Add scan of the btrfs log tree to btrfs-debug-tree
[btrfs-progs-unstable/devel.git] / ctree.h
blob8e7f88457fcca73f3dc45b0837368e197ee9ea45
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #ifndef __BTRFS__
20 #define __BTRFS__
22 #include "list.h"
23 #include "kerncompat.h"
24 #include "radix-tree.h"
25 #include "extent-cache.h"
26 #include "extent_io.h"
28 struct btrfs_root;
29 struct btrfs_trans_handle;
30 #define BTRFS_MAGIC "_BHRfS_M"
32 #define BTRFS_MAX_LEVEL 8
34 /* holds pointers to all of the tree roots */
35 #define BTRFS_ROOT_TREE_OBJECTID 1ULL
37 /* stores information about which extents are in use, and reference counts */
38 #define BTRFS_EXTENT_TREE_OBJECTID 2ULL
41 * chunk tree stores translations from logical -> physical block numbering
42 * the super block points to the chunk tree
44 #define BTRFS_CHUNK_TREE_OBJECTID 3ULL
47 * stores information about which areas of a given device are in use.
48 * one per device. The tree of tree roots points to the device tree
50 #define BTRFS_DEV_TREE_OBJECTID 4ULL
52 /* one per subvolume, storing files and directories */
53 #define BTRFS_FS_TREE_OBJECTID 5ULL
55 /* directory objectid inside the root tree */
56 #define BTRFS_ROOT_TREE_DIR_OBJECTID 6ULL
57 /* holds checksums of all the data extents */
58 #define BTRFS_CSUM_TREE_OBJECTID 7ULL
61 /* oprhan objectid for tracking unlinked/truncated files */
62 #define BTRFS_ORPHAN_OBJECTID -5ULL
64 /* does write ahead logging to speed up fsyncs */
65 #define BTRFS_TREE_LOG_OBJECTID -6ULL
66 #define BTRFS_TREE_LOG_FIXUP_OBJECTID -7ULL
68 /* space balancing */
69 #define BTRFS_TREE_RELOC_OBJECTID -8ULL
70 #define BTRFS_DATA_RELOC_TREE_OBJECTID -9ULL
73 * extent checksums all have this objectid
74 * this allows them to share the logging tree
75 * for fsyncs
77 #define BTRFS_EXTENT_CSUM_OBJECTID -10ULL
79 /* dummy objectid represents multiple objectids */
80 #define BTRFS_MULTIPLE_OBJECTIDS -255ULL
83 * All files have objectids in this range.
85 #define BTRFS_FIRST_FREE_OBJECTID 256ULL
86 #define BTRFS_LAST_FREE_OBJECTID -256ULL
87 #define BTRFS_FIRST_CHUNK_TREE_OBJECTID 256ULL
92 * the device items go into the chunk tree. The key is in the form
93 * [ 1 BTRFS_DEV_ITEM_KEY device_id ]
95 #define BTRFS_DEV_ITEMS_OBJECTID 1ULL
98 * we can actually store much bigger names, but lets not confuse the rest
99 * of linux
101 #define BTRFS_NAME_LEN 255
103 /* 32 bytes in various csum fields */
104 #define BTRFS_CSUM_SIZE 32
106 /* csum types */
107 #define BTRFS_CSUM_TYPE_CRC32 0
110 /* csum types */
111 #define BTRFS_CSUM_TYPE_CRC32 0
113 static int btrfs_csum_sizes[] = { 4, 0 };
115 /* four bytes for CRC32 */
116 #define BTRFS_CRC32_SIZE 4
117 #define BTRFS_EMPTY_DIR_SIZE 0
119 #define BTRFS_FT_UNKNOWN 0
120 #define BTRFS_FT_REG_FILE 1
121 #define BTRFS_FT_DIR 2
122 #define BTRFS_FT_CHRDEV 3
123 #define BTRFS_FT_BLKDEV 4
124 #define BTRFS_FT_FIFO 5
125 #define BTRFS_FT_SOCK 6
126 #define BTRFS_FT_SYMLINK 7
127 #define BTRFS_FT_XATTR 8
128 #define BTRFS_FT_MAX 9
131 * the key defines the order in the tree, and so it also defines (optimal)
132 * block layout. objectid corresonds to the inode number. The flags
133 * tells us things about the object, and is a kind of stream selector.
134 * so for a given inode, keys with flags of 1 might refer to the inode
135 * data, flags of 2 may point to file data in the btree and flags == 3
136 * may point to extents.
138 * offset is the starting byte offset for this key in the stream.
140 * btrfs_disk_key is in disk byte order. struct btrfs_key is always
141 * in cpu native order. Otherwise they are identical and their sizes
142 * should be the same (ie both packed)
144 struct btrfs_disk_key {
145 __le64 objectid;
146 u8 type;
147 __le64 offset;
148 } __attribute__ ((__packed__));
150 struct btrfs_key {
151 u64 objectid;
152 u8 type;
153 u64 offset;
154 } __attribute__ ((__packed__));
156 struct btrfs_mapping_tree {
157 struct cache_tree cache_tree;
160 #define BTRFS_UUID_SIZE 16
161 struct btrfs_dev_item {
162 /* the internal btrfs device id */
163 __le64 devid;
165 /* size of the device */
166 __le64 total_bytes;
168 /* bytes used */
169 __le64 bytes_used;
171 /* optimal io alignment for this device */
172 __le32 io_align;
174 /* optimal io width for this device */
175 __le32 io_width;
177 /* minimal io size for this device */
178 __le32 sector_size;
180 /* type and info about this device */
181 __le64 type;
183 /* expected generation for this device */
184 __le64 generation;
187 * starting byte of this partition on the device,
188 * to allowr for stripe alignment in the future
190 __le64 start_offset;
192 /* grouping information for allocation decisions */
193 __le32 dev_group;
195 /* seek speed 0-100 where 100 is fastest */
196 u8 seek_speed;
198 /* bandwidth 0-100 where 100 is fastest */
199 u8 bandwidth;
201 /* btrfs generated uuid for this device */
202 u8 uuid[BTRFS_UUID_SIZE];
204 /* uuid of FS who owns this device */
205 u8 fsid[BTRFS_UUID_SIZE];
206 } __attribute__ ((__packed__));
208 struct btrfs_stripe {
209 __le64 devid;
210 __le64 offset;
211 u8 dev_uuid[BTRFS_UUID_SIZE];
212 } __attribute__ ((__packed__));
214 struct btrfs_chunk {
215 /* size of this chunk in bytes */
216 __le64 length;
218 /* objectid of the root referencing this chunk */
219 __le64 owner;
221 __le64 stripe_len;
222 __le64 type;
224 /* optimal io alignment for this chunk */
225 __le32 io_align;
227 /* optimal io width for this chunk */
228 __le32 io_width;
230 /* minimal io size for this chunk */
231 __le32 sector_size;
233 /* 2^16 stripes is quite a lot, a second limit is the size of a single
234 * item in the btree
236 __le16 num_stripes;
238 /* sub stripes only matter for raid10 */
239 __le16 sub_stripes;
240 struct btrfs_stripe stripe;
241 /* additional stripes go here */
242 } __attribute__ ((__packed__));
244 static inline unsigned long btrfs_chunk_item_size(int num_stripes)
246 BUG_ON(num_stripes == 0);
247 return sizeof(struct btrfs_chunk) +
248 sizeof(struct btrfs_stripe) * (num_stripes - 1);
251 #define BTRFS_FSID_SIZE 16
252 #define BTRFS_HEADER_FLAG_WRITTEN (1 << 0)
255 * every tree block (leaf or node) starts with this header.
257 struct btrfs_header {
258 /* these first four must match the super block */
259 u8 csum[BTRFS_CSUM_SIZE];
260 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
261 __le64 bytenr; /* which block this node is supposed to live in */
262 __le64 flags;
264 /* allowed to be different from the super from here on down */
265 u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
266 __le64 generation;
267 __le64 owner;
268 __le32 nritems;
269 u8 level;
270 } __attribute__ ((__packed__));
272 #define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->nodesize - \
273 sizeof(struct btrfs_header)) / \
274 sizeof(struct btrfs_key_ptr))
275 #define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
276 #define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->leafsize))
277 #define BTRFS_MAX_INLINE_DATA_SIZE(r) (BTRFS_LEAF_DATA_SIZE(r) - \
278 sizeof(struct btrfs_item) - \
279 sizeof(struct btrfs_file_extent_item))
281 #define BTRFS_SUPER_FLAG_SEEDING (1ULL << 32)
282 #define BTRFS_SUPER_FLAG_METADUMP (1ULL << 33)
285 * this is a very generous portion of the super block, giving us
286 * room to translate 14 chunks with 3 stripes each.
288 #define BTRFS_SYSTEM_CHUNK_ARRAY_SIZE 2048
289 #define BTRFS_LABEL_SIZE 256
292 * the super block basically lists the main trees of the FS
293 * it currently lacks any block count etc etc
295 struct btrfs_super_block {
296 u8 csum[BTRFS_CSUM_SIZE];
297 /* the first 3 fields must match struct btrfs_header */
298 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
299 __le64 bytenr; /* this block number */
300 __le64 flags;
302 /* allowed to be different from the btrfs_header from here own down */
303 __le64 magic;
304 __le64 generation;
305 __le64 root;
306 __le64 chunk_root;
307 __le64 log_root;
309 /* this will help find the new super based on the log root */
310 __le64 log_root_transid;
311 __le64 total_bytes;
312 __le64 bytes_used;
313 __le64 root_dir_objectid;
314 __le64 num_devices;
315 __le32 sectorsize;
316 __le32 nodesize;
317 __le32 leafsize;
318 __le32 stripesize;
319 __le32 sys_chunk_array_size;
320 __le64 chunk_root_generation;
321 __le64 compat_flags;
322 __le64 compat_ro_flags;
323 __le64 incompat_flags;
324 __le16 csum_type;
325 u8 root_level;
326 u8 chunk_root_level;
327 u8 log_root_level;
328 struct btrfs_dev_item dev_item;
330 char label[BTRFS_LABEL_SIZE];
332 /* future expansion */
333 __le64 reserved[32];
334 u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE];
335 } __attribute__ ((__packed__));
338 * Compat flags that we support. If any incompat flags are set other than the
339 * ones specified below then we will fail to mount
341 #define BTRFS_FEATURE_COMPAT_SUPP 0x0
342 #define BTRFS_FEATURE_COMPAT_RO_SUPP 0x0
343 #define BTRFS_FEATURE_INCOMPAT_SUPP 0x0
346 * A leaf is full of items. offset and size tell us where to find
347 * the item in the leaf (relative to the start of the data area)
349 struct btrfs_item {
350 struct btrfs_disk_key key;
351 __le32 offset;
352 __le32 size;
353 } __attribute__ ((__packed__));
356 * leaves have an item area and a data area:
357 * [item0, item1....itemN] [free space] [dataN...data1, data0]
359 * The data is separate from the items to get the keys closer together
360 * during searches.
362 struct btrfs_leaf {
363 struct btrfs_header header;
364 struct btrfs_item items[];
365 } __attribute__ ((__packed__));
368 * all non-leaf blocks are nodes, they hold only keys and pointers to
369 * other blocks
371 struct btrfs_key_ptr {
372 struct btrfs_disk_key key;
373 __le64 blockptr;
374 __le64 generation;
375 } __attribute__ ((__packed__));
377 struct btrfs_node {
378 struct btrfs_header header;
379 struct btrfs_key_ptr ptrs[];
380 } __attribute__ ((__packed__));
383 * btrfs_paths remember the path taken from the root down to the leaf.
384 * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point
385 * to any other levels that are present.
387 * The slots array records the index of the item or block pointer
388 * used while walking the tree.
390 struct btrfs_path {
391 struct extent_buffer *nodes[BTRFS_MAX_LEVEL];
392 int slots[BTRFS_MAX_LEVEL];
393 int reada;
394 int lowest_level;
397 * set by btrfs_split_item, tells search_slot to keep all locks
398 * and to force calls to keep space in the nodes
400 int search_for_split;
404 * items in the extent btree are used to record the objectid of the
405 * owner of the block and the number of references
407 struct btrfs_extent_item {
408 __le32 refs;
409 } __attribute__ ((__packed__));
411 struct btrfs_extent_ref {
412 __le64 root;
413 __le64 generation;
414 __le64 objectid;
415 __le32 num_refs;
416 } __attribute__ ((__packed__));
418 /* dev extents record free space on individual devices. The owner
419 * field points back to the chunk allocation mapping tree that allocated
420 * the extent. The chunk tree uuid field is a way to double check the owner
422 struct btrfs_dev_extent {
423 __le64 chunk_tree;
424 __le64 chunk_objectid;
425 __le64 chunk_offset;
426 __le64 length;
427 u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
428 } __attribute__ ((__packed__));
430 struct btrfs_inode_ref {
431 __le64 index;
432 __le16 name_len;
433 /* name goes here */
434 } __attribute__ ((__packed__));
436 struct btrfs_timespec {
437 __le64 sec;
438 __le32 nsec;
439 } __attribute__ ((__packed__));
441 typedef enum {
442 BTRFS_COMPRESS_NONE = 0,
443 BTRFS_COMPRESS_ZLIB = 1,
444 BTRFS_COMPRESS_LAST = 2,
445 } btrfs_compression_type;
447 /* we don't understand any encryption methods right now */
448 typedef enum {
449 BTRFS_ENCRYPTION_NONE = 0,
450 BTRFS_ENCRYPTION_LAST = 1,
451 } btrfs_encryption_type;
453 struct btrfs_inode_item {
454 /* nfs style generation number */
455 __le64 generation;
456 /* transid that last touched this inode */
457 __le64 transid;
458 __le64 size;
459 __le64 nbytes;
460 __le64 block_group;
461 __le32 nlink;
462 __le32 uid;
463 __le32 gid;
464 __le32 mode;
465 __le64 rdev;
466 __le64 flags;
468 /* modification sequence number for NFS */
469 __le64 sequence;
472 * a little future expansion, for more than this we can
473 * just grow the inode item and version it
475 __le64 reserved[4];
476 struct btrfs_timespec atime;
477 struct btrfs_timespec ctime;
478 struct btrfs_timespec mtime;
479 struct btrfs_timespec otime;
480 } __attribute__ ((__packed__));
482 struct btrfs_dir_log_item {
483 __le64 end;
484 } __attribute__ ((__packed__));
486 struct btrfs_dir_item {
487 struct btrfs_disk_key location;
488 __le64 transid;
489 __le16 data_len;
490 __le16 name_len;
491 u8 type;
492 } __attribute__ ((__packed__));
494 struct btrfs_root_item {
495 struct btrfs_inode_item inode;
496 __le64 generation;
497 __le64 root_dirid;
498 __le64 bytenr;
499 __le64 byte_limit;
500 __le64 bytes_used;
501 __le64 last_snapshot;
502 __le64 flags;
503 __le32 refs;
504 struct btrfs_disk_key drop_progress;
505 u8 drop_level;
506 u8 level;
507 } __attribute__ ((__packed__));
510 * this is used for both forward and backward root refs
512 struct btrfs_root_ref {
513 __le64 dirid;
514 __le64 sequence;
515 __le16 name_len;
516 } __attribute__ ((__packed__));
518 #define BTRFS_FILE_EXTENT_INLINE 0
519 #define BTRFS_FILE_EXTENT_REG 1
520 #define BTRFS_FILE_EXTENT_PREALLOC 2
522 struct btrfs_file_extent_item {
524 * transaction id that created this extent
526 __le64 generation;
528 * max number of bytes to hold this extent in ram
529 * when we split a compressed extent we can't know how big
530 * each of the resulting pieces will be. So, this is
531 * an upper limit on the size of the extent in ram instead of
532 * an exact limit.
534 __le64 ram_bytes;
537 * 32 bits for the various ways we might encode the data,
538 * including compression and encryption. If any of these
539 * are set to something a given disk format doesn't understand
540 * it is treated like an incompat flag for reading and writing,
541 * but not for stat.
543 u8 compression;
544 u8 encryption;
545 __le16 other_encoding; /* spare for later use */
547 /* are we inline data or a real extent? */
548 u8 type;
551 * disk space consumed by the extent, checksum blocks are included
552 * in these numbers
554 __le64 disk_bytenr;
555 __le64 disk_num_bytes;
557 * the logical offset in file blocks (no csums)
558 * this extent record is for. This allows a file extent to point
559 * into the middle of an existing extent on disk, sharing it
560 * between two snapshots (useful if some bytes in the middle of the
561 * extent have changed
563 __le64 offset;
565 * the logical number of file blocks (no csums included)
567 __le64 num_bytes;
569 } __attribute__ ((__packed__));
571 struct btrfs_csum_item {
572 u8 csum;
573 } __attribute__ ((__packed__));
575 /* tag for the radix tree of block groups in ram */
576 #define BTRFS_BLOCK_GROUP_DATA (1 << 0)
577 #define BTRFS_BLOCK_GROUP_SYSTEM (1 << 1)
578 #define BTRFS_BLOCK_GROUP_METADATA (1 << 2)
579 #define BTRFS_BLOCK_GROUP_RAID0 (1 << 3)
580 #define BTRFS_BLOCK_GROUP_RAID1 (1 << 4)
581 #define BTRFS_BLOCK_GROUP_DUP (1 << 5)
582 #define BTRFS_BLOCK_GROUP_RAID10 (1 << 6)
584 struct btrfs_block_group_item {
585 __le64 used;
586 __le64 chunk_objectid;
587 __le64 flags;
588 } __attribute__ ((__packed__));
590 struct btrfs_space_info {
591 u64 flags;
592 u64 total_bytes;
593 u64 bytes_used;
594 u64 bytes_pinned;
595 int full;
596 struct list_head list;
599 struct btrfs_block_group_cache {
600 struct cache_extent cache;
601 struct btrfs_key key;
602 struct btrfs_block_group_item item;
603 struct btrfs_space_info *space_info;
604 u64 pinned;
605 u64 flags;
606 int cached;
607 int ro;
610 struct btrfs_extent_ops {
611 int (*alloc_extent)(struct btrfs_root *root, u64 num_bytes,
612 u64 hint_byte, struct btrfs_key *ins);
613 int (*free_extent)(struct btrfs_root *root, u64 bytenr,
614 u64 num_bytes);
617 struct btrfs_device;
618 struct btrfs_fs_devices;
619 struct btrfs_fs_info {
620 u8 fsid[BTRFS_FSID_SIZE];
621 u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
622 struct btrfs_root *fs_root;
623 struct btrfs_root *extent_root;
624 struct btrfs_root *tree_root;
625 struct btrfs_root *chunk_root;
626 struct btrfs_root *dev_root;
627 struct btrfs_root *csum_root;
629 /* the log root tree is a directory of all the other log roots */
630 struct btrfs_root *log_root_tree;
632 struct extent_io_tree extent_cache;
633 struct extent_io_tree free_space_cache;
634 struct extent_io_tree block_group_cache;
635 struct extent_io_tree pinned_extents;
636 struct extent_io_tree pending_del;
637 struct extent_io_tree extent_ins;
639 /* logical->physical extent mapping */
640 struct btrfs_mapping_tree mapping_tree;
642 u64 generation;
643 u64 last_trans_committed;
645 u64 avail_data_alloc_bits;
646 u64 avail_metadata_alloc_bits;
647 u64 avail_system_alloc_bits;
648 u64 data_alloc_profile;
649 u64 metadata_alloc_profile;
650 u64 system_alloc_profile;
651 u64 alloc_start;
653 struct btrfs_trans_handle *running_transaction;
654 struct btrfs_super_block super_copy;
655 struct mutex fs_mutex;
657 u64 super_bytenr;
658 u64 total_pinned;
660 struct btrfs_extent_ops *extent_ops;
661 struct list_head dirty_cowonly_roots;
663 struct btrfs_fs_devices *fs_devices;
664 struct list_head space_info;
665 int system_allocs;
666 int readonly;
670 * in ram representation of the tree. extent_root is used for all allocations
671 * and for the extent tree extent_root root.
673 struct btrfs_root {
674 struct extent_buffer *node;
675 struct extent_buffer *commit_root;
676 struct btrfs_root_item root_item;
677 struct btrfs_key root_key;
678 struct btrfs_fs_info *fs_info;
679 u64 objectid;
680 u64 last_trans;
682 /* data allocations are done in sectorsize units */
683 u32 sectorsize;
685 /* node allocations are done in nodesize units */
686 u32 nodesize;
688 /* leaf allocations are done in leafsize units */
689 u32 leafsize;
691 /* leaf allocations are done in leafsize units */
692 u32 stripesize;
694 int ref_cows;
695 int track_dirty;
698 u32 type;
699 u64 highest_inode;
700 u64 last_inode_alloc;
702 /* the dirty list is only used by non-reference counted roots */
703 struct list_head dirty_list;
707 * inode items have the data typically returned from stat and store other
708 * info about object characteristics. There is one for every file and dir in
709 * the FS
711 #define BTRFS_INODE_ITEM_KEY 1
712 #define BTRFS_INODE_REF_KEY 12
713 #define BTRFS_XATTR_ITEM_KEY 24
714 #define BTRFS_ORPHAN_ITEM_KEY 48
716 #define BTRFS_DIR_LOG_ITEM_KEY 60
717 #define BTRFS_DIR_LOG_INDEX_KEY 72
719 * dir items are the name -> inode pointers in a directory. There is one
720 * for every name in a directory.
722 #define BTRFS_DIR_ITEM_KEY 84
723 #define BTRFS_DIR_INDEX_KEY 96
726 * extent data is for file data
728 #define BTRFS_EXTENT_DATA_KEY 108
731 * csum items have the checksums for data in the extents
733 #define BTRFS_CSUM_ITEM_KEY 120
735 * extent csums are stored in a separate tree and hold csums for
736 * an entire extent on disk.
738 #define BTRFS_EXTENT_CSUM_KEY 128
741 * root items point to tree roots. There are typically in the root
742 * tree used by the super block to find all the other trees
744 #define BTRFS_ROOT_ITEM_KEY 132
747 * root backrefs tie subvols and snapshots to the directory entries that
748 * reference them
750 #define BTRFS_ROOT_BACKREF_KEY 144
753 * root refs make a fast index for listing all of the snapshots and
754 * subvolumes referenced by a given root. They point directly to the
755 * directory item in the root that references the subvol
757 #define BTRFS_ROOT_REF_KEY 156
760 * extent items are in the extent map tree. These record which blocks
761 * are used, and how many references there are to each block
763 #define BTRFS_EXTENT_ITEM_KEY 168
764 #define BTRFS_EXTENT_REF_KEY 180
767 * block groups give us hints into the extent allocation trees. Which
768 * blocks are free etc etc
770 #define BTRFS_BLOCK_GROUP_ITEM_KEY 192
772 #define BTRFS_DEV_EXTENT_KEY 204
773 #define BTRFS_DEV_ITEM_KEY 216
774 #define BTRFS_CHUNK_ITEM_KEY 228
777 * string items are for debugging. They just store a short string of
778 * data in the FS
780 #define BTRFS_STRING_ITEM_KEY 253
782 * Inode flags
784 #define BTRFS_INODE_NODATASUM (1 << 0)
785 #define BTRFS_INODE_NODATACOW (1 << 1)
786 #define BTRFS_INODE_READONLY (1 << 2)
788 #define read_eb_member(eb, ptr, type, member, result) ( \
789 read_extent_buffer(eb, (char *)(result), \
790 ((unsigned long)(ptr)) + \
791 offsetof(type, member), \
792 sizeof(((type *)0)->member)))
794 #define write_eb_member(eb, ptr, type, member, result) ( \
795 write_extent_buffer(eb, (char *)(result), \
796 ((unsigned long)(ptr)) + \
797 offsetof(type, member), \
798 sizeof(((type *)0)->member)))
800 #define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits) \
801 static inline u##bits btrfs_##name(struct extent_buffer *eb) \
803 struct btrfs_header *h = (struct btrfs_header *)eb->data; \
804 return le##bits##_to_cpu(h->member); \
806 static inline void btrfs_set_##name(struct extent_buffer *eb, \
807 u##bits val) \
809 struct btrfs_header *h = (struct btrfs_header *)eb->data; \
810 h->member = cpu_to_le##bits(val); \
813 #define BTRFS_SETGET_FUNCS(name, type, member, bits) \
814 static inline u##bits btrfs_##name(struct extent_buffer *eb, \
815 type *s) \
817 unsigned long offset = (unsigned long)s; \
818 type *p = (type *) (eb->data + offset); \
819 return le##bits##_to_cpu(p->member); \
821 static inline void btrfs_set_##name(struct extent_buffer *eb, \
822 type *s, u##bits val) \
824 unsigned long offset = (unsigned long)s; \
825 type *p = (type *) (eb->data + offset); \
826 p->member = cpu_to_le##bits(val); \
829 #define BTRFS_SETGET_STACK_FUNCS(name, type, member, bits) \
830 static inline u##bits btrfs_##name(type *s) \
832 return le##bits##_to_cpu(s->member); \
834 static inline void btrfs_set_##name(type *s, u##bits val) \
836 s->member = cpu_to_le##bits(val); \
839 BTRFS_SETGET_FUNCS(device_type, struct btrfs_dev_item, type, 64);
840 BTRFS_SETGET_FUNCS(device_total_bytes, struct btrfs_dev_item, total_bytes, 64);
841 BTRFS_SETGET_FUNCS(device_bytes_used, struct btrfs_dev_item, bytes_used, 64);
842 BTRFS_SETGET_FUNCS(device_io_align, struct btrfs_dev_item, io_align, 32);
843 BTRFS_SETGET_FUNCS(device_io_width, struct btrfs_dev_item, io_width, 32);
844 BTRFS_SETGET_FUNCS(device_start_offset, struct btrfs_dev_item,
845 start_offset, 64);
846 BTRFS_SETGET_FUNCS(device_sector_size, struct btrfs_dev_item, sector_size, 32);
847 BTRFS_SETGET_FUNCS(device_id, struct btrfs_dev_item, devid, 64);
848 BTRFS_SETGET_FUNCS(device_group, struct btrfs_dev_item, dev_group, 32);
849 BTRFS_SETGET_FUNCS(device_seek_speed, struct btrfs_dev_item, seek_speed, 8);
850 BTRFS_SETGET_FUNCS(device_bandwidth, struct btrfs_dev_item, bandwidth, 8);
851 BTRFS_SETGET_FUNCS(device_generation, struct btrfs_dev_item, generation, 64);
853 BTRFS_SETGET_STACK_FUNCS(stack_device_type, struct btrfs_dev_item, type, 64);
854 BTRFS_SETGET_STACK_FUNCS(stack_device_total_bytes, struct btrfs_dev_item,
855 total_bytes, 64);
856 BTRFS_SETGET_STACK_FUNCS(stack_device_bytes_used, struct btrfs_dev_item,
857 bytes_used, 64);
858 BTRFS_SETGET_STACK_FUNCS(stack_device_io_align, struct btrfs_dev_item,
859 io_align, 32);
860 BTRFS_SETGET_STACK_FUNCS(stack_device_io_width, struct btrfs_dev_item,
861 io_width, 32);
862 BTRFS_SETGET_STACK_FUNCS(stack_device_sector_size, struct btrfs_dev_item,
863 sector_size, 32);
864 BTRFS_SETGET_STACK_FUNCS(stack_device_id, struct btrfs_dev_item, devid, 64);
865 BTRFS_SETGET_STACK_FUNCS(stack_device_group, struct btrfs_dev_item,
866 dev_group, 32);
867 BTRFS_SETGET_STACK_FUNCS(stack_device_seek_speed, struct btrfs_dev_item,
868 seek_speed, 8);
869 BTRFS_SETGET_STACK_FUNCS(stack_device_bandwidth, struct btrfs_dev_item,
870 bandwidth, 8);
871 BTRFS_SETGET_STACK_FUNCS(stack_device_generation, struct btrfs_dev_item,
872 generation, 64);
874 static inline char *btrfs_device_uuid(struct btrfs_dev_item *d)
876 return (char *)d + offsetof(struct btrfs_dev_item, uuid);
879 static inline char *btrfs_device_fsid(struct btrfs_dev_item *d)
881 return (char *)d + offsetof(struct btrfs_dev_item, fsid);
884 BTRFS_SETGET_FUNCS(chunk_length, struct btrfs_chunk, length, 64);
885 BTRFS_SETGET_FUNCS(chunk_owner, struct btrfs_chunk, owner, 64);
886 BTRFS_SETGET_FUNCS(chunk_stripe_len, struct btrfs_chunk, stripe_len, 64);
887 BTRFS_SETGET_FUNCS(chunk_io_align, struct btrfs_chunk, io_align, 32);
888 BTRFS_SETGET_FUNCS(chunk_io_width, struct btrfs_chunk, io_width, 32);
889 BTRFS_SETGET_FUNCS(chunk_sector_size, struct btrfs_chunk, sector_size, 32);
890 BTRFS_SETGET_FUNCS(chunk_type, struct btrfs_chunk, type, 64);
891 BTRFS_SETGET_FUNCS(chunk_num_stripes, struct btrfs_chunk, num_stripes, 16);
892 BTRFS_SETGET_FUNCS(chunk_sub_stripes, struct btrfs_chunk, sub_stripes, 16);
893 BTRFS_SETGET_FUNCS(stripe_devid, struct btrfs_stripe, devid, 64);
894 BTRFS_SETGET_FUNCS(stripe_offset, struct btrfs_stripe, offset, 64);
896 static inline char *btrfs_stripe_dev_uuid(struct btrfs_stripe *s)
898 return (char *)s + offsetof(struct btrfs_stripe, dev_uuid);
901 BTRFS_SETGET_STACK_FUNCS(stack_chunk_length, struct btrfs_chunk, length, 64);
902 BTRFS_SETGET_STACK_FUNCS(stack_chunk_owner, struct btrfs_chunk, owner, 64);
903 BTRFS_SETGET_STACK_FUNCS(stack_chunk_stripe_len, struct btrfs_chunk,
904 stripe_len, 64);
905 BTRFS_SETGET_STACK_FUNCS(stack_chunk_io_align, struct btrfs_chunk,
906 io_align, 32);
907 BTRFS_SETGET_STACK_FUNCS(stack_chunk_io_width, struct btrfs_chunk,
908 io_width, 32);
909 BTRFS_SETGET_STACK_FUNCS(stack_chunk_sector_size, struct btrfs_chunk,
910 sector_size, 32);
911 BTRFS_SETGET_STACK_FUNCS(stack_chunk_type, struct btrfs_chunk, type, 64);
912 BTRFS_SETGET_STACK_FUNCS(stack_chunk_num_stripes, struct btrfs_chunk,
913 num_stripes, 16);
914 BTRFS_SETGET_STACK_FUNCS(stack_chunk_sub_stripes, struct btrfs_chunk,
915 sub_stripes, 16);
916 BTRFS_SETGET_STACK_FUNCS(stack_stripe_devid, struct btrfs_stripe, devid, 64);
917 BTRFS_SETGET_STACK_FUNCS(stack_stripe_offset, struct btrfs_stripe, offset, 64);
919 static inline struct btrfs_stripe *btrfs_stripe_nr(struct btrfs_chunk *c,
920 int nr)
922 unsigned long offset = (unsigned long)c;
923 offset += offsetof(struct btrfs_chunk, stripe);
924 offset += nr * sizeof(struct btrfs_stripe);
925 return (struct btrfs_stripe *)offset;
928 static inline char *btrfs_stripe_dev_uuid_nr(struct btrfs_chunk *c, int nr)
930 return btrfs_stripe_dev_uuid(btrfs_stripe_nr(c, nr));
933 static inline u64 btrfs_stripe_offset_nr(struct extent_buffer *eb,
934 struct btrfs_chunk *c, int nr)
936 return btrfs_stripe_offset(eb, btrfs_stripe_nr(c, nr));
939 static inline void btrfs_set_stripe_offset_nr(struct extent_buffer *eb,
940 struct btrfs_chunk *c, int nr,
941 u64 val)
943 btrfs_set_stripe_offset(eb, btrfs_stripe_nr(c, nr), val);
946 static inline u64 btrfs_stripe_devid_nr(struct extent_buffer *eb,
947 struct btrfs_chunk *c, int nr)
949 return btrfs_stripe_devid(eb, btrfs_stripe_nr(c, nr));
952 static inline void btrfs_set_stripe_devid_nr(struct extent_buffer *eb,
953 struct btrfs_chunk *c, int nr,
954 u64 val)
956 btrfs_set_stripe_devid(eb, btrfs_stripe_nr(c, nr), val);
959 /* struct btrfs_block_group_item */
960 BTRFS_SETGET_STACK_FUNCS(block_group_used, struct btrfs_block_group_item,
961 used, 64);
962 BTRFS_SETGET_FUNCS(disk_block_group_used, struct btrfs_block_group_item,
963 used, 64);
964 BTRFS_SETGET_STACK_FUNCS(block_group_chunk_objectid,
965 struct btrfs_block_group_item, chunk_objectid, 64);
967 BTRFS_SETGET_FUNCS(disk_block_group_chunk_objectid,
968 struct btrfs_block_group_item, chunk_objectid, 64);
969 BTRFS_SETGET_FUNCS(disk_block_group_flags,
970 struct btrfs_block_group_item, flags, 64);
971 BTRFS_SETGET_STACK_FUNCS(block_group_flags,
972 struct btrfs_block_group_item, flags, 64);
974 /* struct btrfs_inode_ref */
975 BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16);
976 BTRFS_SETGET_FUNCS(inode_ref_index, struct btrfs_inode_ref, index, 64);
978 /* struct btrfs_inode_item */
979 BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64);
980 BTRFS_SETGET_FUNCS(inode_sequence, struct btrfs_inode_item, sequence, 64);
981 BTRFS_SETGET_FUNCS(inode_transid, struct btrfs_inode_item, transid, 64);
982 BTRFS_SETGET_FUNCS(inode_size, struct btrfs_inode_item, size, 64);
983 BTRFS_SETGET_FUNCS(inode_nbytes, struct btrfs_inode_item, nbytes, 64);
984 BTRFS_SETGET_FUNCS(inode_block_group, struct btrfs_inode_item, block_group, 64);
985 BTRFS_SETGET_FUNCS(inode_nlink, struct btrfs_inode_item, nlink, 32);
986 BTRFS_SETGET_FUNCS(inode_uid, struct btrfs_inode_item, uid, 32);
987 BTRFS_SETGET_FUNCS(inode_gid, struct btrfs_inode_item, gid, 32);
988 BTRFS_SETGET_FUNCS(inode_mode, struct btrfs_inode_item, mode, 32);
989 BTRFS_SETGET_FUNCS(inode_rdev, struct btrfs_inode_item, rdev, 64);
990 BTRFS_SETGET_FUNCS(inode_flags, struct btrfs_inode_item, flags, 64);
992 BTRFS_SETGET_STACK_FUNCS(stack_inode_generation,
993 struct btrfs_inode_item, generation, 64);
994 BTRFS_SETGET_STACK_FUNCS(stack_inode_sequence,
995 struct btrfs_inode_item, generation, 64);
996 BTRFS_SETGET_STACK_FUNCS(stack_inode_size,
997 struct btrfs_inode_item, size, 64);
998 BTRFS_SETGET_STACK_FUNCS(stack_inode_nbytes,
999 struct btrfs_inode_item, nbytes, 64);
1000 BTRFS_SETGET_STACK_FUNCS(stack_inode_block_group,
1001 struct btrfs_inode_item, block_group, 64);
1002 BTRFS_SETGET_STACK_FUNCS(stack_inode_nlink,
1003 struct btrfs_inode_item, nlink, 32);
1004 BTRFS_SETGET_STACK_FUNCS(stack_inode_uid,
1005 struct btrfs_inode_item, uid, 32);
1006 BTRFS_SETGET_STACK_FUNCS(stack_inode_gid,
1007 struct btrfs_inode_item, gid, 32);
1008 BTRFS_SETGET_STACK_FUNCS(stack_inode_mode,
1009 struct btrfs_inode_item, mode, 32);
1010 BTRFS_SETGET_STACK_FUNCS(stack_inode_rdev,
1011 struct btrfs_inode_item, rdev, 64);
1012 BTRFS_SETGET_STACK_FUNCS(stack_inode_flags,
1013 struct btrfs_inode_item, flags, 64);
1015 static inline struct btrfs_timespec *
1016 btrfs_inode_atime(struct btrfs_inode_item *inode_item)
1018 unsigned long ptr = (unsigned long)inode_item;
1019 ptr += offsetof(struct btrfs_inode_item, atime);
1020 return (struct btrfs_timespec *)ptr;
1023 static inline struct btrfs_timespec *
1024 btrfs_inode_mtime(struct btrfs_inode_item *inode_item)
1026 unsigned long ptr = (unsigned long)inode_item;
1027 ptr += offsetof(struct btrfs_inode_item, mtime);
1028 return (struct btrfs_timespec *)ptr;
1031 static inline struct btrfs_timespec *
1032 btrfs_inode_ctime(struct btrfs_inode_item *inode_item)
1034 unsigned long ptr = (unsigned long)inode_item;
1035 ptr += offsetof(struct btrfs_inode_item, ctime);
1036 return (struct btrfs_timespec *)ptr;
1039 static inline struct btrfs_timespec *
1040 btrfs_inode_otime(struct btrfs_inode_item *inode_item)
1042 unsigned long ptr = (unsigned long)inode_item;
1043 ptr += offsetof(struct btrfs_inode_item, otime);
1044 return (struct btrfs_timespec *)ptr;
1047 BTRFS_SETGET_FUNCS(timespec_sec, struct btrfs_timespec, sec, 64);
1048 BTRFS_SETGET_FUNCS(timespec_nsec, struct btrfs_timespec, nsec, 32);
1049 BTRFS_SETGET_STACK_FUNCS(stack_timespec_sec, struct btrfs_timespec,
1050 sec, 64);
1051 BTRFS_SETGET_STACK_FUNCS(stack_timespec_nsec, struct btrfs_timespec,
1052 nsec, 32);
1054 /* struct btrfs_dev_extent */
1055 BTRFS_SETGET_FUNCS(dev_extent_chunk_tree, struct btrfs_dev_extent,
1056 chunk_tree, 64);
1057 BTRFS_SETGET_FUNCS(dev_extent_chunk_objectid, struct btrfs_dev_extent,
1058 chunk_objectid, 64);
1059 BTRFS_SETGET_FUNCS(dev_extent_chunk_offset, struct btrfs_dev_extent,
1060 chunk_offset, 64);
1061 BTRFS_SETGET_FUNCS(dev_extent_length, struct btrfs_dev_extent, length, 64);
1063 static inline u8 *btrfs_dev_extent_chunk_tree_uuid(struct btrfs_dev_extent *dev)
1065 unsigned long ptr = offsetof(struct btrfs_dev_extent, chunk_tree_uuid);
1066 return (u8 *)((unsigned long)dev + ptr);
1069 /* struct btrfs_extent_ref */
1070 BTRFS_SETGET_FUNCS(ref_root, struct btrfs_extent_ref, root, 64);
1071 BTRFS_SETGET_FUNCS(ref_generation, struct btrfs_extent_ref, generation, 64);
1072 BTRFS_SETGET_FUNCS(ref_objectid, struct btrfs_extent_ref, objectid, 64);
1073 BTRFS_SETGET_FUNCS(ref_num_refs, struct btrfs_extent_ref, num_refs, 32);
1075 BTRFS_SETGET_STACK_FUNCS(stack_ref_root, struct btrfs_extent_ref, root, 64);
1076 BTRFS_SETGET_STACK_FUNCS(stack_ref_generation, struct btrfs_extent_ref,
1077 generation, 64);
1078 BTRFS_SETGET_STACK_FUNCS(stack_ref_objectid, struct btrfs_extent_ref,
1079 objectid, 64);
1080 BTRFS_SETGET_STACK_FUNCS(stack_ref_num_refs, struct btrfs_extent_ref,
1081 num_refs, 32);
1083 /* struct btrfs_extent_item */
1084 BTRFS_SETGET_FUNCS(extent_refs, struct btrfs_extent_item, refs, 32);
1085 BTRFS_SETGET_STACK_FUNCS(stack_extent_refs, struct btrfs_extent_item,
1086 refs, 32);
1088 /* struct btrfs_node */
1089 BTRFS_SETGET_FUNCS(key_blockptr, struct btrfs_key_ptr, blockptr, 64);
1090 BTRFS_SETGET_FUNCS(key_generation, struct btrfs_key_ptr, generation, 64);
1092 static inline u64 btrfs_node_blockptr(struct extent_buffer *eb, int nr)
1094 unsigned long ptr;
1095 ptr = offsetof(struct btrfs_node, ptrs) +
1096 sizeof(struct btrfs_key_ptr) * nr;
1097 return btrfs_key_blockptr(eb, (struct btrfs_key_ptr *)ptr);
1100 static inline void btrfs_set_node_blockptr(struct extent_buffer *eb,
1101 int nr, u64 val)
1103 unsigned long ptr;
1104 ptr = offsetof(struct btrfs_node, ptrs) +
1105 sizeof(struct btrfs_key_ptr) * nr;
1106 btrfs_set_key_blockptr(eb, (struct btrfs_key_ptr *)ptr, val);
1109 static inline u64 btrfs_node_ptr_generation(struct extent_buffer *eb, int nr)
1111 unsigned long ptr;
1112 ptr = offsetof(struct btrfs_node, ptrs) +
1113 sizeof(struct btrfs_key_ptr) * nr;
1114 return btrfs_key_generation(eb, (struct btrfs_key_ptr *)ptr);
1117 static inline void btrfs_set_node_ptr_generation(struct extent_buffer *eb,
1118 int nr, u64 val)
1120 unsigned long ptr;
1121 ptr = offsetof(struct btrfs_node, ptrs) +
1122 sizeof(struct btrfs_key_ptr) * nr;
1123 btrfs_set_key_generation(eb, (struct btrfs_key_ptr *)ptr, val);
1126 static inline unsigned long btrfs_node_key_ptr_offset(int nr)
1128 return offsetof(struct btrfs_node, ptrs) +
1129 sizeof(struct btrfs_key_ptr) * nr;
1132 static inline void btrfs_node_key(struct extent_buffer *eb,
1133 struct btrfs_disk_key *disk_key, int nr)
1135 unsigned long ptr;
1136 ptr = btrfs_node_key_ptr_offset(nr);
1137 read_eb_member(eb, (struct btrfs_key_ptr *)ptr,
1138 struct btrfs_key_ptr, key, disk_key);
1141 static inline void btrfs_set_node_key(struct extent_buffer *eb,
1142 struct btrfs_disk_key *disk_key, int nr)
1144 unsigned long ptr;
1145 ptr = btrfs_node_key_ptr_offset(nr);
1146 write_eb_member(eb, (struct btrfs_key_ptr *)ptr,
1147 struct btrfs_key_ptr, key, disk_key);
1150 /* struct btrfs_item */
1151 BTRFS_SETGET_FUNCS(item_offset, struct btrfs_item, offset, 32);
1152 BTRFS_SETGET_FUNCS(item_size, struct btrfs_item, size, 32);
1154 static inline unsigned long btrfs_item_nr_offset(int nr)
1156 return offsetof(struct btrfs_leaf, items) +
1157 sizeof(struct btrfs_item) * nr;
1160 static inline struct btrfs_item *btrfs_item_nr(struct extent_buffer *eb,
1161 int nr)
1163 return (struct btrfs_item *)btrfs_item_nr_offset(nr);
1166 static inline u32 btrfs_item_end(struct extent_buffer *eb,
1167 struct btrfs_item *item)
1169 return btrfs_item_offset(eb, item) + btrfs_item_size(eb, item);
1172 static inline u32 btrfs_item_end_nr(struct extent_buffer *eb, int nr)
1174 return btrfs_item_end(eb, btrfs_item_nr(eb, nr));
1177 static inline u32 btrfs_item_offset_nr(struct extent_buffer *eb, int nr)
1179 return btrfs_item_offset(eb, btrfs_item_nr(eb, nr));
1182 static inline u32 btrfs_item_size_nr(struct extent_buffer *eb, int nr)
1184 return btrfs_item_size(eb, btrfs_item_nr(eb, nr));
1187 static inline void btrfs_item_key(struct extent_buffer *eb,
1188 struct btrfs_disk_key *disk_key, int nr)
1190 struct btrfs_item *item = btrfs_item_nr(eb, nr);
1191 read_eb_member(eb, item, struct btrfs_item, key, disk_key);
1194 static inline void btrfs_set_item_key(struct extent_buffer *eb,
1195 struct btrfs_disk_key *disk_key, int nr)
1197 struct btrfs_item *item = btrfs_item_nr(eb, nr);
1198 write_eb_member(eb, item, struct btrfs_item, key, disk_key);
1201 BTRFS_SETGET_FUNCS(dir_log_end, struct btrfs_dir_log_item, end, 64);
1204 * struct btrfs_root_ref
1206 BTRFS_SETGET_FUNCS(root_ref_dirid, struct btrfs_root_ref, dirid, 64);
1207 BTRFS_SETGET_FUNCS(root_ref_sequence, struct btrfs_root_ref, sequence, 64);
1208 BTRFS_SETGET_FUNCS(root_ref_name_len, struct btrfs_root_ref, name_len, 16);
1210 /* struct btrfs_dir_item */
1211 BTRFS_SETGET_FUNCS(dir_data_len, struct btrfs_dir_item, data_len, 16);
1212 BTRFS_SETGET_FUNCS(dir_type, struct btrfs_dir_item, type, 8);
1213 BTRFS_SETGET_FUNCS(dir_name_len, struct btrfs_dir_item, name_len, 16);
1214 BTRFS_SETGET_FUNCS(dir_transid, struct btrfs_dir_item, transid, 64);
1216 static inline void btrfs_dir_item_key(struct extent_buffer *eb,
1217 struct btrfs_dir_item *item,
1218 struct btrfs_disk_key *key)
1220 read_eb_member(eb, item, struct btrfs_dir_item, location, key);
1223 static inline void btrfs_set_dir_item_key(struct extent_buffer *eb,
1224 struct btrfs_dir_item *item,
1225 struct btrfs_disk_key *key)
1227 write_eb_member(eb, item, struct btrfs_dir_item, location, key);
1230 /* struct btrfs_disk_key */
1231 BTRFS_SETGET_STACK_FUNCS(disk_key_objectid, struct btrfs_disk_key,
1232 objectid, 64);
1233 BTRFS_SETGET_STACK_FUNCS(disk_key_offset, struct btrfs_disk_key, offset, 64);
1234 BTRFS_SETGET_STACK_FUNCS(disk_key_type, struct btrfs_disk_key, type, 8);
1236 static inline void btrfs_disk_key_to_cpu(struct btrfs_key *cpu,
1237 struct btrfs_disk_key *disk)
1239 cpu->offset = le64_to_cpu(disk->offset);
1240 cpu->type = disk->type;
1241 cpu->objectid = le64_to_cpu(disk->objectid);
1244 static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk,
1245 struct btrfs_key *cpu)
1247 disk->offset = cpu_to_le64(cpu->offset);
1248 disk->type = cpu->type;
1249 disk->objectid = cpu_to_le64(cpu->objectid);
1252 static inline void btrfs_node_key_to_cpu(struct extent_buffer *eb,
1253 struct btrfs_key *key, int nr)
1255 struct btrfs_disk_key disk_key;
1256 btrfs_node_key(eb, &disk_key, nr);
1257 btrfs_disk_key_to_cpu(key, &disk_key);
1260 static inline void btrfs_item_key_to_cpu(struct extent_buffer *eb,
1261 struct btrfs_key *key, int nr)
1263 struct btrfs_disk_key disk_key;
1264 btrfs_item_key(eb, &disk_key, nr);
1265 btrfs_disk_key_to_cpu(key, &disk_key);
1268 static inline void btrfs_dir_item_key_to_cpu(struct extent_buffer *eb,
1269 struct btrfs_dir_item *item,
1270 struct btrfs_key *key)
1272 struct btrfs_disk_key disk_key;
1273 btrfs_dir_item_key(eb, item, &disk_key);
1274 btrfs_disk_key_to_cpu(key, &disk_key);
1278 static inline u8 btrfs_key_type(struct btrfs_key *key)
1280 return key->type;
1283 static inline void btrfs_set_key_type(struct btrfs_key *key, u8 val)
1285 key->type = val;
1288 /* struct btrfs_header */
1289 BTRFS_SETGET_HEADER_FUNCS(header_bytenr, struct btrfs_header, bytenr, 64);
1290 BTRFS_SETGET_HEADER_FUNCS(header_generation, struct btrfs_header,
1291 generation, 64);
1292 BTRFS_SETGET_HEADER_FUNCS(header_owner, struct btrfs_header, owner, 64);
1293 BTRFS_SETGET_HEADER_FUNCS(header_nritems, struct btrfs_header, nritems, 32);
1294 BTRFS_SETGET_HEADER_FUNCS(header_flags, struct btrfs_header, flags, 64);
1295 BTRFS_SETGET_HEADER_FUNCS(header_level, struct btrfs_header, level, 8);
1297 static inline int btrfs_header_flag(struct extent_buffer *eb, u64 flag)
1299 return (btrfs_header_flags(eb) & flag) == flag;
1302 static inline int btrfs_set_header_flag(struct extent_buffer *eb, u64 flag)
1304 u64 flags = btrfs_header_flags(eb);
1305 btrfs_set_header_flags(eb, flags | flag);
1306 return (flags & flag) == flag;
1309 static inline int btrfs_clear_header_flag(struct extent_buffer *eb, u64 flag)
1311 u64 flags = btrfs_header_flags(eb);
1312 btrfs_set_header_flags(eb, flags & ~flag);
1313 return (flags & flag) == flag;
1316 static inline u8 *btrfs_header_fsid(struct extent_buffer *eb)
1318 unsigned long ptr = offsetof(struct btrfs_header, fsid);
1319 return (u8 *)ptr;
1322 static inline u8 *btrfs_header_chunk_tree_uuid(struct extent_buffer *eb)
1324 unsigned long ptr = offsetof(struct btrfs_header, chunk_tree_uuid);
1325 return (u8 *)ptr;
1328 static inline u8 *btrfs_super_fsid(struct extent_buffer *eb)
1330 unsigned long ptr = offsetof(struct btrfs_super_block, fsid);
1331 return (u8 *)ptr;
1334 static inline u8 *btrfs_header_csum(struct extent_buffer *eb)
1336 unsigned long ptr = offsetof(struct btrfs_header, csum);
1337 return (u8 *)ptr;
1340 static inline struct btrfs_node *btrfs_buffer_node(struct extent_buffer *eb)
1342 return NULL;
1345 static inline struct btrfs_leaf *btrfs_buffer_leaf(struct extent_buffer *eb)
1347 return NULL;
1350 static inline struct btrfs_header *btrfs_buffer_header(struct extent_buffer *eb)
1352 return NULL;
1355 static inline int btrfs_is_leaf(struct extent_buffer *eb)
1357 return (btrfs_header_level(eb) == 0);
1360 /* struct btrfs_root_item */
1361 BTRFS_SETGET_FUNCS(disk_root_generation, struct btrfs_root_item,
1362 generation, 64);
1363 BTRFS_SETGET_FUNCS(disk_root_refs, struct btrfs_root_item, refs, 32);
1364 BTRFS_SETGET_FUNCS(disk_root_bytenr, struct btrfs_root_item, bytenr, 64);
1365 BTRFS_SETGET_FUNCS(disk_root_level, struct btrfs_root_item, level, 8);
1367 BTRFS_SETGET_STACK_FUNCS(root_generation, struct btrfs_root_item,
1368 generation, 64);
1369 BTRFS_SETGET_STACK_FUNCS(root_bytenr, struct btrfs_root_item, bytenr, 64);
1370 BTRFS_SETGET_STACK_FUNCS(root_level, struct btrfs_root_item, level, 8);
1371 BTRFS_SETGET_STACK_FUNCS(root_dirid, struct btrfs_root_item, root_dirid, 64);
1372 BTRFS_SETGET_STACK_FUNCS(root_refs, struct btrfs_root_item, refs, 32);
1373 BTRFS_SETGET_STACK_FUNCS(root_flags, struct btrfs_root_item, flags, 64);
1374 BTRFS_SETGET_STACK_FUNCS(root_used, struct btrfs_root_item, bytes_used, 64);
1375 BTRFS_SETGET_STACK_FUNCS(root_limit, struct btrfs_root_item, byte_limit, 64);
1376 BTRFS_SETGET_STACK_FUNCS(root_last_snapshot, struct btrfs_root_item,
1377 last_snapshot, 64);
1380 /* struct btrfs_super_block */
1382 BTRFS_SETGET_STACK_FUNCS(super_bytenr, struct btrfs_super_block, bytenr, 64);
1383 BTRFS_SETGET_STACK_FUNCS(super_flags, struct btrfs_super_block, flags, 64);
1384 BTRFS_SETGET_STACK_FUNCS(super_generation, struct btrfs_super_block,
1385 generation, 64);
1386 BTRFS_SETGET_STACK_FUNCS(super_root, struct btrfs_super_block, root, 64);
1387 BTRFS_SETGET_STACK_FUNCS(super_sys_array_size,
1388 struct btrfs_super_block, sys_chunk_array_size, 32);
1389 BTRFS_SETGET_STACK_FUNCS(super_chunk_root_generation,
1390 struct btrfs_super_block, chunk_root_generation, 64);
1391 BTRFS_SETGET_STACK_FUNCS(super_root_level, struct btrfs_super_block,
1392 root_level, 8);
1393 BTRFS_SETGET_STACK_FUNCS(super_chunk_root, struct btrfs_super_block,
1394 chunk_root, 64);
1395 BTRFS_SETGET_STACK_FUNCS(super_chunk_root_level, struct btrfs_super_block,
1396 chunk_root_level, 8);
1397 BTRFS_SETGET_STACK_FUNCS(super_log_root, struct btrfs_super_block,
1398 log_root, 64);
1399 BTRFS_SETGET_STACK_FUNCS(super_log_root_transid, struct btrfs_super_block,
1400 log_root_transid, 64);
1401 BTRFS_SETGET_STACK_FUNCS(super_log_root_level, struct btrfs_super_block,
1402 log_root_level, 8);
1403 BTRFS_SETGET_STACK_FUNCS(super_total_bytes, struct btrfs_super_block,
1404 total_bytes, 64);
1405 BTRFS_SETGET_STACK_FUNCS(super_bytes_used, struct btrfs_super_block,
1406 bytes_used, 64);
1407 BTRFS_SETGET_STACK_FUNCS(super_sectorsize, struct btrfs_super_block,
1408 sectorsize, 32);
1409 BTRFS_SETGET_STACK_FUNCS(super_nodesize, struct btrfs_super_block,
1410 nodesize, 32);
1411 BTRFS_SETGET_STACK_FUNCS(super_leafsize, struct btrfs_super_block,
1412 leafsize, 32);
1413 BTRFS_SETGET_STACK_FUNCS(super_stripesize, struct btrfs_super_block,
1414 stripesize, 32);
1415 BTRFS_SETGET_STACK_FUNCS(super_root_dir, struct btrfs_super_block,
1416 root_dir_objectid, 64);
1417 BTRFS_SETGET_STACK_FUNCS(super_num_devices, struct btrfs_super_block,
1418 num_devices, 64);
1419 BTRFS_SETGET_STACK_FUNCS(super_compat_flags, struct btrfs_super_block,
1420 compat_flags, 64);
1421 BTRFS_SETGET_STACK_FUNCS(super_compat_ro_flags, struct btrfs_super_block,
1422 compat_flags, 64);
1423 BTRFS_SETGET_STACK_FUNCS(super_incompat_flags, struct btrfs_super_block,
1424 incompat_flags, 64);
1425 BTRFS_SETGET_STACK_FUNCS(super_csum_type, struct btrfs_super_block,
1426 csum_type, 16);
1428 static inline int btrfs_super_csum_size(struct btrfs_super_block *s)
1430 int t = btrfs_super_csum_type(s);
1431 BUG_ON(t >= ARRAY_SIZE(btrfs_csum_sizes));
1432 return btrfs_csum_sizes[t];
1435 static inline unsigned long btrfs_leaf_data(struct extent_buffer *l)
1437 return offsetof(struct btrfs_leaf, items);
1440 /* struct btrfs_file_extent_item */
1441 BTRFS_SETGET_FUNCS(file_extent_type, struct btrfs_file_extent_item, type, 8);
1443 static inline unsigned long btrfs_file_extent_inline_start(struct
1444 btrfs_file_extent_item *e)
1446 unsigned long offset = (unsigned long)e;
1447 offset += offsetof(struct btrfs_file_extent_item, disk_bytenr);
1448 return offset;
1451 static inline u32 btrfs_file_extent_calc_inline_size(u32 datasize)
1453 return offsetof(struct btrfs_file_extent_item, disk_bytenr) + datasize;
1456 BTRFS_SETGET_FUNCS(file_extent_disk_bytenr, struct btrfs_file_extent_item,
1457 disk_bytenr, 64);
1458 BTRFS_SETGET_FUNCS(file_extent_generation, struct btrfs_file_extent_item,
1459 generation, 64);
1460 BTRFS_SETGET_FUNCS(file_extent_disk_num_bytes, struct btrfs_file_extent_item,
1461 disk_num_bytes, 64);
1462 BTRFS_SETGET_FUNCS(file_extent_offset, struct btrfs_file_extent_item,
1463 offset, 64);
1464 BTRFS_SETGET_FUNCS(file_extent_num_bytes, struct btrfs_file_extent_item,
1465 num_bytes, 64);
1466 BTRFS_SETGET_FUNCS(file_extent_ram_bytes, struct btrfs_file_extent_item,
1467 ram_bytes, 64);
1468 BTRFS_SETGET_FUNCS(file_extent_compression, struct btrfs_file_extent_item,
1469 compression, 8);
1470 BTRFS_SETGET_FUNCS(file_extent_encryption, struct btrfs_file_extent_item,
1471 encryption, 8);
1472 BTRFS_SETGET_FUNCS(file_extent_other_encoding, struct btrfs_file_extent_item,
1473 other_encoding, 16);
1475 /* this returns the number of file bytes represented by the inline item.
1476 * If an item is compressed, this is the uncompressed size
1478 static inline u32 btrfs_file_extent_inline_len(struct extent_buffer *eb,
1479 struct btrfs_file_extent_item *e)
1481 return btrfs_file_extent_ram_bytes(eb, e);
1485 * this returns the number of bytes used by the item on disk, minus the
1486 * size of any extent headers. If a file is compressed on disk, this is
1487 * the compressed size
1489 static inline u32 btrfs_file_extent_inline_item_len(struct extent_buffer *eb,
1490 struct btrfs_item *e)
1492 unsigned long offset;
1493 offset = offsetof(struct btrfs_file_extent_item, disk_bytenr);
1494 return btrfs_item_size(eb, e) - offset;
1497 static inline u32 btrfs_level_size(struct btrfs_root *root, int level) {
1498 if (level == 0)
1499 return root->leafsize;
1500 return root->nodesize;
1503 /* helper function to cast into the data area of the leaf. */
1504 #define btrfs_item_ptr(leaf, slot, type) \
1505 ((type *)(btrfs_leaf_data(leaf) + \
1506 btrfs_item_offset_nr(leaf, slot)))
1508 #define btrfs_item_ptr_offset(leaf, slot) \
1509 ((unsigned long)(btrfs_leaf_data(leaf) + \
1510 btrfs_item_offset_nr(leaf, slot)))
1512 /* extent-tree.c */
1513 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
1514 struct btrfs_root *root);
1515 int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy);
1516 struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
1517 btrfs_fs_info *info,
1518 u64 bytenr);
1519 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
1520 struct btrfs_block_group_cache
1521 *hint, u64 search_start,
1522 int data, int owner);
1523 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
1524 struct btrfs_root *root,
1525 u32 blocksize, u64 parent,
1526 u64 root_objectid,
1527 u64 ref_generation,
1528 int level,
1529 u64 hint,
1530 u64 empty_size);
1531 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
1532 struct btrfs_root *root,
1533 u64 num_bytes, u64 parent,
1534 u64 root_objectid, u64 ref_generation,
1535 u64 owner, u64 empty_size, u64 hint_byte,
1536 u64 search_end, struct btrfs_key *ins, int data);
1537 int btrfs_lookup_extent_ref(struct btrfs_trans_handle *trans,
1538 struct btrfs_root *root, u64 bytenr,
1539 u64 num_bytes, u32 *refs);
1540 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1541 struct extent_buffer *orig_buf, struct extent_buffer *buf,
1542 u32 *nr_extents);
1543 int btrfs_update_ref(struct btrfs_trans_handle *trans,
1544 struct btrfs_root *root, struct extent_buffer *orig_buf,
1545 struct extent_buffer *buf, int start_slot, int nr);
1546 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
1547 *root, u64 bytenr, u64 num_bytes, u64 parent,
1548 u64 root_objectid, u64 ref_generation,
1549 u64 owner_objectid, int pin);
1550 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
1551 struct btrfs_root *root,
1552 struct extent_io_tree *unpin);
1553 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1554 struct btrfs_root *root,
1555 u64 bytenr, u64 num_bytes, u64 parent,
1556 u64 root_objectid, u64 ref_generation,
1557 u64 owner_objectid);
1558 int btrfs_update_extent_ref(struct btrfs_trans_handle *trans,
1559 struct btrfs_root *root, u64 bytenr,
1560 u64 orig_parent, u64 parent,
1561 u64 root_objectid, u64 ref_generation,
1562 u64 owner_objectid);
1563 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
1564 struct btrfs_root *root);
1565 int btrfs_free_block_groups(struct btrfs_fs_info *info);
1566 int btrfs_read_block_groups(struct btrfs_root *root);
1567 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
1568 struct btrfs_root *root, u64 bytes_used,
1569 u64 type, u64 chunk_objectid, u64 chunk_offset,
1570 u64 size);
1571 int btrfs_make_block_groups(struct btrfs_trans_handle *trans,
1572 struct btrfs_root *root);
1573 int btrfs_update_block_group(struct btrfs_trans_handle *trans,
1574 struct btrfs_root *root, u64 bytenr, u64 num,
1575 int alloc, int mark_free);
1576 /* ctree.c */
1577 int btrfs_previous_item(struct btrfs_root *root,
1578 struct btrfs_path *path, u64 min_objectid,
1579 int type);
1580 int btrfs_comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2);
1581 int btrfs_cow_block(struct btrfs_trans_handle *trans,
1582 struct btrfs_root *root, struct extent_buffer *buf,
1583 struct extent_buffer *parent, int parent_slot,
1584 struct extent_buffer **cow_ret);
1585 int __btrfs_cow_block(struct btrfs_trans_handle *trans,
1586 struct btrfs_root *root,
1587 struct extent_buffer *buf,
1588 struct extent_buffer *parent, int parent_slot,
1589 struct extent_buffer **cow_ret,
1590 u64 search_start, u64 empty_size);
1591 int btrfs_copy_root(struct btrfs_trans_handle *trans,
1592 struct btrfs_root *root,
1593 struct extent_buffer *buf,
1594 struct extent_buffer **cow_ret, u64 new_root_objectid);
1595 int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root
1596 *root, struct btrfs_path *path, u32 data_size);
1597 int btrfs_truncate_item(struct btrfs_trans_handle *trans,
1598 struct btrfs_root *root,
1599 struct btrfs_path *path,
1600 u32 new_size, int from_end);
1601 int btrfs_split_item(struct btrfs_trans_handle *trans,
1602 struct btrfs_root *root,
1603 struct btrfs_path *path,
1604 struct btrfs_key *new_key,
1605 unsigned long split_offset);
1606 int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
1607 *root, struct btrfs_key *key, struct btrfs_path *p, int
1608 ins_len, int cow);
1609 int btrfs_realloc_node(struct btrfs_trans_handle *trans,
1610 struct btrfs_root *root, struct extent_buffer *parent,
1611 int start_slot, int cache_only, u64 *last_ret,
1612 struct btrfs_key *progress);
1613 void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
1614 struct btrfs_path *btrfs_alloc_path(void);
1615 void btrfs_free_path(struct btrfs_path *p);
1616 void btrfs_init_path(struct btrfs_path *p);
1617 int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1618 struct btrfs_path *path, int slot, int nr);
1620 static inline int btrfs_del_item(struct btrfs_trans_handle *trans,
1621 struct btrfs_root *root,
1622 struct btrfs_path *path)
1624 return btrfs_del_items(trans, root, path, path->slots[0], 1);
1627 int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
1628 *root, struct btrfs_key *key, void *data, u32 data_size);
1629 int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
1630 struct btrfs_root *root,
1631 struct btrfs_path *path,
1632 struct btrfs_key *cpu_key, u32 *data_size, int nr);
1634 static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
1635 struct btrfs_root *root,
1636 struct btrfs_path *path,
1637 struct btrfs_key *key,
1638 u32 data_size)
1640 return btrfs_insert_empty_items(trans, root, path, key, &data_size, 1);
1643 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
1644 int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path);
1645 int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf);
1646 int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
1647 *root);
1648 int btrfs_set_item_key_safe(struct btrfs_trans_handle *trans,
1649 struct btrfs_root *root, struct btrfs_path *path,
1650 struct btrfs_key *new_key);
1652 /* root-item.c */
1653 int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
1654 struct btrfs_root *tree_root,
1655 u64 root_id, u8 type, u64 ref_id,
1656 u64 dirid, u64 sequence,
1657 const char *name, int name_len);
1658 int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1659 struct btrfs_key *key);
1660 int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root
1661 *root, struct btrfs_key *key, struct btrfs_root_item
1662 *item);
1663 int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
1664 *root, struct btrfs_key *key, struct btrfs_root_item
1665 *item);
1666 int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct
1667 btrfs_root_item *item, struct btrfs_key *key);
1668 int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid,
1669 struct btrfs_root *latest_root);
1670 /* dir-item.c */
1671 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
1672 *root, const char *name, int name_len, u64 dir,
1673 struct btrfs_key *location, u8 type, u64 index);
1674 struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
1675 struct btrfs_root *root,
1676 struct btrfs_path *path, u64 dir,
1677 const char *name, int name_len,
1678 int mod);
1679 struct btrfs_dir_item *
1680 btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
1681 struct btrfs_root *root,
1682 struct btrfs_path *path, u64 dir,
1683 u64 objectid, const char *name, int name_len,
1684 int mod);
1685 struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root,
1686 struct btrfs_path *path,
1687 const char *name, int name_len);
1688 int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
1689 struct btrfs_root *root,
1690 struct btrfs_path *path,
1691 struct btrfs_dir_item *di);
1692 int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
1693 struct btrfs_root *root, const char *name,
1694 u16 name_len, const void *data, u16 data_len,
1695 u64 dir);
1696 struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
1697 struct btrfs_root *root,
1698 struct btrfs_path *path, u64 dir,
1699 const char *name, u16 name_len,
1700 int mod);
1701 /* inode-map.c */
1702 int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
1703 struct btrfs_root *fs_root,
1704 u64 dirid, u64 *objectid);
1705 int btrfs_find_highest_inode(struct btrfs_root *fs_root, u64 *objectid);
1707 /* inode-item.c */
1708 int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
1709 struct btrfs_root *root,
1710 const char *name, int name_len,
1711 u64 inode_objectid, u64 ref_objectid, u64 index);
1712 int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
1713 struct btrfs_root *root,
1714 const char *name, int name_len,
1715 u64 inode_objectid, u64 ref_objectid);
1716 int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
1717 struct btrfs_root *root,
1718 struct btrfs_path *path, u64 objectid);
1719 int btrfs_insert_inode(struct btrfs_trans_handle *trans, struct btrfs_root
1720 *root, u64 objectid, struct btrfs_inode_item
1721 *inode_item);
1722 int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
1723 *root, struct btrfs_path *path,
1724 struct btrfs_key *location, int mod);
1726 /* file-item.c */
1727 int btrfs_del_csums(struct btrfs_trans_handle *trans,
1728 struct btrfs_root *root, u64 bytenr, u64 len);
1729 int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
1730 struct btrfs_root *root,
1731 u64 objectid, u64 pos, u64 offset,
1732 u64 disk_num_bytes,
1733 u64 num_bytes);
1734 int btrfs_insert_inline_extent(struct btrfs_trans_handle *trans,
1735 struct btrfs_root *root, u64 objectid,
1736 u64 offset, char *buffer, size_t size);
1737 int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
1738 struct btrfs_root *root,
1739 struct btrfs_path *path, u64 objectid,
1740 u64 bytenr, int mod);
1741 int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
1742 struct btrfs_root *root, u64 alloc_end,
1743 u64 bytenr, char *data, size_t len);
1744 struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
1745 struct btrfs_root *root,
1746 struct btrfs_path *path,
1747 u64 bytenr, int cow);
1748 int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
1749 struct btrfs_root *root, struct btrfs_path *path,
1750 u64 isize);
1751 #endif