--- ../../linux-2.4.2/linux/fs/buffer.c	Fri Feb  9 11:29:44 2001
+++ fs/buffer.c	Thu Mar  1 11:02:01 2001
@@ -161,6 +161,40 @@
 	atomic_dec(&bh->b_count);
 }
 
+
+#define buffer_delay_busy(bh) \
+	(test_bit(BH_Delay, &bh->b_state) && bh->b_page && PageLocked(bh->b_page))
+	
+static void
+_write_buffer(struct buffer_head *bh)
+{
+	struct page *page = bh->b_page;
+
+	if (!page || TryLockPage(page)) {
+		if (current->need_resched)
+			schedule();
+		return;
+	}
+	/*
+	 * Raced with someone?
+	 */
+	if (page->buffers != bh || !buffer_delay(bh) || !buffer_dirty(bh)) {
+		UnlockPage(page);
+		return;
+	}
+	page->mapping->a_ops->writepage(page);
+}
+
+static inline void
+write_buffer(struct buffer_head *bh)
+{
+	if (!buffer_delay(bh))
+		ll_rw_block(WRITE, 1, &bh);
+	else
+		_write_buffer(bh);
+}
+
+
 /* Call sync_buffers with wait!=0 to ensure that the call does not
  * return until all buffer writes have completed.  Sync() may return
  * before the writes have finished; fsync() may not.
@@ -232,7 +266,7 @@
 
 			atomic_inc(&bh->b_count);
 			spin_unlock(&lru_list_lock);
-			ll_rw_block(WRITE, 1, &bh);
+			write_buffer(bh);
 			atomic_dec(&bh->b_count);
 			retry = 1;
 			goto repeat;
@@ -507,6 +541,8 @@
 	struct bh_free_head *head = &free_list[BUFSIZE_INDEX(bh->b_size)];
 	struct buffer_head **bhp = &head->list;
 
+	if (test_bit(BH_Delay, &bh->b_state))
+		BUG();
 	bh->b_state = 0;
 
 	spin_lock(&head->lock);
@@ -879,7 +915,7 @@
 			if (buffer_dirty(bh)) {
 				atomic_inc(&bh->b_count);
 				spin_unlock(&lru_list_lock);
-				ll_rw_block(WRITE, 1, &bh);
+				write_buffer(bh);
 				brelse(bh);
 				spin_lock(&lru_list_lock);
 			}
@@ -1394,6 +1430,11 @@
 
 	head = page->buffers;
 	bh = head;
+
+	if (buffer_delay(bh)) {
+		page->mapping->a_ops->writepage_nounlock(page);
+		return 0; /* just started I/O ... likely didn't complete */
+	}
 	do {
 		unsigned int next_off = curr_off + bh->b_size;
 		next = bh->b_this_page;
@@ -2334,7 +2375,7 @@
 			if (wait > 1)
 				__wait_on_buffer(p);
 		} else if (buffer_dirty(p))
-			ll_rw_block(WRITE, 1, &p);
+			write_buffer(p);
 	} while (tmp != bh);
 }
 
@@ -2361,6 +2402,11 @@
 	int index = BUFSIZE_INDEX(bh->b_size);
 	int loop = 0;
 
+	if (buffer_delay(bh)) {
+		if (wait)
+			page->mapping->a_ops->writepage_nounlock(page);
+		return 0; /* just started I/O ... likely didn't complete */
+	}
 cleaned_buffers_try_again:
 	spin_lock(&lru_list_lock);
 	write_lock(&hash_table_lock);
@@ -2562,7 +2608,7 @@
 			__refile_buffer(bh);
 			continue;
 		}
-		if (buffer_locked(bh))
+		if (buffer_locked(bh) || buffer_delay_busy(bh))
 			continue;
 
 		if (check_flushtime) {
@@ -2580,7 +2626,7 @@
 		/* OK, now we are committed to write it out. */
 		atomic_inc(&bh->b_count);
 		spin_unlock(&lru_list_lock);
-		ll_rw_block(WRITE, 1, &bh);
+		write_buffer(bh);
 		atomic_dec(&bh->b_count);
 
 		if (current->need_resched)