From: Javen Xu <javen_xu@realsil.com.cn>

This patch add support for changing rx queues by ethtool. We can set rx
1, 2, 4, 8 by ethtool -L eth1 rx num.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
changes in v2:
 - try to alloc memory for rx ring first. If failed, just roll back.
   Remove rtl_open and rtl8169_close. 
---
 drivers/net/ethernet/realtek/r8169_main.c | 133 ++++++++++++++++++++++
 1 file changed, 133 insertions(+)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index ea91cedc3100..7375d9e2e476 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -6375,6 +6375,137 @@ static void r8169_init_napi(struct rtl8169_private *tp)
 	}
 }
 
+static void rtl8169_get_channels(struct net_device *dev,
+				 struct ethtool_channels *ch)
+{
+	struct rtl8169_private *tp = netdev_priv(dev);
+
+	ch->max_rx = tp->hw_supp_num_rx_queues;
+	ch->max_tx = 1;
+	ch->max_other = 0;
+	ch->max_combined = 0;
+
+	ch->rx_count = tp->num_rx_rings;
+	ch->tx_count = 1;
+	ch->other_count = 0;
+	ch->combined_count = 0;
+}
+
+static int rtl8169_realloc_rx(struct rtl8169_private *tp,
+			      struct rtl8169_rx_ring *new_rx,
+			      int new_count)
+{
+	int i, ret;
+
+	new_rx[0].rdsar_reg = RxDescAddrLow;
+	for (i = 1; i < new_count; i++)
+		new_rx[i].rdsar_reg = (u16)(RDSAR_Q1_LOW + (i - 1) * 8);
+
+	for (i = 0; i < new_count; i++)
+		new_rx[i].num_rx_desc = NUM_RX_DESC;
+
+	for (i = 0; i < new_count; i++) {
+		struct rtl8169_rx_ring *ring = &new_rx[i];
+
+		ring->rx_desc_alloc_size = (NUM_RX_DESC + 1) * sizeof(struct RxDesc);
+		ring->rx_desc_array = dma_alloc_coherent(&tp->pci_dev->dev,
+							 ring->rx_desc_alloc_size,
+							 &ring->rx_phy_addr,
+							 GFP_KERNEL);
+		if (!ring->rx_desc_array) {
+			ret = -ENOMEM;
+			goto err_free;
+		}
+
+		memset(ring->rx_databuff, 0, sizeof(ring->rx_databuff));
+		ret = rtl8169_rx_fill(tp, ring);
+		if (ret) {
+			dma_free_coherent(&tp->pci_dev->dev, ring->rx_desc_alloc_size,
+					  ring->rx_desc_array, ring->rx_phy_addr);
+			goto err_free;
+		}
+	}
+	return 0;
+
+err_free:
+	while (--i >= 0) {
+		rtl8169_rx_clear(tp, &new_rx[i]);
+		dma_free_coherent(&tp->pci_dev->dev, new_rx[i].rx_desc_alloc_size,
+				  new_rx[i].rx_desc_array, new_rx[i].rx_phy_addr);
+	}
+	return ret;
+}
+
+static int rtl8169_set_channels(struct net_device *dev,
+				struct ethtool_channels *ch)
+{
+	struct rtl8169_private *tp = netdev_priv(dev);
+	bool if_running = netif_running(dev);
+	struct rtl8169_rx_ring *new_rx;
+	u8 old_tx_desc_type = tp->init_rx_desc_type;
+	u8 new_desc_type;
+	bool new_rss_enable;
+	int i, ret;
+
+	if (!tp->rss_support && (ch->rx_count > 1 || ch->tx_count > 1)) {
+		netdev_warn(dev, "This chip does not support multiple channels/RSS.\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (!(tp->features & RTL_VEC_MAP_ENABLE))
+		return -EINVAL;
+
+	new_rss_enable = (ch->rx_count > 1 && tp->rss_support);
+	new_desc_type = new_rss_enable ? RX_DESC_RING_TYPE_RSS : RX_DESC_RING_TYPE_DEFAULT;
+	tp->init_rx_desc_type = new_desc_type;
+
+	if (!if_running) {
+		tp->num_rx_rings = ch->rx_count;
+		tp->rss_enable = new_rss_enable;
+		return 0;
+	}
+
+	new_rx = kcalloc(R8169_MAX_RX_QUEUES, sizeof(*new_rx), GFP_KERNEL);
+	if (!new_rx)
+		return -ENOMEM;
+
+	ret = rtl8169_realloc_rx(tp, new_rx, ch->rx_count);
+	if (ret) {
+		kfree(new_rx);
+		tp->init_rx_desc_type = old_tx_desc_type;
+		return ret;
+	}
+
+	netif_stop_queue(dev);
+	rtl8169_down(tp);
+
+	for (i = 0; i < tp->num_rx_rings; i++)
+		rtl8169_rx_clear(tp, &tp->rx_ring[i]);
+	rtl8169_free_rx_desc(tp);
+
+	tp->num_rx_rings = ch->rx_count;
+	tp->rss_enable = new_rss_enable;
+
+	memset(tp->rx_ring, 0, sizeof(tp->rx_ring));
+	memcpy(tp->rx_ring, new_rx, sizeof(*new_rx) * ch->rx_count);
+
+	for (i = 0; i < tp->hw_supp_indir_tbl_entries; i++) {
+		if (tp->rss_enable)
+			tp->rss_indir_tbl[i] = ethtool_rxfh_indir_default(i, tp->num_rx_rings);
+		else
+			tp->rss_indir_tbl[i] = 0;
+	}
+
+	rtl_set_irq_mask(tp);
+
+	rtl8169_up(tp);
+	netif_start_queue(dev);
+
+	kfree(new_rx);
+
+	return 0;
+}
+
 static const struct ethtool_ops rtl8169_ethtool_ops = {
 	.supported_coalesce_params = ETHTOOL_COALESCE_USECS |
 				     ETHTOOL_COALESCE_MAX_FRAMES,
@@ -6393,6 +6524,8 @@ static const struct ethtool_ops rtl8169_ethtool_ops = {
 	.nway_reset		= phy_ethtool_nway_reset,
 	.get_eee		= rtl8169_get_eee,
 	.set_eee		= rtl8169_set_eee,
+	.get_channels		= rtl8169_get_channels,
+	.set_channels		= rtl8169_set_channels,
 	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
 	.set_link_ksettings	= rtl8169_set_link_ksettings,
 	.get_ringparam		= rtl8169_get_ringparam,
-- 
2.43.0