MDB_PG_FLAGS_BLOCKED
(p->flags & MDB_PG_FLAGS_BLOCKED))
if (flags & MDB_PG_FLAGS_BLOCKED)
flags |= MDB_PG_FLAGS_BLOCKED;
p->flags |= MDB_PG_FLAGS_BLOCKED;
sg->flags &= ~MDB_PG_FLAGS_BLOCKED;
sg->flags |= MDB_PG_FLAGS_BLOCKED;