xref: /openbmc/linux/arch/x86/xen/mmu.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/pfn.h>
4 #include <asm/xen/page.h>
5 #include <asm/xen/hypercall.h>
6 #include <xen/interface/memory.h>
7 
8 #include "multicalls.h"
9 #include "mmu.h"
10 
11 unsigned long arbitrary_virt_to_mfn(void *vaddr)
12 {
13 	xmaddr_t maddr = arbitrary_virt_to_machine(vaddr);
14 
15 	return PFN_DOWN(maddr.maddr);
16 }
17 
18 xmaddr_t arbitrary_virt_to_machine(void *vaddr)
19 {
20 	unsigned long address = (unsigned long)vaddr;
21 	unsigned int level;
22 	pte_t *pte;
23 	unsigned offset;
24 
25 	/*
26 	 * if the PFN is in the linear mapped vaddr range, we can just use
27 	 * the (quick) virt_to_machine() p2m lookup
28 	 */
29 	if (virt_addr_valid(vaddr))
30 		return virt_to_machine(vaddr);
31 
32 	/* otherwise we have to do a (slower) full page-table walk */
33 
34 	pte = lookup_address(address, &level);
35 	BUG_ON(pte == NULL);
36 	offset = address & ~PAGE_MASK;
37 	return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset);
38 }
39 EXPORT_SYMBOL_GPL(arbitrary_virt_to_machine);
40 
41 /* Returns: 0 success */
42 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
43 			       int nr, struct page **pages)
44 {
45 	if (xen_feature(XENFEAT_auto_translated_physmap))
46 		return xen_xlate_unmap_gfn_range(vma, nr, pages);
47 
48 	if (!pages)
49 		return 0;
50 
51 	return -EINVAL;
52 }
53 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);
54