iommu/vt-d: Remove unnecassary qi clflushes

According to the manual: "Hardware access to ...  invalidation queue ...
are always coherent."

Remove unnecassary clflushes accordingly.

Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 2eff7b6c6c98f673864e101531656b9ddc7574fd..1344e29acd861a43490851c7f3eeb3717c924115 100644 (file)
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -1167,8 +1167,6 @@ static int qi_check_fault(struct intel_iommu *iommu, int index)
                                (unsigned long long)qi->desc[index].high);
                        memcpy(&qi->desc[index], &qi->desc[wait_index],
                                        sizeof(struct qi_desc));
-                       __iommu_flush_cache(iommu, &qi->desc[index],
-                                       sizeof(struct qi_desc));
                        writel(DMA_FSTS_IQE, iommu->reg + DMAR_FSTS_REG);
                        return -EINVAL;
                }
@@ -1243,9 +1241,6 @@ restart:
 
        hw[wait_index] = wait_desc;
 
-       __iommu_flush_cache(iommu, &hw[index], sizeof(struct qi_desc));
-       __iommu_flush_cache(iommu, &hw[wait_index], sizeof(struct qi_desc));
-
        qi->free_head = (qi->free_head + 2) % QI_LENGTH;
        qi->free_cnt -= 2;