[ofa-general] [PATCH 4/10 REV5] [ethtool] Add ethtool support

[Krishna Kumar]

Add ethtool support to enable/disable batching.

Signed-off-by: Krishna Kumar <krkumar2 at in.ibm.com>
---
 include/linux/ethtool.h   |    2 ++
 include/linux/netdevice.h |    2 ++
 net/core/dev.c            |   44 ++++++++++++++++++++++++++++++++++++++++++++
 net/core/ethtool.c        |   27 +++++++++++++++++++++++++++
 4 files changed, 75 insertions(+)

diff -ruNp org/include/linux/ethtool.h new/include/linux/ethtool.h
--- org/include/linux/ethtool.h	2007-09-13 09:11:09.000000000 +0530
+++ new/include/linux/ethtool.h	2007-09-14 10:25:36.000000000 +0530
@@ -440,6 +440,8 @@ struct ethtool_ops {
 #define ETHTOOL_SFLAGS		0x00000026 /* Set flags bitmap(ethtool_value) */
 #define ETHTOOL_GPFLAGS		0x00000027 /* Get driver-private flags bitmap */
 #define ETHTOOL_SPFLAGS		0x00000028 /* Set driver-private flags bitmap */
+#define ETHTOOL_GBATCH		0x00000029 /* Get Batching (ethtool_value) */
+#define ETHTOOL_SBATCH		0x00000030 /* Set Batching (ethtool_value) */
 
 /* compatibility with older code */
 #define SPARC_ETH_GSET		ETHTOOL_GSET
diff -ruNp org/include/linux/netdevice.h new/include/linux/netdevice.h
--- org/include/linux/netdevice.h	2007-09-13 09:11:09.000000000 +0530
+++ new/include/linux/netdevice.h	2007-09-14 10:26:21.000000000 +0530
@@ -1331,6 +1331,8 @@ extern void		dev_set_promiscuity(struct 
 extern void		dev_set_allmulti(struct net_device *dev, int inc);
 extern void		netdev_state_change(struct net_device *dev);
 extern void		netdev_features_change(struct net_device *dev);
+extern int		dev_change_tx_batch_skb(struct net_device *dev,
+						unsigned long new_batch_skb);
 /* Load a device via the kmod */
 extern void		dev_load(struct net *net, const char *name);
 extern void		dev_mcast_init(void);
diff -ruNp org/net/core/dev.c new/net/core/dev.c
--- org/net/core/dev.c	2007-09-14 10:24:27.000000000 +0530
+++ new/net/core/dev.c	2007-09-14 10:25:36.000000000 +0530
@@ -963,6 +963,50 @@ void free_batching(struct net_dev
 	}
 }
 
+int dev_change_tx_batch_skb(struct net_device *dev, unsigned long new_batch_skb)
+{
+	int ret = 0;
+	struct sk_buff_head *blist = NULL;
+
+	if (!(dev->features & NETIF_F_BATCH_SKBS)) {
+		/* Driver doesn't support batching skb API */
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * Check if new value is same as the current (paranoia to use !! for
+	 * new_batch_skb as that will be boolean via ethtool).
+	 */
+	if (!!dev->skb_blist == !!new_batch_skb)
+		goto out;
+
+	if (new_batch_skb &&
+	    (blist = kmalloc(sizeof *blist, GFP_KERNEL)) == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/*
+	 * Block xmit as qdisc_restart() drops queue_lock before calling
+	 * driver xmit, and driver could find blist change under it.
+	 */
+	qdisc_block(dev);
+
+	spin_lock_bh(&dev->queue_lock);
+	if (new_batch_skb) {
+		skb_queue_head_init(blist);
+		dev->skb_blist = blist;
+	} else
+		free_batching(dev);
+	spin_unlock_bh(&dev->queue_lock);
+
+	qdisc_unblock(dev);
+
+out:
+	return ret;
+}
+
 /**
  *	dev_load 	- load a network module
  *	@name: name of interface
diff -ruNp org/net/core/ethtool.c new/net/core/ethtool.c
--- org/net/core/ethtool.c	2007-09-13 09:11:10.000000000 +0530
+++ new/net/core/ethtool.c	2007-09-14 10:25:36.000000000 +0530
@@ -556,6 +556,26 @@ static int ethtool_set_gso(struct net_de
 	return 0;
 }
 
+static int ethtool_get_batch(struct net_device *dev, char __user *useraddr)
+{
+	struct ethtool_value edata = { ETHTOOL_GBATCH };
+
+	edata.data = dev->skb_blist != NULL;
+	if (copy_to_user(useraddr, &edata, sizeof(edata)))
+		 return -EFAULT;
+	return 0;
+}
+
+static int ethtool_set_batch(struct net_device *dev, char __user *useraddr)
+{
+	struct ethtool_value edata;
+
+	if (copy_from_user(&edata, useraddr, sizeof(edata)))
+		return -EFAULT;
+
+	return dev_change_tx_batch_skb(dev, edata.data);
+}
+
 static int ethtool_self_test(struct net_device *dev, char __user *useraddr)
 {
 	struct ethtool_test test;
@@ -813,6 +833,7 @@ int dev_ethtool(struct net *net, struct 
 	case ETHTOOL_GGSO:
 	case ETHTOOL_GFLAGS:
 	case ETHTOOL_GPFLAGS:
+	case ETHTOOL_GBATCH:
 		break;
 	default:
 		if (!capable(CAP_NET_ADMIN))
@@ -956,6 +977,12 @@ int dev_ethtool(struct net *net, struct 
 		rc = ethtool_set_value(dev, useraddr,
 				       dev->ethtool_ops->set_priv_flags);
 		break;
+	case ETHTOOL_GBATCH:
+		rc = ethtool_get_batch(dev, useraddr);
+		break;
+	case ETHTOOL_SBATCH:
+		rc = ethtool_set_batch(dev, useraddr);
+		break;
 	default:
 		rc = -EOPNOTSUPP;
 	}