gfs2: remove ->writepage

->writepage is only used for single page writeback from memory reclaim,
and not called at all for cgroup writeback.  Follow the lead of XFS
and remove ->writepage and rely entirely on ->writepages.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

fs/gfs2/aops.c

@@ -81,31 +81,6 @@ static int gfs2_get_block_noalloc(struct inode *inode, sector_t lblock,
 	return 0;
 }
 
-/**
- * gfs2_writepage - Write page for writeback mappings
- * @page: The page
- * @wbc: The writeback control
- */
-static int gfs2_writepage(struct page *page, struct writeback_control *wbc)
-{
-	struct inode *inode = page->mapping->host;
-	struct gfs2_inode *ip = GFS2_I(inode);
-	struct gfs2_sbd *sdp = GFS2_SB(inode);
-	struct iomap_writepage_ctx wpc = { };
-
-	if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl)))
-		goto out;
-	if (current->journal_info)
-		goto redirty;
-	return iomap_writepage(page, wbc, &wpc, &gfs2_writeback_ops);
-
-redirty:
-	redirty_page_for_writepage(wbc, page);
-out:
-	unlock_page(page);
-	return 0;
-}
-
 /**
  * gfs2_write_jdata_page - gfs2 jdata-specific version of block_write_full_page
  * @page: The page to write
@@ -765,7 +740,6 @@ bool gfs2_release_folio(struct folio *folio, gfp_t gfp_mask)
 }
 
 static const struct address_space_operations gfs2_aops = {
-	.writepage = gfs2_writepage,
 	.writepages = gfs2_writepages,
 	.read_folio = gfs2_read_folio,
 	.readahead = gfs2_readahead,