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->mii_ts))
  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 mii_timestamper *mii_ts;
  25         struct sk_buff *clone;
  26         unsigned int type;
  27
  28         if (!skb->sk || !skb->dev ||
  29             !phy_is_default_hwtstamp(skb->dev->phydev))
  30                 return;
  31
  32         type = classify(skb);
  33         if (type == PTP_CLASS_NONE)
  34                 return;
  35
  36         mii_ts = skb->dev->phydev->mii_ts;
  37         if (likely(mii_ts->txtstamp)) {
  38                 clone = skb_clone_sk(skb);
  39                 if (!clone)
  40                         return;
  41                 mii_ts->txtstamp(mii_ts, clone, type);
  42         }
  43 }
  44 EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
  45
  46 bool skb_defer_rx_timestamp(struct sk_buff *skb)
  47 {
  48         struct mii_timestamper *mii_ts;
  49         unsigned int type;
  50
  51         if (!skb->dev || !phy_is_default_hwtstamp(skb->dev->phydev))
  52                 return false;
  53
  54         if (skb_headroom(skb) < ETH_HLEN)
  55                 return false;
  56
  57         __skb_push(skb, ETH_HLEN);
  58
  59         type = ptp_classify_raw(skb);
  60
  61         __skb_pull(skb, ETH_HLEN);
  62
  63         if (type == PTP_CLASS_NONE)
  64                 return false;
  65
  66         mii_ts = skb->dev->phydev->mii_ts;
  67         if (likely(mii_ts->rxtstamp))
  68                 return mii_ts->rxtstamp(mii_ts, skb, type);
  69
  70         return false;
  71 }
  72 EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);