nd_btt_arena_is_valid
if (!nd_btt_arena_is_valid(btt->nd_btt, super)) {
bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super);
EXPORT_SYMBOL(nd_btt_arena_is_valid);
if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
if (!nd_btt_arena_is_valid(nd_btt, btt_sb))