KVM: x86: Copy kvm_x86_ops by value to eliminate layer of indirection

Replace the kvm_x86_ops pointer in common x86 with an instance of the
struct to save one pointer dereference when invoking functions.  Copy the
struct by value to set the ops during kvm_init().

Arbitrarily use kvm_x86_ops.hardware_enable to track whether or not the
ops have been initialized, i.e. a vendor KVM module has been loaded.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200321202603.19355-7-sean.j.christopherson@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -1274,22 +1274,22 @@ struct kvm_arch_async_pf {
 
 extern u64 __read_mostly host_efer;
 
-extern struct kvm_x86_ops *kvm_x86_ops;
+extern struct kvm_x86_ops kvm_x86_ops;
 extern struct kmem_cache *x86_fpu_cache;
 
 #define __KVM_HAVE_ARCH_VM_ALLOC
 static inline struct kvm *kvm_arch_alloc_vm(void)
 {
-	return __vmalloc(kvm_x86_ops->vm_size,
+	return __vmalloc(kvm_x86_ops.vm_size,
 			 GFP_KERNEL_ACCOUNT | __GFP_ZERO, PAGE_KERNEL);
 }
 void kvm_arch_free_vm(struct kvm *kvm);
 
 #define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLB
 static inline int kvm_arch_flush_remote_tlb(struct kvm *kvm)
 {
-	if (kvm_x86_ops->tlb_remote_flush &&
-	    !kvm_x86_ops->tlb_remote_flush(kvm))
+	if (kvm_x86_ops.tlb_remote_flush &&
+	    !kvm_x86_ops.tlb_remote_flush(kvm))
 		return 0;
 	else
 		return -ENOTSUPP;
@@ -1375,7 +1375,7 @@ extern u64 kvm_mce_cap_supported;
  *
  * EMULTYPE_SKIP - Set when emulating solely to skip an instruction, i.e. to
  *		   decode the instruction length.  For use *only* by
- *		   kvm_x86_ops->skip_emulated_instruction() implementations.
+ *		   kvm_x86_ops.skip_emulated_instruction() implementations.
  *
  * EMULTYPE_ALLOW_RETRY_PF - Set when the emulator should resume the guest to
  *			     retry native execution under certain conditions,
@@ -1669,14 +1669,14 @@ static inline bool kvm_irq_is_postable(struct kvm_lapic_irq *irq)
 
 static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
 {
-	if (kvm_x86_ops->vcpu_blocking)
-		kvm_x86_ops->vcpu_blocking(vcpu);
+	if (kvm_x86_ops.vcpu_blocking)
+		kvm_x86_ops.vcpu_blocking(vcpu);
 }
 
 static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
 {
-	if (kvm_x86_ops->vcpu_unblocking)
-		kvm_x86_ops->vcpu_unblocking(vcpu);
+	if (kvm_x86_ops.vcpu_unblocking)
+		kvm_x86_ops.vcpu_unblocking(vcpu);
 }
 
 static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}

arch/x86/kvm/cpuid.c

@@ -209,7 +209,7 @@ int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
 	vcpu->arch.cpuid_nent = cpuid->nent;
 	cpuid_fix_nx_cap(vcpu);
 	kvm_apic_set_version(vcpu);
-	kvm_x86_ops->cpuid_update(vcpu);
+	kvm_x86_ops.cpuid_update(vcpu);
 	r = kvm_update_cpuid(vcpu);
 
 out:
@@ -232,7 +232,7 @@ int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
 		goto out;
 	vcpu->arch.cpuid_nent = cpuid->nent;
 	kvm_apic_set_version(vcpu);
-	kvm_x86_ops->cpuid_update(vcpu);
+	kvm_x86_ops.cpuid_update(vcpu);
 	r = kvm_update_cpuid(vcpu);
 out:
 	return r;

arch/x86/kvm/hyperv.c

@@ -1022,7 +1022,7 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
 		addr = gfn_to_hva(kvm, gfn);
 		if (kvm_is_error_hva(addr))
 			return 1;
-		kvm_x86_ops->patch_hypercall(vcpu, instructions);
+		kvm_x86_ops.patch_hypercall(vcpu, instructions);
 		((unsigned char *)instructions)[3] = 0xc3; /* ret */
 		if (__copy_to_user((void __user *)addr, instructions, 4))
 			return 1;
@@ -1607,7 +1607,7 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
 	 * hypercall generates UD from non zero cpl and real mode
 	 * per HYPER-V spec
 	 */
-	if (kvm_x86_ops->get_cpl(vcpu) != 0 || !is_protmode(vcpu)) {
+	if (kvm_x86_ops.get_cpl(vcpu) != 0 || !is_protmode(vcpu)) {
 		kvm_queue_exception(vcpu, UD_VECTOR);
 		return 1;
 	}
@@ -1800,8 +1800,8 @@ int kvm_vcpu_ioctl_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
 	};
 	int i, nent = ARRAY_SIZE(cpuid_entries);
 
-	if (kvm_x86_ops->nested_get_evmcs_version)
-		evmcs_ver = kvm_x86_ops->nested_get_evmcs_version(vcpu);
+	if (kvm_x86_ops.nested_get_evmcs_version)
+		evmcs_ver = kvm_x86_ops.nested_get_evmcs_version(vcpu);
 
 	/* Skip NESTED_FEATURES if eVMCS is not supported */
 	if (!evmcs_ver)

arch/x86/kvm/kvm_cache_regs.h

@@ -68,7 +68,7 @@ static inline unsigned long kvm_register_read(struct kvm_vcpu *vcpu, int reg)
 		return 0;
 
 	if (!kvm_register_is_available(vcpu, reg))
-		kvm_x86_ops->cache_reg(vcpu, reg);
+		kvm_x86_ops.cache_reg(vcpu, reg);
 
 	return vcpu->arch.regs[reg];
 }
@@ -108,7 +108,7 @@ static inline u64 kvm_pdptr_read(struct kvm_vcpu *vcpu, int index)
 	might_sleep();  /* on svm */
 
 	if (!kvm_register_is_available(vcpu, VCPU_EXREG_PDPTR))
-		kvm_x86_ops->cache_reg(vcpu, VCPU_EXREG_PDPTR);
+		kvm_x86_ops.cache_reg(vcpu, VCPU_EXREG_PDPTR);
 
 	return vcpu->arch.walk_mmu->pdptrs[index];
 }
@@ -117,7 +117,7 @@ static inline ulong kvm_read_cr0_bits(struct kvm_vcpu *vcpu, ulong mask)
 {
 	ulong tmask = mask & KVM_POSSIBLE_CR0_GUEST_BITS;
 	if (tmask & vcpu->arch.cr0_guest_owned_bits)
-		kvm_x86_ops->decache_cr0_guest_bits(vcpu);
+		kvm_x86_ops.decache_cr0_guest_bits(vcpu);
 	return vcpu->arch.cr0 & mask;
 }
 
@@ -130,14 +130,14 @@ static inline ulong kvm_read_cr4_bits(struct kvm_vcpu *vcpu, ulong mask)
 {
 	ulong tmask = mask & KVM_POSSIBLE_CR4_GUEST_BITS;
 	if (tmask & vcpu->arch.cr4_guest_owned_bits)
-		kvm_x86_ops->decache_cr4_guest_bits(vcpu);
+		kvm_x86_ops.decache_cr4_guest_bits(vcpu);
 	return vcpu->arch.cr4 & mask;
 }
 
 static inline ulong kvm_read_cr3(struct kvm_vcpu *vcpu)
 {
 	if (!kvm_register_is_available(vcpu, VCPU_EXREG_CR3))
-		kvm_x86_ops->cache_reg(vcpu, VCPU_EXREG_CR3);
+		kvm_x86_ops.cache_reg(vcpu, VCPU_EXREG_CR3);
 	return vcpu->arch.cr3;
 }
 

arch/x86/kvm/lapic.c

@@ -463,7 +463,7 @@ static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
 	if (unlikely(vcpu->arch.apicv_active)) {
 		/* need to update RVI */
 		kvm_lapic_clear_vector(vec, apic->regs + APIC_IRR);
-		kvm_x86_ops->hwapic_irr_update(vcpu,
+		kvm_x86_ops.hwapic_irr_update(vcpu,
 				apic_find_highest_irr(apic));
 	} else {
 		apic->irr_pending = false;
@@ -488,7 +488,7 @@ static inline void apic_set_isr(int vec, struct kvm_lapic *apic)
 	 * just set SVI.
 	 */
 	if (unlikely(vcpu->arch.apicv_active))
-		kvm_x86_ops->hwapic_isr_update(vcpu, vec);
+		kvm_x86_ops.hwapic_isr_update(vcpu, vec);
 	else {
 		++apic->isr_count;
 		BUG_ON(apic->isr_count > MAX_APIC_VECTOR);
@@ -536,7 +536,7 @@ static inline void apic_clear_isr(int vec, struct kvm_lapic *apic)
 	 * and must be left alone.
 	 */
 	if (unlikely(vcpu->arch.apicv_active))
-		kvm_x86_ops->hwapic_isr_update(vcpu,
+		kvm_x86_ops.hwapic_isr_update(vcpu,
 					       apic_find_highest_isr(apic));
 	else {
 		--apic->isr_count;
@@ -674,7 +674,7 @@ static int apic_has_interrupt_for_ppr(struct kvm_lapic *apic, u32 ppr)
 {
 	int highest_irr;
 	if (apic->vcpu->arch.apicv_active)
-		highest_irr = kvm_x86_ops->sync_pir_to_irr(apic->vcpu);
+		highest_irr = kvm_x86_ops.sync_pir_to_irr(apic->vcpu);
 	else
 		highest_irr = apic_find_highest_irr(apic);
 	if (highest_irr == -1 || (highest_irr & 0xF0) <= ppr)
@@ -1063,7 +1063,7 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
 						       apic->regs + APIC_TMR);
 		}
 
-		if (kvm_x86_ops->deliver_posted_interrupt(vcpu, vector)) {
+		if (kvm_x86_ops.deliver_posted_interrupt(vcpu, vector)) {
 			kvm_lapic_set_irr(vector, apic);
 			kvm_make_request(KVM_REQ_EVENT, vcpu);
 			kvm_vcpu_kick(vcpu);
@@ -1746,7 +1746,7 @@ static void cancel_hv_timer(struct kvm_lapic *apic)
 {
 	WARN_ON(preemptible());
 	WARN_ON(!apic->lapic_timer.hv_timer_in_use);
-	kvm_x86_ops->cancel_hv_timer(apic->vcpu);
+	kvm_x86_ops.cancel_hv_timer(apic->vcpu);
 	apic->lapic_timer.hv_timer_in_use = false;
 }
 
@@ -1757,13 +1757,13 @@ static bool start_hv_timer(struct kvm_lapic *apic)
 	bool expired;
 
 	WARN_ON(preemptible());
-	if (!kvm_x86_ops->set_hv_timer)
+	if (!kvm_x86_ops.set_hv_timer)
 		return false;
 
 	if (!ktimer->tscdeadline)
 		return false;
 
-	if (kvm_x86_ops->set_hv_timer(vcpu, ktimer->tscdeadline, &expired))
+	if (kvm_x86_ops.set_hv_timer(vcpu, ktimer->tscdeadline, &expired))
 		return false;
 
 	ktimer->hv_timer_in_use = true;
@@ -2190,7 +2190,7 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
 		kvm_apic_set_x2apic_id(apic, vcpu->vcpu_id);
 
 	if ((old_value ^ value) & (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE))
-		kvm_x86_ops->set_virtual_apic_mode(vcpu);
+		kvm_x86_ops.set_virtual_apic_mode(vcpu);
 
 	apic->base_address = apic->vcpu->arch.apic_base &
 			     MSR_IA32_APICBASE_BASE;
@@ -2268,9 +2268,9 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
 	vcpu->arch.pv_eoi.msr_val = 0;
 	apic_update_ppr(apic);
 	if (vcpu->arch.apicv_active) {
-		kvm_x86_ops->apicv_post_state_restore(vcpu);
-		kvm_x86_ops->hwapic_irr_update(vcpu, -1);
-		kvm_x86_ops->hwapic_isr_update(vcpu, -1);
+		kvm_x86_ops.apicv_post_state_restore(vcpu);
+		kvm_x86_ops.hwapic_irr_update(vcpu, -1);
+		kvm_x86_ops.hwapic_isr_update(vcpu, -1);
 	}
 
 	vcpu->arch.apic_arb_prio = 0;
@@ -2521,10 +2521,10 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s)
 	kvm_apic_update_apicv(vcpu);
 	apic->highest_isr_cache = -1;
 	if (vcpu->arch.apicv_active) {
-		kvm_x86_ops->apicv_post_state_restore(vcpu);
-		kvm_x86_ops->hwapic_irr_update(vcpu,
+		kvm_x86_ops.apicv_post_state_restore(vcpu);
+		kvm_x86_ops.hwapic_irr_update(vcpu,
 				apic_find_highest_irr(apic));
-		kvm_x86_ops->hwapic_isr_update(vcpu,
+		kvm_x86_ops.hwapic_isr_update(vcpu,
 				apic_find_highest_isr(apic));
 	}
 	kvm_make_request(KVM_REQ_EVENT, vcpu);

arch/x86/kvm/mmu.h

@@ -98,8 +98,8 @@ static inline unsigned long kvm_get_active_pcid(struct kvm_vcpu *vcpu)
 static inline void kvm_mmu_load_pgd(struct kvm_vcpu *vcpu)
 {
 	if (VALID_PAGE(vcpu->arch.mmu->root_hpa))
-		kvm_x86_ops->load_mmu_pgd(vcpu, vcpu->arch.mmu->root_hpa |
-					        kvm_get_active_pcid(vcpu));
+		kvm_x86_ops.load_mmu_pgd(vcpu, vcpu->arch.mmu->root_hpa |
+					       kvm_get_active_pcid(vcpu));
 }
 
 int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
@@ -170,8 +170,8 @@ static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 				  unsigned pte_access, unsigned pte_pkey,
 				  unsigned pfec)
 {
-	int cpl = kvm_x86_ops->get_cpl(vcpu);
-	unsigned long rflags = kvm_x86_ops->get_rflags(vcpu);
+	int cpl = kvm_x86_ops.get_cpl(vcpu);
+	unsigned long rflags = kvm_x86_ops.get_rflags(vcpu);
 
 	/*
 	 * If CPL < 3, SMAP prevention are disabled if EFLAGS.AC = 1.

arch/x86/kvm/mmu/mmu.c

@@ -305,16 +305,16 @@ kvm_mmu_calc_root_page_role(struct kvm_vcpu *vcpu);
 
 static inline bool kvm_available_flush_tlb_with_range(void)
 {
-	return kvm_x86_ops->tlb_remote_flush_with_range;
+	return kvm_x86_ops.tlb_remote_flush_with_range;
 }
 
 static void kvm_flush_remote_tlbs_with_range(struct kvm *kvm,
 		struct kvm_tlb_range *range)
 {
 	int ret = -ENOTSUPP;
 
-	if (range && kvm_x86_ops->tlb_remote_flush_with_range)
-		ret = kvm_x86_ops->tlb_remote_flush_with_range(kvm, range);
+	if (range && kvm_x86_ops.tlb_remote_flush_with_range)
+		ret = kvm_x86_ops.tlb_remote_flush_with_range(kvm, range);
 
 	if (ret)
 		kvm_flush_remote_tlbs(kvm);
@@ -1642,7 +1642,7 @@ static bool spte_set_dirty(u64 *sptep)
 	rmap_printk("rmap_set_dirty: spte %p %llx\n", sptep, *sptep);
 
 	/*
-	 * Similar to the !kvm_x86_ops->slot_disable_log_dirty case,
+	 * Similar to the !kvm_x86_ops.slot_disable_log_dirty case,
 	 * do not bother adding back write access to pages marked
 	 * SPTE_AD_WRPROT_ONLY_MASK.
 	 */
@@ -1731,8 +1731,8 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
 				struct kvm_memory_slot *slot,
 				gfn_t gfn_offset, unsigned long mask)
 {
-	if (kvm_x86_ops->enable_log_dirty_pt_masked)
-		kvm_x86_ops->enable_log_dirty_pt_masked(kvm, slot, gfn_offset,
+	if (kvm_x86_ops.enable_log_dirty_pt_masked)
+		kvm_x86_ops.enable_log_dirty_pt_masked(kvm, slot, gfn_offset,
 				mask);
 	else
 		kvm_mmu_write_protect_pt_masked(kvm, slot, gfn_offset, mask);
@@ -1747,8 +1747,8 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
  */
 int kvm_arch_write_log_dirty(struct kvm_vcpu *vcpu)
 {
-	if (kvm_x86_ops->write_log_dirty)
-		return kvm_x86_ops->write_log_dirty(vcpu);
+	if (kvm_x86_ops.write_log_dirty)
+		return kvm_x86_ops.write_log_dirty(vcpu);
 
 	return 0;
 }
@@ -3036,7 +3036,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 	if (level > PT_PAGE_TABLE_LEVEL)
 		spte |= PT_PAGE_SIZE_MASK;
 	if (tdp_enabled)
-		spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn,
+		spte |= kvm_x86_ops.get_mt_mask(vcpu, gfn,
 			kvm_is_mmio_pfn(pfn));
 
 	if (host_writable)
@@ -4909,7 +4909,7 @@ kvm_calc_tdp_mmu_root_page_role(struct kvm_vcpu *vcpu, bool base_only)
 	union kvm_mmu_role role = kvm_calc_mmu_role_common(vcpu, base_only);
 
 	role.base.ad_disabled = (shadow_accessed_mask == 0);
-	role.base.level = kvm_x86_ops->get_tdp_level(vcpu);
+	role.base.level = kvm_x86_ops.get_tdp_level(vcpu);
 	role.base.direct = true;
 	role.base.gpte_is_8_bytes = true;
 
@@ -4930,7 +4930,7 @@ static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
 	context->sync_page = nonpaging_sync_page;
 	context->invlpg = nonpaging_invlpg;
 	context->update_pte = nonpaging_update_pte;
-	context->shadow_root_level = kvm_x86_ops->get_tdp_level(vcpu);
+	context->shadow_root_level = kvm_x86_ops.get_tdp_level(vcpu);
 	context->direct_map = true;
 	context->get_guest_pgd = get_cr3;
 	context->get_pdptr = kvm_pdptr_read;
@@ -5183,7 +5183,7 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
 	if (r)
 		goto out;
 	kvm_mmu_load_pgd(vcpu);
-	kvm_x86_ops->tlb_flush(vcpu, true);
+	kvm_x86_ops.tlb_flush(vcpu, true);
 out:
 	return r;
 }
@@ -5488,7 +5488,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
 	 * guest, with the exception of AMD Erratum 1096 which is unrecoverable.
 	 */
 	if (unlikely(insn && !insn_len)) {
-		if (!kvm_x86_ops->need_emulation_on_page_fault(vcpu))
+		if (!kvm_x86_ops.need_emulation_on_page_fault(vcpu))
 			return 1;
 	}
 
@@ -5523,7 +5523,7 @@ void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
 		if (VALID_PAGE(mmu->prev_roots[i].hpa))
 			mmu->invlpg(vcpu, gva, mmu->prev_roots[i].hpa);
 
-	kvm_x86_ops->tlb_flush_gva(vcpu, gva);
+	kvm_x86_ops.tlb_flush_gva(vcpu, gva);
 	++vcpu->stat.invlpg;
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg);
@@ -5548,7 +5548,7 @@ void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid)
 	}
 
 	if (tlb_flush)
-		kvm_x86_ops->tlb_flush_gva(vcpu, gva);
+		kvm_x86_ops.tlb_flush_gva(vcpu, gva);
 
 	++vcpu->stat.invlpg;
 
@@ -5672,7 +5672,7 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
 	 * SVM's 32-bit NPT support, TDP paging doesn't use PAE paging and can
 	 * skip allocating the PDP table.
 	 */
-	if (tdp_enabled && kvm_x86_ops->get_tdp_level(vcpu) > PT32E_ROOT_LEVEL)
+	if (tdp_enabled && kvm_x86_ops.get_tdp_level(vcpu) > PT32E_ROOT_LEVEL)
 		return 0;
 
 	page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_DMA32);