From f734607e819b951bae3b436b026ec672082e9241 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 30 Jul 2018 20:43:52 -0700 Subject: [PATCH] xsk: refactor xdp_umem_assign_dev() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Return early and only take the ref on dev once there is no possibility of failing. Signed-off-by: Jakub Kicinski Reviewed-by: Quentin Monnet Acked-by: Björn Töpel Signed-off-by: David S. Miller --- net/xdp/xdp_umem.c | 49 ++++++++++++++++++++-------------------------- 1 file changed, 21 insertions(+), 28 deletions(-) diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index f47abb46c587..c199d66b5f3f 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -56,41 +56,34 @@ int xdp_umem_assign_dev(struct xdp_umem *umem, struct net_device *dev, if (force_copy) return 0; - dev_hold(dev); + if (!dev->netdev_ops->ndo_bpf || !dev->netdev_ops->ndo_xsk_async_xmit) + return force_zc ? -ENOTSUPP : 0; /* fail or fallback */ - if (dev->netdev_ops->ndo_bpf && dev->netdev_ops->ndo_xsk_async_xmit) { - bpf.command = XDP_QUERY_XSK_UMEM; + bpf.command = XDP_QUERY_XSK_UMEM; - rtnl_lock(); - err = dev->netdev_ops->ndo_bpf(dev, &bpf); - rtnl_unlock(); + rtnl_lock(); + err = dev->netdev_ops->ndo_bpf(dev, &bpf); + rtnl_unlock(); - if (err) { - dev_put(dev); - return force_zc ? -ENOTSUPP : 0; - } + if (err) + return force_zc ? -ENOTSUPP : 0; - bpf.command = XDP_SETUP_XSK_UMEM; - bpf.xsk.umem = umem; - bpf.xsk.queue_id = queue_id; + 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(); + 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; - } + if (err) + return force_zc ? err : 0; /* fail or fallback */ - dev_put(dev); - return force_zc ? -ENOTSUPP : 0; /* fail or fallback */ + dev_hold(dev); + umem->dev = dev; + umem->queue_id = queue_id; + umem->zc = true; + return 0; } static void xdp_umem_clear_dev(struct xdp_umem *umem) -- 2.39.5