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 #include <limits.h> 18 #include <errno.h> 19 #include <pthread.h> 20 #include <unistd.h> 21 #include <string.h> 22 23 #include <sys/mman.h> 24 #include <sys/stat.h> 25 #include <sys/types.h> 26 27 #include <cutils/log.h> 28 #include <cutils/atomic.h> 29 30 #include <hardware/hardware.h> 31 #include <hardware/gralloc.h> 32 33 #include "gralloc_priv.h" 34 35 36 /* desktop Linux needs a little help with gettid() */ 37 #if defined(ARCH_X86) && !defined(HAVE_ANDROID_OS) 38 #define __KERNEL__ 39 # include <linux/unistd.h> 40 pid_t gettid() { return syscall(__NR_gettid);} 41 #undef __KERNEL__ 42 #endif 43 44 /*****************************************************************************/ 45 46 static int gralloc_map(gralloc_module_t const* module, 47 buffer_handle_t handle, 48 void** vaddr) 49 { 50 private_handle_t* hnd = (private_handle_t*)handle; 51 if (!(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) { 52 size_t size = hnd->size; 53 void* mappedAddress = mmap(0, size, 54 PROT_READ|PROT_WRITE, MAP_SHARED, hnd->fd, 0); 55 if (mappedAddress == MAP_FAILED) { 56 LOGE("Could not mmap %s", strerror(errno)); 57 return -errno; 58 } 59 hnd->base = intptr_t(mappedAddress) + hnd->offset; 60 //LOGD("gralloc_map() succeeded fd=%d, off=%d, size=%d, vaddr=%p", 61 // hnd->fd, hnd->offset, hnd->size, mappedAddress); 62 } 63 *vaddr = (void*)hnd->base; 64 return 0; 65 } 66 67 static int gralloc_unmap(gralloc_module_t const* module, 68 buffer_handle_t handle) 69 { 70 private_handle_t* hnd = (private_handle_t*)handle; 71 if (!(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) { 72 void* base = (void*)hnd->base; 73 size_t size = hnd->size; 74 //LOGD("unmapping from %p, size=%d", base, size); 75 if (munmap(base, size) < 0) { 76 LOGE("Could not unmap %s", strerror(errno)); 77 } 78 } 79 hnd->base = 0; 80 return 0; 81 } 82 83 /*****************************************************************************/ 84 85 static pthread_mutex_t sMapLock = PTHREAD_MUTEX_INITIALIZER; 86 87 /*****************************************************************************/ 88 89 int gralloc_register_buffer(gralloc_module_t const* module, 90 buffer_handle_t handle) 91 { 92 if (private_handle_t::validate(handle) < 0) 93 return -EINVAL; 94 95 // if this handle was created in this process, then we keep it as is. 96 int err = 0; 97 private_handle_t* hnd = (private_handle_t*)handle; 98 if (hnd->pid != getpid()) { 99 void *vaddr; 100 err = gralloc_map(module, handle, &vaddr); 101 } 102 return err; 103 } 104 105 int gralloc_unregister_buffer(gralloc_module_t const* module, 106 buffer_handle_t handle) 107 { 108 if (private_handle_t::validate(handle) < 0) 109 return -EINVAL; 110 111 // never unmap buffers that were created in this process 112 private_handle_t* hnd = (private_handle_t*)handle; 113 if (hnd->pid != getpid()) { 114 if (hnd->base) { 115 gralloc_unmap(module, handle); 116 } 117 } 118 return 0; 119 } 120 121 int mapBuffer(gralloc_module_t const* module, 122 private_handle_t* hnd) 123 { 124 void* vaddr; 125 return gralloc_map(module, hnd, &vaddr); 126 } 127 128 int terminateBuffer(gralloc_module_t const* module, 129 private_handle_t* hnd) 130 { 131 if (hnd->base) { 132 // this buffer was mapped, unmap it now 133 gralloc_unmap(module, hnd); 134 } 135 136 return 0; 137 } 138 139 int gralloc_lock(gralloc_module_t const* module, 140 buffer_handle_t handle, int usage, 141 int l, int t, int w, int h, 142 void** vaddr) 143 { 144 // this is called when a buffer is being locked for software 145 // access. in thin implementation we have nothing to do since 146 // not synchronization with the h/w is needed. 147 // typically this is used to wait for the h/w to finish with 148 // this buffer if relevant. the data cache may need to be 149 // flushed or invalidated depending on the usage bits and the 150 // hardware. 151 152 if (private_handle_t::validate(handle) < 0) 153 return -EINVAL; 154 155 private_handle_t* hnd = (private_handle_t*)handle; 156 *vaddr = (void*)hnd->base; 157 return 0; 158 } 159 160 int gralloc_unlock(gralloc_module_t const* module, 161 buffer_handle_t handle) 162 { 163 // we're done with a software buffer. nothing to do in this 164 // implementation. typically this is used to flush the data cache. 165 166 if (private_handle_t::validate(handle) < 0) 167 return -EINVAL; 168 return 0; 169 } 170