Merge "Add freeCache API to ExternalStorageService"

3 files changed, 41 insertions, 0 deletions

diff --git a/core/java/android/os/storage/StorageManagerInternal.java b/core/java/android/os/storage/StorageManagerInternal.java
index 55ba15a5e57b..b12bb2ece4c2 100644
--- a/core/java/android/os/storage/StorageManagerInternal.java
+++ b/core/java/android/os/storage/StorageManagerInternal.java
@@ -101,4 +101,15 @@ public abstract class StorageManagerInternal {
      * Return true if uid is external storage service.
      */
     public abstract boolean isExternalStorageService(int uid);
+
+    /**
+     * Frees cache held by ExternalStorageService.
+     *
+     * <p> Blocks until the service frees the cache or fails in doing so.
+     *
+     * @param volumeUuid uuid of the {@link StorageVolume} from which cache needs to be freed,
+     *                   null value indicates private internal volume.
+     * @param bytes number of bytes which need to be freed
+     */
+    public abstract void freeCache(@Nullable String volumeUuid, long bytes);
 }
diff --git a/core/java/android/service/storage/ExternalStorageService.java b/core/java/android/service/storage/ExternalStorageService.java
index 3b4d84a1c668..0123c368583c 100644
--- a/core/java/android/service/storage/ExternalStorageService.java
+++ b/core/java/android/service/storage/ExternalStorageService.java
@@ -16,6 +16,7 @@
 
 package android.service.storage;
 
+import android.annotation.BytesLong;
 import android.annotation.IntDef;
 import android.annotation.NonNull;
 import android.annotation.SdkConstant;
@@ -29,6 +30,7 @@ import android.os.ParcelFileDescriptor;
 import android.os.ParcelableException;
 import android.os.RemoteCallback;
 import android.os.RemoteException;
+import android.os.storage.StorageManager;
 import android.os.storage.StorageVolume;
 
 import com.android.internal.os.BackgroundThread;
@@ -37,6 +39,7 @@ import java.io.File;
 import java.io.IOException;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.util.UUID;
 
 /**
  * A service to handle filesystem I/O from other apps.
@@ -147,6 +150,18 @@ public abstract class ExternalStorageService extends Service {
      */
     public abstract void onVolumeStateChanged(@NonNull StorageVolume vol) throws IOException;
 
+    /**
+     * Called when any cache held by the ExternalStorageService needs to be freed.
+     *
+     * <p> Blocks until the service frees the cache or fails in doing so.
+     *
+     * @param volumeUuid uuid of the {@link StorageVolume} from which cache needs to be freed
+     * @param bytes number of bytes which need to be freed
+     */
+    public void onFreeCacheRequested(@NonNull UUID volumeUuid, @BytesLong long bytes) {
+        throw new UnsupportedOperationException("onFreeCacheRequested not implemented");
+    }
+
     @Override
     @NonNull
     public final IBinder onBind(@NonNull Intent intent) {
@@ -183,6 +198,19 @@ public abstract class ExternalStorageService extends Service {
         }
 
         @Override
+        public void freeCache(String sessionId, String volumeUuid, long bytes,
+                RemoteCallback callback) {
+            mHandler.post(() -> {
+                try {
+                    onFreeCacheRequested(StorageManager.convert(volumeUuid), bytes);
+                    sendResult(sessionId, null /* throwable */, callback);
+                } catch (Throwable t) {
+                    sendResult(sessionId, t, callback);
+                }
+            });
+        }
+
+        @Override
         public void endSession(String sessionId, RemoteCallback callback) throws RemoteException {
             mHandler.post(() -> {
                 try {
diff --git a/core/java/android/service/storage/IExternalStorageService.aidl b/core/java/android/service/storage/IExternalStorageService.aidl
index 30fefd33016d..d06671b3fb9f 100644
--- a/core/java/android/service/storage/IExternalStorageService.aidl
+++ b/core/java/android/service/storage/IExternalStorageService.aidl
@@ -30,4 +30,6 @@ oneway interface IExternalStorageService
     void endSession(@utf8InCpp String sessionId, in RemoteCallback callback);
     void notifyVolumeStateChanged(@utf8InCpp String sessionId, in StorageVolume vol,
         in RemoteCallback callback);
+    void freeCache(@utf8InCpp String sessionId, in String volumeUuid, long bytes,
+        in RemoteCallback callback);
 }
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