy_from_user(&args, argp, sizeof(args))) 1169 return -EFAULT; 1170 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, 1171 args.src_length, args.dest_offset); 1172 } 1173 1174 /* 1175 * there are many ways the trans_start and trans_end ioctls can lead 1176 * to deadlocks. They should only be used by applications that 1177 * basically own the machine, and have a very in depth understanding 1178 * of all the possible deadlocks and enospc problems. 1179 */ 1180 static long btrfs_ioctl_trans_start(struct file *file) 1181 { 1182 struct inode *inode = fdentry(file)->d_inode; 1183 struct btrfs_root *root = BTRFS_I(inode)->root; 1184 struct btrfs_trans_handle *trans; 1185 int ret = 0; 1186 1187 if (!capable(CAP_SYS_ADMIN)) 1188 return -EPERM; 1189 1190 if (file->private_data) { 1191 ret = -EINPROGRESS; 1192 goto out; 1193 } 1194 1195 ret = mnt_want_write(file->f_path.mnt); 1196 if (ret) 1197 goto out; 1198 1199 mutex_lock(&root->fs_info->trans_mutex); 1200 root->fs_info->open_ioctl_trans++; 1201 mutex_unlock(&root->fs_info->trans_mutex); 1202 1203 trans = btrfs_start_ioctl_transaction(root, 0); 1204 if (trans) 1205 file->private_data = trans; 1206 else 1207 ret = -ENOMEM; 1208 /*printk(KERN_INFO "btrfs_ioctl_trans_start on %p\n", file);*/ 1209 out: 1210 return ret; 1211 } 1212 1213 /* 1214 * there are many ways the trans_start and trans_end ioctls can lead 1215 * to deadlocks. They should only be used by applications that 1216 * basically own the machine, and have a very in depth understanding 1217 * of all the possible deadlocks and enospc problems. 1218 */ 1219 long btrfs_ioctl_trans_end(struct file *file) 1220 { 1221 struct inode *inode = fdentry(file)->d_inode; 1222 struct btrfs_root *root = BTRFS_I(inode)->root; 1223 struct btrfs_trans_handle *trans; 1224 int ret = 0; 1225 1226 trans = file->private_data; 1227 if (!trans) { 1228 ret = -EINVAL; 1229 goto out; 1230 } 1231 btrfs_end_transaction(trans, root); 1232 file->private_data = NULL; 1233 1234 mutex_lock(&root->fs_info->trans_mutex); 1235 root->fs_info->open_ioctl_trans--; 1236 mutex_unlock(&root->fs_info->trans_mutex); 1237 1238 mnt_drop_write(file->f_path.mnt); 1239 1240 out: 1241 return ret; 1242 } 1243 1244 long btrfs_ioctl(struct file *file, unsigned int 1245 cmd, unsigned long arg) 1246 { 1247 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 1248 void __user *argp = (void __user *)arg; 1249 1250 switch (cmd) { 1251 case FS_IOC_GETFLAGS: 1252 return btrfs_ioctl_getflags(file, argp); 1253 case FS_IOC_SETFLAGS: 1254 return btrfs_ioctl_setflags(file, argp); 1255 case FS_IOC_GETVERSION: 1256 return btrfs_ioctl_getversion(file, argp); 1257 case BTRFS_IOC_SNAP_CREATE: 1258 return btrfs_ioctl_snap_create(file, argp, 0); 1259 case BTRFS_IOC_SUBVOL_CREATE: 1260 return btrfs_ioctl_snap_create(file, argp, 1); 1261 case BTRFS_IOC_DEFRAG: 1262 return btrfs_ioctl_defrag(file); 1263 case BTRFS_IOC_RESIZE: 1264 return btrfs_ioctl_resize(root, argp); 1265 case BTRFS_IOC_ADD_DEV: 1266 return btrfs_ioctl_add_dev(root, argp); 1267 case BTRFS_IOC_RM_DEV: 1268 return btrfs_ioctl_rm_dev(root, argp); 1269 case BTRFS_IOC_BALANCE: 1270 return btrfs_balance(root->fs_info->dev_root); 1271 case BTRFS_IOC_CLONE: 1272 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 1273 case BTRFS_IOC_CLONE_RANGE: 1274 return btrfs_ioctl_clone_range(file, argp); 1275 case BTRFS_IOC_TRANS_START: 1276 return btrfs_ioctl_trans_start(file); 1277 case BTRFS_IOC_TRANS_END: 1278 return btrfs_ioctl_trans_end(file); 1279 case BTRFS_IOC_SYNC: 1280 btrfs_sync_fs(file->f_dentry->d_sb, 1); 1281 return 0; 1282 } 1283 1284 return -ENOTTY; 1285 } 1286