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	Fri, 08 Nov 2024 18:46:49 +0000
Date: Fri, 8 Nov 2024 18:46:49 +0000
From: Matthew Wilcox <willy@infradead.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, hannes@cmpxchg.org,
	clm@meta.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 11/13] iomap: make buffered writes work with RWF_UNCACHED
Message-ID: <Zy5cmQyCE8AgjPbQ@casper.infradead.org>
References: <20241108174505.1214230-1-axboe@kernel.dk>
 <20241108174505.1214230-12-axboe@kernel.dk>
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In-Reply-To: <20241108174505.1214230-12-axboe@kernel.dk>

On Fri, Nov 08, 2024 at 10:43:34AM -0700, Jens Axboe wrote:
> +++ b/fs/iomap/buffered-io.c
> @@ -959,6 +959,8 @@ static loff_t iomap_write_iter(struct iomap_iter *iter, struct iov_iter *i)
>  		}
>  		if (iter->iomap.flags & IOMAP_F_STALE)
>  			break;
> +		if (iter->flags & IOMAP_UNCACHED)
> +			folio_set_uncached(folio);

This seems like it'd convert an existing page cache folio into being
uncached?  Is this just leftover from a previous version or is that a
design decision you made?