mm/hugetlb: use helper huge_page_size() to get hugepage size

We can use helper huge_page_size() to get the hugepage size directly to
simplify the code slightly.

[linmiaohe@huawei.com: use helper huge_page_size() to get hugepage size]
  Link: https://lkml.kernel.org/r/20210209021803.49211-1-linmiaohe@huawei.com

Link: https://lkml.kernel.org/r/20210208082450.15716-1-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/hugetlb.c

@@ -3248,7 +3248,7 @@ void __init hugetlb_add_hstate(unsigned int order)
 	BUG_ON(order == 0);
 	h = &hstates[hugetlb_max_hstate++];
 	h->order = order;
-	h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);
+	h->mask = ~(huge_page_size(h) - 1);
 	for (i = 0; i < MAX_NUMNODES; ++i)
 		INIT_LIST_HEAD(&h->hugepage_freelists[i]);
 	INIT_LIST_HEAD(&h->hugepage_activelist);
@@ -3523,7 +3523,7 @@ void hugetlb_report_meminfo(struct seq_file *m)
 	for_each_hstate(h) {
 		unsigned long count = h->nr_huge_pages;
 
-		total += (PAGE_SIZE << huge_page_order(h)) * count;
+		total += huge_page_size(h) * count;
 
 		if (h == &default_hstate)
 			seq_printf(m,
@@ -3536,10 +3536,10 @@ void hugetlb_report_meminfo(struct seq_file *m)
 				   h->free_huge_pages,
 				   h->resv_huge_pages,
 				   h->surplus_huge_pages,
-				   (PAGE_SIZE << huge_page_order(h)) / 1024);
+				   huge_page_size(h) / SZ_1K);
 	}
 
-	seq_printf(m, "Hugetlb:        %8lu kB\n", total / 1024);
+	seq_printf(m, "Hugetlb:        %8lu kB\n", total / SZ_1K);
 }
 
 int hugetlb_report_node_meminfo(char *buf, int len, int nid)
@@ -3573,7 +3573,7 @@ void hugetlb_show_meminfo(void)
 				h->nr_huge_pages_node[nid],
 				h->free_huge_pages_node[nid],
 				h->surplus_huge_pages_node[nid],
-				1UL << (huge_page_order(h) + PAGE_SHIFT - 10));
+				huge_page_size(h) / SZ_1K);
 }
 
 void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm)
@@ -3696,9 +3696,7 @@ static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr)
 
 static unsigned long hugetlb_vm_op_pagesize(struct vm_area_struct *vma)
 {
-	struct hstate *hstate = hstate_vma(vma);
-
-	return 1UL << huge_page_shift(hstate);
+	return huge_page_size(hstate_vma(vma));
 }
 
 /*