Add the IAM (Interruption Alert Mask) to the architectue specific
kvm struct. This mask in the GISA is used to define for which ISC
a GIB alert can be issued.
The functions kvm_s390_gisc_register() and kvm_s390_gisc_unregister()
are used to (un)register a GISC (guest ISC) with a virtual machine and
its GISA.
Upon successful completion, kvm_s390_gisc_register() returns the
ISC to be used for GIB alert interruptions. A negative return code
indicates an error during registration.
Signed-off-by: Michael Mueller <mimu@xxxxxxxxxxxxx>
---
arch/s390/include/asm/kvm_host.h | 6 ++++++
arch/s390/kvm/interrupt.c | 44 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 50 insertions(+)
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 3e3225ea303b..3b7902a8573d 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -850,6 +850,9 @@ struct kvm_arch{
struct kvm_s390_gisa *gisa;
int gib_in_use;
atomic_t vcpus_in_sie;
+ u8 iam;
+ u32 iam_ref_count[MAX_ISC + 1];
+ spinlock_t iam_ref_lock;
};
#define KVM_HVA_ERR_BAD (-1UL)
@@ -883,6 +886,9 @@ void kvm_arch_crypto_set_masks(struct kvm *kvm, unsigned long *apm,
extern int sie64a(struct kvm_s390_sie_block *, u64 *);
extern char sie_exit;
+extern int kvm_s390_gisc_register(struct kvm *kvm, u32 gisc);
+extern int kvm_s390_gisc_unregister(struct kvm *kvm, u32 gisc);
+
static inline void kvm_arch_hardware_disable(void) {}
static inline void kvm_arch_check_processor_compat(void *rtn) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 37a5df4e8dac..dd80bdc056a5 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -2962,6 +2962,8 @@ void kvm_s390_gisa_init(struct kvm *kvm)
{
if (css_general_characteristics.aiv) {
kvm->arch.gisa = &kvm->arch.sie_page2->gisa;
+ kvm->arch.iam = 0;
+ spin_lock_init(&kvm->arch.iam_ref_lock);
VM_EVENT(kvm, 3, "gisa 0x%pK initialized", kvm->arch.gisa);
kvm_s390_gisa_clear(kvm);
kvm->arch.gib_in_use = !!gib;
@@ -2973,8 +2975,50 @@ void kvm_s390_gisa_destroy(struct kvm *kvm)
if (!kvm->arch.gisa)
return;
kvm->arch.gisa = NULL;
+ kvm->arch.iam = 0;
}
+int kvm_s390_gisc_register(struct kvm *kvm, u32 gisc)
+{
+ if (!kvm->arch.gib_in_use)
+ return -ENODEV;
+ if (gisc > MAX_ISC)
+ return -EINVAL;
+
+ spin_lock(&kvm->arch.iam_ref_lock);
+ if (kvm->arch.iam_ref_count[gisc] == 0)
+ kvm->arch.iam |= 0x80 >> gisc;
+ kvm->arch.iam_ref_count[gisc]++;
+ spin_unlock(&kvm->arch.iam_ref_lock);
+
+ return gib->nisc;
+}
+EXPORT_SYMBOL_GPL(kvm_s390_gisc_register);
+
+int kvm_s390_gisc_unregister(struct kvm *kvm, u32 gisc)
+{
+ int rc = 0;
+
+ if (!kvm->arch.gib_in_use)
+ return -ENODEV;
+ if (gisc > MAX_ISC)
+ return -EINVAL;
+
+ spin_lock(&kvm->arch.iam_ref_lock);
+ if (kvm->arch.iam_ref_count[gisc] == 0) {
+ rc = -EFAULT;
+ goto out;
+ }
+ kvm->arch.iam_ref_count[gisc]--;
+ if (kvm->arch.iam_ref_count[gisc] == 0)
+ kvm->arch.iam &= ~(0x80 >> gisc);
+out:
+ spin_unlock(&kvm->arch.iam_ref_lock);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(kvm_s390_gisc_unregister);
+
void kvm_s390_gib_destroy(void)
{
if (!gib)
--
2.13.4
