Re: [Qemu-devel] [PATCH v4 16/17] vfio/pci: Remove vfio_populate_device returned value

[Markus Armbruster <armbru@redhat.com>]

Eric Auger <eric.auger@redhat.com> writes:

> The returned value (either -errno or -1) is not used anymore by the caller,
> vfio_realize, since the error now is stored in the error object. So let's
> remove it.
>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
>  hw/vfio/pci.c | 23 ++++++++++-------------
>  1 file changed, 10 insertions(+), 13 deletions(-)
>
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index cea4d48..eb08d01 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -2223,7 +2223,7 @@ int vfio_populate_vga(VFIOPCIDevice *vdev, Error **errp)
>      return 0;
>  }
>  
> -static int vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
> +static void vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
>  {
>      VFIODevice *vbasedev = &vdev->vbasedev;
>      struct vfio_region_info *reg_info;
> @@ -2233,18 +2233,18 @@ static int vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
>      /* Sanity check device */
>      if (!(vbasedev->flags & VFIO_DEVICE_FLAGS_PCI)) {
>          error_setg(errp, "this isn't a PCI device");
> -        goto error;
> +        return;
>      }
>  
>      if (vbasedev->num_regions < VFIO_PCI_CONFIG_REGION_INDEX + 1) {
>          error_setg(errp, "unexpected number of io regions %u",
>                     vbasedev->num_regions);
> -        goto error;
> +        return;
>      }
>  
>      if (vbasedev->num_irqs < VFIO_PCI_MSIX_IRQ_INDEX + 1) {
>          error_setg(errp, "unexpected number of irqs %u", vbasedev->num_irqs);
> -        goto error;
> +        return;
>      }
>  
>      for (i = VFIO_PCI_BAR0_REGION_INDEX; i < VFIO_PCI_ROM_REGION_INDEX; i++) {
> @@ -2256,7 +2256,7 @@ static int vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
>  
>          if (ret) {
>              error_setg_errno(errp, -ret, "failed to get region %d info", i);
> -            goto error;
> +            return;
>          }
>  
>          QLIST_INIT(&vdev->bars[i].quirks);
> @@ -2266,7 +2266,7 @@ static int vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
>                                 VFIO_PCI_CONFIG_REGION_INDEX, &reg_info);
>      if (ret) {
>          error_setg_errno(errp, -ret, "failed to get config info");
> -        goto error;
> +        return;
>      }
>  
>      trace_vfio_populate_device_config(vdev->vbasedev.name,
> @@ -2287,7 +2287,7 @@ static int vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
>          if (ret) {
>              error_append_hint(errp, "device does not support "
>                                "requested feature x-vga\n");
> -            goto error;
> +            return;
>          }
>      }
>  
> @@ -2297,7 +2297,6 @@ static int vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
>      if (ret) {
>          /* This can fail for an old kernel or legacy PCI dev */
>          trace_vfio_populate_device_get_irq_info_failure();
> -        ret = 0;
>      } else if (irq_info.count == 1) {
>          vdev->pci_aer = true;
>      } else {
> @@ -2305,9 +2304,6 @@ static int vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
>                       "Could not enable error recovery for the device",
>                       vbasedev->name);
>      }
> -
> -error:
> -    return ret;
>  }
>  
>  static void vfio_put_device(VFIOPCIDevice *vdev)
> @@ -2579,8 +2575,9 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
>          goto error;
>      }
>  
> -    ret = vfio_populate_device(vdev, errp);
> -    if (ret) {
> +    vfio_populate_device(vdev, &err);
> +    if (err) {
> +        error_propagate(errp, err);
>          goto error;
>      }

PATCH 03 checks err, PATCH 14 flips to ret, and this one flips back.
Have you considered dropping both flips?  Your choice.