Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S944670AbcJaQta (ORCPT ); Mon, 31 Oct 2016 12:49:30 -0400 Received: from mx2.suse.de ([195.135.220.15]:52549 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S944609AbcJaQs4 (ORCPT ); Mon, 31 Oct 2016 12:48:56 -0400 From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xen.org Cc: david.vrabel@citrix.com, boris.ostrovsky@oracle.com, Juergen Gross , wei.liu2@citrix.com, paul.durrant@citrix.com, netdev@vger.kernel.org Subject: [PATCH 06/12] xen: make use of xenbus_read_unsigned() in xen-netback Date: Mon, 31 Oct 2016 17:48:24 +0100 Message-Id: <1477932510-28594-7-git-send-email-jgross@suse.com> X-Mailer: git-send-email 2.6.6 In-Reply-To: <1477932510-28594-1-git-send-email-jgross@suse.com> References: <1477932510-28594-1-git-send-email-jgross@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3887 Lines: 114 Use xenbus_read_unsigned() instead of xenbus_scanf() when possible. This requires to change the type of some reads from int to unsigned, but these cases have been wrong before: negative values are not allowed for the modified cases. Cc: wei.liu2@citrix.com Cc: paul.durrant@citrix.com Cc: netdev@vger.kernel.org Signed-off-by: Juergen Gross --- drivers/net/xen-netback/xenbus.c | 50 +++++++++++----------------------------- 1 file changed, 14 insertions(+), 36 deletions(-) diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c index 8674e18..7356e00 100644 --- a/drivers/net/xen-netback/xenbus.c +++ b/drivers/net/xen-netback/xenbus.c @@ -785,12 +785,9 @@ static void xen_mcast_ctrl_changed(struct xenbus_watch *watch, struct xenvif *vif = container_of(watch, struct xenvif, mcast_ctrl_watch); struct xenbus_device *dev = xenvif_to_xenbus_device(vif); - int val; - if (xenbus_scanf(XBT_NIL, dev->otherend, - "request-multicast-control", "%d", &val) < 0) - val = 0; - vif->multicast_control = !!val; + vif->multicast_control = !!xenbus_read_unsigned(dev->otherend, + "request-multicast-control", 0); } static int xen_register_mcast_ctrl_watch(struct xenbus_device *dev, @@ -934,12 +931,9 @@ static void connect(struct backend_info *be) /* Check whether the frontend requested multiple queues * and read the number requested. */ - err = xenbus_scanf(XBT_NIL, dev->otherend, - "multi-queue-num-queues", - "%u", &requested_num_queues); - if (err < 0) { - requested_num_queues = 1; /* Fall back to single queue */ - } else if (requested_num_queues > xenvif_max_queues) { + requested_num_queues = xenbus_read_unsigned(dev->otherend, + "multi-queue-num-queues", 1); + if (requested_num_queues > xenvif_max_queues) { /* buggy or malicious guest */ xenbus_dev_fatal(dev, err, "guest requested %u queues, exceeding the maximum of %u.", @@ -1134,7 +1128,7 @@ static int read_xenbus_vif_flags(struct backend_info *be) struct xenvif *vif = be->vif; struct xenbus_device *dev = be->dev; unsigned int rx_copy; - int err, val; + int err; err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u", &rx_copy); @@ -1150,10 +1144,7 @@ static int read_xenbus_vif_flags(struct backend_info *be) if (!rx_copy) return -EOPNOTSUPP; - if (xenbus_scanf(XBT_NIL, dev->otherend, - "feature-rx-notify", "%d", &val) < 0) - val = 0; - if (!val) { + if (!xenbus_read_unsigned(dev->otherend, "feature-rx-notify", 0)) { /* - Reduce drain timeout to poll more frequently for * Rx requests. * - Disable Rx stall detection. @@ -1162,34 +1153,21 @@ static int read_xenbus_vif_flags(struct backend_info *be) be->vif->stall_timeout = 0; } - if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-sg", - "%d", &val) < 0) - val = 0; - vif->can_sg = !!val; + vif->can_sg = !!xenbus_read_unsigned(dev->otherend, "feature-sg", 0); vif->gso_mask = 0; - if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4", - "%d", &val) < 0) - val = 0; - if (val) + if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv4", 0)) vif->gso_mask |= GSO_BIT(TCPV4); - if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6", - "%d", &val) < 0) - val = 0; - if (val) + if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv6", 0)) vif->gso_mask |= GSO_BIT(TCPV6); - if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-no-csum-offload", - "%d", &val) < 0) - val = 0; - vif->ip_csum = !val; + vif->ip_csum = !xenbus_read_unsigned(dev->otherend, + "feature-no-csum-offload", 0); - if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-ipv6-csum-offload", - "%d", &val) < 0) - val = 0; - vif->ipv6_csum = !!val; + vif->ipv6_csum = !!xenbus_read_unsigned(dev->otherend, + "feature-ipv6-csum-offload", 0); return 0; } -- 2.6.6