src/mapi/entry_x86_tsd.h

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 2010 LunarG Inc.
   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 OR
  17  * 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 OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  *
  24  * Authors:
  25  *    Chia-I Wu <olv@lunarg.com>
  26  */
  27
  28 #ifdef __CET__
  29 #define ENDBR "endbr32\n\t"
  30 #else
  31 #define ENDBR
  32 #endif
  33
  34 #ifdef HAVE_FUNC_ATTRIBUTE_VISIBILITY
  35 #define HIDDEN __attribute__((visibility("hidden")))
  36 #else
  37 #define HIDDEN
  38 #endif
  39
  40 #define X86_ENTRY_SIZE 64
  41
  42 __asm__(".text\n"
  43         ".balign 32\n"
  44         "x86_entry_start:");
  45
  46 #define STUB_ASM_ENTRY(func)        \
  47    ".globl " func "\n"              \
  48    ".type " func ", @function\n"    \
  49    ".balign 32\n"                   \
  50    func ":"
  51
  52 #define STUB_ASM_CODE(slot)         \
  53    ENDBR                            \
  54    "call 1f\n\t"                    \
  55    "1:\n\t"                         \
  56    "popl %ecx\n\t"                  \
  57    "addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ecx\n\t" \
  58    "movl " ENTRY_CURRENT_TABLE "@GOT(%ecx), %eax\n\t" \
  59    "mov (%eax), %eax\n\t"           \
  60    "testl %eax, %eax\n\t"           \
  61    "jne 1f\n\t"                     \
  62    "push %ebx\n\t"                  \
  63    "movl %ecx, %ebx\n\t"            \
  64    "call " ENTRY_CURRENT_TABLE_GET "@PLT\n\t" \
  65    "popl %ebx\n\t"                  \
  66    "1:\n\t"                         \
  67    "jmp *(4 * " slot ")(%eax)"
  68
  69 #define MAPI_TMP_STUB_ASM_GCC
  70 #include "mapi_tmp.h"
  71
  72 #ifndef MAPI_MODE_BRIDGE
  73
  74 __asm__(".balign 32\n"
  75         "x86_entry_end:");
  76
  77 #include <string.h>
  78 #include "u_execmem.h"
  79
  80 extern const char x86_entry_start[] HIDDEN;
  81 extern const char x86_entry_end[] HIDDEN;
  82
  83 void
  84 entry_patch_public(void)
  85 {
  86 }
  87
  88 mapi_func
  89 entry_get_public(int slot)
  90 {
  91    return (mapi_func) (x86_entry_start + slot * X86_ENTRY_SIZE);
  92 }
  93
  94 void
  95 entry_patch(mapi_func entry, int slot)
  96 {
  97    char *code = (char *) entry;
  98
  99    *((unsigned long *) (code + 11)) = slot * sizeof(mapi_func);
 100    *((unsigned long *) (code + 22)) = slot * sizeof(mapi_func);
 101 }
 102
 103 mapi_func
 104 entry_generate(int slot)
 105 {
 106    const char *code_templ = x86_entry_end - X86_ENTRY_SIZE;
 107    void *code;
 108    mapi_func entry;
 109
 110    code = u_execmem_alloc(X86_ENTRY_SIZE);
 111    if (!code)
 112       return NULL;
 113
 114    memcpy(code, code_templ, X86_ENTRY_SIZE);
 115    entry = (mapi_func) code;
 116    entry_patch(entry, slot);
 117
 118    return entry;
 119 }
 120
 121 #endif /* MAPI_MODE_BRIDGE */