From: Tejun Heo <htejun@gmail.com>
To: James Bottomley <James.Bottomley@HansenPartnership.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>
Subject: Re: ata_ram driver
Date: Fri, 07 Mar 2008 09:28:34 +0900 [thread overview]
Message-ID: <47D08C32.8060907@gmail.com> (raw)
In-Reply-To: <1204849353.3062.107.camel@localhost.localdomain>
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.
Thanks.
--
tejun
next prev parent reply other threads:[~2008-03-07 0:28 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-02-22 20:09 ata_ram driver Matthew Wilcox
2008-02-22 21:27 ` Mark Lord
2008-03-06 8:21 ` Tejun Heo
2008-03-06 15:28 ` James Bottomley
2008-03-06 23:55 ` Tejun Heo
2008-03-07 0:01 ` James Bottomley
2008-03-07 0:13 ` Tejun Heo
2008-03-07 0:22 ` James Bottomley
2008-03-07 0:28 ` Tejun Heo [this message]
2008-03-07 0:39 ` James Bottomley
2008-03-07 0:43 ` Tejun Heo
2008-03-07 3:08 ` [PATCH 1/2] scsi: export scsi_forget_host() Tejun Heo
2008-03-07 3:11 ` [PATCH 2/2] libata: kill SCSI devices before detaching ata_host Tejun Heo
2008-03-07 2:16 ` ata_ram driver Jeff Garzik
2008-03-07 2:44 ` James Bottomley
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