Re: [PATCH v12 12/31] LoongArch: KVM: Implement vcpu interrupt operations

[bibo, mao]

Reviewed-by: Bibo, Mao <maobibo@xxxxxxxxxxx>

在 2023/5/30 09:52, Tianrui Zhao 写道:
> Implement vcpu interrupt operations such as vcpu set irq and
> vcpu clear irq, using set_gcsr_estat to set irq which is
> parsed by the irq bitmap.
> 
> Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
> ---
>  arch/loongarch/kvm/interrupt.c | 127 +++++++++++++++++++++++++++++++++
>  arch/loongarch/kvm/vcpu.c      |  45 ++++++++++++
>  2 files changed, 172 insertions(+)
>  create mode 100644 arch/loongarch/kvm/interrupt.c
> 
> diff --git a/arch/loongarch/kvm/interrupt.c b/arch/loongarch/kvm/interrupt.c
> new file mode 100644
> index 000000000000..243bb19b387e
> --- /dev/null
> +++ b/arch/loongarch/kvm/interrupt.c
> @@ -0,0 +1,127 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
> + */
> +
> +#include <linux/errno.h>
> +#include <linux/err.h>
> +#include <asm/kvm_vcpu.h>
> +#include <asm/kvm_csr.h>
> +
> +static unsigned int int_to_coreint[EXCCODE_INT_NUM] = {
> +	[INT_TI]	= CPU_TIMER,
> +	[INT_IPI]	= CPU_IPI,
> +	[INT_SWI0]	= CPU_SIP0,
> +	[INT_SWI1]	= CPU_SIP1,
> +	[INT_HWI0]	= CPU_IP0,
> +	[INT_HWI1]	= CPU_IP1,
> +	[INT_HWI2]	= CPU_IP2,
> +	[INT_HWI3]	= CPU_IP3,
> +	[INT_HWI4]	= CPU_IP4,
> +	[INT_HWI5]	= CPU_IP5,
> +	[INT_HWI6]	= CPU_IP6,
> +	[INT_HWI7]	= CPU_IP7,
> +};
> +
> +static int _kvm_irq_deliver(struct kvm_vcpu *vcpu, unsigned int priority)
> +{
> +	unsigned int irq = 0;
> +
> +	clear_bit(priority, &vcpu->arch.irq_pending);
> +	if (priority < EXCCODE_INT_NUM)
> +		irq = int_to_coreint[priority];
> +
> +	switch (priority) {
> +	case INT_TI:
> +	case INT_IPI:
> +	case INT_SWI0:
> +	case INT_SWI1:
> +		set_gcsr_estat(irq);
> +		break;
> +
> +	case INT_HWI0:
> +	case INT_HWI1:
> +	case INT_HWI2:
> +	case INT_HWI3:
> +	case INT_HWI4:
> +	case INT_HWI5:
> +	case INT_HWI6:
> +	case INT_HWI7:
> +		set_csr_gintc(irq);
> +		break;
> +
> +	default:
> +		break;
> +	}
> +
> +	return 1;
> +}
> +
> +static int _kvm_irq_clear(struct kvm_vcpu *vcpu, unsigned int priority)
> +{
> +	unsigned int irq = 0;
> +
> +	clear_bit(priority, &vcpu->arch.irq_clear);
> +	if (priority < EXCCODE_INT_NUM)
> +		irq = int_to_coreint[priority];
> +
> +	switch (priority) {
> +	case INT_TI:
> +	case INT_IPI:
> +	case INT_SWI0:
> +	case INT_SWI1:
> +		clear_gcsr_estat(irq);
> +		break;
> +
> +	case INT_HWI0:
> +	case INT_HWI1:
> +	case INT_HWI2:
> +	case INT_HWI3:
> +	case INT_HWI4:
> +	case INT_HWI5:
> +	case INT_HWI6:
> +	case INT_HWI7:
> +		clear_csr_gintc(irq);
> +		break;
> +
> +	default:
> +		break;
> +	}
> +
> +	return 1;
> +}
> +
> +void _kvm_deliver_intr(struct kvm_vcpu *vcpu)
> +{
> +	unsigned long *pending = &vcpu->arch.irq_pending;
> +	unsigned long *pending_clr = &vcpu->arch.irq_clear;
> +	unsigned int priority;
> +
> +	if (!(*pending) && !(*pending_clr))
> +		return;
> +
> +	if (*pending_clr) {
> +		priority = __ffs(*pending_clr);
> +		while (priority <= INT_IPI) {
> +			_kvm_irq_clear(vcpu, priority);
> +			priority = find_next_bit(pending_clr,
> +					BITS_PER_BYTE * sizeof(*pending_clr),
> +					priority + 1);
> +		}
> +	}
> +
> +	if (*pending) {
> +		priority = __ffs(*pending);
> +		while (priority <= INT_IPI) {
> +			_kvm_irq_deliver(vcpu, priority);
> +			priority = find_next_bit(pending,
> +					BITS_PER_BYTE * sizeof(*pending),
> +					priority + 1);
> +		}
> +	}
> +}
> +
> +int _kvm_pending_timer(struct kvm_vcpu *vcpu)
> +{
> +	return test_bit(INT_TI, &vcpu->arch.irq_pending);
> +}
> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
> index 60213f7f7bac..f661743dbe66 100644
> --- a/arch/loongarch/kvm/vcpu.c
> +++ b/arch/loongarch/kvm/vcpu.c
> @@ -304,6 +304,51 @@ void kvm_lose_fpu(struct kvm_vcpu *vcpu)
>  	preempt_enable();
>  }
>  
> +int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
> +			     struct kvm_loongarch_interrupt *irq)
> +{
> +	int intr = (int)irq->irq;
> +	struct kvm_vcpu *dvcpu = NULL;
> +
> +	if (irq->cpu == -1)
> +		dvcpu = vcpu;
> +	else
> +		dvcpu = kvm_get_vcpu(vcpu->kvm, irq->cpu);
> +
> +	if (intr > 0)
> +		_kvm_queue_irq(dvcpu, intr);
> +	else if (intr < 0)
> +		_kvm_dequeue_irq(dvcpu, -intr);
> +	else {
> +		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
> +				irq->cpu, irq->irq);
> +		return -EINVAL;
> +	}
> +
> +	kvm_vcpu_kick(dvcpu);
> +	return 0;
> +}
> +
> +long kvm_arch_vcpu_async_ioctl(struct file *filp,
> +			       unsigned int ioctl, unsigned long arg)
> +{
> +	struct kvm_vcpu *vcpu = filp->private_data;
> +	void __user *argp = (void __user *)arg;
> +
> +	if (ioctl == KVM_INTERRUPT) {
> +		struct kvm_loongarch_interrupt irq;
> +
> +		if (copy_from_user(&irq, argp, sizeof(irq)))
> +			return -EFAULT;
> +		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
> +			  irq.irq);
> +
> +		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
> +	}
> +
> +	return -ENOIOCTLCMD;
> +}
> +
>  int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
>  {
>  	return 0;