[PATCH v2 net-next 08/12] net: dsa: tag_ocelot: single out PTP-related transmit tag processing
From: Vladimir Oltean <olteanv@gmail.com>
Date: 2021-02-13 22:40:12
Subsystem:
networking [dsa], networking [general], ocelot ethernet switch driver, the rest · Maintainers:
Andrew Lunn, Vladimir Oltean, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Vladimir Oltean, Linus Torvalds
From: Vladimir Oltean <vladimir.oltean@nxp.com> There is one place where we cannot avoid accessing driver data, and that is 2-step PTP TX timestamping, since the switch wants us to provide a timestamp request ID through the injection header, which naturally must come from a sequence number kept by the driver (it is generated by the .port_txtstamp method prior to the tagger's xmit). However, since other drivers like dsa_loop do not claim PTP support anyway, the DSA_SKB_CB(skb)->clone will always be NULL anyway, so if we move all PTP-related dereferences of struct ocelot and struct ocelot_port into a separate function, we can effectively ensure that this is dead code when the ocelot tagger is attached to non-ocelot switches, and the stateful portion of the tagger is more self-contained. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> --- Changes in v2: None. net/dsa/tag_ocelot.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-)
diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c
index 8ce0b26f3520..fe00519229d7 100644
--- a/net/dsa/tag_ocelot.c
+++ b/net/dsa/tag_ocelot.c@@ -5,6 +5,25 @@ #include <soc/mscc/ocelot.h> #include "dsa_priv.h" +static void ocelot_xmit_ptp(struct dsa_port *dp, void *injection, + struct sk_buff *clone) +{ + struct ocelot *ocelot = dp->ds->priv; + struct ocelot_port *ocelot_port; + u64 rew_op; + + 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 + */ + if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) + rew_op |= clone->cb[0] << 3; + + ocelot_ifh_set_rew_op(injection, rew_op); +} + static struct sk_buff *ocelot_xmit(struct sk_buff *skb, struct net_device *netdev) {
@@ -29,17 +48,8 @@ static struct sk_buff *ocelot_xmit(struct sk_buff *skb, ocelot_ifh_set_qos_class(injection, skb->priority); /* TX timestamping was requested */ - if (clone) { - u64 rew_op = ocelot_port->ptp_cmd; - - /* Retrieve timestamp ID populated inside skb->cb[0] of the - * clone by ocelot_port_add_txtstamp_skb - */ - if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) - rew_op |= clone->cb[0] << 3; - - ocelot_ifh_set_rew_op(injection, rew_op); - } + if (clone) + ocelot_xmit_ptp(dp, injection, clone); return skb; }
--
2.25.1