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Date: Mon, 01 Dec 1997 13:26:28 -0800
From: Julian Elischer <julian@whistle.com>
Organization: Whistle Communications
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To: "Fred L. Templin" <templin@erg.sri.com>
CC: freebsd-hackers@freebsd.org
Subject: Re: copyout()/copyin()
References: <199712011952.LAA10723@grayling.erg.sri.com>
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Fred L. Templin wrote:
> 
> Hi,
> 
> I'm designing an interface in which I need to move data directly between
> user and kernel buffers using copyout() and copyin(). The interface works
> fine when called synchronously within process context (e.g. the user process
> calls ioctl(), giving the address of a buffer, and the kernel calls copyout()
> or copyin() to move the data). But, what I really want is an *asynchronous*
> interface in which the kernel can move data to/from the user buffers from
> within an interrupt service routine - and it's my understanding that copyout()
> and copyin() aren't suited for this. Am I wrong about this? If not, are there
> alternatives to copyout()/copyin() which can be used to implement such an
> interface?
> 
> Fred
> templin@erg.sri.com

look at how the physio() routine maps in pages from the user's
address space.
(or in fact. USE physio() to do yur work?)