req->errors = 0;
                spin_unlock_irq(q->queue_lock);
 
-               down(&lo->tx_lock);
+               mutex_lock(&lo->tx_lock);
                if (unlikely(!lo->sock)) {
-                       up(&lo->tx_lock);
+                       mutex_unlock(&lo->tx_lock);
                        printk(KERN_ERR "%s: Attempted send on closed socket\n",
                               lo->disk->disk_name);
                        req->errors++;
                }
 
                lo->active_req = NULL;
-               up(&lo->tx_lock);
+               mutex_unlock(&lo->tx_lock);
                wake_up_all(&lo->active_wq);
 
                spin_lock_irq(q->queue_lock);
  
        case NBD_CLEAR_SOCK:
                error = 0;
-               down(&lo->tx_lock);
+               mutex_lock(&lo->tx_lock);
                lo->sock = NULL;
-               up(&lo->tx_lock);
+               mutex_unlock(&lo->tx_lock);
                file = lo->file;
                lo->file = NULL;
                nbd_clear_que(lo);
                 * FIXME: This code is duplicated from sys_shutdown, but
                 * there should be a more generic interface rather than
                 * calling socket ops directly here */
-               down(&lo->tx_lock);
+               mutex_lock(&lo->tx_lock);
                if (lo->sock) {
                        printk(KERN_WARNING "%s: shutting down socket\n",
                                lo->disk->disk_name);
                                SEND_SHUTDOWN|RCV_SHUTDOWN);
                        lo->sock = NULL;
                }
-               up(&lo->tx_lock);
+               mutex_unlock(&lo->tx_lock);
                file = lo->file;
                lo->file = NULL;
                nbd_clear_que(lo);
                nbd_dev[i].flags = 0;
                spin_lock_init(&nbd_dev[i].queue_lock);
                INIT_LIST_HEAD(&nbd_dev[i].queue_head);
-               init_MUTEX(&nbd_dev[i].tx_lock);
+               mutex_init(&nbd_dev[i].tx_lock);
                init_waitqueue_head(&nbd_dev[i].active_wq);
                nbd_dev[i].blksize = 1024;
                nbd_dev[i].bytesize = 0x7ffffc00ULL << 10; /* 2TB */
 
 #ifdef __KERNEL__
 
 #include <linux/wait.h>
+#include <linux/mutex.h>
 
 /* values for flags field */
 #define NBD_READ_ONLY 0x0001
        struct request *active_req;
        wait_queue_head_t active_wq;
 
-       struct semaphore tx_lock;
+       struct mutex tx_lock;
        struct gendisk *disk;
        int blksize;
        u64 bytesize;