/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "MemoryDealer"
#include <hidlcache/MemoryDealer.h>
#include <hidlmemory/HidlMemoryToken.h>
#include <hidlmemory/mapping.h>
#include <list>
#include <log/log.h>
#include <errno.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/file.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
using std::string;
namespace android {
namespace hardware {
class SimpleBestFitAllocator {
enum { PAGE_ALIGNED = 0x00000001 };
public:
explicit SimpleBestFitAllocator(size_t size);
~SimpleBestFitAllocator();
size_t allocate(size_t size, uint32_t flags = 0);
status_t deallocate(size_t offset);
size_t size() const;
void dump(const char* tag) const;
void dump(string& res, const char* tag) const;
static size_t getAllocationAlignment() { return kMemoryAlign; }
private:
struct chunk_t {
chunk_t(size_t start, size_t size) : start(start), size(size), free(1) {}
size_t start;
size_t size : 28;
int free : 4;
};
using List = std::list<chunk_t*>;
using Iterator = std::list<chunk_t*>::iterator;
using IteratorConst = std::list<chunk_t*>::const_iterator;
using Mutex = std::mutex;
using Lock = std::lock_guard<Mutex>;
ssize_t alloc(size_t size, uint32_t flags);
chunk_t* dealloc(size_t start);
void dump_l(const char* tag) const;
void dump_l(string& res, const char* tag) const;
static const int kMemoryAlign;
mutable Mutex mLock;
List mList;
size_t mHeapSize;
};
MemoryDealer::MemoryDealer(size_t size) : mAllocator(new SimpleBestFitAllocator(size)) {}
MemoryDealer::~MemoryDealer() {
delete mAllocator;
}
ssize_t MemoryDealer::allocateOffset(size_t size) {
return mAllocator->allocate(size);
}
void MemoryDealer::deallocate(size_t offset) {
mAllocator->deallocate(offset);
}
void MemoryDealer::dump(const char* tag) const {
mAllocator->dump(tag);
}
size_t MemoryDealer::getAllocationAlignment() {
return SimpleBestFitAllocator::getAllocationAlignment();
}
// align all the memory blocks on a cache-line boundary
const int SimpleBestFitAllocator::kMemoryAlign = 32;
SimpleBestFitAllocator::SimpleBestFitAllocator(size_t size) {
size_t pagesize = getpagesize();
mHeapSize = ((size + pagesize - 1) & ~(pagesize - 1));
chunk_t* node = new chunk_t(0, mHeapSize / kMemoryAlign);
mList.push_front(node);
}
SimpleBestFitAllocator::~SimpleBestFitAllocator() {
while (mList.size() != 0) {
chunk_t* removed = mList.front();
mList.pop_front();
#ifdef __clang_analyzer__
// Clang static analyzer gets confused in this loop
// and generates a false positive warning about accessing
// memory that is already freed.
// Add an "assert" to avoid the confusion.
LOG_ALWAYS_FATAL_IF(mList.head() == removed);
#endif
delete removed;
}
}
size_t SimpleBestFitAllocator::size() const {
return mHeapSize;
}
size_t SimpleBestFitAllocator::allocate(size_t size, uint32_t flags) {
Lock lock(mLock);
ssize_t offset = alloc(size, flags);
return offset;
}
status_t SimpleBestFitAllocator::deallocate(size_t offset) {
Lock lock(mLock);
chunk_t const* const freed = dealloc(offset);
if (freed) {
return NO_ERROR;
}
return NAME_NOT_FOUND;
}
ssize_t SimpleBestFitAllocator::alloc(size_t size, uint32_t flags) {
if (size == 0) {
return 0;
}
size = (size + kMemoryAlign - 1) / kMemoryAlign;
size_t pagesize = getpagesize();
Iterator free_chunk_p = mList.end();
for (Iterator p = mList.begin(); p != mList.end(); p++) {
chunk_t* cur = *p;
int extra = 0;
if (flags & PAGE_ALIGNED) extra = (-cur->start & ((pagesize / kMemoryAlign) - 1));
// best fit
if (cur->free && (cur->size >= (size + extra))) {
if ((free_chunk_p == mList.end()) || (cur->size < (*free_chunk_p)->size)) {
free_chunk_p = p;
}
if (cur->size == size) {
break;
}
}
}
if (free_chunk_p != mList.end()) {
chunk_t* free_chunk = *free_chunk_p;
const size_t free_size = free_chunk->size;
free_chunk->free = 0;
free_chunk->size = size;
if (free_size > size) {
int extra = 0;
if (flags & PAGE_ALIGNED)
extra = (-free_chunk->start & ((pagesize / kMemoryAlign) - 1));
if (extra) {
chunk_t* split = new chunk_t(free_chunk->start, extra);
free_chunk->start += extra;
mList.insert(free_chunk_p, split);
}
ALOGE_IF(
(flags & PAGE_ALIGNED) && ((free_chunk->start * kMemoryAlign) & (pagesize - 1)),
"PAGE_ALIGNED requested, but page is not aligned!!!");
const ssize_t tail_free = free_size - (size + extra);
if (tail_free > 0) {
chunk_t* split = new chunk_t(free_chunk->start + free_chunk->size, tail_free);
mList.insert(++free_chunk_p, split);
}
}
return (free_chunk->start) * kMemoryAlign;
}
return NO_MEMORY;
}
SimpleBestFitAllocator::chunk_t* SimpleBestFitAllocator::dealloc(size_t start) {
start = start / kMemoryAlign;
for (Iterator pos = mList.begin(); pos != mList.end(); pos++) {
chunk_t* cur = *pos;
if (cur->start == start) {
LOG_FATAL_IF(cur->free, "block at offset 0x%08lX of size 0x%08lX already freed",
cur->start * kMemoryAlign, cur->size * kMemoryAlign);
// merge freed blocks together
chunk_t* freed = cur;
cur->free = 1;
do {
if (pos != mList.begin()) {
pos--;
chunk_t* const p = *pos;
pos++;
if (p->free || !cur->size) {
freed = p;
p->size += cur->size;
mList.erase(pos);
delete cur;
}
}
if (++pos == mList.end()) break;
cur = *pos;
} while (cur && cur->free);
#ifndef NDEBUG
if (!freed->free) {
dump_l("dealloc (!freed->free)");
}
#endif
LOG_FATAL_IF(!freed->free, "freed block at offset 0x%08lX of size 0x%08lX is not free!",
freed->start * kMemoryAlign, freed->size * kMemoryAlign);
return freed;
}
}
return 0;
}
void SimpleBestFitAllocator::dump(const char* tag) const {
Lock lock(mLock);
dump_l(tag);
}
void SimpleBestFitAllocator::dump_l(const char* tag) const {
string result;
dump_l(result, tag);
ALOGD("%s", result.c_str());
}
void SimpleBestFitAllocator::dump(string& result, const char* tag) const {
Lock lock(mLock);
dump_l(result, tag);
}
void SimpleBestFitAllocator::dump_l(string& result, const char* tag) const {
size_t size = 0;
int32_t i = 0;
const size_t SIZE = 256;
char buffer[SIZE];
snprintf(buffer, SIZE, " %s (%p, size=%u)\n", tag, this, (unsigned int)mHeapSize);
result.append(buffer);
for (IteratorConst pos = mList.begin(); pos != mList.end(); pos++) {
chunk_t const* cur = *pos;
if (!cur->free) size += cur->size * kMemoryAlign;
i++;
}
snprintf(buffer, SIZE, " size allocated: %u (%u KB)\n", int(size), int(size / 1024));
result.append(buffer);
}
bool HidlMemoryDealer::isOk(const MemoryBlock& memblk) {
return memblk.token != nullptr;
}
sp<::android::hidl::memory::V1_0::IMemory> HidlMemoryDealer::heap() {
return mHeap;
}
// The required heap size alignment is 4096 bytes
static const uint64_t kHeapSizeAlignment = (0x1ULL << 12);
sp<HidlMemoryDealer> HidlMemoryDealer::getInstance(const hidl_memory& mem) {
uint64_t msk = (kHeapSizeAlignment - 1);
if (mem.size() & msk || !(mem.size() & ~msk)) {
ALOGE("size is not aligned to %x", static_cast<uint32_t>(kHeapSizeAlignment));
return nullptr;
}
sp<IMemory> heap = mapMemory(mem);
if (heap == nullptr) {
ALOGE("fail to mapMemory");
return nullptr;
}
return new HidlMemoryDealer(heap, mem);
}
HidlMemoryDealer::HidlMemoryDealer(sp<IMemory> heap, const hidl_memory& mem)
: MemoryDealer(heap->getSize()),
mHeap(heap),
mToken(new HidlMemoryToken(HidlMemory::getInstance(mem))) {}
::android::hidl::memory::block::V1_0::MemoryBlock HidlMemoryDealer::allocate(size_t size) {
MemoryBlock memblk = {nullptr, 0xFFFFFFFFULL, 0xFFFFFFFFULL};
ssize_t offset = allocateOffset(size);
if (offset >= 0) {
memblk.token = mToken;
memblk.size = size;
memblk.offset = offset;
}
return memblk;
}
}; // namespace hardware
}; // namespace android