arch/riscv/kvm/vcpu_fp.c

Source file repositories/reference/linux-study-clean/arch/riscv/kvm/vcpu_fp.c

File Facts

System
Linux kernel
Corpus path
arch/riscv/kvm/vcpu_fp.c
Extension
.c
Size
5138 bytes
Lines
176
Domain
Architecture Layer
Bucket
arch/riscv
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

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_num = array_index_nospec(reg_num,
					ARRAY_SIZE(cntx->fp.f.f));
			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_num = array_index_nospec(reg_num,
					ARRAY_SIZE(cntx->fp.d.f));
			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_num = array_index_nospec(reg_num,
					ARRAY_SIZE(cntx->fp.f.f));
			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_num = array_index_nospec(reg_num,
					ARRAY_SIZE(cntx->fp.d.f));
			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;
}

Annotation

Implementation Notes