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 mutex_lock(&inode->i_mutex); 872 ret = btrfs_delalloc_reserve_space(inode, 873 num_pages << PAGE_CACHE_SHIFT); 874 mutex_unlock(&inode->i_mutex); 875 if (ret) 876 return ret; 877 again: 878 ret = 0; 879 i_done = 0; 880 881 /* step one, lock all the pages */ 882 for (i = 0; i < num_pages; i++) { 883 struct page *page; 884 page = find_or_create_page(inode->i_mapping, 885 start_index + i, mask); 886 if (!page) 887 break; 888 889 if (!PageUptodate(page)) { 890 btrfs_readpage(NULL, page); 891 lock_page(page); 892 if (!PageUptodate(page)) { 893 unlock_page(page); 894 page_cache_release(page); 895 ret = -EIO; 896 break; 897 } 898 } 899 isize = i_size_read(inode); 900 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 901 if (!isize || page->index > file_end || 902 page->mapping != inode->i_mapping) { 903 /* whoops, we blew past eof, skip this page */ 904 unlock_page(page); 905 page_cache_release(page); 906 break; 907 } 908 pages[i] = page; 909 i_done++; 910 } 911 if (!i_done || ret) 912 goto out; 913 914 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 915 goto out; 916 917 /* 918 * so now we have a nice long stream of locked 919 * and up to date pages, lets wait on them 920 */ 921 for (i = 0; i < i_done; i++) 922 wait_on_page_writeback(pages[i]); 923 924 page_start = page_offset(pages[0]); 925 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; 926 927 lock_extent_bits(&BTRFS_I(inode)->io_tree, 928 page_start, page_end - 1, 0, &cached_state, 929 GFP_NOFS); 930 ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1); 931 if (ordered && 932 ordered->file_offset + ordered->len > page_start && 933 ordered->file_offset < page_end) { 934 btrfs_put_ordered_extent(ordered); 935 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 936 page_start, page_end - 1, 937 &cached_state, GFP_NOFS); 938 for (i = 0; i < i_done; i++) { 939 unlock_page(pages[i]); 940 page_cache_release(pages[i]); 941 } 942 btrfs_wait_ordered_range(inode, page_start, 943 page_end - page_start); 944 goto again; 945 } 946 if (ordered) 947 btrfs_put_ordered_extent(ordered); 948 949 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 950 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 951 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state, 952 GFP_NOFS); 953 954 if (i_done != num_pages) { 955 spin_lock(&BTRFS_I(inode)->lock); 956 BTRFS_I(inode)->outstanding_extents++; 957 spin_unlock(&BTRFS_I(inode)->lock); 958 btrfs_delalloc_release_space(inode, 959 (num_pages - i_done) << PAGE_CACHE_SHIFT); 960 } 961 962 963 btrfs_set_extent_delalloc(inode, page_start, page_end - 1, 964 &cached_state); 965 966 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 967 page_start, page_end - 1, &cached_state, 968 GFP_NOFS); 969 970 for (i = 0; i < i_done; i++) { 971 clear_page_dirty_for_io(pages[i]); 972 ClearPageChecked(pages[i]); 973 set_page_extent_mapped(pages[i]); 974 set_page_dirty(pages[i]); 975 unlock_page(pages[i]); 976 page_cache_release(pages[i]); 977 } 978 return i_done; 979 out: 980 for (i = 0; i < i_done; i++) { 981 unlock_page(pages[i]); 982 page_cache_release(pages[i]); 983 } 984 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT); 985 return ret; 986 987 } 988 989 int btrfs_defrag_file(struct inode *inode, struct file *file, 990 struct btrfs_ioctl_defrag_range_args *range, 991 u64 newer_than, unsigned long max_to_defrag) 992 { 993 struct btrfs_root *root = BTRFS_I(inode)->root; 994 struct btrfs_super_block *disk_super; 995 struct file_ra_state *ra = NULL; 996 unsigned long last_index; 997 u64 isize = i_size_read(inode); 998 u64 features; 999 u64 last_len = 0; 1000 u64 skip = 0; 1001 u64 defrag_end = 0; 1002 u64 newer_off = range->start; 1003 unsigned long i; 1004 unsigned long ra_index = 0; 1005 int ret; 1006 int defrag_count = 0; 1007 int compress_type = BTRFS_COMPRESS_ZLIB; 1008 int extent_thresh = range->extent_thresh; 1009 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; 1010 int cluster = max_cluster; 1011 u64 new_align = ~((u64)128 * 1024 - 1); 1012 struct page **pages = NULL; 1013 1014 if (extent_thresh == 0) 1015 extent_thresh = 256 * 1024; 1016 1017 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1018 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1019 return -EINVAL; 1020 if (range->compress_type) 1021 compress_type = range->compress_type; 1022 } 1023 1024 if (isize == 0) 1025 return 0; 1026 1027 /* 1028 * if we were not given a file, allocate a readahead 1029 * context 1030 */ 1031 if (!file) { 1032 ra = kzalloc(sizeof(*ra), GFP_NOFS); 1033 if (!ra) 1034 return -ENOMEM; 1035 file_ra_state_init(ra, inode->i_mapping); 1036 } else { 1037 ra = &file->f_ra; 1038 } 1039 1040 pages = kmalloc(sizeof(struct page *) * max_cluster, 1041 GFP_NOFS); 1042 if (!pages) { 1043 ret = -ENOMEM; 1044 goto out_ra; 1045 } 1046 1047 /* find the last page to defrag */ 1048 if (range->start + range->len > range->start) { 1049 last_index = min_t(u64, isize - 1, 1050 range->start + range->len - 1) >> PAGE_CACHE_SHIFT; 1051 } else { 1052 last_index = (isize - 1) >> PAGE_CACHE_SHIFT; 1053 } 1054 1055 if (newer_than) { 1056 ret = find_new_extents(root, inode, newer_than, 1057 &newer_off, 64 * 1024); 1058 if (!ret) { 1059 range->start = newer_off; 1060 /* 1061 * we always align our defrag to help keep 1062 * the extents in the file evenly spaced 1063 */ 1064 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1065 } else 1066 goto out_ra; 1067 } else { 1068 i = range->start >> PAGE_CACHE_SHIFT; 1069 } 1070 if (!max_to_defrag) 1071 max_to_defrag = last_index; 1072 1073 /* 1074 * make writeback starts from i, so the defrag range can be 1075 * written sequentially. 1076 */ 1077 if (i < inode->i_mapping->writeback_index) 1078 inode->i_mapping->writeback_index = i; 1079 1080 while (i <= last_index && defrag_count < max_to_defrag && 1081 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> 1082 PAGE_CACHE_SHIFT)) { 1083 /* 1084 * make sure we stop running if someone unmounts 1085 * the FS 1086 */ 1087 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1088 break; 1089 1090 if (!newer_than && 1091 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, 1092 PAGE_CACHE_SIZE, 1093 extent_thresh, 1094 &last_len, &skip, 1095 &defrag_end)) { 1096 unsigned long next; 1097 /* 1098 * the should_defrag function tells us how much to skip 1099 * bump our counter by the suggested amount 1100 */ 1101 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 1102 i = max(i + 1, next); 1103 continue; 1104 } 1105 1106 if (!newer_than) { 1107 cluster = (PAGE_CACHE_ALIGN(defrag_end) >> 1108 PAGE_CACHE_SHIFT) - i; 1109 cluster = min(cluster, max_cluster); 1110 } else { 1111 cluster = max_cluster; 1112 } 1113 1114 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) 1115 BTRFS_I(inode)->force_compress = compress_type; 1116 1117 if (i + cluster > ra_index) { 1118 ra_index = max(i, ra_index); 1119 btrfs_force_ra(inode->i_mapping, ra, file, ra_index, 1120 cluster); 1121 ra_index += max_cluster; 1122 } 1123 1124 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1125 if (ret < 0) 1126 goto out_ra; 1127 1128 defrag_count += ret; 1129 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret); 1130 1131 if (newer_than) { 1132 if (newer_off == (u64)-1) 1133 break; 1134 1135 newer_off = max(newer_off + 1, 1136 (u64)i << PAGE_CACHE_SHIFT); 1137 1138 ret = find_new_extents(root, inode, 1139 newer_than, &newer_off, 1140 64 * 1024); 1141 if (!ret) { 1142 range->start = newer_off; 1143 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1144 } else { 1145 break; 1146 } 1147 } else { 1148 if (ret > 0) { 1149 i += ret; 1150 last_len += ret << PAGE_CACHE_SHIFT; 1151 } else { 1152 i++; 1153 last_len = 0; 1154 } 1155 } 1156 } 1157 1158 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) 1159 filemap_flush(inode->i_mapping); 1160 1161 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 1162 /* the filemap_flush will queue IO into the worker threads, but 1163 * we have to make sure the IO is actually started and that 1164 * ordered extents get created before we return 1165 */ 1166 atomic_inc(&root->fs_info->async_submit_draining); 1167 while (atomic_read(&root->fs_info->nr_async_submits) || 1168 atomic_read(&root->fs_info->async_delalloc_pages)) { 1169 wait_event(root->fs_info->async_submit_wait, 1170 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 1171 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 1172 } 1173 atomic_dec(&root->fs_info->async_submit_draining); 1174 1175 mutex_lock(&inode->i_mutex); 1176 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; 1177 mutex_unlock(&inode->i_mutex); 1178 } 1179 1180 disk_super = root->fs_info->super_copy; 1181 features = btrfs_super_incompat_flags(disk_super); 1182 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1183 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO; 1184 btrfs_set_super_incompat_flags(disk_super, features); 1185 } 1186 1187 ret = defrag_count; 1188 1189 out_ra: 1190 if (!file) 1191 kfree(ra); 1192 kfree(pages); 1193 return ret; 1194 } 1195 1196 static noinline int btrfs_ioctl_resize(struct btrfs_root *root, 1197 void __user *arg) 1198 { 1199 u64 new_size; 1200 u64 old_size; 1201 u64 devid = 1; 1202 struct btrfs_ioctl_vol_args *vol_args; 1203 struct btrfs_trans_handle *trans; 1204 struct btrfs_device *device = NULL; 1205 char *sizestr; 1206 char *devstr = NULL; 1207 int ret = 0; 1208 int mod = 0; 1209 1210 if (root->fs_info->sb->s_flags & MS_RDONLY) 1211 return -EROFS; 1212 1213 if (!capable(CAP_SYS_ADMIN)) 1214 return -EPERM; 1215 1216 mutex_lock(&root->fs_info->volume_mutex); 1217 if (root->fs_info->balance_ctl) { 1218 printk(KERN_INFO "btrfs: balance in progress\n"); 1219 ret = -EINVAL; 1220 goto out; 1221 } 1222 1223 vol_args = memdup_user(arg, sizeof(*vol_args)); 1224 if (IS_ERR(vol_args)) { 1225 ret = PTR_ERR(vol_args); 1226 goto out; 1227 } 1228 1229 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1230 1231 sizestr = vol_args->name; 1232 devstr = strchr(sizestr, ':'); 1233 if (devstr) { 1234 char *end; 1235 sizestr = devstr + 1; 1236 *devstr = '\0'; 1237 devstr = vol_args->name; 1238 devid = simple_strtoull(devstr, &end, 10); 1239 printk(KERN_INFO "btrfs: resizing devid %llu\n", 1240 (unsigned long long)devid); 1241 } 1242 device = btrfs_find_device(root, devid, NULL, NULL); 1243 if (!device) { 1244 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n", 1245 (unsigned long long)devid); 1246 ret = -EINVAL; 1247 goto out_free; 1248 } 1249 if (!strcmp(sizestr, "max")) 1250 new_size = device->bdev->bd_inode->i_size; 1251 else { 1252 if (sizestr[0] == '-') { 1253 mod = -1; 1254 sizestr++; 1255 } else if (sizestr[0] == '+') { 1256 mod = 1; 1257 sizestr++; 1258 } 1259 new_size = memparse(sizestr, NULL); 1260 if (new_size == 0) { 1261 ret = -EINVAL; 1262 goto out_free; 1263 } 1264 } 1265 1266 old_size = device->total_bytes; 1267 1268 if (mod < 0) { 1269 if (new_size > old_size) { 1270 ret = -EINVAL; 1271 goto out_free; 1272 } 1273 new_size = old_size - new_size; 1274 } else if (mod > 0) { 1275 new_size = old_size + new_size; 1276 } 1277 1278 if (new_size < 256 * 1024 * 1024) { 1279 ret = -EINVAL; 1280 goto out_free; 1281 } 1282 if (new_size > device->bdev->bd_inode->i_size) { 1283 ret = -EFBIG; 1284 goto out_free; 1285 } 1286 1287 do_div(new_size, root->sectorsize); 1288 new_size *= root->sectorsize; 1289 1290 printk(KERN_INFO "btrfs: new size for %s is %llu\n", 1291 device->name, (unsigned long long)new_size); 1292 1293 if (new_size > old_size) { 1294 trans = btrfs_start_transaction(root, 0); 1295 if (IS_ERR(trans)) { 1296 ret = PTR_ERR(trans); 1297 goto out_free; 1298 } 1299 ret = btrfs_grow_device(trans, device, new_size); 1300 btrfs_commit_transaction(trans, root); 1301 } else if (new_size < old_size) { 1302 ret = btrfs_shrink_device(device, new_size); 1303 } 1304 1305 out_free: 1306 kfree(vol_args); 1307 out: 1308 mutex_unlock(&root->fs_info->volume_mutex); 1309 return ret; 1310 } 1311 1312 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1313 char *name, 1314 unsigned long fd, 1315 int subvol, 1316 u64 *transid, 1317 bool readonly) 1318 { 1319 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 1320 struct file *src_file; 1321 int namelen; 1322 int ret = 0; 1323 1324 if (root->fs_info->sb->s_flags & MS_RDONLY) 1325 return -EROFS; 1326 1327 namelen = strlen(name); 1328 if (strchr(name, '/')) { 1329 ret = -EINVAL; 1330 goto out; 1331 } 1332 1333 if (subvol) { 1334 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1335 NULL, transid, readonly); 1336 } else { 1337 struct inode *src_inode; 1338 src_file = fget(fd); 1339 if (!src_file) { 1340 ret = -EINVAL; 1341 goto out; 1342 } 1343 1344 src_inode = src_file->f_path.dentry->d_inode; 1345 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { 1346 printk(KERN_INFO "btrfs: Snapshot src from " 1347 "another FS\n"); 1348 ret = -EINVAL; 1349 fput(src_file); 1350 goto out; 1351 } 1352 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1353 BTRFS_I(src_inode)->root, 1354 transid, readonly); 1355 fput(src_file); 1356 } 1357 out: 1358 return ret; 1359 } 1360 1361 static noinline int btrfs_ioctl_snap_create(struct file *file, 1362 void __user *arg, int subvol) 1363 { 1364 struct btrfs_ioctl_vol_args *vol_args; 1365 int ret; 1366 1367 vol_args = memdup_user(arg, sizeof(*vol_args)); 1368 if (IS_ERR(vol_args)) 1369 return PTR_ERR(vol_args); 1370 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1371 1372 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1373 vol_args->fd, subvol, 1374 NULL, false); 1375 1376 kfree(vol_args); 1377 return ret; 1378 } 1379 1380 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1381 void __user *arg, int subvol) 1382 { 1383 struct btrfs_ioctl_vol_args_v2 *vol_args; 1384 int ret; 1385 u64 transid = 0; 1386 u64 *ptr = NULL; 1387 bool readonly = false; 1388 1389 vol_args = memdup_user(arg, sizeof(*vol_args)); 1390 if (IS_ERR(vol_args)) 1391 return PTR_ERR(vol_args); 1392 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1393 1394 if (vol_args->flags & 1395 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) { 1396 ret = -EOPNOTSUPP; 1397 goto out; 1398 } 1399 1400 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1401 ptr = &transid; 1402 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1403 readonly = true; 1404 1405 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1406 vol_args->fd, subvol, 1407 ptr, readonly); 1408 1409 if (ret == 0 && ptr && 1410 copy_to_user(arg + 1411 offsetof(struct btrfs_ioctl_vol_args_v2, 1412 transid), ptr, sizeof(*ptr))) 1413 ret = -EFAULT; 1414 out: 1415 kfree(vol_args); 1416 return ret; 1417 } 1418 1419 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1420 void __user *arg) 1421 { 1422 struct inode *inode = fdentry(file)->d_inode; 1423 struct btrfs_root *root = BTRFS_I(inode)->root; 1424 int ret = 0; 1425 u64 flags = 0; 1426 1427 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1428 return -EINVAL; 1429 1430 down_read(&root->fs_info->subvol_sem); 1431 if (btrfs_root_readonly(root)) 1432 flags |= BTRFS_SUBVOL_RDONLY; 1433 up_read(&root->fs_info->subvol_sem); 1434 1435 if (copy_to_user(arg, &flags, sizeof(flags))) 1436 ret = -EFAULT; 1437 1438 return ret; 1439 } 1440 1441 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1442 void __user *arg) 1443 { 1444 struct inode *inode = fdentry(file)->d_inode; 1445 struct btrfs_root *root = BTRFS_I(inode)->root; 1446 struct btrfs_trans_handle *trans; 1447 u64 root_flags; 1448 u64 flags; 1449 int ret = 0; 1450 1451 if (root->fs_info->sb->s_flags & MS_RDONLY) 1452 return -EROFS; 1453 1454 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1455 return -EINVAL; 1456 1457 if (copy_from_user(&flags, arg, sizeof(flags))) 1458 return -EFAULT; 1459 1460 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) 1461 return -EINVAL; 1462 1463 if (flags & ~BTRFS_SUBVOL_RDONLY) 1464 return -EOPNOTSUPP; 1465 1466 if (!inode_owner_or_capable(inode)) 1467 return -EACCES; 1468 1469 down_write(&root->fs_info->subvol_sem); 1470 1471 /* nothing to do */ 1472 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1473 goto out; 1474 1475 root_flags = btrfs_root_flags(&root->root_item); 1476 if (flags & BTRFS_SUBVOL_RDONLY) 1477 btrfs_set_root_flags(&root->root_item, 1478 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1479 else 1480 btrfs_set_root_flags(&root->root_item, 1481 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1482 1483 trans = btrfs_start_transaction(root, 1); 1484 if (IS_ERR(trans)) { 1485 ret = PTR_ERR(trans); 1486 goto out_reset; 1487 } 1488 1489 ret = btrfs_update_root(trans, root->fs_info->tree_root, 1490 &root->root_key, &root->root_item); 1491 1492 btrfs_commit_transaction(trans, root); 1493 out_reset: 1494 if (ret) 1495 btrfs_set_root_flags(&root->root_item, root_flags); 1496 out: 1497 up_write(&root->fs_info->subvol_sem); 1498 return ret; 1499 } 1500 1501 /* 1502 * helper to check if the subvolume references other subvolumes 1503 */ 1504 static noinline int may_destroy_subvol(struct btrfs_root *root) 1505 { 1506 struct btrfs_path *path; 1507 struct btrfs_key key; 1508 int ret; 1509 1510 path = btrfs_alloc_path(); 1511 if (!path) 1512 return -ENOMEM; 1513 1514 key.objectid = root->root_key.objectid; 1515 key.type = BTRFS_ROOT_REF_KEY; 1516 key.offset = (u64)-1; 1517 1518 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, 1519 &key, path, 0, 0); 1520 if (ret < 0) 1521 goto out; 1522 BUG_ON(ret == 0); 1523 1524 ret = 0; 1525 if (path->slots[0] > 0) { 1526 path->slots[0]--; 1527 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 1528 if (key.objectid == root->root_key.objectid && 1529 key.type == BTRFS_ROOT_REF_KEY) 1530 ret = -ENOTEMPTY; 1531 } 1532 out: 1533 btrfs_free_path(path); 1534 return ret; 1535 } 1536 1537 static noinline int key_in_sk(struct btrfs_key *key, 1538 struct btrfs_ioctl_search_key *sk) 1539 { 1540 struct btrfs_key test; 1541 int ret; 1542 1543 test.objectid = sk->min_objectid; 1544 test.type = sk->min_type; 1545 test.offset = sk->min_offset; 1546 1547 ret = btrfs_comp_cpu_keys(key, &test); 1548 if (ret < 0) 1549 return 0; 1550 1551 test.objectid = sk->max_objectid; 1552 test.type = sk->max_type; 1553 test.offset = sk->max_offset; 1554 1555 ret = btrfs_comp_cpu_keys(key, &test); 1556 if (ret > 0) 1557 return 0; 1558 return 1; 1559 } 1560 1561 static noinline int copy_to_sk(struct btrfs_root *root, 1562 struct btrfs_path *path, 1563 struct btrfs_key *key, 1564 struct btrfs_ioctl_search_key *sk, 1565 char *buf, 1566 unsigned long *sk_offset, 1567 int *num_found) 1568 { 1569 u64 found_transid; 1570 struct extent_buffer *leaf; 1571 struct btrfs_ioctl_search_header sh; 1572 unsigned long item_off; 1573 unsigned long item_len; 1574 int nritems; 1575 int i; 1576 int slot; 1577 int ret = 0; 1578 1579 leaf = path->nodes[0]; 1580 slot = path->slots[0]; 1581 nritems = btrfs_header_nritems(leaf); 1582 1583 if (btrfs_header_generation(leaf) > sk->max_transid) { 1584 i = nritems; 1585 goto advance_key; 1586 } 1587 found_transid = btrfs_header_generation(leaf); 1588 1589 for (i = slot; i < nritems; i++) { 1590 item_off = btrfs_item_ptr_offset(leaf, i); 1591 item_len = btrfs_item_size_nr(leaf, i); 1592 1593 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) 1594 item_len = 0; 1595 1596 if (sizeof(sh) + item_len + *sk_offset > 1597 BTRFS_SEARCH_ARGS_BUFSIZE) { 1598 ret = 1; 1599 goto overflow; 1600 } 1601 1602 btrfs_item_key_to_cpu(leaf, key, i); 1603 if (!key_in_sk(key, sk)) 1604 continue; 1605 1606 sh.objectid = key->objectid; 1607 sh.offset = key->offset; 1608 sh.type = key->type; 1609 sh.len = item_len; 1610 sh.transid = found_transid; 1611 1612 /* copy search result header */ 1613 memcpy(buf + *sk_offset, &sh, sizeof(sh)); 1614 *sk_offset += sizeof(sh); 1615 1616 if (item_len) { 1617 char *p = buf + *sk_offset; 1618 /* copy the item */ 1619 read_extent_buffer(leaf, p, 1620 item_off, item_len); 1621 *sk_offset += item_len; 1622 } 1623 (*num_found)++; 1624 1625 if (*num_found >= sk->nr_items) 1626 break; 1627 } 1628 advance_key: 1629 ret = 0; 1630 if (key->offset < (u64)-1 && key->offset < sk->max_offset) 1631 key->offset++; 1632 else if (key->type < (u8)-1 && key->type < sk->max_type) { 1633 key->offset = 0; 1634 key->type++; 1635 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { 1636 key->offset = 0; 1637 key->type = 0; 1638 key->objectid++; 1639 } else 1640 ret = 1; 1641 overflow: 1642 return ret; 1643 } 1644 1645 static noinline int search_ioctl(struct inode *inode, 1646 struct btrfs_ioctl_search_args *args) 1647 { 1648 struct btrfs_root *root; 1649 struct btrfs_key key; 1650 struct btrfs_key max_key; 1651 struct btrfs_path *path; 1652 struct btrfs_ioctl_search_key *sk = &args->key; 1653 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; 1654 int ret; 1655 int num_found = 0; 1656 unsigned long sk_offset = 0; 1657 1658 path = btrfs_alloc_path(); 1659 if (!path) 1660 return -ENOMEM; 1661 1662 if (sk->tree_id == 0) { 1663 /* search the root of the inode that was passed */ 1664 root = BTRFS_I(inode)->root; 1665 } else { 1666 key.objectid = sk->tree_id; 1667 key.type = BTRFS_ROOT_ITEM_KEY; 1668 key.offset = (u64)-1; 1669 root = btrfs_read_fs_root_no_name(info, &key); 1670 if (IS_ERR(root)) { 1671 printk(KERN_ERR "could not find root %llu\n", 1672 sk->tree_id); 1673 btrfs_free_path(path); 1674 return -ENOENT; 1675 } 1676 } 1677 1678 key.objectid = sk->min_objectid; 1679 key.type = sk->min_type; 1680 key.offset = sk->min_offset; 1681 1682 max_key.objectid = sk->max_objectid; 1683 max_key.type = sk->max_type; 1684 max_key.offset = sk->max_offset; 1685 1686 path->keep_locks = 1; 1687 1688 while(1) { 1689 ret = btrfs_search_forward(root, &key, &max_key, path, 0, 1690 sk->min_transid); 1691 if (ret != 0) { 1692 if (ret > 0) 1693 ret = 0; 1694 goto err; 1695 } 1696 ret = copy_to_sk(root, path, &key, sk, args->buf, 1697 &sk_offset, &num_found); 1698 btrfs_release_path(path); 1699 if (ret || num_found >= sk->nr_items) 1700 break; 1701 1702 } 1703 ret = 0; 1704 err: 1705 sk->nr_items = num_found; 1706 btrfs_free_path(path); 1707 return ret; 1708 } 1709 1710 static noinline int btrfs_ioctl_tree_search(struct file *file, 1711 void __user *argp) 1712 { 1713 struct btrfs_ioctl_search_args *args; 1714 struct inode *inode; 1715 int ret; 1716 1717 if (!capable(CAP_SYS_ADMIN)) 1718 return -EPERM; 1719 1720 args = memdup_user(argp, sizeof(*args)); 1721 if (IS_ERR(args)) 1722 return PTR_ERR(args); 1723 1724 inode = fdentry(file)->d_inode; 1725 ret = search_ioctl(inode, args); 1726 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1727 ret = -EFAULT; 1728 kfree(args); 1729 return ret; 1730 } 1731 1732 /* 1733 * Search INODE_REFs to identify path name of 'dirid' directory 1734 * in a 'tree_id' tree. and sets path name to 'name'. 1735 */ 1736 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 1737 u64 tree_id, u64 dirid, char *name) 1738 { 1739 struct btrfs_root *root; 1740 struct btrfs_key key; 1741 char *ptr; 1742 int ret = -1; 1743 int slot; 1744 int len; 1745 int total_len = 0; 1746 struct btrfs_inode_ref *iref; 1747 struct extent_buffer *l; 1748 struct btrfs_path *path; 1749 1750 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 1751 name[0]='\0'; 1752 return 0; 1753 } 1754 1755 path = btrfs_alloc_path(); 1756 if (!path) 1757 return -ENOMEM; 1758 1759 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; 1760 1761 key.objectid = tree_id; 1762 key.type = BTRFS_ROOT_ITEM_KEY; 1763 key.offset = (u64)-1; 1764 root = btrfs_read_fs_root_no_name(info, &key); 1765 if (IS_ERR(root)) { 1766 printk(KERN_ERR "could not find root %llu\n", tree_id); 1767 ret = -ENOENT; 1768 goto out; 1769 } 1770 1771 key.objectid = dirid; 1772 key.type = BTRFS_INODE_REF_KEY; 1773 key.offset = (u64)-1; 1774 1775 while(1) { 1776 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1777 if (ret < 0) 1778 goto out; 1779 1780 l = path->nodes[0]; 1781 slot = path->slots[0]; 1782 if (ret > 0 && slot > 0) 1783 slot--; 1784 btrfs_item_key_to_cpu(l, &key, slot); 1785 1786 if (ret > 0 && (key.objectid != dirid || 1787 key.type != BTRFS_INODE_REF_KEY)) { 1788 ret = -ENOENT; 1789 goto out; 1790 } 1791 1792 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 1793 len = btrfs_inode_ref_name_len(l, iref); 1794 ptr -= len + 1; 1795 total_len += len + 1; 1796 if (ptr < name) 1797 goto out; 1798 1799 *(ptr + len) = '/'; 1800 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len); 1801 1802 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 1803 break; 1804 1805 btrfs_release_path(path); 1806 key.objectid = key.offset; 1807 key.offset = (u64)-1; 1808 dirid = key.objectid; 1809 } 1810 if (ptr < name) 1811 goto out; 1812 memmove(name, ptr, total_len); 1813 name[total_len]='\0'; 1814 ret = 0; 1815 out: 1816 btrfs_free_path(path); 1817 return ret; 1818 } 1819 1820 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 1821 void __user *argp) 1822 { 1823 struct btrfs_ioctl_ino_lookup_args *args; 1824 struct inode *inode; 1825 int ret; 1826 1827 if (!capable(CAP_SYS_ADMIN)) 1828 return -EPERM; 1829 1830 args = memdup_user(argp, sizeof(*args)); 1831 if (IS_ERR(args)) 1832 return PTR_ERR(args); 1833 1834 inode = fdentry(file)->d_inode; 1835 1836 if (args->treeid == 0) 1837 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 1838 1839 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 1840 args->treeid, args->objectid, 1841 args->name); 1842 1843 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1844 ret = -EFAULT; 1845 1846 kfree(args); 1847 return ret; 1848 } 1849 1850 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 1851 void __user *arg) 1852 { 1853 struct dentry *parent = fdentry(file); 1854 struct dentry *dentry; 1855 struct inode *dir = parent->d_inode; 1856 struct inode *inode; 1857 struct btrfs_root *root = BTRFS_I(dir)->root; 1858 struct btrfs_root *dest = NULL; 1859 struct btrfs_ioctl_vol_args *vol_args; 1860 struct btrfs_trans_handle *trans; 1861 int namelen; 1862 int ret; 1863 int err = 0; 1864 1865 vol_args = memdup_user(arg, sizeof(*vol_args)); 1866 if (IS_ERR(vol_args)) 1867 return PTR_ERR(vol_args); 1868 1869 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1870 namelen = strlen(vol_args->name); 1871 if (strchr(vol_args->name, '/') || 1872 strncmp(vol_args->name, "..", namelen) == 0) { 1873 err = -EINVAL; 1874 goto out; 1875 } 1876 1877 err = mnt_want_write(file->f_path.mnt); 1878 if (err) 1879 goto out; 1880 1881 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 1882 dentry = lookup_one_len(vol_args->name, parent, namelen); 1883 if (IS_ERR(dentry)) { 1884 err = PTR_ERR(dentry); 1885 goto out_unlock_dir; 1886 } 1887 1888 if (!dentry->d_inode) { 1889 err = -ENOENT; 1890 goto out_dput; 1891 } 1892 1893 inode = dentry->d_inode; 1894 dest = BTRFS_I(inode)->root; 1895 if (!capable(CAP_SYS_ADMIN)){ 1896 /* 1897 * Regular user. Only allow this with a special mount 1898 * option, when the user has write+exec access to the 1899 * subvol root, and when rmdir(2) would have been 1900 * allowed. 1901 * 1902 * Note that this is _not_ check that the subvol is 1903 * empty or doesn't contain data that we wouldn't 1904 * otherwise be able to delete. 1905 * 1906 * Users who want to delete empty subvols should try 1907 * rmdir(2). 1908 */ 1909 err = -EPERM; 1910 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 1911 goto out_dput; 1912 1913 /* 1914 * Do not allow deletion if the parent dir is the same 1915 * as the dir to be deleted. That means the ioctl 1916 * must be called on the dentry referencing the root 1917 * of the subvol, not a random directory contained 1918 * within it. 1919 */ 1920 err = -EINVAL; 1921 if (root == dest) 1922 goto out_dput; 1923 1924 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 1925 if (err) 1926 goto out_dput; 1927 1928 /* check if subvolume may be deleted by a non-root user */ 1929 err = btrfs_may_delete(dir, dentry, 1); 1930 if (err) 1931 goto out_dput; 1932 } 1933 1934 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 1935 err = -EINVAL; 1936 goto out_dput; 1937 } 1938 1939 mutex_lock(&inode->i_mutex); 1940 err = d_invalidate(dentry); 1941 if (err) 1942 goto out_unlock; 1943 1944 down_write(&root->fs_info->subvol_sem); 1945 1946 err = may_destroy_subvol(dest); 1947 if (err) 1948 goto out_up_write; 1949 1950 trans = btrfs_start_transaction(root, 0); 1951 if (IS_ERR(trans)) { 1952 err = PTR_ERR(trans); 1953 goto out_up_write; 1954 } 1955 trans->block_rsv = &root->fs_info->global_block_rsv; 1956 1957 ret = btrfs_unlink_subvol(trans, root, dir, 1958 dest->root_key.objectid, 1959 dentry->d_name.name, 1960 dentry->d_name.len); 1961 BUG_ON(ret); 1962 1963 btrfs_record_root_in_trans(trans, dest); 1964 1965 memset(&dest->root_item.drop_progress, 0, 1966 sizeof(dest->root_item.drop_progress)); 1967 dest->root_item.drop_level = 0; 1968 btrfs_set_root_refs(&dest->root_item, 0); 1969 1970 if (!xchg(&dest->orphan_item_inserted, 1)) { 1971 ret = btrfs_insert_orphan_item(trans, 1972 root->fs_info->tree_root, 1973 dest->root_key.objectid); 1974 BUG_ON(ret); 1975 } 1976 1977 ret = btrfs_end_transaction(trans, root); 1978 BUG_ON(ret); 1979 inode->i_flags |= S_DEAD; 1980 out_up_write: 1981 up_write(&root->fs_info->subvol_sem); 1982 out_unlock: 1983 mutex_unlock(&inode->i_mutex); 1984 if (!err) { 1985 shrink_dcache_sb(root->fs_info->sb); 1986 btrfs_invalidate_inodes(dest); 1987 d_delete(dentry); 1988 } 1989 out_dput: 1990 dput(dentry); 1991 out_unlock_dir: 1992 mutex_unlock(&dir->i_mutex); 1993 mnt_drop_write(file->f_path.mnt); 1994 out: 1995 kfree(vol_args); 1996 return err; 1997 } 1998 1999 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 2000 { 2001 struct inode *inode = fdentry(file)->d_inode; 2002 struct btrfs_root *root = BTRFS_I(inode)->root; 2003 struct btrfs_ioctl_defrag_range_args *range; 2004 int ret; 2005 2006 if (btrfs_root_readonly(root)) 2007 return -EROFS; 2008 2009 ret = mnt_want_write(file->f_path.mnt); 2010 if (ret) 2011 return ret; 2012 2013 switch (inode->i_mode & S_IFMT) { 2014 case S_IFDIR: 2015 if (!capable(CAP_SYS_ADMIN)) { 2016 ret = -EPERM; 2017 goto out; 2018 } 2019 ret = btrfs_defrag_root(root, 0); 2020 if (ret) 2021 goto out; 2022 ret = btrfs_defrag_root(root->fs_info->extent_root, 0); 2023 break; 2024 case S_IFREG: 2025 if (!(file->f_mode & FMODE_WRITE)) { 2026 ret = -EINVAL; 2027 goto out; 2028 } 2029 2030 range = kzalloc(sizeof(*range), GFP_KERNEL); 2031 if (!range) { 2032 ret = -ENOMEM; 2033 goto out; 2034 } 2035 2036 if (argp) { 2037 if (copy_from_user(range, argp, 2038 sizeof(*range))) { 2039 ret = -EFAULT; 2040 kfree(range); 2041 goto out; 2042 } 2043 /* compression requires us to start the IO */ 2044 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2045 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2046 range->extent_thresh = (u32)-1; 2047 } 2048 } else { 2049 /* the rest are all set to zero by kzalloc */ 2050 range->len = (u64)-1; 2051 } 2052 ret = btrfs_defrag_file(fdentry(file)->d_inode, file, 2053 range, 0, 0); 2054 if (ret > 0) 2055 ret = 0; 2056 kfree(range); 2057 break; 2058 default: 2059 ret = -EINVAL; 2060 } 2061 out: 2062 mnt_drop_write(file->f_path.mnt); 2063 return ret; 2064 } 2065 2066 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 2067 { 2068 struct btrfs_ioctl_vol_args *vol_args; 2069 int ret; 2070 2071 if (!capable(CAP_SYS_ADMIN)) 2072 return -EPERM; 2073 2074 mutex_lock(&root->fs_info->volume_mutex); 2075 if (root->fs_info->balance_ctl) { 2076 printk(KERN_INFO "btrfs: balance in progress\n"); 2077 ret = -EINVAL; 2078 goto out; 2079 } 2080 2081 vol_args = memdup_user(arg, sizeof(*vol_args)); 2082 if (IS_ERR(vol_args)) { 2083 ret = PTR_ERR(vol_args); 2084 goto out; 2085 } 2086 2087 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2088 ret = btrfs_init_new_device(root, vol_args->name); 2089 2090 kfree(vol_args); 2091 out: 2092 mutex_unlock(&root->fs_info->volume_mutex); 2093 return ret; 2094 } 2095 2096 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) 2097 { 2098 struct btrfs_ioctl_vol_args *vol_args; 2099 int ret; 2100 2101 if (!capable(CAP_SYS_ADMIN)) 2102 return -EPERM; 2103 2104 if (root->fs_info->sb->s_flags & MS_RDONLY) 2105 return -EROFS; 2106 2107 mutex_lock(&root->fs_info->volume_mutex); 2108 if (root->fs_info->balance_ctl) { 2109 printk(KERN_INFO "btrfs: balance in progress\n"); 2110 ret = -EINVAL; 2111 goto out; 2112 } 2113 2114 vol_args = memdup_user(arg, sizeof(*vol_args)); 2115 if (IS_ERR(vol_args)) { 2116 ret = PTR_ERR(vol_args); 2117 goto out; 2118 } 2119 2120 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2121 ret = btrfs_rm_device(root, vol_args->name); 2122 2123 kfree(vol_args); 2124 out: 2125 mutex_unlock(&root->fs_info->volume_mutex); 2126 return ret; 2127 } 2128 2129 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) 2130 { 2131 struct btrfs_ioctl_fs_info_args *fi_args; 2132 struct btrfs_device *device; 2133 struct btrfs_device *next; 2134 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2135 int ret = 0; 2136 2137 if (!capable(CAP_SYS_ADMIN)) 2138 return -EPERM; 2139 2140 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 2141 if (!fi_args) 2142 return -ENOMEM; 2143 2144 fi_args->num_devices = fs_devices->num_devices; 2145 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); 2146 2147 mutex_lock(&fs_devices->device_list_mutex); 2148 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 2149 if (device->devid > fi_args->max_id) 2150 fi_args->max_id = device->devid; 2151 } 2152 mutex_unlock(&fs_devices->device_list_mutex); 2153 2154 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 2155 ret = -EFAULT; 2156 2157 kfree(fi_args); 2158 return ret; 2159 } 2160 2161 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) 2162 { 2163 struct btrfs_ioctl_dev_info_args *di_args; 2164 struct btrfs_device *dev; 2165 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2166 int ret = 0; 2167 char *s_uuid = NULL; 2168 char empty_uuid[BTRFS_UUID_SIZE] = {0}; 2169 2170 if (!capable(CAP_SYS_ADMIN)) 2171 return -EPERM; 2172 2173 di_args = memdup_user(arg, sizeof(*di_args)); 2174 if (IS_ERR(di_args)) 2175 return PTR_ERR(di_args); 2176 2177 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0) 2178 s_uuid = di_args->uuid; 2179 2180 mutex_lock(&fs_devices->device_list_mutex); 2181 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL); 2182 mutex_unlock(&fs_devices->device_list_mutex); 2183 2184 if (!dev) { 2185 ret = -ENODEV; 2186 goto out; 2187 } 2188 2189 di_args->devid = dev->devid; 2190 di_args->bytes_used = dev->bytes_used; 2191 di_args->total_bytes = dev->total_bytes; 2192 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 2193 strncpy(di_args->path, dev->name, sizeof(di_args->path)); 2194 2195 out: 2196 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 2197 ret = -EFAULT; 2198 2199 kfree(di_args); 2200 return ret; 2201 } 2202 2203 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 2204 u64 off, u64 olen, u64 destoff) 2205 { 2206 struct inode *inode = fdentry(file)->d_inode; 2207 struct btrfs_root *root = BTRFS_I(inode)->root; 2208 struct file *src_file; 2209 struct inode *src; 2210 struct btrfs_trans_handle *trans; 2211 struct btrfs_path *path; 2212 struct extent_buffer *leaf; 2213 char *buf; 2214 struct btrfs_key key; 2215 u32 nritems; 2216 int slot; 2217 int ret; 2218 u64 len = olen; 2219 u64 bs = root->fs_info->sb->s_blocksize; 2220 u64 hint_byte; 2221 2222 /* 2223 * TODO: 2224 * - split compressed inline extents. annoying: we need to 2225 * decompress into destination's address_space (the file offset 2226 * may change, so source mapping won't do), then recompress (or 2227 * otherwise reinsert) a subrange. 2228 * - allow ranges within the same file to be cloned (provided 2229 * they don't overlap)? 2230 */ 2231 2232 /* the destination must be opened for writing */ 2233 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) 2234 return -EINVAL; 2235 2236 if (btrfs_root_readonly(root)) 2237 return -EROFS; 2238 2239 ret = mnt_want_write(file->f_path.mnt); 2240 if (ret) 2241 return ret; 2242 2243 src_file = fget(srcfd); 2244 if (!src_file) { 2245 ret = -EBADF; 2246 goto out_drop_write; 2247 } 2248 2249 src = src_file->f_dentry->d_inode; 2250 2251 ret = -EINVAL; 2252 if (src == inode) 2253 goto out_fput; 2254 2255 /* the src must be open for reading */ 2256 if (!(src_file->f_mode & FMODE_READ)) 2257 goto out_fput; 2258 2259 /* don't make the dst file partly checksummed */ 2260 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 2261 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) 2262 goto out_fput; 2263 2264 ret = -EISDIR; 2265 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 2266 goto out_fput; 2267 2268 ret = -EXDEV; 2269 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root) 2270 goto out_fput; 2271 2272 ret = -ENOMEM; 2273 buf = vmalloc(btrfs_level_size(root, 0)); 2274 if (!buf) 2275 goto out_fput; 2276 2277 path = btrfs_alloc_path(); 2278 if (!path) { 2279 vfree(buf); 2280 goto out_fput; 2281 } 2282 path->reada = 2; 2283 2284 if (inode < src) { 2285 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); 2286 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); 2287 } else { 2288 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); 2289 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); 2290 } 2291 2292 /* determine range to clone */ 2293 ret = -EINVAL; 2294 if (off + len > src->i_size || off + len < off) 2295 goto out_unlock; 2296 if (len == 0) 2297 olen = len = src->i_size - off; 2298 /* if we extend to eof, continue to block boundary */ 2299 if (off + len == src->i_size) 2300 len = ALIGN(src->i_size, bs) - off; 2301 2302 /* verify the end result is block aligned */ 2303 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || 2304 !IS_ALIGNED(destoff, bs)) 2305 goto out_unlock; 2306 2307 if (destoff > inode->i_size) { 2308 ret = btrfs_cont_expand(inode, inode->i_size, destoff); 2309 if (ret) 2310 goto out_unlock; 2311 } 2312 2313 /* truncate page cache pages from target inode range */ 2314 truncate_inode_pages_range(&inode->i_data, destoff, 2315 PAGE_CACHE_ALIGN(destoff + len) - 1); 2316 2317 /* do any pending delalloc/csum calc on src, one way or 2318 another, and lock file content */ 2319 while (1) { 2320 struct btrfs_ordered_extent *ordered; 2321 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2322 ordered = btrfs_lookup_first_ordered_extent(src, off+len); 2323 if (!ordered && 2324 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len, 2325 EXTENT_DELALLOC, 0, NULL)) 2326 break; 2327 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2328 if (ordered) 2329 btrfs_put_ordered_extent(ordered); 2330 btrfs_wait_ordered_range(src, off, len); 2331 } 2332 2333 /* clone data */ 2334 key.objectid = btrfs_ino(src); 2335 key.type = BTRFS_EXTENT_DATA_KEY; 2336 key.offset = 0; 2337 2338 while (1) { 2339 /* 2340 * note the key will change type as we walk through the 2341 * tree. 2342 */ 2343 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2344 if (ret < 0) 2345 goto out; 2346 2347 nritems = btrfs_header_nritems(path->nodes[0]); 2348 if (path->slots[0] >= nritems) { 2349 ret = btrfs_next_leaf(root, path); 2350 if (ret < 0) 2351 goto out; 2352 if (ret > 0) 2353 break; 2354 nritems = btrfs_header_nritems(path->nodes[0]); 2355 } 2356 leaf = path->nodes[0]; 2357 slot = path->slots[0]; 2358 2359 btrfs_item_key_to_cpu(leaf, &key, slot); 2360 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || 2361 key.objectid != btrfs_ino(src)) 2362 break; 2363 2364 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { 2365 struct btrfs_file_extent_item *extent; 2366 int type; 2367 u32 size; 2368 struct btrfs_key new_key; 2369 u64 disko = 0, diskl = 0; 2370 u64 datao = 0, datal = 0; 2371 u8 comp; 2372 u64 endoff; 2373 2374 size = btrfs_item_size_nr(leaf, slot); 2375 read_extent_buffer(leaf, buf, 2376 btrfs_item_ptr_offset(leaf, slot), 2377 size); 2378 2379 extent = btrfs_item_ptr(leaf, slot, 2380 struct btrfs_file_extent_item); 2381 comp = btrfs_file_extent_compression(leaf, extent); 2382 type = btrfs_file_extent_type(leaf, extent); 2383 if (type == BTRFS_FILE_EXTENT_REG || 2384 type == BTRFS_FILE_EXTENT_PREALLOC) { 2385 disko = btrfs_file_extent_disk_bytenr(leaf, 2386 extent); 2387 diskl = btrfs_file_extent_disk_num_bytes(leaf, 2388 extent); 2389 datao = btrfs_file_extent_offset(leaf, extent); 2390 datal = btrfs_file_extent_num_bytes(leaf, 2391 extent); 2392 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2393 /* take upper bound, may be compressed */ 2394 datal = btrfs_file_extent_ram_bytes(leaf, 2395 extent); 2396 } 2397 btrfs_release_path(path); 2398 2399 if (key.offset + datal <= off || 2400 key.offset >= off+len) 2401 goto next; 2402 2403 memcpy(&new_key, &key, sizeof(new_key)); 2404 new_key.objectid = btrfs_ino(inode); 2405 if (off <= key.offset) 2406 new_key.offset = key.offset + destoff - off; 2407 else 2408 new_key.offset = destoff; 2409 2410 /* 2411 * 1 - adjusting old extent (we may have to split it) 2412 * 1 - add new extent 2413 * 1 - inode update 2414 */ 2415 trans = btrfs_start_transaction(root, 3); 2416 if (IS_ERR(trans)) { 2417 ret = PTR_ERR(trans); 2418 goto out; 2419 } 2420 2421 if (type == BTRFS_FILE_EXTENT_REG || 2422 type == BTRFS_FILE_EXTENT_PREALLOC) { 2423 /* 2424 * a | --- range to clone ---| b 2425 * | ------------- extent ------------- | 2426 */ 2427 2428 /* substract range b */ 2429 if (key.offset + datal > off + len) 2430 datal = off + len - key.offset; 2431 2432 /* substract range a */ 2433 if (off > key.offset) { 2434 datao += off - key.offset; 2435 datal -= off - key.offset; 2436 } 2437 2438 ret = btrfs_drop_extents(trans, inode, 2439 new_key.offset, 2440 new_key.offset + datal, 2441 &hint_byte, 1); 2442 BUG_ON(ret); 2443 2444 ret = btrfs_insert_empty_item(trans, root, path, 2445 &new_key, size); 2446 BUG_ON(ret); 2447 2448 leaf = path->nodes[0]; 2449 slot = path->slots[0]; 2450 write_extent_buffer(leaf, buf, 2451 btrfs_item_ptr_offset(leaf, slot), 2452 size); 2453 2454 extent = btrfs_item_ptr(leaf, slot, 2455 struct btrfs_file_extent_item); 2456 2457 /* disko == 0 means it's a hole */ 2458 if (!disko) 2459 datao = 0; 2460 2461 btrfs_set_file_extent_offset(leaf, extent, 2462 datao); 2463 btrfs_set_file_extent_num_bytes(leaf, extent, 2464 datal); 2465 if (disko) { 2466 inode_add_bytes(inode, datal); 2467 ret = btrfs_inc_extent_ref(trans, root, 2468 disko, diskl, 0, 2469 root->root_key.objectid, 2470 btrfs_ino(inode), 2471 new_key.offset - datao, 2472 0); 2473 BUG_ON(ret); 2474 } 2475 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2476 u64 skip = 0; 2477 u64 trim = 0; 2478 if (off > key.offset) { 2479 skip = off - key.offset; 2480 new_key.offset += skip; 2481 } 2482 2483 if (key.offset + datal > off+len) 2484 trim = key.offset + datal - (off+len); 2485 2486 if (comp && (skip || trim)) { 2487 ret = -EINVAL; 2488 btrfs_end_transaction(trans, root); 2489 goto out; 2490 } 2491 size -= skip + trim; 2492 datal -= skip + trim; 2493 2494 ret = btrfs_drop_extents(trans, inode, 2495 new_key.offset, 2496 new_key.offset + datal, 2497 &hint_byte, 1); 2498 BUG_ON(ret); 2499 2500 ret = btrfs_insert_empty_item(trans, root, path, 2501 &new_key, size); 2502 BUG_ON(ret); 2503 2504 if (skip) { 2505 u32 start = 2506 btrfs_file_extent_calc_inline_size(0); 2507 memmove(buf+start, buf+start+skip, 2508 datal); 2509 } 2510 2511 leaf = path->nodes[0]; 2512 slot = path->slots[0]; 2513 write_extent_buffer(leaf, buf, 2514 btrfs_item_ptr_offset(leaf, slot), 2515 size); 2516 inode_add_bytes(inode, datal); 2517 } 2518 2519 btrfs_mark_buffer_dirty(leaf); 2520 btrfs_release_path(path); 2521 2522 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 2523 2524 /* 2525 * we round up to the block size at eof when 2526 * determining which extents to clone above, 2527 * but shouldn't round up the file size 2528 */ 2529 endoff = new_key.offset + datal; 2530 if (endoff > destoff+olen) 2531 endoff = destoff+olen; 2532 if (endoff > inode->i_size) 2533 btrfs_i_size_write(inode, endoff); 2534 2535 ret = btrfs_update_inode(trans, root, inode); 2536 BUG_ON(ret); 2537 btrfs_end_transaction(trans, root); 2538 } 2539 next: 2540 btrfs_release_path(path); 2541 key.offset++; 2542 } 2543 ret = 0; 2544 out: 2545 btrfs_release_path(path); 2546 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2547 out_unlock: 2548 mutex_unlock(&src->i_mutex); 2549 mutex_unlock(&inode->i_mutex); 2550 vfree(buf); 2551 btrfs_free_path(path); 2552 out_fput: 2553 fput(src_file); 2554 out_drop_write: 2555 mnt_drop_write(file->f_path.mnt); 2556 return ret; 2557 } 2558 2559 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) 2560 { 2561 struct btrfs_ioctl_clone_range_args args; 2562 2563 if (copy_from_user(&args, argp, sizeof(args))) 2564 return -EFAULT; 2565 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, 2566 args.src_length, args.dest_offset); 2567 } 2568 2569 /* 2570 * there are many ways the trans_start and trans_end ioctls can lead 2571 * to deadlocks. They should only be used by applications that 2572 * basically own the machine, and have a very in depth understanding 2573 * of all the possible deadlocks and enospc problems. 2574 */ 2575 static long btrfs_ioctl_trans_start(struct file *file) 2576 { 2577 struct inode *inode = fdentry(file)->d_inode; 2578 struct btrfs_root *root = BTRFS_I(inode)->root; 2579 struct btrfs_trans_handle *trans; 2580 int ret; 2581 2582 ret = -EPERM; 2583 if (!capable(CAP_SYS_ADMIN)) 2584 goto out; 2585 2586 ret = -EINPROGRESS; 2587 if (file->private_data) 2588 goto out; 2589 2590 ret = -EROFS; 2591 if (btrfs_root_readonly(root)) 2592 goto out; 2593 2594 ret = mnt_want_write(file->f_path.mnt); 2595 if (ret) 2596 goto out; 2597 2598 atomic_inc(&root->fs_info->open_ioctl_trans); 2599 2600 ret = -ENOMEM; 2601 trans = btrfs_start_ioctl_transaction(root); 2602 if (IS_ERR(trans)) 2603 goto out_drop; 2604 2605 file->private_data = trans; 2606 return 0; 2607 2608 out_drop: 2609 atomic_dec(&root->fs_info->open_ioctl_trans); 2610 mnt_drop_write(file->f_path.mnt); 2611 out: 2612 return ret; 2613 } 2614 2615 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) 2616 { 2617 struct inode *inode = fdentry(file)->d_inode; 2618 struct btrfs_root *root = BTRFS_I(inode)->root; 2619 struct btrfs_root *new_root; 2620 struct btrfs_dir_item *di; 2621 struct btrfs_trans_handle *trans; 2622 struct btrfs_path *path; 2623 struct btrfs_key location; 2624 struct btrfs_disk_key disk_key; 2625 struct btrfs_super_block *disk_super; 2626 u64 features; 2627 u64 objectid = 0; 2628 u64 dir_id; 2629 2630 if (!capable(CAP_SYS_ADMIN)) 2631 return -EPERM; 2632 2633 if (copy_from_user(&objectid, argp, sizeof(objectid))) 2634 return -EFAULT; 2635 2636 if (!objectid) 2637 objectid = root->root_key.objectid; 2638 2639 location.objectid = objectid; 2640 location.type = BTRFS_ROOT_ITEM_KEY; 2641 location.offset = (u64)-1; 2642 2643 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); 2644 if (IS_ERR(new_root)) 2645 return PTR_ERR(new_root); 2646 2647 if (btrfs_root_refs(&new_root->root_item) == 0) 2648 return -ENOENT; 2649 2650 path = btrfs_alloc_path(); 2651 if (!path) 2652 return -ENOMEM; 2653 path->leave_spinning = 1; 2654 2655 trans = btrfs_start_transaction(root, 1); 2656 if (IS_ERR(trans)) { 2657 btrfs_free_path(path); 2658 return PTR_ERR(trans); 2659 } 2660 2661 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 2662 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, 2663 dir_id, "default", 7, 1); 2664 if (IS_ERR_OR_NULL(di)) { 2665 btrfs_free_path(path); 2666 btrfs_end_transaction(trans, root); 2667 printk(KERN_ERR "Umm, you don't have the default dir item, " 2668 "this isn't going to work\n"); 2669 return -ENOENT; 2670 } 2671 2672 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); 2673 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); 2674 btrfs_mark_buffer_dirty(path->nodes[0]); 2675 btrfs_free_path(path); 2676 2677 disk_super = root->fs_info->super_copy; 2678 features = btrfs_super_incompat_flags(disk_super); 2679 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) { 2680 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL; 2681 btrfs_set_super_incompat_flags(disk_super, features); 2682 } 2683 btrfs_end_transaction(trans, root); 2684 2685 return 0; 2686 } 2687 2688 static void get_block_group_info(struct list_head *groups_list, 2689 struct btrfs_ioctl_space_info *space) 2690 { 2691 struct btrfs_block_group_cache *block_group; 2692 2693 space->total_bytes = 0; 2694 space->used_bytes = 0; 2695 space->flags = 0; 2696 list_for_each_entry(block_group, groups_list, list) { 2697 space->flags = block_group->flags; 2698 space->total_bytes += block_group->key.offset; 2699 space->used_bytes += 2700 btrfs_block_group_used(&block_group->item); 2701 } 2702 } 2703 2704 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) 2705 { 2706 struct btrfs_ioctl_space_args space_args; 2707 struct btrfs_ioctl_space_info space; 2708 struct btrfs_ioctl_space_info *dest; 2709 struct btrfs_ioctl_space_info *dest_orig; 2710 struct btrfs_ioctl_space_info __user *user_dest; 2711 struct btrfs_space_info *info; 2712 u64 types[] = {BTRFS_BLOCK_GROUP_DATA, 2713 BTRFS_BLOCK_GROUP_SYSTEM, 2714 BTRFS_BLOCK_GROUP_METADATA, 2715 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; 2716 int num_types = 4; 2717 int alloc_size; 2718 int ret = 0; 2719 u64 slot_count = 0; 2720 int i, c; 2721 2722 if (copy_from_user(&space_args, 2723 (struct btrfs_ioctl_space_args __user *)arg, 2724 sizeof(space_args))) 2725 return -EFAULT; 2726 2727 for (i = 0; i < num_types; i++) { 2728 struct btrfs_space_info *tmp; 2729 2730 info = NULL; 2731 rcu_read_lock(); 2732 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 2733 list) { 2734 if (tmp->flags == types[i]) { 2735 info = tmp; 2736 break; 2737 } 2738 } 2739 rcu_read_unlock(); 2740 2741 if (!info) 2742 continue; 2743 2744 down_read(&info->groups_sem); 2745 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 2746 if (!list_empty(&info->block_groups[c])) 2747 slot_count++; 2748 } 2749 up_read(&info->groups_sem); 2750 } 2751 2752 /* space_slots == 0 means they are asking for a count */ 2753 if (space_args.space_slots == 0) { 2754 space_args.total_spaces = slot_count; 2755 goto out; 2756 } 2757 2758 slot_count = min_t(u64, space_args.space_slots, slot_count); 2759 2760 alloc_size = sizeof(*dest) * slot_count; 2761 2762 /* we generally have at most 6 or so space infos, one for each raid 2763 * level. So, a whole page should be more than enough for everyone 2764 */ 2765 if (alloc_size > PAGE_CACHE_SIZE) 2766 return -ENOMEM; 2767 2768 space_args.total_spaces = 0; 2769 dest = kmalloc(alloc_size, GFP_NOFS); 2770 if (!dest) 2771 return -ENOMEM; 2772 dest_orig = dest; 2773 2774 /* now we have a buffer to copy into */ 2775 for (i = 0; i < num_types; i++) { 2776 struct btrfs_space_info *tmp; 2777 2778 if (!slot_count) 2779 break; 2780 2781 info = NULL; 2782 rcu_read_lock(); 2783 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 2784 list) { 2785 if (tmp->flags == types[i]) { 2786 info = tmp; 2787 break; 2788 } 2789 } 2790 rcu_read_unlock(); 2791 2792 if (!info) 2793 continue; 2794 down_read(&info->groups_sem); 2795 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 2796 if (!list_empty(&info->block_groups[c])) { 2797 get_block_group_info(&info->block_groups[c], 2798 &space); 2799 memcpy(dest, &space, sizeof(space)); 2800 dest++; 2801 space_args.total_spaces++; 2802 slot_count--; 2803 } 2804 if (!slot_count) 2805 break; 2806 } 2807 up_read(&info->groups_sem); 2808 } 2809 2810 user_dest = (struct btrfs_ioctl_space_info *) 2811 (arg + sizeof(struct btrfs_ioctl_space_args)); 2812 2813 if (copy_to_user(user_dest, dest_orig, alloc_size)) 2814 ret = -EFAULT; 2815 2816 kfree(dest_orig); 2817 out: 2818 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) 2819 ret = -EFAULT; 2820 2821 return ret; 2822 } 2823 2824 /* 2825 * there are many ways the trans_start and trans_end ioctls can lead 2826 * to deadlocks. They should only be used by applications that 2827 * basically own the machine, and have a very in depth understanding 2828 * of all the possible deadlocks and enospc problems. 2829 */ 2830 long btrfs_ioctl_trans_end(struct file *file) 2831 { 2832 struct inode *inode = fdentry(file)->d_inode; 2833 struct btrfs_root *root = BTRFS_I(inode)->root; 2834 struct btrfs_trans_handle *trans; 2835 2836 trans = file->private_data; 2837 if (!trans) 2838 return -EINVAL; 2839 file->private_data = NULL; 2840 2841 btrfs_end_transaction(trans, root); 2842 2843 atomic_dec(&root->fs_info->open_ioctl_trans); 2844 2845 mnt_drop_write(file->f_path.mnt); 2846 return 0; 2847 } 2848 2849 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp) 2850 { 2851 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 2852 struct btrfs_trans_handle *trans; 2853 u64 transid; 2854 int ret; 2855 2856 trans = btrfs_start_transaction(root, 0); 2857 if (IS_ERR(trans)) 2858 return PTR_ERR(trans); 2859 transid = trans->transid; 2860 ret = btrfs_commit_transaction_async(trans, root, 0); 2861 if (ret) { 2862 btrfs_end_transaction(trans, root); 2863 return ret; 2864 } 2865 2866 if (argp) 2867 if (copy_to_user(argp, &transid, sizeof(transid))) 2868 return -EFAULT; 2869 return 0; 2870 } 2871 2872 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp) 2873 { 2874 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 2875 u64 transid; 2876 2877 if (argp) { 2878 if (copy_from_user(&transid, argp, sizeof(transid))) 2879 return -EFAULT; 2880 } else { 2881 transid = 0; /* current trans */ 2882 } 2883 return btrfs_wait_for_commit(root, transid); 2884 } 2885 2886 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg) 2887 { 2888 int ret; 2889 struct btrfs_ioctl_scrub_args *sa; 2890 2891 if (!capable(CAP_SYS_ADMIN)) 2892 return -EPERM; 2893 2894 sa = memdup_user(arg, sizeof(*sa)); 2895 if (IS_ERR(sa)) 2896 return PTR_ERR(sa); 2897 2898 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end, 2899 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY); 2900 2901 if (copy_to_user(arg, sa, sizeof(*sa))) 2902 ret = -EFAULT; 2903 2904 kfree(sa); 2905 return ret; 2906 } 2907 2908 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg) 2909 { 2910 if (!capable(CAP_SYS_ADMIN)) 2911 return -EPERM; 2912 2913 return btrfs_scrub_cancel(root); 2914 } 2915 2916 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, 2917 void __user *arg) 2918 { 2919 struct btrfs_ioctl_scrub_args *sa; 2920 int ret; 2921 2922 if (!capable(CAP_SYS_ADMIN)) 2923 return -EPERM; 2924 2925 sa = memdup_user(arg, sizeof(*sa)); 2926 if (IS_ERR(sa)) 2927 return PTR_ERR(sa); 2928 2929 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress); 2930 2931 if (copy_to_user(arg, sa, sizeof(*sa))) 2932 ret = -EFAULT; 2933 2934 kfree(sa); 2935 return ret; 2936 } 2937 2938 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) 2939 { 2940 int ret = 0; 2941 int i; 2942 u64 rel_ptr; 2943 int size; 2944 struct btrfs_ioctl_ino_path_args *ipa = NULL; 2945 struct inode_fs_paths *ipath = NULL; 2946 struct btrfs_path *path; 2947 2948 if (!capable(CAP_SYS_ADMIN)) 2949 return -EPERM; 2950 2951 path = btrfs_alloc_path(); 2952 if (!path) { 2953 ret = -ENOMEM; 2954 goto out; 2955 } 2956 2957 ipa = memdup_user(arg, sizeof(*ipa)); 2958 if (IS_ERR(ipa)) { 2959 ret = PTR_ERR(ipa); 2960 ipa = NULL; 2961 goto out; 2962 } 2963 2964 size = min_t(u32, ipa->size, 4096); 2965 ipath = init_ipath(size, root, path); 2966 if (IS_ERR(ipath)) { 2967 ret = PTR_ERR(ipath); 2968 ipath = NULL; 2969 goto out; 2970 } 2971 2972 ret = paths_from_inode(ipa->inum, ipath); 2973 if (ret < 0) 2974 goto out; 2975 2976 for (i = 0; i < ipath->fspath->elem_cnt; ++i) { 2977 rel_ptr = ipath->fspath->val[i] - 2978 (u64)(unsigned long)ipath->fspath->val; 2979 ipath->fspath->val[i] = rel_ptr; 2980 } 2981 2982 ret = copy_to_user((void *)(unsigned long)ipa->fspath, 2983 (void *)(unsigned long)ipath->fspath, size); 2984 if (ret) { 2985 ret = -EFAULT; 2986 goto out; 2987 } 2988 2989 out: 2990 btrfs_free_path(path); 2991 free_ipath(ipath); 2992 kfree(ipa); 2993 2994 return ret; 2995 } 2996 2997 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) 2998 { 2999 struct btrfs_data_container *inodes = ctx; 3000 const size_t c = 3 * sizeof(u64); 3001 3002 if (inodes->bytes_left >= c) { 3003 inodes->bytes_left -= c; 3004 inodes->val[inodes->elem_cnt] = inum; 3005 inodes->val[inodes->elem_cnt + 1] = offset; 3006 inodes->val[inodes->elem_cnt + 2] = root; 3007 inodes->elem_cnt += 3; 3008 } else { 3009 inodes->bytes_missing += c - inodes->bytes_left; 3010 inodes->bytes_left = 0; 3011 inodes->elem_missed += 3; 3012 } 3013 3014 return 0; 3015 } 3016 3017 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 3018 void __user *arg) 3019 { 3020 int ret = 0; 3021 int size; 3022 u64 extent_item_pos; 3023 struct btrfs_ioctl_logical_ino_args *loi; 3024 struct btrfs_data_container *inodes = NULL; 3025 struct btrfs_path *path = NULL; 3026 struct btrfs_key key; 3027 3028 if (!capable(CAP_SYS_ADMIN)) 3029 return -EPERM; 3030 3031 loi = memdup_user(arg, sizeof(*loi)); 3032 if (IS_ERR(loi)) { 3033 ret = PTR_ERR(loi); 3034 loi = NULL; 3035 goto out; 3036 } 3037 3038 path = btrfs_alloc_path(); 3039 if (!path) { 3040 ret = -ENOMEM; 3041 goto out; 3042 } 3043 3044 size = min_t(u32, loi->size, 4096); 3045 inodes = init_data_container(size); 3046 if (IS_ERR(inodes)) { 3047 ret = PTR_ERR(inodes); 3048 inodes = NULL; 3049 goto out; 3050 } 3051 3052 ret = extent_from_logical(root->fs_info, loi->logical, path, &key); 3053 btrfs_release_path(path); 3054 3055 if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) 3056 ret = -ENOENT; 3057 if (ret < 0) 3058 goto out; 3059 3060 extent_item_pos = loi->logical - key.objectid; 3061 ret = iterate_extent_inodes(root->fs_info, path, key.objectid, 3062 extent_item_pos, build_ino_list, 3063 inodes); 3064 3065 if (ret < 0) 3066 goto out; 3067 3068 ret = copy_to_user((void *)(unsigned long)loi->inodes, 3069 (void *)(unsigned long)inodes, size); 3070 if (ret) 3071 ret = -EFAULT; 3072 3073 out: 3074 btrfs_free_path(path); 3075 kfree(inodes); 3076 kfree(loi); 3077 3078 return ret; 3079 } 3080 3081 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3082 struct btrfs_ioctl_balance_args *bargs) 3083 { 3084 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3085 3086 bargs->flags = bctl->flags; 3087 3088 if (atomic_read(&fs_info->balance_running)) 3089 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 3090 if (atomic_read(&fs_info->balance_pause_req)) 3091 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 3092 if (atomic_read(&fs_info->balance_cancel_req)) 3093 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 3094 3095 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 3096 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 3097 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 3098 3099 if (lock) { 3100 spin_lock(&fs_info->balance_lock); 3101 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3102 spin_unlock(&fs_info->balance_lock); 3103 } else { 3104 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3105 } 3106 } 3107 3108 static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg) 3109 { 3110 struct btrfs_fs_info *fs_info = root->fs_info; 3111 struct btrfs_ioctl_balance_args *bargs; 3112 struct btrfs_balance_control *bctl; 3113 int ret; 3114 3115 if (!capable(CAP_SYS_ADMIN)) 3116 return -EPERM; 3117 3118 if (fs_info->sb->s_flags & MS_RDONLY) 3119 return -EROFS; 3120 3121 mutex_lock(&fs_info->volume_mutex); 3122 mutex_lock(&fs_info->balance_mutex); 3123 3124 if (arg) { 3125 bargs = memdup_user(arg, sizeof(*bargs)); 3126 if (IS_ERR(bargs)) { 3127 ret = PTR_ERR(bargs); 3128 goto out; 3129 } 3130 3131 if (bargs->flags & BTRFS_BALANCE_RESUME) { 3132 if (!fs_info->balance_ctl) { 3133 ret = -ENOTCONN; 3134 goto out_bargs; 3135 } 3136 3137 bctl = fs_info->balance_ctl; 3138 spin_lock(&fs_info->balance_lock); 3139 bctl->flags |= BTRFS_BALANCE_RESUME; 3140 spin_unlock(&fs_info->balance_lock); 3141 3142 goto do_balance; 3143 } 3144 } else { 3145 bargs = NULL; 3146 } 3147 3148 if (fs_info->balance_ctl) { 3149 ret = -EINPROGRESS; 3150 goto out_bargs; 3151 } 3152 3153 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3154 if (!bctl) { 3155 ret = -ENOMEM; 3156 goto out_bargs; 3157 } 3158 3159 bctl->fs_info = fs_info; 3160 if (arg) { 3161 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 3162 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 3163 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 3164 3165 bctl->flags = bargs->flags; 3166 } else { 3167 /* balance everything - no filters */ 3168 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 3169 } 3170 3171 do_balance: 3172 ret = btrfs_balance(bctl, bargs); 3173 /* 3174 * bctl is freed in __cancel_balance or in free_fs_info if 3175 * restriper was paused all the way until unmount 3176 */ 3177 if (arg) { 3178 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3179 ret = -EFAULT; 3180 } 3181 3182 out_bargs: 3183 kfree(bargs); 3184 out: 3185 mutex_unlock(&fs_info->balance_mutex); 3186 mutex_unlock(&fs_info->volume_mutex); 3187 return ret; 3188 } 3189 3190 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) 3191 { 3192 if (!capable(CAP_SYS_ADMIN)) 3193 return -EPERM; 3194 3195 switch (cmd) { 3196 case BTRFS_BALANCE_CTL_PAUSE: 3197 return btrfs_pause_balance(root->fs_info); 3198 case BTRFS_BALANCE_CTL_CANCEL: 3199 return btrfs_cancel_balance(root->fs_info); 3200 } 3201 3202 return -EINVAL; 3203 } 3204 3205 static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 3206 void __user *arg) 3207 { 3208 struct btrfs_fs_info *fs_info = root->fs_info; 3209 struct btrfs_ioctl_balance_args *bargs; 3210 int ret = 0; 3211 3212 if (!capable(CAP_SYS_ADMIN)) 3213 return -EPERM; 3214 3215 mutex_lock(&fs_info->balance_mutex); 3216 if (!fs_info->balance_ctl) { 3217 ret = -ENOTCONN; 3218 goto out; 3219 } 3220 3221 bargs = kzalloc(sizeof(*bargs), GFP_NOFS); 3222 if (!bargs) { 3223 ret = -ENOMEM; 3224 goto out; 3225 } 3226 3227 update_ioctl_balance_args(fs_info, 1, bargs); 3228 3229 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3230 ret = -EFAULT; 3231 3232 kfree(bargs); 3233 out: 3234 mutex_unlock(&fs_info->balance_mutex); 3235 return ret; 3236 } 3237 3238 long btrfs_ioctl(struct file *file, unsigned int 3239 cmd, unsigned long arg) 3240 { 3241 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 3242 void __user *argp = (void __user *)arg; 3243 3244 switch (cmd) { 3245 case FS_IOC_GETFLAGS: 3246 return btrfs_ioctl_getflags(file, argp); 3247 case FS_IOC_SETFLAGS: 3248 return btrfs_ioctl_setflags(file, argp); 3249 case FS_IOC_GETVERSION: 3250 return btrfs_ioctl_getversion(file, argp); 3251 case FITRIM: 3252 return btrfs_ioctl_fitrim(file, argp); 3253 case BTRFS_IOC_SNAP_CREATE: 3254 return btrfs_ioctl_snap_create(file, argp, 0); 3255 case BTRFS_IOC_SNAP_CREATE_V2: 3256 return btrfs_ioctl_snap_create_v2(file, argp, 0); 3257 case BTRFS_IOC_SUBVOL_CREATE: 3258 return btrfs_ioctl_snap_create(file, argp, 1); 3259 case BTRFS_IOC_SNAP_DESTROY: 3260 return btrfs_ioctl_snap_destroy(file, argp); 3261 case BTRFS_IOC_SUBVOL_GETFLAGS: 3262 return btrfs_ioctl_subvol_getflags(file, argp); 3263 case BTRFS_IOC_SUBVOL_SETFLAGS: 3264 return btrfs_ioctl_subvol_setflags(file, argp); 3265 case BTRFS_IOC_DEFAULT_SUBVOL: 3266 return btrfs_ioctl_default_subvol(file, argp); 3267 case BTRFS_IOC_DEFRAG: 3268 return btrfs_ioctl_defrag(file, NULL); 3269 case BTRFS_IOC_DEFRAG_RANGE: 3270 return btrfs_ioctl_defrag(file, argp); 3271 case BTRFS_IOC_RESIZE: 3272 return btrfs_ioctl_resize(root, argp); 3273 case BTRFS_IOC_ADD_DEV: 3274 return btrfs_ioctl_add_dev(root, argp); 3275 case BTRFS_IOC_RM_DEV: 3276 return btrfs_ioctl_rm_dev(root, argp); 3277 case BTRFS_IOC_FS_INFO: 3278 return btrfs_ioctl_fs_info(root, argp); 3279 case BTRFS_IOC_DEV_INFO: 3280 return btrfs_ioctl_dev_info(root, argp); 3281 case BTRFS_IOC_BALANCE: 3282 return btrfs_ioctl_balance(root, NULL); 3283 case BTRFS_IOC_CLONE: 3284 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 3285 case BTRFS_IOC_CLONE_RANGE: 3286 return btrfs_ioctl_clone_range(file, argp); 3287 case BTRFS_IOC_TRANS_START: 3288 return btrfs_ioctl_trans_start(file); 3289 case BTRFS_IOC_TRANS_END: 3290 return btrfs_ioctl_trans_end(file); 3291 case BTRFS_IOC_TREE_SEARCH: 3292 return btrfs_ioctl_tree_search(file, argp); 3293 case BTRFS_IOC_INO_LOOKUP: 3294 return btrfs_ioctl_ino_lookup(file, argp); 3295 case BTRFS_IOC_INO_PATHS: 3296 return btrfs_ioctl_ino_to_path(root, argp); 3297 case BTRFS_IOC_LOGICAL_INO: 3298 return btrfs_ioctl_logical_to_ino(root, argp); 3299 case BTRFS_IOC_SPACE_INFO: 3300 return btrfs_ioctl_space_info(root, argp); 3301 case BTRFS_IOC_SYNC: 3302 btrfs_sync_fs(file->f_dentry->d_sb, 1); 3303 return 0; 3304 case BTRFS_IOC_START_SYNC: 3305 return btrfs_ioctl_start_sync(file, argp); 3306 case BTRFS_IOC_WAIT_SYNC: 3307 return btrfs_ioctl_wait_sync(file, argp); 3308 case BTRFS_IOC_SCRUB: 3309 return btrfs_ioctl_scrub(root, argp); 3310 case BTRFS_IOC_SCRUB_CANCEL: 3311 return btrfs_ioctl_scrub_cancel(root, argp); 3312 case BTRFS_IOC_SCRUB_PROGRESS: 3313 return btrfs_ioctl_scrub_progress(root, argp); 3314 case BTRFS_IOC_BALANCE_V2: 3315 return btrfs_ioctl_balance(root, argp); 3316 case BTRFS_IOC_BALANCE_CTL: 3317 return btrfs_ioctl_balance_ctl(root, arg); 3318 case BTRFS_IOC_BALANCE_PROGRESS: 3319 return btrfs_ioctl_balance_progress(root, argp); 3320 } 3321 3322 return -ENOTTY; 3323 } 3324