Re: [RFCv2 bluetooth-next 02/16] ieee802154: 6lowpan: register packet layer while open

[Alexander Aring <alex.aring@gmail.com>]

On Sun, Aug 30, 2015 at 11:48:28PM +0200, Stefan Schmidt wrote:
> Hello.
> 
> On 20/08/15 18:47, Alexander Aring wrote:
> >This patch moves the open count handling while doing open of a lowpan
> >interface. We need the packet handler register at first when one lowpan
> >interface is up.
> The code itself looks fine, but I have trouble to gte the why from your
> commit message. Why is this change needed?
> 

It's a slightly improvement. There exists a small case when ALL lowpan
interfaces are down and the ieee802154_6lowpan module still receives
frames. We don't need to receive frames when all lowpan interfaces are
down. This will end always in the upcomming (!netif_running(ldev))
condition.

Does it sounds useful?

> >Signed-off-by: Alexander Aring <alex.aring@gmail.com>
> >---
> >  net/ieee802154/6lowpan/core.c | 28 ++++++++++++++++++----------
> >  1 file changed, 18 insertions(+), 10 deletions(-)
> >
> >diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c
> >index 3cc76f0..8e9da1d 100644
> >--- a/net/ieee802154/6lowpan/core.c
> >+++ b/net/ieee802154/6lowpan/core.c
> >@@ -76,9 +76,27 @@ static int lowpan_dev_init(struct net_device *ldev)
> >  	return 0;
> >  }
> >+static int lowpan_open(struct net_device *dev)
> >+{
> >+	if (!open_count)
> >+		lowpan_rx_init();
> >+	open_count++;
> >+	return 0;
> >+}
> >+
> >+static int lowpan_stop(struct net_device *dev)
> >+{
> >+	open_count--;
> >+	if (!open_count)
> >+		lowpan_rx_exit();
> >+	return 0;
> >+}
> >+
> >  static const struct net_device_ops lowpan_netdev_ops = {
> >  	.ndo_init		= lowpan_dev_init,
> >  	.ndo_start_xmit		= lowpan_xmit,
> >+	.ndo_open		= lowpan_open,
> >+	.ndo_stop		= lowpan_stop,
> >  };
> >  static void lowpan_setup(struct net_device *ldev)
> >@@ -149,11 +167,6 @@ static int lowpan_newlink(struct net *src_net, struct net_device *ldev,
> >  	}
> >  	wdev->ieee802154_ptr->lowpan_dev = ldev;
> >-	if (!open_count)
> >-		lowpan_rx_init();
> >-
> >-	open_count++;
> >-
> >  	return 0;
> >  }
> >@@ -163,11 +176,6 @@ static void lowpan_dellink(struct net_device *ldev, struct list_head *head)
> >  	ASSERT_RTNL();
> >-	open_count--;
> >-
> >-	if (!open_count)
> >-		lowpan_rx_exit();
> >-
> >  	wdev->ieee802154_ptr->lowpan_dev = NULL;
> >  	unregister_netdevice(ldev);
> >  	dev_put(wdev);
> 
> Signed-off-by: Stefan Schmidt <stefan@osg.samsung.com>
> 

Why is this a SOB?

- Alex