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