GFS2: Use slab for block reservation memory

This patch changes block reservations so it uses slab storage.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/util.h b/fs/gfs2/util.h
index a4ce76c..8fbe6cf 100644
--- a/fs/gfs2/util.h
+++ b/fs/gfs2/util.h
@@ -152,6 +152,7 @@
 extern struct kmem_cache *gfs2_bufdata_cachep;
 extern struct kmem_cache *gfs2_rgrpd_cachep;
 extern struct kmem_cache *gfs2_quotad_cachep;
+extern struct kmem_cache *gfs2_rsrv_cachep;
 extern mempool_t *gfs2_bh_pool;
 
 static inline unsigned int gfs2_tune_get_i(struct gfs2_tune *gt,