afs: Fix missing put_page()

BugLink: http://bugs.launchpad.net/bugs/1745052

[ Upstream commit 29c8bbbd ]

In afs_writepages_region(), inside the loop where we find dirty pages to
deal with, one of the if-statements is missing a put_page().
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

fs/afs/write.c

@@ -503,6 +503,7 @@ static int afs_writepages_region(struct address_space *mapping,
 
 		if (PageWriteback(page) || !PageDirty(page)) {
 			unlock_page(page);
+			put_page(page);
 			continue;
 		}