Re: IDE from current bk tree, UDMA and two channels...

["Petr Vandrovec" <VANDROVE@vc.cvut.cz>]

On  1 Aug 02 at 18:39, Alexander Viro wrote:
> On Fri, 2 Aug 2002, Marcin Dalecki wrote:
> 
> > > I'd like to apologize to Ingo, his changes were completely innocent.
> > > Problem was triggered by Al's 'block device size cleanups' (currently
> > > cset 1.403.160.5 on bkbits).
> > > 
> > > Before this change, my system was using 4KB block size when reading
> > > from /dev/hdc1, because of blk_size[][] (which is in 1kB units) of this 
> > > partition was multiple of 2, and so i_size % 4096 was 0.  But after
> > > Al's change partition size is read from gendisk, and not from blk_size,
> > > and gendisk partition size is in 512 bytes units: and, as you can
> > > probably guess, now my partition had i_size % 4096 == 512, and so only
> > > 512 byte block size was choosen. And with 512 bytes block size my
> > > harddisk refuses to cooperate.
> 
> Uh-oh...
> 
> Let me see if I got it straight:
> 
> a) your disk doesn't work with half-Kb requests
> b) you have a partition with odd number of sectors
> c) hardsect_size is set to half-Kb
> d) old code worked since it rounded size to multiple of kilobyte.
> 
> Correct?

Yes, exactly. Replacing disk is not an option...
                                            Petr Vandrovec