From mboxrd@z Thu Jan  1 00:00:00 1970
From: Boaz Harrosh <boaz@plexistor.com>
Subject: Re: Regression caused by using node_to_bdi()
Date: Mon, 13 Apr 2015 15:44:05 +0300
Message-ID: <552BBA15.4040500@plexistor.com>
References: <016d01d07380$fc37fc40$f4a7f4c0$@cn.fujitsu.com> <552A57F8.7020002@plexistor.com> <20150413122110.GE3633@quack.suse.cz>
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Cc: Zhao Lei <zhaolei@cn.fujitsu.com>,
	'Christoph Hellwig' <hch@lst.de>,
	linux-fsdevel@vger.kernel.org, 'Jens Axboe' <axboe@fb.com>,
	'LKML' <linux-kernel@vger.kernel.org>
To: Jan Kara <jack@suse.cz>
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On 04/13/2015 03:21 PM, Jan Kara wrote:
<>
>> -struct backing_dev_info *inode_to_bdi(struct inode *inode);
>> +struct backing_dev_info *__inode_to_bdi(struct inode *inode);
>> +
>> +static inline
>> +struct backing_dev_info *inode_to_bdi(struct inode *inode)
>> +{
>> +	if (!inode || !inode->i_sb)
>> +		return __inode_to_bdi(inode);
>> +
>> +	return inode->i_sb->s_bdi;
>> +}
>   This is wrong for block-device inodes, isn't it?

Rrr yes my bad I meant

+struct backing_dev_info *inode_to_bdi(struct inode *inode)
+{
+	if (!inode || !inode->i_sb || !inode->i_sb->s_bdi)
+		return __inode_to_bdi(inode);
+
+	return inode->i_sb->s_bdi;
+}

I was hopping that blockdev_superblock->s_bdi == NULL
because what sb_is_blkdev_sb() is doing is checking
for blockdev_superblock.

>>From code audit I do not see where it might be set but
I might have missed it.

Thanks Jan
Boaz

> 
> 							Honza
>