[PATCH V4 01/14] notify: pass error to notifier with return

[Steve Sistare <steven.sistare@oracle.com>]

Pass an error object as the third parameter to "notifier with return"
notifiers, so clients no longer need to bundle an error object in the
opaque data.  The new parameter is used in a later patch.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
---
 hw/virtio/vhost-user.c     | 2 +-
 hw/virtio/virtio-balloon.c | 3 ++-
 include/qemu/notify.h      | 7 +++++--
 migration/postcopy-ram.c   | 2 +-
 migration/ram.c            | 2 +-
 util/notify.c              | 5 +++--
 6 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index f214df8..f502345 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -2084,7 +2084,7 @@ static int vhost_user_postcopy_end(struct vhost_dev *dev, Error **errp)
 }
 
 static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier,
-                                        void *opaque)
+                                        void *opaque, Error **errp)
 {
     struct PostcopyNotifyData *pnd = opaque;
     struct vhost_user *u = container_of(notifier, struct vhost_user,
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index 486fe3d..89f853f 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -633,7 +633,8 @@ static void virtio_balloon_free_page_done(VirtIOBalloon *s)
 }
 
 static int
-virtio_balloon_free_page_hint_notify(NotifierWithReturn *n, void *data)
+virtio_balloon_free_page_hint_notify(NotifierWithReturn *n, void *data,
+                                     Error **errp)
 {
     VirtIOBalloon *dev = container_of(n, VirtIOBalloon, free_page_hint_notify);
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
diff --git a/include/qemu/notify.h b/include/qemu/notify.h
index bcfa70f..9a85631 100644
--- a/include/qemu/notify.h
+++ b/include/qemu/notify.h
@@ -45,12 +45,15 @@ bool notifier_list_empty(NotifierList *list);
 /* Same as Notifier but allows .notify() to return errors */
 typedef struct NotifierWithReturn NotifierWithReturn;
 
+typedef int (*NotifierWithReturnFunc)(NotifierWithReturn *notifier, void *data,
+                                      Error **errp);
+
 struct NotifierWithReturn {
     /**
      * Return 0 on success (next notifier will be invoked), otherwise
      * notifier_with_return_list_notify() will stop and return the value.
      */
-    int (*notify)(NotifierWithReturn *notifier, void *data);
+    NotifierWithReturnFunc notify;
     QLIST_ENTRY(NotifierWithReturn) node;
 };
 
@@ -69,6 +72,6 @@ void notifier_with_return_list_add(NotifierWithReturnList *list,
 void notifier_with_return_remove(NotifierWithReturn *notifier);
 
 int notifier_with_return_list_notify(NotifierWithReturnList *list,
-                                     void *data);
+                                     void *data, Error **errp);
 
 #endif
diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 893ec8f..3ab2f6b 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -80,7 +80,7 @@ int postcopy_notify(enum PostcopyNotifyReason reason, Error **errp)
     pnd.errp = errp;
 
     return notifier_with_return_list_notify(&postcopy_notifier_list,
-                                            &pnd);
+                                            &pnd, errp);
 }
 
 /*
diff --git a/migration/ram.c b/migration/ram.c
index 4649a81..5b6b09e 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -428,7 +428,7 @@ int precopy_notify(PrecopyNotifyReason reason, Error **errp)
     pnd.reason = reason;
     pnd.errp = errp;
 
-    return notifier_with_return_list_notify(&precopy_notifier_list, &pnd);
+    return notifier_with_return_list_notify(&precopy_notifier_list, &pnd, errp);
 }
 
 uint64_t ram_bytes_remaining(void)
diff --git a/util/notify.c b/util/notify.c
index 76bab21..c6e158f 100644
--- a/util/notify.c
+++ b/util/notify.c
@@ -61,13 +61,14 @@ void notifier_with_return_remove(NotifierWithReturn *notifier)
     QLIST_REMOVE(notifier, node);
 }
 
-int notifier_with_return_list_notify(NotifierWithReturnList *list, void *data)
+int notifier_with_return_list_notify(NotifierWithReturnList *list, void *data,
+                                     Error **errp)
 {
     NotifierWithReturn *notifier, *next;
     int ret = 0;
 
     QLIST_FOREACH_SAFE(notifier, &list->notifiers, node, next) {
-        ret = notifier->notify(notifier, data);
+        ret = notifier->notify(notifier, data, errp);
         if (ret != 0) {
             break;
         }
-- 
1.8.3.1