1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/src/images/SkImageRef_ashmem.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,230 @@
1.4 +/*
1.5 + * Copyright 2011 Google Inc.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +#include "SkImageRef_ashmem.h"
1.12 +#include "SkImageDecoder.h"
1.13 +#include "SkReadBuffer.h"
1.14 +#include "SkWriteBuffer.h"
1.15 +#include "SkThread.h"
1.16 +
1.17 +#include "android/ashmem.h"
1.18 +
1.19 +#include <sys/mman.h>
1.20 +#include <unistd.h>
1.21 +
1.22 +//#define TRACE_ASH_PURGE // just trace purges
1.23 +
1.24 +#ifdef DUMP_IMAGEREF_LIFECYCLE
1.25 + #define DUMP_ASHMEM_LIFECYCLE
1.26 +#else
1.27 +// #define DUMP_ASHMEM_LIFECYCLE
1.28 +#endif
1.29 +
1.30 +// ashmem likes lengths on page boundaries
1.31 +static size_t roundToPageSize(size_t size) {
1.32 + const size_t mask = getpagesize() - 1;
1.33 + size_t newsize = (size + mask) & ~mask;
1.34 +// SkDebugf("---- oldsize %d newsize %d\n", size, newsize);
1.35 + return newsize;
1.36 +}
1.37 +
1.38 +SkImageRef_ashmem::SkImageRef_ashmem(const SkImageInfo& info,
1.39 + SkStreamRewindable* stream,
1.40 + int sampleSize)
1.41 + : SkImageRef(info, stream, sampleSize)
1.42 +{
1.43 + fRec.fFD = -1;
1.44 + fRec.fAddr = NULL;
1.45 + fRec.fSize = 0;
1.46 + fRec.fPinned = false;
1.47 +
1.48 + fCT = NULL;
1.49 +}
1.50 +
1.51 +SkImageRef_ashmem::~SkImageRef_ashmem() {
1.52 + SkSafeUnref(fCT);
1.53 + this->closeFD();
1.54 +}
1.55 +
1.56 +void SkImageRef_ashmem::closeFD() {
1.57 + if (-1 != fRec.fFD) {
1.58 +#ifdef DUMP_ASHMEM_LIFECYCLE
1.59 + SkDebugf("=== ashmem close %d\n", fRec.fFD);
1.60 +#endif
1.61 + SkASSERT(fRec.fAddr);
1.62 + SkASSERT(fRec.fSize);
1.63 + munmap(fRec.fAddr, fRec.fSize);
1.64 + close(fRec.fFD);
1.65 + fRec.fFD = -1;
1.66 + }
1.67 +}
1.68 +
1.69 +///////////////////////////////////////////////////////////////////////////////
1.70 +
1.71 +class AshmemAllocator : public SkBitmap::Allocator {
1.72 +public:
1.73 + AshmemAllocator(SkAshmemRec* rec, const char name[])
1.74 + : fRec(rec), fName(name) {}
1.75 +
1.76 + virtual bool allocPixelRef(SkBitmap* bm, SkColorTable* ct) {
1.77 + const size_t size = roundToPageSize(bm->getSize());
1.78 + int fd = fRec->fFD;
1.79 + void* addr = fRec->fAddr;
1.80 +
1.81 + SkASSERT(!fRec->fPinned);
1.82 +
1.83 + if (-1 == fd) {
1.84 + SkASSERT(NULL == addr);
1.85 + SkASSERT(0 == fRec->fSize);
1.86 +
1.87 + fd = ashmem_create_region(fName, size);
1.88 +#ifdef DUMP_ASHMEM_LIFECYCLE
1.89 + SkDebugf("=== ashmem_create_region %s size=%d fd=%d\n", fName, size, fd);
1.90 +#endif
1.91 + if (-1 == fd) {
1.92 + SkDebugf("------- imageref_ashmem create failed <%s> %d\n",
1.93 + fName, size);
1.94 + return false;
1.95 + }
1.96 +
1.97 + int err = ashmem_set_prot_region(fd, PROT_READ | PROT_WRITE);
1.98 + if (err) {
1.99 + SkDebugf("------ ashmem_set_prot_region(%d) failed %d\n",
1.100 + fd, err);
1.101 + close(fd);
1.102 + return false;
1.103 + }
1.104 +
1.105 + addr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
1.106 + if (-1 == (long)addr) {
1.107 + SkDebugf("---------- mmap failed for imageref_ashmem size=%d\n",
1.108 + size);
1.109 + close(fd);
1.110 + return false;
1.111 + }
1.112 +
1.113 + fRec->fFD = fd;
1.114 + fRec->fAddr = addr;
1.115 + fRec->fSize = size;
1.116 + } else {
1.117 + SkASSERT(addr);
1.118 + SkASSERT(size == fRec->fSize);
1.119 + (void)ashmem_pin_region(fd, 0, 0);
1.120 + }
1.121 +
1.122 + bm->setPixels(addr, ct);
1.123 + fRec->fPinned = true;
1.124 + return true;
1.125 + }
1.126 +
1.127 +private:
1.128 + // we just point to our caller's memory, these are not copies
1.129 + SkAshmemRec* fRec;
1.130 + const char* fName;
1.131 +};
1.132 +
1.133 +bool SkImageRef_ashmem::onDecode(SkImageDecoder* codec, SkStreamRewindable* stream,
1.134 + SkBitmap* bitmap, SkBitmap::Config config,
1.135 + SkImageDecoder::Mode mode) {
1.136 +
1.137 + if (SkImageDecoder::kDecodeBounds_Mode == mode) {
1.138 + return this->INHERITED::onDecode(codec, stream, bitmap, config, mode);
1.139 + }
1.140 +
1.141 + // Ashmem memory is guaranteed to be initialized to 0.
1.142 + codec->setSkipWritingZeroes(true);
1.143 +
1.144 + AshmemAllocator alloc(&fRec, this->getURI());
1.145 +
1.146 + codec->setAllocator(&alloc);
1.147 + bool success = this->INHERITED::onDecode(codec, stream, bitmap, config,
1.148 + mode);
1.149 + // remove the allocator, since its on the stack
1.150 + codec->setAllocator(NULL);
1.151 +
1.152 + if (success) {
1.153 + // remember the colortable (if any)
1.154 + SkRefCnt_SafeAssign(fCT, bitmap->getColorTable());
1.155 + return true;
1.156 + } else {
1.157 + if (fRec.fPinned) {
1.158 + ashmem_unpin_region(fRec.fFD, 0, 0);
1.159 + fRec.fPinned = false;
1.160 + }
1.161 + this->closeFD();
1.162 + return false;
1.163 + }
1.164 +}
1.165 +
1.166 +bool SkImageRef_ashmem::onNewLockPixels(LockRec* rec) {
1.167 + SkASSERT(fBitmap.getPixels() == NULL);
1.168 + SkASSERT(fBitmap.getColorTable() == NULL);
1.169 +
1.170 + // fast case: check if we can just pin and get the cached data
1.171 + if (-1 != fRec.fFD) {
1.172 + SkASSERT(fRec.fAddr);
1.173 + SkASSERT(!fRec.fPinned);
1.174 + int pin = ashmem_pin_region(fRec.fFD, 0, 0);
1.175 +
1.176 + if (ASHMEM_NOT_PURGED == pin) { // yea, fast case!
1.177 + fBitmap.setPixels(fRec.fAddr, fCT);
1.178 + fRec.fPinned = true;
1.179 + } else if (ASHMEM_WAS_PURGED == pin) {
1.180 + ashmem_unpin_region(fRec.fFD, 0, 0);
1.181 + // let go of our colortable if we lost the pixels. Well get it back
1.182 + // again when we re-decode
1.183 + if (fCT) {
1.184 + fCT->unref();
1.185 + fCT = NULL;
1.186 + }
1.187 +#if defined(DUMP_ASHMEM_LIFECYCLE) || defined(TRACE_ASH_PURGE)
1.188 + SkDebugf("===== ashmem purged %d\n", fBitmap.getSize());
1.189 +#endif
1.190 + } else {
1.191 + SkDebugf("===== ashmem pin_region(%d) returned %d\n", fRec.fFD, pin);
1.192 + return false;
1.193 + }
1.194 + } else {
1.195 + // no FD, will create an ashmem region in allocator
1.196 + }
1.197 +
1.198 + return this->INHERITED::onNewLockPixels(rec);
1.199 +}
1.200 +
1.201 +void SkImageRef_ashmem::onUnlockPixels() {
1.202 + this->INHERITED::onUnlockPixels();
1.203 +
1.204 + if (-1 != fRec.fFD) {
1.205 + SkASSERT(fRec.fAddr);
1.206 + SkASSERT(fRec.fPinned);
1.207 +
1.208 + ashmem_unpin_region(fRec.fFD, 0, 0);
1.209 + fRec.fPinned = false;
1.210 + }
1.211 +
1.212 + // we clear this with or without an error, since we've either closed or
1.213 + // unpinned the region
1.214 + fBitmap.setPixels(NULL, NULL);
1.215 +}
1.216 +
1.217 +void SkImageRef_ashmem::flatten(SkWriteBuffer& buffer) const {
1.218 + this->INHERITED::flatten(buffer);
1.219 + buffer.writeString(getURI());
1.220 +}
1.221 +
1.222 +SkImageRef_ashmem::SkImageRef_ashmem(SkReadBuffer& buffer)
1.223 + : INHERITED(buffer) {
1.224 + fRec.fFD = -1;
1.225 + fRec.fAddr = NULL;
1.226 + fRec.fSize = 0;
1.227 + fRec.fPinned = false;
1.228 + fCT = NULL;
1.229 +
1.230 + SkString uri;
1.231 + buffer.readString(&uri);
1.232 + this->setURI(uri);
1.233 +}
