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Date:   Sun, 27 Feb 2022 14:13:43 -0800
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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:     Jens Axboe <axboe@kernel.dk>, 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>
References: <20220227093434.2889464-1-jhubbard@nvidia.com>
 <20220227093434.2889464-5-jhubbard@nvidia.com>
 <8b5b35fa-3c70-adc8-ca3a-4829388c4d12@kernel.dk>
From:   John Hubbard <jhubbard@nvidia.com>
In-Reply-To: <8b5b35fa-3c70-adc8-ca3a-4829388c4d12@kernel.dk>
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On 2/27/22 13:59, Jens Axboe wrote:
> 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.
> 

Sorry about that, I'll sit down and write up something thorough for this
patch. It is after the central thing, and it got neglected here.

thanks,
-- 
John Hubbard
NVIDIA