KVM: s390/CPACF: Choose crypto control block format
We need to specify a different format for the crypto control block
depending on whether the APXA facility is installed or not. Let's
test for it by executing the PQAP(QCI) function and use either a
format-1 or a format-2 crypto control block accordingly. This is a
host only change for z13 and does not affect the guest view.
Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 3acf08b..deac473 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -654,6 +654,52 @@
return r;
}
+static int kvm_s390_query_ap_config(u8 *config)
+{
+ u32 fcn_code = 0x04000000UL;
+ u32 cc;
+
+ asm volatile(
+ "lgr 0,%1\n"
+ "lgr 2,%2\n"
+ ".long 0xb2af0000\n" /* PQAP(QCI) */
+ "ipm %0\n"
+ "srl %0,28\n"
+ : "=r" (cc)
+ : "r" (fcn_code), "r" (config)
+ : "cc", "0", "2", "memory"
+ );
+
+ return cc;
+}
+
+static int kvm_s390_apxa_installed(void)
+{
+ u8 config[128];
+ int cc;
+
+ if (test_facility(2) && test_facility(12)) {
+ cc = kvm_s390_query_ap_config(config);
+
+ if (cc)
+ pr_err("PQAP(QCI) failed with cc=%d", cc);
+ else
+ return config[0] & 0x40;
+ }
+
+ return 0;
+}
+
+static void kvm_s390_set_crycb_format(struct kvm *kvm)
+{
+ kvm->arch.crypto.crycbd = (__u32)(unsigned long) kvm->arch.crypto.crycb;
+
+ if (kvm_s390_apxa_installed())
+ kvm->arch.crypto.crycbd |= CRYCB_FORMAT2;
+ else
+ kvm->arch.crypto.crycbd |= CRYCB_FORMAT1;
+}
+
static int kvm_s390_crypto_init(struct kvm *kvm)
{
if (!test_vfacility(76))
@@ -664,8 +710,7 @@
if (!kvm->arch.crypto.crycb)
return -ENOMEM;
- kvm->arch.crypto.crycbd = (__u32) (unsigned long) kvm->arch.crypto.crycb |
- CRYCB_FORMAT1;
+ kvm_s390_set_crycb_format(kvm);
/* Disable AES/DEA protected key functions by default */
kvm->arch.crypto.aes_kw = 0;