[PATCH 02/15 net-next,v2] net: sched: add tcf_block_cb_alloc()

[Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>]

Add a new helper function to allocate tcf_block_cb objects.

Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
v2: return -EOPNOTSUPP if sched/cls_api is disabled, per Marcelo Ricardo Leitner .

 include/net/pkt_cls.h |  8 ++++++++
 net/sched/cls_api.c   | 27 +++++++++++++++++++++------
 2 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index 1a7596ba0dbe..a756d895c7a4 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -72,6 +72,8 @@ static inline struct Qdisc *tcf_block_q(struct tcf_block *block)
 	return block->q;
 }
 
+struct tcf_block_cb *tcf_block_cb_alloc(tc_setup_cb_t *cb,
+					void *cb_ident, void *cb_priv);
 void *tcf_block_cb_priv(struct tcf_block_cb *block_cb);
 struct tcf_block_cb *tcf_block_cb_lookup(struct tcf_block *block,
 					 tc_setup_cb_t *cb, void *cb_ident);
@@ -150,6 +152,12 @@ void tc_setup_cb_block_unregister(struct tcf_block *block, tc_setup_cb_t *cb,
 {
 }
 
+static inline struct tcf_block_cb *
+tcf_block_cb_alloc(tc_setup_cb_t *cb, void *cb_ident, void *cb_priv)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
 static inline
 void *tcf_block_cb_priv(struct tcf_block_cb *block_cb)
 {
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index b2417fda26ec..6cd76e3df2be 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -746,6 +746,23 @@ unsigned int tcf_block_cb_decref(struct tcf_block_cb *block_cb)
 }
 EXPORT_SYMBOL(tcf_block_cb_decref);
 
+struct tcf_block_cb *tcf_block_cb_alloc(tc_setup_cb_t *cb,
+					void *cb_ident, void *cb_priv)
+{
+	struct tcf_block_cb *block_cb;
+
+	block_cb = kzalloc(sizeof(*block_cb), GFP_KERNEL);
+	if (!block_cb)
+		return ERR_PTR(-ENOMEM);
+
+	block_cb->cb = cb;
+	block_cb->cb_ident = cb_ident;
+	block_cb->cb_priv = cb_priv;
+
+	return block_cb;
+}
+EXPORT_SYMBOL(tcf_block_cb_alloc);
+
 struct tcf_block_cb *__tcf_block_cb_register(struct tcf_block *block,
 					     tc_setup_cb_t *cb, void *cb_ident,
 					     void *cb_priv,
@@ -761,12 +778,10 @@ struct tcf_block_cb *__tcf_block_cb_register(struct tcf_block *block,
 	if (err)
 		return ERR_PTR(err);
 
-	block_cb = kzalloc(sizeof(*block_cb), GFP_KERNEL);
-	if (!block_cb)
-		return ERR_PTR(-ENOMEM);
-	block_cb->cb = cb;
-	block_cb->cb_ident = cb_ident;
-	block_cb->cb_priv = cb_priv;
+	block_cb = tcf_block_cb_alloc(cb, cb_ident, cb_priv);
+	if (IS_ERR(block_cb))
+		return block_cb;
+
 	list_add(&block_cb->list, &block->cb_list);
 	return block_cb;
 }
-- 
2.11.0