From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:41128 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726434AbgISPuc (ORCPT ); Sat, 19 Sep 2020 11:50:32 -0400 Subject: Re: [PATCH 0/4] Pass zPCI hardware information via VFIO From: Matthew Rosato References: <1600529318-8996-1-git-send-email-mjrosato@linux.ibm.com> Message-ID: <1f47cab8-af05-494f-1cf0-7b6d126e6367@linux.ibm.com> Date: Sat, 19 Sep 2020 11:50:25 -0400 MIME-Version: 1.0 In-Reply-To: <1600529318-8996-1-git-send-email-mjrosato@linux.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit List-ID: To: alex.williamson@redhat.com, cohuck@redhat.com, schnelle@linux.ibm.com Cc: pmorel@linux.ibm.com, borntraeger@de.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com, gerald.schaefer@linux.ibm.com, linux-s390@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org On 9/19/20 11:28 AM, Matthew Rosato wrote: > This patchset provides a means by which hardware information about the > underlying PCI device can be passed up to userspace (ie, QEMU) so that > this hardware information can be used rather than previously hard-coded > assumptions. A new VFIO region type is defined which holds this > information. > > A form of these patches saw some rounds last year but has been back- > tabled for a while. The original work for this feature was done by Pierre > Morel. I'd like to refresh the discussion on this and get this finished up > so that we can move forward with better-supporting additional types of > PCI-attached devices. The proposal here presents a completely different > region mapping vs the prior approach, taking inspiration from vfio info > capability chains to provide device CLP information in a way that allows > for future expansion (new CLP features). > > This feature is toggled via the CONFIG_VFIO_PCI_ZDEV configuration entry. QEMU patchset that exploits the new region: https://lists.gnu.org/archive/html/qemu-devel/2020-09/msg07076.html > > Matthew Rosato (4): > s390/pci: stash version in the zpci_dev > s390/pci: track whether util_str is valid in the zpci_dev > vfio-pci/zdev: define the vfio_zdev header > vfio-pci/zdev: use a device region to retrieve zPCI information > > arch/s390/include/asm/pci.h | 4 +- > arch/s390/pci/pci_clp.c | 2 + > drivers/vfio/pci/Kconfig | 13 ++ > drivers/vfio/pci/Makefile | 1 + > drivers/vfio/pci/vfio_pci.c | 8 ++ > drivers/vfio/pci/vfio_pci_private.h | 10 ++ > drivers/vfio/pci/vfio_pci_zdev.c | 242 ++++++++++++++++++++++++++++++++++++ > include/uapi/linux/vfio.h | 5 + > include/uapi/linux/vfio_zdev.h | 116 +++++++++++++++++ > 9 files changed, 400 insertions(+), 1 deletion(-) > create mode 100644 drivers/vfio/pci/vfio_pci_zdev.c > create mode 100644 include/uapi/linux/vfio_zdev.h >