linux/net/hsr/hsr_slave.c
Arvid Brodin f266a683a4 net/hsr: Better frame dispatch
This patch removes the separate paths for frames coming from the outside, and
frames sent from the HSR device, and instead makes all frames go through
hsr_forward_skb() in hsr_forward.c. This greatly improves code readability and
also opens up the possibility for future support of the HSR Interlink device
that is the basis for HSR RedBoxes and HSR QuadBoxes, as well as VLAN
compatibility.

Other improvements:
* A reduction in the number of times an skb is copied on machines without
  HAVE_EFFICIENT_UNALIGNED_ACCESS, which improves throughput somewhat.
* Headers are now created using the standard eth_header(), and using the
  standard hard_header_len.
* Each HSR slave now gets its own private skb, so slave-specific fields can be
  correctly set.

Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-08 11:35:31 -07:00

197 lines
4.3 KiB
C

/* Copyright 2011-2014 Autronica Fire and Security AS
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* Author(s):
* 2011-2014 Arvid Brodin, arvid.brodin@alten.se
*/
#include "hsr_slave.h"
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include "hsr_main.h"
#include "hsr_device.h"
#include "hsr_forward.h"
#include "hsr_framereg.h"
static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
{
struct sk_buff *skb = *pskb;
struct hsr_port *port;
if (!skb_mac_header_was_set(skb)) {
WARN_ONCE(1, "%s: skb invalid", __func__);
return RX_HANDLER_PASS;
}
rcu_read_lock(); /* hsr->node_db, hsr->ports */
port = hsr_port_get_rcu(skb->dev);
if (hsr_addr_is_self(port->hsr, eth_hdr(skb)->h_source)) {
/* Directly kill frames sent by ourselves */
kfree_skb(skb);
goto finish_consume;
}
if (eth_hdr(skb)->h_proto != htons(ETH_P_PRP))
goto finish_pass;
skb_push(skb, ETH_HLEN);
hsr_forward_skb(skb, port);
finish_consume:
rcu_read_unlock(); /* hsr->node_db, hsr->ports */
return RX_HANDLER_CONSUMED;
finish_pass:
rcu_read_unlock(); /* hsr->node_db, hsr->ports */
return RX_HANDLER_PASS;
}
bool hsr_port_exists(const struct net_device *dev)
{
return rcu_access_pointer(dev->rx_handler) == hsr_handle_frame;
}
static int hsr_check_dev_ok(struct net_device *dev)
{
/* Don't allow HSR on non-ethernet like devices */
if ((dev->flags & IFF_LOOPBACK) || (dev->type != ARPHRD_ETHER) ||
(dev->addr_len != ETH_ALEN)) {
netdev_info(dev, "Cannot use loopback or non-ethernet device as HSR slave.\n");
return -EINVAL;
}
/* Don't allow enslaving hsr devices */
if (is_hsr_master(dev)) {
netdev_info(dev, "Cannot create trees of HSR devices.\n");
return -EINVAL;
}
if (hsr_port_exists(dev)) {
netdev_info(dev, "This device is already a HSR slave.\n");
return -EINVAL;
}
if (dev->priv_flags & IFF_802_1Q_VLAN) {
netdev_info(dev, "HSR on top of VLAN is not yet supported in this driver.\n");
return -EINVAL;
}
if (dev->priv_flags & IFF_DONT_BRIDGE) {
netdev_info(dev, "This device does not support bridging.\n");
return -EOPNOTSUPP;
}
/* HSR over bonded devices has not been tested, but I'm not sure it
* won't work...
*/
return 0;
}
/* Setup device to be added to the HSR bridge. */
static int hsr_portdev_setup(struct net_device *dev, struct hsr_port *port)
{
int res;
dev_hold(dev);
res = dev_set_promiscuity(dev, 1);
if (res)
goto fail_promiscuity;
/* FIXME:
* What does net device "adjacency" mean? Should we do
* res = netdev_master_upper_dev_link(port->dev, port->hsr->dev); ?
*/
res = netdev_rx_handler_register(dev, hsr_handle_frame, port);
if (res)
goto fail_rx_handler;
dev_disable_lro(dev);
return 0;
fail_rx_handler:
dev_set_promiscuity(dev, -1);
fail_promiscuity:
dev_put(dev);
return res;
}
int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev,
enum hsr_port_type type)
{
struct hsr_port *port, *master;
int res;
if (type != HSR_PT_MASTER) {
res = hsr_check_dev_ok(dev);
if (res)
return res;
}
port = hsr_port_get_hsr(hsr, type);
if (port != NULL)
return -EBUSY; /* This port already exists */
port = kzalloc(sizeof(*port), GFP_KERNEL);
if (port == NULL)
return -ENOMEM;
if (type != HSR_PT_MASTER) {
res = hsr_portdev_setup(dev, port);
if (res)
goto fail_dev_setup;
}
port->hsr = hsr;
port->dev = dev;
port->type = type;
list_add_tail_rcu(&port->port_list, &hsr->ports);
synchronize_rcu();
master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
netdev_update_features(master->dev);
dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
return 0;
fail_dev_setup:
kfree(port);
return res;
}
void hsr_del_port(struct hsr_port *port)
{
struct hsr_priv *hsr;
struct hsr_port *master;
hsr = port->hsr;
master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
list_del_rcu(&port->port_list);
if (port != master) {
netdev_update_features(master->dev);
dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
netdev_rx_handler_unregister(port->dev);
dev_set_promiscuity(port->dev, -1);
}
/* FIXME?
* netdev_upper_dev_unlink(port->dev, port->hsr->dev);
*/
synchronize_rcu();
dev_put(port->dev);
}