Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

3 files changed, 599 insertions, 0 deletions

diff --git a/drivers/staging/most/net/Kconfig b/drivers/staging/most/net/Kconfig
new file mode 100644
index 000000000..ed8ac7e07
--- /dev/null
+++ b/drivers/staging/most/net/Kconfig
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# MOST Networking configuration
+#
+
+config MOST_NET
+	tristate "Net"
+	depends on NET
+
+	help
+	  Say Y here if you want to commumicate via a networking device.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called most_net.
diff --git a/drivers/staging/most/net/Makefile b/drivers/staging/most/net/Makefile
new file mode 100644
index 000000000..1582c97eb
--- /dev/null
+++ b/drivers/staging/most/net/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_MOST_NET) += most_net.o
+
+most_net-objs := net.o
diff --git a/drivers/staging/most/net/net.c b/drivers/staging/most/net/net.c
new file mode 100644
index 000000000..1d1fe8bff
--- /dev/null
+++ b/drivers/staging/most/net/net.c
@@ -0,0 +1,581 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * net.c - Networking component for Mostcore
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/kobject.h>
+#include <linux/most.h>
+
+#define MEP_HDR_LEN 8
+#define MDP_HDR_LEN 16
+#define MAMAC_DATA_LEN (1024 - MDP_HDR_LEN)
+
+#define PMHL 5
+
+#define PMS_TELID_UNSEGM_MAMAC	0x0A
+#define PMS_FIFONO_MDP		0x01
+#define PMS_FIFONO_MEP		0x04
+#define PMS_MSGTYPE_DATA	0x04
+#define PMS_DEF_PRIO		0
+#define MEP_DEF_RETRY		15
+
+#define PMS_FIFONO_MASK		0x07
+#define PMS_FIFONO_SHIFT	3
+#define PMS_RETRY_SHIFT		4
+#define PMS_TELID_MASK		0x0F
+#define PMS_TELID_SHIFT		4
+
+#define HB(value)		((u8)((u16)(value) >> 8))
+#define LB(value)		((u8)(value))
+
+#define EXTRACT_BIT_SET(bitset_name, value) \
+	(((value) >> bitset_name##_SHIFT) & bitset_name##_MASK)
+
+#define PMS_IS_MEP(buf, len) \
+	((len) > MEP_HDR_LEN && \
+	 EXTRACT_BIT_SET(PMS_FIFONO, (buf)[3]) == PMS_FIFONO_MEP)
+
+static inline bool pms_is_mamac(char *buf, u32 len)
+{
+	return (len > MDP_HDR_LEN &&
+		EXTRACT_BIT_SET(PMS_FIFONO, buf[3]) == PMS_FIFONO_MDP &&
+		EXTRACT_BIT_SET(PMS_TELID, buf[14]) == PMS_TELID_UNSEGM_MAMAC);
+}
+
+struct net_dev_channel {
+	bool linked;
+	int ch_id;
+};
+
+struct net_dev_context {
+	struct most_interface *iface;
+	bool is_mamac;
+	struct net_device *dev;
+	struct net_dev_channel rx;
+	struct net_dev_channel tx;
+	struct list_head list;
+};
+
+static LIST_HEAD(net_devices);
+static DEFINE_MUTEX(probe_disc_mt); /* ch->linked = true, most_nd_open */
+static DEFINE_SPINLOCK(list_lock); /* list_head, ch->linked = false, dev_hold */
+static struct most_component comp;
+
+static int skb_to_mamac(const struct sk_buff *skb, struct mbo *mbo)
+{
+	u8 *buff = mbo->virt_address;
+	static const u8 broadcast[] = { 0x03, 0xFF };
+	const u8 *dest_addr = skb->data + 4;
+	const u8 *eth_type = skb->data + 12;
+	unsigned int payload_len = skb->len - ETH_HLEN;
+	unsigned int mdp_len = payload_len + MDP_HDR_LEN;
+
+	if (mdp_len < skb->len) {
+		pr_err("drop: too large packet! (%u)\n", skb->len);
+		return -EINVAL;
+	}
+
+	if (mbo->buffer_length < mdp_len) {
+		pr_err("drop: too small buffer! (%d for %d)\n",
+		       mbo->buffer_length, mdp_len);
+		return -EINVAL;
+	}
+
+	if (skb->len < ETH_HLEN) {
+		pr_err("drop: too small packet! (%d)\n", skb->len);
+		return -EINVAL;
+	}
+
+	if (dest_addr[0] == 0xFF && dest_addr[1] == 0xFF)
+		dest_addr = broadcast;
+
+	*buff++ = HB(mdp_len - 2);
+	*buff++ = LB(mdp_len - 2);
+
+	*buff++ = PMHL;
+	*buff++ = (PMS_FIFONO_MDP << PMS_FIFONO_SHIFT) | PMS_MSGTYPE_DATA;
+	*buff++ = PMS_DEF_PRIO;
+	*buff++ = dest_addr[0];
+	*buff++ = dest_addr[1];
+	*buff++ = 0x00;
+
+	*buff++ = HB(payload_len + 6);
+	*buff++ = LB(payload_len + 6);
+
+	/* end of FPH here */
+
+	*buff++ = eth_type[0];
+	*buff++ = eth_type[1];
+	*buff++ = 0;
+	*buff++ = 0;
+
+	*buff++ = PMS_TELID_UNSEGM_MAMAC << 4 | HB(payload_len);
+	*buff++ = LB(payload_len);
+
+	memcpy(buff, skb->data + ETH_HLEN, payload_len);
+	mbo->buffer_length = mdp_len;
+	return 0;
+}
+
+static int skb_to_mep(const struct sk_buff *skb, struct mbo *mbo)
+{
+	u8 *buff = mbo->virt_address;
+	unsigned int mep_len = skb->len + MEP_HDR_LEN;
+
+	if (mep_len < skb->len) {
+		pr_err("drop: too large packet! (%u)\n", skb->len);
+		return -EINVAL;
+	}
+
+	if (mbo->buffer_length < mep_len) {
+		pr_err("drop: too small buffer! (%d for %d)\n",
+		       mbo->buffer_length, mep_len);
+		return -EINVAL;
+	}
+
+	*buff++ = HB(mep_len - 2);
+	*buff++ = LB(mep_len - 2);
+
+	*buff++ = PMHL;
+	*buff++ = (PMS_FIFONO_MEP << PMS_FIFONO_SHIFT) | PMS_MSGTYPE_DATA;
+	*buff++ = (MEP_DEF_RETRY << PMS_RETRY_SHIFT) | PMS_DEF_PRIO;
+	*buff++ = 0;
+	*buff++ = 0;
+	*buff++ = 0;
+
+	memcpy(buff, skb->data, skb->len);
+	mbo->buffer_length = mep_len;
+	return 0;
+}
+
+static int most_nd_set_mac_address(struct net_device *dev, void *p)
+{
+	struct net_dev_context *nd = netdev_priv(dev);
+	int err = eth_mac_addr(dev, p);
+
+	if (err)
+		return err;
+
+	nd->is_mamac =
+		(dev->dev_addr[0] == 0 && dev->dev_addr[1] == 0 &&
+		 dev->dev_addr[2] == 0 && dev->dev_addr[3] == 0);
+
+	/*
+	 * Set default MTU for the given packet type.
+	 * It is still possible to change MTU using ip tools afterwards.
+	 */
+	dev->mtu = nd->is_mamac ? MAMAC_DATA_LEN : ETH_DATA_LEN;
+
+	return 0;
+}
+
+static void on_netinfo(struct most_interface *iface,
+		       unsigned char link_stat, unsigned char *mac_addr);
+
+static int most_nd_open(struct net_device *dev)
+{
+	struct net_dev_context *nd = netdev_priv(dev);
+	int ret = 0;
+
+	mutex_lock(&probe_disc_mt);
+
+	if (most_start_channel(nd->iface, nd->rx.ch_id, &comp)) {
+		netdev_err(dev, "most_start_channel() failed\n");
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	if (most_start_channel(nd->iface, nd->tx.ch_id, &comp)) {
+		netdev_err(dev, "most_start_channel() failed\n");
+		most_stop_channel(nd->iface, nd->rx.ch_id, &comp);
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	netif_carrier_off(dev);
+	if (is_valid_ether_addr(dev->dev_addr))
+		netif_dormant_off(dev);
+	else
+		netif_dormant_on(dev);
+	netif_wake_queue(dev);
+	if (nd->iface->request_netinfo)
+		nd->iface->request_netinfo(nd->iface, nd->tx.ch_id, on_netinfo);
+
+unlock:
+	mutex_unlock(&probe_disc_mt);
+	return ret;
+}
+
+static int most_nd_stop(struct net_device *dev)
+{
+	struct net_dev_context *nd = netdev_priv(dev);
+
+	netif_stop_queue(dev);
+	if (nd->iface->request_netinfo)
+		nd->iface->request_netinfo(nd->iface, nd->tx.ch_id, NULL);
+	most_stop_channel(nd->iface, nd->rx.ch_id, &comp);
+	most_stop_channel(nd->iface, nd->tx.ch_id, &comp);
+
+	return 0;
+}
+
+static netdev_tx_t most_nd_start_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	struct net_dev_context *nd = netdev_priv(dev);
+	struct mbo *mbo;
+	int ret;
+
+	mbo = most_get_mbo(nd->iface, nd->tx.ch_id, &comp);
+
+	if (!mbo) {
+		netif_stop_queue(dev);
+		dev->stats.tx_fifo_errors++;
+		return NETDEV_TX_BUSY;
+	}
+
+	if (nd->is_mamac)
+		ret = skb_to_mamac(skb, mbo);
+	else
+		ret = skb_to_mep(skb, mbo);
+
+	if (ret) {
+		most_put_mbo(mbo);
+		dev->stats.tx_dropped++;
+		kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+
+	most_submit_mbo(mbo);
+	dev->stats.tx_packets++;
+	dev->stats.tx_bytes += skb->len;
+	kfree_skb(skb);
+	return NETDEV_TX_OK;
+}
+
+static const struct net_device_ops most_nd_ops = {
+	.ndo_open = most_nd_open,
+	.ndo_stop = most_nd_stop,
+	.ndo_start_xmit = most_nd_start_xmit,
+	.ndo_set_mac_address = most_nd_set_mac_address,
+};
+
+static void most_nd_setup(struct net_device *dev)
+{
+	ether_setup(dev);
+	dev->netdev_ops = &most_nd_ops;
+}
+
+static struct net_dev_context *get_net_dev(struct most_interface *iface)
+{
+	struct net_dev_context *nd;
+
+	list_for_each_entry(nd, &net_devices, list)
+		if (nd->iface == iface)
+			return nd;
+	return NULL;
+}
+
+static struct net_dev_context *get_net_dev_hold(struct most_interface *iface)
+{
+	struct net_dev_context *nd;
+	unsigned long flags;
+
+	spin_lock_irqsave(&list_lock, flags);
+	nd = get_net_dev(iface);
+	if (nd && nd->rx.linked && nd->tx.linked)
+		dev_hold(nd->dev);
+	else
+		nd = NULL;
+	spin_unlock_irqrestore(&list_lock, flags);
+	return nd;
+}
+
+static int comp_probe_channel(struct most_interface *iface, int channel_idx,
+			      struct most_channel_config *ccfg, char *name,
+			      char *args)
+{
+	struct net_dev_context *nd;
+	struct net_dev_channel *ch;
+	struct net_device *dev;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!iface)
+		return -EINVAL;
+
+	if (ccfg->data_type != MOST_CH_ASYNC)
+		return -EINVAL;
+
+	mutex_lock(&probe_disc_mt);
+	nd = get_net_dev(iface);
+	if (!nd) {
+		dev = alloc_netdev(sizeof(struct net_dev_context), "meth%d",
+				   NET_NAME_UNKNOWN, most_nd_setup);
+		if (!dev) {
+			ret = -ENOMEM;
+			goto unlock;
+		}
+
+		nd = netdev_priv(dev);
+		nd->iface = iface;
+		nd->dev = dev;
+
+		spin_lock_irqsave(&list_lock, flags);
+		list_add(&nd->list, &net_devices);
+		spin_unlock_irqrestore(&list_lock, flags);
+
+		ch = ccfg->direction == MOST_CH_TX ? &nd->tx : &nd->rx;
+	} else {
+		ch = ccfg->direction == MOST_CH_TX ? &nd->tx : &nd->rx;
+		if (ch->linked) {
+			pr_err("direction is allocated\n");
+			ret = -EINVAL;
+			goto unlock;
+		}
+
+		if (register_netdev(nd->dev)) {
+			pr_err("register_netdev() failed\n");
+			ret = -EINVAL;
+			goto unlock;
+		}
+	}
+	ch->ch_id = channel_idx;
+	ch->linked = true;
+
+unlock:
+	mutex_unlock(&probe_disc_mt);
+	return ret;
+}
+
+static int comp_disconnect_channel(struct most_interface *iface,
+				   int channel_idx)
+{
+	struct net_dev_context *nd;
+	struct net_dev_channel *ch;
+	unsigned long flags;
+	int ret = 0;
+
+	mutex_lock(&probe_disc_mt);
+	nd = get_net_dev(iface);
+	if (!nd) {
+		ret = -EINVAL;
+		goto unlock;
+	}
+
+	if (nd->rx.linked && channel_idx == nd->rx.ch_id) {
+		ch = &nd->rx;
+	} else if (nd->tx.linked && channel_idx == nd->tx.ch_id) {
+		ch = &nd->tx;
+	} else {
+		ret = -EINVAL;
+		goto unlock;
+	}
+
+	if (nd->rx.linked && nd->tx.linked) {
+		spin_lock_irqsave(&list_lock, flags);
+		ch->linked = false;
+		spin_unlock_irqrestore(&list_lock, flags);
+
+		/*
+		 * do not call most_stop_channel() here, because channels are
+		 * going to be closed in ndo_stop() after unregister_netdev()
+		 */
+		unregister_netdev(nd->dev);
+	} else {
+		spin_lock_irqsave(&list_lock, flags);
+		list_del(&nd->list);
+		spin_unlock_irqrestore(&list_lock, flags);
+
+		free_netdev(nd->dev);
+	}
+
+unlock:
+	mutex_unlock(&probe_disc_mt);
+	return ret;
+}
+
+static int comp_resume_tx_channel(struct most_interface *iface,
+				  int channel_idx)
+{
+	struct net_dev_context *nd;
+
+	nd = get_net_dev_hold(iface);
+	if (!nd)
+		return 0;
+
+	if (nd->tx.ch_id != channel_idx)
+		goto put_nd;
+
+	netif_wake_queue(nd->dev);
+
+put_nd:
+	dev_put(nd->dev);
+	return 0;
+}
+
+static int comp_rx_data(struct mbo *mbo)
+{
+	const u32 zero = 0;
+	struct net_dev_context *nd;
+	char *buf = mbo->virt_address;
+	u32 len = mbo->processed_length;
+	struct sk_buff *skb;
+	struct net_device *dev;
+	unsigned int skb_len;
+	int ret = 0;
+
+	nd = get_net_dev_hold(mbo->ifp);
+	if (!nd)
+		return -EIO;
+
+	if (nd->rx.ch_id != mbo->hdm_channel_id) {
+		ret = -EIO;
+		goto put_nd;
+	}
+
+	dev = nd->dev;
+
+	if (nd->is_mamac) {
+		if (!pms_is_mamac(buf, len)) {
+			ret = -EIO;
+			goto put_nd;
+		}
+
+		skb = dev_alloc_skb(len - MDP_HDR_LEN + 2 * ETH_ALEN + 2);
+	} else {
+		if (!PMS_IS_MEP(buf, len)) {
+			ret = -EIO;
+			goto put_nd;
+		}
+
+		skb = dev_alloc_skb(len - MEP_HDR_LEN);
+	}
+
+	if (!skb) {
+		dev->stats.rx_dropped++;
+		pr_err_once("drop packet: no memory for skb\n");
+		goto out;
+	}
+
+	skb->dev = dev;
+
+	if (nd->is_mamac) {
+		/* dest */
+		ether_addr_copy(skb_put(skb, ETH_ALEN), dev->dev_addr);
+
+		/* src */
+		skb_put_data(skb, &zero, 4);
+		skb_put_data(skb, buf + 5, 2);
+
+		/* eth type */
+		skb_put_data(skb, buf + 10, 2);
+
+		buf += MDP_HDR_LEN;
+		len -= MDP_HDR_LEN;
+	} else {
+		buf += MEP_HDR_LEN;
+		len -= MEP_HDR_LEN;
+	}
+
+	skb_put_data(skb, buf, len);
+	skb->protocol = eth_type_trans(skb, dev);
+	skb_len = skb->len;
+	if (netif_rx(skb) == NET_RX_SUCCESS) {
+		dev->stats.rx_packets++;
+		dev->stats.rx_bytes += skb_len;
+	} else {
+		dev->stats.rx_dropped++;
+	}
+
+out:
+	most_put_mbo(mbo);
+
+put_nd:
+	dev_put(nd->dev);
+	return ret;
+}
+
+static struct most_component comp = {
+	.mod = THIS_MODULE,
+	.name = "net",
+	.probe_channel = comp_probe_channel,
+	.disconnect_channel = comp_disconnect_channel,
+	.tx_completion = comp_resume_tx_channel,
+	.rx_completion = comp_rx_data,
+};
+
+static int __init most_net_init(void)
+{
+	int err;
+
+	err = most_register_component(&comp);
+	if (err)
+		return err;
+	err = most_register_configfs_subsys(&comp);
+	if (err) {
+		most_deregister_component(&comp);
+		return err;
+	}
+	return 0;
+}
+
+static void __exit most_net_exit(void)
+{
+	most_deregister_configfs_subsys(&comp);
+	most_deregister_component(&comp);
+}
+
+/**
+ * on_netinfo - callback for HDM to be informed about HW's MAC
+ * @iface: most interface instance
+ * @link_stat: link status
+ * @mac_addr: MAC address
+ */
+static void on_netinfo(struct most_interface *iface,
+		       unsigned char link_stat, unsigned char *mac_addr)
+{
+	struct net_dev_context *nd;
+	struct net_device *dev;
+	const u8 *m = mac_addr;
+
+	nd = get_net_dev_hold(iface);
+	if (!nd)
+		return;
+
+	dev = nd->dev;
+
+	if (link_stat)
+		netif_carrier_on(dev);
+	else
+		netif_carrier_off(dev);
+
+	if (m && is_valid_ether_addr(m)) {
+		if (!is_valid_ether_addr(dev->dev_addr)) {
+			netdev_info(dev, "set mac %pM\n", m);
+			eth_hw_addr_set(dev, m);
+			netif_dormant_off(dev);
+		} else if (!ether_addr_equal(dev->dev_addr, m)) {
+			netdev_warn(dev, "reject mac %pM\n", m);
+		}
+	}
+
+	dev_put(nd->dev);
+}
+
+module_init(most_net_init);
+module_exit(most_net_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>");
+MODULE_DESCRIPTION("Networking Component Module for Mostcore");