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Date:   Mon, 21 Jan 2019 09:44:36 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     dsterba@suse.cz,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Chris Mason <clm@fb.com>, Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>,
        Lu Fengqi <lufq.fnst@cn.fujitsu.com>,
        linux-btrfs@vger.kernel.org, Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH v1] Btrfs: Switch to use new generic UUID API
Message-ID: <20190121084436.GC18680@lst.de>
References: <20190110181653.66048-1-andriy.shevchenko@linux.intel.com> <20190111134803.GB27146@twin.jikos.cz>
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On Fri, Jan 11, 2019 at 02:48:03PM +0100, David Sterba wrote:
> >  	if (is_fstree(objectid))
> > -		uuid_le_gen(&uuid);
> > -	memcpy(root->root_item.uuid, uuid.b, BTRFS_UUID_SIZE);
> > +		guid_gen((guid_t *)&root->root_item.uuid);
> > +	else
> > +		guid_copy((guid_t *)&root->root_item.uuid, &guid_null);
> 
> I don't like the type casts, a simple wrapper would be better I think.

It seems like we should use the guid_t type in the actual strutures
instead of doing this casting.  Andy, is there any reason I'm missing
why we can't do that in btrfs?