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Message-ID: <ddd3eb76-5595-4946-95c2-067d5fbaae99@redhat.com>
Date:   Wed, 8 Jun 2022 18:55:46 +0200
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Subject: Re: [PATCH v4 3/4] fat: add renameat2 RENAME_EXCHANGE flag support
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To:     OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc:     linux-kernel@vger.kernel.org,
        Lennart Poettering <lennart@poettering.net>,
        Colin Walters <walters@verbum.org>,
        Peter Jones <pjones@redhat.com>,
        Alberto Ruiz <aruiz@redhat.com>,
        Christian Kellner <ckellner@redhat.com>,
        Chung-Chiang Cheng <cccheng@synology.com>,
        Muhammad Usama Anjum <usama.anjum@collabora.com>,
        Alexander Larsson <alexl@redhat.com>
References: <20220601173204.1372569-1-javierm@redhat.com>
 <20220601173204.1372569-4-javierm@redhat.com>
 <87h74vteb1.fsf@mail.parknet.co.jp>
From:   Javier Martinez Canillas <javierm@redhat.com>
In-Reply-To: <87h74vteb1.fsf@mail.parknet.co.jp>
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On 6/8/22 16:33, OGAWA Hirofumi wrote:
> Javier Martinez Canillas <javierm@redhat.com> writes:
> 
>> +	/* update ".." directory entry info */
>> +	if (old_dotdot_de) {
>> +		err = vfat_update_dotdot_de(new_dir, old_inode, old_dotdot_bh,
>> +					    old_dotdot_de);
>> +		if (err)
>> +			goto error_old_dotdot;
>> +		drop_nlink(old_dir);
>> +		inc_nlink(new_dir);
>> +	}
>> +
>> +	if (new_dotdot_de) {
>> +		err = vfat_update_dotdot_de(old_dir, new_inode, new_dotdot_bh,
>> +					    new_dotdot_de);
>> +		if (err)
>> +			goto error_new_dotdot;
>> +		drop_nlink(new_dir);
>> +		inc_nlink(old_dir);
>> +	}
> 
> Probably, we should change the nlink only if both of dotdot update are
> succeed and different file type. Otherwise, we would have to revert the
> nlink change on error path (and can remove unnecessary update as bonus).
> 

Agreed. I'll wait a few days before posting v5 in case you have more
comments on the other patches.

-- 
Best regards,

Javier Martinez Canillas
Linux Engineering
Red Hat