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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/net/can/dev | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/can/dev')
-rw-r--r-- | drivers/net/can/dev/Makefile | 12 | ||||
-rw-r--r-- | drivers/net/can/dev/bittiming.c | 87 | ||||
-rw-r--r-- | drivers/net/can/dev/calc_bittiming.c | 202 | ||||
-rw-r--r-- | drivers/net/can/dev/dev.c | 573 | ||||
-rw-r--r-- | drivers/net/can/dev/length.c | 95 | ||||
-rw-r--r-- | drivers/net/can/dev/netlink.c | 627 | ||||
-rw-r--r-- | drivers/net/can/dev/rx-offload.c | 401 | ||||
-rw-r--r-- | drivers/net/can/dev/skb.c | 374 |
8 files changed, 2371 insertions, 0 deletions
diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile new file mode 100644 index 000000000..633687d6b --- /dev/null +++ b/drivers/net/can/dev/Makefile @@ -0,0 +1,12 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_CAN_DEV) += can-dev.o + +can-dev-y += skb.o + +can-dev-$(CONFIG_CAN_CALC_BITTIMING) += calc_bittiming.o +can-dev-$(CONFIG_CAN_NETLINK) += bittiming.o +can-dev-$(CONFIG_CAN_NETLINK) += dev.o +can-dev-$(CONFIG_CAN_NETLINK) += length.o +can-dev-$(CONFIG_CAN_NETLINK) += netlink.o +can-dev-$(CONFIG_CAN_RX_OFFLOAD) += rx-offload.o diff --git a/drivers/net/can/dev/bittiming.c b/drivers/net/can/dev/bittiming.c new file mode 100644 index 000000000..7ae80763c --- /dev/null +++ b/drivers/net/can/dev/bittiming.c @@ -0,0 +1,87 @@ +// 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> + */ + +#include <linux/can/dev.h> + +/* Checks the validity of the specified bit-timing parameters prop_seg, + * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate + * prescaler value brp. You can find more information in the header + * file linux/can/netlink.h. + */ +static int can_fixup_bittiming(const struct net_device *dev, struct can_bittiming *bt, + const struct can_bittiming_const *btc) +{ + const struct can_priv *priv = netdev_priv(dev); + unsigned int tseg1, alltseg; + u64 brp64; + + tseg1 = bt->prop_seg + bt->phase_seg1; + if (!bt->sjw) + bt->sjw = 1; + if (bt->sjw > btc->sjw_max || + tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max || + bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max) + return -ERANGE; + + brp64 = (u64)priv->clock.freq * (u64)bt->tq; + if (btc->brp_inc > 1) + do_div(brp64, btc->brp_inc); + brp64 += 500000000UL - 1; + do_div(brp64, 1000000000UL); /* the practicable BRP */ + if (btc->brp_inc > 1) + brp64 *= btc->brp_inc; + bt->brp = (u32)brp64; + + if (bt->brp < btc->brp_min || bt->brp > btc->brp_max) + return -EINVAL; + + alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1; + bt->bitrate = priv->clock.freq / (bt->brp * alltseg); + bt->sample_point = ((tseg1 + 1) * 1000) / alltseg; + + return 0; +} + +/* Checks the validity of predefined bitrate settings */ +static int +can_validate_bitrate(const struct net_device *dev, const struct can_bittiming *bt, + const u32 *bitrate_const, + const unsigned int bitrate_const_cnt) +{ + unsigned int i; + + for (i = 0; i < bitrate_const_cnt; i++) { + if (bt->bitrate == bitrate_const[i]) + return 0; + } + + return -EINVAL; +} + +int can_get_bittiming(const struct net_device *dev, struct can_bittiming *bt, + const struct can_bittiming_const *btc, + const u32 *bitrate_const, + const unsigned int bitrate_const_cnt) +{ + int err; + + /* Depending on the given can_bittiming parameter structure the CAN + * timing parameters are calculated based on the provided bitrate OR + * alternatively the CAN timing parameters (tq, prop_seg, etc.) are + * provided directly which are then checked and fixed up. + */ + if (!bt->tq && bt->bitrate && btc) + err = can_calc_bittiming(dev, bt, btc); + else if (bt->tq && !bt->bitrate && btc) + err = can_fixup_bittiming(dev, bt, btc); + else if (!bt->tq && bt->bitrate && bitrate_const) + err = can_validate_bitrate(dev, bt, bitrate_const, + bitrate_const_cnt); + else + err = -EINVAL; + + return err; +} diff --git a/drivers/net/can/dev/calc_bittiming.c b/drivers/net/can/dev/calc_bittiming.c new file mode 100644 index 000000000..d3caa0406 --- /dev/null +++ b/drivers/net/can/dev/calc_bittiming.c @@ -0,0 +1,202 @@ +// 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> + */ + +#include <linux/units.h> +#include <linux/can/dev.h> + +#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */ + +/* Bit-timing calculation derived from: + * + * Code based on LinCAN sources and H8S2638 project + * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz + * Copyright 2005 Stanislav Marek + * email: pisa@cmp.felk.cvut.cz + * + * Calculates proper bit-timing parameters for a specified bit-rate + * and sample-point, which can then be used to set the bit-timing + * registers of the CAN controller. You can find more information + * in the header file linux/can/netlink.h. + */ +static int +can_update_sample_point(const struct can_bittiming_const *btc, + const unsigned int sample_point_nominal, const unsigned int tseg, + unsigned int *tseg1_ptr, unsigned int *tseg2_ptr, + unsigned int *sample_point_error_ptr) +{ + unsigned int sample_point_error, best_sample_point_error = UINT_MAX; + unsigned int sample_point, best_sample_point = 0; + unsigned int tseg1, tseg2; + int i; + + for (i = 0; i <= 1; i++) { + tseg2 = tseg + CAN_SYNC_SEG - + (sample_point_nominal * (tseg + CAN_SYNC_SEG)) / + 1000 - i; + tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max); + tseg1 = tseg - tseg2; + if (tseg1 > btc->tseg1_max) { + tseg1 = btc->tseg1_max; + tseg2 = tseg - tseg1; + } + + sample_point = 1000 * (tseg + CAN_SYNC_SEG - tseg2) / + (tseg + CAN_SYNC_SEG); + sample_point_error = abs(sample_point_nominal - sample_point); + + if (sample_point <= sample_point_nominal && + sample_point_error < best_sample_point_error) { + best_sample_point = sample_point; + best_sample_point_error = sample_point_error; + *tseg1_ptr = tseg1; + *tseg2_ptr = tseg2; + } + } + + if (sample_point_error_ptr) + *sample_point_error_ptr = best_sample_point_error; + + return best_sample_point; +} + +int can_calc_bittiming(const struct net_device *dev, struct can_bittiming *bt, + const struct can_bittiming_const *btc) +{ + struct can_priv *priv = netdev_priv(dev); + unsigned int bitrate; /* current bitrate */ + unsigned int bitrate_error; /* difference between current and nominal value */ + unsigned int best_bitrate_error = UINT_MAX; + unsigned int sample_point_error; /* difference between current and nominal value */ + unsigned int best_sample_point_error = UINT_MAX; + unsigned int sample_point_nominal; /* nominal sample point */ + unsigned int best_tseg = 0; /* current best value for tseg */ + unsigned int best_brp = 0; /* current best value for brp */ + unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0; + u64 v64; + + /* Use CiA recommended sample points */ + if (bt->sample_point) { + sample_point_nominal = bt->sample_point; + } else { + if (bt->bitrate > 800 * KILO /* BPS */) + sample_point_nominal = 750; + else if (bt->bitrate > 500 * KILO /* BPS */) + sample_point_nominal = 800; + else + sample_point_nominal = 875; + } + + /* tseg even = round down, odd = round up */ + for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1; + tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) { + tsegall = CAN_SYNC_SEG + tseg / 2; + + /* Compute all possible tseg choices (tseg=tseg1+tseg2) */ + brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2; + + /* choose brp step which is possible in system */ + brp = (brp / btc->brp_inc) * btc->brp_inc; + if (brp < btc->brp_min || brp > btc->brp_max) + continue; + + bitrate = priv->clock.freq / (brp * tsegall); + bitrate_error = abs(bt->bitrate - bitrate); + + /* tseg brp biterror */ + if (bitrate_error > best_bitrate_error) + continue; + + /* reset sample point error if we have a better bitrate */ + if (bitrate_error < best_bitrate_error) + best_sample_point_error = UINT_MAX; + + can_update_sample_point(btc, sample_point_nominal, tseg / 2, + &tseg1, &tseg2, &sample_point_error); + if (sample_point_error >= best_sample_point_error) + continue; + + best_sample_point_error = sample_point_error; + best_bitrate_error = bitrate_error; + best_tseg = tseg / 2; + best_brp = brp; + + if (bitrate_error == 0 && sample_point_error == 0) + break; + } + + if (best_bitrate_error) { + /* Error in one-tenth of a percent */ + v64 = (u64)best_bitrate_error * 1000; + do_div(v64, bt->bitrate); + bitrate_error = (u32)v64; + if (bitrate_error > CAN_CALC_MAX_ERROR) { + netdev_err(dev, + "bitrate error %d.%d%% too high\n", + bitrate_error / 10, bitrate_error % 10); + return -EDOM; + } + netdev_warn(dev, "bitrate error %d.%d%%\n", + bitrate_error / 10, bitrate_error % 10); + } + + /* real sample point */ + bt->sample_point = can_update_sample_point(btc, sample_point_nominal, + best_tseg, &tseg1, &tseg2, + NULL); + + v64 = (u64)best_brp * 1000 * 1000 * 1000; + do_div(v64, priv->clock.freq); + bt->tq = (u32)v64; + bt->prop_seg = tseg1 / 2; + bt->phase_seg1 = tseg1 - bt->prop_seg; + bt->phase_seg2 = tseg2; + + /* check for sjw user settings */ + if (!bt->sjw || !btc->sjw_max) { + bt->sjw = 1; + } else { + /* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */ + if (bt->sjw > btc->sjw_max) + bt->sjw = btc->sjw_max; + /* bt->sjw must not be higher than tseg2 */ + if (tseg2 < bt->sjw) + bt->sjw = tseg2; + } + + bt->brp = best_brp; + + /* real bitrate */ + bt->bitrate = priv->clock.freq / + (bt->brp * (CAN_SYNC_SEG + tseg1 + tseg2)); + + return 0; +} + +void can_calc_tdco(struct can_tdc *tdc, const struct can_tdc_const *tdc_const, + const struct can_bittiming *dbt, + u32 *ctrlmode, u32 ctrlmode_supported) + +{ + if (!tdc_const || !(ctrlmode_supported & CAN_CTRLMODE_TDC_AUTO)) + return; + + *ctrlmode &= ~CAN_CTRLMODE_TDC_MASK; + + /* As specified in ISO 11898-1 section 11.3.3 "Transmitter + * delay compensation" (TDC) is only applicable if data BRP is + * one or two. + */ + if (dbt->brp == 1 || dbt->brp == 2) { + /* Sample point in clock periods */ + u32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg + + dbt->phase_seg1) * dbt->brp; + + if (sample_point_in_tc < tdc_const->tdco_min) + return; + tdc->tdco = min(sample_point_in_tc, tdc_const->tdco_max); + *ctrlmode |= CAN_CTRLMODE_TDC_AUTO; + } +} diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c new file mode 100644 index 000000000..f685479ed --- /dev/null +++ b/drivers/net/can/dev/dev.c @@ -0,0 +1,573 @@ +// 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> + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/netdevice.h> +#include <linux/if_arp.h> +#include <linux/workqueue.h> +#include <linux/can.h> +#include <linux/can/can-ml.h> +#include <linux/can/dev.h> +#include <linux/can/skb.h> +#include <linux/gpio/consumer.h> +#include <linux/of.h> + +static void can_update_state_error_stats(struct net_device *dev, + enum can_state new_state) +{ + struct can_priv *priv = netdev_priv(dev); + + if (new_state <= priv->state) + return; + + switch (new_state) { + case CAN_STATE_ERROR_WARNING: + priv->can_stats.error_warning++; + break; + case CAN_STATE_ERROR_PASSIVE: + priv->can_stats.error_passive++; + break; + case CAN_STATE_BUS_OFF: + priv->can_stats.bus_off++; + break; + default: + break; + } +} + +static int can_tx_state_to_frame(struct net_device *dev, enum can_state state) +{ + switch (state) { + case CAN_STATE_ERROR_ACTIVE: + return CAN_ERR_CRTL_ACTIVE; + case CAN_STATE_ERROR_WARNING: + return CAN_ERR_CRTL_TX_WARNING; + case CAN_STATE_ERROR_PASSIVE: + return CAN_ERR_CRTL_TX_PASSIVE; + default: + return 0; + } +} + +static int can_rx_state_to_frame(struct net_device *dev, enum can_state state) +{ + switch (state) { + case CAN_STATE_ERROR_ACTIVE: + return CAN_ERR_CRTL_ACTIVE; + case CAN_STATE_ERROR_WARNING: + return CAN_ERR_CRTL_RX_WARNING; + case CAN_STATE_ERROR_PASSIVE: + return CAN_ERR_CRTL_RX_PASSIVE; + default: + return 0; + } +} + +const char *can_get_state_str(const enum can_state state) +{ + switch (state) { + case CAN_STATE_ERROR_ACTIVE: + return "Error Active"; + case CAN_STATE_ERROR_WARNING: + return "Error Warning"; + case CAN_STATE_ERROR_PASSIVE: + return "Error Passive"; + case CAN_STATE_BUS_OFF: + return "Bus Off"; + case CAN_STATE_STOPPED: + return "Stopped"; + case CAN_STATE_SLEEPING: + return "Sleeping"; + default: + return "<unknown>"; + } + + return "<unknown>"; +} +EXPORT_SYMBOL_GPL(can_get_state_str); + +void can_change_state(struct net_device *dev, struct can_frame *cf, + enum can_state tx_state, enum can_state rx_state) +{ + struct can_priv *priv = netdev_priv(dev); + enum can_state new_state = max(tx_state, rx_state); + + if (unlikely(new_state == priv->state)) { + netdev_warn(dev, "%s: oops, state did not change", __func__); + return; + } + + netdev_dbg(dev, "Controller changed from %s State (%d) into %s State (%d).\n", + can_get_state_str(priv->state), priv->state, + can_get_state_str(new_state), new_state); + + can_update_state_error_stats(dev, new_state); + priv->state = new_state; + + if (!cf) + return; + + if (unlikely(new_state == CAN_STATE_BUS_OFF)) { + cf->can_id |= CAN_ERR_BUSOFF; + return; + } + + cf->can_id |= CAN_ERR_CRTL; + cf->data[1] |= tx_state >= rx_state ? + can_tx_state_to_frame(dev, tx_state) : 0; + cf->data[1] |= tx_state <= rx_state ? + can_rx_state_to_frame(dev, rx_state) : 0; +} +EXPORT_SYMBOL_GPL(can_change_state); + +/* CAN device restart for bus-off recovery */ +static void can_restart(struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + struct sk_buff *skb; + struct can_frame *cf; + int err; + + if (netif_carrier_ok(dev)) + netdev_err(dev, "Attempt to restart for bus-off recovery, but carrier is OK?\n"); + + /* No synchronization needed because the device is bus-off and + * no messages can come in or go out. + */ + can_flush_echo_skb(dev); + + /* send restart message upstream */ + skb = alloc_can_err_skb(dev, &cf); + if (!skb) + goto restart; + + cf->can_id |= CAN_ERR_RESTARTED; + + netif_rx(skb); + +restart: + netdev_dbg(dev, "restarted\n"); + priv->can_stats.restarts++; + + /* Now restart the device */ + netif_carrier_on(dev); + err = priv->do_set_mode(dev, CAN_MODE_START); + if (err) { + netdev_err(dev, "Error %d during restart", err); + netif_carrier_off(dev); + } +} + +static void can_restart_work(struct work_struct *work) +{ + struct delayed_work *dwork = to_delayed_work(work); + struct can_priv *priv = container_of(dwork, struct can_priv, + restart_work); + + can_restart(priv->dev); +} + +int can_restart_now(struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + + /* A manual restart is only permitted if automatic restart is + * disabled and the device is in the bus-off state + */ + if (priv->restart_ms) + return -EINVAL; + if (priv->state != CAN_STATE_BUS_OFF) + return -EBUSY; + + cancel_delayed_work_sync(&priv->restart_work); + can_restart(dev); + + return 0; +} + +/* CAN bus-off + * + * This functions should be called when the device goes bus-off to + * tell the netif layer that no more packets can be sent or received. + * If enabled, a timer is started to trigger bus-off recovery. + */ +void can_bus_off(struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + + if (priv->restart_ms) + netdev_info(dev, "bus-off, scheduling restart in %d ms\n", + priv->restart_ms); + else + netdev_info(dev, "bus-off\n"); + + netif_carrier_off(dev); + + if (priv->restart_ms) + schedule_delayed_work(&priv->restart_work, + msecs_to_jiffies(priv->restart_ms)); +} +EXPORT_SYMBOL_GPL(can_bus_off); + +void can_setup(struct net_device *dev) +{ + dev->type = ARPHRD_CAN; + dev->mtu = CAN_MTU; + dev->hard_header_len = 0; + dev->addr_len = 0; + dev->tx_queue_len = 10; + + /* New-style flags. */ + dev->flags = IFF_NOARP; + dev->features = NETIF_F_HW_CSUM; +} + +/* Allocate and setup space for the CAN network device */ +struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, + unsigned int txqs, unsigned int rxqs) +{ + struct can_ml_priv *can_ml; + struct net_device *dev; + struct can_priv *priv; + int size; + + /* We put the driver's priv, the CAN mid layer priv and the + * echo skb into the netdevice's priv. The memory layout for + * the netdev_priv is like this: + * + * +-------------------------+ + * | driver's priv | + * +-------------------------+ + * | struct can_ml_priv | + * +-------------------------+ + * | array of struct sk_buff | + * +-------------------------+ + */ + + size = ALIGN(sizeof_priv, NETDEV_ALIGN) + sizeof(struct can_ml_priv); + + if (echo_skb_max) + size = ALIGN(size, sizeof(struct sk_buff *)) + + echo_skb_max * sizeof(struct sk_buff *); + + dev = alloc_netdev_mqs(size, "can%d", NET_NAME_UNKNOWN, can_setup, + txqs, rxqs); + if (!dev) + return NULL; + + priv = netdev_priv(dev); + priv->dev = dev; + + can_ml = (void *)priv + ALIGN(sizeof_priv, NETDEV_ALIGN); + can_set_ml_priv(dev, can_ml); + + if (echo_skb_max) { + priv->echo_skb_max = echo_skb_max; + priv->echo_skb = (void *)priv + + (size - echo_skb_max * sizeof(struct sk_buff *)); + } + + priv->state = CAN_STATE_STOPPED; + + INIT_DELAYED_WORK(&priv->restart_work, can_restart_work); + + return dev; +} +EXPORT_SYMBOL_GPL(alloc_candev_mqs); + +/* Free space of the CAN network device */ +void free_candev(struct net_device *dev) +{ + free_netdev(dev); +} +EXPORT_SYMBOL_GPL(free_candev); + +/* changing MTU and control mode for CAN/CANFD devices */ +int can_change_mtu(struct net_device *dev, int new_mtu) +{ + struct can_priv *priv = netdev_priv(dev); + u32 ctrlmode_static = can_get_static_ctrlmode(priv); + + /* Do not allow changing the MTU while running */ + if (dev->flags & IFF_UP) + return -EBUSY; + + /* allow change of MTU according to the CANFD ability of the device */ + switch (new_mtu) { + case CAN_MTU: + /* 'CANFD-only' controllers can not switch to CAN_MTU */ + if (ctrlmode_static & CAN_CTRLMODE_FD) + return -EINVAL; + + priv->ctrlmode &= ~CAN_CTRLMODE_FD; + break; + + case CANFD_MTU: + /* check for potential CANFD ability */ + if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD) && + !(ctrlmode_static & CAN_CTRLMODE_FD)) + return -EINVAL; + + priv->ctrlmode |= CAN_CTRLMODE_FD; + break; + + default: + return -EINVAL; + } + + dev->mtu = new_mtu; + return 0; +} +EXPORT_SYMBOL_GPL(can_change_mtu); + +/* generic implementation of netdev_ops::ndo_eth_ioctl for CAN devices + * supporting hardware timestamps + */ +int can_eth_ioctl_hwts(struct net_device *netdev, struct ifreq *ifr, int cmd) +{ + struct hwtstamp_config hwts_cfg = { 0 }; + + switch (cmd) { + case SIOCSHWTSTAMP: /* set */ + if (copy_from_user(&hwts_cfg, ifr->ifr_data, sizeof(hwts_cfg))) + return -EFAULT; + if (hwts_cfg.tx_type == HWTSTAMP_TX_ON && + hwts_cfg.rx_filter == HWTSTAMP_FILTER_ALL) + return 0; + return -ERANGE; + + case SIOCGHWTSTAMP: /* get */ + hwts_cfg.tx_type = HWTSTAMP_TX_ON; + hwts_cfg.rx_filter = HWTSTAMP_FILTER_ALL; + if (copy_to_user(ifr->ifr_data, &hwts_cfg, sizeof(hwts_cfg))) + return -EFAULT; + return 0; + + default: + return -EOPNOTSUPP; + } +} +EXPORT_SYMBOL(can_eth_ioctl_hwts); + +/* generic implementation of ethtool_ops::get_ts_info for CAN devices + * supporting hardware timestamps + */ +int can_ethtool_op_get_ts_info_hwts(struct net_device *dev, + struct ethtool_ts_info *info) +{ + info->so_timestamping = + SOF_TIMESTAMPING_TX_SOFTWARE | + SOF_TIMESTAMPING_RX_SOFTWARE | + SOF_TIMESTAMPING_SOFTWARE | + SOF_TIMESTAMPING_TX_HARDWARE | + SOF_TIMESTAMPING_RX_HARDWARE | + SOF_TIMESTAMPING_RAW_HARDWARE; + info->phc_index = -1; + info->tx_types = BIT(HWTSTAMP_TX_ON); + info->rx_filters = BIT(HWTSTAMP_FILTER_ALL); + + return 0; +} +EXPORT_SYMBOL(can_ethtool_op_get_ts_info_hwts); + +/* Common open function when the device gets opened. + * + * This function should be called in the open function of the device + * driver. + */ +int open_candev(struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + + if (!priv->bittiming.bitrate) { + netdev_err(dev, "bit-timing not yet defined\n"); + return -EINVAL; + } + + /* For CAN FD the data bitrate has to be >= the arbitration bitrate */ + if ((priv->ctrlmode & CAN_CTRLMODE_FD) && + (!priv->data_bittiming.bitrate || + priv->data_bittiming.bitrate < priv->bittiming.bitrate)) { + netdev_err(dev, "incorrect/missing data bit-timing\n"); + return -EINVAL; + } + + /* Switch carrier on if device was stopped while in bus-off state */ + if (!netif_carrier_ok(dev)) + netif_carrier_on(dev); + + return 0; +} +EXPORT_SYMBOL_GPL(open_candev); + +#ifdef CONFIG_OF +/* Common function that can be used to understand the limitation of + * a transceiver when it provides no means to determine these limitations + * at runtime. + */ +void of_can_transceiver(struct net_device *dev) +{ + struct device_node *dn; + struct can_priv *priv = netdev_priv(dev); + struct device_node *np = dev->dev.parent->of_node; + int ret; + + dn = of_get_child_by_name(np, "can-transceiver"); + if (!dn) + return; + + ret = of_property_read_u32(dn, "max-bitrate", &priv->bitrate_max); + of_node_put(dn); + if ((ret && ret != -EINVAL) || (!ret && !priv->bitrate_max)) + netdev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit.\n"); +} +EXPORT_SYMBOL_GPL(of_can_transceiver); +#endif + +/* Common close function for cleanup before the device gets closed. + * + * This function should be called in the close function of the device + * driver. + */ +void close_candev(struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + + cancel_delayed_work_sync(&priv->restart_work); + can_flush_echo_skb(dev); +} +EXPORT_SYMBOL_GPL(close_candev); + +static int can_set_termination(struct net_device *ndev, u16 term) +{ + struct can_priv *priv = netdev_priv(ndev); + int set; + + if (term == priv->termination_gpio_ohms[CAN_TERMINATION_GPIO_ENABLED]) + set = 1; + else + set = 0; + + gpiod_set_value(priv->termination_gpio, set); + + return 0; +} + +static int can_get_termination(struct net_device *ndev) +{ + struct can_priv *priv = netdev_priv(ndev); + struct device *dev = ndev->dev.parent; + struct gpio_desc *gpio; + u32 term; + int ret; + + /* Disabling termination by default is the safe choice: Else if many + * bus participants enable it, no communication is possible at all. + */ + gpio = devm_gpiod_get_optional(dev, "termination", GPIOD_OUT_LOW); + if (IS_ERR(gpio)) + return dev_err_probe(dev, PTR_ERR(gpio), + "Cannot get termination-gpios\n"); + + if (!gpio) + return 0; + + ret = device_property_read_u32(dev, "termination-ohms", &term); + if (ret) { + netdev_err(ndev, "Cannot get termination-ohms: %pe\n", + ERR_PTR(ret)); + return ret; + } + + if (term > U16_MAX) { + netdev_err(ndev, "Invalid termination-ohms value (%u > %u)\n", + term, U16_MAX); + return -EINVAL; + } + + priv->termination_const_cnt = ARRAY_SIZE(priv->termination_gpio_ohms); + priv->termination_const = priv->termination_gpio_ohms; + priv->termination_gpio = gpio; + priv->termination_gpio_ohms[CAN_TERMINATION_GPIO_DISABLED] = + CAN_TERMINATION_DISABLED; + priv->termination_gpio_ohms[CAN_TERMINATION_GPIO_ENABLED] = term; + priv->do_set_termination = can_set_termination; + + return 0; +} + +/* Register the CAN network device */ +int register_candev(struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + int err; + + /* Ensure termination_const, termination_const_cnt and + * do_set_termination consistency. All must be either set or + * unset. + */ + if ((!priv->termination_const != !priv->termination_const_cnt) || + (!priv->termination_const != !priv->do_set_termination)) + return -EINVAL; + + if (!priv->bitrate_const != !priv->bitrate_const_cnt) + return -EINVAL; + + if (!priv->data_bitrate_const != !priv->data_bitrate_const_cnt) + return -EINVAL; + + if (!priv->termination_const) { + err = can_get_termination(dev); + if (err) + return err; + } + + dev->rtnl_link_ops = &can_link_ops; + netif_carrier_off(dev); + + return register_netdev(dev); +} +EXPORT_SYMBOL_GPL(register_candev); + +/* Unregister the CAN network device */ +void unregister_candev(struct net_device *dev) +{ + unregister_netdev(dev); +} +EXPORT_SYMBOL_GPL(unregister_candev); + +/* Test if a network device is a candev based device + * and return the can_priv* if so. + */ +struct can_priv *safe_candev_priv(struct net_device *dev) +{ + if (dev->type != ARPHRD_CAN || dev->rtnl_link_ops != &can_link_ops) + return NULL; + + return netdev_priv(dev); +} +EXPORT_SYMBOL_GPL(safe_candev_priv); + +static __init int can_dev_init(void) +{ + int err; + + err = can_netlink_register(); + if (!err) + pr_info("CAN device driver interface\n"); + + return err; +} +module_init(can_dev_init); + +static __exit void can_dev_exit(void) +{ + can_netlink_unregister(); +} +module_exit(can_dev_exit); + +MODULE_ALIAS_RTNL_LINK("can"); diff --git a/drivers/net/can/dev/length.c b/drivers/net/can/dev/length.c new file mode 100644 index 000000000..b48140b11 --- /dev/null +++ b/drivers/net/can/dev/length.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (C) 2012, 2020 Oliver Hartkopp <socketcan@hartkopp.net> + */ + +#include <linux/can/dev.h> + +/* CAN DLC to real data length conversion helpers */ + +static const u8 dlc2len[] = { + 0, 1, 2, 3, 4, 5, 6, 7, + 8, 12, 16, 20, 24, 32, 48, 64 +}; + +/* get data length from raw data length code (DLC) */ +u8 can_fd_dlc2len(u8 dlc) +{ + return dlc2len[dlc & 0x0F]; +} +EXPORT_SYMBOL_GPL(can_fd_dlc2len); + +static const u8 len2dlc[] = { + 0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */ + 9, 9, 9, 9, /* 9 - 12 */ + 10, 10, 10, 10, /* 13 - 16 */ + 11, 11, 11, 11, /* 17 - 20 */ + 12, 12, 12, 12, /* 21 - 24 */ + 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */ + 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */ + 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */ + 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */ + 15, 15, 15, 15, 15, 15, 15, 15 /* 57 - 64 */ +}; + +/* map the sanitized data length to an appropriate data length code */ +u8 can_fd_len2dlc(u8 len) +{ + /* check for length mapping table size at build time */ + BUILD_BUG_ON(ARRAY_SIZE(len2dlc) != CANFD_MAX_DLEN + 1); + + if (unlikely(len > CANFD_MAX_DLEN)) + return CANFD_MAX_DLC; + + return len2dlc[len]; +} +EXPORT_SYMBOL_GPL(can_fd_len2dlc); + +/** + * can_skb_get_frame_len() - Calculate the CAN Frame length in bytes + * of a given skb. + * @skb: socket buffer of a CAN message. + * + * Do a rough calculation: bit stuffing is ignored and length in bits + * is rounded up to a length in bytes. + * + * Rationale: this function is to be used for the BQL functions + * (netdev_sent_queue() and netdev_completed_queue()) which expect a + * value in bytes. Just using skb->len is insufficient because it will + * return the constant value of CAN(FD)_MTU. Doing the bit stuffing + * calculation would be too expensive in term of computing resources + * for no noticeable gain. + * + * Remarks: The payload of CAN FD frames with BRS flag are sent at a + * different bitrate. Currently, the can-utils canbusload tool does + * not support CAN-FD yet and so we could not run any benchmark to + * measure the impact. There might be possible improvement here. + * + * Return: length in bytes. + */ +unsigned int can_skb_get_frame_len(const struct sk_buff *skb) +{ + const struct canfd_frame *cf = (const struct canfd_frame *)skb->data; + u8 len; + + if (can_is_canfd_skb(skb)) + len = canfd_sanitize_len(cf->len); + else if (cf->can_id & CAN_RTR_FLAG) + len = 0; + else + len = cf->len; + + if (can_is_canfd_skb(skb)) { + if (cf->can_id & CAN_EFF_FLAG) + len += CANFD_FRAME_OVERHEAD_EFF; + else + len += CANFD_FRAME_OVERHEAD_SFF; + } else { + if (cf->can_id & CAN_EFF_FLAG) + len += CAN_FRAME_OVERHEAD_EFF; + else + len += CAN_FRAME_OVERHEAD_SFF; + } + + return len; +} +EXPORT_SYMBOL_GPL(can_skb_get_frame_len); 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); +} diff --git a/drivers/net/can/dev/rx-offload.c b/drivers/net/can/dev/rx-offload.c new file mode 100644 index 000000000..81ebf0562 --- /dev/null +++ b/drivers/net/can/dev/rx-offload.c @@ -0,0 +1,401 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2014 Protonic Holland, + * David Jander + * Copyright (C) 2014-2021 Pengutronix, + * Marc Kleine-Budde <kernel@pengutronix.de> + */ + +#include <linux/can/dev.h> +#include <linux/can/rx-offload.h> + +struct can_rx_offload_cb { + u32 timestamp; +}; + +static inline struct can_rx_offload_cb * +can_rx_offload_get_cb(struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(struct can_rx_offload_cb) > sizeof(skb->cb)); + + return (struct can_rx_offload_cb *)skb->cb; +} + +static inline bool +can_rx_offload_le(struct can_rx_offload *offload, + unsigned int a, unsigned int b) +{ + if (offload->inc) + return a <= b; + else + return a >= b; +} + +static inline unsigned int +can_rx_offload_inc(struct can_rx_offload *offload, unsigned int *val) +{ + if (offload->inc) + return (*val)++; + else + return (*val)--; +} + +static int can_rx_offload_napi_poll(struct napi_struct *napi, int quota) +{ + struct can_rx_offload *offload = container_of(napi, + struct can_rx_offload, + napi); + struct net_device *dev = offload->dev; + struct net_device_stats *stats = &dev->stats; + struct sk_buff *skb; + int work_done = 0; + + while ((work_done < quota) && + (skb = skb_dequeue(&offload->skb_queue))) { + struct can_frame *cf = (struct can_frame *)skb->data; + + work_done++; + if (!(cf->can_id & CAN_ERR_FLAG)) { + stats->rx_packets++; + if (!(cf->can_id & CAN_RTR_FLAG)) + stats->rx_bytes += cf->len; + } + netif_receive_skb(skb); + } + + if (work_done < quota) { + napi_complete_done(napi, work_done); + + /* Check if there was another interrupt */ + if (!skb_queue_empty(&offload->skb_queue)) + napi_reschedule(&offload->napi); + } + + return work_done; +} + +static inline void +__skb_queue_add_sort(struct sk_buff_head *head, struct sk_buff *new, + int (*compare)(struct sk_buff *a, struct sk_buff *b)) +{ + struct sk_buff *pos, *insert = NULL; + + skb_queue_reverse_walk(head, pos) { + const struct can_rx_offload_cb *cb_pos, *cb_new; + + cb_pos = can_rx_offload_get_cb(pos); + cb_new = can_rx_offload_get_cb(new); + + netdev_dbg(new->dev, + "%s: pos=0x%08x, new=0x%08x, diff=%10d, queue_len=%d\n", + __func__, + cb_pos->timestamp, cb_new->timestamp, + cb_new->timestamp - cb_pos->timestamp, + skb_queue_len(head)); + + if (compare(pos, new) < 0) + continue; + insert = pos; + break; + } + if (!insert) + __skb_queue_head(head, new); + else + __skb_queue_after(head, insert, new); +} + +static int can_rx_offload_compare(struct sk_buff *a, struct sk_buff *b) +{ + const struct can_rx_offload_cb *cb_a, *cb_b; + + cb_a = can_rx_offload_get_cb(a); + cb_b = can_rx_offload_get_cb(b); + + /* Subtract two u32 and return result as int, to keep + * difference steady around the u32 overflow. + */ + return cb_b->timestamp - cb_a->timestamp; +} + +/** + * can_rx_offload_offload_one() - Read one CAN frame from HW + * @offload: pointer to rx_offload context + * @n: number of mailbox to read + * + * The task of this function is to read a CAN frame from mailbox @n + * from the device and return the mailbox's content as a struct + * sk_buff. + * + * If the struct can_rx_offload::skb_queue exceeds the maximal queue + * length (struct can_rx_offload::skb_queue_len_max) or no skb can be + * allocated, the mailbox contents is discarded by reading it into an + * overflow buffer. This way the mailbox is marked as free by the + * driver. + * + * Return: A pointer to skb containing the CAN frame on success. + * + * NULL if the mailbox @n is empty. + * + * ERR_PTR() in case of an error + */ +static struct sk_buff * +can_rx_offload_offload_one(struct can_rx_offload *offload, unsigned int n) +{ + struct sk_buff *skb; + struct can_rx_offload_cb *cb; + bool drop = false; + u32 timestamp; + + /* If queue is full drop frame */ + if (unlikely(skb_queue_len(&offload->skb_queue) > + offload->skb_queue_len_max)) + drop = true; + + skb = offload->mailbox_read(offload, n, ×tamp, drop); + /* Mailbox was empty. */ + if (unlikely(!skb)) + return NULL; + + /* There was a problem reading the mailbox, propagate + * error value. + */ + if (IS_ERR(skb)) { + offload->dev->stats.rx_dropped++; + offload->dev->stats.rx_fifo_errors++; + + return skb; + } + + /* Mailbox was read. */ + cb = can_rx_offload_get_cb(skb); + cb->timestamp = timestamp; + + return skb; +} + +int can_rx_offload_irq_offload_timestamp(struct can_rx_offload *offload, + u64 pending) +{ + unsigned int i; + int received = 0; + + for (i = offload->mb_first; + can_rx_offload_le(offload, i, offload->mb_last); + can_rx_offload_inc(offload, &i)) { + struct sk_buff *skb; + + if (!(pending & BIT_ULL(i))) + continue; + + skb = can_rx_offload_offload_one(offload, i); + if (IS_ERR_OR_NULL(skb)) + continue; + + __skb_queue_add_sort(&offload->skb_irq_queue, skb, + can_rx_offload_compare); + received++; + } + + return received; +} +EXPORT_SYMBOL_GPL(can_rx_offload_irq_offload_timestamp); + +int can_rx_offload_irq_offload_fifo(struct can_rx_offload *offload) +{ + struct sk_buff *skb; + int received = 0; + + while (1) { + skb = can_rx_offload_offload_one(offload, 0); + if (IS_ERR(skb)) + continue; + if (!skb) + break; + + __skb_queue_tail(&offload->skb_irq_queue, skb); + received++; + } + + return received; +} +EXPORT_SYMBOL_GPL(can_rx_offload_irq_offload_fifo); + +int can_rx_offload_queue_timestamp(struct can_rx_offload *offload, + struct sk_buff *skb, u32 timestamp) +{ + struct can_rx_offload_cb *cb; + + if (skb_queue_len(&offload->skb_queue) > + offload->skb_queue_len_max) { + dev_kfree_skb_any(skb); + return -ENOBUFS; + } + + cb = can_rx_offload_get_cb(skb); + cb->timestamp = timestamp; + + __skb_queue_add_sort(&offload->skb_irq_queue, skb, + can_rx_offload_compare); + + return 0; +} +EXPORT_SYMBOL_GPL(can_rx_offload_queue_timestamp); + +unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload, + unsigned int idx, u32 timestamp, + unsigned int *frame_len_ptr) +{ + struct net_device *dev = offload->dev; + struct net_device_stats *stats = &dev->stats; + struct sk_buff *skb; + unsigned int len; + int err; + + skb = __can_get_echo_skb(dev, idx, &len, frame_len_ptr); + if (!skb) + return 0; + + err = can_rx_offload_queue_timestamp(offload, skb, timestamp); + if (err) { + stats->rx_errors++; + stats->tx_fifo_errors++; + } + + return len; +} +EXPORT_SYMBOL_GPL(can_rx_offload_get_echo_skb); + +int can_rx_offload_queue_tail(struct can_rx_offload *offload, + struct sk_buff *skb) +{ + if (skb_queue_len(&offload->skb_queue) > + offload->skb_queue_len_max) { + dev_kfree_skb_any(skb); + return -ENOBUFS; + } + + __skb_queue_tail(&offload->skb_irq_queue, skb); + + return 0; +} +EXPORT_SYMBOL_GPL(can_rx_offload_queue_tail); + +void can_rx_offload_irq_finish(struct can_rx_offload *offload) +{ + unsigned long flags; + int queue_len; + + if (skb_queue_empty_lockless(&offload->skb_irq_queue)) + return; + + spin_lock_irqsave(&offload->skb_queue.lock, flags); + skb_queue_splice_tail_init(&offload->skb_irq_queue, &offload->skb_queue); + spin_unlock_irqrestore(&offload->skb_queue.lock, flags); + + queue_len = skb_queue_len(&offload->skb_queue); + if (queue_len > offload->skb_queue_len_max / 8) + netdev_dbg(offload->dev, "%s: queue_len=%d\n", + __func__, queue_len); + + napi_schedule(&offload->napi); +} +EXPORT_SYMBOL_GPL(can_rx_offload_irq_finish); + +void can_rx_offload_threaded_irq_finish(struct can_rx_offload *offload) +{ + unsigned long flags; + int queue_len; + + if (skb_queue_empty_lockless(&offload->skb_irq_queue)) + return; + + spin_lock_irqsave(&offload->skb_queue.lock, flags); + skb_queue_splice_tail_init(&offload->skb_irq_queue, &offload->skb_queue); + spin_unlock_irqrestore(&offload->skb_queue.lock, flags); + + queue_len = skb_queue_len(&offload->skb_queue); + if (queue_len > offload->skb_queue_len_max / 8) + netdev_dbg(offload->dev, "%s: queue_len=%d\n", + __func__, queue_len); + + local_bh_disable(); + napi_schedule(&offload->napi); + local_bh_enable(); +} +EXPORT_SYMBOL_GPL(can_rx_offload_threaded_irq_finish); + +static int can_rx_offload_init_queue(struct net_device *dev, + struct can_rx_offload *offload, + unsigned int weight) +{ + offload->dev = dev; + + /* Limit queue len to 4x the weight (rounded to next power of two) */ + offload->skb_queue_len_max = 2 << fls(weight); + offload->skb_queue_len_max *= 4; + skb_queue_head_init(&offload->skb_queue); + __skb_queue_head_init(&offload->skb_irq_queue); + + netif_napi_add_weight(dev, &offload->napi, can_rx_offload_napi_poll, + weight); + + dev_dbg(dev->dev.parent, "%s: skb_queue_len_max=%d\n", + __func__, offload->skb_queue_len_max); + + return 0; +} + +int can_rx_offload_add_timestamp(struct net_device *dev, + struct can_rx_offload *offload) +{ + unsigned int weight; + + if (offload->mb_first > BITS_PER_LONG_LONG || + offload->mb_last > BITS_PER_LONG_LONG || !offload->mailbox_read) + return -EINVAL; + + if (offload->mb_first < offload->mb_last) { + offload->inc = true; + weight = offload->mb_last - offload->mb_first; + } else { + offload->inc = false; + weight = offload->mb_first - offload->mb_last; + } + + return can_rx_offload_init_queue(dev, offload, weight); +} +EXPORT_SYMBOL_GPL(can_rx_offload_add_timestamp); + +int can_rx_offload_add_fifo(struct net_device *dev, + struct can_rx_offload *offload, unsigned int weight) +{ + if (!offload->mailbox_read) + return -EINVAL; + + return can_rx_offload_init_queue(dev, offload, weight); +} +EXPORT_SYMBOL_GPL(can_rx_offload_add_fifo); + +int can_rx_offload_add_manual(struct net_device *dev, + struct can_rx_offload *offload, + unsigned int weight) +{ + if (offload->mailbox_read) + return -EINVAL; + + return can_rx_offload_init_queue(dev, offload, weight); +} +EXPORT_SYMBOL_GPL(can_rx_offload_add_manual); + +void can_rx_offload_enable(struct can_rx_offload *offload) +{ + napi_enable(&offload->napi); +} +EXPORT_SYMBOL_GPL(can_rx_offload_enable); + +void can_rx_offload_del(struct can_rx_offload *offload) +{ + netif_napi_del(&offload->napi); + skb_queue_purge(&offload->skb_queue); + __skb_queue_purge(&offload->skb_irq_queue); +} +EXPORT_SYMBOL_GPL(can_rx_offload_del); diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c new file mode 100644 index 000000000..3ebd4f779 --- /dev/null +++ b/drivers/net/can/dev/skb.c @@ -0,0 +1,374 @@ +// 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> + */ + +#include <linux/can/dev.h> +#include <linux/module.h> + +#define MOD_DESC "CAN device driver interface" + +MODULE_DESCRIPTION(MOD_DESC); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); + +/* Local echo of CAN messages + * + * CAN network devices *should* support a local echo functionality + * (see Documentation/networking/can.rst). To test the handling of CAN + * interfaces that do not support the local echo both driver types are + * implemented. In the case that the driver does not support the echo + * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core + * to perform the echo as a fallback solution. + */ +void can_flush_echo_skb(struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + struct net_device_stats *stats = &dev->stats; + int i; + + for (i = 0; i < priv->echo_skb_max; i++) { + if (priv->echo_skb[i]) { + kfree_skb(priv->echo_skb[i]); + priv->echo_skb[i] = NULL; + stats->tx_dropped++; + stats->tx_aborted_errors++; + } + } +} + +/* Put the skb on the stack to be looped backed locally lateron + * + * The function is typically called in the start_xmit function + * of the device driver. The driver must protect access to + * priv->echo_skb, if necessary. + */ +int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, + unsigned int idx, unsigned int frame_len) +{ + struct can_priv *priv = netdev_priv(dev); + + if (idx >= priv->echo_skb_max) { + netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n", + __func__, idx, priv->echo_skb_max); + return -EINVAL; + } + + /* check flag whether this packet has to be looped back */ + if (!(dev->flags & IFF_ECHO) || + (skb->protocol != htons(ETH_P_CAN) && + skb->protocol != htons(ETH_P_CANFD) && + skb->protocol != htons(ETH_P_CANXL))) { + kfree_skb(skb); + return 0; + } + + if (!priv->echo_skb[idx]) { + skb = can_create_echo_skb(skb); + if (!skb) + return -ENOMEM; + + /* make settings for echo to reduce code in irq context */ + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->dev = dev; + + /* save frame_len to reuse it when transmission is completed */ + can_skb_prv(skb)->frame_len = frame_len; + + if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) + skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS; + + skb_tx_timestamp(skb); + + /* save this skb for tx interrupt echo handling */ + priv->echo_skb[idx] = skb; + } else { + /* locking problem with netif_stop_queue() ?? */ + netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx); + kfree_skb(skb); + return -EBUSY; + } + + return 0; +} +EXPORT_SYMBOL_GPL(can_put_echo_skb); + +struct sk_buff * +__can_get_echo_skb(struct net_device *dev, unsigned int idx, + unsigned int *len_ptr, unsigned int *frame_len_ptr) +{ + struct can_priv *priv = netdev_priv(dev); + + if (idx >= priv->echo_skb_max) { + netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n", + __func__, idx, priv->echo_skb_max); + return NULL; + } + + if (priv->echo_skb[idx]) { + /* Using "struct canfd_frame::len" for the frame + * length is supported on both CAN and CANFD frames. + */ + struct sk_buff *skb = priv->echo_skb[idx]; + struct can_skb_priv *can_skb_priv = can_skb_prv(skb); + + if (skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS) + skb_tstamp_tx(skb, skb_hwtstamps(skb)); + + /* get the real payload length for netdev statistics */ + *len_ptr = can_skb_get_data_len(skb); + + if (frame_len_ptr) + *frame_len_ptr = can_skb_priv->frame_len; + + priv->echo_skb[idx] = NULL; + + if (skb->pkt_type == PACKET_LOOPBACK) { + skb->pkt_type = PACKET_BROADCAST; + } else { + dev_consume_skb_any(skb); + return NULL; + } + + return skb; + } + + return NULL; +} + +/* Get the skb from the stack and loop it back locally + * + * The function is typically called when the TX done interrupt + * is handled in the device driver. The driver must protect + * access to priv->echo_skb, if necessary. + */ +unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx, + unsigned int *frame_len_ptr) +{ + struct sk_buff *skb; + unsigned int len; + + skb = __can_get_echo_skb(dev, idx, &len, frame_len_ptr); + if (!skb) + return 0; + + skb_get(skb); + if (netif_rx(skb) == NET_RX_SUCCESS) + dev_consume_skb_any(skb); + else + dev_kfree_skb_any(skb); + + return len; +} +EXPORT_SYMBOL_GPL(can_get_echo_skb); + +/* Remove the skb from the stack and free it. + * + * The function is typically called when TX failed. + */ +void can_free_echo_skb(struct net_device *dev, unsigned int idx, + unsigned int *frame_len_ptr) +{ + struct can_priv *priv = netdev_priv(dev); + + if (idx >= priv->echo_skb_max) { + netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n", + __func__, idx, priv->echo_skb_max); + return; + } + + if (priv->echo_skb[idx]) { + struct sk_buff *skb = priv->echo_skb[idx]; + struct can_skb_priv *can_skb_priv = can_skb_prv(skb); + + if (frame_len_ptr) + *frame_len_ptr = can_skb_priv->frame_len; + + dev_kfree_skb_any(skb); + priv->echo_skb[idx] = NULL; + } +} +EXPORT_SYMBOL_GPL(can_free_echo_skb); + +/* fill common values for CAN sk_buffs */ +static void init_can_skb_reserve(struct sk_buff *skb) +{ + skb->pkt_type = PACKET_BROADCAST; + skb->ip_summed = CHECKSUM_UNNECESSARY; + + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + + can_skb_reserve(skb); + can_skb_prv(skb)->skbcnt = 0; +} + +struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) +{ + struct sk_buff *skb; + + skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + + sizeof(struct can_frame)); + if (unlikely(!skb)) { + *cf = NULL; + + return NULL; + } + + skb->protocol = htons(ETH_P_CAN); + init_can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + + *cf = skb_put_zero(skb, sizeof(struct can_frame)); + + return skb; +} +EXPORT_SYMBOL_GPL(alloc_can_skb); + +struct sk_buff *alloc_canfd_skb(struct net_device *dev, + struct canfd_frame **cfd) +{ + struct sk_buff *skb; + + skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + + sizeof(struct canfd_frame)); + if (unlikely(!skb)) { + *cfd = NULL; + + return NULL; + } + + skb->protocol = htons(ETH_P_CANFD); + init_can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + + *cfd = skb_put_zero(skb, sizeof(struct canfd_frame)); + + /* set CAN FD flag by default */ + (*cfd)->flags = CANFD_FDF; + + return skb; +} +EXPORT_SYMBOL_GPL(alloc_canfd_skb); + +struct sk_buff *alloc_canxl_skb(struct net_device *dev, + struct canxl_frame **cxl, + unsigned int data_len) +{ + struct sk_buff *skb; + + if (data_len < CANXL_MIN_DLEN || data_len > CANXL_MAX_DLEN) + goto out_error; + + skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + + CANXL_HDR_SIZE + data_len); + if (unlikely(!skb)) + goto out_error; + + skb->protocol = htons(ETH_P_CANXL); + init_can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + + *cxl = skb_put_zero(skb, CANXL_HDR_SIZE + data_len); + + /* set CAN XL flag and length information by default */ + (*cxl)->flags = CANXL_XLF; + (*cxl)->len = data_len; + + return skb; + +out_error: + *cxl = NULL; + + return NULL; +} +EXPORT_SYMBOL_GPL(alloc_canxl_skb); + +struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) +{ + struct sk_buff *skb; + + skb = alloc_can_skb(dev, cf); + if (unlikely(!skb)) + return NULL; + + (*cf)->can_id = CAN_ERR_FLAG; + (*cf)->len = CAN_ERR_DLC; + + return skb; +} +EXPORT_SYMBOL_GPL(alloc_can_err_skb); + +/* Check for outgoing skbs that have not been created by the CAN subsystem */ +static bool can_skb_headroom_valid(struct net_device *dev, struct sk_buff *skb) +{ + /* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */ + if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv))) + return false; + + /* af_packet does not apply CAN skb specific settings */ + if (skb->ip_summed == CHECKSUM_NONE) { + /* init headroom */ + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + + /* perform proper loopback on capable devices */ + if (dev->flags & IFF_ECHO) + skb->pkt_type = PACKET_LOOPBACK; + else + skb->pkt_type = PACKET_HOST; + + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + + /* set CANFD_FDF flag for CAN FD frames */ + if (can_is_canfd_skb(skb)) { + struct canfd_frame *cfd; + + cfd = (struct canfd_frame *)skb->data; + cfd->flags |= CANFD_FDF; + } + } + + return true; +} + +/* Drop a given socketbuffer if it does not contain a valid CAN frame. */ +bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb) +{ + switch (ntohs(skb->protocol)) { + case ETH_P_CAN: + if (!can_is_can_skb(skb)) + goto inval_skb; + break; + + case ETH_P_CANFD: + if (!can_is_canfd_skb(skb)) + goto inval_skb; + break; + + case ETH_P_CANXL: + if (!can_is_canxl_skb(skb)) + goto inval_skb; + break; + + default: + goto inval_skb; + } + + if (!can_skb_headroom_valid(dev, skb)) + goto inval_skb; + + return false; + +inval_skb: + kfree_skb(skb); + dev->stats.tx_dropped++; + return true; +} +EXPORT_SYMBOL_GPL(can_dropped_invalid_skb); |