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Date:   Mon, 30 Mar 2020 05:50:06 -0700
From:   Matthew Wilcox <willy@infradead.org>
To:     Wei Yang <richard.weiyang@gmail.com>
Cc:     linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 6/9] XArray: internal node is a xa_node when it is bigger
 than XA_ZERO_ENTRY
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 <20200330123643.17120-7-richard.weiyang@gmail.com>
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On Mon, Mar 30, 2020 at 12:36:40PM +0000, Wei Yang wrote:
> As the comment mentioned, we reserved several ranges of internal node
> for tree maintenance, 0-62, 256, 257. This means a node bigger than
> XA_ZERO_ENTRY is a normal node.
> 
> The checked on XA_ZERO_ENTRY seems to be more meaningful.

257-1023 are also reserved, they just aren't used yet.  XA_ZERO_ENTRY
is not guaranteed to be the largest reserved entry.