cregit-Linux how code gets into the kernel

Release 4.11 net/can/bcm.c

Directory: net/can
/*
 * bcm.c - Broadcast Manager to filter/send (cyclic) CAN content
 *
 * Copyright (c) 2002-2016 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].flags */

#define RX_RECV    0x40 
/* received data for this element */

#define RX_THR     0x80 
/* element not been sent due to throttle feature */

#define BCM_CAN_FLAGS_MASK 0x3F 
/* to clean private flags after usage */

/* 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 "20161123"

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 the first 64 bit of can(fd)_frame payload. cp->data is
 * 64 bit aligned so the offset has to be multiples of 8 which is ensured
 * by the only callers in bcm_rx_cmp_to_index() bcm_rx_handler().
 */



static inline u64 get_u64(const struct canfd_frame *cp, int offset)
{
	return *(u64 *)(cp->data + offset);
}


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Total30100.00%2100.00%




struct bcm_op {
	
struct list_head list;
	
int ifindex;
	
canid_t can_id;
	
u32 flags;
	

unsigned long frames_abs, frames_filtered;
	

struct bcm_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;
	
int cfsiz;
	
u32 count;
	
u32 nframes;
	
u32 currframe;
	/* void pointers to arrays of struct can[fd]_frame */
	
void *frames;
	
void *last_frames;
	
struct canfd_frame sframe;
	
struct canfd_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;
}


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static inline ktime_t bcm_timeval_to_ktime(struct bcm_timeval tv)
{
	return ktime_set(tv.tv_sec, tv.tv_usec * NSEC_PER_USEC);
}


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#define CFSIZ(flags) ((flags & CAN_FD_FRAME) ? CANFD_MTU : CAN_MTU)

#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;
}


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Oliver Hartkopp4161.19%133.33%


Eric Dumazet2131.34%133.33%


Stephen Hemminger57.46%133.33%


Total67100.00%3100.00%






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));

		if (op->flags & CAN_FD_FRAME)
			seq_printf(m, "(%u)", op->nframes);
		else
			seq_printf(m, "[%u]", op->nframes);

		seq_printf(m, "%c ", (op->flags & RX_CHECK_DLC) ? 'd' : ' ');

		if (op->kt_ival1)
			seq_printf(m, "timeo=%lld ",
				   (long long)ktime_to_us(op->kt_ival1));

		if (op->kt_ival2)
			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 ", op->can_id,
			   bcm_proc_getifname(ifname, op->ifindex));

		if (op->flags & CAN_FD_FRAME)
			seq_printf(m, "(%u) ", op->nframes);
		else
			seq_printf(m, "[%u] ", op->nframes);

		if (op->kt_ival1)
			seq_printf(m, "t1=%lld ",
				   (long long)ktime_to_us(op->kt_ival1));

		if (op->kt_ival2)
			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;
}


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Oliver Hartkopp37285.71%350.00%


Alexey Dobriyan4710.83%116.67%


Eric Dumazet122.76%116.67%


Dan Rosenberg30.69%116.67%


Total434100.00%6100.00%






static int bcm_proc_open(struct inode *inode, struct file *file)
{
	return single_open(file, bcm_proc_show, PDE_DATA(inode));
}


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Alexey Dobriyan2275.86%133.33%


Oliver Hartkopp620.69%133.33%


Al Viro13.45%133.33%


Total29100.00%3100.00%




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 canfd_frame *cf = op->frames + op->cfsiz * 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(op->cfsiz + sizeof(struct can_skb_priv), gfp_any());
	if (!skb)
		goto out;

	can_skb_reserve(skb);
	can_skb_prv(skb)->ifindex = dev->ifindex;
	can_skb_prv(skb)->skbcnt = 0;

	memcpy(skb_put(skb, op->cfsiz), cf, op->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);
}


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Oliver Hartkopp195100.00%6100.00%


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/*
 * 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 canfd_frame *frames, int has_timestamp)
{
	struct sk_buff *skb;
	struct canfd_frame *firstframe;
	struct sockaddr_can *addr;
	struct sock *sk = op->sk;
	unsigned int datalen = head->nframes * op->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 canfd_frame *)skb_tail_pointer(skb);

		memcpy(skb_put(skb, datalen), frames, datalen);

		/*
                 * the BCM uses the flags-element of the canfd_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->flags &= BCM_CAN_FLAGS_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.
         */

	sock_skb_cb_check_size(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++;
	}
}


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Oliver Hartkopp25799.61%480.00%


Eyal Birger10.39%120.00%


Total258100.00%5100.00%






static void bcm_tx_start_timer(struct bcm_op *op)
{
	if (op->kt_ival1 && op->count)
		hrtimer_start(&op->timer,
			      ktime_add(ktime_get(), op->kt_ival1),
			      HRTIMER_MODE_ABS);
	else if (op->kt_ival2)
		hrtimer_start(&op->timer,
			      ktime_add(ktime_get(), op->kt_ival2),
			      HRTIMER_MODE_ABS);
}


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Oliver Hartkopp68100.00%1100.00%


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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 && (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)
		bcm_can_tx(op);

	bcm_tx_start_timer(op);
}


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/*
 * 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;
}


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/*
 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
 */



static void bcm_rx_changed(struct bcm_op *op, struct canfd_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->flags &= (BCM_CAN_FLAGS_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);
}


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/*
 * 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 canfd_frame *lastdata,
				   const struct canfd_frame *rxdata)
{
	memcpy(lastdata, rxdata, op->cfsiz);

	/* mark as used and throttled by default */
	lastdata->flags |= (RX_RECV|RX_THR);

	/* throttling mode inactive ? */
	if (!op->kt_ival2) {
		/* 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 reception with enabled throttling mode */
	if (!op->kt_lastmsg)
		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();
}


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Jeremiah Mahler21.35%120.00%


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/*
 * 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 canfd_frame *rxdata)
{
	struct canfd_frame *cf = op->frames + op->cfsiz * index;
	struct canfd_frame *lcf = op->last_frames + op->cfsiz * index;
	int i;

	/*
         * no one uses the MSBs of flags for comparison,
         * so we use it here to detect the first time of reception
         */

	if (!(lcf->flags & RX_RECV)) {
		/* received data for the first time => send update to user */
		bcm_rx_update_and_send(op, lcf, rxdata);
		return;
	}

	/* do a real check in CAN frame data section */
	for (i = 0; i < rxdata->len; i += 8) {
		if ((get_u64(cf, i) & get_u64(rxdata, i)) !=
		    (get_u64(cf, i) & get_u64(lcf, i))) {
			bcm_rx_update_and_send(op, lcf, rxdata);
			return;
		}
	}

	if (op->flags & RX_CHECK_DLC) {
		/* do a real check in CAN frame length */
		if (rxdata->len != lcf->len) {
			bcm_rx_update_and_send(op, lcf, rxdata);
			return;
		}
	}
}


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/*
 * bcm_rx_starttimer - enable timeout monitoring for CAN frame reception
 */



static void bcm_rx_starttimer(struct bcm_op *op)
{
	if (op->flags & RX_NO_AUTOTIMER)
		return;

	if (op->kt_ival1)
		hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
}


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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);
}


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/*
 * bcm_rx_timeout_handler - when the (cyclic) CAN frame reception 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 * op->cfsiz);
	}

	return HRTIMER_NORESTART;
}


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Oliver Hartkopp75100.00%5100.00%


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/*
 * 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)
{
	struct canfd_frame *lcf = op->last_frames + op->cfsiz * index;

	if ((op->last_frames) && (lcf->flags & RX_THR)) {
		if (update)
			bcm_rx_changed(op, lcf);
		return 1;
	}
	return 0;
}


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/*
 * 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;
}


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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);
}


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Oliver Hartkopp30100.00%1100.00%


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/*
 * 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 = 0;
		return HRTIMER_NORESTART;
	}
}


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Total74100.00%3100.00%



/*
 * bcm_rx_handler - handle a CAN frame reception
 */



static void bcm_rx_handler(struct sk_buff *skb, void *data)
{
	struct bcm_op *op = (struct bcm_op *)data;
	const struct canfd_frame *rxframe = (struct canfd_frame *)skb->data;
	unsigned int i;

	if (op->can_id != rxframe->can_id)
		return;

	/* make sure to handle the correct frame type (CAN / CAN FD) */
	if (skb->len != op->cfsiz)
		return;

	/* disable timeout */
	hrtimer_cancel(&op->timer);

	/* 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, 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 - but only the
                 * first 64 bits of the frame data[] are relevant (CAN FD)
                 */

		for (i = 1; i < op->nframes; i++) {
			if ((get_u64(op->frames, 0) & get_u64(rxframe, 0)) ==
			    (get_u64(op->frames, 0) &
			     get_u64(op->frames + op->cfsiz * i, 0))) {
				bcm_rx_cmp_to_index(op, i, rxframe);
				break;
			}
		}
	}

rx_starttimer:
	bcm_rx_starttimer(op);
}


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/*
 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
 */



static struct bcm_op *bcm_find_op(struct list_head *ops,
				  struct bcm_msg_head *mh, int ifindex)
{
	struct bcm_op *op;

	list_for_each_entry(op, ops, list) {
		if ((op->can_id == mh->can_id) && (op->ifindex == ifindex) &&
		    (op->flags & CAN_FD_FRAME) == (mh->flags & CAN_FD_FRAME))
			return op;
	}

	return NULL;
}


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Oliver Hartkopp78100.00%3100.00%


Total78100.00%3100.00%






static void bcm_remove_op(struct bcm_op *op)
{
	if (op->tsklet.func) {
		while (test_bit(TASKLET_STATE_SCHED, &op->tsklet.state) ||
		       test_bit(TASKLET_STATE_RUN, &op->tsklet.state) ||
		       hrtimer_active(&op->timer)) {
			hrtimer_cancel(&op->timer);
			tasklet_kill(&op->tsklet);
		}
	}

	if (op->thrtsklet.func) {
		while (test_bit(TASKLET_STATE_SCHED, &op->thrtsklet.state) ||
		       test_bit(TASKLET_STATE_RUN, &op->thrtsklet.state) ||
		       hrtimer_active(&op->thrtimer)) {