xref: /freebsd/sys/dev/gve/gve_main.c (revision 5b31cc94b10d4bb7109c6b27940a0fc76a44a331)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2023 Google LLC
5  *
6  * Redistribution and use in source and binary forms, with or without modification,
7  * are permitted provided that the following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright notice, this
10  *    list of conditions and the following disclaimer.
11  *
12  * 2. Redistributions in binary form must reproduce the above copyright notice,
13  *    this list of conditions and the following disclaimer in the documentation
14  *    and/or other materials provided with the distribution.
15  *
16  * 3. Neither the name of the copyright holder nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software without
18  *    specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
22  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
23  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
24  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
25  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
27  * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
29  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include "gve.h"
32 #include "gve_adminq.h"
33 
34 #define GVE_DRIVER_VERSION "GVE-FBSD-1.0.1\n"
35 #define GVE_VERSION_MAJOR 1
36 #define GVE_VERSION_MINOR 0
37 #define GVE_VERSION_SUB 1
38 
39 #define GVE_DEFAULT_RX_COPYBREAK 256
40 
41 /* Devices supported by this driver. */
42 static struct gve_dev {
43         uint16_t vendor_id;
44         uint16_t device_id;
45         const char *name;
46 } gve_devs[] = {
47 	{ PCI_VENDOR_ID_GOOGLE, PCI_DEV_ID_GVNIC, "gVNIC" }
48 };
49 
50 struct sx gve_global_lock;
51 
52 static int
53 gve_verify_driver_compatibility(struct gve_priv *priv)
54 {
55 	int err;
56 	struct gve_driver_info *driver_info;
57 	struct gve_dma_handle driver_info_mem;
58 
59 	err = gve_dma_alloc_coherent(priv, sizeof(struct gve_driver_info),
60 	    PAGE_SIZE, &driver_info_mem);
61 
62 	if (err != 0)
63 		return (ENOMEM);
64 
65 	driver_info = driver_info_mem.cpu_addr;
66 
67 	*driver_info = (struct gve_driver_info) {
68 		.os_type = 3, /* Freebsd */
69 		.driver_major = GVE_VERSION_MAJOR,
70 		.driver_minor = GVE_VERSION_MINOR,
71 		.driver_sub = GVE_VERSION_SUB,
72 		.os_version_major = htobe32(FBSD_VERSION_MAJOR),
73 		.os_version_minor = htobe32(FBSD_VERSION_MINOR),
74 		.os_version_sub = htobe32(FBSD_VERSION_PATCH),
75 		.driver_capability_flags = {
76 			htobe64(GVE_DRIVER_CAPABILITY_FLAGS1),
77 			htobe64(GVE_DRIVER_CAPABILITY_FLAGS2),
78 			htobe64(GVE_DRIVER_CAPABILITY_FLAGS3),
79 			htobe64(GVE_DRIVER_CAPABILITY_FLAGS4),
80 		},
81 	};
82 
83 	snprintf(driver_info->os_version_str1, sizeof(driver_info->os_version_str1),
84 	    "FreeBSD %u", __FreeBSD_version);
85 
86 	bus_dmamap_sync(driver_info_mem.tag, driver_info_mem.map,
87 	    BUS_DMASYNC_PREREAD);
88 
89 	err = gve_adminq_verify_driver_compatibility(priv,
90 	    sizeof(struct gve_driver_info), driver_info_mem.bus_addr);
91 
92 	/* It's ok if the device doesn't support this */
93 	if (err == EOPNOTSUPP)
94 		err = 0;
95 
96 	gve_dma_free_coherent(&driver_info_mem);
97 
98 	return (err);
99 }
100 
101 static int
102 gve_up(struct gve_priv *priv)
103 {
104 	if_t ifp = priv->ifp;
105 	int err;
106 
107 	GVE_IFACE_LOCK_ASSERT(priv->gve_iface_lock);
108 
109 	if (device_is_attached(priv->dev) == 0) {
110 		device_printf(priv->dev, "Cannot bring the iface up when detached\n");
111 		return (ENXIO);
112 	}
113 
114 	if (gve_get_state_flag(priv, GVE_STATE_FLAG_QUEUES_UP))
115 		return (0);
116 
117 	if_clearhwassist(ifp);
118 	if (if_getcapenable(ifp) & IFCAP_TXCSUM)
119 		if_sethwassistbits(ifp, CSUM_TCP | CSUM_UDP, 0);
120 	if (if_getcapenable(ifp) & IFCAP_TXCSUM_IPV6)
121 		if_sethwassistbits(ifp, CSUM_IP6_TCP | CSUM_IP6_UDP, 0);
122 	if (if_getcapenable(ifp) & IFCAP_TSO4)
123 		if_sethwassistbits(ifp, CSUM_IP_TSO, 0);
124 	if (if_getcapenable(ifp) & IFCAP_TSO6)
125 		if_sethwassistbits(ifp, CSUM_IP6_TSO, 0);
126 
127 	err = gve_register_qpls(priv);
128 	if (err != 0)
129 		goto reset;
130 
131 	err = gve_create_rx_rings(priv);
132 	if (err != 0)
133 		goto reset;
134 
135 	err = gve_create_tx_rings(priv);
136 	if (err != 0)
137 		goto reset;
138 
139 	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, IFF_DRV_OACTIVE);
140 
141 	if (!gve_get_state_flag(priv, GVE_STATE_FLAG_LINK_UP)) {
142 		if_link_state_change(ifp, LINK_STATE_UP);
143 		gve_set_state_flag(priv, GVE_STATE_FLAG_LINK_UP);
144 	}
145 
146 	gve_unmask_all_queue_irqs(priv);
147 	gve_set_state_flag(priv, GVE_STATE_FLAG_QUEUES_UP);
148 	priv->interface_up_cnt++;
149 	return (0);
150 
151 reset:
152 	gve_schedule_reset(priv);
153 	return (err);
154 }
155 
156 static void
157 gve_down(struct gve_priv *priv)
158 {
159 	GVE_IFACE_LOCK_ASSERT(priv->gve_iface_lock);
160 
161 	if (!gve_get_state_flag(priv, GVE_STATE_FLAG_QUEUES_UP))
162 		return;
163 
164 	if (gve_get_state_flag(priv, GVE_STATE_FLAG_LINK_UP)) {
165 		if_link_state_change(priv->ifp, LINK_STATE_DOWN);
166 		gve_clear_state_flag(priv, GVE_STATE_FLAG_LINK_UP);
167 	}
168 
169 	if_setdrvflagbits(priv->ifp, IFF_DRV_OACTIVE, IFF_DRV_RUNNING);
170 
171 	if (gve_destroy_rx_rings(priv) != 0)
172 		goto reset;
173 
174 	if (gve_destroy_tx_rings(priv) != 0)
175 		goto reset;
176 
177 	if (gve_unregister_qpls(priv) != 0)
178 		goto reset;
179 
180 	gve_mask_all_queue_irqs(priv);
181 	gve_clear_state_flag(priv, GVE_STATE_FLAG_QUEUES_UP);
182 	priv->interface_down_cnt++;
183 	return;
184 
185 reset:
186 	gve_schedule_reset(priv);
187 }
188 
189 static int
190 gve_set_mtu(if_t ifp, uint32_t new_mtu)
191 {
192 	struct gve_priv *priv = if_getsoftc(ifp);
193 	int err;
194 
195 	if ((new_mtu > priv->max_mtu) || (new_mtu < ETHERMIN)) {
196 		device_printf(priv->dev, "Invalid new MTU setting. new mtu: %d max mtu: %d min mtu: %d\n",
197 		    new_mtu, priv->max_mtu, ETHERMIN);
198 		return (EINVAL);
199 	}
200 
201 	err = gve_adminq_set_mtu(priv, new_mtu);
202 	if (err == 0) {
203 		if (bootverbose)
204 			device_printf(priv->dev, "MTU set to %d\n", new_mtu);
205 		if_setmtu(ifp, new_mtu);
206 	} else {
207 		device_printf(priv->dev, "Failed to set MTU to %d\n", new_mtu);
208 	}
209 
210 	return (err);
211 }
212 
213 static void
214 gve_init(void *arg)
215 {
216 	struct gve_priv *priv = (struct gve_priv *)arg;
217 
218 	if (!gve_get_state_flag(priv, GVE_STATE_FLAG_QUEUES_UP)) {
219 		GVE_IFACE_LOCK_LOCK(priv->gve_iface_lock);
220 		gve_up(priv);
221 		GVE_IFACE_LOCK_UNLOCK(priv->gve_iface_lock);
222 	}
223 }
224 
225 static int
226 gve_ioctl(if_t ifp, u_long command, caddr_t data)
227 {
228 	struct gve_priv *priv;
229 	struct ifreq *ifr;
230 	int rc = 0;
231 
232 	priv = if_getsoftc(ifp);
233 	ifr = (struct ifreq *)data;
234 
235 	switch (command) {
236 	case SIOCSIFMTU:
237 		if (if_getmtu(ifp) == ifr->ifr_mtu)
238 			break;
239 		GVE_IFACE_LOCK_LOCK(priv->gve_iface_lock);
240 		gve_down(priv);
241 		gve_set_mtu(ifp, ifr->ifr_mtu);
242 		rc = gve_up(priv);
243 		GVE_IFACE_LOCK_UNLOCK(priv->gve_iface_lock);
244 		break;
245 
246 	case SIOCSIFFLAGS:
247 		if ((if_getflags(ifp) & IFF_UP) != 0) {
248 			if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) == 0) {
249 				GVE_IFACE_LOCK_LOCK(priv->gve_iface_lock);
250 				rc = gve_up(priv);
251 				GVE_IFACE_LOCK_UNLOCK(priv->gve_iface_lock);
252 			}
253 		} else {
254 			if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0) {
255 				GVE_IFACE_LOCK_LOCK(priv->gve_iface_lock);
256 				gve_down(priv);
257 				GVE_IFACE_LOCK_UNLOCK(priv->gve_iface_lock);
258 			}
259 		}
260 		break;
261 
262 	case SIOCSIFCAP:
263 		if (ifr->ifr_reqcap == if_getcapenable(ifp))
264 			break;
265 		GVE_IFACE_LOCK_LOCK(priv->gve_iface_lock);
266 		gve_down(priv);
267 		if_setcapenable(ifp, ifr->ifr_reqcap);
268 		rc = gve_up(priv);
269 		GVE_IFACE_LOCK_UNLOCK(priv->gve_iface_lock);
270 		break;
271 
272 	case SIOCSIFMEDIA:
273 		/* FALLTHROUGH */
274 	case SIOCGIFMEDIA:
275 		rc = ifmedia_ioctl(ifp, ifr, &priv->media, command);
276 		break;
277 
278 	default:
279 		rc = ether_ioctl(ifp, command, data);
280 		break;
281 	}
282 
283 	return (rc);
284 }
285 
286 static int
287 gve_media_change(if_t ifp)
288 {
289 	struct gve_priv *priv = if_getsoftc(ifp);
290 
291 	device_printf(priv->dev, "Media change not supported\n");
292 	return (0);
293 }
294 
295 static void
296 gve_media_status(if_t ifp, struct ifmediareq *ifmr)
297 {
298 	struct gve_priv *priv = if_getsoftc(ifp);
299 
300 	GVE_IFACE_LOCK_LOCK(priv->gve_iface_lock);
301 
302 	ifmr->ifm_status = IFM_AVALID;
303 	ifmr->ifm_active = IFM_ETHER;
304 
305 	if (gve_get_state_flag(priv, GVE_STATE_FLAG_LINK_UP)) {
306 		ifmr->ifm_status |= IFM_ACTIVE;
307 		ifmr->ifm_active |= IFM_AUTO;
308 	} else {
309 		ifmr->ifm_active |= IFM_NONE;
310 	}
311 
312 	GVE_IFACE_LOCK_UNLOCK(priv->gve_iface_lock);
313 }
314 
315 static uint64_t
316 gve_get_counter(if_t ifp, ift_counter cnt)
317 {
318 	struct gve_priv *priv;
319 	uint64_t rpackets = 0;
320 	uint64_t tpackets = 0;
321 	uint64_t rbytes = 0;
322 	uint64_t tbytes = 0;
323 	uint64_t rx_dropped_pkt = 0;
324 	uint64_t tx_dropped_pkt = 0;
325 
326 	priv = if_getsoftc(ifp);
327 
328 	gve_accum_stats(priv, &rpackets, &rbytes, &rx_dropped_pkt, &tpackets,
329 	    &tbytes, &tx_dropped_pkt);
330 
331 	switch (cnt) {
332 	case IFCOUNTER_IPACKETS:
333 		return (rpackets);
334 
335 	case IFCOUNTER_OPACKETS:
336 		return (tpackets);
337 
338 	case IFCOUNTER_IBYTES:
339 		return (rbytes);
340 
341 	case IFCOUNTER_OBYTES:
342 		return (tbytes);
343 
344 	case IFCOUNTER_IQDROPS:
345 		return (rx_dropped_pkt);
346 
347 	case IFCOUNTER_OQDROPS:
348 		return (tx_dropped_pkt);
349 
350 	default:
351 		return (if_get_counter_default(ifp, cnt));
352 	}
353 }
354 
355 static int
356 gve_setup_ifnet(device_t dev, struct gve_priv *priv)
357 {
358 	int caps = 0;
359 	if_t ifp;
360 
361 	ifp = priv->ifp = if_alloc(IFT_ETHER);
362 	if (ifp == NULL) {
363 		device_printf(priv->dev, "Failed to allocate ifnet struct\n");
364 		return (ENXIO);
365 	}
366 
367 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
368 	if_setsoftc(ifp, priv);
369 	if_setdev(ifp, dev);
370 	if_setinitfn(ifp, gve_init);
371 	if_setioctlfn(ifp, gve_ioctl);
372 	if_settransmitfn(ifp, gve_xmit_ifp);
373 	if_setqflushfn(ifp, gve_qflush);
374 
375 #if __FreeBSD_version >= 1400086
376 	if_setflags(ifp, IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
377 #else
378 	if_setflags(ifp, IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST | IFF_KNOWSEPOCH);
379 #endif
380 
381 	ifmedia_init(&priv->media, IFM_IMASK, gve_media_change, gve_media_status);
382 	if_setgetcounterfn(ifp, gve_get_counter);
383 
384 	caps = IFCAP_RXCSUM |
385 	       IFCAP_TXCSUM |
386 	       IFCAP_TXCSUM_IPV6 |
387 	       IFCAP_TSO |
388 	       IFCAP_LRO;
389 
390 	if ((priv->supported_features & GVE_SUP_JUMBO_FRAMES_MASK) != 0)
391 		caps |= IFCAP_JUMBO_MTU;
392 
393 	if_setcapabilities(ifp, caps);
394 	if_setcapenable(ifp, caps);
395 
396 	if (bootverbose)
397 		device_printf(priv->dev, "Setting initial MTU to %d\n", priv->max_mtu);
398 	if_setmtu(ifp, priv->max_mtu);
399 
400 	ether_ifattach(ifp, priv->mac);
401 
402 	ifmedia_add(&priv->media, IFM_ETHER | IFM_AUTO, 0, NULL);
403 	ifmedia_set(&priv->media, IFM_ETHER | IFM_AUTO);
404 
405 	return (0);
406 }
407 
408 static int
409 gve_alloc_counter_array(struct gve_priv *priv)
410 {
411 	int err;
412 
413 	err = gve_dma_alloc_coherent(priv, sizeof(uint32_t) * priv->num_event_counters,
414 	    PAGE_SIZE, &priv->counter_array_mem);
415 	if (err != 0)
416 		return (err);
417 
418 	priv->counters = priv->counter_array_mem.cpu_addr;
419 	return (0);
420 }
421 
422 static void
423 gve_free_counter_array(struct gve_priv *priv)
424 {
425 	if (priv->counters != NULL)
426 		gve_dma_free_coherent(&priv->counter_array_mem);
427 	priv->counter_array_mem = (struct gve_dma_handle){};
428 }
429 
430 static int
431 gve_alloc_irq_db_array(struct gve_priv *priv)
432 {
433 	int err;
434 
435 	err = gve_dma_alloc_coherent(priv,
436 	    sizeof(struct gve_irq_db) * (priv->num_queues), PAGE_SIZE,
437 	    &priv->irqs_db_mem);
438 	if (err != 0)
439 		return (err);
440 
441 	priv->irq_db_indices = priv->irqs_db_mem.cpu_addr;
442 	return (0);
443 }
444 
445 static void
446 gve_free_irq_db_array(struct gve_priv *priv)
447 {
448 	if (priv->irq_db_indices != NULL)
449 		gve_dma_free_coherent(&priv->irqs_db_mem);
450 	priv->irqs_db_mem = (struct gve_dma_handle){};
451 }
452 
453 static void
454 gve_free_rings(struct gve_priv *priv)
455 {
456 	gve_free_irqs(priv);
457 	gve_free_tx_rings(priv);
458 	gve_free_rx_rings(priv);
459 	gve_free_qpls(priv);
460 }
461 
462 static int
463 gve_alloc_rings(struct gve_priv *priv)
464 {
465 	int err;
466 
467 	err = gve_alloc_qpls(priv);
468 	if (err != 0)
469 		goto abort;
470 
471 	err = gve_alloc_rx_rings(priv);
472 	if (err != 0)
473 		goto abort;
474 
475 	err = gve_alloc_tx_rings(priv);
476 	if (err != 0)
477 		goto abort;
478 
479 	err = gve_alloc_irqs(priv);
480 	if (err != 0)
481 		goto abort;
482 
483 	return (0);
484 
485 abort:
486 	gve_free_rings(priv);
487 	return (err);
488 }
489 
490 static void
491 gve_deconfigure_resources(struct gve_priv *priv)
492 {
493 	int err;
494 
495 	if (gve_get_state_flag(priv, GVE_STATE_FLAG_RESOURCES_OK)) {
496 		err = gve_adminq_deconfigure_device_resources(priv);
497 		if (err != 0) {
498 			device_printf(priv->dev, "Failed to deconfigure device resources: err=%d\n",
499 			    err);
500 			return;
501 		}
502 		if (bootverbose)
503 			device_printf(priv->dev, "Deconfigured device resources\n");
504 		gve_clear_state_flag(priv, GVE_STATE_FLAG_RESOURCES_OK);
505 	}
506 
507 	gve_free_irq_db_array(priv);
508 	gve_free_counter_array(priv);
509 }
510 
511 static int
512 gve_configure_resources(struct gve_priv *priv)
513 {
514 	int err;
515 
516 	if (gve_get_state_flag(priv, GVE_STATE_FLAG_RESOURCES_OK))
517 		return (0);
518 
519 	err = gve_alloc_counter_array(priv);
520 	if (err != 0)
521 		return (err);
522 
523 	err = gve_alloc_irq_db_array(priv);
524 	if (err != 0)
525 		goto abort;
526 
527 	err = gve_adminq_configure_device_resources(priv);
528 	if (err != 0) {
529 		device_printf(priv->dev, "Failed to configure device resources: err=%d\n",
530 			      err);
531 		err = (ENXIO);
532 		goto abort;
533 	}
534 
535 	gve_set_state_flag(priv, GVE_STATE_FLAG_RESOURCES_OK);
536 	if (bootverbose)
537 		device_printf(priv->dev, "Configured device resources\n");
538 	return (0);
539 
540 abort:
541 	gve_deconfigure_resources(priv);
542 	return (err);
543 }
544 
545 static void
546 gve_set_queue_cnts(struct gve_priv *priv)
547 {
548 	priv->tx_cfg.max_queues = gve_reg_bar_read_4(priv, MAX_TX_QUEUES);
549 	priv->rx_cfg.max_queues = gve_reg_bar_read_4(priv, MAX_RX_QUEUES);
550 	priv->tx_cfg.num_queues = priv->tx_cfg.max_queues;
551 	priv->rx_cfg.num_queues = priv->rx_cfg.max_queues;
552 
553 	if (priv->default_num_queues > 0) {
554 		priv->tx_cfg.num_queues = MIN(priv->default_num_queues,
555 		    priv->tx_cfg.num_queues);
556 		priv->rx_cfg.num_queues = MIN(priv->default_num_queues,
557 		    priv->rx_cfg.num_queues);
558 	}
559 
560 	priv->num_queues = priv->tx_cfg.num_queues + priv->rx_cfg.num_queues;
561 	priv->mgmt_msix_idx = priv->num_queues;
562 }
563 
564 static int
565 gve_alloc_adminq_and_describe_device(struct gve_priv *priv)
566 {
567 	int err;
568 
569 	if ((err = gve_adminq_alloc(priv)) != 0)
570 		return (err);
571 
572 	if ((err = gve_verify_driver_compatibility(priv)) != 0) {
573 		device_printf(priv->dev,
574 		    "Failed to verify driver compatibility: err=%d\n", err);
575 		goto abort;
576 	}
577 
578 	if ((err = gve_adminq_describe_device(priv)) != 0)
579 		goto abort;
580 
581 	gve_set_queue_cnts(priv);
582 
583 	priv->num_registered_pages = 0;
584 	return (0);
585 
586 abort:
587 	gve_release_adminq(priv);
588 	return (err);
589 }
590 
591 void
592 gve_schedule_reset(struct gve_priv *priv)
593 {
594 	if (gve_get_state_flag(priv, GVE_STATE_FLAG_IN_RESET))
595 		return;
596 
597 	device_printf(priv->dev, "Scheduling reset task!\n");
598 	gve_set_state_flag(priv, GVE_STATE_FLAG_DO_RESET);
599 	taskqueue_enqueue(priv->service_tq, &priv->service_task);
600 }
601 
602 static void
603 gve_destroy(struct gve_priv *priv)
604 {
605 	gve_down(priv);
606 	gve_deconfigure_resources(priv);
607 	gve_release_adminq(priv);
608 }
609 
610 static void
611 gve_restore(struct gve_priv *priv)
612 {
613 	int err;
614 
615 	err = gve_adminq_alloc(priv);
616 	if (err != 0)
617 		goto abort;
618 
619 	err = gve_configure_resources(priv);
620 	if (err != 0)
621 		goto abort;
622 
623 	err = gve_up(priv);
624 	if (err != 0)
625 		goto abort;
626 
627 	return;
628 
629 abort:
630 	device_printf(priv->dev, "Restore failed!\n");
631 	return;
632 }
633 
634 static void
635 gve_handle_reset(struct gve_priv *priv)
636 {
637 	if (!gve_get_state_flag(priv, GVE_STATE_FLAG_DO_RESET))
638 		return;
639 
640 	gve_clear_state_flag(priv, GVE_STATE_FLAG_DO_RESET);
641 	gve_set_state_flag(priv, GVE_STATE_FLAG_IN_RESET);
642 
643 	GVE_IFACE_LOCK_LOCK(priv->gve_iface_lock);
644 
645 	if_setdrvflagbits(priv->ifp, IFF_DRV_OACTIVE, IFF_DRV_RUNNING);
646 	if_link_state_change(priv->ifp, LINK_STATE_DOWN);
647 	gve_clear_state_flag(priv, GVE_STATE_FLAG_LINK_UP);
648 
649 	/*
650 	 * Releasing the adminq causes the NIC to destroy all resources
651 	 * registered with it, so by clearing the flags beneath we cause
652 	 * the subsequent gve_down call below to not attempt to tell the
653 	 * NIC to destroy these resources again.
654 	 *
655 	 * The call to gve_down is needed in the first place to refresh
656 	 * the state and the DMA-able memory within each driver ring.
657 	 */
658 	gve_release_adminq(priv);
659 	gve_clear_state_flag(priv, GVE_STATE_FLAG_RESOURCES_OK);
660 	gve_clear_state_flag(priv, GVE_STATE_FLAG_QPLREG_OK);
661 	gve_clear_state_flag(priv, GVE_STATE_FLAG_RX_RINGS_OK);
662 	gve_clear_state_flag(priv, GVE_STATE_FLAG_TX_RINGS_OK);
663 
664 	gve_down(priv);
665 	gve_restore(priv);
666 
667 	GVE_IFACE_LOCK_UNLOCK(priv->gve_iface_lock);
668 
669 	priv->reset_cnt++;
670 	gve_clear_state_flag(priv, GVE_STATE_FLAG_IN_RESET);
671 }
672 
673 static void
674 gve_handle_link_status(struct gve_priv *priv)
675 {
676 	uint32_t status = gve_reg_bar_read_4(priv, DEVICE_STATUS);
677 	bool link_up = status & GVE_DEVICE_STATUS_LINK_STATUS;
678 
679 	if (link_up == gve_get_state_flag(priv, GVE_STATE_FLAG_LINK_UP))
680 		return;
681 
682 	if (link_up) {
683 		if (bootverbose)
684 			device_printf(priv->dev, "Device link is up.\n");
685 		if_link_state_change(priv->ifp, LINK_STATE_UP);
686 		gve_set_state_flag(priv, GVE_STATE_FLAG_LINK_UP);
687 	} else {
688 		device_printf(priv->dev, "Device link is down.\n");
689 		if_link_state_change(priv->ifp, LINK_STATE_DOWN);
690 		gve_clear_state_flag(priv, GVE_STATE_FLAG_LINK_UP);
691 	}
692 }
693 
694 static void
695 gve_service_task(void *arg, int pending)
696 {
697 	struct gve_priv *priv = (struct gve_priv *)arg;
698 	uint32_t status = gve_reg_bar_read_4(priv, DEVICE_STATUS);
699 
700 	if (((GVE_DEVICE_STATUS_RESET_MASK & status) != 0) &&
701 	    !gve_get_state_flag(priv, GVE_STATE_FLAG_IN_RESET)) {
702 		device_printf(priv->dev, "Device requested reset\n");
703 		gve_set_state_flag(priv, GVE_STATE_FLAG_DO_RESET);
704 	}
705 
706 	gve_handle_reset(priv);
707 	gve_handle_link_status(priv);
708 }
709 
710 static int
711 gve_probe(device_t dev)
712 {
713 	uint16_t deviceid, vendorid;
714 	int i;
715 
716 	vendorid = pci_get_vendor(dev);
717 	deviceid = pci_get_device(dev);
718 
719 	for (i = 0; i < nitems(gve_devs); i++) {
720 		if (vendorid == gve_devs[i].vendor_id &&
721 		    deviceid == gve_devs[i].device_id) {
722 			device_set_desc(dev, gve_devs[i].name);
723 			return (BUS_PROBE_DEFAULT);
724 		}
725 	}
726 	return (ENXIO);
727 }
728 
729 static void
730 gve_free_sys_res_mem(struct gve_priv *priv)
731 {
732 	if (priv->msix_table != NULL)
733 		bus_release_resource(priv->dev, SYS_RES_MEMORY,
734 		    rman_get_rid(priv->msix_table), priv->msix_table);
735 
736 	if (priv->db_bar != NULL)
737 		bus_release_resource(priv->dev, SYS_RES_MEMORY,
738 		    rman_get_rid(priv->db_bar), priv->db_bar);
739 
740 	if (priv->reg_bar != NULL)
741 		bus_release_resource(priv->dev, SYS_RES_MEMORY,
742 		    rman_get_rid(priv->reg_bar), priv->reg_bar);
743 }
744 
745 static int
746 gve_attach(device_t dev)
747 {
748 	struct gve_priv *priv;
749 	int rid;
750 	int err;
751 
752 	priv = device_get_softc(dev);
753 	priv->dev = dev;
754 	GVE_IFACE_LOCK_INIT(priv->gve_iface_lock);
755 
756 	pci_enable_busmaster(dev);
757 
758 	rid = PCIR_BAR(GVE_REGISTER_BAR);
759 	priv->reg_bar = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
760 	    &rid, RF_ACTIVE);
761 	if (priv->reg_bar == NULL) {
762 		device_printf(dev, "Failed to allocate BAR0\n");
763 		err = ENXIO;
764 		goto abort;
765 	}
766 
767 	rid = PCIR_BAR(GVE_DOORBELL_BAR);
768 	priv->db_bar = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
769 	    &rid, RF_ACTIVE);
770 	if (priv->db_bar == NULL) {
771 		device_printf(dev, "Failed to allocate BAR2\n");
772 		err = ENXIO;
773 		goto abort;
774 	}
775 
776 	rid = pci_msix_table_bar(priv->dev);
777 	priv->msix_table = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
778 	    &rid, RF_ACTIVE);
779 	if (priv->msix_table == NULL) {
780 		device_printf(dev, "Failed to allocate msix table\n");
781 		err = ENXIO;
782 		goto abort;
783 	}
784 
785 	err = gve_alloc_adminq_and_describe_device(priv);
786 	if (err != 0)
787 		goto abort;
788 
789 	err = gve_configure_resources(priv);
790 	if (err != 0)
791 		goto abort;
792 
793 	err = gve_alloc_rings(priv);
794 	if (err != 0)
795 		goto abort;
796 
797 	err = gve_setup_ifnet(dev, priv);
798 	if (err != 0)
799 		goto abort;
800 
801 	priv->rx_copybreak = GVE_DEFAULT_RX_COPYBREAK;
802 
803 	bus_write_multi_1(priv->reg_bar, DRIVER_VERSION, GVE_DRIVER_VERSION,
804 	    sizeof(GVE_DRIVER_VERSION) - 1);
805 
806 	TASK_INIT(&priv->service_task, 0, gve_service_task, priv);
807 	priv->service_tq = taskqueue_create("gve service", M_WAITOK | M_ZERO,
808 	    taskqueue_thread_enqueue, &priv->service_tq);
809 	taskqueue_start_threads(&priv->service_tq, 1, PI_NET, "%s service tq",
810 	    device_get_nameunit(priv->dev));
811 
812         gve_setup_sysctl(priv);
813 
814 	if (bootverbose)
815 		device_printf(priv->dev, "Successfully attached %s", GVE_DRIVER_VERSION);
816 	return (0);
817 
818 abort:
819 	gve_free_rings(priv);
820 	gve_deconfigure_resources(priv);
821 	gve_release_adminq(priv);
822 	gve_free_sys_res_mem(priv);
823 	GVE_IFACE_LOCK_DESTROY(priv->gve_iface_lock);
824 	return (err);
825 }
826 
827 static int
828 gve_detach(device_t dev)
829 {
830 	struct gve_priv *priv = device_get_softc(dev);
831 	if_t ifp = priv->ifp;
832 
833 	ether_ifdetach(ifp);
834 
835 	GVE_IFACE_LOCK_LOCK(priv->gve_iface_lock);
836 	gve_destroy(priv);
837 	GVE_IFACE_LOCK_UNLOCK(priv->gve_iface_lock);
838 
839 	gve_free_rings(priv);
840 	gve_free_sys_res_mem(priv);
841 	GVE_IFACE_LOCK_DESTROY(priv->gve_iface_lock);
842 
843 	while (taskqueue_cancel(priv->service_tq, &priv->service_task, NULL))
844 		taskqueue_drain(priv->service_tq, &priv->service_task);
845 	taskqueue_free(priv->service_tq);
846 
847 	if_free(ifp);
848 	return (bus_generic_detach(dev));
849 }
850 
851 static device_method_t gve_methods[] = {
852 	DEVMETHOD(device_probe, gve_probe),
853 	DEVMETHOD(device_attach, gve_attach),
854 	DEVMETHOD(device_detach, gve_detach),
855 	DEVMETHOD_END
856 };
857 
858 static driver_t gve_driver = {
859 	"gve",
860 	gve_methods,
861 	sizeof(struct gve_priv)
862 };
863 
864 #if __FreeBSD_version < 1301503
865 static devclass_t gve_devclass;
866 
867 DRIVER_MODULE(gve, pci, gve_driver, gve_devclass, 0, 0);
868 #else
869 DRIVER_MODULE(gve, pci, gve_driver, 0, 0);
870 #endif
871 MODULE_PNP_INFO("U16:vendor;U16:device;D:#", pci, gve, gve_devs,
872     nitems(gve_devs));
873