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Message-ID: <8b5b35fa-3c70-adc8-ca3a-4829388c4d12@kernel.dk>
Date:   Sun, 27 Feb 2022 14:59:35 -0700
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Subject: Re: [PATCH 4/6] block, bio, fs: convert most filesystems to
 pin_user_pages_fast()
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To:     jhubbard.send.patches@gmail.com, Jan Kara <jack@suse.cz>,
        Christoph Hellwig <hch@infradead.org>,
        Dave Chinner <dchinner@redhat.com>,
        "Darrick J . Wong" <djwong@kernel.org>,
        Theodore Ts'o <tytso@mit.edu>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Miklos Szeredi <miklos@szeredi.hu>,
        Andrew Morton <akpm@linux-foundation.org>,
        Chaitanya Kulkarni <kch@nvidia.com>
Cc:     linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-xfs@vger.kernel.org, linux-mm@kvack.org,
        LKML <linux-kernel@vger.kernel.org>,
        John Hubbard <jhubbard@nvidia.com>
References: <20220227093434.2889464-1-jhubbard@nvidia.com>
 <20220227093434.2889464-5-jhubbard@nvidia.com>
From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <20220227093434.2889464-5-jhubbard@nvidia.com>
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On 2/27/22 2:34 AM, jhubbard.send.patches@gmail.com wrote:
> From: John Hubbard <jhubbard@nvidia.com>
> 
> Use pin_user_pages_fast(), pin_user_page(), and unpin_user_page() calls,
> in place of get_user_pages_fast(), get_page() and put_page().
> 
> This converts the Direct IO parts of most filesystems over to using
> FOLL_PIN (pin_user_page*()) page pinning.

The commit message needs to explain why a change is being made, not what
is being done. The latter I can just look at the code for.

Didn't even find it in in your cover letter, had to go to the original
posting for that.

-- 
Jens Axboe