[net-next 07/17] can: dev: move netlink related code into seperate file

[Marc Kleine-Budde <mkl@pengutronix.de>]

This patch moves the netlink related code of the CAN device infrastructure into
a separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-7-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/net/can/dev/Makefile  |   1 +
 drivers/net/can/dev/dev.c     | 370 +--------------------------------
 drivers/net/can/dev/netlink.c | 379 ++++++++++++++++++++++++++++++++++
 include/linux/can/dev.h       |   6 +
 4 files changed, 389 insertions(+), 367 deletions(-)
 create mode 100644 drivers/net/can/dev/netlink.c

diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile
index 188bd53b113c..3e2e207861fc 100644
--- a/drivers/net/can/dev/Makefile
+++ b/drivers/net/can/dev/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_CAN_DEV)		+= can-dev.o
 can-dev-y			+= bittiming.o
 can-dev-y			+= dev.o
 can-dev-y			+= length.o
+can-dev-y			+= netlink.o
 can-dev-y			+= rx-offload.o
 can-dev-y                       += skb.o
 
diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c
index fe71ff9ef8c9..f580f0ac6497 100644
--- a/drivers/net/can/dev/dev.c
+++ b/drivers/net/can/dev/dev.c
@@ -14,10 +14,8 @@
 #include <linux/can/can-ml.h>
 #include <linux/can/dev.h>
 #include <linux/can/skb.h>
-#include <linux/can/netlink.h>
 #include <linux/can/led.h>
 #include <linux/of.h>
-#include <net/rtnetlink.h>
 
 #define MOD_DESC "CAN device driver interface"
 
@@ -223,7 +221,7 @@ void can_bus_off(struct net_device *dev)
 }
 EXPORT_SYMBOL_GPL(can_bus_off);
 
-static void can_setup(struct net_device *dev)
+void can_setup(struct net_device *dev)
 {
 	dev->type = ARPHRD_CAN;
 	dev->mtu = CAN_MTU;
@@ -399,368 +397,6 @@ void close_candev(struct net_device *dev)
 }
 EXPORT_SYMBOL_GPL(close_candev);
 
-/* CAN netlink interface */
-static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
-	[IFLA_CAN_STATE]	= { .type = NLA_U32 },
-	[IFLA_CAN_CTRLMODE]	= { .len = sizeof(struct can_ctrlmode) },
-	[IFLA_CAN_RESTART_MS]	= { .type = NLA_U32 },
-	[IFLA_CAN_RESTART]	= { .type = NLA_U32 },
-	[IFLA_CAN_BITTIMING]	= { .len = sizeof(struct can_bittiming) },
-	[IFLA_CAN_BITTIMING_CONST]
-				= { .len = sizeof(struct can_bittiming_const) },
-	[IFLA_CAN_CLOCK]	= { .len = sizeof(struct can_clock) },
-	[IFLA_CAN_BERR_COUNTER]	= { .len = sizeof(struct can_berr_counter) },
-	[IFLA_CAN_DATA_BITTIMING]
-				= { .len = sizeof(struct can_bittiming) },
-	[IFLA_CAN_DATA_BITTIMING_CONST]
-				= { .len = sizeof(struct can_bittiming_const) },
-	[IFLA_CAN_TERMINATION]	= { .type = NLA_U16 },
-};
-
-static int can_validate(struct nlattr *tb[], struct nlattr *data[],
-			struct netlink_ext_ack *extack)
-{
-	bool is_can_fd = false;
-
-	/* Make sure that valid CAN FD configurations always consist of
-	 * - nominal/arbitration bittiming
-	 * - data bittiming
-	 * - control mode with CAN_CTRLMODE_FD set
-	 */
-
-	if (!data)
-		return 0;
-
-	if (data[IFLA_CAN_CTRLMODE]) {
-		struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
-
-		is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD;
-	}
-
-	if (is_can_fd) {
-		if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
-			return -EOPNOTSUPP;
-	}
-
-	if (data[IFLA_CAN_DATA_BITTIMING]) {
-		if (!is_can_fd || !data[IFLA_CAN_BITTIMING])
-			return -EOPNOTSUPP;
-	}
-
-	return 0;
-}
-
-static int can_changelink(struct net_device *dev, struct nlattr *tb[],
-			  struct nlattr *data[],
-			  struct netlink_ext_ack *extack)
-{
-	struct can_priv *priv = netdev_priv(dev);
-	int err;
-
-	/* We need synchronization with dev->stop() */
-	ASSERT_RTNL();
-
-	if (data[IFLA_CAN_BITTIMING]) {
-		struct can_bittiming bt;
-
-		/* Do not allow changing bittiming while running */
-		if (dev->flags & IFF_UP)
-			return -EBUSY;
-
-		/* Calculate bittiming parameters based on
-		 * bittiming_const if set, otherwise pass bitrate
-		 * directly via do_set_bitrate(). Bail out if neither
-		 * is given.
-		 */
-		if (!priv->bittiming_const && !priv->do_set_bittiming)
-			return -EOPNOTSUPP;
-
-		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
-		err = can_get_bittiming(dev, &bt,
-					priv->bittiming_const,
-					priv->bitrate_const,
-					priv->bitrate_const_cnt);
-		if (err)
-			return err;
-
-		if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) {
-			netdev_err(dev, "arbitration bitrate surpasses transceiver capabilities of %d bps\n",
-				   priv->bitrate_max);
-			return -EINVAL;
-		}
-
-		memcpy(&priv->bittiming, &bt, sizeof(bt));
-
-		if (priv->do_set_bittiming) {
-			/* Finally, set the bit-timing registers */
-			err = priv->do_set_bittiming(dev);
-			if (err)
-				return err;
-		}
-	}
-
-	if (data[IFLA_CAN_CTRLMODE]) {
-		struct can_ctrlmode *cm;
-		u32 ctrlstatic;
-		u32 maskedflags;
-
-		/* Do not allow changing controller mode while running */
-		if (dev->flags & IFF_UP)
-			return -EBUSY;
-		cm = nla_data(data[IFLA_CAN_CTRLMODE]);
-		ctrlstatic = priv->ctrlmode_static;
-		maskedflags = cm->flags & cm->mask;
-
-		/* check whether provided bits are allowed to be passed */
-		if (cm->mask & ~(priv->ctrlmode_supported | ctrlstatic))
-			return -EOPNOTSUPP;
-
-		/* do not check for static fd-non-iso if 'fd' is disabled */
-		if (!(maskedflags & CAN_CTRLMODE_FD))
-			ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
-
-		/* make sure static options are provided by configuration */
-		if ((maskedflags & ctrlstatic) != ctrlstatic)
-			return -EOPNOTSUPP;
-
-		/* clear bits to be modified and copy the flag values */
-		priv->ctrlmode &= ~cm->mask;
-		priv->ctrlmode |= maskedflags;
-
-		/* CAN_CTRLMODE_FD can only be set when driver supports FD */
-		if (priv->ctrlmode & CAN_CTRLMODE_FD)
-			dev->mtu = CANFD_MTU;
-		else
-			dev->mtu = CAN_MTU;
-	}
-
-	if (data[IFLA_CAN_RESTART_MS]) {
-		/* Do not allow changing restart delay while running */
-		if (dev->flags & IFF_UP)
-			return -EBUSY;
-		priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
-	}
-
-	if (data[IFLA_CAN_RESTART]) {
-		/* Do not allow a restart while not running */
-		if (!(dev->flags & IFF_UP))
-			return -EINVAL;
-		err = can_restart_now(dev);
-		if (err)
-			return err;
-	}
-
-	if (data[IFLA_CAN_DATA_BITTIMING]) {
-		struct can_bittiming dbt;
-
-		/* Do not allow changing bittiming while running */
-		if (dev->flags & IFF_UP)
-			return -EBUSY;
-
-		/* Calculate bittiming parameters based on
-		 * data_bittiming_const if set, otherwise pass bitrate
-		 * directly via do_set_bitrate(). Bail out if neither
-		 * is given.
-		 */
-		if (!priv->data_bittiming_const && !priv->do_set_data_bittiming)
-			return -EOPNOTSUPP;
-
-		memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
-		       sizeof(dbt));
-		err = can_get_bittiming(dev, &dbt,
-					priv->data_bittiming_const,
-					priv->data_bitrate_const,
-					priv->data_bitrate_const_cnt);
-		if (err)
-			return err;
-
-		if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
-			netdev_err(dev, "canfd data bitrate surpasses transceiver capabilities of %d bps\n",
-				   priv->bitrate_max);
-			return -EINVAL;
-		}
-
-		memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
-
-		if (priv->do_set_data_bittiming) {
-			/* Finally, set the bit-timing registers */
-			err = priv->do_set_data_bittiming(dev);
-			if (err)
-				return err;
-		}
-	}
-
-	if (data[IFLA_CAN_TERMINATION]) {
-		const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]);
-		const unsigned int num_term = priv->termination_const_cnt;
-		unsigned int i;
-
-		if (!priv->do_set_termination)
-			return -EOPNOTSUPP;
-
-		/* check whether given value is supported by the interface */
-		for (i = 0; i < num_term; i++) {
-			if (termval == priv->termination_const[i])
-				break;
-		}
-		if (i >= num_term)
-			return -EINVAL;
-
-		/* Finally, set the termination value */
-		err = priv->do_set_termination(dev, termval);
-		if (err)
-			return err;
-
-		priv->termination = termval;
-	}
-
-	return 0;
-}
-
-static size_t can_get_size(const struct net_device *dev)
-{
-	struct can_priv *priv = netdev_priv(dev);
-	size_t size = 0;
-
-	if (priv->bittiming.bitrate)				/* IFLA_CAN_BITTIMING */
-		size += nla_total_size(sizeof(struct can_bittiming));
-	if (priv->bittiming_const)				/* IFLA_CAN_BITTIMING_CONST */
-		size += nla_total_size(sizeof(struct can_bittiming_const));
-	size += nla_total_size(sizeof(struct can_clock));	/* IFLA_CAN_CLOCK */
-	size += nla_total_size(sizeof(u32));			/* IFLA_CAN_STATE */
-	size += nla_total_size(sizeof(struct can_ctrlmode));	/* IFLA_CAN_CTRLMODE */
-	size += nla_total_size(sizeof(u32));			/* IFLA_CAN_RESTART_MS */
-	if (priv->do_get_berr_counter)				/* IFLA_CAN_BERR_COUNTER */
-		size += nla_total_size(sizeof(struct can_berr_counter));
-	if (priv->data_bittiming.bitrate)			/* IFLA_CAN_DATA_BITTIMING */
-		size += nla_total_size(sizeof(struct can_bittiming));
-	if (priv->data_bittiming_const)				/* IFLA_CAN_DATA_BITTIMING_CONST */
-		size += nla_total_size(sizeof(struct can_bittiming_const));
-	if (priv->termination_const) {
-		size += nla_total_size(sizeof(priv->termination));		/* IFLA_CAN_TERMINATION */
-		size += nla_total_size(sizeof(*priv->termination_const) *	/* IFLA_CAN_TERMINATION_CONST */
-				       priv->termination_const_cnt);
-	}
-	if (priv->bitrate_const)				/* IFLA_CAN_BITRATE_CONST */
-		size += nla_total_size(sizeof(*priv->bitrate_const) *
-				       priv->bitrate_const_cnt);
-	if (priv->data_bitrate_const)				/* IFLA_CAN_DATA_BITRATE_CONST */
-		size += nla_total_size(sizeof(*priv->data_bitrate_const) *
-				       priv->data_bitrate_const_cnt);
-	size += sizeof(priv->bitrate_max);			/* IFLA_CAN_BITRATE_MAX */
-
-	return size;
-}
-
-static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
-{
-	struct can_priv *priv = netdev_priv(dev);
-	struct can_ctrlmode cm = {.flags = priv->ctrlmode};
-	struct can_berr_counter bec;
-	enum can_state state = priv->state;
-
-	if (priv->do_get_state)
-		priv->do_get_state(dev, &state);
-
-	if ((priv->bittiming.bitrate &&
-	     nla_put(skb, IFLA_CAN_BITTIMING,
-		     sizeof(priv->bittiming), &priv->bittiming)) ||
-
-	    (priv->bittiming_const &&
-	     nla_put(skb, IFLA_CAN_BITTIMING_CONST,
-		     sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
-
-	    nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) ||
-	    nla_put_u32(skb, IFLA_CAN_STATE, state) ||
-	    nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
-	    nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
-
-	    (priv->do_get_berr_counter &&
-	     !priv->do_get_berr_counter(dev, &bec) &&
-	     nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
-
-	    (priv->data_bittiming.bitrate &&
-	     nla_put(skb, IFLA_CAN_DATA_BITTIMING,
-		     sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
-
-	    (priv->data_bittiming_const &&
-	     nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
-		     sizeof(*priv->data_bittiming_const),
-		     priv->data_bittiming_const)) ||
-
-	    (priv->termination_const &&
-	     (nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) ||
-	      nla_put(skb, IFLA_CAN_TERMINATION_CONST,
-		      sizeof(*priv->termination_const) *
-		      priv->termination_const_cnt,
-		      priv->termination_const))) ||
-
-	    (priv->bitrate_const &&
-	     nla_put(skb, IFLA_CAN_BITRATE_CONST,
-		     sizeof(*priv->bitrate_const) *
-		     priv->bitrate_const_cnt,
-		     priv->bitrate_const)) ||
-
-	    (priv->data_bitrate_const &&
-	     nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST,
-		     sizeof(*priv->data_bitrate_const) *
-		     priv->data_bitrate_const_cnt,
-		     priv->data_bitrate_const)) ||
-
-	    (nla_put(skb, IFLA_CAN_BITRATE_MAX,
-		     sizeof(priv->bitrate_max),
-		     &priv->bitrate_max))
-	    )
-
-		return -EMSGSIZE;
-
-	return 0;
-}
-
-static size_t can_get_xstats_size(const struct net_device *dev)
-{
-	return sizeof(struct can_device_stats);
-}
-
-static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
-{
-	struct can_priv *priv = netdev_priv(dev);
-
-	if (nla_put(skb, IFLA_INFO_XSTATS,
-		    sizeof(priv->can_stats), &priv->can_stats))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
-}
-
-static int can_newlink(struct net *src_net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[],
-		       struct netlink_ext_ack *extack)
-{
-	return -EOPNOTSUPP;
-}
-
-static void can_dellink(struct net_device *dev, struct list_head *head)
-{
-}
-
-static struct rtnl_link_ops can_link_ops __read_mostly = {
-	.kind		= "can",
-	.maxtype	= IFLA_CAN_MAX,
-	.policy		= can_policy,
-	.setup		= can_setup,
-	.validate	= can_validate,
-	.newlink	= can_newlink,
-	.changelink	= can_changelink,
-	.dellink	= can_dellink,
-	.get_size	= can_get_size,
-	.fill_info	= can_fill_info,
-	.get_xstats_size = can_get_xstats_size,
-	.fill_xstats	= can_fill_xstats,
-};
-
 /* Register the CAN network device */
 int register_candev(struct net_device *dev)
 {
@@ -812,7 +448,7 @@ static __init int can_dev_init(void)
 
 	can_led_notifier_init();
 
-	err = rtnl_link_register(&can_link_ops);
+	err = can_netlink_register();
 	if (!err)
 		pr_info(MOD_DESC "\n");
 
@@ -822,7 +458,7 @@ module_init(can_dev_init);
 
 static __exit void can_dev_exit(void)
 {
-	rtnl_link_unregister(&can_link_ops);
+	can_netlink_unregister();
 
 	can_led_notifier_exit();
 }
diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
new file mode 100644
index 000000000000..3ae884cdf677
--- /dev/null
+++ b/drivers/net/can/dev/netlink.c
@@ -0,0 +1,379 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
+ * Copyright (C) 2006 Andrey Volkov, Varma Electronics
+ * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
+ */
+
+#include <linux/can/dev.h>
+#include <net/rtnetlink.h>
+
+static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
+	[IFLA_CAN_STATE]	= { .type = NLA_U32 },
+	[IFLA_CAN_CTRLMODE]	= { .len = sizeof(struct can_ctrlmode) },
+	[IFLA_CAN_RESTART_MS]	= { .type = NLA_U32 },
+	[IFLA_CAN_RESTART]	= { .type = NLA_U32 },
+	[IFLA_CAN_BITTIMING]	= { .len = sizeof(struct can_bittiming) },
+	[IFLA_CAN_BITTIMING_CONST]
+				= { .len = sizeof(struct can_bittiming_const) },
+	[IFLA_CAN_CLOCK]	= { .len = sizeof(struct can_clock) },
+	[IFLA_CAN_BERR_COUNTER]	= { .len = sizeof(struct can_berr_counter) },
+	[IFLA_CAN_DATA_BITTIMING]
+				= { .len = sizeof(struct can_bittiming) },
+	[IFLA_CAN_DATA_BITTIMING_CONST]
+				= { .len = sizeof(struct can_bittiming_const) },
+	[IFLA_CAN_TERMINATION]	= { .type = NLA_U16 },
+};
+
+static int can_validate(struct nlattr *tb[], struct nlattr *data[],
+			struct netlink_ext_ack *extack)
+{
+	bool is_can_fd = false;
+
+	/* Make sure that valid CAN FD configurations always consist of
+	 * - nominal/arbitration bittiming
+	 * - data bittiming
+	 * - control mode with CAN_CTRLMODE_FD set
+	 */
+
+	if (!data)
+		return 0;
+
+	if (data[IFLA_CAN_CTRLMODE]) {
+		struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
+
+		is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD;
+	}
+
+	if (is_can_fd) {
+		if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
+			return -EOPNOTSUPP;
+	}
+
+	if (data[IFLA_CAN_DATA_BITTIMING]) {
+		if (!is_can_fd || !data[IFLA_CAN_BITTIMING])
+			return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int can_changelink(struct net_device *dev, struct nlattr *tb[],
+			  struct nlattr *data[],
+			  struct netlink_ext_ack *extack)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	int err;
+
+	/* We need synchronization with dev->stop() */
+	ASSERT_RTNL();
+
+	if (data[IFLA_CAN_BITTIMING]) {
+		struct can_bittiming bt;
+
+		/* Do not allow changing bittiming while running */
+		if (dev->flags & IFF_UP)
+			return -EBUSY;
+
+		/* Calculate bittiming parameters based on
+		 * bittiming_const if set, otherwise pass bitrate
+		 * directly via do_set_bitrate(). Bail out if neither
+		 * is given.
+		 */
+		if (!priv->bittiming_const && !priv->do_set_bittiming)
+			return -EOPNOTSUPP;
+
+		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
+		err = can_get_bittiming(dev, &bt,
+					priv->bittiming_const,
+					priv->bitrate_const,
+					priv->bitrate_const_cnt);
+		if (err)
+			return err;
+
+		if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) {
+			netdev_err(dev, "arbitration bitrate surpasses transceiver capabilities of %d bps\n",
+				   priv->bitrate_max);
+			return -EINVAL;
+		}
+
+		memcpy(&priv->bittiming, &bt, sizeof(bt));
+
+		if (priv->do_set_bittiming) {
+			/* Finally, set the bit-timing registers */
+			err = priv->do_set_bittiming(dev);
+			if (err)
+				return err;
+		}
+	}
+
+	if (data[IFLA_CAN_CTRLMODE]) {
+		struct can_ctrlmode *cm;
+		u32 ctrlstatic;
+		u32 maskedflags;
+
+		/* Do not allow changing controller mode while running */
+		if (dev->flags & IFF_UP)
+			return -EBUSY;
+		cm = nla_data(data[IFLA_CAN_CTRLMODE]);
+		ctrlstatic = priv->ctrlmode_static;
+		maskedflags = cm->flags & cm->mask;
+
+		/* check whether provided bits are allowed to be passed */
+		if (cm->mask & ~(priv->ctrlmode_supported | ctrlstatic))
+			return -EOPNOTSUPP;
+
+		/* do not check for static fd-non-iso if 'fd' is disabled */
+		if (!(maskedflags & CAN_CTRLMODE_FD))
+			ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
+
+		/* make sure static options are provided by configuration */
+		if ((maskedflags & ctrlstatic) != ctrlstatic)
+			return -EOPNOTSUPP;
+
+		/* clear bits to be modified and copy the flag values */
+		priv->ctrlmode &= ~cm->mask;
+		priv->ctrlmode |= maskedflags;
+
+		/* CAN_CTRLMODE_FD can only be set when driver supports FD */
+		if (priv->ctrlmode & CAN_CTRLMODE_FD)
+			dev->mtu = CANFD_MTU;
+		else
+			dev->mtu = CAN_MTU;
+	}
+
+	if (data[IFLA_CAN_RESTART_MS]) {
+		/* Do not allow changing restart delay while running */
+		if (dev->flags & IFF_UP)
+			return -EBUSY;
+		priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
+	}
+
+	if (data[IFLA_CAN_RESTART]) {
+		/* Do not allow a restart while not running */
+		if (!(dev->flags & IFF_UP))
+			return -EINVAL;
+		err = can_restart_now(dev);
+		if (err)
+			return err;
+	}
+
+	if (data[IFLA_CAN_DATA_BITTIMING]) {
+		struct can_bittiming dbt;
+
+		/* Do not allow changing bittiming while running */
+		if (dev->flags & IFF_UP)
+			return -EBUSY;
+
+		/* Calculate bittiming parameters based on
+		 * data_bittiming_const if set, otherwise pass bitrate
+		 * directly via do_set_bitrate(). Bail out if neither
+		 * is given.
+		 */
+		if (!priv->data_bittiming_const && !priv->do_set_data_bittiming)
+			return -EOPNOTSUPP;
+
+		memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
+		       sizeof(dbt));
+		err = can_get_bittiming(dev, &dbt,
+					priv->data_bittiming_const,
+					priv->data_bitrate_const,
+					priv->data_bitrate_const_cnt);
+		if (err)
+			return err;
+
+		if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
+			netdev_err(dev, "canfd data bitrate surpasses transceiver capabilities of %d bps\n",
+				   priv->bitrate_max);
+			return -EINVAL;
+		}
+
+		memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
+
+		if (priv->do_set_data_bittiming) {
+			/* Finally, set the bit-timing registers */
+			err = priv->do_set_data_bittiming(dev);
+			if (err)
+				return err;
+		}
+	}
+
+	if (data[IFLA_CAN_TERMINATION]) {
+		const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]);
+		const unsigned int num_term = priv->termination_const_cnt;
+		unsigned int i;
+
+		if (!priv->do_set_termination)
+			return -EOPNOTSUPP;
+
+		/* check whether given value is supported by the interface */
+		for (i = 0; i < num_term; i++) {
+			if (termval == priv->termination_const[i])
+				break;
+		}
+		if (i >= num_term)
+			return -EINVAL;
+
+		/* Finally, set the termination value */
+		err = priv->do_set_termination(dev, termval);
+		if (err)
+			return err;
+
+		priv->termination = termval;
+	}
+
+	return 0;
+}
+
+static size_t can_get_size(const struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	size_t size = 0;
+
+	if (priv->bittiming.bitrate)				/* IFLA_CAN_BITTIMING */
+		size += nla_total_size(sizeof(struct can_bittiming));
+	if (priv->bittiming_const)				/* IFLA_CAN_BITTIMING_CONST */
+		size += nla_total_size(sizeof(struct can_bittiming_const));
+	size += nla_total_size(sizeof(struct can_clock));	/* IFLA_CAN_CLOCK */
+	size += nla_total_size(sizeof(u32));			/* IFLA_CAN_STATE */
+	size += nla_total_size(sizeof(struct can_ctrlmode));	/* IFLA_CAN_CTRLMODE */
+	size += nla_total_size(sizeof(u32));			/* IFLA_CAN_RESTART_MS */
+	if (priv->do_get_berr_counter)				/* IFLA_CAN_BERR_COUNTER */
+		size += nla_total_size(sizeof(struct can_berr_counter));
+	if (priv->data_bittiming.bitrate)			/* IFLA_CAN_DATA_BITTIMING */
+		size += nla_total_size(sizeof(struct can_bittiming));
+	if (priv->data_bittiming_const)				/* IFLA_CAN_DATA_BITTIMING_CONST */
+		size += nla_total_size(sizeof(struct can_bittiming_const));
+	if (priv->termination_const) {
+		size += nla_total_size(sizeof(priv->termination));		/* IFLA_CAN_TERMINATION */
+		size += nla_total_size(sizeof(*priv->termination_const) *	/* IFLA_CAN_TERMINATION_CONST */
+				       priv->termination_const_cnt);
+	}
+	if (priv->bitrate_const)				/* IFLA_CAN_BITRATE_CONST */
+		size += nla_total_size(sizeof(*priv->bitrate_const) *
+				       priv->bitrate_const_cnt);
+	if (priv->data_bitrate_const)				/* IFLA_CAN_DATA_BITRATE_CONST */
+		size += nla_total_size(sizeof(*priv->data_bitrate_const) *
+				       priv->data_bitrate_const_cnt);
+	size += sizeof(priv->bitrate_max);			/* IFLA_CAN_BITRATE_MAX */
+
+	return size;
+}
+
+static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	struct can_ctrlmode cm = {.flags = priv->ctrlmode};
+	struct can_berr_counter bec;
+	enum can_state state = priv->state;
+
+	if (priv->do_get_state)
+		priv->do_get_state(dev, &state);
+
+	if ((priv->bittiming.bitrate &&
+	     nla_put(skb, IFLA_CAN_BITTIMING,
+		     sizeof(priv->bittiming), &priv->bittiming)) ||
+
+	    (priv->bittiming_const &&
+	     nla_put(skb, IFLA_CAN_BITTIMING_CONST,
+		     sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
+
+	    nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) ||
+	    nla_put_u32(skb, IFLA_CAN_STATE, state) ||
+	    nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
+	    nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
+
+	    (priv->do_get_berr_counter &&
+	     !priv->do_get_berr_counter(dev, &bec) &&
+	     nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
+
+	    (priv->data_bittiming.bitrate &&
+	     nla_put(skb, IFLA_CAN_DATA_BITTIMING,
+		     sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
+
+	    (priv->data_bittiming_const &&
+	     nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
+		     sizeof(*priv->data_bittiming_const),
+		     priv->data_bittiming_const)) ||
+
+	    (priv->termination_const &&
+	     (nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) ||
+	      nla_put(skb, IFLA_CAN_TERMINATION_CONST,
+		      sizeof(*priv->termination_const) *
+		      priv->termination_const_cnt,
+		      priv->termination_const))) ||
+
+	    (priv->bitrate_const &&
+	     nla_put(skb, IFLA_CAN_BITRATE_CONST,
+		     sizeof(*priv->bitrate_const) *
+		     priv->bitrate_const_cnt,
+		     priv->bitrate_const)) ||
+
+	    (priv->data_bitrate_const &&
+	     nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST,
+		     sizeof(*priv->data_bitrate_const) *
+		     priv->data_bitrate_const_cnt,
+		     priv->data_bitrate_const)) ||
+
+	    (nla_put(skb, IFLA_CAN_BITRATE_MAX,
+		     sizeof(priv->bitrate_max),
+		     &priv->bitrate_max))
+	    )
+
+		return -EMSGSIZE;
+
+	return 0;
+}
+
+static size_t can_get_xstats_size(const struct net_device *dev)
+{
+	return sizeof(struct can_device_stats);
+}
+
+static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	if (nla_put(skb, IFLA_INFO_XSTATS,
+		    sizeof(priv->can_stats), &priv->can_stats))
+		goto nla_put_failure;
+	return 0;
+
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
+static int can_newlink(struct net *src_net, struct net_device *dev,
+		       struct nlattr *tb[], struct nlattr *data[],
+		       struct netlink_ext_ack *extack)
+{
+	return -EOPNOTSUPP;
+}
+
+static void can_dellink(struct net_device *dev, struct list_head *head)
+{
+}
+
+struct rtnl_link_ops can_link_ops __read_mostly = {
+	.kind		= "can",
+	.maxtype	= IFLA_CAN_MAX,
+	.policy		= can_policy,
+	.setup		= can_setup,
+	.validate	= can_validate,
+	.newlink	= can_newlink,
+	.changelink	= can_changelink,
+	.dellink	= can_dellink,
+	.get_size	= can_get_size,
+	.fill_info	= can_fill_info,
+	.get_xstats_size = can_get_xstats_size,
+	.fill_xstats	= can_fill_xstats,
+};
+
+int can_netlink_register(void)
+{
+	return rtnl_link_register(&can_link_ops);
+}
+
+void can_netlink_unregister(void)
+{
+	rtnl_link_unregister(&can_link_ops);
+}
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index 4a26e128af7f..7faf6a37d5b2 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -100,6 +100,8 @@ static inline void can_set_static_ctrlmode(struct net_device *dev,
 		dev->mtu = CANFD_MTU;
 }
 
+void can_setup(struct net_device *dev);
+
 struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
 				    unsigned int txqs, unsigned int rxqs);
 #define alloc_candev(sizeof_priv, echo_skb_max) \
@@ -130,4 +132,8 @@ void of_can_transceiver(struct net_device *dev);
 static inline void of_can_transceiver(struct net_device *dev) { }
 #endif
 
+extern struct rtnl_link_ops can_link_ops;
+int can_netlink_register(void);
+void can_netlink_unregister(void);
+
 #endif /* !_CAN_DEV_H */
-- 
2.29.2