[PATCH 16/18] iommu: tegra-smmu: get_use
Russell King
rmk+kernel at arm.linux.org.uk
Mon Jul 27 05:30:07 PDT 2015
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
drivers/iommu/tegra-smmu.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index bc179c759805..8bf38b95cdd5 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -524,7 +524,7 @@ static u32 *tegra_smmu_pte_lookup(struct tegra_smmu_as *as, unsigned long iova,
static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
dma_addr_t *dmap)
{
- u32 *pd = page_address(as->pd), *pt;
+ u32 *pd = page_address(as->pd);
unsigned int pde = iova_pd_index(iova);
struct tegra_smmu *smmu = as->smmu;
@@ -565,13 +565,14 @@ static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
*dmap = smmu_pde_to_dma(pd[pde]);
}
- pt = page_address(as->pts[pde]);
+ return tegra_smmu_pte_offset(as->pts[pde], iova);
+}
- /* Keep track of entries in this page table. */
- if (pt[iova_pt_index(iova)] == 0)
- as->count[pde]++;
+static void tegra_smmu_pte_get_use(struct tegra_smmu_as *as, unsigned long iova)
+{
+ unsigned int pd_index = iova_pd_index(iova);
- return tegra_smmu_pte_offset(as->pts[pde], iova);
+ as->count[pd_index]++;
}
static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
@@ -632,6 +633,10 @@ static int tegra_smmu_map(struct iommu_domain *domain, unsigned long iova,
if (!pte)
return -ENOMEM;
+ /* If we aren't overwriting a pre-existing entry, increment use */
+ if (!*pte)
+ tegra_smmu_pte_get_use(as, iova);
+
tegra_smmu_set_pte(as, iova, pte, pte_dma,
__phys_to_pfn(paddr) | SMMU_PTE_ATTR);
--
2.1.0
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