Messages in this thread | | | Date | Wed, 13 Oct 2004 12:22:34 +0100 | From | Russell King <> | Subject | Re: Choosing scatter/gather limits |
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On Mon, Oct 11, 2004 at 12:53:23PM +0200, Pierre Ossman wrote: > I've been adding scatter/gather support for the MMC host driver I'm > writing. I cannot find any documentation on how to chose the limits though.
It seems that you have to read the block layer code to find out what's going on with these limits. There's some documentation on it in Documentation/block/bio.txt. If it's lacking, then please send comments to the block layer people to add the necessary information.
Please also note that I'm intending to make the MMC host drivers know nothing about block IO stuff, so all you'll be passed is the MMC commands and a scatter gather list - so making sure that your driver always uses blk_rq_map_sg() and works from the SG list will ensure that your driver remains easy to update.
-- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 PCMCIA - http://pcmcia.arm.linux.org.uk/ 2.6 Serial core - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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