1 // Copyright (C) 2024 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 <memory>
18 #include <variant>
19 
20 #ifdef GFXSTREAM_BUILD_WITH_SNAPSHOT_FRONTEND_SUPPORT
21 #include "VirtioGpuResourceSnapshot.pb.h"
22 #endif
23 #include "aemu/base/AlignedBuf.h"
24 #include "aemu/base/memory/SharedMemory.h"
25 
26 namespace gfxstream {
27 namespace host {
28 
29 // LINT.IfChange(virtio_gpu_ring_blob)
30 
31 struct AlignedMemory {
32     void* addr = nullptr;
33 
AlignedMemoryAlignedMemory34     AlignedMemory(size_t align, size_t size) : addr(android::aligned_buf_alloc(align, size)) {}
35 
~AlignedMemoryAlignedMemory36     ~AlignedMemory() {
37         if (addr != nullptr) {
38             android::aligned_buf_free(addr);
39         }
40     }
41 
42     // AlignedMemory is neither copyable nor movable.
43     AlignedMemory(const AlignedMemory& other) = delete;
44     AlignedMemory& operator=(const AlignedMemory& other) = delete;
45     AlignedMemory(AlignedMemory&& other) = delete;
46     AlignedMemory& operator=(AlignedMemory&& other) = delete;
47 };
48 
49 // Memory used as a ring buffer for communication between the guest and host.
50 class RingBlob {
51    public:
52     static std::unique_ptr<RingBlob> CreateWithShmem(uint32_t id, uint64_t size);
53     static std::unique_ptr<RingBlob> CreateWithHostMemory(uint32_t, uint64_t size, uint64_t alignment);
54 
55     bool isExportable() const;
56 
57     // Only valid if `isExportable()` returns `true`.
58     android::base::SharedMemory::handle_type releaseHandle();
59 
60     void* map();
61 
size()62     uint64_t size() const { return mSize; }
63 
64 #ifdef GFXSTREAM_BUILD_WITH_SNAPSHOT_FRONTEND_SUPPORT
65     std::optional<gfxstream::host::snapshot::VirtioGpuRingBlobSnapshot> Snapshot();
66 
67     static std::optional<std::unique_ptr<RingBlob>> Restore(
68         const gfxstream::host::snapshot::VirtioGpuRingBlobSnapshot& snapshot);
69 #endif
70 
71   private:
72     RingBlob(uint32_t id,
73              uint64_t size,
74              uint64_t alignment,
75              std::variant<std::unique_ptr<AlignedMemory>,
76                           std::unique_ptr<android::base::SharedMemory>> memory);
77 
78     const uint64_t mId;
79     const uint64_t mSize;
80     const uint64_t mAlignment;
81     std::variant<std::unique_ptr<AlignedMemory>,
82                  std::unique_ptr<android::base::SharedMemory>> mMemory;
83 };
84 
85 // LINT.ThenChange(VirtioGpuRingBlobSnapshot.h:virtio_gpu_ring_blob)
86 
87 }  // namespace host
88 }  // namespace gfxstream
89