xref: /linux/tools/testing/selftests/kvm/s390x/memop.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Test for s390x KVM_S390_MEM_OP
4  *
5  * Copyright (C) 2019, Red Hat, Inc.
6  */
7 
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <string.h>
11 #include <sys/ioctl.h>
12 
13 #include "test_util.h"
14 #include "kvm_util.h"
15 
16 #define VCPU_ID 1
17 
18 static uint8_t mem1[65536];
19 static uint8_t mem2[65536];
20 
21 static void guest_code(void)
22 {
23 	int i;
24 
25 	for (;;) {
26 		for (i = 0; i < sizeof(mem2); i++)
27 			mem2[i] = mem1[i];
28 		GUEST_SYNC(0);
29 	}
30 }
31 
32 int main(int argc, char *argv[])
33 {
34 	struct kvm_vm *vm;
35 	struct kvm_run *run;
36 	struct kvm_s390_mem_op ksmo;
37 	int rv, i, maxsize;
38 
39 	setbuf(stdout, NULL);	/* Tell stdout not to buffer its content */
40 
41 	maxsize = kvm_check_cap(KVM_CAP_S390_MEM_OP);
42 	if (!maxsize) {
43 		fprintf(stderr, "CAP_S390_MEM_OP not supported -> skip test\n");
44 		exit(KSFT_SKIP);
45 	}
46 	if (maxsize > sizeof(mem1))
47 		maxsize = sizeof(mem1);
48 
49 	/* Create VM */
50 	vm = vm_create_default(VCPU_ID, 0, guest_code);
51 	run = vcpu_state(vm, VCPU_ID);
52 
53 	for (i = 0; i < sizeof(mem1); i++)
54 		mem1[i] = i * i + i;
55 
56 	/* Set the first array */
57 	ksmo.gaddr = addr_gva2gpa(vm, (uintptr_t)mem1);
58 	ksmo.flags = 0;
59 	ksmo.size = maxsize;
60 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
61 	ksmo.buf = (uintptr_t)mem1;
62 	ksmo.ar = 0;
63 	vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
64 
65 	/* Let the guest code copy the first array to the second */
66 	vcpu_run(vm, VCPU_ID);
67 	TEST_ASSERT(run->exit_reason == KVM_EXIT_S390_SIEIC,
68 		    "Unexpected exit reason: %u (%s)\n",
69 		    run->exit_reason,
70 		    exit_reason_str(run->exit_reason));
71 
72 	memset(mem2, 0xaa, sizeof(mem2));
73 
74 	/* Get the second array */
75 	ksmo.gaddr = (uintptr_t)mem2;
76 	ksmo.flags = 0;
77 	ksmo.size = maxsize;
78 	ksmo.op = KVM_S390_MEMOP_LOGICAL_READ;
79 	ksmo.buf = (uintptr_t)mem2;
80 	ksmo.ar = 0;
81 	vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
82 
83 	TEST_ASSERT(!memcmp(mem1, mem2, maxsize),
84 		    "Memory contents do not match!");
85 
86 	/* Check error conditions - first bad size: */
87 	ksmo.gaddr = (uintptr_t)mem1;
88 	ksmo.flags = 0;
89 	ksmo.size = -1;
90 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
91 	ksmo.buf = (uintptr_t)mem1;
92 	ksmo.ar = 0;
93 	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
94 	TEST_ASSERT(rv == -1 && errno == E2BIG, "ioctl allows insane sizes");
95 
96 	/* Zero size: */
97 	ksmo.gaddr = (uintptr_t)mem1;
98 	ksmo.flags = 0;
99 	ksmo.size = 0;
100 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
101 	ksmo.buf = (uintptr_t)mem1;
102 	ksmo.ar = 0;
103 	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
104 	TEST_ASSERT(rv == -1 && (errno == EINVAL || errno == ENOMEM),
105 		    "ioctl allows 0 as size");
106 
107 	/* Bad flags: */
108 	ksmo.gaddr = (uintptr_t)mem1;
109 	ksmo.flags = -1;
110 	ksmo.size = maxsize;
111 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
112 	ksmo.buf = (uintptr_t)mem1;
113 	ksmo.ar = 0;
114 	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
115 	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows all flags");
116 
117 	/* Bad operation: */
118 	ksmo.gaddr = (uintptr_t)mem1;
119 	ksmo.flags = 0;
120 	ksmo.size = maxsize;
121 	ksmo.op = -1;
122 	ksmo.buf = (uintptr_t)mem1;
123 	ksmo.ar = 0;
124 	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
125 	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows bad operations");
126 
127 	/* Bad guest address: */
128 	ksmo.gaddr = ~0xfffUL;
129 	ksmo.flags = KVM_S390_MEMOP_F_CHECK_ONLY;
130 	ksmo.size = maxsize;
131 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
132 	ksmo.buf = (uintptr_t)mem1;
133 	ksmo.ar = 0;
134 	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
135 	TEST_ASSERT(rv > 0, "ioctl does not report bad guest memory access");
136 
137 	/* Bad host address: */
138 	ksmo.gaddr = (uintptr_t)mem1;
139 	ksmo.flags = 0;
140 	ksmo.size = maxsize;
141 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
142 	ksmo.buf = 0;
143 	ksmo.ar = 0;
144 	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
145 	TEST_ASSERT(rv == -1 && errno == EFAULT,
146 		    "ioctl does not report bad host memory address");
147 
148 	/* Bad access register: */
149 	run->psw_mask &= ~(3UL << (63 - 17));
150 	run->psw_mask |= 1UL << (63 - 17);  /* Enable AR mode */
151 	vcpu_run(vm, VCPU_ID);              /* To sync new state to SIE block */
152 	ksmo.gaddr = (uintptr_t)mem1;
153 	ksmo.flags = 0;
154 	ksmo.size = maxsize;
155 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
156 	ksmo.buf = (uintptr_t)mem1;
157 	ksmo.ar = 17;
158 	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
159 	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows ARs > 15");
160 	run->psw_mask &= ~(3UL << (63 - 17));   /* Disable AR mode */
161 	vcpu_run(vm, VCPU_ID);                  /* Run to sync new state */
162 
163 	kvm_vm_free(vm);
164 
165 	return 0;
166 }
167