From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (cantor2.suse.de [195.135.220.15]) (using TLSv1 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4313F1A0892 for ; Tue, 20 May 2014 21:44:27 +1000 (EST) Message-ID: <537B4015.7030404@suse.de> Date: Tue, 20 May 2014 13:44:21 +0200 From: Alexander Graf MIME-Version: 1.0 To: Gavin Shan Subject: Re: [PATCH 3/4] drivers/vfio: New IOCTL command VFIO_EEH_INFO References: <1400574612-19411-1-git-send-email-gwshan@linux.vnet.ibm.com> <1400574612-19411-4-git-send-email-gwshan@linux.vnet.ibm.com> <537B3AA7.7040106@suse.de> <537B3C68.8080102@suse.de> <20140520114031.GA20397@shangw> In-Reply-To: <20140520114031.GA20397@shangw> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: aik@ozlabs.ru, kvm-ppc@vger.kernel.org, alex.williamson@redhat.com, qiudayu@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 20.05.14 13:40, Gavin Shan wrote: > On Tue, May 20, 2014 at 01:28:40PM +0200, Alexander Graf wrote: >> On 20.05.14 13:21, Alexander Graf wrote: >>> On 20.05.14 10:30, Gavin Shan wrote: >>>> The patch adds new IOCTL command VFIO_EEH_OP to VFIO PCI device >>>> to support EEH functionality for PCI devices, which have been >>>> passed from host to guest via VFIO. >>>> >>>> Signed-off-by: Gavin Shan >>>> --- >>>> arch/powerpc/platforms/powernv/Makefile | 1 + >>>> arch/powerpc/platforms/powernv/eeh-vfio.c | 445 >>>> ++++++++++++++++++++++++++++++ >>>> drivers/vfio/pci/vfio_pci.c | 24 +- >>>> drivers/vfio/pci/vfio_pci_private.h | 16 ++ >>>> include/uapi/linux/vfio.h | 43 +++ >>>> 5 files changed, 523 insertions(+), 6 deletions(-) >>>> create mode 100644 arch/powerpc/platforms/powernv/eeh-vfio.c >>> Why doesn't this code live inside the vfio module? If I don't load >>> the vfio module, I don't need that code to waste memory in my >>> kernel, no? > Yes, It saves some memory. > >> So I think from a modeling point of view, you want VFIO code that >> calls reasonably generic helpers inside the kernel to deal with >> errors. >> >> The "generic helpers" don't have anything to do with VFIO. Everything >> that interfaces via ioctls with user space is 100% VFIO code. >> >> The latter should be tristate inside vfio.ko, the former can be =y. >> > The main reason I put eeh-vfio.c to arch/powerpc/platforms/powernv/ is > the source file needs access data structures (struct pnv_phb) defined > in "pci.h" under that directory. Then create a good in-kernel framework from that directory and make use of it from the VFIO code :). But please don't mesh together VFIO, powernv EEH handling and RTAS. Alex