Merge "init: Add first-stage init support for snapshot-based partitions." (7309acb5) · Commits · e / os / android_system_core

init/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -70,6 +70,7 @@ cc_defaults {
		"libprotobuf-cpp-lite",
		"libpropertyinfoserializer",
		"libpropertyinfoparser",
		"libsnapshot_nobinder",
		],
		shared_libs: [
		"libbacktrace",

init/Android.mk

+1 −0

Original line number	Diff line number	Diff line
		@@ -114,6 +114,7 @@ LOCAL_STATIC_LIBRARIES := \
		libbacktrace \
		libmodprobe \
		libext2_uuid \
		libsnapshot_nobinder \

		LOCAL_SANITIZE := signed-integer-overflow
		# First stage init is weird: it may start without stdout/stderr, and no /proc.

init/first_stage_mount.cpp

+24 −10

Original line number	Diff line number	Diff line
		@@ -36,6 +36,7 @@
		#include <fs_mgr_overlayfs.h>
		#include <libgsi/libgsi.h>
		#include <liblp/liblp.h>
		#include <libsnapshot/snapshot.h>

		#include "devices.h"
		#include "switch_root.h"
		@@ -55,6 +56,7 @@ using android::fs_mgr::FstabEntry;
		using android::fs_mgr::ReadDefaultFstab;
		using android::fs_mgr::ReadFstabFromDt;
		using android::fs_mgr::SkipMountingPartitions;
		using android::snapshot::SnapshotManager;

		using namespace std::literals;

		@@ -244,8 +246,6 @@ bool FirstStageMount::DoFirstStageMount() {

		if (!InitDevices()) return false;

		if (!CreateLogicalPartitions()) return false;

		if (!MountPartitions()) return false;

		return true;
		@@ -366,6 +366,16 @@ bool FirstStageMount::CreateLogicalPartitions() {
		return false;
		}

		if (SnapshotManager::IsSnapshotManagerNeeded()) {
		auto sm = SnapshotManager::NewForFirstStageMount();
		if (!sm) {
		return false;
		}
		if (sm->NeedSnapshotsInFirstStageMount()) {
		return sm->CreateLogicalAndSnapshotPartitions(lp_metadata_partition_);
		}
		}

		auto metadata = android::fs_mgr::ReadCurrentMetadata(lp_metadata_partition_);
		if (!metadata) {
		LOG(ERROR) << "Could not read logical partition metadata from " << lp_metadata_partition_;
		@@ -493,14 +503,7 @@ bool FirstStageMount::MountPartition(const Fstab::iterator& begin, bool erase_sa
		// this case, we mount system first then pivot to it. From that point on,
		// we are effectively identical to a system-as-root device.
		bool FirstStageMount::TrySwitchSystemAsRoot() {
		auto metadata_partition = std::find_if(fstab_.begin(), fstab_.end(), [](const auto& entry) {
		return entry.mount_point == "/metadata";
		});
		if (metadata_partition != fstab_.end()) {
		if (MountPartition(metadata_partition, true /* erase_same_mounts */)) {
		UseGsiIfPresent();
		}
		}

		auto system_partition = std::find_if(fstab_.begin(), fstab_.end(), [](const auto& entry) {
		return entry.mount_point == "/system";
		@@ -523,6 +526,17 @@ bool FirstStageMount::TrySwitchSystemAsRoot() {
		}

		bool FirstStageMount::MountPartitions() {
		// Mount /metadata before creating logical partitions, since we need to
		// know whether a snapshot merge is in progress.
		auto metadata_partition = std::find_if(fstab_.begin(), fstab_.end(), [](const auto& entry) {
		return entry.mount_point == "/metadata";
		});
		if (metadata_partition != fstab_.end()) {
		MountPartition(metadata_partition, true /* erase_same_mounts */);
		}

		if (!CreateLogicalPartitions()) return false;

		if (!TrySwitchSystemAsRoot()) return false;

		if (!SkipMountingPartitions(&fstab_)) return false;