You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

444 lines
15 KiB

/*
* Copyright (C) 2020 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_NDEBUG 0
#define LOG_TAG "C2DmaBufAllocator"
#include <BufferAllocator/BufferAllocator.h>
#include <C2Buffer.h>
#include <C2Debug.h>
#include <C2DmaBufAllocator.h>
#include <C2ErrnoUtils.h>
#include <linux/ion.h>
#include <sys/mman.h>
#include <unistd.h> // getpagesize, size_t, close, dup
#include <utils/Log.h>
#include <list>
#include <android-base/properties.h>
#include <media/stagefright/foundation/Mutexed.h>
namespace android {
namespace {
constexpr size_t USAGE_LRU_CACHE_SIZE = 1024;
// max padding after ion/dmabuf allocations in bytes
constexpr uint32_t MAX_PADDING = 0x8000; // 32KB
}
/* =========================== BUFFER HANDLE =========================== */
/**
* Buffer handle
*
* Stores dmabuf fd & metadata
*
* This handle will not capture mapped fd-s as updating that would require a
* global mutex.
*/
struct C2HandleBuf : public C2Handle {
C2HandleBuf(int bufferFd, size_t size)
: C2Handle(cHeader),
mFds{bufferFd},
mInts{int(size & 0xFFFFFFFF), int((uint64_t(size) >> 32) & 0xFFFFFFFF), kMagic} {}
static bool IsValid(const C2Handle* const o);
int bufferFd() const { return mFds.mBuffer; }
size_t size() const {
return size_t(unsigned(mInts.mSizeLo)) | size_t(uint64_t(unsigned(mInts.mSizeHi)) << 32);
}
protected:
struct {
int mBuffer; // dmabuf fd
} mFds;
struct {
int mSizeLo; // low 32-bits of size
int mSizeHi; // high 32-bits of size
int mMagic;
} mInts;
private:
typedef C2HandleBuf _type;
enum {
kMagic = '\xc2io\x00',
numFds = sizeof(mFds) / sizeof(int),
numInts = sizeof(mInts) / sizeof(int),
version = sizeof(C2Handle)
};
// constexpr static C2Handle cHeader = { version, numFds, numInts, {} };
const static C2Handle cHeader;
};
const C2Handle C2HandleBuf::cHeader = {
C2HandleBuf::version, C2HandleBuf::numFds, C2HandleBuf::numInts, {}};
// static
bool C2HandleBuf::IsValid(const C2Handle* const o) {
if (!o || memcmp(o, &cHeader, sizeof(cHeader))) {
return false;
}
const C2HandleBuf* other = static_cast<const C2HandleBuf*>(o);
return other->mInts.mMagic == kMagic;
}
/* =========================== DMABUF ALLOCATION =========================== */
class C2DmaBufAllocation : public C2LinearAllocation {
public:
/* Interface methods */
virtual c2_status_t map(size_t offset, size_t size, C2MemoryUsage usage, C2Fence* fence,
void** addr /* nonnull */) override;
virtual c2_status_t unmap(void* addr, size_t size, C2Fence* fenceFd) override;
virtual ~C2DmaBufAllocation() override;
virtual const C2Handle* handle() const override;
virtual id_t getAllocatorId() const override;
virtual bool equals(const std::shared_ptr<C2LinearAllocation>& other) const override;
// internal methods
/**
* Constructs an allocation via a new allocation.
*
* @param alloc allocator
* @param allocSize size used for the allocator
* @param capacity capacity advertised to the client
* @param heap_name name of the dmabuf heap (device)
* @param flags flags
* @param id allocator id
*/
C2DmaBufAllocation(BufferAllocator& alloc, size_t allocSize, size_t capacity,
C2String heap_name, unsigned flags, C2Allocator::id_t id);
/**
* Constructs an allocation by wrapping an existing allocation.
*
* @param size capacity advertised to the client
* @param shareFd dmabuf fd of the wrapped allocation
* @param id allocator id
*/
C2DmaBufAllocation(size_t size, int shareFd, C2Allocator::id_t id);
c2_status_t status() const;
protected:
virtual c2_status_t mapInternal(size_t mapSize, size_t mapOffset, size_t alignmentBytes,
int prot, int flags, void** base, void** addr) {
c2_status_t err = C2_OK;
*base = mmap(nullptr, mapSize, prot, flags, mHandle.bufferFd(), mapOffset);
ALOGV("mmap(size = %zu, prot = %d, flags = %d, mapFd = %d, offset = %zu) "
"returned (%d)",
mapSize, prot, flags, mHandle.bufferFd(), mapOffset, errno);
if (*base == MAP_FAILED) {
*base = *addr = nullptr;
err = c2_map_errno<EINVAL>(errno);
} else {
*addr = (uint8_t*)*base + alignmentBytes;
}
return err;
}
C2Allocator::id_t mId;
C2HandleBuf mHandle;
c2_status_t mInit;
struct Mapping {
void* addr;
size_t alignmentBytes;
size_t size;
};
Mutexed<std::list<Mapping>> mMappings;
// TODO: we could make this encapsulate shared_ptr and copiable
C2_DO_NOT_COPY(C2DmaBufAllocation);
};
c2_status_t C2DmaBufAllocation::map(size_t offset, size_t size, C2MemoryUsage usage, C2Fence* fence,
void** addr) {
(void)fence; // TODO: wait for fence
*addr = nullptr;
if (!mMappings.lock()->empty()) {
ALOGV("multiple map");
// TODO: technically we should return DUPLICATE here, but our block views
// don't actually unmap, so we end up remapping the buffer multiple times.
//
// return C2_DUPLICATE;
}
if (size == 0) {
return C2_BAD_VALUE;
}
int prot = PROT_NONE;
int flags = MAP_SHARED;
if (usage.expected & C2MemoryUsage::CPU_READ) {
prot |= PROT_READ;
}
if (usage.expected & C2MemoryUsage::CPU_WRITE) {
prot |= PROT_WRITE;
}
size_t alignmentBytes = offset % PAGE_SIZE;
size_t mapOffset = offset - alignmentBytes;
size_t mapSize = size + alignmentBytes;
Mapping map = {nullptr, alignmentBytes, mapSize};
c2_status_t err =
mapInternal(mapSize, mapOffset, alignmentBytes, prot, flags, &(map.addr), addr);
if (map.addr) {
mMappings.lock()->push_back(map);
}
return err;
}
c2_status_t C2DmaBufAllocation::unmap(void* addr, size_t size, C2Fence* fence) {
Mutexed<std::list<Mapping>>::Locked mappings(mMappings);
if (mappings->empty()) {
ALOGD("tried to unmap unmapped buffer");
return C2_NOT_FOUND;
}
for (auto it = mappings->begin(); it != mappings->end(); ++it) {
if (addr != (uint8_t*)it->addr + it->alignmentBytes ||
size + it->alignmentBytes != it->size) {
continue;
}
int err = munmap(it->addr, it->size);
if (err != 0) {
ALOGD("munmap failed");
return c2_map_errno<EINVAL>(errno);
}
if (fence) {
*fence = C2Fence(); // not using fences
}
(void)mappings->erase(it);
ALOGV("successfully unmapped: %d", mHandle.bufferFd());
return C2_OK;
}
ALOGD("unmap failed to find specified map");
return C2_BAD_VALUE;
}
c2_status_t C2DmaBufAllocation::status() const {
return mInit;
}
C2Allocator::id_t C2DmaBufAllocation::getAllocatorId() const {
return mId;
}
bool C2DmaBufAllocation::equals(const std::shared_ptr<C2LinearAllocation>& other) const {
if (!other || other->getAllocatorId() != getAllocatorId()) {
return false;
}
// get user handle to compare objects
std::shared_ptr<C2DmaBufAllocation> otherAsBuf =
std::static_pointer_cast<C2DmaBufAllocation>(other);
return mHandle.bufferFd() == otherAsBuf->mHandle.bufferFd();
}
const C2Handle* C2DmaBufAllocation::handle() const {
return &mHandle;
}
C2DmaBufAllocation::~C2DmaBufAllocation() {
Mutexed<std::list<Mapping>>::Locked mappings(mMappings);
if (!mappings->empty()) {
ALOGD("Dangling mappings!");
for (const Mapping& map : *mappings) {
int err = munmap(map.addr, map.size);
if (err) ALOGD("munmap failed");
}
}
if (mInit == C2_OK) {
native_handle_close(&mHandle);
}
}
C2DmaBufAllocation::C2DmaBufAllocation(BufferAllocator& alloc, size_t allocSize, size_t capacity,
C2String heap_name, unsigned flags, C2Allocator::id_t id)
: C2LinearAllocation(capacity), mHandle(-1, 0) {
int bufferFd = -1;
int ret = 0;
bufferFd = alloc.Alloc(heap_name, allocSize, flags);
if (bufferFd < 0) {
ret = bufferFd;
}
// this may be a non-working handle if bufferFd is negative
mHandle = C2HandleBuf(bufferFd, capacity);
mId = id;
mInit = c2_status_t(c2_map_errno<ENOMEM, EACCES, EINVAL>(ret));
}
C2DmaBufAllocation::C2DmaBufAllocation(size_t size, int shareFd, C2Allocator::id_t id)
: C2LinearAllocation(size), mHandle(-1, 0) {
mHandle = C2HandleBuf(shareFd, size);
mId = id;
mInit = c2_status_t(c2_map_errno<ENOMEM, EACCES, EINVAL>(0));
}
/* =========================== DMABUF ALLOCATOR =========================== */
C2DmaBufAllocator::C2DmaBufAllocator(id_t id) : mInit(C2_OK) {
C2MemoryUsage minUsage = {0, 0};
C2MemoryUsage maxUsage = {C2MemoryUsage::CPU_READ, C2MemoryUsage::CPU_WRITE};
Traits traits = {"android.allocator.dmabuf", id, LINEAR, minUsage, maxUsage};
mTraits = std::make_shared<Traits>(traits);
}
C2Allocator::id_t C2DmaBufAllocator::getId() const {
std::lock_guard<std::mutex> lock(mUsageMapperLock);
return mTraits->id;
}
C2String C2DmaBufAllocator::getName() const {
std::lock_guard<std::mutex> lock(mUsageMapperLock);
return mTraits->name;
}
std::shared_ptr<const C2Allocator::Traits> C2DmaBufAllocator::getTraits() const {
std::lock_guard<std::mutex> lock(mUsageMapperLock);
return mTraits;
}
void C2DmaBufAllocator::setUsageMapper(const UsageMapperFn& mapper __unused, uint64_t minUsage,
uint64_t maxUsage, uint64_t blockSize) {
std::lock_guard<std::mutex> lock(mUsageMapperLock);
mUsageMapperCache.clear();
mUsageMapperLru.clear();
mUsageMapper = mapper;
Traits traits = {mTraits->name, mTraits->id, LINEAR, C2MemoryUsage(minUsage),
C2MemoryUsage(maxUsage)};
mTraits = std::make_shared<Traits>(traits);
mBlockSize = blockSize;
}
std::size_t C2DmaBufAllocator::MapperKeyHash::operator()(const MapperKey& k) const {
return std::hash<uint64_t>{}(k.first) ^ std::hash<size_t>{}(k.second);
}
c2_status_t C2DmaBufAllocator::mapUsage(C2MemoryUsage usage, size_t capacity, C2String* heap_name,
unsigned* flags) {
std::lock_guard<std::mutex> lock(mUsageMapperLock);
c2_status_t res = C2_OK;
// align capacity
capacity = (capacity + mBlockSize - 1) & ~(mBlockSize - 1);
MapperKey key = std::make_pair(usage.expected, capacity);
auto entry = mUsageMapperCache.find(key);
if (entry == mUsageMapperCache.end()) {
if (mUsageMapper) {
res = mUsageMapper(usage, capacity, heap_name, flags);
} else {
if (C2DmaBufAllocator::system_uncached_supported() &&
!(usage.expected & (C2MemoryUsage::CPU_READ | C2MemoryUsage::CPU_WRITE)))
*heap_name = "system-uncached";
else
*heap_name = "system";
*flags = 0;
res = C2_NO_INIT;
}
// add usage to cache
MapperValue value = std::make_tuple(*heap_name, *flags, res);
mUsageMapperLru.emplace_front(key, value);
mUsageMapperCache.emplace(std::make_pair(key, mUsageMapperLru.begin()));
if (mUsageMapperCache.size() > USAGE_LRU_CACHE_SIZE) {
// remove LRU entry
MapperKey lruKey = mUsageMapperLru.front().first;
mUsageMapperCache.erase(lruKey);
mUsageMapperLru.pop_back();
}
} else {
// move entry to MRU
mUsageMapperLru.splice(mUsageMapperLru.begin(), mUsageMapperLru, entry->second);
const MapperValue& value = entry->second->second;
std::tie(*heap_name, *flags, res) = value;
}
return res;
}
c2_status_t C2DmaBufAllocator::newLinearAllocation(
uint32_t capacity, C2MemoryUsage usage, std::shared_ptr<C2LinearAllocation>* allocation) {
if (allocation == nullptr) {
return C2_BAD_VALUE;
}
allocation->reset();
if (mInit != C2_OK) {
return mInit;
}
C2String heap_name;
unsigned flags = 0;
c2_status_t ret = mapUsage(usage, capacity, &heap_name, &flags);
if (ret && ret != C2_NO_INIT) {
return ret;
}
// TODO: should we pad before mapping usage?
// NOTE: read this property directly from the property as this code has to run on
// Android Q, but the sysprop was only introduced in Android S.
static size_t sPadding =
base::GetUintProperty("media.c2.dmabuf.padding", (uint32_t)0, MAX_PADDING);
if (sPadding > SIZE_MAX - capacity) {
// size would overflow
ALOGD("dmabuf_alloc: size #%x cannot accommodate padding #%zx", capacity, sPadding);
return C2_NO_MEMORY;
}
size_t allocSize = (size_t)capacity + sPadding;
// TODO: should we align allocation size to mBlockSize to reflect the true allocation size?
std::shared_ptr<C2DmaBufAllocation> alloc = std::make_shared<C2DmaBufAllocation>(
mBufferAllocator, allocSize, allocSize - sPadding, heap_name, flags, getId());
ret = alloc->status();
if (ret == C2_OK) {
*allocation = alloc;
}
return ret;
}
c2_status_t C2DmaBufAllocator::priorLinearAllocation(
const C2Handle* handle, std::shared_ptr<C2LinearAllocation>* allocation) {
*allocation = nullptr;
if (mInit != C2_OK) {
return mInit;
}
if (!C2HandleBuf::IsValid(handle)) {
return C2_BAD_VALUE;
}
// TODO: get capacity and validate it
const C2HandleBuf* h = static_cast<const C2HandleBuf*>(handle);
std::shared_ptr<C2DmaBufAllocation> alloc =
std::make_shared<C2DmaBufAllocation>(h->size(), h->bufferFd(), getId());
c2_status_t ret = alloc->status();
if (ret == C2_OK) {
*allocation = alloc;
native_handle_delete(
const_cast<native_handle_t*>(reinterpret_cast<const native_handle_t*>(handle)));
}
return ret;
}
// static
bool C2DmaBufAllocator::CheckHandle(const C2Handle* const o) {
return C2HandleBuf::IsValid(o);
}
} // namespace android