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Date: Thu, 26 Oct 2017 21:17:36 -0700
From: Liu Bo <bo.li.liu@oracle.com>
To: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: linux-btrfs@vger.kernel.org
Subject: Re: What is the purpose of EXTENT_PAGE_MAPPED
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On Tue, Oct 24, 2017 at 05:47:11AM -0500, Goldwyn Rodrigues wrote:
> 
> EXTENT_PAGE_MAPPED gets set in set_page_extent_mapped(), but I don't see
> it being cross checked anytime. What is the purpose of setting it?

Please check commit d1310b2e0cd98eb1348553e69b73827b436dca7b, it was
used to differentiate page for metadata and for data, but I think
currently it's just a piece of legacy code.

-liubo