Merge tag 'kvm-s390-next-20140910' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-next

KVM: s390: Fixes and features for next (3.18)

1. Crypto/CPACF support: To enable the MSA4 instructions we have to
   provide a common control structure for each SIE control block
2. Two cleanups found by a static code checker: one redundant assignment
   and one useless if
3. Fix the page handling of the diag10 ballooning interface. If the
   guest freed the pages at absolute 0 some checks and frees were
   incorrect
4. Limit guests to 16TB
5. Add __must_check to interrupt injection code

Author: bonzini

arch/s390/include/asm/kvm_host.h

@@ -157,7 +157,9 @@ struct kvm_s390_sie_block {
 	__u8	armid;			/* 0x00e3 */
 	__u8	reservede4[4];		/* 0x00e4 */
 	__u64	tecmc;			/* 0x00e8 */
-	__u8	reservedf0[16];		/* 0x00f0 */
+	__u8	reservedf0[12];		/* 0x00f0 */
+#define CRYCB_FORMAT1 0x00000001
+	__u32	crycbd;			/* 0x00fc */
 	__u64	gcr[16];		/* 0x0100 */
 	__u64	gbea;			/* 0x0180 */
 	__u8	reserved188[24];	/* 0x0188 */
@@ -410,6 +412,15 @@ struct s390_io_adapter {
 #define MAX_S390_IO_ADAPTERS ((MAX_ISC + 1) * 8)
 #define MAX_S390_ADAPTER_MAPS 256
 
+struct kvm_s390_crypto {
+	struct kvm_s390_crypto_cb *crycb;
+	__u32 crycbd;
+};
+
+struct kvm_s390_crypto_cb {
+	__u8    reserved00[128];                /* 0x0000 */
+};
+
 struct kvm_arch{
 	struct sca_block *sca;
 	debug_info_t *dbf;
@@ -423,6 +434,7 @@ struct kvm_arch{
 	struct s390_io_adapter *adapters[MAX_S390_IO_ADAPTERS];
 	wait_queue_head_t ipte_wq;
 	spinlock_t start_stop_lock;
+	struct kvm_s390_crypto crypto;
 };
 
 #define KVM_HVA_ERR_BAD		(-1UL)

arch/s390/kvm/diag.c

@@ -28,22 +28,32 @@ static int diag_release_pages(struct kvm_vcpu *vcpu)
 	start = vcpu->run->s.regs.gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4];
 	end = vcpu->run->s.regs.gprs[vcpu->arch.sie_block->ipa & 0xf] + 4096;
 
-	if (start & ~PAGE_MASK || end & ~PAGE_MASK || start > end
+	if (start & ~PAGE_MASK || end & ~PAGE_MASK || start >= end
 	    || start < 2 * PAGE_SIZE)
 		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 
 	VCPU_EVENT(vcpu, 5, "diag release pages %lX %lX", start, end);
 	vcpu->stat.diagnose_10++;
 
-	/* we checked for start > end above */
-	if (end < prefix || start >= prefix + 2 * PAGE_SIZE) {
+	/*
+	 * We checked for start >= end above, so lets check for the
+	 * fast path (no prefix swap page involved)
+	 */
+	if (end <= prefix || start >= prefix + 2 * PAGE_SIZE) {
 		gmap_discard(vcpu->arch.gmap, start, end);
 	} else {
-		if (start < prefix)
-			gmap_discard(vcpu->arch.gmap, start, prefix);
-		if (end >= prefix)
-			gmap_discard(vcpu->arch.gmap,
-				     prefix + 2 * PAGE_SIZE, end);
+		/*
+		 * This is slow path.  gmap_discard will check for start
+		 * so lets split this into before prefix, prefix, after
+		 * prefix and let gmap_discard make some of these calls
+		 * NOPs.
+		 */
+		gmap_discard(vcpu->arch.gmap, start, prefix);
+		if (start <= prefix)
+			gmap_discard(vcpu->arch.gmap, 0, 4096);
+		if (end > prefix + 4096)
+			gmap_discard(vcpu->arch.gmap, 4096, 8192);
+		gmap_discard(vcpu->arch.gmap, prefix + 2 * PAGE_SIZE, end);
 	}
 	return 0;
 }

arch/s390/kvm/gaccess.c

@@ -254,8 +254,7 @@ static void ipte_unlock_simple(struct kvm_vcpu *vcpu)
 		new = old = ACCESS_ONCE(*ic);
 		new.k = 0;
 	} while (cmpxchg(&ic->val, old.val, new.val) != old.val);
-	if (!ipte_lock_count)
-		wake_up(&vcpu->kvm->arch.ipte_wq);
+	wake_up(&vcpu->kvm->arch.ipte_wq);
 out:
 	mutex_unlock(&ipte_mutex);
 }

arch/s390/kvm/interrupt.c

@@ -28,7 +28,7 @@
 #define IOINT_AI_MASK 0x04000000
 #define PFAULT_INIT 0x0600
 
-static int deliver_ckc_interrupt(struct kvm_vcpu *vcpu);
+static int __must_check deliver_ckc_interrupt(struct kvm_vcpu *vcpu);
 
 static int is_ioint(u64 type)
 {
@@ -77,7 +77,7 @@ static u64 int_word_to_isc_bits(u32 int_word)
 	return (0x80 >> isc) << 24;
 }
 
-static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
+static int __must_check __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
 				      struct kvm_s390_interrupt_info *inti)
 {
 	switch (inti->type) {
@@ -86,6 +86,7 @@ static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
 			return 0;
 		if (vcpu->arch.sie_block->gcr[0] & 0x2000ul)
 			return 1;
+		return 0;
 	case KVM_S390_INT_EMERGENCY:
 		if (psw_extint_disabled(vcpu))
 			return 0;
@@ -225,7 +226,7 @@ static u16 get_ilc(struct kvm_vcpu *vcpu)
 	}
 }
 
-static int __deliver_prog_irq(struct kvm_vcpu *vcpu,
+static int __must_check __deliver_prog_irq(struct kvm_vcpu *vcpu,
 			      struct kvm_s390_pgm_info *pgm_info)
 {
 	int rc = 0;
@@ -307,7 +308,7 @@ static int __deliver_prog_irq(struct kvm_vcpu *vcpu,
 	return rc;
 }
 
-static int __do_deliver_interrupt(struct kvm_vcpu *vcpu,
+static int __must_check __do_deliver_interrupt(struct kvm_vcpu *vcpu,
 				   struct kvm_s390_interrupt_info *inti)
 {
 	const unsigned short table[] = { 2, 4, 4, 6 };
@@ -508,7 +509,7 @@ static int __do_deliver_interrupt(struct kvm_vcpu *vcpu,
 	return rc;
 }
 
-static int deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
+static int __must_check deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
 {
 	int rc;
 
@@ -657,7 +658,7 @@ void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu)
 			  &vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].ctrl);
 }
 
-int kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
+int __must_check kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
 {
 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 	struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
@@ -1351,7 +1352,6 @@ static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
 		r = enqueue_floating_irq(dev, attr);
 		break;
 	case KVM_DEV_FLIC_CLEAR_IRQS:
-		r = 0;
 		kvm_s390_clear_float_irqs(dev->kvm);
 		break;
 	case KVM_DEV_FLIC_APF_ENABLE:

arch/s390/kvm/kvm-s390.c

@@ -392,6 +392,22 @@ long kvm_arch_vm_ioctl(struct file *filp,
 	return r;
 }
 
+static int kvm_s390_crypto_init(struct kvm *kvm)
+{
+	if (!test_vfacility(76))
+		return 0;
+
+	kvm->arch.crypto.crycb = kzalloc(sizeof(*kvm->arch.crypto.crycb),
+					 GFP_KERNEL | GFP_DMA);
+	if (!kvm->arch.crypto.crycb)
+		return -ENOMEM;
+
+	kvm->arch.crypto.crycbd = (__u32) (unsigned long) kvm->arch.crypto.crycb |
+				  CRYCB_FORMAT1;
+
+	return 0;
+}
+
 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 {
 	int rc;
@@ -429,6 +445,9 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	if (!kvm->arch.dbf)
 		goto out_nodbf;
 
+	if (kvm_s390_crypto_init(kvm) < 0)
+		goto out_crypto;
+
 	spin_lock_init(&kvm->arch.float_int.lock);
 	INIT_LIST_HEAD(&kvm->arch.float_int.list);
 	init_waitqueue_head(&kvm->arch.ipte_wq);
@@ -439,7 +458,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	if (type & KVM_VM_S390_UCONTROL) {
 		kvm->arch.gmap = NULL;
 	} else {
-		kvm->arch.gmap = gmap_alloc(current->mm, -1UL);
+		kvm->arch.gmap = gmap_alloc(current->mm, (1UL << 44) - 1);
 		if (!kvm->arch.gmap)
 			goto out_nogmap;
 		kvm->arch.gmap->private = kvm;
@@ -453,6 +472,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 
 	return 0;
 out_nogmap:
+	kfree(kvm->arch.crypto.crycb);
+out_crypto:
 	debug_unregister(kvm->arch.dbf);
 out_nodbf:
 	free_page((unsigned long)(kvm->arch.sca));
@@ -507,6 +528,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 	kvm_free_vcpus(kvm);
 	free_page((unsigned long)(kvm->arch.sca));
 	debug_unregister(kvm->arch.dbf);
+	kfree(kvm->arch.crypto.crycb);
 	if (!kvm_is_ucontrol(kvm))
 		gmap_free(kvm->arch.gmap);
 	kvm_s390_destroy_adapters(kvm);
@@ -588,6 +610,14 @@ int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 	return 0;
 }
 
+static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu)
+{
+	if (!test_vfacility(76))
+		return;
+
+	vcpu->arch.sie_block->crycbd = vcpu->kvm->arch.crypto.crycbd;
+}
+
 void kvm_s390_vcpu_unsetup_cmma(struct kvm_vcpu *vcpu)
 {
 	free_page(vcpu->arch.sie_block->cbrlo);
@@ -634,6 +664,9 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 	vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;
 	get_cpu_id(&vcpu->arch.cpu_id);
 	vcpu->arch.cpu_id.version = 0xff;
+
+	kvm_s390_vcpu_crypto_setup(vcpu);
+
 	return rc;
 }
 

arch/s390/kvm/kvm-s390.h

@@ -138,7 +138,7 @@ static inline int kvm_s390_user_cpu_state_ctrl(struct kvm *kvm)
 int kvm_s390_handle_wait(struct kvm_vcpu *vcpu);
 void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu);
 enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer);
-int kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu);
+int __must_check kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu);
 void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu);
 void kvm_s390_clear_float_irqs(struct kvm *kvm);
 int __must_check kvm_s390_inject_vm(struct kvm *kvm,