xref: /aosp_15_r20/system/core/fs_mgr/libsnapshot/snapuserd/include/snapuserd/dm_user_block_server.h (revision 00c7fec1bb09f3284aad6a6f96d2f63dfc3650ad)
1 // Copyright (C) 2023 The Android Open Source Project
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //      http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #pragma once
16 
17 #include <android-base/unique_fd.h>
18 
19 #include <string>
20 
21 #include <snapuserd/block_server.h>
22 #include <snapuserd/snapuserd_buffer.h>
23 #include <snapuserd/snapuserd_kernel.h>
24 
25 namespace android {
26 namespace snapshot {
27 
28 class DmUserBlockServer : public IBlockServer {
29   public:
30     DmUserBlockServer(const std::string& misc_name, android::base::unique_fd&& ctrl_fd,
31                       Delegate* delegate, size_t buffer_size);
32 
33     bool ProcessRequests() override;
34     void* GetResponseBuffer(size_t size, size_t to_write) override;
35     bool SendBufferedIo() override;
36     void SendError();
37 
38   private:
39     bool ProcessRequest(dm_user_header* header);
40     bool WriteDmUserPayload(size_t size);
41 
42     std::string misc_name_;
43     android::base::unique_fd ctrl_fd_;
44     Delegate* delegate_;
45 
46     // Per-request state.
47     BufferSink buffer_;
48     bool header_response_ = false;
49 };
50 
51 class DmUserBlockServerOpener : public IBlockServerOpener {
52   public:
53     DmUserBlockServerOpener(const std::string& misc_name, const std::string& dm_user_path);
54 
55     std::unique_ptr<IBlockServer> Open(IBlockServer::Delegate* delegate,
56                                        size_t buffer_size) override;
57 
58   private:
59     std::string misc_name_;
60     std::string dm_user_path_;
61 };
62 
63 class DmUserBlockServerFactory : public IBlockServerFactory {
64   public:
65     std::shared_ptr<IBlockServerOpener> CreateOpener(const std::string& misc_name) override;
66 };
67 
68 }  // namespace snapshot
69 }  // namespace android
70