Re: net devices: Get network devices to show up in sysfs.

[Jeff Garzik]

On Mon, Jan 06, 2003 at 07:50:37PM +0000, Linux Kernel Mailing List wrote:
> ChangeSet 1.838.151.11, 2003/01/06 13:50:37-06:00, [e-mail]
> 
> 	net devices: Get network devices to show up in sysfs.
> 	
> 	- declare net_subsys, and register during net_dev_init().
> 	- Add kobject to struct net_device.
> 	- initialize name and register in register_netdevice().
> 	- remove in unregister_netdevice().
> 	
> diff -Nru a/include/linux/netdevice.h b/include/linux/netdevice.h
> --- a/include/linux/netdevice.h	Tue Jan  7 13:06:05 2003
> +++ b/include/linux/netdevice.h	Tue Jan  7 13:06:05 2003
> @@ -28,6 +28,7 @@
>  #include <linux/if.h>
>  #include <linux/if_ether.h>
>  #include <linux/if_packet.h>
> +#include <linux/kobject.h>
>  
>  #include <asm/atomic.h>
>  #include <asm/cache.h>
> @@ -438,6 +439,9 @@
>  	/* this will get initialized at each interface type init routine */
>  	struct divert_blk	*divert;
>  #endif /* CONFIG_NET_DIVERT */
> +
> +	/* generic object representation */
> +	struct kobject kobj;
>  };

Just curious, is this needed purely for reference counting, or mainly to
hook into sysfs?  If the former, net devices already have reference
counting, so I want to make sure kobjects do not run afoul of that.

> +static struct subsystem net_subsys;
> +
>  
>  /*******************************************************************************
>  
> @@ -2545,7 +2547,10 @@
>  	notifier_call_chain(&netdev_chain, NETDEV_REGISTER, dev);
>  
>  	net_run_sbin_hotplug(dev, "register");
> -	ret = 0;
> +
> +	snprintf(dev->kobj.name,KOBJ_NAME_LEN,dev->name);
> +	kobj_set_kset_s(dev,net_subsys);
> +	ret = kobject_register(&dev->kobj);

If the return code matters, shouldn't you be checking for its success?

> @@ -2671,6 +2676,8 @@
>  		goto out;
>  	}
>  
> +	kobject_unregister(&dev->kobj);
> +

...especially if kobject_register failed above

	Jeff