Add more drivers in support of the CAN IoT card

linux_kernel_modules/can/0-can.mdef

+sources:
+{
+    proc.c
+    af_can.c
+}
+

linux_kernel_modules/can/1-can-bcm.mdef

+sources:
+{
+    bcm.c
+}

linux_kernel_modules/can/1-can-raw.mdef

+sources:
+{
+    raw.c
+}

linux_kernel_modules/can/2-vcan.mdef

+sources:
+{
+    vcan.c
+}

linux_kernel_modules/can/af_can.c

+/*
+ * af_can.c - Protocol family CAN core module
+ *            (used by different CAN protocol modules)
+ *
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/stddef.h>
+#include <linux/init.h>
+#include <linux/kmod.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/rcupdate.h>
+#include <linux/uaccess.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <linux/if_ether.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <linux/can.h>
+#include <linux/can/core.h>
+#include <linux/can/skb.h>
+#include <linux/ratelimit.h>
+#include <net/net_namespace.h>
+#include <net/sock.h>
+
+#include "af_can.h"
+
+static __initconst const char banner[] = KERN_INFO
+	"can: controller area network core (" CAN_VERSION_STRING ")\n";
+
+MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
+	      "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
+
+MODULE_ALIAS_NETPROTO(PF_CAN);
+
+static int stats_timer __read_mostly = 1;
+module_param(stats_timer, int, S_IRUGO);
+MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)");
+
+/* receive filters subscribed for 'all' CAN devices */
+struct dev_rcv_lists can_rx_alldev_list;
+static DEFINE_SPINLOCK(can_rcvlists_lock);
+
+static struct kmem_cache *rcv_cache __read_mostly;
+
+/* table of registered CAN protocols */
+static const struct can_proto *proto_tab[CAN_NPROTO] __read_mostly;
+static DEFINE_MUTEX(proto_tab_lock);
+
+struct timer_list can_stattimer;   /* timer for statistics update */
+struct s_stats    can_stats;       /* packet statistics */
+struct s_pstats   can_pstats;      /* receive list statistics */
+
+/*
+ * af_can socket functions
+ */
+
+int can_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	struct sock *sk = sock->sk;
+
+	switch (cmd) {
+
+	case SIOCGSTAMP:
+		return sock_get_timestamp(sk, (struct timeval __user *)arg);
+
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+EXPORT_SYMBOL(can_ioctl);
+
+static void can_sock_destruct(struct sock *sk)
+{
+	skb_queue_purge(&sk->sk_receive_queue);
+}
+
+static const struct can_proto *can_get_proto(int protocol)
+{
+	const struct can_proto *cp;
+
+	rcu_read_lock();
+	cp = rcu_dereference(proto_tab[protocol]);
+	if (cp && !try_module_get(cp->prot->owner))
+		cp = NULL;
+	rcu_read_unlock();
+
+	return cp;
+}
+
+static inline void can_put_proto(const struct can_proto *cp)
+{
+	module_put(cp->prot->owner);
+}
+
+static int can_create(struct net *net, struct socket *sock, int protocol,
+		      int kern)
+{
+	struct sock *sk;
+	const struct can_proto *cp;
+	int err = 0;
+
+	sock->state = SS_UNCONNECTED;
+
+	if (protocol < 0 || protocol >= CAN_NPROTO)
+		return -EINVAL;
+
+	if (!net_eq(net, &init_net))
+		return -EAFNOSUPPORT;
+
+	cp = can_get_proto(protocol);
+
+#ifdef CONFIG_MODULES
+	if (!cp) {
+		/* try to load protocol module if kernel is modular */
+
+		err = request_module("can-proto-%d", protocol);
+
+		/*
+		 * In case of error we only print a message but don't
+		 * return the error code immediately.  Below we will
+		 * return -EPROTONOSUPPORT
+		 */
+		if (err)
+			printk_ratelimited(KERN_ERR "can: request_module "
+			       "(can-proto-%d) failed.\n", protocol);
+
+		cp = can_get_proto(protocol);
+	}
+#endif
+
+	/* check for available protocol and correct usage */
+
+	if (!cp)
+		return -EPROTONOSUPPORT;
+
+	if (cp->type != sock->type) {
+		err = -EPROTOTYPE;
+		goto errout;
+	}
+
+	sock->ops = cp->ops;
+
+	sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot);
+	if (!sk) {
+		err = -ENOMEM;
+		goto errout;
+	}
+
+	sock_init_data(sock, sk);
+	sk->sk_destruct = can_sock_destruct;
+
+	if (sk->sk_prot->init)
+		err = sk->sk_prot->init(sk);
+
+	if (err) {
+		/* release sk on errors */
+		sock_orphan(sk);
+		sock_put(sk);
+	}
+
+ errout:
+	can_put_proto(cp);
+	return err;
+}
+
+/*
+ * af_can tx path
+ */
+
+/**
+ * can_send - transmit a CAN frame (optional with local loopback)
+ * @skb: pointer to socket buffer with CAN frame in data section
+ * @loop: loopback for listeners on local CAN sockets (recommended default!)
+ *
+ * Due to the loopback this routine must not be called from hardirq context.
+ *
+ * Return:
+ *  0 on success
+ *  -ENETDOWN when the selected interface is down
+ *  -ENOBUFS on full driver queue (see net_xmit_errno())
+ *  -ENOMEM when local loopback failed at calling skb_clone()
+ *  -EPERM when trying to send on a non-CAN interface
+ *  -EMSGSIZE CAN frame size is bigger than CAN interface MTU
+ *  -EINVAL when the skb->data does not contain a valid CAN frame
+ */
+int can_send(struct sk_buff *skb, int loop)
+{
+	struct sk_buff *newskb = NULL;
+	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+	int err = -EINVAL;
+
+	if (skb->len == CAN_MTU) {
+		skb->protocol = htons(ETH_P_CAN);
+		if (unlikely(cfd->len > CAN_MAX_DLEN))
+			goto inval_skb;
+	} else if (skb->len == CANFD_MTU) {
+		skb->protocol = htons(ETH_P_CANFD);
+		if (unlikely(cfd->len > CANFD_MAX_DLEN))
+			goto inval_skb;
+	} else
+		goto inval_skb;
+
+	/*
+	 * Make sure the CAN frame can pass the selected CAN netdevice.
+	 * As structs can_frame and canfd_frame are similar, we can provide
+	 * CAN FD frames to legacy CAN drivers as long as the length is <= 8
+	 */
+	if (unlikely(skb->len > skb->dev->mtu && cfd->len > CAN_MAX_DLEN)) {
+		err = -EMSGSIZE;
+		goto inval_skb;
+	}
+
+	if (unlikely(skb->dev->type != ARPHRD_CAN)) {
+		err = -EPERM;
+		goto inval_skb;
+	}
+
+	if (unlikely(!(skb->dev->flags & IFF_UP))) {
+		err = -ENETDOWN;
+		goto inval_skb;
+	}
+
+	skb_reset_network_header(skb);
+	skb_reset_transport_header(skb);
+
+	if (loop) {
+		/* local loopback of sent CAN frames */
+
+		/* indication for the CAN driver: do loopback */
+		skb->pkt_type = PACKET_LOOPBACK;
+
+		/*
+		 * The reference to the originating sock may be required
+		 * by the receiving socket to check whether the frame is
+		 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
+		 * Therefore we have to ensure that skb->sk remains the
+		 * reference to the originating sock by restoring skb->sk
+		 * after each skb_clone() or skb_orphan() usage.
+		 */
+
+		if (!(skb->dev->flags & IFF_ECHO)) {
+			/*
+			 * If the interface is not capable to do loopback
+			 * itself, we do it here.
+			 */
+			newskb = skb_clone(skb, GFP_ATOMIC);
+			if (!newskb) {
+				kfree_skb(skb);
+				return -ENOMEM;
+			}
+
+			can_skb_set_owner(newskb, skb->sk);
+			newskb->ip_summed = CHECKSUM_UNNECESSARY;
+			newskb->pkt_type = PACKET_BROADCAST;
+		}
+	} else {
+		/* indication for the CAN driver: no loopback required */
+		skb->pkt_type = PACKET_HOST;
+	}
+
+	/* send to netdevice */
+	err = dev_queue_xmit(skb);
+	if (err > 0)
+		err = net_xmit_errno(err);
+
+	if (err) {
+		kfree_skb(newskb);
+		return err;
+	}
+
+	if (newskb)
+		netif_rx_ni(newskb);
+
+	/* update statistics */
+	can_stats.tx_frames++;
+	can_stats.tx_frames_delta++;
+
+	return 0;
+
+inval_skb:
+	kfree_skb(skb);
+	return err;
+}
+EXPORT_SYMBOL(can_send);
+
+/*
+ * af_can rx path
+ */
+
+static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev)
+{
+	if (!dev)
+		return &can_rx_alldev_list;
+	else
+		return (struct dev_rcv_lists *)dev->ml_priv;
+}
+
+/**
+ * find_rcv_list - determine optimal filterlist inside device filter struct
+ * @can_id: pointer to CAN identifier of a given can_filter
+ * @mask: pointer to CAN mask of a given can_filter
+ * @d: pointer to the device filter struct
+ *
+ * Description:
+ *  Returns the optimal filterlist to reduce the filter handling in the
+ *  receive path. This function is called by service functions that need
+ *  to register or unregister a can_filter in the filter lists.
+ *
+ *  A filter matches in general, when
+ *
+ *          <received_can_id> & mask == can_id & mask
+ *
+ *  so every bit set in the mask (even CAN_EFF_FLAG, CAN_RTR_FLAG) describe
+ *  relevant bits for the filter.
+ *
+ *  The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
+ *  filter for error messages (CAN_ERR_FLAG bit set in mask). For error msg
+ *  frames there is a special filterlist and a special rx path filter handling.
+ *
+ * Return:
+ *  Pointer to optimal filterlist for the given can_id/mask pair.
+ *  Constistency checked mask.
+ *  Reduced can_id to have a preprocessed filter compare value.
+ */
+static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
+					struct dev_rcv_lists *d)
+{
+	canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking */
+
+	/* filter for error message frames in extra filterlist */
+	if (*mask & CAN_ERR_FLAG) {
+		/* clear CAN_ERR_FLAG in filter entry */
+		*mask &= CAN_ERR_MASK;
+		return &d->rx[RX_ERR];
+	}
+
+	/* with cleared CAN_ERR_FLAG we have a simple mask/value filterpair */
+
+#define CAN_EFF_RTR_FLAGS (CAN_EFF_FLAG | CAN_RTR_FLAG)
+
+	/* ensure valid values in can_mask for 'SFF only' frame filtering */
+	if ((*mask & CAN_EFF_FLAG) && !(*can_id & CAN_EFF_FLAG))
+		*mask &= (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS);
+
+	/* reduce condition testing at receive time */
+	*can_id &= *mask;
+
+	/* inverse can_id/can_mask filter */
+	if (inv)
+		return &d->rx[RX_INV];
+
+	/* mask == 0 => no condition testing at receive time */
+	if (!(*mask))
+		return &d->rx[RX_ALL];
+
+	/* extra filterlists for the subscription of a single non-RTR can_id */
+	if (((*mask & CAN_EFF_RTR_FLAGS) == CAN_EFF_RTR_FLAGS) &&
+	    !(*can_id & CAN_RTR_FLAG)) {
+
+		if (*can_id & CAN_EFF_FLAG) {
+			if (*mask == (CAN_EFF_MASK | CAN_EFF_RTR_FLAGS)) {
+				/* RFC: a future use-case for hash-tables? */
+				return &d->rx[RX_EFF];
+			}
+		} else {
+			if (*mask == (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS))
+				return &d->rx_sff[*can_id];
+		}
+	}
+
+	/* default: filter via can_id/can_mask */
+	return &d->rx[RX_FIL];
+}
+
+/**
+ * can_rx_register - subscribe CAN frames from a specific interface
+ * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
+ * @can_id: CAN identifier (see description)
+ * @mask: CAN mask (see description)
+ * @func: callback function on filter match
+ * @data: returned parameter for callback function
+ * @ident: string for calling module identification
+ *
+ * Description:
+ *  Invokes the callback function with the received sk_buff and the given
+ *  parameter 'data' on a matching receive filter. A filter matches, when
+ *
+ *          <received_can_id> & mask == can_id & mask
+ *
+ *  The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
+ *  filter for error message frames (CAN_ERR_FLAG bit set in mask).
+ *
+ *  The provided pointer to the sk_buff is guaranteed to be valid as long as
+ *  the callback function is running. The callback function must *not* free
+ *  the given sk_buff while processing it's task. When the given sk_buff is
+ *  needed after the end of the callback function it must be cloned inside
+ *  the callback function with skb_clone().
+ *
+ * Return:
+ *  0 on success
+ *  -ENOMEM on missing cache mem to create subscription entry
+ *  -ENODEV unknown device
+ */
+int can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
+		    void (*func)(struct sk_buff *, void *), void *data,
+		    char *ident)
+{
+	struct receiver *r;
+	struct hlist_head *rl;
+	struct dev_rcv_lists *d;
+	int err = 0;
+
+	/* insert new receiver  (dev,canid,mask) -> (func,data) */
+
+	if (dev && dev->type != ARPHRD_CAN)
+		return -ENODEV;
+
+	r = kmem_cache_alloc(rcv_cache, GFP_KERNEL);
+	if (!r)
+		return -ENOMEM;
+
+	spin_lock(&can_rcvlists_lock);
+
+	d = find_dev_rcv_lists(dev);
+	if (d) {
+		rl = find_rcv_list(&can_id, &mask, d);
+
+		r->can_id  = can_id;
+		r->mask    = mask;
+		r->matches = 0;
+		r->func    = func;
+		r->data    = data;
+		r->ident   = ident;
+
+		hlist_add_head_rcu(&r->list, rl);
+		d->entries++;
+
+		can_pstats.rcv_entries++;
+		if (can_pstats.rcv_entries_max < can_pstats.rcv_entries)
+			can_pstats.rcv_entries_max = can_pstats.rcv_entries;
+	} else {
+		kmem_cache_free(rcv_cache, r);
+		err = -ENODEV;
+	}
+
+	spin_unlock(&can_rcvlists_lock);
+
+	return err;
+}
+EXPORT_SYMBOL(can_rx_register);
+
+/*
+ * can_rx_delete_receiver - rcu callback for single receiver entry removal
+ */
+static void can_rx_delete_receiver(struct rcu_head *rp)
+{
+	struct receiver *r = container_of(rp, struct receiver, rcu);
+
+	kmem_cache_free(rcv_cache, r);
+}
+
+/**
+ * can_rx_unregister - unsubscribe CAN frames from a specific interface
+ * @dev: pointer to netdevice (NULL => unsubcribe from 'all' CAN devices list)
+ * @can_id: CAN identifier
+ * @mask: CAN mask
+ * @func: callback function on filter match
+ * @data: returned parameter for callback function
+ *
+ * Description:
+ *  Removes subscription entry depending on given (subscription) values.
+ */
+void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
+		       void (*func)(struct sk_buff *, void *), void *data)
+{
+	struct receiver *r = NULL;
+	struct hlist_head *rl;
+	struct dev_rcv_lists *d;
+
+	if (dev && dev->type != ARPHRD_CAN)
+		return;
+
+	spin_lock(&can_rcvlists_lock);
+
+	d = find_dev_rcv_lists(dev);
+	if (!d) {
+		pr_err("BUG: receive list not found for "
+		       "dev %s, id %03X, mask %03X\n",
+		       DNAME(dev), can_id, mask);
+		goto out;
+	}
+
+	rl = find_rcv_list(&can_id, &mask, d);
+
+	/*
+	 * Search the receiver list for the item to delete.  This should
+	 * exist, since no receiver may be unregistered that hasn't
+	 * been registered before.
+	 */
+
+	hlist_for_each_entry_rcu(r, rl, list) {
+		if (r->can_id == can_id && r->mask == mask &&
+		    r->func == func && r->data == data)
+			break;
+	}
+
+	/*
+	 * Check for bugs in CAN protocol implementations using af_can.c:
+	 * 'r' will be NULL if no matching list item was found for removal.
+	 */
+
+	if (!r) {
+		WARN(1, "BUG: receive list entry not found for dev %s, "
+		     "id %03X, mask %03X\n", DNAME(dev), can_id, mask);
+		goto out;
+	}
+
+	hlist_del_rcu(&r->list);
+	d->entries--;
+
+	if (can_pstats.rcv_entries > 0)
+		can_pstats.rcv_entries--;
+
+	/* remove device structure requested by NETDEV_UNREGISTER */
+	if (d->remove_on_zero_entries && !d->entries) {
+		kfree(d);
+		dev->ml_priv = NULL;
+	}
+
+ out:
+	spin_unlock(&can_rcvlists_lock);
+
+	/* schedule the receiver item for deletion */
+	if (r)
+		call_rcu(&r->rcu, can_rx_delete_receiver);
+}
+EXPORT_SYMBOL(can_rx_unregister);
+
+static inline void deliver(struct sk_buff *skb, struct receiver *r)
+{
+	r->func(skb, r->data);
+	r->matches++;
+}
+
+static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb)
+{
+	struct receiver *r;
+	int matches = 0;
+	struct can_frame *cf = (struct can_frame *)skb->data;
+	canid_t can_id = cf->can_id;
+
+	if (d->entries == 0)
+		return 0;
+
+	if (can_id & CAN_ERR_FLAG) {
+		/* check for error message frame entries only */
+		hlist_for_each_entry_rcu(r, &d->rx[RX_ERR], list) {
+			if (can_id & r->mask) {
+				deliver(skb, r);
+				matches++;
+			}
+		}
+		return matches;
+	}
+
+	/* check for unfiltered entries */
+	hlist_for_each_entry_rcu(r, &d->rx[RX_ALL], list) {
+		deliver(skb, r);
+		matches++;
+	}
+
+	/* check for can_id/mask entries */
+	hlist_for_each_entry_rcu(r, &d->rx[RX_FIL], list) {
+		if ((can_id & r->mask) == r->can_id) {
+			deliver(skb, r);
+			matches++;
+		}
+	}
+
+	/* check for inverted can_id/mask entries */
+	hlist_for_each_entry_rcu(r, &d->rx[RX_INV], list) {
+		if ((can_id & r->mask) != r->can_id) {
+			deliver(skb, r);
+			matches++;
+		}
+	}
+
+	/* check filterlists for single non-RTR can_ids */
+	if (can_id & CAN_RTR_FLAG)
+		return matches;
+
+	if (can_id & CAN_EFF_FLAG) {
+		hlist_for_each_entry_rcu(r, &d->rx[RX_EFF], list) {
+			if (r->can_id == can_id) {
+				deliver(skb, r);
+				matches++;
+			}
+		}
+	} else {
+		can_id &= CAN_SFF_MASK;
+		hlist_for_each_entry_rcu(r, &d->rx_sff[can_id], list) {
+			deliver(skb, r);
+			matches++;
+		}
+	}
+
+	return matches;
+}
+
+static void can_receive(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dev_rcv_lists *d;
+	int matches;
+
+	/* update statistics */
+	can_stats.rx_frames++;
+	can_stats.rx_frames_delta++;
+
+	rcu_read_lock();
+
+	/* deliver the packet to sockets listening on all devices */
+	matches = can_rcv_filter(&can_rx_alldev_list, skb);
+
+	/* find receive list for this device */
+	d = find_dev_rcv_lists(dev);
+	if (d)
+		matches += can_rcv_filter(d, skb);
+
+	rcu_read_unlock();
+
+	/* consume the skbuff allocated by the netdevice driver */
+	consume_skb(skb);
+
+	if (matches > 0) {
+		can_stats.matches++;
+		can_stats.matches_delta++;
+	}
+}
+
+static int can_rcv(struct sk_buff *skb, struct net_device *dev,
+		   struct packet_type *pt, struct net_device *orig_dev)
+{
+	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
+	if (unlikely(!net_eq(dev_net(dev), &init_net)))
+		goto drop;
+
+	if (WARN_ONCE(dev->type != ARPHRD_CAN ||
+		      skb->len != CAN_MTU ||
+		      cfd->len > CAN_MAX_DLEN,
+		      "PF_CAN: dropped non conform CAN skbuf: "
+		      "dev type %d, len %d, datalen %d\n",
+		      dev->type, skb->len, cfd->len))
+		goto drop;
+
+	can_receive(skb, dev);
+	return NET_RX_SUCCESS;
+
+drop:
+	kfree_skb(skb);
+	return NET_RX_DROP;
+}
+
+static int canfd_rcv(struct sk_buff *skb, struct net_device *dev,
+		   struct packet_type *pt, struct net_device *orig_dev)
+{
+	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
+	if (unlikely(!net_eq(dev_net(dev), &init_net)))
+		goto drop;
+
+	if (WARN_ONCE(dev->type != ARPHRD_CAN ||
+		      skb->len != CANFD_MTU ||
+		      cfd->len > CANFD_MAX_DLEN,
+		      "PF_CAN: dropped non conform CAN FD skbuf: "
+		      "dev type %d, len %d, datalen %d\n",
+		      dev->type, skb->len, cfd->len))
+		goto drop;
+
+	can_receive(skb, dev);
+	return NET_RX_SUCCESS;
+
+drop:
+	kfree_skb(skb);
+	return NET_RX_DROP;
+}
+
+/*
+ * af_can protocol functions
+ */
+
+/**
+ * can_proto_register - register CAN transport protocol
+ * @cp: pointer to CAN protocol structure
+ *
+ * Return:
+ *  0 on success
+ *  -EINVAL invalid (out of range) protocol number
+ *  -EBUSY  protocol already in use
+ *  -ENOBUF if proto_register() fails
+ */
+int can_proto_register(const struct can_proto *cp)
+{
+	int proto = cp->protocol;
+	int err = 0;
+
+	if (proto < 0 || proto >= CAN_NPROTO) {
+		pr_err("can: protocol number %d out of range\n", proto);
+		return -EINVAL;
+	}
+
+	err = proto_register(cp->prot, 0);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&proto_tab_lock);
+
+	if (proto_tab[proto]) {
+		pr_err("can: protocol %d already registered\n", proto);
+		err = -EBUSY;
+	} else
+		RCU_INIT_POINTER(proto_tab[proto], cp);
+
+	mutex_unlock(&proto_tab_lock);
+
+	if (err < 0)
+		proto_unregister(cp->prot);
+
+	return err;
+}
+EXPORT_SYMBOL(can_proto_register);
+
+/**
+ * can_proto_unregister - unregister CAN transport protocol
+ * @cp: pointer to CAN protocol structure
+ */
+void can_proto_unregister(const struct can_proto *cp)
+{
+	int proto = cp->protocol;
+
+	mutex_lock(&proto_tab_lock);
+	BUG_ON(proto_tab[proto] != cp);
+	RCU_INIT_POINTER(proto_tab[proto], NULL);
+	mutex_unlock(&proto_tab_lock);
+
+	synchronize_rcu();
+
+	proto_unregister(cp->prot);
+}
+EXPORT_SYMBOL(can_proto_unregister);
+
+/*
+ * af_can notifier to create/remove CAN netdevice specific structs
+ */
+static int can_notifier(struct notifier_block *nb, unsigned long msg,
+			void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct dev_rcv_lists *d;
+
+	if (!net_eq(dev_net(dev), &init_net))
+		return NOTIFY_DONE;
+
+	if (dev->type != ARPHRD_CAN)
+		return NOTIFY_DONE;
+
+	switch (msg) {
+
+	case NETDEV_REGISTER:
+
+		/* create new dev_rcv_lists for this device */
+		d = kzalloc(sizeof(*d), GFP_KERNEL);
+		if (!d)
+			return NOTIFY_DONE;
+		BUG_ON(dev->ml_priv);
+		dev->ml_priv = d;
+
+		break;
+
+	case NETDEV_UNREGISTER:
+		spin_lock(&can_rcvlists_lock);
+
+		d = dev->ml_priv;
+		if (d) {
+			if (d->entries)
+				d->remove_on_zero_entries = 1;
+			else {
+				kfree(d);
+				dev->ml_priv = NULL;
+			}
+		} else
+			pr_err("can: notifier: receive list not found for dev "
+			       "%s\n", dev->name);
+
+		spin_unlock(&can_rcvlists_lock);
+
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+/*
+ * af_can module init/exit functions
+ */
+
+static struct packet_type can_packet __read_mostly = {
+	.type = cpu_to_be16(ETH_P_CAN),
+	.func = can_rcv,
+};
+
+static struct packet_type canfd_packet __read_mostly = {
+	.type = cpu_to_be16(ETH_P_CANFD),
+	.func = canfd_rcv,
+};
+
+static const struct net_proto_family can_family_ops = {
+	.family = PF_CAN,
+	.create = can_create,
+	.owner  = THIS_MODULE,
+};
+
+/* notifier block for netdevice event */
+static struct notifier_block can_netdev_notifier __read_mostly = {
+	.notifier_call = can_notifier,
+};
+
+static __init int can_init(void)
+{
+	/* check for correct padding to be able to use the structs similarly */
+	BUILD_BUG_ON(offsetof(struct can_frame, can_dlc) !=
+		     offsetof(struct canfd_frame, len) ||
+		     offsetof(struct can_frame, data) !=
+		     offsetof(struct canfd_frame, data));
+
+	printk(banner);
+
+	memset(&can_rx_alldev_list, 0, sizeof(can_rx_alldev_list));
+
+	rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
+				      0, 0, NULL);
+	if (!rcv_cache)
+		return -ENOMEM;
+
+	if (stats_timer) {
+		/* the statistics are updated every second (timer triggered) */
+		setup_timer(&can_stattimer, can_stat_update, 0);
+		mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
+	} else
+		can_stattimer.function = NULL;
+
+	can_init_proc();
+
+	/* protocol register */
+	sock_register(&can_family_ops);
+	register_netdevice_notifier(&can_netdev_notifier);
+	dev_add_pack(&can_packet);
+	dev_add_pack(&canfd_packet);
+
+	return 0;
+}
+
+static __exit void can_exit(void)
+{
+	struct net_device *dev;
+
+	if (stats_timer)
+		del_timer_sync(&can_stattimer);
+
+	can_remove_proc();
+
+	/* protocol unregister */
+	dev_remove_pack(&canfd_packet);
+	dev_remove_pack(&can_packet);
+	unregister_netdevice_notifier(&can_netdev_notifier);
+	sock_unregister(PF_CAN);
+
+	/* remove created dev_rcv_lists from still registered CAN devices */
+	rcu_read_lock();
+	for_each_netdev_rcu(&init_net, dev) {
+		if (dev->type == ARPHRD_CAN && dev->ml_priv) {
+
+			struct dev_rcv_lists *d = dev->ml_priv;
+
+			BUG_ON(d->entries);
+			kfree(d);
+			dev->ml_priv = NULL;
+		}
+	}
+	rcu_read_unlock();
+
+	rcu_barrier(); /* Wait for completion of call_rcu()'s */
+
+	kmem_cache_destroy(rcv_cache);
+}
+
+module_init(can_init);
+module_exit(can_exit);

linux_kernel_modules/can/af_can.h

+/*
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#ifndef AF_CAN_H
+#define AF_CAN_H
+
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/list.h>
+#include <linux/rcupdate.h>
+#include <linux/can.h>
+
+/* af_can rx dispatcher structures */
+
+struct receiver {
+	struct hlist_node list;
+	struct rcu_head rcu;
+	canid_t can_id;
+	canid_t mask;
+	unsigned long matches;
+	void (*func)(struct sk_buff *, void *);
+	void *data;
+	char *ident;
+};
+
+enum { RX_ERR, RX_ALL, RX_FIL, RX_INV, RX_EFF, RX_MAX };
+
+/* per device receive filters linked at dev->ml_priv */
+struct dev_rcv_lists {
+	struct hlist_head rx[RX_MAX];
+	struct hlist_head rx_sff[0x800];
+	int remove_on_zero_entries;
+	int entries;
+};
+
+/* statistic structures */
+
+/* can be reset e.g. by can_init_stats() */
+struct s_stats {
+	unsigned long jiffies_init;
+
+	unsigned long rx_frames;
+	unsigned long tx_frames;
+	unsigned long matches;
+
+	unsigned long total_rx_rate;
+	unsigned long total_tx_rate;
+	unsigned long total_rx_match_ratio;
+
+	unsigned long current_rx_rate;
+	unsigned long current_tx_rate;
+	unsigned long current_rx_match_ratio;
+
+	unsigned long max_rx_rate;
+	unsigned long max_tx_rate;
+	unsigned long max_rx_match_ratio;
+
+	unsigned long rx_frames_delta;
+	unsigned long tx_frames_delta;
+	unsigned long matches_delta;
+};
+
+/* persistent statistics */
+struct s_pstats {
+	unsigned long stats_reset;
+	unsigned long user_reset;
+	unsigned long rcv_entries;
+	unsigned long rcv_entries_max;
+};
+
+/* receive filters subscribed for 'all' CAN devices */
+extern struct dev_rcv_lists can_rx_alldev_list;
+
+/* function prototypes for the CAN networklayer procfs (proc.c) */
+void can_init_proc(void);
+void can_remove_proc(void);
+void can_stat_update(unsigned long data);
+
+/* structures and variables from af_can.c needed in proc.c for reading */
+extern struct timer_list can_stattimer;    /* timer for statistics update */
+extern struct s_stats    can_stats;        /* packet statistics */
+extern struct s_pstats   can_pstats;       /* receive list statistics */
+extern struct hlist_head can_rx_dev_list;  /* rx dispatcher structures */
+
+#endif /* AF_CAN_H */

linux_kernel_modules/can/bcm.c

+/*
+ * bcm.c - Broadcast Manager to filter/send (cyclic) CAN content
+ *
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/hrtimer.h>
+#include <linux/list.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/uio.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <linux/can.h>
+#include <linux/can/core.h>
+#include <linux/can/skb.h>
+#include <linux/can/bcm.h>
+#include <linux/slab.h>
+#include <net/sock.h>
+#include <net/net_namespace.h>
+
+/*
+ * To send multiple CAN frame content within TX_SETUP or to filter
+ * CAN messages with multiplex index within RX_SETUP, the number of
+ * different filters is limited to 256 due to the one byte index value.
+ */
+#define MAX_NFRAMES 256
+
+/* use of last_frames[index].can_dlc */
+#define RX_RECV    0x40 /* received data for this element */
+#define RX_THR     0x80 /* element not been sent due to throttle feature */
+#define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
+
+/* get best masking value for can_rx_register() for a given single can_id */
+#define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
+		     (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
+		     (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
+
+#define CAN_BCM_VERSION CAN_VERSION
+static __initconst const char banner[] = KERN_INFO
+	"can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n";
+
+MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
+MODULE_ALIAS("can-proto-2");
+
+/* easy access to can_frame payload */
+static inline u64 GET_U64(const struct can_frame *cp)
+{
+	return *(u64 *)cp->data;
+}
+
+struct bcm_op {
+	struct list_head list;
+	int ifindex;
+	canid_t can_id;
+	u32 flags;
+	unsigned long frames_abs, frames_filtered;
+	struct timeval ival1, ival2;
+	struct hrtimer timer, thrtimer;
+	struct tasklet_struct tsklet, thrtsklet;
+	ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg;
+	int rx_ifindex;
+	u32 count;
+	u32 nframes;
+	u32 currframe;
+	struct can_frame *frames;
+	struct can_frame *last_frames;
+	struct can_frame sframe;
+	struct can_frame last_sframe;
+	struct sock *sk;
+	struct net_device *rx_reg_dev;
+};
+
+static struct proc_dir_entry *proc_dir;
+
+struct bcm_sock {
+	struct sock sk;
+	int bound;
+	int ifindex;
+	struct notifier_block notifier;
+	struct list_head rx_ops;
+	struct list_head tx_ops;
+	unsigned long dropped_usr_msgs;
+	struct proc_dir_entry *bcm_proc_read;
+	char procname [32]; /* inode number in decimal with \0 */
+};
+
+static inline struct bcm_sock *bcm_sk(const struct sock *sk)
+{
+	return (struct bcm_sock *)sk;
+}
+
+#define CFSIZ sizeof(struct can_frame)
+#define OPSIZ sizeof(struct bcm_op)
+#define MHSIZ sizeof(struct bcm_msg_head)
+
+/*
+ * procfs functions
+ */
+static char *bcm_proc_getifname(char *result, int ifindex)
+{
+	struct net_device *dev;
+
+	if (!ifindex)
+		return "any";
+
+	rcu_read_lock();
+	dev = dev_get_by_index_rcu(&init_net, ifindex);
+	if (dev)
+		strcpy(result, dev->name);
+	else
+		strcpy(result, "???");
+	rcu_read_unlock();
+
+	return result;
+}
+
+static int bcm_proc_show(struct seq_file *m, void *v)
+{
+	char ifname[IFNAMSIZ];
+	struct sock *sk = (struct sock *)m->private;
+	struct bcm_sock *bo = bcm_sk(sk);
+	struct bcm_op *op;
+
+	seq_printf(m, ">>> socket %pK", sk->sk_socket);
+	seq_printf(m, " / sk %pK", sk);
+	seq_printf(m, " / bo %pK", bo);
+	seq_printf(m, " / dropped %lu", bo->dropped_usr_msgs);
+	seq_printf(m, " / bound %s", bcm_proc_getifname(ifname, bo->ifindex));
+	seq_printf(m, " <<<\n");
+
+	list_for_each_entry(op, &bo->rx_ops, list) {
+
+		unsigned long reduction;
+
+		/* print only active entries & prevent division by zero */
+		if (!op->frames_abs)
+			continue;
+
+		seq_printf(m, "rx_op: %03X %-5s ",
+				op->can_id, bcm_proc_getifname(ifname, op->ifindex));
+		seq_printf(m, "[%u]%c ", op->nframes,
+				(op->flags & RX_CHECK_DLC)?'d':' ');
+		if (op->kt_ival1.tv64)
+			seq_printf(m, "timeo=%lld ",
+					(long long)
+					ktime_to_us(op->kt_ival1));
+
+		if (op->kt_ival2.tv64)
+			seq_printf(m, "thr=%lld ",
+					(long long)
+					ktime_to_us(op->kt_ival2));
+
+		seq_printf(m, "# recv %ld (%ld) => reduction: ",
+				op->frames_filtered, op->frames_abs);
+
+		reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
+
+		seq_printf(m, "%s%ld%%\n",
+				(reduction == 100)?"near ":"", reduction);
+	}
+
+	list_for_each_entry(op, &bo->tx_ops, list) {
+
+		seq_printf(m, "tx_op: %03X %s [%u] ",
+				op->can_id,
+				bcm_proc_getifname(ifname, op->ifindex),
+				op->nframes);
+
+		if (op->kt_ival1.tv64)
+			seq_printf(m, "t1=%lld ",
+					(long long) ktime_to_us(op->kt_ival1));
+
+		if (op->kt_ival2.tv64)
+			seq_printf(m, "t2=%lld ",
+					(long long) ktime_to_us(op->kt_ival2));
+
+		seq_printf(m, "# sent %ld\n", op->frames_abs);
+	}
+	seq_putc(m, '\n');
+	return 0;
+}
+
+static int bcm_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, bcm_proc_show, PDE_DATA(inode));
+}
+
+static const struct file_operations bcm_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= bcm_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+/*
+ * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
+ *              of the given bcm tx op
+ */
+static void bcm_can_tx(struct bcm_op *op)
+{
+	struct sk_buff *skb;
+	struct net_device *dev;
+	struct can_frame *cf = &op->frames[op->currframe];
+
+	/* no target device? => exit */
+	if (!op->ifindex)
+		return;
+
+	dev = dev_get_by_index(&init_net, op->ifindex);
+	if (!dev) {
+		/* RFC: should this bcm_op remove itself here? */
+		return;
+	}
+
+	skb = alloc_skb(CFSIZ + sizeof(struct can_skb_priv), gfp_any());
+	if (!skb)
+		goto out;
+
+	can_skb_reserve(skb);
+	can_skb_prv(skb)->ifindex = dev->ifindex;
+
+	memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
+
+	/* send with loopback */
+	skb->dev = dev;
+	can_skb_set_owner(skb, op->sk);
+	can_send(skb, 1);
+
+	/* update statistics */
+	op->currframe++;
+	op->frames_abs++;
+
+	/* reached last frame? */
+	if (op->currframe >= op->nframes)
+		op->currframe = 0;
+ out:
+	dev_put(dev);
+}
+
+/*
+ * bcm_send_to_user - send a BCM message to the userspace
+ *                    (consisting of bcm_msg_head + x CAN frames)
+ */
+static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
+			     struct can_frame *frames, int has_timestamp)
+{
+	struct sk_buff *skb;
+	struct can_frame *firstframe;
+	struct sockaddr_can *addr;
+	struct sock *sk = op->sk;
+	unsigned int datalen = head->nframes * CFSIZ;
+	int err;
+
+	skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
+	if (!skb)
+		return;
+
+	memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head));
+
+	if (head->nframes) {
+		/* can_frames starting here */
+		firstframe = (struct can_frame *)skb_tail_pointer(skb);
+
+		memcpy(skb_put(skb, datalen), frames, datalen);
+
+		/*
+		 * the BCM uses the can_dlc-element of the can_frame
+		 * structure for internal purposes. This is only
+		 * relevant for updates that are generated by the
+		 * BCM, where nframes is 1
+		 */
+		if (head->nframes == 1)
+			firstframe->can_dlc &= BCM_CAN_DLC_MASK;
+	}
+
+	if (has_timestamp) {
+		/* restore rx timestamp */
+		skb->tstamp = op->rx_stamp;
+	}
+
+	/*
+	 *  Put the datagram to the queue so that bcm_recvmsg() can
+	 *  get it from there.  We need to pass the interface index to
+	 *  bcm_recvmsg().  We pass a whole struct sockaddr_can in skb->cb
+	 *  containing the interface index.
+	 */
+
+	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
+	addr = (struct sockaddr_can *)skb->cb;
+	memset(addr, 0, sizeof(*addr));
+	addr->can_family  = AF_CAN;
+	addr->can_ifindex = op->rx_ifindex;
+
+	err = sock_queue_rcv_skb(sk, skb);
+	if (err < 0) {
+		struct bcm_sock *bo = bcm_sk(sk);
+
+		kfree_skb(skb);
+		/* don't care about overflows in this statistic */
+		bo->dropped_usr_msgs++;
+	}
+}
+
+static void bcm_tx_start_timer(struct bcm_op *op)
+{
+	if (op->kt_ival1.tv64 && op->count)
+		hrtimer_start(&op->timer,
+			      ktime_add(ktime_get(), op->kt_ival1),
+			      HRTIMER_MODE_ABS);
+	else if (op->kt_ival2.tv64)
+		hrtimer_start(&op->timer,
+			      ktime_add(ktime_get(), op->kt_ival2),
+			      HRTIMER_MODE_ABS);
+}
+
+static void bcm_tx_timeout_tsklet(unsigned long data)
+{
+	struct bcm_op *op = (struct bcm_op *)data;
+	struct bcm_msg_head msg_head;
+
+	if (op->kt_ival1.tv64 && (op->count > 0)) {
+
+		op->count--;
+		if (!op->count && (op->flags & TX_COUNTEVT)) {
+
+			/* create notification to user */
+			msg_head.opcode  = TX_EXPIRED;
+			msg_head.flags   = op->flags;
+			msg_head.count   = op->count;
+			msg_head.ival1   = op->ival1;
+			msg_head.ival2   = op->ival2;
+			msg_head.can_id  = op->can_id;
+			msg_head.nframes = 0;
+
+			bcm_send_to_user(op, &msg_head, NULL, 0);
+		}
+		bcm_can_tx(op);
+
+	} else if (op->kt_ival2.tv64)
+		bcm_can_tx(op);
+
+	bcm_tx_start_timer(op);
+}
+
+/*
+ * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions
+ */
+static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
+{
+	struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
+
+	tasklet_schedule(&op->tsklet);
+
+	return HRTIMER_NORESTART;
+}
+
+/*
+ * bcm_rx_changed - create a RX_CHANGED notification due to changed content
+ */
+static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
+{
+	struct bcm_msg_head head;
+
+	/* update statistics */
+	op->frames_filtered++;
+
+	/* prevent statistics overflow */
+	if (op->frames_filtered > ULONG_MAX/100)
+		op->frames_filtered = op->frames_abs = 0;
+
+	/* this element is not throttled anymore */
+	data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV);
+
+	head.opcode  = RX_CHANGED;
+	head.flags   = op->flags;
+	head.count   = op->count;
+	head.ival1   = op->ival1;
+	head.ival2   = op->ival2;
+	head.can_id  = op->can_id;
+	head.nframes = 1;
+
+	bcm_send_to_user(op, &head, data, 1);
+}
+
+/*
+ * bcm_rx_update_and_send - process a detected relevant receive content change
+ *                          1. update the last received data
+ *                          2. send a notification to the user (if possible)
+ */
+static void bcm_rx_update_and_send(struct bcm_op *op,
+				   struct can_frame *lastdata,
+				   const struct can_frame *rxdata)
+{
+	memcpy(lastdata, rxdata, CFSIZ);
+
+	/* mark as used and throttled by default */
+	lastdata->can_dlc |= (RX_RECV|RX_THR);
+
+	/* throtteling mode inactive ? */
+	if (!op->kt_ival2.tv64) {
+		/* send RX_CHANGED to the user immediately */
+		bcm_rx_changed(op, lastdata);
+		return;
+	}
+
+	/* with active throttling timer we are just done here */
+	if (hrtimer_active(&op->thrtimer))
+		return;
+
+	/* first receiption with enabled throttling mode */
+	if (!op->kt_lastmsg.tv64)
+		goto rx_changed_settime;
+
+	/* got a second frame inside a potential throttle period? */
+	if (ktime_us_delta(ktime_get(), op->kt_lastmsg) <
+	    ktime_to_us(op->kt_ival2)) {
+		/* do not send the saved data - only start throttle timer */
+		hrtimer_start(&op->thrtimer,
+			      ktime_add(op->kt_lastmsg, op->kt_ival2),
+			      HRTIMER_MODE_ABS);
+		return;
+	}
+
+	/* the gap was that big, that throttling was not needed here */
+rx_changed_settime:
+	bcm_rx_changed(op, lastdata);
+	op->kt_lastmsg = ktime_get();
+}
+
+/*
+ * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
+ *                       received data stored in op->last_frames[]
+ */
+static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index,
+				const struct can_frame *rxdata)
+{
+	/*
+	 * no one uses the MSBs of can_dlc for comparation,
+	 * so we use it here to detect the first time of reception
+	 */
+
+	if (!(op->last_frames[index].can_dlc & RX_RECV)) {
+		/* received data for the first time => send update to user */
+		bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
+		return;
+	}
+
+	/* do a real check in can_frame data section */
+
+	if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
+	    (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
+		bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
+		return;
+	}
+
+	if (op->flags & RX_CHECK_DLC) {
+		/* do a real check in can_frame dlc */
+		if (rxdata->can_dlc != (op->last_frames[index].can_dlc &
+					BCM_CAN_DLC_MASK)) {
+			bcm_rx_update_and_send(op, &op->last_frames[index],
+					       rxdata);
+			return;
+		}
+	}
+}
+
+/*
+ * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
+ */
+static void bcm_rx_starttimer(struct bcm_op *op)
+{
+	if (op->flags & RX_NO_AUTOTIMER)
+		return;
+
+	if (op->kt_ival1.tv64)
+		hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
+}
+
+static void bcm_rx_timeout_tsklet(unsigned long data)
+{
+	struct bcm_op *op = (struct bcm_op *)data;
+	struct bcm_msg_head msg_head;
+
+	/* create notification to user */
+	msg_head.opcode  = RX_TIMEOUT;
+	msg_head.flags   = op->flags;
+	msg_head.count   = op->count;
+	msg_head.ival1   = op->ival1;
+	msg_head.ival2   = op->ival2;
+	msg_head.can_id  = op->can_id;
+	msg_head.nframes = 0;
+
+	bcm_send_to_user(op, &msg_head, NULL, 0);
+}
+
+/*
+ * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
+ */
+static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
+{
+	struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
+
+	/* schedule before NET_RX_SOFTIRQ */
+	tasklet_hi_schedule(&op->tsklet);
+
+	/* no restart of the timer is done here! */
+
+	/* if user wants to be informed, when cyclic CAN-Messages come back */
+	if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) {
+		/* clear received can_frames to indicate 'nothing received' */
+		memset(op->last_frames, 0, op->nframes * CFSIZ);
+	}
+
+	return HRTIMER_NORESTART;
+}
+
+/*
+ * bcm_rx_do_flush - helper for bcm_rx_thr_flush
+ */
+static inline int bcm_rx_do_flush(struct bcm_op *op, int update,
+				  unsigned int index)
+{
+	if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) {
+		if (update)
+			bcm_rx_changed(op, &op->last_frames[index]);
+		return 1;
+	}
+	return 0;
+}
+
+/*
+ * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
+ *
+ * update == 0 : just check if throttled data is available  (any irq context)
+ * update == 1 : check and send throttled data to userspace (soft_irq context)
+ */
+static int bcm_rx_thr_flush(struct bcm_op *op, int update)
+{
+	int updated = 0;
+
+	if (op->nframes > 1) {
+		unsigned int i;
+
+		/* for MUX filter we start at index 1 */
+		for (i = 1; i < op->nframes; i++)
+			updated += bcm_rx_do_flush(op, update, i);
+
+	} else {
+		/* for RX_FILTER_ID and simple filter */
+		updated += bcm_rx_do_flush(op, update, 0);
+	}
+
+	return updated;
+}
+
+static void bcm_rx_thr_tsklet(unsigned long data)
+{
+	struct bcm_op *op = (struct bcm_op *)data;
+
+	/* push the changed data to the userspace */
+	bcm_rx_thr_flush(op, 1);
+}
+
+/*
+ * bcm_rx_thr_handler - the time for blocked content updates is over now:
+ *                      Check for throttled data and send it to the userspace
+ */
+static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer)
+{
+	struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer);
+
+	tasklet_schedule(&op->thrtsklet);
+
+	if (bcm_rx_thr_flush(op, 0)) {
+		hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
+		return HRTIMER_RESTART;
+	} else {
+		/* rearm throttle handling */
+		op->kt_lastmsg = ktime_set(0, 0);
+		return HRTIMER_NORESTART;
+	}
+}
+
+/*
+ * bcm_rx_handler - handle a CAN frame receiption
+ */
+static void bcm_rx_handler(struct sk_buff *skb, void *data)
+{
+	struct bcm_op *op = (struct bcm_op *)data;
+	const struct can_frame *rxframe = (struct can_frame *)skb->data;
+	unsigned int i;
+
+	/* disable timeout */
+	hrtimer_cancel(&op->timer);
+
+	if (op->can_id != rxframe->can_id)
+		return;
+
+	/* save rx timestamp */
+	op->rx_stamp = skb->tstamp;
+	/* save originator for recvfrom() */
+	op->rx_ifindex = skb->dev->ifindex;
+	/* update statistics */
+	op->frames_abs++;
+
+	if (op->flags & RX_RTR_FRAME) {
+		/* send reply for RTR-request (placed in op->frames[0]) */
+		bcm_can_tx(op);
+		return;
+	}
+
+	if (op->flags & RX_FILTER_ID) {
+		/* the easiest case */
+		bcm_rx_update_and_send(op, &op->last_frames[0], rxframe);
+		goto rx_starttimer;
+	}
+
+	if (op->nframes == 1) {
+		/* simple compare with index 0 */
+		bcm_rx_cmp_to_index(op, 0, rxframe);
+		goto rx_starttimer;
+	}
+
+	if (op->nframes > 1) {
+		/*
+		 * multiplex compare
+		 *
+		 * find the first multiplex mask that fits.
+		 * Remark: The MUX-mask is stored in index 0
+		 */
+
+		for (i = 1; i < op->nframes; i++) {
+			if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) ==
+			    (GET_U64(&op->frames[0]) &
+			     GET_U64(&op->frames[i]))) {
+				bcm_rx_cmp_to_index(op, i, rxframe);
+				break;
+			}
+		}
+	}
+
+rx_starttimer:
+	bcm_rx_starttimer(op);
+}
+
+/*
+ * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
+ */
+static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id,
+				  int ifindex)
+{
+	struct bcm_op *op;
+
+	list_for_each_entry(op, ops, list) {
+		if ((op->can_id == can_id) && (op->ifindex == ifindex))
+			return op;
+	}
+
+	return NULL;
+}
+
+static void bcm_remove_op(struct bcm_op *op)
+{
+	hrtimer_cancel(&op->timer);
+	hrtimer_cancel(&op->thrtimer);
+
+	if (op->tsklet.func)
+		tasklet_kill(&op->tsklet);
+
+	if (op->thrtsklet.func)
+		tasklet_kill(&op->thrtsklet);
+
+	if ((op->frames) && (op->frames != &op->sframe))
+		kfree(op->frames);
+
+	if ((op->last_frames) && (op->last_frames != &op->last_sframe))
+		kfree(op->last_frames);
+
+	kfree(op);
+}
+
+static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op)
+{
+	if (op->rx_reg_dev == dev) {
+		can_rx_unregister(dev, op->can_id, REGMASK(op->can_id),
+				  bcm_rx_handler, op);
+
+		/* mark as removed subscription */
+		op->rx_reg_dev = NULL;
+	} else
+		printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device "
+		       "mismatch %p %p\n", op->rx_reg_dev, dev);
+}
+
+/*
+ * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
+ */
+static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex)
+{
+	struct bcm_op *op, *n;
+
+	list_for_each_entry_safe(op, n, ops, list) {
+		if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
+
+			/*
+			 * Don't care if we're bound or not (due to netdev
+			 * problems) can_rx_unregister() is always a save
+			 * thing to do here.
+			 */
+			if (op->ifindex) {
+				/*
+				 * Only remove subscriptions that had not
+				 * been removed due to NETDEV_UNREGISTER
+				 * in bcm_notifier()
+				 */
+				if (op->rx_reg_dev) {
+					struct net_device *dev;
+
+					dev = dev_get_by_index(&init_net,
+							       op->ifindex);
+					if (dev) {
+						bcm_rx_unreg(dev, op);
+						dev_put(dev);
+					}
+				}
+			} else
+				can_rx_unregister(NULL, op->can_id,
+						  REGMASK(op->can_id),
+						  bcm_rx_handler, op);
+
+			list_del(&op->list);
+			bcm_remove_op(op);
+			return 1; /* done */
+		}
+	}
+
+	return 0; /* not found */
+}
+
+/*
+ * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
+ */
+static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex)
+{
+	struct bcm_op *op, *n;
+
+	list_for_each_entry_safe(op, n, ops, list) {
+		if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
+			list_del(&op->list);
+			bcm_remove_op(op);
+			return 1; /* done */
+		}
+	}
+
+	return 0; /* not found */
+}
+
+/*
+ * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
+ */
+static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head,
+		       int ifindex)
+{
+	struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex);
+
+	if (!op)
+		return -EINVAL;
+
+	/* put current values into msg_head */
+	msg_head->flags   = op->flags;
+	msg_head->count   = op->count;
+	msg_head->ival1   = op->ival1;
+	msg_head->ival2   = op->ival2;
+	msg_head->nframes = op->nframes;
+
+	bcm_send_to_user(op, msg_head, op->frames, 0);
+
+	return MHSIZ;
+}
+
+/*
+ * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
+ */
+static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
+			int ifindex, struct sock *sk)
+{
+	struct bcm_sock *bo = bcm_sk(sk);
+	struct bcm_op *op;
+	unsigned int i;
+	int err;
+
+	/* we need a real device to send frames */
+	if (!ifindex)
+		return -ENODEV;
+
+	/* check nframes boundaries - we need at least one can_frame */
+	if (msg_head->nframes < 1 || msg_head->nframes > MAX_NFRAMES)
+		return -EINVAL;
+
+	/* check the given can_id */
+	op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex);
+
+	if (op) {
+		/* update existing BCM operation */
+
+		/*
+		 * Do we need more space for the can_frames than currently
+		 * allocated? -> This is a _really_ unusual use-case and
+		 * therefore (complexity / locking) it is not supported.
+		 */
+		if (msg_head->nframes > op->nframes)
+			return -E2BIG;
+
+		/* update can_frames content */
+		for (i = 0; i < msg_head->nframes; i++) {
+			err = memcpy_fromiovec((u8 *)&op->frames[i],
+					       msg->msg_iov, CFSIZ);
+
+			if (op->frames[i].can_dlc > 8)
+				err = -EINVAL;
+
+			if (err < 0)
+				return err;
+
+			if (msg_head->flags & TX_CP_CAN_ID) {
+				/* copy can_id into frame */
+				op->frames[i].can_id = msg_head->can_id;
+			}
+		}
+
+	} else {
+		/* insert new BCM operation for the given can_id */
+
+		op = kzalloc(OPSIZ, GFP_KERNEL);
+		if (!op)
+			return -ENOMEM;
+
+		op->can_id    = msg_head->can_id;
+
+		/* create array for can_frames and copy the data */
+		if (msg_head->nframes > 1) {
+			op->frames = kmalloc(msg_head->nframes * CFSIZ,
+					     GFP_KERNEL);
+			if (!op->frames) {
+				kfree(op);
+				return -ENOMEM;
+			}
+		} else
+			op->frames = &op->sframe;
+
+		for (i = 0; i < msg_head->nframes; i++) {
+			err = memcpy_fromiovec((u8 *)&op->frames[i],
+					       msg->msg_iov, CFSIZ);
+
+			if (op->frames[i].can_dlc > 8)
+				err = -EINVAL;
+
+			if (err < 0) {
+				if (op->frames != &op->sframe)
+					kfree(op->frames);
+				kfree(op);
+				return err;
+			}
+
+			if (msg_head->flags & TX_CP_CAN_ID) {
+				/* copy can_id into frame */
+				op->frames[i].can_id = msg_head->can_id;
+			}
+		}
+
+		/* tx_ops never compare with previous received messages */
+		op->last_frames = NULL;
+
+		/* bcm_can_tx / bcm_tx_timeout_handler needs this */
+		op->sk = sk;
+		op->ifindex = ifindex;
+
+		/* initialize uninitialized (kzalloc) structure */
+		hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		op->timer.function = bcm_tx_timeout_handler;
+
+		/* initialize tasklet for tx countevent notification */
+		tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet,
+			     (unsigned long) op);
+
+		/* currently unused in tx_ops */
+		hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+
+		/* add this bcm_op to the list of the tx_ops */
+		list_add(&op->list, &bo->tx_ops);
+
+	} /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
+
+	if (op->nframes != msg_head->nframes) {
+		op->nframes   = msg_head->nframes;
+		/* start multiple frame transmission with index 0 */
+		op->currframe = 0;
+	}
+
+	/* check flags */
+
+	op->flags = msg_head->flags;
+
+	if (op->flags & TX_RESET_MULTI_IDX) {
+		/* start multiple frame transmission with index 0 */
+		op->currframe = 0;
+	}
+
+	if (op->flags & SETTIMER) {
+		/* set timer values */
+		op->count = msg_head->count;
+		op->ival1 = msg_head->ival1;
+		op->ival2 = msg_head->ival2;
+		op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
+		op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
+
+		/* disable an active timer due to zero values? */
+		if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64)
+			hrtimer_cancel(&op->timer);
+	}
+
+	if (op->flags & STARTTIMER) {
+		hrtimer_cancel(&op->timer);
+		/* spec: send can_frame when starting timer */
+		op->flags |= TX_ANNOUNCE;
+	}
+
+	if (op->flags & TX_ANNOUNCE) {
+		bcm_can_tx(op);
+		if (op->count)
+			op->count--;
+	}
+
+	if (op->flags & STARTTIMER)
+		bcm_tx_start_timer(op);
+
+	return msg_head->nframes * CFSIZ + MHSIZ;
+}
+
+/*
+ * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
+ */
+static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
+			int ifindex, struct sock *sk)
+{
+	struct bcm_sock *bo = bcm_sk(sk);
+	struct bcm_op *op;
+	int do_rx_register;
+	int err = 0;
+
+	if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) {
+		/* be robust against wrong usage ... */
+		msg_head->flags |= RX_FILTER_ID;
+		/* ignore trailing garbage */
+		msg_head->nframes = 0;
+	}
+
+	/* the first element contains the mux-mask => MAX_NFRAMES + 1  */
+	if (msg_head->nframes > MAX_NFRAMES + 1)
+		return -EINVAL;
+
+	if ((msg_head->flags & RX_RTR_FRAME) &&
+	    ((msg_head->nframes != 1) ||
+	     (!(msg_head->can_id & CAN_RTR_FLAG))))
+		return -EINVAL;
+
+	/* check the given can_id */
+	op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex);
+	if (op) {
+		/* update existing BCM operation */
+
+		/*
+		 * Do we need more space for the can_frames than currently
+		 * allocated? -> This is a _really_ unusual use-case and
+		 * therefore (complexity / locking) it is not supported.
+		 */
+		if (msg_head->nframes > op->nframes)
+			return -E2BIG;
+
+		if (msg_head->nframes) {
+			/* update can_frames content */
+			err = memcpy_fromiovec((u8 *)op->frames,
+					       msg->msg_iov,
+					       msg_head->nframes * CFSIZ);
+			if (err < 0)
+				return err;
+
+			/* clear last_frames to indicate 'nothing received' */
+			memset(op->last_frames, 0, msg_head->nframes * CFSIZ);
+		}
+
+		op->nframes = msg_head->nframes;
+
+		/* Only an update -> do not call can_rx_register() */
+		do_rx_register = 0;
+
+	} else {
+		/* insert new BCM operation for the given can_id */
+		op = kzalloc(OPSIZ, GFP_KERNEL);
+		if (!op)
+			return -ENOMEM;
+
+		op->can_id    = msg_head->can_id;
+		op->nframes   = msg_head->nframes;
+
+		if (msg_head->nframes > 1) {
+			/* create array for can_frames and copy the data */
+			op->frames = kmalloc(msg_head->nframes * CFSIZ,
+					     GFP_KERNEL);
+			if (!op->frames) {
+				kfree(op);
+				return -ENOMEM;
+			}
+
+			/* create and init array for received can_frames */
+			op->last_frames = kzalloc(msg_head->nframes * CFSIZ,
+						  GFP_KERNEL);
+			if (!op->last_frames) {
+				kfree(op->frames);
+				kfree(op);
+				return -ENOMEM;
+			}
+
+		} else {
+			op->frames = &op->sframe;
+			op->last_frames = &op->last_sframe;
+		}
+
+		if (msg_head->nframes) {
+			err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov,
+					       msg_head->nframes * CFSIZ);
+			if (err < 0) {
+				if (op->frames != &op->sframe)
+					kfree(op->frames);
+				if (op->last_frames != &op->last_sframe)
+					kfree(op->last_frames);
+				kfree(op);
+				return err;
+			}
+		}
+
+		/* bcm_can_tx / bcm_tx_timeout_handler needs this */
+		op->sk = sk;
+		op->ifindex = ifindex;
+
+		/* ifindex for timeout events w/o previous frame reception */
+		op->rx_ifindex = ifindex;
+
+		/* initialize uninitialized (kzalloc) structure */
+		hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		op->timer.function = bcm_rx_timeout_handler;
+
+		/* initialize tasklet for rx timeout notification */
+		tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet,
+			     (unsigned long) op);
+
+		hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		op->thrtimer.function = bcm_rx_thr_handler;
+
+		/* initialize tasklet for rx throttle handling */
+		tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet,
+			     (unsigned long) op);
+
+		/* add this bcm_op to the list of the rx_ops */
+		list_add(&op->list, &bo->rx_ops);
+
+		/* call can_rx_register() */
+		do_rx_register = 1;
+
+	} /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
+
+	/* check flags */
+	op->flags = msg_head->flags;
+
+	if (op->flags & RX_RTR_FRAME) {
+
+		/* no timers in RTR-mode */
+		hrtimer_cancel(&op->thrtimer);
+		hrtimer_cancel(&op->timer);
+
+		/*
+		 * funny feature in RX(!)_SETUP only for RTR-mode:
+		 * copy can_id into frame BUT without RTR-flag to
+		 * prevent a full-load-loopback-test ... ;-]
+		 */
+		if ((op->flags & TX_CP_CAN_ID) ||
+		    (op->frames[0].can_id == op->can_id))
+			op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG;
+
+	} else {
+		if (op->flags & SETTIMER) {
+
+			/* set timer value */
+			op->ival1 = msg_head->ival1;
+			op->ival2 = msg_head->ival2;
+			op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
+			op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
+
+			/* disable an active timer due to zero value? */
+			if (!op->kt_ival1.tv64)
+				hrtimer_cancel(&op->timer);
+
+			/*
+			 * In any case cancel the throttle timer, flush
+			 * potentially blocked msgs and reset throttle handling
+			 */
+			op->kt_lastmsg = ktime_set(0, 0);
+			hrtimer_cancel(&op->thrtimer);
+			bcm_rx_thr_flush(op, 1);
+		}
+
+		if ((op->flags & STARTTIMER) && op->kt_ival1.tv64)
+			hrtimer_start(&op->timer, op->kt_ival1,
+				      HRTIMER_MODE_REL);
+	}
+
+	/* now we can register for can_ids, if we added a new bcm_op */
+	if (do_rx_register) {
+		if (ifindex) {
+			struct net_device *dev;
+
+			dev = dev_get_by_index(&init_net, ifindex);
+			if (dev) {
+				err = can_rx_register(dev, op->can_id,
+						      REGMASK(op->can_id),
+						      bcm_rx_handler, op,
+						      "bcm");
+
+				op->rx_reg_dev = dev;
+				dev_put(dev);
+			}
+
+		} else
+			err = can_rx_register(NULL, op->can_id,
+					      REGMASK(op->can_id),
+					      bcm_rx_handler, op, "bcm");
+		if (err) {
+			/* this bcm rx op is broken -> remove it */
+			list_del(&op->list);
+			bcm_remove_op(op);
+			return err;
+		}
+	}
+
+	return msg_head->nframes * CFSIZ + MHSIZ;
+}
+
+/*
+ * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
+ */
+static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
+{
+	struct sk_buff *skb;
+	struct net_device *dev;
+	int err;
+
+	/* we need a real device to send frames */
+	if (!ifindex)
+		return -ENODEV;
+
+	skb = alloc_skb(CFSIZ + sizeof(struct can_skb_priv), GFP_KERNEL);
+	if (!skb)
+		return -ENOMEM;
+
+	can_skb_reserve(skb);
+
+	err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
+	if (err < 0) {
+		kfree_skb(skb);
+		return err;
+	}
+
+	dev = dev_get_by_index(&init_net, ifindex);
+	if (!dev) {
+		kfree_skb(skb);
+		return -ENODEV;
+	}
+
+	can_skb_prv(skb)->ifindex = dev->ifindex;
+	skb->dev = dev;
+	can_skb_set_owner(skb, sk);
+	err = can_send(skb, 1); /* send with loopback */
+	dev_put(dev);
+
+	if (err)
+		return err;
+
+	return CFSIZ + MHSIZ;
+}
+
+/*
+ * bcm_sendmsg - process BCM commands (opcodes) from the userspace
+ */
+static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock,
+		       struct msghdr *msg, size_t size)
+{
+	struct sock *sk = sock->sk;
+	struct bcm_sock *bo = bcm_sk(sk);
+	int ifindex = bo->ifindex; /* default ifindex for this bcm_op */
+	struct bcm_msg_head msg_head;
+	int ret; /* read bytes or error codes as return value */
+
+	if (!bo->bound)
+		return -ENOTCONN;
+
+	/* check for valid message length from userspace */
+	if (size < MHSIZ || (size - MHSIZ) % CFSIZ)
+		return -EINVAL;
+
+	/* check for alternative ifindex for this bcm_op */
+
+	if (!ifindex && msg->msg_name) {
+		/* no bound device as default => check msg_name */
+		DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
+
+		if (msg->msg_namelen < sizeof(*addr))
+			return -EINVAL;
+
+		if (addr->can_family != AF_CAN)
+			return -EINVAL;
+
+		/* ifindex from sendto() */
+		ifindex = addr->can_ifindex;
+
+		if (ifindex) {
+			struct net_device *dev;
+
+			dev = dev_get_by_index(&init_net, ifindex);
+			if (!dev)
+				return -ENODEV;
+
+			if (dev->type != ARPHRD_CAN) {
+				dev_put(dev);
+				return -ENODEV;
+			}
+
+			dev_put(dev);
+		}
+	}
+
+	/* read message head information */
+
+	ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ);
+	if (ret < 0)
+		return ret;
+
+	lock_sock(sk);
+
+	switch (msg_head.opcode) {
+
+	case TX_SETUP:
+		ret = bcm_tx_setup(&msg_head, msg, ifindex, sk);
+		break;
+
+	case RX_SETUP:
+		ret = bcm_rx_setup(&msg_head, msg, ifindex, sk);
+		break;
+
+	case TX_DELETE:
+		if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex))
+			ret = MHSIZ;
+		else
+			ret = -EINVAL;
+		break;
+
+	case RX_DELETE:
+		if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex))
+			ret = MHSIZ;
+		else
+			ret = -EINVAL;
+		break;
+
+	case TX_READ:
+		/* reuse msg_head for the reply to TX_READ */
+		msg_head.opcode  = TX_STATUS;
+		ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex);
+		break;
+
+	case RX_READ:
+		/* reuse msg_head for the reply to RX_READ */
+		msg_head.opcode  = RX_STATUS;
+		ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex);
+		break;
+
+	case TX_SEND:
+		/* we need exactly one can_frame behind the msg head */
+		if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ))
+			ret = -EINVAL;
+		else
+			ret = bcm_tx_send(msg, ifindex, sk);
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	release_sock(sk);
+
+	return ret;
+}
+
+/*
+ * notification handler for netdevice status changes
+ */
+static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
+			void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
+	struct sock *sk = &bo->sk;
+	struct bcm_op *op;
+	int notify_enodev = 0;
+
+	if (!net_eq(dev_net(dev), &init_net))
+		return NOTIFY_DONE;
+
+	if (dev->type != ARPHRD_CAN)
+		return NOTIFY_DONE;
+
+	switch (msg) {
+
+	case NETDEV_UNREGISTER:
+		lock_sock(sk);
+
+		/* remove device specific receive entries */
+		list_for_each_entry(op, &bo->rx_ops, list)
+			if (op->rx_reg_dev == dev)
+				bcm_rx_unreg(dev, op);
+
+		/* remove device reference, if this is our bound device */
+		if (bo->bound && bo->ifindex == dev->ifindex) {
+			bo->bound   = 0;
+			bo->ifindex = 0;
+			notify_enodev = 1;
+		}
+
+		release_sock(sk);
+
+		if (notify_enodev) {
+			sk->sk_err = ENODEV;
+			if (!sock_flag(sk, SOCK_DEAD))
+				sk->sk_error_report(sk);
+		}
+		break;
+
+	case NETDEV_DOWN:
+		if (bo->bound && bo->ifindex == dev->ifindex) {
+			sk->sk_err = ENETDOWN;
+			if (!sock_flag(sk, SOCK_DEAD))
+				sk->sk_error_report(sk);
+		}
+	}
+
+	return NOTIFY_DONE;
+}
+
+/*
+ * initial settings for all BCM sockets to be set at socket creation time
+ */
+static int bcm_init(struct sock *sk)
+{
+	struct bcm_sock *bo = bcm_sk(sk);
+
+	bo->bound            = 0;
+	bo->ifindex          = 0;
+	bo->dropped_usr_msgs = 0;
+	bo->bcm_proc_read    = NULL;
+
+	INIT_LIST_HEAD(&bo->tx_ops);
+	INIT_LIST_HEAD(&bo->rx_ops);
+
+	/* set notifier */
+	bo->notifier.notifier_call = bcm_notifier;
+
+	register_netdevice_notifier(&bo->notifier);
+
+	return 0;
+}
+
+/*
+ * standard socket functions
+ */
+static int bcm_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct bcm_sock *bo;
+	struct bcm_op *op, *next;
+
+	if (sk == NULL)
+		return 0;
+
+	bo = bcm_sk(sk);
+
+	/* remove bcm_ops, timer, rx_unregister(), etc. */
+
+	unregister_netdevice_notifier(&bo->notifier);
+
+	lock_sock(sk);
+
+	list_for_each_entry_safe(op, next, &bo->tx_ops, list)
+		bcm_remove_op(op);
+
+	list_for_each_entry_safe(op, next, &bo->rx_ops, list) {
+		/*
+		 * Don't care if we're bound or not (due to netdev problems)
+		 * can_rx_unregister() is always a save thing to do here.
+		 */
+		if (op->ifindex) {
+			/*
+			 * Only remove subscriptions that had not
+			 * been removed due to NETDEV_UNREGISTER
+			 * in bcm_notifier()
+			 */
+			if (op->rx_reg_dev) {
+				struct net_device *dev;
+
+				dev = dev_get_by_index(&init_net, op->ifindex);
+				if (dev) {
+					bcm_rx_unreg(dev, op);
+					dev_put(dev);
+				}
+			}
+		} else
+			can_rx_unregister(NULL, op->can_id,
+					  REGMASK(op->can_id),
+					  bcm_rx_handler, op);
+
+		bcm_remove_op(op);
+	}
+
+	/* remove procfs entry */
+	if (proc_dir && bo->bcm_proc_read)
+		remove_proc_entry(bo->procname, proc_dir);
+
+	/* remove device reference */
+	if (bo->bound) {
+		bo->bound   = 0;
+		bo->ifindex = 0;
+	}
+
+	sock_orphan(sk);
+	sock->sk = NULL;
+
+	release_sock(sk);
+	sock_put(sk);
+
+	return 0;
+}
+
+static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
+		       int flags)
+{
+	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
+	struct sock *sk = sock->sk;
+	struct bcm_sock *bo = bcm_sk(sk);
+
+	if (len < sizeof(*addr))
+		return -EINVAL;
+
+	if (bo->bound)
+		return -EISCONN;
+
+	/* bind a device to this socket */
+	if (addr->can_ifindex) {
+		struct net_device *dev;
+
+		dev = dev_get_by_index(&init_net, addr->can_ifindex);
+		if (!dev)
+			return -ENODEV;
+
+		if (dev->type != ARPHRD_CAN) {
+			dev_put(dev);
+			return -ENODEV;
+		}
+
+		bo->ifindex = dev->ifindex;
+		dev_put(dev);
+
+	} else {
+		/* no interface reference for ifindex = 0 ('any' CAN device) */
+		bo->ifindex = 0;
+	}
+
+	bo->bound = 1;
+
+	if (proc_dir) {
+		/* unique socket address as filename */
+		sprintf(bo->procname, "%lu", sock_i_ino(sk));
+		bo->bcm_proc_read = proc_create_data(bo->procname, 0644,
+						     proc_dir,
+						     &bcm_proc_fops, sk);
+	}
+
+	return 0;
+}
+
+static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock,
+		       struct msghdr *msg, size_t size, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct sk_buff *skb;
+	int error = 0;
+	int noblock;
+	int err;
+
+	noblock =  flags & MSG_DONTWAIT;
+	flags   &= ~MSG_DONTWAIT;
+	skb = skb_recv_datagram(sk, flags, noblock, &error);
+	if (!skb)
+		return error;
+
+	if (skb->len < size)
+		size = skb->len;
+
+	err = memcpy_toiovec(msg->msg_iov, skb->data, size);
+	if (err < 0) {
+		skb_free_datagram(sk, skb);
+		return err;
+	}
+
+	sock_recv_ts_and_drops(msg, sk, skb);
+
+	if (msg->msg_name) {
+		__sockaddr_check_size(sizeof(struct sockaddr_can));
+		msg->msg_namelen = sizeof(struct sockaddr_can);
+		memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
+	}
+
+	skb_free_datagram(sk, skb);
+
+	return size;
+}
+
+static const struct proto_ops bcm_ops = {
+	.family        = PF_CAN,
+	.release       = bcm_release,
+	.bind          = sock_no_bind,
+	.connect       = bcm_connect,
+	.socketpair    = sock_no_socketpair,
+	.accept        = sock_no_accept,
+	.getname       = sock_no_getname,
+	.poll          = datagram_poll,
+	.ioctl         = can_ioctl,	/* use can_ioctl() from af_can.c */
+	.listen        = sock_no_listen,
+	.shutdown      = sock_no_shutdown,
+	.setsockopt    = sock_no_setsockopt,
+	.getsockopt    = sock_no_getsockopt,
+	.sendmsg       = bcm_sendmsg,
+	.recvmsg       = bcm_recvmsg,
+	.mmap          = sock_no_mmap,
+	.sendpage      = sock_no_sendpage,
+};
+
+static struct proto bcm_proto __read_mostly = {
+	.name       = "CAN_BCM",
+	.owner      = THIS_MODULE,
+	.obj_size   = sizeof(struct bcm_sock),
+	.init       = bcm_init,
+};
+
+static const struct can_proto bcm_can_proto = {
+	.type       = SOCK_DGRAM,
+	.protocol   = CAN_BCM,
+	.ops        = &bcm_ops,
+	.prot       = &bcm_proto,
+};
+
+static int __init bcm_module_init(void)
+{
+	int err;
+
+	printk(banner);
+
+	err = can_proto_register(&bcm_can_proto);
+	if (err < 0) {
+		printk(KERN_ERR "can: registration of bcm protocol failed\n");
+		return err;
+	}
+
+	/* create /proc/net/can-bcm directory */
+	proc_dir = proc_mkdir("can-bcm", init_net.proc_net);
+	return 0;
+}
+
+static void __exit bcm_module_exit(void)
+{
+	can_proto_unregister(&bcm_can_proto);
+
+	if (proc_dir)
+		remove_proc_entry("can-bcm", init_net.proc_net);
+}
+
+module_init(bcm_module_init);
+module_exit(bcm_module_exit);

linux_kernel_modules/can/proc.c

+/*
+ * proc.c - procfs support for Protocol family CAN core module
+ *
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/list.h>
+#include <linux/rcupdate.h>
+#include <linux/if_arp.h>
+#include <linux/can/core.h>
+
+#include "af_can.h"
+
+/*
+ * proc filenames for the PF_CAN core
+ */
+
+#define CAN_PROC_VERSION     "version"
+#define CAN_PROC_STATS       "stats"
+#define CAN_PROC_RESET_STATS "reset_stats"
+#define CAN_PROC_RCVLIST_ALL "rcvlist_all"
+#define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
+#define CAN_PROC_RCVLIST_INV "rcvlist_inv"
+#define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
+#define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
+#define CAN_PROC_RCVLIST_ERR "rcvlist_err"
+
+static struct proc_dir_entry *can_dir;
+static struct proc_dir_entry *pde_version;
+static struct proc_dir_entry *pde_stats;
+static struct proc_dir_entry *pde_reset_stats;
+static struct proc_dir_entry *pde_rcvlist_all;
+static struct proc_dir_entry *pde_rcvlist_fil;
+static struct proc_dir_entry *pde_rcvlist_inv;
+static struct proc_dir_entry *pde_rcvlist_sff;
+static struct proc_dir_entry *pde_rcvlist_eff;
+static struct proc_dir_entry *pde_rcvlist_err;
+
+static int user_reset;
+
+static const char rx_list_name[][8] = {
+	[RX_ERR] = "rx_err",
+	[RX_ALL] = "rx_all",
+	[RX_FIL] = "rx_fil",
+	[RX_INV] = "rx_inv",
+	[RX_EFF] = "rx_eff",
+};
+
+/*
+ * af_can statistics stuff
+ */
+
+static void can_init_stats(void)
+{
+	/*
+	 * This memset function is called from a timer context (when
+	 * can_stattimer is active which is the default) OR in a process
+	 * context (reading the proc_fs when can_stattimer is disabled).
+	 */
+	memset(&can_stats, 0, sizeof(can_stats));
+	can_stats.jiffies_init = jiffies;
+
+	can_pstats.stats_reset++;
+
+	if (user_reset) {
+		user_reset = 0;
+		can_pstats.user_reset++;
+	}
+}
+
+static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
+			       unsigned long count)
+{
+	unsigned long rate;
+
+	if (oldjif == newjif)
+		return 0;
+
+	/* see can_stat_update() - this should NEVER happen! */
+	if (count > (ULONG_MAX / HZ)) {
+		printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
+		       count);
+		return 99999999;
+	}
+
+	rate = (count * HZ) / (newjif - oldjif);
+
+	return rate;
+}
+
+void can_stat_update(unsigned long data)
+{
+	unsigned long j = jiffies; /* snapshot */
+
+	/* restart counting in timer context on user request */
+	if (user_reset)
+		can_init_stats();
+
+	/* restart counting on jiffies overflow */
+	if (j < can_stats.jiffies_init)
+		can_init_stats();
+
+	/* prevent overflow in calc_rate() */
+	if (can_stats.rx_frames > (ULONG_MAX / HZ))
+		can_init_stats();
+
+	/* prevent overflow in calc_rate() */
+	if (can_stats.tx_frames > (ULONG_MAX / HZ))
+		can_init_stats();
+
+	/* matches overflow - very improbable */
+	if (can_stats.matches > (ULONG_MAX / 100))
+		can_init_stats();
+
+	/* calc total values */
+	if (can_stats.rx_frames)
+		can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
+			can_stats.rx_frames;
+
+	can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
+					    can_stats.tx_frames);
+	can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
+					    can_stats.rx_frames);
+
+	/* calc current values */
+	if (can_stats.rx_frames_delta)
+		can_stats.current_rx_match_ratio =
+			(can_stats.matches_delta * 100) /
+			can_stats.rx_frames_delta;
+
+	can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
+	can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);
+
+	/* check / update maximum values */
+	if (can_stats.max_tx_rate < can_stats.current_tx_rate)
+		can_stats.max_tx_rate = can_stats.current_tx_rate;
+
+	if (can_stats.max_rx_rate < can_stats.current_rx_rate)
+		can_stats.max_rx_rate = can_stats.current_rx_rate;
+
+	if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
+		can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;
+
+	/* clear values for 'current rate' calculation */
+	can_stats.tx_frames_delta = 0;
+	can_stats.rx_frames_delta = 0;
+	can_stats.matches_delta   = 0;
+
+	/* restart timer (one second) */
+	mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
+}
+
+/*
+ * proc read functions
+ */
+
+static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
+			      struct net_device *dev)
+{
+	struct receiver *r;
+
+	hlist_for_each_entry_rcu(r, rx_list, list) {
+		char *fmt = (r->can_id & CAN_EFF_FLAG)?
+			"   %-5s  %08x  %08x  %pK  %pK  %8ld  %s\n" :
+			"   %-5s     %03x    %08x  %pK  %pK  %8ld  %s\n";
+
+		seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
+				r->func, r->data, r->matches, r->ident);
+	}
+}
+
+static void can_print_recv_banner(struct seq_file *m)
+{
+	/*
+	 *                  can1.  00000000  00000000  00000000
+	 *                 .......          0  tp20
+	 */
+	seq_puts(m, "  device   can_id   can_mask  function"
+			"  userdata   matches  ident\n");
+}
+
+static int can_stats_proc_show(struct seq_file *m, void *v)
+{
+	seq_putc(m, '\n');
+	seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames);
+	seq_printf(m, " %8ld received frames (RXF)\n", can_stats.rx_frames);
+	seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches);
+
+	seq_putc(m, '\n');
+
+	if (can_stattimer.function == can_stat_update) {
+		seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
+				can_stats.total_rx_match_ratio);
+
+		seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
+				can_stats.total_tx_rate);
+		seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
+				can_stats.total_rx_rate);
+
+		seq_putc(m, '\n');
+
+		seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
+				can_stats.current_rx_match_ratio);
+
+		seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
+				can_stats.current_tx_rate);
+		seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
+				can_stats.current_rx_rate);
+
+		seq_putc(m, '\n');
+
+		seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
+				can_stats.max_rx_match_ratio);
+
+		seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
+				can_stats.max_tx_rate);
+		seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
+				can_stats.max_rx_rate);
+
+		seq_putc(m, '\n');
+	}
+
+	seq_printf(m, " %8ld current receive list entries (CRCV)\n",
+			can_pstats.rcv_entries);
+	seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
+			can_pstats.rcv_entries_max);
+
+	if (can_pstats.stats_reset)
+		seq_printf(m, "\n %8ld statistic resets (STR)\n",
+				can_pstats.stats_reset);
+
+	if (can_pstats.user_reset)
+		seq_printf(m, " %8ld user statistic resets (USTR)\n",
+				can_pstats.user_reset);
+
+	seq_putc(m, '\n');
+	return 0;
+}
+
+static int can_stats_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, can_stats_proc_show, NULL);
+}
+
+static const struct file_operations can_stats_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= can_stats_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int can_reset_stats_proc_show(struct seq_file *m, void *v)
+{
+	user_reset = 1;
+
+	if (can_stattimer.function == can_stat_update) {
+		seq_printf(m, "Scheduled statistic reset #%ld.\n",
+				can_pstats.stats_reset + 1);
+
+	} else {
+		if (can_stats.jiffies_init != jiffies)
+			can_init_stats();
+
+		seq_printf(m, "Performed statistic reset #%ld.\n",
+				can_pstats.stats_reset);
+	}
+	return 0;
+}
+
+static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, can_reset_stats_proc_show, NULL);
+}
+
+static const struct file_operations can_reset_stats_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= can_reset_stats_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int can_version_proc_show(struct seq_file *m, void *v)
+{
+	seq_printf(m, "%s\n", CAN_VERSION_STRING);
+	return 0;
+}
+
+static int can_version_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, can_version_proc_show, NULL);
+}
+
+static const struct file_operations can_version_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= can_version_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
+					     struct net_device *dev,
+					     struct dev_rcv_lists *d)
+{
+	if (!hlist_empty(&d->rx[idx])) {
+		can_print_recv_banner(m);
+		can_print_rcvlist(m, &d->rx[idx], dev);
+	} else
+		seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
+
+}
+
+static int can_rcvlist_proc_show(struct seq_file *m, void *v)
+{
+	/* double cast to prevent GCC warning */
+	int idx = (int)(long)m->private;
+	struct net_device *dev;
+	struct dev_rcv_lists *d;
+
+	seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
+
+	rcu_read_lock();
+
+	/* receive list for 'all' CAN devices (dev == NULL) */
+	d = &can_rx_alldev_list;
+	can_rcvlist_proc_show_one(m, idx, NULL, d);
+
+	/* receive list for registered CAN devices */
+	for_each_netdev_rcu(&init_net, dev) {
+		if (dev->type == ARPHRD_CAN && dev->ml_priv)
+			can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
+	}
+
+	rcu_read_unlock();
+
+	seq_putc(m, '\n');
+	return 0;
+}
+
+static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, can_rcvlist_proc_show, PDE_DATA(inode));
+}
+
+static const struct file_operations can_rcvlist_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= can_rcvlist_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static inline void can_rcvlist_sff_proc_show_one(struct seq_file *m,
+						 struct net_device *dev,
+						 struct dev_rcv_lists *d)
+{
+	int i;
+	int all_empty = 1;
+
+	/* check whether at least one list is non-empty */
+	for (i = 0; i < 0x800; i++)
+		if (!hlist_empty(&d->rx_sff[i])) {
+			all_empty = 0;
+			break;
+		}
+
+	if (!all_empty) {
+		can_print_recv_banner(m);
+		for (i = 0; i < 0x800; i++) {
+			if (!hlist_empty(&d->rx_sff[i]))
+				can_print_rcvlist(m, &d->rx_sff[i], dev);
+		}
+	} else
+		seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
+}
+
+static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
+{
+	struct net_device *dev;
+	struct dev_rcv_lists *d;
+
+	/* RX_SFF */
+	seq_puts(m, "\nreceive list 'rx_sff':\n");
+
+	rcu_read_lock();
+
+	/* sff receive list for 'all' CAN devices (dev == NULL) */
+	d = &can_rx_alldev_list;
+	can_rcvlist_sff_proc_show_one(m, NULL, d);
+
+	/* sff receive list for registered CAN devices */
+	for_each_netdev_rcu(&init_net, dev) {
+		if (dev->type == ARPHRD_CAN && dev->ml_priv)
+			can_rcvlist_sff_proc_show_one(m, dev, dev->ml_priv);
+	}
+
+	rcu_read_unlock();
+
+	seq_putc(m, '\n');
+	return 0;
+}
+
+static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, can_rcvlist_sff_proc_show, NULL);
+}
+
+static const struct file_operations can_rcvlist_sff_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= can_rcvlist_sff_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+/*
+ * proc utility functions
+ */
+
+static void can_remove_proc_readentry(const char *name)
+{
+	if (can_dir)
+		remove_proc_entry(name, can_dir);
+}
+
+/*
+ * can_init_proc - create main CAN proc directory and procfs entries
+ */
+void can_init_proc(void)
+{
+	/* create /proc/net/can directory */
+	can_dir = proc_mkdir("can", init_net.proc_net);
+
+	if (!can_dir) {
+		printk(KERN_INFO "can: failed to create /proc/net/can . "
+		       "CONFIG_PROC_FS missing?\n");
+		return;
+	}
+
+	/* own procfs entries from the AF_CAN core */
+	pde_version     = proc_create(CAN_PROC_VERSION, 0644, can_dir,
+				      &can_version_proc_fops);
+	pde_stats       = proc_create(CAN_PROC_STATS, 0644, can_dir,
+				      &can_stats_proc_fops);
+	pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
+				      &can_reset_stats_proc_fops);
+	pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
+					   &can_rcvlist_proc_fops, (void *)RX_ERR);
+	pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
+					   &can_rcvlist_proc_fops, (void *)RX_ALL);
+	pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
+					   &can_rcvlist_proc_fops, (void *)RX_FIL);
+	pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
+					   &can_rcvlist_proc_fops, (void *)RX_INV);
+	pde_rcvlist_eff = proc_create_data(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
+					   &can_rcvlist_proc_fops, (void *)RX_EFF);
+	pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
+				      &can_rcvlist_sff_proc_fops);
+}
+
+/*
+ * can_remove_proc - remove procfs entries and main CAN proc directory
+ */
+void can_remove_proc(void)
+{
+	if (pde_version)
+		can_remove_proc_readentry(CAN_PROC_VERSION);
+
+	if (pde_stats)
+		can_remove_proc_readentry(CAN_PROC_STATS);
+
+	if (pde_reset_stats)
+		can_remove_proc_readentry(CAN_PROC_RESET_STATS);
+
+	if (pde_rcvlist_err)
+		can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
+
+	if (pde_rcvlist_all)
+		can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
+
+	if (pde_rcvlist_fil)
+		can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
+
+	if (pde_rcvlist_inv)
+		can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
+
+	if (pde_rcvlist_eff)
+		can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
+
+	if (pde_rcvlist_sff)
+		can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
+
+	if (can_dir)
+		remove_proc_entry("can", init_net.proc_net);
+}

linux_kernel_modules/can/raw.c

+/*
+ * raw.c - Raw sockets for protocol family CAN
+ *
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/uio.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <linux/can.h>
+#include <linux/can/core.h>
+#include <linux/can/skb.h>
+#include <linux/can/raw.h>
+#include <net/sock.h>
+#include <net/net_namespace.h>
+
+#define CAN_RAW_VERSION CAN_VERSION
+static __initconst const char banner[] =
+	KERN_INFO "can: raw protocol (rev " CAN_RAW_VERSION ")\n";
+
+MODULE_DESCRIPTION("PF_CAN raw protocol");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
+MODULE_ALIAS("can-proto-1");
+
+#define MASK_ALL 0
+
+/*
+ * A raw socket has a list of can_filters attached to it, each receiving
+ * the CAN frames matching that filter.  If the filter list is empty,
+ * no CAN frames will be received by the socket.  The default after
+ * opening the socket, is to have one filter which receives all frames.
+ * The filter list is allocated dynamically with the exception of the
+ * list containing only one item.  This common case is optimized by
+ * storing the single filter in dfilter, to avoid using dynamic memory.
+ */
+
+struct raw_sock {
+	struct sock sk;
+	int bound;
+	int ifindex;
+	struct notifier_block notifier;
+	int loopback;
+	int recv_own_msgs;
+	int fd_frames;
+	int count;                 /* number of active filters */
+	struct can_filter dfilter; /* default/single filter */
+	struct can_filter *filter; /* pointer to filter(s) */
+	can_err_mask_t err_mask;
+};
+
+/*
+ * Return pointer to store the extra msg flags for raw_recvmsg().
+ * We use the space of one unsigned int beyond the 'struct sockaddr_can'
+ * in skb->cb.
+ */
+static inline unsigned int *raw_flags(struct sk_buff *skb)
+{
+	BUILD_BUG_ON(sizeof(skb->cb) <= (sizeof(struct sockaddr_can) +
+					 sizeof(unsigned int)));
+
+	/* return pointer after struct sockaddr_can */
+	return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
+}
+
+static inline struct raw_sock *raw_sk(const struct sock *sk)
+{
+	return (struct raw_sock *)sk;
+}
+
+static void raw_rcv(struct sk_buff *oskb, void *data)
+{
+	struct sock *sk = (struct sock *)data;
+	struct raw_sock *ro = raw_sk(sk);
+	struct sockaddr_can *addr;
+	struct sk_buff *skb;
+	unsigned int *pflags;
+
+	/* check the received tx sock reference */
+	if (!ro->recv_own_msgs && oskb->sk == sk)
+		return;
+
+	/* do not pass non-CAN2.0 frames to a legacy socket */
+	if (!ro->fd_frames && oskb->len != CAN_MTU)
+		return;
+
+	/* clone the given skb to be able to enqueue it into the rcv queue */
+	skb = skb_clone(oskb, GFP_ATOMIC);
+	if (!skb)
+		return;
+
+	/*
+	 *  Put the datagram to the queue so that raw_recvmsg() can
+	 *  get it from there.  We need to pass the interface index to
+	 *  raw_recvmsg().  We pass a whole struct sockaddr_can in skb->cb
+	 *  containing the interface index.
+	 */
+
+	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
+	addr = (struct sockaddr_can *)skb->cb;
+	memset(addr, 0, sizeof(*addr));
+	addr->can_family  = AF_CAN;
+	addr->can_ifindex = skb->dev->ifindex;
+
+	/* add CAN specific message flags for raw_recvmsg() */
+	pflags = raw_flags(skb);
+	*pflags = 0;
+	if (oskb->sk)
+		*pflags |= MSG_DONTROUTE;
+	if (oskb->sk == sk)
+		*pflags |= MSG_CONFIRM;
+
+	if (sock_queue_rcv_skb(sk, skb) < 0)
+		kfree_skb(skb);
+}
+
+static int raw_enable_filters(struct net_device *dev, struct sock *sk,
+			      struct can_filter *filter, int count)
+{
+	int err = 0;
+	int i;
+
+	for (i = 0; i < count; i++) {
+		err = can_rx_register(dev, filter[i].can_id,
+				      filter[i].can_mask,
+				      raw_rcv, sk, "raw");
+		if (err) {
+			/* clean up successfully registered filters */
+			while (--i >= 0)
+				can_rx_unregister(dev, filter[i].can_id,
+						  filter[i].can_mask,
+						  raw_rcv, sk);
+			break;
+		}
+	}
+
+	return err;
+}
+
+static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
+				can_err_mask_t err_mask)
+{
+	int err = 0;
+
+	if (err_mask)
+		err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
+				      raw_rcv, sk, "raw");
+
+	return err;
+}
+
+static void raw_disable_filters(struct net_device *dev, struct sock *sk,
+			      struct can_filter *filter, int count)
+{
+	int i;
+
+	for (i = 0; i < count; i++)
+		can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
+				  raw_rcv, sk);
+}
+
+static inline void raw_disable_errfilter(struct net_device *dev,
+					 struct sock *sk,
+					 can_err_mask_t err_mask)
+
+{
+	if (err_mask)
+		can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
+				  raw_rcv, sk);
+}
+
+static inline void raw_disable_allfilters(struct net_device *dev,
+					  struct sock *sk)
+{
+	struct raw_sock *ro = raw_sk(sk);
+
+	raw_disable_filters(dev, sk, ro->filter, ro->count);
+	raw_disable_errfilter(dev, sk, ro->err_mask);
+}
+
+static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
+{
+	struct raw_sock *ro = raw_sk(sk);
+	int err;
+
+	err = raw_enable_filters(dev, sk, ro->filter, ro->count);
+	if (!err) {
+		err = raw_enable_errfilter(dev, sk, ro->err_mask);
+		if (err)
+			raw_disable_filters(dev, sk, ro->filter, ro->count);
+	}
+
+	return err;
+}
+
+static int raw_notifier(struct notifier_block *nb,
+			unsigned long msg, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
+	struct sock *sk = &ro->sk;
+
+	if (!net_eq(dev_net(dev), &init_net))
+		return NOTIFY_DONE;
+
+	if (dev->type != ARPHRD_CAN)
+		return NOTIFY_DONE;
+
+	if (ro->ifindex != dev->ifindex)
+		return NOTIFY_DONE;
+
+	switch (msg) {
+
+	case NETDEV_UNREGISTER:
+		lock_sock(sk);
+		/* remove current filters & unregister */
+		if (ro->bound)
+			raw_disable_allfilters(dev, sk);
+
+		if (ro->count > 1)
+			kfree(ro->filter);
+
+		ro->ifindex = 0;
+		ro->bound   = 0;
+		ro->count   = 0;
+		release_sock(sk);
+
+		sk->sk_err = ENODEV;
+		if (!sock_flag(sk, SOCK_DEAD))
+			sk->sk_error_report(sk);
+		break;
+
+	case NETDEV_DOWN:
+		sk->sk_err = ENETDOWN;
+		if (!sock_flag(sk, SOCK_DEAD))
+			sk->sk_error_report(sk);
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int raw_init(struct sock *sk)
+{
+	struct raw_sock *ro = raw_sk(sk);
+
+	ro->bound            = 0;
+	ro->ifindex          = 0;
+
+	/* set default filter to single entry dfilter */
+	ro->dfilter.can_id   = 0;
+	ro->dfilter.can_mask = MASK_ALL;
+	ro->filter           = &ro->dfilter;
+	ro->count            = 1;
+
+	/* set default loopback behaviour */
+	ro->loopback         = 1;
+	ro->recv_own_msgs    = 0;
+	ro->fd_frames        = 0;
+
+	/* set notifier */
+	ro->notifier.notifier_call = raw_notifier;
+
+	register_netdevice_notifier(&ro->notifier);
+
+	return 0;
+}
+
+static int raw_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct raw_sock *ro;
+
+	if (!sk)
+		return 0;
+
+	ro = raw_sk(sk);
+
+	unregister_netdevice_notifier(&ro->notifier);
+
+	lock_sock(sk);
+
+	/* remove current filters & unregister */
+	if (ro->bound) {
+		if (ro->ifindex) {
+			struct net_device *dev;
+
+			dev = dev_get_by_index(&init_net, ro->ifindex);
+			if (dev) {
+				raw_disable_allfilters(dev, sk);
+				dev_put(dev);
+			}
+		} else
+			raw_disable_allfilters(NULL, sk);
+	}
+
+	if (ro->count > 1)
+		kfree(ro->filter);
+
+	ro->ifindex = 0;
+	ro->bound   = 0;
+	ro->count   = 0;
+
+	sock_orphan(sk);
+	sock->sk = NULL;
+
+	release_sock(sk);
+	sock_put(sk);
+
+	return 0;
+}
+
+static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
+{
+	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
+	struct sock *sk = sock->sk;
+	struct raw_sock *ro = raw_sk(sk);
+	int ifindex;
+	int err = 0;
+	int notify_enetdown = 0;
+
+	if (len < sizeof(*addr))
+		return -EINVAL;
+
+	lock_sock(sk);
+
+	if (ro->bound && addr->can_ifindex == ro->ifindex)
+		goto out;
+
+	if (addr->can_ifindex) {
+		struct net_device *dev;
+
+		dev = dev_get_by_index(&init_net, addr->can_ifindex);
+		if (!dev) {
+			err = -ENODEV;
+			goto out;
+		}
+		if (dev->type != ARPHRD_CAN) {
+			dev_put(dev);
+			err = -ENODEV;
+			goto out;
+		}
+		if (!(dev->flags & IFF_UP))
+			notify_enetdown = 1;
+
+		ifindex = dev->ifindex;
+
+		/* filters set by default/setsockopt */
+		err = raw_enable_allfilters(dev, sk);
+		dev_put(dev);
+	} else {
+		ifindex = 0;
+
+		/* filters set by default/setsockopt */
+		err = raw_enable_allfilters(NULL, sk);
+	}
+
+	if (!err) {
+		if (ro->bound) {
+			/* unregister old filters */
+			if (ro->ifindex) {
+				struct net_device *dev;
+
+				dev = dev_get_by_index(&init_net, ro->ifindex);
+				if (dev) {
+					raw_disable_allfilters(dev, sk);
+					dev_put(dev);
+				}
+			} else
+				raw_disable_allfilters(NULL, sk);
+		}
+		ro->ifindex = ifindex;
+		ro->bound = 1;
+	}
+
+ out:
+	release_sock(sk);
+
+	if (notify_enetdown) {
+		sk->sk_err = ENETDOWN;
+		if (!sock_flag(sk, SOCK_DEAD))
+			sk->sk_error_report(sk);
+	}
+
+	return err;
+}
+
+static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
+		       int *len, int peer)
+{
+	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
+	struct sock *sk = sock->sk;
+	struct raw_sock *ro = raw_sk(sk);
+
+	if (peer)
+		return -EOPNOTSUPP;
+
+	memset(addr, 0, sizeof(*addr));
+	addr->can_family  = AF_CAN;
+	addr->can_ifindex = ro->ifindex;
+
+	*len = sizeof(*addr);
+
+	return 0;
+}
+
+static int raw_setsockopt(struct socket *sock, int level, int optname,
+			  char __user *optval, unsigned int optlen)
+{
+	struct sock *sk = sock->sk;
+	struct raw_sock *ro = raw_sk(sk);
+	struct can_filter *filter = NULL;  /* dyn. alloc'ed filters */
+	struct can_filter sfilter;         /* single filter */
+	struct net_device *dev = NULL;
+	can_err_mask_t err_mask = 0;
+	int count = 0;
+	int err = 0;
+
+	if (level != SOL_CAN_RAW)
+		return -EINVAL;
+
+	switch (optname) {
+
+	case CAN_RAW_FILTER:
+		if (optlen % sizeof(struct can_filter) != 0)
+			return -EINVAL;
+
+		count = optlen / sizeof(struct can_filter);
+
+		if (count > 1) {
+			/* filter does not fit into dfilter => alloc space */
+			filter = memdup_user(optval, optlen);
+			if (IS_ERR(filter))
+				return PTR_ERR(filter);
+		} else if (count == 1) {
+			if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
+				return -EFAULT;
+		}
+
+		lock_sock(sk);
+
+		if (ro->bound && ro->ifindex)
+			dev = dev_get_by_index(&init_net, ro->ifindex);
+
+		if (ro->bound) {
+			/* (try to) register the new filters */
+			if (count == 1)
+				err = raw_enable_filters(dev, sk, &sfilter, 1);
+			else
+				err = raw_enable_filters(dev, sk, filter,
+							 count);
+			if (err) {
+				if (count > 1)
+					kfree(filter);
+				goto out_fil;
+			}
+
+			/* remove old filter registrations */
+			raw_disable_filters(dev, sk, ro->filter, ro->count);
+		}
+
+		/* remove old filter space */
+		if (ro->count > 1)
+			kfree(ro->filter);
+
+		/* link new filters to the socket */
+		if (count == 1) {
+			/* copy filter data for single filter */
+			ro->dfilter = sfilter;
+			filter = &ro->dfilter;
+		}
+		ro->filter = filter;
+		ro->count  = count;
+
+ out_fil:
+		if (dev)
+			dev_put(dev);
+
+		release_sock(sk);
+
+		break;
+
+	case CAN_RAW_ERR_FILTER:
+		if (optlen != sizeof(err_mask))
+			return -EINVAL;
+
+		if (copy_from_user(&err_mask, optval, optlen))
+			return -EFAULT;
+
+		err_mask &= CAN_ERR_MASK;
+
+		lock_sock(sk);
+
+		if (ro->bound && ro->ifindex)
+			dev = dev_get_by_index(&init_net, ro->ifindex);
+
+		/* remove current error mask */
+		if (ro->bound) {
+			/* (try to) register the new err_mask */
+			err = raw_enable_errfilter(dev, sk, err_mask);
+
+			if (err)
+				goto out_err;
+
+			/* remove old err_mask registration */
+			raw_disable_errfilter(dev, sk, ro->err_mask);
+		}
+
+		/* link new err_mask to the socket */
+		ro->err_mask = err_mask;
+
+ out_err:
+		if (dev)
+			dev_put(dev);
+
+		release_sock(sk);
+
+		break;
+
+	case CAN_RAW_LOOPBACK:
+		if (optlen != sizeof(ro->loopback))
+			return -EINVAL;
+
+		if (copy_from_user(&ro->loopback, optval, optlen))
+			return -EFAULT;
+
+		break;
+
+	case CAN_RAW_RECV_OWN_MSGS:
+		if (optlen != sizeof(ro->recv_own_msgs))
+			return -EINVAL;
+
+		if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
+			return -EFAULT;
+
+		break;
+
+	case CAN_RAW_FD_FRAMES:
+		if (optlen != sizeof(ro->fd_frames))
+			return -EINVAL;
+
+		if (copy_from_user(&ro->fd_frames, optval, optlen))
+			return -EFAULT;
+
+		break;
+
+	default:
+		return -ENOPROTOOPT;
+	}
+	return err;
+}
+
+static int raw_getsockopt(struct socket *sock, int level, int optname,
+			  char __user *optval, int __user *optlen)
+{
+	struct sock *sk = sock->sk;
+	struct raw_sock *ro = raw_sk(sk);
+	int len;
+	void *val;
+	int err = 0;
+
+	if (level != SOL_CAN_RAW)
+		return -EINVAL;
+	if (get_user(len, optlen))
+		return -EFAULT;
+	if (len < 0)
+		return -EINVAL;
+
+	switch (optname) {
+
+	case CAN_RAW_FILTER:
+		lock_sock(sk);
+		if (ro->count > 0) {
+			int fsize = ro->count * sizeof(struct can_filter);
+			if (len > fsize)
+				len = fsize;
+			if (copy_to_user(optval, ro->filter, len))
+				err = -EFAULT;
+		} else
+			len = 0;
+		release_sock(sk);
+
+		if (!err)
+			err = put_user(len, optlen);
+		return err;
+
+	case CAN_RAW_ERR_FILTER:
+		if (len > sizeof(can_err_mask_t))
+			len = sizeof(can_err_mask_t);
+		val = &ro->err_mask;
+		break;
+
+	case CAN_RAW_LOOPBACK:
+		if (len > sizeof(int))
+			len = sizeof(int);
+		val = &ro->loopback;
+		break;
+
+	case CAN_RAW_RECV_OWN_MSGS:
+		if (len > sizeof(int))
+			len = sizeof(int);
+		val = &ro->recv_own_msgs;
+		break;
+
+	case CAN_RAW_FD_FRAMES:
+		if (len > sizeof(int))
+			len = sizeof(int);
+		val = &ro->fd_frames;
+		break;
+
+	default:
+		return -ENOPROTOOPT;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, val, len))
+		return -EFAULT;
+	return 0;
+}
+
+static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
+		       struct msghdr *msg, size_t size)
+{
+	struct sock *sk = sock->sk;
+	struct raw_sock *ro = raw_sk(sk);
+	struct sk_buff *skb;
+	struct net_device *dev;
+	int ifindex;
+	int err;
+
+	if (msg->msg_name) {
+		DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
+
+		if (msg->msg_namelen < sizeof(*addr))
+			return -EINVAL;
+
+		if (addr->can_family != AF_CAN)
+			return -EINVAL;
+
+		ifindex = addr->can_ifindex;
+	} else
+		ifindex = ro->ifindex;
+
+	if (ro->fd_frames) {
+		if (unlikely(size != CANFD_MTU && size != CAN_MTU))
+			return -EINVAL;
+	} else {
+		if (unlikely(size != CAN_MTU))
+			return -EINVAL;
+	}
+
+	dev = dev_get_by_index(&init_net, ifindex);
+	if (!dev)
+		return -ENXIO;
+
+	skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
+				  msg->msg_flags & MSG_DONTWAIT, &err);
+	if (!skb)
+		goto put_dev;
+
+	can_skb_reserve(skb);
+	can_skb_prv(skb)->ifindex = dev->ifindex;
+
+	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
+	if (err < 0)
+		goto free_skb;
+
+	sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
+
+	skb->dev = dev;
+	skb->sk  = sk;
+	skb->priority = sk->sk_priority;
+
+	err = can_send(skb, ro->loopback);
+
+	dev_put(dev);
+
+	if (err)
+		goto send_failed;
+
+	return size;
+
+free_skb:
+	kfree_skb(skb);
+put_dev:
+	dev_put(dev);
+send_failed:
+	return err;
+}
+
+static int raw_recvmsg(struct kiocb *iocb, struct socket *sock,
+		       struct msghdr *msg, size_t size, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct sk_buff *skb;
+	int err = 0;
+	int noblock;
+
+	noblock =  flags & MSG_DONTWAIT;
+	flags   &= ~MSG_DONTWAIT;
+
+	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	if (!skb)
+		return err;
+
+	if (size < skb->len)
+		msg->msg_flags |= MSG_TRUNC;
+	else
+		size = skb->len;
+
+	err = memcpy_toiovec(msg->msg_iov, skb->data, size);
+	if (err < 0) {
+		skb_free_datagram(sk, skb);
+		return err;
+	}
+
+	sock_recv_ts_and_drops(msg, sk, skb);
+
+	if (msg->msg_name) {
+		__sockaddr_check_size(sizeof(struct sockaddr_can));
+		msg->msg_namelen = sizeof(struct sockaddr_can);
+		memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
+	}
+
+	/* assign the flags that have been recorded in raw_rcv() */
+	msg->msg_flags |= *(raw_flags(skb));
+
+	skb_free_datagram(sk, skb);
+
+	return size;
+}
+
+static const struct proto_ops raw_ops = {
+	.family        = PF_CAN,
+	.release       = raw_release,
+	.bind          = raw_bind,
+	.connect       = sock_no_connect,
+	.socketpair    = sock_no_socketpair,
+	.accept        = sock_no_accept,
+	.getname       = raw_getname,
+	.poll          = datagram_poll,
+	.ioctl         = can_ioctl,	/* use can_ioctl() from af_can.c */
+	.listen        = sock_no_listen,
+	.shutdown      = sock_no_shutdown,
+	.setsockopt    = raw_setsockopt,
+	.getsockopt    = raw_getsockopt,
+	.sendmsg       = raw_sendmsg,
+	.recvmsg       = raw_recvmsg,
+	.mmap          = sock_no_mmap,
+	.sendpage      = sock_no_sendpage,
+};
+
+static struct proto raw_proto __read_mostly = {
+	.name       = "CAN_RAW",
+	.owner      = THIS_MODULE,
+	.obj_size   = sizeof(struct raw_sock),
+	.init       = raw_init,
+};
+
+static const struct can_proto raw_can_proto = {
+	.type       = SOCK_RAW,
+	.protocol   = CAN_RAW,
+	.ops        = &raw_ops,
+	.prot       = &raw_proto,
+};
+
+static __init int raw_module_init(void)
+{
+	int err;
+
+	printk(banner);
+
+	err = can_proto_register(&raw_can_proto);
+	if (err < 0)
+		printk(KERN_ERR "can: registration of raw protocol failed\n");
+
+	return err;
+}
+
+static __exit void raw_module_exit(void)
+{
+	can_proto_unregister(&raw_can_proto);
+}
+
+module_init(raw_module_init);
+module_exit(raw_module_exit);

linux_kernel_modules/can/vcan.c

+/*
+ * vcan.c - Virtual CAN interface
+ *
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/skb.h>
+#include <linux/slab.h>
+#include <net/rtnetlink.h>
+
+static __initconst const char banner[] =
+	KERN_INFO "vcan: Virtual CAN interface driver\n";
+
+MODULE_DESCRIPTION("virtual CAN interface");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
+
+
+/*
+ * CAN test feature:
+ * Enable the echo on driver level for testing the CAN core echo modes.
+ * See Documentation/networking/can.txt for details.
+ */
+
+static bool echo; /* echo testing. Default: 0 (Off) */
+module_param(echo, bool, S_IRUGO);
+MODULE_PARM_DESC(echo, "Echo sent frames (for testing). Default: 0 (Off)");
+
+
+static void vcan_rx(struct sk_buff *skb, struct net_device *dev)
+{
+	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+	struct net_device_stats *stats = &dev->stats;
+
+	stats->rx_packets++;
+	stats->rx_bytes += cfd->len;
+
+	skb->pkt_type  = PACKET_BROADCAST;
+	skb->dev       = dev;
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+	netif_rx_ni(skb);
+}
+
+static netdev_tx_t vcan_tx(struct sk_buff *skb, struct net_device *dev)
+{
+	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+	struct net_device_stats *stats = &dev->stats;
+	int loop;
+
+	if (can_dropped_invalid_skb(dev, skb))
+		return NETDEV_TX_OK;
+
+	stats->tx_packets++;
+	stats->tx_bytes += cfd->len;
+
+	/* set flag whether this packet has to be looped back */
+	loop = skb->pkt_type == PACKET_LOOPBACK;
+
+	if (!echo) {
+		/* no echo handling available inside this driver */
+
+		if (loop) {
+			/*
+			 * only count the packets here, because the
+			 * CAN core already did the echo for us
+			 */
+			stats->rx_packets++;
+			stats->rx_bytes += cfd->len;
+		}
+		consume_skb(skb);
+		return NETDEV_TX_OK;
+	}
+
+	/* perform standard echo handling for CAN network interfaces */
+
+	if (loop) {
+
+		skb = can_create_echo_skb(skb);
+		if (!skb)
+			return NETDEV_TX_OK;
+
+		/* receive with packet counting */
+		vcan_rx(skb, dev);
+	} else {
+		/* no looped packets => no counting */
+		consume_skb(skb);
+	}
+	return NETDEV_TX_OK;
+}
+
+static int vcan_change_mtu(struct net_device *dev, int new_mtu)
+{
+	/* Do not allow changing the MTU while running */
+	if (dev->flags & IFF_UP)
+		return -EBUSY;
+
+	if (new_mtu != CAN_MTU && new_mtu != CANFD_MTU)
+		return -EINVAL;
+
+	dev->mtu = new_mtu;
+	return 0;
+}
+
+static const struct net_device_ops vcan_netdev_ops = {
+	.ndo_start_xmit = vcan_tx,
+	.ndo_change_mtu = vcan_change_mtu,
+};
+
+static void vcan_setup(struct net_device *dev)
+{
+	dev->type		= ARPHRD_CAN;
+	dev->mtu		= CAN_MTU;
+	dev->hard_header_len	= 0;
+	dev->addr_len		= 0;
+	dev->tx_queue_len	= 0;
+	dev->flags		= IFF_NOARP;
+
+	/* set flags according to driver capabilities */
+	if (echo)
+		dev->flags |= IFF_ECHO;
+
+	dev->netdev_ops		= &vcan_netdev_ops;
+	dev->destructor		= free_netdev;
+}
+
+static struct rtnl_link_ops vcan_link_ops __read_mostly = {
+	.kind	= "vcan",
+	.setup	= vcan_setup,
+};
+
+static __init int vcan_init_module(void)
+{
+	printk(banner);
+
+	if (echo)
+		printk(KERN_INFO "vcan: enabled echo on driver level.\n");
+
+	return rtnl_link_register(&vcan_link_ops);
+}
+
+static __exit void vcan_cleanup_module(void)
+{
+	rtnl_link_unregister(&vcan_link_ops);
+}
+
+module_init(vcan_init_module);
+module_exit(vcan_cleanup_module);

mangOH_Red.sdef

@@ -89,7 +89,13 @@ kernelModules:
     // Required for BQ24296
     $MANGOH_ROOT/linux_kernel_modules/bq24296/0-bq24296.mdef
 
-    // Support for the CAN IoT card
-    $MANGOH_ROOT/linux_kernel_modules/can-dev/0-can-dev.mdef
-    $MANGOH_ROOT/linux_kernel_modules/mcp251x/1-mcp251x.mdef
+    // Support for the CAN IoT card - CAN subsystem
+    // $MANGOH_ROOT/linux_kernel_modules/can/0-can.mdef
+    // $MANGOH_ROOT/linux_kernel_modules/can/1-can-raw.mdef
+    // $MANGOH_ROOT/linux_kernel_modules/can/1-can-bcm.mdef
+
+    // Support for the CAN IoT card - CAN drivers
+    // $MANGOH_ROOT/linux_kernel_modules/can/2-can-dev.mdef
+    // $MANGOH_ROOT/linux_kernel_modules/can/2-vcan.mdef
+    // $MANGOH_ROOT/linux_kernel_modules/can/3-mcp251x.mdef
 }