Date: Tue, 15 Sep 2009 01:33:21 -0700 (PDT)
Message-Id: <20090915.013321.07006714.davem@davemloft.net>
To: yi.zhu@intel.com
Cc: mel@csn.ul.ie, reinette.chatre@intel.com, elendil@planet.nl,
	Larry.Finger@lwfinger.net, linville@tuxdriver.com,
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	linux-wireless@vger.kernel.org,
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	johannes@sipsolutions.net, mohamed.abbas@intel.com,
	netdev@vger.kernel.org
Subject: Re: alloc skb based on a given data buffer
From: David Miller <davem@davemloft.net>
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	<1253003420.7549.51.camel@debian>
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From: Zhu Yi <yi.zhu@intel.com>
Date: Tue, 15 Sep 2009 16:30:20 +0800

> This way, device drivers can allocate the Rx buffers with their own size
> and alignment requirement. i.e. do an order-1 page allocation directly
> with free_pages() in the iwlagn driver for a 256 bytes aligned 8K Rx
> buffer. After DMA is finished, drivers can use the above function to
> assemble an skb based on the Rx buffer. It should resolve the problem
> for requiring an order-2 allocation by alloc_skb() in the first place.

You can create paged RX skbs just like drivers such as niu.c
and others already do, there is no need for special APIs for
this.