4 files changed, 74 insertions, 0 deletions

diff --git a/libglusterfs/src/glusterfs.h b/libglusterfs/src/glusterfs.h
index 1d0369c4d..669bbfaeb 100644
--- a/libglusterfs/src/glusterfs.h
+++ b/libglusterfs/src/glusterfs.h
@@ -310,4 +310,6 @@ int glusterfs_graph_destroy (glusterfs_graph_t *graph);
 int glusterfs_graph_activate (glusterfs_graph_t *graph, glusterfs_ctx_t *ctx);
 glusterfs_graph_t *glusterfs_graph_construct (FILE *fp);
 glusterfs_graph_t *glusterfs_graph_new ();
+int glusterfs_graph_reconfigure (glusterfs_graph_t *oldgraph,
+                                  glusterfs_graph_t *newgraph);
 #endif /* _GLUSTERFS_H */
diff --git a/libglusterfs/src/graph.c b/libglusterfs/src/graph.c
index 4adb04a39..c44fa44ad 100644
--- a/libglusterfs/src/graph.c
+++ b/libglusterfs/src/graph.c
@@ -495,6 +495,24 @@ glusterfs_graph_activate (glusterfs_graph_t *graph, glusterfs_ctx_t *ctx)
         return 0;
 }
 
+int
+glusterfs_graph_reconfigure (glusterfs_graph_t *oldgraph,
+                             glusterfs_graph_t *newgraph)
+{
+        xlator_t *old_xl = NULL;
+        xlator_t *new_xl = NULL;
+        int ret = 0;
+
+        GF_ASSERT (oldgraph);
+        GF_ASSERT (newgraph);
+
+        old_xl   = oldgraph->first;
+        new_xl   = newgraph->first;
+
+        ret = xlator_tree_reconfigure (old_xl, new_xl);
+
+        return ret;
+}
 
 int
 glusterfs_graph_destroy (glusterfs_graph_t *graph)
diff --git a/libglusterfs/src/xlator.c b/libglusterfs/src/xlator.c
index 2074c143c..393088019 100644
--- a/libglusterfs/src/xlator.c
+++ b/libglusterfs/src/xlator.c
@@ -749,6 +749,12 @@ xlator_set_type (xlator_t *xl,
                         dlerror ());
         }
 
+	if (!(xl->reconfigure = dlsym (handle, "reconfigure"))) {
+		gf_log ("xlator", GF_LOG_ERROR,
+			"dlsym(reconfigure) on %s -- neglecting",
+			dlerror());
+	}
+
 	INIT_LIST_HEAD (&xl->volume_options);
 
 	vol_opt = GF_CALLOC (1, sizeof (volume_opt_list_t),
@@ -910,6 +916,35 @@ xlator_fini_rec (xlator_t *xl)
 	}
 }
 
+static void
+xlator_reconfigure_rec (xlator_t *old_xl, xlator_t *new_xl)
+{
+	xlator_list_t *trav1 = NULL;
+        xlator_list_t *trav2 = NULL;
+
+	if (old_xl == NULL || new_xl == NULL)	{
+		gf_log ("xlator", GF_LOG_DEBUG, "invalid argument");
+		return;
+	}
+
+	trav1 = old_xl->children;
+        trav2 = new_xl->children;
+
+	while (trav1 && trav2) {
+		xlator_reconfigure_rec (trav1->xlator, trav2->xlator);
+
+		gf_log (trav1->xlator->name, GF_LOG_DEBUG, "reconfigured");
+
+		trav1 = trav1->next;
+                trav2 = trav2->next;
+	}
+
+        if (old_xl->reconfigure)
+                old_xl->reconfigure (old_xl, new_xl->options);
+        else
+                gf_log (old_xl->name, GF_LOG_DEBUG, "No reconfigure() found");
+
+}
 
 int
 xlator_notify (xlator_t *xl, int event, void *data, ...)
@@ -976,6 +1011,23 @@ xlator_tree_fini (xlator_t *xl)
 	xlator_fini_rec (top);
 }
 
+int
+xlator_tree_reconfigure (xlator_t *old_xl, xlator_t *new_xl)
+{
+        xlator_t *new_top = NULL;
+        xlator_t *old_top = NULL;
+
+        GF_ASSERT (old_xl);
+        GF_ASSERT (new_xl);
+
+        old_top = old_xl;
+        new_top = new_xl;
+
+	xlator_reconfigure_rec (old_top, new_top);
+
+        return 0;
+}
+
 
 int
 xlator_tree_free (xlator_t *tree)
diff --git a/libglusterfs/src/xlator.h b/libglusterfs/src/xlator.h
index 2aa9b372b..84ad990d4 100644
--- a/libglusterfs/src/xlator.h
+++ b/libglusterfs/src/xlator.h
@@ -806,6 +806,7 @@ struct _xlator {
 
 	void              (*fini) (xlator_t *this);
 	int32_t           (*init) (xlator_t *this);
+        int32_t           (*reconfigure) (xlator_t *this, dict_t *options);
 	int32_t           (*mem_acct_init) (xlator_t *this);
 	event_notify_fn_t notify;
 
@@ -854,6 +855,7 @@ int loc_copy (loc_t *dst, loc_t *src);
 #define loc_dup(src, dst) loc_copy(dst, src)
 void loc_wipe (loc_t *loc);
 int xlator_mem_acct_init (xlator_t *xl, int num_types);
+int xlator_tree_reconfigure (xlator_t *old_xl, xlator_t *new_xl);
 
 #define GF_STAT_PRINT_FMT_STR "%"PRIx64",%"PRIx64",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx64",%"PRIx64",%"PRIx32",%"PRIx64",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32"\n"