1/*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2005  Brian Paul   All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * 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 <stdio.h>
35#include "main/glheader.h"
36#include "execmem.h"
37#include "c11/threads.h"
38
39
40#if defined(__linux__) || defined(__OpenBSD__) || defined(__NetBSD__) || defined(__sun) || defined(__HAIKU__)
41
42/*
43 * Allocate a large block of memory which can hold code then dole it out
44 * in pieces by means of the generic memory manager code.
45*/
46
47#include <unistd.h>
48#include <sys/mman.h>
49#include "util/u_mm.h"
50
51#ifdef MESA_SELINUX
52#include <selinux/selinux.h>
53#endif
54
55
56#ifndef MAP_ANONYMOUS
57#define MAP_ANONYMOUS MAP_ANON
58#endif
59
60
61#define EXEC_HEAP_SIZE (10*1024*1024)
62
63static mtx_t exec_mutex = _MTX_INITIALIZER_NP;
64
65static struct mem_block *exec_heap = NULL;
66static unsigned char *exec_mem = NULL;
67
68
69static int
70init_heap(void)
71{
72#ifdef MESA_SELINUX
73   if (is_selinux_enabled()) {
74      if (!security_get_boolean_active("allow_execmem") ||
75	  !security_get_boolean_pending("allow_execmem"))
76         return 0;
77   }
78#endif
79
80   if (!exec_heap)
81      exec_heap = u_mmInit( 0, EXEC_HEAP_SIZE );
82
83   if (!exec_mem)
84      exec_mem = mmap(NULL, EXEC_HEAP_SIZE, PROT_EXEC | PROT_READ | PROT_WRITE,
85                      MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
86
87   return (exec_mem != MAP_FAILED);
88}
89
90
91void *
92_mesa_exec_malloc(unsigned size)
93{
94   struct mem_block *block = NULL;
95   void *addr = NULL;
96
97   mtx_lock(&exec_mutex);
98
99   if (!init_heap())
100      goto bail;
101
102   if (exec_heap) {
103      size = (size + 31) & ~31;
104      block = u_mmAllocMem(exec_heap, size, 5, 0);
105   }
106
107   if (block)
108      addr = exec_mem + block->ofs;
109   else
110      printf("_mesa_exec_malloc failed\n");
111
112bail:
113   mtx_unlock(&exec_mutex);
114
115   return addr;
116}
117
118
119void
120_mesa_exec_free(void *addr)
121{
122   mtx_lock(&exec_mutex);
123
124   if (exec_heap) {
125      struct mem_block *block = u_mmFindBlock(exec_heap, (unsigned char *)addr - exec_mem);
126
127      if (block)
128	 u_mmFreeMem(block);
129   }
130
131   mtx_unlock(&exec_mutex);
132}
133
134
135#else
136
137/*
138 * Just use regular memory.
139 */
140
141void *
142_mesa_exec_malloc(unsigned size)
143{
144   return malloc( size );
145}
146
147
148void
149_mesa_exec_free(void *addr)
150{
151   free(addr);
152}
153
154
155#endif
156