Re: [PATCH 2/4] libata: Implement disk shock protection support

[Tejun Heo <htejun@gmail.com>]

Elias Oltmanns wrote:
> We mustn't release the lock between pulling the actions into eh_context
> and clearing eh_info, so I've designed ata_eh_pull_action() to be used
> instead of ata_eh_about_to_do().

Yes, right again.  :-)

> What about the following patch? Also, I've slipped in a minor comment
> fix to ata_eh_done() which probably doesn't warrant a separate patch; on
> the other hand, mixing things like that isn't quite the right thing
> either, so, perhaps I should drop it in the final version?

Hmmm... I think either way is okay but there's no harm in splitting
them.

> From: Elias Oltmanns <eo@nebensachen.de>
> Subject: [PATCH] libata: Implement disk shock protection support
> 
> On user request (through sysfs), the IDLE IMMEDIATE command with UNLOAD
> FEATURE as specified in ATA-7 is issued to the device and processing of
> the request queue is stopped thereafter until the specified timeout
> expires or user space asks to resume normal operation. This is supposed
> to prevent the heads of a hard drive from accidentally crashing onto the
> platter when a heavy shock is anticipated (like a falling laptop
> expected to hit the floor). In fact, the whole port stops processing
> commands until the timeout has expired in order to avoid any resets due
> to failed commands on another device.
> 
> Signed-off-by: Elias Oltmanns <eo@nebensachen.de>

Acked-by: Tejun Heo <tj@kernel.org>

-- 
tejun