#include <linux/bitmap.h>
#include <linux/sched/signal.h>
+#include <linux/string.h>
#include <asm/asm-offsets.h>
#include <asm/lowcore.h>
#include <asm/stp.h>
return 0;
}
+static void kvm_s390_sync_request_broadcast(struct kvm *kvm, int req)
+{
+ int cx;
+ struct kvm_vcpu *vcpu;
+
+ kvm_for_each_vcpu(cx, vcpu, kvm)
+ kvm_s390_sync_request(req, vcpu);
+}
+
+/*
+ * Must be called with kvm->srcu held to avoid races on memslots, and with
+ * kvm->lock to avoid races with ourselves and kvm_s390_vm_stop_migration.
+ */
+static int kvm_s390_vm_start_migration(struct kvm *kvm)
+{
+ struct kvm_s390_migration_state *mgs;
+ struct kvm_memory_slot *ms;
+ /* should be the only one */
+ struct kvm_memslots *slots;
+ unsigned long ram_pages;
+ int slotnr;
+
+ /* migration mode already enabled */
+ if (kvm->arch.migration_state)
+ return 0;
+
+ slots = kvm_memslots(kvm);
+ if (!slots || !slots->used_slots)
+ return -EINVAL;
+
+ mgs = kzalloc(sizeof(*mgs), GFP_KERNEL);
+ if (!mgs)
+ return -ENOMEM;
+ kvm->arch.migration_state = mgs;
+
+ if (kvm->arch.use_cmma) {
+ /*
+ * Get the last slot. They should be sorted by base_gfn, so the
+ * last slot is also the one at the end of the address space.
+ * We have verified above that at least one slot is present.
+ */
+ ms = slots->memslots + slots->used_slots - 1;
+ /* round up so we only use full longs */
+ ram_pages = roundup(ms->base_gfn + ms->npages, BITS_PER_LONG);
+ /* allocate enough bytes to store all the bits */
+ mgs->pgste_bitmap = vmalloc(ram_pages / 8);
+ if (!mgs->pgste_bitmap) {
+ kfree(mgs);
+ kvm->arch.migration_state = NULL;
+ return -ENOMEM;
+ }
+
+ mgs->bitmap_size = ram_pages;
+ atomic64_set(&mgs->dirty_pages, ram_pages);
+ /* mark all the pages in active slots as dirty */
+ for (slotnr = 0; slotnr < slots->used_slots; slotnr++) {
+ ms = slots->memslots + slotnr;
+ bitmap_set(mgs->pgste_bitmap, ms->base_gfn, ms->npages);
+ }
+
+ kvm_s390_sync_request_broadcast(kvm, KVM_REQ_START_MIGRATION);
+ }
+ return 0;
+}
+
+/*
+ * Must be called with kvm->lock to avoid races with ourselves and
+ * kvm_s390_vm_start_migration.
+ */
+static int kvm_s390_vm_stop_migration(struct kvm *kvm)
+{
+ struct kvm_s390_migration_state *mgs;
+
+ /* migration mode already disabled */
+ if (!kvm->arch.migration_state)
+ return 0;
+ mgs = kvm->arch.migration_state;
+ kvm->arch.migration_state = NULL;
+
+ if (kvm->arch.use_cmma) {
+ kvm_s390_sync_request_broadcast(kvm, KVM_REQ_STOP_MIGRATION);
+ vfree(mgs->pgste_bitmap);
+ }
+ kfree(mgs);
+ return 0;
+}
+
+static int kvm_s390_vm_set_migration(struct kvm *kvm,
+ struct kvm_device_attr *attr)
+{
+ int idx, res = -ENXIO;
+
+ mutex_lock(&kvm->lock);
+ switch (attr->attr) {
+ case KVM_S390_VM_MIGRATION_START:
+ idx = srcu_read_lock(&kvm->srcu);
+ res = kvm_s390_vm_start_migration(kvm);
+ srcu_read_unlock(&kvm->srcu, idx);
+ break;
+ case KVM_S390_VM_MIGRATION_STOP:
+ res = kvm_s390_vm_stop_migration(kvm);
+ break;
+ default:
+ break;
+ }
+ mutex_unlock(&kvm->lock);
+
+ return res;
+}
+
+static int kvm_s390_vm_get_migration(struct kvm *kvm,
+ struct kvm_device_attr *attr)
+{
+ u64 mig = (kvm->arch.migration_state != NULL);
+
+ if (attr->attr != KVM_S390_VM_MIGRATION_STATUS)
+ return -ENXIO;
+
+ if (copy_to_user((void __user *)attr->addr, &mig, sizeof(mig)))
+ return -EFAULT;
+ return 0;
+}
+
static int kvm_s390_set_tod_high(struct kvm *kvm, struct kvm_device_attr *attr)
{
u8 gtod_high;
case KVM_S390_VM_CRYPTO:
ret = kvm_s390_vm_set_crypto(kvm, attr);
break;
+ case KVM_S390_VM_MIGRATION:
+ ret = kvm_s390_vm_set_migration(kvm, attr);
+ break;
default:
ret = -ENXIO;
break;
case KVM_S390_VM_CPU_MODEL:
ret = kvm_s390_get_cpu_model(kvm, attr);
break;
+ case KVM_S390_VM_MIGRATION:
+ ret = kvm_s390_vm_get_migration(kvm, attr);
+ break;
default:
ret = -ENXIO;
break;
break;
}
break;
+ case KVM_S390_VM_MIGRATION:
+ ret = 0;
+ break;
default:
ret = -ENXIO;
break;
kvm_s390_destroy_adapters(kvm);
kvm_s390_clear_float_irqs(kvm);
kvm_s390_vsie_destroy(kvm);
+ if (kvm->arch.migration_state) {
+ vfree(kvm->arch.migration_state->pgste_bitmap);
+ kfree(kvm->arch.migration_state);
+ }
KVM_EVENT(3, "vm 0x%pK destroyed", kvm);
}
if (!vcpu->arch.sie_block->cbrlo)
return -ENOMEM;
- vcpu->arch.sie_block->ecb2 |= ECB2_CMMA;
vcpu->arch.sie_block->ecb2 &= ~ECB2_PFMFI;
return 0;
}
goto retry;
}
+ if (kvm_check_request(KVM_REQ_START_MIGRATION, vcpu)) {
+ /*
+ * Disable CMMA virtualization; we will emulate the ESSA
+ * instruction manually, in order to provide additional
+ * functionalities needed for live migration.
+ */
+ vcpu->arch.sie_block->ecb2 &= ~ECB2_CMMA;
+ goto retry;
+ }
+
+ if (kvm_check_request(KVM_REQ_STOP_MIGRATION, vcpu)) {
+ /*
+ * Re-enable CMMA virtualization if CMMA is available and
+ * was used.
+ */
+ if ((vcpu->kvm->arch.use_cmma) &&
+ (vcpu->kvm->mm->context.use_cmma))
+ vcpu->arch.sie_block->ecb2 |= ECB2_CMMA;
+ goto retry;
+ }
+
/* nothing to do, just clear the request */
kvm_clear_request(KVM_REQ_UNHALT, vcpu);
projects / karo-tx-linux.git / blobdiff