[PATCH net-next v16 0/7] r8169: add RSS support for RTL8127

[PATCH net-next v16 0/7] r8169: add RSS support for RTL8127

[javen]

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

This patch series adds RSS (Receive Side Scaling) support for the r8169
ethernet driver, specifically for RTL8127 (RTL_GIGA_MAC_VER_80).

RSS enables packet distribution across multiple receive queues, which can
significantly improve network throughput on multi-core systems by allowing
parallel processing of incoming packets.

Key features:
- Multi-queue RX support (up to 8 queues)
- MSI-X interrupt with vector mapping
- Dynamic queue configuration via ethtool (-L)
- RSS hash computation for flow classification

Experiments:
Platform: AMD Ryzen Embedded R2514 with Radeon Graphics(4 Cores/8 Threads)
Arch: x86_64
Test command: 
  Server: iperf3 -s
  Client: iperf3 -c 192.168.2.1 -P 20 -t 3600
Monitor: mpstat -P ALL 1

Before this patch (Without RSS):
  Throughput: Unstable, fluctuating between 3.76 Gbits/sec and
  8.2 Gbits/sec.
  CPU Usage: A single CPU core is fully occupied with softirq reaching 
  up to 96%.

After this patch (With RSS enabled):
  Throughput: Stable at 9.42 Gbits/sec.
  CPU Usage: The traffic load is evenly distributed across multiple CPU
  cores. The maximum softirq on a single core dropped to 63%.
  
Other Experiments:
Link: https://lore.kernel.org/netdev/0A5279953D81BB9C+f50c9b49-3e5d-467f-b69a-7e49ed223383@radxa.com/

Javen Xu (7):
  r8169: prepare for multi irqs and napi
  r8169: refactor RX path to prepare for multi-queue
  r8169: add support for new interrupt mapping
  r8169: prepare for new interrupt mapping
  r8169: add support and enable rss
  r8169: move struct ethtool_ops
  r8169: add get_channel support for ethtool

 drivers/net/ethernet/realtek/r8169_main.c | 1122 ++++++++++++++++++---
 1 file changed, 973 insertions(+), 149 deletions(-)

-- 
2.43.0

[PATCH net-next v16 1/7] r8169: prepare for multi irqs and napi

[javen]

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

This patch converts the single struct napi_struct into a dynamically
allocated array indexed by IRQ. This is a preparation step for adding
RSS support. Currently, irq_nvecs and num_rx_rings are still hard-coded
to 1. Note that this patch adds netif_napi_set_irq() to expose NAPI-IRQ
mapping via netlink, and updates probe log format to show the total
number of IRQs.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
Changes in v2:
 - remove some unused definitions, such as index, name in rtl8169_irq
 - remove array imr and isr
 - remove min_irq_nvecs and max_irq_nvecs, replaced with help function
   get_min_irq_nvecs and get_max_irq_nvecs
 - alloc irq by flags, instead of PCI_IRQ_ALL_TYPES

Changes in v3:
 - add enum rtl_isr_version to replace macro definition
 - remove struct rtl8169_napi, use napi_struct array instead and alloc
   memory for this array dynamically
 - remove struct rtl8169_irq

Changes in v4:
 - change retval to ret in rtl8169_set_real_num_queue()
 - reverse xmas tree in rtl8169_poll() and rtl8169_interrupt()
 - remove tp->hw_supp_isr_ver

Changes in v5:
 - rtl8169_request_irq(), when failed, only free irqs which are
   allocated
 - remove rss_support, simplied napi init, call r8169_init_napi()
   directly
 - remove rtl_isr_version, INTR_VEC_MAP_MASK, INTR_VEC_MAP_STATUS,
   R8169_MAX_MSIX_VEC, rss_enable, recheck_desc_ownbit
 - rtl_software_parameter_initialize() this function will be expanded in
   next patch, so i want to remain it here.

Changes in v6:
 - Fix netpoll crash
 - Fix use-after-free during driver unload by registering a devm action
   for netif_napi_del()
 - remove tp->irq

Changes in v7:
 - pass NAPI as arg to rtl_rx()
 - use netif_set_real_num_queues to replace rtl8169_set_real_num_queues
 - replace rtl_software_parameter_initialize with rtl_setup_rx_params

Changes in v8:
 - no changes

Changes in v9:
 - no changes

Changes in v10:
 - no changes

Changes in v11:
 - no changes

Changes in v12:
 - no changes

Changes in v13:
 - Fix sleep-in-atomic bug in netpoll by passing 0 to
   rtl8169_interrupt()
 - call netif_napi_set_irq() to properly associate NAPI with IRQ vector
 - Fix print format for unsigned int tp->irq_nvecs from %d to %u

Changes in v14:
 - modify commit message and patch title
 - fall back to request_irq() + pci_irq_vector() instead of
   pci_request_irq() to avoid dropping IRQF_NO_THREAD flag for MSI/MSI-X
 - add phylink_destory() in NAPI kcalloc failure path

Changes in v15:
 - no changes

Changes in v16:
 - modify commit message
---
 drivers/net/ethernet/realtek/r8169_main.c | 165 ++++++++++++++++++----
 1 file changed, 136 insertions(+), 29 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 43c46d483eb8..3afb9a4b1aff 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -761,7 +761,6 @@ struct rtl8169_private {
 	struct pci_dev *pci_dev;
 	struct net_device *dev;
 	struct phy_device *phydev;
-	struct napi_struct napi;
 	enum mac_version mac_version;
 	enum rtl_dash_type dash_type;
 	enum rtl_sfp_mode sfp_mode;
@@ -774,10 +773,12 @@ struct rtl8169_private {
 	dma_addr_t RxPhyAddr;
 	struct page *Rx_databuff[NUM_RX_DESC];	/* Rx data buffers */
 	struct ring_info tx_skb[NUM_TX_DESC];	/* Tx data buffers */
+	struct napi_struct *rtl8169_napi;
+	unsigned int num_rx_rings;
 	u16 cp_cmd;
 	u16 tx_lpi_timer;
 	u32 irq_mask;
-	int irq;
+	unsigned int irq_nvecs;
 	struct clk *clk;
 	int speed;
 
@@ -2769,6 +2770,11 @@ static void rtl_hw_reset(struct rtl8169_private *tp)
 	rtl_loop_wait_low(tp, &rtl_chipcmd_cond, 100, 100);
 }
 
+static void rtl_setup_rx_params(struct rtl8169_private *tp)
+{
+	tp->num_rx_rings = 1;
+}
+
 static void rtl_request_firmware(struct rtl8169_private *tp)
 {
 	struct rtl_fw *rtl_fw;
@@ -4431,9 +4437,21 @@ static void rtl8169_tx_clear(struct rtl8169_private *tp)
 	netdev_reset_queue(tp->dev);
 }
 
+static void rtl8169_napi_disable(struct rtl8169_private *tp)
+{
+	for (int i = 0; i < tp->irq_nvecs; i++)
+		napi_disable(&tp->rtl8169_napi[i]);
+}
+
+static void rtl8169_napi_enable(struct rtl8169_private *tp)
+{
+	for (int i = 0; i < tp->irq_nvecs; i++)
+		napi_enable(&tp->rtl8169_napi[i]);
+}
+
 static void rtl8169_cleanup(struct rtl8169_private *tp)
 {
-	napi_disable(&tp->napi);
+	rtl8169_napi_disable(tp);
 
 	/* Give a racing hard_start_xmit a few cycles to complete. */
 	synchronize_net();
@@ -4479,7 +4497,7 @@ static void rtl_reset_work(struct rtl8169_private *tp)
 	for (i = 0; i < NUM_RX_DESC; i++)
 		rtl8169_mark_to_asic(tp->RxDescArray + i);
 
-	napi_enable(&tp->napi);
+	rtl8169_napi_enable(tp);
 	rtl_hw_start(tp);
 }
 
@@ -4933,7 +4951,8 @@ static inline void rtl8169_rx_csum(struct sk_buff *skb, u32 opts1)
 		skb_checksum_none_assert(skb);
 }
 
-static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp, int budget)
+static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
+		  int budget, struct napi_struct *napi)
 {
 	struct device *d = tp_to_dev(tp);
 	int count;
@@ -4985,7 +5004,7 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp, int budget
 			goto release_descriptor;
 		}
 
-		skb = napi_alloc_skb(&tp->napi, pkt_size);
+		skb = napi_alloc_skb(napi, pkt_size);
 		if (unlikely(!skb)) {
 			dev->stats.rx_dropped++;
 			goto release_descriptor;
@@ -5009,7 +5028,7 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp, int budget
 		if (skb->pkt_type == PACKET_MULTICAST)
 			dev->stats.multicast++;
 
-		napi_gro_receive(&tp->napi, skb);
+		napi_gro_receive(napi, skb);
 
 		dev_sw_netstats_rx_add(dev, pkt_size);
 release_descriptor:
@@ -5021,8 +5040,12 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp, int budget
 
 static irqreturn_t rtl8169_interrupt(int irq, void *dev_instance)
 {
-	struct rtl8169_private *tp = dev_instance;
-	u32 status = rtl_get_events(tp);
+	struct napi_struct *napi = dev_instance;
+	struct rtl8169_private *tp;
+	u32 status;
+
+	tp = netdev_priv(napi->dev);
+	status = rtl_get_events(tp);
 
 	if ((status & 0xffff) == 0xffff || !(status & tp->irq_mask))
 		return IRQ_NONE;
@@ -5043,13 +5066,55 @@ static irqreturn_t rtl8169_interrupt(int irq, void *dev_instance)
 	}
 
 	rtl_irq_disable(tp);
-	napi_schedule(&tp->napi);
+	napi_schedule(napi);
 out:
 	rtl_ack_events(tp, status);
 
 	return IRQ_HANDLED;
 }
 
+static void rtl8169_free_irq(struct rtl8169_private *tp)
+{
+	struct pci_dev *pdev = tp->pci_dev;
+	int i, irq;
+
+	for (i = 0; i < tp->irq_nvecs; i++) {
+		struct napi_struct *napi = &tp->rtl8169_napi[i];
+
+		irq = pci_irq_vector(pdev, i);
+		free_irq(irq, napi);
+	}
+}
+
+static int rtl8169_request_irq(struct rtl8169_private *tp)
+{
+	struct pci_dev *pdev = tp->pci_dev;
+	struct net_device *dev = tp->dev;
+	struct napi_struct *napi;
+	unsigned long irqflags;
+	int i, rc, irq;
+
+	irqflags = pci_dev_msi_enabled(pdev) ? IRQF_NO_THREAD : IRQF_SHARED;
+
+	for (i = 0; i < tp->irq_nvecs; i++) {
+		napi = &tp->rtl8169_napi[i];
+		irq = pci_irq_vector(pdev, i);
+
+		rc = request_irq(irq, rtl8169_interrupt, irqflags,
+				 dev->name, napi);
+		if (rc)
+			goto free_irq;
+	}
+	return 0;
+
+free_irq:
+	while (--i >= 0) {
+		irq = pci_irq_vector(pdev, i);
+		free_irq(irq, &tp->rtl8169_napi[i]);
+	}
+	return rc;
+}
+
 static void rtl_task(struct work_struct *work)
 {
 	struct rtl8169_private *tp =
@@ -5084,13 +5149,13 @@ static void rtl_task(struct work_struct *work)
 
 static int rtl8169_poll(struct napi_struct *napi, int budget)
 {
-	struct rtl8169_private *tp = container_of(napi, struct rtl8169_private, napi);
-	struct net_device *dev = tp->dev;
-	int work_done;
+	struct rtl8169_private *tp = netdev_priv(napi->dev);
+	struct net_device *dev = napi->dev;
+	int work_done = 0;
 
 	rtl_tx(dev, tp, budget);
 
-	work_done = rtl_rx(dev, tp, budget);
+	work_done = rtl_rx(dev, tp, budget, napi);
 
 	if (work_done < budget && napi_complete_done(napi, work_done))
 		rtl_irq_enable(tp);
@@ -5175,7 +5240,7 @@ static void rtl8169_up(struct rtl8169_private *tp)
 	if (tp->phydev)
 		rtl8169_init_phy(tp);
 
-	napi_enable(&tp->napi);
+	rtl8169_napi_enable(tp);
 	enable_work(&tp->wk.work);
 	rtl_reset_work(tp);
 }
@@ -5192,7 +5257,7 @@ static int rtl8169_close(struct net_device *dev)
 	rtl8169_down(tp);
 	rtl8169_rx_clear(tp);
 
-	free_irq(tp->irq, tp);
+	rtl8169_free_irq(tp);
 
 	phylink_disconnect_phy(tp->phylink);
 
@@ -5213,7 +5278,8 @@ static void rtl8169_netpoll(struct net_device *dev)
 {
 	struct rtl8169_private *tp = netdev_priv(dev);
 
-	rtl8169_interrupt(tp->irq, tp);
+	for (int i = 0; i < tp->irq_nvecs; i++)
+		rtl8169_interrupt(0, &tp->rtl8169_napi[i]);
 }
 #endif
 
@@ -5221,7 +5287,6 @@ static int rtl_open(struct net_device *dev)
 {
 	struct rtl8169_private *tp = netdev_priv(dev);
 	struct pci_dev *pdev = tp->pci_dev;
-	unsigned long irqflags;
 	int retval = -ENOMEM;
 
 	pm_runtime_get_sync(&pdev->dev);
@@ -5246,8 +5311,7 @@ static int rtl_open(struct net_device *dev)
 
 	rtl_request_firmware(tp);
 
-	irqflags = pci_dev_msi_enabled(pdev) ? IRQF_NO_THREAD : IRQF_SHARED;
-	retval = request_irq(tp->irq, rtl8169_interrupt, irqflags, dev->name, tp);
+	retval = rtl8169_request_irq(tp);
 	if (retval < 0)
 		goto err_release_fw_2;
 
@@ -5266,7 +5330,7 @@ static int rtl_open(struct net_device *dev)
 	return retval;
 
 err_free_irq:
-	free_irq(tp->irq, tp);
+	rtl8169_free_irq(tp);
 err_release_fw_2:
 	rtl_release_firmware(tp);
 	rtl8169_rx_clear(tp);
@@ -5419,6 +5483,14 @@ static void rtl_shutdown(struct pci_dev *pdev)
 		pci_prepare_to_sleep(pdev);
 }
 
+static void r8169_free_napi(struct rtl8169_private *tp)
+{
+	for (int i = 0; i < tp->irq_nvecs; i++)
+		netif_napi_del(&tp->rtl8169_napi[i]);
+
+	kfree(tp->rtl8169_napi);
+}
+
 static void rtl_remove_one(struct pci_dev *pdev)
 {
 	struct rtl8169_private *tp = pci_get_drvdata(pdev);
@@ -5432,6 +5504,7 @@ static void rtl_remove_one(struct pci_dev *pdev)
 		r8169_remove_leds(tp->leds);
 
 	unregister_netdev(tp->dev);
+	r8169_free_napi(tp);
 	phylink_destroy(tp->phylink);
 
 	if (tp->dash_type != RTL_DASH_NONE)
@@ -5473,7 +5546,9 @@ static void rtl_set_irq_mask(struct rtl8169_private *tp)
 
 static int rtl_alloc_irq(struct rtl8169_private *tp)
 {
+	struct pci_dev *pdev = tp->pci_dev;
 	unsigned int flags;
+	int nvecs;
 
 	switch (tp->mac_version) {
 	case RTL_GIGA_MAC_VER_02 ... RTL_GIGA_MAC_VER_06:
@@ -5489,7 +5564,14 @@ static int rtl_alloc_irq(struct rtl8169_private *tp)
 		break;
 	}
 
-	return pci_alloc_irq_vectors(tp->pci_dev, 1, 1, flags);
+	nvecs = pci_alloc_irq_vectors(pdev, 1, 1, flags);
+
+	if (nvecs < 0)
+		return nvecs;
+
+	tp->irq_nvecs = nvecs;
+
+	return 0;
 }
 
 static void rtl_read_mac_address(struct rtl8169_private *tp,
@@ -6012,6 +6094,15 @@ static int rtl_init_phylink(struct rtl8169_private *tp)
 	return 0;
 }
 
+static void r8169_init_napi(struct rtl8169_private *tp)
+{
+	for (int i = 0; i < tp->irq_nvecs; i++) {
+		netif_napi_add(tp->dev, &tp->rtl8169_napi[i], rtl8169_poll);
+		netif_napi_set_irq(&tp->rtl8169_napi[i],
+				   pci_irq_vector(tp->pci_dev, i));
+	}
+}
+
 static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	const struct rtl_chip_info *chip;
@@ -6112,12 +6203,12 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	rtl_hw_reset(tp);
 
+	rtl_setup_rx_params(tp);
+
 	rc = rtl_alloc_irq(tp);
 	if (rc < 0)
 		return dev_err_probe(&pdev->dev, rc, "Can't allocate interrupt\n");
 
-	tp->irq = pci_irq_vector(pdev, 0);
-
 	INIT_WORK(&tp->wk.work, rtl_task);
 	disable_work(&tp->wk.work);
 
@@ -6125,8 +6216,6 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	dev->ethtool_ops = &rtl8169_ethtool_ops;
 
-	netif_napi_add(dev, &tp->napi, rtl8169_poll);
-
 	dev->hw_features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM |
 			   NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX;
 	dev->vlan_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO;
@@ -6187,6 +6276,10 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (jumbo_max)
 		dev->max_mtu = jumbo_max;
 
+	rc = netif_set_real_num_queues(tp->dev, 1, tp->num_rx_rings);
+	if (rc < 0)
+		return dev_err_probe(&pdev->dev, rc, "set tx/rx num failure\n");
+
 	rtl_set_irq_mask(tp);
 
 	tp->counters = dmam_alloc_coherent (&pdev->dev, sizeof(*tp->counters),
@@ -6209,10 +6302,19 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		}
 	}
 
+	tp->rtl8169_napi = kcalloc(tp->irq_nvecs, sizeof(struct napi_struct),
+				   GFP_KERNEL);
+	if (!tp->rtl8169_napi) {
+		phylink_destroy(tp->phylink);
+		return -ENOMEM;
+	}
+
+	r8169_init_napi(tp);
+
 	rc = register_netdev(dev);
 	if (rc) {
 		phylink_destroy(tp->phylink);
-		return rc;
+		goto err_free_napi;
 	}
 
 	if (IS_ENABLED(CONFIG_R8169_LEDS)) {
@@ -6222,8 +6324,9 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 			tp->leds = rtl8168_init_leds(dev);
 	}
 
-	netdev_info(dev, "%s, %pM, %sXID %x, IRQ %d\n",
-		    chip->name, dev->dev_addr, ext_xid_str, xid, tp->irq);
+	netdev_info(dev, "%s, %pM, %sXID %x, IRQ %d (%u total)\n",
+		    chip->name, dev->dev_addr, ext_xid_str, xid,
+		    pci_irq_vector(pdev, 0), tp->irq_nvecs);
 
 	if (jumbo_max)
 		netdev_info(dev, "jumbo features [frames: %d bytes, tx checksumming: %s]\n",
@@ -6243,6 +6346,10 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		pm_runtime_put_sync(&pdev->dev);
 
 	return 0;
+
+err_free_napi:
+	r8169_free_napi(tp);
+	return rc;
 }
 
 static struct pci_driver rtl8169_pci_driver = {
-- 
2.43.0

[PATCH net-next v16 2/7] r8169: refactor RX path to prepare for multi-queue

[javen]

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

This patch is a preparatory refactoring of the RX path. It introduces
struct rtl8169_rx_ring and turns the previously embedded RX state in
rtl8169_private into a per-queue array.
The original DMA address of rx buffer is read back directly from
desc->addr. But when we enable rss, desc->addr will be overwritten. So
this patch introduces a array to cache the DMA address of rx buffers
which we name it as rx_buf_dma_addr.
While the netdev allocation is changed to devm_alloc_etherdev_mqs()
with up to 8 RX queues, the actual number of active RX rings
(num_rx_rings) is currently kept at 1. The actual multi-queue operation
and RSS enablement will be introduced in subsequent patches.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
Changes in v2:
 - sort some registers by its number
 - remove some unused definitions, like RX_DESC_RING_TYPE_MAX
 - change recheck_desc_ownbit type
 - remove rdsar_reg in rx_ring struct
 - opts1 are different in rx_desc and rx_desc_rss, move the judgement
   to Patch 5/7

Changes in v3:
 - remove ring->rx_desc_alloc_size, use constant instead

Changes in v4:
 - change rdsar_reg type to unsigned int
 - follow reverse xmas tree, in rtl_set_rx_tx_desc_registers(),
   rtl8169_alloc_rx_data(), rtl8169_alloc_rx_desc(),
   rtl8169_free_rx_desc()
 - add comments on LED_CTRL, remove helper function

Changes in v5:
 - modify rtl8169_init_ring(), do rx clear when failed
 - add definition R8169_MAX_TX_QUEUES 1

Changes in v6:
 - Restore the secondary Rx error filter when NETIF_F_RXFALL is enabled
   in rtl_rx()

Changes in v7:
 - remove code associated with recheck_desc_ownbit

Changes in v8:
 - remove le64_to_cpu() for addr, rx get addr from rx_desc_phy_addr

Changes in v9:
 - remove R8127_MAX_RX_QUEUES
 - remvoe rx_desc_ring_type to the following patch
 - Fix loop bound in init_ring_indexes
 - Restore checksum API

Changes in v10:
 - alloc rtl8169_rx_ring struct according to the num_rx_ring dynamically

Changes in v11:
 - leak rx_ring array on driver removal

Changes in v12:
 - no changes

Changes in v13:
 - remove unused dirty_rx

Changes in v14:
 - REvert R8169_RX_RING_BYTES padding changes. It will be split into a
   bugfix patch.
 - Fix phylink memory in rtl_init_one() by implementing a proper goto
   unwind laber (err_destory_phylink) for memory allocation failures.

Changes in v15:
 - no changes

Changes in v16:
 - modify commit message
 - delete blank line
 - correct misspelled label err_destory_phylink
 - rename rx_desc_phy_addr to rx_buf_dma_addr
---
 drivers/net/ethernet/realtek/r8169_main.c | 240 +++++++++++++++++-----
 1 file changed, 183 insertions(+), 57 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 3afb9a4b1aff..e88d512cc3a5 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -77,6 +77,9 @@
 #define R8169_RX_RING_BYTES	(NUM_RX_DESC * sizeof(struct RxDesc))
 #define R8169_TX_STOP_THRS	(MAX_SKB_FRAGS + 1)
 #define R8169_TX_START_THRS	(2 * R8169_TX_STOP_THRS)
+#define R8169_MAX_RX_QUEUES	8
+#define R8169_DEFAULT_RX_QUEUES	1
+#define R8169_MAX_TX_QUEUES	1
 
 #define OCP_STD_PHY_BASE	0xa400
 
@@ -463,6 +466,7 @@ enum rtl8125_registers {
 	TxPoll_8125		= 0x90,
 	LEDSEL3			= 0x96,
 	MAC0_BKP		= 0x19e0,
+	RDSAR_Q1_LOW		= 0x4000,
 	RSS_CTRL_8125		= 0x4500,
 	Q_NUM_CTRL_8125		= 0x4800,
 	EEE_TXIDLE_TIMER_8125	= 0x6048,
@@ -750,6 +754,14 @@ enum rtl_dash_type {
 	RTL_DASH_25_BP,
 };
 
+struct rtl8169_rx_ring {
+	u32 cur_rx;
+	struct RxDesc *rx_desc_array;
+	dma_addr_t rx_buf_dma_addr[NUM_RX_DESC];
+	dma_addr_t rx_phy_addr;
+	struct page *rx_databuff[NUM_RX_DESC];
+};
+
 enum rtl_sfp_mode {
 	RTL_SFP_NONE,
 	RTL_SFP_8168_AF,
@@ -764,20 +776,18 @@ struct rtl8169_private {
 	enum mac_version mac_version;
 	enum rtl_dash_type dash_type;
 	enum rtl_sfp_mode sfp_mode;
-	u32 cur_rx; /* Index into the Rx descriptor buffer of next Rx pkt. */
 	u32 cur_tx; /* Index into the Tx descriptor buffer of next Rx pkt. */
 	u32 dirty_tx;
 	struct TxDesc *TxDescArray;	/* 256-aligned Tx descriptor ring */
-	struct RxDesc *RxDescArray;	/* 256-aligned Rx descriptor ring */
 	dma_addr_t TxPhyAddr;
-	dma_addr_t RxPhyAddr;
-	struct page *Rx_databuff[NUM_RX_DESC];	/* Rx data buffers */
 	struct ring_info tx_skb[NUM_TX_DESC];	/* Tx data buffers */
 	struct napi_struct *rtl8169_napi;
+	struct rtl8169_rx_ring *rx_ring;
 	unsigned int num_rx_rings;
 	u16 cp_cmd;
 	u16 tx_lpi_timer;
 	u32 irq_mask;
+	unsigned int hw_supp_num_rx_queues;
 	unsigned int irq_nvecs;
 	struct clk *clk;
 	int speed;
@@ -2718,9 +2728,25 @@ static void rtl_init_rxcfg(struct rtl8169_private *tp)
 	}
 }
 
+static void rtl8169_rx_desc_init(struct rtl8169_private *tp)
+{
+	for (int i = 0; i < tp->num_rx_rings; i++) {
+		struct rtl8169_rx_ring *ring = &tp->rx_ring[i];
+
+		memset(ring->rx_desc_array, 0x0, R8169_RX_RING_BYTES);
+	}
+}
+
 static void rtl8169_init_ring_indexes(struct rtl8169_private *tp)
 {
-	tp->dirty_tx = tp->cur_tx = tp->cur_rx = 0;
+	tp->dirty_tx = 0;
+	tp->cur_tx = 0;
+
+	for (int i = 0; i < tp->num_rx_rings; i++) {
+		struct rtl8169_rx_ring *ring = &tp->rx_ring[i];
+
+		ring->cur_rx = 0;
+	}
 }
 
 static void rtl_jumbo_config(struct rtl8169_private *tp)
@@ -2773,6 +2799,14 @@ static void rtl_hw_reset(struct rtl8169_private *tp)
 static void rtl_setup_rx_params(struct rtl8169_private *tp)
 {
 	tp->num_rx_rings = 1;
+	switch (tp->mac_version) {
+	case RTL_GIGA_MAC_VER_80:
+		tp->hw_supp_num_rx_queues = R8169_MAX_RX_QUEUES;
+		break;
+	default:
+		tp->hw_supp_num_rx_queues = R8169_DEFAULT_RX_QUEUES;
+		break;
+	}
 }
 
 static void rtl_request_firmware(struct rtl8169_private *tp)
@@ -2899,6 +2933,8 @@ static void rtl_set_rx_max_size(struct rtl8169_private *tp)
 
 static void rtl_set_rx_tx_desc_registers(struct rtl8169_private *tp)
 {
+	struct rtl8169_rx_ring *ring = &tp->rx_ring[0];
+
 	/*
 	 * Magic spell: some iop3xx ARM board needs the TxDescAddrHigh
 	 * register to be written before TxDescAddrLow to work.
@@ -2906,8 +2942,18 @@ static void rtl_set_rx_tx_desc_registers(struct rtl8169_private *tp)
 	 */
 	RTL_W32(tp, TxDescStartAddrHigh, ((u64) tp->TxPhyAddr) >> 32);
 	RTL_W32(tp, TxDescStartAddrLow, ((u64) tp->TxPhyAddr) & DMA_BIT_MASK(32));
-	RTL_W32(tp, RxDescAddrHigh, ((u64) tp->RxPhyAddr) >> 32);
-	RTL_W32(tp, RxDescAddrLow, ((u64) tp->RxPhyAddr) & DMA_BIT_MASK(32));
+	RTL_W32(tp, RxDescAddrHigh, ((u64)ring->rx_phy_addr) >> 32);
+	RTL_W32(tp, RxDescAddrLow,
+		((u64)ring->rx_phy_addr) & DMA_BIT_MASK(32));
+
+	for (int i = 1; i < tp->num_rx_rings; i++) {
+		unsigned int rdsar_reg = RDSAR_Q1_LOW + (i - 1) * 8;
+		struct rtl8169_rx_ring *ring = &tp->rx_ring[i];
+
+		RTL_W32(tp, rdsar_reg + 4, ((u64)ring->rx_phy_addr >> 32));
+		RTL_W32(tp, rdsar_reg,
+			((u64)ring->rx_phy_addr) & DMA_BIT_MASK(32));
+	}
 }
 
 static void rtl8169_set_magic_reg(struct rtl8169_private *tp)
@@ -4330,8 +4376,9 @@ static void rtl8169_mark_to_asic(struct RxDesc *desc)
 }
 
 static struct page *rtl8169_alloc_rx_data(struct rtl8169_private *tp,
-					  struct RxDesc *desc)
+					  struct rtl8169_rx_ring *ring, unsigned int index)
 {
+	struct RxDesc *desc = ring->rx_desc_array + index;
 	struct device *d = tp_to_dev(tp);
 	int node = dev_to_node(d);
 	dma_addr_t mapping;
@@ -4349,55 +4396,107 @@ static struct page *rtl8169_alloc_rx_data(struct rtl8169_private *tp,
 	}
 
 	desc->addr = cpu_to_le64(mapping);
+	ring->rx_buf_dma_addr[index] = mapping;
 	rtl8169_mark_to_asic(desc);
 
 	return data;
 }
 
-static void rtl8169_rx_clear(struct rtl8169_private *tp)
+static void rtl8169_rx_clear(struct rtl8169_private *tp,
+			     struct rtl8169_rx_ring *ring)
 {
 	int i;
 
-	for (i = 0; i < NUM_RX_DESC && tp->Rx_databuff[i]; i++) {
+	for (i = 0; i < NUM_RX_DESC && ring->rx_databuff[i]; i++) {
 		dma_unmap_page(tp_to_dev(tp),
-			       le64_to_cpu(tp->RxDescArray[i].addr),
+			       ring->rx_buf_dma_addr[i],
 			       R8169_RX_BUF_SIZE, DMA_FROM_DEVICE);
-		__free_pages(tp->Rx_databuff[i], get_order(R8169_RX_BUF_SIZE));
-		tp->Rx_databuff[i] = NULL;
-		tp->RxDescArray[i].addr = 0;
-		tp->RxDescArray[i].opts1 = 0;
+		__free_pages(ring->rx_databuff[i], get_order(R8169_RX_BUF_SIZE));
+		ring->rx_databuff[i] = NULL;
+		ring->rx_buf_dma_addr[i] = 0;
+		ring->rx_desc_array[i].addr = 0;
+		ring->rx_desc_array[i].opts1 = 0;
 	}
 }
 
-static int rtl8169_rx_fill(struct rtl8169_private *tp)
+static int rtl8169_rx_fill(struct rtl8169_private *tp, struct rtl8169_rx_ring *ring)
 {
 	int i;
 
 	for (i = 0; i < NUM_RX_DESC; i++) {
 		struct page *data;
 
-		data = rtl8169_alloc_rx_data(tp, tp->RxDescArray + i);
+		data = rtl8169_alloc_rx_data(tp, ring, i);
 		if (!data) {
-			rtl8169_rx_clear(tp);
+			rtl8169_rx_clear(tp, ring);
 			return -ENOMEM;
 		}
-		tp->Rx_databuff[i] = data;
+		ring->rx_databuff[i] = data;
 	}
 
 	/* mark as last descriptor in the ring */
-	tp->RxDescArray[NUM_RX_DESC - 1].opts1 |= cpu_to_le32(RingEnd);
+	ring->rx_desc_array[NUM_RX_DESC - 1].opts1 |= cpu_to_le32(RingEnd);
 
 	return 0;
 }
 
+static int rtl8169_alloc_rx_desc(struct rtl8169_private *tp)
+{
+	struct pci_dev *pdev = tp->pci_dev;
+	struct rtl8169_rx_ring *ring;
+
+	for (int i = 0; i < tp->num_rx_rings; i++) {
+		ring = &tp->rx_ring[i];
+		ring->rx_desc_array = dma_alloc_coherent(&pdev->dev,
+							 R8169_RX_RING_BYTES,
+							 &ring->rx_phy_addr,
+							 GFP_KERNEL);
+		if (!ring->rx_desc_array)
+			return -ENOMEM;
+	}
+	return 0;
+}
+
+static void rtl8169_free_rx_desc(struct rtl8169_private *tp)
+{
+	struct pci_dev *pdev = tp->pci_dev;
+	struct rtl8169_rx_ring *ring;
+
+	for (int i = 0; i < tp->num_rx_rings; i++) {
+		ring = &tp->rx_ring[i];
+		if (ring->rx_desc_array) {
+			dma_free_coherent(&pdev->dev,
+					  R8169_RX_RING_BYTES,
+					  ring->rx_desc_array,
+					  ring->rx_phy_addr);
+			ring->rx_desc_array = NULL;
+		}
+	}
+}
+
 static int rtl8169_init_ring(struct rtl8169_private *tp)
 {
+	int i, ret;
+
 	rtl8169_init_ring_indexes(tp);
+	rtl8169_rx_desc_init(tp);
 
 	memset(tp->tx_skb, 0, sizeof(tp->tx_skb));
-	memset(tp->Rx_databuff, 0, sizeof(tp->Rx_databuff));
 
-	return rtl8169_rx_fill(tp);
+	for (i = 0; i < tp->num_rx_rings; i++) {
+		struct rtl8169_rx_ring *ring = &tp->rx_ring[i];
+
+		memset(ring->rx_databuff, 0, sizeof(ring->rx_databuff));
+		ret = rtl8169_rx_fill(tp, ring);
+		if (ret < 0)
+			goto err_clear;
+	}
+	return 0;
+
+err_clear:
+	while (--i >= 0)
+		rtl8169_rx_clear(tp, &tp->rx_ring[i]);
+	return ret;
 }
 
 static void rtl8169_unmap_tx_skb(struct rtl8169_private *tp, unsigned int entry)
@@ -4486,16 +4585,23 @@ static void rtl8169_cleanup(struct rtl8169_private *tp)
 	rtl8169_init_ring_indexes(tp);
 }
 
-static void rtl_reset_work(struct rtl8169_private *tp)
+static void rtl8169_rx_desc_reset(struct rtl8169_private *tp)
 {
-	int i;
+	for (int i = 0; i < tp->num_rx_rings; i++) {
+		struct rtl8169_rx_ring *ring = &tp->rx_ring[i];
 
+		for (int j = 0; j < NUM_RX_DESC; j++)
+			rtl8169_mark_to_asic(ring->rx_desc_array + j);
+	}
+}
+
+static void rtl_reset_work(struct rtl8169_private *tp)
+{
 	netif_stop_queue(tp->dev);
 
 	rtl8169_cleanup(tp);
 
-	for (i = 0; i < NUM_RX_DESC; i++)
-		rtl8169_mark_to_asic(tp->RxDescArray + i);
+	rtl8169_rx_desc_reset(tp);
 
 	rtl8169_napi_enable(tp);
 	rtl_hw_start(tp);
@@ -4951,15 +5057,30 @@ static inline void rtl8169_rx_csum(struct sk_buff *skb, u32 opts1)
 		skb_checksum_none_assert(skb);
 }
 
+static bool rtl8169_check_rx_desc_error(struct net_device *dev,
+					struct rtl8169_private *tp,
+					u32 status)
+{
+	if (unlikely(status & RxRES)) {
+		if (status & (RxRWT | RxRUNT))
+			dev->stats.rx_length_errors++;
+		if (status & RxCRC)
+			dev->stats.rx_crc_errors++;
+		return true;
+	}
+	return false;
+}
+
 static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
-		  int budget, struct napi_struct *napi)
+		  struct rtl8169_rx_ring *ring, int budget,
+		  struct napi_struct *napi)
 {
 	struct device *d = tp_to_dev(tp);
 	int count;
 
-	for (count = 0; count < budget; count++, tp->cur_rx++) {
-		unsigned int pkt_size, entry = tp->cur_rx % NUM_RX_DESC;
-		struct RxDesc *desc = tp->RxDescArray + entry;
+	for (count = 0; count < budget; count++, ring->cur_rx++) {
+		unsigned int pkt_size, entry = ring->cur_rx % NUM_RX_DESC;
+		struct RxDesc *desc = ring->rx_desc_array + entry;
 		struct sk_buff *skb;
 		const void *rx_buf;
 		dma_addr_t addr;
@@ -4975,15 +5096,11 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 		 */
 		dma_rmb();
 
-		if (unlikely(status & RxRES)) {
+		if (rtl8169_check_rx_desc_error(dev, tp, status)) {
 			if (net_ratelimit())
 				netdev_warn(dev, "Rx ERROR. status = %08x\n",
 					    status);
 			dev->stats.rx_errors++;
-			if (status & (RxRWT | RxRUNT))
-				dev->stats.rx_length_errors++;
-			if (status & RxCRC)
-				dev->stats.rx_crc_errors++;
 
 			if (!(dev->features & NETIF_F_RXALL))
 				goto release_descriptor;
@@ -5010,8 +5127,8 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 			goto release_descriptor;
 		}
 
-		addr = le64_to_cpu(desc->addr);
-		rx_buf = page_address(tp->Rx_databuff[entry]);
+		addr = ring->rx_buf_dma_addr[entry];
+		rx_buf = page_address(ring->rx_databuff[entry]);
 
 		dma_sync_single_for_cpu(d, addr, pkt_size, DMA_FROM_DEVICE);
 		prefetch(rx_buf);
@@ -5155,7 +5272,8 @@ static int rtl8169_poll(struct napi_struct *napi, int budget)
 
 	rtl_tx(dev, tp, budget);
 
-	work_done = rtl_rx(dev, tp, budget, napi);
+	/* rtl8169_poll() is used only when there is a single RX ring. */
+	work_done = rtl_rx(dev, tp, &tp->rx_ring[0], budget, napi);
 
 	if (work_done < budget && napi_complete_done(napi, work_done))
 		rtl_irq_enable(tp);
@@ -5255,18 +5373,17 @@ static int rtl8169_close(struct net_device *dev)
 	phylink_stop(tp->phylink);
 	netif_stop_queue(dev);
 	rtl8169_down(tp);
-	rtl8169_rx_clear(tp);
+	for (int i = 0; i < tp->num_rx_rings; i++)
+		rtl8169_rx_clear(tp, &tp->rx_ring[i]);
 
 	rtl8169_free_irq(tp);
 
 	phylink_disconnect_phy(tp->phylink);
 
-	dma_free_coherent(&pdev->dev, R8169_RX_RING_BYTES, tp->RxDescArray,
-			  tp->RxPhyAddr);
 	dma_free_coherent(&pdev->dev, R8169_TX_RING_BYTES, tp->TxDescArray,
 			  tp->TxPhyAddr);
 	tp->TxDescArray = NULL;
-	tp->RxDescArray = NULL;
+	rtl8169_free_rx_desc(tp);
 
 	pm_runtime_put_sync(&pdev->dev);
 
@@ -5300,10 +5417,8 @@ static int rtl_open(struct net_device *dev)
 	if (!tp->TxDescArray)
 		goto out;
 
-	tp->RxDescArray = dma_alloc_coherent(&pdev->dev, R8169_RX_RING_BYTES,
-					     &tp->RxPhyAddr, GFP_KERNEL);
-	if (!tp->RxDescArray)
-		goto err_free_tx_0;
+	if (rtl8169_alloc_rx_desc(tp) < 0)
+		goto err_free_rx_1;
 
 	retval = rtl8169_init_ring(tp);
 	if (retval < 0)
@@ -5333,12 +5448,10 @@ static int rtl_open(struct net_device *dev)
 	rtl8169_free_irq(tp);
 err_release_fw_2:
 	rtl_release_firmware(tp);
-	rtl8169_rx_clear(tp);
+	for (int i = 0; i < tp->num_rx_rings; i++)
+		rtl8169_rx_clear(tp, &tp->rx_ring[i]);
 err_free_rx_1:
-	dma_free_coherent(&pdev->dev, R8169_RX_RING_BYTES, tp->RxDescArray,
-			  tp->RxPhyAddr);
-	tp->RxDescArray = NULL;
-err_free_tx_0:
+	rtl8169_free_rx_desc(tp);
 	dma_free_coherent(&pdev->dev, R8169_TX_RING_BYTES, tp->TxDescArray,
 			  tp->TxPhyAddr);
 	tp->TxDescArray = NULL;
@@ -5505,6 +5618,7 @@ static void rtl_remove_one(struct pci_dev *pdev)
 
 	unregister_netdev(tp->dev);
 	r8169_free_napi(tp);
+	kfree(tp->rx_ring);
 	phylink_destroy(tp->phylink);
 
 	if (tp->dash_type != RTL_DASH_NONE)
@@ -6113,7 +6227,10 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	u32 txconfig;
 	u32 xid;
 
-	dev = devm_alloc_etherdev(&pdev->dev, sizeof (*tp));
+	dev = devm_alloc_etherdev_mqs(&pdev->dev, sizeof(*tp),
+				      R8169_MAX_TX_QUEUES,
+				      R8169_MAX_RX_QUEUES);
+
 	if (!dev)
 		return -ENOMEM;
 
@@ -6302,20 +6419,25 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		}
 	}
 
+	tp->rx_ring = kcalloc(tp->num_rx_rings, sizeof(struct rtl8169_rx_ring),
+			      GFP_KERNEL);
+	if (!tp->rx_ring) {
+		rc = -ENOMEM;
+		goto err_destroy_phylink;
+	}
+
 	tp->rtl8169_napi = kcalloc(tp->irq_nvecs, sizeof(struct napi_struct),
 				   GFP_KERNEL);
 	if (!tp->rtl8169_napi) {
-		phylink_destroy(tp->phylink);
-		return -ENOMEM;
+		rc = -ENOMEM;
+		goto err_free_rx_ring;
 	}
 
 	r8169_init_napi(tp);
 
 	rc = register_netdev(dev);
-	if (rc) {
-		phylink_destroy(tp->phylink);
+	if (rc)
 		goto err_free_napi;
-	}
 
 	if (IS_ENABLED(CONFIG_R8169_LEDS)) {
 		if (rtl_is_8125(tp))
@@ -6349,6 +6471,10 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 err_free_napi:
 	r8169_free_napi(tp);
+err_free_rx_ring:
+	kfree(tp->rx_ring);
+err_destroy_phylink:
+	phylink_destroy(tp->phylink);
 	return rc;
 }
 
-- 
2.43.0

[PATCH net-next v16 3/7] r8169: add support for new interrupt mapping

[javen]

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

To support RSS, the number of hardware interrupt bits should match the
interrupt of software. So we add support for new interrupt mapping here.
ISR_VEC_MAP_REG is the hardware register to indicate interrupt status.
IMR_SET_VEC_MAP_REG is interrupt mask which is set to enable irq.

Note that this patch only adds the infrastructure. All of the new paths
are gated on tp->irq_nvecs > 1. At this stage, irq_nvecs is still 1, so
this code will remain inactive until the subsequent patch requsets
multiple MSI-X vectors.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
Changes in v2:
 - no changes

Changes in v3:
 - init index in napi_struct and get message_id from index
 - move rtl8169_disable_hw_interrupt_msix directly before the call to
   napi_schedule()
 - change the condition in rtl8169_request_irq when RTL_VEC_MAP_ENABLE
   enabled, use rtl8169_interrupt_msix

Changes in v4:
 - remove flag tp->feature, replace tp->features & RTL_VEC_MAP_ENABLE
   with tp->irq_nvecs > 1, they are equivalent.
 - follow reverse xmas tree, in rtl8169_interrupt_msix(),
   rtl8169_poll_msix_rx(), rtl8169_poll_msix_tx(),
   rtl8169_poll_msix_other()
 - use napi->index in rtl8169_poll_msix_other()
 - add a comment to describe RTL8127 MSI-X vector layout
 - simplify r8169_init_napi()

Changes in v5:
 - replace magic number in rtl8169_poll_msix_tx()

Changes in v6:
 - when irq_nvecs <= 1, use register IntrMask_8125, else using vec map
 - fix irq sequence in rtl8169_interrupt_msix(), disable interrupts
   before clean it
 - remove dead code in rtl8169_poll_msix_tx()

Changes in v7:
 - remove recheck_desc_ownbit
 - change return value of rtl_tx
 - remove message_id which only used once

Changes in v8:
 - fix rtl8169_netpoll()
 - remove tx_done

Changes in v9:
 - change the way of getting message_id of napi

Changes in v10:
 - no changes

Changes in v11:
 - add comment on rtl8169_poll_msix_tx, only use 1 tx
 - remove napi for other. Separate napi only for datapath, control path
   like linkchg is handled in interrupt function, which will not call
   napi any more.

Changes in v12:
 - no changes

Changes in v13:
 - only request IRQs and napi for active vectors(0~7 rx, 8 tx)

Changes in v14:
 - fix tp->phydev null pointer issue when the nic is fiber mode

Changes in v15:
 - use new API netif_napi_add_tx() for tx queue
 - add a budget != 0 check before calling napi_complete_done()
 - refactor NAPI init, enable, disable, delete and rtl8169_netpoll() to
   only iterate over actually active rx and tx ring

Changes in v16:
 - modify commit message
 - request rx irq according to tp->num_rx_rings instead of R8169_MAX_RX_QUEUES
---
 drivers/net/ethernet/realtek/r8169_main.c | 244 ++++++++++++++++++----
 1 file changed, 209 insertions(+), 35 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index e88d512cc3a5..caa5f2880c6a 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -470,8 +470,12 @@ enum rtl8125_registers {
 	RSS_CTRL_8125		= 0x4500,
 	Q_NUM_CTRL_8125		= 0x4800,
 	EEE_TXIDLE_TIMER_8125	= 0x6048,
+	IMR_CLEAR_VEC_MAP_REG	= 0x0d00,
+	ISR_VEC_MAP_REG		= 0x0d04,
+	IMR_SET_VEC_MAP_REG	= 0x0d0c,
 };
 
+#define MSIX_ID_VEC_MAP_LINKCHG	29
 #define LEDSEL_MASK_8125	0x23f
 
 #define RX_VLAN_INNER_8125	BIT(22)
@@ -602,6 +606,9 @@ enum rtl_register_content {
 
 	/* magic enable v2 */
 	MagicPacket_v2	= (1 << 16),	/* Wake up when receives a Magic Packet */
+#define	ISRIMR_LINKCHG	BIT(29)
+#define	ISRIMR_TOK_Q0	BIT(8)
+#define	ISRIMR_ROK_Q0	BIT(0)
 };
 
 enum rtl_desc_bit {
@@ -1769,26 +1776,38 @@ static u32 rtl_get_events(struct rtl8169_private *tp)
 
 static void rtl_ack_events(struct rtl8169_private *tp, u32 bits)
 {
-	if (rtl_is_8125(tp))
-		RTL_W32(tp, IntrStatus_8125, bits);
-	else
+	if (rtl_is_8125(tp)) {
+		if (tp->irq_nvecs > 1)
+			RTL_W32(tp, ISR_VEC_MAP_REG, bits);
+		else
+			RTL_W32(tp, IntrStatus_8125, bits);
+	} else {
 		RTL_W16(tp, IntrStatus, bits);
+	}
 }
 
 static void rtl_irq_disable(struct rtl8169_private *tp)
 {
-	if (rtl_is_8125(tp))
-		RTL_W32(tp, IntrMask_8125, 0);
-	else
+	if (rtl_is_8125(tp)) {
+		if (tp->irq_nvecs > 1)
+			RTL_W32(tp, IMR_CLEAR_VEC_MAP_REG, 0xffffffff);
+		else
+			RTL_W32(tp, IntrMask_8125, 0);
+	} else {
 		RTL_W16(tp, IntrMask, 0);
+	}
 }
 
 static void rtl_irq_enable(struct rtl8169_private *tp)
 {
-	if (rtl_is_8125(tp))
-		RTL_W32(tp, IntrMask_8125, tp->irq_mask);
-	else
+	if (rtl_is_8125(tp)) {
+		if (tp->irq_nvecs > 1)
+			RTL_W32(tp, IMR_SET_VEC_MAP_REG, tp->irq_mask);
+		else
+			RTL_W32(tp, IntrMask_8125, tp->irq_mask);
+	} else {
 		RTL_W16(tp, IntrMask, tp->irq_mask);
+	}
 }
 
 static void rtl8169_irq_mask_and_ack(struct rtl8169_private *tp)
@@ -4538,14 +4557,24 @@ static void rtl8169_tx_clear(struct rtl8169_private *tp)
 
 static void rtl8169_napi_disable(struct rtl8169_private *tp)
 {
-	for (int i = 0; i < tp->irq_nvecs; i++)
-		napi_disable(&tp->rtl8169_napi[i]);
+	if (tp->irq_nvecs > 1) {
+		for (int i = 0; i < tp->num_rx_rings; i++)
+			napi_disable(&tp->rtl8169_napi[i]);
+		napi_disable(&tp->rtl8169_napi[R8169_MAX_RX_QUEUES]);
+	} else {
+		napi_disable(&tp->rtl8169_napi[0]);
+	}
 }
 
 static void rtl8169_napi_enable(struct rtl8169_private *tp)
 {
-	for (int i = 0; i < tp->irq_nvecs; i++)
-		napi_enable(&tp->rtl8169_napi[i]);
+	if (tp->irq_nvecs > 1) {
+		for (int i = 0; i < tp->num_rx_rings; i++)
+			napi_enable(&tp->rtl8169_napi[i]);
+		napi_enable(&tp->rtl8169_napi[R8169_MAX_RX_QUEUES]);
+	} else {
+		napi_enable(&tp->rtl8169_napi[0]);
+	}
 }
 
 static void rtl8169_cleanup(struct rtl8169_private *tp)
@@ -5190,19 +5219,81 @@ static irqreturn_t rtl8169_interrupt(int irq, void *dev_instance)
 	return IRQ_HANDLED;
 }
 
-static void rtl8169_free_irq(struct rtl8169_private *tp)
+static void rtl8169_free_one_irq(struct rtl8169_private *tp, int i)
 {
 	struct pci_dev *pdev = tp->pci_dev;
-	int i, irq;
+	struct napi_struct *napi;
+	int irq;
 
-	for (i = 0; i < tp->irq_nvecs; i++) {
-		struct napi_struct *napi = &tp->rtl8169_napi[i];
+	irq = pci_irq_vector(pdev, i);
+	napi = &tp->rtl8169_napi[i];
 
-		irq = pci_irq_vector(pdev, i);
+	if (tp->irq_nvecs > 1) {
+		if (i < tp->num_rx_rings || i == R8169_MAX_RX_QUEUES)
+			free_irq(irq, napi);
+		else if (i == MSIX_ID_VEC_MAP_LINKCHG)
+			free_irq(irq, tp);
+	} else {
 		free_irq(irq, napi);
 	}
 }
 
+static void rtl8169_free_irq(struct rtl8169_private *tp)
+{
+	int i;
+
+	for (i = 0; i < tp->irq_nvecs; i++)
+		rtl8169_free_one_irq(tp, i);
+}
+
+static void rtl8169_disable_hw_interrupt_msix(struct rtl8169_private *tp,
+					      int message_id)
+{
+	RTL_W32(tp, IMR_CLEAR_VEC_MAP_REG, BIT(message_id));
+}
+
+static void rtl8169_clear_hw_isr(struct rtl8169_private *tp, int message_id)
+{
+	RTL_W32(tp, ISR_VEC_MAP_REG, BIT(message_id));
+}
+
+static void rtl8169_enable_hw_interrupt_msix(struct rtl8169_private *tp,
+					     int message_id)
+{
+	RTL_W32(tp, IMR_SET_VEC_MAP_REG, BIT(message_id));
+}
+
+static irqreturn_t rtl8169_interrupt_msix(int irq, void *dev_instance)
+{
+	struct napi_struct *napi = dev_instance;
+	struct net_device *dev = napi->dev;
+	struct rtl8169_private *tp;
+	int message_id;
+
+	tp = netdev_priv(dev);
+	message_id = napi - tp->rtl8169_napi;
+
+	rtl8169_disable_hw_interrupt_msix(tp, message_id);
+	rtl8169_clear_hw_isr(tp, message_id);
+
+	napi_schedule(napi);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t rtl8169_interrupt_other(int irq, void *dev_instance)
+{
+	struct rtl8169_private *tp = dev_instance;
+
+	rtl8169_clear_hw_isr(tp, MSIX_ID_VEC_MAP_LINKCHG);
+	if (tp->phydev)
+		phy_mac_interrupt(tp->phydev);
+	else if (tp->sfp_mode)
+		phylink_mac_change(tp->phylink,
+				   !!(RTL_R8(tp, PHYstatus) & LinkStatus));
+	return IRQ_HANDLED;
+}
+
 static int rtl8169_request_irq(struct rtl8169_private *tp)
 {
 	struct pci_dev *pdev = tp->pci_dev;
@@ -5217,18 +5308,28 @@ static int rtl8169_request_irq(struct rtl8169_private *tp)
 		napi = &tp->rtl8169_napi[i];
 		irq = pci_irq_vector(pdev, i);
 
-		rc = request_irq(irq, rtl8169_interrupt, irqflags,
-				 dev->name, napi);
+		if (tp->irq_nvecs > 1) {
+			/* RX: 0~7, TX: 8*/
+			if (i < tp->num_rx_rings || i == R8169_MAX_RX_QUEUES)
+				rc = request_irq(irq, rtl8169_interrupt_msix,
+						 irqflags, dev->name, napi);
+			else if (i == MSIX_ID_VEC_MAP_LINKCHG)
+				rc = request_irq(irq, rtl8169_interrupt_other,
+						 irqflags, dev->name, tp);
+			else
+				continue;
+		} else {
+			rc = request_irq(irq, rtl8169_interrupt,
+					 irqflags, dev->name, napi);
+		}
 		if (rc)
 			goto free_irq;
 	}
 	return 0;
 
 free_irq:
-	while (--i >= 0) {
-		irq = pci_irq_vector(pdev, i);
-		free_irq(irq, &tp->rtl8169_napi[i]);
-	}
+	while (--i >= 0)
+		rtl8169_free_one_irq(tp, i);
 	return rc;
 }
 
@@ -5395,8 +5496,13 @@ static void rtl8169_netpoll(struct net_device *dev)
 {
 	struct rtl8169_private *tp = netdev_priv(dev);
 
-	for (int i = 0; i < tp->irq_nvecs; i++)
-		rtl8169_interrupt(0, &tp->rtl8169_napi[i]);
+	if (tp->irq_nvecs > 1) {
+		for (int i = 0; i < tp->num_rx_rings; i++)
+			rtl8169_interrupt_msix(0, &tp->rtl8169_napi[i]);
+		rtl8169_interrupt_msix(0, &tp->rtl8169_napi[R8169_MAX_RX_QUEUES]);
+	} else {
+		rtl8169_interrupt(0, &tp->rtl8169_napi[0]);
+	}
 }
 #endif
 
@@ -5598,8 +5704,13 @@ static void rtl_shutdown(struct pci_dev *pdev)
 
 static void r8169_free_napi(struct rtl8169_private *tp)
 {
-	for (int i = 0; i < tp->irq_nvecs; i++)
-		netif_napi_del(&tp->rtl8169_napi[i]);
+	if (tp->irq_nvecs > 1) {
+		for (int i = 0; i < tp->num_rx_rings; i++)
+			netif_napi_del(&tp->rtl8169_napi[i]);
+		netif_napi_del(&tp->rtl8169_napi[R8169_MAX_RX_QUEUES]);
+	} else {
+		netif_napi_del(&tp->rtl8169_napi[0]);
+	}
 
 	kfree(tp->rtl8169_napi);
 }
@@ -5652,10 +5763,16 @@ static const struct net_device_ops rtl_netdev_ops = {
 
 static void rtl_set_irq_mask(struct rtl8169_private *tp)
 {
-	tp->irq_mask = RxOK | RxErr | TxOK | TxErr | LinkChg;
+	if (tp->irq_nvecs > 1) {
+		tp->irq_mask = ISRIMR_LINKCHG | ISRIMR_TOK_Q0;
+		for (int i = 0; i < tp->num_rx_rings; i++)
+			tp->irq_mask |= ISRIMR_ROK_Q0 << i;
+	} else {
+		tp->irq_mask = RxOK | RxErr | TxOK | TxErr | LinkChg;
 
-	if (tp->mac_version <= RTL_GIGA_MAC_VER_06)
-		tp->irq_mask |= SYSErr | RxFIFOOver;
+		if (tp->mac_version <= RTL_GIGA_MAC_VER_06)
+			tp->irq_mask |= SYSErr | RxFIFOOver;
+	}
 }
 
 static int rtl_alloc_irq(struct rtl8169_private *tp)
@@ -6208,12 +6325,69 @@ static int rtl_init_phylink(struct rtl8169_private *tp)
 	return 0;
 }
 
+static int rtl8169_poll_msix_rx(struct napi_struct *napi, int budget)
+{
+	struct net_device *dev = napi->dev;
+	struct rtl8169_private *tp;
+	int work_done = 0;
+	int message_id;
+
+	tp = netdev_priv(dev);
+	message_id = napi - tp->rtl8169_napi;
+
+	if (message_id < tp->num_rx_rings)
+		work_done += rtl_rx(dev, tp, &tp->rx_ring[message_id],
+				    budget, napi);
+
+	if (work_done < budget && napi_complete_done(napi, work_done))
+		rtl8169_enable_hw_interrupt_msix(tp, message_id);
+
+	return work_done;
+}
+
+static int rtl8169_poll_msix_tx(struct napi_struct *napi, int budget)
+{
+	struct net_device *dev = napi->dev;
+	struct rtl8169_private *tp;
+
+	tp = netdev_priv(dev);
+
+	/* Currently r8169 only supports a single Tx ring.
+	 * Therefore, we don't need a per-ring Tx processing loop here.
+	 */
+	rtl_tx(dev, tp, budget);
+
+	if (budget && napi_complete_done(napi, 0))
+		rtl8169_enable_hw_interrupt_msix(tp, (int)(napi - tp->rtl8169_napi));
+
+	return 0;
+}
+
+/* RTL8127 MSI-X vector layout:
+ * Vectors 0 .. (MAX_RXQ - 1)			: Rx Queues
+ * Vectors MAX_RXQ .. (MAX_RXQ + MAX_TXQ - 1)	: Tx Queues
+ * NAPI is only allocated for data path
+ */
 static void r8169_init_napi(struct rtl8169_private *tp)
 {
-	for (int i = 0; i < tp->irq_nvecs; i++) {
-		netif_napi_add(tp->dev, &tp->rtl8169_napi[i], rtl8169_poll);
-		netif_napi_set_irq(&tp->rtl8169_napi[i],
-				   pci_irq_vector(tp->pci_dev, i));
+	int i;
+
+	if (tp->irq_nvecs > 1) {
+		for (i = 0; i < tp->num_rx_rings; i++) {
+			netif_napi_add(tp->dev, &tp->rtl8169_napi[i],
+				       rtl8169_poll_msix_rx);
+			netif_napi_set_irq(&tp->rtl8169_napi[i],
+					   pci_irq_vector(tp->pci_dev, i));
+		}
+		netif_napi_add_tx(tp->dev,
+				  &tp->rtl8169_napi[R8169_MAX_RX_QUEUES],
+				  rtl8169_poll_msix_tx);
+		netif_napi_set_irq(&tp->rtl8169_napi[R8169_MAX_RX_QUEUES],
+				   pci_irq_vector(tp->pci_dev, R8169_MAX_RX_QUEUES));
+	} else {
+		netif_napi_add(tp->dev, &tp->rtl8169_napi[0], rtl8169_poll);
+		netif_napi_set_irq(&tp->rtl8169_napi[0],
+				   pci_irq_vector(tp->pci_dev, 0));
 	}
 }
 
-- 
2.43.0

[PATCH net-next v16 4/7] r8169: prepare for new interrupt mapping

[javen]

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

This patch enables new interrupt mapping for RTL8127 and add error pkts
counter per ring.

Note that tp->irq_nvecs and tp->num_rx_rings are still hard-coded to 1.
The new mapping and multi-ring stats will actually become active in a
later patch that requests multiple MSI-X vector.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
Changes in v2:
 - no changes

Changes in v3:
 - no changes

Changes in v4:
 - no changes

Changes in v5:
 - no changes

Changes in v6:
 - no changes

Changes in v7:
 - no changes

Changes in v8:
 - no changes

Changes in v9:
 - no changes

Changes in v10:
 - no changes

Changes in v11:
 - add error pkts counter per ring

Changes in v12:
 - drop unrelated change in rtl8169_init_ring()

Changes in v13:
 - no changes

Changes in v14:
 - no changes

Changes in v15:
 - no changes

Changes in v16:
 - modify commit message
---
 drivers/net/ethernet/realtek/r8169_main.c | 78 +++++++++++++++++++----
 1 file changed, 67 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index caa5f2880c6a..76f7a4592deb 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -30,6 +30,7 @@
 #include <linux/prefetch.h>
 #include <linux/ipv6.h>
 #include <linux/unaligned.h>
+#include <linux/u64_stats_sync.h>
 #include <net/ip6_checksum.h>
 #include <net/netdev_queues.h>
 
@@ -767,6 +768,15 @@ struct rtl8169_rx_ring {
 	dma_addr_t rx_buf_dma_addr[NUM_RX_DESC];
 	dma_addr_t rx_phy_addr;
 	struct page *rx_databuff[NUM_RX_DESC];
+
+	struct {
+		u64 rx_errors;
+		u64 rx_dropped;
+		u64 rx_length_errors;
+		u64 rx_crc_errors;
+		u64 multicast;
+		struct u64_stats_sync syncp;
+	} stats;
 };
 
 enum rtl_sfp_mode {
@@ -4083,6 +4093,15 @@ DECLARE_RTL_COND(rtl_mac_ocp_e00e_cond)
 	return r8168_mac_ocp_read(tp, 0xe00e) & BIT(13);
 }
 
+static void rtl8169_hw_enable_vec_mapping(struct rtl8169_private *tp)
+{
+	u8 tmp;
+
+	tmp = RTL_R8(tp, INT_CFG0_8125);
+	tmp |= INT_CFG0_ENABLE_8125;
+	RTL_W8(tp, INT_CFG0_8125, tmp);
+}
+
 static void rtl_hw_start_8125_common(struct rtl8169_private *tp)
 {
 	rtl_pcie_state_l2l3_disable(tp);
@@ -4091,6 +4110,9 @@ static void rtl_hw_start_8125_common(struct rtl8169_private *tp)
 	RTL_W32(tp, RSS_CTRL_8125, 0);
 	RTL_W16(tp, Q_NUM_CTRL_8125, 0);
 
+	if (tp->irq_nvecs > 1)
+		rtl8169_hw_enable_vec_mapping(tp);
+
 	/* disable UPS */
 	r8168_mac_ocp_modify(tp, 0xd40a, 0x0010, 0x0000);
 
@@ -5086,15 +5108,16 @@ static inline void rtl8169_rx_csum(struct sk_buff *skb, u32 opts1)
 		skb_checksum_none_assert(skb);
 }
 
-static bool rtl8169_check_rx_desc_error(struct net_device *dev,
-					struct rtl8169_private *tp,
+static bool rtl8169_check_rx_desc_error(struct rtl8169_rx_ring *ring,
 					u32 status)
 {
 	if (unlikely(status & RxRES)) {
+		u64_stats_update_begin(&ring->stats.syncp);
 		if (status & (RxRWT | RxRUNT))
-			dev->stats.rx_length_errors++;
+			ring->stats.rx_length_errors++;
 		if (status & RxCRC)
-			dev->stats.rx_crc_errors++;
+			ring->stats.rx_crc_errors++;
+		u64_stats_update_end(&ring->stats.syncp);
 		return true;
 	}
 	return false;
@@ -5125,11 +5148,13 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 		 */
 		dma_rmb();
 
-		if (rtl8169_check_rx_desc_error(dev, tp, status)) {
+		if (rtl8169_check_rx_desc_error(ring, status)) {
 			if (net_ratelimit())
 				netdev_warn(dev, "Rx ERROR. status = %08x\n",
 					    status);
-			dev->stats.rx_errors++;
+			u64_stats_update_begin(&ring->stats.syncp);
+			ring->stats.rx_errors++;
+			u64_stats_update_end(&ring->stats.syncp);
 
 			if (!(dev->features & NETIF_F_RXALL))
 				goto release_descriptor;
@@ -5145,14 +5170,18 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 		 * They are seen as a symptom of over-mtu sized frames.
 		 */
 		if (unlikely(rtl8169_fragmented_frame(status))) {
-			dev->stats.rx_dropped++;
-			dev->stats.rx_length_errors++;
+			u64_stats_update_begin(&ring->stats.syncp);
+			ring->stats.rx_dropped++;
+			ring->stats.rx_length_errors++;
+			u64_stats_update_end(&ring->stats.syncp);
 			goto release_descriptor;
 		}
 
 		skb = napi_alloc_skb(napi, pkt_size);
 		if (unlikely(!skb)) {
-			dev->stats.rx_dropped++;
+			u64_stats_update_begin(&ring->stats.syncp);
+			ring->stats.rx_dropped++;
+			u64_stats_update_end(&ring->stats.syncp);
 			goto release_descriptor;
 		}
 
@@ -5171,8 +5200,11 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 
 		rtl8169_rx_vlan_tag(desc, skb);
 
-		if (skb->pkt_type == PACKET_MULTICAST)
-			dev->stats.multicast++;
+		if (skb->pkt_type == PACKET_MULTICAST) {
+			u64_stats_update_begin(&ring->stats.syncp);
+			ring->stats.multicast++;
+			u64_stats_update_end(&ring->stats.syncp);
+		}
 
 		napi_gro_receive(napi, skb);
 
@@ -5576,6 +5608,27 @@ rtl8169_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
 	netdev_stats_to_stats64(stats, &dev->stats);
 	dev_fetch_sw_netstats(stats, dev->tstats);
 
+	for (int i = 0; i < tp->num_rx_rings; i++) {
+		u64 errors, dropped, length_errors, crc_errors, multicast;
+		struct rtl8169_rx_ring *ring = &tp->rx_ring[i];
+		unsigned int start;
+
+		do {
+			start = u64_stats_fetch_begin(&ring->stats.syncp);
+			errors = ring->stats.rx_errors;
+			dropped = ring->stats.rx_dropped;
+			length_errors = ring->stats.rx_length_errors;
+			crc_errors = ring->stats.rx_crc_errors;
+			multicast = ring->stats.multicast;
+		} while (u64_stats_fetch_retry(&ring->stats.syncp, start));
+
+		stats->rx_errors += errors;
+		stats->rx_dropped += dropped;
+		stats->rx_length_errors += length_errors;
+		stats->rx_crc_errors += crc_errors;
+		stats->multicast += multicast;
+	}
+
 	/*
 	 * Fetch additional counter values missing in stats collected by driver
 	 * from tally counters.
@@ -6600,6 +6653,9 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto err_destroy_phylink;
 	}
 
+	for (int i = 0; i < tp->num_rx_rings; i++)
+		u64_stats_init(&tp->rx_ring[i].stats.syncp);
+
 	tp->rtl8169_napi = kcalloc(tp->irq_nvecs, sizeof(struct napi_struct),
 				   GFP_KERNEL);
 	if (!tp->rtl8169_napi) {
-- 
2.43.0

[PATCH net-next v16 5/7] r8169: add support and enable rss

[javen]

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

This patch adds support and enable rss for RTL8127. It requests 30 to 32
MSI-X vectors. To support RSS, this patch converts struct RxDesc into a
union.

Additionly, this patch fixes a potential skb overrun issue. Previously,
with NETIF_F_RXALL enabled, a runt or CRC-error desc with a length below
4 would fall through to subtract ETH_FCS_LEN. This will lead to a memory
overrun. Fix this by explicitly dropping packets smaller than ETH_HLEN +
ETH_FCS_LEN. Note that this fix introduces a behavior change on non-RSS
chips: with both RXALL and RXFCS enabled, runt frames of 14 to 17 bytes
that used to be delivered are now dropped.

Ethtool rss tools will be contained in another series patched instead of
this patch.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
Changes in v2:
 - some changes moved from Patch 2/7

Changes in v3:
 - add struct rtl8169_rss_data. Allocate it dynamically when needed.
 - define rss_key as an u32 array
 - replace some magic bit numbers in rtl8169_set_rss_hash_opt() and
   rtl8125_set_rx_q_num()
 - use union to combine different rx descriptor, refactor struct RxDesc
 - remove dead code from rtl8169_double_check_rss_support()

Changes in v4:
 - rename macro definition, e.g R8127_MAX_IRQ to R8127_MAX_NUM_IRQVEC
 - change hw_supp_indir_tbl_entries type to unsigned int
 - change init_rx_desc_type type to enum
 - remove rtl_check_rss_support(), add helper function
   rtl_hw_support_rss()
 - remove hw_curr_isr_ver, use irq_nvecs to judge whether we should
   enable vector interrupt mapping, use tp->num_rx_ring to judge whether
   we should enable rss
 - remove function rtl8169_double_check_rss_support(), use
   rtl8169_set_rx_ring_num() to set num_rx_ring according to tp->irq_nvecs

Changes in v5:
 - no changes

Changes in v6:
 - change rss_queue_num type from u8 to unsigned int
 - fix rx desc clear in rtl8169_rx_clear() for different desc type
 - clamping num_rx_ring with rounddown_pow_of_two()

Changes in v7:
 - remove unused macro
 - change unfixed type in rtl8169_store_reta

Changes in v8:
 - refill desc->addr when rx_desc reset
 - rtl8169_set_channels fixed in patch 7/7

Changes in v9:
 - remove rtl8169_set_desc_dma_addr, only set desc dma addr for
   RX_DESC_TYPE_RSS desc

Changes in v10:
 - Change rss_key to u8 array and write rss_key_reg as u32 values.
   Use get_unaligned_le32() to keep behavior consistent on big-endian
   and little-endian

Changes in v11:
 - fix compilation error by adding block in switch default case
 - fix concurrency bug on updating global dev->stats by using per-queue
   stat
 - fix packet drop logic to properlly handle fatal errors when rss is
   enable
 - use get_unaligned_le32() uniformly in rtl8169_store_reta()
 - fix coding style issues
 - add comment on pci_alloc_irq_vectors() call

Changes in v12:
 - add support for UDP rss

Changes in v13:
 - no changes

Changes in v14:
 - fix an integer underflow in rtl_rx() when handling extremely small
   RUNT packets with RXALL enabled.
 - remove redundant macro definition such as RX_RUNT_RSS/RX_CRC_RSS

Changes in v15:
 - Add a comment to clarify that the RxRWT (over-length) error is
   omitted for it is not supported by this desc type
 - Increase the minimum packet size check to ETH_HLEN + ETH_FCS_LEN
 - Add skb_record_rx_queue() in rtl_rx() to ensure correct RPS behavior
 - Add a fallback dev_info log when MSI-X vector allocation fails to
   meet 30-vector requerement

Changes in v16:
 - modify commit message
 - fix fallback path when fail to allocate nvecs
---
 drivers/net/ethernet/realtek/r8169_main.c | 418 ++++++++++++++++++++--
 1 file changed, 380 insertions(+), 38 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 76f7a4592deb..671a20c6e39a 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -81,6 +81,19 @@
 #define R8169_MAX_RX_QUEUES	8
 #define R8169_DEFAULT_RX_QUEUES	1
 #define R8169_MAX_TX_QUEUES	1
+#define R8127_MAX_NUM_IRQVEC	32
+#define R8127_MIN_NUM_IRQVEC	30
+#define R8169_IRQ_DEFAULT	1
+#define RTL_RSS_KEY_SIZE	40
+#define RSS_CPU_NUM_MASK	GENMASK(18, 16)
+#define RSS_HASH_MASK		GENMASK(10, 8)
+#define RTL_MAX_INDIRECTION_TABLE_ENTRIES 128
+#define RXS_RSS_UDP		BIT(27)
+#define RXS_RSS_IPV4		BIT(28)
+#define RXS_RSS_IPV6		BIT(29)
+#define RXS_RSS_TCP		BIT(30)
+#define RXS_RSS_L3_TYPE_MASK	(RXS_RSS_IPV4 | RXS_RSS_IPV6)
+#define RXS_RSS_L4_TYPE_MASK	(RXS_RSS_TCP | RXS_RSS_UDP)
 
 #define OCP_STD_PHY_BASE	0xa400
 
@@ -505,6 +518,9 @@ enum rtl_register_content {
 	RxRUNT	= (1 << 20),
 	RxCRC	= (1 << 19),
 
+	RXRUNT_RSS	= (1 << 21),
+	RXCRC_RSS	= (1 << 20),
+
 	/* ChipCmdBits */
 	StopReq		= 0x80,
 	CmdReset	= 0x10,
@@ -610,6 +626,20 @@ enum rtl_register_content {
 #define	ISRIMR_LINKCHG	BIT(29)
 #define	ISRIMR_TOK_Q0	BIT(8)
 #define	ISRIMR_ROK_Q0	BIT(0)
+#define RTL_DESC_TYPE_CTRL		0xd8
+#define RSS_KEY_REG			0x4600
+#define RSS_INDIRECTION_TBL_REG		0x4700
+#define RSS_CTRL_TCP_IPV4_SUPP		BIT(0)
+#define RTL_DESC_TYPE_RSS		BIT(1)
+#define RSS_CTRL_IPV4_SUPP		BIT(1)
+#define RSS_CTRL_TCP_IPV6_SUPP		BIT(2)
+#define RSS_CTRL_IPV6_SUPP		BIT(3)
+#define RSS_CTRL_IPV6_EXT_SUPP		BIT(4)
+#define RSS_CTRL_TCP_IPV6_EXT_SUPP	BIT(5)
+#define RSS_CTRL_UDP_IPV4_SUPP		BIT(11)
+#define RSS_CTRL_UDP_IPV6_SUPP		BIT(12)
+#define	RX_RES_RSS			BIT(22)
+#define RTL_RX_Q_NUM_MASK		GENMASK(4, 2)
 };
 
 enum rtl_desc_bit {
@@ -667,6 +697,11 @@ enum rtl_rx_desc_bit {
 #define RxProtoIP	(PID1 | PID0)
 #define RxProtoMask	RxProtoIP
 
+#define	RX_UDPT_DESC_RSS	BIT(19)
+#define	RX_TCPT_DESC_RSS	BIT(18)
+#define	RX_UDPF_DESC_RSS	BIT(16) /* UDP/IP checksum failed */
+#define	RX_TCPF_DESC_RSS	BIT(15) /* TCP/IP checksum failed */
+
 	IPFail		= (1 << 16), /* IP checksum failed */
 	UDPFail		= (1 << 15), /* UDP/IP checksum failed */
 	TCPFail		= (1 << 14), /* TCP/IP checksum failed */
@@ -688,9 +723,27 @@ struct TxDesc {
 };
 
 struct RxDesc {
-	__le32 opts1;
-	__le32 opts2;
-	__le64 addr;
+	union {
+		/* RX_DESC_TYPE_DEFAULT */
+		struct {
+			__le32 opts1;
+			__le32 opts2;
+			__le64 addr;
+		};
+
+		/* RX_DESC_TYPE_RSS */
+		struct {
+			union {
+				__le64 rss_addr;
+				struct {
+					__le32 rss_info;
+					__le32 rss_result;
+				} rss_dword;
+			};
+			__le32 rss_opts2;
+			__le32 rss_opts1;
+		};
+	};
 };
 
 struct ring_info {
@@ -762,6 +815,11 @@ enum rtl_dash_type {
 	RTL_DASH_25_BP,
 };
 
+enum rx_desc_type {
+	RX_DESC_TYPE_DEFAULT,
+	RX_DESC_TYPE_RSS,
+};
+
 struct rtl8169_rx_ring {
 	u32 cur_rx;
 	struct RxDesc *rx_desc_array;
@@ -785,6 +843,12 @@ enum rtl_sfp_mode {
 	RTL_SFP_8127_ATF,
 };
 
+struct rtl8169_rss_data {
+	u8 rss_key[RTL_RSS_KEY_SIZE];
+	u8 rss_indir_tbl[RTL_MAX_INDIRECTION_TABLE_ENTRIES];
+	unsigned int hw_supp_indir_tbl_entries;
+};
+
 struct rtl8169_private {
 	void __iomem *mmio_addr;	/* memory map physical address */
 	struct pci_dev *pci_dev;
@@ -805,7 +869,9 @@ struct rtl8169_private {
 	u16 tx_lpi_timer;
 	u32 irq_mask;
 	unsigned int hw_supp_num_rx_queues;
+	struct rtl8169_rss_data *rss_data;
 	unsigned int irq_nvecs;
+	enum rx_desc_type init_rx_desc_type;
 	struct clk *clk;
 	int speed;
 
@@ -1720,6 +1786,11 @@ static enum rtl_sfp_mode rtl_get_sfp_mode(struct rtl8169_private *tp)
 	return RTL_SFP_NONE;
 }
 
+static bool rtl_hw_support_rss(struct rtl8169_private *tp)
+{
+	return tp->mac_version == RTL_GIGA_MAC_VER_80;
+}
+
 static enum rtl_dash_type rtl_get_dash_type(struct rtl8169_private *tp)
 {
 	switch (tp->mac_version) {
@@ -2019,9 +2090,20 @@ static inline u32 rtl8169_tx_vlan_tag(struct sk_buff *skb)
 		TxVlanTag | swab16(skb_vlan_tag_get(skb)) : 0x00;
 }
 
-static void rtl8169_rx_vlan_tag(struct RxDesc *desc, struct sk_buff *skb)
+static void rtl8169_rx_vlan_tag(struct rtl8169_private *tp,
+				struct RxDesc *desc,
+				struct sk_buff *skb)
 {
-	u32 opts2 = le32_to_cpu(desc->opts2);
+	u32 opts2;
+
+	switch (tp->init_rx_desc_type) {
+	case RX_DESC_TYPE_RSS:
+		opts2 = le32_to_cpu(desc->rss_opts2);
+		break;
+	default:
+		opts2 = le32_to_cpu(desc->opts2);
+		break;
+	}
 
 	if (opts2 & RxVlanTag)
 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), swab16(opts2 & 0xffff));
@@ -2825,17 +2907,27 @@ static void rtl_hw_reset(struct rtl8169_private *tp)
 	rtl_loop_wait_low(tp, &rtl_chipcmd_cond, 100, 100);
 }
 
+static void rtl8169_init_rss(struct rtl8169_private *tp)
+{
+	for (int i = 0; i < tp->rss_data->hw_supp_indir_tbl_entries; i++)
+		tp->rss_data->rss_indir_tbl[i] = ethtool_rxfh_indir_default(i, tp->num_rx_rings);
+
+	netdev_rss_key_fill(tp->rss_data->rss_key, RTL_RSS_KEY_SIZE);
+}
+
 static void rtl_setup_rx_params(struct rtl8169_private *tp)
 {
 	tp->num_rx_rings = 1;
 	switch (tp->mac_version) {
 	case RTL_GIGA_MAC_VER_80:
 		tp->hw_supp_num_rx_queues = R8169_MAX_RX_QUEUES;
+		tp->rss_data->hw_supp_indir_tbl_entries = RTL_MAX_INDIRECTION_TABLE_ENTRIES;
 		break;
 	default:
 		tp->hw_supp_num_rx_queues = R8169_DEFAULT_RX_QUEUES;
 		break;
 	}
+	tp->init_rx_desc_type = RX_DESC_TYPE_DEFAULT;
 }
 
 static void rtl_request_firmware(struct rtl8169_private *tp)
@@ -2960,6 +3052,58 @@ static void rtl_set_rx_max_size(struct rtl8169_private *tp)
 	RTL_W16(tp, RxMaxSize, R8169_RX_BUF_SIZE + 1);
 }
 
+static void rtl8169_store_rss_key(struct rtl8169_private *tp)
+{
+	u8 *rss_key = tp->rss_data->rss_key;
+	const u16 rss_key_reg = RSS_KEY_REG;
+
+	/* Write RSS key to HW */
+	for (int i = 0; i < RTL_RSS_KEY_SIZE; i += sizeof(u32))
+		RTL_W32(tp, rss_key_reg + i, get_unaligned_le32(rss_key + i));
+}
+
+static void rtl8169_store_reta(struct rtl8169_private *tp)
+{
+	u8 *indir_tbl = tp->rss_data->rss_indir_tbl;
+	unsigned int i;
+
+	/* Write redirection table to HW */
+	for (i = 0; i < tp->rss_data->hw_supp_indir_tbl_entries; i += 4) {
+		u32 reta = get_unaligned_le32(&indir_tbl[i]);
+
+		RTL_W32(tp, RSS_INDIRECTION_TBL_REG + i, reta);
+	}
+}
+
+static void rtl8169_set_rss_hash_opt(struct rtl8169_private *tp)
+{
+	u32 rss_ctrl;
+
+	rss_ctrl = FIELD_PREP(RSS_CPU_NUM_MASK, ilog2(tp->num_rx_rings));
+
+	/* Perform hash on these packet types */
+	rss_ctrl |= RSS_CTRL_TCP_IPV4_SUPP |
+		    RSS_CTRL_IPV4_SUPP |
+		    RSS_CTRL_IPV6_SUPP |
+		    RSS_CTRL_IPV6_EXT_SUPP |
+		    RSS_CTRL_TCP_IPV6_SUPP |
+		    RSS_CTRL_TCP_IPV6_EXT_SUPP |
+		    RSS_CTRL_UDP_IPV4_SUPP |
+		    RSS_CTRL_UDP_IPV6_SUPP;
+
+	rss_ctrl |= FIELD_PREP(RSS_HASH_MASK,
+			       ilog2(tp->rss_data->hw_supp_indir_tbl_entries));
+
+	RTL_W32(tp, RSS_CTRL_8125, rss_ctrl);
+}
+
+static void rtl_set_rss_config(struct rtl8169_private *tp)
+{
+	rtl8169_set_rss_hash_opt(tp);
+	rtl8169_store_reta(tp);
+	rtl8169_store_rss_key(tp);
+}
+
 static void rtl_set_rx_tx_desc_registers(struct rtl8169_private *tp)
 {
 	struct rtl8169_rx_ring *ring = &tp->rx_ring[0];
@@ -4093,6 +4237,18 @@ DECLARE_RTL_COND(rtl_mac_ocp_e00e_cond)
 	return r8168_mac_ocp_read(tp, 0xe00e) & BIT(13);
 }
 
+static void rtl8125_set_rx_q_num(struct rtl8169_private *tp)
+{
+	u16 rx_q_num;
+	u16 q_ctrl;
+
+	rx_q_num = ilog2(tp->num_rx_rings);
+	q_ctrl = RTL_R16(tp, Q_NUM_CTRL_8125);
+	q_ctrl &= ~RTL_RX_Q_NUM_MASK;
+	q_ctrl |= FIELD_PREP(RTL_RX_Q_NUM_MASK, rx_q_num);
+	RTL_W16(tp, Q_NUM_CTRL_8125, q_ctrl);
+}
+
 static void rtl8169_hw_enable_vec_mapping(struct rtl8169_private *tp)
 {
 	u8 tmp;
@@ -4132,6 +4288,13 @@ static void rtl_hw_start_8125_common(struct rtl8169_private *tp)
 	    tp->mac_version == RTL_GIGA_MAC_VER_80)
 		RTL_W8(tp, 0xD8, RTL_R8(tp, 0xD8) & ~0x02);
 
+	/* enable rx descriptor type v4 and set queue num for rss */
+	if (tp->num_rx_rings > 1) {
+		rtl8125_set_rx_q_num(tp);
+		RTL_W8(tp, RTL_DESC_TYPE_CTRL,
+		       RTL_R8(tp, RTL_DESC_TYPE_CTRL) | RTL_DESC_TYPE_RSS);
+	}
+
 	if (tp->mac_version == RTL_GIGA_MAC_VER_80)
 		r8168_mac_ocp_modify(tp, 0xe614, 0x0f00, 0x0f00);
 	else if (tp->mac_version == RTL_GIGA_MAC_VER_70)
@@ -4368,6 +4531,12 @@ static void rtl_hw_start(struct  rtl8169_private *tp)
 	rtl_hw_aspm_clkreq_enable(tp, true);
 	rtl_set_rx_max_size(tp);
 	rtl_set_rx_tx_desc_registers(tp);
+	if (rtl_is_8125(tp)) {
+		if (tp->num_rx_rings > 1)
+			rtl_set_rss_config(tp);
+		else
+			RTL_W32(tp, RSS_CTRL_8125, 0x00);
+	}
 	rtl_lock_config_regs(tp);
 
 	rtl_jumbo_config(tp);
@@ -4406,14 +4575,26 @@ static int rtl8169_change_mtu(struct net_device *dev, int new_mtu)
 	return 0;
 }
 
-static void rtl8169_mark_to_asic(struct RxDesc *desc)
+static void rtl8169_mark_to_asic(struct rtl8169_private *tp, struct RxDesc *desc)
 {
-	u32 eor = le32_to_cpu(desc->opts1) & RingEnd;
+	u32 eor;
 
-	desc->opts2 = 0;
-	/* Force memory writes to complete before releasing descriptor */
-	dma_wmb();
-	WRITE_ONCE(desc->opts1, cpu_to_le32(DescOwn | eor | R8169_RX_BUF_SIZE));
+	switch (tp->init_rx_desc_type) {
+	case RX_DESC_TYPE_RSS:
+		eor = le32_to_cpu(desc->rss_opts1) & RingEnd;
+		desc->rss_opts2 = cpu_to_le32(0);
+		/* Force memory writes to complete before releasing descriptor */
+		dma_wmb();
+		WRITE_ONCE(desc->rss_opts1, cpu_to_le32(DescOwn | eor | R8169_RX_BUF_SIZE));
+		break;
+	default:
+		eor = le32_to_cpu(desc->opts1) & RingEnd;
+		desc->opts2 = cpu_to_le32(0);
+		/* Force memory writes to complete before releasing descriptor */
+		dma_wmb();
+		WRITE_ONCE(desc->opts1, cpu_to_le32(DescOwn | eor | R8169_RX_BUF_SIZE));
+		break;
+	}
 }
 
 static struct page *rtl8169_alloc_rx_data(struct rtl8169_private *tp,
@@ -4436,9 +4617,12 @@ static struct page *rtl8169_alloc_rx_data(struct rtl8169_private *tp,
 		return NULL;
 	}
 
-	desc->addr = cpu_to_le64(mapping);
 	ring->rx_buf_dma_addr[index] = mapping;
-	rtl8169_mark_to_asic(desc);
+	if (tp->init_rx_desc_type == RX_DESC_TYPE_RSS)
+		desc->rss_addr = cpu_to_le64(mapping);
+	else
+		desc->addr = cpu_to_le64(mapping);
+	rtl8169_mark_to_asic(tp, desc);
 
 	return data;
 }
@@ -4455,8 +4639,25 @@ static void rtl8169_rx_clear(struct rtl8169_private *tp,
 		__free_pages(ring->rx_databuff[i], get_order(R8169_RX_BUF_SIZE));
 		ring->rx_databuff[i] = NULL;
 		ring->rx_buf_dma_addr[i] = 0;
-		ring->rx_desc_array[i].addr = 0;
-		ring->rx_desc_array[i].opts1 = 0;
+		if (tp->init_rx_desc_type == RX_DESC_TYPE_RSS) {
+			ring->rx_desc_array[i].rss_addr = 0;
+			ring->rx_desc_array[i].rss_opts1 = 0;
+		} else {
+			ring->rx_desc_array[i].addr = 0;
+			ring->rx_desc_array[i].opts1 = 0;
+		}
+	}
+}
+
+static void rtl8169_mark_as_last_descriptor(struct rtl8169_private *tp, struct RxDesc *desc)
+{
+	switch (tp->init_rx_desc_type) {
+	case RX_DESC_TYPE_RSS:
+		desc->rss_opts1 |= cpu_to_le32(RingEnd);
+		break;
+	default:
+		desc->opts1 |= cpu_to_le32(RingEnd);
+		break;
 	}
 }
 
@@ -4476,7 +4677,7 @@ static int rtl8169_rx_fill(struct rtl8169_private *tp, struct rtl8169_rx_ring *r
 	}
 
 	/* mark as last descriptor in the ring */
-	ring->rx_desc_array[NUM_RX_DESC - 1].opts1 |= cpu_to_le32(RingEnd);
+	rtl8169_mark_as_last_descriptor(tp, &ring->rx_desc_array[NUM_RX_DESC - 1]);
 
 	return 0;
 }
@@ -4641,8 +4842,13 @@ static void rtl8169_rx_desc_reset(struct rtl8169_private *tp)
 	for (int i = 0; i < tp->num_rx_rings; i++) {
 		struct rtl8169_rx_ring *ring = &tp->rx_ring[i];
 
-		for (int j = 0; j < NUM_RX_DESC; j++)
-			rtl8169_mark_to_asic(ring->rx_desc_array + j);
+		for (int j = 0; j < NUM_RX_DESC; j++) {
+			dma_addr_t phy_addr = ring->rx_buf_dma_addr[j];
+
+			if (tp->init_rx_desc_type == RX_DESC_TYPE_RSS)
+				ring->rx_desc_array[j].rss_addr = cpu_to_le64(phy_addr);
+			rtl8169_mark_to_asic(tp, ring->rx_desc_array + j);
+		}
 	}
 }
 
@@ -5098,27 +5304,95 @@ static inline int rtl8169_fragmented_frame(u32 status)
 	return (status & (FirstFrag | LastFrag)) != (FirstFrag | LastFrag);
 }
 
-static inline void rtl8169_rx_csum(struct sk_buff *skb, u32 opts1)
+static void rtl8169_rx_hash(struct rtl8169_private *tp,
+			    struct RxDesc *desc,
+			    struct sk_buff *skb)
 {
-	u32 status = opts1 & (RxProtoMask | RxCSFailMask);
+	u32 rss_header_info;
+	u32 hash_val;
+
+	if (!(tp->dev->features & NETIF_F_RXHASH))
+		return;
+
+	rss_header_info = le32_to_cpu(desc->rss_dword.rss_info);
+
+	if (!(rss_header_info & RXS_RSS_L3_TYPE_MASK))
+		return;
+
+	hash_val = le32_to_cpu(desc->rss_dword.rss_result);
+
+	skb_set_hash(skb, hash_val,
+		     (RXS_RSS_L4_TYPE_MASK & rss_header_info) ?
+		     PKT_HASH_TYPE_L4 : PKT_HASH_TYPE_L3);
+}
+
+static void rtl8169_rx_csum(struct rtl8169_private *tp,
+			    struct sk_buff *skb,
+			    u32 opts1)
+{
+	bool csum_ok = false;
+
+	switch (tp->init_rx_desc_type) {
+	case RX_DESC_TYPE_RSS:
+		if (((opts1 & RX_TCPT_DESC_RSS) && !(opts1 & RX_TCPF_DESC_RSS)) ||
+		    ((opts1 & RX_UDPT_DESC_RSS) && !(opts1 & RX_UDPF_DESC_RSS)))
+			csum_ok = true;
+		break;
+	default: {
+		u32 status = opts1 & (RxProtoMask | RxCSFailMask);
+
+		if (status == RxProtoTCP || status == RxProtoUDP)
+			csum_ok = true;
+		break;
+	}
+	}
 
-	if (status == RxProtoTCP || status == RxProtoUDP)
+	if (csum_ok)
 		skb->ip_summed = CHECKSUM_UNNECESSARY;
 	else
 		skb_checksum_none_assert(skb);
 }
 
+static __le32 rtl8169_rx_desc_opts1(struct rtl8169_private *tp, struct RxDesc *desc)
+{
+	switch (tp->init_rx_desc_type) {
+	case RX_DESC_TYPE_RSS:
+		return READ_ONCE(desc->rss_opts1);
+	default:
+		return READ_ONCE(desc->opts1);
+	}
+}
+
 static bool rtl8169_check_rx_desc_error(struct rtl8169_rx_ring *ring,
+					struct rtl8169_private *tp,
 					u32 status)
 {
-	if (unlikely(status & RxRES)) {
-		u64_stats_update_begin(&ring->stats.syncp);
-		if (status & (RxRWT | RxRUNT))
-			ring->stats.rx_length_errors++;
-		if (status & RxCRC)
-			ring->stats.rx_crc_errors++;
-		u64_stats_update_end(&ring->stats.syncp);
-		return true;
+	switch (tp->init_rx_desc_type) {
+	case RX_DESC_TYPE_RSS:
+		if (unlikely(status & RX_RES_RSS)) {
+			u64_stats_update_begin(&ring->stats.syncp);
+
+			/* Note: The RTL8127 RSS descriptor layout does not have
+			 * an RxRWT (Receive Watchdog Timer / over-length) bit.
+			 */
+			if (status & RXRUNT_RSS)
+				ring->stats.rx_length_errors++;
+			if (status & RXCRC_RSS)
+				ring->stats.rx_crc_errors++;
+			u64_stats_update_end(&ring->stats.syncp);
+			return true;
+		}
+		break;
+	default:
+		if (unlikely(status & RxRES)) {
+			u64_stats_update_begin(&ring->stats.syncp);
+			if (status & (RxRWT | RxRUNT))
+				ring->stats.rx_length_errors++;
+			if (status & RxCRC)
+				ring->stats.rx_crc_errors++;
+			u64_stats_update_end(&ring->stats.syncp);
+			return true;
+		}
 	}
 	return false;
 }
@@ -5138,7 +5412,7 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 		dma_addr_t addr;
 		u32 status;
 
-		status = le32_to_cpu(READ_ONCE(desc->opts1));
+		status = le32_to_cpu(rtl8169_rx_desc_opts1(tp, desc));
 		if (status & DescOwn)
 			break;
 
@@ -5148,7 +5422,7 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 		 */
 		dma_rmb();
 
-		if (rtl8169_check_rx_desc_error(ring, status)) {
+		if (rtl8169_check_rx_desc_error(ring, tp, status)) {
 			if (net_ratelimit())
 				netdev_warn(dev, "Rx ERROR. status = %08x\n",
 					    status);
@@ -5158,11 +5432,21 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 
 			if (!(dev->features & NETIF_F_RXALL))
 				goto release_descriptor;
-			else if (status & RxRWT || !(status & (RxRUNT | RxCRC)))
-				goto release_descriptor;
+
+			if (tp->init_rx_desc_type == RX_DESC_TYPE_DEFAULT) {
+				if (status & RxRWT || !(status & (RxRUNT | RxCRC)))
+					goto release_descriptor;
+			} else {
+				if (!(status & (RXRUNT_RSS | RXCRC_RSS)))
+					goto release_descriptor;
+			}
 		}
 
 		pkt_size = status & GENMASK(13, 0);
+
+		if (unlikely(pkt_size < ETH_HLEN + ETH_FCS_LEN))
+			goto release_descriptor;
+
 		if (likely(!(dev->features & NETIF_F_RXFCS)))
 			pkt_size -= ETH_FCS_LEN;
 
@@ -5195,10 +5479,14 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 		skb->len = pkt_size;
 		dma_sync_single_for_device(d, addr, pkt_size, DMA_FROM_DEVICE);
 
-		rtl8169_rx_csum(skb, status);
+		if (tp->num_rx_rings > 1) {
+			rtl8169_rx_hash(tp, desc, skb);
+			skb_record_rx_queue(skb, ring - tp->rx_ring);
+		}
+		rtl8169_rx_csum(tp, skb, status);
 		skb->protocol = eth_type_trans(skb, dev);
 
-		rtl8169_rx_vlan_tag(desc, skb);
+		rtl8169_rx_vlan_tag(tp, desc, skb);
 
 		if (skb->pkt_type == PACKET_MULTICAST) {
 			u64_stats_update_begin(&ring->stats.syncp);
@@ -5210,7 +5498,9 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
 
 		dev_sw_netstats_rx_add(dev, pkt_size);
 release_descriptor:
-		rtl8169_mark_to_asic(desc);
+		if (tp->init_rx_desc_type == RX_DESC_TYPE_RSS)
+			desc->rss_addr = cpu_to_le64(ring->rx_buf_dma_addr[entry]);
+		rtl8169_mark_to_asic(tp, desc);
 	}
 
 	return count;
@@ -5828,11 +6118,39 @@ static void rtl_set_irq_mask(struct rtl8169_private *tp)
 	}
 }
 
+static int get_max_irq_nvecs(struct rtl8169_private *tp)
+{
+	if (tp->mac_version == RTL_GIGA_MAC_VER_80)
+		return R8127_MAX_NUM_IRQVEC;
+	return R8169_IRQ_DEFAULT;
+}
+
+static int get_min_irq_nvecs(struct rtl8169_private *tp)
+{
+	if (tp->mac_version == RTL_GIGA_MAC_VER_80)
+		return R8127_MIN_NUM_IRQVEC;
+	return R8169_IRQ_DEFAULT;
+}
+
+static void rtl8169_set_rx_ring_num(struct rtl8169_private *tp)
+{
+	if (tp->irq_nvecs >= get_min_irq_nvecs(tp)) {
+		unsigned int rss_queue_num = netif_get_num_default_rss_queues();
+
+		tp->num_rx_rings = rounddown_pow_of_two(min(rss_queue_num,
+							    tp->hw_supp_num_rx_queues));
+		if (tp->num_rx_rings >= 2)
+			tp->init_rx_desc_type = RX_DESC_TYPE_RSS;
+	}
+}
+
 static int rtl_alloc_irq(struct rtl8169_private *tp)
 {
 	struct pci_dev *pdev = tp->pci_dev;
 	unsigned int flags;
-	int nvecs;
+	int nvecs, min_nvecs;
+
+	min_nvecs = get_min_irq_nvecs(tp);
 
 	switch (tp->mac_version) {
 	case RTL_GIGA_MAC_VER_02 ... RTL_GIGA_MAC_VER_06:
@@ -5848,7 +6166,14 @@ static int rtl_alloc_irq(struct rtl8169_private *tp)
 		break;
 	}
 
-	nvecs = pci_alloc_irq_vectors(pdev, 1, 1, flags);
+	nvecs = pci_alloc_irq_vectors(pdev, min_nvecs,
+				      get_max_irq_nvecs(tp), flags);
+
+	if (nvecs < 0 && min_nvecs > 1) {
+		dev_info(&pdev->dev, "Failed to allocate %d MSI-X vectors.\n",
+			 min_nvecs);
+		nvecs = pci_alloc_irq_vectors(pdev, 1, 1, flags);
+	}
 
 	if (nvecs < 0)
 		return nvecs;
@@ -6533,6 +6858,13 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	tp->dash_type = rtl_get_dash_type(tp);
 	tp->dash_enabled = rtl_dash_is_enabled(tp);
 
+	if (rtl_hw_support_rss(tp)) {
+		tp->rss_data = devm_kzalloc(&pdev->dev, sizeof(*tp->rss_data),
+					    GFP_KERNEL);
+		if (!tp->rss_data)
+			return -ENOMEM;
+	}
+
 	tp->cp_cmd = RTL_R16(tp, CPlusCmd) & CPCMD_MASK;
 
 	if (sizeof(dma_addr_t) > 4 && tp->mac_version >= RTL_GIGA_MAC_VER_18 &&
@@ -6553,6 +6885,11 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (rc < 0)
 		return dev_err_probe(&pdev->dev, rc, "Can't allocate interrupt\n");
 
+	rtl8169_set_rx_ring_num(tp);
+
+	if (rtl_hw_support_rss(tp))
+		rtl8169_init_rss(tp);
+
 	INIT_WORK(&tp->wk.work, rtl_task);
 	disable_work(&tp->wk.work);
 
@@ -6565,6 +6902,11 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	dev->vlan_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO;
 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 
+	if (rtl_hw_support_rss(tp) && tp->num_rx_rings > 1) {
+		dev->hw_features |= NETIF_F_RXHASH;
+		dev->features |= NETIF_F_RXHASH;
+	}
+
 	/*
 	 * Pretend we are using VLANs; This bypasses a nasty bug where
 	 * Interrupts stop flowing on high load on 8110SCd controllers.
-- 
2.43.0

[PATCH net-next v16 6/7] r8169: move struct ethtool_ops

[javen]

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

The patch moves the rtl8169_ethtool_ops definition further down in
r8169_main.c so that subsequent additions of rtl8169_get_channels and
can be referenced from the ops struct without needing forward
declarations.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
Changes in v2:
 - no changes

Changes in v3:
 - no changes

Changes in v4:
 - no changes

Changes in v5:
 - no changes

Changes in v6:
 - modify commit message

Changes in v7:
 - no changes

Changes in v8:
 - no changes

Changes in v9:
 - no changes

Changes in v10:
 - no changes

Changes in v11:
 - no changes

Changes in v12:
 - no changes

Changes in v13:
 - no changes

Changes in v14:
 - no changes

Changes in v15:
 - no changes

Changes in v16:
 - no changes
---
 drivers/net/ethernet/realtek/r8169_main.c | 56 +++++++++++------------
 1 file changed, 28 insertions(+), 28 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 671a20c6e39a..de0c860328ba 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -2636,34 +2636,6 @@ static int rtl8169_nway_reset(struct net_device *dev)
 	return phylink_ethtool_nway_reset(tp->phylink);
 }
 
-static const struct ethtool_ops rtl8169_ethtool_ops = {
-	.supported_coalesce_params = ETHTOOL_COALESCE_USECS |
-				     ETHTOOL_COALESCE_MAX_FRAMES,
-	.get_drvinfo		= rtl8169_get_drvinfo,
-	.get_regs_len		= rtl8169_get_regs_len,
-	.get_link		= ethtool_op_get_link,
-	.get_coalesce		= rtl_get_coalesce,
-	.set_coalesce		= rtl_set_coalesce,
-	.get_regs		= rtl8169_get_regs,
-	.get_wol		= rtl8169_get_wol,
-	.set_wol		= rtl8169_set_wol,
-	.get_strings		= rtl8169_get_strings,
-	.get_sset_count		= rtl8169_get_sset_count,
-	.get_ethtool_stats	= rtl8169_get_ethtool_stats,
-	.get_ts_info		= ethtool_op_get_ts_info,
-	.nway_reset		= rtl8169_nway_reset,
-	.get_eee		= rtl8169_get_eee,
-	.set_eee		= rtl8169_set_eee,
-	.get_link_ksettings	= rtl8169_get_link_ksettings,
-	.set_link_ksettings	= rtl8169_set_link_ksettings,
-	.get_ringparam		= rtl8169_get_ringparam,
-	.get_pause_stats	= rtl8169_get_pause_stats,
-	.get_pauseparam		= rtl8169_get_pauseparam,
-	.set_pauseparam		= rtl8169_set_pauseparam,
-	.get_eth_mac_stats	= rtl8169_get_eth_mac_stats,
-	.get_eth_ctrl_stats	= rtl8169_get_eth_ctrl_stats,
-};
-
 static const struct rtl_chip_info *rtl8169_get_chip_version(u32 xid, bool gmii)
 {
 	/* Chips combining a 1Gbps MAC with a 100Mbps PHY */
@@ -6769,6 +6741,34 @@ static void r8169_init_napi(struct rtl8169_private *tp)
 	}
 }
 
+static const struct ethtool_ops rtl8169_ethtool_ops = {
+	.supported_coalesce_params = ETHTOOL_COALESCE_USECS |
+				     ETHTOOL_COALESCE_MAX_FRAMES,
+	.get_drvinfo		= rtl8169_get_drvinfo,
+	.get_regs_len		= rtl8169_get_regs_len,
+	.get_link		= ethtool_op_get_link,
+	.get_coalesce		= rtl_get_coalesce,
+	.set_coalesce		= rtl_set_coalesce,
+	.get_regs		= rtl8169_get_regs,
+	.get_wol		= rtl8169_get_wol,
+	.set_wol		= rtl8169_set_wol,
+	.get_strings		= rtl8169_get_strings,
+	.get_sset_count		= rtl8169_get_sset_count,
+	.get_ethtool_stats	= rtl8169_get_ethtool_stats,
+	.get_ts_info		= ethtool_op_get_ts_info,
+	.nway_reset		= rtl8169_nway_reset,
+	.get_eee		= rtl8169_get_eee,
+	.set_eee		= rtl8169_set_eee,
+	.get_link_ksettings	= rtl8169_get_link_ksettings,
+	.set_link_ksettings	= rtl8169_set_link_ksettings,
+	.get_ringparam		= rtl8169_get_ringparam,
+	.get_pause_stats	= rtl8169_get_pause_stats,
+	.get_pauseparam		= rtl8169_get_pauseparam,
+	.set_pauseparam		= rtl8169_set_pauseparam,
+	.get_eth_mac_stats	= rtl8169_get_eth_mac_stats,
+	.get_eth_ctrl_stats	= rtl8169_get_eth_ctrl_stats,
+};
+
 static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	const struct rtl_chip_info *chip;
-- 
2.43.0

[PATCH net-next v16 7/7] r8169: add get_channel support for ethtool

[javen]

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

Add get_channel support for ethtool.

In multi-vector mode, it reports the active RX channel count and a
single TX channel. Additionly, it reports one other channel to account
for the dedicated link-change interrupt vector.

In single-vector mode, where RX, TX, link-change events share the same
interrupt, it reports a single combined channel.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
---
Changes in v11:
 - new file, no change

Changes in v12:
 - no changes

Changes in v13:
 - no changes

Changes in v14:
 - no changes

Changes in v15:
 - no changes

Changes in v16:
 - modify commit message
 - add other msix count in get_channel function
---
 drivers/net/ethernet/realtek/r8169_main.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index de0c860328ba..88354e7570f0 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -6741,6 +6741,24 @@ 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);
+
+	if (tp->irq_nvecs > 1) {
+		ch->max_rx = tp->hw_supp_num_rx_queues;
+		ch->max_tx = 1;
+		ch->max_other = 1;
+		ch->rx_count = tp->num_rx_rings;
+		ch->tx_count = 1;
+		ch->other_count = 1;
+	} else {
+		ch->max_combined = 1;
+		ch->combined_count = 1;
+	}
+}
+
 static const struct ethtool_ops rtl8169_ethtool_ops = {
 	.supported_coalesce_params = ETHTOOL_COALESCE_USECS |
 				     ETHTOOL_COALESCE_MAX_FRAMES,
@@ -6759,6 +6777,7 @@ static const struct ethtool_ops rtl8169_ethtool_ops = {
 	.nway_reset		= rtl8169_nway_reset,
 	.get_eee		= rtl8169_get_eee,
 	.set_eee		= rtl8169_set_eee,
+	.get_channels		= rtl8169_get_channels,
 	.get_link_ksettings	= rtl8169_get_link_ksettings,
 	.set_link_ksettings	= rtl8169_set_link_ksettings,
 	.get_ringparam		= rtl8169_get_ringparam,
-- 
2.43.0

Re: [PATCH net-next v16 3/7] r8169: add support for new interrupt mapping

[netdev-bot+sashiko]

Thank you for your contribution! Sashiko AI review found more severe
issue(s) in other patches of this series. This mail is only an FYI, in case
you want to address the nit picks below when you respin.

Low priority / nit picks for your consideration:

- [Low] Baseline decision: false positive at the end of the series.
- [Low] Baseline decision: false positive at the end of the series.
- [Low] The comment above r8169_init_napi() in
  drivers/net/ethernet/realtek/r8169_main.c is inaccurate.
- [Low] Baseline decision: false positive at the end of the series.

--

r8169: add support for new interrupt mapping

This adds the infrastructure for the vector-map interrupt registers on
RTL8127, used for multi-vector MSI-X. It adds per-RX-ring and TX NAPI
poll handlers and a dedicated link-change vector. All of the new paths
are gated on tp->irq_nvecs > 1, which is still always 1 at this point in
the series.

> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> index e88d512cc3a56..caa5f2880c6a2 100644
> --- a/drivers/net/ethernet/realtek/r8169_main.c
> +++ b/drivers/net/ethernet/realtek/r8169_main.c

[ ... ]

> @@ -1769,26 +1776,38 @@ static u32 rtl_get_events(struct rtl8169_private *tp)

[ ... ]

>  static void rtl_irq_enable(struct rtl8169_private *tp)
>  {
> -	if (rtl_is_8125(tp))
> -		RTL_W32(tp, IntrMask_8125, tp->irq_mask);
> -	else
> +	if (rtl_is_8125(tp)) {
> +		if (tp->irq_nvecs > 1)
> +			RTL_W32(tp, IMR_SET_VEC_MAP_REG, tp->irq_mask);
> +		else
> +			RTL_W32(tp, IntrMask_8125, tp->irq_mask);
> +	} else {
>  		RTL_W16(tp, IntrMask, tp->irq_mask);
> +	}
>  }

[Severity: Low]
Does the chip need to be in vector-map mode before writes to
IMR_SET_VEC_MAP_REG, IMR_CLEAR_VEC_MAP_REG and ISR_VEC_MAP_REG take
effect?

In this commit nothing sets INT_CFG0_ENABLE_8125, and
rtl_hw_start_8125() clears the whole register:

rtl_hw_start_8125() {
    ...
	RTL_W8(tp, INT_CFG0_8125, 0x00);
    ...
}

This can't trigger here because irq_nvecs is always 1. The next patch
in the series, "r8169: prepare for new interrupt mapping", adds
rtl8169_hw_enable_vec_mapping(). That function sets INT_CFG0_ENABLE_8125
from rtl_hw_start_8125_common() when irq_nvecs > 1.

It runs after the clear above, through rtl_hw_config() ->
rtl_hw_start_8127a() -> rtl_hw_start_8125_common(), so the series as a
whole looks consistent.

Would it be worth saying in the commit message that vector-map mode is
enabled in a later patch?

[ ... ]

> @@ -6208,12 +6325,69 @@ static int rtl_init_phylink(struct rtl8169_private *tp)
>  	return 0;
>  }
>  
> +static int rtl8169_poll_msix_rx(struct napi_struct *napi, int budget)
> +{

[ ... ]

> +	if (message_id < tp->num_rx_rings)
> +		work_done += rtl_rx(dev, tp, &tp->rx_ring[message_id],
> +				    budget, napi);

[Severity: Low]
Once there is one of these NAPI instances per RX ring, could they run at
the same time on different CPUs? If so, they would race on the shared
dev->stats counters in rtl_rx():

rtl_rx() {
    ...
		if (unlikely(rtl8169_fragmented_frame(status))) {
			dev->stats.rx_dropped++;
			dev->stats.rx_length_errors++;
			goto release_descriptor;
    ...
		if (skb->pkt_type == PACKET_MULTICAST)
			dev->stats.multicast++;
    ...
}

rtl8169_check_rx_desc_error() increments dev->stats.rx_length_errors
and dev->stats.rx_crc_errors in the same way. These are plain
non-atomic increments, so concurrent writers could lose updates.

This can't happen in this commit because irq_nvecs is always 1. The
next patch, "r8169: prepare for new interrupt mapping", moves these
counters into per-ring ring->stats protected by u64_stats_sync. That
happens before "r8169: add support and enable rss" enables multiple RX
NAPIs.

[ ... ]

> +/* RTL8127 MSI-X vector layout:
> + * Vectors 0 .. (MAX_RXQ - 1)			: Rx Queues
> + * Vectors MAX_RXQ .. (MAX_RXQ + MAX_TXQ - 1)	: Tx Queues
> + * NAPI is only allocated for data path
> + */

[Severity: Low]
This isn't a bug, but is this comment accurate?

The layout leaves out the link-change vector MSIX_ID_VEC_MAP_LINKCHG
(29). rtl8169_request_irq() requests that vector with
rtl8169_interrupt_other(), and rtl8169_free_one_irq() frees it.

Also, rtl_init_one() allocates one napi_struct per vector:

	tp->rtl8169_napi = kcalloc(tp->irq_nvecs, sizeof(struct napi_struct),

Later in the series there are 30 to 32 vectors, but only
num_rx_rings + 1 of these entries are ever registered. So the NAPI
structs are allocated per vector and only registered for the data path.

The comment is still unchanged at the end of the series.

>  static void r8169_init_napi(struct rtl8169_private *tp)
>  {
> -	for (int i = 0; i < tp->irq_nvecs; i++) {
> -		netif_napi_add(tp->dev, &tp->rtl8169_napi[i], rtl8169_poll);
> -		netif_napi_set_irq(&tp->rtl8169_napi[i],
> -				   pci_irq_vector(tp->pci_dev, i));
> +	int i;
> +
> +	if (tp->irq_nvecs > 1) {
> +		for (i = 0; i < tp->num_rx_rings; i++) {
> +			netif_napi_add(tp->dev, &tp->rtl8169_napi[i],
> +				       rtl8169_poll_msix_rx);
> +			netif_napi_set_irq(&tp->rtl8169_napi[i],
> +					   pci_irq_vector(tp->pci_dev, i));
> +		}
> +		netif_napi_add_tx(tp->dev,
> +				  &tp->rtl8169_napi[R8169_MAX_RX_QUEUES],
> +				  rtl8169_poll_msix_tx);

[Severity: Low]
Is tp->rtl8169_napi[R8169_MAX_RX_QUEUES] always inside the array here?

The array is allocated with kcalloc(tp->irq_nvecs, ...), but the only
check is irq_nvecs > 1. With irq_nvecs between 2 and 8, index 8 would be
past the end of the array. That index is used here and in
rtl8169_napi_enable(), rtl8169_napi_disable(), r8169_free_napi() and
rtl8169_netpoll().

There is a similar gap for the link-change vector. rtl_set_irq_mask()
always arms ISRIMR_LINKCHG when irq_nvecs > 1. However,
rtl8169_request_irq() only installs rtl8169_interrupt_other() when the
loop reaches MSIX_ID_VEC_MAP_LINKCHG (29). With fewer than 30 vectors,
the link-change interrupt would have no handler.

As far as I can tell, neither case can happen anywhere in the series:

- In this commit, rtl_alloc_irq() calls
  pci_alloc_irq_vectors(pdev, 1, 1, flags).
- In "r8169: add support and enable rss", the minimum is 30 vectors
  for RTL_GIGA_MAC_VER_80, with a fallback to exactly 1 vector.

So irq_nvecs > 1 implies irq_nvecs >= 30.

Could this dependency be made explicit, with a check or a comment saying
multi-vector mode requires at least 30 vectors, rather than relying on
irq_nvecs > 1 alone?

[ ... ]

-- 
Sashiko AI review · https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20261008065722.1026-1-javen_xu%40realsil.com.cn

Re: [PATCH net-next v16 4/7] r8169: prepare for new interrupt mapping

[netdev-bot+sashiko]

Thank you for your contribution! Sashiko AI review found more severe
issue(s) in other patches of this series. This mail is only an FYI, in case
you want to address the nit picks below when you respin.

Low priority / nit picks for your consideration:

- [Low] The commit message understates what the patch changes.

--

r8169: prepare for new interrupt mapping

This patch adds rtl8169_hw_enable_vec_mapping() and calls it from
rtl_hw_start_8125_common() when more than one IRQ vector is in use. It
also moves the RX counters in rtl_rx() and rtl8169_check_rx_desc_error()
from dev->stats into new per-ring u64_stats_sync protected counters in
struct rtl8169_rx_ring, and rtl8169_get_stats64() now sums them.

> r8169: prepare for new interrupt mapping
>
> This patch enables new interrupt mapping for RTL8127 and add error pkts
> counter per ring.

[Severity: Low]

This isn't a bug, but could the subject and body describe the stats
change more precisely?

The subject only mentions interrupt mapping. The patch also moves every
RX counter in rtl_rx() and rtl8169_check_rx_desc_error() out of
dev->stats and into ring->stats. Those counters are rx_errors,
rx_dropped, rx_length_errors, rx_crc_errors and multicast.

The phrase "add error pkts counter per ring" suggests new counters, but
these are existing counters being moved. Also, multicast is not an error
counter:

drivers/net/ethernet/realtek/r8169_main.c:rtl_rx() {
    ...
		if (skb->pkt_type == PACKET_MULTICAST) {
			u64_stats_update_begin(&ring->stats.syncp);
			ring->stats.multicast++;
			u64_stats_update_end(&ring->stats.syncp);
		}
    ...
}

The stats change takes effect right away on every chip the driver
supports. The vector mapping only runs when tp->irq_nvecs is greater
than 1:

drivers/net/ethernet/realtek/r8169_main.c:rtl_hw_start_8125_common() {
    ...
	if (tp->irq_nvecs > 1)
		rtl8169_hw_enable_vec_mapping(tp);
    ...
}

That can't happen until a later patch, because rtl_alloc_irq() still
requests only one vector.

With num_rx_rings == 1, the values reported by rtl8169_get_stats64()
seem unchanged. The only problem is that the description does not match
the diff.

Would it make sense to put the stats conversion in its own patch? If
not, could the subject and body say that RX statistics accounting
changes for all r8169 chips?

-- 
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Re: [PATCH net-next v16 5/7] r8169: add support and enable rss

[netdev-bot+sashiko]

Thank you for your contribution! Sashiko AI review found 2 potential
issue(s) to consider.

Critical: 0 · High: 0 · Medium: 1 · Low: 1

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issue of Medium severity or higher and explain why the AI is wrong.
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know by including "pw-bot: cr" as a separate line at the end of your reply
(one such reply per series is enough).

- [Medium] The commit message says this patch fixes a memory overrun in
  rtl_rx() (drivers/net/ethernet/realtek/r8169_main.c) that happens with…
- [Low] On RTL8127 (RTL_GIGA_MAC_VER_80), rtl_alloc_irq() always calls
  pci_alloc_irq_vectors(pdev, 30, 32, flags) before…

--

r8169: add support and enable rss

This adds RSS support for RTL8127. The driver now requests 30 to 32 MSI-X
vectors and turns struct RxDesc into a union so it can handle the RSS
descriptor layout. It also adds a minimum length check in rtl_rx() for
runt and CRC-error frames received with NETIF_F_RXALL enabled.

> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> index 76f7a4592deb9..671a20c6e39a7 100644
> --- a/drivers/net/ethernet/realtek/r8169_main.c
> +++ b/drivers/net/ethernet/realtek/r8169_main.c

[ ... ]

> @@ -5158,11 +5432,21 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp,
>  
>  			if (!(dev->features & NETIF_F_RXALL))
>  				goto release_descriptor;
> -			else if (status & RxRWT || !(status & (RxRUNT | RxCRC)))
> -				goto release_descriptor;
> +
> +			if (tp->init_rx_desc_type == RX_DESC_TYPE_DEFAULT) {
> +				if (status & RxRWT || !(status & (RxRUNT | RxCRC)))
> +					goto release_descriptor;
> +			} else {
> +				if (!(status & (RXRUNT_RSS | RXCRC_RSS)))
> +					goto release_descriptor;
> +			}
>  		}
>  
>  		pkt_size = status & GENMASK(13, 0);
> +
> +		if (unlikely(pkt_size < ETH_HLEN + ETH_FCS_LEN))
> +			goto release_descriptor;
> +

[Severity: Medium]
The commit message says:

  Additionly, this patch fixes a potential skb overrun issue. Previously,
  with NETIF_F_RXALL enabled, a runt or CRC-error desc with a length below
  4 would fall through to subtract ETH_FCS_LEN. This will lead to a memory
  overrun.

The bug being fixed is already in mainline. In the current rtl_rx(), a
runt or CRC-error descriptor is not released when RXALL is on, so it
reaches this code with no minimum length check:

    pkt_size = status & GENMASK(13, 0);
    if (likely(!(dev->features & NETIF_F_RXFCS)))
        pkt_size -= ETH_FCS_LEN;

If the length is below 4, pkt_size wraps to about 4G. napi_alloc_skb()
then adds NET_SKB_PAD + NET_IP_ALIGN, which wraps the length back to a
small allocation. After that, skb_copy_to_linear_data() copies pkt_size
bytes, overrunning both the skb head and the RX page.

This check does not depend on RSS. Since it is part of a net-next feature
patch with no Fixes: tag or stable Cc, will stable kernels pick it up?

Could it be split into its own patch for the net tree, with a Fixes: tag
pointing at the commit that introduced the unchecked subtraction? The
logic looks like it comes from 588c7e5cc048 ("r8169: make rtl_rx better
readable") and ce11ff5e5963 ("r8169: fix vlan tag read ordering.").

>  		if (likely(!(dev->features & NETIF_F_RXFCS)))
>  			pkt_size -= ETH_FCS_LEN;
>  

[ ... ]

> @@ -5828,11 +6118,39 @@ static void rtl_set_irq_mask(struct rtl8169_private *tp)
>  	}
>  }
>  
> +static int get_max_irq_nvecs(struct rtl8169_private *tp)
> +{
> +	if (tp->mac_version == RTL_GIGA_MAC_VER_80)
> +		return R8127_MAX_NUM_IRQVEC;
> +	return R8169_IRQ_DEFAULT;
> +}
> +
> +static int get_min_irq_nvecs(struct rtl8169_private *tp)
> +{
> +	if (tp->mac_version == RTL_GIGA_MAC_VER_80)
> +		return R8127_MIN_NUM_IRQVEC;
> +	return R8169_IRQ_DEFAULT;
> +}
> +
> +static void rtl8169_set_rx_ring_num(struct rtl8169_private *tp)
> +{
> +	if (tp->irq_nvecs >= get_min_irq_nvecs(tp)) {
> +		unsigned int rss_queue_num = netif_get_num_default_rss_queues();
> +
> +		tp->num_rx_rings = rounddown_pow_of_two(min(rss_queue_num,
> +							    tp->hw_supp_num_rx_queues));
> +		if (tp->num_rx_rings >= 2)
> +			tp->init_rx_desc_type = RX_DESC_TYPE_RSS;
> +	}
> +}
> +

[ ... ]

> @@ -5848,7 +6166,14 @@ static int rtl_alloc_irq(struct rtl8169_private *tp)
>  		break;
>  	}
>  
> -	nvecs = pci_alloc_irq_vectors(pdev, 1, 1, flags);
> +	nvecs = pci_alloc_irq_vectors(pdev, min_nvecs,
> +				      get_max_irq_nvecs(tp), flags);

[Severity: Low]
On RTL8127 this always requests 30 to 32 vectors. The RX ring count is
chosen later, in rtl8169_set_rx_ring_num(). What happens when
netif_get_num_default_rss_queues() returns 1?

That function returns 1 unconditionally in a kdump kernel:

    if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL)))
        return 1;

It also returns 1 on a system with a single physical core. The result is
num_rx_rings = 1 and RX_DESC_TYPE_DEFAULT, so RSS stays off. irq_nvecs is
still around 32, though, so every irq_nvecs > 1 check still switches the
device to vector mapping mode, for example in rtl_hw_start_8125_common():

    if (tp->irq_nvecs > 1)
        rtl8169_hw_enable_vec_mapping(tp);

The same applies to the vector map registers in rtl_ack_events(),
rtl_irq_enable() and rtl_irq_disable(), the split NAPI setup in
r8169_init_napi(), and the per-vector handlers in rtl8169_request_irq().

Only a few of the allocated vectors are ever requested, so 27 to 29 stay
reserved and unused. In kdump this works against
netif_get_num_default_rss_queues() deliberately returning 1.

Should the ring count be decided before the vectors are allocated, or the
allocation fall back to a single vector when RSS will not be used? If the
current behavior is intended, could the commit message say that every
RTL8127 moves to vector mapping mode even when RSS stays off?

> +
> +	if (nvecs < 0 && min_nvecs > 1) {
> +		dev_info(&pdev->dev, "Failed to allocate %d MSI-X vectors.\n",
> +			 min_nvecs);
> +		nvecs = pci_alloc_irq_vectors(pdev, 1, 1, flags);
> +	}
>  
>  	if (nvecs < 0)
>  		return nvecs;

[ ... ]

-- 
Sashiko AI review · https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20261008065722.1026-1-javen_xu%40realsil.com.cn