[PATCH net-next v5 10/15] net: macsec: PN wrap callback

[Antoine Tenart <antoine.tenart@bootlin.com>]

Allow to call macsec_pn_wrapped from hardware drivers to notify when a
PN rolls over. Some drivers might used an interrupt to implement this.

Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
---
 drivers/net/macsec.c | 24 ++++++++++++++++++------
 include/net/macsec.h |  2 ++
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index ace7fc98e8dd..fc481616632c 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -423,6 +423,22 @@ static struct macsec_eth_header *macsec_ethhdr(struct sk_buff *skb)
 	return (struct macsec_eth_header *)skb_mac_header(skb);
 }
 
+static void __macsec_pn_wrapped(struct macsec_secy *secy,
+				struct macsec_tx_sa *tx_sa)
+{
+	pr_debug("PN wrapped, transitioning to !oper\n");
+	tx_sa->active = false;
+	if (secy->protect_frames)
+		secy->operational = false;
+}
+
+void macsec_pn_wrapped(struct macsec_secy *secy, struct macsec_tx_sa *tx_sa)
+{
+	spin_lock_bh(&tx_sa->lock);
+	__macsec_pn_wrapped(secy, tx_sa);
+	spin_unlock_bh(&tx_sa->lock);
+}
+
 static u32 tx_sa_update_pn(struct macsec_tx_sa *tx_sa, struct macsec_secy *secy)
 {
 	u32 pn;
@@ -431,12 +447,8 @@ static u32 tx_sa_update_pn(struct macsec_tx_sa *tx_sa, struct macsec_secy *secy)
 	pn = tx_sa->next_pn;
 
 	tx_sa->next_pn++;
-	if (tx_sa->next_pn == 0) {
-		pr_debug("PN wrapped, transitioning to !oper\n");
-		tx_sa->active = false;
-		if (secy->protect_frames)
-			secy->operational = false;
-	}
+	if (tx_sa->next_pn == 0)
+		__macsec_pn_wrapped(secy, tx_sa);
 	spin_unlock_bh(&tx_sa->lock);
 
 	return pn;
diff --git a/include/net/macsec.h b/include/net/macsec.h
index 4d0afb79259e..a08f19099c7a 100644
--- a/include/net/macsec.h
+++ b/include/net/macsec.h
@@ -220,4 +220,6 @@ struct macsec_ops {
 	int (*mdo_del_txsa)(struct macsec_context *ctx);
 };
 
+void macsec_pn_wrapped(struct macsec_secy *secy, struct macsec_tx_sa *tx_sa);
+
 #endif /* _NET_MACSEC_H_ */
-- 
2.24.1