via-velocity: add velocity_set_rxbufsize helper

It removes a dependancy from velocity_init_rd_ring to dev->mtu.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/via-velocity.c b/drivers/net/via-velocity.c
index 086d69c..370ce30 100644
--- a/drivers/net/via-velocity.c
+++ b/drivers/net/via-velocity.c
@@ -1207,6 +1207,11 @@
 	return done;
 }
 
+static void velocity_set_rxbufsize(struct velocity_info *vptr, int mtu)
+{
+	vptr->rx_buf_sz = (mtu <= ETH_DATA_LEN) ? PKT_BUF_SZ : mtu + 32;
+}
+
 /**
  *	velocity_init_rd_ring	-	set up receive ring
  *	@vptr: velocity to configure
@@ -1217,11 +1222,8 @@
 
 static int velocity_init_rd_ring(struct velocity_info *vptr)
 {
-	int mtu = vptr->dev->mtu;
 	int ret = -ENOMEM;
 
-	vptr->rx_buf_sz = (mtu <= ETH_DATA_LEN) ? PKT_BUF_SZ : mtu + 32;
-
 	vptr->rd_info = kcalloc(vptr->options.numrx,
 				sizeof(struct velocity_rd_info), GFP_KERNEL);
 	if (!vptr->rd_info)
@@ -1860,6 +1862,8 @@
 	struct velocity_info *vptr = netdev_priv(dev);
 	int ret;
 
+	velocity_set_rxbufsize(vptr, dev->mtu);
+
 	ret = velocity_init_rings(vptr);
 	if (ret < 0)
 		goto out;
@@ -1941,6 +1945,8 @@
 
 		dev->mtu = new_mtu;
 
+		velocity_set_rxbufsize(vptr, new_mtu);
+
 		ret = velocity_init_rd_ring(vptr);
 		if (ret < 0)
 			goto out_unlock;