1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * svm_vmcall_test
4  *
5  * Copyright © 2021 Amazon.com, Inc. or its affiliates.
6  *
7  * Xen shared_info / pvclock testing
8  */
9 
10 #include "test_util.h"
11 #include "kvm_util.h"
12 #include "processor.h"
13 
14 #include <stdint.h>
15 #include <time.h>
16 
17 #define VCPU_ID		5
18 
19 #define SHINFO_REGION_GPA	0xc0000000ULL
20 #define SHINFO_REGION_SLOT	10
21 #define PAGE_SIZE		4096
22 
23 #define PVTIME_ADDR	(SHINFO_REGION_GPA + PAGE_SIZE)
24 
25 static struct kvm_vm *vm;
26 
27 #define XEN_HYPERCALL_MSR	0x40000000
28 
29 struct pvclock_vcpu_time_info {
30         u32   version;
31         u32   pad0;
32         u64   tsc_timestamp;
33         u64   system_time;
34         u32   tsc_to_system_mul;
35         s8    tsc_shift;
36         u8    flags;
37         u8    pad[2];
38 } __attribute__((__packed__)); /* 32 bytes */
39 
40 struct pvclock_wall_clock {
41         u32   version;
42         u32   sec;
43         u32   nsec;
44 } __attribute__((__packed__));
45 
46 static void guest_code(void)
47 {
48 	GUEST_DONE();
49 }
50 
51 static int cmp_timespec(struct timespec *a, struct timespec *b)
52 {
53 	if (a->tv_sec > b->tv_sec)
54 		return 1;
55 	else if (a->tv_sec < b->tv_sec)
56 		return -1;
57 	else if (a->tv_nsec > b->tv_nsec)
58 		return 1;
59 	else if (a->tv_nsec < b->tv_nsec)
60 		return -1;
61 	else
62 		return 0;
63 }
64 
65 int main(int argc, char *argv[])
66 {
67 	struct timespec min_ts, max_ts, vm_ts;
68 
69 	if (!(kvm_check_cap(KVM_CAP_XEN_HVM) &
70 	      KVM_XEN_HVM_CONFIG_SHARED_INFO) ) {
71 		print_skip("KVM_XEN_HVM_CONFIG_SHARED_INFO not available");
72 		exit(KSFT_SKIP);
73 	}
74 
75 	clock_gettime(CLOCK_REALTIME, &min_ts);
76 
77 	vm = vm_create_default(VCPU_ID, 0, (void *) guest_code);
78 	vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
79 
80 	/* Map a region for the shared_info page */
81 	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
82 				    SHINFO_REGION_GPA, SHINFO_REGION_SLOT, 2, 0);
83 
84 	struct kvm_xen_hvm_config hvmc = {
85 		.flags = KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL,
86 		.msr = XEN_HYPERCALL_MSR,
87 	};
88 	vm_ioctl(vm, KVM_XEN_HVM_CONFIG, &hvmc);
89 
90 	struct kvm_xen_hvm_attr lm = {
91 		.type = KVM_XEN_ATTR_TYPE_LONG_MODE,
92 		.u.long_mode = 1,
93 	};
94 	vm_ioctl(vm, KVM_XEN_HVM_SET_ATTR, &lm);
95 
96 	struct kvm_xen_hvm_attr ha = {
97 		.type = KVM_XEN_ATTR_TYPE_SHARED_INFO,
98 		.u.shared_info.gfn = SHINFO_REGION_GPA / PAGE_SIZE,
99 	};
100 	vm_ioctl(vm, KVM_XEN_HVM_SET_ATTR, &ha);
101 
102 	struct kvm_xen_vcpu_attr vi = {
103 		.type = KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO,
104 		.u.gpa = SHINFO_REGION_GPA + 0x40,
105 	};
106 	vcpu_ioctl(vm, VCPU_ID, KVM_XEN_VCPU_SET_ATTR, &vi);
107 
108 	struct kvm_xen_vcpu_attr pvclock = {
109 		.type = KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO,
110 		.u.gpa = PVTIME_ADDR,
111 	};
112 	vcpu_ioctl(vm, VCPU_ID, KVM_XEN_VCPU_SET_ATTR, &pvclock);
113 
114 	for (;;) {
115 		volatile struct kvm_run *run = vcpu_state(vm, VCPU_ID);
116 		struct ucall uc;
117 
118 		vcpu_run(vm, VCPU_ID);
119 
120 		TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
121 			    "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n",
122 			    run->exit_reason,
123 			    exit_reason_str(run->exit_reason));
124 
125 		switch (get_ucall(vm, VCPU_ID, &uc)) {
126 		case UCALL_ABORT:
127 			TEST_FAIL("%s", (const char *)uc.args[0]);
128 			/* NOT REACHED */
129 		case UCALL_SYNC:
130 			break;
131 		case UCALL_DONE:
132 			goto done;
133 		default:
134 			TEST_FAIL("Unknown ucall 0x%lx.", uc.cmd);
135 		}
136 	}
137 
138  done:
139 	clock_gettime(CLOCK_REALTIME, &max_ts);
140 
141 	/*
142 	 * Just a *really* basic check that things are being put in the
143 	 * right place. The actual calculations are much the same for
144 	 * Xen as they are for the KVM variants, so no need to check.
145 	 */
146 	struct pvclock_wall_clock *wc;
147 	struct pvclock_vcpu_time_info *ti, *ti2;
148 
149 	wc = addr_gpa2hva(vm, SHINFO_REGION_GPA + 0xc00);
150 	ti = addr_gpa2hva(vm, SHINFO_REGION_GPA + 0x40 + 0x20);
151 	ti2 = addr_gpa2hva(vm, PVTIME_ADDR);
152 
153 	vm_ts.tv_sec = wc->sec;
154 	vm_ts.tv_nsec = wc->nsec;
155         TEST_ASSERT(wc->version && !(wc->version & 1),
156 		    "Bad wallclock version %x", wc->version);
157 	TEST_ASSERT(cmp_timespec(&min_ts, &vm_ts) <= 0, "VM time too old");
158 	TEST_ASSERT(cmp_timespec(&max_ts, &vm_ts) >= 0, "VM time too new");
159 
160 	TEST_ASSERT(ti->version && !(ti->version & 1),
161 		    "Bad time_info version %x", ti->version);
162 	TEST_ASSERT(ti2->version && !(ti2->version & 1),
163 		    "Bad time_info version %x", ti->version);
164 
165 	kvm_vm_free(vm);
166 	return 0;
167 }
168