kvm tools, setup: Create private directory
[linux-2.6/next.git] / net / 8021q / vlan_core.c
blobfcc684678af67e644c6cc043dacee9f4159fb5b4
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"
7 bool vlan_do_receive(struct sk_buff **skbp)
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;
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;
21 skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
22 if (unlikely(!skb))
23 return false;
25 skb->dev = vlan_dev;
26 if (skb->pkt_type == PACKET_OTHERHOST) {
27 /* Our lower layer thinks this is not local, let's make sure.
28 * This allows the VLAN to have a different MAC than the
29 * underlying device, and still route correctly. */
30 if (!compare_ether_addr(eth_hdr(skb)->h_dest,
31 vlan_dev->dev_addr))
32 skb->pkt_type = PACKET_HOST;
35 if (!(vlan_dev_info(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR)) {
36 unsigned int offset = skb->data - skb_mac_header(skb);
39 * vlan_insert_tag expect skb->data pointing to mac header.
40 * So change skb->data before calling it and change back to
41 * original position later
43 skb_push(skb, offset);
44 skb = *skbp = vlan_insert_tag(skb, skb->vlan_tci);
45 if (!skb)
46 return false;
47 skb_pull(skb, offset + VLAN_HLEN);
48 skb_reset_mac_len(skb);
51 skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
52 skb->vlan_tci = 0;
54 rx_stats = this_cpu_ptr(vlan_dev_info(vlan_dev)->vlan_pcpu_stats);
56 u64_stats_update_begin(&rx_stats->syncp);
57 rx_stats->rx_packets++;
58 rx_stats->rx_bytes += skb->len;
59 if (skb->pkt_type == PACKET_MULTICAST)
60 rx_stats->rx_multicast++;
61 u64_stats_update_end(&rx_stats->syncp);
63 return true;
66 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
68 return vlan_dev_info(dev)->real_dev;
70 EXPORT_SYMBOL(vlan_dev_real_dev);
72 u16 vlan_dev_vlan_id(const struct net_device *dev)
74 return vlan_dev_info(dev)->vlan_id;
76 EXPORT_SYMBOL(vlan_dev_vlan_id);
78 /* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
79 int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
80 u16 vlan_tci, int polling)
82 __vlan_hwaccel_put_tag(skb, vlan_tci);
83 return polling ? netif_receive_skb(skb) : netif_rx(skb);
85 EXPORT_SYMBOL(__vlan_hwaccel_rx);
87 gro_result_t vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
88 unsigned int vlan_tci, struct sk_buff *skb)
90 __vlan_hwaccel_put_tag(skb, vlan_tci);
91 return napi_gro_receive(napi, skb);
93 EXPORT_SYMBOL(vlan_gro_receive);
95 gro_result_t vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
96 unsigned int vlan_tci)
98 __vlan_hwaccel_put_tag(napi->skb, vlan_tci);
99 return napi_gro_frags(napi);
101 EXPORT_SYMBOL(vlan_gro_frags);
103 static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
105 if (skb_cow(skb, skb_headroom(skb)) < 0)
106 return NULL;
107 memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN);
108 skb->mac_header += VLAN_HLEN;
109 skb_reset_mac_len(skb);
110 return skb;
113 static void vlan_set_encap_proto(struct sk_buff *skb, struct vlan_hdr *vhdr)
115 __be16 proto;
116 unsigned char *rawp;
119 * Was a VLAN packet, grab the encapsulated protocol, which the layer
120 * three protocols care about.
123 proto = vhdr->h_vlan_encapsulated_proto;
124 if (ntohs(proto) >= 1536) {
125 skb->protocol = proto;
126 return;
129 rawp = skb->data;
130 if (*(unsigned short *) rawp == 0xFFFF)
132 * This is a magic hack to spot IPX packets. Older Novell
133 * breaks the protocol design and runs IPX over 802.3 without
134 * an 802.2 LLC layer. We look for FFFF which isn't a used
135 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
136 * but does for the rest.
138 skb->protocol = htons(ETH_P_802_3);
139 else
141 * Real 802.2 LLC
143 skb->protocol = htons(ETH_P_802_2);
146 struct sk_buff *vlan_untag(struct sk_buff *skb)
148 struct vlan_hdr *vhdr;
149 u16 vlan_tci;
151 if (unlikely(vlan_tx_tag_present(skb))) {
152 /* vlan_tci is already set-up so leave this for another time */
153 return skb;
156 skb = skb_share_check(skb, GFP_ATOMIC);
157 if (unlikely(!skb))
158 goto err_free;
160 if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
161 goto err_free;
163 vhdr = (struct vlan_hdr *) skb->data;
164 vlan_tci = ntohs(vhdr->h_vlan_TCI);
165 __vlan_hwaccel_put_tag(skb, vlan_tci);
167 skb_pull_rcsum(skb, VLAN_HLEN);
168 vlan_set_encap_proto(skb, vhdr);
170 skb = vlan_reorder_header(skb);
171 if (unlikely(!skb))
172 goto err_free;
174 return skb;
176 err_free:
177 kfree_skb(skb);
178 return NULL;