• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2019 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 #pragma once
18 
19 #include <sys/types.h>
20 #include <unistd.h>
21 
22 #include <string>
23 #include <vector>
24 #include <unordered_map>
25 
26 namespace android {
27 namespace dmabufinfo {
28 
29 struct DmaBuffer {
30   public:
DmaBufferDmaBuffer31     DmaBuffer(ino_t inode, uint64_t size, uint64_t count, const std::string& exporter,
32               const std::string& name)
33         : inode_(inode), size_(size), count_(count), exporter_(exporter), name_(name) {
34         total_refs_ = 0;
35     }
36     ~DmaBuffer() = default;
37 
38     // Adds one file descriptor reference for the given pid
AddFdRefDmaBuffer39     void AddFdRef(pid_t pid) {
40         AddRefToPidMap(pid, &fdrefs_);
41         total_refs_++;
42     }
43 
44     // Adds one map reference for the given pid
AddMapRefDmaBuffer45     void AddMapRef(pid_t pid) {
46         AddRefToPidMap(pid, &maprefs_);
47         total_refs_++;
48     }
49 
50     // Getters for each property
sizeDmaBuffer51     uint64_t size() const { return size_; }
fdrefsDmaBuffer52     const std::unordered_map<pid_t, int>& fdrefs() const { return fdrefs_; }
maprefsDmaBuffer53     const std::unordered_map<pid_t, int>& maprefs() const { return maprefs_; }
inodeDmaBuffer54     ino_t inode() const { return inode_; }
total_refsDmaBuffer55     uint64_t total_refs() const { return total_refs_; }
countDmaBuffer56     uint64_t count() const { return count_; };
nameDmaBuffer57     const std::string& name() const { return name_; }
exporterDmaBuffer58     const std::string& exporter() const { return exporter_; }
SetNameDmaBuffer59     void SetName(const std::string& name) { name_ = name; }
SetExporterDmaBuffer60     void SetExporter(const std::string& exporter) { exporter_ = exporter; }
SetCountDmaBuffer61     void SetCount(uint64_t count) { count_ = count; }
62 
63     bool operator==(const DmaBuffer& rhs) {
64         return (inode_ == rhs.inode()) && (size_ == rhs.size()) && (name_ == rhs.name()) &&
65                (exporter_ == rhs.exporter());
66     }
67 
68   private:
69     ino_t inode_;
70     uint64_t size_;
71     uint64_t count_;
72     uint64_t total_refs_;
73     std::string exporter_;
74     std::string name_;
75     std::unordered_map<pid_t, int> fdrefs_;
76     std::unordered_map<pid_t, int> maprefs_;
AddRefToPidMapDmaBuffer77     void AddRefToPidMap(pid_t pid, std::unordered_map<pid_t, int>* map) {
78         // The first time we find a ref, we set the ref count to 1
79         // otherwise, increment the existing ref count
80         auto [it, inserted] = map->insert(std::make_pair(pid, 1));
81         if (!inserted)
82             it->second++;
83     }
84 };
85 
86 // Read and return current dma buf objects from
87 // DEBUGFS/dma_buf/bufinfo. The references to each dma buffer are not
88 // populated here and will return an empty vector.
89 // Returns false if something went wrong with the function, true otherwise.
90 bool ReadDmaBufInfo(std::vector<DmaBuffer>* dmabufs,
91                     const std::string& path = "/sys/kernel/debug/dma_buf/bufinfo");
92 
93 
94 // Read and return dmabuf objects for a given process without the help
95 // of DEBUGFS
96 // Returns false if something went wrong with the function, true otherwise.
97 bool ReadDmaBufInfo(pid_t pid, std::vector<DmaBuffer>* dmabufs);
98 
99 // Append new dmabuf objects from a given process to an existing vector.
100 // When the vector contains an existing element with a matching inode,
101 // the reference counts will be updated.
102 // Does not depend on DEBUGFS.
103 // Returns false if something went wrong with the function, true otherwise.
104 bool AppendDmaBufInfo(pid_t pid, std::vector<DmaBuffer>* dmabufs);
105 
106 }  // namespace dmabufinfo
107 }  // namespace android
108