From 4ed70ce9f01c998999e48642a768d9013bee2c4f Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Fri, 31 Jul 2015 11:42:56 -0700 Subject: net: dsa: Refactor transmit path to eliminate duplication 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 Signed-off-by: David S. Miller --- net/dsa/slave.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) (limited to 'net/dsa/slave.c') 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 -- cgit From 04ff53f96a931751a70c2bb3926770900b5fbebe Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Fri, 31 Jul 2015 11:42:57 -0700 Subject: net: dsa: Add netconsole support 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 Signed-off-by: David S. Miller --- net/dsa/slave.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) (limited to 'net/dsa/slave.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 #include #include +#include #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 = { -- cgit