xref: /openbmc/linux/fs/btrfs/ctree.h (revision 9f5fae2fe6dc35b46bf56183f11398451851cb3f)
1 #ifndef __BTRFS__
2 #define __BTRFS__
3 
4 #include "list.h"
5 #include "kerncompat.h"
6 
7 struct btrfs_trans_handle;
8 
9 #define BTRFS_MAGIC "_BtRfS_M"
10 
11 #define BTRFS_ROOT_TREE_OBJECTID 1
12 #define BTRFS_EXTENT_TREE_OBJECTID 2
13 #define BTRFS_INODE_MAP_OBJECTID 3
14 #define BTRFS_FS_TREE_OBJECTID 4
15 
16 /*
17  * the key defines the order in the tree, and so it also defines (optimal)
18  * block layout.  objectid corresonds to the inode number.  The flags
19  * tells us things about the object, and is a kind of stream selector.
20  * so for a given inode, keys with flags of 1 might refer to the inode
21  * data, flags of 2 may point to file data in the btree and flags == 3
22  * may point to extents.
23  *
24  * offset is the starting byte offset for this key in the stream.
25  *
26  * btrfs_disk_key is in disk byte order.  struct btrfs_key is always
27  * in cpu native order.  Otherwise they are identical and their sizes
28  * should be the same (ie both packed)
29  */
30 struct btrfs_disk_key {
31 	__le64 objectid;
32 	__le32 flags;
33 	__le64 offset;
34 } __attribute__ ((__packed__));
35 
36 struct btrfs_key {
37 	u64 objectid;
38 	u32 flags;
39 	u64 offset;
40 } __attribute__ ((__packed__));
41 
42 /*
43  * every tree block (leaf or node) starts with this header.
44  */
45 struct btrfs_header {
46 	u8 fsid[16]; /* FS specific uuid */
47 	__le64 blocknr; /* which block this node is supposed to live in */
48 	__le64 parentid; /* objectid of the tree root */
49 	__le32 csum;
50 	__le32 ham;
51 	__le16 nritems;
52 	__le16 flags;
53 	/* generation flags to be added */
54 } __attribute__ ((__packed__));
55 
56 #define BTRFS_MAX_LEVEL 8
57 #define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->blocksize - \
58 			        sizeof(struct btrfs_header)) / \
59 			       (sizeof(struct btrfs_disk_key) + sizeof(u64)))
60 #define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
61 #define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->blocksize))
62 
63 struct btrfs_buffer;
64 /*
65  * the super block basically lists the main trees of the FS
66  * it currently lacks any block count etc etc
67  */
68 struct btrfs_super_block {
69 	u8 fsid[16];    /* FS specific uuid */
70 	__le64 blocknr; /* this block number */
71 	__le32 csum;
72 	__le64 magic;
73 	__le32 blocksize;
74 	__le64 generation;
75 	__le64 root;
76 	__le64 total_blocks;
77 	__le64 blocks_used;
78 } __attribute__ ((__packed__));
79 
80 /*
81  * A leaf is full of items. offset and size tell us where to find
82  * the item in the leaf (relative to the start of the data area)
83  */
84 struct btrfs_item {
85 	struct btrfs_disk_key key;
86 	__le32 offset;
87 	__le16 size;
88 } __attribute__ ((__packed__));
89 
90 /*
91  * leaves have an item area and a data area:
92  * [item0, item1....itemN] [free space] [dataN...data1, data0]
93  *
94  * The data is separate from the items to get the keys closer together
95  * during searches.
96  */
97 struct btrfs_leaf {
98 	struct btrfs_header header;
99 	struct btrfs_item items[];
100 } __attribute__ ((__packed__));
101 
102 /*
103  * all non-leaf blocks are nodes, they hold only keys and pointers to
104  * other blocks
105  */
106 struct btrfs_key_ptr {
107 	struct btrfs_disk_key key;
108 	__le64 blockptr;
109 } __attribute__ ((__packed__));
110 
111 struct btrfs_node {
112 	struct btrfs_header header;
113 	struct btrfs_key_ptr ptrs[];
114 } __attribute__ ((__packed__));
115 
116 /*
117  * btrfs_paths remember the path taken from the root down to the leaf.
118  * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point
119  * to any other levels that are present.
120  *
121  * The slots array records the index of the item or block pointer
122  * used while walking the tree.
123  */
124 struct btrfs_path {
125 	struct btrfs_buffer *nodes[BTRFS_MAX_LEVEL];
126 	int slots[BTRFS_MAX_LEVEL];
127 };
128 
129 /*
130  * items in the extent btree are used to record the objectid of the
131  * owner of the block and the number of references
132  */
133 struct btrfs_extent_item {
134 	__le32 refs;
135 	__le64 owner;
136 } __attribute__ ((__packed__));
137 
138 struct btrfs_inode_timespec {
139 	__le32 sec;
140 	__le32 nsec;
141 } __attribute__ ((__packed__));
142 
143 /*
144  * there is no padding here on purpose.  If you want to extent the inode,
145  * make a new item type
146  */
147 struct btrfs_inode_item {
148 	__le64 generation;
149 	__le64 size;
150 	__le64 nblocks;
151 	__le32 nlink;
152 	__le32 uid;
153 	__le32 gid;
154 	__le32 mode;
155 	__le32 rdev;
156 	__le16 flags;
157 	__le16 compat_flags;
158 	struct btrfs_inode_timespec atime;
159 	struct btrfs_inode_timespec ctime;
160 	struct btrfs_inode_timespec mtime;
161 	struct btrfs_inode_timespec otime;
162 } __attribute__ ((__packed__));
163 
164 /* inline data is just a blob of bytes */
165 struct btrfs_inline_data_item {
166 	u8 data;
167 } __attribute__ ((__packed__));
168 
169 struct btrfs_dir_item {
170 	__le64 objectid;
171 	__le16 flags;
172 	__le16 name_len;
173 	u8 type;
174 } __attribute__ ((__packed__));
175 
176 struct btrfs_root_item {
177 	__le64 blocknr;
178 	__le32 flags;
179 	__le64 block_limit;
180 	__le64 blocks_used;
181 	__le32 refs;
182 } __attribute__ ((__packed__));
183 
184 struct btrfs_file_extent_item {
185 	/*
186 	 * disk space consumed by the extent, checksum blocks are included
187 	 * in these numbers
188 	 */
189 	__le64 disk_blocknr;
190 	__le64 disk_num_blocks;
191 	/*
192 	 * the logical offset in file bytes (no csums)
193 	 * this extent record is for.  This allows a file extent to point
194 	 * into the middle of an existing extent on disk, sharing it
195 	 * between two snapshots (useful if some bytes in the middle of the
196 	 * extent have changed
197 	 */
198 	__le64 offset;
199 	/*
200 	 * the logical number of file blocks (no csums included)
201 	 */
202 	__le64 num_blocks;
203 } __attribute__ ((__packed__));
204 
205 struct btrfs_inode_map_item {
206 	struct btrfs_disk_key key;
207 } __attribute__ ((__packed__));
208 
209 struct btrfs_fs_info {
210 	struct btrfs_root *fs_root;
211 	struct btrfs_root *extent_root;
212 	struct btrfs_root *tree_root;
213 	struct btrfs_root *inode_root;
214 	struct btrfs_key current_insert;
215 	struct btrfs_key last_insert;
216 	struct radix_tree_root cache_radix;
217 	struct radix_tree_root pinned_radix;
218 	struct list_head trans;
219 	struct list_head cache;
220 	u64 last_inode_alloc;
221 	u64 last_inode_alloc_dirid;
222 	int cache_size;
223 	int fp;
224 	struct btrfs_trans_handle *running_transaction;
225 };
226 
227 /*
228  * in ram representation of the tree.  extent_root is used for all allocations
229  * and for the extent tree extent_root root.  current_insert is used
230  * only for the extent tree.
231  */
232 struct btrfs_root {
233 	struct btrfs_buffer *node;
234 	struct btrfs_buffer *commit_root;
235 	struct btrfs_root_item root_item;
236 	struct btrfs_key root_key;
237 	struct btrfs_fs_info *fs_info;
238 	u32 blocksize;
239 	int ref_cows;
240 	u32 type;
241 };
242 
243 /* the lower bits in the key flags defines the item type */
244 #define BTRFS_KEY_TYPE_MAX	256
245 #define BTRFS_KEY_TYPE_MASK	(BTRFS_KEY_TYPE_MAX - 1)
246 
247 /*
248  * inode items have the data typically returned from stat and store other
249  * info about object characteristics.  There is one for every file and dir in
250  * the FS
251  */
252 #define BTRFS_INODE_ITEM_KEY	1
253 
254 /*
255  * dir items are the name -> inode pointers in a directory.  There is one
256  * for every name in a directory.
257  */
258 #define BTRFS_DIR_ITEM_KEY	2
259 /*
260  * inline data is file data that fits in the btree.
261  */
262 #define BTRFS_INLINE_DATA_KEY	3
263 /*
264  * extent data is for data that can't fit in the btree.  It points to
265  * a (hopefully) huge chunk of disk
266  */
267 #define BTRFS_EXTENT_DATA_KEY	4
268 /*
269  * root items point to tree roots.  There are typically in the root
270  * tree used by the super block to find all the other trees
271  */
272 #define BTRFS_ROOT_ITEM_KEY	5
273 /*
274  * extent items are in the extent map tree.  These record which blocks
275  * are used, and how many references there are to each block
276  */
277 #define BTRFS_EXTENT_ITEM_KEY	6
278 
279 /*
280  * the inode map records which inode numbers are in use and where
281  * they actually live on disk
282  */
283 #define BTRFS_INODE_MAP_ITEM_KEY 7
284 /*
285  * string items are for debugging.  They just store a short string of
286  * data in the FS
287  */
288 #define BTRFS_STRING_ITEM_KEY	8
289 
290 static inline u64 btrfs_inode_generation(struct btrfs_inode_item *i)
291 {
292 	return le64_to_cpu(i->generation);
293 }
294 
295 static inline void btrfs_set_inode_generation(struct btrfs_inode_item *i,
296 					      u64 val)
297 {
298 	i->generation = cpu_to_le64(val);
299 }
300 
301 static inline u64 btrfs_inode_size(struct btrfs_inode_item *i)
302 {
303 	return le64_to_cpu(i->size);
304 }
305 
306 static inline void btrfs_set_inode_size(struct btrfs_inode_item *i, u64 val)
307 {
308 	i->size = cpu_to_le64(val);
309 }
310 
311 static inline u64 btrfs_inode_nblocks(struct btrfs_inode_item *i)
312 {
313 	return le64_to_cpu(i->nblocks);
314 }
315 
316 static inline void btrfs_set_inode_nblocks(struct btrfs_inode_item *i, u64 val)
317 {
318 	i->nblocks = cpu_to_le64(val);
319 }
320 
321 static inline u32 btrfs_inode_nlink(struct btrfs_inode_item *i)
322 {
323 	return le32_to_cpu(i->nlink);
324 }
325 
326 static inline void btrfs_set_inode_nlink(struct btrfs_inode_item *i, u32 val)
327 {
328 	i->nlink = cpu_to_le32(val);
329 }
330 
331 static inline u32 btrfs_inode_uid(struct btrfs_inode_item *i)
332 {
333 	return le32_to_cpu(i->uid);
334 }
335 
336 static inline void btrfs_set_inode_uid(struct btrfs_inode_item *i, u32 val)
337 {
338 	i->uid = cpu_to_le32(val);
339 }
340 
341 static inline u32 btrfs_inode_gid(struct btrfs_inode_item *i)
342 {
343 	return le32_to_cpu(i->gid);
344 }
345 
346 static inline void btrfs_set_inode_gid(struct btrfs_inode_item *i, u32 val)
347 {
348 	i->gid = cpu_to_le32(val);
349 }
350 
351 static inline u32 btrfs_inode_mode(struct btrfs_inode_item *i)
352 {
353 	return le32_to_cpu(i->mode);
354 }
355 
356 static inline void btrfs_set_inode_mode(struct btrfs_inode_item *i, u32 val)
357 {
358 	i->mode = cpu_to_le32(val);
359 }
360 
361 static inline u32 btrfs_inode_rdev(struct btrfs_inode_item *i)
362 {
363 	return le32_to_cpu(i->rdev);
364 }
365 
366 static inline void btrfs_set_inode_rdev(struct btrfs_inode_item *i, u32 val)
367 {
368 	i->rdev = cpu_to_le32(val);
369 }
370 
371 static inline u16 btrfs_inode_flags(struct btrfs_inode_item *i)
372 {
373 	return le16_to_cpu(i->flags);
374 }
375 
376 static inline void btrfs_set_inode_flags(struct btrfs_inode_item *i, u16 val)
377 {
378 	i->flags = cpu_to_le16(val);
379 }
380 
381 static inline u16 btrfs_inode_compat_flags(struct btrfs_inode_item *i)
382 {
383 	return le16_to_cpu(i->compat_flags);
384 }
385 
386 static inline void btrfs_set_inode_compat_flags(struct btrfs_inode_item *i,
387 						u16 val)
388 {
389 	i->compat_flags = cpu_to_le16(val);
390 }
391 
392 
393 static inline u64 btrfs_extent_owner(struct btrfs_extent_item *ei)
394 {
395 	return le64_to_cpu(ei->owner);
396 }
397 
398 static inline void btrfs_set_extent_owner(struct btrfs_extent_item *ei, u64 val)
399 {
400 	ei->owner = cpu_to_le64(val);
401 }
402 
403 static inline u32 btrfs_extent_refs(struct btrfs_extent_item *ei)
404 {
405 	return le32_to_cpu(ei->refs);
406 }
407 
408 static inline void btrfs_set_extent_refs(struct btrfs_extent_item *ei, u32 val)
409 {
410 	ei->refs = cpu_to_le32(val);
411 }
412 
413 static inline u64 btrfs_node_blockptr(struct btrfs_node *n, int nr)
414 {
415 	return le64_to_cpu(n->ptrs[nr].blockptr);
416 }
417 
418 static inline void btrfs_set_node_blockptr(struct btrfs_node *n, int nr,
419 					   u64 val)
420 {
421 	n->ptrs[nr].blockptr = cpu_to_le64(val);
422 }
423 
424 static inline u32 btrfs_item_offset(struct btrfs_item *item)
425 {
426 	return le32_to_cpu(item->offset);
427 }
428 
429 static inline void btrfs_set_item_offset(struct btrfs_item *item, u32 val)
430 {
431 	item->offset = cpu_to_le32(val);
432 }
433 
434 static inline u32 btrfs_item_end(struct btrfs_item *item)
435 {
436 	return le32_to_cpu(item->offset) + le16_to_cpu(item->size);
437 }
438 
439 static inline u16 btrfs_item_size(struct btrfs_item *item)
440 {
441 	return le16_to_cpu(item->size);
442 }
443 
444 static inline void btrfs_set_item_size(struct btrfs_item *item, u16 val)
445 {
446 	item->size = cpu_to_le16(val);
447 }
448 
449 static inline u64 btrfs_dir_objectid(struct btrfs_dir_item *d)
450 {
451 	return le64_to_cpu(d->objectid);
452 }
453 
454 static inline void btrfs_set_dir_objectid(struct btrfs_dir_item *d, u64 val)
455 {
456 	d->objectid = cpu_to_le64(val);
457 }
458 
459 static inline u16 btrfs_dir_flags(struct btrfs_dir_item *d)
460 {
461 	return le16_to_cpu(d->flags);
462 }
463 
464 static inline void btrfs_set_dir_flags(struct btrfs_dir_item *d, u16 val)
465 {
466 	d->flags = cpu_to_le16(val);
467 }
468 
469 static inline u8 btrfs_dir_type(struct btrfs_dir_item *d)
470 {
471 	return d->type;
472 }
473 
474 static inline void btrfs_set_dir_type(struct btrfs_dir_item *d, u8 val)
475 {
476 	d->type = val;
477 }
478 
479 static inline u16 btrfs_dir_name_len(struct btrfs_dir_item *d)
480 {
481 	return le16_to_cpu(d->name_len);
482 }
483 
484 static inline void btrfs_set_dir_name_len(struct btrfs_dir_item *d, u16 val)
485 {
486 	d->name_len = cpu_to_le16(val);
487 }
488 
489 static inline void btrfs_disk_key_to_cpu(struct btrfs_key *cpu,
490 					 struct btrfs_disk_key *disk)
491 {
492 	cpu->offset = le64_to_cpu(disk->offset);
493 	cpu->flags = le32_to_cpu(disk->flags);
494 	cpu->objectid = le64_to_cpu(disk->objectid);
495 }
496 
497 static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk,
498 					 struct btrfs_key *cpu)
499 {
500 	disk->offset = cpu_to_le64(cpu->offset);
501 	disk->flags = cpu_to_le32(cpu->flags);
502 	disk->objectid = cpu_to_le64(cpu->objectid);
503 }
504 
505 static inline u64 btrfs_disk_key_objectid(struct btrfs_disk_key *disk)
506 {
507 	return le64_to_cpu(disk->objectid);
508 }
509 
510 static inline void btrfs_set_disk_key_objectid(struct btrfs_disk_key *disk,
511 					       u64 val)
512 {
513 	disk->objectid = cpu_to_le64(val);
514 }
515 
516 static inline u64 btrfs_disk_key_offset(struct btrfs_disk_key *disk)
517 {
518 	return le64_to_cpu(disk->offset);
519 }
520 
521 static inline void btrfs_set_disk_key_offset(struct btrfs_disk_key *disk,
522 					     u64 val)
523 {
524 	disk->offset = cpu_to_le64(val);
525 }
526 
527 static inline u32 btrfs_disk_key_flags(struct btrfs_disk_key *disk)
528 {
529 	return le32_to_cpu(disk->flags);
530 }
531 
532 static inline void btrfs_set_disk_key_flags(struct btrfs_disk_key *disk,
533 					    u32 val)
534 {
535 	disk->flags = cpu_to_le32(val);
536 }
537 
538 static inline u32 btrfs_key_type(struct btrfs_key *key)
539 {
540 	return key->flags & BTRFS_KEY_TYPE_MASK;
541 }
542 
543 static inline u32 btrfs_disk_key_type(struct btrfs_disk_key *key)
544 {
545 	return le32_to_cpu(key->flags) & BTRFS_KEY_TYPE_MASK;
546 }
547 
548 static inline void btrfs_set_key_type(struct btrfs_key *key, u32 type)
549 {
550 	BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
551 	key->flags = (key->flags & ~((u64)BTRFS_KEY_TYPE_MASK)) | type;
552 }
553 
554 static inline void btrfs_set_disk_key_type(struct btrfs_disk_key *key, u32 type)
555 {
556 	u32 flags = btrfs_disk_key_flags(key);
557 	BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
558 	flags = (flags & ~((u64)BTRFS_KEY_TYPE_MASK)) | type;
559 	btrfs_set_disk_key_flags(key, flags);
560 }
561 
562 static inline u64 btrfs_header_blocknr(struct btrfs_header *h)
563 {
564 	return le64_to_cpu(h->blocknr);
565 }
566 
567 static inline void btrfs_set_header_blocknr(struct btrfs_header *h, u64 blocknr)
568 {
569 	h->blocknr = cpu_to_le64(blocknr);
570 }
571 
572 static inline u64 btrfs_header_parentid(struct btrfs_header *h)
573 {
574 	return le64_to_cpu(h->parentid);
575 }
576 
577 static inline void btrfs_set_header_parentid(struct btrfs_header *h,
578 					     u64 parentid)
579 {
580 	h->parentid = cpu_to_le64(parentid);
581 }
582 
583 static inline u16 btrfs_header_nritems(struct btrfs_header *h)
584 {
585 	return le16_to_cpu(h->nritems);
586 }
587 
588 static inline void btrfs_set_header_nritems(struct btrfs_header *h, u16 val)
589 {
590 	h->nritems = cpu_to_le16(val);
591 }
592 
593 static inline u16 btrfs_header_flags(struct btrfs_header *h)
594 {
595 	return le16_to_cpu(h->flags);
596 }
597 
598 static inline void btrfs_set_header_flags(struct btrfs_header *h, u16 val)
599 {
600 	h->flags = cpu_to_le16(val);
601 }
602 
603 static inline int btrfs_header_level(struct btrfs_header *h)
604 {
605 	return btrfs_header_flags(h) & (BTRFS_MAX_LEVEL - 1);
606 }
607 
608 static inline void btrfs_set_header_level(struct btrfs_header *h, int level)
609 {
610 	u16 flags;
611 	BUG_ON(level > BTRFS_MAX_LEVEL);
612 	flags = btrfs_header_flags(h) & ~(BTRFS_MAX_LEVEL - 1);
613 	btrfs_set_header_flags(h, flags | level);
614 }
615 
616 static inline int btrfs_is_leaf(struct btrfs_node *n)
617 {
618 	return (btrfs_header_level(&n->header) == 0);
619 }
620 
621 static inline u64 btrfs_root_blocknr(struct btrfs_root_item *item)
622 {
623 	return le64_to_cpu(item->blocknr);
624 }
625 
626 static inline void btrfs_set_root_blocknr(struct btrfs_root_item *item, u64 val)
627 {
628 	item->blocknr = cpu_to_le64(val);
629 }
630 
631 static inline u32 btrfs_root_refs(struct btrfs_root_item *item)
632 {
633 	return le32_to_cpu(item->refs);
634 }
635 
636 static inline void btrfs_set_root_refs(struct btrfs_root_item *item, u32 val)
637 {
638 	item->refs = cpu_to_le32(val);
639 }
640 
641 static inline u64 btrfs_super_blocknr(struct btrfs_super_block *s)
642 {
643 	return le64_to_cpu(s->blocknr);
644 }
645 
646 static inline void btrfs_set_super_blocknr(struct btrfs_super_block *s, u64 val)
647 {
648 	s->blocknr = cpu_to_le64(val);
649 }
650 
651 static inline u64 btrfs_super_root(struct btrfs_super_block *s)
652 {
653 	return le64_to_cpu(s->root);
654 }
655 
656 static inline void btrfs_set_super_root(struct btrfs_super_block *s, u64 val)
657 {
658 	s->root = cpu_to_le64(val);
659 }
660 
661 static inline u64 btrfs_super_total_blocks(struct btrfs_super_block *s)
662 {
663 	return le64_to_cpu(s->total_blocks);
664 }
665 
666 static inline void btrfs_set_super_total_blocks(struct btrfs_super_block *s,
667 						u64 val)
668 {
669 	s->total_blocks = cpu_to_le64(val);
670 }
671 
672 static inline u64 btrfs_super_blocks_used(struct btrfs_super_block *s)
673 {
674 	return le64_to_cpu(s->blocks_used);
675 }
676 
677 static inline void btrfs_set_super_blocks_used(struct btrfs_super_block *s,
678 						u64 val)
679 {
680 	s->blocks_used = cpu_to_le64(val);
681 }
682 
683 static inline u32 btrfs_super_blocksize(struct btrfs_super_block *s)
684 {
685 	return le32_to_cpu(s->blocksize);
686 }
687 
688 static inline void btrfs_set_super_blocksize(struct btrfs_super_block *s,
689 						u32 val)
690 {
691 	s->blocksize = cpu_to_le32(val);
692 }
693 
694 static inline u8 *btrfs_leaf_data(struct btrfs_leaf *l)
695 {
696 	return (u8 *)l->items;
697 }
698 
699 static inline u64 btrfs_file_extent_disk_blocknr(struct btrfs_file_extent_item
700 						 *e)
701 {
702 	return le64_to_cpu(e->disk_blocknr);
703 }
704 
705 static inline void btrfs_set_file_extent_disk_blocknr(struct
706 						      btrfs_file_extent_item
707 						      *e, u64 val)
708 {
709 	e->disk_blocknr = cpu_to_le64(val);
710 }
711 
712 static inline u64 btrfs_file_extent_disk_num_blocks(struct
713 						    btrfs_file_extent_item *e)
714 {
715 	return le64_to_cpu(e->disk_num_blocks);
716 }
717 
718 static inline void btrfs_set_file_extent_disk_num_blocks(struct
719 							 btrfs_file_extent_item
720 							 *e, u64 val)
721 {
722 	e->disk_num_blocks = cpu_to_le64(val);
723 }
724 
725 static inline u64 btrfs_file_extent_offset(struct btrfs_file_extent_item *e)
726 {
727 	return le64_to_cpu(e->offset);
728 }
729 
730 static inline void btrfs_set_file_extent_offset(struct btrfs_file_extent_item
731 						*e, u64 val)
732 {
733 	e->offset = cpu_to_le64(val);
734 }
735 
736 static inline u64 btrfs_file_extent_num_blocks(struct btrfs_file_extent_item
737 					       *e)
738 {
739 	return le64_to_cpu(e->num_blocks);
740 }
741 
742 static inline void btrfs_set_file_extent_num_blocks(struct
743 						    btrfs_file_extent_item *e,
744 						    u64 val)
745 {
746 	e->num_blocks = cpu_to_le64(val);
747 }
748 
749 /* helper function to cast into the data area of the leaf. */
750 #define btrfs_item_ptr(leaf, slot, type) \
751 	((type *)(btrfs_leaf_data(leaf) + \
752 	btrfs_item_offset((leaf)->items + (slot))))
753 
754 struct btrfs_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
755 					    struct btrfs_root *root);
756 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
757 		  struct btrfs_buffer *buf);
758 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
759 		      *root, u64 blocknr, u64 num_blocks, int pin);
760 int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
761 		      *root, struct btrfs_key *key, struct btrfs_path *p, int
762 		      ins_len, int cow);
763 void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
764 void btrfs_init_path(struct btrfs_path *p);
765 int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
766 		   struct btrfs_path *path);
767 int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
768 		      *root, struct btrfs_key *key, void *data, u32 data_size);
769 int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root
770 			    *root, struct btrfs_path *path, struct btrfs_key
771 			    *cpu_key, u32 data_size);
772 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
773 int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf);
774 int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
775 			*root, struct btrfs_buffer *snap);
776 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct
777 			       btrfs_root *root);
778 int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
779 		   struct btrfs_key *key);
780 int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root
781 		      *root, struct btrfs_key *key, struct btrfs_root_item
782 		      *item);
783 int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
784 		      *root, struct btrfs_key *key, struct btrfs_root_item
785 		      *item);
786 int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct
787 			 btrfs_root_item *item, struct btrfs_key *key);
788 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
789 			  *root, char *name, int name_len, u64 dir, u64
790 			  objectid, u8 type);
791 int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
792 			  *root, struct btrfs_path *path, u64 dir, char *name,
793 			  int name_len, int mod);
794 int btrfs_match_dir_item_name(struct btrfs_root *root, struct btrfs_path *path,
795 			      char *name, int name_len);
796 int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
797 			     struct btrfs_root *fs_root,
798 			     u64 dirid, u64 *objectid);
799 int btrfs_insert_inode_map(struct btrfs_trans_handle *trans,
800 			   struct btrfs_root *root,
801 			   u64 objectid, struct btrfs_key *location);
802 int btrfs_lookup_inode_map(struct btrfs_trans_handle *trans,
803 			   struct btrfs_root *root, struct btrfs_path *path,
804 			   u64 objectid, int mod);
805 #endif
806