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Date:   Thu, 21 May 2020 16:30:41 -0700
From:   Matthew Wilcox <willy@infradead.org>
To:     Dave Chinner <david@fromorbit.com>
Cc:     linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        "Kirill A. Shutemov" <kirill@shutemov.name>
Subject: Re: [PATCH v4 10/36] fs: Make page_mkwrite_check_truncate thp-aware
Message-ID: <20200521233041.GG28818@bombadil.infradead.org>
References: <20200515131656.12890-1-willy@infradead.org>
 <20200515131656.12890-11-willy@infradead.org>
 <20200521220139.GS2005@dread.disaster.area>
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On Fri, May 22, 2020 at 08:01:39AM +1000, Dave Chinner wrote:
> On Fri, May 15, 2020 at 06:16:30AM -0700, Matthew Wilcox wrote:
> >  	if (page->mapping != inode->i_mapping)
> >  		return -EFAULT;
> >  
> >  	/* page is wholly inside EOF */
> > -	if (page->index < index)
> > -		return PAGE_SIZE;
> > +	if (page->index + hpage_nr_pages(page) - 1 < index)
> > +		return thp_size(page);
> 
> Can we make these interfaces all use the same namespace prefix?
> Here we have a mix of thp and hpage and I have no clue how hpages
> are different to thps. If they refer to the same thing (i.e. huge
> pages) then can we please make the API consistent before splattering
> it all over the filesystem code?

Yes, they're the same thing.  I'll rename hpage_nr_pages() to thp_count().