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 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); 460 /* 461 * The same as the snapshot creation, please see the comment 462 * of create_snapshot(). 463 */ 464 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 465 8, &qgroup_reserved, false); 466 if (ret) 467 return ret; 468 469 trans = btrfs_start_transaction(root, 0); 470 if (IS_ERR(trans)) { 471 ret = PTR_ERR(trans); 472 btrfs_subvolume_release_metadata(root, &block_rsv, 473 qgroup_reserved); 474 return ret; 475 } 476 trans->block_rsv = &block_rsv; 477 trans->bytes_reserved = block_rsv.size; 478 479 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit); 480 if (ret) 481 goto fail; 482 483 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0); 484 if (IS_ERR(leaf)) { 485 ret = PTR_ERR(leaf); 486 goto fail; 487 } 488 489 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header)); 490 btrfs_set_header_bytenr(leaf, leaf->start); 491 btrfs_set_header_generation(leaf, trans->transid); 492 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV); 493 btrfs_set_header_owner(leaf, objectid); 494 495 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(), 496 BTRFS_FSID_SIZE); 497 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 498 btrfs_header_chunk_tree_uuid(leaf), 499 BTRFS_UUID_SIZE); 500 btrfs_mark_buffer_dirty(leaf); 501 502 memset(&root_item, 0, sizeof(root_item)); 503 504 inode_item = &root_item.inode; 505 btrfs_set_stack_inode_generation(inode_item, 1); 506 btrfs_set_stack_inode_size(inode_item, 3); 507 btrfs_set_stack_inode_nlink(inode_item, 1); 508 btrfs_set_stack_inode_nbytes(inode_item, root->nodesize); 509 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); 510 511 btrfs_set_root_flags(&root_item, 0); 512 btrfs_set_root_limit(&root_item, 0); 513 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT); 514 515 btrfs_set_root_bytenr(&root_item, leaf->start); 516 btrfs_set_root_generation(&root_item, trans->transid); 517 btrfs_set_root_level(&root_item, 0); 518 btrfs_set_root_refs(&root_item, 1); 519 btrfs_set_root_used(&root_item, leaf->len); 520 btrfs_set_root_last_snapshot(&root_item, 0); 521 522 btrfs_set_root_generation_v2(&root_item, 523 btrfs_root_generation(&root_item)); 524 uuid_le_gen(&new_uuid); 525 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE); 526 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec); 527 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec); 528 root_item.ctime = root_item.otime; 529 btrfs_set_root_ctransid(&root_item, trans->transid); 530 btrfs_set_root_otransid(&root_item, trans->transid); 531 532 btrfs_tree_unlock(leaf); 533 free_extent_buffer(leaf); 534 leaf = NULL; 535 536 btrfs_set_root_dirid(&root_item, new_dirid); 537 538 key.objectid = objectid; 539 key.offset = 0; 540 key.type = BTRFS_ROOT_ITEM_KEY; 541 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, 542 &root_item); 543 if (ret) 544 goto fail; 545 546 key.offset = (u64)-1; 547 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); 548 if (IS_ERR(new_root)) { 549 btrfs_abort_transaction(trans, root, PTR_ERR(new_root)); 550 ret = PTR_ERR(new_root); 551 goto fail; 552 } 553 554 btrfs_record_root_in_trans(trans, new_root); 555 556 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid); 557 if (ret) { 558 /* We potentially lose an unused inode item here */ 559 btrfs_abort_transaction(trans, root, ret); 560 goto fail; 561 } 562 563 /* 564 * insert the directory item 565 */ 566 ret = btrfs_set_inode_index(dir, &index); 567 if (ret) { 568 btrfs_abort_transaction(trans, root, ret); 569 goto fail; 570 } 571 572 ret = btrfs_insert_dir_item(trans, root, 573 name, namelen, dir, &key, 574 BTRFS_FT_DIR, index); 575 if (ret) { 576 btrfs_abort_transaction(trans, root, ret); 577 goto fail; 578 } 579 580 btrfs_i_size_write(dir, dir->i_size + namelen * 2); 581 ret = btrfs_update_inode(trans, root, dir); 582 BUG_ON(ret); 583 584 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, 585 objectid, root->root_key.objectid, 586 btrfs_ino(dir), index, name, namelen); 587 BUG_ON(ret); 588 589 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root, 590 root_item.uuid, BTRFS_UUID_KEY_SUBVOL, 591 objectid); 592 if (ret) 593 btrfs_abort_transaction(trans, root, ret); 594 595 fail: 596 trans->block_rsv = NULL; 597 trans->bytes_reserved = 0; 598 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); 599 600 if (async_transid) { 601 *async_transid = trans->transid; 602 err = btrfs_commit_transaction_async(trans, root, 1); 603 if (err) 604 err = btrfs_commit_transaction(trans, root); 605 } else { 606 err = btrfs_commit_transaction(trans, root); 607 } 608 if (err && !ret) 609 ret = err; 610 611 if (!ret) { 612 inode = btrfs_lookup_dentry(dir, dentry); 613 if (IS_ERR(inode)) 614 return PTR_ERR(inode); 615 d_instantiate(dentry, inode); 616 } 617 return ret; 618 } 619 620 static void btrfs_wait_nocow_write(struct btrfs_root *root) 621 { 622 s64 writers; 623 DEFINE_WAIT(wait); 624 625 do { 626 prepare_to_wait(&root->subv_writers->wait, &wait, 627 TASK_UNINTERRUPTIBLE); 628 629 writers = percpu_counter_sum(&root->subv_writers->counter); 630 if (writers) 631 schedule(); 632 633 finish_wait(&root->subv_writers->wait, &wait); 634 } while (writers); 635 } 636 637 static int create_snapshot(struct btrfs_root *root, struct inode *dir, 638 struct dentry *dentry, char *name, int namelen, 639 u64 *async_transid, bool readonly, 640 struct btrfs_qgroup_inherit *inherit) 641 { 642 struct inode *inode; 643 struct btrfs_pending_snapshot *pending_snapshot; 644 struct btrfs_trans_handle *trans; 645 int ret; 646 647 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 648 return -EINVAL; 649 650 atomic_inc(&root->will_be_snapshoted); 651 smp_mb__after_atomic(); 652 btrfs_wait_nocow_write(root); 653 654 ret = btrfs_start_delalloc_inodes(root, 0); 655 if (ret) 656 goto out; 657 658 btrfs_wait_ordered_extents(root, -1); 659 660 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); 661 if (!pending_snapshot) { 662 ret = -ENOMEM; 663 goto out; 664 } 665 666 btrfs_init_block_rsv(&pending_snapshot->block_rsv, 667 BTRFS_BLOCK_RSV_TEMP); 668 /* 669 * 1 - parent dir inode 670 * 2 - dir entries 671 * 1 - root item 672 * 2 - root ref/backref 673 * 1 - root of snapshot 674 * 1 - UUID item 675 */ 676 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, 677 &pending_snapshot->block_rsv, 8, 678 &pending_snapshot->qgroup_reserved, 679 false); 680 if (ret) 681 goto free; 682 683 pending_snapshot->dentry = dentry; 684 pending_snapshot->root = root; 685 pending_snapshot->readonly = readonly; 686 pending_snapshot->dir = dir; 687 pending_snapshot->inherit = inherit; 688 689 trans = btrfs_start_transaction(root, 0); 690 if (IS_ERR(trans)) { 691 ret = PTR_ERR(trans); 692 goto fail; 693 } 694 695 spin_lock(&root->fs_info->trans_lock); 696 list_add(&pending_snapshot->list, 697 &trans->transaction->pending_snapshots); 698 spin_unlock(&root->fs_info->trans_lock); 699 if (async_transid) { 700 *async_transid = trans->transid; 701 ret = btrfs_commit_transaction_async(trans, 702 root->fs_info->extent_root, 1); 703 if (ret) 704 ret = btrfs_commit_transaction(trans, root); 705 } else { 706 ret = btrfs_commit_transaction(trans, 707 root->fs_info->extent_root); 708 } 709 if (ret) 710 goto fail; 711 712 ret = pending_snapshot->error; 713 if (ret) 714 goto fail; 715 716 ret = btrfs_orphan_cleanup(pending_snapshot->snap); 717 if (ret) 718 goto fail; 719 720 /* 721 * If orphan cleanup did remove any orphans, it means the tree was 722 * modified and therefore the commit root is not the same as the 723 * current root anymore. This is a problem, because send uses the 724 * commit root and therefore can see inode items that don't exist 725 * in the current root anymore, and for example make calls to 726 * btrfs_iget, which will do tree lookups based on the current root 727 * and not on the commit root. Those lookups will fail, returning a 728 * -ESTALE error, and making send fail with that error. So make sure 729 * a send does not see any orphans we have just removed, and that it 730 * will see the same inodes regardless of whether a transaction 731 * commit happened before it started (meaning that the commit root 732 * will be the same as the current root) or not. 733 */ 734 if (readonly && pending_snapshot->snap->node != 735 pending_snapshot->snap->commit_root) { 736 trans = btrfs_join_transaction(pending_snapshot->snap); 737 if (IS_ERR(trans) && PTR_ERR(trans) != -ENOENT) { 738 ret = PTR_ERR(trans); 739 goto fail; 740 } 741 if (!IS_ERR(trans)) { 742 ret = btrfs_commit_transaction(trans, 743 pending_snapshot->snap); 744 if (ret) 745 goto fail; 746 } 747 } 748 749 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry); 750 if (IS_ERR(inode)) { 751 ret = PTR_ERR(inode); 752 goto fail; 753 } 754 755 d_instantiate(dentry, inode); 756 ret = 0; 757 fail: 758 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root, 759 &pending_snapshot->block_rsv, 760 pending_snapshot->qgroup_reserved); 761 free: 762 kfree(pending_snapshot); 763 out: 764 atomic_dec(&root->will_be_snapshoted); 765 return ret; 766 } 767 768 /* copy of check_sticky in fs/namei.c() 769 * It's inline, so penalty for filesystems that don't use sticky bit is 770 * minimal. 771 */ 772 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode) 773 { 774 kuid_t fsuid = current_fsuid(); 775 776 if (!(dir->i_mode & S_ISVTX)) 777 return 0; 778 if (uid_eq(inode->i_uid, fsuid)) 779 return 0; 780 if (uid_eq(dir->i_uid, fsuid)) 781 return 0; 782 return !capable(CAP_FOWNER); 783 } 784 785 /* copy of may_delete in fs/namei.c() 786 * Check whether we can remove a link victim from directory dir, check 787 * whether the type of victim is right. 788 * 1. We can't do it if dir is read-only (done in permission()) 789 * 2. We should have write and exec permissions on dir 790 * 3. We can't remove anything from append-only dir 791 * 4. We can't do anything with immutable dir (done in permission()) 792 * 5. If the sticky bit on dir is set we should either 793 * a. be owner of dir, or 794 * b. be owner of victim, or 795 * c. have CAP_FOWNER capability 796 * 6. If the victim is append-only or immutable we can't do antyhing with 797 * links pointing to it. 798 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. 799 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. 800 * 9. We can't remove a root or mountpoint. 801 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by 802 * nfs_async_unlink(). 803 */ 804 805 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir) 806 { 807 int error; 808 809 if (!victim->d_inode) 810 return -ENOENT; 811 812 BUG_ON(victim->d_parent->d_inode != dir); 813 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); 814 815 error = inode_permission(dir, MAY_WRITE | MAY_EXEC); 816 if (error) 817 return error; 818 if (IS_APPEND(dir)) 819 return -EPERM; 820 if (btrfs_check_sticky(dir, victim->d_inode)|| 821 IS_APPEND(victim->d_inode)|| 822 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) 823 return -EPERM; 824 if (isdir) { 825 if (!S_ISDIR(victim->d_inode->i_mode)) 826 return -ENOTDIR; 827 if (IS_ROOT(victim)) 828 return -EBUSY; 829 } else if (S_ISDIR(victim->d_inode->i_mode)) 830 return -EISDIR; 831 if (IS_DEADDIR(dir)) 832 return -ENOENT; 833 if (victim->d_flags & DCACHE_NFSFS_RENAMED) 834 return -EBUSY; 835 return 0; 836 } 837 838 /* copy of may_create in fs/namei.c() */ 839 static inline int btrfs_may_create(struct inode *dir, struct dentry *child) 840 { 841 if (child->d_inode) 842 return -EEXIST; 843 if (IS_DEADDIR(dir)) 844 return -ENOENT; 845 return inode_permission(dir, MAY_WRITE | MAY_EXEC); 846 } 847 848 /* 849 * Create a new subvolume below @parent. This is largely modeled after 850 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup 851 * inside this filesystem so it's quite a bit simpler. 852 */ 853 static noinline int btrfs_mksubvol(struct path *parent, 854 char *name, int namelen, 855 struct btrfs_root *snap_src, 856 u64 *async_transid, bool readonly, 857 struct btrfs_qgroup_inherit *inherit) 858 { 859 struct inode *dir = parent->dentry->d_inode; 860 struct dentry *dentry; 861 int error; 862 863 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT); 864 if (error == -EINTR) 865 return error; 866 867 dentry = lookup_one_len(name, parent->dentry, namelen); 868 error = PTR_ERR(dentry); 869 if (IS_ERR(dentry)) 870 goto out_unlock; 871 872 error = -EEXIST; 873 if (dentry->d_inode) 874 goto out_dput; 875 876 error = btrfs_may_create(dir, dentry); 877 if (error) 878 goto out_dput; 879 880 /* 881 * even if this name doesn't exist, we may get hash collisions. 882 * check for them now when we can safely fail 883 */ 884 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root, 885 dir->i_ino, name, 886 namelen); 887 if (error) 888 goto out_dput; 889 890 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 891 892 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) 893 goto out_up_read; 894 895 if (snap_src) { 896 error = create_snapshot(snap_src, dir, dentry, name, namelen, 897 async_transid, readonly, inherit); 898 } else { 899 error = create_subvol(dir, dentry, name, namelen, 900 async_transid, inherit); 901 } 902 if (!error) 903 fsnotify_mkdir(dir, dentry); 904 out_up_read: 905 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); 906 out_dput: 907 dput(dentry); 908 out_unlock: 909 mutex_unlock(&dir->i_mutex); 910 return error; 911 } 912 913 /* 914 * When we're defragging a range, we don't want to kick it off again 915 * if it is really just waiting for delalloc to send it down. 916 * If we find a nice big extent or delalloc range for the bytes in the 917 * file you want to defrag, we return 0 to let you know to skip this 918 * part of the file 919 */ 920 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh) 921 { 922 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 923 struct extent_map *em = NULL; 924 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 925 u64 end; 926 927 read_lock(&em_tree->lock); 928 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); 929 read_unlock(&em_tree->lock); 930 931 if (em) { 932 end = extent_map_end(em); 933 free_extent_map(em); 934 if (end - offset > thresh) 935 return 0; 936 } 937 /* if we already have a nice delalloc here, just stop */ 938 thresh /= 2; 939 end = count_range_bits(io_tree, &offset, offset + thresh, 940 thresh, EXTENT_DELALLOC, 1); 941 if (end >= thresh) 942 return 0; 943 return 1; 944 } 945 946 /* 947 * helper function to walk through a file and find extents 948 * newer than a specific transid, and smaller than thresh. 949 * 950 * This is used by the defragging code to find new and small 951 * extents 952 */ 953 static int find_new_extents(struct btrfs_root *root, 954 struct inode *inode, u64 newer_than, 955 u64 *off, u32 thresh) 956 { 957 struct btrfs_path *path; 958 struct btrfs_key min_key; 959 struct extent_buffer *leaf; 960 struct btrfs_file_extent_item *extent; 961 int type; 962 int ret; 963 u64 ino = btrfs_ino(inode); 964 965 path = btrfs_alloc_path(); 966 if (!path) 967 return -ENOMEM; 968 969 min_key.objectid = ino; 970 min_key.type = BTRFS_EXTENT_DATA_KEY; 971 min_key.offset = *off; 972 973 while (1) { 974 ret = btrfs_search_forward(root, &min_key, path, newer_than); 975 if (ret != 0) 976 goto none; 977 process_slot: 978 if (min_key.objectid != ino) 979 goto none; 980 if (min_key.type != BTRFS_EXTENT_DATA_KEY) 981 goto none; 982 983 leaf = path->nodes[0]; 984 extent = btrfs_item_ptr(leaf, path->slots[0], 985 struct btrfs_file_extent_item); 986 987 type = btrfs_file_extent_type(leaf, extent); 988 if (type == BTRFS_FILE_EXTENT_REG && 989 btrfs_file_extent_num_bytes(leaf, extent) < thresh && 990 check_defrag_in_cache(inode, min_key.offset, thresh)) { 991 *off = min_key.offset; 992 btrfs_free_path(path); 993 return 0; 994 } 995 996 path->slots[0]++; 997 if (path->slots[0] < btrfs_header_nritems(leaf)) { 998 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]); 999 goto process_slot; 1000 } 1001 1002 if (min_key.offset == (u64)-1) 1003 goto none; 1004 1005 min_key.offset++; 1006 btrfs_release_path(path); 1007 } 1008 none: 1009 btrfs_free_path(path); 1010 return -ENOENT; 1011 } 1012 1013 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start) 1014 { 1015 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 1016 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 1017 struct extent_map *em; 1018 u64 len = PAGE_CACHE_SIZE; 1019 1020 /* 1021 * hopefully we have this extent in the tree already, try without 1022 * the full extent lock 1023 */ 1024 read_lock(&em_tree->lock); 1025 em = lookup_extent_mapping(em_tree, start, len); 1026 read_unlock(&em_tree->lock); 1027 1028 if (!em) { 1029 struct extent_state *cached = NULL; 1030 u64 end = start + len - 1; 1031 1032 /* get the big lock and read metadata off disk */ 1033 lock_extent_bits(io_tree, start, end, 0, &cached); 1034 em = btrfs_get_extent(inode, NULL, 0, start, len, 0); 1035 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS); 1036 1037 if (IS_ERR(em)) 1038 return NULL; 1039 } 1040 1041 return em; 1042 } 1043 1044 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) 1045 { 1046 struct extent_map *next; 1047 bool ret = true; 1048 1049 /* this is the last extent */ 1050 if (em->start + em->len >= i_size_read(inode)) 1051 return false; 1052 1053 next = defrag_lookup_extent(inode, em->start + em->len); 1054 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) 1055 ret = false; 1056 else if ((em->block_start + em->block_len == next->block_start) && 1057 (em->block_len > 128 * 1024 && next->block_len > 128 * 1024)) 1058 ret = false; 1059 1060 free_extent_map(next); 1061 return ret; 1062 } 1063 1064 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh, 1065 u64 *last_len, u64 *skip, u64 *defrag_end, 1066 int compress) 1067 { 1068 struct extent_map *em; 1069 int ret = 1; 1070 bool next_mergeable = true; 1071 1072 /* 1073 * make sure that once we start defragging an extent, we keep on 1074 * defragging it 1075 */ 1076 if (start < *defrag_end) 1077 return 1; 1078 1079 *skip = 0; 1080 1081 em = defrag_lookup_extent(inode, start); 1082 if (!em) 1083 return 0; 1084 1085 /* this will cover holes, and inline extents */ 1086 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 1087 ret = 0; 1088 goto out; 1089 } 1090 1091 next_mergeable = defrag_check_next_extent(inode, em); 1092 /* 1093 * we hit a real extent, if it is big or the next extent is not a 1094 * real extent, don't bother defragging it 1095 */ 1096 if (!compress && (*last_len == 0 || *last_len >= thresh) && 1097 (em->len >= thresh || !next_mergeable)) 1098 ret = 0; 1099 out: 1100 /* 1101 * last_len ends up being a counter of how many bytes we've defragged. 1102 * every time we choose not to defrag an extent, we reset *last_len 1103 * so that the next tiny extent will force a defrag. 1104 * 1105 * The end result of this is that tiny extents before a single big 1106 * extent will force at least part of that big extent to be defragged. 1107 */ 1108 if (ret) { 1109 *defrag_end = extent_map_end(em); 1110 } else { 1111 *last_len = 0; 1112 *skip = extent_map_end(em); 1113 *defrag_end = 0; 1114 } 1115 1116 free_extent_map(em); 1117 return ret; 1118 } 1119 1120 /* 1121 * it doesn't do much good to defrag one or two pages 1122 * at a time. This pulls in a nice chunk of pages 1123 * to COW and defrag. 1124 * 1125 * It also makes sure the delalloc code has enough 1126 * dirty data to avoid making new small extents as part 1127 * of the defrag 1128 * 1129 * It's a good idea to start RA on this range 1130 * before calling this. 1131 */ 1132 static int cluster_pages_for_defrag(struct inode *inode, 1133 struct page **pages, 1134 unsigned long start_index, 1135 unsigned long num_pages) 1136 { 1137 unsigned long file_end; 1138 u64 isize = i_size_read(inode); 1139 u64 page_start; 1140 u64 page_end; 1141 u64 page_cnt; 1142 int ret; 1143 int i; 1144 int i_done; 1145 struct btrfs_ordered_extent *ordered; 1146 struct extent_state *cached_state = NULL; 1147 struct extent_io_tree *tree; 1148 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 1149 1150 file_end = (isize - 1) >> PAGE_CACHE_SHIFT; 1151 if (!isize || start_index > file_end) 1152 return 0; 1153 1154 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); 1155 1156 ret = btrfs_delalloc_reserve_space(inode, 1157 page_cnt << PAGE_CACHE_SHIFT); 1158 if (ret) 1159 return ret; 1160 i_done = 0; 1161 tree = &BTRFS_I(inode)->io_tree; 1162 1163 /* step one, lock all the pages */ 1164 for (i = 0; i < page_cnt; i++) { 1165 struct page *page; 1166 again: 1167 page = find_or_create_page(inode->i_mapping, 1168 start_index + i, mask); 1169 if (!page) 1170 break; 1171 1172 page_start = page_offset(page); 1173 page_end = page_start + PAGE_CACHE_SIZE - 1; 1174 while (1) { 1175 lock_extent_bits(tree, page_start, page_end, 1176 0, &cached_state); 1177 ordered = btrfs_lookup_ordered_extent(inode, 1178 page_start); 1179 unlock_extent_cached(tree, page_start, page_end, 1180 &cached_state, GFP_NOFS); 1181 if (!ordered) 1182 break; 1183 1184 unlock_page(page); 1185 btrfs_start_ordered_extent(inode, ordered, 1); 1186 btrfs_put_ordered_extent(ordered); 1187 lock_page(page); 1188 /* 1189 * we unlocked the page above, so we need check if 1190 * it was released or not. 1191 */ 1192 if (page->mapping != inode->i_mapping) { 1193 unlock_page(page); 1194 page_cache_release(page); 1195 goto again; 1196 } 1197 } 1198 1199 if (!PageUptodate(page)) { 1200 btrfs_readpage(NULL, page); 1201 lock_page(page); 1202 if (!PageUptodate(page)) { 1203 unlock_page(page); 1204 page_cache_release(page); 1205 ret = -EIO; 1206 break; 1207 } 1208 } 1209 1210 if (page->mapping != inode->i_mapping) { 1211 unlock_page(page); 1212 page_cache_release(page); 1213 goto again; 1214 } 1215 1216 pages[i] = page; 1217 i_done++; 1218 } 1219 if (!i_done || ret) 1220 goto out; 1221 1222 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1223 goto out; 1224 1225 /* 1226 * so now we have a nice long stream of locked 1227 * and up to date pages, lets wait on them 1228 */ 1229 for (i = 0; i < i_done; i++) 1230 wait_on_page_writeback(pages[i]); 1231 1232 page_start = page_offset(pages[0]); 1233 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; 1234 1235 lock_extent_bits(&BTRFS_I(inode)->io_tree, 1236 page_start, page_end - 1, 0, &cached_state); 1237 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 1238 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 1239 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, 1240 &cached_state, GFP_NOFS); 1241 1242 if (i_done != page_cnt) { 1243 spin_lock(&BTRFS_I(inode)->lock); 1244 BTRFS_I(inode)->outstanding_extents++; 1245 spin_unlock(&BTRFS_I(inode)->lock); 1246 btrfs_delalloc_release_space(inode, 1247 (page_cnt - i_done) << PAGE_CACHE_SHIFT); 1248 } 1249 1250 1251 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, 1252 &cached_state, GFP_NOFS); 1253 1254 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 1255 page_start, page_end - 1, &cached_state, 1256 GFP_NOFS); 1257 1258 for (i = 0; i < i_done; i++) { 1259 clear_page_dirty_for_io(pages[i]); 1260 ClearPageChecked(pages[i]); 1261 set_page_extent_mapped(pages[i]); 1262 set_page_dirty(pages[i]); 1263 unlock_page(pages[i]); 1264 page_cache_release(pages[i]); 1265 } 1266 return i_done; 1267 out: 1268 for (i = 0; i < i_done; i++) { 1269 unlock_page(pages[i]); 1270 page_cache_release(pages[i]); 1271 } 1272 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT); 1273 return ret; 1274 1275 } 1276 1277 int btrfs_defrag_file(struct inode *inode, struct file *file, 1278 struct btrfs_ioctl_defrag_range_args *range, 1279 u64 newer_than, unsigned long max_to_defrag) 1280 { 1281 struct btrfs_root *root = BTRFS_I(inode)->root; 1282 struct file_ra_state *ra = NULL; 1283 unsigned long last_index; 1284 u64 isize = i_size_read(inode); 1285 u64 last_len = 0; 1286 u64 skip = 0; 1287 u64 defrag_end = 0; 1288 u64 newer_off = range->start; 1289 unsigned long i; 1290 unsigned long ra_index = 0; 1291 int ret; 1292 int defrag_count = 0; 1293 int compress_type = BTRFS_COMPRESS_ZLIB; 1294 u32 extent_thresh = range->extent_thresh; 1295 unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; 1296 unsigned long cluster = max_cluster; 1297 u64 new_align = ~((u64)128 * 1024 - 1); 1298 struct page **pages = NULL; 1299 1300 if (isize == 0) 1301 return 0; 1302 1303 if (range->start >= isize) 1304 return -EINVAL; 1305 1306 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1307 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1308 return -EINVAL; 1309 if (range->compress_type) 1310 compress_type = range->compress_type; 1311 } 1312 1313 if (extent_thresh == 0) 1314 extent_thresh = 256 * 1024; 1315 1316 /* 1317 * if we were not given a file, allocate a readahead 1318 * context 1319 */ 1320 if (!file) { 1321 ra = kzalloc(sizeof(*ra), GFP_NOFS); 1322 if (!ra) 1323 return -ENOMEM; 1324 file_ra_state_init(ra, inode->i_mapping); 1325 } else { 1326 ra = &file->f_ra; 1327 } 1328 1329 pages = kmalloc_array(max_cluster, sizeof(struct page *), 1330 GFP_NOFS); 1331 if (!pages) { 1332 ret = -ENOMEM; 1333 goto out_ra; 1334 } 1335 1336 /* find the last page to defrag */ 1337 if (range->start + range->len > range->start) { 1338 last_index = min_t(u64, isize - 1, 1339 range->start + range->len - 1) >> PAGE_CACHE_SHIFT; 1340 } else { 1341 last_index = (isize - 1) >> PAGE_CACHE_SHIFT; 1342 } 1343 1344 if (newer_than) { 1345 ret = find_new_extents(root, inode, newer_than, 1346 &newer_off, 64 * 1024); 1347 if (!ret) { 1348 range->start = newer_off; 1349 /* 1350 * we always align our defrag to help keep 1351 * the extents in the file evenly spaced 1352 */ 1353 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1354 } else 1355 goto out_ra; 1356 } else { 1357 i = range->start >> PAGE_CACHE_SHIFT; 1358 } 1359 if (!max_to_defrag) 1360 max_to_defrag = last_index + 1; 1361 1362 /* 1363 * make writeback starts from i, so the defrag range can be 1364 * written sequentially. 1365 */ 1366 if (i < inode->i_mapping->writeback_index) 1367 inode->i_mapping->writeback_index = i; 1368 1369 while (i <= last_index && defrag_count < max_to_defrag && 1370 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) { 1371 /* 1372 * make sure we stop running if someone unmounts 1373 * the FS 1374 */ 1375 if (!(inode->i_sb->s_flags & MS_ACTIVE)) 1376 break; 1377 1378 if (btrfs_defrag_cancelled(root->fs_info)) { 1379 printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n"); 1380 ret = -EAGAIN; 1381 break; 1382 } 1383 1384 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, 1385 extent_thresh, &last_len, &skip, 1386 &defrag_end, range->flags & 1387 BTRFS_DEFRAG_RANGE_COMPRESS)) { 1388 unsigned long next; 1389 /* 1390 * the should_defrag function tells us how much to skip 1391 * bump our counter by the suggested amount 1392 */ 1393 next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE); 1394 i = max(i + 1, next); 1395 continue; 1396 } 1397 1398 if (!newer_than) { 1399 cluster = (PAGE_CACHE_ALIGN(defrag_end) >> 1400 PAGE_CACHE_SHIFT) - i; 1401 cluster = min(cluster, max_cluster); 1402 } else { 1403 cluster = max_cluster; 1404 } 1405 1406 if (i + cluster > ra_index) { 1407 ra_index = max(i, ra_index); 1408 btrfs_force_ra(inode->i_mapping, ra, file, ra_index, 1409 cluster); 1410 ra_index += max_cluster; 1411 } 1412 1413 mutex_lock(&inode->i_mutex); 1414 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) 1415 BTRFS_I(inode)->force_compress = compress_type; 1416 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1417 if (ret < 0) { 1418 mutex_unlock(&inode->i_mutex); 1419 goto out_ra; 1420 } 1421 1422 defrag_count += ret; 1423 balance_dirty_pages_ratelimited(inode->i_mapping); 1424 mutex_unlock(&inode->i_mutex); 1425 1426 if (newer_than) { 1427 if (newer_off == (u64)-1) 1428 break; 1429 1430 if (ret > 0) 1431 i += ret; 1432 1433 newer_off = max(newer_off + 1, 1434 (u64)i << PAGE_CACHE_SHIFT); 1435 1436 ret = find_new_extents(root, inode, 1437 newer_than, &newer_off, 1438 64 * 1024); 1439 if (!ret) { 1440 range->start = newer_off; 1441 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; 1442 } else { 1443 break; 1444 } 1445 } else { 1446 if (ret > 0) { 1447 i += ret; 1448 last_len += ret << PAGE_CACHE_SHIFT; 1449 } else { 1450 i++; 1451 last_len = 0; 1452 } 1453 } 1454 } 1455 1456 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) { 1457 filemap_flush(inode->i_mapping); 1458 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 1459 &BTRFS_I(inode)->runtime_flags)) 1460 filemap_flush(inode->i_mapping); 1461 } 1462 1463 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 1464 /* the filemap_flush will queue IO into the worker threads, but 1465 * we have to make sure the IO is actually started and that 1466 * ordered extents get created before we return 1467 */ 1468 atomic_inc(&root->fs_info->async_submit_draining); 1469 while (atomic_read(&root->fs_info->nr_async_submits) || 1470 atomic_read(&root->fs_info->async_delalloc_pages)) { 1471 wait_event(root->fs_info->async_submit_wait, 1472 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 1473 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 1474 } 1475 atomic_dec(&root->fs_info->async_submit_draining); 1476 } 1477 1478 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1479 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO); 1480 } 1481 1482 ret = defrag_count; 1483 1484 out_ra: 1485 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { 1486 mutex_lock(&inode->i_mutex); 1487 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; 1488 mutex_unlock(&inode->i_mutex); 1489 } 1490 if (!file) 1491 kfree(ra); 1492 kfree(pages); 1493 return ret; 1494 } 1495 1496 static noinline int btrfs_ioctl_resize(struct file *file, 1497 void __user *arg) 1498 { 1499 u64 new_size; 1500 u64 old_size; 1501 u64 devid = 1; 1502 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 1503 struct btrfs_ioctl_vol_args *vol_args; 1504 struct btrfs_trans_handle *trans; 1505 struct btrfs_device *device = NULL; 1506 char *sizestr; 1507 char *retptr; 1508 char *devstr = NULL; 1509 int ret = 0; 1510 int mod = 0; 1511 1512 if (!capable(CAP_SYS_ADMIN)) 1513 return -EPERM; 1514 1515 ret = mnt_want_write_file(file); 1516 if (ret) 1517 return ret; 1518 1519 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1520 1)) { 1521 mnt_drop_write_file(file); 1522 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 1523 } 1524 1525 mutex_lock(&root->fs_info->volume_mutex); 1526 vol_args = memdup_user(arg, sizeof(*vol_args)); 1527 if (IS_ERR(vol_args)) { 1528 ret = PTR_ERR(vol_args); 1529 goto out; 1530 } 1531 1532 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1533 1534 sizestr = vol_args->name; 1535 devstr = strchr(sizestr, ':'); 1536 if (devstr) { 1537 sizestr = devstr + 1; 1538 *devstr = '\0'; 1539 devstr = vol_args->name; 1540 ret = kstrtoull(devstr, 10, &devid); 1541 if (ret) 1542 goto out_free; 1543 if (!devid) { 1544 ret = -EINVAL; 1545 goto out_free; 1546 } 1547 btrfs_info(root->fs_info, "resizing devid %llu", devid); 1548 } 1549 1550 device = btrfs_find_device(root->fs_info, devid, NULL, NULL); 1551 if (!device) { 1552 btrfs_info(root->fs_info, "resizer unable to find device %llu", 1553 devid); 1554 ret = -ENODEV; 1555 goto out_free; 1556 } 1557 1558 if (!device->writeable) { 1559 btrfs_info(root->fs_info, 1560 "resizer unable to apply on readonly device %llu", 1561 devid); 1562 ret = -EPERM; 1563 goto out_free; 1564 } 1565 1566 if (!strcmp(sizestr, "max")) 1567 new_size = device->bdev->bd_inode->i_size; 1568 else { 1569 if (sizestr[0] == '-') { 1570 mod = -1; 1571 sizestr++; 1572 } else if (sizestr[0] == '+') { 1573 mod = 1; 1574 sizestr++; 1575 } 1576 new_size = memparse(sizestr, &retptr); 1577 if (*retptr != '\0' || new_size == 0) { 1578 ret = -EINVAL; 1579 goto out_free; 1580 } 1581 } 1582 1583 if (device->is_tgtdev_for_dev_replace) { 1584 ret = -EPERM; 1585 goto out_free; 1586 } 1587 1588 old_size = btrfs_device_get_total_bytes(device); 1589 1590 if (mod < 0) { 1591 if (new_size > old_size) { 1592 ret = -EINVAL; 1593 goto out_free; 1594 } 1595 new_size = old_size - new_size; 1596 } else if (mod > 0) { 1597 if (new_size > ULLONG_MAX - old_size) { 1598 ret = -ERANGE; 1599 goto out_free; 1600 } 1601 new_size = old_size + new_size; 1602 } 1603 1604 if (new_size < 256 * 1024 * 1024) { 1605 ret = -EINVAL; 1606 goto out_free; 1607 } 1608 if (new_size > device->bdev->bd_inode->i_size) { 1609 ret = -EFBIG; 1610 goto out_free; 1611 } 1612 1613 do_div(new_size, root->sectorsize); 1614 new_size *= root->sectorsize; 1615 1616 printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n", 1617 rcu_str_deref(device->name), new_size); 1618 1619 if (new_size > old_size) { 1620 trans = btrfs_start_transaction(root, 0); 1621 if (IS_ERR(trans)) { 1622 ret = PTR_ERR(trans); 1623 goto out_free; 1624 } 1625 ret = btrfs_grow_device(trans, device, new_size); 1626 btrfs_commit_transaction(trans, root); 1627 } else if (new_size < old_size) { 1628 ret = btrfs_shrink_device(device, new_size); 1629 } /* equal, nothing need to do */ 1630 1631 out_free: 1632 kfree(vol_args); 1633 out: 1634 mutex_unlock(&root->fs_info->volume_mutex); 1635 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 1636 mnt_drop_write_file(file); 1637 return ret; 1638 } 1639 1640 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1641 char *name, unsigned long fd, int subvol, 1642 u64 *transid, bool readonly, 1643 struct btrfs_qgroup_inherit *inherit) 1644 { 1645 int namelen; 1646 int ret = 0; 1647 1648 ret = mnt_want_write_file(file); 1649 if (ret) 1650 goto out; 1651 1652 namelen = strlen(name); 1653 if (strchr(name, '/')) { 1654 ret = -EINVAL; 1655 goto out_drop_write; 1656 } 1657 1658 if (name[0] == '.' && 1659 (namelen == 1 || (name[1] == '.' && namelen == 2))) { 1660 ret = -EEXIST; 1661 goto out_drop_write; 1662 } 1663 1664 if (subvol) { 1665 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1666 NULL, transid, readonly, inherit); 1667 } else { 1668 struct fd src = fdget(fd); 1669 struct inode *src_inode; 1670 if (!src.file) { 1671 ret = -EINVAL; 1672 goto out_drop_write; 1673 } 1674 1675 src_inode = file_inode(src.file); 1676 if (src_inode->i_sb != file_inode(file)->i_sb) { 1677 btrfs_info(BTRFS_I(src_inode)->root->fs_info, 1678 "Snapshot src from another FS"); 1679 ret = -EXDEV; 1680 } else if (!inode_owner_or_capable(src_inode)) { 1681 /* 1682 * Subvolume creation is not restricted, but snapshots 1683 * are limited to own subvolumes only 1684 */ 1685 ret = -EPERM; 1686 } else { 1687 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1688 BTRFS_I(src_inode)->root, 1689 transid, readonly, inherit); 1690 } 1691 fdput(src); 1692 } 1693 out_drop_write: 1694 mnt_drop_write_file(file); 1695 out: 1696 return ret; 1697 } 1698 1699 static noinline int btrfs_ioctl_snap_create(struct file *file, 1700 void __user *arg, int subvol) 1701 { 1702 struct btrfs_ioctl_vol_args *vol_args; 1703 int ret; 1704 1705 vol_args = memdup_user(arg, sizeof(*vol_args)); 1706 if (IS_ERR(vol_args)) 1707 return PTR_ERR(vol_args); 1708 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1709 1710 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1711 vol_args->fd, subvol, 1712 NULL, false, NULL); 1713 1714 kfree(vol_args); 1715 return ret; 1716 } 1717 1718 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1719 void __user *arg, int subvol) 1720 { 1721 struct btrfs_ioctl_vol_args_v2 *vol_args; 1722 int ret; 1723 u64 transid = 0; 1724 u64 *ptr = NULL; 1725 bool readonly = false; 1726 struct btrfs_qgroup_inherit *inherit = NULL; 1727 1728 vol_args = memdup_user(arg, sizeof(*vol_args)); 1729 if (IS_ERR(vol_args)) 1730 return PTR_ERR(vol_args); 1731 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1732 1733 if (vol_args->flags & 1734 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | 1735 BTRFS_SUBVOL_QGROUP_INHERIT)) { 1736 ret = -EOPNOTSUPP; 1737 goto free_args; 1738 } 1739 1740 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1741 ptr = &transid; 1742 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1743 readonly = true; 1744 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { 1745 if (vol_args->size > PAGE_CACHE_SIZE) { 1746 ret = -EINVAL; 1747 goto free_args; 1748 } 1749 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); 1750 if (IS_ERR(inherit)) { 1751 ret = PTR_ERR(inherit); 1752 goto free_args; 1753 } 1754 } 1755 1756 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1757 vol_args->fd, subvol, ptr, 1758 readonly, inherit); 1759 if (ret) 1760 goto free_inherit; 1761 1762 if (ptr && copy_to_user(arg + 1763 offsetof(struct btrfs_ioctl_vol_args_v2, 1764 transid), 1765 ptr, sizeof(*ptr))) 1766 ret = -EFAULT; 1767 1768 free_inherit: 1769 kfree(inherit); 1770 free_args: 1771 kfree(vol_args); 1772 return ret; 1773 } 1774 1775 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1776 void __user *arg) 1777 { 1778 struct inode *inode = file_inode(file); 1779 struct btrfs_root *root = BTRFS_I(inode)->root; 1780 int ret = 0; 1781 u64 flags = 0; 1782 1783 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) 1784 return -EINVAL; 1785 1786 down_read(&root->fs_info->subvol_sem); 1787 if (btrfs_root_readonly(root)) 1788 flags |= BTRFS_SUBVOL_RDONLY; 1789 up_read(&root->fs_info->subvol_sem); 1790 1791 if (copy_to_user(arg, &flags, sizeof(flags))) 1792 ret = -EFAULT; 1793 1794 return ret; 1795 } 1796 1797 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1798 void __user *arg) 1799 { 1800 struct inode *inode = file_inode(file); 1801 struct btrfs_root *root = BTRFS_I(inode)->root; 1802 struct btrfs_trans_handle *trans; 1803 u64 root_flags; 1804 u64 flags; 1805 int ret = 0; 1806 1807 if (!inode_owner_or_capable(inode)) 1808 return -EPERM; 1809 1810 ret = mnt_want_write_file(file); 1811 if (ret) 1812 goto out; 1813 1814 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 1815 ret = -EINVAL; 1816 goto out_drop_write; 1817 } 1818 1819 if (copy_from_user(&flags, arg, sizeof(flags))) { 1820 ret = -EFAULT; 1821 goto out_drop_write; 1822 } 1823 1824 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) { 1825 ret = -EINVAL; 1826 goto out_drop_write; 1827 } 1828 1829 if (flags & ~BTRFS_SUBVOL_RDONLY) { 1830 ret = -EOPNOTSUPP; 1831 goto out_drop_write; 1832 } 1833 1834 down_write(&root->fs_info->subvol_sem); 1835 1836 /* nothing to do */ 1837 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1838 goto out_drop_sem; 1839 1840 root_flags = btrfs_root_flags(&root->root_item); 1841 if (flags & BTRFS_SUBVOL_RDONLY) { 1842 btrfs_set_root_flags(&root->root_item, 1843 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1844 } else { 1845 /* 1846 * Block RO -> RW transition if this subvolume is involved in 1847 * send 1848 */ 1849 spin_lock(&root->root_item_lock); 1850 if (root->send_in_progress == 0) { 1851 btrfs_set_root_flags(&root->root_item, 1852 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1853 spin_unlock(&root->root_item_lock); 1854 } else { 1855 spin_unlock(&root->root_item_lock); 1856 btrfs_warn(root->fs_info, 1857 "Attempt to set subvolume %llu read-write during send", 1858 root->root_key.objectid); 1859 ret = -EPERM; 1860 goto out_drop_sem; 1861 } 1862 } 1863 1864 trans = btrfs_start_transaction(root, 1); 1865 if (IS_ERR(trans)) { 1866 ret = PTR_ERR(trans); 1867 goto out_reset; 1868 } 1869 1870 ret = btrfs_update_root(trans, root->fs_info->tree_root, 1871 &root->root_key, &root->root_item); 1872 1873 btrfs_commit_transaction(trans, root); 1874 out_reset: 1875 if (ret) 1876 btrfs_set_root_flags(&root->root_item, root_flags); 1877 out_drop_sem: 1878 up_write(&root->fs_info->subvol_sem); 1879 out_drop_write: 1880 mnt_drop_write_file(file); 1881 out: 1882 return ret; 1883 } 1884 1885 /* 1886 * helper to check if the subvolume references other subvolumes 1887 */ 1888 static noinline int may_destroy_subvol(struct btrfs_root *root) 1889 { 1890 struct btrfs_path *path; 1891 struct btrfs_dir_item *di; 1892 struct btrfs_key key; 1893 u64 dir_id; 1894 int ret; 1895 1896 path = btrfs_alloc_path(); 1897 if (!path) 1898 return -ENOMEM; 1899 1900 /* Make sure this root isn't set as the default subvol */ 1901 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 1902 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path, 1903 dir_id, "default", 7, 0); 1904 if (di && !IS_ERR(di)) { 1905 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key); 1906 if (key.objectid == root->root_key.objectid) { 1907 ret = -EPERM; 1908 btrfs_err(root->fs_info, "deleting default subvolume " 1909 "%llu is not allowed", key.objectid); 1910 goto out; 1911 } 1912 btrfs_release_path(path); 1913 } 1914 1915 key.objectid = root->root_key.objectid; 1916 key.type = BTRFS_ROOT_REF_KEY; 1917 key.offset = (u64)-1; 1918 1919 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, 1920 &key, path, 0, 0); 1921 if (ret < 0) 1922 goto out; 1923 BUG_ON(ret == 0); 1924 1925 ret = 0; 1926 if (path->slots[0] > 0) { 1927 path->slots[0]--; 1928 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 1929 if (key.objectid == root->root_key.objectid && 1930 key.type == BTRFS_ROOT_REF_KEY) 1931 ret = -ENOTEMPTY; 1932 } 1933 out: 1934 btrfs_free_path(path); 1935 return ret; 1936 } 1937 1938 static noinline int key_in_sk(struct btrfs_key *key, 1939 struct btrfs_ioctl_search_key *sk) 1940 { 1941 struct btrfs_key test; 1942 int ret; 1943 1944 test.objectid = sk->min_objectid; 1945 test.type = sk->min_type; 1946 test.offset = sk->min_offset; 1947 1948 ret = btrfs_comp_cpu_keys(key, &test); 1949 if (ret < 0) 1950 return 0; 1951 1952 test.objectid = sk->max_objectid; 1953 test.type = sk->max_type; 1954 test.offset = sk->max_offset; 1955 1956 ret = btrfs_comp_cpu_keys(key, &test); 1957 if (ret > 0) 1958 return 0; 1959 return 1; 1960 } 1961 1962 static noinline int copy_to_sk(struct btrfs_root *root, 1963 struct btrfs_path *path, 1964 struct btrfs_key *key, 1965 struct btrfs_ioctl_search_key *sk, 1966 size_t *buf_size, 1967 char __user *ubuf, 1968 unsigned long *sk_offset, 1969 int *num_found) 1970 { 1971 u64 found_transid; 1972 struct extent_buffer *leaf; 1973 struct btrfs_ioctl_search_header sh; 1974 unsigned long item_off; 1975 unsigned long item_len; 1976 int nritems; 1977 int i; 1978 int slot; 1979 int ret = 0; 1980 1981 leaf = path->nodes[0]; 1982 slot = path->slots[0]; 1983 nritems = btrfs_header_nritems(leaf); 1984 1985 if (btrfs_header_generation(leaf) > sk->max_transid) { 1986 i = nritems; 1987 goto advance_key; 1988 } 1989 found_transid = btrfs_header_generation(leaf); 1990 1991 for (i = slot; i < nritems; i++) { 1992 item_off = btrfs_item_ptr_offset(leaf, i); 1993 item_len = btrfs_item_size_nr(leaf, i); 1994 1995 btrfs_item_key_to_cpu(leaf, key, i); 1996 if (!key_in_sk(key, sk)) 1997 continue; 1998 1999 if (sizeof(sh) + item_len > *buf_size) { 2000 if (*num_found) { 2001 ret = 1; 2002 goto out; 2003 } 2004 2005 /* 2006 * return one empty item back for v1, which does not 2007 * handle -EOVERFLOW 2008 */ 2009 2010 *buf_size = sizeof(sh) + item_len; 2011 item_len = 0; 2012 ret = -EOVERFLOW; 2013 } 2014 2015 if (sizeof(sh) + item_len + *sk_offset > *buf_size) { 2016 ret = 1; 2017 goto out; 2018 } 2019 2020 sh.objectid = key->objectid; 2021 sh.offset = key->offset; 2022 sh.type = key->type; 2023 sh.len = item_len; 2024 sh.transid = found_transid; 2025 2026 /* copy search result header */ 2027 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) { 2028 ret = -EFAULT; 2029 goto out; 2030 } 2031 2032 *sk_offset += sizeof(sh); 2033 2034 if (item_len) { 2035 char __user *up = ubuf + *sk_offset; 2036 /* copy the item */ 2037 if (read_extent_buffer_to_user(leaf, up, 2038 item_off, item_len)) { 2039 ret = -EFAULT; 2040 goto out; 2041 } 2042 2043 *sk_offset += item_len; 2044 } 2045 (*num_found)++; 2046 2047 if (ret) /* -EOVERFLOW from above */ 2048 goto out; 2049 2050 if (*num_found >= sk->nr_items) { 2051 ret = 1; 2052 goto out; 2053 } 2054 } 2055 advance_key: 2056 ret = 0; 2057 if (key->offset < (u64)-1 && key->offset < sk->max_offset) 2058 key->offset++; 2059 else if (key->type < (u8)-1 && key->type < sk->max_type) { 2060 key->offset = 0; 2061 key->type++; 2062 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { 2063 key->offset = 0; 2064 key->type = 0; 2065 key->objectid++; 2066 } else 2067 ret = 1; 2068 out: 2069 /* 2070 * 0: all items from this leaf copied, continue with next 2071 * 1: * more items can be copied, but unused buffer is too small 2072 * * all items were found 2073 * Either way, it will stops the loop which iterates to the next 2074 * leaf 2075 * -EOVERFLOW: item was to large for buffer 2076 * -EFAULT: could not copy extent buffer back to userspace 2077 */ 2078 return ret; 2079 } 2080 2081 static noinline int search_ioctl(struct inode *inode, 2082 struct btrfs_ioctl_search_key *sk, 2083 size_t *buf_size, 2084 char __user *ubuf) 2085 { 2086 struct btrfs_root *root; 2087 struct btrfs_key key; 2088 struct btrfs_path *path; 2089 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; 2090 int ret; 2091 int num_found = 0; 2092 unsigned long sk_offset = 0; 2093 2094 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) { 2095 *buf_size = sizeof(struct btrfs_ioctl_search_header); 2096 return -EOVERFLOW; 2097 } 2098 2099 path = btrfs_alloc_path(); 2100 if (!path) 2101 return -ENOMEM; 2102 2103 if (sk->tree_id == 0) { 2104 /* search the root of the inode that was passed */ 2105 root = BTRFS_I(inode)->root; 2106 } else { 2107 key.objectid = sk->tree_id; 2108 key.type = BTRFS_ROOT_ITEM_KEY; 2109 key.offset = (u64)-1; 2110 root = btrfs_read_fs_root_no_name(info, &key); 2111 if (IS_ERR(root)) { 2112 printk(KERN_ERR "BTRFS: could not find root %llu\n", 2113 sk->tree_id); 2114 btrfs_free_path(path); 2115 return -ENOENT; 2116 } 2117 } 2118 2119 key.objectid = sk->min_objectid; 2120 key.type = sk->min_type; 2121 key.offset = sk->min_offset; 2122 2123 while (1) { 2124 ret = btrfs_search_forward(root, &key, path, sk->min_transid); 2125 if (ret != 0) { 2126 if (ret > 0) 2127 ret = 0; 2128 goto err; 2129 } 2130 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf, 2131 &sk_offset, &num_found); 2132 btrfs_release_path(path); 2133 if (ret) 2134 break; 2135 2136 } 2137 if (ret > 0) 2138 ret = 0; 2139 err: 2140 sk->nr_items = num_found; 2141 btrfs_free_path(path); 2142 return ret; 2143 } 2144 2145 static noinline int btrfs_ioctl_tree_search(struct file *file, 2146 void __user *argp) 2147 { 2148 struct btrfs_ioctl_search_args __user *uargs; 2149 struct btrfs_ioctl_search_key sk; 2150 struct inode *inode; 2151 int ret; 2152 size_t buf_size; 2153 2154 if (!capable(CAP_SYS_ADMIN)) 2155 return -EPERM; 2156 2157 uargs = (struct btrfs_ioctl_search_args __user *)argp; 2158 2159 if (copy_from_user(&sk, &uargs->key, sizeof(sk))) 2160 return -EFAULT; 2161 2162 buf_size = sizeof(uargs->buf); 2163 2164 inode = file_inode(file); 2165 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf); 2166 2167 /* 2168 * In the origin implementation an overflow is handled by returning a 2169 * search header with a len of zero, so reset ret. 2170 */ 2171 if (ret == -EOVERFLOW) 2172 ret = 0; 2173 2174 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk))) 2175 ret = -EFAULT; 2176 return ret; 2177 } 2178 2179 static noinline int btrfs_ioctl_tree_search_v2(struct file *file, 2180 void __user *argp) 2181 { 2182 struct btrfs_ioctl_search_args_v2 __user *uarg; 2183 struct btrfs_ioctl_search_args_v2 args; 2184 struct inode *inode; 2185 int ret; 2186 size_t buf_size; 2187 const size_t buf_limit = 16 * 1024 * 1024; 2188 2189 if (!capable(CAP_SYS_ADMIN)) 2190 return -EPERM; 2191 2192 /* copy search header and buffer size */ 2193 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp; 2194 if (copy_from_user(&args, uarg, sizeof(args))) 2195 return -EFAULT; 2196 2197 buf_size = args.buf_size; 2198 2199 if (buf_size < sizeof(struct btrfs_ioctl_search_header)) 2200 return -EOVERFLOW; 2201 2202 /* limit result size to 16MB */ 2203 if (buf_size > buf_limit) 2204 buf_size = buf_limit; 2205 2206 inode = file_inode(file); 2207 ret = search_ioctl(inode, &args.key, &buf_size, 2208 (char *)(&uarg->buf[0])); 2209 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key))) 2210 ret = -EFAULT; 2211 else if (ret == -EOVERFLOW && 2212 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size))) 2213 ret = -EFAULT; 2214 2215 return ret; 2216 } 2217 2218 /* 2219 * Search INODE_REFs to identify path name of 'dirid' directory 2220 * in a 'tree_id' tree. and sets path name to 'name'. 2221 */ 2222 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 2223 u64 tree_id, u64 dirid, char *name) 2224 { 2225 struct btrfs_root *root; 2226 struct btrfs_key key; 2227 char *ptr; 2228 int ret = -1; 2229 int slot; 2230 int len; 2231 int total_len = 0; 2232 struct btrfs_inode_ref *iref; 2233 struct extent_buffer *l; 2234 struct btrfs_path *path; 2235 2236 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 2237 name[0]='\0'; 2238 return 0; 2239 } 2240 2241 path = btrfs_alloc_path(); 2242 if (!path) 2243 return -ENOMEM; 2244 2245 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; 2246 2247 key.objectid = tree_id; 2248 key.type = BTRFS_ROOT_ITEM_KEY; 2249 key.offset = (u64)-1; 2250 root = btrfs_read_fs_root_no_name(info, &key); 2251 if (IS_ERR(root)) { 2252 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id); 2253 ret = -ENOENT; 2254 goto out; 2255 } 2256 2257 key.objectid = dirid; 2258 key.type = BTRFS_INODE_REF_KEY; 2259 key.offset = (u64)-1; 2260 2261 while (1) { 2262 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2263 if (ret < 0) 2264 goto out; 2265 else if (ret > 0) { 2266 ret = btrfs_previous_item(root, path, dirid, 2267 BTRFS_INODE_REF_KEY); 2268 if (ret < 0) 2269 goto out; 2270 else if (ret > 0) { 2271 ret = -ENOENT; 2272 goto out; 2273 } 2274 } 2275 2276 l = path->nodes[0]; 2277 slot = path->slots[0]; 2278 btrfs_item_key_to_cpu(l, &key, slot); 2279 2280 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 2281 len = btrfs_inode_ref_name_len(l, iref); 2282 ptr -= len + 1; 2283 total_len += len + 1; 2284 if (ptr < name) { 2285 ret = -ENAMETOOLONG; 2286 goto out; 2287 } 2288 2289 *(ptr + len) = '/'; 2290 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len); 2291 2292 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 2293 break; 2294 2295 btrfs_release_path(path); 2296 key.objectid = key.offset; 2297 key.offset = (u64)-1; 2298 dirid = key.objectid; 2299 } 2300 memmove(name, ptr, total_len); 2301 name[total_len] = '\0'; 2302 ret = 0; 2303 out: 2304 btrfs_free_path(path); 2305 return ret; 2306 } 2307 2308 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 2309 void __user *argp) 2310 { 2311 struct btrfs_ioctl_ino_lookup_args *args; 2312 struct inode *inode; 2313 int ret; 2314 2315 if (!capable(CAP_SYS_ADMIN)) 2316 return -EPERM; 2317 2318 args = memdup_user(argp, sizeof(*args)); 2319 if (IS_ERR(args)) 2320 return PTR_ERR(args); 2321 2322 inode = file_inode(file); 2323 2324 if (args->treeid == 0) 2325 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 2326 2327 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 2328 args->treeid, args->objectid, 2329 args->name); 2330 2331 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 2332 ret = -EFAULT; 2333 2334 kfree(args); 2335 return ret; 2336 } 2337 2338 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 2339 void __user *arg) 2340 { 2341 struct dentry *parent = file->f_path.dentry; 2342 struct dentry *dentry; 2343 struct inode *dir = parent->d_inode; 2344 struct inode *inode; 2345 struct btrfs_root *root = BTRFS_I(dir)->root; 2346 struct btrfs_root *dest = NULL; 2347 struct btrfs_ioctl_vol_args *vol_args; 2348 struct btrfs_trans_handle *trans; 2349 struct btrfs_block_rsv block_rsv; 2350 u64 root_flags; 2351 u64 qgroup_reserved; 2352 int namelen; 2353 int ret; 2354 int err = 0; 2355 2356 vol_args = memdup_user(arg, sizeof(*vol_args)); 2357 if (IS_ERR(vol_args)) 2358 return PTR_ERR(vol_args); 2359 2360 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2361 namelen = strlen(vol_args->name); 2362 if (strchr(vol_args->name, '/') || 2363 strncmp(vol_args->name, "..", namelen) == 0) { 2364 err = -EINVAL; 2365 goto out; 2366 } 2367 2368 err = mnt_want_write_file(file); 2369 if (err) 2370 goto out; 2371 2372 2373 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT); 2374 if (err == -EINTR) 2375 goto out_drop_write; 2376 dentry = lookup_one_len(vol_args->name, parent, namelen); 2377 if (IS_ERR(dentry)) { 2378 err = PTR_ERR(dentry); 2379 goto out_unlock_dir; 2380 } 2381 2382 if (!dentry->d_inode) { 2383 err = -ENOENT; 2384 goto out_dput; 2385 } 2386 2387 inode = dentry->d_inode; 2388 dest = BTRFS_I(inode)->root; 2389 if (!capable(CAP_SYS_ADMIN)) { 2390 /* 2391 * Regular user. Only allow this with a special mount 2392 * option, when the user has write+exec access to the 2393 * subvol root, and when rmdir(2) would have been 2394 * allowed. 2395 * 2396 * Note that this is _not_ check that the subvol is 2397 * empty or doesn't contain data that we wouldn't 2398 * otherwise be able to delete. 2399 * 2400 * Users who want to delete empty subvols should try 2401 * rmdir(2). 2402 */ 2403 err = -EPERM; 2404 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 2405 goto out_dput; 2406 2407 /* 2408 * Do not allow deletion if the parent dir is the same 2409 * as the dir to be deleted. That means the ioctl 2410 * must be called on the dentry referencing the root 2411 * of the subvol, not a random directory contained 2412 * within it. 2413 */ 2414 err = -EINVAL; 2415 if (root == dest) 2416 goto out_dput; 2417 2418 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 2419 if (err) 2420 goto out_dput; 2421 } 2422 2423 /* check if subvolume may be deleted by a user */ 2424 err = btrfs_may_delete(dir, dentry, 1); 2425 if (err) 2426 goto out_dput; 2427 2428 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 2429 err = -EINVAL; 2430 goto out_dput; 2431 } 2432 2433 mutex_lock(&inode->i_mutex); 2434 2435 /* 2436 * Don't allow to delete a subvolume with send in progress. This is 2437 * inside the i_mutex so the error handling that has to drop the bit 2438 * again is not run concurrently. 2439 */ 2440 spin_lock(&dest->root_item_lock); 2441 root_flags = btrfs_root_flags(&dest->root_item); 2442 if (dest->send_in_progress == 0) { 2443 btrfs_set_root_flags(&dest->root_item, 2444 root_flags | BTRFS_ROOT_SUBVOL_DEAD); 2445 spin_unlock(&dest->root_item_lock); 2446 } else { 2447 spin_unlock(&dest->root_item_lock); 2448 btrfs_warn(root->fs_info, 2449 "Attempt to delete subvolume %llu during send", 2450 dest->root_key.objectid); 2451 err = -EPERM; 2452 goto out_dput; 2453 } 2454 2455 d_invalidate(dentry); 2456 2457 down_write(&root->fs_info->subvol_sem); 2458 2459 err = may_destroy_subvol(dest); 2460 if (err) 2461 goto out_up_write; 2462 2463 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); 2464 /* 2465 * One for dir inode, two for dir entries, two for root 2466 * ref/backref. 2467 */ 2468 err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 2469 5, &qgroup_reserved, true); 2470 if (err) 2471 goto out_up_write; 2472 2473 trans = btrfs_start_transaction(root, 0); 2474 if (IS_ERR(trans)) { 2475 err = PTR_ERR(trans); 2476 goto out_release; 2477 } 2478 trans->block_rsv = &block_rsv; 2479 trans->bytes_reserved = block_rsv.size; 2480 2481 ret = btrfs_unlink_subvol(trans, root, dir, 2482 dest->root_key.objectid, 2483 dentry->d_name.name, 2484 dentry->d_name.len); 2485 if (ret) { 2486 err = ret; 2487 btrfs_abort_transaction(trans, root, ret); 2488 goto out_end_trans; 2489 } 2490 2491 btrfs_record_root_in_trans(trans, dest); 2492 2493 memset(&dest->root_item.drop_progress, 0, 2494 sizeof(dest->root_item.drop_progress)); 2495 dest->root_item.drop_level = 0; 2496 btrfs_set_root_refs(&dest->root_item, 0); 2497 2498 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) { 2499 ret = btrfs_insert_orphan_item(trans, 2500 root->fs_info->tree_root, 2501 dest->root_key.objectid); 2502 if (ret) { 2503 btrfs_abort_transaction(trans, root, ret); 2504 err = ret; 2505 goto out_end_trans; 2506 } 2507 } 2508 2509 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, 2510 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL, 2511 dest->root_key.objectid); 2512 if (ret && ret != -ENOENT) { 2513 btrfs_abort_transaction(trans, root, ret); 2514 err = ret; 2515 goto out_end_trans; 2516 } 2517 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) { 2518 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, 2519 dest->root_item.received_uuid, 2520 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 2521 dest->root_key.objectid); 2522 if (ret && ret != -ENOENT) { 2523 btrfs_abort_transaction(trans, root, ret); 2524 err = ret; 2525 goto out_end_trans; 2526 } 2527 } 2528 2529 out_end_trans: 2530 trans->block_rsv = NULL; 2531 trans->bytes_reserved = 0; 2532 ret = btrfs_end_transaction(trans, root); 2533 if (ret && !err) 2534 err = ret; 2535 inode->i_flags |= S_DEAD; 2536 out_release: 2537 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); 2538 out_up_write: 2539 up_write(&root->fs_info->subvol_sem); 2540 if (err) { 2541 spin_lock(&dest->root_item_lock); 2542 root_flags = btrfs_root_flags(&dest->root_item); 2543 btrfs_set_root_flags(&dest->root_item, 2544 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD); 2545 spin_unlock(&dest->root_item_lock); 2546 } 2547 mutex_unlock(&inode->i_mutex); 2548 if (!err) { 2549 shrink_dcache_sb(root->fs_info->sb); 2550 btrfs_invalidate_inodes(dest); 2551 d_delete(dentry); 2552 ASSERT(dest->send_in_progress == 0); 2553 2554 /* the last ref */ 2555 if (dest->ino_cache_inode) { 2556 iput(dest->ino_cache_inode); 2557 dest->ino_cache_inode = NULL; 2558 } 2559 } 2560 out_dput: 2561 dput(dentry); 2562 out_unlock_dir: 2563 mutex_unlock(&dir->i_mutex); 2564 out_drop_write: 2565 mnt_drop_write_file(file); 2566 out: 2567 kfree(vol_args); 2568 return err; 2569 } 2570 2571 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 2572 { 2573 struct inode *inode = file_inode(file); 2574 struct btrfs_root *root = BTRFS_I(inode)->root; 2575 struct btrfs_ioctl_defrag_range_args *range; 2576 int ret; 2577 2578 ret = mnt_want_write_file(file); 2579 if (ret) 2580 return ret; 2581 2582 if (btrfs_root_readonly(root)) { 2583 ret = -EROFS; 2584 goto out; 2585 } 2586 2587 switch (inode->i_mode & S_IFMT) { 2588 case S_IFDIR: 2589 if (!capable(CAP_SYS_ADMIN)) { 2590 ret = -EPERM; 2591 goto out; 2592 } 2593 ret = btrfs_defrag_root(root); 2594 if (ret) 2595 goto out; 2596 ret = btrfs_defrag_root(root->fs_info->extent_root); 2597 break; 2598 case S_IFREG: 2599 if (!(file->f_mode & FMODE_WRITE)) { 2600 ret = -EINVAL; 2601 goto out; 2602 } 2603 2604 range = kzalloc(sizeof(*range), GFP_KERNEL); 2605 if (!range) { 2606 ret = -ENOMEM; 2607 goto out; 2608 } 2609 2610 if (argp) { 2611 if (copy_from_user(range, argp, 2612 sizeof(*range))) { 2613 ret = -EFAULT; 2614 kfree(range); 2615 goto out; 2616 } 2617 /* compression requires us to start the IO */ 2618 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2619 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2620 range->extent_thresh = (u32)-1; 2621 } 2622 } else { 2623 /* the rest are all set to zero by kzalloc */ 2624 range->len = (u64)-1; 2625 } 2626 ret = btrfs_defrag_file(file_inode(file), file, 2627 range, 0, 0); 2628 if (ret > 0) 2629 ret = 0; 2630 kfree(range); 2631 break; 2632 default: 2633 ret = -EINVAL; 2634 } 2635 out: 2636 mnt_drop_write_file(file); 2637 return ret; 2638 } 2639 2640 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) 2641 { 2642 struct btrfs_ioctl_vol_args *vol_args; 2643 int ret; 2644 2645 if (!capable(CAP_SYS_ADMIN)) 2646 return -EPERM; 2647 2648 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 2649 1)) { 2650 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 2651 } 2652 2653 mutex_lock(&root->fs_info->volume_mutex); 2654 vol_args = memdup_user(arg, sizeof(*vol_args)); 2655 if (IS_ERR(vol_args)) { 2656 ret = PTR_ERR(vol_args); 2657 goto out; 2658 } 2659 2660 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2661 ret = btrfs_init_new_device(root, vol_args->name); 2662 2663 if (!ret) 2664 btrfs_info(root->fs_info, "disk added %s",vol_args->name); 2665 2666 kfree(vol_args); 2667 out: 2668 mutex_unlock(&root->fs_info->volume_mutex); 2669 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 2670 return ret; 2671 } 2672 2673 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) 2674 { 2675 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 2676 struct btrfs_ioctl_vol_args *vol_args; 2677 int ret; 2678 2679 if (!capable(CAP_SYS_ADMIN)) 2680 return -EPERM; 2681 2682 ret = mnt_want_write_file(file); 2683 if (ret) 2684 return ret; 2685 2686 vol_args = memdup_user(arg, sizeof(*vol_args)); 2687 if (IS_ERR(vol_args)) { 2688 ret = PTR_ERR(vol_args); 2689 goto err_drop; 2690 } 2691 2692 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2693 2694 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 2695 1)) { 2696 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 2697 goto out; 2698 } 2699 2700 mutex_lock(&root->fs_info->volume_mutex); 2701 ret = btrfs_rm_device(root, vol_args->name); 2702 mutex_unlock(&root->fs_info->volume_mutex); 2703 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); 2704 2705 if (!ret) 2706 btrfs_info(root->fs_info, "disk deleted %s",vol_args->name); 2707 2708 out: 2709 kfree(vol_args); 2710 err_drop: 2711 mnt_drop_write_file(file); 2712 return ret; 2713 } 2714 2715 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) 2716 { 2717 struct btrfs_ioctl_fs_info_args *fi_args; 2718 struct btrfs_device *device; 2719 struct btrfs_device *next; 2720 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2721 int ret = 0; 2722 2723 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 2724 if (!fi_args) 2725 return -ENOMEM; 2726 2727 mutex_lock(&fs_devices->device_list_mutex); 2728 fi_args->num_devices = fs_devices->num_devices; 2729 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); 2730 2731 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 2732 if (device->devid > fi_args->max_id) 2733 fi_args->max_id = device->devid; 2734 } 2735 mutex_unlock(&fs_devices->device_list_mutex); 2736 2737 fi_args->nodesize = root->fs_info->super_copy->nodesize; 2738 fi_args->sectorsize = root->fs_info->super_copy->sectorsize; 2739 fi_args->clone_alignment = root->fs_info->super_copy->sectorsize; 2740 2741 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 2742 ret = -EFAULT; 2743 2744 kfree(fi_args); 2745 return ret; 2746 } 2747 2748 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) 2749 { 2750 struct btrfs_ioctl_dev_info_args *di_args; 2751 struct btrfs_device *dev; 2752 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 2753 int ret = 0; 2754 char *s_uuid = NULL; 2755 2756 di_args = memdup_user(arg, sizeof(*di_args)); 2757 if (IS_ERR(di_args)) 2758 return PTR_ERR(di_args); 2759 2760 if (!btrfs_is_empty_uuid(di_args->uuid)) 2761 s_uuid = di_args->uuid; 2762 2763 mutex_lock(&fs_devices->device_list_mutex); 2764 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL); 2765 2766 if (!dev) { 2767 ret = -ENODEV; 2768 goto out; 2769 } 2770 2771 di_args->devid = dev->devid; 2772 di_args->bytes_used = btrfs_device_get_bytes_used(dev); 2773 di_args->total_bytes = btrfs_device_get_total_bytes(dev); 2774 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 2775 if (dev->name) { 2776 struct rcu_string *name; 2777 2778 rcu_read_lock(); 2779 name = rcu_dereference(dev->name); 2780 strncpy(di_args->path, name->str, sizeof(di_args->path)); 2781 rcu_read_unlock(); 2782 di_args->path[sizeof(di_args->path) - 1] = 0; 2783 } else { 2784 di_args->path[0] = '\0'; 2785 } 2786 2787 out: 2788 mutex_unlock(&fs_devices->device_list_mutex); 2789 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 2790 ret = -EFAULT; 2791 2792 kfree(di_args); 2793 return ret; 2794 } 2795 2796 static struct page *extent_same_get_page(struct inode *inode, u64 off) 2797 { 2798 struct page *page; 2799 pgoff_t index; 2800 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree; 2801 2802 index = off >> PAGE_CACHE_SHIFT; 2803 2804 page = grab_cache_page(inode->i_mapping, index); 2805 if (!page) 2806 return NULL; 2807 2808 if (!PageUptodate(page)) { 2809 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent, 2810 0)) 2811 return NULL; 2812 lock_page(page); 2813 if (!PageUptodate(page)) { 2814 unlock_page(page); 2815 page_cache_release(page); 2816 return NULL; 2817 } 2818 } 2819 unlock_page(page); 2820 2821 return page; 2822 } 2823 2824 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len) 2825 { 2826 /* do any pending delalloc/csum calc on src, one way or 2827 another, and lock file content */ 2828 while (1) { 2829 struct btrfs_ordered_extent *ordered; 2830 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); 2831 ordered = btrfs_lookup_first_ordered_extent(inode, 2832 off + len - 1); 2833 if ((!ordered || 2834 ordered->file_offset + ordered->len <= off || 2835 ordered->file_offset >= off + len) && 2836 !test_range_bit(&BTRFS_I(inode)->io_tree, off, 2837 off + len - 1, EXTENT_DELALLOC, 0, NULL)) { 2838 if (ordered) 2839 btrfs_put_ordered_extent(ordered); 2840 break; 2841 } 2842 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); 2843 if (ordered) 2844 btrfs_put_ordered_extent(ordered); 2845 btrfs_wait_ordered_range(inode, off, len); 2846 } 2847 } 2848 2849 static void btrfs_double_unlock(struct inode *inode1, u64 loff1, 2850 struct inode *inode2, u64 loff2, u64 len) 2851 { 2852 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1); 2853 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1); 2854 2855 mutex_unlock(&inode1->i_mutex); 2856 mutex_unlock(&inode2->i_mutex); 2857 } 2858 2859 static void btrfs_double_lock(struct inode *inode1, u64 loff1, 2860 struct inode *inode2, u64 loff2, u64 len) 2861 { 2862 if (inode1 < inode2) { 2863 swap(inode1, inode2); 2864 swap(loff1, loff2); 2865 } 2866 2867 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT); 2868 lock_extent_range(inode1, loff1, len); 2869 if (inode1 != inode2) { 2870 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD); 2871 lock_extent_range(inode2, loff2, len); 2872 } 2873 } 2874 2875 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst, 2876 u64 dst_loff, u64 len) 2877 { 2878 int ret = 0; 2879 struct page *src_page, *dst_page; 2880 unsigned int cmp_len = PAGE_CACHE_SIZE; 2881 void *addr, *dst_addr; 2882 2883 while (len) { 2884 if (len < PAGE_CACHE_SIZE) 2885 cmp_len = len; 2886 2887 src_page = extent_same_get_page(src, loff); 2888 if (!src_page) 2889 return -EINVAL; 2890 dst_page = extent_same_get_page(dst, dst_loff); 2891 if (!dst_page) { 2892 page_cache_release(src_page); 2893 return -EINVAL; 2894 } 2895 addr = kmap_atomic(src_page); 2896 dst_addr = kmap_atomic(dst_page); 2897 2898 flush_dcache_page(src_page); 2899 flush_dcache_page(dst_page); 2900 2901 if (memcmp(addr, dst_addr, cmp_len)) 2902 ret = BTRFS_SAME_DATA_DIFFERS; 2903 2904 kunmap_atomic(addr); 2905 kunmap_atomic(dst_addr); 2906 page_cache_release(src_page); 2907 page_cache_release(dst_page); 2908 2909 if (ret) 2910 break; 2911 2912 loff += cmp_len; 2913 dst_loff += cmp_len; 2914 len -= cmp_len; 2915 } 2916 2917 return ret; 2918 } 2919 2920 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len) 2921 { 2922 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize; 2923 2924 if (off + len > inode->i_size || off + len < off) 2925 return -EINVAL; 2926 /* Check that we are block aligned - btrfs_clone() requires this */ 2927 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs)) 2928 return -EINVAL; 2929 2930 return 0; 2931 } 2932 2933 static int btrfs_extent_same(struct inode *src, u64 loff, u64 len, 2934 struct inode *dst, u64 dst_loff) 2935 { 2936 int ret; 2937 2938 /* 2939 * btrfs_clone() can't handle extents in the same file 2940 * yet. Once that works, we can drop this check and replace it 2941 * with a check for the same inode, but overlapping extents. 2942 */ 2943 if (src == dst) 2944 return -EINVAL; 2945 2946 btrfs_double_lock(src, loff, dst, dst_loff, len); 2947 2948 ret = extent_same_check_offsets(src, loff, len); 2949 if (ret) 2950 goto out_unlock; 2951 2952 ret = extent_same_check_offsets(dst, dst_loff, len); 2953 if (ret) 2954 goto out_unlock; 2955 2956 /* don't make the dst file partly checksummed */ 2957 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 2958 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) { 2959 ret = -EINVAL; 2960 goto out_unlock; 2961 } 2962 2963 ret = btrfs_cmp_data(src, loff, dst, dst_loff, len); 2964 if (ret == 0) 2965 ret = btrfs_clone(src, dst, loff, len, len, dst_loff); 2966 2967 out_unlock: 2968 btrfs_double_unlock(src, loff, dst, dst_loff, len); 2969 2970 return ret; 2971 } 2972 2973 #define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024) 2974 2975 static long btrfs_ioctl_file_extent_same(struct file *file, 2976 struct btrfs_ioctl_same_args __user *argp) 2977 { 2978 struct btrfs_ioctl_same_args *same; 2979 struct btrfs_ioctl_same_extent_info *info; 2980 struct inode *src = file_inode(file); 2981 u64 off; 2982 u64 len; 2983 int i; 2984 int ret; 2985 unsigned long size; 2986 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize; 2987 bool is_admin = capable(CAP_SYS_ADMIN); 2988 u16 count; 2989 2990 if (!(file->f_mode & FMODE_READ)) 2991 return -EINVAL; 2992 2993 ret = mnt_want_write_file(file); 2994 if (ret) 2995 return ret; 2996 2997 if (get_user(count, &argp->dest_count)) { 2998 ret = -EFAULT; 2999 goto out; 3000 } 3001 3002 size = offsetof(struct btrfs_ioctl_same_args __user, info[count]); 3003 3004 same = memdup_user(argp, size); 3005 3006 if (IS_ERR(same)) { 3007 ret = PTR_ERR(same); 3008 goto out; 3009 } 3010 3011 off = same->logical_offset; 3012 len = same->length; 3013 3014 /* 3015 * Limit the total length we will dedupe for each operation. 3016 * This is intended to bound the total time spent in this 3017 * ioctl to something sane. 3018 */ 3019 if (len > BTRFS_MAX_DEDUPE_LEN) 3020 len = BTRFS_MAX_DEDUPE_LEN; 3021 3022 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) { 3023 /* 3024 * Btrfs does not support blocksize < page_size. As a 3025 * result, btrfs_cmp_data() won't correctly handle 3026 * this situation without an update. 3027 */ 3028 ret = -EINVAL; 3029 goto out; 3030 } 3031 3032 ret = -EISDIR; 3033 if (S_ISDIR(src->i_mode)) 3034 goto out; 3035 3036 ret = -EACCES; 3037 if (!S_ISREG(src->i_mode)) 3038 goto out; 3039 3040 /* pre-format output fields to sane values */ 3041 for (i = 0; i < count; i++) { 3042 same->info[i].bytes_deduped = 0ULL; 3043 same->info[i].status = 0; 3044 } 3045 3046 for (i = 0, info = same->info; i < count; i++, info++) { 3047 struct inode *dst; 3048 struct fd dst_file = fdget(info->fd); 3049 if (!dst_file.file) { 3050 info->status = -EBADF; 3051 continue; 3052 } 3053 dst = file_inode(dst_file.file); 3054 3055 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) { 3056 info->status = -EINVAL; 3057 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) { 3058 info->status = -EXDEV; 3059 } else if (S_ISDIR(dst->i_mode)) { 3060 info->status = -EISDIR; 3061 } else if (!S_ISREG(dst->i_mode)) { 3062 info->status = -EACCES; 3063 } else { 3064 info->status = btrfs_extent_same(src, off, len, dst, 3065 info->logical_offset); 3066 if (info->status == 0) 3067 info->bytes_deduped += len; 3068 } 3069 fdput(dst_file); 3070 } 3071 3072 ret = copy_to_user(argp, same, size); 3073 if (ret) 3074 ret = -EFAULT; 3075 3076 out: 3077 mnt_drop_write_file(file); 3078 return ret; 3079 } 3080 3081 /* Helper to check and see if this root currently has a ref on the given disk 3082 * bytenr. If it does then we need to update the quota for this root. This 3083 * doesn't do anything if quotas aren't enabled. 3084 */ 3085 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, 3086 u64 disko) 3087 { 3088 struct seq_list tree_mod_seq_elem = {}; 3089 struct ulist *roots; 3090 struct ulist_iterator uiter; 3091 struct ulist_node *root_node = NULL; 3092 int ret; 3093 3094 if (!root->fs_info->quota_enabled) 3095 return 1; 3096 3097 btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem); 3098 ret = btrfs_find_all_roots(trans, root->fs_info, disko, 3099 tree_mod_seq_elem.seq, &roots); 3100 if (ret < 0) 3101 goto out; 3102 ret = 0; 3103 ULIST_ITER_INIT(&uiter); 3104 while ((root_node = ulist_next(roots, &uiter))) { 3105 if (root_node->val == root->objectid) { 3106 ret = 1; 3107 break; 3108 } 3109 } 3110 ulist_free(roots); 3111 out: 3112 btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem); 3113 return ret; 3114 } 3115 3116 static int clone_finish_inode_update(struct btrfs_trans_handle *trans, 3117 struct inode *inode, 3118 u64 endoff, 3119 const u64 destoff, 3120 const u64 olen) 3121 { 3122 struct btrfs_root *root = BTRFS_I(inode)->root; 3123 int ret; 3124 3125 inode_inc_iversion(inode); 3126 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 3127 /* 3128 * We round up to the block size at eof when determining which 3129 * extents to clone above, but shouldn't round up the file size. 3130 */ 3131 if (endoff > destoff + olen) 3132 endoff = destoff + olen; 3133 if (endoff > inode->i_size) 3134 btrfs_i_size_write(inode, endoff); 3135 3136 ret = btrfs_update_inode(trans, root, inode); 3137 if (ret) { 3138 btrfs_abort_transaction(trans, root, ret); 3139 btrfs_end_transaction(trans, root); 3140 goto out; 3141 } 3142 ret = btrfs_end_transaction(trans, root); 3143 out: 3144 return ret; 3145 } 3146 3147 static void clone_update_extent_map(struct inode *inode, 3148 const struct btrfs_trans_handle *trans, 3149 const struct btrfs_path *path, 3150 const u64 hole_offset, 3151 const u64 hole_len) 3152 { 3153 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 3154 struct extent_map *em; 3155 int ret; 3156 3157 em = alloc_extent_map(); 3158 if (!em) { 3159 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3160 &BTRFS_I(inode)->runtime_flags); 3161 return; 3162 } 3163 3164 if (path) { 3165 struct btrfs_file_extent_item *fi; 3166 3167 fi = btrfs_item_ptr(path->nodes[0], path->slots[0], 3168 struct btrfs_file_extent_item); 3169 btrfs_extent_item_to_extent_map(inode, path, fi, false, em); 3170 em->generation = -1; 3171 if (btrfs_file_extent_type(path->nodes[0], fi) == 3172 BTRFS_FILE_EXTENT_INLINE) 3173 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3174 &BTRFS_I(inode)->runtime_flags); 3175 } else { 3176 em->start = hole_offset; 3177 em->len = hole_len; 3178 em->ram_bytes = em->len; 3179 em->orig_start = hole_offset; 3180 em->block_start = EXTENT_MAP_HOLE; 3181 em->block_len = 0; 3182 em->orig_block_len = 0; 3183 em->compress_type = BTRFS_COMPRESS_NONE; 3184 em->generation = trans->transid; 3185 } 3186 3187 while (1) { 3188 write_lock(&em_tree->lock); 3189 ret = add_extent_mapping(em_tree, em, 1); 3190 write_unlock(&em_tree->lock); 3191 if (ret != -EEXIST) { 3192 free_extent_map(em); 3193 break; 3194 } 3195 btrfs_drop_extent_cache(inode, em->start, 3196 em->start + em->len - 1, 0); 3197 } 3198 3199 if (ret) 3200 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3201 &BTRFS_I(inode)->runtime_flags); 3202 } 3203 3204 /** 3205 * btrfs_clone() - clone a range from inode file to another 3206 * 3207 * @src: Inode to clone from 3208 * @inode: Inode to clone to 3209 * @off: Offset within source to start clone from 3210 * @olen: Original length, passed by user, of range to clone 3211 * @olen_aligned: Block-aligned value of olen, extent_same uses 3212 * identical values here 3213 * @destoff: Offset within @inode to start clone 3214 */ 3215 static int btrfs_clone(struct inode *src, struct inode *inode, 3216 const u64 off, const u64 olen, const u64 olen_aligned, 3217 const u64 destoff) 3218 { 3219 struct btrfs_root *root = BTRFS_I(inode)->root; 3220 struct btrfs_path *path = NULL; 3221 struct extent_buffer *leaf; 3222 struct btrfs_trans_handle *trans; 3223 char *buf = NULL; 3224 struct btrfs_key key; 3225 u32 nritems; 3226 int slot; 3227 int ret; 3228 int no_quota; 3229 const u64 len = olen_aligned; 3230 u64 last_disko = 0; 3231 u64 last_dest_end = destoff; 3232 3233 ret = -ENOMEM; 3234 buf = vmalloc(root->nodesize); 3235 if (!buf) 3236 return ret; 3237 3238 path = btrfs_alloc_path(); 3239 if (!path) { 3240 vfree(buf); 3241 return ret; 3242 } 3243 3244 path->reada = 2; 3245 /* clone data */ 3246 key.objectid = btrfs_ino(src); 3247 key.type = BTRFS_EXTENT_DATA_KEY; 3248 key.offset = off; 3249 3250 while (1) { 3251 /* 3252 * note the key will change type as we walk through the 3253 * tree. 3254 */ 3255 path->leave_spinning = 1; 3256 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path, 3257 0, 0); 3258 if (ret < 0) 3259 goto out; 3260 /* 3261 * First search, if no extent item that starts at offset off was 3262 * found but the previous item is an extent item, it's possible 3263 * it might overlap our target range, therefore process it. 3264 */ 3265 if (key.offset == off && ret > 0 && path->slots[0] > 0) { 3266 btrfs_item_key_to_cpu(path->nodes[0], &key, 3267 path->slots[0] - 1); 3268 if (key.type == BTRFS_EXTENT_DATA_KEY) 3269 path->slots[0]--; 3270 } 3271 3272 nritems = btrfs_header_nritems(path->nodes[0]); 3273 process_slot: 3274 no_quota = 1; 3275 if (path->slots[0] >= nritems) { 3276 ret = btrfs_next_leaf(BTRFS_I(src)->root, path); 3277 if (ret < 0) 3278 goto out; 3279 if (ret > 0) 3280 break; 3281 nritems = btrfs_header_nritems(path->nodes[0]); 3282 } 3283 leaf = path->nodes[0]; 3284 slot = path->slots[0]; 3285 3286 btrfs_item_key_to_cpu(leaf, &key, slot); 3287 if (key.type > BTRFS_EXTENT_DATA_KEY || 3288 key.objectid != btrfs_ino(src)) 3289 break; 3290 3291 if (key.type == BTRFS_EXTENT_DATA_KEY) { 3292 struct btrfs_file_extent_item *extent; 3293 int type; 3294 u32 size; 3295 struct btrfs_key new_key; 3296 u64 disko = 0, diskl = 0; 3297 u64 datao = 0, datal = 0; 3298 u8 comp; 3299 u64 drop_start; 3300 3301 extent = btrfs_item_ptr(leaf, slot, 3302 struct btrfs_file_extent_item); 3303 comp = btrfs_file_extent_compression(leaf, extent); 3304 type = btrfs_file_extent_type(leaf, extent); 3305 if (type == BTRFS_FILE_EXTENT_REG || 3306 type == BTRFS_FILE_EXTENT_PREALLOC) { 3307 disko = btrfs_file_extent_disk_bytenr(leaf, 3308 extent); 3309 diskl = btrfs_file_extent_disk_num_bytes(leaf, 3310 extent); 3311 datao = btrfs_file_extent_offset(leaf, extent); 3312 datal = btrfs_file_extent_num_bytes(leaf, 3313 extent); 3314 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 3315 /* take upper bound, may be compressed */ 3316 datal = btrfs_file_extent_ram_bytes(leaf, 3317 extent); 3318 } 3319 3320 /* 3321 * The first search might have left us at an extent 3322 * item that ends before our target range's start, can 3323 * happen if we have holes and NO_HOLES feature enabled. 3324 */ 3325 if (key.offset + datal <= off) { 3326 path->slots[0]++; 3327 goto process_slot; 3328 } else if (key.offset >= off + len) { 3329 break; 3330 } 3331 3332 size = btrfs_item_size_nr(leaf, slot); 3333 read_extent_buffer(leaf, buf, 3334 btrfs_item_ptr_offset(leaf, slot), 3335 size); 3336 3337 btrfs_release_path(path); 3338 path->leave_spinning = 0; 3339 3340 memcpy(&new_key, &key, sizeof(new_key)); 3341 new_key.objectid = btrfs_ino(inode); 3342 if (off <= key.offset) 3343 new_key.offset = key.offset + destoff - off; 3344 else 3345 new_key.offset = destoff; 3346 3347 /* 3348 * Deal with a hole that doesn't have an extent item 3349 * that represents it (NO_HOLES feature enabled). 3350 * This hole is either in the middle of the cloning 3351 * range or at the beginning (fully overlaps it or 3352 * partially overlaps it). 3353 */ 3354 if (new_key.offset != last_dest_end) 3355 drop_start = last_dest_end; 3356 else 3357 drop_start = new_key.offset; 3358 3359 /* 3360 * 1 - adjusting old extent (we may have to split it) 3361 * 1 - add new extent 3362 * 1 - inode update 3363 */ 3364 trans = btrfs_start_transaction(root, 3); 3365 if (IS_ERR(trans)) { 3366 ret = PTR_ERR(trans); 3367 goto out; 3368 } 3369 3370 if (type == BTRFS_FILE_EXTENT_REG || 3371 type == BTRFS_FILE_EXTENT_PREALLOC) { 3372 /* 3373 * a | --- range to clone ---| b 3374 * | ------------- extent ------------- | 3375 */ 3376 3377 /* subtract range b */ 3378 if (key.offset + datal > off + len) 3379 datal = off + len - key.offset; 3380 3381 /* subtract range a */ 3382 if (off > key.offset) { 3383 datao += off - key.offset; 3384 datal -= off - key.offset; 3385 } 3386 3387 ret = btrfs_drop_extents(trans, root, inode, 3388 drop_start, 3389 new_key.offset + datal, 3390 1); 3391 if (ret) { 3392 if (ret != -EOPNOTSUPP) 3393 btrfs_abort_transaction(trans, 3394 root, ret); 3395 btrfs_end_transaction(trans, root); 3396 goto out; 3397 } 3398 3399 ret = btrfs_insert_empty_item(trans, root, path, 3400 &new_key, size); 3401 if (ret) { 3402 btrfs_abort_transaction(trans, root, 3403 ret); 3404 btrfs_end_transaction(trans, root); 3405 goto out; 3406 } 3407 3408 leaf = path->nodes[0]; 3409 slot = path->slots[0]; 3410 write_extent_buffer(leaf, buf, 3411 btrfs_item_ptr_offset(leaf, slot), 3412 size); 3413 3414 extent = btrfs_item_ptr(leaf, slot, 3415 struct btrfs_file_extent_item); 3416 3417 /* disko == 0 means it's a hole */ 3418 if (!disko) 3419 datao = 0; 3420 3421 btrfs_set_file_extent_offset(leaf, extent, 3422 datao); 3423 btrfs_set_file_extent_num_bytes(leaf, extent, 3424 datal); 3425 3426 /* 3427 * We need to look up the roots that point at 3428 * this bytenr and see if the new root does. If 3429 * it does not we need to make sure we update 3430 * quotas appropriately. 3431 */ 3432 if (disko && root != BTRFS_I(src)->root && 3433 disko != last_disko) { 3434 no_quota = check_ref(trans, root, 3435 disko); 3436 if (no_quota < 0) { 3437 btrfs_abort_transaction(trans, 3438 root, 3439 ret); 3440 btrfs_end_transaction(trans, 3441 root); 3442 ret = no_quota; 3443 goto out; 3444 } 3445 } 3446 3447 if (disko) { 3448 inode_add_bytes(inode, datal); 3449 ret = btrfs_inc_extent_ref(trans, root, 3450 disko, diskl, 0, 3451 root->root_key.objectid, 3452 btrfs_ino(inode), 3453 new_key.offset - datao, 3454 no_quota); 3455 if (ret) { 3456 btrfs_abort_transaction(trans, 3457 root, 3458 ret); 3459 btrfs_end_transaction(trans, 3460 root); 3461 goto out; 3462 3463 } 3464 } 3465 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 3466 u64 skip = 0; 3467 u64 trim = 0; 3468 u64 aligned_end = 0; 3469 3470 if (off > key.offset) { 3471 skip = off - key.offset; 3472 new_key.offset += skip; 3473 } 3474 3475 if (key.offset + datal > off + len) 3476 trim = key.offset + datal - (off + len); 3477 3478 if (comp && (skip || trim)) { 3479 ret = -EINVAL; 3480 btrfs_end_transaction(trans, root); 3481 goto out; 3482 } 3483 size -= skip + trim; 3484 datal -= skip + trim; 3485 3486 aligned_end = ALIGN(new_key.offset + datal, 3487 root->sectorsize); 3488 ret = btrfs_drop_extents(trans, root, inode, 3489 drop_start, 3490 aligned_end, 3491 1); 3492 if (ret) { 3493 if (ret != -EOPNOTSUPP) 3494 btrfs_abort_transaction(trans, 3495 root, ret); 3496 btrfs_end_transaction(trans, root); 3497 goto out; 3498 } 3499 3500 ret = btrfs_insert_empty_item(trans, root, path, 3501 &new_key, size); 3502 if (ret) { 3503 btrfs_abort_transaction(trans, root, 3504 ret); 3505 btrfs_end_transaction(trans, root); 3506 goto out; 3507 } 3508 3509 if (skip) { 3510 u32 start = 3511 btrfs_file_extent_calc_inline_size(0); 3512 memmove(buf+start, buf+start+skip, 3513 datal); 3514 } 3515 3516 leaf = path->nodes[0]; 3517 slot = path->slots[0]; 3518 write_extent_buffer(leaf, buf, 3519 btrfs_item_ptr_offset(leaf, slot), 3520 size); 3521 inode_add_bytes(inode, datal); 3522 } 3523 3524 /* If we have an implicit hole (NO_HOLES feature). */ 3525 if (drop_start < new_key.offset) 3526 clone_update_extent_map(inode, trans, 3527 NULL, drop_start, 3528 new_key.offset - drop_start); 3529 3530 clone_update_extent_map(inode, trans, path, 0, 0); 3531 3532 btrfs_mark_buffer_dirty(leaf); 3533 btrfs_release_path(path); 3534 3535 last_dest_end = ALIGN(new_key.offset + datal, 3536 root->sectorsize); 3537 ret = clone_finish_inode_update(trans, inode, 3538 last_dest_end, 3539 destoff, olen); 3540 if (ret) 3541 goto out; 3542 if (new_key.offset + datal >= destoff + len) 3543 break; 3544 } 3545 btrfs_release_path(path); 3546 key.offset++; 3547 } 3548 ret = 0; 3549 3550 if (last_dest_end < destoff + len) { 3551 /* 3552 * We have an implicit hole (NO_HOLES feature is enabled) that 3553 * fully or partially overlaps our cloning range at its end. 3554 */ 3555 btrfs_release_path(path); 3556 3557 /* 3558 * 1 - remove extent(s) 3559 * 1 - inode update 3560 */ 3561 trans = btrfs_start_transaction(root, 2); 3562 if (IS_ERR(trans)) { 3563 ret = PTR_ERR(trans); 3564 goto out; 3565 } 3566 ret = btrfs_drop_extents(trans, root, inode, 3567 last_dest_end, destoff + len, 1); 3568 if (ret) { 3569 if (ret != -EOPNOTSUPP) 3570 btrfs_abort_transaction(trans, root, ret); 3571 btrfs_end_transaction(trans, root); 3572 goto out; 3573 } 3574 clone_update_extent_map(inode, trans, NULL, last_dest_end, 3575 destoff + len - last_dest_end); 3576 ret = clone_finish_inode_update(trans, inode, destoff + len, 3577 destoff, olen); 3578 } 3579 3580 out: 3581 btrfs_free_path(path); 3582 vfree(buf); 3583 return ret; 3584 } 3585 3586 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, 3587 u64 off, u64 olen, u64 destoff) 3588 { 3589 struct inode *inode = file_inode(file); 3590 struct btrfs_root *root = BTRFS_I(inode)->root; 3591 struct fd src_file; 3592 struct inode *src; 3593 int ret; 3594 u64 len = olen; 3595 u64 bs = root->fs_info->sb->s_blocksize; 3596 int same_inode = 0; 3597 3598 /* 3599 * TODO: 3600 * - split compressed inline extents. annoying: we need to 3601 * decompress into destination's address_space (the file offset 3602 * may change, so source mapping won't do), then recompress (or 3603 * otherwise reinsert) a subrange. 3604 * 3605 * - split destination inode's inline extents. The inline extents can 3606 * be either compressed or non-compressed. 3607 */ 3608 3609 /* the destination must be opened for writing */ 3610 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) 3611 return -EINVAL; 3612 3613 if (btrfs_root_readonly(root)) 3614 return -EROFS; 3615 3616 ret = mnt_want_write_file(file); 3617 if (ret) 3618 return ret; 3619 3620 src_file = fdget(srcfd); 3621 if (!src_file.file) { 3622 ret = -EBADF; 3623 goto out_drop_write; 3624 } 3625 3626 ret = -EXDEV; 3627 if (src_file.file->f_path.mnt != file->f_path.mnt) 3628 goto out_fput; 3629 3630 src = file_inode(src_file.file); 3631 3632 ret = -EINVAL; 3633 if (src == inode) 3634 same_inode = 1; 3635 3636 /* the src must be open for reading */ 3637 if (!(src_file.file->f_mode & FMODE_READ)) 3638 goto out_fput; 3639 3640 /* don't make the dst file partly checksummed */ 3641 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 3642 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) 3643 goto out_fput; 3644 3645 ret = -EISDIR; 3646 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 3647 goto out_fput; 3648 3649 ret = -EXDEV; 3650 if (src->i_sb != inode->i_sb) 3651 goto out_fput; 3652 3653 if (!same_inode) { 3654 if (inode < src) { 3655 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); 3656 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); 3657 } else { 3658 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); 3659 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); 3660 } 3661 } else { 3662 mutex_lock(&src->i_mutex); 3663 } 3664 3665 /* determine range to clone */ 3666 ret = -EINVAL; 3667 if (off + len > src->i_size || off + len < off) 3668 goto out_unlock; 3669 if (len == 0) 3670 olen = len = src->i_size - off; 3671 /* if we extend to eof, continue to block boundary */ 3672 if (off + len == src->i_size) 3673 len = ALIGN(src->i_size, bs) - off; 3674 3675 /* verify the end result is block aligned */ 3676 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || 3677 !IS_ALIGNED(destoff, bs)) 3678 goto out_unlock; 3679 3680 /* verify if ranges are overlapped within the same file */ 3681 if (same_inode) { 3682 if (destoff + len > off && destoff < off + len) 3683 goto out_unlock; 3684 } 3685 3686 if (destoff > inode->i_size) { 3687 ret = btrfs_cont_expand(inode, inode->i_size, destoff); 3688 if (ret) 3689 goto out_unlock; 3690 } 3691 3692 /* 3693 * Lock the target range too. Right after we replace the file extent 3694 * items in the fs tree (which now point to the cloned data), we might 3695 * have a worker replace them with extent items relative to a write 3696 * operation that was issued before this clone operation (i.e. confront 3697 * with inode.c:btrfs_finish_ordered_io). 3698 */ 3699 if (same_inode) { 3700 u64 lock_start = min_t(u64, off, destoff); 3701 u64 lock_len = max_t(u64, off, destoff) + len - lock_start; 3702 3703 lock_extent_range(src, lock_start, lock_len); 3704 } else { 3705 lock_extent_range(src, off, len); 3706 lock_extent_range(inode, destoff, len); 3707 } 3708 3709 ret = btrfs_clone(src, inode, off, olen, len, destoff); 3710 3711 if (same_inode) { 3712 u64 lock_start = min_t(u64, off, destoff); 3713 u64 lock_end = max_t(u64, off, destoff) + len - 1; 3714 3715 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end); 3716 } else { 3717 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); 3718 unlock_extent(&BTRFS_I(inode)->io_tree, destoff, 3719 destoff + len - 1); 3720 } 3721 /* 3722 * Truncate page cache pages so that future reads will see the cloned 3723 * data immediately and not the previous data. 3724 */ 3725 truncate_inode_pages_range(&inode->i_data, destoff, 3726 PAGE_CACHE_ALIGN(destoff + len) - 1); 3727 out_unlock: 3728 if (!same_inode) { 3729 if (inode < src) { 3730 mutex_unlock(&src->i_mutex); 3731 mutex_unlock(&inode->i_mutex); 3732 } else { 3733 mutex_unlock(&inode->i_mutex); 3734 mutex_unlock(&src->i_mutex); 3735 } 3736 } else { 3737 mutex_unlock(&src->i_mutex); 3738 } 3739 out_fput: 3740 fdput(src_file); 3741 out_drop_write: 3742 mnt_drop_write_file(file); 3743 return ret; 3744 } 3745 3746 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) 3747 { 3748 struct btrfs_ioctl_clone_range_args args; 3749 3750 if (copy_from_user(&args, argp, sizeof(args))) 3751 return -EFAULT; 3752 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, 3753 args.src_length, args.dest_offset); 3754 } 3755 3756 /* 3757 * there are many ways the trans_start and trans_end ioctls can lead 3758 * to deadlocks. They should only be used by applications that 3759 * basically own the machine, and have a very in depth understanding 3760 * of all the possible deadlocks and enospc problems. 3761 */ 3762 static long btrfs_ioctl_trans_start(struct file *file) 3763 { 3764 struct inode *inode = file_inode(file); 3765 struct btrfs_root *root = BTRFS_I(inode)->root; 3766 struct btrfs_trans_handle *trans; 3767 int ret; 3768 3769 ret = -EPERM; 3770 if (!capable(CAP_SYS_ADMIN)) 3771 goto out; 3772 3773 ret = -EINPROGRESS; 3774 if (file->private_data) 3775 goto out; 3776 3777 ret = -EROFS; 3778 if (btrfs_root_readonly(root)) 3779 goto out; 3780 3781 ret = mnt_want_write_file(file); 3782 if (ret) 3783 goto out; 3784 3785 atomic_inc(&root->fs_info->open_ioctl_trans); 3786 3787 ret = -ENOMEM; 3788 trans = btrfs_start_ioctl_transaction(root); 3789 if (IS_ERR(trans)) 3790 goto out_drop; 3791 3792 file->private_data = trans; 3793 return 0; 3794 3795 out_drop: 3796 atomic_dec(&root->fs_info->open_ioctl_trans); 3797 mnt_drop_write_file(file); 3798 out: 3799 return ret; 3800 } 3801 3802 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) 3803 { 3804 struct inode *inode = file_inode(file); 3805 struct btrfs_root *root = BTRFS_I(inode)->root; 3806 struct btrfs_root *new_root; 3807 struct btrfs_dir_item *di; 3808 struct btrfs_trans_handle *trans; 3809 struct btrfs_path *path; 3810 struct btrfs_key location; 3811 struct btrfs_disk_key disk_key; 3812 u64 objectid = 0; 3813 u64 dir_id; 3814 int ret; 3815 3816 if (!capable(CAP_SYS_ADMIN)) 3817 return -EPERM; 3818 3819 ret = mnt_want_write_file(file); 3820 if (ret) 3821 return ret; 3822 3823 if (copy_from_user(&objectid, argp, sizeof(objectid))) { 3824 ret = -EFAULT; 3825 goto out; 3826 } 3827 3828 if (!objectid) 3829 objectid = BTRFS_FS_TREE_OBJECTID; 3830 3831 location.objectid = objectid; 3832 location.type = BTRFS_ROOT_ITEM_KEY; 3833 location.offset = (u64)-1; 3834 3835 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); 3836 if (IS_ERR(new_root)) { 3837 ret = PTR_ERR(new_root); 3838 goto out; 3839 } 3840 3841 path = btrfs_alloc_path(); 3842 if (!path) { 3843 ret = -ENOMEM; 3844 goto out; 3845 } 3846 path->leave_spinning = 1; 3847 3848 trans = btrfs_start_transaction(root, 1); 3849 if (IS_ERR(trans)) { 3850 btrfs_free_path(path); 3851 ret = PTR_ERR(trans); 3852 goto out; 3853 } 3854 3855 dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 3856 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, 3857 dir_id, "default", 7, 1); 3858 if (IS_ERR_OR_NULL(di)) { 3859 btrfs_free_path(path); 3860 btrfs_end_transaction(trans, root); 3861 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir" 3862 "item, this isn't going to work"); 3863 ret = -ENOENT; 3864 goto out; 3865 } 3866 3867 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); 3868 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); 3869 btrfs_mark_buffer_dirty(path->nodes[0]); 3870 btrfs_free_path(path); 3871 3872 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL); 3873 btrfs_end_transaction(trans, root); 3874 out: 3875 mnt_drop_write_file(file); 3876 return ret; 3877 } 3878 3879 void btrfs_get_block_group_info(struct list_head *groups_list, 3880 struct btrfs_ioctl_space_info *space) 3881 { 3882 struct btrfs_block_group_cache *block_group; 3883 3884 space->total_bytes = 0; 3885 space->used_bytes = 0; 3886 space->flags = 0; 3887 list_for_each_entry(block_group, groups_list, list) { 3888 space->flags = block_group->flags; 3889 space->total_bytes += block_group->key.offset; 3890 space->used_bytes += 3891 btrfs_block_group_used(&block_group->item); 3892 } 3893 } 3894 3895 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) 3896 { 3897 struct btrfs_ioctl_space_args space_args; 3898 struct btrfs_ioctl_space_info space; 3899 struct btrfs_ioctl_space_info *dest; 3900 struct btrfs_ioctl_space_info *dest_orig; 3901 struct btrfs_ioctl_space_info __user *user_dest; 3902 struct btrfs_space_info *info; 3903 u64 types[] = {BTRFS_BLOCK_GROUP_DATA, 3904 BTRFS_BLOCK_GROUP_SYSTEM, 3905 BTRFS_BLOCK_GROUP_METADATA, 3906 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; 3907 int num_types = 4; 3908 int alloc_size; 3909 int ret = 0; 3910 u64 slot_count = 0; 3911 int i, c; 3912 3913 if (copy_from_user(&space_args, 3914 (struct btrfs_ioctl_space_args __user *)arg, 3915 sizeof(space_args))) 3916 return -EFAULT; 3917 3918 for (i = 0; i < num_types; i++) { 3919 struct btrfs_space_info *tmp; 3920 3921 info = NULL; 3922 rcu_read_lock(); 3923 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 3924 list) { 3925 if (tmp->flags == types[i]) { 3926 info = tmp; 3927 break; 3928 } 3929 } 3930 rcu_read_unlock(); 3931 3932 if (!info) 3933 continue; 3934 3935 down_read(&info->groups_sem); 3936 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 3937 if (!list_empty(&info->block_groups[c])) 3938 slot_count++; 3939 } 3940 up_read(&info->groups_sem); 3941 } 3942 3943 /* 3944 * Global block reserve, exported as a space_info 3945 */ 3946 slot_count++; 3947 3948 /* space_slots == 0 means they are asking for a count */ 3949 if (space_args.space_slots == 0) { 3950 space_args.total_spaces = slot_count; 3951 goto out; 3952 } 3953 3954 slot_count = min_t(u64, space_args.space_slots, slot_count); 3955 3956 alloc_size = sizeof(*dest) * slot_count; 3957 3958 /* we generally have at most 6 or so space infos, one for each raid 3959 * level. So, a whole page should be more than enough for everyone 3960 */ 3961 if (alloc_size > PAGE_CACHE_SIZE) 3962 return -ENOMEM; 3963 3964 space_args.total_spaces = 0; 3965 dest = kmalloc(alloc_size, GFP_NOFS); 3966 if (!dest) 3967 return -ENOMEM; 3968 dest_orig = dest; 3969 3970 /* now we have a buffer to copy into */ 3971 for (i = 0; i < num_types; i++) { 3972 struct btrfs_space_info *tmp; 3973 3974 if (!slot_count) 3975 break; 3976 3977 info = NULL; 3978 rcu_read_lock(); 3979 list_for_each_entry_rcu(tmp, &root->fs_info->space_info, 3980 list) { 3981 if (tmp->flags == types[i]) { 3982 info = tmp; 3983 break; 3984 } 3985 } 3986 rcu_read_unlock(); 3987 3988 if (!info) 3989 continue; 3990 down_read(&info->groups_sem); 3991 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 3992 if (!list_empty(&info->block_groups[c])) { 3993 btrfs_get_block_group_info( 3994 &info->block_groups[c], &space); 3995 memcpy(dest, &space, sizeof(space)); 3996 dest++; 3997 space_args.total_spaces++; 3998 slot_count--; 3999 } 4000 if (!slot_count) 4001 break; 4002 } 4003 up_read(&info->groups_sem); 4004 } 4005 4006 /* 4007 * Add global block reserve 4008 */ 4009 if (slot_count) { 4010 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv; 4011 4012 spin_lock(&block_rsv->lock); 4013 space.total_bytes = block_rsv->size; 4014 space.used_bytes = block_rsv->size - block_rsv->reserved; 4015 spin_unlock(&block_rsv->lock); 4016 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV; 4017 memcpy(dest, &space, sizeof(space)); 4018 space_args.total_spaces++; 4019 } 4020 4021 user_dest = (struct btrfs_ioctl_space_info __user *) 4022 (arg + sizeof(struct btrfs_ioctl_space_args)); 4023 4024 if (copy_to_user(user_dest, dest_orig, alloc_size)) 4025 ret = -EFAULT; 4026 4027 kfree(dest_orig); 4028 out: 4029 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) 4030 ret = -EFAULT; 4031 4032 return ret; 4033 } 4034 4035 /* 4036 * there are many ways the trans_start and trans_end ioctls can lead 4037 * to deadlocks. They should only be used by applications that 4038 * basically own the machine, and have a very in depth understanding 4039 * of all the possible deadlocks and enospc problems. 4040 */ 4041 long btrfs_ioctl_trans_end(struct file *file) 4042 { 4043 struct inode *inode = file_inode(file); 4044 struct btrfs_root *root = BTRFS_I(inode)->root; 4045 struct btrfs_trans_handle *trans; 4046 4047 trans = file->private_data; 4048 if (!trans) 4049 return -EINVAL; 4050 file->private_data = NULL; 4051 4052 btrfs_end_transaction(trans, root); 4053 4054 atomic_dec(&root->fs_info->open_ioctl_trans); 4055 4056 mnt_drop_write_file(file); 4057 return 0; 4058 } 4059 4060 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root, 4061 void __user *argp) 4062 { 4063 struct btrfs_trans_handle *trans; 4064 u64 transid; 4065 int ret; 4066 4067 trans = btrfs_attach_transaction_barrier(root); 4068 if (IS_ERR(trans)) { 4069 if (PTR_ERR(trans) != -ENOENT) 4070 return PTR_ERR(trans); 4071 4072 /* No running transaction, don't bother */ 4073 transid = root->fs_info->last_trans_committed; 4074 goto out; 4075 } 4076 transid = trans->transid; 4077 ret = btrfs_commit_transaction_async(trans, root, 0); 4078 if (ret) { 4079 btrfs_end_transaction(trans, root); 4080 return ret; 4081 } 4082 out: 4083 if (argp) 4084 if (copy_to_user(argp, &transid, sizeof(transid))) 4085 return -EFAULT; 4086 return 0; 4087 } 4088 4089 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root, 4090 void __user *argp) 4091 { 4092 u64 transid; 4093 4094 if (argp) { 4095 if (copy_from_user(&transid, argp, sizeof(transid))) 4096 return -EFAULT; 4097 } else { 4098 transid = 0; /* current trans */ 4099 } 4100 return btrfs_wait_for_commit(root, transid); 4101 } 4102 4103 static long btrfs_ioctl_scrub(struct file *file, void __user *arg) 4104 { 4105 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4106 struct btrfs_ioctl_scrub_args *sa; 4107 int ret; 4108 4109 if (!capable(CAP_SYS_ADMIN)) 4110 return -EPERM; 4111 4112 sa = memdup_user(arg, sizeof(*sa)); 4113 if (IS_ERR(sa)) 4114 return PTR_ERR(sa); 4115 4116 if (!(sa->flags & BTRFS_SCRUB_READONLY)) { 4117 ret = mnt_want_write_file(file); 4118 if (ret) 4119 goto out; 4120 } 4121 4122 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end, 4123 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY, 4124 0); 4125 4126 if (copy_to_user(arg, sa, sizeof(*sa))) 4127 ret = -EFAULT; 4128 4129 if (!(sa->flags & BTRFS_SCRUB_READONLY)) 4130 mnt_drop_write_file(file); 4131 out: 4132 kfree(sa); 4133 return ret; 4134 } 4135 4136 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg) 4137 { 4138 if (!capable(CAP_SYS_ADMIN)) 4139 return -EPERM; 4140 4141 return btrfs_scrub_cancel(root->fs_info); 4142 } 4143 4144 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, 4145 void __user *arg) 4146 { 4147 struct btrfs_ioctl_scrub_args *sa; 4148 int ret; 4149 4150 if (!capable(CAP_SYS_ADMIN)) 4151 return -EPERM; 4152 4153 sa = memdup_user(arg, sizeof(*sa)); 4154 if (IS_ERR(sa)) 4155 return PTR_ERR(sa); 4156 4157 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress); 4158 4159 if (copy_to_user(arg, sa, sizeof(*sa))) 4160 ret = -EFAULT; 4161 4162 kfree(sa); 4163 return ret; 4164 } 4165 4166 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root, 4167 void __user *arg) 4168 { 4169 struct btrfs_ioctl_get_dev_stats *sa; 4170 int ret; 4171 4172 sa = memdup_user(arg, sizeof(*sa)); 4173 if (IS_ERR(sa)) 4174 return PTR_ERR(sa); 4175 4176 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) { 4177 kfree(sa); 4178 return -EPERM; 4179 } 4180 4181 ret = btrfs_get_dev_stats(root, sa); 4182 4183 if (copy_to_user(arg, sa, sizeof(*sa))) 4184 ret = -EFAULT; 4185 4186 kfree(sa); 4187 return ret; 4188 } 4189 4190 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg) 4191 { 4192 struct btrfs_ioctl_dev_replace_args *p; 4193 int ret; 4194 4195 if (!capable(CAP_SYS_ADMIN)) 4196 return -EPERM; 4197 4198 p = memdup_user(arg, sizeof(*p)); 4199 if (IS_ERR(p)) 4200 return PTR_ERR(p); 4201 4202 switch (p->cmd) { 4203 case BTRFS_IOCTL_DEV_REPLACE_CMD_START: 4204 if (root->fs_info->sb->s_flags & MS_RDONLY) { 4205 ret = -EROFS; 4206 goto out; 4207 } 4208 if (atomic_xchg( 4209 &root->fs_info->mutually_exclusive_operation_running, 4210 1)) { 4211 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 4212 } else { 4213 ret = btrfs_dev_replace_start(root, p); 4214 atomic_set( 4215 &root->fs_info->mutually_exclusive_operation_running, 4216 0); 4217 } 4218 break; 4219 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS: 4220 btrfs_dev_replace_status(root->fs_info, p); 4221 ret = 0; 4222 break; 4223 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL: 4224 ret = btrfs_dev_replace_cancel(root->fs_info, p); 4225 break; 4226 default: 4227 ret = -EINVAL; 4228 break; 4229 } 4230 4231 if (copy_to_user(arg, p, sizeof(*p))) 4232 ret = -EFAULT; 4233 out: 4234 kfree(p); 4235 return ret; 4236 } 4237 4238 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) 4239 { 4240 int ret = 0; 4241 int i; 4242 u64 rel_ptr; 4243 int size; 4244 struct btrfs_ioctl_ino_path_args *ipa = NULL; 4245 struct inode_fs_paths *ipath = NULL; 4246 struct btrfs_path *path; 4247 4248 if (!capable(CAP_DAC_READ_SEARCH)) 4249 return -EPERM; 4250 4251 path = btrfs_alloc_path(); 4252 if (!path) { 4253 ret = -ENOMEM; 4254 goto out; 4255 } 4256 4257 ipa = memdup_user(arg, sizeof(*ipa)); 4258 if (IS_ERR(ipa)) { 4259 ret = PTR_ERR(ipa); 4260 ipa = NULL; 4261 goto out; 4262 } 4263 4264 size = min_t(u32, ipa->size, 4096); 4265 ipath = init_ipath(size, root, path); 4266 if (IS_ERR(ipath)) { 4267 ret = PTR_ERR(ipath); 4268 ipath = NULL; 4269 goto out; 4270 } 4271 4272 ret = paths_from_inode(ipa->inum, ipath); 4273 if (ret < 0) 4274 goto out; 4275 4276 for (i = 0; i < ipath->fspath->elem_cnt; ++i) { 4277 rel_ptr = ipath->fspath->val[i] - 4278 (u64)(unsigned long)ipath->fspath->val; 4279 ipath->fspath->val[i] = rel_ptr; 4280 } 4281 4282 ret = copy_to_user((void *)(unsigned long)ipa->fspath, 4283 (void *)(unsigned long)ipath->fspath, size); 4284 if (ret) { 4285 ret = -EFAULT; 4286 goto out; 4287 } 4288 4289 out: 4290 btrfs_free_path(path); 4291 free_ipath(ipath); 4292 kfree(ipa); 4293 4294 return ret; 4295 } 4296 4297 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) 4298 { 4299 struct btrfs_data_container *inodes = ctx; 4300 const size_t c = 3 * sizeof(u64); 4301 4302 if (inodes->bytes_left >= c) { 4303 inodes->bytes_left -= c; 4304 inodes->val[inodes->elem_cnt] = inum; 4305 inodes->val[inodes->elem_cnt + 1] = offset; 4306 inodes->val[inodes->elem_cnt + 2] = root; 4307 inodes->elem_cnt += 3; 4308 } else { 4309 inodes->bytes_missing += c - inodes->bytes_left; 4310 inodes->bytes_left = 0; 4311 inodes->elem_missed += 3; 4312 } 4313 4314 return 0; 4315 } 4316 4317 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 4318 void __user *arg) 4319 { 4320 int ret = 0; 4321 int size; 4322 struct btrfs_ioctl_logical_ino_args *loi; 4323 struct btrfs_data_container *inodes = NULL; 4324 struct btrfs_path *path = NULL; 4325 4326 if (!capable(CAP_SYS_ADMIN)) 4327 return -EPERM; 4328 4329 loi = memdup_user(arg, sizeof(*loi)); 4330 if (IS_ERR(loi)) { 4331 ret = PTR_ERR(loi); 4332 loi = NULL; 4333 goto out; 4334 } 4335 4336 path = btrfs_alloc_path(); 4337 if (!path) { 4338 ret = -ENOMEM; 4339 goto out; 4340 } 4341 4342 size = min_t(u32, loi->size, 64 * 1024); 4343 inodes = init_data_container(size); 4344 if (IS_ERR(inodes)) { 4345 ret = PTR_ERR(inodes); 4346 inodes = NULL; 4347 goto out; 4348 } 4349 4350 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path, 4351 build_ino_list, inodes); 4352 if (ret == -EINVAL) 4353 ret = -ENOENT; 4354 if (ret < 0) 4355 goto out; 4356 4357 ret = copy_to_user((void *)(unsigned long)loi->inodes, 4358 (void *)(unsigned long)inodes, size); 4359 if (ret) 4360 ret = -EFAULT; 4361 4362 out: 4363 btrfs_free_path(path); 4364 vfree(inodes); 4365 kfree(loi); 4366 4367 return ret; 4368 } 4369 4370 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 4371 struct btrfs_ioctl_balance_args *bargs) 4372 { 4373 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 4374 4375 bargs->flags = bctl->flags; 4376 4377 if (atomic_read(&fs_info->balance_running)) 4378 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 4379 if (atomic_read(&fs_info->balance_pause_req)) 4380 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 4381 if (atomic_read(&fs_info->balance_cancel_req)) 4382 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 4383 4384 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 4385 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 4386 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 4387 4388 if (lock) { 4389 spin_lock(&fs_info->balance_lock); 4390 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 4391 spin_unlock(&fs_info->balance_lock); 4392 } else { 4393 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 4394 } 4395 } 4396 4397 static long btrfs_ioctl_balance(struct file *file, void __user *arg) 4398 { 4399 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4400 struct btrfs_fs_info *fs_info = root->fs_info; 4401 struct btrfs_ioctl_balance_args *bargs; 4402 struct btrfs_balance_control *bctl; 4403 bool need_unlock; /* for mut. excl. ops lock */ 4404 int ret; 4405 4406 if (!capable(CAP_SYS_ADMIN)) 4407 return -EPERM; 4408 4409 ret = mnt_want_write_file(file); 4410 if (ret) 4411 return ret; 4412 4413 again: 4414 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) { 4415 mutex_lock(&fs_info->volume_mutex); 4416 mutex_lock(&fs_info->balance_mutex); 4417 need_unlock = true; 4418 goto locked; 4419 } 4420 4421 /* 4422 * mut. excl. ops lock is locked. Three possibilites: 4423 * (1) some other op is running 4424 * (2) balance is running 4425 * (3) balance is paused -- special case (think resume) 4426 */ 4427 mutex_lock(&fs_info->balance_mutex); 4428 if (fs_info->balance_ctl) { 4429 /* this is either (2) or (3) */ 4430 if (!atomic_read(&fs_info->balance_running)) { 4431 mutex_unlock(&fs_info->balance_mutex); 4432 if (!mutex_trylock(&fs_info->volume_mutex)) 4433 goto again; 4434 mutex_lock(&fs_info->balance_mutex); 4435 4436 if (fs_info->balance_ctl && 4437 !atomic_read(&fs_info->balance_running)) { 4438 /* this is (3) */ 4439 need_unlock = false; 4440 goto locked; 4441 } 4442 4443 mutex_unlock(&fs_info->balance_mutex); 4444 mutex_unlock(&fs_info->volume_mutex); 4445 goto again; 4446 } else { 4447 /* this is (2) */ 4448 mutex_unlock(&fs_info->balance_mutex); 4449 ret = -EINPROGRESS; 4450 goto out; 4451 } 4452 } else { 4453 /* this is (1) */ 4454 mutex_unlock(&fs_info->balance_mutex); 4455 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 4456 goto out; 4457 } 4458 4459 locked: 4460 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running)); 4461 4462 if (arg) { 4463 bargs = memdup_user(arg, sizeof(*bargs)); 4464 if (IS_ERR(bargs)) { 4465 ret = PTR_ERR(bargs); 4466 goto out_unlock; 4467 } 4468 4469 if (bargs->flags & BTRFS_BALANCE_RESUME) { 4470 if (!fs_info->balance_ctl) { 4471 ret = -ENOTCONN; 4472 goto out_bargs; 4473 } 4474 4475 bctl = fs_info->balance_ctl; 4476 spin_lock(&fs_info->balance_lock); 4477 bctl->flags |= BTRFS_BALANCE_RESUME; 4478 spin_unlock(&fs_info->balance_lock); 4479 4480 goto do_balance; 4481 } 4482 } else { 4483 bargs = NULL; 4484 } 4485 4486 if (fs_info->balance_ctl) { 4487 ret = -EINPROGRESS; 4488 goto out_bargs; 4489 } 4490 4491 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 4492 if (!bctl) { 4493 ret = -ENOMEM; 4494 goto out_bargs; 4495 } 4496 4497 bctl->fs_info = fs_info; 4498 if (arg) { 4499 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 4500 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 4501 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 4502 4503 bctl->flags = bargs->flags; 4504 } else { 4505 /* balance everything - no filters */ 4506 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 4507 } 4508 4509 do_balance: 4510 /* 4511 * Ownership of bctl and mutually_exclusive_operation_running 4512 * goes to to btrfs_balance. bctl is freed in __cancel_balance, 4513 * or, if restriper was paused all the way until unmount, in 4514 * free_fs_info. mutually_exclusive_operation_running is 4515 * cleared in __cancel_balance. 4516 */ 4517 need_unlock = false; 4518 4519 ret = btrfs_balance(bctl, bargs); 4520 4521 if (arg) { 4522 if (copy_to_user(arg, bargs, sizeof(*bargs))) 4523 ret = -EFAULT; 4524 } 4525 4526 out_bargs: 4527 kfree(bargs); 4528 out_unlock: 4529 mutex_unlock(&fs_info->balance_mutex); 4530 mutex_unlock(&fs_info->volume_mutex); 4531 if (need_unlock) 4532 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 4533 out: 4534 mnt_drop_write_file(file); 4535 return ret; 4536 } 4537 4538 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) 4539 { 4540 if (!capable(CAP_SYS_ADMIN)) 4541 return -EPERM; 4542 4543 switch (cmd) { 4544 case BTRFS_BALANCE_CTL_PAUSE: 4545 return btrfs_pause_balance(root->fs_info); 4546 case BTRFS_BALANCE_CTL_CANCEL: 4547 return btrfs_cancel_balance(root->fs_info); 4548 } 4549 4550 return -EINVAL; 4551 } 4552 4553 static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 4554 void __user *arg) 4555 { 4556 struct btrfs_fs_info *fs_info = root->fs_info; 4557 struct btrfs_ioctl_balance_args *bargs; 4558 int ret = 0; 4559 4560 if (!capable(CAP_SYS_ADMIN)) 4561 return -EPERM; 4562 4563 mutex_lock(&fs_info->balance_mutex); 4564 if (!fs_info->balance_ctl) { 4565 ret = -ENOTCONN; 4566 goto out; 4567 } 4568 4569 bargs = kzalloc(sizeof(*bargs), GFP_NOFS); 4570 if (!bargs) { 4571 ret = -ENOMEM; 4572 goto out; 4573 } 4574 4575 update_ioctl_balance_args(fs_info, 1, bargs); 4576 4577 if (copy_to_user(arg, bargs, sizeof(*bargs))) 4578 ret = -EFAULT; 4579 4580 kfree(bargs); 4581 out: 4582 mutex_unlock(&fs_info->balance_mutex); 4583 return ret; 4584 } 4585 4586 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg) 4587 { 4588 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4589 struct btrfs_ioctl_quota_ctl_args *sa; 4590 struct btrfs_trans_handle *trans = NULL; 4591 int ret; 4592 int err; 4593 4594 if (!capable(CAP_SYS_ADMIN)) 4595 return -EPERM; 4596 4597 ret = mnt_want_write_file(file); 4598 if (ret) 4599 return ret; 4600 4601 sa = memdup_user(arg, sizeof(*sa)); 4602 if (IS_ERR(sa)) { 4603 ret = PTR_ERR(sa); 4604 goto drop_write; 4605 } 4606 4607 down_write(&root->fs_info->subvol_sem); 4608 trans = btrfs_start_transaction(root->fs_info->tree_root, 2); 4609 if (IS_ERR(trans)) { 4610 ret = PTR_ERR(trans); 4611 goto out; 4612 } 4613 4614 switch (sa->cmd) { 4615 case BTRFS_QUOTA_CTL_ENABLE: 4616 ret = btrfs_quota_enable(trans, root->fs_info); 4617 break; 4618 case BTRFS_QUOTA_CTL_DISABLE: 4619 ret = btrfs_quota_disable(trans, root->fs_info); 4620 break; 4621 default: 4622 ret = -EINVAL; 4623 break; 4624 } 4625 4626 err = btrfs_commit_transaction(trans, root->fs_info->tree_root); 4627 if (err && !ret) 4628 ret = err; 4629 out: 4630 kfree(sa); 4631 up_write(&root->fs_info->subvol_sem); 4632 drop_write: 4633 mnt_drop_write_file(file); 4634 return ret; 4635 } 4636 4637 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg) 4638 { 4639 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4640 struct btrfs_ioctl_qgroup_assign_args *sa; 4641 struct btrfs_trans_handle *trans; 4642 int ret; 4643 int err; 4644 4645 if (!capable(CAP_SYS_ADMIN)) 4646 return -EPERM; 4647 4648 ret = mnt_want_write_file(file); 4649 if (ret) 4650 return ret; 4651 4652 sa = memdup_user(arg, sizeof(*sa)); 4653 if (IS_ERR(sa)) { 4654 ret = PTR_ERR(sa); 4655 goto drop_write; 4656 } 4657 4658 trans = btrfs_join_transaction(root); 4659 if (IS_ERR(trans)) { 4660 ret = PTR_ERR(trans); 4661 goto out; 4662 } 4663 4664 /* FIXME: check if the IDs really exist */ 4665 if (sa->assign) { 4666 ret = btrfs_add_qgroup_relation(trans, root->fs_info, 4667 sa->src, sa->dst); 4668 } else { 4669 ret = btrfs_del_qgroup_relation(trans, root->fs_info, 4670 sa->src, sa->dst); 4671 } 4672 4673 err = btrfs_end_transaction(trans, root); 4674 if (err && !ret) 4675 ret = err; 4676 4677 out: 4678 kfree(sa); 4679 drop_write: 4680 mnt_drop_write_file(file); 4681 return ret; 4682 } 4683 4684 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg) 4685 { 4686 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4687 struct btrfs_ioctl_qgroup_create_args *sa; 4688 struct btrfs_trans_handle *trans; 4689 int ret; 4690 int err; 4691 4692 if (!capable(CAP_SYS_ADMIN)) 4693 return -EPERM; 4694 4695 ret = mnt_want_write_file(file); 4696 if (ret) 4697 return ret; 4698 4699 sa = memdup_user(arg, sizeof(*sa)); 4700 if (IS_ERR(sa)) { 4701 ret = PTR_ERR(sa); 4702 goto drop_write; 4703 } 4704 4705 if (!sa->qgroupid) { 4706 ret = -EINVAL; 4707 goto out; 4708 } 4709 4710 trans = btrfs_join_transaction(root); 4711 if (IS_ERR(trans)) { 4712 ret = PTR_ERR(trans); 4713 goto out; 4714 } 4715 4716 /* FIXME: check if the IDs really exist */ 4717 if (sa->create) { 4718 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid, 4719 NULL); 4720 } else { 4721 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid); 4722 } 4723 4724 err = btrfs_end_transaction(trans, root); 4725 if (err && !ret) 4726 ret = err; 4727 4728 out: 4729 kfree(sa); 4730 drop_write: 4731 mnt_drop_write_file(file); 4732 return ret; 4733 } 4734 4735 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg) 4736 { 4737 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4738 struct btrfs_ioctl_qgroup_limit_args *sa; 4739 struct btrfs_trans_handle *trans; 4740 int ret; 4741 int err; 4742 u64 qgroupid; 4743 4744 if (!capable(CAP_SYS_ADMIN)) 4745 return -EPERM; 4746 4747 ret = mnt_want_write_file(file); 4748 if (ret) 4749 return ret; 4750 4751 sa = memdup_user(arg, sizeof(*sa)); 4752 if (IS_ERR(sa)) { 4753 ret = PTR_ERR(sa); 4754 goto drop_write; 4755 } 4756 4757 trans = btrfs_join_transaction(root); 4758 if (IS_ERR(trans)) { 4759 ret = PTR_ERR(trans); 4760 goto out; 4761 } 4762 4763 qgroupid = sa->qgroupid; 4764 if (!qgroupid) { 4765 /* take the current subvol as qgroup */ 4766 qgroupid = root->root_key.objectid; 4767 } 4768 4769 /* FIXME: check if the IDs really exist */ 4770 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim); 4771 4772 err = btrfs_end_transaction(trans, root); 4773 if (err && !ret) 4774 ret = err; 4775 4776 out: 4777 kfree(sa); 4778 drop_write: 4779 mnt_drop_write_file(file); 4780 return ret; 4781 } 4782 4783 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg) 4784 { 4785 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4786 struct btrfs_ioctl_quota_rescan_args *qsa; 4787 int ret; 4788 4789 if (!capable(CAP_SYS_ADMIN)) 4790 return -EPERM; 4791 4792 ret = mnt_want_write_file(file); 4793 if (ret) 4794 return ret; 4795 4796 qsa = memdup_user(arg, sizeof(*qsa)); 4797 if (IS_ERR(qsa)) { 4798 ret = PTR_ERR(qsa); 4799 goto drop_write; 4800 } 4801 4802 if (qsa->flags) { 4803 ret = -EINVAL; 4804 goto out; 4805 } 4806 4807 ret = btrfs_qgroup_rescan(root->fs_info); 4808 4809 out: 4810 kfree(qsa); 4811 drop_write: 4812 mnt_drop_write_file(file); 4813 return ret; 4814 } 4815 4816 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg) 4817 { 4818 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4819 struct btrfs_ioctl_quota_rescan_args *qsa; 4820 int ret = 0; 4821 4822 if (!capable(CAP_SYS_ADMIN)) 4823 return -EPERM; 4824 4825 qsa = kzalloc(sizeof(*qsa), GFP_NOFS); 4826 if (!qsa) 4827 return -ENOMEM; 4828 4829 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { 4830 qsa->flags = 1; 4831 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid; 4832 } 4833 4834 if (copy_to_user(arg, qsa, sizeof(*qsa))) 4835 ret = -EFAULT; 4836 4837 kfree(qsa); 4838 return ret; 4839 } 4840 4841 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg) 4842 { 4843 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4844 4845 if (!capable(CAP_SYS_ADMIN)) 4846 return -EPERM; 4847 4848 return btrfs_qgroup_wait_for_completion(root->fs_info); 4849 } 4850 4851 static long _btrfs_ioctl_set_received_subvol(struct file *file, 4852 struct btrfs_ioctl_received_subvol_args *sa) 4853 { 4854 struct inode *inode = file_inode(file); 4855 struct btrfs_root *root = BTRFS_I(inode)->root; 4856 struct btrfs_root_item *root_item = &root->root_item; 4857 struct btrfs_trans_handle *trans; 4858 struct timespec ct = CURRENT_TIME; 4859 int ret = 0; 4860 int received_uuid_changed; 4861 4862 if (!inode_owner_or_capable(inode)) 4863 return -EPERM; 4864 4865 ret = mnt_want_write_file(file); 4866 if (ret < 0) 4867 return ret; 4868 4869 down_write(&root->fs_info->subvol_sem); 4870 4871 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { 4872 ret = -EINVAL; 4873 goto out; 4874 } 4875 4876 if (btrfs_root_readonly(root)) { 4877 ret = -EROFS; 4878 goto out; 4879 } 4880 4881 /* 4882 * 1 - root item 4883 * 2 - uuid items (received uuid + subvol uuid) 4884 */ 4885 trans = btrfs_start_transaction(root, 3); 4886 if (IS_ERR(trans)) { 4887 ret = PTR_ERR(trans); 4888 trans = NULL; 4889 goto out; 4890 } 4891 4892 sa->rtransid = trans->transid; 4893 sa->rtime.sec = ct.tv_sec; 4894 sa->rtime.nsec = ct.tv_nsec; 4895 4896 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid, 4897 BTRFS_UUID_SIZE); 4898 if (received_uuid_changed && 4899 !btrfs_is_empty_uuid(root_item->received_uuid)) 4900 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, 4901 root_item->received_uuid, 4902 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 4903 root->root_key.objectid); 4904 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); 4905 btrfs_set_root_stransid(root_item, sa->stransid); 4906 btrfs_set_root_rtransid(root_item, sa->rtransid); 4907 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec); 4908 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec); 4909 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec); 4910 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec); 4911 4912 ret = btrfs_update_root(trans, root->fs_info->tree_root, 4913 &root->root_key, &root->root_item); 4914 if (ret < 0) { 4915 btrfs_end_transaction(trans, root); 4916 goto out; 4917 } 4918 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) { 4919 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root, 4920 sa->uuid, 4921 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 4922 root->root_key.objectid); 4923 if (ret < 0 && ret != -EEXIST) { 4924 btrfs_abort_transaction(trans, root, ret); 4925 goto out; 4926 } 4927 } 4928 ret = btrfs_commit_transaction(trans, root); 4929 if (ret < 0) { 4930 btrfs_abort_transaction(trans, root, ret); 4931 goto out; 4932 } 4933 4934 out: 4935 up_write(&root->fs_info->subvol_sem); 4936 mnt_drop_write_file(file); 4937 return ret; 4938 } 4939 4940 #ifdef CONFIG_64BIT 4941 static long btrfs_ioctl_set_received_subvol_32(struct file *file, 4942 void __user *arg) 4943 { 4944 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL; 4945 struct btrfs_ioctl_received_subvol_args *args64 = NULL; 4946 int ret = 0; 4947 4948 args32 = memdup_user(arg, sizeof(*args32)); 4949 if (IS_ERR(args32)) { 4950 ret = PTR_ERR(args32); 4951 args32 = NULL; 4952 goto out; 4953 } 4954 4955 args64 = kmalloc(sizeof(*args64), GFP_NOFS); 4956 if (!args64) { 4957 ret = -ENOMEM; 4958 goto out; 4959 } 4960 4961 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE); 4962 args64->stransid = args32->stransid; 4963 args64->rtransid = args32->rtransid; 4964 args64->stime.sec = args32->stime.sec; 4965 args64->stime.nsec = args32->stime.nsec; 4966 args64->rtime.sec = args32->rtime.sec; 4967 args64->rtime.nsec = args32->rtime.nsec; 4968 args64->flags = args32->flags; 4969 4970 ret = _btrfs_ioctl_set_received_subvol(file, args64); 4971 if (ret) 4972 goto out; 4973 4974 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE); 4975 args32->stransid = args64->stransid; 4976 args32->rtransid = args64->rtransid; 4977 args32->stime.sec = args64->stime.sec; 4978 args32->stime.nsec = args64->stime.nsec; 4979 args32->rtime.sec = args64->rtime.sec; 4980 args32->rtime.nsec = args64->rtime.nsec; 4981 args32->flags = args64->flags; 4982 4983 ret = copy_to_user(arg, args32, sizeof(*args32)); 4984 if (ret) 4985 ret = -EFAULT; 4986 4987 out: 4988 kfree(args32); 4989 kfree(args64); 4990 return ret; 4991 } 4992 #endif 4993 4994 static long btrfs_ioctl_set_received_subvol(struct file *file, 4995 void __user *arg) 4996 { 4997 struct btrfs_ioctl_received_subvol_args *sa = NULL; 4998 int ret = 0; 4999 5000 sa = memdup_user(arg, sizeof(*sa)); 5001 if (IS_ERR(sa)) { 5002 ret = PTR_ERR(sa); 5003 sa = NULL; 5004 goto out; 5005 } 5006 5007 ret = _btrfs_ioctl_set_received_subvol(file, sa); 5008 5009 if (ret) 5010 goto out; 5011 5012 ret = copy_to_user(arg, sa, sizeof(*sa)); 5013 if (ret) 5014 ret = -EFAULT; 5015 5016 out: 5017 kfree(sa); 5018 return ret; 5019 } 5020 5021 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) 5022 { 5023 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5024 size_t len; 5025 int ret; 5026 char label[BTRFS_LABEL_SIZE]; 5027 5028 spin_lock(&root->fs_info->super_lock); 5029 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE); 5030 spin_unlock(&root->fs_info->super_lock); 5031 5032 len = strnlen(label, BTRFS_LABEL_SIZE); 5033 5034 if (len == BTRFS_LABEL_SIZE) { 5035 btrfs_warn(root->fs_info, 5036 "label is too long, return the first %zu bytes", --len); 5037 } 5038 5039 ret = copy_to_user(arg, label, len); 5040 5041 return ret ? -EFAULT : 0; 5042 } 5043 5044 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) 5045 { 5046 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5047 struct btrfs_super_block *super_block = root->fs_info->super_copy; 5048 struct btrfs_trans_handle *trans; 5049 char label[BTRFS_LABEL_SIZE]; 5050 int ret; 5051 5052 if (!capable(CAP_SYS_ADMIN)) 5053 return -EPERM; 5054 5055 if (copy_from_user(label, arg, sizeof(label))) 5056 return -EFAULT; 5057 5058 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) { 5059 btrfs_err(root->fs_info, "unable to set label with more than %d bytes", 5060 BTRFS_LABEL_SIZE - 1); 5061 return -EINVAL; 5062 } 5063 5064 ret = mnt_want_write_file(file); 5065 if (ret) 5066 return ret; 5067 5068 trans = btrfs_start_transaction(root, 0); 5069 if (IS_ERR(trans)) { 5070 ret = PTR_ERR(trans); 5071 goto out_unlock; 5072 } 5073 5074 spin_lock(&root->fs_info->super_lock); 5075 strcpy(super_block->label, label); 5076 spin_unlock(&root->fs_info->super_lock); 5077 ret = btrfs_commit_transaction(trans, root); 5078 5079 out_unlock: 5080 mnt_drop_write_file(file); 5081 return ret; 5082 } 5083 5084 #define INIT_FEATURE_FLAGS(suffix) \ 5085 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \ 5086 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \ 5087 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix } 5088 5089 static int btrfs_ioctl_get_supported_features(struct file *file, 5090 void __user *arg) 5091 { 5092 static struct btrfs_ioctl_feature_flags features[3] = { 5093 INIT_FEATURE_FLAGS(SUPP), 5094 INIT_FEATURE_FLAGS(SAFE_SET), 5095 INIT_FEATURE_FLAGS(SAFE_CLEAR) 5096 }; 5097 5098 if (copy_to_user(arg, &features, sizeof(features))) 5099 return -EFAULT; 5100 5101 return 0; 5102 } 5103 5104 static int btrfs_ioctl_get_features(struct file *file, void __user *arg) 5105 { 5106 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5107 struct btrfs_super_block *super_block = root->fs_info->super_copy; 5108 struct btrfs_ioctl_feature_flags features; 5109 5110 features.compat_flags = btrfs_super_compat_flags(super_block); 5111 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block); 5112 features.incompat_flags = btrfs_super_incompat_flags(super_block); 5113 5114 if (copy_to_user(arg, &features, sizeof(features))) 5115 return -EFAULT; 5116 5117 return 0; 5118 } 5119 5120 static int check_feature_bits(struct btrfs_root *root, 5121 enum btrfs_feature_set set, 5122 u64 change_mask, u64 flags, u64 supported_flags, 5123 u64 safe_set, u64 safe_clear) 5124 { 5125 const char *type = btrfs_feature_set_names[set]; 5126 char *names; 5127 u64 disallowed, unsupported; 5128 u64 set_mask = flags & change_mask; 5129 u64 clear_mask = ~flags & change_mask; 5130 5131 unsupported = set_mask & ~supported_flags; 5132 if (unsupported) { 5133 names = btrfs_printable_features(set, unsupported); 5134 if (names) { 5135 btrfs_warn(root->fs_info, 5136 "this kernel does not support the %s feature bit%s", 5137 names, strchr(names, ',') ? "s" : ""); 5138 kfree(names); 5139 } else 5140 btrfs_warn(root->fs_info, 5141 "this kernel does not support %s bits 0x%llx", 5142 type, unsupported); 5143 return -EOPNOTSUPP; 5144 } 5145 5146 disallowed = set_mask & ~safe_set; 5147 if (disallowed) { 5148 names = btrfs_printable_features(set, disallowed); 5149 if (names) { 5150 btrfs_warn(root->fs_info, 5151 "can't set the %s feature bit%s while mounted", 5152 names, strchr(names, ',') ? "s" : ""); 5153 kfree(names); 5154 } else 5155 btrfs_warn(root->fs_info, 5156 "can't set %s bits 0x%llx while mounted", 5157 type, disallowed); 5158 return -EPERM; 5159 } 5160 5161 disallowed = clear_mask & ~safe_clear; 5162 if (disallowed) { 5163 names = btrfs_printable_features(set, disallowed); 5164 if (names) { 5165 btrfs_warn(root->fs_info, 5166 "can't clear the %s feature bit%s while mounted", 5167 names, strchr(names, ',') ? "s" : ""); 5168 kfree(names); 5169 } else 5170 btrfs_warn(root->fs_info, 5171 "can't clear %s bits 0x%llx while mounted", 5172 type, disallowed); 5173 return -EPERM; 5174 } 5175 5176 return 0; 5177 } 5178 5179 #define check_feature(root, change_mask, flags, mask_base) \ 5180 check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \ 5181 BTRFS_FEATURE_ ## mask_base ## _SUPP, \ 5182 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \ 5183 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR) 5184 5185 static int btrfs_ioctl_set_features(struct file *file, void __user *arg) 5186 { 5187 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5188 struct btrfs_super_block *super_block = root->fs_info->super_copy; 5189 struct btrfs_ioctl_feature_flags flags[2]; 5190 struct btrfs_trans_handle *trans; 5191 u64 newflags; 5192 int ret; 5193 5194 if (!capable(CAP_SYS_ADMIN)) 5195 return -EPERM; 5196 5197 if (copy_from_user(flags, arg, sizeof(flags))) 5198 return -EFAULT; 5199 5200 /* Nothing to do */ 5201 if (!flags[0].compat_flags && !flags[0].compat_ro_flags && 5202 !flags[0].incompat_flags) 5203 return 0; 5204 5205 ret = check_feature(root, flags[0].compat_flags, 5206 flags[1].compat_flags, COMPAT); 5207 if (ret) 5208 return ret; 5209 5210 ret = check_feature(root, flags[0].compat_ro_flags, 5211 flags[1].compat_ro_flags, COMPAT_RO); 5212 if (ret) 5213 return ret; 5214 5215 ret = check_feature(root, flags[0].incompat_flags, 5216 flags[1].incompat_flags, INCOMPAT); 5217 if (ret) 5218 return ret; 5219 5220 trans = btrfs_start_transaction(root, 0); 5221 if (IS_ERR(trans)) 5222 return PTR_ERR(trans); 5223 5224 spin_lock(&root->fs_info->super_lock); 5225 newflags = btrfs_super_compat_flags(super_block); 5226 newflags |= flags[0].compat_flags & flags[1].compat_flags; 5227 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags); 5228 btrfs_set_super_compat_flags(super_block, newflags); 5229 5230 newflags = btrfs_super_compat_ro_flags(super_block); 5231 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags; 5232 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags); 5233 btrfs_set_super_compat_ro_flags(super_block, newflags); 5234 5235 newflags = btrfs_super_incompat_flags(super_block); 5236 newflags |= flags[0].incompat_flags & flags[1].incompat_flags; 5237 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags); 5238 btrfs_set_super_incompat_flags(super_block, newflags); 5239 spin_unlock(&root->fs_info->super_lock); 5240 5241 return btrfs_commit_transaction(trans, root); 5242 } 5243 5244 long btrfs_ioctl(struct file *file, unsigned int 5245 cmd, unsigned long arg) 5246 { 5247 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 5248 void __user *argp = (void __user *)arg; 5249 5250 switch (cmd) { 5251 case FS_IOC_GETFLAGS: 5252 return btrfs_ioctl_getflags(file, argp); 5253 case FS_IOC_SETFLAGS: 5254 return btrfs_ioctl_setflags(file, argp); 5255 case FS_IOC_GETVERSION: 5256 return btrfs_ioctl_getversion(file, argp); 5257 case FITRIM: 5258 return btrfs_ioctl_fitrim(file, argp); 5259 case BTRFS_IOC_SNAP_CREATE: 5260 return btrfs_ioctl_snap_create(file, argp, 0); 5261 case BTRFS_IOC_SNAP_CREATE_V2: 5262 return btrfs_ioctl_snap_create_v2(file, argp, 0); 5263 case BTRFS_IOC_SUBVOL_CREATE: 5264 return btrfs_ioctl_snap_create(file, argp, 1); 5265 case BTRFS_IOC_SUBVOL_CREATE_V2: 5266 return btrfs_ioctl_snap_create_v2(file, argp, 1); 5267 case BTRFS_IOC_SNAP_DESTROY: 5268 return btrfs_ioctl_snap_destroy(file, argp); 5269 case BTRFS_IOC_SUBVOL_GETFLAGS: 5270 return btrfs_ioctl_subvol_getflags(file, argp); 5271 case BTRFS_IOC_SUBVOL_SETFLAGS: 5272 return btrfs_ioctl_subvol_setflags(file, argp); 5273 case BTRFS_IOC_DEFAULT_SUBVOL: 5274 return btrfs_ioctl_default_subvol(file, argp); 5275 case BTRFS_IOC_DEFRAG: 5276 return btrfs_ioctl_defrag(file, NULL); 5277 case BTRFS_IOC_DEFRAG_RANGE: 5278 return btrfs_ioctl_defrag(file, argp); 5279 case BTRFS_IOC_RESIZE: 5280 return btrfs_ioctl_resize(file, argp); 5281 case BTRFS_IOC_ADD_DEV: 5282 return btrfs_ioctl_add_dev(root, argp); 5283 case BTRFS_IOC_RM_DEV: 5284 return btrfs_ioctl_rm_dev(file, argp); 5285 case BTRFS_IOC_FS_INFO: 5286 return btrfs_ioctl_fs_info(root, argp); 5287 case BTRFS_IOC_DEV_INFO: 5288 return btrfs_ioctl_dev_info(root, argp); 5289 case BTRFS_IOC_BALANCE: 5290 return btrfs_ioctl_balance(file, NULL); 5291 case BTRFS_IOC_CLONE: 5292 return btrfs_ioctl_clone(file, arg, 0, 0, 0); 5293 case BTRFS_IOC_CLONE_RANGE: 5294 return btrfs_ioctl_clone_range(file, argp); 5295 case BTRFS_IOC_TRANS_START: 5296 return btrfs_ioctl_trans_start(file); 5297 case BTRFS_IOC_TRANS_END: 5298 return btrfs_ioctl_trans_end(file); 5299 case BTRFS_IOC_TREE_SEARCH: 5300 return btrfs_ioctl_tree_search(file, argp); 5301 case BTRFS_IOC_TREE_SEARCH_V2: 5302 return btrfs_ioctl_tree_search_v2(file, argp); 5303 case BTRFS_IOC_INO_LOOKUP: 5304 return btrfs_ioctl_ino_lookup(file, argp); 5305 case BTRFS_IOC_INO_PATHS: 5306 return btrfs_ioctl_ino_to_path(root, argp); 5307 case BTRFS_IOC_LOGICAL_INO: 5308 return btrfs_ioctl_logical_to_ino(root, argp); 5309 case BTRFS_IOC_SPACE_INFO: 5310 return btrfs_ioctl_space_info(root, argp); 5311 case BTRFS_IOC_SYNC: { 5312 int ret; 5313 5314 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1); 5315 if (ret) 5316 return ret; 5317 ret = btrfs_sync_fs(file->f_dentry->d_sb, 1); 5318 /* 5319 * The transaction thread may want to do more work, 5320 * namely it pokes the cleaner ktread that will start 5321 * processing uncleaned subvols. 5322 */ 5323 wake_up_process(root->fs_info->transaction_kthread); 5324 return ret; 5325 } 5326 case BTRFS_IOC_START_SYNC: 5327 return btrfs_ioctl_start_sync(root, argp); 5328 case BTRFS_IOC_WAIT_SYNC: 5329 return btrfs_ioctl_wait_sync(root, argp); 5330 case BTRFS_IOC_SCRUB: 5331 return btrfs_ioctl_scrub(file, argp); 5332 case BTRFS_IOC_SCRUB_CANCEL: 5333 return btrfs_ioctl_scrub_cancel(root, argp); 5334 case BTRFS_IOC_SCRUB_PROGRESS: 5335 return btrfs_ioctl_scrub_progress(root, argp); 5336 case BTRFS_IOC_BALANCE_V2: 5337 return btrfs_ioctl_balance(file, argp); 5338 case BTRFS_IOC_BALANCE_CTL: 5339 return btrfs_ioctl_balance_ctl(root, arg); 5340 case BTRFS_IOC_BALANCE_PROGRESS: 5341 return btrfs_ioctl_balance_progress(root, argp); 5342 case BTRFS_IOC_SET_RECEIVED_SUBVOL: 5343 return btrfs_ioctl_set_received_subvol(file, argp); 5344 #ifdef CONFIG_64BIT 5345 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32: 5346 return btrfs_ioctl_set_received_subvol_32(file, argp); 5347 #endif 5348 case BTRFS_IOC_SEND: 5349 return btrfs_ioctl_send(file, argp); 5350 case BTRFS_IOC_GET_DEV_STATS: 5351 return btrfs_ioctl_get_dev_stats(root, argp); 5352 case BTRFS_IOC_QUOTA_CTL: 5353 return btrfs_ioctl_quota_ctl(file, argp); 5354 case BTRFS_IOC_QGROUP_ASSIGN: 5355 return btrfs_ioctl_qgroup_assign(file, argp); 5356 case BTRFS_IOC_QGROUP_CREATE: 5357 return btrfs_ioctl_qgroup_create(file, argp); 5358 case BTRFS_IOC_QGROUP_LIMIT: 5359 return btrfs_ioctl_qgroup_limit(file, argp); 5360 case BTRFS_IOC_QUOTA_RESCAN: 5361 return btrfs_ioctl_quota_rescan(file, argp); 5362 case BTRFS_IOC_QUOTA_RESCAN_STATUS: 5363 return btrfs_ioctl_quota_rescan_status(file, argp); 5364 case BTRFS_IOC_QUOTA_RESCAN_WAIT: 5365 return btrfs_ioctl_quota_rescan_wait(file, argp); 5366 case BTRFS_IOC_DEV_REPLACE: 5367 return btrfs_ioctl_dev_replace(root, argp); 5368 case BTRFS_IOC_GET_FSLABEL: 5369 return btrfs_ioctl_get_fslabel(file, argp); 5370 case BTRFS_IOC_SET_FSLABEL: 5371 return btrfs_ioctl_set_fslabel(file, argp); 5372 case BTRFS_IOC_FILE_EXTENT_SAME: 5373 return btrfs_ioctl_file_extent_same(file, argp); 5374 case BTRFS_IOC_GET_SUPPORTED_FEATURES: 5375 return btrfs_ioctl_get_supported_features(file, argp); 5376 case BTRFS_IOC_GET_FEATURES: 5377 return btrfs_ioctl_get_features(file, argp); 5378 case BTRFS_IOC_SET_FEATURES: 5379 return btrfs_ioctl_set_features(file, argp); 5380 } 5381 5382 return -ENOTTY; 5383 } 5384