From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754877AbcEXVLz (ORCPT ); Tue, 24 May 2016 17:11:55 -0400 Received: from mail.kernel.org ([198.145.29.136]:32938 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751148AbcEXVLy (ORCPT ); Tue, 24 May 2016 17:11:54 -0400 Date: Tue, 24 May 2016 16:11:49 -0500 From: Bjorn Helgaas To: Yongji Xie Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, iommu@lists.linux-foundation.org, alex.williamson@redhat.com, bhelgaas@google.com, aik@ozlabs.ru, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, joro@8bytes.org, warrier@linux.vnet.ibm.com, zhong@linux.vnet.ibm.com, nikunj@linux.vnet.ibm.com, eric.auger@linaro.org, will.deacon@arm.com, gwshan@linux.vnet.ibm.com, David.Laight@ACULAB.COM, alistair@popple.id.au, ruscur@russell.cc Subject: Re: [PATCH 2/5] iommu: Set PCI_BUS_FLAGS_MSI_REMAP if IOMMU have capability of IRQ remapping Message-ID: <20160524211149.GC16463@localhost> References: <1461761010-5452-1-git-send-email-xyjxie@linux.vnet.ibm.com> <1461761010-5452-3-git-send-email-xyjxie@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1461761010-5452-3-git-send-email-xyjxie@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 27, 2016 at 08:43:27PM +0800, Yongji Xie wrote: > The capability of IRQ remapping is abstracted on IOMMU side on > some archs. There is a existing flag IOMMU_CAP_INTR_REMAP for this. > > To have a universal flag to test this capability for different > archs on PCI side, we set PCI_BUS_FLAGS_MSI_REMAP for PCI buses > when IOMMU_CAP_INTR_REMAP is set. > > Signed-off-by: Yongji Xie > --- > drivers/iommu/iommu.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index 0e3b009..5d2b6f6 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -813,6 +813,16 @@ struct iommu_group *pci_device_group(struct device *dev) > return group; > } > > +static void pci_check_msi_remapping(struct pci_dev *pdev, > + const struct iommu_ops *ops) > +{ > + struct pci_bus *bus = pdev->bus; > + > + if (ops->capable(IOMMU_CAP_INTR_REMAP) && > + !(bus->bus_flags & PCI_BUS_FLAGS_MSI_REMAP)) > + bus->bus_flags |= PCI_BUS_FLAGS_MSI_REMAP; > +} This looks an awful lot like the pci_bus_check_msi_remapping() you add elsewhere. Why do we need both? > /** > * iommu_group_get_for_dev - Find or create the IOMMU group for a device > * @dev: target device > @@ -871,6 +881,9 @@ static int add_iommu_group(struct device *dev, void *data) > const struct iommu_ops *ops = cb->ops; > int ret; > > + if (dev_is_pci(dev) && ops->capable) > + pci_check_msi_remapping(to_pci_dev(dev), ops); > + > if (!ops->add_device) > return 0; > > @@ -913,6 +926,8 @@ static int iommu_bus_notifier(struct notifier_block *nb, > * result in ADD/DEL notifiers to group->notifier > */ > if (action == BUS_NOTIFY_ADD_DEVICE) { > + if (dev_is_pci(dev) && ops->capable) > + pci_check_msi_remapping(to_pci_dev(dev), ops); These calls don't smell right either. Why do we need dev_is_pci() checks here? Can't this be done in the PCI probe path somehow, e.g., in pci_set_bus_msi_domain() or something? > if (ops->add_device) > return ops->add_device(dev); > } else if (action == BUS_NOTIFY_REMOVED_DEVICE) { > -- > 1.7.9.5 >