xref: /dflybsd-src/sys/dev/virtual/virtio/net/if_vtnet.c (revision e19e5bbc20dd1d64f1833c5d0ac7a605c8e9bfa0)
1 /*-
2  * Copyright (c) 2011, Bryan Venteicher <bryanv@daemoninthecloset.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 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/kernel.h>
34 #include <sys/sockio.h>
35 #include <sys/mbuf.h>
36 #include <sys/malloc.h>
37 #include <sys/module.h>
38 #include <sys/socket.h>
39 #include <sys/sysctl.h>
40 #include <sys/taskqueue.h>
41 #include <sys/random.h>
42 #include <sys/sglist.h>
43 #include <sys/serialize.h>
44 #include <sys/bus.h>
45 #include <sys/rman.h>
46 
47 #include <net/ethernet.h>
48 #include <net/if.h>
49 #include <net/if_arp.h>
50 #include <net/if_dl.h>
51 #include <net/if_types.h>
52 #include <net/if_media.h>
53 #include <net/vlan/if_vlan_var.h>
54 #include <net/vlan/if_vlan_ether.h>
55 #include <net/ifq_var.h>
56 
57 #include <net/bpf.h>
58 
59 #include <netinet/in_systm.h>
60 #include <netinet/in.h>
61 #include <netinet/ip.h>
62 #include <netinet/ip6.h>
63 #include <netinet/udp.h>
64 #include <netinet/tcp.h>
65 #include <netinet/sctp.h>
66 
67 #include <dev/virtual/virtio/virtio/virtio.h>
68 #include <dev/virtual/virtio/virtio/virtqueue.h>
69 
70 #include "virtio_net.h"
71 #include "virtio_if.h"
72 
73 struct vtnet_statistics {
74 	unsigned long		mbuf_alloc_failed;
75 
76 	unsigned long		rx_frame_too_large;
77 	unsigned long		rx_enq_replacement_failed;
78 	unsigned long		rx_mergeable_failed;
79 	unsigned long		rx_csum_bad_ethtype;
80 	unsigned long		rx_csum_bad_start;
81 	unsigned long		rx_csum_bad_ipproto;
82 	unsigned long		rx_csum_bad_offset;
83 	unsigned long		rx_csum_failed;
84 	unsigned long		rx_csum_offloaded;
85 	unsigned long		rx_task_rescheduled;
86 
87 	unsigned long		tx_csum_offloaded;
88 	unsigned long		tx_tso_offloaded;
89 	unsigned long		tx_csum_bad_ethtype;
90 	unsigned long		tx_tso_bad_ethtype;
91 	unsigned long		tx_task_rescheduled;
92 };
93 
94 struct vtnet_softc {
95 	device_t		vtnet_dev;
96 	struct ifnet		*vtnet_ifp;
97 	struct lwkt_serialize	vtnet_slz;
98 
99 	uint32_t		vtnet_flags;
100 #define VTNET_FLAG_LINK		0x0001
101 #define VTNET_FLAG_SUSPENDED	0x0002
102 #define VTNET_FLAG_CTRL_VQ	0x0004
103 #define VTNET_FLAG_CTRL_RX	0x0008
104 #define VTNET_FLAG_VLAN_FILTER	0x0010
105 #define VTNET_FLAG_TSO_ECN	0x0020
106 #define VTNET_FLAG_MRG_RXBUFS	0x0040
107 #define VTNET_FLAG_LRO_NOMRG	0x0080
108 
109 	struct virtqueue	*vtnet_rx_vq;
110 	struct virtqueue	*vtnet_tx_vq;
111 	struct virtqueue	*vtnet_ctrl_vq;
112 
113 	struct vtnet_tx_header	*vtnet_txhdrarea;
114 	uint32_t		vtnet_txhdridx;
115 	struct vtnet_mac_filter *vtnet_macfilter;
116 
117 	int			vtnet_hdr_size;
118 	int			vtnet_tx_size;
119 	int			vtnet_rx_size;
120 	int			vtnet_rx_process_limit;
121 	int			vtnet_rx_mbuf_size;
122 	int			vtnet_rx_mbuf_count;
123 	int			vtnet_if_flags;
124 	int			vtnet_watchdog_timer;
125 	uint64_t		vtnet_features;
126 
127 	struct task		vtnet_cfgchg_task;
128 
129 	struct vtnet_statistics	vtnet_stats;
130 
131 	struct sysctl_ctx_list  vtnet_sysctl_ctx;
132 	struct sysctl_oid       *vtnet_sysctl_tree;
133 
134 	struct callout		vtnet_tick_ch;
135 
136 	eventhandler_tag	vtnet_vlan_attach;
137 	eventhandler_tag	vtnet_vlan_detach;
138 
139 	struct ifmedia		vtnet_media;
140 	/*
141 	 * Fake media type; the host does not provide us with
142 	 * any real media information.
143 	 */
144 #define VTNET_MEDIATYPE		(IFM_ETHER | IFM_1000_T | IFM_FDX)
145 	char			vtnet_hwaddr[ETHER_ADDR_LEN];
146 
147 	/*
148 	 * During reset, the host's VLAN filtering table is lost. The
149 	 * array below is used to restore all the VLANs configured on
150 	 * this interface after a reset.
151 	 */
152 #define VTNET_VLAN_SHADOW_SIZE	(4096 / 32)
153 	int			vtnet_nvlans;
154 	uint32_t		vtnet_vlan_shadow[VTNET_VLAN_SHADOW_SIZE];
155 
156 	char			vtnet_mtx_name[16];
157 };
158 
159 /*
160  * When mergeable buffers are not negotiated, the vtnet_rx_header structure
161  * below is placed at the beginning of the mbuf data. Use 4 bytes of pad to
162  * both keep the VirtIO header and the data non-contiguous and to keep the
163  * frame's payload 4 byte aligned.
164  *
165  * When mergeable buffers are negotiated, the host puts the VirtIO header in
166  * the beginning of the first mbuf's data.
167  */
168 #define VTNET_RX_HEADER_PAD	4
169 struct vtnet_rx_header {
170 	struct virtio_net_hdr	vrh_hdr;
171 	char			vrh_pad[VTNET_RX_HEADER_PAD];
172 } __packed;
173 
174 /*
175  * For each outgoing frame, the vtnet_tx_header below is allocated from
176  * the vtnet_tx_header_zone.
177  */
178 struct vtnet_tx_header {
179 	union {
180 		struct virtio_net_hdr		hdr;
181 		struct virtio_net_hdr_mrg_rxbuf	mhdr;
182 	} vth_uhdr;
183 
184 	struct mbuf		*vth_mbuf;
185 };
186 
187 MALLOC_DEFINE(M_VTNET, "VTNET_TX", "Outgoing VTNET TX frame header");
188 
189 /*
190  * The VirtIO specification does not place a limit on the number of MAC
191  * addresses the guest driver may request to be filtered. In practice,
192  * the host is constrained by available resources. To simplify this driver,
193  * impose a reasonably high limit of MAC addresses we will filter before
194  * falling back to promiscuous or all-multicast modes.
195  */
196 #define VTNET_MAX_MAC_ENTRIES	128
197 
198 struct vtnet_mac_table {
199 	uint32_t		nentries;
200 	uint8_t			macs[VTNET_MAX_MAC_ENTRIES][ETHER_ADDR_LEN];
201 } __packed;
202 
203 struct vtnet_mac_filter {
204 	struct vtnet_mac_table	vmf_unicast;
205 	uint32_t		vmf_pad; /* Make tables non-contiguous. */
206 	struct vtnet_mac_table	vmf_multicast;
207 };
208 
209 #define VTNET_WATCHDOG_TIMEOUT	5
210 #define VTNET_CSUM_OFFLOAD	(CSUM_TCP | CSUM_UDP)// | CSUM_SCTP)
211 
212 /* Features desired/implemented by this driver. */
213 #define VTNET_FEATURES 		\
214     (VIRTIO_NET_F_MAC		| \
215      VIRTIO_NET_F_STATUS	| \
216      VIRTIO_NET_F_CTRL_VQ	| \
217      VIRTIO_NET_F_CTRL_RX	| \
218      VIRTIO_NET_F_CTRL_VLAN	| \
219      VIRTIO_NET_F_CSUM		| \
220      VIRTIO_NET_F_HOST_TSO4	| \
221      VIRTIO_NET_F_HOST_TSO6	| \
222      VIRTIO_NET_F_HOST_ECN	| \
223      VIRTIO_NET_F_GUEST_CSUM	| \
224      VIRTIO_NET_F_GUEST_TSO4	| \
225      VIRTIO_NET_F_GUEST_TSO6	| \
226      VIRTIO_NET_F_GUEST_ECN	| \
227      VIRTIO_NET_F_MRG_RXBUF)
228 
229 /*
230  * The VIRTIO_NET_F_GUEST_TSO[46] features permit the host to send us
231  * frames larger than 1514 bytes. We do not yet support software LRO
232  * via tcp_lro_rx().
233  */
234 #define VTNET_LRO_FEATURES (VIRTIO_NET_F_GUEST_TSO4 | \
235 			    VIRTIO_NET_F_GUEST_TSO6 | VIRTIO_NET_F_GUEST_ECN)
236 
237 #define VTNET_MAX_MTU		65536
238 #define VTNET_MAX_RX_SIZE	65550
239 
240 /*
241  * Used to preallocate the Vq indirect descriptors. The first segment
242  * is reserved for the header.
243  */
244 #define VTNET_MIN_RX_SEGS	2
245 #define VTNET_MAX_RX_SEGS	34
246 #define VTNET_MAX_TX_SEGS	34
247 
248 #ifndef CSUM_TSO
249 #define CSUM_TSO                0
250 #endif
251 
252 #define IFCAP_TSO4              0x00100 /* can do TCP Segmentation Offload */
253 #define IFCAP_TSO6              0x00200 /* can do TCP6 Segmentation Offload */
254 #define IFCAP_LRO               0x00400 /* can do Large Receive Offload */
255 #define IFCAP_VLAN_HWFILTER     0x10000 /* interface hw can filter vlan tag */
256 #define IFCAP_VLAN_HWTSO        0x40000 /* can do IFCAP_TSO on VLANs */
257 
258 
259 /*
260  * Assert we can receive and transmit the maximum with regular
261  * size clusters.
262  */
263 CTASSERT(((VTNET_MAX_RX_SEGS - 1) * MCLBYTES) >= VTNET_MAX_RX_SIZE);
264 CTASSERT(((VTNET_MAX_TX_SEGS - 1) * MCLBYTES) >= VTNET_MAX_MTU);
265 
266 /*
267  * Determine how many mbufs are in each receive buffer. For LRO without
268  * mergeable descriptors, we must allocate an mbuf chain large enough to
269  * hold both the vtnet_rx_header and the maximum receivable data.
270  */
271 #define VTNET_NEEDED_RX_MBUFS(_sc)					\
272 	((_sc)->vtnet_flags & VTNET_FLAG_LRO_NOMRG) == 0 ? 1 :		\
273 	howmany(sizeof(struct vtnet_rx_header) + VTNET_MAX_RX_SIZE,	\
274 	(_sc)->vtnet_rx_mbuf_size)
275 
276 static int	vtnet_modevent(module_t, int, void *);
277 
278 static int	vtnet_probe(device_t);
279 static int	vtnet_attach(device_t);
280 static int	vtnet_detach(device_t);
281 static int	vtnet_suspend(device_t);
282 static int	vtnet_resume(device_t);
283 static int	vtnet_shutdown(device_t);
284 static int	vtnet_config_change(device_t);
285 
286 static void	vtnet_negotiate_features(struct vtnet_softc *);
287 static int	vtnet_alloc_virtqueues(struct vtnet_softc *);
288 static void	vtnet_get_hwaddr(struct vtnet_softc *);
289 static void	vtnet_set_hwaddr(struct vtnet_softc *);
290 static int	vtnet_is_link_up(struct vtnet_softc *);
291 static void	vtnet_update_link_status(struct vtnet_softc *);
292 #if 0
293 static void	vtnet_watchdog(struct vtnet_softc *);
294 #endif
295 static void	vtnet_config_change_task(void *, int);
296 static int	vtnet_change_mtu(struct vtnet_softc *, int);
297 static int	vtnet_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
298 
299 static int	vtnet_init_rx_vq(struct vtnet_softc *);
300 static void	vtnet_free_rx_mbufs(struct vtnet_softc *);
301 static void	vtnet_free_tx_mbufs(struct vtnet_softc *);
302 static void	vtnet_free_ctrl_vq(struct vtnet_softc *);
303 
304 static struct mbuf * vtnet_alloc_rxbuf(struct vtnet_softc *, int,
305 		    struct mbuf **);
306 static int	vtnet_replace_rxbuf(struct vtnet_softc *,
307 		    struct mbuf *, int);
308 static int	vtnet_newbuf(struct vtnet_softc *);
309 static void	vtnet_discard_merged_rxbuf(struct vtnet_softc *, int);
310 static void	vtnet_discard_rxbuf(struct vtnet_softc *, struct mbuf *);
311 static int	vtnet_enqueue_rxbuf(struct vtnet_softc *, struct mbuf *);
312 static void	vtnet_vlan_tag_remove(struct mbuf *);
313 static int	vtnet_rx_csum(struct vtnet_softc *, struct mbuf *,
314 		    struct virtio_net_hdr *);
315 static int	vtnet_rxeof_merged(struct vtnet_softc *, struct mbuf *, int);
316 static int	vtnet_rxeof(struct vtnet_softc *, int, int *);
317 static void	vtnet_rx_intr_task(void *);
318 static int	vtnet_rx_vq_intr(void *);
319 
320 static void	vtnet_txeof(struct vtnet_softc *);
321 static struct mbuf * vtnet_tx_offload(struct vtnet_softc *, struct mbuf *,
322 		    struct virtio_net_hdr *);
323 static int	vtnet_enqueue_txbuf(struct vtnet_softc *, struct mbuf **,
324 		    struct vtnet_tx_header *);
325 static int	vtnet_encap(struct vtnet_softc *, struct mbuf **);
326 static void	vtnet_start_locked(struct ifnet *, struct ifaltq_subque *);
327 static void	vtnet_start(struct ifnet *, struct ifaltq_subque *);
328 static void	vtnet_tick(void *);
329 static void	vtnet_tx_intr_task(void *);
330 static int	vtnet_tx_vq_intr(void *);
331 
332 static void	vtnet_stop(struct vtnet_softc *);
333 static int	vtnet_reinit(struct vtnet_softc *);
334 static void	vtnet_init_locked(struct vtnet_softc *);
335 static void	vtnet_init(void *);
336 
337 static void	vtnet_exec_ctrl_cmd(struct vtnet_softc *, void *,
338 		    struct sglist *, int, int);
339 
340 static void	vtnet_rx_filter(struct vtnet_softc *sc);
341 static int	vtnet_ctrl_rx_cmd(struct vtnet_softc *, int, int);
342 static int	vtnet_set_promisc(struct vtnet_softc *, int);
343 static int	vtnet_set_allmulti(struct vtnet_softc *, int);
344 static void	vtnet_rx_filter_mac(struct vtnet_softc *);
345 
346 static int	vtnet_exec_vlan_filter(struct vtnet_softc *, int, uint16_t);
347 static void	vtnet_rx_filter_vlan(struct vtnet_softc *);
348 static void	vtnet_set_vlan_filter(struct vtnet_softc *, int, uint16_t);
349 static void	vtnet_register_vlan(void *, struct ifnet *, uint16_t);
350 static void	vtnet_unregister_vlan(void *, struct ifnet *, uint16_t);
351 
352 static int	vtnet_ifmedia_upd(struct ifnet *);
353 static void	vtnet_ifmedia_sts(struct ifnet *, struct ifmediareq *);
354 
355 static void	vtnet_add_statistics(struct vtnet_softc *);
356 
357 static int	vtnet_enable_rx_intr(struct vtnet_softc *);
358 static int	vtnet_enable_tx_intr(struct vtnet_softc *);
359 static void	vtnet_disable_rx_intr(struct vtnet_softc *);
360 static void	vtnet_disable_tx_intr(struct vtnet_softc *);
361 
362 /* Tunables. */
363 static int vtnet_csum_disable = 0;
364 TUNABLE_INT("hw.vtnet.csum_disable", &vtnet_csum_disable);
365 static int vtnet_tso_disable = 1;
366 TUNABLE_INT("hw.vtnet.tso_disable", &vtnet_tso_disable);
367 static int vtnet_lro_disable = 1;
368 TUNABLE_INT("hw.vtnet.lro_disable", &vtnet_lro_disable);
369 
370 /*
371  * Reducing the number of transmit completed interrupts can
372  * improve performance. To do so, the define below keeps the
373  * Tx vq interrupt disabled and adds calls to vtnet_txeof()
374  * in the start and watchdog paths. The price to pay for this
375  * is the m_free'ing of transmitted mbufs may be delayed until
376  * the watchdog fires.
377  */
378 #define VTNET_TX_INTR_MODERATION
379 
380 static struct virtio_feature_desc vtnet_feature_desc[] = {
381 	{ VIRTIO_NET_F_CSUM,		"TxChecksum"	},
382 	{ VIRTIO_NET_F_GUEST_CSUM,	"RxChecksum"	},
383 	{ VIRTIO_NET_F_MAC,		"MacAddress"	},
384 	{ VIRTIO_NET_F_GSO,		"TxAllGSO"	},
385 	{ VIRTIO_NET_F_GUEST_TSO4,	"RxTSOv4"	},
386 	{ VIRTIO_NET_F_GUEST_TSO6,	"RxTSOv6"	},
387 	{ VIRTIO_NET_F_GUEST_ECN,	"RxECN"		},
388 	{ VIRTIO_NET_F_GUEST_UFO,	"RxUFO"		},
389 	{ VIRTIO_NET_F_HOST_TSO4,	"TxTSOv4"	},
390 	{ VIRTIO_NET_F_HOST_TSO6,	"TxTSOv6"	},
391 	{ VIRTIO_NET_F_HOST_ECN,	"TxTSOECN"	},
392 	{ VIRTIO_NET_F_HOST_UFO,	"TxUFO"		},
393 	{ VIRTIO_NET_F_MRG_RXBUF,	"MrgRxBuf"	},
394 	{ VIRTIO_NET_F_STATUS,		"Status"	},
395 	{ VIRTIO_NET_F_CTRL_VQ,		"ControlVq"	},
396 	{ VIRTIO_NET_F_CTRL_RX,		"RxMode"	},
397 	{ VIRTIO_NET_F_CTRL_VLAN,	"VLanFilter"	},
398 	{ VIRTIO_NET_F_CTRL_RX_EXTRA,	"RxModeExtra"	},
399 	{ VIRTIO_NET_F_MQ,		"RFS"		},
400 	{ 0, NULL }
401 };
402 
403 static device_method_t vtnet_methods[] = {
404 	/* Device methods. */
405 	DEVMETHOD(device_probe,		vtnet_probe),
406 	DEVMETHOD(device_attach,	vtnet_attach),
407 	DEVMETHOD(device_detach,	vtnet_detach),
408 	DEVMETHOD(device_suspend,	vtnet_suspend),
409 	DEVMETHOD(device_resume,	vtnet_resume),
410 	DEVMETHOD(device_shutdown,	vtnet_shutdown),
411 
412 	/* VirtIO methods. */
413 	DEVMETHOD(virtio_config_change, vtnet_config_change),
414 
415 	{ 0, 0 }
416 };
417 
418 static driver_t vtnet_driver = {
419 	"vtnet",
420 	vtnet_methods,
421 	sizeof(struct vtnet_softc)
422 };
423 
424 static devclass_t vtnet_devclass;
425 
426 DRIVER_MODULE(vtnet, virtio_pci, vtnet_driver, vtnet_devclass,
427 	      vtnet_modevent, 0);
428 MODULE_VERSION(vtnet, 1);
429 MODULE_DEPEND(vtnet, virtio, 1, 1, 1);
430 
431 static int
432 vtnet_modevent(module_t mod, int type, void *unused)
433 {
434 	int error;
435 
436 	error = 0;
437 
438 	switch (type) {
439 	case MOD_LOAD:
440 		break;
441 	case MOD_UNLOAD:
442 		break;
443 	case MOD_SHUTDOWN:
444 		break;
445 	default:
446 		error = EOPNOTSUPP;
447 		break;
448 	}
449 
450 	return (error);
451 }
452 
453 static int
454 vtnet_probe(device_t dev)
455 {
456 	if (virtio_get_device_type(dev) != VIRTIO_ID_NETWORK)
457 		return (ENXIO);
458 
459 	device_set_desc(dev, "VirtIO Networking Adapter");
460 
461 	return (BUS_PROBE_DEFAULT);
462 }
463 
464 static int
465 vtnet_attach(device_t dev)
466 {
467 	struct vtnet_softc *sc;
468 	struct ifnet *ifp;
469 	int tx_size, error;
470 
471 	sc = device_get_softc(dev);
472 	sc->vtnet_dev = dev;
473 
474 	lwkt_serialize_init(&sc->vtnet_slz);
475 	callout_init(&sc->vtnet_tick_ch);
476 
477 	ifmedia_init(&sc->vtnet_media, IFM_IMASK, vtnet_ifmedia_upd,
478 		     vtnet_ifmedia_sts);
479 	ifmedia_add(&sc->vtnet_media, VTNET_MEDIATYPE, 0, NULL);
480 	ifmedia_set(&sc->vtnet_media, VTNET_MEDIATYPE);
481 
482 	vtnet_add_statistics(sc);
483 
484 	virtio_set_feature_desc(dev, vtnet_feature_desc);
485 	vtnet_negotiate_features(sc);
486 
487 	if (virtio_with_feature(dev, VIRTIO_NET_F_MRG_RXBUF)) {
488 		sc->vtnet_flags |= VTNET_FLAG_MRG_RXBUFS;
489 		sc->vtnet_hdr_size = sizeof(struct virtio_net_hdr_mrg_rxbuf);
490 	} else {
491 		sc->vtnet_hdr_size = sizeof(struct virtio_net_hdr);
492 	}
493 
494 	sc->vtnet_rx_mbuf_size = MCLBYTES;
495 	sc->vtnet_rx_mbuf_count = VTNET_NEEDED_RX_MBUFS(sc);
496 
497 	if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_VQ)) {
498 		sc->vtnet_flags |= VTNET_FLAG_CTRL_VQ;
499 
500 		if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_RX))
501 			sc->vtnet_flags |= VTNET_FLAG_CTRL_RX;
502 		if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_VLAN))
503 			sc->vtnet_flags |= VTNET_FLAG_VLAN_FILTER;
504 	}
505 
506 	vtnet_get_hwaddr(sc);
507 
508 	error = vtnet_alloc_virtqueues(sc);
509 	if (error) {
510 		device_printf(dev, "cannot allocate virtqueues\n");
511 		goto fail;
512 	}
513 
514 	ifp = sc->vtnet_ifp = if_alloc(IFT_ETHER);
515 	if (ifp == NULL) {
516 		device_printf(dev, "cannot allocate ifnet structure\n");
517 		error = ENOSPC;
518 		goto fail;
519 	}
520 
521 	ifp->if_softc = sc;
522 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
523 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
524 	ifp->if_init = vtnet_init;
525 	ifp->if_start = vtnet_start;
526 	ifp->if_ioctl = vtnet_ioctl;
527 
528 	sc->vtnet_rx_size = virtqueue_size(sc->vtnet_rx_vq);
529 	sc->vtnet_rx_process_limit = sc->vtnet_rx_size;
530 
531 	tx_size = virtqueue_size(sc->vtnet_tx_vq);
532 	sc->vtnet_tx_size = tx_size;
533 	sc->vtnet_txhdridx = 0;
534 	sc->vtnet_txhdrarea = contigmalloc(
535 	    ((sc->vtnet_tx_size / 2) + 1) * sizeof(struct vtnet_tx_header),
536 	    M_VTNET, M_WAITOK, 0, BUS_SPACE_MAXADDR, 4, 0);
537 	if (sc->vtnet_txhdrarea == NULL) {
538 		device_printf(dev, "cannot contigmalloc the tx headers\n");
539 		goto fail;
540 	}
541 	sc->vtnet_macfilter = contigmalloc(
542 	    sizeof(struct vtnet_mac_filter),
543 	    M_DEVBUF, M_WAITOK, 0, BUS_SPACE_MAXADDR, 4, 0);
544 	if (sc->vtnet_macfilter == NULL) {
545 		device_printf(dev,
546 		    "cannot contigmalloc the mac filter table\n");
547 		goto fail;
548 	}
549 	ifq_set_maxlen(&ifp->if_snd, tx_size - 1);
550 	ifq_set_ready(&ifp->if_snd);
551 
552 	ether_ifattach(ifp, sc->vtnet_hwaddr, NULL);
553 
554 	if (virtio_with_feature(dev, VIRTIO_NET_F_STATUS)){
555 		//ifp->if_capabilities |= IFCAP_LINKSTATE;
556 		 kprintf("add dynamic link state\n");
557 	}
558 
559 	/* Tell the upper layer(s) we support long frames. */
560 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
561 	ifp->if_capabilities |= IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU;
562 
563 	if (virtio_with_feature(dev, VIRTIO_NET_F_CSUM)) {
564 		ifp->if_capabilities |= IFCAP_TXCSUM;
565 
566 		if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_TSO4))
567 			ifp->if_capabilities |= IFCAP_TSO4;
568 		if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_TSO6))
569 			ifp->if_capabilities |= IFCAP_TSO6;
570 		if (ifp->if_capabilities & IFCAP_TSO)
571 			ifp->if_capabilities |= IFCAP_VLAN_HWTSO;
572 
573 		if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_ECN))
574 			sc->vtnet_flags |= VTNET_FLAG_TSO_ECN;
575 	}
576 
577 	if (virtio_with_feature(dev, VIRTIO_NET_F_GUEST_CSUM)) {
578 		ifp->if_capabilities |= IFCAP_RXCSUM;
579 
580 		if (virtio_with_feature(dev, VIRTIO_NET_F_GUEST_TSO4) ||
581 		    virtio_with_feature(dev, VIRTIO_NET_F_GUEST_TSO6))
582 			ifp->if_capabilities |= IFCAP_LRO;
583 	}
584 
585 	if (ifp->if_capabilities & IFCAP_HWCSUM) {
586 		/*
587 		 * VirtIO does not support VLAN tagging, but we can fake
588 		 * it by inserting and removing the 802.1Q header during
589 		 * transmit and receive. We are then able to do checksum
590 		 * offloading of VLAN frames.
591 		 */
592 		ifp->if_capabilities |=
593 			IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_HWCSUM;
594 	}
595 
596 	ifp->if_capenable = ifp->if_capabilities;
597 
598 	/*
599 	 * Capabilities after here are not enabled by default.
600 	 */
601 
602 	if (sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER) {
603 		ifp->if_capabilities |= IFCAP_VLAN_HWFILTER;
604 
605 		sc->vtnet_vlan_attach = EVENTHANDLER_REGISTER(vlan_config,
606 		    vtnet_register_vlan, sc, EVENTHANDLER_PRI_FIRST);
607 		sc->vtnet_vlan_detach = EVENTHANDLER_REGISTER(vlan_unconfig,
608 		    vtnet_unregister_vlan, sc, EVENTHANDLER_PRI_FIRST);
609 	}
610 
611 	TASK_INIT(&sc->vtnet_cfgchg_task, 0, vtnet_config_change_task, sc);
612 
613 	error = virtio_setup_intr(dev, &sc->vtnet_slz);
614 	if (error) {
615 		device_printf(dev, "cannot setup virtqueue interrupts\n");
616 		ether_ifdetach(ifp);
617 		goto fail;
618 	}
619 
620 	/*
621 	 * Device defaults to promiscuous mode for backwards
622 	 * compatibility. Turn it off if possible.
623 	 */
624 	if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX) {
625 		lwkt_serialize_enter(&sc->vtnet_slz);
626 		if (vtnet_set_promisc(sc, 0) != 0) {
627 			ifp->if_flags |= IFF_PROMISC;
628 			device_printf(dev,
629 			    "cannot disable promiscuous mode\n");
630 		}
631 		lwkt_serialize_exit(&sc->vtnet_slz);
632 	} else
633 		ifp->if_flags |= IFF_PROMISC;
634 
635 fail:
636 	if (error)
637 		vtnet_detach(dev);
638 
639 	return (error);
640 }
641 
642 static int
643 vtnet_detach(device_t dev)
644 {
645 	struct vtnet_softc *sc;
646 	struct ifnet *ifp;
647 
648 	sc = device_get_softc(dev);
649 	ifp = sc->vtnet_ifp;
650 
651 	if (device_is_attached(dev)) {
652 		lwkt_serialize_enter(&sc->vtnet_slz);
653 		vtnet_stop(sc);
654 		lwkt_serialize_exit(&sc->vtnet_slz);
655 
656 		callout_stop(&sc->vtnet_tick_ch);
657 		taskqueue_drain(taskqueue_swi, &sc->vtnet_cfgchg_task);
658 
659 		ether_ifdetach(ifp);
660 	}
661 
662 	if (sc->vtnet_vlan_attach != NULL) {
663 		EVENTHANDLER_DEREGISTER(vlan_config, sc->vtnet_vlan_attach);
664 		sc->vtnet_vlan_attach = NULL;
665 	}
666 	if (sc->vtnet_vlan_detach != NULL) {
667 		EVENTHANDLER_DEREGISTER(vlan_unconfg, sc->vtnet_vlan_detach);
668 		sc->vtnet_vlan_detach = NULL;
669 	}
670 
671 	if (ifp) {
672 		if_free(ifp);
673 		sc->vtnet_ifp = NULL;
674 	}
675 
676 	if (sc->vtnet_rx_vq != NULL)
677 		vtnet_free_rx_mbufs(sc);
678 	if (sc->vtnet_tx_vq != NULL)
679 		vtnet_free_tx_mbufs(sc);
680 	if (sc->vtnet_ctrl_vq != NULL)
681 		vtnet_free_ctrl_vq(sc);
682 
683 	if (sc->vtnet_txhdrarea != NULL) {
684 		contigfree(sc->vtnet_txhdrarea,
685 		    ((sc->vtnet_tx_size / 2) + 1) *
686 		    sizeof(struct vtnet_tx_header), M_VTNET);
687 		sc->vtnet_txhdrarea = NULL;
688 	}
689 	if (sc->vtnet_macfilter != NULL) {
690 		contigfree(sc->vtnet_macfilter,
691 		    sizeof(struct vtnet_mac_filter), M_DEVBUF);
692 		sc->vtnet_macfilter = NULL;
693 	}
694 
695 	ifmedia_removeall(&sc->vtnet_media);
696 
697 	return (0);
698 }
699 
700 static int
701 vtnet_suspend(device_t dev)
702 {
703 	struct vtnet_softc *sc;
704 
705 	sc = device_get_softc(dev);
706 
707 	lwkt_serialize_enter(&sc->vtnet_slz);
708 	vtnet_stop(sc);
709 	sc->vtnet_flags |= VTNET_FLAG_SUSPENDED;
710 	lwkt_serialize_exit(&sc->vtnet_slz);
711 
712 	return (0);
713 }
714 
715 static int
716 vtnet_resume(device_t dev)
717 {
718 	struct vtnet_softc *sc;
719 	struct ifnet *ifp;
720 
721 	sc = device_get_softc(dev);
722 	ifp = sc->vtnet_ifp;
723 
724 	lwkt_serialize_enter(&sc->vtnet_slz);
725 	if (ifp->if_flags & IFF_UP)
726 		vtnet_init_locked(sc);
727 	sc->vtnet_flags &= ~VTNET_FLAG_SUSPENDED;
728 	lwkt_serialize_exit(&sc->vtnet_slz);
729 
730 	return (0);
731 }
732 
733 static int
734 vtnet_shutdown(device_t dev)
735 {
736 
737 	/*
738 	 * Suspend already does all of what we need to
739 	 * do here; we just never expect to be resumed.
740 	 */
741 	return (vtnet_suspend(dev));
742 }
743 
744 static int
745 vtnet_config_change(device_t dev)
746 {
747 	struct vtnet_softc *sc;
748 
749 	sc = device_get_softc(dev);
750 
751 	taskqueue_enqueue(taskqueue_thread[mycpuid], &sc->vtnet_cfgchg_task);
752 
753 	return (1);
754 }
755 
756 static void
757 vtnet_negotiate_features(struct vtnet_softc *sc)
758 {
759 	device_t dev;
760 	uint64_t mask, features;
761 
762 	dev = sc->vtnet_dev;
763 	mask = 0;
764 
765 	if (vtnet_csum_disable)
766 		mask |= VIRTIO_NET_F_CSUM | VIRTIO_NET_F_GUEST_CSUM;
767 
768 	/*
769 	 * TSO and LRO are only available when their corresponding
770 	 * checksum offload feature is also negotiated.
771 	 */
772 
773 	if (vtnet_csum_disable || vtnet_tso_disable)
774 		mask |= VIRTIO_NET_F_HOST_TSO4 | VIRTIO_NET_F_HOST_TSO6 |
775 		    VIRTIO_NET_F_HOST_ECN;
776 
777 	if (vtnet_csum_disable || vtnet_lro_disable)
778 		mask |= VTNET_LRO_FEATURES;
779 
780 	features = VTNET_FEATURES & ~mask;
781 	features |= VIRTIO_F_NOTIFY_ON_EMPTY;
782 	sc->vtnet_features = virtio_negotiate_features(dev, features);
783 }
784 
785 static int
786 vtnet_alloc_virtqueues(struct vtnet_softc *sc)
787 {
788 	device_t dev;
789 	struct vq_alloc_info vq_info[3];
790 	int nvqs, rxsegs;
791 
792 	dev = sc->vtnet_dev;
793 	nvqs = 2;
794 
795 	/*
796 	 * Indirect descriptors are not needed for the Rx
797 	 * virtqueue when mergeable buffers are negotiated.
798 	 * The header is placed inline with the data, not
799 	 * in a separate descriptor, and mbuf clusters are
800 	 * always physically contiguous.
801 	 */
802 	if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
803 		rxsegs = sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG ?
804 		    VTNET_MAX_RX_SEGS : VTNET_MIN_RX_SEGS;
805 	} else
806 		rxsegs = 0;
807 
808 	VQ_ALLOC_INFO_INIT(&vq_info[0], rxsegs,
809 	    vtnet_rx_vq_intr, sc, &sc->vtnet_rx_vq,
810 	    "%s receive", device_get_nameunit(dev));
811 
812 	VQ_ALLOC_INFO_INIT(&vq_info[1], VTNET_MAX_TX_SEGS,
813 	    vtnet_tx_vq_intr, sc, &sc->vtnet_tx_vq,
814 	    "%s transmit", device_get_nameunit(dev));
815 
816 	if (sc->vtnet_flags & VTNET_FLAG_CTRL_VQ) {
817 		nvqs++;
818 
819 		VQ_ALLOC_INFO_INIT(&vq_info[2], 0, NULL, NULL,
820 		    &sc->vtnet_ctrl_vq, "%s control",
821 		    device_get_nameunit(dev));
822 	}
823 
824 	return (virtio_alloc_virtqueues(dev, 0, nvqs, vq_info));
825 }
826 
827 static void
828 vtnet_get_hwaddr(struct vtnet_softc *sc)
829 {
830 	device_t dev;
831 
832 	dev = sc->vtnet_dev;
833 
834 	if (virtio_with_feature(dev, VIRTIO_NET_F_MAC)) {
835 		virtio_read_device_config(dev,
836 		    offsetof(struct virtio_net_config, mac),
837 		    sc->vtnet_hwaddr, ETHER_ADDR_LEN);
838 	} else {
839 		/* Generate random locally administered unicast address. */
840 		sc->vtnet_hwaddr[0] = 0xB2;
841 		karc4rand(&sc->vtnet_hwaddr[1], ETHER_ADDR_LEN - 1);
842 
843 		vtnet_set_hwaddr(sc);
844 	}
845 }
846 
847 static void
848 vtnet_set_hwaddr(struct vtnet_softc *sc)
849 {
850 	device_t dev;
851 
852 	dev = sc->vtnet_dev;
853 
854 	virtio_write_device_config(dev,
855 	    offsetof(struct virtio_net_config, mac),
856 	    sc->vtnet_hwaddr, ETHER_ADDR_LEN);
857 }
858 
859 static int
860 vtnet_is_link_up(struct vtnet_softc *sc)
861 {
862 	device_t dev;
863 	struct ifnet *ifp;
864 	uint16_t status;
865 
866 	dev = sc->vtnet_dev;
867 	ifp = sc->vtnet_ifp;
868 
869 	ASSERT_SERIALIZED(&sc->vtnet_slz);
870 
871 	status = virtio_read_dev_config_2(dev,
872 			offsetof(struct virtio_net_config, status));
873 
874 	return ((status & VIRTIO_NET_S_LINK_UP) != 0);
875 }
876 
877 static void
878 vtnet_update_link_status(struct vtnet_softc *sc)
879 {
880 	device_t dev;
881 	struct ifnet *ifp;
882 	struct ifaltq_subque *ifsq;
883 	int link;
884 
885 	dev = sc->vtnet_dev;
886 	ifp = sc->vtnet_ifp;
887 	ifsq = ifq_get_subq_default(&ifp->if_snd);
888 
889 	link = vtnet_is_link_up(sc);
890 
891 	if (link && ((sc->vtnet_flags & VTNET_FLAG_LINK) == 0)) {
892 		sc->vtnet_flags |= VTNET_FLAG_LINK;
893 		if (bootverbose)
894 			device_printf(dev, "Link is up\n");
895 		ifp->if_link_state = LINK_STATE_UP;
896 		if_link_state_change(ifp);
897 		if (!ifsq_is_empty(ifsq))
898 			vtnet_start_locked(ifp, ifsq);
899 	} else if (!link && (sc->vtnet_flags & VTNET_FLAG_LINK)) {
900 		sc->vtnet_flags &= ~VTNET_FLAG_LINK;
901 		if (bootverbose)
902 			device_printf(dev, "Link is down\n");
903 
904 		ifp->if_link_state = LINK_STATE_DOWN;
905 		if_link_state_change(ifp);
906 	}
907 }
908 
909 #if 0
910 static void
911 vtnet_watchdog(struct vtnet_softc *sc)
912 {
913 	struct ifnet *ifp;
914 
915 	ifp = sc->vtnet_ifp;
916 
917 #ifdef VTNET_TX_INTR_MODERATION
918 	vtnet_txeof(sc);
919 #endif
920 
921 	if (sc->vtnet_watchdog_timer == 0 || --sc->vtnet_watchdog_timer)
922 		return;
923 
924 	if_printf(ifp, "watchdog timeout -- resetting\n");
925 #ifdef VTNET_DEBUG
926 	virtqueue_dump(sc->vtnet_tx_vq);
927 #endif
928 	ifp->if_oerrors++;
929 	ifp->if_flags &= ~IFF_RUNNING;
930 	vtnet_init_locked(sc);
931 }
932 #endif
933 
934 static void
935 vtnet_config_change_task(void *arg, int pending)
936 {
937 	struct vtnet_softc *sc;
938 
939 	sc = arg;
940 
941 	lwkt_serialize_enter(&sc->vtnet_slz);
942 	vtnet_update_link_status(sc);
943 	lwkt_serialize_exit(&sc->vtnet_slz);
944 }
945 
946 static int
947 vtnet_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data,struct ucred *cr)
948 {
949 	struct vtnet_softc *sc;
950 	struct ifreq *ifr;
951 	int reinit, mask, error;
952 
953 	sc = ifp->if_softc;
954 	ifr = (struct ifreq *) data;
955 	reinit = 0;
956 	error = 0;
957 
958 	switch (cmd) {
959 	case SIOCSIFMTU:
960 		if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > VTNET_MAX_MTU)
961 			error = EINVAL;
962 		else if (ifp->if_mtu != ifr->ifr_mtu) {
963 			lwkt_serialize_enter(&sc->vtnet_slz);
964 			error = vtnet_change_mtu(sc, ifr->ifr_mtu);
965 			lwkt_serialize_exit(&sc->vtnet_slz);
966 		}
967 		break;
968 
969 	case SIOCSIFFLAGS:
970 		lwkt_serialize_enter(&sc->vtnet_slz);
971 		if ((ifp->if_flags & IFF_UP) == 0) {
972 			if (ifp->if_flags & IFF_RUNNING)
973 				vtnet_stop(sc);
974 		} else if (ifp->if_flags & IFF_RUNNING) {
975 			if ((ifp->if_flags ^ sc->vtnet_if_flags) &
976 			    (IFF_PROMISC | IFF_ALLMULTI)) {
977 				if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX)
978 					vtnet_rx_filter(sc);
979 				else
980 					error = ENOTSUP;
981 			}
982 		} else
983 			vtnet_init_locked(sc);
984 
985 		if (error == 0)
986 			sc->vtnet_if_flags = ifp->if_flags;
987 		lwkt_serialize_exit(&sc->vtnet_slz);
988 		break;
989 
990 	case SIOCADDMULTI:
991 	case SIOCDELMULTI:
992 		lwkt_serialize_enter(&sc->vtnet_slz);
993 		if ((sc->vtnet_flags & VTNET_FLAG_CTRL_RX) &&
994 		    (ifp->if_flags & IFF_RUNNING))
995 			vtnet_rx_filter_mac(sc);
996 		lwkt_serialize_exit(&sc->vtnet_slz);
997 		break;
998 
999 	case SIOCSIFMEDIA:
1000 	case SIOCGIFMEDIA:
1001 		error = ifmedia_ioctl(ifp, ifr, &sc->vtnet_media, cmd);
1002 		break;
1003 
1004 	case SIOCSIFCAP:
1005 		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
1006 
1007 		lwkt_serialize_enter(&sc->vtnet_slz);
1008 
1009 		if (mask & IFCAP_TXCSUM) {
1010 			ifp->if_capenable ^= IFCAP_TXCSUM;
1011 			if (ifp->if_capenable & IFCAP_TXCSUM)
1012 				ifp->if_hwassist |= VTNET_CSUM_OFFLOAD;
1013 			else
1014 				ifp->if_hwassist &= ~VTNET_CSUM_OFFLOAD;
1015 		}
1016 
1017 		if (mask & IFCAP_TSO4) {
1018 			ifp->if_capenable ^= IFCAP_TSO4;
1019 			if (ifp->if_capenable & IFCAP_TSO4)
1020 				ifp->if_hwassist |= CSUM_TSO;
1021 			else
1022 				ifp->if_hwassist &= ~CSUM_TSO;
1023 		}
1024 
1025 		if (mask & IFCAP_RXCSUM) {
1026 			ifp->if_capenable ^= IFCAP_RXCSUM;
1027 			reinit = 1;
1028 		}
1029 
1030 		if (mask & IFCAP_LRO) {
1031 			ifp->if_capenable ^= IFCAP_LRO;
1032 			reinit = 1;
1033 		}
1034 
1035 		if (mask & IFCAP_VLAN_HWFILTER) {
1036 			ifp->if_capenable ^= IFCAP_VLAN_HWFILTER;
1037 			reinit = 1;
1038 		}
1039 
1040 		if (mask & IFCAP_VLAN_HWTSO)
1041 			ifp->if_capenable ^= IFCAP_VLAN_HWTSO;
1042 
1043 		if (mask & IFCAP_VLAN_HWTAGGING)
1044 			ifp->if_capenable ^= IFCAP_VLAN_HWTAGGING;
1045 
1046 		if (reinit && (ifp->if_flags & IFF_RUNNING)) {
1047 			ifp->if_flags &= ~IFF_RUNNING;
1048 			vtnet_init_locked(sc);
1049 		}
1050 		//VLAN_CAPABILITIES(ifp);
1051 
1052 		lwkt_serialize_exit(&sc->vtnet_slz);
1053 		break;
1054 
1055 	default:
1056 		error = ether_ioctl(ifp, cmd, data);
1057 		break;
1058 	}
1059 
1060 	return (error);
1061 }
1062 
1063 static int
1064 vtnet_change_mtu(struct vtnet_softc *sc, int new_mtu)
1065 {
1066 	struct ifnet *ifp;
1067 	int new_frame_size, clsize;
1068 
1069 	ifp = sc->vtnet_ifp;
1070 
1071 	if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
1072 		new_frame_size = sizeof(struct vtnet_rx_header) +
1073 		    sizeof(struct ether_vlan_header) + new_mtu;
1074 
1075 		if (new_frame_size > MJUM9BYTES)
1076 			return (EINVAL);
1077 
1078 		if (new_frame_size <= MCLBYTES)
1079 			clsize = MCLBYTES;
1080 		else
1081 			clsize = MJUM9BYTES;
1082 	} else {
1083 		new_frame_size = sizeof(struct virtio_net_hdr_mrg_rxbuf) +
1084 		    sizeof(struct ether_vlan_header) + new_mtu;
1085 
1086 		if (new_frame_size <= MCLBYTES)
1087 			clsize = MCLBYTES;
1088 		else
1089 			clsize = MJUMPAGESIZE;
1090 	}
1091 
1092 	sc->vtnet_rx_mbuf_size = clsize;
1093 	sc->vtnet_rx_mbuf_count = VTNET_NEEDED_RX_MBUFS(sc);
1094 	KASSERT(sc->vtnet_rx_mbuf_count < VTNET_MAX_RX_SEGS,
1095 	    ("too many rx mbufs: %d", sc->vtnet_rx_mbuf_count));
1096 
1097 	ifp->if_mtu = new_mtu;
1098 
1099 	if (ifp->if_flags & IFF_RUNNING) {
1100 		ifp->if_flags &= ~IFF_RUNNING;
1101 		vtnet_init_locked(sc);
1102 	}
1103 
1104 	return (0);
1105 }
1106 
1107 static int
1108 vtnet_init_rx_vq(struct vtnet_softc *sc)
1109 {
1110 	struct virtqueue *vq;
1111 	int nbufs, error;
1112 
1113 	vq = sc->vtnet_rx_vq;
1114 	nbufs = 0;
1115 	error = ENOSPC;
1116 
1117 	while (!virtqueue_full(vq)) {
1118 		if ((error = vtnet_newbuf(sc)) != 0)
1119 			break;
1120 		nbufs++;
1121 	}
1122 
1123 	if (nbufs > 0) {
1124 		virtqueue_notify(vq, &sc->vtnet_slz);
1125 
1126 		/*
1127 		 * EMSGSIZE signifies the virtqueue did not have enough
1128 		 * entries available to hold the last mbuf. This is not
1129 		 * an error. We should not get ENOSPC since we check if
1130 		 * the virtqueue is full before attempting to add a
1131 		 * buffer.
1132 		 */
1133 		if (error == EMSGSIZE)
1134 			error = 0;
1135 	}
1136 
1137 	return (error);
1138 }
1139 
1140 static void
1141 vtnet_free_rx_mbufs(struct vtnet_softc *sc)
1142 {
1143 	struct virtqueue *vq;
1144 	struct mbuf *m;
1145 	int last;
1146 
1147 	vq = sc->vtnet_rx_vq;
1148 	last = 0;
1149 
1150 	while ((m = virtqueue_drain(vq, &last)) != NULL)
1151 		m_freem(m);
1152 
1153 	KASSERT(virtqueue_empty(vq), ("mbufs remaining in Rx Vq"));
1154 }
1155 
1156 static void
1157 vtnet_free_tx_mbufs(struct vtnet_softc *sc)
1158 {
1159 	struct virtqueue *vq;
1160 	struct vtnet_tx_header *txhdr;
1161 	int last;
1162 
1163 	vq = sc->vtnet_tx_vq;
1164 	last = 0;
1165 
1166 	while ((txhdr = virtqueue_drain(vq, &last)) != NULL) {
1167 		m_freem(txhdr->vth_mbuf);
1168 	}
1169 
1170 	KASSERT(virtqueue_empty(vq), ("mbufs remaining in Tx Vq"));
1171 }
1172 
1173 static void
1174 vtnet_free_ctrl_vq(struct vtnet_softc *sc)
1175 {
1176 	/*
1177 	 * The control virtqueue is only polled, therefore
1178 	 * it should already be empty.
1179 	 */
1180 	KASSERT(virtqueue_empty(sc->vtnet_ctrl_vq),
1181 		("Ctrl Vq not empty"));
1182 }
1183 
1184 static struct mbuf *
1185 vtnet_alloc_rxbuf(struct vtnet_softc *sc, int nbufs, struct mbuf **m_tailp)
1186 {
1187 	struct mbuf *m_head, *m_tail, *m;
1188 	int i, clsize;
1189 
1190 	clsize = sc->vtnet_rx_mbuf_size;
1191 
1192 	/*use getcl instead of getjcl. see  if_mxge.c comment line 2398*/
1193 	//m_head = m_getjcl(M_DONTWAIT, MT_DATA, M_PKTHDR, clsize);
1194 	m_head = m_getcl(MB_DONTWAIT, MT_DATA, M_PKTHDR );
1195 	if (m_head == NULL)
1196 		goto fail;
1197 
1198 	m_head->m_len = clsize;
1199 	m_tail = m_head;
1200 
1201 	if (nbufs > 1) {
1202 		KASSERT(sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG,
1203 			("chained Rx mbuf requested without LRO_NOMRG"));
1204 
1205 		for (i = 0; i < nbufs - 1; i++) {
1206 			//m = m_getjcl(M_DONTWAIT, MT_DATA, 0, clsize);
1207 			m = m_getcl(MB_DONTWAIT, MT_DATA, 0);
1208 			if (m == NULL)
1209 				goto fail;
1210 
1211 			m->m_len = clsize;
1212 			m_tail->m_next = m;
1213 			m_tail = m;
1214 		}
1215 	}
1216 
1217 	if (m_tailp != NULL)
1218 		*m_tailp = m_tail;
1219 
1220 	return (m_head);
1221 
1222 fail:
1223 	sc->vtnet_stats.mbuf_alloc_failed++;
1224 	m_freem(m_head);
1225 
1226 	return (NULL);
1227 }
1228 
1229 static int
1230 vtnet_replace_rxbuf(struct vtnet_softc *sc, struct mbuf *m0, int len0)
1231 {
1232 	struct mbuf *m, *m_prev;
1233 	struct mbuf *m_new, *m_tail;
1234 	int len, clsize, nreplace, error;
1235 
1236 	m = m0;
1237 	m_prev = NULL;
1238 	len = len0;
1239 
1240 	m_tail = NULL;
1241 	clsize = sc->vtnet_rx_mbuf_size;
1242 	nreplace = 0;
1243 
1244 	if (m->m_next != NULL)
1245 		KASSERT(sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG,
1246 		    ("chained Rx mbuf without LRO_NOMRG"));
1247 
1248 	/*
1249 	 * Since LRO_NOMRG mbuf chains are so large, we want to avoid
1250 	 * allocating an entire chain for each received frame. When
1251 	 * the received frame's length is less than that of the chain,
1252 	 * the unused mbufs are reassigned to the new chain.
1253 	 */
1254 	while (len > 0) {
1255 		/*
1256 		 * Something is seriously wrong if we received
1257 		 * a frame larger than the mbuf chain. Drop it.
1258 		 */
1259 		if (m == NULL) {
1260 			sc->vtnet_stats.rx_frame_too_large++;
1261 			return (EMSGSIZE);
1262 		}
1263 
1264 		KASSERT(m->m_len == clsize,
1265 		    ("mbuf length not expected cluster size: %d",
1266 		    m->m_len));
1267 
1268 		m->m_len = MIN(m->m_len, len);
1269 		len -= m->m_len;
1270 
1271 		m_prev = m;
1272 		m = m->m_next;
1273 		nreplace++;
1274 	}
1275 
1276 	KASSERT(m_prev != NULL, ("m_prev == NULL"));
1277 	KASSERT(nreplace <= sc->vtnet_rx_mbuf_count,
1278 		("too many replacement mbufs: %d/%d", nreplace,
1279 		sc->vtnet_rx_mbuf_count));
1280 
1281 	m_new = vtnet_alloc_rxbuf(sc, nreplace, &m_tail);
1282 	if (m_new == NULL) {
1283 		m_prev->m_len = clsize;
1284 		return (ENOBUFS);
1285 	}
1286 
1287 	/*
1288 	 * Move unused mbufs, if any, from the original chain
1289 	 * onto the end of the new chain.
1290 	 */
1291 	if (m_prev->m_next != NULL) {
1292 		m_tail->m_next = m_prev->m_next;
1293 		m_prev->m_next = NULL;
1294 	}
1295 
1296 	error = vtnet_enqueue_rxbuf(sc, m_new);
1297 	if (error) {
1298 		/*
1299 		 * BAD! We could not enqueue the replacement mbuf chain. We
1300 		 * must restore the m0 chain to the original state if it was
1301 		 * modified so we can subsequently discard it.
1302 		 *
1303 		 * NOTE: The replacement is suppose to be an identical copy
1304 		 * to the one just dequeued so this is an unexpected error.
1305 		 */
1306 		sc->vtnet_stats.rx_enq_replacement_failed++;
1307 
1308 		if (m_tail->m_next != NULL) {
1309 			m_prev->m_next = m_tail->m_next;
1310 			m_tail->m_next = NULL;
1311 		}
1312 
1313 		m_prev->m_len = clsize;
1314 		m_freem(m_new);
1315 	}
1316 
1317 	return (error);
1318 }
1319 
1320 static int
1321 vtnet_newbuf(struct vtnet_softc *sc)
1322 {
1323 	struct mbuf *m;
1324 	int error;
1325 
1326 	m = vtnet_alloc_rxbuf(sc, sc->vtnet_rx_mbuf_count, NULL);
1327 	if (m == NULL)
1328 		return (ENOBUFS);
1329 
1330 	error = vtnet_enqueue_rxbuf(sc, m);
1331 	if (error)
1332 		m_freem(m);
1333 
1334 	return (error);
1335 }
1336 
1337 static void
1338 vtnet_discard_merged_rxbuf(struct vtnet_softc *sc, int nbufs)
1339 {
1340 	struct virtqueue *vq;
1341 	struct mbuf *m;
1342 
1343 	vq = sc->vtnet_rx_vq;
1344 
1345 	while (--nbufs > 0) {
1346 		if ((m = virtqueue_dequeue(vq, NULL)) == NULL)
1347 			break;
1348 		vtnet_discard_rxbuf(sc, m);
1349 	}
1350 }
1351 
1352 static void
1353 vtnet_discard_rxbuf(struct vtnet_softc *sc, struct mbuf *m)
1354 {
1355 	int error;
1356 
1357 	/*
1358 	 * Requeue the discarded mbuf. This should always be
1359 	 * successful since it was just dequeued.
1360 	 */
1361 	error = vtnet_enqueue_rxbuf(sc, m);
1362 	KASSERT(error == 0, ("cannot requeue discarded mbuf"));
1363 }
1364 
1365 static int
1366 vtnet_enqueue_rxbuf(struct vtnet_softc *sc, struct mbuf *m)
1367 {
1368 	struct sglist sg;
1369 	struct sglist_seg segs[VTNET_MAX_RX_SEGS];
1370 	struct vtnet_rx_header *rxhdr;
1371 	struct virtio_net_hdr *hdr;
1372 	uint8_t *mdata;
1373 	int offset, error;
1374 
1375 	ASSERT_SERIALIZED(&sc->vtnet_slz);
1376 	if ((sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG) == 0)
1377 		KASSERT(m->m_next == NULL, ("chained Rx mbuf"));
1378 
1379 	sglist_init(&sg, VTNET_MAX_RX_SEGS, segs);
1380 
1381 	mdata = mtod(m, uint8_t *);
1382 	offset = 0;
1383 
1384 	if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
1385 		rxhdr = (struct vtnet_rx_header *) mdata;
1386 		hdr = &rxhdr->vrh_hdr;
1387 		offset += sizeof(struct vtnet_rx_header);
1388 
1389 		error = sglist_append(&sg, hdr, sc->vtnet_hdr_size);
1390 		KASSERT(error == 0, ("cannot add header to sglist"));
1391 	}
1392 
1393 	error = sglist_append(&sg, mdata + offset, m->m_len - offset);
1394 	if (error)
1395 		return (error);
1396 
1397 	if (m->m_next != NULL) {
1398 		error = sglist_append_mbuf(&sg, m->m_next);
1399 		if (error)
1400 			return (error);
1401 	}
1402 
1403 	return (virtqueue_enqueue(sc->vtnet_rx_vq, m, &sg, 0, sg.sg_nseg));
1404 }
1405 
1406 static void
1407 vtnet_vlan_tag_remove(struct mbuf *m)
1408 {
1409 	struct ether_vlan_header *evl;
1410 
1411 	evl = mtod(m, struct ether_vlan_header *);
1412 
1413 	m->m_pkthdr.ether_vlantag = ntohs(evl->evl_tag);
1414 	m->m_flags |= M_VLANTAG;
1415 
1416 	/* Strip the 802.1Q header. */
1417 	bcopy((char *) evl, (char *) evl + ETHER_VLAN_ENCAP_LEN,
1418 	    ETHER_HDR_LEN - ETHER_TYPE_LEN);
1419 	m_adj(m, ETHER_VLAN_ENCAP_LEN);
1420 }
1421 
1422 /*
1423  * Alternative method of doing receive checksum offloading. Rather
1424  * than parsing the received frame down to the IP header, use the
1425  * csum_offset to determine which CSUM_* flags are appropriate. We
1426  * can get by with doing this only because the checksum offsets are
1427  * unique for the things we care about.
1428  */
1429 static int
1430 vtnet_rx_csum(struct vtnet_softc *sc, struct mbuf *m,
1431     struct virtio_net_hdr *hdr)
1432 {
1433 	struct ether_header *eh;
1434 	struct ether_vlan_header *evh;
1435 	struct udphdr *udp;
1436 	int csum_len;
1437 	uint16_t eth_type;
1438 
1439 	csum_len = hdr->csum_start + hdr->csum_offset;
1440 
1441 	if (csum_len < sizeof(struct ether_header) + sizeof(struct ip))
1442 		return (1);
1443 	if (m->m_len < csum_len)
1444 		return (1);
1445 
1446 	eh = mtod(m, struct ether_header *);
1447 	eth_type = ntohs(eh->ether_type);
1448 	if (eth_type == ETHERTYPE_VLAN) {
1449 		evh = mtod(m, struct ether_vlan_header *);
1450 		eth_type = ntohs(evh->evl_proto);
1451 	}
1452 
1453 	if (eth_type != ETHERTYPE_IP && eth_type != ETHERTYPE_IPV6) {
1454 		sc->vtnet_stats.rx_csum_bad_ethtype++;
1455 		return (1);
1456 	}
1457 
1458 	/* Use the offset to determine the appropriate CSUM_* flags. */
1459 	switch (hdr->csum_offset) {
1460 	case offsetof(struct udphdr, uh_sum):
1461 		if (m->m_len < hdr->csum_start + sizeof(struct udphdr))
1462 			return (1);
1463 		udp = (struct udphdr *)(mtod(m, uint8_t *) + hdr->csum_start);
1464 		if (udp->uh_sum == 0)
1465 			return (0);
1466 
1467 		/* FALLTHROUGH */
1468 
1469 	case offsetof(struct tcphdr, th_sum):
1470 		m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1471 		m->m_pkthdr.csum_data = 0xFFFF;
1472 		break;
1473 
1474 	case offsetof(struct sctphdr, checksum):
1475 		//m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1476 		break;
1477 
1478 	default:
1479 		sc->vtnet_stats.rx_csum_bad_offset++;
1480 		return (1);
1481 	}
1482 
1483 	sc->vtnet_stats.rx_csum_offloaded++;
1484 
1485 	return (0);
1486 }
1487 
1488 static int
1489 vtnet_rxeof_merged(struct vtnet_softc *sc, struct mbuf *m_head, int nbufs)
1490 {
1491 	struct ifnet *ifp;
1492 	struct virtqueue *vq;
1493 	struct mbuf *m, *m_tail;
1494 	int len;
1495 
1496 	ifp = sc->vtnet_ifp;
1497 	vq = sc->vtnet_rx_vq;
1498 	m_tail = m_head;
1499 
1500 	while (--nbufs > 0) {
1501 		m = virtqueue_dequeue(vq, &len);
1502 		if (m == NULL) {
1503 			ifp->if_ierrors++;
1504 			goto fail;
1505 		}
1506 
1507 		if (vtnet_newbuf(sc) != 0) {
1508 			ifp->if_iqdrops++;
1509 			vtnet_discard_rxbuf(sc, m);
1510 			if (nbufs > 1)
1511 				vtnet_discard_merged_rxbuf(sc, nbufs);
1512 			goto fail;
1513 		}
1514 
1515 		if (m->m_len < len)
1516 			len = m->m_len;
1517 
1518 		m->m_len = len;
1519 		m->m_flags &= ~M_PKTHDR;
1520 
1521 		m_head->m_pkthdr.len += len;
1522 		m_tail->m_next = m;
1523 		m_tail = m;
1524 	}
1525 
1526 	return (0);
1527 
1528 fail:
1529 	sc->vtnet_stats.rx_mergeable_failed++;
1530 	m_freem(m_head);
1531 
1532 	return (1);
1533 }
1534 
1535 static int
1536 vtnet_rxeof(struct vtnet_softc *sc, int count, int *rx_npktsp)
1537 {
1538 	struct virtio_net_hdr lhdr;
1539 	struct ifnet *ifp;
1540 	struct virtqueue *vq;
1541 	struct mbuf *m;
1542 	struct ether_header *eh;
1543 	struct virtio_net_hdr *hdr;
1544 	struct virtio_net_hdr_mrg_rxbuf *mhdr;
1545 	int len, deq, nbufs, adjsz, rx_npkts;
1546 
1547 	ifp = sc->vtnet_ifp;
1548 	vq = sc->vtnet_rx_vq;
1549 	hdr = &lhdr;
1550 	deq = 0;
1551 	rx_npkts = 0;
1552 
1553 	ASSERT_SERIALIZED(&sc->vtnet_slz);
1554 
1555 	while (--count >= 0) {
1556 		m = virtqueue_dequeue(vq, &len);
1557 		if (m == NULL)
1558 			break;
1559 		deq++;
1560 
1561 		if (len < sc->vtnet_hdr_size + ETHER_HDR_LEN) {
1562 			ifp->if_ierrors++;
1563 			vtnet_discard_rxbuf(sc, m);
1564 			continue;
1565 		}
1566 
1567 		if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
1568 			nbufs = 1;
1569 			adjsz = sizeof(struct vtnet_rx_header);
1570 			/*
1571 			 * Account for our pad between the header and
1572 			 * the actual start of the frame.
1573 			 */
1574 			len += VTNET_RX_HEADER_PAD;
1575 		} else {
1576 			mhdr = mtod(m, struct virtio_net_hdr_mrg_rxbuf *);
1577 			nbufs = mhdr->num_buffers;
1578 			adjsz = sizeof(struct virtio_net_hdr_mrg_rxbuf);
1579 		}
1580 
1581 		if (vtnet_replace_rxbuf(sc, m, len) != 0) {
1582 			ifp->if_iqdrops++;
1583 			vtnet_discard_rxbuf(sc, m);
1584 			if (nbufs > 1)
1585 				vtnet_discard_merged_rxbuf(sc, nbufs);
1586 			continue;
1587 		}
1588 
1589 		m->m_pkthdr.len = len;
1590 		m->m_pkthdr.rcvif = ifp;
1591 		m->m_pkthdr.csum_flags = 0;
1592 
1593 		if (nbufs > 1) {
1594 			if (vtnet_rxeof_merged(sc, m, nbufs) != 0)
1595 				continue;
1596 		}
1597 
1598 		ifp->if_ipackets++;
1599 
1600 		/*
1601 		 * Save copy of header before we strip it. For both mergeable
1602 		 * and non-mergeable, the VirtIO header is placed first in the
1603 		 * mbuf's data. We no longer need num_buffers, so always use a
1604 		 * virtio_net_hdr.
1605 		 */
1606 		memcpy(hdr, mtod(m, void *), sizeof(struct virtio_net_hdr));
1607 		m_adj(m, adjsz);
1608 
1609 		if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING) {
1610 			eh = mtod(m, struct ether_header *);
1611 			if (eh->ether_type == htons(ETHERTYPE_VLAN)) {
1612 				vtnet_vlan_tag_remove(m);
1613 
1614 				/*
1615 				 * With the 802.1Q header removed, update the
1616 				 * checksum starting location accordingly.
1617 				 */
1618 				if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)
1619 					hdr->csum_start -=
1620 					    ETHER_VLAN_ENCAP_LEN;
1621 			}
1622 		}
1623 
1624 		if (ifp->if_capenable & IFCAP_RXCSUM &&
1625 		    hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
1626 			if (vtnet_rx_csum(sc, m, hdr) != 0)
1627 				sc->vtnet_stats.rx_csum_failed++;
1628 		}
1629 
1630 		lwkt_serialize_exit(&sc->vtnet_slz);
1631 		rx_npkts++;
1632 		(*ifp->if_input)(ifp, m);
1633 		lwkt_serialize_enter(&sc->vtnet_slz);
1634 
1635 		/*
1636 		 * The interface may have been stopped while we were
1637 		 * passing the packet up the network stack.
1638 		 */
1639 		if ((ifp->if_flags & IFF_RUNNING) == 0)
1640 			break;
1641 	}
1642 
1643 	virtqueue_notify(vq, &sc->vtnet_slz);
1644 
1645 	if (rx_npktsp != NULL)
1646 		*rx_npktsp = rx_npkts;
1647 
1648 	return (count > 0 ? 0 : EAGAIN);
1649 }
1650 
1651 static void
1652 vtnet_rx_intr_task(void *arg)
1653 {
1654 	struct vtnet_softc *sc;
1655 	struct ifnet *ifp;
1656 	int more;
1657 
1658 	sc = arg;
1659 	ifp = sc->vtnet_ifp;
1660 
1661 //	lwkt_serialize_enter(&sc->vtnet_slz);
1662 
1663 	if ((ifp->if_flags & IFF_RUNNING) == 0) {
1664 		vtnet_enable_rx_intr(sc);
1665 //		lwkt_serialize_exit(&sc->vtnet_slz);
1666 		return;
1667 	}
1668 
1669 	more = vtnet_rxeof(sc, sc->vtnet_rx_process_limit, NULL);
1670 	if (!more && vtnet_enable_rx_intr(sc) != 0) {
1671 		vtnet_disable_rx_intr(sc);
1672 		more = 1;
1673 	}
1674 
1675 //	lwkt_serialize_exit(&sc->vtnet_slz);
1676 
1677 	if (more) {
1678 		sc->vtnet_stats.rx_task_rescheduled++;
1679 		/* XXX: Loop?! */
1680 		vtnet_rx_intr_task(sc);
1681 	}
1682 }
1683 
1684 static int
1685 vtnet_rx_vq_intr(void *xsc)
1686 {
1687 	struct vtnet_softc *sc;
1688 
1689 	sc = xsc;
1690 
1691 	vtnet_disable_rx_intr(sc);
1692 	vtnet_rx_intr_task(sc);
1693 
1694 	return (1);
1695 }
1696 
1697 static void
1698 vtnet_txeof(struct vtnet_softc *sc)
1699 {
1700 	struct virtqueue *vq;
1701 	struct ifnet *ifp;
1702 	struct vtnet_tx_header *txhdr;
1703 	int deq;
1704 
1705 	vq = sc->vtnet_tx_vq;
1706 	ifp = sc->vtnet_ifp;
1707 	deq = 0;
1708 
1709 	ASSERT_SERIALIZED(&sc->vtnet_slz);
1710 
1711 	while ((txhdr = virtqueue_dequeue(vq, NULL)) != NULL) {
1712 		deq++;
1713 		ifp->if_opackets++;
1714 		m_freem(txhdr->vth_mbuf);
1715 	}
1716 
1717 	if (deq > 0) {
1718 		ifq_clr_oactive(&ifp->if_snd);
1719 		if (virtqueue_empty(vq))
1720 			sc->vtnet_watchdog_timer = 0;
1721 	}
1722 }
1723 
1724 static struct mbuf *
1725 vtnet_tx_offload(struct vtnet_softc *sc, struct mbuf *m,
1726     struct virtio_net_hdr *hdr)
1727 {
1728 	struct ifnet *ifp;
1729 	struct ether_header *eh;
1730 	struct ether_vlan_header *evh;
1731 	struct ip *ip;
1732 	struct ip6_hdr *ip6;
1733 	struct tcphdr *tcp;
1734 	int ip_offset;
1735 	uint16_t eth_type, csum_start;
1736 	uint8_t ip_proto, gso_type;
1737 
1738 	ifp = sc->vtnet_ifp;
1739 	M_ASSERTPKTHDR(m);
1740 
1741 	ip_offset = sizeof(struct ether_header);
1742 	if (m->m_len < ip_offset) {
1743 		if ((m = m_pullup(m, ip_offset)) == NULL)
1744 			return (NULL);
1745 	}
1746 
1747 	eh = mtod(m, struct ether_header *);
1748 	eth_type = ntohs(eh->ether_type);
1749 	if (eth_type == ETHERTYPE_VLAN) {
1750 		ip_offset = sizeof(struct ether_vlan_header);
1751 		if (m->m_len < ip_offset) {
1752 			if ((m = m_pullup(m, ip_offset)) == NULL)
1753 				return (NULL);
1754 		}
1755 		evh = mtod(m, struct ether_vlan_header *);
1756 		eth_type = ntohs(evh->evl_proto);
1757 	}
1758 
1759 	switch (eth_type) {
1760 	case ETHERTYPE_IP:
1761 		if (m->m_len < ip_offset + sizeof(struct ip)) {
1762 			m = m_pullup(m, ip_offset + sizeof(struct ip));
1763 			if (m == NULL)
1764 				return (NULL);
1765 		}
1766 
1767 		ip = (struct ip *)(mtod(m, uint8_t *) + ip_offset);
1768 		ip_proto = ip->ip_p;
1769 		csum_start = ip_offset + (ip->ip_hl << 2);
1770 		gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1771 		break;
1772 
1773 	case ETHERTYPE_IPV6:
1774 		if (m->m_len < ip_offset + sizeof(struct ip6_hdr)) {
1775 			m = m_pullup(m, ip_offset + sizeof(struct ip6_hdr));
1776 			if (m == NULL)
1777 				return (NULL);
1778 		}
1779 
1780 		ip6 = (struct ip6_hdr *)(mtod(m, uint8_t *) + ip_offset);
1781 		/*
1782 		 * XXX Assume no extension headers are present. Presently,
1783 		 * this will always be true in the case of TSO, and FreeBSD
1784 		 * does not perform checksum offloading of IPv6 yet.
1785 		 */
1786 		ip_proto = ip6->ip6_nxt;
1787 		csum_start = ip_offset + sizeof(struct ip6_hdr);
1788 		gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1789 		break;
1790 
1791 	default:
1792 		return (m);
1793 	}
1794 
1795 	if (m->m_pkthdr.csum_flags & VTNET_CSUM_OFFLOAD) {
1796 		hdr->flags |= VIRTIO_NET_HDR_F_NEEDS_CSUM;
1797 		hdr->csum_start = csum_start;
1798 		hdr->csum_offset = m->m_pkthdr.csum_data;
1799 
1800 		sc->vtnet_stats.tx_csum_offloaded++;
1801 	}
1802 
1803 	if (m->m_pkthdr.csum_flags & CSUM_TSO) {
1804 		if (ip_proto != IPPROTO_TCP)
1805 			return (m);
1806 
1807 		if (m->m_len < csum_start + sizeof(struct tcphdr)) {
1808 			m = m_pullup(m, csum_start + sizeof(struct tcphdr));
1809 			if (m == NULL)
1810 				return (NULL);
1811 		}
1812 
1813 		tcp = (struct tcphdr *)(mtod(m, uint8_t *) + csum_start);
1814 		hdr->gso_type = gso_type;
1815 		hdr->hdr_len = csum_start + (tcp->th_off << 2);
1816 		hdr->gso_size = m->m_pkthdr.tso_segsz;
1817 
1818 		if (tcp->th_flags & TH_CWR) {
1819 			/*
1820 			 * Drop if we did not negotiate VIRTIO_NET_F_HOST_ECN.
1821 			 * ECN support is only configurable globally with the
1822 			 * net.inet.tcp.ecn.enable sysctl knob.
1823 			 */
1824 			if ((sc->vtnet_flags & VTNET_FLAG_TSO_ECN) == 0) {
1825 				if_printf(ifp, "TSO with ECN not supported "
1826 				    "by host\n");
1827 				m_freem(m);
1828 				return (NULL);
1829 			}
1830 
1831 			hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
1832 		}
1833 
1834 		sc->vtnet_stats.tx_tso_offloaded++;
1835 	}
1836 
1837 	return (m);
1838 }
1839 
1840 static int
1841 vtnet_enqueue_txbuf(struct vtnet_softc *sc, struct mbuf **m_head,
1842     struct vtnet_tx_header *txhdr)
1843 {
1844 	struct sglist sg;
1845 	struct sglist_seg segs[VTNET_MAX_TX_SEGS];
1846 	struct virtqueue *vq;
1847 	struct mbuf *m;
1848 	int collapsed, error;
1849 
1850 	vq = sc->vtnet_tx_vq;
1851 	m = *m_head;
1852 	collapsed = 0;
1853 
1854 	sglist_init(&sg, VTNET_MAX_TX_SEGS, segs);
1855 	error = sglist_append(&sg, &txhdr->vth_uhdr, sc->vtnet_hdr_size);
1856 	KASSERT(error == 0 && sg.sg_nseg == 1,
1857 	    ("cannot add header to sglist"));
1858 
1859 again:
1860 	error = sglist_append_mbuf(&sg, m);
1861 	if (error) {
1862 		if (collapsed)
1863 			goto fail;
1864 
1865 		//m = m_collapse(m, MB_DONTWAIT, VTNET_MAX_TX_SEGS - 1);
1866 		m = m_defrag(m, MB_DONTWAIT);
1867 		if (m == NULL)
1868 			goto fail;
1869 
1870 		*m_head = m;
1871 		collapsed = 1;
1872 		goto again;
1873 	}
1874 
1875 	txhdr->vth_mbuf = m;
1876 
1877 	return (virtqueue_enqueue(vq, txhdr, &sg, sg.sg_nseg, 0));
1878 
1879 fail:
1880 	m_freem(*m_head);
1881 	*m_head = NULL;
1882 
1883 	return (ENOBUFS);
1884 }
1885 
1886 static struct mbuf *
1887 vtnet_vlan_tag_insert(struct mbuf *m)
1888 {
1889 	struct mbuf *n;
1890 	struct ether_vlan_header *evl;
1891 
1892 	if (M_WRITABLE(m) == 0) {
1893 		n = m_dup(m, MB_DONTWAIT);
1894 		m_freem(m);
1895 		if ((m = n) == NULL)
1896 			return (NULL);
1897 	}
1898 
1899 	M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, MB_DONTWAIT);
1900 	if (m == NULL)
1901 		return (NULL);
1902 	if (m->m_len < sizeof(struct ether_vlan_header)) {
1903 		m = m_pullup(m, sizeof(struct ether_vlan_header));
1904 		if (m == NULL)
1905 			return (NULL);
1906 	}
1907 
1908 	/* Insert 802.1Q header into the existing Ethernet header. */
1909 	evl = mtod(m, struct ether_vlan_header *);
1910 	bcopy((char *) evl + ETHER_VLAN_ENCAP_LEN,
1911 	      (char *) evl, ETHER_HDR_LEN - ETHER_TYPE_LEN);
1912 	evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
1913 	evl->evl_tag = htons(m->m_pkthdr.ether_vlantag);
1914 	m->m_flags &= ~M_VLANTAG;
1915 
1916 	return (m);
1917 }
1918 
1919 static int
1920 vtnet_encap(struct vtnet_softc *sc, struct mbuf **m_head)
1921 {
1922 	struct vtnet_tx_header *txhdr;
1923 	struct virtio_net_hdr *hdr;
1924 	struct mbuf *m;
1925 	int error;
1926 
1927 	txhdr = &sc->vtnet_txhdrarea[sc->vtnet_txhdridx];
1928 	memset(txhdr, 0, sizeof(struct vtnet_tx_header));
1929 
1930 	/*
1931 	 * Always use the non-mergeable header to simplify things. When
1932 	 * the mergeable feature is negotiated, the num_buffers field
1933 	 * must be set to zero. We use vtnet_hdr_size later to enqueue
1934 	 * the correct header size to the host.
1935 	 */
1936 	hdr = &txhdr->vth_uhdr.hdr;
1937 	m = *m_head;
1938 
1939 	error = ENOBUFS;
1940 
1941 	if (m->m_flags & M_VLANTAG) {
1942 		//m = ether_vlanencap(m, m->m_pkthdr.ether_vtag);
1943 		m = vtnet_vlan_tag_insert(m);
1944 		if ((*m_head = m) == NULL)
1945 			goto fail;
1946 		m->m_flags &= ~M_VLANTAG;
1947 	}
1948 
1949 	if (m->m_pkthdr.csum_flags != 0) {
1950 		m = vtnet_tx_offload(sc, m, hdr);
1951 		if ((*m_head = m) == NULL)
1952 			goto fail;
1953 	}
1954 
1955 	error = vtnet_enqueue_txbuf(sc, m_head, txhdr);
1956 	if (error == 0)
1957 		sc->vtnet_txhdridx =
1958 		    (sc->vtnet_txhdridx + 1) % ((sc->vtnet_tx_size / 2) + 1);
1959 fail:
1960 	return (error);
1961 }
1962 
1963 static void
1964 vtnet_start(struct ifnet *ifp, struct ifaltq_subque *ifsq)
1965 {
1966 	struct vtnet_softc *sc;
1967 
1968 	sc = ifp->if_softc;
1969 
1970 	ASSERT_ALTQ_SQ_DEFAULT(ifp, ifsq);
1971 	lwkt_serialize_enter(&sc->vtnet_slz);
1972 	vtnet_start_locked(ifp, ifsq);
1973 	lwkt_serialize_exit(&sc->vtnet_slz);
1974 }
1975 
1976 static void
1977 vtnet_start_locked(struct ifnet *ifp, struct ifaltq_subque *ifsq)
1978 {
1979 	struct vtnet_softc *sc;
1980 	struct virtqueue *vq;
1981 	struct mbuf *m0;
1982 	int enq;
1983 
1984 	sc = ifp->if_softc;
1985 	vq = sc->vtnet_tx_vq;
1986 	enq = 0;
1987 
1988 	ASSERT_SERIALIZED(&sc->vtnet_slz);
1989 
1990 	if ((ifp->if_flags & (IFF_RUNNING)) !=
1991 	    IFF_RUNNING || ((sc->vtnet_flags & VTNET_FLAG_LINK) == 0))
1992 		return;
1993 
1994 #ifdef VTNET_TX_INTR_MODERATION
1995 	if (virtqueue_nused(vq) >= sc->vtnet_tx_size / 2)
1996 		vtnet_txeof(sc);
1997 #endif
1998 
1999 	while (!ifsq_is_empty(ifsq)) {
2000 		if (virtqueue_full(vq)) {
2001 			ifq_set_oactive(&ifp->if_snd);
2002 			break;
2003 		}
2004 
2005 		m0 = ifq_dequeue(&ifp->if_snd);
2006 		if (m0 == NULL)
2007 			break;
2008 
2009 		if (vtnet_encap(sc, &m0) != 0) {
2010 			if (m0 == NULL)
2011 				break;
2012 			ifq_prepend(&ifp->if_snd, m0);
2013 			ifq_set_oactive(&ifp->if_snd);
2014 			break;
2015 		}
2016 
2017 		enq++;
2018 		ETHER_BPF_MTAP(ifp, m0);
2019 	}
2020 
2021 	if (enq > 0) {
2022 		virtqueue_notify(vq, &sc->vtnet_slz);
2023 		sc->vtnet_watchdog_timer = VTNET_WATCHDOG_TIMEOUT;
2024 	}
2025 }
2026 
2027 static void
2028 vtnet_tick(void *xsc)
2029 {
2030 	struct vtnet_softc *sc;
2031 
2032 	sc = xsc;
2033 
2034 #if 0
2035 	ASSERT_SERIALIZED(&sc->vtnet_slz);
2036 #ifdef VTNET_DEBUG
2037 	virtqueue_dump(sc->vtnet_rx_vq);
2038 	virtqueue_dump(sc->vtnet_tx_vq);
2039 #endif
2040 
2041 	vtnet_watchdog(sc);
2042 	callout_reset(&sc->vtnet_tick_ch, hz, vtnet_tick, sc);
2043 #endif
2044 }
2045 
2046 static void
2047 vtnet_tx_intr_task(void *arg)
2048 {
2049 	struct vtnet_softc *sc;
2050 	struct ifnet *ifp;
2051 	struct ifaltq_subque *ifsq;
2052 
2053 	sc = arg;
2054 	ifp = sc->vtnet_ifp;
2055 	ifsq = ifq_get_subq_default(&ifp->if_snd);
2056 
2057 //	lwkt_serialize_enter(&sc->vtnet_slz);
2058 
2059 	if ((ifp->if_flags & IFF_RUNNING) == 0) {
2060 		vtnet_enable_tx_intr(sc);
2061 //		lwkt_serialize_exit(&sc->vtnet_slz);
2062 		return;
2063 	}
2064 
2065 	vtnet_txeof(sc);
2066 
2067 	if (!ifsq_is_empty(ifsq))
2068 		vtnet_start_locked(ifp, ifsq);
2069 
2070 	if (vtnet_enable_tx_intr(sc) != 0) {
2071 		vtnet_disable_tx_intr(sc);
2072 		sc->vtnet_stats.tx_task_rescheduled++;
2073 //		lwkt_serialize_exit(&sc->vtnet_slz);
2074 		vtnet_tx_intr_task(sc);
2075 		/* XXX: loop?! */
2076 		return;
2077 	}
2078 
2079 //	lwkt_serialize_exit(&sc->vtnet_slz);
2080 }
2081 
2082 static int
2083 vtnet_tx_vq_intr(void *xsc)
2084 {
2085 	struct vtnet_softc *sc;
2086 
2087 	sc = xsc;
2088 
2089 	vtnet_disable_tx_intr(sc);
2090 	vtnet_tx_intr_task(sc);
2091 
2092 	return (1);
2093 }
2094 
2095 static void
2096 vtnet_stop(struct vtnet_softc *sc)
2097 {
2098 	device_t dev;
2099 	struct ifnet *ifp;
2100 
2101 	dev = sc->vtnet_dev;
2102 	ifp = sc->vtnet_ifp;
2103 
2104 	ASSERT_SERIALIZED(&sc->vtnet_slz);
2105 
2106 	sc->vtnet_watchdog_timer = 0;
2107 	callout_stop(&sc->vtnet_tick_ch);
2108 	ifq_clr_oactive(&ifp->if_snd);
2109 	ifp->if_flags &= ~(IFF_RUNNING);
2110 
2111 	vtnet_disable_rx_intr(sc);
2112 	vtnet_disable_tx_intr(sc);
2113 
2114 	/*
2115 	 * Stop the host VirtIO adapter. Note this will reset the host
2116 	 * adapter's state back to the pre-initialized state, so in
2117 	 * order to make the device usable again, we must drive it
2118 	 * through virtio_reinit() and virtio_reinit_complete().
2119 	 */
2120 	virtio_stop(dev);
2121 
2122 	sc->vtnet_flags &= ~VTNET_FLAG_LINK;
2123 
2124 	vtnet_free_rx_mbufs(sc);
2125 	vtnet_free_tx_mbufs(sc);
2126 }
2127 
2128 static int
2129 vtnet_reinit(struct vtnet_softc *sc)
2130 {
2131 	struct ifnet *ifp;
2132 	uint64_t features;
2133 
2134 	ifp = sc->vtnet_ifp;
2135 	features = sc->vtnet_features;
2136 
2137 	/*
2138 	 * Re-negotiate with the host, removing any disabled receive
2139 	 * features. Transmit features are disabled only on our side
2140 	 * via if_capenable and if_hwassist.
2141 	 */
2142 
2143 	if (ifp->if_capabilities & IFCAP_RXCSUM) {
2144 		if ((ifp->if_capenable & IFCAP_RXCSUM) == 0)
2145 			features &= ~VIRTIO_NET_F_GUEST_CSUM;
2146 	}
2147 
2148 	if (ifp->if_capabilities & IFCAP_LRO) {
2149 		if ((ifp->if_capenable & IFCAP_LRO) == 0)
2150 			features &= ~VTNET_LRO_FEATURES;
2151 	}
2152 
2153 	if (ifp->if_capabilities & IFCAP_VLAN_HWFILTER) {
2154 		if ((ifp->if_capenable & IFCAP_VLAN_HWFILTER) == 0)
2155 			features &= ~VIRTIO_NET_F_CTRL_VLAN;
2156 	}
2157 
2158 	return (virtio_reinit(sc->vtnet_dev, features));
2159 }
2160 
2161 static void
2162 vtnet_init_locked(struct vtnet_softc *sc)
2163 {
2164 	device_t dev;
2165 	struct ifnet *ifp;
2166 	int error;
2167 
2168 	dev = sc->vtnet_dev;
2169 	ifp = sc->vtnet_ifp;
2170 
2171 	ASSERT_SERIALIZED(&sc->vtnet_slz);
2172 
2173 	if (ifp->if_flags & IFF_RUNNING)
2174 		return;
2175 
2176 	/* Stop host's adapter, cancel any pending I/O. */
2177 	vtnet_stop(sc);
2178 
2179 	/* Reinitialize the host device. */
2180 	error = vtnet_reinit(sc);
2181 	if (error) {
2182 		device_printf(dev,
2183 		    "reinitialization failed, stopping device...\n");
2184 		vtnet_stop(sc);
2185 		return;
2186 	}
2187 
2188 	/* Update host with assigned MAC address. */
2189 	bcopy(IF_LLADDR(ifp), sc->vtnet_hwaddr, ETHER_ADDR_LEN);
2190 	vtnet_set_hwaddr(sc);
2191 
2192 	ifp->if_hwassist = 0;
2193 	if (ifp->if_capenable & IFCAP_TXCSUM)
2194 		ifp->if_hwassist |= VTNET_CSUM_OFFLOAD;
2195 	if (ifp->if_capenable & IFCAP_TSO4)
2196 		ifp->if_hwassist |= CSUM_TSO;
2197 
2198 	error = vtnet_init_rx_vq(sc);
2199 	if (error) {
2200 		device_printf(dev,
2201 		    "cannot allocate mbufs for Rx virtqueue\n");
2202 		vtnet_stop(sc);
2203 		return;
2204 	}
2205 
2206 	if (sc->vtnet_flags & VTNET_FLAG_CTRL_VQ) {
2207 		if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX) {
2208 			/* Restore promiscuous and all-multicast modes. */
2209 			vtnet_rx_filter(sc);
2210 
2211 			/* Restore filtered MAC addresses. */
2212 			vtnet_rx_filter_mac(sc);
2213 		}
2214 
2215 		/* Restore VLAN filters. */
2216 		if (ifp->if_capenable & IFCAP_VLAN_HWFILTER)
2217 			vtnet_rx_filter_vlan(sc);
2218 	}
2219 
2220 	{
2221 		vtnet_enable_rx_intr(sc);
2222 		vtnet_enable_tx_intr(sc);
2223 	}
2224 
2225 	ifp->if_flags |= IFF_RUNNING;
2226 	ifq_clr_oactive(&ifp->if_snd);
2227 
2228 	virtio_reinit_complete(dev);
2229 
2230 	vtnet_update_link_status(sc);
2231 	callout_reset(&sc->vtnet_tick_ch, hz, vtnet_tick, sc);
2232 }
2233 
2234 static void
2235 vtnet_init(void *xsc)
2236 {
2237 	struct vtnet_softc *sc;
2238 
2239 	sc = xsc;
2240 
2241 	lwkt_serialize_enter(&sc->vtnet_slz);
2242 	vtnet_init_locked(sc);
2243 	lwkt_serialize_exit(&sc->vtnet_slz);
2244 }
2245 
2246 static void
2247 vtnet_exec_ctrl_cmd(struct vtnet_softc *sc, void *cookie,
2248     struct sglist *sg, int readable, int writable)
2249 {
2250 	struct virtqueue *vq;
2251 	void *c;
2252 
2253 	vq = sc->vtnet_ctrl_vq;
2254 
2255 	ASSERT_SERIALIZED(&sc->vtnet_slz);
2256 	KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_VQ,
2257 	    ("no control virtqueue"));
2258 	KASSERT(virtqueue_empty(vq),
2259 	    ("control command already enqueued"));
2260 
2261 	if (virtqueue_enqueue(vq, cookie, sg, readable, writable) != 0)
2262 		return;
2263 
2264 	virtqueue_notify(vq, &sc->vtnet_slz);
2265 
2266 	/*
2267 	 * Poll until the command is complete. Previously, we would
2268 	 * sleep until the control virtqueue interrupt handler woke
2269 	 * us up, but dropping the VTNET_MTX leads to serialization
2270 	 * difficulties.
2271 	 *
2272 	 * Furthermore, it appears QEMU/KVM only allocates three MSIX
2273 	 * vectors. Two of those vectors are needed for the Rx and Tx
2274 	 * virtqueues. We do not support sharing both a Vq and config
2275 	 * changed notification on the same MSIX vector.
2276 	 */
2277 	c = virtqueue_poll(vq, NULL);
2278 	KASSERT(c == cookie, ("unexpected control command response"));
2279 }
2280 
2281 static void
2282 vtnet_rx_filter(struct vtnet_softc *sc)
2283 {
2284 	device_t dev;
2285 	struct ifnet *ifp;
2286 
2287 	dev = sc->vtnet_dev;
2288 	ifp = sc->vtnet_ifp;
2289 
2290 	ASSERT_SERIALIZED(&sc->vtnet_slz);
2291 	KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_RX,
2292 	    ("CTRL_RX feature not negotiated"));
2293 
2294 	if (vtnet_set_promisc(sc, ifp->if_flags & IFF_PROMISC) != 0)
2295 		device_printf(dev, "cannot %s promiscuous mode\n",
2296 		    ifp->if_flags & IFF_PROMISC ? "enable" : "disable");
2297 
2298 	if (vtnet_set_allmulti(sc, ifp->if_flags & IFF_ALLMULTI) != 0)
2299 		device_printf(dev, "cannot %s all-multicast mode\n",
2300 		    ifp->if_flags & IFF_ALLMULTI ? "enable" : "disable");
2301 }
2302 
2303 static int
2304 vtnet_ctrl_rx_cmd(struct vtnet_softc *sc, int cmd, int on)
2305 {
2306 	struct virtio_net_ctrl_hdr hdr __aligned(2);
2307 	struct sglist_seg segs[3];
2308 	struct sglist sg;
2309 	uint8_t onoff, ack;
2310 	int error;
2311 
2312 	if ((sc->vtnet_flags & VTNET_FLAG_CTRL_RX) == 0)
2313 		return (ENOTSUP);
2314 
2315 	error = 0;
2316 
2317 	hdr.class = VIRTIO_NET_CTRL_RX;
2318 	hdr.cmd = cmd;
2319 	onoff = !!on;
2320 	ack = VIRTIO_NET_ERR;
2321 
2322 	sglist_init(&sg, 3, segs);
2323 	error |= sglist_append(&sg, &hdr, sizeof(struct virtio_net_ctrl_hdr));
2324 	error |= sglist_append(&sg, &onoff, sizeof(uint8_t));
2325 	error |= sglist_append(&sg, &ack, sizeof(uint8_t));
2326 	KASSERT(error == 0 && sg.sg_nseg == 3,
2327 	    ("error adding Rx filter message to sglist"));
2328 
2329 	vtnet_exec_ctrl_cmd(sc, &ack, &sg, sg.sg_nseg - 1, 1);
2330 
2331 	return (ack == VIRTIO_NET_OK ? 0 : EIO);
2332 }
2333 
2334 static int
2335 vtnet_set_promisc(struct vtnet_softc *sc, int on)
2336 {
2337 
2338 	return (vtnet_ctrl_rx_cmd(sc, VIRTIO_NET_CTRL_RX_PROMISC, on));
2339 }
2340 
2341 static int
2342 vtnet_set_allmulti(struct vtnet_softc *sc, int on)
2343 {
2344 
2345 	return (vtnet_ctrl_rx_cmd(sc, VIRTIO_NET_CTRL_RX_ALLMULTI, on));
2346 }
2347 
2348 static void
2349 vtnet_rx_filter_mac(struct vtnet_softc *sc)
2350 {
2351 	struct virtio_net_ctrl_hdr hdr __aligned(2);
2352 	struct vtnet_mac_filter *filter;
2353 	struct sglist_seg segs[4];
2354 	struct sglist sg;
2355 	struct ifnet *ifp;
2356 	struct ifaddr *ifa;
2357         struct ifaddr_container *ifac;
2358 	struct ifmultiaddr *ifma;
2359 	int ucnt, mcnt, promisc, allmulti, error;
2360 	uint8_t ack;
2361 
2362 	ifp = sc->vtnet_ifp;
2363 	ucnt = 0;
2364 	mcnt = 0;
2365 	promisc = 0;
2366 	allmulti = 0;
2367 	error = 0;
2368 
2369 	ASSERT_SERIALIZED(&sc->vtnet_slz);
2370 	KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_RX,
2371 	    ("CTRL_RX feature not negotiated"));
2372 
2373 	/* Use the MAC filtering table allocated in vtnet_attach. */
2374 	filter = sc->vtnet_macfilter;
2375 	memset(filter, 0, sizeof(struct vtnet_mac_filter));
2376 
2377 	/* Unicast MAC addresses: */
2378 	//if_addr_rlock(ifp);
2379 	TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
2380 		ifa = ifac->ifa;
2381 		if (ifa->ifa_addr->sa_family != AF_LINK)
2382 			continue;
2383 		else if (ucnt == VTNET_MAX_MAC_ENTRIES)
2384 			break;
2385 
2386 		bcopy(LLADDR((struct sockaddr_dl *)ifa->ifa_addr),
2387 		    &filter->vmf_unicast.macs[ucnt], ETHER_ADDR_LEN);
2388 		ucnt++;
2389 	}
2390 	//if_addr_runlock(ifp);
2391 
2392 	if (ucnt >= VTNET_MAX_MAC_ENTRIES) {
2393 		promisc = 1;
2394 		filter->vmf_unicast.nentries = 0;
2395 
2396 		if_printf(ifp, "more than %d MAC addresses assigned, "
2397 		    "falling back to promiscuous mode\n",
2398 		    VTNET_MAX_MAC_ENTRIES);
2399 	} else
2400 		filter->vmf_unicast.nentries = ucnt;
2401 
2402 	/* Multicast MAC addresses: */
2403 	//if_maddr_rlock(ifp);
2404 	TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
2405 		if (ifma->ifma_addr->sa_family != AF_LINK)
2406 			continue;
2407 		else if (mcnt == VTNET_MAX_MAC_ENTRIES)
2408 			break;
2409 
2410 		bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
2411 		    &filter->vmf_multicast.macs[mcnt], ETHER_ADDR_LEN);
2412 		mcnt++;
2413 	}
2414 	//if_maddr_runlock(ifp);
2415 
2416 	if (mcnt >= VTNET_MAX_MAC_ENTRIES) {
2417 		allmulti = 1;
2418 		filter->vmf_multicast.nentries = 0;
2419 
2420 		if_printf(ifp, "more than %d multicast MAC addresses "
2421 		    "assigned, falling back to all-multicast mode\n",
2422 		    VTNET_MAX_MAC_ENTRIES);
2423 	} else
2424 		filter->vmf_multicast.nentries = mcnt;
2425 
2426 	if (promisc && allmulti)
2427 		goto out;
2428 
2429 	hdr.class = VIRTIO_NET_CTRL_MAC;
2430 	hdr.cmd = VIRTIO_NET_CTRL_MAC_TABLE_SET;
2431 	ack = VIRTIO_NET_ERR;
2432 
2433 	sglist_init(&sg, 4, segs);
2434 	error |= sglist_append(&sg, &hdr, sizeof(struct virtio_net_ctrl_hdr));
2435 	error |= sglist_append(&sg, &filter->vmf_unicast,
2436 	    sizeof(struct vtnet_mac_table));
2437 	error |= sglist_append(&sg, &filter->vmf_multicast,
2438 	    sizeof(struct vtnet_mac_table));
2439 	error |= sglist_append(&sg, &ack, sizeof(uint8_t));
2440 	KASSERT(error == 0 && sg.sg_nseg == 4,
2441 	    ("error adding MAC filtering message to sglist"));
2442 
2443 	vtnet_exec_ctrl_cmd(sc, &ack, &sg, sg.sg_nseg - 1, 1);
2444 
2445 	if (ack != VIRTIO_NET_OK)
2446 		if_printf(ifp, "error setting host MAC filter table\n");
2447 
2448 out:
2449 	if (promisc)
2450 		if (vtnet_set_promisc(sc, 1) != 0)
2451 			if_printf(ifp, "cannot enable promiscuous mode\n");
2452 	if (allmulti)
2453 		if (vtnet_set_allmulti(sc, 1) != 0)
2454 			if_printf(ifp, "cannot enable all-multicast mode\n");
2455 }
2456 
2457 static int
2458 vtnet_exec_vlan_filter(struct vtnet_softc *sc, int add, uint16_t tag)
2459 {
2460 	struct virtio_net_ctrl_hdr hdr __aligned(2);
2461 	struct sglist_seg segs[3];
2462 	struct sglist sg;
2463 	uint8_t ack;
2464 	int error;
2465 
2466 	hdr.class = VIRTIO_NET_CTRL_VLAN;
2467 	hdr.cmd = add ? VIRTIO_NET_CTRL_VLAN_ADD : VIRTIO_NET_CTRL_VLAN_DEL;
2468 	ack = VIRTIO_NET_ERR;
2469 	error = 0;
2470 
2471 	sglist_init(&sg, 3, segs);
2472 	error |= sglist_append(&sg, &hdr, sizeof(struct virtio_net_ctrl_hdr));
2473 	error |= sglist_append(&sg, &tag, sizeof(uint16_t));
2474 	error |= sglist_append(&sg, &ack, sizeof(uint8_t));
2475 	KASSERT(error == 0 && sg.sg_nseg == 3,
2476 	    ("error adding VLAN control message to sglist"));
2477 
2478 	vtnet_exec_ctrl_cmd(sc, &ack, &sg, sg.sg_nseg - 1, 1);
2479 
2480 	return (ack == VIRTIO_NET_OK ? 0 : EIO);
2481 }
2482 
2483 static void
2484 vtnet_rx_filter_vlan(struct vtnet_softc *sc)
2485 {
2486 	device_t dev;
2487 	uint32_t w, mask;
2488 	uint16_t tag;
2489 	int i, nvlans, error;
2490 
2491 	ASSERT_SERIALIZED(&sc->vtnet_slz);
2492 	KASSERT(sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER,
2493 	    ("VLAN_FILTER feature not negotiated"));
2494 
2495 	dev = sc->vtnet_dev;
2496 	nvlans = sc->vtnet_nvlans;
2497 	error = 0;
2498 
2499 	/* Enable filtering for each configured VLAN. */
2500 	for (i = 0; i < VTNET_VLAN_SHADOW_SIZE && nvlans > 0; i++) {
2501 		w = sc->vtnet_vlan_shadow[i];
2502 		for (mask = 1, tag = i * 32; w != 0; mask <<= 1, tag++) {
2503 			if ((w & mask) != 0) {
2504 				w &= ~mask;
2505 				nvlans--;
2506 				if (vtnet_exec_vlan_filter(sc, 1, tag) != 0)
2507 					error++;
2508 			}
2509 		}
2510 	}
2511 
2512 	KASSERT(nvlans == 0, ("VLAN count incorrect"));
2513 	if (error)
2514 		device_printf(dev, "cannot restore VLAN filter table\n");
2515 }
2516 
2517 static void
2518 vtnet_set_vlan_filter(struct vtnet_softc *sc, int add, uint16_t tag)
2519 {
2520 	struct ifnet *ifp;
2521 	int idx, bit;
2522 
2523 	KASSERT(sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER,
2524 	    ("VLAN_FILTER feature not negotiated"));
2525 
2526 	if ((tag == 0) || (tag > 4095))
2527 		return;
2528 
2529 	ifp = sc->vtnet_ifp;
2530 	idx = (tag >> 5) & 0x7F;
2531 	bit = tag & 0x1F;
2532 
2533 	lwkt_serialize_enter(&sc->vtnet_slz);
2534 
2535 	/* Update shadow VLAN table. */
2536 	if (add) {
2537 		sc->vtnet_nvlans++;
2538 		sc->vtnet_vlan_shadow[idx] |= (1 << bit);
2539 	} else {
2540 		sc->vtnet_nvlans--;
2541 		sc->vtnet_vlan_shadow[idx] &= ~(1 << bit);
2542 	}
2543 
2544 	if (ifp->if_capenable & IFCAP_VLAN_HWFILTER) {
2545 		if (vtnet_exec_vlan_filter(sc, add, tag) != 0) {
2546 			device_printf(sc->vtnet_dev,
2547 			    "cannot %s VLAN %d %s the host filter table\n",
2548 			    add ? "add" : "remove", tag,
2549 			    add ? "to" : "from");
2550 		}
2551 	}
2552 
2553 	lwkt_serialize_exit(&sc->vtnet_slz);
2554 }
2555 
2556 static void
2557 vtnet_register_vlan(void *arg, struct ifnet *ifp, uint16_t tag)
2558 {
2559 
2560 	if (ifp->if_softc != arg)
2561 		return;
2562 
2563 	vtnet_set_vlan_filter(arg, 1, tag);
2564 }
2565 
2566 static void
2567 vtnet_unregister_vlan(void *arg, struct ifnet *ifp, uint16_t tag)
2568 {
2569 
2570 	if (ifp->if_softc != arg)
2571 		return;
2572 
2573 	vtnet_set_vlan_filter(arg, 0, tag);
2574 }
2575 
2576 static int
2577 vtnet_ifmedia_upd(struct ifnet *ifp)
2578 {
2579 	struct vtnet_softc *sc;
2580 	struct ifmedia *ifm;
2581 
2582 	sc = ifp->if_softc;
2583 	ifm = &sc->vtnet_media;
2584 
2585 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
2586 		return (EINVAL);
2587 
2588 	return (0);
2589 }
2590 
2591 static void
2592 vtnet_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
2593 {
2594 	struct vtnet_softc *sc;
2595 
2596 	sc = ifp->if_softc;
2597 
2598 	ifmr->ifm_status = IFM_AVALID;
2599 	ifmr->ifm_active = IFM_ETHER;
2600 
2601 	lwkt_serialize_enter(&sc->vtnet_slz);
2602 	if (vtnet_is_link_up(sc) != 0) {
2603 		ifmr->ifm_status |= IFM_ACTIVE;
2604 		ifmr->ifm_active |= VTNET_MEDIATYPE;
2605 	} else
2606 		ifmr->ifm_active |= IFM_NONE;
2607 	lwkt_serialize_exit(&sc->vtnet_slz);
2608 }
2609 
2610 static void
2611 vtnet_add_statistics(struct vtnet_softc *sc)
2612 {
2613 	device_t dev;
2614 	struct vtnet_statistics *stats;
2615         //struct sysctl_ctx_list *ctx;
2616 	//struct sysctl_oid *tree;
2617 	//struct sysctl_oid_list *child;
2618 	int error = 0;
2619 
2620 	dev = sc->vtnet_dev;
2621 	stats = &sc->vtnet_stats;
2622 	sysctl_ctx_init(&sc->vtnet_sysctl_ctx);
2623 	sc->vtnet_sysctl_tree = SYSCTL_ADD_NODE(&sc->vtnet_sysctl_ctx,
2624 						SYSCTL_STATIC_CHILDREN(_hw),
2625 						OID_AUTO,
2626 						device_get_nameunit(dev),
2627 						CTLFLAG_RD, 0, "");
2628 
2629 	if (sc->vtnet_sysctl_tree == NULL) {
2630 		device_printf(dev, "can't add sysctl node\n");
2631 		error = ENXIO;
2632 	}
2633 
2634 
2635 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx,
2636 			 SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO,
2637 			 "mbuf_alloc_failed", CTLFLAG_RD, &stats->mbuf_alloc_failed,
2638 			 "Mbuf cluster allocation failures");
2639 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx,
2640 			 SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO,
2641 			 "rx_frame_too_large", CTLFLAG_RD, &stats->rx_frame_too_large,
2642 			 "Received frame larger than the mbuf chain");
2643 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx,SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_enq_replacement_failed",
2644 	    CTLFLAG_RD, &stats->rx_enq_replacement_failed,
2645 	    "Enqueuing the replacement receive mbuf failed");
2646 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_mergeable_failed",
2647 	    CTLFLAG_RD, &stats->rx_mergeable_failed,
2648 	    "Mergeable buffers receive failures");
2649 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_csum_bad_ethtype",
2650 	    CTLFLAG_RD, &stats->rx_csum_bad_ethtype,
2651 	    "Received checksum offloaded buffer with unsupported "
2652 	    "Ethernet type");
2653 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_csum_bad_start",
2654 	    CTLFLAG_RD, &stats->rx_csum_bad_start,
2655 	    "Received checksum offloaded buffer with incorrect start offset");
2656 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_csum_bad_ipproto",
2657 	    CTLFLAG_RD, &stats->rx_csum_bad_ipproto,
2658 	    "Received checksum offloaded buffer with incorrect IP protocol");
2659 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_csum_bad_offset",
2660 	    CTLFLAG_RD, &stats->rx_csum_bad_offset,
2661 	    "Received checksum offloaded buffer with incorrect offset");
2662 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_csum_failed",
2663 	    CTLFLAG_RD, &stats->rx_csum_failed,
2664 	    "Received buffer checksum offload failed");
2665 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_csum_offloaded",
2666 	    CTLFLAG_RD, &stats->rx_csum_offloaded,
2667 	    "Received buffer checksum offload succeeded");
2668 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "rx_task_rescheduled",
2669 	    CTLFLAG_RD, &stats->rx_task_rescheduled,
2670 	    "Times the receive interrupt task rescheduled itself");
2671 
2672 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "tx_csum_offloaded",
2673 	    CTLFLAG_RD, &stats->tx_csum_offloaded,
2674 	    "Offloaded checksum of transmitted buffer");
2675 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "tx_tso_offloaded",
2676 	    CTLFLAG_RD, &stats->tx_tso_offloaded,
2677 	    "Segmentation offload of transmitted buffer");
2678 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "tx_csum_bad_ethtype",
2679 	    CTLFLAG_RD, &stats->tx_csum_bad_ethtype,
2680 	    "Aborted transmit of checksum offloaded buffer with unknown "
2681 	    "Ethernet type");
2682 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "tx_tso_bad_ethtype",
2683 	    CTLFLAG_RD, &stats->tx_tso_bad_ethtype,
2684 	    "Aborted transmit of TSO buffer with unknown Ethernet type");
2685 	SYSCTL_ADD_ULONG(&sc->vtnet_sysctl_ctx, SYSCTL_CHILDREN(sc->vtnet_sysctl_tree), OID_AUTO, "tx_task_rescheduled",
2686 	    CTLFLAG_RD, &stats->tx_task_rescheduled,
2687 	    "Times the transmit interrupt task rescheduled itself");
2688 }
2689 
2690 static int
2691 vtnet_enable_rx_intr(struct vtnet_softc *sc)
2692 {
2693 
2694 	return (virtqueue_enable_intr(sc->vtnet_rx_vq));
2695 }
2696 
2697 static void
2698 vtnet_disable_rx_intr(struct vtnet_softc *sc)
2699 {
2700 
2701 	virtqueue_disable_intr(sc->vtnet_rx_vq);
2702 }
2703 
2704 static int
2705 vtnet_enable_tx_intr(struct vtnet_softc *sc)
2706 {
2707 
2708 #ifdef VTNET_TX_INTR_MODERATION
2709 	return (0);
2710 #else
2711 	return (virtqueue_enable_intr(sc->vtnet_tx_vq));
2712 #endif
2713 }
2714 
2715 static void
2716 vtnet_disable_tx_intr(struct vtnet_softc *sc)
2717 {
2718 
2719 	virtqueue_disable_intr(sc->vtnet_tx_vq);
2720 }
2721