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Date:   Thu, 15 Jun 2023 07:58:31 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc:     Hannes Reinecke <hare@suse.de>, linux-fsdevel@vger.kernel.org,
        linux-block@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Hellwig <hch@lst.de>,
        Luis Chamberlain <mcgrof@kernel.org>
Subject: Re: [PATCH 1/2] highmem: Add memcpy_to_folio()
Message-ID: <20230615055831.GA5609@lst.de>
References: <20230614114637.89759-1-hare@suse.de> <20230614134853.1521439-1-willy@infradead.org>
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On Wed, Jun 14, 2023 at 02:48:52PM +0100, Matthew Wilcox (Oracle) wrote:
> This is the folio equivalent of memcpy_to_page(), but it handles large
> highmem folios.  It may be a little too big to inline on systems that
> have CONFIG_HIGHMEM enabled but on systems we actually care about almost
> all the code will be eliminated.

I suspect the right thing is to have the trivial version without kmapping
for !HIGHMEM inline, and a separate version with the kmap loop out of
line for HIGHMEM builds.

Same for the next patch.