[PATCH net-next v6 9/9] netdevsim: add HDS feature

[Taehee Yoo <ap420073@gmail.com>]

HDS options(tcp-data-split, hds-thresh) have dendencies between other
features like XDP. Basic dependencies are checked in the core API.
netdevsim is very useful to check basic dependencies.

The default tcp-data-split mode is UNKNOWN but netdevsim driver
returns DISABLED when ethtool dumps tcp-data-split mode.
The default value of HDS threshold is 0 and the maximum value is 1024.

ethtool shows like this.

ethtool -g eni1np1
Ring parameters for eni1np1:
Pre-set maximums:
...
HDS thresh:             1024
Current hardware settings:
...
TCP data split:         off
HDS thresh:             0

ethtool -G eni1np1 tcp-data-split on hds-thresh 1024
ethtool -g eni1np1
Ring parameters for eni1np1:
Pre-set maximums:
...
HDS thresh:             1024
Current hardware settings:
...
TCP data split:         on
HDS thresh:             1024

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
---

v6:
 - Patch added.

 drivers/net/netdevsim/ethtool.c   | 15 ++++++++++++++-
 drivers/net/netdevsim/netdevsim.h |  4 ++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/net/netdevsim/ethtool.c b/drivers/net/netdevsim/ethtool.c
index 5fe1eaef99b5..aa176f52fc3f 100644
--- a/drivers/net/netdevsim/ethtool.c
+++ b/drivers/net/netdevsim/ethtool.c
@@ -2,7 +2,6 @@
 // Copyright (c) 2020 Facebook
 
 #include <linux/debugfs.h>
-#include <linux/ethtool.h>
 #include <linux/random.h>
 
 #include "netdevsim.h"
@@ -72,6 +71,11 @@ static void nsim_get_ringparam(struct net_device *dev,
 	struct netdevsim *ns = netdev_priv(dev);
 
 	memcpy(ring, &ns->ethtool.ring, sizeof(ns->ethtool.ring));
+	memcpy(kernel_ring, &ns->ethtool.kernel_ring,
+	       sizeof(ns->ethtool.kernel_ring));
+
+	if (kernel_ring->tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_UNKNOWN)
+		kernel_ring->tcp_data_split = ETHTOOL_TCP_DATA_SPLIT_DISABLED;
 }
 
 static int nsim_set_ringparam(struct net_device *dev,
@@ -85,6 +89,9 @@ static int nsim_set_ringparam(struct net_device *dev,
 	ns->ethtool.ring.rx_jumbo_pending = ring->rx_jumbo_pending;
 	ns->ethtool.ring.rx_mini_pending = ring->rx_mini_pending;
 	ns->ethtool.ring.tx_pending = ring->tx_pending;
+	ns->ethtool.kernel_ring.tcp_data_split = kernel_ring->tcp_data_split;
+	ns->ethtool.kernel_ring.hds_thresh = kernel_ring->hds_thresh;
+
 	return 0;
 }
 
@@ -161,6 +168,8 @@ static int nsim_get_ts_info(struct net_device *dev,
 
 static const struct ethtool_ops nsim_ethtool_ops = {
 	.supported_coalesce_params	= ETHTOOL_COALESCE_ALL_PARAMS,
+	.supported_ring_params		= ETHTOOL_RING_USE_TCP_DATA_SPLIT |
+					  ETHTOOL_RING_USE_HDS_THRS,
 	.get_pause_stats	        = nsim_get_pause_stats,
 	.get_pauseparam		        = nsim_get_pauseparam,
 	.set_pauseparam		        = nsim_set_pauseparam,
@@ -182,6 +191,10 @@ static void nsim_ethtool_ring_init(struct netdevsim *ns)
 	ns->ethtool.ring.rx_jumbo_max_pending = 4096;
 	ns->ethtool.ring.rx_mini_max_pending = 4096;
 	ns->ethtool.ring.tx_max_pending = 4096;
+
+	ns->ethtool.kernel_ring.tcp_data_split = ETHTOOL_TCP_DATA_SPLIT_UNKNOWN;
+	ns->ethtool.kernel_ring.hds_thresh = 0;
+	ns->ethtool.kernel_ring.hds_thresh_max = NSIM_HDS_THRESHOLD_MAX;
 }
 
 void nsim_ethtool_init(struct netdevsim *ns)
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index bf02efa10956..6abbc627308d 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -16,6 +16,7 @@
 #include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/ethtool.h>
+#include <linux/ethtool_netlink.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/netdevice.h>
@@ -36,6 +37,8 @@
 #define NSIM_IPSEC_VALID		BIT(31)
 #define NSIM_UDP_TUNNEL_N_PORTS		4
 
+#define NSIM_HDS_THRESHOLD_MAX		1024
+
 struct nsim_sa {
 	struct xfrm_state *xs;
 	__be32 ipaddr[4];
@@ -87,6 +90,7 @@ struct nsim_ethtool {
 	struct nsim_ethtool_pauseparam pauseparam;
 	struct ethtool_coalesce coalesce;
 	struct ethtool_ringparam ring;
+	struct kernel_ethtool_ringparam kernel_ring;
 	struct ethtool_fecparam fec;
 };
 
-- 
2.34.1