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Subject: Re: [PATCH] [UBI] 1/5 - UBI notifications, take two
From: Artem Bityutskiy <dedekind@infradead.org>
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Date: Thu, 18 Dec 2008 13:14:30 +0200
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On Thu, 2008-12-18 at 13:11 +0200, Artem Bityutskiy wrote:
> > > > The ubi_enum_volumes could open the volume with the flag
> > > > UBI_OPEN_INTERNAL and thus release spinlock when calling notifiers.
> > >=20
> > > You may introduce a "ubi_get_volume(struct ubi_info *ubi, int vol_id)=
"
> > > function, similar to the existing "ubi_get_device(int ubi_num)"
> > > function. However, it looks like you may just use UBI_READONLY instea=
d.
> > > It will not prevent the "notifyees" to open the volume in UBI_READWRI=
TE
> > > mode.
> > But will prevent opening in UBI_EXCLUSIVE. OK, get_volume/put_volume
> > looks as the right way to go.
>=20
> It will prevent exlusive, as well as get/put must prevent exclusive, so
> there should be no difference for you at all. Exclusive is used when the
> module is removed or re-sized, and there must be zero users if these
> operations are performed.

IOW, these get/put volume calls should not bring any value for you and
seem to be unnecessary.

--=20
Best regards,
Artem Bityutskiy (=D0=91=D0=B8=D1=82=D1=8E=D1=86=D0=BA=D0=B8=D0=B9 =D0=90=
=D1=80=D1=82=D1=91=D0=BC)