linux-kernel - Re: [PATCH hyperv-next 5/6] arch, drivers: Add device struct bitfield to not bounce-buffer

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Message-ID: <b56eef68-367d-4b7b-98c4-f5d1291d7993@linux.microsoft.com>
Date: Wed, 9 Apr 2025 08:27:22 -0700
From: Roman Kisel <romank@...ux.microsoft.com>
To: Christoph Hellwig <hch@....de>
Cc: aleksander.lobakin@...el.com, andriy.shevchenko@...ux.intel.com,
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Subject: Re: [PATCH hyperv-next 5/6] arch, drivers: Add device struct bitfield
 to not bounce-buffer



On 4/9/2025 3:52 AM, Christoph Hellwig wrote:
> On Tue, Apr 08, 2025 at 05:08:34PM -0700, Roman Kisel wrote:
>> Bounce-buffering makes the system spend more time copying
>> I/O data. When the I/O transaction take place between
>> a confidential and a non-confidential endpoints, there is
>> no other way around.
>>
>> Introduce a device bitfield to indicate that the device
>> doesn't need to perform bounce buffering. The capable
>> device may employ it to save on copying data around.
> 
> I have no idea what this is supposed to mean, you need to explain it
> much better.

Thanks for reviewing! I'll fix the description.

> 

-- 
Thank you,
Roman