[SRU][Bionic][PATCH 1/2] vfio/spapr: Use IOMMU pageshift rather than pagesize

Joseph Salisbury joseph.salisbury at canonical.com
Fri Aug 31 13:55:19 UTC 2018

From: Alexey Kardashevskiy <aik at ozlabs.ru>

BugLink: https://bugs.launchpad.net/bugs/1785675

The size is always equal to 1 page so let's use this. Later on this will
be used for other checks which use page shifts to check the granularity
of access.

This should cause no behavioral change.

Cc: stable at vger.kernel.org # v4.12+
Reviewed-by: David Gibson <david at gibson.dropbear.id.au>
Acked-by: Alex Williamson <alex.williamson at redhat.com>
Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
(cherry picked from commit 1463edca6734d42ab4406fa2896e20b45478ea36)
Signed-off-by: Joseph Salisbury <joseph.salisbury at canonical.com>
 drivers/vfio/vfio_iommu_spapr_tce.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
index 759a5bd..2da5f05 100644
--- a/drivers/vfio/vfio_iommu_spapr_tce.c
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -457,13 +457,13 @@ static void tce_iommu_unuse_page(struct tce_container *container,
 static int tce_iommu_prereg_ua_to_hpa(struct tce_container *container,
-		unsigned long tce, unsigned long size,
+		unsigned long tce, unsigned long shift,
 		unsigned long *phpa, struct mm_iommu_table_group_mem_t **pmem)
 	long ret = 0;
 	struct mm_iommu_table_group_mem_t *mem;
-	mem = mm_iommu_lookup(container->mm, tce, size);
+	mem = mm_iommu_lookup(container->mm, tce, 1ULL << shift);
 	if (!mem)
 		return -EINVAL;
@@ -487,7 +487,7 @@ static void tce_iommu_unuse_page_v2(struct tce_container *container,
 	if (!pua)
-	ret = tce_iommu_prereg_ua_to_hpa(container, *pua, IOMMU_PAGE_SIZE(tbl),
+	ret = tce_iommu_prereg_ua_to_hpa(container, *pua, tbl->it_page_shift,
 			&hpa, &mem);
 	if (ret)
 		pr_debug("%s: tce %lx at #%lx was not cached, ret=%d\n",
@@ -611,7 +611,7 @@ static long tce_iommu_build_v2(struct tce_container *container,
 				entry + i);
 		ret = tce_iommu_prereg_ua_to_hpa(container,
-				tce, IOMMU_PAGE_SIZE(tbl), &hpa, &mem);
+				tce, tbl->it_page_shift, &hpa, &mem);
 		if (ret)

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