Introduce VDEX file, use it for DEX files
This patch introduces a new output file called VDEX. In the future,
VDEX files will store pre-validated DEX files which do not need to be
re-extracted and re-verified when recompiling, e.g. due to new
profiling information or after a system update.
With this CL, the OatWriter writes DEX files into the VDEX and the
rest of its output into OAT. The OatFile class and related classes
are updated to load the VDEX at runtime and mmap the DEX file section
from it. Patchoat creates symlinks to the source VDEX files in the
target directory or copies the files if passed in as file descriptors.
The feature can be disabled by setting the environment variable
ART_ENABLE_VDEX to false.
Test: m test-art-host
Bug: 30937355
Change-Id: I54dcaececf6814c258c80524ec15e2e2ef69c8dd
diff --git a/runtime/oat_file.cc b/runtime/oat_file.cc
index 5752fd9..cbc5d3c 100644
--- a/runtime/oat_file.cc
+++ b/runtime/oat_file.cc
@@ -83,7 +83,8 @@
virtual ~OatFileBase() {}
template <typename kOatFileBaseSubType>
- static OatFileBase* OpenOatFile(const std::string& elf_filename,
+ static OatFileBase* OpenOatFile(const std::string& vdex_filename,
+ const std::string& elf_filename,
const std::string& location,
uint8_t* requested_base,
uint8_t* oat_file_begin,
@@ -101,6 +102,11 @@
virtual void PreLoad() = 0;
+ bool LoadVdex(const std::string& vdex_filename,
+ bool writable,
+ bool low_4gb,
+ std::string* error_msg);
+
virtual bool Load(const std::string& elf_filename,
uint8_t* oat_file_begin,
bool writable,
@@ -131,7 +137,8 @@
};
template <typename kOatFileBaseSubType>
-OatFileBase* OatFileBase::OpenOatFile(const std::string& elf_filename,
+OatFileBase* OatFileBase::OpenOatFile(const std::string& vdex_filename,
+ const std::string& elf_filename,
const std::string& location,
uint8_t* requested_base,
uint8_t* oat_file_begin,
@@ -144,6 +151,10 @@
ret->PreLoad();
+ if (kIsVdexEnabled && !ret->LoadVdex(vdex_filename, writable, low_4gb, error_msg)) {
+ return nullptr;
+ }
+
if (!ret->Load(elf_filename,
oat_file_begin,
writable,
@@ -166,6 +177,20 @@
return ret.release();
}
+bool OatFileBase::LoadVdex(const std::string& vdex_filename,
+ bool writable,
+ bool low_4gb,
+ std::string* error_msg) {
+ vdex_.reset(VdexFile::Open(vdex_filename, writable, low_4gb, error_msg));
+ if (vdex_.get() == nullptr) {
+ *error_msg = StringPrintf("Failed to load vdex file '%s' %s",
+ vdex_filename.c_str(),
+ error_msg->c_str());
+ return false;
+ }
+ return true;
+}
+
bool OatFileBase::ComputeFields(uint8_t* requested_base,
const std::string& file_path,
std::string* error_msg) {
@@ -321,29 +346,29 @@
dex_file_location.c_str());
return false;
}
- if (UNLIKELY(dex_file_offset > Size())) {
+ if (UNLIKELY(dex_file_offset > DexSize())) {
*error_msg = StringPrintf("In oat file '%s' found OatDexFile #%zu for '%s' with dex file "
"offset %u > %zu",
GetLocation().c_str(),
i,
dex_file_location.c_str(),
dex_file_offset,
- Size());
+ DexSize());
return false;
}
- if (UNLIKELY(Size() - dex_file_offset < sizeof(DexFile::Header))) {
+ if (UNLIKELY(DexSize() - dex_file_offset < sizeof(DexFile::Header))) {
*error_msg = StringPrintf("In oat file '%s' found OatDexFile #%zu for '%s' with dex file "
"offset %u of %zu but the size of dex file header is %zu",
GetLocation().c_str(),
i,
dex_file_location.c_str(),
dex_file_offset,
- Size(),
+ DexSize(),
sizeof(DexFile::Header));
return false;
}
- const uint8_t* dex_file_pointer = Begin() + dex_file_offset;
+ const uint8_t* dex_file_pointer = DexBegin() + dex_file_offset;
if (UNLIKELY(!DexFile::IsMagicValid(dex_file_pointer))) {
*error_msg = StringPrintf("In oat file '%s' found OatDexFile #%zu for '%s' with invalid "
"dex file magic '%s'",
@@ -363,7 +388,7 @@
return false;
}
const DexFile::Header* header = reinterpret_cast<const DexFile::Header*>(dex_file_pointer);
- if (Size() - dex_file_offset < header->file_size_) {
+ if (DexSize() - dex_file_offset < header->file_size_) {
*error_msg = StringPrintf("In oat file '%s' found OatDexFile #%zu for '%s' with dex file "
"offset %u and size %u truncated at %zu",
GetLocation().c_str(),
@@ -371,7 +396,7 @@
dex_file_location.c_str(),
dex_file_offset,
header->file_size_,
- Size());
+ DexSize());
return false;
}
@@ -942,31 +967,37 @@
: nullptr;
}
-OatFile* OatFile::Open(const std::string& filename,
- const std::string& location,
+OatFile* OatFile::Open(const std::string& oat_filename,
+ const std::string& oat_location,
uint8_t* requested_base,
uint8_t* oat_file_begin,
bool executable,
bool low_4gb,
const char* abs_dex_location,
std::string* error_msg) {
- ScopedTrace trace("Open oat file " + location);
- CHECK(!filename.empty()) << location;
- CheckLocation(location);
+ ScopedTrace trace("Open oat file " + oat_location);
+ CHECK(!oat_filename.empty()) << oat_location;
+ CheckLocation(oat_location);
- // Check that the file even exists, fast-fail.
- if (!OS::FileExists(filename.c_str())) {
- *error_msg = StringPrintf("File %s does not exist.", filename.c_str());
+ std::string vdex_filename = ReplaceFileExtension(oat_filename, "vdex");
+
+ // Check that the files even exist, fast-fail.
+ if (kIsVdexEnabled && !OS::FileExists(vdex_filename.c_str())) {
+ *error_msg = StringPrintf("File %s does not exist.", vdex_filename.c_str());
+ return nullptr;
+ } else if (!OS::FileExists(oat_filename.c_str())) {
+ *error_msg = StringPrintf("File %s does not exist.", oat_filename.c_str());
return nullptr;
}
// Try dlopen first, as it is required for native debuggability. This will fail fast if dlopen is
// disabled.
- OatFile* with_dlopen = OatFileBase::OpenOatFile<DlOpenOatFile>(filename,
- location,
+ OatFile* with_dlopen = OatFileBase::OpenOatFile<DlOpenOatFile>(vdex_filename,
+ oat_filename,
+ oat_location,
requested_base,
oat_file_begin,
- false,
+ false /* writable */,
executable,
low_4gb,
abs_dex_location,
@@ -975,7 +1006,7 @@
return with_dlopen;
}
if (kPrintDlOpenErrorMessage) {
- LOG(ERROR) << "Failed to dlopen: " << filename << " with error " << *error_msg;
+ LOG(ERROR) << "Failed to dlopen: " << oat_filename << " with error " << *error_msg;
}
// If we aren't trying to execute, we just use our own ElfFile loader for a couple reasons:
//
@@ -990,11 +1021,12 @@
//
// Another independent reason is the absolute placement of boot.oat. dlopen on the host usually
// does honor the virtual address encoded in the ELF file only for ET_EXEC files, not ET_DYN.
- OatFile* with_internal = OatFileBase::OpenOatFile<ElfOatFile>(filename,
- location,
+ OatFile* with_internal = OatFileBase::OpenOatFile<ElfOatFile>(vdex_filename,
+ oat_filename,
+ oat_location,
requested_base,
oat_file_begin,
- false,
+ false /* writable */,
executable,
low_4gb,
abs_dex_location,
@@ -1036,6 +1068,7 @@
OatFile::OatFile(const std::string& location, bool is_executable)
: location_(location),
+ vdex_(nullptr),
begin_(nullptr),
end_(nullptr),
bss_begin_(nullptr),
@@ -1071,6 +1104,14 @@
return bss_end_;
}
+const uint8_t* OatFile::DexBegin() const {
+ return kIsVdexEnabled ? vdex_->Begin() : Begin();
+}
+
+const uint8_t* OatFile::DexEnd() const {
+ return kIsVdexEnabled ? vdex_->End() : End();
+}
+
const OatFile::OatDexFile* OatFile::GetOatDexFile(const char* dex_location,
const uint32_t* dex_location_checksum,
std::string* error_msg) const {