spinup_ap.c revision 330449 
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: stable/11/usr.sbin/bhyve/spinup_ap.c 330449 2018-03-05 07:26:05Z eadler $
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD: stable/11/usr.sbin/bhyve/spinup_ap.c 330449 2018-03-05 07:26:05Z eadler $");
33
34#include <sys/param.h>
35#include <sys/types.h>
36
37#include <machine/vmm.h>
38#include <vmmapi.h>
39
40#include <stdio.h>
41#include <stdlib.h>
42#include <assert.h>
43
44#include "bhyverun.h"
45#include "spinup_ap.h"
46
47static void
48spinup_ap_realmode(struct vmctx *ctx, int newcpu, uint64_t *rip)
49{
50	int vector, error;
51	uint16_t cs;
52	uint64_t desc_base;
53	uint32_t desc_limit, desc_access;
54
55	vector = *rip >> PAGE_SHIFT;
56	*rip = 0;
57
58	/*
59	 * Update the %cs and %rip of the guest so that it starts
60	 * executing real mode code at at 'vector << 12'.
61	 */
62	error = vm_set_register(ctx, newcpu, VM_REG_GUEST_RIP, *rip);
63	assert(error == 0);
64
65	error = vm_get_desc(ctx, newcpu, VM_REG_GUEST_CS, &desc_base,
66			    &desc_limit, &desc_access);
67	assert(error == 0);
68
69	desc_base = vector << PAGE_SHIFT;
70	error = vm_set_desc(ctx, newcpu, VM_REG_GUEST_CS,
71			    desc_base, desc_limit, desc_access);
72	assert(error == 0);
73
74	cs = (vector << PAGE_SHIFT) >> 4;
75	error = vm_set_register(ctx, newcpu, VM_REG_GUEST_CS, cs);
76	assert(error == 0);
77}
78
79int
80spinup_ap(struct vmctx *ctx, int vcpu, int newcpu, uint64_t rip)
81{
82	int error;
83
84	assert(newcpu != 0);
85	assert(newcpu < guest_ncpus);
86
87	error = vcpu_reset(ctx, newcpu);
88	assert(error == 0);
89
90	fbsdrun_set_capabilities(ctx, newcpu);
91
92	/*
93	 * Enable the 'unrestricted guest' mode for 'newcpu'.
94	 *
95	 * Set up the processor state in power-on 16-bit mode, with the CS:IP
96	 * init'd to the specified low-mem 4K page.
97	 */
98	error = vm_set_capability(ctx, newcpu, VM_CAP_UNRESTRICTED_GUEST, 1);
99	assert(error == 0);
100
101	spinup_ap_realmode(ctx, newcpu, &rip);
102
103	fbsdrun_addcpu(ctx, vcpu, newcpu, rip);
104
105	return (newcpu);
106}
107