1 /* 2 * Copyright (C) 2014 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_PATCHOAT_PATCHOAT_H_ 18 #define ART_PATCHOAT_PATCHOAT_H_ 19 20 #include "arch/instruction_set.h" 21 #include "base/macros.h" 22 #include "base/mutex.h" 23 #include "elf_file.h" 24 #include "elf_utils.h" 25 #include "gc/accounting/space_bitmap.h" 26 #include "gc/space/image_space.h" 27 #include "gc/heap.h" 28 #include "os.h" 29 #include "runtime.h" 30 31 namespace art { 32 33 class ArtMethod; 34 class ImageHeader; 35 class OatHeader; 36 37 namespace mirror { 38 class Object; 39 class PointerArray; 40 class Reference; 41 class Class; 42 } // namespace mirror 43 44 class PatchOat { 45 public: 46 // Patch only the oat file 47 static bool Patch(File* oat_in, off_t delta, File* oat_out, TimingLogger* timings, 48 bool output_oat_opened_from_fd, // Was this using --oatput-oat-fd ? 49 bool new_oat_out); // Output oat was a new file created by us? 50 51 // Patch only the image (art file) 52 static bool Patch(const std::string& art_location, off_t delta, File* art_out, InstructionSet isa, 53 TimingLogger* timings); 54 55 // Patch both the image and the oat file 56 static bool Patch(const std::string& art_location, 57 off_t delta, 58 const std::string& output_directory, 59 InstructionSet isa, 60 TimingLogger* timings); 61 ~PatchOat()62 ~PatchOat() {} 63 PatchOat(PatchOat&&) = default; 64 65 private: 66 // Takes ownership only of the ElfFile. All other pointers are only borrowed. PatchOat(ElfFile * oat_file,off_t delta,TimingLogger * timings)67 PatchOat(ElfFile* oat_file, off_t delta, TimingLogger* timings) 68 : oat_file_(oat_file), image_(nullptr), bitmap_(nullptr), heap_(nullptr), delta_(delta), 69 isa_(kNone), space_map_(nullptr), timings_(timings) {} PatchOat(InstructionSet isa,MemMap * image,gc::accounting::ContinuousSpaceBitmap * bitmap,MemMap * heap,off_t delta,TimingLogger * timings)70 PatchOat(InstructionSet isa, MemMap* image, gc::accounting::ContinuousSpaceBitmap* bitmap, 71 MemMap* heap, off_t delta, TimingLogger* timings) 72 : image_(image), bitmap_(bitmap), heap_(heap), 73 delta_(delta), isa_(isa), space_map_(nullptr), timings_(timings) {} PatchOat(InstructionSet isa,ElfFile * oat_file,MemMap * image,gc::accounting::ContinuousSpaceBitmap * bitmap,MemMap * heap,off_t delta,std::map<gc::space::ImageSpace *,std::unique_ptr<MemMap>> * map,TimingLogger * timings)74 PatchOat(InstructionSet isa, ElfFile* oat_file, MemMap* image, 75 gc::accounting::ContinuousSpaceBitmap* bitmap, MemMap* heap, off_t delta, 76 std::map<gc::space::ImageSpace*, std::unique_ptr<MemMap>>* map, TimingLogger* timings) 77 : oat_file_(oat_file), image_(image), bitmap_(bitmap), heap_(heap), 78 delta_(delta), isa_(isa), space_map_(map), timings_(timings) {} 79 80 // Was the .art image at image_path made with --compile-pic ? 81 static bool IsImagePic(const ImageHeader& image_header, const std::string& image_path); 82 83 enum MaybePic { 84 NOT_PIC, // Code not pic. Patch as usual. 85 PIC, // Code was pic. Create symlink; skip OAT patching. 86 ERROR_OAT_FILE, // Failed to symlink oat file 87 ERROR_FIRST = ERROR_OAT_FILE, 88 }; 89 90 // Was the .oat image at oat_in made with --compile-pic ? 91 static MaybePic IsOatPic(const ElfFile* oat_in); 92 93 // Attempt to replace the file with a symlink 94 // Returns false if it fails 95 static bool ReplaceOatFileWithSymlink(const std::string& input_oat_filename, 96 const std::string& output_oat_filename, 97 bool output_oat_opened_from_fd, 98 bool new_oat_out); // Output oat was newly created? 99 BitmapCallback(mirror::Object * obj,void * arg)100 static void BitmapCallback(mirror::Object* obj, void* arg) 101 SHARED_REQUIRES(Locks::mutator_lock_) { 102 reinterpret_cast<PatchOat*>(arg)->VisitObject(obj); 103 } 104 105 void VisitObject(mirror::Object* obj) 106 SHARED_REQUIRES(Locks::mutator_lock_); 107 void FixupMethod(ArtMethod* object, ArtMethod* copy) 108 SHARED_REQUIRES(Locks::mutator_lock_); 109 110 // Patches oat in place, modifying the oat_file given to the constructor. 111 bool PatchElf(); 112 template <typename ElfFileImpl> 113 bool PatchElf(ElfFileImpl* oat_file); 114 template <typename ElfFileImpl> 115 bool PatchOatHeader(ElfFileImpl* oat_file); 116 117 bool PatchImage(bool primary_image) SHARED_REQUIRES(Locks::mutator_lock_); 118 void PatchArtFields(const ImageHeader* image_header) SHARED_REQUIRES(Locks::mutator_lock_); 119 void PatchArtMethods(const ImageHeader* image_header) SHARED_REQUIRES(Locks::mutator_lock_); 120 void PatchImtConflictTables(const ImageHeader* image_header) 121 SHARED_REQUIRES(Locks::mutator_lock_); 122 void PatchInternedStrings(const ImageHeader* image_header) 123 SHARED_REQUIRES(Locks::mutator_lock_); 124 void PatchClassTable(const ImageHeader* image_header) 125 SHARED_REQUIRES(Locks::mutator_lock_); 126 void PatchDexFileArrays(mirror::ObjectArray<mirror::Object>* img_roots) 127 SHARED_REQUIRES(Locks::mutator_lock_); 128 129 bool WriteElf(File* out); 130 bool WriteImage(File* out); 131 132 template <typename T> RelocatedCopyOf(T * obj)133 T* RelocatedCopyOf(T* obj) const { 134 if (obj == nullptr) { 135 return nullptr; 136 } 137 DCHECK_GT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->Begin())); 138 DCHECK_LT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->End())); 139 uintptr_t heap_off = 140 reinterpret_cast<uintptr_t>(obj) - reinterpret_cast<uintptr_t>(heap_->Begin()); 141 DCHECK_LT(heap_off, image_->Size()); 142 return reinterpret_cast<T*>(image_->Begin() + heap_off); 143 } 144 145 template <typename T> RelocatedCopyOfFollowImages(T * obj)146 T* RelocatedCopyOfFollowImages(T* obj) const { 147 if (obj == nullptr) { 148 return nullptr; 149 } 150 // Find ImageSpace this belongs to. 151 auto image_spaces = Runtime::Current()->GetHeap()->GetBootImageSpaces(); 152 for (gc::space::ImageSpace* image_space : image_spaces) { 153 if (image_space->Contains(obj)) { 154 uintptr_t heap_off = reinterpret_cast<uintptr_t>(obj) - 155 reinterpret_cast<uintptr_t>(image_space->GetMemMap()->Begin()); 156 return reinterpret_cast<T*>(space_map_->find(image_space)->second->Begin() + heap_off); 157 } 158 } 159 LOG(FATAL) << "Did not find object in boot image space " << obj; 160 UNREACHABLE(); 161 } 162 163 template <typename T> RelocatedAddressOfPointer(T * obj)164 T* RelocatedAddressOfPointer(T* obj) const { 165 if (obj == nullptr) { 166 return obj; 167 } 168 auto ret = reinterpret_cast<uintptr_t>(obj) + delta_; 169 // Trim off high bits in case negative relocation with 64 bit patchoat. 170 if (InstructionSetPointerSize(isa_) == sizeof(uint32_t)) { 171 ret = static_cast<uintptr_t>(static_cast<uint32_t>(ret)); 172 } 173 return reinterpret_cast<T*>(ret); 174 } 175 176 template <typename T> RelocatedAddressOfIntPointer(T obj)177 T RelocatedAddressOfIntPointer(T obj) const { 178 if (obj == 0) { 179 return obj; 180 } 181 T ret = obj + delta_; 182 // Trim off high bits in case negative relocation with 64 bit patchoat. 183 if (InstructionSetPointerSize(isa_) == 4) { 184 ret = static_cast<T>(static_cast<uint32_t>(ret)); 185 } 186 return ret; 187 } 188 189 // Walks through the old image and patches the mmap'd copy of it to the new offset. It does not 190 // change the heap. 191 class PatchVisitor { 192 public: PatchVisitor(PatchOat * patcher,mirror::Object * copy)193 PatchVisitor(PatchOat* patcher, mirror::Object* copy) : patcher_(patcher), copy_(copy) {} ~PatchVisitor()194 ~PatchVisitor() {} 195 void operator() (mirror::Object* obj, MemberOffset off, bool b) const 196 REQUIRES(Locks::mutator_lock_, Locks::heap_bitmap_lock_); 197 // For reference classes. 198 void operator() (mirror::Class* cls, mirror::Reference* ref) const 199 REQUIRES(Locks::mutator_lock_, Locks::heap_bitmap_lock_); 200 // TODO: Consider using these for updating native class roots? VisitRootIfNonNull(mirror::CompressedReference<mirror::Object> * root ATTRIBUTE_UNUSED)201 void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) 202 const {} VisitRoot(mirror::CompressedReference<mirror::Object> * root ATTRIBUTE_UNUSED)203 void VisitRoot(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) const {} 204 205 private: 206 PatchOat* const patcher_; 207 mirror::Object* const copy_; 208 }; 209 210 // The elf file we are patching. 211 std::unique_ptr<ElfFile> oat_file_; 212 // A mmap of the image we are patching. This is modified. 213 const MemMap* const image_; 214 // The bitmap over the image within the heap we are patching. This is not modified. 215 gc::accounting::ContinuousSpaceBitmap* const bitmap_; 216 // The heap we are patching. This is not modified. 217 const MemMap* const heap_; 218 // The amount we are changing the offset by. 219 const off_t delta_; 220 // Active instruction set, used to know the entrypoint size. 221 const InstructionSet isa_; 222 223 const std::map<gc::space::ImageSpace*, std::unique_ptr<MemMap>>* space_map_; 224 225 TimingLogger* timings_; 226 227 friend class FixupRootVisitor; 228 friend class RelocatedPointerVisitor; 229 friend class PatchOatArtFieldVisitor; 230 friend class PatchOatArtMethodVisitor; 231 DISALLOW_IMPLICIT_CONSTRUCTORS(PatchOat); 232 }; 233 234 } // namespace art 235 #endif // ART_PATCHOAT_PATCHOAT_H_ 236