diff --git a/arch/x86_64/kernel/pci-swiotlb.c b/arch/x86_64/kernel/pci-swiotlb.c index ebdb77fe2057..6a55f87ba97f 100644 --- a/arch/x86_64/kernel/pci-swiotlb.c +++ b/arch/x86_64/kernel/pci-swiotlb.c @@ -31,9 +31,10 @@ struct dma_mapping_ops swiotlb_dma_ops = { void pci_swiotlb_init(void) { /* don't initialize swiotlb if iommu=off (no_iommu=1) */ - if (!iommu_detected && !no_iommu && - (end_pfn > MAX_DMA32_PFN || force_iommu)) + if (!iommu_detected && !no_iommu && end_pfn > MAX_DMA32_PFN) swiotlb = 1; + if (swiotlb_force) + swiotlb = 1; if (swiotlb) { printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n"); swiotlb_init(); diff --git a/include/asm-x86_64/swiotlb.h b/include/asm-x86_64/swiotlb.h index 5f9a01805821..ba94ab3d2673 100644 --- a/include/asm-x86_64/swiotlb.h +++ b/include/asm-x86_64/swiotlb.h @@ -42,6 +42,8 @@ extern void swiotlb_free_coherent (struct device *hwdev, size_t size, extern int swiotlb_dma_supported(struct device *hwdev, u64 mask); extern void swiotlb_init(void); +extern int swiotlb_force; + #ifdef CONFIG_SWIOTLB extern int swiotlb; #else