mm/x86/pat: use the new follow_pfnmap API

Use the new API that can understand huge pfn mappings.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Peter Xu <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Alex Williamson <[email protected]>
Cc: Aneesh Kumar K.V <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Gavin Shan <[email protected]>
Cc: Gerald Schaefer <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Niklas Schnelle <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: xzpeter

arch/x86/mm/pat/memtype.c

@@ -951,23 +951,20 @@ static void free_pfn_range(u64 paddr, unsigned long size)
 static int follow_phys(struct vm_area_struct *vma, unsigned long *prot,
 		resource_size_t *phys)
 {
-	pte_t *ptep, pte;
-	spinlock_t *ptl;
+	struct follow_pfnmap_args args = { .vma = vma, .address = vma->vm_start };
 
-	if (follow_pte(vma, vma->vm_start, &ptep, &ptl))
+	if (follow_pfnmap_start(&args))
 		return -EINVAL;
 
-	pte = ptep_get(ptep);
-
 	/* Never return PFNs of anon folios in COW mappings. */
-	if (vm_normal_folio(vma, vma->vm_start, pte)) {
-		pte_unmap_unlock(ptep, ptl);
+	if (!args.special) {
+		follow_pfnmap_end(&args);
 		return -EINVAL;
 	}
 
-	*prot = pgprot_val(pte_pgprot(pte));
-	*phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT;
-	pte_unmap_unlock(ptep, ptl);
+	*prot = pgprot_val(args.pgprot);
+	*phys = (resource_size_t)args.pfn << PAGE_SHIFT;
+	follow_pfnmap_end(&args);
 	return 0;
 }