1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26/*
27 * Copyright (c) 2013, 2019 by Delphix. All rights reserved.
28 */
29
30#ifndef _SYS_RANGE_TREE_H
31#define	_SYS_RANGE_TREE_H
32
33#include <sys/btree.h>
34#include <sys/dmu.h>
35
36#ifdef	__cplusplus
37extern "C" {
38#endif
39
40#define	RANGE_TREE_HISTOGRAM_SIZE	64
41
42typedef struct range_tree_ops range_tree_ops_t;
43
44typedef enum range_seg_type {
45	RANGE_SEG32,
46	RANGE_SEG64,
47	RANGE_SEG_GAP,
48	RANGE_SEG_NUM_TYPES,
49} range_seg_type_t;
50
51/*
52 * Note: the range_tree may not be accessed concurrently; consumers
53 * must provide external locking if required.
54 */
55typedef struct range_tree {
56	zfs_btree_t	rt_root;	/* offset-ordered segment b-tree */
57	uint64_t	rt_space;	/* sum of all segments in the map */
58	range_seg_type_t rt_type;	/* type of range_seg_t in use */
59	/*
60	 * All data that is stored in the range tree must have a start higher
61	 * than or equal to rt_start, and all sizes and offsets must be
62	 * multiples of 1 << rt_shift.
63	 */
64	uint8_t		rt_shift;
65	uint64_t	rt_start;
66	range_tree_ops_t *rt_ops;
67
68	/* rt_btree_compare should only be set if rt_arg is a b-tree */
69	void		*rt_arg;
70	int (*rt_btree_compare)(const void *, const void *);
71
72	uint64_t	rt_gap;		/* allowable inter-segment gap */
73
74	/*
75	 * The rt_histogram maintains a histogram of ranges. Each bucket,
76	 * rt_histogram[i], contains the number of ranges whose size is:
77	 * 2^i <= size of range in bytes < 2^(i+1)
78	 */
79	uint64_t	rt_histogram[RANGE_TREE_HISTOGRAM_SIZE];
80} range_tree_t;
81
82typedef struct range_seg32 {
83	uint32_t	rs_start;	/* starting offset of this segment */
84	uint32_t	rs_end;		/* ending offset (non-inclusive) */
85} range_seg32_t;
86
87/*
88 * Extremely large metaslabs, vdev-wide trees, and dnode-wide trees may
89 * require 64-bit integers for ranges.
90 */
91typedef struct range_seg64 {
92	uint64_t	rs_start;	/* starting offset of this segment */
93	uint64_t	rs_end;		/* ending offset (non-inclusive) */
94} range_seg64_t;
95
96typedef struct range_seg_gap {
97	uint64_t	rs_start;	/* starting offset of this segment */
98	uint64_t	rs_end;		/* ending offset (non-inclusive) */
99	uint64_t	rs_fill;	/* actual fill if gap mode is on */
100} range_seg_gap_t;
101
102/*
103 * This type needs to be the largest of the range segs, since it will be stack
104 * allocated and then cast the actual type to do tree operations.
105 */
106typedef range_seg_gap_t range_seg_max_t;
107
108/*
109 * This is just for clarity of code purposes, so we can make it clear that a
110 * pointer is to a range seg of some type; when we need to do the actual math,
111 * we'll figure out the real type.
112 */
113typedef void range_seg_t;
114
115struct range_tree_ops {
116	void    (*rtop_create)(range_tree_t *rt, void *arg);
117	void    (*rtop_destroy)(range_tree_t *rt, void *arg);
118	void	(*rtop_add)(range_tree_t *rt, void *rs, void *arg);
119	void    (*rtop_remove)(range_tree_t *rt, void *rs, void *arg);
120	void	(*rtop_vacate)(range_tree_t *rt, void *arg);
121};
122
123static inline uint64_t
124rs_get_start_raw(const range_seg_t *rs, const range_tree_t *rt)
125{
126	ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
127	switch (rt->rt_type) {
128	case RANGE_SEG32:
129		return (((const range_seg32_t *)rs)->rs_start);
130	case RANGE_SEG64:
131		return (((const range_seg64_t *)rs)->rs_start);
132	case RANGE_SEG_GAP:
133		return (((const range_seg_gap_t *)rs)->rs_start);
134	default:
135		VERIFY(0);
136		return (0);
137	}
138}
139
140static inline uint64_t
141rs_get_end_raw(const range_seg_t *rs, const range_tree_t *rt)
142{
143	ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
144	switch (rt->rt_type) {
145	case RANGE_SEG32:
146		return (((const range_seg32_t *)rs)->rs_end);
147	case RANGE_SEG64:
148		return (((const range_seg64_t *)rs)->rs_end);
149	case RANGE_SEG_GAP:
150		return (((const range_seg_gap_t *)rs)->rs_end);
151	default:
152		VERIFY(0);
153		return (0);
154	}
155}
156
157static inline uint64_t
158rs_get_fill_raw(const range_seg_t *rs, const range_tree_t *rt)
159{
160	ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
161	switch (rt->rt_type) {
162	case RANGE_SEG32: {
163		const range_seg32_t *r32 = rs;
164		return (r32->rs_end - r32->rs_start);
165	}
166	case RANGE_SEG64: {
167		const range_seg64_t *r64 = rs;
168		return (r64->rs_end - r64->rs_start);
169	}
170	case RANGE_SEG_GAP:
171		return (((range_seg_gap_t *)rs)->rs_fill);
172	default:
173		VERIFY(0);
174		return (0);
175	}
176
177}
178
179static inline uint64_t
180rs_get_start(const range_seg_t *rs, const range_tree_t *rt)
181{
182	return ((rs_get_start_raw(rs, rt) << rt->rt_shift) + rt->rt_start);
183}
184
185static inline uint64_t
186rs_get_end(const range_seg_t *rs, const range_tree_t *rt)
187{
188	return ((rs_get_end_raw(rs, rt) << rt->rt_shift) + rt->rt_start);
189}
190
191static inline uint64_t
192rs_get_fill(const range_seg_t *rs, const range_tree_t *rt)
193{
194	return (rs_get_fill_raw(rs, rt) << rt->rt_shift);
195}
196
197static inline void
198rs_set_start_raw(range_seg_t *rs, range_tree_t *rt, uint64_t start)
199{
200	ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
201	switch (rt->rt_type) {
202	case RANGE_SEG32:
203		ASSERT3U(start, <=, UINT32_MAX);
204		((range_seg32_t *)rs)->rs_start = (uint32_t)start;
205		break;
206	case RANGE_SEG64:
207		((range_seg64_t *)rs)->rs_start = start;
208		break;
209	case RANGE_SEG_GAP:
210		((range_seg_gap_t *)rs)->rs_start = start;
211		break;
212	default:
213		VERIFY(0);
214	}
215}
216
217static inline void
218rs_set_end_raw(range_seg_t *rs, range_tree_t *rt, uint64_t end)
219{
220	ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
221	switch (rt->rt_type) {
222	case RANGE_SEG32:
223		ASSERT3U(end, <=, UINT32_MAX);
224		((range_seg32_t *)rs)->rs_end = (uint32_t)end;
225		break;
226	case RANGE_SEG64:
227		((range_seg64_t *)rs)->rs_end = end;
228		break;
229	case RANGE_SEG_GAP:
230		((range_seg_gap_t *)rs)->rs_end = end;
231		break;
232	default:
233		VERIFY(0);
234	}
235}
236
237static inline void
238rs_set_fill_raw(range_seg_t *rs, range_tree_t *rt, uint64_t fill)
239{
240	ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
241	switch (rt->rt_type) {
242	case RANGE_SEG32:
243		/* fall through */
244	case RANGE_SEG64:
245		ASSERT3U(fill, ==, rs_get_end_raw(rs, rt) - rs_get_start_raw(rs,
246		    rt));
247		break;
248	case RANGE_SEG_GAP:
249		((range_seg_gap_t *)rs)->rs_fill = fill;
250		break;
251	default:
252		VERIFY(0);
253	}
254}
255
256static inline void
257rs_set_start(range_seg_t *rs, range_tree_t *rt, uint64_t start)
258{
259	ASSERT3U(start, >=, rt->rt_start);
260	ASSERT(IS_P2ALIGNED(start, 1ULL << rt->rt_shift));
261	rs_set_start_raw(rs, rt, (start - rt->rt_start) >> rt->rt_shift);
262}
263
264static inline void
265rs_set_end(range_seg_t *rs, range_tree_t *rt, uint64_t end)
266{
267	ASSERT3U(end, >=, rt->rt_start);
268	ASSERT(IS_P2ALIGNED(end, 1ULL << rt->rt_shift));
269	rs_set_end_raw(rs, rt, (end - rt->rt_start) >> rt->rt_shift);
270}
271
272static inline void
273rs_set_fill(range_seg_t *rs, range_tree_t *rt, uint64_t fill)
274{
275	ASSERT(IS_P2ALIGNED(fill, 1ULL << rt->rt_shift));
276	rs_set_fill_raw(rs, rt, fill >> rt->rt_shift);
277}
278
279typedef void range_tree_func_t(void *arg, uint64_t start, uint64_t size);
280
281range_tree_t *range_tree_create_impl(range_tree_ops_t *ops,
282    range_seg_type_t type, void *arg, uint64_t start, uint64_t shift,
283    int (*zfs_btree_compare) (const void *, const void *), uint64_t gap);
284range_tree_t *range_tree_create(range_tree_ops_t *ops, range_seg_type_t type,
285    void *arg, uint64_t start, uint64_t shift);
286void range_tree_destroy(range_tree_t *rt);
287boolean_t range_tree_contains(range_tree_t *rt, uint64_t start, uint64_t size);
288range_seg_t *range_tree_find(range_tree_t *rt, uint64_t start, uint64_t size);
289boolean_t range_tree_find_in(range_tree_t *rt, uint64_t start, uint64_t size,
290    uint64_t *ostart, uint64_t *osize);
291void range_tree_verify_not_present(range_tree_t *rt,
292    uint64_t start, uint64_t size);
293void range_tree_resize_segment(range_tree_t *rt, range_seg_t *rs,
294    uint64_t newstart, uint64_t newsize);
295uint64_t range_tree_space(range_tree_t *rt);
296uint64_t range_tree_numsegs(range_tree_t *rt);
297boolean_t range_tree_is_empty(range_tree_t *rt);
298void range_tree_swap(range_tree_t **rtsrc, range_tree_t **rtdst);
299void range_tree_stat_verify(range_tree_t *rt);
300uint64_t range_tree_min(range_tree_t *rt);
301uint64_t range_tree_max(range_tree_t *rt);
302uint64_t range_tree_span(range_tree_t *rt);
303
304void range_tree_add(void *arg, uint64_t start, uint64_t size);
305void range_tree_remove(void *arg, uint64_t start, uint64_t size);
306void range_tree_remove_fill(range_tree_t *rt, uint64_t start, uint64_t size);
307void range_tree_adjust_fill(range_tree_t *rt, range_seg_t *rs, int64_t delta);
308void range_tree_clear(range_tree_t *rt, uint64_t start, uint64_t size);
309
310void range_tree_vacate(range_tree_t *rt, range_tree_func_t *func, void *arg);
311void range_tree_walk(range_tree_t *rt, range_tree_func_t *func, void *arg);
312range_seg_t *range_tree_first(range_tree_t *rt);
313
314void range_tree_remove_xor_add_segment(uint64_t start, uint64_t end,
315    range_tree_t *removefrom, range_tree_t *addto);
316void range_tree_remove_xor_add(range_tree_t *rt, range_tree_t *removefrom,
317    range_tree_t *addto);
318
319void rt_btree_create(range_tree_t *rt, void *arg);
320void rt_btree_destroy(range_tree_t *rt, void *arg);
321void rt_btree_add(range_tree_t *rt, range_seg_t *rs, void *arg);
322void rt_btree_remove(range_tree_t *rt, range_seg_t *rs, void *arg);
323void rt_btree_vacate(range_tree_t *rt, void *arg);
324extern range_tree_ops_t rt_btree_ops;
325
326#ifdef	__cplusplus
327}
328#endif
329
330#endif	/* _SYS_RANGE_TREE_H */
331