xref: /illumos-gate/usr/src/cmd/bhyve/spinup_ap.c (revision c94be9439c4f0773ef60e2cec21d548359cfea20)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2012 NetApp, 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, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 /*
31  * This file and its contents are supplied under the terms of the
32  * Common Development and Distribution License ("CDDL"), version 1.0.
33  * You may only use this file in accordance with the terms of version
34  * 1.0 of the CDDL.
35  *
36  * A full copy of the text of the CDDL should have accompanied this
37  * source.  A copy of the CDDL is also available via the Internet at
38  * http://www.illumos.org/license/CDDL.
39  *
40  * Copyright 2020 Oxide Computer Company
41  */
42 
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 #include <sys/param.h>
47 #include <sys/types.h>
48 
49 #include <machine/vmm.h>
50 #include <vmmapi.h>
51 
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <assert.h>
55 
56 #include "bhyverun.h"
57 #include "spinup_ap.h"
58 
59 static void
60 spinup_ap_realmode(struct vmctx *ctx, int newcpu, uint64_t *rip)
61 {
62 	int vector, error;
63 	uint16_t cs;
64 	uint64_t desc_base;
65 	uint32_t desc_limit, desc_access;
66 
67 	vector = *rip >> PAGE_SHIFT;
68 	*rip = 0;
69 
70 	/*
71 	 * Update the %cs and %rip of the guest so that it starts
72 	 * executing real mode code at at 'vector << 12'.
73 	 */
74 	error = vm_set_register(ctx, newcpu, VM_REG_GUEST_RIP, *rip);
75 	assert(error == 0);
76 
77 	error = vm_get_desc(ctx, newcpu, VM_REG_GUEST_CS, &desc_base,
78 			    &desc_limit, &desc_access);
79 	assert(error == 0);
80 
81 	desc_base = vector << PAGE_SHIFT;
82 	error = vm_set_desc(ctx, newcpu, VM_REG_GUEST_CS,
83 			    desc_base, desc_limit, desc_access);
84 	assert(error == 0);
85 
86 	cs = (vector << PAGE_SHIFT) >> 4;
87 	error = vm_set_register(ctx, newcpu, VM_REG_GUEST_CS, cs);
88 	assert(error == 0);
89 }
90 
91 int
92 spinup_ap(struct vmctx *ctx, int vcpu, int newcpu, uint64_t rip)
93 {
94 	int error;
95 
96 	assert(newcpu != 0);
97 	assert(newcpu < guest_ncpus);
98 
99 	error = vcpu_reset(ctx, newcpu);
100 	assert(error == 0);
101 
102 	fbsdrun_set_capabilities(ctx, newcpu);
103 
104 #ifdef __FreeBSD__
105 	/*
106 	 * Enable the 'unrestricted guest' mode for 'newcpu'.
107 	 *
108 	 * Set up the processor state in power-on 16-bit mode, with the CS:IP
109 	 * init'd to the specified low-mem 4K page.
110 	 */
111 	error = vm_set_capability(ctx, newcpu, VM_CAP_UNRESTRICTED_GUEST, 1);
112 	assert(error == 0);
113 #else
114 	/* Unrestricted Guest is always enabled on illumos */
115 #endif
116 
117 	spinup_ap_realmode(ctx, newcpu, &rip);
118 
119 #ifdef __FreeBSD__
120 	fbsdrun_addcpu(ctx, vcpu, newcpu, rip);
121 #else
122 	fbsdrun_addcpu(ctx, vcpu, newcpu, rip, false);
123 #endif
124 
125 	return (newcpu);
126 }
127