Hi list,

If we map device memory into user space using mmap(), the user will be
able to do read / write into device using normal memory handling
routines, right?

But as mentioned in LDD3, should appropriate readb() / writeb()
routines be actually used to read / write into device memory?

Thanks,

Dan
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On Wed, Mar 28, 2007 at 09:45:52AM +0530, Daniel Rodrick wrote:
> If we map device memory into user space using mmap(), the user will be
> able to do read / write into device using normal memory handling
> routines, right?

Right.

> But as mentioned in LDD3, should appropriate readb() / writeb()
> routines be actually used to read / write into device memory?

LDD3 is right (as usual :).


Erik

- --
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On 3/28/07, Erik Mouw <mouw [at] nl.linux.org> wrote:
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> On Wed, Mar 28, 2007 at 09:45:52AM +0530, Daniel Rodrick wrote:
> > If we map device memory into user space using mmap(), the user will be
> > able to do read / write into device using normal memory handling
> > routines, right?
>
> Right.
>
> > But as mentioned in LDD3, should appropriate readb() / writeb()
> > routines be actually used to read / write into device memory?
>
> LDD3 is right (as usual :).
>

So using mmap() to map device memory into user space, and then reading
/ writing to device memory in same way as normal memory isn't correct?

Thanks,

Dan.
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