diff mbox series

[9/9] block/nvme: Only report VFIO error on failed retry

Message ID 20210824141142.1165291-10-philmd@redhat.com
State New
Headers show
Series block/nvme: Rework error reporting | expand

Commit Message

Philippe Mathieu-Daudé Aug. 24, 2021, 2:11 p.m. UTC 
We expect the first qemu_vfio_dma_map() to fail (indicating
DMA mappings exhaustion, see commit 15a730e7a3a). Do not
report the first failure as error, since we are going to
flush the mappings and retry.

This removes spurious error message displayed on the monitor:

  (qemu) c
  (qemu) qemu-kvm: VFIO_MAP_DMA failed: No space left on device
  (qemu) info status
  VM status: running

Reported-by: Tingting Mao <timao@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

Klaus Jensen Aug. 25, 2021, 12:18 p.m. UTC | #1 
On Aug 24 16:11, Philippe Mathieu-Daudé wrote:
> We expect the first qemu_vfio_dma_map() to fail (indicating
> DMA mappings exhaustion, see commit 15a730e7a3a). Do not
> report the first failure as error, since we are going to
> flush the mappings and retry.
> 
> This removes spurious error message displayed on the monitor:
> 
>   (qemu) c
>   (qemu) qemu-kvm: VFIO_MAP_DMA failed: No space left on device
>   (qemu) info status
>   VM status: running
> 
> Reported-by: Tingting Mao <timao@redhat.com>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Neat.

Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
diff mbox series

Patch

diff --git a/block/nvme.c b/block/nvme.c
index 80546b0babd..abfe305baf2 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -1019,6 +1019,7 @@  static coroutine_fn int nvme_cmd_map_qiov(BlockDriverState *bs, NvmeCmd *cmd,
     uint64_t *pagelist = req->prp_list_page;
     int i, j, r;
     int entries = 0;
+    Error *local_err = NULL, **errp = NULL;
 
     assert(qiov->size);
     assert(QEMU_IS_ALIGNED(qiov->size, s->page_size));
@@ -1031,7 +1032,7 @@  static coroutine_fn int nvme_cmd_map_qiov(BlockDriverState *bs, NvmeCmd *cmd,
 try_map:
         r = qemu_vfio_dma_map(s->vfio,
                               qiov->iov[i].iov_base,
-                              len, true, &iova, NULL);
+                              len, true, &iova, errp);
         if (r == -ENOSPC) {
             /*
              * In addition to the -ENOMEM error, the VFIO_IOMMU_MAP_DMA
@@ -1066,6 +1067,8 @@  try_map:
                     goto fail;
                 }
             }
+            errp = &local_err;
+
             goto try_map;
         }
         if (r) {
@@ -1109,6 +1112,9 @@  fail:
      * because they are already mapped before calling this function; for
      * temporary mappings, a later nvme_cmd_(un)map_qiov will reclaim by
      * calling qemu_vfio_dma_reset_temporary when necessary. */
+    if (local_err) {
+        error_reportf_err(local_err, "Cannot map buffer for DMA: ");
+    }
     return r;
 }