x86/amd-iommu: Add function to complete a tlb flush

This patch adds a function to the AMD IOMMU driver which
completes all queued commands an all IOMMUs a specific
domain has devices attached on. This is required in a later
patch when per-domain flushing is implemented.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

arch/x86/kernel/amd_iommu.c

@@ -376,6 +376,22 @@ out:
 	return 0;
 }
 
+static void iommu_flush_complete(struct protection_domain *domain)
+{
+	int i;
+
+	for (i = 0; i < amd_iommus_present; ++i) {
+		if (!domain->dev_iommu[i])
+			continue;
+
+		/*
+		 * Devices of this domain are behind this IOMMU
+		 * We need to wait for completion of all commands.
+		 */
+		iommu_completion_wait(amd_iommus[i]);
+	}
+}
+
 /*
  * Command send function for invalidating a device table entry
  */
@@ -1758,7 +1774,7 @@ static dma_addr_t map_page(struct device *dev, struct page *page,
 	if (addr == DMA_ERROR_CODE)
 		goto out;
 
-	iommu_completion_wait(iommu);
+	iommu_flush_complete(domain);
 
 out:
 	spin_unlock_irqrestore(&domain->lock, flags);
@@ -1791,7 +1807,7 @@ static void unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
 
 	__unmap_single(iommu, domain->priv, dma_addr, size, dir);
 
-	iommu_completion_wait(iommu);
+	iommu_flush_complete(domain);
 
 	spin_unlock_irqrestore(&domain->lock, flags);
 }
@@ -1863,7 +1879,7 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
 			goto unmap;
 	}
 
-	iommu_completion_wait(iommu);
+	iommu_flush_complete(domain);
 
 out:
 	spin_unlock_irqrestore(&domain->lock, flags);
@@ -1914,7 +1930,7 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist,
 		s->dma_address = s->dma_length = 0;
 	}
 
-	iommu_completion_wait(iommu);
+	iommu_flush_complete(domain);
 
 	spin_unlock_irqrestore(&domain->lock, flags);
 }
@@ -1969,7 +1985,7 @@ static void *alloc_coherent(struct device *dev, size_t size,
 		goto out_free;
 	}
 
-	iommu_completion_wait(iommu);
+	iommu_flush_complete(domain);
 
 	spin_unlock_irqrestore(&domain->lock, flags);
 
@@ -2010,7 +2026,7 @@ static void free_coherent(struct device *dev, size_t size,
 
 	__unmap_single(iommu, domain->priv, dma_addr, size, DMA_BIDIRECTIONAL);
 
-	iommu_completion_wait(iommu);
+	iommu_flush_complete(domain);
 
 	spin_unlock_irqrestore(&domain->lock, flags);