Re: [PATCH] ieee1394: sbp2: lower block queue alignment requirement

[Stefan Richter <stefanr@s5r6.in-berlin.de>]

On 14 Jan, James Bottomley wrote:
> The block layer currently provides sector (512) byte alignment
> guarantees.  However, there has been talk in SCSI of reducing that to
> word (4) since that's what most intelligent PCI controllers can cope
> with.  If you have any alignment constraints, they should be expressed
> in the slave configure.

OK, thanks. I will keep the explicit setting of the mask then.
I actually think that everything should work just fine with 4 bytes
alignment, but the SBP-2 spec mentiones 8 bytes alignment for the S/G
tables.  So maybe device firmwares will expect it that way even though
IEEE 1394 doesn't impose such a restriction even on transfers with a
payload of a multiple of 8 bytes.
-- 
Stefan Richter
-=====-=-=== ---= -===-
http://arcgraph.de/sr/


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