xref: /freebsd/sys/dev/mem/memutil.c (revision 734e82fe33aa764367791a7d603b383996c6b40b)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2004 Mark R V Murray
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer
12  *    in this position and unchanged.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 #include <sys/param.h>
31 #include <sys/kernel.h>
32 #include <sys/lock.h>
33 #include <sys/malloc.h>
34 #include <sys/memrange.h>
35 #include <sys/rwlock.h>
36 #include <sys/systm.h>
37 
38 static struct rwlock	mr_lock;
39 
40 /*
41  * Implementation-neutral, kernel-callable functions for manipulating
42  * memory range attributes.
43  */
44 void
45 mem_range_init(void)
46 {
47 
48 	if (mem_range_softc.mr_op == NULL)
49 		return;
50 	rw_init(&mr_lock, "memrange");
51 	mem_range_softc.mr_op->init(&mem_range_softc);
52 }
53 
54 void
55 mem_range_destroy(void)
56 {
57 
58 	if (mem_range_softc.mr_op == NULL)
59 		return;
60 	rw_destroy(&mr_lock);
61 }
62 
63 int
64 mem_range_attr_get(struct mem_range_desc *mrd, int *arg)
65 {
66 	int nd;
67 
68 	if (mem_range_softc.mr_op == NULL)
69 		return (EOPNOTSUPP);
70 	nd = *arg;
71 	rw_rlock(&mr_lock);
72 	if (nd == 0)
73 		*arg = mem_range_softc.mr_ndesc;
74 	else
75 		bcopy(mem_range_softc.mr_desc, mrd, nd * sizeof(*mrd));
76 	rw_runlock(&mr_lock);
77 	return (0);
78 }
79 
80 int
81 mem_range_attr_set(struct mem_range_desc *mrd, int *arg)
82 {
83 	int ret;
84 
85 	if (mem_range_softc.mr_op == NULL)
86 		return (EOPNOTSUPP);
87 	rw_wlock(&mr_lock);
88 	ret = mem_range_softc.mr_op->set(&mem_range_softc, mrd, arg);
89 	rw_wunlock(&mr_lock);
90 	return (ret);
91 }
92