[PATCH] scsi: storvsc: Add support for FC rport.

[Cathy Avery]

Hi,

I haven't received any feedback yet.

Should I resend?

Thanks,

Cathy

On 02/28/2017 01:45 PM, Cathy Avery wrote:
> Included in the current storvsc driver for Hyper-V is the ability
> to access luns on an FC fabric via a virtualized fiber channel
> adapter exposed by the Hyper-V host. The driver also attaches to the FC
> transport to allow host and port names to be published under
> /sys/class/fc_host/hostX. Current customer tools running on the VM
> require that these names be available in the well known standard
> location under fc_host/hostX.
>
> A problem arose when attaching to the FC transport. The scsi_scan
> code attempts to call fc_user_scan which has basically become a no-op
> due to the fact that the virtualized FC device does not expose rports.
> At this point you cannot refresh the scsi bus after mapping or unmapping
> luns on the SAN without a reboot of the VM.
>
> This patch stubs in an rport per fc_host in storvsc so that the
> requirement of a defined rport is now met within the fc_transport and
> echo "- - -" > /sys/class/scsi_host/hostX/scan now works.
>
> Signed-off-by: Cathy Avery <cavery at redhat.com>
> ---
>   drivers/scsi/storvsc_drv.c | 15 ++++++++++++++-
>   1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
> index 585e54f..6d7b932 100644
> --- a/drivers/scsi/storvsc_drv.c
> +++ b/drivers/scsi/storvsc_drv.c
> @@ -478,6 +478,9 @@ struct storvsc_device {
>   	 */
>   	u64 node_name;
>   	u64 port_name;
> +#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
> +	struct fc_rport *rport;
> +#endif
>   };
>   
>   struct hv_host_device {
> @@ -1823,8 +1826,16 @@ static int storvsc_probe(struct hv_device *device,
>   	}
>   #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
>   	if (host->transportt == fc_transport_template) {
> +		struct fc_rport_identifiers ids;
> +
> +		ids.node_name = 0;
> +		ids.port_name = 0;
> +		ids.port_id = 0;
> +		ids.roles |= FC_PORT_ROLE_FCP_TARGET;
> +
>   		fc_host_node_name(host) = stor_device->node_name;
>   		fc_host_port_name(host) = stor_device->port_name;
> +		stor_device->rport = fc_remote_port_add(host, 0, &ids);
>   	}
>   #endif
>   	return 0;
> @@ -1854,8 +1865,10 @@ static int storvsc_remove(struct hv_device *dev)
>   	struct Scsi_Host *host = stor_device->host;
>   
>   #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
> -	if (host->transportt == fc_transport_template)
> +	if (host->transportt == fc_transport_template) {
> +		fc_remote_port_delete(stor_device->rport);
>   		fc_remove_host(host);
> +	}
>   #endif
>   	scsi_remove_host(host);
>   	storvsc_dev_remove(dev);