Merge "Check if storage app data and obb directories exist in vold"

VoldNativeService.cpp

@@ -394,6 +394,14 @@ binder::Status VoldNativeService::setupAppDir(const std::string& path, int32_t a
     return translate(VolumeManager::Instance()->setupAppDir(path, appUid));
 }
 
+binder::Status VoldNativeService::ensureAppDirsCreated(const std::vector<std::string>& paths,
+        int32_t appUid) {
+    ENFORCE_SYSTEM_OR_ROOT;
+    ACQUIRE_LOCK;
+
+    return translate(VolumeManager::Instance()->ensureAppDirsCreated(paths, appUid));
+}
+
 binder::Status VoldNativeService::fixupAppDir(const std::string& path, int32_t appUid) {
     ENFORCE_SYSTEM_OR_ROOT;
     CHECK_ARGUMENT_PATH(path);

VoldNativeService.h

@@ -67,6 +67,7 @@ class VoldNativeService : public BinderService<VoldNativeService>, public os::Bn
     binder::Status remountAppStorageDirs(int uid, int pid,
                                const std::vector<std::string>& packageNames);
 
+    binder::Status ensureAppDirsCreated(const std::vector<std::string>& paths, int32_t appUid);
     binder::Status setupAppDir(const std::string& path, int32_t appUid);
     binder::Status fixupAppDir(const std::string& path, int32_t appUid);
 

VolumeManager.cpp

@@ -984,7 +984,25 @@ int VolumeManager::unmountAll() {
     return 0;
 }
 
-int VolumeManager::setupAppDir(const std::string& path, int32_t appUid, bool fixupExistingOnly) {
+int VolumeManager::ensureAppDirsCreated(const std::vector<std::string>& paths, int32_t appUid) {
+    if (IsSdcardfsUsed()) {
+        // sdcardfs magically does this for us
+        return OK;
+    }
+
+    int size = paths.size();
+    for (int i = 0; i < size; i++) {
+        int result = setupAppDir(paths[i], appUid, false /* fixupExistingOnly */,
+                true /* skipIfDirExists */);
+        if (result != OK) {
+            return result;
+        }
+    }
+    return OK;
+}
+
+int VolumeManager::setupAppDir(const std::string& path, int32_t appUid, bool fixupExistingOnly,
+        bool skipIfDirExists) {
     // Only offer to create directories for paths managed by vold
     if (!StartsWith(path, "/storage/")) {
         LOG(ERROR) << "Failed to find mounted volume for " << path;
@@ -1029,11 +1047,18 @@ int VolumeManager::setupAppDir(const std::string& path, int32_t appUid, bool fix
 
     const std::string volumeRoot = volume->getRootPath();  // eg /data/media/0
 
-    if (fixupExistingOnly && (access(lowerPath.c_str(), F_OK) != 0)) {
+    const int access_result = access(lowerPath.c_str(), F_OK);
+    if (fixupExistingOnly && access_result != 0) {
         // Nothing to fixup
         return OK;
     }
 
+    if (skipIfDirExists && access_result == 0) {
+        // It's safe to assume it's ok as it will be used for zygote to bind mount dir only,
+        // which the dir doesn't need to have correct permission for now yet.
+        return OK;
+    }
+
     if (volume->getType() == VolumeBase::Type::kPublic) {
         // On public volumes, we don't need to setup permissions, as everything goes through
         // FUSE; just create the dirs and be done with it.

VolumeManager.h

@@ -165,12 +165,16 @@ class VolumeManager {
      * files in the passed in path, but only if that path exists; if it doesn't
      * exist, this function doesn't create them.
      *
+     * If skipIfDirExists is set, we will not fix any existing dirs, we will
+     * only create app dirs if it doesn't exist.
+     *
      * Validates that given paths are absolute and that they contain no relative
      * "." or ".." paths or symlinks.  Last path segment is treated as filename
      * and ignored, unless the path ends with "/".  Also ensures that path
      * belongs to a volume managed by vold.
      */
-    int setupAppDir(const std::string& path, int32_t appUid, bool fixupExistingOnly = false);
+    int setupAppDir(const std::string& path, int32_t appUid, bool fixupExistingOnly = false,
+            bool skipIfDirExists = false);
 
     /**
      * Fixes up an existing application directory, as if it was created with
@@ -179,6 +183,9 @@ class VolumeManager {
      */
     int fixupAppDir(const std::string& path, int32_t appUid);
 
+    // Called before zygote starts to ensure dir exists so zygote can bind mount them.
+    int ensureAppDirsCreated(const std::vector<std::string>& paths, int32_t appUid);
+
     int createObb(const std::string& path, const std::string& key, int32_t ownerGid,
                   std::string* outVolId);
     int destroyObb(const std::string& volId);

binder/android/os/IVold.aidl

@@ -57,6 +57,7 @@ interface IVold {
 
     void setupAppDir(@utf8InCpp String path, int appUid);
     void fixupAppDir(@utf8InCpp String path, int appUid);
+    void ensureAppDirsCreated(in @utf8InCpp String[] paths, int appUid);
 
     @utf8InCpp String createObb(@utf8InCpp String sourcePath, @utf8InCpp String sourceKey,
                                 int ownerGid);