2013-10-07 01:52:50

by Cho KyongHo

[permalink] [raw]
Subject: [PATCH v10 02/20] 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.

Reviewed-by: Tomasz Figa <[email protected]>
Tested-by: Grant Grundler <[email protected]>
Signed-off-by: Cho KyongHo <[email protected]>
---
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 4876d35..1c3a397 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -958,6 +958,7 @@ 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;
}
@@ -966,6 +967,7 @@ 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