Acked-By: Kirill Korotaev <dev@xxxxx> dlezcano@xxxxxxxxxx wrote: > From: Daniel Lezcano <dlezcano@xxxxxxxxxx> > > Doing this makes loopback.c a better example of how to do a > simple network device, and it removes the special case > single static allocation of a struct net_device, hopefully > making maintenance easier. > > Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> > Signed-off-by: Daniel Lezcano <dlezcano@xxxxxxxxxx> > --- > drivers/net/loopback.c | 63 +++++++++++++++++++++++--------------- > include/linux/netdevice.h | 2 +- > net/core/dst.c | 8 ++-- > net/decnet/dn_dev.c | 4 +- > net/decnet/dn_route.c | 14 ++++---- > net/ipv4/devinet.c | 6 ++-- > net/ipv4/ipconfig.c | 6 ++-- > net/ipv4/ipvs/ip_vs_core.c | 2 +- > net/ipv4/route.c | 18 +++++----- > net/ipv4/xfrm4_policy.c | 2 +- > net/ipv6/addrconf.c | 15 +++++--- > net/ipv6/ip6_input.c | 2 +- > net/ipv6/netfilter/ip6t_REJECT.c | 2 +- > net/ipv6/route.c | 15 +++----- > net/ipv6/xfrm6_policy.c | 2 +- > net/xfrm/xfrm_policy.c | 4 +- > 16 files changed, 89 insertions(+), 76 deletions(-) > > diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c > index 5106c23..3642aff 100644 > --- a/drivers/net/loopback.c > +++ b/drivers/net/loopback.c > @@ -199,44 +199,57 @@ static const struct ethtool_ops loopback_ethtool_ops = { > .get_rx_csum = always_on, > }; > > -/* > - * The loopback device is special. There is only one instance and > - * it is statically allocated. Don't do this for other devices. > - */ > -struct net_device loopback_dev = { > - .name = "lo", > - .get_stats = &get_stats, > - .mtu = (16 * 1024) + 20 + 20 + 12, > - .hard_start_xmit = loopback_xmit, > - .hard_header = eth_header, > - .hard_header_cache = eth_header_cache, > - .header_cache_update = eth_header_cache_update, > - .hard_header_len = ETH_HLEN, /* 14 */ > - .addr_len = ETH_ALEN, /* 6 */ > - .tx_queue_len = 0, > - .type = ARPHRD_LOOPBACK, /* 0x0001*/ > - .rebuild_header = eth_rebuild_header, > - .flags = IFF_LOOPBACK, > - .features = NETIF_F_SG | NETIF_F_FRAGLIST > +static void loopback_setup(struct net_device *dev) > +{ > + dev->get_stats = &get_stats; > + dev->mtu = (16 * 1024) + 20 + 20 + 12; > + dev->hard_start_xmit = loopback_xmit; > + dev->hard_header = eth_header; > + dev->hard_header_cache = eth_header_cache; > + dev->header_cache_update = eth_header_cache_update; > + dev->hard_header_len = ETH_HLEN; /* 14 */ > + dev->addr_len = ETH_ALEN; /* 6 */ > + dev->tx_queue_len = 0; > + dev->type = ARPHRD_LOOPBACK; /* 0x0001*/ > + dev->rebuild_header = eth_rebuild_header; > + dev->flags = IFF_LOOPBACK; > + dev->features = NETIF_F_SG | NETIF_F_FRAGLIST > #ifdef LOOPBACK_TSO > | NETIF_F_TSO > #endif > | NETIF_F_NO_CSUM | NETIF_F_HIGHDMA > - | NETIF_F_LLTX, > - .ethtool_ops = &loopback_ethtool_ops, > -}; > + | NETIF_F_LLTX; > + dev->ethtool_ops = &loopback_ethtool_ops; > +} > > /* Setup and register the loopback device. */ > static int __init loopback_init(void) > { > - int err = register_netdev(&loopback_dev); > + struct net_device *dev; > + int err; > + > + err = -ENOMEM; > + dev = alloc_netdev(0, "lo", loopback_setup); > + if (!dev) > + goto out; > + > + err = register_netdev(dev); > + if (err) > + goto out_free_netdev; > > + err = 0; > + loopback_dev = dev; > + > +out: > if (err) > panic("loopback: Failed to register netdevice: %d\n", err); > - > return err; > +out_free_netdev: > + free_netdev(dev); > + goto out; > }; > > -module_init(loopback_init); > +fs_initcall(loopback_init); > > +struct net_device *loopback_dev; > EXPORT_SYMBOL(loopback_dev); > diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h > index 8d12f02..7cd0641 100644 > --- a/include/linux/netdevice.h > +++ b/include/linux/netdevice.h > @@ -680,7 +680,7 @@ struct packet_type { > #include <linux/interrupt.h> > #include <linux/notifier.h> > > -extern struct net_device loopback_dev; /* The loopback */ > +extern struct net_device *loopback_dev; /* The loopback */ > extern struct list_head dev_base_head; /* All devices */ > extern rwlock_t dev_base_lock; /* Device list lock */ > > diff --git a/net/core/dst.c b/net/core/dst.c > index c6a0587..ad8549e 100644 > --- a/net/core/dst.c > +++ b/net/core/dst.c > @@ -236,13 +236,13 @@ static inline void dst_ifdown(struct dst_entry *dst, struct net_device *dev, > if (!unregister) { > dst->input = dst->output = dst_discard; > } else { > - dst->dev = &loopback_dev; > - dev_hold(&loopback_dev); > + dst->dev = loopback_dev; > + dev_hold(dst->dev); > dev_put(dev); > if (dst->neighbour && dst->neighbour->dev == dev) { > - dst->neighbour->dev = &loopback_dev; > + dst->neighbour->dev = loopback_dev; > dev_put(dev); > - dev_hold(&loopback_dev); > + dev_hold(dst->neighbour->dev); > } > } > } > diff --git a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c > index fa6604f..9fea83e 100644 > --- a/net/decnet/dn_dev.c > +++ b/net/decnet/dn_dev.c > @@ -868,10 +868,10 @@ last_chance: > rv = dn_dev_get_first(dev, addr); > read_unlock(&dev_base_lock); > dev_put(dev); > - if (rv == 0 || dev == &loopback_dev) > + if (rv == 0 || dev == loopback_dev) > return rv; > } > - dev = &loopback_dev; > + dev = loopback_dev; > dev_hold(dev); > goto last_chance; > } > diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c > index a4a6209..8c04ebc 100644 > --- a/net/decnet/dn_route.c > +++ b/net/decnet/dn_route.c > @@ -883,7 +883,7 @@ static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *old > .scope = RT_SCOPE_UNIVERSE, > } }, > .mark = oldflp->mark, > - .iif = loopback_dev.ifindex, > + .iif = loopback_dev->ifindex, > .oif = oldflp->oif }; > struct dn_route *rt = NULL; > struct net_device *dev_out = NULL, *dev; > @@ -900,7 +900,7 @@ static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *old > "dn_route_output_slow: dst=%04x src=%04x mark=%d" > " iif=%d oif=%d\n", dn_ntohs(oldflp->fld_dst), > dn_ntohs(oldflp->fld_src), > - oldflp->mark, loopback_dev.ifindex, oldflp->oif); > + oldflp->mark, loopback_dev->ifindex, oldflp->oif); > > /* If we have an output interface, verify its a DECnet device */ > if (oldflp->oif) { > @@ -953,7 +953,7 @@ source_ok: > err = -EADDRNOTAVAIL; > if (dev_out) > dev_put(dev_out); > - dev_out = &loopback_dev; > + dev_out = loopback_dev; > dev_hold(dev_out); > if (!fl.fld_dst) { > fl.fld_dst = > @@ -962,7 +962,7 @@ source_ok: > if (!fl.fld_dst) > goto out; > } > - fl.oif = loopback_dev.ifindex; > + fl.oif = loopback_dev->ifindex; > res.type = RTN_LOCAL; > goto make_route; > } > @@ -1008,7 +1008,7 @@ source_ok: > if (dev_out) > dev_put(dev_out); > if (dn_dev_islocal(neigh->dev, fl.fld_dst)) { > - dev_out = &loopback_dev; > + dev_out = loopback_dev; > res.type = RTN_LOCAL; > } else { > dev_out = neigh->dev; > @@ -1029,7 +1029,7 @@ source_ok: > /* Possible improvement - check all devices for local addr */ > if (dn_dev_islocal(dev_out, fl.fld_dst)) { > dev_put(dev_out); > - dev_out = &loopback_dev; > + dev_out = loopback_dev; > dev_hold(dev_out); > res.type = RTN_LOCAL; > goto select_source; > @@ -1065,7 +1065,7 @@ select_source: > fl.fld_src = fl.fld_dst; > if (dev_out) > dev_put(dev_out); > - dev_out = &loopback_dev; > + dev_out = loopback_dev; > dev_hold(dev_out); > fl.oif = dev_out->ifindex; > if (res.fi) > diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c > index 5b77bda..808f529 100644 > --- a/net/ipv4/devinet.c > +++ b/net/ipv4/devinet.c > @@ -203,7 +203,7 @@ static void inetdev_destroy(struct in_device *in_dev) > ASSERT_RTNL(); > > dev = in_dev->dev; > - if (dev == &loopback_dev) > + if (dev == loopback_dev) > return; > > in_dev->dead = 1; > @@ -1058,7 +1058,7 @@ static int inetdev_event(struct notifier_block *this, unsigned long event, > in_dev = inetdev_init(dev); > if (!in_dev) > return notifier_from_errno(-ENOMEM); > - if (dev == &loopback_dev) { > + if (dev == loopback_dev) { > IN_DEV_CONF_SET(in_dev, NOXFRM, 1); > IN_DEV_CONF_SET(in_dev, NOPOLICY, 1); > } > @@ -1074,7 +1074,7 @@ static int inetdev_event(struct notifier_block *this, unsigned long event, > case NETDEV_UP: > if (dev->mtu < 68) > break; > - if (dev == &loopback_dev) { > + if (dev == loopback_dev) { > struct in_ifaddr *ifa; > if ((ifa = inet_alloc_ifa()) != NULL) { > ifa->ifa_local = > diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c > index c5b2470..3ec7690 100644 > --- a/net/ipv4/ipconfig.c > +++ b/net/ipv4/ipconfig.c > @@ -189,11 +189,11 @@ static int __init ic_open_devs(void) > rtnl_lock(); > > /* bring loopback device up first */ > - if (dev_change_flags(&loopback_dev, loopback_dev.flags | IFF_UP) < 0) > - printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev.name); > + if (dev_change_flags(loopback_dev, loopback_dev->flags | IFF_UP) < 0) > + printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev->name); > > for_each_netdev(dev) { > - if (dev == &loopback_dev) > + if (dev == loopback_dev) > continue; > if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) : > (!(dev->flags & IFF_LOOPBACK) && > diff --git a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c > index f005a2f..7450326 100644 > --- a/net/ipv4/ipvs/ip_vs_core.c > +++ b/net/ipv4/ipvs/ip_vs_core.c > @@ -961,7 +961,7 @@ ip_vs_in(unsigned int hooknum, struct sk_buff **pskb, > * ... don't know why 1st test DOES NOT include 2nd (?) > */ > if (unlikely(skb->pkt_type != PACKET_HOST > - || skb->dev == &loopback_dev || skb->sk)) { > + || skb->dev == loopback_dev || skb->sk)) { > IP_VS_DBG(12, "packet type=%d proto=%d daddr=%d.%d.%d.%d ignored\n", > skb->pkt_type, > ip_hdr(skb)->protocol, > diff --git a/net/ipv4/route.c b/net/ipv4/route.c > index c7ca94b..4f13385 100644 > --- a/net/ipv4/route.c > +++ b/net/ipv4/route.c > @@ -1404,8 +1404,8 @@ static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, > { > struct rtable *rt = (struct rtable *) dst; > struct in_device *idev = rt->idev; > - if (dev != &loopback_dev && idev && idev->dev == dev) { > - struct in_device *loopback_idev = in_dev_get(&loopback_dev); > + if (dev != loopback_dev && idev && idev->dev == dev) { > + struct in_device *loopback_idev = in_dev_get(loopback_dev); > if (loopback_idev) { > rt->idev = loopback_idev; > in_dev_put(idev); > @@ -1557,7 +1557,7 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, > #endif > rth->rt_iif = > rth->fl.iif = dev->ifindex; > - rth->u.dst.dev = &loopback_dev; > + rth->u.dst.dev = loopback_dev; > dev_hold(rth->u.dst.dev); > rth->idev = in_dev_get(rth->u.dst.dev); > rth->fl.oif = 0; > @@ -1814,7 +1814,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, > if (res.type == RTN_LOCAL) { > int result; > result = fib_validate_source(saddr, daddr, tos, > - loopback_dev.ifindex, > + loopback_dev->ifindex, > dev, &spec_dst, &itag); > if (result < 0) > goto martian_source; > @@ -1881,7 +1881,7 @@ local_input: > #endif > rth->rt_iif = > rth->fl.iif = dev->ifindex; > - rth->u.dst.dev = &loopback_dev; > + rth->u.dst.dev = loopback_dev; > dev_hold(rth->u.dst.dev); > rth->idev = in_dev_get(rth->u.dst.dev); > rth->rt_gateway = daddr; > @@ -2151,7 +2151,7 @@ static int ip_route_output_slow(struct rtable **rp, const struct flowi *oldflp) > RT_SCOPE_UNIVERSE), > } }, > .mark = oldflp->mark, > - .iif = loopback_dev.ifindex, > + .iif = loopback_dev->ifindex, > .oif = oldflp->oif }; > struct fib_result res; > unsigned flags = 0; > @@ -2245,9 +2245,9 @@ static int ip_route_output_slow(struct rtable **rp, const struct flowi *oldflp) > fl.fl4_dst = fl.fl4_src = htonl(INADDR_LOOPBACK); > if (dev_out) > dev_put(dev_out); > - dev_out = &loopback_dev; > + dev_out = loopback_dev; > dev_hold(dev_out); > - fl.oif = loopback_dev.ifindex; > + fl.oif = loopback_dev->ifindex; > res.type = RTN_LOCAL; > flags |= RTCF_LOCAL; > goto make_route; > @@ -2292,7 +2292,7 @@ static int ip_route_output_slow(struct rtable **rp, const struct flowi *oldflp) > fl.fl4_src = fl.fl4_dst; > if (dev_out) > dev_put(dev_out); > - dev_out = &loopback_dev; > + dev_out = loopback_dev; > dev_hold(dev_out); > fl.oif = dev_out->ifindex; > if (res.fi) > diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c > index 4ff8ed3..29ab3de 100644 > --- a/net/ipv4/xfrm4_policy.c > +++ b/net/ipv4/xfrm4_policy.c > @@ -306,7 +306,7 @@ static void xfrm4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, > > xdst = (struct xfrm_dst *)dst; > if (xdst->u.rt.idev->dev == dev) { > - struct in_device *loopback_idev = in_dev_get(&loopback_dev); > + struct in_device *loopback_idev = in_dev_get(loopback_dev); > BUG_ON(!loopback_idev); > > do { > diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c > index 91ef3be..d806f89 100644 > --- a/net/ipv6/addrconf.c > +++ b/net/ipv6/addrconf.c > @@ -2399,7 +2399,7 @@ static int addrconf_ifdown(struct net_device *dev, int how) > > ASSERT_RTNL(); > > - if (dev == &loopback_dev && how == 1) > + if (dev == loopback_dev && how == 1) > how = 0; > > rt6_ifdown(dev); > @@ -4203,16 +4203,19 @@ int __init addrconf_init(void) > * device and it being up should be removed. > */ > rtnl_lock(); > - if (!ipv6_add_dev(&loopback_dev)) > + if (!ipv6_add_dev(loopback_dev)) > err = -ENOMEM; > rtnl_unlock(); > if (err) > return err; > > - ip6_null_entry.rt6i_idev = in6_dev_get(&loopback_dev); > + ip6_null_entry.u.dst.dev = loopback_dev; > + ip6_null_entry.rt6i_idev = in6_dev_get(loopback_dev); > #ifdef CONFIG_IPV6_MULTIPLE_TABLES > - ip6_prohibit_entry.rt6i_idev = in6_dev_get(&loopback_dev); > - ip6_blk_hole_entry.rt6i_idev = in6_dev_get(&loopback_dev); > + ip6_prohibit_entry.u.dst.dev = loopback_dev; > + ip6_prohibit_entry.rt6i_idev = in6_dev_get(loopback_dev); > + ip6_blk_hole_entry.u.dst.dev = loopback_dev; > + ip6_blk_hole_entry.rt6i_idev = in6_dev_get(loopback_dev); > #endif > > register_netdevice_notifier(&ipv6_dev_notf); > @@ -4267,7 +4270,7 @@ void __exit addrconf_cleanup(void) > continue; > addrconf_ifdown(dev, 1); > } > - addrconf_ifdown(&loopback_dev, 2); > + addrconf_ifdown(loopback_dev, 2); > > /* > * Check hash table. > diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c > index 30a5cb1..15d7910 100644 > --- a/net/ipv6/ip6_input.c > +++ b/net/ipv6/ip6_input.c > @@ -86,7 +86,7 @@ int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt > * > * BTW, when we send a packet for our own local address on a > * non-loopback interface (e.g. ethX), it is being delivered > - * via the loopback interface (lo) here; skb->dev = &loopback_dev. > + * via the loopback interface (lo) here; skb->dev = loopback_dev. > * It, however, should be considered as if it is being > * arrived via the sending interface (ethX), because of the > * nature of scoping architecture. --yoshfuji > diff --git a/net/ipv6/netfilter/ip6t_REJECT.c b/net/ipv6/netfilter/ip6t_REJECT.c > index 2f487cd..5086053 100644 > --- a/net/ipv6/netfilter/ip6t_REJECT.c > +++ b/net/ipv6/netfilter/ip6t_REJECT.c > @@ -167,7 +167,7 @@ static inline void > send_unreach(struct sk_buff *skb_in, unsigned char code, unsigned int hooknum) > { > if (hooknum == NF_IP6_LOCAL_OUT && skb_in->dev == NULL) > - skb_in->dev = &loopback_dev; > + skb_in->dev = loopback_dev; > > icmpv6_send(skb_in, ICMPV6_DEST_UNREACH, code, 0, NULL); > } > diff --git a/net/ipv6/route.c b/net/ipv6/route.c > index 55ea80f..3f5c65f 100644 > --- a/net/ipv6/route.c > +++ b/net/ipv6/route.c > @@ -137,7 +137,6 @@ struct rt6_info ip6_null_entry = { > .dst = { > .__refcnt = ATOMIC_INIT(1), > .__use = 1, > - .dev = &loopback_dev, > .obsolete = -1, > .error = -ENETUNREACH, > .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, > @@ -163,7 +162,6 @@ struct rt6_info ip6_prohibit_entry = { > .dst = { > .__refcnt = ATOMIC_INIT(1), > .__use = 1, > - .dev = &loopback_dev, > .obsolete = -1, > .error = -EACCES, > .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, > @@ -183,7 +181,6 @@ struct rt6_info ip6_blk_hole_entry = { > .dst = { > .__refcnt = ATOMIC_INIT(1), > .__use = 1, > - .dev = &loopback_dev, > .obsolete = -1, > .error = -EINVAL, > .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, > @@ -223,8 +220,8 @@ static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, > struct rt6_info *rt = (struct rt6_info *)dst; > struct inet6_dev *idev = rt->rt6i_idev; > > - if (dev != &loopback_dev && idev != NULL && idev->dev == dev) { > - struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev); > + if (dev != loopback_dev && idev != NULL && idev->dev == dev) { > + struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev); > if (loopback_idev != NULL) { > rt->rt6i_idev = loopback_idev; > in6_dev_put(idev); > @@ -1187,12 +1184,12 @@ int ip6_route_add(struct fib6_config *cfg) > if ((cfg->fc_flags & RTF_REJECT) || > (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) { > /* hold loopback dev/idev if we haven't done so. */ > - if (dev != &loopback_dev) { > + if (dev != loopback_dev) { > if (dev) { > dev_put(dev); > in6_dev_put(idev); > } > - dev = &loopback_dev; > + dev = loopback_dev; > dev_hold(dev); > idev = in6_dev_get(dev); > if (!idev) { > @@ -1896,13 +1893,13 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, > if (rt == NULL) > return ERR_PTR(-ENOMEM); > > - dev_hold(&loopback_dev); > + dev_hold(loopback_dev); > in6_dev_hold(idev); > > rt->u.dst.flags = DST_HOST; > rt->u.dst.input = ip6_input; > rt->u.dst.output = ip6_output; > - rt->rt6i_dev = &loopback_dev; > + rt->rt6i_dev = loopback_dev; > rt->rt6i_idev = idev; > rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev); > rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst)); > diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c > index 3ec0c47..cc07216 100644 > --- a/net/ipv6/xfrm6_policy.c > +++ b/net/ipv6/xfrm6_policy.c > @@ -375,7 +375,7 @@ static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, > > xdst = (struct xfrm_dst *)dst; > if (xdst->u.rt6.rt6i_idev->dev == dev) { > - struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev); > + struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev); > BUG_ON(!loopback_idev); > > do { > diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c > index c7b2503..ca37eec 100644 > --- a/net/xfrm/xfrm_policy.c > +++ b/net/xfrm/xfrm_policy.c > @@ -1947,8 +1947,8 @@ static int stale_bundle(struct dst_entry *dst) > void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) > { > while ((dst = dst->child) && dst->xfrm && dst->dev == dev) { > - dst->dev = &loopback_dev; > - dev_hold(&loopback_dev); > + dst->dev = loopback_dev; > + dev_hold(dst->dev); > dev_put(dev); > } > } _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers