ht_lock
mutex_init(&buf_hash_table.ht_locks[i].ht_lock,
kmutex_t ht_lock;
struct ht_lock ht_locks[BUF_LOCKS];
#define BUF_HASH_LOCK(idx) (&(BUF_HASH_LOCK_NTRY(idx).ht_lock))
mutex_destroy(&buf_hash_table.ht_locks[i].ht_lock);