[S390] qdio: Sanitize do_QDIO sanity checks

Remove unneeded sanity checks from do_QDIO since this is the hot path.
Change the type of bufnr and count to unsigned int so the check for the
maximum value works.

Reported-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/asm/qdio.h

@@ -380,7 +380,7 @@ extern int qdio_establish(struct qdio_initialize *);
 extern int qdio_activate(struct ccw_device *);
 
 extern int do_QDIO(struct ccw_device *cdev, unsigned int callflags,
-		   int q_nr, int bufnr, int count);
+		   int q_nr, unsigned int bufnr, unsigned int count);
 extern int qdio_cleanup(struct ccw_device*, int);
 extern int qdio_shutdown(struct ccw_device*, int);
 extern int qdio_free(struct ccw_device *);

drivers/s390/cio/qdio_main.c

@@ -1497,18 +1497,13 @@ out:
  * @count: how many buffers to process
  */
 int do_QDIO(struct ccw_device *cdev, unsigned int callflags,
-	    int q_nr, int bufnr, int count)
+	    int q_nr, unsigned int bufnr, unsigned int count)
 {
 	struct qdio_irq *irq_ptr;
 
-	if ((bufnr > QDIO_MAX_BUFFERS_PER_Q) ||
-	    (count > QDIO_MAX_BUFFERS_PER_Q) ||
-	    (q_nr >= QDIO_MAX_QUEUES_PER_IRQ))
+	if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
 		return -EINVAL;
 
-	if (!count)
-		return 0;
-
 	irq_ptr = cdev->private->qdio_data;
 	if (!irq_ptr)
 		return -ENODEV;