1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ANDROID_VOLD_EMULATED_VOLUME_H
18 #define ANDROID_VOLD_EMULATED_VOLUME_H
19 
20 #include "VolumeBase.h"
21 
22 #include <cutils/multiuser.h>
23 
24 namespace android {
25 namespace vold {
26 
27 /*
28  * Shared storage emulated on top of private storage.
29  *
30  * Knows how to spawn a sdcardfs daemon to synthesize permissions.  ObbVolume
31  * can be stacked above it.
32  *
33  * This volume is always multi-user aware, but is only binds itself to
34  * users when its primary storage.  This volume should never be presented
35  * as secondary storage, since we're strongly encouraging developers to
36  * store data local to their app.
37  */
38 class EmulatedVolume : public VolumeBase {
39   public:
40     explicit EmulatedVolume(const std::string& rawPath, int userId);
41     EmulatedVolume(const std::string& rawPath, dev_t device, const std::string& fsUuid, int userId);
42     virtual ~EmulatedVolume();
43     std::string getRootPath() const override;
isFuseMounted()44     bool isFuseMounted() const { return mFuseMounted; }
45 
46   protected:
47     status_t doMount() override;
48     status_t doUnmount() override;
49 
50   private:
51     status_t unmountSdcardFs();
52     status_t mountFuseBindMounts();
53     status_t unmountFuseBindMounts();
54 
55     std::string getLabel();
56     std::string mRawPath;
57     std::string mLabel;
58 
59     std::string mSdcardFsDefault;
60     std::string mSdcardFsRead;
61     std::string mSdcardFsWrite;
62     std::string mSdcardFsFull;
63 
64     /* Whether we mounted FUSE for this volume */
65     bool mFuseMounted;
66 
67     /* Whether to use sdcardfs for this volume */
68     bool mUseSdcardFs;
69 
70     /* Whether to use app data isolation is enabled tor this volume */
71     bool mAppDataIsolationEnabled;
72 
73     DISALLOW_COPY_AND_ASSIGN(EmulatedVolume);
74 };
75 
76 }  // namespace vold
77 }  // namespace android
78 
79 #endif
80