Re: [alliance-iosk] Driver programming and GPL

[vhandel@chem.vu.nl (Ramon van Handel)]

>Yes, the boot code do whatever needed, so it's not the correct interfcace,
>though I expect that in a way or another we don't duplicate drivers (/ABL and
>/LM?IOSK) because it's a waste of resources and we don't have a lot of them.
>But the real question is: which kind of interface I use? Can I use outp,inp, or
>IOPL of  IOSK LMs forbid that? When I need an IRQ what I call? I'll need this
>sooner or later....

Well, right now, all EKs have IO permissions.  But I don't want to keep it
that way.  As soon as CK security is implemented, I will turn this off -
that way, any user can load a new EK, but that EK cannot mess with the
hardware --> stable system.  When that is implemented, an EK that wants
hardware access needs to request I/O permissions from the CK.  It can get
permissions on a specific I/O region (I/O bitmap, IOPL=0.  Also specific
capability needed, perhaps 1/x). You request an I/O region using resources.
The CK determines your capability and according to that either gives you
permissions on I/O, or denies you permissions.  It would deny permissions
to an I/O area that is in use by another EK.

An EK that has the same capability as needed for I/O region allocation can
also request global interrupt forwarding.  In that case, the CK will send a
signal to that thread that requested it every time that interrupt (IRQ)
occurs.

Ramon

---
Ramon van Handel   <vhandel@chem.vu.nl>
Chemistry Student, OS Programmer and all-round Weirdo
The ant has made himself illustrious / Through constant industry industrious.
So what? Would you be calm and placid / If you were full of formic acid?
(Ogden Nash)


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