xref: /freebsd/sys/contrib/openzfs/include/sys/range_tree.h (revision 22649d4dba730d46244fd2dff4fd174903c8379f)
1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3  * This file and its contents are supplied under the terms of the
4  * Common Development and Distribution License ("CDDL"), version 1.0.
5  * You may only use this file in accordance with the terms of version
6  * 1.0 of the CDDL.
7  *
8  * A full copy of the text of the CDDL should have accompanied this
9  * source.  A copy of the CDDL is also available via the Internet at
10  * https://opensource.org/license/CDDL-1.0.
11  */
12 /*
13  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
14  * Use is subject to license terms.
15  */
16 
17 /*
18  * Copyright (c) 2013, 2019 by Delphix. All rights reserved.
19  */
20 
21 #ifndef _SYS_RANGE_TREE_H
22 #define	_SYS_RANGE_TREE_H
23 
24 #include <sys/btree.h>
25 #include <sys/dmu.h>
26 
27 #ifdef	__cplusplus
28 extern "C" {
29 #endif
30 
31 #define	ZFS_RANGE_TREE_HISTOGRAM_SIZE	64
32 
33 typedef struct zfs_range_tree_ops zfs_range_tree_ops_t;
34 
35 typedef enum zfs_range_seg_type {
36 	ZFS_RANGE_SEG32,
37 	ZFS_RANGE_SEG64,
38 	ZFS_RANGE_SEG_GAP,
39 	ZFS_RANGE_SEG_NUM_TYPES,
40 } zfs_range_seg_type_t;
41 
42 #define	ZFS_RT_NAME(rt)		(((rt)->rt_name != NULL) ? (rt)->rt_name : "")
43 #define	ZFS_RT_F_DYN_NAME	(1ULL << 0) /* if rt_name must be freed */
44 
45 /*
46  * Note: the range_tree may not be accessed concurrently; consumers
47  * must provide external locking if required.
48  */
49 typedef struct zfs_range_tree {
50 	zfs_btree_t	rt_root;	/* offset-ordered segment b-tree */
51 	uint64_t	rt_space;	/* sum of all segments in the map */
52 	zfs_range_seg_type_t rt_type;	/* type of zfs_range_seg_t in use */
53 	/*
54 	 * All data that is stored in the range tree must have a start higher
55 	 * than or equal to rt_start, and all sizes and offsets must be
56 	 * multiples of 1 << rt_shift.
57 	 */
58 	uint8_t		rt_shift;
59 	uint64_t	rt_start;
60 	const zfs_range_tree_ops_t *rt_ops;
61 	void		*rt_arg;
62 	uint64_t	rt_gap;		/* allowable inter-segment gap */
63 
64 	uint64_t	rt_flags;
65 	const char	*rt_name;	/* details for debugging */
66 
67 	/*
68 	 * The rt_histogram maintains a histogram of ranges. Each bucket,
69 	 * rt_histogram[i], contains the number of ranges whose size is:
70 	 * 2^i <= size of range in bytes < 2^(i+1)
71 	 */
72 	uint64_t	rt_histogram[ZFS_RANGE_TREE_HISTOGRAM_SIZE];
73 } zfs_range_tree_t;
74 
75 typedef struct zfs_range_seg32 {
76 	uint32_t	rs_start;	/* starting offset of this segment */
77 	uint32_t	rs_end;		/* ending offset (non-inclusive) */
78 } zfs_range_seg32_t;
79 
80 /*
81  * Extremely large metaslabs, vdev-wide trees, and dnode-wide trees may
82  * require 64-bit integers for ranges.
83  */
84 typedef struct zfs_range_seg64 {
85 	uint64_t	rs_start;	/* starting offset of this segment */
86 	uint64_t	rs_end;		/* ending offset (non-inclusive) */
87 } zfs_range_seg64_t;
88 
89 typedef struct zfs_range_seg_gap {
90 	uint64_t	rs_start;	/* starting offset of this segment */
91 	uint64_t	rs_end;		/* ending offset (non-inclusive) */
92 	uint64_t	rs_fill;	/* actual fill if gap mode is on */
93 } zfs_range_seg_gap_t;
94 
95 /*
96  * This type needs to be the largest of the range segs, since it will be stack
97  * allocated and then cast the actual type to do tree operations.
98  */
99 typedef zfs_range_seg_gap_t zfs_range_seg_max_t;
100 
101 /*
102  * This is just for clarity of code purposes, so we can make it clear that a
103  * pointer is to a range seg of some type; when we need to do the actual math,
104  * we'll figure out the real type.
105  */
106 typedef void zfs_range_seg_t;
107 
108 struct zfs_range_tree_ops {
109 	void    (*rtop_create)(zfs_range_tree_t *rt, void *arg);
110 	void    (*rtop_destroy)(zfs_range_tree_t *rt, void *arg);
111 	void	(*rtop_add)(zfs_range_tree_t *rt, void *rs, void *arg);
112 	void    (*rtop_remove)(zfs_range_tree_t *rt, void *rs, void *arg);
113 	void	(*rtop_vacate)(zfs_range_tree_t *rt, void *arg);
114 };
115 
116 static inline uint64_t
zfs_rs_get_start_raw(const zfs_range_seg_t * rs,const zfs_range_tree_t * rt)117 zfs_rs_get_start_raw(const zfs_range_seg_t *rs, const zfs_range_tree_t *rt)
118 {
119 	ASSERT3U(rt->rt_type, <=, ZFS_RANGE_SEG_NUM_TYPES);
120 	switch (rt->rt_type) {
121 	case ZFS_RANGE_SEG32:
122 		return (((const zfs_range_seg32_t *)rs)->rs_start);
123 	case ZFS_RANGE_SEG64:
124 		return (((const zfs_range_seg64_t *)rs)->rs_start);
125 	case ZFS_RANGE_SEG_GAP:
126 		return (((const zfs_range_seg_gap_t *)rs)->rs_start);
127 	default:
128 		VERIFY(0);
129 		return (0);
130 	}
131 }
132 
133 static inline uint64_t
zfs_rs_get_end_raw(const zfs_range_seg_t * rs,const zfs_range_tree_t * rt)134 zfs_rs_get_end_raw(const zfs_range_seg_t *rs, const zfs_range_tree_t *rt)
135 {
136 	ASSERT3U(rt->rt_type, <=, ZFS_RANGE_SEG_NUM_TYPES);
137 	switch (rt->rt_type) {
138 	case ZFS_RANGE_SEG32:
139 		return (((const zfs_range_seg32_t *)rs)->rs_end);
140 	case ZFS_RANGE_SEG64:
141 		return (((const zfs_range_seg64_t *)rs)->rs_end);
142 	case ZFS_RANGE_SEG_GAP:
143 		return (((const zfs_range_seg_gap_t *)rs)->rs_end);
144 	default:
145 		VERIFY(0);
146 		return (0);
147 	}
148 }
149 
150 static inline uint64_t
zfs_rs_get_fill_raw(const zfs_range_seg_t * rs,const zfs_range_tree_t * rt)151 zfs_rs_get_fill_raw(const zfs_range_seg_t *rs, const zfs_range_tree_t *rt)
152 {
153 	ASSERT3U(rt->rt_type, <=, ZFS_RANGE_SEG_NUM_TYPES);
154 	switch (rt->rt_type) {
155 	case ZFS_RANGE_SEG32: {
156 		const zfs_range_seg32_t *r32 = (const zfs_range_seg32_t *)rs;
157 		return (r32->rs_end - r32->rs_start);
158 	}
159 	case ZFS_RANGE_SEG64: {
160 		const zfs_range_seg64_t *r64 = (const zfs_range_seg64_t *)rs;
161 		return (r64->rs_end - r64->rs_start);
162 	}
163 	case ZFS_RANGE_SEG_GAP:
164 		return (((const zfs_range_seg_gap_t *)rs)->rs_fill);
165 	default:
166 		VERIFY(0);
167 		return (0);
168 	}
169 
170 }
171 
172 static inline uint64_t
zfs_rs_get_start(const zfs_range_seg_t * rs,const zfs_range_tree_t * rt)173 zfs_rs_get_start(const zfs_range_seg_t *rs, const zfs_range_tree_t *rt)
174 {
175 	return ((zfs_rs_get_start_raw(rs, rt) << rt->rt_shift) + rt->rt_start);
176 }
177 
178 static inline uint64_t
zfs_rs_get_end(const zfs_range_seg_t * rs,const zfs_range_tree_t * rt)179 zfs_rs_get_end(const zfs_range_seg_t *rs, const zfs_range_tree_t *rt)
180 {
181 	return ((zfs_rs_get_end_raw(rs, rt) << rt->rt_shift) + rt->rt_start);
182 }
183 
184 static inline uint64_t
zfs_rs_get_fill(const zfs_range_seg_t * rs,const zfs_range_tree_t * rt)185 zfs_rs_get_fill(const zfs_range_seg_t *rs, const zfs_range_tree_t *rt)
186 {
187 	return (zfs_rs_get_fill_raw(rs, rt) << rt->rt_shift);
188 }
189 
190 static inline void
zfs_rs_set_start_raw(zfs_range_seg_t * rs,zfs_range_tree_t * rt,uint64_t start)191 zfs_rs_set_start_raw(zfs_range_seg_t *rs, zfs_range_tree_t *rt, uint64_t start)
192 {
193 	ASSERT3U(rt->rt_type, <=, ZFS_RANGE_SEG_NUM_TYPES);
194 	switch (rt->rt_type) {
195 	case ZFS_RANGE_SEG32:
196 		ASSERT3U(start, <=, UINT32_MAX);
197 		((zfs_range_seg32_t *)rs)->rs_start = (uint32_t)start;
198 		break;
199 	case ZFS_RANGE_SEG64:
200 		((zfs_range_seg64_t *)rs)->rs_start = start;
201 		break;
202 	case ZFS_RANGE_SEG_GAP:
203 		((zfs_range_seg_gap_t *)rs)->rs_start = start;
204 		break;
205 	default:
206 		VERIFY(0);
207 	}
208 }
209 
210 static inline void
zfs_rs_set_end_raw(zfs_range_seg_t * rs,zfs_range_tree_t * rt,uint64_t end)211 zfs_rs_set_end_raw(zfs_range_seg_t *rs, zfs_range_tree_t *rt, uint64_t end)
212 {
213 	ASSERT3U(rt->rt_type, <=, ZFS_RANGE_SEG_NUM_TYPES);
214 	switch (rt->rt_type) {
215 	case ZFS_RANGE_SEG32:
216 		ASSERT3U(end, <=, UINT32_MAX);
217 		((zfs_range_seg32_t *)rs)->rs_end = (uint32_t)end;
218 		break;
219 	case ZFS_RANGE_SEG64:
220 		((zfs_range_seg64_t *)rs)->rs_end = end;
221 		break;
222 	case ZFS_RANGE_SEG_GAP:
223 		((zfs_range_seg_gap_t *)rs)->rs_end = end;
224 		break;
225 	default:
226 		VERIFY(0);
227 	}
228 }
229 
230 static inline void
zfs_rs_set_fill_raw(zfs_range_seg_t * rs,zfs_range_tree_t * rt,uint64_t fill)231 zfs_rs_set_fill_raw(zfs_range_seg_t *rs, zfs_range_tree_t *rt, uint64_t fill)
232 {
233 	ASSERT3U(rt->rt_type, <=, ZFS_RANGE_SEG_NUM_TYPES);
234 	switch (rt->rt_type) {
235 	case ZFS_RANGE_SEG32:
236 		/* fall through */
237 	case ZFS_RANGE_SEG64:
238 		ASSERT3U(fill, ==, zfs_rs_get_end_raw(rs, rt) -
239 		    zfs_rs_get_start_raw(rs, rt));
240 		break;
241 	case ZFS_RANGE_SEG_GAP:
242 		((zfs_range_seg_gap_t *)rs)->rs_fill = fill;
243 		break;
244 	default:
245 		VERIFY(0);
246 	}
247 }
248 
249 static inline void
zfs_rs_set_start(zfs_range_seg_t * rs,zfs_range_tree_t * rt,uint64_t start)250 zfs_rs_set_start(zfs_range_seg_t *rs, zfs_range_tree_t *rt, uint64_t start)
251 {
252 	ASSERT3U(start, >=, rt->rt_start);
253 	ASSERT(IS_P2ALIGNED(start, 1ULL << rt->rt_shift));
254 	zfs_rs_set_start_raw(rs, rt, (start - rt->rt_start) >> rt->rt_shift);
255 }
256 
257 static inline void
zfs_rs_set_end(zfs_range_seg_t * rs,zfs_range_tree_t * rt,uint64_t end)258 zfs_rs_set_end(zfs_range_seg_t *rs, zfs_range_tree_t *rt, uint64_t end)
259 {
260 	ASSERT3U(end, >=, rt->rt_start);
261 	ASSERT(IS_P2ALIGNED(end, 1ULL << rt->rt_shift));
262 	zfs_rs_set_end_raw(rs, rt, (end - rt->rt_start) >> rt->rt_shift);
263 }
264 
265 static inline void
zfs_rs_set_fill(zfs_range_seg_t * rs,zfs_range_tree_t * rt,uint64_t fill)266 zfs_rs_set_fill(zfs_range_seg_t *rs, zfs_range_tree_t *rt, uint64_t fill)
267 {
268 	ASSERT(IS_P2ALIGNED(fill, 1ULL << rt->rt_shift));
269 	zfs_rs_set_fill_raw(rs, rt, fill >> rt->rt_shift);
270 }
271 
272 typedef void zfs_range_tree_func_t(void *arg, uint64_t start, uint64_t size);
273 
274 zfs_range_tree_t *zfs_range_tree_create_gap(const zfs_range_tree_ops_t *ops,
275     zfs_range_seg_type_t type, void *arg, uint64_t start, uint64_t shift,
276     uint64_t gap);
277 zfs_range_tree_t *zfs_range_tree_create(const zfs_range_tree_ops_t *ops,
278     zfs_range_seg_type_t type, void *arg, uint64_t start, uint64_t shift);
279 zfs_range_tree_t *zfs_range_tree_create_flags(const zfs_range_tree_ops_t *ops,
280     zfs_range_seg_type_t type, void *arg, uint64_t start, uint64_t shift,
281     uint64_t flags, const char *name);
282 void zfs_range_tree_destroy(zfs_range_tree_t *rt);
283 boolean_t zfs_range_tree_contains(zfs_range_tree_t *rt, uint64_t start,
284     uint64_t size);
285 zfs_range_seg_t *zfs_range_tree_find(zfs_range_tree_t *rt, uint64_t start,
286     uint64_t size);
287 boolean_t zfs_range_tree_find_in(zfs_range_tree_t *rt, uint64_t start,
288     uint64_t size, uint64_t *ostart, uint64_t *osize);
289 void zfs_range_tree_verify_not_present(zfs_range_tree_t *rt,
290     uint64_t start, uint64_t size);
291 void zfs_range_tree_resize_segment(zfs_range_tree_t *rt, zfs_range_seg_t *rs,
292     uint64_t newstart, uint64_t newsize);
293 uint64_t zfs_range_tree_space(zfs_range_tree_t *rt);
294 uint64_t zfs_range_tree_numsegs(zfs_range_tree_t *rt);
295 boolean_t zfs_range_tree_is_empty(zfs_range_tree_t *rt);
296 void zfs_range_tree_swap(zfs_range_tree_t **rtsrc, zfs_range_tree_t **rtdst);
297 void zfs_range_tree_stat_verify(zfs_range_tree_t *rt);
298 uint64_t zfs_range_tree_min(zfs_range_tree_t *rt);
299 uint64_t zfs_range_tree_max(zfs_range_tree_t *rt);
300 uint64_t zfs_range_tree_span(zfs_range_tree_t *rt);
301 
302 void zfs_range_tree_add(void *arg, uint64_t start, uint64_t size);
303 void zfs_range_tree_remove(void *arg, uint64_t start, uint64_t size);
304 void zfs_range_tree_remove_fill(zfs_range_tree_t *rt, uint64_t start,
305     uint64_t size);
306 void zfs_range_tree_adjust_fill(zfs_range_tree_t *rt, zfs_range_seg_t *rs,
307     int64_t delta);
308 void zfs_range_tree_clear(zfs_range_tree_t *rt, uint64_t start, uint64_t size);
309 
310 void zfs_range_tree_vacate(zfs_range_tree_t *rt, zfs_range_tree_func_t *func,
311     void *arg);
312 void zfs_range_tree_walk(zfs_range_tree_t *rt, zfs_range_tree_func_t *func,
313     void *arg);
314 zfs_range_seg_t *zfs_range_tree_first(zfs_range_tree_t *rt);
315 
316 void zfs_range_tree_remove_xor_add_segment(uint64_t start, uint64_t end,
317     zfs_range_tree_t *removefrom, zfs_range_tree_t *addto);
318 void zfs_range_tree_remove_xor_add(zfs_range_tree_t *rt,
319     zfs_range_tree_t *removefrom, zfs_range_tree_t *addto);
320 
321 #ifdef	__cplusplus
322 }
323 #endif
324 
325 #endif	/* _SYS_RANGE_TREE_H */
326