Re: [PATCH v5] bus/pci: fix legacy device IO port map in secondary process

["Gupta, Nipun" <nipun.gupta@amd.com>]

On 10/24/2023 7:30 AM, Wenwu Ma wrote:
> When doing IO port mapping for legacy device in secondary process, the
> region information is missing, so, we need to refill it.
> 
> Fixes: 4b741542ecde ("bus/pci: avoid depending on private kernel value")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Wenwu Ma <wenwux.ma@intel.com>
> ---
> v5:
>   - adding checks to vfio setup
> v4:
>   - adjusting commit log
> v3:
>   - adjusting variable settings
> v2:
>   - add release of device in pci_vfio_ioport_unmap
> 
> ---
>   drivers/bus/pci/linux/pci_vfio.c | 52 ++++++++++++++++++++++++++++++--
>   1 file changed, 50 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/bus/pci/linux/pci_vfio.c b/drivers/bus/pci/linux/pci_vfio.c
> index 3f3201daf2..a1f7cc2421 100644
> --- a/drivers/bus/pci/linux/pci_vfio.c
> +++ b/drivers/bus/pci/linux/pci_vfio.c
> @@ -1230,6 +1230,36 @@ pci_vfio_ioport_map(struct rte_pci_device *dev, int bar,
>   		return -1;
>   	}
>   
> +	if (rte_eal_process_type() == RTE_PROC_SECONDARY) {
> +		struct vfio_device_info device_info = { .argsz = sizeof(device_info) };
> +		char pci_addr[PATH_MAX];
> +		int vfio_dev_fd;
> +		struct rte_pci_addr *loc = &dev->addr;
> +		/* store PCI address string */
> +		snprintf(pci_addr, sizeof(pci_addr), PCI_PRI_FMT,
> +				loc->domain, loc->bus, loc->devid, loc->function);
> +
> +		vfio_dev_fd = rte_intr_dev_fd_get(dev->intr_handle);
> +		if (vfio_dev_fd < 0)
> +			return -1;
> +
> +		if (vfio_dev_fd == 0) {
> +			if (rte_vfio_setup_device(rte_pci_get_sysfs_path(), pci_addr,
> +					&vfio_dev_fd, &device_info))
> +				return -1;
> +
> +			/* we need save vfio_dev_fd, so it can be used during release */
> +			if (rte_intr_dev_fd_set(dev->intr_handle, vfio_dev_fd))
> +				return -1;
> +		} else {
> +			if (ioctl(vfio_dev_fd, VFIO_DEVICE_GET_INFO, &device_info))
> +				return -1;
> +		}

Code upto here is to get device info, IMO we should have a separate API 
for this in VFIO layer which can be used from any driver, rather than 
being limited here.

This can go into a new API like rte_vfio_get_device_info() in eal_vfio.c.

Thanks,
Nipun