[PATCH net-next v1] hinic: add set_channels ethtool_ops support

[PATCH net-next v1] hinic: add set_channels ethtool_ops support

[Luo bin]

add support to change TX/RX queue number with ethtool -L

Signed-off-by: Luo bin <luobin9@huawei.com>
---
 .../net/ethernet/huawei/hinic/hinic_ethtool.c | 46 +++++++++++++++----
 .../net/ethernet/huawei/hinic/hinic_main.c    |  2 +-
 drivers/net/ethernet/huawei/hinic/hinic_tx.c  |  5 ++
 3 files changed, 44 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/huawei/hinic/hinic_ethtool.c b/drivers/net/ethernet/huawei/hinic/hinic_ethtool.c
index ace18d258049..9796c1fbe132 100644
--- a/drivers/net/ethernet/huawei/hinic/hinic_ethtool.c
+++ b/drivers/net/ethernet/huawei/hinic/hinic_ethtool.c
@@ -619,14 +619,43 @@ static void hinic_get_channels(struct net_device *netdev,
 	struct hinic_dev *nic_dev = netdev_priv(netdev);
 	struct hinic_hwdev *hwdev = nic_dev->hwdev;
 
-	channels->max_rx = hwdev->nic_cap.max_qps;
-	channels->max_tx = hwdev->nic_cap.max_qps;
-	channels->max_other = 0;
-	channels->max_combined = 0;
-	channels->rx_count = hinic_hwdev_num_qps(hwdev);
-	channels->tx_count = hinic_hwdev_num_qps(hwdev);
-	channels->other_count = 0;
-	channels->combined_count = 0;
+	channels->max_combined = nic_dev->max_qps;
+	channels->combined_count = hinic_hwdev_num_qps(hwdev);
+}
+
+static int hinic_set_channels(struct net_device *netdev,
+			      struct ethtool_channels *channels)
+{
+	struct hinic_dev *nic_dev = netdev_priv(netdev);
+	unsigned int count = channels->combined_count;
+	int err;
+
+	if (!count) {
+		netif_err(nic_dev, drv, netdev,
+			  "Unsupported combined_count: 0\n");
+		return -EINVAL;
+	}
+
+	netif_info(nic_dev, drv, netdev, "Set max combined queue number from %d to %d\n",
+		   hinic_hwdev_num_qps(nic_dev->hwdev), count);
+
+	if (netif_running(netdev)) {
+		netif_info(nic_dev, drv, netdev, "Restarting netdev\n");
+		hinic_close(netdev);
+
+		nic_dev->hwdev->nic_cap.num_qps = count;
+
+		err = hinic_open(netdev);
+		if (err) {
+			netif_err(nic_dev, drv, netdev,
+				  "Failed to open netdev\n");
+			return -EFAULT;
+		}
+	} else {
+		nic_dev->hwdev->nic_cap.num_qps = count;
+	}
+
+	return 0;
 }
 
 static int hinic_get_rss_hash_opts(struct hinic_dev *nic_dev,
@@ -1219,6 +1248,7 @@ static const struct ethtool_ops hinic_ethtool_ops = {
 	.get_ringparam = hinic_get_ringparam,
 	.set_ringparam = hinic_set_ringparam,
 	.get_channels = hinic_get_channels,
+	.set_channels = hinic_set_channels,
 	.get_rxnfc = hinic_get_rxnfc,
 	.set_rxnfc = hinic_set_rxnfc,
 	.get_rxfh_key_size = hinic_get_rxfh_key_size,
diff --git a/drivers/net/ethernet/huawei/hinic/hinic_main.c b/drivers/net/ethernet/huawei/hinic/hinic_main.c
index e3ff119fe341..2c07b03bf6e5 100644
--- a/drivers/net/ethernet/huawei/hinic/hinic_main.c
+++ b/drivers/net/ethernet/huawei/hinic/hinic_main.c
@@ -326,7 +326,6 @@ static void hinic_enable_rss(struct hinic_dev *nic_dev)
 	int i, node, err = 0;
 	u16 num_cpus = 0;
 
-	nic_dev->max_qps = hinic_hwdev_max_num_qps(hwdev);
 	if (nic_dev->max_qps <= 1) {
 		nic_dev->flags &= ~HINIC_RSS_ENABLE;
 		nic_dev->rss_limit = nic_dev->max_qps;
@@ -1043,6 +1042,7 @@ static int nic_dev_init(struct pci_dev *pdev)
 	nic_dev->rq_depth = HINIC_RQ_DEPTH;
 	nic_dev->sriov_info.hwdev = hwdev;
 	nic_dev->sriov_info.pdev = pdev;
+	nic_dev->max_qps = num_qps;
 
 	sema_init(&nic_dev->mgmt_lock, 1);
 
diff --git a/drivers/net/ethernet/huawei/hinic/hinic_tx.c b/drivers/net/ethernet/huawei/hinic/hinic_tx.c
index 4c66a0bc1b28..6da761d7a6ef 100644
--- a/drivers/net/ethernet/huawei/hinic/hinic_tx.c
+++ b/drivers/net/ethernet/huawei/hinic/hinic_tx.c
@@ -470,6 +470,11 @@ netdev_tx_t hinic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
 	struct hinic_txq *txq;
 	struct hinic_qp *qp;
 
+	if (unlikely(!netif_carrier_ok(netdev))) {
+		dev_kfree_skb_any(skb);
+		return NETDEV_TX_OK;
+	}
+
 	txq = &nic_dev->txqs[q_id];
 	qp = container_of(txq->sq, struct hinic_qp, sq);
 
-- 
2.17.1

Re: [PATCH net-next v1] hinic: add set_channels ethtool_ops support

[David Miller]

From: Luo bin <luobin9@huawei.com>
Date: Fri, 15 May 2020 19:42:12 +0000

> add support to change TX/RX queue number with ethtool -L
> 
> Signed-off-by: Luo bin <luobin9@huawei.com>

I don't think you are properly following the semantics of this
ethtool command with your changes.

In fact, you are breaking the hinic_get_channels() function which
is properly advertising the ->max_* values currently.  Now it will
return zero.

Whatever is advertised in ->max_* should be the driver's maximum
capabilities.

This means that the user can request anything in the range from '1'
to these max values.

Whatever the user asks for in ->combined_count and elsewhere, you
_MUST_ provide or return an error.

That is not what hinic_set_channels() is doing.  It is using
combined_count as a "limit" rather than the value to use.