[PATCH v9 02/16] iommu/exynos: add missing cache flush for removed page table entries

[Cho KyongHo <pullip.cho-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>]

This commit adds cache flush for removed small and large page entries
in exynos_iommu_unmap(). Missing cache flush of removed page table
entries can cause missing page fault interrupt when a master IP
accesses an unmapped area.

Tested-by: Grant Grundler <grundler-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Signed-off-by: Cho KyongHo <pullip.cho-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
---
 drivers/iommu/exynos-iommu.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 233f382..d545a25 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -1002,6 +1002,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
 	if (lv2ent_small(ent)) {
 		*ent = 0;
 		size = SPAGE_SIZE;
+		pgtable_flush(ent, ent + 1);
 		priv->lv2entcnt[lv1ent_offset(iova)] += 1;
 		goto done;
 	}
@@ -1010,6 +1011,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
 	BUG_ON(size < LPAGE_SIZE);
 
 	memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
+	pgtable_flush(ent, ent + SPAGES_PER_LPAGE);
 
 	size = LPAGE_SIZE;
 	priv->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;
-- 
1.7.2.5