[PATCH v3 2/2] scsi: storvsc: Add support for FC rport.

From: Cathy Avery
Date: Mon Apr 17 2017 - 14:38:22 EST


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.

This patch stubs in an rport per fc_host and sets its rport role
as FC_PORT_ROLE_FCP_DUMMY_INITIATOR to indicate to the fc_transport
that it is a pseudo rport in order to scan the scsi stack via
echo "- - -" > /sys/class/scsi_host/hostX/scan.

Signed-off-by: Cathy Avery <cavery@xxxxxxxxxx>
---
drivers/scsi/storvsc_drv.c | 23 ++++++++++++++++++-----
1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 016639d..1ec8579 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -476,6 +476,9 @@ 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 {
@@ -1823,19 +1826,27 @@ static int storvsc_probe(struct hv_device *device,
target = (device->dev_instance.b[5] << 8 |
device->dev_instance.b[4]);
ret = scsi_add_device(host, 0, target, 0);
- if (ret) {
- scsi_remove_host(host);
- goto err_out2;
- }
+ if (ret)
+ goto err_out3;
}
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
if (host->transportt == fc_transport_template) {
+ struct fc_rport_identifiers ids = {
+ .roles = FC_PORT_ROLE_FCP_DUMMY_INITIATOR,
+ };
+
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);
+ if (!stor_device->rport)
+ goto err_out3;
}
#endif
return 0;

+err_out3:
+ scsi_remove_host(host);
+
err_out2:
/*
* Once we have connected with the host, we would need to
@@ -1861,8 +1872,10 @@ 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);
--
2.5.0