release/src/linux/linux/net/atm/ipcommon.c

   1 /* net/atm/ipcommon.c - Common items for all ways of doing IP over ATM */
   2
   3 /* Written 1996-2000 by Werner Almesberger, EPFL LRC/ICA */
   4
   5
   6 #include <linux/module.h>
   7 #include <linux/string.h>
   8 #include <linux/skbuff.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/in.h>
  11 #include <linux/atmdev.h>
  12 #include <linux/atmclip.h>
  13
  14 #include "common.h"
  15 #include "ipcommon.h"
  16
  17
  18 #if 0
  19 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  20 #else
  21 #define DPRINTK(format,args...)
  22 #endif
  23
  24
  25 const unsigned char llc_oui[] = {
  26         0xaa,   /* DSAP: non-ISO */
  27         0xaa,   /* SSAP: non-ISO */
  28         0x03,   /* Ctrl: Unnumbered Information Command PDU */
  29         0x00,   /* OUI: EtherType */
  30         0x00,
  31         0x00 };
  32
  33
  34 /*
  35  * skb_migrate appends the list at "from" to "to", emptying "from" in the
  36  * process. skb_migrate is atomic with respect to all other skb operations on
  37  * "from" and "to". Note that it locks both lists at the same time, so beware
  38  * of potential deadlocks.
  39  *
  40  * This function should live in skbuff.c or skbuff.h.
  41  */
  42
  43
  44 void skb_migrate(struct sk_buff_head *from,struct sk_buff_head *to)
  45 {
  46         struct sk_buff *skb;
  47         unsigned long flags;
  48         struct sk_buff *skb_from = (struct sk_buff *) from;
  49         struct sk_buff *skb_to = (struct sk_buff *) to;
  50         struct sk_buff *prev;
  51
  52         spin_lock_irqsave(&from->lock,flags);
  53         spin_lock(&to->lock);
  54         prev = from->prev;
  55         from->next->prev = to->prev;
  56         prev->next = skb_to;
  57         to->prev->next = from->next;
  58         to->prev = from->prev;
  59         for (skb = from->next; skb != skb_to; skb = skb->next)
  60                 skb->list = to;
  61         to->qlen += from->qlen;
  62         spin_unlock(&to->lock);
  63         from->prev = skb_from;
  64         from->next = skb_from;
  65         from->qlen = 0;
  66         spin_unlock_irqrestore(&from->lock,flags);
  67 }
  68
  69
  70 EXPORT_SYMBOL(llc_oui);
  71 EXPORT_SYMBOL(skb_migrate);