KVM: in-kernel IOAPIC save and restore support

This patch adds support for in-kernel ioapic save and restore (to
and from userspace). It uses the same get/set_irqchip ioctl as
in-kernel PIC.

Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

3 files changed, 39 insertions, 2 deletions

diff --git a/drivers/kvm/irq.h b/drivers/kvm/irq.h
index 4034f6576cd..30adddcb182 100644
--- a/drivers/kvm/irq.h
+++ b/drivers/kvm/irq.h
@@ -61,7 +61,7 @@ int kvm_cpu_get_interrupt(struct kvm_vcpu *v);
 int kvm_cpu_has_interrupt(struct kvm_vcpu *v);
 void kvm_pic_update_irq(struct kvm_pic *s);
 
-#define IOAPIC_NUM_PINS  24
+#define IOAPIC_NUM_PINS  KVM_IOAPIC_NUM_PINS
 #define IOAPIC_VERSION_ID 0x11  /* IOAPIC version */
 #define IOAPIC_EDGE_TRIG  0
 #define IOAPIC_LEVEL_TRIG 1
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index c270e4afd3f..61dff55f137 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -913,6 +913,11 @@ static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
                         &pic_irqchip(kvm)->pics[1],
                         sizeof(struct kvm_pic_state));
                 break;
+        case KVM_IRQCHIP_IOAPIC:
+                memcpy (&chip->chip.ioapic,
+                        ioapic_irqchip(kvm),
+                        sizeof(struct kvm_ioapic_state));
+                break;
         default:
                 r = -EINVAL;
                 break;
@@ -936,6 +941,11 @@ static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
                         &chip->chip.pic,
                         sizeof(struct kvm_pic_state));
                 break;
+        case KVM_IRQCHIP_IOAPIC:
+                memcpy (ioapic_irqchip(kvm),
+                        &chip->chip.ioapic,
+                        sizeof(struct kvm_ioapic_state));
+                break;
         default:
                 r = -EINVAL;
                 break;
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 6560f11870f..42d15150d7a 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -45,7 +45,7 @@ struct kvm_irq_level {
         __u32 level;
 };
 
-/* for KVM_GET_IRQCHIP / KVM_SET_IRQCHIP */
+/* for KVM_GET_IRQCHIP and KVM_SET_IRQCHIP */
 struct kvm_pic_state {
         __u8 last_irr;  /* edge detection */
         __u8 irr;               /* interrupt request register */
@@ -65,9 +65,35 @@ struct kvm_pic_state {
         __u8 elcr_mask;
 };
 
+#define KVM_IOAPIC_NUM_PINS  24
+struct kvm_ioapic_state {
+        __u64 base_address;
+        __u32 ioregsel;
+        __u32 id;
+        __u32 irr;
+        __u32 pad;
+        union {
+                __u64 bits;
+                struct {
+                        __u8 vector;
+                        __u8 delivery_mode:3;
+                        __u8 dest_mode:1;
+                        __u8 delivery_status:1;
+                        __u8 polarity:1;
+                        __u8 remote_irr:1;
+                        __u8 trig_mode:1;
+                        __u8 mask:1;
+                        __u8 reserve:7;
+                        __u8 reserved[4];
+                        __u8 dest_id;
+                } fields;
+        } redirtbl[KVM_IOAPIC_NUM_PINS];
+};
+
 enum kvm_irqchip_id {
         KVM_IRQCHIP_PIC_MASTER   = 0,
         KVM_IRQCHIP_PIC_SLAVE    = 1,
+        KVM_IRQCHIP_IOAPIC       = 2,
 };
 
 struct kvm_irqchip {
@@ -76,6 +102,7 @@ struct kvm_irqchip {
         union {
                 char dummy[512];  /* reserving space */
                 struct kvm_pic_state pic;
+                struct kvm_ioapic_state ioapic;
         } chip;
 };