bnx2x: Add support for ethtool -L

Add support for ethtool -L/-l for setting and getting the number of RSS queues.
The 'combined' field is used as we don't support separate IRQ for Rx and Tx.

Signed-off-by: Merav Sicron <meravs@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c
index af84ebd..70c0881 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c
@@ -2796,6 +2796,84 @@
 	return bnx2x_config_rss_eth(bp, false);
 }
 
+/**
+ * bnx2x_get_channels - gets the number of RSS queues.
+ *
+ * @dev:		net device
+ * @channels:		returns the number of max / current queues
+ */
+static void bnx2x_get_channels(struct net_device *dev,
+			       struct ethtool_channels *channels)
+{
+	struct bnx2x *bp = netdev_priv(dev);
+
+	channels->max_combined = BNX2X_MAX_RSS_COUNT(bp);
+	channels->combined_count = BNX2X_NUM_ETH_QUEUES(bp);
+}
+
+/**
+ * bnx2x_change_num_queues - change the number of RSS queues.
+ *
+ * @bp:			bnx2x private structure
+ *
+ * Re-configure interrupt mode to get the new number of MSI-X
+ * vectors and re-add NAPI objects.
+ */
+static void bnx2x_change_num_queues(struct bnx2x *bp, int num_rss)
+{
+	bnx2x_del_all_napi(bp);
+	bnx2x_disable_msi(bp);
+	BNX2X_NUM_QUEUES(bp) = num_rss + NON_ETH_CONTEXT_USE;
+	bnx2x_set_int_mode(bp);
+	bnx2x_add_all_napi(bp);
+}
+
+/**
+ * bnx2x_set_channels - sets the number of RSS queues.
+ *
+ * @dev:		net device
+ * @channels:		includes the number of queues requested
+ */
+static int bnx2x_set_channels(struct net_device *dev,
+			      struct ethtool_channels *channels)
+{
+	struct bnx2x *bp = netdev_priv(dev);
+
+
+	DP(BNX2X_MSG_ETHTOOL,
+	   "set-channels command parameters: rx = %d, tx = %d, other = %d, combined = %d\n",
+	   channels->rx_count, channels->tx_count, channels->other_count,
+	   channels->combined_count);
+
+	/* We don't support separate rx / tx channels.
+	 * We don't allow setting 'other' channels.
+	 */
+	if (channels->rx_count || channels->tx_count || channels->other_count
+	    || (channels->combined_count == 0) ||
+	    (channels->combined_count > BNX2X_MAX_RSS_COUNT(bp))) {
+		DP(BNX2X_MSG_ETHTOOL, "command parameters not supported\n");
+		return -EINVAL;
+	}
+
+	/* Check if there was a change in the active parameters */
+	if (channels->combined_count == BNX2X_NUM_ETH_QUEUES(bp)) {
+		DP(BNX2X_MSG_ETHTOOL, "No change in active parameters\n");
+		return 0;
+	}
+
+	/* Set the requested number of queues in bp context.
+	 * Note that the actual number of queues created during load may be
+	 * less than requested if memory is low.
+	 */
+	if (unlikely(!netif_running(dev))) {
+		bnx2x_change_num_queues(bp, channels->combined_count);
+		return 0;
+	}
+	bnx2x_nic_unload(bp, UNLOAD_NORMAL);
+	bnx2x_change_num_queues(bp, channels->combined_count);
+	return bnx2x_nic_load(bp, LOAD_NORMAL);
+}
+
 static const struct ethtool_ops bnx2x_ethtool_ops = {
 	.get_settings		= bnx2x_get_settings,
 	.set_settings		= bnx2x_set_settings,
@@ -2827,6 +2905,8 @@
 	.get_rxfh_indir_size	= bnx2x_get_rxfh_indir_size,
 	.get_rxfh_indir		= bnx2x_get_rxfh_indir,
 	.set_rxfh_indir		= bnx2x_set_rxfh_indir,
+	.get_channels		= bnx2x_get_channels,
+	.set_channels		= bnx2x_set_channels,
 	.get_eee		= bnx2x_get_eee,
 	.set_eee		= bnx2x_set_eee,
 };