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Diffstat (limited to 'JavaScriptCore/wtf/OSAllocatorPosix.cpp')
-rw-r--r-- | JavaScriptCore/wtf/OSAllocatorPosix.cpp | 121 |
1 files changed, 0 insertions, 121 deletions
diff --git a/JavaScriptCore/wtf/OSAllocatorPosix.cpp b/JavaScriptCore/wtf/OSAllocatorPosix.cpp deleted file mode 100644 index 5546cef..0000000 --- a/JavaScriptCore/wtf/OSAllocatorPosix.cpp +++ /dev/null @@ -1,121 +0,0 @@ -/* - * Copyright (C) 2010 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. AND ITS CONTRIBUTORS ``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 ITS 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 "OSAllocator.h" - -#include <errno.h> -#include <sys/mman.h> -#include <wtf/Assertions.h> -#include <wtf/UnusedParam.h> - -namespace WTF { - -void* OSAllocator::reserveUncommitted(size_t bytes, Usage usage, bool writable, bool executable) -{ - void* result = reserveAndCommit(bytes, usage, writable, executable); -#if HAVE(MADV_FREE_REUSE) - // To support the "reserve then commit" model, we have to initially decommit. - while (madvise(result, bytes, MADV_FREE_REUSABLE) == -1 && errno == EAGAIN) { } -#endif - return result; -} - -void* OSAllocator::reserveAndCommit(size_t bytes, Usage usage, bool writable, bool executable) -{ - // All POSIX reservations start out logically committed. - int protection = PROT_READ; - if (writable) - protection |= PROT_WRITE; - if (executable) - protection |= PROT_EXEC; - - int flags = MAP_PRIVATE | MAP_ANON; - -#if OS(DARWIN) && !defined(BUILDING_ON_TIGER) - int fd = usage; -#else - int fd = -1; -#endif - - void* result = 0; -#if (OS(DARWIN) && CPU(X86_64)) - if (executable) { - // Cook up an address to allocate at, using the following recipe: - // 17 bits of zero, stay in userspace kids. - // 26 bits of randomness for ASLR. - // 21 bits of zero, at least stay aligned within one level of the pagetables. - // - // But! - as a temporary workaround for some plugin problems (rdar://problem/6812854), - // for now instead of 2^26 bits of ASLR lets stick with 25 bits of randomization plus - // 2^24, which should put up somewhere in the middle of userspace (in the address range - // 0x200000000000 .. 0x5fffffffffff). - intptr_t randomLocation = 0; - randomLocation = arc4random() & ((1 << 25) - 1); - randomLocation += (1 << 24); - randomLocation <<= 21; - result = reinterpret_cast<void*>(randomLocation); - } -#endif - - result = mmap(result, bytes, protection, flags, fd, 0); - if (result == MAP_FAILED) - CRASH(); - return result; -} - -void OSAllocator::commit(void* address, size_t bytes, bool, bool) -{ -#if HAVE(MADV_FREE_REUSE) - while (madvise(address, bytes, MADV_FREE_REUSE) == -1 && errno == EAGAIN) { } -#else - // Non-MADV_FREE_REUSE reservations automatically commit on demand. - UNUSED_PARAM(address); - UNUSED_PARAM(bytes); -#endif -} - -void OSAllocator::decommit(void* address, size_t bytes) -{ -#if HAVE(MADV_FREE_REUSE) - while (madvise(address, bytes, MADV_FREE_REUSABLE) == -1 && errno == EAGAIN) { } -#elif HAVE(MADV_FREE) - while (madvise(address, bytes, MADV_FREE) == -1 && errno == EAGAIN) { } -#elif HAVE(MADV_DONTNEED) - while (madvise(address, bytes, MADV_DONTNEED) == -1 && errno == EAGAIN) { } -#else - UNUSED_PARAM(address); - UNUSED_PARAM(bytes); -#endif -} - -void OSAllocator::releaseDecommitted(void* address, size_t bytes) -{ - int result = munmap(address, bytes); - if (result == -1) - CRASH(); -} - -} // namespace WTF |