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 namespace android {
35
36 // ---------------------------------------------------------------------------
37
MemoryHeapBase()38 MemoryHeapBase::MemoryHeapBase()
39 : mFD(-1), mSize(0), mBase(MAP_FAILED),
40 mDevice(NULL), mNeedUnmap(false), mOffset(0)
41 {
42 }
43
MemoryHeapBase(size_t size,uint32_t flags,char const * name)44 MemoryHeapBase::MemoryHeapBase(size_t size, uint32_t flags, char const * name)
45 : mFD(-1), mSize(0), mBase(MAP_FAILED), mFlags(flags),
46 mDevice(0), mNeedUnmap(false), mOffset(0)
47 {
48 const size_t pagesize = getpagesize();
49 size = ((size + pagesize-1) & ~(pagesize-1));
50 int fd = ashmem_create_region(name == NULL ? "MemoryHeapBase" : name, size);
51 ALOGE_IF(fd<0, "error creating ashmem region: %s", strerror(errno));
52 if (fd >= 0) {
53 if (mapfd(fd, size) == NO_ERROR) {
54 if (flags & READ_ONLY) {
55 ashmem_set_prot_region(fd, PROT_READ);
56 }
57 }
58 }
59 }
60
MemoryHeapBase(const char * device,size_t size,uint32_t flags)61 MemoryHeapBase::MemoryHeapBase(const char* device, size_t size, uint32_t flags)
62 : mFD(-1), mSize(0), mBase(MAP_FAILED), mFlags(flags),
63 mDevice(0), mNeedUnmap(false), mOffset(0)
64 {
65 int open_flags = O_RDWR;
66 if (flags & NO_CACHING)
67 open_flags |= O_SYNC;
68
69 int fd = open(device, open_flags);
70 ALOGE_IF(fd<0, "error opening %s: %s", device, strerror(errno));
71 if (fd >= 0) {
72 const size_t pagesize = getpagesize();
73 size = ((size + pagesize-1) & ~(pagesize-1));
74 if (mapfd(fd, size) == NO_ERROR) {
75 mDevice = device;
76 }
77 }
78 }
79
MemoryHeapBase(int fd,size_t size,uint32_t flags,uint32_t offset)80 MemoryHeapBase::MemoryHeapBase(int fd, size_t size, uint32_t flags, uint32_t offset)
81 : mFD(-1), mSize(0), mBase(MAP_FAILED), mFlags(flags),
82 mDevice(0), mNeedUnmap(false), mOffset(0)
83 {
84 const size_t pagesize = getpagesize();
85 size = ((size + pagesize-1) & ~(pagesize-1));
86 mapfd(dup(fd), size, offset);
87 }
88
init(int fd,void * base,int size,int flags,const char * device)89 status_t MemoryHeapBase::init(int fd, void *base, int size, int flags, const char* device)
90 {
91 if (mFD != -1) {
92 return INVALID_OPERATION;
93 }
94 mFD = fd;
95 mBase = base;
96 mSize = size;
97 mFlags = flags;
98 mDevice = device;
99 return NO_ERROR;
100 }
101
mapfd(int fd,size_t size,uint32_t offset)102 status_t MemoryHeapBase::mapfd(int fd, size_t size, uint32_t offset)
103 {
104 if (size == 0) {
105 // try to figure out the size automatically
106 struct stat sb;
107 if (fstat(fd, &sb) == 0)
108 size = sb.st_size;
109 // if it didn't work, let mmap() fail.
110 }
111
112 if ((mFlags & DONT_MAP_LOCALLY) == 0) {
113 void* base = (uint8_t*)mmap(0, size,
114 PROT_READ|PROT_WRITE, MAP_SHARED, fd, offset);
115 if (base == MAP_FAILED) {
116 ALOGE("mmap(fd=%d, size=%u) failed (%s)",
117 fd, uint32_t(size), strerror(errno));
118 close(fd);
119 return -errno;
120 }
121 //ALOGD("mmap(fd=%d, base=%p, size=%lu)", fd, base, size);
122 mBase = base;
123 mNeedUnmap = true;
124 } else {
125 mBase = 0; // not MAP_FAILED
126 mNeedUnmap = false;
127 }
128 mFD = fd;
129 mSize = size;
130 mOffset = offset;
131 return NO_ERROR;
132 }
133
~MemoryHeapBase()134 MemoryHeapBase::~MemoryHeapBase()
135 {
136 dispose();
137 }
138
dispose()139 void MemoryHeapBase::dispose()
140 {
141 int fd = android_atomic_or(-1, &mFD);
142 if (fd >= 0) {
143 if (mNeedUnmap) {
144 //ALOGD("munmap(fd=%d, base=%p, size=%lu)", fd, mBase, mSize);
145 munmap(mBase, mSize);
146 }
147 mBase = 0;
148 mSize = 0;
149 close(fd);
150 }
151 }
152
getHeapID() const153 int MemoryHeapBase::getHeapID() const {
154 return mFD;
155 }
156
getBase() const157 void* MemoryHeapBase::getBase() const {
158 return mBase;
159 }
160
getSize() const161 size_t MemoryHeapBase::getSize() const {
162 return mSize;
163 }
164
getFlags() const165 uint32_t MemoryHeapBase::getFlags() const {
166 return mFlags;
167 }
168
getDevice() const169 const char* MemoryHeapBase::getDevice() const {
170 return mDevice;
171 }
172
getOffset() const173 uint32_t MemoryHeapBase::getOffset() const {
174 return mOffset;
175 }
176
177 // ---------------------------------------------------------------------------
178 }; // namespace android
179