iommu/tegra-smmu: Fix page tables in > 4 GiB memory
Page tables that reside in physical memory beyond the 4 GiB boundary are
currently not working properly. The reason is that when the physical
address for page directory entries is read, it gets truncated at 32 bits
and can cause crashes when passing that address to the DMA API.
Fix this by first casting the PDE value to a dma_addr_t and then using
the page frame number mask for the SMMU instance to mask out the invalid
bits, which are typically used for mapping attributes, etc.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index f51fe9b..965c097 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -159,9 +159,9 @@
return (addr & smmu->pfn_mask) == addr;
}
-static dma_addr_t smmu_pde_to_dma(u32 pde)
+static dma_addr_t smmu_pde_to_dma(struct tegra_smmu *smmu, u32 pde)
{
- return pde << 12;
+ return (dma_addr_t)(pde & smmu->pfn_mask) << 12;
}
static void smmu_flush_ptc_all(struct tegra_smmu *smmu)
@@ -554,6 +554,7 @@
dma_addr_t *dmap)
{
unsigned int pd_index = iova_pd_index(iova);
+ struct tegra_smmu *smmu = as->smmu;
struct page *pt_page;
u32 *pd;
@@ -562,7 +563,7 @@
return NULL;
pd = page_address(as->pd);
- *dmap = smmu_pde_to_dma(pd[pd_index]);
+ *dmap = smmu_pde_to_dma(smmu, pd[pd_index]);
return tegra_smmu_pte_offset(pt_page, iova);
}
@@ -604,7 +605,7 @@
} else {
u32 *pd = page_address(as->pd);
- *dmap = smmu_pde_to_dma(pd[pde]);
+ *dmap = smmu_pde_to_dma(smmu, pd[pde]);
}
return tegra_smmu_pte_offset(as->pts[pde], iova);
@@ -629,7 +630,7 @@
if (--as->count[pde] == 0) {
struct tegra_smmu *smmu = as->smmu;
u32 *pd = page_address(as->pd);
- dma_addr_t pte_dma = smmu_pde_to_dma(pd[pde]);
+ dma_addr_t pte_dma = smmu_pde_to_dma(smmu, pd[pde]);
tegra_smmu_set_pde(as, iova, 0);
