/* Title: paging.h */ /* * DUMA - Red-Zone memory allocator. * Copyright (C) 2006 Michael Eddington * Copyright (C) 2002-2008 Hayati Ayguen , Procitec GmbH * Copyright (C) 1987-1999 Bruce Perens * License: GNU GPL (GNU General Public License, see COPYING-GPL) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * * FILE CONTENTS: * internal implementation file * contains system/platform dependent paging functions */ #ifndef DUMA_PAGING_H #define DUMA_PAGING_H /* * Lots of systems are missing the definition of PROT_NONE. */ #ifndef PROT_NONE #define PROT_NONE 0 #endif /* * 386 BSD has MAP_ANON instead of MAP_ANONYMOUS. */ #if ( !defined(MAP_ANONYMOUS) && defined(MAP_ANON) ) #define MAP_ANONYMOUS MAP_ANON #endif /* * For some reason, I can't find mprotect() in any of the headers on * IRIX or SunOS 4.1.2 */ /* extern C_LINKAGE int mprotect(void * addr, size_t len, int prot); */ #if !defined(WIN32) static caddr_t startAddr = (caddr_t) 0; #endif /* Function: stringErrorReport * * Get formatted error string and return. For WIN32 * FormatMessage is used, strerror all else. */ static const char * stringErrorReport(void) { #if defined(WIN32) DWORD LastError; LPVOID lpMsgBuf; LastError = GetLastError(); FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS , NULL , LastError , MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT) /* Default language */ , (LPTSTR) &lpMsgBuf , 0 , NULL ); return (char*)lpMsgBuf; /* "Unknown error.\n"; */ #elif defined(DUMA_NO_STRERROR) return DUMA_strerror(errno); #else return strerror(errno); #endif } /* Function: mprotectFailed * * Report that VirtualProtect or mprotect failed and abort * program execution. */ static void mprotectFailed(void) { #if defined(WIN32) DUMA_Abort("VirtualProtect() failed: %s", stringErrorReport()); #else DUMA_Abort("mprotect() failed: %s.\nCheck README section 'MEMORY USAGE AND EXECUTION SPEED'\n if your (Linux) system may limit the number of different page mappings per process", stringErrorReport()); #endif } /* Function: Page_Create * * Create memory. Allocates actual memory. Uses * VirtualAlloc on windows and mmap on unix. * * See Also: * */ static void * Page_Create(size_t size, int exitonfail, int printerror) { caddr_t allocation; #if defined(WIN32) allocation = VirtualAlloc( NULL /* address of region to reserve or commit */ , (DWORD) size /* size of region */ , (DWORD) MEM_COMMIT /* type of allocation */ , (DWORD) PAGE_READWRITE /* type of access protection */ ); if ( (caddr_t)0 == allocation ) { if ( exitonfail ) DUMA_Abort("VirtualAlloc(%d) failed: %s", (DUMA_SIZE)size, stringErrorReport()); else if ( printerror ) DUMA_Print("\nDUMA warning: VirtualAlloc(%d) failed: %s", (DUMA_SIZE)size, stringErrorReport()); } #elif defined(MAP_ANONYMOUS) /* * In this version, "startAddr" is a _hint_, not a demand. * When the memory I map here is contiguous with other * mappings, the allocator can coalesce the memory from two * or more mappings into one large contiguous chunk, and thus * might be able to find a fit that would not otherwise have * been possible. I could _force_ it to be contiguous by using * the MMAP_FIXED flag, but I don't want to stomp on memory mappings * generated by other software, etc. */ allocation = (caddr_t) mmap( startAddr , (int)size , PROT_READ|PROT_WRITE , MAP_PRIVATE|MAP_ANONYMOUS , -1 , 0 ); #ifndef __hpux /* * Set the "address hint" for the next mmap() so that it will abut * the mapping we just created. * * HP/UX 9.01 has a kernel bug that makes mmap() fail sometimes * when given a non-zero address hint, so we'll leave the hint set * to zero on that system. HP recently told me this is now fixed. * Someone please tell me when it is probable to assume that most * of those systems that were running 9.01 have been upgraded. */ startAddr = allocation + size; #endif if ( allocation == (caddr_t)-1 ) { allocation = (caddr_t)0; if ( exitonfail ) DUMA_Abort("mmap(%d) failed: %s", (DUMA_SIZE)size, stringErrorReport()); else if ( printerror ) DUMA_Print("\nDUMA warning: mmap(%d) failed: %s", (DUMA_SIZE)size, stringErrorReport()); } #else static int devZeroFd = -1; if ( devZeroFd == -1 ) { devZeroFd = open("/dev/zero", O_RDWR); if ( devZeroFd < 0 ) DUMA_Abort( "open() on /dev/zero failed: %s", stringErrorReport() ); } /* * In this version, "startAddr" is a _hint_, not a demand. * When the memory I map here is contiguous with other * mappings, the allocator can coalesce the memory from two * or more mappings into one large contiguous chunk, and thus * might be able to find a fit that would not otherwise have * been possible. I could _force_ it to be contiguous by using * the MMAP_FIXED flag, but I don't want to stomp on memory mappings * generated by other software, etc. */ allocation = (caddr_t) mmap( startAddr , (int)size , PROT_READ|PROT_WRITE , MAP_PRIVATE , devZeroFd , 0 ); startAddr = allocation + size; if ( allocation == (caddr_t)-1 ) { allocation = (caddr_t)0; if ( exitonfail ) DUMA_Abort("mmap(%d) failed: %s", (DUMA_SIZE)size, stringErrorReport()); else if ( printerror ) DUMA_Print("\nDUMA warning: mmap(%d) failed: %s", (DUMA_SIZE)size, stringErrorReport()); } #endif // TESTING // memset((void*)allocation, 0, startAddr); return (void *)allocation; } /* Function: Page_AllowAccess * * Allow memory access to allocated memory. * * See Also: * */ void Page_AllowAccess(void * address, size_t size) { #if defined(WIN32) SIZE_T OldProtect, retQuery; MEMORY_BASIC_INFORMATION MemInfo; size_t tail_size; BOOL ret; while (size >0) { retQuery = VirtualQuery(address, &MemInfo, sizeof(MemInfo)); if (retQuery < sizeof(MemInfo)) DUMA_Abort("VirtualQuery() failed\n"); tail_size = (size > MemInfo.RegionSize) ? MemInfo.RegionSize : size; ret = VirtualProtect( (LPVOID) address /* address of region of committed pages */ , (DWORD) tail_size /* size of the region */ , (DWORD) PAGE_READWRITE /* desired access protection */ , (PDWORD) &OldProtect /* address of variable to get old protection */ ); if (0 == ret) mprotectFailed(); address = ((char *)address) + tail_size; size -= tail_size; } #else if ( mprotect((caddr_t)address, size, PROT_READ|PROT_WRITE) < 0 ) mprotectFailed(); #endif } /* Function: Page_DenyAccess * * Deny access to allocated memory region. * * See Also: * */ static void Page_DenyAccess(void * address, size_t size) { #if defined(WIN32) SIZE_T OldProtect, retQuery; MEMORY_BASIC_INFORMATION MemInfo; size_t tail_size; BOOL ret; while (size >0) { retQuery = VirtualQuery(address, &MemInfo, sizeof(MemInfo)); if (retQuery < sizeof(MemInfo)) DUMA_Abort("VirtualQuery() failed\n"); tail_size = (size > MemInfo.RegionSize) ? MemInfo.RegionSize : size; ret = VirtualProtect( (LPVOID) address /* address of region of committed pages */ , (DWORD) tail_size /* size of the region */ , (DWORD) PAGE_NOACCESS /* desired access protection */ , (PDWORD) &OldProtect /* address of variable to get old protection */ ); if (0 == ret) mprotectFailed(); address = ((char *)address) + tail_size; size -= tail_size; } #else if ( mprotect((caddr_t)address, size, PROT_NONE) < 0 ) mprotectFailed(); #endif } /* Function: Page_Delete * * Free's DUMA allocated memory. This is the real deal, make sure * the page is no longer in our slot list first! * * See Also: * */ static void Page_Delete(void * address, size_t size) { #if defined(WIN32) void * alloc_address = address; SIZE_T retQuery; MEMORY_BASIC_INFORMATION MemInfo; BOOL ret; /* release physical memory commited to virtual address space */ while (size >0) { retQuery = VirtualQuery(address, &MemInfo, sizeof(MemInfo)); if (retQuery < sizeof(MemInfo)) DUMA_Abort("VirtualQuery() failed\n"); if ( MemInfo.State == MEM_COMMIT ) { ret = VirtualFree( (LPVOID) MemInfo.BaseAddress /* base of committed pages */ , (DWORD) MemInfo.RegionSize /* size of the region */ , (DWORD) MEM_DECOMMIT /* type of free operation */ ); if (0 == ret) DUMA_Abort("VirtualFree(,,MEM_DECOMMIT) failed: %s", stringErrorReport()); } address = ((char *)address) + MemInfo.RegionSize; size -= MemInfo.RegionSize; } /* release virtual address space */ ret = VirtualFree( (LPVOID) alloc_address , (DWORD) 0 , (DWORD) MEM_RELEASE ); if (0 == ret) DUMA_Abort("VirtualFree(,,MEM_RELEASE) failed: %s", stringErrorReport()); #else if ( munmap((caddr_t)address, size) < 0 ) Page_DenyAccess(address, size); #endif } /* Function: Page_Size * * Retrieve page size. */ static size_t Page_Size(void) { #if defined(WIN32) SYSTEM_INFO SystemInfo; GetSystemInfo( &SystemInfo ); return (size_t)SystemInfo.dwPageSize; #elif defined(_SC_PAGESIZE) return (size_t)sysconf(_SC_PAGESIZE); #elif defined(_SC_PAGE_SIZE) return (size_t)sysconf(_SC_PAGE_SIZE); #else /* extern int getpagesize(); */ return getpagesize(); #endif } #endif /* DUMA_PAGING_H */