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Date:   Tue, 22 Mar 2022 01:37:37 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Muchun Song <songmuchun@bytedance.com>
Cc:     dan.j.williams@intel.com, willy@infradead.org, jack@suse.cz,
        viro@zeniv.linux.org.uk, akpm@linux-foundation.org,
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        hughd@google.com, xiyuyang19@fudan.edu.cn,
        kirill.shutemov@linux.intel.com, zwisler@kernel.org,
        hch@infradead.org, linux-fsdevel@vger.kernel.org,
        nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, duanxiongchun@bytedance.com, smuchun@gmail.com
Subject: Re: [PATCH v5 5/6] dax: fix missing writeprotect the pte entry
Message-ID: <YjmK0aaCu/FI/t7T@infradead.org>
References: <20220318074529.5261-1-songmuchun@bytedance.com>
 <20220318074529.5261-6-songmuchun@bytedance.com>
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> +static void dax_entry_mkclean(struct address_space *mapping, unsigned long pfn,
> +			      unsigned long npfn, pgoff_t start)
>  {
>  	struct vm_area_struct *vma;
> +	pgoff_t end = start + npfn - 1;
>  
>  	i_mmap_lock_read(mapping);
> +	vma_interval_tree_foreach(vma, &mapping->i_mmap, start, end) {
> +		pfn_mkclean_range(pfn, npfn, start, vma);
>  		cond_resched();
>  	}
>  	i_mmap_unlock_read(mapping);


Is there any point in even keeping this helper vs just open coding it
in the only caller below?

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>