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Date:   Wed, 11 Jan 2023 02:34:47 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Ira Weiny <ira.weiny@intel.com>,
        Dan Carpenter <error27@gmail.com>
Subject: Re: [PATCH v2 2/4] fs/sysv: Change the signature of dir_get_page()
Message-ID: <Y74gRx6jLf2RHgdq@ZenIV>
References: <20230109170639.19757-1-fmdefrancesco@gmail.com>
 <20230109170639.19757-3-fmdefrancesco@gmail.com>
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On Mon, Jan 09, 2023 at 06:06:37PM +0100, Fabio M. De Francesco wrote:
>  
> -struct sysv_dir_entry * sysv_dotdot (struct inode *dir, struct page **p)
> +struct sysv_dir_entry *sysv_dotdot(struct inode *dir, struct page **p)
>  {
> -	struct page *page = dir_get_page(dir, 0);
> -	struct sysv_dir_entry *de = NULL;
> +	struct page *page = NULL;
> +	struct sysv_dir_entry *de = dir_get_page(dir, 0, &page);
>  
> -	if (!IS_ERR(page)) {
> -		de = (struct sysv_dir_entry*) page_address(page) + 1;
> +	if (!IS_ERR(de)) {
>  		*p = page;
> +		return (struct sysv_dir_entry *)page_address(page) + 1;
>  	}
> -	return de;
> +	return NULL;
>  }

Would be better off with 

	struct sysv_dir_entry *de = dir_get_page(dir, 0, p);

	if (!IS_ERR(de))
		return de + 1;	// ".." is the second directory entry
	return NULL;

IMO...