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Date: Fri, 25 Sep 2026 07:54:20 +0200
From: Christoph Hellwig <hch@lst.de>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Carlos Maiolino <cem@kernel.org>,
	Jens Axboe <axboe@kernel.dk>,
	Christian Brauner <brauner@kernel.org>, linux-xfs@vger.kernel.org,
	linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 03/21] xfs: add a xfs_buf_read_async buffer cache API
Message-ID: <20260925055420.GB3193@lst.de>
References: <20260924100032.2733101-1-hch@lst.de> <20260924100032.2733101-4-hch@lst.de> <20260924214341.GE2705364@frogsfrogsfrogs>
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On Thu, Sep 24, 2026 at 02:43:41PM -0700, Darrick J. Wong wrote:
> On Thu, Sep 24, 2026 at 11:59:35AM +0200, Christoph Hellwig wrote:
> > Add a new helper that reads a buffer asynchronously.  This is similar
> > to readahead, but doesn't become a no-op under memory or I/O congestion
> > and returns the buffer to be read.
> > 
> > The intended use is to kick off a read of data checksum buffers at
> > roughly the same time as the data read so that they are available
> > in the I/O completion handler.
> 
> Does there need to be a "wait until this async-read buffer reaches
> XBF_DONE" function too?  Or how do callers do that?

Using the new xfs_buf_read_async_wait function added in this patch.
I'll reword the commit log to make it more clear that it exists and needs
to be used.