nfp: add devlink_eswitch_mode_set callback

Our previous apps all assumed to use only one eswitch mode (legacy
or switchdev) without the ability to change it.  ABM NIC will
want to support the switch so plumb devlink_eswitch_mode_set through.
The devlink_eswitch_mode_set is expected to spawn representors and
potentially devlink ports so it's called under big devlink lock and
pf->lock.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/nfp_app.h

@@ -97,6 +97,7 @@ extern const struct nfp_app_type app_abm;
  * @bpf:	BPF ndo offload-related calls
  * @xdp_offload:    offload an XDP program
  * @eswitch_mode_get:    get SR-IOV eswitch mode
+ * @eswitch_mode_set:    set SR-IOV eswitch mode (under pf->lock)
  * @sriov_enable: app-specific sriov initialisation
  * @sriov_disable: app-specific sriov clean-up
  * @repr_get:	get representor netdev
@@ -148,6 +149,7 @@ struct nfp_app_type {
 	void (*sriov_disable)(struct nfp_app *app);
 
 	enum devlink_eswitch_mode (*eswitch_mode_get)(struct nfp_app *app);
+	int (*eswitch_mode_set)(struct nfp_app *app, u16 mode);
 	struct net_device *(*repr_get)(struct nfp_app *app, u32 id);
 };
 
@@ -372,6 +374,13 @@ static inline int nfp_app_eswitch_mode_get(struct nfp_app *app, u16 *mode)
 	return 0;
 }
 
+static inline int nfp_app_eswitch_mode_set(struct nfp_app *app, u16 mode)
+{
+	if (!app->type->eswitch_mode_set)
+		return -EOPNOTSUPP;
+	return app->type->eswitch_mode_set(app, mode);
+}
+
 static inline int nfp_app_sriov_enable(struct nfp_app *app, int num_vfs)
 {
 	if (!app || !app->type->sriov_enable)

drivers/net/ethernet/netronome/nfp/nfp_devlink.c

@@ -176,12 +176,25 @@ static int nfp_devlink_eswitch_mode_get(struct devlink *devlink, u16 *mode)
 	return nfp_app_eswitch_mode_get(pf->app, mode);
 }
 
+static int nfp_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode)
+{
+	struct nfp_pf *pf = devlink_priv(devlink);
+	int ret;
+
+	mutex_lock(&pf->lock);
+	ret = nfp_app_eswitch_mode_set(pf->app, mode);
+	mutex_unlock(&pf->lock);
+
+	return ret;
+}
+
 const struct devlink_ops nfp_devlink_ops = {
 	.port_split		= nfp_devlink_port_split,
 	.port_unsplit		= nfp_devlink_port_unsplit,
 	.sb_pool_get		= nfp_devlink_sb_pool_get,
 	.sb_pool_set		= nfp_devlink_sb_pool_set,
 	.eswitch_mode_get	= nfp_devlink_eswitch_mode_get,
+	.eswitch_mode_set	= nfp_devlink_eswitch_mode_set,
 };
 
 int nfp_devlink_port_register(struct nfp_app *app, struct nfp_port *port)