Merge branch 'cxgb4-net'

Anish Bhatt says:

====================
cxgb4 : DCBx fixes for apps/host lldp agents

This patchset  contains some minor fixes for cxgb4 DCBx code. Chiefly, cxgb4
was not cleaning up any apps added to kernel app table when link was lost.
Disabling DCBx in firmware would automatically set DCBx state to host-managed
and enabled, we now wait for an explicit enable call from an lldp agent instead

First patch was originally sent to net-next, but considering it applies to
correcting behaviour of code already in net, I think it qualifies as a bug fix.
====================

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

drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
index 8edf0f5..6fe300e 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
@@ -60,6 +60,42 @@
 	dcb->dcb_version = FW_PORT_DCB_VER_AUTO;
 }
 
+static void cxgb4_dcb_cleanup_apps(struct net_device *dev)
+{
+	struct port_info *pi = netdev2pinfo(dev);
+	struct adapter *adap = pi->adapter;
+	struct port_dcb_info *dcb = &pi->dcb;
+	struct dcb_app app;
+	int i, err;
+
+	/* zero priority implies remove */
+	app.priority = 0;
+
+	for (i = 0; i < CXGB4_MAX_DCBX_APP_SUPPORTED; i++) {
+		/* Check if app list is exhausted */
+		if (!dcb->app_priority[i].protocolid)
+			break;
+
+		app.protocol = dcb->app_priority[i].protocolid;
+
+		if (dcb->dcb_version == FW_PORT_DCB_VER_IEEE) {
+			app.selector = dcb->app_priority[i].sel_field + 1;
+			err = dcb_ieee_setapp(dev, &app);
+		} else {
+			app.selector = !!(dcb->app_priority[i].sel_field);
+			err = dcb_setapp(dev, &app);
+		}
+
+		if (err) {
+			dev_err(adap->pdev_dev,
+				"Failed DCB Clear %s Application Priority: sel=%d, prot=%d, , err=%d\n",
+				dcb_ver_array[dcb->dcb_version], app.selector,
+				app.protocol, -err);
+			break;
+		}
+	}
+}
+
 /* Finite State machine for Data Center Bridging.
  */
 void cxgb4_dcb_state_fsm(struct net_device *dev,
@@ -80,7 +116,6 @@
 			/* we're going to use Host DCB */
 			dcb->state = CXGB4_DCB_STATE_HOST;
 			dcb->supported = CXGB4_DCBX_HOST_SUPPORT;
-			dcb->enabled = 1;
 			break;
 		}
 
@@ -145,6 +180,7 @@
 			 * state.  We need to reset back to a ground state
 			 * of incomplete.
 			 */
+			cxgb4_dcb_cleanup_apps(dev);
 			cxgb4_dcb_state_init(dev);
 			dcb->state = CXGB4_DCB_STATE_FW_INCOMPLETE;
 			dcb->supported = CXGB4_DCBX_FW_SUPPORT;
@@ -349,6 +385,12 @@
 {
 	struct port_info *pi = netdev2pinfo(dev);
 
+	/* If DCBx is host-managed, dcb is enabled by outside lldp agents */
+	if (pi->dcb.state == CXGB4_DCB_STATE_HOST) {
+		pi->dcb.enabled = enabled;
+		return 0;
+	}
+
 	/* Firmware doesn't provide any mechanism to control the DCB state.
 	 */
 	if (enabled != (pi->dcb.state == CXGB4_DCB_STATE_FW_ALLSYNCED))
@@ -833,11 +875,16 @@
 
 /* Return whether IEEE Data Center Bridging has been negotiated.
  */
-static inline int cxgb4_ieee_negotiation_complete(struct net_device *dev)
+static inline int
+cxgb4_ieee_negotiation_complete(struct net_device *dev,
+				enum cxgb4_dcb_fw_msgs dcb_subtype)
 {
 	struct port_info *pi = netdev2pinfo(dev);
 	struct port_dcb_info *dcb = &pi->dcb;
 
+	if (dcb_subtype && !(dcb->msgs & dcb_subtype))
+		return 0;
+
 	return (dcb->state == CXGB4_DCB_STATE_FW_ALLSYNCED &&
 		(dcb->supported & DCB_CAP_DCBX_VER_IEEE));
 }
@@ -850,7 +897,7 @@
 {
 	int prio;
 
-	if (!cxgb4_ieee_negotiation_complete(dev))
+	if (!cxgb4_ieee_negotiation_complete(dev, CXGB4_DCB_FW_APP_ID))
 		return -EINVAL;
 	if (!(app->selector && app->protocol))
 		return -EINVAL;
@@ -872,7 +919,7 @@
 {
 	int ret;
 
-	if (!cxgb4_ieee_negotiation_complete(dev))
+	if (!cxgb4_ieee_negotiation_complete(dev, CXGB4_DCB_FW_APP_ID))
 		return -EINVAL;
 	if (!(app->selector && app->protocol))
 		return -EINVAL;

drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index 3f60070..97683c1 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -694,7 +694,11 @@
 #ifdef CONFIG_CHELSIO_T4_DCB
 	struct port_info *pi = netdev_priv(dev);
 
-	return pi->dcb.state == CXGB4_DCB_STATE_FW_ALLSYNCED;
+	if (!pi->dcb.enabled)
+		return 0;
+
+	return ((pi->dcb.state == CXGB4_DCB_STATE_FW_ALLSYNCED) ||
+		(pi->dcb.state == CXGB4_DCB_STATE_HOST));
 #else
 	return 0;
 #endif