net: ethtool support to configure number of channels

Ethtool support to configure RX, TX and other channels. combined field
in struct ethtool_channels to reflect set of channel (RX, TX or other).
Other channel can be link interrupts, SR-IOV coordination etc.

ETHTOOL_GCHANNELS will report max and current number of RX channels,
max and current number of TX channels, max and current number of other channel
or max and current number of combined channel.

Number of channel can be modify upto max number of channel through
ETHTOOL_SCHANNELS command.

Ben Hutchings:
o define 'combined' and 'other' types.  Most multiqueue drivers pair up RX and TX
  queues so that most channels combine RX and TX work.
o Please could you use a kernel-doc comment to describe the structure.

Signed-off-by: Amit Kumar Salecha <amit.salecha@qlogic.com>
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 35 insertions, 0 deletions

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 43ef09fedd6e..41dee2de13ad 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -1446,6 +1446,35 @@ static int ethtool_set_ringparam(struct net_device *dev, void __user *useraddr)
         return dev->ethtool_ops->set_ringparam(dev, &ringparam);
 }
 
+static noinline_for_stack int ethtool_get_channels(struct net_device *dev,
+                                                   void __user *useraddr)
+{
+        struct ethtool_channels channels = { .cmd = ETHTOOL_GCHANNELS };
+
+        if (!dev->ethtool_ops->get_channels)
+                return -EOPNOTSUPP;
+
+        dev->ethtool_ops->get_channels(dev, &channels);
+
+        if (copy_to_user(useraddr, &channels, sizeof(channels)))
+                return -EFAULT;
+        return 0;
+}
+
+static noinline_for_stack int ethtool_set_channels(struct net_device *dev,
+                                                   void __user *useraddr)
+{
+        struct ethtool_channels channels;
+
+        if (!dev->ethtool_ops->set_channels)
+                return -EOPNOTSUPP;
+
+        if (copy_from_user(&channels, useraddr, sizeof(channels)))
+                return -EFAULT;
+
+        return dev->ethtool_ops->set_channels(dev, &channels);
+}
+
 static int ethtool_get_pauseparam(struct net_device *dev, void __user *useraddr)
 {
         struct ethtool_pauseparam pauseparam = { ETHTOOL_GPAUSEPARAM };
@@ -2007,6 +2036,12 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
         case ETHTOOL_SGRO:
                 rc = ethtool_set_one_feature(dev, useraddr, ethcmd);
                 break;
+        case ETHTOOL_GCHANNELS:
+                rc = ethtool_get_channels(dev, useraddr);
+                break;
+        case ETHTOOL_SCHANNELS:
+                rc = ethtool_set_channels(dev, useraddr);
+                break;
         default:
                 rc = -EOPNOTSUPP;
         }