Report stringified errno in VFIO related errors

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: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Message-Id: <4949c3ecf1a32189b8a4b5eb4b0fd04c1122501d.1581674006.git.mprivozn@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

1 files changed, 3 insertions, 3 deletions

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;
     }