xref: /linux/fs/xfs/libxfs/xfs_btree.h (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 #ifndef __XFS_BTREE_H__
7 #define	__XFS_BTREE_H__
8 
9 struct xfs_buf;
10 struct xfs_inode;
11 struct xfs_mount;
12 struct xfs_trans;
13 struct xfs_ifork;
14 struct xfs_perag;
15 
16 /*
17  * Generic key, ptr and record wrapper structures.
18  *
19  * These are disk format structures, and are converted where necessary
20  * by the btree specific code that needs to interpret them.
21  */
22 union xfs_btree_ptr {
23 	__be32			s;	/* short form ptr */
24 	__be64			l;	/* long form ptr */
25 };
26 
27 /*
28  * The in-core btree key.  Overlapping btrees actually store two keys
29  * per pointer, so we reserve enough memory to hold both.  The __*bigkey
30  * items should never be accessed directly.
31  */
32 union xfs_btree_key {
33 	struct xfs_bmbt_key		bmbt;
34 	xfs_bmdr_key_t			bmbr;	/* bmbt root block */
35 	xfs_alloc_key_t			alloc;
36 	struct xfs_inobt_key		inobt;
37 	struct xfs_rmap_key		rmap;
38 	struct xfs_rmap_key		__rmap_bigkey[2];
39 	struct xfs_refcount_key		refc;
40 };
41 
42 union xfs_btree_rec {
43 	struct xfs_bmbt_rec		bmbt;
44 	xfs_bmdr_rec_t			bmbr;	/* bmbt root block */
45 	struct xfs_alloc_rec		alloc;
46 	struct xfs_inobt_rec		inobt;
47 	struct xfs_rmap_rec		rmap;
48 	struct xfs_refcount_rec		refc;
49 };
50 
51 /*
52  * This nonsense is to make -wlint happy.
53  */
54 #define	XFS_LOOKUP_EQ	((xfs_lookup_t)XFS_LOOKUP_EQi)
55 #define	XFS_LOOKUP_LE	((xfs_lookup_t)XFS_LOOKUP_LEi)
56 #define	XFS_LOOKUP_GE	((xfs_lookup_t)XFS_LOOKUP_GEi)
57 
58 struct xfs_btree_ops;
59 uint32_t xfs_btree_magic(struct xfs_mount *mp, const struct xfs_btree_ops *ops);
60 
61 /*
62  * For logging record fields.
63  */
64 #define	XFS_BB_MAGIC		(1u << 0)
65 #define	XFS_BB_LEVEL		(1u << 1)
66 #define	XFS_BB_NUMRECS		(1u << 2)
67 #define	XFS_BB_LEFTSIB		(1u << 3)
68 #define	XFS_BB_RIGHTSIB		(1u << 4)
69 #define	XFS_BB_BLKNO		(1u << 5)
70 #define	XFS_BB_LSN		(1u << 6)
71 #define	XFS_BB_UUID		(1u << 7)
72 #define	XFS_BB_OWNER		(1u << 8)
73 #define	XFS_BB_NUM_BITS		5
74 #define	XFS_BB_ALL_BITS		((1u << XFS_BB_NUM_BITS) - 1)
75 #define	XFS_BB_NUM_BITS_CRC	9
76 #define	XFS_BB_ALL_BITS_CRC	((1u << XFS_BB_NUM_BITS_CRC) - 1)
77 
78 /*
79  * Generic stats interface
80  */
81 #define XFS_BTREE_STATS_INC(cur, stat)	\
82 	XFS_STATS_INC_OFF((cur)->bc_mp, \
83 		(cur)->bc_ops->statoff + __XBTS_ ## stat)
84 #define XFS_BTREE_STATS_ADD(cur, stat, val)	\
85 	XFS_STATS_ADD_OFF((cur)->bc_mp, \
86 		(cur)->bc_ops->statoff + __XBTS_ ## stat, val)
87 
88 enum xbtree_key_contig {
89 	XBTREE_KEY_GAP = 0,
90 	XBTREE_KEY_CONTIGUOUS,
91 	XBTREE_KEY_OVERLAP,
92 };
93 
94 /*
95  * Decide if these two numeric btree key fields are contiguous, overlapping,
96  * or if there's a gap between them.  @x should be the field from the high
97  * key and @y should be the field from the low key.
98  */
99 static inline enum xbtree_key_contig xbtree_key_contig(uint64_t x, uint64_t y)
100 {
101 	x++;
102 	if (x < y)
103 		return XBTREE_KEY_GAP;
104 	if (x == y)
105 		return XBTREE_KEY_CONTIGUOUS;
106 	return XBTREE_KEY_OVERLAP;
107 }
108 
109 #define XFS_BTREE_LONG_PTR_LEN		(sizeof(__be64))
110 #define XFS_BTREE_SHORT_PTR_LEN		(sizeof(__be32))
111 
112 enum xfs_btree_type {
113 	XFS_BTREE_TYPE_AG,
114 	XFS_BTREE_TYPE_INODE,
115 	XFS_BTREE_TYPE_MEM,
116 };
117 
118 struct xfs_btree_ops {
119 	const char		*name;
120 
121 	/* Type of btree - AG-rooted or inode-rooted */
122 	enum xfs_btree_type	type;
123 
124 	/* XFS_BTGEO_* flags that determine the geometry of the btree */
125 	unsigned int		geom_flags;
126 
127 	/* size of the key, pointer, and record structures */
128 	size_t			key_len;
129 	size_t			ptr_len;
130 	size_t			rec_len;
131 
132 	/* LRU refcount to set on each btree buffer created */
133 	unsigned int		lru_refs;
134 
135 	/* offset of btree stats array */
136 	unsigned int		statoff;
137 
138 	/* sick mask for health reporting (only for XFS_BTREE_TYPE_AG) */
139 	unsigned int		sick_mask;
140 
141 	/* cursor operations */
142 	struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
143 	void	(*update_cursor)(struct xfs_btree_cur *src,
144 				 struct xfs_btree_cur *dst);
145 
146 	/* update btree root pointer */
147 	void	(*set_root)(struct xfs_btree_cur *cur,
148 			    const union xfs_btree_ptr *nptr, int level_change);
149 
150 	/* block allocation / freeing */
151 	int	(*alloc_block)(struct xfs_btree_cur *cur,
152 			       const union xfs_btree_ptr *start_bno,
153 			       union xfs_btree_ptr *new_bno,
154 			       int *stat);
155 	int	(*free_block)(struct xfs_btree_cur *cur, struct xfs_buf *bp);
156 
157 	/* update last record information */
158 	void	(*update_lastrec)(struct xfs_btree_cur *cur,
159 				  const struct xfs_btree_block *block,
160 				  const union xfs_btree_rec *rec,
161 				  int ptr, int reason);
162 
163 	/* records in block/level */
164 	int	(*get_minrecs)(struct xfs_btree_cur *cur, int level);
165 	int	(*get_maxrecs)(struct xfs_btree_cur *cur, int level);
166 
167 	/* records on disk.  Matter for the root in inode case. */
168 	int	(*get_dmaxrecs)(struct xfs_btree_cur *cur, int level);
169 
170 	/* init values of btree structures */
171 	void	(*init_key_from_rec)(union xfs_btree_key *key,
172 				     const union xfs_btree_rec *rec);
173 	void	(*init_rec_from_cur)(struct xfs_btree_cur *cur,
174 				     union xfs_btree_rec *rec);
175 	void	(*init_ptr_from_cur)(struct xfs_btree_cur *cur,
176 				     union xfs_btree_ptr *ptr);
177 	void	(*init_high_key_from_rec)(union xfs_btree_key *key,
178 					  const union xfs_btree_rec *rec);
179 
180 	/* difference between key value and cursor value */
181 	int64_t (*key_diff)(struct xfs_btree_cur *cur,
182 			    const union xfs_btree_key *key);
183 
184 	/*
185 	 * Difference between key2 and key1 -- positive if key1 > key2,
186 	 * negative if key1 < key2, and zero if equal.  If the @mask parameter
187 	 * is non NULL, each key field to be used in the comparison must
188 	 * contain a nonzero value.
189 	 */
190 	int64_t (*diff_two_keys)(struct xfs_btree_cur *cur,
191 				 const union xfs_btree_key *key1,
192 				 const union xfs_btree_key *key2,
193 				 const union xfs_btree_key *mask);
194 
195 	const struct xfs_buf_ops	*buf_ops;
196 
197 	/* check that k1 is lower than k2 */
198 	int	(*keys_inorder)(struct xfs_btree_cur *cur,
199 				const union xfs_btree_key *k1,
200 				const union xfs_btree_key *k2);
201 
202 	/* check that r1 is lower than r2 */
203 	int	(*recs_inorder)(struct xfs_btree_cur *cur,
204 				const union xfs_btree_rec *r1,
205 				const union xfs_btree_rec *r2);
206 
207 	/*
208 	 * Are these two btree keys immediately adjacent?
209 	 *
210 	 * Given two btree keys @key1 and @key2, decide if it is impossible for
211 	 * there to be a third btree key K satisfying the relationship
212 	 * @key1 < K < @key2.  To determine if two btree records are
213 	 * immediately adjacent, @key1 should be the high key of the first
214 	 * record and @key2 should be the low key of the second record.
215 	 * If the @mask parameter is non NULL, each key field to be used in the
216 	 * comparison must contain a nonzero value.
217 	 */
218 	enum xbtree_key_contig (*keys_contiguous)(struct xfs_btree_cur *cur,
219 			       const union xfs_btree_key *key1,
220 			       const union xfs_btree_key *key2,
221 			       const union xfs_btree_key *mask);
222 };
223 
224 /* btree geometry flags */
225 #define XFS_BTGEO_LASTREC_UPDATE	(1U << 0) /* track last rec externally */
226 #define XFS_BTGEO_OVERLAPPING		(1U << 1) /* overlapping intervals */
227 
228 /*
229  * Reasons for the update_lastrec method to be called.
230  */
231 #define LASTREC_UPDATE	0
232 #define LASTREC_INSREC	1
233 #define LASTREC_DELREC	2
234 
235 
236 union xfs_btree_irec {
237 	struct xfs_alloc_rec_incore	a;
238 	struct xfs_bmbt_irec		b;
239 	struct xfs_inobt_rec_incore	i;
240 	struct xfs_rmap_irec		r;
241 	struct xfs_refcount_irec	rc;
242 };
243 
244 struct xfs_btree_level {
245 	/* buffer pointer */
246 	struct xfs_buf		*bp;
247 
248 	/* key/record number */
249 	uint16_t		ptr;
250 
251 	/* readahead info */
252 #define XFS_BTCUR_LEFTRA	(1 << 0) /* left sibling has been read-ahead */
253 #define XFS_BTCUR_RIGHTRA	(1 << 1) /* right sibling has been read-ahead */
254 	uint16_t		ra;
255 };
256 
257 /*
258  * Btree cursor structure.
259  * This collects all information needed by the btree code in one place.
260  */
261 struct xfs_btree_cur
262 {
263 	struct xfs_trans	*bc_tp;	/* transaction we're in, if any */
264 	struct xfs_mount	*bc_mp;	/* file system mount struct */
265 	const struct xfs_btree_ops *bc_ops;
266 	struct kmem_cache	*bc_cache; /* cursor cache */
267 	unsigned int		bc_flags; /* btree features - below */
268 	union xfs_btree_irec	bc_rec;	/* current insert/search record value */
269 	uint8_t			bc_nlevels; /* number of levels in the tree */
270 	uint8_t			bc_maxlevels; /* maximum levels for this btree type */
271 
272 	/* per-type information */
273 	union {
274 		struct {
275 			struct xfs_inode	*ip;
276 			short			forksize;
277 			char			whichfork;
278 			struct xbtree_ifakeroot	*ifake;	/* for staging cursor */
279 		} bc_ino;
280 		struct {
281 			struct xfs_perag	*pag;
282 			struct xfs_buf		*agbp;
283 			struct xbtree_afakeroot	*afake;	/* for staging cursor */
284 		} bc_ag;
285 		struct {
286 			struct xfbtree		*xfbtree;
287 			struct xfs_perag	*pag;
288 		} bc_mem;
289 	};
290 
291 	/* per-format private data */
292 	union {
293 		struct {
294 			int		allocated;
295 		} bc_bmap;	/* bmapbt */
296 		struct {
297 			unsigned int	nr_ops;		/* # record updates */
298 			unsigned int	shape_changes;	/* # of extent splits */
299 		} bc_refc;	/* refcountbt */
300 	};
301 
302 	/* Must be at the end of the struct! */
303 	struct xfs_btree_level	bc_levels[];
304 };
305 
306 /*
307  * Compute the size of a btree cursor that can handle a btree of a given
308  * height.  The bc_levels array handles node and leaf blocks, so its size
309  * is exactly nlevels.
310  */
311 static inline size_t
312 xfs_btree_cur_sizeof(unsigned int nlevels)
313 {
314 	return struct_size_t(struct xfs_btree_cur, bc_levels, nlevels);
315 }
316 
317 /* cursor state flags */
318 /*
319  * The root of this btree is a fakeroot structure so that we can stage a btree
320  * rebuild without leaving it accessible via primary metadata.  The ops struct
321  * is dynamically allocated and must be freed when the cursor is deleted.
322  */
323 #define XFS_BTREE_STAGING		(1U << 0)
324 
325 /* We are converting a delalloc reservation (only for bmbt btrees) */
326 #define	XFS_BTREE_BMBT_WASDEL		(1U << 1)
327 
328 /* For extent swap, ignore owner check in verifier (only for bmbt btrees) */
329 #define	XFS_BTREE_BMBT_INVALID_OWNER	(1U << 2)
330 
331 /* Cursor is active (only for allocbt btrees) */
332 #define	XFS_BTREE_ALLOCBT_ACTIVE	(1U << 3)
333 
334 #define	XFS_BTREE_NOERROR	0
335 #define	XFS_BTREE_ERROR		1
336 
337 /*
338  * Convert from buffer to btree block header.
339  */
340 #define	XFS_BUF_TO_BLOCK(bp)	((struct xfs_btree_block *)((bp)->b_addr))
341 
342 xfs_failaddr_t __xfs_btree_check_block(struct xfs_btree_cur *cur,
343 		struct xfs_btree_block *block, int level, struct xfs_buf *bp);
344 int __xfs_btree_check_ptr(struct xfs_btree_cur *cur,
345 		const union xfs_btree_ptr *ptr, int index, int level);
346 
347 /*
348  * Check that block header is ok.
349  */
350 int
351 xfs_btree_check_block(
352 	struct xfs_btree_cur	*cur,	/* btree cursor */
353 	struct xfs_btree_block	*block,	/* generic btree block pointer */
354 	int			level,	/* level of the btree block */
355 	struct xfs_buf		*bp);	/* buffer containing block, if any */
356 
357 /*
358  * Delete the btree cursor.
359  */
360 void
361 xfs_btree_del_cursor(
362 	struct xfs_btree_cur	*cur,	/* btree cursor */
363 	int			error);	/* del because of error */
364 
365 /*
366  * Duplicate the btree cursor.
367  * Allocate a new one, copy the record, re-get the buffers.
368  */
369 int					/* error */
370 xfs_btree_dup_cursor(
371 	struct xfs_btree_cur		*cur,	/* input cursor */
372 	struct xfs_btree_cur		**ncur);/* output cursor */
373 
374 /*
375  * Compute first and last byte offsets for the fields given.
376  * Interprets the offsets table, which contains struct field offsets.
377  */
378 void
379 xfs_btree_offsets(
380 	uint32_t		fields,	/* bitmask of fields */
381 	const short		*offsets,/* table of field offsets */
382 	int			nbits,	/* number of bits to inspect */
383 	int			*first,	/* output: first byte offset */
384 	int			*last);	/* output: last byte offset */
385 
386 /*
387  * Initialise a new btree block header
388  */
389 void xfs_btree_init_buf(struct xfs_mount *mp, struct xfs_buf *bp,
390 		const struct xfs_btree_ops *ops, __u16 level, __u16 numrecs,
391 		__u64 owner);
392 void xfs_btree_init_block(struct xfs_mount *mp,
393 		struct xfs_btree_block *buf, const struct xfs_btree_ops *ops,
394 		__u16 level, __u16 numrecs, __u64 owner);
395 
396 /*
397  * Common btree core entry points.
398  */
399 int xfs_btree_increment(struct xfs_btree_cur *, int, int *);
400 int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
401 int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
402 int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
403 int xfs_btree_new_iroot(struct xfs_btree_cur *, int *, int *);
404 int xfs_btree_insert(struct xfs_btree_cur *, int *);
405 int xfs_btree_delete(struct xfs_btree_cur *, int *);
406 int xfs_btree_get_rec(struct xfs_btree_cur *, union xfs_btree_rec **, int *);
407 int xfs_btree_change_owner(struct xfs_btree_cur *cur, uint64_t new_owner,
408 			   struct list_head *buffer_list);
409 
410 /*
411  * btree block CRC helpers
412  */
413 void xfs_btree_fsblock_calc_crc(struct xfs_buf *);
414 bool xfs_btree_fsblock_verify_crc(struct xfs_buf *);
415 void xfs_btree_agblock_calc_crc(struct xfs_buf *);
416 bool xfs_btree_agblock_verify_crc(struct xfs_buf *);
417 
418 /*
419  * Internal btree helpers also used by xfs_bmap.c.
420  */
421 void xfs_btree_log_block(struct xfs_btree_cur *, struct xfs_buf *, uint32_t);
422 void xfs_btree_log_recs(struct xfs_btree_cur *, struct xfs_buf *, int, int);
423 
424 /*
425  * Helpers.
426  */
427 static inline int xfs_btree_get_numrecs(const struct xfs_btree_block *block)
428 {
429 	return be16_to_cpu(block->bb_numrecs);
430 }
431 
432 static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block,
433 		uint16_t numrecs)
434 {
435 	block->bb_numrecs = cpu_to_be16(numrecs);
436 }
437 
438 static inline int xfs_btree_get_level(const struct xfs_btree_block *block)
439 {
440 	return be16_to_cpu(block->bb_level);
441 }
442 
443 
444 /*
445  * Min and max functions for extlen, agblock, fileoff, and filblks types.
446  */
447 #define	XFS_EXTLEN_MIN(a,b)	min_t(xfs_extlen_t, (a), (b))
448 #define	XFS_EXTLEN_MAX(a,b)	max_t(xfs_extlen_t, (a), (b))
449 #define	XFS_AGBLOCK_MIN(a,b)	min_t(xfs_agblock_t, (a), (b))
450 #define	XFS_AGBLOCK_MAX(a,b)	max_t(xfs_agblock_t, (a), (b))
451 #define	XFS_FILEOFF_MIN(a,b)	min_t(xfs_fileoff_t, (a), (b))
452 #define	XFS_FILEOFF_MAX(a,b)	max_t(xfs_fileoff_t, (a), (b))
453 #define	XFS_FILBLKS_MIN(a,b)	min_t(xfs_filblks_t, (a), (b))
454 #define	XFS_FILBLKS_MAX(a,b)	max_t(xfs_filblks_t, (a), (b))
455 
456 xfs_failaddr_t xfs_btree_agblock_v5hdr_verify(struct xfs_buf *bp);
457 xfs_failaddr_t xfs_btree_agblock_verify(struct xfs_buf *bp,
458 		unsigned int max_recs);
459 xfs_failaddr_t xfs_btree_fsblock_v5hdr_verify(struct xfs_buf *bp,
460 		uint64_t owner);
461 xfs_failaddr_t xfs_btree_fsblock_verify(struct xfs_buf *bp,
462 		unsigned int max_recs);
463 xfs_failaddr_t xfs_btree_memblock_verify(struct xfs_buf *bp,
464 		unsigned int max_recs);
465 
466 unsigned int xfs_btree_compute_maxlevels(const unsigned int *limits,
467 		unsigned long long records);
468 unsigned long long xfs_btree_calc_size(const unsigned int *limits,
469 		unsigned long long records);
470 unsigned int xfs_btree_space_to_height(const unsigned int *limits,
471 		unsigned long long blocks);
472 
473 /*
474  * Return codes for the query range iterator function are 0 to continue
475  * iterating, and non-zero to stop iterating.  Any non-zero value will be
476  * passed up to the _query_range caller.  The special value -ECANCELED can be
477  * used to stop iteration, because _query_range never generates that error
478  * code on its own.
479  */
480 typedef int (*xfs_btree_query_range_fn)(struct xfs_btree_cur *cur,
481 		const union xfs_btree_rec *rec, void *priv);
482 
483 int xfs_btree_query_range(struct xfs_btree_cur *cur,
484 		const union xfs_btree_irec *low_rec,
485 		const union xfs_btree_irec *high_rec,
486 		xfs_btree_query_range_fn fn, void *priv);
487 int xfs_btree_query_all(struct xfs_btree_cur *cur, xfs_btree_query_range_fn fn,
488 		void *priv);
489 
490 typedef int (*xfs_btree_visit_blocks_fn)(struct xfs_btree_cur *cur, int level,
491 		void *data);
492 /* Visit record blocks. */
493 #define XFS_BTREE_VISIT_RECORDS		(1 << 0)
494 /* Visit leaf blocks. */
495 #define XFS_BTREE_VISIT_LEAVES		(1 << 1)
496 /* Visit all blocks. */
497 #define XFS_BTREE_VISIT_ALL		(XFS_BTREE_VISIT_RECORDS | \
498 					 XFS_BTREE_VISIT_LEAVES)
499 int xfs_btree_visit_blocks(struct xfs_btree_cur *cur,
500 		xfs_btree_visit_blocks_fn fn, unsigned int flags, void *data);
501 
502 int xfs_btree_count_blocks(struct xfs_btree_cur *cur, xfs_extlen_t *blocks);
503 
504 union xfs_btree_rec *xfs_btree_rec_addr(struct xfs_btree_cur *cur, int n,
505 		struct xfs_btree_block *block);
506 union xfs_btree_key *xfs_btree_key_addr(struct xfs_btree_cur *cur, int n,
507 		struct xfs_btree_block *block);
508 union xfs_btree_key *xfs_btree_high_key_addr(struct xfs_btree_cur *cur, int n,
509 		struct xfs_btree_block *block);
510 union xfs_btree_ptr *xfs_btree_ptr_addr(struct xfs_btree_cur *cur, int n,
511 		struct xfs_btree_block *block);
512 int xfs_btree_lookup_get_block(struct xfs_btree_cur *cur, int level,
513 		const union xfs_btree_ptr *pp, struct xfs_btree_block **blkp);
514 struct xfs_btree_block *xfs_btree_get_block(struct xfs_btree_cur *cur,
515 		int level, struct xfs_buf **bpp);
516 bool xfs_btree_ptr_is_null(struct xfs_btree_cur *cur,
517 		const union xfs_btree_ptr *ptr);
518 int64_t xfs_btree_diff_two_ptrs(struct xfs_btree_cur *cur,
519 				const union xfs_btree_ptr *a,
520 				const union xfs_btree_ptr *b);
521 void xfs_btree_get_sibling(struct xfs_btree_cur *cur,
522 			   struct xfs_btree_block *block,
523 			   union xfs_btree_ptr *ptr, int lr);
524 void xfs_btree_get_keys(struct xfs_btree_cur *cur,
525 		struct xfs_btree_block *block, union xfs_btree_key *key);
526 union xfs_btree_key *xfs_btree_high_key_from_key(struct xfs_btree_cur *cur,
527 		union xfs_btree_key *key);
528 typedef bool (*xfs_btree_key_gap_fn)(struct xfs_btree_cur *cur,
529 		const union xfs_btree_key *key1,
530 		const union xfs_btree_key *key2);
531 
532 int xfs_btree_has_records(struct xfs_btree_cur *cur,
533 		const union xfs_btree_irec *low,
534 		const union xfs_btree_irec *high,
535 		const union xfs_btree_key *mask,
536 		enum xbtree_recpacking *outcome);
537 
538 bool xfs_btree_has_more_records(struct xfs_btree_cur *cur);
539 struct xfs_ifork *xfs_btree_ifork_ptr(struct xfs_btree_cur *cur);
540 
541 /* Key comparison helpers */
542 static inline bool
543 xfs_btree_keycmp_lt(
544 	struct xfs_btree_cur		*cur,
545 	const union xfs_btree_key	*key1,
546 	const union xfs_btree_key	*key2)
547 {
548 	return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) < 0;
549 }
550 
551 static inline bool
552 xfs_btree_keycmp_gt(
553 	struct xfs_btree_cur		*cur,
554 	const union xfs_btree_key	*key1,
555 	const union xfs_btree_key	*key2)
556 {
557 	return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) > 0;
558 }
559 
560 static inline bool
561 xfs_btree_keycmp_eq(
562 	struct xfs_btree_cur		*cur,
563 	const union xfs_btree_key	*key1,
564 	const union xfs_btree_key	*key2)
565 {
566 	return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) == 0;
567 }
568 
569 static inline bool
570 xfs_btree_keycmp_le(
571 	struct xfs_btree_cur		*cur,
572 	const union xfs_btree_key	*key1,
573 	const union xfs_btree_key	*key2)
574 {
575 	return !xfs_btree_keycmp_gt(cur, key1, key2);
576 }
577 
578 static inline bool
579 xfs_btree_keycmp_ge(
580 	struct xfs_btree_cur		*cur,
581 	const union xfs_btree_key	*key1,
582 	const union xfs_btree_key	*key2)
583 {
584 	return !xfs_btree_keycmp_lt(cur, key1, key2);
585 }
586 
587 static inline bool
588 xfs_btree_keycmp_ne(
589 	struct xfs_btree_cur		*cur,
590 	const union xfs_btree_key	*key1,
591 	const union xfs_btree_key	*key2)
592 {
593 	return !xfs_btree_keycmp_eq(cur, key1, key2);
594 }
595 
596 /* Masked key comparison helpers */
597 static inline bool
598 xfs_btree_masked_keycmp_lt(
599 	struct xfs_btree_cur		*cur,
600 	const union xfs_btree_key	*key1,
601 	const union xfs_btree_key	*key2,
602 	const union xfs_btree_key	*mask)
603 {
604 	return cur->bc_ops->diff_two_keys(cur, key1, key2, mask) < 0;
605 }
606 
607 static inline bool
608 xfs_btree_masked_keycmp_gt(
609 	struct xfs_btree_cur		*cur,
610 	const union xfs_btree_key	*key1,
611 	const union xfs_btree_key	*key2,
612 	const union xfs_btree_key	*mask)
613 {
614 	return cur->bc_ops->diff_two_keys(cur, key1, key2, mask) > 0;
615 }
616 
617 static inline bool
618 xfs_btree_masked_keycmp_ge(
619 	struct xfs_btree_cur		*cur,
620 	const union xfs_btree_key	*key1,
621 	const union xfs_btree_key	*key2,
622 	const union xfs_btree_key	*mask)
623 {
624 	return !xfs_btree_masked_keycmp_lt(cur, key1, key2, mask);
625 }
626 
627 /* Does this cursor point to the last block in the given level? */
628 static inline bool
629 xfs_btree_islastblock(
630 	struct xfs_btree_cur	*cur,
631 	int			level)
632 {
633 	struct xfs_btree_block	*block;
634 	struct xfs_buf		*bp;
635 
636 	block = xfs_btree_get_block(cur, level, &bp);
637 
638 	if (cur->bc_ops->ptr_len == XFS_BTREE_LONG_PTR_LEN)
639 		return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK);
640 	return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
641 }
642 
643 void xfs_btree_set_ptr_null(struct xfs_btree_cur *cur,
644 		union xfs_btree_ptr *ptr);
645 int xfs_btree_get_buf_block(struct xfs_btree_cur *cur,
646 		const union xfs_btree_ptr *ptr, struct xfs_btree_block **block,
647 		struct xfs_buf **bpp);
648 int xfs_btree_read_buf_block(struct xfs_btree_cur *cur,
649 		const union xfs_btree_ptr *ptr, int flags,
650 		struct xfs_btree_block **block, struct xfs_buf **bpp);
651 void xfs_btree_set_sibling(struct xfs_btree_cur *cur,
652 		struct xfs_btree_block *block, const union xfs_btree_ptr *ptr,
653 		int lr);
654 void xfs_btree_init_block_cur(struct xfs_btree_cur *cur,
655 		struct xfs_buf *bp, int level, int numrecs);
656 void xfs_btree_copy_ptrs(struct xfs_btree_cur *cur,
657 		union xfs_btree_ptr *dst_ptr,
658 		const union xfs_btree_ptr *src_ptr, int numptrs);
659 void xfs_btree_copy_keys(struct xfs_btree_cur *cur,
660 		union xfs_btree_key *dst_key,
661 		const union xfs_btree_key *src_key, int numkeys);
662 void xfs_btree_init_ptr_from_cur(struct xfs_btree_cur *cur,
663 		union xfs_btree_ptr *ptr);
664 
665 static inline struct xfs_btree_cur *
666 xfs_btree_alloc_cursor(
667 	struct xfs_mount	*mp,
668 	struct xfs_trans	*tp,
669 	const struct xfs_btree_ops *ops,
670 	uint8_t			maxlevels,
671 	struct kmem_cache	*cache)
672 {
673 	struct xfs_btree_cur	*cur;
674 
675 	ASSERT(ops->ptr_len == XFS_BTREE_LONG_PTR_LEN ||
676 	       ops->ptr_len == XFS_BTREE_SHORT_PTR_LEN);
677 
678 	/* BMBT allocations can come through from non-transactional context. */
679 	cur = kmem_cache_zalloc(cache,
680 			GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
681 	cur->bc_ops = ops;
682 	cur->bc_tp = tp;
683 	cur->bc_mp = mp;
684 	cur->bc_maxlevels = maxlevels;
685 	cur->bc_cache = cache;
686 
687 	return cur;
688 }
689 
690 int __init xfs_btree_init_cur_caches(void);
691 void xfs_btree_destroy_cur_caches(void);
692 
693 int xfs_btree_goto_left_edge(struct xfs_btree_cur *cur);
694 
695 /* Does this level of the cursor point to the inode root (and not a block)? */
696 static inline bool
697 xfs_btree_at_iroot(
698 	const struct xfs_btree_cur	*cur,
699 	int				level)
700 {
701 	return cur->bc_ops->type == XFS_BTREE_TYPE_INODE &&
702 	       level == cur->bc_nlevels - 1;
703 }
704 
705 #endif	/* __XFS_BTREE_H__ */
706