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/param.h> /* required by xen/xen-os.h */
32
33 #include <vm/vm.h>
34 #include <vm/pmap.h>
35
36 #include <machine/atomic.h> /* required by xen/xen-os.h */
37
38 #include <xen/xen-os.h>
39 #include <xen/hvm.h>
40
41 #include <contrib/xen/vcpu.h>
42
43 /*-------------------------------- Global Data -------------------------------*/
44 /**
45 * Start info flags. ATM this only used to store the initial domain flag for
46 * PVHv2, and it's always empty for HVM guests.
47 */
48 uint32_t hvm_start_flags;
49
50 /*------------------ Hypervisor Access Shared Memory Regions -----------------*/
51 shared_info_t *HYPERVISOR_shared_info;
52
53 /*------------------------------- Per-CPU Data -------------------------------*/
54 DPCPU_DEFINE(struct vcpu_info *, vcpu_info);
55
56 void
xen_setup_vcpu_info(void)57 xen_setup_vcpu_info(void)
58 {
59 /* This isn't directly accessed outside this function */
60 DPCPU_DEFINE_STATIC(vcpu_info_t, vcpu_local_info)
61 __attribute__((aligned(64)));
62
63 vcpu_info_t *vcpu_info = DPCPU_PTR(vcpu_local_info);
64 vcpu_register_vcpu_info_t info = {
65 .mfn = vtophys(vcpu_info) >> PAGE_SHIFT,
66 .offset = vtophys(vcpu_info) & PAGE_MASK,
67 };
68 unsigned int cpu = XEN_VCPUID();
69 int rc;
70
71 KASSERT(xen_domain(), ("%s(): invoked when not on Xen?", __func__));
72
73 _Static_assert(sizeof(struct vcpu_info) <= 64,
74 "struct vcpu_info is larger than supported limit of 64 bytes");
75
76 /*
77 * Set the vCPU info.
78 *
79 * NB: the vCPU info for some vCPUs can be fetched from the shared info
80 * page, but in order to make sure the mapping code is correct always
81 * attempt to map the vCPU info at a custom place.
82 */
83 rc = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
84 if (rc == 0)
85 DPCPU_SET(vcpu_info, vcpu_info);
86 else if (cpu < nitems(HYPERVISOR_shared_info->vcpu_info)) {
87 static bool warned = false;
88
89 DPCPU_SET(vcpu_info, &HYPERVISOR_shared_info->vcpu_info[cpu]);
90
91 if (bootverbose && !warned) {
92 warned = true;
93 printf(
94 "WARNING: Xen vCPU %u failed to setup vcpu_info rc = %d\n",
95 cpu, rc);
96 }
97 } else
98 panic("Unable to register vCPU %u, rc=%d\n", cpu, rc);
99 }
100