KVM: s390: add functions to (un)register GISC with GISA

Add the Interruption Alert Mask (IAM) to the architecture specific
kvm struct. This mask in the GISA is used to define for which ISC
a GIB alert will 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.

Theses functions will be used by other adapter types like AP and PCI to
request pass-through interruption support.

Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190131085247.13826-12-mimu@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 7077762ab460..2cfff617cb21 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -781,6 +781,9 @@ struct kvm_s390_gisa {
 			u8  reserved03[11];
 			u32 airq_count;
 		} g1;
+		struct {
+			u64 word[4];
+		} u64;
 	};
 };
 
@@ -813,8 +816,15 @@ struct kvm_s390_vsie {
 	struct page *pages[KVM_MAX_VCPUS];
 };
 
+struct kvm_s390_gisa_iam {
+	u8 mask;
+	spinlock_t ref_lock;
+	u32 ref_count[MAX_ISC + 1];
+};
+
 struct kvm_s390_gisa_interrupt {
 	struct kvm_s390_gisa *origin;
+	struct kvm_s390_gisa_iam alert;
 };
 
 struct kvm_arch{
@@ -885,6 +895,9 @@ 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) {}