if_vtnet.c revision 285016
1/*-
2 * Copyright (c) 2011, Bryan Venteicher <bryanv@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice unmodified, this list of conditions, and the following
10 *    disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27/* Driver for VirtIO network devices. */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: stable/10/sys/dev/virtio/network/if_vtnet.c 285016 2015-07-01 21:21:14Z kp $");
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/kernel.h>
35#include <sys/sockio.h>
36#include <sys/mbuf.h>
37#include <sys/malloc.h>
38#include <sys/module.h>
39#include <sys/socket.h>
40#include <sys/sysctl.h>
41#include <sys/random.h>
42#include <sys/sglist.h>
43#include <sys/lock.h>
44#include <sys/mutex.h>
45#include <sys/taskqueue.h>
46#include <sys/smp.h>
47#include <machine/smp.h>
48
49#include <vm/uma.h>
50
51#include <net/ethernet.h>
52#include <net/if.h>
53#include <net/if_arp.h>
54#include <net/if_dl.h>
55#include <net/if_types.h>
56#include <net/if_media.h>
57#include <net/if_vlan_var.h>
58
59#include <net/bpf.h>
60
61#include <netinet/in_systm.h>
62#include <netinet/in.h>
63#include <netinet/ip.h>
64#include <netinet/ip6.h>
65#include <netinet6/ip6_var.h>
66#include <netinet/udp.h>
67#include <netinet/tcp.h>
68#include <netinet/sctp.h>
69
70#include <machine/bus.h>
71#include <machine/resource.h>
72#include <sys/bus.h>
73#include <sys/rman.h>
74
75#include <dev/virtio/virtio.h>
76#include <dev/virtio/virtqueue.h>
77#include <dev/virtio/network/virtio_net.h>
78#include <dev/virtio/network/if_vtnetvar.h>
79
80#include "virtio_if.h"
81
82#include "opt_inet.h"
83#include "opt_inet6.h"
84
85static int	vtnet_modevent(module_t, int, void *);
86
87static int	vtnet_probe(device_t);
88static int	vtnet_attach(device_t);
89static int	vtnet_detach(device_t);
90static int	vtnet_suspend(device_t);
91static int	vtnet_resume(device_t);
92static int	vtnet_shutdown(device_t);
93static int	vtnet_attach_completed(device_t);
94static int	vtnet_config_change(device_t);
95
96static void	vtnet_negotiate_features(struct vtnet_softc *);
97static void	vtnet_setup_features(struct vtnet_softc *);
98static int	vtnet_init_rxq(struct vtnet_softc *, int);
99static int	vtnet_init_txq(struct vtnet_softc *, int);
100static int	vtnet_alloc_rxtx_queues(struct vtnet_softc *);
101static void	vtnet_free_rxtx_queues(struct vtnet_softc *);
102static int	vtnet_alloc_rx_filters(struct vtnet_softc *);
103static void	vtnet_free_rx_filters(struct vtnet_softc *);
104static int	vtnet_alloc_virtqueues(struct vtnet_softc *);
105static int	vtnet_setup_interface(struct vtnet_softc *);
106static int	vtnet_change_mtu(struct vtnet_softc *, int);
107static int	vtnet_ioctl(struct ifnet *, u_long, caddr_t);
108
109static int	vtnet_rxq_populate(struct vtnet_rxq *);
110static void	vtnet_rxq_free_mbufs(struct vtnet_rxq *);
111static struct mbuf *
112		vtnet_rx_alloc_buf(struct vtnet_softc *, int , struct mbuf **);
113static int	vtnet_rxq_replace_lro_nomgr_buf(struct vtnet_rxq *,
114		    struct mbuf *, int);
115static int	vtnet_rxq_replace_buf(struct vtnet_rxq *, struct mbuf *, int);
116static int	vtnet_rxq_enqueue_buf(struct vtnet_rxq *, struct mbuf *);
117static int	vtnet_rxq_new_buf(struct vtnet_rxq *);
118static int	vtnet_rxq_csum(struct vtnet_rxq *, struct mbuf *,
119		     struct virtio_net_hdr *);
120static void	vtnet_rxq_discard_merged_bufs(struct vtnet_rxq *, int);
121static void	vtnet_rxq_discard_buf(struct vtnet_rxq *, struct mbuf *);
122static int	vtnet_rxq_merged_eof(struct vtnet_rxq *, struct mbuf *, int);
123static void	vtnet_rxq_input(struct vtnet_rxq *, struct mbuf *,
124		    struct virtio_net_hdr *);
125static int	vtnet_rxq_eof(struct vtnet_rxq *);
126static void	vtnet_rx_vq_intr(void *);
127static void	vtnet_rxq_tq_intr(void *, int);
128
129static int	vtnet_txq_below_threshold(struct vtnet_txq *);
130static int	vtnet_txq_notify(struct vtnet_txq *);
131static void	vtnet_txq_free_mbufs(struct vtnet_txq *);
132static int	vtnet_txq_offload_ctx(struct vtnet_txq *, struct mbuf *,
133		    int *, int *, int *);
134static int	vtnet_txq_offload_tso(struct vtnet_txq *, struct mbuf *, int,
135		    int, struct virtio_net_hdr *);
136static struct mbuf *
137		vtnet_txq_offload(struct vtnet_txq *, struct mbuf *,
138		    struct virtio_net_hdr *);
139static int	vtnet_txq_enqueue_buf(struct vtnet_txq *, struct mbuf **,
140		    struct vtnet_tx_header *);
141static int	vtnet_txq_encap(struct vtnet_txq *, struct mbuf **);
142#ifdef VTNET_LEGACY_TX
143static void	vtnet_start_locked(struct vtnet_txq *, struct ifnet *);
144static void	vtnet_start(struct ifnet *);
145#else
146static int	vtnet_txq_mq_start_locked(struct vtnet_txq *, struct mbuf *);
147static int	vtnet_txq_mq_start(struct ifnet *, struct mbuf *);
148static void	vtnet_txq_tq_deferred(void *, int);
149#endif
150static void	vtnet_txq_start(struct vtnet_txq *);
151static void	vtnet_txq_tq_intr(void *, int);
152static int	vtnet_txq_eof(struct vtnet_txq *);
153static void	vtnet_tx_vq_intr(void *);
154static void	vtnet_tx_start_all(struct vtnet_softc *);
155
156#ifndef VTNET_LEGACY_TX
157static void	vtnet_qflush(struct ifnet *);
158#endif
159
160static int	vtnet_watchdog(struct vtnet_txq *);
161static void	vtnet_rxq_accum_stats(struct vtnet_rxq *,
162		    struct vtnet_rxq_stats *);
163static void	vtnet_txq_accum_stats(struct vtnet_txq *,
164		    struct vtnet_txq_stats *);
165static void	vtnet_accumulate_stats(struct vtnet_softc *);
166static void	vtnet_tick(void *);
167
168static void	vtnet_start_taskqueues(struct vtnet_softc *);
169static void	vtnet_free_taskqueues(struct vtnet_softc *);
170static void	vtnet_drain_taskqueues(struct vtnet_softc *);
171
172static void	vtnet_drain_rxtx_queues(struct vtnet_softc *);
173static void	vtnet_stop_rendezvous(struct vtnet_softc *);
174static void	vtnet_stop(struct vtnet_softc *);
175static int	vtnet_virtio_reinit(struct vtnet_softc *);
176static void	vtnet_init_rx_filters(struct vtnet_softc *);
177static int	vtnet_init_rx_queues(struct vtnet_softc *);
178static int	vtnet_init_tx_queues(struct vtnet_softc *);
179static int	vtnet_init_rxtx_queues(struct vtnet_softc *);
180static void	vtnet_set_active_vq_pairs(struct vtnet_softc *);
181static int	vtnet_reinit(struct vtnet_softc *);
182static void	vtnet_init_locked(struct vtnet_softc *);
183static void	vtnet_init(void *);
184
185static void	vtnet_free_ctrl_vq(struct vtnet_softc *);
186static void	vtnet_exec_ctrl_cmd(struct vtnet_softc *, void *,
187		    struct sglist *, int, int);
188static int	vtnet_ctrl_mac_cmd(struct vtnet_softc *, uint8_t *);
189static int	vtnet_ctrl_mq_cmd(struct vtnet_softc *, uint16_t);
190static int	vtnet_ctrl_rx_cmd(struct vtnet_softc *, int, int);
191static int	vtnet_set_promisc(struct vtnet_softc *, int);
192static int	vtnet_set_allmulti(struct vtnet_softc *, int);
193static void	vtnet_attach_disable_promisc(struct vtnet_softc *);
194static void	vtnet_rx_filter(struct vtnet_softc *);
195static void	vtnet_rx_filter_mac(struct vtnet_softc *);
196static int	vtnet_exec_vlan_filter(struct vtnet_softc *, int, uint16_t);
197static void	vtnet_rx_filter_vlan(struct vtnet_softc *);
198static void	vtnet_update_vlan_filter(struct vtnet_softc *, int, uint16_t);
199static void	vtnet_register_vlan(void *, struct ifnet *, uint16_t);
200static void	vtnet_unregister_vlan(void *, struct ifnet *, uint16_t);
201
202static int	vtnet_is_link_up(struct vtnet_softc *);
203static void	vtnet_update_link_status(struct vtnet_softc *);
204static int	vtnet_ifmedia_upd(struct ifnet *);
205static void	vtnet_ifmedia_sts(struct ifnet *, struct ifmediareq *);
206static void	vtnet_get_hwaddr(struct vtnet_softc *);
207static void	vtnet_set_hwaddr(struct vtnet_softc *);
208static void	vtnet_vlan_tag_remove(struct mbuf *);
209static void	vtnet_set_rx_process_limit(struct vtnet_softc *);
210static void	vtnet_set_tx_intr_threshold(struct vtnet_softc *);
211
212static void	vtnet_setup_rxq_sysctl(struct sysctl_ctx_list *,
213		    struct sysctl_oid_list *, struct vtnet_rxq *);
214static void	vtnet_setup_txq_sysctl(struct sysctl_ctx_list *,
215		    struct sysctl_oid_list *, struct vtnet_txq *);
216static void	vtnet_setup_queue_sysctl(struct vtnet_softc *);
217static void	vtnet_setup_sysctl(struct vtnet_softc *);
218
219static int	vtnet_rxq_enable_intr(struct vtnet_rxq *);
220static void	vtnet_rxq_disable_intr(struct vtnet_rxq *);
221static int	vtnet_txq_enable_intr(struct vtnet_txq *);
222static void	vtnet_txq_disable_intr(struct vtnet_txq *);
223static void	vtnet_enable_rx_interrupts(struct vtnet_softc *);
224static void	vtnet_enable_tx_interrupts(struct vtnet_softc *);
225static void	vtnet_enable_interrupts(struct vtnet_softc *);
226static void	vtnet_disable_rx_interrupts(struct vtnet_softc *);
227static void	vtnet_disable_tx_interrupts(struct vtnet_softc *);
228static void	vtnet_disable_interrupts(struct vtnet_softc *);
229
230static int	vtnet_tunable_int(struct vtnet_softc *, const char *, int);
231
232/* Tunables. */
233static int vtnet_csum_disable = 0;
234TUNABLE_INT("hw.vtnet.csum_disable", &vtnet_csum_disable);
235static int vtnet_tso_disable = 0;
236TUNABLE_INT("hw.vtnet.tso_disable", &vtnet_tso_disable);
237static int vtnet_lro_disable = 0;
238TUNABLE_INT("hw.vtnet.lro_disable", &vtnet_lro_disable);
239static int vtnet_mq_disable = 0;
240TUNABLE_INT("hw.vtnet.mq_disable", &vtnet_mq_disable);
241static int vtnet_mq_max_pairs = 0;
242TUNABLE_INT("hw.vtnet.mq_max_pairs", &vtnet_mq_max_pairs);
243static int vtnet_rx_process_limit = 512;
244TUNABLE_INT("hw.vtnet.rx_process_limit", &vtnet_rx_process_limit);
245
246static uma_zone_t vtnet_tx_header_zone;
247
248static struct virtio_feature_desc vtnet_feature_desc[] = {
249	{ VIRTIO_NET_F_CSUM,		"TxChecksum"	},
250	{ VIRTIO_NET_F_GUEST_CSUM,	"RxChecksum"	},
251	{ VIRTIO_NET_F_MAC,		"MacAddress"	},
252	{ VIRTIO_NET_F_GSO,		"TxAllGSO"	},
253	{ VIRTIO_NET_F_GUEST_TSO4,	"RxTSOv4"	},
254	{ VIRTIO_NET_F_GUEST_TSO6,	"RxTSOv6"	},
255	{ VIRTIO_NET_F_GUEST_ECN,	"RxECN"		},
256	{ VIRTIO_NET_F_GUEST_UFO,	"RxUFO"		},
257	{ VIRTIO_NET_F_HOST_TSO4,	"TxTSOv4"	},
258	{ VIRTIO_NET_F_HOST_TSO6,	"TxTSOv6"	},
259	{ VIRTIO_NET_F_HOST_ECN,	"TxTSOECN"	},
260	{ VIRTIO_NET_F_HOST_UFO,	"TxUFO"		},
261	{ VIRTIO_NET_F_MRG_RXBUF,	"MrgRxBuf"	},
262	{ VIRTIO_NET_F_STATUS,		"Status"	},
263	{ VIRTIO_NET_F_CTRL_VQ,		"ControlVq"	},
264	{ VIRTIO_NET_F_CTRL_RX,		"RxMode"	},
265	{ VIRTIO_NET_F_CTRL_VLAN,	"VLanFilter"	},
266	{ VIRTIO_NET_F_CTRL_RX_EXTRA,	"RxModeExtra"	},
267	{ VIRTIO_NET_F_GUEST_ANNOUNCE,	"GuestAnnounce"	},
268	{ VIRTIO_NET_F_MQ,		"Multiqueue"	},
269	{ VIRTIO_NET_F_CTRL_MAC_ADDR,	"SetMacAddress"	},
270
271	{ 0, NULL }
272};
273
274static device_method_t vtnet_methods[] = {
275	/* Device methods. */
276	DEVMETHOD(device_probe,			vtnet_probe),
277	DEVMETHOD(device_attach,		vtnet_attach),
278	DEVMETHOD(device_detach,		vtnet_detach),
279	DEVMETHOD(device_suspend,		vtnet_suspend),
280	DEVMETHOD(device_resume,		vtnet_resume),
281	DEVMETHOD(device_shutdown,		vtnet_shutdown),
282
283	/* VirtIO methods. */
284	DEVMETHOD(virtio_attach_completed,	vtnet_attach_completed),
285	DEVMETHOD(virtio_config_change,		vtnet_config_change),
286
287	DEVMETHOD_END
288};
289
290#ifdef DEV_NETMAP
291#include <dev/netmap/if_vtnet_netmap.h>
292#endif /* DEV_NETMAP */
293
294static driver_t vtnet_driver = {
295	"vtnet",
296	vtnet_methods,
297	sizeof(struct vtnet_softc)
298};
299static devclass_t vtnet_devclass;
300
301DRIVER_MODULE(vtnet, virtio_pci, vtnet_driver, vtnet_devclass,
302    vtnet_modevent, 0);
303MODULE_VERSION(vtnet, 1);
304MODULE_DEPEND(vtnet, virtio, 1, 1, 1);
305
306static int
307vtnet_modevent(module_t mod, int type, void *unused)
308{
309	int error;
310
311	error = 0;
312
313	switch (type) {
314	case MOD_LOAD:
315		vtnet_tx_header_zone = uma_zcreate("vtnet_tx_hdr",
316		    sizeof(struct vtnet_tx_header),
317		    NULL, NULL, NULL, NULL, 0, 0);
318		break;
319	case MOD_QUIESCE:
320	case MOD_UNLOAD:
321		if (uma_zone_get_cur(vtnet_tx_header_zone) > 0)
322			error = EBUSY;
323		else if (type == MOD_UNLOAD) {
324			uma_zdestroy(vtnet_tx_header_zone);
325			vtnet_tx_header_zone = NULL;
326		}
327		break;
328	case MOD_SHUTDOWN:
329		break;
330	default:
331		error = EOPNOTSUPP;
332		break;
333	}
334
335	return (error);
336}
337
338static int
339vtnet_probe(device_t dev)
340{
341
342	if (virtio_get_device_type(dev) != VIRTIO_ID_NETWORK)
343		return (ENXIO);
344
345	device_set_desc(dev, "VirtIO Networking Adapter");
346
347	return (BUS_PROBE_DEFAULT);
348}
349
350static int
351vtnet_attach(device_t dev)
352{
353	struct vtnet_softc *sc;
354	int error;
355
356	sc = device_get_softc(dev);
357	sc->vtnet_dev = dev;
358
359	/* Register our feature descriptions. */
360	virtio_set_feature_desc(dev, vtnet_feature_desc);
361
362	VTNET_CORE_LOCK_INIT(sc);
363	callout_init_mtx(&sc->vtnet_tick_ch, VTNET_CORE_MTX(sc), 0);
364
365	vtnet_setup_sysctl(sc);
366	vtnet_setup_features(sc);
367
368	error = vtnet_alloc_rx_filters(sc);
369	if (error) {
370		device_printf(dev, "cannot allocate Rx filters\n");
371		goto fail;
372	}
373
374	error = vtnet_alloc_rxtx_queues(sc);
375	if (error) {
376		device_printf(dev, "cannot allocate queues\n");
377		goto fail;
378	}
379
380	error = vtnet_alloc_virtqueues(sc);
381	if (error) {
382		device_printf(dev, "cannot allocate virtqueues\n");
383		goto fail;
384	}
385
386	error = vtnet_setup_interface(sc);
387	if (error) {
388		device_printf(dev, "cannot setup interface\n");
389		goto fail;
390	}
391
392	error = virtio_setup_intr(dev, INTR_TYPE_NET);
393	if (error) {
394		device_printf(dev, "cannot setup virtqueue interrupts\n");
395		/* BMV: This will crash if during boot! */
396		ether_ifdetach(sc->vtnet_ifp);
397		goto fail;
398	}
399
400#ifdef DEV_NETMAP
401	vtnet_netmap_attach(sc);
402#endif /* DEV_NETMAP */
403
404	vtnet_start_taskqueues(sc);
405
406fail:
407	if (error)
408		vtnet_detach(dev);
409
410	return (error);
411}
412
413static int
414vtnet_detach(device_t dev)
415{
416	struct vtnet_softc *sc;
417	struct ifnet *ifp;
418
419	sc = device_get_softc(dev);
420	ifp = sc->vtnet_ifp;
421
422	if (device_is_attached(dev)) {
423		VTNET_CORE_LOCK(sc);
424		vtnet_stop(sc);
425		VTNET_CORE_UNLOCK(sc);
426
427		callout_drain(&sc->vtnet_tick_ch);
428		vtnet_drain_taskqueues(sc);
429
430		ether_ifdetach(ifp);
431	}
432
433#ifdef DEV_NETMAP
434	netmap_detach(ifp);
435#endif /* DEV_NETMAP */
436
437	vtnet_free_taskqueues(sc);
438
439	if (sc->vtnet_vlan_attach != NULL) {
440		EVENTHANDLER_DEREGISTER(vlan_config, sc->vtnet_vlan_attach);
441		sc->vtnet_vlan_attach = NULL;
442	}
443	if (sc->vtnet_vlan_detach != NULL) {
444		EVENTHANDLER_DEREGISTER(vlan_unconfg, sc->vtnet_vlan_detach);
445		sc->vtnet_vlan_detach = NULL;
446	}
447
448	ifmedia_removeall(&sc->vtnet_media);
449
450	if (ifp != NULL) {
451		if_free(ifp);
452		sc->vtnet_ifp = NULL;
453	}
454
455	vtnet_free_rxtx_queues(sc);
456	vtnet_free_rx_filters(sc);
457
458	if (sc->vtnet_ctrl_vq != NULL)
459		vtnet_free_ctrl_vq(sc);
460
461	VTNET_CORE_LOCK_DESTROY(sc);
462
463	return (0);
464}
465
466static int
467vtnet_suspend(device_t dev)
468{
469	struct vtnet_softc *sc;
470
471	sc = device_get_softc(dev);
472
473	VTNET_CORE_LOCK(sc);
474	vtnet_stop(sc);
475	sc->vtnet_flags |= VTNET_FLAG_SUSPENDED;
476	VTNET_CORE_UNLOCK(sc);
477
478	return (0);
479}
480
481static int
482vtnet_resume(device_t dev)
483{
484	struct vtnet_softc *sc;
485	struct ifnet *ifp;
486
487	sc = device_get_softc(dev);
488	ifp = sc->vtnet_ifp;
489
490	VTNET_CORE_LOCK(sc);
491	if (ifp->if_flags & IFF_UP)
492		vtnet_init_locked(sc);
493	sc->vtnet_flags &= ~VTNET_FLAG_SUSPENDED;
494	VTNET_CORE_UNLOCK(sc);
495
496	return (0);
497}
498
499static int
500vtnet_shutdown(device_t dev)
501{
502
503	/*
504	 * Suspend already does all of what we need to
505	 * do here; we just never expect to be resumed.
506	 */
507	return (vtnet_suspend(dev));
508}
509
510static int
511vtnet_attach_completed(device_t dev)
512{
513
514	vtnet_attach_disable_promisc(device_get_softc(dev));
515
516	return (0);
517}
518
519static int
520vtnet_config_change(device_t dev)
521{
522	struct vtnet_softc *sc;
523
524	sc = device_get_softc(dev);
525
526	VTNET_CORE_LOCK(sc);
527	vtnet_update_link_status(sc);
528	if (sc->vtnet_link_active != 0)
529		vtnet_tx_start_all(sc);
530	VTNET_CORE_UNLOCK(sc);
531
532	return (0);
533}
534
535static void
536vtnet_negotiate_features(struct vtnet_softc *sc)
537{
538	device_t dev;
539	uint64_t mask, features;
540
541	dev = sc->vtnet_dev;
542	mask = 0;
543
544	/*
545	 * TSO and LRO are only available when their corresponding checksum
546	 * offload feature is also negotiated.
547	 */
548	if (vtnet_tunable_int(sc, "csum_disable", vtnet_csum_disable)) {
549		mask |= VIRTIO_NET_F_CSUM | VIRTIO_NET_F_GUEST_CSUM;
550		mask |= VTNET_TSO_FEATURES | VTNET_LRO_FEATURES;
551	}
552	if (vtnet_tunable_int(sc, "tso_disable", vtnet_tso_disable))
553		mask |= VTNET_TSO_FEATURES;
554	if (vtnet_tunable_int(sc, "lro_disable", vtnet_lro_disable))
555		mask |= VTNET_LRO_FEATURES;
556#ifndef VTNET_LEGACY_TX
557	if (vtnet_tunable_int(sc, "mq_disable", vtnet_mq_disable))
558		mask |= VIRTIO_NET_F_MQ;
559#else
560	mask |= VIRTIO_NET_F_MQ;
561#endif
562
563	features = VTNET_FEATURES & ~mask;
564	sc->vtnet_features = virtio_negotiate_features(dev, features);
565
566	if (virtio_with_feature(dev, VTNET_LRO_FEATURES) &&
567	    virtio_with_feature(dev, VIRTIO_NET_F_MRG_RXBUF) == 0) {
568		/*
569		 * LRO without mergeable buffers requires special care. This
570		 * is not ideal because every receive buffer must be large
571		 * enough to hold the maximum TCP packet, the Ethernet header,
572		 * and the header. This requires up to 34 descriptors with
573		 * MCLBYTES clusters. If we do not have indirect descriptors,
574		 * LRO is disabled since the virtqueue will not contain very
575		 * many receive buffers.
576		 */
577		if (!virtio_with_feature(dev, VIRTIO_RING_F_INDIRECT_DESC)) {
578			device_printf(dev,
579			    "LRO disabled due to both mergeable buffers and "
580			    "indirect descriptors not negotiated\n");
581
582			features &= ~VTNET_LRO_FEATURES;
583			sc->vtnet_features =
584			    virtio_negotiate_features(dev, features);
585		} else
586			sc->vtnet_flags |= VTNET_FLAG_LRO_NOMRG;
587	}
588}
589
590static void
591vtnet_setup_features(struct vtnet_softc *sc)
592{
593	device_t dev;
594	int max_pairs, max;
595
596	dev = sc->vtnet_dev;
597
598	vtnet_negotiate_features(sc);
599
600	if (virtio_with_feature(dev, VIRTIO_RING_F_INDIRECT_DESC))
601		sc->vtnet_flags |= VTNET_FLAG_INDIRECT;
602	if (virtio_with_feature(dev, VIRTIO_RING_F_EVENT_IDX))
603		sc->vtnet_flags |= VTNET_FLAG_EVENT_IDX;
604
605	if (virtio_with_feature(dev, VIRTIO_NET_F_MAC)) {
606		/* This feature should always be negotiated. */
607		sc->vtnet_flags |= VTNET_FLAG_MAC;
608	}
609
610	if (virtio_with_feature(dev, VIRTIO_NET_F_MRG_RXBUF)) {
611		sc->vtnet_flags |= VTNET_FLAG_MRG_RXBUFS;
612		sc->vtnet_hdr_size = sizeof(struct virtio_net_hdr_mrg_rxbuf);
613	} else
614		sc->vtnet_hdr_size = sizeof(struct virtio_net_hdr);
615
616	if (sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS)
617		sc->vtnet_rx_nsegs = VTNET_MRG_RX_SEGS;
618	else if (sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG)
619		sc->vtnet_rx_nsegs = VTNET_MAX_RX_SEGS;
620	else
621		sc->vtnet_rx_nsegs = VTNET_MIN_RX_SEGS;
622
623	if (virtio_with_feature(dev, VIRTIO_NET_F_GSO) ||
624	    virtio_with_feature(dev, VIRTIO_NET_F_HOST_TSO4) ||
625	    virtio_with_feature(dev, VIRTIO_NET_F_HOST_TSO6))
626		sc->vtnet_tx_nsegs = VTNET_MAX_TX_SEGS;
627	else
628		sc->vtnet_tx_nsegs = VTNET_MIN_TX_SEGS;
629
630	if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_VQ)) {
631		sc->vtnet_flags |= VTNET_FLAG_CTRL_VQ;
632
633		if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_RX))
634			sc->vtnet_flags |= VTNET_FLAG_CTRL_RX;
635		if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_VLAN))
636			sc->vtnet_flags |= VTNET_FLAG_VLAN_FILTER;
637		if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_MAC_ADDR))
638			sc->vtnet_flags |= VTNET_FLAG_CTRL_MAC;
639	}
640
641	if (virtio_with_feature(dev, VIRTIO_NET_F_MQ) &&
642	    sc->vtnet_flags & VTNET_FLAG_CTRL_VQ) {
643		max_pairs = virtio_read_dev_config_2(dev,
644		    offsetof(struct virtio_net_config, max_virtqueue_pairs));
645		if (max_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
646		    max_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX)
647			max_pairs = 1;
648	} else
649		max_pairs = 1;
650
651	if (max_pairs > 1) {
652		/*
653		 * Limit the maximum number of queue pairs to the number of
654		 * CPUs or the configured maximum. The actual number of
655		 * queues that get used may be less.
656		 */
657		max = vtnet_tunable_int(sc, "mq_max_pairs", vtnet_mq_max_pairs);
658		if (max > 0 && max_pairs > max)
659			max_pairs = max;
660		if (max_pairs > mp_ncpus)
661			max_pairs = mp_ncpus;
662		if (max_pairs > VTNET_MAX_QUEUE_PAIRS)
663			max_pairs = VTNET_MAX_QUEUE_PAIRS;
664		if (max_pairs > 1)
665			sc->vtnet_flags |= VTNET_FLAG_MULTIQ;
666	}
667
668	sc->vtnet_max_vq_pairs = max_pairs;
669}
670
671static int
672vtnet_init_rxq(struct vtnet_softc *sc, int id)
673{
674	struct vtnet_rxq *rxq;
675
676	rxq = &sc->vtnet_rxqs[id];
677
678	snprintf(rxq->vtnrx_name, sizeof(rxq->vtnrx_name), "%s-rx%d",
679	    device_get_nameunit(sc->vtnet_dev), id);
680	mtx_init(&rxq->vtnrx_mtx, rxq->vtnrx_name, NULL, MTX_DEF);
681
682	rxq->vtnrx_sc = sc;
683	rxq->vtnrx_id = id;
684
685	rxq->vtnrx_sg = sglist_alloc(sc->vtnet_rx_nsegs, M_NOWAIT);
686	if (rxq->vtnrx_sg == NULL)
687		return (ENOMEM);
688
689	TASK_INIT(&rxq->vtnrx_intrtask, 0, vtnet_rxq_tq_intr, rxq);
690	rxq->vtnrx_tq = taskqueue_create(rxq->vtnrx_name, M_NOWAIT,
691	    taskqueue_thread_enqueue, &rxq->vtnrx_tq);
692
693	return (rxq->vtnrx_tq == NULL ? ENOMEM : 0);
694}
695
696static int
697vtnet_init_txq(struct vtnet_softc *sc, int id)
698{
699	struct vtnet_txq *txq;
700
701	txq = &sc->vtnet_txqs[id];
702
703	snprintf(txq->vtntx_name, sizeof(txq->vtntx_name), "%s-tx%d",
704	    device_get_nameunit(sc->vtnet_dev), id);
705	mtx_init(&txq->vtntx_mtx, txq->vtntx_name, NULL, MTX_DEF);
706
707	txq->vtntx_sc = sc;
708	txq->vtntx_id = id;
709
710	txq->vtntx_sg = sglist_alloc(sc->vtnet_tx_nsegs, M_NOWAIT);
711	if (txq->vtntx_sg == NULL)
712		return (ENOMEM);
713
714#ifndef VTNET_LEGACY_TX
715	txq->vtntx_br = buf_ring_alloc(VTNET_DEFAULT_BUFRING_SIZE, M_DEVBUF,
716	    M_NOWAIT, &txq->vtntx_mtx);
717	if (txq->vtntx_br == NULL)
718		return (ENOMEM);
719
720	TASK_INIT(&txq->vtntx_defrtask, 0, vtnet_txq_tq_deferred, txq);
721#endif
722	TASK_INIT(&txq->vtntx_intrtask, 0, vtnet_txq_tq_intr, txq);
723	txq->vtntx_tq = taskqueue_create(txq->vtntx_name, M_NOWAIT,
724	    taskqueue_thread_enqueue, &txq->vtntx_tq);
725	if (txq->vtntx_tq == NULL)
726		return (ENOMEM);
727
728	return (0);
729}
730
731static int
732vtnet_alloc_rxtx_queues(struct vtnet_softc *sc)
733{
734	int i, npairs, error;
735
736	npairs = sc->vtnet_max_vq_pairs;
737
738	sc->vtnet_rxqs = malloc(sizeof(struct vtnet_rxq) * npairs, M_DEVBUF,
739	    M_NOWAIT | M_ZERO);
740	sc->vtnet_txqs = malloc(sizeof(struct vtnet_txq) * npairs, M_DEVBUF,
741	    M_NOWAIT | M_ZERO);
742	if (sc->vtnet_rxqs == NULL || sc->vtnet_txqs == NULL)
743		return (ENOMEM);
744
745	for (i = 0; i < npairs; i++) {
746		error = vtnet_init_rxq(sc, i);
747		if (error)
748			return (error);
749		error = vtnet_init_txq(sc, i);
750		if (error)
751			return (error);
752	}
753
754	vtnet_setup_queue_sysctl(sc);
755
756	return (0);
757}
758
759static void
760vtnet_destroy_rxq(struct vtnet_rxq *rxq)
761{
762
763	rxq->vtnrx_sc = NULL;
764	rxq->vtnrx_id = -1;
765
766	if (rxq->vtnrx_sg != NULL) {
767		sglist_free(rxq->vtnrx_sg);
768		rxq->vtnrx_sg = NULL;
769	}
770
771	if (mtx_initialized(&rxq->vtnrx_mtx) != 0)
772		mtx_destroy(&rxq->vtnrx_mtx);
773}
774
775static void
776vtnet_destroy_txq(struct vtnet_txq *txq)
777{
778
779	txq->vtntx_sc = NULL;
780	txq->vtntx_id = -1;
781
782	if (txq->vtntx_sg != NULL) {
783		sglist_free(txq->vtntx_sg);
784		txq->vtntx_sg = NULL;
785	}
786
787#ifndef VTNET_LEGACY_TX
788	if (txq->vtntx_br != NULL) {
789		buf_ring_free(txq->vtntx_br, M_DEVBUF);
790		txq->vtntx_br = NULL;
791	}
792#endif
793
794	if (mtx_initialized(&txq->vtntx_mtx) != 0)
795		mtx_destroy(&txq->vtntx_mtx);
796}
797
798static void
799vtnet_free_rxtx_queues(struct vtnet_softc *sc)
800{
801	int i;
802
803	if (sc->vtnet_rxqs != NULL) {
804		for (i = 0; i < sc->vtnet_max_vq_pairs; i++)
805			vtnet_destroy_rxq(&sc->vtnet_rxqs[i]);
806		free(sc->vtnet_rxqs, M_DEVBUF);
807		sc->vtnet_rxqs = NULL;
808	}
809
810	if (sc->vtnet_txqs != NULL) {
811		for (i = 0; i < sc->vtnet_max_vq_pairs; i++)
812			vtnet_destroy_txq(&sc->vtnet_txqs[i]);
813		free(sc->vtnet_txqs, M_DEVBUF);
814		sc->vtnet_txqs = NULL;
815	}
816}
817
818static int
819vtnet_alloc_rx_filters(struct vtnet_softc *sc)
820{
821
822	if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX) {
823		sc->vtnet_mac_filter = malloc(sizeof(struct vtnet_mac_filter),
824		    M_DEVBUF, M_NOWAIT | M_ZERO);
825		if (sc->vtnet_mac_filter == NULL)
826			return (ENOMEM);
827	}
828
829	if (sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER) {
830		sc->vtnet_vlan_filter = malloc(sizeof(uint32_t) *
831		    VTNET_VLAN_FILTER_NWORDS, M_DEVBUF, M_NOWAIT | M_ZERO);
832		if (sc->vtnet_vlan_filter == NULL)
833			return (ENOMEM);
834	}
835
836	return (0);
837}
838
839static void
840vtnet_free_rx_filters(struct vtnet_softc *sc)
841{
842
843	if (sc->vtnet_mac_filter != NULL) {
844		free(sc->vtnet_mac_filter, M_DEVBUF);
845		sc->vtnet_mac_filter = NULL;
846	}
847
848	if (sc->vtnet_vlan_filter != NULL) {
849		free(sc->vtnet_vlan_filter, M_DEVBUF);
850		sc->vtnet_vlan_filter = NULL;
851	}
852}
853
854static int
855vtnet_alloc_virtqueues(struct vtnet_softc *sc)
856{
857	device_t dev;
858	struct vq_alloc_info *info;
859	struct vtnet_rxq *rxq;
860	struct vtnet_txq *txq;
861	int i, idx, flags, nvqs, error;
862
863	dev = sc->vtnet_dev;
864	flags = 0;
865
866	nvqs = sc->vtnet_max_vq_pairs * 2;
867	if (sc->vtnet_flags & VTNET_FLAG_CTRL_VQ)
868		nvqs++;
869
870	info = malloc(sizeof(struct vq_alloc_info) * nvqs, M_TEMP, M_NOWAIT);
871	if (info == NULL)
872		return (ENOMEM);
873
874	for (i = 0, idx = 0; i < sc->vtnet_max_vq_pairs; i++, idx+=2) {
875		rxq = &sc->vtnet_rxqs[i];
876		VQ_ALLOC_INFO_INIT(&info[idx], sc->vtnet_rx_nsegs,
877		    vtnet_rx_vq_intr, rxq, &rxq->vtnrx_vq,
878		    "%s-%d rx", device_get_nameunit(dev), rxq->vtnrx_id);
879
880		txq = &sc->vtnet_txqs[i];
881		VQ_ALLOC_INFO_INIT(&info[idx+1], sc->vtnet_tx_nsegs,
882		    vtnet_tx_vq_intr, txq, &txq->vtntx_vq,
883		    "%s-%d tx", device_get_nameunit(dev), txq->vtntx_id);
884	}
885
886	if (sc->vtnet_flags & VTNET_FLAG_CTRL_VQ) {
887		VQ_ALLOC_INFO_INIT(&info[idx], 0, NULL, NULL,
888		    &sc->vtnet_ctrl_vq, "%s ctrl", device_get_nameunit(dev));
889	}
890
891	/*
892	 * Enable interrupt binding if this is multiqueue. This only matters
893	 * when per-vq MSIX is available.
894	 */
895	if (sc->vtnet_flags & VTNET_FLAG_MULTIQ)
896		flags |= 0;
897
898	error = virtio_alloc_virtqueues(dev, flags, nvqs, info);
899	free(info, M_TEMP);
900
901	return (error);
902}
903
904static int
905vtnet_setup_interface(struct vtnet_softc *sc)
906{
907	device_t dev;
908	struct ifnet *ifp;
909
910	dev = sc->vtnet_dev;
911
912	ifp = sc->vtnet_ifp = if_alloc(IFT_ETHER);
913	if (ifp == NULL) {
914		device_printf(dev, "cannot allocate ifnet structure\n");
915		return (ENOSPC);
916	}
917
918	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
919	if_initbaudrate(ifp, IF_Gbps(10));	/* Approx. */
920	ifp->if_softc = sc;
921	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
922	ifp->if_init = vtnet_init;
923	ifp->if_ioctl = vtnet_ioctl;
924
925#ifndef VTNET_LEGACY_TX
926	ifp->if_transmit = vtnet_txq_mq_start;
927	ifp->if_qflush = vtnet_qflush;
928#else
929	struct virtqueue *vq = sc->vtnet_txqs[0].vtntx_vq;
930	ifp->if_start = vtnet_start;
931	IFQ_SET_MAXLEN(&ifp->if_snd, virtqueue_size(vq) - 1);
932	ifp->if_snd.ifq_drv_maxlen = virtqueue_size(vq) - 1;
933	IFQ_SET_READY(&ifp->if_snd);
934#endif
935
936	ifmedia_init(&sc->vtnet_media, IFM_IMASK, vtnet_ifmedia_upd,
937	    vtnet_ifmedia_sts);
938	ifmedia_add(&sc->vtnet_media, VTNET_MEDIATYPE, 0, NULL);
939	ifmedia_set(&sc->vtnet_media, VTNET_MEDIATYPE);
940
941	/* Read (or generate) the MAC address for the adapter. */
942	vtnet_get_hwaddr(sc);
943
944	ether_ifattach(ifp, sc->vtnet_hwaddr);
945
946	if (virtio_with_feature(dev, VIRTIO_NET_F_STATUS))
947		ifp->if_capabilities |= IFCAP_LINKSTATE;
948
949	/* Tell the upper layer(s) we support long frames. */
950	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
951	ifp->if_capabilities |= IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU;
952
953	if (virtio_with_feature(dev, VIRTIO_NET_F_CSUM)) {
954		ifp->if_capabilities |= IFCAP_TXCSUM | IFCAP_TXCSUM_IPV6;
955
956		if (virtio_with_feature(dev, VIRTIO_NET_F_GSO)) {
957			ifp->if_capabilities |= IFCAP_TSO4 | IFCAP_TSO6;
958			sc->vtnet_flags |= VTNET_FLAG_TSO_ECN;
959		} else {
960			if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_TSO4))
961				ifp->if_capabilities |= IFCAP_TSO4;
962			if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_TSO6))
963				ifp->if_capabilities |= IFCAP_TSO6;
964			if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_ECN))
965				sc->vtnet_flags |= VTNET_FLAG_TSO_ECN;
966		}
967
968		if (ifp->if_capabilities & IFCAP_TSO)
969			ifp->if_capabilities |= IFCAP_VLAN_HWTSO;
970	}
971
972	if (virtio_with_feature(dev, VIRTIO_NET_F_GUEST_CSUM)) {
973		ifp->if_capabilities |= IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6;
974
975		if (virtio_with_feature(dev, VIRTIO_NET_F_GUEST_TSO4) ||
976		    virtio_with_feature(dev, VIRTIO_NET_F_GUEST_TSO6))
977			ifp->if_capabilities |= IFCAP_LRO;
978	}
979
980	if (ifp->if_capabilities & IFCAP_HWCSUM) {
981		/*
982		 * VirtIO does not support VLAN tagging, but we can fake
983		 * it by inserting and removing the 802.1Q header during
984		 * transmit and receive. We are then able to do checksum
985		 * offloading of VLAN frames.
986		 */
987		ifp->if_capabilities |=
988		    IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_HWCSUM;
989	}
990
991	ifp->if_capenable = ifp->if_capabilities;
992
993	/*
994	 * Capabilities after here are not enabled by default.
995	 */
996
997	if (sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER) {
998		ifp->if_capabilities |= IFCAP_VLAN_HWFILTER;
999
1000		sc->vtnet_vlan_attach = EVENTHANDLER_REGISTER(vlan_config,
1001		    vtnet_register_vlan, sc, EVENTHANDLER_PRI_FIRST);
1002		sc->vtnet_vlan_detach = EVENTHANDLER_REGISTER(vlan_unconfig,
1003		    vtnet_unregister_vlan, sc, EVENTHANDLER_PRI_FIRST);
1004	}
1005
1006	vtnet_set_rx_process_limit(sc);
1007	vtnet_set_tx_intr_threshold(sc);
1008
1009	return (0);
1010}
1011
1012static int
1013vtnet_change_mtu(struct vtnet_softc *sc, int new_mtu)
1014{
1015	struct ifnet *ifp;
1016	int frame_size, clsize;
1017
1018	ifp = sc->vtnet_ifp;
1019
1020	if (new_mtu < ETHERMIN || new_mtu > VTNET_MAX_MTU)
1021		return (EINVAL);
1022
1023	frame_size = sc->vtnet_hdr_size + sizeof(struct ether_vlan_header) +
1024	    new_mtu;
1025
1026	/*
1027	 * Based on the new MTU (and hence frame size) determine which
1028	 * cluster size is most appropriate for the receive queues.
1029	 */
1030	if (frame_size <= MCLBYTES) {
1031		clsize = MCLBYTES;
1032	} else if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
1033		/* Avoid going past 9K jumbos. */
1034		if (frame_size > MJUM9BYTES)
1035			return (EINVAL);
1036		clsize = MJUM9BYTES;
1037	} else
1038		clsize = MJUMPAGESIZE;
1039
1040	ifp->if_mtu = new_mtu;
1041	sc->vtnet_rx_new_clsize = clsize;
1042
1043	if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
1044		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1045		vtnet_init_locked(sc);
1046	}
1047
1048	return (0);
1049}
1050
1051static int
1052vtnet_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
1053{
1054	struct vtnet_softc *sc;
1055	struct ifreq *ifr;
1056	int reinit, mask, error;
1057
1058	sc = ifp->if_softc;
1059	ifr = (struct ifreq *) data;
1060	error = 0;
1061
1062	switch (cmd) {
1063	case SIOCSIFMTU:
1064		if (ifp->if_mtu != ifr->ifr_mtu) {
1065			VTNET_CORE_LOCK(sc);
1066			error = vtnet_change_mtu(sc, ifr->ifr_mtu);
1067			VTNET_CORE_UNLOCK(sc);
1068		}
1069		break;
1070
1071	case SIOCSIFFLAGS:
1072		VTNET_CORE_LOCK(sc);
1073		if ((ifp->if_flags & IFF_UP) == 0) {
1074			if (ifp->if_drv_flags & IFF_DRV_RUNNING)
1075				vtnet_stop(sc);
1076		} else if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
1077			if ((ifp->if_flags ^ sc->vtnet_if_flags) &
1078			    (IFF_PROMISC | IFF_ALLMULTI)) {
1079				if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX)
1080					vtnet_rx_filter(sc);
1081				else {
1082					ifp->if_flags |= IFF_PROMISC;
1083					if ((ifp->if_flags ^ sc->vtnet_if_flags)
1084					    & IFF_ALLMULTI)
1085						error = ENOTSUP;
1086				}
1087			}
1088		} else
1089			vtnet_init_locked(sc);
1090
1091		if (error == 0)
1092			sc->vtnet_if_flags = ifp->if_flags;
1093		VTNET_CORE_UNLOCK(sc);
1094		break;
1095
1096	case SIOCADDMULTI:
1097	case SIOCDELMULTI:
1098		if ((sc->vtnet_flags & VTNET_FLAG_CTRL_RX) == 0)
1099			break;
1100		VTNET_CORE_LOCK(sc);
1101		if (ifp->if_drv_flags & IFF_DRV_RUNNING)
1102			vtnet_rx_filter_mac(sc);
1103		VTNET_CORE_UNLOCK(sc);
1104		break;
1105
1106	case SIOCSIFMEDIA:
1107	case SIOCGIFMEDIA:
1108		error = ifmedia_ioctl(ifp, ifr, &sc->vtnet_media, cmd);
1109		break;
1110
1111	case SIOCSIFCAP:
1112		VTNET_CORE_LOCK(sc);
1113		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
1114
1115		if (mask & IFCAP_TXCSUM)
1116			ifp->if_capenable ^= IFCAP_TXCSUM;
1117		if (mask & IFCAP_TXCSUM_IPV6)
1118			ifp->if_capenable ^= IFCAP_TXCSUM_IPV6;
1119		if (mask & IFCAP_TSO4)
1120			ifp->if_capenable ^= IFCAP_TSO4;
1121		if (mask & IFCAP_TSO6)
1122			ifp->if_capenable ^= IFCAP_TSO6;
1123
1124		if (mask & (IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6 | IFCAP_LRO |
1125		    IFCAP_VLAN_HWFILTER)) {
1126			/* These Rx features require us to renegotiate. */
1127			reinit = 1;
1128
1129			if (mask & IFCAP_RXCSUM)
1130				ifp->if_capenable ^= IFCAP_RXCSUM;
1131			if (mask & IFCAP_RXCSUM_IPV6)
1132				ifp->if_capenable ^= IFCAP_RXCSUM_IPV6;
1133			if (mask & IFCAP_LRO)
1134				ifp->if_capenable ^= IFCAP_LRO;
1135			if (mask & IFCAP_VLAN_HWFILTER)
1136				ifp->if_capenable ^= IFCAP_VLAN_HWFILTER;
1137		} else
1138			reinit = 0;
1139
1140		if (mask & IFCAP_VLAN_HWTSO)
1141			ifp->if_capenable ^= IFCAP_VLAN_HWTSO;
1142		if (mask & IFCAP_VLAN_HWTAGGING)
1143			ifp->if_capenable ^= IFCAP_VLAN_HWTAGGING;
1144
1145		if (reinit && (ifp->if_drv_flags & IFF_DRV_RUNNING)) {
1146			ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1147			vtnet_init_locked(sc);
1148		}
1149
1150		VTNET_CORE_UNLOCK(sc);
1151		VLAN_CAPABILITIES(ifp);
1152
1153		break;
1154
1155	default:
1156		error = ether_ioctl(ifp, cmd, data);
1157		break;
1158	}
1159
1160	VTNET_CORE_LOCK_ASSERT_NOTOWNED(sc);
1161
1162	return (error);
1163}
1164
1165static int
1166vtnet_rxq_populate(struct vtnet_rxq *rxq)
1167{
1168	struct virtqueue *vq;
1169	int nbufs, error;
1170
1171	vq = rxq->vtnrx_vq;
1172	error = ENOSPC;
1173
1174	for (nbufs = 0; !virtqueue_full(vq); nbufs++) {
1175		error = vtnet_rxq_new_buf(rxq);
1176		if (error)
1177			break;
1178	}
1179
1180	if (nbufs > 0) {
1181		virtqueue_notify(vq);
1182		/*
1183		 * EMSGSIZE signifies the virtqueue did not have enough
1184		 * entries available to hold the last mbuf. This is not
1185		 * an error.
1186		 */
1187		if (error == EMSGSIZE)
1188			error = 0;
1189	}
1190
1191	return (error);
1192}
1193
1194static void
1195vtnet_rxq_free_mbufs(struct vtnet_rxq *rxq)
1196{
1197	struct virtqueue *vq;
1198	struct mbuf *m;
1199	int last;
1200
1201	vq = rxq->vtnrx_vq;
1202	last = 0;
1203
1204	while ((m = virtqueue_drain(vq, &last)) != NULL)
1205		m_freem(m);
1206
1207	KASSERT(virtqueue_empty(vq),
1208	    ("%s: mbufs remaining in rx queue %p", __func__, rxq));
1209}
1210
1211static struct mbuf *
1212vtnet_rx_alloc_buf(struct vtnet_softc *sc, int nbufs, struct mbuf **m_tailp)
1213{
1214	struct mbuf *m_head, *m_tail, *m;
1215	int i, clsize;
1216
1217	clsize = sc->vtnet_rx_clsize;
1218
1219	KASSERT(nbufs == 1 || sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG,
1220	    ("%s: chained mbuf %d request without LRO_NOMRG", __func__, nbufs));
1221
1222	m_head = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, clsize);
1223	if (m_head == NULL)
1224		goto fail;
1225
1226	m_head->m_len = clsize;
1227	m_tail = m_head;
1228
1229	/* Allocate the rest of the chain. */
1230	for (i = 1; i < nbufs; i++) {
1231		m = m_getjcl(M_NOWAIT, MT_DATA, 0, clsize);
1232		if (m == NULL)
1233			goto fail;
1234
1235		m->m_len = clsize;
1236		m_tail->m_next = m;
1237		m_tail = m;
1238	}
1239
1240	if (m_tailp != NULL)
1241		*m_tailp = m_tail;
1242
1243	return (m_head);
1244
1245fail:
1246	sc->vtnet_stats.mbuf_alloc_failed++;
1247	m_freem(m_head);
1248
1249	return (NULL);
1250}
1251
1252/*
1253 * Slow path for when LRO without mergeable buffers is negotiated.
1254 */
1255static int
1256vtnet_rxq_replace_lro_nomgr_buf(struct vtnet_rxq *rxq, struct mbuf *m0,
1257    int len0)
1258{
1259	struct vtnet_softc *sc;
1260	struct mbuf *m, *m_prev;
1261	struct mbuf *m_new, *m_tail;
1262	int len, clsize, nreplace, error;
1263
1264	sc = rxq->vtnrx_sc;
1265	clsize = sc->vtnet_rx_clsize;
1266
1267	m_prev = NULL;
1268	m_tail = NULL;
1269	nreplace = 0;
1270
1271	m = m0;
1272	len = len0;
1273
1274	/*
1275	 * Since these mbuf chains are so large, we avoid allocating an
1276	 * entire replacement chain if possible. When the received frame
1277	 * did not consume the entire chain, the unused mbufs are moved
1278	 * to the replacement chain.
1279	 */
1280	while (len > 0) {
1281		/*
1282		 * Something is seriously wrong if we received a frame
1283		 * larger than the chain. Drop it.
1284		 */
1285		if (m == NULL) {
1286			sc->vtnet_stats.rx_frame_too_large++;
1287			return (EMSGSIZE);
1288		}
1289
1290		/* We always allocate the same cluster size. */
1291		KASSERT(m->m_len == clsize,
1292		    ("%s: mbuf size %d is not the cluster size %d",
1293		    __func__, m->m_len, clsize));
1294
1295		m->m_len = MIN(m->m_len, len);
1296		len -= m->m_len;
1297
1298		m_prev = m;
1299		m = m->m_next;
1300		nreplace++;
1301	}
1302
1303	KASSERT(nreplace <= sc->vtnet_rx_nmbufs,
1304	    ("%s: too many replacement mbufs %d max %d", __func__, nreplace,
1305	    sc->vtnet_rx_nmbufs));
1306
1307	m_new = vtnet_rx_alloc_buf(sc, nreplace, &m_tail);
1308	if (m_new == NULL) {
1309		m_prev->m_len = clsize;
1310		return (ENOBUFS);
1311	}
1312
1313	/*
1314	 * Move any unused mbufs from the received chain onto the end
1315	 * of the new chain.
1316	 */
1317	if (m_prev->m_next != NULL) {
1318		m_tail->m_next = m_prev->m_next;
1319		m_prev->m_next = NULL;
1320	}
1321
1322	error = vtnet_rxq_enqueue_buf(rxq, m_new);
1323	if (error) {
1324		/*
1325		 * BAD! We could not enqueue the replacement mbuf chain. We
1326		 * must restore the m0 chain to the original state if it was
1327		 * modified so we can subsequently discard it.
1328		 *
1329		 * NOTE: The replacement is suppose to be an identical copy
1330		 * to the one just dequeued so this is an unexpected error.
1331		 */
1332		sc->vtnet_stats.rx_enq_replacement_failed++;
1333
1334		if (m_tail->m_next != NULL) {
1335			m_prev->m_next = m_tail->m_next;
1336			m_tail->m_next = NULL;
1337		}
1338
1339		m_prev->m_len = clsize;
1340		m_freem(m_new);
1341	}
1342
1343	return (error);
1344}
1345
1346static int
1347vtnet_rxq_replace_buf(struct vtnet_rxq *rxq, struct mbuf *m, int len)
1348{
1349	struct vtnet_softc *sc;
1350	struct mbuf *m_new;
1351	int error;
1352
1353	sc = rxq->vtnrx_sc;
1354
1355	KASSERT(sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG || m->m_next == NULL,
1356	    ("%s: chained mbuf without LRO_NOMRG", __func__));
1357
1358	if (m->m_next == NULL) {
1359		/* Fast-path for the common case of just one mbuf. */
1360		if (m->m_len < len)
1361			return (EINVAL);
1362
1363		m_new = vtnet_rx_alloc_buf(sc, 1, NULL);
1364		if (m_new == NULL)
1365			return (ENOBUFS);
1366
1367		error = vtnet_rxq_enqueue_buf(rxq, m_new);
1368		if (error) {
1369			/*
1370			 * The new mbuf is suppose to be an identical
1371			 * copy of the one just dequeued so this is an
1372			 * unexpected error.
1373			 */
1374			m_freem(m_new);
1375			sc->vtnet_stats.rx_enq_replacement_failed++;
1376		} else
1377			m->m_len = len;
1378	} else
1379		error = vtnet_rxq_replace_lro_nomgr_buf(rxq, m, len);
1380
1381	return (error);
1382}
1383
1384static int
1385vtnet_rxq_enqueue_buf(struct vtnet_rxq *rxq, struct mbuf *m)
1386{
1387	struct vtnet_softc *sc;
1388	struct sglist *sg;
1389	struct vtnet_rx_header *rxhdr;
1390	uint8_t *mdata;
1391	int offset, error;
1392
1393	sc = rxq->vtnrx_sc;
1394	sg = rxq->vtnrx_sg;
1395	mdata = mtod(m, uint8_t *);
1396
1397	VTNET_RXQ_LOCK_ASSERT(rxq);
1398	KASSERT(sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG || m->m_next == NULL,
1399	    ("%s: chained mbuf without LRO_NOMRG", __func__));
1400	KASSERT(m->m_len == sc->vtnet_rx_clsize,
1401	    ("%s: unexpected cluster size %d/%d", __func__, m->m_len,
1402	     sc->vtnet_rx_clsize));
1403
1404	sglist_reset(sg);
1405	if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
1406		MPASS(sc->vtnet_hdr_size == sizeof(struct virtio_net_hdr));
1407		rxhdr = (struct vtnet_rx_header *) mdata;
1408		sglist_append(sg, &rxhdr->vrh_hdr, sc->vtnet_hdr_size);
1409		offset = sizeof(struct vtnet_rx_header);
1410	} else
1411		offset = 0;
1412
1413	sglist_append(sg, mdata + offset, m->m_len - offset);
1414	if (m->m_next != NULL) {
1415		error = sglist_append_mbuf(sg, m->m_next);
1416		MPASS(error == 0);
1417	}
1418
1419	error = virtqueue_enqueue(rxq->vtnrx_vq, m, sg, 0, sg->sg_nseg);
1420
1421	return (error);
1422}
1423
1424static int
1425vtnet_rxq_new_buf(struct vtnet_rxq *rxq)
1426{
1427	struct vtnet_softc *sc;
1428	struct mbuf *m;
1429	int error;
1430
1431	sc = rxq->vtnrx_sc;
1432
1433	m = vtnet_rx_alloc_buf(sc, sc->vtnet_rx_nmbufs, NULL);
1434	if (m == NULL)
1435		return (ENOBUFS);
1436
1437	error = vtnet_rxq_enqueue_buf(rxq, m);
1438	if (error)
1439		m_freem(m);
1440
1441	return (error);
1442}
1443
1444/*
1445 * Use the checksum offset in the VirtIO header to set the
1446 * correct CSUM_* flags.
1447 */
1448static int
1449vtnet_rxq_csum_by_offset(struct vtnet_rxq *rxq, struct mbuf *m,
1450    uint16_t eth_type, int ip_start, struct virtio_net_hdr *hdr)
1451{
1452	struct vtnet_softc *sc;
1453#if defined(INET) || defined(INET6)
1454	int offset = hdr->csum_start + hdr->csum_offset;
1455#endif
1456
1457	sc = rxq->vtnrx_sc;
1458
1459	/* Only do a basic sanity check on the offset. */
1460	switch (eth_type) {
1461#if defined(INET)
1462	case ETHERTYPE_IP:
1463		if (__predict_false(offset < ip_start + sizeof(struct ip)))
1464			return (1);
1465		break;
1466#endif
1467#if defined(INET6)
1468	case ETHERTYPE_IPV6:
1469		if (__predict_false(offset < ip_start + sizeof(struct ip6_hdr)))
1470			return (1);
1471		break;
1472#endif
1473	default:
1474		sc->vtnet_stats.rx_csum_bad_ethtype++;
1475		return (1);
1476	}
1477
1478	/*
1479	 * Use the offset to determine the appropriate CSUM_* flags. This is
1480	 * a bit dirty, but we can get by with it since the checksum offsets
1481	 * happen to be different. We assume the host host does not do IPv4
1482	 * header checksum offloading.
1483	 */
1484	switch (hdr->csum_offset) {
1485	case offsetof(struct udphdr, uh_sum):
1486	case offsetof(struct tcphdr, th_sum):
1487		m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1488		m->m_pkthdr.csum_data = 0xFFFF;
1489		break;
1490	case offsetof(struct sctphdr, checksum):
1491		m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1492		break;
1493	default:
1494		sc->vtnet_stats.rx_csum_bad_offset++;
1495		return (1);
1496	}
1497
1498	return (0);
1499}
1500
1501static int
1502vtnet_rxq_csum_by_parse(struct vtnet_rxq *rxq, struct mbuf *m,
1503    uint16_t eth_type, int ip_start, struct virtio_net_hdr *hdr)
1504{
1505	struct vtnet_softc *sc;
1506	int offset, proto;
1507
1508	sc = rxq->vtnrx_sc;
1509
1510	switch (eth_type) {
1511#if defined(INET)
1512	case ETHERTYPE_IP: {
1513		struct ip *ip;
1514		if (__predict_false(m->m_len < ip_start + sizeof(struct ip)))
1515			return (1);
1516		ip = (struct ip *)(m->m_data + ip_start);
1517		proto = ip->ip_p;
1518		offset = ip_start + (ip->ip_hl << 2);
1519		break;
1520	}
1521#endif
1522#if defined(INET6)
1523	case ETHERTYPE_IPV6:
1524		if (__predict_false(m->m_len < ip_start +
1525		    sizeof(struct ip6_hdr)))
1526			return (1);
1527		offset = ip6_lasthdr(m, ip_start, IPPROTO_IPV6, &proto);
1528		if (__predict_false(offset < 0))
1529			return (1);
1530		break;
1531#endif
1532	default:
1533		sc->vtnet_stats.rx_csum_bad_ethtype++;
1534		return (1);
1535	}
1536
1537	switch (proto) {
1538	case IPPROTO_TCP:
1539		if (__predict_false(m->m_len < offset + sizeof(struct tcphdr)))
1540			return (1);
1541		m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1542		m->m_pkthdr.csum_data = 0xFFFF;
1543		break;
1544	case IPPROTO_UDP:
1545		if (__predict_false(m->m_len < offset + sizeof(struct udphdr)))
1546			return (1);
1547		m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1548		m->m_pkthdr.csum_data = 0xFFFF;
1549		break;
1550	case IPPROTO_SCTP:
1551		if (__predict_false(m->m_len < offset + sizeof(struct sctphdr)))
1552			return (1);
1553		m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1554		break;
1555	default:
1556		/*
1557		 * For the remaining protocols, FreeBSD does not support
1558		 * checksum offloading, so the checksum will be recomputed.
1559		 */
1560#if 0
1561		if_printf(sc->vtnet_ifp, "cksum offload of unsupported "
1562		    "protocol eth_type=%#x proto=%d csum_start=%d "
1563		    "csum_offset=%d\n", __func__, eth_type, proto,
1564		    hdr->csum_start, hdr->csum_offset);
1565#endif
1566		break;
1567	}
1568
1569	return (0);
1570}
1571
1572/*
1573 * Set the appropriate CSUM_* flags. Unfortunately, the information
1574 * provided is not directly useful to us. The VirtIO header gives the
1575 * offset of the checksum, which is all Linux needs, but this is not
1576 * how FreeBSD does things. We are forced to peek inside the packet
1577 * a bit.
1578 *
1579 * It would be nice if VirtIO gave us the L4 protocol or if FreeBSD
1580 * could accept the offsets and let the stack figure it out.
1581 */
1582static int
1583vtnet_rxq_csum(struct vtnet_rxq *rxq, struct mbuf *m,
1584    struct virtio_net_hdr *hdr)
1585{
1586	struct ether_header *eh;
1587	struct ether_vlan_header *evh;
1588	uint16_t eth_type;
1589	int offset, error;
1590
1591	eh = mtod(m, struct ether_header *);
1592	eth_type = ntohs(eh->ether_type);
1593	if (eth_type == ETHERTYPE_VLAN) {
1594		/* BMV: We should handle nested VLAN tags too. */
1595		evh = mtod(m, struct ether_vlan_header *);
1596		eth_type = ntohs(evh->evl_proto);
1597		offset = sizeof(struct ether_vlan_header);
1598	} else
1599		offset = sizeof(struct ether_header);
1600
1601	if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)
1602		error = vtnet_rxq_csum_by_offset(rxq, m, eth_type, offset, hdr);
1603	else
1604		error = vtnet_rxq_csum_by_parse(rxq, m, eth_type, offset, hdr);
1605
1606	return (error);
1607}
1608
1609static void
1610vtnet_rxq_discard_merged_bufs(struct vtnet_rxq *rxq, int nbufs)
1611{
1612	struct mbuf *m;
1613
1614	while (--nbufs > 0) {
1615		m = virtqueue_dequeue(rxq->vtnrx_vq, NULL);
1616		if (m == NULL)
1617			break;
1618		vtnet_rxq_discard_buf(rxq, m);
1619	}
1620}
1621
1622static void
1623vtnet_rxq_discard_buf(struct vtnet_rxq *rxq, struct mbuf *m)
1624{
1625	int error;
1626
1627	/*
1628	 * Requeue the discarded mbuf. This should always be successful
1629	 * since it was just dequeued.
1630	 */
1631	error = vtnet_rxq_enqueue_buf(rxq, m);
1632	KASSERT(error == 0,
1633	    ("%s: cannot requeue discarded mbuf %d", __func__, error));
1634}
1635
1636static int
1637vtnet_rxq_merged_eof(struct vtnet_rxq *rxq, struct mbuf *m_head, int nbufs)
1638{
1639	struct vtnet_softc *sc;
1640	struct ifnet *ifp;
1641	struct virtqueue *vq;
1642	struct mbuf *m, *m_tail;
1643	int len;
1644
1645	sc = rxq->vtnrx_sc;
1646	vq = rxq->vtnrx_vq;
1647	ifp = sc->vtnet_ifp;
1648	m_tail = m_head;
1649
1650	while (--nbufs > 0) {
1651		m = virtqueue_dequeue(vq, &len);
1652		if (m == NULL) {
1653			rxq->vtnrx_stats.vrxs_ierrors++;
1654			goto fail;
1655		}
1656
1657		if (vtnet_rxq_new_buf(rxq) != 0) {
1658			rxq->vtnrx_stats.vrxs_iqdrops++;
1659			vtnet_rxq_discard_buf(rxq, m);
1660			if (nbufs > 1)
1661				vtnet_rxq_discard_merged_bufs(rxq, nbufs);
1662			goto fail;
1663		}
1664
1665		if (m->m_len < len)
1666			len = m->m_len;
1667
1668		m->m_len = len;
1669		m->m_flags &= ~M_PKTHDR;
1670
1671		m_head->m_pkthdr.len += len;
1672		m_tail->m_next = m;
1673		m_tail = m;
1674	}
1675
1676	return (0);
1677
1678fail:
1679	sc->vtnet_stats.rx_mergeable_failed++;
1680	m_freem(m_head);
1681
1682	return (1);
1683}
1684
1685static void
1686vtnet_rxq_input(struct vtnet_rxq *rxq, struct mbuf *m,
1687    struct virtio_net_hdr *hdr)
1688{
1689	struct vtnet_softc *sc;
1690	struct ifnet *ifp;
1691	struct ether_header *eh;
1692
1693	sc = rxq->vtnrx_sc;
1694	ifp = sc->vtnet_ifp;
1695
1696	if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING) {
1697		eh = mtod(m, struct ether_header *);
1698		if (eh->ether_type == htons(ETHERTYPE_VLAN)) {
1699			vtnet_vlan_tag_remove(m);
1700			/*
1701			 * With the 802.1Q header removed, update the
1702			 * checksum starting location accordingly.
1703			 */
1704			if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)
1705				hdr->csum_start -= ETHER_VLAN_ENCAP_LEN;
1706		}
1707	}
1708
1709	m->m_pkthdr.flowid = rxq->vtnrx_id;
1710	M_HASHTYPE_SET(m, M_HASHTYPE_OPAQUE);
1711
1712	/*
1713	 * BMV: FreeBSD does not have the UNNECESSARY and PARTIAL checksum
1714	 * distinction that Linux does. Need to reevaluate if performing
1715	 * offloading for the NEEDS_CSUM case is really appropriate.
1716	 */
1717	if (hdr->flags & (VIRTIO_NET_HDR_F_NEEDS_CSUM |
1718	    VIRTIO_NET_HDR_F_DATA_VALID)) {
1719		if (vtnet_rxq_csum(rxq, m, hdr) == 0)
1720			rxq->vtnrx_stats.vrxs_csum++;
1721		else
1722			rxq->vtnrx_stats.vrxs_csum_failed++;
1723	}
1724
1725	rxq->vtnrx_stats.vrxs_ipackets++;
1726	rxq->vtnrx_stats.vrxs_ibytes += m->m_pkthdr.len;
1727
1728	VTNET_RXQ_UNLOCK(rxq);
1729	(*ifp->if_input)(ifp, m);
1730	VTNET_RXQ_LOCK(rxq);
1731}
1732
1733static int
1734vtnet_rxq_eof(struct vtnet_rxq *rxq)
1735{
1736	struct virtio_net_hdr lhdr, *hdr;
1737	struct vtnet_softc *sc;
1738	struct ifnet *ifp;
1739	struct virtqueue *vq;
1740	struct mbuf *m;
1741	struct virtio_net_hdr_mrg_rxbuf *mhdr;
1742	int len, deq, nbufs, adjsz, count;
1743
1744	sc = rxq->vtnrx_sc;
1745	vq = rxq->vtnrx_vq;
1746	ifp = sc->vtnet_ifp;
1747	hdr = &lhdr;
1748	deq = 0;
1749	count = sc->vtnet_rx_process_limit;
1750
1751	VTNET_RXQ_LOCK_ASSERT(rxq);
1752
1753#ifdef DEV_NETMAP
1754	if (netmap_rx_irq(ifp, 0, &deq)) {
1755		return (FALSE);
1756	}
1757#endif /* DEV_NETMAP */
1758
1759	while (count-- > 0) {
1760		m = virtqueue_dequeue(vq, &len);
1761		if (m == NULL)
1762			break;
1763		deq++;
1764
1765		if (len < sc->vtnet_hdr_size + ETHER_HDR_LEN) {
1766			rxq->vtnrx_stats.vrxs_ierrors++;
1767			vtnet_rxq_discard_buf(rxq, m);
1768			continue;
1769		}
1770
1771		if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
1772			nbufs = 1;
1773			adjsz = sizeof(struct vtnet_rx_header);
1774			/*
1775			 * Account for our pad inserted between the header
1776			 * and the actual start of the frame.
1777			 */
1778			len += VTNET_RX_HEADER_PAD;
1779		} else {
1780			mhdr = mtod(m, struct virtio_net_hdr_mrg_rxbuf *);
1781			nbufs = mhdr->num_buffers;
1782			adjsz = sizeof(struct virtio_net_hdr_mrg_rxbuf);
1783		}
1784
1785		if (vtnet_rxq_replace_buf(rxq, m, len) != 0) {
1786			rxq->vtnrx_stats.vrxs_iqdrops++;
1787			vtnet_rxq_discard_buf(rxq, m);
1788			if (nbufs > 1)
1789				vtnet_rxq_discard_merged_bufs(rxq, nbufs);
1790			continue;
1791		}
1792
1793		m->m_pkthdr.len = len;
1794		m->m_pkthdr.rcvif = ifp;
1795		m->m_pkthdr.csum_flags = 0;
1796
1797		if (nbufs > 1) {
1798			/* Dequeue the rest of chain. */
1799			if (vtnet_rxq_merged_eof(rxq, m, nbufs) != 0)
1800				continue;
1801		}
1802
1803		/*
1804		 * Save copy of header before we strip it. For both mergeable
1805		 * and non-mergeable, the header is at the beginning of the
1806		 * mbuf data. We no longer need num_buffers, so always use a
1807		 * regular header.
1808		 *
1809		 * BMV: Is this memcpy() expensive? We know the mbuf data is
1810		 * still valid even after the m_adj().
1811		 */
1812		memcpy(hdr, mtod(m, void *), sizeof(struct virtio_net_hdr));
1813		m_adj(m, adjsz);
1814
1815		vtnet_rxq_input(rxq, m, hdr);
1816
1817		/* Must recheck after dropping the Rx lock. */
1818		if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
1819			break;
1820	}
1821
1822	if (deq > 0)
1823		virtqueue_notify(vq);
1824
1825	return (count > 0 ? 0 : EAGAIN);
1826}
1827
1828static void
1829vtnet_rx_vq_intr(void *xrxq)
1830{
1831	struct vtnet_softc *sc;
1832	struct vtnet_rxq *rxq;
1833	struct ifnet *ifp;
1834	int tries, more;
1835
1836	rxq = xrxq;
1837	sc = rxq->vtnrx_sc;
1838	ifp = sc->vtnet_ifp;
1839	tries = 0;
1840
1841	if (__predict_false(rxq->vtnrx_id >= sc->vtnet_act_vq_pairs)) {
1842		/*
1843		 * Ignore this interrupt. Either this is a spurious interrupt
1844		 * or multiqueue without per-VQ MSIX so every queue needs to
1845		 * be polled (a brain dead configuration we could try harder
1846		 * to avoid).
1847		 */
1848		vtnet_rxq_disable_intr(rxq);
1849		return;
1850	}
1851
1852	VTNET_RXQ_LOCK(rxq);
1853
1854again:
1855	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1856		VTNET_RXQ_UNLOCK(rxq);
1857		return;
1858	}
1859
1860	more = vtnet_rxq_eof(rxq);
1861	if (more || vtnet_rxq_enable_intr(rxq) != 0) {
1862		if (!more)
1863			vtnet_rxq_disable_intr(rxq);
1864		/*
1865		 * This is an occasional condition or race (when !more),
1866		 * so retry a few times before scheduling the taskqueue.
1867		 */
1868		if (tries++ < VTNET_INTR_DISABLE_RETRIES)
1869			goto again;
1870
1871		VTNET_RXQ_UNLOCK(rxq);
1872		rxq->vtnrx_stats.vrxs_rescheduled++;
1873		taskqueue_enqueue(rxq->vtnrx_tq, &rxq->vtnrx_intrtask);
1874	} else
1875		VTNET_RXQ_UNLOCK(rxq);
1876}
1877
1878static void
1879vtnet_rxq_tq_intr(void *xrxq, int pending)
1880{
1881	struct vtnet_softc *sc;
1882	struct vtnet_rxq *rxq;
1883	struct ifnet *ifp;
1884	int more;
1885
1886	rxq = xrxq;
1887	sc = rxq->vtnrx_sc;
1888	ifp = sc->vtnet_ifp;
1889
1890	VTNET_RXQ_LOCK(rxq);
1891
1892	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1893		VTNET_RXQ_UNLOCK(rxq);
1894		return;
1895	}
1896
1897	more = vtnet_rxq_eof(rxq);
1898	if (more || vtnet_rxq_enable_intr(rxq) != 0) {
1899		if (!more)
1900			vtnet_rxq_disable_intr(rxq);
1901		rxq->vtnrx_stats.vrxs_rescheduled++;
1902		taskqueue_enqueue(rxq->vtnrx_tq, &rxq->vtnrx_intrtask);
1903	}
1904
1905	VTNET_RXQ_UNLOCK(rxq);
1906}
1907
1908static int
1909vtnet_txq_below_threshold(struct vtnet_txq *txq)
1910{
1911	struct vtnet_softc *sc;
1912	struct virtqueue *vq;
1913
1914	sc = txq->vtntx_sc;
1915	vq = txq->vtntx_vq;
1916
1917	return (virtqueue_nfree(vq) <= sc->vtnet_tx_intr_thresh);
1918}
1919
1920static int
1921vtnet_txq_notify(struct vtnet_txq *txq)
1922{
1923	struct virtqueue *vq;
1924
1925	vq = txq->vtntx_vq;
1926
1927	txq->vtntx_watchdog = VTNET_TX_TIMEOUT;
1928	virtqueue_notify(vq);
1929
1930	if (vtnet_txq_enable_intr(txq) == 0)
1931		return (0);
1932
1933	/*
1934	 * Drain frames that were completed since last checked. If this
1935	 * causes the queue to go above the threshold, the caller should
1936	 * continue transmitting.
1937	 */
1938	if (vtnet_txq_eof(txq) != 0 && vtnet_txq_below_threshold(txq) == 0) {
1939		virtqueue_disable_intr(vq);
1940		return (1);
1941	}
1942
1943	return (0);
1944}
1945
1946static void
1947vtnet_txq_free_mbufs(struct vtnet_txq *txq)
1948{
1949	struct virtqueue *vq;
1950	struct vtnet_tx_header *txhdr;
1951	int last;
1952
1953	vq = txq->vtntx_vq;
1954	last = 0;
1955
1956	while ((txhdr = virtqueue_drain(vq, &last)) != NULL) {
1957		m_freem(txhdr->vth_mbuf);
1958		uma_zfree(vtnet_tx_header_zone, txhdr);
1959	}
1960
1961	KASSERT(virtqueue_empty(vq),
1962	    ("%s: mbufs remaining in tx queue %p", __func__, txq));
1963}
1964
1965/*
1966 * BMV: Much of this can go away once we finally have offsets in
1967 * the mbuf packet header. Bug andre@.
1968 */
1969static int
1970vtnet_txq_offload_ctx(struct vtnet_txq *txq, struct mbuf *m,
1971    int *etype, int *proto, int *start)
1972{
1973	struct vtnet_softc *sc;
1974	struct ether_vlan_header *evh;
1975	int offset;
1976
1977	sc = txq->vtntx_sc;
1978
1979	evh = mtod(m, struct ether_vlan_header *);
1980	if (evh->evl_encap_proto == htons(ETHERTYPE_VLAN)) {
1981		/* BMV: We should handle nested VLAN tags too. */
1982		*etype = ntohs(evh->evl_proto);
1983		offset = sizeof(struct ether_vlan_header);
1984	} else {
1985		*etype = ntohs(evh->evl_encap_proto);
1986		offset = sizeof(struct ether_header);
1987	}
1988
1989	switch (*etype) {
1990#if defined(INET)
1991	case ETHERTYPE_IP: {
1992		struct ip *ip, iphdr;
1993		if (__predict_false(m->m_len < offset + sizeof(struct ip))) {
1994			m_copydata(m, offset, sizeof(struct ip),
1995			    (caddr_t) &iphdr);
1996			ip = &iphdr;
1997		} else
1998			ip = (struct ip *)(m->m_data + offset);
1999		*proto = ip->ip_p;
2000		*start = offset + (ip->ip_hl << 2);
2001		break;
2002	}
2003#endif
2004#if defined(INET6)
2005	case ETHERTYPE_IPV6:
2006		*proto = -1;
2007		*start = ip6_lasthdr(m, offset, IPPROTO_IPV6, proto);
2008		/* Assert the network stack sent us a valid packet. */
2009		KASSERT(*start > offset,
2010		    ("%s: mbuf %p start %d offset %d proto %d", __func__, m,
2011		    *start, offset, *proto));
2012		break;
2013#endif
2014	default:
2015		sc->vtnet_stats.tx_csum_bad_ethtype++;
2016		return (EINVAL);
2017	}
2018
2019	return (0);
2020}
2021
2022static int
2023vtnet_txq_offload_tso(struct vtnet_txq *txq, struct mbuf *m, int eth_type,
2024    int offset, struct virtio_net_hdr *hdr)
2025{
2026	static struct timeval lastecn;
2027	static int curecn;
2028	struct vtnet_softc *sc;
2029	struct tcphdr *tcp, tcphdr;
2030
2031	sc = txq->vtntx_sc;
2032
2033	if (__predict_false(m->m_len < offset + sizeof(struct tcphdr))) {
2034		m_copydata(m, offset, sizeof(struct tcphdr), (caddr_t) &tcphdr);
2035		tcp = &tcphdr;
2036	} else
2037		tcp = (struct tcphdr *)(m->m_data + offset);
2038
2039	hdr->hdr_len = offset + (tcp->th_off << 2);
2040	hdr->gso_size = m->m_pkthdr.tso_segsz;
2041	hdr->gso_type = eth_type == ETHERTYPE_IP ? VIRTIO_NET_HDR_GSO_TCPV4 :
2042	    VIRTIO_NET_HDR_GSO_TCPV6;
2043
2044	if (tcp->th_flags & TH_CWR) {
2045		/*
2046		 * Drop if VIRTIO_NET_F_HOST_ECN was not negotiated. In FreeBSD,
2047		 * ECN support is not on a per-interface basis, but globally via
2048		 * the net.inet.tcp.ecn.enable sysctl knob. The default is off.
2049		 */
2050		if ((sc->vtnet_flags & VTNET_FLAG_TSO_ECN) == 0) {
2051			if (ppsratecheck(&lastecn, &curecn, 1))
2052				if_printf(sc->vtnet_ifp,
2053				    "TSO with ECN not negotiated with host\n");
2054			return (ENOTSUP);
2055		}
2056		hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2057	}
2058
2059	txq->vtntx_stats.vtxs_tso++;
2060
2061	return (0);
2062}
2063
2064static struct mbuf *
2065vtnet_txq_offload(struct vtnet_txq *txq, struct mbuf *m,
2066    struct virtio_net_hdr *hdr)
2067{
2068	struct vtnet_softc *sc;
2069	int flags, etype, csum_start, proto, error;
2070
2071	sc = txq->vtntx_sc;
2072	flags = m->m_pkthdr.csum_flags;
2073
2074	error = vtnet_txq_offload_ctx(txq, m, &etype, &proto, &csum_start);
2075	if (error)
2076		goto drop;
2077
2078	if ((etype == ETHERTYPE_IP && flags & VTNET_CSUM_OFFLOAD) ||
2079	    (etype == ETHERTYPE_IPV6 && flags & VTNET_CSUM_OFFLOAD_IPV6)) {
2080		/*
2081		 * We could compare the IP protocol vs the CSUM_ flag too,
2082		 * but that really should not be necessary.
2083		 */
2084		hdr->flags |= VIRTIO_NET_HDR_F_NEEDS_CSUM;
2085		hdr->csum_start = csum_start;
2086		hdr->csum_offset = m->m_pkthdr.csum_data;
2087		txq->vtntx_stats.vtxs_csum++;
2088	}
2089
2090	if (flags & CSUM_TSO) {
2091		if (__predict_false(proto != IPPROTO_TCP)) {
2092			/* Likely failed to correctly parse the mbuf. */
2093			sc->vtnet_stats.tx_tso_not_tcp++;
2094			goto drop;
2095		}
2096
2097		KASSERT(hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM,
2098		    ("%s: mbuf %p TSO without checksum offload %#x",
2099		    __func__, m, flags));
2100
2101		error = vtnet_txq_offload_tso(txq, m, etype, csum_start, hdr);
2102		if (error)
2103			goto drop;
2104	}
2105
2106	return (m);
2107
2108drop:
2109	m_freem(m);
2110	return (NULL);
2111}
2112
2113static int
2114vtnet_txq_enqueue_buf(struct vtnet_txq *txq, struct mbuf **m_head,
2115    struct vtnet_tx_header *txhdr)
2116{
2117	struct vtnet_softc *sc;
2118	struct virtqueue *vq;
2119	struct sglist *sg;
2120	struct mbuf *m;
2121	int error;
2122
2123	sc = txq->vtntx_sc;
2124	vq = txq->vtntx_vq;
2125	sg = txq->vtntx_sg;
2126	m = *m_head;
2127
2128	sglist_reset(sg);
2129	error = sglist_append(sg, &txhdr->vth_uhdr, sc->vtnet_hdr_size);
2130	KASSERT(error == 0 && sg->sg_nseg == 1,
2131	    ("%s: error %d adding header to sglist", __func__, error));
2132
2133	error = sglist_append_mbuf(sg, m);
2134	if (error) {
2135		m = m_defrag(m, M_NOWAIT);
2136		if (m == NULL)
2137			goto fail;
2138
2139		*m_head = m;
2140		sc->vtnet_stats.tx_defragged++;
2141
2142		error = sglist_append_mbuf(sg, m);
2143		if (error)
2144			goto fail;
2145	}
2146
2147	txhdr->vth_mbuf = m;
2148	error = virtqueue_enqueue(vq, txhdr, sg, sg->sg_nseg, 0);
2149
2150	return (error);
2151
2152fail:
2153	sc->vtnet_stats.tx_defrag_failed++;
2154	m_freem(*m_head);
2155	*m_head = NULL;
2156
2157	return (ENOBUFS);
2158}
2159
2160static int
2161vtnet_txq_encap(struct vtnet_txq *txq, struct mbuf **m_head)
2162{
2163	struct vtnet_tx_header *txhdr;
2164	struct virtio_net_hdr *hdr;
2165	struct mbuf *m;
2166	int error;
2167
2168	m = *m_head;
2169	M_ASSERTPKTHDR(m);
2170
2171	txhdr = uma_zalloc(vtnet_tx_header_zone, M_NOWAIT | M_ZERO);
2172	if (txhdr == NULL) {
2173		m_freem(m);
2174		*m_head = NULL;
2175		return (ENOMEM);
2176	}
2177
2178	/*
2179	 * Always use the non-mergeable header, regardless if the feature
2180	 * was negotiated. For transmit, num_buffers is always zero. The
2181	 * vtnet_hdr_size is used to enqueue the correct header size.
2182	 */
2183	hdr = &txhdr->vth_uhdr.hdr;
2184
2185	if (m->m_flags & M_VLANTAG) {
2186		m = ether_vlanencap(m, m->m_pkthdr.ether_vtag);
2187		if ((*m_head = m) == NULL) {
2188			error = ENOBUFS;
2189			goto fail;
2190		}
2191		m->m_flags &= ~M_VLANTAG;
2192	}
2193
2194	if (m->m_pkthdr.csum_flags & VTNET_CSUM_ALL_OFFLOAD) {
2195		m = vtnet_txq_offload(txq, m, hdr);
2196		if ((*m_head = m) == NULL) {
2197			error = ENOBUFS;
2198			goto fail;
2199		}
2200	}
2201
2202	error = vtnet_txq_enqueue_buf(txq, m_head, txhdr);
2203	if (error == 0)
2204		return (0);
2205
2206fail:
2207	uma_zfree(vtnet_tx_header_zone, txhdr);
2208
2209	return (error);
2210}
2211
2212#ifdef VTNET_LEGACY_TX
2213
2214static void
2215vtnet_start_locked(struct vtnet_txq *txq, struct ifnet *ifp)
2216{
2217	struct vtnet_softc *sc;
2218	struct virtqueue *vq;
2219	struct mbuf *m0;
2220	int tries, enq;
2221
2222	sc = txq->vtntx_sc;
2223	vq = txq->vtntx_vq;
2224	tries = 0;
2225
2226	VTNET_TXQ_LOCK_ASSERT(txq);
2227
2228	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ||
2229	    sc->vtnet_link_active == 0)
2230		return;
2231
2232	vtnet_txq_eof(txq);
2233
2234again:
2235	enq = 0;
2236
2237	while (!IFQ_DRV_IS_EMPTY(&ifp->if_snd)) {
2238		if (virtqueue_full(vq))
2239			break;
2240
2241		IFQ_DRV_DEQUEUE(&ifp->if_snd, m0);
2242		if (m0 == NULL)
2243			break;
2244
2245		if (vtnet_txq_encap(txq, &m0) != 0) {
2246			if (m0 != NULL)
2247				IFQ_DRV_PREPEND(&ifp->if_snd, m0);
2248			break;
2249		}
2250
2251		enq++;
2252		ETHER_BPF_MTAP(ifp, m0);
2253	}
2254
2255	if (enq > 0 && vtnet_txq_notify(txq) != 0) {
2256		if (tries++ < VTNET_NOTIFY_RETRIES)
2257			goto again;
2258
2259		txq->vtntx_stats.vtxs_rescheduled++;
2260		taskqueue_enqueue(txq->vtntx_tq, &txq->vtntx_intrtask);
2261	}
2262}
2263
2264static void
2265vtnet_start(struct ifnet *ifp)
2266{
2267	struct vtnet_softc *sc;
2268	struct vtnet_txq *txq;
2269
2270	sc = ifp->if_softc;
2271	txq = &sc->vtnet_txqs[0];
2272
2273	VTNET_TXQ_LOCK(txq);
2274	vtnet_start_locked(txq, ifp);
2275	VTNET_TXQ_UNLOCK(txq);
2276}
2277
2278#else /* !VTNET_LEGACY_TX */
2279
2280static int
2281vtnet_txq_mq_start_locked(struct vtnet_txq *txq, struct mbuf *m)
2282{
2283	struct vtnet_softc *sc;
2284	struct virtqueue *vq;
2285	struct buf_ring *br;
2286	struct ifnet *ifp;
2287	int enq, tries, error;
2288
2289	sc = txq->vtntx_sc;
2290	vq = txq->vtntx_vq;
2291	br = txq->vtntx_br;
2292	ifp = sc->vtnet_ifp;
2293	tries = 0;
2294	error = 0;
2295
2296	VTNET_TXQ_LOCK_ASSERT(txq);
2297
2298	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ||
2299	    sc->vtnet_link_active == 0) {
2300		if (m != NULL)
2301			error = drbr_enqueue(ifp, br, m);
2302		return (error);
2303	}
2304
2305	if (m != NULL) {
2306		error = drbr_enqueue(ifp, br, m);
2307		if (error)
2308			return (error);
2309	}
2310
2311	vtnet_txq_eof(txq);
2312
2313again:
2314	enq = 0;
2315
2316	while ((m = drbr_peek(ifp, br)) != NULL) {
2317		if (virtqueue_full(vq)) {
2318			drbr_putback(ifp, br, m);
2319			break;
2320		}
2321
2322		if (vtnet_txq_encap(txq, &m) != 0) {
2323			if (m != NULL)
2324				drbr_putback(ifp, br, m);
2325			else
2326				drbr_advance(ifp, br);
2327			break;
2328		}
2329		drbr_advance(ifp, br);
2330
2331		enq++;
2332		ETHER_BPF_MTAP(ifp, m);
2333	}
2334
2335	if (enq > 0 && vtnet_txq_notify(txq) != 0) {
2336		if (tries++ < VTNET_NOTIFY_RETRIES)
2337			goto again;
2338
2339		txq->vtntx_stats.vtxs_rescheduled++;
2340		taskqueue_enqueue(txq->vtntx_tq, &txq->vtntx_intrtask);
2341	}
2342
2343	return (0);
2344}
2345
2346static int
2347vtnet_txq_mq_start(struct ifnet *ifp, struct mbuf *m)
2348{
2349	struct vtnet_softc *sc;
2350	struct vtnet_txq *txq;
2351	int i, npairs, error;
2352
2353	sc = ifp->if_softc;
2354	npairs = sc->vtnet_act_vq_pairs;
2355
2356	/* check if flowid is set */
2357	if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE)
2358		i = m->m_pkthdr.flowid % npairs;
2359	else
2360		i = curcpu % npairs;
2361
2362	txq = &sc->vtnet_txqs[i];
2363
2364	if (VTNET_TXQ_TRYLOCK(txq) != 0) {
2365		error = vtnet_txq_mq_start_locked(txq, m);
2366		VTNET_TXQ_UNLOCK(txq);
2367	} else {
2368		error = drbr_enqueue(ifp, txq->vtntx_br, m);
2369		taskqueue_enqueue(txq->vtntx_tq, &txq->vtntx_defrtask);
2370	}
2371
2372	return (error);
2373}
2374
2375static void
2376vtnet_txq_tq_deferred(void *xtxq, int pending)
2377{
2378	struct vtnet_softc *sc;
2379	struct vtnet_txq *txq;
2380
2381	txq = xtxq;
2382	sc = txq->vtntx_sc;
2383
2384	VTNET_TXQ_LOCK(txq);
2385	if (!drbr_empty(sc->vtnet_ifp, txq->vtntx_br))
2386		vtnet_txq_mq_start_locked(txq, NULL);
2387	VTNET_TXQ_UNLOCK(txq);
2388}
2389
2390#endif /* VTNET_LEGACY_TX */
2391
2392static void
2393vtnet_txq_start(struct vtnet_txq *txq)
2394{
2395	struct vtnet_softc *sc;
2396	struct ifnet *ifp;
2397
2398	sc = txq->vtntx_sc;
2399	ifp = sc->vtnet_ifp;
2400
2401#ifdef VTNET_LEGACY_TX
2402	if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
2403		vtnet_start_locked(txq, ifp);
2404#else
2405	if (!drbr_empty(ifp, txq->vtntx_br))
2406		vtnet_txq_mq_start_locked(txq, NULL);
2407#endif
2408}
2409
2410static void
2411vtnet_txq_tq_intr(void *xtxq, int pending)
2412{
2413	struct vtnet_softc *sc;
2414	struct vtnet_txq *txq;
2415	struct ifnet *ifp;
2416
2417	txq = xtxq;
2418	sc = txq->vtntx_sc;
2419	ifp = sc->vtnet_ifp;
2420
2421	VTNET_TXQ_LOCK(txq);
2422
2423	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
2424		VTNET_TXQ_UNLOCK(txq);
2425		return;
2426	}
2427
2428	vtnet_txq_eof(txq);
2429	vtnet_txq_start(txq);
2430
2431	VTNET_TXQ_UNLOCK(txq);
2432}
2433
2434static int
2435vtnet_txq_eof(struct vtnet_txq *txq)
2436{
2437	struct virtqueue *vq;
2438	struct vtnet_tx_header *txhdr;
2439	struct mbuf *m;
2440	int deq;
2441
2442	vq = txq->vtntx_vq;
2443	deq = 0;
2444	VTNET_TXQ_LOCK_ASSERT(txq);
2445
2446#ifdef DEV_NETMAP
2447	if (netmap_tx_irq(txq->vtntx_sc->vtnet_ifp, txq->vtntx_id)) {
2448		virtqueue_disable_intr(vq); // XXX luigi
2449		return 0; // XXX or 1 ?
2450	}
2451#endif /* DEV_NETMAP */
2452
2453	while ((txhdr = virtqueue_dequeue(vq, NULL)) != NULL) {
2454		m = txhdr->vth_mbuf;
2455		deq++;
2456
2457		txq->vtntx_stats.vtxs_opackets++;
2458		txq->vtntx_stats.vtxs_obytes += m->m_pkthdr.len;
2459		if (m->m_flags & M_MCAST)
2460			txq->vtntx_stats.vtxs_omcasts++;
2461
2462		m_freem(m);
2463		uma_zfree(vtnet_tx_header_zone, txhdr);
2464	}
2465
2466	if (virtqueue_empty(vq))
2467		txq->vtntx_watchdog = 0;
2468
2469	return (deq);
2470}
2471
2472static void
2473vtnet_tx_vq_intr(void *xtxq)
2474{
2475	struct vtnet_softc *sc;
2476	struct vtnet_txq *txq;
2477	struct ifnet *ifp;
2478
2479	txq = xtxq;
2480	sc = txq->vtntx_sc;
2481	ifp = sc->vtnet_ifp;
2482
2483	if (__predict_false(txq->vtntx_id >= sc->vtnet_act_vq_pairs)) {
2484		/*
2485		 * Ignore this interrupt. Either this is a spurious interrupt
2486		 * or multiqueue without per-VQ MSIX so every queue needs to
2487		 * be polled (a brain dead configuration we could try harder
2488		 * to avoid).
2489		 */
2490		vtnet_txq_disable_intr(txq);
2491		return;
2492	}
2493
2494	VTNET_TXQ_LOCK(txq);
2495
2496	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
2497		VTNET_TXQ_UNLOCK(txq);
2498		return;
2499	}
2500
2501	vtnet_txq_eof(txq);
2502	vtnet_txq_start(txq);
2503
2504	VTNET_TXQ_UNLOCK(txq);
2505}
2506
2507static void
2508vtnet_tx_start_all(struct vtnet_softc *sc)
2509{
2510	struct vtnet_txq *txq;
2511	int i;
2512
2513	VTNET_CORE_LOCK_ASSERT(sc);
2514
2515	for (i = 0; i < sc->vtnet_act_vq_pairs; i++) {
2516		txq = &sc->vtnet_txqs[i];
2517
2518		VTNET_TXQ_LOCK(txq);
2519		vtnet_txq_start(txq);
2520		VTNET_TXQ_UNLOCK(txq);
2521	}
2522}
2523
2524#ifndef VTNET_LEGACY_TX
2525static void
2526vtnet_qflush(struct ifnet *ifp)
2527{
2528	struct vtnet_softc *sc;
2529	struct vtnet_txq *txq;
2530	struct mbuf *m;
2531	int i;
2532
2533	sc = ifp->if_softc;
2534
2535	for (i = 0; i < sc->vtnet_act_vq_pairs; i++) {
2536		txq = &sc->vtnet_txqs[i];
2537
2538		VTNET_TXQ_LOCK(txq);
2539		while ((m = buf_ring_dequeue_sc(txq->vtntx_br)) != NULL)
2540			m_freem(m);
2541		VTNET_TXQ_UNLOCK(txq);
2542	}
2543
2544	if_qflush(ifp);
2545}
2546#endif
2547
2548static int
2549vtnet_watchdog(struct vtnet_txq *txq)
2550{
2551	struct ifnet *ifp;
2552
2553	ifp = txq->vtntx_sc->vtnet_ifp;
2554
2555	VTNET_TXQ_LOCK(txq);
2556	if (txq->vtntx_watchdog == 1) {
2557		/*
2558		 * Only drain completed frames if the watchdog is about to
2559		 * expire. If any frames were drained, there may be enough
2560		 * free descriptors now available to transmit queued frames.
2561		 * In that case, the timer will immediately be decremented
2562		 * below, but the timeout is generous enough that should not
2563		 * be a problem.
2564		 */
2565		if (vtnet_txq_eof(txq) != 0)
2566			vtnet_txq_start(txq);
2567	}
2568
2569	if (txq->vtntx_watchdog == 0 || --txq->vtntx_watchdog) {
2570		VTNET_TXQ_UNLOCK(txq);
2571		return (0);
2572	}
2573	VTNET_TXQ_UNLOCK(txq);
2574
2575	if_printf(ifp, "watchdog timeout on queue %d\n", txq->vtntx_id);
2576	return (1);
2577}
2578
2579static void
2580vtnet_rxq_accum_stats(struct vtnet_rxq *rxq, struct vtnet_rxq_stats *accum)
2581{
2582	struct vtnet_rxq_stats *st;
2583
2584	st = &rxq->vtnrx_stats;
2585
2586	accum->vrxs_ipackets += st->vrxs_ipackets;
2587	accum->vrxs_ibytes += st->vrxs_ibytes;
2588	accum->vrxs_iqdrops += st->vrxs_iqdrops;
2589	accum->vrxs_csum += st->vrxs_csum;
2590	accum->vrxs_csum_failed += st->vrxs_csum_failed;
2591	accum->vrxs_rescheduled += st->vrxs_rescheduled;
2592}
2593
2594static void
2595vtnet_txq_accum_stats(struct vtnet_txq *txq, struct vtnet_txq_stats *accum)
2596{
2597	struct vtnet_txq_stats *st;
2598
2599	st = &txq->vtntx_stats;
2600
2601	accum->vtxs_opackets += st->vtxs_opackets;
2602	accum->vtxs_obytes += st->vtxs_obytes;
2603	accum->vtxs_csum += st->vtxs_csum;
2604	accum->vtxs_tso += st->vtxs_tso;
2605	accum->vtxs_rescheduled += st->vtxs_rescheduled;
2606}
2607
2608static void
2609vtnet_accumulate_stats(struct vtnet_softc *sc)
2610{
2611	struct ifnet *ifp;
2612	struct vtnet_statistics *st;
2613	struct vtnet_rxq_stats rxaccum;
2614	struct vtnet_txq_stats txaccum;
2615	int i;
2616
2617	ifp = sc->vtnet_ifp;
2618	st = &sc->vtnet_stats;
2619	bzero(&rxaccum, sizeof(struct vtnet_rxq_stats));
2620	bzero(&txaccum, sizeof(struct vtnet_txq_stats));
2621
2622	for (i = 0; i < sc->vtnet_max_vq_pairs; i++) {
2623		vtnet_rxq_accum_stats(&sc->vtnet_rxqs[i], &rxaccum);
2624		vtnet_txq_accum_stats(&sc->vtnet_txqs[i], &txaccum);
2625	}
2626
2627	st->rx_csum_offloaded = rxaccum.vrxs_csum;
2628	st->rx_csum_failed = rxaccum.vrxs_csum_failed;
2629	st->rx_task_rescheduled = rxaccum.vrxs_rescheduled;
2630	st->tx_csum_offloaded = txaccum.vtxs_csum;
2631	st->tx_tso_offloaded = txaccum.vtxs_tso;
2632	st->tx_task_rescheduled = txaccum.vtxs_rescheduled;
2633
2634	/*
2635	 * With the exception of if_ierrors, these ifnet statistics are
2636	 * only updated in the driver, so just set them to our accumulated
2637	 * values. if_ierrors is updated in ether_input() for malformed
2638	 * frames that we should have already discarded.
2639	 */
2640	ifp->if_ipackets = rxaccum.vrxs_ipackets;
2641	ifp->if_iqdrops = rxaccum.vrxs_iqdrops;
2642	ifp->if_ierrors = rxaccum.vrxs_ierrors;
2643	ifp->if_opackets = txaccum.vtxs_opackets;
2644#ifndef VTNET_LEGACY_TX
2645	ifp->if_obytes = txaccum.vtxs_obytes;
2646	ifp->if_omcasts = txaccum.vtxs_omcasts;
2647#endif
2648}
2649
2650static void
2651vtnet_tick(void *xsc)
2652{
2653	struct vtnet_softc *sc;
2654	struct ifnet *ifp;
2655	int i, timedout;
2656
2657	sc = xsc;
2658	ifp = sc->vtnet_ifp;
2659	timedout = 0;
2660
2661	VTNET_CORE_LOCK_ASSERT(sc);
2662	vtnet_accumulate_stats(sc);
2663
2664	for (i = 0; i < sc->vtnet_act_vq_pairs; i++)
2665		timedout |= vtnet_watchdog(&sc->vtnet_txqs[i]);
2666
2667	if (timedout != 0) {
2668		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
2669		vtnet_init_locked(sc);
2670	} else
2671		callout_schedule(&sc->vtnet_tick_ch, hz);
2672}
2673
2674static void
2675vtnet_start_taskqueues(struct vtnet_softc *sc)
2676{
2677	device_t dev;
2678	struct vtnet_rxq *rxq;
2679	struct vtnet_txq *txq;
2680	int i, error;
2681
2682	dev = sc->vtnet_dev;
2683
2684	/*
2685	 * Errors here are very difficult to recover from - we cannot
2686	 * easily fail because, if this is during boot, we will hang
2687	 * when freeing any successfully started taskqueues because
2688	 * the scheduler isn't up yet.
2689	 *
2690	 * Most drivers just ignore the return value - it only fails
2691	 * with ENOMEM so an error is not likely.
2692	 */
2693	for (i = 0; i < sc->vtnet_max_vq_pairs; i++) {
2694		rxq = &sc->vtnet_rxqs[i];
2695		error = taskqueue_start_threads(&rxq->vtnrx_tq, 1, PI_NET,
2696		    "%s rxq %d", device_get_nameunit(dev), rxq->vtnrx_id);
2697		if (error) {
2698			device_printf(dev, "failed to start rx taskq %d\n",
2699			    rxq->vtnrx_id);
2700		}
2701
2702		txq = &sc->vtnet_txqs[i];
2703		error = taskqueue_start_threads(&txq->vtntx_tq, 1, PI_NET,
2704		    "%s txq %d", device_get_nameunit(dev), txq->vtntx_id);
2705		if (error) {
2706			device_printf(dev, "failed to start tx taskq %d\n",
2707			    txq->vtntx_id);
2708		}
2709	}
2710}
2711
2712static void
2713vtnet_free_taskqueues(struct vtnet_softc *sc)
2714{
2715	struct vtnet_rxq *rxq;
2716	struct vtnet_txq *txq;
2717	int i;
2718
2719	for (i = 0; i < sc->vtnet_max_vq_pairs; i++) {
2720		rxq = &sc->vtnet_rxqs[i];
2721		if (rxq->vtnrx_tq != NULL) {
2722			taskqueue_free(rxq->vtnrx_tq);
2723			rxq->vtnrx_vq = NULL;
2724		}
2725
2726		txq = &sc->vtnet_txqs[i];
2727		if (txq->vtntx_tq != NULL) {
2728			taskqueue_free(txq->vtntx_tq);
2729			txq->vtntx_tq = NULL;
2730		}
2731	}
2732}
2733
2734static void
2735vtnet_drain_taskqueues(struct vtnet_softc *sc)
2736{
2737	struct vtnet_rxq *rxq;
2738	struct vtnet_txq *txq;
2739	int i;
2740
2741	for (i = 0; i < sc->vtnet_max_vq_pairs; i++) {
2742		rxq = &sc->vtnet_rxqs[i];
2743		if (rxq->vtnrx_tq != NULL)
2744			taskqueue_drain(rxq->vtnrx_tq, &rxq->vtnrx_intrtask);
2745
2746		txq = &sc->vtnet_txqs[i];
2747		if (txq->vtntx_tq != NULL) {
2748			taskqueue_drain(txq->vtntx_tq, &txq->vtntx_intrtask);
2749#ifndef VTNET_LEGACY_TX
2750			taskqueue_drain(txq->vtntx_tq, &txq->vtntx_defrtask);
2751#endif
2752		}
2753	}
2754}
2755
2756static void
2757vtnet_drain_rxtx_queues(struct vtnet_softc *sc)
2758{
2759	struct vtnet_rxq *rxq;
2760	struct vtnet_txq *txq;
2761	int i;
2762
2763#ifdef DEV_NETMAP
2764	if (nm_native_on(NA(sc->vtnet_ifp)))
2765		return;
2766#endif /* DEV_NETMAP */
2767
2768	for (i = 0; i < sc->vtnet_act_vq_pairs; i++) {
2769		rxq = &sc->vtnet_rxqs[i];
2770		vtnet_rxq_free_mbufs(rxq);
2771
2772		txq = &sc->vtnet_txqs[i];
2773		vtnet_txq_free_mbufs(txq);
2774	}
2775}
2776
2777static void
2778vtnet_stop_rendezvous(struct vtnet_softc *sc)
2779{
2780	struct vtnet_rxq *rxq;
2781	struct vtnet_txq *txq;
2782	int i;
2783
2784	/*
2785	 * Lock and unlock the per-queue mutex so we known the stop
2786	 * state is visible. Doing only the active queues should be
2787	 * sufficient, but it does not cost much extra to do all the
2788	 * queues. Note we hold the core mutex here too.
2789	 */
2790	for (i = 0; i < sc->vtnet_max_vq_pairs; i++) {
2791		rxq = &sc->vtnet_rxqs[i];
2792		VTNET_RXQ_LOCK(rxq);
2793		VTNET_RXQ_UNLOCK(rxq);
2794
2795		txq = &sc->vtnet_txqs[i];
2796		VTNET_TXQ_LOCK(txq);
2797		VTNET_TXQ_UNLOCK(txq);
2798	}
2799}
2800
2801static void
2802vtnet_stop(struct vtnet_softc *sc)
2803{
2804	device_t dev;
2805	struct ifnet *ifp;
2806
2807	dev = sc->vtnet_dev;
2808	ifp = sc->vtnet_ifp;
2809
2810	VTNET_CORE_LOCK_ASSERT(sc);
2811
2812	ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
2813	sc->vtnet_link_active = 0;
2814	callout_stop(&sc->vtnet_tick_ch);
2815
2816	/* Only advisory. */
2817	vtnet_disable_interrupts(sc);
2818
2819	/*
2820	 * Stop the host adapter. This resets it to the pre-initialized
2821	 * state. It will not generate any interrupts until after it is
2822	 * reinitialized.
2823	 */
2824	virtio_stop(dev);
2825	vtnet_stop_rendezvous(sc);
2826
2827	/* Free any mbufs left in the virtqueues. */
2828	vtnet_drain_rxtx_queues(sc);
2829}
2830
2831static int
2832vtnet_virtio_reinit(struct vtnet_softc *sc)
2833{
2834	device_t dev;
2835	struct ifnet *ifp;
2836	uint64_t features;
2837	int mask, error;
2838
2839	dev = sc->vtnet_dev;
2840	ifp = sc->vtnet_ifp;
2841	features = sc->vtnet_features;
2842
2843	mask = 0;
2844#if defined(INET)
2845	mask |= IFCAP_RXCSUM;
2846#endif
2847#if defined (INET6)
2848	mask |= IFCAP_RXCSUM_IPV6;
2849#endif
2850
2851	/*
2852	 * Re-negotiate with the host, removing any disabled receive
2853	 * features. Transmit features are disabled only on our side
2854	 * via if_capenable and if_hwassist.
2855	 */
2856
2857	if (ifp->if_capabilities & mask) {
2858		/*
2859		 * We require both IPv4 and IPv6 offloading to be enabled
2860		 * in order to negotiated it: VirtIO does not distinguish
2861		 * between the two.
2862		 */
2863		if ((ifp->if_capenable & mask) != mask)
2864			features &= ~VIRTIO_NET_F_GUEST_CSUM;
2865	}
2866
2867	if (ifp->if_capabilities & IFCAP_LRO) {
2868		if ((ifp->if_capenable & IFCAP_LRO) == 0)
2869			features &= ~VTNET_LRO_FEATURES;
2870	}
2871
2872	if (ifp->if_capabilities & IFCAP_VLAN_HWFILTER) {
2873		if ((ifp->if_capenable & IFCAP_VLAN_HWFILTER) == 0)
2874			features &= ~VIRTIO_NET_F_CTRL_VLAN;
2875	}
2876
2877	error = virtio_reinit(dev, features);
2878	if (error)
2879		device_printf(dev, "virtio reinit error %d\n", error);
2880
2881	return (error);
2882}
2883
2884static void
2885vtnet_init_rx_filters(struct vtnet_softc *sc)
2886{
2887	struct ifnet *ifp;
2888
2889	ifp = sc->vtnet_ifp;
2890
2891	if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX) {
2892		/* Restore promiscuous and all-multicast modes. */
2893		vtnet_rx_filter(sc);
2894		/* Restore filtered MAC addresses. */
2895		vtnet_rx_filter_mac(sc);
2896	}
2897
2898	if (ifp->if_capenable & IFCAP_VLAN_HWFILTER)
2899		vtnet_rx_filter_vlan(sc);
2900}
2901
2902static int
2903vtnet_init_rx_queues(struct vtnet_softc *sc)
2904{
2905	device_t dev;
2906	struct vtnet_rxq *rxq;
2907	int i, clsize, error;
2908
2909	dev = sc->vtnet_dev;
2910
2911	/*
2912	 * Use the new cluster size if one has been set (via a MTU
2913	 * change). Otherwise, use the standard 2K clusters.
2914	 *
2915	 * BMV: It might make sense to use page sized clusters as
2916	 * the default (depending on the features negotiated).
2917	 */
2918	if (sc->vtnet_rx_new_clsize != 0) {
2919		clsize = sc->vtnet_rx_new_clsize;
2920		sc->vtnet_rx_new_clsize = 0;
2921	} else
2922		clsize = MCLBYTES;
2923
2924	sc->vtnet_rx_clsize = clsize;
2925	sc->vtnet_rx_nmbufs = VTNET_NEEDED_RX_MBUFS(sc, clsize);
2926
2927	KASSERT(sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS ||
2928	    sc->vtnet_rx_nmbufs < sc->vtnet_rx_nsegs,
2929	    ("%s: too many rx mbufs %d for %d segments", __func__,
2930	    sc->vtnet_rx_nmbufs, sc->vtnet_rx_nsegs));
2931
2932#ifdef DEV_NETMAP
2933	if (vtnet_netmap_init_rx_buffers(sc))
2934		return 0;
2935#endif /* DEV_NETMAP */
2936
2937	for (i = 0; i < sc->vtnet_act_vq_pairs; i++) {
2938		rxq = &sc->vtnet_rxqs[i];
2939
2940		/* Hold the lock to satisfy asserts. */
2941		VTNET_RXQ_LOCK(rxq);
2942		error = vtnet_rxq_populate(rxq);
2943		VTNET_RXQ_UNLOCK(rxq);
2944
2945		if (error) {
2946			device_printf(dev,
2947			    "cannot allocate mbufs for Rx queue %d\n", i);
2948			return (error);
2949		}
2950	}
2951
2952	return (0);
2953}
2954
2955static int
2956vtnet_init_tx_queues(struct vtnet_softc *sc)
2957{
2958	struct vtnet_txq *txq;
2959	int i;
2960
2961	for (i = 0; i < sc->vtnet_act_vq_pairs; i++) {
2962		txq = &sc->vtnet_txqs[i];
2963		txq->vtntx_watchdog = 0;
2964	}
2965
2966	return (0);
2967}
2968
2969static int
2970vtnet_init_rxtx_queues(struct vtnet_softc *sc)
2971{
2972	int error;
2973
2974	error = vtnet_init_rx_queues(sc);
2975	if (error)
2976		return (error);
2977
2978	error = vtnet_init_tx_queues(sc);
2979	if (error)
2980		return (error);
2981
2982	return (0);
2983}
2984
2985static void
2986vtnet_set_active_vq_pairs(struct vtnet_softc *sc)
2987{
2988	device_t dev;
2989	int npairs;
2990
2991	dev = sc->vtnet_dev;
2992
2993	if ((sc->vtnet_flags & VTNET_FLAG_MULTIQ) == 0) {
2994		MPASS(sc->vtnet_max_vq_pairs == 1);
2995		sc->vtnet_act_vq_pairs = 1;
2996		return;
2997	}
2998
2999	/* BMV: Just use the maximum configured for now. */
3000	npairs = sc->vtnet_max_vq_pairs;
3001
3002	if (vtnet_ctrl_mq_cmd(sc, npairs) != 0) {
3003		device_printf(dev,
3004		    "cannot set active queue pairs to %d\n", npairs);
3005		npairs = 1;
3006	}
3007
3008	sc->vtnet_act_vq_pairs = npairs;
3009}
3010
3011static int
3012vtnet_reinit(struct vtnet_softc *sc)
3013{
3014	struct ifnet *ifp;
3015	int error;
3016
3017	ifp = sc->vtnet_ifp;
3018
3019	/* Use the current MAC address. */
3020	bcopy(IF_LLADDR(ifp), sc->vtnet_hwaddr, ETHER_ADDR_LEN);
3021	vtnet_set_hwaddr(sc);
3022
3023	vtnet_set_active_vq_pairs(sc);
3024
3025	ifp->if_hwassist = 0;
3026	if (ifp->if_capenable & IFCAP_TXCSUM)
3027		ifp->if_hwassist |= VTNET_CSUM_OFFLOAD;
3028	if (ifp->if_capenable & IFCAP_TXCSUM_IPV6)
3029		ifp->if_hwassist |= VTNET_CSUM_OFFLOAD_IPV6;
3030	if (ifp->if_capenable & IFCAP_TSO4)
3031		ifp->if_hwassist |= CSUM_IP_TSO;
3032	if (ifp->if_capenable & IFCAP_TSO6)
3033		ifp->if_hwassist |= CSUM_IP6_TSO;
3034
3035	if (sc->vtnet_flags & VTNET_FLAG_CTRL_VQ)
3036		vtnet_init_rx_filters(sc);
3037
3038	error = vtnet_init_rxtx_queues(sc);
3039	if (error)
3040		return (error);
3041
3042	vtnet_enable_interrupts(sc);
3043	ifp->if_drv_flags |= IFF_DRV_RUNNING;
3044
3045	return (0);
3046}
3047
3048static void
3049vtnet_init_locked(struct vtnet_softc *sc)
3050{
3051	device_t dev;
3052	struct ifnet *ifp;
3053
3054	dev = sc->vtnet_dev;
3055	ifp = sc->vtnet_ifp;
3056
3057	VTNET_CORE_LOCK_ASSERT(sc);
3058
3059	if (ifp->if_drv_flags & IFF_DRV_RUNNING)
3060		return;
3061
3062	vtnet_stop(sc);
3063
3064	/* Reinitialize with the host. */
3065	if (vtnet_virtio_reinit(sc) != 0)
3066		goto fail;
3067
3068	if (vtnet_reinit(sc) != 0)
3069		goto fail;
3070
3071	virtio_reinit_complete(dev);
3072
3073	vtnet_update_link_status(sc);
3074	callout_reset(&sc->vtnet_tick_ch, hz, vtnet_tick, sc);
3075
3076	return;
3077
3078fail:
3079	vtnet_stop(sc);
3080}
3081
3082static void
3083vtnet_init(void *xsc)
3084{
3085	struct vtnet_softc *sc;
3086
3087	sc = xsc;
3088
3089#ifdef DEV_NETMAP
3090	if (!NA(sc->vtnet_ifp)) {
3091		D("try to attach again");
3092		vtnet_netmap_attach(sc);
3093	}
3094#endif /* DEV_NETMAP */
3095
3096	VTNET_CORE_LOCK(sc);
3097	vtnet_init_locked(sc);
3098	VTNET_CORE_UNLOCK(sc);
3099}
3100
3101static void
3102vtnet_free_ctrl_vq(struct vtnet_softc *sc)
3103{
3104	struct virtqueue *vq;
3105
3106	vq = sc->vtnet_ctrl_vq;
3107
3108	/*
3109	 * The control virtqueue is only polled and therefore it should
3110	 * already be empty.
3111	 */
3112	KASSERT(virtqueue_empty(vq),
3113	    ("%s: ctrl vq %p not empty", __func__, vq));
3114}
3115
3116static void
3117vtnet_exec_ctrl_cmd(struct vtnet_softc *sc, void *cookie,
3118    struct sglist *sg, int readable, int writable)
3119{
3120	struct virtqueue *vq;
3121
3122	vq = sc->vtnet_ctrl_vq;
3123
3124	VTNET_CORE_LOCK_ASSERT(sc);
3125	KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_VQ,
3126	    ("%s: CTRL_VQ feature not negotiated", __func__));
3127
3128	if (!virtqueue_empty(vq))
3129		return;
3130	if (virtqueue_enqueue(vq, cookie, sg, readable, writable) != 0)
3131		return;
3132
3133	/*
3134	 * Poll for the response, but the command is likely already
3135	 * done when we return from the notify.
3136	 */
3137	virtqueue_notify(vq);
3138	virtqueue_poll(vq, NULL);
3139}
3140
3141static int
3142vtnet_ctrl_mac_cmd(struct vtnet_softc *sc, uint8_t *hwaddr)
3143{
3144	struct virtio_net_ctrl_hdr hdr __aligned(2);
3145	struct sglist_seg segs[3];
3146	struct sglist sg;
3147	uint8_t ack;
3148	int error;
3149
3150	hdr.class = VIRTIO_NET_CTRL_MAC;
3151	hdr.cmd = VIRTIO_NET_CTRL_MAC_ADDR_SET;
3152	ack = VIRTIO_NET_ERR;
3153
3154	sglist_init(&sg, 3, segs);
3155	error = 0;
3156	error |= sglist_append(&sg, &hdr, sizeof(struct virtio_net_ctrl_hdr));
3157	error |= sglist_append(&sg, hwaddr, ETHER_ADDR_LEN);
3158	error |= sglist_append(&sg, &ack, sizeof(uint8_t));
3159	KASSERT(error == 0 && sg.sg_nseg == 3,
3160	    ("%s: error %d adding set MAC msg to sglist", __func__, error));
3161
3162	vtnet_exec_ctrl_cmd(sc, &ack, &sg, sg.sg_nseg - 1, 1);
3163
3164	return (ack == VIRTIO_NET_OK ? 0 : EIO);
3165}
3166
3167static int
3168vtnet_ctrl_mq_cmd(struct vtnet_softc *sc, uint16_t npairs)
3169{
3170	struct sglist_seg segs[3];
3171	struct sglist sg;
3172	struct {
3173		struct virtio_net_ctrl_hdr hdr;
3174		uint8_t pad1;
3175		struct virtio_net_ctrl_mq mq;
3176		uint8_t pad2;
3177		uint8_t ack;
3178	} s __aligned(2);
3179	int error;
3180
3181	s.hdr.class = VIRTIO_NET_CTRL_MQ;
3182	s.hdr.cmd = VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET;
3183	s.mq.virtqueue_pairs = npairs;
3184	s.ack = VIRTIO_NET_ERR;
3185
3186	sglist_init(&sg, 3, segs);
3187	error = 0;
3188	error |= sglist_append(&sg, &s.hdr, sizeof(struct virtio_net_ctrl_hdr));
3189	error |= sglist_append(&sg, &s.mq, sizeof(struct virtio_net_ctrl_mq));
3190	error |= sglist_append(&sg, &s.ack, sizeof(uint8_t));
3191	KASSERT(error == 0 && sg.sg_nseg == 3,
3192	    ("%s: error %d adding MQ message to sglist", __func__, error));
3193
3194	vtnet_exec_ctrl_cmd(sc, &s.ack, &sg, sg.sg_nseg - 1, 1);
3195
3196	return (s.ack == VIRTIO_NET_OK ? 0 : EIO);
3197}
3198
3199static int
3200vtnet_ctrl_rx_cmd(struct vtnet_softc *sc, int cmd, int on)
3201{
3202	struct sglist_seg segs[3];
3203	struct sglist sg;
3204	struct {
3205		struct virtio_net_ctrl_hdr hdr;
3206		uint8_t pad1;
3207		uint8_t onoff;
3208		uint8_t pad2;
3209		uint8_t ack;
3210	} s __aligned(2);
3211	int error;
3212
3213	KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_RX,
3214	    ("%s: CTRL_RX feature not negotiated", __func__));
3215
3216	s.hdr.class = VIRTIO_NET_CTRL_RX;
3217	s.hdr.cmd = cmd;
3218	s.onoff = !!on;
3219	s.ack = VIRTIO_NET_ERR;
3220
3221	sglist_init(&sg, 3, segs);
3222	error = 0;
3223	error |= sglist_append(&sg, &s.hdr, sizeof(struct virtio_net_ctrl_hdr));
3224	error |= sglist_append(&sg, &s.onoff, sizeof(uint8_t));
3225	error |= sglist_append(&sg, &s.ack, sizeof(uint8_t));
3226	KASSERT(error == 0 && sg.sg_nseg == 3,
3227	    ("%s: error %d adding Rx message to sglist", __func__, error));
3228
3229	vtnet_exec_ctrl_cmd(sc, &s.ack, &sg, sg.sg_nseg - 1, 1);
3230
3231	return (s.ack == VIRTIO_NET_OK ? 0 : EIO);
3232}
3233
3234static int
3235vtnet_set_promisc(struct vtnet_softc *sc, int on)
3236{
3237
3238	return (vtnet_ctrl_rx_cmd(sc, VIRTIO_NET_CTRL_RX_PROMISC, on));
3239}
3240
3241static int
3242vtnet_set_allmulti(struct vtnet_softc *sc, int on)
3243{
3244
3245	return (vtnet_ctrl_rx_cmd(sc, VIRTIO_NET_CTRL_RX_ALLMULTI, on));
3246}
3247
3248/*
3249 * The device defaults to promiscuous mode for backwards compatibility.
3250 * Turn it off at attach time if possible.
3251 */
3252static void
3253vtnet_attach_disable_promisc(struct vtnet_softc *sc)
3254{
3255	struct ifnet *ifp;
3256
3257	ifp = sc->vtnet_ifp;
3258
3259	VTNET_CORE_LOCK(sc);
3260	if ((sc->vtnet_flags & VTNET_FLAG_CTRL_RX) == 0) {
3261		ifp->if_flags |= IFF_PROMISC;
3262	} else if (vtnet_set_promisc(sc, 0) != 0) {
3263		ifp->if_flags |= IFF_PROMISC;
3264		device_printf(sc->vtnet_dev,
3265		    "cannot disable default promiscuous mode\n");
3266	}
3267	VTNET_CORE_UNLOCK(sc);
3268}
3269
3270static void
3271vtnet_rx_filter(struct vtnet_softc *sc)
3272{
3273	device_t dev;
3274	struct ifnet *ifp;
3275
3276	dev = sc->vtnet_dev;
3277	ifp = sc->vtnet_ifp;
3278
3279	VTNET_CORE_LOCK_ASSERT(sc);
3280
3281	if (vtnet_set_promisc(sc, ifp->if_flags & IFF_PROMISC) != 0)
3282		device_printf(dev, "cannot %s promiscuous mode\n",
3283		    ifp->if_flags & IFF_PROMISC ? "enable" : "disable");
3284
3285	if (vtnet_set_allmulti(sc, ifp->if_flags & IFF_ALLMULTI) != 0)
3286		device_printf(dev, "cannot %s all-multicast mode\n",
3287		    ifp->if_flags & IFF_ALLMULTI ? "enable" : "disable");
3288}
3289
3290static void
3291vtnet_rx_filter_mac(struct vtnet_softc *sc)
3292{
3293	struct virtio_net_ctrl_hdr hdr __aligned(2);
3294	struct vtnet_mac_filter *filter;
3295	struct sglist_seg segs[4];
3296	struct sglist sg;
3297	struct ifnet *ifp;
3298	struct ifaddr *ifa;
3299	struct ifmultiaddr *ifma;
3300	int ucnt, mcnt, promisc, allmulti, error;
3301	uint8_t ack;
3302
3303	ifp = sc->vtnet_ifp;
3304	filter = sc->vtnet_mac_filter;
3305	ucnt = 0;
3306	mcnt = 0;
3307	promisc = 0;
3308	allmulti = 0;
3309
3310	VTNET_CORE_LOCK_ASSERT(sc);
3311	KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_RX,
3312	    ("%s: CTRL_RX feature not negotiated", __func__));
3313
3314	/* Unicast MAC addresses: */
3315	if_addr_rlock(ifp);
3316	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
3317		if (ifa->ifa_addr->sa_family != AF_LINK)
3318			continue;
3319		else if (memcmp(LLADDR((struct sockaddr_dl *)ifa->ifa_addr),
3320		    sc->vtnet_hwaddr, ETHER_ADDR_LEN) == 0)
3321			continue;
3322		else if (ucnt == VTNET_MAX_MAC_ENTRIES) {
3323			promisc = 1;
3324			break;
3325		}
3326
3327		bcopy(LLADDR((struct sockaddr_dl *)ifa->ifa_addr),
3328		    &filter->vmf_unicast.macs[ucnt], ETHER_ADDR_LEN);
3329		ucnt++;
3330	}
3331	if_addr_runlock(ifp);
3332
3333	if (promisc != 0) {
3334		filter->vmf_unicast.nentries = 0;
3335		if_printf(ifp, "more than %d MAC addresses assigned, "
3336		    "falling back to promiscuous mode\n",
3337		    VTNET_MAX_MAC_ENTRIES);
3338	} else
3339		filter->vmf_unicast.nentries = ucnt;
3340
3341	/* Multicast MAC addresses: */
3342	if_maddr_rlock(ifp);
3343	TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
3344		if (ifma->ifma_addr->sa_family != AF_LINK)
3345			continue;
3346		else if (mcnt == VTNET_MAX_MAC_ENTRIES) {
3347			allmulti = 1;
3348			break;
3349		}
3350
3351		bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
3352		    &filter->vmf_multicast.macs[mcnt], ETHER_ADDR_LEN);
3353		mcnt++;
3354	}
3355	if_maddr_runlock(ifp);
3356
3357	if (allmulti != 0) {
3358		filter->vmf_multicast.nentries = 0;
3359		if_printf(ifp, "more than %d multicast MAC addresses "
3360		    "assigned, falling back to all-multicast mode\n",
3361		    VTNET_MAX_MAC_ENTRIES);
3362	} else
3363		filter->vmf_multicast.nentries = mcnt;
3364
3365	if (promisc != 0 && allmulti != 0)
3366		goto out;
3367
3368	hdr.class = VIRTIO_NET_CTRL_MAC;
3369	hdr.cmd = VIRTIO_NET_CTRL_MAC_TABLE_SET;
3370	ack = VIRTIO_NET_ERR;
3371
3372	sglist_init(&sg, 4, segs);
3373	error = 0;
3374	error |= sglist_append(&sg, &hdr, sizeof(struct virtio_net_ctrl_hdr));
3375	error |= sglist_append(&sg, &filter->vmf_unicast,
3376	    sizeof(uint32_t) + filter->vmf_unicast.nentries * ETHER_ADDR_LEN);
3377	error |= sglist_append(&sg, &filter->vmf_multicast,
3378	    sizeof(uint32_t) + filter->vmf_multicast.nentries * ETHER_ADDR_LEN);
3379	error |= sglist_append(&sg, &ack, sizeof(uint8_t));
3380	KASSERT(error == 0 && sg.sg_nseg == 4,
3381	    ("%s: error %d adding MAC filter msg to sglist", __func__, error));
3382
3383	vtnet_exec_ctrl_cmd(sc, &ack, &sg, sg.sg_nseg - 1, 1);
3384
3385	if (ack != VIRTIO_NET_OK)
3386		if_printf(ifp, "error setting host MAC filter table\n");
3387
3388out:
3389	if (promisc != 0 && vtnet_set_promisc(sc, 1) != 0)
3390		if_printf(ifp, "cannot enable promiscuous mode\n");
3391	if (allmulti != 0 && vtnet_set_allmulti(sc, 1) != 0)
3392		if_printf(ifp, "cannot enable all-multicast mode\n");
3393}
3394
3395static int
3396vtnet_exec_vlan_filter(struct vtnet_softc *sc, int add, uint16_t tag)
3397{
3398	struct sglist_seg segs[3];
3399	struct sglist sg;
3400	struct {
3401		struct virtio_net_ctrl_hdr hdr;
3402		uint8_t pad1;
3403		uint16_t tag;
3404		uint8_t pad2;
3405		uint8_t ack;
3406	} s __aligned(2);
3407	int error;
3408
3409	s.hdr.class = VIRTIO_NET_CTRL_VLAN;
3410	s.hdr.cmd = add ? VIRTIO_NET_CTRL_VLAN_ADD : VIRTIO_NET_CTRL_VLAN_DEL;
3411	s.tag = tag;
3412	s.ack = VIRTIO_NET_ERR;
3413
3414	sglist_init(&sg, 3, segs);
3415	error = 0;
3416	error |= sglist_append(&sg, &s.hdr, sizeof(struct virtio_net_ctrl_hdr));
3417	error |= sglist_append(&sg, &s.tag, sizeof(uint16_t));
3418	error |= sglist_append(&sg, &s.ack, sizeof(uint8_t));
3419	KASSERT(error == 0 && sg.sg_nseg == 3,
3420	    ("%s: error %d adding VLAN message to sglist", __func__, error));
3421
3422	vtnet_exec_ctrl_cmd(sc, &s.ack, &sg, sg.sg_nseg - 1, 1);
3423
3424	return (s.ack == VIRTIO_NET_OK ? 0 : EIO);
3425}
3426
3427static void
3428vtnet_rx_filter_vlan(struct vtnet_softc *sc)
3429{
3430	uint32_t w;
3431	uint16_t tag;
3432	int i, bit;
3433
3434	VTNET_CORE_LOCK_ASSERT(sc);
3435	KASSERT(sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER,
3436	    ("%s: VLAN_FILTER feature not negotiated", __func__));
3437
3438	/* Enable the filter for each configured VLAN. */
3439	for (i = 0; i < VTNET_VLAN_FILTER_NWORDS; i++) {
3440		w = sc->vtnet_vlan_filter[i];
3441
3442		while ((bit = ffs(w) - 1) != -1) {
3443			w &= ~(1 << bit);
3444			tag = sizeof(w) * CHAR_BIT * i + bit;
3445
3446			if (vtnet_exec_vlan_filter(sc, 1, tag) != 0) {
3447				device_printf(sc->vtnet_dev,
3448				    "cannot enable VLAN %d filter\n", tag);
3449			}
3450		}
3451	}
3452}
3453
3454static void
3455vtnet_update_vlan_filter(struct vtnet_softc *sc, int add, uint16_t tag)
3456{
3457	struct ifnet *ifp;
3458	int idx, bit;
3459
3460	ifp = sc->vtnet_ifp;
3461	idx = (tag >> 5) & 0x7F;
3462	bit = tag & 0x1F;
3463
3464	if (tag == 0 || tag > 4095)
3465		return;
3466
3467	VTNET_CORE_LOCK(sc);
3468
3469	if (add)
3470		sc->vtnet_vlan_filter[idx] |= (1 << bit);
3471	else
3472		sc->vtnet_vlan_filter[idx] &= ~(1 << bit);
3473
3474	if (ifp->if_capenable & IFCAP_VLAN_HWFILTER &&
3475	    vtnet_exec_vlan_filter(sc, add, tag) != 0) {
3476		device_printf(sc->vtnet_dev,
3477		    "cannot %s VLAN %d %s the host filter table\n",
3478		    add ? "add" : "remove", tag, add ? "to" : "from");
3479	}
3480
3481	VTNET_CORE_UNLOCK(sc);
3482}
3483
3484static void
3485vtnet_register_vlan(void *arg, struct ifnet *ifp, uint16_t tag)
3486{
3487
3488	if (ifp->if_softc != arg)
3489		return;
3490
3491	vtnet_update_vlan_filter(arg, 1, tag);
3492}
3493
3494static void
3495vtnet_unregister_vlan(void *arg, struct ifnet *ifp, uint16_t tag)
3496{
3497
3498	if (ifp->if_softc != arg)
3499		return;
3500
3501	vtnet_update_vlan_filter(arg, 0, tag);
3502}
3503
3504static int
3505vtnet_is_link_up(struct vtnet_softc *sc)
3506{
3507	device_t dev;
3508	struct ifnet *ifp;
3509	uint16_t status;
3510
3511	dev = sc->vtnet_dev;
3512	ifp = sc->vtnet_ifp;
3513
3514	if ((ifp->if_capabilities & IFCAP_LINKSTATE) == 0)
3515		status = VIRTIO_NET_S_LINK_UP;
3516	else
3517		status = virtio_read_dev_config_2(dev,
3518		    offsetof(struct virtio_net_config, status));
3519
3520	return ((status & VIRTIO_NET_S_LINK_UP) != 0);
3521}
3522
3523static void
3524vtnet_update_link_status(struct vtnet_softc *sc)
3525{
3526	struct ifnet *ifp;
3527	int link;
3528
3529	ifp = sc->vtnet_ifp;
3530
3531	VTNET_CORE_LOCK_ASSERT(sc);
3532	link = vtnet_is_link_up(sc);
3533
3534	/* Notify if the link status has changed. */
3535	if (link != 0 && sc->vtnet_link_active == 0) {
3536		sc->vtnet_link_active = 1;
3537		if_link_state_change(ifp, LINK_STATE_UP);
3538	} else if (link == 0 && sc->vtnet_link_active != 0) {
3539		sc->vtnet_link_active = 0;
3540		if_link_state_change(ifp, LINK_STATE_DOWN);
3541	}
3542}
3543
3544static int
3545vtnet_ifmedia_upd(struct ifnet *ifp)
3546{
3547	struct vtnet_softc *sc;
3548	struct ifmedia *ifm;
3549
3550	sc = ifp->if_softc;
3551	ifm = &sc->vtnet_media;
3552
3553	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
3554		return (EINVAL);
3555
3556	return (0);
3557}
3558
3559static void
3560vtnet_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
3561{
3562	struct vtnet_softc *sc;
3563
3564	sc = ifp->if_softc;
3565
3566	ifmr->ifm_status = IFM_AVALID;
3567	ifmr->ifm_active = IFM_ETHER;
3568
3569	VTNET_CORE_LOCK(sc);
3570	if (vtnet_is_link_up(sc) != 0) {
3571		ifmr->ifm_status |= IFM_ACTIVE;
3572		ifmr->ifm_active |= VTNET_MEDIATYPE;
3573	} else
3574		ifmr->ifm_active |= IFM_NONE;
3575	VTNET_CORE_UNLOCK(sc);
3576}
3577
3578static void
3579vtnet_set_hwaddr(struct vtnet_softc *sc)
3580{
3581	device_t dev;
3582	int i;
3583
3584	dev = sc->vtnet_dev;
3585
3586	if (sc->vtnet_flags & VTNET_FLAG_CTRL_MAC) {
3587		if (vtnet_ctrl_mac_cmd(sc, sc->vtnet_hwaddr) != 0)
3588			device_printf(dev, "unable to set MAC address\n");
3589	} else if (sc->vtnet_flags & VTNET_FLAG_MAC) {
3590		for (i = 0; i < ETHER_ADDR_LEN; i++) {
3591			virtio_write_dev_config_1(dev,
3592			    offsetof(struct virtio_net_config, mac) + i,
3593			    sc->vtnet_hwaddr[i]);
3594		}
3595	}
3596}
3597
3598static void
3599vtnet_get_hwaddr(struct vtnet_softc *sc)
3600{
3601	device_t dev;
3602	int i;
3603
3604	dev = sc->vtnet_dev;
3605
3606	if ((sc->vtnet_flags & VTNET_FLAG_MAC) == 0) {
3607		/*
3608		 * Generate a random locally administered unicast address.
3609		 *
3610		 * It would be nice to generate the same MAC address across
3611		 * reboots, but it seems all the hosts currently available
3612		 * support the MAC feature, so this isn't too important.
3613		 */
3614		sc->vtnet_hwaddr[0] = 0xB2;
3615		arc4rand(&sc->vtnet_hwaddr[1], ETHER_ADDR_LEN - 1, 0);
3616		vtnet_set_hwaddr(sc);
3617		return;
3618	}
3619
3620	for (i = 0; i < ETHER_ADDR_LEN; i++) {
3621		sc->vtnet_hwaddr[i] = virtio_read_dev_config_1(dev,
3622		    offsetof(struct virtio_net_config, mac) + i);
3623	}
3624}
3625
3626static void
3627vtnet_vlan_tag_remove(struct mbuf *m)
3628{
3629	struct ether_vlan_header *evh;
3630
3631	evh = mtod(m, struct ether_vlan_header *);
3632	m->m_pkthdr.ether_vtag = ntohs(evh->evl_tag);
3633	m->m_flags |= M_VLANTAG;
3634
3635	/* Strip the 802.1Q header. */
3636	bcopy((char *) evh, (char *) evh + ETHER_VLAN_ENCAP_LEN,
3637	    ETHER_HDR_LEN - ETHER_TYPE_LEN);
3638	m_adj(m, ETHER_VLAN_ENCAP_LEN);
3639}
3640
3641static void
3642vtnet_set_rx_process_limit(struct vtnet_softc *sc)
3643{
3644	int limit;
3645
3646	limit = vtnet_tunable_int(sc, "rx_process_limit",
3647	    vtnet_rx_process_limit);
3648	if (limit < 0)
3649		limit = INT_MAX;
3650	sc->vtnet_rx_process_limit = limit;
3651}
3652
3653static void
3654vtnet_set_tx_intr_threshold(struct vtnet_softc *sc)
3655{
3656	device_t dev;
3657	int size, thresh;
3658
3659	dev = sc->vtnet_dev;
3660	size = virtqueue_size(sc->vtnet_txqs[0].vtntx_vq);
3661
3662	/*
3663	 * The Tx interrupt is disabled until the queue free count falls
3664	 * below our threshold. Completed frames are drained from the Tx
3665	 * virtqueue before transmitting new frames and in the watchdog
3666	 * callout, so the frequency of Tx interrupts is greatly reduced,
3667	 * at the cost of not freeing mbufs as quickly as they otherwise
3668	 * would be.
3669	 *
3670	 * N.B. We assume all the Tx queues are the same size.
3671	 */
3672	thresh = size / 4;
3673
3674	/*
3675	 * Without indirect descriptors, leave enough room for the most
3676	 * segments we handle.
3677	 */
3678	if ((sc->vtnet_flags & VTNET_FLAG_INDIRECT) == 0 &&
3679	    thresh < sc->vtnet_tx_nsegs)
3680		thresh = sc->vtnet_tx_nsegs;
3681
3682	sc->vtnet_tx_intr_thresh = thresh;
3683}
3684
3685static void
3686vtnet_setup_rxq_sysctl(struct sysctl_ctx_list *ctx,
3687    struct sysctl_oid_list *child, struct vtnet_rxq *rxq)
3688{
3689	struct sysctl_oid *node;
3690	struct sysctl_oid_list *list;
3691	struct vtnet_rxq_stats *stats;
3692	char namebuf[16];
3693
3694	snprintf(namebuf, sizeof(namebuf), "rxq%d", rxq->vtnrx_id);
3695	node = SYSCTL_ADD_NODE(ctx, child, OID_AUTO, namebuf,
3696	    CTLFLAG_RD, NULL, "Receive Queue");
3697	list = SYSCTL_CHILDREN(node);
3698
3699	stats = &rxq->vtnrx_stats;
3700
3701	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "ipackets", CTLFLAG_RD,
3702	    &stats->vrxs_ipackets, "Receive packets");
3703	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "ibytes", CTLFLAG_RD,
3704	    &stats->vrxs_ibytes, "Receive bytes");
3705	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "iqdrops", CTLFLAG_RD,
3706	    &stats->vrxs_iqdrops, "Receive drops");
3707	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "ierrors", CTLFLAG_RD,
3708	    &stats->vrxs_ierrors, "Receive errors");
3709	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "csum", CTLFLAG_RD,
3710	    &stats->vrxs_csum, "Receive checksum offloaded");
3711	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "csum_failed", CTLFLAG_RD,
3712	    &stats->vrxs_csum_failed, "Receive checksum offload failed");
3713	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "rescheduled", CTLFLAG_RD,
3714	    &stats->vrxs_rescheduled,
3715	    "Receive interrupt handler rescheduled");
3716}
3717
3718static void
3719vtnet_setup_txq_sysctl(struct sysctl_ctx_list *ctx,
3720    struct sysctl_oid_list *child, struct vtnet_txq *txq)
3721{
3722	struct sysctl_oid *node;
3723	struct sysctl_oid_list *list;
3724	struct vtnet_txq_stats *stats;
3725	char namebuf[16];
3726
3727	snprintf(namebuf, sizeof(namebuf), "txq%d", txq->vtntx_id);
3728	node = SYSCTL_ADD_NODE(ctx, child, OID_AUTO, namebuf,
3729	    CTLFLAG_RD, NULL, "Transmit Queue");
3730	list = SYSCTL_CHILDREN(node);
3731
3732	stats = &txq->vtntx_stats;
3733
3734	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "opackets", CTLFLAG_RD,
3735	    &stats->vtxs_opackets, "Transmit packets");
3736	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "obytes", CTLFLAG_RD,
3737	    &stats->vtxs_obytes, "Transmit bytes");
3738	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "omcasts", CTLFLAG_RD,
3739	    &stats->vtxs_omcasts, "Transmit multicasts");
3740	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "csum", CTLFLAG_RD,
3741	    &stats->vtxs_csum, "Transmit checksum offloaded");
3742	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "tso", CTLFLAG_RD,
3743	    &stats->vtxs_tso, "Transmit segmentation offloaded");
3744	SYSCTL_ADD_UQUAD(ctx, list, OID_AUTO, "rescheduled", CTLFLAG_RD,
3745	    &stats->vtxs_rescheduled,
3746	    "Transmit interrupt handler rescheduled");
3747}
3748
3749static void
3750vtnet_setup_queue_sysctl(struct vtnet_softc *sc)
3751{
3752	device_t dev;
3753	struct sysctl_ctx_list *ctx;
3754	struct sysctl_oid *tree;
3755	struct sysctl_oid_list *child;
3756	int i;
3757
3758	dev = sc->vtnet_dev;
3759	ctx = device_get_sysctl_ctx(dev);
3760	tree = device_get_sysctl_tree(dev);
3761	child = SYSCTL_CHILDREN(tree);
3762
3763	for (i = 0; i < sc->vtnet_max_vq_pairs; i++) {
3764		vtnet_setup_rxq_sysctl(ctx, child, &sc->vtnet_rxqs[i]);
3765		vtnet_setup_txq_sysctl(ctx, child, &sc->vtnet_txqs[i]);
3766	}
3767}
3768
3769static void
3770vtnet_setup_stat_sysctl(struct sysctl_ctx_list *ctx,
3771    struct sysctl_oid_list *child, struct vtnet_softc *sc)
3772{
3773	struct vtnet_statistics *stats;
3774
3775	stats = &sc->vtnet_stats;
3776
3777	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "mbuf_alloc_failed",
3778	    CTLFLAG_RD, &stats->mbuf_alloc_failed,
3779	    "Mbuf cluster allocation failures");
3780
3781	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_frame_too_large",
3782	    CTLFLAG_RD, &stats->rx_frame_too_large,
3783	    "Received frame larger than the mbuf chain");
3784	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_enq_replacement_failed",
3785	    CTLFLAG_RD, &stats->rx_enq_replacement_failed,
3786	    "Enqueuing the replacement receive mbuf failed");
3787	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_mergeable_failed",
3788	    CTLFLAG_RD, &stats->rx_mergeable_failed,
3789	    "Mergeable buffers receive failures");
3790	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_csum_bad_ethtype",
3791	    CTLFLAG_RD, &stats->rx_csum_bad_ethtype,
3792	    "Received checksum offloaded buffer with unsupported "
3793	    "Ethernet type");
3794	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_csum_bad_ipproto",
3795	    CTLFLAG_RD, &stats->rx_csum_bad_ipproto,
3796	    "Received checksum offloaded buffer with incorrect IP protocol");
3797	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_csum_bad_offset",
3798	    CTLFLAG_RD, &stats->rx_csum_bad_offset,
3799	    "Received checksum offloaded buffer with incorrect offset");
3800	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_csum_bad_proto",
3801	    CTLFLAG_RD, &stats->rx_csum_bad_proto,
3802	    "Received checksum offloaded buffer with incorrect protocol");
3803	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_csum_failed",
3804	    CTLFLAG_RD, &stats->rx_csum_failed,
3805	    "Received buffer checksum offload failed");
3806	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_csum_offloaded",
3807	    CTLFLAG_RD, &stats->rx_csum_offloaded,
3808	    "Received buffer checksum offload succeeded");
3809	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "rx_task_rescheduled",
3810	    CTLFLAG_RD, &stats->rx_task_rescheduled,
3811	    "Times the receive interrupt task rescheduled itself");
3812
3813	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "tx_csum_bad_ethtype",
3814	    CTLFLAG_RD, &stats->tx_csum_bad_ethtype,
3815	    "Aborted transmit of checksum offloaded buffer with unknown "
3816	    "Ethernet type");
3817	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "tx_tso_bad_ethtype",
3818	    CTLFLAG_RD, &stats->tx_tso_bad_ethtype,
3819	    "Aborted transmit of TSO buffer with unknown Ethernet type");
3820	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "tx_tso_not_tcp",
3821	    CTLFLAG_RD, &stats->tx_tso_not_tcp,
3822	    "Aborted transmit of TSO buffer with non TCP protocol");
3823	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "tx_defragged",
3824	    CTLFLAG_RD, &stats->tx_defragged,
3825	    "Transmit mbufs defragged");
3826	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "tx_defrag_failed",
3827	    CTLFLAG_RD, &stats->tx_defrag_failed,
3828	    "Aborted transmit of buffer because defrag failed");
3829	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "tx_csum_offloaded",
3830	    CTLFLAG_RD, &stats->tx_csum_offloaded,
3831	    "Offloaded checksum of transmitted buffer");
3832	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "tx_tso_offloaded",
3833	    CTLFLAG_RD, &stats->tx_tso_offloaded,
3834	    "Segmentation offload of transmitted buffer");
3835	SYSCTL_ADD_UQUAD(ctx, child, OID_AUTO, "tx_task_rescheduled",
3836	    CTLFLAG_RD, &stats->tx_task_rescheduled,
3837	    "Times the transmit interrupt task rescheduled itself");
3838}
3839
3840static void
3841vtnet_setup_sysctl(struct vtnet_softc *sc)
3842{
3843	device_t dev;
3844	struct sysctl_ctx_list *ctx;
3845	struct sysctl_oid *tree;
3846	struct sysctl_oid_list *child;
3847
3848	dev = sc->vtnet_dev;
3849	ctx = device_get_sysctl_ctx(dev);
3850	tree = device_get_sysctl_tree(dev);
3851	child = SYSCTL_CHILDREN(tree);
3852
3853	SYSCTL_ADD_INT(ctx, child, OID_AUTO, "max_vq_pairs",
3854	    CTLFLAG_RD, &sc->vtnet_max_vq_pairs, 0,
3855	    "Maximum number of supported virtqueue pairs");
3856	SYSCTL_ADD_INT(ctx, child, OID_AUTO, "act_vq_pairs",
3857	    CTLFLAG_RD, &sc->vtnet_act_vq_pairs, 0,
3858	    "Number of active virtqueue pairs");
3859
3860	vtnet_setup_stat_sysctl(ctx, child, sc);
3861}
3862
3863static int
3864vtnet_rxq_enable_intr(struct vtnet_rxq *rxq)
3865{
3866
3867	return (virtqueue_enable_intr(rxq->vtnrx_vq));
3868}
3869
3870static void
3871vtnet_rxq_disable_intr(struct vtnet_rxq *rxq)
3872{
3873
3874	virtqueue_disable_intr(rxq->vtnrx_vq);
3875}
3876
3877static int
3878vtnet_txq_enable_intr(struct vtnet_txq *txq)
3879{
3880	struct virtqueue *vq;
3881
3882	vq = txq->vtntx_vq;
3883
3884	if (vtnet_txq_below_threshold(txq) != 0)
3885		return (virtqueue_postpone_intr(vq, VQ_POSTPONE_LONG));
3886
3887	/*
3888	 * The free count is above our threshold. Keep the Tx interrupt
3889	 * disabled until the queue is fuller.
3890	 */
3891	return (0);
3892}
3893
3894static void
3895vtnet_txq_disable_intr(struct vtnet_txq *txq)
3896{
3897
3898	virtqueue_disable_intr(txq->vtntx_vq);
3899}
3900
3901static void
3902vtnet_enable_rx_interrupts(struct vtnet_softc *sc)
3903{
3904	int i;
3905
3906	for (i = 0; i < sc->vtnet_act_vq_pairs; i++)
3907		vtnet_rxq_enable_intr(&sc->vtnet_rxqs[i]);
3908}
3909
3910static void
3911vtnet_enable_tx_interrupts(struct vtnet_softc *sc)
3912{
3913	int i;
3914
3915	for (i = 0; i < sc->vtnet_act_vq_pairs; i++)
3916		vtnet_txq_enable_intr(&sc->vtnet_txqs[i]);
3917}
3918
3919static void
3920vtnet_enable_interrupts(struct vtnet_softc *sc)
3921{
3922
3923	vtnet_enable_rx_interrupts(sc);
3924	vtnet_enable_tx_interrupts(sc);
3925}
3926
3927static void
3928vtnet_disable_rx_interrupts(struct vtnet_softc *sc)
3929{
3930	int i;
3931
3932	for (i = 0; i < sc->vtnet_act_vq_pairs; i++)
3933		vtnet_rxq_disable_intr(&sc->vtnet_rxqs[i]);
3934}
3935
3936static void
3937vtnet_disable_tx_interrupts(struct vtnet_softc *sc)
3938{
3939	int i;
3940
3941	for (i = 0; i < sc->vtnet_act_vq_pairs; i++)
3942		vtnet_txq_disable_intr(&sc->vtnet_txqs[i]);
3943}
3944
3945static void
3946vtnet_disable_interrupts(struct vtnet_softc *sc)
3947{
3948
3949	vtnet_disable_rx_interrupts(sc);
3950	vtnet_disable_tx_interrupts(sc);
3951}
3952
3953static int
3954vtnet_tunable_int(struct vtnet_softc *sc, const char *knob, int def)
3955{
3956	char path[64];
3957
3958	snprintf(path, sizeof(path),
3959	    "hw.vtnet.%d.%s", device_get_unit(sc->vtnet_dev), knob);
3960	TUNABLE_INT_FETCH(path, &def);
3961
3962	return (def);
3963}
3964