summaryrefslogtreecommitdiffstats
path: root/arch/riscv/kvm/vcpu_fp.c
blob: 030904d82b583e1ce3f4e44cdabe4e61e708e616 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2021 Western Digital Corporation or its affiliates.
 *
 * Authors:
 *     Atish Patra <atish.patra@wdc.com>
 *     Anup Patel <anup.patel@wdc.com>
 */

#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
#include <linux/uaccess.h>
#include <asm/cpufeature.h>

#ifdef CONFIG_FPU
void kvm_riscv_vcpu_fp_reset(struct kvm_vcpu *vcpu)
{
	struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;

	cntx->sstatus &= ~SR_FS;
	if (riscv_isa_extension_available(vcpu->arch.isa, f) ||
	    riscv_isa_extension_available(vcpu->arch.isa, d))
		cntx->sstatus |= SR_FS_INITIAL;
	else
		cntx->sstatus |= SR_FS_OFF;
}

static void kvm_riscv_vcpu_fp_clean(struct kvm_cpu_context *cntx)
{
	cntx->sstatus &= ~SR_FS;
	cntx->sstatus |= SR_FS_CLEAN;
}

void kvm_riscv_vcpu_guest_fp_save(struct kvm_cpu_context *cntx,
				  const unsigned long *isa)
{
	if ((cntx->sstatus & SR_FS) == SR_FS_DIRTY) {
		if (riscv_isa_extension_available(isa, d))
			__kvm_riscv_fp_d_save(cntx);
		else if (riscv_isa_extension_available(isa, f))
			__kvm_riscv_fp_f_save(cntx);
		kvm_riscv_vcpu_fp_clean(cntx);
	}
}

void kvm_riscv_vcpu_guest_fp_restore(struct kvm_cpu_context *cntx,
				     const unsigned long *isa)
{
	if ((cntx->sstatus & SR_FS) != SR_FS_OFF) {
		if (riscv_isa_extension_available(isa, d))
			__kvm_riscv_fp_d_restore(cntx);
		else if (riscv_isa_extension_available(isa, f))
			__kvm_riscv_fp_f_restore(cntx);
		kvm_riscv_vcpu_fp_clean(cntx);
	}
}

void kvm_riscv_vcpu_host_fp_save(struct kvm_cpu_context *cntx)
{
	/* No need to check host sstatus as it can be modified outside */
	if (riscv_isa_extension_available(NULL, d))
		__kvm_riscv_fp_d_save(cntx);
	else if (riscv_isa_extension_available(NULL, f))
		__kvm_riscv_fp_f_save(cntx);
}

void kvm_riscv_vcpu_host_fp_restore(struct kvm_cpu_context *cntx)
{
	if (riscv_isa_extension_available(NULL, d))
		__kvm_riscv_fp_d_restore(cntx);
	else if (riscv_isa_extension_available(NULL, f))
		__kvm_riscv_fp_f_restore(cntx);
}
#endif

int kvm_riscv_vcpu_get_reg_fp(struct kvm_vcpu *vcpu,
			      const struct kvm_one_reg *reg,
			      unsigned long rtype)
{
	struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
	unsigned long __user *uaddr =
			(unsigned long __user *)(unsigned long)reg->addr;
	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
					    KVM_REG_SIZE_MASK |
					    rtype);
	void *reg_val;

	if ((rtype == KVM_REG_RISCV_FP_F) &&
	    riscv_isa_extension_available(vcpu->arch.isa, f)) {
		if (KVM_REG_SIZE(reg->id) != sizeof(u32))
			return -EINVAL;
		if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr))
			reg_val = &cntx->fp.f.fcsr;
		else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) &&
			  reg_num <= KVM_REG_RISCV_FP_F_REG(f[31]))
			reg_val = &cntx->fp.f.f[reg_num];
		else
			return -ENOENT;
	} else if ((rtype == KVM_REG_RISCV_FP_D) &&
		   riscv_isa_extension_available(vcpu->arch.isa, d)) {
		if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) {
			if (KVM_REG_SIZE(reg->id) != sizeof(u32))
				return -EINVAL;
			reg_val = &cntx->fp.d.fcsr;
		} else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) &&
			   reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) {
			if (KVM_REG_SIZE(reg->id) != sizeof(u64))
				return -EINVAL;
			reg_val = &cntx->fp.d.f[reg_num];
		} else
			return -ENOENT;
	} else
		return -ENOENT;

	if (copy_to_user(uaddr, reg_val, KVM_REG_SIZE(reg->id)))
		return -EFAULT;

	return 0;
}

int kvm_riscv_vcpu_set_reg_fp(struct kvm_vcpu *vcpu,
			      const struct kvm_one_reg *reg,
			      unsigned long rtype)
{
	struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
	unsigned long __user *uaddr =
			(unsigned long __user *)(unsigned long)reg->addr;
	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
					    KVM_REG_SIZE_MASK |
					    rtype);
	void *reg_val;

	if ((rtype == KVM_REG_RISCV_FP_F) &&
	    riscv_isa_extension_available(vcpu->arch.isa, f)) {
		if (KVM_REG_SIZE(reg->id) != sizeof(u32))
			return -EINVAL;
		if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr))
			reg_val = &cntx->fp.f.fcsr;
		else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) &&
			  reg_num <= KVM_REG_RISCV_FP_F_REG(f[31]))
			reg_val = &cntx->fp.f.f[reg_num];
		else
			return -ENOENT;
	} else if ((rtype == KVM_REG_RISCV_FP_D) &&
		   riscv_isa_extension_available(vcpu->arch.isa, d)) {
		if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) {
			if (KVM_REG_SIZE(reg->id) != sizeof(u32))
				return -EINVAL;
			reg_val = &cntx->fp.d.fcsr;
		} else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) &&
			   reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) {
			if (KVM_REG_SIZE(reg->id) != sizeof(u64))
				return -EINVAL;
			reg_val = &cntx->fp.d.f[reg_num];
		} else
			return -ENOENT;
	} else
		return -ENOENT;

	if (copy_from_user(reg_val, uaddr, KVM_REG_SIZE(reg->id)))
		return -EFAULT;

	return 0;
}