--- 2.3.49/drivers/block/nbd.c.~1~	Mon Feb 21 15:17:31 2000
+++ 2.3.49/drivers/block/nbd.c	Sat Mar  4 16:55:00 2000
@@ -24,6 +24,7 @@
  *          structure with userland
  */
 
+#undef	NBD_PLUGGABLE
 #define PARANOIA
 #include <linux/major.h>
 
@@ -62,10 +63,11 @@
 static int requests_out;
 #endif
 
+static void nbd_plug_device(request_queue_t *q, kdev_t dev) { }
+
 static int nbd_open(struct inode *inode, struct file *file)
 {
 	int dev;
-	struct nbd_device *nbdev;
 
 	if (!inode)
 		return -EINVAL;
@@ -73,12 +75,7 @@
 	if (dev >= MAX_NBD)
 		return -ENODEV;
 
-	nbdev = &nbd_dev[dev];
 	nbd_dev[dev].refcnt++;
-	if (!(nbdev->flags & NBD_INITIALISED)) {
-		init_MUTEX(&nbdev->queue_lock);
-		nbdev->flags |= NBD_INITIALISED;
-	}
 	MOD_INC_USE_COUNT;
 	return 0;
 }
@@ -215,6 +212,7 @@
 void nbd_do_it(struct nbd_device *lo)
 {
 	struct request *req;
+	int dequeued;
 
 	down (&lo->queue_lock);
 	while (!list_empty(&lo->queue_head)) {
@@ -237,9 +235,11 @@
 		list_del(&req->queue);
 		up (&lo->queue_lock);
 		
-		nbd_end_request(req);
+		dequeued = nbd_end_request(req);
 
 		down (&lo->queue_lock);
+		if (!dequeued)
+			list_add(&req->queue, &lo->queue_head);
 	}
  out:
 	up (&lo->queue_lock);
@@ -248,6 +248,7 @@
 void nbd_clear_que(struct nbd_device *lo)
 {
 	struct request *req;
+	int dequeued;
 
 	while (!list_empty(&lo->queue_head)) {
 		req = blkdev_entry_prev_request(&lo->queue_head);
@@ -265,9 +266,11 @@
 		list_del(&req->queue);
 		up(&lo->queue_lock);
 
-		nbd_end_request(req);
+		dequeued = nbd_end_request(req);
 
 		down(&lo->queue_lock);
+		if (!dequeued)
+			list_add(&req->queue, &lo->queue_head);
 	}
 }
 
@@ -469,12 +472,17 @@
 	blksize_size[MAJOR_NR] = nbd_blksizes;
 	blk_size[MAJOR_NR] = nbd_sizes;
 	blk_init_queue(BLK_DEFAULT_QUEUE(MAJOR_NR), do_nbd_request);
+#ifndef NBD_PLUGGABLE
+	blk_queue_pluggable(BLK_DEFAULT_QUEUE(MAJOR_NR), nbd_plug_device);
+#endif
 	blk_queue_headactive(BLK_DEFAULT_QUEUE(MAJOR_NR), 0);
 	for (i = 0; i < MAX_NBD; i++) {
 		nbd_dev[i].refcnt = 0;
 		nbd_dev[i].file = NULL;
 		nbd_dev[i].magic = LO_MAGIC;
 		nbd_dev[i].flags = 0;
+		INIT_LIST_HEAD(&nbd_dev[i].queue_head);
+		init_MUTEX(&nbd_dev[i]->queue_lock);
 		nbd_blksizes[i] = 1024;
 		nbd_blksize_bits[i] = 10;
 		nbd_bytesizes[i] = 0x7ffffc00; /* 2GB */
--- 2.3.49/include/linux/nbd.h.~1~	Thu Feb 17 14:05:33 2000
+++ 2.3.49/include/linux/nbd.h	Sat Mar  4 16:43:55 2000
@@ -30,22 +30,35 @@
 extern int requests_out;
 #endif
 
-static void 
+static int 
 nbd_end_request(struct request *req)
 {
 	unsigned long flags;
+	int ret = 0;
 
 #ifdef PARANOIA
 	requests_out++;
 #endif
+	/*
+	 * This is a very dirty hack that we have to do to handle
+	 * merged requests because end_request stuff is a bit
+	 * broken. The fact we have to do this only if there
+	 * aren't errors looks even more silly.
+	 */
+	if (!req->errors) {
+		req->sector += req->current_nr_sectors;
+		req->nr_sectors -= req->current_nr_sectors;
+	}
+
 	spin_lock_irqsave(&io_request_lock, flags);
 	if (end_that_request_first( req, !req->errors, "nbd" ))
 		goto out;
+	ret = 1;
 	end_that_request_last( req );
 
 out:
 	spin_unlock_irqrestore(&io_request_lock, flags);
-	return;
+	return ret;
 }
 
 #define MAX_NBD 128
@@ -56,7 +69,6 @@
 	int harderror;		/* Code of hard error			*/
 #define NBD_READ_ONLY 0x0001
 #define NBD_WRITE_NOCHK 0x0002
-#define NBD_INITIALISED 0x0004
 	struct socket * sock;
 	struct file * file; 		/* If == NULL, device is not ready, yet	*/
 	int magic;			/* FIXME: not if debugging is off	*/