From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lorenzo Pieralisi Subject: Re: [PATCH v2 2/2] hv_netvsc: pair VF based on serial number Date: Thu, 20 Sep 2018 14:43:00 +0100 Message-ID: <20180920134300.GC838@e107981-ln.cambridge.arm.com> References: <20180914195457.20433-1-sthemmin@microsoft.com> <20180914195457.20433-3-sthemmin@microsoft.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, devel@linuxdriverproject.org, netdev@vger.kernel.org, linux-pci@vger.kernel.org To: Stephen Hemminger Return-path: Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:46142 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732302AbeITT0i (ORCPT ); Thu, 20 Sep 2018 15:26:38 -0400 Content-Disposition: inline In-Reply-To: <20180914195457.20433-3-sthemmin@microsoft.com> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Sep 14, 2018 at 12:54:57PM -0700, Stephen Hemminger wrote: > Matching network device based on MAC address is problematic > since a non VF network device can be creted with a duplicate MAC > address causing confusion and problems. The VMBus API does provide > a serial number that is a better matching method. > > Signed-off-by: Stephen Hemminger > --- > drivers/net/hyperv/netvsc.c | 3 ++ > drivers/net/hyperv/netvsc_drv.c | 58 +++++++++++++++++++-------------- > 2 files changed, 36 insertions(+), 25 deletions(-) > > diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c > index 31c3d77b4733..fe01e141c8f8 100644 > --- a/drivers/net/hyperv/netvsc.c > +++ b/drivers/net/hyperv/netvsc.c > @@ -1203,6 +1203,9 @@ static void netvsc_send_vf(struct net_device *ndev, > > net_device_ctx->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated; > net_device_ctx->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial; > + netdev_info(ndev, "VF slot %u %s\n", > + net_device_ctx->vf_serial, > + net_device_ctx->vf_alloc ? "added" : "removed"); > } > > static void netvsc_receive_inband(struct net_device *ndev, > diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c > index 1121a1ec407c..9dedc1463e88 100644 > --- a/drivers/net/hyperv/netvsc_drv.c > +++ b/drivers/net/hyperv/netvsc_drv.c > @@ -1894,20 +1894,6 @@ static void netvsc_link_change(struct work_struct *w) > rtnl_unlock(); > } > > -static struct net_device *get_netvsc_bymac(const u8 *mac) > -{ > - struct net_device_context *ndev_ctx; > - > - list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) { > - struct net_device *dev = hv_get_drvdata(ndev_ctx->device_ctx); > - > - if (ether_addr_equal(mac, dev->perm_addr)) > - return dev; > - } > - > - return NULL; > -} > - > static struct net_device *get_netvsc_byref(struct net_device *vf_netdev) > { > struct net_device_context *net_device_ctx; > @@ -2036,26 +2022,48 @@ static void netvsc_vf_setup(struct work_struct *w) > rtnl_unlock(); > } > > +/* Find netvsc by VMBus serial number. > + * The PCI hyperv controller records the serial number as the slot. > + */ > +static struct net_device *get_netvsc_byslot(const struct net_device *vf_netdev) > +{ > + struct device *parent = vf_netdev->dev.parent; > + struct net_device_context *ndev_ctx; > + struct pci_dev *pdev; > + > + if (!parent || !dev_is_pci(parent)) > + return NULL; /* not a PCI device */ > + > + pdev = to_pci_dev(parent); > + if (!pdev->slot) { > + netdev_notice(vf_netdev, "no PCI slot information\n"); > + return NULL; > + } > + > + list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) { > + if (!ndev_ctx->vf_alloc) > + continue; > + > + if (ndev_ctx->vf_serial == pdev->slot->number) > + return hv_get_drvdata(ndev_ctx->device_ctx); In patch 1, pdev->slot->number is set to: PCI_SLOT(wslot_to_devfn(hpdev->desc.win_slot.slot)) so I assume vf_serial is initialized (I have no knowledge of VMBUS and hyper-V internals) to that value, somehow. I also do not know how the wslot stuff is handled but I assume 5 bits (ie dev bits in devfn) are enough. BTW, I have noticed this patch (and patch 1) are already in -next so I will drop them from the PCI patch queue. Lorenzo > + } > + > + netdev_notice(vf_netdev, > + "no netdev found for slot %u\n", pdev->slot->number); > + return NULL; > +} > + > static int netvsc_register_vf(struct net_device *vf_netdev) > { > - struct net_device *ndev; > struct net_device_context *net_device_ctx; > - struct device *pdev = vf_netdev->dev.parent; > struct netvsc_device *netvsc_dev; > + struct net_device *ndev; > int ret; > > if (vf_netdev->addr_len != ETH_ALEN) > return NOTIFY_DONE; > > - if (!pdev || !dev_is_pci(pdev) || dev_is_pf(pdev)) > - return NOTIFY_DONE; > - > - /* > - * We will use the MAC address to locate the synthetic interface to > - * associate with the VF interface. If we don't find a matching > - * synthetic interface, move on. > - */ > - ndev = get_netvsc_bymac(vf_netdev->perm_addr); > + ndev = get_netvsc_byslot(vf_netdev); > if (!ndev) > return NOTIFY_DONE; > > -- > 2.18.0 >