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>
diff --git a/include/linux/if_link.h b/include/linux/if_link.h
index a86784d..119130e 100644
--- a/include/linux/if_link.h
+++ b/include/linux/if_link.h
@@ -10,8 +10,9 @@
 	__u8 mac[32];
 	__u32 vlan;
 	__u32 qos;
-	__u32 tx_rate;
 	__u32 spoofchk;
 	__u32 linkstate;
+	__u32 min_tx_rate;
+	__u32 max_tx_rate;
 };
 #endif /* _LINUX_IF_LINK_H */
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index f4ad247..9ec3a94 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -850,7 +850,8 @@
  *	SR-IOV management functions.
  * int (*ndo_set_vf_mac)(struct net_device *dev, int vf, u8* mac);
  * int (*ndo_set_vf_vlan)(struct net_device *dev, int vf, u16 vlan, u8 qos);
- * int (*ndo_set_vf_tx_rate)(struct net_device *dev, int vf, int rate);
+ * int (*ndo_set_vf_rate)(struct net_device *dev, int vf, int min_tx_rate,
+ *			  int max_tx_rate);
  * int (*ndo_set_vf_spoofchk)(struct net_device *dev, int vf, bool setting);
  * int (*ndo_get_vf_config)(struct net_device *dev,
  *			    int vf, struct ifla_vf_info *ivf);
@@ -1044,8 +1045,9 @@
 						  int queue, u8 *mac);
 	int			(*ndo_set_vf_vlan)(struct net_device *dev,
 						   int queue, u16 vlan, u8 qos);
-	int			(*ndo_set_vf_tx_rate)(struct net_device *dev,
-						      int vf, int rate);
+	int			(*ndo_set_vf_rate)(struct net_device *dev,
+						   int vf, int min_tx_rate,
+						   int max_tx_rate);
 	int			(*ndo_set_vf_spoofchk)(struct net_device *dev,
 						       int vf, bool setting);
 	int			(*ndo_get_vf_config)(struct net_device *dev,
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 9a7f7ac..622e7910 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -399,9 +399,10 @@
 	IFLA_VF_UNSPEC,
 	IFLA_VF_MAC,		/* Hardware queue specific attributes */
 	IFLA_VF_VLAN,
-	IFLA_VF_TX_RATE,	/* TX Bandwidth Allocation */
+	IFLA_VF_TX_RATE,	/* Max TX Bandwidth Allocation */
 	IFLA_VF_SPOOFCHK,	/* Spoof Checking on/off switch */
 	IFLA_VF_LINK_STATE,	/* link state enable/disable/auto switch */
+	IFLA_VF_RATE,		/* Min and Max TX Bandwidth Allocation */
 	__IFLA_VF_MAX,
 };
 
@@ -423,6 +424,12 @@
 	__u32 rate; /* Max TX bandwidth in Mbps, 0 disables throttling */
 };
 
+struct ifla_vf_rate {
+	__u32 vf;
+	__u32 min_tx_rate; /* Min Bandwidth in Mbps */
+	__u32 max_tx_rate; /* Max Bandwidth in Mbps */
+};
+
 struct ifla_vf_spoofchk {
 	__u32 vf;
 	__u32 setting;