From c4b364ce1270d689ee5010001344b8eae3685f32 Mon Sep 17 00:00:00 2001 From: Yangbo Lu Date: Tue, 27 Apr 2021 12:22:00 +0800 Subject: net: dsa: free skb->cb usage in core driver Free skb->cb usage in core driver and let device drivers decide to use or not. The reason having a DSA_SKB_CB(skb)->clone was because dsa_skb_tx_timestamp() which may set the clone pointer was called before p->xmit() which would use the clone if any, and the device driver has no way to initialize the clone pointer. This patch just put memset(skb->cb, 0, sizeof(skb->cb)) at beginning of dsa_slave_xmit(). Some new features in the future, like one-step timestamp may need more bytes of skb->cb to use in dsa_skb_tx_timestamp(), and p->xmit(). Signed-off-by: Yangbo Lu Acked-by: Richard Cochran Signed-off-by: David S. Miller --- net/dsa/slave.c | 2 +- net/dsa/tag_ocelot.c | 8 ++++---- net/dsa/tag_ocelot_8021q.c | 8 ++++---- 3 files changed, 9 insertions(+), 9 deletions(-) (limited to 'net') diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 85e51f46a9d5..8c0f3c6ab365 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -614,7 +614,7 @@ static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev) dev_sw_netstats_tx_add(dev, 1, skb->len); - DSA_SKB_CB(skb)->clone = NULL; + memset(skb->cb, 0, sizeof(skb->cb)); /* Handle tx timestamp if any */ dsa_skb_tx_timestamp(p, skb); diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c index f9df9cac81c5..1100a16f1032 100644 --- a/net/dsa/tag_ocelot.c +++ b/net/dsa/tag_ocelot.c @@ -15,11 +15,11 @@ static void ocelot_xmit_ptp(struct dsa_port *dp, void *injection, ocelot_port = ocelot->ports[dp->index]; rew_op = ocelot_port->ptp_cmd; - /* Retrieve timestamp ID populated inside skb->cb[0] of the - * clone by ocelot_port_add_txtstamp_skb + /* Retrieve timestamp ID populated inside OCELOT_SKB_CB(clone)->ts_id + * by ocelot_port_add_txtstamp_skb */ if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) - rew_op |= clone->cb[0] << 3; + rew_op |= OCELOT_SKB_CB(clone)->ts_id << 3; ocelot_ifh_set_rew_op(injection, rew_op); } @@ -28,7 +28,7 @@ static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev, __be32 ifh_prefix, void **ifh) { struct dsa_port *dp = dsa_slave_to_port(netdev); - struct sk_buff *clone = DSA_SKB_CB(skb)->clone; + struct sk_buff *clone = OCELOT_SKB_CB(skb)->clone; struct dsa_switch *ds = dp->ds; void *injection; __be32 *prefix; diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c index 5f3e8e124a82..a001a7e3f575 100644 --- a/net/dsa/tag_ocelot_8021q.c +++ b/net/dsa/tag_ocelot_8021q.c @@ -28,11 +28,11 @@ static struct sk_buff *ocelot_xmit_ptp(struct dsa_port *dp, ocelot_port = ocelot->ports[port]; rew_op = ocelot_port->ptp_cmd; - /* Retrieve timestamp ID populated inside skb->cb[0] of the - * clone by ocelot_port_add_txtstamp_skb + /* Retrieve timestamp ID populated inside OCELOT_SKB_CB(clone)->ts_id + * by ocelot_port_add_txtstamp_skb */ if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) - rew_op |= clone->cb[0] << 3; + rew_op |= OCELOT_SKB_CB(clone)->ts_id << 3; ocelot_port_inject_frame(ocelot, port, 0, rew_op, skb); @@ -46,7 +46,7 @@ static struct sk_buff *ocelot_xmit(struct sk_buff *skb, u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index); u16 queue_mapping = skb_get_queue_mapping(skb); u8 pcp = netdev_txq_to_tc(netdev, queue_mapping); - struct sk_buff *clone = DSA_SKB_CB(skb)->clone; + struct sk_buff *clone = OCELOT_SKB_CB(skb)->clone; /* TX timestamping was requested, so inject through MMIO */ if (clone) -- cgit