Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 4358 | Serge | 1 | /* |
| 2 | * Mesa 3-D graphics library |
||
| 3 | * |
||
| 4 | * Copyright (C) 1999-2005 Brian Paul All Rights Reserved. |
||
| 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 |
||
| 17 | * OR 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 |
||
| 20 | * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
||
| 21 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
||
| 22 | * OTHER DEALINGS IN THE SOFTWARE. |
||
| 23 | */ |
||
| 24 | |||
| 25 | |||
| 26 | /** |
||
| 27 | * \file glapi_execmem.c |
||
| 28 | * |
||
| 29 | * Function for allocating executable memory for dispatch stubs. |
||
| 30 | * |
||
| 31 | * Copied from main/execmem.c and simplified for dispatch stubs. |
||
| 32 | */ |
||
| 33 | |||
| 34 | |||
| 35 | #include "u_compiler.h" |
||
| 36 | #include "u_thread.h" |
||
| 37 | #include "u_execmem.h" |
||
| 38 | |||
| 39 | |||
| 40 | #define EXEC_MAP_SIZE (4*1024) |
||
| 41 | |||
| 42 | u_mutex_declare_static(exec_mutex); |
||
| 43 | |||
| 44 | static unsigned int head = 0; |
||
| 45 | |||
| 46 | static unsigned char *exec_mem = (unsigned char *)0; |
||
| 47 | |||
| 48 | |||
| 49 | #if defined(__linux__) || defined(__OpenBSD__) || defined(_NetBSD__) || defined(__sun) || defined(__HAIKU__) |
||
| 50 | |||
| 51 | #include |
||
| 52 | #include |
||
| 53 | |||
| 54 | #ifdef MESA_SELINUX |
||
| 55 | #include |
||
| 56 | #endif |
||
| 57 | |||
| 58 | |||
| 59 | #ifndef MAP_ANONYMOUS |
||
| 60 | #define MAP_ANONYMOUS MAP_ANON |
||
| 61 | #endif |
||
| 62 | |||
| 63 | |||
| 64 | /* |
||
| 65 | * Dispatch stubs are of fixed size and never freed. Thus, we do not need to |
||
| 66 | * overlay a heap, we just mmap a page and manage through an index. |
||
| 67 | */ |
||
| 68 | |||
| 69 | static int |
||
| 70 | init_map(void) |
||
| 71 | { |
||
| 72 | #ifdef MESA_SELINUX |
||
| 73 | if (is_selinux_enabled()) { |
||
| 74 | if (!security_get_boolean_active("allow_execmem") || |
||
| 75 | !security_get_boolean_pending("allow_execmem")) |
||
| 76 | return 0; |
||
| 77 | } |
||
| 78 | #endif |
||
| 79 | |||
| 80 | if (!exec_mem) |
||
| 81 | exec_mem = mmap(NULL, EXEC_MAP_SIZE, PROT_EXEC | PROT_READ | PROT_WRITE, |
||
| 82 | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
||
| 83 | |||
| 84 | return (exec_mem != MAP_FAILED); |
||
| 85 | } |
||
| 86 | |||
| 87 | |||
| 88 | #elif defined(_WIN32) |
||
| 89 | |||
| 90 | #include |
||
| 91 | |||
| 92 | |||
| 93 | /* |
||
| 94 | * Avoid Data Execution Prevention. |
||
| 95 | */ |
||
| 96 | |||
| 97 | static int |
||
| 98 | init_map(void) |
||
| 99 | { |
||
| 100 | exec_mem = VirtualAlloc(NULL, EXEC_MAP_SIZE, MEM_COMMIT, PAGE_EXECUTE_READWRITE); |
||
| 101 | |||
| 102 | return (exec_mem != NULL); |
||
| 103 | } |
||
| 104 | |||
| 105 | |||
| 106 | #else |
||
| 107 | |||
| 108 | #include |
||
| 109 | |||
| 110 | static int |
||
| 111 | init_map(void) |
||
| 112 | { |
||
| 113 | exec_mem = malloc(EXEC_MAP_SIZE); |
||
| 114 | |||
| 115 | return (exec_mem != NULL); |
||
| 116 | } |
||
| 117 | |||
| 118 | |||
| 119 | #endif |
||
| 120 | |||
| 121 | void * |
||
| 122 | u_execmem_alloc(unsigned int size) |
||
| 123 | { |
||
| 124 | void *addr = NULL; |
||
| 125 | |||
| 126 | u_mutex_lock(exec_mutex); |
||
| 127 | |||
| 128 | if (!init_map()) |
||
| 129 | goto bail; |
||
| 130 | |||
| 131 | /* free space check, assumes no integer overflow */ |
||
| 132 | if (head + size > EXEC_MAP_SIZE) |
||
| 133 | goto bail; |
||
| 134 | |||
| 135 | /* allocation, assumes proper addr and size alignement */ |
||
| 136 | addr = exec_mem + head; |
||
| 137 | head += size; |
||
| 138 | |||
| 139 | bail: |
||
| 140 | u_mutex_unlock(exec_mutex); |
||
| 141 | |||
| 142 | return addr; |
||
| 143 | } |
||
| 144 |