Re: [PATCH v2 05/14] nvmet: Send an AEN on CCR completion

[Hannes Reinecke <hare@suse.de>]

On 2/3/26 19:48, Mohamed Khalfella wrote:
> On Tue 2026-02-03 04:27:39 +0100, Hannes Reinecke wrote:
>> On 1/30/26 23:34, Mohamed Khalfella wrote:
>>> Send an AEN to initiator when impacted controller exists. The
>>> notification points to CCR log page that initiator can read to check
>>> which CCR operation completed.
>>>
>>> Signed-off-by: Mohamed Khalfella <mkhalfella@purestorage.com>
>>> ---
>>>    drivers/nvme/target/core.c  | 25 ++++++++++++++++++++++---
>>>    drivers/nvme/target/nvmet.h |  3 ++-
>>>    include/linux/nvme.h        |  3 +++
>>>    3 files changed, 27 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
>>> index 54dd0dcfa12b..ae2fe9f90bcd 100644
>>> --- a/drivers/nvme/target/core.c
>>> +++ b/drivers/nvme/target/core.c
>>> @@ -202,7 +202,7 @@ static void nvmet_async_event_work(struct work_struct *work)
>>>    	nvmet_async_events_process(ctrl);
>>>    }
>>>    
>>> -void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
>>> +static void nvmet_add_async_event_locked(struct nvmet_ctrl *ctrl, u8 event_type,
>>>    		u8 event_info, u8 log_page)
>>>    {
>>>    	struct nvmet_async_event *aen;
>>> @@ -215,13 +215,19 @@ void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
>>>    	aen->event_info = event_info;
>>>    	aen->log_page = log_page;
>>>    
>>> -	mutex_lock(&ctrl->lock);
>>>    	list_add_tail(&aen->entry, &ctrl->async_events);
>>> -	mutex_unlock(&ctrl->lock);
>>>    
>>>    	queue_work(nvmet_wq, &ctrl->async_event_work);
>>>    }
>>>    
>>> +void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
>>> +		u8 event_info, u8 log_page)
>>> +{
>>> +	mutex_lock(&ctrl->lock);
>>> +	nvmet_add_async_event_locked(ctrl, event_type, event_info, log_page);
>>> +	mutex_unlock(&ctrl->lock);
>>> +}
>>> +
>>>    static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid)
>>>    {
>>>    	u32 i;
>>> @@ -1788,6 +1794,18 @@ struct nvmet_ctrl *nvmet_alloc_ctrl(struct nvmet_alloc_ctrl_args *args)
>>>    }
>>>    EXPORT_SYMBOL_GPL(nvmet_alloc_ctrl);
>>>    
>>> +static void nvmet_ctrl_notify_ccr(struct nvmet_ctrl *ctrl)
>>> +{
>>> +	lockdep_assert_held(&ctrl->lock);
>>> +
>>> +	if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_CCR_COMPLETE))
>>> +		return;
>>> +
>>> +	nvmet_add_async_event_locked(ctrl, NVME_AER_NOTICE,
>>> +				     NVME_AER_NOTICE_CCR_COMPLETED,
>>> +				     NVME_LOG_CCR);
>>> +}
>>> +
>>>    static void nvmet_ctrl_complete_pending_ccr(struct nvmet_ctrl *ctrl)
>>>    {
>>>    	struct nvmet_subsys *subsys = ctrl->subsys;
>>
>> But what does the CCR command actually _do_?
>> At the very lease I would have expected it to trigger a controller reset
>> (eg calling into nvmet_ctrl_fatal_error()), yet I don't see it doing
>> that anywhere ...
> 
> [PATCH v2 03/14] nvmet: Implement CCR nvme command
> is where impacted controller is told to fail. It does exactly what you
> mentioned above.
> 
> +out_unlock:
> +       mutex_unlock(&sctrl->lock);
> +       if (status == NVME_SC_SUCCESS)
> +               nvmet_ctrl_fatal_error(ictrl);
> +       nvmet_ctrl_put(ictrl);
> +out:
> +       nvmet_req_complete(req, status);
> 
> I refactored the error handling codepath into success codepath. That is
> why I think it is kind of hidden. If this is not obvious I can separate
> the two codepaths. What do you think?

Ah. Indeed, cleverly hidden.

So ignore my comment.

Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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