Subject: Re: Work-in-progress "wedges" implementation
To: Daniel Carosone <>
From: Jason Thorpe <>
List: tech-kern
Date: 09/22/2004 16:35:37
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On Sep 22, 2004, at 3:44 PM, Daniel Carosone wrote:

> Something like we do now. For the "just let me access whatever's in
> the drive, I don't want to have to know/care what particular disk it
> is" case.

Oh.  Well, eventually a whole-disk e.g. /dev/sd0 will be there.  The 
wedges are also named /dev/dk0, /dev/dk1, etc.  The /dev/dk/WegeName 
names are really intended to just be aliases.  If the wedge doesn't 
have a name, you can still access via the /dev/dkN path.

> Many flash usb widgets have an partition table on them, but its very
> rare that there's more than one whole-disk partition defined.

Understood.  Nevertheless, having that partition be named is very 
useful, so that your /etc/fstab entry always works, regardless of probe 
order, e.g.:

/dev/dk/DanFlashKey /frob msdos rw,noauto 0 0

As you said, this can be done using e.g. the MS-DOS volume name.

> Also, of course there'll be a bsd-disklabel wedge loader, and some
> kind of scheme to make compatible naming and migration easy, later.

Yes.  For the BSD disklabel wedge loader, my thought is to name the 
wedges like our existing partitions are named, e.g. "sd0a", "wd0e", 
etc.  So, there would be:


...and then some compatibility shim at the old major numbers that 
somehow "symlink" to the new names.

Or something.

         -- Jason R. Thorpe <>

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