/* Glue code to lib/swiotlb-xen.c */ #include <linux/dma-mapping.h> #include <linux/pci.h> #include <xen/swiotlb-xen.h> #include <asm/xen/hypervisor.h> #include <xen/xen.h> #include <asm/iommu_table.h> #include <asm/xen/swiotlb-xen.h> #ifdef CONFIG_X86_64 #include <asm/iommu.h> #include <asm/dma.h> #endif #include <linux/export.h> int xen_swiotlb __read_mostly; static struct dma_map_ops xen_swiotlb_dma_ops = { .mapping_error = xen_swiotlb_dma_mapping_error, .alloc = xen_swiotlb_alloc_coherent, .free = xen_swiotlb_free_coherent, .sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu, .sync_single_for_device = xen_swiotlb_sync_single_for_device, .sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu, .sync_sg_for_device = xen_swiotlb_sync_sg_for_device, .map_sg = xen_swiotlb_map_sg_attrs, .unmap_sg = xen_swiotlb_unmap_sg_attrs, .map_page = xen_swiotlb_map_page, .unmap_page = xen_swiotlb_unmap_page, .dma_supported = xen_swiotlb_dma_supported, }; /* * pci_xen_swiotlb_detect - set xen_swiotlb to 1 if necessary * * This returns non-zero if we are forced to use xen_swiotlb (by the boot * option). */ int __init pci_xen_swiotlb_detect(void) { if (!xen_pv_domain()) return 0; /* If running as PV guest, either iommu=soft, or swiotlb=force will * activate this IOMMU. If running as PV privileged, activate it * irregardless. */ if ((xen_initial_domain() || swiotlb || swiotlb_force)) xen_swiotlb = 1; /* If we are running under Xen, we MUST disable the native SWIOTLB. * Don't worry about swiotlb_force flag activating the native, as * the 'swiotlb' flag is the only one turning it on. */ swiotlb = 0; #ifdef CONFIG_X86_64 /* pci_swiotlb_detect_4gb turns on native SWIOTLB if no_iommu == 0 * (so no iommu=X command line over-writes). * Considering that PV guests do not want the *native SWIOTLB* but * only Xen SWIOTLB it is not useful to us so set no_iommu=1 here. */ if (max_pfn > MAX_DMA32_PFN) no_iommu = 1; #endif return xen_swiotlb; } void __init pci_xen_swiotlb_init(void) { if (xen_swiotlb) { xen_swiotlb_init(1, true /* early */); dma_ops = &xen_swiotlb_dma_ops; #ifdef CONFIG_PCI /* Make sure ACS will be enabled */ pci_request_acs(); #endif } } int pci_xen_swiotlb_init_late(void) { int rc; if (xen_swiotlb) return 0; rc = xen_swiotlb_init(1, false /* late */); if (rc) return rc; dma_ops = &xen_swiotlb_dma_ops; #ifdef CONFIG_PCI /* Make sure ACS will be enabled */ pci_request_acs(); #endif return 0; } EXPORT_SYMBOL_GPL(pci_xen_swiotlb_init_late); IOMMU_INIT_FINISH(pci_xen_swiotlb_detect, NULL, pci_xen_swiotlb_init, NULL);