mm/migration: return errno when isolate_huge_page failed

[ Upstream commit 7ce82f4c3f3ead13a9d9498768e3b1a79975c4d8 ]

We might fail to isolate huge page due to e.g.  the page is under
migration which cleared HPageMigratable.  We should return errno in this
case rather than always return 1 which could confuse the user, i.e.  the
caller might think all of the memory is migrated while the hugetlb page is
left behind.  We make the prototype of isolate_huge_page consistent with
isolate_lru_page as suggested by Huang Ying and rename isolate_huge_page
to isolate_hugetlb as suggested by Muchun to improve the readability.

Link: https://lkml.kernel.org/r/20220530113016.16663-4-linmiaohe@huawei.com
Fixes: e8db67eb0d ("mm: migrate: move_pages() supports thp migration")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Huang Ying <ying.huang@intel.com>
Reported-by: kernel test robot <lkp@intel.com> (build error)
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: 73bdf65ea748 ("migrate: hugetlb: check for hugetlb shared PMD in node migration")
Signed-off-by: Sasha Levin <sashal@kernel.org>

mm/memory_hotplug.c

@@ -1288,7 +1288,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 
 		if (PageHuge(page)) {
 			pfn = page_to_pfn(head) + compound_nr(head) - 1;
-			isolate_huge_page(head, &source);
+			isolate_hugetlb(head, &source);
 			continue;
 		} else if (PageTransHuge(page))
 			pfn = page_to_pfn(head) + thp_nr_pages(page) - 1;