[PATCH 5/7] iommu/s390: support iova_to_phys for additional table regions

[Matthew Rosato <mjrosato@linux.ibm.com>]

The origin_type of the dma_table is used to determine how many table
levels must be traversed for the translation.

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
---
 drivers/iommu/s390-iommu.c | 42 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 41 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
index 5782f329cae9..cea528bf61db 100644
--- a/drivers/iommu/s390-iommu.c
+++ b/drivers/iommu/s390-iommu.c
@@ -744,6 +744,43 @@ static int s390_iommu_map_pages(struct iommu_domain *domain,
 	return rc;
 }
 
+static unsigned long *get_rto_from_iova(struct s390_domain *domain,
+					dma_addr_t iova)
+{
+	unsigned long *rfo, *rso, *rto;
+	unsigned long rfe, rse;
+	unsigned int rfx, rsx;
+
+	switch (domain->origin_type) {
+	case ZPCI_TABLE_TYPE_RFX:
+		rfo = domain->dma_table;
+		goto itp_rf;
+	case ZPCI_TABLE_TYPE_RSX:
+		rso = domain->dma_table;
+		goto itp_rs;
+	case ZPCI_TABLE_TYPE_RTX:
+		return domain->dma_table;
+	default:
+		return NULL;
+	}
+
+itp_rf:
+	rfx = calc_rfx(iova);
+	rfe = READ_ONCE(rfo[rfx]);
+	if (!reg_entry_isvalid(rfe))
+		return NULL;
+	rso = get_rf_rso(rfe);
+
+itp_rs:
+	rsx = calc_rsx(iova);
+	rse = READ_ONCE(rso[rsx]);
+	if (!reg_entry_isvalid(rse))
+		return NULL;
+	rto = get_rs_rto(rse);
+
+	return rto;
+}
+
 static phys_addr_t s390_iommu_iova_to_phys(struct iommu_domain *domain,
 					   dma_addr_t iova)
 {
@@ -757,10 +794,13 @@ static phys_addr_t s390_iommu_iova_to_phys(struct iommu_domain *domain,
 	    iova > domain->geometry.aperture_end)
 		return 0;
 
+	rto = get_rto_from_iova(s390_domain, iova);
+	if (!rto)
+		return 0;
+
 	rtx = calc_rtx(iova);
 	sx = calc_sx(iova);
 	px = calc_px(iova);
-	rto = s390_domain->dma_table;
 
 	rte = READ_ONCE(rto[rtx]);
 	if (reg_entry_isvalid(rte)) {
-- 
2.47.0