Revert "Revert "[pm] remove old stage dirs on low storage""

This reverts commit b45ebca772.

Reason for revert: adding the fix for system to abandon sessions

BUG: 67862680
Test: manual
Change-Id: I5b762a29d12f62b516a59a85530386236259308b
Merged-In: I91170ba399b3a596320b3bd9c8188912e5c4f1be

services/core/java/com/android/server/pm/PackageInstallerService.java

@@ -134,6 +134,9 @@ public class PackageInstallerService extends IPackageInstaller.Stub implements
     /** Upper bound on number of historical sessions for a UID */
     private static final long MAX_HISTORICAL_SESSIONS = 1048576;
 
+    /** Destroy sessions older than this on storage free request */
+    private static final long MAX_SESSION_AGE_ON_LOW_STORAGE_MILLIS = 8 * DateUtils.HOUR_IN_MILLIS;
+
     /**
      * Allow verification-skipping if it's a development app installed through ADB with
      * disable verification flag specified.
@@ -295,22 +298,29 @@ public class PackageInstallerService extends IPackageInstaller.Stub implements
 
     @GuardedBy("mSessions")
     private void reconcileStagesLocked(String volumeUuid) {
-        final File stagingDir = getTmpSessionDir(volumeUuid);
-        final ArraySet<File> unclaimedStages = newArraySet(
-                stagingDir.listFiles(sStageFilter));
-
-        // We also need to clean up orphaned staging directory for staged sessions
-        final File stagedSessionStagingDir = Environment.getDataStagingDirectory(volumeUuid);
-        unclaimedStages.addAll(newArraySet(stagedSessionStagingDir.listFiles()));
 
+        final ArraySet<File> unclaimedStages = getStagingDirsOnVolume(volumeUuid);
         // Ignore stages claimed by active sessions
         for (int i = 0; i < mSessions.size(); i++) {
             final PackageInstallerSession session = mSessions.valueAt(i);
             unclaimedStages.remove(session.stageDir);
         }
+        removeStagingDirs(unclaimedStages);
+    }
 
+    private ArraySet<File> getStagingDirsOnVolume(String volumeUuid) {
+        final File stagingDir = getTmpSessionDir(volumeUuid);
+        final ArraySet<File> stagingDirs = newArraySet(stagingDir.listFiles(sStageFilter));
+
+        // We also need to clean up orphaned staging directory for staged sessions
+        final File stagedSessionStagingDir = Environment.getDataStagingDirectory(volumeUuid);
+        stagingDirs.addAll(newArraySet(stagedSessionStagingDir.listFiles()));
+        return stagingDirs;
+    }
+
+    private void removeStagingDirs(ArraySet<File> stagingDirsToRemove) {
         // Clean up orphaned staging directories
-        for (File stage : unclaimedStages) {
+        for (File stage : stagingDirsToRemove) {
             Slog.w(TAG, "Deleting orphan stage " + stage);
             synchronized (mPm.mInstallLock) {
                 mPm.removeCodePathLI(stage);
@@ -318,6 +328,34 @@ public class PackageInstallerService extends IPackageInstaller.Stub implements
         }
     }
 
+    /**
+     * Called to free up some storage space from obsolete installation files
+     */
+    public void freeStageDirs(String volumeUuid) {
+        final ArraySet<File> unclaimedStagingDirsOnVolume = getStagingDirsOnVolume(volumeUuid);
+        final long currentTimeMillis = System.currentTimeMillis();
+        synchronized (mSessions) {
+            for (int i = 0; i < mSessions.size(); i++) {
+                final PackageInstallerSession session = mSessions.valueAt(i);
+                if (!unclaimedStagingDirsOnVolume.contains(session.stageDir)) {
+                    // Only handles sessions stored on the target volume
+                    continue;
+                }
+                final long age = currentTimeMillis - session.createdMillis;
+                if (age >= MAX_SESSION_AGE_ON_LOW_STORAGE_MILLIS) {
+                    // Aggressively close old sessions because we are running low on storage
+                    // Their staging dirs will be removed too
+                    session.abandon();
+                } else {
+                    // Session is new enough, so it deserves to be kept even on low storage
+                    unclaimedStagingDirsOnVolume.remove(session.stageDir);
+                }
+            }
+        }
+        removeStagingDirs(unclaimedStagingDirsOnVolume);
+    }
+
+
     public void onPrivateVolumeMounted(String volumeUuid) {
         synchronized (mSessions) {
             reconcileStagesLocked(volumeUuid);

services/core/java/com/android/server/pm/PackageInstallerSession.java

@@ -2638,14 +2638,8 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
 
         List<PackageInstallerSession> childSessions = getChildSessionsNotLocked();
         synchronized (mLock) {
-            if (params.isStaged && mDestroyed) {
-                // If a user abandons staged session in an unsafe state, then system will try to
-                // abandon the destroyed staged session when it is safe on behalf of the user.
-                assertCallerIsOwnerOrRootOrSystemLocked();
-            } else {
-                assertCallerIsOwnerOrRootLocked();
-            }
 
+            assertCallerIsOwnerOrRootOrSystemLocked();
             if (isStagedAndInTerminalState()) {
                 // We keep the session in the database if it's in a finalized state. It will be
                 // removed by PackageInstallerService when the last update time is old enough.

services/core/java/com/android/server/pm/PackageManagerService.java

@@ -5140,6 +5140,10 @@ public class PackageManagerService extends IPackageManager.Stub
                             InstantAppRegistry.DEFAULT_UNINSTALLED_INSTANT_APP_MIN_CACHE_PERIOD))) {
                 return;
             }
+
+            // 12. Clear temp install session files
+            mInstallerService.freeStageDirs(volumeUuid);
+
         } else {
             try {
                 mInstaller.freeCache(volumeUuid, bytes, 0, 0);