xref: /linux/fs/xfs/libxfs/xfs_btree.h (revision b477ff98d903618a1ab8247861f2ea6e70c0f0f8)
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  */
xbtree_key_contig(uint64_t x,uint64_t y)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 (not for bmap btrees) */
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 	/* records in block/level */
158 	int	(*get_minrecs)(struct xfs_btree_cur *cur, int level);
159 	int	(*get_maxrecs)(struct xfs_btree_cur *cur, int level);
160 
161 	/* records on disk.  Matter for the root in inode case. */
162 	int	(*get_dmaxrecs)(struct xfs_btree_cur *cur, int level);
163 
164 	/* init values of btree structures */
165 	void	(*init_key_from_rec)(union xfs_btree_key *key,
166 				     const union xfs_btree_rec *rec);
167 	void	(*init_rec_from_cur)(struct xfs_btree_cur *cur,
168 				     union xfs_btree_rec *rec);
169 	void	(*init_ptr_from_cur)(struct xfs_btree_cur *cur,
170 				     union xfs_btree_ptr *ptr);
171 	void	(*init_high_key_from_rec)(union xfs_btree_key *key,
172 					  const union xfs_btree_rec *rec);
173 
174 	/* difference between key value and cursor value */
175 	int64_t (*key_diff)(struct xfs_btree_cur *cur,
176 			    const union xfs_btree_key *key);
177 
178 	/*
179 	 * Difference between key2 and key1 -- positive if key1 > key2,
180 	 * negative if key1 < key2, and zero if equal.  If the @mask parameter
181 	 * is non NULL, each key field to be used in the comparison must
182 	 * contain a nonzero value.
183 	 */
184 	int64_t (*diff_two_keys)(struct xfs_btree_cur *cur,
185 				 const union xfs_btree_key *key1,
186 				 const union xfs_btree_key *key2,
187 				 const union xfs_btree_key *mask);
188 
189 	const struct xfs_buf_ops	*buf_ops;
190 
191 	/* check that k1 is lower than k2 */
192 	int	(*keys_inorder)(struct xfs_btree_cur *cur,
193 				const union xfs_btree_key *k1,
194 				const union xfs_btree_key *k2);
195 
196 	/* check that r1 is lower than r2 */
197 	int	(*recs_inorder)(struct xfs_btree_cur *cur,
198 				const union xfs_btree_rec *r1,
199 				const union xfs_btree_rec *r2);
200 
201 	/*
202 	 * Are these two btree keys immediately adjacent?
203 	 *
204 	 * Given two btree keys @key1 and @key2, decide if it is impossible for
205 	 * there to be a third btree key K satisfying the relationship
206 	 * @key1 < K < @key2.  To determine if two btree records are
207 	 * immediately adjacent, @key1 should be the high key of the first
208 	 * record and @key2 should be the low key of the second record.
209 	 * If the @mask parameter is non NULL, each key field to be used in the
210 	 * comparison must contain a nonzero value.
211 	 */
212 	enum xbtree_key_contig (*keys_contiguous)(struct xfs_btree_cur *cur,
213 			       const union xfs_btree_key *key1,
214 			       const union xfs_btree_key *key2,
215 			       const union xfs_btree_key *mask);
216 
217 	/*
218 	 * Reallocate the space for if_broot to fit the number of records.
219 	 * Move the records and pointers in if_broot to fit the new size.  When
220 	 * shrinking this will eliminate holes between the records and pointers
221 	 * created by the caller.  When growing this will create holes to be
222 	 * filled in by the caller.
223 	 *
224 	 * The caller must not request to add more records than would fit in
225 	 * the on-disk inode root.  If the if_broot is currently NULL, then if
226 	 * we are adding records, one will be allocated.  The caller must also
227 	 * not request that the number of records go below zero, although it
228 	 * can go to zero.
229 	 */
230 	struct xfs_btree_block *(*broot_realloc)(struct xfs_btree_cur *cur,
231 				unsigned int new_numrecs);
232 };
233 
234 /* btree geometry flags */
235 #define XFS_BTGEO_OVERLAPPING		(1U << 0) /* overlapping intervals */
236 #define XFS_BTGEO_IROOT_RECORDS		(1U << 1) /* iroot can store records */
237 
238 union xfs_btree_irec {
239 	struct xfs_alloc_rec_incore	a;
240 	struct xfs_bmbt_irec		b;
241 	struct xfs_inobt_rec_incore	i;
242 	struct xfs_rmap_irec		r;
243 	struct xfs_refcount_irec	rc;
244 };
245 
246 struct xfs_btree_level {
247 	/* buffer pointer */
248 	struct xfs_buf		*bp;
249 
250 	/* key/record number */
251 	uint16_t		ptr;
252 
253 	/* readahead info */
254 #define XFS_BTCUR_LEFTRA	(1 << 0) /* left sibling has been read-ahead */
255 #define XFS_BTCUR_RIGHTRA	(1 << 1) /* right sibling has been read-ahead */
256 	uint16_t		ra;
257 };
258 
259 /*
260  * Btree cursor structure.
261  * This collects all information needed by the btree code in one place.
262  */
263 struct xfs_btree_cur
264 {
265 	struct xfs_trans	*bc_tp;	/* transaction we're in, if any */
266 	struct xfs_mount	*bc_mp;	/* file system mount struct */
267 	const struct xfs_btree_ops *bc_ops;
268 	struct kmem_cache	*bc_cache; /* cursor cache */
269 	unsigned int		bc_flags; /* btree features - below */
270 	union xfs_btree_irec	bc_rec;	/* current insert/search record value */
271 	uint8_t			bc_nlevels; /* number of levels in the tree */
272 	uint8_t			bc_maxlevels; /* maximum levels for this btree type */
273 	struct xfs_group	*bc_group;
274 
275 	/* per-type information */
276 	union {
277 		struct {
278 			struct xfs_inode	*ip;
279 			short			forksize;
280 			char			whichfork;
281 			struct xbtree_ifakeroot	*ifake;	/* for staging cursor */
282 		} bc_ino;
283 		struct {
284 			struct xfs_buf		*agbp;
285 			struct xbtree_afakeroot	*afake;	/* for staging cursor */
286 		} bc_ag;
287 		struct {
288 			struct xfbtree		*xfbtree;
289 		} bc_mem;
290 	};
291 
292 	/* per-format private data */
293 	union {
294 		struct {
295 			int		allocated;
296 		} bc_bmap;	/* bmapbt */
297 		struct {
298 			unsigned int	nr_ops;		/* # record updates */
299 			unsigned int	shape_changes;	/* # of extent splits */
300 		} bc_refc;	/* refcountbt/rtrefcountbt */
301 	};
302 
303 	/* Must be at the end of the struct! */
304 	struct xfs_btree_level	bc_levels[];
305 };
306 
307 /*
308  * Compute the size of a btree cursor that can handle a btree of a given
309  * height.  The bc_levels array handles node and leaf blocks, so its size
310  * is exactly nlevels.
311  */
312 static inline size_t
xfs_btree_cur_sizeof(unsigned int nlevels)313 xfs_btree_cur_sizeof(unsigned int nlevels)
314 {
315 	return struct_size_t(struct xfs_btree_cur, bc_levels, nlevels);
316 }
317 
318 /* cursor state flags */
319 /*
320  * The root of this btree is a fakeroot structure so that we can stage a btree
321  * rebuild without leaving it accessible via primary metadata.  The ops struct
322  * is dynamically allocated and must be freed when the cursor is deleted.
323  */
324 #define XFS_BTREE_STAGING		(1U << 0)
325 
326 /* We are converting a delalloc reservation (only for bmbt btrees) */
327 #define	XFS_BTREE_BMBT_WASDEL		(1U << 1)
328 
329 /* For extent swap, ignore owner check in verifier (only for bmbt btrees) */
330 #define	XFS_BTREE_BMBT_INVALID_OWNER	(1U << 2)
331 
332 /* Cursor is active (only for allocbt btrees) */
333 #define	XFS_BTREE_ALLOCBT_ACTIVE	(1U << 3)
334 
335 #define	XFS_BTREE_NOERROR	0
336 #define	XFS_BTREE_ERROR		1
337 
338 /*
339  * Convert from buffer to btree block header.
340  */
341 #define	XFS_BUF_TO_BLOCK(bp)	((struct xfs_btree_block *)((bp)->b_addr))
342 
343 xfs_failaddr_t __xfs_btree_check_block(struct xfs_btree_cur *cur,
344 		struct xfs_btree_block *block, int level, struct xfs_buf *bp);
345 int __xfs_btree_check_ptr(struct xfs_btree_cur *cur,
346 		const union xfs_btree_ptr *ptr, int index, int level);
347 
348 /*
349  * Check that block header is ok.
350  */
351 int
352 xfs_btree_check_block(
353 	struct xfs_btree_cur	*cur,	/* btree cursor */
354 	struct xfs_btree_block	*block,	/* generic btree block pointer */
355 	int			level,	/* level of the btree block */
356 	struct xfs_buf		*bp);	/* buffer containing block, if any */
357 
358 /*
359  * Delete the btree cursor.
360  */
361 void
362 xfs_btree_del_cursor(
363 	struct xfs_btree_cur	*cur,	/* btree cursor */
364 	int			error);	/* del because of error */
365 
366 /*
367  * Duplicate the btree cursor.
368  * Allocate a new one, copy the record, re-get the buffers.
369  */
370 int					/* error */
371 xfs_btree_dup_cursor(
372 	struct xfs_btree_cur		*cur,	/* input cursor */
373 	struct xfs_btree_cur		**ncur);/* output cursor */
374 
375 /*
376  * Compute first and last byte offsets for the fields given.
377  * Interprets the offsets table, which contains struct field offsets.
378  */
379 void
380 xfs_btree_offsets(
381 	uint32_t		fields,	/* bitmask of fields */
382 	const short		*offsets,/* table of field offsets */
383 	int			nbits,	/* number of bits to inspect */
384 	int			*first,	/* output: first byte offset */
385 	int			*last);	/* output: last byte offset */
386 
387 /*
388  * Initialise a new btree block header
389  */
390 void xfs_btree_init_buf(struct xfs_mount *mp, struct xfs_buf *bp,
391 		const struct xfs_btree_ops *ops, __u16 level, __u16 numrecs,
392 		__u64 owner);
393 void xfs_btree_init_block(struct xfs_mount *mp,
394 		struct xfs_btree_block *buf, const struct xfs_btree_ops *ops,
395 		__u16 level, __u16 numrecs, __u64 owner);
396 
397 /*
398  * Common btree core entry points.
399  */
400 int xfs_btree_increment(struct xfs_btree_cur *, int, int *);
401 int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
402 int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
403 int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
404 int xfs_btree_new_iroot(struct xfs_btree_cur *, int *, int *);
405 int xfs_btree_insert(struct xfs_btree_cur *, int *);
406 int xfs_btree_delete(struct xfs_btree_cur *, int *);
407 int xfs_btree_get_rec(struct xfs_btree_cur *, union xfs_btree_rec **, int *);
408 int xfs_btree_change_owner(struct xfs_btree_cur *cur, uint64_t new_owner,
409 			   struct list_head *buffer_list);
410 
411 /*
412  * btree block CRC helpers
413  */
414 void xfs_btree_fsblock_calc_crc(struct xfs_buf *);
415 bool xfs_btree_fsblock_verify_crc(struct xfs_buf *);
416 void xfs_btree_agblock_calc_crc(struct xfs_buf *);
417 bool xfs_btree_agblock_verify_crc(struct xfs_buf *);
418 
419 /*
420  * Internal btree helpers also used by xfs_bmap.c.
421  */
422 void xfs_btree_log_block(struct xfs_btree_cur *, struct xfs_buf *, uint32_t);
423 void xfs_btree_log_recs(struct xfs_btree_cur *, struct xfs_buf *, int, int);
424 
425 /*
426  * Helpers.
427  */
xfs_btree_get_numrecs(const struct xfs_btree_block * block)428 static inline int xfs_btree_get_numrecs(const struct xfs_btree_block *block)
429 {
430 	return be16_to_cpu(block->bb_numrecs);
431 }
432 
xfs_btree_set_numrecs(struct xfs_btree_block * block,uint16_t numrecs)433 static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block,
434 		uint16_t numrecs)
435 {
436 	block->bb_numrecs = cpu_to_be16(numrecs);
437 }
438 
xfs_btree_get_level(const struct xfs_btree_block * block)439 static inline int xfs_btree_get_level(const struct xfs_btree_block *block)
440 {
441 	return be16_to_cpu(block->bb_level);
442 }
443 
444 
445 /*
446  * Min and max functions for extlen, agblock, fileoff, and filblks types.
447  */
448 #define	XFS_EXTLEN_MIN(a,b)	min_t(xfs_extlen_t, (a), (b))
449 #define	XFS_EXTLEN_MAX(a,b)	max_t(xfs_extlen_t, (a), (b))
450 #define	XFS_AGBLOCK_MIN(a,b)	min_t(xfs_agblock_t, (a), (b))
451 #define	XFS_AGBLOCK_MAX(a,b)	max_t(xfs_agblock_t, (a), (b))
452 #define	XFS_FILEOFF_MIN(a,b)	min_t(xfs_fileoff_t, (a), (b))
453 #define	XFS_FILEOFF_MAX(a,b)	max_t(xfs_fileoff_t, (a), (b))
454 #define	XFS_FILBLKS_MIN(a,b)	min_t(xfs_filblks_t, (a), (b))
455 #define	XFS_FILBLKS_MAX(a,b)	max_t(xfs_filblks_t, (a), (b))
456 
457 xfs_failaddr_t xfs_btree_agblock_v5hdr_verify(struct xfs_buf *bp);
458 xfs_failaddr_t xfs_btree_agblock_verify(struct xfs_buf *bp,
459 		unsigned int max_recs);
460 xfs_failaddr_t xfs_btree_fsblock_v5hdr_verify(struct xfs_buf *bp,
461 		uint64_t owner);
462 xfs_failaddr_t xfs_btree_fsblock_verify(struct xfs_buf *bp,
463 		unsigned int max_recs);
464 xfs_failaddr_t xfs_btree_memblock_verify(struct xfs_buf *bp,
465 		unsigned int max_recs);
466 
467 unsigned int xfs_btree_compute_maxlevels(const unsigned int *limits,
468 		unsigned long long records);
469 unsigned long long xfs_btree_calc_size(const unsigned int *limits,
470 		unsigned long long records);
471 unsigned int xfs_btree_space_to_height(const unsigned int *limits,
472 		unsigned long long blocks);
473 
474 /*
475  * Return codes for the query range iterator function are 0 to continue
476  * iterating, and non-zero to stop iterating.  Any non-zero value will be
477  * passed up to the _query_range caller.  The special value -ECANCELED can be
478  * used to stop iteration, because _query_range never generates that error
479  * code on its own.
480  */
481 typedef int (*xfs_btree_query_range_fn)(struct xfs_btree_cur *cur,
482 		const union xfs_btree_rec *rec, void *priv);
483 
484 int xfs_btree_query_range(struct xfs_btree_cur *cur,
485 		const union xfs_btree_irec *low_rec,
486 		const union xfs_btree_irec *high_rec,
487 		xfs_btree_query_range_fn fn, void *priv);
488 int xfs_btree_query_all(struct xfs_btree_cur *cur, xfs_btree_query_range_fn fn,
489 		void *priv);
490 
491 typedef int (*xfs_btree_visit_blocks_fn)(struct xfs_btree_cur *cur, int level,
492 		void *data);
493 /* Visit record blocks. */
494 #define XFS_BTREE_VISIT_RECORDS		(1 << 0)
495 /* Visit leaf blocks. */
496 #define XFS_BTREE_VISIT_LEAVES		(1 << 1)
497 /* Visit all blocks. */
498 #define XFS_BTREE_VISIT_ALL		(XFS_BTREE_VISIT_RECORDS | \
499 					 XFS_BTREE_VISIT_LEAVES)
500 int xfs_btree_visit_blocks(struct xfs_btree_cur *cur,
501 		xfs_btree_visit_blocks_fn fn, unsigned int flags, void *data);
502 
503 int xfs_btree_count_blocks(struct xfs_btree_cur *cur, xfs_filblks_t *blocks);
504 
505 union xfs_btree_rec *xfs_btree_rec_addr(struct xfs_btree_cur *cur, int n,
506 		struct xfs_btree_block *block);
507 union xfs_btree_key *xfs_btree_key_addr(struct xfs_btree_cur *cur, int n,
508 		struct xfs_btree_block *block);
509 union xfs_btree_key *xfs_btree_high_key_addr(struct xfs_btree_cur *cur, int n,
510 		struct xfs_btree_block *block);
511 union xfs_btree_ptr *xfs_btree_ptr_addr(struct xfs_btree_cur *cur, int n,
512 		struct xfs_btree_block *block);
513 int xfs_btree_lookup_get_block(struct xfs_btree_cur *cur, int level,
514 		const union xfs_btree_ptr *pp, struct xfs_btree_block **blkp);
515 struct xfs_btree_block *xfs_btree_get_block(struct xfs_btree_cur *cur,
516 		int level, struct xfs_buf **bpp);
517 bool xfs_btree_ptr_is_null(struct xfs_btree_cur *cur,
518 		const union xfs_btree_ptr *ptr);
519 int64_t xfs_btree_diff_two_ptrs(struct xfs_btree_cur *cur,
520 				const union xfs_btree_ptr *a,
521 				const union xfs_btree_ptr *b);
522 void xfs_btree_get_sibling(struct xfs_btree_cur *cur,
523 			   struct xfs_btree_block *block,
524 			   union xfs_btree_ptr *ptr, int lr);
525 void xfs_btree_get_keys(struct xfs_btree_cur *cur,
526 		struct xfs_btree_block *block, union xfs_btree_key *key);
527 union xfs_btree_key *xfs_btree_high_key_from_key(struct xfs_btree_cur *cur,
528 		union xfs_btree_key *key);
529 typedef bool (*xfs_btree_key_gap_fn)(struct xfs_btree_cur *cur,
530 		const union xfs_btree_key *key1,
531 		const union xfs_btree_key *key2);
532 
533 int xfs_btree_has_records(struct xfs_btree_cur *cur,
534 		const union xfs_btree_irec *low,
535 		const union xfs_btree_irec *high,
536 		const union xfs_btree_key *mask,
537 		enum xbtree_recpacking *outcome);
538 
539 bool xfs_btree_has_more_records(struct xfs_btree_cur *cur);
540 struct xfs_ifork *xfs_btree_ifork_ptr(struct xfs_btree_cur *cur);
541 
542 /* Key comparison helpers */
543 static inline bool
xfs_btree_keycmp_lt(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2)544 xfs_btree_keycmp_lt(
545 	struct xfs_btree_cur		*cur,
546 	const union xfs_btree_key	*key1,
547 	const union xfs_btree_key	*key2)
548 {
549 	return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) < 0;
550 }
551 
552 static inline bool
xfs_btree_keycmp_gt(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2)553 xfs_btree_keycmp_gt(
554 	struct xfs_btree_cur		*cur,
555 	const union xfs_btree_key	*key1,
556 	const union xfs_btree_key	*key2)
557 {
558 	return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) > 0;
559 }
560 
561 static inline bool
xfs_btree_keycmp_eq(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2)562 xfs_btree_keycmp_eq(
563 	struct xfs_btree_cur		*cur,
564 	const union xfs_btree_key	*key1,
565 	const union xfs_btree_key	*key2)
566 {
567 	return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) == 0;
568 }
569 
570 static inline bool
xfs_btree_keycmp_le(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2)571 xfs_btree_keycmp_le(
572 	struct xfs_btree_cur		*cur,
573 	const union xfs_btree_key	*key1,
574 	const union xfs_btree_key	*key2)
575 {
576 	return !xfs_btree_keycmp_gt(cur, key1, key2);
577 }
578 
579 static inline bool
xfs_btree_keycmp_ge(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2)580 xfs_btree_keycmp_ge(
581 	struct xfs_btree_cur		*cur,
582 	const union xfs_btree_key	*key1,
583 	const union xfs_btree_key	*key2)
584 {
585 	return !xfs_btree_keycmp_lt(cur, key1, key2);
586 }
587 
588 static inline bool
xfs_btree_keycmp_ne(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2)589 xfs_btree_keycmp_ne(
590 	struct xfs_btree_cur		*cur,
591 	const union xfs_btree_key	*key1,
592 	const union xfs_btree_key	*key2)
593 {
594 	return !xfs_btree_keycmp_eq(cur, key1, key2);
595 }
596 
597 /* Masked key comparison helpers */
598 static inline bool
xfs_btree_masked_keycmp_lt(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2,const union xfs_btree_key * mask)599 xfs_btree_masked_keycmp_lt(
600 	struct xfs_btree_cur		*cur,
601 	const union xfs_btree_key	*key1,
602 	const union xfs_btree_key	*key2,
603 	const union xfs_btree_key	*mask)
604 {
605 	return cur->bc_ops->diff_two_keys(cur, key1, key2, mask) < 0;
606 }
607 
608 static inline bool
xfs_btree_masked_keycmp_gt(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2,const union xfs_btree_key * mask)609 xfs_btree_masked_keycmp_gt(
610 	struct xfs_btree_cur		*cur,
611 	const union xfs_btree_key	*key1,
612 	const union xfs_btree_key	*key2,
613 	const union xfs_btree_key	*mask)
614 {
615 	return cur->bc_ops->diff_two_keys(cur, key1, key2, mask) > 0;
616 }
617 
618 static inline bool
xfs_btree_masked_keycmp_ge(struct xfs_btree_cur * cur,const union xfs_btree_key * key1,const union xfs_btree_key * key2,const union xfs_btree_key * mask)619 xfs_btree_masked_keycmp_ge(
620 	struct xfs_btree_cur		*cur,
621 	const union xfs_btree_key	*key1,
622 	const union xfs_btree_key	*key2,
623 	const union xfs_btree_key	*mask)
624 {
625 	return !xfs_btree_masked_keycmp_lt(cur, key1, key2, mask);
626 }
627 
628 /* Does this cursor point to the last block in the given level? */
629 static inline bool
xfs_btree_islastblock(struct xfs_btree_cur * cur,int level)630 xfs_btree_islastblock(
631 	struct xfs_btree_cur	*cur,
632 	int			level)
633 {
634 	struct xfs_btree_block	*block;
635 	struct xfs_buf		*bp;
636 
637 	block = xfs_btree_get_block(cur, level, &bp);
638 
639 	if (cur->bc_ops->ptr_len == XFS_BTREE_LONG_PTR_LEN)
640 		return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK);
641 	return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
642 }
643 
644 void xfs_btree_set_ptr_null(struct xfs_btree_cur *cur,
645 		union xfs_btree_ptr *ptr);
646 int xfs_btree_get_buf_block(struct xfs_btree_cur *cur,
647 		const union xfs_btree_ptr *ptr, struct xfs_btree_block **block,
648 		struct xfs_buf **bpp);
649 int xfs_btree_read_buf_block(struct xfs_btree_cur *cur,
650 		const union xfs_btree_ptr *ptr, int flags,
651 		struct xfs_btree_block **block, struct xfs_buf **bpp);
652 void xfs_btree_set_sibling(struct xfs_btree_cur *cur,
653 		struct xfs_btree_block *block, const union xfs_btree_ptr *ptr,
654 		int lr);
655 void xfs_btree_init_block_cur(struct xfs_btree_cur *cur,
656 		struct xfs_buf *bp, int level, int numrecs);
657 void xfs_btree_copy_ptrs(struct xfs_btree_cur *cur,
658 		union xfs_btree_ptr *dst_ptr,
659 		const union xfs_btree_ptr *src_ptr, int numptrs);
660 void xfs_btree_copy_keys(struct xfs_btree_cur *cur,
661 		union xfs_btree_key *dst_key,
662 		const union xfs_btree_key *src_key, int numkeys);
663 void xfs_btree_init_ptr_from_cur(struct xfs_btree_cur *cur,
664 		union xfs_btree_ptr *ptr);
665 
666 static inline struct xfs_btree_cur *
xfs_btree_alloc_cursor(struct xfs_mount * mp,struct xfs_trans * tp,const struct xfs_btree_ops * ops,uint8_t maxlevels,struct kmem_cache * cache)667 xfs_btree_alloc_cursor(
668 	struct xfs_mount	*mp,
669 	struct xfs_trans	*tp,
670 	const struct xfs_btree_ops *ops,
671 	uint8_t			maxlevels,
672 	struct kmem_cache	*cache)
673 {
674 	struct xfs_btree_cur	*cur;
675 
676 	ASSERT(ops->ptr_len == XFS_BTREE_LONG_PTR_LEN ||
677 	       ops->ptr_len == XFS_BTREE_SHORT_PTR_LEN);
678 
679 	/* BMBT allocations can come through from non-transactional context. */
680 	cur = kmem_cache_zalloc(cache,
681 			GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
682 	cur->bc_ops = ops;
683 	cur->bc_tp = tp;
684 	cur->bc_mp = mp;
685 	cur->bc_maxlevels = maxlevels;
686 	cur->bc_cache = cache;
687 
688 	return cur;
689 }
690 
691 int __init xfs_btree_init_cur_caches(void);
692 void xfs_btree_destroy_cur_caches(void);
693 
694 int xfs_btree_goto_left_edge(struct xfs_btree_cur *cur);
695 
696 /* Does this level of the cursor point to the inode root (and not a block)? */
697 static inline bool
xfs_btree_at_iroot(const struct xfs_btree_cur * cur,int level)698 xfs_btree_at_iroot(
699 	const struct xfs_btree_cur	*cur,
700 	int				level)
701 {
702 	return cur->bc_ops->type == XFS_BTREE_TYPE_INODE &&
703 	       level == cur->bc_nlevels - 1;
704 }
705 
706 int xfs_btree_alloc_metafile_block(struct xfs_btree_cur *cur,
707 		const union xfs_btree_ptr *start, union xfs_btree_ptr *newp,
708 		int *stat);
709 int xfs_btree_free_metafile_block(struct xfs_btree_cur *cur,
710 		struct xfs_buf *bp);
711 
712 #endif	/* __XFS_BTREE_H__ */
713