xref: /freebsd/sys/dev/hyperv/vmbus/hyperv.c (revision 7937bfbc0ca53fe7cdd0d54414f9296e273a518e)
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 
33 #include <sys/param.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/systm.h>
37 #include <sys/timetc.h>
38 #include <sys/cpuset.h>
39 
40 #include <vm/vm.h>
41 #include <vm/vm_extern.h>
42 #include <vm/vm_kern.h>
43 #include <vm/pmap.h>
44 
45 #include <dev/hyperv/include/hyperv.h>
46 #include <dev/hyperv/include/hyperv_busdma.h>
47 #if defined(__aarch64__)
48 #include <dev/hyperv/vmbus/aarch64/hyperv_machdep.h>
49 #include <dev/hyperv/vmbus/aarch64/hyperv_reg.h>
50 #else
51 #include <dev/hyperv/vmbus/x86/hyperv_machdep.h>
52 #include <dev/hyperv/vmbus/x86/hyperv_reg.h>
53 #endif
54 #include <dev/hyperv/vmbus/vmbus_var.h>
55 #include <dev/hyperv/vmbus/hyperv_common_reg.h>
56 #include <dev/hyperv/vmbus/hyperv_var.h>
57 
58 #define HYPERV_FREEBSD_BUILD		0ULL
59 #define HYPERV_FREEBSD_VERSION		((uint64_t)__FreeBSD_version)
60 #define HYPERV_FREEBSD_OSID		0ULL
61 
62 #define MSR_HV_GUESTID_BUILD_FREEBSD	\
63 	(HYPERV_FREEBSD_BUILD & MSR_HV_GUESTID_BUILD_MASK)
64 #define MSR_HV_GUESTID_VERSION_FREEBSD	\
65 	((HYPERV_FREEBSD_VERSION << MSR_HV_GUESTID_VERSION_SHIFT) & \
66 	 MSR_HV_GUESTID_VERSION_MASK)
67 #define MSR_HV_GUESTID_OSID_FREEBSD	\
68 	((HYPERV_FREEBSD_OSID << MSR_HV_GUESTID_OSID_SHIFT) & \
69 	 MSR_HV_GUESTID_OSID_MASK)
70 
71 #define MSR_HV_GUESTID_FREEBSD		\
72 	(MSR_HV_GUESTID_BUILD_FREEBSD |	\
73 	 MSR_HV_GUESTID_VERSION_FREEBSD | \
74 	 MSR_HV_GUESTID_OSID_FREEBSD |	\
75 	 MSR_HV_GUESTID_OSTYPE_FREEBSD)
76 
77 
78 static bool			hyperv_identify(void);
79 static void			hypercall_memfree(void);
80 
81 static struct hypercall_ctx	hypercall_context;
82 
83 uint64_t
84 hypercall_post_message(bus_addr_t msg_paddr)
85 {
86 	return hypercall_md(hypercall_context.hc_addr,
87 	    HYPERCALL_POST_MESSAGE, msg_paddr, 0);
88 }
89 
90 uint64_t
91 hypercall_signal_event(bus_addr_t monprm_paddr)
92 {
93 	return hypercall_md(hypercall_context.hc_addr,
94 	    HYPERCALL_SIGNAL_EVENT, monprm_paddr, 0);
95 }
96 
97 static inline int hv_result(uint64_t status)
98 {
99 	return status & HV_HYPERCALL_RESULT_MASK;
100 }
101 
102 static inline bool hv_result_success(uint64_t status)
103 {
104 	return hv_result(status) == HV_STATUS_SUCCESS;
105 }
106 
107 static inline unsigned int hv_repcomp(uint64_t status)
108 {
109 	/* Bits [43:32] of status have 'Reps completed' data. */
110 	return ((status & HV_HYPERCALL_REP_COMP_MASK) >>
111 	    HV_HYPERCALL_REP_COMP_OFFSET);
112 }
113 
114 /*
115  * Rep hypercalls. Callers of this functions are supposed to ensure that
116  * rep_count and varhead_size comply with Hyper-V hypercall definition.
117  */
118 uint64_t
119 hv_do_rep_hypercall(uint16_t code, uint16_t rep_count, uint16_t varhead_size,
120     uint64_t input, uint64_t output)
121 {
122 	uint64_t control = code;
123 	uint64_t status;
124 	uint16_t rep_comp;
125 
126 	control |= (uint64_t)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET;
127 	control |= (uint64_t)rep_count << HV_HYPERCALL_REP_COMP_OFFSET;
128 
129 	do {
130 		status = hypercall_do_md(control, input, output);
131 		if (!hv_result_success(status))
132 			return status;
133 
134 		rep_comp = hv_repcomp(status);
135 
136 		control &= ~HV_HYPERCALL_REP_START_MASK;
137 		control |= (uint64_t)rep_comp << HV_HYPERCALL_REP_START_OFFSET;
138 
139 	} while (rep_comp < rep_count);
140 	if (hv_result_success(status))
141 		return HV_STATUS_SUCCESS;
142 
143 	return status;
144 }
145 
146 uint64_t
147 hypercall_do_md(uint64_t input_val, uint64_t input_addr, uint64_t out_addr)
148 {
149 	uint64_t phys_inaddr, phys_outaddr;
150 	phys_inaddr = input_addr ? vtophys(input_addr) : 0;
151 	phys_outaddr = out_addr ? vtophys(out_addr) : 0;
152 	return hypercall_md(hypercall_context.hc_addr,
153 	    input_val, phys_inaddr, phys_outaddr);
154 }
155 
156 int
157 hyperv_guid2str(const struct hyperv_guid *guid, char *buf, size_t sz)
158 {
159 	const uint8_t *d = guid->hv_guid;
160 
161 	return snprintf(buf, sz, "%02x%02x%02x%02x-"
162 	    "%02x%02x-%02x%02x-%02x%02x-"
163 	    "%02x%02x%02x%02x%02x%02x",
164 	    d[3], d[2], d[1], d[0],
165 	    d[5], d[4], d[7], d[6], d[8], d[9],
166 	    d[10], d[11], d[12], d[13], d[14], d[15]);
167 }
168 
169 static bool
170 hyperv_identify(void)
171 {
172 	return(hyperv_identify_features());
173 }
174 static void
175 hyperv_init(void *dummy __unused)
176 {
177 	if (!hyperv_identify()) {
178 		/* Not Hyper-V; reset guest id to the generic one. */
179 		if (vm_guest == VM_GUEST_HV)
180 			vm_guest = VM_GUEST_VM;
181 		return;
182 	}
183 
184 	/* Set guest id */
185 	WRMSR(MSR_HV_GUEST_OS_ID, MSR_HV_GUESTID_FREEBSD);
186 	hyperv_init_tc();
187 }
188 SYSINIT(hyperv_initialize, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, hyperv_init,
189     NULL);
190 
191 static void
192 hypercall_memfree(void)
193 {
194 	kmem_free(hypercall_context.hc_addr, PAGE_SIZE);
195 	hypercall_context.hc_addr = NULL;
196 }
197 
198 static void
199 hypercall_create(void *arg __unused)
200 {
201 
202 	int ret;
203 	if (vm_guest != VM_GUEST_HV)
204 		return;
205 
206 	/*
207 	 * NOTE:
208 	 * - busdma(9), i.e. hyperv_dmamem APIs, can _not_ be used due to
209 	 *   the NX bit.
210 	 * - Assume kmem_malloc() returns properly aligned memory.
211 	 */
212 	hypercall_context.hc_addr = kmem_malloc(PAGE_SIZE, M_EXEC | M_WAITOK);
213 	hypercall_context.hc_paddr = vtophys(hypercall_context.hc_addr);
214 	ret = hypercall_page_setup(hypercall_context.hc_paddr);
215 	if (ret) {
216 		hypercall_memfree();
217 		return;
218 	}
219 	if (bootverbose)
220 		printf("hyperv: Hypercall created\n");
221 }
222 SYSINIT(hypercall_ctor, SI_SUB_DRIVERS, SI_ORDER_FIRST, hypercall_create, NULL);
223 
224 static void
225 hypercall_destroy(void *arg __unused)
226 {
227 
228 	if (hypercall_context.hc_addr == NULL)
229 		return;
230 	hypercall_disable();
231 	hypercall_memfree();
232 	if (bootverbose)
233 		printf("hyperv: Hypercall destroyed\n");
234 }
235 SYSUNINIT(hypercall_dtor, SI_SUB_DRIVERS, SI_ORDER_FIRST, hypercall_destroy,
236     NULL);
237