[Very RFC 33/46] powernv/pci: Remove open-coded PE lookup in iommu notifier

[Alexey Kardashevskiy]

On 20/11/2019 12:28, Oliver O'Halloran wrote:
> Signed-off-by: Oliver O'Halloran <oohall at gmail.com>
> ---
>  arch/powerpc/platforms/powernv/pci.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
> index 5b1f4677cdce..0eeea8652426 100644
> --- a/arch/powerpc/platforms/powernv/pci.c
> +++ b/arch/powerpc/platforms/powernv/pci.c
> @@ -943,23 +943,22 @@ static int pnv_tce_iommu_bus_notifier(struct notifier_block *nb,
>  {
>  	struct device *dev = data;
>  	struct pci_dev *pdev;
> -	struct pci_dn *pdn;
>  	struct pnv_ioda_pe *pe;
>  	struct pnv_phb *phb;
>  
>  	switch (action) {
>  	case BUS_NOTIFY_ADD_DEVICE:
>  		pdev = to_pci_dev(dev);
> -		pdn = pci_get_pdn(pdev);
>  		phb = pci_bus_to_pnvhb(pdev->bus);
>  
>  		WARN_ON_ONCE(!phb);
> -		if (!pdn || pdn->pe_number == IODA_INVALID_PE || !phb)
> +		if (!phb)
>  			return 0;

This check is weird - the function does not use @phb anymore, it would
make more sense if pnv_ioda_get_pe() checked phb!=NULL.


>  
> -		pe = &phb->ioda.pe_array[pdn->pe_number];
> -		if (!pe->table_group.group)
> +		pe = pnv_ioda_get_pe(pdev);
> +		if (!pe || !pe->table_group.group)
>  			return 0;
> +
>  		iommu_add_device(&pe->table_group, dev);
>  		return 0;
>  	case BUS_NOTIFY_DEL_DEVICE:
> 

-- 
Alexey