Merge "init: Support booting off GSIs installed to non-userdata block devices." (5aa37dc3) · Commits · e / os / android_system_core

fs_mgr/fs_mgr.cpp

+30 −8

Original line number	Diff line number	Diff line
		@@ -1602,6 +1602,14 @@ bool fs_mgr_load_verity_state(int* mode) {
		return true;
		}

		std::string fs_mgr_get_verity_device_name(const FstabEntry& entry) {
		if (entry.mount_point == "/") {
		// In AVB, the dm device name is vroot instead of system.
		return entry.fs_mgr_flags.avb ? "vroot" : "system";
		}
		return Basename(entry.mount_point);
		}

		bool fs_mgr_is_verity_enabled(const FstabEntry& entry) {
		if (!entry.fs_mgr_flags.verify && !entry.fs_mgr_flags.avb) {
		return false;
		@@ -1609,14 +1617,7 @@ bool fs_mgr_is_verity_enabled(const FstabEntry& entry) {

		DeviceMapper& dm = DeviceMapper::Instance();

		std::string mount_point;
		if (entry.mount_point == "/") {
		// In AVB, the dm device name is vroot instead of system.
		mount_point = entry.fs_mgr_flags.avb ? "vroot" : "system";
		} else {
		mount_point = Basename(entry.mount_point);
		}

		std::string mount_point = fs_mgr_get_verity_device_name(entry);
		if (dm.GetState(mount_point) == DmDeviceState::INVALID) {
		return false;
		}
		@@ -1639,6 +1640,27 @@ bool fs_mgr_is_verity_enabled(const FstabEntry& entry) {
		return false;
		}

		bool fs_mgr_verity_is_check_at_most_once(const android::fs_mgr::FstabEntry& entry) {
		if (!entry.fs_mgr_flags.verify && !entry.fs_mgr_flags.avb) {
		return false;
		}

		DeviceMapper& dm = DeviceMapper::Instance();
		std::string device = fs_mgr_get_verity_device_name(entry);

		std::vector<DeviceMapper::TargetInfo> table;
		if (dm.GetState(device) == DmDeviceState::INVALID \|\| !dm.GetTableInfo(device, &table)) {
		return false;
		}
		for (const auto& target : table) {
		if (strcmp(target.spec.target_type, "verity") == 0 &&
		target.data.find("check_at_most_once") != std::string::npos) {
		return true;
		}
		}
		return false;
		}

		std::string fs_mgr_get_super_partition_name(int slot) {
		// Devices upgrading to dynamic partitions are allowed to specify a super
		// partition name, assumed to be A/B (non-A/B retrofit is not supported).

fs_mgr/include/fs_mgr.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -77,6 +77,10 @@ bool fs_mgr_is_verity_enabled(const android::fs_mgr::FstabEntry& entry);
		bool fs_mgr_swapon_all(const android::fs_mgr::Fstab& fstab);
		bool fs_mgr_update_logical_partition(android::fs_mgr::FstabEntry* entry);

		// Returns true if the given fstab entry has verity enabled, and the verity
		// device is in "check_at_most_once" mode.
		bool fs_mgr_verity_is_check_at_most_once(const android::fs_mgr::FstabEntry& entry);

		int fs_mgr_do_format(const android::fs_mgr::FstabEntry& entry, bool reserve_footer);

		#define FS_MGR_SETUP_VERITY_SKIPPED (-3)

fs_mgr/tools/dmctl.cpp

+1 −1

Original line number	Diff line number	Diff line
		@@ -316,7 +316,7 @@ static int TableCmdHandler(int argc, char** argv) {

		DeviceMapper& dm = DeviceMapper::Instance();
		std::vector<DeviceMapper::TargetInfo> table;
		if (!dm.GetTableStatus(argv[0], &table)) {
		if (!dm.GetTableInfo(argv[0], &table)) {
		std::cerr << "Could not query table status of device \"" << argv[0] << "\"." << std::endl;
		return -EINVAL;
		}

init/first_stage_mount.cpp

+58 −24

Original line number	Diff line number	Diff line
		@@ -78,6 +78,7 @@ class FirstStageMount {
		ListenerAction HandleBlockDevice(const std::string& name, const Uevent&);
		bool InitRequiredDevices();
		bool InitMappedDevice(const std::string& verity_device);
		bool InitDeviceMapper();
		bool CreateLogicalPartitions();
		bool MountPartition(const Fstab::iterator& begin, bool erase_used_fstab_entry,
		Fstab::iterator* end = nullptr);
		@@ -97,6 +98,7 @@ class FirstStageMount {
		virtual bool SetUpDmVerity(FstabEntry* fstab_entry) = 0;

		bool need_dm_verity_;
		bool gsi_not_on_userdata_ = false;

		Fstab fstab_;
		std::string lp_metadata_partition_;
		@@ -267,8 +269,6 @@ bool FirstStageMount::GetDmLinearMetadataDevice() {
		}

		required_devices_partition_names_.emplace(super_partition_name_);
		// When booting from live GSI images, userdata is the super device.
		required_devices_partition_names_.emplace("userdata");
		return true;
		}

		@@ -281,25 +281,7 @@ bool FirstStageMount::InitRequiredDevices() {
		}

		if (IsDmLinearEnabled() \|\| need_dm_verity_) {
		const std::string dm_path = "/devices/virtual/misc/device-mapper";
		bool found = false;
		auto dm_callback = [this, &dm_path, &found](const Uevent& uevent) {
		if (uevent.path == dm_path) {
		device_handler_->HandleUevent(uevent);
		found = true;
		return ListenerAction::kStop;
		}
		return ListenerAction::kContinue;
		};
		uevent_listener_.RegenerateUeventsForPath("/sys" + dm_path, dm_callback);
		if (!found) {
		LOG(INFO) << "device-mapper device not found in /sys, waiting for its uevent";
		Timer t;
		uevent_listener_.Poll(dm_callback, 10s);
		LOG(INFO) << "Wait for device-mapper returned after " << t;
		}
		if (!found) {
		LOG(ERROR) << "device-mapper device not found after polling timeout";
		if (!InitDeviceMapper()) {
		return false;
		}
		}
		@@ -327,11 +309,36 @@ bool FirstStageMount::InitRequiredDevices() {
		return true;
		}

		bool FirstStageMount::InitDeviceMapper() {
		const std::string dm_path = "/devices/virtual/misc/device-mapper";
		bool found = false;
		auto dm_callback = [this, &dm_path, &found](const Uevent& uevent) {
		if (uevent.path == dm_path) {
		device_handler_->HandleUevent(uevent);
		found = true;
		return ListenerAction::kStop;
		}
		return ListenerAction::kContinue;
		};
		uevent_listener_.RegenerateUeventsForPath("/sys" + dm_path, dm_callback);
		if (!found) {
		LOG(INFO) << "device-mapper device not found in /sys, waiting for its uevent";
		Timer t;
		uevent_listener_.Poll(dm_callback, 10s);
		LOG(INFO) << "Wait for device-mapper returned after " << t;
		}
		if (!found) {
		LOG(ERROR) << "device-mapper device not found after polling timeout";
		return false;
		}
		return true;
		}

		bool FirstStageMount::InitDmLinearBackingDevices(const android::fs_mgr::LpMetadata& metadata) {
		auto partition_names = android::fs_mgr::GetBlockDevicePartitionNames(metadata);
		for (const auto& partition_name : partition_names) {
		const auto super_device = android::fs_mgr::GetMetadataSuperBlockDevice(metadata);
		if (partition_name == android::fs_mgr::GetBlockDevicePartitionName(*super_device)) {
		// The super partition was found in the earlier pass.
		if (partition_name == super_partition_name_) {
		continue;
		}
		required_devices_partition_names_.emplace(partition_name);
		@@ -499,6 +506,10 @@ bool FirstStageMount::TrySwitchSystemAsRoot() {
		if (system_partition == fstab_.end()) return true;

		if (MountPartition(system_partition, false)) {
		if (gsi_not_on_userdata_ && fs_mgr_verity_is_check_at_most_once(*system_partition)) {
		LOG(ERROR) << "check_most_at_once forbidden on external media";
		return false;
		}
		SwitchRoot("/system");
		} else {
		PLOG(ERROR) << "Failed to mount /system";
		@@ -612,7 +623,29 @@ void FirstStageMount::UseGsiIfPresent() {
		return;
		}

		if (!android::fs_mgr::CreateLogicalPartitions(*metadata.get(), "/dev/block/by-name/userdata")) {
		if (!InitDmLinearBackingDevices(*metadata.get())) {
		return;
		}

		// Device-mapper might not be ready if the device doesn't use DAP or verity
		// (for example, hikey).
		if (access("/dev/device-mapper", F_OK) && !InitDeviceMapper()) {
		return;
		}

		// Find the name of the super partition for the GSI. It will either be
		// "userdata", or a block device such as an sdcard. There are no by-name
		// partitions other than userdata that we support installing GSIs to.
		auto super = GetMetadataSuperBlockDevice(*metadata.get());
		std::string super_name = android::fs_mgr::GetBlockDevicePartitionName(*super);
		std::string super_path;
		if (super_name == "userdata") {
		super_path = "/dev/block/by-name/" + super_name;
		} else {
		super_path = "/dev/block/" + super_name;
		}

		if (!android::fs_mgr::CreateLogicalPartitions(*metadata.get(), super_path)) {
		LOG(ERROR) << "GSI partition layout could not be instantiated";
		return;
		}
		@@ -630,6 +663,7 @@ void FirstStageMount::UseGsiIfPresent() {
		fstab_.erase(system_partition);
		}
		fstab_.emplace_back(BuildGsiSystemFstabEntry());
		gsi_not_on_userdata_ = (super_name != "userdata");
		}

		bool FirstStageMountVBootV1::GetDmVerityDevices() {