Date: Thu, 19 Feb 2009 22:09:43 +0100 From: Ed Schouten <ed@80386.nl> To: Roman Divacky <rdivacky@FreeBSD.org> Subject: Re: Making Linux stat() less evil Message-ID: <20090219210943.GG19161@hoeg.nl> Resent-Message-ID: <20090219211001.GH19161@hoeg.nl> In-Reply-To: <20090219205653.GA78242@freebsd.org> References: <20090219205645.GF19161@hoeg.nl> <20090219205653.GA78242@freebsd.org>
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* Roman Divacky <rdivacky@FreeBSD.org> wrote:
> why cant you use kern_statat() and perform this after it returns?
>=20
> + if (S_ISCHR(sb.st_mode) && nd.ni_vp->v_un.vu_cdev !=3D NULL &&
> + linux_driver_get_major_minor(
> + nd.ni_vp->v_un.vu_cdev->si_name, &major, &minor) =3D=3D 0) {
> + sb.st_rdev =3D (major << 8 | minor);
> + }
Because I want to use the vnode used by kern_statat() directly. If we
perform a second lookup after the call to kern_statat(), it's a race.
There is no guarantee you're looking at the same vnode.
--=20
Ed Schouten <ed@80386.nl>
WWW: http://80386.nl/
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