Re: unsigned long ioremap()?

[Abramo Bagnara <abramo@alsa-project.org>]

Jeff Garzik wrote:
> 
> Abramo Bagnara wrote:
> > "David S. Miller" wrote:
> > > There is a school of thought which believes that:
> > >
> > > struct xdev_regs {
> > >         u32 reg1;
> > >         u32 reg2;
> > > };
> > >
> > >         val = readl(&regs->reg2);
> > >
> > > is cleaner than:
> > >
> > > #define REG1 0x00
> > > #define REG2 0x04
> > >
> > >         val = readl(regs + REG2);
> 
> > The problem I see is that with the former solution nothing prevents from
> > to do:
> >
> >         regs->reg2 = 13;
> 
> Why should there be something to prevent that?
> 
> If a programmer does that to an ioremapped area, that is a bug.  Pure
> and simple.
> 
> We do not need extra mechanisms simply to guard against programmers
> doing the wrong thing all the time.
>
> > That's indeed the reason to change ioremap prototype for 2.5.
> 
> Say what??
> 

Please give a look
http://www.uwsg.indiana.edu/hypermail/linux/kernel/0008.1/0338.html
http://www.uwsg.indiana.edu/hypermail/linux/kernel/0008.1/0407.html

This was something that already got a wide consent.

-- 
Abramo Bagnara                       mailto:abramo@alsa-project.org

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It sounds good!