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Date: Wed, 9 Apr 2025 12:52:29 +0200
From: Christoph Hellwig <hch@lst.de>
To: Roman Kisel <romank@linux.microsoft.com>
Cc: aleksander.lobakin@intel.com, andriy.shevchenko@linux.intel.com,
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Subject: Re: [PATCH hyperv-next 5/6] arch, drivers: Add device struct
 bitfield to not bounce-buffer
Message-ID: <20250409105229.GA5721@lst.de>
References: <20250409000835.285105-1-romank@linux.microsoft.com> <20250409000835.285105-6-romank@linux.microsoft.com>
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In-Reply-To: <20250409000835.285105-6-romank@linux.microsoft.com>
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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.