xref: /freebsd/sys/sys/rangeset.h (revision 8aa2cd9d13d4b1a81ac313e9d3e214ec3a928430)
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 
31 #ifndef	_SYS_RANGESET_H
32 #define	_SYS_RANGESET_H
33 
34 #ifdef	_KERNEL
35 
36 #include <sys/_rangeset.h>
37 
38 typedef bool (*rs_pred_t)(void *ctx, void *r);
39 
40 /*
41  * This structure must be embedded at the start of the rangeset element.
42  */
43 struct rs_el {
44 	uint64_t	re_start;	/* pctrie key */
45 	uint64_t	re_end;
46 };
47 
48 void	rangeset_init(struct rangeset *rs, rs_dup_data_t dup_data,
49 	    rs_free_data_t free_data, void *rs_data_ctx, u_int alloc_flags);
50 void	rangeset_fini(struct rangeset *rs);
51 
52 bool	rangeset_check_empty(struct rangeset *rs, uint64_t start,
53 	    uint64_t end);
54 
55 /*
56  * r point to the app data with struct rs_el at the beginning.
57  */
58 int	rangeset_insert(struct rangeset *rs, uint64_t start, uint64_t end,
59 	    void *r);
60 
61 /*
62  * Guarantees that on error the rangeset is not modified.  Remove
63  * might need to split element if its start/end completely cover the
64  * removed range, in which case ENOMEM might be returned.
65  */
66 void	rangeset_remove_all(struct rangeset *rs);
67 int	rangeset_remove(struct rangeset *rs, uint64_t start, uint64_t end);
68 int	rangeset_remove_pred(struct rangeset *rs, uint64_t start,
69 	    uint64_t end, rs_pred_t pred);
70 
71 /*
72  * Finds the range that contains place, if any.
73  */
74 void	*rangeset_containing(struct rangeset *rs, uint64_t place);
75 
76 /*
77  * Report whether no range begins between start and end.
78  */
79 bool	rangeset_empty(struct rangeset *rs, uint64_t start, uint64_t end);
80 
81 /*
82  * Finds the range that begins at place, if any.
83  */
84 void	*rangeset_beginning(struct rangeset *rs, uint64_t place);
85 
86 /*
87  * Copies src_rs entries into dst_rs.  dst_rs must be empty.
88  * Leaves dst_rs empty on failure.
89  */
90 int	rangeset_copy(struct rangeset *dst_rs, struct rangeset *src_rs);
91 
92 #endif
93 
94 #endif
95