[SK_BUFF]: Use the helpers to get the layer header pointer
[linux-2.6/mini2440.git] / include / linux / if_vlan.h
blob544490d9d0bdfed269746ba7d7839e972f7cac1e
1 /*
2 * VLAN An implementation of 802.1Q VLAN tagging.
4 * Authors: Ben Greear <greearb@candelatech.com>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
13 #ifndef _LINUX_IF_VLAN_H_
14 #define _LINUX_IF_VLAN_H_
16 #ifdef __KERNEL__
18 /* externally defined structs */
19 struct vlan_group;
20 struct net_device;
21 struct packet_type;
22 struct vlan_collection;
23 struct vlan_dev_info;
24 struct hlist_node;
26 #include <linux/netdevice.h>
27 #include <linux/etherdevice.h>
29 #define VLAN_HLEN 4 /* The additional bytes (on top of the Ethernet header)
30 * that VLAN requires.
32 #define VLAN_ETH_ALEN 6 /* Octets in one ethernet addr */
33 #define VLAN_ETH_HLEN 18 /* Total octets in header. */
34 #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */
37 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
39 #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */
40 #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */
42 struct vlan_ethhdr {
43 unsigned char h_dest[ETH_ALEN]; /* destination eth addr */
44 unsigned char h_source[ETH_ALEN]; /* source ether addr */
45 __be16 h_vlan_proto; /* Should always be 0x8100 */
46 __be16 h_vlan_TCI; /* Encapsulates priority and VLAN ID */
47 __be16 h_vlan_encapsulated_proto; /* packet type ID field (or len) */
50 #include <linux/skbuff.h>
52 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
54 return (struct vlan_ethhdr *)skb_mac_header(skb);
57 struct vlan_hdr {
58 __be16 h_vlan_TCI; /* Encapsulates priority and VLAN ID */
59 __be16 h_vlan_encapsulated_proto; /* packet type ID field (or len) */
62 #define VLAN_VID_MASK 0xfff
64 /* found in socket.c */
65 extern void vlan_ioctl_set(int (*hook)(void __user *));
67 #define VLAN_NAME "vlan"
69 /* if this changes, algorithm will have to be reworked because this
70 * depends on completely exhausting the VLAN identifier space. Thus
71 * it gives constant time look-up, but in many cases it wastes memory.
73 #define VLAN_GROUP_ARRAY_LEN 4096
74 #define VLAN_GROUP_ARRAY_SPLIT_PARTS 8
75 #define VLAN_GROUP_ARRAY_PART_LEN (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS)
77 struct vlan_group {
78 int real_dev_ifindex; /* The ifindex of the ethernet(like) device the vlan is attached to. */
79 struct hlist_node hlist; /* linked list */
80 struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS];
81 struct rcu_head rcu;
84 static inline struct net_device *vlan_group_get_device(struct vlan_group *vg, int vlan_id)
86 struct net_device **array;
87 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
88 return array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN];
91 static inline void vlan_group_set_device(struct vlan_group *vg, int vlan_id,
92 struct net_device *dev)
94 struct net_device **array;
95 if (!vg)
96 return;
97 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
98 array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev;
101 struct vlan_priority_tci_mapping {
102 unsigned long priority;
103 unsigned short vlan_qos; /* This should be shifted when first set, so we only do it
104 * at provisioning time.
105 * ((skb->priority << 13) & 0xE000)
107 struct vlan_priority_tci_mapping *next;
110 /* Holds information that makes sense if this device is a VLAN device. */
111 struct vlan_dev_info {
112 /** This will be the mapping that correlates skb->priority to
113 * 3 bits of VLAN QOS tags...
115 unsigned long ingress_priority_map[8];
116 struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */
118 unsigned short vlan_id; /* The VLAN Identifier for this interface. */
119 unsigned short flags; /* (1 << 0) re_order_header This option will cause the
120 * VLAN code to move around the ethernet header on
121 * ingress to make the skb look **exactly** like it
122 * came in from an ethernet port. This destroys some of
123 * the VLAN information in the skb, but it fixes programs
124 * like DHCP that use packet-filtering and don't understand
125 * 802.1Q
127 struct dev_mc_list *old_mc_list; /* old multi-cast list for the VLAN interface..
128 * we save this so we can tell what changes were
129 * made, in order to feed the right changes down
130 * to the real hardware...
132 int old_allmulti; /* similar to above. */
133 int old_promiscuity; /* similar to above. */
134 struct net_device *real_dev; /* the underlying device/interface */
135 struct proc_dir_entry *dent; /* Holds the proc data */
136 unsigned long cnt_inc_headroom_on_tx; /* How many times did we have to grow the skb on TX. */
137 unsigned long cnt_encap_on_xmit; /* How many times did we have to encapsulate the skb on TX. */
138 struct net_device_stats dev_stats; /* Device stats (rx-bytes, tx-pkts, etc...) */
141 #define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))
143 /* inline functions */
145 static inline struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
147 return &(VLAN_DEV_INFO(dev)->dev_stats);
150 static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
151 unsigned short vlan_tag)
153 struct vlan_dev_info *vip = VLAN_DEV_INFO(dev);
155 return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
158 /* VLAN tx hw acceleration helpers. */
159 struct vlan_skb_tx_cookie {
160 u32 magic;
161 u32 vlan_tag;
164 #define VLAN_TX_COOKIE_MAGIC 0x564c414e /* "VLAN" in ascii. */
165 #define VLAN_TX_SKB_CB(__skb) ((struct vlan_skb_tx_cookie *)&((__skb)->cb[0]))
166 #define vlan_tx_tag_present(__skb) \
167 (VLAN_TX_SKB_CB(__skb)->magic == VLAN_TX_COOKIE_MAGIC)
168 #define vlan_tx_tag_get(__skb) (VLAN_TX_SKB_CB(__skb)->vlan_tag)
170 /* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
171 static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
172 struct vlan_group *grp,
173 unsigned short vlan_tag, int polling)
175 struct net_device_stats *stats;
177 if (skb_bond_should_drop(skb)) {
178 dev_kfree_skb_any(skb);
179 return NET_RX_DROP;
182 skb->dev = vlan_group_get_device(grp, vlan_tag & VLAN_VID_MASK);
183 if (skb->dev == NULL) {
184 dev_kfree_skb_any(skb);
186 /* Not NET_RX_DROP, this is not being dropped
187 * due to congestion.
189 return 0;
192 skb->dev->last_rx = jiffies;
194 stats = vlan_dev_get_stats(skb->dev);
195 stats->rx_packets++;
196 stats->rx_bytes += skb->len;
198 skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
199 switch (skb->pkt_type) {
200 case PACKET_BROADCAST:
201 break;
203 case PACKET_MULTICAST:
204 stats->multicast++;
205 break;
207 case PACKET_OTHERHOST:
208 /* Our lower layer thinks this is not local, let's make sure.
209 * This allows the VLAN to have a different MAC than the underlying
210 * device, and still route correctly.
212 if (!compare_ether_addr(eth_hdr(skb)->h_dest,
213 skb->dev->dev_addr))
214 skb->pkt_type = PACKET_HOST;
215 break;
218 return (polling ? netif_receive_skb(skb) : netif_rx(skb));
221 static inline int vlan_hwaccel_rx(struct sk_buff *skb,
222 struct vlan_group *grp,
223 unsigned short vlan_tag)
225 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
228 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
229 struct vlan_group *grp,
230 unsigned short vlan_tag)
232 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
236 * __vlan_put_tag - regular VLAN tag inserting
237 * @skb: skbuff to tag
238 * @tag: VLAN tag to insert
240 * Inserts the VLAN tag into @skb as part of the payload
241 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
243 * Following the skb_unshare() example, in case of error, the calling function
244 * doesn't have to worry about freeing the original skb.
246 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, unsigned short tag)
248 struct vlan_ethhdr *veth;
250 if (skb_headroom(skb) < VLAN_HLEN) {
251 struct sk_buff *sk_tmp = skb;
252 skb = skb_realloc_headroom(sk_tmp, VLAN_HLEN);
253 kfree_skb(sk_tmp);
254 if (!skb) {
255 printk(KERN_ERR "vlan: failed to realloc headroom\n");
256 return NULL;
258 } else {
259 skb = skb_unshare(skb, GFP_ATOMIC);
260 if (!skb) {
261 printk(KERN_ERR "vlan: failed to unshare skbuff\n");
262 return NULL;
266 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
268 /* Move the mac addresses to the beginning of the new header. */
269 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
271 /* first, the ethernet type */
272 veth->h_vlan_proto = __constant_htons(ETH_P_8021Q);
274 /* now, the tag */
275 veth->h_vlan_TCI = htons(tag);
277 skb->protocol = __constant_htons(ETH_P_8021Q);
278 skb->mac.raw -= VLAN_HLEN;
279 skb->nh.raw -= VLAN_HLEN;
281 return skb;
285 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
286 * @skb: skbuff to tag
287 * @tag: VLAN tag to insert
289 * Puts the VLAN tag in @skb->cb[] and lets the device do the rest
291 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, unsigned short tag)
293 struct vlan_skb_tx_cookie *cookie;
295 cookie = VLAN_TX_SKB_CB(skb);
296 cookie->magic = VLAN_TX_COOKIE_MAGIC;
297 cookie->vlan_tag = tag;
299 return skb;
302 #define HAVE_VLAN_PUT_TAG
305 * vlan_put_tag - inserts VLAN tag according to device features
306 * @skb: skbuff to tag
307 * @tag: VLAN tag to insert
309 * Assumes skb->dev is the target that will xmit this frame.
310 * Returns a VLAN tagged skb.
312 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, unsigned short tag)
314 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
315 return __vlan_hwaccel_put_tag(skb, tag);
316 } else {
317 return __vlan_put_tag(skb, tag);
322 * __vlan_get_tag - get the VLAN ID that is part of the payload
323 * @skb: skbuff to query
324 * @tag: buffer to store vlaue
326 * Returns error if the skb is not of VLAN type
328 static inline int __vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
330 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
332 if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
333 return -EINVAL;
336 *tag = ntohs(veth->h_vlan_TCI);
338 return 0;
342 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
343 * @skb: skbuff to query
344 * @tag: buffer to store vlaue
346 * Returns error if @skb->cb[] is not set correctly
348 static inline int __vlan_hwaccel_get_tag(struct sk_buff *skb, unsigned short *tag)
350 struct vlan_skb_tx_cookie *cookie;
352 cookie = VLAN_TX_SKB_CB(skb);
353 if (cookie->magic == VLAN_TX_COOKIE_MAGIC) {
354 *tag = cookie->vlan_tag;
355 return 0;
356 } else {
357 *tag = 0;
358 return -EINVAL;
362 #define HAVE_VLAN_GET_TAG
365 * vlan_get_tag - get the VLAN ID from the skb
366 * @skb: skbuff to query
367 * @tag: buffer to store vlaue
369 * Returns error if the skb is not VLAN tagged
371 static inline int vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
373 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
374 return __vlan_hwaccel_get_tag(skb, tag);
375 } else {
376 return __vlan_get_tag(skb, tag);
380 #endif /* __KERNEL__ */
382 /* VLAN IOCTLs are found in sockios.h */
384 /* Passed in vlan_ioctl_args structure to determine behaviour. */
385 enum vlan_ioctl_cmds {
386 ADD_VLAN_CMD,
387 DEL_VLAN_CMD,
388 SET_VLAN_INGRESS_PRIORITY_CMD,
389 SET_VLAN_EGRESS_PRIORITY_CMD,
390 GET_VLAN_INGRESS_PRIORITY_CMD,
391 GET_VLAN_EGRESS_PRIORITY_CMD,
392 SET_VLAN_NAME_TYPE_CMD,
393 SET_VLAN_FLAG_CMD,
394 GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
395 GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
398 enum vlan_name_types {
399 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */
400 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */
401 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */
402 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */
403 VLAN_NAME_TYPE_HIGHEST
406 struct vlan_ioctl_args {
407 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
408 char device1[24];
410 union {
411 char device2[24];
412 int VID;
413 unsigned int skb_priority;
414 unsigned int name_type;
415 unsigned int bind_type;
416 unsigned int flag; /* Matches vlan_dev_info flags */
417 } u;
419 short vlan_qos;
422 #endif /* !(_LINUX_IF_VLAN_H_) */