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Diffstat (limited to 'arch/x86/xen/pci-swiotlb-xen.c')
-rw-r--r--arch/x86/xen/pci-swiotlb-xen.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c
new file mode 100644
index 000000000000..a013ec9d0c54
--- /dev/null
+++ b/arch/x86/xen/pci-swiotlb-xen.c
@@ -0,0 +1,58 @@
+/* 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;
+ }
+}