Merge tag 'linux-can-next-for-5.4-20190904' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2019-09-04 j1939

this is a pull request for net-next/master consisting of 21 patches.

the first 12 patches are by me and target the CAN core infrastructure.
They clean up the names of variables , structs and struct members,
convert can_rx_register() to use max() instead of open coding it and
remove unneeded code from the can_pernet_exit() callback.

The next three patches are also by me and they introduce and make use of
the CAN midlayer private structure. It is used to hold protocol specific
per device data structures.

The next patch is by Oleksij Rempel, switches the
&net->can.rcvlists_lock from a spin_lock() to a spin_lock_bh(), so that
it can be used from NAPI (soft IRQ) context.

The next 4 patches are by Kurt Van Dijck, he first updates his email
address via mailmap and then extends sockaddr_can to include j1939
members.

The final patch is the collective effort of many entities (The j1939
authors: Oliver Hartkopp, Bastian Stender, Elenita Hinds, kbuild test
robot, Kurt Van Dijck, Maxime Jayat, Robin van der Gracht, Oleksij
Rempel, Marc Kleine-Budde). It adds support of SAE J1939 protocol to the
CAN networking stack.

SAE J1939 is the vehicle bus recommended practice used for communication
and diagnostics among vehicle components. Originating in the car and
heavy-duty truck industry in the United States, it is now widely used in
other parts of the world.

P.S.: This pull request doesn't invalidate my last pull request:
      "pull-request: can-next 2019-09-03".
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 403 insertions, 0 deletions

diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c
new file mode 100644
index 000000000000..def2f813ffce
--- /dev/null
+++ b/net/can/j1939/main.c
@@ -0,0 +1,403 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2010-2011 EIA Electronics,
+//                         Pieter Beyens <pieter.beyens@eia.be>
+// Copyright (c) 2010-2011 EIA Electronics,
+//                         Kurt Van Dijck <kurt.van.dijck@eia.be>
+// Copyright (c) 2018 Protonic,
+//                         Robin van der Gracht <robin@protonic.nl>
+// Copyright (c) 2017-2019 Pengutronix,
+//                         Marc Kleine-Budde <kernel@pengutronix.de>
+// Copyright (c) 2017-2019 Pengutronix,
+//                         Oleksij Rempel <kernel@pengutronix.de>
+
+/* Core of can-j1939 that links j1939 to CAN. */
+
+#include <linux/can/can-ml.h>
+#include <linux/can/core.h>
+#include <linux/can/skb.h>
+#include <linux/if_arp.h>
+#include <linux/module.h>
+
+#include "j1939-priv.h"
+
+MODULE_DESCRIPTION("PF_CAN SAE J1939");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("EIA Electronics (Kurt Van Dijck & Pieter Beyens)");
+MODULE_ALIAS("can-proto-" __stringify(CAN_J1939));
+
+/* LOWLEVEL CAN interface */
+
+/* CAN_HDR: #bytes before can_frame data part */
+#define J1939_CAN_HDR (offsetof(struct can_frame, data))
+
+/* CAN_FTR: #bytes beyond data part */
+#define J1939_CAN_FTR (sizeof(struct can_frame) - J1939_CAN_HDR - \
+		 sizeof(((struct can_frame *)0)->data))
+
+/* lowest layer */
+static void j1939_can_recv(struct sk_buff *iskb, void *data)
+{
+	struct j1939_priv *priv = data;
+	struct sk_buff *skb;
+	struct j1939_sk_buff_cb *skcb, *iskcb;
+	struct can_frame *cf;
+
+	/* create a copy of the skb
+	 * j1939 only delivers the real data bytes,
+	 * the header goes into sockaddr.
+	 * j1939 may not touch the incoming skb in such way
+	 */
+	skb = skb_clone(iskb, GFP_ATOMIC);
+	if (!skb)
+		return;
+
+	can_skb_set_owner(skb, iskb->sk);
+
+	/* get a pointer to the header of the skb
+	 * the skb payload (pointer) is moved, so that the next skb_data
+	 * returns the actual payload
+	 */
+	cf = (void *)skb->data;
+	skb_pull(skb, J1939_CAN_HDR);
+
+	/* fix length, set to dlc, with 8 maximum */
+	skb_trim(skb, min_t(uint8_t, cf->can_dlc, 8));
+
+	/* set addr */
+	skcb = j1939_skb_to_cb(skb);
+	memset(skcb, 0, sizeof(*skcb));
+
+	iskcb = j1939_skb_to_cb(iskb);
+	skcb->tskey = iskcb->tskey;
+	skcb->priority = (cf->can_id >> 26) & 0x7;
+	skcb->addr.sa = cf->can_id;
+	skcb->addr.pgn = (cf->can_id >> 8) & J1939_PGN_MAX;
+	/* set default message type */
+	skcb->addr.type = J1939_TP;
+	if (j1939_pgn_is_pdu1(skcb->addr.pgn)) {
+		/* Type 1: with destination address */
+		skcb->addr.da = skcb->addr.pgn;
+		/* normalize pgn: strip dst address */
+		skcb->addr.pgn &= 0x3ff00;
+	} else {
+		/* set broadcast address */
+		skcb->addr.da = J1939_NO_ADDR;
+	}
+
+	/* update localflags */
+	read_lock_bh(&priv->lock);
+	if (j1939_address_is_unicast(skcb->addr.sa) &&
+	    priv->ents[skcb->addr.sa].nusers)
+		skcb->flags |= J1939_ECU_LOCAL_SRC;
+	if (j1939_address_is_unicast(skcb->addr.da) &&
+	    priv->ents[skcb->addr.da].nusers)
+		skcb->flags |= J1939_ECU_LOCAL_DST;
+	read_unlock_bh(&priv->lock);
+
+	/* deliver into the j1939 stack ... */
+	j1939_ac_recv(priv, skb);
+
+	if (j1939_tp_recv(priv, skb))
+		/* this means the transport layer processed the message */
+		goto done;
+
+	j1939_simple_recv(priv, skb);
+	j1939_sk_recv(priv, skb);
+ done:
+	kfree_skb(skb);
+}
+
+/* NETDEV MANAGEMENT */
+
+/* values for can_rx_(un)register */
+#define J1939_CAN_ID CAN_EFF_FLAG
+#define J1939_CAN_MASK (CAN_EFF_FLAG | CAN_RTR_FLAG)
+
+static DEFINE_SPINLOCK(j1939_netdev_lock);
+
+static struct j1939_priv *j1939_priv_create(struct net_device *ndev)
+{
+	struct j1939_priv *priv;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return NULL;
+
+	rwlock_init(&priv->lock);
+	INIT_LIST_HEAD(&priv->ecus);
+	priv->ndev = ndev;
+	kref_init(&priv->kref);
+	kref_init(&priv->rx_kref);
+	dev_hold(ndev);
+
+	netdev_dbg(priv->ndev, "%s : 0x%p\n", __func__, priv);
+
+	return priv;
+}
+
+static inline void j1939_priv_set(struct net_device *ndev,
+				  struct j1939_priv *priv)
+{
+	struct can_ml_priv *can_ml_priv = ndev->ml_priv;
+
+	can_ml_priv->j1939_priv = priv;
+}
+
+static void __j1939_priv_release(struct kref *kref)
+{
+	struct j1939_priv *priv = container_of(kref, struct j1939_priv, kref);
+	struct net_device *ndev = priv->ndev;
+
+	netdev_dbg(priv->ndev, "%s: 0x%p\n", __func__, priv);
+
+	dev_put(ndev);
+	kfree(priv);
+}
+
+void j1939_priv_put(struct j1939_priv *priv)
+{
+	kref_put(&priv->kref, __j1939_priv_release);
+}
+
+void j1939_priv_get(struct j1939_priv *priv)
+{
+	kref_get(&priv->kref);
+}
+
+static int j1939_can_rx_register(struct j1939_priv *priv)
+{
+	struct net_device *ndev = priv->ndev;
+	int ret;
+
+	j1939_priv_get(priv);
+	ret = can_rx_register(dev_net(ndev), ndev, J1939_CAN_ID, J1939_CAN_MASK,
+			      j1939_can_recv, priv, "j1939", NULL);
+	if (ret < 0) {
+		j1939_priv_put(priv);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void j1939_can_rx_unregister(struct j1939_priv *priv)
+{
+	struct net_device *ndev = priv->ndev;
+
+	can_rx_unregister(dev_net(ndev), ndev, J1939_CAN_ID, J1939_CAN_MASK,
+			  j1939_can_recv, priv);
+
+	j1939_priv_put(priv);
+}
+
+static void __j1939_rx_release(struct kref *kref)
+	__releases(&j1939_netdev_lock)
+{
+	struct j1939_priv *priv = container_of(kref, struct j1939_priv,
+					       rx_kref);
+
+	j1939_can_rx_unregister(priv);
+	j1939_ecu_unmap_all(priv);
+	j1939_priv_set(priv->ndev, NULL);
+	spin_unlock(&j1939_netdev_lock);
+}
+
+/* get pointer to priv without increasing ref counter */
+static inline struct j1939_priv *j1939_ndev_to_priv(struct net_device *ndev)
+{
+	struct can_ml_priv *can_ml_priv = ndev->ml_priv;
+
+	return can_ml_priv->j1939_priv;
+}
+
+static struct j1939_priv *j1939_priv_get_by_ndev_locked(struct net_device *ndev)
+{
+	struct j1939_priv *priv;
+
+	lockdep_assert_held(&j1939_netdev_lock);
+
+	if (ndev->type != ARPHRD_CAN)
+		return NULL;
+
+	priv = j1939_ndev_to_priv(ndev);
+	if (priv)
+		j1939_priv_get(priv);
+
+	return priv;
+}
+
+static struct j1939_priv *j1939_priv_get_by_ndev(struct net_device *ndev)
+{
+	struct j1939_priv *priv;
+
+	spin_lock(&j1939_netdev_lock);
+	priv = j1939_priv_get_by_ndev_locked(ndev);
+	spin_unlock(&j1939_netdev_lock);
+
+	return priv;
+}
+
+struct j1939_priv *j1939_netdev_start(struct net_device *ndev)
+{
+	struct j1939_priv *priv, *priv_new;
+	int ret;
+
+	priv = j1939_priv_get_by_ndev(ndev);
+	if (priv) {
+		kref_get(&priv->rx_kref);
+		return priv;
+	}
+
+	priv = j1939_priv_create(ndev);
+	if (!priv)
+		return ERR_PTR(-ENOMEM);
+
+	j1939_tp_init(priv);
+	spin_lock_init(&priv->j1939_socks_lock);
+	INIT_LIST_HEAD(&priv->j1939_socks);
+
+	spin_lock(&j1939_netdev_lock);
+	priv_new = j1939_priv_get_by_ndev_locked(ndev);
+	if (priv_new) {
+		/* Someone was faster than us, use their priv and roll
+		 * back our's.
+		 */
+		spin_unlock(&j1939_netdev_lock);
+		dev_put(ndev);
+		kfree(priv);
+		kref_get(&priv_new->rx_kref);
+		return priv_new;
+	}
+	j1939_priv_set(ndev, priv);
+	spin_unlock(&j1939_netdev_lock);
+
+	ret = j1939_can_rx_register(priv);
+	if (ret < 0)
+		goto out_priv_put;
+
+	return priv;
+
+ out_priv_put:
+	j1939_priv_set(ndev, NULL);
+	dev_put(ndev);
+	kfree(priv);
+
+	return ERR_PTR(ret);
+}
+
+void j1939_netdev_stop(struct j1939_priv *priv)
+{
+	kref_put_lock(&priv->rx_kref, __j1939_rx_release, &j1939_netdev_lock);
+	j1939_priv_put(priv);
+}
+
+int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb)
+{
+	int ret, dlc;
+	canid_t canid;
+	struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb);
+	struct can_frame *cf;
+
+	/* apply sanity checks */
+	if (j1939_pgn_is_pdu1(skcb->addr.pgn))
+		skcb->addr.pgn &= J1939_PGN_PDU1_MAX;
+	else
+		skcb->addr.pgn &= J1939_PGN_MAX;
+
+	if (skcb->priority > 7)
+		skcb->priority = 6;
+
+	ret = j1939_ac_fixup(priv, skb);
+	if (unlikely(ret))
+		goto failed;
+	dlc = skb->len;
+
+	/* re-claim the CAN_HDR from the SKB */
+	cf = skb_push(skb, J1939_CAN_HDR);
+
+	/* make it a full can frame again */
+	skb_put(skb, J1939_CAN_FTR + (8 - dlc));
+
+	canid = CAN_EFF_FLAG |
+		(skcb->priority << 26) |
+		(skcb->addr.pgn << 8) |
+		skcb->addr.sa;
+	if (j1939_pgn_is_pdu1(skcb->addr.pgn))
+		canid |= skcb->addr.da << 8;
+
+	cf->can_id = canid;
+	cf->can_dlc = dlc;
+
+	return can_send(skb, 1);
+
+ failed:
+	kfree_skb(skb);
+	return ret;
+}
+
+static int j1939_netdev_notify(struct notifier_block *nb,
+			       unsigned long msg, void *data)
+{
+	struct net_device *ndev = netdev_notifier_info_to_dev(data);
+	struct j1939_priv *priv;
+
+	priv = j1939_priv_get_by_ndev(ndev);
+	if (!priv)
+		goto notify_done;
+
+	if (ndev->type != ARPHRD_CAN)
+		goto notify_put;
+
+	switch (msg) {
+	case NETDEV_DOWN:
+		j1939_cancel_active_session(priv, NULL);
+		j1939_sk_netdev_event_netdown(priv);
+		j1939_ecu_unmap_all(priv);
+		break;
+	}
+
+notify_put:
+	j1939_priv_put(priv);
+
+notify_done:
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block j1939_netdev_notifier = {
+	.notifier_call = j1939_netdev_notify,
+};
+
+/* MODULE interface */
+static __init int j1939_module_init(void)
+{
+	int ret;
+
+	pr_info("can: SAE J1939\n");
+
+	ret = register_netdevice_notifier(&j1939_netdev_notifier);
+	if (ret)
+		goto fail_notifier;
+
+	ret = can_proto_register(&j1939_can_proto);
+	if (ret < 0) {
+		pr_err("can: registration of j1939 protocol failed\n");
+		goto fail_sk;
+	}
+
+	return 0;
+
+ fail_sk:
+	unregister_netdevice_notifier(&j1939_netdev_notifier);
+ fail_notifier:
+	return ret;
+}
+
+static __exit void j1939_module_exit(void)
+{
+	can_proto_unregister(&j1939_can_proto);
+
+	unregister_netdevice_notifier(&j1939_netdev_notifier);
+}
+
+module_init(j1939_module_init);
+module_exit(j1939_module_exit);