linux/arch/x86/xen/pci-swiotlb-xen.c
Konrad Rzeszutek Wilk bbbe57386e pci-swiotlb-xen: Add glue code to setup dma_ops utilizing xen_swiotlb_*
functions.

We add the glue code that sets up a dma_ops structure with the
xen_swiotlb_* functions. The code turns on xen_swiotlb flag
when it detects it is running under Xen and it is either
in privileged mode or the iommu=soft flag was passed in.

It also disables the bare-metal SWIOTLB if the Xen-SWIOTLB has
been enabled.

Note: The Xen-SWIOTLB is only built when CONFIG_XEN is enabled.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Albert Herranz <albert_herranz@yahoo.es>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
2010-07-27 11:51:02 -04:00

59 lines
1.6 KiB
C

/* Glue code to lib/swiotlb-xen.c */
#include <linux/dma-mapping.h>
#include <xen/swiotlb-xen.h>
#include <asm/xen/hypervisor.h>
#include <xen/xen.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
* irregardlesss.
*/
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;
}
}