[PATCH net-next] net-sysfs: trigger netlink notification on ifalias change via sysfs

[PATCH net-next] net-sysfs: trigger netlink notification on ifalias change via sysfs

[Roopa Prabhu]

From: Roopa Prabhu <roopa@cumulusnetworks.com>

This patch adds netlink notifications on iflias changes via sysfs.
makes it consistent with the netlink path which also calls
netdev_state_change. Also makes it consistent with other sysfs
netdev_store operations.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
---
 net/core/net-sysfs.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 51d5836..799b752 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -382,7 +382,7 @@ static ssize_t ifalias_store(struct device *dev, struct device_attribute *attr,
 	struct net_device *netdev = to_net_dev(dev);
 	struct net *net = dev_net(netdev);
 	size_t count = len;
-	ssize_t ret;
+	ssize_t ret = 0;
 
 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 		return -EPERM;
@@ -391,9 +391,20 @@ static ssize_t ifalias_store(struct device *dev, struct device_attribute *attr,
 	if (len >  0 && buf[len - 1] == '\n')
 		--count;
 
-	ret = dev_set_alias(netdev, buf, count);
+	if (!rtnl_trylock())
+		return restart_syscall();
+
+	if (dev_isalive(netdev)) {
+		ret = dev_set_alias(netdev, buf, count);
+		if (ret < 0)
+			goto err;
+		ret = len;
+		netdev_state_change(netdev);
+	}
+err:
+	rtnl_unlock();
 
-	return ret < 0 ? ret : len;
+	return ret;
 }
 
 static ssize_t ifalias_show(struct device *dev,
-- 
2.1.4

Re: [PATCH net-next] net-sysfs: trigger netlink notification on ifalias change via sysfs

[Jiri Pirko]

Tue, Nov 14, 2017 at 08:21:36AM CET, roopa@cumulusnetworks.com wrote:
>From: Roopa Prabhu <roopa@cumulusnetworks.com>
>
>This patch adds netlink notifications on iflias changes via sysfs.
>makes it consistent with the netlink path which also calls
>netdev_state_change. Also makes it consistent with other sysfs
>netdev_store operations.
>
>Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>

Reviewed-by: Jiri Pirko <jiri@mellanox.com>

Re: [PATCH net-next] net-sysfs: trigger netlink notification on ifalias change via sysfs

[David Miller]

From: Roopa Prabhu <roopa@cumulusnetworks.com>
Date: Mon, 13 Nov 2017 23:21:36 -0800

> From: Roopa Prabhu <roopa@cumulusnetworks.com>
> 
> This patch adds netlink notifications on iflias changes via sysfs.
> makes it consistent with the netlink path which also calls
> netdev_state_change. Also makes it consistent with other sysfs
> netdev_store operations.
> 
> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>

Applied.