1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 19 #include <linux/kernel.h> 20 #include <linux/bio.h> 21 #include <linux/buffer_head.h> 22 #include <linux/file.h> 23 #include <linux/fs.h> 24 #include <linux/fsnotify.h> 25 #include <linux/pagemap.h> 26 #include <linux/highmem.h> 27 #include <linux/time.h> 28 #include <linux/init.h> 29 #include <linux/string.h> 30 #include <linux/backing-dev.h> 31 #include <linux/mount.h> 32 #include <linux/mpage.h> 33 #include <linux/namei.h> 34 #include <linux/swap.h> 35 #include <linux/writeback.h> 36 #include <linux/statfs.h> 37 #include <linux/compat.h> 38 #include <linux/bit_spinlock.h> 39 #include <linux/security.h> 40 #include <linux/xattr.h> 41 #include <linux/vmalloc.h> 42 #include <linux/slab.h> 43 #include <linux/blkdev.h> 44 #include <linux/uuid.h> 45 #include <linux/btrfs.h> 46 #include <linux/uaccess.h> 47 #include "ctree.h" 48 #include "disk-io.h" 49 #include "transaction.h" 50 #include "btrfs_inode.h" 51 #include "print-tree.h" 52 #include "volumes.h" 53 #include "locking.h" 54 #include "inode-map.h" 55 #include "backref.h" 56 #include "rcu-string.h" 57 #include "send.h" 58 #include "dev-replace.h" 59 #include "props.h" 60 #include "sysfs.h" 61 #include "qgroup.h" 62 63 #ifdef CONFIG_64BIT 64 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI 65 * structures are incorrect, as the timespec structure from userspace 66 * is 4 bytes too small. We define these alternatives here to teach 67 * the kernel about the 32-bit struct packing. 68 */ 69 struct btrfs_ioctl_timespec_32 { 70 __u64 sec; 71 __u32 nsec; 72 } __attribute__ ((__packed__)); 73 74 struct btrfs_ioctl_received_subvol_args_32 { 75 char uuid[BTRFS_UUID_SIZE]; /* in */ 76 __u64 stransid; /* in */ 77 __u64 rtransid; /* out */ 78 struct btrfs_ioctl_timespec_32 stime; /* in */ 79 struct btrfs_ioctl_timespec_32 rtime; /* out */ 80 __u64 flags; /* in */ 81 __u64 reserved[16]; /* in */ 82 } __attribute__ ((__packed__)); 83 84 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \ 85 struct btrfs_ioctl_received_subvol_args_32) 86 #endif 87 88 89 static int btrfs_clone(struct inode *src, struct inode *inode, 90 u64 off, u64 olen, u64 olen_aligned, u64 destoff); 91 92 /* Mask out flags that are inappropriate for the given type of inode. */ 93 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags) 94 { 95 if (S_ISDIR(mode)) 96 return flags; 97 else if (S_ISREG(mode)) 98 return flags & ~FS_DIRSYNC_FL; 99 else 100 return flags & (FS_NODUMP_FL | FS_NOATIME_FL); 101 } 102 103 /* 104 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl. 105 */ 106 static unsigned int btrfs_flags_to_ioctl(unsigned int flags) 107 { 108 unsigned int iflags = 0; 109 110 if (flags & BTRFS_INODE_SYNC) 111 iflags |= FS_SYNC_FL; 112 if (flags & BTRFS_INODE_IMMUTABLE) 113 iflags |= FS_IMMUTABLE_FL; 114 if (flags & BTRFS_INODE_APPEND) 115 iflags |= FS_APPEND_FL; 116 if (flags & BTRFS_INODE_NODUMP) 117 iflags |= FS_NODUMP_FL; 118 if (flags & BTRFS_INODE_NOATIME) 119 iflags |= FS_NOATIME_FL; 120 if (flags & BTRFS_INODE_DIRSYNC) 121 iflags |= FS_DIRSYNC_FL; 122 if (flags & BTRFS_INODE_NODATACOW) 123 iflags |= FS_NOCOW_FL; 124 125 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS)) 126 iflags |= FS_COMPR_FL; 127 else if (flags & BTRFS_INODE_NOCOMPRESS) 128 iflags |= FS_NOCOMP_FL; 129 130 return iflags; 131 } 132 133 /* 134 * Update inode->i_flags based on the btrfs internal flags. 135 */ 136 void btrfs_update_iflags(struct inode *inode) 137 { 138 struct btrfs_inode *ip = BTRFS_I(inode); 139 unsigned int new_fl = 0; 140 141 if (ip->flags & BTRFS_INODE_SYNC) 142 new_fl |= S_SYNC; 143 if (ip->flags & BTRFS_INODE_IMMUTABLE) 144 new_fl |= S_IMMUTABLE; 145 if (ip->flags & BTRFS_INODE_APPEND) 146 new_fl |= S_APPEND; 147 if (ip->flags & BTRFS_INODE_NOATIME) 148 new_fl |= S_NOATIME; 149 if (ip->flags & BTRFS_INODE_DIRSYNC) 150 new_fl |= S_DIRSYNC; 151 152 set_mask_bits(&inode->i_flags, 153 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC, 154 new_fl); 155 } 156 157 /* 158 * Inherit flags from the parent inode. 159 * 160 * Currently only the compression flags and the cow flags are inherited. 161 */ 162 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) 163 { 164 unsigned int flags; 165 166 if (!dir) 167 return; 168 169 flags = BTRFS_I(dir)->flags; 170 171 if (flags & BTRFS_INODE_NOCOMPRESS) { 172 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS; 173 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; 174 } else if (flags & BTRFS_INODE_COMPRESS) { 175 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS; 176 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS; 177 } 178 179 if (flags & BTRFS_INODE_NODATACOW) { 180 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; 181 if (S_ISREG(inode->i_mode)) 182 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; 183 } 184 185 btrfs_update_iflags(inode); 186 } 187 188 static int btrfs_ioctl_getflags(struct file *file, void __user *arg) 189 { 190 struct btrfs_inode *ip = BTRFS_I(file_inode(file)); 191 unsigned int flags = btrfs_flags_to_ioctl(ip->flags); 192 193 if (copy_to_user(arg, &flags, sizeof(flags))) 194 return -EFAULT; 195 return 0; 196 } 197 198 static int check_flags(unsigned int flags) 199 { 200 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ 201 FS_NOATIME_FL | FS_NODUMP_FL | \ 202 FS_SYNC_FL | FS_DIRSYNC_FL | \ 203 FS_NOCOMP_FL | FS_COMPR_FL | 204 FS_NOCOW_FL)) 205 return -EOPNOTSUPP; 206 207 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) 208 return -EINVAL; 209 210 return 0; 211 } 212 213 static int btrfs_ioctl_setflags(struct file *file, void __user *arg) 214 { 215 struct inode *inode = file_inode(file); 216 struct btrfs_inode *ip = BTRFS_I(inode); 217 struct btrfs_root *root = ip->root; 218 struct btrfs_trans_handle *trans; 219 unsigned int flags, oldflags; 220 int ret; 221 u64 ip_oldflags; 222 unsigned int i_oldflags; 223 umode_t mode; 224 225 if (!inode_owner_or_capable(inode)) 226 return -EPERM; 227 228 if (btrfs_root_readonly(root)) 229 return -EROFS; 230 231 if (copy_from_user(&flags, arg, sizeof(flags))) 232 return -EFAULT; 233 234 ret = check_flags(flags); 235 if (ret) 236 return ret; 237 238 ret = mnt_want_write_file(file); 239 if (ret) 240 return ret; 241 242 mutex_lock(&inode->i_mutex); 243 244 ip_oldflags = ip->flags; 245 i_oldflags = inode->i_flags; 246 mode = inode->i_mode; 247 248 flags = btrfs_mask_flags(inode->i_mode, flags); 249 oldflags = btrfs_flags_to_ioctl(ip->flags); 250 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { 251 if (!capable(CAP_LINUX_IMMUTABLE)) { 252 ret = -EPERM; 253 goto out_unlock; 254 } 255 } 256 257 if (flags & FS_SYNC_FL) 258 ip->flags |= BTRFS_INODE_SYNC; 259 else 260 ip->flags &= ~BTRFS_INODE_SYNC; 261 if (flags & FS_IMMUTABLE_FL) 262 ip->flags |= BTRFS_INODE_IMMUTABLE; 263 else 264 ip->flags &= ~BTRFS_INODE_IMMUTABLE; 265 if (flags & FS_APPEND_FL) 266 ip->flags |= BTRFS_INODE_APPEND; 267 else 268 ip->flags &= ~BTRFS_INODE_APPEND; 269 if (flags & FS_NODUMP_FL) 270 ip->flags |= BTRFS_INODE_NODUMP; 271 else 272 ip->flags &= ~BTRFS_INODE_NODUMP; 273 if (flags & FS_NOATIME_FL) 274 ip->flags |= BTRFS_INODE_NOATIME; 275 else 276 ip->flags &= ~BTRFS_INODE_NOATIME; 277 if (flags & FS_DIRSYNC_FL) 278 ip->flags |= BTRFS_INODE_DIRSYNC; 279 else 280 ip->flags &= ~BTRFS_INODE_DIRSYNC; 281 if (flags & FS_NOCOW_FL) { 282 if (S_ISREG(mode)) { 283 /* 284 * It's safe to turn csums off here, no extents exist. 285 * Otherwise we want the flag to reflect the real COW 286 * status of the file and will not set it. 287 */ 288 if (inode->i_size == 0) 289 ip->flags |= BTRFS_INODE_NODATACOW 290 | BTRFS_INODE_NODATASUM; 291 } else { 292 ip->flags |= BTRFS_INODE_NODATACOW; 293 } 294 } else { 295 /* 296 * Revert back under same assuptions as above 297 */ 298 if (S_ISREG(mode)) { 299 if (inode->i_size == 0) 300 ip->flags &= ~(BTRFS_INODE_NODATACOW 301 | BTRFS_INODE_NODATASUM); 302 } else { 303 ip->flags &= ~BTRFS_INODE_NODATACOW; 304 } 305 } 306 307 /* 308 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS 309 * flag may be changed automatically if compression code won't make 310 * things smaller. 311 */ 312 if (flags & FS_NOCOMP_FL) { 313 ip->flags &= ~BTRFS_INODE_COMPRESS; 314 ip->flags |= BTRFS_INODE_NOCOMPRESS; 315 316 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0); 317 if (ret && ret != -ENODATA) 318 goto out_drop; 319 } else if (flags & FS_COMPR_FL) { 320 const char *comp; 321 322 ip->flags |= BTRFS_INODE_COMPRESS; 323 ip->flags &= ~BTRFS_INODE_NOCOMPRESS; 324 325 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO) 326 comp = "lzo"; 327 else 328 comp = "zlib"; 329 ret = btrfs_set_prop(inode, "btrfs.compression", 330 comp, strlen(comp), 0); 331 if (ret) 332 goto out_drop; 333 334 } else { 335 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0); 336 if (ret && ret != -ENODATA) 337 goto out_drop; 338 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); 339 } 340 341 trans = btrfs_start_transaction(root, 1); 342 if (IS_ERR(trans)) { 343 ret = PTR_ERR(trans); 344 goto out_drop; 345 } 346 347 btrfs_update_iflags(inode); 348 inode_inc_iversion(inode); 349 inode->i_ctime = CURRENT_TIME; 350 ret = btrfs_update_inode(trans, root, inode); 351 352 btrfs_end_transaction(trans, root); 353 out_drop: 354 if (ret) { 355 ip->flags = ip_oldflags; 356 inode->i_flags = i_oldflags; 357 } 358 359 out_unlock: 360 mutex_unlock(&inode->i_mutex); 361 mnt_drop_write_file(file); 362 return ret; 363 } 364 365 static int btrfs_ioctl_getversion(struct file *file, int __user *arg) 366 { 367 struct inode *inode = file_inode(file); 368 369 return put_user(inode->i_generation, arg); 370 } 371 372 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) 373 { 374 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb); 375 struct btrfs_device *device; 376 struct request_queue *q; 377 struct fstrim_range range; 378 u64 minlen = ULLONG_MAX; 379 u64 num_devices = 0; 380 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy); 381 int ret; 382 383 if (!capable(CAP_SYS_ADMIN)) 384 return -EPERM; 385 386 rcu_read_lock(); 387 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices, 388 dev_list) { 389 if (!device->bdev) 390 continue; 391 q = bdev_get_queue(device->bdev); 392 if (blk_queue_discard(q)) { 393 num_devices++; 394 minlen = min((u64)q->limits.discard_granularity, 395 minlen); 396 } 397 } 398 rcu_read_unlock(); 399 400 if (!num_devices) 401 return -EOPNOTSUPP; 402 if (copy_from_user(&range, arg, sizeof(range))) 403 return -EFAULT; 404 if (range.start > total_bytes || 405 range.len < fs_info->sb->s_blocksize) 406 return -EINVAL; 407 408 range.len = min(range.len, total_bytes - range.start); 409 range.minlen = max(range.minlen, minlen); 410 ret = btrfs_trim_fs(fs_info->tree_root, &range); 411 if (ret < 0) 412 return ret; 413 414 if (copy_to_user(arg, &range, sizeof(range))) 415 return -EFAULT; 416 417 return 0; 418 } 419 420 int btrfs_is_empty_uuid(u8 *uuid) 421 { 422 int i; 423 424 for (i = 0; i < BTRFS_UUID_SIZE; i++) { 425 if (uuid[i]) 426 return 0; 427 } 428 return 1; 429 } 430 431 static noinline int create_subvol(struct inode *dir, 432 struct dentry *dentry, 433 char *name, int namelen, 434 u64 *async_transid, 435 struct btrfs_qgroup_inherit *inherit) 436 { 437 struct btrfs_trans_handle *trans; 438 struct btrfs_key key; 439 struct btrfs_root_item root_item; 440 struct btrfs_inode_item *inode_item; 441 struct extent_buffer *leaf; 442 struct btrfs_root *root = BTRFS_I(dir)->root; 443 struct btrfs_root *new_root; 444 struct btrfs_block_rsv block_rsv; 445 struct timespec cur_time = CURRENT_TIME; 446 struct inode *inode; 447 int ret; 448 int err; 449 u64 objectid; 450 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; 451 u64 index = 0; 452 u64 qgroup_reserved; 453 uuid_le new_uuid; 454 455 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid); 456 if (ret) 457 return ret; 458 459 /* 460 * Don't create subvolume whose level is not zero. Or qgroup will be 461 * screwed up since it assume subvolme qgroup's level to be 0. 462 */ 463 if (btrfs_qgroup_level(objectid)) 464 return -ENOSPC; 465 466 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); 467 /* 468 * The same as the snapshot creation, please see the comment 469 * of create_snapshot(). 470 */ 471 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 472 8, &qgroup_reserved, false); 473 if (ret) 474 return ret; 475 476 trans = btrfs_start_transaction(root, 0); 477 if (IS_ERR(trans)) { 478 ret = PTR_ERR(trans); 479 btrfs_subvolume_release_metadata(root, &block_rsv, 480 qgroup_reserved); 481 return ret; 482 } 483 trans->block_rsv = &block_rsv; 484 trans->bytes_reserved = block_rsv.size; 485 486 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit); 487 if (ret) 488 goto fail; 489 490 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0); 491 if (IS_ERR(leaf)) { 492 ret = PTR_ERR(leaf); 493 goto fail; 494 } 495 496 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header)); 497 btrfs_set_header_bytenr(leaf, leaf->start); 498 btrfs_set_header_generation(leaf, trans->transid); 499 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV); 500 btrfs_set_header_owner(leaf, objectid); 501 502 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(), 503 BTRFS_FSID_SIZE); 504 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 505 btrfs_header_chunk_tree_uuid(leaf), 506 BTRFS_UUID_SIZE); 507 btrfs_mark_buffer_dirty(leaf); 508 509 memset(&root_item, 0, sizeof(root_item)); 510 511 inode_item = &root_item.inode; 512 btrfs_set_stack_inode_generation(inode_item, 1); 513 btrfs_set_stack_inode_size(inode_item, 3); 514 btrfs_set_stack_inode_nlink(inode_item, 1); 515 btrfs_set_stack_inode_nbytes(inode_item, root->nodesize); 516 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); 517 518 btrfs_set_root_flags(&root_item, 0); 519 btrfs_set_root_limit(&root_item, 0); 520 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT); 521 522 btrfs_set_root_bytenr(&root_item, leaf->start); 523 btrfs_set_root_generation(&root_item, trans->transid); 524 btrfs_set_root_level(&root_item, 0); 525 btrfs_set_root_refs(&root_item, 1); 526 btrfs_set_root_used(&root_item, leaf->len); 527 btrfs_set_root_last_snapshot(&root_item, 0); 528 529 btrfs_set_root_generation_v2(&root_item, 530 btrfs_root_generation(&root_item)); 531 uuid_le_gen(&new_uuid); 532 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE); 533 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec); 534 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec); 535 root_item.ctime = root_item.otime; 536 btrfs_set_root_ctransid(&root_item, trans->transid); 537 btrfs_set_root_otransid(&root_item, trans->transid); 538 539 btrfs_tree_unlock(leaf); 540 free_extent_buffer(leaf); 541 leaf = NULL; 542 543 btrfs_set_root_dirid(&root_item, new_dirid); 544 545 key.objectid = objectid; 546 key.offset = 0; 547 key.type = BTRFS_ROOT_ITEM_KEY; 548 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, 549 &root_item); 550 if (ret) 551 goto fail; 552 553 key.offset = (u64)-1; 554 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); 555 if (IS_ERR(new_root)) { 556 ret = PTR_ERR(new_root); 557 btrfs_abort_transaction(trans, root, ret); 558 goto fail; 559 } 560 561 btrfs_record_root_in_trans(trans, new_root); 562 563 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid); 564 if (ret) { 565 /* We potentially lose an unused inode item here */ 566 btrfs_abort_transaction(trans, root, ret); 567 goto fail; 568 } 569 570 /* 571 * insert the directory item 572 */ 573 ret = btrfs_set_inode_index(dir, &index); 574 if (ret) { 575 btrfs_abort_transaction(trans, root, ret); 576 goto fail; 577 } 578 579 ret = btrfs_insert_dir_item(trans, root, 580 name, namelen, dir, &key, 581 BTRFS_FT_DIR, index); 582 if (ret) { 583 btrfs_abort_transaction(trans, root, ret); 584 goto fail; 585 } 586 587 btrfs_i_size_write(dir, dir->i_size + namelen * 2); 588 ret = btrfs_update_inode(trans, root, dir); 589 BUG_ON(ret); 590 591 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, 592 objectid, root->root_key.objectid, 593 btrfs_ino(dir), index, name, namelen); 594 BUG_ON(ret); 595 596 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root, 597 root_item.uuid, BTRFS_UUID_KEY_SUBVOL, 598 objectid); 599 if (ret) 600 btrfs_abort_transaction(trans, root, ret); 601 602 fail: 603 trans->block_rsv = NULL; 604 trans->bytes_reserved = 0; 605 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); 606 607 if (async_transid) { 608 *async_transid = trans->transid; 609 err = btrfs_commit_transaction_async(trans, root, 1); 610 if (err) 611 err = btrfs_commit_transaction(trans, root); 612 } else { 613 err = btrfs_commit_transaction(trans, root); 614 } 615 if (err && !ret) 616 ret = err; 617 618 if (!ret) { 619 inode = btrfs_lookup_dentry(dir, dentry); 620 if (IS_ERR(inode)) 621 return PTR_ERR(inode); 622 d_instantiate(dentry, inode); 623 } 624 return ret; 625 } 626 627 static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root) 628 { 629 s64 writers; 630 DEFINE_WAIT(wait); 631 632 do { 633 prepare_to_wait(&root->subv_writers->wait, &wait, 634 TASK_UNINTERRUPTIBLE); 635 636 writers = percpu_counter_sum(&root->subv_writers->counter); 637 if (writers) 638 schedule(); 639 640 finish_wait(&root->subv_writers->wait, &wait); 641 } while (writers); 642 } 643 644 static int create_snapshot(struct btrfs_root *root, struct inode *dir, 645 struct dentry *dentry, char *name, int namelen, 646 u64 *async_transid, bool readonly, 647 struct btrfs_qgroup_inherit *inherit) 648 { 649 struct inode *inode; 650 struct btrfs_pending_snapshot *pending_snapshot; 651 struct btrfs_trans_handle *trans; 652 int ret; 653 654 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 655 return -EINVAL; 656 657 atomic_inc(&root->will_be_snapshoted); 658 smp_mb__after_atomic(); 659 btrfs_wait_for_no_snapshoting_writes(root); 660 661 ret = btrfs_start_delalloc_inodes(root, 0); 662 if (ret) 663 goto out; 664 665 btrfs_wait_ordered_extents(root, -1); 666 667 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); 668 if (!pending_snapshot) { 669 ret = -ENOMEM; 670 goto out; 671 } 672 673 btrfs_init_block_rsv(&pending_snapshot->block_rsv, 674 BTRFS_BLOCK_RSV_TEMP); 675 /* 676 * 1 - parent dir inode 677 * 2 - dir entries 678 * 1 - root item 679 * 2 - root ref/backref 680 * 1 - root of snapshot 681 * 1 - UUID item 682 */ 683 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, 684 &pending_snapshot->block_rsv, 8, 685 &pending_snapshot->qgroup_reserved, 686 false); 687 if (ret) 688 goto free; 689 690 pending_snapshot->dentry = dentry; 691 pending_snapshot->root = root; 692 pending_snapshot->readonly = readonly; 693 pending_snapshot->dir = dir; 694 pending_snapshot->inherit = inherit; 695 696 trans = btrfs_start_transaction(root, 0); 697 if (IS_ERR(trans)) { 698 ret = PTR_ERR(trans); 699 goto fail; 700 } 701 702 spin_lock(&root->fs_info->trans_lock); 703 list_add(&pending_snapshot->list, 704 &trans->transaction->pending_snapshots); 705 spin_unlock(&root->fs_info->trans_lock); 706 if (async_transid) { 707 *async_transid = trans->transid; 708 ret = btrfs_commit_transaction_async(trans, 709 root->fs_info->extent_root, 1); 710 if (ret) 711 ret = btrfs_commit_transaction(trans, root); 712 } else { 713 ret = btrfs_commit_transaction(trans, 714 root->fs_info->extent_root); 715 } 716 if (ret) 717 goto fail; 718 719 ret = pending_snapshot->error; 720 if (ret) 721 goto fail; 722 723 ret = btrfs_orphan_cleanup(pending_snapshot->snap); 724 if (ret) 725 goto fail; 726 727 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry); 728 if (IS_ERR(inode)) { 729 ret = PTR_ERR(inode); 730 goto fail; 731 } 732 733 d_instantiate(dentry, inode); 734 ret = 0; 735 fail: 736 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root, 737 &pending_snapshot->block_rsv, 738 pending_snapshot->qgroup_reserved); 739 free: 740 kfree(pending_snapshot); 741 out: 742 if (atomic_dec_and_test(&root->will_be_snapshoted)) 743 wake_up_atomic_t(&root->will_be_snapshoted); 744 return ret; 745 } 746 747 /* copy of may_delete in fs/namei.c() 748 * Check whether we can remove a link victim from directory dir, check 749 * whether the type of victim is right. 750 * 1. We can't do it if dir is read-only (done in permission()) 751 * 2. We should have write and exec permissions on dir 752 * 3. We can't remove anything from append-only dir 753 * 4. We can't do anything with immutable dir (done in permission()) 754 * 5. If the sticky bit on dir is set we should either 755 * a. be owner of dir, or 756 * b. be owner of victim, or 757 * c. have CAP_FOWNER capability 758 * 6. If the victim is append-only or immutable we can't do antyhing with 759 * links pointing to it. 760 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. 761 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. 762 * 9. We can't remove a root or mountpoint. 763 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by 764 * nfs_async_unlink(). 765 */ 766 767 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir) 768 { 769 int error; 770 771 if (d_really_is_negative(victim)) 772 return -ENOENT; 773 774 BUG_ON(d_inode(victim->d_parent) != dir); 775 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); 776 777 error = inode_permission(dir, MAY_WRITE | MAY_EXEC); 778 if (error) 779 return error; 780 if (IS_APPEND(dir)) 781 return -EPERM; 782 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) || 783 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim))) 784 return -EPERM; 785 if (isdir) { 786 if (!d_is_dir(victim)) 787 return -ENOTDIR; 788 if (IS_ROOT(victim)) 789 return -EBUSY; 790 } else if (d_is_dir(victim)) 791 return -EISDIR; 792 if (IS_DEADDIR(dir)) 793 return -ENOENT; 794 if (victim->d_flags & DCACHE_NFSFS_RENAMED) 795 return -EBUSY; 796 return 0; 797 } 798 799 /* copy of may_create in fs/namei.c() */ 800 static inline int btrfs_may_create(struct inode *dir, struct dentry *child) 801 { 802 if (d_really_is_positive(child)) 803 return -EEXIST; 804 if (IS_DEADDIR(dir)) 805 return -ENOENT; 806 return inode_permission(dir, MAY_WRITE | MAY_EXEC); 807 } 808 809 /* 810 * Create a new subvolume below @parent. This is largely modeled after 811 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup 812 * inside this filesystem so it's quite a bit simpler. 813 */ 814 static noinline int btrfs_mksubvol(struct path *parent, 815 char *name, int namelen, 816 struct btrfs_root *snap_src, 817 u64 *async_transid, bool readonly, 818 struct btrfs_qgroup_inherit *inherit) 819 { 820 struct inode *dir = d_inode(parent->dentry); 821 struct dentry *dentry; 822 int error; 823 824 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT); 825 if (error == -EINTR) 826 return error; 827 828 dentry = lookup_one_len(name, parent->dentry, namelen); 829 error = PTR_ERR(dentry); 830 if (IS_ERR(dentry)) 831 goto out_unlock; 832 833 error = -EEXIST; 834 if (d_really_is_positive(dentry)) 835 goto out_dput; 836 837 error = btrfs_may_create(dir, dentry); 838 if (error) 839 goto out_dput; 840 841 /* 842 * even if this name doesn't exist, we may get hash collisions. 843 * check for them now when we can safely fail 844 */ 845 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root, 846 dir->i_ino, name, 847 namelen); 848 if (error) 849 goto out_dput; 850 851 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 852 853 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) 854 goto out_up_read; 855 856 if (snap_src) { 857 error = create_snapshot(snap_src, dir, dentry, name, namelen, 858 async_transid, readonly, inherit); 859 } else { 860 error = create_subvol(dir, dentry, name, namelen, 861 async_transid, inherit); 862 } 863 if (!error) 864 fsnotify_mkdir(dir, dentry); 865 out_up_read: 866 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 867 out_dput: 868 dput(dentry); 869 out_unlock: 870 mutex_unlock(&dir->i_mutex); 871 return error; 872 } 873 874 /* 875 * When we're defragging a range, we don't want to kick it off again 876 * if it is really just waiting for delalloc to send it down. 877 * If we find a nice big extent or delalloc range for the bytes in the 878 * file you want to defrag, we return 0 to let you know to skip this 879 * part of the file 880 */ 881 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh) 882 { 883 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 884 struct extent_map *em = NULL; 885 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 886 u64 end; 887 888 read_lock(&em_tree->lock); 889 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); 890 read_unlock(&em_tree->lock); 891 892 if (em) { 893 end = extent_map_end(em); 894 free_extent_map(em); 895 if (end - offset > thresh) 896 return 0; 897 } 898 /* if we already have a nice delalloc here, just stop */ 899 thresh /= 2; 900 end = count_range_bits(io_tree, &offset, offset + thresh, 901 thresh, EXTENT_DELALLOC, 1); 902 if (end >= thresh) 903 return 0; 904 return 1; 905 } 906 907 /* 908 * helper function to walk through a file and find extents 909 * newer than a specific transid, and smaller than thresh. 910 * 911 * This is used by the defragging code to find new and small 912 * extents 913 */ 914 static int find_new_extents(struct btrfs_root *root, 915 struct inode *inode, u64 newer_than, 916 u64 *off, u32 thresh) 917 { 918 struct btrfs_path *path; 919 struct btrfs_key min_key; 920 struct extent_buffer *leaf; 921 struct btrfs_file_extent_item *extent; 922 int type; 923 int ret; 924 u64 ino = btrfs_ino(inode); 925 926 path = btrfs_alloc_path(); 927 if (!path) 928 return -ENOMEM; 929 930 min_key.objectid = ino; 931 min_key.type = BTRFS_EXTENT_DATA_KEY; 932 min_key.offset = *off; 933 934 while (1) { 935 ret = btrfs_search_forward(root, &min_key, path, newer_than); 936 if (ret != 0) 937 goto none; 938 process_slot: 939 if (min_key.objectid != ino) 940 goto none; 941 if (min_key.type != BTRFS_EXTENT_DATA_KEY) 942 goto none; 943 944 leaf = path->nodes[0]; 945 extent = btrfs_item_ptr(leaf, path->slots[0], 946 struct btrfs_file_extent_item); 947 948 type = btrfs_file_extent_type(leaf, extent); 949 if (type == BTRFS_FILE_EXTENT_REG && 950 btrfs_file_extent_num_bytes(leaf, extent) < thresh && 951 check_defrag_in_cache(inode, min_key.offset, thresh)) { 952 *off = min_key.offset; 953 btrfs_free_path(path); 954 return 0; 955 } 956 957 path->slots[0]++; 958 if (path->slots[0] < btrfs_header_nritems(leaf)) { 959 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]); 960 goto process_slot; 961 } 962 963 if (min_key.offset == (u64)-1) 964 goto none; 965 966 min_key.offset++; 967 btrfs_release_path(path); 968 } 969 none: 970 btrfs_free_path(path); 971 return -ENOENT; 972 } 973 974 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start) 975 { 976 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 977 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 978 struct extent_map *em; 979 u64 len = PAGE_CACHE_SIZE; 980 981 /* 982 * hopefully we have this extent in the tree already, try without 983 * the full extent lock 984 */ 985 read_lock(&em_tree->lock); 986 em = lookup_extent_mapping(em_tree, start, len); 987 read_unlock(&em_tree->lock); 988 989 if (!em) { 990 struct extent_state *cached = NULL; 991 u64 end = start + len - 1; 992 993 /* get the big lock and read metadata off disk */ 994 lock_extent_bits(io_tree, start, end, 0, &cached); 995 em = btrfs_get_extent(inode, NULL, 0, start, len, 0); 996 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS); 997 998 if (IS_ERR(em)) 999 return NULL; 1000 } 1001 1002 return em; 1003 } 1004 1005 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) 1006 { 1007 struct extent_map *next; 1008 bool ret = true; 1009 1010 /* this is the last extent */ 1011 if (em->start + em->len >= i_size_read(inode)) 1012 return false; 1013 1014 next = defrag_lookup_extent(inode, em->start + em->len); 1015 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) 1016 ret = false; 1017 else if ((em->block_start + em->block_len == next->block_start) && 1018 (em->block_len > 128 * 1024 && next->block_len > 128 * 1024)) 1019 ret = false; 1020 1021 free_extent_map(next); 1022 return ret; 1023 } 1024 1025 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh, 1026 u64 *last_len, u64 *skip, u64 *defrag_end, 1027 int compress) 1028 { 1029 struct extent_map *em; 1030 int ret = 1; 1031 bool next_mergeable = true; 1032 1033 /* 1034 * make sure that once we start defragging an extent, we keep on 1035 * defragging it 1036 */ 1037 if (start < *defrag_end) 1038 return 1; 1039 1040 *skip = 0; 1041 1042 em = defrag_lookup_extent(inode, start); 1043 if (!em) 1044 return 0; 1045 1046 /* this will cover holes, and inline extents */ 1047 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 1048 ret = 0; 1049 goto out; 1050 } 1051 1052 next_mergeable = defrag_check_next_extent(inode, em); 1053 /* 1054 * we hit a real extent, if it is big or the next extent is not a 1055 * real extent, don't bother defragging it 1056 */ 1057 if (!compress && (*last_len == 0 || *last_len >= thresh) && 1058 (em->len >= thresh || !next_mergeable)) 1059 ret = 0; 1060 out: 1061 /* 1062 * last_len ends up being a counter of how many bytes we've defragged. 1063 * every time we choose not to defrag an extent, we reset *last_len 1064 * so that the next tiny extent will force a defrag. 1065 * 1066 * The end result of this is that tiny extents before a single big 1067 * extent will force at least part of that big extent to be defragged. 1068 */ 1069 if (ret) { 1070 *defrag_end = extent_map_end(em); 1071 } else { 1072 *last_len = 0; 1073 *skip = extent_map_end(em); 1074 *defrag_end = 0; 1075 } 1076 1077 free_extent_map(em); 1078 return ret; 1079 } 1080 1081 /* 1082 * it doesn't do much good to defrag one or two pages 1083 * at a time. This pulls in a nice chunk of pages 1084 * to COW and defrag. 1085 * 1086 * It also makes sure the delalloc code has enough 1087 * dirty data to avoid making new small extents as part 1088 * of the defrag 1089 * 1090 * It's a good idea to start RA on this range 1091 * before calling this. 1092 */ 1093 static int cluster_pages_for_defrag(struct inode *inode, 1094 struct page **pages, 1095 unsigned long start_index, 1096 unsigned long num_pages) 1097 { 1098 unsigned long file_end; 1099 u64 isize = i_size_read(inode); 1100 u64 page_start; 1101 u64 page_end; 1102 u64 page_cnt; 1103 int ret; 1104 int i; 1105 int i_done; 1106 struct btrfs_ordered_extent *ordered; 1107 struct extent_state *cached_state = NULL; 1108 struct extent_io_tree *tree; 1109 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 1110 1111 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 1112 if (!isize || start_index > file_end) 1113 return 0; 1114 1115 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); 1116 1117 ret = btrfs_delalloc_reserve_space(inode, 1118 page_cnt << PAGE_CACHE_SHIFT); 1119 if (ret) 1120 return ret; 1121 i_done = 0; 1122 tree = &BTRFS_I(inode)->io_tree; 1123 1124 /* step one, lock all the pages */ 1125 for (i = 0; i < page_cnt; i++) { 1126 struct page *page; 1127 again: 1128 page = find_or_create_page(inode->i_mapping, 1129 start_index + i, mask); 1130 if (!page) 1131 break; 1132 1133 page_start = page_offset(page); 1134 page_end = page_start + PAGE_CACHE_SIZE - 1; 1135 while (1) { 1136 lock_extent_bits(tree, page_start, page_end, 1137 0, &cached_state); 1138 ordered = btrfs_lookup_ordered_extent(inode, 1139 page_start); 1140 unlock_extent_cached(tree, page_start, page_end, 1141 &cached_state, GFP_NOFS); 1142 if (!ordered) 1143 break; 1144 1145 unlock_page(page); 1146 btrfs_start_ordered_extent(inode, ordered, 1); 1147 btrfs_put_ordered_extent(ordered); 1148 lock_page(page); 1149 /* 1150 * we unlocked the page above, so we need check if 1151 * it was released or not. 1152 */ 1153 if (page->mapping != inode->i_mapping) { 1154 unlock_page(page); 1155 page_cache_release(page); 1156 goto again; 1157 } 1158 } 1159 1160 if (!PageUptodate(page)) { 1161 btrfs_readpage(NULL, page); 1162 lock_page(page); 1163 if (!PageUptodate(page)) { 1164 unlock_page(page); 1165 page_cache_release(page); 1166 ret = -EIO; 1167 break; 1168 } 1169 } 1170 1171 if (page->mapping != inode->i_mapping) { 1172 unlock_page(page); 1173 page_cache_release(page); 1174 goto again; 1175 } 1176 1177 pages[i] = page; 1178 i_done++; 1179 } 1180 if (!i_done || ret) 1181 goto out; 1182 1183 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1184 goto out; 1185 1186 /* 1187 * so now we have a nice long stream of locked 1188 * and up to date pages, lets wait on them 1189 */ 1190 for (i = 0; i < i_done; i++) 1191 wait_on_page_writeback(pages[i]); 1192 1193 page_start = page_offset(pages[0]); 1194 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; 1195 1196 lock_extent_bits(&BTRFS_I(inode)->io_tree, 1197 page_start, page_end - 1, 0, &cached_state); 1198 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 1199 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 1200 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, 1201 &cached_state, GFP_NOFS); 1202 1203 if (i_done != page_cnt) { 1204 spin_lock(&BTRFS_I(inode)->lock); 1205 BTRFS_I(inode)->outstanding_extents++; 1206 spin_unlock(&BTRFS_I(inode)->lock); 1207 btrfs_delalloc_release_space(inode, 1208 (page_cnt - i_done) << PAGE_CACHE_SHIFT); 1209 } 1210 1211 1212 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, 1213 &cached_state, GFP_NOFS); 1214 1215 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 1216 page_start, page_end - 1, &cached_state, 1217 GFP_NOFS); 1218 1219 for (i = 0; i < i_done; i++) { 1220 clear_page_dirty_for_io(pages[i]); 1221 ClearPageChecked(pages[i]); 1222 set_page_extent_mapped(pages[i]); 1223 set_page_dirty(pages[i]); 1224 unlock_page(pages[i]); 1225 page_cache_release(pages[i]); 1226 } 1227 return i_done; 1228 out: 1229 for (i = 0; i < i_done; i++) { 1230 unlock_page(pages[i]); 1231 page_cache_release(pages[i]); 1232 } 1233 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT); 1234 return ret; 1235 1236 } 1237 1238 int btrfs_defrag_file(struct inode *inode, struct file *file, 1239 struct btrfs_ioctl_defrag_range_args *range, 1240 u64 newer_than, unsigned long max_to_defrag) 1241 { 1242 struct btrfs_root *root = BTRFS_I(inode)->root; 1243 struct file_ra_state *ra = NULL; 1244 unsigned long last_index; 1245 u64 isize = i_size_read(inode); 1246 u64 last_len = 0; 1247 u64 skip = 0; 1248 u64 defrag_end = 0; 1249 u64 newer_off = range->start; 1250 unsigned long i; 1251 unsigned long ra_index = 0; 1252 int ret; 1253 int defrag_count = 0; 1254 int compress_type = BTRFS_COMPRESS_ZLIB; 1255 u32 extent_thresh = range->extent_thresh; 1256 unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; 1257 unsigned long cluster = max_cluster; 1258 u64 new_align = ~((u64)128 * 1024 - 1); 1259 struct page **pages = NULL; 1260 1261 if (isize == 0) 1262 return 0; 1263 1264 if (range->start >= isize) 1265 return -EINVAL; 1266 1267 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1268 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1269 return -EINVAL; 1270 if (range->compress_type) 1271 compress_type = range->compress_type; 1272 } 1273 1274 if (extent_thresh == 0) 1275 extent_thresh = 256 * 1024; 1276 1277 /* 1278 * if we were not given a file, allocate a readahead 1279 * context 1280 */ 1281 if (!file) { 1282 ra = kzalloc(sizeof(*ra), GFP_NOFS); 1283 if (!ra) 1284 return -ENOMEM; 1285 file_ra_state_init(ra, inode->i_mapping); 1286 } else { 1287 ra = &file->f_ra; 1288 } 1289 1290 pages = kmalloc_array(max_cluster, sizeof(struct page *), 1291 GFP_NOFS); 1292 if (!pages) { 1293 ret = -ENOMEM; 1294 goto out_ra; 1295 } 1296 1297 /* find the last page to defrag */ 1298 if (range->start + range->len > range->start) { 1299 last_index = min_t(u64, isize - 1, 1300 range->start + range->len - 1) >> PAGE_CACHE_SHIFT; 1301 } else { 1302 last_index = (isize - 1) >> PAGE_CACHE_SHIFT; 1303 } 1304 1305 if (newer_than) { 1306 ret = find_new_extents(root, inode, newer_than, 1307 &newer_off, 64 * 1024); 1308 if (!ret) { 1309 range->start = newer_off; 1310 /* 1311 * we always align our defrag to help keep 1312 * the extents in the file evenly spaced 1313 */ 1314 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1315 } else 1316 goto out_ra; 1317 } else { 1318 i = range->start >> PAGE_CACHE_SHIFT; 1319 } 1320 if (!max_to_defrag) 1321 max_to_defrag = last_index - i + 1; 1322 1323 /* 1324 * make writeback starts from i, so the defrag range can be 1325 * written sequentially. 1326 */ 1327 if (i < inode->i_mapping->writeback_index) 1328 inode->i_mapping->writeback_index = i; 1329 1330 while (i <= last_index && defrag_count < max_to_defrag && 1331 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) { 1332 /* 1333 * make sure we stop running if someone unmounts 1334 * the FS 1335 */ 1336 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1337 break; 1338 1339 if (btrfs_defrag_cancelled(root->fs_info)) { 1340 printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n"); 1341 ret = -EAGAIN; 1342 break; 1343 } 1344 1345 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, 1346 extent_thresh, &last_len, &skip, 1347 &defrag_end, range->flags & 1348 BTRFS_DEFRAG_RANGE_COMPRESS)) { 1349 unsigned long next; 1350 /* 1351 * the should_defrag function tells us how much to skip 1352 * bump our counter by the suggested amount 1353 */ 1354 next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE); 1355 i = max(i + 1, next); 1356 continue; 1357 } 1358 1359 if (!newer_than) { 1360 cluster = (PAGE_CACHE_ALIGN(defrag_end) >> 1361 PAGE_CACHE_SHIFT) - i; 1362 cluster = min(cluster, max_cluster); 1363 } else { 1364 cluster = max_cluster; 1365 } 1366 1367 if (i + cluster > ra_index) { 1368 ra_index = max(i, ra_index); 1369 btrfs_force_ra(inode->i_mapping, ra, file, ra_index, 1370 cluster); 1371 ra_index += cluster; 1372 } 1373 1374 mutex_lock(&inode->i_mutex); 1375 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) 1376 BTRFS_I(inode)->force_compress = compress_type; 1377 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1378 if (ret < 0) { 1379 mutex_unlock(&inode->i_mutex); 1380 goto out_ra; 1381 } 1382 1383 defrag_count += ret; 1384 balance_dirty_pages_ratelimited(inode->i_mapping); 1385 mutex_unlock(&inode->i_mutex); 1386 1387 if (newer_than) { 1388 if (newer_off == (u64)-1) 1389 break; 1390 1391 if (ret > 0) 1392 i += ret; 1393 1394 newer_off = max(newer_off + 1, 1395 (u64)i << PAGE_CACHE_SHIFT); 1396 1397 ret = find_new_extents(root, inode, 1398 newer_than, &newer_off, 1399 64 * 1024); 1400 if (!ret) { 1401 range->start = newer_off; 1402 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1403 } else { 1404 break; 1405 } 1406 } else { 1407 if (ret > 0) { 1408 i += ret; 1409 last_len += ret << PAGE_CACHE_SHIFT; 1410 } else { 1411 i++; 1412 last_len = 0; 1413 } 1414 } 1415 } 1416 1417 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) { 1418 filemap_flush(inode->i_mapping); 1419 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 1420 &BTRFS_I(inode)->runtime_flags)) 1421 filemap_flush(inode->i_mapping); 1422 } 1423 1424 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 1425 /* the filemap_flush will queue IO into the worker threads, but 1426 * we have to make sure the IO is actually started and that 1427 * ordered extents get created before we return 1428 */ 1429 atomic_inc(&root->fs_info->async_submit_draining); 1430 while (atomic_read(&root->fs_info->nr_async_submits) || 1431 atomic_read(&root->fs_info->async_delalloc_pages)) { 1432 wait_event(root->fs_info->async_submit_wait, 1433 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 1434 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 1435 } 1436 atomic_dec(&root->fs_info->async_submit_draining); 1437 } 1438 1439 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1440 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO); 1441 } 1442 1443 ret = defrag_count; 1444 1445 out_ra: 1446 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1447 mutex_lock(&inode->i_mutex); 1448 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; 1449 mutex_unlock(&inode->i_mutex); 1450 } 1451 if (!file) 1452 kfree(ra); 1453 kfree(pages); 1454 return ret; 1455 } 1456 1457 static noinline int btrfs_ioctl_resize(struct file *file, 1458 void __user *arg) 1459 { 1460 u64 new_size; 1461 u64 old_size; 1462 u64 devid = 1; 1463 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 1464 struct btrfs_ioctl_vol_args *vol_args; 1465 struct btrfs_trans_handle *trans; 1466 struct btrfs_device *device = NULL; 1467 char *sizestr; 1468 char *retptr; 1469 char *devstr = NULL; 1470 int ret = 0; 1471 int mod = 0; 1472 1473 if (!capable(CAP_SYS_ADMIN)) 1474 return -EPERM; 1475 1476 ret = mnt_want_write_file(file); 1477 if (ret) 1478 return ret; 1479 1480 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1481 1)) { 1482 mnt_drop_write_file(file); 1483 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 1484 } 1485 1486 mutex_lock(&root->fs_info->volume_mutex); 1487 vol_args = memdup_user(arg, sizeof(*vol_args)); 1488 if (IS_ERR(vol_args)) { 1489 ret = PTR_ERR(vol_args); 1490 goto out; 1491 } 1492 1493 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1494 1495 sizestr = vol_args->name; 1496 devstr = strchr(sizestr, ':'); 1497 if (devstr) { 1498 sizestr = devstr + 1; 1499 *devstr = '\0'; 1500 devstr = vol_args->name; 1501 ret = kstrtoull(devstr, 10, &devid); 1502 if (ret) 1503 goto out_free; 1504 if (!devid) { 1505 ret = -EINVAL; 1506 goto out_free; 1507 } 1508 btrfs_info(root->fs_info, "resizing devid %llu", devid); 1509 } 1510 1511 device = btrfs_find_device(root->fs_info, devid, NULL, NULL); 1512 if (!device) { 1513 btrfs_info(root->fs_info, "resizer unable to find device %llu", 1514 devid); 1515 ret = -ENODEV; 1516 goto out_free; 1517 } 1518 1519 if (!device->writeable) { 1520 btrfs_info(root->fs_info, 1521 "resizer unable to apply on readonly device %llu", 1522 devid); 1523 ret = -EPERM; 1524 goto out_free; 1525 } 1526 1527 if (!strcmp(sizestr, "max")) 1528 new_size = device->bdev->bd_inode->i_size; 1529 else { 1530 if (sizestr[0] == '-') { 1531 mod = -1; 1532 sizestr++; 1533 } else if (sizestr[0] == '+') { 1534 mod = 1; 1535 sizestr++; 1536 } 1537 new_size = memparse(sizestr, &retptr); 1538 if (*retptr != '\0' || new_size == 0) { 1539 ret = -EINVAL; 1540 goto out_free; 1541 } 1542 } 1543 1544 if (device->is_tgtdev_for_dev_replace) { 1545 ret = -EPERM; 1546 goto out_free; 1547 } 1548 1549 old_size = btrfs_device_get_total_bytes(device); 1550 1551 if (mod < 0) { 1552 if (new_size > old_size) { 1553 ret = -EINVAL; 1554 goto out_free; 1555 } 1556 new_size = old_size - new_size; 1557 } else if (mod > 0) { 1558 if (new_size > ULLONG_MAX - old_size) { 1559 ret = -ERANGE; 1560 goto out_free; 1561 } 1562 new_size = old_size + new_size; 1563 } 1564 1565 if (new_size < 256 * 1024 * 1024) { 1566 ret = -EINVAL; 1567 goto out_free; 1568 } 1569 if (new_size > device->bdev->bd_inode->i_size) { 1570 ret = -EFBIG; 1571 goto out_free; 1572 } 1573 1574 new_size = div_u64(new_size, root->sectorsize); 1575 new_size *= root->sectorsize; 1576 1577 printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n", 1578 rcu_str_deref(device->name), new_size); 1579 1580 if (new_size > old_size) { 1581 trans = btrfs_start_transaction(root, 0); 1582 if (IS_ERR(trans)) { 1583 ret = PTR_ERR(trans); 1584 goto out_free; 1585 } 1586 ret = btrfs_grow_device(trans, device, new_size); 1587 btrfs_commit_transaction(trans, root); 1588 } else if (new_size < old_size) { 1589 ret = btrfs_shrink_device(device, new_size); 1590 } /* equal, nothing need to do */ 1591 1592 out_free: 1593 kfree(vol_args); 1594 out: 1595 mutex_unlock(&root->fs_info->volume_mutex); 1596 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 1597 mnt_drop_write_file(file); 1598 return ret; 1599 } 1600 1601 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1602 char *name, unsigned long fd, int subvol, 1603 u64 *transid, bool readonly, 1604 struct btrfs_qgroup_inherit *inherit) 1605 { 1606 int namelen; 1607 int ret = 0; 1608 1609 ret = mnt_want_write_file(file); 1610 if (ret) 1611 goto out; 1612 1613 namelen = strlen(name); 1614 if (strchr(name, '/')) { 1615 ret = -EINVAL; 1616 goto out_drop_write; 1617 } 1618 1619 if (name[0] == '.' && 1620 (namelen == 1 || (name[1] == '.' && namelen == 2))) { 1621 ret = -EEXIST; 1622 goto out_drop_write; 1623 } 1624 1625 if (subvol) { 1626 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1627 NULL, transid, readonly, inherit); 1628 } else { 1629 struct fd src = fdget(fd); 1630 struct inode *src_inode; 1631 if (!src.file) { 1632 ret = -EINVAL; 1633 goto out_drop_write; 1634 } 1635 1636 src_inode = file_inode(src.file); 1637 if (src_inode->i_sb != file_inode(file)->i_sb) { 1638 btrfs_info(BTRFS_I(src_inode)->root->fs_info, 1639 "Snapshot src from another FS"); 1640 ret = -EXDEV; 1641 } else if (!inode_owner_or_capable(src_inode)) { 1642 /* 1643 * Subvolume creation is not restricted, but snapshots 1644 * are limited to own subvolumes only 1645 */ 1646 ret = -EPERM; 1647 } else { 1648 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1649 BTRFS_I(src_inode)->root, 1650 transid, readonly, inherit); 1651 } 1652 fdput(src); 1653 } 1654 out_drop_write: 1655 mnt_drop_write_file(file); 1656 out: 1657 return ret; 1658 } 1659 1660 static noinline int btrfs_ioctl_snap_create(struct file *file, 1661 void __user *arg, int subvol) 1662 { 1663 struct btrfs_ioctl_vol_args *vol_args; 1664 int ret; 1665 1666 vol_args = memdup_user(arg, sizeof(*vol_args)); 1667 if (IS_ERR(vol_args)) 1668 return PTR_ERR(vol_args); 1669 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1670 1671 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1672 vol_args->fd, subvol, 1673 NULL, false, NULL); 1674 1675 kfree(vol_args); 1676 return ret; 1677 } 1678 1679 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1680 void __user *arg, int subvol) 1681 { 1682 struct btrfs_ioctl_vol_args_v2 *vol_args; 1683 int ret; 1684 u64 transid = 0; 1685 u64 *ptr = NULL; 1686 bool readonly = false; 1687 struct btrfs_qgroup_inherit *inherit = NULL; 1688 1689 vol_args = memdup_user(arg, sizeof(*vol_args)); 1690 if (IS_ERR(vol_args)) 1691 return PTR_ERR(vol_args); 1692 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1693 1694 if (vol_args->flags & 1695 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | 1696 BTRFS_SUBVOL_QGROUP_INHERIT)) { 1697 ret = -EOPNOTSUPP; 1698 goto free_args; 1699 } 1700 1701 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1702 ptr = &transid; 1703 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1704 readonly = true; 1705 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { 1706 if (vol_args->size > PAGE_CACHE_SIZE) { 1707 ret = -EINVAL; 1708 goto free_args; 1709 } 1710 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); 1711 if (IS_ERR(inherit)) { 1712 ret = PTR_ERR(inherit); 1713 goto free_args; 1714 } 1715 } 1716 1717 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1718 vol_args->fd, subvol, ptr, 1719 readonly, inherit); 1720 if (ret) 1721 goto free_inherit; 1722 1723 if (ptr && copy_to_user(arg + 1724 offsetof(struct btrfs_ioctl_vol_args_v2, 1725 transid), 1726 ptr, sizeof(*ptr))) 1727 ret = -EFAULT; 1728 1729 free_inherit: 1730 kfree(inherit); 1731 free_args: 1732 kfree(vol_args); 1733 return ret; 1734 } 1735 1736 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1737 void __user *arg) 1738 { 1739 struct inode *inode = file_inode(file); 1740 struct btrfs_root *root = BTRFS_I(inode)->root; 1741 int ret = 0; 1742 u64 flags = 0; 1743 1744 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1745 return -EINVAL; 1746 1747 down_read(&root->fs_info->subvol_sem); 1748 if (btrfs_root_readonly(root)) 1749 flags |= BTRFS_SUBVOL_RDONLY; 1750 up_read(&root->fs_info->subvol_sem); 1751 1752 if (copy_to_user(arg, &flags, sizeof(flags))) 1753 ret = -EFAULT; 1754 1755 return ret; 1756 } 1757 1758 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1759 void __user *arg) 1760 { 1761 struct inode *inode = file_inode(file); 1762 struct btrfs_root *root = BTRFS_I(inode)->root; 1763 struct btrfs_trans_handle *trans; 1764 u64 root_flags; 1765 u64 flags; 1766 int ret = 0; 1767 1768 if (!inode_owner_or_capable(inode)) 1769 return -EPERM; 1770 1771 ret = mnt_want_write_file(file); 1772 if (ret) 1773 goto out; 1774 1775 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 1776 ret = -EINVAL; 1777 goto out_drop_write; 1778 } 1779 1780 if (copy_from_user(&flags, arg, sizeof(flags))) { 1781 ret = -EFAULT; 1782 goto out_drop_write; 1783 } 1784 1785 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) { 1786 ret = -EINVAL; 1787 goto out_drop_write; 1788 } 1789 1790 if (flags & ~BTRFS_SUBVOL_RDONLY) { 1791 ret = -EOPNOTSUPP; 1792 goto out_drop_write; 1793 } 1794 1795 down_write(&root->fs_info->subvol_sem); 1796 1797 /* nothing to do */ 1798 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1799 goto out_drop_sem; 1800 1801 root_flags = btrfs_root_flags(&root->root_item); 1802 if (flags & BTRFS_SUBVOL_RDONLY) { 1803 btrfs_set_root_flags(&root->root_item, 1804 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1805 } else { 1806 /* 1807 * Block RO -> RW transition if this subvolume is involved in 1808 * send 1809 */ 1810 spin_lock(&root->root_item_lock); 1811 if (root->send_in_progress == 0) { 1812 btrfs_set_root_flags(&root->root_item, 1813 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1814 spin_unlock(&root->root_item_lock); 1815 } else { 1816 spin_unlock(&root->root_item_lock); 1817 btrfs_warn(root->fs_info, 1818 "Attempt to set subvolume %llu read-write during send", 1819 root->root_key.objectid); 1820 ret = -EPERM; 1821 goto out_drop_sem; 1822 } 1823 } 1824 1825 trans = btrfs_start_transaction(root, 1); 1826 if (IS_ERR(trans)) { 1827 ret = PTR_ERR(trans); 1828 goto out_reset; 1829 } 1830 1831 ret = btrfs_update_root(trans, root->fs_info->tree_root, 1832 &root->root_key, &root->root_item); 1833 1834 btrfs_commit_transaction(trans, root); 1835 out_reset: 1836 if (ret) 1837 btrfs_set_root_flags(&root->root_item, root_flags); 1838 out_drop_sem: 1839 up_write(&root->fs_info->subvol_sem); 1840 out_drop_write: 1841 mnt_drop_write_file(file); 1842 out: 1843 return ret; 1844 } 1845 1846 /* 1847 * helper to check if the subvolume references other subvolumes 1848 */ 1849 static noinline int may_destroy_subvol(struct btrfs_root *root) 1850 { 1851 struct btrfs_path *path; 1852 struct btrfs_dir_item *di; 1853 struct btrfs_key key; 1854 u64 dir_id; 1855 int ret; 1856 1857 path = btrfs_alloc_path(); 1858 if (!path) 1859 return -ENOMEM; 1860 1861 /* Make sure this root isn't set as the default subvol */ 1862 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 1863 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path, 1864 dir_id, "default", 7, 0); 1865 if (di && !IS_ERR(di)) { 1866 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key); 1867 if (key.objectid == root->root_key.objectid) { 1868 ret = -EPERM; 1869 btrfs_err(root->fs_info, "deleting default subvolume " 1870 "%llu is not allowed", key.objectid); 1871 goto out; 1872 } 1873 btrfs_release_path(path); 1874 } 1875 1876 key.objectid = root->root_key.objectid; 1877 key.type = BTRFS_ROOT_REF_KEY; 1878 key.offset = (u64)-1; 1879 1880 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, 1881 &key, path, 0, 0); 1882 if (ret < 0) 1883 goto out; 1884 BUG_ON(ret == 0); 1885 1886 ret = 0; 1887 if (path->slots[0] > 0) { 1888 path->slots[0]--; 1889 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 1890 if (key.objectid == root->root_key.objectid && 1891 key.type == BTRFS_ROOT_REF_KEY) 1892 ret = -ENOTEMPTY; 1893 } 1894 out: 1895 btrfs_free_path(path); 1896 return ret; 1897 } 1898 1899 static noinline int key_in_sk(struct btrfs_key *key, 1900 struct btrfs_ioctl_search_key *sk) 1901 { 1902 struct btrfs_key test; 1903 int ret; 1904 1905 test.objectid = sk->min_objectid; 1906 test.type = sk->min_type; 1907 test.offset = sk->min_offset; 1908 1909 ret = btrfs_comp_cpu_keys(key, &test); 1910 if (ret < 0) 1911 return 0; 1912 1913 test.objectid = sk->max_objectid; 1914 test.type = sk->max_type; 1915 test.offset = sk->max_offset; 1916 1917 ret = btrfs_comp_cpu_keys(key, &test); 1918 if (ret > 0) 1919 return 0; 1920 return 1; 1921 } 1922 1923 static noinline int copy_to_sk(struct btrfs_root *root, 1924 struct btrfs_path *path, 1925 struct btrfs_key *key, 1926 struct btrfs_ioctl_search_key *sk, 1927 size_t *buf_size, 1928 char __user *ubuf, 1929 unsigned long *sk_offset, 1930 int *num_found) 1931 { 1932 u64 found_transid; 1933 struct extent_buffer *leaf; 1934 struct btrfs_ioctl_search_header sh; 1935 unsigned long item_off; 1936 unsigned long item_len; 1937 int nritems; 1938 int i; 1939 int slot; 1940 int ret = 0; 1941 1942 leaf = path->nodes[0]; 1943 slot = path->slots[0]; 1944 nritems = btrfs_header_nritems(leaf); 1945 1946 if (btrfs_header_generation(leaf) > sk->max_transid) { 1947 i = nritems; 1948 goto advance_key; 1949 } 1950 found_transid = btrfs_header_generation(leaf); 1951 1952 for (i = slot; i < nritems; i++) { 1953 item_off = btrfs_item_ptr_offset(leaf, i); 1954 item_len = btrfs_item_size_nr(leaf, i); 1955 1956 btrfs_item_key_to_cpu(leaf, key, i); 1957 if (!key_in_sk(key, sk)) 1958 continue; 1959 1960 if (sizeof(sh) + item_len > *buf_size) { 1961 if (*num_found) { 1962 ret = 1; 1963 goto out; 1964 } 1965 1966 /* 1967 * return one empty item back for v1, which does not 1968 * handle -EOVERFLOW 1969 */ 1970 1971 *buf_size = sizeof(sh) + item_len; 1972 item_len = 0; 1973 ret = -EOVERFLOW; 1974 } 1975 1976 if (sizeof(sh) + item_len + *sk_offset > *buf_size) { 1977 ret = 1; 1978 goto out; 1979 } 1980 1981 sh.objectid = key->objectid; 1982 sh.offset = key->offset; 1983 sh.type = key->type; 1984 sh.len = item_len; 1985 sh.transid = found_transid; 1986 1987 /* copy search result header */ 1988 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) { 1989 ret = -EFAULT; 1990 goto out; 1991 } 1992 1993 *sk_offset += sizeof(sh); 1994 1995 if (item_len) { 1996 char __user *up = ubuf + *sk_offset; 1997 /* copy the item */ 1998 if (read_extent_buffer_to_user(leaf, up, 1999 item_off, item_len)) { 2000 ret = -EFAULT; 2001 goto out; 2002 } 2003 2004 *sk_offset += item_len; 2005 } 2006 (*num_found)++; 2007 2008 if (ret) /* -EOVERFLOW from above */ 2009 goto out; 2010 2011 if (*num_found >= sk->nr_items) { 2012 ret = 1; 2013 goto out; 2014 } 2015 } 2016 advance_key: 2017 ret = 0; 2018 if (key->offset < (u64)-1 && key->offset < sk->max_offset) 2019 key->offset++; 2020 else if (key->type < (u8)-1 && key->type < sk->max_type) { 2021 key->offset = 0; 2022 key->type++; 2023 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { 2024 key->offset = 0; 2025 key->type = 0; 2026 key->objectid++; 2027 } else 2028 ret = 1; 2029 out: 2030 /* 2031 * 0: all items from this leaf copied, continue with next 2032 * 1: * more items can be copied, but unused buffer is too small 2033 * * all items were found 2034 * Either way, it will stops the loop which iterates to the next 2035 * leaf 2036 * -EOVERFLOW: item was to large for buffer 2037 * -EFAULT: could not copy extent buffer back to userspace 2038 */ 2039 return ret; 2040 } 2041 2042 static noinline int search_ioctl(struct inode *inode, 2043 struct btrfs_ioctl_search_key *sk, 2044 size_t *buf_size, 2045 char __user *ubuf) 2046 { 2047 struct btrfs_root *root; 2048 struct btrfs_key key; 2049 struct btrfs_path *path; 2050 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; 2051 int ret; 2052 int num_found = 0; 2053 unsigned long sk_offset = 0; 2054 2055 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) { 2056 *buf_size = sizeof(struct btrfs_ioctl_search_header); 2057 return -EOVERFLOW; 2058 } 2059 2060 path = btrfs_alloc_path(); 2061 if (!path) 2062 return -ENOMEM; 2063 2064 if (sk->tree_id == 0) { 2065 /* search the root of the inode that was passed */ 2066 root = BTRFS_I(inode)->root; 2067 } else { 2068 key.objectid = sk->tree_id; 2069 key.type = BTRFS_ROOT_ITEM_KEY; 2070 key.offset = (u64)-1; 2071 root = btrfs_read_fs_root_no_name(info, &key); 2072 if (IS_ERR(root)) { 2073 printk(KERN_ERR "BTRFS: could not find root %llu\n", 2074 sk->tree_id); 2075 btrfs_free_path(path); 2076 return -ENOENT; 2077 } 2078 } 2079 2080 key.objectid = sk->min_objectid; 2081 key.type = sk->min_type; 2082 key.offset = sk->min_offset; 2083 2084 while (1) { 2085 ret = btrfs_search_forward(root, &key, path, sk->min_transid); 2086 if (ret != 0) { 2087 if (ret > 0) 2088 ret = 0; 2089 goto err; 2090 } 2091 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf, 2092 &sk_offset, &num_found); 2093 btrfs_release_path(path); 2094 if (ret) 2095 break; 2096 2097 } 2098 if (ret > 0) 2099 ret = 0; 2100 err: 2101 sk->nr_items = num_found; 2102 btrfs_free_path(path); 2103 return ret; 2104 } 2105 2106 static noinline int btrfs_ioctl_tree_search(struct file *file, 2107 void __user *argp) 2108 { 2109 struct btrfs_ioctl_search_args __user *uargs; 2110 struct btrfs_ioctl_search_key sk; 2111 struct inode *inode; 2112 int ret; 2113 size_t buf_size; 2114 2115 if (!capable(CAP_SYS_ADMIN)) 2116 return -EPERM; 2117 2118 uargs = (struct btrfs_ioctl_search_args __user *)argp; 2119 2120 if (copy_from_user(&sk, &uargs->key, sizeof(sk))) 2121 return -EFAULT; 2122 2123 buf_size = sizeof(uargs->buf); 2124 2125 inode = file_inode(file); 2126 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf); 2127 2128 /* 2129 * In the origin implementation an overflow is handled by returning a 2130 * search header with a len of zero, so reset ret. 2131 */ 2132 if (ret == -EOVERFLOW) 2133 ret = 0; 2134 2135 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk))) 2136 ret = -EFAULT; 2137 return ret; 2138 } 2139 2140 static noinline int btrfs_ioctl_tree_search_v2(struct file *file, 2141 void __user *argp) 2142 { 2143 struct btrfs_ioctl_search_args_v2 __user *uarg; 2144 struct btrfs_ioctl_search_args_v2 args; 2145 struct inode *inode; 2146 int ret; 2147 size_t buf_size; 2148 const size_t buf_limit = 16 * 1024 * 1024; 2149 2150 if (!capable(CAP_SYS_ADMIN)) 2151 return -EPERM; 2152 2153 /* copy search header and buffer size */ 2154 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp; 2155 if (copy_from_user(&args, uarg, sizeof(args))) 2156 return -EFAULT; 2157 2158 buf_size = args.buf_size; 2159 2160 if (buf_size < sizeof(struct btrfs_ioctl_search_header)) 2161 return -EOVERFLOW; 2162 2163 /* limit result size to 16MB */ 2164 if (buf_size > buf_limit) 2165 buf_size = buf_limit; 2166 2167 inode = file_inode(file); 2168 ret = search_ioctl(inode, &args.key, &buf_size, 2169 (char *)(&uarg->buf[0])); 2170 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key))) 2171 ret = -EFAULT; 2172 else if (ret == -EOVERFLOW && 2173 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size))) 2174 ret = -EFAULT; 2175 2176 return ret; 2177 } 2178 2179 /* 2180 * Search INODE_REFs to identify path name of 'dirid' directory 2181 * in a 'tree_id' tree. and sets path name to 'name'. 2182 */ 2183 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 2184 u64 tree_id, u64 dirid, char *name) 2185 { 2186 struct btrfs_root *root; 2187 struct btrfs_key key; 2188 char *ptr; 2189 int ret = -1; 2190 int slot; 2191 int len; 2192 int total_len = 0; 2193 struct btrfs_inode_ref *iref; 2194 struct extent_buffer *l; 2195 struct btrfs_path *path; 2196 2197 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 2198 name[0]='\0'; 2199 return 0; 2200 } 2201 2202 path = btrfs_alloc_path(); 2203 if (!path) 2204 return -ENOMEM; 2205 2206 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; 2207 2208 key.objectid = tree_id; 2209 key.type = BTRFS_ROOT_ITEM_KEY; 2210 key.offset = (u64)-1; 2211 root = btrfs_read_fs_root_no_name(info, &key); 2212 if (IS_ERR(root)) { 2213 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id); 2214 ret = -ENOENT; 2215 goto out; 2216 } 2217 2218 key.objectid = dirid; 2219 key.type = BTRFS_INODE_REF_KEY; 2220 key.offset = (u64)-1; 2221 2222 while (1) { 2223 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2224 if (ret < 0) 2225 goto out; 2226 else if (ret > 0) { 2227 ret = btrfs_previous_item(root, path, dirid, 2228 BTRFS_INODE_REF_KEY); 2229 if (ret < 0) 2230 goto out; 2231 else if (ret > 0) { 2232 ret = -ENOENT; 2233 goto out; 2234 } 2235 } 2236 2237 l = path->nodes[0]; 2238 slot = path->slots[0]; 2239 btrfs_item_key_to_cpu(l, &key, slot); 2240 2241 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 2242 len = btrfs_inode_ref_name_len(l, iref); 2243 ptr -= len + 1; 2244 total_len += len + 1; 2245 if (ptr < name) { 2246 ret = -ENAMETOOLONG; 2247 goto out; 2248 } 2249 2250 *(ptr + len) = '/'; 2251 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len); 2252 2253 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 2254 break; 2255 2256 btrfs_release_path(path); 2257 key.objectid = key.offset; 2258 key.offset = (u64)-1; 2259 dirid = key.objectid; 2260 } 2261 memmove(name, ptr, total_len); 2262 name[total_len] = '\0'; 2263 ret = 0; 2264 out: 2265 btrfs_free_path(path); 2266 return ret; 2267 } 2268 2269 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 2270 void __user *argp) 2271 { 2272 struct btrfs_ioctl_ino_lookup_args *args; 2273 struct inode *inode; 2274 int ret = 0; 2275 2276 args = memdup_user(argp, sizeof(*args)); 2277 if (IS_ERR(args)) 2278 return PTR_ERR(args); 2279 2280 inode = file_inode(file); 2281 2282 /* 2283 * Unprivileged query to obtain the containing subvolume root id. The 2284 * path is reset so it's consistent with btrfs_search_path_in_tree. 2285 */ 2286 if (args->treeid == 0) 2287 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 2288 2289 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) { 2290 args->name[0] = 0; 2291 goto out; 2292 } 2293 2294 if (!capable(CAP_SYS_ADMIN)) { 2295 ret = -EPERM; 2296 goto out; 2297 } 2298 2299 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 2300 args->treeid, args->objectid, 2301 args->name); 2302 2303 out: 2304 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 2305 ret = -EFAULT; 2306 2307 kfree(args); 2308 return ret; 2309 } 2310 2311 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 2312 void __user *arg) 2313 { 2314 struct dentry *parent = file->f_path.dentry; 2315 struct dentry *dentry; 2316 struct inode *dir = d_inode(parent); 2317 struct inode *inode; 2318 struct btrfs_root *root = BTRFS_I(dir)->root; 2319 struct btrfs_root *dest = NULL; 2320 struct btrfs_ioctl_vol_args *vol_args; 2321 struct btrfs_trans_handle *trans; 2322 struct btrfs_block_rsv block_rsv; 2323 u64 root_flags; 2324 u64 qgroup_reserved; 2325 int namelen; 2326 int ret; 2327 int err = 0; 2328 2329 vol_args = memdup_user(arg, sizeof(*vol_args)); 2330 if (IS_ERR(vol_args)) 2331 return PTR_ERR(vol_args); 2332 2333 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2334 namelen = strlen(vol_args->name); 2335 if (strchr(vol_args->name, '/') || 2336 strncmp(vol_args->name, "..", namelen) == 0) { 2337 err = -EINVAL; 2338 goto out; 2339 } 2340 2341 err = mnt_want_write_file(file); 2342 if (err) 2343 goto out; 2344 2345 2346 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT); 2347 if (err == -EINTR) 2348 goto out_drop_write; 2349 dentry = lookup_one_len(vol_args->name, parent, namelen); 2350 if (IS_ERR(dentry)) { 2351 err = PTR_ERR(dentry); 2352 goto out_unlock_dir; 2353 } 2354 2355 if (d_really_is_negative(dentry)) { 2356 err = -ENOENT; 2357 goto out_dput; 2358 } 2359 2360 inode = d_inode(dentry); 2361 dest = BTRFS_I(inode)->root; 2362 if (!capable(CAP_SYS_ADMIN)) { 2363 /* 2364 * Regular user. Only allow this with a special mount 2365 * option, when the user has write+exec access to the 2366 * subvol root, and when rmdir(2) would have been 2367 * allowed. 2368 * 2369 * Note that this is _not_ check that the subvol is 2370 * empty or doesn't contain data that we wouldn't 2371 * otherwise be able to delete. 2372 * 2373 * Users who want to delete empty subvols should try 2374 * rmdir(2). 2375 */ 2376 err = -EPERM; 2377 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 2378 goto out_dput; 2379 2380 /* 2381 * Do not allow deletion if the parent dir is the same 2382 * as the dir to be deleted. That means the ioctl 2383 * must be called on the dentry referencing the root 2384 * of the subvol, not a random directory contained 2385 * within it. 2386 */ 2387 err = -EINVAL; 2388 if (root == dest) 2389 goto out_dput; 2390 2391 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 2392 if (err) 2393 goto out_dput; 2394 } 2395 2396 /* check if subvolume may be deleted by a user */ 2397 err = btrfs_may_delete(dir, dentry, 1); 2398 if (err) 2399 goto out_dput; 2400 2401 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 2402 err = -EINVAL; 2403 goto out_dput; 2404 } 2405 2406 mutex_lock(&inode->i_mutex); 2407 2408 /* 2409 * Don't allow to delete a subvolume with send in progress. This is 2410 * inside the i_mutex so the error handling that has to drop the bit 2411 * again is not run concurrently. 2412 */ 2413 spin_lock(&dest->root_item_lock); 2414 root_flags = btrfs_root_flags(&dest->root_item); 2415 if (dest->send_in_progress == 0) { 2416 btrfs_set_root_flags(&dest->root_item, 2417 root_flags | BTRFS_ROOT_SUBVOL_DEAD); 2418 spin_unlock(&dest->root_item_lock); 2419 } else { 2420 spin_unlock(&dest->root_item_lock); 2421 btrfs_warn(root->fs_info, 2422 "Attempt to delete subvolume %llu during send", 2423 dest->root_key.objectid); 2424 err = -EPERM; 2425 goto out_unlock_inode; 2426 } 2427 2428 down_write(&root->fs_info->subvol_sem); 2429 2430 err = may_destroy_subvol(dest); 2431 if (err) 2432 goto out_up_write; 2433 2434 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); 2435 /* 2436 * One for dir inode, two for dir entries, two for root 2437 * ref/backref. 2438 */ 2439 err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 2440 5, &qgroup_reserved, true); 2441 if (err) 2442 goto out_up_write; 2443 2444 trans = btrfs_start_transaction(root, 0); 2445 if (IS_ERR(trans)) { 2446 err = PTR_ERR(trans); 2447 goto out_release; 2448 } 2449 trans->block_rsv = &block_rsv; 2450 trans->bytes_reserved = block_rsv.size; 2451 2452 ret = btrfs_unlink_subvol(trans, root, dir, 2453 dest->root_key.objectid, 2454 dentry->d_name.name, 2455 dentry->d_name.len); 2456 if (ret) { 2457 err = ret; 2458 btrfs_abort_transaction(trans, root, ret); 2459 goto out_end_trans; 2460 } 2461 2462 btrfs_record_root_in_trans(trans, dest); 2463 2464 memset(&dest->root_item.drop_progress, 0, 2465 sizeof(dest->root_item.drop_progress)); 2466 dest->root_item.drop_level = 0; 2467 btrfs_set_root_refs(&dest->root_item, 0); 2468 2469 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) { 2470 ret = btrfs_insert_orphan_item(trans, 2471 root->fs_info->tree_root, 2472 dest->root_key.objectid); 2473 if (ret) { 2474 btrfs_abort_transaction(trans, root, ret); 2475 err = ret; 2476 goto out_end_trans; 2477 } 2478 } 2479 2480 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, 2481 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL, 2482 dest->root_key.objectid); 2483 if (ret && ret != -ENOENT) { 2484 btrfs_abort_transaction(trans, root, ret); 2485 err = ret; 2486 goto out_end_trans; 2487 } 2488 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) { 2489 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, 2490 dest->root_item.received_uuid, 2491 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 2492 dest->root_key.objectid); 2493 if (ret && ret != -ENOENT) { 2494 btrfs_abort_transaction(trans, root, ret); 2495 err = ret; 2496 goto out_end_trans; 2497 } 2498 } 2499 2500 out_end_trans: 2501 trans->block_rsv = NULL; 2502 trans->bytes_reserved = 0; 2503 ret = btrfs_end_transaction(trans, root); 2504 if (ret && !err) 2505 err = ret; 2506 inode->i_flags |= S_DEAD; 2507 out_release: 2508 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); 2509 out_up_write: 2510 up_write(&root->fs_info->subvol_sem); 2511 if (err) { 2512 spin_lock(&dest->root_item_lock); 2513 root_flags = btrfs_root_flags(&dest->root_item); 2514 btrfs_set_root_flags(&dest->root_item, 2515 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD); 2516 spin_unlock(&dest->root_item_lock); 2517 } 2518 out_unlock_inode: 2519 mutex_unlock(&inode->i_mutex); 2520 if (!err) { 2521 d_invalidate(dentry); 2522 btrfs_invalidate_inodes(dest); 2523 d_delete(dentry); 2524 ASSERT(dest->send_in_progress == 0); 2525 2526 /* the last ref */ 2527 if (dest->ino_cache_inode) { 2528 iput(dest->ino_cache_inode); 2529 dest->ino_cache_inode = NULL; 2530 } 2531 } 2532 out_dput: 2533 dput(dentry); 2534 out_unlock_dir: 2535 mutex_unlock(&dir->i_mutex); 2536 out_drop_write: 2537 mnt_drop_write_file(file); 2538 out: 2539 kfree(vol_args); 2540 return err; 2541 } 2542 2543 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 2544 { 2545 struct inode *inode = file_inode(file); 2546 struct btrfs_root *root = BTRFS_I(inode)->root; 2547 struct btrfs_ioctl_defrag_range_args *range; 2548 int ret; 2549 2550 ret = mnt_want_write_file(file); 2551 if (ret) 2552 return ret; 2553 2554 if (btrfs_root_readonly(root)) { 2555 ret = -EROFS; 2556 goto out; 2557 } 2558 2559 switch (inode->i_mode & S_IFMT) { 2560 case S_IFDIR: 2561 if (!capable(CAP_SYS_ADMIN)) { 2562 ret = -EPERM; 2563 goto out; 2564 } 2565 ret = btrfs_defrag_root(root); 2566 if (ret) 2567 goto out; 2568 ret = btrfs_defrag_root(root->fs_info->extent_root); 2569 break; 2570 case S_IFREG: 2571 if (!(file->f_mode & FMODE_WRITE)) { 2572 ret = -EINVAL; 2573 goto out; 2574 } 2575 2576 range = kzalloc(sizeof(*range), GFP_KERNEL); 2577 if (!range) { 2578 ret = -ENOMEM; 2579 goto out; 2580 } 2581 2582 if (argp) { 2583 if (copy_from_user(range, argp, 2584 sizeof(*range))) { 2585 ret = -EFAULT; 2586 kfree(range); 2587 goto out; 2588 } 2589 /* compression requires us to start the IO */ 2590 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2591 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2592 range->extent_thresh = (u32)-1; 2593 } 2594 } else { 2595 /* the rest are all set to zero by kzalloc */ 2596 range->len = (u64)-1; 2597 } 2598 ret = btrfs_defrag_file(file_inode(file), file, 2599 range, 0, 0); 2600 if (ret > 0) 2601 ret = 0; 2602 kfree(range); 2603 break; 2604 default: 2605 ret = -EINVAL; 2606 } 2607 out: 2608 mnt_drop_write_file(file); 2609 return ret; 2610 } 2611 2612 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 2613 { 2614 struct btrfs_ioctl_vol_args *vol_args; 2615 int ret; 2616 2617 if (!capable(CAP_SYS_ADMIN)) 2618 return -EPERM; 2619 2620 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 2621 1)) { 2622 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 2623 } 2624 2625 mutex_lock(&root->fs_info->volume_mutex); 2626 vol_args = memdup_user(arg, sizeof(*vol_args)); 2627 if (IS_ERR(vol_args)) { 2628 ret = PTR_ERR(vol_args); 2629 goto out; 2630 } 2631 2632 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2633 ret = btrfs_init_new_device(root, vol_args->name); 2634 2635 if (!ret) 2636 btrfs_info(root->fs_info, "disk added %s",vol_args->name); 2637 2638 kfree(vol_args); 2639 out: 2640 mutex_unlock(&root->fs_info->volume_mutex); 2641 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 2642 return ret; 2643 } 2644 2645 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) 2646 { 2647 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 2648 struct btrfs_ioctl_vol_args *vol_args; 2649 int ret; 2650 2651 if (!capable(CAP_SYS_ADMIN)) 2652 return -EPERM; 2653 2654 ret = mnt_want_write_file(file); 2655 if (ret) 2656 return ret; 2657 2658 vol_args = memdup_user(arg, sizeof(*vol_args)); 2659 if (IS_ERR(vol_args)) { 2660 ret = PTR_ERR(vol_args); 2661 goto err_drop; 2662 } 2663 2664 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2665 2666 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 2667 1)) { 2668 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 2669 goto out; 2670 } 2671 2672 mutex_lock(&root->fs_info->volume_mutex); 2673 ret = btrfs_rm_device(root, vol_args->name); 2674 mutex_unlock(&root->fs_info->volume_mutex); 2675 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 2676 2677 if (!ret) 2678 btrfs_info(root->fs_info, "disk deleted %s",vol_args->name); 2679 2680 out: 2681 kfree(vol_args); 2682 err_drop: 2683 mnt_drop_write_file(file); 2684 return ret; 2685 } 2686 2687 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) 2688 { 2689 struct btrfs_ioctl_fs_info_args *fi_args; 2690 struct btrfs_device *device; 2691 struct btrfs_device *next; 2692 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2693 int ret = 0; 2694 2695 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 2696 if (!fi_args) 2697 return -ENOMEM; 2698 2699 mutex_lock(&fs_devices->device_list_mutex); 2700 fi_args->num_devices = fs_devices->num_devices; 2701 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); 2702 2703 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 2704 if (device->devid > fi_args->max_id) 2705 fi_args->max_id = device->devid; 2706 } 2707 mutex_unlock(&fs_devices->device_list_mutex); 2708 2709 fi_args->nodesize = root->fs_info->super_copy->nodesize; 2710 fi_args->sectorsize = root->fs_info->super_copy->sectorsize; 2711 fi_args->clone_alignment = root->fs_info->super_copy->sectorsize; 2712 2713 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 2714 ret = -EFAULT; 2715 2716 kfree(fi_args); 2717 return ret; 2718 } 2719 2720 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) 2721 { 2722 struct btrfs_ioctl_dev_info_args *di_args; 2723 struct btrfs_device *dev; 2724 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2725 int ret = 0; 2726 char *s_uuid = NULL; 2727 2728 di_args = memdup_user(arg, sizeof(*di_args)); 2729 if (IS_ERR(di_args)) 2730 return PTR_ERR(di_args); 2731 2732 if (!btrfs_is_empty_uuid(di_args->uuid)) 2733 s_uuid = di_args->uuid; 2734 2735 mutex_lock(&fs_devices->device_list_mutex); 2736 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL); 2737 2738 if (!dev) { 2739 ret = -ENODEV; 2740 goto out; 2741 } 2742 2743 di_args->devid = dev->devid; 2744 di_args->bytes_used = btrfs_device_get_bytes_used(dev); 2745 di_args->total_bytes = btrfs_device_get_total_bytes(dev); 2746 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 2747 if (dev->name) { 2748 struct rcu_string *name; 2749 2750 rcu_read_lock(); 2751 name = rcu_dereference(dev->name); 2752 strncpy(di_args->path, name->str, sizeof(di_args->path)); 2753 rcu_read_unlock(); 2754 di_args->path[sizeof(di_args->path) - 1] = 0; 2755 } else { 2756 di_args->path[0] = '\0'; 2757 } 2758 2759 out: 2760 mutex_unlock(&fs_devices->device_list_mutex); 2761 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 2762 ret = -EFAULT; 2763 2764 kfree(di_args); 2765 return ret; 2766 } 2767 2768 static struct page *extent_same_get_page(struct inode *inode, u64 off) 2769 { 2770 struct page *page; 2771 pgoff_t index; 2772 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree; 2773 2774 index = off >> PAGE_CACHE_SHIFT; 2775 2776 page = grab_cache_page(inode->i_mapping, index); 2777 if (!page) 2778 return NULL; 2779 2780 if (!PageUptodate(page)) { 2781 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent, 2782 0)) 2783 return NULL; 2784 lock_page(page); 2785 if (!PageUptodate(page)) { 2786 unlock_page(page); 2787 page_cache_release(page); 2788 return NULL; 2789 } 2790 } 2791 unlock_page(page); 2792 2793 return page; 2794 } 2795 2796 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len) 2797 { 2798 /* do any pending delalloc/csum calc on src, one way or 2799 another, and lock file content */ 2800 while (1) { 2801 struct btrfs_ordered_extent *ordered; 2802 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); 2803 ordered = btrfs_lookup_first_ordered_extent(inode, 2804 off + len - 1); 2805 if ((!ordered || 2806 ordered->file_offset + ordered->len <= off || 2807 ordered->file_offset >= off + len) && 2808 !test_range_bit(&BTRFS_I(inode)->io_tree, off, 2809 off + len - 1, EXTENT_DELALLOC, 0, NULL)) { 2810 if (ordered) 2811 btrfs_put_ordered_extent(ordered); 2812 break; 2813 } 2814 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); 2815 if (ordered) 2816 btrfs_put_ordered_extent(ordered); 2817 btrfs_wait_ordered_range(inode, off, len); 2818 } 2819 } 2820 2821 static void btrfs_double_unlock(struct inode *inode1, u64 loff1, 2822 struct inode *inode2, u64 loff2, u64 len) 2823 { 2824 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1); 2825 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1); 2826 2827 mutex_unlock(&inode1->i_mutex); 2828 mutex_unlock(&inode2->i_mutex); 2829 } 2830 2831 static void btrfs_double_lock(struct inode *inode1, u64 loff1, 2832 struct inode *inode2, u64 loff2, u64 len) 2833 { 2834 if (inode1 < inode2) { 2835 swap(inode1, inode2); 2836 swap(loff1, loff2); 2837 } 2838 2839 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT); 2840 lock_extent_range(inode1, loff1, len); 2841 if (inode1 != inode2) { 2842 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD); 2843 lock_extent_range(inode2, loff2, len); 2844 } 2845 } 2846 2847 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst, 2848 u64 dst_loff, u64 len) 2849 { 2850 int ret = 0; 2851 struct page *src_page, *dst_page; 2852 unsigned int cmp_len = PAGE_CACHE_SIZE; 2853 void *addr, *dst_addr; 2854 2855 while (len) { 2856 if (len < PAGE_CACHE_SIZE) 2857 cmp_len = len; 2858 2859 src_page = extent_same_get_page(src, loff); 2860 if (!src_page) 2861 return -EINVAL; 2862 dst_page = extent_same_get_page(dst, dst_loff); 2863 if (!dst_page) { 2864 page_cache_release(src_page); 2865 return -EINVAL; 2866 } 2867 addr = kmap_atomic(src_page); 2868 dst_addr = kmap_atomic(dst_page); 2869 2870 flush_dcache_page(src_page); 2871 flush_dcache_page(dst_page); 2872 2873 if (memcmp(addr, dst_addr, cmp_len)) 2874 ret = BTRFS_SAME_DATA_DIFFERS; 2875 2876 kunmap_atomic(addr); 2877 kunmap_atomic(dst_addr); 2878 page_cache_release(src_page); 2879 page_cache_release(dst_page); 2880 2881 if (ret) 2882 break; 2883 2884 loff += cmp_len; 2885 dst_loff += cmp_len; 2886 len -= cmp_len; 2887 } 2888 2889 return ret; 2890 } 2891 2892 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen, 2893 u64 olen) 2894 { 2895 u64 len = *plen; 2896 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize; 2897 2898 if (off + olen > inode->i_size || off + olen < off) 2899 return -EINVAL; 2900 2901 /* if we extend to eof, continue to block boundary */ 2902 if (off + len == inode->i_size) 2903 *plen = len = ALIGN(inode->i_size, bs) - off; 2904 2905 /* Check that we are block aligned - btrfs_clone() requires this */ 2906 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs)) 2907 return -EINVAL; 2908 2909 return 0; 2910 } 2911 2912 static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen, 2913 struct inode *dst, u64 dst_loff) 2914 { 2915 int ret; 2916 u64 len = olen; 2917 2918 /* 2919 * btrfs_clone() can't handle extents in the same file 2920 * yet. Once that works, we can drop this check and replace it 2921 * with a check for the same inode, but overlapping extents. 2922 */ 2923 if (src == dst) 2924 return -EINVAL; 2925 2926 if (len == 0) 2927 return 0; 2928 2929 btrfs_double_lock(src, loff, dst, dst_loff, len); 2930 2931 ret = extent_same_check_offsets(src, loff, &len, olen); 2932 if (ret) 2933 goto out_unlock; 2934 2935 ret = extent_same_check_offsets(dst, dst_loff, &len, olen); 2936 if (ret) 2937 goto out_unlock; 2938 2939 /* don't make the dst file partly checksummed */ 2940 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 2941 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) { 2942 ret = -EINVAL; 2943 goto out_unlock; 2944 } 2945 2946 ret = btrfs_cmp_data(src, loff, dst, dst_loff, len); 2947 if (ret == 0) 2948 ret = btrfs_clone(src, dst, loff, olen, len, dst_loff); 2949 2950 out_unlock: 2951 btrfs_double_unlock(src, loff, dst, dst_loff, len); 2952 2953 return ret; 2954 } 2955 2956 #define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024) 2957 2958 static long btrfs_ioctl_file_extent_same(struct file *file, 2959 struct btrfs_ioctl_same_args __user *argp) 2960 { 2961 struct btrfs_ioctl_same_args *same; 2962 struct btrfs_ioctl_same_extent_info *info; 2963 struct inode *src = file_inode(file); 2964 u64 off; 2965 u64 len; 2966 int i; 2967 int ret; 2968 unsigned long size; 2969 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize; 2970 bool is_admin = capable(CAP_SYS_ADMIN); 2971 u16 count; 2972 2973 if (!(file->f_mode & FMODE_READ)) 2974 return -EINVAL; 2975 2976 ret = mnt_want_write_file(file); 2977 if (ret) 2978 return ret; 2979 2980 if (get_user(count, &argp->dest_count)) { 2981 ret = -EFAULT; 2982 goto out; 2983 } 2984 2985 size = offsetof(struct btrfs_ioctl_same_args __user, info[count]); 2986 2987 same = memdup_user(argp, size); 2988 2989 if (IS_ERR(same)) { 2990 ret = PTR_ERR(same); 2991 goto out; 2992 } 2993 2994 off = same->logical_offset; 2995 len = same->length; 2996 2997 /* 2998 * Limit the total length we will dedupe for each operation. 2999 * This is intended to bound the total time spent in this 3000 * ioctl to something sane. 3001 */ 3002 if (len > BTRFS_MAX_DEDUPE_LEN) 3003 len = BTRFS_MAX_DEDUPE_LEN; 3004 3005 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) { 3006 /* 3007 * Btrfs does not support blocksize < page_size. As a 3008 * result, btrfs_cmp_data() won't correctly handle 3009 * this situation without an update. 3010 */ 3011 ret = -EINVAL; 3012 goto out; 3013 } 3014 3015 ret = -EISDIR; 3016 if (S_ISDIR(src->i_mode)) 3017 goto out; 3018 3019 ret = -EACCES; 3020 if (!S_ISREG(src->i_mode)) 3021 goto out; 3022 3023 /* pre-format output fields to sane values */ 3024 for (i = 0; i < count; i++) { 3025 same->info[i].bytes_deduped = 0ULL; 3026 same->info[i].status = 0; 3027 } 3028 3029 for (i = 0, info = same->info; i < count; i++, info++) { 3030 struct inode *dst; 3031 struct fd dst_file = fdget(info->fd); 3032 if (!dst_file.file) { 3033 info->status = -EBADF; 3034 continue; 3035 } 3036 dst = file_inode(dst_file.file); 3037 3038 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) { 3039 info->status = -EINVAL; 3040 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) { 3041 info->status = -EXDEV; 3042 } else if (S_ISDIR(dst->i_mode)) { 3043 info->status = -EISDIR; 3044 } else if (!S_ISREG(dst->i_mode)) { 3045 info->status = -EACCES; 3046 } else { 3047 info->status = btrfs_extent_same(src, off, len, dst, 3048 info->logical_offset); 3049 if (info->status == 0) 3050 info->bytes_deduped += len; 3051 } 3052 fdput(dst_file); 3053 } 3054 3055 ret = copy_to_user(argp, same, size); 3056 if (ret) 3057 ret = -EFAULT; 3058 3059 out: 3060 mnt_drop_write_file(file); 3061 return ret; 3062 } 3063 3064 /* Helper to check and see if this root currently has a ref on the given disk 3065 * bytenr. If it does then we need to update the quota for this root. This 3066 * doesn't do anything if quotas aren't enabled. 3067 */ 3068 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, 3069 u64 disko) 3070 { 3071 struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem); 3072 struct ulist *roots; 3073 struct ulist_iterator uiter; 3074 struct ulist_node *root_node = NULL; 3075 int ret; 3076 3077 if (!root->fs_info->quota_enabled) 3078 return 1; 3079 3080 btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem); 3081 ret = btrfs_find_all_roots(trans, root->fs_info, disko, 3082 tree_mod_seq_elem.seq, &roots); 3083 if (ret < 0) 3084 goto out; 3085 ret = 0; 3086 ULIST_ITER_INIT(&uiter); 3087 while ((root_node = ulist_next(roots, &uiter))) { 3088 if (root_node->val == root->objectid) { 3089 ret = 1; 3090 break; 3091 } 3092 } 3093 ulist_free(roots); 3094 out: 3095 btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem); 3096 return ret; 3097 } 3098 3099 static int clone_finish_inode_update(struct btrfs_trans_handle *trans, 3100 struct inode *inode, 3101 u64 endoff, 3102 const u64 destoff, 3103 const u64 olen) 3104 { 3105 struct btrfs_root *root = BTRFS_I(inode)->root; 3106 int ret; 3107 3108 inode_inc_iversion(inode); 3109 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 3110 /* 3111 * We round up to the block size at eof when determining which 3112 * extents to clone above, but shouldn't round up the file size. 3113 */ 3114 if (endoff > destoff + olen) 3115 endoff = destoff + olen; 3116 if (endoff > inode->i_size) 3117 btrfs_i_size_write(inode, endoff); 3118 3119 ret = btrfs_update_inode(trans, root, inode); 3120 if (ret) { 3121 btrfs_abort_transaction(trans, root, ret); 3122 btrfs_end_transaction(trans, root); 3123 goto out; 3124 } 3125 ret = btrfs_end_transaction(trans, root); 3126 out: 3127 return ret; 3128 } 3129 3130 static void clone_update_extent_map(struct inode *inode, 3131 const struct btrfs_trans_handle *trans, 3132 const struct btrfs_path *path, 3133 const u64 hole_offset, 3134 const u64 hole_len) 3135 { 3136 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 3137 struct extent_map *em; 3138 int ret; 3139 3140 em = alloc_extent_map(); 3141 if (!em) { 3142 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3143 &BTRFS_I(inode)->runtime_flags); 3144 return; 3145 } 3146 3147 if (path) { 3148 struct btrfs_file_extent_item *fi; 3149 3150 fi = btrfs_item_ptr(path->nodes[0], path->slots[0], 3151 struct btrfs_file_extent_item); 3152 btrfs_extent_item_to_extent_map(inode, path, fi, false, em); 3153 em->generation = -1; 3154 if (btrfs_file_extent_type(path->nodes[0], fi) == 3155 BTRFS_FILE_EXTENT_INLINE) 3156 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3157 &BTRFS_I(inode)->runtime_flags); 3158 } else { 3159 em->start = hole_offset; 3160 em->len = hole_len; 3161 em->ram_bytes = em->len; 3162 em->orig_start = hole_offset; 3163 em->block_start = EXTENT_MAP_HOLE; 3164 em->block_len = 0; 3165 em->orig_block_len = 0; 3166 em->compress_type = BTRFS_COMPRESS_NONE; 3167 em->generation = trans->transid; 3168 } 3169 3170 while (1) { 3171 write_lock(&em_tree->lock); 3172 ret = add_extent_mapping(em_tree, em, 1); 3173 write_unlock(&em_tree->lock); 3174 if (ret != -EEXIST) { 3175 free_extent_map(em); 3176 break; 3177 } 3178 btrfs_drop_extent_cache(inode, em->start, 3179 em->start + em->len - 1, 0); 3180 } 3181 3182 if (ret) 3183 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3184 &BTRFS_I(inode)->runtime_flags); 3185 } 3186 3187 /** 3188 * btrfs_clone() - clone a range from inode file to another 3189 * 3190 * @src: Inode to clone from 3191 * @inode: Inode to clone to 3192 * @off: Offset within source to start clone from 3193 * @olen: Original length, passed by user, of range to clone 3194 * @olen_aligned: Block-aligned value of olen, extent_same uses 3195 * identical values here 3196 * @destoff: Offset within @inode to start clone 3197 */ 3198 static int btrfs_clone(struct inode *src, struct inode *inode, 3199 const u64 off, const u64 olen, const u64 olen_aligned, 3200 const u64 destoff) 3201 { 3202 struct btrfs_root *root = BTRFS_I(inode)->root; 3203 struct btrfs_path *path = NULL; 3204 struct extent_buffer *leaf; 3205 struct btrfs_trans_handle *trans; 3206 char *buf = NULL; 3207 struct btrfs_key key; 3208 u32 nritems; 3209 int slot; 3210 int ret; 3211 int no_quota; 3212 const u64 len = olen_aligned; 3213 u64 last_disko = 0; 3214 u64 last_dest_end = destoff; 3215 3216 ret = -ENOMEM; 3217 buf = vmalloc(root->nodesize); 3218 if (!buf) 3219 return ret; 3220 3221 path = btrfs_alloc_path(); 3222 if (!path) { 3223 vfree(buf); 3224 return ret; 3225 } 3226 3227 path->reada = 2; 3228 /* clone data */ 3229 key.objectid = btrfs_ino(src); 3230 key.type = BTRFS_EXTENT_DATA_KEY; 3231 key.offset = off; 3232 3233 while (1) { 3234 u64 next_key_min_offset = key.offset + 1; 3235 3236 /* 3237 * note the key will change type as we walk through the 3238 * tree. 3239 */ 3240 path->leave_spinning = 1; 3241 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path, 3242 0, 0); 3243 if (ret < 0) 3244 goto out; 3245 /* 3246 * First search, if no extent item that starts at offset off was 3247 * found but the previous item is an extent item, it's possible 3248 * it might overlap our target range, therefore process it. 3249 */ 3250 if (key.offset == off && ret > 0 && path->slots[0] > 0) { 3251 btrfs_item_key_to_cpu(path->nodes[0], &key, 3252 path->slots[0] - 1); 3253 if (key.type == BTRFS_EXTENT_DATA_KEY) 3254 path->slots[0]--; 3255 } 3256 3257 nritems = btrfs_header_nritems(path->nodes[0]); 3258 process_slot: 3259 no_quota = 1; 3260 if (path->slots[0] >= nritems) { 3261 ret = btrfs_next_leaf(BTRFS_I(src)->root, path); 3262 if (ret < 0) 3263 goto out; 3264 if (ret > 0) 3265 break; 3266 nritems = btrfs_header_nritems(path->nodes[0]); 3267 } 3268 leaf = path->nodes[0]; 3269 slot = path->slots[0]; 3270 3271 btrfs_item_key_to_cpu(leaf, &key, slot); 3272 if (key.type > BTRFS_EXTENT_DATA_KEY || 3273 key.objectid != btrfs_ino(src)) 3274 break; 3275 3276 if (key.type == BTRFS_EXTENT_DATA_KEY) { 3277 struct btrfs_file_extent_item *extent; 3278 int type; 3279 u32 size; 3280 struct btrfs_key new_key; 3281 u64 disko = 0, diskl = 0; 3282 u64 datao = 0, datal = 0; 3283 u8 comp; 3284 u64 drop_start; 3285 3286 extent = btrfs_item_ptr(leaf, slot, 3287 struct btrfs_file_extent_item); 3288 comp = btrfs_file_extent_compression(leaf, extent); 3289 type = btrfs_file_extent_type(leaf, extent); 3290 if (type == BTRFS_FILE_EXTENT_REG || 3291 type == BTRFS_FILE_EXTENT_PREALLOC) { 3292 disko = btrfs_file_extent_disk_bytenr(leaf, 3293 extent); 3294 diskl = btrfs_file_extent_disk_num_bytes(leaf, 3295 extent); 3296 datao = btrfs_file_extent_offset(leaf, extent); 3297 datal = btrfs_file_extent_num_bytes(leaf, 3298 extent); 3299 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 3300 /* take upper bound, may be compressed */ 3301 datal = btrfs_file_extent_ram_bytes(leaf, 3302 extent); 3303 } 3304 3305 /* 3306 * The first search might have left us at an extent 3307 * item that ends before our target range's start, can 3308 * happen if we have holes and NO_HOLES feature enabled. 3309 */ 3310 if (key.offset + datal <= off) { 3311 path->slots[0]++; 3312 goto process_slot; 3313 } else if (key.offset >= off + len) { 3314 break; 3315 } 3316 next_key_min_offset = key.offset + datal; 3317 size = btrfs_item_size_nr(leaf, slot); 3318 read_extent_buffer(leaf, buf, 3319 btrfs_item_ptr_offset(leaf, slot), 3320 size); 3321 3322 btrfs_release_path(path); 3323 path->leave_spinning = 0; 3324 3325 memcpy(&new_key, &key, sizeof(new_key)); 3326 new_key.objectid = btrfs_ino(inode); 3327 if (off <= key.offset) 3328 new_key.offset = key.offset + destoff - off; 3329 else 3330 new_key.offset = destoff; 3331 3332 /* 3333 * Deal with a hole that doesn't have an extent item 3334 * that represents it (NO_HOLES feature enabled). 3335 * This hole is either in the middle of the cloning 3336 * range or at the beginning (fully overlaps it or 3337 * partially overlaps it). 3338 */ 3339 if (new_key.offset != last_dest_end) 3340 drop_start = last_dest_end; 3341 else 3342 drop_start = new_key.offset; 3343 3344 /* 3345 * 1 - adjusting old extent (we may have to split it) 3346 * 1 - add new extent 3347 * 1 - inode update 3348 */ 3349 trans = btrfs_start_transaction(root, 3); 3350 if (IS_ERR(trans)) { 3351 ret = PTR_ERR(trans); 3352 goto out; 3353 } 3354 3355 if (type == BTRFS_FILE_EXTENT_REG || 3356 type == BTRFS_FILE_EXTENT_PREALLOC) { 3357 /* 3358 * a | --- range to clone ---| b 3359 * | ------------- extent ------------- | 3360 */ 3361 3362 /* subtract range b */ 3363 if (key.offset + datal > off + len) 3364 datal = off + len - key.offset; 3365 3366 /* subtract range a */ 3367 if (off > key.offset) { 3368 datao += off - key.offset; 3369 datal -= off - key.offset; 3370 } 3371 3372 ret = btrfs_drop_extents(trans, root, inode, 3373 drop_start, 3374 new_key.offset + datal, 3375 1); 3376 if (ret) { 3377 if (ret != -EOPNOTSUPP) 3378 btrfs_abort_transaction(trans, 3379 root, ret); 3380 btrfs_end_transaction(trans, root); 3381 goto out; 3382 } 3383 3384 ret = btrfs_insert_empty_item(trans, root, path, 3385 &new_key, size); 3386 if (ret) { 3387 btrfs_abort_transaction(trans, root, 3388 ret); 3389 btrfs_end_transaction(trans, root); 3390 goto out; 3391 } 3392 3393 leaf = path->nodes[0]; 3394 slot = path->slots[0]; 3395 write_extent_buffer(leaf, buf, 3396 btrfs_item_ptr_offset(leaf, slot), 3397 size); 3398 3399 extent = btrfs_item_ptr(leaf, slot, 3400 struct btrfs_file_extent_item); 3401 3402 /* disko == 0 means it's a hole */ 3403 if (!disko) 3404 datao = 0; 3405 3406 btrfs_set_file_extent_offset(leaf, extent, 3407 datao); 3408 btrfs_set_file_extent_num_bytes(leaf, extent, 3409 datal); 3410 3411 /* 3412 * We need to look up the roots that point at 3413 * this bytenr and see if the new root does. If 3414 * it does not we need to make sure we update 3415 * quotas appropriately. 3416 */ 3417 if (disko && root != BTRFS_I(src)->root && 3418 disko != last_disko) { 3419 no_quota = check_ref(trans, root, 3420 disko); 3421 if (no_quota < 0) { 3422 btrfs_abort_transaction(trans, 3423 root, 3424 ret); 3425 btrfs_end_transaction(trans, 3426 root); 3427 ret = no_quota; 3428 goto out; 3429 } 3430 } 3431 3432 if (disko) { 3433 inode_add_bytes(inode, datal); 3434 ret = btrfs_inc_extent_ref(trans, root, 3435 disko, diskl, 0, 3436 root->root_key.objectid, 3437 btrfs_ino(inode), 3438 new_key.offset - datao, 3439 no_quota); 3440 if (ret) { 3441 btrfs_abort_transaction(trans, 3442 root, 3443 ret); 3444 btrfs_end_transaction(trans, 3445 root); 3446 goto out; 3447 3448 } 3449 } 3450 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 3451 u64 skip = 0; 3452 u64 trim = 0; 3453 u64 aligned_end = 0; 3454 3455 if (off > key.offset) { 3456 skip = off - key.offset; 3457 new_key.offset += skip; 3458 } 3459 3460 if (key.offset + datal > off + len) 3461 trim = key.offset + datal - (off + len); 3462 3463 if (comp && (skip || trim)) { 3464 ret = -EINVAL; 3465 btrfs_end_transaction(trans, root); 3466 goto out; 3467 } 3468 size -= skip + trim; 3469 datal -= skip + trim; 3470 3471 aligned_end = ALIGN(new_key.offset + datal, 3472 root->sectorsize); 3473 ret = btrfs_drop_extents(trans, root, inode, 3474 drop_start, 3475 aligned_end, 3476 1); 3477 if (ret) { 3478 if (ret != -EOPNOTSUPP) 3479 btrfs_abort_transaction(trans, 3480 root, ret); 3481 btrfs_end_transaction(trans, root); 3482 goto out; 3483 } 3484 3485 ret = btrfs_insert_empty_item(trans, root, path, 3486 &new_key, size); 3487 if (ret) { 3488 btrfs_abort_transaction(trans, root, 3489 ret); 3490 btrfs_end_transaction(trans, root); 3491 goto out; 3492 } 3493 3494 if (skip) { 3495 u32 start = 3496 btrfs_file_extent_calc_inline_size(0); 3497 memmove(buf+start, buf+start+skip, 3498 datal); 3499 } 3500 3501 leaf = path->nodes[0]; 3502 slot = path->slots[0]; 3503 write_extent_buffer(leaf, buf, 3504 btrfs_item_ptr_offset(leaf, slot), 3505 size); 3506 inode_add_bytes(inode, datal); 3507 } 3508 3509 /* If we have an implicit hole (NO_HOLES feature). */ 3510 if (drop_start < new_key.offset) 3511 clone_update_extent_map(inode, trans, 3512 NULL, drop_start, 3513 new_key.offset - drop_start); 3514 3515 clone_update_extent_map(inode, trans, path, 0, 0); 3516 3517 btrfs_mark_buffer_dirty(leaf); 3518 btrfs_release_path(path); 3519 3520 last_dest_end = ALIGN(new_key.offset + datal, 3521 root->sectorsize); 3522 ret = clone_finish_inode_update(trans, inode, 3523 last_dest_end, 3524 destoff, olen); 3525 if (ret) 3526 goto out; 3527 if (new_key.offset + datal >= destoff + len) 3528 break; 3529 } 3530 btrfs_release_path(path); 3531 key.offset = next_key_min_offset; 3532 } 3533 ret = 0; 3534 3535 if (last_dest_end < destoff + len) { 3536 /* 3537 * We have an implicit hole (NO_HOLES feature is enabled) that 3538 * fully or partially overlaps our cloning range at its end. 3539 */ 3540 btrfs_release_path(path); 3541 3542 /* 3543 * 1 - remove extent(s) 3544 * 1 - inode update 3545 */ 3546 trans = btrfs_start_transaction(root, 2); 3547 if (IS_ERR(trans)) { 3548 ret = PTR_ERR(trans); 3549 goto out; 3550 } 3551 ret = btrfs_drop_extents(trans, root, inode, 3552 last_dest_end, destoff + len, 1); 3553 if (ret) { 3554 if (ret != -EOPNOTSUPP) 3555 btrfs_abort_transaction(trans, root, ret); 3556 btrfs_end_transaction(trans, root); 3557 goto out; 3558 } 3559 clone_update_extent_map(inode, trans, NULL, last_dest_end, 3560 destoff + len - last_dest_end); 3561 ret = clone_finish_inode_update(trans, inode, destoff + len, 3562 destoff, olen); 3563 } 3564 3565 out: 3566 btrfs_free_path(path); 3567 vfree(buf); 3568 return ret; 3569 } 3570 3571 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 3572 u64 off, u64 olen, u64 destoff) 3573 { 3574 struct inode *inode = file_inode(file); 3575 struct btrfs_root *root = BTRFS_I(inode)->root; 3576 struct fd src_file; 3577 struct inode *src; 3578 int ret; 3579 u64 len = olen; 3580 u64 bs = root->fs_info->sb->s_blocksize; 3581 int same_inode = 0; 3582 3583 /* 3584 * TODO: 3585 * - split compressed inline extents. annoying: we need to 3586 * decompress into destination's address_space (the file offset 3587 * may change, so source mapping won't do), then recompress (or 3588 * otherwise reinsert) a subrange. 3589 * 3590 * - split destination inode's inline extents. The inline extents can 3591 * be either compressed or non-compressed. 3592 */ 3593 3594 /* the destination must be opened for writing */ 3595 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) 3596 return -EINVAL; 3597 3598 if (btrfs_root_readonly(root)) 3599 return -EROFS; 3600 3601 ret = mnt_want_write_file(file); 3602 if (ret) 3603 return ret; 3604 3605 src_file = fdget(srcfd); 3606 if (!src_file.file) { 3607 ret = -EBADF; 3608 goto out_drop_write; 3609 } 3610 3611 ret = -EXDEV; 3612 if (src_file.file->f_path.mnt != file->f_path.mnt) 3613 goto out_fput; 3614 3615 src = file_inode(src_file.file); 3616 3617 ret = -EINVAL; 3618 if (src == inode) 3619 same_inode = 1; 3620 3621 /* the src must be open for reading */ 3622 if (!(src_file.file->f_mode & FMODE_READ)) 3623 goto out_fput; 3624 3625 /* don't make the dst file partly checksummed */ 3626 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 3627 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) 3628 goto out_fput; 3629 3630 ret = -EISDIR; 3631 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 3632 goto out_fput; 3633 3634 ret = -EXDEV; 3635 if (src->i_sb != inode->i_sb) 3636 goto out_fput; 3637 3638 if (!same_inode) { 3639 if (inode < src) { 3640 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); 3641 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); 3642 } else { 3643 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); 3644 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); 3645 } 3646 } else { 3647 mutex_lock(&src->i_mutex); 3648 } 3649 3650 /* determine range to clone */ 3651 ret = -EINVAL; 3652 if (off + len > src->i_size || off + len < off) 3653 goto out_unlock; 3654 if (len == 0) 3655 olen = len = src->i_size - off; 3656 /* if we extend to eof, continue to block boundary */ 3657 if (off + len == src->i_size) 3658 len = ALIGN(src->i_size, bs) - off; 3659 3660 if (len == 0) { 3661 ret = 0; 3662 goto out_unlock; 3663 } 3664 3665 /* verify the end result is block aligned */ 3666 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || 3667 !IS_ALIGNED(destoff, bs)) 3668 goto out_unlock; 3669 3670 /* verify if ranges are overlapped within the same file */ 3671 if (same_inode) { 3672 if (destoff + len > off && destoff < off + len) 3673 goto out_unlock; 3674 } 3675 3676 if (destoff > inode->i_size) { 3677 ret = btrfs_cont_expand(inode, inode->i_size, destoff); 3678 if (ret) 3679 goto out_unlock; 3680 } 3681 3682 /* 3683 * Lock the target range too. Right after we replace the file extent 3684 * items in the fs tree (which now point to the cloned data), we might 3685 * have a worker replace them with extent items relative to a write 3686 * operation that was issued before this clone operation (i.e. confront 3687 * with inode.c:btrfs_finish_ordered_io). 3688 */ 3689 if (same_inode) { 3690 u64 lock_start = min_t(u64, off, destoff); 3691 u64 lock_len = max_t(u64, off, destoff) + len - lock_start; 3692 3693 lock_extent_range(src, lock_start, lock_len); 3694 } else { 3695 lock_extent_range(src, off, len); 3696 lock_extent_range(inode, destoff, len); 3697 } 3698 3699 ret = btrfs_clone(src, inode, off, olen, len, destoff); 3700 3701 if (same_inode) { 3702 u64 lock_start = min_t(u64, off, destoff); 3703 u64 lock_end = max_t(u64, off, destoff) + len - 1; 3704 3705 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end); 3706 } else { 3707 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); 3708 unlock_extent(&BTRFS_I(inode)->io_tree, destoff, 3709 destoff + len - 1); 3710 } 3711 /* 3712 * Truncate page cache pages so that future reads will see the cloned 3713 * data immediately and not the previous data. 3714 */ 3715 truncate_inode_pages_range(&inode->i_data, destoff, 3716 PAGE_CACHE_ALIGN(destoff + len) - 1); 3717 out_unlock: 3718 if (!same_inode) { 3719 if (inode < src) { 3720 mutex_unlock(&src->i_mutex); 3721 mutex_unlock(&inode->i_mutex); 3722 } else { 3723 mutex_unlock(&inode->i_mutex); 3724 mutex_unlock(&src->i_mutex); 3725 } 3726 } else { 3727 mutex_unlock(&src->i_mutex); 3728 } 3729 out_fput: 3730 fdput(src_file); 3731 out_drop_write: 3732 mnt_drop_write_file(file); 3733 return ret; 3734 } 3735 3736 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) 3737 { 3738 struct btrfs_ioctl_clone_range_args args; 3739 3740 if (copy_from_user(&args, argp, sizeof(args))) 3741 return -EFAULT; 3742 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, 3743 args.src_length, args.dest_offset); 3744 } 3745 3746 /* 3747 * there are many ways the trans_start and trans_end ioctls can lead 3748 * to deadlocks. They should only be used by applications that 3749 * basically own the machine, and have a very in depth understanding 3750 * of all the possible deadlocks and enospc problems. 3751 */ 3752 static long btrfs_ioctl_trans_start(struct file *file) 3753 { 3754 struct inode *inode = file_inode(file); 3755 struct btrfs_root *root = BTRFS_I(inode)->root; 3756 struct btrfs_trans_handle *trans; 3757 int ret; 3758 3759 ret = -EPERM; 3760 if (!capable(CAP_SYS_ADMIN)) 3761 goto out; 3762 3763 ret = -EINPROGRESS; 3764 if (file->private_data) 3765 goto out; 3766 3767 ret = -EROFS; 3768 if (btrfs_root_readonly(root)) 3769 goto out; 3770 3771 ret = mnt_want_write_file(file); 3772 if (ret) 3773 goto out; 3774 3775 atomic_inc(&root->fs_info->open_ioctl_trans); 3776 3777 ret = -ENOMEM; 3778 trans = btrfs_start_ioctl_transaction(root); 3779 if (IS_ERR(trans)) 3780 goto out_drop; 3781 3782 file->private_data = trans; 3783 return 0; 3784 3785 out_drop: 3786 atomic_dec(&root->fs_info->open_ioctl_trans); 3787 mnt_drop_write_file(file); 3788 out: 3789 return ret; 3790 } 3791 3792 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) 3793 { 3794 struct inode *inode = file_inode(file); 3795 struct btrfs_root *root = BTRFS_I(inode)->root; 3796 struct btrfs_root *new_root; 3797 struct btrfs_dir_item *di; 3798 struct btrfs_trans_handle *trans; 3799 struct btrfs_path *path; 3800 struct btrfs_key location; 3801 struct btrfs_disk_key disk_key; 3802 u64 objectid = 0; 3803 u64 dir_id; 3804 int ret; 3805 3806 if (!capable(CAP_SYS_ADMIN)) 3807 return -EPERM; 3808 3809 ret = mnt_want_write_file(file); 3810 if (ret) 3811 return ret; 3812 3813 if (copy_from_user(&objectid, argp, sizeof(objectid))) { 3814 ret = -EFAULT; 3815 goto out; 3816 } 3817 3818 if (!objectid) 3819 objectid = BTRFS_FS_TREE_OBJECTID; 3820 3821 location.objectid = objectid; 3822 location.type = BTRFS_ROOT_ITEM_KEY; 3823 location.offset = (u64)-1; 3824 3825 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); 3826 if (IS_ERR(new_root)) { 3827 ret = PTR_ERR(new_root); 3828 goto out; 3829 } 3830 3831 path = btrfs_alloc_path(); 3832 if (!path) { 3833 ret = -ENOMEM; 3834 goto out; 3835 } 3836 path->leave_spinning = 1; 3837 3838 trans = btrfs_start_transaction(root, 1); 3839 if (IS_ERR(trans)) { 3840 btrfs_free_path(path); 3841 ret = PTR_ERR(trans); 3842 goto out; 3843 } 3844 3845 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 3846 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, 3847 dir_id, "default", 7, 1); 3848 if (IS_ERR_OR_NULL(di)) { 3849 btrfs_free_path(path); 3850 btrfs_end_transaction(trans, root); 3851 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir" 3852 "item, this isn't going to work"); 3853 ret = -ENOENT; 3854 goto out; 3855 } 3856 3857 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); 3858 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); 3859 btrfs_mark_buffer_dirty(path->nodes[0]); 3860 btrfs_free_path(path); 3861 3862 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL); 3863 btrfs_end_transaction(trans, root); 3864 out: 3865 mnt_drop_write_file(file); 3866 return ret; 3867 } 3868 3869 void btrfs_get_block_group_info(struct list_head *groups_list, 3870 struct btrfs_ioctl_space_info *space) 3871 { 3872 struct btrfs_block_group_cache *block_group; 3873 3874 space->total_bytes = 0; 3875 space->used_bytes = 0; 3876 space->flags = 0; 3877 list_for_each_entry(block_group, groups_list, list) { 3878 space->flags = block_group->flags; 3879 space->total_bytes += block_group->key.offset; 3880 space->used_bytes += 3881 btrfs_block_group_used(&block_group->item); 3882 } 3883 } 3884 3885 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) 3886 { 3887 struct btrfs_ioctl_space_args space_args; 3888 struct btrfs_ioctl_space_info space; 3889 struct btrfs_ioctl_space_info *dest; 3890 struct btrfs_ioctl_space_info *dest_orig; 3891 struct btrfs_ioctl_space_info __user *user_dest; 3892 struct btrfs_space_info *info; 3893 u64 types[] = {BTRFS_BLOCK_GROUP_DATA, 3894 BTRFS_BLOCK_GROUP_SYSTEM, 3895 BTRFS_BLOCK_GROUP_METADATA, 3896 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; 3897 int num_types = 4; 3898 int alloc_size; 3899 int ret = 0; 3900 u64 slot_count = 0; 3901 int i, c; 3902 3903 if (copy_from_user(&space_args, 3904 (struct btrfs_ioctl_space_args __user *)arg, 3905 sizeof(space_args))) 3906 return -EFAULT; 3907 3908 for (i = 0; i < num_types; i++) { 3909 struct btrfs_space_info *tmp; 3910 3911 info = NULL; 3912 rcu_read_lock(); 3913 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 3914 list) { 3915 if (tmp->flags == types[i]) { 3916 info = tmp; 3917 break; 3918 } 3919 } 3920 rcu_read_unlock(); 3921 3922 if (!info) 3923 continue; 3924 3925 down_read(&info->groups_sem); 3926 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 3927 if (!list_empty(&info->block_groups[c])) 3928 slot_count++; 3929 } 3930 up_read(&info->groups_sem); 3931 } 3932 3933 /* 3934 * Global block reserve, exported as a space_info 3935 */ 3936 slot_count++; 3937 3938 /* space_slots == 0 means they are asking for a count */ 3939 if (space_args.space_slots == 0) { 3940 space_args.total_spaces = slot_count; 3941 goto out; 3942 } 3943 3944 slot_count = min_t(u64, space_args.space_slots, slot_count); 3945 3946 alloc_size = sizeof(*dest) * slot_count; 3947 3948 /* we generally have at most 6 or so space infos, one for each raid 3949 * level. So, a whole page should be more than enough for everyone 3950 */ 3951 if (alloc_size > PAGE_CACHE_SIZE) 3952 return -ENOMEM; 3953 3954 space_args.total_spaces = 0; 3955 dest = kmalloc(alloc_size, GFP_NOFS); 3956 if (!dest) 3957 return -ENOMEM; 3958 dest_orig = dest; 3959 3960 /* now we have a buffer to copy into */ 3961 for (i = 0; i < num_types; i++) { 3962 struct btrfs_space_info *tmp; 3963 3964 if (!slot_count) 3965 break; 3966 3967 info = NULL; 3968 rcu_read_lock(); 3969 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 3970 list) { 3971 if (tmp->flags == types[i]) { 3972 info = tmp; 3973 break; 3974 } 3975 } 3976 rcu_read_unlock(); 3977 3978 if (!info) 3979 continue; 3980 down_read(&info->groups_sem); 3981 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 3982 if (!list_empty(&info->block_groups[c])) { 3983 btrfs_get_block_group_info( 3984 &info->block_groups[c], &space); 3985 memcpy(dest, &space, sizeof(space)); 3986 dest++; 3987 space_args.total_spaces++; 3988 slot_count--; 3989 } 3990 if (!slot_count) 3991 break; 3992 } 3993 up_read(&info->groups_sem); 3994 } 3995 3996 /* 3997 * Add global block reserve 3998 */ 3999 if (slot_count) { 4000 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv; 4001 4002 spin_lock(&block_rsv->lock); 4003 space.total_bytes = block_rsv->size; 4004 space.used_bytes = block_rsv->size - block_rsv->reserved; 4005 spin_unlock(&block_rsv->lock); 4006 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV; 4007 memcpy(dest, &space, sizeof(space)); 4008 space_args.total_spaces++; 4009 } 4010 4011 user_dest = (struct btrfs_ioctl_space_info __user *) 4012 (arg + sizeof(struct btrfs_ioctl_space_args)); 4013 4014 if (copy_to_user(user_dest, dest_orig, alloc_size)) 4015 ret = -EFAULT; 4016 4017 kfree(dest_orig); 4018 out: 4019 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) 4020 ret = -EFAULT; 4021 4022 return ret; 4023 } 4024 4025 /* 4026 * there are many ways the trans_start and trans_end ioctls can lead 4027 * to deadlocks. They should only be used by applications that 4028 * basically own the machine, and have a very in depth understanding 4029 * of all the possible deadlocks and enospc problems. 4030 */ 4031 long btrfs_ioctl_trans_end(struct file *file) 4032 { 4033 struct inode *inode = file_inode(file); 4034 struct btrfs_root *root = BTRFS_I(inode)->root; 4035 struct btrfs_trans_handle *trans; 4036 4037 trans = file->private_data; 4038 if (!trans) 4039 return -EINVAL; 4040 file->private_data = NULL; 4041 4042 btrfs_end_transaction(trans, root); 4043 4044 atomic_dec(&root->fs_info->open_ioctl_trans); 4045 4046 mnt_drop_write_file(file); 4047 return 0; 4048 } 4049 4050 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root, 4051 void __user *argp) 4052 { 4053 struct btrfs_trans_handle *trans; 4054 u64 transid; 4055 int ret; 4056 4057 trans = btrfs_attach_transaction_barrier(root); 4058 if (IS_ERR(trans)) { 4059 if (PTR_ERR(trans) != -ENOENT) 4060 return PTR_ERR(trans); 4061 4062 /* No running transaction, don't bother */ 4063 transid = root->fs_info->last_trans_committed; 4064 goto out; 4065 } 4066 transid = trans->transid; 4067 ret = btrfs_commit_transaction_async(trans, root, 0); 4068 if (ret) { 4069 btrfs_end_transaction(trans, root); 4070 return ret; 4071 } 4072 out: 4073 if (argp) 4074 if (copy_to_user(argp, &transid, sizeof(transid))) 4075 return -EFAULT; 4076 return 0; 4077 } 4078 4079 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root, 4080 void __user *argp) 4081 { 4082 u64 transid; 4083 4084 if (argp) { 4085 if (copy_from_user(&transid, argp, sizeof(transid))) 4086 return -EFAULT; 4087 } else { 4088 transid = 0; /* current trans */ 4089 } 4090 return btrfs_wait_for_commit(root, transid); 4091 } 4092 4093 static long btrfs_ioctl_scrub(struct file *file, void __user *arg) 4094 { 4095 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4096 struct btrfs_ioctl_scrub_args *sa; 4097 int ret; 4098 4099 if (!capable(CAP_SYS_ADMIN)) 4100 return -EPERM; 4101 4102 sa = memdup_user(arg, sizeof(*sa)); 4103 if (IS_ERR(sa)) 4104 return PTR_ERR(sa); 4105 4106 if (!(sa->flags & BTRFS_SCRUB_READONLY)) { 4107 ret = mnt_want_write_file(file); 4108 if (ret) 4109 goto out; 4110 } 4111 4112 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end, 4113 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY, 4114 0); 4115 4116 if (copy_to_user(arg, sa, sizeof(*sa))) 4117 ret = -EFAULT; 4118 4119 if (!(sa->flags & BTRFS_SCRUB_READONLY)) 4120 mnt_drop_write_file(file); 4121 out: 4122 kfree(sa); 4123 return ret; 4124 } 4125 4126 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg) 4127 { 4128 if (!capable(CAP_SYS_ADMIN)) 4129 return -EPERM; 4130 4131 return btrfs_scrub_cancel(root->fs_info); 4132 } 4133 4134 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, 4135 void __user *arg) 4136 { 4137 struct btrfs_ioctl_scrub_args *sa; 4138 int ret; 4139 4140 if (!capable(CAP_SYS_ADMIN)) 4141 return -EPERM; 4142 4143 sa = memdup_user(arg, sizeof(*sa)); 4144 if (IS_ERR(sa)) 4145 return PTR_ERR(sa); 4146 4147 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress); 4148 4149 if (copy_to_user(arg, sa, sizeof(*sa))) 4150 ret = -EFAULT; 4151 4152 kfree(sa); 4153 return ret; 4154 } 4155 4156 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root, 4157 void __user *arg) 4158 { 4159 struct btrfs_ioctl_get_dev_stats *sa; 4160 int ret; 4161 4162 sa = memdup_user(arg, sizeof(*sa)); 4163 if (IS_ERR(sa)) 4164 return PTR_ERR(sa); 4165 4166 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) { 4167 kfree(sa); 4168 return -EPERM; 4169 } 4170 4171 ret = btrfs_get_dev_stats(root, sa); 4172 4173 if (copy_to_user(arg, sa, sizeof(*sa))) 4174 ret = -EFAULT; 4175 4176 kfree(sa); 4177 return ret; 4178 } 4179 4180 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg) 4181 { 4182 struct btrfs_ioctl_dev_replace_args *p; 4183 int ret; 4184 4185 if (!capable(CAP_SYS_ADMIN)) 4186 return -EPERM; 4187 4188 p = memdup_user(arg, sizeof(*p)); 4189 if (IS_ERR(p)) 4190 return PTR_ERR(p); 4191 4192 switch (p->cmd) { 4193 case BTRFS_IOCTL_DEV_REPLACE_CMD_START: 4194 if (root->fs_info->sb->s_flags & MS_RDONLY) { 4195 ret = -EROFS; 4196 goto out; 4197 } 4198 if (atomic_xchg( 4199 &root->fs_info->mutually_exclusive_operation_running, 4200 1)) { 4201 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 4202 } else { 4203 ret = btrfs_dev_replace_start(root, p); 4204 atomic_set( 4205 &root->fs_info->mutually_exclusive_operation_running, 4206 0); 4207 } 4208 break; 4209 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS: 4210 btrfs_dev_replace_status(root->fs_info, p); 4211 ret = 0; 4212 break; 4213 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL: 4214 ret = btrfs_dev_replace_cancel(root->fs_info, p); 4215 break; 4216 default: 4217 ret = -EINVAL; 4218 break; 4219 } 4220 4221 if (copy_to_user(arg, p, sizeof(*p))) 4222 ret = -EFAULT; 4223 out: 4224 kfree(p); 4225 return ret; 4226 } 4227 4228 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) 4229 { 4230 int ret = 0; 4231 int i; 4232 u64 rel_ptr; 4233 int size; 4234 struct btrfs_ioctl_ino_path_args *ipa = NULL; 4235 struct inode_fs_paths *ipath = NULL; 4236 struct btrfs_path *path; 4237 4238 if (!capable(CAP_DAC_READ_SEARCH)) 4239 return -EPERM; 4240 4241 path = btrfs_alloc_path(); 4242 if (!path) { 4243 ret = -ENOMEM; 4244 goto out; 4245 } 4246 4247 ipa = memdup_user(arg, sizeof(*ipa)); 4248 if (IS_ERR(ipa)) { 4249 ret = PTR_ERR(ipa); 4250 ipa = NULL; 4251 goto out; 4252 } 4253 4254 size = min_t(u32, ipa->size, 4096); 4255 ipath = init_ipath(size, root, path); 4256 if (IS_ERR(ipath)) { 4257 ret = PTR_ERR(ipath); 4258 ipath = NULL; 4259 goto out; 4260 } 4261 4262 ret = paths_from_inode(ipa->inum, ipath); 4263 if (ret < 0) 4264 goto out; 4265 4266 for (i = 0; i < ipath->fspath->elem_cnt; ++i) { 4267 rel_ptr = ipath->fspath->val[i] - 4268 (u64)(unsigned long)ipath->fspath->val; 4269 ipath->fspath->val[i] = rel_ptr; 4270 } 4271 4272 ret = copy_to_user((void *)(unsigned long)ipa->fspath, 4273 (void *)(unsigned long)ipath->fspath, size); 4274 if (ret) { 4275 ret = -EFAULT; 4276 goto out; 4277 } 4278 4279 out: 4280 btrfs_free_path(path); 4281 free_ipath(ipath); 4282 kfree(ipa); 4283 4284 return ret; 4285 } 4286 4287 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) 4288 { 4289 struct btrfs_data_container *inodes = ctx; 4290 const size_t c = 3 * sizeof(u64); 4291 4292 if (inodes->bytes_left >= c) { 4293 inodes->bytes_left -= c; 4294 inodes->val[inodes->elem_cnt] = inum; 4295 inodes->val[inodes->elem_cnt + 1] = offset; 4296 inodes->val[inodes->elem_cnt + 2] = root; 4297 inodes->elem_cnt += 3; 4298 } else { 4299 inodes->bytes_missing += c - inodes->bytes_left; 4300 inodes->bytes_left = 0; 4301 inodes->elem_missed += 3; 4302 } 4303 4304 return 0; 4305 } 4306 4307 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 4308 void __user *arg) 4309 { 4310 int ret = 0; 4311 int size; 4312 struct btrfs_ioctl_logical_ino_args *loi; 4313 struct btrfs_data_container *inodes = NULL; 4314 struct btrfs_path *path = NULL; 4315 4316 if (!capable(CAP_SYS_ADMIN)) 4317 return -EPERM; 4318 4319 loi = memdup_user(arg, sizeof(*loi)); 4320 if (IS_ERR(loi)) { 4321 ret = PTR_ERR(loi); 4322 loi = NULL; 4323 goto out; 4324 } 4325 4326 path = btrfs_alloc_path(); 4327 if (!path) { 4328 ret = -ENOMEM; 4329 goto out; 4330 } 4331 4332 size = min_t(u32, loi->size, 64 * 1024); 4333 inodes = init_data_container(size); 4334 if (IS_ERR(inodes)) { 4335 ret = PTR_ERR(inodes); 4336 inodes = NULL; 4337 goto out; 4338 } 4339 4340 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path, 4341 build_ino_list, inodes); 4342 if (ret == -EINVAL) 4343 ret = -ENOENT; 4344 if (ret < 0) 4345 goto out; 4346 4347 ret = copy_to_user((void *)(unsigned long)loi->inodes, 4348 (void *)(unsigned long)inodes, size); 4349 if (ret) 4350 ret = -EFAULT; 4351 4352 out: 4353 btrfs_free_path(path); 4354 vfree(inodes); 4355 kfree(loi); 4356 4357 return ret; 4358 } 4359 4360 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 4361 struct btrfs_ioctl_balance_args *bargs) 4362 { 4363 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 4364 4365 bargs->flags = bctl->flags; 4366 4367 if (atomic_read(&fs_info->balance_running)) 4368 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 4369 if (atomic_read(&fs_info->balance_pause_req)) 4370 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 4371 if (atomic_read(&fs_info->balance_cancel_req)) 4372 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 4373 4374 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 4375 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 4376 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 4377 4378 if (lock) { 4379 spin_lock(&fs_info->balance_lock); 4380 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 4381 spin_unlock(&fs_info->balance_lock); 4382 } else { 4383 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 4384 } 4385 } 4386 4387 static long btrfs_ioctl_balance(struct file *file, void __user *arg) 4388 { 4389 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4390 struct btrfs_fs_info *fs_info = root->fs_info; 4391 struct btrfs_ioctl_balance_args *bargs; 4392 struct btrfs_balance_control *bctl; 4393 bool need_unlock; /* for mut. excl. ops lock */ 4394 int ret; 4395 4396 if (!capable(CAP_SYS_ADMIN)) 4397 return -EPERM; 4398 4399 ret = mnt_want_write_file(file); 4400 if (ret) 4401 return ret; 4402 4403 again: 4404 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) { 4405 mutex_lock(&fs_info->volume_mutex); 4406 mutex_lock(&fs_info->balance_mutex); 4407 need_unlock = true; 4408 goto locked; 4409 } 4410 4411 /* 4412 * mut. excl. ops lock is locked. Three possibilites: 4413 * (1) some other op is running 4414 * (2) balance is running 4415 * (3) balance is paused -- special case (think resume) 4416 */ 4417 mutex_lock(&fs_info->balance_mutex); 4418 if (fs_info->balance_ctl) { 4419 /* this is either (2) or (3) */ 4420 if (!atomic_read(&fs_info->balance_running)) { 4421 mutex_unlock(&fs_info->balance_mutex); 4422 if (!mutex_trylock(&fs_info->volume_mutex)) 4423 goto again; 4424 mutex_lock(&fs_info->balance_mutex); 4425 4426 if (fs_info->balance_ctl && 4427 !atomic_read(&fs_info->balance_running)) { 4428 /* this is (3) */ 4429 need_unlock = false; 4430 goto locked; 4431 } 4432 4433 mutex_unlock(&fs_info->balance_mutex); 4434 mutex_unlock(&fs_info->volume_mutex); 4435 goto again; 4436 } else { 4437 /* this is (2) */ 4438 mutex_unlock(&fs_info->balance_mutex); 4439 ret = -EINPROGRESS; 4440 goto out; 4441 } 4442 } else { 4443 /* this is (1) */ 4444 mutex_unlock(&fs_info->balance_mutex); 4445 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 4446 goto out; 4447 } 4448 4449 locked: 4450 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running)); 4451 4452 if (arg) { 4453 bargs = memdup_user(arg, sizeof(*bargs)); 4454 if (IS_ERR(bargs)) { 4455 ret = PTR_ERR(bargs); 4456 goto out_unlock; 4457 } 4458 4459 if (bargs->flags & BTRFS_BALANCE_RESUME) { 4460 if (!fs_info->balance_ctl) { 4461 ret = -ENOTCONN; 4462 goto out_bargs; 4463 } 4464 4465 bctl = fs_info->balance_ctl; 4466 spin_lock(&fs_info->balance_lock); 4467 bctl->flags |= BTRFS_BALANCE_RESUME; 4468 spin_unlock(&fs_info->balance_lock); 4469 4470 goto do_balance; 4471 } 4472 } else { 4473 bargs = NULL; 4474 } 4475 4476 if (fs_info->balance_ctl) { 4477 ret = -EINPROGRESS; 4478 goto out_bargs; 4479 } 4480 4481 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 4482 if (!bctl) { 4483 ret = -ENOMEM; 4484 goto out_bargs; 4485 } 4486 4487 bctl->fs_info = fs_info; 4488 if (arg) { 4489 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 4490 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 4491 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 4492 4493 bctl->flags = bargs->flags; 4494 } else { 4495 /* balance everything - no filters */ 4496 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 4497 } 4498 4499 do_balance: 4500 /* 4501 * Ownership of bctl and mutually_exclusive_operation_running 4502 * goes to to btrfs_balance. bctl is freed in __cancel_balance, 4503 * or, if restriper was paused all the way until unmount, in 4504 * free_fs_info. mutually_exclusive_operation_running is 4505 * cleared in __cancel_balance. 4506 */ 4507 need_unlock = false; 4508 4509 ret = btrfs_balance(bctl, bargs); 4510 4511 if (arg) { 4512 if (copy_to_user(arg, bargs, sizeof(*bargs))) 4513 ret = -EFAULT; 4514 } 4515 4516 out_bargs: 4517 kfree(bargs); 4518 out_unlock: 4519 mutex_unlock(&fs_info->balance_mutex); 4520 mutex_unlock(&fs_info->volume_mutex); 4521 if (need_unlock) 4522 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 4523 out: 4524 mnt_drop_write_file(file); 4525 return ret; 4526 } 4527 4528 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) 4529 { 4530 if (!capable(CAP_SYS_ADMIN)) 4531 return -EPERM; 4532 4533 switch (cmd) { 4534 case BTRFS_BALANCE_CTL_PAUSE: 4535 return btrfs_pause_balance(root->fs_info); 4536 case BTRFS_BALANCE_CTL_CANCEL: 4537 return btrfs_cancel_balance(root->fs_info); 4538 } 4539 4540 return -EINVAL; 4541 } 4542 4543 static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 4544 void __user *arg) 4545 { 4546 struct btrfs_fs_info *fs_info = root->fs_info; 4547 struct btrfs_ioctl_balance_args *bargs; 4548 int ret = 0; 4549 4550 if (!capable(CAP_SYS_ADMIN)) 4551 return -EPERM; 4552 4553 mutex_lock(&fs_info->balance_mutex); 4554 if (!fs_info->balance_ctl) { 4555 ret = -ENOTCONN; 4556 goto out; 4557 } 4558 4559 bargs = kzalloc(sizeof(*bargs), GFP_NOFS); 4560 if (!bargs) { 4561 ret = -ENOMEM; 4562 goto out; 4563 } 4564 4565 update_ioctl_balance_args(fs_info, 1, bargs); 4566 4567 if (copy_to_user(arg, bargs, sizeof(*bargs))) 4568 ret = -EFAULT; 4569 4570 kfree(bargs); 4571 out: 4572 mutex_unlock(&fs_info->balance_mutex); 4573 return ret; 4574 } 4575 4576 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg) 4577 { 4578 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4579 struct btrfs_ioctl_quota_ctl_args *sa; 4580 struct btrfs_trans_handle *trans = NULL; 4581 int ret; 4582 int err; 4583 4584 if (!capable(CAP_SYS_ADMIN)) 4585 return -EPERM; 4586 4587 ret = mnt_want_write_file(file); 4588 if (ret) 4589 return ret; 4590 4591 sa = memdup_user(arg, sizeof(*sa)); 4592 if (IS_ERR(sa)) { 4593 ret = PTR_ERR(sa); 4594 goto drop_write; 4595 } 4596 4597 down_write(&root->fs_info->subvol_sem); 4598 trans = btrfs_start_transaction(root->fs_info->tree_root, 2); 4599 if (IS_ERR(trans)) { 4600 ret = PTR_ERR(trans); 4601 goto out; 4602 } 4603 4604 switch (sa->cmd) { 4605 case BTRFS_QUOTA_CTL_ENABLE: 4606 ret = btrfs_quota_enable(trans, root->fs_info); 4607 break; 4608 case BTRFS_QUOTA_CTL_DISABLE: 4609 ret = btrfs_quota_disable(trans, root->fs_info); 4610 break; 4611 default: 4612 ret = -EINVAL; 4613 break; 4614 } 4615 4616 err = btrfs_commit_transaction(trans, root->fs_info->tree_root); 4617 if (err && !ret) 4618 ret = err; 4619 out: 4620 kfree(sa); 4621 up_write(&root->fs_info->subvol_sem); 4622 drop_write: 4623 mnt_drop_write_file(file); 4624 return ret; 4625 } 4626 4627 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg) 4628 { 4629 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4630 struct btrfs_ioctl_qgroup_assign_args *sa; 4631 struct btrfs_trans_handle *trans; 4632 int ret; 4633 int err; 4634 4635 if (!capable(CAP_SYS_ADMIN)) 4636 return -EPERM; 4637 4638 ret = mnt_want_write_file(file); 4639 if (ret) 4640 return ret; 4641 4642 sa = memdup_user(arg, sizeof(*sa)); 4643 if (IS_ERR(sa)) { 4644 ret = PTR_ERR(sa); 4645 goto drop_write; 4646 } 4647 4648 trans = btrfs_join_transaction(root); 4649 if (IS_ERR(trans)) { 4650 ret = PTR_ERR(trans); 4651 goto out; 4652 } 4653 4654 /* FIXME: check if the IDs really exist */ 4655 if (sa->assign) { 4656 ret = btrfs_add_qgroup_relation(trans, root->fs_info, 4657 sa->src, sa->dst); 4658 } else { 4659 ret = btrfs_del_qgroup_relation(trans, root->fs_info, 4660 sa->src, sa->dst); 4661 } 4662 4663 /* update qgroup status and info */ 4664 err = btrfs_run_qgroups(trans, root->fs_info); 4665 if (err < 0) 4666 btrfs_error(root->fs_info, ret, 4667 "failed to update qgroup status and info\n"); 4668 err = btrfs_end_transaction(trans, root); 4669 if (err && !ret) 4670 ret = err; 4671 4672 out: 4673 kfree(sa); 4674 drop_write: 4675 mnt_drop_write_file(file); 4676 return ret; 4677 } 4678 4679 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg) 4680 { 4681 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4682 struct btrfs_ioctl_qgroup_create_args *sa; 4683 struct btrfs_trans_handle *trans; 4684 int ret; 4685 int err; 4686 4687 if (!capable(CAP_SYS_ADMIN)) 4688 return -EPERM; 4689 4690 ret = mnt_want_write_file(file); 4691 if (ret) 4692 return ret; 4693 4694 sa = memdup_user(arg, sizeof(*sa)); 4695 if (IS_ERR(sa)) { 4696 ret = PTR_ERR(sa); 4697 goto drop_write; 4698 } 4699 4700 if (!sa->qgroupid) { 4701 ret = -EINVAL; 4702 goto out; 4703 } 4704 4705 trans = btrfs_join_transaction(root); 4706 if (IS_ERR(trans)) { 4707 ret = PTR_ERR(trans); 4708 goto out; 4709 } 4710 4711 /* FIXME: check if the IDs really exist */ 4712 if (sa->create) { 4713 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid); 4714 } else { 4715 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid); 4716 } 4717 4718 err = btrfs_end_transaction(trans, root); 4719 if (err && !ret) 4720 ret = err; 4721 4722 out: 4723 kfree(sa); 4724 drop_write: 4725 mnt_drop_write_file(file); 4726 return ret; 4727 } 4728 4729 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg) 4730 { 4731 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4732 struct btrfs_ioctl_qgroup_limit_args *sa; 4733 struct btrfs_trans_handle *trans; 4734 int ret; 4735 int err; 4736 u64 qgroupid; 4737 4738 if (!capable(CAP_SYS_ADMIN)) 4739 return -EPERM; 4740 4741 ret = mnt_want_write_file(file); 4742 if (ret) 4743 return ret; 4744 4745 sa = memdup_user(arg, sizeof(*sa)); 4746 if (IS_ERR(sa)) { 4747 ret = PTR_ERR(sa); 4748 goto drop_write; 4749 } 4750 4751 trans = btrfs_join_transaction(root); 4752 if (IS_ERR(trans)) { 4753 ret = PTR_ERR(trans); 4754 goto out; 4755 } 4756 4757 qgroupid = sa->qgroupid; 4758 if (!qgroupid) { 4759 /* take the current subvol as qgroup */ 4760 qgroupid = root->root_key.objectid; 4761 } 4762 4763 /* FIXME: check if the IDs really exist */ 4764 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim); 4765 4766 err = btrfs_end_transaction(trans, root); 4767 if (err && !ret) 4768 ret = err; 4769 4770 out: 4771 kfree(sa); 4772 drop_write: 4773 mnt_drop_write_file(file); 4774 return ret; 4775 } 4776 4777 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg) 4778 { 4779 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4780 struct btrfs_ioctl_quota_rescan_args *qsa; 4781 int ret; 4782 4783 if (!capable(CAP_SYS_ADMIN)) 4784 return -EPERM; 4785 4786 ret = mnt_want_write_file(file); 4787 if (ret) 4788 return ret; 4789 4790 qsa = memdup_user(arg, sizeof(*qsa)); 4791 if (IS_ERR(qsa)) { 4792 ret = PTR_ERR(qsa); 4793 goto drop_write; 4794 } 4795 4796 if (qsa->flags) { 4797 ret = -EINVAL; 4798 goto out; 4799 } 4800 4801 ret = btrfs_qgroup_rescan(root->fs_info); 4802 4803 out: 4804 kfree(qsa); 4805 drop_write: 4806 mnt_drop_write_file(file); 4807 return ret; 4808 } 4809 4810 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg) 4811 { 4812 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4813 struct btrfs_ioctl_quota_rescan_args *qsa; 4814 int ret = 0; 4815 4816 if (!capable(CAP_SYS_ADMIN)) 4817 return -EPERM; 4818 4819 qsa = kzalloc(sizeof(*qsa), GFP_NOFS); 4820 if (!qsa) 4821 return -ENOMEM; 4822 4823 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { 4824 qsa->flags = 1; 4825 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid; 4826 } 4827 4828 if (copy_to_user(arg, qsa, sizeof(*qsa))) 4829 ret = -EFAULT; 4830 4831 kfree(qsa); 4832 return ret; 4833 } 4834 4835 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg) 4836 { 4837 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4838 4839 if (!capable(CAP_SYS_ADMIN)) 4840 return -EPERM; 4841 4842 return btrfs_qgroup_wait_for_completion(root->fs_info); 4843 } 4844 4845 static long _btrfs_ioctl_set_received_subvol(struct file *file, 4846 struct btrfs_ioctl_received_subvol_args *sa) 4847 { 4848 struct inode *inode = file_inode(file); 4849 struct btrfs_root *root = BTRFS_I(inode)->root; 4850 struct btrfs_root_item *root_item = &root->root_item; 4851 struct btrfs_trans_handle *trans; 4852 struct timespec ct = CURRENT_TIME; 4853 int ret = 0; 4854 int received_uuid_changed; 4855 4856 if (!inode_owner_or_capable(inode)) 4857 return -EPERM; 4858 4859 ret = mnt_want_write_file(file); 4860 if (ret < 0) 4861 return ret; 4862 4863 down_write(&root->fs_info->subvol_sem); 4864 4865 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 4866 ret = -EINVAL; 4867 goto out; 4868 } 4869 4870 if (btrfs_root_readonly(root)) { 4871 ret = -EROFS; 4872 goto out; 4873 } 4874 4875 /* 4876 * 1 - root item 4877 * 2 - uuid items (received uuid + subvol uuid) 4878 */ 4879 trans = btrfs_start_transaction(root, 3); 4880 if (IS_ERR(trans)) { 4881 ret = PTR_ERR(trans); 4882 trans = NULL; 4883 goto out; 4884 } 4885 4886 sa->rtransid = trans->transid; 4887 sa->rtime.sec = ct.tv_sec; 4888 sa->rtime.nsec = ct.tv_nsec; 4889 4890 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid, 4891 BTRFS_UUID_SIZE); 4892 if (received_uuid_changed && 4893 !btrfs_is_empty_uuid(root_item->received_uuid)) 4894 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, 4895 root_item->received_uuid, 4896 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 4897 root->root_key.objectid); 4898 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); 4899 btrfs_set_root_stransid(root_item, sa->stransid); 4900 btrfs_set_root_rtransid(root_item, sa->rtransid); 4901 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec); 4902 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec); 4903 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec); 4904 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec); 4905 4906 ret = btrfs_update_root(trans, root->fs_info->tree_root, 4907 &root->root_key, &root->root_item); 4908 if (ret < 0) { 4909 btrfs_end_transaction(trans, root); 4910 goto out; 4911 } 4912 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) { 4913 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root, 4914 sa->uuid, 4915 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 4916 root->root_key.objectid); 4917 if (ret < 0 && ret != -EEXIST) { 4918 btrfs_abort_transaction(trans, root, ret); 4919 goto out; 4920 } 4921 } 4922 ret = btrfs_commit_transaction(trans, root); 4923 if (ret < 0) { 4924 btrfs_abort_transaction(trans, root, ret); 4925 goto out; 4926 } 4927 4928 out: 4929 up_write(&root->fs_info->subvol_sem); 4930 mnt_drop_write_file(file); 4931 return ret; 4932 } 4933 4934 #ifdef CONFIG_64BIT 4935 static long btrfs_ioctl_set_received_subvol_32(struct file *file, 4936 void __user *arg) 4937 { 4938 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL; 4939 struct btrfs_ioctl_received_subvol_args *args64 = NULL; 4940 int ret = 0; 4941 4942 args32 = memdup_user(arg, sizeof(*args32)); 4943 if (IS_ERR(args32)) { 4944 ret = PTR_ERR(args32); 4945 args32 = NULL; 4946 goto out; 4947 } 4948 4949 args64 = kmalloc(sizeof(*args64), GFP_NOFS); 4950 if (!args64) { 4951 ret = -ENOMEM; 4952 goto out; 4953 } 4954 4955 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE); 4956 args64->stransid = args32->stransid; 4957 args64->rtransid = args32->rtransid; 4958 args64->stime.sec = args32->stime.sec; 4959 args64->stime.nsec = args32->stime.nsec; 4960 args64->rtime.sec = args32->rtime.sec; 4961 args64->rtime.nsec = args32->rtime.nsec; 4962 args64->flags = args32->flags; 4963 4964 ret = _btrfs_ioctl_set_received_subvol(file, args64); 4965 if (ret) 4966 goto out; 4967 4968 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE); 4969 args32->stransid = args64->stransid; 4970 args32->rtransid = args64->rtransid; 4971 args32->stime.sec = args64->stime.sec; 4972 args32->stime.nsec = args64->stime.nsec; 4973 args32->rtime.sec = args64->rtime.sec; 4974 args32->rtime.nsec = args64->rtime.nsec; 4975 args32->flags = args64->flags; 4976 4977 ret = copy_to_user(arg, args32, sizeof(*args32)); 4978 if (ret) 4979 ret = -EFAULT; 4980 4981 out: 4982 kfree(args32); 4983 kfree(args64); 4984 return ret; 4985 } 4986 #endif 4987 4988 static long btrfs_ioctl_set_received_subvol(struct file *file, 4989 void __user *arg) 4990 { 4991 struct btrfs_ioctl_received_subvol_args *sa = NULL; 4992 int ret = 0; 4993 4994 sa = memdup_user(arg, sizeof(*sa)); 4995 if (IS_ERR(sa)) { 4996 ret = PTR_ERR(sa); 4997 sa = NULL; 4998 goto out; 4999 } 5000 5001 ret = _btrfs_ioctl_set_received_subvol(file, sa); 5002 5003 if (ret) 5004 goto out; 5005 5006 ret = copy_to_user(arg, sa, sizeof(*sa)); 5007 if (ret) 5008 ret = -EFAULT; 5009 5010 out: 5011 kfree(sa); 5012 return ret; 5013 } 5014 5015 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) 5016 { 5017 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5018 size_t len; 5019 int ret; 5020 char label[BTRFS_LABEL_SIZE]; 5021 5022 spin_lock(&root->fs_info->super_lock); 5023 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE); 5024 spin_unlock(&root->fs_info->super_lock); 5025 5026 len = strnlen(label, BTRFS_LABEL_SIZE); 5027 5028 if (len == BTRFS_LABEL_SIZE) { 5029 btrfs_warn(root->fs_info, 5030 "label is too long, return the first %zu bytes", --len); 5031 } 5032 5033 ret = copy_to_user(arg, label, len); 5034 5035 return ret ? -EFAULT : 0; 5036 } 5037 5038 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) 5039 { 5040 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5041 struct btrfs_super_block *super_block = root->fs_info->super_copy; 5042 struct btrfs_trans_handle *trans; 5043 char label[BTRFS_LABEL_SIZE]; 5044 int ret; 5045 5046 if (!capable(CAP_SYS_ADMIN)) 5047 return -EPERM; 5048 5049 if (copy_from_user(label, arg, sizeof(label))) 5050 return -EFAULT; 5051 5052 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) { 5053 btrfs_err(root->fs_info, "unable to set label with more than %d bytes", 5054 BTRFS_LABEL_SIZE - 1); 5055 return -EINVAL; 5056 } 5057 5058 ret = mnt_want_write_file(file); 5059 if (ret) 5060 return ret; 5061 5062 trans = btrfs_start_transaction(root, 0); 5063 if (IS_ERR(trans)) { 5064 ret = PTR_ERR(trans); 5065 goto out_unlock; 5066 } 5067 5068 spin_lock(&root->fs_info->super_lock); 5069 strcpy(super_block->label, label); 5070 spin_unlock(&root->fs_info->super_lock); 5071 ret = btrfs_commit_transaction(trans, root); 5072 5073 out_unlock: 5074 mnt_drop_write_file(file); 5075 return ret; 5076 } 5077 5078 #define INIT_FEATURE_FLAGS(suffix) \ 5079 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \ 5080 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \ 5081 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix } 5082 5083 static int btrfs_ioctl_get_supported_features(struct file *file, 5084 void __user *arg) 5085 { 5086 static struct btrfs_ioctl_feature_flags features[3] = { 5087 INIT_FEATURE_FLAGS(SUPP), 5088 INIT_FEATURE_FLAGS(SAFE_SET), 5089 INIT_FEATURE_FLAGS(SAFE_CLEAR) 5090 }; 5091 5092 if (copy_to_user(arg, &features, sizeof(features))) 5093 return -EFAULT; 5094 5095 return 0; 5096 } 5097 5098 static int btrfs_ioctl_get_features(struct file *file, void __user *arg) 5099 { 5100 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5101 struct btrfs_super_block *super_block = root->fs_info->super_copy; 5102 struct btrfs_ioctl_feature_flags features; 5103 5104 features.compat_flags = btrfs_super_compat_flags(super_block); 5105 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block); 5106 features.incompat_flags = btrfs_super_incompat_flags(super_block); 5107 5108 if (copy_to_user(arg, &features, sizeof(features))) 5109 return -EFAULT; 5110 5111 return 0; 5112 } 5113 5114 static int check_feature_bits(struct btrfs_root *root, 5115 enum btrfs_feature_set set, 5116 u64 change_mask, u64 flags, u64 supported_flags, 5117 u64 safe_set, u64 safe_clear) 5118 { 5119 const char *type = btrfs_feature_set_names[set]; 5120 char *names; 5121 u64 disallowed, unsupported; 5122 u64 set_mask = flags & change_mask; 5123 u64 clear_mask = ~flags & change_mask; 5124 5125 unsupported = set_mask & ~supported_flags; 5126 if (unsupported) { 5127 names = btrfs_printable_features(set, unsupported); 5128 if (names) { 5129 btrfs_warn(root->fs_info, 5130 "this kernel does not support the %s feature bit%s", 5131 names, strchr(names, ',') ? "s" : ""); 5132 kfree(names); 5133 } else 5134 btrfs_warn(root->fs_info, 5135 "this kernel does not support %s bits 0x%llx", 5136 type, unsupported); 5137 return -EOPNOTSUPP; 5138 } 5139 5140 disallowed = set_mask & ~safe_set; 5141 if (disallowed) { 5142 names = btrfs_printable_features(set, disallowed); 5143 if (names) { 5144 btrfs_warn(root->fs_info, 5145 "can't set the %s feature bit%s while mounted", 5146 names, strchr(names, ',') ? "s" : ""); 5147 kfree(names); 5148 } else 5149 btrfs_warn(root->fs_info, 5150 "can't set %s bits 0x%llx while mounted", 5151 type, disallowed); 5152 return -EPERM; 5153 } 5154 5155 disallowed = clear_mask & ~safe_clear; 5156 if (disallowed) { 5157 names = btrfs_printable_features(set, disallowed); 5158 if (names) { 5159 btrfs_warn(root->fs_info, 5160 "can't clear the %s feature bit%s while mounted", 5161 names, strchr(names, ',') ? "s" : ""); 5162 kfree(names); 5163 } else 5164 btrfs_warn(root->fs_info, 5165 "can't clear %s bits 0x%llx while mounted", 5166 type, disallowed); 5167 return -EPERM; 5168 } 5169 5170 return 0; 5171 } 5172 5173 #define check_feature(root, change_mask, flags, mask_base) \ 5174 check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \ 5175 BTRFS_FEATURE_ ## mask_base ## _SUPP, \ 5176 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \ 5177 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR) 5178 5179 static int btrfs_ioctl_set_features(struct file *file, void __user *arg) 5180 { 5181 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5182 struct btrfs_super_block *super_block = root->fs_info->super_copy; 5183 struct btrfs_ioctl_feature_flags flags[2]; 5184 struct btrfs_trans_handle *trans; 5185 u64 newflags; 5186 int ret; 5187 5188 if (!capable(CAP_SYS_ADMIN)) 5189 return -EPERM; 5190 5191 if (copy_from_user(flags, arg, sizeof(flags))) 5192 return -EFAULT; 5193 5194 /* Nothing to do */ 5195 if (!flags[0].compat_flags && !flags[0].compat_ro_flags && 5196 !flags[0].incompat_flags) 5197 return 0; 5198 5199 ret = check_feature(root, flags[0].compat_flags, 5200 flags[1].compat_flags, COMPAT); 5201 if (ret) 5202 return ret; 5203 5204 ret = check_feature(root, flags[0].compat_ro_flags, 5205 flags[1].compat_ro_flags, COMPAT_RO); 5206 if (ret) 5207 return ret; 5208 5209 ret = check_feature(root, flags[0].incompat_flags, 5210 flags[1].incompat_flags, INCOMPAT); 5211 if (ret) 5212 return ret; 5213 5214 trans = btrfs_start_transaction(root, 0); 5215 if (IS_ERR(trans)) 5216 return PTR_ERR(trans); 5217 5218 spin_lock(&root->fs_info->super_lock); 5219 newflags = btrfs_super_compat_flags(super_block); 5220 newflags |= flags[0].compat_flags & flags[1].compat_flags; 5221 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags); 5222 btrfs_set_super_compat_flags(super_block, newflags); 5223 5224 newflags = btrfs_super_compat_ro_flags(super_block); 5225 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags; 5226 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags); 5227 btrfs_set_super_compat_ro_flags(super_block, newflags); 5228 5229 newflags = btrfs_super_incompat_flags(super_block); 5230 newflags |= flags[0].incompat_flags & flags[1].incompat_flags; 5231 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags); 5232 btrfs_set_super_incompat_flags(super_block, newflags); 5233 spin_unlock(&root->fs_info->super_lock); 5234 5235 return btrfs_commit_transaction(trans, root); 5236 } 5237 5238 long btrfs_ioctl(struct file *file, unsigned int 5239 cmd, unsigned long arg) 5240 { 5241 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5242 void __user *argp = (void __user *)arg; 5243 5244 switch (cmd) { 5245 case FS_IOC_GETFLAGS: 5246 return btrfs_ioctl_getflags(file, argp); 5247 case FS_IOC_SETFLAGS: 5248 return btrfs_ioctl_setflags(file, argp); 5249 case FS_IOC_GETVERSION: 5250 return btrfs_ioctl_getversion(file, argp); 5251 case FITRIM: 5252 return btrfs_ioctl_fitrim(file, argp); 5253 case BTRFS_IOC_SNAP_CREATE: 5254 return btrfs_ioctl_snap_create(file, argp, 0); 5255 case BTRFS_IOC_SNAP_CREATE_V2: 5256 return btrfs_ioctl_snap_create_v2(file, argp, 0); 5257 case BTRFS_IOC_SUBVOL_CREATE: 5258 return btrfs_ioctl_snap_create(file, argp, 1); 5259 case BTRFS_IOC_SUBVOL_CREATE_V2: 5260 return btrfs_ioctl_snap_create_v2(file, argp, 1); 5261 case BTRFS_IOC_SNAP_DESTROY: 5262 return btrfs_ioctl_snap_destroy(file, argp); 5263 case BTRFS_IOC_SUBVOL_GETFLAGS: 5264 return btrfs_ioctl_subvol_getflags(file, argp); 5265 case BTRFS_IOC_SUBVOL_SETFLAGS: 5266 return btrfs_ioctl_subvol_setflags(file, argp); 5267 case BTRFS_IOC_DEFAULT_SUBVOL: 5268 return btrfs_ioctl_default_subvol(file, argp); 5269 case BTRFS_IOC_DEFRAG: 5270 return btrfs_ioctl_defrag(file, NULL); 5271 case BTRFS_IOC_DEFRAG_RANGE: 5272 return btrfs_ioctl_defrag(file, argp); 5273 case BTRFS_IOC_RESIZE: 5274 return btrfs_ioctl_resize(file, argp); 5275 case BTRFS_IOC_ADD_DEV: 5276 return btrfs_ioctl_add_dev(root, argp); 5277 case BTRFS_IOC_RM_DEV: 5278 return btrfs_ioctl_rm_dev(file, argp); 5279 case BTRFS_IOC_FS_INFO: 5280 return btrfs_ioctl_fs_info(root, argp); 5281 case BTRFS_IOC_DEV_INFO: 5282 return btrfs_ioctl_dev_info(root, argp); 5283 case BTRFS_IOC_BALANCE: 5284 return btrfs_ioctl_balance(file, NULL); 5285 case BTRFS_IOC_CLONE: 5286 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 5287 case BTRFS_IOC_CLONE_RANGE: 5288 return btrfs_ioctl_clone_range(file, argp); 5289 case BTRFS_IOC_TRANS_START: 5290 return btrfs_ioctl_trans_start(file); 5291 case BTRFS_IOC_TRANS_END: 5292 return btrfs_ioctl_trans_end(file); 5293 case BTRFS_IOC_TREE_SEARCH: 5294 return btrfs_ioctl_tree_search(file, argp); 5295 case BTRFS_IOC_TREE_SEARCH_V2: 5296 return btrfs_ioctl_tree_search_v2(file, argp); 5297 case BTRFS_IOC_INO_LOOKUP: 5298 return btrfs_ioctl_ino_lookup(file, argp); 5299 case BTRFS_IOC_INO_PATHS: 5300 return btrfs_ioctl_ino_to_path(root, argp); 5301 case BTRFS_IOC_LOGICAL_INO: 5302 return btrfs_ioctl_logical_to_ino(root, argp); 5303 case BTRFS_IOC_SPACE_INFO: 5304 return btrfs_ioctl_space_info(root, argp); 5305 case BTRFS_IOC_SYNC: { 5306 int ret; 5307 5308 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1); 5309 if (ret) 5310 return ret; 5311 ret = btrfs_sync_fs(file_inode(file)->i_sb, 1); 5312 /* 5313 * The transaction thread may want to do more work, 5314 * namely it pokes the cleaner ktread that will start 5315 * processing uncleaned subvols. 5316 */ 5317 wake_up_process(root->fs_info->transaction_kthread); 5318 return ret; 5319 } 5320 case BTRFS_IOC_START_SYNC: 5321 return btrfs_ioctl_start_sync(root, argp); 5322 case BTRFS_IOC_WAIT_SYNC: 5323 return btrfs_ioctl_wait_sync(root, argp); 5324 case BTRFS_IOC_SCRUB: 5325 return btrfs_ioctl_scrub(file, argp); 5326 case BTRFS_IOC_SCRUB_CANCEL: 5327 return btrfs_ioctl_scrub_cancel(root, argp); 5328 case BTRFS_IOC_SCRUB_PROGRESS: 5329 return btrfs_ioctl_scrub_progress(root, argp); 5330 case BTRFS_IOC_BALANCE_V2: 5331 return btrfs_ioctl_balance(file, argp); 5332 case BTRFS_IOC_BALANCE_CTL: 5333 return btrfs_ioctl_balance_ctl(root, arg); 5334 case BTRFS_IOC_BALANCE_PROGRESS: 5335 return btrfs_ioctl_balance_progress(root, argp); 5336 case BTRFS_IOC_SET_RECEIVED_SUBVOL: 5337 return btrfs_ioctl_set_received_subvol(file, argp); 5338 #ifdef CONFIG_64BIT 5339 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32: 5340 return btrfs_ioctl_set_received_subvol_32(file, argp); 5341 #endif 5342 case BTRFS_IOC_SEND: 5343 return btrfs_ioctl_send(file, argp); 5344 case BTRFS_IOC_GET_DEV_STATS: 5345 return btrfs_ioctl_get_dev_stats(root, argp); 5346 case BTRFS_IOC_QUOTA_CTL: 5347 return btrfs_ioctl_quota_ctl(file, argp); 5348 case BTRFS_IOC_QGROUP_ASSIGN: 5349 return btrfs_ioctl_qgroup_assign(file, argp); 5350 case BTRFS_IOC_QGROUP_CREATE: 5351 return btrfs_ioctl_qgroup_create(file, argp); 5352 case BTRFS_IOC_QGROUP_LIMIT: 5353 return btrfs_ioctl_qgroup_limit(file, argp); 5354 case BTRFS_IOC_QUOTA_RESCAN: 5355 return btrfs_ioctl_quota_rescan(file, argp); 5356 case BTRFS_IOC_QUOTA_RESCAN_STATUS: 5357 return btrfs_ioctl_quota_rescan_status(file, argp); 5358 case BTRFS_IOC_QUOTA_RESCAN_WAIT: 5359 return btrfs_ioctl_quota_rescan_wait(file, argp); 5360 case BTRFS_IOC_DEV_REPLACE: 5361 return btrfs_ioctl_dev_replace(root, argp); 5362 case BTRFS_IOC_GET_FSLABEL: 5363 return btrfs_ioctl_get_fslabel(file, argp); 5364 case BTRFS_IOC_SET_FSLABEL: 5365 return btrfs_ioctl_set_fslabel(file, argp); 5366 case BTRFS_IOC_FILE_EXTENT_SAME: 5367 return btrfs_ioctl_file_extent_same(file, argp); 5368 case BTRFS_IOC_GET_SUPPORTED_FEATURES: 5369 return btrfs_ioctl_get_supported_features(file, argp); 5370 case BTRFS_IOC_GET_FEATURES: 5371 return btrfs_ioctl_get_features(file, argp); 5372 case BTRFS_IOC_SET_FEATURES: 5373 return btrfs_ioctl_set_features(file, argp); 5374 } 5375 5376 return -ENOTTY; 5377 } 5378