xref: /freebsd/sys/sys/rangeset.h (revision bdd1243d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019 The FreeBSD Foundation
5  *
6  * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
7  * under sponsorship from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #ifndef	_SYS_RANGESET_H
34 #define	_SYS_RANGESET_H
35 
36 #ifdef	_KERNEL
37 
38 #include <sys/_rangeset.h>
39 
40 typedef bool (*rs_pred_t)(void *ctx, void *r);
41 
42 /*
43  * This structure must be embedded at the start of the rangeset element.
44  */
45 struct rs_el {
46 	uint64_t	re_start;	/* pctrie key */
47 	uint64_t	re_end;
48 };
49 
50 void	rangeset_init(struct rangeset *rs, rs_dup_data_t dup_data,
51 	    rs_free_data_t free_data, void *rs_data_ctx, u_int alloc_flags);
52 void	rangeset_fini(struct rangeset *rs);
53 
54 bool	rangeset_check_empty(struct rangeset *rs, uint64_t start,
55 	    uint64_t end);
56 
57 /*
58  * r point to the app data with struct rs_el at the beginning.
59  */
60 int	rangeset_insert(struct rangeset *rs, uint64_t start, uint64_t end,
61 	    void *r);
62 
63 /*
64  * Guarantees that on error the rangeset is not modified.  Remove
65  * might need to split element if its start/end completely cover the
66  * removed range, in which case ENOMEM might be returned.
67  */
68 void	rangeset_remove_all(struct rangeset *rs);
69 int	rangeset_remove(struct rangeset *rs, uint64_t start, uint64_t end);
70 int	rangeset_remove_pred(struct rangeset *rs, uint64_t start,
71 	    uint64_t end, rs_pred_t pred);
72 
73 /*
74  * Really returns the pointer to the data with struct rs_el embedded
75  * at the beginning.
76  */
77 void	*rangeset_lookup(struct rangeset *rs, uint64_t place);
78 
79 /*
80  * Copies src_rs entries into dst_rs.  dst_rs must be empty.
81  * Leaves dst_rs empty on failure.
82  */
83 int	rangeset_copy(struct rangeset *dst_rs, struct rangeset *src_rs);
84 
85 #endif
86 
87 #endif
88