mqprio: Avoid panic if no options are provided
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / core / timestamping.c
blob82fb28857b647163b931c7f11294a4cae19e7bbc
1 /*
2 * PTP 1588 clock support - support for timestamping in PHY devices
4 * Copyright (C) 2010 OMICRON electronics GmbH
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.
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.
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.
20 #include <linux/errqueue.h>
21 #include <linux/phy.h>
22 #include <linux/ptp_classify.h>
23 #include <linux/skbuff.h>
25 static struct sock_filter ptp_filter[] = {
26 PTP_FILTER
29 static unsigned int classify(const struct sk_buff *skb)
31 if (likely(skb->dev &&
32 skb->dev->phydev &&
33 skb->dev->phydev->drv))
34 return sk_run_filter(skb, ptp_filter);
35 else
36 return PTP_CLASS_NONE;
39 void skb_clone_tx_timestamp(struct sk_buff *skb)
41 struct phy_device *phydev;
42 struct sk_buff *clone;
43 struct sock *sk = skb->sk;
44 unsigned int type;
46 if (!sk)
47 return;
49 type = classify(skb);
51 switch (type) {
52 case PTP_CLASS_V1_IPV4:
53 case PTP_CLASS_V1_IPV6:
54 case PTP_CLASS_V2_IPV4:
55 case PTP_CLASS_V2_IPV6:
56 case PTP_CLASS_V2_L2:
57 case PTP_CLASS_V2_VLAN:
58 phydev = skb->dev->phydev;
59 if (likely(phydev->drv->txtstamp)) {
60 if (!atomic_inc_not_zero(&sk->sk_refcnt))
61 return;
62 clone = skb_clone(skb, GFP_ATOMIC);
63 if (!clone) {
64 sock_put(sk);
65 return;
67 clone->sk = sk;
68 phydev->drv->txtstamp(phydev, clone, type);
70 break;
71 default:
72 break;
75 EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
77 void skb_complete_tx_timestamp(struct sk_buff *skb,
78 struct skb_shared_hwtstamps *hwtstamps)
80 struct sock *sk = skb->sk;
81 struct sock_exterr_skb *serr;
82 int err;
84 if (!hwtstamps) {
85 sock_put(sk);
86 kfree_skb(skb);
87 return;
90 *skb_hwtstamps(skb) = *hwtstamps;
91 serr = SKB_EXT_ERR(skb);
92 memset(serr, 0, sizeof(*serr));
93 serr->ee.ee_errno = ENOMSG;
94 serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
95 skb->sk = NULL;
96 err = sock_queue_err_skb(sk, skb);
97 sock_put(sk);
98 if (err)
99 kfree_skb(skb);
101 EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp);
103 bool skb_defer_rx_timestamp(struct sk_buff *skb)
105 struct phy_device *phydev;
106 unsigned int type;
108 if (skb_headroom(skb) < ETH_HLEN)
109 return false;
110 __skb_push(skb, ETH_HLEN);
112 type = classify(skb);
114 __skb_pull(skb, ETH_HLEN);
116 switch (type) {
117 case PTP_CLASS_V1_IPV4:
118 case PTP_CLASS_V1_IPV6:
119 case PTP_CLASS_V2_IPV4:
120 case PTP_CLASS_V2_IPV6:
121 case PTP_CLASS_V2_L2:
122 case PTP_CLASS_V2_VLAN:
123 phydev = skb->dev->phydev;
124 if (likely(phydev->drv->rxtstamp))
125 return phydev->drv->rxtstamp(phydev, skb, type);
126 break;
127 default:
128 break;
131 return false;
133 EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);
135 void __init skb_timestamping_init(void)
137 BUG_ON(sk_chk_filter(ptp_filter, ARRAY_SIZE(ptp_filter)));