xref: /freebsd/sys/i386/linux/linux_copyout.c (revision 6be3386466ab79a84b48429ae66244f21526d3df)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2018 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
8  * under sponsorship from the FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_compat.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/imgact.h>
40 #include <sys/lock.h>
41 #include <sys/sx.h>
42 #include <vm/vm.h>
43 #include <vm/vm_param.h>
44 #include <vm/vm_extern.h>
45 #include <vm/pmap.h>
46 
47 #include <machine/atomic.h>
48 #include <machine/md_var.h>
49 
50 #include <compat/linux/linux_emul.h>
51 #include <compat/linux/linux_futex.h>
52 
53 struct futex_st0 {
54 	int oparg;
55 	int *oldval;
56 };
57 
58 static void
59 futex_xchgl_slow0(vm_offset_t kva, void *arg)
60 {
61 	struct futex_st0 *st;
62 
63 	st = arg;
64 	*st->oldval = atomic_swap_int((int *)kva, st->oparg);
65 }
66 
67 int
68 futex_xchgl(int oparg, uint32_t *uaddr, int *oldval)
69 {
70 	struct futex_st0 st;
71 
72 	st.oparg = oparg;
73 	st.oldval = oldval;
74 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
75 	    futex_xchgl_slow0, &st) != 0)
76 		return (-EFAULT);
77 	return (0);
78 }
79 
80 static void
81 futex_addl_slow0(vm_offset_t kva, void *arg)
82 {
83 	struct futex_st0 *st;
84 
85 	st = arg;
86 	*st->oldval = atomic_fetchadd_int((int *)kva, st->oparg);
87 }
88 
89 int
90 futex_addl(int oparg, uint32_t *uaddr, int *oldval)
91 {
92 	struct futex_st0 st;
93 
94 	st.oparg = oparg;
95 	st.oldval = oldval;
96 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
97 	    futex_addl_slow0, &st) != 0)
98 		return (-EFAULT);
99 	return (0);
100 }
101 
102 static void
103 futex_orl_slow0(vm_offset_t kva, void *arg)
104 {
105 	struct futex_st0 *st;
106 	int old;
107 
108 	st = arg;
109 	old = *(int *)kva;
110 	while (!atomic_fcmpset_int((int *)kva, &old, old | st->oparg))
111 		;
112 	*st->oldval = old;
113 }
114 
115 int
116 futex_orl(int oparg, uint32_t *uaddr, int *oldval)
117 {
118 	struct futex_st0 st;
119 
120 	st.oparg = oparg;
121 	st.oldval = oldval;
122 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
123 	    futex_orl_slow0, &st) != 0)
124 		return (-EFAULT);
125 	return (0);
126 }
127 
128 static void
129 futex_andl_slow0(vm_offset_t kva, void *arg)
130 {
131 	struct futex_st0 *st;
132 	int old;
133 
134 	st = arg;
135 	old = *(int *)kva;
136 	while (!atomic_fcmpset_int((int *)kva, &old, old & st->oparg))
137 		;
138 	*st->oldval = old;
139 }
140 
141 int
142 futex_andl(int oparg, uint32_t *uaddr, int *oldval)
143 {
144 	struct futex_st0 st;
145 
146 	st.oparg = oparg;
147 	st.oldval = oldval;
148 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
149 	    futex_andl_slow0, &st) != 0)
150 		return (-EFAULT);
151 	return (0);
152 }
153 
154 static void
155 futex_xorl_slow0(vm_offset_t kva, void *arg)
156 {
157 	struct futex_st0 *st;
158 	int old;
159 
160 	st = arg;
161 	old = *(int *)kva;
162 	while (!atomic_fcmpset_int((int *)kva, &old, old ^ st->oparg))
163 		;
164 	*st->oldval = old;
165 }
166 
167 int
168 futex_xorl(int oparg, uint32_t *uaddr, int *oldval)
169 {
170 	struct futex_st0 st;
171 
172 	st.oparg = oparg;
173 	st.oldval = oldval;
174 	if (cp_slow0((vm_offset_t)uaddr, sizeof(uint32_t), true,
175 	    futex_xorl_slow0, &st) != 0)
176 		return (-EFAULT);
177 	return (0);
178 }
179