ice: Handle LAN overflow event for VF queues

Currently we are not handling LAN overflow events. There can be cases
where LAN overflow events occur on VF queues, especially with Link Flow
Control (LFC) enabled on the controlling PF. In order to recover from
the LAN overflow event caused by a VF we need to determine if the queue
belongs to a VF and reset that VF accordingly.

The struct ice_aqc_event_lan_overflow returns a copy of the GLDCB_RTCTQ
register, which tells us what the queue index is in the global/device
space. The global queue index needs to first be converted to a PF space
queue index and then it can be used to find if a VF owns it.

Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 66 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c b/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
index 3666647da096..53a9e09c8f21 100644
--- a/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
@@ -1514,6 +1514,72 @@ static void ice_vc_reset_vf(struct ice_vf *vf)
 }
 
 /**
+ * ice_get_vf_from_pfq - get the VF who owns the PF space queue passed in
+ * @pf: PF used to index all VFs
+ * @pfq: queue index relative to the PF's function space
+ *
+ * If no VF is found who owns the pfq then return NULL, otherwise return a
+ * pointer to the VF who owns the pfq
+ */
+static struct ice_vf *ice_get_vf_from_pfq(struct ice_pf *pf, u16 pfq)
+{
+	int vf_id;
+
+	ice_for_each_vf(pf, vf_id) {
+		struct ice_vf *vf = &pf->vf[vf_id];
+		struct ice_vsi *vsi;
+		u16 rxq_idx;
+
+		vsi = pf->vsi[vf->lan_vsi_idx];
+
+		ice_for_each_rxq(vsi, rxq_idx)
+			if (vsi->rxq_map[rxq_idx] == pfq)
+				return vf;
+	}
+
+	return NULL;
+}
+
+/**
+ * ice_globalq_to_pfq - convert from global queue index to PF space queue index
+ * @pf: PF used for conversion
+ * @globalq: global queue index used to convert to PF space queue index
+ */
+static u32 ice_globalq_to_pfq(struct ice_pf *pf, u32 globalq)
+{
+	return globalq - pf->hw.func_caps.common_cap.rxq_first_id;
+}
+
+/**
+ * ice_vf_lan_overflow_event - handle LAN overflow event for a VF
+ * @pf: PF that the LAN overflow event happened on
+ * @event: structure holding the event information for the LAN overflow event
+ *
+ * Determine if the LAN overflow event was caused by a VF queue. If it was not
+ * caused by a VF, do nothing. If a VF caused this LAN overflow event trigger a
+ * reset on the offending VF.
+ */
+void
+ice_vf_lan_overflow_event(struct ice_pf *pf, struct ice_rq_event_info *event)
+{
+	u32 gldcb_rtctq, queue;
+	struct ice_vf *vf;
+
+	gldcb_rtctq = le32_to_cpu(event->desc.params.lan_overflow.prtdcb_ruptq);
+	dev_dbg(ice_pf_to_dev(pf), "GLDCB_RTCTQ: 0x%08x\n", gldcb_rtctq);
+
+	/* event returns device global Rx queue number */
+	queue = (gldcb_rtctq & GLDCB_RTCTQ_RXQNUM_M) >>
+		GLDCB_RTCTQ_RXQNUM_S;
+
+	vf = ice_get_vf_from_pfq(pf, ice_globalq_to_pfq(pf, queue));
+	if (!vf)
+		return;
+
+	ice_vc_reset_vf(vf);
+}
+
+/**
  * ice_vc_send_msg_to_vf - Send message to VF
  * @vf: pointer to the VF info
  * @v_opcode: virtual channel opcode