[PATCH 1/8] nvmet: add debugfs support

[Hannes Reinecke]

On 3/25/24 19:18, Daniel Wagner wrote:
> On Fri, Mar 22, 2024 at 08:03:26AM +0100, Hannes Reinecke wrote:
>> +static ssize_t nvmet_ctrl_state_write(struct file *file, const char __user *buf,
>> +				      size_t count, loff_t *ppos)
>> +{
>> +	struct seq_file *m = file->private_data;
>> +	struct nvmet_ctrl *ctrl = m->private;
>> +	char reset[16];
>> +
>> +	if (count >= sizeof(reset))
>> +		return -EINVAL;
>> +	if (copy_from_user(reset, buf, count))
>> +		return -EFAULT;
>> +	if (!memcmp(reset, "fatal", 5))
>> +		nvmet_ctrl_fatal_error(ctrl);
> 
> I'd like to use this also to trigger a reset. This allows to test the
> auth code a bit better, e.g. after changing the ctrl key on the target
> nothing will happen until a reconnect happens. Currently, I have to
> set the max queue count which triggers a reset. Also it would make the
> 'support real hardware' series for blktests why more generic.
> 
> This here should does the trick in my local testing:
> 
> --- a/drivers/nvme/target/debugfs.c
> +++ b/drivers/nvme/target/debugfs.c
> @@ -157,6 +157,8 @@ static ssize_t nvmet_ctrl_state_write(struct file *file, const char __user *buf,
>                  return -EFAULT;
>          if (!memcmp(reset, "fatal", 5))
>                  nvmet_ctrl_fatal_error(ctrl);
> +       else if (!memcmp(reset, "reset", 5))
> +               ctrl->ops->delete_ctrl(ctrl);
>          else
>                  return -EINVAL;
>          return count;
> 

Weelll ... guess what the 'fatal' status does ...
I can rename it to 'reset' if you'd like, but 'fatal' corresponds to one 
of the controller states, whereas 'reset' doesn't.
But I can make it an alias if you really want to write 'reset' :-)

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare at suse.de                                +49 911 74053 688
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