xen/mmu: use copy_page instead of memcpy.

After all, this is what it is there for.
Acked-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

arch/x86/xen/mmu.c

@@ -1754,14 +1754,14 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
 	 * it will be also modified in the __ka space! (But if you just
 	 * modify the PMD table to point to other PTE's or none, then you
 	 * are OK - which is what cleanup_highmap does) */
-	memcpy(level2_ident_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
+	copy_page(level2_ident_pgt, l2);
 	/* Graft it onto L4[511][511] */
-	memcpy(level2_kernel_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
+	copy_page(level2_kernel_pgt, l2);
 
 	/* Get [511][510] and graft that in level2_fixmap_pgt */
 	l3 = m2v(pgd[pgd_index(__START_KERNEL_map + PMD_SIZE)].pgd);
 	l2 = m2v(l3[pud_index(__START_KERNEL_map + PMD_SIZE)].pud);
-	memcpy(level2_fixmap_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
+	copy_page(level2_fixmap_pgt, l2);
 	/* Note that we don't do anything with level1_fixmap_pgt which
 	 * we don't need. */
 
@@ -1821,8 +1821,7 @@ static void __init xen_write_cr3_init(unsigned long cr3)
 	 */
 	swapper_kernel_pmd =
 		extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE);
-	memcpy(swapper_kernel_pmd, initial_kernel_pmd,
-	       sizeof(pmd_t) * PTRS_PER_PMD);
+	copy_page(swapper_kernel_pmd, initial_kernel_pmd);
 	swapper_pg_dir[KERNEL_PGD_BOUNDARY] =
 		__pgd(__pa(swapper_kernel_pmd) | _PAGE_PRESENT);
 	set_page_prot(swapper_kernel_pmd, PAGE_KERNEL_RO);
@@ -1851,11 +1850,11 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
 				  512*1024);
 
 	kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
-	memcpy(initial_kernel_pmd, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);
+	copy_page(initial_kernel_pmd, kernel_pmd);
 
 	xen_map_identity_early(initial_kernel_pmd, max_pfn);
 
-	memcpy(initial_page_table, pgd, sizeof(pgd_t) * PTRS_PER_PGD);
+	copy_page(initial_page_table, pgd);
 	initial_page_table[KERNEL_PGD_BOUNDARY] =
 		__pgd(__pa(initial_kernel_pmd) | _PAGE_PRESENT);