1 /*
2 * Copyright (C) 2008 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 #define LOG_TAG "MemoryHeapBase"
18
19 #include <stdlib.h>
20 #include <stdint.h>
21 #include <unistd.h>
22 #include <fcntl.h>
23 #include <errno.h>
24 #include <sys/types.h>
25 #include <sys/stat.h>
26 #include <sys/ioctl.h>
27
28 #include <cutils/log.h>
29 #include <cutils/ashmem.h>
30 #include <cutils/atomic.h>
31
32 #include <binder/MemoryHeapBase.h>
33
34 #ifdef HAVE_ANDROID_OS
35 #include <linux/android_pmem.h>
36 #endif
37
38
39 namespace android {
40
41 // ---------------------------------------------------------------------------
42
MemoryHeapBase()43 MemoryHeapBase::MemoryHeapBase()
44 : mFD(-1), mSize(0), mBase(MAP_FAILED),
45 mDevice(NULL), mNeedUnmap(false), mOffset(0)
46 {
47 }
48
MemoryHeapBase(size_t size,uint32_t flags,char const * name)49 MemoryHeapBase::MemoryHeapBase(size_t size, uint32_t flags, char const * name)
50 : mFD(-1), mSize(0), mBase(MAP_FAILED), mFlags(flags),
51 mDevice(0), mNeedUnmap(false), mOffset(0)
52 {
53 const size_t pagesize = getpagesize();
54 size = ((size + pagesize-1) & ~(pagesize-1));
55 int fd = ashmem_create_region(name == NULL ? "MemoryHeapBase" : name, size);
56 LOGE_IF(fd<0, "error creating ashmem region: %s", strerror(errno));
57 if (fd >= 0) {
58 if (mapfd(fd, size) == NO_ERROR) {
59 if (flags & READ_ONLY) {
60 ashmem_set_prot_region(fd, PROT_READ);
61 }
62 }
63 }
64 }
65
MemoryHeapBase(const char * device,size_t size,uint32_t flags)66 MemoryHeapBase::MemoryHeapBase(const char* device, size_t size, uint32_t flags)
67 : mFD(-1), mSize(0), mBase(MAP_FAILED), mFlags(flags),
68 mDevice(0), mNeedUnmap(false), mOffset(0)
69 {
70 int open_flags = O_RDWR;
71 if (flags & NO_CACHING)
72 open_flags |= O_SYNC;
73
74 int fd = open(device, open_flags);
75 LOGE_IF(fd<0, "error opening %s: %s", device, strerror(errno));
76 if (fd >= 0) {
77 const size_t pagesize = getpagesize();
78 size = ((size + pagesize-1) & ~(pagesize-1));
79 if (mapfd(fd, size) == NO_ERROR) {
80 mDevice = device;
81 }
82 }
83 }
84
MemoryHeapBase(int fd,size_t size,uint32_t flags,uint32_t offset)85 MemoryHeapBase::MemoryHeapBase(int fd, size_t size, uint32_t flags, uint32_t offset)
86 : mFD(-1), mSize(0), mBase(MAP_FAILED), mFlags(flags),
87 mDevice(0), mNeedUnmap(false), mOffset(0)
88 {
89 const size_t pagesize = getpagesize();
90 size = ((size + pagesize-1) & ~(pagesize-1));
91 mapfd(dup(fd), size, offset);
92 }
93
init(int fd,void * base,int size,int flags,const char * device)94 status_t MemoryHeapBase::init(int fd, void *base, int size, int flags, const char* device)
95 {
96 if (mFD != -1) {
97 return INVALID_OPERATION;
98 }
99 mFD = fd;
100 mBase = base;
101 mSize = size;
102 mFlags = flags;
103 mDevice = device;
104 return NO_ERROR;
105 }
106
mapfd(int fd,size_t size,uint32_t offset)107 status_t MemoryHeapBase::mapfd(int fd, size_t size, uint32_t offset)
108 {
109 if (size == 0) {
110 // try to figure out the size automatically
111 #ifdef HAVE_ANDROID_OS
112 // first try the PMEM ioctl
113 pmem_region reg;
114 int err = ioctl(fd, PMEM_GET_TOTAL_SIZE, ®);
115 if (err == 0)
116 size = reg.len;
117 #endif
118 if (size == 0) { // try fstat
119 struct stat sb;
120 if (fstat(fd, &sb) == 0)
121 size = sb.st_size;
122 }
123 // if it didn't work, let mmap() fail.
124 }
125
126 if ((mFlags & DONT_MAP_LOCALLY) == 0) {
127 void* base = (uint8_t*)mmap(0, size,
128 PROT_READ|PROT_WRITE, MAP_SHARED, fd, offset);
129 if (base == MAP_FAILED) {
130 LOGE("mmap(fd=%d, size=%u) failed (%s)",
131 fd, uint32_t(size), strerror(errno));
132 close(fd);
133 return -errno;
134 }
135 //LOGD("mmap(fd=%d, base=%p, size=%lu)", fd, base, size);
136 mBase = base;
137 mNeedUnmap = true;
138 } else {
139 mBase = 0; // not MAP_FAILED
140 mNeedUnmap = false;
141 }
142 mFD = fd;
143 mSize = size;
144 mOffset = offset;
145 return NO_ERROR;
146 }
147
~MemoryHeapBase()148 MemoryHeapBase::~MemoryHeapBase()
149 {
150 dispose();
151 }
152
dispose()153 void MemoryHeapBase::dispose()
154 {
155 int fd = android_atomic_or(-1, &mFD);
156 if (fd >= 0) {
157 if (mNeedUnmap) {
158 //LOGD("munmap(fd=%d, base=%p, size=%lu)", fd, mBase, mSize);
159 munmap(mBase, mSize);
160 }
161 mBase = 0;
162 mSize = 0;
163 close(fd);
164 }
165 }
166
getHeapID() const167 int MemoryHeapBase::getHeapID() const {
168 return mFD;
169 }
170
getBase() const171 void* MemoryHeapBase::getBase() const {
172 return mBase;
173 }
174
getSize() const175 size_t MemoryHeapBase::getSize() const {
176 return mSize;
177 }
178
getFlags() const179 uint32_t MemoryHeapBase::getFlags() const {
180 return mFlags;
181 }
182
getDevice() const183 const char* MemoryHeapBase::getDevice() const {
184 return mDevice;
185 }
186
getOffset() const187 uint32_t MemoryHeapBase::getOffset() const {
188 return mOffset;
189 }
190
191 // ---------------------------------------------------------------------------
192 }; // namespace android
193