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 "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);