[PATCH net-next v5 3/4] net: devlink: make the devlink_ops::info_get() callback optional

[Vincent Mailhol]

Some drivers only reported the driver name in their
devlink_ops::info_get() callback. Now that the core provides this
information, the callback became empty. For such drivers, just
removing the callback would prevent the core from executing
devlink_nl_info_fill() meaning that "devlink dev info" would not
return anything.

Make the callback function optional by executing
devlink_nl_info_fill() even if devlink_ops::info_get() is NULL.

N.B.: the drivers with devlink support which previously did not
implement devlink_ops::info_get() will now also be able to report
the driver name.

Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
---
 net/core/devlink.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 3babc16eeb6b..817d978bb729 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -6773,9 +6773,11 @@ devlink_nl_info_fill(struct sk_buff *msg, struct devlink *devlink,
 		goto err_cancel_msg;
 
 	req.msg = msg;
-	err = devlink->ops->info_get(devlink, &req, extack);
-	if (err)
-		goto err_cancel_msg;
+	if (devlink->ops->info_get) {
+		err = devlink->ops->info_get(devlink, &req, extack);
+		if (err)
+			goto err_cancel_msg;
+	}
 
 	err = devlink_nl_driver_info_get(dev->driver, &req);
 	if (err)
@@ -6796,9 +6798,6 @@ static int devlink_nl_cmd_info_get_doit(struct sk_buff *skb,
 	struct sk_buff *msg;
 	int err;
 
-	if (!devlink->ops->info_get)
-		return -EOPNOTSUPP;
-
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 	if (!msg)
 		return -ENOMEM;
@@ -6824,7 +6823,7 @@ static int devlink_nl_cmd_info_get_dumpit(struct sk_buff *msg,
 	int err = 0;
 
 	devlinks_xa_for_each_registered_get(sock_net(msg->sk), index, devlink) {
-		if (idx < start || !devlink->ops->info_get)
+		if (idx < start)
 			goto inc;
 
 		devl_lock(devlink);
-- 
2.25.1