[PATCH v4 20/27] KVM: s390: arm64: Introduce host definitions
From: Steffen Eiden <seiden@linux.ibm.com>
Date: 2026-07-06 08:53:10
Also in:
kvm, kvmarm, linux-s390, lkml
Subsystem:
kernel virtual machine for s390 (kvm/s390), s390 architecture, the rest · Maintainers:
Christian Borntraeger, Janosch Frank, Claudio Imbrenda, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Linus Torvalds
Add all basic definitions the arm on s390 KVM host requires. Including, but not limited to, struct kvm*arch definitions, various functions (to be implemented in the following patches), and various defines required to run arm64 guests. Enlighten asm/kvm_host.h for the new header variant. The new header is chosen instead of asm/kvm_host_s390.h if KVM_S390_ARM64 is defined. Co-developed-by: Andreas Grapentin <redacted> Signed-off-by: Andreas Grapentin <redacted> Co-developed-by: Nina Schoetterl-Glausch <redacted> Signed-off-by: Nina Schoetterl-Glausch <redacted> Signed-off-by: Steffen Eiden <seiden@linux.ibm.com> --- arch/s390/include/asm/kvm.h | 6 + arch/s390/include/asm/kvm_host.h | 9 ++ arch/s390/include/asm/kvm_host_arm64.h | 210 +++++++++++++++++++++++++ 3 files changed, 225 insertions(+) create mode 100644 arch/s390/include/asm/kvm.h create mode 100644 arch/s390/include/asm/kvm_host_arm64.h
diff --git a/arch/s390/include/asm/kvm.h b/arch/s390/include/asm/kvm.h
new file mode 100644
index 000000000000..aeb11dc631d5
--- /dev/null
+++ b/arch/s390/include/asm/kvm.h@@ -0,0 +1,6 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifdef KVM_S390_ARM64 +#include <uapi/arm64/kvm.h> +#else +#include <uapi/asm/kvm.h> +#endif
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 33af8842a71c..0c22cc42be7e 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h@@ -3,7 +3,16 @@ #ifndef ASM_KVM_HOST_H #define ASM_KVM_HOST_H +#ifdef KVM_S390_ARM64 +#include <asm/kvm_host_arm64.h> +#else #include <asm/kvm_host_s390.h> +#endif + +static inline bool kvm_arch_pmi_in_guest(struct kvm_vcpu *vcpu) +{ + return false; +} #define PGM_PROTECTION 0x04 #define PGM_ADDRESSING 0x05
diff --git a/arch/s390/include/asm/kvm_host_arm64.h b/arch/s390/include/asm/kvm_host_arm64.h
new file mode 100644
index 000000000000..6d08856fe395
--- /dev/null
+++ b/arch/s390/include/asm/kvm_host_arm64.h@@ -0,0 +1,210 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef ASM_KVM_HOST_ARM64_H +#define ASM_KVM_HOST_ARM64_H + +#include <linux/bug.h> + +#include <asm/kvm_host_types.h> +#include <asm/debug.h> + +#define vcpu_gp_regs(v) ((v)->arch.sae_block.gpr) + +#define HAVE_KVM_MMIO + +#include <arm64/kvm_host.h> +#include <asm/sae.h> + +#define KVM_HAVE_MMU_RWLOCK +#define KVM_MAX_VCPUS 1 + +#define KVM_HALT_POLL_NS_DEFAULT 50000 + +/* Minimal (=no) vgic definitions */ +#define KVM_IRQCHIP_NUM_PINS 1 +#define irqchip_in_kernel(_v) false; + +#define __ctxt_sys_reg(ctx, reg) NULL +struct kvm_cpu_context { + /* + * These are just for 32 bit, which we don't have, making them RES0. + * They are exposed to user space. + */ + u64 spsr_abt; + u64 spsr_und; + u64 spsr_irq; + u64 spsr_fiq; + + __vector128 __aligned(16) vregs[32]; +}; + +struct kvm_vcpu_arch { + struct kvm_sae_block sae_block; + struct kvm_sae_save_area save_area; + struct kvm_cpu_context ctxt; + + u32 host_acrs[NUM_ACRS]; + + /* Hypervisor Configuration Register */ + u64 hcr_elz; + + /* Configuration flags, set once and for all before the vcpu can run */ + u8 cflags; + + /* Input flags to the hypervisor code, potentially cleared after use */ + u8 iflags; + + /* State flags for kernel bookkeeping, unused by the hypervisor code */ + u8 sflags; + + /* + * Don't run the guest (internal implementation need). + * + * Contrary to the flags above, this is set/cleared outside of + * a vcpu context, and thus cannot be mixed with the flags + * themselves (or the flag accesses need to be made atomic). + */ + bool pause; + + /* vcpu power state */ + struct kvm_mp_state mp_state; + /* lock for mp_state & reset_state.reset */ + spinlock_t mp_state_lock; + + /* vcpu reset state */ + struct vcpu_reset_state reset_state; + + /* GMAP */ + struct gmap *gmap; + struct kvm_s390_mmu_cache *mc; + + void *debugfs_state_data; +}; + +struct kvm_vcpu_stat { + struct kvm_vcpu_stat_generic generic; + /* ARM64 stats */ + u64 hvc_exit_stat; + u64 wfe_exit_stat; + u64 wfi_exit_stat; + u64 mmio_exit_user; + u64 mmio_exit_kernel; + u64 signal_exits; + u64 exits; + /* GMAP stats */ + u64 pfault_sync; +}; + +#define kvm_vcpu_get_sp_el1(__vcpu) (&((__vcpu)->arch.sae_block.sp_el1)) +#define kvm_vcpu_get_vreg(__vcpu, _off) (&(__vcpu)->arch.ctxt.vregs[_off]) +#define kvm_vcpu_get_vregs(__vcpu) (&(__vcpu)->arch.ctxt.vregs) +#define kvm_vcpu_get_fpsr(__vcpu) (&(__vcpu)->arch.sae_block.fpsr) +#define kvm_vcpu_get_fpcr(__vcpu) (&(__vcpu)->arch.sae_block.fpcr) + +#define __vcpu_flags_preempt_disable() preempt_disable() +#define __vcpu_flags_preempt_enable() preempt_enable() + +#define _vcpu_get_flag(v, flagset, ...) \ + __vcpu_get_flag(&(v)->arch.flagset, __VA_ARGS__) +#define _vcpu_set_flag(v, flagset, ...) \ + __vcpu_set_flag(&(v)->arch.flagset, __VA_ARGS__) +#define _vcpu_clear_flag(v, flagset, ...) \ + __vcpu_clear_flag(&(v)->arch.flagset, __VA_ARGS__) +#define _vcpu_test_and_clear_flag(v, flagset, ...) \ + __vcpu_test_and_clear_flag(&(v)->arch.flagset, __VA_ARGS__) + +#define kvm_has_mte(_kvm) false +#define vcpu_has_sve(_vcpu) false +#define vcpu_has_ptrauth(_vcpu) false + +struct kvm_arch_memory_slot { +}; + +struct kvm_arch { + struct gmap *gmap; + u64 guest_phys_size; + + /* VM-wide vCPU feature set */ + unsigned long flags; + + /* Protects VM-scoped configuration data */ + struct mutex config_lock; + + debug_info_t *dbf; + + DECLARE_BITMAP(vcpu_features, KVM_VCPU_MAX_FEATURES); + + unsigned long mem_limit; +}; + +static inline bool __vcpu_has_feature(const struct kvm_arch *ka, int feature) +{ + return test_bit(feature, ka->vcpu_features); +} + +#define vcpu_has_feature(v, f) __vcpu_has_feature(&(v)->kvm->arch, (f)) + +struct kvm_vm_stat { + struct kvm_vm_stat_generic generic; +}; + +#define kvm_vm_is_protected(_kvm) false + +#define vcpu_is_loaded(_vcpu) ((_vcpu)->cpu != -1) + +#define KVM_HVA_ERR_BAD -1UL +#define KVM_HVA_ERR_RO_BAD -2UL + +#define kvm_phys_size(__kvm) ((__kvm)->arch.guest_phys_size) +static inline bool kvm_is_error_hva(unsigned long addr) +{ + return IS_ERR_VALUE(addr); +} + +u32 get_kvm_ipa_limit(void); + +static inline void kvm_arch_sync_events(struct kvm *kvm) {} +static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} + +int kvm_handle_guest_abort(struct kvm_vcpu *vcpu); + +/* arm64 guests do not use async-pf. Defined because Kbuild requires it as s390 kvm turns it on. */ +#define ASYNC_PF_PER_VCPU 0 +struct kvm_arch_async_pf { + unsigned long pfault_token; +}; + +#define __unsupp_async_call(fn) WARN_ONCE(true, "async not supported on kvm-arm64 %s", fn) + +static inline bool kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu *vcpu) +{ + __unsupp_async_call(__func__); + return false; +}; + +static inline void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, + struct kvm_async_pf *work) +{ + __unsupp_async_call(__func__); +}; + +static inline bool kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu, + struct kvm_async_pf *work) +{ + __unsupp_async_call(__func__); + return false; +}; + +static inline void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, + struct kvm_async_pf *work) +{ + __unsupp_async_call(__func__); +}; + +static inline void kvm_arch_async_page_present_queued(struct kvm_vcpu *vcpu) +{ + __unsupp_async_call(__func__); +}; + +#define kvm_supports_32bit_el0() false + +#endif /* ASM_KVM_HOST_ARM64_H */
--
2.53.0