From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre Morel Subject: Re: [PATCH v4 3/7] s390: ap: associate a ap_vfio_queue and a matrix mdev Date: Wed, 27 Feb 2019 11:21:32 +0100 Message-ID: References: <1550849400-27152-1-git-send-email-pmorel@linux.ibm.com> <1550849400-27152-4-git-send-email-pmorel@linux.ibm.com> <20190227103211.5e4d63b2.cohuck@redhat.com> Reply-To: pmorel@linux.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190227103211.5e4d63b2.cohuck@redhat.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Cornelia Huck Cc: borntraeger@de.ibm.com, alex.williamson@redhat.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, frankja@linux.ibm.com, akrowiak@linux.ibm.com, pasic@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, freude@linux.ibm.com, mimu@linux.ibm.com List-ID: On 27/02/2019 10:32, Cornelia Huck wrote: > On Fri, 22 Feb 2019 16:29:56 +0100 > Pierre Morel wrote: > >> We need to associate the ap_vfio_queue, which will hold the >> per queue information for interrupt with a matrix mediated device >> which hold the configuration and the way to the CRYCB. >> >> Let's do this when assigning a APID or a APQI to the mediated device >> and clear the relation when unassigning. >> >> Queuing the devices on a list of free devices and testing the >> matrix_mdev pointer to the associated matrix allow us to know >> if the queue is associated to the matrix device and associated >> or not to a mediated device. >> >> When resetting an AP queue we must wait until there are no more >> messages in the message queue before considering the queue is really >> in a clean state. >> >> Let's do it and wait until the status response code indicate the >> queue is empty after issuing a PAPQ/ZAPQ instruction. > > I'm a bit confused about the context where that list moving etc. is > supposed to take place. > > When are we assigning/deassigning? Is there even supposed to be any > activity that we need to zap on the queues? > > Do we need any serialization/locking on the lists? Did I really forget this!? Yes, thanks. Regards, Pierre -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany