filter: optimize sk_run_filter
[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(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                         clone = skb_clone(skb, GFP_ATOMIC);
61                         if (!clone)
62                                 return;
63                         clone->sk = sk;
64                         phydev->drv->txtstamp(phydev, clone, type);
65                 }
66                 break;
67         default:
68                 break;
69         }
70 }
71
72 void skb_complete_tx_timestamp(struct sk_buff *skb,
73                                struct skb_shared_hwtstamps *hwtstamps)
74 {
75         struct sock *sk = skb->sk;
76         struct sock_exterr_skb *serr;
77         int err;
78
79         if (!hwtstamps)
80                 return;
81
82         *skb_hwtstamps(skb) = *hwtstamps;
83         serr = SKB_EXT_ERR(skb);
84         memset(serr, 0, sizeof(*serr));
85         serr->ee.ee_errno = ENOMSG;
86         serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
87         skb->sk = NULL;
88         err = sock_queue_err_skb(sk, skb);
89         if (err)
90                 kfree_skb(skb);
91 }
92 EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp);
93
94 bool skb_defer_rx_timestamp(struct sk_buff *skb)
95 {
96         struct phy_device *phydev;
97         unsigned int type;
98
99         skb_push(skb, ETH_HLEN);
100
101         type = classify(skb);
102
103         skb_pull(skb, ETH_HLEN);
104
105         switch (type) {
106         case PTP_CLASS_V1_IPV4:
107         case PTP_CLASS_V1_IPV6:
108         case PTP_CLASS_V2_IPV4:
109         case PTP_CLASS_V2_IPV6:
110         case PTP_CLASS_V2_L2:
111         case PTP_CLASS_V2_VLAN:
112                 phydev = skb->dev->phydev;
113                 if (likely(phydev->drv->rxtstamp))
114                         return phydev->drv->rxtstamp(phydev, skb, type);
115                 break;
116         default:
117                 break;
118         }
119
120         return false;
121 }
122
123 void __init skb_timestamping_init(void)
124 {
125         BUG_ON(sk_chk_filter(ptp_filter, ARRAY_SIZE(ptp_filter)));
126 }