From c4b364ce1270d689ee5010001344b8eae3685f32 Mon Sep 17 00:00:00 2001 From: Yangbo Lu Date: Tue, 27 Apr 2021 12:22:00 +0800 Subject: [PATCH] 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 --- drivers/net/dsa/ocelot/felix.c | 2 +- drivers/net/dsa/sja1105/sja1105_main.c | 2 +- drivers/net/dsa/sja1105/sja1105_ptp.c | 4 ++-- drivers/net/ethernet/mscc/ocelot.c | 6 +++--- drivers/net/ethernet/mscc/ocelot_net.c | 2 +- include/linux/dsa/sja1105.h | 3 ++- include/net/dsa.h | 14 -------------- include/soc/mscc/ocelot.h | 8 ++++++++ net/dsa/slave.c | 2 +- net/dsa/tag_ocelot.c | 8 ++++---- net/dsa/tag_ocelot_8021q.c | 8 ++++---- 11 files changed, 27 insertions(+), 32 deletions(-) diff --git a/drivers/net/dsa/ocelot/felix.c b/drivers/net/dsa/ocelot/felix.c index fe7e8ba..b28280b 100644 --- a/drivers/net/dsa/ocelot/felix.c +++ b/drivers/net/dsa/ocelot/felix.c @@ -1408,7 +1408,7 @@ static void felix_txtstamp(struct dsa_switch *ds, int port, return; ocelot_port_add_txtstamp_skb(ocelot, port, clone); - DSA_SKB_CB(skb)->clone = clone; + OCELOT_SKB_CB(skb)->clone = clone; } } diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c index d9c198c..405024b 100644 --- a/drivers/net/dsa/sja1105/sja1105_main.c +++ b/drivers/net/dsa/sja1105/sja1105_main.c @@ -3137,7 +3137,7 @@ static void sja1105_port_deferred_xmit(struct kthread_work *work) struct sk_buff *skb; while ((skb = skb_dequeue(&sp->xmit_queue)) != NULL) { - struct sk_buff *clone = DSA_SKB_CB(skb)->clone; + struct sk_buff *clone = SJA1105_SKB_CB(skb)->clone; mutex_lock(&priv->mgmt_lock); diff --git a/drivers/net/dsa/sja1105/sja1105_ptp.c b/drivers/net/dsa/sja1105/sja1105_ptp.c index a514008..0bc566b 100644 --- a/drivers/net/dsa/sja1105/sja1105_ptp.c +++ b/drivers/net/dsa/sja1105/sja1105_ptp.c @@ -432,7 +432,7 @@ bool sja1105_port_rxtstamp(struct dsa_switch *ds, int port, } /* Called from dsa_skb_tx_timestamp. This callback is just to clone - * the skb and have it available in DSA_SKB_CB in the .port_deferred_xmit + * the skb and have it available in SJA1105_SKB_CB in the .port_deferred_xmit * callback, where we will timestamp it synchronously. */ void sja1105_port_txtstamp(struct dsa_switch *ds, int port, struct sk_buff *skb) @@ -448,7 +448,7 @@ void sja1105_port_txtstamp(struct dsa_switch *ds, int port, struct sk_buff *skb) if (!clone) return; - DSA_SKB_CB(skb)->clone = clone; + SJA1105_SKB_CB(skb)->clone = clone; } static int sja1105_ptp_reset(struct dsa_switch *ds) diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c index 8d06ffa..7da2dd1 100644 --- a/drivers/net/ethernet/mscc/ocelot.c +++ b/drivers/net/ethernet/mscc/ocelot.c @@ -538,8 +538,8 @@ void ocelot_port_add_txtstamp_skb(struct ocelot *ocelot, int port, spin_lock(&ocelot_port->ts_id_lock); skb_shinfo(clone)->tx_flags |= SKBTX_IN_PROGRESS; - /* Store timestamp ID in cb[0] of sk_buff */ - clone->cb[0] = ocelot_port->ts_id; + /* Store timestamp ID in OCELOT_SKB_CB(clone)->ts_id */ + OCELOT_SKB_CB(clone)->ts_id = ocelot_port->ts_id; ocelot_port->ts_id = (ocelot_port->ts_id + 1) % 4; skb_queue_tail(&ocelot_port->tx_skbs, clone); @@ -604,7 +604,7 @@ void ocelot_get_txtstamp(struct ocelot *ocelot) spin_lock_irqsave(&port->tx_skbs.lock, flags); skb_queue_walk_safe(&port->tx_skbs, skb, skb_tmp) { - if (skb->cb[0] != id) + if (OCELOT_SKB_CB(skb)->ts_id != id) continue; __skb_unlink(skb, &port->tx_skbs); skb_match = skb; diff --git a/drivers/net/ethernet/mscc/ocelot_net.c b/drivers/net/ethernet/mscc/ocelot_net.c index 36f32a4..789a5fba 100644 --- a/drivers/net/ethernet/mscc/ocelot_net.c +++ b/drivers/net/ethernet/mscc/ocelot_net.c @@ -520,7 +520,7 @@ static netdev_tx_t ocelot_port_xmit(struct sk_buff *skb, struct net_device *dev) ocelot_port_add_txtstamp_skb(ocelot, port, clone); - rew_op |= clone->cb[0] << 3; + rew_op |= OCELOT_SKB_CB(clone)->ts_id << 3; } } diff --git a/include/linux/dsa/sja1105.h b/include/linux/dsa/sja1105.h index dd93735..1eb8456 100644 --- a/include/linux/dsa/sja1105.h +++ b/include/linux/dsa/sja1105.h @@ -47,11 +47,12 @@ struct sja1105_tagger_data { }; struct sja1105_skb_cb { + struct sk_buff *clone; u32 meta_tstamp; }; #define SJA1105_SKB_CB(skb) \ - ((struct sja1105_skb_cb *)DSA_SKB_CB_PRIV(skb)) + ((struct sja1105_skb_cb *)((skb)->cb)) struct sja1105_port { u16 subvlan_map[DSA_8021Q_N_SUBVLAN]; diff --git a/include/net/dsa.h b/include/net/dsa.h index 73ce6ce..e1a2610 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -117,20 +117,6 @@ struct dsa_netdevice_ops { #define MODULE_ALIAS_DSA_TAG_DRIVER(__proto) \ MODULE_ALIAS(DSA_TAG_DRIVER_ALIAS __stringify(__proto##_VALUE)) -struct dsa_skb_cb { - struct sk_buff *clone; -}; - -struct __dsa_skb_cb { - struct dsa_skb_cb cb; - u8 priv[48 - sizeof(struct dsa_skb_cb)]; -}; - -#define DSA_SKB_CB(skb) ((struct dsa_skb_cb *)((skb)->cb)) - -#define DSA_SKB_CB_PRIV(skb) \ - ((void *)(skb)->cb + offsetof(struct __dsa_skb_cb, priv)) - struct dsa_switch_tree { struct list_head list; diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h index 68cdc7c..f075aaf 100644 --- a/include/soc/mscc/ocelot.h +++ b/include/soc/mscc/ocelot.h @@ -689,6 +689,14 @@ struct ocelot_policer { u32 burst; /* bytes */ }; +struct ocelot_skb_cb { + struct sk_buff *clone; + u8 ts_id; +}; + +#define OCELOT_SKB_CB(skb) \ + ((struct ocelot_skb_cb *)((skb)->cb)) + #define ocelot_read_ix(ocelot, reg, gi, ri) __ocelot_read_ix(ocelot, reg, reg##_GSZ * (gi) + reg##_RSZ * (ri)) #define ocelot_read_gix(ocelot, reg, gi) __ocelot_read_ix(ocelot, reg, reg##_GSZ * (gi)) #define ocelot_read_rix(ocelot, reg, ri) __ocelot_read_ix(ocelot, reg, reg##_RSZ * (ri)) diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 85e51f4..8c0f3c6 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 f9df9ca..1100a16 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 5f3e8e1..a001a7e 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) -- 2.7.4