Merge "Add VerifyMergeOps to ISnapshotWriter" (3ad79c8f) · Commits · e / os / android_system_core

fs_mgr/libsnapshot/cow_reader.cpp

+2 −2

Original line number	Diff line number	Diff line
		@@ -231,7 +231,7 @@ bool CowReader::ParseOps(std::optional<uint64_t> label) {
		memcpy(&footer_->op, &current_op, sizeof(footer->op));
		off_t offs = lseek(fd_.get(), pos, SEEK_SET);
		if (offs < 0 \|\| pos != static_cast<uint64_t>(offs)) {
		PLOG(ERROR) << "lseek next op failed";
		PLOG(ERROR) << "lseek next op failed " << offs;
		return false;
		}
		if (!android::base::ReadFully(fd_, &footer->data, sizeof(footer->data))) {
		@@ -251,7 +251,7 @@ bool CowReader::ParseOps(std::optional<uint64_t> label) {
		// Position for next cluster read
		off_t offs = lseek(fd_.get(), pos, SEEK_SET);
		if (offs < 0 \|\| pos != static_cast<uint64_t>(offs)) {
		PLOG(ERROR) << "lseek next op failed";
		PLOG(ERROR) << "lseek next op failed " << offs;
		return false;
		}
		ops_buffer->resize(current_op_num);

fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot_writer.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -44,6 +44,7 @@ class MockSnapshotWriter : public ISnapshotWriter {

		// Open the writer in write mode (no append).
		MOCK_METHOD(bool, Initialize, (), (override));
		MOCK_METHOD(bool, VerifyMergeOps, (), (override, const, noexcept));

		// Open the writer in append mode, with the last label to resume
		// from. See CowWriter::InitializeAppend.

fs_mgr/libsnapshot/include/libsnapshot/snapshot_writer.h

+9 −2

Original line number	Diff line number	Diff line
		@@ -47,6 +47,7 @@ class ISnapshotWriter : public ICowWriter {
		virtual bool InitializeAppend(uint64_t label) = 0;

		virtual std::unique_ptr<FileDescriptor> OpenReader() = 0;
		virtual bool VerifyMergeOps() const noexcept = 0;

		protected:
		android::base::borrowed_fd GetSourceFd();
		@@ -58,7 +59,7 @@ class ISnapshotWriter : public ICowWriter {
		};

		// Send writes to a COW or a raw device directly, based on a threshold.
		class CompressedSnapshotWriter : public ISnapshotWriter {
		class CompressedSnapshotWriter final : public ISnapshotWriter {
		public:
		CompressedSnapshotWriter(const CowOptions& options);

		@@ -70,6 +71,7 @@ class CompressedSnapshotWriter : public ISnapshotWriter {
		bool Finalize() override;
		uint64_t GetCowSize() override;
		std::unique_ptr<FileDescriptor> OpenReader() override;
		bool VerifyMergeOps() const noexcept;

		protected:
		bool EmitCopy(uint64_t new_block, uint64_t old_block) override;
		@@ -81,13 +83,14 @@ class CompressedSnapshotWriter : public ISnapshotWriter {
		bool EmitSequenceData(size_t num_ops, const uint32_t* data) override;

		private:
		std::unique_ptr<CowReader> OpenCowReader() const;
		android::base::unique_fd cow_device_;

		std::unique_ptr<CowWriter> cow_;
		};

		// Write directly to a dm-snapshot device.
		class OnlineKernelSnapshotWriter : public ISnapshotWriter {
		class OnlineKernelSnapshotWriter final : public ISnapshotWriter {
		public:
		OnlineKernelSnapshotWriter(const CowOptions& options);

		@@ -101,6 +104,10 @@ class OnlineKernelSnapshotWriter : public ISnapshotWriter {
		uint64_t GetCowSize() override { return cow_size_; }
		std::unique_ptr<FileDescriptor> OpenReader() override;

		// Online kernel snapshot writer doesn't care about merge sequences.
		// So ignore.
		bool VerifyMergeOps() const noexcept override { return true; }

		protected:
		bool EmitRawBlocks(uint64_t new_block_start, const void* data, size_t size) override;
		bool EmitZeroBlocks(uint64_t new_block_start, uint64_t num_blocks) override;

fs_mgr/libsnapshot/snapshot_writer.cpp

+15 −1

Original line number	Diff line number	Diff line
		@@ -67,7 +67,7 @@ uint64_t CompressedSnapshotWriter::GetCowSize() {
		return cow_->GetCowSize();
		}

		std::unique_ptr<FileDescriptor> CompressedSnapshotWriter::OpenReader() {
		std::unique_ptr<CowReader> CompressedSnapshotWriter::OpenCowReader() const {
		unique_fd cow_fd(dup(cow_device_.get()));
		if (cow_fd < 0) {
		PLOG(ERROR) << "dup COW device";
		@@ -79,6 +79,20 @@ std::unique_ptr<FileDescriptor> CompressedSnapshotWriter::OpenReader() {
		LOG(ERROR) << "Unable to read COW";
		return nullptr;
		}
		return cow;
		}

		bool CompressedSnapshotWriter::VerifyMergeOps() const noexcept {
		auto cow_reader = OpenCowReader();
		if (cow_reader == nullptr) {
		LOG(ERROR) << "Couldn't open CowReader";
		return false;
		}
		return cow_reader->VerifyMergeOps();
		}

		std::unique_ptr<FileDescriptor> CompressedSnapshotWriter::OpenReader() {
		auto cow = OpenCowReader();

		auto reader = std::make_unique<CompressedSnapshotReader>();
		if (!reader->SetCow(std::move(cow))) {