1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2007 Oracle. All rights reserved. 4 */ 5 6 #include <linux/kernel.h> 7 #include <linux/bio.h> 8 #include <linux/file.h> 9 #include <linux/fs.h> 10 #include <linux/fsnotify.h> 11 #include <linux/pagemap.h> 12 #include <linux/highmem.h> 13 #include <linux/time.h> 14 #include <linux/string.h> 15 #include <linux/backing-dev.h> 16 #include <linux/mount.h> 17 #include <linux/namei.h> 18 #include <linux/writeback.h> 19 #include <linux/compat.h> 20 #include <linux/security.h> 21 #include <linux/xattr.h> 22 #include <linux/mm.h> 23 #include <linux/slab.h> 24 #include <linux/blkdev.h> 25 #include <linux/uuid.h> 26 #include <linux/btrfs.h> 27 #include <linux/uaccess.h> 28 #include <linux/iversion.h> 29 #include "ctree.h" 30 #include "disk-io.h" 31 #include "transaction.h" 32 #include "btrfs_inode.h" 33 #include "print-tree.h" 34 #include "volumes.h" 35 #include "locking.h" 36 #include "inode-map.h" 37 #include "backref.h" 38 #include "rcu-string.h" 39 #include "send.h" 40 #include "dev-replace.h" 41 #include "props.h" 42 #include "sysfs.h" 43 #include "qgroup.h" 44 #include "tree-log.h" 45 #include "compression.h" 46 47 #ifdef CONFIG_64BIT 48 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI 49 * structures are incorrect, as the timespec structure from userspace 50 * is 4 bytes too small. We define these alternatives here to teach 51 * the kernel about the 32-bit struct packing. 52 */ 53 struct btrfs_ioctl_timespec_32 { 54 __u64 sec; 55 __u32 nsec; 56 } __attribute__ ((__packed__)); 57 58 struct btrfs_ioctl_received_subvol_args_32 { 59 char uuid[BTRFS_UUID_SIZE]; /* in */ 60 __u64 stransid; /* in */ 61 __u64 rtransid; /* out */ 62 struct btrfs_ioctl_timespec_32 stime; /* in */ 63 struct btrfs_ioctl_timespec_32 rtime; /* out */ 64 __u64 flags; /* in */ 65 __u64 reserved[16]; /* in */ 66 } __attribute__ ((__packed__)); 67 68 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \ 69 struct btrfs_ioctl_received_subvol_args_32) 70 #endif 71 72 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) 73 struct btrfs_ioctl_send_args_32 { 74 __s64 send_fd; /* in */ 75 __u64 clone_sources_count; /* in */ 76 compat_uptr_t clone_sources; /* in */ 77 __u64 parent_root; /* in */ 78 __u64 flags; /* in */ 79 __u64 reserved[4]; /* in */ 80 } __attribute__ ((__packed__)); 81 82 #define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \ 83 struct btrfs_ioctl_send_args_32) 84 #endif 85 86 static int btrfs_clone(struct inode *src, struct inode *inode, 87 u64 off, u64 olen, u64 olen_aligned, u64 destoff, 88 int no_time_update); 89 90 /* Mask out flags that are inappropriate for the given type of inode. */ 91 static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode, 92 unsigned int flags) 93 { 94 if (S_ISDIR(inode->i_mode)) 95 return flags; 96 else if (S_ISREG(inode->i_mode)) 97 return flags & ~FS_DIRSYNC_FL; 98 else 99 return flags & (FS_NODUMP_FL | FS_NOATIME_FL); 100 } 101 102 /* 103 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS 104 * ioctl. 105 */ 106 static unsigned int btrfs_inode_flags_to_fsflags(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_NOCOMPRESS) 126 iflags |= FS_NOCOMP_FL; 127 else if (flags & BTRFS_INODE_COMPRESS) 128 iflags |= FS_COMPR_FL; 129 130 return iflags; 131 } 132 133 /* 134 * Update inode->i_flags based on the btrfs internal flags. 135 */ 136 void btrfs_sync_inode_flags_to_i_flags(struct inode *inode) 137 { 138 struct btrfs_inode *binode = BTRFS_I(inode); 139 unsigned int new_fl = 0; 140 141 if (binode->flags & BTRFS_INODE_SYNC) 142 new_fl |= S_SYNC; 143 if (binode->flags & BTRFS_INODE_IMMUTABLE) 144 new_fl |= S_IMMUTABLE; 145 if (binode->flags & BTRFS_INODE_APPEND) 146 new_fl |= S_APPEND; 147 if (binode->flags & BTRFS_INODE_NOATIME) 148 new_fl |= S_NOATIME; 149 if (binode->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 static int btrfs_ioctl_getflags(struct file *file, void __user *arg) 158 { 159 struct btrfs_inode *binode = BTRFS_I(file_inode(file)); 160 unsigned int flags = btrfs_inode_flags_to_fsflags(binode->flags); 161 162 if (copy_to_user(arg, &flags, sizeof(flags))) 163 return -EFAULT; 164 return 0; 165 } 166 167 /* Check if @flags are a supported and valid set of FS_*_FL flags */ 168 static int check_fsflags(unsigned int flags) 169 { 170 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ 171 FS_NOATIME_FL | FS_NODUMP_FL | \ 172 FS_SYNC_FL | FS_DIRSYNC_FL | \ 173 FS_NOCOMP_FL | FS_COMPR_FL | 174 FS_NOCOW_FL)) 175 return -EOPNOTSUPP; 176 177 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) 178 return -EINVAL; 179 180 return 0; 181 } 182 183 static int btrfs_ioctl_setflags(struct file *file, void __user *arg) 184 { 185 struct inode *inode = file_inode(file); 186 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 187 struct btrfs_inode *binode = BTRFS_I(inode); 188 struct btrfs_root *root = binode->root; 189 struct btrfs_trans_handle *trans; 190 unsigned int fsflags, old_fsflags; 191 int ret; 192 u64 old_flags; 193 unsigned int old_i_flags; 194 umode_t mode; 195 196 if (!inode_owner_or_capable(inode)) 197 return -EPERM; 198 199 if (btrfs_root_readonly(root)) 200 return -EROFS; 201 202 if (copy_from_user(&fsflags, arg, sizeof(fsflags))) 203 return -EFAULT; 204 205 ret = check_fsflags(fsflags); 206 if (ret) 207 return ret; 208 209 ret = mnt_want_write_file(file); 210 if (ret) 211 return ret; 212 213 inode_lock(inode); 214 215 old_flags = binode->flags; 216 old_i_flags = inode->i_flags; 217 mode = inode->i_mode; 218 219 fsflags = btrfs_mask_fsflags_for_type(inode, fsflags); 220 old_fsflags = btrfs_inode_flags_to_fsflags(binode->flags); 221 if ((fsflags ^ old_fsflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { 222 if (!capable(CAP_LINUX_IMMUTABLE)) { 223 ret = -EPERM; 224 goto out_unlock; 225 } 226 } 227 228 if (fsflags & FS_SYNC_FL) 229 binode->flags |= BTRFS_INODE_SYNC; 230 else 231 binode->flags &= ~BTRFS_INODE_SYNC; 232 if (fsflags & FS_IMMUTABLE_FL) 233 binode->flags |= BTRFS_INODE_IMMUTABLE; 234 else 235 binode->flags &= ~BTRFS_INODE_IMMUTABLE; 236 if (fsflags & FS_APPEND_FL) 237 binode->flags |= BTRFS_INODE_APPEND; 238 else 239 binode->flags &= ~BTRFS_INODE_APPEND; 240 if (fsflags & FS_NODUMP_FL) 241 binode->flags |= BTRFS_INODE_NODUMP; 242 else 243 binode->flags &= ~BTRFS_INODE_NODUMP; 244 if (fsflags & FS_NOATIME_FL) 245 binode->flags |= BTRFS_INODE_NOATIME; 246 else 247 binode->flags &= ~BTRFS_INODE_NOATIME; 248 if (fsflags & FS_DIRSYNC_FL) 249 binode->flags |= BTRFS_INODE_DIRSYNC; 250 else 251 binode->flags &= ~BTRFS_INODE_DIRSYNC; 252 if (fsflags & FS_NOCOW_FL) { 253 if (S_ISREG(mode)) { 254 /* 255 * It's safe to turn csums off here, no extents exist. 256 * Otherwise we want the flag to reflect the real COW 257 * status of the file and will not set it. 258 */ 259 if (inode->i_size == 0) 260 binode->flags |= BTRFS_INODE_NODATACOW 261 | BTRFS_INODE_NODATASUM; 262 } else { 263 binode->flags |= BTRFS_INODE_NODATACOW; 264 } 265 } else { 266 /* 267 * Revert back under same assumptions as above 268 */ 269 if (S_ISREG(mode)) { 270 if (inode->i_size == 0) 271 binode->flags &= ~(BTRFS_INODE_NODATACOW 272 | BTRFS_INODE_NODATASUM); 273 } else { 274 binode->flags &= ~BTRFS_INODE_NODATACOW; 275 } 276 } 277 278 /* 279 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS 280 * flag may be changed automatically if compression code won't make 281 * things smaller. 282 */ 283 if (fsflags & FS_NOCOMP_FL) { 284 binode->flags &= ~BTRFS_INODE_COMPRESS; 285 binode->flags |= BTRFS_INODE_NOCOMPRESS; 286 287 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0); 288 if (ret && ret != -ENODATA) 289 goto out_drop; 290 } else if (fsflags & FS_COMPR_FL) { 291 const char *comp; 292 293 binode->flags |= BTRFS_INODE_COMPRESS; 294 binode->flags &= ~BTRFS_INODE_NOCOMPRESS; 295 296 comp = btrfs_compress_type2str(fs_info->compress_type); 297 if (!comp || comp[0] == 0) 298 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB); 299 300 ret = btrfs_set_prop(inode, "btrfs.compression", 301 comp, strlen(comp), 0); 302 if (ret) 303 goto out_drop; 304 305 } else { 306 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0); 307 if (ret && ret != -ENODATA) 308 goto out_drop; 309 binode->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); 310 } 311 312 trans = btrfs_start_transaction(root, 1); 313 if (IS_ERR(trans)) { 314 ret = PTR_ERR(trans); 315 goto out_drop; 316 } 317 318 btrfs_sync_inode_flags_to_i_flags(inode); 319 inode_inc_iversion(inode); 320 inode->i_ctime = current_time(inode); 321 ret = btrfs_update_inode(trans, root, inode); 322 323 btrfs_end_transaction(trans); 324 out_drop: 325 if (ret) { 326 binode->flags = old_flags; 327 inode->i_flags = old_i_flags; 328 } 329 330 out_unlock: 331 inode_unlock(inode); 332 mnt_drop_write_file(file); 333 return ret; 334 } 335 336 /* 337 * Translate btrfs internal inode flags to xflags as expected by the 338 * FS_IOC_FSGETXATT ioctl. Filter only the supported ones, unknown flags are 339 * silently dropped. 340 */ 341 static unsigned int btrfs_inode_flags_to_xflags(unsigned int flags) 342 { 343 unsigned int xflags = 0; 344 345 if (flags & BTRFS_INODE_APPEND) 346 xflags |= FS_XFLAG_APPEND; 347 if (flags & BTRFS_INODE_IMMUTABLE) 348 xflags |= FS_XFLAG_IMMUTABLE; 349 if (flags & BTRFS_INODE_NOATIME) 350 xflags |= FS_XFLAG_NOATIME; 351 if (flags & BTRFS_INODE_NODUMP) 352 xflags |= FS_XFLAG_NODUMP; 353 if (flags & BTRFS_INODE_SYNC) 354 xflags |= FS_XFLAG_SYNC; 355 356 return xflags; 357 } 358 359 /* Check if @flags are a supported and valid set of FS_XFLAGS_* flags */ 360 static int check_xflags(unsigned int flags) 361 { 362 if (flags & ~(FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE | FS_XFLAG_NOATIME | 363 FS_XFLAG_NODUMP | FS_XFLAG_SYNC)) 364 return -EOPNOTSUPP; 365 return 0; 366 } 367 368 /* 369 * Set the xflags from the internal inode flags. The remaining items of fsxattr 370 * are zeroed. 371 */ 372 static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg) 373 { 374 struct btrfs_inode *binode = BTRFS_I(file_inode(file)); 375 struct fsxattr fa; 376 377 memset(&fa, 0, sizeof(fa)); 378 fa.fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags); 379 380 if (copy_to_user(arg, &fa, sizeof(fa))) 381 return -EFAULT; 382 383 return 0; 384 } 385 386 static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg) 387 { 388 struct inode *inode = file_inode(file); 389 struct btrfs_inode *binode = BTRFS_I(inode); 390 struct btrfs_root *root = binode->root; 391 struct btrfs_trans_handle *trans; 392 struct fsxattr fa; 393 unsigned old_flags; 394 unsigned old_i_flags; 395 int ret = 0; 396 397 if (!inode_owner_or_capable(inode)) 398 return -EPERM; 399 400 if (btrfs_root_readonly(root)) 401 return -EROFS; 402 403 memset(&fa, 0, sizeof(fa)); 404 if (copy_from_user(&fa, arg, sizeof(fa))) 405 return -EFAULT; 406 407 ret = check_xflags(fa.fsx_xflags); 408 if (ret) 409 return ret; 410 411 if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0) 412 return -EOPNOTSUPP; 413 414 ret = mnt_want_write_file(file); 415 if (ret) 416 return ret; 417 418 inode_lock(inode); 419 420 old_flags = binode->flags; 421 old_i_flags = inode->i_flags; 422 423 /* We need the capabilities to change append-only or immutable inode */ 424 if (((old_flags & (BTRFS_INODE_APPEND | BTRFS_INODE_IMMUTABLE)) || 425 (fa.fsx_xflags & (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE))) && 426 !capable(CAP_LINUX_IMMUTABLE)) { 427 ret = -EPERM; 428 goto out_unlock; 429 } 430 431 if (fa.fsx_xflags & FS_XFLAG_SYNC) 432 binode->flags |= BTRFS_INODE_SYNC; 433 else 434 binode->flags &= ~BTRFS_INODE_SYNC; 435 if (fa.fsx_xflags & FS_XFLAG_IMMUTABLE) 436 binode->flags |= BTRFS_INODE_IMMUTABLE; 437 else 438 binode->flags &= ~BTRFS_INODE_IMMUTABLE; 439 if (fa.fsx_xflags & FS_XFLAG_APPEND) 440 binode->flags |= BTRFS_INODE_APPEND; 441 else 442 binode->flags &= ~BTRFS_INODE_APPEND; 443 if (fa.fsx_xflags & FS_XFLAG_NODUMP) 444 binode->flags |= BTRFS_INODE_NODUMP; 445 else 446 binode->flags &= ~BTRFS_INODE_NODUMP; 447 if (fa.fsx_xflags & FS_XFLAG_NOATIME) 448 binode->flags |= BTRFS_INODE_NOATIME; 449 else 450 binode->flags &= ~BTRFS_INODE_NOATIME; 451 452 /* 1 item for the inode */ 453 trans = btrfs_start_transaction(root, 1); 454 if (IS_ERR(trans)) { 455 ret = PTR_ERR(trans); 456 goto out_unlock; 457 } 458 459 btrfs_sync_inode_flags_to_i_flags(inode); 460 inode_inc_iversion(inode); 461 inode->i_ctime = current_time(inode); 462 ret = btrfs_update_inode(trans, root, inode); 463 464 btrfs_end_transaction(trans); 465 466 out_unlock: 467 if (ret) { 468 binode->flags = old_flags; 469 inode->i_flags = old_i_flags; 470 } 471 472 inode_unlock(inode); 473 mnt_drop_write_file(file); 474 475 return ret; 476 } 477 478 static int btrfs_ioctl_getversion(struct file *file, int __user *arg) 479 { 480 struct inode *inode = file_inode(file); 481 482 return put_user(inode->i_generation, arg); 483 } 484 485 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) 486 { 487 struct inode *inode = file_inode(file); 488 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 489 struct btrfs_device *device; 490 struct request_queue *q; 491 struct fstrim_range range; 492 u64 minlen = ULLONG_MAX; 493 u64 num_devices = 0; 494 int ret; 495 496 if (!capable(CAP_SYS_ADMIN)) 497 return -EPERM; 498 499 rcu_read_lock(); 500 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices, 501 dev_list) { 502 if (!device->bdev) 503 continue; 504 q = bdev_get_queue(device->bdev); 505 if (blk_queue_discard(q)) { 506 num_devices++; 507 minlen = min_t(u64, q->limits.discard_granularity, 508 minlen); 509 } 510 } 511 rcu_read_unlock(); 512 513 if (!num_devices) 514 return -EOPNOTSUPP; 515 if (copy_from_user(&range, arg, sizeof(range))) 516 return -EFAULT; 517 518 /* 519 * NOTE: Don't truncate the range using super->total_bytes. Bytenr of 520 * block group is in the logical address space, which can be any 521 * sectorsize aligned bytenr in the range [0, U64_MAX]. 522 */ 523 if (range.len < fs_info->sb->s_blocksize) 524 return -EINVAL; 525 526 range.minlen = max(range.minlen, minlen); 527 ret = btrfs_trim_fs(fs_info, &range); 528 if (ret < 0) 529 return ret; 530 531 if (copy_to_user(arg, &range, sizeof(range))) 532 return -EFAULT; 533 534 return 0; 535 } 536 537 int btrfs_is_empty_uuid(u8 *uuid) 538 { 539 int i; 540 541 for (i = 0; i < BTRFS_UUID_SIZE; i++) { 542 if (uuid[i]) 543 return 0; 544 } 545 return 1; 546 } 547 548 static noinline int create_subvol(struct inode *dir, 549 struct dentry *dentry, 550 const char *name, int namelen, 551 u64 *async_transid, 552 struct btrfs_qgroup_inherit *inherit) 553 { 554 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 555 struct btrfs_trans_handle *trans; 556 struct btrfs_key key; 557 struct btrfs_root_item *root_item; 558 struct btrfs_inode_item *inode_item; 559 struct extent_buffer *leaf; 560 struct btrfs_root *root = BTRFS_I(dir)->root; 561 struct btrfs_root *new_root; 562 struct btrfs_block_rsv block_rsv; 563 struct timespec64 cur_time = current_time(dir); 564 struct inode *inode; 565 int ret; 566 int err; 567 u64 objectid; 568 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; 569 u64 index = 0; 570 uuid_le new_uuid; 571 572 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL); 573 if (!root_item) 574 return -ENOMEM; 575 576 ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid); 577 if (ret) 578 goto fail_free; 579 580 /* 581 * Don't create subvolume whose level is not zero. Or qgroup will be 582 * screwed up since it assumes subvolume qgroup's level to be 0. 583 */ 584 if (btrfs_qgroup_level(objectid)) { 585 ret = -ENOSPC; 586 goto fail_free; 587 } 588 589 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); 590 /* 591 * The same as the snapshot creation, please see the comment 592 * of create_snapshot(). 593 */ 594 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false); 595 if (ret) 596 goto fail_free; 597 598 trans = btrfs_start_transaction(root, 0); 599 if (IS_ERR(trans)) { 600 ret = PTR_ERR(trans); 601 btrfs_subvolume_release_metadata(fs_info, &block_rsv); 602 goto fail_free; 603 } 604 trans->block_rsv = &block_rsv; 605 trans->bytes_reserved = block_rsv.size; 606 607 ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit); 608 if (ret) 609 goto fail; 610 611 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0); 612 if (IS_ERR(leaf)) { 613 ret = PTR_ERR(leaf); 614 goto fail; 615 } 616 617 btrfs_mark_buffer_dirty(leaf); 618 619 inode_item = &root_item->inode; 620 btrfs_set_stack_inode_generation(inode_item, 1); 621 btrfs_set_stack_inode_size(inode_item, 3); 622 btrfs_set_stack_inode_nlink(inode_item, 1); 623 btrfs_set_stack_inode_nbytes(inode_item, 624 fs_info->nodesize); 625 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); 626 627 btrfs_set_root_flags(root_item, 0); 628 btrfs_set_root_limit(root_item, 0); 629 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT); 630 631 btrfs_set_root_bytenr(root_item, leaf->start); 632 btrfs_set_root_generation(root_item, trans->transid); 633 btrfs_set_root_level(root_item, 0); 634 btrfs_set_root_refs(root_item, 1); 635 btrfs_set_root_used(root_item, leaf->len); 636 btrfs_set_root_last_snapshot(root_item, 0); 637 638 btrfs_set_root_generation_v2(root_item, 639 btrfs_root_generation(root_item)); 640 uuid_le_gen(&new_uuid); 641 memcpy(root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE); 642 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec); 643 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec); 644 root_item->ctime = root_item->otime; 645 btrfs_set_root_ctransid(root_item, trans->transid); 646 btrfs_set_root_otransid(root_item, trans->transid); 647 648 btrfs_tree_unlock(leaf); 649 free_extent_buffer(leaf); 650 leaf = NULL; 651 652 btrfs_set_root_dirid(root_item, new_dirid); 653 654 key.objectid = objectid; 655 key.offset = 0; 656 key.type = BTRFS_ROOT_ITEM_KEY; 657 ret = btrfs_insert_root(trans, fs_info->tree_root, &key, 658 root_item); 659 if (ret) 660 goto fail; 661 662 key.offset = (u64)-1; 663 new_root = btrfs_read_fs_root_no_name(fs_info, &key); 664 if (IS_ERR(new_root)) { 665 ret = PTR_ERR(new_root); 666 btrfs_abort_transaction(trans, ret); 667 goto fail; 668 } 669 670 btrfs_record_root_in_trans(trans, new_root); 671 672 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid); 673 if (ret) { 674 /* We potentially lose an unused inode item here */ 675 btrfs_abort_transaction(trans, ret); 676 goto fail; 677 } 678 679 mutex_lock(&new_root->objectid_mutex); 680 new_root->highest_objectid = new_dirid; 681 mutex_unlock(&new_root->objectid_mutex); 682 683 /* 684 * insert the directory item 685 */ 686 ret = btrfs_set_inode_index(BTRFS_I(dir), &index); 687 if (ret) { 688 btrfs_abort_transaction(trans, ret); 689 goto fail; 690 } 691 692 ret = btrfs_insert_dir_item(trans, name, namelen, BTRFS_I(dir), &key, 693 BTRFS_FT_DIR, index); 694 if (ret) { 695 btrfs_abort_transaction(trans, ret); 696 goto fail; 697 } 698 699 btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2); 700 ret = btrfs_update_inode(trans, root, dir); 701 BUG_ON(ret); 702 703 ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid, 704 btrfs_ino(BTRFS_I(dir)), index, name, namelen); 705 BUG_ON(ret); 706 707 ret = btrfs_uuid_tree_add(trans, root_item->uuid, 708 BTRFS_UUID_KEY_SUBVOL, objectid); 709 if (ret) 710 btrfs_abort_transaction(trans, ret); 711 712 fail: 713 kfree(root_item); 714 trans->block_rsv = NULL; 715 trans->bytes_reserved = 0; 716 btrfs_subvolume_release_metadata(fs_info, &block_rsv); 717 718 if (async_transid) { 719 *async_transid = trans->transid; 720 err = btrfs_commit_transaction_async(trans, 1); 721 if (err) 722 err = btrfs_commit_transaction(trans); 723 } else { 724 err = btrfs_commit_transaction(trans); 725 } 726 if (err && !ret) 727 ret = err; 728 729 if (!ret) { 730 inode = btrfs_lookup_dentry(dir, dentry); 731 if (IS_ERR(inode)) 732 return PTR_ERR(inode); 733 d_instantiate(dentry, inode); 734 } 735 return ret; 736 737 fail_free: 738 kfree(root_item); 739 return ret; 740 } 741 742 static int create_snapshot(struct btrfs_root *root, struct inode *dir, 743 struct dentry *dentry, 744 u64 *async_transid, bool readonly, 745 struct btrfs_qgroup_inherit *inherit) 746 { 747 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 748 struct inode *inode; 749 struct btrfs_pending_snapshot *pending_snapshot; 750 struct btrfs_trans_handle *trans; 751 int ret; 752 bool snapshot_force_cow = false; 753 754 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 755 return -EINVAL; 756 757 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL); 758 if (!pending_snapshot) 759 return -ENOMEM; 760 761 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item), 762 GFP_KERNEL); 763 pending_snapshot->path = btrfs_alloc_path(); 764 if (!pending_snapshot->root_item || !pending_snapshot->path) { 765 ret = -ENOMEM; 766 goto free_pending; 767 } 768 769 /* 770 * Force new buffered writes to reserve space even when NOCOW is 771 * possible. This is to avoid later writeback (running dealloc) to 772 * fallback to COW mode and unexpectedly fail with ENOSPC. 773 */ 774 atomic_inc(&root->will_be_snapshotted); 775 smp_mb__after_atomic(); 776 /* wait for no snapshot writes */ 777 wait_event(root->subv_writers->wait, 778 percpu_counter_sum(&root->subv_writers->counter) == 0); 779 780 ret = btrfs_start_delalloc_inodes(root); 781 if (ret) 782 goto dec_and_free; 783 784 /* 785 * All previous writes have started writeback in NOCOW mode, so now 786 * we force future writes to fallback to COW mode during snapshot 787 * creation. 788 */ 789 atomic_inc(&root->snapshot_force_cow); 790 snapshot_force_cow = true; 791 792 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1); 793 794 btrfs_init_block_rsv(&pending_snapshot->block_rsv, 795 BTRFS_BLOCK_RSV_TEMP); 796 /* 797 * 1 - parent dir inode 798 * 2 - dir entries 799 * 1 - root item 800 * 2 - root ref/backref 801 * 1 - root of snapshot 802 * 1 - UUID item 803 */ 804 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, 805 &pending_snapshot->block_rsv, 8, 806 false); 807 if (ret) 808 goto dec_and_free; 809 810 pending_snapshot->dentry = dentry; 811 pending_snapshot->root = root; 812 pending_snapshot->readonly = readonly; 813 pending_snapshot->dir = dir; 814 pending_snapshot->inherit = inherit; 815 816 trans = btrfs_start_transaction(root, 0); 817 if (IS_ERR(trans)) { 818 ret = PTR_ERR(trans); 819 goto fail; 820 } 821 822 spin_lock(&fs_info->trans_lock); 823 list_add(&pending_snapshot->list, 824 &trans->transaction->pending_snapshots); 825 spin_unlock(&fs_info->trans_lock); 826 if (async_transid) { 827 *async_transid = trans->transid; 828 ret = btrfs_commit_transaction_async(trans, 1); 829 if (ret) 830 ret = btrfs_commit_transaction(trans); 831 } else { 832 ret = btrfs_commit_transaction(trans); 833 } 834 if (ret) 835 goto fail; 836 837 ret = pending_snapshot->error; 838 if (ret) 839 goto fail; 840 841 ret = btrfs_orphan_cleanup(pending_snapshot->snap); 842 if (ret) 843 goto fail; 844 845 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry); 846 if (IS_ERR(inode)) { 847 ret = PTR_ERR(inode); 848 goto fail; 849 } 850 851 d_instantiate(dentry, inode); 852 ret = 0; 853 fail: 854 btrfs_subvolume_release_metadata(fs_info, &pending_snapshot->block_rsv); 855 dec_and_free: 856 if (snapshot_force_cow) 857 atomic_dec(&root->snapshot_force_cow); 858 if (atomic_dec_and_test(&root->will_be_snapshotted)) 859 wake_up_var(&root->will_be_snapshotted); 860 free_pending: 861 kfree(pending_snapshot->root_item); 862 btrfs_free_path(pending_snapshot->path); 863 kfree(pending_snapshot); 864 865 return ret; 866 } 867 868 /* copy of may_delete in fs/namei.c() 869 * Check whether we can remove a link victim from directory dir, check 870 * whether the type of victim is right. 871 * 1. We can't do it if dir is read-only (done in permission()) 872 * 2. We should have write and exec permissions on dir 873 * 3. We can't remove anything from append-only dir 874 * 4. We can't do anything with immutable dir (done in permission()) 875 * 5. If the sticky bit on dir is set we should either 876 * a. be owner of dir, or 877 * b. be owner of victim, or 878 * c. have CAP_FOWNER capability 879 * 6. If the victim is append-only or immutable we can't do anything with 880 * links pointing to it. 881 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. 882 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. 883 * 9. We can't remove a root or mountpoint. 884 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by 885 * nfs_async_unlink(). 886 */ 887 888 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir) 889 { 890 int error; 891 892 if (d_really_is_negative(victim)) 893 return -ENOENT; 894 895 BUG_ON(d_inode(victim->d_parent) != dir); 896 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); 897 898 error = inode_permission(dir, MAY_WRITE | MAY_EXEC); 899 if (error) 900 return error; 901 if (IS_APPEND(dir)) 902 return -EPERM; 903 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) || 904 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim))) 905 return -EPERM; 906 if (isdir) { 907 if (!d_is_dir(victim)) 908 return -ENOTDIR; 909 if (IS_ROOT(victim)) 910 return -EBUSY; 911 } else if (d_is_dir(victim)) 912 return -EISDIR; 913 if (IS_DEADDIR(dir)) 914 return -ENOENT; 915 if (victim->d_flags & DCACHE_NFSFS_RENAMED) 916 return -EBUSY; 917 return 0; 918 } 919 920 /* copy of may_create in fs/namei.c() */ 921 static inline int btrfs_may_create(struct inode *dir, struct dentry *child) 922 { 923 if (d_really_is_positive(child)) 924 return -EEXIST; 925 if (IS_DEADDIR(dir)) 926 return -ENOENT; 927 return inode_permission(dir, MAY_WRITE | MAY_EXEC); 928 } 929 930 /* 931 * Create a new subvolume below @parent. This is largely modeled after 932 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup 933 * inside this filesystem so it's quite a bit simpler. 934 */ 935 static noinline int btrfs_mksubvol(const struct path *parent, 936 const char *name, int namelen, 937 struct btrfs_root *snap_src, 938 u64 *async_transid, bool readonly, 939 struct btrfs_qgroup_inherit *inherit) 940 { 941 struct inode *dir = d_inode(parent->dentry); 942 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 943 struct dentry *dentry; 944 int error; 945 946 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT); 947 if (error == -EINTR) 948 return error; 949 950 dentry = lookup_one_len(name, parent->dentry, namelen); 951 error = PTR_ERR(dentry); 952 if (IS_ERR(dentry)) 953 goto out_unlock; 954 955 error = btrfs_may_create(dir, dentry); 956 if (error) 957 goto out_dput; 958 959 /* 960 * even if this name doesn't exist, we may get hash collisions. 961 * check for them now when we can safely fail 962 */ 963 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root, 964 dir->i_ino, name, 965 namelen); 966 if (error) 967 goto out_dput; 968 969 down_read(&fs_info->subvol_sem); 970 971 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) 972 goto out_up_read; 973 974 if (snap_src) { 975 error = create_snapshot(snap_src, dir, dentry, 976 async_transid, readonly, inherit); 977 } else { 978 error = create_subvol(dir, dentry, name, namelen, 979 async_transid, inherit); 980 } 981 if (!error) 982 fsnotify_mkdir(dir, dentry); 983 out_up_read: 984 up_read(&fs_info->subvol_sem); 985 out_dput: 986 dput(dentry); 987 out_unlock: 988 inode_unlock(dir); 989 return error; 990 } 991 992 /* 993 * When we're defragging a range, we don't want to kick it off again 994 * if it is really just waiting for delalloc to send it down. 995 * If we find a nice big extent or delalloc range for the bytes in the 996 * file you want to defrag, we return 0 to let you know to skip this 997 * part of the file 998 */ 999 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh) 1000 { 1001 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 1002 struct extent_map *em = NULL; 1003 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 1004 u64 end; 1005 1006 read_lock(&em_tree->lock); 1007 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE); 1008 read_unlock(&em_tree->lock); 1009 1010 if (em) { 1011 end = extent_map_end(em); 1012 free_extent_map(em); 1013 if (end - offset > thresh) 1014 return 0; 1015 } 1016 /* if we already have a nice delalloc here, just stop */ 1017 thresh /= 2; 1018 end = count_range_bits(io_tree, &offset, offset + thresh, 1019 thresh, EXTENT_DELALLOC, 1); 1020 if (end >= thresh) 1021 return 0; 1022 return 1; 1023 } 1024 1025 /* 1026 * helper function to walk through a file and find extents 1027 * newer than a specific transid, and smaller than thresh. 1028 * 1029 * This is used by the defragging code to find new and small 1030 * extents 1031 */ 1032 static int find_new_extents(struct btrfs_root *root, 1033 struct inode *inode, u64 newer_than, 1034 u64 *off, u32 thresh) 1035 { 1036 struct btrfs_path *path; 1037 struct btrfs_key min_key; 1038 struct extent_buffer *leaf; 1039 struct btrfs_file_extent_item *extent; 1040 int type; 1041 int ret; 1042 u64 ino = btrfs_ino(BTRFS_I(inode)); 1043 1044 path = btrfs_alloc_path(); 1045 if (!path) 1046 return -ENOMEM; 1047 1048 min_key.objectid = ino; 1049 min_key.type = BTRFS_EXTENT_DATA_KEY; 1050 min_key.offset = *off; 1051 1052 while (1) { 1053 ret = btrfs_search_forward(root, &min_key, path, newer_than); 1054 if (ret != 0) 1055 goto none; 1056 process_slot: 1057 if (min_key.objectid != ino) 1058 goto none; 1059 if (min_key.type != BTRFS_EXTENT_DATA_KEY) 1060 goto none; 1061 1062 leaf = path->nodes[0]; 1063 extent = btrfs_item_ptr(leaf, path->slots[0], 1064 struct btrfs_file_extent_item); 1065 1066 type = btrfs_file_extent_type(leaf, extent); 1067 if (type == BTRFS_FILE_EXTENT_REG && 1068 btrfs_file_extent_num_bytes(leaf, extent) < thresh && 1069 check_defrag_in_cache(inode, min_key.offset, thresh)) { 1070 *off = min_key.offset; 1071 btrfs_free_path(path); 1072 return 0; 1073 } 1074 1075 path->slots[0]++; 1076 if (path->slots[0] < btrfs_header_nritems(leaf)) { 1077 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]); 1078 goto process_slot; 1079 } 1080 1081 if (min_key.offset == (u64)-1) 1082 goto none; 1083 1084 min_key.offset++; 1085 btrfs_release_path(path); 1086 } 1087 none: 1088 btrfs_free_path(path); 1089 return -ENOENT; 1090 } 1091 1092 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start) 1093 { 1094 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 1095 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 1096 struct extent_map *em; 1097 u64 len = PAGE_SIZE; 1098 1099 /* 1100 * hopefully we have this extent in the tree already, try without 1101 * the full extent lock 1102 */ 1103 read_lock(&em_tree->lock); 1104 em = lookup_extent_mapping(em_tree, start, len); 1105 read_unlock(&em_tree->lock); 1106 1107 if (!em) { 1108 struct extent_state *cached = NULL; 1109 u64 end = start + len - 1; 1110 1111 /* get the big lock and read metadata off disk */ 1112 lock_extent_bits(io_tree, start, end, &cached); 1113 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0); 1114 unlock_extent_cached(io_tree, start, end, &cached); 1115 1116 if (IS_ERR(em)) 1117 return NULL; 1118 } 1119 1120 return em; 1121 } 1122 1123 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) 1124 { 1125 struct extent_map *next; 1126 bool ret = true; 1127 1128 /* this is the last extent */ 1129 if (em->start + em->len >= i_size_read(inode)) 1130 return false; 1131 1132 next = defrag_lookup_extent(inode, em->start + em->len); 1133 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) 1134 ret = false; 1135 else if ((em->block_start + em->block_len == next->block_start) && 1136 (em->block_len > SZ_128K && next->block_len > SZ_128K)) 1137 ret = false; 1138 1139 free_extent_map(next); 1140 return ret; 1141 } 1142 1143 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh, 1144 u64 *last_len, u64 *skip, u64 *defrag_end, 1145 int compress) 1146 { 1147 struct extent_map *em; 1148 int ret = 1; 1149 bool next_mergeable = true; 1150 bool prev_mergeable = true; 1151 1152 /* 1153 * make sure that once we start defragging an extent, we keep on 1154 * defragging it 1155 */ 1156 if (start < *defrag_end) 1157 return 1; 1158 1159 *skip = 0; 1160 1161 em = defrag_lookup_extent(inode, start); 1162 if (!em) 1163 return 0; 1164 1165 /* this will cover holes, and inline extents */ 1166 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 1167 ret = 0; 1168 goto out; 1169 } 1170 1171 if (!*defrag_end) 1172 prev_mergeable = false; 1173 1174 next_mergeable = defrag_check_next_extent(inode, em); 1175 /* 1176 * we hit a real extent, if it is big or the next extent is not a 1177 * real extent, don't bother defragging it 1178 */ 1179 if (!compress && (*last_len == 0 || *last_len >= thresh) && 1180 (em->len >= thresh || (!next_mergeable && !prev_mergeable))) 1181 ret = 0; 1182 out: 1183 /* 1184 * last_len ends up being a counter of how many bytes we've defragged. 1185 * every time we choose not to defrag an extent, we reset *last_len 1186 * so that the next tiny extent will force a defrag. 1187 * 1188 * The end result of this is that tiny extents before a single big 1189 * extent will force at least part of that big extent to be defragged. 1190 */ 1191 if (ret) { 1192 *defrag_end = extent_map_end(em); 1193 } else { 1194 *last_len = 0; 1195 *skip = extent_map_end(em); 1196 *defrag_end = 0; 1197 } 1198 1199 free_extent_map(em); 1200 return ret; 1201 } 1202 1203 /* 1204 * it doesn't do much good to defrag one or two pages 1205 * at a time. This pulls in a nice chunk of pages 1206 * to COW and defrag. 1207 * 1208 * It also makes sure the delalloc code has enough 1209 * dirty data to avoid making new small extents as part 1210 * of the defrag 1211 * 1212 * It's a good idea to start RA on this range 1213 * before calling this. 1214 */ 1215 static int cluster_pages_for_defrag(struct inode *inode, 1216 struct page **pages, 1217 unsigned long start_index, 1218 unsigned long num_pages) 1219 { 1220 unsigned long file_end; 1221 u64 isize = i_size_read(inode); 1222 u64 page_start; 1223 u64 page_end; 1224 u64 page_cnt; 1225 int ret; 1226 int i; 1227 int i_done; 1228 struct btrfs_ordered_extent *ordered; 1229 struct extent_state *cached_state = NULL; 1230 struct extent_io_tree *tree; 1231 struct extent_changeset *data_reserved = NULL; 1232 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 1233 1234 file_end = (isize - 1) >> PAGE_SHIFT; 1235 if (!isize || start_index > file_end) 1236 return 0; 1237 1238 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); 1239 1240 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, 1241 start_index << PAGE_SHIFT, 1242 page_cnt << PAGE_SHIFT); 1243 if (ret) 1244 return ret; 1245 i_done = 0; 1246 tree = &BTRFS_I(inode)->io_tree; 1247 1248 /* step one, lock all the pages */ 1249 for (i = 0; i < page_cnt; i++) { 1250 struct page *page; 1251 again: 1252 page = find_or_create_page(inode->i_mapping, 1253 start_index + i, mask); 1254 if (!page) 1255 break; 1256 1257 page_start = page_offset(page); 1258 page_end = page_start + PAGE_SIZE - 1; 1259 while (1) { 1260 lock_extent_bits(tree, page_start, page_end, 1261 &cached_state); 1262 ordered = btrfs_lookup_ordered_extent(inode, 1263 page_start); 1264 unlock_extent_cached(tree, page_start, page_end, 1265 &cached_state); 1266 if (!ordered) 1267 break; 1268 1269 unlock_page(page); 1270 btrfs_start_ordered_extent(inode, ordered, 1); 1271 btrfs_put_ordered_extent(ordered); 1272 lock_page(page); 1273 /* 1274 * we unlocked the page above, so we need check if 1275 * it was released or not. 1276 */ 1277 if (page->mapping != inode->i_mapping) { 1278 unlock_page(page); 1279 put_page(page); 1280 goto again; 1281 } 1282 } 1283 1284 if (!PageUptodate(page)) { 1285 btrfs_readpage(NULL, page); 1286 lock_page(page); 1287 if (!PageUptodate(page)) { 1288 unlock_page(page); 1289 put_page(page); 1290 ret = -EIO; 1291 break; 1292 } 1293 } 1294 1295 if (page->mapping != inode->i_mapping) { 1296 unlock_page(page); 1297 put_page(page); 1298 goto again; 1299 } 1300 1301 pages[i] = page; 1302 i_done++; 1303 } 1304 if (!i_done || ret) 1305 goto out; 1306 1307 if (!(inode->i_sb->s_flags & SB_ACTIVE)) 1308 goto out; 1309 1310 /* 1311 * so now we have a nice long stream of locked 1312 * and up to date pages, lets wait on them 1313 */ 1314 for (i = 0; i < i_done; i++) 1315 wait_on_page_writeback(pages[i]); 1316 1317 page_start = page_offset(pages[0]); 1318 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE; 1319 1320 lock_extent_bits(&BTRFS_I(inode)->io_tree, 1321 page_start, page_end - 1, &cached_state); 1322 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, 1323 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | 1324 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, 1325 &cached_state); 1326 1327 if (i_done != page_cnt) { 1328 spin_lock(&BTRFS_I(inode)->lock); 1329 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1); 1330 spin_unlock(&BTRFS_I(inode)->lock); 1331 btrfs_delalloc_release_space(inode, data_reserved, 1332 start_index << PAGE_SHIFT, 1333 (page_cnt - i_done) << PAGE_SHIFT, true); 1334 } 1335 1336 1337 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, 1338 &cached_state); 1339 1340 unlock_extent_cached(&BTRFS_I(inode)->io_tree, 1341 page_start, page_end - 1, &cached_state); 1342 1343 for (i = 0; i < i_done; i++) { 1344 clear_page_dirty_for_io(pages[i]); 1345 ClearPageChecked(pages[i]); 1346 set_page_extent_mapped(pages[i]); 1347 set_page_dirty(pages[i]); 1348 unlock_page(pages[i]); 1349 put_page(pages[i]); 1350 } 1351 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT, 1352 false); 1353 extent_changeset_free(data_reserved); 1354 return i_done; 1355 out: 1356 for (i = 0; i < i_done; i++) { 1357 unlock_page(pages[i]); 1358 put_page(pages[i]); 1359 } 1360 btrfs_delalloc_release_space(inode, data_reserved, 1361 start_index << PAGE_SHIFT, 1362 page_cnt << PAGE_SHIFT, true); 1363 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT, 1364 true); 1365 extent_changeset_free(data_reserved); 1366 return ret; 1367 1368 } 1369 1370 int btrfs_defrag_file(struct inode *inode, struct file *file, 1371 struct btrfs_ioctl_defrag_range_args *range, 1372 u64 newer_than, unsigned long max_to_defrag) 1373 { 1374 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1375 struct btrfs_root *root = BTRFS_I(inode)->root; 1376 struct file_ra_state *ra = NULL; 1377 unsigned long last_index; 1378 u64 isize = i_size_read(inode); 1379 u64 last_len = 0; 1380 u64 skip = 0; 1381 u64 defrag_end = 0; 1382 u64 newer_off = range->start; 1383 unsigned long i; 1384 unsigned long ra_index = 0; 1385 int ret; 1386 int defrag_count = 0; 1387 int compress_type = BTRFS_COMPRESS_ZLIB; 1388 u32 extent_thresh = range->extent_thresh; 1389 unsigned long max_cluster = SZ_256K >> PAGE_SHIFT; 1390 unsigned long cluster = max_cluster; 1391 u64 new_align = ~((u64)SZ_128K - 1); 1392 struct page **pages = NULL; 1393 bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS; 1394 1395 if (isize == 0) 1396 return 0; 1397 1398 if (range->start >= isize) 1399 return -EINVAL; 1400 1401 if (do_compress) { 1402 if (range->compress_type > BTRFS_COMPRESS_TYPES) 1403 return -EINVAL; 1404 if (range->compress_type) 1405 compress_type = range->compress_type; 1406 } 1407 1408 if (extent_thresh == 0) 1409 extent_thresh = SZ_256K; 1410 1411 /* 1412 * If we were not given a file, allocate a readahead context. As 1413 * readahead is just an optimization, defrag will work without it so 1414 * we don't error out. 1415 */ 1416 if (!file) { 1417 ra = kzalloc(sizeof(*ra), GFP_KERNEL); 1418 if (ra) 1419 file_ra_state_init(ra, inode->i_mapping); 1420 } else { 1421 ra = &file->f_ra; 1422 } 1423 1424 pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL); 1425 if (!pages) { 1426 ret = -ENOMEM; 1427 goto out_ra; 1428 } 1429 1430 /* find the last page to defrag */ 1431 if (range->start + range->len > range->start) { 1432 last_index = min_t(u64, isize - 1, 1433 range->start + range->len - 1) >> PAGE_SHIFT; 1434 } else { 1435 last_index = (isize - 1) >> PAGE_SHIFT; 1436 } 1437 1438 if (newer_than) { 1439 ret = find_new_extents(root, inode, newer_than, 1440 &newer_off, SZ_64K); 1441 if (!ret) { 1442 range->start = newer_off; 1443 /* 1444 * we always align our defrag to help keep 1445 * the extents in the file evenly spaced 1446 */ 1447 i = (newer_off & new_align) >> PAGE_SHIFT; 1448 } else 1449 goto out_ra; 1450 } else { 1451 i = range->start >> PAGE_SHIFT; 1452 } 1453 if (!max_to_defrag) 1454 max_to_defrag = last_index - i + 1; 1455 1456 /* 1457 * make writeback starts from i, so the defrag range can be 1458 * written sequentially. 1459 */ 1460 if (i < inode->i_mapping->writeback_index) 1461 inode->i_mapping->writeback_index = i; 1462 1463 while (i <= last_index && defrag_count < max_to_defrag && 1464 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) { 1465 /* 1466 * make sure we stop running if someone unmounts 1467 * the FS 1468 */ 1469 if (!(inode->i_sb->s_flags & SB_ACTIVE)) 1470 break; 1471 1472 if (btrfs_defrag_cancelled(fs_info)) { 1473 btrfs_debug(fs_info, "defrag_file cancelled"); 1474 ret = -EAGAIN; 1475 break; 1476 } 1477 1478 if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT, 1479 extent_thresh, &last_len, &skip, 1480 &defrag_end, do_compress)){ 1481 unsigned long next; 1482 /* 1483 * the should_defrag function tells us how much to skip 1484 * bump our counter by the suggested amount 1485 */ 1486 next = DIV_ROUND_UP(skip, PAGE_SIZE); 1487 i = max(i + 1, next); 1488 continue; 1489 } 1490 1491 if (!newer_than) { 1492 cluster = (PAGE_ALIGN(defrag_end) >> 1493 PAGE_SHIFT) - i; 1494 cluster = min(cluster, max_cluster); 1495 } else { 1496 cluster = max_cluster; 1497 } 1498 1499 if (i + cluster > ra_index) { 1500 ra_index = max(i, ra_index); 1501 if (ra) 1502 page_cache_sync_readahead(inode->i_mapping, ra, 1503 file, ra_index, cluster); 1504 ra_index += cluster; 1505 } 1506 1507 inode_lock(inode); 1508 if (do_compress) 1509 BTRFS_I(inode)->defrag_compress = compress_type; 1510 ret = cluster_pages_for_defrag(inode, pages, i, cluster); 1511 if (ret < 0) { 1512 inode_unlock(inode); 1513 goto out_ra; 1514 } 1515 1516 defrag_count += ret; 1517 balance_dirty_pages_ratelimited(inode->i_mapping); 1518 inode_unlock(inode); 1519 1520 if (newer_than) { 1521 if (newer_off == (u64)-1) 1522 break; 1523 1524 if (ret > 0) 1525 i += ret; 1526 1527 newer_off = max(newer_off + 1, 1528 (u64)i << PAGE_SHIFT); 1529 1530 ret = find_new_extents(root, inode, newer_than, 1531 &newer_off, SZ_64K); 1532 if (!ret) { 1533 range->start = newer_off; 1534 i = (newer_off & new_align) >> PAGE_SHIFT; 1535 } else { 1536 break; 1537 } 1538 } else { 1539 if (ret > 0) { 1540 i += ret; 1541 last_len += ret << PAGE_SHIFT; 1542 } else { 1543 i++; 1544 last_len = 0; 1545 } 1546 } 1547 } 1548 1549 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) { 1550 filemap_flush(inode->i_mapping); 1551 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 1552 &BTRFS_I(inode)->runtime_flags)) 1553 filemap_flush(inode->i_mapping); 1554 } 1555 1556 if (range->compress_type == BTRFS_COMPRESS_LZO) { 1557 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO); 1558 } else if (range->compress_type == BTRFS_COMPRESS_ZSTD) { 1559 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD); 1560 } 1561 1562 ret = defrag_count; 1563 1564 out_ra: 1565 if (do_compress) { 1566 inode_lock(inode); 1567 BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE; 1568 inode_unlock(inode); 1569 } 1570 if (!file) 1571 kfree(ra); 1572 kfree(pages); 1573 return ret; 1574 } 1575 1576 static noinline int btrfs_ioctl_resize(struct file *file, 1577 void __user *arg) 1578 { 1579 struct inode *inode = file_inode(file); 1580 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1581 u64 new_size; 1582 u64 old_size; 1583 u64 devid = 1; 1584 struct btrfs_root *root = BTRFS_I(inode)->root; 1585 struct btrfs_ioctl_vol_args *vol_args; 1586 struct btrfs_trans_handle *trans; 1587 struct btrfs_device *device = NULL; 1588 char *sizestr; 1589 char *retptr; 1590 char *devstr = NULL; 1591 int ret = 0; 1592 int mod = 0; 1593 1594 if (!capable(CAP_SYS_ADMIN)) 1595 return -EPERM; 1596 1597 ret = mnt_want_write_file(file); 1598 if (ret) 1599 return ret; 1600 1601 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { 1602 mnt_drop_write_file(file); 1603 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 1604 } 1605 1606 vol_args = memdup_user(arg, sizeof(*vol_args)); 1607 if (IS_ERR(vol_args)) { 1608 ret = PTR_ERR(vol_args); 1609 goto out; 1610 } 1611 1612 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1613 1614 sizestr = vol_args->name; 1615 devstr = strchr(sizestr, ':'); 1616 if (devstr) { 1617 sizestr = devstr + 1; 1618 *devstr = '\0'; 1619 devstr = vol_args->name; 1620 ret = kstrtoull(devstr, 10, &devid); 1621 if (ret) 1622 goto out_free; 1623 if (!devid) { 1624 ret = -EINVAL; 1625 goto out_free; 1626 } 1627 btrfs_info(fs_info, "resizing devid %llu", devid); 1628 } 1629 1630 device = btrfs_find_device(fs_info, devid, NULL, NULL); 1631 if (!device) { 1632 btrfs_info(fs_info, "resizer unable to find device %llu", 1633 devid); 1634 ret = -ENODEV; 1635 goto out_free; 1636 } 1637 1638 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { 1639 btrfs_info(fs_info, 1640 "resizer unable to apply on readonly device %llu", 1641 devid); 1642 ret = -EPERM; 1643 goto out_free; 1644 } 1645 1646 if (!strcmp(sizestr, "max")) 1647 new_size = device->bdev->bd_inode->i_size; 1648 else { 1649 if (sizestr[0] == '-') { 1650 mod = -1; 1651 sizestr++; 1652 } else if (sizestr[0] == '+') { 1653 mod = 1; 1654 sizestr++; 1655 } 1656 new_size = memparse(sizestr, &retptr); 1657 if (*retptr != '\0' || new_size == 0) { 1658 ret = -EINVAL; 1659 goto out_free; 1660 } 1661 } 1662 1663 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { 1664 ret = -EPERM; 1665 goto out_free; 1666 } 1667 1668 old_size = btrfs_device_get_total_bytes(device); 1669 1670 if (mod < 0) { 1671 if (new_size > old_size) { 1672 ret = -EINVAL; 1673 goto out_free; 1674 } 1675 new_size = old_size - new_size; 1676 } else if (mod > 0) { 1677 if (new_size > ULLONG_MAX - old_size) { 1678 ret = -ERANGE; 1679 goto out_free; 1680 } 1681 new_size = old_size + new_size; 1682 } 1683 1684 if (new_size < SZ_256M) { 1685 ret = -EINVAL; 1686 goto out_free; 1687 } 1688 if (new_size > device->bdev->bd_inode->i_size) { 1689 ret = -EFBIG; 1690 goto out_free; 1691 } 1692 1693 new_size = round_down(new_size, fs_info->sectorsize); 1694 1695 btrfs_info_in_rcu(fs_info, "new size for %s is %llu", 1696 rcu_str_deref(device->name), new_size); 1697 1698 if (new_size > old_size) { 1699 trans = btrfs_start_transaction(root, 0); 1700 if (IS_ERR(trans)) { 1701 ret = PTR_ERR(trans); 1702 goto out_free; 1703 } 1704 ret = btrfs_grow_device(trans, device, new_size); 1705 btrfs_commit_transaction(trans); 1706 } else if (new_size < old_size) { 1707 ret = btrfs_shrink_device(device, new_size); 1708 } /* equal, nothing need to do */ 1709 1710 out_free: 1711 kfree(vol_args); 1712 out: 1713 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 1714 mnt_drop_write_file(file); 1715 return ret; 1716 } 1717 1718 static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 1719 const char *name, unsigned long fd, int subvol, 1720 u64 *transid, bool readonly, 1721 struct btrfs_qgroup_inherit *inherit) 1722 { 1723 int namelen; 1724 int ret = 0; 1725 1726 if (!S_ISDIR(file_inode(file)->i_mode)) 1727 return -ENOTDIR; 1728 1729 ret = mnt_want_write_file(file); 1730 if (ret) 1731 goto out; 1732 1733 namelen = strlen(name); 1734 if (strchr(name, '/')) { 1735 ret = -EINVAL; 1736 goto out_drop_write; 1737 } 1738 1739 if (name[0] == '.' && 1740 (namelen == 1 || (name[1] == '.' && namelen == 2))) { 1741 ret = -EEXIST; 1742 goto out_drop_write; 1743 } 1744 1745 if (subvol) { 1746 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1747 NULL, transid, readonly, inherit); 1748 } else { 1749 struct fd src = fdget(fd); 1750 struct inode *src_inode; 1751 if (!src.file) { 1752 ret = -EINVAL; 1753 goto out_drop_write; 1754 } 1755 1756 src_inode = file_inode(src.file); 1757 if (src_inode->i_sb != file_inode(file)->i_sb) { 1758 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info, 1759 "Snapshot src from another FS"); 1760 ret = -EXDEV; 1761 } else if (!inode_owner_or_capable(src_inode)) { 1762 /* 1763 * Subvolume creation is not restricted, but snapshots 1764 * are limited to own subvolumes only 1765 */ 1766 ret = -EPERM; 1767 } else { 1768 ret = btrfs_mksubvol(&file->f_path, name, namelen, 1769 BTRFS_I(src_inode)->root, 1770 transid, readonly, inherit); 1771 } 1772 fdput(src); 1773 } 1774 out_drop_write: 1775 mnt_drop_write_file(file); 1776 out: 1777 return ret; 1778 } 1779 1780 static noinline int btrfs_ioctl_snap_create(struct file *file, 1781 void __user *arg, int subvol) 1782 { 1783 struct btrfs_ioctl_vol_args *vol_args; 1784 int ret; 1785 1786 if (!S_ISDIR(file_inode(file)->i_mode)) 1787 return -ENOTDIR; 1788 1789 vol_args = memdup_user(arg, sizeof(*vol_args)); 1790 if (IS_ERR(vol_args)) 1791 return PTR_ERR(vol_args); 1792 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 1793 1794 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1795 vol_args->fd, subvol, 1796 NULL, false, NULL); 1797 1798 kfree(vol_args); 1799 return ret; 1800 } 1801 1802 static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 1803 void __user *arg, int subvol) 1804 { 1805 struct btrfs_ioctl_vol_args_v2 *vol_args; 1806 int ret; 1807 u64 transid = 0; 1808 u64 *ptr = NULL; 1809 bool readonly = false; 1810 struct btrfs_qgroup_inherit *inherit = NULL; 1811 1812 if (!S_ISDIR(file_inode(file)->i_mode)) 1813 return -ENOTDIR; 1814 1815 vol_args = memdup_user(arg, sizeof(*vol_args)); 1816 if (IS_ERR(vol_args)) 1817 return PTR_ERR(vol_args); 1818 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 1819 1820 if (vol_args->flags & 1821 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | 1822 BTRFS_SUBVOL_QGROUP_INHERIT)) { 1823 ret = -EOPNOTSUPP; 1824 goto free_args; 1825 } 1826 1827 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) 1828 ptr = &transid; 1829 if (vol_args->flags & BTRFS_SUBVOL_RDONLY) 1830 readonly = true; 1831 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { 1832 if (vol_args->size > PAGE_SIZE) { 1833 ret = -EINVAL; 1834 goto free_args; 1835 } 1836 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); 1837 if (IS_ERR(inherit)) { 1838 ret = PTR_ERR(inherit); 1839 goto free_args; 1840 } 1841 } 1842 1843 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, 1844 vol_args->fd, subvol, ptr, 1845 readonly, inherit); 1846 if (ret) 1847 goto free_inherit; 1848 1849 if (ptr && copy_to_user(arg + 1850 offsetof(struct btrfs_ioctl_vol_args_v2, 1851 transid), 1852 ptr, sizeof(*ptr))) 1853 ret = -EFAULT; 1854 1855 free_inherit: 1856 kfree(inherit); 1857 free_args: 1858 kfree(vol_args); 1859 return ret; 1860 } 1861 1862 static noinline int btrfs_ioctl_subvol_getflags(struct file *file, 1863 void __user *arg) 1864 { 1865 struct inode *inode = file_inode(file); 1866 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1867 struct btrfs_root *root = BTRFS_I(inode)->root; 1868 int ret = 0; 1869 u64 flags = 0; 1870 1871 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) 1872 return -EINVAL; 1873 1874 down_read(&fs_info->subvol_sem); 1875 if (btrfs_root_readonly(root)) 1876 flags |= BTRFS_SUBVOL_RDONLY; 1877 up_read(&fs_info->subvol_sem); 1878 1879 if (copy_to_user(arg, &flags, sizeof(flags))) 1880 ret = -EFAULT; 1881 1882 return ret; 1883 } 1884 1885 static noinline int btrfs_ioctl_subvol_setflags(struct file *file, 1886 void __user *arg) 1887 { 1888 struct inode *inode = file_inode(file); 1889 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1890 struct btrfs_root *root = BTRFS_I(inode)->root; 1891 struct btrfs_trans_handle *trans; 1892 u64 root_flags; 1893 u64 flags; 1894 int ret = 0; 1895 1896 if (!inode_owner_or_capable(inode)) 1897 return -EPERM; 1898 1899 ret = mnt_want_write_file(file); 1900 if (ret) 1901 goto out; 1902 1903 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { 1904 ret = -EINVAL; 1905 goto out_drop_write; 1906 } 1907 1908 if (copy_from_user(&flags, arg, sizeof(flags))) { 1909 ret = -EFAULT; 1910 goto out_drop_write; 1911 } 1912 1913 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) { 1914 ret = -EINVAL; 1915 goto out_drop_write; 1916 } 1917 1918 if (flags & ~BTRFS_SUBVOL_RDONLY) { 1919 ret = -EOPNOTSUPP; 1920 goto out_drop_write; 1921 } 1922 1923 down_write(&fs_info->subvol_sem); 1924 1925 /* nothing to do */ 1926 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) 1927 goto out_drop_sem; 1928 1929 root_flags = btrfs_root_flags(&root->root_item); 1930 if (flags & BTRFS_SUBVOL_RDONLY) { 1931 btrfs_set_root_flags(&root->root_item, 1932 root_flags | BTRFS_ROOT_SUBVOL_RDONLY); 1933 } else { 1934 /* 1935 * Block RO -> RW transition if this subvolume is involved in 1936 * send 1937 */ 1938 spin_lock(&root->root_item_lock); 1939 if (root->send_in_progress == 0) { 1940 btrfs_set_root_flags(&root->root_item, 1941 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 1942 spin_unlock(&root->root_item_lock); 1943 } else { 1944 spin_unlock(&root->root_item_lock); 1945 btrfs_warn(fs_info, 1946 "Attempt to set subvolume %llu read-write during send", 1947 root->root_key.objectid); 1948 ret = -EPERM; 1949 goto out_drop_sem; 1950 } 1951 } 1952 1953 trans = btrfs_start_transaction(root, 1); 1954 if (IS_ERR(trans)) { 1955 ret = PTR_ERR(trans); 1956 goto out_reset; 1957 } 1958 1959 ret = btrfs_update_root(trans, fs_info->tree_root, 1960 &root->root_key, &root->root_item); 1961 if (ret < 0) { 1962 btrfs_end_transaction(trans); 1963 goto out_reset; 1964 } 1965 1966 ret = btrfs_commit_transaction(trans); 1967 1968 out_reset: 1969 if (ret) 1970 btrfs_set_root_flags(&root->root_item, root_flags); 1971 out_drop_sem: 1972 up_write(&fs_info->subvol_sem); 1973 out_drop_write: 1974 mnt_drop_write_file(file); 1975 out: 1976 return ret; 1977 } 1978 1979 static noinline int key_in_sk(struct btrfs_key *key, 1980 struct btrfs_ioctl_search_key *sk) 1981 { 1982 struct btrfs_key test; 1983 int ret; 1984 1985 test.objectid = sk->min_objectid; 1986 test.type = sk->min_type; 1987 test.offset = sk->min_offset; 1988 1989 ret = btrfs_comp_cpu_keys(key, &test); 1990 if (ret < 0) 1991 return 0; 1992 1993 test.objectid = sk->max_objectid; 1994 test.type = sk->max_type; 1995 test.offset = sk->max_offset; 1996 1997 ret = btrfs_comp_cpu_keys(key, &test); 1998 if (ret > 0) 1999 return 0; 2000 return 1; 2001 } 2002 2003 static noinline int copy_to_sk(struct btrfs_path *path, 2004 struct btrfs_key *key, 2005 struct btrfs_ioctl_search_key *sk, 2006 size_t *buf_size, 2007 char __user *ubuf, 2008 unsigned long *sk_offset, 2009 int *num_found) 2010 { 2011 u64 found_transid; 2012 struct extent_buffer *leaf; 2013 struct btrfs_ioctl_search_header sh; 2014 struct btrfs_key test; 2015 unsigned long item_off; 2016 unsigned long item_len; 2017 int nritems; 2018 int i; 2019 int slot; 2020 int ret = 0; 2021 2022 leaf = path->nodes[0]; 2023 slot = path->slots[0]; 2024 nritems = btrfs_header_nritems(leaf); 2025 2026 if (btrfs_header_generation(leaf) > sk->max_transid) { 2027 i = nritems; 2028 goto advance_key; 2029 } 2030 found_transid = btrfs_header_generation(leaf); 2031 2032 for (i = slot; i < nritems; i++) { 2033 item_off = btrfs_item_ptr_offset(leaf, i); 2034 item_len = btrfs_item_size_nr(leaf, i); 2035 2036 btrfs_item_key_to_cpu(leaf, key, i); 2037 if (!key_in_sk(key, sk)) 2038 continue; 2039 2040 if (sizeof(sh) + item_len > *buf_size) { 2041 if (*num_found) { 2042 ret = 1; 2043 goto out; 2044 } 2045 2046 /* 2047 * return one empty item back for v1, which does not 2048 * handle -EOVERFLOW 2049 */ 2050 2051 *buf_size = sizeof(sh) + item_len; 2052 item_len = 0; 2053 ret = -EOVERFLOW; 2054 } 2055 2056 if (sizeof(sh) + item_len + *sk_offset > *buf_size) { 2057 ret = 1; 2058 goto out; 2059 } 2060 2061 sh.objectid = key->objectid; 2062 sh.offset = key->offset; 2063 sh.type = key->type; 2064 sh.len = item_len; 2065 sh.transid = found_transid; 2066 2067 /* copy search result header */ 2068 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) { 2069 ret = -EFAULT; 2070 goto out; 2071 } 2072 2073 *sk_offset += sizeof(sh); 2074 2075 if (item_len) { 2076 char __user *up = ubuf + *sk_offset; 2077 /* copy the item */ 2078 if (read_extent_buffer_to_user(leaf, up, 2079 item_off, item_len)) { 2080 ret = -EFAULT; 2081 goto out; 2082 } 2083 2084 *sk_offset += item_len; 2085 } 2086 (*num_found)++; 2087 2088 if (ret) /* -EOVERFLOW from above */ 2089 goto out; 2090 2091 if (*num_found >= sk->nr_items) { 2092 ret = 1; 2093 goto out; 2094 } 2095 } 2096 advance_key: 2097 ret = 0; 2098 test.objectid = sk->max_objectid; 2099 test.type = sk->max_type; 2100 test.offset = sk->max_offset; 2101 if (btrfs_comp_cpu_keys(key, &test) >= 0) 2102 ret = 1; 2103 else if (key->offset < (u64)-1) 2104 key->offset++; 2105 else if (key->type < (u8)-1) { 2106 key->offset = 0; 2107 key->type++; 2108 } else if (key->objectid < (u64)-1) { 2109 key->offset = 0; 2110 key->type = 0; 2111 key->objectid++; 2112 } else 2113 ret = 1; 2114 out: 2115 /* 2116 * 0: all items from this leaf copied, continue with next 2117 * 1: * more items can be copied, but unused buffer is too small 2118 * * all items were found 2119 * Either way, it will stops the loop which iterates to the next 2120 * leaf 2121 * -EOVERFLOW: item was to large for buffer 2122 * -EFAULT: could not copy extent buffer back to userspace 2123 */ 2124 return ret; 2125 } 2126 2127 static noinline int search_ioctl(struct inode *inode, 2128 struct btrfs_ioctl_search_key *sk, 2129 size_t *buf_size, 2130 char __user *ubuf) 2131 { 2132 struct btrfs_fs_info *info = btrfs_sb(inode->i_sb); 2133 struct btrfs_root *root; 2134 struct btrfs_key key; 2135 struct btrfs_path *path; 2136 int ret; 2137 int num_found = 0; 2138 unsigned long sk_offset = 0; 2139 2140 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) { 2141 *buf_size = sizeof(struct btrfs_ioctl_search_header); 2142 return -EOVERFLOW; 2143 } 2144 2145 path = btrfs_alloc_path(); 2146 if (!path) 2147 return -ENOMEM; 2148 2149 if (sk->tree_id == 0) { 2150 /* search the root of the inode that was passed */ 2151 root = BTRFS_I(inode)->root; 2152 } else { 2153 key.objectid = sk->tree_id; 2154 key.type = BTRFS_ROOT_ITEM_KEY; 2155 key.offset = (u64)-1; 2156 root = btrfs_read_fs_root_no_name(info, &key); 2157 if (IS_ERR(root)) { 2158 btrfs_free_path(path); 2159 return PTR_ERR(root); 2160 } 2161 } 2162 2163 key.objectid = sk->min_objectid; 2164 key.type = sk->min_type; 2165 key.offset = sk->min_offset; 2166 2167 while (1) { 2168 ret = btrfs_search_forward(root, &key, path, sk->min_transid); 2169 if (ret != 0) { 2170 if (ret > 0) 2171 ret = 0; 2172 goto err; 2173 } 2174 ret = copy_to_sk(path, &key, sk, buf_size, ubuf, 2175 &sk_offset, &num_found); 2176 btrfs_release_path(path); 2177 if (ret) 2178 break; 2179 2180 } 2181 if (ret > 0) 2182 ret = 0; 2183 err: 2184 sk->nr_items = num_found; 2185 btrfs_free_path(path); 2186 return ret; 2187 } 2188 2189 static noinline int btrfs_ioctl_tree_search(struct file *file, 2190 void __user *argp) 2191 { 2192 struct btrfs_ioctl_search_args __user *uargs; 2193 struct btrfs_ioctl_search_key sk; 2194 struct inode *inode; 2195 int ret; 2196 size_t buf_size; 2197 2198 if (!capable(CAP_SYS_ADMIN)) 2199 return -EPERM; 2200 2201 uargs = (struct btrfs_ioctl_search_args __user *)argp; 2202 2203 if (copy_from_user(&sk, &uargs->key, sizeof(sk))) 2204 return -EFAULT; 2205 2206 buf_size = sizeof(uargs->buf); 2207 2208 inode = file_inode(file); 2209 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf); 2210 2211 /* 2212 * In the origin implementation an overflow is handled by returning a 2213 * search header with a len of zero, so reset ret. 2214 */ 2215 if (ret == -EOVERFLOW) 2216 ret = 0; 2217 2218 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk))) 2219 ret = -EFAULT; 2220 return ret; 2221 } 2222 2223 static noinline int btrfs_ioctl_tree_search_v2(struct file *file, 2224 void __user *argp) 2225 { 2226 struct btrfs_ioctl_search_args_v2 __user *uarg; 2227 struct btrfs_ioctl_search_args_v2 args; 2228 struct inode *inode; 2229 int ret; 2230 size_t buf_size; 2231 const size_t buf_limit = SZ_16M; 2232 2233 if (!capable(CAP_SYS_ADMIN)) 2234 return -EPERM; 2235 2236 /* copy search header and buffer size */ 2237 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp; 2238 if (copy_from_user(&args, uarg, sizeof(args))) 2239 return -EFAULT; 2240 2241 buf_size = args.buf_size; 2242 2243 /* limit result size to 16MB */ 2244 if (buf_size > buf_limit) 2245 buf_size = buf_limit; 2246 2247 inode = file_inode(file); 2248 ret = search_ioctl(inode, &args.key, &buf_size, 2249 (char __user *)(&uarg->buf[0])); 2250 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key))) 2251 ret = -EFAULT; 2252 else if (ret == -EOVERFLOW && 2253 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size))) 2254 ret = -EFAULT; 2255 2256 return ret; 2257 } 2258 2259 /* 2260 * Search INODE_REFs to identify path name of 'dirid' directory 2261 * in a 'tree_id' tree. and sets path name to 'name'. 2262 */ 2263 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, 2264 u64 tree_id, u64 dirid, char *name) 2265 { 2266 struct btrfs_root *root; 2267 struct btrfs_key key; 2268 char *ptr; 2269 int ret = -1; 2270 int slot; 2271 int len; 2272 int total_len = 0; 2273 struct btrfs_inode_ref *iref; 2274 struct extent_buffer *l; 2275 struct btrfs_path *path; 2276 2277 if (dirid == BTRFS_FIRST_FREE_OBJECTID) { 2278 name[0]='\0'; 2279 return 0; 2280 } 2281 2282 path = btrfs_alloc_path(); 2283 if (!path) 2284 return -ENOMEM; 2285 2286 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1]; 2287 2288 key.objectid = tree_id; 2289 key.type = BTRFS_ROOT_ITEM_KEY; 2290 key.offset = (u64)-1; 2291 root = btrfs_read_fs_root_no_name(info, &key); 2292 if (IS_ERR(root)) { 2293 ret = PTR_ERR(root); 2294 goto out; 2295 } 2296 2297 key.objectid = dirid; 2298 key.type = BTRFS_INODE_REF_KEY; 2299 key.offset = (u64)-1; 2300 2301 while (1) { 2302 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2303 if (ret < 0) 2304 goto out; 2305 else if (ret > 0) { 2306 ret = btrfs_previous_item(root, path, dirid, 2307 BTRFS_INODE_REF_KEY); 2308 if (ret < 0) 2309 goto out; 2310 else if (ret > 0) { 2311 ret = -ENOENT; 2312 goto out; 2313 } 2314 } 2315 2316 l = path->nodes[0]; 2317 slot = path->slots[0]; 2318 btrfs_item_key_to_cpu(l, &key, slot); 2319 2320 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); 2321 len = btrfs_inode_ref_name_len(l, iref); 2322 ptr -= len + 1; 2323 total_len += len + 1; 2324 if (ptr < name) { 2325 ret = -ENAMETOOLONG; 2326 goto out; 2327 } 2328 2329 *(ptr + len) = '/'; 2330 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len); 2331 2332 if (key.offset == BTRFS_FIRST_FREE_OBJECTID) 2333 break; 2334 2335 btrfs_release_path(path); 2336 key.objectid = key.offset; 2337 key.offset = (u64)-1; 2338 dirid = key.objectid; 2339 } 2340 memmove(name, ptr, total_len); 2341 name[total_len] = '\0'; 2342 ret = 0; 2343 out: 2344 btrfs_free_path(path); 2345 return ret; 2346 } 2347 2348 static int btrfs_search_path_in_tree_user(struct inode *inode, 2349 struct btrfs_ioctl_ino_lookup_user_args *args) 2350 { 2351 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; 2352 struct super_block *sb = inode->i_sb; 2353 struct btrfs_key upper_limit = BTRFS_I(inode)->location; 2354 u64 treeid = BTRFS_I(inode)->root->root_key.objectid; 2355 u64 dirid = args->dirid; 2356 unsigned long item_off; 2357 unsigned long item_len; 2358 struct btrfs_inode_ref *iref; 2359 struct btrfs_root_ref *rref; 2360 struct btrfs_root *root; 2361 struct btrfs_path *path; 2362 struct btrfs_key key, key2; 2363 struct extent_buffer *leaf; 2364 struct inode *temp_inode; 2365 char *ptr; 2366 int slot; 2367 int len; 2368 int total_len = 0; 2369 int ret; 2370 2371 path = btrfs_alloc_path(); 2372 if (!path) 2373 return -ENOMEM; 2374 2375 /* 2376 * If the bottom subvolume does not exist directly under upper_limit, 2377 * construct the path in from the bottom up. 2378 */ 2379 if (dirid != upper_limit.objectid) { 2380 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1]; 2381 2382 key.objectid = treeid; 2383 key.type = BTRFS_ROOT_ITEM_KEY; 2384 key.offset = (u64)-1; 2385 root = btrfs_read_fs_root_no_name(fs_info, &key); 2386 if (IS_ERR(root)) { 2387 ret = PTR_ERR(root); 2388 goto out; 2389 } 2390 2391 key.objectid = dirid; 2392 key.type = BTRFS_INODE_REF_KEY; 2393 key.offset = (u64)-1; 2394 while (1) { 2395 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2396 if (ret < 0) { 2397 goto out; 2398 } else if (ret > 0) { 2399 ret = btrfs_previous_item(root, path, dirid, 2400 BTRFS_INODE_REF_KEY); 2401 if (ret < 0) { 2402 goto out; 2403 } else if (ret > 0) { 2404 ret = -ENOENT; 2405 goto out; 2406 } 2407 } 2408 2409 leaf = path->nodes[0]; 2410 slot = path->slots[0]; 2411 btrfs_item_key_to_cpu(leaf, &key, slot); 2412 2413 iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref); 2414 len = btrfs_inode_ref_name_len(leaf, iref); 2415 ptr -= len + 1; 2416 total_len += len + 1; 2417 if (ptr < args->path) { 2418 ret = -ENAMETOOLONG; 2419 goto out; 2420 } 2421 2422 *(ptr + len) = '/'; 2423 read_extent_buffer(leaf, ptr, 2424 (unsigned long)(iref + 1), len); 2425 2426 /* Check the read+exec permission of this directory */ 2427 ret = btrfs_previous_item(root, path, dirid, 2428 BTRFS_INODE_ITEM_KEY); 2429 if (ret < 0) { 2430 goto out; 2431 } else if (ret > 0) { 2432 ret = -ENOENT; 2433 goto out; 2434 } 2435 2436 leaf = path->nodes[0]; 2437 slot = path->slots[0]; 2438 btrfs_item_key_to_cpu(leaf, &key2, slot); 2439 if (key2.objectid != dirid) { 2440 ret = -ENOENT; 2441 goto out; 2442 } 2443 2444 temp_inode = btrfs_iget(sb, &key2, root, NULL); 2445 if (IS_ERR(temp_inode)) { 2446 ret = PTR_ERR(temp_inode); 2447 goto out; 2448 } 2449 ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC); 2450 iput(temp_inode); 2451 if (ret) { 2452 ret = -EACCES; 2453 goto out; 2454 } 2455 2456 if (key.offset == upper_limit.objectid) 2457 break; 2458 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) { 2459 ret = -EACCES; 2460 goto out; 2461 } 2462 2463 btrfs_release_path(path); 2464 key.objectid = key.offset; 2465 key.offset = (u64)-1; 2466 dirid = key.objectid; 2467 } 2468 2469 memmove(args->path, ptr, total_len); 2470 args->path[total_len] = '\0'; 2471 btrfs_release_path(path); 2472 } 2473 2474 /* Get the bottom subvolume's name from ROOT_REF */ 2475 root = fs_info->tree_root; 2476 key.objectid = treeid; 2477 key.type = BTRFS_ROOT_REF_KEY; 2478 key.offset = args->treeid; 2479 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2480 if (ret < 0) { 2481 goto out; 2482 } else if (ret > 0) { 2483 ret = -ENOENT; 2484 goto out; 2485 } 2486 2487 leaf = path->nodes[0]; 2488 slot = path->slots[0]; 2489 btrfs_item_key_to_cpu(leaf, &key, slot); 2490 2491 item_off = btrfs_item_ptr_offset(leaf, slot); 2492 item_len = btrfs_item_size_nr(leaf, slot); 2493 /* Check if dirid in ROOT_REF corresponds to passed dirid */ 2494 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref); 2495 if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) { 2496 ret = -EINVAL; 2497 goto out; 2498 } 2499 2500 /* Copy subvolume's name */ 2501 item_off += sizeof(struct btrfs_root_ref); 2502 item_len -= sizeof(struct btrfs_root_ref); 2503 read_extent_buffer(leaf, args->name, item_off, item_len); 2504 args->name[item_len] = 0; 2505 2506 out: 2507 btrfs_free_path(path); 2508 return ret; 2509 } 2510 2511 static noinline int btrfs_ioctl_ino_lookup(struct file *file, 2512 void __user *argp) 2513 { 2514 struct btrfs_ioctl_ino_lookup_args *args; 2515 struct inode *inode; 2516 int ret = 0; 2517 2518 args = memdup_user(argp, sizeof(*args)); 2519 if (IS_ERR(args)) 2520 return PTR_ERR(args); 2521 2522 inode = file_inode(file); 2523 2524 /* 2525 * Unprivileged query to obtain the containing subvolume root id. The 2526 * path is reset so it's consistent with btrfs_search_path_in_tree. 2527 */ 2528 if (args->treeid == 0) 2529 args->treeid = BTRFS_I(inode)->root->root_key.objectid; 2530 2531 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) { 2532 args->name[0] = 0; 2533 goto out; 2534 } 2535 2536 if (!capable(CAP_SYS_ADMIN)) { 2537 ret = -EPERM; 2538 goto out; 2539 } 2540 2541 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, 2542 args->treeid, args->objectid, 2543 args->name); 2544 2545 out: 2546 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 2547 ret = -EFAULT; 2548 2549 kfree(args); 2550 return ret; 2551 } 2552 2553 /* 2554 * Version of ino_lookup ioctl (unprivileged) 2555 * 2556 * The main differences from ino_lookup ioctl are: 2557 * 2558 * 1. Read + Exec permission will be checked using inode_permission() during 2559 * path construction. -EACCES will be returned in case of failure. 2560 * 2. Path construction will be stopped at the inode number which corresponds 2561 * to the fd with which this ioctl is called. If constructed path does not 2562 * exist under fd's inode, -EACCES will be returned. 2563 * 3. The name of bottom subvolume is also searched and filled. 2564 */ 2565 static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp) 2566 { 2567 struct btrfs_ioctl_ino_lookup_user_args *args; 2568 struct inode *inode; 2569 int ret; 2570 2571 args = memdup_user(argp, sizeof(*args)); 2572 if (IS_ERR(args)) 2573 return PTR_ERR(args); 2574 2575 inode = file_inode(file); 2576 2577 if (args->dirid == BTRFS_FIRST_FREE_OBJECTID && 2578 BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) { 2579 /* 2580 * The subvolume does not exist under fd with which this is 2581 * called 2582 */ 2583 kfree(args); 2584 return -EACCES; 2585 } 2586 2587 ret = btrfs_search_path_in_tree_user(inode, args); 2588 2589 if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) 2590 ret = -EFAULT; 2591 2592 kfree(args); 2593 return ret; 2594 } 2595 2596 /* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */ 2597 static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp) 2598 { 2599 struct btrfs_ioctl_get_subvol_info_args *subvol_info; 2600 struct btrfs_fs_info *fs_info; 2601 struct btrfs_root *root; 2602 struct btrfs_path *path; 2603 struct btrfs_key key; 2604 struct btrfs_root_item *root_item; 2605 struct btrfs_root_ref *rref; 2606 struct extent_buffer *leaf; 2607 unsigned long item_off; 2608 unsigned long item_len; 2609 struct inode *inode; 2610 int slot; 2611 int ret = 0; 2612 2613 path = btrfs_alloc_path(); 2614 if (!path) 2615 return -ENOMEM; 2616 2617 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL); 2618 if (!subvol_info) { 2619 btrfs_free_path(path); 2620 return -ENOMEM; 2621 } 2622 2623 inode = file_inode(file); 2624 fs_info = BTRFS_I(inode)->root->fs_info; 2625 2626 /* Get root_item of inode's subvolume */ 2627 key.objectid = BTRFS_I(inode)->root->root_key.objectid; 2628 key.type = BTRFS_ROOT_ITEM_KEY; 2629 key.offset = (u64)-1; 2630 root = btrfs_read_fs_root_no_name(fs_info, &key); 2631 if (IS_ERR(root)) { 2632 ret = PTR_ERR(root); 2633 goto out; 2634 } 2635 root_item = &root->root_item; 2636 2637 subvol_info->treeid = key.objectid; 2638 2639 subvol_info->generation = btrfs_root_generation(root_item); 2640 subvol_info->flags = btrfs_root_flags(root_item); 2641 2642 memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE); 2643 memcpy(subvol_info->parent_uuid, root_item->parent_uuid, 2644 BTRFS_UUID_SIZE); 2645 memcpy(subvol_info->received_uuid, root_item->received_uuid, 2646 BTRFS_UUID_SIZE); 2647 2648 subvol_info->ctransid = btrfs_root_ctransid(root_item); 2649 subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime); 2650 subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime); 2651 2652 subvol_info->otransid = btrfs_root_otransid(root_item); 2653 subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime); 2654 subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime); 2655 2656 subvol_info->stransid = btrfs_root_stransid(root_item); 2657 subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime); 2658 subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime); 2659 2660 subvol_info->rtransid = btrfs_root_rtransid(root_item); 2661 subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime); 2662 subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime); 2663 2664 if (key.objectid != BTRFS_FS_TREE_OBJECTID) { 2665 /* Search root tree for ROOT_BACKREF of this subvolume */ 2666 root = fs_info->tree_root; 2667 2668 key.type = BTRFS_ROOT_BACKREF_KEY; 2669 key.offset = 0; 2670 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2671 if (ret < 0) { 2672 goto out; 2673 } else if (path->slots[0] >= 2674 btrfs_header_nritems(path->nodes[0])) { 2675 ret = btrfs_next_leaf(root, path); 2676 if (ret < 0) { 2677 goto out; 2678 } else if (ret > 0) { 2679 ret = -EUCLEAN; 2680 goto out; 2681 } 2682 } 2683 2684 leaf = path->nodes[0]; 2685 slot = path->slots[0]; 2686 btrfs_item_key_to_cpu(leaf, &key, slot); 2687 if (key.objectid == subvol_info->treeid && 2688 key.type == BTRFS_ROOT_BACKREF_KEY) { 2689 subvol_info->parent_id = key.offset; 2690 2691 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref); 2692 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref); 2693 2694 item_off = btrfs_item_ptr_offset(leaf, slot) 2695 + sizeof(struct btrfs_root_ref); 2696 item_len = btrfs_item_size_nr(leaf, slot) 2697 - sizeof(struct btrfs_root_ref); 2698 read_extent_buffer(leaf, subvol_info->name, 2699 item_off, item_len); 2700 } else { 2701 ret = -ENOENT; 2702 goto out; 2703 } 2704 } 2705 2706 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info))) 2707 ret = -EFAULT; 2708 2709 out: 2710 btrfs_free_path(path); 2711 kzfree(subvol_info); 2712 return ret; 2713 } 2714 2715 /* 2716 * Return ROOT_REF information of the subvolume containing this inode 2717 * except the subvolume name. 2718 */ 2719 static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp) 2720 { 2721 struct btrfs_ioctl_get_subvol_rootref_args *rootrefs; 2722 struct btrfs_root_ref *rref; 2723 struct btrfs_root *root; 2724 struct btrfs_path *path; 2725 struct btrfs_key key; 2726 struct extent_buffer *leaf; 2727 struct inode *inode; 2728 u64 objectid; 2729 int slot; 2730 int ret; 2731 u8 found; 2732 2733 path = btrfs_alloc_path(); 2734 if (!path) 2735 return -ENOMEM; 2736 2737 rootrefs = memdup_user(argp, sizeof(*rootrefs)); 2738 if (IS_ERR(rootrefs)) { 2739 btrfs_free_path(path); 2740 return PTR_ERR(rootrefs); 2741 } 2742 2743 inode = file_inode(file); 2744 root = BTRFS_I(inode)->root->fs_info->tree_root; 2745 objectid = BTRFS_I(inode)->root->root_key.objectid; 2746 2747 key.objectid = objectid; 2748 key.type = BTRFS_ROOT_REF_KEY; 2749 key.offset = rootrefs->min_treeid; 2750 found = 0; 2751 2752 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2753 if (ret < 0) { 2754 goto out; 2755 } else if (path->slots[0] >= 2756 btrfs_header_nritems(path->nodes[0])) { 2757 ret = btrfs_next_leaf(root, path); 2758 if (ret < 0) { 2759 goto out; 2760 } else if (ret > 0) { 2761 ret = -EUCLEAN; 2762 goto out; 2763 } 2764 } 2765 while (1) { 2766 leaf = path->nodes[0]; 2767 slot = path->slots[0]; 2768 2769 btrfs_item_key_to_cpu(leaf, &key, slot); 2770 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) { 2771 ret = 0; 2772 goto out; 2773 } 2774 2775 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) { 2776 ret = -EOVERFLOW; 2777 goto out; 2778 } 2779 2780 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref); 2781 rootrefs->rootref[found].treeid = key.offset; 2782 rootrefs->rootref[found].dirid = 2783 btrfs_root_ref_dirid(leaf, rref); 2784 found++; 2785 2786 ret = btrfs_next_item(root, path); 2787 if (ret < 0) { 2788 goto out; 2789 } else if (ret > 0) { 2790 ret = -EUCLEAN; 2791 goto out; 2792 } 2793 } 2794 2795 out: 2796 if (!ret || ret == -EOVERFLOW) { 2797 rootrefs->num_items = found; 2798 /* update min_treeid for next search */ 2799 if (found) 2800 rootrefs->min_treeid = 2801 rootrefs->rootref[found - 1].treeid + 1; 2802 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs))) 2803 ret = -EFAULT; 2804 } 2805 2806 kfree(rootrefs); 2807 btrfs_free_path(path); 2808 2809 return ret; 2810 } 2811 2812 static noinline int btrfs_ioctl_snap_destroy(struct file *file, 2813 void __user *arg) 2814 { 2815 struct dentry *parent = file->f_path.dentry; 2816 struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb); 2817 struct dentry *dentry; 2818 struct inode *dir = d_inode(parent); 2819 struct inode *inode; 2820 struct btrfs_root *root = BTRFS_I(dir)->root; 2821 struct btrfs_root *dest = NULL; 2822 struct btrfs_ioctl_vol_args *vol_args; 2823 int namelen; 2824 int err = 0; 2825 2826 if (!S_ISDIR(dir->i_mode)) 2827 return -ENOTDIR; 2828 2829 vol_args = memdup_user(arg, sizeof(*vol_args)); 2830 if (IS_ERR(vol_args)) 2831 return PTR_ERR(vol_args); 2832 2833 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 2834 namelen = strlen(vol_args->name); 2835 if (strchr(vol_args->name, '/') || 2836 strncmp(vol_args->name, "..", namelen) == 0) { 2837 err = -EINVAL; 2838 goto out; 2839 } 2840 2841 err = mnt_want_write_file(file); 2842 if (err) 2843 goto out; 2844 2845 2846 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT); 2847 if (err == -EINTR) 2848 goto out_drop_write; 2849 dentry = lookup_one_len(vol_args->name, parent, namelen); 2850 if (IS_ERR(dentry)) { 2851 err = PTR_ERR(dentry); 2852 goto out_unlock_dir; 2853 } 2854 2855 if (d_really_is_negative(dentry)) { 2856 err = -ENOENT; 2857 goto out_dput; 2858 } 2859 2860 inode = d_inode(dentry); 2861 dest = BTRFS_I(inode)->root; 2862 if (!capable(CAP_SYS_ADMIN)) { 2863 /* 2864 * Regular user. Only allow this with a special mount 2865 * option, when the user has write+exec access to the 2866 * subvol root, and when rmdir(2) would have been 2867 * allowed. 2868 * 2869 * Note that this is _not_ check that the subvol is 2870 * empty or doesn't contain data that we wouldn't 2871 * otherwise be able to delete. 2872 * 2873 * Users who want to delete empty subvols should try 2874 * rmdir(2). 2875 */ 2876 err = -EPERM; 2877 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED)) 2878 goto out_dput; 2879 2880 /* 2881 * Do not allow deletion if the parent dir is the same 2882 * as the dir to be deleted. That means the ioctl 2883 * must be called on the dentry referencing the root 2884 * of the subvol, not a random directory contained 2885 * within it. 2886 */ 2887 err = -EINVAL; 2888 if (root == dest) 2889 goto out_dput; 2890 2891 err = inode_permission(inode, MAY_WRITE | MAY_EXEC); 2892 if (err) 2893 goto out_dput; 2894 } 2895 2896 /* check if subvolume may be deleted by a user */ 2897 err = btrfs_may_delete(dir, dentry, 1); 2898 if (err) 2899 goto out_dput; 2900 2901 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { 2902 err = -EINVAL; 2903 goto out_dput; 2904 } 2905 2906 inode_lock(inode); 2907 err = btrfs_delete_subvolume(dir, dentry); 2908 inode_unlock(inode); 2909 if (!err) 2910 d_delete(dentry); 2911 2912 out_dput: 2913 dput(dentry); 2914 out_unlock_dir: 2915 inode_unlock(dir); 2916 out_drop_write: 2917 mnt_drop_write_file(file); 2918 out: 2919 kfree(vol_args); 2920 return err; 2921 } 2922 2923 static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 2924 { 2925 struct inode *inode = file_inode(file); 2926 struct btrfs_root *root = BTRFS_I(inode)->root; 2927 struct btrfs_ioctl_defrag_range_args *range; 2928 int ret; 2929 2930 ret = mnt_want_write_file(file); 2931 if (ret) 2932 return ret; 2933 2934 if (btrfs_root_readonly(root)) { 2935 ret = -EROFS; 2936 goto out; 2937 } 2938 2939 switch (inode->i_mode & S_IFMT) { 2940 case S_IFDIR: 2941 if (!capable(CAP_SYS_ADMIN)) { 2942 ret = -EPERM; 2943 goto out; 2944 } 2945 ret = btrfs_defrag_root(root); 2946 break; 2947 case S_IFREG: 2948 /* 2949 * Note that this does not check the file descriptor for write 2950 * access. This prevents defragmenting executables that are 2951 * running and allows defrag on files open in read-only mode. 2952 */ 2953 if (!capable(CAP_SYS_ADMIN) && 2954 inode_permission(inode, MAY_WRITE)) { 2955 ret = -EPERM; 2956 goto out; 2957 } 2958 2959 range = kzalloc(sizeof(*range), GFP_KERNEL); 2960 if (!range) { 2961 ret = -ENOMEM; 2962 goto out; 2963 } 2964 2965 if (argp) { 2966 if (copy_from_user(range, argp, 2967 sizeof(*range))) { 2968 ret = -EFAULT; 2969 kfree(range); 2970 goto out; 2971 } 2972 /* compression requires us to start the IO */ 2973 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { 2974 range->flags |= BTRFS_DEFRAG_RANGE_START_IO; 2975 range->extent_thresh = (u32)-1; 2976 } 2977 } else { 2978 /* the rest are all set to zero by kzalloc */ 2979 range->len = (u64)-1; 2980 } 2981 ret = btrfs_defrag_file(file_inode(file), file, 2982 range, BTRFS_OLDEST_GENERATION, 0); 2983 if (ret > 0) 2984 ret = 0; 2985 kfree(range); 2986 break; 2987 default: 2988 ret = -EINVAL; 2989 } 2990 out: 2991 mnt_drop_write_file(file); 2992 return ret; 2993 } 2994 2995 static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg) 2996 { 2997 struct btrfs_ioctl_vol_args *vol_args; 2998 int ret; 2999 3000 if (!capable(CAP_SYS_ADMIN)) 3001 return -EPERM; 3002 3003 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) 3004 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 3005 3006 vol_args = memdup_user(arg, sizeof(*vol_args)); 3007 if (IS_ERR(vol_args)) { 3008 ret = PTR_ERR(vol_args); 3009 goto out; 3010 } 3011 3012 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 3013 ret = btrfs_init_new_device(fs_info, vol_args->name); 3014 3015 if (!ret) 3016 btrfs_info(fs_info, "disk added %s", vol_args->name); 3017 3018 kfree(vol_args); 3019 out: 3020 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 3021 return ret; 3022 } 3023 3024 static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg) 3025 { 3026 struct inode *inode = file_inode(file); 3027 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3028 struct btrfs_ioctl_vol_args_v2 *vol_args; 3029 int ret; 3030 3031 if (!capable(CAP_SYS_ADMIN)) 3032 return -EPERM; 3033 3034 ret = mnt_want_write_file(file); 3035 if (ret) 3036 return ret; 3037 3038 vol_args = memdup_user(arg, sizeof(*vol_args)); 3039 if (IS_ERR(vol_args)) { 3040 ret = PTR_ERR(vol_args); 3041 goto err_drop; 3042 } 3043 3044 /* Check for compatibility reject unknown flags */ 3045 if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED) { 3046 ret = -EOPNOTSUPP; 3047 goto out; 3048 } 3049 3050 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { 3051 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 3052 goto out; 3053 } 3054 3055 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) { 3056 ret = btrfs_rm_device(fs_info, NULL, vol_args->devid); 3057 } else { 3058 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; 3059 ret = btrfs_rm_device(fs_info, vol_args->name, 0); 3060 } 3061 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 3062 3063 if (!ret) { 3064 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) 3065 btrfs_info(fs_info, "device deleted: id %llu", 3066 vol_args->devid); 3067 else 3068 btrfs_info(fs_info, "device deleted: %s", 3069 vol_args->name); 3070 } 3071 out: 3072 kfree(vol_args); 3073 err_drop: 3074 mnt_drop_write_file(file); 3075 return ret; 3076 } 3077 3078 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) 3079 { 3080 struct inode *inode = file_inode(file); 3081 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3082 struct btrfs_ioctl_vol_args *vol_args; 3083 int ret; 3084 3085 if (!capable(CAP_SYS_ADMIN)) 3086 return -EPERM; 3087 3088 ret = mnt_want_write_file(file); 3089 if (ret) 3090 return ret; 3091 3092 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { 3093 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 3094 goto out_drop_write; 3095 } 3096 3097 vol_args = memdup_user(arg, sizeof(*vol_args)); 3098 if (IS_ERR(vol_args)) { 3099 ret = PTR_ERR(vol_args); 3100 goto out; 3101 } 3102 3103 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; 3104 ret = btrfs_rm_device(fs_info, vol_args->name, 0); 3105 3106 if (!ret) 3107 btrfs_info(fs_info, "disk deleted %s", vol_args->name); 3108 kfree(vol_args); 3109 out: 3110 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 3111 out_drop_write: 3112 mnt_drop_write_file(file); 3113 3114 return ret; 3115 } 3116 3117 static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info, 3118 void __user *arg) 3119 { 3120 struct btrfs_ioctl_fs_info_args *fi_args; 3121 struct btrfs_device *device; 3122 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 3123 int ret = 0; 3124 3125 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); 3126 if (!fi_args) 3127 return -ENOMEM; 3128 3129 rcu_read_lock(); 3130 fi_args->num_devices = fs_devices->num_devices; 3131 3132 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) { 3133 if (device->devid > fi_args->max_id) 3134 fi_args->max_id = device->devid; 3135 } 3136 rcu_read_unlock(); 3137 3138 memcpy(&fi_args->fsid, fs_info->fsid, sizeof(fi_args->fsid)); 3139 fi_args->nodesize = fs_info->nodesize; 3140 fi_args->sectorsize = fs_info->sectorsize; 3141 fi_args->clone_alignment = fs_info->sectorsize; 3142 3143 if (copy_to_user(arg, fi_args, sizeof(*fi_args))) 3144 ret = -EFAULT; 3145 3146 kfree(fi_args); 3147 return ret; 3148 } 3149 3150 static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info, 3151 void __user *arg) 3152 { 3153 struct btrfs_ioctl_dev_info_args *di_args; 3154 struct btrfs_device *dev; 3155 int ret = 0; 3156 char *s_uuid = NULL; 3157 3158 di_args = memdup_user(arg, sizeof(*di_args)); 3159 if (IS_ERR(di_args)) 3160 return PTR_ERR(di_args); 3161 3162 if (!btrfs_is_empty_uuid(di_args->uuid)) 3163 s_uuid = di_args->uuid; 3164 3165 rcu_read_lock(); 3166 dev = btrfs_find_device(fs_info, di_args->devid, s_uuid, NULL); 3167 3168 if (!dev) { 3169 ret = -ENODEV; 3170 goto out; 3171 } 3172 3173 di_args->devid = dev->devid; 3174 di_args->bytes_used = btrfs_device_get_bytes_used(dev); 3175 di_args->total_bytes = btrfs_device_get_total_bytes(dev); 3176 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); 3177 if (dev->name) { 3178 strncpy(di_args->path, rcu_str_deref(dev->name), 3179 sizeof(di_args->path) - 1); 3180 di_args->path[sizeof(di_args->path) - 1] = 0; 3181 } else { 3182 di_args->path[0] = '\0'; 3183 } 3184 3185 out: 3186 rcu_read_unlock(); 3187 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) 3188 ret = -EFAULT; 3189 3190 kfree(di_args); 3191 return ret; 3192 } 3193 3194 static struct page *extent_same_get_page(struct inode *inode, pgoff_t index) 3195 { 3196 struct page *page; 3197 3198 page = grab_cache_page(inode->i_mapping, index); 3199 if (!page) 3200 return ERR_PTR(-ENOMEM); 3201 3202 if (!PageUptodate(page)) { 3203 int ret; 3204 3205 ret = btrfs_readpage(NULL, page); 3206 if (ret) 3207 return ERR_PTR(ret); 3208 lock_page(page); 3209 if (!PageUptodate(page)) { 3210 unlock_page(page); 3211 put_page(page); 3212 return ERR_PTR(-EIO); 3213 } 3214 if (page->mapping != inode->i_mapping) { 3215 unlock_page(page); 3216 put_page(page); 3217 return ERR_PTR(-EAGAIN); 3218 } 3219 } 3220 3221 return page; 3222 } 3223 3224 static int gather_extent_pages(struct inode *inode, struct page **pages, 3225 int num_pages, u64 off) 3226 { 3227 int i; 3228 pgoff_t index = off >> PAGE_SHIFT; 3229 3230 for (i = 0; i < num_pages; i++) { 3231 again: 3232 pages[i] = extent_same_get_page(inode, index + i); 3233 if (IS_ERR(pages[i])) { 3234 int err = PTR_ERR(pages[i]); 3235 3236 if (err == -EAGAIN) 3237 goto again; 3238 pages[i] = NULL; 3239 return err; 3240 } 3241 } 3242 return 0; 3243 } 3244 3245 static int lock_extent_range(struct inode *inode, u64 off, u64 len, 3246 bool retry_range_locking) 3247 { 3248 /* 3249 * Do any pending delalloc/csum calculations on inode, one way or 3250 * another, and lock file content. 3251 * The locking order is: 3252 * 3253 * 1) pages 3254 * 2) range in the inode's io tree 3255 */ 3256 while (1) { 3257 struct btrfs_ordered_extent *ordered; 3258 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); 3259 ordered = btrfs_lookup_first_ordered_extent(inode, 3260 off + len - 1); 3261 if ((!ordered || 3262 ordered->file_offset + ordered->len <= off || 3263 ordered->file_offset >= off + len) && 3264 !test_range_bit(&BTRFS_I(inode)->io_tree, off, 3265 off + len - 1, EXTENT_DELALLOC, 0, NULL)) { 3266 if (ordered) 3267 btrfs_put_ordered_extent(ordered); 3268 break; 3269 } 3270 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); 3271 if (ordered) 3272 btrfs_put_ordered_extent(ordered); 3273 if (!retry_range_locking) 3274 return -EAGAIN; 3275 btrfs_wait_ordered_range(inode, off, len); 3276 } 3277 return 0; 3278 } 3279 3280 static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2) 3281 { 3282 inode_unlock(inode1); 3283 inode_unlock(inode2); 3284 } 3285 3286 static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2) 3287 { 3288 if (inode1 < inode2) 3289 swap(inode1, inode2); 3290 3291 inode_lock_nested(inode1, I_MUTEX_PARENT); 3292 inode_lock_nested(inode2, I_MUTEX_CHILD); 3293 } 3294 3295 static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1, 3296 struct inode *inode2, u64 loff2, u64 len) 3297 { 3298 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1); 3299 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1); 3300 } 3301 3302 static int btrfs_double_extent_lock(struct inode *inode1, u64 loff1, 3303 struct inode *inode2, u64 loff2, u64 len, 3304 bool retry_range_locking) 3305 { 3306 int ret; 3307 3308 if (inode1 < inode2) { 3309 swap(inode1, inode2); 3310 swap(loff1, loff2); 3311 } 3312 ret = lock_extent_range(inode1, loff1, len, retry_range_locking); 3313 if (ret) 3314 return ret; 3315 ret = lock_extent_range(inode2, loff2, len, retry_range_locking); 3316 if (ret) 3317 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, 3318 loff1 + len - 1); 3319 return ret; 3320 } 3321 3322 struct cmp_pages { 3323 int num_pages; 3324 struct page **src_pages; 3325 struct page **dst_pages; 3326 }; 3327 3328 static void btrfs_cmp_data_free(struct cmp_pages *cmp) 3329 { 3330 int i; 3331 struct page *pg; 3332 3333 for (i = 0; i < cmp->num_pages; i++) { 3334 pg = cmp->src_pages[i]; 3335 if (pg) { 3336 unlock_page(pg); 3337 put_page(pg); 3338 cmp->src_pages[i] = NULL; 3339 } 3340 pg = cmp->dst_pages[i]; 3341 if (pg) { 3342 unlock_page(pg); 3343 put_page(pg); 3344 cmp->dst_pages[i] = NULL; 3345 } 3346 } 3347 } 3348 3349 static int btrfs_cmp_data_prepare(struct inode *src, u64 loff, 3350 struct inode *dst, u64 dst_loff, 3351 u64 len, struct cmp_pages *cmp) 3352 { 3353 int ret; 3354 int num_pages = PAGE_ALIGN(len) >> PAGE_SHIFT; 3355 3356 cmp->num_pages = num_pages; 3357 3358 ret = gather_extent_pages(src, cmp->src_pages, num_pages, loff); 3359 if (ret) 3360 goto out; 3361 3362 ret = gather_extent_pages(dst, cmp->dst_pages, num_pages, dst_loff); 3363 3364 out: 3365 if (ret) 3366 btrfs_cmp_data_free(cmp); 3367 return ret; 3368 } 3369 3370 static int btrfs_cmp_data(u64 len, struct cmp_pages *cmp) 3371 { 3372 int ret = 0; 3373 int i; 3374 struct page *src_page, *dst_page; 3375 unsigned int cmp_len = PAGE_SIZE; 3376 void *addr, *dst_addr; 3377 3378 i = 0; 3379 while (len) { 3380 if (len < PAGE_SIZE) 3381 cmp_len = len; 3382 3383 BUG_ON(i >= cmp->num_pages); 3384 3385 src_page = cmp->src_pages[i]; 3386 dst_page = cmp->dst_pages[i]; 3387 ASSERT(PageLocked(src_page)); 3388 ASSERT(PageLocked(dst_page)); 3389 3390 addr = kmap_atomic(src_page); 3391 dst_addr = kmap_atomic(dst_page); 3392 3393 flush_dcache_page(src_page); 3394 flush_dcache_page(dst_page); 3395 3396 if (memcmp(addr, dst_addr, cmp_len)) 3397 ret = -EBADE; 3398 3399 kunmap_atomic(addr); 3400 kunmap_atomic(dst_addr); 3401 3402 if (ret) 3403 break; 3404 3405 len -= cmp_len; 3406 i++; 3407 } 3408 3409 return ret; 3410 } 3411 3412 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen, 3413 u64 olen) 3414 { 3415 u64 len = *plen; 3416 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize; 3417 3418 if (off + olen > inode->i_size || off + olen < off) 3419 return -EINVAL; 3420 3421 /* if we extend to eof, continue to block boundary */ 3422 if (off + len == inode->i_size) 3423 *plen = len = ALIGN(inode->i_size, bs) - off; 3424 3425 /* Check that we are block aligned - btrfs_clone() requires this */ 3426 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs)) 3427 return -EINVAL; 3428 3429 return 0; 3430 } 3431 3432 static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 olen, 3433 struct inode *dst, u64 dst_loff, 3434 struct cmp_pages *cmp) 3435 { 3436 int ret; 3437 u64 len = olen; 3438 bool same_inode = (src == dst); 3439 u64 same_lock_start = 0; 3440 u64 same_lock_len = 0; 3441 3442 ret = extent_same_check_offsets(src, loff, &len, olen); 3443 if (ret) 3444 return ret; 3445 3446 ret = extent_same_check_offsets(dst, dst_loff, &len, olen); 3447 if (ret) 3448 return ret; 3449 3450 if (same_inode) { 3451 /* 3452 * Single inode case wants the same checks, except we 3453 * don't want our length pushed out past i_size as 3454 * comparing that data range makes no sense. 3455 * 3456 * extent_same_check_offsets() will do this for an 3457 * unaligned length at i_size, so catch it here and 3458 * reject the request. 3459 * 3460 * This effectively means we require aligned extents 3461 * for the single-inode case, whereas the other cases 3462 * allow an unaligned length so long as it ends at 3463 * i_size. 3464 */ 3465 if (len != olen) 3466 return -EINVAL; 3467 3468 /* Check for overlapping ranges */ 3469 if (dst_loff + len > loff && dst_loff < loff + len) 3470 return -EINVAL; 3471 3472 same_lock_start = min_t(u64, loff, dst_loff); 3473 same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start; 3474 } else { 3475 /* 3476 * If the source and destination inodes are different, the 3477 * source's range end offset matches the source's i_size, that 3478 * i_size is not a multiple of the sector size, and the 3479 * destination range does not go past the destination's i_size, 3480 * we must round down the length to the nearest sector size 3481 * multiple. If we don't do this adjustment we end replacing 3482 * with zeroes the bytes in the range that starts at the 3483 * deduplication range's end offset and ends at the next sector 3484 * size multiple. 3485 */ 3486 if (loff + olen == i_size_read(src) && 3487 dst_loff + len < i_size_read(dst)) { 3488 const u64 sz = BTRFS_I(src)->root->fs_info->sectorsize; 3489 3490 len = round_down(i_size_read(src), sz) - loff; 3491 if (len == 0) 3492 return 0; 3493 olen = len; 3494 } 3495 } 3496 3497 again: 3498 ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, cmp); 3499 if (ret) 3500 return ret; 3501 3502 if (same_inode) 3503 ret = lock_extent_range(src, same_lock_start, same_lock_len, 3504 false); 3505 else 3506 ret = btrfs_double_extent_lock(src, loff, dst, dst_loff, len, 3507 false); 3508 /* 3509 * If one of the inodes has dirty pages in the respective range or 3510 * ordered extents, we need to flush dellaloc and wait for all ordered 3511 * extents in the range. We must unlock the pages and the ranges in the 3512 * io trees to avoid deadlocks when flushing delalloc (requires locking 3513 * pages) and when waiting for ordered extents to complete (they require 3514 * range locking). 3515 */ 3516 if (ret == -EAGAIN) { 3517 /* 3518 * Ranges in the io trees already unlocked. Now unlock all 3519 * pages before waiting for all IO to complete. 3520 */ 3521 btrfs_cmp_data_free(cmp); 3522 if (same_inode) { 3523 btrfs_wait_ordered_range(src, same_lock_start, 3524 same_lock_len); 3525 } else { 3526 btrfs_wait_ordered_range(src, loff, len); 3527 btrfs_wait_ordered_range(dst, dst_loff, len); 3528 } 3529 goto again; 3530 } 3531 ASSERT(ret == 0); 3532 if (WARN_ON(ret)) { 3533 /* ranges in the io trees already unlocked */ 3534 btrfs_cmp_data_free(cmp); 3535 return ret; 3536 } 3537 3538 /* pass original length for comparison so we stay within i_size */ 3539 ret = btrfs_cmp_data(olen, cmp); 3540 if (ret == 0) 3541 ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1); 3542 3543 if (same_inode) 3544 unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start, 3545 same_lock_start + same_lock_len - 1); 3546 else 3547 btrfs_double_extent_unlock(src, loff, dst, dst_loff, len); 3548 3549 btrfs_cmp_data_free(cmp); 3550 3551 return ret; 3552 } 3553 3554 #define BTRFS_MAX_DEDUPE_LEN SZ_16M 3555 3556 static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen, 3557 struct inode *dst, u64 dst_loff) 3558 { 3559 int ret; 3560 struct cmp_pages cmp; 3561 int num_pages = PAGE_ALIGN(BTRFS_MAX_DEDUPE_LEN) >> PAGE_SHIFT; 3562 bool same_inode = (src == dst); 3563 u64 i, tail_len, chunk_count; 3564 3565 if (olen == 0) 3566 return 0; 3567 3568 if (same_inode) 3569 inode_lock(src); 3570 else 3571 btrfs_double_inode_lock(src, dst); 3572 3573 /* don't make the dst file partly checksummed */ 3574 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 3575 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) { 3576 ret = -EINVAL; 3577 goto out_unlock; 3578 } 3579 3580 tail_len = olen % BTRFS_MAX_DEDUPE_LEN; 3581 chunk_count = div_u64(olen, BTRFS_MAX_DEDUPE_LEN); 3582 if (chunk_count == 0) 3583 num_pages = PAGE_ALIGN(tail_len) >> PAGE_SHIFT; 3584 3585 /* 3586 * If deduping ranges in the same inode, locking rules make it 3587 * mandatory to always lock pages in ascending order to avoid deadlocks 3588 * with concurrent tasks (such as starting writeback/delalloc). 3589 */ 3590 if (same_inode && dst_loff < loff) 3591 swap(loff, dst_loff); 3592 3593 /* 3594 * We must gather up all the pages before we initiate our extent 3595 * locking. We use an array for the page pointers. Size of the array is 3596 * bounded by len, which is in turn bounded by BTRFS_MAX_DEDUPE_LEN. 3597 */ 3598 cmp.src_pages = kvmalloc_array(num_pages, sizeof(struct page *), 3599 GFP_KERNEL | __GFP_ZERO); 3600 cmp.dst_pages = kvmalloc_array(num_pages, sizeof(struct page *), 3601 GFP_KERNEL | __GFP_ZERO); 3602 if (!cmp.src_pages || !cmp.dst_pages) { 3603 ret = -ENOMEM; 3604 goto out_free; 3605 } 3606 3607 for (i = 0; i < chunk_count; i++) { 3608 ret = btrfs_extent_same_range(src, loff, BTRFS_MAX_DEDUPE_LEN, 3609 dst, dst_loff, &cmp); 3610 if (ret) 3611 goto out_free; 3612 3613 loff += BTRFS_MAX_DEDUPE_LEN; 3614 dst_loff += BTRFS_MAX_DEDUPE_LEN; 3615 } 3616 3617 if (tail_len > 0) 3618 ret = btrfs_extent_same_range(src, loff, tail_len, dst, 3619 dst_loff, &cmp); 3620 3621 out_free: 3622 kvfree(cmp.src_pages); 3623 kvfree(cmp.dst_pages); 3624 3625 out_unlock: 3626 if (same_inode) 3627 inode_unlock(src); 3628 else 3629 btrfs_double_inode_unlock(src, dst); 3630 3631 return ret; 3632 } 3633 3634 static int clone_finish_inode_update(struct btrfs_trans_handle *trans, 3635 struct inode *inode, 3636 u64 endoff, 3637 const u64 destoff, 3638 const u64 olen, 3639 int no_time_update) 3640 { 3641 struct btrfs_root *root = BTRFS_I(inode)->root; 3642 int ret; 3643 3644 inode_inc_iversion(inode); 3645 if (!no_time_update) 3646 inode->i_mtime = inode->i_ctime = current_time(inode); 3647 /* 3648 * We round up to the block size at eof when determining which 3649 * extents to clone above, but shouldn't round up the file size. 3650 */ 3651 if (endoff > destoff + olen) 3652 endoff = destoff + olen; 3653 if (endoff > inode->i_size) 3654 btrfs_i_size_write(BTRFS_I(inode), endoff); 3655 3656 ret = btrfs_update_inode(trans, root, inode); 3657 if (ret) { 3658 btrfs_abort_transaction(trans, ret); 3659 btrfs_end_transaction(trans); 3660 goto out; 3661 } 3662 ret = btrfs_end_transaction(trans); 3663 out: 3664 return ret; 3665 } 3666 3667 static void clone_update_extent_map(struct btrfs_inode *inode, 3668 const struct btrfs_trans_handle *trans, 3669 const struct btrfs_path *path, 3670 const u64 hole_offset, 3671 const u64 hole_len) 3672 { 3673 struct extent_map_tree *em_tree = &inode->extent_tree; 3674 struct extent_map *em; 3675 int ret; 3676 3677 em = alloc_extent_map(); 3678 if (!em) { 3679 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags); 3680 return; 3681 } 3682 3683 if (path) { 3684 struct btrfs_file_extent_item *fi; 3685 3686 fi = btrfs_item_ptr(path->nodes[0], path->slots[0], 3687 struct btrfs_file_extent_item); 3688 btrfs_extent_item_to_extent_map(inode, path, fi, false, em); 3689 em->generation = -1; 3690 if (btrfs_file_extent_type(path->nodes[0], fi) == 3691 BTRFS_FILE_EXTENT_INLINE) 3692 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3693 &inode->runtime_flags); 3694 } else { 3695 em->start = hole_offset; 3696 em->len = hole_len; 3697 em->ram_bytes = em->len; 3698 em->orig_start = hole_offset; 3699 em->block_start = EXTENT_MAP_HOLE; 3700 em->block_len = 0; 3701 em->orig_block_len = 0; 3702 em->compress_type = BTRFS_COMPRESS_NONE; 3703 em->generation = trans->transid; 3704 } 3705 3706 while (1) { 3707 write_lock(&em_tree->lock); 3708 ret = add_extent_mapping(em_tree, em, 1); 3709 write_unlock(&em_tree->lock); 3710 if (ret != -EEXIST) { 3711 free_extent_map(em); 3712 break; 3713 } 3714 btrfs_drop_extent_cache(inode, em->start, 3715 em->start + em->len - 1, 0); 3716 } 3717 3718 if (ret) 3719 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags); 3720 } 3721 3722 /* 3723 * Make sure we do not end up inserting an inline extent into a file that has 3724 * already other (non-inline) extents. If a file has an inline extent it can 3725 * not have any other extents and the (single) inline extent must start at the 3726 * file offset 0. Failing to respect these rules will lead to file corruption, 3727 * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc 3728 * 3729 * We can have extents that have been already written to disk or we can have 3730 * dirty ranges still in delalloc, in which case the extent maps and items are 3731 * created only when we run delalloc, and the delalloc ranges might fall outside 3732 * the range we are currently locking in the inode's io tree. So we check the 3733 * inode's i_size because of that (i_size updates are done while holding the 3734 * i_mutex, which we are holding here). 3735 * We also check to see if the inode has a size not greater than "datal" but has 3736 * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are 3737 * protected against such concurrent fallocate calls by the i_mutex). 3738 * 3739 * If the file has no extents but a size greater than datal, do not allow the 3740 * copy because we would need turn the inline extent into a non-inline one (even 3741 * with NO_HOLES enabled). If we find our destination inode only has one inline 3742 * extent, just overwrite it with the source inline extent if its size is less 3743 * than the source extent's size, or we could copy the source inline extent's 3744 * data into the destination inode's inline extent if the later is greater then 3745 * the former. 3746 */ 3747 static int clone_copy_inline_extent(struct inode *dst, 3748 struct btrfs_trans_handle *trans, 3749 struct btrfs_path *path, 3750 struct btrfs_key *new_key, 3751 const u64 drop_start, 3752 const u64 datal, 3753 const u64 skip, 3754 const u64 size, 3755 char *inline_data) 3756 { 3757 struct btrfs_fs_info *fs_info = btrfs_sb(dst->i_sb); 3758 struct btrfs_root *root = BTRFS_I(dst)->root; 3759 const u64 aligned_end = ALIGN(new_key->offset + datal, 3760 fs_info->sectorsize); 3761 int ret; 3762 struct btrfs_key key; 3763 3764 if (new_key->offset > 0) 3765 return -EOPNOTSUPP; 3766 3767 key.objectid = btrfs_ino(BTRFS_I(dst)); 3768 key.type = BTRFS_EXTENT_DATA_KEY; 3769 key.offset = 0; 3770 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3771 if (ret < 0) { 3772 return ret; 3773 } else if (ret > 0) { 3774 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { 3775 ret = btrfs_next_leaf(root, path); 3776 if (ret < 0) 3777 return ret; 3778 else if (ret > 0) 3779 goto copy_inline_extent; 3780 } 3781 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 3782 if (key.objectid == btrfs_ino(BTRFS_I(dst)) && 3783 key.type == BTRFS_EXTENT_DATA_KEY) { 3784 ASSERT(key.offset > 0); 3785 return -EOPNOTSUPP; 3786 } 3787 } else if (i_size_read(dst) <= datal) { 3788 struct btrfs_file_extent_item *ei; 3789 u64 ext_len; 3790 3791 /* 3792 * If the file size is <= datal, make sure there are no other 3793 * extents following (can happen do to an fallocate call with 3794 * the flag FALLOC_FL_KEEP_SIZE). 3795 */ 3796 ei = btrfs_item_ptr(path->nodes[0], path->slots[0], 3797 struct btrfs_file_extent_item); 3798 /* 3799 * If it's an inline extent, it can not have other extents 3800 * following it. 3801 */ 3802 if (btrfs_file_extent_type(path->nodes[0], ei) == 3803 BTRFS_FILE_EXTENT_INLINE) 3804 goto copy_inline_extent; 3805 3806 ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei); 3807 if (ext_len > aligned_end) 3808 return -EOPNOTSUPP; 3809 3810 ret = btrfs_next_item(root, path); 3811 if (ret < 0) { 3812 return ret; 3813 } else if (ret == 0) { 3814 btrfs_item_key_to_cpu(path->nodes[0], &key, 3815 path->slots[0]); 3816 if (key.objectid == btrfs_ino(BTRFS_I(dst)) && 3817 key.type == BTRFS_EXTENT_DATA_KEY) 3818 return -EOPNOTSUPP; 3819 } 3820 } 3821 3822 copy_inline_extent: 3823 /* 3824 * We have no extent items, or we have an extent at offset 0 which may 3825 * or may not be inlined. All these cases are dealt the same way. 3826 */ 3827 if (i_size_read(dst) > datal) { 3828 /* 3829 * If the destination inode has an inline extent... 3830 * This would require copying the data from the source inline 3831 * extent into the beginning of the destination's inline extent. 3832 * But this is really complex, both extents can be compressed 3833 * or just one of them, which would require decompressing and 3834 * re-compressing data (which could increase the new compressed 3835 * size, not allowing the compressed data to fit anymore in an 3836 * inline extent). 3837 * So just don't support this case for now (it should be rare, 3838 * we are not really saving space when cloning inline extents). 3839 */ 3840 return -EOPNOTSUPP; 3841 } 3842 3843 btrfs_release_path(path); 3844 ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1); 3845 if (ret) 3846 return ret; 3847 ret = btrfs_insert_empty_item(trans, root, path, new_key, size); 3848 if (ret) 3849 return ret; 3850 3851 if (skip) { 3852 const u32 start = btrfs_file_extent_calc_inline_size(0); 3853 3854 memmove(inline_data + start, inline_data + start + skip, datal); 3855 } 3856 3857 write_extent_buffer(path->nodes[0], inline_data, 3858 btrfs_item_ptr_offset(path->nodes[0], 3859 path->slots[0]), 3860 size); 3861 inode_add_bytes(dst, datal); 3862 3863 return 0; 3864 } 3865 3866 /** 3867 * btrfs_clone() - clone a range from inode file to another 3868 * 3869 * @src: Inode to clone from 3870 * @inode: Inode to clone to 3871 * @off: Offset within source to start clone from 3872 * @olen: Original length, passed by user, of range to clone 3873 * @olen_aligned: Block-aligned value of olen 3874 * @destoff: Offset within @inode to start clone 3875 * @no_time_update: Whether to update mtime/ctime on the target inode 3876 */ 3877 static int btrfs_clone(struct inode *src, struct inode *inode, 3878 const u64 off, const u64 olen, const u64 olen_aligned, 3879 const u64 destoff, int no_time_update) 3880 { 3881 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3882 struct btrfs_root *root = BTRFS_I(inode)->root; 3883 struct btrfs_path *path = NULL; 3884 struct extent_buffer *leaf; 3885 struct btrfs_trans_handle *trans; 3886 char *buf = NULL; 3887 struct btrfs_key key; 3888 u32 nritems; 3889 int slot; 3890 int ret; 3891 const u64 len = olen_aligned; 3892 u64 last_dest_end = destoff; 3893 3894 ret = -ENOMEM; 3895 buf = kvmalloc(fs_info->nodesize, GFP_KERNEL); 3896 if (!buf) 3897 return ret; 3898 3899 path = btrfs_alloc_path(); 3900 if (!path) { 3901 kvfree(buf); 3902 return ret; 3903 } 3904 3905 path->reada = READA_FORWARD; 3906 /* clone data */ 3907 key.objectid = btrfs_ino(BTRFS_I(src)); 3908 key.type = BTRFS_EXTENT_DATA_KEY; 3909 key.offset = off; 3910 3911 while (1) { 3912 u64 next_key_min_offset = key.offset + 1; 3913 3914 /* 3915 * note the key will change type as we walk through the 3916 * tree. 3917 */ 3918 path->leave_spinning = 1; 3919 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path, 3920 0, 0); 3921 if (ret < 0) 3922 goto out; 3923 /* 3924 * First search, if no extent item that starts at offset off was 3925 * found but the previous item is an extent item, it's possible 3926 * it might overlap our target range, therefore process it. 3927 */ 3928 if (key.offset == off && ret > 0 && path->slots[0] > 0) { 3929 btrfs_item_key_to_cpu(path->nodes[0], &key, 3930 path->slots[0] - 1); 3931 if (key.type == BTRFS_EXTENT_DATA_KEY) 3932 path->slots[0]--; 3933 } 3934 3935 nritems = btrfs_header_nritems(path->nodes[0]); 3936 process_slot: 3937 if (path->slots[0] >= nritems) { 3938 ret = btrfs_next_leaf(BTRFS_I(src)->root, path); 3939 if (ret < 0) 3940 goto out; 3941 if (ret > 0) 3942 break; 3943 nritems = btrfs_header_nritems(path->nodes[0]); 3944 } 3945 leaf = path->nodes[0]; 3946 slot = path->slots[0]; 3947 3948 btrfs_item_key_to_cpu(leaf, &key, slot); 3949 if (key.type > BTRFS_EXTENT_DATA_KEY || 3950 key.objectid != btrfs_ino(BTRFS_I(src))) 3951 break; 3952 3953 if (key.type == BTRFS_EXTENT_DATA_KEY) { 3954 struct btrfs_file_extent_item *extent; 3955 int type; 3956 u32 size; 3957 struct btrfs_key new_key; 3958 u64 disko = 0, diskl = 0; 3959 u64 datao = 0, datal = 0; 3960 u8 comp; 3961 u64 drop_start; 3962 3963 extent = btrfs_item_ptr(leaf, slot, 3964 struct btrfs_file_extent_item); 3965 comp = btrfs_file_extent_compression(leaf, extent); 3966 type = btrfs_file_extent_type(leaf, extent); 3967 if (type == BTRFS_FILE_EXTENT_REG || 3968 type == BTRFS_FILE_EXTENT_PREALLOC) { 3969 disko = btrfs_file_extent_disk_bytenr(leaf, 3970 extent); 3971 diskl = btrfs_file_extent_disk_num_bytes(leaf, 3972 extent); 3973 datao = btrfs_file_extent_offset(leaf, extent); 3974 datal = btrfs_file_extent_num_bytes(leaf, 3975 extent); 3976 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 3977 /* take upper bound, may be compressed */ 3978 datal = btrfs_file_extent_ram_bytes(leaf, 3979 extent); 3980 } 3981 3982 /* 3983 * The first search might have left us at an extent 3984 * item that ends before our target range's start, can 3985 * happen if we have holes and NO_HOLES feature enabled. 3986 */ 3987 if (key.offset + datal <= off) { 3988 path->slots[0]++; 3989 goto process_slot; 3990 } else if (key.offset >= off + len) { 3991 break; 3992 } 3993 next_key_min_offset = key.offset + datal; 3994 size = btrfs_item_size_nr(leaf, slot); 3995 read_extent_buffer(leaf, buf, 3996 btrfs_item_ptr_offset(leaf, slot), 3997 size); 3998 3999 btrfs_release_path(path); 4000 path->leave_spinning = 0; 4001 4002 memcpy(&new_key, &key, sizeof(new_key)); 4003 new_key.objectid = btrfs_ino(BTRFS_I(inode)); 4004 if (off <= key.offset) 4005 new_key.offset = key.offset + destoff - off; 4006 else 4007 new_key.offset = destoff; 4008 4009 /* 4010 * Deal with a hole that doesn't have an extent item 4011 * that represents it (NO_HOLES feature enabled). 4012 * This hole is either in the middle of the cloning 4013 * range or at the beginning (fully overlaps it or 4014 * partially overlaps it). 4015 */ 4016 if (new_key.offset != last_dest_end) 4017 drop_start = last_dest_end; 4018 else 4019 drop_start = new_key.offset; 4020 4021 /* 4022 * 1 - adjusting old extent (we may have to split it) 4023 * 1 - add new extent 4024 * 1 - inode update 4025 */ 4026 trans = btrfs_start_transaction(root, 3); 4027 if (IS_ERR(trans)) { 4028 ret = PTR_ERR(trans); 4029 goto out; 4030 } 4031 4032 if (type == BTRFS_FILE_EXTENT_REG || 4033 type == BTRFS_FILE_EXTENT_PREALLOC) { 4034 /* 4035 * a | --- range to clone ---| b 4036 * | ------------- extent ------------- | 4037 */ 4038 4039 /* subtract range b */ 4040 if (key.offset + datal > off + len) 4041 datal = off + len - key.offset; 4042 4043 /* subtract range a */ 4044 if (off > key.offset) { 4045 datao += off - key.offset; 4046 datal -= off - key.offset; 4047 } 4048 4049 ret = btrfs_drop_extents(trans, root, inode, 4050 drop_start, 4051 new_key.offset + datal, 4052 1); 4053 if (ret) { 4054 if (ret != -EOPNOTSUPP) 4055 btrfs_abort_transaction(trans, 4056 ret); 4057 btrfs_end_transaction(trans); 4058 goto out; 4059 } 4060 4061 ret = btrfs_insert_empty_item(trans, root, path, 4062 &new_key, size); 4063 if (ret) { 4064 btrfs_abort_transaction(trans, ret); 4065 btrfs_end_transaction(trans); 4066 goto out; 4067 } 4068 4069 leaf = path->nodes[0]; 4070 slot = path->slots[0]; 4071 write_extent_buffer(leaf, buf, 4072 btrfs_item_ptr_offset(leaf, slot), 4073 size); 4074 4075 extent = btrfs_item_ptr(leaf, slot, 4076 struct btrfs_file_extent_item); 4077 4078 /* disko == 0 means it's a hole */ 4079 if (!disko) 4080 datao = 0; 4081 4082 btrfs_set_file_extent_offset(leaf, extent, 4083 datao); 4084 btrfs_set_file_extent_num_bytes(leaf, extent, 4085 datal); 4086 4087 if (disko) { 4088 inode_add_bytes(inode, datal); 4089 ret = btrfs_inc_extent_ref(trans, 4090 root, 4091 disko, diskl, 0, 4092 root->root_key.objectid, 4093 btrfs_ino(BTRFS_I(inode)), 4094 new_key.offset - datao); 4095 if (ret) { 4096 btrfs_abort_transaction(trans, 4097 ret); 4098 btrfs_end_transaction(trans); 4099 goto out; 4100 4101 } 4102 } 4103 } else if (type == BTRFS_FILE_EXTENT_INLINE) { 4104 u64 skip = 0; 4105 u64 trim = 0; 4106 4107 if (off > key.offset) { 4108 skip = off - key.offset; 4109 new_key.offset += skip; 4110 } 4111 4112 if (key.offset + datal > off + len) 4113 trim = key.offset + datal - (off + len); 4114 4115 if (comp && (skip || trim)) { 4116 ret = -EINVAL; 4117 btrfs_end_transaction(trans); 4118 goto out; 4119 } 4120 size -= skip + trim; 4121 datal -= skip + trim; 4122 4123 ret = clone_copy_inline_extent(inode, 4124 trans, path, 4125 &new_key, 4126 drop_start, 4127 datal, 4128 skip, size, buf); 4129 if (ret) { 4130 if (ret != -EOPNOTSUPP) 4131 btrfs_abort_transaction(trans, 4132 ret); 4133 btrfs_end_transaction(trans); 4134 goto out; 4135 } 4136 leaf = path->nodes[0]; 4137 slot = path->slots[0]; 4138 } 4139 4140 /* If we have an implicit hole (NO_HOLES feature). */ 4141 if (drop_start < new_key.offset) 4142 clone_update_extent_map(BTRFS_I(inode), trans, 4143 NULL, drop_start, 4144 new_key.offset - drop_start); 4145 4146 clone_update_extent_map(BTRFS_I(inode), trans, 4147 path, 0, 0); 4148 4149 btrfs_mark_buffer_dirty(leaf); 4150 btrfs_release_path(path); 4151 4152 last_dest_end = ALIGN(new_key.offset + datal, 4153 fs_info->sectorsize); 4154 ret = clone_finish_inode_update(trans, inode, 4155 last_dest_end, 4156 destoff, olen, 4157 no_time_update); 4158 if (ret) 4159 goto out; 4160 if (new_key.offset + datal >= destoff + len) 4161 break; 4162 } 4163 btrfs_release_path(path); 4164 key.offset = next_key_min_offset; 4165 4166 if (fatal_signal_pending(current)) { 4167 ret = -EINTR; 4168 goto out; 4169 } 4170 } 4171 ret = 0; 4172 4173 if (last_dest_end < destoff + len) { 4174 /* 4175 * We have an implicit hole (NO_HOLES feature is enabled) that 4176 * fully or partially overlaps our cloning range at its end. 4177 */ 4178 btrfs_release_path(path); 4179 4180 /* 4181 * 1 - remove extent(s) 4182 * 1 - inode update 4183 */ 4184 trans = btrfs_start_transaction(root, 2); 4185 if (IS_ERR(trans)) { 4186 ret = PTR_ERR(trans); 4187 goto out; 4188 } 4189 ret = btrfs_drop_extents(trans, root, inode, 4190 last_dest_end, destoff + len, 1); 4191 if (ret) { 4192 if (ret != -EOPNOTSUPP) 4193 btrfs_abort_transaction(trans, ret); 4194 btrfs_end_transaction(trans); 4195 goto out; 4196 } 4197 clone_update_extent_map(BTRFS_I(inode), trans, NULL, 4198 last_dest_end, 4199 destoff + len - last_dest_end); 4200 ret = clone_finish_inode_update(trans, inode, destoff + len, 4201 destoff, olen, no_time_update); 4202 } 4203 4204 out: 4205 btrfs_free_path(path); 4206 kvfree(buf); 4207 return ret; 4208 } 4209 4210 static noinline int btrfs_clone_files(struct file *file, struct file *file_src, 4211 u64 off, u64 olen, u64 destoff) 4212 { 4213 struct inode *inode = file_inode(file); 4214 struct inode *src = file_inode(file_src); 4215 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 4216 struct btrfs_root *root = BTRFS_I(inode)->root; 4217 int ret; 4218 u64 len = olen; 4219 u64 bs = fs_info->sb->s_blocksize; 4220 int same_inode = src == inode; 4221 4222 /* 4223 * TODO: 4224 * - split compressed inline extents. annoying: we need to 4225 * decompress into destination's address_space (the file offset 4226 * may change, so source mapping won't do), then recompress (or 4227 * otherwise reinsert) a subrange. 4228 * 4229 * - split destination inode's inline extents. The inline extents can 4230 * be either compressed or non-compressed. 4231 */ 4232 4233 if (btrfs_root_readonly(root)) 4234 return -EROFS; 4235 4236 if (file_src->f_path.mnt != file->f_path.mnt || 4237 src->i_sb != inode->i_sb) 4238 return -EXDEV; 4239 4240 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 4241 return -EISDIR; 4242 4243 if (!same_inode) { 4244 btrfs_double_inode_lock(src, inode); 4245 } else { 4246 inode_lock(src); 4247 } 4248 4249 /* don't make the dst file partly checksummed */ 4250 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != 4251 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { 4252 ret = -EINVAL; 4253 goto out_unlock; 4254 } 4255 4256 /* determine range to clone */ 4257 ret = -EINVAL; 4258 if (off + len > src->i_size || off + len < off) 4259 goto out_unlock; 4260 if (len == 0) 4261 olen = len = src->i_size - off; 4262 /* 4263 * If we extend to eof, continue to block boundary if and only if the 4264 * destination end offset matches the destination file's size, otherwise 4265 * we would be corrupting data by placing the eof block into the middle 4266 * of a file. 4267 */ 4268 if (off + len == src->i_size) { 4269 if (!IS_ALIGNED(len, bs) && destoff + len < inode->i_size) 4270 goto out_unlock; 4271 len = ALIGN(src->i_size, bs) - off; 4272 } 4273 4274 if (len == 0) { 4275 ret = 0; 4276 goto out_unlock; 4277 } 4278 4279 /* verify the end result is block aligned */ 4280 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || 4281 !IS_ALIGNED(destoff, bs)) 4282 goto out_unlock; 4283 4284 /* verify if ranges are overlapped within the same file */ 4285 if (same_inode) { 4286 if (destoff + len > off && destoff < off + len) 4287 goto out_unlock; 4288 } 4289 4290 if (destoff > inode->i_size) { 4291 ret = btrfs_cont_expand(inode, inode->i_size, destoff); 4292 if (ret) 4293 goto out_unlock; 4294 } 4295 4296 /* 4297 * Lock the target range too. Right after we replace the file extent 4298 * items in the fs tree (which now point to the cloned data), we might 4299 * have a worker replace them with extent items relative to a write 4300 * operation that was issued before this clone operation (i.e. confront 4301 * with inode.c:btrfs_finish_ordered_io). 4302 */ 4303 if (same_inode) { 4304 u64 lock_start = min_t(u64, off, destoff); 4305 u64 lock_len = max_t(u64, off, destoff) + len - lock_start; 4306 4307 ret = lock_extent_range(src, lock_start, lock_len, true); 4308 } else { 4309 ret = btrfs_double_extent_lock(src, off, inode, destoff, len, 4310 true); 4311 } 4312 ASSERT(ret == 0); 4313 if (WARN_ON(ret)) { 4314 /* ranges in the io trees already unlocked */ 4315 goto out_unlock; 4316 } 4317 4318 ret = btrfs_clone(src, inode, off, olen, len, destoff, 0); 4319 4320 if (same_inode) { 4321 u64 lock_start = min_t(u64, off, destoff); 4322 u64 lock_end = max_t(u64, off, destoff) + len - 1; 4323 4324 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end); 4325 } else { 4326 btrfs_double_extent_unlock(src, off, inode, destoff, len); 4327 } 4328 /* 4329 * Truncate page cache pages so that future reads will see the cloned 4330 * data immediately and not the previous data. 4331 */ 4332 truncate_inode_pages_range(&inode->i_data, 4333 round_down(destoff, PAGE_SIZE), 4334 round_up(destoff + len, PAGE_SIZE) - 1); 4335 out_unlock: 4336 if (!same_inode) 4337 btrfs_double_inode_unlock(src, inode); 4338 else 4339 inode_unlock(src); 4340 return ret; 4341 } 4342 4343 loff_t btrfs_remap_file_range(struct file *src_file, loff_t off, 4344 struct file *dst_file, loff_t destoff, loff_t len, 4345 unsigned int remap_flags) 4346 { 4347 int ret; 4348 4349 if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY)) 4350 return -EINVAL; 4351 4352 if (remap_flags & REMAP_FILE_DEDUP) { 4353 struct inode *src = file_inode(src_file); 4354 struct inode *dst = file_inode(dst_file); 4355 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize; 4356 4357 if (WARN_ON_ONCE(bs < PAGE_SIZE)) { 4358 /* 4359 * Btrfs does not support blocksize < page_size. As a 4360 * result, btrfs_cmp_data() won't correctly handle 4361 * this situation without an update. 4362 */ 4363 return -EINVAL; 4364 } 4365 4366 ret = btrfs_extent_same(src, off, len, dst, destoff); 4367 } else { 4368 ret = btrfs_clone_files(dst_file, src_file, off, len, destoff); 4369 } 4370 return ret < 0 ? ret : len; 4371 } 4372 4373 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) 4374 { 4375 struct inode *inode = file_inode(file); 4376 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 4377 struct btrfs_root *root = BTRFS_I(inode)->root; 4378 struct btrfs_root *new_root; 4379 struct btrfs_dir_item *di; 4380 struct btrfs_trans_handle *trans; 4381 struct btrfs_path *path; 4382 struct btrfs_key location; 4383 struct btrfs_disk_key disk_key; 4384 u64 objectid = 0; 4385 u64 dir_id; 4386 int ret; 4387 4388 if (!capable(CAP_SYS_ADMIN)) 4389 return -EPERM; 4390 4391 ret = mnt_want_write_file(file); 4392 if (ret) 4393 return ret; 4394 4395 if (copy_from_user(&objectid, argp, sizeof(objectid))) { 4396 ret = -EFAULT; 4397 goto out; 4398 } 4399 4400 if (!objectid) 4401 objectid = BTRFS_FS_TREE_OBJECTID; 4402 4403 location.objectid = objectid; 4404 location.type = BTRFS_ROOT_ITEM_KEY; 4405 location.offset = (u64)-1; 4406 4407 new_root = btrfs_read_fs_root_no_name(fs_info, &location); 4408 if (IS_ERR(new_root)) { 4409 ret = PTR_ERR(new_root); 4410 goto out; 4411 } 4412 if (!is_fstree(new_root->root_key.objectid)) { 4413 ret = -ENOENT; 4414 goto out; 4415 } 4416 4417 path = btrfs_alloc_path(); 4418 if (!path) { 4419 ret = -ENOMEM; 4420 goto out; 4421 } 4422 path->leave_spinning = 1; 4423 4424 trans = btrfs_start_transaction(root, 1); 4425 if (IS_ERR(trans)) { 4426 btrfs_free_path(path); 4427 ret = PTR_ERR(trans); 4428 goto out; 4429 } 4430 4431 dir_id = btrfs_super_root_dir(fs_info->super_copy); 4432 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path, 4433 dir_id, "default", 7, 1); 4434 if (IS_ERR_OR_NULL(di)) { 4435 btrfs_free_path(path); 4436 btrfs_end_transaction(trans); 4437 btrfs_err(fs_info, 4438 "Umm, you don't have the default diritem, this isn't going to work"); 4439 ret = -ENOENT; 4440 goto out; 4441 } 4442 4443 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); 4444 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); 4445 btrfs_mark_buffer_dirty(path->nodes[0]); 4446 btrfs_free_path(path); 4447 4448 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL); 4449 btrfs_end_transaction(trans); 4450 out: 4451 mnt_drop_write_file(file); 4452 return ret; 4453 } 4454 4455 static void get_block_group_info(struct list_head *groups_list, 4456 struct btrfs_ioctl_space_info *space) 4457 { 4458 struct btrfs_block_group_cache *block_group; 4459 4460 space->total_bytes = 0; 4461 space->used_bytes = 0; 4462 space->flags = 0; 4463 list_for_each_entry(block_group, groups_list, list) { 4464 space->flags = block_group->flags; 4465 space->total_bytes += block_group->key.offset; 4466 space->used_bytes += 4467 btrfs_block_group_used(&block_group->item); 4468 } 4469 } 4470 4471 static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info, 4472 void __user *arg) 4473 { 4474 struct btrfs_ioctl_space_args space_args; 4475 struct btrfs_ioctl_space_info space; 4476 struct btrfs_ioctl_space_info *dest; 4477 struct btrfs_ioctl_space_info *dest_orig; 4478 struct btrfs_ioctl_space_info __user *user_dest; 4479 struct btrfs_space_info *info; 4480 static const u64 types[] = { 4481 BTRFS_BLOCK_GROUP_DATA, 4482 BTRFS_BLOCK_GROUP_SYSTEM, 4483 BTRFS_BLOCK_GROUP_METADATA, 4484 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA 4485 }; 4486 int num_types = 4; 4487 int alloc_size; 4488 int ret = 0; 4489 u64 slot_count = 0; 4490 int i, c; 4491 4492 if (copy_from_user(&space_args, 4493 (struct btrfs_ioctl_space_args __user *)arg, 4494 sizeof(space_args))) 4495 return -EFAULT; 4496 4497 for (i = 0; i < num_types; i++) { 4498 struct btrfs_space_info *tmp; 4499 4500 info = NULL; 4501 rcu_read_lock(); 4502 list_for_each_entry_rcu(tmp, &fs_info->space_info, 4503 list) { 4504 if (tmp->flags == types[i]) { 4505 info = tmp; 4506 break; 4507 } 4508 } 4509 rcu_read_unlock(); 4510 4511 if (!info) 4512 continue; 4513 4514 down_read(&info->groups_sem); 4515 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 4516 if (!list_empty(&info->block_groups[c])) 4517 slot_count++; 4518 } 4519 up_read(&info->groups_sem); 4520 } 4521 4522 /* 4523 * Global block reserve, exported as a space_info 4524 */ 4525 slot_count++; 4526 4527 /* space_slots == 0 means they are asking for a count */ 4528 if (space_args.space_slots == 0) { 4529 space_args.total_spaces = slot_count; 4530 goto out; 4531 } 4532 4533 slot_count = min_t(u64, space_args.space_slots, slot_count); 4534 4535 alloc_size = sizeof(*dest) * slot_count; 4536 4537 /* we generally have at most 6 or so space infos, one for each raid 4538 * level. So, a whole page should be more than enough for everyone 4539 */ 4540 if (alloc_size > PAGE_SIZE) 4541 return -ENOMEM; 4542 4543 space_args.total_spaces = 0; 4544 dest = kmalloc(alloc_size, GFP_KERNEL); 4545 if (!dest) 4546 return -ENOMEM; 4547 dest_orig = dest; 4548 4549 /* now we have a buffer to copy into */ 4550 for (i = 0; i < num_types; i++) { 4551 struct btrfs_space_info *tmp; 4552 4553 if (!slot_count) 4554 break; 4555 4556 info = NULL; 4557 rcu_read_lock(); 4558 list_for_each_entry_rcu(tmp, &fs_info->space_info, 4559 list) { 4560 if (tmp->flags == types[i]) { 4561 info = tmp; 4562 break; 4563 } 4564 } 4565 rcu_read_unlock(); 4566 4567 if (!info) 4568 continue; 4569 down_read(&info->groups_sem); 4570 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { 4571 if (!list_empty(&info->block_groups[c])) { 4572 get_block_group_info(&info->block_groups[c], 4573 &space); 4574 memcpy(dest, &space, sizeof(space)); 4575 dest++; 4576 space_args.total_spaces++; 4577 slot_count--; 4578 } 4579 if (!slot_count) 4580 break; 4581 } 4582 up_read(&info->groups_sem); 4583 } 4584 4585 /* 4586 * Add global block reserve 4587 */ 4588 if (slot_count) { 4589 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; 4590 4591 spin_lock(&block_rsv->lock); 4592 space.total_bytes = block_rsv->size; 4593 space.used_bytes = block_rsv->size - block_rsv->reserved; 4594 spin_unlock(&block_rsv->lock); 4595 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV; 4596 memcpy(dest, &space, sizeof(space)); 4597 space_args.total_spaces++; 4598 } 4599 4600 user_dest = (struct btrfs_ioctl_space_info __user *) 4601 (arg + sizeof(struct btrfs_ioctl_space_args)); 4602 4603 if (copy_to_user(user_dest, dest_orig, alloc_size)) 4604 ret = -EFAULT; 4605 4606 kfree(dest_orig); 4607 out: 4608 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) 4609 ret = -EFAULT; 4610 4611 return ret; 4612 } 4613 4614 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root, 4615 void __user *argp) 4616 { 4617 struct btrfs_trans_handle *trans; 4618 u64 transid; 4619 int ret; 4620 4621 trans = btrfs_attach_transaction_barrier(root); 4622 if (IS_ERR(trans)) { 4623 if (PTR_ERR(trans) != -ENOENT) 4624 return PTR_ERR(trans); 4625 4626 /* No running transaction, don't bother */ 4627 transid = root->fs_info->last_trans_committed; 4628 goto out; 4629 } 4630 transid = trans->transid; 4631 ret = btrfs_commit_transaction_async(trans, 0); 4632 if (ret) { 4633 btrfs_end_transaction(trans); 4634 return ret; 4635 } 4636 out: 4637 if (argp) 4638 if (copy_to_user(argp, &transid, sizeof(transid))) 4639 return -EFAULT; 4640 return 0; 4641 } 4642 4643 static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info, 4644 void __user *argp) 4645 { 4646 u64 transid; 4647 4648 if (argp) { 4649 if (copy_from_user(&transid, argp, sizeof(transid))) 4650 return -EFAULT; 4651 } else { 4652 transid = 0; /* current trans */ 4653 } 4654 return btrfs_wait_for_commit(fs_info, transid); 4655 } 4656 4657 static long btrfs_ioctl_scrub(struct file *file, void __user *arg) 4658 { 4659 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb); 4660 struct btrfs_ioctl_scrub_args *sa; 4661 int ret; 4662 4663 if (!capable(CAP_SYS_ADMIN)) 4664 return -EPERM; 4665 4666 sa = memdup_user(arg, sizeof(*sa)); 4667 if (IS_ERR(sa)) 4668 return PTR_ERR(sa); 4669 4670 if (!(sa->flags & BTRFS_SCRUB_READONLY)) { 4671 ret = mnt_want_write_file(file); 4672 if (ret) 4673 goto out; 4674 } 4675 4676 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end, 4677 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY, 4678 0); 4679 4680 if (copy_to_user(arg, sa, sizeof(*sa))) 4681 ret = -EFAULT; 4682 4683 if (!(sa->flags & BTRFS_SCRUB_READONLY)) 4684 mnt_drop_write_file(file); 4685 out: 4686 kfree(sa); 4687 return ret; 4688 } 4689 4690 static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info) 4691 { 4692 if (!capable(CAP_SYS_ADMIN)) 4693 return -EPERM; 4694 4695 return btrfs_scrub_cancel(fs_info); 4696 } 4697 4698 static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info, 4699 void __user *arg) 4700 { 4701 struct btrfs_ioctl_scrub_args *sa; 4702 int ret; 4703 4704 if (!capable(CAP_SYS_ADMIN)) 4705 return -EPERM; 4706 4707 sa = memdup_user(arg, sizeof(*sa)); 4708 if (IS_ERR(sa)) 4709 return PTR_ERR(sa); 4710 4711 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress); 4712 4713 if (copy_to_user(arg, sa, sizeof(*sa))) 4714 ret = -EFAULT; 4715 4716 kfree(sa); 4717 return ret; 4718 } 4719 4720 static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info, 4721 void __user *arg) 4722 { 4723 struct btrfs_ioctl_get_dev_stats *sa; 4724 int ret; 4725 4726 sa = memdup_user(arg, sizeof(*sa)); 4727 if (IS_ERR(sa)) 4728 return PTR_ERR(sa); 4729 4730 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) { 4731 kfree(sa); 4732 return -EPERM; 4733 } 4734 4735 ret = btrfs_get_dev_stats(fs_info, sa); 4736 4737 if (copy_to_user(arg, sa, sizeof(*sa))) 4738 ret = -EFAULT; 4739 4740 kfree(sa); 4741 return ret; 4742 } 4743 4744 static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info, 4745 void __user *arg) 4746 { 4747 struct btrfs_ioctl_dev_replace_args *p; 4748 int ret; 4749 4750 if (!capable(CAP_SYS_ADMIN)) 4751 return -EPERM; 4752 4753 p = memdup_user(arg, sizeof(*p)); 4754 if (IS_ERR(p)) 4755 return PTR_ERR(p); 4756 4757 switch (p->cmd) { 4758 case BTRFS_IOCTL_DEV_REPLACE_CMD_START: 4759 if (sb_rdonly(fs_info->sb)) { 4760 ret = -EROFS; 4761 goto out; 4762 } 4763 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { 4764 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 4765 } else { 4766 ret = btrfs_dev_replace_by_ioctl(fs_info, p); 4767 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 4768 } 4769 break; 4770 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS: 4771 btrfs_dev_replace_status(fs_info, p); 4772 ret = 0; 4773 break; 4774 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL: 4775 p->result = btrfs_dev_replace_cancel(fs_info); 4776 ret = 0; 4777 break; 4778 default: 4779 ret = -EINVAL; 4780 break; 4781 } 4782 4783 if (copy_to_user(arg, p, sizeof(*p))) 4784 ret = -EFAULT; 4785 out: 4786 kfree(p); 4787 return ret; 4788 } 4789 4790 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) 4791 { 4792 int ret = 0; 4793 int i; 4794 u64 rel_ptr; 4795 int size; 4796 struct btrfs_ioctl_ino_path_args *ipa = NULL; 4797 struct inode_fs_paths *ipath = NULL; 4798 struct btrfs_path *path; 4799 4800 if (!capable(CAP_DAC_READ_SEARCH)) 4801 return -EPERM; 4802 4803 path = btrfs_alloc_path(); 4804 if (!path) { 4805 ret = -ENOMEM; 4806 goto out; 4807 } 4808 4809 ipa = memdup_user(arg, sizeof(*ipa)); 4810 if (IS_ERR(ipa)) { 4811 ret = PTR_ERR(ipa); 4812 ipa = NULL; 4813 goto out; 4814 } 4815 4816 size = min_t(u32, ipa->size, 4096); 4817 ipath = init_ipath(size, root, path); 4818 if (IS_ERR(ipath)) { 4819 ret = PTR_ERR(ipath); 4820 ipath = NULL; 4821 goto out; 4822 } 4823 4824 ret = paths_from_inode(ipa->inum, ipath); 4825 if (ret < 0) 4826 goto out; 4827 4828 for (i = 0; i < ipath->fspath->elem_cnt; ++i) { 4829 rel_ptr = ipath->fspath->val[i] - 4830 (u64)(unsigned long)ipath->fspath->val; 4831 ipath->fspath->val[i] = rel_ptr; 4832 } 4833 4834 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath, 4835 ipath->fspath, size); 4836 if (ret) { 4837 ret = -EFAULT; 4838 goto out; 4839 } 4840 4841 out: 4842 btrfs_free_path(path); 4843 free_ipath(ipath); 4844 kfree(ipa); 4845 4846 return ret; 4847 } 4848 4849 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) 4850 { 4851 struct btrfs_data_container *inodes = ctx; 4852 const size_t c = 3 * sizeof(u64); 4853 4854 if (inodes->bytes_left >= c) { 4855 inodes->bytes_left -= c; 4856 inodes->val[inodes->elem_cnt] = inum; 4857 inodes->val[inodes->elem_cnt + 1] = offset; 4858 inodes->val[inodes->elem_cnt + 2] = root; 4859 inodes->elem_cnt += 3; 4860 } else { 4861 inodes->bytes_missing += c - inodes->bytes_left; 4862 inodes->bytes_left = 0; 4863 inodes->elem_missed += 3; 4864 } 4865 4866 return 0; 4867 } 4868 4869 static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info, 4870 void __user *arg, int version) 4871 { 4872 int ret = 0; 4873 int size; 4874 struct btrfs_ioctl_logical_ino_args *loi; 4875 struct btrfs_data_container *inodes = NULL; 4876 struct btrfs_path *path = NULL; 4877 bool ignore_offset; 4878 4879 if (!capable(CAP_SYS_ADMIN)) 4880 return -EPERM; 4881 4882 loi = memdup_user(arg, sizeof(*loi)); 4883 if (IS_ERR(loi)) 4884 return PTR_ERR(loi); 4885 4886 if (version == 1) { 4887 ignore_offset = false; 4888 size = min_t(u32, loi->size, SZ_64K); 4889 } else { 4890 /* All reserved bits must be 0 for now */ 4891 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) { 4892 ret = -EINVAL; 4893 goto out_loi; 4894 } 4895 /* Only accept flags we have defined so far */ 4896 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) { 4897 ret = -EINVAL; 4898 goto out_loi; 4899 } 4900 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET; 4901 size = min_t(u32, loi->size, SZ_16M); 4902 } 4903 4904 path = btrfs_alloc_path(); 4905 if (!path) { 4906 ret = -ENOMEM; 4907 goto out; 4908 } 4909 4910 inodes = init_data_container(size); 4911 if (IS_ERR(inodes)) { 4912 ret = PTR_ERR(inodes); 4913 inodes = NULL; 4914 goto out; 4915 } 4916 4917 ret = iterate_inodes_from_logical(loi->logical, fs_info, path, 4918 build_ino_list, inodes, ignore_offset); 4919 if (ret == -EINVAL) 4920 ret = -ENOENT; 4921 if (ret < 0) 4922 goto out; 4923 4924 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes, 4925 size); 4926 if (ret) 4927 ret = -EFAULT; 4928 4929 out: 4930 btrfs_free_path(path); 4931 kvfree(inodes); 4932 out_loi: 4933 kfree(loi); 4934 4935 return ret; 4936 } 4937 4938 void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info, 4939 struct btrfs_ioctl_balance_args *bargs) 4940 { 4941 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 4942 4943 bargs->flags = bctl->flags; 4944 4945 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) 4946 bargs->state |= BTRFS_BALANCE_STATE_RUNNING; 4947 if (atomic_read(&fs_info->balance_pause_req)) 4948 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; 4949 if (atomic_read(&fs_info->balance_cancel_req)) 4950 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; 4951 4952 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); 4953 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); 4954 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); 4955 4956 spin_lock(&fs_info->balance_lock); 4957 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); 4958 spin_unlock(&fs_info->balance_lock); 4959 } 4960 4961 static long btrfs_ioctl_balance(struct file *file, void __user *arg) 4962 { 4963 struct btrfs_root *root = BTRFS_I(file_inode(file))->root; 4964 struct btrfs_fs_info *fs_info = root->fs_info; 4965 struct btrfs_ioctl_balance_args *bargs; 4966 struct btrfs_balance_control *bctl; 4967 bool need_unlock; /* for mut. excl. ops lock */ 4968 int ret; 4969 4970 if (!capable(CAP_SYS_ADMIN)) 4971 return -EPERM; 4972 4973 ret = mnt_want_write_file(file); 4974 if (ret) 4975 return ret; 4976 4977 again: 4978 if (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { 4979 mutex_lock(&fs_info->balance_mutex); 4980 need_unlock = true; 4981 goto locked; 4982 } 4983 4984 /* 4985 * mut. excl. ops lock is locked. Three possibilities: 4986 * (1) some other op is running 4987 * (2) balance is running 4988 * (3) balance is paused -- special case (think resume) 4989 */ 4990 mutex_lock(&fs_info->balance_mutex); 4991 if (fs_info->balance_ctl) { 4992 /* this is either (2) or (3) */ 4993 if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { 4994 mutex_unlock(&fs_info->balance_mutex); 4995 /* 4996 * Lock released to allow other waiters to continue, 4997 * we'll reexamine the status again. 4998 */ 4999 mutex_lock(&fs_info->balance_mutex); 5000 5001 if (fs_info->balance_ctl && 5002 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { 5003 /* this is (3) */ 5004 need_unlock = false; 5005 goto locked; 5006 } 5007 5008 mutex_unlock(&fs_info->balance_mutex); 5009 goto again; 5010 } else { 5011 /* this is (2) */ 5012 mutex_unlock(&fs_info->balance_mutex); 5013 ret = -EINPROGRESS; 5014 goto out; 5015 } 5016 } else { 5017 /* this is (1) */ 5018 mutex_unlock(&fs_info->balance_mutex); 5019 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; 5020 goto out; 5021 } 5022 5023 locked: 5024 BUG_ON(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)); 5025 5026 if (arg) { 5027 bargs = memdup_user(arg, sizeof(*bargs)); 5028 if (IS_ERR(bargs)) { 5029 ret = PTR_ERR(bargs); 5030 goto out_unlock; 5031 } 5032 5033 if (bargs->flags & BTRFS_BALANCE_RESUME) { 5034 if (!fs_info->balance_ctl) { 5035 ret = -ENOTCONN; 5036 goto out_bargs; 5037 } 5038 5039 bctl = fs_info->balance_ctl; 5040 spin_lock(&fs_info->balance_lock); 5041 bctl->flags |= BTRFS_BALANCE_RESUME; 5042 spin_unlock(&fs_info->balance_lock); 5043 5044 goto do_balance; 5045 } 5046 } else { 5047 bargs = NULL; 5048 } 5049 5050 if (fs_info->balance_ctl) { 5051 ret = -EINPROGRESS; 5052 goto out_bargs; 5053 } 5054 5055 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL); 5056 if (!bctl) { 5057 ret = -ENOMEM; 5058 goto out_bargs; 5059 } 5060 5061 if (arg) { 5062 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); 5063 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); 5064 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); 5065 5066 bctl->flags = bargs->flags; 5067 } else { 5068 /* balance everything - no filters */ 5069 bctl->flags |= BTRFS_BALANCE_TYPE_MASK; 5070 } 5071 5072 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) { 5073 ret = -EINVAL; 5074 goto out_bctl; 5075 } 5076 5077 do_balance: 5078 /* 5079 * Ownership of bctl and filesystem flag BTRFS_FS_EXCL_OP goes to 5080 * btrfs_balance. bctl is freed in reset_balance_state, or, if 5081 * restriper was paused all the way until unmount, in free_fs_info. 5082 * The flag should be cleared after reset_balance_state. 5083 */ 5084 need_unlock = false; 5085 5086 ret = btrfs_balance(fs_info, bctl, bargs); 5087 bctl = NULL; 5088 5089 if (arg) { 5090 if (copy_to_user(arg, bargs, sizeof(*bargs))) 5091 ret = -EFAULT; 5092 } 5093 5094 out_bctl: 5095 kfree(bctl); 5096 out_bargs: 5097 kfree(bargs); 5098 out_unlock: 5099 mutex_unlock(&fs_info->balance_mutex); 5100 if (need_unlock) 5101 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 5102 out: 5103 mnt_drop_write_file(file); 5104 return ret; 5105 } 5106 5107 static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd) 5108 { 5109 if (!capable(CAP_SYS_ADMIN)) 5110 return -EPERM; 5111 5112 switch (cmd) { 5113 case BTRFS_BALANCE_CTL_PAUSE: 5114 return btrfs_pause_balance(fs_info); 5115 case BTRFS_BALANCE_CTL_CANCEL: 5116 return btrfs_cancel_balance(fs_info); 5117 } 5118 5119 return -EINVAL; 5120 } 5121 5122 static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info, 5123 void __user *arg) 5124 { 5125 struct btrfs_ioctl_balance_args *bargs; 5126 int ret = 0; 5127 5128 if (!capable(CAP_SYS_ADMIN)) 5129 return -EPERM; 5130 5131 mutex_lock(&fs_info->balance_mutex); 5132 if (!fs_info->balance_ctl) { 5133 ret = -ENOTCONN; 5134 goto out; 5135 } 5136 5137 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL); 5138 if (!bargs) { 5139 ret = -ENOMEM; 5140 goto out; 5141 } 5142 5143 btrfs_update_ioctl_balance_args(fs_info, bargs); 5144 5145 if (copy_to_user(arg, bargs, sizeof(*bargs))) 5146 ret = -EFAULT; 5147 5148 kfree(bargs); 5149 out: 5150 mutex_unlock(&fs_info->balance_mutex); 5151 return ret; 5152 } 5153 5154 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg) 5155 { 5156 struct inode *inode = file_inode(file); 5157 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5158 struct btrfs_ioctl_quota_ctl_args *sa; 5159 int ret; 5160 5161 if (!capable(CAP_SYS_ADMIN)) 5162 return -EPERM; 5163 5164 ret = mnt_want_write_file(file); 5165 if (ret) 5166 return ret; 5167 5168 sa = memdup_user(arg, sizeof(*sa)); 5169 if (IS_ERR(sa)) { 5170 ret = PTR_ERR(sa); 5171 goto drop_write; 5172 } 5173 5174 down_write(&fs_info->subvol_sem); 5175 5176 switch (sa->cmd) { 5177 case BTRFS_QUOTA_CTL_ENABLE: 5178 ret = btrfs_quota_enable(fs_info); 5179 break; 5180 case BTRFS_QUOTA_CTL_DISABLE: 5181 ret = btrfs_quota_disable(fs_info); 5182 break; 5183 default: 5184 ret = -EINVAL; 5185 break; 5186 } 5187 5188 kfree(sa); 5189 up_write(&fs_info->subvol_sem); 5190 drop_write: 5191 mnt_drop_write_file(file); 5192 return ret; 5193 } 5194 5195 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg) 5196 { 5197 struct inode *inode = file_inode(file); 5198 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5199 struct btrfs_root *root = BTRFS_I(inode)->root; 5200 struct btrfs_ioctl_qgroup_assign_args *sa; 5201 struct btrfs_trans_handle *trans; 5202 int ret; 5203 int err; 5204 5205 if (!capable(CAP_SYS_ADMIN)) 5206 return -EPERM; 5207 5208 ret = mnt_want_write_file(file); 5209 if (ret) 5210 return ret; 5211 5212 sa = memdup_user(arg, sizeof(*sa)); 5213 if (IS_ERR(sa)) { 5214 ret = PTR_ERR(sa); 5215 goto drop_write; 5216 } 5217 5218 trans = btrfs_join_transaction(root); 5219 if (IS_ERR(trans)) { 5220 ret = PTR_ERR(trans); 5221 goto out; 5222 } 5223 5224 if (sa->assign) { 5225 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst); 5226 } else { 5227 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst); 5228 } 5229 5230 /* update qgroup status and info */ 5231 err = btrfs_run_qgroups(trans); 5232 if (err < 0) 5233 btrfs_handle_fs_error(fs_info, err, 5234 "failed to update qgroup status and info"); 5235 err = btrfs_end_transaction(trans); 5236 if (err && !ret) 5237 ret = err; 5238 5239 out: 5240 kfree(sa); 5241 drop_write: 5242 mnt_drop_write_file(file); 5243 return ret; 5244 } 5245 5246 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg) 5247 { 5248 struct inode *inode = file_inode(file); 5249 struct btrfs_root *root = BTRFS_I(inode)->root; 5250 struct btrfs_ioctl_qgroup_create_args *sa; 5251 struct btrfs_trans_handle *trans; 5252 int ret; 5253 int err; 5254 5255 if (!capable(CAP_SYS_ADMIN)) 5256 return -EPERM; 5257 5258 ret = mnt_want_write_file(file); 5259 if (ret) 5260 return ret; 5261 5262 sa = memdup_user(arg, sizeof(*sa)); 5263 if (IS_ERR(sa)) { 5264 ret = PTR_ERR(sa); 5265 goto drop_write; 5266 } 5267 5268 if (!sa->qgroupid) { 5269 ret = -EINVAL; 5270 goto out; 5271 } 5272 5273 trans = btrfs_join_transaction(root); 5274 if (IS_ERR(trans)) { 5275 ret = PTR_ERR(trans); 5276 goto out; 5277 } 5278 5279 if (sa->create) { 5280 ret = btrfs_create_qgroup(trans, sa->qgroupid); 5281 } else { 5282 ret = btrfs_remove_qgroup(trans, sa->qgroupid); 5283 } 5284 5285 err = btrfs_end_transaction(trans); 5286 if (err && !ret) 5287 ret = err; 5288 5289 out: 5290 kfree(sa); 5291 drop_write: 5292 mnt_drop_write_file(file); 5293 return ret; 5294 } 5295 5296 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg) 5297 { 5298 struct inode *inode = file_inode(file); 5299 struct btrfs_root *root = BTRFS_I(inode)->root; 5300 struct btrfs_ioctl_qgroup_limit_args *sa; 5301 struct btrfs_trans_handle *trans; 5302 int ret; 5303 int err; 5304 u64 qgroupid; 5305 5306 if (!capable(CAP_SYS_ADMIN)) 5307 return -EPERM; 5308 5309 ret = mnt_want_write_file(file); 5310 if (ret) 5311 return ret; 5312 5313 sa = memdup_user(arg, sizeof(*sa)); 5314 if (IS_ERR(sa)) { 5315 ret = PTR_ERR(sa); 5316 goto drop_write; 5317 } 5318 5319 trans = btrfs_join_transaction(root); 5320 if (IS_ERR(trans)) { 5321 ret = PTR_ERR(trans); 5322 goto out; 5323 } 5324 5325 qgroupid = sa->qgroupid; 5326 if (!qgroupid) { 5327 /* take the current subvol as qgroup */ 5328 qgroupid = root->root_key.objectid; 5329 } 5330 5331 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim); 5332 5333 err = btrfs_end_transaction(trans); 5334 if (err && !ret) 5335 ret = err; 5336 5337 out: 5338 kfree(sa); 5339 drop_write: 5340 mnt_drop_write_file(file); 5341 return ret; 5342 } 5343 5344 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg) 5345 { 5346 struct inode *inode = file_inode(file); 5347 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5348 struct btrfs_ioctl_quota_rescan_args *qsa; 5349 int ret; 5350 5351 if (!capable(CAP_SYS_ADMIN)) 5352 return -EPERM; 5353 5354 ret = mnt_want_write_file(file); 5355 if (ret) 5356 return ret; 5357 5358 qsa = memdup_user(arg, sizeof(*qsa)); 5359 if (IS_ERR(qsa)) { 5360 ret = PTR_ERR(qsa); 5361 goto drop_write; 5362 } 5363 5364 if (qsa->flags) { 5365 ret = -EINVAL; 5366 goto out; 5367 } 5368 5369 ret = btrfs_qgroup_rescan(fs_info); 5370 5371 out: 5372 kfree(qsa); 5373 drop_write: 5374 mnt_drop_write_file(file); 5375 return ret; 5376 } 5377 5378 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg) 5379 { 5380 struct inode *inode = file_inode(file); 5381 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5382 struct btrfs_ioctl_quota_rescan_args *qsa; 5383 int ret = 0; 5384 5385 if (!capable(CAP_SYS_ADMIN)) 5386 return -EPERM; 5387 5388 qsa = kzalloc(sizeof(*qsa), GFP_KERNEL); 5389 if (!qsa) 5390 return -ENOMEM; 5391 5392 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { 5393 qsa->flags = 1; 5394 qsa->progress = fs_info->qgroup_rescan_progress.objectid; 5395 } 5396 5397 if (copy_to_user(arg, qsa, sizeof(*qsa))) 5398 ret = -EFAULT; 5399 5400 kfree(qsa); 5401 return ret; 5402 } 5403 5404 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg) 5405 { 5406 struct inode *inode = file_inode(file); 5407 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5408 5409 if (!capable(CAP_SYS_ADMIN)) 5410 return -EPERM; 5411 5412 return btrfs_qgroup_wait_for_completion(fs_info, true); 5413 } 5414 5415 static long _btrfs_ioctl_set_received_subvol(struct file *file, 5416 struct btrfs_ioctl_received_subvol_args *sa) 5417 { 5418 struct inode *inode = file_inode(file); 5419 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5420 struct btrfs_root *root = BTRFS_I(inode)->root; 5421 struct btrfs_root_item *root_item = &root->root_item; 5422 struct btrfs_trans_handle *trans; 5423 struct timespec64 ct = current_time(inode); 5424 int ret = 0; 5425 int received_uuid_changed; 5426 5427 if (!inode_owner_or_capable(inode)) 5428 return -EPERM; 5429 5430 ret = mnt_want_write_file(file); 5431 if (ret < 0) 5432 return ret; 5433 5434 down_write(&fs_info->subvol_sem); 5435 5436 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { 5437 ret = -EINVAL; 5438 goto out; 5439 } 5440 5441 if (btrfs_root_readonly(root)) { 5442 ret = -EROFS; 5443 goto out; 5444 } 5445 5446 /* 5447 * 1 - root item 5448 * 2 - uuid items (received uuid + subvol uuid) 5449 */ 5450 trans = btrfs_start_transaction(root, 3); 5451 if (IS_ERR(trans)) { 5452 ret = PTR_ERR(trans); 5453 trans = NULL; 5454 goto out; 5455 } 5456 5457 sa->rtransid = trans->transid; 5458 sa->rtime.sec = ct.tv_sec; 5459 sa->rtime.nsec = ct.tv_nsec; 5460 5461 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid, 5462 BTRFS_UUID_SIZE); 5463 if (received_uuid_changed && 5464 !btrfs_is_empty_uuid(root_item->received_uuid)) { 5465 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid, 5466 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 5467 root->root_key.objectid); 5468 if (ret && ret != -ENOENT) { 5469 btrfs_abort_transaction(trans, ret); 5470 btrfs_end_transaction(trans); 5471 goto out; 5472 } 5473 } 5474 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); 5475 btrfs_set_root_stransid(root_item, sa->stransid); 5476 btrfs_set_root_rtransid(root_item, sa->rtransid); 5477 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec); 5478 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec); 5479 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec); 5480 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec); 5481 5482 ret = btrfs_update_root(trans, fs_info->tree_root, 5483 &root->root_key, &root->root_item); 5484 if (ret < 0) { 5485 btrfs_end_transaction(trans); 5486 goto out; 5487 } 5488 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) { 5489 ret = btrfs_uuid_tree_add(trans, sa->uuid, 5490 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 5491 root->root_key.objectid); 5492 if (ret < 0 && ret != -EEXIST) { 5493 btrfs_abort_transaction(trans, ret); 5494 btrfs_end_transaction(trans); 5495 goto out; 5496 } 5497 } 5498 ret = btrfs_commit_transaction(trans); 5499 out: 5500 up_write(&fs_info->subvol_sem); 5501 mnt_drop_write_file(file); 5502 return ret; 5503 } 5504 5505 #ifdef CONFIG_64BIT 5506 static long btrfs_ioctl_set_received_subvol_32(struct file *file, 5507 void __user *arg) 5508 { 5509 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL; 5510 struct btrfs_ioctl_received_subvol_args *args64 = NULL; 5511 int ret = 0; 5512 5513 args32 = memdup_user(arg, sizeof(*args32)); 5514 if (IS_ERR(args32)) 5515 return PTR_ERR(args32); 5516 5517 args64 = kmalloc(sizeof(*args64), GFP_KERNEL); 5518 if (!args64) { 5519 ret = -ENOMEM; 5520 goto out; 5521 } 5522 5523 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE); 5524 args64->stransid = args32->stransid; 5525 args64->rtransid = args32->rtransid; 5526 args64->stime.sec = args32->stime.sec; 5527 args64->stime.nsec = args32->stime.nsec; 5528 args64->rtime.sec = args32->rtime.sec; 5529 args64->rtime.nsec = args32->rtime.nsec; 5530 args64->flags = args32->flags; 5531 5532 ret = _btrfs_ioctl_set_received_subvol(file, args64); 5533 if (ret) 5534 goto out; 5535 5536 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE); 5537 args32->stransid = args64->stransid; 5538 args32->rtransid = args64->rtransid; 5539 args32->stime.sec = args64->stime.sec; 5540 args32->stime.nsec = args64->stime.nsec; 5541 args32->rtime.sec = args64->rtime.sec; 5542 args32->rtime.nsec = args64->rtime.nsec; 5543 args32->flags = args64->flags; 5544 5545 ret = copy_to_user(arg, args32, sizeof(*args32)); 5546 if (ret) 5547 ret = -EFAULT; 5548 5549 out: 5550 kfree(args32); 5551 kfree(args64); 5552 return ret; 5553 } 5554 #endif 5555 5556 static long btrfs_ioctl_set_received_subvol(struct file *file, 5557 void __user *arg) 5558 { 5559 struct btrfs_ioctl_received_subvol_args *sa = NULL; 5560 int ret = 0; 5561 5562 sa = memdup_user(arg, sizeof(*sa)); 5563 if (IS_ERR(sa)) 5564 return PTR_ERR(sa); 5565 5566 ret = _btrfs_ioctl_set_received_subvol(file, sa); 5567 5568 if (ret) 5569 goto out; 5570 5571 ret = copy_to_user(arg, sa, sizeof(*sa)); 5572 if (ret) 5573 ret = -EFAULT; 5574 5575 out: 5576 kfree(sa); 5577 return ret; 5578 } 5579 5580 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) 5581 { 5582 struct inode *inode = file_inode(file); 5583 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5584 size_t len; 5585 int ret; 5586 char label[BTRFS_LABEL_SIZE]; 5587 5588 spin_lock(&fs_info->super_lock); 5589 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE); 5590 spin_unlock(&fs_info->super_lock); 5591 5592 len = strnlen(label, BTRFS_LABEL_SIZE); 5593 5594 if (len == BTRFS_LABEL_SIZE) { 5595 btrfs_warn(fs_info, 5596 "label is too long, return the first %zu bytes", 5597 --len); 5598 } 5599 5600 ret = copy_to_user(arg, label, len); 5601 5602 return ret ? -EFAULT : 0; 5603 } 5604 5605 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) 5606 { 5607 struct inode *inode = file_inode(file); 5608 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5609 struct btrfs_root *root = BTRFS_I(inode)->root; 5610 struct btrfs_super_block *super_block = fs_info->super_copy; 5611 struct btrfs_trans_handle *trans; 5612 char label[BTRFS_LABEL_SIZE]; 5613 int ret; 5614 5615 if (!capable(CAP_SYS_ADMIN)) 5616 return -EPERM; 5617 5618 if (copy_from_user(label, arg, sizeof(label))) 5619 return -EFAULT; 5620 5621 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) { 5622 btrfs_err(fs_info, 5623 "unable to set label with more than %d bytes", 5624 BTRFS_LABEL_SIZE - 1); 5625 return -EINVAL; 5626 } 5627 5628 ret = mnt_want_write_file(file); 5629 if (ret) 5630 return ret; 5631 5632 trans = btrfs_start_transaction(root, 0); 5633 if (IS_ERR(trans)) { 5634 ret = PTR_ERR(trans); 5635 goto out_unlock; 5636 } 5637 5638 spin_lock(&fs_info->super_lock); 5639 strcpy(super_block->label, label); 5640 spin_unlock(&fs_info->super_lock); 5641 ret = btrfs_commit_transaction(trans); 5642 5643 out_unlock: 5644 mnt_drop_write_file(file); 5645 return ret; 5646 } 5647 5648 #define INIT_FEATURE_FLAGS(suffix) \ 5649 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \ 5650 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \ 5651 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix } 5652 5653 int btrfs_ioctl_get_supported_features(void __user *arg) 5654 { 5655 static const struct btrfs_ioctl_feature_flags features[3] = { 5656 INIT_FEATURE_FLAGS(SUPP), 5657 INIT_FEATURE_FLAGS(SAFE_SET), 5658 INIT_FEATURE_FLAGS(SAFE_CLEAR) 5659 }; 5660 5661 if (copy_to_user(arg, &features, sizeof(features))) 5662 return -EFAULT; 5663 5664 return 0; 5665 } 5666 5667 static int btrfs_ioctl_get_features(struct file *file, void __user *arg) 5668 { 5669 struct inode *inode = file_inode(file); 5670 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5671 struct btrfs_super_block *super_block = fs_info->super_copy; 5672 struct btrfs_ioctl_feature_flags features; 5673 5674 features.compat_flags = btrfs_super_compat_flags(super_block); 5675 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block); 5676 features.incompat_flags = btrfs_super_incompat_flags(super_block); 5677 5678 if (copy_to_user(arg, &features, sizeof(features))) 5679 return -EFAULT; 5680 5681 return 0; 5682 } 5683 5684 static int check_feature_bits(struct btrfs_fs_info *fs_info, 5685 enum btrfs_feature_set set, 5686 u64 change_mask, u64 flags, u64 supported_flags, 5687 u64 safe_set, u64 safe_clear) 5688 { 5689 const char *type = btrfs_feature_set_names[set]; 5690 char *names; 5691 u64 disallowed, unsupported; 5692 u64 set_mask = flags & change_mask; 5693 u64 clear_mask = ~flags & change_mask; 5694 5695 unsupported = set_mask & ~supported_flags; 5696 if (unsupported) { 5697 names = btrfs_printable_features(set, unsupported); 5698 if (names) { 5699 btrfs_warn(fs_info, 5700 "this kernel does not support the %s feature bit%s", 5701 names, strchr(names, ',') ? "s" : ""); 5702 kfree(names); 5703 } else 5704 btrfs_warn(fs_info, 5705 "this kernel does not support %s bits 0x%llx", 5706 type, unsupported); 5707 return -EOPNOTSUPP; 5708 } 5709 5710 disallowed = set_mask & ~safe_set; 5711 if (disallowed) { 5712 names = btrfs_printable_features(set, disallowed); 5713 if (names) { 5714 btrfs_warn(fs_info, 5715 "can't set the %s feature bit%s while mounted", 5716 names, strchr(names, ',') ? "s" : ""); 5717 kfree(names); 5718 } else 5719 btrfs_warn(fs_info, 5720 "can't set %s bits 0x%llx while mounted", 5721 type, disallowed); 5722 return -EPERM; 5723 } 5724 5725 disallowed = clear_mask & ~safe_clear; 5726 if (disallowed) { 5727 names = btrfs_printable_features(set, disallowed); 5728 if (names) { 5729 btrfs_warn(fs_info, 5730 "can't clear the %s feature bit%s while mounted", 5731 names, strchr(names, ',') ? "s" : ""); 5732 kfree(names); 5733 } else 5734 btrfs_warn(fs_info, 5735 "can't clear %s bits 0x%llx while mounted", 5736 type, disallowed); 5737 return -EPERM; 5738 } 5739 5740 return 0; 5741 } 5742 5743 #define check_feature(fs_info, change_mask, flags, mask_base) \ 5744 check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \ 5745 BTRFS_FEATURE_ ## mask_base ## _SUPP, \ 5746 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \ 5747 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR) 5748 5749 static int btrfs_ioctl_set_features(struct file *file, void __user *arg) 5750 { 5751 struct inode *inode = file_inode(file); 5752 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5753 struct btrfs_root *root = BTRFS_I(inode)->root; 5754 struct btrfs_super_block *super_block = fs_info->super_copy; 5755 struct btrfs_ioctl_feature_flags flags[2]; 5756 struct btrfs_trans_handle *trans; 5757 u64 newflags; 5758 int ret; 5759 5760 if (!capable(CAP_SYS_ADMIN)) 5761 return -EPERM; 5762 5763 if (copy_from_user(flags, arg, sizeof(flags))) 5764 return -EFAULT; 5765 5766 /* Nothing to do */ 5767 if (!flags[0].compat_flags && !flags[0].compat_ro_flags && 5768 !flags[0].incompat_flags) 5769 return 0; 5770 5771 ret = check_feature(fs_info, flags[0].compat_flags, 5772 flags[1].compat_flags, COMPAT); 5773 if (ret) 5774 return ret; 5775 5776 ret = check_feature(fs_info, flags[0].compat_ro_flags, 5777 flags[1].compat_ro_flags, COMPAT_RO); 5778 if (ret) 5779 return ret; 5780 5781 ret = check_feature(fs_info, flags[0].incompat_flags, 5782 flags[1].incompat_flags, INCOMPAT); 5783 if (ret) 5784 return ret; 5785 5786 ret = mnt_want_write_file(file); 5787 if (ret) 5788 return ret; 5789 5790 trans = btrfs_start_transaction(root, 0); 5791 if (IS_ERR(trans)) { 5792 ret = PTR_ERR(trans); 5793 goto out_drop_write; 5794 } 5795 5796 spin_lock(&fs_info->super_lock); 5797 newflags = btrfs_super_compat_flags(super_block); 5798 newflags |= flags[0].compat_flags & flags[1].compat_flags; 5799 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags); 5800 btrfs_set_super_compat_flags(super_block, newflags); 5801 5802 newflags = btrfs_super_compat_ro_flags(super_block); 5803 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags; 5804 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags); 5805 btrfs_set_super_compat_ro_flags(super_block, newflags); 5806 5807 newflags = btrfs_super_incompat_flags(super_block); 5808 newflags |= flags[0].incompat_flags & flags[1].incompat_flags; 5809 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags); 5810 btrfs_set_super_incompat_flags(super_block, newflags); 5811 spin_unlock(&fs_info->super_lock); 5812 5813 ret = btrfs_commit_transaction(trans); 5814 out_drop_write: 5815 mnt_drop_write_file(file); 5816 5817 return ret; 5818 } 5819 5820 static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat) 5821 { 5822 struct btrfs_ioctl_send_args *arg; 5823 int ret; 5824 5825 if (compat) { 5826 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) 5827 struct btrfs_ioctl_send_args_32 args32; 5828 5829 ret = copy_from_user(&args32, argp, sizeof(args32)); 5830 if (ret) 5831 return -EFAULT; 5832 arg = kzalloc(sizeof(*arg), GFP_KERNEL); 5833 if (!arg) 5834 return -ENOMEM; 5835 arg->send_fd = args32.send_fd; 5836 arg->clone_sources_count = args32.clone_sources_count; 5837 arg->clone_sources = compat_ptr(args32.clone_sources); 5838 arg->parent_root = args32.parent_root; 5839 arg->flags = args32.flags; 5840 memcpy(arg->reserved, args32.reserved, 5841 sizeof(args32.reserved)); 5842 #else 5843 return -ENOTTY; 5844 #endif 5845 } else { 5846 arg = memdup_user(argp, sizeof(*arg)); 5847 if (IS_ERR(arg)) 5848 return PTR_ERR(arg); 5849 } 5850 ret = btrfs_ioctl_send(file, arg); 5851 kfree(arg); 5852 return ret; 5853 } 5854 5855 long btrfs_ioctl(struct file *file, unsigned int 5856 cmd, unsigned long arg) 5857 { 5858 struct inode *inode = file_inode(file); 5859 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5860 struct btrfs_root *root = BTRFS_I(inode)->root; 5861 void __user *argp = (void __user *)arg; 5862 5863 switch (cmd) { 5864 case FS_IOC_GETFLAGS: 5865 return btrfs_ioctl_getflags(file, argp); 5866 case FS_IOC_SETFLAGS: 5867 return btrfs_ioctl_setflags(file, argp); 5868 case FS_IOC_GETVERSION: 5869 return btrfs_ioctl_getversion(file, argp); 5870 case FITRIM: 5871 return btrfs_ioctl_fitrim(file, argp); 5872 case BTRFS_IOC_SNAP_CREATE: 5873 return btrfs_ioctl_snap_create(file, argp, 0); 5874 case BTRFS_IOC_SNAP_CREATE_V2: 5875 return btrfs_ioctl_snap_create_v2(file, argp, 0); 5876 case BTRFS_IOC_SUBVOL_CREATE: 5877 return btrfs_ioctl_snap_create(file, argp, 1); 5878 case BTRFS_IOC_SUBVOL_CREATE_V2: 5879 return btrfs_ioctl_snap_create_v2(file, argp, 1); 5880 case BTRFS_IOC_SNAP_DESTROY: 5881 return btrfs_ioctl_snap_destroy(file, argp); 5882 case BTRFS_IOC_SUBVOL_GETFLAGS: 5883 return btrfs_ioctl_subvol_getflags(file, argp); 5884 case BTRFS_IOC_SUBVOL_SETFLAGS: 5885 return btrfs_ioctl_subvol_setflags(file, argp); 5886 case BTRFS_IOC_DEFAULT_SUBVOL: 5887 return btrfs_ioctl_default_subvol(file, argp); 5888 case BTRFS_IOC_DEFRAG: 5889 return btrfs_ioctl_defrag(file, NULL); 5890 case BTRFS_IOC_DEFRAG_RANGE: 5891 return btrfs_ioctl_defrag(file, argp); 5892 case BTRFS_IOC_RESIZE: 5893 return btrfs_ioctl_resize(file, argp); 5894 case BTRFS_IOC_ADD_DEV: 5895 return btrfs_ioctl_add_dev(fs_info, argp); 5896 case BTRFS_IOC_RM_DEV: 5897 return btrfs_ioctl_rm_dev(file, argp); 5898 case BTRFS_IOC_RM_DEV_V2: 5899 return btrfs_ioctl_rm_dev_v2(file, argp); 5900 case BTRFS_IOC_FS_INFO: 5901 return btrfs_ioctl_fs_info(fs_info, argp); 5902 case BTRFS_IOC_DEV_INFO: 5903 return btrfs_ioctl_dev_info(fs_info, argp); 5904 case BTRFS_IOC_BALANCE: 5905 return btrfs_ioctl_balance(file, NULL); 5906 case BTRFS_IOC_TREE_SEARCH: 5907 return btrfs_ioctl_tree_search(file, argp); 5908 case BTRFS_IOC_TREE_SEARCH_V2: 5909 return btrfs_ioctl_tree_search_v2(file, argp); 5910 case BTRFS_IOC_INO_LOOKUP: 5911 return btrfs_ioctl_ino_lookup(file, argp); 5912 case BTRFS_IOC_INO_PATHS: 5913 return btrfs_ioctl_ino_to_path(root, argp); 5914 case BTRFS_IOC_LOGICAL_INO: 5915 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1); 5916 case BTRFS_IOC_LOGICAL_INO_V2: 5917 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2); 5918 case BTRFS_IOC_SPACE_INFO: 5919 return btrfs_ioctl_space_info(fs_info, argp); 5920 case BTRFS_IOC_SYNC: { 5921 int ret; 5922 5923 ret = btrfs_start_delalloc_roots(fs_info, -1); 5924 if (ret) 5925 return ret; 5926 ret = btrfs_sync_fs(inode->i_sb, 1); 5927 /* 5928 * The transaction thread may want to do more work, 5929 * namely it pokes the cleaner kthread that will start 5930 * processing uncleaned subvols. 5931 */ 5932 wake_up_process(fs_info->transaction_kthread); 5933 return ret; 5934 } 5935 case BTRFS_IOC_START_SYNC: 5936 return btrfs_ioctl_start_sync(root, argp); 5937 case BTRFS_IOC_WAIT_SYNC: 5938 return btrfs_ioctl_wait_sync(fs_info, argp); 5939 case BTRFS_IOC_SCRUB: 5940 return btrfs_ioctl_scrub(file, argp); 5941 case BTRFS_IOC_SCRUB_CANCEL: 5942 return btrfs_ioctl_scrub_cancel(fs_info); 5943 case BTRFS_IOC_SCRUB_PROGRESS: 5944 return btrfs_ioctl_scrub_progress(fs_info, argp); 5945 case BTRFS_IOC_BALANCE_V2: 5946 return btrfs_ioctl_balance(file, argp); 5947 case BTRFS_IOC_BALANCE_CTL: 5948 return btrfs_ioctl_balance_ctl(fs_info, arg); 5949 case BTRFS_IOC_BALANCE_PROGRESS: 5950 return btrfs_ioctl_balance_progress(fs_info, argp); 5951 case BTRFS_IOC_SET_RECEIVED_SUBVOL: 5952 return btrfs_ioctl_set_received_subvol(file, argp); 5953 #ifdef CONFIG_64BIT 5954 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32: 5955 return btrfs_ioctl_set_received_subvol_32(file, argp); 5956 #endif 5957 case BTRFS_IOC_SEND: 5958 return _btrfs_ioctl_send(file, argp, false); 5959 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) 5960 case BTRFS_IOC_SEND_32: 5961 return _btrfs_ioctl_send(file, argp, true); 5962 #endif 5963 case BTRFS_IOC_GET_DEV_STATS: 5964 return btrfs_ioctl_get_dev_stats(fs_info, argp); 5965 case BTRFS_IOC_QUOTA_CTL: 5966 return btrfs_ioctl_quota_ctl(file, argp); 5967 case BTRFS_IOC_QGROUP_ASSIGN: 5968 return btrfs_ioctl_qgroup_assign(file, argp); 5969 case BTRFS_IOC_QGROUP_CREATE: 5970 return btrfs_ioctl_qgroup_create(file, argp); 5971 case BTRFS_IOC_QGROUP_LIMIT: 5972 return btrfs_ioctl_qgroup_limit(file, argp); 5973 case BTRFS_IOC_QUOTA_RESCAN: 5974 return btrfs_ioctl_quota_rescan(file, argp); 5975 case BTRFS_IOC_QUOTA_RESCAN_STATUS: 5976 return btrfs_ioctl_quota_rescan_status(file, argp); 5977 case BTRFS_IOC_QUOTA_RESCAN_WAIT: 5978 return btrfs_ioctl_quota_rescan_wait(file, argp); 5979 case BTRFS_IOC_DEV_REPLACE: 5980 return btrfs_ioctl_dev_replace(fs_info, argp); 5981 case BTRFS_IOC_GET_FSLABEL: 5982 return btrfs_ioctl_get_fslabel(file, argp); 5983 case BTRFS_IOC_SET_FSLABEL: 5984 return btrfs_ioctl_set_fslabel(file, argp); 5985 case BTRFS_IOC_GET_SUPPORTED_FEATURES: 5986 return btrfs_ioctl_get_supported_features(argp); 5987 case BTRFS_IOC_GET_FEATURES: 5988 return btrfs_ioctl_get_features(file, argp); 5989 case BTRFS_IOC_SET_FEATURES: 5990 return btrfs_ioctl_set_features(file, argp); 5991 case FS_IOC_FSGETXATTR: 5992 return btrfs_ioctl_fsgetxattr(file, argp); 5993 case FS_IOC_FSSETXATTR: 5994 return btrfs_ioctl_fssetxattr(file, argp); 5995 case BTRFS_IOC_GET_SUBVOL_INFO: 5996 return btrfs_ioctl_get_subvol_info(file, argp); 5997 case BTRFS_IOC_GET_SUBVOL_ROOTREF: 5998 return btrfs_ioctl_get_subvol_rootref(file, argp); 5999 case BTRFS_IOC_INO_LOOKUP_USER: 6000 return btrfs_ioctl_ino_lookup_user(file, argp); 6001 } 6002 6003 return -ENOTTY; 6004 } 6005 6006 #ifdef CONFIG_COMPAT 6007 long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 6008 { 6009 /* 6010 * These all access 32-bit values anyway so no further 6011 * handling is necessary. 6012 */ 6013 switch (cmd) { 6014 case FS_IOC32_GETFLAGS: 6015 cmd = FS_IOC_GETFLAGS; 6016 break; 6017 case FS_IOC32_SETFLAGS: 6018 cmd = FS_IOC_SETFLAGS; 6019 break; 6020 case FS_IOC32_GETVERSION: 6021 cmd = FS_IOC_GETVERSION; 6022 break; 6023 } 6024 6025 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); 6026 } 6027 #endif 6028