Re: [dpdk-dev] [PATCH] bus/pci: nvme on Windows requires class id and bus

[Tal Shnaiderman <talshn@nvidia.com>]

> Subject: [PATCH] bus/pci: nvme on Windows requires class id and bus
> 
> External email: Use caution opening links or attachments
> 
> 
> Attaching to an NVMe disk on Windows using SPDK requires the PCI class ID
> and device.bus fields. Decode the class ID from the PCI device info strings if it
> is present and set device.bus.
> 
> Signed-off-by: Nick Connolly <nick.connolly@mayadata.io>
> ---
>  drivers/bus/pci/windows/pci.c | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/bus/pci/windows/pci.c b/drivers/bus/pci/windows/pci.c
> index f66258452..3d11444c2 100644
> --- a/drivers/bus/pci/windows/pci.c
> +++ b/drivers/bus/pci/windows/pci.c
> @@ -280,17 +280,24 @@ parse_pci_hardware_id(const char *buf, struct
> rte_pci_id *pci_id)  {
>         int ids = 0;
>         uint16_t vendor_id, device_id;
> -       uint32_t subvendor_id = 0;
> +       uint32_t subvendor_id = 0, class_id = 0;
> +       const char *cp;
> 
>         ids = sscanf_s(buf, "PCI\\VEN_%" PRIx16 "&DEV_%" PRIx16
> "&SUBSYS_%"
>                 PRIx32, &vendor_id, &device_id, &subvendor_id);
>         if (ids != 3)
>                 return -1;
> 
> +       /* Try and find PCI class ID */
> +       for (cp = buf; !(cp[0] == 0 && cp[1] == 0); cp++)

How about 
for (cp = buf; cp[0] || cp[1]; cp++)

> +               if (*cp == '&' && sscanf_s(cp, "&CC_%" PRIx32, &class_id) == 1)

Could there be a case where PCI\\VEN_v(4)&DEV_d(4)&CC_c(2)s(2) exist but PCI\\VEN_v(4)&DEV_d(4)&CC_c(2)s(2)p(2) doesn't? In that case the parsing would be incorrect.

> +                       break;
> +
>         pci_id->vendor_id = vendor_id;
>         pci_id->device_id = device_id;
>         pci_id->subsystem_device_id = subvendor_id >> 16;
>         pci_id->subsystem_vendor_id = subvendor_id & 0xffff;
> +       pci_id->class_id = class_id;
>         return 0;
>  }
> 
> @@ -339,6 +346,7 @@ pci_scan_one(HDEVINFO dev_info,
> PSP_DEVINFO_DATA device_info_data)
>         if (ret != 0)
>                 goto end;
> 
> +       dev->device.bus = &rte_pci_bus.bus;
>         dev->addr = addr;
>         dev->id = pci_id;
>         dev->max_vfs = 0; /* TODO: get max_vfs */
> --
> 2.25.1