diff options
Diffstat (limited to 'drivers/net/can/dev/netlink.c')
| -rw-r--r-- | drivers/net/can/dev/netlink.c | 627 |
1 files changed, 627 insertions, 0 deletions
diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c new file mode 100644 index 000000000..8efa22d9f --- /dev/null +++ b/drivers/net/can/dev/netlink.c @@ -0,0 +1,627 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix + * Copyright (C) 2006 Andrey Volkov, Varma Electronics + * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com> + * Copyright (C) 2021 Vincent Mailhol <mailhol.vincent@wanadoo.fr> + */ + +#include <linux/can/dev.h> +#include <net/rtnetlink.h> + +static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = { + [IFLA_CAN_STATE] = { .type = NLA_U32 }, + [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) }, + [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 }, + [IFLA_CAN_RESTART] = { .type = NLA_U32 }, + [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) }, + [IFLA_CAN_BITTIMING_CONST] = { .len = sizeof(struct can_bittiming_const) }, + [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) }, + [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) }, + [IFLA_CAN_DATA_BITTIMING] = { .len = sizeof(struct can_bittiming) }, + [IFLA_CAN_DATA_BITTIMING_CONST] = { .len = sizeof(struct can_bittiming_const) }, + [IFLA_CAN_TERMINATION] = { .type = NLA_U16 }, + [IFLA_CAN_TDC] = { .type = NLA_NESTED }, + [IFLA_CAN_CTRLMODE_EXT] = { .type = NLA_NESTED }, +}; + +static const struct nla_policy can_tdc_policy[IFLA_CAN_TDC_MAX + 1] = { + [IFLA_CAN_TDC_TDCV_MIN] = { .type = NLA_U32 }, + [IFLA_CAN_TDC_TDCV_MAX] = { .type = NLA_U32 }, + [IFLA_CAN_TDC_TDCO_MIN] = { .type = NLA_U32 }, + [IFLA_CAN_TDC_TDCO_MAX] = { .type = NLA_U32 }, + [IFLA_CAN_TDC_TDCF_MIN] = { .type = NLA_U32 }, + [IFLA_CAN_TDC_TDCF_MAX] = { .type = NLA_U32 }, + [IFLA_CAN_TDC_TDCV] = { .type = NLA_U32 }, + [IFLA_CAN_TDC_TDCO] = { .type = NLA_U32 }, + [IFLA_CAN_TDC_TDCF] = { .type = NLA_U32 }, +}; + +static int can_validate(struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + bool is_can_fd = false; + + /* Make sure that valid CAN FD configurations always consist of + * - nominal/arbitration bittiming + * - data bittiming + * - control mode with CAN_CTRLMODE_FD set + * - TDC parameters are coherent (details below) + */ + + if (!data) + return 0; + + if (data[IFLA_CAN_CTRLMODE]) { + struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]); + u32 tdc_flags = cm->flags & CAN_CTRLMODE_TDC_MASK; + + is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD; + + /* CAN_CTRLMODE_TDC_{AUTO,MANUAL} are mutually exclusive */ + if (tdc_flags == CAN_CTRLMODE_TDC_MASK) + return -EOPNOTSUPP; + /* If one of the CAN_CTRLMODE_TDC_* flag is set then + * TDC must be set and vice-versa + */ + if (!!tdc_flags != !!data[IFLA_CAN_TDC]) + return -EOPNOTSUPP; + /* If providing TDC parameters, at least TDCO is + * needed. TDCV is needed if and only if + * CAN_CTRLMODE_TDC_MANUAL is set + */ + if (data[IFLA_CAN_TDC]) { + struct nlattr *tb_tdc[IFLA_CAN_TDC_MAX + 1]; + int err; + + err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX, + data[IFLA_CAN_TDC], + can_tdc_policy, extack); + if (err) + return err; + + if (tb_tdc[IFLA_CAN_TDC_TDCV]) { + if (tdc_flags & CAN_CTRLMODE_TDC_AUTO) + return -EOPNOTSUPP; + } else { + if (tdc_flags & CAN_CTRLMODE_TDC_MANUAL) + return -EOPNOTSUPP; + } + + if (!tb_tdc[IFLA_CAN_TDC_TDCO]) + return -EOPNOTSUPP; + } + } + + if (is_can_fd) { + if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING]) + return -EOPNOTSUPP; + } + + if (data[IFLA_CAN_DATA_BITTIMING] || data[IFLA_CAN_TDC]) { + if (!is_can_fd) + return -EOPNOTSUPP; + } + + return 0; +} + +static int can_tdc_changelink(struct can_priv *priv, const struct nlattr *nla, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb_tdc[IFLA_CAN_TDC_MAX + 1]; + struct can_tdc tdc = { 0 }; + const struct can_tdc_const *tdc_const = priv->tdc_const; + int err; + + if (!tdc_const || !can_tdc_is_enabled(priv)) + return -EOPNOTSUPP; + + err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX, nla, + can_tdc_policy, extack); + if (err) + return err; + + if (tb_tdc[IFLA_CAN_TDC_TDCV]) { + u32 tdcv = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCV]); + + if (tdcv < tdc_const->tdcv_min || tdcv > tdc_const->tdcv_max) + return -EINVAL; + + tdc.tdcv = tdcv; + } + + if (tb_tdc[IFLA_CAN_TDC_TDCO]) { + u32 tdco = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCO]); + + if (tdco < tdc_const->tdco_min || tdco > tdc_const->tdco_max) + return -EINVAL; + + tdc.tdco = tdco; + } + + if (tb_tdc[IFLA_CAN_TDC_TDCF]) { + u32 tdcf = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCF]); + + if (tdcf < tdc_const->tdcf_min || tdcf > tdc_const->tdcf_max) + return -EINVAL; + + tdc.tdcf = tdcf; + } + + priv->tdc = tdc; + + return 0; +} + +static int can_changelink(struct net_device *dev, struct nlattr *tb[], + struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + struct can_priv *priv = netdev_priv(dev); + u32 tdc_mask = 0; + int err; + + /* We need synchronization with dev->stop() */ + ASSERT_RTNL(); + + if (data[IFLA_CAN_BITTIMING]) { + struct can_bittiming bt; + + /* Do not allow changing bittiming while running */ + if (dev->flags & IFF_UP) + return -EBUSY; + + /* Calculate bittiming parameters based on + * bittiming_const if set, otherwise pass bitrate + * directly via do_set_bitrate(). Bail out if neither + * is given. + */ + if (!priv->bittiming_const && !priv->do_set_bittiming && + !priv->bitrate_const) + return -EOPNOTSUPP; + + memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt)); + err = can_get_bittiming(dev, &bt, + priv->bittiming_const, + priv->bitrate_const, + priv->bitrate_const_cnt); + if (err) + return err; + + if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) { + netdev_err(dev, "arbitration bitrate surpasses transceiver capabilities of %d bps\n", + priv->bitrate_max); + return -EINVAL; + } + + memcpy(&priv->bittiming, &bt, sizeof(bt)); + + if (priv->do_set_bittiming) { + /* Finally, set the bit-timing registers */ + err = priv->do_set_bittiming(dev); + if (err) + return err; + } + } + + if (data[IFLA_CAN_CTRLMODE]) { + struct can_ctrlmode *cm; + u32 ctrlstatic; + u32 maskedflags; + + /* Do not allow changing controller mode while running */ + if (dev->flags & IFF_UP) + return -EBUSY; + cm = nla_data(data[IFLA_CAN_CTRLMODE]); + ctrlstatic = can_get_static_ctrlmode(priv); + maskedflags = cm->flags & cm->mask; + + /* check whether provided bits are allowed to be passed */ + if (maskedflags & ~(priv->ctrlmode_supported | ctrlstatic)) + return -EOPNOTSUPP; + + /* do not check for static fd-non-iso if 'fd' is disabled */ + if (!(maskedflags & CAN_CTRLMODE_FD)) + ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO; + + /* make sure static options are provided by configuration */ + if ((maskedflags & ctrlstatic) != ctrlstatic) + return -EOPNOTSUPP; + + /* clear bits to be modified and copy the flag values */ + priv->ctrlmode &= ~cm->mask; + priv->ctrlmode |= maskedflags; + + /* CAN_CTRLMODE_FD can only be set when driver supports FD */ + if (priv->ctrlmode & CAN_CTRLMODE_FD) { + dev->mtu = CANFD_MTU; + } else { + dev->mtu = CAN_MTU; + memset(&priv->data_bittiming, 0, + sizeof(priv->data_bittiming)); + priv->ctrlmode &= ~CAN_CTRLMODE_TDC_MASK; + memset(&priv->tdc, 0, sizeof(priv->tdc)); + } + + tdc_mask = cm->mask & CAN_CTRLMODE_TDC_MASK; + /* CAN_CTRLMODE_TDC_{AUTO,MANUAL} are mutually + * exclusive: make sure to turn the other one off + */ + if (tdc_mask) + priv->ctrlmode &= cm->flags | ~CAN_CTRLMODE_TDC_MASK; + } + + if (data[IFLA_CAN_RESTART_MS]) { + /* Do not allow changing restart delay while running */ + if (dev->flags & IFF_UP) + return -EBUSY; + priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]); + } + + if (data[IFLA_CAN_RESTART]) { + /* Do not allow a restart while not running */ + if (!(dev->flags & IFF_UP)) + return -EINVAL; + err = can_restart_now(dev); + if (err) + return err; + } + + if (data[IFLA_CAN_DATA_BITTIMING]) { + struct can_bittiming dbt; + + /* Do not allow changing bittiming while running */ + if (dev->flags & IFF_UP) + return -EBUSY; + + /* Calculate bittiming parameters based on + * data_bittiming_const if set, otherwise pass bitrate + * directly via do_set_bitrate(). Bail out if neither + * is given. + */ + if (!priv->data_bittiming_const && !priv->do_set_data_bittiming && + !priv->data_bitrate_const) + return -EOPNOTSUPP; + + memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]), + sizeof(dbt)); + err = can_get_bittiming(dev, &dbt, + priv->data_bittiming_const, + priv->data_bitrate_const, + priv->data_bitrate_const_cnt); + if (err) + return err; + + if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) { + netdev_err(dev, "canfd data bitrate surpasses transceiver capabilities of %d bps\n", + priv->bitrate_max); + return -EINVAL; + } + + memset(&priv->tdc, 0, sizeof(priv->tdc)); + if (data[IFLA_CAN_TDC]) { + /* TDC parameters are provided: use them */ + err = can_tdc_changelink(priv, data[IFLA_CAN_TDC], + extack); + if (err) { + priv->ctrlmode &= ~CAN_CTRLMODE_TDC_MASK; + return err; + } + } else if (!tdc_mask) { + /* Neither of TDC parameters nor TDC flags are + * provided: do calculation + */ + can_calc_tdco(&priv->tdc, priv->tdc_const, &priv->data_bittiming, + &priv->ctrlmode, priv->ctrlmode_supported); + } /* else: both CAN_CTRLMODE_TDC_{AUTO,MANUAL} are explicitly + * turned off. TDC is disabled: do nothing + */ + + memcpy(&priv->data_bittiming, &dbt, sizeof(dbt)); + + if (priv->do_set_data_bittiming) { + /* Finally, set the bit-timing registers */ + err = priv->do_set_data_bittiming(dev); + if (err) + return err; + } + } + + if (data[IFLA_CAN_TERMINATION]) { + const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]); + const unsigned int num_term = priv->termination_const_cnt; + unsigned int i; + + if (!priv->do_set_termination) + return -EOPNOTSUPP; + + /* check whether given value is supported by the interface */ + for (i = 0; i < num_term; i++) { + if (termval == priv->termination_const[i]) + break; + } + if (i >= num_term) + return -EINVAL; + + /* Finally, set the termination value */ + err = priv->do_set_termination(dev, termval); + if (err) + return err; + + priv->termination = termval; + } + + return 0; +} + +static size_t can_tdc_get_size(const struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + size_t size; + + if (!priv->tdc_const) + return 0; + + size = nla_total_size(0); /* nest IFLA_CAN_TDC */ + if (priv->ctrlmode_supported & CAN_CTRLMODE_TDC_MANUAL) { + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCV_MIN */ + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCV_MAX */ + } + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCO_MIN */ + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCO_MAX */ + if (priv->tdc_const->tdcf_max) { + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCF_MIN */ + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCF_MAX */ + } + + if (can_tdc_is_enabled(priv)) { + if (priv->ctrlmode & CAN_CTRLMODE_TDC_MANUAL || + priv->do_get_auto_tdcv) + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCV */ + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCO */ + if (priv->tdc_const->tdcf_max) + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCF */ + } + + return size; +} + +static size_t can_ctrlmode_ext_get_size(void) +{ + return nla_total_size(0) + /* nest IFLA_CAN_CTRLMODE_EXT */ + nla_total_size(sizeof(u32)); /* IFLA_CAN_CTRLMODE_SUPPORTED */ +} + +static size_t can_get_size(const struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + size_t size = 0; + + if (priv->bittiming.bitrate) /* IFLA_CAN_BITTIMING */ + size += nla_total_size(sizeof(struct can_bittiming)); + if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */ + size += nla_total_size(sizeof(struct can_bittiming_const)); + size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */ + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */ + size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */ + size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */ + if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */ + size += nla_total_size(sizeof(struct can_berr_counter)); + if (priv->data_bittiming.bitrate) /* IFLA_CAN_DATA_BITTIMING */ + size += nla_total_size(sizeof(struct can_bittiming)); + if (priv->data_bittiming_const) /* IFLA_CAN_DATA_BITTIMING_CONST */ + size += nla_total_size(sizeof(struct can_bittiming_const)); + if (priv->termination_const) { + size += nla_total_size(sizeof(priv->termination)); /* IFLA_CAN_TERMINATION */ + size += nla_total_size(sizeof(*priv->termination_const) * /* IFLA_CAN_TERMINATION_CONST */ + priv->termination_const_cnt); + } + if (priv->bitrate_const) /* IFLA_CAN_BITRATE_CONST */ + size += nla_total_size(sizeof(*priv->bitrate_const) * + priv->bitrate_const_cnt); + if (priv->data_bitrate_const) /* IFLA_CAN_DATA_BITRATE_CONST */ + size += nla_total_size(sizeof(*priv->data_bitrate_const) * + priv->data_bitrate_const_cnt); + size += sizeof(priv->bitrate_max); /* IFLA_CAN_BITRATE_MAX */ + size += can_tdc_get_size(dev); /* IFLA_CAN_TDC */ + size += can_ctrlmode_ext_get_size(); /* IFLA_CAN_CTRLMODE_EXT */ + + return size; +} + +static int can_tdc_fill_info(struct sk_buff *skb, const struct net_device *dev) +{ + struct nlattr *nest; + struct can_priv *priv = netdev_priv(dev); + struct can_tdc *tdc = &priv->tdc; + const struct can_tdc_const *tdc_const = priv->tdc_const; + + if (!tdc_const) + return 0; + + nest = nla_nest_start(skb, IFLA_CAN_TDC); + if (!nest) + return -EMSGSIZE; + + if (priv->ctrlmode_supported & CAN_CTRLMODE_TDC_MANUAL && + (nla_put_u32(skb, IFLA_CAN_TDC_TDCV_MIN, tdc_const->tdcv_min) || + nla_put_u32(skb, IFLA_CAN_TDC_TDCV_MAX, tdc_const->tdcv_max))) + goto err_cancel; + if (nla_put_u32(skb, IFLA_CAN_TDC_TDCO_MIN, tdc_const->tdco_min) || + nla_put_u32(skb, IFLA_CAN_TDC_TDCO_MAX, tdc_const->tdco_max)) + goto err_cancel; + if (tdc_const->tdcf_max && + (nla_put_u32(skb, IFLA_CAN_TDC_TDCF_MIN, tdc_const->tdcf_min) || + nla_put_u32(skb, IFLA_CAN_TDC_TDCF_MAX, tdc_const->tdcf_max))) + goto err_cancel; + + if (can_tdc_is_enabled(priv)) { + u32 tdcv; + int err = -EINVAL; + + if (priv->ctrlmode & CAN_CTRLMODE_TDC_MANUAL) { + tdcv = tdc->tdcv; + err = 0; + } else if (priv->do_get_auto_tdcv) { + err = priv->do_get_auto_tdcv(dev, &tdcv); + } + if (!err && nla_put_u32(skb, IFLA_CAN_TDC_TDCV, tdcv)) + goto err_cancel; + if (nla_put_u32(skb, IFLA_CAN_TDC_TDCO, tdc->tdco)) + goto err_cancel; + if (tdc_const->tdcf_max && + nla_put_u32(skb, IFLA_CAN_TDC_TDCF, tdc->tdcf)) + goto err_cancel; + } + + nla_nest_end(skb, nest); + return 0; + +err_cancel: + nla_nest_cancel(skb, nest); + return -EMSGSIZE; +} + +static int can_ctrlmode_ext_fill_info(struct sk_buff *skb, + const struct can_priv *priv) +{ + struct nlattr *nest; + + nest = nla_nest_start(skb, IFLA_CAN_CTRLMODE_EXT); + if (!nest) + return -EMSGSIZE; + + if (nla_put_u32(skb, IFLA_CAN_CTRLMODE_SUPPORTED, + priv->ctrlmode_supported)) { + nla_nest_cancel(skb, nest); + return -EMSGSIZE; + } + + nla_nest_end(skb, nest); + return 0; +} + +static int can_fill_info(struct sk_buff *skb, const struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + struct can_ctrlmode cm = {.flags = priv->ctrlmode}; + struct can_berr_counter bec = { }; + enum can_state state = priv->state; + + if (priv->do_get_state) + priv->do_get_state(dev, &state); + + if ((priv->bittiming.bitrate != CAN_BITRATE_UNSET && + priv->bittiming.bitrate != CAN_BITRATE_UNKNOWN && + nla_put(skb, IFLA_CAN_BITTIMING, + sizeof(priv->bittiming), &priv->bittiming)) || + + (priv->bittiming_const && + nla_put(skb, IFLA_CAN_BITTIMING_CONST, + sizeof(*priv->bittiming_const), priv->bittiming_const)) || + + nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) || + nla_put_u32(skb, IFLA_CAN_STATE, state) || + nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) || + nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) || + + (priv->do_get_berr_counter && + !priv->do_get_berr_counter(dev, &bec) && + nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) || + + (priv->data_bittiming.bitrate && + nla_put(skb, IFLA_CAN_DATA_BITTIMING, + sizeof(priv->data_bittiming), &priv->data_bittiming)) || + + (priv->data_bittiming_const && + nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST, + sizeof(*priv->data_bittiming_const), + priv->data_bittiming_const)) || + + (priv->termination_const && + (nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) || + nla_put(skb, IFLA_CAN_TERMINATION_CONST, + sizeof(*priv->termination_const) * + priv->termination_const_cnt, + priv->termination_const))) || + + (priv->bitrate_const && + nla_put(skb, IFLA_CAN_BITRATE_CONST, + sizeof(*priv->bitrate_const) * + priv->bitrate_const_cnt, + priv->bitrate_const)) || + + (priv->data_bitrate_const && + nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST, + sizeof(*priv->data_bitrate_const) * + priv->data_bitrate_const_cnt, + priv->data_bitrate_const)) || + + (nla_put(skb, IFLA_CAN_BITRATE_MAX, + sizeof(priv->bitrate_max), + &priv->bitrate_max)) || + + can_tdc_fill_info(skb, dev) || + + can_ctrlmode_ext_fill_info(skb, priv) + ) + + return -EMSGSIZE; + + return 0; +} + +static size_t can_get_xstats_size(const struct net_device *dev) +{ + return sizeof(struct can_device_stats); +} + +static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + + if (nla_put(skb, IFLA_INFO_XSTATS, + sizeof(priv->can_stats), &priv->can_stats)) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -EMSGSIZE; +} + +static int can_newlink(struct net *src_net, struct net_device *dev, + struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + return -EOPNOTSUPP; +} + +static void can_dellink(struct net_device *dev, struct list_head *head) +{ +} + +struct rtnl_link_ops can_link_ops __read_mostly = { + .kind = "can", + .netns_refund = true, + .maxtype = IFLA_CAN_MAX, + .policy = can_policy, + .setup = can_setup, + .validate = can_validate, + .newlink = can_newlink, + .changelink = can_changelink, + .dellink = can_dellink, + .get_size = can_get_size, + .fill_info = can_fill_info, + .get_xstats_size = can_get_xstats_size, + .fill_xstats = can_fill_xstats, +}; + +int can_netlink_register(void) +{ + return rtnl_link_register(&can_link_ops); +} + +void can_netlink_unregister(void) +{ + rtnl_link_unregister(&can_link_ops); +} |