Re: [patch 5/7] genhd: send async notification on media change

[Tejun Heo <htejun@gmail.com>]

Kristen Carlson Accardi wrote:
> Send an uevent to user space to indicate that a media change event has occurred.
> 
> Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
> 
> Index: 2.6-git/block/genhd.c
> ===================================================================
> --- 2.6-git.orig/block/genhd.c
> +++ 2.6-git/block/genhd.c
> @@ -643,6 +643,25 @@ struct seq_operations diskstats_op = {
>  	.show	= diskstats_show
>  };
>  
> +static void media_change_notify_thread(struct work_struct *work)
> +{
> +	struct gendisk *gd = container_of(work, struct gendisk, async_notify);
> +	char event[] = "MEDIA_CHANGE=1";
> +	char *envp[] = { event, NULL };
> +
> +	/*
> +	 * set enviroment vars to indicate which event this is for
> +	 * so that user space will know to go check the media status.
> +	 */
> +	kobject_uevent_env(&gd->kobj, KOBJ_CHANGE, envp);
> +}
> +
> +void genhd_media_change_notify(struct gendisk *disk)
> +{
> +	schedule_work(&disk->async_notify);
> +}
> +EXPORT_SYMBOL_GPL(genhd_media_change_notify);

genhd might go away while async_notify work is in-flight.  You'll need
to either grab a reference or wait for the work to finish in release
routine.

-- 
tejun