Re: [PATCH 2/5] ide: kill ide_toggle_bounce

From: Jens Axboe
Date: Thu Apr 26 2018 - 11:11:44 EST


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