On Thursday, March 5, 2020 11:29:32 AM -03 David Hildenbrand wrote:
> Everybody discards the error. Let's error_report() instead so this error
> doesn't get lost.
>
> This is now the same error handling as in qemu_vfio_do_mapping(). However,
> we don't report any errors via the return value to the caller. This seems
> to be one of these "will never happen, but let's better print an error
> because the caller can't handle it either way" cases.
>
> Cc: Richard Henderson <rth@twiddle.net>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Eduardo Habkost <ehabkost@redhat.com>
> Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
> Cc: Alex Williamson <alex.williamson@redhat.com>
> Cc: Stefan Hajnoczi <stefanha@redhat.com>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
Acked-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
> util/vfio-helpers.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
> index f31aa77ffe..7085ca702c 100644
> --- a/util/vfio-helpers.c
> +++ b/util/vfio-helpers.c
> @@ -541,8 +541,7 @@ static int qemu_vfio_do_mapping(QEMUVFIOState *s, void
> *host, size_t size, /**
> * Undo the DMA mapping from @s with VFIO, and remove from mapping list.
> */
> -static void qemu_vfio_undo_mapping(QEMUVFIOState *s, IOVAMapping *mapping,
> - Error **errp)
> +static void qemu_vfio_undo_mapping(QEMUVFIOState *s, IOVAMapping *mapping)
> {
> int index;
> struct vfio_iommu_type1_dma_unmap unmap = {
> @@ -557,7 +556,7 @@ 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_errno(errp, errno, "VFIO_UNMAP_DMA failed");
> + error_report("VFIO_UNMAP_DMA failed: %s", strerror(errno));
> }
> memmove(mapping, &s->mappings[index + 1],
> sizeof(s->mappings[0]) * (s->nr_mappings - index - 1));
> @@ -622,7 +621,7 @@ int qemu_vfio_dma_map(QEMUVFIOState *s, void *host,
> size_t size, assert(qemu_vfio_verify_mappings(s));
> ret = qemu_vfio_do_mapping(s, host, size, iova0);
> if (ret) {
> - qemu_vfio_undo_mapping(s, mapping, NULL);
> + qemu_vfio_undo_mapping(s, mapping);
> goto out;
> }
> s->low_water_mark += size;
> @@ -682,7 +681,7 @@ void qemu_vfio_dma_unmap(QEMUVFIOState *s, void *host)
> if (!m) {
> goto out;
> }
> - qemu_vfio_undo_mapping(s, m, NULL);
> + qemu_vfio_undo_mapping(s, m);
> out:
> qemu_mutex_unlock(&s->lock);
> }
> @@ -699,7 +698,7 @@ void qemu_vfio_close(QEMUVFIOState *s)
> return;
> }
> while (s->nr_mappings) {
> - qemu_vfio_undo_mapping(s, &s->mappings[s->nr_mappings - 1], NULL);
> + qemu_vfio_undo_mapping(s, &s->mappings[s->nr_mappings - 1]);
> }
> ram_block_notifier_remove(&s->ram_notifier);
> qemu_vfio_reset(s);
--
Murilo