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Date:   Thu, 20 Jul 2023 06:54:59 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     io-uring@vger.kernel.org, linux-xfs@vger.kernel.org, hch@lst.de,
        andres@anarazel.de, david@fromorbit.com
Subject: Re: [PATCH 3/6] iomap: treat a write through cache the same as FUA
Message-ID: <20230720045459.GC1811@lst.de>
References: <20230719195417.1704513-1-axboe@kernel.dk> <20230719195417.1704513-4-axboe@kernel.dk>
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On Wed, Jul 19, 2023 at 01:54:14PM -0600, Jens Axboe wrote:
> Whether we have a write back cache and are using FUA or don't have
> a write back cache at all is the same situation. Treat them the same.

This looks correct, but I think the IOMAP_DIO_WRITE_FUA is rather
misnamed now which could lead to confusion.  The comment in
__iomap_dio_rw when checking the flag and clearing IOMAP_DIO_NEED_SYNC
also needs a little update to talk about writethrough semantics and
not just FUA now.