| /* |
| * Copyright (C) 2018 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 TRACE_TAG USB |
| |
| #include "sysdeps.h" |
| |
| #include <errno.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/ioctl.h> |
| #include <sys/types.h> |
| #include <unistd.h> |
| |
| #include <linux/usb/functionfs.h> |
| #include <sys/eventfd.h> |
| |
| #include <algorithm> |
| #include <array> |
| #include <future> |
| #include <memory> |
| #include <mutex> |
| #include <optional> |
| #include <vector> |
| |
| #include <asyncio/AsyncIO.h> |
| |
| #include <android-base/logging.h> |
| #include <android-base/macros.h> |
| #include <android-base/properties.h> |
| #include <android-base/thread_annotations.h> |
| |
| #include <adbd/usb.h> |
| |
| #include "adb_unique_fd.h" |
| #include "adb_utils.h" |
| #include "sysdeps/chrono.h" |
| #include "transport.h" |
| #include "types.h" |
| |
| using android::base::StringPrintf; |
| |
| // We can't find out whether we have support for AIO on ffs endpoints until we submit a read. |
| static std::optional<bool> gFfsAioSupported; |
| |
| // Not all USB controllers support operations larger than 16k, so don't go above that. |
| static constexpr size_t kUsbReadQueueDepth = 32; |
| static constexpr size_t kUsbReadSize = 4 * PAGE_SIZE; |
| |
| static constexpr size_t kUsbWriteQueueDepth = 32; |
| static constexpr size_t kUsbWriteSize = 4 * PAGE_SIZE; |
| |
| static const char* to_string(enum usb_functionfs_event_type type) { |
| switch (type) { |
| case FUNCTIONFS_BIND: |
| return "FUNCTIONFS_BIND"; |
| case FUNCTIONFS_UNBIND: |
| return "FUNCTIONFS_UNBIND"; |
| case FUNCTIONFS_ENABLE: |
| return "FUNCTIONFS_ENABLE"; |
| case FUNCTIONFS_DISABLE: |
| return "FUNCTIONFS_DISABLE"; |
| case FUNCTIONFS_SETUP: |
| return "FUNCTIONFS_SETUP"; |
| case FUNCTIONFS_SUSPEND: |
| return "FUNCTIONFS_SUSPEND"; |
| case FUNCTIONFS_RESUME: |
| return "FUNCTIONFS_RESUME"; |
| } |
| } |
| |
| enum class TransferDirection : uint64_t { |
| READ = 0, |
| WRITE = 1, |
| }; |
| |
| struct TransferId { |
| TransferDirection direction : 1; |
| uint64_t id : 63; |
| |
| TransferId() : TransferId(TransferDirection::READ, 0) {} |
| |
| private: |
| TransferId(TransferDirection direction, uint64_t id) : direction(direction), id(id) {} |
| |
| public: |
| explicit operator uint64_t() const { |
| uint64_t result; |
| static_assert(sizeof(*this) == sizeof(result)); |
| memcpy(&result, this, sizeof(*this)); |
| return result; |
| } |
| |
| static TransferId read(uint64_t id) { return TransferId(TransferDirection::READ, id); } |
| static TransferId write(uint64_t id) { return TransferId(TransferDirection::WRITE, id); } |
| |
| static TransferId from_value(uint64_t value) { |
| TransferId result; |
| memcpy(&result, &value, sizeof(value)); |
| return result; |
| } |
| }; |
| |
| struct IoBlock { |
| bool pending = false; |
| struct iocb control; |
| std::shared_ptr<Block> payload; |
| |
| TransferId id() const { return TransferId::from_value(control.aio_data); } |
| }; |
| |
| struct ScopedAioContext { |
| ScopedAioContext() = default; |
| ~ScopedAioContext() { reset(); } |
| |
| ScopedAioContext(ScopedAioContext&& move) { reset(move.release()); } |
| ScopedAioContext(const ScopedAioContext& copy) = delete; |
| |
| ScopedAioContext& operator=(ScopedAioContext&& move) { |
| reset(move.release()); |
| return *this; |
| } |
| ScopedAioContext& operator=(const ScopedAioContext& copy) = delete; |
| |
| static ScopedAioContext Create(size_t max_events) { |
| aio_context_t ctx = 0; |
| if (io_setup(max_events, &ctx) != 0) { |
| PLOG(FATAL) << "failed to create aio_context_t"; |
| } |
| ScopedAioContext result; |
| result.reset(ctx); |
| return result; |
| } |
| |
| aio_context_t release() { |
| aio_context_t result = context_; |
| context_ = 0; |
| return result; |
| } |
| |
| void reset(aio_context_t new_context = 0) { |
| if (context_ != 0) { |
| io_destroy(context_); |
| } |
| |
| context_ = new_context; |
| } |
| |
| aio_context_t get() { return context_; } |
| |
| private: |
| aio_context_t context_ = 0; |
| }; |
| |
| struct UsbFfsConnection : public Connection { |
| UsbFfsConnection(unique_fd control, unique_fd read, unique_fd write, |
| std::promise<void> destruction_notifier) |
| : worker_started_(false), |
| stopped_(false), |
| destruction_notifier_(std::move(destruction_notifier)), |
| control_fd_(std::move(control)), |
| read_fd_(std::move(read)), |
| write_fd_(std::move(write)) { |
| LOG(INFO) << "UsbFfsConnection constructed"; |
| worker_event_fd_.reset(eventfd(0, EFD_CLOEXEC)); |
| if (worker_event_fd_ == -1) { |
| PLOG(FATAL) << "failed to create eventfd"; |
| } |
| |
| monitor_event_fd_.reset(eventfd(0, EFD_CLOEXEC)); |
| if (monitor_event_fd_ == -1) { |
| PLOG(FATAL) << "failed to create eventfd"; |
| } |
| |
| aio_context_ = ScopedAioContext::Create(kUsbReadQueueDepth + kUsbWriteQueueDepth); |
| } |
| |
| ~UsbFfsConnection() { |
| LOG(INFO) << "UsbFfsConnection being destroyed"; |
| Stop(); |
| monitor_thread_.join(); |
| |
| // We need to explicitly close our file descriptors before we notify our destruction, |
| // because the thread listening on the future will immediately try to reopen the endpoint. |
| aio_context_.reset(); |
| control_fd_.reset(); |
| read_fd_.reset(); |
| write_fd_.reset(); |
| |
| destruction_notifier_.set_value(); |
| } |
| |
| virtual bool Write(std::unique_ptr<apacket> packet) override final { |
| LOG(DEBUG) << "USB write: " << dump_header(&packet->msg); |
| Block header(sizeof(packet->msg)); |
| memcpy(header.data(), &packet->msg, sizeof(packet->msg)); |
| |
| std::lock_guard<std::mutex> lock(write_mutex_); |
| write_requests_.push_back(CreateWriteBlock(std::move(header), next_write_id_++)); |
| if (!packet->payload.empty()) { |
| // The kernel attempts to allocate a contiguous block of memory for each write, |
| // which can fail if the write is large and the kernel heap is fragmented. |
| // Split large writes into smaller chunks to avoid this. |
| std::shared_ptr<Block> payload = std::make_shared<Block>(std::move(packet->payload)); |
| size_t offset = 0; |
| size_t len = payload->size(); |
| |
| while (len > 0) { |
| size_t write_size = std::min(kUsbWriteSize, len); |
| write_requests_.push_back( |
| CreateWriteBlock(payload, offset, write_size, next_write_id_++)); |
| len -= write_size; |
| offset += write_size; |
| } |
| } |
| SubmitWrites(); |
| return true; |
| } |
| |
| virtual void Start() override final { StartMonitor(); } |
| |
| virtual void Stop() override final { |
| if (stopped_.exchange(true)) { |
| return; |
| } |
| stopped_ = true; |
| uint64_t notify = 1; |
| ssize_t rc = adb_write(worker_event_fd_.get(), ¬ify, sizeof(notify)); |
| if (rc < 0) { |
| PLOG(FATAL) << "failed to notify worker eventfd to stop UsbFfsConnection"; |
| } |
| CHECK_EQ(static_cast<size_t>(rc), sizeof(notify)); |
| |
| rc = adb_write(monitor_event_fd_.get(), ¬ify, sizeof(notify)); |
| if (rc < 0) { |
| PLOG(FATAL) << "failed to notify monitor eventfd to stop UsbFfsConnection"; |
| } |
| |
| CHECK_EQ(static_cast<size_t>(rc), sizeof(notify)); |
| } |
| |
| private: |
| void StartMonitor() { |
| // This is a bit of a mess. |
| // It's possible for io_submit to end up blocking, if we call it as the endpoint |
| // becomes disabled. Work around this by having a monitor thread to listen for functionfs |
| // lifecycle events. If we notice an error condition (either we've become disabled, or we |
| // were never enabled in the first place), we send interruption signals to the worker thread |
| // until it dies, and then report failure to the transport via HandleError, which will |
| // eventually result in the transport being destroyed, which will result in UsbFfsConnection |
| // being destroyed, which unblocks the open thread and restarts this entire process. |
| static std::once_flag handler_once; |
| std::call_once(handler_once, []() { signal(kInterruptionSignal, [](int) {}); }); |
| |
| monitor_thread_ = std::thread([this]() { |
| adb_thread_setname("UsbFfs-monitor"); |
| |
| bool bound = false; |
| bool enabled = false; |
| bool running = true; |
| while (running) { |
| adb_pollfd pfd[2] = { |
| { .fd = control_fd_.get(), .events = POLLIN, .revents = 0 }, |
| { .fd = monitor_event_fd_.get(), .events = POLLIN, .revents = 0 }, |
| }; |
| |
| // If we don't see our first bind within a second, try again. |
| int timeout_ms = bound ? -1 : 1000; |
| |
| int rc = TEMP_FAILURE_RETRY(adb_poll(pfd, 2, timeout_ms)); |
| if (rc == -1) { |
| PLOG(FATAL) << "poll on USB control fd failed"; |
| } else if (rc == 0) { |
| LOG(WARNING) << "timed out while waiting for FUNCTIONFS_BIND, trying again"; |
| break; |
| } |
| |
| if (pfd[1].revents) { |
| // We were told to die. |
| break; |
| } |
| |
| struct usb_functionfs_event event; |
| if (TEMP_FAILURE_RETRY(adb_read(control_fd_.get(), &event, sizeof(event))) != |
| sizeof(event)) { |
| PLOG(FATAL) << "failed to read functionfs event"; |
| } |
| |
| LOG(INFO) << "USB event: " |
| << to_string(static_cast<usb_functionfs_event_type>(event.type)); |
| |
| switch (event.type) { |
| case FUNCTIONFS_BIND: |
| if (bound) { |
| LOG(WARNING) << "received FUNCTIONFS_BIND while already bound?"; |
| running = false; |
| } |
| |
| if (enabled) { |
| LOG(WARNING) << "received FUNCTIONFS_BIND while already enabled?"; |
| running = false; |
| } |
| |
| bound = true; |
| break; |
| |
| case FUNCTIONFS_ENABLE: |
| if (!bound) { |
| LOG(WARNING) << "received FUNCTIONFS_ENABLE while not bound?"; |
| running = false; |
| } |
| |
| if (enabled) { |
| LOG(WARNING) << "received FUNCTIONFS_ENABLE while already enabled?"; |
| running = false; |
| } |
| |
| enabled = true; |
| StartWorker(); |
| break; |
| |
| case FUNCTIONFS_DISABLE: |
| if (!bound) { |
| LOG(WARNING) << "received FUNCTIONFS_DISABLE while not bound?"; |
| } |
| |
| if (!enabled) { |
| LOG(WARNING) << "received FUNCTIONFS_DISABLE while not enabled?"; |
| } |
| |
| enabled = false; |
| running = false; |
| break; |
| |
| case FUNCTIONFS_UNBIND: |
| if (enabled) { |
| LOG(WARNING) << "received FUNCTIONFS_UNBIND while still enabled?"; |
| } |
| |
| if (!bound) { |
| LOG(WARNING) << "received FUNCTIONFS_UNBIND when not bound?"; |
| } |
| |
| bound = false; |
| running = false; |
| break; |
| } |
| } |
| |
| StopWorker(); |
| HandleError("monitor thread finished"); |
| }); |
| } |
| |
| void StartWorker() { |
| CHECK(!worker_started_); |
| worker_started_ = true; |
| worker_thread_ = std::thread([this]() { |
| adb_thread_setname("UsbFfs-worker"); |
| for (size_t i = 0; i < kUsbReadQueueDepth; ++i) { |
| read_requests_[i] = CreateReadBlock(next_read_id_++); |
| if (!SubmitRead(&read_requests_[i])) { |
| return; |
| } |
| } |
| |
| while (!stopped_) { |
| uint64_t dummy; |
| ssize_t rc = adb_read(worker_event_fd_.get(), &dummy, sizeof(dummy)); |
| if (rc == -1) { |
| PLOG(FATAL) << "failed to read from eventfd"; |
| } else if (rc == 0) { |
| LOG(FATAL) << "hit EOF on eventfd"; |
| } |
| |
| ReadEvents(); |
| } |
| }); |
| } |
| |
| void StopWorker() { |
| if (!worker_started_) { |
| return; |
| } |
| |
| pthread_t worker_thread_handle = worker_thread_.native_handle(); |
| while (true) { |
| int rc = pthread_kill(worker_thread_handle, kInterruptionSignal); |
| if (rc != 0) { |
| LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc); |
| break; |
| } |
| |
| std::this_thread::sleep_for(100ms); |
| |
| rc = pthread_kill(worker_thread_handle, 0); |
| if (rc == 0) { |
| continue; |
| } else if (rc == ESRCH) { |
| break; |
| } else { |
| LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc); |
| } |
| } |
| |
| worker_thread_.join(); |
| } |
| |
| void PrepareReadBlock(IoBlock* block, uint64_t id) { |
| block->pending = false; |
| block->payload = std::make_shared<Block>(kUsbReadSize); |
| block->control.aio_data = static_cast<uint64_t>(TransferId::read(id)); |
| block->control.aio_buf = reinterpret_cast<uintptr_t>(block->payload->data()); |
| block->control.aio_nbytes = block->payload->size(); |
| } |
| |
| IoBlock CreateReadBlock(uint64_t id) { |
| IoBlock block; |
| PrepareReadBlock(&block, id); |
| block.control.aio_rw_flags = 0; |
| block.control.aio_lio_opcode = IOCB_CMD_PREAD; |
| block.control.aio_reqprio = 0; |
| block.control.aio_fildes = read_fd_.get(); |
| block.control.aio_offset = 0; |
| block.control.aio_flags = IOCB_FLAG_RESFD; |
| block.control.aio_resfd = worker_event_fd_.get(); |
| return block; |
| } |
| |
| void ReadEvents() { |
| static constexpr size_t kMaxEvents = kUsbReadQueueDepth + kUsbWriteQueueDepth; |
| struct io_event events[kMaxEvents]; |
| struct timespec timeout = {.tv_sec = 0, .tv_nsec = 0}; |
| int rc = io_getevents(aio_context_.get(), 0, kMaxEvents, events, &timeout); |
| if (rc == -1) { |
| HandleError(StringPrintf("io_getevents failed while reading: %s", strerror(errno))); |
| return; |
| } |
| |
| for (int event_idx = 0; event_idx < rc; ++event_idx) { |
| auto& event = events[event_idx]; |
| TransferId id = TransferId::from_value(event.data); |
| |
| if (event.res < 0) { |
| std::string error = |
| StringPrintf("%s %" PRIu64 " failed with error %s", |
| id.direction == TransferDirection::READ ? "read" : "write", |
| id.id, strerror(-event.res)); |
| HandleError(error); |
| return; |
| } |
| |
| if (id.direction == TransferDirection::READ) { |
| HandleRead(id, event.res); |
| } else { |
| HandleWrite(id); |
| } |
| } |
| } |
| |
| void HandleRead(TransferId id, int64_t size) { |
| uint64_t read_idx = id.id % kUsbReadQueueDepth; |
| IoBlock* block = &read_requests_[read_idx]; |
| block->pending = false; |
| block->payload->resize(size); |
| |
| // Notification for completed reads can be received out of order. |
| if (block->id().id != needed_read_id_) { |
| LOG(VERBOSE) << "read " << block->id().id << " completed while waiting for " |
| << needed_read_id_; |
| return; |
| } |
| |
| for (uint64_t id = needed_read_id_;; ++id) { |
| size_t read_idx = id % kUsbReadQueueDepth; |
| IoBlock* current_block = &read_requests_[read_idx]; |
| if (current_block->pending) { |
| break; |
| } |
| ProcessRead(current_block); |
| ++needed_read_id_; |
| } |
| } |
| |
| void ProcessRead(IoBlock* block) { |
| if (!block->payload->empty()) { |
| if (!incoming_header_.has_value()) { |
| CHECK_EQ(sizeof(amessage), block->payload->size()); |
| amessage msg; |
| memcpy(&msg, block->payload->data(), sizeof(amessage)); |
| LOG(DEBUG) << "USB read:" << dump_header(&msg); |
| incoming_header_ = msg; |
| } else { |
| size_t bytes_left = incoming_header_->data_length - incoming_payload_.size(); |
| Block payload = std::move(*block->payload); |
| CHECK_LE(payload.size(), bytes_left); |
| incoming_payload_.append(std::make_unique<Block>(std::move(payload))); |
| } |
| |
| if (incoming_header_->data_length == incoming_payload_.size()) { |
| auto packet = std::make_unique<apacket>(); |
| packet->msg = *incoming_header_; |
| |
| // TODO: Make apacket contain an IOVector so we don't have to coalesce. |
| packet->payload = incoming_payload_.coalesce(); |
| read_callback_(this, std::move(packet)); |
| |
| incoming_header_.reset(); |
| incoming_payload_.clear(); |
| } |
| } |
| |
| PrepareReadBlock(block, block->id().id + kUsbReadQueueDepth); |
| SubmitRead(block); |
| } |
| |
| bool SubmitRead(IoBlock* block) { |
| block->pending = true; |
| struct iocb* iocb = &block->control; |
| if (io_submit(aio_context_.get(), 1, &iocb) != 1) { |
| if (errno == EINVAL && !gFfsAioSupported.has_value()) { |
| HandleError("failed to submit first read, AIO on FFS not supported"); |
| gFfsAioSupported = false; |
| return false; |
| } |
| |
| HandleError(StringPrintf("failed to submit read: %s", strerror(errno))); |
| return false; |
| } |
| |
| gFfsAioSupported = true; |
| return true; |
| } |
| |
| void HandleWrite(TransferId id) { |
| std::lock_guard<std::mutex> lock(write_mutex_); |
| auto it = |
| std::find_if(write_requests_.begin(), write_requests_.end(), [id](const auto& req) { |
| return static_cast<uint64_t>(req->id()) == static_cast<uint64_t>(id); |
| }); |
| CHECK(it != write_requests_.end()); |
| |
| write_requests_.erase(it); |
| size_t outstanding_writes = --writes_submitted_; |
| LOG(DEBUG) << "USB write: reaped, down to " << outstanding_writes; |
| |
| SubmitWrites(); |
| } |
| |
| std::unique_ptr<IoBlock> CreateWriteBlock(std::shared_ptr<Block> payload, size_t offset, |
| size_t len, uint64_t id) { |
| auto block = std::make_unique<IoBlock>(); |
| block->payload = std::move(payload); |
| block->control.aio_data = static_cast<uint64_t>(TransferId::write(id)); |
| block->control.aio_rw_flags = 0; |
| block->control.aio_lio_opcode = IOCB_CMD_PWRITE; |
| block->control.aio_reqprio = 0; |
| block->control.aio_fildes = write_fd_.get(); |
| block->control.aio_buf = reinterpret_cast<uintptr_t>(block->payload->data() + offset); |
| block->control.aio_nbytes = len; |
| block->control.aio_offset = 0; |
| block->control.aio_flags = IOCB_FLAG_RESFD; |
| block->control.aio_resfd = worker_event_fd_.get(); |
| return block; |
| } |
| |
| std::unique_ptr<IoBlock> CreateWriteBlock(Block payload, uint64_t id) { |
| std::shared_ptr<Block> block = std::make_shared<Block>(std::move(payload)); |
| size_t len = block->size(); |
| return CreateWriteBlock(std::move(block), 0, len, id); |
| } |
| |
| void SubmitWrites() REQUIRES(write_mutex_) { |
| if (writes_submitted_ == kUsbWriteQueueDepth) { |
| return; |
| } |
| |
| ssize_t writes_to_submit = std::min(kUsbWriteQueueDepth - writes_submitted_, |
| write_requests_.size() - writes_submitted_); |
| CHECK_GE(writes_to_submit, 0); |
| if (writes_to_submit == 0) { |
| return; |
| } |
| |
| struct iocb* iocbs[kUsbWriteQueueDepth]; |
| for (int i = 0; i < writes_to_submit; ++i) { |
| CHECK(!write_requests_[writes_submitted_ + i]->pending); |
| write_requests_[writes_submitted_ + i]->pending = true; |
| iocbs[i] = &write_requests_[writes_submitted_ + i]->control; |
| LOG(VERBOSE) << "submitting write_request " << static_cast<void*>(iocbs[i]); |
| } |
| |
| writes_submitted_ += writes_to_submit; |
| |
| int rc = io_submit(aio_context_.get(), writes_to_submit, iocbs); |
| if (rc == -1) { |
| HandleError(StringPrintf("failed to submit write requests: %s", strerror(errno))); |
| return; |
| } else if (rc != writes_to_submit) { |
| LOG(FATAL) << "failed to submit all writes: wanted to submit " << writes_to_submit |
| << ", actually submitted " << rc; |
| } |
| } |
| |
| void HandleError(const std::string& error) { |
| std::call_once(error_flag_, [&]() { |
| error_callback_(this, error); |
| if (!stopped_) { |
| Stop(); |
| } |
| }); |
| } |
| |
| std::thread monitor_thread_; |
| |
| bool worker_started_; |
| std::thread worker_thread_; |
| |
| std::atomic<bool> stopped_; |
| std::promise<void> destruction_notifier_; |
| std::once_flag error_flag_; |
| |
| unique_fd worker_event_fd_; |
| unique_fd monitor_event_fd_; |
| |
| ScopedAioContext aio_context_; |
| unique_fd control_fd_; |
| unique_fd read_fd_; |
| unique_fd write_fd_; |
| |
| std::optional<amessage> incoming_header_; |
| IOVector incoming_payload_; |
| |
| std::array<IoBlock, kUsbReadQueueDepth> read_requests_; |
| IOVector read_data_; |
| |
| // ID of the next request that we're going to send out. |
| size_t next_read_id_ = 0; |
| |
| // ID of the next packet we're waiting for. |
| size_t needed_read_id_ = 0; |
| |
| std::mutex write_mutex_; |
| std::deque<std::unique_ptr<IoBlock>> write_requests_ GUARDED_BY(write_mutex_); |
| size_t next_write_id_ GUARDED_BY(write_mutex_) = 0; |
| size_t writes_submitted_ GUARDED_BY(write_mutex_) = 0; |
| |
| static constexpr int kInterruptionSignal = SIGUSR1; |
| }; |
| |
| void usb_init_legacy(); |
| |
| static void usb_ffs_open_thread() { |
| adb_thread_setname("usb ffs open"); |
| |
| while (true) { |
| if (gFfsAioSupported.has_value() && !gFfsAioSupported.value()) { |
| LOG(INFO) << "failed to use nonblocking ffs, falling back to legacy"; |
| return usb_init_legacy(); |
| } |
| |
| unique_fd control; |
| unique_fd bulk_out; |
| unique_fd bulk_in; |
| if (!open_functionfs(&control, &bulk_out, &bulk_in)) { |
| std::this_thread::sleep_for(1s); |
| continue; |
| } |
| |
| atransport* transport = new atransport(); |
| transport->serial = "UsbFfs"; |
| std::promise<void> destruction_notifier; |
| std::future<void> future = destruction_notifier.get_future(); |
| transport->SetConnection(std::make_unique<UsbFfsConnection>( |
| std::move(control), std::move(bulk_out), std::move(bulk_in), |
| std::move(destruction_notifier))); |
| register_transport(transport); |
| future.wait(); |
| } |
| } |
| |
| void usb_init() { |
| bool use_nonblocking = android::base::GetBoolProperty( |
| "persist.adb.nonblocking_ffs", |
| android::base::GetBoolProperty("ro.adb.nonblocking_ffs", true)); |
| |
| if (use_nonblocking) { |
| std::thread(usb_ffs_open_thread).detach(); |
| } else { |
| usb_init_legacy(); |
| } |
| } |