target/pscsi: Don't leak scsi_host if hba is VIRTUAL_HOST

See https://bugzilla.redhat.com/show_bug.cgi?id=1025672

We need to put() the reference to the scsi host that we got in
pscsi_configure_device(). In VIRTUAL_HOST mode it is associated with
the dev_virt, not the hba_virt.

Signed-off-by: Andy Grover <agrover@redhat.com>
Cc: stable@vger.kernel.org # 2.6.38+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_pscsi.c

@@ -521,6 +521,7 @@ static int pscsi_configure_device(struct se_device *dev)
 					" pdv_host_id: %d\n", pdv->pdv_host_id);
 				return -EINVAL;
 			}
+			pdv->pdv_lld_host = sh;
 		}
 	} else {
 		if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
@@ -603,6 +604,8 @@ static void pscsi_free_device(struct se_device *dev)
 		if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
 		    (phv->phv_lld_host != NULL))
 			scsi_host_put(phv->phv_lld_host);
+		else if (pdv->pdv_lld_host)
+			scsi_host_put(pdv->pdv_lld_host);
 
 		if ((sd->type == TYPE_DISK) || (sd->type == TYPE_ROM))
 			scsi_device_put(sd);

drivers/target/target_core_pscsi.h

@@ -45,6 +45,7 @@ struct pscsi_dev_virt {
 	int	pdv_lun_id;
 	struct block_device *pdv_bd;
 	struct scsi_device *pdv_sd;
+	struct Scsi_Host *pdv_lld_host;
 } ____cacheline_aligned;
 
 typedef enum phv_modes {