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Date: Wed, 5 Nov 2025 15:15:04 +0100
From: Christoph Hellwig <hch@lst.de>
To: Keith Busch <kbusch@meta.com>
Cc: linux-block@vger.kernel.org, hch@lst.de, martin.petersen@oracle.com,
	axboe@kernel.dk, Keith Busch <kbusch@kernel.org>
Subject: Re: [RFC PATCH] blk-integrity: support arbitrary buffer alignment
Message-ID: <20251105141504.GC22325@lst.de>
References: <20251104224045.3396384-1-kbusch@meta.com>
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User-Agent: Mutt/1.5.17 (2007-11-01)

I have a hard time understanding how this actually works, mostly due to
"union pi_tuple".  What does that union of two pointers buy us over just
passing a void pointer and deriving the type we need deeper down?  Also
given that taking the address and the comparing it (at thbeginning of
blk_tuple_remap_end) how is this actually going to work?