Merge "libsnapshot: Add a helper for handling data wipes in recovery." (ef8559f4) · Commits · e / os / android_system_core

fs_mgr/libsnapshot/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -72,6 +72,7 @@ filegroup {
		name: "libsnapshot_sources",
		srcs: [
		"android/snapshot/snapshot.proto",
		"device_info.cpp",
		"snapshot.cpp",
		"snapshot_metadata_updater.cpp",
		"partition_cow_creator.cpp",

fs_mgr/libsnapshot/device_info.cpp

0 → 100644

+123 −0

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		// Copyright (C) 2019 The Android Open Source Project
		//
		// Licensed under the Apache License, Version 2.0 (the "License");
		// you may not use this file except in compliance with the License.
		// You may obtain a copy of the License at
		//
		// http://www.apache.org/licenses/LICENSE-2.0
		//
		// Unless required by applicable law or agreed to in writing, software
		// distributed under the License is distributed on an "AS IS" BASIS,
		// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		// See the License for the specific language governing permissions and
		// limitations under the License.

		#include "device_info.h"

		#include <android-base/logging.h>
		#include <fs_mgr.h>
		#include <fs_mgr_overlayfs.h>

		namespace android {
		namespace snapshot {

		#ifdef LIBSNAPSHOT_USE_HAL
		using android::hardware::boot::V1_0::CommandResult;
		#endif

		using namespace std::string_literals;

		#ifdef __ANDROID_RECOVERY__
		constexpr bool kIsRecovery = true;
		#else
		constexpr bool kIsRecovery = false;
		#endif

		std::string DeviceInfo::GetGsidDir() const {
		return "ota"s;
		}

		std::string DeviceInfo::GetMetadataDir() const {
		return "/metadata/ota"s;
		}

		std::string DeviceInfo::GetSlotSuffix() const {
		return fs_mgr_get_slot_suffix();
		}

		std::string DeviceInfo::GetOtherSlotSuffix() const {
		return fs_mgr_get_other_slot_suffix();
		}

		const android::fs_mgr::IPartitionOpener& DeviceInfo::GetPartitionOpener() const {
		return opener_;
		}

		std::string DeviceInfo::GetSuperDevice(uint32_t slot) const {
		return fs_mgr_get_super_partition_name(slot);
		}

		bool DeviceInfo::IsOverlayfsSetup() const {
		return fs_mgr_overlayfs_is_setup();
		}

		#ifdef LIBSNAPSHOT_USE_HAL
		bool DeviceInfo::EnsureBootHal() {
		if (!boot_control_) {
		auto hal = android::hardware::boot::V1_0::IBootControl::getService();
		if (!hal) {
		LOG(ERROR) << "Could not find IBootControl HAL";
		return false;
		}
		boot_control_ = android::hardware::boot::V1_1::IBootControl::castFrom(hal);
		if (!boot_control_) {
		LOG(ERROR) << "Could not find IBootControl 1.1 HAL";
		return false;
		}
		}
		return true;
		}
		#endif

		bool DeviceInfo::SetBootControlMergeStatus([[maybe_unused]] MergeStatus status) {
		#ifdef LIBSNAPSHOT_USE_HAL
		if (!EnsureBootHal()) {
		return false;
		}
		if (!boot_control_->setSnapshotMergeStatus(status)) {
		LOG(ERROR) << "Unable to set the snapshot merge status";
		return false;
		}
		return true;
		#else
		LOG(ERROR) << "HAL support not enabled.";
		return false;
		#endif
		}

		bool DeviceInfo::IsRecovery() const {
		return kIsRecovery;
		}

		bool DeviceInfo::SetSlotAsUnbootable([[maybe_unused]] unsigned int slot) {
		#ifdef LIBSNAPSHOT_USE_HAL
		if (!EnsureBootHal()) {
		return false;
		}

		CommandResult result = {};
		auto cb = [&](CommandResult r) -> void { result = r; };
		boot_control_->setSlotAsUnbootable(slot, cb);
		if (!result.success) {
		LOG(ERROR) << "Error setting slot " << slot << " unbootable: " << result.errMsg;
		return false;
		}
		return true;
		#else
		LOG(ERROR) << "HAL support not enabled.";
		return false;
		#endif
		}

		} // namespace snapshot
		} // namespace android

fs_mgr/libsnapshot/device_info.h

0 → 100644

+53 −0

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		// Copyright (C) 2019 The Android Open Source Project
		//
		// Licensed under the Apache License, Version 2.0 (the "License");
		// you may not use this file except in compliance with the License.
		// You may obtain a copy of the License at
		//
		// http://www.apache.org/licenses/LICENSE-2.0
		//
		// Unless required by applicable law or agreed to in writing, software
		// distributed under the License is distributed on an "AS IS" BASIS,
		// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		// See the License for the specific language governing permissions and
		// limitations under the License.

		#pragma once

		#include <string>

		#ifdef LIBSNAPSHOT_USE_HAL
		#include <android/hardware/boot/1.1/IBootControl.h>
		#endif
		#include <liblp/partition_opener.h>
		#include <libsnapshot/snapshot.h>

		namespace android {
		namespace snapshot {

		class DeviceInfo final : public SnapshotManager::IDeviceInfo {
		using MergeStatus = android::hardware::boot::V1_1::MergeStatus;

		public:
		std::string GetGsidDir() const override;
		std::string GetMetadataDir() const override;
		std::string GetSlotSuffix() const override;
		std::string GetOtherSlotSuffix() const override;
		const android::fs_mgr::IPartitionOpener& GetPartitionOpener() const override;
		std::string GetSuperDevice(uint32_t slot) const override;
		bool IsOverlayfsSetup() const override;
		bool SetBootControlMergeStatus(MergeStatus status) override;
		bool SetSlotAsUnbootable(unsigned int slot) override;
		bool IsRecovery() const override;

		private:
		bool EnsureBootHal();

		android::fs_mgr::PartitionOpener opener_;
		#ifdef LIBSNAPSHOT_USE_HAL
		android::sp<android::hardware::boot::V1_1::IBootControl> boot_control_;
		#endif
		};

		} // namespace snapshot
		} // namespace android

fs_mgr/libsnapshot/include/libsnapshot/auto_device.h

+2 −0

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		@@ -27,6 +27,8 @@ struct AutoDevice {
		virtual ~AutoDevice(){};
		void Release();

		bool HasDevice() const { return !name_.empty(); }

		protected:
		AutoDevice(const std::string& name) : name_(name) {}
		std::string name_;

fs_mgr/libsnapshot/include/libsnapshot/snapshot.h

+26 −3

Original line number	Diff line number	Diff line
		@@ -122,6 +122,7 @@ class SnapshotManager final {
		virtual const IPartitionOpener& GetPartitionOpener() const = 0;
		virtual bool IsOverlayfsSetup() const = 0;
		virtual bool SetBootControlMergeStatus(MergeStatus status) = 0;
		virtual bool SetSlotAsUnbootable(unsigned int slot) = 0;
		virtual bool IsRecovery() const = 0;
		};

		@@ -133,7 +134,7 @@ class SnapshotManager final {
		static std::unique_ptr<SnapshotManager> New(IDeviceInfo* device = nullptr);

		// This is similar to New(), except designed specifically for first-stage
		// init.
		// init or recovery.
		static std::unique_ptr<SnapshotManager> NewForFirstStageMount(IDeviceInfo* device = nullptr);

		// Helper function for first-stage init to check whether a SnapshotManager
		@@ -180,7 +181,10 @@ class SnapshotManager final {
		//
		// MergeCompleted indicates that the update has fully completed.
		// GetUpdateState will return None, and a new update can begin.
		UpdateState ProcessUpdateState();
		//
		// The optional callback allows the caller to periodically check the
		// progress with GetUpdateState().
		UpdateState ProcessUpdateState(const std::function<void()>& callback = {});

		public:
		// Initiate the merge if necessary, then wait for the merge to finish.
		@@ -219,6 +223,18 @@ class SnapshotManager final {
		// call to CreateLogicalPartitions when snapshots are present.
		bool CreateLogicalAndSnapshotPartitions(const std::string& super_device);

		// This method should be called preceding any wipe or flash of metadata or
		// userdata. It is only valid in recovery.
		//
		// When userdata will be wiped or flashed, it is necessary to clean up any
		// snapshot state. If a merge is in progress, the merge must be finished.
		// If a snapshot is present but not yet merged, the slot must be marked as
		// unbootable.
		//
		// Returns true on success (or nothing to do), false on failure. The
		// optional callback fires periodically to query progress via GetUpdateState.
		bool HandleImminentDataWipe(const std::function<void()>& callback = {});

		// Dump debug information.
		bool Dump(std::ostream& os);

		@@ -231,7 +247,7 @@ class SnapshotManager final {
		// is not found in fstab.
		// Note: if this function is called the second time before the AutoDevice returned from the
		// first call is destroyed, the device will be unmounted when any of these AutoDevices is
		// destroyed. FOr example:
		// destroyed. For example:
		// auto a = mgr->EnsureMetadataMounted(); // mounts
		// auto b = mgr->EnsureMetadataMounted(); // does nothing
		// b.reset() // unmounts
		@@ -250,7 +266,10 @@ class SnapshotManager final {
		FRIEND_TEST(SnapshotTest, Merge);
		FRIEND_TEST(SnapshotTest, NoMergeBeforeReboot);
		FRIEND_TEST(SnapshotTest, UpdateBootControlHal);
		FRIEND_TEST(SnapshotUpdateTest, DataWipeAfterRollback);
		FRIEND_TEST(SnapshotUpdateTest, DataWipeRollbackInRecovery);
		FRIEND_TEST(SnapshotUpdateTest, MergeCannotRemoveCow);
		FRIEND_TEST(SnapshotUpdateTest, MergeInRecovery);
		FRIEND_TEST(SnapshotUpdateTest, SnapshotStatusFileWithoutCow);
		friend class SnapshotTest;
		friend class SnapshotUpdateTest;
		@@ -464,6 +483,10 @@ class SnapshotManager final {
		const LpMetadata* exported_target_metadata, const std::string& target_suffix,
		const std::map<std::string, SnapshotStatus>& all_snapshot_status);

		// Unmap all partitions that were mapped by CreateLogicalAndSnapshotPartitions.
		// This should only be called in recovery.
		bool UnmapAllPartitions();

		std::string gsid_dir_;
		std::string metadata_dir_;
		std::unique_ptr<IDeviceInfo> device_;