arm: tegra: enterprise: Controls for 3d barrier
[linux-2.6.git] / 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
25 static struct sock_filter ptp_filter[] = {
26         PTP_FILTER
27 };
28
29 static unsigned int classify(const struct sk_buff *skb)
30 {
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;
37 }
38
39 void skb_clone_tx_timestamp(struct sk_buff *skb)
40 {
41         struct phy_device *phydev;
42         struct sk_buff *clone;
43         struct sock *sk = skb->sk;
44         unsigned int type;
45
46         if (!sk)
47                 return;
48
49         type = classify(skb);
50
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;
66                         }
67                         clone->sk = sk;
68                         phydev->drv->txtstamp(phydev, clone, type);
69                 }
70                 break;
71         default:
72                 break;
73         }
74 }
75 EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
76
77 void skb_complete_tx_timestamp(struct sk_buff *skb,
78                                struct skb_shared_hwtstamps *hwtstamps)
79 {
80         struct sock *sk = skb->sk;
81         struct sock_exterr_skb *serr;
82         int err;
83
84         if (!hwtstamps) {
85                 sock_put(sk);
86                 kfree_skb(skb);
87                 return;
88         }
89
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);
100 }
101 EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp);
102
103 bool skb_defer_rx_timestamp(struct sk_buff *skb)
104 {
105         struct phy_device *phydev;
106         unsigned int type;
107
108         if (skb_headroom(skb) < ETH_HLEN)
109                 return false;
110         __skb_push(skb, ETH_HLEN);
111
112         type = classify(skb);
113
114         __skb_pull(skb, ETH_HLEN);
115
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;
129         }
130
131         return false;
132 }
133 EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);
134
135 void __init skb_timestamping_init(void)
136 {
137         BUG_ON(sk_chk_filter(ptp_filter, ARRAY_SIZE(ptp_filter)));
138 }