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 BTRFS_BLOCK_RSV_TEMP); 521 pending_snapshot->dentry = dentry; 522 pending_snapshot->root = root; 523 pending_snapshot->readonly = readonly; 524 if (inherit) { 525 pending_snapshot->inherit = *inherit; 526 *inherit = NULL; /* take responsibility to free it */ 527 } 528 529 trans = btrfs_start_transaction(root->fs_info->extent_root, 6); 530 if (IS_ERR(trans)) { 531 ret = PTR_ERR(trans); 532 goto fail; 533 } 534 535 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot); 536 BUG_ON(ret); 537 538 spin_lock(&root->fs_info->trans_lock); 539 list_add(&pending_snapshot->list, 540 &trans->transaction->pending_snapshots); 541 spin_unlock(&root->fs_info->trans_lock); 542 if (async_transid) { 543 *async_transid = trans->transid; 544 ret = btrfs_commit_transaction_async(trans, 545 root->fs_info->extent_root, 1); 546 } else { 547 ret = btrfs_commit_transaction(trans, 548 root->fs_info->extent_root); 549 } 550 BUG_ON(ret); 551 552 ret = pending_snapshot->error; 553 if (ret) 554 goto fail; 555 556 ret = btrfs_orphan_cleanup(pending_snapshot->snap); 557 if (ret) 558 goto fail; 559 560 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry); 561 if (IS_ERR(inode)) { 562 ret = PTR_ERR(inode); 563 goto fail; 564 } 565 BUG_ON(!inode); 566 d_instantiate(dentry, inode); 567 ret = 0; 568 fail: 569 kfree(pending_snapshot); 570 return ret; 571 } 572 573 /* copy of check_sticky in fs/namei.c() 574 * It's inline, so penalty for filesystems that don't use sticky bit is 575 * minimal. 576 */ 577 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode) 578 { 579 uid_t fsuid = current_fsuid(); 580 581 if (!(dir->i_mode & S_ISVTX)) 582 return 0; 583 if (inode->i_uid == fsuid) 584 return 0; 585 if (dir->i_uid == fsuid) 586 return 0; 587 return !capable(CAP_FOWNER); 588 } 589 590 /* copy of may_delete in fs/namei.c() 591 * Check whether we can remove a link victim from directory dir, check 592 * whether the type of victim is right. 593 * 1. We can't do it if dir is read-only (done in permission()) 594 * 2. We should have write and exec permissions on dir 595 * 3. We can't remove anything from append-only dir 596 * 4. We can't do anything with immutable dir (done in permission()) 597 * 5. If the sticky bit on dir is set we should either 598 * a. be owner of dir, or 599 * b. be owner of victim, or 600 * c. have CAP_FOWNER capability 601 * 6. If the victim is append-only or immutable we can't do antyhing with 602 * links pointing to it. 603 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. 604 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. 605 * 9. We can't remove a root or mountpoint. 606 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by 607 * nfs_async_unlink(). 608 */ 609 610 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir) 611 { 612 int error; 613 614 if (!victim->d_inode) 615 return -ENOENT; 616 617 BUG_ON(victim->d_parent->d_inode != dir); 618 audit_inode_child(victim, dir); 619 620 error = inode_permission(dir, MAY_WRITE | MAY_EXEC); 621 if (error) 622 return error; 623 if (IS_APPEND(dir)) 624 return -EPERM; 625 if (btrfs_check_sticky(dir, victim->d_inode)|| 626 IS_APPEND(victim->d_inode)|| 627 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) 628 return -EPERM; 629 if (isdir) { 630 if (!S_ISDIR(victim->d_inode->i_mode)) 631 return -ENOTDIR; 632 if (IS_ROOT(victim)) 633 return -EBUSY; 634 } else if (S_ISDIR(victim->d_inode->i_mode)) 635 return -EISDIR; 636 if (IS_DEADDIR(dir)) 637 return -ENOENT; 638 if (victim->d_flags & DCACHE_NFSFS_RENAMED) 639 return -EBUSY; 640 return 0; 641 } 642 643 /* copy of may_create in fs/namei.c() */ 644 static inline int btrfs_may_create(struct inode *dir, struct dentry *child) 645 { 646 if (child->d_inode) 647 return -EEXIST; 648 if (IS_DEADDIR(dir)) 649 return -ENOENT; 650 return inode_permission(dir, MAY_WRITE | MAY_EXEC); 651 } 652 653 /* 654 * Create a new subvolume below @parent. This is largely modeled after 655 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup 656 * inside this filesystem so it's quite a bit simpler. 657 */ 658 static noinline int btrfs_mksubvol(struct path *parent, 659 char *name, int namelen, 660 struct btrfs_root *snap_src, 661 u64 *async_transid, bool readonly, 662 struct btrfs_qgroup_inherit **inherit) 663 { 664 struct inode *dir = parent->dentry->d_inode; 665 struct dentry *dentry; 666 int error; 667 668 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 669 670 dentry = lookup_one_len(name, parent->dentry, namelen); 671 error = PTR_ERR(dentry); 672 if (IS_ERR(dentry)) 673 goto out_unlock; 674 675 error = -EEXIST; 676 if (dentry->d_inode) 677 goto out_dput; 678 679 error = btrfs_may_create(dir, dentry); 680 if (error) 681 goto out_dput; 682 683 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 684 685 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) 686 goto out_up_read; 687 688 if (snap_src) { 689 error = create_snapshot(snap_src, dentry, name, namelen, 690 async_transid, readonly, inherit); 691 } else { 692 error = create_subvol(BTRFS_I(dir)->root, dentry, 693 name, namelen, async_transid, inherit); 694 } 695 if (!error) 696 fsnotify_mkdir(dir, dentry); 697 out_up_read: 698 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 699 out_dput: 700 dput(dentry); 701 out_unlock: 702 mutex_unlock(&dir->i_mutex); 703 return error; 704 } 705 706 /* 707 * When we're defragging a range, we don't want to kick it off again 708 * if it is really just waiting for delalloc to send it down. 709 * If we find a nice big extent or delalloc range for the bytes in the 710 * file you want to defrag, we return 0 to let you know to skip this 711 * part of the file 712 */ 713 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh) 714 { 715 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 716 struct extent_map *em = NULL; 717 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 718 u64 end; 719 720 read_lock(&em_tree->lock); 721 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); 722 read_unlock(&em_tree->lock); 723 724 if (em) { 725 end = extent_map_end(em); 726 free_extent_map(em); 727 if (end - offset > thresh) 728 return 0; 729 } 730 /* if we already have a nice delalloc here, just stop */ 731 thresh /= 2; 732 end = count_range_bits(io_tree, &offset, offset + thresh, 733 thresh, EXTENT_DELALLOC, 1); 734 if (end >= thresh) 735 return 0; 736 return 1; 737 } 738 739 /* 740 * helper function to walk through a file and find extents 741 * newer than a specific transid, and smaller than thresh. 742 * 743 * This is used by the defragging code to find new and small 744 * extents 745 */ 746 static int find_new_extents(struct btrfs_root *root, 747 struct inode *inode, u64 newer_than, 748 u64 *off, int thresh) 749 { 750 struct btrfs_path *path; 751 struct btrfs_key min_key; 752 struct btrfs_key max_key; 753 struct extent_buffer *leaf; 754 struct btrfs_file_extent_item *extent; 755 int type; 756 int ret; 757 u64 ino = btrfs_ino(inode); 758 759 path = btrfs_alloc_path(); 760 if (!path) 761 return -ENOMEM; 762 763 min_key.objectid = ino; 764 min_key.type = BTRFS_EXTENT_DATA_KEY; 765 min_key.offset = *off; 766 767 max_key.objectid = ino; 768 max_key.type = (u8)-1; 769 max_key.offset = (u64)-1; 770 771 path->keep_locks = 1; 772 773 while(1) { 774 ret = btrfs_search_forward(root, &min_key, &max_key, 775 path, 0, newer_than); 776 if (ret != 0) 777 goto none; 778 if (min_key.objectid != ino) 779 goto none; 780 if (min_key.type != BTRFS_EXTENT_DATA_KEY) 781 goto none; 782 783 leaf = path->nodes[0]; 784 extent = btrfs_item_ptr(leaf, path->slots[0], 785 struct btrfs_file_extent_item); 786 787 type = btrfs_file_extent_type(leaf, extent); 788 if (type == BTRFS_FILE_EXTENT_REG && 789 btrfs_file_extent_num_bytes(leaf, extent) < thresh && 790 check_defrag_in_cache(inode, min_key.offset, thresh)) { 791 *off = min_key.offset; 792 btrfs_free_path(path); 793 return 0; 794 } 795 796 if (min_key.offset == (u64)-1) 797 goto none; 798 799 min_key.offset++; 800 btrfs_release_path(path); 801 } 802 none: 803 btrfs_free_path(path); 804 return -ENOENT; 805 } 806 807 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start) 808 { 809 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 810 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 811 struct extent_map *em; 812 u64 len = PAGE_CACHE_SIZE; 813 814 /* 815 * hopefully we have this extent in the tree already, try without 816 * the full extent lock 817 */ 818 read_lock(&em_tree->lock); 819 em = lookup_extent_mapping(em_tree, start, len); 820 read_unlock(&em_tree->lock); 821 822 if (!em) { 823 /* get the big lock and read metadata off disk */ 824 lock_extent(io_tree, start, start + len - 1); 825 em = btrfs_get_extent(inode, NULL, 0, start, len, 0); 826 unlock_extent(io_tree, start, start + len - 1); 827 828 if (IS_ERR(em)) 829 return NULL; 830 } 831 832 return em; 833 } 834 835 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) 836 { 837 struct extent_map *next; 838 bool ret = true; 839 840 /* this is the last extent */ 841 if (em->start + em->len >= i_size_read(inode)) 842 return false; 843 844 next = defrag_lookup_extent(inode, em->start + em->len); 845 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) 846 ret = false; 847 848 free_extent_map(next); 849 return ret; 850 } 851 852 static int should_defrag_range(struct inode *inode, u64 start, int thresh, 853 u64 *last_len, u64 *skip, u64 *defrag_end, 854 int compress) 855 { 856 struct extent_map *em; 857 int ret = 1; 858 bool next_mergeable = true; 859 860 /* 861 * make sure that once we start defragging an extent, we keep on 862 * defragging it 863 */ 864 if (start < *defrag_end) 865 return 1; 866 867 *skip = 0; 868 869 em = defrag_lookup_extent(inode, start); 870 if (!em) 871 return 0; 872 873 /* this will cover holes, and inline extents */ 874 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 875 ret = 0; 876 goto out; 877 } 878 879 next_mergeable = defrag_check_next_extent(inode, em); 880 881 /* 882 * we hit a real extent, if it is big or the next extent is not a 883 * real extent, don't bother defragging it 884 */ 885 if (!compress && (*last_len == 0 || *last_len >= thresh) && 886 (em->len >= thresh || !next_mergeable)) 887 ret = 0; 888 out: 889 /* 890 * last_len ends up being a counter of how many bytes we've defragged. 891 * every time we choose not to defrag an extent, we reset *last_len 892 * so that the next tiny extent will force a defrag. 893 * 894 * The end result of this is that tiny extents before a single big 895 * extent will force at least part of that big extent to be defragged. 896 */ 897 if (ret) { 898 *defrag_end = extent_map_end(em); 899 } else { 900 *last_len = 0; 901 *skip = extent_map_end(em); 902 *defrag_end = 0; 903 } 904 905 free_extent_map(em); 906 return ret; 907 } 908 909 /* 910 * it doesn't do much good to defrag one or two pages 911 * at a time. This pulls in a nice chunk of pages 912 * to COW and defrag. 913 * 914 * It also makes sure the delalloc code has enough 915 * dirty data to avoid making new small extents as part 916 * of the defrag 917 * 918 * It's a good idea to start RA on this range 919 * before calling this. 920 */ 921 static int cluster_pages_for_defrag(struct inode *inode, 922 struct page **pages, 923 unsigned long start_index, 924 int num_pages) 925 { 926 unsigned long file_end; 927 u64 isize = i_size_read(inode); 928 u64 page_start; 929 u64 page_end; 930 u64 page_cnt; 931 int ret; 932 int i; 933 int i_done; 934 struct btrfs_ordered_extent *ordered; 935 struct extent_state *cached_state = NULL; 936 struct extent_io_tree *tree; 937 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 938 939 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 940 if (!isize || start_index > file_end) 941 return 0; 942 943 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); 944 945 ret = btrfs_delalloc_reserve_space(inode, 946 page_cnt << PAGE_CACHE_SHIFT); 947 if (ret) 948 return ret; 949 i_done = 0; 950 tree = &BTRFS_I(inode)->io_tree; 951 952 /* step one, lock all the pages */ 953 for (i = 0; i < page_cnt; i++) { 954 struct page *page; 955 again: 956 page = find_or_create_page(inode->i_mapping, 957 start_index + i, mask); 958 if (!page) 959 break; 960 961 page_start = page_offset(page); 962 page_end = page_start + PAGE_CACHE_SIZE - 1; 963 while (1) { 964 lock_extent(tree, page_start, page_end); 965 ordered = btrfs_lookup_ordered_extent(inode, 966 page_start); 967 unlock_extent(tree, page_start, page_end); 968 if (!ordered) 969 break; 970 971 unlock_page(page); 972 btrfs_start_ordered_extent(inode, ordered, 1); 973 btrfs_put_ordered_extent(ordered); 974 lock_page(page); 975 /* 976 * we unlocked the page above, so we need check if 977 * it was released or not. 978 */ 979 if (page->mapping != inode->i_mapping) { 980 unlock_page(page); 981 page_cache_release(page); 982 goto again; 983 } 984 } 985 986 if (!PageUptodate(page)) { 987 btrfs_readpage(NULL, page); 988 lock_page(page); 989 if (!PageUptodate(page)) { 990 unlock_page(page); 991 page_cache_release(page); 992 ret = -EIO; 993 break; 994 } 995 } 996 997 if (page->mapping != inode->i_mapping) { 998 unlock_page(page); 999 page_cache_release(page); 1000 goto again; 1001 } 1002 1003 pages[i] = page; 1004 i_done++; 1005 } 1006 if (!i_done || ret) 1007 goto out; 1008 1009 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1010 goto out; 1011 1012 /* 1013 * so now we have a nice long stream of locked 1014 * and up to date pages, lets wait on them 1015 */ 1016 for (i = 0; i < i_done; i++) 1017 wait_on_page_writeback(pages[i]); 1018 1019 page_start = page_offset(pages[0]); 1020 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; 1021 1022 lock_extent_bits(&BTRFS_I(inode)->io_tree, 1023 page_start, page_end - 1, 0, &cached_state); 1024 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 1025 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 1026 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, 1027 &cached_state, GFP_NOFS); 1028 1029 if (i_done != page_cnt) { 1030 spin_lock(&BTRFS_I(inode)->lock); 1031 BTRFS_I(inode)->outstanding_extents++; 1032 spin_unlock(&BTRFS_I(inode)->lock); 1033 btrfs_delalloc_release_space(inode, 1034 (page_cnt - i_done) << PAGE_CACHE_SHIFT); 1035 } 1036 1037 1038 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, 1039 &cached_state, GFP_NOFS); 1040 1041 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 1042 page_start, page_end - 1, &cached_state, 1043 GFP_NOFS); 1044 1045 for (i = 0; i < i_done; i++) { 1046 clear_page_dirty_for_io(pages[i]); 1047 ClearPageChecked(pages[i]); 1048 set_page_extent_mapped(pages[i]); 1049 set_page_dirty(pages[i]); 1050 unlock_page(pages[i]); 1051 page_cache_release(pages[i]); 1052 } 1053 return i_done; 1054 out: 1055 for (i = 0; i < i_done; i++) { 1056 unlock_page(pages[i]); 1057 page_cache_release(pages[i]); 1058 } 1059 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT); 1060 return ret; 1061 1062 } 1063 1064 int btrfs_defrag_file(struct inode *inode, struct file *file, 1065 struct btrfs_ioctl_defrag_range_args *range, 1066 u64 newer_than, unsigned long max_to_defrag) 1067 { 1068 struct btrfs_root *root = BTRFS_I(inode)->root; 1069 struct file_ra_state *ra = NULL; 1070 unsigned long last_index; 1071 u64 isize = i_size_read(inode); 1072 u64 last_len = 0; 1073 u64 skip = 0; 1074 u64 defrag_end = 0; 1075 u64 newer_off = range->start; 1076 unsigned long i; 1077 unsigned long ra_index = 0; 1078 int ret; 1079 int defrag_count = 0; 1080 int compress_type = BTRFS_COMPRESS_ZLIB; 1081 int extent_thresh = range->extent_thresh; 1082 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; 1083 int cluster = max_cluster; 1084 u64 new_align = ~((u64)128 * 1024 - 1); 1085 struct page **pages = NULL; 1086 1087 if (extent_thresh == 0) 1088 extent_thresh = 256 * 1024; 1089 1090 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1091 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1092 return -EINVAL; 1093 if (range->compress_type) 1094 compress_type = range->compress_type; 1095 } 1096 1097 if (isize == 0) 1098 return 0; 1099 1100 /* 1101 * if we were not given a file, allocate a readahead 1102 * context 1103 */ 1104 if (!file) { 1105 ra = kzalloc(sizeof(*ra), GFP_NOFS); 1106 if (!ra) 1107 return -ENOMEM; 1108 file_ra_state_init(ra, inode->i_mapping); 1109 } else { 1110 ra = &file->f_ra; 1111 } 1112 1113 pages = kmalloc(sizeof(struct page *) * max_cluster, 1114 GFP_NOFS); 1115 if (!pages) { 1116 ret = -ENOMEM; 1117 goto out_ra; 1118 } 1119 1120 /* find the last page to defrag */ 1121 if (range->start + range->len > range->start) { 1122 last_index = min_t(u64, isize - 1, 1123 range->start + range->len - 1) >> PAGE_CACHE_SHIFT; 1124 } else { 1125 last_index = (isize - 1) >> PAGE_CACHE_SHIFT; 1126 } 1127 1128 if (newer_than) { 1129 ret = find_new_extents(root, inode, newer_than, 1130 &newer_off, 64 * 1024); 1131 if (!ret) { 1132 range->start = newer_off; 1133 /* 1134 * we always align our defrag to help keep 1135 * the extents in the file evenly spaced 1136 */ 1137 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1138 } else 1139 goto out_ra; 1140 } else { 1141 i = range->start >> PAGE_CACHE_SHIFT; 1142 } 1143 if (!max_to_defrag) 1144 max_to_defrag = last_index + 1; 1145 1146 /* 1147 * make writeback starts from i, so the defrag range can be 1148 * written sequentially. 1149 */ 1150 if (i < inode->i_mapping->writeback_index) 1151 inode->i_mapping->writeback_index = i; 1152 1153 while (i <= last_index && defrag_count < max_to_defrag && 1154 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> 1155 PAGE_CACHE_SHIFT)) { 1156 /* 1157 * make sure we stop running if someone unmounts 1158 * the FS 1159 */ 1160 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1161 break; 1162 1163 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, 1164 extent_thresh, &last_len, &skip, 1165 &defrag_end, range->flags & 1166 BTRFS_DEFRAG_RANGE_COMPRESS)) { 1167 unsigned long next; 1168 /* 1169 * the should_defrag function tells us how much to skip 1170 * bump our counter by the suggested amount 1171 */ 1172 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 1173 i = max(i + 1, next); 1174 continue; 1175 } 1176 1177 if (!newer_than) { 1178 cluster = (PAGE_CACHE_ALIGN(defrag_end) >> 1179 PAGE_CACHE_SHIFT) - i; 1180 cluster = min(cluster, max_cluster); 1181 } else { 1182 cluster = max_cluster; 1183 } 1184 1185 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) 1186 BTRFS_I(inode)->force_compress = compress_type; 1187 1188 if (i + cluster > ra_index) { 1189 ra_index = max(i, ra_index); 1190 btrfs_force_ra(inode->i_mapping, ra, file, ra_index, 1191 cluster); 1192 ra_index += max_cluster; 1193 } 1194 1195 mutex_lock(&inode->i_mutex); 1196 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1197 if (ret < 0) { 1198 mutex_unlock(&inode->i_mutex); 1199 goto out_ra; 1200 } 1201 1202 defrag_count += ret; 1203 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret); 1204 mutex_unlock(&inode->i_mutex); 1205 1206 if (newer_than) { 1207 if (newer_off == (u64)-1) 1208 break; 1209 1210 if (ret > 0) 1211 i += ret; 1212 1213 newer_off = max(newer_off + 1, 1214 (u64)i << PAGE_CACHE_SHIFT); 1215 1216 ret = find_new_extents(root, inode, 1217 newer_than, &newer_off, 1218 64 * 1024); 1219 if (!ret) { 1220 range->start = newer_off; 1221 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1222 } else { 1223 break; 1224 } 1225 } else { 1226 if (ret > 0) { 1227 i += ret; 1228 last_len += ret << PAGE_CACHE_SHIFT; 1229 } else { 1230 i++; 1231 last_len = 0; 1232 } 1233 } 1234 } 1235 1236 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) 1237 filemap_flush(inode->i_mapping); 1238 1239 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 1240 /* the filemap_flush will queue IO into the worker threads, but 1241 * we have to make sure the IO is actually started and that 1242 * ordered extents get created before we return 1243 */ 1244 atomic_inc(&root->fs_info->async_submit_draining); 1245 while (atomic_read(&root->fs_info->nr_async_submits) || 1246 atomic_read(&root->fs_info->async_delalloc_pages)) { 1247 wait_event(root->fs_info->async_submit_wait, 1248 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 1249 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 1250 } 1251 atomic_dec(&root->fs_info->async_submit_draining); 1252 1253 mutex_lock(&inode->i_mutex); 1254 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; 1255 mutex_unlock(&inode->i_mutex); 1256 } 1257 1258 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1259 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO); 1260 } 1261 1262 ret = defrag_count; 1263 1264 out_ra: 1265 if (!file) 1266 kfree(ra); 1267 kfree(pages); 1268 return ret; 1269 } 1270 1271 static noinline int btrfs_ioctl_resize(struct btrfs_root *root, 1272 void __user *arg) 1273 { 1274 u64 new_size; 1275 u64 old_size; 1276 u64 devid = 1; 1277 struct btrfs_ioctl_vol_args *vol_args; 1278 struct btrfs_trans_handle *trans; 1279 struct btrfs_device *device = NULL; 1280 char *sizestr; 1281 char *devstr = NULL; 1282 int ret = 0; 1283 int mod = 0; 1284 1285 if (root->fs_info->sb->s_flags & MS_RDONLY) 1286 return -EROFS; 1287 1288 if (!capable(CAP_SYS_ADMIN)) 1289 return -EPERM; 1290 1291 mutex_lock(&root->fs_info->volume_mutex); 1292 if (root->fs_info->balance_ctl) { 1293 printk(KERN_INFO "btrfs: balance in progress\n"); 1294 ret = -EINVAL; 1295 goto out; 1296 } 1297 1298 vol_args = memdup_user(arg, sizeof(*vol_args)); 1299 if (IS_ERR(vol_args)) { 1300 ret = PTR_ERR(vol_args); 1301 goto out; 1302 } 1303 1304 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1305 1306 sizestr = vol_args->name; 1307 devstr = strchr(sizestr, ':'); 1308 if (devstr) { 1309 char *end; 1310 sizestr = devstr + 1; 1311 *devstr = '\0'; 1312 devstr = vol_args->name; 1313 devid = simple_strtoull(devstr, &end, 10); 1314 printk(KERN_INFO "btrfs: resizing devid %llu\n", 1315 (unsigned long long)devid); 1316 } 1317 device = btrfs_find_device(root, devid, NULL, NULL); 1318 if (!device) { 1319 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n", 1320 (unsigned long long)devid); 1321 ret = -EINVAL; 1322 goto out_free; 1323 } 1324 if (device->fs_devices && device->fs_devices->seeding) { 1325 printk(KERN_INFO "btrfs: resizer unable to apply on " 1326 "seeding device %llu\n", 1327 (unsigned long long)devid); 1328 ret = -EINVAL; 1329 goto out_free; 1330 } 1331 1332 if (!strcmp(sizestr, "max")) 1333 new_size = device->bdev->bd_inode->i_size; 1334 else { 1335 if (sizestr[0] == '-') { 1336 mod = -1; 1337 sizestr++; 1338 } else if (sizestr[0] == '+') { 1339 mod = 1; 1340 sizestr++; 1341 } 1342 new_size = memparse(sizestr, NULL); 1343 if (new_size == 0) { 1344 ret = -EINVAL; 1345 goto out_free; 1346 } 1347 } 1348 1349 old_size = device->total_bytes; 1350 1351 if (mod < 0) { 1352 if (new_size > old_size) { 1353 ret = -EINVAL; 1354 goto out_free; 1355 } 1356 new_size = old_size - new_size; 1357 } else if (mod > 0) { 1358 new_size = old_size + new_size; 1359 } 1360 1361 if (new_size < 256 * 1024 * 1024) { 1362 ret = -EINVAL; 1363 goto out_free; 1364 } 1365 if (new_size > device->bdev->bd_inode->i_size) { 1366 ret = -EFBIG; 1367 goto out_free; 1368 } 1369 1370 do_div(new_size, root->sectorsize); 1371 new_size *= root->sectorsize; 1372 1373 printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n", 1374 rcu_str_deref(device->name), 1375 (unsigned long long)new_size); 1376 1377 if (new_size > old_size) { 1378 trans = btrfs_start_transaction(root, 0); 1379 if (IS_ERR(trans)) { 1380 ret = PTR_ERR(trans); 1381 goto out_free; 1382 } 1383 ret = btrfs_grow_device(trans, device, new_size); 1384 btrfs_commit_transaction(trans, root); 1385 } else if (new_size < old_size) { 1386 ret = btrfs_shrink_device(device, new_size); 1387 } 1388 1389 out_free: 1390 kfree(vol_args); 1391 out: 1392 mutex_unlock(&root->fs_info->volume_mutex); 1393 return ret; 1394 } 1395 1396 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1397 char *name, unsigned long fd, int subvol, 1398 u64 *transid, bool readonly, 1399 struct btrfs_qgroup_inherit **inherit) 1400 { 1401 struct file *src_file; 1402 int namelen; 1403 int ret = 0; 1404 1405 ret = mnt_want_write_file(file); 1406 if (ret) 1407 goto out; 1408 1409 namelen = strlen(name); 1410 if (strchr(name, '/')) { 1411 ret = -EINVAL; 1412 goto out_drop_write; 1413 } 1414 1415 if (name[0] == '.' && 1416 (namelen == 1 || (name[1] == '.' && namelen == 2))) { 1417 ret = -EEXIST; 1418 goto out_drop_write; 1419 } 1420 1421 if (subvol) { 1422 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1423 NULL, transid, readonly, inherit); 1424 } else { 1425 struct inode *src_inode; 1426 src_file = fget(fd); 1427 if (!src_file) { 1428 ret = -EINVAL; 1429 goto out_drop_write; 1430 } 1431 1432 src_inode = src_file->f_path.dentry->d_inode; 1433 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { 1434 printk(KERN_INFO "btrfs: Snapshot src from " 1435 "another FS\n"); 1436 ret = -EINVAL; 1437 fput(src_file); 1438 goto out_drop_write; 1439 } 1440 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1441 BTRFS_I(src_inode)->root, 1442 transid, readonly, inherit); 1443 fput(src_file); 1444 } 1445 out_drop_write: 1446 mnt_drop_write_file(file); 1447 out: 1448 return ret; 1449 } 1450 1451 static noinline int btrfs_ioctl_snap_create(struct file *file, 1452 void __user *arg, int subvol) 1453 { 1454 struct btrfs_ioctl_vol_args *vol_args; 1455 int ret; 1456 1457 vol_args = memdup_user(arg, sizeof(*vol_args)); 1458 if (IS_ERR(vol_args)) 1459 return PTR_ERR(vol_args); 1460 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1461 1462 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1463 vol_args->fd, subvol, 1464 NULL, false, NULL); 1465 1466 kfree(vol_args); 1467 return ret; 1468 } 1469 1470 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1471 void __user *arg, int subvol) 1472 { 1473 struct btrfs_ioctl_vol_args_v2 *vol_args; 1474 int ret; 1475 u64 transid = 0; 1476 u64 *ptr = NULL; 1477 bool readonly = false; 1478 struct btrfs_qgroup_inherit *inherit = NULL; 1479 1480 vol_args = memdup_user(arg, sizeof(*vol_args)); 1481 if (IS_ERR(vol_args)) 1482 return PTR_ERR(vol_args); 1483 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1484 1485 if (vol_args->flags & 1486 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | 1487 BTRFS_SUBVOL_QGROUP_INHERIT)) { 1488 ret = -EOPNOTSUPP; 1489 goto out; 1490 } 1491 1492 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1493 ptr = &transid; 1494 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1495 readonly = true; 1496 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { 1497 if (vol_args->size > PAGE_CACHE_SIZE) { 1498 ret = -EINVAL; 1499 goto out; 1500 } 1501 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); 1502 if (IS_ERR(inherit)) { 1503 ret = PTR_ERR(inherit); 1504 goto out; 1505 } 1506 } 1507 1508 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1509 vol_args->fd, subvol, ptr, 1510 readonly, &inherit); 1511 1512 if (ret == 0 && ptr && 1513 copy_to_user(arg + 1514 offsetof(struct btrfs_ioctl_vol_args_v2, 1515 transid), ptr, sizeof(*ptr))) 1516 ret = -EFAULT; 1517 out: 1518 kfree(vol_args); 1519 kfree(inherit); 1520 return ret; 1521 } 1522 1523 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1524 void __user *arg) 1525 { 1526 struct inode *inode = fdentry(file)->d_inode; 1527 struct btrfs_root *root = BTRFS_I(inode)->root; 1528 int ret = 0; 1529 u64 flags = 0; 1530 1531 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1532 return -EINVAL; 1533 1534 down_read(&root->fs_info->subvol_sem); 1535 if (btrfs_root_readonly(root)) 1536 flags |= BTRFS_SUBVOL_RDONLY; 1537 up_read(&root->fs_info->subvol_sem); 1538 1539 if (copy_to_user(arg, &flags, sizeof(flags))) 1540 ret = -EFAULT; 1541 1542 return ret; 1543 } 1544 1545 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1546 void __user *arg) 1547 { 1548 struct inode *inode = fdentry(file)->d_inode; 1549 struct btrfs_root *root = BTRFS_I(inode)->root; 1550 struct btrfs_trans_handle *trans; 1551 u64 root_flags; 1552 u64 flags; 1553 int ret = 0; 1554 1555 ret = mnt_want_write_file(file); 1556 if (ret) 1557 goto out; 1558 1559 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 1560 ret = -EINVAL; 1561 goto out_drop_write; 1562 } 1563 1564 if (copy_from_user(&flags, arg, sizeof(flags))) { 1565 ret = -EFAULT; 1566 goto out_drop_write; 1567 } 1568 1569 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) { 1570 ret = -EINVAL; 1571 goto out_drop_write; 1572 } 1573 1574 if (flags & ~BTRFS_SUBVOL_RDONLY) { 1575 ret = -EOPNOTSUPP; 1576 goto out_drop_write; 1577 } 1578 1579 if (!inode_owner_or_capable(inode)) { 1580 ret = -EACCES; 1581 goto out_drop_write; 1582 } 1583 1584 down_write(&root->fs_info->subvol_sem); 1585 1586 /* nothing to do */ 1587 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1588 goto out_drop_sem; 1589 1590 root_flags = btrfs_root_flags(&root->root_item); 1591 if (flags & BTRFS_SUBVOL_RDONLY) 1592 btrfs_set_root_flags(&root->root_item, 1593 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1594 else 1595 btrfs_set_root_flags(&root->root_item, 1596 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1597 1598 trans = btrfs_start_transaction(root, 1); 1599 if (IS_ERR(trans)) { 1600 ret = PTR_ERR(trans); 1601 goto out_reset; 1602 } 1603 1604 ret = btrfs_update_root(trans, root->fs_info->tree_root, 1605 &root->root_key, &root->root_item); 1606 1607 btrfs_commit_transaction(trans, root); 1608 out_reset: 1609 if (ret) 1610 btrfs_set_root_flags(&root->root_item, root_flags); 1611 out_drop_sem: 1612 up_write(&root->fs_info->subvol_sem); 1613 out_drop_write: 1614 mnt_drop_write_file(file); 1615 out: 1616 return ret; 1617 } 1618 1619 /* 1620 * helper to check if the subvolume references other subvolumes 1621 */ 1622 static noinline int may_destroy_subvol(struct btrfs_root *root) 1623 { 1624 struct btrfs_path *path; 1625 struct btrfs_key key; 1626 int ret; 1627 1628 path = btrfs_alloc_path(); 1629 if (!path) 1630 return -ENOMEM; 1631 1632 key.objectid = root->root_key.objectid; 1633 key.type = BTRFS_ROOT_REF_KEY; 1634 key.offset = (u64)-1; 1635 1636 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, 1637 &key, path, 0, 0); 1638 if (ret < 0) 1639 goto out; 1640 BUG_ON(ret == 0); 1641 1642 ret = 0; 1643 if (path->slots[0] > 0) { 1644 path->slots[0]--; 1645 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 1646 if (key.objectid == root->root_key.objectid && 1647 key.type == BTRFS_ROOT_REF_KEY) 1648 ret = -ENOTEMPTY; 1649 } 1650 out: 1651 btrfs_free_path(path); 1652 return ret; 1653 } 1654 1655 static noinline int key_in_sk(struct btrfs_key *key, 1656 struct btrfs_ioctl_search_key *sk) 1657 { 1658 struct btrfs_key test; 1659 int ret; 1660 1661 test.objectid = sk->min_objectid; 1662 test.type = sk->min_type; 1663 test.offset = sk->min_offset; 1664 1665 ret = btrfs_comp_cpu_keys(key, &test); 1666 if (ret < 0) 1667 return 0; 1668 1669 test.objectid = sk->max_objectid; 1670 test.type = sk->max_type; 1671 test.offset = sk->max_offset; 1672 1673 ret = btrfs_comp_cpu_keys(key, &test); 1674 if (ret > 0) 1675 return 0; 1676 return 1; 1677 } 1678 1679 static noinline int copy_to_sk(struct btrfs_root *root, 1680 struct btrfs_path *path, 1681 struct btrfs_key *key, 1682 struct btrfs_ioctl_search_key *sk, 1683 char *buf, 1684 unsigned long *sk_offset, 1685 int *num_found) 1686 { 1687 u64 found_transid; 1688 struct extent_buffer *leaf; 1689 struct btrfs_ioctl_search_header sh; 1690 unsigned long item_off; 1691 unsigned long item_len; 1692 int nritems; 1693 int i; 1694 int slot; 1695 int ret = 0; 1696 1697 leaf = path->nodes[0]; 1698 slot = path->slots[0]; 1699 nritems = btrfs_header_nritems(leaf); 1700 1701 if (btrfs_header_generation(leaf) > sk->max_transid) { 1702 i = nritems; 1703 goto advance_key; 1704 } 1705 found_transid = btrfs_header_generation(leaf); 1706 1707 for (i = slot; i < nritems; i++) { 1708 item_off = btrfs_item_ptr_offset(leaf, i); 1709 item_len = btrfs_item_size_nr(leaf, i); 1710 1711 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) 1712 item_len = 0; 1713 1714 if (sizeof(sh) + item_len + *sk_offset > 1715 BTRFS_SEARCH_ARGS_BUFSIZE) { 1716 ret = 1; 1717 goto overflow; 1718 } 1719 1720 btrfs_item_key_to_cpu(leaf, key, i); 1721 if (!key_in_sk(key, sk)) 1722 continue; 1723 1724 sh.objectid = key->objectid; 1725 sh.offset = key->offset; 1726 sh.type = key->type; 1727 sh.len = item_len; 1728 sh.transid = found_transid; 1729 1730 /* copy search result header */ 1731 memcpy(buf + *sk_offset, &sh, sizeof(sh)); 1732 *sk_offset += sizeof(sh); 1733 1734 if (item_len) { 1735 char *p = buf + *sk_offset; 1736 /* copy the item */ 1737 read_extent_buffer(leaf, p, 1738 item_off, item_len); 1739 *sk_offset += item_len; 1740 } 1741 (*num_found)++; 1742 1743 if (*num_found >= sk->nr_items) 1744 break; 1745 } 1746 advance_key: 1747 ret = 0; 1748 if (key->offset < (u64)-1 && key->offset < sk->max_offset) 1749 key->offset++; 1750 else if (key->type < (u8)-1 && key->type < sk->max_type) { 1751 key->offset = 0; 1752 key->type++; 1753 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { 1754 key->offset = 0; 1755 key->type = 0; 1756 key->objectid++; 1757 } else 1758 ret = 1; 1759 overflow: 1760 return ret; 1761 } 1762 1763 static noinline int search_ioctl(struct inode *inode, 1764 struct btrfs_ioctl_search_args *args) 1765 { 1766 struct btrfs_root *root; 1767 struct btrfs_key key; 1768 struct btrfs_key max_key; 1769 struct btrfs_path *path; 1770 struct btrfs_ioctl_search_key *sk = &args->key; 1771 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; 1772 int ret; 1773 int num_found = 0; 1774 unsigned long sk_offset = 0; 1775 1776 path = btrfs_alloc_path(); 1777 if (!path) 1778 return -ENOMEM; 1779 1780 if (sk->tree_id == 0) { 1781 /* search the root of the inode that was passed */ 1782 root = BTRFS_I(inode)->root; 1783 } else { 1784 key.objectid = sk->tree_id; 1785 key.type = BTRFS_ROOT_ITEM_KEY; 1786 key.offset = (u64)-1; 1787 root = btrfs_read_fs_root_no_name(info, &key); 1788 if (IS_ERR(root)) { 1789 printk(KERN_ERR "could not find root %llu\n", 1790 sk->tree_id); 1791 btrfs_free_path(path); 1792 return -ENOENT; 1793 } 1794 } 1795 1796 key.objectid = sk->min_objectid; 1797 key.type = sk->min_type; 1798 key.offset = sk->min_offset; 1799 1800 max_key.objectid = sk->max_objectid; 1801 max_key.type = sk->max_type; 1802 max_key.offset = sk->max_offset; 1803 1804 path->keep_locks = 1; 1805 1806 while(1) { 1807 ret = btrfs_search_forward(root, &key, &max_key, path, 0, 1808 sk->min_transid); 1809 if (ret != 0) { 1810 if (ret > 0) 1811 ret = 0; 1812 goto err; 1813 } 1814 ret = copy_to_sk(root, path, &key, sk, args->buf, 1815 &sk_offset, &num_found); 1816 btrfs_release_path(path); 1817 if (ret || num_found >= sk->nr_items) 1818 break; 1819 1820 } 1821 ret = 0; 1822 err: 1823 sk->nr_items = num_found; 1824 btrfs_free_path(path); 1825 return ret; 1826 } 1827 1828 static noinline int btrfs_ioctl_tree_search(struct file *file, 1829 void __user *argp) 1830 { 1831 struct btrfs_ioctl_search_args *args; 1832 struct inode *inode; 1833 int ret; 1834 1835 if (!capable(CAP_SYS_ADMIN)) 1836 return -EPERM; 1837 1838 args = memdup_user(argp, sizeof(*args)); 1839 if (IS_ERR(args)) 1840 return PTR_ERR(args); 1841 1842 inode = fdentry(file)->d_inode; 1843 ret = search_ioctl(inode, args); 1844 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1845 ret = -EFAULT; 1846 kfree(args); 1847 return ret; 1848 } 1849 1850 /* 1851 * Search INODE_REFs to identify path name of 'dirid' directory 1852 * in a 'tree_id' tree. and sets path name to 'name'. 1853 */ 1854 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 1855 u64 tree_id, u64 dirid, char *name) 1856 { 1857 struct btrfs_root *root; 1858 struct btrfs_key key; 1859 char *ptr; 1860 int ret = -1; 1861 int slot; 1862 int len; 1863 int total_len = 0; 1864 struct btrfs_inode_ref *iref; 1865 struct extent_buffer *l; 1866 struct btrfs_path *path; 1867 1868 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 1869 name[0]='\0'; 1870 return 0; 1871 } 1872 1873 path = btrfs_alloc_path(); 1874 if (!path) 1875 return -ENOMEM; 1876 1877 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; 1878 1879 key.objectid = tree_id; 1880 key.type = BTRFS_ROOT_ITEM_KEY; 1881 key.offset = (u64)-1; 1882 root = btrfs_read_fs_root_no_name(info, &key); 1883 if (IS_ERR(root)) { 1884 printk(KERN_ERR "could not find root %llu\n", tree_id); 1885 ret = -ENOENT; 1886 goto out; 1887 } 1888 1889 key.objectid = dirid; 1890 key.type = BTRFS_INODE_REF_KEY; 1891 key.offset = (u64)-1; 1892 1893 while(1) { 1894 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1895 if (ret < 0) 1896 goto out; 1897 1898 l = path->nodes[0]; 1899 slot = path->slots[0]; 1900 if (ret > 0 && slot > 0) 1901 slot--; 1902 btrfs_item_key_to_cpu(l, &key, slot); 1903 1904 if (ret > 0 && (key.objectid != dirid || 1905 key.type != BTRFS_INODE_REF_KEY)) { 1906 ret = -ENOENT; 1907 goto out; 1908 } 1909 1910 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 1911 len = btrfs_inode_ref_name_len(l, iref); 1912 ptr -= len + 1; 1913 total_len += len + 1; 1914 if (ptr < name) 1915 goto out; 1916 1917 *(ptr + len) = '/'; 1918 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len); 1919 1920 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 1921 break; 1922 1923 btrfs_release_path(path); 1924 key.objectid = key.offset; 1925 key.offset = (u64)-1; 1926 dirid = key.objectid; 1927 } 1928 if (ptr < name) 1929 goto out; 1930 memmove(name, ptr, total_len); 1931 name[total_len]='\0'; 1932 ret = 0; 1933 out: 1934 btrfs_free_path(path); 1935 return ret; 1936 } 1937 1938 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 1939 void __user *argp) 1940 { 1941 struct btrfs_ioctl_ino_lookup_args *args; 1942 struct inode *inode; 1943 int ret; 1944 1945 if (!capable(CAP_SYS_ADMIN)) 1946 return -EPERM; 1947 1948 args = memdup_user(argp, sizeof(*args)); 1949 if (IS_ERR(args)) 1950 return PTR_ERR(args); 1951 1952 inode = fdentry(file)->d_inode; 1953 1954 if (args->treeid == 0) 1955 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 1956 1957 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 1958 args->treeid, args->objectid, 1959 args->name); 1960 1961 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 1962 ret = -EFAULT; 1963 1964 kfree(args); 1965 return ret; 1966 } 1967 1968 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 1969 void __user *arg) 1970 { 1971 struct dentry *parent = fdentry(file); 1972 struct dentry *dentry; 1973 struct inode *dir = parent->d_inode; 1974 struct inode *inode; 1975 struct btrfs_root *root = BTRFS_I(dir)->root; 1976 struct btrfs_root *dest = NULL; 1977 struct btrfs_ioctl_vol_args *vol_args; 1978 struct btrfs_trans_handle *trans; 1979 int namelen; 1980 int ret; 1981 int err = 0; 1982 1983 vol_args = memdup_user(arg, sizeof(*vol_args)); 1984 if (IS_ERR(vol_args)) 1985 return PTR_ERR(vol_args); 1986 1987 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1988 namelen = strlen(vol_args->name); 1989 if (strchr(vol_args->name, '/') || 1990 strncmp(vol_args->name, "..", namelen) == 0) { 1991 err = -EINVAL; 1992 goto out; 1993 } 1994 1995 err = mnt_want_write_file(file); 1996 if (err) 1997 goto out; 1998 1999 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 2000 dentry = lookup_one_len(vol_args->name, parent, namelen); 2001 if (IS_ERR(dentry)) { 2002 err = PTR_ERR(dentry); 2003 goto out_unlock_dir; 2004 } 2005 2006 if (!dentry->d_inode) { 2007 err = -ENOENT; 2008 goto out_dput; 2009 } 2010 2011 inode = dentry->d_inode; 2012 dest = BTRFS_I(inode)->root; 2013 if (!capable(CAP_SYS_ADMIN)){ 2014 /* 2015 * Regular user. Only allow this with a special mount 2016 * option, when the user has write+exec access to the 2017 * subvol root, and when rmdir(2) would have been 2018 * allowed. 2019 * 2020 * Note that this is _not_ check that the subvol is 2021 * empty or doesn't contain data that we wouldn't 2022 * otherwise be able to delete. 2023 * 2024 * Users who want to delete empty subvols should try 2025 * rmdir(2). 2026 */ 2027 err = -EPERM; 2028 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 2029 goto out_dput; 2030 2031 /* 2032 * Do not allow deletion if the parent dir is the same 2033 * as the dir to be deleted. That means the ioctl 2034 * must be called on the dentry referencing the root 2035 * of the subvol, not a random directory contained 2036 * within it. 2037 */ 2038 err = -EINVAL; 2039 if (root == dest) 2040 goto out_dput; 2041 2042 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 2043 if (err) 2044 goto out_dput; 2045 2046 /* check if subvolume may be deleted by a non-root user */ 2047 err = btrfs_may_delete(dir, dentry, 1); 2048 if (err) 2049 goto out_dput; 2050 } 2051 2052 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 2053 err = -EINVAL; 2054 goto out_dput; 2055 } 2056 2057 mutex_lock(&inode->i_mutex); 2058 err = d_invalidate(dentry); 2059 if (err) 2060 goto out_unlock; 2061 2062 down_write(&root->fs_info->subvol_sem); 2063 2064 err = may_destroy_subvol(dest); 2065 if (err) 2066 goto out_up_write; 2067 2068 trans = btrfs_start_transaction(root, 0); 2069 if (IS_ERR(trans)) { 2070 err = PTR_ERR(trans); 2071 goto out_up_write; 2072 } 2073 trans->block_rsv = &root->fs_info->global_block_rsv; 2074 2075 ret = btrfs_unlink_subvol(trans, root, dir, 2076 dest->root_key.objectid, 2077 dentry->d_name.name, 2078 dentry->d_name.len); 2079 if (ret) { 2080 err = ret; 2081 btrfs_abort_transaction(trans, root, ret); 2082 goto out_end_trans; 2083 } 2084 2085 btrfs_record_root_in_trans(trans, dest); 2086 2087 memset(&dest->root_item.drop_progress, 0, 2088 sizeof(dest->root_item.drop_progress)); 2089 dest->root_item.drop_level = 0; 2090 btrfs_set_root_refs(&dest->root_item, 0); 2091 2092 if (!xchg(&dest->orphan_item_inserted, 1)) { 2093 ret = btrfs_insert_orphan_item(trans, 2094 root->fs_info->tree_root, 2095 dest->root_key.objectid); 2096 if (ret) { 2097 btrfs_abort_transaction(trans, root, ret); 2098 err = ret; 2099 goto out_end_trans; 2100 } 2101 } 2102 out_end_trans: 2103 ret = btrfs_end_transaction(trans, root); 2104 if (ret && !err) 2105 err = ret; 2106 inode->i_flags |= S_DEAD; 2107 out_up_write: 2108 up_write(&root->fs_info->subvol_sem); 2109 out_unlock: 2110 mutex_unlock(&inode->i_mutex); 2111 if (!err) { 2112 shrink_dcache_sb(root->fs_info->sb); 2113 btrfs_invalidate_inodes(dest); 2114 d_delete(dentry); 2115 } 2116 out_dput: 2117 dput(dentry); 2118 out_unlock_dir: 2119 mutex_unlock(&dir->i_mutex); 2120 mnt_drop_write_file(file); 2121 out: 2122 kfree(vol_args); 2123 return err; 2124 } 2125 2126 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 2127 { 2128 struct inode *inode = fdentry(file)->d_inode; 2129 struct btrfs_root *root = BTRFS_I(inode)->root; 2130 struct btrfs_ioctl_defrag_range_args *range; 2131 int ret; 2132 2133 if (btrfs_root_readonly(root)) 2134 return -EROFS; 2135 2136 ret = mnt_want_write_file(file); 2137 if (ret) 2138 return ret; 2139 2140 switch (inode->i_mode & S_IFMT) { 2141 case S_IFDIR: 2142 if (!capable(CAP_SYS_ADMIN)) { 2143 ret = -EPERM; 2144 goto out; 2145 } 2146 ret = btrfs_defrag_root(root, 0); 2147 if (ret) 2148 goto out; 2149 ret = btrfs_defrag_root(root->fs_info->extent_root, 0); 2150 break; 2151 case S_IFREG: 2152 if (!(file->f_mode & FMODE_WRITE)) { 2153 ret = -EINVAL; 2154 goto out; 2155 } 2156 2157 range = kzalloc(sizeof(*range), GFP_KERNEL); 2158 if (!range) { 2159 ret = -ENOMEM; 2160 goto out; 2161 } 2162 2163 if (argp) { 2164 if (copy_from_user(range, argp, 2165 sizeof(*range))) { 2166 ret = -EFAULT; 2167 kfree(range); 2168 goto out; 2169 } 2170 /* compression requires us to start the IO */ 2171 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2172 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2173 range->extent_thresh = (u32)-1; 2174 } 2175 } else { 2176 /* the rest are all set to zero by kzalloc */ 2177 range->len = (u64)-1; 2178 } 2179 ret = btrfs_defrag_file(fdentry(file)->d_inode, file, 2180 range, 0, 0); 2181 if (ret > 0) 2182 ret = 0; 2183 kfree(range); 2184 break; 2185 default: 2186 ret = -EINVAL; 2187 } 2188 out: 2189 mnt_drop_write_file(file); 2190 return ret; 2191 } 2192 2193 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 2194 { 2195 struct btrfs_ioctl_vol_args *vol_args; 2196 int ret; 2197 2198 if (!capable(CAP_SYS_ADMIN)) 2199 return -EPERM; 2200 2201 mutex_lock(&root->fs_info->volume_mutex); 2202 if (root->fs_info->balance_ctl) { 2203 printk(KERN_INFO "btrfs: balance in progress\n"); 2204 ret = -EINVAL; 2205 goto out; 2206 } 2207 2208 vol_args = memdup_user(arg, sizeof(*vol_args)); 2209 if (IS_ERR(vol_args)) { 2210 ret = PTR_ERR(vol_args); 2211 goto out; 2212 } 2213 2214 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2215 ret = btrfs_init_new_device(root, vol_args->name); 2216 2217 kfree(vol_args); 2218 out: 2219 mutex_unlock(&root->fs_info->volume_mutex); 2220 return ret; 2221 } 2222 2223 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) 2224 { 2225 struct btrfs_ioctl_vol_args *vol_args; 2226 int ret; 2227 2228 if (!capable(CAP_SYS_ADMIN)) 2229 return -EPERM; 2230 2231 if (root->fs_info->sb->s_flags & MS_RDONLY) 2232 return -EROFS; 2233 2234 mutex_lock(&root->fs_info->volume_mutex); 2235 if (root->fs_info->balance_ctl) { 2236 printk(KERN_INFO "btrfs: balance in progress\n"); 2237 ret = -EINVAL; 2238 goto out; 2239 } 2240 2241 vol_args = memdup_user(arg, sizeof(*vol_args)); 2242 if (IS_ERR(vol_args)) { 2243 ret = PTR_ERR(vol_args); 2244 goto out; 2245 } 2246 2247 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2248 ret = btrfs_rm_device(root, vol_args->name); 2249 2250 kfree(vol_args); 2251 out: 2252 mutex_unlock(&root->fs_info->volume_mutex); 2253 return ret; 2254 } 2255 2256 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) 2257 { 2258 struct btrfs_ioctl_fs_info_args *fi_args; 2259 struct btrfs_device *device; 2260 struct btrfs_device *next; 2261 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2262 int ret = 0; 2263 2264 if (!capable(CAP_SYS_ADMIN)) 2265 return -EPERM; 2266 2267 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 2268 if (!fi_args) 2269 return -ENOMEM; 2270 2271 fi_args->num_devices = fs_devices->num_devices; 2272 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); 2273 2274 mutex_lock(&fs_devices->device_list_mutex); 2275 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 2276 if (device->devid > fi_args->max_id) 2277 fi_args->max_id = device->devid; 2278 } 2279 mutex_unlock(&fs_devices->device_list_mutex); 2280 2281 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 2282 ret = -EFAULT; 2283 2284 kfree(fi_args); 2285 return ret; 2286 } 2287 2288 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) 2289 { 2290 struct btrfs_ioctl_dev_info_args *di_args; 2291 struct btrfs_device *dev; 2292 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2293 int ret = 0; 2294 char *s_uuid = NULL; 2295 char empty_uuid[BTRFS_UUID_SIZE] = {0}; 2296 2297 if (!capable(CAP_SYS_ADMIN)) 2298 return -EPERM; 2299 2300 di_args = memdup_user(arg, sizeof(*di_args)); 2301 if (IS_ERR(di_args)) 2302 return PTR_ERR(di_args); 2303 2304 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0) 2305 s_uuid = di_args->uuid; 2306 2307 mutex_lock(&fs_devices->device_list_mutex); 2308 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL); 2309 mutex_unlock(&fs_devices->device_list_mutex); 2310 2311 if (!dev) { 2312 ret = -ENODEV; 2313 goto out; 2314 } 2315 2316 di_args->devid = dev->devid; 2317 di_args->bytes_used = dev->bytes_used; 2318 di_args->total_bytes = dev->total_bytes; 2319 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 2320 if (dev->name) { 2321 struct rcu_string *name; 2322 2323 rcu_read_lock(); 2324 name = rcu_dereference(dev->name); 2325 strncpy(di_args->path, name->str, sizeof(di_args->path)); 2326 rcu_read_unlock(); 2327 di_args->path[sizeof(di_args->path) - 1] = 0; 2328 } else { 2329 di_args->path[0] = '\0'; 2330 } 2331 2332 out: 2333 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 2334 ret = -EFAULT; 2335 2336 kfree(di_args); 2337 return ret; 2338 } 2339 2340 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 2341 u64 off, u64 olen, u64 destoff) 2342 { 2343 struct inode *inode = fdentry(file)->d_inode; 2344 struct btrfs_root *root = BTRFS_I(inode)->root; 2345 struct file *src_file; 2346 struct inode *src; 2347 struct btrfs_trans_handle *trans; 2348 struct btrfs_path *path; 2349 struct extent_buffer *leaf; 2350 char *buf; 2351 struct btrfs_key key; 2352 u32 nritems; 2353 int slot; 2354 int ret; 2355 u64 len = olen; 2356 u64 bs = root->fs_info->sb->s_blocksize; 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, root, inode, 2580 new_key.offset, 2581 new_key.offset + datal, 2582 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, root, inode, 2654 new_key.offset, 2655 new_key.offset + datal, 2656 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 struct btrfs_ioctl_logical_ino_args *loi; 3214 struct btrfs_data_container *inodes = NULL; 3215 struct btrfs_path *path = NULL; 3216 3217 if (!capable(CAP_SYS_ADMIN)) 3218 return -EPERM; 3219 3220 loi = memdup_user(arg, sizeof(*loi)); 3221 if (IS_ERR(loi)) { 3222 ret = PTR_ERR(loi); 3223 loi = NULL; 3224 goto out; 3225 } 3226 3227 path = btrfs_alloc_path(); 3228 if (!path) { 3229 ret = -ENOMEM; 3230 goto out; 3231 } 3232 3233 size = min_t(u32, loi->size, 64 * 1024); 3234 inodes = init_data_container(size); 3235 if (IS_ERR(inodes)) { 3236 ret = PTR_ERR(inodes); 3237 inodes = NULL; 3238 goto out; 3239 } 3240 3241 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path, 3242 build_ino_list, inodes); 3243 if (ret == -EINVAL) 3244 ret = -ENOENT; 3245 if (ret < 0) 3246 goto out; 3247 3248 ret = copy_to_user((void *)(unsigned long)loi->inodes, 3249 (void *)(unsigned long)inodes, size); 3250 if (ret) 3251 ret = -EFAULT; 3252 3253 out: 3254 btrfs_free_path(path); 3255 vfree(inodes); 3256 kfree(loi); 3257 3258 return ret; 3259 } 3260 3261 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3262 struct btrfs_ioctl_balance_args *bargs) 3263 { 3264 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3265 3266 bargs->flags = bctl->flags; 3267 3268 if (atomic_read(&fs_info->balance_running)) 3269 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 3270 if (atomic_read(&fs_info->balance_pause_req)) 3271 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 3272 if (atomic_read(&fs_info->balance_cancel_req)) 3273 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 3274 3275 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 3276 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 3277 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 3278 3279 if (lock) { 3280 spin_lock(&fs_info->balance_lock); 3281 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3282 spin_unlock(&fs_info->balance_lock); 3283 } else { 3284 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 3285 } 3286 } 3287 3288 static long btrfs_ioctl_balance(struct file *file, void __user *arg) 3289 { 3290 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 3291 struct btrfs_fs_info *fs_info = root->fs_info; 3292 struct btrfs_ioctl_balance_args *bargs; 3293 struct btrfs_balance_control *bctl; 3294 int ret; 3295 3296 if (!capable(CAP_SYS_ADMIN)) 3297 return -EPERM; 3298 3299 ret = mnt_want_write_file(file); 3300 if (ret) 3301 return ret; 3302 3303 mutex_lock(&fs_info->volume_mutex); 3304 mutex_lock(&fs_info->balance_mutex); 3305 3306 if (arg) { 3307 bargs = memdup_user(arg, sizeof(*bargs)); 3308 if (IS_ERR(bargs)) { 3309 ret = PTR_ERR(bargs); 3310 goto out; 3311 } 3312 3313 if (bargs->flags & BTRFS_BALANCE_RESUME) { 3314 if (!fs_info->balance_ctl) { 3315 ret = -ENOTCONN; 3316 goto out_bargs; 3317 } 3318 3319 bctl = fs_info->balance_ctl; 3320 spin_lock(&fs_info->balance_lock); 3321 bctl->flags |= BTRFS_BALANCE_RESUME; 3322 spin_unlock(&fs_info->balance_lock); 3323 3324 goto do_balance; 3325 } 3326 } else { 3327 bargs = NULL; 3328 } 3329 3330 if (fs_info->balance_ctl) { 3331 ret = -EINPROGRESS; 3332 goto out_bargs; 3333 } 3334 3335 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3336 if (!bctl) { 3337 ret = -ENOMEM; 3338 goto out_bargs; 3339 } 3340 3341 bctl->fs_info = fs_info; 3342 if (arg) { 3343 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 3344 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 3345 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 3346 3347 bctl->flags = bargs->flags; 3348 } else { 3349 /* balance everything - no filters */ 3350 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 3351 } 3352 3353 do_balance: 3354 ret = btrfs_balance(bctl, bargs); 3355 /* 3356 * bctl is freed in __cancel_balance or in free_fs_info if 3357 * restriper was paused all the way until unmount 3358 */ 3359 if (arg) { 3360 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3361 ret = -EFAULT; 3362 } 3363 3364 out_bargs: 3365 kfree(bargs); 3366 out: 3367 mutex_unlock(&fs_info->balance_mutex); 3368 mutex_unlock(&fs_info->volume_mutex); 3369 mnt_drop_write_file(file); 3370 return ret; 3371 } 3372 3373 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) 3374 { 3375 if (!capable(CAP_SYS_ADMIN)) 3376 return -EPERM; 3377 3378 switch (cmd) { 3379 case BTRFS_BALANCE_CTL_PAUSE: 3380 return btrfs_pause_balance(root->fs_info); 3381 case BTRFS_BALANCE_CTL_CANCEL: 3382 return btrfs_cancel_balance(root->fs_info); 3383 } 3384 3385 return -EINVAL; 3386 } 3387 3388 static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 3389 void __user *arg) 3390 { 3391 struct btrfs_fs_info *fs_info = root->fs_info; 3392 struct btrfs_ioctl_balance_args *bargs; 3393 int ret = 0; 3394 3395 if (!capable(CAP_SYS_ADMIN)) 3396 return -EPERM; 3397 3398 mutex_lock(&fs_info->balance_mutex); 3399 if (!fs_info->balance_ctl) { 3400 ret = -ENOTCONN; 3401 goto out; 3402 } 3403 3404 bargs = kzalloc(sizeof(*bargs), GFP_NOFS); 3405 if (!bargs) { 3406 ret = -ENOMEM; 3407 goto out; 3408 } 3409 3410 update_ioctl_balance_args(fs_info, 1, bargs); 3411 3412 if (copy_to_user(arg, bargs, sizeof(*bargs))) 3413 ret = -EFAULT; 3414 3415 kfree(bargs); 3416 out: 3417 mutex_unlock(&fs_info->balance_mutex); 3418 return ret; 3419 } 3420 3421 static long btrfs_ioctl_quota_ctl(struct btrfs_root *root, void __user *arg) 3422 { 3423 struct btrfs_ioctl_quota_ctl_args *sa; 3424 struct btrfs_trans_handle *trans = NULL; 3425 int ret; 3426 int err; 3427 3428 if (!capable(CAP_SYS_ADMIN)) 3429 return -EPERM; 3430 3431 if (root->fs_info->sb->s_flags & MS_RDONLY) 3432 return -EROFS; 3433 3434 sa = memdup_user(arg, sizeof(*sa)); 3435 if (IS_ERR(sa)) 3436 return PTR_ERR(sa); 3437 3438 if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) { 3439 trans = btrfs_start_transaction(root, 2); 3440 if (IS_ERR(trans)) { 3441 ret = PTR_ERR(trans); 3442 goto out; 3443 } 3444 } 3445 3446 switch (sa->cmd) { 3447 case BTRFS_QUOTA_CTL_ENABLE: 3448 ret = btrfs_quota_enable(trans, root->fs_info); 3449 break; 3450 case BTRFS_QUOTA_CTL_DISABLE: 3451 ret = btrfs_quota_disable(trans, root->fs_info); 3452 break; 3453 case BTRFS_QUOTA_CTL_RESCAN: 3454 ret = btrfs_quota_rescan(root->fs_info); 3455 break; 3456 default: 3457 ret = -EINVAL; 3458 break; 3459 } 3460 3461 if (copy_to_user(arg, sa, sizeof(*sa))) 3462 ret = -EFAULT; 3463 3464 if (trans) { 3465 err = btrfs_commit_transaction(trans, root); 3466 if (err && !ret) 3467 ret = err; 3468 } 3469 3470 out: 3471 kfree(sa); 3472 return ret; 3473 } 3474 3475 static long btrfs_ioctl_qgroup_assign(struct btrfs_root *root, void __user *arg) 3476 { 3477 struct btrfs_ioctl_qgroup_assign_args *sa; 3478 struct btrfs_trans_handle *trans; 3479 int ret; 3480 int err; 3481 3482 if (!capable(CAP_SYS_ADMIN)) 3483 return -EPERM; 3484 3485 if (root->fs_info->sb->s_flags & MS_RDONLY) 3486 return -EROFS; 3487 3488 sa = memdup_user(arg, sizeof(*sa)); 3489 if (IS_ERR(sa)) 3490 return PTR_ERR(sa); 3491 3492 trans = btrfs_join_transaction(root); 3493 if (IS_ERR(trans)) { 3494 ret = PTR_ERR(trans); 3495 goto out; 3496 } 3497 3498 /* FIXME: check if the IDs really exist */ 3499 if (sa->assign) { 3500 ret = btrfs_add_qgroup_relation(trans, root->fs_info, 3501 sa->src, sa->dst); 3502 } else { 3503 ret = btrfs_del_qgroup_relation(trans, root->fs_info, 3504 sa->src, sa->dst); 3505 } 3506 3507 err = btrfs_end_transaction(trans, root); 3508 if (err && !ret) 3509 ret = err; 3510 3511 out: 3512 kfree(sa); 3513 return ret; 3514 } 3515 3516 static long btrfs_ioctl_qgroup_create(struct btrfs_root *root, void __user *arg) 3517 { 3518 struct btrfs_ioctl_qgroup_create_args *sa; 3519 struct btrfs_trans_handle *trans; 3520 int ret; 3521 int err; 3522 3523 if (!capable(CAP_SYS_ADMIN)) 3524 return -EPERM; 3525 3526 if (root->fs_info->sb->s_flags & MS_RDONLY) 3527 return -EROFS; 3528 3529 sa = memdup_user(arg, sizeof(*sa)); 3530 if (IS_ERR(sa)) 3531 return PTR_ERR(sa); 3532 3533 trans = btrfs_join_transaction(root); 3534 if (IS_ERR(trans)) { 3535 ret = PTR_ERR(trans); 3536 goto out; 3537 } 3538 3539 /* FIXME: check if the IDs really exist */ 3540 if (sa->create) { 3541 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid, 3542 NULL); 3543 } else { 3544 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid); 3545 } 3546 3547 err = btrfs_end_transaction(trans, root); 3548 if (err && !ret) 3549 ret = err; 3550 3551 out: 3552 kfree(sa); 3553 return ret; 3554 } 3555 3556 static long btrfs_ioctl_qgroup_limit(struct btrfs_root *root, void __user *arg) 3557 { 3558 struct btrfs_ioctl_qgroup_limit_args *sa; 3559 struct btrfs_trans_handle *trans; 3560 int ret; 3561 int err; 3562 u64 qgroupid; 3563 3564 if (!capable(CAP_SYS_ADMIN)) 3565 return -EPERM; 3566 3567 if (root->fs_info->sb->s_flags & MS_RDONLY) 3568 return -EROFS; 3569 3570 sa = memdup_user(arg, sizeof(*sa)); 3571 if (IS_ERR(sa)) 3572 return PTR_ERR(sa); 3573 3574 trans = btrfs_join_transaction(root); 3575 if (IS_ERR(trans)) { 3576 ret = PTR_ERR(trans); 3577 goto out; 3578 } 3579 3580 qgroupid = sa->qgroupid; 3581 if (!qgroupid) { 3582 /* take the current subvol as qgroup */ 3583 qgroupid = root->root_key.objectid; 3584 } 3585 3586 /* FIXME: check if the IDs really exist */ 3587 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim); 3588 3589 err = btrfs_end_transaction(trans, root); 3590 if (err && !ret) 3591 ret = err; 3592 3593 out: 3594 kfree(sa); 3595 return ret; 3596 } 3597 3598 static long btrfs_ioctl_set_received_subvol(struct file *file, 3599 void __user *arg) 3600 { 3601 struct btrfs_ioctl_received_subvol_args *sa = NULL; 3602 struct inode *inode = fdentry(file)->d_inode; 3603 struct btrfs_root *root = BTRFS_I(inode)->root; 3604 struct btrfs_root_item *root_item = &root->root_item; 3605 struct btrfs_trans_handle *trans; 3606 struct timespec ct = CURRENT_TIME; 3607 int ret = 0; 3608 3609 ret = mnt_want_write_file(file); 3610 if (ret < 0) 3611 return ret; 3612 3613 down_write(&root->fs_info->subvol_sem); 3614 3615 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 3616 ret = -EINVAL; 3617 goto out; 3618 } 3619 3620 if (btrfs_root_readonly(root)) { 3621 ret = -EROFS; 3622 goto out; 3623 } 3624 3625 if (!inode_owner_or_capable(inode)) { 3626 ret = -EACCES; 3627 goto out; 3628 } 3629 3630 sa = memdup_user(arg, sizeof(*sa)); 3631 if (IS_ERR(sa)) { 3632 ret = PTR_ERR(sa); 3633 sa = NULL; 3634 goto out; 3635 } 3636 3637 trans = btrfs_start_transaction(root, 1); 3638 if (IS_ERR(trans)) { 3639 ret = PTR_ERR(trans); 3640 trans = NULL; 3641 goto out; 3642 } 3643 3644 sa->rtransid = trans->transid; 3645 sa->rtime.sec = ct.tv_sec; 3646 sa->rtime.nsec = ct.tv_nsec; 3647 3648 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); 3649 btrfs_set_root_stransid(root_item, sa->stransid); 3650 btrfs_set_root_rtransid(root_item, sa->rtransid); 3651 root_item->stime.sec = cpu_to_le64(sa->stime.sec); 3652 root_item->stime.nsec = cpu_to_le32(sa->stime.nsec); 3653 root_item->rtime.sec = cpu_to_le64(sa->rtime.sec); 3654 root_item->rtime.nsec = cpu_to_le32(sa->rtime.nsec); 3655 3656 ret = btrfs_update_root(trans, root->fs_info->tree_root, 3657 &root->root_key, &root->root_item); 3658 if (ret < 0) { 3659 btrfs_end_transaction(trans, root); 3660 trans = NULL; 3661 goto out; 3662 } else { 3663 ret = btrfs_commit_transaction(trans, root); 3664 if (ret < 0) 3665 goto out; 3666 } 3667 3668 ret = copy_to_user(arg, sa, sizeof(*sa)); 3669 if (ret) 3670 ret = -EFAULT; 3671 3672 out: 3673 kfree(sa); 3674 up_write(&root->fs_info->subvol_sem); 3675 mnt_drop_write_file(file); 3676 return ret; 3677 } 3678 3679 long btrfs_ioctl(struct file *file, unsigned int 3680 cmd, unsigned long arg) 3681 { 3682 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; 3683 void __user *argp = (void __user *)arg; 3684 3685 switch (cmd) { 3686 case FS_IOC_GETFLAGS: 3687 return btrfs_ioctl_getflags(file, argp); 3688 case FS_IOC_SETFLAGS: 3689 return btrfs_ioctl_setflags(file, argp); 3690 case FS_IOC_GETVERSION: 3691 return btrfs_ioctl_getversion(file, argp); 3692 case FITRIM: 3693 return btrfs_ioctl_fitrim(file, argp); 3694 case BTRFS_IOC_SNAP_CREATE: 3695 return btrfs_ioctl_snap_create(file, argp, 0); 3696 case BTRFS_IOC_SNAP_CREATE_V2: 3697 return btrfs_ioctl_snap_create_v2(file, argp, 0); 3698 case BTRFS_IOC_SUBVOL_CREATE: 3699 return btrfs_ioctl_snap_create(file, argp, 1); 3700 case BTRFS_IOC_SUBVOL_CREATE_V2: 3701 return btrfs_ioctl_snap_create_v2(file, argp, 1); 3702 case BTRFS_IOC_SNAP_DESTROY: 3703 return btrfs_ioctl_snap_destroy(file, argp); 3704 case BTRFS_IOC_SUBVOL_GETFLAGS: 3705 return btrfs_ioctl_subvol_getflags(file, argp); 3706 case BTRFS_IOC_SUBVOL_SETFLAGS: 3707 return btrfs_ioctl_subvol_setflags(file, argp); 3708 case BTRFS_IOC_DEFAULT_SUBVOL: 3709 return btrfs_ioctl_default_subvol(file, argp); 3710 case BTRFS_IOC_DEFRAG: 3711 return btrfs_ioctl_defrag(file, NULL); 3712 case BTRFS_IOC_DEFRAG_RANGE: 3713 return btrfs_ioctl_defrag(file, argp); 3714 case BTRFS_IOC_RESIZE: 3715 return btrfs_ioctl_resize(root, argp); 3716 case BTRFS_IOC_ADD_DEV: 3717 return btrfs_ioctl_add_dev(root, argp); 3718 case BTRFS_IOC_RM_DEV: 3719 return btrfs_ioctl_rm_dev(root, argp); 3720 case BTRFS_IOC_FS_INFO: 3721 return btrfs_ioctl_fs_info(root, argp); 3722 case BTRFS_IOC_DEV_INFO: 3723 return btrfs_ioctl_dev_info(root, argp); 3724 case BTRFS_IOC_BALANCE: 3725 return btrfs_ioctl_balance(file, NULL); 3726 case BTRFS_IOC_CLONE: 3727 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 3728 case BTRFS_IOC_CLONE_RANGE: 3729 return btrfs_ioctl_clone_range(file, argp); 3730 case BTRFS_IOC_TRANS_START: 3731 return btrfs_ioctl_trans_start(file); 3732 case BTRFS_IOC_TRANS_END: 3733 return btrfs_ioctl_trans_end(file); 3734 case BTRFS_IOC_TREE_SEARCH: 3735 return btrfs_ioctl_tree_search(file, argp); 3736 case BTRFS_IOC_INO_LOOKUP: 3737 return btrfs_ioctl_ino_lookup(file, argp); 3738 case BTRFS_IOC_INO_PATHS: 3739 return btrfs_ioctl_ino_to_path(root, argp); 3740 case BTRFS_IOC_LOGICAL_INO: 3741 return btrfs_ioctl_logical_to_ino(root, argp); 3742 case BTRFS_IOC_SPACE_INFO: 3743 return btrfs_ioctl_space_info(root, argp); 3744 case BTRFS_IOC_SYNC: 3745 btrfs_sync_fs(file->f_dentry->d_sb, 1); 3746 return 0; 3747 case BTRFS_IOC_START_SYNC: 3748 return btrfs_ioctl_start_sync(file, argp); 3749 case BTRFS_IOC_WAIT_SYNC: 3750 return btrfs_ioctl_wait_sync(file, argp); 3751 case BTRFS_IOC_SCRUB: 3752 return btrfs_ioctl_scrub(root, argp); 3753 case BTRFS_IOC_SCRUB_CANCEL: 3754 return btrfs_ioctl_scrub_cancel(root, argp); 3755 case BTRFS_IOC_SCRUB_PROGRESS: 3756 return btrfs_ioctl_scrub_progress(root, argp); 3757 case BTRFS_IOC_BALANCE_V2: 3758 return btrfs_ioctl_balance(file, argp); 3759 case BTRFS_IOC_BALANCE_CTL: 3760 return btrfs_ioctl_balance_ctl(root, arg); 3761 case BTRFS_IOC_BALANCE_PROGRESS: 3762 return btrfs_ioctl_balance_progress(root, argp); 3763 case BTRFS_IOC_SET_RECEIVED_SUBVOL: 3764 return btrfs_ioctl_set_received_subvol(file, argp); 3765 case BTRFS_IOC_SEND: 3766 return btrfs_ioctl_send(file, argp); 3767 case BTRFS_IOC_GET_DEV_STATS: 3768 return btrfs_ioctl_get_dev_stats(root, argp); 3769 case BTRFS_IOC_QUOTA_CTL: 3770 return btrfs_ioctl_quota_ctl(root, argp); 3771 case BTRFS_IOC_QGROUP_ASSIGN: 3772 return btrfs_ioctl_qgroup_assign(root, argp); 3773 case BTRFS_IOC_QGROUP_CREATE: 3774 return btrfs_ioctl_qgroup_create(root, argp); 3775 case BTRFS_IOC_QGROUP_LIMIT: 3776 return btrfs_ioctl_qgroup_limit(root, argp); 3777 } 3778 3779 return -ENOTTY; 3780 } 3781