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      1 /*
      2  * Copyright (C) 2011 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 "image_space.h"
     18 
     19 #include <dirent.h>
     20 #include <sys/types.h>
     21 
     22 #include <random>
     23 
     24 #include "base/stl_util.h"
     25 #include "base/unix_file/fd_file.h"
     26 #include "base/scoped_flock.h"
     27 #include "gc/accounting/space_bitmap-inl.h"
     28 #include "mirror/art_method.h"
     29 #include "mirror/class-inl.h"
     30 #include "mirror/object-inl.h"
     31 #include "oat_file.h"
     32 #include "os.h"
     33 #include "space-inl.h"
     34 #include "utils.h"
     35 
     36 namespace art {
     37 namespace gc {
     38 namespace space {
     39 
     40 Atomic<uint32_t> ImageSpace::bitmap_index_(0);
     41 
     42 ImageSpace::ImageSpace(const std::string& image_filename, const char* image_location,
     43                        MemMap* mem_map, accounting::ContinuousSpaceBitmap* live_bitmap)
     44     : MemMapSpace(image_filename, mem_map, mem_map->Begin(), mem_map->End(), mem_map->End(),
     45                   kGcRetentionPolicyNeverCollect),
     46       image_location_(image_location) {
     47   DCHECK(live_bitmap != nullptr);
     48   live_bitmap_.reset(live_bitmap);
     49 }
     50 
     51 static int32_t ChooseRelocationOffsetDelta(int32_t min_delta, int32_t max_delta) {
     52   CHECK_ALIGNED(min_delta, kPageSize);
     53   CHECK_ALIGNED(max_delta, kPageSize);
     54   CHECK_LT(min_delta, max_delta);
     55 
     56   std::default_random_engine generator;
     57   generator.seed(NanoTime() * getpid());
     58   std::uniform_int_distribution<int32_t> distribution(min_delta, max_delta);
     59   int32_t r = distribution(generator);
     60   if (r % 2 == 0) {
     61     r = RoundUp(r, kPageSize);
     62   } else {
     63     r = RoundDown(r, kPageSize);
     64   }
     65   CHECK_LE(min_delta, r);
     66   CHECK_GE(max_delta, r);
     67   CHECK_ALIGNED(r, kPageSize);
     68   return r;
     69 }
     70 
     71 // We are relocating or generating the core image. We should get rid of everything. It is all
     72 // out-of-date. We also don't really care if this fails since it is just a convienence.
     73 // Adapted from prune_dex_cache(const char* subdir) in frameworks/native/cmds/installd/commands.c
     74 // Note this should only be used during first boot.
     75 static void RealPruneDexCache(const std::string& cache_dir_path);
     76 static void PruneDexCache(InstructionSet isa) {
     77   CHECK_NE(isa, kNone);
     78   // Prune the base /data/dalvik-cache
     79   RealPruneDexCache(GetDalvikCacheOrDie(".", false));
     80   // prune /data/dalvik-cache/<isa>
     81   RealPruneDexCache(GetDalvikCacheOrDie(GetInstructionSetString(isa), false));
     82 }
     83 static void RealPruneDexCache(const std::string& cache_dir_path) {
     84   if (!OS::DirectoryExists(cache_dir_path.c_str())) {
     85     return;
     86   }
     87   DIR* cache_dir = opendir(cache_dir_path.c_str());
     88   if (cache_dir == nullptr) {
     89     PLOG(WARNING) << "Unable to open " << cache_dir_path << " to delete it's contents";
     90     return;
     91   }
     92 
     93   for (struct dirent* de = readdir(cache_dir); de != nullptr; de = readdir(cache_dir)) {
     94     const char* name = de->d_name;
     95     if (strcmp(name, ".") == 0 || strcmp(name, "..") == 0) {
     96       continue;
     97     }
     98     // We only want to delete regular files.
     99     if (de->d_type != DT_REG) {
    100       if (de->d_type != DT_DIR) {
    101         // We do expect some directories (namely the <isa> for pruning the base dalvik-cache).
    102         LOG(WARNING) << "Unexpected file type of " << std::hex << de->d_type << " encountered.";
    103       }
    104       continue;
    105     }
    106     std::string cache_file(cache_dir_path);
    107     cache_file += '/';
    108     cache_file += name;
    109     if (TEMP_FAILURE_RETRY(unlink(cache_file.c_str())) != 0) {
    110       PLOG(ERROR) << "Unable to unlink " << cache_file;
    111       continue;
    112     }
    113   }
    114   CHECK_EQ(0, TEMP_FAILURE_RETRY(closedir(cache_dir))) << "Unable to close directory.";
    115 }
    116 
    117 static bool GenerateImage(const std::string& image_filename, InstructionSet image_isa,
    118                           std::string* error_msg) {
    119   const std::string boot_class_path_string(Runtime::Current()->GetBootClassPathString());
    120   std::vector<std::string> boot_class_path;
    121   Split(boot_class_path_string, ':', boot_class_path);
    122   if (boot_class_path.empty()) {
    123     *error_msg = "Failed to generate image because no boot class path specified";
    124     return false;
    125   }
    126   // We should clean up so we are more likely to have room for the image.
    127   if (Runtime::Current()->IsZygote()) {
    128     LOG(INFO) << "Pruning dalvik-cache since we are generating an image and will need to recompile";
    129     PruneDexCache(image_isa);
    130   }
    131 
    132   std::vector<std::string> arg_vector;
    133 
    134   std::string dex2oat(Runtime::Current()->GetCompilerExecutable());
    135   arg_vector.push_back(dex2oat);
    136 
    137   std::string image_option_string("--image=");
    138   image_option_string += image_filename;
    139   arg_vector.push_back(image_option_string);
    140 
    141   for (size_t i = 0; i < boot_class_path.size(); i++) {
    142     arg_vector.push_back(std::string("--dex-file=") + boot_class_path[i]);
    143   }
    144 
    145   std::string oat_file_option_string("--oat-file=");
    146   oat_file_option_string += ImageHeader::GetOatLocationFromImageLocation(image_filename);
    147   arg_vector.push_back(oat_file_option_string);
    148 
    149   Runtime::Current()->AddCurrentRuntimeFeaturesAsDex2OatArguments(&arg_vector);
    150   CHECK_EQ(image_isa, kRuntimeISA)
    151       << "We should always be generating an image for the current isa.";
    152 
    153   int32_t base_offset = ChooseRelocationOffsetDelta(ART_BASE_ADDRESS_MIN_DELTA,
    154                                                     ART_BASE_ADDRESS_MAX_DELTA);
    155   LOG(INFO) << "Using an offset of 0x" << std::hex << base_offset << " from default "
    156             << "art base address of 0x" << std::hex << ART_BASE_ADDRESS;
    157   arg_vector.push_back(StringPrintf("--base=0x%x", ART_BASE_ADDRESS + base_offset));
    158 
    159   if (!kIsTargetBuild) {
    160     arg_vector.push_back("--host");
    161   }
    162 
    163   const std::vector<std::string>& compiler_options = Runtime::Current()->GetImageCompilerOptions();
    164   for (size_t i = 0; i < compiler_options.size(); ++i) {
    165     arg_vector.push_back(compiler_options[i].c_str());
    166   }
    167 
    168   std::string command_line(Join(arg_vector, ' '));
    169   LOG(INFO) << "GenerateImage: " << command_line;
    170   return Exec(arg_vector, error_msg);
    171 }
    172 
    173 bool ImageSpace::FindImageFilename(const char* image_location,
    174                                    const InstructionSet image_isa,
    175                                    std::string* system_filename,
    176                                    bool* has_system,
    177                                    std::string* cache_filename,
    178                                    bool* dalvik_cache_exists,
    179                                    bool* has_cache,
    180                                    bool* is_global_cache) {
    181   *has_system = false;
    182   *has_cache = false;
    183   // image_location = /system/framework/boot.art
    184   // system_image_location = /system/framework/<image_isa>/boot.art
    185   std::string system_image_filename(GetSystemImageFilename(image_location, image_isa));
    186   if (OS::FileExists(system_image_filename.c_str())) {
    187     *system_filename = system_image_filename;
    188     *has_system = true;
    189   }
    190 
    191   bool have_android_data = false;
    192   *dalvik_cache_exists = false;
    193   std::string dalvik_cache;
    194   GetDalvikCache(GetInstructionSetString(image_isa), true, &dalvik_cache,
    195                  &have_android_data, dalvik_cache_exists, is_global_cache);
    196 
    197   if (have_android_data && *dalvik_cache_exists) {
    198     // Always set output location even if it does not exist,
    199     // so that the caller knows where to create the image.
    200     //
    201     // image_location = /system/framework/boot.art
    202     // *image_filename = /data/dalvik-cache/<image_isa>/boot.art
    203     std::string error_msg;
    204     if (!GetDalvikCacheFilename(image_location, dalvik_cache.c_str(), cache_filename, &error_msg)) {
    205       LOG(WARNING) << error_msg;
    206       return *has_system;
    207     }
    208     *has_cache = OS::FileExists(cache_filename->c_str());
    209   }
    210   return *has_system || *has_cache;
    211 }
    212 
    213 static bool ReadSpecificImageHeader(const char* filename, ImageHeader* image_header) {
    214     std::unique_ptr<File> image_file(OS::OpenFileForReading(filename));
    215     if (image_file.get() == nullptr) {
    216       return false;
    217     }
    218     const bool success = image_file->ReadFully(image_header, sizeof(ImageHeader));
    219     if (!success || !image_header->IsValid()) {
    220       return false;
    221     }
    222     return true;
    223 }
    224 
    225 // Relocate the image at image_location to dest_filename and relocate it by a random amount.
    226 static bool RelocateImage(const char* image_location, const char* dest_filename,
    227                                InstructionSet isa, std::string* error_msg) {
    228   // We should clean up so we are more likely to have room for the image.
    229   if (Runtime::Current()->IsZygote()) {
    230     LOG(INFO) << "Pruning dalvik-cache since we are relocating an image and will need to recompile";
    231     PruneDexCache(isa);
    232   }
    233 
    234   std::string patchoat(Runtime::Current()->GetPatchoatExecutable());
    235 
    236   std::string input_image_location_arg("--input-image-location=");
    237   input_image_location_arg += image_location;
    238 
    239   std::string output_image_filename_arg("--output-image-file=");
    240   output_image_filename_arg += dest_filename;
    241 
    242   std::string input_oat_location_arg("--input-oat-location=");
    243   input_oat_location_arg += ImageHeader::GetOatLocationFromImageLocation(image_location);
    244 
    245   std::string output_oat_filename_arg("--output-oat-file=");
    246   output_oat_filename_arg += ImageHeader::GetOatLocationFromImageLocation(dest_filename);
    247 
    248   std::string instruction_set_arg("--instruction-set=");
    249   instruction_set_arg += GetInstructionSetString(isa);
    250 
    251   std::string base_offset_arg("--base-offset-delta=");
    252   StringAppendF(&base_offset_arg, "%d", ChooseRelocationOffsetDelta(ART_BASE_ADDRESS_MIN_DELTA,
    253                                                                     ART_BASE_ADDRESS_MAX_DELTA));
    254 
    255   std::vector<std::string> argv;
    256   argv.push_back(patchoat);
    257 
    258   argv.push_back(input_image_location_arg);
    259   argv.push_back(output_image_filename_arg);
    260 
    261   argv.push_back(input_oat_location_arg);
    262   argv.push_back(output_oat_filename_arg);
    263 
    264   argv.push_back(instruction_set_arg);
    265   argv.push_back(base_offset_arg);
    266 
    267   std::string command_line(Join(argv, ' '));
    268   LOG(INFO) << "RelocateImage: " << command_line;
    269   return Exec(argv, error_msg);
    270 }
    271 
    272 static ImageHeader* ReadSpecificImageHeader(const char* filename, std::string* error_msg) {
    273   std::unique_ptr<ImageHeader> hdr(new ImageHeader);
    274   if (!ReadSpecificImageHeader(filename, hdr.get())) {
    275     *error_msg = StringPrintf("Unable to read image header for %s", filename);
    276     return nullptr;
    277   }
    278   return hdr.release();
    279 }
    280 
    281 ImageHeader* ImageSpace::ReadImageHeaderOrDie(const char* image_location,
    282                                               const InstructionSet image_isa) {
    283   std::string error_msg;
    284   ImageHeader* image_header = ReadImageHeader(image_location, image_isa, &error_msg);
    285   if (image_header == nullptr) {
    286     LOG(FATAL) << error_msg;
    287   }
    288   return image_header;
    289 }
    290 
    291 ImageHeader* ImageSpace::ReadImageHeader(const char* image_location,
    292                                          const InstructionSet image_isa,
    293                                          std::string* error_msg) {
    294   std::string system_filename;
    295   bool has_system = false;
    296   std::string cache_filename;
    297   bool has_cache = false;
    298   bool dalvik_cache_exists = false;
    299   bool is_global_cache = false;
    300   if (FindImageFilename(image_location, image_isa, &system_filename, &has_system,
    301                         &cache_filename, &dalvik_cache_exists, &has_cache, &is_global_cache)) {
    302     if (Runtime::Current()->ShouldRelocate()) {
    303       if (has_system && has_cache) {
    304         std::unique_ptr<ImageHeader> sys_hdr(new ImageHeader);
    305         std::unique_ptr<ImageHeader> cache_hdr(new ImageHeader);
    306         if (!ReadSpecificImageHeader(system_filename.c_str(), sys_hdr.get())) {
    307           *error_msg = StringPrintf("Unable to read image header for %s at %s",
    308                                     image_location, system_filename.c_str());
    309           return nullptr;
    310         }
    311         if (!ReadSpecificImageHeader(cache_filename.c_str(), cache_hdr.get())) {
    312           *error_msg = StringPrintf("Unable to read image header for %s at %s",
    313                                     image_location, cache_filename.c_str());
    314           return nullptr;
    315         }
    316         if (sys_hdr->GetOatChecksum() != cache_hdr->GetOatChecksum()) {
    317           *error_msg = StringPrintf("Unable to find a relocated version of image file %s",
    318                                     image_location);
    319           return nullptr;
    320         }
    321         return cache_hdr.release();
    322       } else if (!has_cache) {
    323         *error_msg = StringPrintf("Unable to find a relocated version of image file %s",
    324                                   image_location);
    325         return nullptr;
    326       } else if (!has_system && has_cache) {
    327         // This can probably just use the cache one.
    328         return ReadSpecificImageHeader(cache_filename.c_str(), error_msg);
    329       }
    330     } else {
    331       // We don't want to relocate, Just pick the appropriate one if we have it and return.
    332       if (has_system && has_cache) {
    333         // We want the cache if the checksum matches, otherwise the system.
    334         std::unique_ptr<ImageHeader> system(ReadSpecificImageHeader(system_filename.c_str(),
    335                                                                     error_msg));
    336         std::unique_ptr<ImageHeader> cache(ReadSpecificImageHeader(cache_filename.c_str(),
    337                                                                    error_msg));
    338         if (system.get() == nullptr ||
    339             (cache.get() != nullptr && cache->GetOatChecksum() == system->GetOatChecksum())) {
    340           return cache.release();
    341         } else {
    342           return system.release();
    343         }
    344       } else if (has_system) {
    345         return ReadSpecificImageHeader(system_filename.c_str(), error_msg);
    346       } else if (has_cache) {
    347         return ReadSpecificImageHeader(cache_filename.c_str(), error_msg);
    348       }
    349     }
    350   }
    351 
    352   *error_msg = StringPrintf("Unable to find image file for %s", image_location);
    353   return nullptr;
    354 }
    355 
    356 static bool ChecksumsMatch(const char* image_a, const char* image_b) {
    357   ImageHeader hdr_a;
    358   ImageHeader hdr_b;
    359   return ReadSpecificImageHeader(image_a, &hdr_a) && ReadSpecificImageHeader(image_b, &hdr_b)
    360       && hdr_a.GetOatChecksum() == hdr_b.GetOatChecksum();
    361 }
    362 
    363 static bool ImageCreationAllowed(bool is_global_cache, std::string* error_msg) {
    364   // Anyone can write into a "local" cache.
    365   if (!is_global_cache) {
    366     return true;
    367   }
    368 
    369   // Only the zygote is allowed to create the global boot image.
    370   if (Runtime::Current()->IsZygote()) {
    371     return true;
    372   }
    373 
    374   *error_msg = "Only the zygote can create the global boot image.";
    375   return false;
    376 }
    377 
    378 ImageSpace* ImageSpace::Create(const char* image_location,
    379                                const InstructionSet image_isa,
    380                                std::string* error_msg) {
    381   std::string system_filename;
    382   bool has_system = false;
    383   std::string cache_filename;
    384   bool has_cache = false;
    385   bool dalvik_cache_exists = false;
    386   bool is_global_cache = true;
    387   const bool found_image = FindImageFilename(image_location, image_isa, &system_filename,
    388                                              &has_system, &cache_filename, &dalvik_cache_exists,
    389                                              &has_cache, &is_global_cache);
    390 
    391   ImageSpace* space;
    392   bool relocate = Runtime::Current()->ShouldRelocate();
    393   bool can_compile = Runtime::Current()->IsImageDex2OatEnabled();
    394   if (found_image) {
    395     const std::string* image_filename;
    396     bool is_system = false;
    397     bool relocated_version_used = false;
    398     if (relocate) {
    399       if (!dalvik_cache_exists) {
    400         *error_msg = StringPrintf("Requiring relocation for image '%s' at '%s' but we do not have "
    401                                   "any dalvik_cache to find/place it in.",
    402                                   image_location, system_filename.c_str());
    403         return nullptr;
    404       }
    405       if (has_system) {
    406         if (has_cache && ChecksumsMatch(system_filename.c_str(), cache_filename.c_str())) {
    407           // We already have a relocated version
    408           image_filename = &cache_filename;
    409           relocated_version_used = true;
    410         } else {
    411           // We cannot have a relocated version, Relocate the system one and use it.
    412 
    413           std::string reason;
    414           bool success;
    415 
    416           // Check whether we are allowed to relocate.
    417           if (!can_compile) {
    418             reason = "Image dex2oat disabled by -Xnoimage-dex2oat.";
    419             success = false;
    420           } else if (!ImageCreationAllowed(is_global_cache, &reason)) {
    421             // Whether we can write to the cache.
    422             success = false;
    423           } else {
    424             // Try to relocate.
    425             success = RelocateImage(image_location, cache_filename.c_str(), image_isa, &reason);
    426           }
    427 
    428           if (success) {
    429             relocated_version_used = true;
    430             image_filename = &cache_filename;
    431           } else {
    432             *error_msg = StringPrintf("Unable to relocate image '%s' from '%s' to '%s': %s",
    433                                       image_location, system_filename.c_str(),
    434                                       cache_filename.c_str(), reason.c_str());
    435             // We failed to create files, remove any possibly garbage output.
    436             // Since ImageCreationAllowed was true above, we are the zygote
    437             // and therefore the only process expected to generate these for
    438             // the device.
    439             PruneDexCache(image_isa);
    440             return nullptr;
    441           }
    442         }
    443       } else {
    444         CHECK(has_cache);
    445         // We can just use cache's since it should be fine. This might or might not be relocated.
    446         image_filename = &cache_filename;
    447       }
    448     } else {
    449       if (has_system && has_cache) {
    450         // Check they have the same cksum. If they do use the cache. Otherwise system.
    451         if (ChecksumsMatch(system_filename.c_str(), cache_filename.c_str())) {
    452           image_filename = &cache_filename;
    453           relocated_version_used = true;
    454         } else {
    455           image_filename = &system_filename;
    456           is_system = true;
    457         }
    458       } else if (has_system) {
    459         image_filename = &system_filename;
    460         is_system = true;
    461       } else {
    462         CHECK(has_cache);
    463         image_filename = &cache_filename;
    464       }
    465     }
    466     {
    467       // Note that we must not use the file descriptor associated with
    468       // ScopedFlock::GetFile to Init the image file. We want the file
    469       // descriptor (and the associated exclusive lock) to be released when
    470       // we leave Create.
    471       ScopedFlock image_lock;
    472       image_lock.Init(image_filename->c_str(), error_msg);
    473       VLOG(startup) << "Using image file " << image_filename->c_str() << " for image location "
    474                     << image_location;
    475       // If we are in /system we can assume the image is good. We can also
    476       // assume this if we are using a relocated image (i.e. image checksum
    477       // matches) since this is only different by the offset. We need this to
    478       // make sure that host tests continue to work.
    479       space = ImageSpace::Init(image_filename->c_str(), image_location,
    480                                !(is_system || relocated_version_used), error_msg);
    481     }
    482     if (space != nullptr) {
    483       return space;
    484     }
    485 
    486     if (relocated_version_used) {
    487       // Something is wrong with the relocated copy (even though checksums match). Cleanup.
    488       // This can happen if the .oat is corrupt, since the above only checks the .art checksums.
    489       // TODO: Check the oat file validity earlier.
    490       *error_msg = StringPrintf("Attempted to use relocated version of %s at %s generated from %s "
    491                                 "but image failed to load: %s",
    492                                 image_location, cache_filename.c_str(), system_filename.c_str(),
    493                                 error_msg->c_str());
    494       PruneDexCache(image_isa);
    495       return nullptr;
    496     } else if (is_system) {
    497       // If the /system file exists, it should be up-to-date, don't try to generate it.
    498       *error_msg = StringPrintf("Failed to load /system image '%s': %s",
    499                                 image_filename->c_str(), error_msg->c_str());
    500       return nullptr;
    501     } else {
    502       // Otherwise, log a warning and fall through to GenerateImage.
    503       LOG(WARNING) << *error_msg;
    504     }
    505   }
    506 
    507   if (!can_compile) {
    508     *error_msg = "Not attempting to compile image because -Xnoimage-dex2oat";
    509     return nullptr;
    510   } else if (!dalvik_cache_exists) {
    511     *error_msg = StringPrintf("No place to put generated image.");
    512     return nullptr;
    513   } else if (!ImageCreationAllowed(is_global_cache, error_msg)) {
    514     return nullptr;
    515   } else if (!GenerateImage(cache_filename, image_isa, error_msg)) {
    516     *error_msg = StringPrintf("Failed to generate image '%s': %s",
    517                               cache_filename.c_str(), error_msg->c_str());
    518     // We failed to create files, remove any possibly garbage output.
    519     // Since ImageCreationAllowed was true above, we are the zygote
    520     // and therefore the only process expected to generate these for
    521     // the device.
    522     PruneDexCache(image_isa);
    523     return nullptr;
    524   } else {
    525     // Note that we must not use the file descriptor associated with
    526     // ScopedFlock::GetFile to Init the image file. We want the file
    527     // descriptor (and the associated exclusive lock) to be released when
    528     // we leave Create.
    529     ScopedFlock image_lock;
    530     image_lock.Init(cache_filename.c_str(), error_msg);
    531     space = ImageSpace::Init(cache_filename.c_str(), image_location, true, error_msg);
    532     if (space == nullptr) {
    533       *error_msg = StringPrintf("Failed to load generated image '%s': %s",
    534                                 cache_filename.c_str(), error_msg->c_str());
    535     }
    536     return space;
    537   }
    538 }
    539 
    540 void ImageSpace::VerifyImageAllocations() {
    541   byte* current = Begin() + RoundUp(sizeof(ImageHeader), kObjectAlignment);
    542   while (current < End()) {
    543     DCHECK_ALIGNED(current, kObjectAlignment);
    544     mirror::Object* obj = reinterpret_cast<mirror::Object*>(current);
    545     CHECK(live_bitmap_->Test(obj));
    546     CHECK(obj->GetClass() != nullptr) << "Image object at address " << obj << " has null class";
    547     if (kUseBakerOrBrooksReadBarrier) {
    548       obj->AssertReadBarrierPointer();
    549     }
    550     current += RoundUp(obj->SizeOf(), kObjectAlignment);
    551   }
    552 }
    553 
    554 ImageSpace* ImageSpace::Init(const char* image_filename, const char* image_location,
    555                              bool validate_oat_file, std::string* error_msg) {
    556   CHECK(image_filename != nullptr);
    557   CHECK(image_location != nullptr);
    558 
    559   uint64_t start_time = 0;
    560   if (VLOG_IS_ON(heap) || VLOG_IS_ON(startup)) {
    561     start_time = NanoTime();
    562     LOG(INFO) << "ImageSpace::Init entering image_filename=" << image_filename;
    563   }
    564 
    565   std::unique_ptr<File> file(OS::OpenFileForReading(image_filename));
    566   if (file.get() == NULL) {
    567     *error_msg = StringPrintf("Failed to open '%s'", image_filename);
    568     return nullptr;
    569   }
    570   ImageHeader image_header;
    571   bool success = file->ReadFully(&image_header, sizeof(image_header));
    572   if (!success || !image_header.IsValid()) {
    573     *error_msg = StringPrintf("Invalid image header in '%s'", image_filename);
    574     return nullptr;
    575   }
    576 
    577   // Note: The image header is part of the image due to mmap page alignment required of offset.
    578   std::unique_ptr<MemMap> map(MemMap::MapFileAtAddress(image_header.GetImageBegin(),
    579                                                  image_header.GetImageSize(),
    580                                                  PROT_READ | PROT_WRITE,
    581                                                  MAP_PRIVATE,
    582                                                  file->Fd(),
    583                                                  0,
    584                                                  false,
    585                                                  image_filename,
    586                                                  error_msg));
    587   if (map.get() == NULL) {
    588     DCHECK(!error_msg->empty());
    589     return nullptr;
    590   }
    591   CHECK_EQ(image_header.GetImageBegin(), map->Begin());
    592   DCHECK_EQ(0, memcmp(&image_header, map->Begin(), sizeof(ImageHeader)));
    593 
    594   std::unique_ptr<MemMap> image_map(
    595       MemMap::MapFileAtAddress(nullptr, image_header.GetImageBitmapSize(),
    596                                PROT_READ, MAP_PRIVATE,
    597                                file->Fd(), image_header.GetBitmapOffset(),
    598                                false,
    599                                image_filename,
    600                                error_msg));
    601   if (image_map.get() == nullptr) {
    602     *error_msg = StringPrintf("Failed to map image bitmap: %s", error_msg->c_str());
    603     return nullptr;
    604   }
    605   uint32_t bitmap_index = bitmap_index_.FetchAndAddSequentiallyConsistent(1);
    606   std::string bitmap_name(StringPrintf("imagespace %s live-bitmap %u", image_filename,
    607                                        bitmap_index));
    608   std::unique_ptr<accounting::ContinuousSpaceBitmap> bitmap(
    609       accounting::ContinuousSpaceBitmap::CreateFromMemMap(bitmap_name, image_map.release(),
    610                                                           reinterpret_cast<byte*>(map->Begin()),
    611                                                           map->Size()));
    612   if (bitmap.get() == nullptr) {
    613     *error_msg = StringPrintf("Could not create bitmap '%s'", bitmap_name.c_str());
    614     return nullptr;
    615   }
    616 
    617   std::unique_ptr<ImageSpace> space(new ImageSpace(image_filename, image_location,
    618                                              map.release(), bitmap.release()));
    619 
    620   // VerifyImageAllocations() will be called later in Runtime::Init()
    621   // as some class roots like ArtMethod::java_lang_reflect_ArtMethod_
    622   // and ArtField::java_lang_reflect_ArtField_, which are used from
    623   // Object::SizeOf() which VerifyImageAllocations() calls, are not
    624   // set yet at this point.
    625 
    626   space->oat_file_.reset(space->OpenOatFile(image_filename, error_msg));
    627   if (space->oat_file_.get() == nullptr) {
    628     DCHECK(!error_msg->empty());
    629     return nullptr;
    630   }
    631 
    632   if (validate_oat_file && !space->ValidateOatFile(error_msg)) {
    633     DCHECK(!error_msg->empty());
    634     return nullptr;
    635   }
    636 
    637   Runtime* runtime = Runtime::Current();
    638   runtime->SetInstructionSet(space->oat_file_->GetOatHeader().GetInstructionSet());
    639 
    640   mirror::Object* resolution_method = image_header.GetImageRoot(ImageHeader::kResolutionMethod);
    641   runtime->SetResolutionMethod(down_cast<mirror::ArtMethod*>(resolution_method));
    642   mirror::Object* imt_conflict_method = image_header.GetImageRoot(ImageHeader::kImtConflictMethod);
    643   runtime->SetImtConflictMethod(down_cast<mirror::ArtMethod*>(imt_conflict_method));
    644   mirror::Object* default_imt = image_header.GetImageRoot(ImageHeader::kDefaultImt);
    645   runtime->SetDefaultImt(down_cast<mirror::ObjectArray<mirror::ArtMethod>*>(default_imt));
    646 
    647   mirror::Object* callee_save_method = image_header.GetImageRoot(ImageHeader::kCalleeSaveMethod);
    648   runtime->SetCalleeSaveMethod(down_cast<mirror::ArtMethod*>(callee_save_method),
    649                                Runtime::kSaveAll);
    650   callee_save_method = image_header.GetImageRoot(ImageHeader::kRefsOnlySaveMethod);
    651   runtime->SetCalleeSaveMethod(down_cast<mirror::ArtMethod*>(callee_save_method),
    652                                Runtime::kRefsOnly);
    653   callee_save_method = image_header.GetImageRoot(ImageHeader::kRefsAndArgsSaveMethod);
    654   runtime->SetCalleeSaveMethod(down_cast<mirror::ArtMethod*>(callee_save_method),
    655                                Runtime::kRefsAndArgs);
    656 
    657   if (VLOG_IS_ON(heap) || VLOG_IS_ON(startup)) {
    658     LOG(INFO) << "ImageSpace::Init exiting (" << PrettyDuration(NanoTime() - start_time)
    659              << ") " << *space.get();
    660   }
    661   return space.release();
    662 }
    663 
    664 OatFile* ImageSpace::OpenOatFile(const char* image_path, std::string* error_msg) const {
    665   const ImageHeader& image_header = GetImageHeader();
    666   std::string oat_filename = ImageHeader::GetOatLocationFromImageLocation(image_path);
    667 
    668   OatFile* oat_file = OatFile::Open(oat_filename, oat_filename, image_header.GetOatDataBegin(),
    669                                     !Runtime::Current()->IsCompiler(), error_msg);
    670   if (oat_file == NULL) {
    671     *error_msg = StringPrintf("Failed to open oat file '%s' referenced from image %s: %s",
    672                               oat_filename.c_str(), GetName(), error_msg->c_str());
    673     return nullptr;
    674   }
    675   uint32_t oat_checksum = oat_file->GetOatHeader().GetChecksum();
    676   uint32_t image_oat_checksum = image_header.GetOatChecksum();
    677   if (oat_checksum != image_oat_checksum) {
    678     *error_msg = StringPrintf("Failed to match oat file checksum 0x%x to expected oat checksum 0x%x"
    679                               " in image %s", oat_checksum, image_oat_checksum, GetName());
    680     return nullptr;
    681   }
    682   int32_t image_patch_delta = image_header.GetPatchDelta();
    683   int32_t oat_patch_delta = oat_file->GetOatHeader().GetImagePatchDelta();
    684   if (oat_patch_delta != image_patch_delta) {
    685     // We should have already relocated by this point. Bail out.
    686     *error_msg = StringPrintf("Failed to match oat file patch delta %d to expected patch delta %d "
    687                               "in image %s", oat_patch_delta, image_patch_delta, GetName());
    688     return nullptr;
    689   }
    690 
    691   return oat_file;
    692 }
    693 
    694 bool ImageSpace::ValidateOatFile(std::string* error_msg) const {
    695   CHECK(oat_file_.get() != NULL);
    696   for (const OatFile::OatDexFile* oat_dex_file : oat_file_->GetOatDexFiles()) {
    697     const std::string& dex_file_location = oat_dex_file->GetDexFileLocation();
    698     uint32_t dex_file_location_checksum;
    699     if (!DexFile::GetChecksum(dex_file_location.c_str(), &dex_file_location_checksum, error_msg)) {
    700       *error_msg = StringPrintf("Failed to get checksum of dex file '%s' referenced by image %s: "
    701                                 "%s", dex_file_location.c_str(), GetName(), error_msg->c_str());
    702       return false;
    703     }
    704     if (dex_file_location_checksum != oat_dex_file->GetDexFileLocationChecksum()) {
    705       *error_msg = StringPrintf("ValidateOatFile found checksum mismatch between oat file '%s' and "
    706                                 "dex file '%s' (0x%x != 0x%x)",
    707                                 oat_file_->GetLocation().c_str(), dex_file_location.c_str(),
    708                                 oat_dex_file->GetDexFileLocationChecksum(),
    709                                 dex_file_location_checksum);
    710       return false;
    711     }
    712   }
    713   return true;
    714 }
    715 
    716 const OatFile* ImageSpace::GetOatFile() const {
    717   return oat_file_.get();
    718 }
    719 
    720 OatFile* ImageSpace::ReleaseOatFile() {
    721   CHECK(oat_file_.get() != NULL);
    722   return oat_file_.release();
    723 }
    724 
    725 void ImageSpace::Dump(std::ostream& os) const {
    726   os << GetType()
    727       << " begin=" << reinterpret_cast<void*>(Begin())
    728       << ",end=" << reinterpret_cast<void*>(End())
    729       << ",size=" << PrettySize(Size())
    730       << ",name=\"" << GetName() << "\"]";
    731 }
    732 
    733 }  // namespace space
    734 }  // namespace gc
    735 }  // namespace art
    736