net: dsa: reduce number of protocol hooks

DSA is currently registering one packet_type function per EtherType it
needs to intercept in the receive path of a DSA-enabled Ethernet device.
Right now we have three of them: trailer, DSA and eDSA, and there might
be more in the future, this will not scale to the addition of new
protocols.

This patch proceeds with adding a new layer of abstraction and two new
functions:

dsa_switch_rcv() which will dispatch into the tag-protocol specific
receive function implemented by net/dsa/tag_*.c

dsa_slave_xmit() which will dispatch into the tag-protocol specific
transmit function implemented by net/dsa/tag_*.c

When we do create the per-port slave network devices, we iterate over
the switch protocol to assign the DSA-specific receive and transmit
operations.

A new fake ethertype value is used: ETH_P_XDSA to illustrate the fact
that this is no longer going to look like ETH_P_DSA or ETH_P_TRAILER
like it used to be.

This allows us to greatly simplify the check in eth_type_trans() and
always override the skb->protocol with ETH_P_XDSA for Ethernet switches
tagged protocol, while also reducing the number repetitive slave
netdevice_ops assignments.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Florian Fainelli 2014-08-27 17:04:46 -07:00 committed by David S. Miller
parent 8663dc2002
commit 3e8a72d1da
10 changed files with 68 additions and 105 deletions

View file

@ -1781,24 +1781,13 @@ void dev_net_set(struct net_device *dev, struct net *net)
#endif
}
static inline bool netdev_uses_dsa_tags(struct net_device *dev)
static inline bool netdev_uses_dsa(struct net_device *dev)
{
#ifdef CONFIG_NET_DSA_TAG_DSA
if (dev->dsa_ptr != NULL)
return dsa_uses_dsa_tags(dev->dsa_ptr);
#ifdef CONFIG_NET_DSA
return dev->dsa_ptr != NULL;
#else
return false;
#endif
return 0;
}
static inline bool netdev_uses_trailer_tags(struct net_device *dev)
{
#ifdef CONFIG_NET_DSA_TAG_TRAILER
if (dev->dsa_ptr != NULL)
return dsa_uses_trailer_tags(dev->dsa_ptr);
#endif
return 0;
}
/**
@ -1933,6 +1922,13 @@ struct udp_offload {
struct offload_callbacks callbacks;
};
struct dsa_device_ops {
netdev_tx_t (*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);
};
/* often modified stats are per cpu, other are shared (netdev->stats) */
struct pcpu_sw_netstats {
u64 rx_packets;

View file

@ -59,6 +59,8 @@ struct dsa_platform_data {
struct dsa_chip_data *chip;
};
struct dsa_device_ops;
struct dsa_switch_tree {
/*
* Configuration data for the platform device that owns
@ -71,6 +73,7 @@ struct dsa_switch_tree {
* protocol to use.
*/
struct net_device *master_netdev;
const struct dsa_device_ops *ops;
__be16 tag_protocol;
/*
@ -186,21 +189,4 @@ static inline void *ds_to_priv(struct dsa_switch *ds)
return (void *)(ds + 1);
}
/*
* The original DSA tag format and some other tag formats have no
* ethertype, which means that we need to add a little hack to the
* networking receive path to make sure that received frames get
* the right ->protocol assigned to them when one of those tag
* formats is in use.
*/
static inline bool dsa_uses_dsa_tags(struct dsa_switch_tree *dst)
{
return !!(dst->tag_protocol == htons(ETH_P_DSA));
}
static inline bool dsa_uses_trailer_tags(struct dsa_switch_tree *dst)
{
return !!(dst->tag_protocol == htons(ETH_P_TRAILER));
}
#endif

View file

@ -128,6 +128,7 @@
#define ETH_P_PHONET 0x00F5 /* Nokia Phonet frames */
#define ETH_P_IEEE802154 0x00F6 /* IEEE802.15.4 frame */
#define ETH_P_CAIF 0x00F7 /* ST-Ericsson CAIF protocol */
#define ETH_P_XDSA 0x00F8 /* Multiplexed DSA protocol */
/*
* This is an Ethernet frame header.

View file

@ -608,6 +608,24 @@ static void dsa_shutdown(struct platform_device *pdev)
{
}
static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
struct dsa_switch_tree *dst = dev->dsa_ptr;
if (unlikely(dst == NULL)) {
kfree_skb(skb);
return 0;
}
return dst->ops->rcv(skb, dev, pt, orig_dev);
}
struct packet_type dsa_pack_type __read_mostly = {
.type = cpu_to_be16(ETH_P_XDSA),
.func = dsa_switch_rcv,
};
static const struct of_device_id dsa_of_match_table[] = {
{ .compatible = "marvell,dsa", },
{}
@ -633,30 +651,15 @@ static int __init dsa_init_module(void)
if (rc)
return rc;
#ifdef CONFIG_NET_DSA_TAG_DSA
dev_add_pack(&dsa_packet_type);
#endif
#ifdef CONFIG_NET_DSA_TAG_EDSA
dev_add_pack(&edsa_packet_type);
#endif
#ifdef CONFIG_NET_DSA_TAG_TRAILER
dev_add_pack(&trailer_packet_type);
#endif
dev_add_pack(&dsa_pack_type);
return 0;
}
module_init(dsa_init_module);
static void __exit dsa_cleanup_module(void)
{
#ifdef CONFIG_NET_DSA_TAG_TRAILER
dev_remove_pack(&trailer_packet_type);
#endif
#ifdef CONFIG_NET_DSA_TAG_EDSA
dev_remove_pack(&edsa_packet_type);
#endif
#ifdef CONFIG_NET_DSA_TAG_DSA
dev_remove_pack(&dsa_packet_type);
#endif
dev_remove_pack(&dsa_pack_type);
platform_driver_unregister(&dsa_driver);
}
module_exit(dsa_cleanup_module);

View file

@ -45,16 +45,13 @@ struct net_device *dsa_slave_create(struct dsa_switch *ds,
int port, char *name);
/* tag_dsa.c */
netdev_tx_t dsa_xmit(struct sk_buff *skb, struct net_device *dev);
extern struct packet_type dsa_packet_type;
extern const struct dsa_device_ops dsa_netdev_ops;
/* tag_edsa.c */
netdev_tx_t edsa_xmit(struct sk_buff *skb, struct net_device *dev);
extern struct packet_type edsa_packet_type;
extern const struct dsa_device_ops edsa_netdev_ops;
/* tag_trailer.c */
netdev_tx_t trailer_xmit(struct sk_buff *skb, struct net_device *dev);
extern struct packet_type trailer_packet_type;
extern const struct dsa_device_ops trailer_netdev_ops;
#endif

View file

@ -171,6 +171,14 @@ static int dsa_slave_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
return -EOPNOTSUPP;
}
static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct dsa_slave_priv *p = netdev_priv(dev);
struct dsa_switch_tree *dst = p->parent->dst;
return dst->ops->xmit(skb, dev);
}
/* ethtool operations *******************************************************/
static int
@ -293,42 +301,16 @@ static const struct ethtool_ops dsa_slave_ethtool_ops = {
.get_sset_count = dsa_slave_get_sset_count,
};
#ifdef CONFIG_NET_DSA_TAG_DSA
static const struct net_device_ops dsa_netdev_ops = {
static const struct net_device_ops dsa_slave_netdev_ops = {
.ndo_init = dsa_slave_init,
.ndo_open = dsa_slave_open,
.ndo_stop = dsa_slave_close,
.ndo_start_xmit = dsa_xmit,
.ndo_start_xmit = dsa_slave_xmit,
.ndo_change_rx_flags = dsa_slave_change_rx_flags,
.ndo_set_rx_mode = dsa_slave_set_rx_mode,
.ndo_set_mac_address = dsa_slave_set_mac_address,
.ndo_do_ioctl = dsa_slave_ioctl,
};
#endif
#ifdef CONFIG_NET_DSA_TAG_EDSA
static const struct net_device_ops edsa_netdev_ops = {
.ndo_init = dsa_slave_init,
.ndo_open = dsa_slave_open,
.ndo_stop = dsa_slave_close,
.ndo_start_xmit = edsa_xmit,
.ndo_change_rx_flags = dsa_slave_change_rx_flags,
.ndo_set_rx_mode = dsa_slave_set_rx_mode,
.ndo_set_mac_address = dsa_slave_set_mac_address,
.ndo_do_ioctl = dsa_slave_ioctl,
};
#endif
#ifdef CONFIG_NET_DSA_TAG_TRAILER
static const struct net_device_ops trailer_netdev_ops = {
.ndo_init = dsa_slave_init,
.ndo_open = dsa_slave_open,
.ndo_stop = dsa_slave_close,
.ndo_start_xmit = trailer_xmit,
.ndo_change_rx_flags = dsa_slave_change_rx_flags,
.ndo_set_rx_mode = dsa_slave_set_rx_mode,
.ndo_set_mac_address = dsa_slave_set_mac_address,
.ndo_do_ioctl = dsa_slave_ioctl,
};
#endif
/* slave device setup *******************************************************/
struct net_device *
@ -349,21 +331,22 @@ dsa_slave_create(struct dsa_switch *ds, struct device *parent,
slave_dev->ethtool_ops = &dsa_slave_ethtool_ops;
eth_hw_addr_inherit(slave_dev, master);
slave_dev->tx_queue_len = 0;
slave_dev->netdev_ops = &dsa_slave_netdev_ops;
switch (ds->dst->tag_protocol) {
#ifdef CONFIG_NET_DSA_TAG_DSA
case htons(ETH_P_DSA):
slave_dev->netdev_ops = &dsa_netdev_ops;
ds->dst->ops = &dsa_netdev_ops;
break;
#endif
#ifdef CONFIG_NET_DSA_TAG_EDSA
case htons(ETH_P_EDSA):
slave_dev->netdev_ops = &edsa_netdev_ops;
ds->dst->ops = &edsa_netdev_ops;
break;
#endif
#ifdef CONFIG_NET_DSA_TAG_TRAILER
case htons(ETH_P_TRAILER):
slave_dev->netdev_ops = &trailer_netdev_ops;
ds->dst->ops = &trailer_netdev_ops;
break;
#endif
default:

View file

@ -16,7 +16,7 @@
#define DSA_HLEN 4
netdev_tx_t dsa_xmit(struct sk_buff *skb, struct net_device *dev)
static netdev_tx_t dsa_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct dsa_slave_priv *p = netdev_priv(dev);
u8 *dsa_header;
@ -186,7 +186,7 @@ out:
return 0;
}
struct packet_type dsa_packet_type __read_mostly = {
.type = cpu_to_be16(ETH_P_DSA),
.func = dsa_rcv,
const struct dsa_device_ops dsa_netdev_ops = {
.xmit = dsa_xmit,
.rcv = dsa_rcv,
};

View file

@ -17,7 +17,7 @@
#define DSA_HLEN 4
#define EDSA_HLEN 8
netdev_tx_t edsa_xmit(struct sk_buff *skb, struct net_device *dev)
static netdev_tx_t edsa_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct dsa_slave_priv *p = netdev_priv(dev);
u8 *edsa_header;
@ -205,7 +205,7 @@ out:
return 0;
}
struct packet_type edsa_packet_type __read_mostly = {
.type = cpu_to_be16(ETH_P_EDSA),
.func = edsa_rcv,
const struct dsa_device_ops edsa_netdev_ops = {
.xmit = edsa_xmit,
.rcv = edsa_rcv,
};

View file

@ -14,7 +14,7 @@
#include <linux/slab.h>
#include "dsa_priv.h"
netdev_tx_t trailer_xmit(struct sk_buff *skb, struct net_device *dev)
static netdev_tx_t trailer_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct dsa_slave_priv *p = netdev_priv(dev);
struct sk_buff *nskb;
@ -114,7 +114,7 @@ out:
return 0;
}
struct packet_type trailer_packet_type __read_mostly = {
.type = cpu_to_be16(ETH_P_TRAILER),
.func = trailer_rcv,
const struct dsa_device_ops trailer_netdev_ops = {
.xmit = trailer_xmit,
.rcv = trailer_rcv,
};

View file

@ -181,11 +181,8 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
* variants has been configured on the receiving interface,
* and if so, set skb->protocol without looking at the packet.
*/
if (unlikely(netdev_uses_dsa_tags(dev)))
return htons(ETH_P_DSA);
if (unlikely(netdev_uses_trailer_tags(dev)))
return htons(ETH_P_TRAILER);
if (unlikely(netdev_uses_dsa(dev)))
return htons(ETH_P_XDSA);
if (likely(ntohs(eth->h_proto) >= ETH_P_802_3_MIN))
return eth->h_proto;