From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF28AC433EF for ; Thu, 23 Sep 2021 06:35:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9C01A6109E for ; Thu, 23 Sep 2021 06:35:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239338AbhIWGhH (ORCPT ); Thu, 23 Sep 2021 02:37:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:44534 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239312AbhIWGhG (ORCPT ); Thu, 23 Sep 2021 02:37:06 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id EFE0F6103D; Thu, 23 Sep 2021 06:35:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1632378935; bh=DEKVsUEz3rB/lWfDPCmtwUG21EgoliQ4AdWEdVy1G4U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TYUzK6CIkvGFuMRyNE99h2HYsmLBhwlwdophnZordr6fK3vWI6QJ9YcWz2N4XDaab 3qUohiEm+tsTsS+R3ftMBKqBt3PIubaDE3FGnu5HRSE8GPA7wV3dDIC21aSAZihvgy zO5z/S+AYuWJic/RgUSDTj8REgFAgMbf7xzxlOngNezsYacei0HI12BT1iGEAwqxmA SPycfdhf0XK/VvZSWAu+cBsqq0pcpbo/BAj5tEVydyxYY/lfV9gJh5UZY+26l32f7B z7gZwU5EHhV+G/MKWDkxzjHMhTXcV6EpKwLwsXLGymVQRSPXntArvr/W3vHeix2gLs c+0W+FZoW5BMA== Date: Thu, 23 Sep 2021 09:35:32 +0300 From: Leon Romanovsky To: Bjorn Helgaas Cc: Doug Ledford , Jason Gunthorpe , Alex Williamson , Bjorn Helgaas , "David S. Miller" , Jakub Kicinski , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-rdma@vger.kernel.org, netdev@vger.kernel.org, Saeed Mahameed , Yishai Hadas Subject: Re: [PATCH mlx5-next 1/7] PCI/IOV: Provide internal VF index Message-ID: References: <8d5bba9a6a1067989c3291fa2929528578812334.1632305919.git.leonro@nvidia.com> <20210922215930.GA231505@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210922215930.GA231505@bhelgaas> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Sep 22, 2021 at 04:59:30PM -0500, Bjorn Helgaas wrote: > On Wed, Sep 22, 2021 at 01:38:50PM +0300, Leon Romanovsky wrote: > > From: Jason Gunthorpe > > > > The PCI core uses the VF index internally, often called the vf_id, > > during the setup of the VF, eg pci_iov_add_virtfn(). > > > > This index is needed for device drivers that implement live migration > > for their internal operations that configure/control their VFs. > > > > Specifically, mlx5_vfio_pci driver that is introduced in coming patches > > from this series needs it and not the bus/device/function which is > > exposed today. > > > > Add pci_iov_vf_id() which computes the vf_id by reversing the math that > > was used to create the bus/device/function. > > > > Signed-off-by: Yishai Hadas > > Signed-off-by: Jason Gunthorpe > > Signed-off-by: Leon Romanovsky > > Acked-by: Bjorn Helgaas > > mlx5_core_sriov_set_msix_vec_count() looks like it does basically the > same thing as pci_iov_vf_id() by iterating through VFs until it finds > one with a matching devfn (although it *doesn't* check for a matching > bus number, which seems like a bug). > > Maybe that should use pci_iov_vf_id()? Yes, I gave same comment internally and we decided to simply reduce the amount of changes in mlx5_core to have less distractions and submit as a followup. Most likely will add this hunk in v1. diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sriov.c b/drivers/net/ethernet/mellanox/mlx5/core/sriov.c index e8185b69ac6c..b66be0b4244a 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/sriov.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/sriov.c @@ -209,15 +209,8 @@ int mlx5_core_sriov_set_msix_vec_count(struct pci_dev *vf, int msix_vec_count) /* Reversed translation of PCI VF function number to the internal * function_id, which exists in the name of virtfn symlink. */ - for (id = 0; id < pci_num_vf(pf); id++) { - if (!sriov->vfs_ctx[id].enabled) - continue; - - if (vf->devfn == pci_iov_virtfn_devfn(pf, id)) - break; - } - - if (id == pci_num_vf(pf) || !sriov->vfs_ctx[id].enabled) + id = pci_iov_vf_id(vf); + if (id < 0 || !sriov->vfs_ctx[id].enabled) return -EINVAL; return mlx5_set_msix_vec_count(dev, id + 1, msix_vec_count); Thanks > > > --- > > drivers/pci/iov.c | 14 ++++++++++++++ > > include/linux/pci.h | 7 ++++++- > > 2 files changed, 20 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c > > index dafdc652fcd0..e7751fa3fe0b 100644 > > --- a/drivers/pci/iov.c > > +++ b/drivers/pci/iov.c > > @@ -33,6 +33,20 @@ int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id) > > } > > EXPORT_SYMBOL_GPL(pci_iov_virtfn_devfn); > > > > +int pci_iov_vf_id(struct pci_dev *dev) > > +{ > > + struct pci_dev *pf; > > + > > + if (!dev->is_virtfn) > > + return -EINVAL; > > + > > + pf = pci_physfn(dev); > > + return (((dev->bus->number << 8) + dev->devfn) - > > + ((pf->bus->number << 8) + pf->devfn + pf->sriov->offset)) / > > + pf->sriov->stride; > > +} > > +EXPORT_SYMBOL_GPL(pci_iov_vf_id); > > + > > /* > > * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may > > * change when NumVFs changes. > > diff --git a/include/linux/pci.h b/include/linux/pci.h > > index cd8aa6fce204..4d6c73506e18 100644 > > --- a/include/linux/pci.h > > +++ b/include/linux/pci.h > > @@ -2153,7 +2153,7 @@ void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar); > > #ifdef CONFIG_PCI_IOV > > int pci_iov_virtfn_bus(struct pci_dev *dev, int id); > > int pci_iov_virtfn_devfn(struct pci_dev *dev, int id); > > - > > +int pci_iov_vf_id(struct pci_dev *dev); > > int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn); > > void pci_disable_sriov(struct pci_dev *dev); > > > > @@ -2181,6 +2181,11 @@ static inline int pci_iov_virtfn_devfn(struct pci_dev *dev, int id) > > { > > return -ENOSYS; > > } > > +static inline int pci_iov_vf_id(struct pci_dev *dev) > > +{ > > + return -ENOSYS; > > +} > > + > > Drop the blank line to match the surrounding stubs. Sure, thanks > > > static inline int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) > > { return -ENODEV; } >