15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Mesa 3-D graphics library 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Version: 6.5 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Copyright (C) 1999-2005 Brian Paul All Rights Reserved. 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Permission is hereby granted, free of charge, to any person obtaining a 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * copy of this software and associated documentation files (the "Software"), 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * to deal in the Software without restriction, including without limitation 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * the rights to use, copy, modify, merge, publish, distribute, sublicense, 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * and/or sell copies of the Software, and to permit persons to whom the 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Software is furnished to do so, subject to the following conditions: 135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * 145e3f23d412006dc4db4e659864679f29341e113fTorne (Richard Coles) * The above copyright notice and this permission notice shall be included 15c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) * in all copies or substantial portions of the Software. 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/** 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * \file glapi_execmem.c 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Function for allocating executable memory for dispatch stubs. 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * 315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Copied from main/execmem.c and simplified for dispatch stubs. 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "u_compiler.h" 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "u_thread.h" 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "u_execmem.h" 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#define EXEC_MAP_SIZE (4*1024) 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)u_mutex_declare_static(exec_mutex); 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static unsigned int head = 0; 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static unsigned char *exec_mem = (unsigned char *)0; 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#if defined(__linux__) || defined(__OpenBSD__) || defined(_NetBSD__) || defined(__sun) 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <unistd.h> 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <sys/mman.h> 535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifdef MESA_SELINUX 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <selinux/selinux.h> 565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifndef MAP_ANONYMOUS 605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#define MAP_ANONYMOUS MAP_ANON 615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Dispatch stubs are of fixed size and never freed. Thus, we do not need to 665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * overlay a heap, we just mmap a page and manage through an index. 675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static int 705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)init_map(void) 715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles){ 725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifdef MESA_SELINUX 735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (is_selinux_enabled()) { 745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!security_get_boolean_active("allow_execmem") || 755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) !security_get_boolean_pending("allow_execmem")) 765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return 0; 775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif 795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!exec_mem) 815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exec_mem = mmap(NULL, EXEC_MAP_SIZE, PROT_EXEC | PROT_READ | PROT_WRITE, 825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return (exec_mem != MAP_FAILED); 855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#elif defined(_WIN32) 895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <windows.h> 915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Avoid Data Execution Prevention. 955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 97static int 98init_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 <stdlib.h> 109 110static int 111init_map(void) 112{ 113 exec_mem = malloc(EXEC_MAP_SIZE); 114 115 return (exec_mem != NULL); 116} 117 118 119#endif 120 121void * 122u_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 139bail: 140 u_mutex_unlock(exec_mutex); 141 142 return addr; 143} 144 145 146