From 5be2226f417d5b06d17e6c52d6e341cf43c29e48 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 15 Feb 2022 13:07:10 -0500 Subject: [PATCH] KVM: x86: allow defining return-0 static calls A few vendor callbacks are only used by VMX, but they return an integer or bool value. Introduce KVM_X86_OP_OPTIONAL_RET0 for them: if a func is NULL in struct kvm_x86_ops, it will be changed to __static_call_return0 when updating static calls. Reviewed-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm-x86-ops.h | 15 +++++++++------ arch/x86/include/asm/kvm_host.h | 4 ++++ arch/x86/kvm/svm/avic.c | 5 ----- arch/x86/kvm/svm/svm.c | 20 -------------------- arch/x86/kvm/x86.c | 4 ++-- kernel/static_call.c | 1 + 6 files changed, 16 insertions(+), 33 deletions(-) diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h index c0ec066a8599..29affccb353c 100644 --- a/arch/x86/include/asm/kvm-x86-ops.h +++ b/arch/x86/include/asm/kvm-x86-ops.h @@ -10,7 +10,9 @@ BUILD_BUG_ON(1) * * KVM_X86_OP_OPTIONAL() can be used for those functions that can have * a NULL definition, for example if "static_call_cond()" will be used - * at the call sites. + * at the call sites. KVM_X86_OP_OPTIONAL_RET0() can be used likewise + * to make a definition optional, but in this case the default will + * be __static_call_return0. */ KVM_X86_OP(hardware_enable) KVM_X86_OP(hardware_disable) @@ -77,15 +79,15 @@ KVM_X86_OP(check_apicv_inhibit_reasons) KVM_X86_OP(refresh_apicv_exec_ctrl) KVM_X86_OP_OPTIONAL(hwapic_irr_update) KVM_X86_OP_OPTIONAL(hwapic_isr_update) -KVM_X86_OP_OPTIONAL(guest_apic_has_interrupt) +KVM_X86_OP_OPTIONAL_RET0(guest_apic_has_interrupt) KVM_X86_OP_OPTIONAL(load_eoi_exitmap) KVM_X86_OP_OPTIONAL(set_virtual_apic_mode) KVM_X86_OP_OPTIONAL(set_apic_access_page_addr) KVM_X86_OP(deliver_interrupt) KVM_X86_OP_OPTIONAL(sync_pir_to_irr) -KVM_X86_OP(set_tss_addr) -KVM_X86_OP(set_identity_map_addr) -KVM_X86_OP(get_mt_mask) +KVM_X86_OP_OPTIONAL_RET0(set_tss_addr) +KVM_X86_OP_OPTIONAL_RET0(set_identity_map_addr) +KVM_X86_OP_OPTIONAL_RET0(get_mt_mask) KVM_X86_OP(load_mmu_pgd) KVM_X86_OP(has_wbinvd_exit) KVM_X86_OP(get_l2_tsc_offset) @@ -103,7 +105,7 @@ KVM_X86_OP_OPTIONAL(vcpu_unblocking) KVM_X86_OP_OPTIONAL(pi_update_irte) KVM_X86_OP_OPTIONAL(pi_start_assignment) KVM_X86_OP_OPTIONAL(apicv_post_state_restore) -KVM_X86_OP_OPTIONAL(dy_apicv_has_pending_interrupt) +KVM_X86_OP_OPTIONAL_RET0(dy_apicv_has_pending_interrupt) KVM_X86_OP_OPTIONAL(set_hv_timer) KVM_X86_OP_OPTIONAL(cancel_hv_timer) KVM_X86_OP(setup_mce) @@ -127,3 +129,4 @@ KVM_X86_OP(vcpu_deliver_sipi_vector) #undef KVM_X86_OP #undef KVM_X86_OP_OPTIONAL +#undef KVM_X86_OP_OPTIONAL_RET0 diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index a7e82fc1f1f3..8e512f25a930 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1541,6 +1541,7 @@ extern struct kvm_x86_ops kvm_x86_ops; #define KVM_X86_OP(func) \ DECLARE_STATIC_CALL(kvm_x86_##func, *(((struct kvm_x86_ops *)0)->func)); #define KVM_X86_OP_OPTIONAL KVM_X86_OP +#define KVM_X86_OP_OPTIONAL_RET0 KVM_X86_OP #include static inline void kvm_ops_static_call_update(void) @@ -1550,6 +1551,9 @@ static inline void kvm_ops_static_call_update(void) #define KVM_X86_OP(func) \ WARN_ON(!kvm_x86_ops.func); __KVM_X86_OP(func) #define KVM_X86_OP_OPTIONAL __KVM_X86_OP +#define KVM_X86_OP_OPTIONAL_RET0(func) \ + static_call_update(kvm_x86_##func, kvm_x86_ops.func ? : \ + (void *) __static_call_return0); #include #undef __KVM_X86_OP } diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index 4245cb99b497..d4fa8c4f3a9a 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -650,11 +650,6 @@ void avic_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu) avic_set_pi_irte_mode(vcpu, activated); } -bool avic_dy_apicv_has_pending_interrupt(struct kvm_vcpu *vcpu) -{ - return false; -} - static void svm_ir_list_del(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi) { unsigned long flags; diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 3daca34020fa..7038c76fa841 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -3528,16 +3528,6 @@ static void svm_enable_nmi_window(struct kvm_vcpu *vcpu) svm->vmcb->save.rflags |= (X86_EFLAGS_TF | X86_EFLAGS_RF); } -static int svm_set_tss_addr(struct kvm *kvm, unsigned int addr) -{ - return 0; -} - -static int svm_set_identity_map_addr(struct kvm *kvm, u64 ident_addr) -{ - return 0; -} - static void svm_flush_tlb_current(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); @@ -3934,11 +3924,6 @@ static bool svm_has_emulated_msr(struct kvm *kvm, u32 index) return true; } -static u64 svm_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) -{ - return 0; -} - static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); @@ -4593,10 +4578,6 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .check_apicv_inhibit_reasons = avic_check_apicv_inhibit_reasons, .apicv_post_state_restore = avic_apicv_post_state_restore, - .set_tss_addr = svm_set_tss_addr, - .set_identity_map_addr = svm_set_identity_map_addr, - .get_mt_mask = svm_get_mt_mask, - .get_exit_info = svm_get_exit_info, .vcpu_after_set_cpuid = svm_vcpu_after_set_cpuid, @@ -4621,7 +4602,6 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .nested_ops = &svm_nested_ops, .deliver_interrupt = svm_deliver_interrupt, - .dy_apicv_has_pending_interrupt = avic_dy_apicv_has_pending_interrupt, .pi_update_irte = avic_pi_update_irte, .setup_mce = svm_setup_mce, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ab1c4778824a..16d29d41908f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -131,6 +131,7 @@ struct kvm_x86_ops kvm_x86_ops __read_mostly; DEFINE_STATIC_CALL_NULL(kvm_x86_##func, \ *(((struct kvm_x86_ops *)0)->func)); #define KVM_X86_OP_OPTIONAL KVM_X86_OP +#define KVM_X86_OP_OPTIONAL_RET0 KVM_X86_OP #include EXPORT_STATIC_CALL_GPL(kvm_x86_get_cs_db_l_bits); EXPORT_STATIC_CALL_GPL(kvm_x86_cache_reg); @@ -12016,8 +12017,7 @@ void kvm_arch_flush_shadow_memslot(struct kvm *kvm, static inline bool kvm_guest_apic_has_interrupt(struct kvm_vcpu *vcpu) { return (is_guest_mode(vcpu) && - kvm_x86_ops.guest_apic_has_interrupt && - static_call(kvm_x86_guest_apic_has_interrupt)(vcpu)); + static_call(kvm_x86_guest_apic_has_interrupt)(vcpu)); } static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu) diff --git a/kernel/static_call.c b/kernel/static_call.c index 43ba0b1e0edb..f2b8baea35d2 100644 --- a/kernel/static_call.c +++ b/kernel/static_call.c @@ -503,6 +503,7 @@ long __static_call_return0(void) { return 0; } +EXPORT_SYMBOL_GPL(__static_call_return0); #ifdef CONFIG_STATIC_CALL_SELFTEST