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  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  21  * OTHER DEALINGS IN THE SOFTWARE.
  22  *
  23  **************************************************************************/
  24
  25
  26 /**
  27  * \file exemem.c
  28  * Functions for allocating executable memory.
  29  *
  30  * \author Keith Whitwell
  31  */
  32
  33
  34 #include "pipe/p_compiler.h"
  35 #include "util/u_debug.h"
  36 #include "os/os_thread.h"
  37 #include "util/u_memory.h"
  38
  39 #include "rtasm_execmem.h"
  40
  41 #ifndef MAP_ANONYMOUS
  42 #define MAP_ANONYMOUS MAP_ANON
  43 #endif
  44
  45 #if defined(PIPE_OS_WINDOWS)
  46 #ifndef WIN32_LEAN_AND_MEAN
  47 #define WIN32_LEAN_AND_MEAN 1
  48 #endif
  49 #include <windows.h>
  50 #endif
  51
  52 #if defined(PIPE_OS_UNIX)
  53
  54
  55 /*
  56  * Allocate a large block of memory which can hold code then dole it out
  57  * in pieces by means of the generic memory manager code.
  58  */
  59
  60 #include <unistd.h>
  61 #include <sys/mman.h>
  62 #include "util/u_mm.h"
  63
  64 #define EXEC_HEAP_SIZE (10*1024*1024)
  65
  66 pipe_static_mutex(exec_mutex);
  67
  68 static struct mem_block *exec_heap = NULL;
  69 static unsigned char *exec_mem = NULL;
  70
  71
  72 static int
  73 init_heap(void)
  74 {
  75    if (!exec_heap)
  76       exec_heap = u_mmInit( 0, EXEC_HEAP_SIZE );
  77
  78    if (!exec_mem)
  79       exec_mem = (unsigned char *) mmap(0, EXEC_HEAP_SIZE,
  80                                         PROT_EXEC | PROT_READ | PROT_WRITE,
  81                                         MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  82
  83    return (exec_mem != MAP_FAILED);
  84 }
  85
  86
  87 void *
  88 rtasm_exec_malloc(size_t size)
  89 {
  90    struct mem_block *block = NULL;
  91    void *addr = NULL;
  92
  93    pipe_mutex_lock(exec_mutex);
  94
  95    if (!init_heap())
  96       goto bail;
  97
  98    if (exec_heap) {
  99       size = (size + 31) & ~31;  /* next multiple of 32 bytes */
 100       block = u_mmAllocMem( exec_heap, size, 5, 0 ); /* 5 -> 32-byte alignment */
 101    }
 102
 103    if (block)
 104       addr = exec_mem + block->ofs;
 105    else
 106       debug_printf("rtasm_exec_malloc failed\n");
 107
 108 bail:
 109    pipe_mutex_unlock(exec_mutex);
 110
 111    return addr;
 112 }
 113
 114
 115 void
 116 rtasm_exec_free(void *addr)
 117 {
 118    pipe_mutex_lock(exec_mutex);
 119
 120    if (exec_heap) {
 121       struct mem_block *block = u_mmFindBlock(exec_heap, (unsigned char *)addr - exec_mem);
 122
 123       if (block)
 124          u_mmFreeMem(block);
 125    }
 126
 127    pipe_mutex_unlock(exec_mutex);
 128 }
 129
 130
 131 #elif defined(PIPE_OS_WINDOWS)
 132
 133
 134 /*
 135  * Avoid Data Execution Prevention.
 136  */
 137
 138 void *
 139 rtasm_exec_malloc(size_t size)
 140 {
 141    return VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
 142 }
 143
 144
 145 void
 146 rtasm_exec_free(void *addr)
 147 {
 148    VirtualFree(addr, 0, MEM_RELEASE);
 149 }
 150
 151
 152 #else
 153
 154
 155 /*
 156  * Just use regular memory.
 157  */
 158
 159 void *
 160 rtasm_exec_malloc(size_t size)
 161 {
 162    return MALLOC( size );
 163 }
 164
 165
 166 void
 167 rtasm_exec_free(void *addr)
 168 {
 169    FREE(addr);
 170 }
 171
 172
 173 #endif