linux/net/hsr/hsr_device.c

504 lines
12 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
*
* This file contains device methods for creating, using and destroying
* virtual HSR devices.
*/
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/pkt_sched.h>
#include "hsr_device.h"
#include "hsr_slave.h"
#include "hsr_framereg.h"
#include "hsr_main.h"
#include "hsr_forward.h"
static bool is_admin_up(struct net_device *dev)
{
return dev && (dev->flags & IFF_UP);
}
static bool is_slave_up(struct net_device *dev)
{
return dev && is_admin_up(dev) && netif_oper_up(dev);
}
static void __hsr_set_operstate(struct net_device *dev, int transition)
{
write_lock_bh(&dev_base_lock);
if (dev->operstate != transition) {
dev->operstate = transition;
write_unlock_bh(&dev_base_lock);
netdev_state_change(dev);
} else {
write_unlock_bh(&dev_base_lock);
}
}
static void hsr_set_operstate(struct hsr_port *master, bool has_carrier)
{
if (!is_admin_up(master->dev)) {
__hsr_set_operstate(master->dev, IF_OPER_DOWN);
return;
}
if (has_carrier)
__hsr_set_operstate(master->dev, IF_OPER_UP);
else
__hsr_set_operstate(master->dev, IF_OPER_LOWERLAYERDOWN);
}
static bool hsr_check_carrier(struct hsr_port *master)
{
struct hsr_port *port;
bool has_carrier;
has_carrier = false;
rcu_read_lock();
hsr_for_each_port(master->hsr, port)
if ((port->type != HSR_PT_MASTER) && is_slave_up(port->dev)) {
has_carrier = true;
break;
}
rcu_read_unlock();
if (has_carrier)
netif_carrier_on(master->dev);
else
netif_carrier_off(master->dev);
return has_carrier;
}
static void hsr_check_announce(struct net_device *hsr_dev,
unsigned char old_operstate)
{
struct hsr_priv *hsr;
hsr = netdev_priv(hsr_dev);
if ((hsr_dev->operstate == IF_OPER_UP) && (old_operstate != IF_OPER_UP)) {
/* Went up */
hsr->announce_count = 0;
hsr->announce_timer.expires = jiffies +
msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
add_timer(&hsr->announce_timer);
}
if ((hsr_dev->operstate != IF_OPER_UP) && (old_operstate == IF_OPER_UP))
/* Went down */
del_timer(&hsr->announce_timer);
}
void hsr_check_carrier_and_operstate(struct hsr_priv *hsr)
{
struct hsr_port *master;
unsigned char old_operstate;
bool has_carrier;
master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
/* netif_stacked_transfer_operstate() cannot be used here since
* it doesn't set IF_OPER_LOWERLAYERDOWN (?)
*/
old_operstate = master->dev->operstate;
has_carrier = hsr_check_carrier(master);
hsr_set_operstate(master, has_carrier);
hsr_check_announce(master->dev, old_operstate);
}
int hsr_get_max_mtu(struct hsr_priv *hsr)
{
unsigned int mtu_max;
struct hsr_port *port;
mtu_max = ETH_DATA_LEN;
rcu_read_lock();
hsr_for_each_port(hsr, port)
if (port->type != HSR_PT_MASTER)
mtu_max = min(port->dev->mtu, mtu_max);
rcu_read_unlock();
if (mtu_max < HSR_HLEN)
return 0;
return mtu_max - HSR_HLEN;
}
static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
{
struct hsr_priv *hsr;
struct hsr_port *master;
hsr = netdev_priv(dev);
master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
if (new_mtu > hsr_get_max_mtu(hsr)) {
netdev_info(master->dev, "A HSR master's MTU cannot be greater than the smallest MTU of its slaves minus the HSR Tag length (%d octets).\n",
HSR_HLEN);
return -EINVAL;
}
dev->mtu = new_mtu;
return 0;
}
static int hsr_dev_open(struct net_device *dev)
{
struct hsr_priv *hsr;
struct hsr_port *port;
char designation;
hsr = netdev_priv(dev);
designation = '\0';
rcu_read_lock();
hsr_for_each_port(hsr, port) {
if (port->type == HSR_PT_MASTER)
continue;
switch (port->type) {
case HSR_PT_SLAVE_A:
designation = 'A';
break;
case HSR_PT_SLAVE_B:
designation = 'B';
break;
default:
designation = '?';
}
if (!is_slave_up(port->dev))
netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a fully working HSR network\n",
designation, port->dev->name);
}
rcu_read_unlock();
if (designation == '\0')
netdev_warn(dev, "No slave devices configured\n");
return 0;
}
static int hsr_dev_close(struct net_device *dev)
{
/* Nothing to do here. */
return 0;
}
static netdev_features_t hsr_features_recompute(struct hsr_priv *hsr,
netdev_features_t features)
{
netdev_features_t mask;
struct hsr_port *port;
mask = features;
/* Mask out all features that, if supported by one device, should be
* enabled for all devices (see NETIF_F_ONE_FOR_ALL).
*
* Anything that's off in mask will not be enabled - so only things
* that were in features originally, and also is in NETIF_F_ONE_FOR_ALL,
* may become enabled.
*/
features &= ~NETIF_F_ONE_FOR_ALL;
hsr_for_each_port(hsr, port)
features = netdev_increment_features(features,
port->dev->features,
mask);
return features;
}
static netdev_features_t hsr_fix_features(struct net_device *dev,
netdev_features_t features)
{
struct hsr_priv *hsr = netdev_priv(dev);
return hsr_features_recompute(hsr, features);
}
static int hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct hsr_priv *hsr = netdev_priv(dev);
struct hsr_port *master;
master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
skb->dev = master->dev;
hsr_forward_skb(skb, master);
return NETDEV_TX_OK;
}
static const struct header_ops hsr_header_ops = {
.create = eth_header,
.parse = eth_header_parse,
};
/* HSR:2010 supervision frames should be padded so that the whole frame,
* including headers and FCS, is 64 bytes (without VLAN).
*/
static int hsr_pad(int size)
{
const int min_size = ETH_ZLEN - HSR_HLEN - ETH_HLEN;
if (size >= min_size)
return size;
return min_size;
}
static void send_hsr_supervision_frame(struct hsr_port *master, u8 type)
{
struct sk_buff *skb;
int hlen, tlen;
struct hsr_sup_tag *hsr_stag;
struct hsr_sup_payload *hsr_sp;
unsigned long irqflags;
hlen = LL_RESERVED_SPACE(master->dev);
tlen = master->dev->needed_tailroom;
skb = alloc_skb(hsr_pad(sizeof(struct hsr_sup_payload)) + hlen + tlen,
GFP_ATOMIC);
if (skb == NULL)
return;
skb_reserve(skb, hlen);
skb->dev = master->dev;
skb->protocol = htons(ETH_P_PRP);
skb->priority = TC_PRIO_CONTROL;
if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
master->hsr->sup_multicast_addr,
skb->dev->dev_addr, skb->len) <= 0)
goto out;
skb_reset_mac_header(skb);
hsr_stag = (typeof(hsr_stag)) skb_put(skb, sizeof(*hsr_stag));
set_hsr_stag_path(hsr_stag, 0xf);
set_hsr_stag_HSR_Ver(hsr_stag, 0);
spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
hsr_stag->sequence_nr = htons(master->hsr->sequence_nr);
master->hsr->sequence_nr++;
spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
hsr_stag->HSR_TLV_Type = type;
hsr_stag->HSR_TLV_Length = 12;
/* Payload: MacAddressA */
hsr_sp = (typeof(hsr_sp)) skb_put(skb, sizeof(*hsr_sp));
ether_addr_copy(hsr_sp->MacAddressA, master->dev->dev_addr);
hsr_forward_skb(skb, master);
return;
out:
WARN_ON_ONCE("HSR: Could not send supervision frame\n");
kfree_skb(skb);
}
/* Announce (supervision frame) timer function
*/
static void hsr_announce(unsigned long data)
{
struct hsr_priv *hsr;
struct hsr_port *master;
hsr = (struct hsr_priv *) data;
rcu_read_lock();
master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
if (hsr->announce_count < 3) {
send_hsr_supervision_frame(master, HSR_TLV_ANNOUNCE);
hsr->announce_count++;
} else {
send_hsr_supervision_frame(master, HSR_TLV_LIFE_CHECK);
}
if (hsr->announce_count < 3)
hsr->announce_timer.expires = jiffies +
msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
else
hsr->announce_timer.expires = jiffies +
msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
if (is_admin_up(master->dev))
add_timer(&hsr->announce_timer);
rcu_read_unlock();
}
/* According to comments in the declaration of struct net_device, this function
* is "Called from unregister, can be used to call free_netdev". Ok then...
*/
static void hsr_dev_destroy(struct net_device *hsr_dev)
{
struct hsr_priv *hsr;
struct hsr_port *port;
hsr = netdev_priv(hsr_dev);
rtnl_lock();
hsr_for_each_port(hsr, port)
hsr_del_port(port);
rtnl_unlock();
del_timer_sync(&hsr->prune_timer);
del_timer_sync(&hsr->announce_timer);
synchronize_rcu();
free_netdev(hsr_dev);
}
static const struct net_device_ops hsr_device_ops = {
.ndo_change_mtu = hsr_dev_change_mtu,
.ndo_open = hsr_dev_open,
.ndo_stop = hsr_dev_close,
.ndo_start_xmit = hsr_dev_xmit,
.ndo_fix_features = hsr_fix_features,
};
static struct device_type hsr_type = {
.name = "hsr",
};
void hsr_dev_setup(struct net_device *dev)
{
random_ether_addr(dev->dev_addr);
ether_setup(dev);
dev->header_ops = &hsr_header_ops;
dev->netdev_ops = &hsr_device_ops;
SET_NETDEV_DEVTYPE(dev, &hsr_type);
dev->priv_flags |= IFF_NO_QUEUE;
dev->destructor = hsr_dev_destroy;
dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
NETIF_F_HW_VLAN_CTAG_TX;
dev->features = dev->hw_features;
/* Prevent recursive tx locking */
dev->features |= NETIF_F_LLTX;
/* VLAN on top of HSR needs testing and probably some work on
* hsr_header_create() etc.
*/
dev->features |= NETIF_F_VLAN_CHALLENGED;
/* Not sure about this. Taken from bridge code. netdev_features.h says
* it means "Does not change network namespaces".
*/
dev->features |= NETIF_F_NETNS_LOCAL;
}
/* Return true if dev is a HSR master; return false otherwise.
*/
inline bool is_hsr_master(struct net_device *dev)
{
return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
}
/* Default multicast address for HSR Supervision frames */
static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
};
int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
unsigned char multicast_spec)
{
struct hsr_priv *hsr;
struct hsr_port *port;
int res;
hsr = netdev_priv(hsr_dev);
INIT_LIST_HEAD(&hsr->ports);
INIT_LIST_HEAD(&hsr->node_db);
INIT_LIST_HEAD(&hsr->self_node_db);
ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);
/* Make sure we recognize frames from ourselves in hsr_rcv() */
res = hsr_create_self_node(&hsr->self_node_db, hsr_dev->dev_addr,
slave[1]->dev_addr);
if (res < 0)
return res;
spin_lock_init(&hsr->seqnr_lock);
/* Overflow soon to find bugs easier: */
hsr->sequence_nr = HSR_SEQNR_START;
init_timer(&hsr->announce_timer);
hsr->announce_timer.function = hsr_announce;
hsr->announce_timer.data = (unsigned long) hsr;
init_timer(&hsr->prune_timer);
hsr->prune_timer.function = hsr_prune_nodes;
hsr->prune_timer.data = (unsigned long) hsr;
ether_addr_copy(hsr->sup_multicast_addr, def_multicast_addr);
hsr->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
/* FIXME: should I modify the value of these?
*
* - hsr_dev->flags - i.e.
* IFF_MASTER/SLAVE?
* - hsr_dev->priv_flags - i.e.
* IFF_EBRIDGE?
* IFF_TX_SKB_SHARING?
* IFF_HSR_MASTER/SLAVE?
*/
/* Make sure the 1st call to netif_carrier_on() gets through */
netif_carrier_off(hsr_dev);
res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER);
if (res)
return res;
res = register_netdevice(hsr_dev);
if (res)
goto fail;
res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A);
if (res)
goto fail;
res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B);
if (res)
goto fail;
hsr->prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
add_timer(&hsr->prune_timer);
return 0;
fail:
hsr_for_each_port(hsr, port)
hsr_del_port(port);
return res;
}