KVM: s390: migration / injection of prog irq ilc
We have to migrate the program irq ilc and someday we will have to
specify the ilc without KVM trying to autodetect the value.
Let's reuse one of the spare fields in our program irq that should
always be set to 0 by user space. Because we also want to make use
of 0 ilcs ("not available"), we need a validity indicator.
If no valid ilc is given, we try to autodetect the ilc via the current
icptcode and icptstatus + parameter and store the valid ilc in the
irq structure.
This has a nice effect: QEMU's making use of KVM_S390_IRQ /
KVM_S390_SET_IRQ_STATE / KVM_S390_GET_IRQ_STATE for migration will
directly migrate the ilc without any changes.
Please note that we use bit 0 as validity and bit 1,2 for the ilc, so
by applying the ilc mask we directly get the ilen which is usually what
we work with.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index daa4fdb..e594a78 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -571,7 +571,7 @@
struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
struct kvm_s390_pgm_info pgm_info;
int rc = 0, nullifying = false;
- u16 ilen = kvm_s390_get_ilen(vcpu);
+ u16 ilen;
spin_lock(&li->lock);
pgm_info = li->irq.pgm;
@@ -579,6 +579,7 @@
memset(&li->irq.pgm, 0, sizeof(pgm_info));
spin_unlock(&li->lock);
+ ilen = pgm_info.flags & KVM_S390_PGM_FLAGS_ILC_MASK;
VCPU_EVENT(vcpu, 3, "deliver: program irq code 0x%x, ilen:%d",
pgm_info.code, ilen);
vcpu->stat.deliver_program_int++;
@@ -1043,8 +1044,16 @@
trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_PROGRAM_INT,
irq->u.pgm.code, 0);
+ if (!(irq->u.pgm.flags & KVM_S390_PGM_FLAGS_ILC_VALID)) {
+ /* auto detection if no valid ILC was given */
+ irq->u.pgm.flags &= ~KVM_S390_PGM_FLAGS_ILC_MASK;
+ irq->u.pgm.flags |= kvm_s390_get_ilen(vcpu);
+ irq->u.pgm.flags |= KVM_S390_PGM_FLAGS_ILC_VALID;
+ }
+
if (irq->u.pgm.code == PGM_PER) {
li->irq.pgm.code |= PGM_PER;
+ li->irq.pgm.flags = irq->u.pgm.flags;
/* only modify PER related information */
li->irq.pgm.per_address = irq->u.pgm.per_address;
li->irq.pgm.per_code = irq->u.pgm.per_code;
@@ -1053,6 +1062,7 @@
} else if (!(irq->u.pgm.code & PGM_PER)) {
li->irq.pgm.code = (li->irq.pgm.code & PGM_PER) |
irq->u.pgm.code;
+ li->irq.pgm.flags = irq->u.pgm.flags;
/* only modify non-PER information */
li->irq.pgm.trans_exc_code = irq->u.pgm.trans_exc_code;
li->irq.pgm.mon_code = irq->u.pgm.mon_code;