Re: CVS commit: src/sys/dev/ata

["Jonathan A. Kollasch" <jakllsch%kollasch.net@localhost>]

On Wed, Oct 05, 2011 at 10:25:52AM +0200, Manuel Bouyer wrote:
> On Wed, Oct 05, 2011 at 03:40:18AM +0000, Jonathan A. Kollasch wrote:
> > Module Name:        src
> > Committed By:       jakllsch
> > Date:               Wed Oct  5 03:40:18 UTC 2011
> > 
> > Modified Files:
> >     src/sys/dev/ata: wd.c
> > 
> > Log Message:
> > Limit wd(4) transfers to 128 (512-byte) logical sectors, as the traditional
> > MAXPHYS value has for at least the past decade.
> 
> We should be able to go safely up to 256 sectors. Anything larger requires
> LBA48, which is not supported by some controllers.

Do we know how a real ST506 or similar ancient drive would respond
to such a command?  Then again, maybe we shouldn't care until someone
reports it doesn't work.  Currently we limit transfers to 255 sectors.
Presumably we're assuming that the register value of 0 used for 256
might be mishandled.

        Jonathan Kollasch