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