Merge "libsnapshot: No transition of snapuserd during second stage init" am: b5f0a3b73b (c42cac92) · Commits · e / os / android_system_core

fs_mgr/libsnapshot/snapshot.cpp

+30 −17

Original line number	Diff line number	Diff line
		@@ -1234,6 +1234,25 @@ bool SnapshotManager::OnSnapshotMergeComplete(LockedFile* lock, const std::strin
		return true;
		}

		static bool DeleteDmDevice(const std::string& name, const std::chrono::milliseconds& timeout_ms) {
		auto start = std::chrono::steady_clock::now();
		auto& dm = DeviceMapper::Instance();
		while (true) {
		if (dm.DeleteDeviceIfExists(name)) {
		break;
		}
		auto now = std::chrono::steady_clock::now();
		auto elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(now - start);
		if (elapsed >= timeout_ms) {
		LOG(ERROR) << "DeleteDevice timeout: " << name;
		return false;
		}
		std::this_thread::sleep_for(250ms);
		}

		return true;
		}

		bool SnapshotManager::CollapseSnapshotDevice(const std::string& name,
		const SnapshotStatus& status) {
		auto& dm = DeviceMapper::Instance();
		@@ -1292,10 +1311,11 @@ bool SnapshotManager::CollapseSnapshotDevice(const std::string& name,
		if (!dm.DeleteDeviceIfExists(base_name)) {
		LOG(ERROR) << "Unable to delete base device for snapshot: " << base_name;
		}
		auto source_name = GetSourceDeviceName(name);
		if (!dm.DeleteDeviceIfExists(source_name)) {
		LOG(ERROR) << "Unable to delete source device for snapshot: " << source_name;

		if (!DeleteDmDevice(GetSourceDeviceName(name), 4000ms)) {
		LOG(ERROR) << "Unable to delete source device for snapshot: " << GetSourceDeviceName(name);
		}

		return true;
		}

		@@ -1387,9 +1407,6 @@ bool SnapshotManager::PerformInitTransition(InitTransition transition,
		}

		auto misc_name = user_cow_name;
		if (transition == InitTransition::SELINUX_DETACH) {
		misc_name += "-selinux";
		}

		DmTable table;
		table.Emplace<DmTargetUser>(0, target.spec.length, misc_name);
		@@ -2122,15 +2139,12 @@ bool SnapshotManager::UnmapCowDevices(LockedFile* lock, const std::string& name)
		CHECK(lock);
		if (!EnsureImageManager()) return false;

		auto& dm = DeviceMapper::Instance();

		if (UpdateUsesCompression(lock) && !UnmapDmUserDevice(name)) {
		return false;
		}

		auto cow_name = GetCowName(name);
		if (!dm.DeleteDeviceIfExists(cow_name)) {
		LOG(ERROR) << "Cannot unmap " << cow_name;
		if (!DeleteDmDevice(GetCowName(name), 4000ms)) {
		LOG(ERROR) << "Cannot unmap: " << GetCowName(name);
		return false;
		}

		@@ -2155,13 +2169,12 @@ bool SnapshotManager::UnmapDmUserDevice(const std::string& snapshot_name) {
		return false;
		}

		if (!EnsureSnapuserdConnected()) {
		return false;
		}
		if (EnsureSnapuserdConnected()) {
		if (!snapuserd_client_->WaitForDeviceDelete(dm_user_name)) {
		LOG(ERROR) << "Failed to wait for " << dm_user_name << " control device to delete";
		return false;
		}
		}

		// Ensure the control device is gone so we don't run into ABA problems.
		auto control_device = "/dev/dm-user/" + dm_user_name;

fs_mgr/libsnapshot/snapuserd.cpp

+1 −1

Original line number	Diff line number	Diff line
		@@ -534,7 +534,7 @@ bool Snapuserd::ReadMetadata() {
		bool prev_copy_op = false;
		bool metadata_found = false;

		SNAP_LOG(DEBUG) << "ReadMetadata Start...";
		SNAP_LOG(DEBUG) << "ReadMetadata: Parsing cow file";

		if (!reader_->Parse(cow_fd_)) {
		SNAP_LOG(ERROR) << "Failed to parse";

fs_mgr/libsnapshot/snapuserd.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -70,6 +70,11 @@ class Snapuserd final {
		const std::string& GetMiscName() { return misc_name_; }
		uint64_t GetNumSectors() { return num_sectors_; }
		bool IsAttached() const { return ctrl_fd_ >= 0; }
		void CloseFds() {
		ctrl_fd_ = {};
		cow_fd_ = {};
		backing_store_fd_ = {};
		}

		private:
		bool DmuserReadRequest();

fs_mgr/libsnapshot/snapuserd_server.cpp

+2 −0

Original line number	Diff line number	Diff line
		@@ -210,6 +210,8 @@ void SnapuserdServer::RunThread(std::shared_ptr<DmUserHandler> handler) {
		}
		}

		handler->snapuserd()->CloseFds();

		auto misc_name = handler->misc_name();
		LOG(INFO) << "Handler thread about to exit: " << misc_name;

init/init.cpp

+0 −32

Original line number	Diff line number	Diff line
		@@ -723,37 +723,6 @@ void SendLoadPersistentPropertiesMessage() {
		}
		}

		static Result<void> TransitionSnapuserdAction(const BuiltinArguments&) {
		if (!SnapshotManager::IsSnapshotManagerNeeded() \|\|
		!android::base::GetBoolProperty(android::snapshot::kVirtualAbCompressionProp, false)) {
		return {};
		}

		auto sm = SnapshotManager::New();
		if (!sm) {
		LOG(FATAL) << "Failed to create SnapshotManager, will not transition snapuserd";
		return {};
		}

		ServiceList& service_list = ServiceList::GetInstance();
		auto svc = service_list.FindService("snapuserd");
		if (!svc) {
		LOG(FATAL) << "Failed to find snapuserd service, aborting transition";
		return {};
		}
		svc->Start();
		svc->SetShutdownCritical();

		if (!sm->PerformSecondStageInitTransition()) {
		LOG(FATAL) << "Failed to transition snapuserd to second-stage";
		}

		if (auto pid = GetSnapuserdFirstStagePid()) {
		KillFirstStageSnapuserd(pid.value());
		}
		return {};
		}

		int SecondStageMain(int argc, char** argv) {
		if (REBOOT_BOOTLOADER_ON_PANIC) {
		InstallRebootSignalHandlers();
		@@ -900,7 +869,6 @@ int SecondStageMain(int argc, char** argv) {

		// Queue an action that waits for coldboot done so we know ueventd has set up all of /dev...
		am.QueueBuiltinAction(wait_for_coldboot_done_action, "wait_for_coldboot_done");
		am.QueueBuiltinAction(TransitionSnapuserdAction, "TransitionSnapuserd");
		// ... so that we can start queuing up actions that require stuff from /dev.
		am.QueueBuiltinAction(SetMmapRndBitsAction, "SetMmapRndBits");
		Keychords keychords;