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 #ifndef ART_RUNTIME_GC_SPACE_IMAGE_SPACE_H_
18 #define ART_RUNTIME_GC_SPACE_IMAGE_SPACE_H_
19 
20 #include "arch/instruction_set.h"
21 #include "gc/accounting/space_bitmap.h"
22 #include "runtime.h"
23 #include "space.h"
24 
25 namespace art {
26 
27 class OatFile;
28 
29 namespace gc {
30 namespace space {
31 
32 // An image space is a space backed with a memory mapped image.
33 class ImageSpace : public MemMapSpace {
34  public:
GetType()35   SpaceType GetType() const {
36     return kSpaceTypeImageSpace;
37   }
38 
39   // Load boot image spaces from a primary image file for a specified instruction set.
40   //
41   // On successful return, the loaded spaces are added to boot_image_spaces (which must be
42   // empty on entry) and oat_file_end is updated with the (page-aligned) end of the last
43   // oat file.
44   static bool LoadBootImage(const std::string& image_file_name,
45                             const InstructionSet image_instruction_set,
46                             std::vector<space::ImageSpace*>* boot_image_spaces,
47                             uint8_t** oat_file_end)
48       REQUIRES_SHARED(Locks::mutator_lock_);
49 
50   // Try to open an existing app image space.
51   static std::unique_ptr<ImageSpace> CreateFromAppImage(const char* image,
52                                                         const OatFile* oat_file,
53                                                         std::string* error_msg)
54       REQUIRES_SHARED(Locks::mutator_lock_);
55 
56   // Reads the image header from the specified image location for the
57   // instruction set image_isa. Returns null on failure, with
58   // reason in error_msg.
59   static ImageHeader* ReadImageHeader(const char* image_location,
60                                       InstructionSet image_isa,
61                                       std::string* error_msg);
62 
63   // Give access to the OatFile.
64   const OatFile* GetOatFile() const;
65 
66   // Releases the OatFile from the ImageSpace so it can be transfer to
67   // the caller, presumably the OatFileManager.
68   std::unique_ptr<const OatFile> ReleaseOatFile();
69 
70   void VerifyImageAllocations()
71       REQUIRES_SHARED(Locks::mutator_lock_);
72 
GetImageHeader()73   const ImageHeader& GetImageHeader() const {
74     return *reinterpret_cast<ImageHeader*>(Begin());
75   }
76 
77   // Actual filename where image was loaded from.
78   // For example: /data/dalvik-cache/arm/system@framework@boot.art
GetImageFilename()79   const std::string GetImageFilename() const {
80     return GetName();
81   }
82 
83   // Symbolic location for image.
84   // For example: /system/framework/boot.art
GetImageLocation()85   const std::string GetImageLocation() const {
86     return image_location_;
87   }
88 
GetLiveBitmap()89   accounting::ContinuousSpaceBitmap* GetLiveBitmap() const OVERRIDE {
90     return live_bitmap_.get();
91   }
92 
GetMarkBitmap()93   accounting::ContinuousSpaceBitmap* GetMarkBitmap() const OVERRIDE {
94     // ImageSpaces have the same bitmap for both live and marked. This helps reduce the number of
95     // special cases to test against.
96     return live_bitmap_.get();
97   }
98 
99   void Dump(std::ostream& os) const;
100 
101   // Sweeping image spaces is a NOP.
Sweep(bool,size_t *,size_t *)102   void Sweep(bool /* swap_bitmaps */, size_t* /* freed_objects */, size_t* /* freed_bytes */) {
103   }
104 
CanMoveObjects()105   bool CanMoveObjects() const OVERRIDE {
106     return false;
107   }
108 
109   // Returns the filename of the image corresponding to
110   // requested image_location, or the filename where a new image
111   // should be written if one doesn't exist. Looks for a generated
112   // image in the specified location and then in the dalvik-cache.
113   //
114   // Returns true if an image was found, false otherwise.
115   static bool FindImageFilename(const char* image_location,
116                                 InstructionSet image_isa,
117                                 std::string* system_location,
118                                 bool* has_system,
119                                 std::string* data_location,
120                                 bool* dalvik_cache_exists,
121                                 bool* has_data,
122                                 bool *is_global_cache);
123 
124   // Use the input image filename to adapt the names in the given boot classpath to establish
125   // complete locations for secondary images.
126   static void ExtractMultiImageLocations(const std::string& input_image_file_name,
127                                         const std::string& boot_classpath,
128                                         std::vector<std::string>* image_filenames);
129 
130   static std::string GetMultiImageBootClassPath(const std::vector<const char*>& dex_locations,
131                                                 const std::vector<const char*>& oat_filenames,
132                                                 const std::vector<const char*>& image_filenames);
133 
134   // Returns true if the dex checksums in the given oat file match the
135   // checksums of the original dex files on disk. This is intended to be used
136   // to validate the boot image oat file, which may contain dex entries from
137   // multiple different (possibly multidex) dex files on disk. Prefer the
138   // OatFileAssistant for validating regular app oat files because the
139   // OatFileAssistant caches dex checksums that are reused to check both the
140   // oat and odex file.
141   //
142   // This function is exposed for testing purposes.
143   static bool ValidateOatFile(const OatFile& oat_file, std::string* error_msg);
144 
145   // Return the end of the image which includes non-heap objects such as ArtMethods and ArtFields.
GetImageEnd()146   uint8_t* GetImageEnd() const {
147     return Begin() + GetImageHeader().GetImageSize();
148   }
149 
150   // Return the start of the associated oat file.
GetOatFileBegin()151   uint8_t* GetOatFileBegin() const {
152     return GetImageHeader().GetOatFileBegin();
153   }
154 
155   // Return the end of the associated oat file.
GetOatFileEnd()156   uint8_t* GetOatFileEnd() const {
157     return GetImageHeader().GetOatFileEnd();
158   }
159 
160   void DumpSections(std::ostream& os) const;
161 
162   // De-initialize the image-space by undoing the effects in Init().
163   virtual ~ImageSpace();
164 
165  protected:
166   // Tries to initialize an ImageSpace from the given image path, returning null on error.
167   //
168   // If validate_oat_file is false (for /system), do not verify that image's OatFile is up-to-date
169   // relative to its DexFile inputs. Otherwise (for /data), validate the inputs and generate the
170   // OatFile in /data/dalvik-cache if necessary. If the oat_file is null, it uses the oat file from
171   // the image.
172   static std::unique_ptr<ImageSpace> Init(const char* image_filename,
173                                           const char* image_location,
174                                           bool validate_oat_file,
175                                           const OatFile* oat_file,
176                                           std::string* error_msg)
177       REQUIRES_SHARED(Locks::mutator_lock_);
178 
179   static Atomic<uint32_t> bitmap_index_;
180 
181   std::unique_ptr<accounting::ContinuousSpaceBitmap> live_bitmap_;
182 
183   ImageSpace(const std::string& name,
184              const char* image_location,
185              MemMap* mem_map,
186              accounting::ContinuousSpaceBitmap* live_bitmap,
187              uint8_t* end);
188 
189   // The OatFile associated with the image during early startup to
190   // reserve space contiguous to the image. It is later released to
191   // the ClassLinker during it's initialization.
192   std::unique_ptr<OatFile> oat_file_;
193 
194   // There are times when we need to find the boot image oat file. As
195   // we release ownership during startup, keep a non-owned reference.
196   const OatFile* oat_file_non_owned_;
197 
198   const std::string image_location_;
199 
200   friend class ImageSpaceLoader;
201   friend class Space;
202 
203  private:
204   // Create a boot image space from an image file for a specified instruction
205   // set. Cannot be used for future allocation or collected.
206   //
207   // Create also opens the OatFile associated with the image file so
208   // that it be contiguously allocated with the image before the
209   // creation of the alloc space. The ReleaseOatFile will later be
210   // used to transfer ownership of the OatFile to the ClassLinker when
211   // it is initialized.
212   static std::unique_ptr<ImageSpace> CreateBootImage(const char* image,
213                                      InstructionSet image_isa,
214                                      bool secondary_image,
215                                      std::string* error_msg)
216       REQUIRES_SHARED(Locks::mutator_lock_);
217 
218   DISALLOW_COPY_AND_ASSIGN(ImageSpace);
219 };
220 
221 }  // namespace space
222 }  // namespace gc
223 }  // namespace art
224 
225 #endif  // ART_RUNTIME_GC_SPACE_IMAGE_SPACE_H_
226