linux/net/core/timestamping.c
Daniel Borkmann 164d8c6665 net: ptp: do not reimplement PTP/BPF classifier
There are currently pch_gbe, cpts, and ixp4xx_eth drivers that open-code
and reimplement a BPF classifier for the PTP protocol. Since all of them
effectively do the very same thing and load the very same PTP/BPF filter,
we can just consolidate that code by introducing ptp_classify_raw() in
the time-stamping core framework which can be used in drivers.

As drivers get initialized after bootstrapping the core networking
subsystem, they can make use of ptp_insns wrapped through
ptp_classify_raw(), which allows to simplify and remove PTP classifier
setup code in drivers.

Joint work with Alexei Starovoitov.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Richard Cochran <richard.cochran@omicron.at>
Cc: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-31 00:45:09 -04:00

153 lines
3.4 KiB
C

/*
* PTP 1588 clock support - support for timestamping in PHY devices
*
* Copyright (C) 2010 OMICRON electronics GmbH
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/errqueue.h>
#include <linux/phy.h>
#include <linux/ptp_classify.h>
#include <linux/skbuff.h>
#include <linux/export.h>
static struct sk_filter *ptp_insns __read_mostly;
unsigned int ptp_classify_raw(const struct sk_buff *skb)
{
return SK_RUN_FILTER(ptp_insns, skb);
}
EXPORT_SYMBOL_GPL(ptp_classify_raw);
static unsigned int classify(const struct sk_buff *skb)
{
if (likely(skb->dev && skb->dev->phydev &&
skb->dev->phydev->drv))
return ptp_classify_raw(skb);
else
return PTP_CLASS_NONE;
}
void skb_clone_tx_timestamp(struct sk_buff *skb)
{
struct phy_device *phydev;
struct sk_buff *clone;
struct sock *sk = skb->sk;
unsigned int type;
if (!sk)
return;
type = classify(skb);
switch (type) {
case PTP_CLASS_V1_IPV4:
case PTP_CLASS_V1_IPV6:
case PTP_CLASS_V2_IPV4:
case PTP_CLASS_V2_IPV6:
case PTP_CLASS_V2_L2:
case PTP_CLASS_V2_VLAN:
phydev = skb->dev->phydev;
if (likely(phydev->drv->txtstamp)) {
if (!atomic_inc_not_zero(&sk->sk_refcnt))
return;
clone = skb_clone(skb, GFP_ATOMIC);
if (!clone) {
sock_put(sk);
return;
}
clone->sk = sk;
phydev->drv->txtstamp(phydev, clone, type);
}
break;
default:
break;
}
}
EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
void skb_complete_tx_timestamp(struct sk_buff *skb,
struct skb_shared_hwtstamps *hwtstamps)
{
struct sock *sk = skb->sk;
struct sock_exterr_skb *serr;
int err;
if (!hwtstamps) {
sock_put(sk);
kfree_skb(skb);
return;
}
*skb_hwtstamps(skb) = *hwtstamps;
serr = SKB_EXT_ERR(skb);
memset(serr, 0, sizeof(*serr));
serr->ee.ee_errno = ENOMSG;
serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
skb->sk = NULL;
err = sock_queue_err_skb(sk, skb);
sock_put(sk);
if (err)
kfree_skb(skb);
}
EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp);
bool skb_defer_rx_timestamp(struct sk_buff *skb)
{
struct phy_device *phydev;
unsigned int type;
if (skb_headroom(skb) < ETH_HLEN)
return false;
__skb_push(skb, ETH_HLEN);
type = classify(skb);
__skb_pull(skb, ETH_HLEN);
switch (type) {
case PTP_CLASS_V1_IPV4:
case PTP_CLASS_V1_IPV6:
case PTP_CLASS_V2_IPV4:
case PTP_CLASS_V2_IPV6:
case PTP_CLASS_V2_L2:
case PTP_CLASS_V2_VLAN:
phydev = skb->dev->phydev;
if (likely(phydev->drv->rxtstamp))
return phydev->drv->rxtstamp(phydev, skb, type);
break;
default:
break;
}
return false;
}
EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);
void __init skb_timestamping_init(void)
{
static struct sock_filter ptp_filter[] = { PTP_FILTER };
struct sock_fprog ptp_prog = {
.len = ARRAY_SIZE(ptp_filter), .filter = ptp_filter,
};
BUG_ON(sk_unattached_filter_create(&ptp_insns, &ptp_prog));
}