Merge branch 'autoload-dsa-tagging-driver-when-dynamically-changing-protocol'

Vladimir Oltean says:

====================
Autoload DSA tagging driver when dynamically changing protocol

This patch set solves the issue reported by Michael and Heiko here:
https://lore.kernel.org/lkml/20221027113248.420216-1-michael@walle.cc/
making full use of Michael's suggestion of having two modaliases: one
gets used for loading the tagging protocol when it's the default one
reported by the switch driver, the other gets loaded at user's request,
by name.

  # modinfo tag_ocelot
  filename:       /lib/modules/6.1.0-rc4+/kernel/net/dsa/tag_ocelot.ko
  license:        GPL v2
  alias:          dsa_tag:seville
  alias:          dsa_tag:id-21
  alias:          dsa_tag:ocelot
  alias:          dsa_tag:id-15
  depends:        dsa_core
  intree:         Y
  name:           tag_ocelot
  vermagic:       6.1.0-rc4+ SMP preempt mod_unload modversions aarch64

Tested on NXP LS1028A-RDB with the following device tree addition:

&mscc_felix_port4 {
	dsa-tag-protocol = "ocelot-8021q";
};

&mscc_felix_port5 {
	dsa-tag-protocol = "ocelot-8021q";
};

CONFIG_NET_DSA and everything that depends on it is built as module.
Everything auto-loads, and "cat /sys/class/net/eno2/dsa/tagging" shows
"ocelot-8021q". Traffic works as well. Furthermore, "echo ocelot-8021q"
into the aforementioned sysfs file now auto-loads the driver for it.
====================

Link: https://lore.kernel.org/r/20221115011847.2843127-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

22 files changed, 191 insertions, 130 deletions

diff --git a/include/net/dsa.h b/include/net/dsa.h
index dde364688739..82da44561f4c 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -118,10 +118,6 @@ struct dsa_netdevice_ops {
 			     int cmd);
 };
 
-#define DSA_TAG_DRIVER_ALIAS "dsa_tag-"
-#define MODULE_ALIAS_DSA_TAG_DRIVER(__proto)				\
-	MODULE_ALIAS(DSA_TAG_DRIVER_ALIAS __stringify(__proto##_VALUE))
-
 struct dsa_lag {
 	struct net_device *dev;
 	unsigned int id;
@@ -1400,70 +1396,4 @@ static inline bool dsa_slave_dev_check(const struct net_device *dev)
 netdev_tx_t dsa_enqueue_skb(struct sk_buff *skb, struct net_device *dev);
 void dsa_port_phylink_mac_change(struct dsa_switch *ds, int port, bool up);
 
-struct dsa_tag_driver {
-	const struct dsa_device_ops *ops;
-	struct list_head list;
-	struct module *owner;
-};
-
-void dsa_tag_drivers_register(struct dsa_tag_driver *dsa_tag_driver_array[],
-			      unsigned int count,
-			      struct module *owner);
-void dsa_tag_drivers_unregister(struct dsa_tag_driver *dsa_tag_driver_array[],
-				unsigned int count);
-
-#define dsa_tag_driver_module_drivers(__dsa_tag_drivers_array, __count)	\
-static int __init dsa_tag_driver_module_init(void)			\
-{									\
-	dsa_tag_drivers_register(__dsa_tag_drivers_array, __count,	\
-				 THIS_MODULE);				\
-	return 0;							\
-}									\
-module_init(dsa_tag_driver_module_init);				\
-									\
-static void __exit dsa_tag_driver_module_exit(void)			\
-{									\
-	dsa_tag_drivers_unregister(__dsa_tag_drivers_array, __count);	\
-}									\
-module_exit(dsa_tag_driver_module_exit)
-
-/**
- * module_dsa_tag_drivers() - Helper macro for registering DSA tag
- * drivers
- * @__ops_array: Array of tag driver structures
- *
- * Helper macro for DSA tag drivers which do not do anything special
- * in module init/exit. Each module may only use this macro once, and
- * calling it replaces module_init() and module_exit().
- */
-#define module_dsa_tag_drivers(__ops_array)				\
-dsa_tag_driver_module_drivers(__ops_array, ARRAY_SIZE(__ops_array))
-
-#define DSA_TAG_DRIVER_NAME(__ops) dsa_tag_driver ## _ ## __ops
-
-/* Create a static structure we can build a linked list of dsa_tag
- * drivers
- */
-#define DSA_TAG_DRIVER(__ops)						\
-static struct dsa_tag_driver DSA_TAG_DRIVER_NAME(__ops) = {		\
-	.ops = &__ops,							\
-}
-
-/**
- * module_dsa_tag_driver() - Helper macro for registering a single DSA tag
- * driver
- * @__ops: Single tag driver structures
- *
- * Helper macro for DSA tag drivers which do not do anything special
- * in module init/exit. Each module may only use this macro once, and
- * calling it replaces module_init() and module_exit().
- */
-#define module_dsa_tag_driver(__ops)					\
-DSA_TAG_DRIVER(__ops);							\
-									\
-static struct dsa_tag_driver *dsa_tag_driver_array[] =	{		\
-	&DSA_TAG_DRIVER_NAME(__ops)					\
-};									\
-module_dsa_tag_drivers(dsa_tag_driver_array)
 #endif
-
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 6caf2ec648fd..4afd3edbd64d 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -79,16 +79,18 @@ const char *dsa_tag_protocol_to_str(const struct dsa_device_ops *ops)
 /* Function takes a reference on the module owning the tagger,
  * so dsa_tag_driver_put must be called afterwards.
  */
-const struct dsa_device_ops *dsa_find_tagger_by_name(const char *buf)
+const struct dsa_device_ops *dsa_tag_driver_get_by_name(const char *name)
 {
 	const struct dsa_device_ops *ops = ERR_PTR(-ENOPROTOOPT);
 	struct dsa_tag_driver *dsa_tag_driver;
 
+	request_module("%s%s", DSA_TAG_DRIVER_ALIAS, name);
+
 	mutex_lock(&dsa_tag_drivers_lock);
 	list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
 		const struct dsa_device_ops *tmp = dsa_tag_driver->ops;
 
-		if (!sysfs_streq(buf, tmp->name))
+		if (strcmp(name, tmp->name))
 			continue;
 
 		if (!try_module_get(dsa_tag_driver->owner))
@@ -102,13 +104,13 @@ const struct dsa_device_ops *dsa_find_tagger_by_name(const char *buf)
 	return ops;
 }
 
-const struct dsa_device_ops *dsa_tag_driver_get(int tag_protocol)
+const struct dsa_device_ops *dsa_tag_driver_get_by_id(int tag_protocol)
 {
 	struct dsa_tag_driver *dsa_tag_driver;
 	const struct dsa_device_ops *ops;
 	bool found = false;
 
-	request_module("%s%d", DSA_TAG_DRIVER_ALIAS, tag_protocol);
+	request_module("%sid-%d", DSA_TAG_DRIVER_ALIAS, tag_protocol);
 
 	mutex_lock(&dsa_tag_drivers_lock);
 	list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index d3055b49080f..f8df55e2e23a 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -1431,7 +1431,7 @@ static int dsa_port_parse_cpu(struct dsa_port *dp, struct net_device *master,
 			return -EINVAL;
 		}
 
-		tag_ops = dsa_find_tagger_by_name(user_protocol);
+		tag_ops = dsa_tag_driver_get_by_name(user_protocol);
 		if (IS_ERR(tag_ops)) {
 			dev_warn(ds->dev,
 				 "Failed to find a tagging driver for protocol %s, using default\n",
@@ -1441,7 +1441,7 @@ static int dsa_port_parse_cpu(struct dsa_port *dp, struct net_device *master,
 	}
 
 	if (!tag_ops)
-		tag_ops = dsa_tag_driver_get(default_proto);
+		tag_ops = dsa_tag_driver_get_by_id(default_proto);
 
 	if (IS_ERR(tag_ops)) {
 		if (PTR_ERR(tag_ops) == -ENOPROTOOPT)
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 71e9707d11d4..24e0ea218a35 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -17,6 +17,81 @@
 
 #define DSA_MAX_NUM_OFFLOADING_BRIDGES		BITS_PER_LONG
 
+/* Create 2 modaliases per tagging protocol, one to auto-load the module
+ * given the ID reported by get_tag_protocol(), and the other by name.
+ */
+#define DSA_TAG_DRIVER_ALIAS "dsa_tag:"
+#define MODULE_ALIAS_DSA_TAG_DRIVER(__proto, __name) \
+	MODULE_ALIAS(DSA_TAG_DRIVER_ALIAS __name); \
+	MODULE_ALIAS(DSA_TAG_DRIVER_ALIAS "id-" \
+		     __stringify(__proto##_VALUE))
+
+struct dsa_tag_driver {
+	const struct dsa_device_ops *ops;
+	struct list_head list;
+	struct module *owner;
+};
+
+void dsa_tag_drivers_register(struct dsa_tag_driver *dsa_tag_driver_array[],
+			      unsigned int count,
+			      struct module *owner);
+void dsa_tag_drivers_unregister(struct dsa_tag_driver *dsa_tag_driver_array[],
+				unsigned int count);
+
+#define dsa_tag_driver_module_drivers(__dsa_tag_drivers_array, __count)	\
+static int __init dsa_tag_driver_module_init(void)			\
+{									\
+	dsa_tag_drivers_register(__dsa_tag_drivers_array, __count,	\
+				 THIS_MODULE);				\
+	return 0;							\
+}									\
+module_init(dsa_tag_driver_module_init);				\
+									\
+static void __exit dsa_tag_driver_module_exit(void)			\
+{									\
+	dsa_tag_drivers_unregister(__dsa_tag_drivers_array, __count);	\
+}									\
+module_exit(dsa_tag_driver_module_exit)
+
+/**
+ * module_dsa_tag_drivers() - Helper macro for registering DSA tag
+ * drivers
+ * @__ops_array: Array of tag driver structures
+ *
+ * Helper macro for DSA tag drivers which do not do anything special
+ * in module init/exit. Each module may only use this macro once, and
+ * calling it replaces module_init() and module_exit().
+ */
+#define module_dsa_tag_drivers(__ops_array)				\
+dsa_tag_driver_module_drivers(__ops_array, ARRAY_SIZE(__ops_array))
+
+#define DSA_TAG_DRIVER_NAME(__ops) dsa_tag_driver ## _ ## __ops
+
+/* Create a static structure we can build a linked list of dsa_tag
+ * drivers
+ */
+#define DSA_TAG_DRIVER(__ops)						\
+static struct dsa_tag_driver DSA_TAG_DRIVER_NAME(__ops) = {		\
+	.ops = &__ops,							\
+}
+
+/**
+ * module_dsa_tag_driver() - Helper macro for registering a single DSA tag
+ * driver
+ * @__ops: Single tag driver structures
+ *
+ * Helper macro for DSA tag drivers which do not do anything special
+ * in module init/exit. Each module may only use this macro once, and
+ * calling it replaces module_init() and module_exit().
+ */
+#define module_dsa_tag_driver(__ops)					\
+DSA_TAG_DRIVER(__ops);							\
+									\
+static struct dsa_tag_driver *dsa_tag_driver_array[] =	{		\
+	&DSA_TAG_DRIVER_NAME(__ops)					\
+};									\
+module_dsa_tag_drivers(dsa_tag_driver_array)
+
 enum {
 	DSA_NOTIFIER_AGEING_TIME,
 	DSA_NOTIFIER_BRIDGE_JOIN,
@@ -168,9 +243,9 @@ struct dsa_slave_priv {
 };
 
 /* dsa.c */
-const struct dsa_device_ops *dsa_tag_driver_get(int tag_protocol);
+const struct dsa_device_ops *dsa_tag_driver_get_by_id(int tag_protocol);
+const struct dsa_device_ops *dsa_tag_driver_get_by_name(const char *name);
 void dsa_tag_driver_put(const struct dsa_device_ops *ops);
-const struct dsa_device_ops *dsa_find_tagger_by_name(const char *buf);
 
 bool dsa_db_equal(const struct dsa_db *a, const struct dsa_db *b);
 
diff --git a/net/dsa/master.c b/net/dsa/master.c
index 421de166515f..e24f02743c21 100644
--- a/net/dsa/master.c
+++ b/net/dsa/master.c
@@ -299,13 +299,24 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
 			     const char *buf, size_t count)
 {
 	const struct dsa_device_ops *new_tag_ops, *old_tag_ops;
+	const char *end = strchrnul(buf, '\n'), *name;
 	struct net_device *dev = to_net_dev(d);
 	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	size_t len = end - buf;
 	int err;
 
+	/* Empty string passed */
+	if (!len)
+		return -ENOPROTOOPT;
+
+	name = kstrndup(buf, len, GFP_KERNEL);
+	if (!name)
+		return -ENOMEM;
+
 	old_tag_ops = cpu_dp->tag_ops;
-	new_tag_ops = dsa_find_tagger_by_name(buf);
-	/* Bad tagger name, or module is not loaded? */
+	new_tag_ops = dsa_tag_driver_get_by_name(name);
+	kfree(name);
+	/* Bad tagger name? */
 	if (IS_ERR(new_tag_ops))
 		return PTR_ERR(new_tag_ops);
 
diff --git a/net/dsa/tag_ar9331.c b/net/dsa/tag_ar9331.c
index 8a02ac44282f..bfa161a4f502 100644
--- a/net/dsa/tag_ar9331.c
+++ b/net/dsa/tag_ar9331.c
@@ -9,6 +9,8 @@
 
 #include "dsa_priv.h"
 
+#define AR9331_NAME			"ar9331"
+
 #define AR9331_HDR_LEN			2
 #define AR9331_HDR_VERSION		1
 
@@ -80,7 +82,7 @@ static struct sk_buff *ar9331_tag_rcv(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops ar9331_netdev_ops = {
-	.name	= "ar9331",
+	.name	= AR9331_NAME,
 	.proto	= DSA_TAG_PROTO_AR9331,
 	.xmit	= ar9331_tag_xmit,
 	.rcv	= ar9331_tag_rcv,
@@ -88,5 +90,5 @@ static const struct dsa_device_ops ar9331_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL v2");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_AR9331);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_AR9331, AR9331_NAME);
 module_dsa_tag_driver(ar9331_netdev_ops);
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 16889ea3e0a7..9e7477ed70f1 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -12,6 +12,10 @@
 
 #include "dsa_priv.h"
 
+#define BRCM_NAME		"brcm"
+#define BRCM_LEGACY_NAME	"brcm-legacy"
+#define BRCM_PREPEND_NAME	"brcm-prepend"
+
 /* Legacy Broadcom tag (6 bytes) */
 #define BRCM_LEG_TAG_LEN	6
 
@@ -196,7 +200,7 @@ static struct sk_buff *brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops brcm_netdev_ops = {
-	.name	= "brcm",
+	.name	= BRCM_NAME,
 	.proto	= DSA_TAG_PROTO_BRCM,
 	.xmit	= brcm_tag_xmit,
 	.rcv	= brcm_tag_rcv,
@@ -204,7 +208,7 @@ static const struct dsa_device_ops brcm_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(brcm_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM, BRCM_NAME);
 #endif
 
 #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
@@ -273,7 +277,7 @@ static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops brcm_legacy_netdev_ops = {
-	.name = "brcm-legacy",
+	.name = BRCM_LEGACY_NAME,
 	.proto = DSA_TAG_PROTO_BRCM_LEGACY,
 	.xmit = brcm_leg_tag_xmit,
 	.rcv = brcm_leg_tag_rcv,
@@ -281,7 +285,7 @@ static const struct dsa_device_ops brcm_legacy_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(brcm_legacy_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY, BRCM_LEGACY_NAME);
 #endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY */
 
 #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
@@ -300,7 +304,7 @@ static struct sk_buff *brcm_tag_rcv_prepend(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops brcm_prepend_netdev_ops = {
-	.name	= "brcm-prepend",
+	.name	= BRCM_PREPEND_NAME,
 	.proto	= DSA_TAG_PROTO_BRCM_PREPEND,
 	.xmit	= brcm_tag_xmit_prepend,
 	.rcv	= brcm_tag_rcv_prepend,
@@ -308,7 +312,7 @@ static const struct dsa_device_ops brcm_prepend_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(brcm_prepend_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_PREPEND);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_PREPEND, BRCM_PREPEND_NAME);
 #endif
 
 static struct dsa_tag_driver *dsa_tag_driver_array[] =	{
diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
index e4b6e3f2a3db..9fe77f5cc759 100644
--- a/net/dsa/tag_dsa.c
+++ b/net/dsa/tag_dsa.c
@@ -52,6 +52,9 @@
 
 #include "dsa_priv.h"
 
+#define DSA_NAME	"dsa"
+#define EDSA_NAME	"edsa"
+
 #define DSA_HLEN	4
 
 /**
@@ -339,7 +342,7 @@ static struct sk_buff *dsa_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops dsa_netdev_ops = {
-	.name	  = "dsa",
+	.name	  = DSA_NAME,
 	.proto	  = DSA_TAG_PROTO_DSA,
 	.xmit	  = dsa_xmit,
 	.rcv	  = dsa_rcv,
@@ -347,7 +350,7 @@ static const struct dsa_device_ops dsa_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(dsa_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_DSA);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_DSA, DSA_NAME);
 #endif	/* CONFIG_NET_DSA_TAG_DSA */
 
 #if IS_ENABLED(CONFIG_NET_DSA_TAG_EDSA)
@@ -381,7 +384,7 @@ static struct sk_buff *edsa_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops edsa_netdev_ops = {
-	.name	  = "edsa",
+	.name	  = EDSA_NAME,
 	.proto	  = DSA_TAG_PROTO_EDSA,
 	.xmit	  = edsa_xmit,
 	.rcv	  = edsa_rcv,
@@ -389,7 +392,7 @@ static const struct dsa_device_ops edsa_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(edsa_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_EDSA);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_EDSA, EDSA_NAME);
 #endif	/* CONFIG_NET_DSA_TAG_EDSA */
 
 static struct dsa_tag_driver *dsa_tag_drivers[] = {
diff --git a/net/dsa/tag_gswip.c b/net/dsa/tag_gswip.c
index df7140984da3..020050dff3e4 100644
--- a/net/dsa/tag_gswip.c
+++ b/net/dsa/tag_gswip.c
@@ -12,6 +12,8 @@
 
 #include "dsa_priv.h"
 
+#define GSWIP_NAME			"gswip"
+
 #define GSWIP_TX_HEADER_LEN		4
 
 /* special tag in TX path header */
@@ -98,7 +100,7 @@ static struct sk_buff *gswip_tag_rcv(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops gswip_netdev_ops = {
-	.name = "gswip",
+	.name = GSWIP_NAME,
 	.proto	= DSA_TAG_PROTO_GSWIP,
 	.xmit = gswip_tag_xmit,
 	.rcv = gswip_tag_rcv,
@@ -106,6 +108,6 @@ static const struct dsa_device_ops gswip_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_GSWIP);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_GSWIP, GSWIP_NAME);
 
 module_dsa_tag_driver(gswip_netdev_ops);
diff --git a/net/dsa/tag_hellcreek.c b/net/dsa/tag_hellcreek.c
index 846588c0070a..03fd5f2877c8 100644
--- a/net/dsa/tag_hellcreek.c
+++ b/net/dsa/tag_hellcreek.c
@@ -13,6 +13,8 @@
 
 #include "dsa_priv.h"
 
+#define HELLCREEK_NAME		"hellcreek"
+
 #define HELLCREEK_TAG_LEN	1
 
 static struct sk_buff *hellcreek_xmit(struct sk_buff *skb,
@@ -57,7 +59,7 @@ static struct sk_buff *hellcreek_rcv(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops hellcreek_netdev_ops = {
-	.name	  = "hellcreek",
+	.name	  = HELLCREEK_NAME,
 	.proto	  = DSA_TAG_PROTO_HELLCREEK,
 	.xmit	  = hellcreek_xmit,
 	.rcv	  = hellcreek_rcv,
@@ -65,6 +67,6 @@ static const struct dsa_device_ops hellcreek_netdev_ops = {
 };
 
 MODULE_LICENSE("Dual MIT/GPL");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_HELLCREEK);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_HELLCREEK, HELLCREEK_NAME);
 
 module_dsa_tag_driver(hellcreek_netdev_ops);
diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c
index 38fa19c1e2d5..37db5156f9a3 100644
--- a/net/dsa/tag_ksz.c
+++ b/net/dsa/tag_ksz.c
@@ -9,6 +9,11 @@
 #include <net/dsa.h>
 #include "dsa_priv.h"
 
+#define KSZ8795_NAME "ksz8795"
+#define KSZ9477_NAME "ksz9477"
+#define KSZ9893_NAME "ksz9893"
+#define LAN937X_NAME "lan937x"
+
 /* Typically only one byte is used for tail tag. */
 #define KSZ_EGRESS_TAG_LEN		1
 #define KSZ_INGRESS_TAG_LEN		1
@@ -74,7 +79,7 @@ static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops ksz8795_netdev_ops = {
-	.name	= "ksz8795",
+	.name	= KSZ8795_NAME,
 	.proto	= DSA_TAG_PROTO_KSZ8795,
 	.xmit	= ksz8795_xmit,
 	.rcv	= ksz8795_rcv,
@@ -82,7 +87,7 @@ static const struct dsa_device_ops ksz8795_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(ksz8795_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME);
 
 /*
  * For Ingress (Host -> KSZ9477), 2 bytes are added before FCS.
@@ -147,7 +152,7 @@ static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops ksz9477_netdev_ops = {
-	.name	= "ksz9477",
+	.name	= KSZ9477_NAME,
 	.proto	= DSA_TAG_PROTO_KSZ9477,
 	.xmit	= ksz9477_xmit,
 	.rcv	= ksz9477_rcv,
@@ -155,7 +160,7 @@ static const struct dsa_device_ops ksz9477_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(ksz9477_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477, KSZ9477_NAME);
 
 #define KSZ9893_TAIL_TAG_OVERRIDE	BIT(5)
 #define KSZ9893_TAIL_TAG_LOOKUP		BIT(6)
@@ -183,7 +188,7 @@ static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops ksz9893_netdev_ops = {
-	.name	= "ksz9893",
+	.name	= KSZ9893_NAME,
 	.proto	= DSA_TAG_PROTO_KSZ9893,
 	.xmit	= ksz9893_xmit,
 	.rcv	= ksz9477_rcv,
@@ -191,7 +196,7 @@ static const struct dsa_device_ops ksz9893_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(ksz9893_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME);
 
 /* For xmit, 2 bytes are added before FCS.
  * ---------------------------------------------------------------------------
@@ -241,7 +246,7 @@ static struct sk_buff *lan937x_xmit(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops lan937x_netdev_ops = {
-	.name	= "lan937x",
+	.name	= LAN937X_NAME,
 	.proto	= DSA_TAG_PROTO_LAN937X,
 	.xmit	= lan937x_xmit,
 	.rcv	= ksz9477_rcv,
@@ -249,7 +254,7 @@ static const struct dsa_device_ops lan937x_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(lan937x_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X, LAN937X_NAME);
 
 static struct dsa_tag_driver *dsa_tag_driver_array[] = {
 	&DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
diff --git a/net/dsa/tag_lan9303.c b/net/dsa/tag_lan9303.c
index 98d7d7120bab..4118292ed218 100644
--- a/net/dsa/tag_lan9303.c
+++ b/net/dsa/tag_lan9303.c
@@ -30,6 +30,8 @@
  * Required when no forwarding between the external ports should happen.
  */
 
+#define LAN9303_NAME "lan9303"
+
 #define LAN9303_TAG_LEN 4
 # define LAN9303_TAG_TX_USE_ALR BIT(3)
 # define LAN9303_TAG_TX_STP_OVERRIDE BIT(4)
@@ -110,7 +112,7 @@ static struct sk_buff *lan9303_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops lan9303_netdev_ops = {
-	.name = "lan9303",
+	.name = LAN9303_NAME,
 	.proto	= DSA_TAG_PROTO_LAN9303,
 	.xmit = lan9303_xmit,
 	.rcv = lan9303_rcv,
@@ -118,6 +120,6 @@ static const struct dsa_device_ops lan9303_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN9303);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN9303, LAN9303_NAME);
 
 module_dsa_tag_driver(lan9303_netdev_ops);
diff --git a/net/dsa/tag_mtk.c b/net/dsa/tag_mtk.c
index 415d8ece242a..ba37495ab5f4 100644
--- a/net/dsa/tag_mtk.c
+++ b/net/dsa/tag_mtk.c
@@ -10,6 +10,8 @@
 
 #include "dsa_priv.h"
 
+#define MTK_NAME		"mtk"
+
 #define MTK_HDR_LEN		4
 #define MTK_HDR_XMIT_UNTAGGED		0
 #define MTK_HDR_XMIT_TAGGED_TPID_8100	1
@@ -91,7 +93,7 @@ static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops mtk_netdev_ops = {
-	.name		= "mtk",
+	.name		= MTK_NAME,
 	.proto		= DSA_TAG_PROTO_MTK,
 	.xmit		= mtk_tag_xmit,
 	.rcv		= mtk_tag_rcv,
@@ -99,6 +101,6 @@ static const struct dsa_device_ops mtk_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_MTK);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_MTK, MTK_NAME);
 
 module_dsa_tag_driver(mtk_netdev_ops);
diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c
index 0d81f172b7a6..8cc31ab47e28 100644
--- a/net/dsa/tag_ocelot.c
+++ b/net/dsa/tag_ocelot.c
@@ -4,6 +4,9 @@
 #include <linux/dsa/ocelot.h>
 #include "dsa_priv.h"
 
+#define OCELOT_NAME	"ocelot"
+#define SEVILLE_NAME	"seville"
+
 /* If the port is under a VLAN-aware bridge, remove the VLAN header from the
  * payload and move it into the DSA tag, which will make the switch classify
  * the packet to the bridge VLAN. Otherwise, leave the classified VLAN at zero,
@@ -183,7 +186,7 @@ static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops ocelot_netdev_ops = {
-	.name			= "ocelot",
+	.name			= OCELOT_NAME,
 	.proto			= DSA_TAG_PROTO_OCELOT,
 	.xmit			= ocelot_xmit,
 	.rcv			= ocelot_rcv,
@@ -192,10 +195,10 @@ static const struct dsa_device_ops ocelot_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(ocelot_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT, OCELOT_NAME);
 
 static const struct dsa_device_ops seville_netdev_ops = {
-	.name			= "seville",
+	.name			= SEVILLE_NAME,
 	.proto			= DSA_TAG_PROTO_SEVILLE,
 	.xmit			= seville_xmit,
 	.rcv			= ocelot_rcv,
@@ -204,7 +207,7 @@ static const struct dsa_device_ops seville_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(seville_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SEVILLE);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SEVILLE, SEVILLE_NAME);
 
 static struct dsa_tag_driver *ocelot_tag_driver_array[] = {
 	&DSA_TAG_DRIVER_NAME(ocelot_netdev_ops),
diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c
index 37ccf00404ea..d1ec68001487 100644
--- a/net/dsa/tag_ocelot_8021q.c
+++ b/net/dsa/tag_ocelot_8021q.c
@@ -12,6 +12,8 @@
 #include <linux/dsa/ocelot.h>
 #include "dsa_priv.h"
 
+#define OCELOT_8021Q_NAME "ocelot-8021q"
+
 struct ocelot_8021q_tagger_private {
 	struct ocelot_8021q_tagger_data data; /* Must be first */
 	struct kthread_worker *xmit_worker;
@@ -119,7 +121,7 @@ static int ocelot_connect(struct dsa_switch *ds)
 }
 
 static const struct dsa_device_ops ocelot_8021q_netdev_ops = {
-	.name			= "ocelot-8021q",
+	.name			= OCELOT_8021Q_NAME,
 	.proto			= DSA_TAG_PROTO_OCELOT_8021Q,
 	.xmit			= ocelot_xmit,
 	.rcv			= ocelot_rcv,
@@ -130,6 +132,6 @@ static const struct dsa_device_ops ocelot_8021q_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL v2");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT_8021Q);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT_8021Q, OCELOT_8021Q_NAME);
 
 module_dsa_tag_driver(ocelot_8021q_netdev_ops);
diff --git a/net/dsa/tag_qca.c b/net/dsa/tag_qca.c
index 57d2e00f1e5d..73d6e111228d 100644
--- a/net/dsa/tag_qca.c
+++ b/net/dsa/tag_qca.c
@@ -10,6 +10,8 @@
 
 #include "dsa_priv.h"
 
+#define QCA_NAME "qca"
+
 static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_port *dp = dsa_slave_to_port(dev);
@@ -107,7 +109,7 @@ static void qca_tag_disconnect(struct dsa_switch *ds)
 }
 
 static const struct dsa_device_ops qca_netdev_ops = {
-	.name	= "qca",
+	.name	= QCA_NAME,
 	.proto	= DSA_TAG_PROTO_QCA,
 	.connect = qca_tag_connect,
 	.disconnect = qca_tag_disconnect,
@@ -118,6 +120,6 @@ static const struct dsa_device_ops qca_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_QCA);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_QCA, QCA_NAME);
 
 module_dsa_tag_driver(qca_netdev_ops);
diff --git a/net/dsa/tag_rtl4_a.c b/net/dsa/tag_rtl4_a.c
index 6d928ee3ef7a..18b52d77d200 100644
--- a/net/dsa/tag_rtl4_a.c
+++ b/net/dsa/tag_rtl4_a.c
@@ -20,6 +20,8 @@
 
 #include "dsa_priv.h"
 
+#define RTL4_A_NAME		"rtl4a"
+
 #define RTL4_A_HDR_LEN		4
 #define RTL4_A_ETHERTYPE	0x8899
 #define RTL4_A_PROTOCOL_SHIFT	12
@@ -112,7 +114,7 @@ static struct sk_buff *rtl4a_tag_rcv(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops rtl4a_netdev_ops = {
-	.name	= "rtl4a",
+	.name	= RTL4_A_NAME,
 	.proto	= DSA_TAG_PROTO_RTL4_A,
 	.xmit	= rtl4a_tag_xmit,
 	.rcv	= rtl4a_tag_rcv,
@@ -121,4 +123,4 @@ static const struct dsa_device_ops rtl4a_netdev_ops = {
 module_dsa_tag_driver(rtl4a_netdev_ops);
 
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL4_A);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL4_A, RTL4_A_NAME);
diff --git a/net/dsa/tag_rtl8_4.c b/net/dsa/tag_rtl8_4.c
index a593ead7ff26..030a8cf0ad48 100644
--- a/net/dsa/tag_rtl8_4.c
+++ b/net/dsa/tag_rtl8_4.c
@@ -84,6 +84,9 @@
  * 0x04 = RTL8365MB DSA protocol
  */
 
+#define RTL8_4_NAME			"rtl8_4"
+#define RTL8_4T_NAME			"rtl8_4t"
+
 #define RTL8_4_TAG_LEN			8
 
 #define RTL8_4_PROTOCOL			GENMASK(15, 8)
@@ -234,7 +237,7 @@ static const struct dsa_device_ops rtl8_4_netdev_ops = {
 
 DSA_TAG_DRIVER(rtl8_4_netdev_ops);
 
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL8_4);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL8_4, RTL8_4_NAME);
 
 /* Tail version */
 static const struct dsa_device_ops rtl8_4t_netdev_ops = {
@@ -247,7 +250,7 @@ static const struct dsa_device_ops rtl8_4t_netdev_ops = {
 
 DSA_TAG_DRIVER(rtl8_4t_netdev_ops);
 
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL8_4T);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL8_4T, RTL8_4T_NAME);
 
 static struct dsa_tag_driver *dsa_tag_drivers[] = {
 	&DSA_TAG_DRIVER_NAME(rtl8_4_netdev_ops),
diff --git a/net/dsa/tag_rzn1_a5psw.c b/net/dsa/tag_rzn1_a5psw.c
index e2a5ee6ae688..b9135069f9fc 100644
--- a/net/dsa/tag_rzn1_a5psw.c
+++ b/net/dsa/tag_rzn1_a5psw.c
@@ -22,6 +22,8 @@
  * See struct a5psw_tag for layout
  */
 
+#define A5PSW_NAME			"a5psw"
+
 #define ETH_P_DSA_A5PSW			0xE001
 #define A5PSW_TAG_LEN			8
 #define A5PSW_CTRL_DATA_FORCE_FORWARD	BIT(0)
@@ -101,7 +103,7 @@ static struct sk_buff *a5psw_tag_rcv(struct sk_buff *skb,
 }
 
 static const struct dsa_device_ops a5psw_netdev_ops = {
-	.name	= "a5psw",
+	.name	= A5PSW_NAME,
 	.proto	= DSA_TAG_PROTO_RZN1_A5PSW,
 	.xmit	= a5psw_tag_xmit,
 	.rcv	= a5psw_tag_rcv,
@@ -109,5 +111,5 @@ static const struct dsa_device_ops a5psw_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL v2");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_A5PSW);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_A5PSW, A5PSW_NAME);
 module_dsa_tag_driver(a5psw_netdev_ops);
diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 83e4136516b0..3b6e642a90e9 100644
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -7,6 +7,9 @@
 #include <linux/packing.h>
 #include "dsa_priv.h"
 
+#define SJA1105_NAME				"sja1105"
+#define SJA1110_NAME				"sja1110"
+
 /* Is this a TX or an RX header? */
 #define SJA1110_HEADER_HOST_TO_SWITCH		BIT(15)
 
@@ -786,7 +789,7 @@ static int sja1105_connect(struct dsa_switch *ds)
 }
 
 static const struct dsa_device_ops sja1105_netdev_ops = {
-	.name = "sja1105",
+	.name = SJA1105_NAME,
 	.proto = DSA_TAG_PROTO_SJA1105,
 	.xmit = sja1105_xmit,
 	.rcv = sja1105_rcv,
@@ -798,10 +801,10 @@ static const struct dsa_device_ops sja1105_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(sja1105_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105, SJA1105_NAME);
 
 static const struct dsa_device_ops sja1110_netdev_ops = {
-	.name = "sja1110",
+	.name = SJA1110_NAME,
 	.proto = DSA_TAG_PROTO_SJA1110,
 	.xmit = sja1110_xmit,
 	.rcv = sja1110_rcv,
@@ -813,7 +816,7 @@ static const struct dsa_device_ops sja1110_netdev_ops = {
 };
 
 DSA_TAG_DRIVER(sja1110_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1110);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1110, SJA1110_NAME);
 
 static struct dsa_tag_driver *sja1105_tag_driver_array[] = {
 	&DSA_TAG_DRIVER_NAME(sja1105_netdev_ops),
diff --git a/net/dsa/tag_trailer.c b/net/dsa/tag_trailer.c
index 5749ba85c2b8..8754dfe680f6 100644
--- a/net/dsa/tag_trailer.c
+++ b/net/dsa/tag_trailer.c
@@ -10,6 +10,8 @@
 
 #include "dsa_priv.h"
 
+#define TRAILER_NAME "trailer"
+
 static struct sk_buff *trailer_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_port *dp = dsa_slave_to_port(dev);
@@ -50,7 +52,7 @@ static struct sk_buff *trailer_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops trailer_netdev_ops = {
-	.name	= "trailer",
+	.name	= TRAILER_NAME,
 	.proto	= DSA_TAG_PROTO_TRAILER,
 	.xmit	= trailer_xmit,
 	.rcv	= trailer_rcv,
@@ -58,6 +60,6 @@ static const struct dsa_device_ops trailer_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_TRAILER);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_TRAILER, TRAILER_NAME);
 
 module_dsa_tag_driver(trailer_netdev_ops);
diff --git a/net/dsa/tag_xrs700x.c b/net/dsa/tag_xrs700x.c
index ff442b8af636..dc935dd90f98 100644
--- a/net/dsa/tag_xrs700x.c
+++ b/net/dsa/tag_xrs700x.c
@@ -9,6 +9,8 @@
 
 #include "dsa_priv.h"
 
+#define XRS700X_NAME "xrs700x"
+
 static struct sk_buff *xrs700x_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_port *partner, *dp = dsa_slave_to_port(dev);
@@ -51,7 +53,7 @@ static struct sk_buff *xrs700x_rcv(struct sk_buff *skb, struct net_device *dev)
 }
 
 static const struct dsa_device_ops xrs700x_netdev_ops = {
-	.name	= "xrs700x",
+	.name	= XRS700X_NAME,
 	.proto	= DSA_TAG_PROTO_XRS700X,
 	.xmit	= xrs700x_xmit,
 	.rcv	= xrs700x_rcv,
@@ -59,6 +61,6 @@ static const struct dsa_device_ops xrs700x_netdev_ops = {
 };
 
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_XRS700X);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_XRS700X, XRS700X_NAME);
 
 module_dsa_tag_driver(xrs700x_netdev_ops);