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Date:   Thu, 9 Jun 2022 18:33:23 +0200
From:   David Sterba <dsterba@suse.cz>
To:     "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc:     linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-block@vger.kernel.org, linux-aio@kvack.org,
        linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com,
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        ocfs2-devel@oss.oracle.com, linux-mtd@lists.infradead.org,
        virtualization@lists.linux-foundation.org,
        Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH v2 12/19] btrfs: Convert btrfs_migratepage to
 migrate_folio
Message-ID: <20220609163323.GV20633@twin.jikos.cz>
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        Christoph Hellwig <hch@lst.de>
References: <20220608150249.3033815-1-willy@infradead.org>
 <20220608150249.3033815-13-willy@infradead.org>
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On Wed, Jun 08, 2022 at 04:02:42PM +0100, Matthew Wilcox (Oracle) wrote:
> Use filemap_migrate_folio() to do the bulk of the work, and then copy
> the ordered flag across if needed.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> Reviewed-by: Christoph Hellwig <hch@lst.de>

Acked-by: David Sterba <dsterba@suse.com>

> +static int btrfs_migrate_folio(struct address_space *mapping,
> +			     struct folio *dst, struct folio *src,
>  			     enum migrate_mode mode)
>  {
> -	int ret;
> +	int ret = filemap_migrate_folio(mapping, dst, src, mode);
>  
> -	ret = migrate_page_move_mapping(mapping, newpage, page, 0);
>  	if (ret != MIGRATEPAGE_SUCCESS)
>  		return ret;
>  
> -	if (page_has_private(page))
> -		attach_page_private(newpage, detach_page_private(page));

If I'm reading it correctly, the private pointer does not need to be set
like that anymore because it's done somewhere during the
filemap_migrate_folio() call.

> -
> -	if (PageOrdered(page)) {
> -		ClearPageOrdered(page);
> -		SetPageOrdered(newpage);
> +	if (folio_test_ordered(src)) {
> +		folio_clear_ordered(src);
> +		folio_set_ordered(dst);
>  	}