[PATCH net 0/2] cxgb4 : DCBx fixes for apps/host lldp agents

[PATCH net 0/2] cxgb4 : DCBx fixes for apps/host lldp agents

[Anish Bhatt]

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.
-Anish

Anish Bhatt (2):
  cxgb4 : Improve handling of DCB negotiation or loss thereof
  cxgb4 : Handle dcb enable correctly

 drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c  | 55 +++++++++++++++++++++++--
 drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c |  6 ++-
 2 files changed, 56 insertions(+), 5 deletions(-)

-- 
2.1.2

[PATCH net 1/2] cxgb4 : Improve handling of DCB negotiation or loss thereof

[Anish Bhatt]

Clear out any DCB apps we might have added to kernel table when we lose DCB
sync (or IEEE equivalent event). These were previously left behind and not 
cleaned up correctly. IEEE allows individual components to work independently, 
 so improve check for IEEE completion by specifying individual components.

Fixes: 10b0046685ab ("cxgb4: IEEE fixes for DCBx state machine")

Signed-off-by: Anish Bhatt <anish@chelsio.com>
---
 drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c | 48 ++++++++++++++++++++++++--
 1 file changed, 45 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
index 8edf0f5..ee819fd 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
@@ -60,6 +60,42 @@ void cxgb4_dcb_version_init(struct net_device *dev)
 	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,
@@ -145,6 +181,7 @@ void cxgb4_dcb_state_fsm(struct net_device *dev,
 			 * 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;
@@ -833,11 +870,16 @@ static int cxgb4_setapp(struct net_device *dev, u8 app_idtype, u16 app_id,
 
 /* 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 +892,7 @@ static int cxgb4_ieee_getapp(struct net_device *dev, struct dcb_app *app)
 {
 	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 +914,7 @@ static int cxgb4_ieee_setapp(struct net_device *dev, struct dcb_app *app)
 {
 	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;
-- 
2.1.2

[PATCH net 2/2] cxgb4 : Handle dcb enable correctly

[Anish Bhatt]

Disabling DCBx in firmware automatically enables DCBx for control via host
lldp agents. Wait for an explicit setstate call from an lldp agents to enable
 DCBx instead.

Fixes: 76bcb31efc06 ("cxgb4 : Add DCBx support codebase and dcbnl_ops")

Signed-off-by: Anish Bhatt <anish@chelsio.com>
---
 drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c  | 7 ++++++-
 drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c | 6 +++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
index ee819fd..6fe300e 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
@@ -116,7 +116,6 @@ void cxgb4_dcb_state_fsm(struct net_device *dev,
 			/* we're going to use Host DCB */
 			dcb->state = CXGB4_DCB_STATE_HOST;
 			dcb->supported = CXGB4_DCBX_HOST_SUPPORT;
-			dcb->enabled = 1;
 			break;
 		}
 
@@ -386,6 +385,12 @@ static u8 cxgb4_setstate(struct net_device *dev, u8 enabled)
 {
 	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))
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 @@ int cxgb4_dcb_enabled(const struct net_device *dev)
 #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
-- 
2.1.2

Re: [PATCH net 0/2] cxgb4 : DCBx fixes for apps/host lldp agents

[David Miller]

From: Anish Bhatt <anish@chelsio.com>
Date: Thu, 23 Oct 2014 14:37:29 -0700

> 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.
> -Anish

Series applied, thanks Anish.