[patch net-next RFC] net: dsa: move port_setup/teardown to be called outside devlink port registered area

[Jiri Pirko <jiri@resnulli.us>]

From: Jiri Pirko <jiri@nvidia.com>

Move port_setup() op to be called before devlink_port_register() and
port_teardown() after devlink_port_unregister().

RFC note: I don't see why this would not work, but I have no way to
test this does not break things. But I think it makes sense to move this
alongside the rest of the devlink port code, the reinit() function
also gets much nicer, as clearly the fact that
port_setup()->devlink_port_region_create() was called in dsa_port_setup
did not fit the flow.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 net/dsa/dsa2.c | 64 +++++++++++++++++---------------------------------
 1 file changed, 21 insertions(+), 43 deletions(-)

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index cac48a741f27..a8b6c6434df2 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -451,19 +451,12 @@ static int dsa_port_setup(struct dsa_port *dp)
 {
 	struct devlink_port *dlp = &dp->devlink_port;
 	bool dsa_port_link_registered = false;
-	struct dsa_switch *ds = dp->ds;
 	bool dsa_port_enabled = false;
 	int err = 0;
 
 	if (dp->setup)
 		return 0;
 
-	if (ds->ops->port_setup) {
-		err = ds->ops->port_setup(ds, dp->index);
-		if (err)
-			return err;
-	}
-
 	switch (dp->type) {
 	case DSA_PORT_TYPE_UNUSED:
 		dsa_port_disable(dp);
@@ -506,11 +499,6 @@ static int dsa_port_setup(struct dsa_port *dp)
 		dsa_port_disable(dp);
 	if (err && dsa_port_link_registered)
 		dsa_port_link_unregister_of(dp);
-	if (err) {
-		if (ds->ops->port_teardown)
-			ds->ops->port_teardown(ds, dp->index);
-		return err;
-	}
 
 	dp->setup = true;
 
@@ -523,10 +511,17 @@ static int dsa_port_devlink_setup(struct dsa_port *dp)
 	struct dsa_switch_tree *dst = dp->ds->dst;
 	struct devlink_port_attrs attrs = {};
 	struct devlink *dl = dp->ds->devlink;
+	struct dsa_switch *ds = dp->ds;
 	const unsigned char *id;
 	unsigned char len;
 	int err;
 
+	if (ds->ops->port_setup) {
+		err = ds->ops->port_setup(ds, dp->index);
+		if (err)
+			return err;
+	}
+
 	id = (const unsigned char *)&dst->index;
 	len = sizeof(dst->index);
 
@@ -552,24 +547,23 @@ static int dsa_port_devlink_setup(struct dsa_port *dp)
 
 	devlink_port_attrs_set(dlp, &attrs);
 	err = devlink_port_register(dl, dlp, dp->index);
+	if (err) {
+		if (ds->ops->port_teardown)
+			ds->ops->port_teardown(ds, dp->index);
+		return err;
+	}
+	dp->devlink_port_setup = true;
 
-	if (!err)
-		dp->devlink_port_setup = true;
-
-	return err;
+	return 0;
 }
 
 static void dsa_port_teardown(struct dsa_port *dp)
 {
 	struct devlink_port *dlp = &dp->devlink_port;
-	struct dsa_switch *ds = dp->ds;
 
 	if (!dp->setup)
 		return;
 
-	if (ds->ops->port_teardown)
-		ds->ops->port_teardown(ds, dp->index);
-
 	devlink_port_type_clear(dlp);
 
 	switch (dp->type) {
@@ -597,40 +591,24 @@ static void dsa_port_teardown(struct dsa_port *dp)
 static void dsa_port_devlink_teardown(struct dsa_port *dp)
 {
 	struct devlink_port *dlp = &dp->devlink_port;
+	struct dsa_switch *ds = dp->ds;
 
-	if (dp->devlink_port_setup)
+	if (dp->devlink_port_setup) {
 		devlink_port_unregister(dlp);
+		if (ds->ops->port_teardown)
+			ds->ops->port_teardown(ds, dp->index);
+	}
 	dp->devlink_port_setup = false;
 }
 
 /* Destroy the current devlink port, and create a new one which has the UNUSED
- * flavour. At this point, any call to ds->ops->port_setup has been already
- * balanced out by a call to ds->ops->port_teardown, so we know that any
- * devlink port regions the driver had are now unregistered. We then call its
- * ds->ops->port_setup again, in order for the driver to re-create them on the
- * new devlink port.
+ * flavour.
  */
 static int dsa_port_reinit_as_unused(struct dsa_port *dp)
 {
-	struct dsa_switch *ds = dp->ds;
-	int err;
-
 	dsa_port_devlink_teardown(dp);
 	dp->type = DSA_PORT_TYPE_UNUSED;
-	err = dsa_port_devlink_setup(dp);
-	if (err)
-		return err;
-
-	if (ds->ops->port_setup) {
-		/* On error, leave the devlink port registered,
-		 * dsa_switch_teardown will clean it up later.
-		 */
-		err = ds->ops->port_setup(ds, dp->index);
-		if (err)
-			return err;
-	}
-
-	return 0;
+	return dsa_port_devlink_setup(dp);
 }
 
 static int dsa_devlink_info_get(struct devlink *dl,
-- 
2.35.3