Pass bind mount storage data decision from java to zygote

Before we used store dirty data in system property to record
if FUSE for a user is mounted, and zygote uses it to determine
if storage mount is needed. It introduces performance issues and
not reliable.

This CL does the following changes:

- System server determines if storage dirs mount are needed, and store
the record inside system server.

- It passes the verdict to zygote so zygote just need to follow the
input.

- When emulated storage is mounted / unmounted, it will record if
FUSE for that user is ready to use, and will be used for determining
if storage dirs mount are needed when a new process starts.

- After emulated storage is mounted, it will create an async thread
to remount all storage dirs for existing app processes. As we have a
record of pids that storage dirs are not mounted yet, we can use it
directly without scanning the whole /proc in vold.

Bug: 149548518
Test: After flag is enabled, AdoptableHostTest still pass.
Change-Id: Ic99d027d42b2b9a1c7fd03070b36c44882c6e7c5

1 files changed, 4 insertions, 2 deletions

diff --git a/core/java/android/os/Process.java b/core/java/android/os/Process.java
index d7af1b9faa97..a557bd994c13 100644
--- a/core/java/android/os/Process.java
+++ b/core/java/android/os/Process.java
@@ -607,6 +607,7 @@ public class Process {
      *                             started.
      * @param pkgDataInfoMap Map from related package names to private data directory
      *                       volume UUID and inode number.
+     * @param bindMountAppStorageDirs whether zygote needs to mount Android/obb and Android/data.
      * @param zygoteArgs Additional arguments to supply to the zygote process.
      * @return An object that describes the result of the attempt to start the process.
      * @throws RuntimeException on fatal start failure
@@ -630,12 +631,13 @@ public class Process {
                                            @Nullable long[] disabledCompatChanges,
                                            @Nullable Map<String, Pair<String, Long>>
                                                    pkgDataInfoMap,
+                                           boolean bindMountAppStorageDirs,
                                            @Nullable String[] zygoteArgs) {
         return ZYGOTE_PROCESS.start(processClass, niceName, uid, gid, gids,
                     runtimeFlags, mountExternal, targetSdkVersion, seInfo,
                     abi, instructionSet, appDataDir, invokeWith, packageName,
                     zygotePolicyFlags, isTopApp, disabledCompatChanges,
-                    pkgDataInfoMap, zygoteArgs);
+                    pkgDataInfoMap, bindMountAppStorageDirs, zygoteArgs);
     }
 
     /** @hide */
@@ -659,7 +661,7 @@ public class Process {
                     runtimeFlags, mountExternal, targetSdkVersion, seInfo,
                     abi, instructionSet, appDataDir, invokeWith, packageName,
                     /*zygotePolicyFlags=*/ ZYGOTE_POLICY_FLAG_EMPTY, /*isTopApp=*/ false,
-                disabledCompatChanges, /* pkgDataInfoMap */ null, zygoteArgs);
+                disabledCompatChanges, /* pkgDataInfoMap */ null, false, zygoteArgs);
     }
 
     /**