KVM: s390: include guest facilities in kvm facility test

Most facility related decisions in KVM have to take into account:

- the facilities offered by the underlying run container (LPAR/VM)
- the facilities supported by the KVM code itself
- the facilities requested by a guest VM

This patch adds the KVM driver requested facilities to the test routine.

It additionally renames struct s390_model_fac to kvm_s390_fac and its field
names to be more meaningful.

The semantics of the facilities stored in the KVM architecture structure
is changed. The address arch.model.fac->list now points to the guest
facility list and arch.model.fac->mask points to the KVM facility mask.

This patch fixes the behaviour of KVM for some facilities for guests
that ignore the guest visible facility bits, e.g. guests could use
transactional memory intructions on hosts supporting them even if the
chosen cpu model would not offer them.

The userspace interface is not affected by this change.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 16 insertions, 14 deletions

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 76894c8db4d7..5a02be4628f1 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -522,7 +522,7 @@ static int kvm_s390_set_processor(struct kvm *kvm, struct kvm_device_attr *attr)
 		memcpy(&kvm->arch.model.cpu_id, &proc->cpuid,
 		       sizeof(struct cpuid));
 		kvm->arch.model.ibc = proc->ibc;
-		memcpy(kvm->arch.model.fac->kvm, proc->fac_list,
+		memcpy(kvm->arch.model.fac->list, proc->fac_list,
 		       S390_ARCH_FAC_LIST_SIZE_BYTE);
 	} else
 		ret = -EFAULT;
@@ -556,7 +556,7 @@ static int kvm_s390_get_processor(struct kvm *kvm, struct kvm_device_attr *attr)
 	}
 	memcpy(&proc->cpuid, &kvm->arch.model.cpu_id, sizeof(struct cpuid));
 	proc->ibc = kvm->arch.model.ibc;
-	memcpy(&proc->fac_list, kvm->arch.model.fac->kvm, S390_ARCH_FAC_LIST_SIZE_BYTE);
+	memcpy(&proc->fac_list, kvm->arch.model.fac->list, S390_ARCH_FAC_LIST_SIZE_BYTE);
 	if (copy_to_user((void __user *)attr->addr, proc, sizeof(*proc)))
 		ret = -EFAULT;
 	kfree(proc);
@@ -576,8 +576,8 @@ static int kvm_s390_get_machine(struct kvm *kvm, struct kvm_device_attr *attr)
 	}
 	get_cpu_id((struct cpuid *) &mach->cpuid);
 	mach->ibc = sclp_get_ibc();
-	memcpy(&mach->fac_mask, kvm_s390_fac_list_mask,
-	       kvm_s390_fac_list_mask_size() * sizeof(u64));
+	memcpy(&mach->fac_mask, kvm->arch.model.fac->mask,
+	       S390_ARCH_FAC_LIST_SIZE_BYTE);
 	memcpy((unsigned long *)&mach->fac_list, S390_lowcore.stfle_fac_list,
 	       S390_ARCH_FAC_LIST_SIZE_BYTE);
 	if (copy_to_user((void __user *)attr->addr, mach, sizeof(*mach)))
@@ -893,16 +893,16 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	/*
 	 * The architectural maximum amount of facilities is 16 kbit. To store
 	 * this amount, 2 kbyte of memory is required. Thus we need a full
-	 * page to hold the active copy (arch.model.fac->sie) and the current
-	 * facilities set (arch.model.fac->kvm). Its address size has to be
+	 * page to hold the guest facility list (arch.model.fac->list) and the
+	 * facility mask (arch.model.fac->mask). Its address size has to be
 	 * 31 bits and word aligned.
 	 */
 	kvm->arch.model.fac =
-		(struct s390_model_fac *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+		(struct kvm_s390_fac *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 	if (!kvm->arch.model.fac)
 		goto out_nofac;
 
-	memcpy(kvm->arch.model.fac->kvm, S390_lowcore.stfle_fac_list,
+	memcpy(kvm->arch.model.fac->mask, S390_lowcore.stfle_fac_list,
 	       S390_ARCH_FAC_LIST_SIZE_BYTE);
 
 	/*
@@ -914,7 +914,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	 */
 	if (!MACHINE_IS_LPAR)
 		for (i = 0; i < kvm_s390_fac_list_mask_size(); i++)
-			kvm_s390_fac_list_mask[i] &= kvm->arch.model.fac->kvm[i];
+			kvm_s390_fac_list_mask[i] &= kvm->arch.model.fac->mask[i];
 
 	/*
 	 * Apply the kvm facility mask to limit the kvm supported/tolerated
@@ -922,11 +922,15 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	 */
 	for (i = 0; i < S390_ARCH_FAC_LIST_SIZE_U64; i++) {
 		if (i < kvm_s390_fac_list_mask_size())
-			kvm->arch.model.fac->kvm[i] &= kvm_s390_fac_list_mask[i];
+			kvm->arch.model.fac->mask[i] &= kvm_s390_fac_list_mask[i];
 		else
-			kvm->arch.model.fac->kvm[i] = 0UL;
+			kvm->arch.model.fac->mask[i] = 0UL;
 	}
 
+	/* Populate the facility list initially. */
+	memcpy(kvm->arch.model.fac->list, kvm->arch.model.fac->mask,
+	       S390_ARCH_FAC_LIST_SIZE_BYTE);
+
 	kvm_s390_get_cpu_id(&kvm->arch.model.cpu_id);
 	kvm->arch.model.ibc = sclp_get_ibc() & 0x0fff;
 
@@ -1172,8 +1176,6 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 
 	mutex_lock(&vcpu->kvm->lock);
 	vcpu->arch.cpu_id = vcpu->kvm->arch.model.cpu_id;
-	memcpy(vcpu->kvm->arch.model.fac->sie, vcpu->kvm->arch.model.fac->kvm,
-	       S390_ARCH_FAC_LIST_SIZE_BYTE);
 	vcpu->arch.sie_block->ibc = vcpu->kvm->arch.model.ibc;
 	mutex_unlock(&vcpu->kvm->lock);
 
@@ -1219,7 +1221,7 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
 		vcpu->arch.sie_block->scaol = (__u32)(__u64)kvm->arch.sca;
 		set_bit(63 - id, (unsigned long *) &kvm->arch.sca->mcn);
 	}
-	vcpu->arch.sie_block->fac = (int) (long) kvm->arch.model.fac->sie;
+	vcpu->arch.sie_block->fac = (int) (long) kvm->arch.model.fac->list;
 
 	spin_lock_init(&vcpu->arch.local_int.lock);
 	vcpu->arch.local_int.float_int = &kvm->arch.float_int;