arch/x86/xen/mmu.c

   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 "xen-ops.h"
   9
  10 unsigned long arbitrary_virt_to_mfn(void *vaddr)
  11 {
  12         xmaddr_t maddr = arbitrary_virt_to_machine(vaddr);
  13
  14         return PFN_DOWN(maddr.maddr);
  15 }
  16
  17 xmaddr_t arbitrary_virt_to_machine(void *vaddr)
  18 {
  19         unsigned long address = (unsigned long)vaddr;
  20         unsigned int level;
  21         pte_t *pte;
  22         unsigned offset;
  23
  24         /*
  25          * if the PFN is in the linear mapped vaddr range, we can just use
  26          * the (quick) virt_to_machine() p2m lookup
  27          */
  28         if (virt_addr_valid(vaddr))
  29                 return virt_to_machine(vaddr);
  30
  31         /* otherwise we have to do a (slower) full page-table walk */
  32
  33         pte = lookup_address(address, &level);
  34         BUG_ON(pte == NULL);
  35         offset = address & ~PAGE_MASK;
  36         return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset);
  37 }
  38 EXPORT_SYMBOL_GPL(arbitrary_virt_to_machine);
  39
  40 /* Returns: 0 success */
  41 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
  42                                int nr, struct page **pages)
  43 {
  44         if (xen_feature(XENFEAT_auto_translated_physmap))
  45                 return xen_xlate_unmap_gfn_range(vma, nr, pages);
  46
  47         if (!pages)
  48                 return 0;
  49
  50         return -EINVAL;
  51 }
  52 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);