LXR linux/net/core/timestamping.c

   1/*
   2 * PTP 1588 clock support - support for timestamping in PHY devices
   3 *
   4 * Copyright (C) 2010 OMICRON electronics GmbH
   5 *
   6 *  This program is free software; you can redistribute it and/or modify
   7 *  it under the terms of the GNU General Public License as published by
   8 *  the Free Software Foundation; either version 2 of the License, or
   9 *  (at your option) any later version.
  10 *
  11 *  This program is distributed in the hope that it will be useful,
  12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 *  GNU General Public License for more details.
  15 *
  16 *  You should have received a copy of the GNU General Public License
  17 *  along with this program; if not, write to the Free Software
  18 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20#include <linux/errqueue.h>
  21#include <linux/phy.h>
  22#include <linux/ptp_classify.h>
  23#include <linux/skbuff.h>
  24#include <linux/export.h>
  25
  26static unsigned int classify(const struct sk_buff *skb)
  27{
  28        if (likely(skb->dev && skb->dev->phydev &&
  29                   skb->dev->phydev->drv))
  30                return ptp_classify_raw(skb);
  31        else
  32                return PTP_CLASS_NONE;
  33}
  34
  35void skb_clone_tx_timestamp(struct sk_buff *skb)
  36{
  37        struct phy_device *phydev;
  38        struct sk_buff *clone;
  39        unsigned int type;
  40
  41        if (!skb->sk)
  42                return;
  43
  44        type = classify(skb);
  45        if (type == PTP_CLASS_NONE)
  46                return;
  47
  48        phydev = skb->dev->phydev;
  49        if (likely(phydev->drv->txtstamp)) {
  50                clone = skb_clone_sk(skb);
  51                if (!clone)
  52                        return;
  53                phydev->drv->txtstamp(phydev, clone, type);
  54        }
  55}
  56EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
  57
  58bool skb_defer_rx_timestamp(struct sk_buff *skb)
  59{
  60        struct phy_device *phydev;
  61        unsigned int type;
  62
  63        if (!skb->dev || !skb->dev->phydev || !skb->dev->phydev->drv)
  64                return false;
  65
  66        if (skb_headroom(skb) < ETH_HLEN)
  67                return false;
  68
  69        __skb_push(skb, ETH_HLEN);
  70
  71        type = ptp_classify_raw(skb);
  72
  73        __skb_pull(skb, ETH_HLEN);
  74
  75        if (type == PTP_CLASS_NONE)
  76                return false;
  77
  78        phydev = skb->dev->phydev;
  79        if (likely(phydev->drv->rxtstamp))
  80                return phydev->drv->rxtstamp(phydev, skb, type);
  81
  82        return false;
  83}
  84EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);
  85