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 HAVE_FUNC_ATTRIBUTE_VISIBILITY
29 #define HIDDEN __attribute__((visibility("hidden")))
30 #else
31 #define HIDDEN
32 #endif
33
34 __asm__(".text\n"
35 ".balign 32\n"
36 "x86_64_entry_start:");
37
38 #define STUB_ASM_ENTRY(func) \
39 ".globl " func "\n" \
40 ".type " func ", @function\n" \
41 ".balign 32\n" \
42 func ":"
43
44 #ifndef __ILP32__
45
46 #define STUB_ASM_CODE(slot) \
47 "movq " ENTRY_CURRENT_TABLE "@GOTTPOFF(%rip), %rax\n\t" \
48 "movq %fs:(%rax), %r11\n\t" \
49 "jmp *(8 * " slot ")(%r11)"
50
51 #else
52
53 #define STUB_ASM_CODE(slot) \
54 "movq " ENTRY_CURRENT_TABLE "@GOTTPOFF(%rip), %rax\n\t" \
55 "movl %fs:(%rax), %r11d\n\t" \
56 "movl 4*" slot "(%r11d), %r11d\n\t" \
57 "jmp *%r11"
58
59 #endif
60
61 #define MAPI_TMP_STUB_ASM_GCC
62 #include "mapi_tmp.h"
63
64 #ifndef MAPI_MODE_BRIDGE
65
66 #include <string.h>
67 #include "u_execmem.h"
68
69 void
entry_patch_public(void)70 entry_patch_public(void)
71 {
72 }
73
74 extern char
75 x86_64_entry_start[] HIDDEN;
76
77 mapi_func
entry_get_public(int slot)78 entry_get_public(int slot)
79 {
80 return (mapi_func) (x86_64_entry_start + slot * 32);
81 }
82
83 void
entry_patch(mapi_func entry,int slot)84 entry_patch(mapi_func entry, int slot)
85 {
86 char *code = (char *) entry;
87 int offset = 12;
88 #ifdef __ILP32__
89 offset = 13;
90 #endif
91 *((unsigned int *) (code + offset)) = slot * sizeof(mapi_func);
92 }
93
94 mapi_func
entry_generate(int slot)95 entry_generate(int slot)
96 {
97 const char code_templ[] = {
98 #ifndef __ILP32__
99 /* movq %fs:0, %r11 */
100 0x64, 0x4c, 0x8b, 0x1c, 0x25, 0x00, 0x00, 0x00, 0x00,
101 /* jmp *0x1234(%r11) */
102 0x41, 0xff, 0xa3, 0x34, 0x12, 0x00, 0x00,
103 #else
104 /* movl %fs:0, %r11d */
105 0x64, 0x44, 0x8b, 0x1c, 0x25, 0x00, 0x00, 0x00, 0x00,
106 /* movl 0x1234(%r11d), %r11d */
107 0x67, 0x45, 0x8b, 0x9b, 0x34, 0x12, 0x00, 0x00,
108 /* jmp *%r11 */
109 0x41, 0xff, 0xe3,
110 #endif
111 };
112 unsigned long long addr;
113 char *code;
114 mapi_func entry;
115
116 __asm__("movq " ENTRY_CURRENT_TABLE "@GOTTPOFF(%%rip), %0"
117 : "=r" (addr));
118 if ((addr >> 32) != 0xffffffff)
119 return NULL;
120 addr &= 0xffffffff;
121
122 code = u_execmem_alloc(sizeof(code_templ));
123 if (!code)
124 return NULL;
125
126 memcpy(code, code_templ, sizeof(code_templ));
127
128 *((unsigned int *) (code + 5)) = addr;
129 entry = (mapi_func) code;
130 entry_patch(entry, slot);
131
132 return entry;
133 }
134
135 #endif /* MAPI_MODE_BRIDGE */
136