Index: third_party/WebKit/Source/wtf/allocator/PageAllocator.cpp |
diff --git a/third_party/WebKit/Source/wtf/allocator/PageAllocator.cpp b/third_party/WebKit/Source/wtf/allocator/PageAllocator.cpp |
deleted file mode 100644 |
index 22e12d33c72d53cdf08139fba66f8a6c07e4050b..0000000000000000000000000000000000000000 |
--- a/third_party/WebKit/Source/wtf/allocator/PageAllocator.cpp |
+++ /dev/null |
@@ -1,298 +0,0 @@ |
-/* |
- * Copyright (C) 2013 Google 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: |
- * |
- * * Redistributions of source code must retain the above copyright |
- * notice, this list of conditions and the following disclaimer. |
- * * 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. |
- * * Neither the name of Google Inc. nor the names of its |
- * contributors may be used to endorse or promote products derived from |
- * this software without specific prior written permission. |
- * |
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT |
- * OWNER 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 "wtf/allocator/PageAllocator.h" |
- |
-#include "wtf/Assertions.h" |
-#include "wtf/Atomics.h" |
-#include "wtf/allocator/AddressSpaceRandomization.h" |
- |
-#include <limits.h> |
- |
-#if OS(POSIX) |
- |
-#include <errno.h> |
-#include <sys/mman.h> |
- |
-#ifndef MADV_FREE |
-#define MADV_FREE MADV_DONTNEED |
-#endif |
- |
-#ifndef MAP_ANONYMOUS |
-#define MAP_ANONYMOUS MAP_ANON |
-#endif |
- |
-// On POSIX memmap uses a nearby address if the hint address is blocked. |
-static const bool kHintIsAdvisory = true; |
-static uint32_t s_allocPageErrorCode = 0; |
- |
-#elif OS(WIN) |
- |
-#include <windows.h> |
- |
-// VirtualAlloc will fail if allocation at the hint address is blocked. |
-static const bool kHintIsAdvisory = false; |
-static uint32_t s_allocPageErrorCode = ERROR_SUCCESS; |
- |
-#else |
-#error Unknown OS |
-#endif // OS(POSIX) |
- |
-namespace WTF { |
- |
-// This internal function wraps the OS-specific page allocation call. The |
-// behavior of the hint address is determined by the kHintIsAdvisory constant. |
-// If true, a non-zero hint is advisory and the returned address may differ from |
-// the hint. If false, the hint is mandatory and a successful allocation will |
-// not differ from the hint. |
-static void* systemAllocPages( |
- void* hint, |
- size_t len, |
- PageAccessibilityConfiguration pageAccessibility) { |
- ASSERT(!(len & kPageAllocationGranularityOffsetMask)); |
- ASSERT(!(reinterpret_cast<uintptr_t>(hint) & |
- kPageAllocationGranularityOffsetMask)); |
- void* ret; |
-#if OS(WIN) |
- DWORD accessFlag = |
- pageAccessibility == PageAccessible ? PAGE_READWRITE : PAGE_NOACCESS; |
- ret = VirtualAlloc(hint, len, MEM_RESERVE | MEM_COMMIT, accessFlag); |
- if (!ret) |
- releaseStore(&s_allocPageErrorCode, GetLastError()); |
-#else |
- int accessFlag = pageAccessibility == PageAccessible |
- ? (PROT_READ | PROT_WRITE) |
- : PROT_NONE; |
- ret = mmap(hint, len, accessFlag, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); |
- if (ret == MAP_FAILED) { |
- releaseStore(&s_allocPageErrorCode, errno); |
- ret = 0; |
- } |
-#endif |
- return ret; |
-} |
- |
-// Trims base to given length and alignment. Windows returns null on failure and |
-// frees base. |
-static void* trimMapping(void* base, |
- size_t baseLen, |
- size_t trimLen, |
- uintptr_t align, |
- PageAccessibilityConfiguration pageAccessibility) { |
- size_t preSlack = reinterpret_cast<uintptr_t>(base) & (align - 1); |
- if (preSlack) |
- preSlack = align - preSlack; |
- size_t postSlack = baseLen - preSlack - trimLen; |
- ASSERT(baseLen >= trimLen || preSlack || postSlack); |
- ASSERT(preSlack < baseLen); |
- ASSERT(postSlack < baseLen); |
- void* ret = base; |
- |
-#if OS(POSIX) // On POSIX we can resize the allocation run. |
- (void)pageAccessibility; |
- if (preSlack) { |
- int res = munmap(base, preSlack); |
- RELEASE_ASSERT(!res); |
- ret = reinterpret_cast<char*>(base) + preSlack; |
- } |
- if (postSlack) { |
- int res = munmap(reinterpret_cast<char*>(ret) + trimLen, postSlack); |
- RELEASE_ASSERT(!res); |
- } |
-#else // On Windows we can't resize the allocation run. |
- if (preSlack || postSlack) { |
- ret = reinterpret_cast<char*>(base) + preSlack; |
- freePages(base, baseLen); |
- ret = systemAllocPages(ret, trimLen, pageAccessibility); |
- } |
-#endif |
- |
- return ret; |
-} |
- |
-void* allocPages(void* addr, |
- size_t len, |
- size_t align, |
- PageAccessibilityConfiguration pageAccessibility) { |
- ASSERT(len >= kPageAllocationGranularity); |
- ASSERT(!(len & kPageAllocationGranularityOffsetMask)); |
- ASSERT(align >= kPageAllocationGranularity); |
- ASSERT(!(align & kPageAllocationGranularityOffsetMask)); |
- ASSERT(!(reinterpret_cast<uintptr_t>(addr) & |
- kPageAllocationGranularityOffsetMask)); |
- uintptr_t alignOffsetMask = align - 1; |
- uintptr_t alignBaseMask = ~alignOffsetMask; |
- ASSERT(!(reinterpret_cast<uintptr_t>(addr) & alignOffsetMask)); |
- |
- // If the client passed null as the address, choose a good one. |
- if (!addr) { |
- addr = getRandomPageBase(); |
- addr = reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(addr) & |
- alignBaseMask); |
- } |
- |
- // First try to force an exact-size, aligned allocation from our random base. |
- for (int count = 0; count < 3; ++count) { |
- void* ret = systemAllocPages(addr, len, pageAccessibility); |
- if (kHintIsAdvisory || ret) { |
- // If the alignment is to our liking, we're done. |
- if (!(reinterpret_cast<uintptr_t>(ret) & alignOffsetMask)) |
- return ret; |
- freePages(ret, len); |
-#if CPU(32BIT) |
- addr = reinterpret_cast<void*>( |
- (reinterpret_cast<uintptr_t>(ret) + align) & alignBaseMask); |
-#endif |
- } else if (!addr) { // We know we're OOM when an unhinted allocation fails. |
- return nullptr; |
- |
- } else { |
-#if CPU(32BIT) |
- addr = reinterpret_cast<char*>(addr) + align; |
-#endif |
- } |
- |
-#if !CPU(32BIT) |
- // Keep trying random addresses on systems that have a large address space. |
- addr = getRandomPageBase(); |
- addr = reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(addr) & |
- alignBaseMask); |
-#endif |
- } |
- |
- // Map a larger allocation so we can force alignment, but continue randomizing |
- // only on 64-bit POSIX. |
- size_t tryLen = len + (align - kPageAllocationGranularity); |
- RELEASE_ASSERT(tryLen >= len); |
- void* ret; |
- |
- do { |
- // Don't continue to burn cycles on mandatory hints (Windows). |
- addr = kHintIsAdvisory ? getRandomPageBase() : nullptr; |
- ret = systemAllocPages(addr, tryLen, pageAccessibility); |
- // The retries are for Windows, where a race can steal our mapping on |
- // resize. |
- } while (ret && |
- !(ret = trimMapping(ret, tryLen, len, align, pageAccessibility))); |
- |
- return ret; |
-} |
- |
-void freePages(void* addr, size_t len) { |
- ASSERT(!(reinterpret_cast<uintptr_t>(addr) & |
- kPageAllocationGranularityOffsetMask)); |
- ASSERT(!(len & kPageAllocationGranularityOffsetMask)); |
-#if OS(POSIX) |
- int ret = munmap(addr, len); |
- RELEASE_ASSERT(!ret); |
-#else |
- BOOL ret = VirtualFree(addr, 0, MEM_RELEASE); |
- RELEASE_ASSERT(ret); |
-#endif |
-} |
- |
-void setSystemPagesInaccessible(void* addr, size_t len) { |
- ASSERT(!(len & kSystemPageOffsetMask)); |
-#if OS(POSIX) |
- int ret = mprotect(addr, len, PROT_NONE); |
- RELEASE_ASSERT(!ret); |
-#else |
- BOOL ret = VirtualFree(addr, len, MEM_DECOMMIT); |
- RELEASE_ASSERT(ret); |
-#endif |
-} |
- |
-bool setSystemPagesAccessible(void* addr, size_t len) { |
- ASSERT(!(len & kSystemPageOffsetMask)); |
-#if OS(POSIX) |
- return !mprotect(addr, len, PROT_READ | PROT_WRITE); |
-#else |
- return !!VirtualAlloc(addr, len, MEM_COMMIT, PAGE_READWRITE); |
-#endif |
-} |
- |
-void decommitSystemPages(void* addr, size_t len) { |
- ASSERT(!(len & kSystemPageOffsetMask)); |
-#if OS(POSIX) |
- int ret = madvise(addr, len, MADV_FREE); |
- RELEASE_ASSERT(!ret); |
-#else |
- setSystemPagesInaccessible(addr, len); |
-#endif |
-} |
- |
-void recommitSystemPages(void* addr, size_t len) { |
- ASSERT(!(len & kSystemPageOffsetMask)); |
-#if OS(POSIX) |
- (void)addr; |
-#else |
- RELEASE_ASSERT(setSystemPagesAccessible(addr, len)); |
-#endif |
-} |
- |
-void discardSystemPages(void* addr, size_t len) { |
- ASSERT(!(len & kSystemPageOffsetMask)); |
-#if OS(POSIX) |
- // On POSIX, the implementation detail is that discard and decommit are the |
- // same, and lead to pages that are returned to the system immediately and |
- // get replaced with zeroed pages when touched. So we just call |
- // decommitSystemPages() here to avoid code duplication. |
- decommitSystemPages(addr, len); |
-#else |
- // On Windows discarded pages are not returned to the system immediately and |
- // not guaranteed to be zeroed when returned to the application. |
- using DiscardVirtualMemoryFunction = |
- DWORD(WINAPI*)(PVOID virtualAddress, SIZE_T size); |
- static DiscardVirtualMemoryFunction discardVirtualMemory = |
- reinterpret_cast<DiscardVirtualMemoryFunction>(-1); |
- if (discardVirtualMemory == |
- reinterpret_cast<DiscardVirtualMemoryFunction>(-1)) |
- discardVirtualMemory = |
- reinterpret_cast<DiscardVirtualMemoryFunction>(GetProcAddress( |
- GetModuleHandle(L"Kernel32.dll"), "DiscardVirtualMemory")); |
- // Use DiscardVirtualMemory when available because it releases faster than |
- // MEM_RESET. |
- DWORD ret = 1; |
- if (discardVirtualMemory) |
- ret = discardVirtualMemory(addr, len); |
- // DiscardVirtualMemory is buggy in Win10 SP0, so fall back to MEM_RESET on |
- // failure. |
- if (ret) { |
- void* ret = VirtualAlloc(addr, len, MEM_RESET, PAGE_READWRITE); |
- RELEASE_ASSERT(ret); |
- } |
-#endif |
-} |
- |
-uint32_t getAllocPageErrorCode() { |
- return acquireLoad(&s_allocPageErrorCode); |
-} |
- |
-} // namespace WTF |