svn commit: r196777 - head/sys/dev/ahci

[Scott Long]

On Sep 5, 2009, at 12:16 AM, Alexander Motin wrote:
> John Baldwin wrote:
>> On Thursday 03 September 2009 3:45:07 pm Ivan Voras wrote:
>>> But ciss doesn't reference it at all so either it deviously  
>>> assumes it
>>> or is independent of it.
>>
>> Actually, it may be much worse, it may be that the author of ciss 
>> (4) new that
>> ciss(4)'s largest supported I/O size was larger than 128k so they  
>> didn't
>> bother handling the limit at all giving the false impression the  
>> hardware has
>> no limit.
>
> In cases of ATA and CAM infrastructures it was is so, that if driver
> does not sets max_iosize or maxio respectively, it uses DFLTPHYS. So
> problem is only about non-ATA/CAM RAIDs or cases where wrong value  
> could
> be specified explicitly.
>
> ciss(4) driver was explicitly limited to 64K, until somebody could
> review it's capabilities.
>

Right, but I don't want people blindly changing this in any of the CAM  
drivers without understanding what is going on.  Also, there are  
plenty of non-CAM block drivers that haven't been audited very well  
yet, if at all.

Scott