iommu/tegra-smmu: Use __GFP_ZERO to allocate zeroed pages
Rather than explicitly zeroing pages allocated via alloc_page(), add
__GFP_ZERO to the gfp mask to ask the allocator for zeroed pages.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index eb9f606..27d31f6 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -258,8 +258,6 @@
static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
{
struct tegra_smmu_as *as;
- unsigned int i;
- uint32_t *pd;
if (type != IOMMU_DOMAIN_UNMANAGED)
return NULL;
@@ -270,7 +268,7 @@
as->attr = SMMU_PD_READABLE | SMMU_PD_WRITABLE | SMMU_PD_NONSECURE;
- as->pd = alloc_page(GFP_KERNEL | __GFP_DMA);
+ as->pd = alloc_page(GFP_KERNEL | __GFP_DMA | __GFP_ZERO);
if (!as->pd) {
kfree(as);
return NULL;
@@ -291,12 +289,6 @@
return NULL;
}
- /* clear PDEs */
- pd = page_address(as->pd);
-
- for (i = 0; i < SMMU_NUM_PDE; i++)
- pd[i] = 0;
-
/* setup aperture */
as->domain.geometry.aperture_start = 0;
as->domain.geometry.aperture_end = 0xffffffff;
@@ -533,21 +525,15 @@
u32 *pd = page_address(as->pd), *pt;
unsigned int pde = iova_pd_index(iova);
struct tegra_smmu *smmu = as->smmu;
- unsigned int i;
if (!as->pts[pde]) {
struct page *page;
dma_addr_t dma;
- page = alloc_page(GFP_KERNEL | __GFP_DMA);
+ page = alloc_page(GFP_KERNEL | __GFP_DMA | __GFP_ZERO);
if (!page)
return NULL;
- pt = page_address(page);
-
- for (i = 0; i < SMMU_NUM_PTE; i++)
- pt[i] = 0;
-
dma = dma_map_page(smmu->dev, page, 0, SMMU_SIZE_PT,
DMA_TO_DEVICE);
if (dma_mapping_error(smmu->dev, dma)) {