Commit f6deff35 authored by Tianrui Zhao's avatar Tianrui Zhao Committed by Huacai Chen
Browse files

LoongArch: KVM: Implement basic vcpu ioctl interfaces 



Implement basic vcpu ioctl interfaces, including:

1, vcpu KVM_ENABLE_CAP ioctl interface.

2, vcpu get registers and set registers operations, it is called when
user space use the ioctl interface to get or set regs.

Reviewed-by: default avatarBibo Mao <maobibo@loongson.cn>
Tested-by: default avatarHuacai Chen <chenhuacai@loongson.cn>
Signed-off-by: default avatarTianrui Zhao <zhaotianrui@loongson.cn>
Signed-off-by: default avatarHuacai Chen <chenhuacai@loongson.cn>
parent 2fc3bd86

arch/loongarch/kvm/vcpu.c

+261 −0
Original line number Diff line number Diff line
@@ -141,6 +141,267 @@ static int kvm_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu) 
	return RESUME_GUEST;

}



static int _kvm_getcsr(struct kvm_vcpu *vcpu, unsigned int id, u64 *val)

{

	unsigned long gintc;

	struct loongarch_csrs *csr = vcpu->arch.csr;



	if (get_gcsr_flag(id) & INVALID_GCSR)

		return -EINVAL;



	if (id == LOONGARCH_CSR_ESTAT) {

		/* ESTAT IP0~IP7 get from GINTC */

		gintc = kvm_read_sw_gcsr(csr, LOONGARCH_CSR_GINTC) & 0xff;

		*val = kvm_read_sw_gcsr(csr, LOONGARCH_CSR_ESTAT) | (gintc << 2);

		return 0;

	}



	/*

	 * Get software CSR state since software state is consistent

	 * with hardware for synchronous ioctl

	 */

	*val = kvm_read_sw_gcsr(csr, id);



	return 0;

}



static int _kvm_setcsr(struct kvm_vcpu *vcpu, unsigned int id, u64 val)

{

	int ret = 0, gintc;

	struct loongarch_csrs *csr = vcpu->arch.csr;



	if (get_gcsr_flag(id) & INVALID_GCSR)

		return -EINVAL;



	if (id == LOONGARCH_CSR_ESTAT) {

		/* ESTAT IP0~IP7 inject through GINTC */

		gintc = (val >> 2) & 0xff;

		kvm_set_sw_gcsr(csr, LOONGARCH_CSR_GINTC, gintc);



		gintc = val & ~(0xffUL << 2);

		kvm_set_sw_gcsr(csr, LOONGARCH_CSR_ESTAT, gintc);



		return ret;

	}



	kvm_write_sw_gcsr(csr, id, val);



	return ret;

}



static int kvm_get_one_reg(struct kvm_vcpu *vcpu,

		const struct kvm_one_reg *reg, u64 *v)

{

	int id, ret = 0;

	u64 type = reg->id & KVM_REG_LOONGARCH_MASK;



	switch (type) {

	case KVM_REG_LOONGARCH_CSR:

		id = KVM_GET_IOC_CSR_IDX(reg->id);

		ret = _kvm_getcsr(vcpu, id, v);

		break;

	case KVM_REG_LOONGARCH_CPUCFG:

		id = KVM_GET_IOC_CPUCFG_IDX(reg->id);

		if (id >= 0 && id < KVM_MAX_CPUCFG_REGS)

			*v = vcpu->arch.cpucfg[id];

		else

			ret = -EINVAL;

		break;

	case KVM_REG_LOONGARCH_KVM:

		switch (reg->id) {

		case KVM_REG_LOONGARCH_COUNTER:

			*v = drdtime() + vcpu->kvm->arch.time_offset;

			break;

		default:

			ret = -EINVAL;

			break;

		}

		break;

	default:

		ret = -EINVAL;

		break;

	}



	return ret;

}



static int kvm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)

{

	int ret = 0;

	u64 v, size = reg->id & KVM_REG_SIZE_MASK;



	switch (size) {

	case KVM_REG_SIZE_U64:

		ret = kvm_get_one_reg(vcpu, reg, &v);

		if (ret)

			return ret;

		ret = put_user(v, (u64 __user *)(long)reg->addr);

		break;

	default:

		ret = -EINVAL;

		break;

	}



	return ret;

}



static int kvm_set_one_reg(struct kvm_vcpu *vcpu,

			const struct kvm_one_reg *reg, u64 v)

{

	int id, ret = 0;

	u64 type = reg->id & KVM_REG_LOONGARCH_MASK;



	switch (type) {

	case KVM_REG_LOONGARCH_CSR:

		id = KVM_GET_IOC_CSR_IDX(reg->id);

		ret = _kvm_setcsr(vcpu, id, v);

		break;

	case KVM_REG_LOONGARCH_CPUCFG:

		id = KVM_GET_IOC_CPUCFG_IDX(reg->id);

		if (id >= 0 && id < KVM_MAX_CPUCFG_REGS)

			vcpu->arch.cpucfg[id] = (u32)v;

		else

			ret = -EINVAL;

		break;

	case KVM_REG_LOONGARCH_KVM:

		switch (reg->id) {

		case KVM_REG_LOONGARCH_COUNTER:

			/*

			 * gftoffset is relative with board, not vcpu

			 * only set for the first time for smp system

			 */

			if (vcpu->vcpu_id == 0)

				vcpu->kvm->arch.time_offset = (signed long)(v - drdtime());

			break;

		case KVM_REG_LOONGARCH_VCPU_RESET:

			kvm_reset_timer(vcpu);

			memset(&vcpu->arch.irq_pending, 0, sizeof(vcpu->arch.irq_pending));

			memset(&vcpu->arch.irq_clear, 0, sizeof(vcpu->arch.irq_clear));

			break;

		default:

			ret = -EINVAL;

			break;

		}

		break;

	default:

		ret = -EINVAL;

		break;

	}



	return ret;

}



static int kvm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)

{

	int ret = 0;

	u64 v, size = reg->id & KVM_REG_SIZE_MASK;



	switch (size) {

	case KVM_REG_SIZE_U64:

		ret = get_user(v, (u64 __user *)(long)reg->addr);

		if (ret)

			return ret;

		break;

	default:

		return -EINVAL;

	}



	return kvm_set_one_reg(vcpu, reg, v);

}



int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)

{

	return -ENOIOCTLCMD;

}



int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)

{

	return -ENOIOCTLCMD;

}



int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)

{

	int i;



	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)

		regs->gpr[i] = vcpu->arch.gprs[i];



	regs->pc = vcpu->arch.pc;



	return 0;

}



int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)

{

	int i;



	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)

		vcpu->arch.gprs[i] = regs->gpr[i];



	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */

	vcpu->arch.pc = regs->pc;



	return 0;

}



static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,

				     struct kvm_enable_cap *cap)

{

	/* FPU is enabled by default, will support LSX/LASX later. */

	return -EINVAL;

}



long kvm_arch_vcpu_ioctl(struct file *filp,

			 unsigned int ioctl, unsigned long arg)

{

	long r;

	void __user *argp = (void __user *)arg;

	struct kvm_vcpu *vcpu = filp->private_data;



	/*

	 * Only software CSR should be modified

	 *

	 * If any hardware CSR register is modified, vcpu_load/vcpu_put pair

	 * should be used. Since CSR registers owns by this vcpu, if switch

	 * to other vcpus, other vcpus need reload CSR registers.

	 *

	 * If software CSR is modified, bit KVM_LARCH_HWCSR_USABLE should

	 * be clear in vcpu->arch.aux_inuse, and vcpu_load will check

	 * aux_inuse flag and reload CSR registers form software.

	 */



	switch (ioctl) {

	case KVM_SET_ONE_REG:

	case KVM_GET_ONE_REG: {

		struct kvm_one_reg reg;



		r = -EFAULT;

		if (copy_from_user(&reg, argp, sizeof(reg)))

			break;

		if (ioctl == KVM_SET_ONE_REG) {

			r = kvm_set_reg(vcpu, &reg);

			vcpu->arch.aux_inuse &= ~KVM_LARCH_HWCSR_USABLE;

		} else

			r = kvm_get_reg(vcpu, &reg);

		break;

	}

	case KVM_ENABLE_CAP: {

		struct kvm_enable_cap cap;



		r = -EFAULT;

		if (copy_from_user(&cap, argp, sizeof(cap)))

			break;

		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);

		break;

	}

	default:

		r = -ENOIOCTLCMD;

		break;

	}



	return r;

}



int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)

{

	return 0;