Retry allocations in case of ENODEV am: b4f5426604 (5d5a91c0) · Commits · e / os / android_frameworks_av

media/mtp/MtpFfsHandle.cpp

+16 −2

Original line number	Diff line number	Diff line
		@@ -62,8 +62,13 @@ constexpr int MAX_FILE_CHUNK_SIZE = 3145728;
		constexpr int USB_FFS_MAX_WRITE = MTP_BUFFER_SIZE;
		constexpr int USB_FFS_MAX_READ = MTP_BUFFER_SIZE;

		static_assert(USB_FFS_MAX_WRITE > 0, "Max r/w values must be > 0!");
		static_assert(USB_FFS_MAX_READ > 0, "Max r/w values must be > 0!");

		constexpr unsigned int MAX_MTP_FILE_SIZE = 0xFFFFFFFF;

		constexpr size_t ENDPOINT_ALLOC_RETRIES = 10;

		struct func_desc {
		struct usb_interface_descriptor intf;
		struct usb_endpoint_descriptor_no_audio sink;
		@@ -459,19 +464,28 @@ int MtpFfsHandle::start() {
		mMaxWrite = android::base::GetIntProperty("sys.usb.ffs.max_write", USB_FFS_MAX_WRITE);
		mMaxRead = android::base::GetIntProperty("sys.usb.ffs.max_read", USB_FFS_MAX_READ);

		while (mMaxWrite > USB_FFS_MAX_WRITE && mMaxRead > USB_FFS_MAX_READ) {
		size_t attempts = 0;
		while (mMaxWrite >= USB_FFS_MAX_WRITE && mMaxRead >= USB_FFS_MAX_READ &&
		attempts < ENDPOINT_ALLOC_RETRIES) {
		// If larger contiguous chunks of memory aren't available, attempt to try
		// smaller allocations.
		if (ioctl(mBulkIn, FUNCTIONFS_ENDPOINT_ALLOC, static_cast<__u32>(mMaxWrite)) \|\|
		ioctl(mBulkOut, FUNCTIONFS_ENDPOINT_ALLOC, static_cast<__u32>(mMaxRead))) {
		if (errno == ENODEV) {
		// Driver hasn't enabled endpoints yet.
		std::this_thread::sleep_for(std::chrono::milliseconds(100));
		attempts += 1;
		continue;
		}
		mMaxWrite /= 2;
		mMaxRead /=2;
		} else {
		return 0;
		}
		}
		// Try to start MtpServer anyway, with the smallest max r/w values
		PLOG(ERROR) << "Functionfs could not allocate any memory!";
		return -1;
		return 0;
		}

		int MtpFfsHandle::configure(bool usePtp) {

media/mtp/MtpFfsHandle.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -59,6 +59,10 @@ public:
		int sendFile(mtp_file_range mfr);
		int sendEvent(mtp_event me);

		/**
		* Open ffs endpoints and allocate necessary kernel and user memory.
		* Will sleep until endpoints are enabled, for up to 1 second.
		*/
		int start();
		void close();