mirror of
https://github.com/torvalds/linux
synced 2024-10-11 05:46:41 +00:00
e1ee0a5ba3
Dump all the FIB tables in each net namespace upon registration to the FIB notification chain so that the callee will have a complete view of the tables. The integrity of the dump is ensured by a per-table sequence counter that is incremented (under write lock) whenever a route is added or deleted from the table. All the sequence counters are read (under each table's read lock) and summed, prior and after the dump. In case the counters differ, then the dump is either restarted or the registration fails. While it's possible for a table to be modified after its counter has been read, this isn't really a problem. In case it happened before it was read the second time, then the comparison at the end will fail. If it happened afterwards, then we're guaranteed to be notified about the change, as the notification block is registered prior to the second read. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
62 lines
1.4 KiB
C
62 lines
1.4 KiB
C
#include <linux/notifier.h>
|
|
#include <linux/socket.h>
|
|
#include <linux/kernel.h>
|
|
#include <net/net_namespace.h>
|
|
#include <net/fib_notifier.h>
|
|
#include <net/netns/ipv6.h>
|
|
#include <net/ip6_fib.h>
|
|
|
|
int call_fib6_notifier(struct notifier_block *nb, struct net *net,
|
|
enum fib_event_type event_type,
|
|
struct fib_notifier_info *info)
|
|
{
|
|
info->family = AF_INET6;
|
|
return call_fib_notifier(nb, net, event_type, info);
|
|
}
|
|
|
|
int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
|
|
struct fib_notifier_info *info)
|
|
{
|
|
info->family = AF_INET6;
|
|
return call_fib_notifiers(net, event_type, info);
|
|
}
|
|
|
|
static unsigned int fib6_seq_read(struct net *net)
|
|
{
|
|
return fib6_tables_seq_read(net) + fib6_rules_seq_read(net);
|
|
}
|
|
|
|
static int fib6_dump(struct net *net, struct notifier_block *nb)
|
|
{
|
|
int err;
|
|
|
|
err = fib6_rules_dump(net, nb);
|
|
if (err)
|
|
return err;
|
|
|
|
return fib6_tables_dump(net, nb);
|
|
}
|
|
|
|
static const struct fib_notifier_ops fib6_notifier_ops_template = {
|
|
.family = AF_INET6,
|
|
.fib_seq_read = fib6_seq_read,
|
|
.fib_dump = fib6_dump,
|
|
};
|
|
|
|
int __net_init fib6_notifier_init(struct net *net)
|
|
{
|
|
struct fib_notifier_ops *ops;
|
|
|
|
ops = fib_notifier_ops_register(&fib6_notifier_ops_template, net);
|
|
if (IS_ERR(ops))
|
|
return PTR_ERR(ops);
|
|
net->ipv6.notifier_ops = ops;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void __net_exit fib6_notifier_exit(struct net *net)
|
|
{
|
|
fib_notifier_ops_unregister(net->ipv6.notifier_ops);
|
|
}
|