[Sheepdog] [PATCH v2] sheep: fix get_nr_copies()

[Liu Yuan]

From: Liu Yuan <tailai.ly at taobao.com>

We should never return anything greater than sys->nr_copies.

- use min() to get the better readability
- change this function into 'static inline'
- change sys->nr_copies as 'int' to stay in line with nr_zones

Signed-off-by: Liu Yuan <tailai.ly at taobao.com>
---
 V2:
 - use min() as Christoph suggests
 - make it inline

 sheep/group.c      |   19 -------------------
 sheep/sheep_priv.h |   19 ++++++++++++++++---
 2 files changed, 16 insertions(+), 22 deletions(-)

diff --git a/sheep/group.c b/sheep/group.c
index ea02602..24e6b15 100644
--- a/sheep/group.c
+++ b/sheep/group.c
@@ -32,13 +32,6 @@ struct node {
 	struct list_head list;
 };
 
-struct vnode_info {
-	struct sd_vnode entries[SD_MAX_VNODES];
-	int nr_vnodes;
-	int nr_zones;
-	int refcnt;
-};
-
 struct join_message {
 	uint8_t proto_ver;
 	uint8_t nr_copies;
@@ -197,18 +190,6 @@ static int update_vnode_info(void)
 	return 0;
 }
 
-/*
- * If we have less zones available than the desired redundancy we have to do
- * with nr_zones copies, sorry.
- */
-int get_nr_copies(struct vnode_info *vnode_info)
-{
-	int nr_copies = vnode_info->nr_zones;
-	if (nr_copies < sys->nr_copies)
-		nr_copies = sys->nr_copies;
-	return nr_copies;
-}
-
 static void do_cluster_op(void *arg)
 {
 	struct vdi_op_message *msg = arg;
diff --git a/sheep/sheep_priv.h b/sheep/sheep_priv.h
index afd5c1b..bdaed8d 100644
--- a/sheep/sheep_priv.h
+++ b/sheep/sheep_priv.h
@@ -63,7 +63,12 @@ struct client_info {
 };
 
 struct request;
-struct vnode_info;
+struct vnode_info {
+	struct sd_vnode entries[SD_MAX_VNODES];
+	int nr_vnodes;
+	int nr_zones;
+	int refcnt;
+};
 
 typedef void (*req_end_t) (struct request *);
 
@@ -136,7 +141,7 @@ struct cluster_info {
 	struct list_head consistent_obj_list;
 	struct list_head blocking_conn_list;
 
-	uint32_t nr_copies;
+	int nr_copies;
 
 	struct list_head request_queue;
 	struct list_head event_queue;
@@ -212,6 +217,15 @@ extern char *obj_path;
 extern mode_t def_fmode;
 extern mode_t def_dmode;
 
+/*
+ * If we have less zones available than the desired redundancy we have to do
+ * with nr_zones copies, sorry.
+ */
+static inline int get_nr_copies(struct vnode_info *vnode_info)
+{
+	return min(vnode_info->nr_zones, sys->nr_copies);
+}
+
 int create_listen_port(int port, void *data);
 
 int init_store(const char *dir);
@@ -239,7 +253,6 @@ void put_vnode_info(struct vnode_info *vnodes);
 
 struct sd_vnode *oid_to_vnode(struct vnode_info *vnode_info, uint64_t oid,
 		int copy_idx);
-int get_nr_copies(struct vnode_info *vnode_info);
 
 int is_access_to_busy_objects(uint64_t oid);
 
-- 
1.7.8.2