net: sched: keep track of offloaded filters and check tc offload feature

During block bind, we need to check tc offload feature. If it is
disabled yet still the block contains offloaded filters, forbid the
bind. Also forbid to register callback for a block that already
contains offloaded filters, as the play back is not supported now.
For keeping track of offloaded filters there is a new counter
introduced, alongside with couple of helpers called from cls_* code.
These helpers set and clear TCA_CLS_FLAGS_IN_HW flag.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 18 insertions, 0 deletions

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 54b9a1c..bf5cc0a 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -289,8 +289,26 @@ struct tcf_block {
 	struct list_head cb_list;
 	struct list_head owner_list;
 	bool keep_dst;
+	unsigned int offloadcnt; /* Number of oddloaded filters */
+	unsigned int nooffloaddevcnt; /* Number of devs unable to do offload */
 };
 
+static inline void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
+{
+	if (*flags & TCA_CLS_FLAGS_IN_HW)
+		return;
+	*flags |= TCA_CLS_FLAGS_IN_HW;
+	block->offloadcnt++;
+}
+
+static inline void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
+{
+	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
+		return;
+	*flags &= ~TCA_CLS_FLAGS_IN_HW;
+	block->offloadcnt--;
+}
+
 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
 {
 	struct qdisc_skb_cb *qcb;