[RFC PATCH v1 41/42] kvm: x86: finalize per-plane APIC state and CPUID placement

[Sriram Nambakam <snambakam@linux.microsoft.com>]

Adopt the vm-planes-merged design for x86 plane state: keep CPUID and
cpu_caps in kvm_vcpu_arch_common, make apic_map and APICv-inhibit
tracking VM-scoped again, and drop the superseded intermediate fields
(planes_share_fpu, irr_pending_planes, kvm_arch_plane.apicv_inhibit_reasons,
kvm_lapic_irq.plane). These changes originated in merge-commit conflict
resolutions that a --no-merges linearization could not carry over.
---
 arch/x86/include/asm/kvm_host.h | 36 +++++-----------------
 arch/x86/kvm/cpuid.c            | 19 +-----------
 arch/x86/kvm/hyperv.c           |  1 -
 arch/x86/kvm/i8254.c            |  4 +--
 arch/x86/kvm/lapic.c            | 53 +++++++--------------------------
 arch/x86/kvm/xen.c              |  1 -
 6 files changed, 20 insertions(+), 94 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index bbccb9d3d801..b1a7e4ca8870 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -956,12 +956,6 @@ struct kvm_vcpu_arch {
 	u64 ia32_xss;
 	u64 guest_supported_xss;
 
-	/*
-	 * Only valid in plane0.  The bitmask of planes that received
-	 * an interrupt, to be checked against req_exit_planes.
-	 */
-	atomic_t irr_pending_planes;
-
 	struct kvm_pio_request pio;
 	void *pio_data;
 	void *sev_pio_data;
@@ -1175,10 +1169,6 @@ struct kvm_arch_memory_slot {
 	unsigned short *gfn_write_track;
 };
 
-struct kvm_arch_plane {
-	unsigned long apicv_inhibit_reasons;
-};
-
 /*
  * Track the mode of the optimized logical map, as the rules for decoding the
  * destination vary per mode.  Enabling the optimized logical map requires all
@@ -1397,13 +1387,11 @@ enum kvm_apicv_inhibit {
 	/*
 	 * PIT (i8254) 're-inject' mode, relies on EOI intercept,
 	 * which AVIC doesn't support for edge triggered interrupts.
-	 * Applied only to plane 0.
 	 */
 	APICV_INHIBIT_REASON_PIT_REINJ,
 
 	/*
-	 * AVIC is disabled because SEV doesn't support it.  Sticky and applied
-	 * only to plane 0.
+	 * AVIC is disabled because SEV doesn't support it.
 	 */
 	APICV_INHIBIT_REASON_SEV,
 
@@ -1483,7 +1471,6 @@ struct kvm_arch {
 	unsigned int indirect_shadow_pages;
 	u8 mmu_valid_gen;
 	u8 vm_type;
-	bool planes_share_fpu;
 	bool has_private_mem;
 	bool has_protected_state;
 	bool has_protected_eoi;
@@ -1805,7 +1792,6 @@ struct kvm_lapic_irq {
 	u16 delivery_mode;
 	u16 dest_mode;
 	bool level;
-	u8 plane;
 	u16 trig_mode;
 	u32 shorthand;
 	u32 dest_id;
@@ -2399,21 +2385,21 @@ gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva,
 bool kvm_apicv_activated(struct kvm *kvm);
 bool kvm_vcpu_apicv_activated(struct kvm_vcpu *vcpu);
 void __kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu);
-void __kvm_set_or_clear_apicv_inhibit(struct kvm_plane *plane,
+void __kvm_set_or_clear_apicv_inhibit(struct kvm *kvm,
 				      enum kvm_apicv_inhibit reason, bool set);
-void kvm_set_or_clear_apicv_inhibit(struct kvm_plane *plane,
+void kvm_set_or_clear_apicv_inhibit(struct kvm *kvm,
 				    enum kvm_apicv_inhibit reason, bool set);
 
-static inline void kvm_set_apicv_inhibit(struct kvm_plane *plane,
+static inline void kvm_set_apicv_inhibit(struct kvm *kvm,
 					 enum kvm_apicv_inhibit reason)
 {
-	kvm_set_or_clear_apicv_inhibit(plane, reason, true);
+	kvm_set_or_clear_apicv_inhibit(kvm, reason, true);
 }
 
-static inline void kvm_clear_apicv_inhibit(struct kvm_plane *plane,
+static inline void kvm_clear_apicv_inhibit(struct kvm *kvm,
 					   enum kvm_apicv_inhibit reason)
 {
-	kvm_set_or_clear_apicv_inhibit(plane, reason, false);
+	kvm_set_or_clear_apicv_inhibit(kvm, reason, false);
 }
 
 void kvm_inc_or_dec_irq_window_inhibit(struct kvm *kvm, bool inc);
@@ -2503,8 +2489,6 @@ enum {
 # define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, 0)
 #endif
 
-#define KVM_MAX_VCPU_PLANES	16
-
 int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v);
 int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu);
 int kvm_cpu_has_extint(struct kvm_vcpu *v);
@@ -2539,9 +2523,6 @@ void kvm_make_scan_ioapic_request(struct kvm *kvm);
 void kvm_make_scan_ioapic_request_mask(struct kvm *kvm,
 				       unsigned long *vcpu_bitmap);
 
-void kvm_arch_init_plane(struct kvm_plane *plane);
-void kvm_arch_free_plane(struct kvm_plane *plane);
-
 bool kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu,
 				     struct kvm_async_pf *work);
 void kvm_arch_async_page_present(struct kvm_vcpu *vcpu,
@@ -2612,7 +2593,4 @@ static inline bool kvm_arch_has_irq_bypass(void)
 	return enable_device_posted_irqs;
 }
 
-int kvm_arch_nr_vcpu_planes(struct kvm *kvm);
-bool kvm_arch_planes_share_fpu(struct kvm *kvm);
-
 #endif /* _ASM_X86_KVM_HOST_H */
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index ce337c6d3bcf..7b8cd379ba9f 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -555,7 +555,7 @@ static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2,
 	 * KVM_SET_CPUID{,2} again. To support this legacy behavior, check
 	 * whether the supplied CPUID data is equal to what's already set.
 	 */
-	if (!kvm_can_set_cpuid_and_feature_msrs(vcpu) || vcpu->has_planes) {
+	if (!kvm_can_set_cpuid_and_feature_msrs(vcpu)) {
 		r = kvm_cpuid_check_equal(vcpu, e2, nent);
 		if (r)
 			goto err;
@@ -594,23 +594,6 @@ static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2,
 	return r;
 }
 
-int kvm_dup_cpuid(struct kvm_vcpu *vcpu, struct kvm_vcpu *source)
-{
-	if (WARN_ON_ONCE(vcpu->arch.cpuid_entries || vcpu->arch.cpuid_nent))
-		return -EEXIST;
-
-	vcpu->arch.cpuid_entries = kmemdup(source->arch.cpuid_entries,
-		     source->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2),
-		     GFP_KERNEL_ACCOUNT);
-	if (!vcpu->arch.cpuid_entries)
-		return -ENOMEM;
-
-	memcpy(vcpu->arch.cpu_caps, source->arch.cpu_caps, sizeof(source->arch.cpu_caps));
-	vcpu->arch.cpuid_nent = source->arch.cpuid_nent;
-
-	return 0;
-}
-
 /* when an old userspace process fills a new kernel module */
 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
 			     struct kvm_cpuid *cpuid,
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 8ef09b8125b7..ee6b32d2a5cb 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -491,7 +491,6 @@ static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 	irq.delivery_mode = APIC_DM_FIXED;
 	irq.vector = vector;
 	irq.level = 1;
-
 	ret = kvm_irq_delivery_to_apic(vcpu->plane, vcpu->arch.apic, &irq);
 	trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 	return ret;
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index cd47fd88c9f7..bfe590378bd2 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -305,13 +305,13 @@ static void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject)
 	 * So, deactivate APICv when PIT is in reinject mode.
 	 */
 	if (reinject) {
-		kvm_set_apicv_inhibit(kvm->planes[0], APICV_INHIBIT_REASON_PIT_REINJ);
+		kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PIT_REINJ);
 		/* The initial state is preserved while ps->reinject == 0. */
 		kvm_pit_reset_reinject(pit);
 		kvm_register_irq_ack_notifier(kvm, &ps->irq_ack_notifier);
 		kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
 	} else {
-		kvm_clear_apicv_inhibit(kvm->planes[0], APICV_INHIBIT_REASON_PIT_REINJ);
+		kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PIT_REINJ);
 		kvm_unregister_irq_ack_notifier(kvm, &ps->irq_ack_notifier);
 		kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
 	}
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 4cca1ea6a16e..ff923133a834 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -405,7 +405,6 @@ enum {
 
 static void kvm_recalculate_apic_map(struct kvm_plane *plane)
 {
-	struct kvm_plane *plane = kvm->planes[0];
 	struct kvm_apic_map *new, *old = NULL;
 	struct kvm *kvm = plane->kvm;
 	struct kvm_vcpu *vcpu;
@@ -486,19 +485,19 @@ static void kvm_recalculate_apic_map(struct kvm_plane *plane)
 	 * map also applies to APICv.
 	 */
 	if (!new)
-		kvm_set_apicv_inhibit(plane, APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED);
+		kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED);
 	else
-		kvm_clear_apicv_inhibit(plane, APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED);
+		kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED);
 
 	if (!new || new->logical_mode == KVM_APIC_MODE_MAP_DISABLED)
-		kvm_set_apicv_inhibit(plane, APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED);
+		kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED);
 	else
-		kvm_clear_apicv_inhibit(plane, APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED);
+		kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED);
 
 	if (xapic_id_mismatch)
-		kvm_set_apicv_inhibit(plane, APICV_INHIBIT_REASON_APIC_ID_MODIFIED);
+		kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_APIC_ID_MODIFIED);
 	else
-		kvm_clear_apicv_inhibit(plane, APICV_INHIBIT_REASON_APIC_ID_MODIFIED);
+		kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_APIC_ID_MODIFIED);
 
 	old = rcu_dereference_protected(plane->arch.apic_map,
 			lockdep_is_held(&plane->arch.apic_map_lock));
@@ -1396,39 +1395,6 @@ int __kvm_irq_delivery_to_apic(struct kvm_plane *plane, struct kvm_lapic *src,
 	return r;
 }
 
-static void kvm_lapic_deliver_interrupt(struct kvm_vcpu *vcpu, struct kvm_lapic *apic,
-					int delivery_mode, int trig_mode, int vector)
-{
-	struct kvm_vcpu *plane0_vcpu = vcpu->plane0;
-	struct kvm_plane *running_plane;
-	u16 req_exit_planes;
-
-	kvm_x86_call(deliver_interrupt)(apic, delivery_mode, trig_mode, vector);
-
-	/*
-	 * test_and_set_bit implies a memory barrier, so IRR is written before
-	 * reading irr_pending_planes below...
-	 */
-	if (!test_and_set_bit(vcpu->plane, &plane0_vcpu->arch.irr_pending_planes)) {
-		/*
-		 * ... and also running_plane and req_exit_planes are read after writing
-		 * irr_pending_planes.  Both barriers pair with kvm_arch_vcpu_ioctl_run().
-		 */
-		smp_mb__after_atomic();
-
-		running_plane = READ_ONCE(plane0_vcpu->running_plane);
-		if (!running_plane)
-			return;
-
-		req_exit_planes = READ_ONCE(plane0_vcpu->req_exit_planes);
-		if (!(req_exit_planes & BIT(vcpu->plane)))
-			return;
-
-		kvm_make_request(KVM_REQ_PLANE_INTERRUPT,
-				 kvm_get_plane_vcpu(running_plane, vcpu->vcpu_id));
-	}
-}
-
 /*
  * Add a pending IRQ into lapic.
  * Return 1 if successfully added and 0 if discarded.
@@ -1470,7 +1436,8 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
 				apic_clear_vector(vector, apic->regs + APIC_TMR);
 		}
 
-		kvm_lapic_deliver_interrupt(vcpu, apic, delivery_mode, trig_mode, vector);
+		kvm_x86_call(deliver_interrupt)(apic, delivery_mode,
+						trig_mode, vector);
 		break;
 
 	case APIC_DM_REMRD:
@@ -2087,7 +2054,7 @@ static void apic_timer_expired(struct kvm_lapic *apic, bool from_timer_fn)
 	if (apic_lvtt_tscdeadline(apic) || ktimer->hv_timer_in_use)
 		ktimer->expired_tscdeadline = ktimer->tscdeadline;
 
-	if (!from_timer_fn && apic->apicv_active && vcpu->wants_to_run) {
+	if (!from_timer_fn && apic->apicv_active && kvm_vcpu_wants_to_run(vcpu)) {
 		WARN_ON(kvm_get_running_vcpu() != vcpu);
 		kvm_apic_inject_pending_timer_irqs(apic);
 		return;
@@ -2867,7 +2834,7 @@ static void __kvm_apic_set_base(struct kvm_vcpu *vcpu, u64 value)
 
 	if ((value & MSR_IA32_APICBASE_ENABLE) &&
 	     apic->base_address != APIC_DEFAULT_PHYS_BASE) {
-		kvm_set_apicv_inhibit(vcpu_to_plane(vcpu),
+		kvm_set_apicv_inhibit(apic->vcpu->kvm,
 				      APICV_INHIBIT_REASON_APIC_BASE_MODIFIED);
 	}
 }
diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index 399406752108..4527f04c6617 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -625,7 +625,6 @@ void kvm_xen_inject_vcpu_vector(struct kvm_vcpu *v)
 	irq.shorthand = APIC_DEST_NOSHORT;
 	irq.delivery_mode = APIC_DM_FIXED;
 	irq.level = 1;
-
 	kvm_irq_delivery_to_apic(v->plane, NULL, &irq);
 }
 
-- 
2.55.0