Re: [PATCH] SCSI: export sas_hash_addr()

Jeff Garzik
2007-09-30T17:44:44Z

James Bottomley wrote:
> On Thu, 2007-09-27 at 21:01 -0400, Jeff Garzik wrote:
>> James Bottomley wrote:
>>> On Wed, 2007-09-26 at 03:35 -0400, Jeff Garzik wrote:
>>>> sas_hash_addr() is the spec-defined standard hashing function. Make it
>>>> available to drivers that need it.
>>> I'm not opposed in principle to exporting this, but I have a hard time
>>> understanding why a driver would need it.
>>>
>>> The hashed address is a property of the constructed SAS frames, which is
>>> done in libsas. The driver shouldn't really be calculating its own hash
>>> instead of using what libsas provides ... or is this because the hashed
>>> self address isn't calculated by the HBA so it needs to be programmed or
>>> something?
>> It is needed to build the SSP frame header.
>>
>> If there is common code that does that, I will definitely use that, but
>> do not see any such code.
>
> The way you're supposed to build the frame header is in
> lldd_execute_task(). Here, if you need the hashed address of the
> destination, you copy it out of the domain_device (dev field of struct
> sas_task).

That's the destination. I need it for the source.

Jeff