diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index 8424f5d0e5ed..8f0462d6855d 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -329,10 +329,32 @@ static ssize_t send_stream_version_show(struct kobject *kobj, } BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show); +static const char *rescue_opts[] = { + "usebackuproot", + "nologreplay", +}; + +static ssize_t supported_rescue_options_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + ssize_t ret = 0; + int i; + + for (i = 0; i < ARRAY_SIZE(rescue_opts); i++) + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s", + (i ? " " : ""), rescue_opts[i]); + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n"); + return ret; +} +BTRFS_ATTR(static_feature, supported_rescue_options, + supported_rescue_options_show); + static struct attribute *btrfs_supported_static_feature_attrs[] = { BTRFS_ATTR_PTR(static_feature, rmdir_subvol), BTRFS_ATTR_PTR(static_feature, supported_checksums), BTRFS_ATTR_PTR(static_feature, send_stream_version), + BTRFS_ATTR_PTR(static_feature, supported_rescue_options), NULL };