[XFS] Dynamically allocate vattr in places it makes sense to do so, to
reduce stack use.  Also re-use vattr in some places so that multiple
copies are not held on-stack.

SGI-PV: 947312
SGI-Modid: xfs-linux-melb:xfs-kern:25369a

Signed-off-by: Nathan Scott <nathans@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_vnode.h b/fs/xfs/linux-2.6/xfs_vnode.h
index 0fe2419..0cf92ca 100644
--- a/fs/xfs/linux-2.6/xfs_vnode.h
+++ b/fs/xfs/linux-2.6/xfs_vnode.h
@@ -490,6 +490,7 @@
 			 (vmap).v_ino	 = (vp)->v_inode.i_ino; }
 
 extern int	vn_revalidate(struct vnode *);
+extern int	__vn_revalidate(struct vnode *, vattr_t *);
 extern void	vn_revalidate_core(struct vnode *, vattr_t *);
 
 extern void	vn_iowait(struct vnode *vp);