[PATCH v2 6/9] vfio: Remove reports of DMA mapping errors in backends

[Cédric Le Goater]

Currently, the IOMMU backend, VFIO IOMMU Type 1 aka. legacy and
IOMMUFD, mapping handlers return an errno and also report an error.
This can produce a lot of output at runtime for recurring DMA mapping
errors and is redundant with the errors reported by the callers in
vfio_container_dma_un/map() routines.

Simply remove to let the callers handle the error. The mapping handler
of the IOMMUFD backend has a comment suggesting MMIO region mapping
failures return EFAULT. I am not sure this is entirely true, so keep
the EFAULT case until the conditions are clarified.

Signed-off-by: Cédric Le Goater <c...@redhat.com>
---
 backends/iommufd.c  | 3 ---
 hw/vfio/container.c | 2 --
 2 files changed, 5 deletions(-)

diff --git a/backends/iommufd.c b/backends/iommufd.c
index 
7b4fc8ec460ef635b9ed5ac7b201f124476b512a..d57da44755be3d7fdba74f7dbecfe6d1c89921ba
 100644
--- a/backends/iommufd.c
+++ b/backends/iommufd.c
@@ -167,8 +167,6 @@ int iommufd_backend_map_dma(IOMMUFDBackend *be, uint32_t 
ioas_id, hwaddr iova,
         /* TODO: Not support mapping hardware PCI BAR region for now. */
         if (errno == EFAULT) {
             warn_report("IOMMU_IOAS_MAP failed: %m, PCI BAR?");
-        } else {
-            error_report("IOMMU_IOAS_MAP failed: %m");
         }
     }
     return ret;
@@ -203,7 +201,6 @@ int iommufd_backend_unmap_dma(IOMMUFDBackend *be, uint32_t 
ioas_id,
 
     if (ret) {
         ret = -errno;
-        error_report("IOMMU_IOAS_UNMAP failed: %m");
     }
     return ret;
 }
diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index 
4ebb5268088d0a2006e0ed04afec0ee746ed2c1d..7c57bdd27b72731db5cf4f9446d954e143b4747e
 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -159,7 +159,6 @@ static int vfio_legacy_dma_unmap(const VFIOContainerBase 
*bcontainer,
             unmap.size -= 1ULL << ctz64(bcontainer->pgsizes);
             continue;
         }
-        error_report("VFIO_UNMAP_DMA failed: %s", strerror(errno));
         return -errno;
     }
 
@@ -204,7 +203,6 @@ static int vfio_legacy_dma_map(const VFIOContainerBase 
*bcontainer, hwaddr iova,
         return 0;
     }
 
-    error_report("VFIO_MAP_DMA failed: %s", strerror(errno));
     return -errno;
 }
 
-- 
2.48.1