image_space.h revision 31f441464c0c8f840aba37e236ad133f30308d70 
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 "space.h"
21
22namespace art {
23
24class OatFile;
25
26namespace gc {
27namespace space {
28
29// An image space is a space backed with a memory mapped image.
30class ImageSpace : public MemMapSpace {
31 public:
32  SpaceType GetType() const {
33    return kSpaceTypeImageSpace;
34  }
35
36  // Create a Space from an image file. Cannot be used for future
37  // allocation or collected.
38  //
39  // Create also opens the OatFile associated with the image file so
40  // that it be contiguously allocated with the image before the
41  // creation of the alloc space. The ReleaseOatFile will later be
42  // used to transfer ownership of the OatFile to the ClassLinker when
43  // it is initialized.
44  static ImageSpace* Create(const char* image) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
45
46  // Releases the OatFile from the ImageSpace so it can be transfer to
47  // the caller, presumably the ClassLinker.
48  OatFile* ReleaseOatFile()
49      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
50
51  void VerifyImageAllocations()
52      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
53
54  const ImageHeader& GetImageHeader() const {
55    return *reinterpret_cast<ImageHeader*>(Begin());
56  }
57
58  const std::string GetImageFilename() const {
59    return GetName();
60  }
61
62  accounting::SpaceBitmap* GetLiveBitmap() const {
63    return live_bitmap_.get();
64  }
65
66  accounting::SpaceBitmap* GetMarkBitmap() const {
67    // ImageSpaces have the same bitmap for both live and marked. This helps reduce the number of
68    // special cases to test against.
69    return live_bitmap_.get();
70  }
71
72  void Dump(std::ostream& os) const;
73
74  // Sweeping image spaces is a NOP.
75  void Sweep(bool /* swap_bitmaps */, size_t* /* freed_objects */, size_t* /* freed_bytes */) {
76  }
77
78  bool CanMoveObjects() const OVERRIDE {
79    return false;
80  }
81
82 private:
83  // Tries to initialize an ImageSpace from the given image path,
84  // returning NULL on error.
85  //
86  // If validate_oat_file is false (for /system), do not verify that
87  // image's OatFile is up-to-date relative to its DexFile
88  // inputs. Otherwise (for /data), validate the inputs and generate
89  // the OatFile in /data/dalvik-cache if necessary.
90  static ImageSpace* Init(const char* image, bool validate_oat_file, std::string* error_msg)
91      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
92
93  OatFile* OpenOatFile(const char* image, std::string* error_msg) const
94      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
95
96  bool ValidateOatFile(std::string* error_msg) const
97      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
98
99  friend class Space;
100
101  static Atomic<uint32_t> bitmap_index_;
102
103  UniquePtr<accounting::SpaceBitmap> live_bitmap_;
104
105  ImageSpace(const std::string& name, MemMap* mem_map, accounting::SpaceBitmap* live_bitmap);
106
107  // The OatFile associated with the image during early startup to
108  // reserve space contiguous to the image. It is later released to
109  // the ClassLinker during it's initialization.
110  UniquePtr<OatFile> oat_file_;
111
112  DISALLOW_COPY_AND_ASSIGN(ImageSpace);
113};
114
115}  // namespace space
116}  // namespace gc
117}  // namespace art
118
119#endif  // ART_RUNTIME_GC_SPACE_IMAGE_SPACE_H_
120