683 lines
24 KiB
C++
683 lines
24 KiB
C++
/*
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* Copyright (C) 2008 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include "mem_map.h"
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#include "thread-inl.h"
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#include <inttypes.h>
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#include <backtrace/BacktraceMap.h>
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#include <memory>
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// See CreateStartPos below.
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#ifdef __BIONIC__
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#include <sys/auxv.h>
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#endif
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#include "base/stringprintf.h"
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#include "ScopedFd.h"
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#include "utils.h"
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#define USE_ASHMEM 1
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#ifdef USE_ASHMEM
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#include <cutils/ashmem.h>
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#ifndef ANDROID_OS
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#include <sys/resource.h>
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#endif
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#endif
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#ifndef MAP_ANONYMOUS
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#define MAP_ANONYMOUS MAP_ANON
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#endif
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namespace art {
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static std::ostream& operator<<(
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std::ostream& os,
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std::pair<BacktraceMap::const_iterator, BacktraceMap::const_iterator> iters) {
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for (BacktraceMap::const_iterator it = iters.first; it != iters.second; ++it) {
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os << StringPrintf("0x%08x-0x%08x %c%c%c %s\n",
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static_cast<uint32_t>(it->start),
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static_cast<uint32_t>(it->end),
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(it->flags & PROT_READ) ? 'r' : '-',
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(it->flags & PROT_WRITE) ? 'w' : '-',
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(it->flags & PROT_EXEC) ? 'x' : '-', it->name.c_str());
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}
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return os;
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}
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std::ostream& operator<<(std::ostream& os, const MemMap::Maps& mem_maps) {
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os << "MemMap:" << std::endl;
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for (auto it = mem_maps.begin(); it != mem_maps.end(); ++it) {
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void* base = it->first;
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MemMap* map = it->second;
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CHECK_EQ(base, map->BaseBegin());
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os << *map << std::endl;
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}
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return os;
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}
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MemMap::Maps* MemMap::maps_ = nullptr;
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#if USE_ART_LOW_4G_ALLOCATOR
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// Handling mem_map in 32b address range for 64b architectures that do not support MAP_32BIT.
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// The regular start of memory allocations. The first 64KB is protected by SELinux.
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static constexpr uintptr_t LOW_MEM_START = 64 * KB;
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// Generate random starting position.
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// To not interfere with image position, take the image's address and only place it below. Current
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// formula (sketch):
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//
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// ART_BASE_ADDR = 0001XXXXXXXXXXXXXXX
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// ----------------------------------------
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// = 0000111111111111111
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// & ~(kPageSize - 1) =~0000000000000001111
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// ----------------------------------------
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// mask = 0000111111111110000
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// & random data = YYYYYYYYYYYYYYYYYYY
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// -----------------------------------
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// tmp = 0000YYYYYYYYYYY0000
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// + LOW_MEM_START = 0000000000001000000
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// --------------------------------------
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// start
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//
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// getauxval as an entropy source is exposed in Bionic, but not in glibc before 2.16. When we
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// do not have Bionic, simply start with LOW_MEM_START.
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// Function is standalone so it can be tested somewhat in mem_map_test.cc.
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#ifdef __BIONIC__
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uintptr_t CreateStartPos(uint64_t input) {
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CHECK_NE(0, ART_BASE_ADDRESS);
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// Start with all bits below highest bit in ART_BASE_ADDRESS.
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constexpr size_t leading_zeros = CLZ(static_cast<uint32_t>(ART_BASE_ADDRESS));
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constexpr uintptr_t mask_ones = (1 << (31 - leading_zeros)) - 1;
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// Lowest (usually 12) bits are not used, as aligned by page size.
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constexpr uintptr_t mask = mask_ones & ~(kPageSize - 1);
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// Mask input data.
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return (input & mask) + LOW_MEM_START;
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}
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#endif
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static uintptr_t GenerateNextMemPos() {
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#ifdef __BIONIC__
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uint8_t* random_data = reinterpret_cast<uint8_t*>(getauxval(AT_RANDOM));
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// The lower 8B are taken for the stack guard. Use the upper 8B (with mask).
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return CreateStartPos(*reinterpret_cast<uintptr_t*>(random_data + 8));
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#else
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// No auxv on host, see above.
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return LOW_MEM_START;
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#endif
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}
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// Initialize linear scan to random position.
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uintptr_t MemMap::next_mem_pos_ = GenerateNextMemPos();
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#endif
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#if !defined(__APPLE__) // TODO: Reanable after b/16861075 BacktraceMap issue is addressed.
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// Return true if the address range is contained in a single /proc/self/map entry.
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static bool ContainedWithinExistingMap(uintptr_t begin,
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uintptr_t end,
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std::string* error_msg) {
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std::unique_ptr<BacktraceMap> map(BacktraceMap::Create(getpid(), true));
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if (map.get() == nullptr) {
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*error_msg = StringPrintf("Failed to build process map");
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return false;
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}
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for (BacktraceMap::const_iterator it = map->begin(); it != map->end(); ++it) {
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if ((begin >= it->start && begin < it->end) // start of new within old
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&& (end > it->start && end <= it->end)) { // end of new within old
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return true;
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}
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}
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std::string maps;
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ReadFileToString("/proc/self/maps", &maps);
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*error_msg = StringPrintf("Requested region 0x%08" PRIxPTR "-0x%08" PRIxPTR " does not overlap "
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"any existing map:\n%s\n",
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begin, end, maps.c_str());
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return false;
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}
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#endif
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// Return true if the address range does not conflict with any /proc/self/maps entry.
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static bool CheckNonOverlapping(uintptr_t begin,
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uintptr_t end,
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std::string* error_msg) {
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std::unique_ptr<BacktraceMap> map(BacktraceMap::Create(getpid(), true));
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if (map.get() == nullptr) {
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*error_msg = StringPrintf("Failed to build process map");
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return false;
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}
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for (BacktraceMap::const_iterator it = map->begin(); it != map->end(); ++it) {
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if ((begin >= it->start && begin < it->end) // start of new within old
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|| (end > it->start && end < it->end) // end of new within old
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|| (begin <= it->start && end > it->end)) { // start/end of new includes all of old
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std::ostringstream map_info;
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map_info << std::make_pair(it, map->end());
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*error_msg = StringPrintf("Requested region 0x%08" PRIxPTR "-0x%08" PRIxPTR " overlaps with "
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"existing map 0x%08" PRIxPTR "-0x%08" PRIxPTR " (%s)\n%s",
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begin, end,
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static_cast<uintptr_t>(it->start), static_cast<uintptr_t>(it->end),
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it->name.c_str(),
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map_info.str().c_str());
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return false;
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}
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}
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return true;
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}
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// CheckMapRequest to validate a non-MAP_FAILED mmap result based on
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// the expected value, calling munmap if validation fails, giving the
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// reason in error_msg.
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//
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// If the expected_ptr is nullptr, nothing is checked beyond the fact
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// that the actual_ptr is not MAP_FAILED. However, if expected_ptr is
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// non-null, we check that pointer is the actual_ptr == expected_ptr,
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// and if not, report in error_msg what the conflict mapping was if
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// found, or a generic error in other cases.
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static bool CheckMapRequest(byte* expected_ptr, void* actual_ptr, size_t byte_count,
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std::string* error_msg) {
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// Handled first by caller for more specific error messages.
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CHECK(actual_ptr != MAP_FAILED);
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if (expected_ptr == nullptr) {
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return true;
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}
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uintptr_t actual = reinterpret_cast<uintptr_t>(actual_ptr);
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uintptr_t expected = reinterpret_cast<uintptr_t>(expected_ptr);
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uintptr_t limit = expected + byte_count;
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if (expected_ptr == actual_ptr) {
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return true;
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}
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// We asked for an address but didn't get what we wanted, all paths below here should fail.
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int result = munmap(actual_ptr, byte_count);
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if (result == -1) {
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PLOG(WARNING) << StringPrintf("munmap(%p, %zd) failed", actual_ptr, byte_count);
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}
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// We call this here so that we can try and generate a full error
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// message with the overlapping mapping. There's no guarantee that
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// that there will be an overlap though, since
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// - The kernel is not *required* to honour expected_ptr unless MAP_FIXED is
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// true, even if there is no overlap
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// - There might have been an overlap at the point of mmap, but the
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// overlapping region has since been unmapped.
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std::string error_detail;
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CheckNonOverlapping(expected, limit, &error_detail);
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std::ostringstream os;
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os << StringPrintf("Failed to mmap at expected address, mapped at "
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"0x%08" PRIxPTR " instead of 0x%08" PRIxPTR,
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actual, expected);
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if (!error_detail.empty()) {
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os << " : " << error_detail;
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}
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*error_msg = os.str();
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return false;
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}
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MemMap* MemMap::MapAnonymous(const char* name, byte* expected_ptr, size_t byte_count, int prot,
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bool low_4gb, std::string* error_msg) {
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if (byte_count == 0) {
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return new MemMap(name, nullptr, 0, nullptr, 0, prot, false);
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}
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size_t page_aligned_byte_count = RoundUp(byte_count, kPageSize);
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int flags = MAP_PRIVATE | MAP_ANONYMOUS;
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ScopedFd fd(-1);
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#ifdef USE_ASHMEM
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#ifdef HAVE_ANDROID_OS
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const bool use_ashmem = true;
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#else
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// When not on Android ashmem is faked using files in /tmp. Ensure that such files won't
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// fail due to ulimit restrictions. If they will then use a regular mmap.
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struct rlimit rlimit_fsize;
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CHECK_EQ(getrlimit(RLIMIT_FSIZE, &rlimit_fsize), 0);
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const bool use_ashmem = (rlimit_fsize.rlim_cur == RLIM_INFINITY) ||
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(page_aligned_byte_count < rlimit_fsize.rlim_cur);
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#endif
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if (use_ashmem) {
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// android_os_Debug.cpp read_mapinfo assumes all ashmem regions associated with the VM are
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// prefixed "dalvik-".
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std::string debug_friendly_name("dalvik-");
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debug_friendly_name += name;
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fd.reset(ashmem_create_region(debug_friendly_name.c_str(), page_aligned_byte_count));
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if (fd.get() == -1) {
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*error_msg = StringPrintf("ashmem_create_region failed for '%s': %s", name, strerror(errno));
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return nullptr;
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}
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flags = MAP_PRIVATE;
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}
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#endif
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// We need to store and potentially set an error number for pretty printing of errors
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int saved_errno = 0;
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#ifdef __LP64__
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// When requesting low_4g memory and having an expectation, the requested range should fit into
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// 4GB.
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if (low_4gb && (
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// Start out of bounds.
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(reinterpret_cast<uintptr_t>(expected_ptr) >> 32) != 0 ||
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// End out of bounds. For simplicity, this will fail for the last page of memory.
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(reinterpret_cast<uintptr_t>(expected_ptr + page_aligned_byte_count) >> 32) != 0)) {
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*error_msg = StringPrintf("The requested address space (%p, %p) cannot fit in low_4gb",
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expected_ptr, expected_ptr + page_aligned_byte_count);
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return nullptr;
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}
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#endif
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// TODO:
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// A page allocator would be a useful abstraction here, as
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// 1) It is doubtful that MAP_32BIT on x86_64 is doing the right job for us
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// 2) The linear scheme, even with simple saving of the last known position, is very crude
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#if USE_ART_LOW_4G_ALLOCATOR
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// MAP_32BIT only available on x86_64.
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void* actual = MAP_FAILED;
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if (low_4gb && expected_ptr == nullptr) {
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bool first_run = true;
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for (uintptr_t ptr = next_mem_pos_; ptr < 4 * GB; ptr += kPageSize) {
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if (4U * GB - ptr < page_aligned_byte_count) {
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// Not enough memory until 4GB.
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if (first_run) {
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// Try another time from the bottom;
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ptr = LOW_MEM_START - kPageSize;
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first_run = false;
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continue;
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} else {
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// Second try failed.
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break;
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}
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}
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uintptr_t tail_ptr;
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// Check pages are free.
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bool safe = true;
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for (tail_ptr = ptr; tail_ptr < ptr + page_aligned_byte_count; tail_ptr += kPageSize) {
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if (msync(reinterpret_cast<void*>(tail_ptr), kPageSize, 0) == 0) {
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safe = false;
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break;
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} else {
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DCHECK_EQ(errno, ENOMEM);
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}
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}
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next_mem_pos_ = tail_ptr; // update early, as we break out when we found and mapped a region
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if (safe == true) {
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actual = mmap(reinterpret_cast<void*>(ptr), page_aligned_byte_count, prot, flags, fd.get(),
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0);
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if (actual != MAP_FAILED) {
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// Since we didn't use MAP_FIXED the kernel may have mapped it somewhere not in the low
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// 4GB. If this is the case, unmap and retry.
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if (reinterpret_cast<uintptr_t>(actual) + page_aligned_byte_count < 4 * GB) {
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break;
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} else {
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munmap(actual, page_aligned_byte_count);
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actual = MAP_FAILED;
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}
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}
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} else {
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// Skip over last page.
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ptr = tail_ptr;
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}
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}
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if (actual == MAP_FAILED) {
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LOG(ERROR) << "Could not find contiguous low-memory space.";
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saved_errno = ENOMEM;
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}
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} else {
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actual = mmap(expected_ptr, page_aligned_byte_count, prot, flags, fd.get(), 0);
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saved_errno = errno;
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}
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#else
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#if defined(__LP64__)
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if (low_4gb && expected_ptr == nullptr) {
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flags |= MAP_32BIT;
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}
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#endif
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void* actual = mmap(expected_ptr, page_aligned_byte_count, prot, flags, fd.get(), 0);
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saved_errno = errno;
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#endif
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if (actual == MAP_FAILED) {
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std::string maps;
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ReadFileToString("/proc/self/maps", &maps);
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*error_msg = StringPrintf("Failed anonymous mmap(%p, %zd, 0x%x, 0x%x, %d, 0): %s\n%s",
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expected_ptr, page_aligned_byte_count, prot, flags, fd.get(),
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strerror(saved_errno), maps.c_str());
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return nullptr;
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}
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std::ostringstream check_map_request_error_msg;
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if (!CheckMapRequest(expected_ptr, actual, page_aligned_byte_count, error_msg)) {
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return nullptr;
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}
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return new MemMap(name, reinterpret_cast<byte*>(actual), byte_count, actual,
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page_aligned_byte_count, prot, false);
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}
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MemMap* MemMap::MapFileAtAddress(byte* expected_ptr, size_t byte_count, int prot, int flags, int fd,
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off_t start, bool reuse, const char* filename,
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std::string* error_msg) {
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CHECK_NE(0, prot);
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CHECK_NE(0, flags & (MAP_SHARED | MAP_PRIVATE));
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// Note that we do not allow MAP_FIXED unless reuse == true, i.e we
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// expect his mapping to be contained within an existing map.
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if (reuse) {
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// reuse means it is okay that it overlaps an existing page mapping.
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// Only use this if you actually made the page reservation yourself.
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CHECK(expected_ptr != nullptr);
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#if !defined(__APPLE__) // TODO: Reanable after b/16861075 BacktraceMap issue is addressed.
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uintptr_t expected = reinterpret_cast<uintptr_t>(expected_ptr);
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uintptr_t limit = expected + byte_count;
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DCHECK(ContainedWithinExistingMap(expected, limit, error_msg));
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#endif
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flags |= MAP_FIXED;
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} else {
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CHECK_EQ(0, flags & MAP_FIXED);
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// Don't bother checking for an overlapping region here. We'll
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// check this if required after the fact inside CheckMapRequest.
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}
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if (byte_count == 0) {
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return new MemMap(filename, nullptr, 0, nullptr, 0, prot, false);
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}
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// Adjust 'offset' to be page-aligned as required by mmap.
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int page_offset = start % kPageSize;
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off_t page_aligned_offset = start - page_offset;
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// Adjust 'byte_count' to be page-aligned as we will map this anyway.
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size_t page_aligned_byte_count = RoundUp(byte_count + page_offset, kPageSize);
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// The 'expected_ptr' is modified (if specified, ie non-null) to be page aligned to the file but
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// not necessarily to virtual memory. mmap will page align 'expected' for us.
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byte* page_aligned_expected = (expected_ptr == nullptr) ? nullptr : (expected_ptr - page_offset);
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byte* actual = reinterpret_cast<byte*>(mmap(page_aligned_expected,
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page_aligned_byte_count,
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prot,
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flags,
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fd,
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page_aligned_offset));
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if (actual == MAP_FAILED) {
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auto saved_errno = errno;
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std::string maps;
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ReadFileToString("/proc/self/maps", &maps);
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*error_msg = StringPrintf("mmap(%p, %zd, 0x%x, 0x%x, %d, %" PRId64
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") of file '%s' failed: %s\n%s",
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page_aligned_expected, page_aligned_byte_count, prot, flags, fd,
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static_cast<int64_t>(page_aligned_offset), filename,
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strerror(saved_errno), maps.c_str());
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return nullptr;
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}
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std::ostringstream check_map_request_error_msg;
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if (!CheckMapRequest(expected_ptr, actual, page_aligned_byte_count, error_msg)) {
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return nullptr;
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}
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return new MemMap(filename, actual + page_offset, byte_count, actual, page_aligned_byte_count,
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prot, reuse);
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}
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MemMap::~MemMap() {
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if (base_begin_ == nullptr && base_size_ == 0) {
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return;
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}
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if (!reuse_) {
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int result = munmap(base_begin_, base_size_);
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if (result == -1) {
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PLOG(FATAL) << "munmap failed";
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}
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}
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// Remove it from maps_.
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MutexLock mu(Thread::Current(), *Locks::mem_maps_lock_);
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bool found = false;
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DCHECK(maps_ != nullptr);
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for (auto it = maps_->lower_bound(base_begin_), end = maps_->end();
|
|
it != end && it->first == base_begin_; ++it) {
|
|
if (it->second == this) {
|
|
found = true;
|
|
maps_->erase(it);
|
|
break;
|
|
}
|
|
}
|
|
CHECK(found) << "MemMap not found";
|
|
}
|
|
|
|
MemMap::MemMap(const std::string& name, byte* begin, size_t size, void* base_begin,
|
|
size_t base_size, int prot, bool reuse)
|
|
: name_(name), begin_(begin), size_(size), base_begin_(base_begin), base_size_(base_size),
|
|
prot_(prot), reuse_(reuse) {
|
|
if (size_ == 0) {
|
|
CHECK(begin_ == nullptr);
|
|
CHECK(base_begin_ == nullptr);
|
|
CHECK_EQ(base_size_, 0U);
|
|
} else {
|
|
CHECK(begin_ != nullptr);
|
|
CHECK(base_begin_ != nullptr);
|
|
CHECK_NE(base_size_, 0U);
|
|
|
|
// Add it to maps_.
|
|
MutexLock mu(Thread::Current(), *Locks::mem_maps_lock_);
|
|
DCHECK(maps_ != nullptr);
|
|
maps_->insert(std::make_pair(base_begin_, this));
|
|
}
|
|
};
|
|
|
|
MemMap* MemMap::RemapAtEnd(byte* new_end, const char* tail_name, int tail_prot,
|
|
std::string* error_msg) {
|
|
DCHECK_GE(new_end, Begin());
|
|
DCHECK_LE(new_end, End());
|
|
DCHECK_LE(begin_ + size_, reinterpret_cast<byte*>(base_begin_) + base_size_);
|
|
DCHECK(IsAligned<kPageSize>(begin_));
|
|
DCHECK(IsAligned<kPageSize>(base_begin_));
|
|
DCHECK(IsAligned<kPageSize>(reinterpret_cast<byte*>(base_begin_) + base_size_));
|
|
DCHECK(IsAligned<kPageSize>(new_end));
|
|
byte* old_end = begin_ + size_;
|
|
byte* old_base_end = reinterpret_cast<byte*>(base_begin_) + base_size_;
|
|
byte* new_base_end = new_end;
|
|
DCHECK_LE(new_base_end, old_base_end);
|
|
if (new_base_end == old_base_end) {
|
|
return new MemMap(tail_name, nullptr, 0, nullptr, 0, tail_prot, false);
|
|
}
|
|
size_ = new_end - reinterpret_cast<byte*>(begin_);
|
|
base_size_ = new_base_end - reinterpret_cast<byte*>(base_begin_);
|
|
DCHECK_LE(begin_ + size_, reinterpret_cast<byte*>(base_begin_) + base_size_);
|
|
size_t tail_size = old_end - new_end;
|
|
byte* tail_base_begin = new_base_end;
|
|
size_t tail_base_size = old_base_end - new_base_end;
|
|
DCHECK_EQ(tail_base_begin + tail_base_size, old_base_end);
|
|
DCHECK(IsAligned<kPageSize>(tail_base_size));
|
|
|
|
#ifdef USE_ASHMEM
|
|
// android_os_Debug.cpp read_mapinfo assumes all ashmem regions associated with the VM are
|
|
// prefixed "dalvik-".
|
|
std::string debug_friendly_name("dalvik-");
|
|
debug_friendly_name += tail_name;
|
|
ScopedFd fd(ashmem_create_region(debug_friendly_name.c_str(), tail_base_size));
|
|
int flags = MAP_PRIVATE | MAP_FIXED;
|
|
if (fd.get() == -1) {
|
|
*error_msg = StringPrintf("ashmem_create_region failed for '%s': %s",
|
|
tail_name, strerror(errno));
|
|
return nullptr;
|
|
}
|
|
#else
|
|
ScopedFd fd(-1);
|
|
int flags = MAP_PRIVATE | MAP_ANONYMOUS;
|
|
#endif
|
|
|
|
// Unmap/map the tail region.
|
|
int result = munmap(tail_base_begin, tail_base_size);
|
|
if (result == -1) {
|
|
std::string maps;
|
|
ReadFileToString("/proc/self/maps", &maps);
|
|
*error_msg = StringPrintf("munmap(%p, %zd) failed for '%s'\n%s",
|
|
tail_base_begin, tail_base_size, name_.c_str(),
|
|
maps.c_str());
|
|
return nullptr;
|
|
}
|
|
// Don't cause memory allocation between the munmap and the mmap
|
|
// calls. Otherwise, libc (or something else) might take this memory
|
|
// region. Note this isn't perfect as there's no way to prevent
|
|
// other threads to try to take this memory region here.
|
|
byte* actual = reinterpret_cast<byte*>(mmap(tail_base_begin, tail_base_size, tail_prot,
|
|
flags, fd.get(), 0));
|
|
if (actual == MAP_FAILED) {
|
|
std::string maps;
|
|
ReadFileToString("/proc/self/maps", &maps);
|
|
*error_msg = StringPrintf("anonymous mmap(%p, %zd, 0x%x, 0x%x, %d, 0) failed\n%s",
|
|
tail_base_begin, tail_base_size, tail_prot, flags, fd.get(),
|
|
maps.c_str());
|
|
return nullptr;
|
|
}
|
|
return new MemMap(tail_name, actual, tail_size, actual, tail_base_size, tail_prot, false);
|
|
}
|
|
|
|
void MemMap::MadviseDontNeedAndZero() {
|
|
if (base_begin_ != nullptr || base_size_ != 0) {
|
|
if (!kMadviseZeroes) {
|
|
memset(base_begin_, 0, base_size_);
|
|
}
|
|
int result = madvise(base_begin_, base_size_, MADV_DONTNEED);
|
|
if (result == -1) {
|
|
PLOG(WARNING) << "madvise failed";
|
|
}
|
|
}
|
|
}
|
|
|
|
bool MemMap::Protect(int prot) {
|
|
if (base_begin_ == nullptr && base_size_ == 0) {
|
|
prot_ = prot;
|
|
return true;
|
|
}
|
|
|
|
if (mprotect(base_begin_, base_size_, prot) == 0) {
|
|
prot_ = prot;
|
|
return true;
|
|
}
|
|
|
|
PLOG(ERROR) << "mprotect(" << reinterpret_cast<void*>(base_begin_) << ", " << base_size_ << ", "
|
|
<< prot << ") failed";
|
|
return false;
|
|
}
|
|
|
|
bool MemMap::CheckNoGaps(MemMap* begin_map, MemMap* end_map) {
|
|
MutexLock mu(Thread::Current(), *Locks::mem_maps_lock_);
|
|
CHECK(begin_map != nullptr);
|
|
CHECK(end_map != nullptr);
|
|
CHECK(HasMemMap(begin_map));
|
|
CHECK(HasMemMap(end_map));
|
|
CHECK_LE(begin_map->BaseBegin(), end_map->BaseBegin());
|
|
MemMap* map = begin_map;
|
|
while (map->BaseBegin() != end_map->BaseBegin()) {
|
|
MemMap* next_map = GetLargestMemMapAt(map->BaseEnd());
|
|
if (next_map == nullptr) {
|
|
// Found a gap.
|
|
return false;
|
|
}
|
|
map = next_map;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void MemMap::DumpMaps(std::ostream& os) {
|
|
MutexLock mu(Thread::Current(), *Locks::mem_maps_lock_);
|
|
DumpMapsLocked(os);
|
|
}
|
|
|
|
void MemMap::DumpMapsLocked(std::ostream& os) {
|
|
os << maps_;
|
|
}
|
|
|
|
bool MemMap::HasMemMap(MemMap* map) {
|
|
void* base_begin = map->BaseBegin();
|
|
for (auto it = maps_->lower_bound(base_begin), end = maps_->end();
|
|
it != end && it->first == base_begin; ++it) {
|
|
if (it->second == map) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
MemMap* MemMap::GetLargestMemMapAt(void* address) {
|
|
size_t largest_size = 0;
|
|
MemMap* largest_map = nullptr;
|
|
DCHECK(maps_ != nullptr);
|
|
for (auto it = maps_->lower_bound(address), end = maps_->end();
|
|
it != end && it->first == address; ++it) {
|
|
MemMap* map = it->second;
|
|
CHECK(map != nullptr);
|
|
if (largest_size < map->BaseSize()) {
|
|
largest_size = map->BaseSize();
|
|
largest_map = map;
|
|
}
|
|
}
|
|
return largest_map;
|
|
}
|
|
|
|
void MemMap::Init() {
|
|
MutexLock mu(Thread::Current(), *Locks::mem_maps_lock_);
|
|
if (maps_ == nullptr) {
|
|
// dex2oat calls MemMap::Init twice since its needed before the runtime is created.
|
|
maps_ = new Maps;
|
|
}
|
|
}
|
|
|
|
void MemMap::Shutdown() {
|
|
MutexLock mu(Thread::Current(), *Locks::mem_maps_lock_);
|
|
delete maps_;
|
|
maps_ = nullptr;
|
|
}
|
|
|
|
void MemMap::SetSize(size_t new_size) {
|
|
if (new_size == base_size_) {
|
|
return;
|
|
}
|
|
CHECK_ALIGNED(new_size, kPageSize);
|
|
CHECK_EQ(base_size_, size_) << "Unsupported";
|
|
CHECK_LE(new_size, base_size_);
|
|
CHECK_EQ(munmap(reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(BaseBegin()) + new_size),
|
|
base_size_ - new_size), 0) << new_size << " " << base_size_;
|
|
base_size_ = new_size;
|
|
size_ = new_size;
|
|
}
|
|
|
|
std::ostream& operator<<(std::ostream& os, const MemMap& mem_map) {
|
|
os << StringPrintf("[MemMap: %p-%p prot=0x%x %s]",
|
|
mem_map.BaseBegin(), mem_map.BaseEnd(), mem_map.GetProtect(),
|
|
mem_map.GetName().c_str());
|
|
return os;
|
|
}
|
|
|
|
} // namespace art
|