[S390] cio: move cdev pointer to io_subchannel_private

Move the subchannels ccw device pointer from drv_data to
the private data for I/O subchannels, since it is not the
only drv_data for I/O subchannels. The next step will be
to make io_subchannel_private the new drv_data for I/O
subchannels.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/io_sch.h

@@ -10,6 +10,7 @@
 struct io_subchannel_private {
 	union orb orb;		/* operation request block */
 	struct ccw1 sense_ccw;	/* static ccw for sense command */
+	struct ccw_device *cdev;/* pointer to the child ccw device */
 	struct {
 		unsigned int suspend:1;	/* allow suspend */
 		unsigned int prefetch:1;/* deny prefetch */
@@ -18,8 +19,20 @@ struct io_subchannel_private {
 } __aligned(8);
 
 #define to_io_private(n) ((struct io_subchannel_private *)n->private)
-#define sch_get_cdev(n) (dev_get_drvdata(&n->dev))
-#define sch_set_cdev(n, c) (dev_set_drvdata(&n->dev, c))
+
+static inline struct ccw_device *sch_get_cdev(struct subchannel *sch)
+{
+	struct io_subchannel_private *priv = to_io_private(sch);
+	return priv ? priv->cdev : NULL;
+}
+
+static inline void sch_set_cdev(struct subchannel *sch,
+				struct ccw_device *cdev)
+{
+	struct io_subchannel_private *priv = to_io_private(sch);
+	if (priv)
+		priv->cdev = cdev;
+}
 
 #define MAX_CIWS 8