summaryrefslogtreecommitdiff
path: root/arch/s390/kvm/kvm-s390.c
diff options
context:
space:
mode:
authorDavid Hildenbrand <dahi@linux.vnet.ibm.com>2014-10-09 16:10:13 +0400
committerChristian Borntraeger <borntraeger@de.ibm.com>2015-01-23 15:25:37 +0300
commit2444b352c3acf54897b0e2803a7c4e66699f9f43 (patch)
tree42490c1860791c4d674fe8c40aaf77c4d0407ab7 /arch/s390/kvm/kvm-s390.c
parent9fbd80828cef1b1bba5a293609a021047bb86a7e (diff)
downloadlinux-2444b352c3acf54897b0e2803a7c4e66699f9f43.tar.xz
KVM: s390: forward most SIGP orders to user space
Most SIGP orders are handled partially in kernel and partially in user space. In order to: - Get a correct SIGP SET PREFIX handler that informs user space - Avoid race conditions between concurrently executed SIGP orders - Serialize SIGP orders per VCPU We need to handle all "slow" SIGP orders in user space. The remaining ones to be handled completely in kernel are: - SENSE - SENSE RUNNING - EXTERNAL CALL - EMERGENCY SIGNAL - CONDITIONAL EMERGENCY SIGNAL According to the PoP, they have to be fast. They can be executed without conflicting to the actions of other pending/concurrently executing orders (e.g. STOP vs. START). This patch introduces a new capability that will - when enabled - forward all but the mentioned SIGP orders to user space. The instruction counters in the kernel are still updated. Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390/kvm/kvm-s390.c')
-rw-r--r--arch/s390/kvm/kvm-s390.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index bfb2b990da9b..3677b8ca647f 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -166,6 +166,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
case KVM_CAP_S390_IRQCHIP:
case KVM_CAP_VM_ATTRIBUTES:
case KVM_CAP_MP_STATE:
+ case KVM_CAP_S390_USER_SIGP:
r = 1;
break;
case KVM_CAP_NR_VCPUS:
@@ -254,6 +255,10 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
kvm->arch.use_irqchip = 1;
r = 0;
break;
+ case KVM_CAP_S390_USER_SIGP:
+ kvm->arch.user_sigp = 1;
+ r = 0;
+ break;
default:
r = -EINVAL;
break;