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

Commit Message

Vincent Mailhol Nov. 29, 2022, 12:05 a.m. UTC

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 <[e-mail]>
---
 net/core/devlink.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

Comments

Jacob Keller Nov. 29, 2022, 12:24 a.m. UTC | #1

> -----Original Message-----
> From: Intel-wired-lan <[e-mail]> On Behalf Of
> Vincent Mailhol
> Sent: Monday, November 28, 2022 4:06 PM
> To: Jiri Pirko <[e-mail]>; [e-mail]; Jakub Kicinski
> <[e-mail]>
> Cc: Andrew Lunn <[e-mail]>; Shijith Thotton <[e-mail]>;
> Simon Horman <[e-mail]>; Kurt Kanzenbach
> <[e-mail]>; Eric Dumazet <[e-mail]>; Jerin Jacob
> <[e-mail]>; Subbaraya Sundeep <[e-mail]>; Ioana
> Ciornei <[e-mail]>; [e-mail]; Linu Cherian
> <[e-mail]>; Florian Fainelli <[e-mail]>; Herbert Xu
> <[e-mail]>; Leon Romanovsky <[e-mail]>; linux-
> [e-mail]; Shalom Toledo <[e-mail]>; Srujana
> Challa <[e-mail]>; Minghao Chi <[e-mail]>; Hao
> Chen <[e-mail]>; Guangbin Huang
> <[e-mail]>; Shannon Nelson <[e-mail]>;
> [e-mail]; Vadim Fedorenko <[e-mail]>; Paolo
> Abeni <[e-mail]>; Yisen Zhuang <[e-mail]>; Sunil
> Goutham <[e-mail]>; Ariel Elior <[e-mail]>; Ido
> Schimmel <[e-mail]>; Richard Cochran <[e-mail]>;
> Arnaud Ebalard <[e-mail]>; Jiri Pirko <[e-mail]>; Michael
> Chan <[e-mail]>; Vincent Mailhol
> <[e-mail]>; Petr Machata <[e-mail]>; Salil Mehta
> <[e-mail]>; Dimitris Michailidis <[e-mail]>;
> Manish Chopra <[e-mail]>; Boris Brezillon
> <[e-mail]>; [e-mail]; Vadim Pasternak
> <[e-mail]>; [e-mail]; David S . Miller
> <[e-mail]>; Taras Chornyi <[e-mail]>; hariprasad
> <[e-mail]>; [e-mail]; Jonathan Lemon
> <[e-mail]>; Vladimir Oltean <[e-mail]>; Saeed
> Mahameed <[e-mail]>; Geetha sowjanya <[e-mail]>
> Subject: [Intel-wired-lan] [PATCH net-next v5 3/4] net: devlink: make the
> devlink_ops::info_get() callback optional
> 
> 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.
> 

Makes sense to me.

Thanks,
Jake

Jiri Pirko Nov. 29, 2022, 8:26 a.m. UTC | #2

Tue, Nov 29, 2022 at 01:05:49AM CET, [e-mail] wrote:
>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 <[e-mail]>

Reviewed-by: Jiri Pirko <[e-mail]>

Patch

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);