Refactored Mtp driver interface into multiple classes.
Added new interface for FunctionFS. This allows most of
the driver code to exist in userspace. The driver will
automatically use FunctionFS if it is enabled for that
device, otherwise it will default to the kernel driver.
The intention is to eventually deprecate the kernel driver.
Bug: 30976142
Change-Id: I36b8d16ca254fddd995b3ea1bd3d37b0ff4a28f7
Test: New automated tests for MtpFfsHandle, AsyncIO.
Manual testing on each device.
diff --git a/media/mtp/AsyncIO.cpp b/media/mtp/AsyncIO.cpp
new file mode 100644
index 0000000..a1a98ab
--- /dev/null
+++ b/media/mtp/AsyncIO.cpp
@@ -0,0 +1,176 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#include <android-base/logging.h>
+#include <condition_variable>
+#include <memory>
+#include <mutex>
+#include <queue>
+
+#include "AsyncIO.h"
+
+namespace {
+
+void read_func(struct aiocb *aiocbp) {
+ aiocbp->ret = TEMP_FAILURE_RETRY(pread(aiocbp->aio_fildes,
+ aiocbp->aio_buf, aiocbp->aio_nbytes, aiocbp->aio_offset));
+ if (aiocbp->ret == -1) aiocbp->error = errno;
+}
+
+void write_func(struct aiocb *aiocbp) {
+ aiocbp->ret = TEMP_FAILURE_RETRY(pwrite(aiocbp->aio_fildes,
+ aiocbp->aio_buf, aiocbp->aio_nbytes, aiocbp->aio_offset));
+ if (aiocbp->ret == -1) aiocbp->error = errno;
+}
+
+void splice_read_func(struct aiocb *aiocbp) {
+ aiocbp->ret = TEMP_FAILURE_RETRY(splice(aiocbp->aio_fildes,
+ (off64_t*) &aiocbp->aio_offset, aiocbp->aio_sink,
+ NULL, aiocbp->aio_nbytes, 0));
+ if (aiocbp->ret == -1) aiocbp->error = errno;
+}
+
+void splice_write_func(struct aiocb *aiocbp) {
+ aiocbp->ret = TEMP_FAILURE_RETRY(splice(aiocbp->aio_fildes, NULL,
+ aiocbp->aio_sink, (off64_t*) &aiocbp->aio_offset,
+ aiocbp->aio_nbytes, 0));
+ if (aiocbp->ret == -1) aiocbp->error = errno;
+}
+
+std::queue<std::unique_ptr<struct aiocb>> queue;
+std::mutex queue_lock;
+std::condition_variable queue_cond;
+std::condition_variable write_cond;
+int done = 1;
+void splice_write_pool_func(int) {
+ while(1) {
+ std::unique_lock<std::mutex> lk(queue_lock);
+ queue_cond.wait(lk, []{return !queue.empty() || done;});
+ if (queue.empty() && done) {
+ return;
+ }
+ std::unique_ptr<struct aiocb> aiocbp = std::move(queue.front());
+ queue.pop();
+ lk.unlock();
+ write_cond.notify_one();
+ splice_write_func(aiocbp.get());
+ close(aiocbp->aio_fildes);
+ }
+}
+
+void write_pool_func(int) {
+ while(1) {
+ std::unique_lock<std::mutex> lk(queue_lock);
+ queue_cond.wait(lk, []{return !queue.empty() || done;});
+ if (queue.empty() && done) {
+ return;
+ }
+ std::unique_ptr<struct aiocb> aiocbp = std::move(queue.front());
+ queue.pop();
+ lk.unlock();
+ write_cond.notify_one();
+ aiocbp->ret = TEMP_FAILURE_RETRY(pwrite(aiocbp->aio_fildes,
+ aiocbp->aio_pool_buf.get(), aiocbp->aio_nbytes, aiocbp->aio_offset));
+ if (aiocbp->ret == -1) aiocbp->error = errno;
+ }
+}
+
+constexpr int NUM_THREADS = 1;
+constexpr int MAX_QUEUE_SIZE = 10;
+std::thread pool[NUM_THREADS];
+
+} // end anonymous namespace
+
+void aio_pool_init(void(f)(int)) {
+ CHECK(done == 1);
+ done = 0;
+ for (int i = 0; i < NUM_THREADS; i++) {
+ pool[i] = std::thread(f, i);
+ }
+}
+
+void aio_pool_splice_init() {
+ aio_pool_init(splice_write_pool_func);
+}
+
+void aio_pool_write_init() {
+ aio_pool_init(write_pool_func);
+}
+
+void aio_pool_end() {
+ done = 1;
+ for (int i = 0; i < NUM_THREADS; i++) {
+ std::unique_lock<std::mutex> lk(queue_lock);
+ lk.unlock();
+ queue_cond.notify_one();
+ }
+
+ for (int i = 0; i < NUM_THREADS; i++) {
+ pool[i].join();
+ }
+}
+
+// used for both writes and splices depending on which init was used before.
+int aio_pool_write(struct aiocb *aiocbp) {
+ std::unique_lock<std::mutex> lk(queue_lock);
+ write_cond.wait(lk, []{return queue.size() < MAX_QUEUE_SIZE;});
+ queue.push(std::unique_ptr<struct aiocb>(aiocbp));
+ lk.unlock();
+ queue_cond.notify_one();
+ return 0;
+}
+
+int aio_read(struct aiocb *aiocbp) {
+ aiocbp->thread = std::thread(read_func, aiocbp);
+ return 0;
+}
+
+int aio_write(struct aiocb *aiocbp) {
+ aiocbp->thread = std::thread(write_func, aiocbp);
+ return 0;
+}
+
+int aio_splice_read(struct aiocb *aiocbp) {
+ aiocbp->thread = std::thread(splice_read_func, aiocbp);
+ return 0;
+}
+
+int aio_splice_write(struct aiocb *aiocbp) {
+ aiocbp->thread = std::thread(splice_write_func, aiocbp);
+ return 0;
+}
+
+int aio_error(const struct aiocb *aiocbp) {
+ return aiocbp->error;
+}
+
+ssize_t aio_return(struct aiocb *aiocbp) {
+ return aiocbp->ret;
+}
+
+int aio_suspend(struct aiocb *aiocbp[], int n,
+ const struct timespec *) {
+ for (int i = 0; i < n; i++) {
+ aiocbp[i]->thread.join();
+ }
+ return 0;
+}
+
+int aio_cancel(int, struct aiocb *) {
+ // Not implemented
+ return -1;
+}
+