Re: [PATCH v2] Report stringified errno in VFIO related errors

[Auger Eric <eric.auger@redhat.com>]

Hi Michal,

On 2/14/20 10:55 AM, Michal Privoznik wrote:
> In a few places we report errno formatted as a negative integer.
> This is not as user friendly as it can be. Use strerror() and/or
> error_setg_errno() instead.
> 
> Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric
> ---
> 
> v1 posted here:
> 
> https://lists.nongnu.org/archive/html/qemu-devel/2020-02/msg03623.html
> 
> diff to v1:
>  - Change error reporting in vfio_dma_unmap() too as I missed it in v1.
> 
>  hw/vfio/common.c    | 4 ++--
>  util/vfio-helpers.c | 6 +++---
>  2 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
> index 5ca11488d6..0b3593b3c0 100644
> --- a/hw/vfio/common.c
> +++ b/hw/vfio/common.c
> @@ -319,7 +319,7 @@ static int vfio_dma_unmap(VFIOContainer *container,
>              unmap.size -= 1ULL << ctz64(container->pgsizes);
>              continue;
>          }
> -        error_report("VFIO_UNMAP_DMA: %d", -errno);
> +        error_report("VFIO_UNMAP_DMA failed: %s", strerror(errno));
>          return -errno;
>      }
>  
> @@ -352,7 +352,7 @@ static int vfio_dma_map(VFIOContainer *container, hwaddr iova,
>          return 0;
>      }
>  
> -    error_report("VFIO_MAP_DMA: %d", -errno);
> +    error_report("VFIO_MAP_DMA failed: %s", strerror(errno));
>      return -errno;
>  }
>  
> diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
> index 813f7ec564..ddd9a96e76 100644
> --- a/util/vfio-helpers.c
> +++ b/util/vfio-helpers.c
> @@ -545,7 +545,7 @@ static int qemu_vfio_do_mapping(QEMUVFIOState *s, void *host, size_t size,
>      trace_qemu_vfio_do_mapping(s, host, size, iova);
>  
>      if (ioctl(s->container, VFIO_IOMMU_MAP_DMA, &dma_map)) {
> -        error_report("VFIO_MAP_DMA: %d", -errno);
> +        error_report("VFIO_MAP_DMA failed: %s", strerror(errno));
>          return -errno;
>      }
>      return 0;
> @@ -570,7 +570,7 @@ static void qemu_vfio_undo_mapping(QEMUVFIOState *s, IOVAMapping *mapping,
>      assert(QEMU_IS_ALIGNED(mapping->size, qemu_real_host_page_size));
>      assert(index >= 0 && index < s->nr_mappings);
>      if (ioctl(s->container, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
> -        error_setg(errp, "VFIO_UNMAP_DMA failed: %d", -errno);
> +        error_setg_errno(errp, errno, "VFIO_UNMAP_DMA failed");
>      }
>      memmove(mapping, &s->mappings[index + 1],
>              sizeof(s->mappings[0]) * (s->nr_mappings - index - 1));
> @@ -669,7 +669,7 @@ int qemu_vfio_dma_reset_temporary(QEMUVFIOState *s)
>      trace_qemu_vfio_dma_reset_temporary(s);
>      qemu_mutex_lock(&s->lock);
>      if (ioctl(s->container, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
> -        error_report("VFIO_UNMAP_DMA: %d", -errno);
> +        error_report("VFIO_UNMAP_DMA failed: %s", strerror(errno));
>          qemu_mutex_unlock(&s->lock);
>          return -errno;
>      }
>