Merge tag 'kvm-s390-next-5.18-2' of https://git.kernel.org/pub/scm/li…

…nux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fix, test and feature for 5.18 part 2

- memop selftest
- fix SCK locking
- adapter interruptions virtualization for secure guests

arch/s390/include/asm/uv.h

@@ -80,6 +80,7 @@ enum uv_cmds_inst {
 
 enum uv_feat_ind {
 	BIT_UV_FEAT_MISC = 0,
+	BIT_UV_FEAT_AIV = 1,
 };
 
 struct uv_cb_header {

arch/s390/kvm/interrupt.c

@@ -1901,13 +1901,12 @@ static int __inject_io(struct kvm *kvm, struct kvm_s390_interrupt_info *inti)
 	isc = int_word_to_isc(inti->io.io_int_word);
 
 	/*
-	 * Do not make use of gisa in protected mode. We do not use the lock
-	 * checking variant as this is just a performance optimization and we
-	 * do not hold the lock here. This is ok as the code will pick
-	 * interrupts from both "lists" for delivery.
+	 * We do not use the lock checking variant as this is just a
+	 * performance optimization and we do not hold the lock here.
+	 * This is ok as the code will pick interrupts from both "lists"
+	 * for delivery.
 	 */
-	if (!kvm_s390_pv_get_handle(kvm) &&
-	    gi->origin && inti->type & KVM_S390_INT_IO_AI_MASK) {
+	if (gi->origin && inti->type & KVM_S390_INT_IO_AI_MASK) {
 		VM_EVENT(kvm, 4, "%s isc %1u", "inject: I/O (AI/gisa)", isc);
 		gisa_set_ipm_gisc(gi->origin, isc);
 		kfree(inti);
@@ -3171,9 +3170,33 @@ void kvm_s390_gisa_init(struct kvm *kvm)
 	VM_EVENT(kvm, 3, "gisa 0x%pK initialized", gi->origin);
 }
 
+void kvm_s390_gisa_enable(struct kvm *kvm)
+{
+	struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
+	struct kvm_vcpu *vcpu;
+	unsigned long i;
+	u32 gisa_desc;
+
+	if (gi->origin)
+		return;
+	kvm_s390_gisa_init(kvm);
+	gisa_desc = kvm_s390_get_gisa_desc(kvm);
+	if (!gisa_desc)
+		return;
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		mutex_lock(&vcpu->mutex);
+		vcpu->arch.sie_block->gd = gisa_desc;
+		vcpu->arch.sie_block->eca |= ECA_AIV;
+		VCPU_EVENT(vcpu, 3, "AIV gisa format-%u enabled for cpu %03u",
+			   vcpu->arch.sie_block->gd & 0x3, vcpu->vcpu_id);
+		mutex_unlock(&vcpu->mutex);
+	}
+}
+
 void kvm_s390_gisa_destroy(struct kvm *kvm)
 {
 	struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
+	struct kvm_s390_gisa *gisa = gi->origin;
 
 	if (!gi->origin)
 		return;
@@ -3184,6 +3207,25 @@ void kvm_s390_gisa_destroy(struct kvm *kvm)
 		cpu_relax();
 	hrtimer_cancel(&gi->timer);
 	gi->origin = NULL;
+	VM_EVENT(kvm, 3, "gisa 0x%pK destroyed", gisa);
+}
+
+void kvm_s390_gisa_disable(struct kvm *kvm)
+{
+	struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
+	struct kvm_vcpu *vcpu;
+	unsigned long i;
+
+	if (!gi->origin)
+		return;
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		mutex_lock(&vcpu->mutex);
+		vcpu->arch.sie_block->eca &= ~ECA_AIV;
+		vcpu->arch.sie_block->gd = 0U;
+		mutex_unlock(&vcpu->mutex);
+		VCPU_EVENT(vcpu, 3, "AIV disabled for cpu %03u", vcpu->vcpu_id);
+	}
+	kvm_s390_gisa_destroy(kvm);
 }
 
 /**

arch/s390/kvm/kvm-s390.c

@@ -2195,6 +2195,9 @@ static int kvm_s390_cpus_from_pv(struct kvm *kvm, u16 *rcp, u16 *rrcp)
 		}
 		mutex_unlock(&vcpu->mutex);
 	}
+	/* Ensure that we re-enable gisa if the non-PV guest used it but the PV guest did not. */
+	if (use_gisa)
+		kvm_s390_gisa_enable(kvm);
 	return ret;
 }
 
@@ -2206,6 +2209,10 @@ static int kvm_s390_cpus_to_pv(struct kvm *kvm, u16 *rc, u16 *rrc)
 
 	struct kvm_vcpu *vcpu;
 
+	/* Disable the GISA if the ultravisor does not support AIV. */
+	if (!test_bit_inv(BIT_UV_FEAT_AIV, &uv_info.uv_feature_indications))
+		kvm_s390_gisa_disable(kvm);
+
 	kvm_for_each_vcpu(i, vcpu, kvm) {
 		mutex_lock(&vcpu->mutex);
 		r = kvm_s390_pv_create_cpu(vcpu, rc, rrc);
@@ -3350,9 +3357,7 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 
 	vcpu->arch.sie_block->icpua = vcpu->vcpu_id;
 	spin_lock_init(&vcpu->arch.local_int.lock);
-	vcpu->arch.sie_block->gd = (u32)(u64)vcpu->kvm->arch.gisa_int.origin;
-	if (vcpu->arch.sie_block->gd && sclp.has_gisaf)
-		vcpu->arch.sie_block->gd |= GISA_FORMAT1;
+	vcpu->arch.sie_block->gd = kvm_s390_get_gisa_desc(vcpu->kvm);
 	seqcount_init(&vcpu->arch.cputm_seqcount);
 
 	vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
@@ -3956,14 +3961,12 @@ static int kvm_s390_handle_requests(struct kvm_vcpu *vcpu)
 	return 0;
 }
 
-void kvm_s390_set_tod_clock(struct kvm *kvm,
-			    const struct kvm_s390_vm_tod_clock *gtod)
+static void __kvm_s390_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clock *gtod)
 {
 	struct kvm_vcpu *vcpu;
 	union tod_clock clk;
 	unsigned long i;
 
-	mutex_lock(&kvm->lock);
 	preempt_disable();
 
 	store_tod_clock_ext(&clk);
@@ -3984,7 +3987,22 @@ void kvm_s390_set_tod_clock(struct kvm *kvm,
 
 	kvm_s390_vcpu_unblock_all(kvm);
 	preempt_enable();
+}
+
+void kvm_s390_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clock *gtod)
+{
+	mutex_lock(&kvm->lock);
+	__kvm_s390_set_tod_clock(kvm, gtod);
+	mutex_unlock(&kvm->lock);
+}
+
+int kvm_s390_try_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clock *gtod)
+{
+	if (!mutex_trylock(&kvm->lock))
+		return 0;
+	__kvm_s390_set_tod_clock(kvm, gtod);
 	mutex_unlock(&kvm->lock);
+	return 1;
 }
 
 /**

arch/s390/kvm/kvm-s390.h

@@ -231,6 +231,15 @@ static inline unsigned long kvm_s390_get_gfn_end(struct kvm_memslots *slots)
 	return ms->base_gfn + ms->npages;
 }
 
+static inline u32 kvm_s390_get_gisa_desc(struct kvm *kvm)
+{
+	u32 gd = (u32)(u64)kvm->arch.gisa_int.origin;
+
+	if (gd && sclp.has_gisaf)
+		gd |= GISA_FORMAT1;
+	return gd;
+}
+
 /* implemented in pv.c */
 int kvm_s390_pv_destroy_cpu(struct kvm_vcpu *vcpu, u16 *rc, u16 *rrc);
 int kvm_s390_pv_create_cpu(struct kvm_vcpu *vcpu, u16 *rc, u16 *rrc);
@@ -349,8 +358,8 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu);
 int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu);
 
 /* implemented in kvm-s390.c */
-void kvm_s390_set_tod_clock(struct kvm *kvm,
-			    const struct kvm_s390_vm_tod_clock *gtod);
+void kvm_s390_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clock *gtod);
+int kvm_s390_try_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clock *gtod);
 long kvm_arch_fault_in_page(struct kvm_vcpu *vcpu, gpa_t gpa, int writable);
 int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long addr);
 int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr);
@@ -450,6 +459,8 @@ int kvm_s390_get_irq_state(struct kvm_vcpu *vcpu,
 void kvm_s390_gisa_init(struct kvm *kvm);
 void kvm_s390_gisa_clear(struct kvm *kvm);
 void kvm_s390_gisa_destroy(struct kvm *kvm);
+void kvm_s390_gisa_disable(struct kvm *kvm);
+void kvm_s390_gisa_enable(struct kvm *kvm);
 int kvm_s390_gib_init(u8 nisc);
 void kvm_s390_gib_destroy(void);
 

arch/s390/kvm/priv.c

@@ -102,7 +102,20 @@ static int handle_set_clock(struct kvm_vcpu *vcpu)
 		return kvm_s390_inject_prog_cond(vcpu, rc);
 
 	VCPU_EVENT(vcpu, 3, "SCK: setting guest TOD to 0x%llx", gtod.tod);
-	kvm_s390_set_tod_clock(vcpu->kvm, &gtod);
+	/*
+	 * To set the TOD clock the kvm lock must be taken, but the vcpu lock
+	 * is already held in handle_set_clock. The usual lock order is the
+	 * opposite.  As SCK is deprecated and should not be used in several
+	 * cases, for example when the multiple epoch facility or TOD clock
+	 * steering facility is installed (see Principles of Operation),  a
+	 * slow path can be used.  If the lock can not be taken via try_lock,
+	 * the instruction will be retried via -EAGAIN at a later point in
+	 * time.
+	 */
+	if (!kvm_s390_try_set_tod_clock(vcpu->kvm, &gtod)) {
+		kvm_s390_retry_instr(vcpu);
+		return -EAGAIN;
+	}
 
 	kvm_s390_set_psw_cc(vcpu, 0);
 	return 0;