mm/gup: Convert check_and_migrate_movable_pages() to use a folio

Switch from head pages to folios.  This removes an assumption that
THPs are the only way to have a high-order page.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>

diff --git a/mm/gup.c b/mm/gup.c
index 5edd05d..35d550d 100644 (file)
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1784,43 +1784,44 @@ static long check_and_migrate_movable_pages(unsigned long nr_pages,
                                            unsigned int gup_flags)
 {
        unsigned long isolation_error_count = 0, i;
-       struct page *prev_head = NULL;
+       struct folio *prev_folio = NULL;
        LIST_HEAD(movable_page_list);
        bool drain_allow = true;
        int ret = 0;
 
        for (i = 0; i < nr_pages; i++) {
-               struct page *head = compound_head(pages[i]);
+               struct folio *folio = page_folio(pages[i]);
 
-               if (head == prev_head)
+               if (folio == prev_folio)
                        continue;
-               prev_head = head;
+               prev_folio = folio;
 
-               if (is_pinnable_page(head))
+               if (folio_is_pinnable(folio))
                        continue;
 
                /*
                 * Try to move out any movable page before pinning the range.
                 */
-               if (PageHuge(head)) {
-                       if (!isolate_huge_page(head, &movable_page_list))
+               if (folio_test_hugetlb(folio)) {
+                       if (!isolate_huge_page(&folio->page,
+                                               &movable_page_list))
                                isolation_error_count++;
                        continue;
                }
 
-               if (!PageLRU(head) && drain_allow) {
+               if (!folio_test_lru(folio) && drain_allow) {
                        lru_add_drain_all();
                        drain_allow = false;
                }
 
-               if (isolate_lru_page(head)) {
+               if (folio_isolate_lru(folio)) {
                        isolation_error_count++;
                        continue;
                }
-               list_add_tail(&head->lru, &movable_page_list);
-               mod_node_page_state(page_pgdat(head),
-                                   NR_ISOLATED_ANON + page_is_file_lru(head),
-                                   thp_nr_pages(head));
+               list_add_tail(&folio->lru, &movable_page_list);
+               node_stat_mod_folio(folio,
+                                   NR_ISOLATED_ANON + folio_is_file_lru(folio),
+                                   folio_nr_pages(folio));
        }
 
        if (!list_empty(&movable_page_list) || isolation_error_count)