diff options
Diffstat (limited to 'net/can')
| -rw-r--r-- | net/can/Kconfig | 17 | ||||
| -rw-r--r-- | net/can/Makefile | 6 | ||||
| -rw-r--r-- | net/can/af_can.c | 861 | ||||
| -rw-r--r-- | net/can/af_can.h | 122 | ||||
| -rw-r--r-- | net/can/proc.c | 533 |
5 files changed, 1539 insertions, 0 deletions
diff --git a/net/can/Kconfig b/net/can/Kconfig new file mode 100644 index 0000000..8b92790 --- /dev/null +++ b/net/can/Kconfig @@ -0,0 +1,17 @@ +# +# Controller Area Network (CAN) network layer core configuration +# + +menuconfig CAN + depends on NET + tristate "CAN bus subsystem support" + ---help--- + Controller Area Network (CAN) is a slow (up to 1Mbit/s) serial + communications protocol which was developed by Bosch in + 1991, mainly for automotive, but now widely used in marine + (NMEA2000), industrial, and medical applications. + More information on the CAN network protocol family PF_CAN + is contained in <Documentation/networking/can.txt>. + + If you want CAN support you should say Y here and also to the + specific driver for your controller(s) below. diff --git a/net/can/Makefile b/net/can/Makefile new file mode 100644 index 0000000..4c7563c --- /dev/null +++ b/net/can/Makefile @@ -0,0 +1,6 @@ +# +# Makefile for the Linux Controller Area Network core. +# + +obj-$(CONFIG_CAN) += can.o +can-objs := af_can.o proc.o diff --git a/net/can/af_can.c b/net/can/af_can.c new file mode 100644 index 0000000..5158e88 --- /dev/null +++ b/net/can/af_can.c @@ -0,0 +1,861 @@ +/* + * 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. + * + * Send feedback to <socketcan-users@lists.berlios.de> + * + */ + +#include <linux/module.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 <net/net_namespace.h> +#include <net/sock.h> + +#include "af_can.h" + +static __initdata 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)"); + +HLIST_HEAD(can_rx_dev_list); +static 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 struct can_proto *proto_tab[CAN_NPROTO] __read_mostly; +static DEFINE_SPINLOCK(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 + */ + +static 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; + } +} + +static void can_sock_destruct(struct sock *sk) +{ + skb_queue_purge(&sk->sk_receive_queue); +} + +static int can_create(struct net *net, struct socket *sock, int protocol) +{ + struct sock *sk; + struct can_proto *cp; + char module_name[sizeof("can-proto-000")]; + int err = 0; + + sock->state = SS_UNCONNECTED; + + if (protocol < 0 || protocol >= CAN_NPROTO) + return -EINVAL; + + if (net != &init_net) + return -EAFNOSUPPORT; + + /* try to load protocol module, when CONFIG_KMOD is defined */ + if (!proto_tab[protocol]) { + sprintf(module_name, "can-proto-%d", protocol); + err = request_module(module_name); + + /* + * In case of error we only print a message but don't + * return the error code immediately. Below we will + * return -EPROTONOSUPPORT + */ + if (err == -ENOSYS) { + if (printk_ratelimit()) + printk(KERN_INFO "can: request_module(%s)" + " not implemented.\n", module_name); + } else if (err) { + if (printk_ratelimit()) + printk(KERN_ERR "can: request_module(%s)" + " failed.\n", module_name); + } + } + + spin_lock(&proto_tab_lock); + cp = proto_tab[protocol]; + if (cp && !try_module_get(cp->prot->owner)) + cp = NULL; + spin_unlock(&proto_tab_lock); + + /* check for available protocol and correct usage */ + + if (!cp) + return -EPROTONOSUPPORT; + + if (cp->type != sock->type) { + err = -EPROTONOSUPPORT; + goto errout; + } + + if (cp->capability >= 0 && !capable(cp->capability)) { + err = -EPERM; + 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: + module_put(cp->prot->owner); + 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!) + * + * 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 + */ +int can_send(struct sk_buff *skb, int loop) +{ + int err; + + if (skb->dev->type != ARPHRD_CAN) { + kfree_skb(skb); + return -EPERM; + } + + if (!(skb->dev->flags & IFF_UP)) { + kfree_skb(skb); + return -ENETDOWN; + } + + skb->protocol = htons(ETH_P_CAN); + 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. + */ + struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); + + if (!newskb) { + kfree_skb(skb); + return -ENOMEM; + } + + newskb->sk = skb->sk; + newskb->ip_summed = CHECKSUM_UNNECESSARY; + newskb->pkt_type = PACKET_BROADCAST; + netif_rx(newskb); + } + } 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); + + /* update statistics */ + can_stats.tx_frames++; + can_stats.tx_frames_delta++; + + return err; +} +EXPORT_SYMBOL(can_send); + +/* + * af_can rx path + */ + +static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev) +{ + struct dev_rcv_lists *d = NULL; + struct hlist_node *n; + + /* + * find receive list for this device + * + * The hlist_for_each_entry*() macros curse through the list + * using the pointer variable n and set d to the containing + * struct in each list iteration. Therefore, after list + * iteration, d is unmodified when the list is empty, and it + * points to last list element, when the list is non-empty + * but no match in the loop body is found. I.e. d is *not* + * NULL when no match is found. We can, however, use the + * cursor variable n to decide if a match was found. + */ + + hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) { + if (d->dev == dev) + break; + } + + return n ? d : NULL; +} + +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 error frames */ + if (*mask & CAN_ERR_FLAG) { + /* clear CAN_ERR_FLAG in list entry */ + *mask &= CAN_ERR_MASK; + return &d->rx[RX_ERR]; + } + + /* ensure valid values in can_mask */ + if (*mask & CAN_EFF_FLAG) + *mask &= (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG); + else + *mask &= (CAN_SFF_MASK | CAN_RTR_FLAG); + + /* 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]; + + /* use extra filterset for the subscription of exactly *ONE* can_id */ + if (*can_id & CAN_EFF_FLAG) { + if (*mask == (CAN_EFF_MASK | CAN_EFF_FLAG)) { + /* RFC: a use-case for hash-tables in the future? */ + return &d->rx[RX_EFF]; + } + } else { + if (*mask == CAN_SFF_MASK) + 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 indentification + * + * 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 frames (CAN_ERR_FLAG bit set in mask). + * + * 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) */ + + 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_device - rcu callback for dev_rcv_lists structure removal + */ +static void can_rx_delete_device(struct rcu_head *rp) +{ + struct dev_rcv_lists *d = container_of(rp, struct dev_rcv_lists, rcu); + + kfree(d); +} + +/* + * 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 hlist_node *next; + struct dev_rcv_lists *d; + + spin_lock(&can_rcvlists_lock); + + d = find_dev_rcv_lists(dev); + if (!d) { + printk(KERN_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, next, 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: + * If no matching list item was found, the list cursor variable next + * will be NULL, while r will point to the last item of the list. + */ + + if (!next) { + printk(KERN_ERR "BUG: receive list entry not found for " + "dev %s, id %03X, mask %03X\n", + DNAME(dev), can_id, mask); + r = NULL; + d = NULL; + 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) + hlist_del_rcu(&d->list); + else + d = NULL; + + out: + spin_unlock(&can_rcvlists_lock); + + /* schedule the receiver item for deletion */ + if (r) + call_rcu(&r->rcu, can_rx_delete_receiver); + + /* schedule the device structure for deletion */ + if (d) + call_rcu(&d->rcu, can_rx_delete_device); +} +EXPORT_SYMBOL(can_rx_unregister); + +static inline void deliver(struct sk_buff *skb, struct receiver *r) +{ + struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); + + if (clone) { + clone->sk = skb->sk; + r->func(clone, r->data); + r->matches++; + } +} + +static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb) +{ + struct receiver *r; + struct hlist_node *n; + 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 frame entries only */ + hlist_for_each_entry_rcu(r, n, &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, n, &d->rx[RX_ALL], list) { + deliver(skb, r); + matches++; + } + + /* check for can_id/mask entries */ + hlist_for_each_entry_rcu(r, n, &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, n, &d->rx[RX_INV], list) { + if ((can_id & r->mask) != r->can_id) { + deliver(skb, r); + matches++; + } + } + + /* check CAN_ID specific entries */ + if (can_id & CAN_EFF_FLAG) { + hlist_for_each_entry_rcu(r, n, &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, n, &d->rx_sff[can_id], list) { + deliver(skb, r); + matches++; + } + } + + return matches; +} + +static int can_rcv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev) +{ + struct dev_rcv_lists *d; + int matches; + + if (dev->type != ARPHRD_CAN || dev->nd_net != &init_net) { + kfree_skb(skb); + return 0; + } + + /* 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(); + + /* free the skbuff allocated by the netdevice driver */ + kfree_skb(skb); + + if (matches > 0) { + can_stats.matches++; + can_stats.matches_delta++; + } + + return 0; +} + +/* + * 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(struct can_proto *cp) +{ + int proto = cp->protocol; + int err = 0; + + if (proto < 0 || proto >= CAN_NPROTO) { + printk(KERN_ERR "can: protocol number %d out of range\n", + proto); + return -EINVAL; + } + + spin_lock(&proto_tab_lock); + if (proto_tab[proto]) { + printk(KERN_ERR "can: protocol %d already registered\n", + proto); + err = -EBUSY; + goto errout; + } + + err = proto_register(cp->prot, 0); + if (err < 0) + goto errout; + + proto_tab[proto] = cp; + + /* use generic ioctl function if the module doesn't bring its own */ + if (!cp->ops->ioctl) + cp->ops->ioctl = can_ioctl; + + errout: + spin_unlock(&proto_tab_lock); + + return err; +} +EXPORT_SYMBOL(can_proto_register); + +/** + * can_proto_unregister - unregister CAN transport protocol + * @cp: pointer to CAN protocol structure + */ +void can_proto_unregister(struct can_proto *cp) +{ + int proto = cp->protocol; + + spin_lock(&proto_tab_lock); + if (!proto_tab[proto]) { + printk(KERN_ERR "BUG: can: protocol %d is not registered\n", + proto); + } + proto_unregister(cp->prot); + proto_tab[proto] = NULL; + spin_unlock(&proto_tab_lock); +} +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 *data) +{ + struct net_device *dev = (struct net_device *)data; + struct dev_rcv_lists *d; + + if (dev->nd_net != &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 + * + * N.B. zeroing the struct is the correct initialization + * for the embedded hlist_head structs. + * Another list type, e.g. list_head, would require + * explicit initialization. + */ + + d = kzalloc(sizeof(*d), GFP_KERNEL); + if (!d) { + printk(KERN_ERR + "can: allocation of receive list failed\n"); + return NOTIFY_DONE; + } + d->dev = dev; + + spin_lock(&can_rcvlists_lock); + hlist_add_head_rcu(&d->list, &can_rx_dev_list); + spin_unlock(&can_rcvlists_lock); + + break; + + case NETDEV_UNREGISTER: + spin_lock(&can_rcvlists_lock); + + d = find_dev_rcv_lists(dev); + if (d) { + if (d->entries) { + d->remove_on_zero_entries = 1; + d = NULL; + } else + hlist_del_rcu(&d->list); + } else + printk(KERN_ERR "can: notifier: receive list not " + "found for dev %s\n", dev->name); + + spin_unlock(&can_rcvlists_lock); + + if (d) + call_rcu(&d->rcu, can_rx_delete_device); + + break; + } + + return NOTIFY_DONE; +} + +/* + * af_can module init/exit functions + */ + +static struct packet_type can_packet __read_mostly = { + .type = __constant_htons(ETH_P_CAN), + .dev = NULL, + .func = can_rcv, +}; + +static struct net_proto_family can_family_ops __read_mostly = { + .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) +{ + printk(banner); + + rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver), + 0, 0, NULL); + if (!rcv_cache) + return -ENOMEM; + + /* + * Insert can_rx_alldev_list for reception on all devices. + * This struct is zero initialized which is correct for the + * embedded hlist heads, the dev pointer, and the entries counter. + */ + + spin_lock(&can_rcvlists_lock); + hlist_add_head_rcu(&can_rx_alldev_list.list, &can_rx_dev_list); + spin_unlock(&can_rcvlists_lock); + + 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); + + return 0; +} + +static __exit void can_exit(void) +{ + struct dev_rcv_lists *d; + struct hlist_node *n, *next; + + if (stats_timer) + del_timer(&can_stattimer); + + can_remove_proc(); + + /* protocol unregister */ + dev_remove_pack(&can_packet); + unregister_netdevice_notifier(&can_netdev_notifier); + sock_unregister(PF_CAN); + + /* remove can_rx_dev_list */ + spin_lock(&can_rcvlists_lock); + hlist_del(&can_rx_alldev_list.list); + hlist_for_each_entry_safe(d, n, next, &can_rx_dev_list, list) { + hlist_del(&d->list); + kfree(d); + } + spin_unlock(&can_rcvlists_lock); + + kmem_cache_destroy(rcv_cache); +} + +module_init(can_init); +module_exit(can_exit); diff --git a/net/can/af_can.h b/net/can/af_can.h new file mode 100644 index 0000000..18f91e3 --- /dev/null +++ b/net/can/af_can.h @@ -0,0 +1,122 @@ +/* + * 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. + * + * Send feedback to <socketcan-users@lists.berlios.de> + * + */ + +#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 }; + +struct dev_rcv_lists { + struct hlist_node list; + struct rcu_head rcu; + struct net_device *dev; + 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; +}; + +/* function prototypes for the CAN networklayer procfs (proc.c) */ +extern void can_init_proc(void); +extern void can_remove_proc(void); +extern 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 */ diff --git a/net/can/proc.c b/net/can/proc.c new file mode 100644 index 0000000..520fef5 --- /dev/null +++ b/net/can/proc.c @@ -0,0 +1,533 @@ +/* + * 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. + * + * Send feedback to <socketcan-users@lists.berlios.de> + * + */ + +#include <linux/module.h> +#include <linux/proc_fs.h> +#include <linux/list.h> +#include <linux/rcupdate.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 + * + * From known use-cases we expect about 10 entries in a receive list to be + * printed in the proc_fs. So PAGE_SIZE is definitely enough space here. + * + */ + +static int can_print_rcvlist(char *page, int len, struct hlist_head *rx_list, + struct net_device *dev) +{ + struct receiver *r; + struct hlist_node *n; + + rcu_read_lock(); + hlist_for_each_entry_rcu(r, n, rx_list, list) { + char *fmt = (r->can_id & CAN_EFF_FLAG)? + " %-5s %08X %08x %08x %08x %8ld %s\n" : + " %-5s %03X %08x %08lx %08lx %8ld %s\n"; + + len += snprintf(page + len, PAGE_SIZE - len, fmt, + DNAME(dev), r->can_id, r->mask, + (unsigned long)r->func, (unsigned long)r->data, + r->matches, r->ident); + + /* does a typical line fit into the current buffer? */ + + /* 100 Bytes before end of buffer */ + if (len > PAGE_SIZE - 100) { + /* mark output cut off */ + len += snprintf(page + len, PAGE_SIZE - len, + " (..)\n"); + break; + } + } + rcu_read_unlock(); + + return len; +} + +static int can_print_recv_banner(char *page, int len) +{ + /* + * can1. 00000000 00000000 00000000 + * ....... 0 tp20 + */ + len += snprintf(page + len, PAGE_SIZE - len, + " device can_id can_mask function" + " userdata matches ident\n"); + + return len; +} + +static int can_proc_read_stats(char *page, char **start, off_t off, + int count, int *eof, void *data) +{ + int len = 0; + + len += snprintf(page + len, PAGE_SIZE - len, "\n"); + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld transmitted frames (TXF)\n", + can_stats.tx_frames); + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld received frames (RXF)\n", can_stats.rx_frames); + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld matched frames (RXMF)\n", can_stats.matches); + + len += snprintf(page + len, PAGE_SIZE - len, "\n"); + + if (can_stattimer.function == can_stat_update) { + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld %% total match ratio (RXMR)\n", + can_stats.total_rx_match_ratio); + + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld frames/s total tx rate (TXR)\n", + can_stats.total_tx_rate); + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld frames/s total rx rate (RXR)\n", + can_stats.total_rx_rate); + + len += snprintf(page + len, PAGE_SIZE - len, "\n"); + + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld %% current match ratio (CRXMR)\n", + can_stats.current_rx_match_ratio); + + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld frames/s current tx rate (CTXR)\n", + can_stats.current_tx_rate); + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld frames/s current rx rate (CRXR)\n", + can_stats.current_rx_rate); + + len += snprintf(page + len, PAGE_SIZE - len, "\n"); + + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld %% max match ratio (MRXMR)\n", + can_stats.max_rx_match_ratio); + + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld frames/s max tx rate (MTXR)\n", + can_stats.max_tx_rate); + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld frames/s max rx rate (MRXR)\n", + can_stats.max_rx_rate); + + len += snprintf(page + len, PAGE_SIZE - len, "\n"); + } + + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld current receive list entries (CRCV)\n", + can_pstats.rcv_entries); + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld maximum receive list entries (MRCV)\n", + can_pstats.rcv_entries_max); + + if (can_pstats.stats_reset) + len += snprintf(page + len, PAGE_SIZE - len, + "\n %8ld statistic resets (STR)\n", + can_pstats.stats_reset); + + if (can_pstats.user_reset) + len += snprintf(page + len, PAGE_SIZE - len, + " %8ld user statistic resets (USTR)\n", + can_pstats.user_reset); + + len += snprintf(page + len, PAGE_SIZE - len, "\n"); + + *eof = 1; + return len; +} + +static int can_proc_read_reset_stats(char *page, char **start, off_t off, + int count, int *eof, void *data) +{ + int len = 0; + + user_reset = 1; + + if (can_stattimer.function == can_stat_update) { + len += snprintf(page + len, PAGE_SIZE - len, + "Scheduled statistic reset #%ld.\n", + can_pstats.stats_reset + 1); + + } else { + if (can_stats.jiffies_init != jiffies) + can_init_stats(); + + len += snprintf(page + len, PAGE_SIZE - len, + "Performed statistic reset #%ld.\n", + can_pstats.stats_reset); + } + + *eof = 1; + return len; +} + +static int can_proc_read_version(char *page, char **start, off_t off, + int count, int *eof, void *data) +{ + int len = 0; + + len += snprintf(page + len, PAGE_SIZE - len, "%s\n", + CAN_VERSION_STRING); + *eof = 1; + return len; +} + +static int can_proc_read_rcvlist(char *page, char **start, off_t off, + int count, int *eof, void *data) +{ + /* double cast to prevent GCC warning */ + int idx = (int)(long)data; + int len = 0; + struct dev_rcv_lists *d; + struct hlist_node *n; + + len += snprintf(page + len, PAGE_SIZE - len, + "\nreceive list '%s':\n", rx_list_name[idx]); + + rcu_read_lock(); + hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) { + + if (!hlist_empty(&d->rx[idx])) { + len = can_print_recv_banner(page, len); + len = can_print_rcvlist(page, len, &d->rx[idx], d->dev); + } else + len += snprintf(page + len, PAGE_SIZE - len, + " (%s: no entry)\n", DNAME(d->dev)); + + /* exit on end of buffer? */ + if (len > PAGE_SIZE - 100) + break; + } + rcu_read_unlock(); + + len += snprintf(page + len, PAGE_SIZE - len, "\n"); + + *eof = 1; + return len; +} + +static int can_proc_read_rcvlist_sff(char *page, char **start, off_t off, + int count, int *eof, void *data) +{ + int len = 0; + struct dev_rcv_lists *d; + struct hlist_node *n; + + /* RX_SFF */ + len += snprintf(page + len, PAGE_SIZE - len, + "\nreceive list 'rx_sff':\n"); + + rcu_read_lock(); + hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) { + int i, all_empty = 1; + /* check wether 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) { + len = can_print_recv_banner(page, len); + for (i = 0; i < 0x800; i++) { + if (!hlist_empty(&d->rx_sff[i]) && + len < PAGE_SIZE - 100) + len = can_print_rcvlist(page, len, + &d->rx_sff[i], + d->dev); + } + } else + len += snprintf(page + len, PAGE_SIZE - len, + " (%s: no entry)\n", DNAME(d->dev)); + + /* exit on end of buffer? */ + if (len > PAGE_SIZE - 100) + break; + } + rcu_read_unlock(); + + len += snprintf(page + len, PAGE_SIZE - len, "\n"); + + *eof = 1; + return len; +} + +/* + * proc utility functions + */ + +static struct proc_dir_entry *can_create_proc_readentry(const char *name, + mode_t mode, + read_proc_t *read_proc, + void *data) +{ + if (can_dir) + return create_proc_read_entry(name, mode, can_dir, read_proc, + data); + else + return NULL; +} + +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; + } + + can_dir->owner = THIS_MODULE; + + /* own procfs entries from the AF_CAN core */ + pde_version = can_create_proc_readentry(CAN_PROC_VERSION, 0644, + can_proc_read_version, NULL); + pde_stats = can_create_proc_readentry(CAN_PROC_STATS, 0644, + can_proc_read_stats, NULL); + pde_reset_stats = can_create_proc_readentry(CAN_PROC_RESET_STATS, 0644, + can_proc_read_reset_stats, NULL); + pde_rcvlist_err = can_create_proc_readentry(CAN_PROC_RCVLIST_ERR, 0644, + can_proc_read_rcvlist, (void *)RX_ERR); + pde_rcvlist_all = can_create_proc_readentry(CAN_PROC_RCVLIST_ALL, 0644, + can_proc_read_rcvlist, (void *)RX_ALL); + pde_rcvlist_fil = can_create_proc_readentry(CAN_PROC_RCVLIST_FIL, 0644, + can_proc_read_rcvlist, (void *)RX_FIL); + pde_rcvlist_inv = can_create_proc_readentry(CAN_PROC_RCVLIST_INV, 0644, + can_proc_read_rcvlist, (void *)RX_INV); + pde_rcvlist_eff = can_create_proc_readentry(CAN_PROC_RCVLIST_EFF, 0644, + can_proc_read_rcvlist, (void *)RX_EFF); + pde_rcvlist_sff = can_create_proc_readentry(CAN_PROC_RCVLIST_SFF, 0644, + can_proc_read_rcvlist_sff, NULL); +} + +/* + * 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) + proc_net_remove(&init_net, "can"); +} |