image_space.h revision 2974bc3d8a5d161d449dd66826d668d87bdc3cbe 
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 "gc/accounting/space_bitmap.h"
21#include "runtime.h"
22#include "space.h"
23
24namespace art {
25
26class OatFile;
27
28namespace gc {
29namespace space {
30
31// An image space is a space backed with a memory mapped image.
32class ImageSpace : public MemMapSpace {
33 public:
34  SpaceType GetType() const {
35    return kSpaceTypeImageSpace;
36  }
37
38  // Create a Space from an image file for a specified instruction
39  // set. Cannot be used for future allocation or collected.
40  //
41  // Create also opens the OatFile associated with the image file so
42  // that it be contiguously allocated with the image before the
43  // creation of the alloc space. The ReleaseOatFile will later be
44  // used to transfer ownership of the OatFile to the ClassLinker when
45  // it is initialized.
46  static ImageSpace* Create(const char* image, const InstructionSet image_isa)
47      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
48
49  // Releases the OatFile from the ImageSpace so it can be transfer to
50  // the caller, presumably the ClassLinker.
51  OatFile* ReleaseOatFile()
52      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
53
54  void VerifyImageAllocations()
55      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
56
57  const ImageHeader& GetImageHeader() const {
58    return *reinterpret_cast<ImageHeader*>(Begin());
59  }
60
61  const std::string GetImageFilename() const {
62    return GetName();
63  }
64
65  accounting::ContinuousSpaceBitmap* GetLiveBitmap() const OVERRIDE {
66    return live_bitmap_.get();
67  }
68
69  accounting::ContinuousSpaceBitmap* GetMarkBitmap() const OVERRIDE {
70    // ImageSpaces have the same bitmap for both live and marked. This helps reduce the number of
71    // special cases to test against.
72    return live_bitmap_.get();
73  }
74
75  void Dump(std::ostream& os) const;
76
77  // Sweeping image spaces is a NOP.
78  void Sweep(bool /* swap_bitmaps */, size_t* /* freed_objects */, size_t* /* freed_bytes */) {
79  }
80
81  bool CanMoveObjects() const OVERRIDE {
82    return false;
83  }
84
85 private:
86  // Tries to initialize an ImageSpace from the given image path,
87  // returning NULL on error.
88  //
89  // If validate_oat_file is false (for /system), do not verify that
90  // image's OatFile is up-to-date relative to its DexFile
91  // inputs. Otherwise (for /data), validate the inputs and generate
92  // the OatFile in /data/dalvik-cache if necessary.
93  static ImageSpace* Init(const char* image, bool validate_oat_file, std::string* error_msg)
94      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
95
96  OatFile* OpenOatFile(const char* image, std::string* error_msg) const
97      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
98
99  bool ValidateOatFile(std::string* error_msg) const
100      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
101
102  friend class Space;
103
104  static Atomic<uint32_t> bitmap_index_;
105
106  UniquePtr<accounting::ContinuousSpaceBitmap> live_bitmap_;
107
108  ImageSpace(const std::string& name, MemMap* mem_map,
109             accounting::ContinuousSpaceBitmap* live_bitmap);
110
111  // The OatFile associated with the image during early startup to
112  // reserve space contiguous to the image. It is later released to
113  // the ClassLinker during it's initialization.
114  UniquePtr<OatFile> oat_file_;
115
116  DISALLOW_COPY_AND_ASSIGN(ImageSpace);
117};
118
119}  // namespace space
120}  // namespace gc
121}  // namespace art
122
123#endif  // ART_RUNTIME_GC_SPACE_IMAGE_SPACE_H_
124