iommu/exynos: add missing cache flush for removed page table entries

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.

Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 233f382..e3be3e5 100644 (file)
--- 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;