[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>

1 files changed, 14 insertions, 6 deletions

diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c
index f84084bba2f0..e8d0115a025a 100644
--- a/drivers/scsi/libsas/sas_expander.c
+++ b/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: