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