mm/filemap: use folio_next_index() for start

Use folio_next_index() instead of open-coding folio->index +
folio_nr_pages(folio) when updating @start in filemap_get_folios_contig(),
filemap_get_folios_tag(), and filemap_get_folios_dirty().

Link: https://lore.kernel.org/20260601110425.44784-1-tanze@kylinos.cn
Signed-off-by: tanze <tanze@kylinos.cn>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/filemap.c b/mm/filemap.c
index 98434acc69c18c69d468a49718fc76b7326d34ba..5d9f9b36e9d8a6a0bb4b3a7ad17d4abf63317c2c 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2284,8 +2284,7 @@ unsigned filemap_get_folios_contig(struct address_space *mapping,
                        goto put_folio;
 
                if (!folio_batch_add(fbatch, folio)) {
-                       nr = folio_nr_pages(folio);
-                       *start = folio->index + nr;
+                       *start = folio_next_index(folio);
                        goto out;
                }
                xas_advance(&xas, folio_next_index(folio) - 1);
@@ -2345,8 +2344,7 @@ unsigned filemap_get_folios_tag(struct address_space *mapping, pgoff_t *start,
                if (xa_is_value(folio))
                        continue;
                if (!folio_batch_add(fbatch, folio)) {
-                       unsigned long nr = folio_nr_pages(folio);
-                       *start = folio->index + nr;
+                       *start = folio_next_index(folio);
                        goto out;
                }
        }
@@ -2404,8 +2402,7 @@ unsigned filemap_get_folios_dirty(struct address_space *mapping, pgoff_t *start,
                        }
                }
                if (!folio_batch_add(fbatch, folio)) {
-                       unsigned long nr = folio_nr_pages(folio);
-                       *start = folio->index + nr;
+                       *start = folio_next_index(folio);
                        goto out;
                }
        }