[NET]: Move destructor from neigh->ops to neigh_params

struct neigh_ops currently has a destructor field, which no in-kernel
drivers outside of infiniband use.  The infiniband/ulp/ipoib in-tree
driver stashes some info in the neighbour structure (the results of
the second-stage lookup from ARP results to real link-level path), and
it uses neigh->ops->destructor to get a callback so it can clean up
this extra info when a neighbour is freed.  We've run into problems
with this: since the destructor is in an ops field that is shared
between neighbours that may belong to different net devices, there's
no way to set/clear it safely.

The following patch moves this field to neigh_parms where it can be
safely set, together with its twin neigh_setup.  Two additional
patches in the patch series update ipoib to use this new interface.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Michael S. Tsirkin 2006-03-20 22:25:41 -08:00 committed by David S. Miller
parent 53dcb0e38c
commit c5ecd62c25
3 changed files with 4 additions and 18 deletions

View File

@ -247,7 +247,6 @@ static void path_free(struct net_device *dev, struct ipoib_path *path)
if (neigh->ah)
ipoib_put_ah(neigh->ah);
*to_ipoib_neigh(neigh->neighbour) = NULL;
neigh->neighbour->ops->destructor = NULL;
kfree(neigh);
}
@ -530,7 +529,6 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
err:
*to_ipoib_neigh(skb->dst->neighbour) = NULL;
list_del(&neigh->list);
neigh->neighbour->ops->destructor = NULL;
kfree(neigh);
++priv->stats.tx_dropped;
@ -769,21 +767,9 @@ static void ipoib_neigh_destructor(struct neighbour *n)
ipoib_put_ah(ah);
}
static int ipoib_neigh_setup(struct neighbour *neigh)
{
/*
* Is this kosher? I can't find anybody in the kernel that
* sets neigh->destructor, so we should be able to set it here
* without trouble.
*/
neigh->ops->destructor = ipoib_neigh_destructor;
return 0;
}
static int ipoib_neigh_setup_dev(struct net_device *dev, struct neigh_parms *parms)
{
parms->neigh_setup = ipoib_neigh_setup;
parms->neigh_destructor = ipoib_neigh_destructor;
return 0;
}

View File

@ -68,6 +68,7 @@ struct neigh_parms
struct net_device *dev;
struct neigh_parms *next;
int (*neigh_setup)(struct neighbour *);
void (*neigh_destructor)(struct neighbour *);
struct neigh_table *tbl;
void *sysctl_table;
@ -145,7 +146,6 @@ struct neighbour
struct neigh_ops
{
int family;
void (*destructor)(struct neighbour *);
void (*solicit)(struct neighbour *, struct sk_buff*);
void (*error_report)(struct neighbour *, struct sk_buff*);
int (*output)(struct sk_buff*);

View File

@ -586,8 +586,8 @@ void neigh_destroy(struct neighbour *neigh)
kfree(hh);
}
if (neigh->ops && neigh->ops->destructor)
(neigh->ops->destructor)(neigh);
if (neigh->parms->neigh_destructor)
(neigh->parms->neigh_destructor)(neigh);
skb_queue_purge(&neigh->arp_queue);