1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright © 2008, 2013 Citrix Systems, Inc.
5 * Copyright © 2012 Spectra Logic Corporation
6 * Copyright © 2021 Elliott Mitchell
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 #include <sys/param.h> /* required by xen/xen-os.h */
33
34 #include <vm/vm.h>
35 #include <vm/pmap.h>
36
37 #include <machine/atomic.h> /* required by xen/xen-os.h */
38
39 #include <xen/xen-os.h>
40 #include <xen/hvm.h>
41
42 #include <contrib/xen/vcpu.h>
43
44 /*-------------------------------- Global Data -------------------------------*/
45 enum xen_domain_type xen_domain_type = XEN_NATIVE;
46
47 /**
48 * Start info flags. ATM this only used to store the initial domain flag for
49 * PVHv2, and it's always empty for HVM guests.
50 */
51 uint32_t hvm_start_flags;
52
53 /*------------------ Hypervisor Access Shared Memory Regions -----------------*/
54 shared_info_t *HYPERVISOR_shared_info;
55
56 /*------------------------------- Per-CPU Data -------------------------------*/
57 DPCPU_DEFINE(struct vcpu_info *, vcpu_info);
58
59 void
xen_setup_vcpu_info(void)60 xen_setup_vcpu_info(void)
61 {
62 /* This isn't directly accessed outside this function */
63 DPCPU_DEFINE_STATIC(vcpu_info_t, vcpu_local_info)
64 __attribute__((aligned(64)));
65
66 vcpu_info_t *vcpu_info = DPCPU_PTR(vcpu_local_info);
67 vcpu_register_vcpu_info_t info = {
68 .mfn = vtophys(vcpu_info) >> PAGE_SHIFT,
69 .offset = vtophys(vcpu_info) & PAGE_MASK,
70 };
71 unsigned int cpu = XEN_VCPUID();
72 int rc;
73
74 KASSERT(xen_domain(), ("%s(): invoked when not on Xen?", __func__));
75
76 _Static_assert(sizeof(struct vcpu_info) <= 64,
77 "struct vcpu_info is larger than supported limit of 64 bytes");
78
79 /*
80 * Set the vCPU info.
81 *
82 * NB: the vCPU info for some vCPUs can be fetched from the shared info
83 * page, but in order to make sure the mapping code is correct always
84 * attempt to map the vCPU info at a custom place.
85 */
86 rc = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
87 if (rc == 0)
88 DPCPU_SET(vcpu_info, vcpu_info);
89 else if (cpu < nitems(HYPERVISOR_shared_info->vcpu_info)) {
90 static bool warned = false;
91
92 DPCPU_SET(vcpu_info, &HYPERVISOR_shared_info->vcpu_info[cpu]);
93
94 if (bootverbose && !warned) {
95 warned = true;
96 printf(
97 "WARNING: Xen vCPU %u failed to setup vcpu_info rc = %d\n",
98 cpu, rc);
99 }
100 } else
101 panic("Unable to register vCPU %u, rc=%d\n", cpu, rc);
102 }
103