From 86f669b2b7491b5697d9e63538c960ad7e94c6cc Mon Sep 17 00:00:00 2001
From: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Date: Mon, 19 Feb 2018 13:30:39 -0600
Subject: [PATCH] ibmvnic: Make napi usage dynamic

References: bsc#1081498
Patch-mainline: v4.17-rc1
Git-commit: 86f669b2b7491b5697d9e63538c960ad7e94c6cc

In order to handle the number of rx sub crqs changing during a driver
reset, the ibmvnic driver also needs to update the number of napi.
To do this the code to init and free napi's is moved to their own
routines so they can be called during the reset process.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 70 ++++++++++++++++++++++++--------------
 1 file changed, 45 insertions(+), 25 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 33cfd277f008..7dc67de269f5 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -730,6 +730,43 @@ static void ibmvnic_napi_disable(struct ibmvnic_adapter *adapter)
 	adapter->napi_enabled = false;
 }
 
+static int init_napi(struct ibmvnic_adapter *adapter)
+{
+	int i;
+
+	adapter->napi = kcalloc(adapter->req_rx_queues,
+				sizeof(struct napi_struct), GFP_KERNEL);
+	if (!adapter->napi)
+		return -ENOMEM;
+
+	for (i = 0; i < adapter->req_rx_queues; i++) {
+		netdev_dbg(adapter->netdev, "Adding napi[%d]\n", i);
+		netif_napi_add(adapter->netdev, &adapter->napi[i],
+			       ibmvnic_poll, NAPI_POLL_WEIGHT);
+	}
+
+	return 0;
+}
+
+static void release_napi(struct ibmvnic_adapter *adapter)
+{
+	int i;
+
+	if (!adapter->napi)
+		return;
+
+	for (i = 0; i < adapter->num_active_rx_scrqs; i++) {
+		if (&adapter->napi[i]) {
+			netdev_dbg(adapter->netdev,
+				   "Releasing napi[%d]\n", i);
+			netif_napi_del(&adapter->napi[i]);
+		}
+	}
+
+	kfree(adapter->napi);
+	adapter->napi = NULL;
+}
+
 static int ibmvnic_login(struct net_device *netdev)
 {
 	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
@@ -795,8 +832,6 @@ static void release_login_rsp_buffer(struct ibmvnic_adapter *adapter)
 
 static void release_resources(struct ibmvnic_adapter *adapter)
 {
-	int i;
-
 	release_vpd_data(adapter);
 
 	release_tx_pools(adapter);
@@ -805,19 +840,7 @@ static void release_resources(struct ibmvnic_adapter *adapter)
 	release_stats_token(adapter);
 	release_stats_buffers(adapter);
 	release_error_buffers(adapter);
-
-	if (adapter->napi) {
-		for (i = 0; i < adapter->req_rx_queues; i++) {
-			if (&adapter->napi[i]) {
-				netdev_dbg(adapter->netdev,
-					   "Releasing napi[%d]\n", i);
-				netif_napi_del(&adapter->napi[i]);
-			}
-		}
-	}
-	kfree(adapter->napi);
-	adapter->napi = NULL;
-
+	release_napi(adapter);
 	release_login_rsp_buffer(adapter);
 }
 
@@ -937,7 +960,7 @@ static int ibmvnic_get_vpd(struct ibmvnic_adapter *adapter)
 static int init_resources(struct ibmvnic_adapter *adapter)
 {
 	struct net_device *netdev = adapter->netdev;
-	int i, rc;
+	int rc;
 
 	rc = set_real_num_queues(netdev);
 	if (rc)
@@ -963,16 +986,10 @@ static int init_resources(struct ibmvnic_adapter *adapter)
 	}
 
 	adapter->map_id = 1;
-	adapter->napi = kcalloc(adapter->req_rx_queues,
-				sizeof(struct napi_struct), GFP_KERNEL);
-	if (!adapter->napi)
-		return -ENOMEM;
 
-	for (i = 0; i < adapter->req_rx_queues; i++) {
-		netdev_dbg(netdev, "Adding napi[%d]\n", i);
-		netif_napi_add(netdev, &adapter->napi[i], ibmvnic_poll,
-			       NAPI_POLL_WEIGHT);
-	}
+	rc = init_napi(adapter);
+	if (rc)
+		return rc;
 
 	send_map_query(adapter);
 
@@ -1687,6 +1704,9 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 			init_rx_pools(netdev);
 			init_tx_pools(netdev);
 
+			release_napi(adapter);
+			init_napi(adapter);
+
 			adapter->num_active_tx_scrqs = adapter->req_tx_queues;
 			adapter->num_active_rx_scrqs = adapter->req_rx_queues;
 		} else {
-- 
2.13.6