Write descriptors for Mtp in UsbService
The current model for setting up a functionfs
function is:
UsbDeviceManager#setCurrentFunctions() ->
intent is sent to MtpReceiver to write the descriptors ->
init/hal waits for descriptors to write, then pulls up gadget ->
Gadget is configured, a USB_STATE intent starts MtpServer
The main downside of this is a lack of reliability because
the Mtp process could be killed at any point. Normally, a
gadget is unbound if its control endpoint is closed. no_disconnect
works around this, but is still a little janky. In addition, the
extra intent delays the startup of the gadget.
With the new model, UsbDeviceManager writes the descriptors
on initialization. Since it is a system service, it won't be killed.
UsbDeviceManager#setCurrentFunctions() ->
init/hal pulls up gadget ->
Gadget is configured, a USB_STATE intent starts MtpServer
MtpServer calls UsbManager#getControlFd to get a dup of the control
endpoint.
Also modify permissions so system server can access mtp files.
Bug: 72877174
Test: Change usb configurations to ptp/mtp
Change-Id: Id17d2b5930f4e1f37ec1b4f00add9d594174ad49
diff --git a/services/core/jni/Android.bp b/services/core/jni/Android.bp
index 427b9d2..89efe12 100644
--- a/services/core/jni/Android.bp
+++ b/services/core/jni/Android.bp
@@ -86,6 +86,7 @@
"libhardware_legacy",
"libhidlbase",
"libkeystore_binder",
+ "libmtp",
"libnativehelper",
"libutils",
"libui",
diff --git a/services/core/jni/com_android_server_UsbDeviceManager.cpp b/services/core/jni/com_android_server_UsbDeviceManager.cpp
index f37f870..ff1ec04 100644
--- a/services/core/jni/com_android_server_UsbDeviceManager.cpp
+++ b/services/core/jni/com_android_server_UsbDeviceManager.cpp
@@ -21,6 +21,7 @@
#include <nativehelper/JNIHelp.h>
#include "android_runtime/AndroidRuntime.h"
#include "android_runtime/Log.h"
+#include "MtpDescriptors.h"
#include <stdio.h>
#include <asm/byteorder.h>
@@ -118,6 +119,38 @@
return result;
}
+static jobject android_server_UsbDeviceManager_openControl(JNIEnv *env, jobject /* thiz */, jstring jFunction) {
+ const char *function = env->GetStringUTFChars(jFunction, NULL);
+ bool ptp = false;
+ int fd = -1;
+ if (!strcmp(function, "ptp")) {
+ ptp = true;
+ }
+ if (!strcmp(function, "mtp") || ptp) {
+ fd = TEMP_FAILURE_RETRY(open(ptp ? FFS_PTP_EP0 : FFS_MTP_EP0, O_RDWR));
+ if (fd < 0) {
+ ALOGE("could not open control for %s %s", function, strerror(errno));
+ goto error;
+ }
+ if (!writeDescriptors(fd, ptp)) {
+ goto error;
+ }
+ }
+
+ if (function != NULL) {
+ env->ReleaseStringUTFChars(jFunction, function);
+ }
+ return jniCreateFileDescriptor(env, fd);
+error:
+ if (fd != -1) {
+ close(fd);
+ }
+ if (function != NULL) {
+ env->ReleaseStringUTFChars(jFunction, function);
+ }
+ return NULL;
+}
+
static const JNINativeMethod method_table[] = {
{ "nativeGetAccessoryStrings", "()[Ljava/lang/String;",
(void*)android_server_UsbDeviceManager_getAccessoryStrings },
@@ -127,6 +160,8 @@
(void*)android_server_UsbDeviceManager_isStartRequested },
{ "nativeGetAudioMode", "()I",
(void*)android_server_UsbDeviceManager_getAudioMode },
+ { "nativeOpenControl", "(Ljava/lang/String;)Ljava/io/FileDescriptor;",
+ (void*)android_server_UsbDeviceManager_openControl },
};
int register_android_server_UsbDeviceManager(JNIEnv *env)
diff --git a/services/usb/java/com/android/server/usb/UsbDeviceManager.java b/services/usb/java/com/android/server/usb/UsbDeviceManager.java
index ef0780a..9f8042c 100644
--- a/services/usb/java/com/android/server/usb/UsbDeviceManager.java
+++ b/services/usb/java/com/android/server/usb/UsbDeviceManager.java
@@ -83,6 +83,7 @@
import com.android.server.LocalServices;
import java.io.File;
+import java.io.FileDescriptor;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.HashMap;
@@ -181,6 +182,7 @@
private final UEventObserver mUEventObserver;
private static Set<Integer> sBlackListedInterfaces;
+ private HashMap<Long, FileDescriptor> mControlFds;
static {
sBlackListedInterfaces = new HashSet<>();
@@ -270,6 +272,18 @@
Slog.i(TAG, "USB GADGET HAL not present in the device", e);
}
+ mControlFds = new HashMap<>();
+ FileDescriptor mtpFd = nativeOpenControl(UsbManager.USB_FUNCTION_MTP);
+ if (mtpFd == null) {
+ Slog.e(TAG, "Failed to open control for mtp");
+ }
+ mControlFds.put(UsbManager.FUNCTION_MTP, mtpFd);
+ FileDescriptor ptpFd = nativeOpenControl(UsbManager.USB_FUNCTION_PTP);
+ if (mtpFd == null) {
+ Slog.e(TAG, "Failed to open control for mtp");
+ }
+ mControlFds.put(UsbManager.FUNCTION_PTP, ptpFd);
+
boolean secureAdbEnabled = SystemProperties.getBoolean("ro.adb.secure", false);
boolean dataEncrypted = "1".equals(SystemProperties.get("vold.decrypt"));
if (secureAdbEnabled && !dataEncrypted) {
@@ -704,8 +718,7 @@
return false;
}
- protected void updateUsbStateBroadcastIfNeeded(long functions,
- boolean configChanged) {
+ protected void updateUsbStateBroadcastIfNeeded(long functions) {
// send a sticky broadcast containing current USB state
Intent intent = new Intent(UsbManager.ACTION_USB_STATE);
intent.addFlags(Intent.FLAG_RECEIVER_REPLACE_PENDING
@@ -716,7 +729,6 @@
intent.putExtra(UsbManager.USB_CONFIGURED, mConfigured);
intent.putExtra(UsbManager.USB_DATA_UNLOCKED,
isUsbTransferAllowed() && isUsbDataTransferActive(mCurrentFunctions));
- intent.putExtra(UsbManager.USB_CONFIG_CHANGED, configChanged);
long remainingFunctions = functions;
while (remainingFunctions != 0) {
@@ -726,7 +738,7 @@
}
// send broadcast intent only if the USB state has changed
- if (!isUsbStateChanged(intent) && !configChanged) {
+ if (!isUsbStateChanged(intent)) {
if (DEBUG) {
Slog.d(TAG, "skip broadcasting " + intent + " extras: " + intent.getExtras());
}
@@ -798,8 +810,7 @@
updateUsbNotification(false);
updateAdbNotification(false);
if (mBootCompleted) {
- updateUsbStateBroadcastIfNeeded(getAppliedFunctions(mCurrentFunctions),
- false);
+ updateUsbStateBroadcastIfNeeded(getAppliedFunctions(mCurrentFunctions));
}
if ((mCurrentFunctions & UsbManager.FUNCTION_ACCESSORY) != 0) {
updateCurrentAccessory();
@@ -812,7 +823,7 @@
&& mScreenUnlockedFunctions != UsbManager.FUNCTION_NONE) {
setScreenUnlockedFunctions();
} else {
- setEnabledFunctions(UsbManager.FUNCTION_NONE, !mAdbEnabled);
+ setEnabledFunctions(UsbManager.FUNCTION_NONE, false);
}
}
updateUsbFunctions();
@@ -847,8 +858,7 @@
updateUsbNotification(false);
if (mBootCompleted) {
if (mHostConnected || prevHostConnected) {
- updateUsbStateBroadcastIfNeeded(getAppliedFunctions(mCurrentFunctions),
- false);
+ updateUsbStateBroadcastIfNeeded(getAppliedFunctions(mCurrentFunctions));
}
} else {
mPendingBootBroadcast = true;
@@ -994,7 +1004,7 @@
protected void finishBoot() {
if (mBootCompleted && mCurrentUsbFunctionsReceived && mSystemReady) {
if (mPendingBootBroadcast) {
- updateUsbStateBroadcastIfNeeded(getAppliedFunctions(mCurrentFunctions), false);
+ updateUsbStateBroadcastIfNeeded(getAppliedFunctions(mCurrentFunctions));
mPendingBootBroadcast = false;
}
if (!mScreenLocked
@@ -1597,7 +1607,7 @@
/**
* Start up dependent services.
*/
- updateUsbStateBroadcastIfNeeded(getAppliedFunctions(mCurrentFunctions), true);
+ updateUsbStateBroadcastIfNeeded(getAppliedFunctions(mCurrentFunctions));
}
if (!waitForState(oemFunctions)) {
@@ -1943,7 +1953,7 @@
if (mBootCompleted && isUsbDataTransferActive(functions)) {
// Start up dependent services.
- updateUsbStateBroadcastIfNeeded(functions, true);
+ updateUsbStateBroadcastIfNeeded(functions);
}
}
}
@@ -1979,6 +1989,22 @@
return mHandler.getEnabledFunctions();
}
+ /**
+ * Returns a dup of the control file descriptor for the given function.
+ */
+ public ParcelFileDescriptor getControlFd(long usbFunction) {
+ FileDescriptor fd = mControlFds.get(usbFunction);
+ if (fd == null) {
+ return null;
+ }
+ try {
+ return ParcelFileDescriptor.dup(fd);
+ } catch (IOException e) {
+ Slog.e(TAG, "Could not dup fd for " + usbFunction);
+ return null;
+ }
+ }
+
public long getScreenUnlockedFunctions() {
return mHandler.getScreenUnlockedFunctions();
}
@@ -2063,6 +2089,8 @@
private native ParcelFileDescriptor nativeOpenAccessory();
+ private native FileDescriptor nativeOpenControl(String usbFunction);
+
private native boolean nativeIsStartRequested();
private native int nativeGetAudioMode();
diff --git a/services/usb/java/com/android/server/usb/UsbService.java b/services/usb/java/com/android/server/usb/UsbService.java
index c1a7591..e92bd74 100644
--- a/services/usb/java/com/android/server/usb/UsbService.java
+++ b/services/usb/java/com/android/server/usb/UsbService.java
@@ -304,6 +304,13 @@
return null;
}
+ /* Returns a dup of the control file descriptor for the given function. */
+ @Override
+ public ParcelFileDescriptor getControlFd(long function) {
+ mContext.enforceCallingOrSelfPermission(android.Manifest.permission.ACCESS_MTP, null);
+ return mDeviceManager.getControlFd(function);
+ }
+
@Override
public void setDevicePackage(UsbDevice device, String packageName, int userId) {
device = Preconditions.checkNotNull(device);