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Message-ID: <1ba0f002-42c7-b085-0c54-6071664ba79b@kernel.org>
Date:   Thu, 2 Dec 2021 22:04:11 +0800
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Subject: Re: [f2fs-dev] [PATCH 5/6] f2fs: implement iomap operations
Content-Language: en-US
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     Jaegeuk Kim <jaegeuk@kernel.org>, linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
References: <20211116214510.2934905-1-jaegeuk@kernel.org>
 <20211116214510.2934905-5-jaegeuk@kernel.org>
 <b36e2d44-4834-3931-6a32-4fa52d1d7785@kernel.org>
 <YahIf3UlhuxJT1O4@sol.localdomain>
From:   Chao Yu <chao@kernel.org>
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On 2021/12/2 12:15, Eric Biggers wrote:
> On Thu, Dec 02, 2021 at 11:10:41AM +0800, Chao Yu wrote:
>> Why not relocating this check before f2fs_map_blocks()?

Wait, it supports DIO in multi-device image after commit 	71f2c8206202 
("f2fs: multidevice: support direct IO"), how about
checking with f2fs_allow_multi_device_dio()?

Thanks,

>>
>> Thanks,
>>
>>> +		iomap->bdev = inode->i_sb->s_bdev;
> 
> Are you talking about the check for !f2fs_is_multi_device()?  It could go in
> either location, but I think it makes the most sense to have it right before the
> line that uses 'inode->i_sb->s_bdev', since that is the place which makes the
> assumption that the filesystem has only one block device.
> 
> - Eric
>