writeback: Remove writeback_use_writepage()

The ->writepage operation has been removed from all filesystems but
shmem and swap, neither of which call in here.  Remove this alternative
to calling ->writepages.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250402150005.2309458-5-willy@infradead.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index c81624bc39697153f12e96d9a32dc8ca3fab74ef..76200cd85fe7c5042a87c4bd422daa92704c1c65 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2621,27 +2621,6 @@ int write_cache_pages(struct address_space *mapping,
 }
 EXPORT_SYMBOL(write_cache_pages);
 
-static int writeback_use_writepage(struct address_space *mapping,
-               struct writeback_control *wbc)
-{
-       struct folio *folio = NULL;
-       struct blk_plug plug;
-       int err;
-
-       blk_start_plug(&plug);
-       while ((folio = writeback_iter(mapping, wbc, folio, &err))) {
-               err = mapping->a_ops->writepage(&folio->page, wbc);
-               if (err == AOP_WRITEPAGE_ACTIVATE) {
-                       folio_unlock(folio);
-                       err = 0;
-               }
-               mapping_set_error(mapping, err);
-       }
-       blk_finish_plug(&plug);
-
-       return err;
-}
-
 int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
 {
        int ret;
@@ -2652,14 +2631,11 @@ int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
        wb = inode_to_wb_wbc(mapping->host, wbc);
        wb_bandwidth_estimate_start(wb);
        while (1) {
-               if (mapping->a_ops->writepages) {
+               if (mapping->a_ops->writepages)
                        ret = mapping->a_ops->writepages(mapping, wbc);
-               } else if (mapping->a_ops->writepage) {
-                       ret = writeback_use_writepage(mapping, wbc);
-               } else {
+               else
                        /* deal with chardevs and other special files */
                        ret = 0;
-               }
                if (ret != -ENOMEM || wbc->sync_mode != WB_SYNC_ALL)
                        break;