From: Sameeh Jubran <sameehj@amazon.com>
Date: Tue, 11 Jun 2019 14:58:09 +0300
Subject: [PATCH] net: ena: add ethtool function for changing io queue sizes
Origin: https://git.kernel.org/linus/eece4d2ab9d214e3b12f5ac1ed189a05793b28a5
Bug-Debian: https://bugs.debian.org/941291

Implement the set_ringparam() function of the ethtool interface
to enable the changing of io queue sizes.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_ethtool.c | 22 +++++++++++++++++++
 drivers/net/ethernet/amazon/ena/ena_netdev.c  | 14 ++++++++++++
 drivers/net/ethernet/amazon/ena/ena_netdev.h  |  5 ++++-
 3 files changed, 40 insertions(+), 1 deletion(-)

Index: linux/drivers/net/ethernet/amazon/ena/ena_ethtool.c
===================================================================
--- linux.orig/drivers/net/ethernet/amazon/ena/ena_ethtool.c
+++ linux/drivers/net/ethernet/amazon/ena/ena_ethtool.c
@@ -454,6 +454,27 @@ static void ena_get_ringparam(struct net
 	ring->rx_pending = adapter->rx_ring[0].ring_size;
 }
 
+static int ena_set_ringparam(struct net_device *netdev,
+			     struct ethtool_ringparam *ring)
+{
+	struct ena_adapter *adapter = netdev_priv(netdev);
+	u32 new_tx_size, new_rx_size;
+
+	new_tx_size = ring->tx_pending < ENA_MIN_RING_SIZE ?
+			ENA_MIN_RING_SIZE : ring->tx_pending;
+	new_tx_size = rounddown_pow_of_two(new_tx_size);
+
+	new_rx_size = ring->rx_pending < ENA_MIN_RING_SIZE ?
+			ENA_MIN_RING_SIZE : ring->rx_pending;
+	new_rx_size = rounddown_pow_of_two(new_rx_size);
+
+	if (new_tx_size == adapter->requested_tx_ring_size &&
+	    new_rx_size == adapter->requested_rx_ring_size)
+		return 0;
+
+	return ena_update_queue_sizes(adapter, new_tx_size, new_rx_size);
+}
+
 static u32 ena_flow_hash_to_flow_type(u16 hash_fields)
 {
 	u32 data = 0;
@@ -805,6 +826,7 @@ static const struct ethtool_ops ena_etht
 	.get_coalesce		= ena_get_coalesce,
 	.set_coalesce		= ena_set_coalesce,
 	.get_ringparam		= ena_get_ringparam,
+	.set_ringparam		= ena_set_ringparam,
 	.get_sset_count         = ena_get_sset_count,
 	.get_strings		= ena_get_strings,
 	.get_ethtool_stats      = ena_get_ethtool_stats,
Index: linux/drivers/net/ethernet/amazon/ena/ena_netdev.c
===================================================================
--- linux.orig/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ linux/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -2028,6 +2028,20 @@ static int ena_close(struct net_device *
 	return 0;
 }
 
+int ena_update_queue_sizes(struct ena_adapter *adapter,
+			   u32 new_tx_size,
+			   u32 new_rx_size)
+{
+	bool dev_up;
+
+	dev_up = test_bit(ENA_FLAG_DEV_UP, &adapter->flags);
+	ena_close(adapter->netdev);
+	adapter->requested_tx_ring_size = new_tx_size;
+	adapter->requested_rx_ring_size = new_rx_size;
+	ena_init_io_rings(adapter);
+	return dev_up ? ena_up(adapter) : 0;
+}
+
 static void ena_tx_csum(struct ena_com_tx_ctx *ena_tx_ctx, struct sk_buff *skb)
 {
 	u32 mss = skb_shinfo(skb)->gso_size;
Index: linux/drivers/net/ethernet/amazon/ena/ena_netdev.h
===================================================================
--- linux.orig/drivers/net/ethernet/amazon/ena/ena_netdev.h
+++ linux/drivers/net/ethernet/amazon/ena/ena_netdev.h
@@ -81,7 +81,6 @@
 #define ENA_DEFAULT_RING_SIZE	(1024)
 #define ENA_MIN_RING_SIZE	(256)
 
-
 #define ENA_TX_WAKEUP_THRESH		(MAX_SKB_FRAGS + 2)
 #define ENA_DEFAULT_RX_COPYBREAK	(256 - NET_IP_ALIGN)
 
@@ -386,6 +385,10 @@ void ena_dump_stats_to_dmesg(struct ena_
 
 void ena_dump_stats_to_buf(struct ena_adapter *adapter, u8 *buf);
 
+int ena_update_queue_sizes(struct ena_adapter *adapter,
+			   u32 new_tx_size,
+			   u32 new_rx_size);
+
 int ena_get_sset_count(struct net_device *netdev, int sset);
 
 #endif /* !(ENA_H) */
