Re: [RFC PATCH] netlink: Increase netlink dump skb message size

[Eric Dumazet <eric.dumazet@gmail.com>]

Le lundi 25 avril 2011 à 15:01 -0700, Greg Rose a écrit :
> The message size allocated for rtnl info dumps was limited to a single page.
> This is not enough for additional interface info available with devices
> that support SR-IOV.  Check that the amount of data allocated is sufficient
> for the amount of data requested.
> 
> Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
> ---
> 
>  include/linux/rtnetlink.h |    1 +
>  net/core/rtnetlink.c      |    6 ++++++
>  net/netlink/af_netlink.c  |   37 +++++++++++++++++++++++++++++++------
>  3 files changed, 38 insertions(+), 6 deletions(-)
> 

Hmm, thats a hack, because netlink_dump() is generic and you add
something very specific.

I prefer something that allows one dump() to reallocate a bigger skb

Maybe changing->dump() prototype to struct sk_buff **pskb instead of
struct sk_buff *skb.

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index c8f35b5..7fa6735 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1681,7 +1681,7 @@ static int netlink_dump(struct sock *sk)
 		goto errout_skb;
 	}
 
-	len = cb->dump(skb, cb);
+	len = cb->dump(&skb, cb);
 
 	if (len > 0) {
 		mutex_unlock(nlk->cb_mutex);