gfs2: use a folio inside gfs2_jdata_writepage()

Patch series "gfs2/buffer folio changes for 6.5", v3.

This kind of started off as a gfs2 patch series, then became entwined with
buffer heads once I realised that gfs2 was the only remaining caller of
__block_write_full_page().  For those not in the gfs2 world, the big point
of this series is that block_write_full_page() should now handle large
folios correctly.


This patch (of 14):

Replace a few implicit calls to compound_head() with one explicit one.

Link: https://lkml.kernel.org/r/20230612210141.730128-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20230612210141.730128-2-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/gfs2/aops.c

@@ -150,20 +150,21 @@ static int __gfs2_jdata_writepage(struct page *page, struct writeback_control *w
 
 static int gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
 {
+	struct folio *folio = page_folio(page);
 	struct inode *inode = page->mapping->host;
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_sbd *sdp = GFS2_SB(inode);
 
 	if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl)))
 		goto out;
-	if (PageChecked(page) || current->journal_info)
+	if (folio_test_checked(folio) || current->journal_info)
 		goto out_ignore;
-	return __gfs2_jdata_writepage(page, wbc);
+	return __gfs2_jdata_writepage(&folio->page, wbc);
 
 out_ignore:
-	redirty_page_for_writepage(wbc, page);
+	folio_redirty_for_writepage(wbc, folio);
 out:
-	unlock_page(page);
+	folio_unlock(folio);
 	return 0;
 }