From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-2.mimecast.com ([205.139.110.61]:31778 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729156AbgBNML6 (ORCPT ); Fri, 14 Feb 2020 07:11:58 -0500 Date: Fri, 14 Feb 2020 13:11:47 +0100 From: Cornelia Huck Subject: Re: [RFC PATCH v2 2/9] vfio-ccw: Register a chp_event callback for vfio-ccw Message-ID: <20200214131147.0a98dd7d.cohuck@redhat.com> In-Reply-To: <20200206213825.11444-3-farman@linux.ibm.com> References: <20200206213825.11444-1-farman@linux.ibm.com> <20200206213825.11444-3-farman@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Eric Farman Cc: Halil Pasic , Jason Herne , Jared Rossi , linux-s390@vger.kernel.org, kvm@vger.kernel.org On Thu, 6 Feb 2020 22:38:18 +0100 Eric Farman wrote: > From: Farhan Ali > > Register the chp_event callback to receive channel path related > events for the subchannels managed by vfio-ccw. I'm wondering how useful this patch would be on its own. > > Signed-off-by: Farhan Ali > Signed-off-by: Eric Farman > --- > > Notes: > v1->v2: > - Move s390dbf before cio_update_schib() call [CH] > > v0->v1: [EF] > - Add s390dbf trace > > drivers/s390/cio/vfio_ccw_drv.c | 44 +++++++++++++++++++++++++++++++++ > 1 file changed, 44 insertions(+) > (...) > @@ -257,6 +258,48 @@ static int vfio_ccw_sch_event(struct subchannel *sch, int process) > return rc; > } > > +static int vfio_ccw_chp_event(struct subchannel *sch, > + struct chp_link *link, int event) > +{ > + struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev); > + int mask = chp_ssd_get_mask(&sch->ssd_info, link); > + int retry = 255; > + > + if (!private || !mask) > + return 0; > + > + VFIO_CCW_MSG_EVENT(2, "%pUl (%x.%x.%04x): mask=0x%x event=%d\n", > + mdev_uuid(private->mdev), sch->schid.cssid, > + sch->schid.ssid, sch->schid.sch_no, > + mask, event); > + > + if (cio_update_schib(sch)) > + return -ENODEV; > + > + switch (event) { > + case CHP_VARY_OFF: > + /* Path logically turned off */ > + sch->opm &= ~mask; > + sch->lpm &= ~mask; > + break; > + case CHP_OFFLINE: > + /* Path is gone */ > + cio_cancel_halt_clear(sch, &retry); Any reason you do this only for CHP_OFFLINE and not for CHP_VARY_OFF? > + break; > + case CHP_VARY_ON: > + /* Path logically turned on */ > + sch->opm |= mask; > + sch->lpm |= mask; > + break; > + case CHP_ONLINE: > + /* Path became available */ > + sch->lpm |= mask & sch->opm; If I'm not mistaken, this patch introduces the first usage of sch->opm in the vfio-ccw code. Are we missing something? Or am I missing something? :) > + break; > + } > + > + return 0; > +} > + > static struct css_device_id vfio_ccw_sch_ids[] = { > { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, }, > { /* end of list */ }, (...)