1 /* Glue code to lib/swiotlb-xen.c */
3 #include <linux/dma-mapping.h>
5 #include <xen/swiotlb-xen.h>
7 #include <asm/xen/hypervisor.h>
9 #include <asm/iommu_table.h>
12 #include <asm/xen/swiotlb-xen.h>
14 #include <asm/iommu.h>
17 #include <linux/export.h>
19 int xen_swiotlb __read_mostly;
21 static struct dma_map_ops xen_swiotlb_dma_ops = {
22 .alloc = xen_swiotlb_alloc_coherent,
23 .free = xen_swiotlb_free_coherent,
24 .sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu,
25 .sync_single_for_device = xen_swiotlb_sync_single_for_device,
26 .sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu,
27 .sync_sg_for_device = xen_swiotlb_sync_sg_for_device,
28 .map_sg = xen_swiotlb_map_sg_attrs,
29 .unmap_sg = xen_swiotlb_unmap_sg_attrs,
30 .map_page = xen_swiotlb_map_page,
31 .unmap_page = xen_swiotlb_unmap_page,
32 .dma_supported = xen_swiotlb_dma_supported,
36 * pci_xen_swiotlb_detect - set xen_swiotlb to 1 if necessary
38 * This returns non-zero if we are forced to use xen_swiotlb (by the boot
41 int __init pci_xen_swiotlb_detect(void)
47 /* If running as PV guest, either iommu=soft, or swiotlb=force will
48 * activate this IOMMU. If running as PV privileged, activate it
51 if ((xen_initial_domain() || swiotlb || swiotlb_force))
54 /* If we are running under Xen, we MUST disable the native SWIOTLB.
55 * Don't worry about swiotlb_force flag activating the native, as
56 * the 'swiotlb' flag is the only one turning it on. */
60 /* pci_swiotlb_detect_4gb turns on native SWIOTLB if no_iommu == 0
61 * (so no iommu=X command line over-writes).
62 * Considering that PV guests do not want the *native SWIOTLB* but
63 * only Xen SWIOTLB it is not useful to us so set no_iommu=1 here.
65 if (max_pfn > MAX_DMA32_PFN)
71 void __init pci_xen_swiotlb_init(void)
74 xen_swiotlb_init(1, true /* early */);
75 dma_ops = &xen_swiotlb_dma_ops;
78 /* Make sure ACS will be enabled */
84 int pci_xen_swiotlb_init_late(void)
91 rc = xen_swiotlb_init(1, false /* late */);
95 dma_ops = &xen_swiotlb_dma_ops;
97 /* Make sure ACS will be enabled */
103 EXPORT_SYMBOL_GPL(pci_xen_swiotlb_init_late);
105 IOMMU_INIT_FINISH(pci_xen_swiotlb_detect,
107 pci_xen_swiotlb_init,