[PATCH net-next v2 0/4] net: GENET, SYSTEMPORT and DSA netconsole

[PATCH net-next v2 0/4] net: GENET, SYSTEMPORT and DSA netconsole

[Florian Fainelli]

Hi all,

This patch series adds support for netconsole in the GENET, SYSTEMPORT and DSA
drivers.

A small refactoring to the DSA transmit path is required to avoid duplicating
the dsa_netpoll_send_skb() into each and every tagging protocol supported.

Testing on e.g: mv643xx_eth and/or e1000e would be much appreciated!

Changes in v2:

- properly disable/enable interrupts in GENET and SYSTEMPORT

- pass the reallocated SKB back to dsa_slave_xmit() in case a tag protocol had to
  alter the original SKB

Florian Fainelli (4):
  net: bcmgenet: Add netconsole support
  net: systemport: Add netconsole support
  net: dsa: Refactor transmit path to eliminate duplication
  net: dsa: Add netconsole support

 drivers/net/ethernet/broadcom/bcmsysport.c     | 18 +++++
 drivers/net/ethernet/broadcom/genet/bcmgenet.c | 20 ++++++
 net/dsa/dsa_priv.h                             |  8 ++-
 net/dsa/slave.c                                | 94 +++++++++++++++++++++++---
 net/dsa/tag_brcm.c                             | 15 +---
 net/dsa/tag_dsa.c                              | 12 +---
 net/dsa/tag_edsa.c                             | 12 +---
 net/dsa/tag_trailer.c                          | 12 +---
 8 files changed, 142 insertions(+), 49 deletions(-)

-- 
2.1.0

[PATCH net-next v2 1/4] net: bcmgenet: Add netconsole support

[Florian Fainelli]

Implement a poll controller for netconsole which invokes both of our
interrupt handlers for the different RX/TX queues.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
Changes in v2:

- properly pair the interrupt handler with disable/enable_irq pairs
- remove the call to bcmgenet_tx_reclaim, this is done by the handler

 drivers/net/ethernet/broadcom/genet/bcmgenet.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index c6f2d396edf0..eb080ef8ee97 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -2388,6 +2388,23 @@ static irqreturn_t bcmgenet_wol_isr(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void bcmgenet_poll_controller(struct net_device *dev)
+{
+	struct bcmgenet_priv *priv = netdev_priv(dev);
+
+	/* Invoke the main RX/TX interrupt handler */
+	disable_irq(priv->irq0);
+	bcmgenet_isr0(priv->irq0, priv);
+	enable_irq(priv->irq0);
+
+	/* And the interrupt handler for RX/TX priority queues */
+	disable_irq(priv->irq1);
+	bcmgenet_isr1(priv->irq1, priv);
+	enable_irq(priv->irq1);
+}
+#endif
+
 static void bcmgenet_umac_reset(struct bcmgenet_priv *priv)
 {
 	u32 reg;
@@ -2939,6 +2956,9 @@ static const struct net_device_ops bcmgenet_netdev_ops = {
 	.ndo_set_mac_address	= bcmgenet_set_mac_addr,
 	.ndo_do_ioctl		= bcmgenet_ioctl,
 	.ndo_set_features	= bcmgenet_set_features,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller	= bcmgenet_poll_controller,
+#endif
 };
 
 /* Array of GENET hardware parameters/characteristics */
-- 
2.1.0

[PATCH net-next v2 2/4] net: systemport: Add netconsole support

[Florian Fainelli]

Implement a poll controller for netconsole which invokes the RX
interrupt handler to poll for incoming packets, and cleans up all TX
queues by invoking the TX interrupt handler.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
Changes in v2:

- properly pair the interrupt handler calls with disable/enable_irq
- remove the call to bcm_sysport_tx_reclaim, handler does this

 drivers/net/ethernet/broadcom/bcmsysport.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index 4566cdf0bc39..b9a5a97ed4dd 100644
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -933,6 +933,21 @@ static irqreturn_t bcm_sysport_wol_isr(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void bcm_sysport_poll_controller(struct net_device *dev)
+{
+	struct bcm_sysport_priv *priv = netdev_priv(dev);
+
+	disable_irq(priv->irq0);
+	bcm_sysport_rx_isr(priv->irq0, priv);
+	enable_irq(priv->irq0);
+
+	disable_irq(priv->irq1);
+	bcm_sysport_tx_isr(priv->irq1, priv);
+	enable_irq(priv->irq1);
+}
+#endif
+
 static struct sk_buff *bcm_sysport_insert_tsb(struct sk_buff *skb,
 					      struct net_device *dev)
 {
@@ -1723,6 +1738,9 @@ static const struct net_device_ops bcm_sysport_netdev_ops = {
 	.ndo_set_features	= bcm_sysport_set_features,
 	.ndo_set_rx_mode	= bcm_sysport_set_rx_mode,
 	.ndo_set_mac_address	= bcm_sysport_change_mac,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller	= bcm_sysport_poll_controller,
+#endif
 };
 
 #define REV_FMT	"v%2x.%02x"
-- 
2.1.0

[PATCH net-next v2 3/4] net: dsa: Refactor transmit path to eliminate duplication

[Florian Fainelli]

All tagging protocols do the same thing: increment device statistics,
make room for the tag to be inserted, create the tag, invoke the parent
network device transmit function.

In order to prepare for adding netpoll support, which requires the tag
creation, but not using the parent network device transmit function, do
some little refactoring which eliminates duplication between the 4
tagging protocols supported.

We need to return a sk_buff pointer back to the caller because the tag
specific transmit function may have to reallocate the original skb (e.g:
tag_trailer.c) and this is the one we should be transmitting, not the
original sk_buff we were passed.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
Changes in v2:

- take a sk_buff pointer back from the tag's xmit function in case the
  SKB was re-allocated/altered from the original one

 net/dsa/dsa_priv.h    |  4 ++--
 net/dsa/slave.c       | 27 +++++++++++++++++++--------
 net/dsa/tag_brcm.c    | 15 +++------------
 net/dsa/tag_dsa.c     | 12 +++---------
 net/dsa/tag_edsa.c    | 12 +++---------
 net/dsa/tag_trailer.c | 12 +++---------
 6 files changed, 33 insertions(+), 49 deletions(-)

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index d5f1f9b862ea..eeade901e67a 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -15,7 +15,7 @@
 #include <linux/netdevice.h>
 
 struct dsa_device_ops {
-	netdev_tx_t (*xmit)(struct sk_buff *skb, struct net_device *dev);
+	struct sk_buff *(*xmit)(struct sk_buff *skb, struct net_device *dev);
 	int (*rcv)(struct sk_buff *skb, struct net_device *dev,
 		   struct packet_type *pt, struct net_device *orig_dev);
 };
@@ -26,7 +26,7 @@ struct dsa_slave_priv {
 	 * switch port.
 	 */
 	struct net_device	*dev;
-	netdev_tx_t		(*xmit)(struct sk_buff *skb,
+	struct sk_buff *	(*xmit)(struct sk_buff *skb,
 					struct net_device *dev);
 
 	/*
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 0917123790ea..5fc87ee53905 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -421,21 +421,32 @@ static int dsa_slave_port_attr_get(struct net_device *dev,
 static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct sk_buff *nskb;
 
-	return p->xmit(skb, dev);
-}
+	dev->stats.tx_packets++;
+	dev->stats.tx_bytes += skb->len;
 
-static netdev_tx_t dsa_slave_notag_xmit(struct sk_buff *skb,
-					struct net_device *dev)
-{
-	struct dsa_slave_priv *p = netdev_priv(dev);
+	/* Transmit function may have to reallocate the original SKB */
+	nskb = p->xmit(skb, dev);
+	if (!nskb)
+		return NETDEV_TX_OK;
 
-	skb->dev = p->parent->dst->master_netdev;
-	dev_queue_xmit(skb);
+	/* Queue the SKB for transmission on the parent interface, but
+	 * do not modify its EtherType
+	 */
+	nskb->dev = p->parent->dst->master_netdev;
+	dev_queue_xmit(nskb);
 
 	return NETDEV_TX_OK;
 }
 
+static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
+					    struct net_device *dev)
+{
+	/* Just return the original SKB */
+	return skb;
+}
+
 
 /* ethtool operations *******************************************************/
 static int
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 83d3572cdb20..e2aadb73111d 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -58,14 +58,11 @@
 #define BRCM_EG_TC_MASK		0x7
 #define BRCM_EG_PID_MASK	0x1f
 
-static netdev_tx_t brcm_tag_xmit(struct sk_buff *skb, struct net_device *dev)
+static struct sk_buff *brcm_tag_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	u8 *brcm_tag;
 
-	dev->stats.tx_packets++;
-	dev->stats.tx_bytes += skb->len;
-
 	if (skb_cow_head(skb, BRCM_TAG_LEN) < 0)
 		goto out_free;
 
@@ -87,17 +84,11 @@ static netdev_tx_t brcm_tag_xmit(struct sk_buff *skb, struct net_device *dev)
 		brcm_tag[2] = BRCM_IG_DSTMAP2_MASK;
 	brcm_tag[3] = (1 << p->port) & BRCM_IG_DSTMAP1_MASK;
 
-	/* Queue the SKB for transmission on the parent interface, but
-	 * do not modify its EtherType
-	 */
-	skb->dev = p->parent->dst->master_netdev;
-	dev_queue_xmit(skb);
-
-	return NETDEV_TX_OK;
+	return skb;
 
 out_free:
 	kfree_skb(skb);
-	return NETDEV_TX_OK;
+	return NULL;
 }
 
 static int brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev,
diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
index 2dab27063273..aa780e4ac0bd 100644
--- a/net/dsa/tag_dsa.c
+++ b/net/dsa/tag_dsa.c
@@ -15,14 +15,11 @@
 
 #define DSA_HLEN	4
 
-static netdev_tx_t dsa_xmit(struct sk_buff *skb, struct net_device *dev)
+static struct sk_buff *dsa_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	u8 *dsa_header;
 
-	dev->stats.tx_packets++;
-	dev->stats.tx_bytes += skb->len;
-
 	/*
 	 * Convert the outermost 802.1q tag to a DSA tag for tagged
 	 * packets, or insert a DSA tag between the addresses and
@@ -63,14 +60,11 @@ static netdev_tx_t dsa_xmit(struct sk_buff *skb, struct net_device *dev)
 		dsa_header[3] = 0x00;
 	}
 
-	skb->dev = p->parent->dst->master_netdev;
-	dev_queue_xmit(skb);
-
-	return NETDEV_TX_OK;
+	return skb;
 
 out_free:
 	kfree_skb(skb);
-	return NETDEV_TX_OK;
+	return NULL;
 }
 
 static int dsa_rcv(struct sk_buff *skb, struct net_device *dev,
diff --git a/net/dsa/tag_edsa.c b/net/dsa/tag_edsa.c
index 9aeda596f7ec..2288c8098c42 100644
--- a/net/dsa/tag_edsa.c
+++ b/net/dsa/tag_edsa.c
@@ -16,14 +16,11 @@
 #define DSA_HLEN	4
 #define EDSA_HLEN	8
 
-static netdev_tx_t edsa_xmit(struct sk_buff *skb, struct net_device *dev)
+static struct sk_buff *edsa_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	u8 *edsa_header;
 
-	dev->stats.tx_packets++;
-	dev->stats.tx_bytes += skb->len;
-
 	/*
 	 * Convert the outermost 802.1q tag to a DSA tag and prepend
 	 * a DSA ethertype field is the packet is tagged, or insert
@@ -76,14 +73,11 @@ static netdev_tx_t edsa_xmit(struct sk_buff *skb, struct net_device *dev)
 		edsa_header[7] = 0x00;
 	}
 
-	skb->dev = p->parent->dst->master_netdev;
-	dev_queue_xmit(skb);
-
-	return NETDEV_TX_OK;
+	return skb;
 
 out_free:
 	kfree_skb(skb);
-	return NETDEV_TX_OK;
+	return NULL;
 }
 
 static int edsa_rcv(struct sk_buff *skb, struct net_device *dev,
diff --git a/net/dsa/tag_trailer.c b/net/dsa/tag_trailer.c
index e268f9db8893..d25efc93d8f1 100644
--- a/net/dsa/tag_trailer.c
+++ b/net/dsa/tag_trailer.c
@@ -13,16 +13,13 @@
 #include <linux/slab.h>
 #include "dsa_priv.h"
 
-static netdev_tx_t trailer_xmit(struct sk_buff *skb, struct net_device *dev)
+static struct sk_buff *trailer_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct sk_buff *nskb;
 	int padlen;
 	u8 *trailer;
 
-	dev->stats.tx_packets++;
-	dev->stats.tx_bytes += skb->len;
-
 	/*
 	 * We have to make sure that the trailer ends up as the very
 	 * last 4 bytes of the packet.  This means that we have to pad
@@ -36,7 +33,7 @@ static netdev_tx_t trailer_xmit(struct sk_buff *skb, struct net_device *dev)
 	nskb = alloc_skb(NET_IP_ALIGN + skb->len + padlen + 4, GFP_ATOMIC);
 	if (nskb == NULL) {
 		kfree_skb(skb);
-		return NETDEV_TX_OK;
+		return NULL;
 	}
 	skb_reserve(nskb, NET_IP_ALIGN);
 
@@ -57,10 +54,7 @@ static netdev_tx_t trailer_xmit(struct sk_buff *skb, struct net_device *dev)
 	trailer[2] = 0x10;
 	trailer[3] = 0x00;
 
-	nskb->dev = p->parent->dst->master_netdev;
-	dev_queue_xmit(nskb);
-
-	return NETDEV_TX_OK;
+	return nskb;
 }
 
 static int trailer_rcv(struct sk_buff *skb, struct net_device *dev,
-- 
2.1.0

[PATCH net-next v2 4/4] net: dsa: Add netconsole support

[Florian Fainelli]

Add support for using DSA slave network devices with netconsole, which
requires us to allocate and free custom netpoll instances and invoke the
parent network device poll controller callback.

In order for netconsole to work, we need to construct the DSA tag, but
not queue the skb for transmission on the master network device xmit
function.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 net/dsa/dsa_priv.h |  4 ++++
 net/dsa/slave.c    | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+)

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index eeade901e67a..311796c809af 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -13,6 +13,7 @@
 
 #include <linux/phy.h>
 #include <linux/netdevice.h>
+#include <linux/netpoll.h>
 
 struct dsa_device_ops {
 	struct sk_buff *(*xmit)(struct sk_buff *skb, struct net_device *dev);
@@ -47,6 +48,9 @@ struct dsa_slave_priv {
 	int			old_duplex;
 
 	struct net_device	*bridge_dev;
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	struct netpoll		*netpoll;
+#endif
 };
 
 /* dsa.c */
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 5fc87ee53905..0010c690cc67 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -18,6 +18,7 @@
 #include <net/rtnetlink.h>
 #include <net/switchdev.h>
 #include <linux/if_bridge.h>
+#include <linux/netpoll.h>
 #include "dsa_priv.h"
 
 /* slave mii_bus handling ***************************************************/
@@ -418,6 +419,18 @@ static int dsa_slave_port_attr_get(struct net_device *dev,
 	return 0;
 }
 
+static inline netdev_tx_t dsa_netpoll_send_skb(struct dsa_slave_priv *p,
+					       struct sk_buff *skb)
+{
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	if (p->netpoll)
+		netpoll_send_skb(p->netpoll, skb);
+#else
+	BUG();
+#endif
+	return NETDEV_TX_OK;
+}
+
 static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
@@ -431,6 +444,12 @@ static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev)
 	if (!nskb)
 		return NETDEV_TX_OK;
 
+	/* SKB for netpoll still need to be mangled with the protocol-specific
+	 * tag to be successfully transmitted
+	 */
+	if (unlikely(netpoll_tx_running(dev)))
+		return dsa_netpoll_send_skb(p, nskb);
+
 	/* Queue the SKB for transmission on the parent interface, but
 	 * do not modify its EtherType
 	 */
@@ -676,6 +695,49 @@ static int dsa_slave_get_eee(struct net_device *dev, struct ethtool_eee *e)
 	return ret;
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static int dsa_slave_netpoll_setup(struct net_device *dev,
+				   struct netpoll_info *ni)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_switch *ds = p->parent;
+	struct net_device *master = ds->dst->master_netdev;
+	struct netpoll *netpoll;
+	int err = 0;
+
+	netpoll = kzalloc(sizeof(*netpoll), GFP_KERNEL);
+	if (!netpoll)
+		return -ENOMEM;
+
+	err = __netpoll_setup(netpoll, master);
+	if (err) {
+		kfree(netpoll);
+		goto out;
+	}
+
+	p->netpoll = netpoll;
+out:
+	return err;
+}
+
+static void dsa_slave_netpoll_cleanup(struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct netpoll *netpoll = p->netpoll;
+
+	if (!netpoll)
+		return;
+
+	p->netpoll = NULL;
+
+	__netpoll_free_async(netpoll);
+}
+
+static void dsa_slave_poll_controller(struct net_device *dev)
+{
+}
+#endif
+
 static const struct ethtool_ops dsa_slave_ethtool_ops = {
 	.get_settings		= dsa_slave_get_settings,
 	.set_settings		= dsa_slave_set_settings,
@@ -708,6 +770,11 @@ static const struct net_device_ops dsa_slave_netdev_ops = {
 	.ndo_fdb_dump		= dsa_slave_fdb_dump,
 	.ndo_do_ioctl		= dsa_slave_ioctl,
 	.ndo_get_iflink		= dsa_slave_get_iflink,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_netpoll_setup	= dsa_slave_netpoll_setup,
+	.ndo_netpoll_cleanup	= dsa_slave_netpoll_cleanup,
+	.ndo_poll_controller	= dsa_slave_poll_controller,
+#endif
 };
 
 static const struct switchdev_ops dsa_slave_switchdev_ops = {
-- 
2.1.0

Re: [PATCH net-next v2 0/4] net: GENET, SYSTEMPORT and DSA netconsole

[David Miller]

From: Florian Fainelli <f.fainelli@gmail.com>
Date: Fri, 31 Jul 2015 11:42:53 -0700

> This patch series adds support for netconsole in the GENET, SYSTEMPORT and DSA
> drivers.
> 
> A small refactoring to the DSA transmit path is required to avoid duplicating
> the dsa_netpoll_send_skb() into each and every tagging protocol supported.
> 
> Testing on e.g: mv643xx_eth and/or e1000e would be much appreciated!
> 
> Changes in v2:
> 
> - properly disable/enable interrupts in GENET and SYSTEMPORT
> 
> - pass the reallocated SKB back to dsa_slave_xmit() in case a tag protocol had to
>   alter the original SKB

Looks good, series applied, thanks Florian.