[PATCH] add ioctl's to save/restore mpstate

[PATCH] add ioctl's to save/restore mpstate

[Marcelo Tosatti]

So userspace can save/restore the mpstate during migration.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>


diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index cb57b6a..2ce22d6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -814,6 +814,7 @@ int kvm_dev_ioctl_check_extension(long ext)
 	case KVM_CAP_CLOCKSOURCE:
 	case KVM_CAP_PIT:
 	case KVM_CAP_NOP_IO_DELAY:
+	case KVM_CAP_MP_STATE:
 		r = 1;
 		break;
 	case KVM_CAP_VAPIC:
@@ -3057,6 +3058,24 @@ int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 	return 0;
 }
 
+int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
+				    int *mp_state)
+{
+	vcpu_load(vcpu);
+	*mp_state = vcpu->arch.mp_state;
+	vcpu_put(vcpu);
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
+				    int *mp_state)
+{
+	vcpu_load(vcpu);
+	vcpu->arch.mp_state = *mp_state;
+	vcpu_put(vcpu);
+	return 0;
+}
+
 static void set_segment(struct kvm_vcpu *vcpu,
 			struct kvm_segment *var, int seg)
 {
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 37b963e..23f65ba 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -279,6 +279,7 @@ struct kvm_s390_interrupt {
 #define KVM_CAP_PIT 11
 #define KVM_CAP_NOP_IO_DELAY 12
 #define KVM_CAP_PV_MMU 13
+#define KVM_CAP_MP_STATE 14
 
 /*
  * ioctls for VM fds
@@ -340,5 +341,7 @@ struct kvm_s390_interrupt {
 #define KVM_S390_SET_INITIAL_PSW  _IOW(KVMIO,  0x96, struct kvm_s390_psw)
 /* initial reset for s390 */
 #define KVM_S390_INITIAL_RESET    _IO(KVMIO,  0x97)
+#define KVM_GET_MP_STATE	  _IO(KVMIO,  0x98)
+#define KVM_SET_MP_STATE	  _IO(KVMIO,  0x99)
 
 #endif
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index a2ceb51..9ced073 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -224,6 +224,10 @@ int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 				  struct kvm_sregs *sregs);
 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 				  struct kvm_sregs *sregs);
+int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
+				    int *mp_state);
+int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
+				    int *mp_state);
 int kvm_arch_vcpu_ioctl_debug_guest(struct kvm_vcpu *vcpu,
 				    struct kvm_debug_guest *dbg);
 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 3396a5f..95001da 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -924,6 +924,30 @@ out_free2:
 		r = 0;
 		break;
 	}
+	case KVM_GET_MP_STATE: {
+		int mp_state;
+
+		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
+		if (r)
+			goto out;
+		r = -EFAULT;
+		if (copy_to_user(argp, &mp_state, sizeof (int)))
+			goto out;
+		r = 0;
+		break;
+	}
+	case KVM_SET_MP_STATE: {
+		int mp_state;
+
+		r = -EFAULT;
+		if (copy_from_user(&mp_state, argp, sizeof (int)))
+			goto out;
+		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
+		if (r)
+			goto out;
+		r = 0;
+		break;
+	}
 	case KVM_TRANSLATE: {
 		struct kvm_translation tr;
 

-------------------------------------------------------------------------
This SF.net email is sponsored by the 2008 JavaOne(SM) Conference 
Register now and save $200. Hurry, offer ends at 11:59 p.m., 
Monday, April 7! Use priority code J8TLD2. 
http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone

Re: [PATCH] add ioctl's to save/restore mpstate

[Avi Kivity]

Marcelo Tosatti wrote:
>  /*
>   * ioctls for VM fds
> @@ -340,5 +341,7 @@ struct kvm_s390_interrupt {
>  #define KVM_S390_SET_INITIAL_PSW  _IOW(KVMIO,  0x96, struct kvm_s390_psw)
>  /* initial reset for s390 */
>  #define KVM_S390_INITIAL_RESET    _IO(KVMIO,  0x97)
> +#define KVM_GET_MP_STATE	  _IO(KVMIO,  0x98)
> +#define KVM_SET_MP_STATE	  _IO(KVMIO,  0x99)
>   

This needs _IOW or _IORW to document transfer direction and structure 
size.  Please put the data in a structure, and document the values by 
moving the #defines into linux/kvm.h

-- 
Any sufficiently difficult bug is indistinguishable from a feature.


-------------------------------------------------------------------------
This SF.net email is sponsored by the 2008 JavaOne(SM) Conference 
Don't miss this year's exciting event. There's still time to save $100. 
Use priority code J8TL2D2. 
http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone