1/**************************************************************************
2 *
3 * Copyright (C) 1999-2005  Brian Paul   All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included
13 * in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
19 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
20 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21 *
22 **************************************************************************/
23
24
25/**
26 * \file exemem.c
27 * Functions for allocating executable memory.
28 *
29 * \author Keith Whitwell
30 */
31
32
33#include "pipe/p_compiler.h"
34#include "util/u_debug.h"
35#include "os/os_thread.h"
36#include "util/u_memory.h"
37
38#include "rtasm_execmem.h"
39
40#if defined(PIPE_OS_BSD)
41#define MAP_ANONYMOUS MAP_ANON
42#endif
43
44#if defined(PIPE_OS_WINDOWS)
45#ifndef WIN32_LEAN_AND_MEAN
46#define WIN32_LEAN_AND_MEAN 1
47#endif
48#include <windows.h>
49#endif
50
51#if defined(PIPE_OS_LINUX) || defined(PIPE_OS_BSD) || defined(PIPE_OS_SOLARIS)
52
53
54/*
55 * Allocate a large block of memory which can hold code then dole it out
56 * in pieces by means of the generic memory manager code.
57 */
58
59#include <unistd.h>
60#include <sys/mman.h>
61#include "util/u_mm.h"
62
63#define EXEC_HEAP_SIZE (10*1024*1024)
64
65pipe_static_mutex(exec_mutex);
66
67static struct mem_block *exec_heap = NULL;
68static unsigned char *exec_mem = NULL;
69
70
71static void
72init_heap(void)
73{
74   if (!exec_heap)
75      exec_heap = u_mmInit( 0, EXEC_HEAP_SIZE );
76
77   if (!exec_mem)
78      exec_mem = (unsigned char *) mmap(0, EXEC_HEAP_SIZE,
79					PROT_EXEC | PROT_READ | PROT_WRITE,
80					MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
81}
82
83
84void *
85rtasm_exec_malloc(size_t size)
86{
87   struct mem_block *block = NULL;
88   void *addr = NULL;
89
90   pipe_mutex_lock(exec_mutex);
91
92   init_heap();
93
94   if (exec_heap) {
95      size = (size + 31) & ~31;  /* next multiple of 32 bytes */
96      block = u_mmAllocMem( exec_heap, size, 5, 0 ); /* 5 -> 32-byte alignment */
97   }
98
99   if (block)
100      addr = exec_mem + block->ofs;
101   else
102      debug_printf("rtasm_exec_malloc failed\n");
103
104   pipe_mutex_unlock(exec_mutex);
105
106   return addr;
107}
108
109
110void
111rtasm_exec_free(void *addr)
112{
113   pipe_mutex_lock(exec_mutex);
114
115   if (exec_heap) {
116      struct mem_block *block = u_mmFindBlock(exec_heap, (unsigned char *)addr - exec_mem);
117
118      if (block)
119	 u_mmFreeMem(block);
120   }
121
122   pipe_mutex_unlock(exec_mutex);
123}
124
125
126#elif defined(PIPE_OS_WINDOWS)
127
128
129/*
130 * Avoid Data Execution Prevention.
131 */
132
133void *
134rtasm_exec_malloc(size_t size)
135{
136   return VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
137}
138
139
140void
141rtasm_exec_free(void *addr)
142{
143   VirtualFree(addr, 0, MEM_RELEASE);
144}
145
146
147#else
148
149
150/*
151 * Just use regular memory.
152 */
153
154void *
155rtasm_exec_malloc(size_t size)
156{
157   return MALLOC( size );
158}
159
160
161void
162rtasm_exec_free(void *addr)
163{
164   FREE(addr);
165}
166
167
168#endif
169