Re: [PATCH] Intel Management Engine Interface

From: Marcin Obara
Date: Wed Aug 13 2008 - 03:16:26 EST


2008/8/13 Greg KH <greg@xxxxxxxxx>:
> On Mon, Aug 11, 2008 at 09:23:01PM +0200, Marcin Obara wrote:
>> +/* IOCTL commands */
>> +#define IOCTL_HECI_GET_VERSION \
>> + _IOWR('H' , 0x0, struct heci_message_data)
>
> This can easily be a sysfs file, why not do that instead?
>
sysfs file would require additional file handle used by every userspace client.
GET_VERSION is called frequently, and sysfs file would create extra overhead.
With ioctl - only one file handle is used, and userspace client logic
is simpler.
Normal flow looks like:

open
ioctl(GET_VERSION)
ioctl(CONNECT)
... - do some operations - depends on version
close

or:

open
ioctl(CONNECT)
.. - do some operations
close


--
Marcin
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/