Re: Areca RAID driver remaining items?

["erich" <erich@areca.com.tw>]

Dear Arjan van de Ven,

I would keep dma_alloc_coherent usage.

> [Exception is that you can say that you are ok with a bigger mask for
> this type of memory, but just don't do that if you're not]

Should I remove "pci_set_dma_mask(pci_device, DMA_64BIT_MASK)" for this 
case?

Best Regards
Erich Chen

----- Original Message ----- 
From: "Arjan van de Ven" <arjan@infradead.org>
To: "erich" <erich@areca.com.tw>
Cc: """Christoph Hellwig""" <hch@infradead.org>; 
<linux-scsi@vger.kernel.org>; <linux-kernel@vger.kernel.org>; 
<billion.wu@areca.com.tw>; <alan@lxorguk.ukuu.org.uk>; <akpm@osdl.org>; 
<oliver@neukum.org>
Sent: Thursday, February 23, 2006 8:07 PM
Subject: Re: Areca RAID driver remaining items?


> On Thu, 2006-02-23 at 19:51 +0800, erich wrote:
>> If Linux can not assurent the contingous memory space allocating of
>> "dma_alloc_coherent" .
>
> coherent memory is guaranteed to be in the "lower" 32 bit of memory!
> So that is good news, I think you are just fine.
>
> [Exception is that you can say that you are ok with a bigger mask for
> this type of memory, but just don't do that if you're not]
>
>
>> When arcmsr get a physical ccb address from areca's firmware.
>> Does linux has any functions for converting of  "bus to virtual" ?
>
> not without using pools. You would have to search the list of memory you
> gave it to find that out.
>
> (USB has a similar problem, afaik they solved it with pools)
>
>