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From:   Andreas Hindborg <nmi@metaspace.dk>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
        Keith Busch <kbusch@kernel.org>,
        Damien Le Moal <Damien.LeMoal@wdc.com>,
        Hannes Reinecke <hare@suse.de>,
        lsf-pc@lists.linux-foundation.org, rust-for-linux@vger.kernel.org,
        linux-block@vger.kernel.org, Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?utf-8?Q?Bj=C3=B6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
        Benno Lossin <benno.lossin@proton.me>,
        open list <linux-kernel@vger.kernel.org>, gost.dev@samsung.com
Subject: Re: [RFC PATCH 02/11] rust: add `pages` module for handling page
 allocation
Date:   Fri, 05 May 2023 06:42:02 +0200
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Matthew Wilcox <willy@infradead.org> writes:

> On Wed, May 03, 2023 at 11:06:59AM +0200, Andreas Hindborg wrote:
>> From: Andreas Hindborg <a.hindborg@samsung.com>
>> 
>> This patch adds support for working with pages of order 0. Support for pages
>> with higher order is deferred. Page allocation flags are fixed in this patch.
>> Future work might allow the user to specify allocation flags.
>> 
>> This patch is a heavily modified version of code available in the rust tree [1],
>> primarily adding support for multiple page mapping strategies.
>
> This also seems misaligned with the direction of Linux development.
> Folios are the future, pages are legacy.  Please, ask about what's
> going on before wasting time on the past.

I see, thanks for the heads up! In this case I wanted to do an
apples-apples comparison to the C null_blk driver. Since that is using
kmap I wanted to have that. But let's bind to the folio_* APIs in the
future, that would make sense.

Best regards
Andreas