On Wed, Oct 13, 2021 at 12:46:55PM +0300, Yishai Hadas wrote: > From: Jason Gunthorpe <jgg@xxxxxxxxxx> > > 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 <yishaih@xxxxxxxxxx> > Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> > Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx> I already acked this: https://lore.kernel.org/r/20210922215930.GA231505@bhelgaas Saves me time if you carry the ack so I don't have to look at this again. But since I *am* looking at it again, I think it's nice if the subject line includes the actual interface you're adding, e.g., PCI/IOV: Add pci_iov_vf_id() to get VF index > --- > drivers/pci/iov.c | 14 ++++++++++++++ > include/linux/pci.h | 8 +++++++- > 2 files changed, 21 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..2337512e67f0 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 +2181,12 @@ 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; > +} > + > static inline int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) > { return -ENODEV; } > > -- > 2.18.1 >
