Merge "Set block size in dm-bow" into rvc-dev (5ec1865b) · Commits · e / os / android_system_core

fs_mgr/fs_mgr.cpp

+22 −2

Original line number	Diff line number	Diff line
		@@ -1120,8 +1120,28 @@ class CheckpointManager {
		}

		android::dm::DmTable table;
		if (!table.AddTarget(std::make_unique<android::dm::DmTargetBow>(
		0, size, entry->blk_device))) {
		auto bowTarget =
		std::make_unique<android::dm::DmTargetBow>(0, size, entry->blk_device);

		// dm-bow uses the first block as a log record, and relocates the real first block
		// elsewhere. For metadata encrypted devices, dm-bow sits below dm-default-key, and
		// for post Android Q devices dm-default-key uses a block size of 4096 always.
		// So if dm-bow's block size, which by default is the block size of the underlying
		// hardware, is less than dm-default-key's, blocks will get broken up and I/O will
		// fail as it won't be data_unit_size aligned.
		// However, since it is possible there is an already shipping non
		// metadata-encrypted device with smaller blocks, we must not change this for
		// devices shipped with Q or earlier unless they explicitly selected dm-default-key
		// v2
		constexpr unsigned int pre_gki_level = __ANDROID_API_Q__;
		unsigned int options_format_version = android::base::GetUintProperty<unsigned int>(
		"ro.crypto.dm_default_key.options_format.version",
		(android::fscrypt::GetFirstApiLevel() <= pre_gki_level ? 1 : 2));
		if (options_format_version > 1) {
		bowTarget->SetBlockSize(4096);
		}

		if (!table.AddTarget(std::move(bowTarget))) {
		LERROR << "Failed to add bow target";
		return false;
		}

+5 −0

Original line number	Diff line number	Diff line
		@@ -120,6 +120,11 @@ std::string DmTargetAndroidVerity::GetParameterString() const {
		return keyid_ + " " + block_device_;
		}

		std::string DmTargetBow::GetParameterString() const {
		if (!block_size_) return target_string_;
		return target_string_ + " 1 block_size:" + std::to_string(block_size_);
		}

		std::string DmTargetSnapshot::name() const {
		if (mode_ == SnapshotStorageMode::Merge) {
		return "snapshot-merge";

+4 −1

Original line number	Diff line number	Diff line
		@@ -175,11 +175,14 @@ class DmTargetBow final : public DmTarget {
		DmTargetBow(uint64_t start, uint64_t length, const std::string& target_string)
		: DmTarget(start, length), target_string_(target_string) {}

		void SetBlockSize(uint32_t block_size) { block_size_ = block_size; }

		std::string name() const override { return "bow"; }
		std::string GetParameterString() const override { return target_string_; }
		std::string GetParameterString() const override;

		private:
		std::string target_string_;
		uint32_t block_size_ = 0;
		};

		enum class SnapshotStorageMode {