[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <682db9af-33bc-639d-8930-7a66c30bc644@kernel.dk>
Date: Thu, 26 Apr 2018 09:11:21 -0600
From: Jens Axboe <axboe@...nel.dk>
To: Christoph Hellwig <hch@....de>
Cc: iommu@...ts.linux-foundation.org, linux-arch@...r.kernel.org,
linux-block@...r.kernel.org, linux-ide@...r.kernel.org,
linux-scsi@...r.kernel.org, netdev@...r.kernel.org,
"David S. Miller" <davem@...emloft.net>,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/5] ide: kill ide_toggle_bounce
On 4/26/18 1:20 AM, Christoph Hellwig wrote:
> On Tue, Apr 24, 2018 at 08:02:56PM -0600, Jens Axboe wrote:
>> On 4/24/18 12:16 PM, Christoph Hellwig wrote:
>>> ide_toggle_bounce did select various strange block bounce limits, including
>>> not bouncing at all as soon as an iommu is present in the system. Given
>>> that the dma_map routines now handle any required bounce buffering except
>>> for ISA DMA, and the ide code already must handle either ISA DMA or highmem
>>> at least for iommu equipped systems we can get rid of the block layer
>>> bounce limit setting entirely.
>>
>> Pretty sure I was the one to add this code, when highmem page IO was
>> enabled about two decades ago...
>>
>> Outside of DMA, the issue was that the PIO code could not handle
>> highmem. That's not the case anymore, so this should be fine.
>
> Yes, that is the rationale. Any chance to you could look over the
> other patches as well? Except for the networking one for which I'd
> really like to see a review from Dave all the users of the interface
> are block related.
You can add my reviewed-by to 1-3, and 5. Looks good to me.
--
Jens Axboe
Powered by blists - more mailing lists