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