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 if (IS_ERR(new_root)) { 429 btrfs_abort_transaction(trans, root, PTR_ERR(new_root)); 430 ret = PTR_ERR(new_root); 431 goto fail; 432 } 433 434 btrfs_record_root_in_trans(trans, new_root); 435 436 ret = btrfs_create_subvol_root(trans, new_root, new_dirid); 437 if (ret) { 438 /* We potentially lose an unused inode item here */ 439 btrfs_abort_transaction(trans, root, ret); 440 goto fail; 441 } 442 443 /* 444 * insert the directory item 445 */ 446 ret = btrfs_set_inode_index(dir, &index); 447 if (ret) { 448 btrfs_abort_transaction(trans, root, ret); 449 goto fail; 450 } 451 452 ret = btrfs_insert_dir_item(trans, root, 453 name, namelen, dir, &key, 454 BTRFS_FT_DIR, index); 455 if (ret) { 456 btrfs_abort_transaction(trans, root, ret); 457 goto fail; 458 } 459 460 btrfs_i_size_write(dir, dir->i_size + namelen * 2); 461 ret = btrfs_update_inode(trans, root, dir); 462 BUG_ON(ret); 463 464 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, 465 objectid, root->root_key.objectid, 466 btrfs_ino(dir), index, name, namelen); 467 468 BUG_ON(ret); 469 470 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry)); 471 fail: 472 if (async_transid) { 473 *async_transid = trans->transid; 474 err = btrfs_commit_transaction_async(trans, root, 1); 475 } else { 476 err = btrfs_commit_transaction(trans, root); 477 } 478 if (err && !ret) 479 ret = err; 480 return ret; 481 } 482 483 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry, 484 char *name, int namelen, u64 *async_transid, 485 bool readonly) 486 { 487 struct inode *inode; 488 struct btrfs_pending_snapshot *pending_snapshot; 489 struct btrfs_trans_handle *trans; 490 int ret; 491 492 if (!root->ref_cows) 493 return -EINVAL; 494 495 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); 496 if (!pending_snapshot) 497 return -ENOMEM; 498 499 btrfs_init_block_rsv(&pending_snapshot->block_rsv); 500 pending_snapshot->dentry = dentry; 501 pending_snapshot->root = root; 502 pending_snapshot->readonly = readonly; 503 504 trans = btrfs_start_transaction(root->fs_info->extent_root, 5); 505 if (IS_ERR(trans)) { 506 ret = PTR_ERR(trans); 507 goto fail; 508 } 509 510 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot); 511 BUG_ON(ret); 512 513 spin_lock(&root->fs_info->trans_lock); 514 list_add(&pending_snapshot->list, 515 &trans->transaction->pending_snapshots); 516 spin_unlock(&root->fs_info->trans_lock); 517 if (async_transid) { 518 *async_transid = trans->transid; 519 ret = btrfs_commit_transaction_async(trans, 520 root->fs_info->extent_root, 1); 521 } else { 522 ret = btrfs_commit_transaction(trans, 523 root->fs_info->extent_root); 524 } 525 BUG_ON(ret); 526 527 ret = pending_snapshot->error; 528 if (ret) 529 goto fail; 530 531 ret = btrfs_orphan_cleanup(pending_snapshot->snap); 532 if (ret) 533 goto fail; 534 535 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry); 536 if (IS_ERR(inode)) { 537 ret = PTR_ERR(inode); 538 goto fail; 539 } 540 BUG_ON(!inode); 541 d_instantiate(dentry, inode); 542 ret = 0; 543 fail: 544 kfree(pending_snapshot); 545 return ret; 546 } 547 548 /* copy of check_sticky in fs/namei.c() 549 * It's inline, so penalty for filesystems that don't use sticky bit is 550 * minimal. 551 */ 552 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode) 553 { 554 uid_t fsuid = current_fsuid(); 555 556 if (!(dir->i_mode & S_ISVTX)) 557 return 0; 558 if (inode->i_uid == fsuid) 559 return 0; 560 if (dir->i_uid == fsuid) 561 return 0; 562 return !capable(CAP_FOWNER); 563 } 564 565 /* copy of may_delete in fs/namei.c() 566 * Check whether we can remove a link victim from directory dir, check 567 * whether the type of victim is right. 568 * 1. We can't do it if dir is read-only (done in permission()) 569 * 2. We should have write and exec permissions on dir 570 * 3. We can't remove anything from append-only dir 571 * 4. We can't do anything with immutable dir (done in permission()) 572 * 5. If the sticky bit on dir is set we should either 573 * a. be owner of dir, or 574 * b. be owner of victim, or 575 * c. have CAP_FOWNER capability 576 * 6. If the victim is append-only or immutable we can't do antyhing with 577 * links pointing to it. 578 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. 579 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. 580 * 9. We can't remove a root or mountpoint. 581 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by 582 * nfs_async_unlink(). 583 */ 584 585 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir) 586 { 587 int error; 588 589 if (!victim->d_inode) 590 return -ENOENT; 591 592 BUG_ON(victim->d_parent->d_inode != dir); 593 audit_inode_child(victim, dir); 594 595 error = inode_permission(dir, MAY_WRITE | MAY_EXEC); 596 if (error) 597 return error; 598 if (IS_APPEND(dir)) 599 return -EPERM; 600 if (btrfs_check_sticky(dir, victim->d_inode)|| 601 IS_APPEND(victim->d_inode)|| 602 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) 603 return -EPERM; 604 if (isdir) { 605 if (!S_ISDIR(victim->d_inode->i_mode)) 606 return -ENOTDIR; 607 if (IS_ROOT(victim)) 608 return -EBUSY; 609 } else if (S_ISDIR(victim->d_inode->i_mode)) 610 return -EISDIR; 611 if (IS_DEADDIR(dir)) 612 return -ENOENT; 613 if (victim->d_flags & DCACHE_NFSFS_RENAMED) 614 return -EBUSY; 615 return 0; 616 } 617 618 /* copy of may_create in fs/namei.c() */ 619 static inline int btrfs_may_create(struct inode *dir, struct dentry *child) 620 { 621 if (child->d_inode) 622 return -EEXIST; 623 if (IS_DEADDIR(dir)) 624 return -ENOENT; 625 return inode_permission(dir, MAY_WRITE | MAY_EXEC); 626 } 627 628 /* 629 * Create a new subvolume below @parent. This is largely modeled after 630 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup 631 * inside this filesystem so it's quite a bit simpler. 632 */ 633 static noinline int btrfs_mksubvol(struct path *parent, 634 char *name, int namelen, 635 struct btrfs_root *snap_src, 636 u64 *async_transid, bool readonly) 637 { 638 struct inode *dir = parent->dentry->d_inode; 639 struct dentry *dentry; 640 int error; 641 642 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 643 644 dentry = lookup_one_len(name, parent->dentry, namelen); 645 error = PTR_ERR(dentry); 646 if (IS_ERR(dentry)) 647 goto out_unlock; 648 649 error = -EEXIST; 650 if (dentry->d_inode) 651 goto out_dput; 652 653 error = mnt_want_write(parent->mnt); 654 if (error) 655 goto out_dput; 656 657 error = btrfs_may_create(dir, dentry); 658 if (error) 659 goto out_drop_write; 660 661 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 662 663 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) 664 goto out_up_read; 665 666 if (snap_src) { 667 error = create_snapshot(snap_src, dentry, 668 name, namelen, async_transid, readonly); 669 } else { 670 error = create_subvol(BTRFS_I(dir)->root, dentry, 671 name, namelen, async_transid); 672 } 673 if (!error) 674 fsnotify_mkdir(dir, dentry); 675 out_up_read: 676 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 677 out_drop_write: 678 mnt_drop_write(parent->mnt); 679 out_dput: 680 dput(dentry); 681 out_unlock: 682 mutex_unlock(&dir->i_mutex); 683 return error; 684 } 685 686 /* 687 * When we're defragging a range, we don't want to kick it off again 688 * if it is really just waiting for delalloc to send it down. 689 * If we find a nice big extent or delalloc range for the bytes in the 690 * file you want to defrag, we return 0 to let you know to skip this 691 * part of the file 692 */ 693 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh) 694 { 695 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 696 struct extent_map *em = NULL; 697 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 698 u64 end; 699 700 read_lock(&em_tree->lock); 701 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); 702 read_unlock(&em_tree->lock); 703 704 if (em) { 705 end = extent_map_end(em); 706 free_extent_map(em); 707 if (end - offset > thresh) 708 return 0; 709 } 710 /* if we already have a nice delalloc here, just stop */ 711 thresh /= 2; 712 end = count_range_bits(io_tree, &offset, offset + thresh, 713 thresh, EXTENT_DELALLOC, 1); 714 if (end >= thresh) 715 return 0; 716 return 1; 717 } 718 719 /* 720 * helper function to walk through a file and find extents 721 * newer than a specific transid, and smaller than thresh. 722 * 723 * This is used by the defragging code to find new and small 724 * extents 725 */ 726 static int find_new_extents(struct btrfs_root *root, 727 struct inode *inode, u64 newer_than, 728 u64 *off, int thresh) 729 { 730 struct btrfs_path *path; 731 struct btrfs_key min_key; 732 struct btrfs_key max_key; 733 struct extent_buffer *leaf; 734 struct btrfs_file_extent_item *extent; 735 int type; 736 int ret; 737 u64 ino = btrfs_ino(inode); 738 739 path = btrfs_alloc_path(); 740 if (!path) 741 return -ENOMEM; 742 743 min_key.objectid = ino; 744 min_key.type = BTRFS_EXTENT_DATA_KEY; 745 min_key.offset = *off; 746 747 max_key.objectid = ino; 748 max_key.type = (u8)-1; 749 max_key.offset = (u64)-1; 750 751 path->keep_locks = 1; 752 753 while(1) { 754 ret = btrfs_search_forward(root, &min_key, &max_key, 755 path, 0, newer_than); 756 if (ret != 0) 757 goto none; 758 if (min_key.objectid != ino) 759 goto none; 760 if (min_key.type != BTRFS_EXTENT_DATA_KEY) 761 goto none; 762 763 leaf = path->nodes[0]; 764 extent = btrfs_item_ptr(leaf, path->slots[0], 765 struct btrfs_file_extent_item); 766 767 type = btrfs_file_extent_type(leaf, extent); 768 if (type == BTRFS_FILE_EXTENT_REG && 769 btrfs_file_extent_num_bytes(leaf, extent) < thresh && 770 check_defrag_in_cache(inode, min_key.offset, thresh)) { 771 *off = min_key.offset; 772 btrfs_free_path(path); 773 return 0; 774 } 775 776 if (min_key.offset == (u64)-1) 777 goto none; 778 779 min_key.offset++; 780 btrfs_release_path(path); 781 } 782 none: 783 btrfs_free_path(path); 784 return -ENOENT; 785 } 786 787 /* 788 * Validaty check of prev em and next em: 789 * 1) no prev/next em 790 * 2) prev/next em is an hole/inline extent 791 */ 792 static int check_adjacent_extents(struct inode *inode, struct extent_map *em) 793 { 794 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 795 struct extent_map *prev = NULL, *next = NULL; 796 int ret = 0; 797 798 read_lock(&em_tree->lock); 799 prev = lookup_extent_mapping(em_tree, em->start - 1, (u64)-1); 800 next = lookup_extent_mapping(em_tree, em->start + em->len, (u64)-1); 801 read_unlock(&em_tree->lock); 802 803 if ((!prev || prev->block_start >= EXTENT_MAP_LAST_BYTE) && 804 (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)) 805 ret = 1; 806 free_extent_map(prev); 807 free_extent_map(next); 808 809 return ret; 810 } 811 812 static int should_defrag_range(struct inode *inode, u64 start, u64 len, 813 int thresh, u64 *last_len, u64 *skip, 814 u64 *defrag_end) 815 { 816 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 817 struct extent_map *em = NULL; 818 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 819 int ret = 1; 820 821 /* 822 * make sure that once we start defragging an extent, we keep on 823 * defragging it 824 */ 825 if (start < *defrag_end) 826 return 1; 827 828 *skip = 0; 829 830 /* 831 * hopefully we have this extent in the tree already, try without 832 * the full extent lock 833 */ 834 read_lock(&em_tree->lock); 835 em = lookup_extent_mapping(em_tree, start, len); 836 read_unlock(&em_tree->lock); 837 838 if (!em) { 839 /* get the big lock and read metadata off disk */ 840 lock_extent(io_tree, start, start + len - 1); 841 em = btrfs_get_extent(inode, NULL, 0, start, len, 0); 842 unlock_extent(io_tree, start, start + len - 1); 843 844 if (IS_ERR(em)) 845 return 0; 846 } 847 848 /* this will cover holes, and inline extents */ 849 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 850 ret = 0; 851 goto out; 852 } 853 854 /* If we have nothing to merge with us, just skip. */ 855 if (check_adjacent_extents(inode, em)) { 856 ret = 0; 857 goto out; 858 } 859 860 /* 861 * we hit a real extent, if it is big don't bother defragging it again 862 */ 863 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh) 864 ret = 0; 865 866 out: 867 /* 868 * last_len ends up being a counter of how many bytes we've defragged. 869 * every time we choose not to defrag an extent, we reset *last_len 870 * so that the next tiny extent will force a defrag. 871 * 872 * The end result of this is that tiny extents before a single big 873 * extent will force at least part of that big extent to be defragged. 874 */ 875 if (ret) { 876 *defrag_end = extent_map_end(em); 877 } else { 878 *last_len = 0; 879 *skip = extent_map_end(em); 880 *defrag_end = 0; 881 } 882 883 free_extent_map(em); 884 return ret; 885 } 886 887 /* 888 * it doesn't do much good to defrag one or two pages 889 * at a time. This pulls in a nice chunk of pages 890 * to COW and defrag. 891 * 892 * It also makes sure the delalloc code has enough 893 * dirty data to avoid making new small extents as part 894 * of the defrag 895 * 896 * It's a good idea to start RA on this range 897 * before calling this. 898 */ 899 static int cluster_pages_for_defrag(struct inode *inode, 900 struct page **pages, 901 unsigned long start_index, 902 int num_pages) 903 { 904 unsigned long file_end; 905 u64 isize = i_size_read(inode); 906 u64 page_start; 907 u64 page_end; 908 u64 page_cnt; 909 int ret; 910 int i; 911 int i_done; 912 struct btrfs_ordered_extent *ordered; 913 struct extent_state *cached_state = NULL; 914 struct extent_io_tree *tree; 915 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 916 917 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 918 if (!isize || start_index > file_end) 919 return 0; 920 921 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); 922 923 ret = btrfs_delalloc_reserve_space(inode, 924 page_cnt << PAGE_CACHE_SHIFT); 925 if (ret) 926 return ret; 927 i_done = 0; 928 tree = &BTRFS_I(inode)->io_tree; 929 930 /* step one, lock all the pages */ 931 for (i = 0; i < page_cnt; i++) { 932 struct page *page; 933 again: 934 page = find_or_create_page(inode->i_mapping, 935 start_index + i, mask); 936 if (!page) 937 break; 938 939 page_start = page_offset(page); 940 page_end = page_start + PAGE_CACHE_SIZE - 1; 941 while (1) { 942 lock_extent(tree, page_start, page_end); 943 ordered = btrfs_lookup_ordered_extent(inode, 944 page_start); 945 unlock_extent(tree, page_start, page_end); 946 if (!ordered) 947 break; 948 949 unlock_page(page); 950 btrfs_start_ordered_extent(inode, ordered, 1); 951 btrfs_put_ordered_extent(ordered); 952 lock_page(page); 953 /* 954 * we unlocked the page above, so we need check if 955 * it was released or not. 956 */ 957 if (page->mapping != inode->i_mapping) { 958 unlock_page(page); 959 page_cache_release(page); 960 goto again; 961 } 962 } 963 964 if (!PageUptodate(page)) { 965 btrfs_readpage(NULL, page); 966 lock_page(page); 967 if (!PageUptodate(page)) { 968 unlock_page(page); 969 page_cache_release(page); 970 ret = -EIO; 971 break; 972 } 973 } 974 975 if (page->mapping != inode->i_mapping) { 976 unlock_page(page); 977 page_cache_release(page); 978 goto again; 979 } 980 981 pages[i] = page; 982 i_done++; 983 } 984 if (!i_done || ret) 985 goto out; 986 987 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 988 goto out; 989 990 /* 991 * so now we have a nice long stream of locked 992 * and up to date pages, lets wait on them 993 */ 994 for (i = 0; i < i_done; i++) 995 wait_on_page_writeback(pages[i]); 996 997 page_start = page_offset(pages[0]); 998 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; 999 1000 lock_extent_bits(&BTRFS_I(inode)->io_tree, 1001 page_start, page_end - 1, 0, &cached_state); 1002 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 1003 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 1004 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state, 1005 GFP_NOFS); 1006 1007 if (i_done != page_cnt) { 1008 spin_lock(&BTRFS_I(inode)->lock); 1009 BTRFS_I(inode)->outstanding_extents++; 1010 spin_unlock(&BTRFS_I(inode)->lock); 1011 btrfs_delalloc_release_space(inode, 1012 (page_cnt - i_done) << PAGE_CACHE_SHIFT); 1013 } 1014 1015 1016 btrfs_set_extent_delalloc(inode, page_start, page_end - 1, 1017 &cached_state); 1018 1019 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 1020 page_start, page_end - 1, &cached_state, 1021 GFP_NOFS); 1022 1023 for (i = 0; i < i_done; i++) { 1024 clear_page_dirty_for_io(pages[i]); 1025 ClearPageChecked(pages[i]); 1026 set_page_extent_mapped(pages[i]); 1027 set_page_dirty(pages[i]); 1028 unlock_page(pages[i]); 1029 page_cache_release(pages[i]); 1030 } 1031 return i_done; 1032 out: 1033 for (i = 0; i < i_done; i++) { 1034 unlock_page(pages[i]); 1035 page_cache_release(pages[i]); 1036 } 1037 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT); 1038 return ret; 1039 1040 } 1041 1042 int btrfs_defrag_file(struct inode *inode, struct file *file, 1043 struct btrfs_ioctl_defrag_range_args *range, 1044 u64 newer_than, unsigned long max_to_defrag) 1045 { 1046 struct btrfs_root *root = BTRFS_I(inode)->root; 1047 struct btrfs_super_block *disk_super; 1048 struct file_ra_state *ra = NULL; 1049 unsigned long last_index; 1050 u64 isize = i_size_read(inode); 1051 u64 features; 1052 u64 last_len = 0; 1053 u64 skip = 0; 1054 u64 defrag_end = 0; 1055 u64 newer_off = range->start; 1056 unsigned long i; 1057 unsigned long ra_index = 0; 1058 int ret; 1059 int defrag_count = 0; 1060 int compress_type = BTRFS_COMPRESS_ZLIB; 1061 int extent_thresh = range->extent_thresh; 1062 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; 1063 int cluster = max_cluster; 1064 u64 new_align = ~((u64)128 * 1024 - 1); 1065 struct page **pages = NULL; 1066 1067 if (extent_thresh == 0) 1068 extent_thresh = 256 * 1024; 1069 1070 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1071 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1072 return -EINVAL; 1073 if (range->compress_type) 1074 compress_type = range->compress_type; 1075 } 1076 1077 if (isize == 0) 1078 return 0; 1079 1080 /* 1081 * if we were not given a file, allocate a readahead 1082 * context 1083 */ 1084 if (!file) { 1085 ra = kzalloc(sizeof(*ra), GFP_NOFS); 1086 if (!ra) 1087 return -ENOMEM; 1088 file_ra_state_init(ra, inode->i_mapping); 1089 } else { 1090 ra = &file->f_ra; 1091 } 1092 1093 pages = kmalloc(sizeof(struct page *) * max_cluster, 1094 GFP_NOFS); 1095 if (!pages) { 1096 ret = -ENOMEM; 1097 goto out_ra; 1098 } 1099 1100 /* find the last page to defrag */ 1101 if (range->start + range->len > range->start) { 1102 last_index = min_t(u64, isize - 1, 1103 range->start + range->len - 1) >> PAGE_CACHE_SHIFT; 1104 } else { 1105 last_index = (isize - 1) >> PAGE_CACHE_SHIFT; 1106 } 1107 1108 if (newer_than) { 1109 ret = find_new_extents(root, inode, newer_than, 1110 &newer_off, 64 * 1024); 1111 if (!ret) { 1112 range->start = newer_off; 1113 /* 1114 * we always align our defrag to help keep 1115 * the extents in the file evenly spaced 1116 */ 1117 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1118 } else 1119 goto out_ra; 1120 } else { 1121 i = range->start >> PAGE_CACHE_SHIFT; 1122 } 1123 if (!max_to_defrag) 1124 max_to_defrag = last_index + 1; 1125 1126 /* 1127 * make writeback starts from i, so the defrag range can be 1128 * written sequentially. 1129 */ 1130 if (i < inode->i_mapping->writeback_index) 1131 inode->i_mapping->writeback_index = i; 1132 1133 while (i <= last_index && defrag_count < max_to_defrag && 1134 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> 1135 PAGE_CACHE_SHIFT)) { 1136 /* 1137 * make sure we stop running if someone unmounts 1138 * the FS 1139 */ 1140 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1141 break; 1142 1143 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, 1144 PAGE_CACHE_SIZE, extent_thresh, 1145 &last_len, &skip, &defrag_end)) { 1146 unsigned long next; 1147 /* 1148 * the should_defrag function tells us how much to skip 1149 * bump our counter by the suggested amount 1150 */ 1151 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 1152 i = max(i + 1, next); 1153 continue; 1154 } 1155 1156 if (!newer_than) { 1157 cluster = (PAGE_CACHE_ALIGN(defrag_end) >> 1158 PAGE_CACHE_SHIFT) - i; 1159 cluster = min(cluster, max_cluster); 1160 } else { 1161 cluster = max_cluster; 1162 } 1163 1164 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) 1165 BTRFS_I(inode)->force_compress = compress_type; 1166 1167 if (i + cluster > ra_index) { 1168 ra_index = max(i, ra_index); 1169 btrfs_force_ra(inode->i_mapping, ra, file, ra_index, 1170 cluster); 1171 ra_index += max_cluster; 1172 } 1173 1174 mutex_lock(&inode->i_mutex); 1175 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1176 if (ret < 0) { 1177 mutex_unlock(&inode->i_mutex); 1178 goto out_ra; 1179 } 1180 1181 defrag_count += ret; 1182 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret); 1183 mutex_unlock(&inode->i_mutex); 1184 1185 if (newer_than) { 1186 if (newer_off == (u64)-1) 1187 break; 1188 1189 if (ret > 0) 1190 i += ret; 1191 1192 newer_off = max(newer_off + 1, 1193 (u64)i << PAGE_CACHE_SHIFT); 1194 1195 ret = find_new_extents(root, inode, 1196 newer_than, &newer_off, 1197 64 * 1024); 1198 if (!ret) { 1199 range->start = newer_off; 1200 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1201 } else { 1202 break; 1203 } 1204 } else { 1205 if (ret > 0) { 1206 i += ret; 1207 last_len += ret << PAGE_CACHE_SHIFT; 1208 } else { 1209 i++; 1210 last_len = 0; 1211 } 1212 } 1213 } 1214 1215 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) 1216 filemap_flush(inode->i_mapping); 1217 1218 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 1219 /* the filemap_flush will queue IO into the worker threads, but 1220 * we have to make sure the IO is actually started and that 1221 * ordered extents get created before we return 1222 */ 1223 atomic_inc(&root->fs_info->async_submit_draining); 1224 while (atomic_read(&root->fs_info->nr_async_submits) || 1225 atomic_read(&root->fs_info->async_delalloc_pages)) { 1226 wait_event(root->fs_info->async_submit_wait, 1227 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 1228 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 1229 } 1230 atomic_dec(&root->fs_info->async_submit_draining); 1231 1232 mutex_lock(&inode->i_mutex); 1233 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; 1234 mutex_unlock(&inode->i_mutex); 1235 } 1236 1237 disk_super = root->fs_info->super_copy; 1238 features = btrfs_super_incompat_flags(disk_super); 1239 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1240 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO; 1241 btrfs_set_super_incompat_flags(disk_super, features); 1242 } 1243 1244 ret = defrag_count; 1245 1246 out_ra: 1247 if (!file) 1248 kfree(ra); 1249 kfree(pages); 1250 return ret; 1251 } 1252 1253 static noinline int btrfs_ioctl_resize(struct btrfs_root *root, 1254 void __user *arg) 1255 { 1256 u64 new_size; 1257 u64 old_size; 1258 u64 devid = 1; 1259 struct btrfs_ioctl_vol_args *vol_args; 1260 struct btrfs_trans_handle *trans; 1261 struct btrfs_device *device = NULL; 1262 char *sizestr; 1263 char *devstr = NULL; 1264 int ret = 0; 1265 int mod = 0; 1266 1267 if (root->fs_info->sb->s_flags & MS_RDONLY) 1268 return -EROFS; 1269 1270 if (!capable(CAP_SYS_ADMIN)) 1271 return -EPERM; 1272 1273 mutex_lock(&root->fs_info->volume_mutex); 1274 if (root->fs_info->balance_ctl) { 1275 printk(KERN_INFO "btrfs: balance in progress\n"); 1276 ret = -EINVAL; 1277 goto out; 1278 } 1279 1280 vol_args = memdup_user(arg, sizeof(*vol_args)); 1281 if (IS_ERR(vol_args)) { 1282 ret = PTR_ERR(vol_args); 1283 goto out; 1284 } 1285 1286 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1287 1288 sizestr = vol_args->name; 1289 devstr = strchr(sizestr, ':'); 1290 if (devstr) { 1291 char *end; 1292 sizestr = devstr + 1; 1293 *devstr = '\0'; 1294 devstr = vol_args->name; 1295 devid = simple_strtoull(devstr, &end, 10); 1296 printk(KERN_INFO "btrfs: resizing devid %llu\n", 1297 (unsigned long long)devid); 1298 } 1299 device = btrfs_find_device(root, devid, NULL, NULL); 1300 if (!device) { 1301 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n", 1302 (unsigned long long)devid); 1303 ret = -EINVAL; 1304 goto out_free; 1305 } 1306 if (!strcmp(sizestr, "max")) 1307 new_size = device->bdev->bd_inode->i_size; 1308 else { 1309 if (sizestr[0] == '-') { 1310 mod = -1; 1311 sizestr++; 1312 } else if (sizestr[0] == '+') { 1313 mod = 1; 1314 sizestr++; 1315 } 1316 new_size = memparse(sizestr, NULL); 1317 if (new_size == 0) { 1318 ret = -EINVAL; 1319 goto out_free; 1320 } 1321 } 1322 1323 old_size = device->total_bytes; 1324 1325 if (mod < 0) { 1326 if (new_size > old_size) { 1327 ret = -EINVAL; 1328 goto out_free; 1329 } 1330 new_size = old_size - new_size; 1331 } else if (mod > 0) { 1332 new_size = old_size + new_size; 1333 } 1334 1335 if (new_size < 256 * 1024 * 1024) { 1336 ret = -EINVAL; 1337 goto out_free; 1338 } 1339 if (new_size > device->bdev->bd_inode->i_size) { 1340 ret = -EFBIG; 1341 goto out_free; 1342 } 1343 1344 do_div(new_size, root->sectorsize); 1345 new_size *= root->sectorsize; 1346 1347 printk(KERN_INFO "btrfs: new size for %s is %llu\n", 1348 device->name, (unsigned long long)new_size); 1349 1350 if (new_size > old_size) { 1351 trans = btrfs_start_transaction(root, 0); 1352 if (IS_ERR(trans)) { 1353 ret = PTR_ERR(trans); 1354 goto out_free; 1355 } 1356 ret = btrfs_grow_device(trans, device, new_size); 1357 btrfs_commit_transaction(trans, root); 1358 } else if (new_size < old_size) { 1359 ret = btrfs_shrink_device(device, new_size); 1360 } 1361 1362 out_free: 1363 kfree(vol_args); 1364 out: 1365 mutex_unlock(&root->fs_info->volume_mutex); 1366 return ret; 1367 } 1368 1369 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1370 char *name, 1371 unsigned long fd, 1372 int subvol, 1373 u64 *transid, 1374 bool readonly) 1375 { 1376 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 1377 struct file *src_file; 1378 int namelen; 1379 int ret = 0; 1380 1381 if (root->fs_info->sb->s_flags & MS_RDONLY) 1382 return -EROFS; 1383 1384 namelen = strlen(name); 1385 if (strchr(name, '/')) { 1386 ret = -EINVAL; 1387 goto out; 1388 } 1389 1390 if (name[0] == '.' && 1391 (namelen == 1 || (name[1] == '.' && namelen == 2))) { 1392 ret = -EEXIST; 1393 goto out; 1394 } 1395 1396 if (subvol) { 1397 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1398 NULL, transid, readonly); 1399 } else { 1400 struct inode *src_inode; 1401 src_file = fget(fd); 1402 if (!src_file) { 1403 ret = -EINVAL; 1404 goto out; 1405 } 1406 1407 src_inode = src_file->f_path.dentry->d_inode; 1408 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { 1409 printk(KERN_INFO "btrfs: Snapshot src from " 1410 "another FS\n"); 1411 ret = -EINVAL; 1412 fput(src_file); 1413 goto out; 1414 } 1415 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1416 BTRFS_I(src_inode)->root, 1417 transid, readonly); 1418 fput(src_file); 1419 } 1420 out: 1421 return ret; 1422 } 1423 1424 static noinline int btrfs_ioctl_snap_create(struct file *file, 1425 void __user *arg, int subvol) 1426 { 1427 struct btrfs_ioctl_vol_args *vol_args; 1428 int ret; 1429 1430 vol_args = memdup_user(arg, sizeof(*vol_args)); 1431 if (IS_ERR(vol_args)) 1432 return PTR_ERR(vol_args); 1433 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1434 1435 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1436 vol_args->fd, subvol, 1437 NULL, false); 1438 1439 kfree(vol_args); 1440 return ret; 1441 } 1442 1443 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1444 void __user *arg, int subvol) 1445 { 1446 struct btrfs_ioctl_vol_args_v2 *vol_args; 1447 int ret; 1448 u64 transid = 0; 1449 u64 *ptr = NULL; 1450 bool readonly = false; 1451 1452 vol_args = memdup_user(arg, sizeof(*vol_args)); 1453 if (IS_ERR(vol_args)) 1454 return PTR_ERR(vol_args); 1455 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1456 1457 if (vol_args->flags & 1458 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) { 1459 ret = -EOPNOTSUPP; 1460 goto out; 1461 } 1462 1463 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1464 ptr = &transid; 1465 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1466 readonly = true; 1467 1468 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1469 vol_args->fd, subvol, 1470 ptr, readonly); 1471 1472 if (ret == 0 && ptr && 1473 copy_to_user(arg + 1474 offsetof(struct btrfs_ioctl_vol_args_v2, 1475 transid), ptr, sizeof(*ptr))) 1476 ret = -EFAULT; 1477 out: 1478 kfree(vol_args); 1479 return ret; 1480 } 1481 1482 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1483 void __user *arg) 1484 { 1485 struct inode *inode = fdentry(file)->d_inode; 1486 struct btrfs_root *root = BTRFS_I(inode)->root; 1487 int ret = 0; 1488 u64 flags = 0; 1489 1490 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1491 return -EINVAL; 1492 1493 down_read(&root->fs_info->subvol_sem); 1494 if (btrfs_root_readonly(root)) 1495 flags |= BTRFS_SUBVOL_RDONLY; 1496 up_read(&root->fs_info->subvol_sem); 1497 1498 if (copy_to_user(arg, &flags, sizeof(flags))) 1499 ret = -EFAULT; 1500 1501 return ret; 1502 } 1503 1504 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1505 void __user *arg) 1506 { 1507 struct inode *inode = fdentry(file)->d_inode; 1508 struct btrfs_root *root = BTRFS_I(inode)->root; 1509 struct btrfs_trans_handle *trans; 1510 u64 root_flags; 1511 u64 flags; 1512 int ret = 0; 1513 1514 if (root->fs_info->sb->s_flags & MS_RDONLY) 1515 return -EROFS; 1516 1517 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1518 return -EINVAL; 1519 1520 if (copy_from_user(&flags, arg, sizeof(flags))) 1521 return -EFAULT; 1522 1523 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) 1524 return -EINVAL; 1525 1526 if (flags & ~BTRFS_SUBVOL_RDONLY) 1527 return -EOPNOTSUPP; 1528 1529 if (!inode_owner_or_capable(inode)) 1530 return -EACCES; 1531 1532 down_write(&root->fs_info->subvol_sem); 1533 1534 /* nothing to do */ 1535 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1536 goto out; 1537 1538 root_flags = btrfs_root_flags(&root->root_item); 1539 if (flags & BTRFS_SUBVOL_RDONLY) 1540 btrfs_set_root_flags(&root->root_item, 1541 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1542 else 1543 btrfs_set_root_flags(&root->root_item, 1544 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1545 1546 trans = btrfs_start_transaction(root, 1); 1547 if (IS_ERR(trans)) { 1548 ret = PTR_ERR(trans); 1549 goto out_reset; 1550 } 1551 1552 ret = btrfs_update_root(trans, root->fs_info->tree_root, 1553 &root->root_key, &root->root_item); 1554 1555 btrfs_commit_transaction(trans, root); 1556 out_reset: 1557 if (ret) 1558 btrfs_set_root_flags(&root->root_item, root_flags); 1559 out: 1560 up_write(&root->fs_info->subvol_sem); 1561 return ret; 1562 } 1563 1564 /* 1565 * helper to check if the subvolume references other subvolumes 1566 */ 1567 static noinline int may_destroy_subvol(struct btrfs_root *root) 1568 { 1569 struct btrfs_path *path; 1570 struct btrfs_key key; 1571 int ret; 1572 1573 path = btrfs_alloc_path(); 1574 if (!path) 1575 return -ENOMEM; 1576 1577 key.objectid = root->root_key.objectid; 1578 key.type = BTRFS_ROOT_REF_KEY; 1579 key.offset = (u64)-1; 1580 1581 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, 1582 &key, path, 0, 0); 1583 if (ret < 0) 1584 goto out; 1585 BUG_ON(ret == 0); 1586 1587 ret = 0; 1588 if (path->slots[0] > 0) { 1589 path->slots[0]--; 1590 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 1591 if (key.objectid == root->root_key.objectid && 1592 key.type == BTRFS_ROOT_REF_KEY) 1593 ret = -ENOTEMPTY; 1594 } 1595 out: 1596 btrfs_free_path(path); 1597 return ret; 1598 } 1599 1600 static noinline int key_in_sk(struct btrfs_key *key, 1601 struct btrfs_ioctl_search_key *sk) 1602 { 1603 struct btrfs_key test; 1604 int ret; 1605 1606 test.objectid = sk->min_objectid; 1607 test.type = sk->min_type; 1608 test.offset = sk->min_offset; 1609 1610 ret = btrfs_comp_cpu_keys(key, &test); 1611 if (ret < 0) 1612 return 0; 1613 1614 test.objectid = sk->max_objectid; 1615 test.type = sk->max_type; 1616 test.offset = sk->max_offset; 1617 1618 ret = btrfs_comp_cpu_keys(key, &test); 1619 if (ret > 0) 1620 return 0; 1621 return 1; 1622 } 1623 1624 static noinline int copy_to_sk(struct btrfs_root *root, 1625 struct btrfs_path *path, 1626 struct btrfs_key *key, 1627 struct btrfs_ioctl_search_key *sk, 1628 char *buf, 1629 unsigned long *sk_offset, 1630 int *num_found) 1631 { 1632 u64 found_transid; 1633 struct extent_buffer *leaf; 1634 struct btrfs_ioctl_search_header sh; 1635 unsigned long item_off; 1636 unsigned long item_len; 1637 int nritems; 1638 int i; 1639 int slot; 1640 int ret = 0; 1641 1642 leaf = path->nodes[0]; 1643 slot = path->slots[0]; 1644 nritems = btrfs_header_nritems(leaf); 1645 1646 if (btrfs_header_generation(leaf) > sk->max_transid) { 1647 i = nritems; 1648 goto advance_key; 1649 } 1650 found_transid = btrfs_header_generation(leaf); 1651 1652 for (i = slot; i < nritems; i++) { 1653 item_off = btrfs_item_ptr_offset(leaf, i); 1654 item_len = btrfs_item_size_nr(leaf, i); 1655 1656 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) 1657 item_len = 0; 1658 1659 if (sizeof(sh) + item_len + *sk_offset > 1660 BTRFS_SEARCH_ARGS_BUFSIZE) { 1661 ret = 1; 1662 goto overflow; 1663 } 1664 1665 btrfs_item_key_to_cpu(leaf, key, i); 1666 if (!key_in_sk(key, sk)) 1667 continue; 1668 1669 sh.objectid = key->objectid; 1670 sh.offset = key->offset; 1671 sh.type = key->type; 1672 sh.len = item_len; 1673 sh.transid = found_transid; 1674 1675 /* copy search result header */ 1676 memcpy(buf + *sk_offset, &sh, sizeof(sh)); 1677 *sk_offset += sizeof(sh); 1678 1679 if (item_len) { 1680 char *p = buf + *sk_offset; 1681 /* copy the item */ 1682 read_extent_buffer(leaf, p, 1683 item_off, item_len); 1684 *sk_offset += item_len; 1685 } 1686 (*num_found)++; 1687 1688 if (*num_found >= sk->nr_items) 1689 break; 1690 } 1691 advance_key: 1692 ret = 0; 1693 if (key->offset < (u64)-1 && key->offset < sk->max_offset) 1694 key->offset++; 1695 else if (key->type < (u8)-1 && key->type < sk->max_type) { 1696 key->offset = 0; 1697 key->type++; 1698 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { 1699 key->offset = 0; 1700 key->type = 0; 1701 key->objectid++; 1702 } else 1703 ret = 1; 1704 overflow: 1705 return ret; 1706 } 1707 1708 static noinline int search_ioctl(struct inode *inode, 1709 struct btrfs_ioctl_search_args *args) 1710 { 1711 struct btrfs_root *root; 1712 struct btrfs_key key; 1713 struct btrfs_key max_key; 1714 struct btrfs_path *path; 1715 struct btrfs_ioctl_search_key *sk = &args->key; 1716 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; 1717 int ret; 1718 int num_found = 0; 1719 unsigned long sk_offset = 0; 1720 1721 path = btrfs_alloc_path(); 1722 if (!path) 1723 return -ENOMEM; 1724 1725 if (sk->tree_id == 0) { 1726 /* search the root of the inode that was passed */ 1727 root = BTRFS_I(inode)->root; 1728 } else { 1729 key.objectid = sk->tree_id; 1730 key.type = BTRFS_ROOT_ITEM_KEY; 1731 key.offset = (u64)-1; 1732 root = btrfs_read_fs_root_no_name(info, &key); 1733 if (IS_ERR(root)) { 1734 printk(KERN_ERR "could not find root %llu\n", 1735 sk->tree_id); 1736 btrfs_free_path(path); 1737 return -ENOENT; 1738 } 1739 } 1740 1741 key.objectid = sk->min_objectid; 1742 key.type = sk->min_type; 1743 key.offset = sk->min_offset; 1744 1745 max_key.objectid = sk->max_objectid; 1746 max_key.type = sk->max_type; 1747 max_key.offset = sk->max_offset; 1748 1749 path->keep_locks = 1; 1750 1751 while(1) { 1752 ret = btrfs_search_forward(root, &key, &max_key, path, 0, 1753 sk->min_transid); 1754 if (ret != 0) { 1755 if (ret > 0) 1756 ret = 0; 1757 goto err; 1758 } 1759 ret = copy_to_sk(root, path, &key, sk, args->buf, 1760 &sk_offset, &num_found); 1761 btrfs_release_path(path); 1762 if (ret || num_found >= sk->nr_items) 1763 break; 1764 1765 } 1766 ret = 0; 1767 err: 1768 sk->nr_items = num_found; 1769 btrfs_free_path(path); 1770 return ret; 1771 } 1772 1773 static noinline int btrfs_ioctl_tree_search(struct file *file, 1774 void __user *argp) 1775 { 1776 struct btrfs_ioctl_search_args *args; 1777 struct inode *inode; 1778 int ret; 1779 1780 if (!capable(CAP_SYS_ADMIN)) 1781 return -EPERM; 1782 1783 args = memdup_user(argp, sizeof(*args)); 1784 if (IS_ERR(args)) 1785 return PTR_ERR(args); 1786 1787 inode = fdentry(file)->d_inode; 1788 ret = search_ioctl(inode, args); 1789 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1790 ret = -EFAULT; 1791 kfree(args); 1792 return ret; 1793 } 1794 1795 /* 1796 * Search INODE_REFs to identify path name of 'dirid' directory 1797 * in a 'tree_id' tree. and sets path name to 'name'. 1798 */ 1799 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 1800 u64 tree_id, u64 dirid, char *name) 1801 { 1802 struct btrfs_root *root; 1803 struct btrfs_key key; 1804 char *ptr; 1805 int ret = -1; 1806 int slot; 1807 int len; 1808 int total_len = 0; 1809 struct btrfs_inode_ref *iref; 1810 struct extent_buffer *l; 1811 struct btrfs_path *path; 1812 1813 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 1814 name[0]='\0'; 1815 return 0; 1816 } 1817 1818 path = btrfs_alloc_path(); 1819 if (!path) 1820 return -ENOMEM; 1821 1822 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; 1823 1824 key.objectid = tree_id; 1825 key.type = BTRFS_ROOT_ITEM_KEY; 1826 key.offset = (u64)-1; 1827 root = btrfs_read_fs_root_no_name(info, &key); 1828 if (IS_ERR(root)) { 1829 printk(KERN_ERR "could not find root %llu\n", tree_id); 1830 ret = -ENOENT; 1831 goto out; 1832 } 1833 1834 key.objectid = dirid; 1835 key.type = BTRFS_INODE_REF_KEY; 1836 key.offset = (u64)-1; 1837 1838 while(1) { 1839 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1840 if (ret < 0) 1841 goto out; 1842 1843 l = path->nodes[0]; 1844 slot = path->slots[0]; 1845 if (ret > 0 && slot > 0) 1846 slot--; 1847 btrfs_item_key_to_cpu(l, &key, slot); 1848 1849 if (ret > 0 && (key.objectid != dirid || 1850 key.type != BTRFS_INODE_REF_KEY)) { 1851 ret = -ENOENT; 1852 goto out; 1853 } 1854 1855 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 1856 len = btrfs_inode_ref_name_len(l, iref); 1857 ptr -= len + 1; 1858 total_len += len + 1; 1859 if (ptr < name) 1860 goto out; 1861 1862 *(ptr + len) = '/'; 1863 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len); 1864 1865 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 1866 break; 1867 1868 btrfs_release_path(path); 1869 key.objectid = key.offset; 1870 key.offset = (u64)-1; 1871 dirid = key.objectid; 1872 } 1873 if (ptr < name) 1874 goto out; 1875 memmove(name, ptr, total_len); 1876 name[total_len]='\0'; 1877 ret = 0; 1878 out: 1879 btrfs_free_path(path); 1880 return ret; 1881 } 1882 1883 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 1884 void __user *argp) 1885 { 1886 struct btrfs_ioctl_ino_lookup_args *args; 1887 struct inode *inode; 1888 int ret; 1889 1890 if (!capable(CAP_SYS_ADMIN)) 1891 return -EPERM; 1892 1893 args = memdup_user(argp, sizeof(*args)); 1894 if (IS_ERR(args)) 1895 return PTR_ERR(args); 1896 1897 inode = fdentry(file)->d_inode; 1898 1899 if (args->treeid == 0) 1900 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 1901 1902 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 1903 args->treeid, args->objectid, 1904 args->name); 1905 1906 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1907 ret = -EFAULT; 1908 1909 kfree(args); 1910 return ret; 1911 } 1912 1913 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 1914 void __user *arg) 1915 { 1916 struct dentry *parent = fdentry(file); 1917 struct dentry *dentry; 1918 struct inode *dir = parent->d_inode; 1919 struct inode *inode; 1920 struct btrfs_root *root = BTRFS_I(dir)->root; 1921 struct btrfs_root *dest = NULL; 1922 struct btrfs_ioctl_vol_args *vol_args; 1923 struct btrfs_trans_handle *trans; 1924 int namelen; 1925 int ret; 1926 int err = 0; 1927 1928 vol_args = memdup_user(arg, sizeof(*vol_args)); 1929 if (IS_ERR(vol_args)) 1930 return PTR_ERR(vol_args); 1931 1932 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1933 namelen = strlen(vol_args->name); 1934 if (strchr(vol_args->name, '/') || 1935 strncmp(vol_args->name, "..", namelen) == 0) { 1936 err = -EINVAL; 1937 goto out; 1938 } 1939 1940 err = mnt_want_write_file(file); 1941 if (err) 1942 goto out; 1943 1944 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 1945 dentry = lookup_one_len(vol_args->name, parent, namelen); 1946 if (IS_ERR(dentry)) { 1947 err = PTR_ERR(dentry); 1948 goto out_unlock_dir; 1949 } 1950 1951 if (!dentry->d_inode) { 1952 err = -ENOENT; 1953 goto out_dput; 1954 } 1955 1956 inode = dentry->d_inode; 1957 dest = BTRFS_I(inode)->root; 1958 if (!capable(CAP_SYS_ADMIN)){ 1959 /* 1960 * Regular user. Only allow this with a special mount 1961 * option, when the user has write+exec access to the 1962 * subvol root, and when rmdir(2) would have been 1963 * allowed. 1964 * 1965 * Note that this is _not_ check that the subvol is 1966 * empty or doesn't contain data that we wouldn't 1967 * otherwise be able to delete. 1968 * 1969 * Users who want to delete empty subvols should try 1970 * rmdir(2). 1971 */ 1972 err = -EPERM; 1973 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 1974 goto out_dput; 1975 1976 /* 1977 * Do not allow deletion if the parent dir is the same 1978 * as the dir to be deleted. That means the ioctl 1979 * must be called on the dentry referencing the root 1980 * of the subvol, not a random directory contained 1981 * within it. 1982 */ 1983 err = -EINVAL; 1984 if (root == dest) 1985 goto out_dput; 1986 1987 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 1988 if (err) 1989 goto out_dput; 1990 1991 /* check if subvolume may be deleted by a non-root user */ 1992 err = btrfs_may_delete(dir, dentry, 1); 1993 if (err) 1994 goto out_dput; 1995 } 1996 1997 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 1998 err = -EINVAL; 1999 goto out_dput; 2000 } 2001 2002 mutex_lock(&inode->i_mutex); 2003 err = d_invalidate(dentry); 2004 if (err) 2005 goto out_unlock; 2006 2007 down_write(&root->fs_info->subvol_sem); 2008 2009 err = may_destroy_subvol(dest); 2010 if (err) 2011 goto out_up_write; 2012 2013 trans = btrfs_start_transaction(root, 0); 2014 if (IS_ERR(trans)) { 2015 err = PTR_ERR(trans); 2016 goto out_up_write; 2017 } 2018 trans->block_rsv = &root->fs_info->global_block_rsv; 2019 2020 ret = btrfs_unlink_subvol(trans, root, dir, 2021 dest->root_key.objectid, 2022 dentry->d_name.name, 2023 dentry->d_name.len); 2024 if (ret) { 2025 err = ret; 2026 btrfs_abort_transaction(trans, root, ret); 2027 goto out_end_trans; 2028 } 2029 2030 btrfs_record_root_in_trans(trans, dest); 2031 2032 memset(&dest->root_item.drop_progress, 0, 2033 sizeof(dest->root_item.drop_progress)); 2034 dest->root_item.drop_level = 0; 2035 btrfs_set_root_refs(&dest->root_item, 0); 2036 2037 if (!xchg(&dest->orphan_item_inserted, 1)) { 2038 ret = btrfs_insert_orphan_item(trans, 2039 root->fs_info->tree_root, 2040 dest->root_key.objectid); 2041 if (ret) { 2042 btrfs_abort_transaction(trans, root, ret); 2043 err = ret; 2044 goto out_end_trans; 2045 } 2046 } 2047 out_end_trans: 2048 ret = btrfs_end_transaction(trans, root); 2049 if (ret && !err) 2050 err = ret; 2051 inode->i_flags |= S_DEAD; 2052 out_up_write: 2053 up_write(&root->fs_info->subvol_sem); 2054 out_unlock: 2055 mutex_unlock(&inode->i_mutex); 2056 if (!err) { 2057 shrink_dcache_sb(root->fs_info->sb); 2058 btrfs_invalidate_inodes(dest); 2059 d_delete(dentry); 2060 } 2061 out_dput: 2062 dput(dentry); 2063 out_unlock_dir: 2064 mutex_unlock(&dir->i_mutex); 2065 mnt_drop_write_file(file); 2066 out: 2067 kfree(vol_args); 2068 return err; 2069 } 2070 2071 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 2072 { 2073 struct inode *inode = fdentry(file)->d_inode; 2074 struct btrfs_root *root = BTRFS_I(inode)->root; 2075 struct btrfs_ioctl_defrag_range_args *range; 2076 int ret; 2077 2078 if (btrfs_root_readonly(root)) 2079 return -EROFS; 2080 2081 ret = mnt_want_write_file(file); 2082 if (ret) 2083 return ret; 2084 2085 switch (inode->i_mode & S_IFMT) { 2086 case S_IFDIR: 2087 if (!capable(CAP_SYS_ADMIN)) { 2088 ret = -EPERM; 2089 goto out; 2090 } 2091 ret = btrfs_defrag_root(root, 0); 2092 if (ret) 2093 goto out; 2094 ret = btrfs_defrag_root(root->fs_info->extent_root, 0); 2095 break; 2096 case S_IFREG: 2097 if (!(file->f_mode & FMODE_WRITE)) { 2098 ret = -EINVAL; 2099 goto out; 2100 } 2101 2102 range = kzalloc(sizeof(*range), GFP_KERNEL); 2103 if (!range) { 2104 ret = -ENOMEM; 2105 goto out; 2106 } 2107 2108 if (argp) { 2109 if (copy_from_user(range, argp, 2110 sizeof(*range))) { 2111 ret = -EFAULT; 2112 kfree(range); 2113 goto out; 2114 } 2115 /* compression requires us to start the IO */ 2116 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2117 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2118 range->extent_thresh = (u32)-1; 2119 } 2120 } else { 2121 /* the rest are all set to zero by kzalloc */ 2122 range->len = (u64)-1; 2123 } 2124 ret = btrfs_defrag_file(fdentry(file)->d_inode, file, 2125 range, 0, 0); 2126 if (ret > 0) 2127 ret = 0; 2128 kfree(range); 2129 break; 2130 default: 2131 ret = -EINVAL; 2132 } 2133 out: 2134 mnt_drop_write_file(file); 2135 return ret; 2136 } 2137 2138 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 2139 { 2140 struct btrfs_ioctl_vol_args *vol_args; 2141 int ret; 2142 2143 if (!capable(CAP_SYS_ADMIN)) 2144 return -EPERM; 2145 2146 mutex_lock(&root->fs_info->volume_mutex); 2147 if (root->fs_info->balance_ctl) { 2148 printk(KERN_INFO "btrfs: balance in progress\n"); 2149 ret = -EINVAL; 2150 goto out; 2151 } 2152 2153 vol_args = memdup_user(arg, sizeof(*vol_args)); 2154 if (IS_ERR(vol_args)) { 2155 ret = PTR_ERR(vol_args); 2156 goto out; 2157 } 2158 2159 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2160 ret = btrfs_init_new_device(root, vol_args->name); 2161 2162 kfree(vol_args); 2163 out: 2164 mutex_unlock(&root->fs_info->volume_mutex); 2165 return ret; 2166 } 2167 2168 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) 2169 { 2170 struct btrfs_ioctl_vol_args *vol_args; 2171 int ret; 2172 2173 if (!capable(CAP_SYS_ADMIN)) 2174 return -EPERM; 2175 2176 if (root->fs_info->sb->s_flags & MS_RDONLY) 2177 return -EROFS; 2178 2179 mutex_lock(&root->fs_info->volume_mutex); 2180 if (root->fs_info->balance_ctl) { 2181 printk(KERN_INFO "btrfs: balance in progress\n"); 2182 ret = -EINVAL; 2183 goto out; 2184 } 2185 2186 vol_args = memdup_user(arg, sizeof(*vol_args)); 2187 if (IS_ERR(vol_args)) { 2188 ret = PTR_ERR(vol_args); 2189 goto out; 2190 } 2191 2192 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2193 ret = btrfs_rm_device(root, vol_args->name); 2194 2195 kfree(vol_args); 2196 out: 2197 mutex_unlock(&root->fs_info->volume_mutex); 2198 return ret; 2199 } 2200 2201 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) 2202 { 2203 struct btrfs_ioctl_fs_info_args *fi_args; 2204 struct btrfs_device *device; 2205 struct btrfs_device *next; 2206 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2207 int ret = 0; 2208 2209 if (!capable(CAP_SYS_ADMIN)) 2210 return -EPERM; 2211 2212 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 2213 if (!fi_args) 2214 return -ENOMEM; 2215 2216 fi_args->num_devices = fs_devices->num_devices; 2217 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); 2218 2219 mutex_lock(&fs_devices->device_list_mutex); 2220 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 2221 if (device->devid > fi_args->max_id) 2222 fi_args->max_id = device->devid; 2223 } 2224 mutex_unlock(&fs_devices->device_list_mutex); 2225 2226 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 2227 ret = -EFAULT; 2228 2229 kfree(fi_args); 2230 return ret; 2231 } 2232 2233 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) 2234 { 2235 struct btrfs_ioctl_dev_info_args *di_args; 2236 struct btrfs_device *dev; 2237 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2238 int ret = 0; 2239 char *s_uuid = NULL; 2240 char empty_uuid[BTRFS_UUID_SIZE] = {0}; 2241 2242 if (!capable(CAP_SYS_ADMIN)) 2243 return -EPERM; 2244 2245 di_args = memdup_user(arg, sizeof(*di_args)); 2246 if (IS_ERR(di_args)) 2247 return PTR_ERR(di_args); 2248 2249 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0) 2250 s_uuid = di_args->uuid; 2251 2252 mutex_lock(&fs_devices->device_list_mutex); 2253 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL); 2254 mutex_unlock(&fs_devices->device_list_mutex); 2255 2256 if (!dev) { 2257 ret = -ENODEV; 2258 goto out; 2259 } 2260 2261 di_args->devid = dev->devid; 2262 di_args->bytes_used = dev->bytes_used; 2263 di_args->total_bytes = dev->total_bytes; 2264 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 2265 if (dev->name) 2266 strncpy(di_args->path, dev->name, sizeof(di_args->path)); 2267 else 2268 di_args->path[0] = '\0'; 2269 2270 out: 2271 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 2272 ret = -EFAULT; 2273 2274 kfree(di_args); 2275 return ret; 2276 } 2277 2278 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 2279 u64 off, u64 olen, u64 destoff) 2280 { 2281 struct inode *inode = fdentry(file)->d_inode; 2282 struct btrfs_root *root = BTRFS_I(inode)->root; 2283 struct file *src_file; 2284 struct inode *src; 2285 struct btrfs_trans_handle *trans; 2286 struct btrfs_path *path; 2287 struct extent_buffer *leaf; 2288 char *buf; 2289 struct btrfs_key key; 2290 u32 nritems; 2291 int slot; 2292 int ret; 2293 u64 len = olen; 2294 u64 bs = root->fs_info->sb->s_blocksize; 2295 u64 hint_byte; 2296 2297 /* 2298 * TODO: 2299 * - split compressed inline extents. annoying: we need to 2300 * decompress into destination's address_space (the file offset 2301 * may change, so source mapping won't do), then recompress (or 2302 * otherwise reinsert) a subrange. 2303 * - allow ranges within the same file to be cloned (provided 2304 * they don't overlap)? 2305 */ 2306 2307 /* the destination must be opened for writing */ 2308 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) 2309 return -EINVAL; 2310 2311 if (btrfs_root_readonly(root)) 2312 return -EROFS; 2313 2314 ret = mnt_want_write_file(file); 2315 if (ret) 2316 return ret; 2317 2318 src_file = fget(srcfd); 2319 if (!src_file) { 2320 ret = -EBADF; 2321 goto out_drop_write; 2322 } 2323 2324 src = src_file->f_dentry->d_inode; 2325 2326 ret = -EINVAL; 2327 if (src == inode) 2328 goto out_fput; 2329 2330 /* the src must be open for reading */ 2331 if (!(src_file->f_mode & FMODE_READ)) 2332 goto out_fput; 2333 2334 /* don't make the dst file partly checksummed */ 2335 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 2336 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) 2337 goto out_fput; 2338 2339 ret = -EISDIR; 2340 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 2341 goto out_fput; 2342 2343 ret = -EXDEV; 2344 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root) 2345 goto out_fput; 2346 2347 ret = -ENOMEM; 2348 buf = vmalloc(btrfs_level_size(root, 0)); 2349 if (!buf) 2350 goto out_fput; 2351 2352 path = btrfs_alloc_path(); 2353 if (!path) { 2354 vfree(buf); 2355 goto out_fput; 2356 } 2357 path->reada = 2; 2358 2359 if (inode < src) { 2360 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); 2361 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); 2362 } else { 2363 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); 2364 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); 2365 } 2366 2367 /* determine range to clone */ 2368 ret = -EINVAL; 2369 if (off + len > src->i_size || off + len < off) 2370 goto out_unlock; 2371 if (len == 0) 2372 olen = len = src->i_size - off; 2373 /* if we extend to eof, continue to block boundary */ 2374 if (off + len == src->i_size) 2375 len = ALIGN(src->i_size, bs) - off; 2376 2377 /* verify the end result is block aligned */ 2378 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || 2379 !IS_ALIGNED(destoff, bs)) 2380 goto out_unlock; 2381 2382 if (destoff > inode->i_size) { 2383 ret = btrfs_cont_expand(inode, inode->i_size, destoff); 2384 if (ret) 2385 goto out_unlock; 2386 } 2387 2388 /* truncate page cache pages from target inode range */ 2389 truncate_inode_pages_range(&inode->i_data, destoff, 2390 PAGE_CACHE_ALIGN(destoff + len) - 1); 2391 2392 /* do any pending delalloc/csum calc on src, one way or 2393 another, and lock file content */ 2394 while (1) { 2395 struct btrfs_ordered_extent *ordered; 2396 lock_extent(&BTRFS_I(src)->io_tree, off, off+len); 2397 ordered = btrfs_lookup_first_ordered_extent(src, off+len); 2398 if (!ordered && 2399 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len, 2400 EXTENT_DELALLOC, 0, NULL)) 2401 break; 2402 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len); 2403 if (ordered) 2404 btrfs_put_ordered_extent(ordered); 2405 btrfs_wait_ordered_range(src, off, len); 2406 } 2407 2408 /* clone data */ 2409 key.objectid = btrfs_ino(src); 2410 key.type = BTRFS_EXTENT_DATA_KEY; 2411 key.offset = 0; 2412 2413 while (1) { 2414 /* 2415 * note the key will change type as we walk through the 2416 * tree. 2417 */ 2418 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2419 if (ret < 0) 2420 goto out; 2421 2422 nritems = btrfs_header_nritems(path->nodes[0]); 2423 if (path->slots[0] >= nritems) { 2424 ret = btrfs_next_leaf(root, path); 2425 if (ret < 0) 2426 goto out; 2427 if (ret > 0) 2428 break; 2429 nritems = btrfs_header_nritems(path->nodes[0]); 2430 } 2431 leaf = path->nodes[0]; 2432 slot = path->slots[0]; 2433 2434 btrfs_item_key_to_cpu(leaf, &key, slot); 2435 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || 2436 key.objectid != btrfs_ino(src)) 2437 break; 2438 2439 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { 2440 struct btrfs_file_extent_item *extent; 2441 int type; 2442 u32 size; 2443 struct btrfs_key new_key; 2444 u64 disko = 0, diskl = 0; 2445 u64 datao = 0, datal = 0; 2446 u8 comp; 2447 u64 endoff; 2448 2449 size = btrfs_item_size_nr(leaf, slot); 2450 read_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 comp = btrfs_file_extent_compression(leaf, extent); 2457 type = btrfs_file_extent_type(leaf, extent); 2458 if (type == BTRFS_FILE_EXTENT_REG || 2459 type == BTRFS_FILE_EXTENT_PREALLOC) { 2460 disko = btrfs_file_extent_disk_bytenr(leaf, 2461 extent); 2462 diskl = btrfs_file_extent_disk_num_bytes(leaf, 2463 extent); 2464 datao = btrfs_file_extent_offset(leaf, extent); 2465 datal = btrfs_file_extent_num_bytes(leaf, 2466 extent); 2467 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2468 /* take upper bound, may be compressed */ 2469 datal = btrfs_file_extent_ram_bytes(leaf, 2470 extent); 2471 } 2472 btrfs_release_path(path); 2473 2474 if (key.offset + datal <= off || 2475 key.offset >= off+len) 2476 goto next; 2477 2478 memcpy(&new_key, &key, sizeof(new_key)); 2479 new_key.objectid = btrfs_ino(inode); 2480 if (off <= key.offset) 2481 new_key.offset = key.offset + destoff - off; 2482 else 2483 new_key.offset = destoff; 2484 2485 /* 2486 * 1 - adjusting old extent (we may have to split it) 2487 * 1 - add new extent 2488 * 1 - inode update 2489 */ 2490 trans = btrfs_start_transaction(root, 3); 2491 if (IS_ERR(trans)) { 2492 ret = PTR_ERR(trans); 2493 goto out; 2494 } 2495 2496 if (type == BTRFS_FILE_EXTENT_REG || 2497 type == BTRFS_FILE_EXTENT_PREALLOC) { 2498 /* 2499 * a | --- range to clone ---| b 2500 * | ------------- extent ------------- | 2501 */ 2502 2503 /* substract range b */ 2504 if (key.offset + datal > off + len) 2505 datal = off + len - key.offset; 2506 2507 /* substract range a */ 2508 if (off > key.offset) { 2509 datao += off - key.offset; 2510 datal -= off - key.offset; 2511 } 2512 2513 ret = btrfs_drop_extents(trans, inode, 2514 new_key.offset, 2515 new_key.offset + datal, 2516 &hint_byte, 1); 2517 if (ret) { 2518 btrfs_abort_transaction(trans, root, 2519 ret); 2520 btrfs_end_transaction(trans, root); 2521 goto out; 2522 } 2523 2524 ret = btrfs_insert_empty_item(trans, root, path, 2525 &new_key, size); 2526 if (ret) { 2527 btrfs_abort_transaction(trans, root, 2528 ret); 2529 btrfs_end_transaction(trans, root); 2530 goto out; 2531 } 2532 2533 leaf = path->nodes[0]; 2534 slot = path->slots[0]; 2535 write_extent_buffer(leaf, buf, 2536 btrfs_item_ptr_offset(leaf, slot), 2537 size); 2538 2539 extent = btrfs_item_ptr(leaf, slot, 2540 struct btrfs_file_extent_item); 2541 2542 /* disko == 0 means it's a hole */ 2543 if (!disko) 2544 datao = 0; 2545 2546 btrfs_set_file_extent_offset(leaf, extent, 2547 datao); 2548 btrfs_set_file_extent_num_bytes(leaf, extent, 2549 datal); 2550 if (disko) { 2551 inode_add_bytes(inode, datal); 2552 ret = btrfs_inc_extent_ref(trans, root, 2553 disko, diskl, 0, 2554 root->root_key.objectid, 2555 btrfs_ino(inode), 2556 new_key.offset - datao, 2557 0); 2558 if (ret) { 2559 btrfs_abort_transaction(trans, 2560 root, 2561 ret); 2562 btrfs_end_transaction(trans, 2563 root); 2564 goto out; 2565 2566 } 2567 } 2568 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2569 u64 skip = 0; 2570 u64 trim = 0; 2571 if (off > key.offset) { 2572 skip = off - key.offset; 2573 new_key.offset += skip; 2574 } 2575 2576 if (key.offset + datal > off+len) 2577 trim = key.offset + datal - (off+len); 2578 2579 if (comp && (skip || trim)) { 2580 ret = -EINVAL; 2581 btrfs_end_transaction(trans, root); 2582 goto out; 2583 } 2584 size -= skip + trim; 2585 datal -= skip + trim; 2586 2587 ret = btrfs_drop_extents(trans, inode, 2588 new_key.offset, 2589 new_key.offset + datal, 2590 &hint_byte, 1); 2591 if (ret) { 2592 btrfs_abort_transaction(trans, root, 2593 ret); 2594 btrfs_end_transaction(trans, root); 2595 goto out; 2596 } 2597 2598 ret = btrfs_insert_empty_item(trans, root, path, 2599 &new_key, size); 2600 if (ret) { 2601 btrfs_abort_transaction(trans, root, 2602 ret); 2603 btrfs_end_transaction(trans, root); 2604 goto out; 2605 } 2606 2607 if (skip) { 2608 u32 start = 2609 btrfs_file_extent_calc_inline_size(0); 2610 memmove(buf+start, buf+start+skip, 2611 datal); 2612 } 2613 2614 leaf = path->nodes[0]; 2615 slot = path->slots[0]; 2616 write_extent_buffer(leaf, buf, 2617 btrfs_item_ptr_offset(leaf, slot), 2618 size); 2619 inode_add_bytes(inode, datal); 2620 } 2621 2622 btrfs_mark_buffer_dirty(leaf); 2623 btrfs_release_path(path); 2624 2625 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 2626 2627 /* 2628 * we round up to the block size at eof when 2629 * determining which extents to clone above, 2630 * but shouldn't round up the file size 2631 */ 2632 endoff = new_key.offset + datal; 2633 if (endoff > destoff+olen) 2634 endoff = destoff+olen; 2635 if (endoff > inode->i_size) 2636 btrfs_i_size_write(inode, endoff); 2637 2638 ret = btrfs_update_inode(trans, root, inode); 2639 if (ret) { 2640 btrfs_abort_transaction(trans, root, ret); 2641 btrfs_end_transaction(trans, root); 2642 goto out; 2643 } 2644 ret = btrfs_end_transaction(trans, root); 2645 } 2646 next: 2647 btrfs_release_path(path); 2648 key.offset++; 2649 } 2650 ret = 0; 2651 out: 2652 btrfs_release_path(path); 2653 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len); 2654 out_unlock: 2655 mutex_unlock(&src->i_mutex); 2656 mutex_unlock(&inode->i_mutex); 2657 vfree(buf); 2658 btrfs_free_path(path); 2659 out_fput: 2660 fput(src_file); 2661 out_drop_write: 2662 mnt_drop_write_file(file); 2663 return ret; 2664 } 2665 2666 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) 2667 { 2668 struct btrfs_ioctl_clone_range_args args; 2669 2670 if (copy_from_user(&args, argp, sizeof(args))) 2671 return -EFAULT; 2672 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, 2673 args.src_length, args.dest_offset); 2674 } 2675 2676 /* 2677 * there are many ways the trans_start and trans_end ioctls can lead 2678 * to deadlocks. They should only be used by applications that 2679 * basically own the machine, and have a very in depth understanding 2680 * of all the possible deadlocks and enospc problems. 2681 */ 2682 static long btrfs_ioctl_trans_start(struct file *file) 2683 { 2684 struct inode *inode = fdentry(file)->d_inode; 2685 struct btrfs_root *root = BTRFS_I(inode)->root; 2686 struct btrfs_trans_handle *trans; 2687 int ret; 2688 2689 ret = -EPERM; 2690 if (!capable(CAP_SYS_ADMIN)) 2691 goto out; 2692 2693 ret = -EINPROGRESS; 2694 if (file->private_data) 2695 goto out; 2696 2697 ret = -EROFS; 2698 if (btrfs_root_readonly(root)) 2699 goto out; 2700 2701 ret = mnt_want_write_file(file); 2702 if (ret) 2703 goto out; 2704 2705 atomic_inc(&root->fs_info->open_ioctl_trans); 2706 2707 ret = -ENOMEM; 2708 trans = btrfs_start_ioctl_transaction(root); 2709 if (IS_ERR(trans)) 2710 goto out_drop; 2711 2712 file->private_data = trans; 2713 return 0; 2714 2715 out_drop: 2716 atomic_dec(&root->fs_info->open_ioctl_trans); 2717 mnt_drop_write_file(file); 2718 out: 2719 return ret; 2720 } 2721 2722 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) 2723 { 2724 struct inode *inode = fdentry(file)->d_inode; 2725 struct btrfs_root *root = BTRFS_I(inode)->root; 2726 struct btrfs_root *new_root; 2727 struct btrfs_dir_item *di; 2728 struct btrfs_trans_handle *trans; 2729 struct btrfs_path *path; 2730 struct btrfs_key location; 2731 struct btrfs_disk_key disk_key; 2732 struct btrfs_super_block *disk_super; 2733 u64 features; 2734 u64 objectid = 0; 2735 u64 dir_id; 2736 2737 if (!capable(CAP_SYS_ADMIN)) 2738 return -EPERM; 2739 2740 if (copy_from_user(&objectid, argp, sizeof(objectid))) 2741 return -EFAULT; 2742 2743 if (!objectid) 2744 objectid = root->root_key.objectid; 2745 2746 location.objectid = objectid; 2747 location.type = BTRFS_ROOT_ITEM_KEY; 2748 location.offset = (u64)-1; 2749 2750 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); 2751 if (IS_ERR(new_root)) 2752 return PTR_ERR(new_root); 2753 2754 if (btrfs_root_refs(&new_root->root_item) == 0) 2755 return -ENOENT; 2756 2757 path = btrfs_alloc_path(); 2758 if (!path) 2759 return -ENOMEM; 2760 path->leave_spinning = 1; 2761 2762 trans = btrfs_start_transaction(root, 1); 2763 if (IS_ERR(trans)) { 2764 btrfs_free_path(path); 2765 return PTR_ERR(trans); 2766 } 2767 2768 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 2769 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, 2770 dir_id, "default", 7, 1); 2771 if (IS_ERR_OR_NULL(di)) { 2772 btrfs_free_path(path); 2773 btrfs_end_transaction(trans, root); 2774 printk(KERN_ERR "Umm, you don't have the default dir item, " 2775 "this isn't going to work\n"); 2776 return -ENOENT; 2777 } 2778 2779 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); 2780 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); 2781 btrfs_mark_buffer_dirty(path->nodes[0]); 2782 btrfs_free_path(path); 2783 2784 disk_super = root->fs_info->super_copy; 2785 features = btrfs_super_incompat_flags(disk_super); 2786 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) { 2787 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL; 2788 btrfs_set_super_incompat_flags(disk_super, features); 2789 } 2790 btrfs_end_transaction(trans, root); 2791 2792 return 0; 2793 } 2794 2795 static void get_block_group_info(struct list_head *groups_list, 2796 struct btrfs_ioctl_space_info *space) 2797 { 2798 struct btrfs_block_group_cache *block_group; 2799 2800 space->total_bytes = 0; 2801 space->used_bytes = 0; 2802 space->flags = 0; 2803 list_for_each_entry(block_group, groups_list, list) { 2804 space->flags = block_group->flags; 2805 space->total_bytes += block_group->key.offset; 2806 space->used_bytes += 2807 btrfs_block_group_used(&block_group->item); 2808 } 2809 } 2810 2811 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) 2812 { 2813 struct btrfs_ioctl_space_args space_args; 2814 struct btrfs_ioctl_space_info space; 2815 struct btrfs_ioctl_space_info *dest; 2816 struct btrfs_ioctl_space_info *dest_orig; 2817 struct btrfs_ioctl_space_info __user *user_dest; 2818 struct btrfs_space_info *info; 2819 u64 types[] = {BTRFS_BLOCK_GROUP_DATA, 2820 BTRFS_BLOCK_GROUP_SYSTEM, 2821 BTRFS_BLOCK_GROUP_METADATA, 2822 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; 2823 int num_types = 4; 2824 int alloc_size; 2825 int ret = 0; 2826 u64 slot_count = 0; 2827 int i, c; 2828 2829 if (copy_from_user(&space_args, 2830 (struct btrfs_ioctl_space_args __user *)arg, 2831 sizeof(space_args))) 2832 return -EFAULT; 2833 2834 for (i = 0; i < num_types; i++) { 2835 struct btrfs_space_info *tmp; 2836 2837 info = NULL; 2838 rcu_read_lock(); 2839 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 2840 list) { 2841 if (tmp->flags == types[i]) { 2842 info = tmp; 2843 break; 2844 } 2845 } 2846 rcu_read_unlock(); 2847 2848 if (!info) 2849 continue; 2850 2851 down_read(&info->groups_sem); 2852 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 2853 if (!list_empty(&info->block_groups[c])) 2854 slot_count++; 2855 } 2856 up_read(&info->groups_sem); 2857 } 2858 2859 /* space_slots == 0 means they are asking for a count */ 2860 if (space_args.space_slots == 0) { 2861 space_args.total_spaces = slot_count; 2862 goto out; 2863 } 2864 2865 slot_count = min_t(u64, space_args.space_slots, slot_count); 2866 2867 alloc_size = sizeof(*dest) * slot_count; 2868 2869 /* we generally have at most 6 or so space infos, one for each raid 2870 * level. So, a whole page should be more than enough for everyone 2871 */ 2872 if (alloc_size > PAGE_CACHE_SIZE) 2873 return -ENOMEM; 2874 2875 space_args.total_spaces = 0; 2876 dest = kmalloc(alloc_size, GFP_NOFS); 2877 if (!dest) 2878 return -ENOMEM; 2879 dest_orig = dest; 2880 2881 /* now we have a buffer to copy into */ 2882 for (i = 0; i < num_types; i++) { 2883 struct btrfs_space_info *tmp; 2884 2885 if (!slot_count) 2886 break; 2887 2888 info = NULL; 2889 rcu_read_lock(); 2890 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 2891 list) { 2892 if (tmp->flags == types[i]) { 2893 info = tmp; 2894 break; 2895 } 2896 } 2897 rcu_read_unlock(); 2898 2899 if (!info) 2900 continue; 2901 down_read(&info->groups_sem); 2902 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 2903 if (!list_empty(&info->block_groups[c])) { 2904 get_block_group_info(&info->block_groups[c], 2905 &space); 2906 memcpy(dest, &space, sizeof(space)); 2907 dest++; 2908 space_args.total_spaces++; 2909 slot_count--; 2910 } 2911 if (!slot_count) 2912 break; 2913 } 2914 up_read(&info->groups_sem); 2915 } 2916 2917 user_dest = (struct btrfs_ioctl_space_info *) 2918 (arg + sizeof(struct btrfs_ioctl_space_args)); 2919 2920 if (copy_to_user(user_dest, dest_orig, alloc_size)) 2921 ret = -EFAULT; 2922 2923 kfree(dest_orig); 2924 out: 2925 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) 2926 ret = -EFAULT; 2927 2928 return ret; 2929 } 2930 2931 /* 2932 * there are many ways the trans_start and trans_end ioctls can lead 2933 * to deadlocks. They should only be used by applications that 2934 * basically own the machine, and have a very in depth understanding 2935 * of all the possible deadlocks and enospc problems. 2936 */ 2937 long btrfs_ioctl_trans_end(struct file *file) 2938 { 2939 struct inode *inode = fdentry(file)->d_inode; 2940 struct btrfs_root *root = BTRFS_I(inode)->root; 2941 struct btrfs_trans_handle *trans; 2942 2943 trans = file->private_data; 2944 if (!trans) 2945 return -EINVAL; 2946 file->private_data = NULL; 2947 2948 btrfs_end_transaction(trans, root); 2949 2950 atomic_dec(&root->fs_info->open_ioctl_trans); 2951 2952 mnt_drop_write_file(file); 2953 return 0; 2954 } 2955 2956 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp) 2957 { 2958 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 2959 struct btrfs_trans_handle *trans; 2960 u64 transid; 2961 int ret; 2962 2963 trans = btrfs_start_transaction(root, 0); 2964 if (IS_ERR(trans)) 2965 return PTR_ERR(trans); 2966 transid = trans->transid; 2967 ret = btrfs_commit_transaction_async(trans, root, 0); 2968 if (ret) { 2969 btrfs_end_transaction(trans, root); 2970 return ret; 2971 } 2972 2973 if (argp) 2974 if (copy_to_user(argp, &transid, sizeof(transid))) 2975 return -EFAULT; 2976 return 0; 2977 } 2978 2979 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp) 2980 { 2981 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 2982 u64 transid; 2983 2984 if (argp) { 2985 if (copy_from_user(&transid, argp, sizeof(transid))) 2986 return -EFAULT; 2987 } else { 2988 transid = 0; /* current trans */ 2989 } 2990 return btrfs_wait_for_commit(root, transid); 2991 } 2992 2993 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg) 2994 { 2995 int ret; 2996 struct btrfs_ioctl_scrub_args *sa; 2997 2998 if (!capable(CAP_SYS_ADMIN)) 2999 return -EPERM; 3000 3001 sa = memdup_user(arg, sizeof(*sa)); 3002 if (IS_ERR(sa)) 3003 return PTR_ERR(sa); 3004 3005 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end, 3006 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY); 3007 3008 if (copy_to_user(arg, sa, sizeof(*sa))) 3009 ret = -EFAULT; 3010 3011 kfree(sa); 3012 return ret; 3013 } 3014 3015 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg) 3016 { 3017 if (!capable(CAP_SYS_ADMIN)) 3018 return -EPERM; 3019 3020 return btrfs_scrub_cancel(root); 3021 } 3022 3023 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, 3024 void __user *arg) 3025 { 3026 struct btrfs_ioctl_scrub_args *sa; 3027 int ret; 3028 3029 if (!capable(CAP_SYS_ADMIN)) 3030 return -EPERM; 3031 3032 sa = memdup_user(arg, sizeof(*sa)); 3033 if (IS_ERR(sa)) 3034 return PTR_ERR(sa); 3035 3036 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress); 3037 3038 if (copy_to_user(arg, sa, sizeof(*sa))) 3039 ret = -EFAULT; 3040 3041 kfree(sa); 3042 return ret; 3043 } 3044 3045 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) 3046 { 3047 int ret = 0; 3048 int i; 3049 u64 rel_ptr; 3050 int size; 3051 struct btrfs_ioctl_ino_path_args *ipa = NULL; 3052 struct inode_fs_paths *ipath = NULL; 3053 struct btrfs_path *path; 3054 3055 if (!capable(CAP_SYS_ADMIN)) 3056 return -EPERM; 3057 3058 path = btrfs_alloc_path(); 3059 if (!path) { 3060 ret = -ENOMEM; 3061 goto out; 3062 } 3063 3064 ipa = memdup_user(arg, sizeof(*ipa)); 3065 if (IS_ERR(ipa)) { 3066 ret = PTR_ERR(ipa); 3067 ipa = NULL; 3068 goto out; 3069 } 3070 3071 size = min_t(u32, ipa->size, 4096); 3072 ipath = init_ipath(size, root, path); 3073 if (IS_ERR(ipath)) { 3074 ret = PTR_ERR(ipath); 3075 ipath = NULL; 3076 goto out; 3077 } 3078 3079 ret = paths_from_inode(ipa->inum, ipath); 3080 if (ret < 0) 3081 goto out; 3082 3083 for (i = 0; i < ipath->fspath->elem_cnt; ++i) { 3084 rel_ptr = ipath->fspath->val[i] - 3085 (u64)(unsigned long)ipath->fspath->val; 3086 ipath->fspath->val[i] = rel_ptr; 3087 } 3088 3089 ret = copy_to_user((void *)(unsigned long)ipa->fspath, 3090 (void *)(unsigned long)ipath->fspath, size); 3091 if (ret) { 3092 ret = -EFAULT; 3093 goto out; 3094 } 3095 3096 out: 3097 btrfs_free_path(path); 3098 free_ipath(ipath); 3099 kfree(ipa); 3100 3101 return ret; 3102 } 3103 3104 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) 3105 { 3106 struct btrfs_data_container *inodes = ctx; 3107 const size_t c = 3 * sizeof(u64); 3108 3109 if (inodes->bytes_left >= c) { 3110 inodes->bytes_left -= c; 3111 inodes->val[inodes->elem_cnt] = inum; 3112 inodes->val[inodes->elem_cnt + 1] = offset; 3113 inodes->val[inodes->elem_cnt + 2] = root; 3114 inodes->elem_cnt += 3; 3115 } else { 3116 inodes->bytes_missing += c - inodes->bytes_left; 3117 inodes->bytes_left = 0; 3118 inodes->elem_missed += 3; 3119 } 3120 3121 return 0; 3122 } 3123 3124 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 3125 void __user *arg) 3126 { 3127 int ret = 0; 3128 int size; 3129 u64 extent_item_pos; 3130 struct btrfs_ioctl_logical_ino_args *loi; 3131 struct btrfs_data_container *inodes = NULL; 3132 struct btrfs_path *path = NULL; 3133 struct btrfs_key key; 3134 3135 if (!capable(CAP_SYS_ADMIN)) 3136 return -EPERM; 3137 3138 loi = memdup_user(arg, sizeof(*loi)); 3139 if (IS_ERR(loi)) { 3140 ret = PTR_ERR(loi); 3141 loi = NULL; 3142 goto out; 3143 } 3144 3145 path = btrfs_alloc_path(); 3146 if (!path) { 3147 ret = -ENOMEM; 3148 goto out; 3149 } 3150 3151 size = min_t(u32, loi->size, 4096); 3152 inodes = init_data_container(size); 3153 if (IS_ERR(inodes)) { 3154 ret = PTR_ERR(inodes); 3155 inodes = NULL; 3156 goto out; 3157 } 3158 3159 ret = extent_from_logical(root->fs_info, loi->logical, path, &key); 3160 btrfs_release_path(path); 3161 3162 if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) 3163 ret = -ENOENT; 3164 if (ret < 0) 3165 goto out; 3166 3167 extent_item_pos = loi->logical - key.objectid; 3168 ret = iterate_extent_inodes(root->fs_info, key.objectid, 3169 extent_item_pos, 0, build_ino_list, 3170 inodes); 3171 3172 if (ret < 0) 3173 goto out; 3174 3175 ret = copy_to_user((void *)(unsigned long)loi->inodes, 3176 (void *)(unsigned long)inodes, size); 3177 if (ret) 3178 ret = -EFAULT; 3179 3180 out: 3181 btrfs_free_path(path); 3182 kfree(inodes); 3183 kfree(loi); 3184 3185 return ret; 3186 } 3187 3188 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3189 struct btrfs_ioctl_balance_args *bargs) 3190 { 3191 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3192 3193 bargs->flags = bctl->flags; 3194 3195 if (atomic_read(&fs_info->balance_running)) 3196 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 3197 if (atomic_read(&fs_info->balance_pause_req)) 3198 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 3199 if (atomic_read(&fs_info->balance_cancel_req)) 3200 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 3201 3202 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 3203 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 3204 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 3205 3206 if (lock) { 3207 spin_lock(&fs_info->balance_lock); 3208 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3209 spin_unlock(&fs_info->balance_lock); 3210 } else { 3211 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3212 } 3213 } 3214 3215 static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg) 3216 { 3217 struct btrfs_fs_info *fs_info = root->fs_info; 3218 struct btrfs_ioctl_balance_args *bargs; 3219 struct btrfs_balance_control *bctl; 3220 int ret; 3221 3222 if (!capable(CAP_SYS_ADMIN)) 3223 return -EPERM; 3224 3225 if (fs_info->sb->s_flags & MS_RDONLY) 3226 return -EROFS; 3227 3228 mutex_lock(&fs_info->volume_mutex); 3229 mutex_lock(&fs_info->balance_mutex); 3230 3231 if (arg) { 3232 bargs = memdup_user(arg, sizeof(*bargs)); 3233 if (IS_ERR(bargs)) { 3234 ret = PTR_ERR(bargs); 3235 goto out; 3236 } 3237 3238 if (bargs->flags & BTRFS_BALANCE_RESUME) { 3239 if (!fs_info->balance_ctl) { 3240 ret = -ENOTCONN; 3241 goto out_bargs; 3242 } 3243 3244 bctl = fs_info->balance_ctl; 3245 spin_lock(&fs_info->balance_lock); 3246 bctl->flags |= BTRFS_BALANCE_RESUME; 3247 spin_unlock(&fs_info->balance_lock); 3248 3249 goto do_balance; 3250 } 3251 } else { 3252 bargs = NULL; 3253 } 3254 3255 if (fs_info->balance_ctl) { 3256 ret = -EINPROGRESS; 3257 goto out_bargs; 3258 } 3259 3260 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3261 if (!bctl) { 3262 ret = -ENOMEM; 3263 goto out_bargs; 3264 } 3265 3266 bctl->fs_info = fs_info; 3267 if (arg) { 3268 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 3269 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 3270 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 3271 3272 bctl->flags = bargs->flags; 3273 } else { 3274 /* balance everything - no filters */ 3275 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 3276 } 3277 3278 do_balance: 3279 ret = btrfs_balance(bctl, bargs); 3280 /* 3281 * bctl is freed in __cancel_balance or in free_fs_info if 3282 * restriper was paused all the way until unmount 3283 */ 3284 if (arg) { 3285 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3286 ret = -EFAULT; 3287 } 3288 3289 out_bargs: 3290 kfree(bargs); 3291 out: 3292 mutex_unlock(&fs_info->balance_mutex); 3293 mutex_unlock(&fs_info->volume_mutex); 3294 return ret; 3295 } 3296 3297 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) 3298 { 3299 if (!capable(CAP_SYS_ADMIN)) 3300 return -EPERM; 3301 3302 switch (cmd) { 3303 case BTRFS_BALANCE_CTL_PAUSE: 3304 return btrfs_pause_balance(root->fs_info); 3305 case BTRFS_BALANCE_CTL_CANCEL: 3306 return btrfs_cancel_balance(root->fs_info); 3307 } 3308 3309 return -EINVAL; 3310 } 3311 3312 static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 3313 void __user *arg) 3314 { 3315 struct btrfs_fs_info *fs_info = root->fs_info; 3316 struct btrfs_ioctl_balance_args *bargs; 3317 int ret = 0; 3318 3319 if (!capable(CAP_SYS_ADMIN)) 3320 return -EPERM; 3321 3322 mutex_lock(&fs_info->balance_mutex); 3323 if (!fs_info->balance_ctl) { 3324 ret = -ENOTCONN; 3325 goto out; 3326 } 3327 3328 bargs = kzalloc(sizeof(*bargs), GFP_NOFS); 3329 if (!bargs) { 3330 ret = -ENOMEM; 3331 goto out; 3332 } 3333 3334 update_ioctl_balance_args(fs_info, 1, bargs); 3335 3336 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3337 ret = -EFAULT; 3338 3339 kfree(bargs); 3340 out: 3341 mutex_unlock(&fs_info->balance_mutex); 3342 return ret; 3343 } 3344 3345 long btrfs_ioctl(struct file *file, unsigned int 3346 cmd, unsigned long arg) 3347 { 3348 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 3349 void __user *argp = (void __user *)arg; 3350 3351 switch (cmd) { 3352 case FS_IOC_GETFLAGS: 3353 return btrfs_ioctl_getflags(file, argp); 3354 case FS_IOC_SETFLAGS: 3355 return btrfs_ioctl_setflags(file, argp); 3356 case FS_IOC_GETVERSION: 3357 return btrfs_ioctl_getversion(file, argp); 3358 case FITRIM: 3359 return btrfs_ioctl_fitrim(file, argp); 3360 case BTRFS_IOC_SNAP_CREATE: 3361 return btrfs_ioctl_snap_create(file, argp, 0); 3362 case BTRFS_IOC_SNAP_CREATE_V2: 3363 return btrfs_ioctl_snap_create_v2(file, argp, 0); 3364 case BTRFS_IOC_SUBVOL_CREATE: 3365 return btrfs_ioctl_snap_create(file, argp, 1); 3366 case BTRFS_IOC_SNAP_DESTROY: 3367 return btrfs_ioctl_snap_destroy(file, argp); 3368 case BTRFS_IOC_SUBVOL_GETFLAGS: 3369 return btrfs_ioctl_subvol_getflags(file, argp); 3370 case BTRFS_IOC_SUBVOL_SETFLAGS: 3371 return btrfs_ioctl_subvol_setflags(file, argp); 3372 case BTRFS_IOC_DEFAULT_SUBVOL: 3373 return btrfs_ioctl_default_subvol(file, argp); 3374 case BTRFS_IOC_DEFRAG: 3375 return btrfs_ioctl_defrag(file, NULL); 3376 case BTRFS_IOC_DEFRAG_RANGE: 3377 return btrfs_ioctl_defrag(file, argp); 3378 case BTRFS_IOC_RESIZE: 3379 return btrfs_ioctl_resize(root, argp); 3380 case BTRFS_IOC_ADD_DEV: 3381 return btrfs_ioctl_add_dev(root, argp); 3382 case BTRFS_IOC_RM_DEV: 3383 return btrfs_ioctl_rm_dev(root, argp); 3384 case BTRFS_IOC_FS_INFO: 3385 return btrfs_ioctl_fs_info(root, argp); 3386 case BTRFS_IOC_DEV_INFO: 3387 return btrfs_ioctl_dev_info(root, argp); 3388 case BTRFS_IOC_BALANCE: 3389 return btrfs_ioctl_balance(root, NULL); 3390 case BTRFS_IOC_CLONE: 3391 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 3392 case BTRFS_IOC_CLONE_RANGE: 3393 return btrfs_ioctl_clone_range(file, argp); 3394 case BTRFS_IOC_TRANS_START: 3395 return btrfs_ioctl_trans_start(file); 3396 case BTRFS_IOC_TRANS_END: 3397 return btrfs_ioctl_trans_end(file); 3398 case BTRFS_IOC_TREE_SEARCH: 3399 return btrfs_ioctl_tree_search(file, argp); 3400 case BTRFS_IOC_INO_LOOKUP: 3401 return btrfs_ioctl_ino_lookup(file, argp); 3402 case BTRFS_IOC_INO_PATHS: 3403 return btrfs_ioctl_ino_to_path(root, argp); 3404 case BTRFS_IOC_LOGICAL_INO: 3405 return btrfs_ioctl_logical_to_ino(root, argp); 3406 case BTRFS_IOC_SPACE_INFO: 3407 return btrfs_ioctl_space_info(root, argp); 3408 case BTRFS_IOC_SYNC: 3409 btrfs_sync_fs(file->f_dentry->d_sb, 1); 3410 return 0; 3411 case BTRFS_IOC_START_SYNC: 3412 return btrfs_ioctl_start_sync(file, argp); 3413 case BTRFS_IOC_WAIT_SYNC: 3414 return btrfs_ioctl_wait_sync(file, argp); 3415 case BTRFS_IOC_SCRUB: 3416 return btrfs_ioctl_scrub(root, argp); 3417 case BTRFS_IOC_SCRUB_CANCEL: 3418 return btrfs_ioctl_scrub_cancel(root, argp); 3419 case BTRFS_IOC_SCRUB_PROGRESS: 3420 return btrfs_ioctl_scrub_progress(root, argp); 3421 case BTRFS_IOC_BALANCE_V2: 3422 return btrfs_ioctl_balance(root, argp); 3423 case BTRFS_IOC_BALANCE_CTL: 3424 return btrfs_ioctl_balance_ctl(root, arg); 3425 case BTRFS_IOC_BALANCE_PROGRESS: 3426 return btrfs_ioctl_balance_progress(root, argp); 3427 } 3428 3429 return -ENOTTY; 3430 } 3431