/* | |
* Copyright (C) 2008 Apple Inc. All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without | |
* modification, are permitted provided that the following conditions | |
* are met: | |
* 1. Redistributions of source code must retain the above copyright | |
* notice, this list of conditions and the following disclaimer. | |
* 2. Redistributions in binary form must reproduce the above copyright | |
* notice, this list of conditions and the following disclaimer in the | |
* documentation and/or other materials provided with the distribution. | |
* | |
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY | |
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | |
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR | |
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY | |
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
*/ | |
#include "config.h" | |
#include "ExecutableAllocator.h" | |
#if ENABLE(ASSEMBLER) && OS(UNIX) && !OS(SYMBIAN) | |
#include <sys/mman.h> | |
#include <unistd.h> | |
#include <wtf/VMTags.h> | |
namespace JSC { | |
#if !(OS(DARWIN) && CPU(X86_64)) | |
void ExecutableAllocator::intializePageSize() | |
{ | |
ExecutableAllocator::pageSize = getpagesize(); | |
} | |
ExecutablePool::Allocation ExecutablePool::systemAlloc(size_t n) | |
{ | |
void* allocation = mmap(NULL, n, INITIAL_PROTECTION_FLAGS, MAP_PRIVATE | MAP_ANON, VM_TAG_FOR_EXECUTABLEALLOCATOR_MEMORY, 0); | |
if (allocation == MAP_FAILED) | |
CRASH(); | |
ExecutablePool::Allocation alloc = { reinterpret_cast<char*>(allocation), n }; | |
return alloc; | |
} | |
void ExecutablePool::systemRelease(const ExecutablePool::Allocation& alloc) | |
{ | |
int result = munmap(alloc.pages, alloc.size); | |
ASSERT_UNUSED(result, !result); | |
} | |
#endif // !(OS(DARWIN) && CPU(X86_64)) | |
#if ENABLE(ASSEMBLER_WX_EXCLUSIVE) | |
void ExecutableAllocator::reprotectRegion(void* start, size_t size, ProtectionSeting setting) | |
{ | |
if (!pageSize) | |
intializePageSize(); | |
// Calculate the start of the page containing this region, | |
// and account for this extra memory within size. | |
intptr_t startPtr = reinterpret_cast<intptr_t>(start); | |
intptr_t pageStartPtr = startPtr & ~(pageSize - 1); | |
void* pageStart = reinterpret_cast<void*>(pageStartPtr); | |
size += (startPtr - pageStartPtr); | |
// Round size up | |
size += (pageSize - 1); | |
size &= ~(pageSize - 1); | |
mprotect(pageStart, size, (setting == Writable) ? PROTECTION_FLAGS_RW : PROTECTION_FLAGS_RX); | |
} | |
#endif | |
} | |
#endif // HAVE(ASSEMBLER) |