[media] v4l2-subdev.h: remove unused s_mode tuner op
[linux-2.6.git] / net / 8021q / vlan_core.c
1 #include <linux/skbuff.h>
2 #include <linux/netdevice.h>
3 #include <linux/if_vlan.h>
4 #include <linux/netpoll.h>
5 #include "vlan.h"
6
7 bool vlan_do_receive(struct sk_buff **skbp)
8 {
9         struct sk_buff *skb = *skbp;
10         u16 vlan_id = skb->vlan_tci & VLAN_VID_MASK;
11         struct net_device *vlan_dev;
12         struct vlan_pcpu_stats *rx_stats;
13
14         vlan_dev = vlan_find_dev(skb->dev, vlan_id);
15         if (!vlan_dev) {
16                 if (vlan_id)
17                         skb->pkt_type = PACKET_OTHERHOST;
18                 return false;
19         }
20
21         skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
22         if (unlikely(!skb))
23                 return false;
24
25         skb->dev = vlan_dev;
26         skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
27         skb->vlan_tci = 0;
28
29         rx_stats = this_cpu_ptr(vlan_dev_info(vlan_dev)->vlan_pcpu_stats);
30
31         u64_stats_update_begin(&rx_stats->syncp);
32         rx_stats->rx_packets++;
33         rx_stats->rx_bytes += skb->len;
34
35         switch (skb->pkt_type) {
36         case PACKET_BROADCAST:
37                 break;
38         case PACKET_MULTICAST:
39                 rx_stats->rx_multicast++;
40                 break;
41         case PACKET_OTHERHOST:
42                 /* Our lower layer thinks this is not local, let's make sure.
43                  * This allows the VLAN to have a different MAC than the
44                  * underlying device, and still route correctly. */
45                 if (!compare_ether_addr(eth_hdr(skb)->h_dest,
46                                         vlan_dev->dev_addr))
47                         skb->pkt_type = PACKET_HOST;
48                 break;
49         }
50         u64_stats_update_end(&rx_stats->syncp);
51
52         return true;
53 }
54
55 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
56 {
57         return vlan_dev_info(dev)->real_dev;
58 }
59 EXPORT_SYMBOL(vlan_dev_real_dev);
60
61 u16 vlan_dev_vlan_id(const struct net_device *dev)
62 {
63         return vlan_dev_info(dev)->vlan_id;
64 }
65 EXPORT_SYMBOL(vlan_dev_vlan_id);
66
67 /* VLAN rx hw acceleration helper.  This acts like netif_{rx,receive_skb}(). */
68 int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
69                       u16 vlan_tci, int polling)
70 {
71         __vlan_hwaccel_put_tag(skb, vlan_tci);
72         return polling ? netif_receive_skb(skb) : netif_rx(skb);
73 }
74 EXPORT_SYMBOL(__vlan_hwaccel_rx);
75
76 gro_result_t vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
77                               unsigned int vlan_tci, struct sk_buff *skb)
78 {
79         __vlan_hwaccel_put_tag(skb, vlan_tci);
80         return napi_gro_receive(napi, skb);
81 }
82 EXPORT_SYMBOL(vlan_gro_receive);
83
84 gro_result_t vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
85                             unsigned int vlan_tci)
86 {
87         __vlan_hwaccel_put_tag(napi->skb, vlan_tci);
88         return napi_gro_frags(napi);
89 }
90 EXPORT_SYMBOL(vlan_gro_frags);
91
92 static struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
93 {
94         if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
95                 if (skb_cow(skb, skb_headroom(skb)) < 0)
96                         skb = NULL;
97                 if (skb) {
98                         /* Lifted from Gleb's VLAN code... */
99                         memmove(skb->data - ETH_HLEN,
100                                 skb->data - VLAN_ETH_HLEN, 12);
101                         skb->mac_header += VLAN_HLEN;
102                 }
103         }
104         return skb;
105 }
106
107 static void vlan_set_encap_proto(struct sk_buff *skb, struct vlan_hdr *vhdr)
108 {
109         __be16 proto;
110         unsigned char *rawp;
111
112         /*
113          * Was a VLAN packet, grab the encapsulated protocol, which the layer
114          * three protocols care about.
115          */
116
117         proto = vhdr->h_vlan_encapsulated_proto;
118         if (ntohs(proto) >= 1536) {
119                 skb->protocol = proto;
120                 return;
121         }
122
123         rawp = skb->data;
124         if (*(unsigned short *) rawp == 0xFFFF)
125                 /*
126                  * This is a magic hack to spot IPX packets. Older Novell
127                  * breaks the protocol design and runs IPX over 802.3 without
128                  * an 802.2 LLC layer. We look for FFFF which isn't a used
129                  * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
130                  * but does for the rest.
131                  */
132                 skb->protocol = htons(ETH_P_802_3);
133         else
134                 /*
135                  * Real 802.2 LLC
136                  */
137                 skb->protocol = htons(ETH_P_802_2);
138 }
139
140 struct sk_buff *vlan_untag(struct sk_buff *skb)
141 {
142         struct vlan_hdr *vhdr;
143         u16 vlan_tci;
144
145         if (unlikely(vlan_tx_tag_present(skb))) {
146                 /* vlan_tci is already set-up so leave this for another time */
147                 return skb;
148         }
149
150         skb = skb_share_check(skb, GFP_ATOMIC);
151         if (unlikely(!skb))
152                 goto err_free;
153
154         if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
155                 goto err_free;
156
157         vhdr = (struct vlan_hdr *) skb->data;
158         vlan_tci = ntohs(vhdr->h_vlan_TCI);
159         __vlan_hwaccel_put_tag(skb, vlan_tci);
160
161         skb_pull_rcsum(skb, VLAN_HLEN);
162         vlan_set_encap_proto(skb, vhdr);
163
164         skb = vlan_check_reorder_header(skb);
165         if (unlikely(!skb))
166                 goto err_free;
167
168         return skb;
169
170 err_free:
171         kfree_skb(skb);
172         return NULL;
173 }