Date: Mon, 01 Dec 1997 13:26:28 -0800 From: Julian Elischer <julian@whistle.com> To: "Fred L. Templin" <templin@erg.sri.com> Cc: freebsd-hackers@freebsd.org Subject: Re: copyout()/copyin() Message-ID: <34832B83.15FB7483@whistle.com> 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?)
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