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
26 static struct sock_filter ptp_filter[] = {
27 PTP_FILTER
28 };
29
classify(const struct sk_buff * skb)30 static unsigned int classify(const struct sk_buff *skb)
31 {
32 if (likely(skb->dev &&
33 skb->dev->phydev &&
34 skb->dev->phydev->drv))
35 return sk_run_filter(skb, ptp_filter);
36 else
37 return PTP_CLASS_NONE;
38 }
39
skb_clone_tx_timestamp(struct sk_buff * skb)40 void skb_clone_tx_timestamp(struct sk_buff *skb)
41 {
42 struct phy_device *phydev;
43 struct sk_buff *clone;
44 struct sock *sk = skb->sk;
45 unsigned int type;
46
47 if (!sk)
48 return;
49
50 type = classify(skb);
51
52 switch (type) {
53 case PTP_CLASS_V1_IPV4:
54 case PTP_CLASS_V1_IPV6:
55 case PTP_CLASS_V2_IPV4:
56 case PTP_CLASS_V2_IPV6:
57 case PTP_CLASS_V2_L2:
58 case PTP_CLASS_V2_VLAN:
59 phydev = skb->dev->phydev;
60 if (likely(phydev->drv->txtstamp)) {
61 if (!atomic_inc_not_zero(&sk->sk_refcnt))
62 return;
63 clone = skb_clone(skb, GFP_ATOMIC);
64 if (!clone) {
65 sock_put(sk);
66 return;
67 }
68 clone->sk = sk;
69 phydev->drv->txtstamp(phydev, clone, type);
70 }
71 break;
72 default:
73 break;
74 }
75 }
76 EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
77
skb_complete_tx_timestamp(struct sk_buff * skb,struct skb_shared_hwtstamps * hwtstamps)78 void skb_complete_tx_timestamp(struct sk_buff *skb,
79 struct skb_shared_hwtstamps *hwtstamps)
80 {
81 struct sock *sk = skb->sk;
82 struct sock_exterr_skb *serr;
83 int err;
84
85 if (!hwtstamps) {
86 sock_put(sk);
87 kfree_skb(skb);
88 return;
89 }
90
91 *skb_hwtstamps(skb) = *hwtstamps;
92 serr = SKB_EXT_ERR(skb);
93 memset(serr, 0, sizeof(*serr));
94 serr->ee.ee_errno = ENOMSG;
95 serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
96 skb->sk = NULL;
97 err = sock_queue_err_skb(sk, skb);
98 sock_put(sk);
99 if (err)
100 kfree_skb(skb);
101 }
102 EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp);
103
skb_defer_rx_timestamp(struct sk_buff * skb)104 bool skb_defer_rx_timestamp(struct sk_buff *skb)
105 {
106 struct phy_device *phydev;
107 unsigned int type;
108
109 if (skb_headroom(skb) < ETH_HLEN)
110 return false;
111 __skb_push(skb, ETH_HLEN);
112
113 type = classify(skb);
114
115 __skb_pull(skb, ETH_HLEN);
116
117 switch (type) {
118 case PTP_CLASS_V1_IPV4:
119 case PTP_CLASS_V1_IPV6:
120 case PTP_CLASS_V2_IPV4:
121 case PTP_CLASS_V2_IPV6:
122 case PTP_CLASS_V2_L2:
123 case PTP_CLASS_V2_VLAN:
124 phydev = skb->dev->phydev;
125 if (likely(phydev->drv->rxtstamp))
126 return phydev->drv->rxtstamp(phydev, skb, type);
127 break;
128 default:
129 break;
130 }
131
132 return false;
133 }
134 EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);
135
skb_timestamping_init(void)136 void __init skb_timestamping_init(void)
137 {
138 BUG_ON(sk_chk_filter(ptp_filter, ARRAY_SIZE(ptp_filter)));
139 }
140