[SCSI] libsas: use ->lldd_I_T_nexus_reset for ->eh_bus_reset_handler

sas_eh_bus_reset_handler() amounts to sas_phy_reset() without
notification of the reset to the lldd.  If this is triggered from
eh-cmnd recovery there may be sas_tasks for the lldd to terminate, so
->lldd_I_T_nexus_reset is warranted.

Cc: Xiangliang Yu <yuxiangl@marvell.com>
Cc: Luben Tuikov <ltuikov@yahoo.com>
Cc: Jack Wang <jack_wang@usish.com>
Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
[jacek: modify pm8001_I_T_nexus_reset to return -ENODEV]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/libsas/sas_scsi_host.c

@@ -576,25 +576,22 @@ int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
 	return FAILED;
 }
 
-/* Attempt to send a phy (bus) reset */
 int sas_eh_bus_reset_handler(struct scsi_cmnd *cmd)
 {
-	struct domain_device *dev = cmd_to_domain_dev(cmd);
-	struct sas_phy *phy = sas_get_local_phy(dev);
-	struct Scsi_Host *host = cmd->device->host;
 	int res;
+	struct Scsi_Host *host = cmd->device->host;
+	struct domain_device *dev = cmd_to_domain_dev(cmd);
+	struct sas_internal *i = to_sas_internal(host->transportt);
 
 	if (current != host->ehandler)
 		return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
 
-	res = sas_phy_reset(phy, 1);
-	if (res)
-		SAS_DPRINTK("Bus reset of %s failed 0x%x\n",
-			    kobject_name(&phy->dev.kobj),
-			    res);
-	sas_put_local_phy(phy);
+	if (!i->dft->lldd_I_T_nexus_reset)
+		return FAILED;
 
-	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
+	res = i->dft->lldd_I_T_nexus_reset(dev);
+	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
+	    res == -ENODEV)
 		return SUCCESS;
 
 	return FAILED;

drivers/scsi/pm8001/pm8001_sas.c

@@ -962,8 +962,9 @@ int pm8001_I_T_nexus_reset(struct domain_device *dev)
 	struct pm8001_device *pm8001_dev;
 	struct pm8001_hba_info *pm8001_ha;
 	struct sas_phy *phy;
+
 	if (!dev || !dev->lldd_dev)
-		return -1;
+		return -ENODEV;
 
 	pm8001_dev = dev->lldd_dev;
 	pm8001_ha = pm8001_find_ha_by_dev(dev);