KVM: CPACF: Enable MSA4 instructions for kvm guest

We have to provide a per guest crypto block for the CPUs to
enable MSA4 instructions. According to icainfo on z196 or
later this enables CCM-AES-128, CMAC-AES-128, CMAC-AES-192
and CMAC-AES-256.

Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[split MSA4/protected key into two patches]

2 files changed, 46 insertions, 1 deletions

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index a76a124dff48..1a6f6fd8bd34 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/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)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 628e992eeded..2037738d01a0 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/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);
@@ -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;
 }