Split the origin_resume() code which calculates the minimum chunk size
of all related snapshots into a separate function,
min_chunk_size(). This function will be used by the resume() function
for the merged target.

Index: linux-2.6.16.i686/drivers/md/dm-snap.c
===================================================================
--- linux-2.6.16.i686.orig/drivers/md/dm-snap.c	2006-05-04 12:50:43.000000000 +0100
+++ linux-2.6.16.i686/drivers/md/dm-snap.c	2006-05-05 14:20:58.000000000 +0100
@@ -1218,15 +1218,10 @@ static int origin_map(struct dm_target *
 
 #define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r))
 
-/*
- * Set the target "split_io" field to the minimum of all the snapshots'
- * chunk sizes.
- */
-static void origin_resume(struct dm_target *ti)
+static inline chunk_t min_chunk_size(struct dm_dev *dev)
 {
-	struct dm_dev *dev = (struct dm_dev *) ti->private;
-	struct dm_snapshot *snap;
 	struct origin *o;
+	struct dm_snapshot *snap;
 	chunk_t chunk_size = 0;
 
 	down_read(&_origins_lock);
@@ -1236,7 +1231,18 @@ static void origin_resume(struct dm_targ
 			chunk_size = min_not_zero(chunk_size, snap->chunk_size);
 	up_read(&_origins_lock);
 
-	ti->split_io = chunk_size;
+	return chunk_size;
+}
+
+/*
+ * Set the target "split_io" field to the minimum of all the snapshots'
+ * chunk sizes.
+ */
+static void origin_resume(struct dm_target *ti)
+{
+	struct dm_dev *dev = (struct dm_dev *) ti->private;
+
+	ti->split_io = min_chunk_size(dev);
 }
 
 static int origin_status(struct dm_target *ti, status_type_t type, char *result,