Re: [PATCH 1/4] scsi: libsas: Add sas_execute_internal_abort_single()

[Hannes Reinecke <hare@suse.de>]

On 3/3/22 13:18, John Garry wrote:
> The internal abort feature is common to hisi_sas and pm8001 HBAs, and the
> driver support is similar also, so add a common handler.
> 
> Two modes of operation will be supported:
> - single: Abort a single tagged command
> - device: Abort all commands associated with a specific domain device
> 
> A new protocol is added, SAS_PROTOCOL_INTERNAL_ABORT, so the common queue
> command API may be re-used.
> 
> Only add "single" support as a first step.
> 
> Signed-off-by: John Garry <john.garry@huawei.com>
> ---
>   drivers/scsi/libsas/sas_scsi_host.c | 75 +++++++++++++++++++++++++++++
>   include/scsi/libsas.h               | 14 ++++++
>   include/scsi/sas.h                  |  2 +
>   3 files changed, 91 insertions(+)
> 
> diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c
> index 5b5747e33dbd..0d05826e6e8c 100644
> --- a/drivers/scsi/libsas/sas_scsi_host.c
> +++ b/drivers/scsi/libsas/sas_scsi_host.c
> @@ -920,6 +920,81 @@ void sas_task_internal_timedout(struct timer_list *t)
>   #define TASK_TIMEOUT			(20 * HZ)
>   #define TASK_RETRY			3
>   
> +static int sas_execute_internal_abort(struct domain_device *device,
> +				      enum sas_internal_abort type, u16 tag,
> +				      unsigned int qid, void *data)
> +{
> +	struct sas_ha_struct *ha = device->port->ha;
> +	struct sas_internal *i = to_sas_internal(ha->core.shost->transportt);
> +	struct sas_task *task = NULL;
> +	int res, retry;
> +
> +	for (retry = 0; retry < TASK_RETRY; retry++) {
> +		task = sas_alloc_slow_task(GFP_KERNEL);
> +		if (!task)
> +			return -ENOMEM;
> +
> +		task->dev = device;
> +		task->task_proto = SAS_PROTOCOL_INTERNAL_ABORT;
> +		task->task_done = sas_task_internal_done;
> +		task->slow_task->timer.function = sas_task_internal_timedout;
> +		task->slow_task->timer.expires = jiffies + TASK_TIMEOUT;
> +		add_timer(&task->slow_task->timer);
> +
> +		task->abort_task.tag = tag;
> +		task->abort_task.type = type;
> +
> +		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
> +		if (res) {
> +			del_timer_sync(&task->slow_task->timer);
> +			pr_err("Executing internal abort failed %016llx (%d)\n",
> +			       SAS_ADDR(device->sas_addr), res);
> +			break;
> +		}
> +
> +		wait_for_completion(&task->slow_task->completion);
> +		res = TMF_RESP_FUNC_FAILED;
> +
> +		/* Even if the internal abort timed out, return direct. */
> +		if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
> +			pr_err("Internal abort: timeout %016llx\n",
> +			       SAS_ADDR(device->sas_addr));
> +
> +			res = -EIO;
> +			break;
> +		}
> +
> +		if (task->task_status.resp == SAS_TASK_COMPLETE &&
> +			task->task_status.stat == SAS_SAM_STAT_GOOD) {
> +			res = TMF_RESP_FUNC_COMPLETE;
> +			break;
> +		}
> +
> +		if (task->task_status.resp == SAS_TASK_COMPLETE &&
> +			task->task_status.stat == TMF_RESP_FUNC_SUCC) {
> +			res = TMF_RESP_FUNC_SUCC;
> +			break;
> +		}
> +
> +		pr_err("Internal abort: task to dev %016llx response: 0x%x status 0x%x\n",
> +		       SAS_ADDR(device->sas_addr), task->task_status.resp,
> +		       task->task_status.stat);
> +		sas_free_task(task);
> +		task = NULL;
> +	}
> +	BUG_ON(retry == TASK_RETRY && task != NULL);
> +	sas_free_task(task);
> +	return res;
> +}
> +
> +int sas_execute_internal_abort_single(struct domain_device *device, u16 tag,
> +				      unsigned int qid, void *data)
> +{
> +	return sas_execute_internal_abort(device, SAS_INTERNAL_ABORT_SINGLE,
> +					  tag, qid, data);
> +}
> +EXPORT_SYMBOL_GPL(sas_execute_internal_abort_single);
> +
>   int sas_execute_tmf(struct domain_device *device, void *parameter,
>   		    int para_len, int force_phy_id,
>   		    struct sas_tmf_task *tmf)
> diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h
> index df2c8fc43429..2d30d57916e5 100644
> --- a/include/scsi/libsas.h
> +++ b/include/scsi/libsas.h
> @@ -557,6 +557,16 @@ struct sas_ata_task {
>   	int    force_phy_id;
>   };
>   
> +/* LLDDs rely on these values */
> +enum sas_internal_abort {
> +	SAS_INTERNAL_ABORT_SINGLE	= 0,
> +};
> +

Why don't you use the existing TMF_XXX values here?
Your 'single' method pretty much _is_ a TMF_ABORT_TASK, and the 'device' 
method _is_ a TMF_ABORT_TASK_SET, no?

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		           Kernel Storage Architect
hare@suse.de			                  +49 911 74053 688
SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg
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