1/*-
2 * Copyright (c) 2009-2012,2016-2017 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 Hyper-V/Azure
31 */
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: stable/10/sys/dev/hyperv/vmbus/hyperv.c 332067 2018-04-05 12:59:49Z emaste $");
34
35#include <sys/param.h>
36#include <sys/kernel.h>
37#include <sys/malloc.h>
38#include <sys/systm.h>
39#include <sys/timetc.h>
40
41#include <vm/vm.h>
42#include <vm/vm_extern.h>
43#include <vm/vm_kern.h>
44#include <vm/pmap.h>
45
46#include <dev/hyperv/include/hyperv.h>
47#include <dev/hyperv/include/hyperv_busdma.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
52#define HYPERV_FREEBSD_BUILD		0ULL
53#define HYPERV_FREEBSD_VERSION		((uint64_t)__FreeBSD_version)
54#define HYPERV_FREEBSD_OSID		0ULL
55
56#define MSR_HV_GUESTID_BUILD_FREEBSD	\
57	(HYPERV_FREEBSD_BUILD & MSR_HV_GUESTID_BUILD_MASK)
58#define MSR_HV_GUESTID_VERSION_FREEBSD	\
59	((HYPERV_FREEBSD_VERSION << MSR_HV_GUESTID_VERSION_SHIFT) & \
60	 MSR_HV_GUESTID_VERSION_MASK)
61#define MSR_HV_GUESTID_OSID_FREEBSD	\
62	((HYPERV_FREEBSD_OSID << MSR_HV_GUESTID_OSID_SHIFT) & \
63	 MSR_HV_GUESTID_OSID_MASK)
64
65#define MSR_HV_GUESTID_FREEBSD		\
66	(MSR_HV_GUESTID_BUILD_FREEBSD |	\
67	 MSR_HV_GUESTID_VERSION_FREEBSD | \
68	 MSR_HV_GUESTID_OSID_FREEBSD |	\
69	 MSR_HV_GUESTID_OSTYPE_FREEBSD)
70
71struct hypercall_ctx {
72	void			*hc_addr;
73	vm_paddr_t		hc_paddr;
74};
75
76static u_int			hyperv_get_timecount(struct timecounter *);
77static bool			hyperv_identify(void);
78static void			hypercall_memfree(void);
79
80u_int				hyperv_ver_major;
81
82u_int				hyperv_features;
83u_int				hyperv_recommends;
84
85static u_int			hyperv_pm_features;
86static u_int			hyperv_features3;
87
88hyperv_tc64_t			hyperv_tc64;
89
90static struct timecounter	hyperv_timecounter = {
91	.tc_get_timecount	= hyperv_get_timecount,
92	.tc_poll_pps		= NULL,
93	.tc_counter_mask	= 0xffffffff,
94	.tc_frequency		= HYPERV_TIMER_FREQ,
95	.tc_name		= "Hyper-V",
96	.tc_quality		= 2000,
97	.tc_flags		= 0,
98	.tc_priv		= NULL
99};
100
101static struct hypercall_ctx	hypercall_context;
102
103static u_int
104hyperv_get_timecount(struct timecounter *tc __unused)
105{
106	return rdmsr(MSR_HV_TIME_REF_COUNT);
107}
108
109static uint64_t
110hyperv_tc64_rdmsr(void)
111{
112
113	return (rdmsr(MSR_HV_TIME_REF_COUNT));
114}
115
116uint64_t
117hypercall_post_message(bus_addr_t msg_paddr)
118{
119	return hypercall_md(hypercall_context.hc_addr,
120	    HYPERCALL_POST_MESSAGE, msg_paddr, 0);
121}
122
123uint64_t
124hypercall_signal_event(bus_addr_t monprm_paddr)
125{
126	return hypercall_md(hypercall_context.hc_addr,
127	    HYPERCALL_SIGNAL_EVENT, monprm_paddr, 0);
128}
129
130int
131hyperv_guid2str(const struct hyperv_guid *guid, char *buf, size_t sz)
132{
133	const uint8_t *d = guid->hv_guid;
134
135	return snprintf(buf, sz, "%02x%02x%02x%02x-"
136	    "%02x%02x-%02x%02x-%02x%02x-"
137	    "%02x%02x%02x%02x%02x%02x",
138	    d[3], d[2], d[1], d[0],
139	    d[5], d[4], d[7], d[6], d[8], d[9],
140	    d[10], d[11], d[12], d[13], d[14], d[15]);
141}
142
143static bool
144hyperv_identify(void)
145{
146	u_int regs[4];
147	unsigned int maxleaf;
148
149	if (vm_guest != VM_GUEST_HV)
150		return (false);
151
152	do_cpuid(CPUID_LEAF_HV_MAXLEAF, regs);
153	maxleaf = regs[0];
154	if (maxleaf < CPUID_LEAF_HV_LIMITS)
155		return (false);
156
157	do_cpuid(CPUID_LEAF_HV_INTERFACE, regs);
158	if (regs[0] != CPUID_HV_IFACE_HYPERV)
159		return (false);
160
161	do_cpuid(CPUID_LEAF_HV_FEATURES, regs);
162	if ((regs[0] & CPUID_HV_MSR_HYPERCALL) == 0) {
163		/*
164		 * Hyper-V w/o Hypercall is impossible; someone
165		 * is faking Hyper-V.
166		 */
167		return (false);
168	}
169	hyperv_features = regs[0];
170	hyperv_pm_features = regs[2];
171	hyperv_features3 = regs[3];
172
173	do_cpuid(CPUID_LEAF_HV_IDENTITY, regs);
174	hyperv_ver_major = regs[1] >> 16;
175	printf("Hyper-V Version: %d.%d.%d [SP%d]\n",
176	    hyperv_ver_major, regs[1] & 0xffff, regs[0], regs[2]);
177
178	printf("  Features=0x%b\n", hyperv_features,
179	    "\020"
180	    "\001VPRUNTIME"	/* MSR_HV_VP_RUNTIME */
181	    "\002TMREFCNT"	/* MSR_HV_TIME_REF_COUNT */
182	    "\003SYNIC"		/* MSRs for SynIC */
183	    "\004SYNTM"		/* MSRs for SynTimer */
184	    "\005APIC"		/* MSR_HV_{EOI,ICR,TPR} */
185	    "\006HYPERCALL"	/* MSR_HV_{GUEST_OS_ID,HYPERCALL} */
186	    "\007VPINDEX"	/* MSR_HV_VP_INDEX */
187	    "\010RESET"		/* MSR_HV_RESET */
188	    "\011STATS"		/* MSR_HV_STATS_ */
189	    "\012REFTSC"	/* MSR_HV_REFERENCE_TSC */
190	    "\013IDLE"		/* MSR_HV_GUEST_IDLE */
191	    "\014TMFREQ"	/* MSR_HV_{TSC,APIC}_FREQUENCY */
192	    "\015DEBUG");	/* MSR_HV_SYNTH_DEBUG_ */
193	printf("  PM Features=0x%b [C%u]\n",
194	    (hyperv_pm_features & ~CPUPM_HV_CSTATE_MASK),
195	    "\020"
196	    "\005C3HPET",	/* HPET is required for C3 state */
197	    CPUPM_HV_CSTATE(hyperv_pm_features));
198	printf("  Features3=0x%b\n", hyperv_features3,
199	    "\020"
200	    "\001MWAIT"		/* MWAIT */
201	    "\002DEBUG"		/* guest debug support */
202	    "\003PERFMON"	/* performance monitor */
203	    "\004PCPUDPE"	/* physical CPU dynamic partition event */
204	    "\005XMMHC"		/* hypercall input through XMM regs */
205	    "\006IDLE"		/* guest idle support */
206	    "\007SLEEP"		/* hypervisor sleep support */
207	    "\010NUMA"		/* NUMA distance query support */
208	    "\011TMFREQ"	/* timer frequency query (TSC, LAPIC) */
209	    "\012SYNCMC"	/* inject synthetic machine checks */
210	    "\013CRASH"		/* MSRs for guest crash */
211	    "\014DEBUGMSR"	/* MSRs for guest debug */
212	    "\015NPIEP"		/* NPIEP */
213	    "\016HVDIS");	/* disabling hypervisor */
214
215	do_cpuid(CPUID_LEAF_HV_RECOMMENDS, regs);
216	hyperv_recommends = regs[0];
217	if (bootverbose)
218		printf("  Recommends: %08x %08x\n", regs[0], regs[1]);
219
220	do_cpuid(CPUID_LEAF_HV_LIMITS, regs);
221	if (bootverbose) {
222		printf("  Limits: Vcpu:%d Lcpu:%d Int:%d\n",
223		    regs[0], regs[1], regs[2]);
224	}
225
226	if (maxleaf >= CPUID_LEAF_HV_HWFEATURES) {
227		do_cpuid(CPUID_LEAF_HV_HWFEATURES, regs);
228		if (bootverbose) {
229			printf("  HW Features: %08x, AMD: %08x\n",
230			    regs[0], regs[3]);
231		}
232	}
233
234	return (true);
235}
236
237static void
238hyperv_init(void *dummy __unused)
239{
240	if (!hyperv_identify()) {
241		/* Not Hyper-V; reset guest id to the generic one. */
242		if (vm_guest == VM_GUEST_HV)
243			vm_guest = VM_GUEST_VM;
244		return;
245	}
246
247	/* Set guest id */
248	wrmsr(MSR_HV_GUEST_OS_ID, MSR_HV_GUESTID_FREEBSD);
249
250	if (hyperv_features & CPUID_HV_MSR_TIME_REFCNT) {
251		/* Register Hyper-V timecounter */
252		tc_init(&hyperv_timecounter);
253
254		/*
255		 * Install 64 bits timecounter method for other modules
256		 * to use.
257		 */
258		hyperv_tc64 = hyperv_tc64_rdmsr;
259	}
260}
261SYSINIT(hyperv_initialize, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, hyperv_init,
262    NULL);
263
264static void
265hypercall_memfree(void)
266{
267	kmem_free(kernel_arena, (vm_offset_t)hypercall_context.hc_addr,
268	    PAGE_SIZE);
269	hypercall_context.hc_addr = NULL;
270}
271
272static void
273hypercall_create(void *arg __unused)
274{
275	uint64_t hc, hc_orig;
276
277	if (vm_guest != VM_GUEST_HV)
278		return;
279
280	/*
281	 * NOTE:
282	 * - busdma(9), i.e. hyperv_dmamem APIs, can _not_ be used due to
283	 *   the NX bit.
284	 * - Assume kmem_malloc() returns properly aligned memory.
285	 */
286	hypercall_context.hc_addr = (void *)kmem_malloc(kernel_arena, PAGE_SIZE,
287	    M_WAITOK);
288	hypercall_context.hc_paddr = vtophys(hypercall_context.hc_addr);
289
290	/* Get the 'reserved' bits, which requires preservation. */
291	hc_orig = rdmsr(MSR_HV_HYPERCALL);
292
293	/*
294	 * Setup the Hypercall page.
295	 *
296	 * NOTE: 'reserved' bits MUST be preserved.
297	 */
298	hc = ((hypercall_context.hc_paddr >> PAGE_SHIFT) <<
299	    MSR_HV_HYPERCALL_PGSHIFT) |
300	    (hc_orig & MSR_HV_HYPERCALL_RSVD_MASK) |
301	    MSR_HV_HYPERCALL_ENABLE;
302	wrmsr(MSR_HV_HYPERCALL, hc);
303
304	/*
305	 * Confirm that Hypercall page did get setup.
306	 */
307	hc = rdmsr(MSR_HV_HYPERCALL);
308	if ((hc & MSR_HV_HYPERCALL_ENABLE) == 0) {
309		printf("hyperv: Hypercall setup failed\n");
310		hypercall_memfree();
311		/* Can't perform any Hyper-V specific actions */
312		vm_guest = VM_GUEST_VM;
313		return;
314	}
315	if (bootverbose)
316		printf("hyperv: Hypercall created\n");
317}
318SYSINIT(hypercall_ctor, SI_SUB_DRIVERS, SI_ORDER_FIRST, hypercall_create, NULL);
319
320static void
321hypercall_destroy(void *arg __unused)
322{
323	uint64_t hc;
324
325	if (hypercall_context.hc_addr == NULL)
326		return;
327
328	/* Disable Hypercall */
329	hc = rdmsr(MSR_HV_HYPERCALL);
330	wrmsr(MSR_HV_HYPERCALL, (hc & MSR_HV_HYPERCALL_RSVD_MASK));
331	hypercall_memfree();
332
333	if (bootverbose)
334		printf("hyperv: Hypercall destroyed\n");
335}
336SYSUNINIT(hypercall_dtor, SI_SUB_DRIVERS, SI_ORDER_FIRST, hypercall_destroy,
337    NULL);
338