net-next:v4: Add support to configure SR-IOV VF minimum and maximum Tx rate through ip tool.

o min_tx_rate puts lower limit on the VF bandwidth. VF is guaranteed
  to have a bandwidth of at least this value.
  max_tx_rate puts cap on the VF bandwidth. VF can have a bandwidth
  of up to this value.

o A new handler set_vf_rate for attr IFLA_VF_RATE has been introduced
  which takes 4 arguments:
  netdev, VF number, min_tx_rate, max_tx_rate

o ndo_set_vf_rate replaces ndo_set_vf_tx_rate handler.

o Drivers that currently implement ndo_set_vf_tx_rate should now call
  ndo_set_vf_rate instead and reject attempt to set a minimum bandwidth
  greater than 0 for IFLA_VF_TX_RATE when IFLA_VF_RATE is not yet
  implemented by driver.

o If user enters only one of either min_tx_rate or max_tx_rate, then,
  userland should read back the other value from driver and set both
  for IFLA_VF_RATE.
  Drivers that have not yet implemented IFLA_VF_RATE should always
  return min_tx_rate as 0 when read from ip tool.

o If both IFLA_VF_TX_RATE and IFLA_VF_RATE options are specified, then
  IFLA_VF_RATE should override.

o Idea is to have consistent display of rate values to user.

o Usage example: -

  ./ip link set p4p1 vf 0 rate 900

  ./ip link show p4p1
  32: p4p1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode
  DEFAULT qlen 1000
    link/ether 00:0e:1e:08:b0:f0 brd ff:ff:ff:ff:ff:ff
    vf 0 MAC 3e:a0:ca:bd:ae:5a, tx rate 900 (Mbps), max_tx_rate 900Mbps
    vf 1 MAC f6:c6:7c:3f:3d:6c
    vf 2 MAC 56:32:43:98:d7:71
    vf 3 MAC d6:be:c3:b5:85:ff
    vf 4 MAC ee:a9:9a:1e:19:14
    vf 5 MAC 4a:d0:4c:07:52:18
    vf 6 MAC 3a:76:44:93:62:f9
    vf 7 MAC 82:e9:e7:e3:15:1a

  ./ip link set p4p1 vf 0 max_tx_rate 300 min_tx_rate 200

  ./ip link show p4p1
  32: p4p1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode
  DEFAULT qlen 1000
    link/ether 00:0e:1e:08:b0:f0 brd ff:ff:ff:ff:ff:ff
    vf 0 MAC 3e:a0:ca:bd:ae:5a, tx rate 300 (Mbps), max_tx_rate 300Mbps,
    min_tx_rate 200Mbps
    vf 1 MAC f6:c6:7c:3f:3d:6c
    vf 2 MAC 56:32:43:98:d7:71
    vf 3 MAC d6:be:c3:b5:85:ff
    vf 4 MAC ee:a9:9a:1e:19:14
    vf 5 MAC 4a:d0:4c:07:52:18
    vf 6 MAC 3a:76:44:93:62:f9
    vf 7 MAC 82:e9:e7:e3:15:1a

  ./ip link set p4p1 vf 0 max_tx_rate 600 rate 300

  ./ip link show p4p1
  32: p4p1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode
  DEFAULT qlen 1000
    link/ether 00:0e:1e:08:b0:f brd ff:ff:ff:ff:ff:ff
    vf 0 MAC 3e:a0:ca:bd:ae:5, tx rate 600 (Mbps), max_tx_rate 600Mbps,
    min_tx_rate 200Mbps
    vf 1 MAC f6:c6:7c:3f:3d:6c
    vf 2 MAC 56:32:43:98:d7:71
    vf 3 MAC d6:be:c3:b5:85:ff
    vf 4 MAC ee:a9:9a:1e:19:14
    vf 5 MAC 4a:d0:4c:07:52:18
    vf 6 MAC 3a:76:44:93:62:f9
    vf 7 MAC 82:e9:e7:e3:15:1a

Signed-off-by: Sucheta Chakraborty <sucheta.chakraborty@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 8 deletions

diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index dcc5e5c69743..4693d004a223 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -1302,7 +1302,8 @@ static int be_get_vf_config(struct net_device *netdev, int vf,
 		return -EINVAL;
 
 	vi->vf = vf;
-	vi->tx_rate = vf_cfg->tx_rate;
+	vi->max_tx_rate = vf_cfg->tx_rate;
+	vi->min_tx_rate = 0;
 	vi->vlan = vf_cfg->vlan_tag & VLAN_VID_MASK;
 	vi->qos = vf_cfg->vlan_tag >> VLAN_PRIO_SHIFT;
 	memcpy(&vi->mac, vf_cfg->mac_addr, ETH_ALEN);
@@ -1342,7 +1343,8 @@ static int be_set_vf_vlan(struct net_device *netdev, int vf, u16 vlan, u8 qos)
 	return status;
 }
 
-static int be_set_vf_tx_rate(struct net_device *netdev, int vf, int rate)
+static int be_set_vf_tx_rate(struct net_device *netdev, int vf,
+			     int min_tx_rate, int max_tx_rate)
 {
 	struct be_adapter *adapter = netdev_priv(netdev);
 	int status = 0;
@@ -1353,18 +1355,21 @@ static int be_set_vf_tx_rate(struct net_device *netdev, int vf, int rate)
 	if (vf >= adapter->num_vfs)
 		return -EINVAL;
 
-	if (rate < 100 || rate > 10000) {
+	if (min_tx_rate)
+		return -EINVAL;
+
+	if (max_tx_rate < 100 || max_tx_rate > 10000) {
 		dev_err(&adapter->pdev->dev,
-			"tx rate must be between 100 and 10000 Mbps\n");
+			"max tx rate must be between 100 and 10000 Mbps\n");
 		return -EINVAL;
 	}
 
-	status = be_cmd_config_qos(adapter, rate / 10, vf + 1);
+	status = be_cmd_config_qos(adapter, max_tx_rate / 10, vf + 1);
 	if (status)
 		dev_err(&adapter->pdev->dev,
-			"tx rate %d on VF %d failed\n", rate, vf);
+			"max tx rate %d on VF %d failed\n", max_tx_rate, vf);
 	else
-		adapter->vf_cfg[vf].tx_rate = rate;
+		adapter->vf_cfg[vf].tx_rate = max_tx_rate;
 	return status;
 }
 static int be_set_vf_link_state(struct net_device *netdev, int vf,
@@ -4257,7 +4262,7 @@ static const struct net_device_ops be_netdev_ops = {
 	.ndo_vlan_rx_kill_vid	= be_vlan_rem_vid,
 	.ndo_set_vf_mac		= be_set_vf_mac,
 	.ndo_set_vf_vlan	= be_set_vf_vlan,
-	.ndo_set_vf_tx_rate	= be_set_vf_tx_rate,
+	.ndo_set_vf_rate	= be_set_vf_tx_rate,
 	.ndo_get_vf_config	= be_get_vf_config,
 	.ndo_set_vf_link_state  = be_set_vf_link_state,
 #ifdef CONFIG_NET_POLL_CONTROLLER