KVM: s390: migrate vcpu interrupt state
This patch adds support to migrate vcpu interrupts. Two new vcpu ioctls
are added which get/set the complete status of pending interrupts in one
go. The ioctls are marked as available with the new capability
KVM_CAP_S390_IRQ_STATE.
We can not use a ONEREG, as the number of pending local interrupts is not
constant and depends on the number of CPUs.
To retrieve the interrupt state we add an ioctl KVM_S390_GET_IRQ_STATE.
Its input parameter is a pointer to a struct kvm_s390_irq_state which
has a buffer and length. For all currently pending interrupts, we copy
a struct kvm_s390_irq into the buffer and pass it to userspace.
To store interrupt state into a buffer provided by userspace, we add an
ioctl KVM_S390_SET_IRQ_STATE. It passes a struct kvm_s390_irq_state into
the kernel and injects all interrupts contained in the buffer.
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8bc25d4..3040b14 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -41,6 +41,9 @@
#include "trace-s390.h"
#define MEM_OP_MAX_SIZE 65536 /* Maximum transfer size for KVM_S390_MEM_OP */
+#define LOCAL_IRQS 32
+#define VCPU_IRQS_MAX_BUF (sizeof(struct kvm_s390_irq) * \
+ (KVM_MAX_VCPUS + LOCAL_IRQS))
#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU
@@ -181,6 +184,7 @@
case KVM_CAP_S390_USER_SIGP:
case KVM_CAP_S390_USER_STSI:
case KVM_CAP_S390_SKEYS:
+ case KVM_CAP_S390_IRQ_STATE:
r = 1;
break;
case KVM_CAP_S390_MEM_OP:
@@ -2500,6 +2504,38 @@
r = -EFAULT;
break;
}
+ case KVM_S390_SET_IRQ_STATE: {
+ struct kvm_s390_irq_state irq_state;
+
+ r = -EFAULT;
+ if (copy_from_user(&irq_state, argp, sizeof(irq_state)))
+ break;
+ if (irq_state.len > VCPU_IRQS_MAX_BUF ||
+ irq_state.len == 0 ||
+ irq_state.len % sizeof(struct kvm_s390_irq) > 0) {
+ r = -EINVAL;
+ break;
+ }
+ r = kvm_s390_set_irq_state(vcpu,
+ (void __user *) irq_state.buf,
+ irq_state.len);
+ break;
+ }
+ case KVM_S390_GET_IRQ_STATE: {
+ struct kvm_s390_irq_state irq_state;
+
+ r = -EFAULT;
+ if (copy_from_user(&irq_state, argp, sizeof(irq_state)))
+ break;
+ if (irq_state.len == 0) {
+ r = -EINVAL;
+ break;
+ }
+ r = kvm_s390_get_irq_state(vcpu,
+ (__u8 __user *) irq_state.buf,
+ irq_state.len);
+ break;
+ }
default:
r = -ENOTTY;
}