Re: linux kernel without file system

Xavier Bestel
2009-01-14T10:21:42Z

On Wed, 2009-01-14 at 10:34 +0100, Philippe De Muyter wrote:
> On Wed, Jan 14, 2009 at 09:46:48AM +0100, Tomasz Chmielewski wrote:
> >> I need to design a very small embedded system that must only control
> >> one ethernet port and two serial lines and must fit in a very small flash
> >> memory. So I thought about replacing the call to /etc/init by my
> >> application
> >> program and removing all the file-system part of linux.
> >> Is that doable ?
> >> Is there a 'standard' way of doing that ?
> >> The first problem I see is accessing my serial lines. How could I do that
> >> without using open("/dev/ttySx"), which requires a file system ?
> >> Is there a way to access devices that does not require a file-system ?
> >
> > You could put everything in initramfs (and embed it in the kernel).
>
> Actually, I was thinking about reducing the footprint of my kernel by
> removing all the fs-related system calls, so the problem is not where
> the file-system is, but how to access (serial) devices without giving their
> "/dev/..." name.

You can still mount sysfs somewhere and access the device nodes from
there.

Xav