[PATCH v6 7/7] arm/arm64: vgic-new: Implement KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO ioctl

[vijay.kilari@gmail.com (vijay.kilari at gmail.com)]

From: Vijaya Kumar K <Vijaya.Kumar@cavium.com>

Userspace requires to store and restore of line_level for
level triggered interrupts using ioctl KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
---
 arch/arm64/include/uapi/asm/kvm.h   |  6 +++++
 virt/kvm/arm/vgic/vgic-kvm-device.c | 50 ++++++++++++++++++++++++++++++++++++-
 virt/kvm/arm/vgic/vgic-mmio-v3.c    | 11 ++++++++
 virt/kvm/arm/vgic/vgic-mmio.c       | 33 ++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic-mmio.h       |  5 ++++
 virt/kvm/arm/vgic/vgic.h            |  3 +++
 6 files changed, 107 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 91c7137..4100f8c 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -211,6 +211,12 @@ struct kvm_arch_memory_slot {
 #define KVM_DEV_ARM_VGIC_GRP_CTRL	4
 #define KVM_DEV_ARM_VGIC_GRP_REDIST_REGS 5
 #define KVM_DEV_ARM_VGIC_CPU_SYSREGS    6
+#define KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO 7
+#define KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_SHIFT	10
+#define KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_MASK \
+			(0x3fffffULL << KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_SHIFT)
+#define KVM_DEV_ARM_VGIC_LINE_LEVEL_INTID_MASK	0x3ff
+#define VGIC_LEVEL_INFO_LINE_LEVEL	0
 
 #define   KVM_DEV_ARM_VGIC_CTRL_INIT	0
 
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index da532d1..0f82a91 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -512,6 +512,25 @@ static int vgic_v3_attr_regs_access(struct kvm_device *dev,
 						  regid, reg);
 		break;
 	}
+	case KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO: {
+		unsigned int info, intid;
+
+		info = (attr->attr & KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_MASK) >>
+			KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_SHIFT;
+		if (info == VGIC_LEVEL_INFO_LINE_LEVEL) {
+			if (is_write)
+				tmp32 = *reg;
+			intid = attr->attr &
+				KVM_DEV_ARM_VGIC_LINE_LEVEL_INTID_MASK;
+			ret = vgic_v3_line_level_info_uaccess(vcpu, is_write,
+							      intid, &tmp32);
+			if (!is_write)
+				*reg = tmp32;
+		} else {
+			ret = -EINVAL;
+		}
+		break;
+	}
 	default:
 		ret = -EINVAL;
 		break;
@@ -554,6 +573,17 @@ static int vgic_v3_set_attr(struct kvm_device *dev,
 
 		return vgic_v3_attr_regs_access(dev, attr, &reg, true);
 	}
+	case KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO: {
+		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+		u64 reg;
+		u32 tmp32;
+
+		if (get_user(tmp32, uaddr))
+			return -EFAULT;
+
+		reg = tmp32;
+		return vgic_v3_attr_regs_access(dev, attr, &reg, true);
+	}
 	}
 	return -ENXIO;
 }
@@ -589,8 +619,18 @@ static int vgic_v3_get_attr(struct kvm_device *dev,
 			return ret;
 		return put_user(reg, uaddr);
 	}
-	}
+	case KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO: {
+		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+		u64 reg;
+		u32 tmp32;
 
+		ret = vgic_v3_attr_regs_access(dev, attr, &reg, false);
+		if (ret)
+			return ret;
+		tmp32 = reg;
+		return put_user(tmp32, uaddr);
+	}
+	}
 	return -ENXIO;
 }
 
@@ -611,11 +651,19 @@ static int vgic_v3_has_attr(struct kvm_device *dev,
 		return vgic_v3_has_attr_regs(dev, attr);
 	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
 		return 0;
+	case KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO: {
+		if (((attr->attr & KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_MASK) >>
+		      KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_SHIFT) ==
+		      VGIC_LEVEL_INFO_LINE_LEVEL)
+			return 0;
+		break;
+	}
 	case KVM_DEV_ARM_VGIC_GRP_CTRL:
 		switch (attr->attr) {
 		case KVM_DEV_ARM_VGIC_CTRL_INIT:
 			return 0;
 		}
+		break;
 	}
 	return -ENXIO;
 }
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 8f46e61..648f588 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -807,3 +807,14 @@ int vgic_v3_redist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
 		return vgic_uaccess(vcpu, &rd_dev, is_write,
 				    offset, val);
 }
+
+int vgic_v3_line_level_info_uaccess(struct kvm_vcpu *vcpu, bool is_write,
+				    u32 intid, u32 *val)
+{
+	if (is_write)
+		vgic_write_irq_line_level_info(vcpu, intid, *val);
+	else
+		*val = vgic_read_irq_line_level_info(vcpu, intid);
+
+	return 0;
+}
diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c
index 173d6f0..fb018eb 100644
--- a/virt/kvm/arm/vgic/vgic-mmio.c
+++ b/virt/kvm/arm/vgic/vgic-mmio.c
@@ -371,6 +371,39 @@ void vgic_mmio_write_config(struct kvm_vcpu *vcpu,
 	}
 }
 
+unsigned long vgic_read_irq_line_level_info(struct kvm_vcpu *vcpu, u32 intid)
+{
+	int i;
+	unsigned long val = 0;
+
+	for (i = 0; i < 32; i++) {
+		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
+
+		if (irq->line_level)
+			val |= (1U << i);
+
+		vgic_put_irq(vcpu->kvm, irq);
+	}
+
+	return val;
+}
+
+void vgic_write_irq_line_level_info(struct kvm_vcpu *vcpu, u32 intid,
+				    const unsigned long val)
+{
+	int i;
+
+	for_each_set_bit(i, &val, 32) {
+		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
+
+		spin_lock(&irq->irq_lock);
+		irq->line_level = true;
+		spin_unlock(&irq->irq_lock);
+
+		vgic_put_irq(vcpu->kvm, irq);
+	}
+}
+
 static int match_region(const void *key, const void *elt)
 {
 	const unsigned int offset = (unsigned long)key;
diff --git a/virt/kvm/arm/vgic/vgic-mmio.h b/virt/kvm/arm/vgic/vgic-mmio.h
index acbf99e..938702c 100644
--- a/virt/kvm/arm/vgic/vgic-mmio.h
+++ b/virt/kvm/arm/vgic/vgic-mmio.h
@@ -181,6 +181,11 @@ int vgic_validate_mmio_region_addr(struct kvm_device *dev,
 				   const struct vgic_register_region *regions,
 				   int nr_regions, gpa_t addr);
 
+unsigned long vgic_read_irq_line_level_info(struct kvm_vcpu *vcpu, u32 intid);
+
+void vgic_write_irq_line_level_info(struct kvm_vcpu *vcpu, u32 intid,
+				    const unsigned long val);
+
 unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev);
 
 unsigned int vgic_v3_init_dist_iodev(struct vgic_io_device *dev);
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 0e632d0..77d3d84 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -130,6 +130,9 @@ int vgic_v3_cpu_sysregs_uaccess(struct kvm_vcpu *vcpu, bool is_write,
 			 u64 id, u64 *val);
 int vgic_v3_has_cpu_sysregs_attr(struct kvm_vcpu *vcpu, bool is_write, u64 id,
 				u64 *reg);
+int vgic_v3_line_level_info_uaccess(struct kvm_vcpu *vcpu, bool is_write,
+				    u32 intid, u32 *val);
+
 #else
 static inline int vgic_register_its_iodevs(struct kvm *kvm)
 {
-- 
1.9.1