[PATCH 4/7] CAN: Add broadcast manager (bcm) protocol

Urs Thuermann
2007-09-25T12:30:55Z

[-- Attachment #1: 04-can-bcm-proto.diff --]
[-- Type: text/plain, Size: 50108 bytes --]

This patch adds the CAN broadcast manager (bcm) protocol.

Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>

---
include/linux/can/bcm.h | 65 +
net/can/Kconfig | 13
net/can/Makefile | 3
net/can/bcm.c | 1778 ++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 1859 insertions(+)

Index: net-2.6.24/include/linux/can/bcm.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ net-2.6.24/include/linux/can/bcm.h 2007-09-25 13:31:23.000000000 +0200
@@ -0,0 +1,65 @@
+/*
+ * linux/can/bcm.h
+ *
+ * Definitions for CAN Broadcast Manager (BCM)
+ *
+ * Author: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Send feedback to <socketcan-users@lists.berlios.de>
+ *
+ */
+
+#ifndef CAN_BCM_H
+#define CAN_BCM_H
+
+/**
+ * struct bcm_msg_head - head of messages to/from the broadcast manager
+ * @opcode: opcode, see enum below.
+ * @flags: special flags, see below.
+ * @count: number of frames to send before changing interval.
+ * @ival1: interval for the first @count frames.
+ * @ival2: interval for the following frames.
+ * @can_id: CAN ID of frames to be sent or received.
+ * @nframes: number of frames appended to the message head.
+ * @frames: array of CAN frames.
+ */
+struct bcm_msg_head {
+ int opcode;
+ int flags;
+ int count;
+ struct timeval ival1, ival2;
+ canid_t can_id;
+ int nframes;
+ struct can_frame frames[0];
+};
+
+enum {
+ TX_SETUP = 1, /* create (cyclic) transmission task */
+ TX_DELETE, /* remove (cyclic) transmission task */
+ TX_READ, /* read properties of (cyclic) transmission task */
+ TX_SEND, /* send one CAN frame */
+ RX_SETUP, /* create RX content filter subscription */
+ RX_DELETE, /* remove RX content filter subscription */
+ RX_READ, /* read properties of RX content filter subscription */
+ TX_STATUS, /* reply to TX_READ request */
+ TX_EXPIRED, /* notification on performed transmissions (count=0) */
+ RX_STATUS, /* reply to RX_READ request */
+ RX_TIMEOUT, /* cyclic message is absent */
+ RX_CHANGED /* updated CAN frame (detected content change) */
+};
+
+#define SETTIMER 0x0001
+#define STARTTIMER 0x0002
+#define TX_COUNTEVT 0x0004
+#define TX_ANNOUNCE 0x0008
+#define TX_CP_CAN_ID 0x0010
+#define RX_FILTER_ID 0x0020
+#define RX_CHECK_DLC 0x0040
+#define RX_NO_AUTOTIMER 0x0080
+#define RX_ANNOUNCE_RESUME 0x0100
+#define TX_RESET_MULTI_IDX 0x0200
+#define RX_RTR_FRAME 0x0400
+
+#endif /* CAN_BCM_H */
Index: net-2.6.24/net/can/Kconfig
===================================================================
--- net-2.6.24.orig/net/can/Kconfig 2007-09-25 13:31:06.000000000 +0200
+++ net-2.6.24/net/can/Kconfig 2007-09-25 13:31:46.000000000 +0200
@@ -27,6 +27,19 @@
socket has several filter options e.g. ID-Masking / Errorframes.
To receive/send raw CAN messages, use AF_CAN with protocol CAN_RAW.

+config CAN_BCM
+ tristate "Broadcast Manager CAN Protocol (with content filtering)"
+ depends on CAN
+ default N
+ ---help---
+ The Broadcast Manager offers content filtering, timeout monitoring,
+ sending of RTR-frames and cyclic CAN messages without permanent user
+ interaction. The BCM can be 'programmed' via the BSD socket API and
+ informs you on demand e.g. only on content updates / timeouts.
+ You probably want to use the bcm socket in most cases where cyclic
+ CAN messages are used on the bus (e.g. in automotive environments).
+ To use the Broadcast Manager, use AF_CAN with protocol CAN_BCM.
+
config CAN_DEBUG_CORE
bool "CAN Core debugging messages"
depends on CAN
Index: net-2.6.24/net/can/Makefile
===================================================================
--- net-2.6.24.orig/net/can/Makefile 2007-09-25 13:29:23.000000000 +0200
+++ net-2.6.24/net/can/Makefile 2007-09-25 13:31:23.000000000 +0200
@@ -7,3 +7,6 @@

obj-$(CONFIG_CAN_RAW) += can-raw.o
can-raw-objs := raw.o
+
+obj-$(CONFIG_CAN_BCM) += can-bcm.o
+can-bcm-objs := bcm.o
Index: net-2.6.24/net/can/bcm.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ net-2.6.24/net/can/bcm.c 2007-09-25 13:31:23.000000000 +0200
@@ -0,0 +1,1778 @@
+/*
+ * 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, the following disclaimer and
+ * the referenced file 'COPYING'.
+ * 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 as distributed in the 'COPYING'
+ * file from the main directory of the linux kernel source.
+ *
+ * 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/list.h>
+#include <linux/proc_fs.h>
+#include <linux/uio.h>
+#include <linux/poll.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/bcm.h>
+#include <net/sock.h>
+#include <net/net_namespace.h>
+
+/* 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_RTR_FLAG) | ((id & CAN_EFF_FLAG) ? \
+ (CAN_EFF_MASK | CAN_EFF_FLAG) : CAN_SFF_MASK))
+
+#define IDENT "bcm"
+#define CAN_BCM_VERSION CAN_VERSION
+static __initdata const char banner[] = KERN_INFO
+ "can: broadcast manager protocol (rev " CAN_BCM_VERSION ")\n";
+
+MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
+
+#ifdef CONFIG_CAN_DEBUG_CORE
+static int debug;
+module_param(debug, int, S_IRUGO);
+MODULE_PARM_DESC(debug, "debug print mask: 1:debug, 2:frames, 4:skbs");
+#endif
+
+/* 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;
+ int flags;
+ unsigned long j_ival1, j_ival2, j_lastmsg;
+ unsigned long frames_abs, frames_filtered;
+ struct timer_list timer, thrtimer;
+ struct timeval ival1, ival2;
+ ktime_t rx_stamp;
+ int rx_ifindex;
+ int count;
+ int nframes;
+ int 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 [9]; /* pointer printed in ASCII 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)
+
+/*
+ * rounded_tv2jif - calculate jiffies from timeval including optional up
+ * @tv: pointer to timeval
+ *
+ * Description:
+ * Unlike timeval_to_jiffies() provided in include/linux/jiffies.h, this
+ * function is intentionally more relaxed on precise timer ticks to get
+ * exact one jiffy for requested 1000us on a 1000HZ machine.
+ * This code is to be removed when upgrading to kernel hrtimer.
+ *
+ * Return:
+ * calculated jiffies (max: ULONG_MAX)
+ */
+static unsigned long rounded_tv2jif(const struct timeval *tv)
+{
+ unsigned long sec = tv->tv_sec;
+ unsigned long usec = tv->tv_usec;
+ unsigned long jif;
+
+ if (sec > ULONG_MAX / HZ)
+ return ULONG_MAX;
+
+ /* round up to get at least the requested time */
+ usec += 1000000 / HZ - 1;
+
+ jif = usec / (1000000 / HZ);
+
+ if (sec * HZ > ULONG_MAX - jif)
+ return ULONG_MAX;
+
+ return jif + sec * HZ;
+}
+
+/*
+ * procfs functions
+ */
+static char *bcm_proc_getifname(int ifindex)
+{
+ struct net_device *dev;
+
+ if (!ifindex)
+ return "any";
+
+ dev = __dev_get_by_index(&init_net, ifindex); /* no usage counting */
+ if (dev)
+ return dev->name;
+
+ return "???";
+}
+
+static int bcm_read_proc(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ int len = 0;
+ struct sock *sk = (struct sock *)data;
+ struct bcm_sock *bo = bcm_sk(sk);
+ struct bcm_op *op;
+
+ len += snprintf(page + len, PAGE_SIZE - len, ">>> socket %p",
+ sk->sk_socket);
+ len += snprintf(page + len, PAGE_SIZE - len, " / sk %p", sk);
+ len += snprintf(page + len, PAGE_SIZE - len, " / bo %p", bo);
+ len += snprintf(page + len, PAGE_SIZE - len, " / dropped %lu",
+ bo->dropped_usr_msgs);
+ len += snprintf(page + len, PAGE_SIZE - len, " / bound %s",
+ bcm_proc_getifname(bo->ifindex));
+ len += snprintf(page + len, PAGE_SIZE - len, " <<<\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;
+
+ len += snprintf(page + len, PAGE_SIZE - len,
+ "rx_op: %03X %-5s ",
+ op->can_id, bcm_proc_getifname(op->ifindex));
+ len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ",
+ op->nframes,
+ (op->flags & RX_CHECK_DLC)?'d':' ');
+ if (op->j_ival1)
+ len += snprintf(page + len, PAGE_SIZE - len,
+ "timeo=%ld ", op->j_ival1);
+
+ if (op->j_ival2)
+ len += snprintf(page + len, PAGE_SIZE - len,
+ "thr=%ld ", op->j_ival2);
+
+ len += snprintf(page + len, PAGE_SIZE - len,
+ "# recv %ld (%ld) => reduction: ",
+ op->frames_filtered, op->frames_abs);
+
+ reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
+
+ len += snprintf(page + len, PAGE_SIZE - len, "%s%ld%%\n",
+ (reduction == 100)?"near ":"", reduction);
+
+ if (len > PAGE_SIZE - 200) {
+ /* mark output cut off */
+ len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
+ break;
+ }
+ }
+
+ list_for_each_entry(op, &bo->tx_ops, list) {
+
+ len += snprintf(page + len, PAGE_SIZE - len,
+ "tx_op: %03X %s [%d] ",
+ op->can_id, bcm_proc_getifname(op->ifindex),
+ op->nframes);
+ if (op->j_ival1)
+ len += snprintf(page + len, PAGE_SIZE - len, "t1=%ld ",
+ op->j_ival1);
+
+ if (op->j_ival2)
+ len += snprintf(page + len, PAGE_SIZE - len, "t2=%ld ",
+ op->j_ival2);
+
+ len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n",
+ op->frames_abs);
+
+ if (len > PAGE_SIZE - 100) {
+ /* mark output cut off */
+ len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
+ break;
+ }
+ }
+
+ len += snprintf(page + len, PAGE_SIZE - len, "\n");
+
+ *eof = 1;
+ return len;
+}
+
+/*
+ * 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];
+
+ DBG_FRAME("BCM: bcm_can_tx: sending frame", cf);
+
+ /* 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,
+ in_interrupt() ? GFP_ATOMIC : GFP_KERNEL);
+
+ if (!skb)
+ goto out;
+
+ memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
+
+ /* send with loopback */
+ skb->dev = dev;
+ skb->sk = 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;
+ int datalen = head->nframes * CFSIZ;
+ int err;
+
+ skb = alloc_skb(sizeof(*head) + datalen,
+ in_interrupt() ? GFP_ATOMIC : GFP_KERNEL);
+ 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);
+
+ DBG("sock_queue_rcv_skb failed: %d\n", err);
+ kfree_skb(skb);
+ /* don't care about overflows in this statistic */
+ bo->dropped_usr_msgs++;
+ }
+}
+
+/*
+ * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
+ */
+static void bcm_tx_timeout_handler(unsigned long data)
+{
+ struct bcm_op *op = (struct bcm_op *)data;
+
+ DBG("Called with bcm_op %p\n", op);
+
+ if (op->j_ival1 && (op->count > 0)) {
+
+ op->count--;
+ if (!op->count && (op->flags & TX_COUNTEVT)) {
+ struct bcm_msg_head msg_head;
+
+ /* create notification to user */
+ DBG("sending TX_EXPIRED for can_id %03X\n",
+ op->can_id);
+
+ 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);
+ }
+ }
+
+ DBG("count=%d j_ival1=%ld j_ival2=%ld\n",
+ op->count, op->j_ival1, op->j_ival2);
+
+ if (op->j_ival1 && (op->count > 0)) {
+
+ op->timer.expires = jiffies + op->j_ival1;
+ add_timer(&op->timer);
+
+ DBG("adding timer ival1. func=%p data=%p exp=0x%08X\n",
+ op->timer.function,
+ (char *) op->timer.data,
+ (unsigned int) op->timer.expires);
+
+ /* send (next) frame */
+ bcm_can_tx(op);
+
+ } else {
+ if (op->j_ival2) {
+ op->timer.expires = jiffies + op->j_ival2;
+ add_timer(&op->timer);
+
+ DBG("adding timer ival2. func=%p data=%p exp=0x%08X\n",
+ op->timer.function,
+ (char *) op->timer.data,
+ (unsigned int) op->timer.expires);
+
+ /* send (next) frame */
+ bcm_can_tx(op);
+
+ } else
+ DBG("no timer restart\n");
+ }
+
+ return;
+}
+
+/*
+ * 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;
+
+ op->j_lastmsg = jiffies;
+
+ /* update statistics */
+ op->frames_filtered++;
+
+ /* prevent statistics overflow */
+ if (op->frames_filtered > ULONG_MAX/100)
+ op->frames_filtered = op->frames_abs = 0;
+
+ DBG("setting j_lastmsg to 0x%08X for rx_op %p\n",
+ (unsigned int) op->j_lastmsg, op);
+ DBG("sending notification\n");
+
+ 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,
+ struct can_frame *rxdata)
+{
+ unsigned long nexttx = op->j_lastmsg + op->j_ival2;
+
+ memcpy(lastdata, rxdata, CFSIZ);
+
+ /* mark as used */
+ lastdata->can_dlc |= RX_RECV;
+
+ /* throttle bcm_rx_changed ? */
+ if ((op->thrtimer.expires) ||
+ ((op->j_ival2) && (nexttx > jiffies))) {
+ /* we are already waiting OR we have to start waiting */
+
+ /* mark as 'throttled' */
+ lastdata->can_dlc |= RX_THR;
+
+ if (!(op->thrtimer.expires)) {
+ /* start the timer only the first time */
+ op->thrtimer.expires = nexttx;
+ add_timer(&op->thrtimer);
+
+ DBG("adding thrtimer. func=%p data=%p exp=0x%08X\n",
+ op->thrtimer.function,
+ (char *) op->thrtimer.data,
+ (unsigned int) op->thrtimer.expires);
+ }
+
+ } else {
+ /* send RX_CHANGED to the user immediately */
+ bcm_rx_changed(op, rxdata);
+ }
+}
+
+/*
+ * 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, int index,
+ 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 */
+ DBG("first time :)\n");
+ bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
+ return;
+ }
+
+ /* do a real check in can_frame data section */
+
+ DBG("op->frames[index].data = 0x%016llx\n",
+ GET_U64(&op->frames[index]));
+ DBG("op->last_frames[index].data = 0x%016llx\n",
+ GET_U64(&op->last_frames[index]));
+ DBG("rxdata->data = 0x%016llx\n", GET_U64(rxdata));
+
+ if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
+ (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
+ DBG("relevant data change :)\n");
+ 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)) {
+ DBG("dlc change :)\n");
+ bcm_rx_update_and_send(op, &op->last_frames[index],
+ rxdata);
+ return;
+ }
+ }
+ DBG("no relevant change :(\n");
+}
+
+/*
+ * 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->j_ival1) {
+ op->timer.expires = jiffies + op->j_ival1;
+
+ DBG("adding rx timeout timer ival1. func=%p data=%p "
+ "exp=0x%08X\n",
+ op->timer.function,
+ (char *) op->timer.data,
+ (unsigned int) op->timer.expires);
+
+ add_timer(&op->timer);
+ }
+}
+
+/*
+ * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
+ */
+static void bcm_rx_timeout_handler(unsigned long data)
+{
+ struct bcm_op *op = (struct bcm_op *)data;
+ struct bcm_msg_head msg_head;
+
+ DBG("sending RX_TIMEOUT for can_id %03X. op is %p\n", op->can_id, op);
+
+ 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);
+
+ /* 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);
+ DBG("RX_ANNOUNCE_RESTART\n");
+ }
+}
+
+/*
+ * bcm_rx_thr_handler - the time for blocked content updates is over now:
+ * Check for throttled data and send it to the userspace
+ */
+static void bcm_rx_thr_handler(unsigned long data)
+{
+ struct bcm_op *op = (struct bcm_op *)data;
+ int i = 0;
+
+ /* mark disabled / consumed timer */
+ op->thrtimer.expires = 0;
+
+ if (op->nframes > 1) {
+ DBG("sending MUX RX_CHANGED for can_id %03X. op is %p\n",
+ op->can_id, op);
+ /* for MUX filter we start at index 1 */
+ for (i = 1; i < op->nframes; i++) {
+ if ((op->last_frames) &&
+ (op->last_frames[i].can_dlc & RX_THR)) {
+ op->last_frames[i].can_dlc &= ~RX_THR;
+ bcm_rx_changed(op, &op->last_frames[i]);
+ }
+ }
+
+ } else {
+ DBG("sending simple RX_CHANGED for can_id %03X. op is %p\n",
+ op->can_id, op);
+ /* for RX_FILTER_ID and simple filter */
+ if (op->last_frames && (op->last_frames[0].can_dlc & RX_THR)) {
+ op->last_frames[0].can_dlc &= ~RX_THR;
+ bcm_rx_changed(op, &op->last_frames[0]);
+ }
+ }
+}
+
+/*
+ * 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;
+ struct can_frame rxframe;
+ int i;
+
+ /* disable timeout */
+ del_timer(&op->timer);
+
+ DBG("Called with bcm_op %p\n", op);
+
+ if (skb->len == sizeof(rxframe)) {
+ memcpy(&rxframe, skb->data, sizeof(rxframe));
+ /* save rx timestamp */
+ op->rx_stamp = skb->tstamp;
+ /* save originator for recvfrom() */
+ op->rx_ifindex = skb->dev->ifindex;
+ /* update statistics */
+ op->frames_abs++;
+ kfree_skb(skb);
+ DBG("got can_frame with can_id %03X\n", rxframe.can_id);
+
+ } else {
+ DBG("Wrong skb->len = %d\n", skb->len);
+ kfree_skb(skb);
+ return;
+ }
+
+ DBG_FRAME("BCM: bcm_rx_handler: CAN frame", &rxframe);
+
+ if (op->can_id != rxframe.can_id) {
+ DBG("ERROR! Got wrong can_id %03X! Expected %03X.\n",
+ rxframe.can_id, op->can_id);
+ return;
+ }
+
+ if (op->flags & RX_RTR_FRAME) {
+ /* send reply for RTR-request */
+ DBG("RTR-request\n");
+
+ /* send op->frames[0] to CAN device */
+ bcm_can_tx(op);
+ return;
+ }
+
+ if (op->flags & RX_FILTER_ID) {
+ /* the easiest case */
+ DBG("Easy does it with RX_FILTER_ID\n");
+
+ bcm_rx_update_and_send(op, &op->last_frames[0], &rxframe);
+ bcm_rx_starttimer(op);
+ return;
+ }
+
+ if (op->nframes == 1) {
+ /* simple compare with index 0 */
+ DBG("Simple compare\n");
+
+ bcm_rx_cmp_to_index(op, 0, &rxframe);
+ bcm_rx_starttimer(op);
+ return;
+ }
+
+ if (op->nframes > 1) {
+ /* multiplex compare */
+ DBG("Multiplex compare\n");
+
+ /*
+ * 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]))) {
+ DBG("found MUX index %d\n", i);
+ bcm_rx_cmp_to_index(op, i, &rxframe);
+ break;
+ }
+ }
+ 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)
+{
+ del_timer(&op->timer);
+ del_timer(&op->thrtimer);
+
+ 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);
+
+ return;
+}
+
+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)) {
+ DBG("removing rx_op %p for can_id %03X\n",
+ op, op->can_id);
+
+ /*
+ * 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)) {
+ DBG("removing rx_op %p for can_id %03X\n",
+ op, op->can_id);
+ 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) {
+ DBG("TRX_READ: did not find op for can_id %03X\n",
+ msg_head->can_id);
+ return -EINVAL;
+ }
+
+ DBG("TRX_READ: sending status for can_id %03X\n",
+ msg_head->can_id);
+ /* 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;
+ int i, err;
+
+ /* we need a real device to send frames */
+ if (!ifindex)
+ return -ENODEV;
+
+ /* we need at least one can_frame */
+ if (msg_head->nframes < 1)
+ 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 */
+
+ DBG("TX_SETUP: modifying existing tx_op %p for can_id %03X\n",
+ op, msg_head->can_id);
+
+ /*
+ * 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 (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;
+
+ DBG("TX_SETUP: creating new tx_op %p for can_id %03X\n",
+ op, msg_head->can_id);
+
+ 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 (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 (kmalloc) structure */
+ init_timer(&op->timer);
+
+ /* currently unused in tx_ops */
+ init_timer(&op->thrtimer);
+
+ /* handler for tx_ops */
+ op->timer.function = bcm_tx_timeout_handler;
+
+ /* timer.data points to this op-structure */
+ op->timer.data = (unsigned long)op;
+
+ /* 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->j_ival1 = rounded_tv2jif(&msg_head->ival1);
+ op->j_ival2 = rounded_tv2jif(&msg_head->ival2);
+
+ DBG("TX_SETUP: SETTIMER count=%d j_ival1=%ld j_ival2=%ld\n",
+ op->count, op->j_ival1, op->j_ival2);
+
+ /* disable an active timer due to zero values? */
+ if (!op->j_ival1 && !op->j_ival2) {
+ del_timer(&op->timer);
+ DBG("TX_SETUP: SETTIMER disabled timer.\n");
+ }
+ }
+
+ if ((op->flags & STARTTIMER) &&
+ ((op->j_ival1 && op->count) || op->j_ival2)) {
+
+ del_timer(&op->timer);
+
+ /* spec: send can_frame when starting timer */
+ op->flags |= TX_ANNOUNCE;
+
+ if (op->j_ival1 && (op->count > 0)) {
+ op->timer.expires = jiffies + op->j_ival1;
+ /* op->count-- is done in bcm_tx_timeout_handler */
+ DBG("TX_SETUP: adding timer ival1. func=%p data=%p "
+ "exp=0x%08X\n",
+ op->timer.function,
+ (char *) op->timer.data,
+ (unsigned int) op->timer.expires);
+
+ } else {
+ op->timer.expires = jiffies + op->j_ival2;
+ DBG("TX_SETUP: adding timer ival2. func=%p data=%p "
+ "exp=0x%08X\n",
+ op->timer.function,
+ (char *) op->timer.data,
+ (unsigned int) op->timer.expires);
+ }
+
+ add_timer(&op->timer);
+ }
+
+ if (op->flags & TX_ANNOUNCE)
+ bcm_can_tx(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;
+ msg_head->nframes = 0; /* ignore trailing garbage */
+ }
+
+ if ((msg_head->flags & RX_RTR_FRAME) &&
+ ((msg_head->nframes != 1) ||
+ (!(msg_head->can_id & CAN_RTR_FLAG)))) {
+
+ DBG("RX_SETUP: bad RX_RTR_FRAME setup!\n");
+ 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 */
+
+ DBG("RX_SETUP: modifying existing rx_op %p for can_id %03X\n",
+ op, msg_head->can_id);
+
+ /*
+ * 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;
+
+ DBG("RX_SETUP: creating new rx_op %p for can_id %03X\n",
+ op, msg_head->can_id);
+
+ 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;
+ }
+ }
+
+ op->sk = sk;
+ op->ifindex = ifindex;
+
+ /* initialize uninitialized (kzalloc) structure */
+ init_timer(&op->timer);
+
+ /* init throttle timer for RX_CHANGED */
+ init_timer(&op->thrtimer);
+
+ /* handler for rx timeouts */
+ op->timer.function = bcm_rx_timeout_handler;
+
+ /* timer.data points to this op-structure */
+ op->timer.data = (unsigned long)op;
+
+ /* handler for RX_CHANGED throttle timeouts */
+ op->thrtimer.function = bcm_rx_thr_handler;
+
+ /* timer.data points to this op-structure */
+ op->thrtimer.data = (unsigned long)op;
+
+ /* mark disabled timer */
+ op->thrtimer.expires = 0;
+
+ /* 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 */
+ del_timer(&op->thrtimer);
+ del_timer(&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->j_ival1 = rounded_tv2jif(&msg_head->ival1);
+ op->j_ival2 = rounded_tv2jif(&msg_head->ival2);
+
+ DBG("RX_SETUP: SETTIMER j_ival1=%ld j_ival2=%ld\n",
+ op->j_ival1, op->j_ival2);
+
+ /* disable an active timer due to zero value? */
+ if (!op->j_ival1) {
+ del_timer(&op->timer);
+ DBG("RX_SETUP: disabled timer rx timeouts.\n");
+ }
+
+ /* free currently blocked msgs ? */
+ if (op->thrtimer.expires) {
+ DBG("RX_SETUP: unblocking throttled msgs.\n");
+ del_timer(&op->thrtimer);
+ /* send blocked msgs hereafter */
+ op->thrtimer.expires = jiffies + 2;
+ add_timer(&op->thrtimer);
+ }
+ /*
+ * if (op->j_ival2) is zero, no (new) throttling
+ * will happen. For details see functions
+ * bcm_rx_update_and_send() and bcm_rx_thr_handler()
+ */
+ }
+
+ if ((op->flags & STARTTIMER) && op->j_ival1) {
+
+ del_timer(&op->timer);
+ op->timer.expires = jiffies + op->j_ival1;
+
+ DBG("RX_SETUP: adding timer ival1. func=%p data=%p"
+ " exp=0x%08X\n",
+ (char *) op->timer.function,
+ (char *) op->timer.data,
+ (unsigned int) op->timer.expires);
+
+ add_timer(&op->timer);
+ }
+ }
+
+ /* now we can register for can_ids, if we added a new bcm_op */
+ if (do_rx_register) {
+ DBG("RX_SETUP: can_rx_register() for can_id %03X. "
+ "rx_op is %p\n", op->can_id, op);
+
+ 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,
+ IDENT);
+
+ 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, IDENT);
+ 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;
+
+ /* just copy and send one can_frame */
+
+ if (!ifindex) /* we need a real device to send frames */
+ return -ENODEV;
+
+ skb = alloc_skb(CFSIZ, GFP_KERNEL);
+
+ if (!skb)
+ return -ENOMEM;
+
+ err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
+ if (err < 0) {
+ kfree_skb(skb);
+ return err;
+ }
+
+ DBG_FRAME("BCM: TX_SEND: sending frame",
+ (struct can_frame *)skb->data);
+
+ dev = dev_get_by_index(&init_net, ifindex);
+ if (!dev) {
+ kfree_skb(skb);
+ return -ENODEV;
+ }
+
+ skb->dev = dev;
+ skb->sk = sk;
+ can_send(skb, 1); /* send with loopback */
+ dev_put(dev);
+
+ 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) {
+ DBG("sock %p not bound\n", sk);
+ return -ENOTCONN;
+ }
+
+ /* check for alternative ifindex for this bcm_op */
+
+ if (!ifindex && msg->msg_name) {
+ /* no bound device as default => check msg_name */
+ struct sockaddr_can *addr =
+ (struct sockaddr_can *)msg->msg_name;
+
+ if (addr->can_family != AF_CAN)
+ return -EINVAL;
+
+ ifindex = addr->can_ifindex; /* ifindex from sendto() */
+
+ if (ifindex) {
+ struct net_device *dev;
+
+ dev = dev_get_by_index(&init_net, ifindex);
+ if (!dev) {
+ DBG("device %d not found\n", ifindex);
+ return -ENODEV;
+ }
+
+ if (dev->type != ARPHRD_CAN) {
+ DBG("device %d no CAN device\n", ifindex);
+ 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;
+
+ DBG("opcode %d for can_id %03X\n", msg_head.opcode, msg_head.can_id);
+
+ 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 at least one can_frame */
+ if (msg_head.nframes < 1)
+ ret = -EINVAL;
+ else
+ ret = bcm_tx_send(msg, ifindex, sk);
+ break;
+
+ default:
+ DBG("Unknown opcode %d\n", msg_head.opcode);
+ 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 *data)
+{
+ struct net_device *dev = (struct net_device *)data;
+ struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
+ struct sock *sk = &bo->sk;
+ struct bcm_op *op;
+ int notify_enodev = 0;
+
+ DBG("msg %ld for dev %p (%s idx %d) sk %p bo->ifindex %d\n",
+ msg, dev, dev->name, dev->ifindex, sk, bo->ifindex);
+
+ if (dev->nd_net != &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 = bcm_sk(sk);
+ struct bcm_op *op, *next;
+
+ DBG("socket %p, sk %p\n", sock, 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) {
+ DBG("removing tx_op %p for can_id %03X\n", op, op->can_id);
+ bcm_remove_op(op);
+ }
+
+ list_for_each_entry_safe(op, next, &bo->rx_ops, list) {
+ DBG("removing rx_op %p for can_id %03X\n", op, op->can_id);
+
+ /*
+ * 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;
+ }
+
+ 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 (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) {
+ DBG("could not find device index %d\n",
+ addr->can_ifindex);
+ return -ENODEV;
+ }
+
+ if (dev->type != ARPHRD_CAN) {
+ DBG("device %d no CAN device\n", addr->can_ifindex);
+ dev_put(dev);
+ return -ENODEV;
+ }
+
+ bo->ifindex = dev->ifindex;
+ dev_put(dev);
+
+ DBG("socket %p bound to device %s (idx %d)\n",
+ sock, dev->name, dev->ifindex);
+
+ } 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, "%p", sock);
+ bo->bcm_proc_read = create_proc_read_entry(bo->procname, 0644,
+ proc_dir,
+ bcm_read_proc, 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;
+
+ DBG("socket %p, sk %p\n", sock, sk);
+
+ noblock = flags & MSG_DONTWAIT;
+ flags &= ~MSG_DONTWAIT;
+ skb = skb_recv_datagram(sk, flags, noblock, &error);
+ if (!skb)
+ return error;
+
+ DBG("delivering skbuff %p\n", skb);
+ DBG_SKB(skb);
+
+ 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_timestamp(msg, sk, skb);
+
+ if (msg->msg_name) {
+ msg->msg_namelen = sizeof(struct sockaddr_can);
+ memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
+ }
+
+ DBG("freeing sock %p, skbuff %p\n", sk, skb);
+ skb_free_datagram(sk, skb);
+
+ return size;
+}
+
+static unsigned int bcm_poll(struct file *file, struct socket *sock,
+ poll_table *wait)
+{
+ unsigned int mask = 0;
+
+ DBG("socket %p\n", sock);
+
+ mask = datagram_poll(file, sock, wait);
+ return mask;
+}
+
+static struct proto_ops bcm_ops __read_mostly = {
+ .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 = bcm_poll,
+ .ioctl = NULL, /* 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 struct can_proto bcm_can_proto __read_mostly = {
+ .type = SOCK_DGRAM,
+ .protocol = CAN_BCM,
+ .capability = -1,
+ .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-"IDENT, init_net.proc_net);
+
+ if (proc_dir)
+ proc_dir->owner = THIS_MODULE;
+
+ return 0;
+}
+
+static void __exit bcm_module_exit(void)
+{
+ can_proto_unregister(&bcm_can_proto);
+
+ if (proc_dir)
+ proc_net_remove(&init_net, "can-"IDENT);
+}
+
+module_init(bcm_module_init);
+module_exit(bcm_module_exit);

--