[PATCH v2 01/15] KVM: s390: refactor crypto initialization

From: Tony Krowiak
Date: Tue Feb 27 2018 - 09:28:39 EST


The crypto control block designation (CRYCBD) is a 32-bit
field in the KVM guest's SIE state description. The
contents of bits 1-28 of this field, with three zero bits
appended on the right, designate the host real 31-bit
address of a crypto control block (CRYCB). Bits 30-31
specify the format of the CRYCB. In the current
implementation, the address of the CRYCB is stored in
the CRYCBD only if the Message-Security-Assist extension
3 (MSA3) facility is installed. Virtualization of AP
facilities, however, requires that a CRYCB of the
appropriate format be made available to SIE regardless
of whether MSA3 is installed or not.

This patch introduces a new compilation unit to provide
all interfaces related to configuration of AP facilities.
Let's start by moving the function for setting the CRYCB
format from arch/s390/kvm/kvm-s390 to this new AP
configuration interface.

Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx>
---
MAINTAINERS | 10 ++++++
arch/s390/include/asm/kvm-ap.h | 16 ++++++++++
arch/s390/include/asm/kvm_host.h | 1 +
arch/s390/kvm/Makefile | 2 +-
arch/s390/kvm/kvm-ap.c | 47 ++++++++++++++++++++++++++++
arch/s390/kvm/kvm-s390.c | 62 +++++---------------------------------
6 files changed, 83 insertions(+), 55 deletions(-)
create mode 100644 arch/s390/include/asm/kvm-ap.h
create mode 100644 arch/s390/kvm/kvm-ap.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 0ec5881..4acf7c2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11875,6 +11875,16 @@ W: http://www.ibm.com/developerworks/linux/linux390/
S: Supported
F: drivers/s390/crypto/

+S390 VFIO AP DRIVER
+M: Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx>
+M: Christian BornTraeger <borntraeger@xxxxxxxxxx>
+M: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
+L: linux-s390@xxxxxxxxxxxxxxx
+W: http://www.ibm.com/developerworks/linux/linux390/
+S: Supported
+F: arch/s390/include/asm/kvm/kvm-ap.h
+F: arch/s390/kvm/kvm-ap.c
+
S390 ZFCP DRIVER
M: Steffen Maier <maier@xxxxxxxxxxxxxxxxxx>
M: Benjamin Block <bblock@xxxxxxxxxxxxxxxxxx>
diff --git a/arch/s390/include/asm/kvm-ap.h b/arch/s390/include/asm/kvm-ap.h
new file mode 100644
index 0000000..4e43117
--- /dev/null
+++ b/arch/s390/include/asm/kvm-ap.h
@@ -0,0 +1,16 @@
+/*
+ * Adjunct Processor (AP) configuration management for KVM guests
+ *
+ * Copyright IBM Corp. 2017
+ *
+ * Author(s): Tony Krowiak <akrowia@xxxxxxxxxxxxxxxxxx>
+ */
+
+#ifndef _ASM_KVM_AP
+#define _ASM_KVM_AP
+#include <linux/types.h>
+#include <linux/kvm_host.h>
+
+void kvm_ap_set_crycb_format(struct kvm *kvm, __u32 *crycbd);
+
+#endif /* _ASM_KVM_AP */
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 27918b1..a4c77d3 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -257,6 +257,7 @@ struct kvm_s390_sie_block {
__u8 reservedf0[12]; /* 0x00f0 */
#define CRYCB_FORMAT1 0x00000001
#define CRYCB_FORMAT2 0x00000003
+#define CRYCB_FORMAT_MASK 0x00000003
__u32 crycbd; /* 0x00fc */
__u64 gcr[16]; /* 0x0100 */
__u64 gbea; /* 0x0180 */
diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile
index 05ee90a..1876bfe 100644
--- a/arch/s390/kvm/Makefile
+++ b/arch/s390/kvm/Makefile
@@ -9,6 +9,6 @@ common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/async_pf.o $(KVM)/irqch
ccflags-y := -Ivirt/kvm -Iarch/s390/kvm

kvm-objs := $(common-objs) kvm-s390.o intercept.o interrupt.o priv.o sigp.o
-kvm-objs += diag.o gaccess.o guestdbg.o vsie.o
+kvm-objs += diag.o gaccess.o guestdbg.o vsie.o kvm-ap.o

obj-$(CONFIG_KVM) += kvm.o
diff --git a/arch/s390/kvm/kvm-ap.c b/arch/s390/kvm/kvm-ap.c
new file mode 100644
index 0000000..5305f4c
--- /dev/null
+++ b/arch/s390/kvm/kvm-ap.c
@@ -0,0 +1,47 @@
+/*
+ * Adjunct Processor (AP) configuration management for KVM guests
+ *
+ * Copyright IBM Corp. 2017
+ *
+ * Author(s): Tony Krowiak <akrowia@xxxxxxxxxxxxxxxxxx>
+ */
+
+#include <asm/kvm-ap.h>
+#include <asm/ap.h>
+
+#include "kvm-s390.h"
+
+static int kvm_ap_apxa_installed(void)
+{
+ int ret;
+ struct ap_config_info config;
+
+ ret = ap_query_configuration(&config);
+ if (ret)
+ return 0;
+
+ return (config.apxa == 1);
+}
+
+/**
+ * kvm_ap_set_crycb_format
+ *
+ * Set the CRYCB format in the CRYCBD for the KVM guest.
+ *
+ * @kvm: the KVM guest
+ * @crycbd: the CRYCB descriptor
+ */
+void kvm_ap_set_crycb_format(struct kvm *kvm, __u32 *crycbd)
+{
+ *crycbd = (__u32)(unsigned long) kvm->arch.crypto.crycb;
+
+ *crycbd &= ~(CRYCB_FORMAT_MASK);
+
+ /* If the MSAX3 is installed */
+ if (test_kvm_facility(kvm, 76)) {
+ if (kvm_ap_apxa_installed())
+ *crycbd |= CRYCB_FORMAT2;
+ else
+ *crycbd |= CRYCB_FORMAT1;
+ }
+}
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 5f5a4cb..de1e299 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -40,6 +40,8 @@
#include <asm/sclp.h>
#include <asm/cpacf.h>
#include <asm/timex.h>
+#include <asm/ap.h>
+#include <asm/kvm-ap.h>
#include "kvm-s390.h"
#include "gaccess.h"

@@ -1853,55 +1855,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
return r;
}

-static int kvm_s390_query_ap_config(u8 *config)
-{
- u32 fcn_code = 0x04000000UL;
- u32 cc = 0;
-
- memset(config, 0, 128);
- asm volatile(
- "lgr 0,%1\n"
- "lgr 2,%2\n"
- ".long 0xb2af0000\n" /* PQAP(QCI) */
- "0: ipm %0\n"
- "srl %0,28\n"
- "1:\n"
- EX_TABLE(0b, 1b)
- : "+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(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 u64 kvm_s390_get_initial_cpuid(void)
{
struct cpuid cpuid;
@@ -1913,12 +1866,13 @@ static u64 kvm_s390_get_initial_cpuid(void)

static void kvm_s390_crypto_init(struct kvm *kvm)
{
+ kvm->arch.crypto.crycb = &kvm->arch.sie_page2->crycb;
+ kvm->arch.crypto.crycbd = (__u32)(unsigned long) kvm->arch.crypto.crycb;
+ kvm_ap_set_crycb_format(kvm, &kvm->arch.crypto.crycbd);
+
if (!test_kvm_facility(kvm, 76))
return;

- kvm->arch.crypto.crycb = &kvm->arch.sie_page2->crycb;
- kvm_s390_set_crycb_format(kvm);
-
/* Enable AES/DEA protected key functions by default */
kvm->arch.crypto.aes_kw = 1;
kvm->arch.crypto.dea_kw = 1;
@@ -2446,6 +2400,8 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)

static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu)
{
+ vcpu->arch.sie_block->crycbd = vcpu->kvm->arch.crypto.crycbd;
+
if (!test_kvm_facility(vcpu->kvm, 76))
return;

@@ -2455,8 +2411,6 @@ static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu)
vcpu->arch.sie_block->ecb3 |= ECB3_AES;
if (vcpu->kvm->arch.crypto.dea_kw)
vcpu->arch.sie_block->ecb3 |= ECB3_DEA;
-
- vcpu->arch.sie_block->crycbd = vcpu->kvm->arch.crypto.crycbd;
}

void kvm_s390_vcpu_unsetup_cmma(struct kvm_vcpu *vcpu)
--
1.7.1