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Date: Fri, 30 Jan 1998 04:00:36 +1100
From: Bruce Evans <bde@zeta.org.au>
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To: bde@zeta.org.au, toor@dyson.iquest.net
Subject: Re: cvs commit: src/sys/i386/isa wfd.c
Cc: cvs-all@FreeBSD.ORG, cvs-committers@FreeBSD.ORG, cvs-sys@FreeBSD.ORG,
        mike@smith.net.au
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>I don't know if the discussions between Justin and I were public or private,
>but I have admitted that the addition of d_maxio as a single scalar was
>inadequate.  If the driver writers start using it, I'll be glad to do the
>port to change things to a function interface when time has come.  The thing
>that is stopping me from doing it correctly right now is a severe time
>constraint.  If someone wants to do the d_maxio correctly right now, I
>say go for it!!! :-).  The changes aren't complex or substantial, but will
>require more thought than I have put into it.

I didn't see the discussion.

I think a function call bdevswp->d_maxio() would be efficient enough.
You copy the value the vnode on open and always access it from there.
At least if the vnode remains bloated with v_maxio.

There should also be a cdevsw function to give the "best" i/o size.

Bruce