[PATCH V3 07/11] LoongArch: KVM: Add EIOINTC user mode read and write functions

[Xianglai Li]

Implements the communication interface between the user mode
program and the kernel in EIOINTC interrupt control simulation,
which is used to obtain or send the simulation data of the
interrupt controller in the user mode process, and is used
in VM migration or VM saving and restoration.

Signed-off-by: Xianglai Li <lixianglai@xxxxxxxxxxx>
---
Cc: Bibo Mao <maobibo@xxxxxxxxxxx> 
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx> 
Cc: kvm@xxxxxxxxxxxxxxx 
Cc: loongarch@xxxxxxxxxxxxxxx 
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> 
Cc: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx> 
Cc: WANG Xuerui <kernel@xxxxxxxxxx> 
Cc: Xianglai li <lixianglai@xxxxxxxxxxx> 

 arch/loongarch/include/uapi/asm/kvm.h |  12 ++
 arch/loongarch/kvm/intc/eiointc.c     | 178 +++++++++++++++++++++++++-
 2 files changed, 188 insertions(+), 2 deletions(-)

diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
index ec9fe4cbf949..d019f88b6286 100644
--- a/arch/loongarch/include/uapi/asm/kvm.h
+++ b/arch/loongarch/include/uapi/asm/kvm.h
@@ -114,4 +114,16 @@ struct kvm_iocsr_entry {
 
 #define KVM_DEV_LOONGARCH_IPI_GRP_REGS			0x40000001
 
+#define KVM_DEV_LOONGARCH_EXTIOI_GRP_REGS		0x40000002
+
+#define KVM_DEV_LOONGARCH_EXTIOI_GRP_SW_STATUS		0x40000003
+#define KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_NUM_CPU	0x0
+#define KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_FEATURE	0x1
+#define KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_STATE	0x2
+
+#define KVM_DEV_LOONGARCH_EXTIOI_GRP_CTRL		0x40000004
+#define KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_NUM_CPU	0x0
+#define KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_FEATURE	0x1
+#define KVM_DEV_LOONGARCH_EXTIOI_CTRL_LOAD_FINISHED	0x3
+
 #endif /* __UAPI_ASM_LOONGARCH_KVM_H */
diff --git a/arch/loongarch/kvm/intc/eiointc.c b/arch/loongarch/kvm/intc/eiointc.c
index b372cd4264ef..118598d89d26 100644
--- a/arch/loongarch/kvm/intc/eiointc.c
+++ b/arch/loongarch/kvm/intc/eiointc.c
@@ -797,16 +797,190 @@ static const struct kvm_io_device_ops kvm_eiointc_virt_ops = {
 	.write	= kvm_eiointc_virt_write,
 };
 
+static int kvm_eiointc_ctrl_access(struct kvm_device *dev,
+					struct kvm_device_attr *attr)
+{
+	unsigned long  type = (unsigned long)attr->attr;
+	unsigned long flags;
+	struct loongarch_eiointc *s = dev->kvm->arch.eiointc;
+	void __user *data;
+	u32 i, start_irq;
+	int len, ret = 0;
+
+	data = (void __user *)attr->addr;
+	loongarch_ext_irq_lock(s, flags);
+	switch (type) {
+	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_NUM_CPU:
+		len = 4;
+		if (copy_from_user(&s->num_cpu, data, len))
+			ret = -EFAULT;
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_FEATURE:
+		len = 4;
+		if (copy_from_user(&s->features, data, len))
+			ret = -EFAULT;
+		if (!(s->features & BIT(EIOINTC_HAS_VIRT_EXTENSION)))
+			s->status |= BIT(EIOINTC_ENABLE);
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_LOAD_FINISHED:
+		eiointc_set_sw_coreisr(s);
+		for (i = 0; i < (EIOINTC_IRQS / 4); i++) {
+			start_irq = i * 4;
+			eiointc_update_sw_coremap(s, start_irq,
+					(void *)&s->coremap.reg_u32[i],
+					sizeof(u32), false);
+		}
+		break;
+	default:
+		break;
+	}
+	loongarch_ext_irq_unlock(s, flags);
+	return ret;
+}
+
+static int kvm_eiointc_regs_access(struct kvm_device *dev,
+					struct kvm_device_attr *attr,
+					bool is_write)
+{
+	int len, addr, cpuid, offset, ret = 0;
+	void __user *data;
+	void *p = NULL;
+	struct loongarch_eiointc *s;
+	unsigned long flags;
+
+	len = 4;
+	s = dev->kvm->arch.eiointc;
+	addr = attr->attr;
+	cpuid = addr >> 16;
+	addr &= 0xffff;
+	data = (void __user *)attr->addr;
+	switch (addr) {
+	case EIOINTC_NODETYPE_START ... EIOINTC_NODETYPE_END:
+		offset = (addr - EIOINTC_NODETYPE_START) / 4;
+		p = &s->nodetype.reg_u32[offset];
+		break;
+	case EIOINTC_IPMAP_START ... EIOINTC_IPMAP_END:
+		offset = (addr - EIOINTC_IPMAP_START) / 4;
+		p = &s->ipmap.reg_u32[offset];
+		break;
+	case EIOINTC_ENABLE_START ... EIOINTC_ENABLE_END:
+		offset = (addr - EIOINTC_ENABLE_START) / 4;
+		p = &s->enable.reg_u32[offset];
+		break;
+	case EIOINTC_BOUNCE_START ... EIOINTC_BOUNCE_END:
+		offset = (addr - EIOINTC_BOUNCE_START) / 4;
+		p = &s->bounce.reg_u32[offset];
+		break;
+	case EIOINTC_ISR_START ... EIOINTC_ISR_END:
+		offset = (addr - EIOINTC_ISR_START) / 4;
+		p = &s->isr.reg_u32[offset];
+		break;
+	case EIOINTC_COREISR_START ... EIOINTC_COREISR_END:
+		offset = (addr - EIOINTC_COREISR_START) / 4;
+		p = &s->coreisr.reg_u32[cpuid][offset];
+		break;
+	case EIOINTC_COREMAP_START ... EIOINTC_COREMAP_END:
+		offset = (addr - EIOINTC_COREMAP_START) / 4;
+		p = &s->coremap.reg_u32[offset];
+		break;
+	default:
+		kvm_err("%s: unknown eiointc register, addr = %d\n", __func__, addr);
+		return -EINVAL;
+	}
+
+	loongarch_ext_irq_lock(s, flags);
+	if (is_write) {
+		if (copy_from_user(p, data, len))
+			ret = -EFAULT;
+	} else {
+		if (copy_to_user(data, p, len))
+			ret = -EFAULT;
+	}
+	loongarch_ext_irq_unlock(s, flags);
+	return ret;
+}
+
+static int kvm_eiointc_sw_status_access(struct kvm_device *dev,
+					struct kvm_device_attr *attr,
+					bool is_write)
+{
+	int len, addr, ret = 0;
+	void __user *data;
+	void *p = NULL;
+	struct loongarch_eiointc *s;
+	unsigned long flags;
+
+	len = 4;
+	s = dev->kvm->arch.eiointc;
+	addr = attr->attr;
+	addr &= 0xffff;
+
+	data = (void __user *)attr->addr;
+	switch (addr) {
+	case KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_NUM_CPU:
+		p = &s->num_cpu;
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_FEATURE:
+		p = &s->features;
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_STATE:
+		p = &s->status;
+		break;
+	default:
+		kvm_err("%s: unknown eiointc register, addr = %d\n", __func__, addr);
+		return -EINVAL;
+	}
+	loongarch_ext_irq_lock(s, flags);
+	if (is_write) {
+		if (copy_from_user(p, data, len))
+			ret = -EFAULT;
+	} else {
+		if (copy_to_user(data, p, len))
+			ret = -EFAULT;
+	}
+	loongarch_ext_irq_unlock(s, flags);
+	return ret;
+}
+
 static int kvm_eiointc_get_attr(struct kvm_device *dev,
 				struct kvm_device_attr *attr)
 {
-	return 0;
+	__u32	group = attr->group;
+	int ret = -EINVAL;
+
+	switch (group) {
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_REGS:
+		ret = kvm_eiointc_regs_access(dev, attr, false);
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_SW_STATUS:
+		ret = kvm_eiointc_sw_status_access(dev, attr, false);
+		break;
+	default:
+		break;
+	}
+	return ret;
 }
 
 static int kvm_eiointc_set_attr(struct kvm_device *dev,
 				struct kvm_device_attr *attr)
 {
-	return 0;
+	__u32	group = attr->group;
+	int ret = -EINVAL;
+
+	switch (group) {
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_REGS:
+		ret = kvm_eiointc_regs_access(dev, attr, true);
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_SW_STATUS:
+		ret = kvm_eiointc_sw_status_access(dev, attr, true);
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_CTRL:
+		ret = kvm_eiointc_ctrl_access(dev, attr);
+		break;
+	default:
+		break;
+	}
+	return ret;
 }
 
 static void kvm_eiointc_destroy(struct kvm_device *dev)
-- 
2.39.1