iommu/tegra-smmu: Extract tegra_smmu_pte_get_use()
Extract the use count reference accounting into a separate function and
separate it from allocating the PTE.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[treding@nvidia.com: extract and write commit message]
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 27d31f6..74ad1f4 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -522,7 +522,7 @@
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;
@@ -563,13 +563,14 @@
*dmap = smmu_pde_to_dma(pd[pde]);
}
- pt = tegra_smmu_pte_offset(as->pts[pde], iova);
+ return tegra_smmu_pte_offset(as->pts[pde], iova);
+}
- /* Keep track of entries in this page table. */
- if (*pt == 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 pt;
+ as->count[pd_index]++;
}
static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
@@ -630,6 +631,10 @@
if (!pte)
return -ENOMEM;
+ /* If we aren't overwriting a pre-existing entry, increment use */
+ if (*pte == 0)
+ tegra_smmu_pte_get_use(as, iova);
+
tegra_smmu_set_pte(as, iova, pte, pte_dma,
__phys_to_pfn(paddr) | SMMU_PTE_ATTR);