xref: /openbmc/linux/arch/x86/kvm/debugfs.c (revision e3d786a3)
1 /*
2  * Kernel-based Virtual Machine driver for Linux
3  *
4  * Copyright 2016 Red Hat, Inc. and/or its affiliates.
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2.  See
7  * the COPYING file in the top-level directory.
8  *
9  */
10 #include <linux/kvm_host.h>
11 #include <linux/debugfs.h>
12 
13 bool kvm_arch_has_vcpu_debugfs(void)
14 {
15 	return true;
16 }
17 
18 static int vcpu_get_tsc_offset(void *data, u64 *val)
19 {
20 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
21 	*val = vcpu->arch.tsc_offset;
22 	return 0;
23 }
24 
25 DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_offset_fops, vcpu_get_tsc_offset, NULL, "%lld\n");
26 
27 static int vcpu_get_tsc_scaling_ratio(void *data, u64 *val)
28 {
29 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
30 	*val = vcpu->arch.tsc_scaling_ratio;
31 	return 0;
32 }
33 
34 DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_scaling_fops, vcpu_get_tsc_scaling_ratio, NULL, "%llu\n");
35 
36 static int vcpu_get_tsc_scaling_frac_bits(void *data, u64 *val)
37 {
38 	*val = kvm_tsc_scaling_ratio_frac_bits;
39 	return 0;
40 }
41 
42 DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_scaling_frac_fops, vcpu_get_tsc_scaling_frac_bits, NULL, "%llu\n");
43 
44 int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
45 {
46 	struct dentry *ret;
47 
48 	ret = debugfs_create_file("tsc-offset", 0444,
49 							vcpu->debugfs_dentry,
50 							vcpu, &vcpu_tsc_offset_fops);
51 	if (!ret)
52 		return -ENOMEM;
53 
54 	if (kvm_has_tsc_control) {
55 		ret = debugfs_create_file("tsc-scaling-ratio", 0444,
56 							vcpu->debugfs_dentry,
57 							vcpu, &vcpu_tsc_scaling_fops);
58 		if (!ret)
59 			return -ENOMEM;
60 		ret = debugfs_create_file("tsc-scaling-ratio-frac-bits", 0444,
61 							vcpu->debugfs_dentry,
62 							vcpu, &vcpu_tsc_scaling_frac_fops);
63 		if (!ret)
64 			return -ENOMEM;
65 
66 	}
67 
68 	return 0;
69 }
70