Re: [PATCH v4 01/21] ibmvfc: add vhost fields and defaults for MQ enablement

John Garry
2021-01-12T11:45:31Z

On 11/01/2021 23:12, Tyrel Datwyler wrote:
> Introduce several new vhost fields for managing MQ state of the adapter
> as well as initial defaults for MQ enablement.
>
> Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
> ---
> drivers/scsi/ibmvscsi/ibmvfc.c | 8 ++++++++
> drivers/scsi/ibmvscsi/ibmvfc.h | 9 +++++++++
> 2 files changed, 17 insertions(+)
>
> diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
> index ba95438a8912..9200fe49c57e 100644
> --- a/drivers/scsi/ibmvscsi/ibmvfc.c
> +++ b/drivers/scsi/ibmvscsi/ibmvfc.c
> @@ -3302,6 +3302,7 @@ static struct scsi_host_template driver_template = {
> .max_sectors = IBMVFC_MAX_SECTORS,
> .shost_attrs = ibmvfc_attrs,
> .track_queue_depth = 1,
> + .host_tagset = 1,

Good to see another user :)

I didn't check the whole series very thoroughly, but I guess that you
only need to set this when shost->nr_hw_queues > 1. Having said that, it
should be fine when shost->nr_hw_queues = 0 or 1.

Thanks,
John

> };
>
> /**
> @@ -5290,6 +5291,7 @@ static int ibmvfc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
> shost->max_sectors = IBMVFC_MAX_SECTORS;
> shost->max_cmd_len = IBMVFC_MAX_CDB_LEN;
> shost->unique_id = shost->host_no;
> + shost->nr_hw_queues = IBMVFC_MQ ? IBMVFC_SCSI_HW_QUEUES : 1;
>
> vhost = shost_priv(shost);
> INIT_LIST_HEAD(&vhost->targets);
> @@ -5300,6 +5302,12 @@ static int ibmvfc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
> vhost->partition_number = -1;
> vhost->log_level = log_level;
> vhost->task_set = 1;
> +
> + vhost->mq_enabled = IBMVFC_MQ;
> + vhost->client_scsi_channels = IBMVFC_SCSI_CHANNELS;
> + vhost->using_channels = 0;
> + vhost->do_enquiry = 1;
> +
> strcpy(vhost->partition_name, "UNKNOWN");
> init_waitqueue_head(&vhost->work_wait_q);
> init_waitqueue_head(&vhost->init_wait_q);
> diff --git a/drivers/scsi/ibmvscsi/ibmvfc.h b/drivers/scsi/ibmvscsi/ibmvfc.h
> index 632e977449c5..dd6d89292867 100644
> --- a/drivers/scsi/ibmvscsi/ibmvfc.h
> +++ b/drivers/scsi/ibmvscsi/ibmvfc.h
> @@ -41,6 +41,11 @@
> #define IBMVFC_DEFAULT_LOG_LEVEL 2
> #define IBMVFC_MAX_CDB_LEN 16
> #define IBMVFC_CLS3_ERROR 0
> +#define IBMVFC_MQ 0
> +#define IBMVFC_SCSI_CHANNELS 0
> +#define IBMVFC_SCSI_HW_QUEUES 1
> +#define IBMVFC_MIG_NO_SUB_TO_CRQ 0
> +#define IBMVFC_MIG_NO_N_TO_M 0
>
> /*
> * Ensure we have resources for ERP and initialization:
> @@ -840,6 +845,10 @@ struct ibmvfc_host {
> int delay_init;
> int scan_complete;
> int logged_in;
> + int mq_enabled;
> + int using_channels;
> + int do_enquiry;
> + int client_scsi_channels;
> int aborting_passthru;
> int events_to_log;
> #define IBMVFC_AE_LINKUP 0x0001
>