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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-18 12:34:53 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-18 12:34:53 -0700
commit81160dda9a7aad13c04e78bb2cfd3c4630e3afab (patch)
tree4bf79ffa9fc7dc5e2915ff978778c3402c491113 /net/can/j1939/main.c
parentMerge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 (diff)
parentMerge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net (diff)
downloadlinux-dev-81160dda9a7aad13c04e78bb2cfd3c4630e3afab.tar.xz
linux-dev-81160dda9a7aad13c04e78bb2cfd3c4630e3afab.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller: 1) Support IPV6 RA Captive Portal Identifier, from Maciej Żenczykowski. 2) Use bio_vec in the networking instead of custom skb_frag_t, from Matthew Wilcox. 3) Make use of xmit_more in r8169 driver, from Heiner Kallweit. 4) Add devmap_hash to xdp, from Toke Høiland-Jørgensen. 5) Support all variants of 5750X bnxt_en chips, from Michael Chan. 6) More RTNL avoidance work in the core and mlx5 driver, from Vlad Buslov. 7) Add TCP syn cookies bpf helper, from Petar Penkov. 8) Add 'nettest' to selftests and use it, from David Ahern. 9) Add extack support to drop_monitor, add packet alert mode and support for HW drops, from Ido Schimmel. 10) Add VLAN offload to stmmac, from Jose Abreu. 11) Lots of devm_platform_ioremap_resource() conversions, from YueHaibing. 12) Add IONIC driver, from Shannon Nelson. 13) Several kTLS cleanups, from Jakub Kicinski. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1930 commits) mlxsw: spectrum_buffers: Add the ability to query the CPU port's shared buffer mlxsw: spectrum: Register CPU port with devlink mlxsw: spectrum_buffers: Prevent changing CPU port's configuration net: ena: fix incorrect update of intr_delay_resolution net: ena: fix retrieval of nonadaptive interrupt moderation intervals net: ena: fix update of interrupt moderation register net: ena: remove all old adaptive rx interrupt moderation code from ena_com net: ena: remove ena_restore_ethtool_params() and relevant fields net: ena: remove old adaptive interrupt moderation code from ena_netdev net: ena: remove code duplication in ena_com_update_nonadaptive_moderation_interval _*() net: ena: enable the interrupt_moderation in driver_supported_features net: ena: reimplement set/get_coalesce() net: ena: switch to dim algorithm for rx adaptive interrupt moderation net: ena: add intr_moder_rx_interval to struct ena_com_dev and use it net: phy: adin: implement Energy Detect Powerdown mode via phy-tunable ethtool: implement Energy Detect Powerdown support via phy-tunable xen-netfront: do not assume sk_buff_head list is empty in error handling s390/ctcm: Delete unnecessary checks before the macro call “dev_kfree_skb” net: ena: don't wake up tx queue when down drop_monitor: Better sanitize notified packets ...
Diffstat (limited to 'net/can/j1939/main.c')
-rw-r--r--net/can/j1939/main.c403
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);