Subject: Re: The demise of DEV_BSIZE
To: Jason Thorpe <>
From: Bill Studenmund <>
List: tech-kern
Date: 10/11/1999 17:14:34
On Mon, 11 Oct 1999, Jason Thorpe wrote:

> There *IS* an ioctl for it already!
> DIOCGDEFLABEL returns the "default label" for a device.  This, on disks
> that are capable (i.e. all SCSI and IDE disks) returns the *hardware*
> parameters for the disk, including the sector size, number of sectors,
> and the "geometry".
> It does not read the disklabel from the disklabel area.
> In short, there's already an interface for this, and there is no need
> to add an additional interface to return what is essentially redundant
> information.

I guess you didn't see the rest of the message? NO ioctl is ok, be it
DIOCGDEFLABEL or anything else.

To use an ioctl means changing the semantics of the ioctl call in that it
would be called on unopened devices when currently it is called only on
opened devices. That would mean that all sorts of drivers would be
impacted by getting rid of DEV_BSIZE.

It seems extremely bogus to me for our tty and USB drivers to be impacted
because DEV_BSIZE went away. :-) 

Take care,