1 // Copyright (c) 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #ifndef GPU_COMMAND_BUFFER_COMMON_BUFFER_H_
6 #define GPU_COMMAND_BUFFER_COMMON_BUFFER_H_
7
8 #include <stddef.h>
9 #include <stdint.h>
10
11 #include <memory>
12
13 #include "base/macros.h"
14 #include "base/memory/ref_counted.h"
15 #include "base/memory/unsafe_shared_memory_region.h"
16 #include "base/trace_event/memory_allocator_dump.h"
17 #include "gpu/gpu_export.h"
18
19 namespace gpu {
20
21 class GPU_EXPORT BufferBacking {
22 public:
23 virtual ~BufferBacking() = default;
24 virtual const base::UnsafeSharedMemoryRegion& shared_memory_region() const;
25 virtual base::UnguessableToken GetGUID() const;
26 virtual void* GetMemory() const = 0;
27 virtual uint32_t GetSize() const = 0;
28 };
29
30 class GPU_EXPORT MemoryBufferBacking : public BufferBacking {
31 public:
32 explicit MemoryBufferBacking(uint32_t size);
33 ~MemoryBufferBacking() override;
34 void* GetMemory() const override;
35 uint32_t GetSize() const override;
36
37 private:
38 std::unique_ptr<char[]> memory_;
39 uint32_t size_;
40 DISALLOW_COPY_AND_ASSIGN(MemoryBufferBacking);
41 };
42
43
44 class GPU_EXPORT SharedMemoryBufferBacking : public BufferBacking {
45 public:
46 SharedMemoryBufferBacking(
47 base::UnsafeSharedMemoryRegion shared_memory_region,
48 base::WritableSharedMemoryMapping shared_memory_mapping);
49 ~SharedMemoryBufferBacking() override;
50 const base::UnsafeSharedMemoryRegion& shared_memory_region() const override;
51 base::UnguessableToken GetGUID() const override;
52 void* GetMemory() const override;
53 uint32_t GetSize() const override;
54
55 private:
56 base::UnsafeSharedMemoryRegion shared_memory_region_;
57 base::WritableSharedMemoryMapping shared_memory_mapping_;
58 DISALLOW_COPY_AND_ASSIGN(SharedMemoryBufferBacking);
59 };
60
61 // Buffer owns a piece of shared-memory of a certain size.
62 class GPU_EXPORT Buffer : public base::RefCountedThreadSafe<Buffer> {
63 public:
64 explicit Buffer(std::unique_ptr<BufferBacking> backing);
65
backing()66 BufferBacking* backing() const { return backing_.get(); }
memory()67 void* memory() const { return memory_; }
size()68 uint32_t size() const { return size_; }
69
70 // Returns nullptr if the address overflows the memory.
71 void* GetDataAddress(uint32_t data_offset, uint32_t data_size) const;
72
73 // Returns nullptr if the address overflows the memory.
74 void* GetDataAddressAndSize(uint32_t data_offset, uint32_t* data_size) const;
75
76 // Returns the remaining size of the buffer after an offset
77 uint32_t GetRemainingSize(uint32_t data_offset) const;
78
79 private:
80 friend class base::RefCountedThreadSafe<Buffer>;
81 ~Buffer();
82
83 std::unique_ptr<BufferBacking> backing_;
84 void* memory_;
85 uint32_t size_;
86
87 DISALLOW_COPY_AND_ASSIGN(Buffer);
88 };
89
MakeBackingFromSharedMemory(base::UnsafeSharedMemoryRegion shared_memory_region,base::WritableSharedMemoryMapping shared_memory_mapping)90 static inline std::unique_ptr<BufferBacking> MakeBackingFromSharedMemory(
91 base::UnsafeSharedMemoryRegion shared_memory_region,
92 base::WritableSharedMemoryMapping shared_memory_mapping) {
93 return std::make_unique<SharedMemoryBufferBacking>(
94 std::move(shared_memory_region), std::move(shared_memory_mapping));
95 }
MakeBufferFromSharedMemory(base::UnsafeSharedMemoryRegion shared_memory_region,base::WritableSharedMemoryMapping shared_memory_mapping)96 static inline scoped_refptr<Buffer> MakeBufferFromSharedMemory(
97 base::UnsafeSharedMemoryRegion shared_memory_region,
98 base::WritableSharedMemoryMapping shared_memory_mapping) {
99 return base::MakeRefCounted<Buffer>(MakeBackingFromSharedMemory(
100 std::move(shared_memory_region), std::move(shared_memory_mapping)));
101 }
102
MakeMemoryBuffer(uint32_t size)103 static inline scoped_refptr<Buffer> MakeMemoryBuffer(uint32_t size) {
104 return base::MakeRefCounted<Buffer>(
105 std::make_unique<MemoryBufferBacking>(size));
106 }
107
108 // Generates a process unique buffer ID which can be safely used with
109 // GetBufferGUIDForTracing.
110 GPU_EXPORT int32_t GetNextBufferId();
111
112 // Generates GUID which can be used to trace buffer using an Id.
113 GPU_EXPORT base::trace_event::MemoryAllocatorDumpGuid GetBufferGUIDForTracing(
114 uint64_t tracing_process_id,
115 int32_t buffer_id);
116
117 } // namespace gpu
118
119 #endif // GPU_COMMAND_BUFFER_COMMON_BUFFER_H_
120