x86: remove custom definition of mk_pte()

Move the shadow stack check to pfn_pte() which lets us use the common
definition of mk_pte().

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Matthew Wilcox (Oracle) <[e-mail]>
Acked-by: Dave Hansen <[e-mail]>
Cc: Zi Yan <[e-mail]>
Cc: Alexander Gordeev <[e-mail]>
Cc: Andreas Larsson <[e-mail]>
Cc: Anton Ivanov <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Cc: "David S. Miller" <[e-mail]>
Cc: Geert Uytterhoeven <[e-mail]>
Cc: Johannes Berg <[e-mail]>
Cc: Muchun Song <[e-mail]>
Cc: Richard Weinberger <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

arch/x86/include/asm/pgtable.h

···
 static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
 {
 	phys_addr_t pfn = (phys_addr_t)page_nr << PAGE_SHIFT;
+	/* This bit combination is used to mark shadow stacks */
+	WARN_ON_ONCE((pgprot_val(pgprot) & (_PAGE_DIRTY | _PAGE_RW)) ==
+			_PAGE_DIRTY);
 	pfn ^= protnone_mask(pgprot_val(pgprot));
 	pfn &= PTE_PFN_MASK;
 	return __pte(pfn | check_pgprot(pgprot));
···
  * linux/mmzone.h's __section_mem_map_addr() definition:
  */
 #define pmd_page(pmd)	pfn_to_page(pmd_pfn(pmd))
-
-/*
- * Conversion functions: convert a page and protection to a page entry,
- * and a page entry and page directory to the page they refer to.
- *
- * (Currently stuck as a macro because of indirect forward reference
- * to linux/mm.h:page_to_nid())
- */
-#define mk_pte(page, pgprot)						  \
-({									  \
-	pgprot_t __pgprot = pgprot;					  \
-									  \
-	WARN_ON_ONCE((pgprot_val(__pgprot) & (_PAGE_DIRTY | _PAGE_RW)) == \
-		    _PAGE_DIRTY);					  \
-	pfn_pte(page_to_pfn(page), __pgprot);				  \
-})
 
 static inline int pmd_bad(pmd_t pmd)
 {