Re: [RFC 0/2] libata: support SATA devices on SAS HBAs

[Brian King <brking@us.ibm.com>]

Jeff Garzik wrote:
> Bartlomiej Zolnierkiewicz wrote:
> 
>>[PATCH] libata: add ops->qc_transport for SAS
>>
>>* add ->qc_transport to struct ata_port_operations
>>* add default ata_qc_transport() and update all host drivers
>>
>>Thanks to this change we won't have to depend on host_set
>>and host_set->lock for devices attached to SAS HBAs.
>>
>>Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> 
> 
> 
> Seems sane at a quick glance, though I'm a bit disappointed we have to 
> add yet another level of indirection to the hot path.
> 
> You made a good point, though, by pointing out that all the ata_qc_xxx 
> stuff is essentially completely inside a single lock domain.
> 
> Other notes:  There may be other dependencies such as wanting to 
> reference the struct device pointer in host_set and similar details that 
> need handling.  Also, I was planning to move some of the ata_port_ops 
> into a separate host_set ops, since they (hooks such as ->irq_clear or 
> ->host_stop) are really host-wide hooks, not per-port hooks.

Jeff,

Is this patch on its way into one of your trees, or should I just pick
it up add it to my libata SAS patchset so you can just grab the whole
patchset once it is ready?

Brian

-- 
Brian King
eServer Storage I/O
IBM Linux Technology Center