/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ART_RUNTIME_IMAGE_H_
#define ART_RUNTIME_IMAGE_H_
#include <string.h>
#include "base/enums.h"
#include "base/iteration_range.h"
#include "mirror/object.h"
#include "runtime_globals.h"
namespace art {
class ArtField;
class ArtMethod;
template <class MirrorType> class ObjPtr;
namespace linker {
class ImageWriter;
} // namespace linker
class ObjectVisitor {
public:
virtual ~ObjectVisitor() {}
virtual void Visit(mirror::Object* object) = 0;
};
class PACKED(4) ImageSection {
public:
ImageSection() : offset_(0), size_(0) { }
ImageSection(uint32_t offset, uint32_t size) : offset_(offset), size_(size) { }
ImageSection(const ImageSection& section) = default;
ImageSection& operator=(const ImageSection& section) = default;
uint32_t Offset() const {
return offset_;
}
uint32_t Size() const {
return size_;
}
uint32_t End() const {
return Offset() + Size();
}
bool Contains(uint64_t offset) const {
return offset - offset_ < size_;
}
private:
uint32_t offset_;
uint32_t size_;
};
// Header of image files written by ImageWriter, read and validated by Space.
// Packed to object alignment since the first object follows directly after the header.
static_assert(kObjectAlignment == 8, "Alignment check");
class PACKED(8) ImageHeader {
public:
enum StorageMode : uint32_t {
kStorageModeUncompressed,
kStorageModeLZ4,
kStorageModeLZ4HC,
kStorageModeCount, // Number of elements in enum.
};
static constexpr StorageMode kDefaultStorageMode = kStorageModeUncompressed;
// Solid block of the image. May be compressed or uncompressed.
class PACKED(4) Block final {
public:
Block(StorageMode storage_mode,
uint32_t data_offset,
uint32_t data_size,
uint32_t image_offset,
uint32_t image_size)
: storage_mode_(storage_mode),
data_offset_(data_offset),
data_size_(data_size),
image_offset_(image_offset),
image_size_(image_size) {}
bool Decompress(uint8_t* out_ptr, const uint8_t* in_ptr, std::string* error_msg) const;
StorageMode GetStorageMode() const {
return storage_mode_;
}
uint32_t GetDataSize() const {
return data_size_;
}
uint32_t GetImageSize() const {
return image_size_;
}
private:
// Storage method for the image, the image may be compressed.
StorageMode storage_mode_ = kDefaultStorageMode;
// Compressed offset and size.
uint32_t data_offset_ = 0u;
uint32_t data_size_ = 0u;
// Image offset and size (decompressed or mapped location).
uint32_t image_offset_ = 0u;
uint32_t image_size_ = 0u;
};
ImageHeader() {}
ImageHeader(uint32_t image_reservation_size,
uint32_t component_count,
uint32_t image_begin,
uint32_t image_size,
ImageSection* sections,
uint32_t image_roots,
uint32_t oat_checksum,
uint32_t oat_file_begin,
uint32_t oat_data_begin,
uint32_t oat_data_end,
uint32_t oat_file_end,
uint32_t boot_image_begin,
uint32_t boot_image_size,
uint32_t pointer_size);
bool IsValid() const;
const char* GetMagic() const;
uint32_t GetImageReservationSize() const {
return image_reservation_size_;
}
uint32_t GetComponentCount() const {
return component_count_;
}
uint8_t* GetImageBegin() const {
return reinterpret_cast<uint8_t*>(image_begin_);
}
size_t GetImageSize() const {
return image_size_;
}
uint32_t GetImageChecksum() const {
return image_checksum_;
}
void SetImageChecksum(uint32_t image_checksum) {
image_checksum_ = image_checksum;
}
uint32_t GetOatChecksum() const {
return oat_checksum_;
}
void SetOatChecksum(uint32_t oat_checksum) {
oat_checksum_ = oat_checksum;
}
// The location that the oat file was expected to be when the image was created. The actual
// oat file may be at a different location for application images.
uint8_t* GetOatFileBegin() const {
return reinterpret_cast<uint8_t*>(oat_file_begin_);
}
uint8_t* GetOatDataBegin() const {
return reinterpret_cast<uint8_t*>(oat_data_begin_);
}
uint8_t* GetOatDataEnd() const {
return reinterpret_cast<uint8_t*>(oat_data_end_);
}
uint8_t* GetOatFileEnd() const {
return reinterpret_cast<uint8_t*>(oat_file_end_);
}
PointerSize GetPointerSize() const;
uint32_t GetPointerSizeUnchecked() const {
return pointer_size_;
}
static std::string GetOatLocationFromImageLocation(const std::string& image) {
return GetLocationFromImageLocation(image, "oat");
}
static std::string GetVdexLocationFromImageLocation(const std::string& image) {
return GetLocationFromImageLocation(image, "vdex");
}
enum ImageMethod {
kResolutionMethod,
kImtConflictMethod,
kImtUnimplementedMethod,
kSaveAllCalleeSavesMethod,
kSaveRefsOnlyMethod,
kSaveRefsAndArgsMethod,
kSaveEverythingMethod,
kSaveEverythingMethodForClinit,
kSaveEverythingMethodForSuspendCheck,
kImageMethodsCount, // Number of elements in enum.
};
enum ImageRoot {
kDexCaches,
kClassRoots,
kOomeWhenThrowingException, // Pre-allocated OOME when throwing exception.
kOomeWhenThrowingOome, // Pre-allocated OOME when throwing OOME.
kOomeWhenHandlingStackOverflow, // Pre-allocated OOME when handling StackOverflowError.
kNoClassDefFoundError, // Pre-allocated NoClassDefFoundError.
kSpecialRoots, // Different for boot image and app image, see aliases below.
kImageRootsMax,
// Aliases.
kAppImageClassLoader = kSpecialRoots, // The class loader used to build the app image.
kBootImageLiveObjects = kSpecialRoots, // Array of boot image objects that must be kept live.
};
/*
* This describes the number and ordering of sections inside of Boot
* and App Images. It is very important that changes to this struct
* are reflected in the compiler and loader.
*
* See:
* - ImageWriter::ImageInfo::CreateImageSections()
* - ImageWriter::Write()
* - ImageWriter::AllocMemory()
*/
enum ImageSections {
kSectionObjects,
kSectionArtFields,
kSectionArtMethods,
kSectionRuntimeMethods,
kSectionImTables,
kSectionIMTConflictTables,
kSectionDexCacheArrays,
kSectionInternedStrings,
kSectionClassTable,
kSectionStringReferenceOffsets,
kSectionMetadata,
kSectionImageBitmap,
kSectionCount, // Number of elements in enum.
};
static size_t NumberOfImageRoots(bool app_image ATTRIBUTE_UNUSED) {
// At the moment, boot image and app image have the same number of roots,
// though the meaning of the kSpecialRoots is different.
return kImageRootsMax;
}
ArtMethod* GetImageMethod(ImageMethod index) const;
ImageSection& GetImageSection(ImageSections index) {
DCHECK_LT(static_cast<size_t>(index), kSectionCount);
return sections_[index];
}
const ImageSection& GetImageSection(ImageSections index) const {
DCHECK_LT(static_cast<size_t>(index), kSectionCount);
return sections_[index];
}
const ImageSection& GetObjectsSection() const {
return GetImageSection(kSectionObjects);
}
const ImageSection& GetFieldsSection() const {
return GetImageSection(ImageHeader::kSectionArtFields);
}
const ImageSection& GetMethodsSection() const {
return GetImageSection(kSectionArtMethods);
}
const ImageSection& GetRuntimeMethodsSection() const {
return GetImageSection(kSectionRuntimeMethods);
}
const ImageSection& GetImTablesSection() const {
return GetImageSection(kSectionImTables);
}
const ImageSection& GetIMTConflictTablesSection() const {
return GetImageSection(kSectionIMTConflictTables);
}
const ImageSection& GetDexCacheArraysSection() const {
return GetImageSection(kSectionDexCacheArrays);
}
const ImageSection& GetInternedStringsSection() const {
return GetImageSection(kSectionInternedStrings);
}
const ImageSection& GetClassTableSection() const {
return GetImageSection(kSectionClassTable);
}
const ImageSection& GetImageStringReferenceOffsetsSection() const {
return GetImageSection(kSectionStringReferenceOffsets);
}
const ImageSection& GetMetadataSection() const {
return GetImageSection(kSectionMetadata);
}
const ImageSection& GetImageBitmapSection() const {
return GetImageSection(kSectionImageBitmap);
}
template <ReadBarrierOption kReadBarrierOption = kWithReadBarrier>
ObjPtr<mirror::Object> GetImageRoot(ImageRoot image_root) const
REQUIRES_SHARED(Locks::mutator_lock_);
template <ReadBarrierOption kReadBarrierOption = kWithReadBarrier>
ObjPtr<mirror::ObjectArray<mirror::Object>> GetImageRoots() const
REQUIRES_SHARED(Locks::mutator_lock_);
void RelocateImage(int64_t delta);
void RelocateImageMethods(int64_t delta);
void RelocateImageObjects(int64_t delta);
uint32_t GetBootImageBegin() const {
return boot_image_begin_;
}
uint32_t GetBootImageSize() const {
return boot_image_size_;
}
uint64_t GetDataSize() const {
return data_size_;
}
bool IsAppImage() const {
// App images currently require a boot image, if the size is non zero then it is an app image
// header.
return boot_image_size_ != 0u;
}
// Visit mirror::Objects in the section starting at base.
// TODO: Delete base parameter if it is always equal to GetImageBegin.
void VisitObjects(ObjectVisitor* visitor,
uint8_t* base,
PointerSize pointer_size) const
REQUIRES_SHARED(Locks::mutator_lock_);
// Visit ArtMethods in the section starting at base. Includes runtime methods.
// TODO: Delete base parameter if it is always equal to GetImageBegin.
// NO_THREAD_SAFETY_ANALYSIS for template visitor pattern.
template <typename Visitor>
void VisitPackedArtMethods(const Visitor& visitor,
uint8_t* base,
PointerSize pointer_size) const NO_THREAD_SAFETY_ANALYSIS;
// Visit ArtMethods in the section starting at base.
// TODO: Delete base parameter if it is always equal to GetImageBegin.
// NO_THREAD_SAFETY_ANALYSIS for template visitor pattern.
template <typename Visitor>
void VisitPackedArtFields(const Visitor& visitor, uint8_t* base) const NO_THREAD_SAFETY_ANALYSIS;
template <typename Visitor>
void VisitPackedImTables(const Visitor& visitor,
uint8_t* base,
PointerSize pointer_size) const;
template <typename Visitor>
void VisitPackedImtConflictTables(const Visitor& visitor,
uint8_t* base,
PointerSize pointer_size) const;
IterationRange<const Block*> GetBlocks() const {
return GetBlocks(GetImageBegin());
}
IterationRange<const Block*> GetBlocks(const uint8_t* image_begin) const {
const Block* begin = reinterpret_cast<const Block*>(image_begin + blocks_offset_);
return {begin, begin + blocks_count_};
}
// Return true if the image has any compressed blocks.
bool HasCompressedBlock() const {
return blocks_count_ != 0u;
}
uint32_t GetBlockCount() const {
return blocks_count_;
}
private:
static const uint8_t kImageMagic[4];
static const uint8_t kImageVersion[4];
static std::string GetLocationFromImageLocation(const std::string& image,
const std::string& extension) {
std::string filename = image;
if (filename.length() <= 3) {
filename += "." + extension;
} else {
filename.replace(filename.length() - 3, 3, extension);
}
return filename;
}
uint8_t magic_[4];
uint8_t version_[4];
// The total memory reservation size for the image.
// For boot image or boot image extension, the primary image includes the reservation
// for all image files and oat files, secondary images have the reservation set to 0.
// App images have reservation equal to `image_size_` rounded up to page size because
// their oat files are mmapped independently.
uint32_t image_reservation_size_ = 0u;
// The number of components.
// For boot image or boot image extension, the primary image stores the total number
// of images, secondary images have this set to 0.
// App images have 1 component.
uint32_t component_count_ = 0u;
// Required base address for mapping the image.
uint32_t image_begin_ = 0u;
// Image size, not page aligned.
uint32_t image_size_ = 0u;
// Image file checksum (calculated with the checksum field set to 0).
uint32_t image_checksum_ = 0u;
// Checksum of the oat file we link to for load time sanity check.
uint32_t oat_checksum_ = 0u;
// Start address for oat file. Will be before oat_data_begin_ for .so files.
uint32_t oat_file_begin_ = 0u;
// Required oat address expected by image Method::GetCode() pointers.
uint32_t oat_data_begin_ = 0u;
// End of oat data address range for this image file.
uint32_t oat_data_end_ = 0u;
// End of oat file address range. will be after oat_data_end_ for
// .so files. Used for positioning a following alloc spaces.
uint32_t oat_file_end_ = 0u;
// Boot image begin and end (app image headers only).
uint32_t boot_image_begin_ = 0u;
uint32_t boot_image_size_ = 0u; // Includes heap (*.art) and code (.oat).
// Absolute address of an Object[] of objects needed to reinitialize from an image.
uint32_t image_roots_ = 0u;
// Pointer size, this affects the size of the ArtMethods.
uint32_t pointer_size_ = 0u;
// Image section sizes/offsets correspond to the uncompressed form.
ImageSection sections_[kSectionCount];
// Image methods, may be inside of the boot image for app images.
uint64_t image_methods_[kImageMethodsCount];
// Data size for the image data excluding the bitmap and the header. For compressed images, this
// is the compressed size in the file.
uint32_t data_size_ = 0u;
// Image blocks, only used for compressed images.
uint32_t blocks_offset_ = 0u;
uint32_t blocks_count_ = 0u;
friend class linker::ImageWriter;
};
/*
* This type holds the information necessary to fix up AppImage string
* references.
*
* The first element of the pair is an offset into the image space. If the
* offset is tagged (testable using HasDexCacheNativeRefTag) it indicates the location
* of a DexCache object that has one or more native references to managed
* strings that need to be fixed up. In this case the second element has no
* meaningful value.
*
* If the first element isn't tagged then it indicates the location of a
* managed object with a field that needs fixing up. In this case the second
* element of the pair is an object-relative offset to the field in question.
*/
typedef std::pair<uint32_t, uint32_t> AppImageReferenceOffsetInfo;
/*
* Tags the last bit. Used by AppImage logic to differentiate between pointers
* to managed objects and pointers to native reference arrays.
*/
template<typename T>
T SetDexCacheStringNativeRefTag(T val) {
static_assert(std::is_integral<T>::value, "Expected integral type.");
return val | 1u;
}
/*
* Tags the second last bit. Used by AppImage logic to differentiate between pointers
* to managed objects and pointers to native reference arrays.
*/
template<typename T>
T SetDexCachePreResolvedStringNativeRefTag(T val) {
static_assert(std::is_integral<T>::value, "Expected integral type.");
return val | 2u;
}
/*
* Retrieves the value of the last bit. Used by AppImage logic to
* differentiate between pointers to managed objects and pointers to native
* reference arrays.
*/
template<typename T>
bool HasDexCacheStringNativeRefTag(T val) {
static_assert(std::is_integral<T>::value, "Expected integral type.");
return (val & 1u) != 0u;
}
/*
* Retrieves the value of the second last bit. Used by AppImage logic to
* differentiate between pointers to managed objects and pointers to native
* reference arrays.
*/
template<typename T>
bool HasDexCachePreResolvedStringNativeRefTag(T val) {
static_assert(std::is_integral<T>::value, "Expected integral type.");
return (val & 2u) != 0u;
}
/*
* Sets the last bit of the value to 0. Used by AppImage logic to
* differentiate between pointers to managed objects and pointers to native
* reference arrays.
*/
template<typename T>
T ClearDexCacheNativeRefTags(T val) {
static_assert(std::is_integral<T>::value, "Expected integral type.");
return val & ~3u;
}
std::ostream& operator<<(std::ostream& os, const ImageHeader::ImageMethod& policy);
std::ostream& operator<<(std::ostream& os, const ImageHeader::ImageRoot& policy);
std::ostream& operator<<(std::ostream& os, const ImageHeader::ImageSections& section);
std::ostream& operator<<(std::ostream& os, const ImageSection& section);
std::ostream& operator<<(std::ostream& os, const ImageHeader::StorageMode& mode);
} // namespace art
#endif // ART_RUNTIME_IMAGE_H_