net: Loopback ifindex is constant now

As pointed out, there are places, that access net->loopback_dev->ifindex
and after ifindex generation is made per-net this value becomes constant
equals 1. So go ahead and introduce the LOOPBACK_IFINDEX constant and use
it where appropriate.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Pavel Emelyanov 2012-08-08 21:53:36 +00:00 committed by David S. Miller
parent aa79e66eee
commit 1fb9489bf1
8 changed files with 18 additions and 10 deletions

View File

@ -197,6 +197,7 @@ static __net_init int loopback_net_init(struct net *net)
if (err) if (err)
goto out_free_netdev; goto out_free_netdev;
BUG_ON(dev->ifindex != LOOPBACK_IFINDEX);
net->loopback_dev = dev; net->loopback_dev = dev;
return 0; return 0;

View File

@ -105,6 +105,13 @@ struct net {
struct sock *diag_nlsk; struct sock *diag_nlsk;
}; };
/*
* ifindex generation is per-net namespace, and loopback is
* always the 1st device in ns (see net_dev_init), thus any
* loopback device should get ifindex 1
*/
#define LOOPBACK_IFINDEX 1
#include <linux/seq_file_net.h> #include <linux/seq_file_net.h>

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@ -961,7 +961,7 @@ static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *o
.saddr = oldflp->saddr, .saddr = oldflp->saddr,
.flowidn_scope = RT_SCOPE_UNIVERSE, .flowidn_scope = RT_SCOPE_UNIVERSE,
.flowidn_mark = oldflp->flowidn_mark, .flowidn_mark = oldflp->flowidn_mark,
.flowidn_iif = init_net.loopback_dev->ifindex, .flowidn_iif = LOOPBACK_IFINDEX,
.flowidn_oif = oldflp->flowidn_oif, .flowidn_oif = oldflp->flowidn_oif,
}; };
struct dn_route *rt = NULL; struct dn_route *rt = NULL;
@ -979,7 +979,7 @@ static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *o
"dn_route_output_slow: dst=%04x src=%04x mark=%d" "dn_route_output_slow: dst=%04x src=%04x mark=%d"
" iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr), " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
le16_to_cpu(oldflp->saddr), le16_to_cpu(oldflp->saddr),
oldflp->flowidn_mark, init_net.loopback_dev->ifindex, oldflp->flowidn_mark, LOOPBACK_IFINDEX,
oldflp->flowidn_oif); oldflp->flowidn_oif);
/* If we have an output interface, verify its a DECnet device */ /* If we have an output interface, verify its a DECnet device */
@ -1042,7 +1042,7 @@ source_ok:
if (!fld.daddr) if (!fld.daddr)
goto out; goto out;
} }
fld.flowidn_oif = init_net.loopback_dev->ifindex; fld.flowidn_oif = LOOPBACK_IFINDEX;
res.type = RTN_LOCAL; res.type = RTN_LOCAL;
goto make_route; goto make_route;
} }

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@ -218,7 +218,7 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
scope = RT_SCOPE_UNIVERSE; scope = RT_SCOPE_UNIVERSE;
if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) { if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) {
fl4.flowi4_oif = 0; fl4.flowi4_oif = 0;
fl4.flowi4_iif = net->loopback_dev->ifindex; fl4.flowi4_iif = LOOPBACK_IFINDEX;
fl4.daddr = ip_hdr(skb)->saddr; fl4.daddr = ip_hdr(skb)->saddr;
fl4.saddr = 0; fl4.saddr = 0;
fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos); fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);

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@ -1798,7 +1798,7 @@ static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
.flowi4_oif = (rt_is_output_route(rt) ? .flowi4_oif = (rt_is_output_route(rt) ?
skb->dev->ifindex : 0), skb->dev->ifindex : 0),
.flowi4_iif = (rt_is_output_route(rt) ? .flowi4_iif = (rt_is_output_route(rt) ?
net->loopback_dev->ifindex : LOOPBACK_IFINDEX :
skb->dev->ifindex), skb->dev->ifindex),
.flowi4_mark = skb->mark, .flowi4_mark = skb->mark,
}; };

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@ -85,7 +85,7 @@ static bool rpfilter_mt(const struct sk_buff *skb, struct xt_action_param *par)
return ipv4_is_local_multicast(iph->daddr) ^ invert; return ipv4_is_local_multicast(iph->daddr) ^ invert;
flow.flowi4_iif = 0; flow.flowi4_iif = 0;
} else { } else {
flow.flowi4_iif = dev_net(par->in)->loopback_dev->ifindex; flow.flowi4_iif = LOOPBACK_IFINDEX;
} }
flow.daddr = iph->saddr; flow.daddr = iph->saddr;

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@ -1619,7 +1619,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
if (res.type == RTN_LOCAL) { if (res.type == RTN_LOCAL) {
err = fib_validate_source(skb, saddr, daddr, tos, err = fib_validate_source(skb, saddr, daddr, tos,
net->loopback_dev->ifindex, LOOPBACK_IFINDEX,
dev, in_dev, &itag); dev, in_dev, &itag);
if (err < 0) if (err < 0)
goto martian_source_keep_err; goto martian_source_keep_err;
@ -1895,7 +1895,7 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
orig_oif = fl4->flowi4_oif; orig_oif = fl4->flowi4_oif;
fl4->flowi4_iif = net->loopback_dev->ifindex; fl4->flowi4_iif = LOOPBACK_IFINDEX;
fl4->flowi4_tos = tos & IPTOS_RT_MASK; fl4->flowi4_tos = tos & IPTOS_RT_MASK;
fl4->flowi4_scope = ((tos & RTO_ONLINK) ? fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
RT_SCOPE_LINK : RT_SCOPE_UNIVERSE); RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
@ -1984,7 +1984,7 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
if (!fl4->daddr) if (!fl4->daddr)
fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
dev_out = net->loopback_dev; dev_out = net->loopback_dev;
fl4->flowi4_oif = net->loopback_dev->ifindex; fl4->flowi4_oif = LOOPBACK_IFINDEX;
res.type = RTN_LOCAL; res.type = RTN_LOCAL;
flags |= RTCF_LOCAL; flags |= RTCF_LOCAL;
goto make_route; goto make_route;

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@ -965,7 +965,7 @@ struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk,
{ {
int flags = 0; int flags = 0;
fl6->flowi6_iif = net->loopback_dev->ifindex; fl6->flowi6_iif = LOOPBACK_IFINDEX;
if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr)) if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr))
flags |= RT6_LOOKUP_F_IFACE; flags |= RT6_LOOKUP_F_IFACE;