From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= Subject: [RFC PATCH bpf-next 01/12] xsk: remove rebind support Date: Tue, 15 May 2018 21:06:04 +0200 Message-ID: <20180515190615.23099-2-bjorn.topel@gmail.com> References: <20180515190615.23099-1-bjorn.topel@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , michael.lundkvist@ericsson.com, jesse.brandeburg@intel.com, anjali.singhai@intel.com, qi.z.zhang@intel.com, intel-wired-lan@lists.osuosl.org To: bjorn.topel@gmail.com, magnus.karlsson@gmail.com, magnus.karlsson@intel.com, alexander.h.duyck@intel.com, alexander.duyck@gmail.com, john.fastabend@gmail.com, ast@fb.com, brouer@redhat.com, willemdebruijn.kernel@gmail.com, daniel@iogearbox.net, mst@redhat.com, netdev@vger.kernel.org Return-path: Received: from mga05.intel.com ([192.55.52.43]:33643 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751104AbeEOTGk (ORCPT ); Tue, 15 May 2018 15:06:40 -0400 In-Reply-To: <20180515190615.23099-1-bjorn.topel@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Björn Töpel Supporting rebind, i.e. after a successful bind the process can call bind again without closing the socket, makes the setup state machine more complex. Let us constrain the state space, but not supporting rebind. Signed-off-by: Björn Töpel --- net/xdp/xsk.c | 30 +++++++++--------------------- 1 file changed, 9 insertions(+), 21 deletions(-) diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 009c5af5bba5..e59ca8e2618d 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -236,14 +236,6 @@ static int xsk_init_queue(u32 entries, struct xsk_queue **queue, return 0; } -static void __xsk_release(struct xdp_sock *xs) -{ - /* Wait for driver to stop using the xdp socket. */ - synchronize_net(); - - dev_put(xs->dev); -} - static int xsk_release(struct socket *sock) { struct sock *sk = sock->sk; @@ -260,7 +252,9 @@ static int xsk_release(struct socket *sock) local_bh_enable(); if (xs->dev) { - __xsk_release(xs); + /* Wait for driver to stop using the xdp socket. */ + synchronize_net(); + dev_put(xs->dev); xs->dev = NULL; } @@ -294,9 +288,8 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) { struct sockaddr_xdp *sxdp = (struct sockaddr_xdp *)addr; struct sock *sk = sock->sk; - struct net_device *dev, *dev_curr; struct xdp_sock *xs = xdp_sk(sk); - struct xdp_umem *old_umem = NULL; + struct net_device *dev; int err = 0; if (addr_len < sizeof(struct sockaddr_xdp)) @@ -305,7 +298,11 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) return -EINVAL; mutex_lock(&xs->mutex); - dev_curr = xs->dev; + if (xs->dev) { + err = -EBUSY; + goto out_release; + } + dev = dev_get_by_index(sock_net(sk), sxdp->sxdp_ifindex); if (!dev) { err = -ENODEV; @@ -352,7 +349,6 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) } xdp_get_umem(umem_xs->umem); - old_umem = xs->umem; xs->umem = umem_xs->umem; sockfd_put(sock); } else if (!xs->umem || !xdp_umem_validate_queues(xs->umem)) { @@ -364,14 +360,6 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) xskq_set_umem(xs->umem->cq, &xs->umem->props); } - /* Rebind? */ - if (dev_curr && (dev_curr != dev || - xs->queue_id != sxdp->sxdp_queue_id)) { - __xsk_release(xs); - if (old_umem) - xdp_put_umem(old_umem); - } - xs->dev = dev; xs->queue_id = sxdp->sxdp_queue_id; -- 2.14.1