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-rw-r--r--net/atm/ipcommon.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/net/atm/ipcommon.c b/net/atm/ipcommon.c
new file mode 100644
index 000000000000..181a3002d8ad
--- /dev/null
+++ b/net/atm/ipcommon.c
@@ -0,0 +1,61 @@
+/* net/atm/ipcommon.c - Common items for all ways of doing IP over ATM */
+
+/* Written 1996-2000 by Werner Almesberger, EPFL LRC/ICA */
+
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/in.h>
+#include <linux/atmdev.h>
+#include <linux/atmclip.h>
+
+#include "common.h"
+#include "ipcommon.h"
+
+
+#if 0
+#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
+#else
+#define DPRINTK(format,args...)
+#endif
+
+
+/*
+ * skb_migrate appends the list at "from" to "to", emptying "from" in the
+ * process. skb_migrate is atomic with respect to all other skb operations on
+ * "from" and "to". Note that it locks both lists at the same time, so beware
+ * of potential deadlocks.
+ *
+ * This function should live in skbuff.c or skbuff.h.
+ */
+
+
+void skb_migrate(struct sk_buff_head *from,struct sk_buff_head *to)
+{
+ struct sk_buff *skb;
+ unsigned long flags;
+ struct sk_buff *skb_from = (struct sk_buff *) from;
+ struct sk_buff *skb_to = (struct sk_buff *) to;
+ struct sk_buff *prev;
+
+ spin_lock_irqsave(&from->lock,flags);
+ spin_lock(&to->lock);
+ prev = from->prev;
+ from->next->prev = to->prev;
+ prev->next = skb_to;
+ to->prev->next = from->next;
+ to->prev = from->prev;
+ for (skb = from->next; skb != skb_to; skb = skb->next)
+ skb->list = to;
+ to->qlen += from->qlen;
+ spin_unlock(&to->lock);
+ from->prev = skb_from;
+ from->next = skb_from;
+ from->qlen = 0;
+ spin_unlock_irqrestore(&from->lock,flags);
+}
+
+
+EXPORT_SYMBOL(skb_migrate);