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Date:   Thu, 29 Aug 2019 23:41:37 +0800
From:   Gao Xiang <gaoxiang25@huawei.com>
To:     Christoph Hellwig <hch@infradead.org>
CC:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        Theodore Ts'o <tytso@mit.edu>, "Pavel Machek" <pavel@denx.de>,
        David Sterba <dsterba@suse.cz>,
        Amir Goldstein <amir73il@gmail.com>,
        "Darrick J . Wong" <darrick.wong@oracle.com>,
        "Dave Chinner" <david@fromorbit.com>,
        Jaegeuk Kim <jaegeuk@kernel.org>, Jan Kara <jack@suse.cz>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        <linux-fsdevel@vger.kernel.org>, <devel@driverdev.osuosl.org>,
        LKML <linux-kernel@vger.kernel.org>,
        <linux-erofs@lists.ozlabs.org>, Chao Yu <yuchao0@huawei.com>,
        Miao Xie <miaoxie@huawei.com>,
        Li Guifu <bluce.liguifu@huawei.com>,
        Fang Wei <fangwei1@huawei.com>
Subject: Re: [PATCH v6 01/24] erofs: add on-disk layout
Message-ID: <20190829154136.GA129582@architecture4>
References: <20190802125347.166018-1-gaoxiang25@huawei.com>
 <20190802125347.166018-2-gaoxiang25@huawei.com>
 <20190829095954.GB20598@infradead.org>
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Hi Christoph,

On Thu, Aug 29, 2019 at 02:59:54AM -0700, Christoph Hellwig wrote:

[]

> 
> > +static bool erofs_inode_is_data_compressed(unsigned int datamode)
> > +{
> > +	if (datamode == EROFS_INODE_FLAT_COMPRESSION)
> > +		return true;
> > +	return datamode == EROFS_INODE_FLAT_COMPRESSION_LEGACY;
> > +}
> 
> This looks like a really obsfucated way to write:
> 
> 	return datamode == EROFS_INODE_FLAT_COMPRESSION ||
> 		datamode == EROFS_INODE_FLAT_COMPRESSION_LEGACY;

Add a word about this, the above approach is not horrible if more
datamode add here and comments, e.g

static bool erofs_inode_is_data_compressed(unsigned int datamode)
{
	/* has z_erofs_map_header */
	if (datamode == EROFS_INODE_FLAT_COMPRESSION)
		return true;
	/* some blablabla */
	if (datamode == (1) )
		return true;
	/* some blablablabla */
	if (datamode == (2) )
		return true;
	/* no z_erofs_map_header */
	return datamode == EROFS_INODE_FLAT_COMPRESSION_LEGACY;
}

vs.

static bool erofs_inode_is_data_compressed(unsigned int datamode)
{
	/* has z_erofs_map_header */
	return datamode == EROFS_INODE_FLAT_COMPRESSION ||
		/* some blablabla */
	       datamode == (1) ||
	       	/* some blablablabla */
	       datamode == (2) ||
	        /* no z_erofs_map_header */
	       datamode == EROFS_INODE_FLAT_COMPRESSION_LEGACY;
}

I have no idea which one is better.
Anyway, if you still like the form, I will change it.

Thanks,
Gao Xiang