WSL2-Linux-Kernel/arch/x86/xen/pci-swiotlb-xen.c

68 строки
1.8 KiB
C

/* 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>
int xen_swiotlb __read_mostly;
static struct dma_map_ops xen_swiotlb_dma_ops = {
.mapping_error = xen_swiotlb_dma_mapping_error,
.alloc_coherent = xen_swiotlb_alloc_coherent,
.free_coherent = 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 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_pv_domain()))
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. */
if (xen_pv_domain())
swiotlb = 0;
return xen_swiotlb;
}
void __init pci_xen_swiotlb_init(void)
{
if (xen_swiotlb) {
xen_swiotlb_init(1);
dma_ops = &xen_swiotlb_dma_ops;
/* Make sure ACS will be enabled */
pci_request_acs();
}
}
IOMMU_INIT_FINISH(pci_xen_swiotlb_detect,
0,
pci_xen_swiotlb_init,
0);