On Mon, Apr 09, 2007 at 02:55:54PM -0700, Ashok Raj wrote:
> +/*
> + * find the upstream PCIE-to-PCI bridge of a PCI device
> + * if the device is PCIE, return NULL
> + * if the device isn't connected to a PCIE bridge (that is its parent is a
> + * legacy PCI bridge and the bridge is directly connected to bus 0), return 
> its
> + * parent
> + */
> +struct pci_dev *
> +pci_find_upstream_pcie_bridge(struct pci_dev *pdev)
> +{
> +     struct pci_dev *tmp = NULL;
> +
> +     if (pdev->is_pcie)
> +             return NULL;
> +     while (1) {
> +             if (!pdev->bus->self)
> +                     break;
> +             pdev = pdev->bus->self;
> +             /* a p2p bridge */
> +             if (!pdev->is_pcie) {
> +                     tmp = pdev;
> +                     continue;
> +             }
> +             /* PCI device should connect to a PCIE bridge */
> +             BUG_ON(pdev->pcie_type != PCI_EXP_TYPE_PCI_BRIDGE);
> +             return pdev;
> +     }
> +
> +     return tmp;
> +}

No locking while you walk up the bus list?

> --- linux-2.6.21-rc5.orig/include/linux/pci.h 2007-04-03 04:30:51.000000000 
> -0700
> +++ linux-2.6.21-rc5/include/linux/pci.h      2007-04-03 06:58:58.000000000 
> -0700
> @@ -126,6 +126,7 @@
>       unsigned short  subsystem_device;
>       unsigned int    class;          /* 3 bytes: (base,sub,prog-if) */
>       u8              hdr_type;       /* PCI header type (`multi' flag masked 
> out) */
> +     u8              pcie_type;      /* PCI-E device/port type */
>       u8              rom_base_reg;   /* which config register controls the 
> ROM */
>       u8              pin;            /* which interrupt pin this device uses 
> */
>  
> @@ -168,6 +169,7 @@
>       unsigned int    msi_enabled:1;
>       unsigned int    msix_enabled:1;
>       unsigned int    is_managed:1;
> +     unsigned int    is_pcie:1;

Do you really need both fields?  Wouldn't just the pcie_type one work
(with some NOT_PCIE type being set for it if it isn't I suppose.)

thanks,

greg k-h
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