Merge "userdata_checkpoint_remount: delete all devices in dm-stack under /data" (da776c39) · Commits · e / os / android_system_core

fs_mgr/fs_mgr.cpp

+46 −17

Original line number	Diff line number	Diff line
		@@ -91,6 +91,7 @@
		#define ARRAY_SIZE(a) (sizeof(a) / sizeof(*(a)))

		using android::base::Basename;
		using android::base::GetBoolProperty;
		using android::base::Realpath;
		using android::base::StartsWith;
		using android::base::unique_fd;
		@@ -1357,14 +1358,33 @@ int fs_mgr_umount_all(android::fs_mgr::Fstab* fstab) {
		return ret;
		}

		static std::string GetBlockDeviceForMountPoint(const std::string& mount_point) {
		Fstab mounts;
		if (!ReadFstabFromFile("/proc/mounts", &mounts)) {
		LERROR << "Can't read /proc/mounts";
		return "";
		}
		auto entry = GetEntryForMountPoint(&mounts, mount_point);
		if (entry == nullptr) {
		LWARNING << mount_point << " is not mounted";
		return "";
		}
		return entry->blk_device;
		}

		// TODO(b/143970043): return different error codes based on which step failed.
		int fs_mgr_remount_userdata_into_checkpointing(Fstab* fstab) {
		auto entry = GetMountedEntryForUserdata(fstab);
		if (entry == nullptr) {
		std::string block_device = GetBlockDeviceForMountPoint("/data");
		if (block_device.empty()) {
		LERROR << "/data is not mounted";
		return -1;
		}
		auto fstab_entry = GetMountedEntryForUserdata(fstab);
		if (fstab_entry == nullptr) {
		LERROR << "Can't find /data in fstab";
		return -1;
		}
		if (!entry->fs_mgr_flags.checkpoint_blk && !entry->fs_mgr_flags.checkpoint_fs) {
		if (!fstab_entry->fs_mgr_flags.checkpoint_blk && !fstab_entry->fs_mgr_flags.checkpoint_fs) {
		LINFO << "Userdata doesn't support checkpointing. Nothing to do";
		return 0;
		}
		@@ -1373,34 +1393,43 @@ int fs_mgr_remount_userdata_into_checkpointing(Fstab* fstab) {
		LINFO << "Checkpointing not needed. Don't remount";
		return 0;
		}
		if (entry->fs_mgr_flags.checkpoint_fs) {
		bool force_umount_for_f2fs =
		GetBoolProperty("sys.init.userdata_remount.force_umount_f2fs", false);
		if (fstab_entry->fs_mgr_flags.checkpoint_fs && !force_umount_for_f2fs) {
		// Userdata is f2fs, simply remount it.
		if (!checkpoint_manager.Update(&(*entry))) {
		if (!checkpoint_manager.Update(fstab_entry)) {
		LERROR << "Failed to remount userdata in checkpointing mode";
		return -1;
		}
		if (mount(entry->blk_device.c_str(), entry->mount_point.c_str(), "none",
		MS_REMOUNT \| entry->flags, entry->fs_options.c_str()) != 0) {
		if (mount(block_device.c_str(), fstab_entry->mount_point.c_str(), "none",
		MS_REMOUNT \| fstab_entry->flags, fstab_entry->fs_options.c_str()) != 0) {
		PERROR << "Failed to remount userdata in checkpointing mode";
		return -1;
		}
		} else {
		// STOPSHIP(b/143970043): support remounting for ext4 + metadata encryption.
		if (should_use_metadata_encryption(*entry)) {
		LWARNING << "Remounting into checkpointing is not supported for metadata encrypted "
		<< "ext4 userdata. Proceed with caution";
		return 0;
		}
		LINFO << "Unmounting /data before remounting into checkpointing mode";
		if (umount2("/data", UMOUNT_NOFOLLOW) != 0) {
		PERROR << "Failed to umount /data";
		return -1;
		}
		DeviceMapper& dm = DeviceMapper::Instance();
		// TODO(b/143970043): need to delete every dm-device under the one userdata is mounted on.
		if (!dm.DeleteDeviceIfExists("bow")) {
		LERROR << "Failed to delete dm-bow";
		while (dm.IsDmBlockDevice(block_device)) {
		auto next_device = dm.GetParentBlockDeviceByPath(block_device);
		auto name = dm.GetDmDeviceNameByPath(block_device);
		if (!name) {
		LERROR << "Failed to get dm-name for " << block_device;
		return -1;
		}
		LINFO << "Deleting " << block_device << " named " << *name;
		if (!dm.DeleteDevice(*name, 3s)) {
		return -1;
		}
		if (!next_device) {
		LERROR << "Failed to find parent device for " << block_device;
		}
		block_device = *next_device;
		}
		LINFO << "Remounting /data";
		// TODO(b/143970043): remove this hack after fs_mgr_mount_all is refactored.
		int result = fs_mgr_mount_all(fstab, MOUNT_MODE_ONLY_USERDATA);
		return result == FS_MGR_MNTALL_FAIL ? -1 : 0;