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().
  ...

1 files changed, 1219 insertions, 0 deletions

diff --git a/drivers/net/arcnet/arcnet.c b/drivers/net/arcnet/arcnet.c
new file mode 100644
index 000000000..1bad1866a
--- /dev/null
+++ b/drivers/net/arcnet/arcnet.c
@@ -0,0 +1,1219 @@
+/*
+ * Linux ARCnet driver - device-independent routines
+ *
+ * Written 1997 by David Woodhouse.
+ * Written 1994-1999 by Avery Pennarun.
+ * Written 1999-2000 by Martin Mares <mj@ucw.cz>.
+ * Derived from skeleton.c by Donald Becker.
+ *
+ * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
+ *  for sponsoring the further development of this driver.
+ *
+ * **********************
+ *
+ * The original copyright was as follows:
+ *
+ * skeleton.c Written 1993 by Donald Becker.
+ * Copyright 1993 United States Government as represented by the
+ * Director, National Security Agency.  This software may only be used
+ * and distributed according to the terms of the GNU General Public License as
+ * modified by SRC, incorporated herein by reference.
+ *
+ * **********************
+ *
+ * The change log is now in a file called ChangeLog in this directory.
+ *
+ * Sources:
+ *  - Crynwr arcnet.com/arcether.com packet drivers.
+ *  - arcnet.c v0.00 dated 1/1/94 and apparently by
+ *     Donald Becker - it didn't work :)
+ *  - skeleton.c v0.05 dated 11/16/93 by Donald Becker
+ *     (from Linux Kernel 1.1.45)
+ *  - RFC's 1201 and 1051 - re: TCP/IP over ARCnet
+ *  - The official ARCnet COM9026 data sheets (!) thanks to
+ *     Ken Cornetet <kcornete@nyx10.cs.du.edu>
+ *  - The official ARCnet COM20020 data sheets.
+ *  - Information on some more obscure ARCnet controller chips, thanks
+ *     to the nice people at SMSC.
+ *  - net/inet/eth.c (from kernel 1.1.50) for header-building info.
+ *  - Alternate Linux ARCnet source by V.Shergin <vsher@sao.stavropol.su>
+ *  - Textual information and more alternate source from Joachim Koenig
+ *     <jojo@repas.de>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <net/arp.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/errqueue.h>
+
+#include <linux/leds.h>
+
+#include "arcdevice.h"
+#include "com9026.h"
+
+/* "do nothing" functions for protocol drivers */
+static void null_rx(struct net_device *dev, int bufnum,
+		    struct archdr *pkthdr, int length);
+static int null_build_header(struct sk_buff *skb, struct net_device *dev,
+			     unsigned short type, uint8_t daddr);
+static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
+			   int length, int bufnum);
+
+static void arcnet_rx(struct net_device *dev, int bufnum);
+
+/* one ArcProto per possible proto ID.  None of the elements of
+ * arc_proto_map are allowed to be NULL; they will get set to
+ * arc_proto_default instead.  It also must not be NULL; if you would like
+ * to set it to NULL, set it to &arc_proto_null instead.
+ */
+struct ArcProto *arc_proto_map[256];
+EXPORT_SYMBOL(arc_proto_map);
+
+struct ArcProto *arc_proto_default;
+EXPORT_SYMBOL(arc_proto_default);
+
+struct ArcProto *arc_bcast_proto;
+EXPORT_SYMBOL(arc_bcast_proto);
+
+struct ArcProto *arc_raw_proto;
+EXPORT_SYMBOL(arc_raw_proto);
+
+static struct ArcProto arc_proto_null = {
+	.suffix		= '?',
+	.mtu		= XMTU,
+	.is_ip          = 0,
+	.rx		= null_rx,
+	.build_header	= null_build_header,
+	.prepare_tx	= null_prepare_tx,
+	.continue_tx    = NULL,
+	.ack_tx         = NULL
+};
+
+/* Exported function prototypes */
+int arcnet_debug = ARCNET_DEBUG;
+EXPORT_SYMBOL(arcnet_debug);
+
+/* Internal function prototypes */
+static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
+			 unsigned short type, const void *daddr,
+			 const void *saddr, unsigned len);
+static int go_tx(struct net_device *dev);
+
+static int debug = ARCNET_DEBUG;
+module_param(debug, int, 0);
+MODULE_LICENSE("GPL");
+
+static int __init arcnet_init(void)
+{
+	int count;
+
+	arcnet_debug = debug;
+
+	pr_info("arcnet loaded\n");
+
+	/* initialize the protocol map */
+	arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
+	for (count = 0; count < 256; count++)
+		arc_proto_map[count] = arc_proto_default;
+
+	if (BUGLVL(D_DURING))
+		pr_info("struct sizes: %zd %zd %zd %zd %zd\n",
+			sizeof(struct arc_hardware),
+			sizeof(struct arc_rfc1201),
+			sizeof(struct arc_rfc1051),
+			sizeof(struct arc_eth_encap),
+			sizeof(struct archdr));
+
+	return 0;
+}
+
+static void __exit arcnet_exit(void)
+{
+}
+
+module_init(arcnet_init);
+module_exit(arcnet_exit);
+
+/* Dump the contents of an sk_buff */
+#if ARCNET_DEBUG_MAX & D_SKB
+void arcnet_dump_skb(struct net_device *dev,
+		     struct sk_buff *skb, char *desc)
+{
+	char hdr[32];
+
+	/* dump the packet */
+	snprintf(hdr, sizeof(hdr), "%6s:%s skb->data:", dev->name, desc);
+	print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
+		       16, 1, skb->data, skb->len, true);
+}
+EXPORT_SYMBOL(arcnet_dump_skb);
+#endif
+
+/* Dump the contents of an ARCnet buffer */
+#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
+static void arcnet_dump_packet(struct net_device *dev, int bufnum,
+			       char *desc, int take_arcnet_lock)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+	int i, length;
+	unsigned long flags = 0;
+	static uint8_t buf[512];
+	char hdr[32];
+
+	/* hw.copy_from_card expects IRQ context so take the IRQ lock
+	 * to keep it single threaded
+	 */
+	if (take_arcnet_lock)
+		spin_lock_irqsave(&lp->lock, flags);
+
+	lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
+	if (take_arcnet_lock)
+		spin_unlock_irqrestore(&lp->lock, flags);
+
+	/* if the offset[0] byte is nonzero, this is a 256-byte packet */
+	length = (buf[2] ? 256 : 512);
+
+	/* dump the packet */
+	snprintf(hdr, sizeof(hdr), "%6s:%s packet dump:", dev->name, desc);
+	print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
+		       16, 1, buf, length, true);
+}
+
+#else
+
+#define arcnet_dump_packet(dev, bufnum, desc, take_arcnet_lock) do { } while (0)
+
+#endif
+
+/* Trigger a LED event in response to a ARCNET device event */
+void arcnet_led_event(struct net_device *dev, enum arcnet_led_event event)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+	unsigned long led_delay = 350;
+	unsigned long tx_delay = 50;
+
+	switch (event) {
+	case ARCNET_LED_EVENT_RECON:
+		led_trigger_blink_oneshot(lp->recon_led_trig,
+					  &led_delay, &led_delay, 0);
+		break;
+	case ARCNET_LED_EVENT_OPEN:
+		led_trigger_event(lp->tx_led_trig, LED_OFF);
+		led_trigger_event(lp->recon_led_trig, LED_OFF);
+		break;
+	case ARCNET_LED_EVENT_STOP:
+		led_trigger_event(lp->tx_led_trig, LED_OFF);
+		led_trigger_event(lp->recon_led_trig, LED_OFF);
+		break;
+	case ARCNET_LED_EVENT_TX:
+		led_trigger_blink_oneshot(lp->tx_led_trig,
+					  &tx_delay, &tx_delay, 0);
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(arcnet_led_event);
+
+static void arcnet_led_release(struct device *gendev, void *res)
+{
+	struct arcnet_local *lp = netdev_priv(to_net_dev(gendev));
+
+	led_trigger_unregister_simple(lp->tx_led_trig);
+	led_trigger_unregister_simple(lp->recon_led_trig);
+}
+
+/* Register ARCNET LED triggers for a arcnet device
+ *
+ * This is normally called from a driver's probe function
+ */
+void devm_arcnet_led_init(struct net_device *netdev, int index, int subid)
+{
+	struct arcnet_local *lp = netdev_priv(netdev);
+	void *res;
+
+	res = devres_alloc(arcnet_led_release, 0, GFP_KERNEL);
+	if (!res) {
+		netdev_err(netdev, "cannot register LED triggers\n");
+		return;
+	}
+
+	snprintf(lp->tx_led_trig_name, sizeof(lp->tx_led_trig_name),
+		 "arc%d-%d-tx", index, subid);
+	snprintf(lp->recon_led_trig_name, sizeof(lp->recon_led_trig_name),
+		 "arc%d-%d-recon", index, subid);
+
+	led_trigger_register_simple(lp->tx_led_trig_name,
+				    &lp->tx_led_trig);
+	led_trigger_register_simple(lp->recon_led_trig_name,
+				    &lp->recon_led_trig);
+
+	devres_add(&netdev->dev, res);
+}
+EXPORT_SYMBOL_GPL(devm_arcnet_led_init);
+
+/* Unregister a protocol driver from the arc_proto_map.  Protocol drivers
+ * are responsible for registering themselves, but the unregister routine
+ * is pretty generic so we'll do it here.
+ */
+void arcnet_unregister_proto(struct ArcProto *proto)
+{
+	int count;
+
+	if (arc_proto_default == proto)
+		arc_proto_default = &arc_proto_null;
+	if (arc_bcast_proto == proto)
+		arc_bcast_proto = arc_proto_default;
+	if (arc_raw_proto == proto)
+		arc_raw_proto = arc_proto_default;
+
+	for (count = 0; count < 256; count++) {
+		if (arc_proto_map[count] == proto)
+			arc_proto_map[count] = arc_proto_default;
+	}
+}
+EXPORT_SYMBOL(arcnet_unregister_proto);
+
+/* Add a buffer to the queue.  Only the interrupt handler is allowed to do
+ * this, unless interrupts are disabled.
+ *
+ * Note: we don't check for a full queue, since there aren't enough buffers
+ * to more than fill it.
+ */
+static void release_arcbuf(struct net_device *dev, int bufnum)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+	int i;
+
+	lp->buf_queue[lp->first_free_buf++] = bufnum;
+	lp->first_free_buf %= 5;
+
+	if (BUGLVL(D_DURING)) {
+		arc_printk(D_DURING, dev, "release_arcbuf: freed #%d; buffer queue is now: ",
+			   bufnum);
+		for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
+			arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
+		arc_cont(D_DURING, "\n");
+	}
+}
+
+/* Get a buffer from the queue.
+ * If this returns -1, there are no buffers available.
+ */
+static int get_arcbuf(struct net_device *dev)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+	int buf = -1, i;
+
+	if (!atomic_dec_and_test(&lp->buf_lock)) {
+		/* already in this function */
+		arc_printk(D_NORMAL, dev, "get_arcbuf: overlap (%d)!\n",
+			   lp->buf_lock.counter);
+	} else {			/* we can continue */
+		if (lp->next_buf >= 5)
+			lp->next_buf -= 5;
+
+		if (lp->next_buf == lp->first_free_buf) {
+			arc_printk(D_NORMAL, dev, "get_arcbuf: BUG: no buffers are available??\n");
+		} else {
+			buf = lp->buf_queue[lp->next_buf++];
+			lp->next_buf %= 5;
+		}
+	}
+
+	if (BUGLVL(D_DURING)) {
+		arc_printk(D_DURING, dev, "get_arcbuf: got #%d; buffer queue is now: ",
+			   buf);
+		for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
+			arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
+		arc_cont(D_DURING, "\n");
+	}
+
+	atomic_inc(&lp->buf_lock);
+	return buf;
+}
+
+static int choose_mtu(void)
+{
+	int count, mtu = 65535;
+
+	/* choose the smallest MTU of all available encaps */
+	for (count = 0; count < 256; count++) {
+		if (arc_proto_map[count] != &arc_proto_null &&
+		    arc_proto_map[count]->mtu < mtu) {
+			mtu = arc_proto_map[count]->mtu;
+		}
+	}
+
+	return mtu == 65535 ? XMTU : mtu;
+}
+
+static const struct header_ops arcnet_header_ops = {
+	.create = arcnet_header,
+};
+
+static const struct net_device_ops arcnet_netdev_ops = {
+	.ndo_open	= arcnet_open,
+	.ndo_stop	= arcnet_close,
+	.ndo_start_xmit = arcnet_send_packet,
+	.ndo_tx_timeout = arcnet_timeout,
+};
+
+/* Setup a struct device for ARCnet. */
+static void arcdev_setup(struct net_device *dev)
+{
+	dev->type = ARPHRD_ARCNET;
+	dev->netdev_ops = &arcnet_netdev_ops;
+	dev->header_ops = &arcnet_header_ops;
+	dev->hard_header_len = sizeof(struct arc_hardware);
+	dev->mtu = choose_mtu();
+
+	dev->addr_len = ARCNET_ALEN;
+	dev->tx_queue_len = 100;
+	dev->broadcast[0] = 0x00;	/* for us, broadcasts are address 0 */
+	dev->watchdog_timeo = TX_TIMEOUT;
+
+	/* New-style flags. */
+	dev->flags = IFF_BROADCAST;
+}
+
+static void arcnet_timer(struct timer_list *t)
+{
+	struct arcnet_local *lp = from_timer(lp, t, timer);
+	struct net_device *dev = lp->dev;
+
+	spin_lock_irq(&lp->lock);
+
+	if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
+		netif_carrier_on(dev);
+		netdev_info(dev, "link up\n");
+	}
+
+	spin_unlock_irq(&lp->lock);
+}
+
+static void reset_device_work(struct work_struct *work)
+{
+	struct arcnet_local *lp;
+	struct net_device *dev;
+
+	lp = container_of(work, struct arcnet_local, reset_work);
+	dev = lp->dev;
+
+	/* Do not bring the network interface back up if an ifdown
+	 * was already done.
+	 */
+	if (!netif_running(dev) || !lp->reset_in_progress)
+		return;
+
+	rtnl_lock();
+
+	/* Do another check, in case of an ifdown that was triggered in
+	 * the small race window between the exit condition above and
+	 * acquiring RTNL.
+	 */
+	if (!netif_running(dev) || !lp->reset_in_progress)
+		goto out;
+
+	dev_close(dev);
+	dev_open(dev, NULL);
+
+out:
+	rtnl_unlock();
+}
+
+static void arcnet_reply_tasklet(struct tasklet_struct *t)
+{
+	struct arcnet_local *lp = from_tasklet(lp, t, reply_tasklet);
+
+	struct sk_buff *ackskb, *skb;
+	struct sock_exterr_skb *serr;
+	struct sock *sk;
+	int ret;
+
+	local_irq_disable();
+	skb = lp->outgoing.skb;
+	if (!skb || !skb->sk) {
+		local_irq_enable();
+		return;
+	}
+
+	sock_hold(skb->sk);
+	sk = skb->sk;
+	ackskb = skb_clone_sk(skb);
+	sock_put(skb->sk);
+
+	if (!ackskb) {
+		local_irq_enable();
+		return;
+	}
+
+	serr = SKB_EXT_ERR(ackskb);
+	memset(serr, 0, sizeof(*serr));
+	serr->ee.ee_errno = ENOMSG;
+	serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
+	serr->ee.ee_data = skb_shinfo(skb)->tskey;
+	serr->ee.ee_info = lp->reply_status;
+
+	/* finally erasing outgoing skb */
+	dev_kfree_skb(lp->outgoing.skb);
+	lp->outgoing.skb = NULL;
+
+	ackskb->dev = lp->dev;
+
+	ret = sock_queue_err_skb(sk, ackskb);
+	if (ret)
+		kfree_skb(ackskb);
+
+	local_irq_enable();
+};
+
+struct net_device *alloc_arcdev(const char *name)
+{
+	struct net_device *dev;
+
+	dev = alloc_netdev(sizeof(struct arcnet_local),
+			   name && *name ? name : "arc%d", NET_NAME_UNKNOWN,
+			   arcdev_setup);
+	if (dev) {
+		struct arcnet_local *lp = netdev_priv(dev);
+
+		lp->dev = dev;
+		spin_lock_init(&lp->lock);
+		timer_setup(&lp->timer, arcnet_timer, 0);
+		INIT_WORK(&lp->reset_work, reset_device_work);
+	}
+
+	return dev;
+}
+EXPORT_SYMBOL(alloc_arcdev);
+
+void free_arcdev(struct net_device *dev)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+
+	/* Do not cancel this at ->ndo_close(), as the workqueue itself
+	 * indirectly calls the ifdown path through dev_close().
+	 */
+	cancel_work_sync(&lp->reset_work);
+	free_netdev(dev);
+}
+EXPORT_SYMBOL(free_arcdev);
+
+/* Open/initialize the board.  This is called sometime after booting when
+ * the 'ifconfig' program is run.
+ *
+ * This routine should set everything up anew at each open, even registers
+ * that "should" only need to be set once at boot, so that there is
+ * non-reboot way to recover if something goes wrong.
+ */
+int arcnet_open(struct net_device *dev)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+	int count, newmtu, error;
+
+	arc_printk(D_INIT, dev, "opened.");
+
+	if (!try_module_get(lp->hw.owner))
+		return -ENODEV;
+
+	if (BUGLVL(D_PROTO)) {
+		arc_printk(D_PROTO, dev, "protocol map (default is '%c'): ",
+			   arc_proto_default->suffix);
+		for (count = 0; count < 256; count++)
+			arc_cont(D_PROTO, "%c", arc_proto_map[count]->suffix);
+		arc_cont(D_PROTO, "\n");
+	}
+
+	tasklet_setup(&lp->reply_tasklet, arcnet_reply_tasklet);
+
+	arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
+
+	/* try to put the card in a defined state - if it fails the first
+	 * time, actually reset it.
+	 */
+	error = -ENODEV;
+	if (lp->hw.reset(dev, 0) && lp->hw.reset(dev, 1))
+		goto out_module_put;
+
+	newmtu = choose_mtu();
+	if (newmtu < dev->mtu)
+		dev->mtu = newmtu;
+
+	arc_printk(D_INIT, dev, "arcnet_open: mtu: %d.\n", dev->mtu);
+
+	/* autodetect the encapsulation for each host. */
+	memset(lp->default_proto, 0, sizeof(lp->default_proto));
+
+	/* the broadcast address is special - use the 'bcast' protocol */
+	for (count = 0; count < 256; count++) {
+		if (arc_proto_map[count] == arc_bcast_proto) {
+			lp->default_proto[0] = count;
+			break;
+		}
+	}
+
+	/* initialize buffers */
+	atomic_set(&lp->buf_lock, 1);
+
+	lp->next_buf = lp->first_free_buf = 0;
+	release_arcbuf(dev, 0);
+	release_arcbuf(dev, 1);
+	release_arcbuf(dev, 2);
+	release_arcbuf(dev, 3);
+	lp->cur_tx = lp->next_tx = -1;
+	lp->cur_rx = -1;
+
+	lp->rfc1201.sequence = 1;
+
+	/* bring up the hardware driver */
+	if (lp->hw.open)
+		lp->hw.open(dev);
+
+	if (dev->dev_addr[0] == 0)
+		arc_printk(D_NORMAL, dev, "WARNING!  Station address 00 is reserved for broadcasts!\n");
+	else if (dev->dev_addr[0] == 255)
+		arc_printk(D_NORMAL, dev, "WARNING!  Station address FF may confuse DOS networking programs!\n");
+
+	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
+	if (lp->hw.status(dev) & RESETflag) {
+		arc_printk(D_DEBUG, dev, "%s: %d: %s\n",
+			   __FILE__, __LINE__, __func__);
+		lp->hw.command(dev, CFLAGScmd | RESETclear);
+	}
+
+	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
+	/* make sure we're ready to receive IRQ's. */
+	lp->hw.intmask(dev, 0);
+	udelay(1);		/* give it time to set the mask before
+				 * we reset it again. (may not even be
+				 * necessary)
+				 */
+	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
+	lp->intmask = NORXflag | RECONflag;
+	lp->hw.intmask(dev, lp->intmask);
+	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
+
+	netif_carrier_off(dev);
+	netif_start_queue(dev);
+	mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
+
+	arcnet_led_event(dev, ARCNET_LED_EVENT_OPEN);
+	return 0;
+
+ out_module_put:
+	module_put(lp->hw.owner);
+	return error;
+}
+EXPORT_SYMBOL(arcnet_open);
+
+/* The inverse routine to arcnet_open - shuts down the card. */
+int arcnet_close(struct net_device *dev)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+
+	arcnet_led_event(dev, ARCNET_LED_EVENT_STOP);
+	del_timer_sync(&lp->timer);
+
+	netif_stop_queue(dev);
+	netif_carrier_off(dev);
+
+	tasklet_kill(&lp->reply_tasklet);
+
+	/* flush TX and disable RX */
+	lp->hw.intmask(dev, 0);
+	lp->hw.command(dev, NOTXcmd);	/* stop transmit */
+	lp->hw.command(dev, NORXcmd);	/* disable receive */
+	mdelay(1);
+
+	/* shut down the card */
+	lp->hw.close(dev);
+
+	/* reset counters */
+	lp->reset_in_progress = 0;
+
+	module_put(lp->hw.owner);
+	return 0;
+}
+EXPORT_SYMBOL(arcnet_close);
+
+static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
+			 unsigned short type, const void *daddr,
+			 const void *saddr, unsigned len)
+{
+	const struct arcnet_local *lp = netdev_priv(dev);
+	uint8_t _daddr, proto_num;
+	struct ArcProto *proto;
+
+	arc_printk(D_DURING, dev,
+		   "create header from %d to %d; protocol %d (%Xh); size %u.\n",
+		   saddr ? *(uint8_t *)saddr : -1,
+		   daddr ? *(uint8_t *)daddr : -1,
+		   type, type, len);
+
+	if (skb->len != 0 && len != skb->len)
+		arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  skb->len(%d) != len(%d)!\n",
+			   skb->len, len);
+
+	/* Type is host order - ? */
+	if (type == ETH_P_ARCNET) {
+		proto = arc_raw_proto;
+		arc_printk(D_DEBUG, dev, "arc_raw_proto used. proto='%c'\n",
+			   proto->suffix);
+		_daddr = daddr ? *(uint8_t *)daddr : 0;
+	} else if (!daddr) {
+		/* if the dest addr isn't provided, we can't choose an
+		 * encapsulation!  Store the packet type (eg. ETH_P_IP)
+		 * for now, and we'll push on a real header when we do
+		 * rebuild_header.
+		 */
+		*(uint16_t *)skb_push(skb, 2) = type;
+		/* XXX: Why not use skb->mac_len? */
+		if (skb->network_header - skb->mac_header != 2)
+			arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  diff (%u) is not 2!\n",
+				   skb->network_header - skb->mac_header);
+		return -2;	/* return error -- can't transmit yet! */
+	} else {
+		/* otherwise, we can just add the header as usual. */
+		_daddr = *(uint8_t *)daddr;
+		proto_num = lp->default_proto[_daddr];
+		proto = arc_proto_map[proto_num];
+		arc_printk(D_DURING, dev, "building header for %02Xh using protocol '%c'\n",
+			   proto_num, proto->suffix);
+		if (proto == &arc_proto_null && arc_bcast_proto != proto) {
+			arc_printk(D_DURING, dev, "actually, let's use '%c' instead.\n",
+				   arc_bcast_proto->suffix);
+			proto = arc_bcast_proto;
+		}
+	}
+	return proto->build_header(skb, dev, type, _daddr);
+}
+
+/* Called by the kernel in order to transmit a packet. */
+netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
+			       struct net_device *dev)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+	struct archdr *pkt;
+	struct arc_rfc1201 *soft;
+	struct ArcProto *proto;
+	int txbuf;
+	unsigned long flags;
+	int retval;
+
+	arc_printk(D_DURING, dev,
+		   "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
+		   lp->hw.status(dev), lp->cur_tx, lp->next_tx, skb->len, skb->protocol);
+
+	pkt = (struct archdr *)skb->data;
+	soft = &pkt->soft.rfc1201;
+	proto = arc_proto_map[soft->proto];
+
+	arc_printk(D_SKB_SIZE, dev, "skb: transmitting %d bytes to %02X\n",
+		   skb->len, pkt->hard.dest);
+	if (BUGLVL(D_SKB))
+		arcnet_dump_skb(dev, skb, "tx");
+
+	/* fits in one packet? */
+	if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
+		arc_printk(D_NORMAL, dev, "fixme: packet too large: compensating badly!\n");
+		dev_kfree_skb(skb);
+		return NETDEV_TX_OK;	/* don't try again */
+	}
+
+	/* We're busy transmitting a packet... */
+	netif_stop_queue(dev);
+
+	spin_lock_irqsave(&lp->lock, flags);
+	lp->hw.intmask(dev, 0);
+	if (lp->next_tx == -1)
+		txbuf = get_arcbuf(dev);
+	else
+		txbuf = -1;
+
+	if (txbuf != -1) {
+		lp->outgoing.skb = skb;
+		if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
+		    !proto->ack_tx) {
+			/* done right away and we don't want to acknowledge
+			 *  the package later - forget about it now
+			 */
+			dev->stats.tx_bytes += skb->len;
+		} else {
+			/* do it the 'split' way */
+			lp->outgoing.proto = proto;
+			lp->outgoing.skb = skb;
+			lp->outgoing.pkt = pkt;
+
+			if (proto->continue_tx &&
+			    proto->continue_tx(dev, txbuf)) {
+				arc_printk(D_NORMAL, dev,
+					   "bug! continue_tx finished the first time! (proto='%c')\n",
+					   proto->suffix);
+			}
+		}
+		retval = NETDEV_TX_OK;
+		lp->next_tx = txbuf;
+	} else {
+		retval = NETDEV_TX_BUSY;
+	}
+
+	arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
+		   __FILE__, __LINE__, __func__, lp->hw.status(dev));
+	/* make sure we didn't ignore a TX IRQ while we were in here */
+	lp->hw.intmask(dev, 0);
+
+	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
+	lp->intmask |= TXFREEflag | EXCNAKflag;
+	lp->hw.intmask(dev, lp->intmask);
+	arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
+		   __FILE__, __LINE__, __func__, lp->hw.status(dev));
+
+	arcnet_led_event(dev, ARCNET_LED_EVENT_TX);
+
+	spin_unlock_irqrestore(&lp->lock, flags);
+	return retval;		/* no need to try again */
+}
+EXPORT_SYMBOL(arcnet_send_packet);
+
+/* Actually start transmitting a packet that was loaded into a buffer
+ * by prepare_tx.  This should _only_ be called by the interrupt handler.
+ */
+static int go_tx(struct net_device *dev)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+
+	arc_printk(D_DURING, dev, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
+		   lp->hw.status(dev), lp->intmask, lp->next_tx, lp->cur_tx);
+
+	if (lp->cur_tx != -1 || lp->next_tx == -1)
+		return 0;
+
+	if (BUGLVL(D_TX))
+		arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
+
+	lp->cur_tx = lp->next_tx;
+	lp->next_tx = -1;
+
+	/* start sending */
+	lp->hw.command(dev, TXcmd | (lp->cur_tx << 3));
+
+	dev->stats.tx_packets++;
+	lp->lasttrans_dest = lp->lastload_dest;
+	lp->lastload_dest = 0;
+	lp->excnak_pending = 0;
+	lp->intmask |= TXFREEflag | EXCNAKflag;
+
+	return 1;
+}
+
+/* Called by the kernel when transmit times out */
+void arcnet_timeout(struct net_device *dev, unsigned int txqueue)
+{
+	unsigned long flags;
+	struct arcnet_local *lp = netdev_priv(dev);
+	int status = lp->hw.status(dev);
+	char *msg;
+
+	spin_lock_irqsave(&lp->lock, flags);
+	if (status & TXFREEflag) {	/* transmit _DID_ finish */
+		msg = " - missed IRQ?";
+	} else {
+		msg = "";
+		dev->stats.tx_aborted_errors++;
+		lp->timed_out = 1;
+		lp->hw.command(dev, NOTXcmd | (lp->cur_tx << 3));
+	}
+	dev->stats.tx_errors++;
+
+	/* make sure we didn't miss a TX or a EXC NAK IRQ */
+	lp->hw.intmask(dev, 0);
+	lp->intmask |= TXFREEflag | EXCNAKflag;
+	lp->hw.intmask(dev, lp->intmask);
+
+	spin_unlock_irqrestore(&lp->lock, flags);
+
+	if (time_after(jiffies, lp->last_timeout + 10 * HZ)) {
+		arc_printk(D_EXTRA, dev, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
+			   msg, status, lp->intmask, lp->lasttrans_dest);
+		lp->last_timeout = jiffies;
+	}
+
+	if (lp->cur_tx == -1)
+		netif_wake_queue(dev);
+}
+EXPORT_SYMBOL(arcnet_timeout);
+
+/* The typical workload of the driver: Handle the network interface
+ * interrupts. Establish which device needs attention, and call the correct
+ * chipset interrupt handler.
+ */
+irqreturn_t arcnet_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = dev_id;
+	struct arcnet_local *lp;
+	int recbuf, status, diagstatus, didsomething, boguscount;
+	unsigned long flags;
+	int retval = IRQ_NONE;
+
+	arc_printk(D_DURING, dev, "\n");
+
+	arc_printk(D_DURING, dev, "in arcnet_interrupt\n");
+
+	lp = netdev_priv(dev);
+	BUG_ON(!lp);
+
+	spin_lock_irqsave(&lp->lock, flags);
+
+	if (lp->reset_in_progress)
+		goto out;
+
+	/* RESET flag was enabled - if device is not running, we must
+	 * clear it right away (but nothing else).
+	 */
+	if (!netif_running(dev)) {
+		if (lp->hw.status(dev) & RESETflag)
+			lp->hw.command(dev, CFLAGScmd | RESETclear);
+		lp->hw.intmask(dev, 0);
+		spin_unlock_irqrestore(&lp->lock, flags);
+		return retval;
+	}
+
+	arc_printk(D_DURING, dev, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
+		   lp->hw.status(dev), lp->intmask);
+
+	boguscount = 5;
+	do {
+		status = lp->hw.status(dev);
+		diagstatus = (status >> 8) & 0xFF;
+
+		arc_printk(D_DEBUG, dev, "%s: %d: %s: status=%x\n",
+			   __FILE__, __LINE__, __func__, status);
+		didsomething = 0;
+
+		/* RESET flag was enabled - card is resetting and if RX is
+		 * disabled, it's NOT because we just got a packet.
+		 *
+		 * The card is in an undefined state.
+		 * Clear it out and start over.
+		 */
+		if (status & RESETflag) {
+			arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
+				   status);
+
+			lp->reset_in_progress = 1;
+			netif_stop_queue(dev);
+			netif_carrier_off(dev);
+			schedule_work(&lp->reset_work);
+
+			/* get out of the interrupt handler! */
+			goto out;
+		}
+		/* RX is inhibited - we must have received something.
+		 * Prepare to receive into the next buffer.
+		 *
+		 * We don't actually copy the received packet from the card
+		 * until after the transmit handler runs (and possibly
+		 * launches the next tx); this should improve latency slightly
+		 * if we get both types of interrupts at once.
+		 */
+		recbuf = -1;
+		if (status & lp->intmask & NORXflag) {
+			recbuf = lp->cur_rx;
+			arc_printk(D_DURING, dev, "Buffer #%d: receive irq (status=%Xh)\n",
+				   recbuf, status);
+
+			lp->cur_rx = get_arcbuf(dev);
+			if (lp->cur_rx != -1) {
+				arc_printk(D_DURING, dev, "enabling receive to buffer #%d\n",
+					   lp->cur_rx);
+				lp->hw.command(dev, RXcmd | (lp->cur_rx << 3) | RXbcasts);
+			}
+			didsomething++;
+		}
+
+		if ((diagstatus & EXCNAKflag)) {
+			arc_printk(D_DURING, dev, "EXCNAK IRQ (diagstat=%Xh)\n",
+				   diagstatus);
+
+			lp->hw.command(dev, NOTXcmd);      /* disable transmit */
+			lp->excnak_pending = 1;
+
+			lp->hw.command(dev, EXCNAKclear);
+			lp->intmask &= ~(EXCNAKflag);
+			didsomething++;
+		}
+
+		/* a transmit finished, and we're interested in it. */
+		if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
+			int ackstatus;
+			lp->intmask &= ~(TXFREEflag | EXCNAKflag);
+
+			if (status & TXACKflag)
+				ackstatus = 2;
+			else if (lp->excnak_pending)
+				ackstatus = 1;
+			else
+				ackstatus = 0;
+
+			arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
+				   status);
+
+			if (lp->cur_tx != -1 && !lp->timed_out) {
+				if (!(status & TXACKflag)) {
+					if (lp->lasttrans_dest != 0) {
+						arc_printk(D_EXTRA, dev,
+							   "transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
+							   status,
+							   lp->lasttrans_dest);
+						dev->stats.tx_errors++;
+						dev->stats.tx_carrier_errors++;
+					} else {
+						arc_printk(D_DURING, dev,
+							   "broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
+							   status,
+							   lp->lasttrans_dest);
+					}
+				}
+
+				if (lp->outgoing.proto &&
+				    lp->outgoing.proto->ack_tx) {
+					lp->outgoing.proto
+						->ack_tx(dev, ackstatus);
+				}
+				lp->reply_status = ackstatus;
+				tasklet_hi_schedule(&lp->reply_tasklet);
+			}
+			if (lp->cur_tx != -1)
+				release_arcbuf(dev, lp->cur_tx);
+
+			lp->cur_tx = -1;
+			lp->timed_out = 0;
+			didsomething++;
+
+			/* send another packet if there is one */
+			go_tx(dev);
+
+			/* continue a split packet, if any */
+			if (lp->outgoing.proto &&
+			    lp->outgoing.proto->continue_tx) {
+				int txbuf = get_arcbuf(dev);
+
+				if (txbuf != -1) {
+					if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
+						/* that was the last segment */
+						dev->stats.tx_bytes += lp->outgoing.skb->len;
+						if (!lp->outgoing.proto->ack_tx) {
+							dev_kfree_skb_irq(lp->outgoing.skb);
+							lp->outgoing.proto = NULL;
+						}
+					}
+					lp->next_tx = txbuf;
+				}
+			}
+			/* inform upper layers of idleness, if necessary */
+			if (lp->cur_tx == -1)
+				netif_wake_queue(dev);
+		}
+		/* now process the received packet, if any */
+		if (recbuf != -1) {
+			if (BUGLVL(D_RX))
+				arcnet_dump_packet(dev, recbuf, "rx irq", 0);
+
+			arcnet_rx(dev, recbuf);
+			release_arcbuf(dev, recbuf);
+
+			didsomething++;
+		}
+		if (status & lp->intmask & RECONflag) {
+			lp->hw.command(dev, CFLAGScmd | CONFIGclear);
+			dev->stats.tx_carrier_errors++;
+
+			arc_printk(D_RECON, dev, "Network reconfiguration detected (status=%Xh)\n",
+				   status);
+			if (netif_carrier_ok(dev)) {
+				netif_carrier_off(dev);
+				netdev_info(dev, "link down\n");
+			}
+			mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
+
+			arcnet_led_event(dev, ARCNET_LED_EVENT_RECON);
+			/* MYRECON bit is at bit 7 of diagstatus */
+			if (diagstatus & 0x80)
+				arc_printk(D_RECON, dev, "Put out that recon myself\n");
+
+			/* is the RECON info empty or old? */
+			if (!lp->first_recon || !lp->last_recon ||
+			    time_after(jiffies, lp->last_recon + HZ * 10)) {
+				if (lp->network_down)
+					arc_printk(D_NORMAL, dev, "reconfiguration detected: cabling restored?\n");
+				lp->first_recon = lp->last_recon = jiffies;
+				lp->num_recons = lp->network_down = 0;
+
+				arc_printk(D_DURING, dev, "recon: clearing counters.\n");
+			} else {	/* add to current RECON counter */
+				lp->last_recon = jiffies;
+				lp->num_recons++;
+
+				arc_printk(D_DURING, dev, "recon: counter=%d, time=%lds, net=%d\n",
+					   lp->num_recons,
+					   (lp->last_recon - lp->first_recon) / HZ,
+					   lp->network_down);
+
+				/* if network is marked up;
+				 * and first_recon and last_recon are 60+ apart;
+				 * and the average no. of recons counted is
+				 *    > RECON_THRESHOLD/min;
+				 * then print a warning message.
+				 */
+				if (!lp->network_down &&
+				    (lp->last_recon - lp->first_recon) <= HZ * 60 &&
+				    lp->num_recons >= RECON_THRESHOLD) {
+					lp->network_down = 1;
+					arc_printk(D_NORMAL, dev, "many reconfigurations detected: cabling problem?\n");
+				} else if (!lp->network_down &&
+					   lp->last_recon - lp->first_recon > HZ * 60) {
+					/* reset counters if we've gone for
+					 *  over a minute.
+					 */
+					lp->first_recon = lp->last_recon;
+					lp->num_recons = 1;
+				}
+			}
+		} else if (lp->network_down &&
+			   time_after(jiffies, lp->last_recon + HZ * 10)) {
+			if (lp->network_down)
+				arc_printk(D_NORMAL, dev, "cabling restored?\n");
+			lp->first_recon = lp->last_recon = 0;
+			lp->num_recons = lp->network_down = 0;
+
+			arc_printk(D_DURING, dev, "not recon: clearing counters anyway.\n");
+			netif_carrier_on(dev);
+		}
+
+		if (didsomething)
+			retval |= IRQ_HANDLED;
+	} while (--boguscount && didsomething);
+
+	arc_printk(D_DURING, dev, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
+		   lp->hw.status(dev), boguscount);
+	arc_printk(D_DURING, dev, "\n");
+
+	lp->hw.intmask(dev, 0);
+	udelay(1);
+	lp->hw.intmask(dev, lp->intmask);
+
+out:
+	spin_unlock_irqrestore(&lp->lock, flags);
+	return retval;
+}
+EXPORT_SYMBOL(arcnet_interrupt);
+
+/* This is a generic packet receiver that calls arcnet??_rx depending on the
+ * protocol ID found.
+ */
+static void arcnet_rx(struct net_device *dev, int bufnum)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+	union {
+		struct archdr pkt;
+		char buf[512];
+	} rxdata;
+	struct arc_rfc1201 *soft;
+	int length, ofs;
+
+	soft = &rxdata.pkt.soft.rfc1201;
+
+	lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);
+	if (rxdata.pkt.hard.offset[0]) {
+		ofs = rxdata.pkt.hard.offset[0];
+		length = 256 - ofs;
+	} else {
+		ofs = rxdata.pkt.hard.offset[1];
+		length = 512 - ofs;
+	}
+
+	/* get the full header, if possible */
+	if (sizeof(rxdata.pkt.soft) <= length) {
+		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));
+	} else {
+		memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));
+		lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
+	}
+
+	arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
+		   bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);
+
+	dev->stats.rx_packets++;
+	dev->stats.rx_bytes += length + ARC_HDR_SIZE;
+
+	/* call the right receiver for the protocol */
+	if (arc_proto_map[soft->proto]->is_ip) {
+		if (BUGLVL(D_PROTO)) {
+			struct ArcProto
+			*oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],
+			*newp = arc_proto_map[soft->proto];
+
+			if (oldp != newp) {
+				arc_printk(D_PROTO, dev,
+					   "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
+					   soft->proto, rxdata.pkt.hard.source,
+					   newp->suffix, oldp->suffix);
+			}
+		}
+
+		/* broadcasts will always be done with the last-used encap. */
+		lp->default_proto[0] = soft->proto;
+
+		/* in striking contrast, the following isn't a hack. */
+		lp->default_proto[rxdata.pkt.hard.source] = soft->proto;
+	}
+	/* call the protocol-specific receiver. */
+	arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);
+}
+
+static void null_rx(struct net_device *dev, int bufnum,
+		    struct archdr *pkthdr, int length)
+{
+	arc_printk(D_PROTO, dev,
+		   "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
+		   pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
+}
+
+static int null_build_header(struct sk_buff *skb, struct net_device *dev,
+			     unsigned short type, uint8_t daddr)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+
+	arc_printk(D_PROTO, dev,
+		   "tx: can't build header for encap %02Xh; load a protocol driver.\n",
+		   lp->default_proto[daddr]);
+
+	/* always fails */
+	return 0;
+}
+
+/* the "do nothing" prepare_tx function warns that there's nothing to do. */
+static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
+			   int length, int bufnum)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+	struct arc_hardware newpkt;
+
+	arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
+
+	/* send a packet to myself -- will never get received, of course */
+	newpkt.source = newpkt.dest = dev->dev_addr[0];
+
+	/* only one byte of actual data (and it's random) */
+	newpkt.offset[0] = 0xFF;
+
+	lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
+
+	return 1;		/* done */
+}