net/core/timestamping.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * PTP 1588 clock support - support for timestamping in PHY devices
   4  *
   5  * Copyright (C) 2010 OMICRON electronics GmbH
   6  */
   7 #include <linux/errqueue.h>
   8 #include <linux/phy.h>
   9 #include <linux/ptp_classify.h>
  10 #include <linux/skbuff.h>
  11 #include <linux/export.h>
  12
  13 static unsigned int classify(const struct sk_buff *skb)
  14 {
  15         if (likely(skb->dev && skb->dev->phydev &&
  16                    skb->dev->phydev->drv))
  17                 return ptp_classify_raw(skb);
  18         else
  19                 return PTP_CLASS_NONE;
  20 }
  21
  22 void skb_clone_tx_timestamp(struct sk_buff *skb)
  23 {
  24         struct phy_device *phydev;
  25         struct sk_buff *clone;
  26         unsigned int type;
  27
  28         if (!skb->sk)
  29                 return;
  30
  31         type = classify(skb);
  32         if (type == PTP_CLASS_NONE)
  33                 return;
  34
  35         phydev = skb->dev->phydev;
  36         if (likely(phydev->drv->txtstamp)) {
  37                 clone = skb_clone_sk(skb);
  38                 if (!clone)
  39                         return;
  40                 phydev->drv->txtstamp(phydev, clone, type);
  41         }
  42 }
  43 EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
  44
  45 bool skb_defer_rx_timestamp(struct sk_buff *skb)
  46 {
  47         struct phy_device *phydev;
  48         unsigned int type;
  49
  50         if (!skb->dev || !skb->dev->phydev || !skb->dev->phydev->drv)
  51                 return false;
  52
  53         if (skb_headroom(skb) < ETH_HLEN)
  54                 return false;
  55
  56         __skb_push(skb, ETH_HLEN);
  57
  58         type = ptp_classify_raw(skb);
  59
  60         __skb_pull(skb, ETH_HLEN);
  61
  62         if (type == PTP_CLASS_NONE)
  63                 return false;
  64
  65         phydev = skb->dev->phydev;
  66         if (likely(phydev->drv->rxtstamp))
  67                 return phydev->drv->rxtstamp(phydev, skb, type);
  68
  69         return false;
  70 }
  71 EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);