xref: /openbsd-src/sys/dev/pv/hyperv.c (revision 03adc85b7600a1f8f04886b8321c1c1c0c4933d4)
1 /*-
2  * Copyright (c) 2009-2012 Microsoft Corp.
3  * Copyright (c) 2012 NetApp Inc.
4  * Copyright (c) 2012 Citrix Inc.
5  * Copyright (c) 2016 Mike Belopuhov <mike@esdenera.com>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice unmodified, this list of conditions, and the following
13  *    disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * The OpenBSD port was done under funding by Esdenera Networks GmbH.
32  */
33 
34 #include <sys/param.h>
35 
36 /* Hyperv requires locked atomic operations */
37 #ifndef MULTIPROCESSOR
38 #define _HYPERVMPATOMICS
39 #define MULTIPROCESSOR
40 #endif
41 #include <sys/atomic.h>
42 #ifdef _HYPERVMPATOMICS
43 #undef MULTIPROCESSOR
44 #undef _HYPERVMPATOMICS
45 #endif
46 
47 #include <sys/systm.h>
48 #include <sys/proc.h>
49 #include <sys/signal.h>
50 #include <sys/signalvar.h>
51 #include <sys/malloc.h>
52 #include <sys/kernel.h>
53 #include <sys/device.h>
54 #include <sys/timetc.h>
55 #include <sys/task.h>
56 #include <sys/syslog.h>
57 
58 #include <machine/bus.h>
59 #include <machine/cpu.h>
60 #include <machine/cpufunc.h>
61 
62 #include <uvm/uvm_extern.h>
63 
64 #include <machine/i82489var.h>
65 
66 #include <dev/rndvar.h>
67 
68 #include <dev/pv/pvvar.h>
69 #include <dev/pv/pvreg.h>
70 #include <dev/pv/hypervreg.h>
71 #include <dev/pv/hypervvar.h>
72 
73 /* Command submission flags */
74 #define HCF_SLEEPOK	0x0001	/* M_WAITOK */
75 #define HCF_NOSLEEP	0x0002	/* M_NOWAIT */
76 #define HCF_NOREPLY	0x0004
77 
78 struct hv_softc *hv_sc;
79 
80 int 	hv_match(struct device *, void *, void *);
81 void	hv_attach(struct device *, struct device *, void *);
82 void	hv_deferred(void *);
83 void	hv_set_version(struct hv_softc *);
84 u_int	hv_gettime(struct timecounter *);
85 int	hv_init_hypercall(struct hv_softc *);
86 uint64_t hv_hypercall(struct hv_softc *, uint64_t, void *, void *);
87 int	hv_init_interrupts(struct hv_softc *);
88 int	hv_init_synic(struct hv_softc *);
89 int	hv_cmd(struct hv_softc *, void *, size_t, void *, size_t, int);
90 int	hv_start(struct hv_softc *, struct hv_msg *);
91 int	hv_reply(struct hv_softc *, struct hv_msg *);
92 void	hv_wait(struct hv_softc *, int (*done)(struct hv_softc *,
93 	    struct hv_msg *), struct hv_msg *, void *, const char *);
94 uint16_t hv_intr_signal(struct hv_softc *, void *);
95 void	hv_intr(void);
96 void	hv_event_intr(struct hv_softc *);
97 void	hv_message_intr(struct hv_softc *);
98 int	hv_vmbus_connect(struct hv_softc *);
99 void	hv_channel_response(struct hv_softc *, struct vmbus_chanmsg_hdr *);
100 void	hv_channel_offer(struct hv_softc *, struct vmbus_chanmsg_hdr *);
101 void	hv_channel_delivered(struct hv_softc *, struct vmbus_chanmsg_hdr *);
102 int	hv_channel_scan(struct hv_softc *);
103 void	hv_process_offer(struct hv_softc *, struct hv_offer *);
104 struct hv_channel *
105 	hv_channel_lookup(struct hv_softc *, uint32_t);
106 int	hv_channel_ring_create(struct hv_channel *, uint32_t);
107 void	hv_channel_ring_destroy(struct hv_channel *);
108 extern void hv_attach_icdevs(struct hv_softc *);
109 int	hv_attach_devices(struct hv_softc *);
110 
111 struct {
112 	int		  hmd_response;
113 	int		  hmd_request;
114 	void		(*hmd_handler)(struct hv_softc *,
115 			    struct vmbus_chanmsg_hdr *);
116 } hv_msg_dispatch[] = {
117 	{ 0,					0, NULL },
118 	{ VMBUS_CHANMSG_CHOFFER,		0, hv_channel_offer },
119 	{ VMBUS_CHANMSG_CHRESCIND,		0, NULL },
120 	{ VMBUS_CHANMSG_CHREQUEST,		VMBUS_CHANMSG_CHOFFER,
121 	  NULL },
122 	{ VMBUS_CHANMSG_CHOFFER_DONE,		0,
123 	  hv_channel_delivered },
124 	{ VMBUS_CHANMSG_CHOPEN,			0, NULL },
125 	{ VMBUS_CHANMSG_CHOPEN_RESP,		VMBUS_CHANMSG_CHOPEN,
126 	  hv_channel_response },
127 	{ VMBUS_CHANMSG_CHCLOSE,		0, NULL },
128 	{ VMBUS_CHANMSG_GPADL_CONN,		0, NULL },
129 	{ VMBUS_CHANMSG_GPADL_SUBCONN,		0, NULL },
130 	{ VMBUS_CHANMSG_GPADL_CONNRESP,		VMBUS_CHANMSG_GPADL_CONN,
131 	  hv_channel_response },
132 	{ VMBUS_CHANMSG_GPADL_DISCONN,		0, NULL },
133 	{ VMBUS_CHANMSG_GPADL_DISCONNRESP,	VMBUS_CHANMSG_GPADL_DISCONN,
134 	  hv_channel_response },
135 	{ VMBUS_CHANMSG_CHFREE,			0, NULL },
136 	{ VMBUS_CHANMSG_CONNECT,		0, NULL },
137 	{ VMBUS_CHANMSG_CONNECT_RESP,		VMBUS_CHANMSG_CONNECT,
138 	  hv_channel_response },
139 	{ VMBUS_CHANMSG_DISCONNECT,		0, NULL },
140 };
141 
142 struct timecounter hv_timecounter = {
143 	hv_gettime, 0, 0xffffffff, 10000000, "hyperv", 9001
144 };
145 
146 struct cfdriver hyperv_cd = {
147 	NULL, "hyperv", DV_DULL
148 };
149 
150 const struct cfattach hyperv_ca = {
151 	sizeof(struct hv_softc), hv_match, hv_attach
152 };
153 
154 const struct hv_guid hv_guid_network = {
155 	{ 0x63, 0x51, 0x61, 0xf8, 0x3e, 0xdf, 0xc5, 0x46,
156 	  0x91, 0x3f, 0xf2, 0xd2, 0xf9, 0x65, 0xed, 0x0e }
157 };
158 
159 const struct hv_guid hv_guid_ide = {
160 	{ 0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
161 	  0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5 }
162 };
163 
164 const struct hv_guid hv_guid_scsi = {
165 	{ 0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
166 	  0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f }
167 };
168 
169 const struct hv_guid hv_guid_shutdown = {
170 	{ 0x31, 0x60, 0x0b, 0x0e, 0x13, 0x52, 0x34, 0x49,
171 	  0x81, 0x8b, 0x38, 0xd9, 0x0c, 0xed, 0x39, 0xdb }
172 };
173 
174 const struct hv_guid hv_guid_timesync = {
175 	{ 0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
176 	  0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf }
177 };
178 
179 const struct hv_guid hv_guid_heartbeat = {
180 	{ 0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
181 	  0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d }
182 };
183 
184 const struct hv_guid hv_guid_kvp = {
185 	{ 0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
186 	  0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x03, 0xe6 }
187 };
188 
189 #ifdef HYPERV_DEBUG
190 const struct hv_guid hv_guid_vss = {
191 	{ 0x29, 0x2e, 0xfa, 0x35, 0x23, 0xea, 0x36, 0x42,
192 	  0x96, 0xae, 0x3a, 0x6e, 0xba, 0xcb, 0xa4, 0x40 }
193 };
194 
195 const struct hv_guid hv_guid_dynmem = {
196 	{ 0xdc, 0x74, 0x50, 0x52, 0x85, 0x89, 0xe2, 0x46,
197 	  0x80, 0x57, 0xa3, 0x07, 0xdc, 0x18, 0xa5, 0x02 }
198 };
199 
200 const struct hv_guid hv_guid_mouse = {
201 	{ 0x9e, 0xb6, 0xa8, 0xcf, 0x4a, 0x5b, 0xc0, 0x4c,
202 	  0xb9, 0x8b, 0x8b, 0xa1, 0xa1, 0xf3, 0xf9, 0x5a }
203 };
204 
205 const struct hv_guid hv_guid_kbd = {
206 	{ 0x6d, 0xad, 0x12, 0xf9, 0x17, 0x2b, 0xea, 0x48,
207 	  0xbd, 0x65, 0xf9, 0x27, 0xa6, 0x1c, 0x76, 0x84 }
208 };
209 
210 const struct hv_guid hv_guid_video = {
211 	{ 0x02, 0x78, 0x0a, 0xda, 0x77, 0xe3, 0xac, 0x4a,
212 	  0x8e, 0x77, 0x05, 0x58, 0xeb, 0x10, 0x73, 0xf8 }
213 };
214 
215 const struct hv_guid hv_guid_fc = {
216 	{ 0x4a, 0xcc, 0x9b, 0x2f, 0x69, 0x00, 0xf3, 0x4a,
217 	  0xb7, 0x6b, 0x6f, 0xd0, 0xbe, 0x52, 0x8c, 0xda }
218 };
219 
220 const struct hv_guid hv_guid_fcopy = {
221 	{ 0xe3, 0x4b, 0xd1, 0x34, 0xe4, 0xde, 0xc8, 0x41,
222 	  0x9a, 0xe7, 0x6b, 0x17, 0x49, 0x77, 0xc1, 0x92 }
223 };
224 
225 const struct hv_guid hv_guid_pcie = {
226 	{ 0x1d, 0xf6, 0xc4, 0x44, 0x44, 0x44, 0x00, 0x44,
227 	  0x9d, 0x52, 0x80, 0x2e, 0x27, 0xed, 0xe1, 0x9f }
228 };
229 
230 const struct hv_guid hv_guid_netdir = {
231 	{ 0x3d, 0xaf, 0x2e, 0x8c, 0xa7, 0x32, 0x09, 0x4b,
232 	  0xab, 0x99, 0xbd, 0x1f, 0x1c, 0x86, 0xb5, 0x01 }
233 };
234 
235 const struct hv_guid hv_guid_rdesktop = {
236 	{ 0xf4, 0xac, 0x6a, 0x27, 0x15, 0xac, 0x6c, 0x42,
237 	  0x98, 0xdd, 0x75, 0x21, 0xad, 0x3f, 0x01, 0xfe }
238 };
239 
240 /* Automatic Virtual Machine Activation (AVMA) Services */
241 const struct hv_guid hv_guid_avma1 = {
242 	{ 0x55, 0xb2, 0x87, 0x44, 0x8c, 0xb8, 0x3f, 0x40,
243 	  0xbb, 0x51, 0xd1, 0xf6, 0x9c, 0xf1, 0x7f, 0x87 }
244 };
245 
246 const struct hv_guid hv_guid_avma2 = {
247 	{ 0xf4, 0xba, 0x75, 0x33, 0x15, 0x9e, 0x30, 0x4b,
248 	  0xb7, 0x65, 0x67, 0xac, 0xb1, 0x0d, 0x60, 0x7b }
249 };
250 
251 const struct hv_guid hv_guid_avma3 = {
252 	{ 0xa0, 0x1f, 0x22, 0x99, 0xad, 0x24, 0xe2, 0x11,
253 	  0xbe, 0x98, 0x00, 0x1a, 0xa0, 0x1b, 0xbf, 0x6e }
254 };
255 
256 const struct hv_guid hv_guid_avma4 = {
257 	{ 0x16, 0x57, 0xe6, 0xf8, 0xb3, 0x3c, 0x06, 0x4a,
258 	  0x9a, 0x60, 0x18, 0x89, 0xc5, 0xcc, 0xca, 0xb5 }
259 };
260 #endif	/* HYPERV_DEBUG */
261 
262 int
263 hv_match(struct device *parent, void *match, void *aux)
264 {
265 	struct pv_attach_args *pva = aux;
266 	struct pvbus_hv *hv = &pva->pva_hv[PVBUS_HYPERV];
267 
268 	if ((hv->hv_major == 0 && hv->hv_minor == 0) || hv->hv_base == 0)
269 		return (0);
270 
271 	return (1);
272 }
273 
274 void
275 hv_attach(struct device *parent, struct device *self, void *aux)
276 {
277 	struct hv_softc *sc = (struct hv_softc *)self;
278 	struct pv_attach_args *pva = aux;
279 	struct pvbus_hv *hv = &pva->pva_hv[PVBUS_HYPERV];
280 
281 	sc->sc_pvbus = hv;
282 	sc->sc_dmat = pva->pva_dmat;
283 
284 	if (!(hv->hv_features & CPUID_HV_MSR_HYPERCALL) ||
285 	    !(hv->hv_features & CPUID_HV_MSR_SYNIC)) {
286 		printf(": not functional\n");
287 		return;
288 	}
289 
290 	DPRINTF("\n");
291 
292 	hv_set_version(sc);
293 
294 	if (hv->hv_features & CPUID_HV_MSR_TIME_REFCNT)
295 		tc_init(&hv_timecounter);
296 
297 	if (hv_init_hypercall(sc))
298 		return;
299 
300 	/* Wire it up to the global */
301 	hv_sc = sc;
302 
303 	if (hv_init_interrupts(sc))
304 		return;
305 
306 	if (hv_vmbus_connect(sc))
307 		return;
308 
309 	DPRINTF("%s", sc->sc_dev.dv_xname);
310 	printf(": protocol %d.%d, features %#x\n",
311 	    VMBUS_VERSION_MAJOR(sc->sc_proto),
312 	    VMBUS_VERSION_MINOR(sc->sc_proto),
313 	    hv->hv_features);
314 
315 	if (hv_channel_scan(sc))
316 		return;
317 
318 	/* Attach heartbeat, KVP and other "internal" services */
319 	hv_attach_icdevs(sc);
320 
321 	startuphook_establish(hv_deferred, sc);
322 }
323 
324 void
325 hv_deferred(void *arg)
326 {
327 	struct hv_softc *sc = arg;
328 
329 	if (hv_attach_devices(sc))
330 		return;
331 }
332 
333 void
334 hv_set_version(struct hv_softc *sc)
335 {
336 	uint64_t ver;
337 
338 	/* OpenBSD build date */
339 	ver = MSR_HV_GUESTID_OSTYPE_OPENBSD;
340 	ver |= (uint64_t)OpenBSD << MSR_HV_GUESTID_VERSION_SHIFT;
341 	wrmsr(MSR_HV_GUEST_OS_ID, ver);
342 }
343 
344 u_int
345 hv_gettime(struct timecounter *tc)
346 {
347 	u_int now = rdmsr(MSR_HV_TIME_REF_COUNT);
348 
349 	return (now);
350 }
351 
352 int
353 hv_init_hypercall(struct hv_softc *sc)
354 {
355 	extern void *hv_hypercall_page;
356 	uint64_t msr;
357 	paddr_t pa;
358 
359 	sc->sc_hc = &hv_hypercall_page;
360 
361 	if (!pmap_extract(pmap_kernel(), (vaddr_t)sc->sc_hc, &pa)) {
362 		printf(": hypercall page PA extraction failed\n");
363 		return (-1);
364 	}
365 
366 	msr = (atop(pa) << MSR_HV_HYPERCALL_PGSHIFT) | MSR_HV_HYPERCALL_ENABLE;
367 	wrmsr(MSR_HV_HYPERCALL, msr);
368 
369 	if (!(rdmsr(MSR_HV_HYPERCALL) & MSR_HV_HYPERCALL_ENABLE)) {
370 		printf(": failed to set up a hypercall page\n");
371 		return (-1);
372 	}
373 
374 	return (0);
375 }
376 
377 uint64_t
378 hv_hypercall(struct hv_softc *sc, uint64_t control, void *input,
379     void *output)
380 {
381 	paddr_t input_pa = 0, output_pa = 0;
382 	uint64_t status = 0;
383 
384 	if (input != NULL &&
385 	    pmap_extract(pmap_kernel(), (vaddr_t)input, &input_pa) == 0) {
386 		printf("%s: hypercall input PA extraction failed\n",
387 		    sc->sc_dev.dv_xname);
388 		return (~HYPERCALL_STATUS_SUCCESS);
389 	}
390 
391 	if (output != NULL &&
392 	    pmap_extract(pmap_kernel(), (vaddr_t)output, &output_pa) == 0) {
393 		printf("%s: hypercall output PA extraction failed\n",
394 		    sc->sc_dev.dv_xname);
395 		return (~HYPERCALL_STATUS_SUCCESS);
396 	}
397 
398 #ifdef __amd64__
399 	__asm__ __volatile__ ("mov %0, %%r8" : : "r" (output_pa) : "r8");
400 	__asm__ __volatile__ ("call *%3" : "=a" (status) : "c" (control),
401 	    "d" (input_pa), "m" (sc->sc_hc));
402 #else  /* __i386__ */
403 	{
404 		uint32_t control_hi = control >> 32;
405 		uint32_t control_lo = control & 0xfffffffff;
406 		uint32_t status_hi = 1;
407 		uint32_t status_lo = 1;
408 
409 		__asm__ __volatile__ ("call *%8" :
410 		    "=d" (status_hi), "=a"(status_lo) :
411 		    "d" (control_hi), "a" (control_lo),
412 		    "b" (0), "c" (input_pa), "D" (0), "S" (output_pa),
413 		    "m" (sc->sc_hc));
414 
415 		status = status_lo | ((uint64_t)status_hi << 32);
416 	}
417 #endif	/* __amd64__ */
418 
419 	return (status);
420 }
421 
422 int
423 hv_init_interrupts(struct hv_softc *sc)
424 {
425 	struct cpu_info *ci = curcpu();
426 	int cpu = CPU_INFO_UNIT(ci);
427 
428 	sc->sc_idtvec = LAPIC_HYPERV_VECTOR;
429 
430 	TAILQ_INIT(&sc->sc_reqs);
431 	mtx_init(&sc->sc_reqlck, IPL_NET);
432 
433 	TAILQ_INIT(&sc->sc_rsps);
434 	mtx_init(&sc->sc_rsplck, IPL_NET);
435 
436 	sc->sc_simp[cpu] = km_alloc(PAGE_SIZE, &kv_any, &kp_zero, &kd_nowait);
437 	if (sc->sc_simp[cpu] == NULL) {
438 		printf(": failed to allocate SIMP\n");
439 		return (-1);
440 	}
441 
442 	sc->sc_siep[cpu] = km_alloc(PAGE_SIZE, &kv_any, &kp_zero, &kd_nowait);
443 	if (sc->sc_siep[cpu] == NULL) {
444 		printf(": failed to allocate SIEP\n");
445 		km_free(sc->sc_simp[cpu], PAGE_SIZE, &kv_any, &kp_zero);
446 		return (-1);
447 	}
448 
449 	sc->sc_proto = VMBUS_VERSION_WS2008;
450 
451 	return (hv_init_synic(sc));
452 }
453 
454 int
455 hv_init_synic(struct hv_softc *sc)
456 {
457 	struct cpu_info *ci = curcpu();
458 	int cpu = CPU_INFO_UNIT(ci);
459 	uint64_t simp, siefp, sctrl, sint;
460 	paddr_t pa;
461 
462 	/*
463 	 * Setup the Synic's message page
464 	 */
465 	if (!pmap_extract(pmap_kernel(), (vaddr_t)sc->sc_simp[cpu], &pa)) {
466 		printf(": SIMP PA extraction failed\n");
467 		return (-1);
468 	}
469 	simp = rdmsr(MSR_HV_SIMP);
470 	simp &= (1 << MSR_HV_SIMP_PGSHIFT) - 1;
471 	simp |= (atop(pa) << MSR_HV_SIMP_PGSHIFT);
472 	simp |= MSR_HV_SIMP_ENABLE;
473 	wrmsr(MSR_HV_SIMP, simp);
474 
475 	/*
476 	 * Setup the Synic's event page
477 	 */
478 	if (!pmap_extract(pmap_kernel(), (vaddr_t)sc->sc_siep[cpu], &pa)) {
479 		printf(": SIEP PA extraction failed\n");
480 		return (-1);
481 	}
482 	siefp = rdmsr(MSR_HV_SIEFP);
483 	siefp &= (1<<MSR_HV_SIEFP_PGSHIFT) - 1;
484 	siefp |= (atop(pa) << MSR_HV_SIEFP_PGSHIFT);
485 	siefp |= MSR_HV_SIEFP_ENABLE;
486 	wrmsr(MSR_HV_SIEFP, siefp);
487 
488 	/*
489 	 * Configure and unmask SINT for message and event flags
490 	 */
491 	sint = rdmsr(MSR_HV_SINT0 + VMBUS_SINT_MESSAGE);
492 	sint = sc->sc_idtvec | MSR_HV_SINT_AUTOEOI |
493 	    (sint & MSR_HV_SINT_RSVD_MASK);
494 	wrmsr(MSR_HV_SINT0 + VMBUS_SINT_MESSAGE, sint);
495 
496 	/* Enable the global synic bit */
497 	sctrl = rdmsr(MSR_HV_SCONTROL);
498 	sctrl |= MSR_HV_SCTRL_ENABLE;
499 	wrmsr(MSR_HV_SCONTROL, sctrl);
500 
501 	sc->sc_vcpus[cpu] = rdmsr(MSR_HV_VP_INDEX);
502 
503 	DPRINTF("vcpu%u: SIMP %#llx SIEFP %#llx SCTRL %#llx\n",
504 	    sc->sc_vcpus[cpu], simp, siefp, sctrl);
505 
506 	return (0);
507 }
508 
509 int
510 hv_cmd(struct hv_softc *sc, void *cmd, size_t cmdlen, void *rsp,
511     size_t rsplen, int flags)
512 {
513 	struct hv_msg msg;
514 	int rv;
515 
516 	if (cmdlen > VMBUS_MSG_DSIZE_MAX) {
517 		printf("%s: payload too large (%lu)\n", sc->sc_dev.dv_xname,
518 		    cmdlen);
519 		return (EMSGSIZE);
520 	}
521 
522 	memset(&msg, 0, sizeof(msg));
523 
524 	msg.msg_req.hc_dsize = cmdlen;
525 	memcpy(msg.msg_req.hc_data, cmd, cmdlen);
526 
527 	if (!(flags & HCF_NOREPLY)) {
528 		msg.msg_rsp = rsp;
529 		msg.msg_rsplen = rsplen;
530 	} else
531 		msg.msg_flags |= MSGF_NOQUEUE;
532 
533 	if (flags & HCF_NOSLEEP)
534 		msg.msg_flags |= MSGF_NOSLEEP;
535 
536 	if ((rv = hv_start(sc, &msg)) != 0)
537 		return (rv);
538 	return (hv_reply(sc, &msg));
539 }
540 
541 int
542 hv_start(struct hv_softc *sc, struct hv_msg *msg)
543 {
544 	const int delays[] = { 100, 100, 100, 500, 500, 5000, 5000, 5000 };
545 	const char *wchan = "hvstart";
546 	uint16_t status;
547 	int i, s;
548 
549 	msg->msg_req.hc_connid = VMBUS_CONNID_MESSAGE;
550 	msg->msg_req.hc_msgtype = 1;
551 
552 	if (!(msg->msg_flags & MSGF_NOQUEUE)) {
553 		mtx_enter(&sc->sc_reqlck);
554 		TAILQ_INSERT_TAIL(&sc->sc_reqs, msg, msg_entry);
555 		mtx_leave(&sc->sc_reqlck);
556 	}
557 
558 	for (i = 0; i < nitems(delays); i++) {
559 		status = hv_hypercall(sc, HYPERCALL_POST_MESSAGE,
560 		    &msg->msg_req, NULL);
561 		if (status == HYPERCALL_STATUS_SUCCESS)
562 			break;
563 		if (msg->msg_flags & MSGF_NOSLEEP) {
564 			delay(delays[i]);
565 			s = splnet();
566 			hv_intr();
567 			splx(s);
568 		} else
569 			tsleep(wchan, PRIBIO, wchan, 1);
570 	}
571 	if (status != 0) {
572 		printf("%s: posting vmbus message failed with %d\n",
573 		    sc->sc_dev.dv_xname, status);
574 		if (!(msg->msg_flags & MSGF_NOQUEUE)) {
575 			mtx_enter(&sc->sc_reqlck);
576 			TAILQ_REMOVE(&sc->sc_reqs, msg, msg_entry);
577 			mtx_leave(&sc->sc_reqlck);
578 		}
579 		return (EIO);
580 	}
581 
582 	return (0);
583 }
584 
585 static int
586 hv_reply_done(struct hv_softc *sc, struct hv_msg *msg)
587 {
588 	struct hv_msg *m;
589 
590 	mtx_enter(&sc->sc_rsplck);
591 	TAILQ_FOREACH(m, &sc->sc_rsps, msg_entry) {
592 		if (m == msg) {
593 			mtx_leave(&sc->sc_rsplck);
594 			return (1);
595 		}
596 	}
597 	mtx_leave(&sc->sc_rsplck);
598 	return (0);
599 }
600 
601 int
602 hv_reply(struct hv_softc *sc, struct hv_msg *msg)
603 {
604 	if (msg->msg_flags & MSGF_NOQUEUE)
605 		return (0);
606 
607 	hv_wait(sc, hv_reply_done, msg, msg, "hvreply");
608 
609 	mtx_enter(&sc->sc_rsplck);
610 	TAILQ_REMOVE(&sc->sc_rsps, msg, msg_entry);
611 	mtx_leave(&sc->sc_rsplck);
612 
613 	return (0);
614 }
615 
616 void
617 hv_wait(struct hv_softc *sc, int (*cond)(struct hv_softc *, struct hv_msg *),
618     struct hv_msg *msg, void *wchan, const char *wmsg)
619 {
620 	int s;
621 
622 	KASSERT(cold ? msg->msg_flags & MSGF_NOSLEEP : 1);
623 
624 	while (!cond(sc, msg)) {
625 		if (msg->msg_flags & MSGF_NOSLEEP) {
626 			delay(1000);
627 			s = splnet();
628 			hv_intr();
629 			splx(s);
630 		} else
631 			tsleep(wchan, PRIBIO, wmsg ? wmsg : "hvwait", 1);
632 	}
633 }
634 
635 uint16_t
636 hv_intr_signal(struct hv_softc *sc, void *con)
637 {
638 	uint64_t status;
639 
640 	status = hv_hypercall(sc, HYPERCALL_SIGNAL_EVENT, con, NULL);
641 	return ((uint16_t)status);
642 }
643 
644 void
645 hv_intr(void)
646 {
647 	struct hv_softc *sc = hv_sc;
648 
649 	hv_event_intr(sc);
650 	hv_message_intr(sc);
651 }
652 
653 void
654 hv_event_intr(struct hv_softc *sc)
655 {
656 	struct vmbus_evtflags *evt;
657 	struct cpu_info *ci = curcpu();
658 	int cpu = CPU_INFO_UNIT(ci);
659 	int bit, row, maxrow, chanid;
660 	struct hv_channel *ch;
661 	u_long *revents, pending;
662 
663 	evt = (struct vmbus_evtflags *)sc->sc_siep[cpu] +
664 	    VMBUS_SINT_MESSAGE;
665 	if ((sc->sc_proto == VMBUS_VERSION_WS2008) ||
666 	    (sc->sc_proto == VMBUS_VERSION_WIN7)) {
667 		if (!test_bit(0, &evt->evt_flags[0]))
668 			return;
669 		clear_bit(0, &evt->evt_flags[0]);
670 		maxrow = VMBUS_CHAN_MAX_COMPAT / VMBUS_EVTFLAG_LEN;
671 		/*
672 		 * receive size is 1/2 page and divide that by 4 bytes
673 		 */
674 		revents = sc->sc_revents;
675 	} else {
676 		maxrow = nitems(evt->evt_flags);
677 		/*
678 		 * On Host with Win8 or above, the event page can be
679 		 * checked directly to get the id of the channel
680 		 * that has the pending interrupt.
681 		 */
682 		revents = &evt->evt_flags[0];
683 	}
684 
685 	for (row = 0; row < maxrow; row++) {
686 		if (revents[row] == 0)
687 			continue;
688 		pending = atomic_swap_ulong(&revents[row], 0);
689 		for (bit = 0; pending > 0; pending >>= 1, bit++) {
690 			if ((pending & 1) == 0)
691 				continue;
692 			chanid = (row * LONG_BIT) + bit;
693 			/* vmbus channel protocol message */
694 			if (chanid == 0)
695 				continue;
696 			ch = hv_channel_lookup(sc, chanid);
697 			if (ch == NULL) {
698 				printf("%s: unhandled event on %d\n",
699 				    sc->sc_dev.dv_xname, chanid);
700 				continue;
701 			}
702 			if (ch->ch_state != HV_CHANSTATE_OPENED) {
703 				printf("%s: channel %d is not active\n",
704 				    sc->sc_dev.dv_xname, chanid);
705 				continue;
706 			}
707 			ch->ch_evcnt.ec_count++;
708 			if (ch->ch_handler)
709 				ch->ch_handler(ch->ch_ctx);
710 		}
711 	}
712 }
713 
714 void
715 hv_message_intr(struct hv_softc *sc)
716 {
717 	struct vmbus_message *msg;
718 	struct vmbus_chanmsg_hdr *hdr;
719 	struct cpu_info *ci = curcpu();
720 	int cpu = CPU_INFO_UNIT(ci);
721 
722 	for (;;) {
723 		msg = (struct vmbus_message *)sc->sc_simp[cpu] +
724 		    VMBUS_SINT_MESSAGE;
725 		if (msg->msg_type == VMBUS_MSGTYPE_NONE)
726 			break;
727 
728 		hdr = (struct vmbus_chanmsg_hdr *)msg->msg_data;
729 		if (hdr->chm_type >= VMBUS_CHANMSG_COUNT) {
730 			printf("%s: unhandled message type %u flags %#x\n",
731 			    sc->sc_dev.dv_xname, hdr->chm_type,
732 			    msg->msg_flags);
733 			goto skip;
734 		}
735 		if (hv_msg_dispatch[hdr->chm_type].hmd_handler)
736 			hv_msg_dispatch[hdr->chm_type].hmd_handler(sc, hdr);
737 		else
738 			printf("%s: unhandled message type %u\n",
739 			    sc->sc_dev.dv_xname, hdr->chm_type);
740  skip:
741 		msg->msg_type = VMBUS_MSGTYPE_NONE;
742 		membar_sync();
743 		if (msg->msg_flags & VMBUS_MSGFLAG_PENDING)
744 			wrmsr(MSR_HV_EOM, 0);
745 	}
746 }
747 
748 void
749 hv_channel_response(struct hv_softc *sc, struct vmbus_chanmsg_hdr *rsphdr)
750 {
751 	struct hv_msg *msg;
752 	struct vmbus_chanmsg_hdr *reqhdr;
753 	int req;
754 
755 	req = hv_msg_dispatch[rsphdr->chm_type].hmd_request;
756 	mtx_enter(&sc->sc_reqlck);
757 	TAILQ_FOREACH(msg, &sc->sc_reqs, msg_entry) {
758 		reqhdr = (struct vmbus_chanmsg_hdr *)&msg->msg_req.hc_data;
759 		if (reqhdr->chm_type == req) {
760 			TAILQ_REMOVE(&sc->sc_reqs, msg, msg_entry);
761 			break;
762 		}
763 	}
764 	mtx_leave(&sc->sc_reqlck);
765 	if (msg != NULL) {
766 		memcpy(msg->msg_rsp, rsphdr, msg->msg_rsplen);
767 		mtx_enter(&sc->sc_rsplck);
768 		TAILQ_INSERT_TAIL(&sc->sc_rsps, msg, msg_entry);
769 		mtx_leave(&sc->sc_rsplck);
770 		wakeup(msg);
771 	}
772 }
773 
774 void
775 hv_channel_offer(struct hv_softc *sc, struct vmbus_chanmsg_hdr *hdr)
776 {
777 	struct hv_offer *co;
778 
779 	co = malloc(sizeof(*co), M_DEVBUF, M_NOWAIT | M_ZERO);
780 	if (co == NULL) {
781 		printf("%s: failed to allocate an offer object\n",
782 		    sc->sc_dev.dv_xname);
783 		return;
784 	}
785 
786 	memcpy(&co->co_chan, hdr, sizeof(co->co_chan));
787 
788 	mtx_enter(&sc->sc_offerlck);
789 	SIMPLEQ_INSERT_TAIL(&sc->sc_offers, co, co_entry);
790 	mtx_leave(&sc->sc_offerlck);
791 }
792 
793 void
794 hv_channel_delivered(struct hv_softc *sc, struct vmbus_chanmsg_hdr *hdr)
795 {
796 	atomic_setbits_int(&sc->sc_flags, HSF_OFFERS_DELIVERED);
797 	wakeup(&sc->sc_offers);
798 }
799 
800 int
801 hv_vmbus_connect(struct hv_softc *sc)
802 {
803 	const uint32_t versions[] = {
804 		VMBUS_VERSION_WIN8_1, VMBUS_VERSION_WIN8,
805 		VMBUS_VERSION_WIN7, VMBUS_VERSION_WS2008
806 	};
807 	struct vmbus_chanmsg_connect cmd;
808 	struct vmbus_chanmsg_connect_resp rsp;
809 	paddr_t epa, mpa1, mpa2;
810 	int i;
811 
812 	sc->sc_events = km_alloc(PAGE_SIZE, &kv_any, &kp_zero, &kd_nowait);
813 	if (sc->sc_events == NULL) {
814 		printf(": failed to allocate channel port events page\n");
815 		goto errout;
816 	}
817 	if (!pmap_extract(pmap_kernel(), (vaddr_t)sc->sc_events, &epa)) {
818 		printf(": channel port events page PA extraction failed\n");
819 		goto errout;
820 	}
821 
822 	sc->sc_wevents = (u_long *)sc->sc_events;
823 	sc->sc_revents = (u_long *)((caddr_t)sc->sc_events + (PAGE_SIZE >> 1));
824 
825 	sc->sc_monitor[0] = km_alloc(PAGE_SIZE, &kv_any, &kp_zero, &kd_nowait);
826 	if (sc->sc_monitor[0] == NULL) {
827 		printf(": failed to allocate monitor page 1\n");
828 		goto errout;
829 	}
830 	if (!pmap_extract(pmap_kernel(), (vaddr_t)sc->sc_monitor[0], &mpa1)) {
831 		printf(": monitor page 1 PA extraction failed\n");
832 		goto errout;
833 	}
834 
835 	sc->sc_monitor[1] = km_alloc(PAGE_SIZE, &kv_any, &kp_zero, &kd_nowait);
836 	if (sc->sc_monitor[1] == NULL) {
837 		printf(": failed to allocate monitor page 2\n");
838 		goto errout;
839 	}
840 	if (!pmap_extract(pmap_kernel(), (vaddr_t)sc->sc_monitor[1], &mpa2)) {
841 		printf(": monitor page 2 PA extraction failed\n");
842 		goto errout;
843 	}
844 
845 	memset(&cmd, 0, sizeof(cmd));
846 	cmd.chm_hdr.chm_type = VMBUS_CHANMSG_CONNECT;
847 	cmd.chm_evtflags = (uint64_t)epa;
848 	cmd.chm_mnf1 = (uint64_t)mpa1;
849 	cmd.chm_mnf2 = (uint64_t)mpa2;
850 
851 	memset(&rsp, 0, sizeof(rsp));
852 
853 	for (i = 0; i < nitems(versions); i++) {
854 		cmd.chm_ver = versions[i];
855 		if (hv_cmd(sc, &cmd, sizeof(cmd), &rsp, sizeof(rsp),
856 		    HCF_NOSLEEP)) {
857 			DPRINTF("%s: CONNECT failed\n",
858 			    sc->sc_dev.dv_xname);
859 			goto errout;
860 		}
861 		if (rsp.chm_done) {
862 			sc->sc_flags |= HSF_CONNECTED;
863 			sc->sc_proto = versions[i];
864 			sc->sc_handle = VMBUS_GPADL_START;
865 			break;
866 		}
867 	}
868 	if (i == nitems(versions)) {
869 		printf("%s: failed to negotiate protocol version\n",
870 		    sc->sc_dev.dv_xname);
871 		goto errout;
872 	}
873 
874 	return (0);
875 
876  errout:
877 	if (sc->sc_events) {
878 		km_free(sc->sc_events, PAGE_SIZE, &kv_any, &kp_zero);
879 		sc->sc_events = NULL;
880 		sc->sc_wevents = NULL;
881 		sc->sc_revents = NULL;
882 	}
883 	if (sc->sc_monitor[0]) {
884 		km_free(sc->sc_monitor[0], PAGE_SIZE, &kv_any, &kp_zero);
885 		sc->sc_monitor[0] = NULL;
886 	}
887 	if (sc->sc_monitor[1]) {
888 		km_free(sc->sc_monitor[1], PAGE_SIZE, &kv_any, &kp_zero);
889 		sc->sc_monitor[1] = NULL;
890 	}
891 	return (-1);
892 }
893 
894 #ifdef HYPERV_DEBUG
895 static inline char *
896 guidprint(struct hv_guid *a)
897 {
898 	/* 3     0  5  4 7 6  8 9  10        15 */
899 	/* 33221100-5544-7766-9988-FFEEDDCCBBAA */
900 	static char buf[16 * 2 + 4 + 1];
901 	int i, j = 0;
902 
903 	for (i = 3; i != -1; i -= 1, j += 2)
904 		snprintf(&buf[j], 3, "%02x", (uint8_t)a->data[i]);
905 	buf[j++] = '-';
906 	for (i = 5; i != 3; i -= 1, j += 2)
907 		snprintf(&buf[j], 3, "%02x", (uint8_t)a->data[i]);
908 	buf[j++] = '-';
909 	for (i = 7; i != 5; i -= 1, j += 2)
910 		snprintf(&buf[j], 3, "%02x", (uint8_t)a->data[i]);
911 	buf[j++] = '-';
912 	for (i = 8; i < 10; i += 1, j += 2)
913 		snprintf(&buf[j], 3, "%02x", (uint8_t)a->data[i]);
914 	buf[j++] = '-';
915 	for (i = 10; i < 16; i += 1, j += 2)
916 		snprintf(&buf[j], 3, "%02x", (uint8_t)a->data[i]);
917 	return (&buf[0]);
918 }
919 #endif	/* HYPERV_DEBUG */
920 
921 void
922 hv_guid_sprint(struct hv_guid *guid, char *str, size_t size)
923 {
924 	const struct {
925 		const struct hv_guid	*guid;
926 		const char		*ident;
927 	} map[] = {
928 		{ &hv_guid_network,	"network" },
929 		{ &hv_guid_ide,		"ide" },
930 		{ &hv_guid_scsi,	"scsi" },
931 		{ &hv_guid_shutdown,	"shutdown" },
932 		{ &hv_guid_timesync,	"timesync" },
933 		{ &hv_guid_heartbeat,	"heartbeat" },
934 		{ &hv_guid_kvp,		"kvp" },
935 #ifdef HYPERV_DEBUG
936 		{ &hv_guid_vss,		"vss" },
937 		{ &hv_guid_dynmem,	"dynamic-memory" },
938 		{ &hv_guid_mouse,	"mouse" },
939 		{ &hv_guid_kbd,		"keyboard" },
940 		{ &hv_guid_video,	"video" },
941 		{ &hv_guid_fc,		"fiber-channel" },
942 		{ &hv_guid_fcopy,	"file-copy" },
943 		{ &hv_guid_pcie,	"pcie-passthrough" },
944 		{ &hv_guid_netdir,	"network-direct" },
945 		{ &hv_guid_rdesktop,	"remote-desktop" },
946 		{ &hv_guid_avma1,	"avma-1" },
947 		{ &hv_guid_avma2,	"avma-2" },
948 		{ &hv_guid_avma3,	"avma-3" },
949 		{ &hv_guid_avma4,	"avma-4" },
950 #endif
951 	};
952 	int i;
953 
954 	for (i = 0; i < nitems(map); i++) {
955 		if (memcmp(guid, map[i].guid, sizeof(*guid)) == 0) {
956 			strlcpy(str, map[i].ident, size);
957 			return;
958 		}
959 	}
960 #ifdef HYPERV_DEBUG
961 	strlcpy(str, guidprint(guid), size);
962 #endif
963 }
964 
965 static int
966 hv_channel_scan_done(struct hv_softc *sc, struct hv_msg *msg __unused)
967 {
968 	return (sc->sc_flags & HSF_OFFERS_DELIVERED);
969 }
970 
971 int
972 hv_channel_scan(struct hv_softc *sc)
973 {
974 	struct vmbus_chanmsg_hdr hdr;
975 	struct vmbus_chanmsg_choffer rsp;
976 	struct hv_offer *co;
977 
978 	SIMPLEQ_INIT(&sc->sc_offers);
979 	mtx_init(&sc->sc_offerlck, IPL_NET);
980 
981 	memset(&hdr, 0, sizeof(hdr));
982 	hdr.chm_type = VMBUS_CHANMSG_CHREQUEST;
983 
984 	if (hv_cmd(sc, &hdr, sizeof(hdr), &rsp, sizeof(rsp),
985 	    HCF_NOSLEEP | HCF_NOREPLY)) {
986 		DPRINTF("%s: CHREQUEST failed\n", sc->sc_dev.dv_xname);
987 		return (-1);
988 	}
989 
990 	hv_wait(sc, hv_channel_scan_done, (struct hv_msg *)&hdr,
991 	    &sc->sc_offers, "hvscan");
992 
993 	TAILQ_INIT(&sc->sc_channels);
994 	mtx_init(&sc->sc_channelck, IPL_NET);
995 
996 	mtx_enter(&sc->sc_offerlck);
997 	while (!SIMPLEQ_EMPTY(&sc->sc_offers)) {
998 		co = SIMPLEQ_FIRST(&sc->sc_offers);
999 		SIMPLEQ_REMOVE_HEAD(&sc->sc_offers, co_entry);
1000 		mtx_leave(&sc->sc_offerlck);
1001 
1002 		hv_process_offer(sc, co);
1003 		free(co, M_DEVBUF, sizeof(*co));
1004 
1005 		mtx_enter(&sc->sc_offerlck);
1006 	}
1007 	mtx_leave(&sc->sc_offerlck);
1008 
1009 	return (0);
1010 }
1011 
1012 void
1013 hv_process_offer(struct hv_softc *sc, struct hv_offer *co)
1014 {
1015 	struct hv_channel *ch, *nch;
1016 
1017 	nch = malloc(sizeof(*nch), M_DEVBUF, M_ZERO | M_NOWAIT);
1018 	if (nch == NULL) {
1019 		printf("%s: failed to allocate memory for the channel\n",
1020 		    sc->sc_dev.dv_xname);
1021 		return;
1022 	}
1023 	nch->ch_sc = sc;
1024 	hv_guid_sprint(&co->co_chan.chm_chtype, nch->ch_ident,
1025 	    sizeof(nch->ch_ident));
1026 
1027 	/*
1028 	 * By default we setup state to enable batched reading.
1029 	 * A specific service can choose to disable this prior
1030 	 * to opening the channel.
1031 	 */
1032 	nch->ch_flags |= CHF_BATCHED;
1033 
1034 	KASSERT((((vaddr_t)&nch->ch_monprm) & 0x7) == 0);
1035 	memset(&nch->ch_monprm, 0, sizeof(nch->ch_monprm));
1036 	nch->ch_monprm.mp_connid = VMBUS_CONNID_EVENT;
1037 
1038 	if (sc->sc_proto != VMBUS_VERSION_WS2008)
1039 		nch->ch_monprm.mp_connid = co->co_chan.chm_connid;
1040 
1041 	if (co->co_chan.chm_flags1 & VMBUS_CHOFFER_FLAG1_HASMNF) {
1042 		nch->ch_mgroup = co->co_chan.chm_montrig / VMBUS_MONTRIG_LEN;
1043 		nch->ch_mindex = co->co_chan.chm_montrig % VMBUS_MONTRIG_LEN;
1044 		nch->ch_flags |= CHF_MONITOR;
1045 	}
1046 
1047 	nch->ch_id = co->co_chan.chm_chanid;
1048 
1049 	memcpy(&nch->ch_type, &co->co_chan.chm_chtype, sizeof(ch->ch_type));
1050 	memcpy(&nch->ch_inst, &co->co_chan.chm_chinst, sizeof(ch->ch_inst));
1051 
1052 	mtx_enter(&sc->sc_channelck);
1053 	TAILQ_FOREACH(ch, &sc->sc_channels, ch_entry) {
1054 		if (!memcmp(&ch->ch_type, &nch->ch_type, sizeof(ch->ch_type)) &&
1055 		    !memcmp(&ch->ch_inst, &nch->ch_inst, sizeof(ch->ch_inst)))
1056 			break;
1057 	}
1058 	if (ch != NULL) {
1059 		if (co->co_chan.chm_subidx == 0) {
1060 			printf("%s: unknown offer \"%s\"\n",
1061 			    sc->sc_dev.dv_xname, nch->ch_ident);
1062 			mtx_leave(&sc->sc_channelck);
1063 			free(nch, M_DEVBUF, sizeof(*nch));
1064 			return;
1065 		}
1066 #ifdef HYPERV_DEBUG
1067 		printf("%s: subchannel %u for \"%s\"\n", sc->sc_dev.dv_xname,
1068 		    co->co_chan.chm_subidx, ch->ch_ident);
1069 #endif
1070 		mtx_leave(&sc->sc_channelck);
1071 		free(nch, M_DEVBUF, sizeof(*nch));
1072 		return;
1073 	}
1074 
1075 	nch->ch_state = HV_CHANSTATE_OFFERED;
1076 
1077 	TAILQ_INSERT_TAIL(&sc->sc_channels, nch, ch_entry);
1078 	mtx_leave(&sc->sc_channelck);
1079 
1080 #ifdef HYPERV_DEBUG
1081 	printf("%s: channel %u: \"%s\"", sc->sc_dev.dv_xname, nch->ch_id,
1082 	    nch->ch_ident);
1083 	if (nch->ch_flags & CHF_MONITOR)
1084 		printf(", monitor %u\n", co->co_chan.chm_montrig);
1085 	else
1086 		printf("\n");
1087 #endif
1088 }
1089 
1090 struct hv_channel *
1091 hv_channel_lookup(struct hv_softc *sc, uint32_t relid)
1092 {
1093 	struct hv_channel *ch;
1094 
1095 	TAILQ_FOREACH(ch, &sc->sc_channels, ch_entry) {
1096 		if (ch->ch_id == relid)
1097 			return (ch);
1098 	}
1099 	return (NULL);
1100 }
1101 
1102 int
1103 hv_channel_ring_create(struct hv_channel *ch, uint32_t buflen)
1104 {
1105 	struct hv_softc *sc = ch->ch_sc;
1106 
1107 	buflen = roundup(buflen, PAGE_SIZE) + sizeof(struct vmbus_bufring);
1108 	ch->ch_ring = km_alloc(2 * buflen, &kv_any, &kp_zero, cold ?
1109 	    &kd_nowait : &kd_waitok);
1110 	if (ch->ch_ring == NULL) {
1111 		printf("%s: failed to allocate channel ring\n",
1112 		    sc->sc_dev.dv_xname);
1113 		return (-1);
1114 	}
1115 	ch->ch_ring_size = 2 * buflen;
1116 
1117 	memset(&ch->ch_wrd, 0, sizeof(ch->ch_wrd));
1118 	ch->ch_wrd.rd_ring = (struct vmbus_bufring *)ch->ch_ring;
1119 	ch->ch_wrd.rd_size = buflen;
1120 	ch->ch_wrd.rd_dsize = buflen - sizeof(struct vmbus_bufring);
1121 	mtx_init(&ch->ch_wrd.rd_lock, IPL_NET);
1122 
1123 	memset(&ch->ch_rrd, 0, sizeof(ch->ch_rrd));
1124 	ch->ch_rrd.rd_ring = (struct vmbus_bufring *)((uint8_t *)ch->ch_ring +
1125 	    buflen);
1126 	ch->ch_rrd.rd_size = buflen;
1127 	ch->ch_rrd.rd_dsize = buflen - sizeof(struct vmbus_bufring);
1128 	mtx_init(&ch->ch_rrd.rd_lock, IPL_NET);
1129 
1130 	if (hv_handle_alloc(ch, ch->ch_ring, 2 * buflen, &ch->ch_ring_gpadl)) {
1131 		printf("%s: failed to obtain a PA handle for the ring\n",
1132 		    sc->sc_dev.dv_xname);
1133 		hv_channel_ring_destroy(ch);
1134 		return (-1);
1135 	}
1136 
1137 	return (0);
1138 }
1139 
1140 void
1141 hv_channel_ring_destroy(struct hv_channel *ch)
1142 {
1143 	km_free(ch->ch_ring, ch->ch_ring_size, &kv_any, &kp_zero);
1144 	ch->ch_ring = NULL;
1145 	hv_handle_free(ch, ch->ch_ring_gpadl);
1146 
1147 	memset(&ch->ch_wrd, 0, sizeof(ch->ch_wrd));
1148 	memset(&ch->ch_rrd, 0, sizeof(ch->ch_rrd));
1149 }
1150 
1151 int
1152 hv_channel_open(struct hv_channel *ch, size_t buflen, void *udata,
1153     size_t udatalen, void (*handler)(void *), void *arg)
1154 {
1155 	struct hv_softc *sc = ch->ch_sc;
1156 	struct vmbus_chanmsg_chopen cmd;
1157 	struct vmbus_chanmsg_chopen_resp rsp;
1158 	int rv;
1159 
1160 	if (ch->ch_ring == NULL &&
1161 	    hv_channel_ring_create(ch, buflen)) {
1162 		DPRINTF("%s: failed to create channel ring\n",
1163 		    sc->sc_dev.dv_xname);
1164 		return (-1);
1165 	}
1166 
1167 	memset(&cmd, 0, sizeof(cmd));
1168 	cmd.chm_hdr.chm_type = VMBUS_CHANMSG_CHOPEN;
1169 	cmd.chm_openid = ch->ch_id;
1170 	cmd.chm_chanid = ch->ch_id;
1171 	cmd.chm_gpadl = ch->ch_ring_gpadl;
1172 	cmd.chm_txbr_pgcnt = ch->ch_wrd.rd_size >> PAGE_SHIFT;
1173 	cmd.chm_vcpuid = ch->ch_vcpu;
1174 
1175 	if (udata && udatalen > 0)
1176 		memcpy(cmd.chm_udata, udata, udatalen);
1177 
1178 	memset(&rsp, 0, sizeof(rsp));
1179 
1180 	ch->ch_handler = handler;
1181 	ch->ch_ctx = arg;
1182 
1183 	ch->ch_state = HV_CHANSTATE_OPENED;
1184 
1185 	rv = hv_cmd(sc, &cmd, sizeof(cmd), &rsp, sizeof(rsp),
1186 	    cold ? HCF_NOSLEEP : HCF_SLEEPOK);
1187 	if (rv) {
1188 		hv_channel_ring_destroy(ch);
1189 		DPRINTF("%s: CHOPEN failed with %d\n",
1190 		    sc->sc_dev.dv_xname, rv);
1191 		ch->ch_handler = NULL;
1192 		ch->ch_ctx = NULL;
1193 		ch->ch_state = HV_CHANSTATE_OFFERED;
1194 		return (-1);
1195 	}
1196 
1197 	return (0);
1198 }
1199 
1200 int
1201 hv_channel_close(struct hv_channel *ch)
1202 {
1203 	struct hv_softc *sc = ch->ch_sc;
1204 	struct vmbus_chanmsg_chclose cmd;
1205 	int rv;
1206 
1207 	memset(&cmd, 0, sizeof(cmd));
1208 	cmd.chm_hdr.chm_type = VMBUS_CHANMSG_CHCLOSE;
1209 	cmd.chm_chanid = ch->ch_id;
1210 
1211 	ch->ch_state = HV_CHANSTATE_CLOSING;
1212 	rv = hv_cmd(sc, &cmd, sizeof(cmd), NULL, 0, HCF_NOREPLY);
1213 	if (rv) {
1214 		DPRINTF("%s: CHCLOSE failed with %d\n",
1215 		    sc->sc_dev.dv_xname, rv);
1216 		return (-1);
1217 	}
1218 	ch->ch_state = HV_CHANSTATE_CLOSED;
1219 	hv_channel_ring_destroy(ch);
1220 	return (0);
1221 }
1222 
1223 static inline void
1224 hv_channel_setevent(struct hv_softc *sc, struct hv_channel *ch)
1225 {
1226 	struct vmbus_mon_trig *mtg;
1227 
1228 	/* Each uint32_t represents 32 channels */
1229 	set_bit(ch->ch_id, sc->sc_wevents);
1230 	if (ch->ch_flags & CHF_MONITOR) {
1231 		mtg = &sc->sc_monitor[1]->mnf_trigs[ch->ch_mgroup];
1232 		set_bit(ch->ch_mindex, &mtg->mt_pending);
1233 	} else
1234 		hv_intr_signal(sc, &ch->ch_monprm);
1235 }
1236 
1237 static inline void
1238 hv_ring_put(struct hv_ring_data *wrd, uint8_t *data, uint32_t datalen)
1239 {
1240 	int left = MIN(datalen, wrd->rd_dsize - wrd->rd_prod);
1241 
1242 	memcpy(&wrd->rd_ring->br_data[wrd->rd_prod], data, left);
1243 	memcpy(&wrd->rd_ring->br_data[0], data + left, datalen - left);
1244 	wrd->rd_prod += datalen;
1245 	if (wrd->rd_prod >= wrd->rd_dsize)
1246 		wrd->rd_prod -= wrd->rd_dsize;
1247 }
1248 
1249 static inline void
1250 hv_ring_get(struct hv_ring_data *rrd, uint8_t *data, uint32_t datalen,
1251     int peek)
1252 {
1253 	int left = MIN(datalen, rrd->rd_dsize - rrd->rd_cons);
1254 
1255 	memcpy(data, &rrd->rd_ring->br_data[rrd->rd_cons], left);
1256 	memcpy(data + left, &rrd->rd_ring->br_data[0], datalen - left);
1257 	if (!peek) {
1258 		rrd->rd_cons += datalen;
1259 		if (rrd->rd_cons >= rrd->rd_dsize)
1260 			rrd->rd_cons -= rrd->rd_dsize;
1261 	}
1262 }
1263 
1264 static inline void
1265 hv_ring_avail(struct hv_ring_data *rd, uint32_t *towrite, uint32_t *toread)
1266 {
1267 	uint32_t ridx = rd->rd_ring->br_rindex;
1268 	uint32_t widx = rd->rd_ring->br_windex;
1269 	uint32_t r, w;
1270 
1271 	if (widx >= ridx)
1272 		w = rd->rd_dsize - (widx - ridx);
1273 	else
1274 		w = ridx - widx;
1275 	r = rd->rd_dsize - w;
1276 	if (towrite)
1277 		*towrite = w;
1278 	if (toread)
1279 		*toread = r;
1280 }
1281 
1282 int
1283 hv_ring_write(struct hv_ring_data *wrd, struct iovec *iov, int iov_cnt,
1284     int *needsig)
1285 {
1286 	uint64_t indices = 0;
1287 	uint32_t avail, oprod, datalen = sizeof(indices);
1288 	int i;
1289 
1290 	for (i = 0; i < iov_cnt; i++)
1291 		datalen += iov[i].iov_len;
1292 
1293 	KASSERT(datalen <= wrd->rd_dsize);
1294 
1295 	hv_ring_avail(wrd, &avail, NULL);
1296 	if (avail <= datalen) {
1297 		DPRINTF("%s: avail %u datalen %u\n", __func__, avail, datalen);
1298 		return (EAGAIN);
1299 	}
1300 
1301 	oprod = wrd->rd_prod;
1302 
1303 	for (i = 0; i < iov_cnt; i++)
1304 		hv_ring_put(wrd, iov[i].iov_base, iov[i].iov_len);
1305 
1306 	indices = (uint64_t)oprod << 32;
1307 	hv_ring_put(wrd, (uint8_t *)&indices, sizeof(indices));
1308 
1309 	membar_sync();
1310 	wrd->rd_ring->br_windex = wrd->rd_prod;
1311 	membar_sync();
1312 
1313 	/* Signal when the ring transitions from being empty to non-empty */
1314 	if (wrd->rd_ring->br_imask == 0 &&
1315 	    wrd->rd_ring->br_rindex == oprod)
1316 		*needsig = 1;
1317 	else
1318 		*needsig = 0;
1319 
1320 	return (0);
1321 }
1322 
1323 int
1324 hv_channel_send(struct hv_channel *ch, void *data, uint32_t datalen,
1325     uint64_t rid, int type, uint32_t flags)
1326 {
1327 	struct hv_softc *sc = ch->ch_sc;
1328 	struct vmbus_chanpkt cp;
1329 	struct iovec iov[3];
1330 	uint32_t pktlen, pktlen_aligned;
1331 	uint64_t zeropad = 0;
1332 	int rv, needsig = 0;
1333 
1334 	pktlen = sizeof(cp) + datalen;
1335 	pktlen_aligned = roundup(pktlen, sizeof(uint64_t));
1336 
1337 	cp.cp_hdr.cph_type = type;
1338 	cp.cp_hdr.cph_flags = flags;
1339 	VMBUS_CHANPKT_SETLEN(cp.cp_hdr.cph_hlen, sizeof(cp));
1340 	VMBUS_CHANPKT_SETLEN(cp.cp_hdr.cph_tlen, pktlen_aligned);
1341 	cp.cp_hdr.cph_tid = rid;
1342 
1343 	iov[0].iov_base = &cp;
1344 	iov[0].iov_len = sizeof(cp);
1345 
1346 	iov[1].iov_base = data;
1347 	iov[1].iov_len = datalen;
1348 
1349 	iov[2].iov_base = &zeropad;
1350 	iov[2].iov_len = pktlen_aligned - pktlen;
1351 
1352 	mtx_enter(&ch->ch_wrd.rd_lock);
1353 	rv = hv_ring_write(&ch->ch_wrd, iov, 3, &needsig);
1354 	mtx_leave(&ch->ch_wrd.rd_lock);
1355 	if (rv == 0 && needsig)
1356 		hv_channel_setevent(sc, ch);
1357 
1358 	return (rv);
1359 }
1360 
1361 int
1362 hv_channel_send_sgl(struct hv_channel *ch, struct vmbus_gpa *sgl,
1363     uint32_t nsge, void *data, uint32_t datalen, uint64_t rid)
1364 {
1365 	struct hv_softc *sc = ch->ch_sc;
1366 	struct vmbus_chanpkt_sglist cp;
1367 	struct iovec iov[4];
1368 	uint32_t buflen, pktlen, pktlen_aligned;
1369 	uint64_t zeropad = 0;
1370 	int rv, needsig = 0;
1371 
1372 	buflen = sizeof(struct vmbus_gpa) * nsge;
1373 	pktlen = sizeof(cp) + datalen + buflen;
1374 	pktlen_aligned = roundup(pktlen, sizeof(uint64_t));
1375 
1376 	cp.cp_hdr.cph_type = VMBUS_CHANPKT_TYPE_GPA;
1377 	cp.cp_hdr.cph_flags = VMBUS_CHANPKT_FLAG_RC;
1378 	VMBUS_CHANPKT_SETLEN(cp.cp_hdr.cph_hlen, sizeof(cp) + buflen);
1379 	VMBUS_CHANPKT_SETLEN(cp.cp_hdr.cph_tlen, pktlen_aligned);
1380 	cp.cp_hdr.cph_tid = rid;
1381 	cp.cp_gpa_cnt = nsge;
1382 	cp.cp_rsvd = 0;
1383 
1384 	iov[0].iov_base = &cp;
1385 	iov[0].iov_len = sizeof(cp);
1386 
1387 	iov[1].iov_base = sgl;
1388 	iov[1].iov_len = buflen;
1389 
1390 	iov[2].iov_base = data;
1391 	iov[2].iov_len = datalen;
1392 
1393 	iov[3].iov_base = &zeropad;
1394 	iov[3].iov_len = pktlen_aligned - pktlen;
1395 
1396 	mtx_enter(&ch->ch_wrd.rd_lock);
1397 	rv = hv_ring_write(&ch->ch_wrd, iov, 4, &needsig);
1398 	mtx_leave(&ch->ch_wrd.rd_lock);
1399 	if (rv == 0 && needsig)
1400 		hv_channel_setevent(sc, ch);
1401 
1402 	return (rv);
1403 }
1404 
1405 int
1406 hv_ring_peek(struct hv_ring_data *rrd, void *data, uint32_t datalen)
1407 {
1408 	uint32_t avail;
1409 
1410 	KASSERT(datalen <= rrd->rd_dsize);
1411 
1412 	hv_ring_avail(rrd, NULL, &avail);
1413 	if (avail < datalen)
1414 		return (EAGAIN);
1415 
1416 	hv_ring_get(rrd, (uint8_t *)data, datalen, 1);
1417 	return (0);
1418 }
1419 
1420 int
1421 hv_ring_read(struct hv_ring_data *rrd, void *data, uint32_t datalen,
1422     uint32_t offset)
1423 {
1424 	uint64_t indices;
1425 	uint32_t avail;
1426 
1427 	KASSERT(datalen <= rrd->rd_dsize);
1428 
1429 	hv_ring_avail(rrd, NULL, &avail);
1430 	if (avail < datalen) {
1431 		DPRINTF("%s: avail %u datalen %u\n", __func__, avail, datalen);
1432 		return (EAGAIN);
1433 	}
1434 
1435 	if (offset) {
1436 		rrd->rd_cons += offset;
1437 		if (rrd->rd_cons >= rrd->rd_dsize)
1438 			rrd->rd_cons -= rrd->rd_dsize;
1439 	}
1440 
1441 	hv_ring_get(rrd, (uint8_t *)data, datalen, 0);
1442 	hv_ring_get(rrd, (uint8_t *)&indices, sizeof(indices), 0);
1443 
1444 	membar_sync();
1445 	rrd->rd_ring->br_rindex = rrd->rd_cons;
1446 
1447 	return (0);
1448 }
1449 
1450 int
1451 hv_channel_recv(struct hv_channel *ch, void *data, uint32_t datalen,
1452     uint32_t *rlen, uint64_t *rid, int raw)
1453 {
1454 	struct vmbus_chanpkt_hdr cph;
1455 	uint32_t offset, pktlen;
1456 	int rv;
1457 
1458 	*rlen = 0;
1459 
1460 	mtx_enter(&ch->ch_rrd.rd_lock);
1461 
1462 	if ((rv = hv_ring_peek(&ch->ch_rrd, &cph, sizeof(cph))) != 0) {
1463 		mtx_leave(&ch->ch_rrd.rd_lock);
1464 		return (rv);
1465 	}
1466 
1467 	offset = raw ? 0 : VMBUS_CHANPKT_GETLEN(cph.cph_hlen);
1468 	pktlen = VMBUS_CHANPKT_GETLEN(cph.cph_tlen) - offset;
1469 	if (pktlen > datalen) {
1470 		mtx_leave(&ch->ch_rrd.rd_lock);
1471 		printf("%s: pktlen %u datalen %u\n", __func__, pktlen, datalen);
1472 		return (EINVAL);
1473 	}
1474 
1475 	rv = hv_ring_read(&ch->ch_rrd, data, pktlen, offset);
1476 	if (rv == 0) {
1477 		*rlen = pktlen;
1478 		*rid = cph.cph_tid;
1479 	}
1480 
1481 	mtx_leave(&ch->ch_rrd.rd_lock);
1482 
1483 	return (rv);
1484 }
1485 
1486 /* How many PFNs can be referenced by the header */
1487 #define HV_NPFNHDR	((VMBUS_MSG_DSIZE_MAX -	\
1488 	  sizeof(struct vmbus_chanmsg_gpadl_conn)) / sizeof(uint64_t))
1489 
1490 /* How many PFNs can be referenced by the body */
1491 #define HV_NPFNBODY	((VMBUS_MSG_DSIZE_MAX -	\
1492 	  sizeof(struct vmbus_chanmsg_gpadl_subconn)) / sizeof(uint64_t))
1493 
1494 int
1495 hv_handle_alloc(struct hv_channel *ch, void *buffer, uint32_t buflen,
1496     uint32_t *handle)
1497 {
1498 	struct hv_softc *sc = ch->ch_sc;
1499 	struct vmbus_chanmsg_gpadl_conn *hdr;
1500 	struct vmbus_chanmsg_gpadl_subconn *cmd;
1501 	struct vmbus_chanmsg_gpadl_connresp rsp;
1502 	struct hv_msg *msg;
1503 	int i, j, last, left, rv;
1504 	int bodylen = 0, ncmds = 0, pfn = 0;
1505 	int waitflag = cold ? M_NOWAIT : M_WAITOK;
1506 	uint64_t *frames;
1507 	paddr_t pa;
1508 	caddr_t body;
1509 	/* Total number of pages to reference */
1510 	int total = atop(buflen);
1511 	/* Number of pages that will fit the header */
1512 	int inhdr = MIN(total, HV_NPFNHDR);
1513 
1514 	KASSERT((buflen & (PAGE_SIZE - 1)) == 0);
1515 
1516 	if ((msg = malloc(sizeof(*msg), M_DEVBUF, M_ZERO | waitflag)) == NULL)
1517 		return (ENOMEM);
1518 
1519 	/* Prepare array of frame addresses */
1520 	if ((frames = mallocarray(total, sizeof(*frames), M_DEVBUF, M_ZERO |
1521 	    waitflag)) == NULL) {
1522 		free(msg, M_DEVBUF, sizeof(*msg));
1523 		return (ENOMEM);
1524 	}
1525 	for (i = 0; i < total; i++) {
1526 		if (!pmap_extract(pmap_kernel(), (vaddr_t)buffer +
1527 		    PAGE_SIZE * i, &pa)) {
1528 			free(msg, M_DEVBUF, sizeof(*msg));
1529 			free(frames, M_DEVBUF, total * sizeof(*frames));
1530 			return (EFAULT);
1531 		}
1532 		frames[i] = atop(pa);
1533 	}
1534 
1535 	msg->msg_req.hc_dsize = sizeof(struct vmbus_chanmsg_gpadl_conn) +
1536 	    inhdr * sizeof(uint64_t);
1537 	hdr = (struct vmbus_chanmsg_gpadl_conn *)msg->msg_req.hc_data;
1538 	msg->msg_rsp = &rsp;
1539 	msg->msg_rsplen = sizeof(rsp);
1540 	if (waitflag == M_NOWAIT)
1541 		msg->msg_flags = MSGF_NOSLEEP;
1542 
1543 	left = total - inhdr;
1544 
1545 	/* Allocate additional gpadl_body structures if required */
1546 	if (left > 0) {
1547 		ncmds = MAX(1, left / HV_NPFNBODY + left % HV_NPFNBODY);
1548 		bodylen = ncmds * VMBUS_MSG_DSIZE_MAX;
1549 		body = malloc(bodylen, M_DEVBUF, M_ZERO | waitflag);
1550 		if (body == NULL) {
1551 			free(msg, M_DEVBUF, sizeof(*msg));
1552 			free(frames, M_DEVBUF, atop(buflen) * sizeof(*frames));
1553 			return (ENOMEM);
1554 		}
1555 	}
1556 
1557 	*handle = atomic_inc_int_nv(&sc->sc_handle);
1558 
1559 	hdr->chm_hdr.chm_type = VMBUS_CHANMSG_GPADL_CONN;
1560 	hdr->chm_chanid = ch->ch_id;
1561 	hdr->chm_gpadl = *handle;
1562 
1563 	/* Single range for a contiguous buffer */
1564 	hdr->chm_range_cnt = 1;
1565 	hdr->chm_range_len = sizeof(struct vmbus_gpa_range) + total *
1566 	    sizeof(uint64_t);
1567 	hdr->chm_range.gpa_ofs = 0;
1568 	hdr->chm_range.gpa_len = buflen;
1569 
1570 	/* Fit as many pages as possible into the header */
1571 	for (i = 0; i < inhdr; i++)
1572 		hdr->chm_range.gpa_page[i] = frames[pfn++];
1573 
1574 	for (i = 0; i < ncmds; i++) {
1575 		cmd = (struct vmbus_chanmsg_gpadl_subconn *)(body +
1576 		    VMBUS_MSG_DSIZE_MAX * i);
1577 		cmd->chm_hdr.chm_type = VMBUS_CHANMSG_GPADL_SUBCONN;
1578 		cmd->chm_gpadl = *handle;
1579 		last = MIN(left, HV_NPFNBODY);
1580 		for (j = 0; j < last; j++)
1581 			cmd->chm_gpa_page[j] = frames[pfn++];
1582 		left -= last;
1583 	}
1584 
1585 	rv = hv_start(sc, msg);
1586 	if (rv != 0) {
1587 		DPRINTF("%s: GPADL_CONN failed\n", sc->sc_dev.dv_xname);
1588 		goto out;
1589 	}
1590 	for (i = 0; i < ncmds; i++) {
1591 		int cmdlen = sizeof(*cmd);
1592 		cmd = (struct vmbus_chanmsg_gpadl_subconn *)(body +
1593 		    VMBUS_MSG_DSIZE_MAX * i);
1594 		/* Last element can be short */
1595 		if (i == ncmds - 1)
1596 			cmdlen += last * sizeof(uint64_t);
1597 		else
1598 			cmdlen += HV_NPFNBODY * sizeof(uint64_t);
1599 		rv = hv_cmd(sc, cmd, cmdlen, NULL, 0, waitflag | HCF_NOREPLY);
1600 		if (rv != 0) {
1601 			DPRINTF("%s: GPADL_SUBCONN (iteration %d/%d) failed "
1602 			    "with %d\n", sc->sc_dev.dv_xname, i, ncmds, rv);
1603 			goto out;
1604 		}
1605 	}
1606 	rv = hv_reply(sc, msg);
1607 	if (rv != 0)
1608 		DPRINTF("%s: GPADL allocation failed with %d\n",
1609 		    sc->sc_dev.dv_xname, rv);
1610 
1611  out:
1612 	free(msg, M_DEVBUF, sizeof(*msg));
1613 	free(frames, M_DEVBUF, total * sizeof(*frames));
1614 	if (bodylen > 0)
1615 		free(body, M_DEVBUF, bodylen);
1616 	if (rv != 0)
1617 		return (rv);
1618 
1619 	KASSERT(*handle == rsp.chm_gpadl);
1620 
1621 	return (0);
1622 }
1623 
1624 void
1625 hv_handle_free(struct hv_channel *ch, uint32_t handle)
1626 {
1627 	struct hv_softc *sc = ch->ch_sc;
1628 	struct vmbus_chanmsg_gpadl_disconn cmd;
1629 	struct vmbus_chanmsg_gpadl_disconn rsp;
1630 	int rv;
1631 
1632 	memset(&cmd, 0, sizeof(cmd));
1633 	cmd.chm_hdr.chm_type = VMBUS_CHANMSG_GPADL_DISCONN;
1634 	cmd.chm_chanid = ch->ch_id;
1635 	cmd.chm_gpadl = handle;
1636 
1637 	rv = hv_cmd(sc, &cmd, sizeof(cmd), &rsp, sizeof(rsp), 0);
1638 	if (rv)
1639 		DPRINTF("%s: GPADL_DISCONN failed with %d\n",
1640 		    sc->sc_dev.dv_xname, rv);
1641 }
1642 
1643 static int
1644 hv_attach_print(void *aux, const char *name)
1645 {
1646 	struct hv_attach_args *aa = aux;
1647 
1648 	if (name)
1649 		printf("\"%s\" at %s", aa->aa_ident, name);
1650 
1651 	return (UNCONF);
1652 }
1653 
1654 int
1655 hv_attach_devices(struct hv_softc *sc)
1656 {
1657 	struct hv_dev *dv;
1658 	struct hv_channel *ch;
1659 
1660 	SLIST_INIT(&sc->sc_devs);
1661 	mtx_init(&sc->sc_devlck, IPL_NET);
1662 
1663 	TAILQ_FOREACH(ch, &sc->sc_channels, ch_entry) {
1664 		if (ch->ch_state != HV_CHANSTATE_OFFERED)
1665 			continue;
1666 		if (!(ch->ch_flags & CHF_MONITOR))
1667 			continue;
1668 		dv = malloc(sizeof(*dv), M_DEVBUF, M_ZERO | M_NOWAIT);
1669 		if (dv == NULL) {
1670 			printf("%s: failed to allocate device object\n",
1671 			    sc->sc_dev.dv_xname);
1672 			return (-1);
1673 		}
1674 		dv->dv_aa.aa_parent = sc;
1675 		dv->dv_aa.aa_type = &ch->ch_type;
1676 		dv->dv_aa.aa_inst = &ch->ch_inst;
1677 		dv->dv_aa.aa_ident = ch->ch_ident;
1678 		dv->dv_aa.aa_chan = ch;
1679 		dv->dv_aa.aa_dmat = sc->sc_dmat;
1680 		mtx_enter(&sc->sc_devlck);
1681 		SLIST_INSERT_HEAD(&sc->sc_devs, dv, dv_entry);
1682 		mtx_leave(&sc->sc_devlck);
1683 		config_found((struct device *)sc, &dv->dv_aa, hv_attach_print);
1684 	}
1685 	return (0);
1686 }
1687 
1688 void
1689 hv_evcount_attach(struct hv_channel *ch, const char *name)
1690 {
1691 	struct hv_softc *sc = ch->ch_sc;
1692 
1693 	evcount_attach(&ch->ch_evcnt, name, &sc->sc_idtvec);
1694 }
1695