adb: Use kernel aio for functionfs.
This method works around the downsides of
ENDPOINT_ALLOC, namely that it is not affected
by memory fragmentation and it uses an upstream
interface.
Also add libasyncio to provide the necessary syscalls
to both adb and mtp.
Add some small optimizations to file_sync.
Bug: 37916658
Test: run adb push/pull
Change-Id: If3b3be02b5e2d4f9cffec1b8ddc02a5768a51a1f
diff --git a/adb/adb.h b/adb/adb.h
index d6b2b81..1b1065f 100644
--- a/adb/adb.h
+++ b/adb/adb.h
@@ -31,8 +31,7 @@
#include "usb.h"
constexpr size_t MAX_PAYLOAD_V1 = 4 * 1024;
-constexpr size_t MAX_PAYLOAD_V2 = 256 * 1024;
-constexpr size_t MAX_PAYLOAD = MAX_PAYLOAD_V2;
+constexpr size_t MAX_PAYLOAD = 1024 * 1024;
constexpr size_t LINUX_MAX_SOCKET_SIZE = 4194304;