MTP FFS updates:
This update splits old MTP code and new MTP code from Google
into two trees, legacy and ffs. Depending on the SDK level,
the build system will select the correct version. The reason
for separating the versions out are due to older android trees
not supporting the updated MTP code from Google.
Most MTP code is from Google, with additions needed from
implementing the Java functions in C++ for TWRP and FFS.
We assume if you are in android-9.0 or above, your kernel
has support for FFS over MTP. Verify that your init.rc
is mounting the MTP FFS driver to the proper location.
Change-Id: I4b107b239bd9bc5699527f9c8c77d9079f264a7e
diff --git a/mtp/ffs/MtpFfsHandle.h b/mtp/ffs/MtpFfsHandle.h
new file mode 100644
index 0000000..20f74fa
--- /dev/null
+++ b/mtp/ffs/MtpFfsHandle.h
@@ -0,0 +1,112 @@
+/*
+ * 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.
+ */
+
+#ifndef _MTP_FFS_HANDLE_H
+#define _MTP_FFS_HANDLE_H
+
+#include <android-base/unique_fd.h>
+#include <linux/aio_abi.h>
+#include <mutex>
+#include <sys/poll.h>
+#include <time.h>
+#include <thread>
+#include <vector>
+
+#include <IMtpHandle.h>
+
+constexpr int NUM_IO_BUFS = 2;
+
+struct io_buffer {
+ std::vector<struct iocb> iocbs; // Holds memory for all iocbs. Not used directly.
+ std::vector<struct iocb*> iocb; // Pointers to individual iocbs, for syscalls
+ std::vector<unsigned char> bufs; // A large buffer, used with filesystem io
+ std::vector<unsigned char*> buf; // Pointers within the larger buffer, for syscalls
+ unsigned actual; // The number of buffers submitted for this request
+};
+
+template <class T> class MtpFfsHandleTest;
+
+class MtpFfsHandle : public IMtpHandle {
+ template <class T> friend class MtpFfsHandleTest;
+protected:
+ void closeConfig();
+ void closeEndpoints();
+ void advise(int fd);
+ int handleControlRequest(const struct usb_ctrlrequest *request);
+ int doAsync(void* data, size_t len, bool read, bool zero_packet);
+ int handleEvent();
+ void cancelTransaction();
+ void doSendEvent(mtp_event me);
+ bool openEndpoints(bool ptp);
+
+ static int getPacketSize(int ffs_fd);
+
+ bool mCanceled;
+
+ android::base::unique_fd mControl;
+ // "in" from the host's perspective => sink for mtp server
+ android::base::unique_fd mBulkIn;
+ // "out" from the host's perspective => source for mtp server
+ android::base::unique_fd mBulkOut;
+ android::base::unique_fd mIntr;
+
+ aio_context_t mCtx;
+
+ android::base::unique_fd mEventFd;
+ struct pollfd mPollFds[2];
+
+ struct io_buffer mIobuf[NUM_IO_BUFS];
+
+ // Submit an io request of given length. Return amount submitted or -1.
+ int iobufSubmit(struct io_buffer *buf, int fd, unsigned length, bool read);
+
+ // Cancel submitted requests from start to end in the given array. Return 0 or -1.
+ int cancelEvents(struct iocb **iocb, struct io_event *events, unsigned start, unsigned end);
+
+ // Wait for at minimum the given number of events. Returns the amount of data in the returned
+ // events. Increments counter by the number of events returned.
+ int waitEvents(struct io_buffer *buf, int min_events, struct io_event *events, int *counter);
+
+public:
+ int read(void *data, size_t len) override;
+ int write(const void *data, size_t len) override;
+
+ int receiveFile(mtp_file_range mfr, bool zero_packet) override;
+ int sendFile(mtp_file_range mfr) override;
+ int sendEvent(mtp_event me) override;
+
+ int start(bool ptp) override;
+ void close() override;
+
+ bool writeDescriptors(bool ptp);
+
+ MtpFfsHandle(int controlFd);
+ ~MtpFfsHandle();
+};
+
+struct mtp_data_header {
+ /* length of packet, including this header */
+ __le32 length;
+ /* container type (2 for data packet) */
+ __le16 type;
+ /* MTP command code */
+ __le16 command;
+ /* MTP transaction ID */
+ __le32 transaction_id;
+};
+
+#endif // _MTP_FFS_HANDLE_H
+