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Subject: Re: [PATCH RFC v2 for-6.8/block 01/18] block: add some bdev apis
To: Jan Kara <jack@suse.cz>, Yu Kuai <yukuai1@huaweicloud.com>
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References: <20231211140552.973290-1-yukuai1@huaweicloud.com>
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From: Yu Kuai <yukuai1@huaweicloud.com>
Message-ID: <7d2bfa29-f93d-def2-80a3-72af063b36b3@huaweicloud.com>
Date: Tue, 12 Dec 2023 09:25:24 +0800
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Hi,

?? 2023/12/12 0:52, Jan Kara д??:
> On Mon 11-12-23 22:05:35, Yu Kuai wrote:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> Those apis will be used for other modules, so that bd_inode won't be
>> accessed directly from other modules.
>>
>> Signed-off-by: Yu Kuai <yukuai3@huawei.com>
> 
> ...
> 
>> +void bdev_associated_mapping(struct block_device *bdev,
>> +			     struct address_space *mapping)
>> +{
>> +	mapping->host = bdev->bd_inode;
>> +}
> 
> Here I'm not sure - is the helper really a win? It seems a bit obscure to
> me. This initialization of another mapping for a bdev looks really special.

Yes, I don't like this helper at all, but gfs2 is used this way, and I
need this helper to remove 'bd_inode' from block_devcie later. I'm not
familiar with gfs2 at all but perhaps it worth to dig deeper and figure
out a proper way for gfs2.

Thanks,
Kuai
> 
> 								Honza
>