exec/memory: Add symbol for memory listener priority for device backend

Add MEMORY_LISTENER_PRIORITY_DEV_BACKEND for the symbolic value
for memory listener to replace the hard-coded value 10 for the
device backend.

No functional change intended.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <8314d91688030d7004e96958f12e2c83fb889245.1687279702.git.isaku.yamahata@intel.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

accel/kvm/kvm-all.c

@@ -1802,7 +1802,7 @@ static MemoryListener kvm_io_listener = {
     .name = "kvm-io",
     .eventfd_add = kvm_io_ioeventfd_add,
     .eventfd_del = kvm_io_ioeventfd_del,
-    .priority = 10,
+    .priority = MEMORY_LISTENER_PRIORITY_DEV_BACKEND,
 };
 
 int kvm_set_irq(KVMState *s, int irq, int level)

hw/remote/proxy-memory-listener.c

@@ -217,7 +217,7 @@ void proxy_memory_listener_configure(ProxyMemoryListener *proxy_listener,
     proxy_listener->listener.commit = proxy_memory_listener_commit;
     proxy_listener->listener.region_add = proxy_memory_listener_region_addnop;
     proxy_listener->listener.region_nop = proxy_memory_listener_region_addnop;
-    proxy_listener->listener.priority = 10;
+    proxy_listener->listener.priority = MEMORY_LISTENER_PRIORITY_DEV_BACKEND;
     proxy_listener->listener.name = "proxy";
 
     memory_listener_register(&proxy_listener->listener,

hw/virtio/vhost.c

@@ -1444,7 +1444,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
         .log_sync = vhost_log_sync,
         .log_global_start = vhost_log_global_start,
         .log_global_stop = vhost_log_global_stop,
-        .priority = 10
+        .priority = MEMORY_LISTENER_PRIORITY_DEV_BACKEND
     };
 
     hdev->iommu_listener = (MemoryListener) {

include/exec/memory.h

@@ -812,6 +812,7 @@ struct IOMMUMemoryRegion {
     QLIST_FOREACH((n), &(mr)->iommu_notify, node)
 
 #define MEMORY_LISTENER_PRIORITY_ACCEL          10
+#define MEMORY_LISTENER_PRIORITY_DEV_BACKEND    10
 
 /**
  * struct MemoryListener: callbacks structure for updates to the physical memory map