xref: /freebsd/sys/dev/mem/memutil.c (revision 911f0260390e18cf85f3dbf2c719b593efdc1e3c)
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 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/lock.h>
35 #include <sys/malloc.h>
36 #include <sys/memrange.h>
37 #include <sys/rwlock.h>
38 #include <sys/systm.h>
39 
40 static struct rwlock	mr_lock;
41 
42 /*
43  * Implementation-neutral, kernel-callable functions for manipulating
44  * memory range attributes.
45  */
46 void
47 mem_range_init(void)
48 {
49 
50 	if (mem_range_softc.mr_op == NULL)
51 		return;
52 	rw_init(&mr_lock, "memrange");
53 	mem_range_softc.mr_op->init(&mem_range_softc);
54 }
55 
56 void
57 mem_range_destroy(void)
58 {
59 
60 	if (mem_range_softc.mr_op == NULL)
61 		return;
62 	rw_destroy(&mr_lock);
63 }
64 
65 int
66 mem_range_attr_get(struct mem_range_desc *mrd, int *arg)
67 {
68 	int nd;
69 
70 	if (mem_range_softc.mr_op == NULL)
71 		return (EOPNOTSUPP);
72 	nd = *arg;
73 	rw_rlock(&mr_lock);
74 	if (nd == 0)
75 		*arg = mem_range_softc.mr_ndesc;
76 	else
77 		bcopy(mem_range_softc.mr_desc, mrd, nd * sizeof(*mrd));
78 	rw_runlock(&mr_lock);
79 	return (0);
80 }
81 
82 int
83 mem_range_attr_set(struct mem_range_desc *mrd, int *arg)
84 {
85 	int ret;
86 
87 	if (mem_range_softc.mr_op == NULL)
88 		return (EOPNOTSUPP);
89 	rw_wlock(&mr_lock);
90 	ret = mem_range_softc.mr_op->set(&mem_range_softc, mrd, arg);
91 	rw_wunlock(&mr_lock);
92 	return (ret);
93 }
94