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 struct extent_io_tree *tree; 865 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 866 867 if (isize == 0) 868 return 0; 869 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 870 871 ret = btrfs_delalloc_reserve_space(inode, 872 num_pages << PAGE_CACHE_SHIFT); 873 if (ret) 874 return ret; 875 i_done = 0; 876 tree = &BTRFS_I(inode)->io_tree; 877 878 /* step one, lock all the pages */ 879 for (i = 0; i < num_pages; i++) { 880 struct page *page; 881 again: 882 page = find_or_create_page(inode->i_mapping, 883 start_index + i, mask); 884 if (!page) 885 break; 886 887 page_start = page_offset(page); 888 page_end = page_start + PAGE_CACHE_SIZE - 1; 889 while (1) { 890 lock_extent(tree, page_start, page_end, GFP_NOFS); 891 ordered = btrfs_lookup_ordered_extent(inode, 892 page_start); 893 unlock_extent(tree, page_start, page_end, GFP_NOFS); 894 if (!ordered) 895 break; 896 897 unlock_page(page); 898 btrfs_start_ordered_extent(inode, ordered, 1); 899 btrfs_put_ordered_extent(ordered); 900 lock_page(page); 901 } 902 903 if (!PageUptodate(page)) { 904 btrfs_readpage(NULL, page); 905 lock_page(page); 906 if (!PageUptodate(page)) { 907 unlock_page(page); 908 page_cache_release(page); 909 ret = -EIO; 910 break; 911 } 912 } 913 914 isize = i_size_read(inode); 915 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 916 if (!isize || page->index > file_end) { 917 /* whoops, we blew past eof, skip this page */ 918 unlock_page(page); 919 page_cache_release(page); 920 break; 921 } 922 923 if (page->mapping != inode->i_mapping) { 924 unlock_page(page); 925 page_cache_release(page); 926 goto again; 927 } 928 929 pages[i] = page; 930 i_done++; 931 } 932 if (!i_done || ret) 933 goto out; 934 935 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 936 goto out; 937 938 /* 939 * so now we have a nice long stream of locked 940 * and up to date pages, lets wait on them 941 */ 942 for (i = 0; i < i_done; i++) 943 wait_on_page_writeback(pages[i]); 944 945 page_start = page_offset(pages[0]); 946 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; 947 948 lock_extent_bits(&BTRFS_I(inode)->io_tree, 949 page_start, page_end - 1, 0, &cached_state, 950 GFP_NOFS); 951 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 952 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 953 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state, 954 GFP_NOFS); 955 956 if (i_done != num_pages) { 957 spin_lock(&BTRFS_I(inode)->lock); 958 BTRFS_I(inode)->outstanding_extents++; 959 spin_unlock(&BTRFS_I(inode)->lock); 960 btrfs_delalloc_release_space(inode, 961 (num_pages - i_done) << PAGE_CACHE_SHIFT); 962 } 963 964 965 btrfs_set_extent_delalloc(inode, page_start, page_end - 1, 966 &cached_state); 967 968 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 969 page_start, page_end - 1, &cached_state, 970 GFP_NOFS); 971 972 for (i = 0; i < i_done; i++) { 973 clear_page_dirty_for_io(pages[i]); 974 ClearPageChecked(pages[i]); 975 set_page_extent_mapped(pages[i]); 976 set_page_dirty(pages[i]); 977 unlock_page(pages[i]); 978 page_cache_release(pages[i]); 979 } 980 return i_done; 981 out: 982 for (i = 0; i < i_done; i++) { 983 unlock_page(pages[i]); 984 page_cache_release(pages[i]); 985 } 986 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT); 987 return ret; 988 989 } 990 991 int btrfs_defrag_file(struct inode *inode, struct file *file, 992 struct btrfs_ioctl_defrag_range_args *range, 993 u64 newer_than, unsigned long max_to_defrag) 994 { 995 struct btrfs_root *root = BTRFS_I(inode)->root; 996 struct btrfs_super_block *disk_super; 997 struct file_ra_state *ra = NULL; 998 unsigned long last_index; 999 u64 isize = i_size_read(inode); 1000 u64 features; 1001 u64 last_len = 0; 1002 u64 skip = 0; 1003 u64 defrag_end = 0; 1004 u64 newer_off = range->start; 1005 unsigned long i; 1006 unsigned long ra_index = 0; 1007 int ret; 1008 int defrag_count = 0; 1009 int compress_type = BTRFS_COMPRESS_ZLIB; 1010 int extent_thresh = range->extent_thresh; 1011 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; 1012 int cluster = max_cluster; 1013 u64 new_align = ~((u64)128 * 1024 - 1); 1014 struct page **pages = NULL; 1015 1016 if (extent_thresh == 0) 1017 extent_thresh = 256 * 1024; 1018 1019 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1020 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1021 return -EINVAL; 1022 if (range->compress_type) 1023 compress_type = range->compress_type; 1024 } 1025 1026 if (isize == 0) 1027 return 0; 1028 1029 /* 1030 * if we were not given a file, allocate a readahead 1031 * context 1032 */ 1033 if (!file) { 1034 ra = kzalloc(sizeof(*ra), GFP_NOFS); 1035 if (!ra) 1036 return -ENOMEM; 1037 file_ra_state_init(ra, inode->i_mapping); 1038 } else { 1039 ra = &file->f_ra; 1040 } 1041 1042 pages = kmalloc(sizeof(struct page *) * max_cluster, 1043 GFP_NOFS); 1044 if (!pages) { 1045 ret = -ENOMEM; 1046 goto out_ra; 1047 } 1048 1049 /* find the last page to defrag */ 1050 if (range->start + range->len > range->start) { 1051 last_index = min_t(u64, isize - 1, 1052 range->start + range->len - 1) >> PAGE_CACHE_SHIFT; 1053 } else { 1054 last_index = (isize - 1) >> PAGE_CACHE_SHIFT; 1055 } 1056 1057 if (newer_than) { 1058 ret = find_new_extents(root, inode, newer_than, 1059 &newer_off, 64 * 1024); 1060 if (!ret) { 1061 range->start = newer_off; 1062 /* 1063 * we always align our defrag to help keep 1064 * the extents in the file evenly spaced 1065 */ 1066 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1067 } else 1068 goto out_ra; 1069 } else { 1070 i = range->start >> PAGE_CACHE_SHIFT; 1071 } 1072 if (!max_to_defrag) 1073 max_to_defrag = last_index + 1; 1074 1075 /* 1076 * make writeback starts from i, so the defrag range can be 1077 * written sequentially. 1078 */ 1079 if (i < inode->i_mapping->writeback_index) 1080 inode->i_mapping->writeback_index = i; 1081 1082 while (i <= last_index && defrag_count < max_to_defrag && 1083 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> 1084 PAGE_CACHE_SHIFT)) { 1085 /* 1086 * make sure we stop running if someone unmounts 1087 * the FS 1088 */ 1089 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1090 break; 1091 1092 if (!newer_than && 1093 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, 1094 PAGE_CACHE_SIZE, 1095 extent_thresh, 1096 &last_len, &skip, 1097 &defrag_end)) { 1098 unsigned long next; 1099 /* 1100 * the should_defrag function tells us how much to skip 1101 * bump our counter by the suggested amount 1102 */ 1103 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 1104 i = max(i + 1, next); 1105 continue; 1106 } 1107 1108 if (!newer_than) { 1109 cluster = (PAGE_CACHE_ALIGN(defrag_end) >> 1110 PAGE_CACHE_SHIFT) - i; 1111 cluster = min(cluster, max_cluster); 1112 } else { 1113 cluster = max_cluster; 1114 } 1115 1116 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) 1117 BTRFS_I(inode)->force_compress = compress_type; 1118 1119 if (i + cluster > ra_index) { 1120 ra_index = max(i, ra_index); 1121 btrfs_force_ra(inode->i_mapping, ra, file, ra_index, 1122 cluster); 1123 ra_index += max_cluster; 1124 } 1125 1126 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1127 if (ret < 0) 1128 goto out_ra; 1129 1130 defrag_count += ret; 1131 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret); 1132 1133 if (newer_than) { 1134 if (newer_off == (u64)-1) 1135 break; 1136 1137 newer_off = max(newer_off + 1, 1138 (u64)i << PAGE_CACHE_SHIFT); 1139 1140 ret = find_new_extents(root, inode, 1141 newer_than, &newer_off, 1142 64 * 1024); 1143 if (!ret) { 1144 range->start = newer_off; 1145 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1146 } else { 1147 break; 1148 } 1149 } else { 1150 if (ret > 0) { 1151 i += ret; 1152 last_len += ret << PAGE_CACHE_SHIFT; 1153 } else { 1154 i++; 1155 last_len = 0; 1156 } 1157 } 1158 } 1159 1160 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) 1161 filemap_flush(inode->i_mapping); 1162 1163 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 1164 /* the filemap_flush will queue IO into the worker threads, but 1165 * we have to make sure the IO is actually started and that 1166 * ordered extents get created before we return 1167 */ 1168 atomic_inc(&root->fs_info->async_submit_draining); 1169 while (atomic_read(&root->fs_info->nr_async_submits) || 1170 atomic_read(&root->fs_info->async_delalloc_pages)) { 1171 wait_event(root->fs_info->async_submit_wait, 1172 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 1173 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 1174 } 1175 atomic_dec(&root->fs_info->async_submit_draining); 1176 1177 mutex_lock(&inode->i_mutex); 1178 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; 1179 mutex_unlock(&inode->i_mutex); 1180 } 1181 1182 disk_super = root->fs_info->super_copy; 1183 features = btrfs_super_incompat_flags(disk_super); 1184 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1185 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO; 1186 btrfs_set_super_incompat_flags(disk_super, features); 1187 } 1188 1189 ret = defrag_count; 1190 1191 out_ra: 1192 if (!file) 1193 kfree(ra); 1194 kfree(pages); 1195 return ret; 1196 } 1197 1198 static noinline int btrfs_ioctl_resize(struct btrfs_root *root, 1199 void __user *arg) 1200 { 1201 u64 new_size; 1202 u64 old_size; 1203 u64 devid = 1; 1204 struct btrfs_ioctl_vol_args *vol_args; 1205 struct btrfs_trans_handle *trans; 1206 struct btrfs_device *device = NULL; 1207 char *sizestr; 1208 char *devstr = NULL; 1209 int ret = 0; 1210 int mod = 0; 1211 1212 if (root->fs_info->sb->s_flags & MS_RDONLY) 1213 return -EROFS; 1214 1215 if (!capable(CAP_SYS_ADMIN)) 1216 return -EPERM; 1217 1218 mutex_lock(&root->fs_info->volume_mutex); 1219 if (root->fs_info->balance_ctl) { 1220 printk(KERN_INFO "btrfs: balance in progress\n"); 1221 ret = -EINVAL; 1222 goto out; 1223 } 1224 1225 vol_args = memdup_user(arg, sizeof(*vol_args)); 1226 if (IS_ERR(vol_args)) { 1227 ret = PTR_ERR(vol_args); 1228 goto out; 1229 } 1230 1231 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1232 1233 sizestr = vol_args->name; 1234 devstr = strchr(sizestr, ':'); 1235 if (devstr) { 1236 char *end; 1237 sizestr = devstr + 1; 1238 *devstr = '\0'; 1239 devstr = vol_args->name; 1240 devid = simple_strtoull(devstr, &end, 10); 1241 printk(KERN_INFO "btrfs: resizing devid %llu\n", 1242 (unsigned long long)devid); 1243 } 1244 device = btrfs_find_device(root, devid, NULL, NULL); 1245 if (!device) { 1246 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n", 1247 (unsigned long long)devid); 1248 ret = -EINVAL; 1249 goto out_free; 1250 } 1251 if (!strcmp(sizestr, "max")) 1252 new_size = device->bdev->bd_inode->i_size; 1253 else { 1254 if (sizestr[0] == '-') { 1255 mod = -1; 1256 sizestr++; 1257 } else if (sizestr[0] == '+') { 1258 mod = 1; 1259 sizestr++; 1260 } 1261 new_size = memparse(sizestr, NULL); 1262 if (new_size == 0) { 1263 ret = -EINVAL; 1264 goto out_free; 1265 } 1266 } 1267 1268 old_size = device->total_bytes; 1269 1270 if (mod < 0) { 1271 if (new_size > old_size) { 1272 ret = -EINVAL; 1273 goto out_free; 1274 } 1275 new_size = old_size - new_size; 1276 } else if (mod > 0) { 1277 new_size = old_size + new_size; 1278 } 1279 1280 if (new_size < 256 * 1024 * 1024) { 1281 ret = -EINVAL; 1282 goto out_free; 1283 } 1284 if (new_size > device->bdev->bd_inode->i_size) { 1285 ret = -EFBIG; 1286 goto out_free; 1287 } 1288 1289 do_div(new_size, root->sectorsize); 1290 new_size *= root->sectorsize; 1291 1292 printk(KERN_INFO "btrfs: new size for %s is %llu\n", 1293 device->name, (unsigned long long)new_size); 1294 1295 if (new_size > old_size) { 1296 trans = btrfs_start_transaction(root, 0); 1297 if (IS_ERR(trans)) { 1298 ret = PTR_ERR(trans); 1299 goto out_free; 1300 } 1301 ret = btrfs_grow_device(trans, device, new_size); 1302 btrfs_commit_transaction(trans, root); 1303 } else if (new_size < old_size) { 1304 ret = btrfs_shrink_device(device, new_size); 1305 } 1306 1307 out_free: 1308 kfree(vol_args); 1309 out: 1310 mutex_unlock(&root->fs_info->volume_mutex); 1311 return ret; 1312 } 1313 1314 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1315 char *name, 1316 unsigned long fd, 1317 int subvol, 1318 u64 *transid, 1319 bool readonly) 1320 { 1321 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 1322 struct file *src_file; 1323 int namelen; 1324 int ret = 0; 1325 1326 if (root->fs_info->sb->s_flags & MS_RDONLY) 1327 return -EROFS; 1328 1329 namelen = strlen(name); 1330 if (strchr(name, '/')) { 1331 ret = -EINVAL; 1332 goto out; 1333 } 1334 1335 if (name[0] == '.' && 1336 (namelen == 1 || (name[1] == '.' && namelen == 2))) { 1337 ret = -EEXIST; 1338 goto out; 1339 } 1340 1341 if (subvol) { 1342 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1343 NULL, transid, readonly); 1344 } else { 1345 struct inode *src_inode; 1346 src_file = fget(fd); 1347 if (!src_file) { 1348 ret = -EINVAL; 1349 goto out; 1350 } 1351 1352 src_inode = src_file->f_path.dentry->d_inode; 1353 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { 1354 printk(KERN_INFO "btrfs: Snapshot src from " 1355 "another FS\n"); 1356 ret = -EINVAL; 1357 fput(src_file); 1358 goto out; 1359 } 1360 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1361 BTRFS_I(src_inode)->root, 1362 transid, readonly); 1363 fput(src_file); 1364 } 1365 out: 1366 return ret; 1367 } 1368 1369 static noinline int btrfs_ioctl_snap_create(struct file *file, 1370 void __user *arg, int subvol) 1371 { 1372 struct btrfs_ioctl_vol_args *vol_args; 1373 int ret; 1374 1375 vol_args = memdup_user(arg, sizeof(*vol_args)); 1376 if (IS_ERR(vol_args)) 1377 return PTR_ERR(vol_args); 1378 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1379 1380 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1381 vol_args->fd, subvol, 1382 NULL, false); 1383 1384 kfree(vol_args); 1385 return ret; 1386 } 1387 1388 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1389 void __user *arg, int subvol) 1390 { 1391 struct btrfs_ioctl_vol_args_v2 *vol_args; 1392 int ret; 1393 u64 transid = 0; 1394 u64 *ptr = NULL; 1395 bool readonly = false; 1396 1397 vol_args = memdup_user(arg, sizeof(*vol_args)); 1398 if (IS_ERR(vol_args)) 1399 return PTR_ERR(vol_args); 1400 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1401 1402 if (vol_args->flags & 1403 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) { 1404 ret = -EOPNOTSUPP; 1405 goto out; 1406 } 1407 1408 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1409 ptr = &transid; 1410 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1411 readonly = true; 1412 1413 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1414 vol_args->fd, subvol, 1415 ptr, readonly); 1416 1417 if (ret == 0 && ptr && 1418 copy_to_user(arg + 1419 offsetof(struct btrfs_ioctl_vol_args_v2, 1420 transid), ptr, sizeof(*ptr))) 1421 ret = -EFAULT; 1422 out: 1423 kfree(vol_args); 1424 return ret; 1425 } 1426 1427 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1428 void __user *arg) 1429 { 1430 struct inode *inode = fdentry(file)->d_inode; 1431 struct btrfs_root *root = BTRFS_I(inode)->root; 1432 int ret = 0; 1433 u64 flags = 0; 1434 1435 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1436 return -EINVAL; 1437 1438 down_read(&root->fs_info->subvol_sem); 1439 if (btrfs_root_readonly(root)) 1440 flags |= BTRFS_SUBVOL_RDONLY; 1441 up_read(&root->fs_info->subvol_sem); 1442 1443 if (copy_to_user(arg, &flags, sizeof(flags))) 1444 ret = -EFAULT; 1445 1446 return ret; 1447 } 1448 1449 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1450 void __user *arg) 1451 { 1452 struct inode *inode = fdentry(file)->d_inode; 1453 struct btrfs_root *root = BTRFS_I(inode)->root; 1454 struct btrfs_trans_handle *trans; 1455 u64 root_flags; 1456 u64 flags; 1457 int ret = 0; 1458 1459 if (root->fs_info->sb->s_flags & MS_RDONLY) 1460 return -EROFS; 1461 1462 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1463 return -EINVAL; 1464 1465 if (copy_from_user(&flags, arg, sizeof(flags))) 1466 return -EFAULT; 1467 1468 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) 1469 return -EINVAL; 1470 1471 if (flags & ~BTRFS_SUBVOL_RDONLY) 1472 return -EOPNOTSUPP; 1473 1474 if (!inode_owner_or_capable(inode)) 1475 return -EACCES; 1476 1477 down_write(&root->fs_info->subvol_sem); 1478 1479 /* nothing to do */ 1480 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1481 goto out; 1482 1483 root_flags = btrfs_root_flags(&root->root_item); 1484 if (flags & BTRFS_SUBVOL_RDONLY) 1485 btrfs_set_root_flags(&root->root_item, 1486 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1487 else 1488 btrfs_set_root_flags(&root->root_item, 1489 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1490 1491 trans = btrfs_start_transaction(root, 1); 1492 if (IS_ERR(trans)) { 1493 ret = PTR_ERR(trans); 1494 goto out_reset; 1495 } 1496 1497 ret = btrfs_update_root(trans, root->fs_info->tree_root, 1498 &root->root_key, &root->root_item); 1499 1500 btrfs_commit_transaction(trans, root); 1501 out_reset: 1502 if (ret) 1503 btrfs_set_root_flags(&root->root_item, root_flags); 1504 out: 1505 up_write(&root->fs_info->subvol_sem); 1506 return ret; 1507 } 1508 1509 /* 1510 * helper to check if the subvolume references other subvolumes 1511 */ 1512 static noinline int may_destroy_subvol(struct btrfs_root *root) 1513 { 1514 struct btrfs_path *path; 1515 struct btrfs_key key; 1516 int ret; 1517 1518 path = btrfs_alloc_path(); 1519 if (!path) 1520 return -ENOMEM; 1521 1522 key.objectid = root->root_key.objectid; 1523 key.type = BTRFS_ROOT_REF_KEY; 1524 key.offset = (u64)-1; 1525 1526 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, 1527 &key, path, 0, 0); 1528 if (ret < 0) 1529 goto out; 1530 BUG_ON(ret == 0); 1531 1532 ret = 0; 1533 if (path->slots[0] > 0) { 1534 path->slots[0]--; 1535 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 1536 if (key.objectid == root->root_key.objectid && 1537 key.type == BTRFS_ROOT_REF_KEY) 1538 ret = -ENOTEMPTY; 1539 } 1540 out: 1541 btrfs_free_path(path); 1542 return ret; 1543 } 1544 1545 static noinline int key_in_sk(struct btrfs_key *key, 1546 struct btrfs_ioctl_search_key *sk) 1547 { 1548 struct btrfs_key test; 1549 int ret; 1550 1551 test.objectid = sk->min_objectid; 1552 test.type = sk->min_type; 1553 test.offset = sk->min_offset; 1554 1555 ret = btrfs_comp_cpu_keys(key, &test); 1556 if (ret < 0) 1557 return 0; 1558 1559 test.objectid = sk->max_objectid; 1560 test.type = sk->max_type; 1561 test.offset = sk->max_offset; 1562 1563 ret = btrfs_comp_cpu_keys(key, &test); 1564 if (ret > 0) 1565 return 0; 1566 return 1; 1567 } 1568 1569 static noinline int copy_to_sk(struct btrfs_root *root, 1570 struct btrfs_path *path, 1571 struct btrfs_key *key, 1572 struct btrfs_ioctl_search_key *sk, 1573 char *buf, 1574 unsigned long *sk_offset, 1575 int *num_found) 1576 { 1577 u64 found_transid; 1578 struct extent_buffer *leaf; 1579 struct btrfs_ioctl_search_header sh; 1580 unsigned long item_off; 1581 unsigned long item_len; 1582 int nritems; 1583 int i; 1584 int slot; 1585 int ret = 0; 1586 1587 leaf = path->nodes[0]; 1588 slot = path->slots[0]; 1589 nritems = btrfs_header_nritems(leaf); 1590 1591 if (btrfs_header_generation(leaf) > sk->max_transid) { 1592 i = nritems; 1593 goto advance_key; 1594 } 1595 found_transid = btrfs_header_generation(leaf); 1596 1597 for (i = slot; i < nritems; i++) { 1598 item_off = btrfs_item_ptr_offset(leaf, i); 1599 item_len = btrfs_item_size_nr(leaf, i); 1600 1601 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) 1602 item_len = 0; 1603 1604 if (sizeof(sh) + item_len + *sk_offset > 1605 BTRFS_SEARCH_ARGS_BUFSIZE) { 1606 ret = 1; 1607 goto overflow; 1608 } 1609 1610 btrfs_item_key_to_cpu(leaf, key, i); 1611 if (!key_in_sk(key, sk)) 1612 continue; 1613 1614 sh.objectid = key->objectid; 1615 sh.offset = key->offset; 1616 sh.type = key->type; 1617 sh.len = item_len; 1618 sh.transid = found_transid; 1619 1620 /* copy search result header */ 1621 memcpy(buf + *sk_offset, &sh, sizeof(sh)); 1622 *sk_offset += sizeof(sh); 1623 1624 if (item_len) { 1625 char *p = buf + *sk_offset; 1626 /* copy the item */ 1627 read_extent_buffer(leaf, p, 1628 item_off, item_len); 1629 *sk_offset += item_len; 1630 } 1631 (*num_found)++; 1632 1633 if (*num_found >= sk->nr_items) 1634 break; 1635 } 1636 advance_key: 1637 ret = 0; 1638 if (key->offset < (u64)-1 && key->offset < sk->max_offset) 1639 key->offset++; 1640 else if (key->type < (u8)-1 && key->type < sk->max_type) { 1641 key->offset = 0; 1642 key->type++; 1643 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { 1644 key->offset = 0; 1645 key->type = 0; 1646 key->objectid++; 1647 } else 1648 ret = 1; 1649 overflow: 1650 return ret; 1651 } 1652 1653 static noinline int search_ioctl(struct inode *inode, 1654 struct btrfs_ioctl_search_args *args) 1655 { 1656 struct btrfs_root *root; 1657 struct btrfs_key key; 1658 struct btrfs_key max_key; 1659 struct btrfs_path *path; 1660 struct btrfs_ioctl_search_key *sk = &args->key; 1661 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; 1662 int ret; 1663 int num_found = 0; 1664 unsigned long sk_offset = 0; 1665 1666 path = btrfs_alloc_path(); 1667 if (!path) 1668 return -ENOMEM; 1669 1670 if (sk->tree_id == 0) { 1671 /* search the root of the inode that was passed */ 1672 root = BTRFS_I(inode)->root; 1673 } else { 1674 key.objectid = sk->tree_id; 1675 key.type = BTRFS_ROOT_ITEM_KEY; 1676 key.offset = (u64)-1; 1677 root = btrfs_read_fs_root_no_name(info, &key); 1678 if (IS_ERR(root)) { 1679 printk(KERN_ERR "could not find root %llu\n", 1680 sk->tree_id); 1681 btrfs_free_path(path); 1682 return -ENOENT; 1683 } 1684 } 1685 1686 key.objectid = sk->min_objectid; 1687 key.type = sk->min_type; 1688 key.offset = sk->min_offset; 1689 1690 max_key.objectid = sk->max_objectid; 1691 max_key.type = sk->max_type; 1692 max_key.offset = sk->max_offset; 1693 1694 path->keep_locks = 1; 1695 1696 while(1) { 1697 ret = btrfs_search_forward(root, &key, &max_key, path, 0, 1698 sk->min_transid); 1699 if (ret != 0) { 1700 if (ret > 0) 1701 ret = 0; 1702 goto err; 1703 } 1704 ret = copy_to_sk(root, path, &key, sk, args->buf, 1705 &sk_offset, &num_found); 1706 btrfs_release_path(path); 1707 if (ret || num_found >= sk->nr_items) 1708 break; 1709 1710 } 1711 ret = 0; 1712 err: 1713 sk->nr_items = num_found; 1714 btrfs_free_path(path); 1715 return ret; 1716 } 1717 1718 static noinline int btrfs_ioctl_tree_search(struct file *file, 1719 void __user *argp) 1720 { 1721 struct btrfs_ioctl_search_args *args; 1722 struct inode *inode; 1723 int ret; 1724 1725 if (!capable(CAP_SYS_ADMIN)) 1726 return -EPERM; 1727 1728 args = memdup_user(argp, sizeof(*args)); 1729 if (IS_ERR(args)) 1730 return PTR_ERR(args); 1731 1732 inode = fdentry(file)->d_inode; 1733 ret = search_ioctl(inode, args); 1734 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1735 ret = -EFAULT; 1736 kfree(args); 1737 return ret; 1738 } 1739 1740 /* 1741 * Search INODE_REFs to identify path name of 'dirid' directory 1742 * in a 'tree_id' tree. and sets path name to 'name'. 1743 */ 1744 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 1745 u64 tree_id, u64 dirid, char *name) 1746 { 1747 struct btrfs_root *root; 1748 struct btrfs_key key; 1749 char *ptr; 1750 int ret = -1; 1751 int slot; 1752 int len; 1753 int total_len = 0; 1754 struct btrfs_inode_ref *iref; 1755 struct extent_buffer *l; 1756 struct btrfs_path *path; 1757 1758 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 1759 name[0]='\0'; 1760 return 0; 1761 } 1762 1763 path = btrfs_alloc_path(); 1764 if (!path) 1765 return -ENOMEM; 1766 1767 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; 1768 1769 key.objectid = tree_id; 1770 key.type = BTRFS_ROOT_ITEM_KEY; 1771 key.offset = (u64)-1; 1772 root = btrfs_read_fs_root_no_name(info, &key); 1773 if (IS_ERR(root)) { 1774 printk(KERN_ERR "could not find root %llu\n", tree_id); 1775 ret = -ENOENT; 1776 goto out; 1777 } 1778 1779 key.objectid = dirid; 1780 key.type = BTRFS_INODE_REF_KEY; 1781 key.offset = (u64)-1; 1782 1783 while(1) { 1784 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1785 if (ret < 0) 1786 goto out; 1787 1788 l = path->nodes[0]; 1789 slot = path->slots[0]; 1790 if (ret > 0 && slot > 0) 1791 slot--; 1792 btrfs_item_key_to_cpu(l, &key, slot); 1793 1794 if (ret > 0 && (key.objectid != dirid || 1795 key.type != BTRFS_INODE_REF_KEY)) { 1796 ret = -ENOENT; 1797 goto out; 1798 } 1799 1800 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 1801 len = btrfs_inode_ref_name_len(l, iref); 1802 ptr -= len + 1; 1803 total_len += len + 1; 1804 if (ptr < name) 1805 goto out; 1806 1807 *(ptr + len) = '/'; 1808 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len); 1809 1810 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 1811 break; 1812 1813 btrfs_release_path(path); 1814 key.objectid = key.offset; 1815 key.offset = (u64)-1; 1816 dirid = key.objectid; 1817 } 1818 if (ptr < name) 1819 goto out; 1820 memmove(name, ptr, total_len); 1821 name[total_len]='\0'; 1822 ret = 0; 1823 out: 1824 btrfs_free_path(path); 1825 return ret; 1826 } 1827 1828 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 1829 void __user *argp) 1830 { 1831 struct btrfs_ioctl_ino_lookup_args *args; 1832 struct inode *inode; 1833 int ret; 1834 1835 if (!capable(CAP_SYS_ADMIN)) 1836 return -EPERM; 1837 1838 args = memdup_user(argp, sizeof(*args)); 1839 if (IS_ERR(args)) 1840 return PTR_ERR(args); 1841 1842 inode = fdentry(file)->d_inode; 1843 1844 if (args->treeid == 0) 1845 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 1846 1847 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 1848 args->treeid, args->objectid, 1849 args->name); 1850 1851 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1852 ret = -EFAULT; 1853 1854 kfree(args); 1855 return ret; 1856 } 1857 1858 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 1859 void __user *arg) 1860 { 1861 struct dentry *parent = fdentry(file); 1862 struct dentry *dentry; 1863 struct inode *dir = parent->d_inode; 1864 struct inode *inode; 1865 struct btrfs_root *root = BTRFS_I(dir)->root; 1866 struct btrfs_root *dest = NULL; 1867 struct btrfs_ioctl_vol_args *vol_args; 1868 struct btrfs_trans_handle *trans; 1869 int namelen; 1870 int ret; 1871 int err = 0; 1872 1873 vol_args = memdup_user(arg, sizeof(*vol_args)); 1874 if (IS_ERR(vol_args)) 1875 return PTR_ERR(vol_args); 1876 1877 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1878 namelen = strlen(vol_args->name); 1879 if (strchr(vol_args->name, '/') || 1880 strncmp(vol_args->name, "..", namelen) == 0) { 1881 err = -EINVAL; 1882 goto out; 1883 } 1884 1885 err = mnt_want_write_file(file); 1886 if (err) 1887 goto out; 1888 1889 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 1890 dentry = lookup_one_len(vol_args->name, parent, namelen); 1891 if (IS_ERR(dentry)) { 1892 err = PTR_ERR(dentry); 1893 goto out_unlock_dir; 1894 } 1895 1896 if (!dentry->d_inode) { 1897 err = -ENOENT; 1898 goto out_dput; 1899 } 1900 1901 inode = dentry->d_inode; 1902 dest = BTRFS_I(inode)->root; 1903 if (!capable(CAP_SYS_ADMIN)){ 1904 /* 1905 * Regular user. Only allow this with a special mount 1906 * option, when the user has write+exec access to the 1907 * subvol root, and when rmdir(2) would have been 1908 * allowed. 1909 * 1910 * Note that this is _not_ check that the subvol is 1911 * empty or doesn't contain data that we wouldn't 1912 * otherwise be able to delete. 1913 * 1914 * Users who want to delete empty subvols should try 1915 * rmdir(2). 1916 */ 1917 err = -EPERM; 1918 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 1919 goto out_dput; 1920 1921 /* 1922 * Do not allow deletion if the parent dir is the same 1923 * as the dir to be deleted. That means the ioctl 1924 * must be called on the dentry referencing the root 1925 * of the subvol, not a random directory contained 1926 * within it. 1927 */ 1928 err = -EINVAL; 1929 if (root == dest) 1930 goto out_dput; 1931 1932 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 1933 if (err) 1934 goto out_dput; 1935 1936 /* check if subvolume may be deleted by a non-root user */ 1937 err = btrfs_may_delete(dir, dentry, 1); 1938 if (err) 1939 goto out_dput; 1940 } 1941 1942 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 1943 err = -EINVAL; 1944 goto out_dput; 1945 } 1946 1947 mutex_lock(&inode->i_mutex); 1948 err = d_invalidate(dentry); 1949 if (err) 1950 goto out_unlock; 1951 1952 down_write(&root->fs_info->subvol_sem); 1953 1954 err = may_destroy_subvol(dest); 1955 if (err) 1956 goto out_up_write; 1957 1958 trans = btrfs_start_transaction(root, 0); 1959 if (IS_ERR(trans)) { 1960 err = PTR_ERR(trans); 1961 goto out_up_write; 1962 } 1963 trans->block_rsv = &root->fs_info->global_block_rsv; 1964 1965 ret = btrfs_unlink_subvol(trans, root, dir, 1966 dest->root_key.objectid, 1967 dentry->d_name.name, 1968 dentry->d_name.len); 1969 BUG_ON(ret); 1970 1971 btrfs_record_root_in_trans(trans, dest); 1972 1973 memset(&dest->root_item.drop_progress, 0, 1974 sizeof(dest->root_item.drop_progress)); 1975 dest->root_item.drop_level = 0; 1976 btrfs_set_root_refs(&dest->root_item, 0); 1977 1978 if (!xchg(&dest->orphan_item_inserted, 1)) { 1979 ret = btrfs_insert_orphan_item(trans, 1980 root->fs_info->tree_root, 1981 dest->root_key.objectid); 1982 BUG_ON(ret); 1983 } 1984 1985 ret = btrfs_end_transaction(trans, root); 1986 BUG_ON(ret); 1987 inode->i_flags |= S_DEAD; 1988 out_up_write: 1989 up_write(&root->fs_info->subvol_sem); 1990 out_unlock: 1991 mutex_unlock(&inode->i_mutex); 1992 if (!err) { 1993 shrink_dcache_sb(root->fs_info->sb); 1994 btrfs_invalidate_inodes(dest); 1995 d_delete(dentry); 1996 } 1997 out_dput: 1998 dput(dentry); 1999 out_unlock_dir: 2000 mutex_unlock(&dir->i_mutex); 2001 mnt_drop_write_file(file); 2002 out: 2003 kfree(vol_args); 2004 return err; 2005 } 2006 2007 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 2008 { 2009 struct inode *inode = fdentry(file)->d_inode; 2010 struct btrfs_root *root = BTRFS_I(inode)->root; 2011 struct btrfs_ioctl_defrag_range_args *range; 2012 int ret; 2013 2014 if (btrfs_root_readonly(root)) 2015 return -EROFS; 2016 2017 ret = mnt_want_write_file(file); 2018 if (ret) 2019 return ret; 2020 2021 switch (inode->i_mode & S_IFMT) { 2022 case S_IFDIR: 2023 if (!capable(CAP_SYS_ADMIN)) { 2024 ret = -EPERM; 2025 goto out; 2026 } 2027 ret = btrfs_defrag_root(root, 0); 2028 if (ret) 2029 goto out; 2030 ret = btrfs_defrag_root(root->fs_info->extent_root, 0); 2031 break; 2032 case S_IFREG: 2033 if (!(file->f_mode & FMODE_WRITE)) { 2034 ret = -EINVAL; 2035 goto out; 2036 } 2037 2038 range = kzalloc(sizeof(*range), GFP_KERNEL); 2039 if (!range) { 2040 ret = -ENOMEM; 2041 goto out; 2042 } 2043 2044 if (argp) { 2045 if (copy_from_user(range, argp, 2046 sizeof(*range))) { 2047 ret = -EFAULT; 2048 kfree(range); 2049 goto out; 2050 } 2051 /* compression requires us to start the IO */ 2052 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2053 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2054 range->extent_thresh = (u32)-1; 2055 } 2056 } else { 2057 /* the rest are all set to zero by kzalloc */ 2058 range->len = (u64)-1; 2059 } 2060 ret = btrfs_defrag_file(fdentry(file)->d_inode, file, 2061 range, 0, 0); 2062 if (ret > 0) 2063 ret = 0; 2064 kfree(range); 2065 break; 2066 default: 2067 ret = -EINVAL; 2068 } 2069 out: 2070 mnt_drop_write_file(file); 2071 return ret; 2072 } 2073 2074 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 2075 { 2076 struct btrfs_ioctl_vol_args *vol_args; 2077 int ret; 2078 2079 if (!capable(CAP_SYS_ADMIN)) 2080 return -EPERM; 2081 2082 mutex_lock(&root->fs_info->volume_mutex); 2083 if (root->fs_info->balance_ctl) { 2084 printk(KERN_INFO "btrfs: balance in progress\n"); 2085 ret = -EINVAL; 2086 goto out; 2087 } 2088 2089 vol_args = memdup_user(arg, sizeof(*vol_args)); 2090 if (IS_ERR(vol_args)) { 2091 ret = PTR_ERR(vol_args); 2092 goto out; 2093 } 2094 2095 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2096 ret = btrfs_init_new_device(root, vol_args->name); 2097 2098 kfree(vol_args); 2099 out: 2100 mutex_unlock(&root->fs_info->volume_mutex); 2101 return ret; 2102 } 2103 2104 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) 2105 { 2106 struct btrfs_ioctl_vol_args *vol_args; 2107 int ret; 2108 2109 if (!capable(CAP_SYS_ADMIN)) 2110 return -EPERM; 2111 2112 if (root->fs_info->sb->s_flags & MS_RDONLY) 2113 return -EROFS; 2114 2115 mutex_lock(&root->fs_info->volume_mutex); 2116 if (root->fs_info->balance_ctl) { 2117 printk(KERN_INFO "btrfs: balance in progress\n"); 2118 ret = -EINVAL; 2119 goto out; 2120 } 2121 2122 vol_args = memdup_user(arg, sizeof(*vol_args)); 2123 if (IS_ERR(vol_args)) { 2124 ret = PTR_ERR(vol_args); 2125 goto out; 2126 } 2127 2128 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2129 ret = btrfs_rm_device(root, vol_args->name); 2130 2131 kfree(vol_args); 2132 out: 2133 mutex_unlock(&root->fs_info->volume_mutex); 2134 return ret; 2135 } 2136 2137 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) 2138 { 2139 struct btrfs_ioctl_fs_info_args *fi_args; 2140 struct btrfs_device *device; 2141 struct btrfs_device *next; 2142 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2143 int ret = 0; 2144 2145 if (!capable(CAP_SYS_ADMIN)) 2146 return -EPERM; 2147 2148 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 2149 if (!fi_args) 2150 return -ENOMEM; 2151 2152 fi_args->num_devices = fs_devices->num_devices; 2153 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); 2154 2155 mutex_lock(&fs_devices->device_list_mutex); 2156 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 2157 if (device->devid > fi_args->max_id) 2158 fi_args->max_id = device->devid; 2159 } 2160 mutex_unlock(&fs_devices->device_list_mutex); 2161 2162 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 2163 ret = -EFAULT; 2164 2165 kfree(fi_args); 2166 return ret; 2167 } 2168 2169 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) 2170 { 2171 struct btrfs_ioctl_dev_info_args *di_args; 2172 struct btrfs_device *dev; 2173 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2174 int ret = 0; 2175 char *s_uuid = NULL; 2176 char empty_uuid[BTRFS_UUID_SIZE] = {0}; 2177 2178 if (!capable(CAP_SYS_ADMIN)) 2179 return -EPERM; 2180 2181 di_args = memdup_user(arg, sizeof(*di_args)); 2182 if (IS_ERR(di_args)) 2183 return PTR_ERR(di_args); 2184 2185 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0) 2186 s_uuid = di_args->uuid; 2187 2188 mutex_lock(&fs_devices->device_list_mutex); 2189 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL); 2190 mutex_unlock(&fs_devices->device_list_mutex); 2191 2192 if (!dev) { 2193 ret = -ENODEV; 2194 goto out; 2195 } 2196 2197 di_args->devid = dev->devid; 2198 di_args->bytes_used = dev->bytes_used; 2199 di_args->total_bytes = dev->total_bytes; 2200 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 2201 strncpy(di_args->path, dev->name, sizeof(di_args->path)); 2202 2203 out: 2204 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 2205 ret = -EFAULT; 2206 2207 kfree(di_args); 2208 return ret; 2209 } 2210 2211 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 2212 u64 off, u64 olen, u64 destoff) 2213 { 2214 struct inode *inode = fdentry(file)->d_inode; 2215 struct btrfs_root *root = BTRFS_I(inode)->root; 2216 struct file *src_file; 2217 struct inode *src; 2218 struct btrfs_trans_handle *trans; 2219 struct btrfs_path *path; 2220 struct extent_buffer *leaf; 2221 char *buf; 2222 struct btrfs_key key; 2223 u32 nritems; 2224 int slot; 2225 int ret; 2226 u64 len = olen; 2227 u64 bs = root->fs_info->sb->s_blocksize; 2228 u64 hint_byte; 2229 2230 /* 2231 * TODO: 2232 * - split compressed inline extents. annoying: we need to 2233 * decompress into destination's address_space (the file offset 2234 * may change, so source mapping won't do), then recompress (or 2235 * otherwise reinsert) a subrange. 2236 * - allow ranges within the same file to be cloned (provided 2237 * they don't overlap)? 2238 */ 2239 2240 /* the destination must be opened for writing */ 2241 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) 2242 return -EINVAL; 2243 2244 if (btrfs_root_readonly(root)) 2245 return -EROFS; 2246 2247 ret = mnt_want_write_file(file); 2248 if (ret) 2249 return ret; 2250 2251 src_file = fget(srcfd); 2252 if (!src_file) { 2253 ret = -EBADF; 2254 goto out_drop_write; 2255 } 2256 2257 src = src_file->f_dentry->d_inode; 2258 2259 ret = -EINVAL; 2260 if (src == inode) 2261 goto out_fput; 2262 2263 /* the src must be open for reading */ 2264 if (!(src_file->f_mode & FMODE_READ)) 2265 goto out_fput; 2266 2267 /* don't make the dst file partly checksummed */ 2268 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 2269 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) 2270 goto out_fput; 2271 2272 ret = -EISDIR; 2273 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 2274 goto out_fput; 2275 2276 ret = -EXDEV; 2277 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root) 2278 goto out_fput; 2279 2280 ret = -ENOMEM; 2281 buf = vmalloc(btrfs_level_size(root, 0)); 2282 if (!buf) 2283 goto out_fput; 2284 2285 path = btrfs_alloc_path(); 2286 if (!path) { 2287 vfree(buf); 2288 goto out_fput; 2289 } 2290 path->reada = 2; 2291 2292 if (inode < src) { 2293 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); 2294 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); 2295 } else { 2296 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); 2297 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); 2298 } 2299 2300 /* determine range to clone */ 2301 ret = -EINVAL; 2302 if (off + len > src->i_size || off + len < off) 2303 goto out_unlock; 2304 if (len == 0) 2305 olen = len = src->i_size - off; 2306 /* if we extend to eof, continue to block boundary */ 2307 if (off + len == src->i_size) 2308 len = ALIGN(src->i_size, bs) - off; 2309 2310 /* verify the end result is block aligned */ 2311 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || 2312 !IS_ALIGNED(destoff, bs)) 2313 goto out_unlock; 2314 2315 if (destoff > inode->i_size) { 2316 ret = btrfs_cont_expand(inode, inode->i_size, destoff); 2317 if (ret) 2318 goto out_unlock; 2319 } 2320 2321 /* truncate page cache pages from target inode range */ 2322 truncate_inode_pages_range(&inode->i_data, destoff, 2323 PAGE_CACHE_ALIGN(destoff + len) - 1); 2324 2325 /* do any pending delalloc/csum calc on src, one way or 2326 another, and lock file content */ 2327 while (1) { 2328 struct btrfs_ordered_extent *ordered; 2329 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2330 ordered = btrfs_lookup_first_ordered_extent(src, off+len); 2331 if (!ordered && 2332 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len, 2333 EXTENT_DELALLOC, 0, NULL)) 2334 break; 2335 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2336 if (ordered) 2337 btrfs_put_ordered_extent(ordered); 2338 btrfs_wait_ordered_range(src, off, len); 2339 } 2340 2341 /* clone data */ 2342 key.objectid = btrfs_ino(src); 2343 key.type = BTRFS_EXTENT_DATA_KEY; 2344 key.offset = 0; 2345 2346 while (1) { 2347 /* 2348 * note the key will change type as we walk through the 2349 * tree. 2350 */ 2351 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2352 if (ret < 0) 2353 goto out; 2354 2355 nritems = btrfs_header_nritems(path->nodes[0]); 2356 if (path->slots[0] >= nritems) { 2357 ret = btrfs_next_leaf(root, path); 2358 if (ret < 0) 2359 goto out; 2360 if (ret > 0) 2361 break; 2362 nritems = btrfs_header_nritems(path->nodes[0]); 2363 } 2364 leaf = path->nodes[0]; 2365 slot = path->slots[0]; 2366 2367 btrfs_item_key_to_cpu(leaf, &key, slot); 2368 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || 2369 key.objectid != btrfs_ino(src)) 2370 break; 2371 2372 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { 2373 struct btrfs_file_extent_item *extent; 2374 int type; 2375 u32 size; 2376 struct btrfs_key new_key; 2377 u64 disko = 0, diskl = 0; 2378 u64 datao = 0, datal = 0; 2379 u8 comp; 2380 u64 endoff; 2381 2382 size = btrfs_item_size_nr(leaf, slot); 2383 read_extent_buffer(leaf, buf, 2384 btrfs_item_ptr_offset(leaf, slot), 2385 size); 2386 2387 extent = btrfs_item_ptr(leaf, slot, 2388 struct btrfs_file_extent_item); 2389 comp = btrfs_file_extent_compression(leaf, extent); 2390 type = btrfs_file_extent_type(leaf, extent); 2391 if (type == BTRFS_FILE_EXTENT_REG || 2392 type == BTRFS_FILE_EXTENT_PREALLOC) { 2393 disko = btrfs_file_extent_disk_bytenr(leaf, 2394 extent); 2395 diskl = btrfs_file_extent_disk_num_bytes(leaf, 2396 extent); 2397 datao = btrfs_file_extent_offset(leaf, extent); 2398 datal = btrfs_file_extent_num_bytes(leaf, 2399 extent); 2400 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2401 /* take upper bound, may be compressed */ 2402 datal = btrfs_file_extent_ram_bytes(leaf, 2403 extent); 2404 } 2405 btrfs_release_path(path); 2406 2407 if (key.offset + datal <= off || 2408 key.offset >= off+len) 2409 goto next; 2410 2411 memcpy(&new_key, &key, sizeof(new_key)); 2412 new_key.objectid = btrfs_ino(inode); 2413 if (off <= key.offset) 2414 new_key.offset = key.offset + destoff - off; 2415 else 2416 new_key.offset = destoff; 2417 2418 /* 2419 * 1 - adjusting old extent (we may have to split it) 2420 * 1 - add new extent 2421 * 1 - inode update 2422 */ 2423 trans = btrfs_start_transaction(root, 3); 2424 if (IS_ERR(trans)) { 2425 ret = PTR_ERR(trans); 2426 goto out; 2427 } 2428 2429 if (type == BTRFS_FILE_EXTENT_REG || 2430 type == BTRFS_FILE_EXTENT_PREALLOC) { 2431 /* 2432 * a | --- range to clone ---| b 2433 * | ------------- extent ------------- | 2434 */ 2435 2436 /* substract range b */ 2437 if (key.offset + datal > off + len) 2438 datal = off + len - key.offset; 2439 2440 /* substract range a */ 2441 if (off > key.offset) { 2442 datao += off - key.offset; 2443 datal -= off - key.offset; 2444 } 2445 2446 ret = btrfs_drop_extents(trans, inode, 2447 new_key.offset, 2448 new_key.offset + datal, 2449 &hint_byte, 1); 2450 BUG_ON(ret); 2451 2452 ret = btrfs_insert_empty_item(trans, root, path, 2453 &new_key, size); 2454 BUG_ON(ret); 2455 2456 leaf = path->nodes[0]; 2457 slot = path->slots[0]; 2458 write_extent_buffer(leaf, buf, 2459 btrfs_item_ptr_offset(leaf, slot), 2460 size); 2461 2462 extent = btrfs_item_ptr(leaf, slot, 2463 struct btrfs_file_extent_item); 2464 2465 /* disko == 0 means it's a hole */ 2466 if (!disko) 2467 datao = 0; 2468 2469 btrfs_set_file_extent_offset(leaf, extent, 2470 datao); 2471 btrfs_set_file_extent_num_bytes(leaf, extent, 2472 datal); 2473 if (disko) { 2474 inode_add_bytes(inode, datal); 2475 ret = btrfs_inc_extent_ref(trans, root, 2476 disko, diskl, 0, 2477 root->root_key.objectid, 2478 btrfs_ino(inode), 2479 new_key.offset - datao, 2480 0); 2481 BUG_ON(ret); 2482 } 2483 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2484 u64 skip = 0; 2485 u64 trim = 0; 2486 if (off > key.offset) { 2487 skip = off - key.offset; 2488 new_key.offset += skip; 2489 } 2490 2491 if (key.offset + datal > off+len) 2492 trim = key.offset + datal - (off+len); 2493 2494 if (comp && (skip || trim)) { 2495 ret = -EINVAL; 2496 btrfs_end_transaction(trans, root); 2497 goto out; 2498 } 2499 size -= skip + trim; 2500 datal -= skip + trim; 2501 2502 ret = btrfs_drop_extents(trans, inode, 2503 new_key.offset, 2504 new_key.offset + datal, 2505 &hint_byte, 1); 2506 BUG_ON(ret); 2507 2508 ret = btrfs_insert_empty_item(trans, root, path, 2509 &new_key, size); 2510 BUG_ON(ret); 2511 2512 if (skip) { 2513 u32 start = 2514 btrfs_file_extent_calc_inline_size(0); 2515 memmove(buf+start, buf+start+skip, 2516 datal); 2517 } 2518 2519 leaf = path->nodes[0]; 2520 slot = path->slots[0]; 2521 write_extent_buffer(leaf, buf, 2522 btrfs_item_ptr_offset(leaf, slot), 2523 size); 2524 inode_add_bytes(inode, datal); 2525 } 2526 2527 btrfs_mark_buffer_dirty(leaf); 2528 btrfs_release_path(path); 2529 2530 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 2531 2532 /* 2533 * we round up to the block size at eof when 2534 * determining which extents to clone above, 2535 * but shouldn't round up the file size 2536 */ 2537 endoff = new_key.offset + datal; 2538 if (endoff > destoff+olen) 2539 endoff = destoff+olen; 2540 if (endoff > inode->i_size) 2541 btrfs_i_size_write(inode, endoff); 2542 2543 ret = btrfs_update_inode(trans, root, inode); 2544 BUG_ON(ret); 2545 btrfs_end_transaction(trans, root); 2546 } 2547 next: 2548 btrfs_release_path(path); 2549 key.offset++; 2550 } 2551 ret = 0; 2552 out: 2553 btrfs_release_path(path); 2554 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); 2555 out_unlock: 2556 mutex_unlock(&src->i_mutex); 2557 mutex_unlock(&inode->i_mutex); 2558 vfree(buf); 2559 btrfs_free_path(path); 2560 out_fput: 2561 fput(src_file); 2562 out_drop_write: 2563 mnt_drop_write_file(file); 2564 return ret; 2565 } 2566 2567 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) 2568 { 2569 struct btrfs_ioctl_clone_range_args args; 2570 2571 if (copy_from_user(&args, argp, sizeof(args))) 2572 return -EFAULT; 2573 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, 2574 args.src_length, args.dest_offset); 2575 } 2576 2577 /* 2578 * there are many ways the trans_start and trans_end ioctls can lead 2579 * to deadlocks. They should only be used by applications that 2580 * basically own the machine, and have a very in depth understanding 2581 * of all the possible deadlocks and enospc problems. 2582 */ 2583 static long btrfs_ioctl_trans_start(struct file *file) 2584 { 2585 struct inode *inode = fdentry(file)->d_inode; 2586 struct btrfs_root *root = BTRFS_I(inode)->root; 2587 struct btrfs_trans_handle *trans; 2588 int ret; 2589 2590 ret = -EPERM; 2591 if (!capable(CAP_SYS_ADMIN)) 2592 goto out; 2593 2594 ret = -EINPROGRESS; 2595 if (file->private_data) 2596 goto out; 2597 2598 ret = -EROFS; 2599 if (btrfs_root_readonly(root)) 2600 goto out; 2601 2602 ret = mnt_want_write_file(file); 2603 if (ret) 2604 goto out; 2605 2606 atomic_inc(&root->fs_info->open_ioctl_trans); 2607 2608 ret = -ENOMEM; 2609 trans = btrfs_start_ioctl_transaction(root); 2610 if (IS_ERR(trans)) 2611 goto out_drop; 2612 2613 file->private_data = trans; 2614 return 0; 2615 2616 out_drop: 2617 atomic_dec(&root->fs_info->open_ioctl_trans); 2618 mnt_drop_write_file(file); 2619 out: 2620 return ret; 2621 } 2622 2623 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) 2624 { 2625 struct inode *inode = fdentry(file)->d_inode; 2626 struct btrfs_root *root = BTRFS_I(inode)->root; 2627 struct btrfs_root *new_root; 2628 struct btrfs_dir_item *di; 2629 struct btrfs_trans_handle *trans; 2630 struct btrfs_path *path; 2631 struct btrfs_key location; 2632 struct btrfs_disk_key disk_key; 2633 struct btrfs_super_block *disk_super; 2634 u64 features; 2635 u64 objectid = 0; 2636 u64 dir_id; 2637 2638 if (!capable(CAP_SYS_ADMIN)) 2639 return -EPERM; 2640 2641 if (copy_from_user(&objectid, argp, sizeof(objectid))) 2642 return -EFAULT; 2643 2644 if (!objectid) 2645 objectid = root->root_key.objectid; 2646 2647 location.objectid = objectid; 2648 location.type = BTRFS_ROOT_ITEM_KEY; 2649 location.offset = (u64)-1; 2650 2651 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); 2652 if (IS_ERR(new_root)) 2653 return PTR_ERR(new_root); 2654 2655 if (btrfs_root_refs(&new_root->root_item) == 0) 2656 return -ENOENT; 2657 2658 path = btrfs_alloc_path(); 2659 if (!path) 2660 return -ENOMEM; 2661 path->leave_spinning = 1; 2662 2663 trans = btrfs_start_transaction(root, 1); 2664 if (IS_ERR(trans)) { 2665 btrfs_free_path(path); 2666 return PTR_ERR(trans); 2667 } 2668 2669 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 2670 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, 2671 dir_id, "default", 7, 1); 2672 if (IS_ERR_OR_NULL(di)) { 2673 btrfs_free_path(path); 2674 btrfs_end_transaction(trans, root); 2675 printk(KERN_ERR "Umm, you don't have the default dir item, " 2676 "this isn't going to work\n"); 2677 return -ENOENT; 2678 } 2679 2680 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); 2681 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); 2682 btrfs_mark_buffer_dirty(path->nodes[0]); 2683 btrfs_free_path(path); 2684 2685 disk_super = root->fs_info->super_copy; 2686 features = btrfs_super_incompat_flags(disk_super); 2687 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) { 2688 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL; 2689 btrfs_set_super_incompat_flags(disk_super, features); 2690 } 2691 btrfs_end_transaction(trans, root); 2692 2693 return 0; 2694 } 2695 2696 static void get_block_group_info(struct list_head *groups_list, 2697 struct btrfs_ioctl_space_info *space) 2698 { 2699 struct btrfs_block_group_cache *block_group; 2700 2701 space->total_bytes = 0; 2702 space->used_bytes = 0; 2703 space->flags = 0; 2704 list_for_each_entry(block_group, groups_list, list) { 2705 space->flags = block_group->flags; 2706 space->total_bytes += block_group->key.offset; 2707 space->used_bytes += 2708 btrfs_block_group_used(&block_group->item); 2709 } 2710 } 2711 2712 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) 2713 { 2714 struct btrfs_ioctl_space_args space_args; 2715 struct btrfs_ioctl_space_info space; 2716 struct btrfs_ioctl_space_info *dest; 2717 struct btrfs_ioctl_space_info *dest_orig; 2718 struct btrfs_ioctl_space_info __user *user_dest; 2719 struct btrfs_space_info *info; 2720 u64 types[] = {BTRFS_BLOCK_GROUP_DATA, 2721 BTRFS_BLOCK_GROUP_SYSTEM, 2722 BTRFS_BLOCK_GROUP_METADATA, 2723 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; 2724 int num_types = 4; 2725 int alloc_size; 2726 int ret = 0; 2727 u64 slot_count = 0; 2728 int i, c; 2729 2730 if (copy_from_user(&space_args, 2731 (struct btrfs_ioctl_space_args __user *)arg, 2732 sizeof(space_args))) 2733 return -EFAULT; 2734 2735 for (i = 0; i < num_types; i++) { 2736 struct btrfs_space_info *tmp; 2737 2738 info = NULL; 2739 rcu_read_lock(); 2740 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 2741 list) { 2742 if (tmp->flags == types[i]) { 2743 info = tmp; 2744 break; 2745 } 2746 } 2747 rcu_read_unlock(); 2748 2749 if (!info) 2750 continue; 2751 2752 down_read(&info->groups_sem); 2753 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 2754 if (!list_empty(&info->block_groups[c])) 2755 slot_count++; 2756 } 2757 up_read(&info->groups_sem); 2758 } 2759 2760 /* space_slots == 0 means they are asking for a count */ 2761 if (space_args.space_slots == 0) { 2762 space_args.total_spaces = slot_count; 2763 goto out; 2764 } 2765 2766 slot_count = min_t(u64, space_args.space_slots, slot_count); 2767 2768 alloc_size = sizeof(*dest) * slot_count; 2769 2770 /* we generally have at most 6 or so space infos, one for each raid 2771 * level. So, a whole page should be more than enough for everyone 2772 */ 2773 if (alloc_size > PAGE_CACHE_SIZE) 2774 return -ENOMEM; 2775 2776 space_args.total_spaces = 0; 2777 dest = kmalloc(alloc_size, GFP_NOFS); 2778 if (!dest) 2779 return -ENOMEM; 2780 dest_orig = dest; 2781 2782 /* now we have a buffer to copy into */ 2783 for (i = 0; i < num_types; i++) { 2784 struct btrfs_space_info *tmp; 2785 2786 if (!slot_count) 2787 break; 2788 2789 info = NULL; 2790 rcu_read_lock(); 2791 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 2792 list) { 2793 if (tmp->flags == types[i]) { 2794 info = tmp; 2795 break; 2796 } 2797 } 2798 rcu_read_unlock(); 2799 2800 if (!info) 2801 continue; 2802 down_read(&info->groups_sem); 2803 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 2804 if (!list_empty(&info->block_groups[c])) { 2805 get_block_group_info(&info->block_groups[c], 2806 &space); 2807 memcpy(dest, &space, sizeof(space)); 2808 dest++; 2809 space_args.total_spaces++; 2810 slot_count--; 2811 } 2812 if (!slot_count) 2813 break; 2814 } 2815 up_read(&info->groups_sem); 2816 } 2817 2818 user_dest = (struct btrfs_ioctl_space_info *) 2819 (arg + sizeof(struct btrfs_ioctl_space_args)); 2820 2821 if (copy_to_user(user_dest, dest_orig, alloc_size)) 2822 ret = -EFAULT; 2823 2824 kfree(dest_orig); 2825 out: 2826 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) 2827 ret = -EFAULT; 2828 2829 return ret; 2830 } 2831 2832 /* 2833 * there are many ways the trans_start and trans_end ioctls can lead 2834 * to deadlocks. They should only be used by applications that 2835 * basically own the machine, and have a very in depth understanding 2836 * of all the possible deadlocks and enospc problems. 2837 */ 2838 long btrfs_ioctl_trans_end(struct file *file) 2839 { 2840 struct inode *inode = fdentry(file)->d_inode; 2841 struct btrfs_root *root = BTRFS_I(inode)->root; 2842 struct btrfs_trans_handle *trans; 2843 2844 trans = file->private_data; 2845 if (!trans) 2846 return -EINVAL; 2847 file->private_data = NULL; 2848 2849 btrfs_end_transaction(trans, root); 2850 2851 atomic_dec(&root->fs_info->open_ioctl_trans); 2852 2853 mnt_drop_write_file(file); 2854 return 0; 2855 } 2856 2857 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp) 2858 { 2859 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 2860 struct btrfs_trans_handle *trans; 2861 u64 transid; 2862 int ret; 2863 2864 trans = btrfs_start_transaction(root, 0); 2865 if (IS_ERR(trans)) 2866 return PTR_ERR(trans); 2867 transid = trans->transid; 2868 ret = btrfs_commit_transaction_async(trans, root, 0); 2869 if (ret) { 2870 btrfs_end_transaction(trans, root); 2871 return ret; 2872 } 2873 2874 if (argp) 2875 if (copy_to_user(argp, &transid, sizeof(transid))) 2876 return -EFAULT; 2877 return 0; 2878 } 2879 2880 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp) 2881 { 2882 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 2883 u64 transid; 2884 2885 if (argp) { 2886 if (copy_from_user(&transid, argp, sizeof(transid))) 2887 return -EFAULT; 2888 } else { 2889 transid = 0; /* current trans */ 2890 } 2891 return btrfs_wait_for_commit(root, transid); 2892 } 2893 2894 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg) 2895 { 2896 int ret; 2897 struct btrfs_ioctl_scrub_args *sa; 2898 2899 if (!capable(CAP_SYS_ADMIN)) 2900 return -EPERM; 2901 2902 sa = memdup_user(arg, sizeof(*sa)); 2903 if (IS_ERR(sa)) 2904 return PTR_ERR(sa); 2905 2906 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end, 2907 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY); 2908 2909 if (copy_to_user(arg, sa, sizeof(*sa))) 2910 ret = -EFAULT; 2911 2912 kfree(sa); 2913 return ret; 2914 } 2915 2916 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg) 2917 { 2918 if (!capable(CAP_SYS_ADMIN)) 2919 return -EPERM; 2920 2921 return btrfs_scrub_cancel(root); 2922 } 2923 2924 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, 2925 void __user *arg) 2926 { 2927 struct btrfs_ioctl_scrub_args *sa; 2928 int ret; 2929 2930 if (!capable(CAP_SYS_ADMIN)) 2931 return -EPERM; 2932 2933 sa = memdup_user(arg, sizeof(*sa)); 2934 if (IS_ERR(sa)) 2935 return PTR_ERR(sa); 2936 2937 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress); 2938 2939 if (copy_to_user(arg, sa, sizeof(*sa))) 2940 ret = -EFAULT; 2941 2942 kfree(sa); 2943 return ret; 2944 } 2945 2946 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) 2947 { 2948 int ret = 0; 2949 int i; 2950 u64 rel_ptr; 2951 int size; 2952 struct btrfs_ioctl_ino_path_args *ipa = NULL; 2953 struct inode_fs_paths *ipath = NULL; 2954 struct btrfs_path *path; 2955 2956 if (!capable(CAP_SYS_ADMIN)) 2957 return -EPERM; 2958 2959 path = btrfs_alloc_path(); 2960 if (!path) { 2961 ret = -ENOMEM; 2962 goto out; 2963 } 2964 2965 ipa = memdup_user(arg, sizeof(*ipa)); 2966 if (IS_ERR(ipa)) { 2967 ret = PTR_ERR(ipa); 2968 ipa = NULL; 2969 goto out; 2970 } 2971 2972 size = min_t(u32, ipa->size, 4096); 2973 ipath = init_ipath(size, root, path); 2974 if (IS_ERR(ipath)) { 2975 ret = PTR_ERR(ipath); 2976 ipath = NULL; 2977 goto out; 2978 } 2979 2980 ret = paths_from_inode(ipa->inum, ipath); 2981 if (ret < 0) 2982 goto out; 2983 2984 for (i = 0; i < ipath->fspath->elem_cnt; ++i) { 2985 rel_ptr = ipath->fspath->val[i] - 2986 (u64)(unsigned long)ipath->fspath->val; 2987 ipath->fspath->val[i] = rel_ptr; 2988 } 2989 2990 ret = copy_to_user((void *)(unsigned long)ipa->fspath, 2991 (void *)(unsigned long)ipath->fspath, size); 2992 if (ret) { 2993 ret = -EFAULT; 2994 goto out; 2995 } 2996 2997 out: 2998 btrfs_free_path(path); 2999 free_ipath(ipath); 3000 kfree(ipa); 3001 3002 return ret; 3003 } 3004 3005 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) 3006 { 3007 struct btrfs_data_container *inodes = ctx; 3008 const size_t c = 3 * sizeof(u64); 3009 3010 if (inodes->bytes_left >= c) { 3011 inodes->bytes_left -= c; 3012 inodes->val[inodes->elem_cnt] = inum; 3013 inodes->val[inodes->elem_cnt + 1] = offset; 3014 inodes->val[inodes->elem_cnt + 2] = root; 3015 inodes->elem_cnt += 3; 3016 } else { 3017 inodes->bytes_missing += c - inodes->bytes_left; 3018 inodes->bytes_left = 0; 3019 inodes->elem_missed += 3; 3020 } 3021 3022 return 0; 3023 } 3024 3025 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 3026 void __user *arg) 3027 { 3028 int ret = 0; 3029 int size; 3030 u64 extent_item_pos; 3031 struct btrfs_ioctl_logical_ino_args *loi; 3032 struct btrfs_data_container *inodes = NULL; 3033 struct btrfs_path *path = NULL; 3034 struct btrfs_key key; 3035 3036 if (!capable(CAP_SYS_ADMIN)) 3037 return -EPERM; 3038 3039 loi = memdup_user(arg, sizeof(*loi)); 3040 if (IS_ERR(loi)) { 3041 ret = PTR_ERR(loi); 3042 loi = NULL; 3043 goto out; 3044 } 3045 3046 path = btrfs_alloc_path(); 3047 if (!path) { 3048 ret = -ENOMEM; 3049 goto out; 3050 } 3051 3052 size = min_t(u32, loi->size, 4096); 3053 inodes = init_data_container(size); 3054 if (IS_ERR(inodes)) { 3055 ret = PTR_ERR(inodes); 3056 inodes = NULL; 3057 goto out; 3058 } 3059 3060 ret = extent_from_logical(root->fs_info, loi->logical, path, &key); 3061 btrfs_release_path(path); 3062 3063 if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) 3064 ret = -ENOENT; 3065 if (ret < 0) 3066 goto out; 3067 3068 extent_item_pos = loi->logical - key.objectid; 3069 ret = iterate_extent_inodes(root->fs_info, path, key.objectid, 3070 extent_item_pos, build_ino_list, 3071 inodes); 3072 3073 if (ret < 0) 3074 goto out; 3075 3076 ret = copy_to_user((void *)(unsigned long)loi->inodes, 3077 (void *)(unsigned long)inodes, size); 3078 if (ret) 3079 ret = -EFAULT; 3080 3081 out: 3082 btrfs_free_path(path); 3083 kfree(inodes); 3084 kfree(loi); 3085 3086 return ret; 3087 } 3088 3089 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3090 struct btrfs_ioctl_balance_args *bargs) 3091 { 3092 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3093 3094 bargs->flags = bctl->flags; 3095 3096 if (atomic_read(&fs_info->balance_running)) 3097 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 3098 if (atomic_read(&fs_info->balance_pause_req)) 3099 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 3100 if (atomic_read(&fs_info->balance_cancel_req)) 3101 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 3102 3103 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 3104 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 3105 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 3106 3107 if (lock) { 3108 spin_lock(&fs_info->balance_lock); 3109 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3110 spin_unlock(&fs_info->balance_lock); 3111 } else { 3112 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3113 } 3114 } 3115 3116 static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg) 3117 { 3118 struct btrfs_fs_info *fs_info = root->fs_info; 3119 struct btrfs_ioctl_balance_args *bargs; 3120 struct btrfs_balance_control *bctl; 3121 int ret; 3122 3123 if (!capable(CAP_SYS_ADMIN)) 3124 return -EPERM; 3125 3126 if (fs_info->sb->s_flags & MS_RDONLY) 3127 return -EROFS; 3128 3129 mutex_lock(&fs_info->volume_mutex); 3130 mutex_lock(&fs_info->balance_mutex); 3131 3132 if (arg) { 3133 bargs = memdup_user(arg, sizeof(*bargs)); 3134 if (IS_ERR(bargs)) { 3135 ret = PTR_ERR(bargs); 3136 goto out; 3137 } 3138 3139 if (bargs->flags & BTRFS_BALANCE_RESUME) { 3140 if (!fs_info->balance_ctl) { 3141 ret = -ENOTCONN; 3142 goto out_bargs; 3143 } 3144 3145 bctl = fs_info->balance_ctl; 3146 spin_lock(&fs_info->balance_lock); 3147 bctl->flags |= BTRFS_BALANCE_RESUME; 3148 spin_unlock(&fs_info->balance_lock); 3149 3150 goto do_balance; 3151 } 3152 } else { 3153 bargs = NULL; 3154 } 3155 3156 if (fs_info->balance_ctl) { 3157 ret = -EINPROGRESS; 3158 goto out_bargs; 3159 } 3160 3161 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3162 if (!bctl) { 3163 ret = -ENOMEM; 3164 goto out_bargs; 3165 } 3166 3167 bctl->fs_info = fs_info; 3168 if (arg) { 3169 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 3170 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 3171 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 3172 3173 bctl->flags = bargs->flags; 3174 } else { 3175 /* balance everything - no filters */ 3176 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 3177 } 3178 3179 do_balance: 3180 ret = btrfs_balance(bctl, bargs); 3181 /* 3182 * bctl is freed in __cancel_balance or in free_fs_info if 3183 * restriper was paused all the way until unmount 3184 */ 3185 if (arg) { 3186 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3187 ret = -EFAULT; 3188 } 3189 3190 out_bargs: 3191 kfree(bargs); 3192 out: 3193 mutex_unlock(&fs_info->balance_mutex); 3194 mutex_unlock(&fs_info->volume_mutex); 3195 return ret; 3196 } 3197 3198 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) 3199 { 3200 if (!capable(CAP_SYS_ADMIN)) 3201 return -EPERM; 3202 3203 switch (cmd) { 3204 case BTRFS_BALANCE_CTL_PAUSE: 3205 return btrfs_pause_balance(root->fs_info); 3206 case BTRFS_BALANCE_CTL_CANCEL: 3207 return btrfs_cancel_balance(root->fs_info); 3208 } 3209 3210 return -EINVAL; 3211 } 3212 3213 static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 3214 void __user *arg) 3215 { 3216 struct btrfs_fs_info *fs_info = root->fs_info; 3217 struct btrfs_ioctl_balance_args *bargs; 3218 int ret = 0; 3219 3220 if (!capable(CAP_SYS_ADMIN)) 3221 return -EPERM; 3222 3223 mutex_lock(&fs_info->balance_mutex); 3224 if (!fs_info->balance_ctl) { 3225 ret = -ENOTCONN; 3226 goto out; 3227 } 3228 3229 bargs = kzalloc(sizeof(*bargs), GFP_NOFS); 3230 if (!bargs) { 3231 ret = -ENOMEM; 3232 goto out; 3233 } 3234 3235 update_ioctl_balance_args(fs_info, 1, bargs); 3236 3237 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3238 ret = -EFAULT; 3239 3240 kfree(bargs); 3241 out: 3242 mutex_unlock(&fs_info->balance_mutex); 3243 return ret; 3244 } 3245 3246 long btrfs_ioctl(struct file *file, unsigned int 3247 cmd, unsigned long arg) 3248 { 3249 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 3250 void __user *argp = (void __user *)arg; 3251 3252 switch (cmd) { 3253 case FS_IOC_GETFLAGS: 3254 return btrfs_ioctl_getflags(file, argp); 3255 case FS_IOC_SETFLAGS: 3256 return btrfs_ioctl_setflags(file, argp); 3257 case FS_IOC_GETVERSION: 3258 return btrfs_ioctl_getversion(file, argp); 3259 case FITRIM: 3260 return btrfs_ioctl_fitrim(file, argp); 3261 case BTRFS_IOC_SNAP_CREATE: 3262 return btrfs_ioctl_snap_create(file, argp, 0); 3263 case BTRFS_IOC_SNAP_CREATE_V2: 3264 return btrfs_ioctl_snap_create_v2(file, argp, 0); 3265 case BTRFS_IOC_SUBVOL_CREATE: 3266 return btrfs_ioctl_snap_create(file, argp, 1); 3267 case BTRFS_IOC_SNAP_DESTROY: 3268 return btrfs_ioctl_snap_destroy(file, argp); 3269 case BTRFS_IOC_SUBVOL_GETFLAGS: 3270 return btrfs_ioctl_subvol_getflags(file, argp); 3271 case BTRFS_IOC_SUBVOL_SETFLAGS: 3272 return btrfs_ioctl_subvol_setflags(file, argp); 3273 case BTRFS_IOC_DEFAULT_SUBVOL: 3274 return btrfs_ioctl_default_subvol(file, argp); 3275 case BTRFS_IOC_DEFRAG: 3276 return btrfs_ioctl_defrag(file, NULL); 3277 case BTRFS_IOC_DEFRAG_RANGE: 3278 return btrfs_ioctl_defrag(file, argp); 3279 case BTRFS_IOC_RESIZE: 3280 return btrfs_ioctl_resize(root, argp); 3281 case BTRFS_IOC_ADD_DEV: 3282 return btrfs_ioctl_add_dev(root, argp); 3283 case BTRFS_IOC_RM_DEV: 3284 return btrfs_ioctl_rm_dev(root, argp); 3285 case BTRFS_IOC_FS_INFO: 3286 return btrfs_ioctl_fs_info(root, argp); 3287 case BTRFS_IOC_DEV_INFO: 3288 return btrfs_ioctl_dev_info(root, argp); 3289 case BTRFS_IOC_BALANCE: 3290 return btrfs_ioctl_balance(root, NULL); 3291 case BTRFS_IOC_CLONE: 3292 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 3293 case BTRFS_IOC_CLONE_RANGE: 3294 return btrfs_ioctl_clone_range(file, argp); 3295 case BTRFS_IOC_TRANS_START: 3296 return btrfs_ioctl_trans_start(file); 3297 case BTRFS_IOC_TRANS_END: 3298 return btrfs_ioctl_trans_end(file); 3299 case BTRFS_IOC_TREE_SEARCH: 3300 return btrfs_ioctl_tree_search(file, argp); 3301 case BTRFS_IOC_INO_LOOKUP: 3302 return btrfs_ioctl_ino_lookup(file, argp); 3303 case BTRFS_IOC_INO_PATHS: 3304 return btrfs_ioctl_ino_to_path(root, argp); 3305 case BTRFS_IOC_LOGICAL_INO: 3306 return btrfs_ioctl_logical_to_ino(root, argp); 3307 case BTRFS_IOC_SPACE_INFO: 3308 return btrfs_ioctl_space_info(root, argp); 3309 case BTRFS_IOC_SYNC: 3310 btrfs_sync_fs(file->f_dentry->d_sb, 1); 3311 return 0; 3312 case BTRFS_IOC_START_SYNC: 3313 return btrfs_ioctl_start_sync(file, argp); 3314 case BTRFS_IOC_WAIT_SYNC: 3315 return btrfs_ioctl_wait_sync(file, argp); 3316 case BTRFS_IOC_SCRUB: 3317 return btrfs_ioctl_scrub(root, argp); 3318 case BTRFS_IOC_SCRUB_CANCEL: 3319 return btrfs_ioctl_scrub_cancel(root, argp); 3320 case BTRFS_IOC_SCRUB_PROGRESS: 3321 return btrfs_ioctl_scrub_progress(root, argp); 3322 case BTRFS_IOC_BALANCE_V2: 3323 return btrfs_ioctl_balance(root, argp); 3324 case BTRFS_IOC_BALANCE_CTL: 3325 return btrfs_ioctl_balance_ctl(root, arg); 3326 case BTRFS_IOC_BALANCE_PROGRESS: 3327 return btrfs_ioctl_balance_progress(root, argp); 3328 } 3329 3330 return -ENOTTY; 3331 } 3332