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Date:   Fri, 9 Sep 2022 18:46:47 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Cheng Li <lic121@chinatelecom.cn>
Cc:     mike.kravetz@oracle.com, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] mm: use nth_page instead of mem_map_offset
 mem_map_next
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On Fri, Sep 09, 2022 at 07:31:09AM +0000, Cheng Li wrote:
> To handle discontiguity case, mem_map_next() has a parameter named
> `offset`. As a function caller, one would be confused why "get
> next entry" needs a parameter named "offset". The other drawback of
> mem_map_next() is that the callers must take care of the map between
> parameter "iter" and "offset", otherwise we may get an hole or
> duplication during iteration. So we use nth_page instead of
> mem_map_next.
> 
> And replace mem_map_offset with nth_page() per Matthew's comments.
> 
> Signed-off-by: Cheng Li <lic121@chinatelecom.cn>
> Fixes: 69d177c2fc70 ("hugetlbfs: handle pages higher order than MAX_ORDER")

Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>