1 files changed, 44 insertions, 56 deletions

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 7cca030a508e..b9d058c27568 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -163,38 +163,6 @@ static phys_addr_t root_entry_uctp(struct root_entry *re)
 	return re->hi & VTD_PAGE_MASK;
 }
 
-static inline void context_clear_pasid_enable(struct context_entry *context)
-{
-	context->lo &= ~(1ULL << 11);
-}
-
-static inline bool context_pasid_enabled(struct context_entry *context)
-{
-	return !!(context->lo & (1ULL << 11));
-}
-
-static inline void context_set_copied(struct context_entry *context)
-{
-	context->hi |= (1ull << 3);
-}
-
-static inline bool context_copied(struct context_entry *context)
-{
-	return !!(context->hi & (1ULL << 3));
-}
-
-static inline bool __context_present(struct context_entry *context)
-{
-	return (context->lo & 1);
-}
-
-bool context_present(struct context_entry *context)
-{
-	return context_pasid_enabled(context) ?
-	     __context_present(context) :
-	     __context_present(context) && !context_copied(context);
-}
-
 static inline void context_set_present(struct context_entry *context)
 {
 	context->lo |= 1;
@@ -242,6 +210,26 @@ static inline void context_clear_entry(struct context_entry *context)
 	context->hi = 0;
 }
 
+static inline bool context_copied(struct intel_iommu *iommu, u8 bus, u8 devfn)
+{
+	if (!iommu->copied_tables)
+		return false;
+
+	return test_bit(((long)bus << 8) | devfn, iommu->copied_tables);
+}
+
+static inline void
+set_context_copied(struct intel_iommu *iommu, u8 bus, u8 devfn)
+{
+	set_bit(((long)bus << 8) | devfn, iommu->copied_tables);
+}
+
+static inline void
+clear_context_copied(struct intel_iommu *iommu, u8 bus, u8 devfn)
+{
+	clear_bit(((long)bus << 8) | devfn, iommu->copied_tables);
+}
+
 /*
  * This domain is a statically identity mapping domain.
  *	1. This domain creats a static 1:1 mapping to all usable memory.
@@ -578,6 +566,13 @@ struct context_entry *iommu_context_addr(struct intel_iommu *iommu, u8 bus,
 	struct context_entry *context;
 	u64 *entry;
 
+	/*
+	 * Except that the caller requested to allocate a new entry,
+	 * returning a copied context entry makes no sense.
+	 */
+	if (!alloc && context_copied(iommu, bus, devfn))
+		return NULL;
+
 	entry = &root->lo;
 	if (sm_supported(iommu)) {
 		if (devfn >= 0x80) {
@@ -1688,6 +1683,11 @@ static void free_dmar_iommu(struct intel_iommu *iommu)
 		iommu->domain_ids = NULL;
 	}
 
+	if (iommu->copied_tables) {
+		bitmap_free(iommu->copied_tables);
+		iommu->copied_tables = NULL;
+	}
+
 	/* free context mapping */
 	free_context_table(iommu);
 
@@ -1913,7 +1913,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain,
 		goto out_unlock;
 
 	ret = 0;
-	if (context_present(context))
+	if (context_present(context) && !context_copied(iommu, bus, devfn))
 		goto out_unlock;
 
 	/*
@@ -1925,7 +1925,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain,
 	 * in-flight DMA will exist, and we don't need to worry anymore
 	 * hereafter.
 	 */
-	if (context_copied(context)) {
+	if (context_copied(iommu, bus, devfn)) {
 		u16 did_old = context_domain_id(context);
 
 		if (did_old < cap_ndoms(iommu->cap)) {
@@ -1936,6 +1936,8 @@ static int domain_context_mapping_one(struct dmar_domain *domain,
 			iommu->flush.flush_iotlb(iommu, did_old, 0, 0,
 						 DMA_TLB_DSI_FLUSH);
 		}
+
+		clear_context_copied(iommu, bus, devfn);
 	}
 
 	context_clear_entry(context);
@@ -2684,32 +2686,14 @@ static int copy_context_table(struct intel_iommu *iommu,
 		/* Now copy the context entry */
 		memcpy(&ce, old_ce + idx, sizeof(ce));
 
-		if (!__context_present(&ce))
+		if (!context_present(&ce))
 			continue;
 
 		did = context_domain_id(&ce);
 		if (did >= 0 && did < cap_ndoms(iommu->cap))
 			set_bit(did, iommu->domain_ids);
 
-		/*
-		 * We need a marker for copied context entries. This
-		 * marker needs to work for the old format as well as
-		 * for extended context entries.
-		 *
-		 * Bit 67 of the context entry is used. In the old
-		 * format this bit is available to software, in the
-		 * extended format it is the PGE bit, but PGE is ignored
-		 * by HW if PASIDs are disabled (and thus still
-		 * available).
-		 *
-		 * So disable PASIDs first and then mark the entry
-		 * copied. This means that we don't copy PASID
-		 * translations from the old kernel, but this is fine as
-		 * faults there are not fatal.
-		 */
-		context_clear_pasid_enable(&ce);
-		context_set_copied(&ce);
-
+		set_context_copied(iommu, bus, devfn);
 		new_ce[idx] = ce;
 	}
 
@@ -2735,8 +2719,8 @@ static int copy_translation_tables(struct intel_iommu *iommu)
 	bool new_ext, ext;
 
 	rtaddr_reg = dmar_readq(iommu->reg + DMAR_RTADDR_REG);
-	ext        = !!(rtaddr_reg & DMA_RTADDR_RTT);
-	new_ext    = !!ecap_ecs(iommu->ecap);
+	ext        = !!(rtaddr_reg & DMA_RTADDR_SMT);
+	new_ext    = !!sm_supported(iommu);
 
 	/*
 	 * The RTT bit can only be changed when translation is disabled,
@@ -2747,6 +2731,10 @@ static int copy_translation_tables(struct intel_iommu *iommu)
 	if (new_ext != ext)
 		return -EINVAL;
 
+	iommu->copied_tables = bitmap_zalloc(BIT_ULL(16), GFP_KERNEL);
+	if (!iommu->copied_tables)
+		return -ENOMEM;
+
 	old_rt_phys = rtaddr_reg & VTD_PAGE_MASK;
 	if (!old_rt_phys)
 		return -EINVAL;