1 /* 2 * Copyright (c) 2023 Huawei Device Co., Ltd. 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 16 #ifndef OHOS_UTILS_MEMORY_LIBPURGEABLEMEM_CPP_INCLUDE_PURGEABLE_MEM_BASE_H 17 #define OHOS_UTILS_MEMORY_LIBPURGEABLEMEM_CPP_INCLUDE_PURGEABLE_MEM_BASE_H 18 19 #ifndef OHOS_MAXIMUM_PURGEABLE_MEMORY 20 #define OHOS_MAXIMUM_PURGEABLE_MEMORY ((1024) * (1024) * (1024)) /* 1G */ 21 #endif /* OHOS_MAXIMUM_PURGEABLE_MEMORY */ 22 23 #include <memory> /* unique_ptr */ 24 #include <shared_mutex> /* shared_mutex */ 25 #include <string> 26 27 #include "purgeable_mem_builder.h" 28 #include "ux_page_table.h" 29 30 namespace OHOS { 31 namespace PurgeableMem { 32 class PurgeableMemBase { 33 public: 34 /* 35 * BeginRead: begin read the PurgeableMem obj. 36 * Return: return true if the obj's content is present. 37 * If content is purged(no present), system will recover its data, 38 * return false if content is purged and recover failed. 39 * While return true if content recover success. 40 * OS cannot reclaim the memory of the obj's content when this 41 * function return true, until EndRead() is called. 42 */ 43 bool BeginRead(); 44 45 /* 46 * EndRead: end read the PurgeableMem obj. 47 * OS may reclaim the memory of its content 48 * at a later time when this function returns. 49 */ 50 void EndRead(); 51 52 /* 53 * BeginRead: begin read the PurgeableMem obj. 54 * Return: return true if the obj's content is present. 55 * If content is purged(no present), system will recover its data, 56 * return false if content is purged and recover failed. 57 * While return true if content recover success. 58 * OS cannot reclaim the memory of the obj's content when this 59 * function return true, until EndRead() is called. 60 */ 61 62 bool BeginWrite(); 63 64 /* 65 * EndWrite: end write the PurgeableMem obj. 66 * OS may reclaim the memory of its content 67 * at a later time when this function returns. 68 */ 69 void EndWrite(); 70 71 /* 72 * ModifyContentByBuilder: append a PurgeableMemBuilder obj to the PurgeableMem obj. 73 * Input: @modifier: unique_ptr of PurgeableMemBuilder, it will modify content of this obj. 74 * Return: modify result, true is success, while false is fail. 75 * This function should be protected by BeginWrite()/EndWrite(). 76 */ 77 bool ModifyContentByBuilder(std::unique_ptr<PurgeableMemBuilder> modifier); 78 79 /* 80 * GetContent: get content ptr of the PurgeableMem obj. 81 * Return: return the content ptr, which is start address of the obj's content. 82 * This function should be protected by BeginRead()/EndRead() 83 * or BeginWrite()/EndWrite(). 84 */ 85 void *GetContent(); 86 87 /* 88 * GetContentSize: get content size of the PurgeableMem obj. 89 * Return: return content size of the obj's content. 90 */ 91 size_t GetContentSize(); 92 93 /* 94 * ResizeData: resize size of the PurgeableMem obj. 95 */ 96 virtual void ResizeData(size_t newSize); 97 void SetRebuildSuccessCallback(std::function<void()> &callback); 98 bool IsDataValid(); 99 void SetDataValid(bool target); 100 bool BeginReadWithDataLock(); 101 void EndReadWithDataLock(); 102 103 PurgeableMemBase(); 104 virtual ~PurgeableMemBase(); 105 PurgeableMemBase(const PurgeableMemBase&) = delete; 106 PurgeableMemBase& operator = (PurgeableMemBase&) = delete; 107 PurgeableMemBase(PurgeableMemBase&&) noexcept = delete; 108 PurgeableMemBase& operator = (PurgeableMemBase&&) noexcept = delete; 109 110 protected: 111 void *dataPtr_ = nullptr; 112 std::mutex dataLock_; 113 bool isDataValid_ {true}; 114 size_t dataSizeInput_ = 0; 115 std::unique_ptr<PurgeableMemBuilder> builder_ = nullptr; 116 std::shared_mutex rwlock_; 117 unsigned int buildDataCount_ = 0; 118 bool BuildContent(); 119 bool IfNeedRebuild(); 120 virtual bool Pin(); 121 virtual bool Unpin(); 122 virtual bool IsPurged(); 123 virtual int GetPinStatus() const; 124 virtual void AfterRebuildSucc(); 125 virtual std::string ToString() const; 126 }; 127 } /* namespace PurgeableMem */ 128 } /* namespace OHOS */ 129 #endif /* OHOS_UTILS_MEMORY_LIBPURGEABLEMEM_CPP_INCLUDE_PURGEABLE_MEM_BASE_H */ 130