Commit 32e62165 authored by Qu Wenruo's avatar Qu Wenruo Committed by David Sterba
Browse files

btrfs: introduce new "rescue=ignoresuperflags" mount option 



This new mount option allows the kernel to skip the super flags check,
it's mostly to allow the kernel to do a rescue mount of an interrupted
checksum conversion.

Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarQu Wenruo <wqu@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 169aaaf2

fs/btrfs/disk-io.c

+12 −4
Original line number Diff line number Diff line
@@ -2345,15 +2345,23 @@ int btrfs_validate_super(const struct btrfs_fs_info *fs_info, 
	u64 nodesize = btrfs_super_nodesize(sb);

	u64 sectorsize = btrfs_super_sectorsize(sb);

	int ret = 0;

	const bool ignore_flags = btrfs_test_opt(fs_info, IGNORESUPERFLAGS);



	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {

		btrfs_err(fs_info, "no valid FS found");

		ret = -EINVAL;

	}

	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {

		btrfs_err(fs_info, "unrecognized or unsupported super flag: 0x%llx",

	if ((btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP)) {

		if (!ignore_flags) {

			btrfs_err(fs_info,

			"unrecognized or unsupported super flag 0x%llx",

				  btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);

			ret = -EINVAL;

		} else {

			btrfs_info(fs_info,

			"unrecognized or unsupported super flags: 0x%llx, ignored",

				   btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);

		}

	}

	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {

		btrfs_err(fs_info, "tree_root level too big: %d >= %d",

fs/btrfs/fs.h

+1 −0
Original line number Diff line number Diff line
@@ -227,6 +227,7 @@ enum { 
	BTRFS_MOUNT_NODISCARD			= (1UL << 29),

	BTRFS_MOUNT_NOSPACECACHE		= (1UL << 30),

	BTRFS_MOUNT_IGNOREMETACSUMS		= (1UL << 31),

	BTRFS_MOUNT_IGNORESUPERFLAGS		= (1ULL << 32),

};



/*

fs/btrfs/super.c

+12 −1
Original line number Diff line number Diff line
@@ -177,6 +177,7 @@ enum { 
	Opt_rescue_ignorebadroots,

	Opt_rescue_ignoredatacsums,

	Opt_rescue_ignoremetacsums,

	Opt_rescue_ignoresuperflags,

	Opt_rescue_parameter_all,

};
@@ -187,8 +188,10 @@ static const struct constant_table btrfs_parameter_rescue[] = { 
	{ "ibadroots", Opt_rescue_ignorebadroots },

	{ "ignoredatacsums", Opt_rescue_ignoredatacsums },

	{ "ignoremetacsums", Opt_rescue_ignoremetacsums},

	{ "ignoresuperflags", Opt_rescue_ignoresuperflags},

	{ "idatacsums", Opt_rescue_ignoredatacsums },

	{ "imetacsums", Opt_rescue_ignoremetacsums},

	{ "isuperflags", Opt_rescue_ignoresuperflags},

	{ "all", Opt_rescue_parameter_all },

	{}

};
@@ -577,9 +580,13 @@ static int btrfs_parse_param(struct fs_context *fc, struct fs_parameter *param) 
		case Opt_rescue_ignoremetacsums:

			btrfs_set_opt(ctx->mount_opt, IGNOREMETACSUMS);

			break;

		case Opt_rescue_ignoresuperflags:

			btrfs_set_opt(ctx->mount_opt, IGNORESUPERFLAGS);

			break;

		case Opt_rescue_parameter_all:

			btrfs_set_opt(ctx->mount_opt, IGNOREDATACSUMS);

			btrfs_set_opt(ctx->mount_opt, IGNOREMETACSUMS);

			btrfs_set_opt(ctx->mount_opt, IGNORESUPERFLAGS);

			btrfs_set_opt(ctx->mount_opt, IGNOREBADROOTS);

			btrfs_set_opt(ctx->mount_opt, NOLOGREPLAY);

			break;
@@ -655,7 +662,8 @@ bool btrfs_check_options(const struct btrfs_fs_info *info, unsigned long *mount_ 
	    (check_ro_option(info, *mount_opt, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay") ||

	     check_ro_option(info, *mount_opt, BTRFS_MOUNT_IGNOREBADROOTS, "ignorebadroots") ||

	     check_ro_option(info, *mount_opt, BTRFS_MOUNT_IGNOREDATACSUMS, "ignoredatacsums") ||

	     check_ro_option(info, *mount_opt, BTRFS_MOUNT_IGNOREMETACSUMS, "ignoremetacsums")))

	     check_ro_option(info, *mount_opt, BTRFS_MOUNT_IGNOREMETACSUMS, "ignoremetacsums") ||

	     check_ro_option(info, *mount_opt, BTRFS_MOUNT_IGNORESUPERFLAGS, "ignoresuperflags")))

		ret = false;



	if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) &&
@@ -1073,6 +1081,8 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) 
		print_rescue_option(seq, "ignoredatacsums", &printed);

	if (btrfs_test_opt(info, IGNOREMETACSUMS))

		print_rescue_option(seq, "ignoremetacsums", &printed);

	if (btrfs_test_opt(info, IGNORESUPERFLAGS))

		print_rescue_option(seq, "ignoresuperflags", &printed);

	if (btrfs_test_opt(info, FLUSHONCOMMIT))

		seq_puts(seq, ",flushoncommit");

	if (btrfs_test_opt(info, DISCARD_SYNC))
@@ -1431,6 +1441,7 @@ static void btrfs_emit_options(struct btrfs_fs_info *info, 
	btrfs_info_if_set(info, old, IGNOREBADROOTS, "ignoring bad roots");

	btrfs_info_if_set(info, old, IGNOREDATACSUMS, "ignoring data csums");

	btrfs_info_if_set(info, old, IGNOREMETACSUMS, "ignoring meta csums");

	btrfs_info_if_set(info, old, IGNORESUPERFLAGS, "ignoring unknown super block flags");



	btrfs_info_if_unset(info, old, NODATACOW, "setting datacow");

	btrfs_info_if_unset(info, old, SSD, "not using ssd optimizations");

fs/btrfs/sysfs.c

+1 −0
Original line number Diff line number Diff line
@@ -386,6 +386,7 @@ static const char *rescue_opts[] = { 
	"ignorebadroots",

	"ignoredatacsums",

	"ignoremetacsums",

	"ignoresuperflags",

	"all",

};