KVM: Add get/set irqchip ioctls for in-kernel PIC live migration support

This patch adds two new ioctls to dump and write kernel irqchips for
save/restore and live migration. PIC s/r and l/m is implemented in this
patch.

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

diff --git a/drivers/kvm/i8259.c b/drivers/kvm/i8259.c
index ee6030dc5c04f3dff4034b49a4814319d479d2ce..a679157bc599ae0a54979ca9e75f9a4e6ff610dc 100644 (file)
--- a/drivers/kvm/i8259.c
+++ b/drivers/kvm/i8259.c
@@ -119,6 +119,11 @@ static void pic_update_irq(struct kvm_pic *s)
                s->irq_request(s->irq_request_opaque, 0);
 }
 
+void kvm_pic_update_irq(struct kvm_pic *s)
+{
+       pic_update_irq(s);
+}
+
 void kvm_pic_set_irq(void *opaque, int irq, int level)
 {
        struct kvm_pic *s = opaque;

diff --git a/drivers/kvm/irq.h b/drivers/kvm/irq.h
index 6ed856a41e231215e26175e31b812637ec588ddb..4034f6576cd930f12b40313da7b03823350b433b 100644 (file)
--- a/drivers/kvm/irq.h
+++ b/drivers/kvm/irq.h
@@ -59,6 +59,7 @@ void kvm_pic_set_irq(void *opaque, int irq, int level);
 int kvm_pic_read_irq(struct kvm_pic *s);
 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_VERSION_ID 0x11 /* IOAPIC version */

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 5063b3addbbf62a2a24caa355d7528ed01020db3..6e2c5f3f33fb2207ae8194c5cb266c3b9968e76f 100644 (file)
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -897,6 +897,53 @@ out:
        return r;
 }
 
+static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
+{
+       int r;
+
+       r = 0;
+       switch (chip->chip_id) {
+       case KVM_IRQCHIP_PIC_MASTER:
+               memcpy (&chip->chip.pic,
+                       &pic_irqchip(kvm)->pics[0],
+                       sizeof(struct kvm_pic_state));
+               break;
+       case KVM_IRQCHIP_PIC_SLAVE:
+               memcpy (&chip->chip.pic,
+                       &pic_irqchip(kvm)->pics[1],
+                       sizeof(struct kvm_pic_state));
+               break;
+       default:
+               r = -EINVAL;
+               break;
+       }
+       return r;
+}
+
+static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
+{
+       int r;
+
+       r = 0;
+       switch (chip->chip_id) {
+       case KVM_IRQCHIP_PIC_MASTER:
+               memcpy (&pic_irqchip(kvm)->pics[0],
+                       &chip->chip.pic,
+                       sizeof(struct kvm_pic_state));
+               break;
+       case KVM_IRQCHIP_PIC_SLAVE:
+               memcpy (&pic_irqchip(kvm)->pics[1],
+                       &chip->chip.pic,
+                       sizeof(struct kvm_pic_state));
+               break;
+       default:
+               r = -EINVAL;
+               break;
+       }
+       kvm_pic_update_irq(pic_irqchip(kvm));
+       return r;
+}
+
 static gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn)
 {
        int i;
@@ -2835,6 +2882,41 @@ static long kvm_vm_ioctl(struct file *filp,
                }
                break;
        }
+       case KVM_GET_IRQCHIP: {
+               /* 0: PIC master, 1: PIC slave, 2: IOAPIC */
+               struct kvm_irqchip chip;
+
+               r = -EFAULT;
+               if (copy_from_user(&chip, argp, sizeof chip))
+                       goto out;
+               r = -ENXIO;
+               if (!irqchip_in_kernel(kvm))
+                       goto out;
+               r = kvm_vm_ioctl_get_irqchip(kvm, &chip);
+               if (r)
+                       goto out;
+               r = -EFAULT;
+               if (copy_to_user(argp, &chip, sizeof chip))
+                       goto out;
+               r = 0;
+               break;
+       }
+       case KVM_SET_IRQCHIP: {
+               /* 0: PIC master, 1: PIC slave, 2: IOAPIC */
+               struct kvm_irqchip chip;
+
+               r = -EFAULT;
+               if (copy_from_user(&chip, argp, sizeof chip))
+                       goto out;
+               r = -ENXIO;
+               if (!irqchip_in_kernel(kvm))
+                       goto out;
+               r = kvm_vm_ioctl_set_irqchip(kvm, &chip);
+               if (r)
+                       goto out;
+               r = 0;
+               break;
+       }
        default:
                ;
        }

diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index b0a13d1b34cc8481b35e06dfa21a6ca4d0ab946f..6560f11870fd9982753e0fdf17556b7135769eb3 100644 (file)
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -45,6 +45,40 @@ struct kvm_irq_level {
        __u32 level;
 };
 
+/* for KVM_GET_IRQCHIP / KVM_SET_IRQCHIP */
+struct kvm_pic_state {
+       __u8 last_irr;  /* edge detection */
+       __u8 irr;               /* interrupt request register */
+       __u8 imr;               /* interrupt mask register */
+       __u8 isr;               /* interrupt service register */
+       __u8 priority_add;      /* highest irq priority */
+       __u8 irq_base;
+       __u8 read_reg_select;
+       __u8 poll;
+       __u8 special_mask;
+       __u8 init_state;
+       __u8 auto_eoi;
+       __u8 rotate_on_auto_eoi;
+       __u8 special_fully_nested_mode;
+       __u8 init4;             /* true if 4 byte init */
+       __u8 elcr;              /* PIIX edge/trigger selection */
+       __u8 elcr_mask;
+};
+
+enum kvm_irqchip_id {
+       KVM_IRQCHIP_PIC_MASTER   = 0,
+       KVM_IRQCHIP_PIC_SLAVE    = 1,
+};
+
+struct kvm_irqchip {
+       __u32 chip_id;
+       __u32 pad;
+        union {
+               char dummy[512];  /* reserving space */
+               struct kvm_pic_state pic;
+       } chip;
+};
+
 enum kvm_exit_reason {
        KVM_EXIT_UNKNOWN          = 0,
        KVM_EXIT_EXCEPTION        = 1,
@@ -299,6 +333,8 @@ struct kvm_signal_mask {
 /* Device model IOC */
 #define KVM_CREATE_IRQCHIP       _IO(KVMIO,  0x60)
 #define KVM_IRQ_LINE             _IOW(KVMIO, 0x61, struct kvm_irq_level)
+#define KVM_GET_IRQCHIP                  _IOWR(KVMIO, 0x62, struct kvm_irqchip)
+#define KVM_SET_IRQCHIP                  _IOR(KVMIO,  0x63, struct kvm_irqchip)
 
 /*
  * ioctls for vcpu fds