1 /*
2  * Copyright (c) 2022 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 #include <sys/mman.h> /* mmap */
17 
18 #include "securec.h"
19 #include "pm_util.h"
20 #include "pm_state_c.h"
21 #include "pm_smartptr_util.h"
22 #include "pm_log.h"
23 
24 #include "purgeable_mem.h"
25 
26 namespace OHOS {
27 namespace PurgeableMem {
28 #ifdef LOG_TAG
29 #undef LOG_TAG
30 #endif
31 #define LOG_TAG "PurgeableMem"
32 
RoundUp(size_t val,size_t align)33 static inline size_t RoundUp(size_t val, size_t align)
34 {
35     if (val + align < val || val + align < align) {
36         PM_HILOG_ERROR(LOG_CORE, "%{public}s: Addition overflow!", __func__);
37         return val;
38     }
39     if (align == 0) {
40         return val;
41     }
42     return ((val + align - 1) / align) * align;
43 }
44 
PurgeableMem(size_t dataSize,std::unique_ptr<PurgeableMemBuilder> builder)45 PurgeableMem::PurgeableMem(size_t dataSize, std::unique_ptr<PurgeableMemBuilder> builder)
46 {
47     dataPtr_ = nullptr;
48     builder_ = nullptr;
49     pageTable_ = nullptr;
50     buildDataCount_ = 0;
51 
52     if (dataSize <= 0 || dataSize >= OHOS_MAXIMUM_PURGEABLE_MEMORY) {
53         PM_HILOG_DEBUG(LOG_CORE, "Failed to apply for memory");
54         return;
55     }
56     dataSizeInput_ = dataSize;
57     IF_NULL_LOG_ACTION(builder, "%{public}s: input builder nullptr", return);
58 
59     if (!CreatePurgeableData()) {
60         PM_HILOG_DEBUG(LOG_CORE, "Failed to create purgeabledata");
61         return;
62     }
63     builder_ = std::move(builder);
64     PM_HILOG_DEBUG(LOG_CORE, "%{public}s init succ. %{public}s", __func__, ToString().c_str());
65 }
66 
~PurgeableMem()67 PurgeableMem::~PurgeableMem()
68 {
69     PM_HILOG_DEBUG(LOG_CORE, "%{public}s %{public}s", __func__, ToString().c_str());
70     if (dataPtr_) {
71         if (munmap(dataPtr_, RoundUp(dataSizeInput_, PAGE_SIZE)) != 0) {
72             PM_HILOG_ERROR(LOG_CORE, "%{public}s: munmap dataPtr fail", __func__);
73         } else {
74             if (UxpteIsEnabled() && !IsPurged()) {
75                 PM_HILOG_ERROR(LOG_CORE, "%{public}s: munmap dataPtr succ, but uxpte present", __func__);
76             }
77             dataPtr_ = nullptr;
78         }
79     }
80     builder_.reset();
81     pageTable_.reset();
82 }
83 
IsPurged()84 bool PurgeableMem::IsPurged()
85 {
86     IF_NULL_LOG_ACTION(pageTable_, "pageTable_ is nullptrin BeginWrite", return false);
87     return !(pageTable_->CheckPresent((uint64_t)dataPtr_, dataSizeInput_));
88 }
89 
CreatePurgeableData()90 bool PurgeableMem::CreatePurgeableData()
91 {
92     PM_HILOG_DEBUG(LOG_CORE, "%{public}s", __func__);
93     pageTable_ = nullptr;
94     size_t size = RoundUp(dataSizeInput_, PAGE_SIZE);
95     unsigned int utype = MAP_ANONYMOUS;
96     utype |= (UxpteIsEnabled() ? MAP_PURGEABLE : MAP_PRIVATE);
97     int type = static_cast<int>(utype);
98 
99     dataPtr_ = mmap(nullptr, size, PROT_READ | PROT_WRITE, type, -1, 0);
100     if (dataPtr_ == MAP_FAILED) {
101         PM_HILOG_ERROR(LOG_CORE, "%{public}s: mmap fail", __func__);
102         dataPtr_ = nullptr;
103         return false;
104     }
105     MAKE_UNIQUE(pageTable_, UxPageTable, "constructor uxpt make_unique fail", return false, (uint64_t)dataPtr_, size);
106     return true;
107 }
108 
Pin()109 bool PurgeableMem::Pin()
110 {
111     IF_NULL_LOG_ACTION(pageTable_, "pageTable_ is nullptrin BeginWrite", return false);
112     pageTable_->GetUxpte((uint64_t)dataPtr_, dataSizeInput_);
113     return true;
114 }
115 
Unpin()116 bool PurgeableMem::Unpin()
117 {
118     IF_NULL_LOG_ACTION(pageTable_, "pageTable_ is nullptrin BeginWrite", return false);
119     pageTable_->PutUxpte((uint64_t)dataPtr_, dataSizeInput_);
120     return true;
121 }
122 
AfterRebuildSucc()123 void PurgeableMem::AfterRebuildSucc()
124 {
125 }
126 
GetPinStatus() const127 int PurgeableMem::GetPinStatus() const
128 {
129     return 0;
130 }
131 
ResizeData(size_t newSize)132 void PurgeableMem::ResizeData(size_t newSize)
133 {
134     if (newSize <= 0 || newSize >= OHOS_MAXIMUM_PURGEABLE_MEMORY) {
135         PM_HILOG_DEBUG(LOG_CORE, "Failed to apply for memory");
136         return;
137     }
138     if (dataPtr_) {
139         if (munmap(dataPtr_, RoundUp(dataSizeInput_, PAGE_SIZE)) != 0) {
140             PM_HILOG_ERROR(LOG_CORE, "%{public}s: munmap dataPtr fail", __func__);
141         } else {
142             dataPtr_ = nullptr;
143         }
144     }
145     dataSizeInput_ = newSize;
146     if (!CreatePurgeableData()) {
147         PM_HILOG_DEBUG(LOG_CORE, "Failed to create purgeabledata");
148         return;
149     }
150 }
151 
ToString() const152 inline std::string PurgeableMem::ToString() const
153 {
154     std::string dataptrStr = dataPtr_ ? std::to_string((unsigned long long)dataPtr_) : "0";
155     std::string pageTableStr = pageTable_ ? pageTable_->ToString() : "0";
156     return "dataAddr:" + dataptrStr + " dataSizeInput:" + std::to_string(dataSizeInput_) +
157         " " + pageTableStr;
158 }
159 } /* namespace PurgeableMem */
160 } /* namespace OHOS */
161