Re: [Qemu-devel] [PATCH v2 02/12] vfio/pci: Pass an error object to vfio_populate_device

[Markus Armbruster <armbru@redhat.com>]

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

> Pass an error object to prepare for migration to VFIO-PCI realize.
> The returned value will be removed later on.
>
> The case where error recovery cannot be enabled is not converted into
> an error object but directly reported through error_report, as before.
> Populating an error instead would cause the future realize function to
> fail, which is not wanted.
>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>
> ---
>
> v1 -> v2:
> - this patch now comes before the actual realize migration
> - do not handle the error recovery issue as an error
> ---
>  hw/vfio/pci.c | 26 +++++++++++++-------------
>  1 file changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index ca0293d..9fe970a 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -2199,7 +2199,7 @@ int vfio_populate_vga(VFIOPCIDevice *vdev)
>      return 0;
>  }
>  
> -static int vfio_populate_device(VFIOPCIDevice *vdev)
> +static int vfio_populate_device(VFIOPCIDevice *vdev, Error **errp)
>  {
>      VFIODevice *vbasedev = &vdev->vbasedev;
>      struct vfio_region_info *reg_info;
> @@ -2208,18 +2208,18 @@ static int vfio_populate_device(VFIOPCIDevice *vdev)
>  
>      /* Sanity check device */
>      if (!(vbasedev->flags & VFIO_DEVICE_FLAGS_PCI)) {
> -        error_report("vfio: Um, this isn't a PCI device");
> +        error_setg(errp, "this isn't a PCI device");
>          goto error;
>      }
>  
>      if (vbasedev->num_regions < VFIO_PCI_CONFIG_REGION_INDEX + 1) {
> -        error_report("vfio: unexpected number of io regions %u",
> -                     vbasedev->num_regions);
> +        error_setg(errp, "unexpected number of io regions %u",
> +                   vbasedev->num_regions);
>          goto error;
>      }
>  
>      if (vbasedev->num_irqs < VFIO_PCI_MSIX_IRQ_INDEX + 1) {
> -        error_report("vfio: unexpected number of irqs %u", vbasedev->num_irqs);
> +        error_setg(errp, "unexpected number of irqs %u", vbasedev->num_irqs);
>          goto error;
>      }
>  
> @@ -2231,7 +2231,7 @@ static int vfio_populate_device(VFIOPCIDevice *vdev)
>          g_free(name);
>  
>          if (ret) {
> -            error_report("vfio: Error getting region %d info: %m", i);
> +            error_setg_errno(errp, -ret, "failed to get region %d info", i);
>              goto error;
>          }
>  
> @@ -2241,7 +2241,7 @@ static int vfio_populate_device(VFIOPCIDevice *vdev)
>      ret = vfio_get_region_info(vbasedev,
>                                 VFIO_PCI_CONFIG_REGION_INDEX, &reg_info);
>      if (ret) {
> -        error_report("vfio: Error getting config info: %m");
> +        error_setg_errno(errp, -ret, "failed to get config info");
>          goto error;
>      }
>  
> @@ -2261,8 +2261,8 @@ static int vfio_populate_device(VFIOPCIDevice *vdev)
>      if (vdev->features & VFIO_FEATURE_ENABLE_VGA) {
>          ret = vfio_populate_vga(vdev);
>          if (ret) {
> -            error_report(
> -                "vfio: Device does not support requested feature x-vga");
> +            error_setg_errno(errp, -ret,
> +                "device does not support requested feature x-vga");
>              goto error;
>          }
>      }

What about the error_report() in vfio_populate_vga()?  Should the
vfio_populate_vga() take an Error * argument?

> @@ -2277,7 +2277,7 @@ static int vfio_populate_device(VFIOPCIDevice *vdev)
>      } else if (irq_info.count == 1) {
>          vdev->pci_aer = true;
>      } else {
> -        error_report("vfio: %s "
> +        error_report(WARN_PREFIX
>                       "Could not enable error recovery for the device",
>                       vbasedev->name);
>      }
> @@ -2561,9 +2561,9 @@ static int vfio_initfn(PCIDevice *pdev)
>          goto error;
>      }
>  
> -    ret = vfio_populate_device(vdev);
> -    if (ret) {
> -        return ret;
> +    ret = vfio_populate_device(vdev, &err);
> +    if (err) {
> +        goto error;
>      }
>  
>      /* Get a copy of config space */