From 2991cbe49fb54bbdfaabb392b59bb495c2aae605 Mon Sep 17 00:00:00 2001
From: Youkichi Hosoi <youkichihosoi@google.com>
Date: Thu, 11 Nov 2021 11:23:01 +0900
Subject: [PATCH] Split MOUNT_FLAG_VISIBLE into MOUNT_FLAG_VISIBLE_FOR_{READ,
 WRITE}

IVold.MOUNT_FLAG_VISIBLE is split into MOUNT_FLAG_VISIBLE_FOR_READ and
MOUNT_FLAG_VISIBLE_FOR_WRITE.
Accordingly, VolumeBase::MountFlags::kVisible is split into
kVisibleForRead and kVisibleForWrite.

Bug: 206019156
Test: m
Change-Id: Ia55673400d9f713f221650e1335a46ba11f6f027
Merged-In: Ia55673400d9f713f221650e1335a46ba11f6f027
---
 VolumeManager.cpp            |  8 ++++----
 binder/android/os/IVold.aidl |  3 ++-
 model/EmulatedVolume.cpp     |  2 +-
 model/PublicVolume.cpp       |  2 +-
 model/VolumeBase.h           | 13 +++++++++++--
 5 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/VolumeManager.cpp b/VolumeManager.cpp
index d299593..02025b7 100644
--- a/VolumeManager.cpp
+++ b/VolumeManager.cpp
@@ -1002,8 +1002,8 @@ int VolumeManager::setupAppDir(const std::string& path, int32_t appUid, bool fix
             // The volume must be mounted
             return false;
         }
-        if ((vol.getMountFlags() & VolumeBase::MountFlags::kVisible) == 0) {
-            // and visible
+        if (!vol.isVisibleForWrite()) {
+            // App dirs should only be created for writable volumes.
             return false;
         }
         if (vol.getInternalPath().empty()) {
@@ -1077,8 +1077,8 @@ int VolumeManager::createObb(const std::string& sourcePath, const std::string& s
                 // The volume must be mounted
                 return false;
             }
-            if ((vol.getMountFlags() & VolumeBase::MountFlags::kVisible) == 0) {
-                // and visible
+            if (!vol.isVisibleForWrite()) {
+                // Obb volume should only be created for writable volumes.
                 return false;
             }
             if (vol.getInternalPath().empty()) {
diff --git a/binder/android/os/IVold.aidl b/binder/android/os/IVold.aidl
index 606f473..8dd7860 100644
--- a/binder/android/os/IVold.aidl
+++ b/binder/android/os/IVold.aidl
@@ -159,7 +159,8 @@ interface IVold {
     const int FSTRIM_FLAG_DEEP_TRIM = 1;
 
     const int MOUNT_FLAG_PRIMARY = 1;
-    const int MOUNT_FLAG_VISIBLE = 2;
+    const int MOUNT_FLAG_VISIBLE_FOR_READ = 2;
+    const int MOUNT_FLAG_VISIBLE_FOR_WRITE = 4;
 
     const int PARTITION_TYPE_PUBLIC = 0;
     const int PARTITION_TYPE_PRIVATE = 1;
diff --git a/model/EmulatedVolume.cpp b/model/EmulatedVolume.cpp
index 6f21ff8..b686437 100644
--- a/model/EmulatedVolume.cpp
+++ b/model/EmulatedVolume.cpp
@@ -246,7 +246,7 @@ status_t EmulatedVolume::unmountSdcardFs() {
 
 status_t EmulatedVolume::doMount() {
     std::string label = getLabel();
-    bool isVisible = getMountFlags() & MountFlags::kVisible;
+    bool isVisible = isVisibleForWrite();
 
     mSdcardFsDefault = StringPrintf("/mnt/runtime/default/%s", label.c_str());
     mSdcardFsRead = StringPrintf("/mnt/runtime/read/%s", label.c_str());
diff --git a/model/PublicVolume.cpp b/model/PublicVolume.cpp
index 12e31ff..bf54c95 100644
--- a/model/PublicVolume.cpp
+++ b/model/PublicVolume.cpp
@@ -97,7 +97,7 @@ status_t PublicVolume::doDestroy() {
 }
 
 status_t PublicVolume::doMount() {
-    bool isVisible = getMountFlags() & MountFlags::kVisible;
+    bool isVisible = isVisibleForWrite();
     readMetadata();
 
     if (mFsType == "vfat" && vfat::IsSupported()) {
diff --git a/model/VolumeBase.h b/model/VolumeBase.h
index 689750d..f29df65 100644
--- a/model/VolumeBase.h
+++ b/model/VolumeBase.h
@@ -63,8 +63,14 @@ class VolumeBase {
     enum MountFlags {
         /* Flag that volume is primary external storage */
         kPrimary = 1 << 0,
-        /* Flag that volume is visible to normal apps */
-        kVisible = 1 << 1,
+        /*
+         * Flags indicating that volume is visible to normal apps.
+         * kVisibleForRead and kVisibleForWrite correspond to
+         * VolumeInfo.MOUNT_FLAG_VISIBLE_FOR_READ and
+         * VolumeInfo.MOUNT_FLAG_VISIBLE_FOR_WRITE, respectively.
+         */
+        kVisibleForRead = 1 << 1,
+        kVisibleForWrite = 1 << 2,
     };
 
     enum class State {
@@ -103,6 +109,9 @@ class VolumeBase {
     std::shared_ptr<VolumeBase> findVolume(const std::string& id);
 
     bool isEmulated() { return mType == Type::kEmulated; }
+    bool isVisibleForRead() const { return (mMountFlags & MountFlags::kVisibleForRead) != 0; }
+    bool isVisibleForWrite() const { return (mMountFlags & MountFlags::kVisibleForWrite) != 0; }
+    bool isVisible() const { return isVisibleForRead() || isVisibleForWrite(); }
 
     status_t create();
     status_t destroy();