virtio-mem: Use -ETXTBSY as error code if the device is busy

Let's be able to distinguish if the device or if memory is busy.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-15-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index a719e1a..abd93b7 100644 (file)
--- a/drivers/virtio/virtio_mem.c
+++ b/drivers/virtio/virtio_mem.c
@@ -893,7 +893,7 @@ static int virtio_mem_send_plug_request(struct virtio_mem *vm, uint64_t addr,
        case VIRTIO_MEM_RESP_NACK:
                return -EAGAIN;
        case VIRTIO_MEM_RESP_BUSY:
-               return -EBUSY;
+               return -ETXTBSY;
        case VIRTIO_MEM_RESP_ERROR:
                return -EINVAL;
        default:
@@ -919,7 +919,7 @@ static int virtio_mem_send_unplug_request(struct virtio_mem *vm, uint64_t addr,
                vm->plugged_size -= size;
                return 0;
        case VIRTIO_MEM_RESP_BUSY:
-               return -EBUSY;
+               return -ETXTBSY;
        case VIRTIO_MEM_RESP_ERROR:
                return -EINVAL;
        default:
@@ -941,7 +941,7 @@ static int virtio_mem_send_unplug_all_request(struct virtio_mem *vm)
                atomic_set(&vm->config_changed, 1);
                return 0;
        case VIRTIO_MEM_RESP_BUSY:
-               return -EBUSY;
+               return -ETXTBSY;
        default:
                return -ENOMEM;
        }
@@ -1557,11 +1557,15 @@ retry:
                 * or we have too many offline memory blocks.
                 */
                break;
-       case -EBUSY:
+       case -ETXTBSY:
                /*
                 * The hypervisor cannot process our request right now
-                * (e.g., out of memory, migrating) or we cannot free up
-                * any memory to unplug it (all plugged memory is busy).
+                * (e.g., out of memory, migrating);
+                */
+       case -EBUSY:
+               /*
+                * We cannot free up any memory to unplug it (all plugged memory
+                * is busy).
                 */
        case -ENOMEM:
                /* Out of memory, try again later. */