phonet netlink: allow multiple messages per skb in route dump

My previous patch to this file changed the code to be bug-compatible
towards userspace. Unless userspace (which I wasn't able to find)
implements the dump reader by hand in a wrong way, this isn't needed.
If it uses libnl or similar code putting multiple messages into a
single SKB is far more efficient.

Change the code to do this. While at it, also clean it up and don't
use so many variables - just store the address in the callback args
directly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Johannes Berg 2015-01-19 12:15:24 +01:00 committed by David S. Miller
parent fc83477780
commit 926e9878a3

View file

@ -272,31 +272,23 @@ static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
static int route_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
u8 addr, addr_idx = 0, addr_start_idx = cb->args[0];
u8 addr;
rcu_read_lock();
for (addr = 0; addr < 64; addr++) {
struct net_device *dev;
for (addr = cb->args[0]; addr < 64; addr++) {
struct net_device *dev = phonet_route_get_rcu(net, addr << 2);
dev = phonet_route_get_rcu(net, addr << 2);
if (!dev)
continue;
if (addr_idx++ < addr_start_idx)
continue;
fill_route(skb, dev, addr << 2, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, RTM_NEWROUTE);
/* fill_route() used to return > 0 (or negative errors) but
* never 0 - ignore the return value and just go out to
* call dumpit again from outside to preserve the behavior
*/
goto out;
if (fill_route(skb, dev, addr << 2, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, RTM_NEWROUTE) < 0)
goto out;
}
out:
rcu_read_unlock();
cb->args[0] = addr_idx;
cb->args[1] = 0;
cb->args[0] = addr;
return skb->len;
}