Merge "libdm, libsnapshot: Add a virtual interface for DeviceMapper." (5cd74158) · Commits · e / os / android_system_core

fs_mgr/libdm/include/libdm/dm.h

+34 −17

Original line number	Diff line number	Diff line
		@@ -55,7 +55,33 @@ static constexpr uint64_t kSectorSize = 512;
		// that prefix.
		std::optional<std::string> ExtractBlockDeviceName(const std::string& path);

		class DeviceMapper final {
		// This interface is for testing purposes. See DeviceMapper proper for what these methods do.
		class IDeviceMapper {
		public:
		virtual ~IDeviceMapper() {}

		struct TargetInfo {
		struct dm_target_spec spec;
		std::string data;
		TargetInfo() {}
		TargetInfo(const struct dm_target_spec& spec, const std::string& data)
		: spec(spec), data(data) {}

		bool IsOverflowSnapshot() const;
		};

		virtual bool CreateDevice(const std::string& name, const DmTable& table, std::string* path,
		const std::chrono::milliseconds& timeout_ms) = 0;
		virtual DmDeviceState GetState(const std::string& name) const = 0;
		virtual bool LoadTableAndActivate(const std::string& name, const DmTable& table) = 0;
		virtual bool GetTableInfo(const std::string& name, std::vector<TargetInfo>* table) = 0;
		virtual bool GetTableStatus(const std::string& name, std::vector<TargetInfo>* table) = 0;
		virtual bool GetDmDevicePathByName(const std::string& name, std::string* path) = 0;
		virtual bool GetDeviceString(const std::string& name, std::string* dev) = 0;
		virtual bool DeleteDeviceIfExists(const std::string& name) = 0;
		};

		class DeviceMapper final : public IDeviceMapper {
		public:
		class DmBlockDevice final {
		public:
		@@ -95,7 +121,7 @@ class DeviceMapper final {
		// Removes a device mapper device with the given name.
		// Returns 'true' on success, false otherwise.
		bool DeleteDevice(const std::string& name);
		bool DeleteDeviceIfExists(const std::string& name);
		bool DeleteDeviceIfExists(const std::string& name) override;
		// Removes a device mapper device with the given name and waits for \|timeout_ms\| milliseconds
		// for the corresponding block device to be deleted.
		bool DeleteDevice(const std::string& name, const std::chrono::milliseconds& timeout_ms);
		@@ -114,7 +140,7 @@ class DeviceMapper final {
		// Returns the current state of the underlying device mapper device
		// with given name.
		// One of INVALID, SUSPENDED or ACTIVE.
		DmDeviceState GetState(const std::string& name) const;
		DmDeviceState GetState(const std::string& name) const override;

		// Puts the given device to the specified status, which must be either:
		// - SUSPENDED: suspend the device, or
		@@ -158,7 +184,7 @@ class DeviceMapper final {
		// not \|path\| is available. It is the caller's responsibility to ensure
		// there are no races.
		bool CreateDevice(const std::string& name, const DmTable& table, std::string* path,
		const std::chrono::milliseconds& timeout_ms);
		const std::chrono::milliseconds& timeout_ms) override;

		// Create a device and activate the given table, without waiting to acquire
		// a valid path. If the caller will use GetDmDevicePathByName(), it should
		@@ -170,7 +196,7 @@ class DeviceMapper final {
		// process. A device with the given name must already exist.
		//
		// Returns 'true' on success, false otherwise.
		bool LoadTableAndActivate(const std::string& name, const DmTable& table);
		bool LoadTableAndActivate(const std::string& name, const DmTable& table) override;

		// Returns true if a list of available device mapper targets registered in the kernel was
		// successfully read and stored in 'targets'. Returns 'false' otherwise.
		@@ -216,7 +242,7 @@ class DeviceMapper final {

		// Returns a major:minor string for the named device-mapper node, that can
		// be used as inputs to DmTargets that take a block device.
		bool GetDeviceString(const std::string& name, std::string* dev);
		bool GetDeviceString(const std::string& name, std::string* dev) override;

		// The only way to create a DeviceMapper object.
		static DeviceMapper& Instance();
		@@ -231,20 +257,11 @@ class DeviceMapper final {
		// contain one TargetInfo for each target in the table. If the device does
		// not exist, or there were too many targets, the call will fail and return
		// false.
		struct TargetInfo {
		struct dm_target_spec spec;
		std::string data;
		TargetInfo() {}
		TargetInfo(const struct dm_target_spec& spec, const std::string& data)
		: spec(spec), data(data) {}

		bool IsOverflowSnapshot() const;
		};
		bool GetTableStatus(const std::string& name, std::vector<TargetInfo>* table);
		bool GetTableStatus(const std::string& name, std::vector<TargetInfo>* table) override;

		// Identical to GetTableStatus, except also retrives the active table for the device
		// mapper device from the kernel.
		bool GetTableInfo(const std::string& name, std::vector<TargetInfo>* table);
		bool GetTableInfo(const std::string& name, std::vector<TargetInfo>* table) override;

		static std::string GetTargetType(const struct dm_target_spec& spec);

fs_mgr/libfs_avb/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -152,6 +152,7 @@ cc_test {
		static_libs: [
		"libavb",
		"libdm",
		"libext2_uuid",
		"libfs_avb",
		"libfstab",
		],

fs_mgr/libsnapshot/device_info.cpp

+4 −0

Original line number	Diff line number	Diff line
		@@ -139,5 +139,9 @@ std::unique_ptr<android::fiemap::IImageManager> ISnapshotManager::IDeviceInfo::O
		}
		}

		android::dm::IDeviceMapper& DeviceInfo::GetDeviceMapper() {
		return android::dm::DeviceMapper::Instance();
		}

		} // namespace snapshot
		} // namespace android

fs_mgr/libsnapshot/device_info.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -40,6 +40,7 @@ class DeviceInfo final : public SnapshotManager::IDeviceInfo {
		bool IsRecovery() const override;
		std::unique_ptr<IImageManager> OpenImageManager() const override;
		bool IsFirstStageInit() const override;
		android::dm::IDeviceMapper& GetDeviceMapper() override;

		void set_first_stage_init(bool value) { first_stage_init_ = value; }

fs_mgr/libsnapshot/include/libsnapshot/snapshot.h

+11 −2

Original line number	Diff line number	Diff line
		@@ -110,6 +110,7 @@ class ISnapshotManager {
		virtual bool IsTestDevice() const { return false; }
		virtual bool IsFirstStageInit() const = 0;
		virtual std::unique_ptr<IImageManager> OpenImageManager() const = 0;
		virtual android::dm::IDeviceMapper& GetDeviceMapper() = 0;

		// Helper method for implementing OpenImageManager.
		std::unique_ptr<IImageManager> OpenImageManager(const std::string& gsid_dir) const;
		@@ -611,6 +612,14 @@ class SnapshotManager final : public ISnapshotManager {
		MergeFailureCode CheckMergeConsistency(LockedFile* lock, const std::string& name,
		const SnapshotStatus& update_status);

		// Get status or table information about a device-mapper node with a single target.
		enum class TableQuery {
		Table,
		Status,
		};
		bool GetSingleTarget(const std::string& dm_name, TableQuery query,
		android::dm::DeviceMapper::TargetInfo* target);

		// Interact with status files under /metadata/ota/snapshots.
		bool WriteSnapshotStatus(LockedFile* lock, const SnapshotStatus& status);
		bool ReadSnapshotStatus(LockedFile* lock, const std::string& name, SnapshotStatus* status);
		@@ -773,9 +782,9 @@ class SnapshotManager final : public ISnapshotManager {
		bool DeleteDeviceIfExists(const std::string& name,
		const std::chrono::milliseconds& timeout_ms = {});

		std::string gsid_dir_;
		std::string metadata_dir_;
		android::dm::IDeviceMapper& dm_;
		std::unique_ptr<IDeviceInfo> device_;
		std::string metadata_dir_;
		std::unique_ptr<IImageManager> images_;
		bool use_first_stage_snapuserd_ = false;
		bool in_factory_data_reset_ = false;