iavf: Enable support for up to 16 queues

Previous devices could only allocate 4 MSI-X vectors per VF so there was a
limitation of 4 queues. 800-series hardware can allocate more than 4 MSI-X
vectors, so expand the limitation on the number of queues that the driver
can support to account for these capabilities.

Fix ethtool channel operations to accommodate this change and adjust the
reporting of max number of queues to what is given to us by the PF. Since
we're not requesting queues above this value, just trigger reset to
activate the queues, which we already own.

Finally, fix a test condition that would display an incorrect error
message.

Signed-off-by: Mitch Williams <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>
Tested-by: Andrew Bowers <[email protected]>
Signed-off-by: Jeff Kirsher <[email protected]>

Author: mawilli1

drivers/net/ethernet/intel/iavf/iavf.h

@@ -81,7 +81,7 @@ struct iavf_vsi {
 #define IAVF_TX_DESC(R, i) (&(((struct iavf_tx_desc *)((R)->desc))[i]))
 #define IAVF_TX_CTXTDESC(R, i) \
 	(&(((struct iavf_tx_context_desc *)((R)->desc))[i]))
-#define IAVF_MAX_REQ_QUEUES 4
+#define IAVF_MAX_REQ_QUEUES 16
 
 #define IAVF_HKEY_ARRAY_SIZE ((IAVF_VFQF_HKEY_MAX_INDEX + 1) * 4)
 #define IAVF_HLUT_ARRAY_SIZE ((IAVF_VFQF_HLUT_MAX_INDEX + 1) * 4)

drivers/net/ethernet/intel/iavf/iavf_ethtool.c

@@ -860,7 +860,7 @@ static void iavf_get_channels(struct net_device *netdev,
 	struct iavf_adapter *adapter = netdev_priv(netdev);
 
 	/* Report maximum channels */
-	ch->max_combined = IAVF_MAX_REQ_QUEUES;
+	ch->max_combined = adapter->vsi_res->num_queue_pairs;
 
 	ch->max_other = NONQ_VECS;
 	ch->other_count = NONQ_VECS;
@@ -881,14 +881,7 @@ static int iavf_set_channels(struct net_device *netdev,
 			     struct ethtool_channels *ch)
 {
 	struct iavf_adapter *adapter = netdev_priv(netdev);
-	int num_req = ch->combined_count;
-
-	if (num_req != adapter->num_active_queues &&
-	    !(adapter->vf_res->vf_cap_flags &
-	      VIRTCHNL_VF_OFFLOAD_REQ_QUEUES)) {
-		dev_info(&adapter->pdev->dev, "PF is not capable of queue negotiation.\n");
-		return -EINVAL;
-	}
+	u32 num_req = ch->combined_count;
 
 	if ((adapter->vf_res->vf_cap_flags & VIRTCHNL_VF_OFFLOAD_ADQ) &&
 	    adapter->num_tc) {
@@ -899,14 +892,19 @@ static int iavf_set_channels(struct net_device *netdev,
 	/* All of these should have already been checked by ethtool before this
 	 * even gets to us, but just to be sure.
 	 */
-	if (num_req <= 0 || num_req > IAVF_MAX_REQ_QUEUES)
+	if (num_req > adapter->vsi_res->num_queue_pairs)
 		return -EINVAL;
 
+	if (num_req == adapter->num_active_queues)
+		return 0;
+
 	if (ch->rx_count || ch->tx_count || ch->other_count != NONQ_VECS)
 		return -EINVAL;
 
 	adapter->num_req_queues = num_req;
-	return iavf_request_queues(adapter, num_req);
+	adapter->flags |= IAVF_FLAG_REINIT_ITR_NEEDED;
+	iavf_schedule_reset(adapter);
+	return 0;
 }
 
 /**

drivers/net/ethernet/intel/iavf/iavf_main.c

@@ -3450,7 +3450,7 @@ int iavf_process_config(struct iavf_adapter *adapter)
 	}
 
 	if (num_req_queues &&
-	    num_req_queues != adapter->vsi_res->num_queue_pairs) {
+	    num_req_queues > adapter->vsi_res->num_queue_pairs) {
 		/* Problem.  The PF gave us fewer queues than what we had
 		 * negotiated in our request.  Need a reset to see if we can't
 		 * get back to a working state.

drivers/net/ethernet/intel/iavf/iavf_virtchnl.c

@@ -396,33 +396,6 @@ void iavf_map_queues(struct iavf_adapter *adapter)
 	kfree(vimi);
 }
 
-/**
- * iavf_request_queues
- * @adapter: adapter structure
- * @num: number of requested queues
- *
- * We get a default number of queues from the PF.  This enables us to request a
- * different number.  Returns 0 on success, negative on failure
- **/
-int iavf_request_queues(struct iavf_adapter *adapter, int num)
-{
-	struct virtchnl_vf_res_request vfres;
-
-	if (adapter->current_op != VIRTCHNL_OP_UNKNOWN) {
-		/* bail because we already have a command pending */
-		dev_err(&adapter->pdev->dev, "Cannot request queues, command %d pending\n",
-			adapter->current_op);
-		return -EBUSY;
-	}
-
-	vfres.num_queue_pairs = min_t(int, num, num_online_cpus());
-
-	adapter->current_op = VIRTCHNL_OP_REQUEST_QUEUES;
-	adapter->flags |= IAVF_FLAG_REINIT_ITR_NEEDED;
-	return iavf_send_pf_msg(adapter, VIRTCHNL_OP_REQUEST_QUEUES,
-				(u8 *)&vfres, sizeof(vfres));
-}
-
 /**
  * iavf_add_ether_addrs
  * @adapter: adapter structure