1 files changed, 53 insertions, 0 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
new file mode 100644
index 000000000..60e9c37fd
--- /dev/null
+++ b/arch/x86/xen/mmu.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/pfn.h>
+#include <asm/xen/page.h>
+#include <asm/xen/hypercall.h>
+#include <xen/interface/memory.h>
+
+#include "multicalls.h"
+#include "mmu.h"
+
+unsigned long arbitrary_virt_to_mfn(void *vaddr)
+{
+	xmaddr_t maddr = arbitrary_virt_to_machine(vaddr);
+
+	return PFN_DOWN(maddr.maddr);
+}
+
+xmaddr_t arbitrary_virt_to_machine(void *vaddr)
+{
+	unsigned long address = (unsigned long)vaddr;
+	unsigned int level;
+	pte_t *pte;
+	unsigned offset;
+
+	/*
+	 * if the PFN is in the linear mapped vaddr range, we can just use
+	 * the (quick) virt_to_machine() p2m lookup
+	 */
+	if (virt_addr_valid(vaddr))
+		return virt_to_machine(vaddr);
+
+	/* otherwise we have to do a (slower) full page-table walk */
+
+	pte = lookup_address(address, &level);
+	BUG_ON(pte == NULL);
+	offset = address & ~PAGE_MASK;
+	return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset);
+}
+EXPORT_SYMBOL_GPL(arbitrary_virt_to_machine);
+
+/* Returns: 0 success */
+int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
+			       int nr, struct page **pages)
+{
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		return xen_xlate_unmap_gfn_range(vma, nr, pages);
+
+	if (!pages)
+		return 0;
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);