Re: a problem about non-linear sk_buff

From: Evgeniy Polyakov (
Date: Wed Oct 10 2001 - 21:08:05 EST

On Tue, 9 Oct 2001 23:51:17 -0400 (EDT)
Jianyong Zhang <> wrote:

JZ> Hi,

JZ> I'm a newcomer of this list. I want to understand the tcp/ip stack's
JZ> implementaion, and hope that I can get your help.

kernlel-net is also good for this kind of questions.

JZ> I find that that sk_buff can be fragmented, and it's called nonlinear.
JZ> What's the meaning of nonlinear? And what are the meaning of

May be because of MTU?

JZ> fields: skb->data_len and skb_shinfo(skb)? I have no idea about them.

As I've right understood it from (excellent Alan's book)
(the best source of documentation fobeginners)
and skbuff.h
skb->data_len is actuall length of the data( that is all packet length -
header length).

skb_shinfo(skb) returns structure that containig number of fragments, list
of it, and some other( what? ).

JZ> May you explain them? Thank you.

I'm trying, but it can be absolutelly wrong :)

JZ> Jianyong Zhang

Evgeniy Polyakov.

WBR. //s0mbre
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

This archive was generated by hypermail 2b29 : Mon Oct 15 2001 - 21:00:37 EST