devlink: introduce __devl_is_registered() helper and use it instead of xa_get_mark()

Introduce __devl_is_registered() which does not assert on devlink
instance lock and use it in notifications which may be called
without devlink instance lock held.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net/devlink/devl_internal.h

@@ -91,10 +91,15 @@ extern struct genl_family devlink_nl_family;
 
 struct devlink *devlinks_xa_find_get(struct net *net, unsigned long *indexp);
 
+static inline bool __devl_is_registered(struct devlink *devlink)
+{
+	return xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
+}
+
 static inline bool devl_is_registered(struct devlink *devlink)
 {
 	devl_assert_locked(devlink);
-	return xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
+	return __devl_is_registered(devlink);
 }
 
 static inline void devl_dev_lock(struct devlink *devlink, bool dev_lock)

net/devlink/linecard.c

@@ -136,7 +136,7 @@ static void devlink_linecard_notify(struct devlink_linecard *linecard,
 	WARN_ON(cmd != DEVLINK_CMD_LINECARD_NEW &&
 		cmd != DEVLINK_CMD_LINECARD_DEL);
 
-	if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
+	if (!__devl_is_registered(devlink))
 		return;
 
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);

net/devlink/port.c

@@ -512,7 +512,7 @@ static void devlink_port_notify(struct devlink_port *devlink_port,
 
 	WARN_ON(cmd != DEVLINK_CMD_PORT_NEW && cmd != DEVLINK_CMD_PORT_DEL);
 
-	if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
+	if (!__devl_is_registered(devlink))
 		return;
 
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);

net/devlink/region.c

@@ -234,7 +234,8 @@ static void devlink_nl_region_notify(struct devlink_region *region,
 	struct sk_buff *msg;
 
 	WARN_ON(cmd != DEVLINK_CMD_REGION_NEW && cmd != DEVLINK_CMD_REGION_DEL);
-	if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
+
+	if (!__devl_is_registered(devlink))
 		return;
 
 	msg = devlink_nl_region_notify_build(region, snapshot, cmd, 0, 0);