1 files changed, 14 insertions, 4 deletions

diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
index aaa6b7839f1e..e3c0a66b9e77 100644
--- a/arch/x86/kernel/pci-swiotlb.c
+++ b/arch/x86/kernel/pci-swiotlb.c
@@ -42,18 +42,28 @@ static struct dma_map_ops swiotlb_dma_ops = {
         .dma_supported = NULL,
 };
 
-void __init pci_swiotlb_init(void)
+/*
+ * pci_swiotlb_init - initialize swiotlb if necessary
+ *
+ * This returns non-zero if we are forced to use swiotlb (by the boot
+ * option).
+ */
+int __init pci_swiotlb_init(void)
 {
+        int use_swiotlb = swiotlb | swiotlb_force;
+
         /* don't initialize swiotlb if iommu=off (no_iommu=1) */
 #ifdef CONFIG_X86_64
-        if ((!iommu_detected && !no_iommu && max_pfn > MAX_DMA32_PFN))
+        if (!no_iommu && max_pfn > MAX_DMA32_PFN)
                 swiotlb = 1;
 #endif
         if (swiotlb_force)
                 swiotlb = 1;
+
         if (swiotlb) {
-                printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n");
-                swiotlb_init();
+                swiotlb_init(0);
                 dma_ops = &swiotlb_dma_ops;
         }
+
+        return use_swiotlb;
 }