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