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Subject: Re: [RFC PATCH 6/9] iomap: use set/clear_fs_page_private
To:     Matthew Wilcox <willy@infradead.org>
Cc:     linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        hch@infradead.org, david@fromorbit.com,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        linux-xfs@vger.kernel.org
References: <20200426214925.10970-1-guoqing.jiang@cloud.ionos.com>
 <20200426214925.10970-7-guoqing.jiang@cloud.ionos.com>
 <20200427002631.GC29705@bombadil.infradead.org>
From:   Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Message-ID: <9dc98fe6-f65e-55ee-5e3e-94f4bbc0e2c7@cloud.ionos.com>
Date:   Mon, 27 Apr 2020 10:15:49 +0200
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On 4/27/20 2:26 AM, Matthew Wilcox wrote:
> On Sun, Apr 26, 2020 at 11:49:22PM +0200, Guoqing Jiang wrote:
>> @@ -59,24 +59,18 @@ iomap_page_create(struct inode *inode, struct page *page)
>>   	 * migrate_page_move_mapping() assumes that pages with private data have
>>   	 * their count elevated by 1.
>>   	 */
>> -	get_page(page);
>> -	set_page_private(page, (unsigned long)iop);
>> -	SetPagePrivate(page);
>> -	return iop;
>> +	return (struct iomap_page *)set_fs_page_private(page, iop);
>>   }
> This cast is unnecessary.  void * will be automatically cast to the
> appropriate pointer type.
>
>> @@ -556,11 +550,9 @@ iomap_migrate_page(struct address_space *mapping, struct page *newpage,
>>   
>>   	if (page_has_private(page)) {
>>   		ClearPagePrivate(page);
>> -		get_page(newpage);
>> -		set_page_private(newpage, page_private(page));
>> +		set_fs_page_private(newpage, (void *)page_private(page));
>>   		set_page_private(page, 0);
>>   		put_page(page);
>> -		SetPagePrivate(newpage);
>>   	}
> Same comment here as for the btrfs migrate page that Dave reviewed.

Yes, thanks for the review.

Thanks,
Guoqing