From mboxrd@z Thu Jan  1 00:00:00 1970
From: James Bottomley <James.Bottomley@HansenPartnership.com>
Subject: Re: ata_ram driver
Date: Thu, 06 Mar 2008 18:39:58 -0600
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To: Tejun Heo <htejun@gmail.com>
Cc: Mark Lord <liml@rtr.ca>, Matthew Wilcox <matthew@wil.cx>, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, Jeff Garzik <jeff@garzik.org>

On Fri, 2008-03-07 at 09:28 +0900, Tejun Heo wrote:
> James Bottomley wrote:
> >> Yeap, sure.  It's the combination of things that always made me put this
> >> off.  Is there a function I can call to just shutdown the host instead
> >> of destroying it?
> > 
> > Not really ... the process of unbinding the ULDs causes their remove
> > methods to call shudown.  It is possible to separate this in the ULDS;
> > but the original design was to make remove and shutdown be similar for
> > the very reason that if you're removing the driver with unflushed data
> > in the cache, we'd really like it flushed (flush is called from
> > shutdown) because you have no way to talk to the device after this
> > without reinserting the driver.
> 
> The problem is that libata EH and other stuff aren't ready to let go of
> the SCSI host up until the last moment and that last moment can't be
> moved before SCSI host destruction because shutdown sequence (flush and
> spindown) requires live EH.  I think this can be solved by shooting down
> individual sdev's instead of destroying the scsi_host.

Basically what scsi_scan.c:scsi_forget_host() does?  It's used
internally at the moment, but I suppose we could export it.

James