[PATCH net-next 04/11] net: dsa: get and put tree reference counting

[Vivien Didelot]

Provide convenient dsa_tree_get and dsa_tree_put functions scoping a DSA
tree used to increment and decrement its reference counter, instead of
poking directly its kref structure.

Signed-off-by: Vivien Didelot <vivien.dide...@savoirfairelinux.com>
---
 net/dsa/dsa2.c | 40 ++++++++++++++++++++++++++++------------
 1 file changed, 28 insertions(+), 12 deletions(-)

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index d3f1a7607463..609d92684505 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -38,15 +38,6 @@ static struct dsa_switch_tree *dsa_get_dst(unsigned int 
index)
        return NULL;
 }
 
-static void dsa_free_dst(struct kref *ref)
-{
-       struct dsa_switch_tree *dst = container_of(ref, struct dsa_switch_tree,
-                                                  refcount);
-
-       list_del(&dst->list);
-       kfree(dst);
-}
-
 static struct dsa_switch_tree *dsa_add_dst(unsigned int index)
 {
        struct dsa_switch_tree *dst;
@@ -65,10 +56,35 @@ static struct dsa_switch_tree *dsa_add_dst(unsigned int 
index)
        return dst;
 }
 
-static void dsa_dst_add_ds(struct dsa_switch_tree *dst,
-                          struct dsa_switch *ds, u32 index)
+static void dsa_tree_free(struct dsa_switch_tree *dst)
+{
+       list_del(&dst->list);
+       kfree(dst);
+}
+
+static void dsa_tree_get(struct dsa_switch_tree *dst)
 {
        kref_get(&dst->refcount);
+}
+
+static void dsa_tree_release(struct kref *ref)
+{
+       struct dsa_switch_tree *dst;
+
+       dst = container_of(ref, struct dsa_switch_tree, refcount);
+
+       dsa_tree_free(dst);
+}
+
+static void dsa_tree_put(struct dsa_switch_tree *dst)
+{
+       kref_put(&dst->refcount, dsa_tree_release);
+}
+
+static void dsa_dst_add_ds(struct dsa_switch_tree *dst,
+                          struct dsa_switch *ds, u32 index)
+{
+       dsa_tree_get(dst);
        dst->ds[index] = ds;
 }
 
@@ -76,7 +92,7 @@ static void dsa_dst_del_ds(struct dsa_switch_tree *dst,
                           struct dsa_switch *ds, u32 index)
 {
        dst->ds[index] = NULL;
-       kref_put(&dst->refcount, dsa_free_dst);
+       dsa_tree_put(dst);
 }
 
 /* For platform data configurations, we need to have a valid name argument to
-- 
2.14.3