reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame^] | 1 | #include "SkImageRef_ashmem.h" |
| 2 | #include "SkImageDecoder.h" |
| 3 | #include "SkThread.h" |
| 4 | |
| 5 | #include <sys/mman.h> |
| 6 | #include <unistd.h> |
| 7 | #include <cutils/ashmem.h> |
| 8 | |
| 9 | //#define TRACE_ASH_PURGE // just trace purges |
| 10 | |
| 11 | #ifdef DUMP_IMAGEREF_LIFECYCLE |
| 12 | #define DUMP_ASHMEM_LIFECYCLE |
| 13 | #else |
| 14 | // #define DUMP_ASHMEM_LIFECYCLE |
| 15 | #endif |
| 16 | |
| 17 | // ashmem likes lengths on page boundaries |
| 18 | static size_t roundToPageSize(size_t size) { |
| 19 | const size_t mask = getpagesize() - 1; |
| 20 | size_t newsize = (size + mask) & ~mask; |
| 21 | // SkDebugf("---- oldsize %d newsize %d\n", size, newsize); |
| 22 | return newsize; |
| 23 | } |
| 24 | |
| 25 | SkImageRef_ashmem::SkImageRef_ashmem(SkStream* stream, |
| 26 | SkBitmap::Config config, |
| 27 | int sampleSize) |
| 28 | : SkImageRef(stream, config, sampleSize) { |
| 29 | |
| 30 | fRec.fFD = -1; |
| 31 | fRec.fAddr = NULL; |
| 32 | fRec.fSize = 0; |
| 33 | fRec.fPinned = false; |
| 34 | |
| 35 | fCT = NULL; |
| 36 | } |
| 37 | |
| 38 | SkImageRef_ashmem::~SkImageRef_ashmem() { |
| 39 | fCT->safeUnref(); |
| 40 | this->closeFD(); |
| 41 | } |
| 42 | |
| 43 | void SkImageRef_ashmem::closeFD() { |
| 44 | if (-1 != fRec.fFD) { |
| 45 | #ifdef DUMP_ASHMEM_LIFECYCLE |
| 46 | SkDebugf("=== ashmem close %d\n", fRec.fFD); |
| 47 | #endif |
| 48 | SkASSERT(fRec.fAddr); |
| 49 | SkASSERT(fRec.fSize); |
| 50 | munmap(fRec.fAddr, fRec.fSize); |
| 51 | close(fRec.fFD); |
| 52 | fRec.fFD = -1; |
| 53 | } |
| 54 | } |
| 55 | |
| 56 | /////////////////////////////////////////////////////////////////////////////// |
| 57 | |
| 58 | class AshmemAllocator : public SkBitmap::Allocator { |
| 59 | public: |
| 60 | AshmemAllocator(SkAshmemRec* rec, const char name[]) |
| 61 | : fRec(rec), fName(name) {} |
| 62 | |
| 63 | virtual bool allocPixelRef(SkBitmap* bm, SkColorTable* ct) { |
| 64 | const size_t size = roundToPageSize(bm->getSize()); |
| 65 | int fd = fRec->fFD; |
| 66 | void* addr = fRec->fAddr; |
| 67 | |
| 68 | SkASSERT(!fRec->fPinned); |
| 69 | |
| 70 | if (-1 == fd) { |
| 71 | SkASSERT(NULL == addr); |
| 72 | SkASSERT(0 == fRec->fSize); |
| 73 | |
| 74 | fd = ashmem_create_region(fName, size); |
| 75 | #ifdef DUMP_ASHMEM_LIFECYCLE |
| 76 | SkDebugf("=== ashmem_create_region %s size=%d fd=%d\n", fName, size, fd); |
| 77 | #endif |
| 78 | if (-1 == fd) { |
| 79 | SkDebugf("------- imageref_ashmem create failed <%s> %d\n", |
| 80 | fName, size); |
| 81 | return false; |
| 82 | } |
| 83 | |
| 84 | int err = ashmem_set_prot_region(fd, PROT_READ | PROT_WRITE); |
| 85 | if (err) { |
| 86 | SkDebugf("------ ashmem_set_prot_region(%d) failed %d %d\n", |
| 87 | fd, err, errno); |
| 88 | return false; |
| 89 | } |
| 90 | |
| 91 | addr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); |
| 92 | if (-1 == (long)addr) { |
| 93 | SkDebugf("---------- mmap failed for imageref_ashmem size=%d err=%d\n", |
| 94 | size, errno); |
| 95 | return false; |
| 96 | } |
| 97 | |
| 98 | fRec->fFD = fd; |
| 99 | fRec->fAddr = addr; |
| 100 | fRec->fSize = size; |
| 101 | } else { |
| 102 | SkASSERT(addr); |
| 103 | SkASSERT(size == fRec->fSize); |
| 104 | (void)ashmem_pin_region(fd, 0, 0); |
| 105 | } |
| 106 | |
| 107 | bm->setPixels(addr, ct); |
| 108 | fRec->fPinned = true; |
| 109 | return true; |
| 110 | } |
| 111 | |
| 112 | private: |
| 113 | // we just point to our caller's memory, these are not copies |
| 114 | SkAshmemRec* fRec; |
| 115 | const char* fName; |
| 116 | }; |
| 117 | |
| 118 | bool SkImageRef_ashmem::onDecode(SkImageDecoder* codec, SkStream* stream, |
| 119 | SkBitmap* bitmap, SkBitmap::Config config, |
| 120 | SkImageDecoder::Mode mode) { |
| 121 | |
| 122 | if (SkImageDecoder::kDecodeBounds_Mode == mode) { |
| 123 | return this->INHERITED::onDecode(codec, stream, bitmap, config, mode); |
| 124 | } |
| 125 | |
| 126 | AshmemAllocator alloc(&fRec, this->getURI()); |
| 127 | |
| 128 | codec->setAllocator(&alloc); |
| 129 | bool success = this->INHERITED::onDecode(codec, stream, bitmap, config, |
| 130 | mode); |
| 131 | // remove the allocator, since its on the stack |
| 132 | codec->setAllocator(NULL); |
| 133 | |
| 134 | if (success) { |
| 135 | // remember the colortable (if any) |
| 136 | SkRefCnt_SafeAssign(fCT, bitmap->getColorTable()); |
| 137 | return true; |
| 138 | } else { |
| 139 | if (fRec.fPinned) { |
| 140 | ashmem_unpin_region(fRec.fFD, 0, 0); |
| 141 | fRec.fPinned = false; |
| 142 | } |
| 143 | this->closeFD(); |
| 144 | return false; |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | void* SkImageRef_ashmem::onLockPixels(SkColorTable** ct) { |
| 149 | SkASSERT(fBitmap.getPixels() == NULL); |
| 150 | SkASSERT(fBitmap.getColorTable() == NULL); |
| 151 | |
| 152 | // fast case: check if we can just pin and get the cached data |
| 153 | if (-1 != fRec.fFD) { |
| 154 | SkASSERT(fRec.fAddr); |
| 155 | SkASSERT(!fRec.fPinned); |
| 156 | int pin = ashmem_pin_region(fRec.fFD, 0, 0); |
| 157 | |
| 158 | if (ASHMEM_NOT_PURGED == pin) { // yea, fast case! |
| 159 | fBitmap.setPixels(fRec.fAddr, fCT); |
| 160 | fRec.fPinned = true; |
| 161 | } else if (ASHMEM_WAS_PURGED == pin) { |
| 162 | ashmem_unpin_region(fRec.fFD, 0, 0); |
| 163 | // let go of our colortable if we lost the pixels. Well get it back |
| 164 | // again when we re-decode |
| 165 | if (fCT) { |
| 166 | fCT->unref(); |
| 167 | fCT = NULL; |
| 168 | } |
| 169 | #if defined(DUMP_ASHMEM_LIFECYCLE) || defined(TRACE_ASH_PURGE) |
| 170 | SkDebugf("===== ashmem purged %d\n", fBitmap.getSize()); |
| 171 | #endif |
| 172 | } else { |
| 173 | SkDebugf("===== ashmem pin_region(%d) returned %d, treating as error %d\n", |
| 174 | fRec.fFD, pin, errno); |
| 175 | // return null result for failure |
| 176 | if (ct) { |
| 177 | *ct = NULL; |
| 178 | } |
| 179 | return NULL; |
| 180 | } |
| 181 | } else { |
| 182 | // no FD, will create an ashmem region in allocator |
| 183 | } |
| 184 | |
| 185 | return this->INHERITED::onLockPixels(ct); |
| 186 | } |
| 187 | |
| 188 | void SkImageRef_ashmem::onUnlockPixels() { |
| 189 | this->INHERITED::onUnlockPixels(); |
| 190 | |
| 191 | if (-1 != fRec.fFD) { |
| 192 | SkASSERT(fRec.fAddr); |
| 193 | SkASSERT(fRec.fPinned); |
| 194 | |
| 195 | ashmem_unpin_region(fRec.fFD, 0, 0); |
| 196 | fRec.fPinned = false; |
| 197 | } |
| 198 | |
| 199 | // we clear this with or without an error, since we've either closed or |
| 200 | // unpinned the region |
| 201 | fBitmap.setPixels(NULL, NULL); |
| 202 | } |
| 203 | |