add storage and helpers to associate an ipv{4,6} address
with the local route to self. This will be used by a
later patch to implement early demux for unconnected UDP
sockets.
The caches are filled on address creation, with DST_OBSOLETE_NONE.
Ipv6 cache are explicitly clearered and refreshed on underlaying
device down/up events.
The above schema is simpler than refreshing the cache every
time the dst expires under the default obsolete schema.
Signed-off-by: Paolo Abeni <pab...@redhat.com>
---
include/linux/inetdevice.h | 4 ++++
include/net/addrconf.h | 3 +++
include/net/if_inet6.h | 4 ++++
net/ipv4/devinet.c | 29 ++++++++++++++++++++++++++++-
net/ipv6/addrconf.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 83 insertions(+), 1 deletion(-)
diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index 751d051f0bc7..c29982f178bb 100644
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -130,6 +130,8 @@ static inline void ipv4_devconf_setall(struct in_device
*in_dev)
#define IN_DEV_ARP_IGNORE(in_dev) IN_DEV_MAXCONF((in_dev), ARP_IGNORE)
#define IN_DEV_ARP_NOTIFY(in_dev) IN_DEV_MAXCONF((in_dev), ARP_NOTIFY)
+struct dst_entry;
+
struct in_ifaddr {
struct hlist_node hash;
struct in_ifaddr *ifa_next;
@@ -149,6 +151,7 @@ struct in_ifaddr {
__u32 ifa_preferred_lft;
unsigned long ifa_cstamp; /* created timestamp */
unsigned long ifa_tstamp; /* updated timestamp */
+ struct dst_entry *dst; /* local route to self */
};
struct in_validator_info {
@@ -180,6 +183,7 @@ __be32 inet_confirm_addr(struct net *net, struct in_device
*in_dev, __be32 dst,
struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
__be32 mask);
struct in_ifaddr *inet_lookup_ifaddr_rcu(struct net *net, __be32 addr);
+struct dst_entry *inet_get_ifaddr_dst_rcu(struct net *net, __be32 addr);
static __inline__ bool inet_ifa_match(__be32 addr, struct in_ifaddr *ifa)
{
return !((addr^ifa->ifa_address)&ifa->ifa_mask);
diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 87981cd63180..bdfa3306a4c5 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -87,6 +87,9 @@ struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
const struct in6_addr *addr,
struct net_device *dev, int strict);
+struct dst_entry *inet6_get_ifaddr_dst_rcu_bh(struct net *net,
+ const struct in6_addr *addr);
+
int ipv6_dev_get_saddr(struct net *net, const struct net_device *dev,
const struct in6_addr *daddr, unsigned int srcprefs,
struct in6_addr *saddr);
diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h
index d4088d1a688d..1dd42e7c17a4 100644
--- a/include/net/if_inet6.h
+++ b/include/net/if_inet6.h
@@ -39,6 +39,8 @@ enum {
INET6_IFADDR_STATE_DEAD,
};
+struct dst_entry;
+
struct inet6_ifaddr {
struct in6_addr addr;
__u32 prefix_len;
@@ -77,6 +79,8 @@ struct inet6_ifaddr {
struct rcu_head rcu;
struct in6_addr peer_addr;
+
+ struct dst_entry *dst; /* local route to self */
};
struct ip6_sf_socklist {
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 7ce22a2c07ce..a7748f787866 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -179,6 +179,17 @@ struct in_ifaddr *inet_lookup_ifaddr_rcu(struct net *net,
__be32 addr)
return NULL;
}
+/* called under RCU lock */
+struct dst_entry *inet_get_ifaddr_dst_rcu(struct net *net, __be32 addr)
+{
+ struct in_ifaddr *ifa = inet_lookup_ifaddr_rcu(net, addr);
+
+ if (!ifa)
+ return NULL;
+
+ return dst_access(&ifa->dst, 0);
+}
+
static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
@@ -337,6 +348,7 @@ static void __inet_del_ifa(struct in_device *in_dev, struct
in_ifaddr **ifap,
struct in_ifaddr *last_prim = in_dev->ifa_list;
struct in_ifaddr *prev_prom = NULL;
int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
+ struct dst_entry *dst;
ASSERT_RTNL();
@@ -395,7 +407,12 @@ static void __inet_del_ifa(struct in_device *in_dev,
struct in_ifaddr **ifap,
*ifap = ifa1->ifa_next;
inet_hash_remove(ifa1);
- /* 3. Announce address deletion */
+ /* 3. Clear dst cache */
+
+ dst = xchg(&ifa1->dst, NULL);
+ dst_release(dst);
+
+ /* 4. Announce address deletion */
/* Send message first, then call notifier.
At first sight, FIB update triggered by notifier
@@ -449,6 +466,7 @@ static int __inet_insert_ifa(struct in_ifaddr *ifa, struct
nlmsghdr *nlh,
struct in_device *in_dev = ifa->ifa_dev;
struct in_ifaddr *ifa1, **ifap, **last_primary;
struct in_validator_info ivi;
+ struct rtable *rt;
int ret;
ASSERT_RTNL();
@@ -516,6 +534,15 @@ static int __inet_insert_ifa(struct in_ifaddr *ifa, struct
nlmsghdr *nlh,
rtmsg_ifa(RTM_NEWADDR, ifa, nlh, portid);
blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
+ /* fill the dst cache and transfer the dst ownership to it */
+ rt = ip_local_route_alloc(in_dev->dev, 0, 0, RTN_LOCAL, false);
+ if (rt) {
+ /* the local route will be valid for till the address will be
+ * up
+ */
+ rt->dst.obsolete = DST_OBSOLETE_NONE;
+ __dst_update(&ifa->dst, &rt->dst);
+ }
return 0;
}
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 5940062cac8d..5fa8d1b764ca 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -904,6 +904,26 @@ static int addrconf_fixup_linkdown(struct ctl_table
*table, int *p, int newf)
#endif
+static void inet6_addr_dst_clear(struct inet6_ifaddr *ifp)
+{
+ dst_release(xchg(&ifp->dst, NULL));
+}
+
+static void inet6_addr_dst_update(struct inet6_dev *idev,
+ struct inet6_ifaddr *ifp)
+{
+ struct rt6_info *rt = addrconf_dst_alloc(idev, &ifp->addr, false);
+
+ if (IS_ERR(rt))
+ return;
+
+ /* we are going to manully clear the cache when the related dev will
+ * go down
+ */
+ rt->dst.obsolete = DST_OBSOLETE_NONE;
+ __dst_update(&ifp->dst, &rt->dst);
+}
+
/* Nobody refers to this ifaddr, destroy it */
void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
{
@@ -914,6 +934,7 @@ void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
#endif
in6_dev_put(ifp->idev);
+ inet6_addr_dst_clear(ifp);
if (cancel_delayed_work(&ifp->dad_work))
pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
@@ -1907,6 +1928,18 @@ int ipv6_chk_prefix(const struct in6_addr *addr, struct
net_device *dev)
}
EXPORT_SYMBOL(ipv6_chk_prefix);
+/* called under RCU lock */
+struct dst_entry *inet6_get_ifaddr_dst_rcu_bh(struct net *net,
+ const struct in6_addr *addr)
+{
+ struct inet6_ifaddr *ifp = ipv6_lookup_ifaddr_rcu_bh(net, addr);
+
+ if (!ifp)
+ return NULL;
+
+ return dst_access(&ifp->dst, 0);
+}
+
struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr
*addr,
struct net_device *dev, int strict)
{
@@ -3300,6 +3333,15 @@ static int fixup_permanent_addr(struct inet6_dev *idev,
ifp->rt = rt;
spin_unlock(&ifp->lock);
+ /* if dad is not going to start, we must cache the new route
+ * elsewhere we can just clear the old one
+ */
+ if (ifp->state == INET6_IFADDR_STATE_PREDAD ||
+ ifp->flags & IFA_F_TENTATIVE)
+ inet6_addr_dst_clear(ifp);
+ else
+ inet6_addr_dst_update(idev, ifp);
+
ip6_rt_put(prev);
}
@@ -3679,6 +3721,7 @@ static int addrconf_ifdown(struct net_device *dev, int
how)
spin_unlock_bh(&ifa->lock);
+ inet6_addr_dst_clear(ifa);
if (rt)
ip6_del_rt(rt);
@@ -4009,6 +4052,7 @@ static void addrconf_dad_completed(struct inet6_ifaddr
*ifp, bool bump_id)
*/
ipv6_ifa_notify(RTM_NEWADDR, ifp);
+ inet6_addr_dst_update(ifp->idev, ifp);
/* If added prefix is link local and we are prepared to process
router advertisements, start sending router solicitations.
--
2.13.5
