RE: [PATCH 7/8] PCI: replace stray uses of PCI_{DEVFN,BDF}2()

["Tian, Kevin" <kevin.tian@xxxxxxxxx>]

> From: Jan Beulich <jbeulich@xxxxxxxx>
> Sent: Monday, April 11, 2022 5:40 PM
> 
> There's no good reason to use these when we already have a pci_sbdf_t
> type object available. This extends to the use of PCI_BUS() in
> pci_ecam_map_bus() as well.
> 
> No change to generated code (with gcc11 at least, and I have to admit
> that I didn't expect compilers to necessarily be able to spot the
> optimization potential on the original code).
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>

> ---
> Note that the Arm changes are "blind": I haven't been able to spot a way
> to at least compile test the changes there; the code looks to be
> entirely dead.
> 
> --- a/xen/arch/arm/pci/ecam.c
> +++ b/xen/arch/arm/pci/ecam.c
> @@ -28,8 +28,7 @@ void __iomem *pci_ecam_map_bus(struct pc
>          container_of(bridge->ops, const struct pci_ecam_ops, pci_ops);
>      unsigned int devfn_shift = ops->bus_shift - 8;
>      void __iomem *base;
> -
> -    unsigned int busn = PCI_BUS(sbdf.bdf);
> +    unsigned int busn = sbdf.bus;
> 
>      if ( busn < cfg->busn_start || busn > cfg->busn_end )
>          return NULL;
> @@ -37,7 +36,7 @@ void __iomem *pci_ecam_map_bus(struct pc
>      busn -= cfg->busn_start;
>      base = cfg->win + (busn << ops->bus_shift);
> 
> -    return base + (PCI_DEVFN2(sbdf.bdf) << devfn_shift) + where;
> +    return base + (sbdf.df << devfn_shift) + where;
>  }
> 
>  bool __init pci_ecam_need_p2m_hwdom_mapping(struct domain *d,
> --- a/xen/arch/x86/msi.c
> +++ b/xen/arch/x86/msi.c
> @@ -839,7 +839,7 @@ static int msix_capability_init(struct p
>              pbus = dev->info.physfn.bus;
>              pslot = PCI_SLOT(dev->info.physfn.devfn);
>              pfunc = PCI_FUNC(dev->info.physfn.devfn);
> -            vf = PCI_BDF2(dev->bus, dev->devfn);
> +            vf = dev->sbdf.bdf;
>          }
> 
>          table_paddr = read_pci_mem_bar(seg, pbus, pslot, pfunc, bir, vf);
> --- a/xen/drivers/passthrough/vtd/qinval.c
> +++ b/xen/drivers/passthrough/vtd/qinval.c
> @@ -267,7 +267,7 @@ int qinval_device_iotlb_sync(struct vtd_
>      qinval_entry->q.dev_iotlb_inv_dsc.lo.res_1 = 0;
>      qinval_entry->q.dev_iotlb_inv_dsc.lo.max_invs_pend = pdev-
> >ats.queue_depth;
>      qinval_entry->q.dev_iotlb_inv_dsc.lo.res_2 = 0;
> -    qinval_entry->q.dev_iotlb_inv_dsc.lo.sid = PCI_BDF2(pdev->bus, pdev-
> >devfn);
> +    qinval_entry->q.dev_iotlb_inv_dsc.lo.sid = pdev->sbdf.bdf;
>      qinval_entry->q.dev_iotlb_inv_dsc.lo.res_3 = 0;
> 
>      qinval_entry->q.dev_iotlb_inv_dsc.hi.size = size;