Check eligibility before calling snapshotAndRestoreUserData

In cases where a rollback is not being enabled or a downgrade
is not taking place, PackageManagerService needlessly calls
into RollbackManagerService, giving the impression that a
userdata backup/restore is taking place. Performing this
eligibility check should make the post-install flow clearer.

Test: atest RollbackTest
Bug: 139920268
Change-Id: I7ccea264aefa24df52751647f45f38df4ae15cf4

1 files changed, 7 insertions, 3 deletions

diff --git a/services/core/java/com/android/server/pm/PackageManagerService.java b/services/core/java/com/android/server/pm/PackageManagerService.java
index 41403fdeeeef..e6c1c769c502 100644
--- a/services/core/java/com/android/server/pm/PackageManagerService.java
+++ b/services/core/java/com/android/server/pm/PackageManagerService.java
@@ -13853,7 +13853,7 @@ public class PackageManagerService extends IPackageManager.Stub
 
         // If this is an update to a package that might be potentially downgraded, then we
         // need to check with the rollback manager whether there's any userdata that might
-        // need to be restored for the package.
+        // need to be snapshotted or restored for the package.
         //
         // TODO(narayan): Get this working for cases where userId == UserHandle.USER_ALL.
         if (res.returnCode == PackageManager.INSTALL_SUCCEEDED && !doRestore && update) {
@@ -13880,12 +13880,16 @@ public class PackageManagerService extends IPackageManager.Stub
                 installedUsers = ps.queryInstalledUsers(allUsers, true);
             }
 
-            if (ps != null) {
+            boolean doSnapshotOrRestore = data != null && data.args != null
+                    && ((data.args.installFlags & PackageManager.INSTALL_ENABLE_ROLLBACK) != 0
+                    || (data.args.installFlags & PackageManager.INSTALL_REQUEST_DOWNGRADE) != 0);
+
+            if (ps != null && doSnapshotOrRestore) {
                 try {
                     rm.snapshotAndRestoreUserData(packageName, installedUsers, appId, ceDataInode,
                             seInfo, token);
                 } catch (RemoteException re) {
-                    // Cannot happen, the RollbackManager is hosted in the same process.
+                    Log.e(TAG, "Error snapshotting/restoring user data: " + re);
                 }
                 doRestore = true;
             }