hyperv.c revision 307310 
1/*-
2 * Copyright (c) 2009-2012,2016 Microsoft Corp.
3 * Copyright (c) 2012 NetApp Inc.
4 * Copyright (c) 2012 Citrix Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice unmodified, this list of conditions, and the following
12 *    disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/**
30 * Implements low-level interactions with Hypver-V/Azure
31 */
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: stable/11/sys/dev/hyperv/vmbus/hyperv.c 307310 2016-10-14 09:10:41Z sephe $");
34
35#include <sys/param.h>
36#include <sys/kernel.h>
37#include <sys/malloc.h>
38#include <sys/pcpu.h>
39#include <sys/timetc.h>
40#include <machine/bus.h>
41#include <machine/md_var.h>
42#include <vm/vm.h>
43#include <vm/vm_param.h>
44#include <vm/pmap.h>
45
46#include <dev/hyperv/include/hyperv_busdma.h>
47#include <dev/hyperv/vmbus/hv_vmbus_priv.h>
48#include <dev/hyperv/vmbus/hyperv_machdep.h>
49#include <dev/hyperv/vmbus/hyperv_reg.h>
50#include <dev/hyperv/vmbus/hyperv_var.h>
51#include <dev/hyperv/vmbus/vmbus_var.h>
52
53#define HYPERV_FREEBSD_BUILD		0ULL
54#define HYPERV_FREEBSD_VERSION		((uint64_t)__FreeBSD_version)
55#define HYPERV_FREEBSD_OSID		0ULL
56
57#define MSR_HV_GUESTID_BUILD_FREEBSD	\
58	(HYPERV_FREEBSD_BUILD & MSR_HV_GUESTID_BUILD_MASK)
59#define MSR_HV_GUESTID_VERSION_FREEBSD	\
60	((HYPERV_FREEBSD_VERSION << MSR_HV_GUESTID_VERSION_SHIFT) & \
61	 MSR_HV_GUESTID_VERSION_MASK)
62#define MSR_HV_GUESTID_OSID_FREEBSD	\
63	((HYPERV_FREEBSD_OSID << MSR_HV_GUESTID_OSID_SHIFT) & \
64	 MSR_HV_GUESTID_OSID_MASK)
65
66#define MSR_HV_GUESTID_FREEBSD		\
67	(MSR_HV_GUESTID_BUILD_FREEBSD |	\
68	 MSR_HV_GUESTID_VERSION_FREEBSD | \
69	 MSR_HV_GUESTID_OSID_FREEBSD |	\
70	 MSR_HV_GUESTID_OSTYPE_FREEBSD)
71
72struct hypercall_ctx {
73	void			*hc_addr;
74	struct hyperv_dma	hc_dma;
75};
76
77static u_int	hyperv_get_timecount(struct timecounter *tc);
78
79u_int		hyperv_features;
80u_int		hyperv_recommends;
81
82static u_int	hyperv_pm_features;
83static u_int	hyperv_features3;
84
85static struct timecounter	hyperv_timecounter = {
86	.tc_get_timecount	= hyperv_get_timecount,
87	.tc_poll_pps		= NULL,
88	.tc_counter_mask	= 0xffffffff,
89	.tc_frequency		= HYPERV_TIMER_FREQ,
90	.tc_name		= "Hyper-V",
91	.tc_quality		= 2000,
92	.tc_flags		= 0,
93	.tc_priv		= NULL
94};
95
96static struct hypercall_ctx	hypercall_context;
97
98static u_int
99hyperv_get_timecount(struct timecounter *tc __unused)
100{
101	return rdmsr(MSR_HV_TIME_REF_COUNT);
102}
103
104uint64_t
105hypercall_post_message(bus_addr_t msg_paddr)
106{
107	return hypercall_md(hypercall_context.hc_addr,
108	    HYPERCALL_POST_MESSAGE, msg_paddr, 0);
109}
110
111uint64_t
112hypercall_signal_event(bus_addr_t monprm_paddr)
113{
114	return hypercall_md(hypercall_context.hc_addr,
115	    HYPERCALL_SIGNAL_EVENT, monprm_paddr, 0);
116}
117
118int
119hyperv_guid2str(const struct hv_guid *guid, char *buf, size_t sz)
120{
121	const uint8_t *d = guid->data;
122
123	return snprintf(buf, sz, "%02x%02x%02x%02x-"
124	    "%02x%02x-%02x%02x-%02x%02x-"
125	    "%02x%02x%02x%02x%02x%02x",
126	    d[3], d[2], d[1], d[0],
127	    d[5], d[4], d[7], d[6], d[8], d[9],
128	    d[10], d[11], d[12], d[13], d[14], d[15]);
129}
130
131static bool
132hyperv_identify(void)
133{
134	u_int regs[4];
135	unsigned int maxleaf;
136
137	if (vm_guest != VM_GUEST_HV)
138		return (false);
139
140	do_cpuid(CPUID_LEAF_HV_MAXLEAF, regs);
141	maxleaf = regs[0];
142	if (maxleaf < CPUID_LEAF_HV_LIMITS)
143		return (false);
144
145	do_cpuid(CPUID_LEAF_HV_INTERFACE, regs);
146	if (regs[0] != CPUID_HV_IFACE_HYPERV)
147		return (false);
148
149	do_cpuid(CPUID_LEAF_HV_FEATURES, regs);
150	if ((regs[0] & CPUID_HV_MSR_HYPERCALL) == 0) {
151		/*
152		 * Hyper-V w/o Hypercall is impossible; someone
153		 * is faking Hyper-V.
154		 */
155		return (false);
156	}
157	hyperv_features = regs[0];
158	hyperv_pm_features = regs[2];
159	hyperv_features3 = regs[3];
160
161	do_cpuid(CPUID_LEAF_HV_IDENTITY, regs);
162	printf("Hyper-V Version: %d.%d.%d [SP%d]\n",
163	    regs[1] >> 16, regs[1] & 0xffff, regs[0], regs[2]);
164
165	printf("  Features=0x%b\n", hyperv_features,
166	    "\020"
167	    "\001VPRUNTIME"	/* MSR_HV_VP_RUNTIME */
168	    "\002TMREFCNT"	/* MSR_HV_TIME_REF_COUNT */
169	    "\003SYNIC"		/* MSRs for SynIC */
170	    "\004SYNTM"		/* MSRs for SynTimer */
171	    "\005APIC"		/* MSR_HV_{EOI,ICR,TPR} */
172	    "\006HYPERCALL"	/* MSR_HV_{GUEST_OS_ID,HYPERCALL} */
173	    "\007VPINDEX"	/* MSR_HV_VP_INDEX */
174	    "\010RESET"		/* MSR_HV_RESET */
175	    "\011STATS"		/* MSR_HV_STATS_ */
176	    "\012REFTSC"	/* MSR_HV_REFERENCE_TSC */
177	    "\013IDLE"		/* MSR_HV_GUEST_IDLE */
178	    "\014TMFREQ"	/* MSR_HV_{TSC,APIC}_FREQUENCY */
179	    "\015DEBUG");	/* MSR_HV_SYNTH_DEBUG_ */
180	printf("  PM Features=0x%b [C%u]\n",
181	    (hyperv_pm_features & ~CPUPM_HV_CSTATE_MASK),
182	    "\020"
183	    "\005C3HPET",	/* HPET is required for C3 state */
184	    CPUPM_HV_CSTATE(hyperv_pm_features));
185	printf("  Features3=0x%b\n", hyperv_features3,
186	    "\020"
187	    "\001MWAIT"		/* MWAIT */
188	    "\002DEBUG"		/* guest debug support */
189	    "\003PERFMON"	/* performance monitor */
190	    "\004PCPUDPE"	/* physical CPU dynamic partition event */
191	    "\005XMMHC"		/* hypercall input through XMM regs */
192	    "\006IDLE"		/* guest idle support */
193	    "\007SLEEP"		/* hypervisor sleep support */
194	    "\010NUMA"		/* NUMA distance query support */
195	    "\011TMFREQ"	/* timer frequency query (TSC, LAPIC) */
196	    "\012SYNCMC"	/* inject synthetic machine checks */
197	    "\013CRASH"		/* MSRs for guest crash */
198	    "\014DEBUGMSR"	/* MSRs for guest debug */
199	    "\015NPIEP"		/* NPIEP */
200	    "\016HVDIS");	/* disabling hypervisor */
201
202	do_cpuid(CPUID_LEAF_HV_RECOMMENDS, regs);
203	hyperv_recommends = regs[0];
204	if (bootverbose)
205		printf("  Recommends: %08x %08x\n", regs[0], regs[1]);
206
207	do_cpuid(CPUID_LEAF_HV_LIMITS, regs);
208	if (bootverbose) {
209		printf("  Limits: Vcpu:%d Lcpu:%d Int:%d\n",
210		    regs[0], regs[1], regs[2]);
211	}
212
213	if (maxleaf >= CPUID_LEAF_HV_HWFEATURES) {
214		do_cpuid(CPUID_LEAF_HV_HWFEATURES, regs);
215		if (bootverbose) {
216			printf("  HW Features: %08x, AMD: %08x\n",
217			    regs[0], regs[3]);
218		}
219	}
220
221	return (true);
222}
223
224static void
225hyperv_init(void *dummy __unused)
226{
227	if (!hyperv_identify()) {
228		/* Not Hyper-V; reset guest id to the generic one. */
229		if (vm_guest == VM_GUEST_HV)
230			vm_guest = VM_GUEST_VM;
231		return;
232	}
233
234	/* Set guest id */
235	wrmsr(MSR_HV_GUEST_OS_ID, MSR_HV_GUESTID_FREEBSD);
236
237	if (hyperv_features & CPUID_HV_MSR_TIME_REFCNT) {
238		/* Register Hyper-V timecounter */
239		tc_init(&hyperv_timecounter);
240	}
241}
242SYSINIT(hyperv_initialize, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, hyperv_init,
243    NULL);
244
245static void
246hypercall_memfree(void)
247{
248	hyperv_dmamem_free(&hypercall_context.hc_dma,
249	    hypercall_context.hc_addr);
250	hypercall_context.hc_addr = NULL;
251}
252
253static void
254hypercall_create(void *arg __unused)
255{
256	uint64_t hc, hc_orig;
257
258	if (vm_guest != VM_GUEST_HV)
259		return;
260
261	hypercall_context.hc_addr = hyperv_dmamem_alloc(NULL, PAGE_SIZE, 0,
262	    PAGE_SIZE, &hypercall_context.hc_dma, BUS_DMA_WAITOK);
263	if (hypercall_context.hc_addr == NULL) {
264		printf("hyperv: Hypercall page allocation failed\n");
265		/* Can't perform any Hyper-V specific actions */
266		vm_guest = VM_GUEST_VM;
267		return;
268	}
269
270	/* Get the 'reserved' bits, which requires preservation. */
271	hc_orig = rdmsr(MSR_HV_HYPERCALL);
272
273	/*
274	 * Setup the Hypercall page.
275	 *
276	 * NOTE: 'reserved' bits MUST be preserved.
277	 */
278	hc = ((hypercall_context.hc_dma.hv_paddr >> PAGE_SHIFT) <<
279	    MSR_HV_HYPERCALL_PGSHIFT) |
280	    (hc_orig & MSR_HV_HYPERCALL_RSVD_MASK) |
281	    MSR_HV_HYPERCALL_ENABLE;
282	wrmsr(MSR_HV_HYPERCALL, hc);
283
284	/*
285	 * Confirm that Hypercall page did get setup.
286	 */
287	hc = rdmsr(MSR_HV_HYPERCALL);
288	if ((hc & MSR_HV_HYPERCALL_ENABLE) == 0) {
289		printf("hyperv: Hypercall setup failed\n");
290		hypercall_memfree();
291		/* Can't perform any Hyper-V specific actions */
292		vm_guest = VM_GUEST_VM;
293		return;
294	}
295	if (bootverbose)
296		printf("hyperv: Hypercall created\n");
297}
298SYSINIT(hypercall_ctor, SI_SUB_DRIVERS, SI_ORDER_FIRST, hypercall_create, NULL);
299
300static void
301hypercall_destroy(void *arg __unused)
302{
303	uint64_t hc;
304
305	if (hypercall_context.hc_addr == NULL)
306		return;
307
308	/* Disable Hypercall */
309	hc = rdmsr(MSR_HV_HYPERCALL);
310	wrmsr(MSR_HV_HYPERCALL, (hc & MSR_HV_HYPERCALL_RSVD_MASK));
311	hypercall_memfree();
312
313	if (bootverbose)
314		printf("hyperv: Hypercall destroyed\n");
315}
316SYSUNINIT(hypercall_dtor, SI_SUB_DRIVERS, SI_ORDER_FIRST, hypercall_destroy,
317    NULL);
318