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Date: Wed, 25 Sep 1996 03:19:24 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199609241719.DAA07851@godzilla.zeta.org.au>
To: dfr@render.com, michaelh@cet.co.jp
Subject: Re: New d_type field in *devsw
Cc: bde@zeta.org.au, fs@FreeBSD.org, lite2@FreeBSD.org
Sender: owner-fs@FreeBSD.org
X-Loop: FreeBSD.org
Precedence: bulk

>There is an existing unused field in bdevsw, d_flags which can be used to
>identify disks and tapes for securelevel and ioctl or alternatively the
>existing FreeBSD behaviour of calling isdisk() is still possible.  The
>current behaviour of dead_read is probably also adequate.

>Needless to say, these hacks should be first against the wall after the
>devfs revolution :-).

They are high quality compared with isdisk().

The cross pointers in the devsw's can be be used to share d_flags with
the cdevs.  However, to use them we would have to modify a lot of
device drivers with a temporary change.

Bruce