iommu/s390: set appropriate IOTA region type

When registering the I/O Translation Anchor, use the current table type
stored in the s390_domain to set the appropriate region type
indication.  For the moment, the table type will always be stored as
region third.

Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20250411202433.181683-2-mjrosato@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Author: rosatomj

drivers/iommu/s390-iommu.c

@@ -31,6 +31,7 @@ struct s390_domain {
 	unsigned long		*dma_table;
 	spinlock_t		list_lock;
 	struct rcu_head		rcu;
+	u8			origin_type;
 };
 
 static struct iommu_domain blocking_domain;
@@ -345,6 +346,7 @@ static struct iommu_domain *s390_domain_alloc_paging(struct device *dev)
 	s390_domain->domain.geometry.force_aperture = true;
 	s390_domain->domain.geometry.aperture_start = 0;
 	s390_domain->domain.geometry.aperture_end = ZPCI_TABLE_SIZE_RT - 1;
+	s390_domain->origin_type = ZPCI_TABLE_TYPE_RTX;
 
 	spin_lock_init(&s390_domain->list_lock);
 	INIT_LIST_HEAD_RCU(&s390_domain->devices);
@@ -381,6 +383,21 @@ static void zdev_s390_domain_update(struct zpci_dev *zdev,
 	spin_unlock_irqrestore(&zdev->dom_lock, flags);
 }
 
+static u64 get_iota_region_flag(struct s390_domain *domain)
+{
+	switch (domain->origin_type) {
+	case ZPCI_TABLE_TYPE_RTX:
+		return ZPCI_IOTA_RTTO_FLAG;
+	case ZPCI_TABLE_TYPE_RSX:
+		return ZPCI_IOTA_RSTO_FLAG;
+	case ZPCI_TABLE_TYPE_RFX:
+		return ZPCI_IOTA_RFTO_FLAG;
+	default:
+		WARN_ONCE(1, "Invalid IOMMU table (%x)\n", domain->origin_type);
+		return 0;
+	}
+}
+
 static int s390_iommu_domain_reg_ioat(struct zpci_dev *zdev,
 				      struct iommu_domain *domain, u8 *status)
 {
@@ -399,7 +416,7 @@ static int s390_iommu_domain_reg_ioat(struct zpci_dev *zdev,
 	default:
 		s390_domain = to_s390_domain(domain);
 		iota = virt_to_phys(s390_domain->dma_table) |
-		       ZPCI_IOTA_RTTO_FLAG;
+		       get_iota_region_flag(s390_domain);
 		rc = zpci_register_ioat(zdev, 0, zdev->start_dma,
 					zdev->end_dma, iota, status);
 	}