1 /*
2 * Mesa 3-D graphics library
3 * Version: 6.5
4 *
5 * Copyright (C) 1999-2005 Brian Paul All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25
26 /**
27 * \file execmem.c
28 * Functions for allocating executable memory.
29 *
30 * \author Keith Whitwell
31 */
32
33
34 #include "imports.h"
35 #include "glapi/glthread.h"
36
37
38
39 #if defined(__linux__) || defined(__OpenBSD__) || defined(_NetBSD__) || defined(__sun)
40
41 /*
42 * Allocate a large block of memory which can hold code then dole it out
43 * in pieces by means of the generic memory manager code.
44 */
45
46 #include <unistd.h>
47 #include <sys/mman.h>
48 #include "mm.h"
49
50 #ifdef MESA_SELINUX
51 #include <selinux/selinux.h>
52 #endif
53
54
55 #ifndef MAP_ANONYMOUS
56 #define MAP_ANONYMOUS MAP_ANON
57 #endif
58
59
60 #define EXEC_HEAP_SIZE (10*1024*1024)
61
62 _glthread_DECLARE_STATIC_MUTEX(exec_mutex);
63
64 static struct mem_block *exec_heap = NULL;
65 static unsigned char *exec_mem = NULL;
66
67
68 static int
init_heap(void)69 init_heap(void)
70 {
71 #ifdef MESA_SELINUX
72 if (is_selinux_enabled()) {
73 if (!security_get_boolean_active("allow_execmem") ||
74 !security_get_boolean_pending("allow_execmem"))
75 return 0;
76 }
77 #endif
78
79 if (!exec_heap)
80 exec_heap = mmInit( 0, EXEC_HEAP_SIZE );
81
82 if (!exec_mem)
83 exec_mem = mmap(NULL, EXEC_HEAP_SIZE, PROT_EXEC | PROT_READ | PROT_WRITE,
84 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
85
86 return (exec_mem != MAP_FAILED);
87 }
88
89
90 void *
_mesa_exec_malloc(GLuint size)91 _mesa_exec_malloc(GLuint size)
92 {
93 struct mem_block *block = NULL;
94 void *addr = NULL;
95
96 _glthread_LOCK_MUTEX(exec_mutex);
97
98 if (!init_heap())
99 goto bail;
100
101 if (exec_heap) {
102 size = (size + 31) & ~31;
103 block = mmAllocMem( exec_heap, size, 32, 0 );
104 }
105
106 if (block)
107 addr = exec_mem + block->ofs;
108 else
109 printf("_mesa_exec_malloc failed\n");
110
111 bail:
112 _glthread_UNLOCK_MUTEX(exec_mutex);
113
114 return addr;
115 }
116
117
118 void
_mesa_exec_free(void * addr)119 _mesa_exec_free(void *addr)
120 {
121 _glthread_LOCK_MUTEX(exec_mutex);
122
123 if (exec_heap) {
124 struct mem_block *block = mmFindBlock(exec_heap, (unsigned char *)addr - exec_mem);
125
126 if (block)
127 mmFreeMem(block);
128 }
129
130 _glthread_UNLOCK_MUTEX(exec_mutex);
131 }
132
133
134 #else
135
136 /*
137 * Just use regular memory.
138 */
139
140 void *
_mesa_exec_malloc(GLuint size)141 _mesa_exec_malloc(GLuint size)
142 {
143 return malloc( size );
144 }
145
146
147 void
_mesa_exec_free(void * addr)148 _mesa_exec_free(void *addr)
149 {
150 free(addr);
151 }
152
153
154 #endif
155