xref: /freebsd/sys/i386/linux/linux_copyout.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2018 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 #include <sys/param.h>
32 #include <sys/imgact.h>
33 #include <sys/lock.h>
34 #include <sys/sx.h>
35 
36 #include <vm/vm.h>
37 #include <vm/vm_param.h>
38 #include <vm/vm_extern.h>
39 #include <vm/pmap.h>
40 
41 #include <machine/atomic.h>
42 #include <machine/md_var.h>
43 
44 #include <i386/linux/linux.h>
45 #include <compat/linux/linux_emul.h>
46 #include <compat/linux/linux_futex.h>
47 
48 struct futex_st0 {
49 	int oparg;
50 	int *oldval;
51 };
52 
53 static void
54 futex_xchgl_slow0(vm_offset_t kva, void *arg)
55 {
56 	struct futex_st0 *st;
57 
58 	st = arg;
59 	*st->oldval = atomic_swap_int((int *)kva, st->oparg);
60 }
61 
62 int
63 futex_xchgl(int oparg, uint32_t *uaddr, int *oldval)
64 {
65 	struct futex_st0 st;
66 
67 	st.oparg = oparg;
68 	st.oldval = oldval;
69 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
70 	    futex_xchgl_slow0, &st) != 0)
71 		return (EFAULT);
72 	return (0);
73 }
74 
75 static void
76 futex_addl_slow0(vm_offset_t kva, void *arg)
77 {
78 	struct futex_st0 *st;
79 
80 	st = arg;
81 	*st->oldval = atomic_fetchadd_int((int *)kva, st->oparg);
82 }
83 
84 int
85 futex_addl(int oparg, uint32_t *uaddr, int *oldval)
86 {
87 	struct futex_st0 st;
88 
89 	st.oparg = oparg;
90 	st.oldval = oldval;
91 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
92 	    futex_addl_slow0, &st) != 0)
93 		return (EFAULT);
94 	return (0);
95 }
96 
97 static void
98 futex_orl_slow0(vm_offset_t kva, void *arg)
99 {
100 	struct futex_st0 *st;
101 	int old;
102 
103 	st = arg;
104 	old = *(int *)kva;
105 	while (!atomic_fcmpset_int((int *)kva, &old, old | st->oparg))
106 		;
107 	*st->oldval = old;
108 }
109 
110 int
111 futex_orl(int oparg, uint32_t *uaddr, int *oldval)
112 {
113 	struct futex_st0 st;
114 
115 	st.oparg = oparg;
116 	st.oldval = oldval;
117 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
118 	    futex_orl_slow0, &st) != 0)
119 		return (EFAULT);
120 	return (0);
121 }
122 
123 static void
124 futex_andl_slow0(vm_offset_t kva, void *arg)
125 {
126 	struct futex_st0 *st;
127 	int old;
128 
129 	st = arg;
130 	old = *(int *)kva;
131 	while (!atomic_fcmpset_int((int *)kva, &old, old & st->oparg))
132 		;
133 	*st->oldval = old;
134 }
135 
136 int
137 futex_andl(int oparg, uint32_t *uaddr, int *oldval)
138 {
139 	struct futex_st0 st;
140 
141 	st.oparg = oparg;
142 	st.oldval = oldval;
143 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
144 	    futex_andl_slow0, &st) != 0)
145 		return (EFAULT);
146 	return (0);
147 }
148 
149 static void
150 futex_xorl_slow0(vm_offset_t kva, void *arg)
151 {
152 	struct futex_st0 *st;
153 	int old;
154 
155 	st = arg;
156 	old = *(int *)kva;
157 	while (!atomic_fcmpset_int((int *)kva, &old, old ^ st->oparg))
158 		;
159 	*st->oldval = old;
160 }
161 
162 int
163 futex_xorl(int oparg, uint32_t *uaddr, int *oldval)
164 {
165 	struct futex_st0 st;
166 
167 	st.oparg = oparg;
168 	st.oldval = oldval;
169 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
170 	    futex_xorl_slow0, &st) != 0)
171 		return (EFAULT);
172 	return (0);
173 }
174