diff options
Diffstat (limited to 'arch/s390/kvm/interrupt.c')
-rw-r--r-- | arch/s390/kvm/interrupt.c | 133 |
1 files changed, 106 insertions, 27 deletions
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 6a75352..62ec925 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -34,6 +34,106 @@ #define PFAULT_DONE 0x0680 #define VIRTIO_PARAM 0x0d00 +/* handle external calls via sigp interpretation facility */ +static int sca_ext_call_pending(struct kvm_vcpu *vcpu, int *src_id) +{ + int c, scn; + + if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_ECALL_PEND)) + return 0; + + read_lock(&vcpu->kvm->arch.sca_lock); + if (vcpu->kvm->arch.use_esca) { + struct esca_block *sca = vcpu->kvm->arch.sca; + union esca_sigp_ctrl sigp_ctrl = + sca->cpu[vcpu->vcpu_id].sigp_ctrl; + + c = sigp_ctrl.c; + scn = sigp_ctrl.scn; + } else { + struct bsca_block *sca = vcpu->kvm->arch.sca; + union bsca_sigp_ctrl sigp_ctrl = + sca->cpu[vcpu->vcpu_id].sigp_ctrl; + + c = sigp_ctrl.c; + scn = sigp_ctrl.scn; + } + read_unlock(&vcpu->kvm->arch.sca_lock); + + if (src_id) + *src_id = scn; + + return c; +} + +static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id) +{ + int expect, rc; + + read_lock(&vcpu->kvm->arch.sca_lock); + if (vcpu->kvm->arch.use_esca) { + struct esca_block *sca = vcpu->kvm->arch.sca; + union esca_sigp_ctrl *sigp_ctrl = + &(sca->cpu[vcpu->vcpu_id].sigp_ctrl); + union esca_sigp_ctrl new_val = {0}, old_val = *sigp_ctrl; + + new_val.scn = src_id; + new_val.c = 1; + old_val.c = 0; + + expect = old_val.value; + rc = cmpxchg(&sigp_ctrl->value, old_val.value, new_val.value); + } else { + struct bsca_block *sca = vcpu->kvm->arch.sca; + union bsca_sigp_ctrl *sigp_ctrl = + &(sca->cpu[vcpu->vcpu_id].sigp_ctrl); + union bsca_sigp_ctrl new_val = {0}, old_val = *sigp_ctrl; + + new_val.scn = src_id; + new_val.c = 1; + old_val.c = 0; + + expect = old_val.value; + rc = cmpxchg(&sigp_ctrl->value, old_val.value, new_val.value); + } + read_unlock(&vcpu->kvm->arch.sca_lock); + + if (rc != expect) { + /* another external call is pending */ + return -EBUSY; + } + atomic_or(CPUSTAT_ECALL_PEND, &vcpu->arch.sie_block->cpuflags); + return 0; +} + +static void sca_clear_ext_call(struct kvm_vcpu *vcpu) +{ + struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; + int rc, expect; + + atomic_andnot(CPUSTAT_ECALL_PEND, li->cpuflags); + read_lock(&vcpu->kvm->arch.sca_lock); + if (vcpu->kvm->arch.use_esca) { + struct esca_block *sca = vcpu->kvm->arch.sca; + union esca_sigp_ctrl *sigp_ctrl = + &(sca->cpu[vcpu->vcpu_id].sigp_ctrl); + union esca_sigp_ctrl old = *sigp_ctrl; + + expect = old.value; + rc = cmpxchg(&sigp_ctrl->value, old.value, 0); + } else { + struct bsca_block *sca = vcpu->kvm->arch.sca; + union bsca_sigp_ctrl *sigp_ctrl = + &(sca->cpu[vcpu->vcpu_id].sigp_ctrl); + union bsca_sigp_ctrl old = *sigp_ctrl; + + expect = old.value; + rc = cmpxchg(&sigp_ctrl->value, old.value, 0); + } + read_unlock(&vcpu->kvm->arch.sca_lock); + WARN_ON(rc != expect); /* cannot clear? */ +} + int psw_extint_disabled(struct kvm_vcpu *vcpu) { return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT); @@ -792,13 +892,11 @@ static const deliver_irq_t deliver_irq_funcs[] = { int kvm_s390_ext_call_pending(struct kvm_vcpu *vcpu) { struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; - uint8_t sigp_ctrl = vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sigp_ctrl; if (!sclp.has_sigpif) return test_bit(IRQ_PEND_EXT_EXTERNAL, &li->pending_irqs); - return (sigp_ctrl & SIGP_CTRL_C) && - (atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_ECALL_PEND); + return sca_ext_call_pending(vcpu, NULL); } int kvm_s390_vcpu_has_irq(struct kvm_vcpu *vcpu, int exclude_stop) @@ -909,9 +1007,7 @@ void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu) memset(&li->irq, 0, sizeof(li->irq)); spin_unlock(&li->lock); - /* clear pending external calls set by sigp interpretation facility */ - atomic_andnot(CPUSTAT_ECALL_PEND, li->cpuflags); - vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sigp_ctrl = 0; + sca_clear_ext_call(vcpu); } int __must_check kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu) @@ -1003,21 +1099,6 @@ static int __inject_pfault_init(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq) return 0; } -static int __inject_extcall_sigpif(struct kvm_vcpu *vcpu, uint16_t src_id) -{ - unsigned char new_val, old_val; - uint8_t *sigp_ctrl = &vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sigp_ctrl; - - new_val = SIGP_CTRL_C | (src_id & SIGP_CTRL_SCN_MASK); - old_val = *sigp_ctrl & ~SIGP_CTRL_C; - if (cmpxchg(sigp_ctrl, old_val, new_val) != old_val) { - /* another external call is pending */ - return -EBUSY; - } - atomic_or(CPUSTAT_ECALL_PEND, &vcpu->arch.sie_block->cpuflags); - return 0; -} - static int __inject_extcall(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq) { struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; @@ -1034,7 +1115,7 @@ static int __inject_extcall(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq) return -EINVAL; if (sclp.has_sigpif) - return __inject_extcall_sigpif(vcpu, src_id); + return sca_inject_ext_call(vcpu, src_id); if (test_and_set_bit(IRQ_PEND_EXT_EXTERNAL, &li->pending_irqs)) return -EBUSY; @@ -2203,7 +2284,7 @@ static void store_local_irq(struct kvm_s390_local_interrupt *li, int kvm_s390_get_irq_state(struct kvm_vcpu *vcpu, __u8 __user *buf, int len) { - uint8_t sigp_ctrl = vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sigp_ctrl; + int scn; unsigned long sigp_emerg_pending[BITS_TO_LONGS(KVM_MAX_VCPUS)]; struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; unsigned long pending_irqs; @@ -2243,14 +2324,12 @@ int kvm_s390_get_irq_state(struct kvm_vcpu *vcpu, __u8 __user *buf, int len) } } - if ((sigp_ctrl & SIGP_CTRL_C) && - (atomic_read(&vcpu->arch.sie_block->cpuflags) & - CPUSTAT_ECALL_PEND)) { + if (sca_ext_call_pending(vcpu, &scn)) { if (n + sizeof(irq) > len) return -ENOBUFS; memset(&irq, 0, sizeof(irq)); irq.type = KVM_S390_INT_EXTERNAL_CALL; - irq.u.extcall.code = sigp_ctrl & SIGP_CTRL_SCN_MASK; + irq.u.extcall.code = scn; if (copy_to_user(&buf[n], &irq, sizeof(irq))) return -EFAULT; n += sizeof(irq); |