Clarification regarding design of a device.

[Mulyadi Santosa]

Hi...

On Tue, May 3, 2011 at 00:23, mindentropy <mindentropy at gmail.com> wrote:
> Hi,
>
>   I have say a crypto device and if I pass a data stream assuming echo "test"
>> /dev/aes and when I read it I get an encrypted output. Now if a program
> opens the same device twice should and pass different streams should I
> differentiate those 2 streams and have encrypted buffers of these 2 streams as
> output? If yes how should I differentiate it? Or should I not differentiate and
> provide different devices say aes0,aes1 or should the userspace program worry
> about locking and sharing of resource?

I am not keen regarding char/block device management, but I think you
should separate those streams.

How? Well, same thing like you open a same file twice, right? You're
given two different file descriptor. After all, the "open", "read" and
"write" handler of device IMHO always assume that we wanna achieve
such different stream, right?

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com