[SCSI] libsas: Allow expander T-T attachments

Allow expander table-to-table attachments for
expanders that support it.
Signed-off-by: Luben Tuikov <ltuikov@yahoo.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/libsas/sas_expander.c

@@ -329,6 +329,7 @@ static void ex_assign_report_general(struct domain_device *dev,
 	dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
 	dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
 	dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
+	dev->ex_dev.t2t_supp = rg->t2t_supp;
 	dev->ex_dev.conf_route_table = rg->conf_route_table;
 	dev->ex_dev.configuring = rg->configuring;
 	memcpy(dev->ex_dev.enclosure_logical_id, rg->enclosure_logical_id, 8);
@@ -1133,15 +1134,17 @@ static void sas_print_parent_topology_bug(struct domain_device *child,
 	};
 	struct domain_device *parent = child->parent;
 
-	sas_printk("%s ex %016llx phy 0x%x <--> %s ex %016llx phy 0x%x "
-		   "has %c:%c routing link!\n",
+	sas_printk("%s ex %016llx (T2T supp:%d) phy 0x%x <--> %s ex %016llx "
+		   "(T2T supp:%d) phy 0x%x has %c:%c routing link!\n",
 
 		   ex_type[parent->dev_type],
 		   SAS_ADDR(parent->sas_addr),
+		   parent->ex_dev.t2t_supp,
 		   parent_phy->phy_id,
 
 		   ex_type[child->dev_type],
 		   SAS_ADDR(child->sas_addr),
+		   child->ex_dev.t2t_supp,
 		   child_phy->phy_id,
 
 		   ra_char[parent_phy->routing_attr],
@@ -1238,10 +1241,15 @@ static int sas_check_parent_topology(struct domain_device *child)
 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
 					res = -ENODEV;
 				}
-			} else if (parent_phy->routing_attr == TABLE_ROUTING &&
-				   child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
-				sas_print_parent_topology_bug(child, parent_phy, child_phy);
-				res = -ENODEV;
+			} else if (parent_phy->routing_attr == TABLE_ROUTING) {
+				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING ||
+				    (child_phy->routing_attr == TABLE_ROUTING &&
+				     child_ex->t2t_supp && parent_ex->t2t_supp)) {
+					/* All good */;
+				} else {
+					sas_print_parent_topology_bug(child, parent_phy, child_phy);
+					res = -ENODEV;
+				}
 			}
 			break;
 		case FANOUT_DEV:

include/scsi/libsas.h

@@ -142,8 +142,11 @@ struct expander_device {
 	u16    ex_change_count;
 	u16    max_route_indexes;
 	u8     num_phys;
+
+	u8     t2t_supp:1;
 	u8     configuring:1;
 	u8     conf_route_table:1;
+
 	u8     enclosure_logical_id[8];
 
 	struct ex_phy *ex_phy;

include/scsi/sas.h

@@ -349,7 +349,12 @@ struct report_general_resp {
 
 	u8      conf_route_table:1;
 	u8      configuring:1;
-	u8      _r_b:6;
+	u8	config_others:1;
+	u8	orej_retry_supp:1;
+	u8	stp_cont_awt:1;
+	u8	self_config:1;
+	u8	zone_config:1;
+	u8	t2t_supp:1;
 
 	u8      _r_c;
 
@@ -536,7 +541,12 @@ struct report_general_resp {
 	u8      _r_a;
 	u8      num_phys;
 
-	u8      _r_b:6;
+	u8	t2t_supp:1;
+	u8	zone_config:1;
+	u8	self_config:1;
+	u8	stp_cont_awt:1;
+	u8	orej_retry_supp:1;
+	u8	config_others:1;
 	u8      configuring:1;
 	u8      conf_route_table:1;