1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2007 Oracle. All rights reserved. 4 */ 5 6 #ifndef BTRFS_CTREE_H 7 #define BTRFS_CTREE_H 8 9 #include "linux/cleanup.h" 10 #include <linux/pagemap.h> 11 #include <linux/spinlock.h> 12 #include <linux/rbtree.h> 13 #include <linux/mutex.h> 14 #include <linux/wait.h> 15 #include <linux/list.h> 16 #include <linux/atomic.h> 17 #include <linux/xarray.h> 18 #include <linux/refcount.h> 19 #include <uapi/linux/btrfs_tree.h> 20 #include "locking.h" 21 #include "fs.h" 22 #include "accessors.h" 23 #include "extent-io-tree.h" 24 25 struct extent_buffer; 26 struct btrfs_block_rsv; 27 struct btrfs_trans_handle; 28 struct btrfs_block_group; 29 30 /* Read ahead values for struct btrfs_path.reada */ 31 enum { 32 READA_NONE, 33 READA_BACK, 34 READA_FORWARD, 35 /* 36 * Similar to READA_FORWARD but unlike it: 37 * 38 * 1) It will trigger readahead even for leaves that are not close to 39 * each other on disk; 40 * 2) It also triggers readahead for nodes; 41 * 3) During a search, even when a node or leaf is already in memory, it 42 * will still trigger readahead for other nodes and leaves that follow 43 * it. 44 * 45 * This is meant to be used only when we know we are iterating over the 46 * entire tree or a very large part of it. 47 */ 48 READA_FORWARD_ALWAYS, 49 }; 50 51 /* 52 * btrfs_paths remember the path taken from the root down to the leaf. 53 * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point 54 * to any other levels that are present. 55 * 56 * The slots array records the index of the item or block pointer 57 * used while walking the tree. 58 */ 59 struct btrfs_path { 60 struct extent_buffer *nodes[BTRFS_MAX_LEVEL]; 61 int slots[BTRFS_MAX_LEVEL]; 62 /* if there is real range locking, this locks field will change */ 63 u8 locks[BTRFS_MAX_LEVEL]; 64 u8 reada; 65 /* keep some upper locks as we walk down */ 66 u8 lowest_level; 67 68 /* 69 * set by btrfs_split_item, tells search_slot to keep all locks 70 * and to force calls to keep space in the nodes 71 */ 72 unsigned int search_for_split:1; 73 unsigned int keep_locks:1; 74 unsigned int skip_locking:1; 75 unsigned int search_commit_root:1; 76 unsigned int need_commit_sem:1; 77 unsigned int skip_release_on_error:1; 78 /* 79 * Indicate that new item (btrfs_search_slot) is extending already 80 * existing item and ins_len contains only the data size and not item 81 * header (ie. sizeof(struct btrfs_item) is not included). 82 */ 83 unsigned int search_for_extension:1; 84 /* Stop search if any locks need to be taken (for read) */ 85 unsigned int nowait:1; 86 }; 87 88 #define BTRFS_PATH_AUTO_FREE(path_name) \ 89 struct btrfs_path *path_name __free(btrfs_free_path) = NULL 90 91 /* 92 * The state of btrfs root 93 */ 94 enum { 95 /* 96 * btrfs_record_root_in_trans is a multi-step process, and it can race 97 * with the balancing code. But the race is very small, and only the 98 * first time the root is added to each transaction. So IN_TRANS_SETUP 99 * is used to tell us when more checks are required 100 */ 101 BTRFS_ROOT_IN_TRANS_SETUP, 102 103 /* 104 * Set if tree blocks of this root can be shared by other roots. 105 * Only subvolume trees and their reloc trees have this bit set. 106 * Conflicts with TRACK_DIRTY bit. 107 * 108 * This affects two things: 109 * 110 * - How balance works 111 * For shareable roots, we need to use reloc tree and do path 112 * replacement for balance, and need various pre/post hooks for 113 * snapshot creation to handle them. 114 * 115 * While for non-shareable trees, we just simply do a tree search 116 * with COW. 117 * 118 * - How dirty roots are tracked 119 * For shareable roots, btrfs_record_root_in_trans() is needed to 120 * track them, while non-subvolume roots have TRACK_DIRTY bit, they 121 * don't need to set this manually. 122 */ 123 BTRFS_ROOT_SHAREABLE, 124 BTRFS_ROOT_TRACK_DIRTY, 125 BTRFS_ROOT_IN_RADIX, 126 BTRFS_ROOT_ORPHAN_ITEM_INSERTED, 127 BTRFS_ROOT_DEFRAG_RUNNING, 128 BTRFS_ROOT_FORCE_COW, 129 BTRFS_ROOT_MULTI_LOG_TASKS, 130 BTRFS_ROOT_DIRTY, 131 BTRFS_ROOT_DELETING, 132 133 /* 134 * Reloc tree is orphan, only kept here for qgroup delayed subtree scan 135 * 136 * Set for the subvolume tree owning the reloc tree. 137 */ 138 BTRFS_ROOT_DEAD_RELOC_TREE, 139 /* Mark dead root stored on device whose cleanup needs to be resumed */ 140 BTRFS_ROOT_DEAD_TREE, 141 /* The root has a log tree. Used for subvolume roots and the tree root. */ 142 BTRFS_ROOT_HAS_LOG_TREE, 143 /* Qgroup flushing is in progress */ 144 BTRFS_ROOT_QGROUP_FLUSHING, 145 /* We started the orphan cleanup for this root. */ 146 BTRFS_ROOT_ORPHAN_CLEANUP, 147 /* This root has a drop operation that was started previously. */ 148 BTRFS_ROOT_UNFINISHED_DROP, 149 /* This reloc root needs to have its buffers lockdep class reset. */ 150 BTRFS_ROOT_RESET_LOCKDEP_CLASS, 151 }; 152 153 /* 154 * Record swapped tree blocks of a subvolume tree for delayed subtree trace 155 * code. For detail check comment in fs/btrfs/qgroup.c. 156 */ 157 struct btrfs_qgroup_swapped_blocks { 158 spinlock_t lock; 159 /* RM_EMPTY_ROOT() of above blocks[] */ 160 bool swapped; 161 struct rb_root blocks[BTRFS_MAX_LEVEL]; 162 }; 163 164 /* 165 * in ram representation of the tree. extent_root is used for all allocations 166 * and for the extent tree extent_root root. 167 */ 168 struct btrfs_root { 169 struct rb_node rb_node; 170 171 struct extent_buffer *node; 172 173 struct extent_buffer *commit_root; 174 struct btrfs_root *log_root; 175 struct btrfs_root *reloc_root; 176 177 unsigned long state; 178 struct btrfs_root_item root_item; 179 struct btrfs_key root_key; 180 struct btrfs_fs_info *fs_info; 181 struct extent_io_tree dirty_log_pages; 182 183 struct mutex objectid_mutex; 184 185 spinlock_t accounting_lock; 186 struct btrfs_block_rsv *block_rsv; 187 188 struct mutex log_mutex; 189 wait_queue_head_t log_writer_wait; 190 wait_queue_head_t log_commit_wait[2]; 191 struct list_head log_ctxs[2]; 192 /* Used only for log trees of subvolumes, not for the log root tree */ 193 atomic_t log_writers; 194 atomic_t log_commit[2]; 195 /* Used only for log trees of subvolumes, not for the log root tree */ 196 atomic_t log_batch; 197 /* 198 * Protected by the 'log_mutex' lock but can be read without holding 199 * that lock to avoid unnecessary lock contention, in which case it 200 * should be read using btrfs_get_root_log_transid() except if it's a 201 * log tree in which case it can be directly accessed. Updates to this 202 * field should always use btrfs_set_root_log_transid(), except for log 203 * trees where the field can be updated directly. 204 */ 205 int log_transid; 206 /* No matter the commit succeeds or not*/ 207 int log_transid_committed; 208 /* 209 * Just be updated when the commit succeeds. Use 210 * btrfs_get_root_last_log_commit() and btrfs_set_root_last_log_commit() 211 * to access this field. 212 */ 213 int last_log_commit; 214 pid_t log_start_pid; 215 216 u64 last_trans; 217 218 u64 free_objectid; 219 220 struct btrfs_key defrag_progress; 221 struct btrfs_key defrag_max; 222 223 /* The dirty list is only used by non-shareable roots */ 224 struct list_head dirty_list; 225 226 struct list_head root_list; 227 228 /* 229 * Xarray that keeps track of in-memory inodes, protected by the lock 230 * @inode_lock. 231 */ 232 struct xarray inodes; 233 234 /* 235 * Xarray that keeps track of delayed nodes of every inode, protected 236 * by @inode_lock. 237 */ 238 struct xarray delayed_nodes; 239 /* 240 * right now this just gets used so that a root has its own devid 241 * for stat. It may be used for more later 242 */ 243 dev_t anon_dev; 244 245 spinlock_t root_item_lock; 246 refcount_t refs; 247 248 struct mutex delalloc_mutex; 249 spinlock_t delalloc_lock; 250 /* 251 * all of the inodes that have delalloc bytes. It is possible for 252 * this list to be empty even when there is still dirty data=ordered 253 * extents waiting to finish IO. 254 */ 255 struct list_head delalloc_inodes; 256 struct list_head delalloc_root; 257 u64 nr_delalloc_inodes; 258 259 struct mutex ordered_extent_mutex; 260 /* 261 * this is used by the balancing code to wait for all the pending 262 * ordered extents 263 */ 264 spinlock_t ordered_extent_lock; 265 266 /* 267 * all of the data=ordered extents pending writeback 268 * these can span multiple transactions and basically include 269 * every dirty data page that isn't from nodatacow 270 */ 271 struct list_head ordered_extents; 272 struct list_head ordered_root; 273 u64 nr_ordered_extents; 274 275 /* 276 * Not empty if this subvolume root has gone through tree block swap 277 * (relocation) 278 * 279 * Will be used by reloc_control::dirty_subvol_roots. 280 */ 281 struct list_head reloc_dirty_list; 282 283 /* 284 * Number of currently running SEND ioctls to prevent 285 * manipulation with the read-only status via SUBVOL_SETFLAGS 286 */ 287 int send_in_progress; 288 /* 289 * Number of currently running deduplication operations that have a 290 * destination inode belonging to this root. Protected by the lock 291 * root_item_lock. 292 */ 293 int dedupe_in_progress; 294 /* For exclusion of snapshot creation and nocow writes */ 295 struct btrfs_drew_lock snapshot_lock; 296 297 atomic_t snapshot_force_cow; 298 299 /* For qgroup metadata reserved space */ 300 spinlock_t qgroup_meta_rsv_lock; 301 u64 qgroup_meta_rsv_pertrans; 302 u64 qgroup_meta_rsv_prealloc; 303 wait_queue_head_t qgroup_flush_wait; 304 305 /* Number of active swapfiles */ 306 atomic_t nr_swapfiles; 307 308 /* Record pairs of swapped blocks for qgroup */ 309 struct btrfs_qgroup_swapped_blocks swapped_blocks; 310 311 /* Used only by log trees, when logging csum items */ 312 struct extent_io_tree log_csum_range; 313 314 /* Used in simple quotas, track root during relocation. */ 315 u64 relocation_src_root; 316 317 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 318 u64 alloc_bytenr; 319 #endif 320 321 #ifdef CONFIG_BTRFS_DEBUG 322 struct list_head leak_list; 323 #endif 324 }; 325 326 static inline bool btrfs_root_readonly(const struct btrfs_root *root) 327 { 328 /* Byte-swap the constant at compile time, root_item::flags is LE */ 329 return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_RDONLY)) != 0; 330 } 331 332 static inline bool btrfs_root_dead(const struct btrfs_root *root) 333 { 334 /* Byte-swap the constant at compile time, root_item::flags is LE */ 335 return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_DEAD)) != 0; 336 } 337 338 static inline u64 btrfs_root_id(const struct btrfs_root *root) 339 { 340 return root->root_key.objectid; 341 } 342 343 static inline int btrfs_get_root_log_transid(const struct btrfs_root *root) 344 { 345 return READ_ONCE(root->log_transid); 346 } 347 348 static inline void btrfs_set_root_log_transid(struct btrfs_root *root, int log_transid) 349 { 350 WRITE_ONCE(root->log_transid, log_transid); 351 } 352 353 static inline int btrfs_get_root_last_log_commit(const struct btrfs_root *root) 354 { 355 return READ_ONCE(root->last_log_commit); 356 } 357 358 static inline void btrfs_set_root_last_log_commit(struct btrfs_root *root, int commit_id) 359 { 360 WRITE_ONCE(root->last_log_commit, commit_id); 361 } 362 363 static inline u64 btrfs_get_root_last_trans(const struct btrfs_root *root) 364 { 365 return READ_ONCE(root->last_trans); 366 } 367 368 static inline void btrfs_set_root_last_trans(struct btrfs_root *root, u64 transid) 369 { 370 WRITE_ONCE(root->last_trans, transid); 371 } 372 373 /* 374 * Structure that conveys information about an extent that is going to replace 375 * all the extents in a file range. 376 */ 377 struct btrfs_replace_extent_info { 378 u64 disk_offset; 379 u64 disk_len; 380 u64 data_offset; 381 u64 data_len; 382 u64 file_offset; 383 /* Pointer to a file extent item of type regular or prealloc. */ 384 char *extent_buf; 385 /* 386 * Set to true when attempting to replace a file range with a new extent 387 * described by this structure, set to false when attempting to clone an 388 * existing extent into a file range. 389 */ 390 bool is_new_extent; 391 /* Indicate if we should update the inode's mtime and ctime. */ 392 bool update_times; 393 /* Meaningful only if is_new_extent is true. */ 394 int qgroup_reserved; 395 /* 396 * Meaningful only if is_new_extent is true. 397 * Used to track how many extent items we have already inserted in a 398 * subvolume tree that refer to the extent described by this structure, 399 * so that we know when to create a new delayed ref or update an existing 400 * one. 401 */ 402 int insertions; 403 }; 404 405 /* Arguments for btrfs_drop_extents() */ 406 struct btrfs_drop_extents_args { 407 /* Input parameters */ 408 409 /* 410 * If NULL, btrfs_drop_extents() will allocate and free its own path. 411 * If 'replace_extent' is true, this must not be NULL. Also the path 412 * is always released except if 'replace_extent' is true and 413 * btrfs_drop_extents() sets 'extent_inserted' to true, in which case 414 * the path is kept locked. 415 */ 416 struct btrfs_path *path; 417 /* Start offset of the range to drop extents from */ 418 u64 start; 419 /* End (exclusive, last byte + 1) of the range to drop extents from */ 420 u64 end; 421 /* If true drop all the extent maps in the range */ 422 bool drop_cache; 423 /* 424 * If true it means we want to insert a new extent after dropping all 425 * the extents in the range. If this is true, the 'extent_item_size' 426 * parameter must be set as well and the 'extent_inserted' field will 427 * be set to true by btrfs_drop_extents() if it could insert the new 428 * extent. 429 * Note: when this is set to true the path must not be NULL. 430 */ 431 bool replace_extent; 432 /* 433 * Used if 'replace_extent' is true. Size of the file extent item to 434 * insert after dropping all existing extents in the range 435 */ 436 u32 extent_item_size; 437 438 /* Output parameters */ 439 440 /* 441 * Set to the minimum between the input parameter 'end' and the end 442 * (exclusive, last byte + 1) of the last dropped extent. This is always 443 * set even if btrfs_drop_extents() returns an error. 444 */ 445 u64 drop_end; 446 /* 447 * The number of allocated bytes found in the range. This can be smaller 448 * than the range's length when there are holes in the range. 449 */ 450 u64 bytes_found; 451 /* 452 * Only set if 'replace_extent' is true. Set to true if we were able 453 * to insert a replacement extent after dropping all extents in the 454 * range, otherwise set to false by btrfs_drop_extents(). 455 * Also, if btrfs_drop_extents() has set this to true it means it 456 * returned with the path locked, otherwise if it has set this to 457 * false it has returned with the path released. 458 */ 459 bool extent_inserted; 460 }; 461 462 struct btrfs_file_private { 463 void *filldir_buf; 464 u64 last_index; 465 struct extent_state *llseek_cached_state; 466 /* Task that allocated this structure. */ 467 struct task_struct *owner_task; 468 }; 469 470 static inline u32 BTRFS_LEAF_DATA_SIZE(const struct btrfs_fs_info *info) 471 { 472 return info->nodesize - sizeof(struct btrfs_header); 473 } 474 475 static inline u32 BTRFS_MAX_ITEM_SIZE(const struct btrfs_fs_info *info) 476 { 477 return BTRFS_LEAF_DATA_SIZE(info) - sizeof(struct btrfs_item); 478 } 479 480 static inline u32 BTRFS_NODEPTRS_PER_BLOCK(const struct btrfs_fs_info *info) 481 { 482 return BTRFS_LEAF_DATA_SIZE(info) / sizeof(struct btrfs_key_ptr); 483 } 484 485 static inline u32 BTRFS_MAX_XATTR_SIZE(const struct btrfs_fs_info *info) 486 { 487 return BTRFS_MAX_ITEM_SIZE(info) - sizeof(struct btrfs_dir_item); 488 } 489 490 #define BTRFS_BYTES_TO_BLKS(fs_info, bytes) \ 491 ((bytes) >> (fs_info)->sectorsize_bits) 492 493 static inline gfp_t btrfs_alloc_write_mask(struct address_space *mapping) 494 { 495 return mapping_gfp_constraint(mapping, ~__GFP_FS); 496 } 497 498 void btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info, u64 start, u64 end); 499 int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr, 500 u64 num_bytes, u64 *actual_bytes); 501 int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range); 502 503 /* ctree.c */ 504 int __init btrfs_ctree_init(void); 505 void __cold btrfs_ctree_exit(void); 506 507 int btrfs_bin_search(struct extent_buffer *eb, int first_slot, 508 const struct btrfs_key *key, int *slot); 509 510 int __pure btrfs_comp_cpu_keys(const struct btrfs_key *k1, const struct btrfs_key *k2); 511 512 #ifdef __LITTLE_ENDIAN 513 514 /* 515 * Compare two keys, on little-endian the disk order is same as CPU order and 516 * we can avoid the conversion. 517 */ 518 static inline int btrfs_comp_keys(const struct btrfs_disk_key *disk_key, 519 const struct btrfs_key *k2) 520 { 521 const struct btrfs_key *k1 = (const struct btrfs_key *)disk_key; 522 523 return btrfs_comp_cpu_keys(k1, k2); 524 } 525 526 #else 527 528 /* Compare two keys in a memcmp fashion. */ 529 static inline int btrfs_comp_keys(const struct btrfs_disk_key *disk, 530 const struct btrfs_key *k2) 531 { 532 struct btrfs_key k1; 533 534 btrfs_disk_key_to_cpu(&k1, disk); 535 536 return btrfs_comp_cpu_keys(&k1, k2); 537 } 538 539 #endif 540 541 int btrfs_previous_item(struct btrfs_root *root, 542 struct btrfs_path *path, u64 min_objectid, 543 int type); 544 int btrfs_previous_extent_item(struct btrfs_root *root, 545 struct btrfs_path *path, u64 min_objectid); 546 void btrfs_set_item_key_safe(struct btrfs_trans_handle *trans, 547 const struct btrfs_path *path, 548 const struct btrfs_key *new_key); 549 struct extent_buffer *btrfs_root_node(struct btrfs_root *root); 550 int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path, 551 struct btrfs_key *key, int lowest_level, 552 u64 min_trans); 553 int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, 554 struct btrfs_path *path, 555 u64 min_trans); 556 struct extent_buffer *btrfs_read_node_slot(struct extent_buffer *parent, 557 int slot); 558 559 int btrfs_cow_block(struct btrfs_trans_handle *trans, 560 struct btrfs_root *root, struct extent_buffer *buf, 561 struct extent_buffer *parent, int parent_slot, 562 struct extent_buffer **cow_ret, 563 enum btrfs_lock_nesting nest); 564 int btrfs_force_cow_block(struct btrfs_trans_handle *trans, 565 struct btrfs_root *root, 566 struct extent_buffer *buf, 567 struct extent_buffer *parent, int parent_slot, 568 struct extent_buffer **cow_ret, 569 u64 search_start, u64 empty_size, 570 enum btrfs_lock_nesting nest); 571 int btrfs_copy_root(struct btrfs_trans_handle *trans, 572 struct btrfs_root *root, 573 struct extent_buffer *buf, 574 struct extent_buffer **cow_ret, u64 new_root_objectid); 575 bool btrfs_block_can_be_shared(struct btrfs_trans_handle *trans, 576 struct btrfs_root *root, 577 struct extent_buffer *buf); 578 int btrfs_del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, 579 struct btrfs_path *path, int level, int slot); 580 void btrfs_extend_item(struct btrfs_trans_handle *trans, 581 const struct btrfs_path *path, u32 data_size); 582 void btrfs_truncate_item(struct btrfs_trans_handle *trans, 583 const struct btrfs_path *path, u32 new_size, int from_end); 584 int btrfs_split_item(struct btrfs_trans_handle *trans, 585 struct btrfs_root *root, 586 struct btrfs_path *path, 587 const struct btrfs_key *new_key, 588 unsigned long split_offset); 589 int btrfs_duplicate_item(struct btrfs_trans_handle *trans, 590 struct btrfs_root *root, 591 struct btrfs_path *path, 592 const struct btrfs_key *new_key); 593 int btrfs_find_item(struct btrfs_root *fs_root, struct btrfs_path *path, 594 u64 inum, u64 ioff, u8 key_type, struct btrfs_key *found_key); 595 int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root, 596 const struct btrfs_key *key, struct btrfs_path *p, 597 int ins_len, int cow); 598 int btrfs_search_old_slot(struct btrfs_root *root, const struct btrfs_key *key, 599 struct btrfs_path *p, u64 time_seq); 600 int btrfs_search_slot_for_read(struct btrfs_root *root, 601 const struct btrfs_key *key, 602 struct btrfs_path *p, int find_higher, 603 int return_any); 604 void btrfs_release_path(struct btrfs_path *p); 605 struct btrfs_path *btrfs_alloc_path(void); 606 void btrfs_free_path(struct btrfs_path *p); 607 DEFINE_FREE(btrfs_free_path, struct btrfs_path *, btrfs_free_path(_T)) 608 609 int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, 610 struct btrfs_path *path, int slot, int nr); 611 static inline int btrfs_del_item(struct btrfs_trans_handle *trans, 612 struct btrfs_root *root, 613 struct btrfs_path *path) 614 { 615 return btrfs_del_items(trans, root, path, path->slots[0], 1); 616 } 617 618 /* 619 * Describes a batch of items to insert in a btree. This is used by 620 * btrfs_insert_empty_items(). 621 */ 622 struct btrfs_item_batch { 623 /* 624 * Pointer to an array containing the keys of the items to insert (in 625 * sorted order). 626 */ 627 const struct btrfs_key *keys; 628 /* Pointer to an array containing the data size for each item to insert. */ 629 const u32 *data_sizes; 630 /* 631 * The sum of data sizes for all items. The caller can compute this while 632 * setting up the data_sizes array, so it ends up being more efficient 633 * than having btrfs_insert_empty_items() or setup_item_for_insert() 634 * doing it, as it would avoid an extra loop over a potentially large 635 * array, and in the case of setup_item_for_insert(), we would be doing 636 * it while holding a write lock on a leaf and often on upper level nodes 637 * too, unnecessarily increasing the size of a critical section. 638 */ 639 u32 total_data_size; 640 /* Size of the keys and data_sizes arrays (number of items in the batch). */ 641 int nr; 642 }; 643 644 void btrfs_setup_item_for_insert(struct btrfs_trans_handle *trans, 645 struct btrfs_root *root, 646 struct btrfs_path *path, 647 const struct btrfs_key *key, 648 u32 data_size); 649 int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, 650 const struct btrfs_key *key, void *data, u32 data_size); 651 int btrfs_insert_empty_items(struct btrfs_trans_handle *trans, 652 struct btrfs_root *root, 653 struct btrfs_path *path, 654 const struct btrfs_item_batch *batch); 655 656 static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, 657 struct btrfs_root *root, 658 struct btrfs_path *path, 659 const struct btrfs_key *key, 660 u32 data_size) 661 { 662 struct btrfs_item_batch batch; 663 664 batch.keys = key; 665 batch.data_sizes = &data_size; 666 batch.total_data_size = data_size; 667 batch.nr = 1; 668 669 return btrfs_insert_empty_items(trans, root, path, &batch); 670 } 671 672 int btrfs_next_old_leaf(struct btrfs_root *root, struct btrfs_path *path, 673 u64 time_seq); 674 675 int btrfs_search_backwards(struct btrfs_root *root, struct btrfs_key *key, 676 struct btrfs_path *path); 677 678 int btrfs_get_next_valid_item(struct btrfs_root *root, struct btrfs_key *key, 679 struct btrfs_path *path); 680 681 /* 682 * Search in @root for a given @key, and store the slot found in @found_key. 683 * 684 * @root: The root node of the tree. 685 * @key: The key we are looking for. 686 * @found_key: Will hold the found item. 687 * @path: Holds the current slot/leaf. 688 * @iter_ret: Contains the value returned from btrfs_search_slot or 689 * btrfs_get_next_valid_item, whichever was executed last. 690 * 691 * The @iter_ret is an output variable that will contain the return value of 692 * btrfs_search_slot, if it encountered an error, or the value returned from 693 * btrfs_get_next_valid_item otherwise. That return value can be 0, if a valid 694 * slot was found, 1 if there were no more leaves, and <0 if there was an error. 695 * 696 * It's recommended to use a separate variable for iter_ret and then use it to 697 * set the function return value so there's no confusion of the 0/1/errno 698 * values stemming from btrfs_search_slot. 699 */ 700 #define btrfs_for_each_slot(root, key, found_key, path, iter_ret) \ 701 for (iter_ret = btrfs_search_slot(NULL, (root), (key), (path), 0, 0); \ 702 (iter_ret) >= 0 && \ 703 (iter_ret = btrfs_get_next_valid_item((root), (found_key), (path))) == 0; \ 704 (path)->slots[0]++ \ 705 ) 706 707 int btrfs_next_old_item(struct btrfs_root *root, struct btrfs_path *path, u64 time_seq); 708 709 /* 710 * Search the tree again to find a leaf with greater keys. 711 * 712 * Returns 0 if it found something or 1 if there are no greater leaves. 713 * Returns < 0 on error. 714 */ 715 static inline int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) 716 { 717 return btrfs_next_old_leaf(root, path, 0); 718 } 719 720 static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p) 721 { 722 return btrfs_next_old_item(root, p, 0); 723 } 724 int btrfs_leaf_free_space(const struct extent_buffer *leaf); 725 726 static inline int is_fstree(u64 rootid) 727 { 728 if (rootid == BTRFS_FS_TREE_OBJECTID || 729 ((s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID && 730 !btrfs_qgroup_level(rootid))) 731 return 1; 732 return 0; 733 } 734 735 static inline bool btrfs_is_data_reloc_root(const struct btrfs_root *root) 736 { 737 return root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID; 738 } 739 740 u16 btrfs_csum_type_size(u16 type); 741 int btrfs_super_csum_size(const struct btrfs_super_block *s); 742 const char *btrfs_super_csum_name(u16 csum_type); 743 const char *btrfs_super_csum_driver(u16 csum_type); 744 size_t __attribute_const__ btrfs_get_num_csums(void); 745 746 /* 747 * We use page status Private2 to indicate there is an ordered extent with 748 * unfinished IO. 749 * 750 * Rename the Private2 accessors to Ordered, to improve readability. 751 */ 752 #define PageOrdered(page) PagePrivate2(page) 753 #define SetPageOrdered(page) SetPagePrivate2(page) 754 #define ClearPageOrdered(page) ClearPagePrivate2(page) 755 #define folio_test_ordered(folio) folio_test_private_2(folio) 756 #define folio_set_ordered(folio) folio_set_private_2(folio) 757 #define folio_clear_ordered(folio) folio_clear_private_2(folio) 758 759 #endif 760