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static DEFINE_SPINLOCK(ptype_lock); 

struct list_head ptype_base[PTYPE_HASH_SIZE] ; 
struct list_head ptype_all ; /* Taps */

struct packet_type {
__be16  type; /* This is really htons(ether_type). */
struct net_device *dev; /* NULL is wildcarded here     */
int (*func) (struct sk_buff *,
struct net_device *,
struct packet_type *,
struct net_device *);
bool (*id_match)(struct packet_type *ptype,
   struct sock *sk);
void *af_packet_priv;
struct list_head list;
 };
void dev_add_pack(struct packet_type *pt)
 {
struct list_head *head = ptype_head(pt);


spin_lock(&ptype_lock);
list_add_rcu(&pt->list, head);
spin_unlock(&ptype_lock);
 }
 EXPORT_SYMBOL(dev_add_pack);
void __dev_remove_pack(struct packet_type *pt)
 {
struct list_head *head = ptype_head(pt);
struct packet_type *pt1;


spin_lock(&ptype_lock);


list_for_each_entry(pt1, head, list) {
if (pt == pt1) {
list_del_rcu(&pt->list);
goto out;
}
}


pr_warn("dev_remove_pack: %p not found\n", pt);
 out:
spin_unlock(&ptype_lock);
 }
 EXPORT_SYMBOL(__dev_remove_pack);
void dev_remove_pack(struct packet_type *pt)
 {
__dev_remove_pack(pt);


synchronize_net();
 }
 EXPORT_SYMBOL(dev_remove_pack);
static struct packet_type ip_packet_type = {
.type = cpu_to_be16(ETH_P_IP),
.func = ip_rcv,
 };static struct packet_type ipv6_packet_type  = {
.type = cpu_to_be16(ETH_P_IPV6),
.func = ipv6_rcv,
 };static struct packet_type can_packet __read_mostly = {
.type = cpu_to_be16(ETH_P_CAN),
.func = can_rcv,
 };


 static struct packet_type canfd_packet __read_mostly = {
.type = cpu_to_be16(ETH_P_CANFD),
.func = canfd_rcv,
 };static struct packet_type rarp_packet_type = {
.type =  cpu_to_be16(ETH_P_RARP),
.func =  ic_rarp_recv,
 };
static struct packet_type llc_packet_type __read_mostly = {
.type = cpu_to_be16(ETH_P_802_2),
.func = llc_rcv,
 };


 static struct packet_type llc_tr_packet_type __read_mostly = {
.type = cpu_to_be16(ETH_P_TR_802_2),
.func = llc_rcv,
 };