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Date: Thu, 10 Apr 2025 09:21:50 +0200
From: Christoph Hellwig <hch@lst.de>
To: Roman Kisel <romank@linux.microsoft.com>
Cc: Robin Murphy <robin.murphy@arm.com>, aleksander.lobakin@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: <20250410072150.GA32563@lst.de>
References: <20250409000835.285105-1-romank@linux.microsoft.com> <20250409000835.285105-6-romank@linux.microsoft.com> <0eb87302-fae8-4708-aaf8-d16e836e727f@arm.com> <0ab2849a-5c03-4a8c-891e-3cb89b20b0e4@linux.microsoft.com>
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On Wed, Apr 09, 2025 at 09:44:03AM -0700, Roman Kisel wrote:
> Do you feel this is shoehorned in `struct device`? I couldn't find an
> appropriate private (== opaque pointer) part in the structure to store
> that bit (`struct device_private` wouldn't fit the bill) and looked like
> adding it to the struct itself would do no harm. However, my read of the
> room is that folks see that as dubious :)

We'll need per-device information.  But it is much higher level than a
need bounce buffer flag.