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 <linux/slab.h> 43 #include <linux/blkdev.h> 44 #include "compat.h" 45 #include "ctree.h" 46 #include "disk-io.h" 47 #include "transaction.h" 48 #include "btrfs_inode.h" 49 #include "ioctl.h" 50 #include "print-tree.h" 51 #include "volumes.h" 52 #include "locking.h" 53 #include "inode-map.h" 54 #include "backref.h" 55 56 /* Mask out flags that are inappropriate for the given type of inode. */ 57 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags) 58 { 59 if (S_ISDIR(mode)) 60 return flags; 61 else if (S_ISREG(mode)) 62 return flags & ~FS_DIRSYNC_FL; 63 else 64 return flags & (FS_NODUMP_FL | FS_NOATIME_FL); 65 } 66 67 /* 68 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl. 69 */ 70 static unsigned int btrfs_flags_to_ioctl(unsigned int flags) 71 { 72 unsigned int iflags = 0; 73 74 if (flags & BTRFS_INODE_SYNC) 75 iflags |= FS_SYNC_FL; 76 if (flags & BTRFS_INODE_IMMUTABLE) 77 iflags |= FS_IMMUTABLE_FL; 78 if (flags & BTRFS_INODE_APPEND) 79 iflags |= FS_APPEND_FL; 80 if (flags & BTRFS_INODE_NODUMP) 81 iflags |= FS_NODUMP_FL; 82 if (flags & BTRFS_INODE_NOATIME) 83 iflags |= FS_NOATIME_FL; 84 if (flags & BTRFS_INODE_DIRSYNC) 85 iflags |= FS_DIRSYNC_FL; 86 if (flags & BTRFS_INODE_NODATACOW) 87 iflags |= FS_NOCOW_FL; 88 89 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS)) 90 iflags |= FS_COMPR_FL; 91 else if (flags & BTRFS_INODE_NOCOMPRESS) 92 iflags |= FS_NOCOMP_FL; 93 94 return iflags; 95 } 96 97 /* 98 * Update inode->i_flags based on the btrfs internal flags. 99 */ 100 void btrfs_update_iflags(struct inode *inode) 101 { 102 struct btrfs_inode *ip = BTRFS_I(inode); 103 104 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); 105 106 if (ip->flags & BTRFS_INODE_SYNC) 107 inode->i_flags |= S_SYNC; 108 if (ip->flags & BTRFS_INODE_IMMUTABLE) 109 inode->i_flags |= S_IMMUTABLE; 110 if (ip->flags & BTRFS_INODE_APPEND) 111 inode->i_flags |= S_APPEND; 112 if (ip->flags & BTRFS_INODE_NOATIME) 113 inode->i_flags |= S_NOATIME; 114 if (ip->flags & BTRFS_INODE_DIRSYNC) 115 inode->i_flags |= S_DIRSYNC; 116 } 117 118 /* 119 * Inherit flags from the parent inode. 120 * 121 * Currently only the compression flags and the cow flags are inherited. 122 */ 123 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) 124 { 125 unsigned int flags; 126 127 if (!dir) 128 return; 129 130 flags = BTRFS_I(dir)->flags; 131 132 if (flags & BTRFS_INODE_NOCOMPRESS) { 133 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS; 134 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; 135 } else if (flags & BTRFS_INODE_COMPRESS) { 136 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS; 137 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS; 138 } 139 140 if (flags & BTRFS_INODE_NODATACOW) 141 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; 142 143 btrfs_update_iflags(inode); 144 } 145 146 static int btrfs_ioctl_getflags(struct file *file, void __user *arg) 147 { 148 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode); 149 unsigned int flags = btrfs_flags_to_ioctl(ip->flags); 150 151 if (copy_to_user(arg, &flags, sizeof(flags))) 152 return -EFAULT; 153 return 0; 154 } 155 156 static int check_flags(unsigned int flags) 157 { 158 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ 159 FS_NOATIME_FL | FS_NODUMP_FL | \ 160 FS_SYNC_FL | FS_DIRSYNC_FL | \ 161 FS_NOCOMP_FL | FS_COMPR_FL | 162 FS_NOCOW_FL)) 163 return -EOPNOTSUPP; 164 165 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) 166 return -EINVAL; 167 168 return 0; 169 } 170 171 static int btrfs_ioctl_setflags(struct file *file, void __user *arg) 172 { 173 struct inode *inode = file->f_path.dentry->d_inode; 174 struct btrfs_inode *ip = BTRFS_I(inode); 175 struct btrfs_root *root = ip->root; 176 struct btrfs_trans_handle *trans; 177 unsigned int flags, oldflags; 178 int ret; 179 u64 ip_oldflags; 180 unsigned int i_oldflags; 181 182 if (btrfs_root_readonly(root)) 183 return -EROFS; 184 185 if (copy_from_user(&flags, arg, sizeof(flags))) 186 return -EFAULT; 187 188 ret = check_flags(flags); 189 if (ret) 190 return ret; 191 192 if (!inode_owner_or_capable(inode)) 193 return -EACCES; 194 195 mutex_lock(&inode->i_mutex); 196 197 ip_oldflags = ip->flags; 198 i_oldflags = inode->i_flags; 199 200 flags = btrfs_mask_flags(inode->i_mode, flags); 201 oldflags = btrfs_flags_to_ioctl(ip->flags); 202 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { 203 if (!capable(CAP_LINUX_IMMUTABLE)) { 204 ret = -EPERM; 205 goto out_unlock; 206 } 207 } 208 209 ret = mnt_want_write(file->f_path.mnt); 210 if (ret) 211 goto out_unlock; 212 213 if (flags & FS_SYNC_FL) 214 ip->flags |= BTRFS_INODE_SYNC; 215 else 216 ip->flags &= ~BTRFS_INODE_SYNC; 217 if (flags & FS_IMMUTABLE_FL) 218 ip->flags |= BTRFS_INODE_IMMUTABLE; 219 else 220 ip->flags &= ~BTRFS_INODE_IMMUTABLE; 221 if (flags & FS_APPEND_FL) 222 ip->flags |= BTRFS_INODE_APPEND; 223 else 224 ip->flags &= ~BTRFS_INODE_APPEND; 225 if (flags & FS_NODUMP_FL) 226 ip->flags |= BTRFS_INODE_NODUMP; 227 else 228 ip->flags &= ~BTRFS_INODE_NODUMP; 229 if (flags & FS_NOATIME_FL) 230 ip->flags |= BTRFS_INODE_NOATIME; 231 else 232 ip->flags &= ~BTRFS_INODE_NOATIME; 233 if (flags & FS_DIRSYNC_FL) 234 ip->flags |= BTRFS_INODE_DIRSYNC; 235 else 236 ip->flags &= ~BTRFS_INODE_DIRSYNC; 237 if (flags & FS_NOCOW_FL) 238 ip->flags |= BTRFS_INODE_NODATACOW; 239 else 240 ip->flags &= ~BTRFS_INODE_NODATACOW; 241 242 /* 243 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS 244 * flag may be changed automatically if compression code won't make 245 * things smaller. 246 */ 247 if (flags & FS_NOCOMP_FL) { 248 ip->flags &= ~BTRFS_INODE_COMPRESS; 249 ip->flags |= BTRFS_INODE_NOCOMPRESS; 250 } else if (flags & FS_COMPR_FL) { 251 ip->flags |= BTRFS_INODE_COMPRESS; 252 ip->flags &= ~BTRFS_INODE_NOCOMPRESS; 253 } else { 254 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); 255 } 256 257 trans = btrfs_start_transaction(root, 1); 258 if (IS_ERR(trans)) { 259 ret = PTR_ERR(trans); 260 goto out_drop; 261 } 262 263 btrfs_update_iflags(inode); 264 inode->i_ctime = CURRENT_TIME; 265 ret = btrfs_update_inode(trans, root, inode); 266 267 btrfs_end_transaction(trans, root); 268 out_drop: 269 if (ret) { 270 ip->flags = ip_oldflags; 271 inode->i_flags = i_oldflags; 272 } 273 274 mnt_drop_write(file->f_path.mnt); 275 out_unlock: 276 mutex_unlock(&inode->i_mutex); 277 return ret; 278 } 279 280 static int btrfs_ioctl_getversion(struct file *file, int __user *arg) 281 { 282 struct inode *inode = file->f_path.dentry->d_inode; 283 284 return put_user(inode->i_generation, arg); 285 } 286 287 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) 288 { 289 struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info; 290 struct btrfs_fs_info *fs_info = root->fs_info; 291 struct btrfs_device *device; 292 struct request_queue *q; 293 struct fstrim_range range; 294 u64 minlen = ULLONG_MAX; 295 u64 num_devices = 0; 296 u64 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); 297 int ret; 298 299 if (!capable(CAP_SYS_ADMIN)) 300 return -EPERM; 301 302 rcu_read_lock(); 303 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices, 304 dev_list) { 305 if (!device->bdev) 306 continue; 307 q = bdev_get_queue(device->bdev); 308 if (blk_queue_discard(q)) { 309 num_devices++; 310 minlen = min((u64)q->limits.discard_granularity, 311 minlen); 312 } 313 } 314 rcu_read_unlock(); 315 316 if (!num_devices) 317 return -EOPNOTSUPP; 318 if (copy_from_user(&range, arg, sizeof(range))) 319 return -EFAULT; 320 if (range.start > total_bytes) 321 return -EINVAL; 322 323 range.len = min(range.len, total_bytes - range.start); 324 range.minlen = max(range.minlen, minlen); 325 ret = btrfs_trim_fs(root, &range); 326 if (ret < 0) 327 return ret; 328 329 if (copy_to_user(arg, &range, sizeof(range))) 330 return -EFAULT; 331 332 return 0; 333 } 334 335 static noinline int create_subvol(struct btrfs_root *root, 336 struct dentry *dentry, 337 char *name, int namelen, 338 u64 *async_transid) 339 { 340 struct btrfs_trans_handle *trans; 341 struct btrfs_key key; 342 struct btrfs_root_item root_item; 343 struct btrfs_inode_item *inode_item; 344 struct extent_buffer *leaf; 345 struct btrfs_root *new_root; 346 struct dentry *parent = dentry->d_parent; 347 struct inode *dir; 348 int ret; 349 int err; 350 u64 objectid; 351 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; 352 u64 index = 0; 353 354 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid); 355 if (ret) 356 return ret; 357 358 dir = parent->d_inode; 359 360 /* 361 * 1 - inode item 362 * 2 - refs 363 * 1 - root item 364 * 2 - dir items 365 */ 366 trans = btrfs_start_transaction(root, 6); 367 if (IS_ERR(trans)) 368 return PTR_ERR(trans); 369 370 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 371 0, objectid, NULL, 0, 0, 0, 0); 372 if (IS_ERR(leaf)) { 373 ret = PTR_ERR(leaf); 374 goto fail; 375 } 376 377 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header)); 378 btrfs_set_header_bytenr(leaf, leaf->start); 379 btrfs_set_header_generation(leaf, trans->transid); 380 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV); 381 btrfs_set_header_owner(leaf, objectid); 382 383 write_extent_buffer(leaf, root->fs_info->fsid, 384 (unsigned long)btrfs_header_fsid(leaf), 385 BTRFS_FSID_SIZE); 386 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 387 (unsigned long)btrfs_header_chunk_tree_uuid(leaf), 388 BTRFS_UUID_SIZE); 389 btrfs_mark_buffer_dirty(leaf); 390 391 inode_item = &root_item.inode; 392 memset(inode_item, 0, sizeof(*inode_item)); 393 inode_item->generation = cpu_to_le64(1); 394 inode_item->size = cpu_to_le64(3); 395 inode_item->nlink = cpu_to_le32(1); 396 inode_item->nbytes = cpu_to_le64(root->leafsize); 397 inode_item->mode = cpu_to_le32(S_IFDIR | 0755); 398 399 root_item.flags = 0; 400 root_item.byte_limit = 0; 401 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT); 402 403 btrfs_set_root_bytenr(&root_item, leaf->start); 404 btrfs_set_root_generation(&root_item, trans->transid); 405 btrfs_set_root_level(&root_item, 0); 406 btrfs_set_root_refs(&root_item, 1); 407 btrfs_set_root_used(&root_item, leaf->len); 408 btrfs_set_root_last_snapshot(&root_item, 0); 409 410 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress)); 411 root_item.drop_level = 0; 412 413 btrfs_tree_unlock(leaf); 414 free_extent_buffer(leaf); 415 leaf = NULL; 416 417 btrfs_set_root_dirid(&root_item, new_dirid); 418 419 key.objectid = objectid; 420 key.offset = 0; 421 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); 422 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, 423 &root_item); 424 if (ret) 425 goto fail; 426 427 key.offset = (u64)-1; 428 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); 429 BUG_ON(IS_ERR(new_root)); 430 431 btrfs_record_root_in_trans(trans, new_root); 432 433 ret = btrfs_create_subvol_root(trans, new_root, new_dirid); 434 /* 435 * insert the directory item 436 */ 437 ret = btrfs_set_inode_index(dir, &index); 438 BUG_ON(ret); 439 440 ret = btrfs_insert_dir_item(trans, root, 441 name, namelen, dir, &key, 442 BTRFS_FT_DIR, index); 443 if (ret) 444 goto fail; 445 446 btrfs_i_size_write(dir, dir->i_size + namelen * 2); 447 ret = btrfs_update_inode(trans, root, dir); 448 BUG_ON(ret); 449 450 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, 451 objectid, root->root_key.objectid, 452 btrfs_ino(dir), index, name, namelen); 453 454 BUG_ON(ret); 455 456 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry)); 457 fail: 458 if (async_transid) { 459 *async_transid = trans->transid; 460 err = btrfs_commit_transaction_async(trans, root, 1); 461 } else { 462 err = btrfs_commit_transaction(trans, root); 463 } 464 if (err && !ret) 465 ret = err; 466 return ret; 467 } 468 469 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry, 470 char *name, int namelen, u64 *async_transid, 471 bool readonly) 472 { 473 struct inode *inode; 474 struct btrfs_pending_snapshot *pending_snapshot; 475 struct btrfs_trans_handle *trans; 476 int ret; 477 478 if (!root->ref_cows) 479 return -EINVAL; 480 481 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); 482 if (!pending_snapshot) 483 return -ENOMEM; 484 485 btrfs_init_block_rsv(&pending_snapshot->block_rsv); 486 pending_snapshot->dentry = dentry; 487 pending_snapshot->root = root; 488 pending_snapshot->readonly = readonly; 489 490 trans = btrfs_start_transaction(root->fs_info->extent_root, 5); 491 if (IS_ERR(trans)) { 492 ret = PTR_ERR(trans); 493 goto fail; 494 } 495 496 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot); 497 BUG_ON(ret); 498 499 spin_lock(&root->fs_info->trans_lock); 500 list_add(&pending_snapshot->list, 501 &trans->transaction->pending_snapshots); 502 spin_unlock(&root->fs_info->trans_lock); 503 if (async_transid) { 504 *async_transid = trans->transid; 505 ret = btrfs_commit_transaction_async(trans, 506 root->fs_info->extent_root, 1); 507 } else { 508 ret = btrfs_commit_transaction(trans, 509 root->fs_info->extent_root); 510 } 511 BUG_ON(ret); 512 513 ret = pending_snapshot->error; 514 if (ret) 515 goto fail; 516 517 ret = btrfs_orphan_cleanup(pending_snapshot->snap); 518 if (ret) 519 goto fail; 520 521 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry); 522 if (IS_ERR(inode)) { 523 ret = PTR_ERR(inode); 524 goto fail; 525 } 526 BUG_ON(!inode); 527 d_instantiate(dentry, inode); 528 ret = 0; 529 fail: 530 kfree(pending_snapshot); 531 return ret; 532 } 533 534 /* copy of check_sticky in fs/namei.c() 535 * It's inline, so penalty for filesystems that don't use sticky bit is 536 * minimal. 537 */ 538 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode) 539 { 540 uid_t fsuid = current_fsuid(); 541 542 if (!(dir->i_mode & S_ISVTX)) 543 return 0; 544 if (inode->i_uid == fsuid) 545 return 0; 546 if (dir->i_uid == fsuid) 547 return 0; 548 return !capable(CAP_FOWNER); 549 } 550 551 /* copy of may_delete in fs/namei.c() 552 * Check whether we can remove a link victim from directory dir, check 553 * whether the type of victim is right. 554 * 1. We can't do it if dir is read-only (done in permission()) 555 * 2. We should have write and exec permissions on dir 556 * 3. We can't remove anything from append-only dir 557 * 4. We can't do anything with immutable dir (done in permission()) 558 * 5. If the sticky bit on dir is set we should either 559 * a. be owner of dir, or 560 * b. be owner of victim, or 561 * c. have CAP_FOWNER capability 562 * 6. If the victim is append-only or immutable we can't do antyhing with 563 * links pointing to it. 564 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. 565 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. 566 * 9. We can't remove a root or mountpoint. 567 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by 568 * nfs_async_unlink(). 569 */ 570 571 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir) 572 { 573 int error; 574 575 if (!victim->d_inode) 576 return -ENOENT; 577 578 BUG_ON(victim->d_parent->d_inode != dir); 579 audit_inode_child(victim, dir); 580 581 error = inode_permission(dir, MAY_WRITE | MAY_EXEC); 582 if (error) 583 return error; 584 if (IS_APPEND(dir)) 585 return -EPERM; 586 if (btrfs_check_sticky(dir, victim->d_inode)|| 587 IS_APPEND(victim->d_inode)|| 588 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) 589 return -EPERM; 590 if (isdir) { 591 if (!S_ISDIR(victim->d_inode->i_mode)) 592 return -ENOTDIR; 593 if (IS_ROOT(victim)) 594 return -EBUSY; 595 } else if (S_ISDIR(victim->d_inode->i_mode)) 596 return -EISDIR; 597 if (IS_DEADDIR(dir)) 598 return -ENOENT; 599 if (victim->d_flags & DCACHE_NFSFS_RENAMED) 600 return -EBUSY; 601 return 0; 602 } 603 604 /* copy of may_create in fs/namei.c() */ 605 static inline int btrfs_may_create(struct inode *dir, struct dentry *child) 606 { 607 if (child->d_inode) 608 return -EEXIST; 609 if (IS_DEADDIR(dir)) 610 return -ENOENT; 611 return inode_permission(dir, MAY_WRITE | MAY_EXEC); 612 } 613 614 /* 615 * Create a new subvolume below @parent. This is largely modeled after 616 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup 617 * inside this filesystem so it's quite a bit simpler. 618 */ 619 static noinline int btrfs_mksubvol(struct path *parent, 620 char *name, int namelen, 621 struct btrfs_root *snap_src, 622 u64 *async_transid, bool readonly) 623 { 624 struct inode *dir = parent->dentry->d_inode; 625 struct dentry *dentry; 626 int error; 627 628 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 629 630 dentry = lookup_one_len(name, parent->dentry, namelen); 631 error = PTR_ERR(dentry); 632 if (IS_ERR(dentry)) 633 goto out_unlock; 634 635 error = -EEXIST; 636 if (dentry->d_inode) 637 goto out_dput; 638 639 error = mnt_want_write(parent->mnt); 640 if (error) 641 goto out_dput; 642 643 error = btrfs_may_create(dir, dentry); 644 if (error) 645 goto out_drop_write; 646 647 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 648 649 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) 650 goto out_up_read; 651 652 if (snap_src) { 653 error = create_snapshot(snap_src, dentry, 654 name, namelen, async_transid, readonly); 655 } else { 656 error = create_subvol(BTRFS_I(dir)->root, dentry, 657 name, namelen, async_transid); 658 } 659 if (!error) 660 fsnotify_mkdir(dir, dentry); 661 out_up_read: 662 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 663 out_drop_write: 664 mnt_drop_write(parent->mnt); 665 out_dput: 666 dput(dentry); 667 out_unlock: 668 mutex_unlock(&dir->i_mutex); 669 return error; 670 } 671 672 /* 673 * When we're defragging a range, we don't want to kick it off again 674 * if it is really just waiting for delalloc to send it down. 675 * If we find a nice big extent or delalloc range for the bytes in the 676 * file you want to defrag, we return 0 to let you know to skip this 677 * part of the file 678 */ 679 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh) 680 { 681 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 682 struct extent_map *em = NULL; 683 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 684 u64 end; 685 686 read_lock(&em_tree->lock); 687 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); 688 read_unlock(&em_tree->lock); 689 690 if (em) { 691 end = extent_map_end(em); 692 free_extent_map(em); 693 if (end - offset > thresh) 694 return 0; 695 } 696 /* if we already have a nice delalloc here, just stop */ 697 thresh /= 2; 698 end = count_range_bits(io_tree, &offset, offset + thresh, 699 thresh, EXTENT_DELALLOC, 1); 700 if (end >= thresh) 701 return 0; 702 return 1; 703 } 704 705 /* 706 * helper function to walk through a file and find extents 707 * newer than a specific transid, and smaller than thresh. 708 * 709 * This is used by the defragging code to find new and small 710 * extents 711 */ 712 static int find_new_extents(struct btrfs_root *root, 713 struct inode *inode, u64 newer_than, 714 u64 *off, int thresh) 715 { 716 struct btrfs_path *path; 717 struct btrfs_key min_key; 718 struct btrfs_key max_key; 719 struct extent_buffer *leaf; 720 struct btrfs_file_extent_item *extent; 721 int type; 722 int ret; 723 u64 ino = btrfs_ino(inode); 724 725 path = btrfs_alloc_path(); 726 if (!path) 727 return -ENOMEM; 728 729 min_key.objectid = ino; 730 min_key.type = BTRFS_EXTENT_DATA_KEY; 731 min_key.offset = *off; 732 733 max_key.objectid = ino; 734 max_key.type = (u8)-1; 735 max_key.offset = (u64)-1; 736 737 path->keep_locks = 1; 738 739 while(1) { 740 ret = btrfs_search_forward(root, &min_key, &max_key, 741 path, 0, newer_than); 742 if (ret != 0) 743 goto none; 744 if (min_key.objectid != ino) 745 goto none; 746 if (min_key.type != BTRFS_EXTENT_DATA_KEY) 747 goto none; 748 749 leaf = path->nodes[0]; 750 extent = btrfs_item_ptr(leaf, path->slots[0], 751 struct btrfs_file_extent_item); 752 753 type = btrfs_file_extent_type(leaf, extent); 754 if (type == BTRFS_FILE_EXTENT_REG && 755 btrfs_file_extent_num_bytes(leaf, extent) < thresh && 756 check_defrag_in_cache(inode, min_key.offset, thresh)) { 757 *off = min_key.offset; 758 btrfs_free_path(path); 759 return 0; 760 } 761 762 if (min_key.offset == (u64)-1) 763 goto none; 764 765 min_key.offset++; 766 btrfs_release_path(path); 767 } 768 none: 769 btrfs_free_path(path); 770 return -ENOENT; 771 } 772 773 static int should_defrag_range(struct inode *inode, u64 start, u64 len, 774 int thresh, u64 *last_len, u64 *skip, 775 u64 *defrag_end) 776 { 777 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 778 struct extent_map *em = NULL; 779 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 780 int ret = 1; 781 782 /* 783 * make sure that once we start defragging an extent, we keep on 784 * defragging it 785 */ 786 if (start < *defrag_end) 787 return 1; 788 789 *skip = 0; 790 791 /* 792 * hopefully we have this extent in the tree already, try without 793 * the full extent lock 794 */ 795 read_lock(&em_tree->lock); 796 em = lookup_extent_mapping(em_tree, start, len); 797 read_unlock(&em_tree->lock); 798 799 if (!em) { 800 /* get the big lock and read metadata off disk */ 801 lock_extent(io_tree, start, start + len - 1, GFP_NOFS); 802 em = btrfs_get_extent(inode, NULL, 0, start, len, 0); 803 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS); 804 805 if (IS_ERR(em)) 806 return 0; 807 } 808 809 /* this will cover holes, and inline extents */ 810 if (em->block_start >= EXTENT_MAP_LAST_BYTE) 811 ret = 0; 812 813 /* 814 * we hit a real extent, if it is big don't bother defragging it again 815 */ 816 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh) 817 ret = 0; 818 819 /* 820 * last_len ends up being a counter of how many bytes we've defragged. 821 * every time we choose not to defrag an extent, we reset *last_len 822 * so that the next tiny extent will force a defrag. 823 * 824 * The end result of this is that tiny extents before a single big 825 * extent will force at least part of that big extent to be defragged. 826 */ 827 if (ret) { 828 *defrag_end = extent_map_end(em); 829 } else { 830 *last_len = 0; 831 *skip = extent_map_end(em); 832 *defrag_end = 0; 833 } 834 835 free_extent_map(em); 836 return ret; 837 } 838 839 /* 840 * it doesn't do much good to defrag one or two pages 841 * at a time. This pulls in a nice chunk of pages 842 * to COW and defrag. 843 * 844 * It also makes sure the delalloc code has enough 845 * dirty data to avoid making new small extents as part 846 * of the defrag 847 * 848 * It's a good idea to start RA on this range 849 * before calling this. 850 */ 851 static int cluster_pages_for_defrag(struct inode *inode, 852 struct page **pages, 853 unsigned long start_index, 854 int num_pages) 855 { 856 unsigned long file_end; 857 u64 isize = i_size_read(inode); 858 u64 page_start; 859 u64 page_end; 860 int ret; 861 int i; 862 int i_done; 863 struct btrfs_ordered_extent *ordered; 864 struct extent_state *cached_state = NULL; 865 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 866 867 if (isize == 0) 868 return 0; 869 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 870 871 ret = btrfs_delalloc_reserve_space(inode, 872 num_pages << PAGE_CACHE_SHIFT); 873 if (ret) 874 return ret; 875 again: 876 ret = 0; 877 i_done = 0; 878 879 /* step one, lock all the pages */ 880 for (i = 0; i < num_pages; i++) { 881 struct page *page; 882 page = find_or_create_page(inode->i_mapping, 883 start_index + i, mask); 884 if (!page) 885 break; 886 887 if (!PageUptodate(page)) { 888 btrfs_readpage(NULL, page); 889 lock_page(page); 890 if (!PageUptodate(page)) { 891 unlock_page(page); 892 page_cache_release(page); 893 ret = -EIO; 894 break; 895 } 896 } 897 isize = i_size_read(inode); 898 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 899 if (!isize || page->index > file_end || 900 page->mapping != inode->i_mapping) { 901 /* whoops, we blew past eof, skip this page */ 902 unlock_page(page); 903 page_cache_release(page); 904 break; 905 } 906 pages[i] = page; 907 i_done++; 908 } 909 if (!i_done || ret) 910 goto out; 911 912 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 913 goto out; 914 915 /* 916 * so now we have a nice long stream of locked 917 * and up to date pages, lets wait on them 918 */ 919 for (i = 0; i < i_done; i++) 920 wait_on_page_writeback(pages[i]); 921 922 page_start = page_offset(pages[0]); 923 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; 924 925 lock_extent_bits(&BTRFS_I(inode)->io_tree, 926 page_start, page_end - 1, 0, &cached_state, 927 GFP_NOFS); 928 ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1); 929 if (ordered && 930 ordered->file_offset + ordered->len > page_start && 931 ordered->file_offset < page_end) { 932 btrfs_put_ordered_extent(ordered); 933 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 934 page_start, page_end - 1, 935 &cached_state, GFP_NOFS); 936 for (i = 0; i < i_done; i++) { 937 unlock_page(pages[i]); 938 page_cache_release(pages[i]); 939 } 940 btrfs_wait_ordered_range(inode, page_start, 941 page_end - page_start); 942 goto again; 943 } 944 if (ordered) 945 btrfs_put_ordered_extent(ordered); 946 947 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 948 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 949 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state, 950 GFP_NOFS); 951 952 if (i_done != num_pages) { 953 spin_lock(&BTRFS_I(inode)->lock); 954 BTRFS_I(inode)->outstanding_extents++; 955 spin_unlock(&BTRFS_I(inode)->lock); 956 btrfs_delalloc_release_space(inode, 957 (num_pages - i_done) << PAGE_CACHE_SHIFT); 958 } 959 960 961 btrfs_set_extent_delalloc(inode, page_start, page_end - 1, 962 &cached_state); 963 964 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 965 page_start, page_end - 1, &cached_state, 966 GFP_NOFS); 967 968 for (i = 0; i < i_done; i++) { 969 clear_page_dirty_for_io(pages[i]); 970 ClearPageChecked(pages[i]); 971 set_page_extent_mapped(pages[i]); 972 set_page_dirty(pages[i]); 973 unlock_page(pages[i]); 974 page_cache_release(pages[i]); 975 } 976 return i_done; 977 out: 978 for (i = 0; i < i_done; i++) { 979 unlock_page(pages[i]); 980 page_cache_release(pages[i]); 981 } 982 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT); 983 return ret; 984 985 } 986 987 int btrfs_defrag_file(struct inode *inode, struct file *file, 988 struct btrfs_ioctl_defrag_range_args *range, 989 u64 newer_than, unsigned long max_to_defrag) 990 { 991 struct btrfs_root *root = BTRFS_I(inode)->root; 992 struct btrfs_super_block *disk_super; 993 struct file_ra_state *ra = NULL; 994 unsigned long last_index; 995 u64 isize = i_size_read(inode); 996 u64 features; 997 u64 last_len = 0; 998 u64 skip = 0; 999 u64 defrag_end = 0; 1000 u64 newer_off = range->start; 1001 unsigned long i; 1002 unsigned long ra_index = 0; 1003 int ret; 1004 int defrag_count = 0; 1005 int compress_type = BTRFS_COMPRESS_ZLIB; 1006 int extent_thresh = range->extent_thresh; 1007 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; 1008 int cluster = max_cluster; 1009 u64 new_align = ~((u64)128 * 1024 - 1); 1010 struct page **pages = NULL; 1011 1012 if (extent_thresh == 0) 1013 extent_thresh = 256 * 1024; 1014 1015 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1016 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1017 return -EINVAL; 1018 if (range->compress_type) 1019 compress_type = range->compress_type; 1020 } 1021 1022 if (isize == 0) 1023 return 0; 1024 1025 /* 1026 * if we were not given a file, allocate a readahead 1027 * context 1028 */ 1029 if (!file) { 1030 ra = kzalloc(sizeof(*ra), GFP_NOFS); 1031 if (!ra) 1032 return -ENOMEM; 1033 file_ra_state_init(ra, inode->i_mapping); 1034 } else { 1035 ra = &file->f_ra; 1036 } 1037 1038 pages = kmalloc(sizeof(struct page *) * max_cluster, 1039 GFP_NOFS); 1040 if (!pages) { 1041 ret = -ENOMEM; 1042 goto out_ra; 1043 } 1044 1045 /* find the last page to defrag */ 1046 if (range->start + range->len > range->start) { 1047 last_index = min_t(u64, isize - 1, 1048 range->start + range->len - 1) >> PAGE_CACHE_SHIFT; 1049 } else { 1050 last_index = (isize - 1) >> PAGE_CACHE_SHIFT; 1051 } 1052 1053 if (newer_than) { 1054 ret = find_new_extents(root, inode, newer_than, 1055 &newer_off, 64 * 1024); 1056 if (!ret) { 1057 range->start = newer_off; 1058 /* 1059 * we always align our defrag to help keep 1060 * the extents in the file evenly spaced 1061 */ 1062 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1063 } else 1064 goto out_ra; 1065 } else { 1066 i = range->start >> PAGE_CACHE_SHIFT; 1067 } 1068 if (!max_to_defrag) 1069 max_to_defrag = last_index; 1070 1071 /* 1072 * make writeback starts from i, so the defrag range can be 1073 * written sequentially. 1074 */ 1075 if (i < inode->i_mapping->writeback_index) 1076 inode->i_mapping->writeback_index = i; 1077 1078 while (i <= last_index && defrag_count < max_to_defrag && 1079 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> 1080 PAGE_CACHE_SHIFT)) { 1081 /* 1082 * make sure we stop running if someone unmounts 1083 * the FS 1084 */ 1085 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1086 break; 1087 1088 if (!newer_than && 1089 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, 1090 PAGE_CACHE_SIZE, 1091 extent_thresh, 1092 &last_len, &skip, 1093 &defrag_end)) { 1094 unsigned long next; 1095 /* 1096 * the should_defrag function tells us how much to skip 1097 * bump our counter by the suggested amount 1098 */ 1099 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 1100 i = max(i + 1, next); 1101 continue; 1102 } 1103 1104 if (!newer_than) { 1105 cluster = (PAGE_CACHE_ALIGN(defrag_end) >> 1106 PAGE_CACHE_SHIFT) - i; 1107 cluster = min(cluster, max_cluster); 1108 } else { 1109 cluster = max_cluster; 1110 } 1111 1112 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) 1113 BTRFS_I(inode)->force_compress = compress_type; 1114 1115 if (i + cluster > ra_index) { 1116 ra_index = max(i, ra_index); 1117 btrfs_force_ra(inode->i_mapping, ra, file, ra_index, 1118 cluster); 1119 ra_index += max_cluster; 1120 } 1121 1122 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1123 if (ret < 0) 1124 goto out_ra; 1125 1126 defrag_count += ret; 1127 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret); 1128 1129 if (newer_than) { 1130 if (newer_off == (u64)-1) 1131 break; 1132 1133 newer_off = max(newer_off + 1, 1134 (u64)i << PAGE_CACHE_SHIFT); 1135 1136 ret = find_new_extents(root, inode, 1137 newer_than, &newer_off, 1138 64 * 1024); 1139 if (!ret) { 1140 range->start = newer_off; 1141 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1142 } else { 1143 break; 1144 } 1145 } else { 1146 if (ret > 0) { 1147 i += ret; 1148 last_len += ret << PAGE_CACHE_SHIFT; 1149 } else { 1150 i++; 1151 last_len = 0; 1152 } 1153 } 1154 } 1155 1156 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) 1157 filemap_flush(inode->i_mapping); 1158 1159 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 1160 /* the filemap_flush will queue IO into the worker threads, but 1161 * we have to make sure the IO is actually started and that 1162 * ordered extents get created before we return 1163 */ 1164 atomic_inc(&root->fs_info->async_submit_draining); 1165 while (atomic_read(&root->fs_info->nr_async_submits) || 1166 atomic_read(&root->fs_info->async_delalloc_pages)) { 1167 wait_event(root->fs_info->async_submit_wait, 1168 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 1169 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 1170 } 1171 atomic_dec(&root->fs_info->async_submit_draining); 1172 1173 mutex_lock(&inode->i_mutex); 1174 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; 1175 mutex_unlock(&inode->i_mutex); 1176 } 1177 1178 disk_super = root->fs_info->super_copy; 1179 features = btrfs_super_incompat_flags(disk_super); 1180 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1181 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO; 1182 btrfs_set_super_incompat_flags(disk_super, features); 1183 } 1184 1185 ret = defrag_count; 1186 1187 out_ra: 1188 if (!file) 1189 kfree(ra); 1190 kfree(pages); 1191 return ret; 1192 } 1193 1194 static noinline int btrfs_ioctl_resize(struct btrfs_root *root, 1195 void __user *arg) 1196 { 1197 u64 new_size; 1198 u64 old_size; 1199 u64 devid = 1; 1200 struct btrfs_ioctl_vol_args *vol_args; 1201 struct btrfs_trans_handle *trans; 1202 struct btrfs_device *device = NULL; 1203 char *sizestr; 1204 char *devstr = NULL; 1205 int ret = 0; 1206 int mod = 0; 1207 1208 if (root->fs_info->sb->s_flags & MS_RDONLY) 1209 return -EROFS; 1210 1211 if (!capable(CAP_SYS_ADMIN)) 1212 return -EPERM; 1213 1214 mutex_lock(&root->fs_info->volume_mutex); 1215 if (root->fs_info->balance_ctl) { 1216 printk(KERN_INFO "btrfs: balance in progress\n"); 1217 ret = -EINVAL; 1218 goto out; 1219 } 1220 1221 vol_args = memdup_user(arg, sizeof(*vol_args)); 1222 if (IS_ERR(vol_args)) { 1223 ret = PTR_ERR(vol_args); 1224 goto out; 1225 } 1226 1227 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1228 1229 sizestr = vol_args->name; 1230 devstr = strchr(sizestr, ':'); 1231 if (devstr) { 1232 char *end; 1233 sizestr = devstr + 1; 1234 *devstr = '\0'; 1235 devstr = vol_args->name; 1236 devid = simple_strtoull(devstr, &end, 10); 1237 printk(KERN_INFO "btrfs: resizing devid %llu\n", 1238 (unsigned long long)devid); 1239 } 1240 device = btrfs_find_device(root, devid, NULL, NULL); 1241 if (!device) { 1242 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n", 1243 (unsigned long long)devid); 1244 ret = -EINVAL; 1245 goto out_free; 1246 } 1247 if (!strcmp(sizestr, "max")) 1248 new_size = device->bdev->bd_inode->i_size; 1249 else { 1250 if (sizestr[0] == '-') { 1251 mod = -1; 1252 sizestr++; 1253 } else if (sizestr[0] == '+') { 1254 mod = 1; 1255 sizestr++; 1256 } 1257 new_size = memparse(sizestr, NULL); 1258 if (new_size == 0) { 1259 ret = -EINVAL; 1260 goto out_free; 1261 } 1262 } 1263 1264 old_size = device->total_bytes; 1265 1266 if (mod < 0) { 1267 if (new_size > old_size) { 1268 ret = -EINVAL; 1269 goto out_free; 1270 } 1271 new_size = old_size - new_size; 1272 } else if (mod > 0) { 1273 new_size = old_size + new_size; 1274 } 1275 1276 if (new_size < 256 * 1024 * 1024) { 1277 ret = -EINVAL; 1278 goto out_free; 1279 } 1280 if (new_size > device->bdev->bd_inode->i_size) { 1281 ret = -EFBIG; 1282 goto out_free; 1283 } 1284 1285 do_div(new_size, root->sectorsize); 1286 new_size *= root->sectorsize; 1287 1288 printk(KERN_INFO "btrfs: new size for %s is %llu\n", 1289 device->name, (unsigned long long)new_size); 1290 1291 if (new_size > old_size) { 1292 trans = btrfs_start_transaction(root, 0); 1293 if (IS_ERR(trans)) { 1294 ret = PTR_ERR(trans); 1295 goto out_free; 1296 } 1297 ret = btrfs_grow_device(trans, device, new_size); 1298 btrfs_commit_transaction(trans, root); 1299 } else if (new_size < old_size) { 1300 ret = btrfs_shrink_device(device, new_size); 1301 } 1302 1303 out_free: 1304 kfree(vol_args); 1305 out: 1306 mutex_unlock(&root->fs_info->volume_mutex); 1307 return ret; 1308 } 1309 1310 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1311 char *name, 1312 unsigned long fd, 1313 int subvol, 1314 u64 *transid, 1315 bool readonly) 1316 { 1317 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 1318 struct file *src_file; 1319 int namelen; 1320 int ret = 0; 1321 1322 if (root->fs_info->sb->s_flags & MS_RDONLY) 1323 return -EROFS; 1324 1325 namelen = strlen(name); 1326 if (strchr(name, '/')) { 1327 ret = -EINVAL; 1328 goto out; 1329 } 1330 1331 if (subvol) { 1332 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1333 NULL, transid, readonly); 1334 } else { 1335 struct inode *src_inode; 1336 src_file = fget(fd); 1337 if (!src_file) { 1338 ret = -EINVAL; 1339 goto out; 1340 } 1341 1342 src_inode = src_file->f_path.dentry->d_inode; 1343 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { 1344 printk(KERN_INFO "btrfs: Snapshot src from " 1345 "another FS\n"); 1346 ret = -EINVAL; 1347 fput(src_file); 1348 goto out; 1349 } 1350 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1351 BTRFS_I(src_inode)->root, 1352 transid, readonly); 1353 fput(src_file); 1354 } 1355 out: 1356 return ret; 1357 } 1358 1359 static noinline int btrfs_ioctl_snap_create(struct file *file, 1360 void __user *arg, int subvol) 1361 { 1362 struct btrfs_ioctl_vol_args *vol_args; 1363 int ret; 1364 1365 vol_args = memdup_user(arg, sizeof(*vol_args)); 1366 if (IS_ERR(vol_args)) 1367 return PTR_ERR(vol_args); 1368 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1369 1370 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1371 vol_args->fd, subvol, 1372 NULL, false); 1373 1374 kfree(vol_args); 1375 return ret; 1376 } 1377 1378 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1379 void __user *arg, int subvol) 1380 { 1381 struct btrfs_ioctl_vol_args_v2 *vol_args; 1382 int ret; 1383 u64 transid = 0; 1384 u64 *ptr = NULL; 1385 bool readonly = false; 1386 1387 vol_args = memdup_user(arg, sizeof(*vol_args)); 1388 if (IS_ERR(vol_args)) 1389 return PTR_ERR(vol_args); 1390 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1391 1392 if (vol_args->flags & 1393 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) { 1394 ret = -EOPNOTSUPP; 1395 goto out; 1396 } 1397 1398 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1399 ptr = &transid; 1400 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1401 readonly = true; 1402 1403 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1404 vol_args->fd, subvol, 1405 ptr, readonly); 1406 1407 if (ret == 0 && ptr && 1408 copy_to_user(arg + 1409 offsetof(struct btrfs_ioctl_vol_args_v2, 1410 transid), ptr, sizeof(*ptr))) 1411 ret = -EFAULT; 1412 out: 1413 kfree(vol_args); 1414 return ret; 1415 } 1416 1417 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1418 void __user *arg) 1419 { 1420 struct inode *inode = fdentry(file)->d_inode; 1421 struct btrfs_root *root = BTRFS_I(inode)->root; 1422 int ret = 0; 1423 u64 flags = 0; 1424 1425 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1426 return -EINVAL; 1427 1428 down_read(&root->fs_info->subvol_sem); 1429 if (btrfs_root_readonly(root)) 1430 flags |= BTRFS_SUBVOL_RDONLY; 1431 up_read(&root->fs_info->subvol_sem); 1432 1433 if (copy_to_user(arg, &flags, sizeof(flags))) 1434 ret = -EFAULT; 1435 1436 return ret; 1437 } 1438 1439 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1440 void __user *arg) 1441 { 1442 struct inode *inode = fdentry(file)->d_inode; 1443 struct btrfs_root *root = BTRFS_I(inode)->root; 1444 struct btrfs_trans_handle *trans; 1445 u64 root_flags; 1446 u64 flags; 1447 int ret = 0; 1448 1449 if (root->fs_info->sb->s_flags & MS_RDONLY) 1450 return -EROFS; 1451 1452 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1453 return -EINVAL; 1454 1455 if (copy_from_user(&flags, arg, sizeof(flags))) 1456 return -EFAULT; 1457 1458 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) 1459 return -EINVAL; 1460 1461 if (flags & ~BTRFS_SUBVOL_RDONLY) 1462 return -EOPNOTSUPP; 1463 1464 if (!inode_owner_or_capable(inode)) 1465 return -EACCES; 1466 1467 down_write(&root->fs_info->subvol_sem); 1468 1469 /* nothing to do */ 1470 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1471 goto out; 1472 1473 root_flags = btrfs_root_flags(&root->root_item); 1474 if (flags & BTRFS_SUBVOL_RDONLY) 1475 btrfs_set_root_flags(&root->root_item, 1476 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1477 else 1478 btrfs_set_root_flags(&root->root_item, 1479 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1480 1481 trans = btrfs_start_transaction(root, 1); 1482 if (IS_ERR(trans)) { 1483 ret = PTR_ERR(trans); 1484 goto out_reset; 1485 } 1486 1487 ret = btrfs_update_root(trans, root->fs_info->tree_root, 1488 &root->root_key, &root->root_item); 1489 1490 btrfs_commit_transaction(trans, root); 1491 out_reset: 1492 if (ret) 1493 btrfs_set_root_flags(&root->root_item, root_flags); 1494 out: 1495 up_write(&root->fs_info->subvol_sem); 1496 return ret; 1497 } 1498 1499 /* 1500 * helper to check if the subvolume references other subvolumes 1501 */ 1502 static noinline int may_destroy_subvol(struct btrfs_root *root) 1503 { 1504 struct btrfs_path *path; 1505 struct btrfs_key key; 1506 int ret; 1507 1508 path = btrfs_alloc_path(); 1509 if (!path) 1510 return -ENOMEM; 1511 1512 key.objectid = root->root_key.objectid; 1513 key.type = BTRFS_ROOT_REF_KEY; 1514 key.offset = (u64)-1; 1515 1516 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, 1517 &key, path, 0, 0); 1518 if (ret < 0) 1519 goto out; 1520 BUG_ON(ret == 0); 1521 1522 ret = 0; 1523 if (path->slots[0] > 0) { 1524 path->slots[0]--; 1525 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 1526 if (key.objectid == root->root_key.objectid && 1527 key.type == BTRFS_ROOT_REF_KEY) 1528 ret = -ENOTEMPTY; 1529 } 1530 out: 1531 btrfs_free_path(path); 1532 return ret; 1533 } 1534 1535 static noinline int key_in_sk(struct btrfs_key *key, 1536 struct btrfs_ioctl_search_key *sk) 1537 { 1538 struct btrfs_key test; 1539 int ret; 1540 1541 test.objectid = sk->min_objectid; 1542 test.type = sk->min_type; 1543 test.offset = sk->min_offset; 1544 1545 ret = btrfs_comp_cpu_keys(key, &test); 1546 if (ret < 0) 1547 return 0; 1548 1549 test.objectid = sk->max_objectid; 1550 test.type = sk->max_type; 1551 test.offset = sk->max_offset; 1552 1553 ret = btrfs_comp_cpu_keys(key, &test); 1554 if (ret > 0) 1555 return 0; 1556 return 1; 1557 } 1558 1559 static noinline int copy_to_sk(struct btrfs_root *root, 1560 struct btrfs_path *path, 1561 struct btrfs_key *key, 1562 struct btrfs_ioctl_search_key *sk, 1563 char *buf, 1564 unsigned long *sk_offset, 1565 int *num_found) 1566 { 1567 u64 found_transid; 1568 struct extent_buffer *leaf; 1569 struct btrfs_ioctl_search_header sh; 1570 unsigned long item_off; 1571 unsigned long item_len; 1572 int nritems; 1573 int i; 1574 int slot; 1575 int ret = 0; 1576 1577 leaf = path->nodes[0]; 1578 slot = path->slots[0]; 1579 nritems = btrfs_header_nritems(leaf); 1580 1581 if (btrfs_header_generation(leaf) > sk->max_transid) { 1582 i = nritems; 1583 goto advance_key; 1584 } 1585 found_transid = btrfs_header_generation(leaf); 1586 1587 for (i = slot; i < nritems; i++) { 1588 item_off = btrfs_item_ptr_offset(leaf, i); 1589 item_len = btrfs_item_size_nr(leaf, i); 1590 1591 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) 1592 item_len = 0; 1593 1594 if (sizeof(sh) + item_len + *sk_offset > 1595 BTRFS_SEARCH_ARGS_BUFSIZE) { 1596 ret = 1; 1597 goto overflow; 1598 } 1599 1600 btrfs_item_key_to_cpu(leaf, key, i); 1601 if (!key_in_sk(key, sk)) 1602 continue; 1603 1604 sh.objectid = key->objectid; 1605 sh.offset = key->offset; 1606 sh.type = key->type; 1607 sh.len = item_len; 1608 sh.transid = found_transid; 1609 1610 /* copy search result header */ 1611 memcpy(buf + *sk_offset, &sh, sizeof(sh)); 1612 *sk_offset += sizeof(sh); 1613 1614 if (item_len) { 1615 char *p = buf + *sk_offset; 1616 /* copy the item */ 1617 read_extent_buffer(leaf, p, 1618 item_off, item_len); 1619 *sk_offset += item_len; 1620 } 1621 (*num_found)++; 1622 1623 if (*num_found >= sk->nr_items) 1624 break; 1625 } 1626 advance_key: 1627 ret = 0; 1628 if (key->offset < (u64)-1 && key->offset < sk->max_offset) 1629 key->offset++; 1630 else if (key->type < (u8)-1 && key->type < sk->max_type) { 1631 key->offset = 0; 1632 key->type++; 1633 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { 1634 key->offset = 0; 1635 key->type = 0; 1636 key->objectid++; 1637 } else 1638 ret = 1; 1639 overflow: 1640 return ret; 1641 } 1642 1643 static noinline int search_ioctl(struct inode *inode, 1644 struct btrfs_ioctl_search_args *args) 1645 { 1646 struct btrfs_root *root; 1647 struct btrfs_key key; 1648 struct btrfs_key max_key; 1649 struct btrfs_path *path; 1650 struct btrfs_ioctl_search_key *sk = &args->key; 1651 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; 1652 int ret; 1653 int num_found = 0; 1654 unsigned long sk_offset = 0; 1655 1656 path = btrfs_alloc_path(); 1657 if (!path) 1658 return -ENOMEM; 1659 1660 if (sk->tree_id == 0) { 1661 /* search the root of the inode that was passed */ 1662 root = BTRFS_I(inode)->root; 1663 } else { 1664 key.objectid = sk->tree_id; 1665 key.type = BTRFS_ROOT_ITEM_KEY; 1666 key.offset = (u64)-1; 1667 root = btrfs_read_fs_root_no_name(info, &key); 1668 if (IS_ERR(root)) { 1669 printk(KERN_ERR "could not find root %llu\n", 1670 sk->tree_id); 1671 btrfs_free_path(path); 1672 return -ENOENT; 1673 } 1674 } 1675 1676 key.objectid = sk->min_objectid; 1677 key.type = sk->min_type; 1678 key.offset = sk->min_offset; 1679 1680 max_key.objectid = sk->max_objectid; 1681 max_key.type = sk->max_type; 1682 max_key.offset = sk->max_offset; 1683 1684 path->keep_locks = 1; 1685 1686 while(1) { 1687 ret = btrfs_search_forward(root, &key, &max_key, path, 0, 1688 sk->min_transid); 1689 if (ret != 0) { 1690 if (ret > 0) 1691 ret = 0; 1692 goto err; 1693 } 1694 ret = copy_to_sk(root, path, &key, sk, args->buf, 1695 &sk_offset, &num_found); 1696 btrfs_release_path(path); 1697 if (ret || num_found >= sk->nr_items) 1698 break; 1699 1700 } 1701 ret = 0; 1702 err: 1703 sk->nr_items = num_found; 1704 btrfs_free_path(path); 1705 return ret; 1706 } 1707 1708 static noinline int btrfs_ioctl_tree_search(struct file *file, 1709 void __user *argp) 1710 { 1711 struct btrfs_ioctl_search_args *args; 1712 struct inode *inode; 1713 int ret; 1714 1715 if (!capable(CAP_SYS_ADMIN)) 1716 return -EPERM; 1717 1718 args = memdup_user(argp, sizeof(*args)); 1719 if (IS_ERR(args)) 1720 return PTR_ERR(args); 1721 1722 inode = fdentry(file)->d_inode; 1723 ret = search_ioctl(inode, args); 1724 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1725 ret = -EFAULT; 1726 kfree(args); 1727 return ret; 1728 } 1729 1730 /* 1731 * Search INODE_REFs to identify path name of 'dirid' directory 1732 * in a 'tree_id' tree. and sets path name to 'name'. 1733 */ 1734 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 1735 u64 tree_id, u64 dirid, char *name) 1736 { 1737 struct btrfs_root *root; 1738 struct btrfs_key key; 1739 char *ptr; 1740 int ret = -1; 1741 int slot; 1742 int len; 1743 int total_len = 0; 1744 struct btrfs_inode_ref *iref; 1745 struct extent_buffer *l; 1746 struct btrfs_path *path; 1747 1748 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 1749 name[0]='\0'; 1750 return 0; 1751 } 1752 1753 path = btrfs_alloc_path(); 1754 if (!path) 1755 return -ENOMEM; 1756 1757 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; 1758 1759 key.objectid = tree_id; 1760 key.type = BTRFS_ROOT_ITEM_KEY; 1761 key.offset = (u64)-1; 1762 root = btrfs_read_fs_root_no_name(info, &key); 1763 if (IS_ERR(root)) { 1764 printk(KERN_ERR "could not find root %llu\n", tree_id); 1765 ret = -ENOENT; 1766 goto out; 1767 } 1768 1769 key.objectid = dirid; 1770 key.type = BTRFS_INODE_REF_KEY; 1771 key.offset = (u64)-1; 1772 1773 while(1) { 1774 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1775 if (ret < 0) 1776 goto out; 1777 1778 l = path->nodes[0]; 1779 slot = path->slots[0]; 1780 if (ret > 0 && slot > 0) 1781 slot--; 1782 btrfs_item_key_to_cpu(l, &key, slot); 1783 1784 if (ret > 0 && (key.objectid != dirid || 1785 key.type != BTRFS_INODE_REF_KEY)) { 1786 ret = -ENOENT; 1787 goto out; 1788 } 1789 1790 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 1791 len = btrfs_inode_ref_name_len(l, iref); 1792 ptr -= len + 1; 1793 total_len += len + 1; 1794 if (ptr < name) 1795 goto out; 1796 1797 *(ptr + len) = '/'; 1798 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len); 1799 1800 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 1801 break; 1802 1803 btrfs_release_path(path); 1804 key.objectid = key.offset; 1805 key.offset = (u64)-1; 1806 dirid = key.objectid; 1807 } 1808 if (ptr < name) 1809 goto out; 1810 memmove(name, ptr, total_len); 1811 name[total_len]='\0'; 1812 ret = 0; 1813 out: 1814 btrfs_free_path(path); 1815 return ret; 1816 } 1817 1818 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 1819 void __user *argp) 1820 { 1821 struct btrfs_ioctl_ino_lookup_args *args; 1822 struct inode *inode; 1823 int ret; 1824 1825 if (!capable(CAP_SYS_ADMIN)) 1826 return -EPERM; 1827 1828 args = memdup_user(argp, sizeof(*args)); 1829 if (IS_ERR(args)) 1830 return PTR_ERR(args); 1831 1832 inode = fdentry(file)->d_inode; 1833 1834 if (args->treeid == 0) 1835 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 1836 1837 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 1838 args->treeid, args->objectid, 1839 args->name); 1840 1841 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1842 ret = -EFAULT; 1843 1844 kfree(args); 1845 return ret; 1846 } 1847 1848 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 1849 void __user *arg) 1850 { 1851 struct dentry *parent = fdentry(file); 1852 struct dentry *dentry; 1853 struct inode *dir = parent->d_inode; 1854 struct inode *inode; 1855 struct btrfs_root *root = BTRFS_I(dir)->root; 1856 struct btrfs_root *dest = NULL; 1857 struct btrfs_ioctl_vol_args *vol_args; 1858 struct btrfs_trans_handle *trans; 1859 int namelen; 1860 int ret; 1861 int err = 0; 1862 1863 vol_args = memdup_user(arg, sizeof(*vol_args)); 1864 if (IS_ERR(vol_args)) 1865 return PTR_ERR(vol_args); 1866 1867 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1868 namelen = strlen(vol_args->name); 1869 if (strchr(vol_args->name, '/') || 1870 strncmp(vol_args->name, "..", namelen) == 0) { 1871 err = -EINVAL; 1872 goto out; 1873 } 1874 1875 err = mnt_want_write(file->f_path.mnt); 1876 if (err) 1877 goto out; 1878 1879 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 1880 dentry = lookup_one_len(vol_args->name, parent, namelen); 1881 if (IS_ERR(dentry)) { 1882 err = PTR_ERR(dentry); 1883 goto out_unlock_dir; 1884 } 1885 1886 if (!dentry->d_inode) { 1887 err = -ENOENT; 1888 goto out_dput; 1889 } 1890 1891 inode = dentry->d_inode; 1892 dest = BTRFS_I(inode)->root; 1893 if (!capable(CAP_SYS_ADMIN)){ 1894 /* 1895 * Regular user. Only allow this with a special mount 1896 * option, when the user has write+exec access to the 1897 * subvol root, and when rmdir(2) would have been 1898 * allowed. 1899 * 1900 * Note that this is _not_ check that the subvol is 1901 * empty or doesn't contain data that we wouldn't 1902 * otherwise be able to delete. 1903 * 1904 * Users who want to delete empty subvols should try 1905 * rmdir(2). 1906 */ 1907 err = -EPERM; 1908 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 1909 goto out_dput; 1910 1911 /* 1912 * Do not allow deletion if the parent dir is the same 1913 * as the dir to be deleted. That means the ioctl 1914 * must be called on the dentry referencing the root 1915 * of the subvol, not a random directory contained 1916 * within it. 1917 */ 1918 err = -EINVAL; 1919 if (root == dest) 1920 goto out_dput; 1921 1922 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 1923 if (err) 1924 goto out_dput; 1925 1926 /* check if subvolume may be deleted by a non-root user */ 1927 err = btrfs_may_delete(dir, dentry, 1); 1928 if (err) 1929 goto out_dput; 1930 } 1931 1932 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 1933 err = -EINVAL; 1934 goto out_dput; 1935 } 1936 1937 mutex_lock(&inode->i_mutex); 1938 err = d_invalidate(dentry); 1939 if (err) 1940 goto out_unlock; 1941 1942 down_write(&root->fs_info->subvol_sem); 1943 1944 err = may_destroy_subvol(dest); 1945 if (err) 1946 goto out_up_write; 1947 1948 trans = btrfs_start_transaction(root, 0); 1949 if (IS_ERR(trans)) { 1950 err = PTR_ERR(trans); 1951 goto out_up_write; 1952 } 1953 trans->block_rsv = &root->fs_info->global_block_rsv; 1954 1955 ret = btrfs_unlink_subvol(trans, root, dir, 1956 dest->root_key.objectid, 1957 dentry->d_name.name, 1958 dentry->d_name.len); 1959 BUG_ON(ret); 1960 1961 btrfs_record_root_in_trans(trans, dest); 1962 1963 memset(&dest->root_item.drop_progress, 0, 1964 sizeof(dest->root_item.drop_progress)); 1965 dest->root_item.drop_level = 0; 1966 btrfs_set_root_refs(&dest->root_item, 0); 1967 1968 if (!xchg(&dest->orphan_item_inserted, 1)) { 1969 ret = btrfs_insert_orphan_item(trans, 1970 root->fs_info->tree_root, 1971 dest->root_key.objectid); 1972 BUG_ON(ret); 1973 } 1974 1975 ret = btrfs_end_transaction(trans, root); 1976 BUG_ON(ret); 1977 inode->i_flags |= S_DEAD; 1978 out_up_write: 1979 up_write(&root->fs_info->subvol_sem); 1980 out_unlock: 1981 mutex_unlock(&inode->i_mutex); 1982 if (!err) { 1983 shrink_dcache_sb(root->fs_info->sb); 1984 btrfs_invalidate_inodes(dest); 1985 d_delete(dentry); 1986 } 1987 out_dput: 1988 dput(dentry); 1989 out_unlock_dir: 1990 mutex_unlock(&dir->i_mutex); 1991 mnt_drop_write(file->f_path.mnt); 1992 out: 1993 kfree(vol_args); 1994 return err; 1995 } 1996 1997 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 1998 { 1999 struct inode *inode = fdentry(file)->d_inode; 2000 struct btrfs_root *root = BTRFS_I(inode)->root; 2001 struct btrfs_ioctl_defrag_range_args *range; 2002 int ret; 2003 2004 if (btrfs_root_readonly(root)) 2005 return -EROFS; 2006 2007 ret = mnt_want_write(file->f_path.mnt); 2008 if (ret) 2009 return ret; 2010 2011 switch (inode->i_mode & S_IFMT) { 2012 case S_IFDIR: 2013 if (!capable(CAP_SYS_ADMIN)) { 2014 ret = -EPERM; 2015 goto out; 2016 } 2017 ret = btrfs_defrag_root(root, 0); 2018 if (ret) 2019 goto out; 2020 ret = btrfs_defrag_root(root->fs_info->extent_root, 0); 2021 break; 2022 case S_IFREG: 2023 if (!(file->f_mode & FMODE_WRITE)) { 2024 ret = -EINVAL; 2025 goto out; 2026 } 2027 2028 range = kzalloc(sizeof(*range), GFP_KERNEL); 2029 if (!range) { 2030 ret = -ENOMEM; 2031 goto out; 2032 } 2033 2034 if (argp) { 2035 if (copy_from_user(range, argp, 2036 sizeof(*range))) { 2037 ret = -EFAULT; 2038 kfree(range); 2039 goto out; 2040 } 2041 /* compression requires us to start the IO */ 2042 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2043 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2044 range->extent_thresh = (u32)-1; 2045 } 2046 } else { 2047 /* the rest are all set to zero by kzalloc */ 2048 range->len = (u64)-1; 2049 } 2050 ret = btrfs_defrag_file(fdentry(file)->d_inode, file, 2051 range, 0, 0); 2052 if (ret > 0) 2053 ret = 0; 2054 kfree(range); 2055 break; 2056 default: 2057 ret = -EINVAL; 2058 } 2059 out: 2060 mnt_drop_write(file->f_path.mnt); 2061 return ret; 2062 } 2063 2064 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 2065 { 2066 struct btrfs_ioctl_vol_args *vol_args; 2067 int ret; 2068 2069 if (!capable(CAP_SYS_ADMIN)) 2070 return -EPERM; 2071 2072 mutex_lock(&root->fs_info->volume_mutex); 2073 if (root->fs_info->balance_ctl) { 2074 printk(KERN_INFO "btrfs: balance in progress\n"); 2075 ret = -EINVAL; 2076 goto out; 2077 } 2078 2079 vol_args = memdup_user(arg, sizeof(*vol_args)); 2080 if (IS_ERR(vol_args)) { 2081 ret = PTR_ERR(vol_args); 2082 goto out; 2083 } 2084 2085 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2086 ret = btrfs_init_new_device(root, vol_args->name); 2087 2088 kfree(vol_args); 2089 out: 2090 mutex_unlock(&root->fs_info->volume_mutex); 2091 return ret; 2092 } 2093 2094 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) 2095 { 2096 struct btrfs_ioctl_vol_args *vol_args; 2097 int ret; 2098 2099 if (!capable(CAP_SYS_ADMIN)) 2100 return -EPERM; 2101 2102 if (root->fs_info->sb->s_flags & MS_RDONLY) 2103 return -EROFS; 2104 2105 mutex_lock(&root->fs_info->volume_mutex); 2106 if (root->fs_info->balance_ctl) { 2107 printk(KERN_INFO "btrfs: balance in progress\n"); 2108 ret = -EINVAL; 2109 goto out; 2110 } 2111 2112 vol_args = memdup_user(arg, sizeof(*vol_args)); 2113 if (IS_ERR(vol_args)) { 2114 ret = PTR_ERR(vol_args); 2115 goto out; 2116 } 2117 2118 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2119 ret = btrfs_rm_device(root, vol_args->name); 2120 2121 kfree(vol_args); 2122 out: 2123 mutex_unlock(&root->fs_info->volume_mutex); 2124 return ret; 2125 } 2126 2127 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) 2128 { 2129 struct btrfs_ioctl_fs_info_args *fi_args; 2130 struct btrfs_device *device; 2131 struct btrfs_device *next; 2132 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2133 int ret = 0; 2134 2135 if (!capable(CAP_SYS_ADMIN)) 2136 return -EPERM; 2137 2138 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 2139 if (!fi_args) 2140 return -ENOMEM; 2141 2142 fi_args->num_devices = fs_devices->num_devices; 2143 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); 2144 2145 mutex_lock(&fs_devices->device_list_mutex); 2146 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 2147 if (device->devid > fi_args->max_id) 2148 fi_args->max_id = device->devid; 2149 } 2150 mutex_unlock(&fs_devices->device_list_mutex); 2151 2152 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 2153 ret = -EFAULT; 2154 2155 kfree(fi_args); 2156 return ret; 2157 } 2158 2159 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) 2160 { 2161 struct btrfs_ioctl_dev_info_args *di_args; 2162 struct btrfs_device *dev; 2163 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2164 int ret = 0; 2165 char *s_uuid = NULL; 2166 char empty_uuid[BTRFS_UUID_SIZE] = {0}; 2167 2168 if (!capable(CAP_SYS_ADMIN)) 2169 return -EPERM; 2170 2171 di_args = memdup_user(arg, sizeof(*di_args)); 2172 if (IS_ERR(di_args)) 2173 return PTR_ERR(di_args); 2174 2175 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0) 2176 s_uuid = di_args->uuid; 2177 2178 mutex_lock(&fs_devices->device_list_mutex); 2179 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL); 2180 mutex_unlock(&fs_devices->device_list_mutex); 2181 2182 if (!dev) { 2183 ret = -ENODEV; 2184 goto out; 2185 } 2186 2187 di_args->devid = dev->devid; 2188 di_args->bytes_used = dev->bytes_used; 2189 di_args->total_bytes = dev->total_bytes; 2190 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 2191 strncpy(di_args->path, dev->name, sizeof(di_args->path)); 2192 2193 out: 2194 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 2195 ret = -EFAULT; 2196 2197 kfree(di_args); 2198 return ret; 2199 } 2200 2201 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 2202 u64 off, u64 olen, u64 destoff) 2203 { 2204 struct inode *inode = fdentry(file)->d_inode; 2205 struct btrfs_root *root = BTRFS_I(inode)->root; 2206 struct file *src_file; 2207 struct inode *src; 2208 struct btrfs_trans_handle *trans; 2209 struct btrfs_path *path; 2210 struct extent_buffer *leaf; 2211 char *buf; 2212 struct btrfs_key key; 2213 u32 nritems; 2214 int slot; 2215 int ret; 2216 u64 len = olen; 2217 u64 bs = root->fs_info->sb->s_blocksize; 2218 u64 hint_byte; 2219 2220 /* 2221 * TODO: 2222 * - split compressed inline extents. annoying: we need to 2223 * decompress into destination's address_space (the file offset 2224 * may change, so source mapping won't do), then recompress (or 2225 * otherwise reinsert) a subrange. 2226 * - allow ranges within the same file to be cloned (provided 2227 * they don't overlap)? 2228 */ 2229 2230 /* the destination must be opened for writing */ 2231 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) 2232 return -EINVAL; 2233 2234 if (btrfs_root_readonly(root)) 2235 return -EROFS; 2236 2237 ret = mnt_want_write(file->f_path.mnt); 2238 if (ret) 2239 return ret; 2240 2241 src_file = fget(srcfd); 2242 if (!src_file) { 2243 ret = -EBADF; 2244 goto out_drop_write; 2245 } 2246 2247 src = src_file->f_dentry->d_inode; 2248 2249 ret = -EINVAL; 2250 if (src == inode) 2251 goto out_fput; 2252 2253 /* the src must be open for reading */ 2254 if (!(src_file->f_mode & FMODE_READ)) 2255 goto out_fput; 2256 2257 /* don't make the dst file partly checksummed */ 2258 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 2259 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) 2260 goto out_fput; 2261 2262 ret = -EISDIR; 2263 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 2264 goto out_fput; 2265 2266 ret = -EXDEV; 2267 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root) 2268 goto out_fput; 2269 2270 ret = -ENOMEM; 2271 buf = vmalloc(btrfs_level_size(root, 0)); 2272 if (!buf) 2273 goto out_fput; 2274 2275 path = btrfs_alloc_path(); 2276 if (!path) { 2277 vfree(buf); 2278 goto out_fput; 2279 } 2280 path->reada = 2; 2281 2282 if (inode < src) { 2283 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); 2284 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); 2285 } else { 2286 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); 2287 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); 2288 } 2289 2290 /* determine range to clone */ 2291 ret = -EINVAL; 2292 if (off + len > src->i_size || off + len < off) 2293 goto out_unlock; 2294 if (len == 0) 2295 olen = len = src->i_size - off; 2296 /* if we extend to eof, continue to block boundary */ 2297 if (off + len == src->i_size) 2298 len = ALIGN(src->i_size, bs) - off; 2299 2300 /* verify the end result is block aligned */ 2301 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || 2302 !IS_ALIGNED(destoff, bs)) 2303 goto out_unlock; 2304 2305 if (destoff > inode->i_size) { 2306 ret = btrfs_cont_expand(inode, inode->i_size, destoff); 2307 if (ret) 2308 goto out_unlock; 2309 } 2310 2311 /* truncate page cache pages from target inode range */ 2312 truncate_inode_pages_range(&inode->i_data, destoff, 2313 PAGE_CACHE_ALIGN(destoff + len) - 1); 2314 2315 /* do any pending delalloc/csum calc on src, one way or 2316 another, and lock file content */ 2317 while (1) { 2318 struct btrfs_ordered_extent *ordered; 2319 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2320 ordered = btrfs_lookup_first_ordered_extent(src, off+len); 2321 if (!ordered && 2322 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len, 2323 EXTENT_DELALLOC, 0, NULL)) 2324 break; 2325 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2326 if (ordered) 2327 btrfs_put_ordered_extent(ordered); 2328 btrfs_wait_ordered_range(src, off, len); 2329 } 2330 2331 /* clone data */ 2332 key.objectid = btrfs_ino(src); 2333 key.type = BTRFS_EXTENT_DATA_KEY; 2334 key.offset = 0; 2335 2336 while (1) { 2337 /* 2338 * note the key will change type as we walk through the 2339 * tree. 2340 */ 2341 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2342 if (ret < 0) 2343 goto out; 2344 2345 nritems = btrfs_header_nritems(path->nodes[0]); 2346 if (path->slots[0] >= nritems) { 2347 ret = btrfs_next_leaf(root, path); 2348 if (ret < 0) 2349 goto out; 2350 if (ret > 0) 2351 break; 2352 nritems = btrfs_header_nritems(path->nodes[0]); 2353 } 2354 leaf = path->nodes[0]; 2355 slot = path->slots[0]; 2356 2357 btrfs_item_key_to_cpu(leaf, &key, slot); 2358 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || 2359 key.objectid != btrfs_ino(src)) 2360 break; 2361 2362 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { 2363 struct btrfs_file_extent_item *extent; 2364 int type; 2365 u32 size; 2366 struct btrfs_key new_key; 2367 u64 disko = 0, diskl = 0; 2368 u64 datao = 0, datal = 0; 2369 u8 comp; 2370 u64 endoff; 2371 2372 size = btrfs_item_size_nr(leaf, slot); 2373 read_extent_buffer(leaf, buf, 2374 btrfs_item_ptr_offset(leaf, slot), 2375 size); 2376 2377 extent = btrfs_item_ptr(leaf, slot, 2378 struct btrfs_file_extent_item); 2379 comp = btrfs_file_extent_compression(leaf, extent); 2380 type = btrfs_file_extent_type(leaf, extent); 2381 if (type == BTRFS_FILE_EXTENT_REG || 2382 type == BTRFS_FILE_EXTENT_PREALLOC) { 2383 disko = btrfs_file_extent_disk_bytenr(leaf, 2384 extent); 2385 diskl = btrfs_file_extent_disk_num_bytes(leaf, 2386 extent); 2387 datao = btrfs_file_extent_offset(leaf, extent); 2388 datal = btrfs_file_extent_num_bytes(leaf, 2389 extent); 2390 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2391 /* take upper bound, may be compressed */ 2392 datal = btrfs_file_extent_ram_bytes(leaf, 2393 extent); 2394 } 2395 btrfs_release_path(path); 2396 2397 if (key.offset + datal <= off || 2398 key.offset >= off+len) 2399 goto next; 2400 2401 memcpy(&new_key, &key, sizeof(new_key)); 2402 new_key.objectid = btrfs_ino(inode); 2403 if (off <= key.offset) 2404 new_key.offset = key.offset + destoff - off; 2405 else 2406 new_key.offset = destoff; 2407 2408 /* 2409 * 1 - adjusting old extent (we may have to split it) 2410 * 1 - add new extent 2411 * 1 - inode update 2412 */ 2413 trans = btrfs_start_transaction(root, 3); 2414 if (IS_ERR(trans)) { 2415 ret = PTR_ERR(trans); 2416 goto out; 2417 } 2418 2419 if (type == BTRFS_FILE_EXTENT_REG || 2420 type == BTRFS_FILE_EXTENT_PREALLOC) { 2421 /* 2422 * a | --- range to clone ---| b 2423 * | ------------- extent ------------- | 2424 */ 2425 2426 /* substract range b */ 2427 if (key.offset + datal > off + len) 2428 datal = off + len - key.offset; 2429 2430 /* substract range a */ 2431 if (off > key.offset) { 2432 datao += off - key.offset; 2433 datal -= off - key.offset; 2434 } 2435 2436 ret = btrfs_drop_extents(trans, inode, 2437 new_key.offset, 2438 new_key.offset + datal, 2439 &hint_byte, 1); 2440 BUG_ON(ret); 2441 2442 ret = btrfs_insert_empty_item(trans, root, path, 2443 &new_key, size); 2444 BUG_ON(ret); 2445 2446 leaf = path->nodes[0]; 2447 slot = path->slots[0]; 2448 write_extent_buffer(leaf, buf, 2449 btrfs_item_ptr_offset(leaf, slot), 2450 size); 2451 2452 extent = btrfs_item_ptr(leaf, slot, 2453 struct btrfs_file_extent_item); 2454 2455 /* disko == 0 means it's a hole */ 2456 if (!disko) 2457 datao = 0; 2458 2459 btrfs_set_file_extent_offset(leaf, extent, 2460 datao); 2461 btrfs_set_file_extent_num_bytes(leaf, extent, 2462 datal); 2463 if (disko) { 2464 inode_add_bytes(inode, datal); 2465 ret = btrfs_inc_extent_ref(trans, root, 2466 disko, diskl, 0, 2467 root->root_key.objectid, 2468 btrfs_ino(inode), 2469 new_key.offset - datao, 2470 0); 2471 BUG_ON(ret); 2472 } 2473 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2474 u64 skip = 0; 2475 u64 trim = 0; 2476 if (off > key.offset) { 2477 skip = off - key.offset; 2478 new_key.offset += skip; 2479 } 2480 2481 if (key.offset + datal > off+len) 2482 trim = key.offset + datal - (off+len); 2483 2484 if (comp && (skip || trim)) { 2485 ret = -EINVAL; 2486 btrfs_end_transaction(trans, root); 2487 goto out; 2488 } 2489 size -= skip + trim; 2490 datal -= skip + trim; 2491 2492 ret = btrfs_drop_extents(trans, inode, 2493 new_key.offset, 2494 new_key.offset + datal, 2495 &hint_byte, 1); 2496 BUG_ON(ret); 2497 2498 ret = btrfs_insert_empty_item(trans, root, path, 2499 &new_key, size); 2500 BUG_ON(ret); 2501 2502 if (skip) { 2503 u32 start = 2504 btrfs_file_extent_calc_inline_size(0); 2505 memmove(buf+start, buf+start+skip, 2506 datal); 2507 } 2508 2509 leaf = path->nodes[0]; 2510 slot = path->slots[0]; 2511 write_extent_buffer(leaf, buf, 2512 btrfs_item_ptr_offset(leaf, slot), 2513 size); 2514 inode_add_bytes(inode, datal); 2515 } 2516 2517 btrfs_mark_buffer_dirty(leaf); 2518 btrfs_release_path(path); 2519 2520 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 2521 2522 /* 2523 * we round up to the block size at eof when 2524 * determining which extents to clone above, 2525 * but shouldn't round up the file size 2526 */ 2527 endoff = new_key.offset + datal; 2528 if (endoff > destoff+olen) 2529 endoff = destoff+olen; 2530 if (endoff > inode->i_size) 2531 btrfs_i_size_write(inode, endoff); 2532 2533 ret = btrfs_update_inode(trans, root, inode); 2534 BUG_ON(ret); 2535 btrfs_end_transaction(trans, root); 2536 } 2537 next: 2538 btrfs_release_path(path); 2539 key.offset++; 2540 } 2541 ret = 0; 2542 out: 2543 btrfs_release_path(path); 2544 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2545 out_unlock: 2546 mutex_unlock(&src->i_mutex); 2547 mutex_unlock(&inode->i_mutex); 2548 vfree(buf); 2549 btrfs_free_path(path); 2550 out_fput: 2551 fput(src_file); 2552 out_drop_write: 2553 mnt_drop_write(file->f_path.mnt); 2554 return ret; 2555 } 2556 2557 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) 2558 { 2559 struct btrfs_ioctl_clone_range_args args; 2560 2561 if (copy_from_user(&args, argp, sizeof(args))) 2562 return -EFAULT; 2563 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, 2564 args.src_length, args.dest_offset); 2565 } 2566 2567 /* 2568 * there are many ways the trans_start and trans_end ioctls can lead 2569 * to deadlocks. They should only be used by applications that 2570 * basically own the machine, and have a very in depth understanding 2571 * of all the possible deadlocks and enospc problems. 2572 */ 2573 static long btrfs_ioctl_trans_start(struct file *file) 2574 { 2575 struct inode *inode = fdentry(file)->d_inode; 2576 struct btrfs_root *root = BTRFS_I(inode)->root; 2577 struct btrfs_trans_handle *trans; 2578 int ret; 2579 2580 ret = -EPERM; 2581 if (!capable(CAP_SYS_ADMIN)) 2582 goto out; 2583 2584 ret = -EINPROGRESS; 2585 if (file->private_data) 2586 goto out; 2587 2588 ret = -EROFS; 2589 if (btrfs_root_readonly(root)) 2590 goto out; 2591 2592 ret = mnt_want_write(file->f_path.mnt); 2593 if (ret) 2594 goto out; 2595 2596 atomic_inc(&root->fs_info->open_ioctl_trans); 2597 2598 ret = -ENOMEM; 2599 trans = btrfs_start_ioctl_transaction(root); 2600 if (IS_ERR(trans)) 2601 goto out_drop; 2602 2603 file->private_data = trans; 2604 return 0; 2605 2606 out_drop: 2607 atomic_dec(&root->fs_info->open_ioctl_trans); 2608 mnt_drop_write(file->f_path.mnt); 2609 out: 2610 return ret; 2611 } 2612 2613 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) 2614 { 2615 struct inode *inode = fdentry(file)->d_inode; 2616 struct btrfs_root *root = BTRFS_I(inode)->root; 2617 struct btrfs_root *new_root; 2618 struct btrfs_dir_item *di; 2619 struct btrfs_trans_handle *trans; 2620 struct btrfs_path *path; 2621 struct btrfs_key location; 2622 struct btrfs_disk_key disk_key; 2623 struct btrfs_super_block *disk_super; 2624 u64 features; 2625 u64 objectid = 0; 2626 u64 dir_id; 2627 2628 if (!capable(CAP_SYS_ADMIN)) 2629 return -EPERM; 2630 2631 if (copy_from_user(&objectid, argp, sizeof(objectid))) 2632 return -EFAULT; 2633 2634 if (!objectid) 2635 objectid = root->root_key.objectid; 2636 2637 location.objectid = objectid; 2638 location.type = BTRFS_ROOT_ITEM_KEY; 2639 location.offset = (u64)-1; 2640 2641 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); 2642 if (IS_ERR(new_root)) 2643 return PTR_ERR(new_root); 2644 2645 if (btrfs_root_refs(&new_root->root_item) == 0) 2646 return -ENOENT; 2647 2648 path = btrfs_alloc_path(); 2649 if (!path) 2650 return -ENOMEM; 2651 path->leave_spinning = 1; 2652 2653 trans = btrfs_start_transaction(root, 1); 2654 if (IS_ERR(trans)) { 2655 btrfs_free_path(path); 2656 return PTR_ERR(trans); 2657 } 2658 2659 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 2660 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, 2661 dir_id, "default", 7, 1); 2662 if (IS_ERR_OR_NULL(di)) { 2663 btrfs_free_path(path); 2664 btrfs_end_transaction(trans, root); 2665 printk(KERN_ERR "Umm, you don't have the default dir item, " 2666 "this isn't going to work\n"); 2667 return -ENOENT; 2668 } 2669 2670 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); 2671 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); 2672 btrfs_mark_buffer_dirty(path->nodes[0]); 2673 btrfs_free_path(path); 2674 2675 disk_super = root->fs_info->super_copy; 2676 features = btrfs_super_incompat_flags(disk_super); 2677 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) { 2678 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL; 2679 btrfs_set_super_incompat_flags(disk_super, features); 2680 } 2681 btrfs_end_transaction(trans, root); 2682 2683 return 0; 2684 } 2685 2686 static void get_block_group_info(struct list_head *groups_list, 2687 struct btrfs_ioctl_space_info *space) 2688 { 2689 struct btrfs_block_group_cache *block_group; 2690 2691 space->total_bytes = 0; 2692 space->used_bytes = 0; 2693 space->flags = 0; 2694 list_for_each_entry(block_group, groups_list, list) { 2695 space->flags = block_group->flags; 2696 space->total_bytes += block_group->key.offset; 2697 space->used_bytes += 2698 btrfs_block_group_used(&block_group->item); 2699 } 2700 } 2701 2702 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) 2703 { 2704 struct btrfs_ioctl_space_args space_args; 2705 struct btrfs_ioctl_space_info space; 2706 struct btrfs_ioctl_space_info *dest; 2707 struct btrfs_ioctl_space_info *dest_orig; 2708 struct btrfs_ioctl_space_info __user *user_dest; 2709 struct btrfs_space_info *info; 2710 u64 types[] = {BTRFS_BLOCK_GROUP_DATA, 2711 BTRFS_BLOCK_GROUP_SYSTEM, 2712 BTRFS_BLOCK_GROUP_METADATA, 2713 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; 2714 int num_types = 4; 2715 int alloc_size; 2716 int ret = 0; 2717 u64 slot_count = 0; 2718 int i, c; 2719 2720 if (copy_from_user(&space_args, 2721 (struct btrfs_ioctl_space_args __user *)arg, 2722 sizeof(space_args))) 2723 return -EFAULT; 2724 2725 for (i = 0; i < num_types; i++) { 2726 struct btrfs_space_info *tmp; 2727 2728 info = NULL; 2729 rcu_read_lock(); 2730 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 2731 list) { 2732 if (tmp->flags == types[i]) { 2733 info = tmp; 2734 break; 2735 } 2736 } 2737 rcu_read_unlock(); 2738 2739 if (!info) 2740 continue; 2741 2742 down_read(&info->groups_sem); 2743 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 2744 if (!list_empty(&info->block_groups[c])) 2745 slot_count++; 2746 } 2747 up_read(&info->groups_sem); 2748 } 2749 2750 /* space_slots == 0 means they are asking for a count */ 2751 if (space_args.space_slots == 0) { 2752 space_args.total_spaces = slot_count; 2753 goto out; 2754 } 2755 2756 slot_count = min_t(u64, space_args.space_slots, slot_count); 2757 2758 alloc_size = sizeof(*dest) * slot_count; 2759 2760 /* we generally have at most 6 or so space infos, one for each raid 2761 * level. So, a whole page should be more than enough for everyone 2762 */ 2763 if (alloc_size > PAGE_CACHE_SIZE) 2764 return -ENOMEM; 2765 2766 space_args.total_spaces = 0; 2767 dest = kmalloc(alloc_size, GFP_NOFS); 2768 if (!dest) 2769 return -ENOMEM; 2770 dest_orig = dest; 2771 2772 /* now we have a buffer to copy into */ 2773 for (i = 0; i < num_types; i++) { 2774 struct btrfs_space_info *tmp; 2775 2776 if (!slot_count) 2777 break; 2778 2779 info = NULL; 2780 rcu_read_lock(); 2781 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 2782 list) { 2783 if (tmp->flags == types[i]) { 2784 info = tmp; 2785 break; 2786 } 2787 } 2788 rcu_read_unlock(); 2789 2790 if (!info) 2791 continue; 2792 down_read(&info->groups_sem); 2793 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 2794 if (!list_empty(&info->block_groups[c])) { 2795 get_block_group_info(&info->block_groups[c], 2796 &space); 2797 memcpy(dest, &space, sizeof(space)); 2798 dest++; 2799 space_args.total_spaces++; 2800 slot_count--; 2801 } 2802 if (!slot_count) 2803 break; 2804 } 2805 up_read(&info->groups_sem); 2806 } 2807 2808 user_dest = (struct btrfs_ioctl_space_info *) 2809 (arg + sizeof(struct btrfs_ioctl_space_args)); 2810 2811 if (copy_to_user(user_dest, dest_orig, alloc_size)) 2812 ret = -EFAULT; 2813 2814 kfree(dest_orig); 2815 out: 2816 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) 2817 ret = -EFAULT; 2818 2819 return ret; 2820 } 2821 2822 /* 2823 * there are many ways the trans_start and trans_end ioctls can lead 2824 * to deadlocks. They should only be used by applications that 2825 * basically own the machine, and have a very in depth understanding 2826 * of all the possible deadlocks and enospc problems. 2827 */ 2828 long btrfs_ioctl_trans_end(struct file *file) 2829 { 2830 struct inode *inode = fdentry(file)->d_inode; 2831 struct btrfs_root *root = BTRFS_I(inode)->root; 2832 struct btrfs_trans_handle *trans; 2833 2834 trans = file->private_data; 2835 if (!trans) 2836 return -EINVAL; 2837 file->private_data = NULL; 2838 2839 btrfs_end_transaction(trans, root); 2840 2841 atomic_dec(&root->fs_info->open_ioctl_trans); 2842 2843 mnt_drop_write(file->f_path.mnt); 2844 return 0; 2845 } 2846 2847 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp) 2848 { 2849 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 2850 struct btrfs_trans_handle *trans; 2851 u64 transid; 2852 int ret; 2853 2854 trans = btrfs_start_transaction(root, 0); 2855 if (IS_ERR(trans)) 2856 return PTR_ERR(trans); 2857 transid = trans->transid; 2858 ret = btrfs_commit_transaction_async(trans, root, 0); 2859 if (ret) { 2860 btrfs_end_transaction(trans, root); 2861 return ret; 2862 } 2863 2864 if (argp) 2865 if (copy_to_user(argp, &transid, sizeof(transid))) 2866 return -EFAULT; 2867 return 0; 2868 } 2869 2870 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp) 2871 { 2872 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 2873 u64 transid; 2874 2875 if (argp) { 2876 if (copy_from_user(&transid, argp, sizeof(transid))) 2877 return -EFAULT; 2878 } else { 2879 transid = 0; /* current trans */ 2880 } 2881 return btrfs_wait_for_commit(root, transid); 2882 } 2883 2884 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg) 2885 { 2886 int ret; 2887 struct btrfs_ioctl_scrub_args *sa; 2888 2889 if (!capable(CAP_SYS_ADMIN)) 2890 return -EPERM; 2891 2892 sa = memdup_user(arg, sizeof(*sa)); 2893 if (IS_ERR(sa)) 2894 return PTR_ERR(sa); 2895 2896 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end, 2897 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY); 2898 2899 if (copy_to_user(arg, sa, sizeof(*sa))) 2900 ret = -EFAULT; 2901 2902 kfree(sa); 2903 return ret; 2904 } 2905 2906 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg) 2907 { 2908 if (!capable(CAP_SYS_ADMIN)) 2909 return -EPERM; 2910 2911 return btrfs_scrub_cancel(root); 2912 } 2913 2914 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, 2915 void __user *arg) 2916 { 2917 struct btrfs_ioctl_scrub_args *sa; 2918 int ret; 2919 2920 if (!capable(CAP_SYS_ADMIN)) 2921 return -EPERM; 2922 2923 sa = memdup_user(arg, sizeof(*sa)); 2924 if (IS_ERR(sa)) 2925 return PTR_ERR(sa); 2926 2927 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress); 2928 2929 if (copy_to_user(arg, sa, sizeof(*sa))) 2930 ret = -EFAULT; 2931 2932 kfree(sa); 2933 return ret; 2934 } 2935 2936 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) 2937 { 2938 int ret = 0; 2939 int i; 2940 u64 rel_ptr; 2941 int size; 2942 struct btrfs_ioctl_ino_path_args *ipa = NULL; 2943 struct inode_fs_paths *ipath = NULL; 2944 struct btrfs_path *path; 2945 2946 if (!capable(CAP_SYS_ADMIN)) 2947 return -EPERM; 2948 2949 path = btrfs_alloc_path(); 2950 if (!path) { 2951 ret = -ENOMEM; 2952 goto out; 2953 } 2954 2955 ipa = memdup_user(arg, sizeof(*ipa)); 2956 if (IS_ERR(ipa)) { 2957 ret = PTR_ERR(ipa); 2958 ipa = NULL; 2959 goto out; 2960 } 2961 2962 size = min_t(u32, ipa->size, 4096); 2963 ipath = init_ipath(size, root, path); 2964 if (IS_ERR(ipath)) { 2965 ret = PTR_ERR(ipath); 2966 ipath = NULL; 2967 goto out; 2968 } 2969 2970 ret = paths_from_inode(ipa->inum, ipath); 2971 if (ret < 0) 2972 goto out; 2973 2974 for (i = 0; i < ipath->fspath->elem_cnt; ++i) { 2975 rel_ptr = ipath->fspath->val[i] - 2976 (u64)(unsigned long)ipath->fspath->val; 2977 ipath->fspath->val[i] = rel_ptr; 2978 } 2979 2980 ret = copy_to_user((void *)(unsigned long)ipa->fspath, 2981 (void *)(unsigned long)ipath->fspath, size); 2982 if (ret) { 2983 ret = -EFAULT; 2984 goto out; 2985 } 2986 2987 out: 2988 btrfs_free_path(path); 2989 free_ipath(ipath); 2990 kfree(ipa); 2991 2992 return ret; 2993 } 2994 2995 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) 2996 { 2997 struct btrfs_data_container *inodes = ctx; 2998 const size_t c = 3 * sizeof(u64); 2999 3000 if (inodes->bytes_left >= c) { 3001 inodes->bytes_left -= c; 3002 inodes->val[inodes->elem_cnt] = inum; 3003 inodes->val[inodes->elem_cnt + 1] = offset; 3004 inodes->val[inodes->elem_cnt + 2] = root; 3005 inodes->elem_cnt += 3; 3006 } else { 3007 inodes->bytes_missing += c - inodes->bytes_left; 3008 inodes->bytes_left = 0; 3009 inodes->elem_missed += 3; 3010 } 3011 3012 return 0; 3013 } 3014 3015 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 3016 void __user *arg) 3017 { 3018 int ret = 0; 3019 int size; 3020 u64 extent_item_pos; 3021 struct btrfs_ioctl_logical_ino_args *loi; 3022 struct btrfs_data_container *inodes = NULL; 3023 struct btrfs_path *path = NULL; 3024 struct btrfs_key key; 3025 3026 if (!capable(CAP_SYS_ADMIN)) 3027 return -EPERM; 3028 3029 loi = memdup_user(arg, sizeof(*loi)); 3030 if (IS_ERR(loi)) { 3031 ret = PTR_ERR(loi); 3032 loi = NULL; 3033 goto out; 3034 } 3035 3036 path = btrfs_alloc_path(); 3037 if (!path) { 3038 ret = -ENOMEM; 3039 goto out; 3040 } 3041 3042 size = min_t(u32, loi->size, 4096); 3043 inodes = init_data_container(size); 3044 if (IS_ERR(inodes)) { 3045 ret = PTR_ERR(inodes); 3046 inodes = NULL; 3047 goto out; 3048 } 3049 3050 ret = extent_from_logical(root->fs_info, loi->logical, path, &key); 3051 btrfs_release_path(path); 3052 3053 if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) 3054 ret = -ENOENT; 3055 if (ret < 0) 3056 goto out; 3057 3058 extent_item_pos = loi->logical - key.objectid; 3059 ret = iterate_extent_inodes(root->fs_info, path, key.objectid, 3060 extent_item_pos, build_ino_list, 3061 inodes); 3062 3063 if (ret < 0) 3064 goto out; 3065 3066 ret = copy_to_user((void *)(unsigned long)loi->inodes, 3067 (void *)(unsigned long)inodes, size); 3068 if (ret) 3069 ret = -EFAULT; 3070 3071 out: 3072 btrfs_free_path(path); 3073 kfree(inodes); 3074 kfree(loi); 3075 3076 return ret; 3077 } 3078 3079 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3080 struct btrfs_ioctl_balance_args *bargs) 3081 { 3082 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3083 3084 bargs->flags = bctl->flags; 3085 3086 if (atomic_read(&fs_info->balance_running)) 3087 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 3088 if (atomic_read(&fs_info->balance_pause_req)) 3089 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 3090 if (atomic_read(&fs_info->balance_cancel_req)) 3091 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 3092 3093 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 3094 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 3095 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 3096 3097 if (lock) { 3098 spin_lock(&fs_info->balance_lock); 3099 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3100 spin_unlock(&fs_info->balance_lock); 3101 } else { 3102 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3103 } 3104 } 3105 3106 static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg) 3107 { 3108 struct btrfs_fs_info *fs_info = root->fs_info; 3109 struct btrfs_ioctl_balance_args *bargs; 3110 struct btrfs_balance_control *bctl; 3111 int ret; 3112 3113 if (!capable(CAP_SYS_ADMIN)) 3114 return -EPERM; 3115 3116 if (fs_info->sb->s_flags & MS_RDONLY) 3117 return -EROFS; 3118 3119 mutex_lock(&fs_info->volume_mutex); 3120 mutex_lock(&fs_info->balance_mutex); 3121 3122 if (arg) { 3123 bargs = memdup_user(arg, sizeof(*bargs)); 3124 if (IS_ERR(bargs)) { 3125 ret = PTR_ERR(bargs); 3126 goto out; 3127 } 3128 3129 if (bargs->flags & BTRFS_BALANCE_RESUME) { 3130 if (!fs_info->balance_ctl) { 3131 ret = -ENOTCONN; 3132 goto out_bargs; 3133 } 3134 3135 bctl = fs_info->balance_ctl; 3136 spin_lock(&fs_info->balance_lock); 3137 bctl->flags |= BTRFS_BALANCE_RESUME; 3138 spin_unlock(&fs_info->balance_lock); 3139 3140 goto do_balance; 3141 } 3142 } else { 3143 bargs = NULL; 3144 } 3145 3146 if (fs_info->balance_ctl) { 3147 ret = -EINPROGRESS; 3148 goto out_bargs; 3149 } 3150 3151 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3152 if (!bctl) { 3153 ret = -ENOMEM; 3154 goto out_bargs; 3155 } 3156 3157 bctl->fs_info = fs_info; 3158 if (arg) { 3159 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 3160 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 3161 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 3162 3163 bctl->flags = bargs->flags; 3164 } else { 3165 /* balance everything - no filters */ 3166 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 3167 } 3168 3169 do_balance: 3170 ret = btrfs_balance(bctl, bargs); 3171 /* 3172 * bctl is freed in __cancel_balance or in free_fs_info if 3173 * restriper was paused all the way until unmount 3174 */ 3175 if (arg) { 3176 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3177 ret = -EFAULT; 3178 } 3179 3180 out_bargs: 3181 kfree(bargs); 3182 out: 3183 mutex_unlock(&fs_info->balance_mutex); 3184 mutex_unlock(&fs_info->volume_mutex); 3185 return ret; 3186 } 3187 3188 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) 3189 { 3190 if (!capable(CAP_SYS_ADMIN)) 3191 return -EPERM; 3192 3193 switch (cmd) { 3194 case BTRFS_BALANCE_CTL_PAUSE: 3195 return btrfs_pause_balance(root->fs_info); 3196 case BTRFS_BALANCE_CTL_CANCEL: 3197 return btrfs_cancel_balance(root->fs_info); 3198 } 3199 3200 return -EINVAL; 3201 } 3202 3203 static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 3204 void __user *arg) 3205 { 3206 struct btrfs_fs_info *fs_info = root->fs_info; 3207 struct btrfs_ioctl_balance_args *bargs; 3208 int ret = 0; 3209 3210 if (!capable(CAP_SYS_ADMIN)) 3211 return -EPERM; 3212 3213 mutex_lock(&fs_info->balance_mutex); 3214 if (!fs_info->balance_ctl) { 3215 ret = -ENOTCONN; 3216 goto out; 3217 } 3218 3219 bargs = kzalloc(sizeof(*bargs), GFP_NOFS); 3220 if (!bargs) { 3221 ret = -ENOMEM; 3222 goto out; 3223 } 3224 3225 update_ioctl_balance_args(fs_info, 1, bargs); 3226 3227 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3228 ret = -EFAULT; 3229 3230 kfree(bargs); 3231 out: 3232 mutex_unlock(&fs_info->balance_mutex); 3233 return ret; 3234 } 3235 3236 long btrfs_ioctl(struct file *file, unsigned int 3237 cmd, unsigned long arg) 3238 { 3239 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 3240 void __user *argp = (void __user *)arg; 3241 3242 switch (cmd) { 3243 case FS_IOC_GETFLAGS: 3244 return btrfs_ioctl_getflags(file, argp); 3245 case FS_IOC_SETFLAGS: 3246 return btrfs_ioctl_setflags(file, argp); 3247 case FS_IOC_GETVERSION: 3248 return btrfs_ioctl_getversion(file, argp); 3249 case FITRIM: 3250 return btrfs_ioctl_fitrim(file, argp); 3251 case BTRFS_IOC_SNAP_CREATE: 3252 return btrfs_ioctl_snap_create(file, argp, 0); 3253 case BTRFS_IOC_SNAP_CREATE_V2: 3254 return btrfs_ioctl_snap_create_v2(file, argp, 0); 3255 case BTRFS_IOC_SUBVOL_CREATE: 3256 return btrfs_ioctl_snap_create(file, argp, 1); 3257 case BTRFS_IOC_SNAP_DESTROY: 3258 return btrfs_ioctl_snap_destroy(file, argp); 3259 case BTRFS_IOC_SUBVOL_GETFLAGS: 3260 return btrfs_ioctl_subvol_getflags(file, argp); 3261 case BTRFS_IOC_SUBVOL_SETFLAGS: 3262 return btrfs_ioctl_subvol_setflags(file, argp); 3263 case BTRFS_IOC_DEFAULT_SUBVOL: 3264 return btrfs_ioctl_default_subvol(file, argp); 3265 case BTRFS_IOC_DEFRAG: 3266 return btrfs_ioctl_defrag(file, NULL); 3267 case BTRFS_IOC_DEFRAG_RANGE: 3268 return btrfs_ioctl_defrag(file, argp); 3269 case BTRFS_IOC_RESIZE: 3270 return btrfs_ioctl_resize(root, argp); 3271 case BTRFS_IOC_ADD_DEV: 3272 return btrfs_ioctl_add_dev(root, argp); 3273 case BTRFS_IOC_RM_DEV: 3274 return btrfs_ioctl_rm_dev(root, argp); 3275 case BTRFS_IOC_FS_INFO: 3276 return btrfs_ioctl_fs_info(root, argp); 3277 case BTRFS_IOC_DEV_INFO: 3278 return btrfs_ioctl_dev_info(root, argp); 3279 case BTRFS_IOC_BALANCE: 3280 return btrfs_ioctl_balance(root, NULL); 3281 case BTRFS_IOC_CLONE: 3282 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 3283 case BTRFS_IOC_CLONE_RANGE: 3284 return btrfs_ioctl_clone_range(file, argp); 3285 case BTRFS_IOC_TRANS_START: 3286 return btrfs_ioctl_trans_start(file); 3287 case BTRFS_IOC_TRANS_END: 3288 return btrfs_ioctl_trans_end(file); 3289 case BTRFS_IOC_TREE_SEARCH: 3290 return btrfs_ioctl_tree_search(file, argp); 3291 case BTRFS_IOC_INO_LOOKUP: 3292 return btrfs_ioctl_ino_lookup(file, argp); 3293 case BTRFS_IOC_INO_PATHS: 3294 return btrfs_ioctl_ino_to_path(root, argp); 3295 case BTRFS_IOC_LOGICAL_INO: 3296 return btrfs_ioctl_logical_to_ino(root, argp); 3297 case BTRFS_IOC_SPACE_INFO: 3298 return btrfs_ioctl_space_info(root, argp); 3299 case BTRFS_IOC_SYNC: 3300 btrfs_sync_fs(file->f_dentry->d_sb, 1); 3301 return 0; 3302 case BTRFS_IOC_START_SYNC: 3303 return btrfs_ioctl_start_sync(file, argp); 3304 case BTRFS_IOC_WAIT_SYNC: 3305 return btrfs_ioctl_wait_sync(file, argp); 3306 case BTRFS_IOC_SCRUB: 3307 return btrfs_ioctl_scrub(root, argp); 3308 case BTRFS_IOC_SCRUB_CANCEL: 3309 return btrfs_ioctl_scrub_cancel(root, argp); 3310 case BTRFS_IOC_SCRUB_PROGRESS: 3311 return btrfs_ioctl_scrub_progress(root, argp); 3312 case BTRFS_IOC_BALANCE_V2: 3313 return btrfs_ioctl_balance(root, argp); 3314 case BTRFS_IOC_BALANCE_CTL: 3315 return btrfs_ioctl_balance_ctl(root, arg); 3316 case BTRFS_IOC_BALANCE_PROGRESS: 3317 return btrfs_ioctl_balance_progress(root, argp); 3318 } 3319 3320 return -ENOTTY; 3321 } 3322