| /* |
| * Copyright (C) 2024 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 "BufferReleaseChannel" |
| |
| #include <fcntl.h> |
| #include <sys/socket.h> |
| #include <sys/uio.h> |
| |
| #include <android-base/result.h> |
| #include <android/binder_status.h> |
| #include <binder/Parcel.h> |
| #include <utils/Flattenable.h> |
| |
| #include <gui/BufferReleaseChannel.h> |
| #include <private/gui/ParcelUtils.h> |
| |
| using android::base::Result; |
| |
| namespace android::gui { |
| |
| namespace { |
| |
| template <typename T> |
| void readAligned(const void*& buffer, size_t& size, T& value) { |
| size -= FlattenableUtils::align<alignof(T)>(buffer); |
| FlattenableUtils::read(buffer, size, value); |
| } |
| |
| template <typename T> |
| void writeAligned(void*& buffer, size_t& size, T value) { |
| size -= FlattenableUtils::align<alignof(T)>(buffer); |
| FlattenableUtils::write(buffer, size, value); |
| } |
| |
| template <typename T> |
| void addAligned(size_t& size, T /* value */) { |
| size = FlattenableUtils::align<sizeof(T)>(size); |
| size += sizeof(T); |
| } |
| |
| template <typename T> |
| inline constexpr uint32_t low32(const T n) { |
| return static_cast<uint32_t>(static_cast<uint64_t>(n)); |
| } |
| |
| template <typename T> |
| inline constexpr uint32_t high32(const T n) { |
| return static_cast<uint32_t>(static_cast<uint64_t>(n) >> 32); |
| } |
| |
| template <typename T> |
| inline constexpr T to64(const uint32_t lo, const uint32_t hi) { |
| return static_cast<T>(static_cast<uint64_t>(hi) << 32 | lo); |
| } |
| |
| } // namespace |
| |
| size_t BufferReleaseChannel::Message::getPodSize() const { |
| size_t size = 0; |
| addAligned(size, low32(releaseCallbackId.bufferId)); |
| addAligned(size, high32(releaseCallbackId.bufferId)); |
| addAligned(size, low32(releaseCallbackId.framenumber)); |
| addAligned(size, high32(releaseCallbackId.framenumber)); |
| addAligned(size, maxAcquiredBufferCount); |
| return size; |
| } |
| |
| size_t BufferReleaseChannel::Message::getFlattenedSize() const { |
| size_t size = releaseFence->getFlattenedSize(); |
| size = FlattenableUtils::align<4>(size); |
| size += getPodSize(); |
| return size; |
| } |
| |
| status_t BufferReleaseChannel::Message::flatten(void*& buffer, size_t& size, int*& fds, |
| size_t& count) const { |
| if (status_t err = releaseFence->flatten(buffer, size, fds, count); err != OK) { |
| return err; |
| } |
| size -= FlattenableUtils::align<4>(buffer); |
| |
| // Check we still have enough space |
| if (size < getPodSize()) { |
| return NO_MEMORY; |
| } |
| |
| writeAligned(buffer, size, low32(releaseCallbackId.bufferId)); |
| writeAligned(buffer, size, high32(releaseCallbackId.bufferId)); |
| writeAligned(buffer, size, low32(releaseCallbackId.framenumber)); |
| writeAligned(buffer, size, high32(releaseCallbackId.framenumber)); |
| writeAligned(buffer, size, maxAcquiredBufferCount); |
| return OK; |
| } |
| |
| status_t BufferReleaseChannel::Message::unflatten(void const*& buffer, size_t& size, |
| int const*& fds, size_t& count) { |
| releaseFence = new Fence(); |
| if (status_t err = releaseFence->unflatten(buffer, size, fds, count); err != OK) { |
| return err; |
| } |
| size -= FlattenableUtils::align<4>(buffer); |
| |
| // Check we still have enough space |
| if (size < getPodSize()) { |
| return OK; |
| } |
| |
| uint32_t bufferIdLo = 0, bufferIdHi = 0; |
| uint32_t frameNumberLo = 0, frameNumberHi = 0; |
| |
| readAligned(buffer, size, bufferIdLo); |
| readAligned(buffer, size, bufferIdHi); |
| releaseCallbackId.bufferId = to64<int64_t>(bufferIdLo, bufferIdHi); |
| readAligned(buffer, size, frameNumberLo); |
| readAligned(buffer, size, frameNumberHi); |
| releaseCallbackId.framenumber = to64<uint64_t>(frameNumberLo, frameNumberHi); |
| readAligned(buffer, size, maxAcquiredBufferCount); |
| |
| return OK; |
| } |
| |
| status_t BufferReleaseChannel::ConsumerEndpoint::readReleaseFence( |
| ReleaseCallbackId& outReleaseCallbackId, sp<Fence>& outReleaseFence, |
| uint32_t& outMaxAcquiredBufferCount) { |
| std::lock_guard lock{mMutex}; |
| Message message; |
| mFlattenedBuffer.resize(message.getFlattenedSize()); |
| std::array<uint8_t, CMSG_SPACE(sizeof(int))> controlMessageBuffer{}; |
| |
| iovec iov{ |
| .iov_base = mFlattenedBuffer.data(), |
| .iov_len = mFlattenedBuffer.size(), |
| }; |
| |
| msghdr msg{}; |
| msg.msg_iov = &iov; |
| msg.msg_iovlen = 1; |
| msg.msg_control = controlMessageBuffer.data(); |
| msg.msg_controllen = controlMessageBuffer.size(); |
| |
| ssize_t result; |
| do { |
| result = recvmsg(mFd, &msg, 0); |
| } while (result == -1 && errno == EINTR); |
| if (result == -1) { |
| if (errno == EWOULDBLOCK || errno == EAGAIN) { |
| return WOULD_BLOCK; |
| } |
| ALOGE("Error reading release fence from socket: error %d (%s)", errno, strerror(errno)); |
| return UNKNOWN_ERROR; |
| } |
| |
| if (msg.msg_iovlen != 1) { |
| ALOGE("Error reading release fence from socket: bad data length"); |
| return UNKNOWN_ERROR; |
| } |
| |
| if (msg.msg_controllen % sizeof(int) != 0) { |
| ALOGE("Error reading release fence from socket: bad fd length"); |
| return UNKNOWN_ERROR; |
| } |
| |
| size_t dataLen = msg.msg_iov->iov_len; |
| const void* data = static_cast<const void*>(msg.msg_iov->iov_base); |
| if (!data) { |
| ALOGE("Error reading release fence from socket: no buffer data"); |
| return UNKNOWN_ERROR; |
| } |
| |
| size_t fdCount = 0; |
| const int* fdData = nullptr; |
| if (cmsghdr* cmsg = CMSG_FIRSTHDR(&msg)) { |
| fdData = reinterpret_cast<const int*>(CMSG_DATA(cmsg)); |
| fdCount = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int); |
| } |
| |
| if (status_t err = message.unflatten(data, dataLen, fdData, fdCount); err != OK) { |
| return err; |
| } |
| |
| outReleaseCallbackId = message.releaseCallbackId; |
| outReleaseFence = std::move(message.releaseFence); |
| outMaxAcquiredBufferCount = message.maxAcquiredBufferCount; |
| |
| return OK; |
| } |
| |
| status_t BufferReleaseChannel::ProducerEndpoint::writeReleaseFence( |
| const ReleaseCallbackId& callbackId, const sp<Fence>& fence, |
| uint32_t maxAcquiredBufferCount) { |
| Message message{callbackId, fence ? fence : Fence::NO_FENCE, maxAcquiredBufferCount}; |
| mFlattenedBuffer.resize(message.getFlattenedSize()); |
| int flattenedFd; |
| { |
| // Make copies of needed items since flatten modifies them, and we don't |
| // want to send anything if there's an error during flatten. |
| void* flattenedBufferPtr = mFlattenedBuffer.data(); |
| size_t flattenedBufferSize = mFlattenedBuffer.size(); |
| int* flattenedFdPtr = &flattenedFd; |
| size_t flattenedFdCount = 1; |
| if (status_t status = message.flatten(flattenedBufferPtr, flattenedBufferSize, |
| flattenedFdPtr, flattenedFdCount); |
| status != OK) { |
| return status; |
| } |
| } |
| |
| iovec iov{}; |
| iov.iov_base = mFlattenedBuffer.data(); |
| iov.iov_len = mFlattenedBuffer.size(); |
| |
| msghdr msg{}; |
| msg.msg_iov = &iov; |
| msg.msg_iovlen = 1; |
| |
| std::array<uint8_t, CMSG_SPACE(sizeof(int))> controlMessageBuffer{}; |
| if (fence && fence->isValid()) { |
| msg.msg_control = controlMessageBuffer.data(); |
| msg.msg_controllen = controlMessageBuffer.size(); |
| |
| cmsghdr* cmsg = CMSG_FIRSTHDR(&msg); |
| cmsg->cmsg_level = SOL_SOCKET; |
| cmsg->cmsg_type = SCM_RIGHTS; |
| cmsg->cmsg_len = CMSG_LEN(sizeof(int)); |
| memcpy(CMSG_DATA(cmsg), &flattenedFd, sizeof(int)); |
| } |
| |
| ssize_t result; |
| do { |
| result = sendmsg(mFd, &msg, 0); |
| } while (result == -1 && errno == EINTR); |
| if (result == -1) { |
| return -errno; |
| } |
| |
| return OK; |
| } |
| |
| status_t BufferReleaseChannel::ProducerEndpoint::readFromParcel(const android::Parcel* parcel) { |
| if (!parcel) return STATUS_BAD_VALUE; |
| SAFE_PARCEL(parcel->readUtf8FromUtf16, &mName); |
| SAFE_PARCEL(parcel->readUniqueFileDescriptor, &mFd); |
| return STATUS_OK; |
| } |
| |
| status_t BufferReleaseChannel::ProducerEndpoint::writeToParcel(android::Parcel* parcel) const { |
| if (!parcel) return STATUS_BAD_VALUE; |
| SAFE_PARCEL(parcel->writeUtf8AsUtf16, mName); |
| SAFE_PARCEL(parcel->writeUniqueFileDescriptor, mFd); |
| return STATUS_OK; |
| } |
| |
| status_t BufferReleaseChannel::open(std::string name, |
| std::unique_ptr<ConsumerEndpoint>& outConsumer, |
| std::shared_ptr<ProducerEndpoint>& outProducer) { |
| outConsumer.reset(); |
| outProducer.reset(); |
| |
| int sockets[2]; |
| if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, sockets)) { |
| ALOGE("[%s] Failed to create socket pair. errorno=%d message='%s'", name.c_str(), errno, |
| strerror(errno)); |
| return -errno; |
| } |
| |
| android::base::unique_fd consumerFd(sockets[0]); |
| android::base::unique_fd producerFd(sockets[1]); |
| |
| // Socket buffer size. The default is typically about 128KB, which is much larger than |
| // we really need. |
| size_t bufferSize = 32 * 1024; |
| if (setsockopt(consumerFd.get(), SOL_SOCKET, SO_SNDBUF, &bufferSize, sizeof(bufferSize)) == |
| -1) { |
| ALOGE("[%s] Failed to set consumer socket send buffer size. errno=%d message='%s'", |
| name.c_str(), errno, strerror(errno)); |
| return -errno; |
| } |
| if (setsockopt(consumerFd.get(), SOL_SOCKET, SO_RCVBUF, &bufferSize, sizeof(bufferSize)) == |
| -1) { |
| ALOGE("[%s] Failed to set consumer socket receive buffer size. errno=%d " |
| "message='%s'", |
| name.c_str(), errno, strerror(errno)); |
| return -errno; |
| } |
| if (setsockopt(producerFd.get(), SOL_SOCKET, SO_SNDBUF, &bufferSize, sizeof(bufferSize)) == |
| -1) { |
| ALOGE("[%s] Failed to set producer socket send buffer size. errno=%d message='%s'", |
| name.c_str(), errno, strerror(errno)); |
| return -errno; |
| } |
| if (setsockopt(producerFd.get(), SOL_SOCKET, SO_RCVBUF, &bufferSize, sizeof(bufferSize)) == |
| -1) { |
| ALOGE("[%s] Failed to set producer socket receive buffer size. errno=%d " |
| "message='%s'", |
| name.c_str(), errno, strerror(errno)); |
| return -errno; |
| } |
| |
| // Configure the consumer socket to be non-blocking. |
| int flags = fcntl(consumerFd.get(), F_GETFL, 0); |
| if (flags == -1) { |
| ALOGE("[%s] Failed to get consumer socket flags. errno=%d message='%s'", name.c_str(), |
| errno, strerror(errno)); |
| return -errno; |
| } |
| if (fcntl(consumerFd.get(), F_SETFL, flags | O_NONBLOCK) == -1) { |
| ALOGE("[%s] Failed to set consumer socket to non-blocking mode. errno=%d " |
| "message='%s'", |
| name.c_str(), errno, strerror(errno)); |
| return -errno; |
| } |
| |
| // Configure a timeout for the producer socket. |
| const timeval timeout{.tv_sec = 1, .tv_usec = 0}; |
| if (setsockopt(producerFd.get(), SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeval)) == -1) { |
| ALOGE("[%s] Failed to set producer socket timeout. errno=%d message='%s'", name.c_str(), |
| errno, strerror(errno)); |
| return -errno; |
| } |
| |
| // Make the consumer read-only |
| if (shutdown(consumerFd.get(), SHUT_WR) == -1) { |
| ALOGE("[%s] Failed to shutdown writing on consumer socket. errno=%d message='%s'", |
| name.c_str(), errno, strerror(errno)); |
| return -errno; |
| } |
| |
| outConsumer = std::make_unique<ConsumerEndpoint>(name, std::move(consumerFd)); |
| outProducer = std::make_shared<ProducerEndpoint>(std::move(name), std::move(producerFd)); |
| return STATUS_OK; |
| } |
| |
| } // namespace android::gui |