net: vlan: rename NETIF_F_HW_VLAN_* feature flags to NETIF_F_HW_VLAN_CTAG_*
[linux-3.10.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 <linux/export.h>
6 #include "vlan.h"
7
8 bool vlan_do_receive(struct sk_buff **skbp)
9 {
10         struct sk_buff *skb = *skbp;
11         u16 vlan_id = skb->vlan_tci & VLAN_VID_MASK;
12         struct net_device *vlan_dev;
13         struct vlan_pcpu_stats *rx_stats;
14
15         vlan_dev = vlan_find_dev(skb->dev, vlan_id);
16         if (!vlan_dev)
17                 return false;
18
19         skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
20         if (unlikely(!skb))
21                 return false;
22
23         skb->dev = vlan_dev;
24         if (skb->pkt_type == PACKET_OTHERHOST) {
25                 /* Our lower layer thinks this is not local, let's make sure.
26                  * This allows the VLAN to have a different MAC than the
27                  * underlying device, and still route correctly. */
28                 if (ether_addr_equal(eth_hdr(skb)->h_dest, vlan_dev->dev_addr))
29                         skb->pkt_type = PACKET_HOST;
30         }
31
32         if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR)) {
33                 unsigned int offset = skb->data - skb_mac_header(skb);
34
35                 /*
36                  * vlan_insert_tag expect skb->data pointing to mac header.
37                  * So change skb->data before calling it and change back to
38                  * original position later
39                  */
40                 skb_push(skb, offset);
41                 skb = *skbp = vlan_insert_tag(skb, skb->vlan_tci);
42                 if (!skb)
43                         return false;
44                 skb_pull(skb, offset + VLAN_HLEN);
45                 skb_reset_mac_len(skb);
46         }
47
48         skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
49         skb->vlan_tci = 0;
50
51         rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
52
53         u64_stats_update_begin(&rx_stats->syncp);
54         rx_stats->rx_packets++;
55         rx_stats->rx_bytes += skb->len;
56         if (skb->pkt_type == PACKET_MULTICAST)
57                 rx_stats->rx_multicast++;
58         u64_stats_update_end(&rx_stats->syncp);
59
60         return true;
61 }
62
63 /* Must be invoked with rcu_read_lock. */
64 struct net_device *__vlan_find_dev_deep(struct net_device *dev,
65                                         u16 vlan_id)
66 {
67         struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
68
69         if (vlan_info) {
70                 return vlan_group_get_device(&vlan_info->grp, vlan_id);
71         } else {
72                 /*
73                  * Lower devices of master uppers (bonding, team) do not have
74                  * grp assigned to themselves. Grp is assigned to upper device
75                  * instead.
76                  */
77                 struct net_device *upper_dev;
78
79                 upper_dev = netdev_master_upper_dev_get_rcu(dev);
80                 if (upper_dev)
81                         return __vlan_find_dev_deep(upper_dev, vlan_id);
82         }
83
84         return NULL;
85 }
86 EXPORT_SYMBOL(__vlan_find_dev_deep);
87
88 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
89 {
90         return vlan_dev_priv(dev)->real_dev;
91 }
92 EXPORT_SYMBOL(vlan_dev_real_dev);
93
94 u16 vlan_dev_vlan_id(const struct net_device *dev)
95 {
96         return vlan_dev_priv(dev)->vlan_id;
97 }
98 EXPORT_SYMBOL(vlan_dev_vlan_id);
99
100 static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
101 {
102         if (skb_cow(skb, skb_headroom(skb)) < 0)
103                 return NULL;
104         memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN);
105         skb->mac_header += VLAN_HLEN;
106         return skb;
107 }
108
109 struct sk_buff *vlan_untag(struct sk_buff *skb)
110 {
111         struct vlan_hdr *vhdr;
112         u16 vlan_tci;
113
114         if (unlikely(vlan_tx_tag_present(skb))) {
115                 /* vlan_tci is already set-up so leave this for another time */
116                 return skb;
117         }
118
119         skb = skb_share_check(skb, GFP_ATOMIC);
120         if (unlikely(!skb))
121                 goto err_free;
122
123         if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
124                 goto err_free;
125
126         vhdr = (struct vlan_hdr *) skb->data;
127         vlan_tci = ntohs(vhdr->h_vlan_TCI);
128         __vlan_hwaccel_put_tag(skb, vlan_tci);
129
130         skb_pull_rcsum(skb, VLAN_HLEN);
131         vlan_set_encap_proto(skb, vhdr);
132
133         skb = vlan_reorder_header(skb);
134         if (unlikely(!skb))
135                 goto err_free;
136
137         skb_reset_network_header(skb);
138         skb_reset_transport_header(skb);
139         skb_reset_mac_len(skb);
140
141         return skb;
142
143 err_free:
144         kfree_skb(skb);
145         return NULL;
146 }
147 EXPORT_SYMBOL(vlan_untag);
148
149
150 /*
151  * vlan info and vid list
152  */
153
154 static void vlan_group_free(struct vlan_group *grp)
155 {
156         int i;
157
158         for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
159                 kfree(grp->vlan_devices_arrays[i]);
160 }
161
162 static void vlan_info_free(struct vlan_info *vlan_info)
163 {
164         vlan_group_free(&vlan_info->grp);
165         kfree(vlan_info);
166 }
167
168 static void vlan_info_rcu_free(struct rcu_head *rcu)
169 {
170         vlan_info_free(container_of(rcu, struct vlan_info, rcu));
171 }
172
173 static struct vlan_info *vlan_info_alloc(struct net_device *dev)
174 {
175         struct vlan_info *vlan_info;
176
177         vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
178         if (!vlan_info)
179                 return NULL;
180
181         vlan_info->real_dev = dev;
182         INIT_LIST_HEAD(&vlan_info->vid_list);
183         return vlan_info;
184 }
185
186 struct vlan_vid_info {
187         struct list_head list;
188         unsigned short vid;
189         int refcount;
190 };
191
192 static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
193                                                unsigned short vid)
194 {
195         struct vlan_vid_info *vid_info;
196
197         list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
198                 if (vid_info->vid == vid)
199                         return vid_info;
200         }
201         return NULL;
202 }
203
204 static struct vlan_vid_info *vlan_vid_info_alloc(unsigned short vid)
205 {
206         struct vlan_vid_info *vid_info;
207
208         vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
209         if (!vid_info)
210                 return NULL;
211         vid_info->vid = vid;
212
213         return vid_info;
214 }
215
216 static int __vlan_vid_add(struct vlan_info *vlan_info, unsigned short vid,
217                           struct vlan_vid_info **pvid_info)
218 {
219         struct net_device *dev = vlan_info->real_dev;
220         const struct net_device_ops *ops = dev->netdev_ops;
221         struct vlan_vid_info *vid_info;
222         int err;
223
224         vid_info = vlan_vid_info_alloc(vid);
225         if (!vid_info)
226                 return -ENOMEM;
227
228         if (dev->features & NETIF_F_HW_VLAN_CTAG_FILTER) {
229                 err =  ops->ndo_vlan_rx_add_vid(dev, vid);
230                 if (err) {
231                         kfree(vid_info);
232                         return err;
233                 }
234         }
235         list_add(&vid_info->list, &vlan_info->vid_list);
236         vlan_info->nr_vids++;
237         *pvid_info = vid_info;
238         return 0;
239 }
240
241 int vlan_vid_add(struct net_device *dev, unsigned short vid)
242 {
243         struct vlan_info *vlan_info;
244         struct vlan_vid_info *vid_info;
245         bool vlan_info_created = false;
246         int err;
247
248         ASSERT_RTNL();
249
250         vlan_info = rtnl_dereference(dev->vlan_info);
251         if (!vlan_info) {
252                 vlan_info = vlan_info_alloc(dev);
253                 if (!vlan_info)
254                         return -ENOMEM;
255                 vlan_info_created = true;
256         }
257         vid_info = vlan_vid_info_get(vlan_info, vid);
258         if (!vid_info) {
259                 err = __vlan_vid_add(vlan_info, vid, &vid_info);
260                 if (err)
261                         goto out_free_vlan_info;
262         }
263         vid_info->refcount++;
264
265         if (vlan_info_created)
266                 rcu_assign_pointer(dev->vlan_info, vlan_info);
267
268         return 0;
269
270 out_free_vlan_info:
271         if (vlan_info_created)
272                 kfree(vlan_info);
273         return err;
274 }
275 EXPORT_SYMBOL(vlan_vid_add);
276
277 static void __vlan_vid_del(struct vlan_info *vlan_info,
278                            struct vlan_vid_info *vid_info)
279 {
280         struct net_device *dev = vlan_info->real_dev;
281         const struct net_device_ops *ops = dev->netdev_ops;
282         unsigned short vid = vid_info->vid;
283         int err;
284
285         if (dev->features & NETIF_F_HW_VLAN_CTAG_FILTER) {
286                 err = ops->ndo_vlan_rx_kill_vid(dev, vid);
287                 if (err) {
288                         pr_warn("failed to kill vid %d for device %s\n",
289                                 vid, dev->name);
290                 }
291         }
292         list_del(&vid_info->list);
293         kfree(vid_info);
294         vlan_info->nr_vids--;
295 }
296
297 void vlan_vid_del(struct net_device *dev, unsigned short vid)
298 {
299         struct vlan_info *vlan_info;
300         struct vlan_vid_info *vid_info;
301
302         ASSERT_RTNL();
303
304         vlan_info = rtnl_dereference(dev->vlan_info);
305         if (!vlan_info)
306                 return;
307
308         vid_info = vlan_vid_info_get(vlan_info, vid);
309         if (!vid_info)
310                 return;
311         vid_info->refcount--;
312         if (vid_info->refcount == 0) {
313                 __vlan_vid_del(vlan_info, vid_info);
314                 if (vlan_info->nr_vids == 0) {
315                         RCU_INIT_POINTER(dev->vlan_info, NULL);
316                         call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
317                 }
318         }
319 }
320 EXPORT_SYMBOL(vlan_vid_del);
321
322 int vlan_vids_add_by_dev(struct net_device *dev,
323                          const struct net_device *by_dev)
324 {
325         struct vlan_vid_info *vid_info;
326         struct vlan_info *vlan_info;
327         int err;
328
329         ASSERT_RTNL();
330
331         vlan_info = rtnl_dereference(by_dev->vlan_info);
332         if (!vlan_info)
333                 return 0;
334
335         list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
336                 err = vlan_vid_add(dev, vid_info->vid);
337                 if (err)
338                         goto unwind;
339         }
340         return 0;
341
342 unwind:
343         list_for_each_entry_continue_reverse(vid_info,
344                                              &vlan_info->vid_list,
345                                              list) {
346                 vlan_vid_del(dev, vid_info->vid);
347         }
348
349         return err;
350 }
351 EXPORT_SYMBOL(vlan_vids_add_by_dev);
352
353 void vlan_vids_del_by_dev(struct net_device *dev,
354                           const struct net_device *by_dev)
355 {
356         struct vlan_vid_info *vid_info;
357         struct vlan_info *vlan_info;
358
359         ASSERT_RTNL();
360
361         vlan_info = rtnl_dereference(by_dev->vlan_info);
362         if (!vlan_info)
363                 return;
364
365         list_for_each_entry(vid_info, &vlan_info->vid_list, list)
366                 vlan_vid_del(dev, vid_info->vid);
367 }
368 EXPORT_SYMBOL(vlan_vids_del_by_dev);
369
370 bool vlan_uses_dev(const struct net_device *dev)
371 {
372         struct vlan_info *vlan_info;
373
374         ASSERT_RTNL();
375
376         vlan_info = rtnl_dereference(dev->vlan_info);
377         if (!vlan_info)
378                 return false;
379         return vlan_info->grp.nr_vlan_devs ? true : false;
380 }
381 EXPORT_SYMBOL(vlan_uses_dev);