[RFC] change in /proc/devices

[Alexander Viro]

On Thu, 27 Jan 2000, david parsons wrote:

> > Argh... I'ld _really_ like to get rid of major/minor stuff wherever
> > possible. Besides, says who that we will not get a driver for terabyte
> > hardware raid where one can expect more than 256 partitions?
> 
>      Nothing.  That's the advantage of separating out the major and
>      minor numbers -- if you explicitly list the major and minor
>      numbers, userland apps don't have to know how wide a major is
>      to do something with it.

Erm... Flat address space is Good Thing(tm). Very small part of userland
needs to know about the major size.

>      0300[40] means that I have to know that a major is the first 8 bits.

No, you don't. mknod(2) takes dev_t as an argument. Just feed the thing
as is and don't bother with the splitting it up. stat(2) also returns
plain dev_t, so...

> > In lkm you will be able to do much better - another question being what
> > would you do with the results...
> 
>         Need you ask?  If I wrote a lkm, I'd have it export this
>         information as a filesystem so I could mount it on /dev like G-d
>         himself intended, and then I could maybe wedge a 2.4 kernel
> 	onto a Mastodon boot floppy [*].

Urgh... Then you will be better off patching register_disk().

> 	david parsons \bi/ [* Anybody know of a good way to trim 300k from a
>                        \/                                       2.3.x zImage? ]

I don't promise 300k - core of each driver will remain as-is, but glue is
going to shrink. As soon as I'll sort the IDE stuff out[1] I'll submit the
next patch to Linus. And it looks like it will be the last one _adding_
code - from there on it's a big butchery.

BTW, I suspect that you might win quite a few blocks if you will modify
insmod and teach it to load gziped modules. Or just use cramfs...

[1] bloody thing works, but I'ld like to know what (if anything) stops it
from breaking apart...



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo en vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/