xsk: refactor xdp_umem_assign_dev()

Return early and only take the ref on dev once there is no possibility
of failing.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2018-07-30 20:43:52 -07:00 committed by David S. Miller
parent c29c2ebd2a
commit f734607e81

View File

@ -56,41 +56,34 @@ int xdp_umem_assign_dev(struct xdp_umem *umem, struct net_device *dev,
if (force_copy)
return 0;
if (!dev->netdev_ops->ndo_bpf || !dev->netdev_ops->ndo_xsk_async_xmit)
return force_zc ? -ENOTSUPP : 0; /* fail or fallback */
bpf.command = XDP_QUERY_XSK_UMEM;
rtnl_lock();
err = dev->netdev_ops->ndo_bpf(dev, &bpf);
rtnl_unlock();
if (err)
return force_zc ? -ENOTSUPP : 0;
bpf.command = XDP_SETUP_XSK_UMEM;
bpf.xsk.umem = umem;
bpf.xsk.queue_id = queue_id;
rtnl_lock();
err = dev->netdev_ops->ndo_bpf(dev, &bpf);
rtnl_unlock();
if (err)
return force_zc ? err : 0; /* fail or fallback */
dev_hold(dev);
if (dev->netdev_ops->ndo_bpf && dev->netdev_ops->ndo_xsk_async_xmit) {
bpf.command = XDP_QUERY_XSK_UMEM;
rtnl_lock();
err = dev->netdev_ops->ndo_bpf(dev, &bpf);
rtnl_unlock();
if (err) {
dev_put(dev);
return force_zc ? -ENOTSUPP : 0;
}
bpf.command = XDP_SETUP_XSK_UMEM;
bpf.xsk.umem = umem;
bpf.xsk.queue_id = queue_id;
rtnl_lock();
err = dev->netdev_ops->ndo_bpf(dev, &bpf);
rtnl_unlock();
if (err) {
dev_put(dev);
return force_zc ? err : 0; /* fail or fallback */
}
umem->dev = dev;
umem->queue_id = queue_id;
umem->zc = true;
return 0;
}
dev_put(dev);
return force_zc ? -ENOTSUPP : 0; /* fail or fallback */
umem->dev = dev;
umem->queue_id = queue_id;
umem->zc = true;
return 0;
}
static void xdp_umem_clear_dev(struct xdp_umem *umem)