Merge "Stop idmap2d after several seconds pass" into qt-r1-dev

services/core/java/com/android/server/om/IdmapDaemon.java

@@ -0,0 +1,194 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+package com.android.server.om;
+
+import static android.content.Context.IDMAP_SERVICE;
+
+import static com.android.server.om.OverlayManagerService.DEBUG;
+import static com.android.server.om.OverlayManagerService.TAG;
+
+import android.os.IBinder;
+import android.os.IIdmap2;
+import android.os.RemoteException;
+import android.os.ServiceManager;
+import android.os.SystemProperties;
+import android.util.Slog;
+
+import com.android.server.FgThread;
+
+import java.util.concurrent.FutureTask;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * To prevent idmap2d from continuously running, the idmap daemon will terminate after 10
+ * seconds without a transaction.
+ **/
+class IdmapDaemon {
+    // The amount of time in milliseconds to wait after a transaction to the idmap service is made
+    // before stopping the service.
+    private static final int SERVICE_TIMEOUT_MS = 10000;
+
+    // The amount of time in milliseconds to wait when attempting to connect to idmap service.
+    private static final int SERVICE_CONNECT_TIMEOUT_MS = 5000;
+
+    private static final Object IDMAP_TOKEN = new Object();
+    private static final String IDMAP_DAEMON = "idmap2d";
+
+    private static IdmapDaemon sInstance;
+    private volatile IIdmap2 mService;
+    private final AtomicInteger mOpenedCount = new AtomicInteger();
+
+    /**
+     * An {@link AutoCloseable} connection to the idmap service. When the connection is closed or
+     * finalized, the idmap service will be stopped after a period of time unless another connection
+     * to the service is open.
+     **/
+    private class Connection implements AutoCloseable {
+        private boolean mOpened = true;
+
+        private Connection() {
+            synchronized (IDMAP_TOKEN) {
+                mOpenedCount.incrementAndGet();
+            }
+        }
+
+        @Override
+        public void close() {
+            synchronized (IDMAP_TOKEN) {
+                if (!mOpened) {
+                    return;
+                }
+
+                mOpened = false;
+                if (mOpenedCount.decrementAndGet() != 0) {
+                    // Only post the callback to stop the service if the service does not have an
+                    // open connection.
+                    return;
+                }
+
+                FgThread.getHandler().postDelayed(() -> {
+                    synchronized (IDMAP_TOKEN) {
+                        // Only stop the service if the service does not have an open connection.
+                        if (mService == null || mOpenedCount.get() != 0) {
+                            return;
+                        }
+
+                        stopIdmapService();
+                        mService = null;
+                    }
+                }, IDMAP_TOKEN, SERVICE_TIMEOUT_MS);
+            }
+        }
+    }
+
+    static IdmapDaemon getInstance() {
+        if (sInstance == null) {
+            sInstance = new IdmapDaemon();
+        }
+        return sInstance;
+    }
+
+    String createIdmap(String targetPath, String overlayPath, int policies, boolean enforce,
+            int userId) throws Exception {
+        try (Connection connection = connect()) {
+            return mService.createIdmap(targetPath, overlayPath, policies, enforce, userId);
+        }
+    }
+
+    boolean removeIdmap(String overlayPath, int userId) throws Exception {
+        try (Connection connection = connect()) {
+            return mService.removeIdmap(overlayPath, userId);
+        }
+    }
+
+    boolean verifyIdmap(String overlayPath, int policies, boolean enforce, int userId)
+            throws Exception {
+        try (Connection connection = connect()) {
+            return mService.verifyIdmap(overlayPath, policies, enforce, userId);
+        }
+    }
+
+    String getIdmapPath(String overlayPath, int userId) throws Exception {
+        try (Connection connection = connect()) {
+            return mService.getIdmapPath(overlayPath, userId);
+        }
+    }
+
+    static void startIdmapService() {
+        SystemProperties.set("ctl.start", IDMAP_DAEMON);
+    }
+
+    static void stopIdmapService() {
+        SystemProperties.set("ctl.stop", IDMAP_DAEMON);
+    }
+
+    private Connection connect() throws Exception {
+        synchronized (IDMAP_TOKEN) {
+            FgThread.getHandler().removeCallbacksAndMessages(IDMAP_TOKEN);
+            if (mService != null) {
+                // Not enough time has passed to stop the idmap service. Reuse the existing
+                // interface.
+                return new Connection();
+            }
+
+            // Start the idmap service if it is not currently running.
+            startIdmapService();
+
+            // Block until the service is found.
+            FutureTask<IBinder> bindIdmap = new FutureTask<>(() -> {
+                while (true) {
+                    try {
+                        IBinder binder = ServiceManager.getService(IDMAP_SERVICE);
+                        if (binder != null) {
+                            return binder;
+                        }
+                    } catch (Exception e) {
+                        Slog.e(TAG, "service '" + IDMAP_SERVICE + "' not retrieved; "
+                                + e.getMessage());
+                    }
+                    Thread.sleep(100);
+                }
+            });
+
+            IBinder binder;
+            try {
+                FgThread.getHandler().postAtFrontOfQueue(bindIdmap);
+                binder = bindIdmap.get(SERVICE_CONNECT_TIMEOUT_MS, TimeUnit.MILLISECONDS);
+            } catch (Exception rethrow) {
+                Slog.e(TAG, "service '" + IDMAP_SERVICE + "' not found;");
+                throw rethrow;
+            }
+
+            try {
+                binder.linkToDeath(() -> {
+                    Slog.w(TAG, "service '" + IDMAP_SERVICE + "' died");
+                }, 0);
+            } catch (RemoteException rethrow) {
+                Slog.e(TAG, "service '" + IDMAP_SERVICE + "' failed to be bound");
+                throw rethrow;
+            }
+
+            mService = IIdmap2.Stub.asInterface(binder);
+            if (DEBUG) {
+                Slog.d(TAG, "service '" + IDMAP_SERVICE + "' connected");
+            }
+
+            return new Connection();
+        }
+    }
+}

services/core/java/com/android/server/om/IdmapManager.java

@@ -16,9 +16,6 @@
 
 package com.android.server.om;
 
-import static android.content.Context.IDMAP_SERVICE;
-import static android.text.format.DateUtils.SECOND_IN_MILLIS;
-
 import static com.android.server.om.OverlayManagerService.DEBUG;
 import static com.android.server.om.OverlayManagerService.TAG;
 
@@ -27,15 +24,11 @@ import android.content.om.OverlayInfo;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageInfo;
 import android.os.Build.VERSION_CODES;
-import android.os.IBinder;
 import android.os.IIdmap2;
-import android.os.RemoteException;
-import android.os.ServiceManager;
 import android.os.SystemProperties;
 import android.os.UserHandle;
 import android.util.Slog;
 
-import com.android.internal.os.BackgroundThread;
 import com.android.server.om.OverlayManagerServiceImpl.PackageManagerHelper;
 import com.android.server.pm.Installer;
 
@@ -51,11 +44,6 @@ import java.io.File;
  */
 class IdmapManager {
     private static final boolean FEATURE_FLAG_IDMAP2 = true;
-
-    private final Installer mInstaller;
-    private final PackageManagerHelper mPackageManager;
-    private IIdmap2 mIdmap2Service;
-
     private static final boolean VENDOR_IS_Q_OR_LATER;
     static {
         final String value = SystemProperties.get("ro.vndk.version", "29");
@@ -70,12 +58,14 @@ class IdmapManager {
         VENDOR_IS_Q_OR_LATER = isQOrLater;
     }
 
+    private final Installer mInstaller;
+    private final PackageManagerHelper mPackageManager;
+    private final IdmapDaemon mIdmapDaemon;
+
     IdmapManager(final Installer installer, final PackageManagerHelper packageManager) {
         mInstaller = installer;
         mPackageManager = packageManager;
-        if (FEATURE_FLAG_IDMAP2) {
+        mIdmapDaemon = IdmapDaemon.getInstance();
-            connectToIdmap2d();
-        }
     }
 
     boolean createIdmap(@NonNull final PackageInfo targetPackage,
@@ -91,11 +81,11 @@ class IdmapManager {
             if (FEATURE_FLAG_IDMAP2) {
                 int policies = calculateFulfilledPolicies(targetPackage, overlayPackage, userId);
                 boolean enforce = enforceOverlayable(overlayPackage);
-                if (mIdmap2Service.verifyIdmap(overlayPath, policies, enforce, userId)) {
+                if (mIdmapDaemon.verifyIdmap(overlayPath, policies, enforce, userId)) {
                     return true;
                 }
-                return mIdmap2Service.createIdmap(targetPath, overlayPath, policies, enforce,
+                return mIdmapDaemon.createIdmap(targetPath, overlayPath, policies,
-                    userId) != null;
+                        enforce, userId) != null;
             } else {
                 mInstaller.idmap(targetPath, overlayPath, sharedGid);
                 return true;
@@ -113,7 +103,7 @@ class IdmapManager {
         }
         try {
             if (FEATURE_FLAG_IDMAP2) {
-                return mIdmap2Service.removeIdmap(oi.baseCodePath, userId);
+                return mIdmapDaemon.removeIdmap(oi.baseCodePath, userId);
             } else {
                 mInstaller.removeIdmap(oi.baseCodePath);
                 return true;
@@ -137,7 +127,7 @@ class IdmapManager {
             final int userId) {
         if (FEATURE_FLAG_IDMAP2) {
             try {
-                return mIdmap2Service.getIdmapPath(overlayPackagePath, userId);
+                return mIdmapDaemon.getIdmapPath(overlayPackagePath, userId);
             } catch (Exception e) {
                 Slog.w(TAG, "failed to get idmap path for " + overlayPackagePath + ": "
                         + e.getMessage());
@@ -151,35 +141,6 @@ class IdmapManager {
         }
     }
 
-    private void connectToIdmap2d() {
-        IBinder binder = ServiceManager.getService(IDMAP_SERVICE);
-        if (binder != null) {
-            try {
-                binder.linkToDeath(new IBinder.DeathRecipient() {
-                    @Override
-                    public void binderDied() {
-                        Slog.w(TAG, "service '" + IDMAP_SERVICE + "' died; reconnecting...");
-                        connectToIdmap2d();
-                    }
-
-                }, 0);
-            } catch (RemoteException e) {
-                binder = null;
-            }
-        }
-        if (binder != null) {
-            mIdmap2Service = IIdmap2.Stub.asInterface(binder);
-            if (DEBUG) {
-                Slog.d(TAG, "service '" + IDMAP_SERVICE + "' connected");
-            }
-        } else {
-            Slog.w(TAG, "service '" + IDMAP_SERVICE + "' not found; trying again...");
-            BackgroundThread.getHandler().postDelayed(() -> {
-                connectToIdmap2d();
-            }, SECOND_IN_MILLIS);
-        }
-    }
-
     /**
      * Checks if overlayable and policies should be enforced on the specified overlay for backwards
      * compatibility with pre-Q overlays.

services/core/java/com/android/server/om/OverlayManagerService.java

@@ -262,6 +262,7 @@ public final class OverlayManagerService extends SystemService {
 
             initIfNeeded();
             onSwitchUser(UserHandle.USER_SYSTEM);
+            IdmapDaemon.stopIdmapService();
 
             publishBinderService(Context.OVERLAY_SERVICE, mService);
             publishLocalService(OverlayManagerService.class, this);