| Message ID | 1477932510-28594-7-git-send-email-jgross@suse.com |
|---|---|
| State | Awaiting Upstream, archived |
| Delegated to: | David Miller |
| Headers | show |
> -----Original Message----- > From: Juergen Gross [mailto:jgross@suse.com] > Sent: 31 October 2016 16:48 > To: linux-kernel@vger.kernel.org; xen-devel@lists.xen.org > Cc: David Vrabel <david.vrabel@citrix.com>; boris.ostrovsky@oracle.com; > Juergen Gross <jgross@suse.com>; Wei Liu <wei.liu2@citrix.com>; Paul > Durrant <Paul.Durrant@citrix.com>; netdev@vger.kernel.org > Subject: [PATCH 06/12] xen: make use of xenbus_read_unsigned() in xen- > netback > > 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 Reviewed-by: Paul Durrant <paul.durrant@citrix.com> > Cc: netdev@vger.kernel.org > > Signed-off-by: Juergen Gross <jgross@suse.com> > --- > 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
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; }
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 <jgross@suse.com> --- drivers/net/xen-netback/xenbus.c | 50 +++++++++++----------------------------- 1 file changed, 14 insertions(+), 36 deletions(-)