workbench/libs/mesa/src/gallium/auxiliary/rtasm/rtasm_execmem.c

   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
  65 pipe_static_mutex(exec_mutex);
  66
  67 static struct mem_block *exec_heap = NULL;
  68 static unsigned char *exec_mem = NULL;
  69
  70
  71 static void
  72 init_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
  84 void *
  85 rtasm_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
 110 void
 111 rtasm_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
 133 void *
 134 rtasm_exec_malloc(size_t size)
 135 {
 136    return VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
 137 }
 138
 139
 140 void
 141 rtasm_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
 154 void *
 155 rtasm_exec_malloc(size_t size)
 156 {
 157    return MALLOC( size );
 158 }
 159
 160
 161 void
 162 rtasm_exec_free(void *addr)
 163 {
 164    FREE(addr);
 165 }
 166
 167
 168 #endif