Revert "writeback: introduce writeback_control.more_io to indicate more io"

This reverts commit 2e6883bdf4, as
requested by Fengguang Wu.  It's not quite fully baked yet, and while
there are patches around to fix the problems it caused, they should get
more testing.  Says Fengguang: "I'll resend them both for -mm later on,
in a more complete patchset".

See

	http://bugzilla.kernel.org/show_bug.cgi?id=9738

for some of this discussion.

Requested-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/fs-writeback.c

@@ -482,8 +482,6 @@ sync_sb_inodes(struct super_block *sb, struct writeback_control *wbc)
 		if (wbc->nr_to_write <= 0)
 			break;
 	}
-	if (!list_empty(&sb->s_more_io))
-		wbc->more_io = 1;
 	return;		/* Leave any unwritten inodes on s_io */
 }