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 <linux/uuid.h> 45 #include <linux/btrfs.h> 46 #include "compat.h" 47 #include "ctree.h" 48 #include "disk-io.h" 49 #include "transaction.h" 50 #include "btrfs_inode.h" 51 #include "print-tree.h" 52 #include "volumes.h" 53 #include "locking.h" 54 #include "inode-map.h" 55 #include "backref.h" 56 #include "rcu-string.h" 57 #include "send.h" 58 #include "dev-replace.h" 59 60 /* Mask out flags that are inappropriate for the given type of inode. */ 61 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags) 62 { 63 if (S_ISDIR(mode)) 64 return flags; 65 else if (S_ISREG(mode)) 66 return flags & ~FS_DIRSYNC_FL; 67 else 68 return flags & (FS_NODUMP_FL | FS_NOATIME_FL); 69 } 70 71 /* 72 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl. 73 */ 74 static unsigned int btrfs_flags_to_ioctl(unsigned int flags) 75 { 76 unsigned int iflags = 0; 77 78 if (flags & BTRFS_INODE_SYNC) 79 iflags |= FS_SYNC_FL; 80 if (flags & BTRFS_INODE_IMMUTABLE) 81 iflags |= FS_IMMUTABLE_FL; 82 if (flags & BTRFS_INODE_APPEND) 83 iflags |= FS_APPEND_FL; 84 if (flags & BTRFS_INODE_NODUMP) 85 iflags |= FS_NODUMP_FL; 86 if (flags & BTRFS_INODE_NOATIME) 87 iflags |= FS_NOATIME_FL; 88 if (flags & BTRFS_INODE_DIRSYNC) 89 iflags |= FS_DIRSYNC_FL; 90 if (flags & BTRFS_INODE_NODATACOW) 91 iflags |= FS_NOCOW_FL; 92 93 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS)) 94 iflags |= FS_COMPR_FL; 95 else if (flags & BTRFS_INODE_NOCOMPRESS) 96 iflags |= FS_NOCOMP_FL; 97 98 return iflags; 99 } 100 101 /* 102 * Update inode->i_flags based on the btrfs internal flags. 103 */ 104 void btrfs_update_iflags(struct inode *inode) 105 { 106 struct btrfs_inode *ip = BTRFS_I(inode); 107 108 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); 109 110 if (ip->flags & BTRFS_INODE_SYNC) 111 inode->i_flags |= S_SYNC; 112 if (ip->flags & BTRFS_INODE_IMMUTABLE) 113 inode->i_flags |= S_IMMUTABLE; 114 if (ip->flags & BTRFS_INODE_APPEND) 115 inode->i_flags |= S_APPEND; 116 if (ip->flags & BTRFS_INODE_NOATIME) 117 inode->i_flags |= S_NOATIME; 118 if (ip->flags & BTRFS_INODE_DIRSYNC) 119 inode->i_flags |= S_DIRSYNC; 120 } 121 122 /* 123 * Inherit flags from the parent inode. 124 * 125 * Currently only the compression flags and the cow flags are inherited. 126 */ 127 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) 128 { 129 unsigned int flags; 130 131 if (!dir) 132 return; 133 134 flags = BTRFS_I(dir)->flags; 135 136 if (flags & BTRFS_INODE_NOCOMPRESS) { 137 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS; 138 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; 139 } else if (flags & BTRFS_INODE_COMPRESS) { 140 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS; 141 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS; 142 } 143 144 if (flags & BTRFS_INODE_NODATACOW) { 145 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; 146 if (S_ISREG(inode->i_mode)) 147 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; 148 } 149 150 btrfs_update_iflags(inode); 151 } 152 153 static int btrfs_ioctl_getflags(struct file *file, void __user *arg) 154 { 155 struct btrfs_inode *ip = BTRFS_I(file_inode(file)); 156 unsigned int flags = btrfs_flags_to_ioctl(ip->flags); 157 158 if (copy_to_user(arg, &flags, sizeof(flags))) 159 return -EFAULT; 160 return 0; 161 } 162 163 static int check_flags(unsigned int flags) 164 { 165 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ 166 FS_NOATIME_FL | FS_NODUMP_FL | \ 167 FS_SYNC_FL | FS_DIRSYNC_FL | \ 168 FS_NOCOMP_FL | FS_COMPR_FL | 169 FS_NOCOW_FL)) 170 return -EOPNOTSUPP; 171 172 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) 173 return -EINVAL; 174 175 return 0; 176 } 177 178 static int btrfs_ioctl_setflags(struct file *file, void __user *arg) 179 { 180 struct inode *inode = file_inode(file); 181 struct btrfs_inode *ip = BTRFS_I(inode); 182 struct btrfs_root *root = ip->root; 183 struct btrfs_trans_handle *trans; 184 unsigned int flags, oldflags; 185 int ret; 186 u64 ip_oldflags; 187 unsigned int i_oldflags; 188 umode_t mode; 189 190 if (btrfs_root_readonly(root)) 191 return -EROFS; 192 193 if (copy_from_user(&flags, arg, sizeof(flags))) 194 return -EFAULT; 195 196 ret = check_flags(flags); 197 if (ret) 198 return ret; 199 200 if (!inode_owner_or_capable(inode)) 201 return -EACCES; 202 203 ret = mnt_want_write_file(file); 204 if (ret) 205 return ret; 206 207 mutex_lock(&inode->i_mutex); 208 209 ip_oldflags = ip->flags; 210 i_oldflags = inode->i_flags; 211 mode = inode->i_mode; 212 213 flags = btrfs_mask_flags(inode->i_mode, flags); 214 oldflags = btrfs_flags_to_ioctl(ip->flags); 215 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { 216 if (!capable(CAP_LINUX_IMMUTABLE)) { 217 ret = -EPERM; 218 goto out_unlock; 219 } 220 } 221 222 if (flags & FS_SYNC_FL) 223 ip->flags |= BTRFS_INODE_SYNC; 224 else 225 ip->flags &= ~BTRFS_INODE_SYNC; 226 if (flags & FS_IMMUTABLE_FL) 227 ip->flags |= BTRFS_INODE_IMMUTABLE; 228 else 229 ip->flags &= ~BTRFS_INODE_IMMUTABLE; 230 if (flags & FS_APPEND_FL) 231 ip->flags |= BTRFS_INODE_APPEND; 232 else 233 ip->flags &= ~BTRFS_INODE_APPEND; 234 if (flags & FS_NODUMP_FL) 235 ip->flags |= BTRFS_INODE_NODUMP; 236 else 237 ip->flags &= ~BTRFS_INODE_NODUMP; 238 if (flags & FS_NOATIME_FL) 239 ip->flags |= BTRFS_INODE_NOATIME; 240 else 241 ip->flags &= ~BTRFS_INODE_NOATIME; 242 if (flags & FS_DIRSYNC_FL) 243 ip->flags |= BTRFS_INODE_DIRSYNC; 244 else 245 ip->flags &= ~BTRFS_INODE_DIRSYNC; 246 if (flags & FS_NOCOW_FL) { 247 if (S_ISREG(mode)) { 248 /* 249 * It's safe to turn csums off here, no extents exist. 250 * Otherwise we want the flag to reflect the real COW 251 * status of the file and will not set it. 252 */ 253 if (inode->i_size == 0) 254 ip->flags |= BTRFS_INODE_NODATACOW 255 | BTRFS_INODE_NODATASUM; 256 } else { 257 ip->flags |= BTRFS_INODE_NODATACOW; 258 } 259 } else { 260 /* 261 * Revert back under same assuptions as above 262 */ 263 if (S_ISREG(mode)) { 264 if (inode->i_size == 0) 265 ip->flags &= ~(BTRFS_INODE_NODATACOW 266 | BTRFS_INODE_NODATASUM); 267 } else { 268 ip->flags &= ~BTRFS_INODE_NODATACOW; 269 } 270 } 271 272 /* 273 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS 274 * flag may be changed automatically if compression code won't make 275 * things smaller. 276 */ 277 if (flags & FS_NOCOMP_FL) { 278 ip->flags &= ~BTRFS_INODE_COMPRESS; 279 ip->flags |= BTRFS_INODE_NOCOMPRESS; 280 } else if (flags & FS_COMPR_FL) { 281 ip->flags |= BTRFS_INODE_COMPRESS; 282 ip->flags &= ~BTRFS_INODE_NOCOMPRESS; 283 } else { 284 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); 285 } 286 287 trans = btrfs_start_transaction(root, 1); 288 if (IS_ERR(trans)) { 289 ret = PTR_ERR(trans); 290 goto out_drop; 291 } 292 293 btrfs_update_iflags(inode); 294 inode_inc_iversion(inode); 295 inode->i_ctime = CURRENT_TIME; 296 ret = btrfs_update_inode(trans, root, inode); 297 298 btrfs_end_transaction(trans, root); 299 out_drop: 300 if (ret) { 301 ip->flags = ip_oldflags; 302 inode->i_flags = i_oldflags; 303 } 304 305 out_unlock: 306 mutex_unlock(&inode->i_mutex); 307 mnt_drop_write_file(file); 308 return ret; 309 } 310 311 static int btrfs_ioctl_getversion(struct file *file, int __user *arg) 312 { 313 struct inode *inode = file_inode(file); 314 315 return put_user(inode->i_generation, arg); 316 } 317 318 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) 319 { 320 struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb); 321 struct btrfs_device *device; 322 struct request_queue *q; 323 struct fstrim_range range; 324 u64 minlen = ULLONG_MAX; 325 u64 num_devices = 0; 326 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy); 327 int ret; 328 329 if (!capable(CAP_SYS_ADMIN)) 330 return -EPERM; 331 332 rcu_read_lock(); 333 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices, 334 dev_list) { 335 if (!device->bdev) 336 continue; 337 q = bdev_get_queue(device->bdev); 338 if (blk_queue_discard(q)) { 339 num_devices++; 340 minlen = min((u64)q->limits.discard_granularity, 341 minlen); 342 } 343 } 344 rcu_read_unlock(); 345 346 if (!num_devices) 347 return -EOPNOTSUPP; 348 if (copy_from_user(&range, arg, sizeof(range))) 349 return -EFAULT; 350 if (range.start > total_bytes || 351 range.len < fs_info->sb->s_blocksize) 352 return -EINVAL; 353 354 range.len = min(range.len, total_bytes - range.start); 355 range.minlen = max(range.minlen, minlen); 356 ret = btrfs_trim_fs(fs_info->tree_root, &range); 357 if (ret < 0) 358 return ret; 359 360 if (copy_to_user(arg, &range, sizeof(range))) 361 return -EFAULT; 362 363 return 0; 364 } 365 366 static noinline int create_subvol(struct inode *dir, 367 struct dentry *dentry, 368 char *name, int namelen, 369 u64 *async_transid, 370 struct btrfs_qgroup_inherit *inherit) 371 { 372 struct btrfs_trans_handle *trans; 373 struct btrfs_key key; 374 struct btrfs_root_item root_item; 375 struct btrfs_inode_item *inode_item; 376 struct extent_buffer *leaf; 377 struct btrfs_root *root = BTRFS_I(dir)->root; 378 struct btrfs_root *new_root; 379 struct btrfs_block_rsv block_rsv; 380 struct timespec cur_time = CURRENT_TIME; 381 int ret; 382 int err; 383 u64 objectid; 384 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; 385 u64 index = 0; 386 u64 qgroup_reserved; 387 uuid_le new_uuid; 388 389 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid); 390 if (ret) 391 return ret; 392 393 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); 394 /* 395 * The same as the snapshot creation, please see the comment 396 * of create_snapshot(). 397 */ 398 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 399 7, &qgroup_reserved); 400 if (ret) 401 return ret; 402 403 trans = btrfs_start_transaction(root, 0); 404 if (IS_ERR(trans)) { 405 ret = PTR_ERR(trans); 406 goto out; 407 } 408 trans->block_rsv = &block_rsv; 409 trans->bytes_reserved = block_rsv.size; 410 411 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit); 412 if (ret) 413 goto fail; 414 415 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 416 0, objectid, NULL, 0, 0, 0); 417 if (IS_ERR(leaf)) { 418 ret = PTR_ERR(leaf); 419 goto fail; 420 } 421 422 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header)); 423 btrfs_set_header_bytenr(leaf, leaf->start); 424 btrfs_set_header_generation(leaf, trans->transid); 425 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV); 426 btrfs_set_header_owner(leaf, objectid); 427 428 write_extent_buffer(leaf, root->fs_info->fsid, 429 (unsigned long)btrfs_header_fsid(leaf), 430 BTRFS_FSID_SIZE); 431 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 432 (unsigned long)btrfs_header_chunk_tree_uuid(leaf), 433 BTRFS_UUID_SIZE); 434 btrfs_mark_buffer_dirty(leaf); 435 436 memset(&root_item, 0, sizeof(root_item)); 437 438 inode_item = &root_item.inode; 439 inode_item->generation = cpu_to_le64(1); 440 inode_item->size = cpu_to_le64(3); 441 inode_item->nlink = cpu_to_le32(1); 442 inode_item->nbytes = cpu_to_le64(root->leafsize); 443 inode_item->mode = cpu_to_le32(S_IFDIR | 0755); 444 445 root_item.flags = 0; 446 root_item.byte_limit = 0; 447 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT); 448 449 btrfs_set_root_bytenr(&root_item, leaf->start); 450 btrfs_set_root_generation(&root_item, trans->transid); 451 btrfs_set_root_level(&root_item, 0); 452 btrfs_set_root_refs(&root_item, 1); 453 btrfs_set_root_used(&root_item, leaf->len); 454 btrfs_set_root_last_snapshot(&root_item, 0); 455 456 btrfs_set_root_generation_v2(&root_item, 457 btrfs_root_generation(&root_item)); 458 uuid_le_gen(&new_uuid); 459 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE); 460 root_item.otime.sec = cpu_to_le64(cur_time.tv_sec); 461 root_item.otime.nsec = cpu_to_le32(cur_time.tv_nsec); 462 root_item.ctime = root_item.otime; 463 btrfs_set_root_ctransid(&root_item, trans->transid); 464 btrfs_set_root_otransid(&root_item, trans->transid); 465 466 btrfs_tree_unlock(leaf); 467 free_extent_buffer(leaf); 468 leaf = NULL; 469 470 btrfs_set_root_dirid(&root_item, new_dirid); 471 472 key.objectid = objectid; 473 key.offset = 0; 474 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); 475 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, 476 &root_item); 477 if (ret) 478 goto fail; 479 480 key.offset = (u64)-1; 481 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); 482 if (IS_ERR(new_root)) { 483 btrfs_abort_transaction(trans, root, PTR_ERR(new_root)); 484 ret = PTR_ERR(new_root); 485 goto fail; 486 } 487 488 btrfs_record_root_in_trans(trans, new_root); 489 490 ret = btrfs_create_subvol_root(trans, new_root, new_dirid); 491 if (ret) { 492 /* We potentially lose an unused inode item here */ 493 btrfs_abort_transaction(trans, root, ret); 494 goto fail; 495 } 496 497 /* 498 * insert the directory item 499 */ 500 ret = btrfs_set_inode_index(dir, &index); 501 if (ret) { 502 btrfs_abort_transaction(trans, root, ret); 503 goto fail; 504 } 505 506 ret = btrfs_insert_dir_item(trans, root, 507 name, namelen, dir, &key, 508 BTRFS_FT_DIR, index); 509 if (ret) { 510 btrfs_abort_transaction(trans, root, ret); 511 goto fail; 512 } 513 514 btrfs_i_size_write(dir, dir->i_size + namelen * 2); 515 ret = btrfs_update_inode(trans, root, dir); 516 BUG_ON(ret); 517 518 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, 519 objectid, root->root_key.objectid, 520 btrfs_ino(dir), index, name, namelen); 521 522 BUG_ON(ret); 523 524 fail: 525 trans->block_rsv = NULL; 526 trans->bytes_reserved = 0; 527 if (async_transid) { 528 *async_transid = trans->transid; 529 err = btrfs_commit_transaction_async(trans, root, 1); 530 } else { 531 err = btrfs_commit_transaction(trans, root); 532 } 533 if (err && !ret) 534 ret = err; 535 536 if (!ret) 537 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry)); 538 out: 539 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); 540 return ret; 541 } 542 543 static int create_snapshot(struct btrfs_root *root, struct inode *dir, 544 struct dentry *dentry, char *name, int namelen, 545 u64 *async_transid, bool readonly, 546 struct btrfs_qgroup_inherit *inherit) 547 { 548 struct inode *inode; 549 struct btrfs_pending_snapshot *pending_snapshot; 550 struct btrfs_trans_handle *trans; 551 int ret; 552 553 if (!root->ref_cows) 554 return -EINVAL; 555 556 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); 557 if (!pending_snapshot) 558 return -ENOMEM; 559 560 btrfs_init_block_rsv(&pending_snapshot->block_rsv, 561 BTRFS_BLOCK_RSV_TEMP); 562 /* 563 * 1 - parent dir inode 564 * 2 - dir entries 565 * 1 - root item 566 * 2 - root ref/backref 567 * 1 - root of snapshot 568 */ 569 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, 570 &pending_snapshot->block_rsv, 7, 571 &pending_snapshot->qgroup_reserved); 572 if (ret) 573 goto out; 574 575 pending_snapshot->dentry = dentry; 576 pending_snapshot->root = root; 577 pending_snapshot->readonly = readonly; 578 pending_snapshot->dir = dir; 579 pending_snapshot->inherit = inherit; 580 581 trans = btrfs_start_transaction(root, 0); 582 if (IS_ERR(trans)) { 583 ret = PTR_ERR(trans); 584 goto fail; 585 } 586 587 spin_lock(&root->fs_info->trans_lock); 588 list_add(&pending_snapshot->list, 589 &trans->transaction->pending_snapshots); 590 spin_unlock(&root->fs_info->trans_lock); 591 if (async_transid) { 592 *async_transid = trans->transid; 593 ret = btrfs_commit_transaction_async(trans, 594 root->fs_info->extent_root, 1); 595 } else { 596 ret = btrfs_commit_transaction(trans, 597 root->fs_info->extent_root); 598 } 599 if (ret) { 600 /* cleanup_transaction has freed this for us */ 601 if (trans->aborted) 602 pending_snapshot = NULL; 603 goto fail; 604 } 605 606 ret = pending_snapshot->error; 607 if (ret) 608 goto fail; 609 610 ret = btrfs_orphan_cleanup(pending_snapshot->snap); 611 if (ret) 612 goto fail; 613 614 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry); 615 if (IS_ERR(inode)) { 616 ret = PTR_ERR(inode); 617 goto fail; 618 } 619 BUG_ON(!inode); 620 d_instantiate(dentry, inode); 621 ret = 0; 622 fail: 623 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root, 624 &pending_snapshot->block_rsv, 625 pending_snapshot->qgroup_reserved); 626 out: 627 kfree(pending_snapshot); 628 return ret; 629 } 630 631 /* copy of check_sticky in fs/namei.c() 632 * It's inline, so penalty for filesystems that don't use sticky bit is 633 * minimal. 634 */ 635 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode) 636 { 637 kuid_t fsuid = current_fsuid(); 638 639 if (!(dir->i_mode & S_ISVTX)) 640 return 0; 641 if (uid_eq(inode->i_uid, fsuid)) 642 return 0; 643 if (uid_eq(dir->i_uid, fsuid)) 644 return 0; 645 return !capable(CAP_FOWNER); 646 } 647 648 /* copy of may_delete in fs/namei.c() 649 * Check whether we can remove a link victim from directory dir, check 650 * whether the type of victim is right. 651 * 1. We can't do it if dir is read-only (done in permission()) 652 * 2. We should have write and exec permissions on dir 653 * 3. We can't remove anything from append-only dir 654 * 4. We can't do anything with immutable dir (done in permission()) 655 * 5. If the sticky bit on dir is set we should either 656 * a. be owner of dir, or 657 * b. be owner of victim, or 658 * c. have CAP_FOWNER capability 659 * 6. If the victim is append-only or immutable we can't do antyhing with 660 * links pointing to it. 661 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. 662 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. 663 * 9. We can't remove a root or mountpoint. 664 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by 665 * nfs_async_unlink(). 666 */ 667 668 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir) 669 { 670 int error; 671 672 if (!victim->d_inode) 673 return -ENOENT; 674 675 BUG_ON(victim->d_parent->d_inode != dir); 676 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); 677 678 error = inode_permission(dir, MAY_WRITE | MAY_EXEC); 679 if (error) 680 return error; 681 if (IS_APPEND(dir)) 682 return -EPERM; 683 if (btrfs_check_sticky(dir, victim->d_inode)|| 684 IS_APPEND(victim->d_inode)|| 685 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) 686 return -EPERM; 687 if (isdir) { 688 if (!S_ISDIR(victim->d_inode->i_mode)) 689 return -ENOTDIR; 690 if (IS_ROOT(victim)) 691 return -EBUSY; 692 } else if (S_ISDIR(victim->d_inode->i_mode)) 693 return -EISDIR; 694 if (IS_DEADDIR(dir)) 695 return -ENOENT; 696 if (victim->d_flags & DCACHE_NFSFS_RENAMED) 697 return -EBUSY; 698 return 0; 699 } 700 701 /* copy of may_create in fs/namei.c() */ 702 static inline int btrfs_may_create(struct inode *dir, struct dentry *child) 703 { 704 if (child->d_inode) 705 return -EEXIST; 706 if (IS_DEADDIR(dir)) 707 return -ENOENT; 708 return inode_permission(dir, MAY_WRITE | MAY_EXEC); 709 } 710 711 /* 712 * Create a new subvolume below @parent. This is largely modeled after 713 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup 714 * inside this filesystem so it's quite a bit simpler. 715 */ 716 static noinline int btrfs_mksubvol(struct path *parent, 717 char *name, int namelen, 718 struct btrfs_root *snap_src, 719 u64 *async_transid, bool readonly, 720 struct btrfs_qgroup_inherit *inherit) 721 { 722 struct inode *dir = parent->dentry->d_inode; 723 struct dentry *dentry; 724 int error; 725 726 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 727 728 dentry = lookup_one_len(name, parent->dentry, namelen); 729 error = PTR_ERR(dentry); 730 if (IS_ERR(dentry)) 731 goto out_unlock; 732 733 error = -EEXIST; 734 if (dentry->d_inode) 735 goto out_dput; 736 737 error = btrfs_may_create(dir, dentry); 738 if (error) 739 goto out_dput; 740 741 /* 742 * even if this name doesn't exist, we may get hash collisions. 743 * check for them now when we can safely fail 744 */ 745 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root, 746 dir->i_ino, name, 747 namelen); 748 if (error) 749 goto out_dput; 750 751 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 752 753 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) 754 goto out_up_read; 755 756 if (snap_src) { 757 error = create_snapshot(snap_src, dir, dentry, name, namelen, 758 async_transid, readonly, inherit); 759 } else { 760 error = create_subvol(dir, dentry, name, namelen, 761 async_transid, inherit); 762 } 763 if (!error) 764 fsnotify_mkdir(dir, dentry); 765 out_up_read: 766 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 767 out_dput: 768 dput(dentry); 769 out_unlock: 770 mutex_unlock(&dir->i_mutex); 771 return error; 772 } 773 774 /* 775 * When we're defragging a range, we don't want to kick it off again 776 * if it is really just waiting for delalloc to send it down. 777 * If we find a nice big extent or delalloc range for the bytes in the 778 * file you want to defrag, we return 0 to let you know to skip this 779 * part of the file 780 */ 781 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh) 782 { 783 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 784 struct extent_map *em = NULL; 785 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 786 u64 end; 787 788 read_lock(&em_tree->lock); 789 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); 790 read_unlock(&em_tree->lock); 791 792 if (em) { 793 end = extent_map_end(em); 794 free_extent_map(em); 795 if (end - offset > thresh) 796 return 0; 797 } 798 /* if we already have a nice delalloc here, just stop */ 799 thresh /= 2; 800 end = count_range_bits(io_tree, &offset, offset + thresh, 801 thresh, EXTENT_DELALLOC, 1); 802 if (end >= thresh) 803 return 0; 804 return 1; 805 } 806 807 /* 808 * helper function to walk through a file and find extents 809 * newer than a specific transid, and smaller than thresh. 810 * 811 * This is used by the defragging code to find new and small 812 * extents 813 */ 814 static int find_new_extents(struct btrfs_root *root, 815 struct inode *inode, u64 newer_than, 816 u64 *off, int thresh) 817 { 818 struct btrfs_path *path; 819 struct btrfs_key min_key; 820 struct btrfs_key max_key; 821 struct extent_buffer *leaf; 822 struct btrfs_file_extent_item *extent; 823 int type; 824 int ret; 825 u64 ino = btrfs_ino(inode); 826 827 path = btrfs_alloc_path(); 828 if (!path) 829 return -ENOMEM; 830 831 min_key.objectid = ino; 832 min_key.type = BTRFS_EXTENT_DATA_KEY; 833 min_key.offset = *off; 834 835 max_key.objectid = ino; 836 max_key.type = (u8)-1; 837 max_key.offset = (u64)-1; 838 839 path->keep_locks = 1; 840 841 while(1) { 842 ret = btrfs_search_forward(root, &min_key, &max_key, 843 path, newer_than); 844 if (ret != 0) 845 goto none; 846 if (min_key.objectid != ino) 847 goto none; 848 if (min_key.type != BTRFS_EXTENT_DATA_KEY) 849 goto none; 850 851 leaf = path->nodes[0]; 852 extent = btrfs_item_ptr(leaf, path->slots[0], 853 struct btrfs_file_extent_item); 854 855 type = btrfs_file_extent_type(leaf, extent); 856 if (type == BTRFS_FILE_EXTENT_REG && 857 btrfs_file_extent_num_bytes(leaf, extent) < thresh && 858 check_defrag_in_cache(inode, min_key.offset, thresh)) { 859 *off = min_key.offset; 860 btrfs_free_path(path); 861 return 0; 862 } 863 864 if (min_key.offset == (u64)-1) 865 goto none; 866 867 min_key.offset++; 868 btrfs_release_path(path); 869 } 870 none: 871 btrfs_free_path(path); 872 return -ENOENT; 873 } 874 875 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start) 876 { 877 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 878 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 879 struct extent_map *em; 880 u64 len = PAGE_CACHE_SIZE; 881 882 /* 883 * hopefully we have this extent in the tree already, try without 884 * the full extent lock 885 */ 886 read_lock(&em_tree->lock); 887 em = lookup_extent_mapping(em_tree, start, len); 888 read_unlock(&em_tree->lock); 889 890 if (!em) { 891 /* get the big lock and read metadata off disk */ 892 lock_extent(io_tree, start, start + len - 1); 893 em = btrfs_get_extent(inode, NULL, 0, start, len, 0); 894 unlock_extent(io_tree, start, start + len - 1); 895 896 if (IS_ERR(em)) 897 return NULL; 898 } 899 900 return em; 901 } 902 903 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) 904 { 905 struct extent_map *next; 906 bool ret = true; 907 908 /* this is the last extent */ 909 if (em->start + em->len >= i_size_read(inode)) 910 return false; 911 912 next = defrag_lookup_extent(inode, em->start + em->len); 913 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) 914 ret = false; 915 916 free_extent_map(next); 917 return ret; 918 } 919 920 static int should_defrag_range(struct inode *inode, u64 start, int thresh, 921 u64 *last_len, u64 *skip, u64 *defrag_end, 922 int compress) 923 { 924 struct extent_map *em; 925 int ret = 1; 926 bool next_mergeable = true; 927 928 /* 929 * make sure that once we start defragging an extent, we keep on 930 * defragging it 931 */ 932 if (start < *defrag_end) 933 return 1; 934 935 *skip = 0; 936 937 em = defrag_lookup_extent(inode, start); 938 if (!em) 939 return 0; 940 941 /* this will cover holes, and inline extents */ 942 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 943 ret = 0; 944 goto out; 945 } 946 947 next_mergeable = defrag_check_next_extent(inode, em); 948 949 /* 950 * we hit a real extent, if it is big or the next extent is not a 951 * real extent, don't bother defragging it 952 */ 953 if (!compress && (*last_len == 0 || *last_len >= thresh) && 954 (em->len >= thresh || !next_mergeable)) 955 ret = 0; 956 out: 957 /* 958 * last_len ends up being a counter of how many bytes we've defragged. 959 * every time we choose not to defrag an extent, we reset *last_len 960 * so that the next tiny extent will force a defrag. 961 * 962 * The end result of this is that tiny extents before a single big 963 * extent will force at least part of that big extent to be defragged. 964 */ 965 if (ret) { 966 *defrag_end = extent_map_end(em); 967 } else { 968 *last_len = 0; 969 *skip = extent_map_end(em); 970 *defrag_end = 0; 971 } 972 973 free_extent_map(em); 974 return ret; 975 } 976 977 /* 978 * it doesn't do much good to defrag one or two pages 979 * at a time. This pulls in a nice chunk of pages 980 * to COW and defrag. 981 * 982 * It also makes sure the delalloc code has enough 983 * dirty data to avoid making new small extents as part 984 * of the defrag 985 * 986 * It's a good idea to start RA on this range 987 * before calling this. 988 */ 989 static int cluster_pages_for_defrag(struct inode *inode, 990 struct page **pages, 991 unsigned long start_index, 992 int num_pages) 993 { 994 unsigned long file_end; 995 u64 isize = i_size_read(inode); 996 u64 page_start; 997 u64 page_end; 998 u64 page_cnt; 999 int ret; 1000 int i; 1001 int i_done; 1002 struct btrfs_ordered_extent *ordered; 1003 struct extent_state *cached_state = NULL; 1004 struct extent_io_tree *tree; 1005 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 1006 1007 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 1008 if (!isize || start_index > file_end) 1009 return 0; 1010 1011 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); 1012 1013 ret = btrfs_delalloc_reserve_space(inode, 1014 page_cnt << PAGE_CACHE_SHIFT); 1015 if (ret) 1016 return ret; 1017 i_done = 0; 1018 tree = &BTRFS_I(inode)->io_tree; 1019 1020 /* step one, lock all the pages */ 1021 for (i = 0; i < page_cnt; i++) { 1022 struct page *page; 1023 again: 1024 page = find_or_create_page(inode->i_mapping, 1025 start_index + i, mask); 1026 if (!page) 1027 break; 1028 1029 page_start = page_offset(page); 1030 page_end = page_start + PAGE_CACHE_SIZE - 1; 1031 while (1) { 1032 lock_extent(tree, page_start, page_end); 1033 ordered = btrfs_lookup_ordered_extent(inode, 1034 page_start); 1035 unlock_extent(tree, page_start, page_end); 1036 if (!ordered) 1037 break; 1038 1039 unlock_page(page); 1040 btrfs_start_ordered_extent(inode, ordered, 1); 1041 btrfs_put_ordered_extent(ordered); 1042 lock_page(page); 1043 /* 1044 * we unlocked the page above, so we need check if 1045 * it was released or not. 1046 */ 1047 if (page->mapping != inode->i_mapping) { 1048 unlock_page(page); 1049 page_cache_release(page); 1050 goto again; 1051 } 1052 } 1053 1054 if (!PageUptodate(page)) { 1055 btrfs_readpage(NULL, page); 1056 lock_page(page); 1057 if (!PageUptodate(page)) { 1058 unlock_page(page); 1059 page_cache_release(page); 1060 ret = -EIO; 1061 break; 1062 } 1063 } 1064 1065 if (page->mapping != inode->i_mapping) { 1066 unlock_page(page); 1067 page_cache_release(page); 1068 goto again; 1069 } 1070 1071 pages[i] = page; 1072 i_done++; 1073 } 1074 if (!i_done || ret) 1075 goto out; 1076 1077 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1078 goto out; 1079 1080 /* 1081 * so now we have a nice long stream of locked 1082 * and up to date pages, lets wait on them 1083 */ 1084 for (i = 0; i < i_done; i++) 1085 wait_on_page_writeback(pages[i]); 1086 1087 page_start = page_offset(pages[0]); 1088 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; 1089 1090 lock_extent_bits(&BTRFS_I(inode)->io_tree, 1091 page_start, page_end - 1, 0, &cached_state); 1092 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 1093 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 1094 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, 1095 &cached_state, GFP_NOFS); 1096 1097 if (i_done != page_cnt) { 1098 spin_lock(&BTRFS_I(inode)->lock); 1099 BTRFS_I(inode)->outstanding_extents++; 1100 spin_unlock(&BTRFS_I(inode)->lock); 1101 btrfs_delalloc_release_space(inode, 1102 (page_cnt - i_done) << PAGE_CACHE_SHIFT); 1103 } 1104 1105 1106 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, 1107 &cached_state, GFP_NOFS); 1108 1109 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 1110 page_start, page_end - 1, &cached_state, 1111 GFP_NOFS); 1112 1113 for (i = 0; i < i_done; i++) { 1114 clear_page_dirty_for_io(pages[i]); 1115 ClearPageChecked(pages[i]); 1116 set_page_extent_mapped(pages[i]); 1117 set_page_dirty(pages[i]); 1118 unlock_page(pages[i]); 1119 page_cache_release(pages[i]); 1120 } 1121 return i_done; 1122 out: 1123 for (i = 0; i < i_done; i++) { 1124 unlock_page(pages[i]); 1125 page_cache_release(pages[i]); 1126 } 1127 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT); 1128 return ret; 1129 1130 } 1131 1132 int btrfs_defrag_file(struct inode *inode, struct file *file, 1133 struct btrfs_ioctl_defrag_range_args *range, 1134 u64 newer_than, unsigned long max_to_defrag) 1135 { 1136 struct btrfs_root *root = BTRFS_I(inode)->root; 1137 struct file_ra_state *ra = NULL; 1138 unsigned long last_index; 1139 u64 isize = i_size_read(inode); 1140 u64 last_len = 0; 1141 u64 skip = 0; 1142 u64 defrag_end = 0; 1143 u64 newer_off = range->start; 1144 unsigned long i; 1145 unsigned long ra_index = 0; 1146 int ret; 1147 int defrag_count = 0; 1148 int compress_type = BTRFS_COMPRESS_ZLIB; 1149 int extent_thresh = range->extent_thresh; 1150 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; 1151 int cluster = max_cluster; 1152 u64 new_align = ~((u64)128 * 1024 - 1); 1153 struct page **pages = NULL; 1154 1155 if (extent_thresh == 0) 1156 extent_thresh = 256 * 1024; 1157 1158 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1159 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1160 return -EINVAL; 1161 if (range->compress_type) 1162 compress_type = range->compress_type; 1163 } 1164 1165 if (isize == 0) 1166 return 0; 1167 1168 /* 1169 * if we were not given a file, allocate a readahead 1170 * context 1171 */ 1172 if (!file) { 1173 ra = kzalloc(sizeof(*ra), GFP_NOFS); 1174 if (!ra) 1175 return -ENOMEM; 1176 file_ra_state_init(ra, inode->i_mapping); 1177 } else { 1178 ra = &file->f_ra; 1179 } 1180 1181 pages = kmalloc(sizeof(struct page *) * max_cluster, 1182 GFP_NOFS); 1183 if (!pages) { 1184 ret = -ENOMEM; 1185 goto out_ra; 1186 } 1187 1188 /* find the last page to defrag */ 1189 if (range->start + range->len > range->start) { 1190 last_index = min_t(u64, isize - 1, 1191 range->start + range->len - 1) >> PAGE_CACHE_SHIFT; 1192 } else { 1193 last_index = (isize - 1) >> PAGE_CACHE_SHIFT; 1194 } 1195 1196 if (newer_than) { 1197 ret = find_new_extents(root, inode, newer_than, 1198 &newer_off, 64 * 1024); 1199 if (!ret) { 1200 range->start = newer_off; 1201 /* 1202 * we always align our defrag to help keep 1203 * the extents in the file evenly spaced 1204 */ 1205 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1206 } else 1207 goto out_ra; 1208 } else { 1209 i = range->start >> PAGE_CACHE_SHIFT; 1210 } 1211 if (!max_to_defrag) 1212 max_to_defrag = last_index + 1; 1213 1214 /* 1215 * make writeback starts from i, so the defrag range can be 1216 * written sequentially. 1217 */ 1218 if (i < inode->i_mapping->writeback_index) 1219 inode->i_mapping->writeback_index = i; 1220 1221 while (i <= last_index && defrag_count < max_to_defrag && 1222 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> 1223 PAGE_CACHE_SHIFT)) { 1224 /* 1225 * make sure we stop running if someone unmounts 1226 * the FS 1227 */ 1228 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1229 break; 1230 1231 if (btrfs_defrag_cancelled(root->fs_info)) { 1232 printk(KERN_DEBUG "btrfs: defrag_file cancelled\n"); 1233 ret = -EAGAIN; 1234 break; 1235 } 1236 1237 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, 1238 extent_thresh, &last_len, &skip, 1239 &defrag_end, range->flags & 1240 BTRFS_DEFRAG_RANGE_COMPRESS)) { 1241 unsigned long next; 1242 /* 1243 * the should_defrag function tells us how much to skip 1244 * bump our counter by the suggested amount 1245 */ 1246 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 1247 i = max(i + 1, next); 1248 continue; 1249 } 1250 1251 if (!newer_than) { 1252 cluster = (PAGE_CACHE_ALIGN(defrag_end) >> 1253 PAGE_CACHE_SHIFT) - i; 1254 cluster = min(cluster, max_cluster); 1255 } else { 1256 cluster = max_cluster; 1257 } 1258 1259 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) 1260 BTRFS_I(inode)->force_compress = compress_type; 1261 1262 if (i + cluster > ra_index) { 1263 ra_index = max(i, ra_index); 1264 btrfs_force_ra(inode->i_mapping, ra, file, ra_index, 1265 cluster); 1266 ra_index += max_cluster; 1267 } 1268 1269 mutex_lock(&inode->i_mutex); 1270 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1271 if (ret < 0) { 1272 mutex_unlock(&inode->i_mutex); 1273 goto out_ra; 1274 } 1275 1276 defrag_count += ret; 1277 balance_dirty_pages_ratelimited(inode->i_mapping); 1278 mutex_unlock(&inode->i_mutex); 1279 1280 if (newer_than) { 1281 if (newer_off == (u64)-1) 1282 break; 1283 1284 if (ret > 0) 1285 i += ret; 1286 1287 newer_off = max(newer_off + 1, 1288 (u64)i << PAGE_CACHE_SHIFT); 1289 1290 ret = find_new_extents(root, inode, 1291 newer_than, &newer_off, 1292 64 * 1024); 1293 if (!ret) { 1294 range->start = newer_off; 1295 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1296 } else { 1297 break; 1298 } 1299 } else { 1300 if (ret > 0) { 1301 i += ret; 1302 last_len += ret << PAGE_CACHE_SHIFT; 1303 } else { 1304 i++; 1305 last_len = 0; 1306 } 1307 } 1308 } 1309 1310 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) 1311 filemap_flush(inode->i_mapping); 1312 1313 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 1314 /* the filemap_flush will queue IO into the worker threads, but 1315 * we have to make sure the IO is actually started and that 1316 * ordered extents get created before we return 1317 */ 1318 atomic_inc(&root->fs_info->async_submit_draining); 1319 while (atomic_read(&root->fs_info->nr_async_submits) || 1320 atomic_read(&root->fs_info->async_delalloc_pages)) { 1321 wait_event(root->fs_info->async_submit_wait, 1322 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 1323 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 1324 } 1325 atomic_dec(&root->fs_info->async_submit_draining); 1326 1327 mutex_lock(&inode->i_mutex); 1328 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; 1329 mutex_unlock(&inode->i_mutex); 1330 } 1331 1332 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1333 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO); 1334 } 1335 1336 ret = defrag_count; 1337 1338 out_ra: 1339 if (!file) 1340 kfree(ra); 1341 kfree(pages); 1342 return ret; 1343 } 1344 1345 static noinline int btrfs_ioctl_resize(struct file *file, 1346 void __user *arg) 1347 { 1348 u64 new_size; 1349 u64 old_size; 1350 u64 devid = 1; 1351 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 1352 struct btrfs_ioctl_vol_args *vol_args; 1353 struct btrfs_trans_handle *trans; 1354 struct btrfs_device *device = NULL; 1355 char *sizestr; 1356 char *devstr = NULL; 1357 int ret = 0; 1358 int mod = 0; 1359 1360 if (!capable(CAP_SYS_ADMIN)) 1361 return -EPERM; 1362 1363 ret = mnt_want_write_file(file); 1364 if (ret) 1365 return ret; 1366 1367 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1368 1)) { 1369 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); 1370 mnt_drop_write_file(file); 1371 return -EINVAL; 1372 } 1373 1374 mutex_lock(&root->fs_info->volume_mutex); 1375 vol_args = memdup_user(arg, sizeof(*vol_args)); 1376 if (IS_ERR(vol_args)) { 1377 ret = PTR_ERR(vol_args); 1378 goto out; 1379 } 1380 1381 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1382 1383 sizestr = vol_args->name; 1384 devstr = strchr(sizestr, ':'); 1385 if (devstr) { 1386 char *end; 1387 sizestr = devstr + 1; 1388 *devstr = '\0'; 1389 devstr = vol_args->name; 1390 devid = simple_strtoull(devstr, &end, 10); 1391 if (!devid) { 1392 ret = -EINVAL; 1393 goto out_free; 1394 } 1395 printk(KERN_INFO "btrfs: resizing devid %llu\n", 1396 (unsigned long long)devid); 1397 } 1398 1399 device = btrfs_find_device(root->fs_info, devid, NULL, NULL); 1400 if (!device) { 1401 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n", 1402 (unsigned long long)devid); 1403 ret = -ENODEV; 1404 goto out_free; 1405 } 1406 1407 if (!device->writeable) { 1408 printk(KERN_INFO "btrfs: resizer unable to apply on " 1409 "readonly device %llu\n", 1410 (unsigned long long)devid); 1411 ret = -EPERM; 1412 goto out_free; 1413 } 1414 1415 if (!strcmp(sizestr, "max")) 1416 new_size = device->bdev->bd_inode->i_size; 1417 else { 1418 if (sizestr[0] == '-') { 1419 mod = -1; 1420 sizestr++; 1421 } else if (sizestr[0] == '+') { 1422 mod = 1; 1423 sizestr++; 1424 } 1425 new_size = memparse(sizestr, NULL); 1426 if (new_size == 0) { 1427 ret = -EINVAL; 1428 goto out_free; 1429 } 1430 } 1431 1432 if (device->is_tgtdev_for_dev_replace) { 1433 ret = -EPERM; 1434 goto out_free; 1435 } 1436 1437 old_size = device->total_bytes; 1438 1439 if (mod < 0) { 1440 if (new_size > old_size) { 1441 ret = -EINVAL; 1442 goto out_free; 1443 } 1444 new_size = old_size - new_size; 1445 } else if (mod > 0) { 1446 new_size = old_size + new_size; 1447 } 1448 1449 if (new_size < 256 * 1024 * 1024) { 1450 ret = -EINVAL; 1451 goto out_free; 1452 } 1453 if (new_size > device->bdev->bd_inode->i_size) { 1454 ret = -EFBIG; 1455 goto out_free; 1456 } 1457 1458 do_div(new_size, root->sectorsize); 1459 new_size *= root->sectorsize; 1460 1461 printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n", 1462 rcu_str_deref(device->name), 1463 (unsigned long long)new_size); 1464 1465 if (new_size > old_size) { 1466 trans = btrfs_start_transaction(root, 0); 1467 if (IS_ERR(trans)) { 1468 ret = PTR_ERR(trans); 1469 goto out_free; 1470 } 1471 ret = btrfs_grow_device(trans, device, new_size); 1472 btrfs_commit_transaction(trans, root); 1473 } else if (new_size < old_size) { 1474 ret = btrfs_shrink_device(device, new_size); 1475 } /* equal, nothing need to do */ 1476 1477 out_free: 1478 kfree(vol_args); 1479 out: 1480 mutex_unlock(&root->fs_info->volume_mutex); 1481 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 1482 mnt_drop_write_file(file); 1483 return ret; 1484 } 1485 1486 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1487 char *name, unsigned long fd, int subvol, 1488 u64 *transid, bool readonly, 1489 struct btrfs_qgroup_inherit *inherit) 1490 { 1491 int namelen; 1492 int ret = 0; 1493 1494 ret = mnt_want_write_file(file); 1495 if (ret) 1496 goto out; 1497 1498 namelen = strlen(name); 1499 if (strchr(name, '/')) { 1500 ret = -EINVAL; 1501 goto out_drop_write; 1502 } 1503 1504 if (name[0] == '.' && 1505 (namelen == 1 || (name[1] == '.' && namelen == 2))) { 1506 ret = -EEXIST; 1507 goto out_drop_write; 1508 } 1509 1510 if (subvol) { 1511 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1512 NULL, transid, readonly, inherit); 1513 } else { 1514 struct fd src = fdget(fd); 1515 struct inode *src_inode; 1516 if (!src.file) { 1517 ret = -EINVAL; 1518 goto out_drop_write; 1519 } 1520 1521 src_inode = file_inode(src.file); 1522 if (src_inode->i_sb != file_inode(file)->i_sb) { 1523 printk(KERN_INFO "btrfs: Snapshot src from " 1524 "another FS\n"); 1525 ret = -EINVAL; 1526 } else { 1527 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1528 BTRFS_I(src_inode)->root, 1529 transid, readonly, inherit); 1530 } 1531 fdput(src); 1532 } 1533 out_drop_write: 1534 mnt_drop_write_file(file); 1535 out: 1536 return ret; 1537 } 1538 1539 static noinline int btrfs_ioctl_snap_create(struct file *file, 1540 void __user *arg, int subvol) 1541 { 1542 struct btrfs_ioctl_vol_args *vol_args; 1543 int ret; 1544 1545 vol_args = memdup_user(arg, sizeof(*vol_args)); 1546 if (IS_ERR(vol_args)) 1547 return PTR_ERR(vol_args); 1548 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1549 1550 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1551 vol_args->fd, subvol, 1552 NULL, false, NULL); 1553 1554 kfree(vol_args); 1555 return ret; 1556 } 1557 1558 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1559 void __user *arg, int subvol) 1560 { 1561 struct btrfs_ioctl_vol_args_v2 *vol_args; 1562 int ret; 1563 u64 transid = 0; 1564 u64 *ptr = NULL; 1565 bool readonly = false; 1566 struct btrfs_qgroup_inherit *inherit = NULL; 1567 1568 vol_args = memdup_user(arg, sizeof(*vol_args)); 1569 if (IS_ERR(vol_args)) 1570 return PTR_ERR(vol_args); 1571 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1572 1573 if (vol_args->flags & 1574 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | 1575 BTRFS_SUBVOL_QGROUP_INHERIT)) { 1576 ret = -EOPNOTSUPP; 1577 goto out; 1578 } 1579 1580 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1581 ptr = &transid; 1582 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1583 readonly = true; 1584 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { 1585 if (vol_args->size > PAGE_CACHE_SIZE) { 1586 ret = -EINVAL; 1587 goto out; 1588 } 1589 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); 1590 if (IS_ERR(inherit)) { 1591 ret = PTR_ERR(inherit); 1592 goto out; 1593 } 1594 } 1595 1596 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1597 vol_args->fd, subvol, ptr, 1598 readonly, inherit); 1599 1600 if (ret == 0 && ptr && 1601 copy_to_user(arg + 1602 offsetof(struct btrfs_ioctl_vol_args_v2, 1603 transid), ptr, sizeof(*ptr))) 1604 ret = -EFAULT; 1605 out: 1606 kfree(vol_args); 1607 kfree(inherit); 1608 return ret; 1609 } 1610 1611 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1612 void __user *arg) 1613 { 1614 struct inode *inode = file_inode(file); 1615 struct btrfs_root *root = BTRFS_I(inode)->root; 1616 int ret = 0; 1617 u64 flags = 0; 1618 1619 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1620 return -EINVAL; 1621 1622 down_read(&root->fs_info->subvol_sem); 1623 if (btrfs_root_readonly(root)) 1624 flags |= BTRFS_SUBVOL_RDONLY; 1625 up_read(&root->fs_info->subvol_sem); 1626 1627 if (copy_to_user(arg, &flags, sizeof(flags))) 1628 ret = -EFAULT; 1629 1630 return ret; 1631 } 1632 1633 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1634 void __user *arg) 1635 { 1636 struct inode *inode = file_inode(file); 1637 struct btrfs_root *root = BTRFS_I(inode)->root; 1638 struct btrfs_trans_handle *trans; 1639 u64 root_flags; 1640 u64 flags; 1641 int ret = 0; 1642 1643 ret = mnt_want_write_file(file); 1644 if (ret) 1645 goto out; 1646 1647 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 1648 ret = -EINVAL; 1649 goto out_drop_write; 1650 } 1651 1652 if (copy_from_user(&flags, arg, sizeof(flags))) { 1653 ret = -EFAULT; 1654 goto out_drop_write; 1655 } 1656 1657 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) { 1658 ret = -EINVAL; 1659 goto out_drop_write; 1660 } 1661 1662 if (flags & ~BTRFS_SUBVOL_RDONLY) { 1663 ret = -EOPNOTSUPP; 1664 goto out_drop_write; 1665 } 1666 1667 if (!inode_owner_or_capable(inode)) { 1668 ret = -EACCES; 1669 goto out_drop_write; 1670 } 1671 1672 down_write(&root->fs_info->subvol_sem); 1673 1674 /* nothing to do */ 1675 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1676 goto out_drop_sem; 1677 1678 root_flags = btrfs_root_flags(&root->root_item); 1679 if (flags & BTRFS_SUBVOL_RDONLY) 1680 btrfs_set_root_flags(&root->root_item, 1681 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1682 else 1683 btrfs_set_root_flags(&root->root_item, 1684 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1685 1686 trans = btrfs_start_transaction(root, 1); 1687 if (IS_ERR(trans)) { 1688 ret = PTR_ERR(trans); 1689 goto out_reset; 1690 } 1691 1692 ret = btrfs_update_root(trans, root->fs_info->tree_root, 1693 &root->root_key, &root->root_item); 1694 1695 btrfs_commit_transaction(trans, root); 1696 out_reset: 1697 if (ret) 1698 btrfs_set_root_flags(&root->root_item, root_flags); 1699 out_drop_sem: 1700 up_write(&root->fs_info->subvol_sem); 1701 out_drop_write: 1702 mnt_drop_write_file(file); 1703 out: 1704 return ret; 1705 } 1706 1707 /* 1708 * helper to check if the subvolume references other subvolumes 1709 */ 1710 static noinline int may_destroy_subvol(struct btrfs_root *root) 1711 { 1712 struct btrfs_path *path; 1713 struct btrfs_key key; 1714 int ret; 1715 1716 path = btrfs_alloc_path(); 1717 if (!path) 1718 return -ENOMEM; 1719 1720 key.objectid = root->root_key.objectid; 1721 key.type = BTRFS_ROOT_REF_KEY; 1722 key.offset = (u64)-1; 1723 1724 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, 1725 &key, path, 0, 0); 1726 if (ret < 0) 1727 goto out; 1728 BUG_ON(ret == 0); 1729 1730 ret = 0; 1731 if (path->slots[0] > 0) { 1732 path->slots[0]--; 1733 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 1734 if (key.objectid == root->root_key.objectid && 1735 key.type == BTRFS_ROOT_REF_KEY) 1736 ret = -ENOTEMPTY; 1737 } 1738 out: 1739 btrfs_free_path(path); 1740 return ret; 1741 } 1742 1743 static noinline int key_in_sk(struct btrfs_key *key, 1744 struct btrfs_ioctl_search_key *sk) 1745 { 1746 struct btrfs_key test; 1747 int ret; 1748 1749 test.objectid = sk->min_objectid; 1750 test.type = sk->min_type; 1751 test.offset = sk->min_offset; 1752 1753 ret = btrfs_comp_cpu_keys(key, &test); 1754 if (ret < 0) 1755 return 0; 1756 1757 test.objectid = sk->max_objectid; 1758 test.type = sk->max_type; 1759 test.offset = sk->max_offset; 1760 1761 ret = btrfs_comp_cpu_keys(key, &test); 1762 if (ret > 0) 1763 return 0; 1764 return 1; 1765 } 1766 1767 static noinline int copy_to_sk(struct btrfs_root *root, 1768 struct btrfs_path *path, 1769 struct btrfs_key *key, 1770 struct btrfs_ioctl_search_key *sk, 1771 char *buf, 1772 unsigned long *sk_offset, 1773 int *num_found) 1774 { 1775 u64 found_transid; 1776 struct extent_buffer *leaf; 1777 struct btrfs_ioctl_search_header sh; 1778 unsigned long item_off; 1779 unsigned long item_len; 1780 int nritems; 1781 int i; 1782 int slot; 1783 int ret = 0; 1784 1785 leaf = path->nodes[0]; 1786 slot = path->slots[0]; 1787 nritems = btrfs_header_nritems(leaf); 1788 1789 if (btrfs_header_generation(leaf) > sk->max_transid) { 1790 i = nritems; 1791 goto advance_key; 1792 } 1793 found_transid = btrfs_header_generation(leaf); 1794 1795 for (i = slot; i < nritems; i++) { 1796 item_off = btrfs_item_ptr_offset(leaf, i); 1797 item_len = btrfs_item_size_nr(leaf, i); 1798 1799 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) 1800 item_len = 0; 1801 1802 if (sizeof(sh) + item_len + *sk_offset > 1803 BTRFS_SEARCH_ARGS_BUFSIZE) { 1804 ret = 1; 1805 goto overflow; 1806 } 1807 1808 btrfs_item_key_to_cpu(leaf, key, i); 1809 if (!key_in_sk(key, sk)) 1810 continue; 1811 1812 sh.objectid = key->objectid; 1813 sh.offset = key->offset; 1814 sh.type = key->type; 1815 sh.len = item_len; 1816 sh.transid = found_transid; 1817 1818 /* copy search result header */ 1819 memcpy(buf + *sk_offset, &sh, sizeof(sh)); 1820 *sk_offset += sizeof(sh); 1821 1822 if (item_len) { 1823 char *p = buf + *sk_offset; 1824 /* copy the item */ 1825 read_extent_buffer(leaf, p, 1826 item_off, item_len); 1827 *sk_offset += item_len; 1828 } 1829 (*num_found)++; 1830 1831 if (*num_found >= sk->nr_items) 1832 break; 1833 } 1834 advance_key: 1835 ret = 0; 1836 if (key->offset < (u64)-1 && key->offset < sk->max_offset) 1837 key->offset++; 1838 else if (key->type < (u8)-1 && key->type < sk->max_type) { 1839 key->offset = 0; 1840 key->type++; 1841 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { 1842 key->offset = 0; 1843 key->type = 0; 1844 key->objectid++; 1845 } else 1846 ret = 1; 1847 overflow: 1848 return ret; 1849 } 1850 1851 static noinline int search_ioctl(struct inode *inode, 1852 struct btrfs_ioctl_search_args *args) 1853 { 1854 struct btrfs_root *root; 1855 struct btrfs_key key; 1856 struct btrfs_key max_key; 1857 struct btrfs_path *path; 1858 struct btrfs_ioctl_search_key *sk = &args->key; 1859 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; 1860 int ret; 1861 int num_found = 0; 1862 unsigned long sk_offset = 0; 1863 1864 path = btrfs_alloc_path(); 1865 if (!path) 1866 return -ENOMEM; 1867 1868 if (sk->tree_id == 0) { 1869 /* search the root of the inode that was passed */ 1870 root = BTRFS_I(inode)->root; 1871 } else { 1872 key.objectid = sk->tree_id; 1873 key.type = BTRFS_ROOT_ITEM_KEY; 1874 key.offset = (u64)-1; 1875 root = btrfs_read_fs_root_no_name(info, &key); 1876 if (IS_ERR(root)) { 1877 printk(KERN_ERR "could not find root %llu\n", 1878 sk->tree_id); 1879 btrfs_free_path(path); 1880 return -ENOENT; 1881 } 1882 } 1883 1884 key.objectid = sk->min_objectid; 1885 key.type = sk->min_type; 1886 key.offset = sk->min_offset; 1887 1888 max_key.objectid = sk->max_objectid; 1889 max_key.type = sk->max_type; 1890 max_key.offset = sk->max_offset; 1891 1892 path->keep_locks = 1; 1893 1894 while(1) { 1895 ret = btrfs_search_forward(root, &key, &max_key, path, 1896 sk->min_transid); 1897 if (ret != 0) { 1898 if (ret > 0) 1899 ret = 0; 1900 goto err; 1901 } 1902 ret = copy_to_sk(root, path, &key, sk, args->buf, 1903 &sk_offset, &num_found); 1904 btrfs_release_path(path); 1905 if (ret || num_found >= sk->nr_items) 1906 break; 1907 1908 } 1909 ret = 0; 1910 err: 1911 sk->nr_items = num_found; 1912 btrfs_free_path(path); 1913 return ret; 1914 } 1915 1916 static noinline int btrfs_ioctl_tree_search(struct file *file, 1917 void __user *argp) 1918 { 1919 struct btrfs_ioctl_search_args *args; 1920 struct inode *inode; 1921 int ret; 1922 1923 if (!capable(CAP_SYS_ADMIN)) 1924 return -EPERM; 1925 1926 args = memdup_user(argp, sizeof(*args)); 1927 if (IS_ERR(args)) 1928 return PTR_ERR(args); 1929 1930 inode = file_inode(file); 1931 ret = search_ioctl(inode, args); 1932 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1933 ret = -EFAULT; 1934 kfree(args); 1935 return ret; 1936 } 1937 1938 /* 1939 * Search INODE_REFs to identify path name of 'dirid' directory 1940 * in a 'tree_id' tree. and sets path name to 'name'. 1941 */ 1942 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 1943 u64 tree_id, u64 dirid, char *name) 1944 { 1945 struct btrfs_root *root; 1946 struct btrfs_key key; 1947 char *ptr; 1948 int ret = -1; 1949 int slot; 1950 int len; 1951 int total_len = 0; 1952 struct btrfs_inode_ref *iref; 1953 struct extent_buffer *l; 1954 struct btrfs_path *path; 1955 1956 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 1957 name[0]='\0'; 1958 return 0; 1959 } 1960 1961 path = btrfs_alloc_path(); 1962 if (!path) 1963 return -ENOMEM; 1964 1965 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; 1966 1967 key.objectid = tree_id; 1968 key.type = BTRFS_ROOT_ITEM_KEY; 1969 key.offset = (u64)-1; 1970 root = btrfs_read_fs_root_no_name(info, &key); 1971 if (IS_ERR(root)) { 1972 printk(KERN_ERR "could not find root %llu\n", tree_id); 1973 ret = -ENOENT; 1974 goto out; 1975 } 1976 1977 key.objectid = dirid; 1978 key.type = BTRFS_INODE_REF_KEY; 1979 key.offset = (u64)-1; 1980 1981 while(1) { 1982 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1983 if (ret < 0) 1984 goto out; 1985 1986 l = path->nodes[0]; 1987 slot = path->slots[0]; 1988 if (ret > 0 && slot > 0) 1989 slot--; 1990 btrfs_item_key_to_cpu(l, &key, slot); 1991 1992 if (ret > 0 && (key.objectid != dirid || 1993 key.type != BTRFS_INODE_REF_KEY)) { 1994 ret = -ENOENT; 1995 goto out; 1996 } 1997 1998 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 1999 len = btrfs_inode_ref_name_len(l, iref); 2000 ptr -= len + 1; 2001 total_len += len + 1; 2002 if (ptr < name) 2003 goto out; 2004 2005 *(ptr + len) = '/'; 2006 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len); 2007 2008 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 2009 break; 2010 2011 btrfs_release_path(path); 2012 key.objectid = key.offset; 2013 key.offset = (u64)-1; 2014 dirid = key.objectid; 2015 } 2016 if (ptr < name) 2017 goto out; 2018 memmove(name, ptr, total_len); 2019 name[total_len]='\0'; 2020 ret = 0; 2021 out: 2022 btrfs_free_path(path); 2023 return ret; 2024 } 2025 2026 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 2027 void __user *argp) 2028 { 2029 struct btrfs_ioctl_ino_lookup_args *args; 2030 struct inode *inode; 2031 int ret; 2032 2033 if (!capable(CAP_SYS_ADMIN)) 2034 return -EPERM; 2035 2036 args = memdup_user(argp, sizeof(*args)); 2037 if (IS_ERR(args)) 2038 return PTR_ERR(args); 2039 2040 inode = file_inode(file); 2041 2042 if (args->treeid == 0) 2043 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 2044 2045 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 2046 args->treeid, args->objectid, 2047 args->name); 2048 2049 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 2050 ret = -EFAULT; 2051 2052 kfree(args); 2053 return ret; 2054 } 2055 2056 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 2057 void __user *arg) 2058 { 2059 struct dentry *parent = fdentry(file); 2060 struct dentry *dentry; 2061 struct inode *dir = parent->d_inode; 2062 struct inode *inode; 2063 struct btrfs_root *root = BTRFS_I(dir)->root; 2064 struct btrfs_root *dest = NULL; 2065 struct btrfs_ioctl_vol_args *vol_args; 2066 struct btrfs_trans_handle *trans; 2067 struct btrfs_block_rsv block_rsv; 2068 u64 qgroup_reserved; 2069 int namelen; 2070 int ret; 2071 int err = 0; 2072 2073 vol_args = memdup_user(arg, sizeof(*vol_args)); 2074 if (IS_ERR(vol_args)) 2075 return PTR_ERR(vol_args); 2076 2077 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2078 namelen = strlen(vol_args->name); 2079 if (strchr(vol_args->name, '/') || 2080 strncmp(vol_args->name, "..", namelen) == 0) { 2081 err = -EINVAL; 2082 goto out; 2083 } 2084 2085 err = mnt_want_write_file(file); 2086 if (err) 2087 goto out; 2088 2089 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 2090 dentry = lookup_one_len(vol_args->name, parent, namelen); 2091 if (IS_ERR(dentry)) { 2092 err = PTR_ERR(dentry); 2093 goto out_unlock_dir; 2094 } 2095 2096 if (!dentry->d_inode) { 2097 err = -ENOENT; 2098 goto out_dput; 2099 } 2100 2101 inode = dentry->d_inode; 2102 dest = BTRFS_I(inode)->root; 2103 if (!capable(CAP_SYS_ADMIN)){ 2104 /* 2105 * Regular user. Only allow this with a special mount 2106 * option, when the user has write+exec access to the 2107 * subvol root, and when rmdir(2) would have been 2108 * allowed. 2109 * 2110 * Note that this is _not_ check that the subvol is 2111 * empty or doesn't contain data that we wouldn't 2112 * otherwise be able to delete. 2113 * 2114 * Users who want to delete empty subvols should try 2115 * rmdir(2). 2116 */ 2117 err = -EPERM; 2118 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 2119 goto out_dput; 2120 2121 /* 2122 * Do not allow deletion if the parent dir is the same 2123 * as the dir to be deleted. That means the ioctl 2124 * must be called on the dentry referencing the root 2125 * of the subvol, not a random directory contained 2126 * within it. 2127 */ 2128 err = -EINVAL; 2129 if (root == dest) 2130 goto out_dput; 2131 2132 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 2133 if (err) 2134 goto out_dput; 2135 } 2136 2137 /* check if subvolume may be deleted by a user */ 2138 err = btrfs_may_delete(dir, dentry, 1); 2139 if (err) 2140 goto out_dput; 2141 2142 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 2143 err = -EINVAL; 2144 goto out_dput; 2145 } 2146 2147 mutex_lock(&inode->i_mutex); 2148 err = d_invalidate(dentry); 2149 if (err) 2150 goto out_unlock; 2151 2152 down_write(&root->fs_info->subvol_sem); 2153 2154 err = may_destroy_subvol(dest); 2155 if (err) 2156 goto out_up_write; 2157 2158 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); 2159 /* 2160 * One for dir inode, two for dir entries, two for root 2161 * ref/backref. 2162 */ 2163 err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 2164 5, &qgroup_reserved); 2165 if (err) 2166 goto out_up_write; 2167 2168 trans = btrfs_start_transaction(root, 0); 2169 if (IS_ERR(trans)) { 2170 err = PTR_ERR(trans); 2171 goto out_release; 2172 } 2173 trans->block_rsv = &block_rsv; 2174 trans->bytes_reserved = block_rsv.size; 2175 2176 ret = btrfs_unlink_subvol(trans, root, dir, 2177 dest->root_key.objectid, 2178 dentry->d_name.name, 2179 dentry->d_name.len); 2180 if (ret) { 2181 err = ret; 2182 btrfs_abort_transaction(trans, root, ret); 2183 goto out_end_trans; 2184 } 2185 2186 btrfs_record_root_in_trans(trans, dest); 2187 2188 memset(&dest->root_item.drop_progress, 0, 2189 sizeof(dest->root_item.drop_progress)); 2190 dest->root_item.drop_level = 0; 2191 btrfs_set_root_refs(&dest->root_item, 0); 2192 2193 if (!xchg(&dest->orphan_item_inserted, 1)) { 2194 ret = btrfs_insert_orphan_item(trans, 2195 root->fs_info->tree_root, 2196 dest->root_key.objectid); 2197 if (ret) { 2198 btrfs_abort_transaction(trans, root, ret); 2199 err = ret; 2200 goto out_end_trans; 2201 } 2202 } 2203 out_end_trans: 2204 trans->block_rsv = NULL; 2205 trans->bytes_reserved = 0; 2206 ret = btrfs_end_transaction(trans, root); 2207 if (ret && !err) 2208 err = ret; 2209 inode->i_flags |= S_DEAD; 2210 out_release: 2211 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); 2212 out_up_write: 2213 up_write(&root->fs_info->subvol_sem); 2214 out_unlock: 2215 mutex_unlock(&inode->i_mutex); 2216 if (!err) { 2217 shrink_dcache_sb(root->fs_info->sb); 2218 btrfs_invalidate_inodes(dest); 2219 d_delete(dentry); 2220 2221 /* the last ref */ 2222 if (dest->cache_inode) { 2223 iput(dest->cache_inode); 2224 dest->cache_inode = NULL; 2225 } 2226 } 2227 out_dput: 2228 dput(dentry); 2229 out_unlock_dir: 2230 mutex_unlock(&dir->i_mutex); 2231 mnt_drop_write_file(file); 2232 out: 2233 kfree(vol_args); 2234 return err; 2235 } 2236 2237 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 2238 { 2239 struct inode *inode = file_inode(file); 2240 struct btrfs_root *root = BTRFS_I(inode)->root; 2241 struct btrfs_ioctl_defrag_range_args *range; 2242 int ret; 2243 2244 ret = mnt_want_write_file(file); 2245 if (ret) 2246 return ret; 2247 2248 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 2249 1)) { 2250 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); 2251 mnt_drop_write_file(file); 2252 return -EINVAL; 2253 } 2254 2255 if (btrfs_root_readonly(root)) { 2256 ret = -EROFS; 2257 goto out; 2258 } 2259 2260 switch (inode->i_mode & S_IFMT) { 2261 case S_IFDIR: 2262 if (!capable(CAP_SYS_ADMIN)) { 2263 ret = -EPERM; 2264 goto out; 2265 } 2266 ret = btrfs_defrag_root(root); 2267 if (ret) 2268 goto out; 2269 ret = btrfs_defrag_root(root->fs_info->extent_root); 2270 break; 2271 case S_IFREG: 2272 if (!(file->f_mode & FMODE_WRITE)) { 2273 ret = -EINVAL; 2274 goto out; 2275 } 2276 2277 range = kzalloc(sizeof(*range), GFP_KERNEL); 2278 if (!range) { 2279 ret = -ENOMEM; 2280 goto out; 2281 } 2282 2283 if (argp) { 2284 if (copy_from_user(range, argp, 2285 sizeof(*range))) { 2286 ret = -EFAULT; 2287 kfree(range); 2288 goto out; 2289 } 2290 /* compression requires us to start the IO */ 2291 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2292 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2293 range->extent_thresh = (u32)-1; 2294 } 2295 } else { 2296 /* the rest are all set to zero by kzalloc */ 2297 range->len = (u64)-1; 2298 } 2299 ret = btrfs_defrag_file(file_inode(file), file, 2300 range, 0, 0); 2301 if (ret > 0) 2302 ret = 0; 2303 kfree(range); 2304 break; 2305 default: 2306 ret = -EINVAL; 2307 } 2308 out: 2309 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 2310 mnt_drop_write_file(file); 2311 return ret; 2312 } 2313 2314 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 2315 { 2316 struct btrfs_ioctl_vol_args *vol_args; 2317 int ret; 2318 2319 if (!capable(CAP_SYS_ADMIN)) 2320 return -EPERM; 2321 2322 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 2323 1)) { 2324 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); 2325 return -EINVAL; 2326 } 2327 2328 mutex_lock(&root->fs_info->volume_mutex); 2329 vol_args = memdup_user(arg, sizeof(*vol_args)); 2330 if (IS_ERR(vol_args)) { 2331 ret = PTR_ERR(vol_args); 2332 goto out; 2333 } 2334 2335 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2336 ret = btrfs_init_new_device(root, vol_args->name); 2337 2338 kfree(vol_args); 2339 out: 2340 mutex_unlock(&root->fs_info->volume_mutex); 2341 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 2342 return ret; 2343 } 2344 2345 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) 2346 { 2347 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 2348 struct btrfs_ioctl_vol_args *vol_args; 2349 int ret; 2350 2351 if (!capable(CAP_SYS_ADMIN)) 2352 return -EPERM; 2353 2354 ret = mnt_want_write_file(file); 2355 if (ret) 2356 return ret; 2357 2358 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 2359 1)) { 2360 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); 2361 mnt_drop_write_file(file); 2362 return -EINVAL; 2363 } 2364 2365 mutex_lock(&root->fs_info->volume_mutex); 2366 vol_args = memdup_user(arg, sizeof(*vol_args)); 2367 if (IS_ERR(vol_args)) { 2368 ret = PTR_ERR(vol_args); 2369 goto out; 2370 } 2371 2372 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2373 ret = btrfs_rm_device(root, vol_args->name); 2374 2375 kfree(vol_args); 2376 out: 2377 mutex_unlock(&root->fs_info->volume_mutex); 2378 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 2379 mnt_drop_write_file(file); 2380 return ret; 2381 } 2382 2383 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) 2384 { 2385 struct btrfs_ioctl_fs_info_args *fi_args; 2386 struct btrfs_device *device; 2387 struct btrfs_device *next; 2388 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2389 int ret = 0; 2390 2391 if (!capable(CAP_SYS_ADMIN)) 2392 return -EPERM; 2393 2394 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 2395 if (!fi_args) 2396 return -ENOMEM; 2397 2398 fi_args->num_devices = fs_devices->num_devices; 2399 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); 2400 2401 mutex_lock(&fs_devices->device_list_mutex); 2402 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 2403 if (device->devid > fi_args->max_id) 2404 fi_args->max_id = device->devid; 2405 } 2406 mutex_unlock(&fs_devices->device_list_mutex); 2407 2408 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 2409 ret = -EFAULT; 2410 2411 kfree(fi_args); 2412 return ret; 2413 } 2414 2415 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) 2416 { 2417 struct btrfs_ioctl_dev_info_args *di_args; 2418 struct btrfs_device *dev; 2419 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2420 int ret = 0; 2421 char *s_uuid = NULL; 2422 char empty_uuid[BTRFS_UUID_SIZE] = {0}; 2423 2424 if (!capable(CAP_SYS_ADMIN)) 2425 return -EPERM; 2426 2427 di_args = memdup_user(arg, sizeof(*di_args)); 2428 if (IS_ERR(di_args)) 2429 return PTR_ERR(di_args); 2430 2431 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0) 2432 s_uuid = di_args->uuid; 2433 2434 mutex_lock(&fs_devices->device_list_mutex); 2435 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL); 2436 mutex_unlock(&fs_devices->device_list_mutex); 2437 2438 if (!dev) { 2439 ret = -ENODEV; 2440 goto out; 2441 } 2442 2443 di_args->devid = dev->devid; 2444 di_args->bytes_used = dev->bytes_used; 2445 di_args->total_bytes = dev->total_bytes; 2446 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 2447 if (dev->name) { 2448 struct rcu_string *name; 2449 2450 rcu_read_lock(); 2451 name = rcu_dereference(dev->name); 2452 strncpy(di_args->path, name->str, sizeof(di_args->path)); 2453 rcu_read_unlock(); 2454 di_args->path[sizeof(di_args->path) - 1] = 0; 2455 } else { 2456 di_args->path[0] = '\0'; 2457 } 2458 2459 out: 2460 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 2461 ret = -EFAULT; 2462 2463 kfree(di_args); 2464 return ret; 2465 } 2466 2467 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 2468 u64 off, u64 olen, u64 destoff) 2469 { 2470 struct inode *inode = file_inode(file); 2471 struct btrfs_root *root = BTRFS_I(inode)->root; 2472 struct fd src_file; 2473 struct inode *src; 2474 struct btrfs_trans_handle *trans; 2475 struct btrfs_path *path; 2476 struct extent_buffer *leaf; 2477 char *buf; 2478 struct btrfs_key key; 2479 u32 nritems; 2480 int slot; 2481 int ret; 2482 u64 len = olen; 2483 u64 bs = root->fs_info->sb->s_blocksize; 2484 2485 /* 2486 * TODO: 2487 * - split compressed inline extents. annoying: we need to 2488 * decompress into destination's address_space (the file offset 2489 * may change, so source mapping won't do), then recompress (or 2490 * otherwise reinsert) a subrange. 2491 * - allow ranges within the same file to be cloned (provided 2492 * they don't overlap)? 2493 */ 2494 2495 /* the destination must be opened for writing */ 2496 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) 2497 return -EINVAL; 2498 2499 if (btrfs_root_readonly(root)) 2500 return -EROFS; 2501 2502 ret = mnt_want_write_file(file); 2503 if (ret) 2504 return ret; 2505 2506 src_file = fdget(srcfd); 2507 if (!src_file.file) { 2508 ret = -EBADF; 2509 goto out_drop_write; 2510 } 2511 2512 ret = -EXDEV; 2513 if (src_file.file->f_path.mnt != file->f_path.mnt) 2514 goto out_fput; 2515 2516 src = file_inode(src_file.file); 2517 2518 ret = -EINVAL; 2519 if (src == inode) 2520 goto out_fput; 2521 2522 /* the src must be open for reading */ 2523 if (!(src_file.file->f_mode & FMODE_READ)) 2524 goto out_fput; 2525 2526 /* don't make the dst file partly checksummed */ 2527 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 2528 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) 2529 goto out_fput; 2530 2531 ret = -EISDIR; 2532 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 2533 goto out_fput; 2534 2535 ret = -EXDEV; 2536 if (src->i_sb != inode->i_sb) 2537 goto out_fput; 2538 2539 ret = -ENOMEM; 2540 buf = vmalloc(btrfs_level_size(root, 0)); 2541 if (!buf) 2542 goto out_fput; 2543 2544 path = btrfs_alloc_path(); 2545 if (!path) { 2546 vfree(buf); 2547 goto out_fput; 2548 } 2549 path->reada = 2; 2550 2551 if (inode < src) { 2552 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); 2553 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); 2554 } else { 2555 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); 2556 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); 2557 } 2558 2559 /* determine range to clone */ 2560 ret = -EINVAL; 2561 if (off + len > src->i_size || off + len < off) 2562 goto out_unlock; 2563 if (len == 0) 2564 olen = len = src->i_size - off; 2565 /* if we extend to eof, continue to block boundary */ 2566 if (off + len == src->i_size) 2567 len = ALIGN(src->i_size, bs) - off; 2568 2569 /* verify the end result is block aligned */ 2570 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || 2571 !IS_ALIGNED(destoff, bs)) 2572 goto out_unlock; 2573 2574 if (destoff > inode->i_size) { 2575 ret = btrfs_cont_expand(inode, inode->i_size, destoff); 2576 if (ret) 2577 goto out_unlock; 2578 } 2579 2580 /* truncate page cache pages from target inode range */ 2581 truncate_inode_pages_range(&inode->i_data, destoff, 2582 PAGE_CACHE_ALIGN(destoff + len) - 1); 2583 2584 /* do any pending delalloc/csum calc on src, one way or 2585 another, and lock file content */ 2586 while (1) { 2587 struct btrfs_ordered_extent *ordered; 2588 lock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); 2589 ordered = btrfs_lookup_first_ordered_extent(src, off + len - 1); 2590 if (!ordered && 2591 !test_range_bit(&BTRFS_I(src)->io_tree, off, off + len - 1, 2592 EXTENT_DELALLOC, 0, NULL)) 2593 break; 2594 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); 2595 if (ordered) 2596 btrfs_put_ordered_extent(ordered); 2597 btrfs_wait_ordered_range(src, off, len); 2598 } 2599 2600 /* clone data */ 2601 key.objectid = btrfs_ino(src); 2602 key.type = BTRFS_EXTENT_DATA_KEY; 2603 key.offset = 0; 2604 2605 while (1) { 2606 /* 2607 * note the key will change type as we walk through the 2608 * tree. 2609 */ 2610 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path, 2611 0, 0); 2612 if (ret < 0) 2613 goto out; 2614 2615 nritems = btrfs_header_nritems(path->nodes[0]); 2616 if (path->slots[0] >= nritems) { 2617 ret = btrfs_next_leaf(BTRFS_I(src)->root, path); 2618 if (ret < 0) 2619 goto out; 2620 if (ret > 0) 2621 break; 2622 nritems = btrfs_header_nritems(path->nodes[0]); 2623 } 2624 leaf = path->nodes[0]; 2625 slot = path->slots[0]; 2626 2627 btrfs_item_key_to_cpu(leaf, &key, slot); 2628 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || 2629 key.objectid != btrfs_ino(src)) 2630 break; 2631 2632 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { 2633 struct btrfs_file_extent_item *extent; 2634 int type; 2635 u32 size; 2636 struct btrfs_key new_key; 2637 u64 disko = 0, diskl = 0; 2638 u64 datao = 0, datal = 0; 2639 u8 comp; 2640 u64 endoff; 2641 2642 size = btrfs_item_size_nr(leaf, slot); 2643 read_extent_buffer(leaf, buf, 2644 btrfs_item_ptr_offset(leaf, slot), 2645 size); 2646 2647 extent = btrfs_item_ptr(leaf, slot, 2648 struct btrfs_file_extent_item); 2649 comp = btrfs_file_extent_compression(leaf, extent); 2650 type = btrfs_file_extent_type(leaf, extent); 2651 if (type == BTRFS_FILE_EXTENT_REG || 2652 type == BTRFS_FILE_EXTENT_PREALLOC) { 2653 disko = btrfs_file_extent_disk_bytenr(leaf, 2654 extent); 2655 diskl = btrfs_file_extent_disk_num_bytes(leaf, 2656 extent); 2657 datao = btrfs_file_extent_offset(leaf, extent); 2658 datal = btrfs_file_extent_num_bytes(leaf, 2659 extent); 2660 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2661 /* take upper bound, may be compressed */ 2662 datal = btrfs_file_extent_ram_bytes(leaf, 2663 extent); 2664 } 2665 btrfs_release_path(path); 2666 2667 if (key.offset + datal <= off || 2668 key.offset >= off + len - 1) 2669 goto next; 2670 2671 memcpy(&new_key, &key, sizeof(new_key)); 2672 new_key.objectid = btrfs_ino(inode); 2673 if (off <= key.offset) 2674 new_key.offset = key.offset + destoff - off; 2675 else 2676 new_key.offset = destoff; 2677 2678 /* 2679 * 1 - adjusting old extent (we may have to split it) 2680 * 1 - add new extent 2681 * 1 - inode update 2682 */ 2683 trans = btrfs_start_transaction(root, 3); 2684 if (IS_ERR(trans)) { 2685 ret = PTR_ERR(trans); 2686 goto out; 2687 } 2688 2689 if (type == BTRFS_FILE_EXTENT_REG || 2690 type == BTRFS_FILE_EXTENT_PREALLOC) { 2691 /* 2692 * a | --- range to clone ---| b 2693 * | ------------- extent ------------- | 2694 */ 2695 2696 /* substract range b */ 2697 if (key.offset + datal > off + len) 2698 datal = off + len - key.offset; 2699 2700 /* substract range a */ 2701 if (off > key.offset) { 2702 datao += off - key.offset; 2703 datal -= off - key.offset; 2704 } 2705 2706 ret = btrfs_drop_extents(trans, root, inode, 2707 new_key.offset, 2708 new_key.offset + datal, 2709 1); 2710 if (ret) { 2711 btrfs_abort_transaction(trans, root, 2712 ret); 2713 btrfs_end_transaction(trans, root); 2714 goto out; 2715 } 2716 2717 ret = btrfs_insert_empty_item(trans, root, path, 2718 &new_key, size); 2719 if (ret) { 2720 btrfs_abort_transaction(trans, root, 2721 ret); 2722 btrfs_end_transaction(trans, root); 2723 goto out; 2724 } 2725 2726 leaf = path->nodes[0]; 2727 slot = path->slots[0]; 2728 write_extent_buffer(leaf, buf, 2729 btrfs_item_ptr_offset(leaf, slot), 2730 size); 2731 2732 extent = btrfs_item_ptr(leaf, slot, 2733 struct btrfs_file_extent_item); 2734 2735 /* disko == 0 means it's a hole */ 2736 if (!disko) 2737 datao = 0; 2738 2739 btrfs_set_file_extent_offset(leaf, extent, 2740 datao); 2741 btrfs_set_file_extent_num_bytes(leaf, extent, 2742 datal); 2743 if (disko) { 2744 inode_add_bytes(inode, datal); 2745 ret = btrfs_inc_extent_ref(trans, root, 2746 disko, diskl, 0, 2747 root->root_key.objectid, 2748 btrfs_ino(inode), 2749 new_key.offset - datao, 2750 0); 2751 if (ret) { 2752 btrfs_abort_transaction(trans, 2753 root, 2754 ret); 2755 btrfs_end_transaction(trans, 2756 root); 2757 goto out; 2758 2759 } 2760 } 2761 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 2762 u64 skip = 0; 2763 u64 trim = 0; 2764 if (off > key.offset) { 2765 skip = off - key.offset; 2766 new_key.offset += skip; 2767 } 2768 2769 if (key.offset + datal > off + len) 2770 trim = key.offset + datal - (off + len); 2771 2772 if (comp && (skip || trim)) { 2773 ret = -EINVAL; 2774 btrfs_end_transaction(trans, root); 2775 goto out; 2776 } 2777 size -= skip + trim; 2778 datal -= skip + trim; 2779 2780 ret = btrfs_drop_extents(trans, root, inode, 2781 new_key.offset, 2782 new_key.offset + datal, 2783 1); 2784 if (ret) { 2785 btrfs_abort_transaction(trans, root, 2786 ret); 2787 btrfs_end_transaction(trans, root); 2788 goto out; 2789 } 2790 2791 ret = btrfs_insert_empty_item(trans, root, path, 2792 &new_key, size); 2793 if (ret) { 2794 btrfs_abort_transaction(trans, root, 2795 ret); 2796 btrfs_end_transaction(trans, root); 2797 goto out; 2798 } 2799 2800 if (skip) { 2801 u32 start = 2802 btrfs_file_extent_calc_inline_size(0); 2803 memmove(buf+start, buf+start+skip, 2804 datal); 2805 } 2806 2807 leaf = path->nodes[0]; 2808 slot = path->slots[0]; 2809 write_extent_buffer(leaf, buf, 2810 btrfs_item_ptr_offset(leaf, slot), 2811 size); 2812 inode_add_bytes(inode, datal); 2813 } 2814 2815 btrfs_mark_buffer_dirty(leaf); 2816 btrfs_release_path(path); 2817 2818 inode_inc_iversion(inode); 2819 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 2820 2821 /* 2822 * we round up to the block size at eof when 2823 * determining which extents to clone above, 2824 * but shouldn't round up the file size 2825 */ 2826 endoff = new_key.offset + datal; 2827 if (endoff > destoff+olen) 2828 endoff = destoff+olen; 2829 if (endoff > inode->i_size) 2830 btrfs_i_size_write(inode, endoff); 2831 2832 ret = btrfs_update_inode(trans, root, inode); 2833 if (ret) { 2834 btrfs_abort_transaction(trans, root, ret); 2835 btrfs_end_transaction(trans, root); 2836 goto out; 2837 } 2838 ret = btrfs_end_transaction(trans, root); 2839 } 2840 next: 2841 btrfs_release_path(path); 2842 key.offset++; 2843 } 2844 ret = 0; 2845 out: 2846 btrfs_release_path(path); 2847 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); 2848 out_unlock: 2849 mutex_unlock(&src->i_mutex); 2850 mutex_unlock(&inode->i_mutex); 2851 vfree(buf); 2852 btrfs_free_path(path); 2853 out_fput: 2854 fdput(src_file); 2855 out_drop_write: 2856 mnt_drop_write_file(file); 2857 return ret; 2858 } 2859 2860 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) 2861 { 2862 struct btrfs_ioctl_clone_range_args args; 2863 2864 if (copy_from_user(&args, argp, sizeof(args))) 2865 return -EFAULT; 2866 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, 2867 args.src_length, args.dest_offset); 2868 } 2869 2870 /* 2871 * there are many ways the trans_start and trans_end ioctls can lead 2872 * to deadlocks. They should only be used by applications that 2873 * basically own the machine, and have a very in depth understanding 2874 * of all the possible deadlocks and enospc problems. 2875 */ 2876 static long btrfs_ioctl_trans_start(struct file *file) 2877 { 2878 struct inode *inode = file_inode(file); 2879 struct btrfs_root *root = BTRFS_I(inode)->root; 2880 struct btrfs_trans_handle *trans; 2881 int ret; 2882 2883 ret = -EPERM; 2884 if (!capable(CAP_SYS_ADMIN)) 2885 goto out; 2886 2887 ret = -EINPROGRESS; 2888 if (file->private_data) 2889 goto out; 2890 2891 ret = -EROFS; 2892 if (btrfs_root_readonly(root)) 2893 goto out; 2894 2895 ret = mnt_want_write_file(file); 2896 if (ret) 2897 goto out; 2898 2899 atomic_inc(&root->fs_info->open_ioctl_trans); 2900 2901 ret = -ENOMEM; 2902 trans = btrfs_start_ioctl_transaction(root); 2903 if (IS_ERR(trans)) 2904 goto out_drop; 2905 2906 file->private_data = trans; 2907 return 0; 2908 2909 out_drop: 2910 atomic_dec(&root->fs_info->open_ioctl_trans); 2911 mnt_drop_write_file(file); 2912 out: 2913 return ret; 2914 } 2915 2916 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) 2917 { 2918 struct inode *inode = file_inode(file); 2919 struct btrfs_root *root = BTRFS_I(inode)->root; 2920 struct btrfs_root *new_root; 2921 struct btrfs_dir_item *di; 2922 struct btrfs_trans_handle *trans; 2923 struct btrfs_path *path; 2924 struct btrfs_key location; 2925 struct btrfs_disk_key disk_key; 2926 u64 objectid = 0; 2927 u64 dir_id; 2928 int ret; 2929 2930 if (!capable(CAP_SYS_ADMIN)) 2931 return -EPERM; 2932 2933 ret = mnt_want_write_file(file); 2934 if (ret) 2935 return ret; 2936 2937 if (copy_from_user(&objectid, argp, sizeof(objectid))) { 2938 ret = -EFAULT; 2939 goto out; 2940 } 2941 2942 if (!objectid) 2943 objectid = root->root_key.objectid; 2944 2945 location.objectid = objectid; 2946 location.type = BTRFS_ROOT_ITEM_KEY; 2947 location.offset = (u64)-1; 2948 2949 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); 2950 if (IS_ERR(new_root)) { 2951 ret = PTR_ERR(new_root); 2952 goto out; 2953 } 2954 2955 if (btrfs_root_refs(&new_root->root_item) == 0) { 2956 ret = -ENOENT; 2957 goto out; 2958 } 2959 2960 path = btrfs_alloc_path(); 2961 if (!path) { 2962 ret = -ENOMEM; 2963 goto out; 2964 } 2965 path->leave_spinning = 1; 2966 2967 trans = btrfs_start_transaction(root, 1); 2968 if (IS_ERR(trans)) { 2969 btrfs_free_path(path); 2970 ret = PTR_ERR(trans); 2971 goto out; 2972 } 2973 2974 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 2975 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, 2976 dir_id, "default", 7, 1); 2977 if (IS_ERR_OR_NULL(di)) { 2978 btrfs_free_path(path); 2979 btrfs_end_transaction(trans, root); 2980 printk(KERN_ERR "Umm, you don't have the default dir item, " 2981 "this isn't going to work\n"); 2982 ret = -ENOENT; 2983 goto out; 2984 } 2985 2986 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); 2987 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); 2988 btrfs_mark_buffer_dirty(path->nodes[0]); 2989 btrfs_free_path(path); 2990 2991 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL); 2992 btrfs_end_transaction(trans, root); 2993 out: 2994 mnt_drop_write_file(file); 2995 return ret; 2996 } 2997 2998 void btrfs_get_block_group_info(struct list_head *groups_list, 2999 struct btrfs_ioctl_space_info *space) 3000 { 3001 struct btrfs_block_group_cache *block_group; 3002 3003 space->total_bytes = 0; 3004 space->used_bytes = 0; 3005 space->flags = 0; 3006 list_for_each_entry(block_group, groups_list, list) { 3007 space->flags = block_group->flags; 3008 space->total_bytes += block_group->key.offset; 3009 space->used_bytes += 3010 btrfs_block_group_used(&block_group->item); 3011 } 3012 } 3013 3014 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) 3015 { 3016 struct btrfs_ioctl_space_args space_args; 3017 struct btrfs_ioctl_space_info space; 3018 struct btrfs_ioctl_space_info *dest; 3019 struct btrfs_ioctl_space_info *dest_orig; 3020 struct btrfs_ioctl_space_info __user *user_dest; 3021 struct btrfs_space_info *info; 3022 u64 types[] = {BTRFS_BLOCK_GROUP_DATA, 3023 BTRFS_BLOCK_GROUP_SYSTEM, 3024 BTRFS_BLOCK_GROUP_METADATA, 3025 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; 3026 int num_types = 4; 3027 int alloc_size; 3028 int ret = 0; 3029 u64 slot_count = 0; 3030 int i, c; 3031 3032 if (copy_from_user(&space_args, 3033 (struct btrfs_ioctl_space_args __user *)arg, 3034 sizeof(space_args))) 3035 return -EFAULT; 3036 3037 for (i = 0; i < num_types; i++) { 3038 struct btrfs_space_info *tmp; 3039 3040 info = NULL; 3041 rcu_read_lock(); 3042 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 3043 list) { 3044 if (tmp->flags == types[i]) { 3045 info = tmp; 3046 break; 3047 } 3048 } 3049 rcu_read_unlock(); 3050 3051 if (!info) 3052 continue; 3053 3054 down_read(&info->groups_sem); 3055 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 3056 if (!list_empty(&info->block_groups[c])) 3057 slot_count++; 3058 } 3059 up_read(&info->groups_sem); 3060 } 3061 3062 /* space_slots == 0 means they are asking for a count */ 3063 if (space_args.space_slots == 0) { 3064 space_args.total_spaces = slot_count; 3065 goto out; 3066 } 3067 3068 slot_count = min_t(u64, space_args.space_slots, slot_count); 3069 3070 alloc_size = sizeof(*dest) * slot_count; 3071 3072 /* we generally have at most 6 or so space infos, one for each raid 3073 * level. So, a whole page should be more than enough for everyone 3074 */ 3075 if (alloc_size > PAGE_CACHE_SIZE) 3076 return -ENOMEM; 3077 3078 space_args.total_spaces = 0; 3079 dest = kmalloc(alloc_size, GFP_NOFS); 3080 if (!dest) 3081 return -ENOMEM; 3082 dest_orig = dest; 3083 3084 /* now we have a buffer to copy into */ 3085 for (i = 0; i < num_types; i++) { 3086 struct btrfs_space_info *tmp; 3087 3088 if (!slot_count) 3089 break; 3090 3091 info = NULL; 3092 rcu_read_lock(); 3093 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 3094 list) { 3095 if (tmp->flags == types[i]) { 3096 info = tmp; 3097 break; 3098 } 3099 } 3100 rcu_read_unlock(); 3101 3102 if (!info) 3103 continue; 3104 down_read(&info->groups_sem); 3105 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 3106 if (!list_empty(&info->block_groups[c])) { 3107 btrfs_get_block_group_info( 3108 &info->block_groups[c], &space); 3109 memcpy(dest, &space, sizeof(space)); 3110 dest++; 3111 space_args.total_spaces++; 3112 slot_count--; 3113 } 3114 if (!slot_count) 3115 break; 3116 } 3117 up_read(&info->groups_sem); 3118 } 3119 3120 user_dest = (struct btrfs_ioctl_space_info __user *) 3121 (arg + sizeof(struct btrfs_ioctl_space_args)); 3122 3123 if (copy_to_user(user_dest, dest_orig, alloc_size)) 3124 ret = -EFAULT; 3125 3126 kfree(dest_orig); 3127 out: 3128 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) 3129 ret = -EFAULT; 3130 3131 return ret; 3132 } 3133 3134 /* 3135 * there are many ways the trans_start and trans_end ioctls can lead 3136 * to deadlocks. They should only be used by applications that 3137 * basically own the machine, and have a very in depth understanding 3138 * of all the possible deadlocks and enospc problems. 3139 */ 3140 long btrfs_ioctl_trans_end(struct file *file) 3141 { 3142 struct inode *inode = file_inode(file); 3143 struct btrfs_root *root = BTRFS_I(inode)->root; 3144 struct btrfs_trans_handle *trans; 3145 3146 trans = file->private_data; 3147 if (!trans) 3148 return -EINVAL; 3149 file->private_data = NULL; 3150 3151 btrfs_end_transaction(trans, root); 3152 3153 atomic_dec(&root->fs_info->open_ioctl_trans); 3154 3155 mnt_drop_write_file(file); 3156 return 0; 3157 } 3158 3159 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root, 3160 void __user *argp) 3161 { 3162 struct btrfs_trans_handle *trans; 3163 u64 transid; 3164 int ret; 3165 3166 trans = btrfs_attach_transaction_barrier(root); 3167 if (IS_ERR(trans)) { 3168 if (PTR_ERR(trans) != -ENOENT) 3169 return PTR_ERR(trans); 3170 3171 /* No running transaction, don't bother */ 3172 transid = root->fs_info->last_trans_committed; 3173 goto out; 3174 } 3175 transid = trans->transid; 3176 ret = btrfs_commit_transaction_async(trans, root, 0); 3177 if (ret) { 3178 btrfs_end_transaction(trans, root); 3179 return ret; 3180 } 3181 out: 3182 if (argp) 3183 if (copy_to_user(argp, &transid, sizeof(transid))) 3184 return -EFAULT; 3185 return 0; 3186 } 3187 3188 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root, 3189 void __user *argp) 3190 { 3191 u64 transid; 3192 3193 if (argp) { 3194 if (copy_from_user(&transid, argp, sizeof(transid))) 3195 return -EFAULT; 3196 } else { 3197 transid = 0; /* current trans */ 3198 } 3199 return btrfs_wait_for_commit(root, transid); 3200 } 3201 3202 static long btrfs_ioctl_scrub(struct file *file, void __user *arg) 3203 { 3204 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 3205 struct btrfs_ioctl_scrub_args *sa; 3206 int ret; 3207 3208 if (!capable(CAP_SYS_ADMIN)) 3209 return -EPERM; 3210 3211 sa = memdup_user(arg, sizeof(*sa)); 3212 if (IS_ERR(sa)) 3213 return PTR_ERR(sa); 3214 3215 if (!(sa->flags & BTRFS_SCRUB_READONLY)) { 3216 ret = mnt_want_write_file(file); 3217 if (ret) 3218 goto out; 3219 } 3220 3221 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end, 3222 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY, 3223 0); 3224 3225 if (copy_to_user(arg, sa, sizeof(*sa))) 3226 ret = -EFAULT; 3227 3228 if (!(sa->flags & BTRFS_SCRUB_READONLY)) 3229 mnt_drop_write_file(file); 3230 out: 3231 kfree(sa); 3232 return ret; 3233 } 3234 3235 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg) 3236 { 3237 if (!capable(CAP_SYS_ADMIN)) 3238 return -EPERM; 3239 3240 return btrfs_scrub_cancel(root->fs_info); 3241 } 3242 3243 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, 3244 void __user *arg) 3245 { 3246 struct btrfs_ioctl_scrub_args *sa; 3247 int ret; 3248 3249 if (!capable(CAP_SYS_ADMIN)) 3250 return -EPERM; 3251 3252 sa = memdup_user(arg, sizeof(*sa)); 3253 if (IS_ERR(sa)) 3254 return PTR_ERR(sa); 3255 3256 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress); 3257 3258 if (copy_to_user(arg, sa, sizeof(*sa))) 3259 ret = -EFAULT; 3260 3261 kfree(sa); 3262 return ret; 3263 } 3264 3265 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root, 3266 void __user *arg) 3267 { 3268 struct btrfs_ioctl_get_dev_stats *sa; 3269 int ret; 3270 3271 sa = memdup_user(arg, sizeof(*sa)); 3272 if (IS_ERR(sa)) 3273 return PTR_ERR(sa); 3274 3275 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) { 3276 kfree(sa); 3277 return -EPERM; 3278 } 3279 3280 ret = btrfs_get_dev_stats(root, sa); 3281 3282 if (copy_to_user(arg, sa, sizeof(*sa))) 3283 ret = -EFAULT; 3284 3285 kfree(sa); 3286 return ret; 3287 } 3288 3289 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg) 3290 { 3291 struct btrfs_ioctl_dev_replace_args *p; 3292 int ret; 3293 3294 if (!capable(CAP_SYS_ADMIN)) 3295 return -EPERM; 3296 3297 p = memdup_user(arg, sizeof(*p)); 3298 if (IS_ERR(p)) 3299 return PTR_ERR(p); 3300 3301 switch (p->cmd) { 3302 case BTRFS_IOCTL_DEV_REPLACE_CMD_START: 3303 if (atomic_xchg( 3304 &root->fs_info->mutually_exclusive_operation_running, 3305 1)) { 3306 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); 3307 ret = -EINPROGRESS; 3308 } else { 3309 ret = btrfs_dev_replace_start(root, p); 3310 atomic_set( 3311 &root->fs_info->mutually_exclusive_operation_running, 3312 0); 3313 } 3314 break; 3315 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS: 3316 btrfs_dev_replace_status(root->fs_info, p); 3317 ret = 0; 3318 break; 3319 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL: 3320 ret = btrfs_dev_replace_cancel(root->fs_info, p); 3321 break; 3322 default: 3323 ret = -EINVAL; 3324 break; 3325 } 3326 3327 if (copy_to_user(arg, p, sizeof(*p))) 3328 ret = -EFAULT; 3329 3330 kfree(p); 3331 return ret; 3332 } 3333 3334 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) 3335 { 3336 int ret = 0; 3337 int i; 3338 u64 rel_ptr; 3339 int size; 3340 struct btrfs_ioctl_ino_path_args *ipa = NULL; 3341 struct inode_fs_paths *ipath = NULL; 3342 struct btrfs_path *path; 3343 3344 if (!capable(CAP_DAC_READ_SEARCH)) 3345 return -EPERM; 3346 3347 path = btrfs_alloc_path(); 3348 if (!path) { 3349 ret = -ENOMEM; 3350 goto out; 3351 } 3352 3353 ipa = memdup_user(arg, sizeof(*ipa)); 3354 if (IS_ERR(ipa)) { 3355 ret = PTR_ERR(ipa); 3356 ipa = NULL; 3357 goto out; 3358 } 3359 3360 size = min_t(u32, ipa->size, 4096); 3361 ipath = init_ipath(size, root, path); 3362 if (IS_ERR(ipath)) { 3363 ret = PTR_ERR(ipath); 3364 ipath = NULL; 3365 goto out; 3366 } 3367 3368 ret = paths_from_inode(ipa->inum, ipath); 3369 if (ret < 0) 3370 goto out; 3371 3372 for (i = 0; i < ipath->fspath->elem_cnt; ++i) { 3373 rel_ptr = ipath->fspath->val[i] - 3374 (u64)(unsigned long)ipath->fspath->val; 3375 ipath->fspath->val[i] = rel_ptr; 3376 } 3377 3378 ret = copy_to_user((void *)(unsigned long)ipa->fspath, 3379 (void *)(unsigned long)ipath->fspath, size); 3380 if (ret) { 3381 ret = -EFAULT; 3382 goto out; 3383 } 3384 3385 out: 3386 btrfs_free_path(path); 3387 free_ipath(ipath); 3388 kfree(ipa); 3389 3390 return ret; 3391 } 3392 3393 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) 3394 { 3395 struct btrfs_data_container *inodes = ctx; 3396 const size_t c = 3 * sizeof(u64); 3397 3398 if (inodes->bytes_left >= c) { 3399 inodes->bytes_left -= c; 3400 inodes->val[inodes->elem_cnt] = inum; 3401 inodes->val[inodes->elem_cnt + 1] = offset; 3402 inodes->val[inodes->elem_cnt + 2] = root; 3403 inodes->elem_cnt += 3; 3404 } else { 3405 inodes->bytes_missing += c - inodes->bytes_left; 3406 inodes->bytes_left = 0; 3407 inodes->elem_missed += 3; 3408 } 3409 3410 return 0; 3411 } 3412 3413 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 3414 void __user *arg) 3415 { 3416 int ret = 0; 3417 int size; 3418 struct btrfs_ioctl_logical_ino_args *loi; 3419 struct btrfs_data_container *inodes = NULL; 3420 struct btrfs_path *path = NULL; 3421 3422 if (!capable(CAP_SYS_ADMIN)) 3423 return -EPERM; 3424 3425 loi = memdup_user(arg, sizeof(*loi)); 3426 if (IS_ERR(loi)) { 3427 ret = PTR_ERR(loi); 3428 loi = NULL; 3429 goto out; 3430 } 3431 3432 path = btrfs_alloc_path(); 3433 if (!path) { 3434 ret = -ENOMEM; 3435 goto out; 3436 } 3437 3438 size = min_t(u32, loi->size, 64 * 1024); 3439 inodes = init_data_container(size); 3440 if (IS_ERR(inodes)) { 3441 ret = PTR_ERR(inodes); 3442 inodes = NULL; 3443 goto out; 3444 } 3445 3446 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path, 3447 build_ino_list, inodes); 3448 if (ret == -EINVAL) 3449 ret = -ENOENT; 3450 if (ret < 0) 3451 goto out; 3452 3453 ret = copy_to_user((void *)(unsigned long)loi->inodes, 3454 (void *)(unsigned long)inodes, size); 3455 if (ret) 3456 ret = -EFAULT; 3457 3458 out: 3459 btrfs_free_path(path); 3460 vfree(inodes); 3461 kfree(loi); 3462 3463 return ret; 3464 } 3465 3466 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3467 struct btrfs_ioctl_balance_args *bargs) 3468 { 3469 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3470 3471 bargs->flags = bctl->flags; 3472 3473 if (atomic_read(&fs_info->balance_running)) 3474 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 3475 if (atomic_read(&fs_info->balance_pause_req)) 3476 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 3477 if (atomic_read(&fs_info->balance_cancel_req)) 3478 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 3479 3480 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 3481 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 3482 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 3483 3484 if (lock) { 3485 spin_lock(&fs_info->balance_lock); 3486 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3487 spin_unlock(&fs_info->balance_lock); 3488 } else { 3489 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3490 } 3491 } 3492 3493 static long btrfs_ioctl_balance(struct file *file, void __user *arg) 3494 { 3495 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 3496 struct btrfs_fs_info *fs_info = root->fs_info; 3497 struct btrfs_ioctl_balance_args *bargs; 3498 struct btrfs_balance_control *bctl; 3499 bool need_unlock; /* for mut. excl. ops lock */ 3500 int ret; 3501 3502 if (!capable(CAP_SYS_ADMIN)) 3503 return -EPERM; 3504 3505 ret = mnt_want_write_file(file); 3506 if (ret) 3507 return ret; 3508 3509 again: 3510 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) { 3511 mutex_lock(&fs_info->volume_mutex); 3512 mutex_lock(&fs_info->balance_mutex); 3513 need_unlock = true; 3514 goto locked; 3515 } 3516 3517 /* 3518 * mut. excl. ops lock is locked. Three possibilites: 3519 * (1) some other op is running 3520 * (2) balance is running 3521 * (3) balance is paused -- special case (think resume) 3522 */ 3523 mutex_lock(&fs_info->balance_mutex); 3524 if (fs_info->balance_ctl) { 3525 /* this is either (2) or (3) */ 3526 if (!atomic_read(&fs_info->balance_running)) { 3527 mutex_unlock(&fs_info->balance_mutex); 3528 if (!mutex_trylock(&fs_info->volume_mutex)) 3529 goto again; 3530 mutex_lock(&fs_info->balance_mutex); 3531 3532 if (fs_info->balance_ctl && 3533 !atomic_read(&fs_info->balance_running)) { 3534 /* this is (3) */ 3535 need_unlock = false; 3536 goto locked; 3537 } 3538 3539 mutex_unlock(&fs_info->balance_mutex); 3540 mutex_unlock(&fs_info->volume_mutex); 3541 goto again; 3542 } else { 3543 /* this is (2) */ 3544 mutex_unlock(&fs_info->balance_mutex); 3545 ret = -EINPROGRESS; 3546 goto out; 3547 } 3548 } else { 3549 /* this is (1) */ 3550 mutex_unlock(&fs_info->balance_mutex); 3551 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); 3552 ret = -EINVAL; 3553 goto out; 3554 } 3555 3556 locked: 3557 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running)); 3558 3559 if (arg) { 3560 bargs = memdup_user(arg, sizeof(*bargs)); 3561 if (IS_ERR(bargs)) { 3562 ret = PTR_ERR(bargs); 3563 goto out_unlock; 3564 } 3565 3566 if (bargs->flags & BTRFS_BALANCE_RESUME) { 3567 if (!fs_info->balance_ctl) { 3568 ret = -ENOTCONN; 3569 goto out_bargs; 3570 } 3571 3572 bctl = fs_info->balance_ctl; 3573 spin_lock(&fs_info->balance_lock); 3574 bctl->flags |= BTRFS_BALANCE_RESUME; 3575 spin_unlock(&fs_info->balance_lock); 3576 3577 goto do_balance; 3578 } 3579 } else { 3580 bargs = NULL; 3581 } 3582 3583 if (fs_info->balance_ctl) { 3584 ret = -EINPROGRESS; 3585 goto out_bargs; 3586 } 3587 3588 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3589 if (!bctl) { 3590 ret = -ENOMEM; 3591 goto out_bargs; 3592 } 3593 3594 bctl->fs_info = fs_info; 3595 if (arg) { 3596 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 3597 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 3598 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 3599 3600 bctl->flags = bargs->flags; 3601 } else { 3602 /* balance everything - no filters */ 3603 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 3604 } 3605 3606 do_balance: 3607 /* 3608 * Ownership of bctl and mutually_exclusive_operation_running 3609 * goes to to btrfs_balance. bctl is freed in __cancel_balance, 3610 * or, if restriper was paused all the way until unmount, in 3611 * free_fs_info. mutually_exclusive_operation_running is 3612 * cleared in __cancel_balance. 3613 */ 3614 need_unlock = false; 3615 3616 ret = btrfs_balance(bctl, bargs); 3617 3618 if (arg) { 3619 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3620 ret = -EFAULT; 3621 } 3622 3623 out_bargs: 3624 kfree(bargs); 3625 out_unlock: 3626 mutex_unlock(&fs_info->balance_mutex); 3627 mutex_unlock(&fs_info->volume_mutex); 3628 if (need_unlock) 3629 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3630 out: 3631 mnt_drop_write_file(file); 3632 return ret; 3633 } 3634 3635 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) 3636 { 3637 if (!capable(CAP_SYS_ADMIN)) 3638 return -EPERM; 3639 3640 switch (cmd) { 3641 case BTRFS_BALANCE_CTL_PAUSE: 3642 return btrfs_pause_balance(root->fs_info); 3643 case BTRFS_BALANCE_CTL_CANCEL: 3644 return btrfs_cancel_balance(root->fs_info); 3645 } 3646 3647 return -EINVAL; 3648 } 3649 3650 static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 3651 void __user *arg) 3652 { 3653 struct btrfs_fs_info *fs_info = root->fs_info; 3654 struct btrfs_ioctl_balance_args *bargs; 3655 int ret = 0; 3656 3657 if (!capable(CAP_SYS_ADMIN)) 3658 return -EPERM; 3659 3660 mutex_lock(&fs_info->balance_mutex); 3661 if (!fs_info->balance_ctl) { 3662 ret = -ENOTCONN; 3663 goto out; 3664 } 3665 3666 bargs = kzalloc(sizeof(*bargs), GFP_NOFS); 3667 if (!bargs) { 3668 ret = -ENOMEM; 3669 goto out; 3670 } 3671 3672 update_ioctl_balance_args(fs_info, 1, bargs); 3673 3674 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3675 ret = -EFAULT; 3676 3677 kfree(bargs); 3678 out: 3679 mutex_unlock(&fs_info->balance_mutex); 3680 return ret; 3681 } 3682 3683 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg) 3684 { 3685 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 3686 struct btrfs_ioctl_quota_ctl_args *sa; 3687 struct btrfs_trans_handle *trans = NULL; 3688 int ret; 3689 int err; 3690 3691 if (!capable(CAP_SYS_ADMIN)) 3692 return -EPERM; 3693 3694 ret = mnt_want_write_file(file); 3695 if (ret) 3696 return ret; 3697 3698 sa = memdup_user(arg, sizeof(*sa)); 3699 if (IS_ERR(sa)) { 3700 ret = PTR_ERR(sa); 3701 goto drop_write; 3702 } 3703 3704 if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) { 3705 trans = btrfs_start_transaction(root, 2); 3706 if (IS_ERR(trans)) { 3707 ret = PTR_ERR(trans); 3708 goto out; 3709 } 3710 } 3711 3712 switch (sa->cmd) { 3713 case BTRFS_QUOTA_CTL_ENABLE: 3714 ret = btrfs_quota_enable(trans, root->fs_info); 3715 break; 3716 case BTRFS_QUOTA_CTL_DISABLE: 3717 ret = btrfs_quota_disable(trans, root->fs_info); 3718 break; 3719 case BTRFS_QUOTA_CTL_RESCAN: 3720 ret = btrfs_quota_rescan(root->fs_info); 3721 break; 3722 default: 3723 ret = -EINVAL; 3724 break; 3725 } 3726 3727 if (copy_to_user(arg, sa, sizeof(*sa))) 3728 ret = -EFAULT; 3729 3730 if (trans) { 3731 err = btrfs_commit_transaction(trans, root); 3732 if (err && !ret) 3733 ret = err; 3734 } 3735 out: 3736 kfree(sa); 3737 drop_write: 3738 mnt_drop_write_file(file); 3739 return ret; 3740 } 3741 3742 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg) 3743 { 3744 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 3745 struct btrfs_ioctl_qgroup_assign_args *sa; 3746 struct btrfs_trans_handle *trans; 3747 int ret; 3748 int err; 3749 3750 if (!capable(CAP_SYS_ADMIN)) 3751 return -EPERM; 3752 3753 ret = mnt_want_write_file(file); 3754 if (ret) 3755 return ret; 3756 3757 sa = memdup_user(arg, sizeof(*sa)); 3758 if (IS_ERR(sa)) { 3759 ret = PTR_ERR(sa); 3760 goto drop_write; 3761 } 3762 3763 trans = btrfs_join_transaction(root); 3764 if (IS_ERR(trans)) { 3765 ret = PTR_ERR(trans); 3766 goto out; 3767 } 3768 3769 /* FIXME: check if the IDs really exist */ 3770 if (sa->assign) { 3771 ret = btrfs_add_qgroup_relation(trans, root->fs_info, 3772 sa->src, sa->dst); 3773 } else { 3774 ret = btrfs_del_qgroup_relation(trans, root->fs_info, 3775 sa->src, sa->dst); 3776 } 3777 3778 err = btrfs_end_transaction(trans, root); 3779 if (err && !ret) 3780 ret = err; 3781 3782 out: 3783 kfree(sa); 3784 drop_write: 3785 mnt_drop_write_file(file); 3786 return ret; 3787 } 3788 3789 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg) 3790 { 3791 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 3792 struct btrfs_ioctl_qgroup_create_args *sa; 3793 struct btrfs_trans_handle *trans; 3794 int ret; 3795 int err; 3796 3797 if (!capable(CAP_SYS_ADMIN)) 3798 return -EPERM; 3799 3800 ret = mnt_want_write_file(file); 3801 if (ret) 3802 return ret; 3803 3804 sa = memdup_user(arg, sizeof(*sa)); 3805 if (IS_ERR(sa)) { 3806 ret = PTR_ERR(sa); 3807 goto drop_write; 3808 } 3809 3810 if (!sa->qgroupid) { 3811 ret = -EINVAL; 3812 goto out; 3813 } 3814 3815 trans = btrfs_join_transaction(root); 3816 if (IS_ERR(trans)) { 3817 ret = PTR_ERR(trans); 3818 goto out; 3819 } 3820 3821 /* FIXME: check if the IDs really exist */ 3822 if (sa->create) { 3823 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid, 3824 NULL); 3825 } else { 3826 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid); 3827 } 3828 3829 err = btrfs_end_transaction(trans, root); 3830 if (err && !ret) 3831 ret = err; 3832 3833 out: 3834 kfree(sa); 3835 drop_write: 3836 mnt_drop_write_file(file); 3837 return ret; 3838 } 3839 3840 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg) 3841 { 3842 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 3843 struct btrfs_ioctl_qgroup_limit_args *sa; 3844 struct btrfs_trans_handle *trans; 3845 int ret; 3846 int err; 3847 u64 qgroupid; 3848 3849 if (!capable(CAP_SYS_ADMIN)) 3850 return -EPERM; 3851 3852 ret = mnt_want_write_file(file); 3853 if (ret) 3854 return ret; 3855 3856 sa = memdup_user(arg, sizeof(*sa)); 3857 if (IS_ERR(sa)) { 3858 ret = PTR_ERR(sa); 3859 goto drop_write; 3860 } 3861 3862 trans = btrfs_join_transaction(root); 3863 if (IS_ERR(trans)) { 3864 ret = PTR_ERR(trans); 3865 goto out; 3866 } 3867 3868 qgroupid = sa->qgroupid; 3869 if (!qgroupid) { 3870 /* take the current subvol as qgroup */ 3871 qgroupid = root->root_key.objectid; 3872 } 3873 3874 /* FIXME: check if the IDs really exist */ 3875 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim); 3876 3877 err = btrfs_end_transaction(trans, root); 3878 if (err && !ret) 3879 ret = err; 3880 3881 out: 3882 kfree(sa); 3883 drop_write: 3884 mnt_drop_write_file(file); 3885 return ret; 3886 } 3887 3888 static long btrfs_ioctl_set_received_subvol(struct file *file, 3889 void __user *arg) 3890 { 3891 struct btrfs_ioctl_received_subvol_args *sa = NULL; 3892 struct inode *inode = file_inode(file); 3893 struct btrfs_root *root = BTRFS_I(inode)->root; 3894 struct btrfs_root_item *root_item = &root->root_item; 3895 struct btrfs_trans_handle *trans; 3896 struct timespec ct = CURRENT_TIME; 3897 int ret = 0; 3898 3899 ret = mnt_want_write_file(file); 3900 if (ret < 0) 3901 return ret; 3902 3903 down_write(&root->fs_info->subvol_sem); 3904 3905 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 3906 ret = -EINVAL; 3907 goto out; 3908 } 3909 3910 if (btrfs_root_readonly(root)) { 3911 ret = -EROFS; 3912 goto out; 3913 } 3914 3915 if (!inode_owner_or_capable(inode)) { 3916 ret = -EACCES; 3917 goto out; 3918 } 3919 3920 sa = memdup_user(arg, sizeof(*sa)); 3921 if (IS_ERR(sa)) { 3922 ret = PTR_ERR(sa); 3923 sa = NULL; 3924 goto out; 3925 } 3926 3927 trans = btrfs_start_transaction(root, 1); 3928 if (IS_ERR(trans)) { 3929 ret = PTR_ERR(trans); 3930 trans = NULL; 3931 goto out; 3932 } 3933 3934 sa->rtransid = trans->transid; 3935 sa->rtime.sec = ct.tv_sec; 3936 sa->rtime.nsec = ct.tv_nsec; 3937 3938 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); 3939 btrfs_set_root_stransid(root_item, sa->stransid); 3940 btrfs_set_root_rtransid(root_item, sa->rtransid); 3941 root_item->stime.sec = cpu_to_le64(sa->stime.sec); 3942 root_item->stime.nsec = cpu_to_le32(sa->stime.nsec); 3943 root_item->rtime.sec = cpu_to_le64(sa->rtime.sec); 3944 root_item->rtime.nsec = cpu_to_le32(sa->rtime.nsec); 3945 3946 ret = btrfs_update_root(trans, root->fs_info->tree_root, 3947 &root->root_key, &root->root_item); 3948 if (ret < 0) { 3949 btrfs_end_transaction(trans, root); 3950 trans = NULL; 3951 goto out; 3952 } else { 3953 ret = btrfs_commit_transaction(trans, root); 3954 if (ret < 0) 3955 goto out; 3956 } 3957 3958 ret = copy_to_user(arg, sa, sizeof(*sa)); 3959 if (ret) 3960 ret = -EFAULT; 3961 3962 out: 3963 kfree(sa); 3964 up_write(&root->fs_info->subvol_sem); 3965 mnt_drop_write_file(file); 3966 return ret; 3967 } 3968 3969 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) 3970 { 3971 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 3972 const char *label = root->fs_info->super_copy->label; 3973 size_t len = strnlen(label, BTRFS_LABEL_SIZE); 3974 int ret; 3975 3976 if (len == BTRFS_LABEL_SIZE) { 3977 pr_warn("btrfs: label is too long, return the first %zu bytes\n", 3978 --len); 3979 } 3980 3981 mutex_lock(&root->fs_info->volume_mutex); 3982 ret = copy_to_user(arg, label, len); 3983 mutex_unlock(&root->fs_info->volume_mutex); 3984 3985 return ret ? -EFAULT : 0; 3986 } 3987 3988 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) 3989 { 3990 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 3991 struct btrfs_super_block *super_block = root->fs_info->super_copy; 3992 struct btrfs_trans_handle *trans; 3993 char label[BTRFS_LABEL_SIZE]; 3994 int ret; 3995 3996 if (!capable(CAP_SYS_ADMIN)) 3997 return -EPERM; 3998 3999 if (copy_from_user(label, arg, sizeof(label))) 4000 return -EFAULT; 4001 4002 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) { 4003 pr_err("btrfs: unable to set label with more than %d bytes\n", 4004 BTRFS_LABEL_SIZE - 1); 4005 return -EINVAL; 4006 } 4007 4008 ret = mnt_want_write_file(file); 4009 if (ret) 4010 return ret; 4011 4012 mutex_lock(&root->fs_info->volume_mutex); 4013 trans = btrfs_start_transaction(root, 0); 4014 if (IS_ERR(trans)) { 4015 ret = PTR_ERR(trans); 4016 goto out_unlock; 4017 } 4018 4019 strcpy(super_block->label, label); 4020 ret = btrfs_end_transaction(trans, root); 4021 4022 out_unlock: 4023 mutex_unlock(&root->fs_info->volume_mutex); 4024 mnt_drop_write_file(file); 4025 return ret; 4026 } 4027 4028 long btrfs_ioctl(struct file *file, unsigned int 4029 cmd, unsigned long arg) 4030 { 4031 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4032 void __user *argp = (void __user *)arg; 4033 4034 switch (cmd) { 4035 case FS_IOC_GETFLAGS: 4036 return btrfs_ioctl_getflags(file, argp); 4037 case FS_IOC_SETFLAGS: 4038 return btrfs_ioctl_setflags(file, argp); 4039 case FS_IOC_GETVERSION: 4040 return btrfs_ioctl_getversion(file, argp); 4041 case FITRIM: 4042 return btrfs_ioctl_fitrim(file, argp); 4043 case BTRFS_IOC_SNAP_CREATE: 4044 return btrfs_ioctl_snap_create(file, argp, 0); 4045 case BTRFS_IOC_SNAP_CREATE_V2: 4046 return btrfs_ioctl_snap_create_v2(file, argp, 0); 4047 case BTRFS_IOC_SUBVOL_CREATE: 4048 return btrfs_ioctl_snap_create(file, argp, 1); 4049 case BTRFS_IOC_SUBVOL_CREATE_V2: 4050 return btrfs_ioctl_snap_create_v2(file, argp, 1); 4051 case BTRFS_IOC_SNAP_DESTROY: 4052 return btrfs_ioctl_snap_destroy(file, argp); 4053 case BTRFS_IOC_SUBVOL_GETFLAGS: 4054 return btrfs_ioctl_subvol_getflags(file, argp); 4055 case BTRFS_IOC_SUBVOL_SETFLAGS: 4056 return btrfs_ioctl_subvol_setflags(file, argp); 4057 case BTRFS_IOC_DEFAULT_SUBVOL: 4058 return btrfs_ioctl_default_subvol(file, argp); 4059 case BTRFS_IOC_DEFRAG: 4060 return btrfs_ioctl_defrag(file, NULL); 4061 case BTRFS_IOC_DEFRAG_RANGE: 4062 return btrfs_ioctl_defrag(file, argp); 4063 case BTRFS_IOC_RESIZE: 4064 return btrfs_ioctl_resize(file, argp); 4065 case BTRFS_IOC_ADD_DEV: 4066 return btrfs_ioctl_add_dev(root, argp); 4067 case BTRFS_IOC_RM_DEV: 4068 return btrfs_ioctl_rm_dev(file, argp); 4069 case BTRFS_IOC_FS_INFO: 4070 return btrfs_ioctl_fs_info(root, argp); 4071 case BTRFS_IOC_DEV_INFO: 4072 return btrfs_ioctl_dev_info(root, argp); 4073 case BTRFS_IOC_BALANCE: 4074 return btrfs_ioctl_balance(file, NULL); 4075 case BTRFS_IOC_CLONE: 4076 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 4077 case BTRFS_IOC_CLONE_RANGE: 4078 return btrfs_ioctl_clone_range(file, argp); 4079 case BTRFS_IOC_TRANS_START: 4080 return btrfs_ioctl_trans_start(file); 4081 case BTRFS_IOC_TRANS_END: 4082 return btrfs_ioctl_trans_end(file); 4083 case BTRFS_IOC_TREE_SEARCH: 4084 return btrfs_ioctl_tree_search(file, argp); 4085 case BTRFS_IOC_INO_LOOKUP: 4086 return btrfs_ioctl_ino_lookup(file, argp); 4087 case BTRFS_IOC_INO_PATHS: 4088 return btrfs_ioctl_ino_to_path(root, argp); 4089 case BTRFS_IOC_LOGICAL_INO: 4090 return btrfs_ioctl_logical_to_ino(root, argp); 4091 case BTRFS_IOC_SPACE_INFO: 4092 return btrfs_ioctl_space_info(root, argp); 4093 case BTRFS_IOC_SYNC: 4094 btrfs_sync_fs(file->f_dentry->d_sb, 1); 4095 return 0; 4096 case BTRFS_IOC_START_SYNC: 4097 return btrfs_ioctl_start_sync(root, argp); 4098 case BTRFS_IOC_WAIT_SYNC: 4099 return btrfs_ioctl_wait_sync(root, argp); 4100 case BTRFS_IOC_SCRUB: 4101 return btrfs_ioctl_scrub(file, argp); 4102 case BTRFS_IOC_SCRUB_CANCEL: 4103 return btrfs_ioctl_scrub_cancel(root, argp); 4104 case BTRFS_IOC_SCRUB_PROGRESS: 4105 return btrfs_ioctl_scrub_progress(root, argp); 4106 case BTRFS_IOC_BALANCE_V2: 4107 return btrfs_ioctl_balance(file, argp); 4108 case BTRFS_IOC_BALANCE_CTL: 4109 return btrfs_ioctl_balance_ctl(root, arg); 4110 case BTRFS_IOC_BALANCE_PROGRESS: 4111 return btrfs_ioctl_balance_progress(root, argp); 4112 case BTRFS_IOC_SET_RECEIVED_SUBVOL: 4113 return btrfs_ioctl_set_received_subvol(file, argp); 4114 case BTRFS_IOC_SEND: 4115 return btrfs_ioctl_send(file, argp); 4116 case BTRFS_IOC_GET_DEV_STATS: 4117 return btrfs_ioctl_get_dev_stats(root, argp); 4118 case BTRFS_IOC_QUOTA_CTL: 4119 return btrfs_ioctl_quota_ctl(file, argp); 4120 case BTRFS_IOC_QGROUP_ASSIGN: 4121 return btrfs_ioctl_qgroup_assign(file, argp); 4122 case BTRFS_IOC_QGROUP_CREATE: 4123 return btrfs_ioctl_qgroup_create(file, argp); 4124 case BTRFS_IOC_QGROUP_LIMIT: 4125 return btrfs_ioctl_qgroup_limit(file, argp); 4126 case BTRFS_IOC_DEV_REPLACE: 4127 return btrfs_ioctl_dev_replace(root, argp); 4128 case BTRFS_IOC_GET_FSLABEL: 4129 return btrfs_ioctl_get_fslabel(file, argp); 4130 case BTRFS_IOC_SET_FSLABEL: 4131 return btrfs_ioctl_set_fslabel(file, argp); 4132 } 4133 4134 return -ENOTTY; 4135 } 4136