Re: [RFD w/info-PATCH] device arguments from lookup, partion code

Ingo Oeser
2001-05-22T00:22:55Z

On Mon, May 21, 2001 at 05:51:08PM -0400, Alexander Viro wrote:
> Sure. But we have to do two syscalls only if ioctl has both in- and out-
> arguments that way. Moreover, we are talking about non-trivial in- arguments.
> How many of these are in hotspots?

ioctl has actually 4 semantics:

command only
command + read
command + write
command + rw-transaction

Separating these would be a first step. And yes, I consider each
of them useful.

command only: reset drive
command + rw-transaction: "dear device please mangle this data"
(crypto processors come to mind...)

The other two are obviously needed and already accepted by all of
you.

Hotspots: crypto hardware or generally DSPs.

Regards

Ingo Oeser
--
To the systems programmer,
users and applications serve only to provide a test load.