intel-iommu: Use correct domain ID when caching mode is enabled

In caching-mode mappings of pages (changes from non-present to present)
require invalidation.
Currently, this IOTLB flush is performed with domain ID of zero.
This is not according to the VT-d spec and causes big problems for
emulating software.
This patch uses the correct domain ID in IOTLB flushes.
Device IOTLB invalidation is performed only on present to non-present
changes. This decision is now based on explicit parameter instead of
zero domain-ID.

Signed-off-by: Nadav Amit <nadav.amit@gmail.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 341da41..1880ee0 100644 (file)
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1064,7 +1064,7 @@ static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
 }
 
 static void iommu_flush_iotlb_psi(struct intel_iommu *iommu, u16 did,
-                                 unsigned long pfn, unsigned int pages)
+                                 unsigned long pfn, unsigned int pages, int map)
 {
        unsigned int mask = ilog2(__roundup_pow_of_two(pages));
        uint64_t addr = (uint64_t)pfn << VTD_PAGE_SHIFT;
@@ -1085,10 +1085,10 @@ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu, u16 did,
                                                DMA_TLB_PSI_FLUSH);
 
        /*
-        * In caching mode, domain ID 0 is reserved for non-present to present
-        * mapping flush. Device IOTLB doesn't need to be flushed in this case.
+        * In caching mode, changes of pages from non-present to present require
+        * flush. However, device IOTLB doesn't need to be flushed in this case.
         */
-       if (!cap_caching_mode(iommu->cap) || did)
+       if (!cap_caching_mode(iommu->cap) || !map)
                iommu_flush_dev_iotlb(iommu->domains[did], addr, mask);
 }
 
@@ -1544,7 +1544,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain, int segment,
                                           (((u16)bus) << 8) | devfn,
                                           DMA_CCMD_MASK_NOBIT,
                                           DMA_CCMD_DEVICE_INVL);
-               iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_DSI_FLUSH);
+               iommu->flush.flush_iotlb(iommu, domain->id, 0, 0, DMA_TLB_DSI_FLUSH);
        } else {
                iommu_flush_write_buffer(iommu);
        }
@@ -2607,7 +2607,7 @@ static dma_addr_t __intel_map_single(struct device *hwdev, phys_addr_t paddr,
 
        /* it's a non-present to present mapping. Only flush if caching mode */
        if (cap_caching_mode(iommu->cap))
-               iommu_flush_iotlb_psi(iommu, 0, mm_to_dma_pfn(iova->pfn_lo), size);
+               iommu_flush_iotlb_psi(iommu, domain->id, mm_to_dma_pfn(iova->pfn_lo), size, 1);
        else
                iommu_flush_write_buffer(iommu);
 
@@ -2736,7 +2736,7 @@ static void intel_unmap_page(struct device *dev, dma_addr_t dev_addr,
 
        if (intel_iommu_strict) {
                iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
-                                     last_pfn - start_pfn + 1);
+                                     last_pfn - start_pfn + 1, 0);
                /* free iova */
                __free_iova(&domain->iovad, iova);
        } else {
@@ -2826,7 +2826,7 @@ static void intel_unmap_sg(struct device *hwdev, struct scatterlist *sglist,
 
        if (intel_iommu_strict) {
                iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
-                                     last_pfn - start_pfn + 1);
+                                     last_pfn - start_pfn + 1, 0);
                /* free iova */
                __free_iova(&domain->iovad, iova);
        } else {
@@ -2913,7 +2913,7 @@ static int intel_map_sg(struct device *hwdev, struct scatterlist *sglist, int ne
 
        /* it's a non-present to present mapping. Only flush if caching mode */
        if (cap_caching_mode(iommu->cap))
-               iommu_flush_iotlb_psi(iommu, 0, start_vpfn, size);
+               iommu_flush_iotlb_psi(iommu, domain->id, start_vpfn, size, 1);
        else
                iommu_flush_write_buffer(iommu);