[XFS] Export pagevec_lookup for use on the XFS page writeout path,

for dealing with delayed allocate and unwritten extents (as well).
Signed-off-by: NChristoph Hellwig <hch@sgi.com>
Signed-off-by: NNathan Scott <nathans@sgi.com>

mm/swap.c

@@ -384,6 +384,8 @@ unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
 	return pagevec_count(pvec);
 }
 
+EXPORT_SYMBOL(pagevec_lookup);
+
 unsigned pagevec_lookup_tag(struct pagevec *pvec, struct address_space *mapping,
 		pgoff_t *index, int tag, unsigned nr_pages)
 {