intel-iommu: VT-d page table to support snooping control bit
The user can request to enable snooping control through VT-d page table.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 3778ab1..a0ba568 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -164,7 +164,8 @@
* 1: writable
* 2-6: reserved
* 7: super page
- * 8-11: available
+ * 8-10: available
+ * 11: snoop behavior
* 12-63: Host physcial address
*/
struct dma_pte {
@@ -186,6 +187,11 @@
pte->val |= DMA_PTE_WRITE;
}
+static inline void dma_set_pte_snp(struct dma_pte *pte)
+{
+ pte->val |= DMA_PTE_SNP;
+}
+
static inline void dma_set_pte_prot(struct dma_pte *pte, unsigned long prot)
{
pte->val = (pte->val & ~3) | (prot & 3);
@@ -1685,6 +1691,8 @@
BUG_ON(dma_pte_addr(pte));
dma_set_pte_addr(pte, start_pfn << VTD_PAGE_SHIFT);
dma_set_pte_prot(pte, prot);
+ if (prot & DMA_PTE_SNP)
+ dma_set_pte_snp(pte);
domain_flush_cache(domain, pte, sizeof(*pte));
start_pfn++;
index++;
@@ -3105,6 +3113,8 @@
prot |= DMA_PTE_READ;
if (iommu_prot & IOMMU_WRITE)
prot |= DMA_PTE_WRITE;
+ if ((iommu_prot & IOMMU_CACHE) && dmar_domain->iommu_snooping)
+ prot |= DMA_PTE_SNP;
max_addr = (iova & VTD_PAGE_MASK) + VTD_PAGE_ALIGN(size);
if (dmar_domain->max_addr < max_addr) {
diff --git a/include/linux/dma_remapping.h b/include/linux/dma_remapping.h
index af1dab4..1a455f1 100644
--- a/include/linux/dma_remapping.h
+++ b/include/linux/dma_remapping.h
@@ -11,6 +11,7 @@
#define DMA_PTE_READ (1)
#define DMA_PTE_WRITE (2)
+#define DMA_PTE_SNP (1 << 11)
struct intel_iommu;
struct dmar_domain;
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 0cf3a4e..3af4ffd 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -21,6 +21,7 @@
#define IOMMU_READ (1)
#define IOMMU_WRITE (2)
+#define IOMMU_CACHE (4) /* DMA cache coherency */
struct device;