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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>
wifi-calibration
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
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
include/linux/netdevice.h
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;

20
include/net/dsa.h
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

1
include/uapi/linux/if_ether.h
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.

39
net/dsa/dsa.c
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);

9
net/dsa/dsa_priv.h
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

45
net/dsa/slave.c
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:

8
net/dsa/tag_dsa.c
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,
};

8
net/dsa/tag_edsa.c
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,
};

8
net/dsa/tag_trailer.c
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,
};

7
net/ethernet/eth.c
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;