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Date:   Mon, 16 Sep 2019 05:00:32 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Matthew Bobrowski <mbobrowski@mbobrowski.org>
Cc:     tytso@mit.edu, jack@suse.cz, adilger.kernel@dilger.ca,
        linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        david@fromorbit.com, hch@infradead.org, darrick.wong@oracle.com
Subject: Re: [PATCH v3 1/6] ext4: introduce direct IO read path using iomap
 infrastructure
Message-ID: <20190916120032.GA4005@infradead.org>
References: <cover.1568282664.git.mbobrowski@mbobrowski.org>
 <532d8deae8e522a27539470457eec6b1a5683127.1568282664.git.mbobrowski@mbobrowski.org>
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On Thu, Sep 12, 2019 at 09:03:44PM +1000, Matthew Bobrowski wrote:
> +static bool ext4_dio_checks(struct inode *inode)
> +{
> +#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
> +	if (IS_ENCRYPTED(inode))
> +		return false;
> +#endif
> +	if (ext4_should_journal_data(inode))
> +		return false;
> +	if (ext4_has_inline_data(inode))
> +		return false;
> +	return true;

Shouldn't this function be called ext4_dio_supported or similar?

Also bonus points of adding a patch that defines a IS_ENCRYPTED stub
for !CONFIG_FS_ENCRYPTION to make this a little cleaner.

Also the iomap direct I/O code supports inline data, so the above
might not be required (at least with small updates elsewhere).