liblp: UpdateMetadataForInPlaceSnapshot (293cd027) · Commits · e / os / android_system_core

fs_mgr/liblp/builder.cpp

+7 −0

Original line number	Original line	Diff line number	Diff line
	@@ -171,6 +171,13 @@ std::unique_ptr<MetadataBuilder> MetadataBuilder::NewForUpdate(const IPartitionO
	}		}
	}		}

			if (IPropertyFetcher::GetInstance()->GetBoolProperty("ro.virtual_ab.enabled", false)) {
			if (!UpdateMetadataForInPlaceSnapshot(metadata.get(), source_slot_number,
			target_slot_number)) {
			return nullptr;
			}
			}

	return New(*metadata.get(), &opener);		return New(*metadata.get(), &opener);
	}		}

fs_mgr/liblp/utility.cpp

+77 −0

Original line number	Original line	Diff line number	Diff line
	@@ -24,6 +24,10 @@
	#include <sys/ioctl.h>		#include <sys/ioctl.h>
	#endif		#endif

			#include <map>
			#include <string>
			#include <vector>

	#include <android-base/file.h>		#include <android-base/file.h>
	#include <ext4_utils/ext4_utils.h>		#include <ext4_utils/ext4_utils.h>
	#include <openssl/sha.h>		#include <openssl/sha.h>
	@@ -182,6 +186,14 @@ bool UpdatePartitionGroupName(LpMetadataPartitionGroup* group, const std::string
	return true;		return true;
	}		}

			bool UpdatePartitionName(LpMetadataPartition* partition, const std::string& name) {
			if (name.size() > sizeof(partition->name)) {
			return false;
			}
			strncpy(partition->name, name.c_str(), sizeof(partition->name));
			return true;
			}

	bool SetBlockReadonly(int fd, bool readonly) {		bool SetBlockReadonly(int fd, bool readonly) {
	#if defined(__linux__)		#if defined(__linux__)
	int val = readonly;		int val = readonly;
	@@ -207,5 +219,70 @@ base::unique_fd GetControlFileOrOpen(const char* path, int flags) {
	return base::unique_fd(open(path, flags));		return base::unique_fd(open(path, flags));
	}		}

			bool UpdateMetadataForInPlaceSnapshot(LpMetadata* metadata, uint32_t source_slot_number,
			uint32_t target_slot_number) {
			std::string source_slot_suffix = SlotSuffixForSlotNumber(source_slot_number);
			std::string target_slot_suffix = SlotSuffixForSlotNumber(target_slot_number);

			// There can be leftover groups with target suffix on retrofit devices.
			// They are useless now, so delete.
			std::vector<LpMetadataPartitionGroup*> new_group_ptrs;
			for (auto& group : metadata->groups) {
			std::string group_name = GetPartitionGroupName(group);
			std::string slot_suffix = GetPartitionSlotSuffix(group_name);
			// Don't add groups with target slot suffix.
			if (slot_suffix == target_slot_suffix) continue;
			// Replace source slot suffix with target slot suffix.
			if (slot_suffix == source_slot_suffix) {
			std::string new_name = group_name.substr(0, group_name.size() - slot_suffix.size()) +
			target_slot_suffix;
			if (!UpdatePartitionGroupName(&group, new_name)) {
			LERROR << "Group name too long: " << new_name;
			return false;
			}
			}
			new_group_ptrs.push_back(&group);
			}

			std::vector<LpMetadataPartition*> new_partition_ptrs;
			for (auto& partition : metadata->partitions) {
			std::string partition_name = GetPartitionName(partition);
			std::string slot_suffix = GetPartitionSlotSuffix(partition_name);
			// Don't add partitions with target slot suffix.
			if (slot_suffix == target_slot_suffix) continue;
			// Replace source slot suffix with target slot suffix.
			if (slot_suffix == source_slot_suffix) {
			std::string new_name =
			partition_name.substr(0, partition_name.size() - slot_suffix.size()) +
			target_slot_suffix;
			if (!UpdatePartitionName(&partition, new_name)) {
			LERROR << "Partition name too long: " << new_name;
			return false;
			}
			}
			// Update group index.
			auto it = std::find(new_group_ptrs.begin(), new_group_ptrs.end(),
			&metadata->groups[partition.group_index]);
			if (it == new_group_ptrs.end()) {
			LWARN << "Removing partition " << partition_name << " from group "
			<< GetPartitionGroupName(metadata->groups[partition.group_index])
			<< "; this partition should not belong to this group!";
			continue; // not adding to new_partition_ptrs
			}
			partition.group_index = std::distance(new_group_ptrs.begin(), it);
			new_partition_ptrs.push_back(&partition);
			}

			std::vector<LpMetadataPartition> new_partitions;
			for (auto* p : new_partition_ptrs) new_partitions.emplace_back(std::move(*p));
			metadata->partitions = std::move(new_partitions);

			std::vector<LpMetadataPartitionGroup> new_groups;
			for (auto* g : new_group_ptrs) new_groups.emplace_back(std::move(*g));
			metadata->groups = std::move(new_groups);

			return true;
			}

	} // namespace fs_mgr		} // namespace fs_mgr
	} // namespace android		} // namespace android

fs_mgr/liblp/utility.h

+5 −0

Original line number	Original line	Diff line number	Diff line
	@@ -89,12 +89,17 @@ constexpr uint64_t AlignTo(uint64_t base, uint32_t alignment, uint32_t alignment
	// Update names from C++ strings.		// Update names from C++ strings.
	bool UpdateBlockDevicePartitionName(LpMetadataBlockDevice* device, const std::string& name);		bool UpdateBlockDevicePartitionName(LpMetadataBlockDevice* device, const std::string& name);
	bool UpdatePartitionGroupName(LpMetadataPartitionGroup* group, const std::string& name);		bool UpdatePartitionGroupName(LpMetadataPartitionGroup* group, const std::string& name);
			bool UpdatePartitionName(LpMetadataPartition* partition, const std::string& name);

	// Call BLKROSET ioctl on fd so that fd is readonly / read-writable.		// Call BLKROSET ioctl on fd so that fd is readonly / read-writable.
	bool SetBlockReadonly(int fd, bool readonly);		bool SetBlockReadonly(int fd, bool readonly);

	::android::base::unique_fd GetControlFileOrOpen(const char* path, int flags);		::android::base::unique_fd GetControlFileOrOpen(const char* path, int flags);

			// For Virtual A/B updates, modify \|metadata\| so that it can be written to \|target_slot_number\|.
			bool UpdateMetadataForInPlaceSnapshot(LpMetadata* metadata, uint32_t source_slot_number,
			uint32_t target_slot_number);

	} // namespace fs_mgr		} // namespace fs_mgr
	} // namespace android		} // namespace android

fs_mgr/liblp/utility_test.cpp

+79 −0

Original line number	Original line	Diff line number	Diff line
	@@ -15,6 +15,7 @@
	*/		*/

	#include <gtest/gtest.h>		#include <gtest/gtest.h>
			#include <liblp/builder.h>
	#include <liblp/liblp.h>		#include <liblp/liblp.h>

	#include "utility.h"		#include "utility.h"
	@@ -75,3 +76,81 @@ TEST(liblp, GetPartitionSlotSuffix) {
	EXPECT_EQ(GetPartitionSlotSuffix("system_a"), "_a");		EXPECT_EQ(GetPartitionSlotSuffix("system_a"), "_a");
	EXPECT_EQ(GetPartitionSlotSuffix("system_b"), "_b");		EXPECT_EQ(GetPartitionSlotSuffix("system_b"), "_b");
	}		}

			namespace android {
			namespace fs_mgr {
			// Equality comparison for testing. In reality, equality of device_index doesn't
			// necessary mean equality of the block device.
			bool operator==(const LinearExtent& l, const LinearExtent& r) {
			return l.device_index() == r.device_index() && l.physical_sector() == r.physical_sector() &&
			l.end_sector() == r.end_sector();
			}
			} // namespace fs_mgr
			} // namespace android

			static std::vector<LinearExtent> GetPartitionExtents(Partition* p) {
			std::vector<LinearExtent> extents;
			for (auto&& extent : p->extents()) {
			auto linear_extent = extent->AsLinearExtent();
			if (!linear_extent) return {};
			extents.push_back(*linear_extent);
			}
			return extents;
			}

			TEST(liblp, UpdateMetadataForInPlaceSnapshot) {
			using std::unique_ptr;

			unique_ptr<MetadataBuilder> builder = MetadataBuilder::New(1024 * 1024, 1024, 2);
			ASSERT_NE(builder, nullptr);

			ASSERT_TRUE(builder->AddGroup("group_a", 256 * 1024));
			Partition* system_a = builder->AddPartition("system_a", "group_a", LP_PARTITION_ATTR_READONLY);
			ASSERT_NE(system_a, nullptr);
			ASSERT_TRUE(builder->ResizePartition(system_a, 40 * 1024));
			Partition* vendor_a = builder->AddPartition("vendor_a", "group_a", LP_PARTITION_ATTR_READONLY);
			ASSERT_NE(vendor_a, nullptr);
			ASSERT_TRUE(builder->ResizePartition(vendor_a, 20 * 1024));

			ASSERT_TRUE(builder->AddGroup("group_b", 258 * 1024));
			Partition* system_b = builder->AddPartition("system_b", "group_b", LP_PARTITION_ATTR_READONLY);
			ASSERT_NE(system_b, nullptr);
			ASSERT_TRUE(builder->ResizePartition(system_b, 36 * 1024));
			Partition* vendor_b = builder->AddPartition("vendor_b", "group_b", LP_PARTITION_ATTR_READONLY);
			ASSERT_NE(vendor_b, nullptr);
			ASSERT_TRUE(builder->ResizePartition(vendor_b, 32 * 1024));

			auto system_a_extents = GetPartitionExtents(system_a);
			ASSERT_FALSE(system_a_extents.empty());

			auto vendor_a_extents = GetPartitionExtents(vendor_a);
			ASSERT_FALSE(vendor_a_extents.empty());

			auto metadata = builder->Export();
			ASSERT_NE(nullptr, metadata);

			ASSERT_TRUE(UpdateMetadataForInPlaceSnapshot(metadata.get(), 0, 1));

			auto new_builder = MetadataBuilder::New(*metadata);
			ASSERT_NE(nullptr, new_builder);

			EXPECT_EQ(nullptr, new_builder->FindGroup("group_a"));
			EXPECT_EQ(nullptr, new_builder->FindPartition("system_a"));
			EXPECT_EQ(nullptr, new_builder->FindPartition("vendor_a"));

			auto group_b = new_builder->FindGroup("group_b");
			ASSERT_NE(nullptr, group_b);
			ASSERT_EQ(256 * 1024, group_b->maximum_size());

			auto new_system_b = new_builder->FindPartition("system_b");
			ASSERT_NE(nullptr, new_system_b);
			EXPECT_EQ(40 * 1024, new_system_b->size());
			auto new_system_b_extents = GetPartitionExtents(new_system_b);
			EXPECT_EQ(system_a_extents, new_system_b_extents);

			auto new_vendor_b = new_builder->FindPartition("vendor_b");
			ASSERT_NE(nullptr, new_vendor_b);
			EXPECT_EQ(20 * 1024, new_vendor_b->size());
			auto new_vendor_b_extents = GetPartitionExtents(new_vendor_b);
			EXPECT_EQ(vendor_a_extents, new_vendor_b_extents);
			}