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Date:   Sun, 26 Mar 2023 17:58:31 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     "Darrick J. Wong" <djwong@kernel.org>,
        Ritesh Harjani <ritesh.list@gmail.com>,
        Theodore Tso <tytso@mit.edu>,
        Andreas Dilger <adilger.kernel@dilger.ca>,
        linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 04/31] ext4: Convert ext4_finish_bio() to use folios
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On Thu, Mar 23, 2023 at 03:30:38PM +0000, Matthew Wilcox wrote:
> I really want to see a cheaper abstraction for accessing the block device
> than BHs.  Or xfs_buf for that matter.

You literally can just use the bdev page cache using the normal page
cache helpers.  It's not quite what most of these file systems expect,
though, especially for the block size < PAGE_SIZE case.