From: Suparna Bhattacharya

wait_on_page_writeback_range shouldn't wait for pages beyond the
specified range. Ideally, the radix-tree-lookup could accept an
end_index parameter so that it doesn't return the extra pages
in the first place, but for now we just add a few extra checks
to skip such pages.


--- rc3mm3/mm/filemap.c	2004-04-01 15:54:35.141840752 +0530
+++ linux-2.6.5-rc3-mm3/mm/filemap.c	2004-04-01 16:08:50.857752160 +0530
@@ -186,7 +186,8 @@ static int wait_on_page_writeback_range(
 
 	pagevec_init(&pvec, 0);
 	index = start;
-	while ((nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
+	while ((index <= end) && 
+			(nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
 			PAGECACHE_TAG_WRITEBACK,
 			min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
 		unsigned i;
@@ -194,6 +195,10 @@ static int wait_on_page_writeback_range(
 		for (i = 0; i < nr_pages; i++) {
 			struct page *page = pvec.pages[i];
 
+			/* until radix tree lookup accepts end_index */
+			if (page->index > end) {
+				continue;
+			}
 			wait_on_page_writeback(page);
 			if (PageError(page))
 				ret = -EIO;