Re: Support multiply-LUN devices in ub

[Matthew Dharm <mdharm-kernel@one-eyed-alien.net>]

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On Sun, May 01, 2005 at 09:24:38PM -0700, Pete Zaitcev wrote:
> On Sun, 1 May 2005 21:05:05 -0700, Matthew Dharm <mdharm-kernel@one-eyed-alien.net> wrote:
> > On Sun, May 01, 2005 at 04:05:40PM -0700, Pete Zaitcev wrote:
> 
> > >  /*
> > > + * This many LUNs per USB device.
> > > + * Every one of them takes a host, see UB_MAX_HOSTS.
> > >   */
> > > +#define UB_MAX_LUNS   4
> > 
> > Why only 4 LUNs?
> 
> This can be redefined at any moment, fortunately, so there's no need to
> agonize over this number. There is no backward or forward compatibility
> problem. The sole purpose of that limit is to make a probe loop bound,
> for initial testing.
> 
> Why would you want more though? I have a 12-in-1 reader which only
> exports 4 LUNs. If someone attached enterprise storage arrays to USB,
> it might be a good idea to remove the limit completely.

I've seen 5 and 6 LUNs, but they aren't common.

The best reading of the specs suggest that 8 is the practical limit.

Since that's not far from 4, perhaps it would be best to set the number to
8 so we never have to revisit it again.

Matt

-- 
Matthew Dharm                              Home: mdharm-usb@one-eyed-alien.net 
Maintainer, Linux USB Mass Storage Driver

Hey, has anyone seen the Microsoft sales guy? It's his feeding time...
					-- Mike
User Friendly, 4/17/1998

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