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    Subjectsk_buff destructor in 2.2.18
    Hi all,

    I'm trying to figure out how to use the destructor function in the skbuff
    object.
    I've read (the source code and) the alan cox's article from linuxjournal
    but it refers to linux 2.0.
    Perhaps someone can tell me what's wrong in the following :

    Normally the rx code of a network driver do the following code :
    allocate a skbuff
    skb=dev_alloc_skb(length);
    if (skb==NULL) ...
    fill data
    skb_put(skb,length);
    memcpy((void *)skb->data, buf,length);
    end so on ...

    In my case, I own the incomming buffer so I would like to use it directly
    without copying data.
    I've written a new allocation function.
    And use the destructor to free my buffer (replacing it on a free list).

    First I imagine something is wrong because the destructor is called before
    kfree_skbmem() so If I don't lie to skb->cloned (I set it to 1), an
    unexpected skb->head occured.
    I think the destructor method is provided to free privates data not the
    main data. But I can't see an another way to do it.

    Secondly, When my destructor function is called, the cloned flag is already
    set (and datarefp indicates also that data is referenced elsewhere).
    When is a skbuff cloned?
    Is there a way to avoid this?
    Where can I register a function to free (= replace it in my list) the data
    buffer?

    Thank you,
    Christophe

    --
    Christophe Barbé
    Software Engineer - christophe.barbe@lineo.fr
    Lineo France - Lineo High Availability Group
    42-46, rue Médéric - 92110 Clichy - France
    phone (33).1.41.40.02.12 - fax (33).1.41.40.02.01
    http://www.lineo.com

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