Merge branch 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / arch / s390 / kvm / kvm-s390.c

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 2f3e14f..339b34a 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -166,7 +166,9 @@ int kvm_dev_ioctl_check_extension(long ext)
        case KVM_CAP_IOEVENTFD:
        case KVM_CAP_DEVICE_CTRL:
        case KVM_CAP_ENABLE_CAP_VM:
+       case KVM_CAP_S390_IRQCHIP:
        case KVM_CAP_VM_ATTRIBUTES:
+       case KVM_CAP_MP_STATE:
                r = 1;
                break;
        case KVM_CAP_NR_VCPUS:
@@ -595,7 +597,8 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu)
        vcpu->arch.sie_block->pp = 0;
        vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
        kvm_clear_async_pf_completion_queue(vcpu);
-       kvm_s390_vcpu_stop(vcpu);
+       if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
+               kvm_s390_vcpu_stop(vcpu);
        kvm_s390_clear_local_irqs(vcpu);
 }
 
@@ -647,8 +650,6 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
                        return rc;
        }
        hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
-       tasklet_init(&vcpu->arch.tasklet, kvm_s390_tasklet,
-                    (unsigned long) vcpu);
        vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;
        get_cpu_id(&vcpu->arch.cpu_id);
        vcpu->arch.cpu_id.version = 0xff;
@@ -926,7 +927,7 @@ static int kvm_arch_vcpu_ioctl_set_initial_psw(struct kvm_vcpu *vcpu, psw_t psw)
 {
        int rc = 0;
 
-       if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED))
+       if (!is_vcpu_stopped(vcpu))
                rc = -EBUSY;
        else {
                vcpu->run->psw_mask = psw.mask;
@@ -980,13 +981,34 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
                                    struct kvm_mp_state *mp_state)
 {
-       return -EINVAL; /* not implemented yet */
+       /* CHECK_STOP and LOAD are not supported yet */
+       return is_vcpu_stopped(vcpu) ? KVM_MP_STATE_STOPPED :
+                                      KVM_MP_STATE_OPERATING;
 }
 
 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
                                    struct kvm_mp_state *mp_state)
 {
-       return -EINVAL; /* not implemented yet */
+       int rc = 0;
+
+       /* user space knows about this interface - let it control the state */
+       vcpu->kvm->arch.user_cpu_state_ctrl = 1;
+
+       switch (mp_state->mp_state) {
+       case KVM_MP_STATE_STOPPED:
+               kvm_s390_vcpu_stop(vcpu);
+               break;
+       case KVM_MP_STATE_OPERATING:
+               kvm_s390_vcpu_start(vcpu);
+               break;
+       case KVM_MP_STATE_LOAD:
+       case KVM_MP_STATE_CHECK_STOP:
+               /* fall through - CHECK_STOP and LOAD are not supported yet */
+       default:
+               rc = -ENXIO;
+       }
+
+       return rc;
 }
 
 bool kvm_s390_cmma_enabled(struct kvm *kvm)
@@ -1045,6 +1067,9 @@ retry:
                goto retry;
        }
 
+       /* nothing to do, just clear the request */
+       clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+
        return 0;
 }
 
@@ -1284,7 +1309,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
        if (vcpu->sigset_active)
                sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 
-       kvm_s390_vcpu_start(vcpu);
+       if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) {
+               kvm_s390_vcpu_start(vcpu);
+       } else if (is_vcpu_stopped(vcpu)) {
+               pr_err_ratelimited("kvm-s390: can't run stopped vcpu %d\n",
+                                  vcpu->vcpu_id);
+               return -EINVAL;
+       }
 
        switch (kvm_run->exit_reason) {
        case KVM_EXIT_S390_SIEIC:
@@ -1413,11 +1444,6 @@ int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr)
        return kvm_s390_store_status_unloaded(vcpu, addr);
 }
 
-static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu)
-{
-       return atomic_read(&(vcpu)->arch.sie_block->cpuflags) & CPUSTAT_STOPPED;
-}
-
 static void __disable_ibs_on_vcpu(struct kvm_vcpu *vcpu)
 {
        kvm_check_request(KVM_REQ_ENABLE_IBS, vcpu);
@@ -1451,7 +1477,7 @@ void kvm_s390_vcpu_start(struct kvm_vcpu *vcpu)
 
        trace_kvm_s390_vcpu_start_stop(vcpu->vcpu_id, 1);
        /* Only one cpu at a time may enter/leave the STOPPED state. */
-       spin_lock_bh(&vcpu->kvm->arch.start_stop_lock);
+       spin_lock(&vcpu->kvm->arch.start_stop_lock);
        online_vcpus = atomic_read(&vcpu->kvm->online_vcpus);
 
        for (i = 0; i < online_vcpus; i++) {
@@ -1477,7 +1503,7 @@ void kvm_s390_vcpu_start(struct kvm_vcpu *vcpu)
         * Let's play safe and flush the VCPU at startup.
         */
        vcpu->arch.sie_block->ihcpu  = 0xffff;
-       spin_unlock_bh(&vcpu->kvm->arch.start_stop_lock);
+       spin_unlock(&vcpu->kvm->arch.start_stop_lock);
        return;
 }
 
@@ -1491,10 +1517,18 @@ void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu)
 
        trace_kvm_s390_vcpu_start_stop(vcpu->vcpu_id, 0);
        /* Only one cpu at a time may enter/leave the STOPPED state. */
-       spin_lock_bh(&vcpu->kvm->arch.start_stop_lock);
+       spin_lock(&vcpu->kvm->arch.start_stop_lock);
        online_vcpus = atomic_read(&vcpu->kvm->online_vcpus);
 
+       /* Need to lock access to action_bits to avoid a SIGP race condition */
+       spin_lock(&vcpu->arch.local_int.lock);
        atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
+
+       /* SIGP STOP and SIGP STOP AND STORE STATUS has been fully processed */
+       vcpu->arch.local_int.action_bits &=
+                                ~(ACTION_STOP_ON_STOP | ACTION_STORE_ON_STOP);
+       spin_unlock(&vcpu->arch.local_int.lock);
+
        __disable_ibs_on_vcpu(vcpu);
 
        for (i = 0; i < online_vcpus; i++) {
@@ -1512,7 +1546,7 @@ void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu)
                __enable_ibs_on_vcpu(started_vcpu);
        }
 
-       spin_unlock_bh(&vcpu->kvm->arch.start_stop_lock);
+       spin_unlock(&vcpu->kvm->arch.start_stop_lock);
        return;
 }