Subject: Re: nore on disk stats
To: None <>
From: Jason Thorpe <>
List: tech-kern
Date: 11/13/1995 22:32:29
On Tue, 14 Nov 1995 00:30:52 -0500 
 "Perry E. Metzger" <> wrote:

 > Actually, Jason Thorpe has given me a program that walks the kernel
 > tables and gets all of the information very cleanly -- even
 > automatically tells you whats a disk, whats a network interface,
 > etc. I sill need an interface to extract disk geometry information,
 > but given that I'll have about everything I need in order to
 > prrogramatically extract all the information one needs for
 > installation purposes, and in a port independent manner, too! 

Well, like I've mentioned before, this is Really Easy with SCSI.  
However, having an hp300, I do indeed realize that All The World's Not 
SCSI.  What I'd duggest is a new ioctl (DIOCGGEOM maybe?) that would be 
implemented in the individual drivers, like the disklabel-related ones 
are, which fills in a structure like the following:

	struct disk_geom {
		u_int32_t	dg_ncyl;	/* cylinders per unit */
		u_int32_t	dg_ntrk;	/* tracks per cyl */
		u_int32_t	dg_nblk;	/* blocks per unit */
		u_int32_t	dg_blksz;	/* bytes per block */

If you can't get this info from a particular type of hardware, you just 
get back an ENOTTY.

Anyhow, I don't have time to work on anything like that at the moment; 
already have way too much to do :-)  But, this at least might be 
something to think about for 1.2...


Jason R. Thorpe                             
NASA Ames Research Center                               Home: 408.866.1912
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