[PATCH v9 19/24] KVM: s390: Add basic arm64 kvm module

[Steffen Eiden <seiden@linux.ibm.com>]

Add basic code for the new arm64 on s390 KVM implementation.
Add kernel module boilerplate code and trivial functions.
Add tracing scaffolding.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
 arch/s390/kvm/arm64/arm.c   | 147 ++++++++++++++++++++++++++++++++++++
 arch/s390/kvm/arm64/arm.h   |  44 +++++++++++
 arch/s390/kvm/arm64/guest.c |  90 ++++++++++++++++++++++
 arch/s390/kvm/arm64/trace.h |  18 +++++
 4 files changed, 299 insertions(+)
 create mode 100644 arch/s390/kvm/arm64/arm.c
 create mode 100644 arch/s390/kvm/arm64/arm.h
 create mode 100644 arch/s390/kvm/arm64/guest.c
 create mode 100644 arch/s390/kvm/arm64/trace.h

diff --git a/arch/s390/kvm/arm64/arm.c b/arch/s390/kvm/arm64/arm.c
new file mode 100644
index 000000000000..acd46059b75e
--- /dev/null
+++ b/arch/s390/kvm/arm64/arm.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/miscdevice.h>
+#include <linux/kvm.h>
+#include <linux/kvm_types.h>
+#include <linux/kvm_host.h>
+
+#include "arm.h"
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
+static unsigned long system_supported_vcpu_features(void);
+
+#define __INCL_GEN_ARM_FILE
+#include "generated/arm.inc"
+#undef __INCL_GEN_ARM_FILE
+
+int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
+{
+	int ret;
+
+	switch (ext) {
+	case KVM_CAP_NR_VCPUS:
+	case KVM_CAP_MAX_VCPUS:
+	case KVM_CAP_MAX_VCPU_ID:
+		ret = KVM_MAX_VCPUS;
+		break;
+	case KVM_CAP_ARM_VM_IPA_SIZE:
+		ret = get_kvm_ipa_limit();
+		break;
+	case KVM_CAP_IOEVENTFD:
+	case KVM_CAP_PRE_FAULT_MEMORY:
+		ret = 1;
+		break;
+	default:
+		ret = 0;
+	}
+
+	return ret;
+}
+
+static u64 kvm_max_guest_address(void)
+{
+	u64 max_addr;
+
+	max_addr = min_t(u64, TASK_SIZE_MAX, sclp.hamax);
+	max_addr = max_t(u64, max_addr, SZ_1G - 1);
+	return ALIGN_DOWN(max_addr + 1, SZ_1G) - 1;
+}
+
+vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
+{
+	return VM_FAULT_SIGBUS;
+}
+
+long kvm_arch_dev_ioctl(struct file *filp,
+			unsigned int ioctl, unsigned long arg)
+{
+	return -EINVAL;
+}
+
+u32 get_kvm_ipa_limit(void)
+{
+	return fls64(kvm_max_guest_address() + 1) - 1;
+}
+
+int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
+{
+	return 0;
+}
+
+void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
+{
+}
+
+int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
+				    struct kvm_mp_state *mp_state)
+{
+	*mp_state = READ_ONCE(vcpu->arch.mp_state);
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
+				    struct kvm_mp_state *mp_state)
+{
+	return -EINVAL;
+}
+
+int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
+{
+	return 0;
+}
+
+static unsigned long system_supported_vcpu_features(void)
+{
+	unsigned long features = KVM_S390_ARM64_IMPL_FEATURES;
+
+	return features;
+}
+
+bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
+{
+	return false;
+}
+
+int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+		int irq_source_id, int level, bool line_status)
+{
+	return -EINVAL;
+}
+
+int kvm_set_routing_entry(struct kvm *kvm,
+			  struct kvm_kernel_irq_routing_entry *e,
+			  const struct kvm_irq_routing_entry *ue)
+{
+	return -EINVAL;
+}
+
+int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
+{
+	return 0;
+}
+
+long kvm_arch_vcpu_unlocked_ioctl(struct file *filp, unsigned int ioctl,
+				  unsigned long arg)
+{
+	return -ENOIOCTLCMD;
+}
+
+static int __init kvm_s390_arm64_init(void)
+{
+	if (!sclp.has_aef)
+		return -ENODEV;
+
+	return kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+}
+
+static __exit void kvm_s390_arm64_exit(void)
+{
+	kvm_exit();
+}
+
+module_init(kvm_s390_arm64_init);
+module_exit(kvm_s390_arm64_exit);
diff --git a/arch/s390/kvm/arm64/arm.h b/arch/s390/kvm/arm64/arm.h
new file mode 100644
index 000000000000..9d903916c896
--- /dev/null
+++ b/arch/s390/kvm/arm64/arm.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ARCH_S390_KVM_ARM64_H
+#define ARCH_S390_KVM_ARM64_H
+
+static __always_inline int kvm_is_ucontrol(struct kvm *kvm)
+{
+	return 0;
+}
+
+static __always_inline int __kvm_s390_pv_destroy_page(struct page *page)
+{
+	return 0;
+}
+
+static __always_inline void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, gpa_t start, gpa_t end)
+{
+}
+
+static __always_inline int kvm_s390_pv_get_handle(struct kvm *kvm)
+{
+	return 0;
+}
+
+static __always_inline int kvm_s390_is_migration_mode(struct kvm *kvm)
+{
+	return false;
+}
+
+static __always_inline bool kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu)
+{
+	return false;
+}
+
+static __always_inline void kvm_s390_update_cmma_dirty(struct kvm *kvm, const struct kvm_memory_slot *old)
+{
+}
+
+/* should never be called */
+static __always_inline int kvm_s390_vm_stop_migration(struct kvm *kvm)
+{
+	return -EINVAL;
+}
+
+#endif /* ARCH_S390_KVM_ARM64_H */
diff --git a/arch/s390/kvm/arm64/guest.c b/arch/s390/kvm/arm64/guest.c
new file mode 100644
index 000000000000..1bf546bded81
--- /dev/null
+++ b/arch/s390/kvm/arm64/guest.c
@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kvm_host.h>
+#include <linux/kvm.h>
+
+#include <arm64/kvm_emulate.h>
+#include <arm64/kvm_nested.h>
+
+#define __INCL_GEN_ARM_FILE
+#include "generated/guest.inc"
+#undef __INCL_GEN_ARM_FILE
+
+const struct kvm_stats_desc kvm_vm_stats_desc[] = {
+	KVM_GENERIC_VM_STATS()
+};
+
+const struct kvm_stats_header kvm_vm_stats_header = {
+	.name_size = KVM_STATS_NAME_SIZE,
+	.num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
+	.id_offset =  sizeof(struct kvm_stats_header),
+	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
+	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
+		       sizeof(kvm_vm_stats_desc),
+};
+
+const struct kvm_stats_desc kvm_vcpu_stats_desc[] = {
+	KVM_GENERIC_VCPU_STATS(),
+	/* ARM64 stats */
+	STATS_DESC_COUNTER(VCPU, hvc_exit_stat),
+	STATS_DESC_COUNTER(VCPU, wfe_exit_stat),
+	STATS_DESC_COUNTER(VCPU, wfi_exit_stat),
+	STATS_DESC_COUNTER(VCPU, mmio_exit_user),
+	STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
+	STATS_DESC_COUNTER(VCPU, signal_exits),
+	STATS_DESC_COUNTER(VCPU, exits),
+	/* GMAP stats */
+	STATS_DESC_COUNTER(VCPU, pfault_sync),
+};
+
+const struct kvm_stats_header kvm_vcpu_stats_header = {
+	.name_size = KVM_STATS_NAME_SIZE,
+	.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
+	.id_offset = sizeof(struct kvm_stats_header),
+	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
+	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
+		       sizeof(kvm_vcpu_stats_desc),
+};
+
+int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+	return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+	return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
+				  struct kvm_sregs *sregs)
+{
+	return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
+				  struct kvm_sregs *sregs)
+{
+	return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+	return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+	return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
+				  struct kvm_translation *tr)
+{
+	return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
+					struct kvm_guest_debug *dbg)
+{
+	return -EINVAL;
+}
diff --git a/arch/s390/kvm/arm64/trace.h b/arch/s390/kvm/arm64/trace.h
new file mode 100644
index 000000000000..3a5dcd039c13
--- /dev/null
+++ b/arch/s390/kvm/arm64/trace.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#if !defined(KVM_ARM64_TRACE_KVM_H) || defined(TRACE_HEADER_MULTI_READ)
+#define KVM_ARM64_TRACE_KVM_H
+
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM kvm
+
+#endif /* KVM_ARM64_TRACE_KVM_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
-- 
2.53.0