ldmvsw: Make sunvnet_common compatible with ldmvsw

  Modify sunvnet common code and data structures to be compatible
  with both sunvnet and ldmvsw drivers.

  Details:

  Sunvnet operates on "vnet-port" nodes which appear in the Machine
  Description (MD) in a guest domain. Ldmvsw operates on "vsw-port"
  nodes which appear in the MD of a service domain.

  A difference between the sunvnet driver and the ldmvsw driver is
  the sunvnet driver creates a network interface (i.e. a struct net_device)
  for every vnet-port *parent* "network" node. Several vnet-ports may appear
  under this common parent network node - each corresponding to a common parent
  network interface.  Conversely, since bridge/vswitch software will need
  to interface with every vsw-port in a system, the ldmvsw driver creates
  a network interface (i.e. a struct net_device) for every vsw-port - not
  every parent node as with sunvnet.  This difference required some special
  handling in the common code as explained below.

  There are 2 key data structures used by the sunvnet and ldmvsw drivers
  (which are now found in sunvnet_common.h):

  1. struct vnet_port
     This structure represents a vnet-port node in sunvnet and a vsw-port
     in the ldmvsw driver.

  2. struct vnet
     This structure represents a parent "network" node in sunvnet and a parent
     "virtual-network-switch" node in ldmvsw.

  Since the sunvnet driver allocates a net_device for every parent "network"
  node, a net_device member appears in the struct vnet. Since the ldmvsw
  driver allocates a net_device for every port, a net_device member was
  added to the vnet_port. The common code distinguishes which structure
  net_device member to use by checking a 'vsw' bit that was added to the
  vnet_port structure. See the VNET_PORT_TO_NET_DEVICE() marco in
  sunvnet_common.h.

  The netdev_priv() in sunvnet is allocated as a vnet. The netdev_priv()
  in ldmvsw is a vnet_port. Therefore, any place in the common code
  where a netdev_priv() call was made, a wrapper function was implemented
  in each driver to first get the vnet and/or vnet_port (in a driver
  specific way) and pass them as newly added parameters to the common
  functions (see wrapper funcs: vnet_set_rx_mode() and vnet_poll_controller()).
  Since these wrapper functions call __tx_port_find(), __tx_port_find() was
  moved from the common code back into sunvnet.c. Note - ldmvsw.c does not
  require this function.

  These changes also required that port_is_up() be made
  into a common function and thus it was given a _common suffix and
  exported like the other common functions.

  A wrapper function was also added for vnet_start_xmit_common() to pass a
  driver-specific function arg to return the port associated with a given
  struct sk_buff and struct net_device. This was required because
  vnet_start_xmit_common() grabs a lock prior to getting the associated
  port. Using a function pointer arg allowed the code to work unchanged
  without risking changes to the non-trivial locking logic in
  vnet_start_xmit_common().

  Signed-off-by: Aaron Young <aaron.young@oracle.com>
  Signed-off-by: Rashmi Narasimhan <rashmi.narasimhan@oracle.com>
  Reviewed-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
  Reviewed-by: Alexandre Chartre <Alexandre.Chartre@oracle.com>

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 70 insertions, 4 deletions

diff --git a/drivers/net/ethernet/sun/sunvnet.c b/drivers/net/ethernet/sun/sunvnet.c
index 5b9113524188..98c5f1612681 100644
--- a/drivers/net/ethernet/sun/sunvnet.c
+++ b/drivers/net/ethernet/sun/sunvnet.c
@@ -1,6 +1,7 @@
 /* sunvnet.c: Sun LDOM Virtual Network Driver.
  *
  * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
+ * Copyright (C) 2016 Oracle. All rights reserved.
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -84,18 +85,83 @@ static const struct ethtool_ops vnet_ethtool_ops = {
 static LIST_HEAD(vnet_list);
 static DEFINE_MUTEX(vnet_list_mutex);
 
+static struct vnet_port *__tx_port_find(struct vnet *vp, struct sk_buff *skb)
+{
+	unsigned int hash = vnet_hashfn(skb->data);
+	struct hlist_head *hp = &vp->port_hash[hash];
+	struct vnet_port *port;
+
+	hlist_for_each_entry_rcu(port, hp, hash) {
+		if (!sunvnet_port_is_up_common(port))
+			continue;
+		if (ether_addr_equal(port->raddr, skb->data))
+			return port;
+	}
+	list_for_each_entry_rcu(port, &vp->port_list, list) {
+		if (!port->switch_port)
+			continue;
+		if (!sunvnet_port_is_up_common(port))
+			continue;
+		return port;
+	}
+	return NULL;
+}
+
+/* func arg to vnet_start_xmit_common() to get the proper tx port */
+static struct vnet_port *vnet_tx_port_find(struct sk_buff *skb,
+					   struct net_device *dev)
+{
+	struct vnet *vp = netdev_priv(dev);
+
+	return __tx_port_find(vp, skb);
+}
+
+static u16 vnet_select_queue(struct net_device *dev, struct sk_buff *skb,
+			     void *accel_priv, select_queue_fallback_t fallback)
+{
+	struct vnet *vp = netdev_priv(dev);
+	struct vnet_port *port = __tx_port_find(vp, skb);
+
+	if (!port)
+		return 0;
+
+	return port->q_index;
+}
+
+/* Wrappers to common functions */
+static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	return sunvnet_start_xmit_common(skb, dev, vnet_tx_port_find);
+}
+
+static void vnet_set_rx_mode(struct net_device *dev)
+{
+	struct vnet *vp = netdev_priv(dev);
+
+	return sunvnet_set_rx_mode_common(dev, vp);
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void vnet_poll_controller(struct net_device *dev)
+{
+	struct vnet *vp = netdev_priv(dev);
+
+	return sunvnet_poll_controller_common(dev, vp);
+}
+#endif
+
 static const struct net_device_ops vnet_ops = {
 	.ndo_open		= sunvnet_open_common,
 	.ndo_stop		= sunvnet_close_common,
-	.ndo_set_rx_mode	= sunvnet_set_rx_mode_common,
+	.ndo_set_rx_mode	= vnet_set_rx_mode,
 	.ndo_set_mac_address	= sunvnet_set_mac_addr_common,
 	.ndo_validate_addr	= eth_validate_addr,
 	.ndo_tx_timeout		= sunvnet_tx_timeout_common,
 	.ndo_change_mtu		= sunvnet_change_mtu_common,
-	.ndo_start_xmit		= sunvnet_start_xmit_common,
-	.ndo_select_queue	= sunvnet_select_queue_common,
+	.ndo_start_xmit		= vnet_start_xmit,
+	.ndo_select_queue	= vnet_select_queue,
 #ifdef CONFIG_NET_POLL_CONTROLLER
-	.ndo_poll_controller	= sunvnet_poll_controller_common,
+	.ndo_poll_controller	= vnet_poll_controller,
 #endif
 };