// SPDX-License-Identifier: GPL-2.0-only /* * irq.c: API for in kernel interrupt controller * Copyright (c) 2007, Intel Corporation. * Copyright 2009 Red Hat, Inc. and/or its affiliates. * * Authors: * Yaozu (Eddie) Dong */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include "hyperv.h" #include "ioapic.h" #include "irq.h" #include "trace.h" #include "x86.h" #include "xen.h" /* * check if there are pending timer events * to be processed. */ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) { int r = 0; if (lapic_in_kernel(vcpu)) r = apic_has_pending_timer(vcpu); if (kvm_xen_timer_enabled(vcpu)) r += kvm_xen_has_pending_timer(vcpu); return r; } /* * check if there is a pending userspace external interrupt */ static int pending_userspace_extint(struct kvm_vcpu *v) { return v->arch.pending_external_vector != -1; } static int get_userspace_extint(struct kvm_vcpu *vcpu) { int vector = vcpu->arch.pending_external_vector; vcpu->arch.pending_external_vector = -1; return vector; } /* * check if there is pending interrupt from * non-APIC source without intack. */ int kvm_cpu_has_extint(struct kvm_vcpu *v) { /* * FIXME: interrupt.injected represents an interrupt whose * side-effects have already been applied (e.g. bit from IRR * already moved to ISR). Therefore, it is incorrect to rely * on interrupt.injected to know if there is a pending * interrupt in the user-mode LAPIC. * This leads to nVMX/nSVM not be able to distinguish * if it should exit from L2 to L1 on EXTERNAL_INTERRUPT on * pending interrupt or should re-inject an injected * interrupt. */ if (!lapic_in_kernel(v)) return v->arch.interrupt.injected; if (kvm_xen_has_interrupt(v)) return 1; if (!kvm_apic_accept_pic_intr(v)) return 0; #ifdef CONFIG_KVM_IOAPIC if (pic_in_kernel(v->kvm)) return v->kvm->arch.vpic->output; #endif WARN_ON_ONCE(!irqchip_split(v->kvm)); return pending_userspace_extint(v); } /* * check if there is injectable interrupt: * when virtual interrupt delivery enabled, * interrupt from apic will handled by hardware, * we don't need to check it here. */ int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v) { if (kvm_cpu_has_extint(v)) return 1; if (!is_guest_mode(v) && kvm_vcpu_apicv_active(v)) return 0; return kvm_apic_has_interrupt(v) != -1; /* LAPIC */ } EXPORT_SYMBOL_GPL(kvm_cpu_has_injectable_intr); /* * check if there is pending interrupt without * intack. */ int kvm_cpu_has_interrupt(struct kvm_vcpu *v) { if (kvm_cpu_has_extint(v)) return 1; if (lapic_in_kernel(v) && v->arch.apic->guest_apic_protected) return kvm_x86_call(protected_apic_has_interrupt)(v); return kvm_apic_has_interrupt(v) != -1; /* LAPIC */ } EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt); /* * Read pending interrupt(from non-APIC source) * vector and intack. */ int kvm_cpu_get_extint(struct kvm_vcpu *v) { if (!kvm_cpu_has_extint(v)) { WARN_ON(!lapic_in_kernel(v)); return -1; } if (!lapic_in_kernel(v)) return v->arch.interrupt.nr; #ifdef CONFIG_KVM_XEN if (kvm_xen_has_interrupt(v)) return v->kvm->arch.xen.upcall_vector; #endif #ifdef CONFIG_KVM_IOAPIC if (pic_in_kernel(v->kvm)) return kvm_pic_read_irq(v->kvm); /* PIC */ #endif WARN_ON_ONCE(!irqchip_split(v->kvm)); return get_userspace_extint(v); } EXPORT_SYMBOL_GPL(kvm_cpu_get_extint); /* * Read pending interrupt vector and intack. */ int kvm_cpu_get_interrupt(struct kvm_vcpu *v) { int vector = kvm_cpu_get_extint(v); if (vector != -1) return vector; /* PIC */ vector = kvm_apic_has_interrupt(v); /* APIC */ if (vector != -1) kvm_apic_ack_interrupt(v, vector); return vector; } void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu) { if (lapic_in_kernel(vcpu)) kvm_inject_apic_timer_irqs(vcpu); if (kvm_xen_timer_enabled(vcpu)) kvm_xen_inject_timer_irqs(vcpu); } void __kvm_migrate_timers(struct kvm_vcpu *vcpu) { __kvm_migrate_apic_timer(vcpu); #ifdef CONFIG_KVM_IOAPIC __kvm_migrate_pit_timer(vcpu); #endif kvm_x86_call(migrate_timers)(vcpu); } bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args) { bool resample = args->flags & KVM_IRQFD_FLAG_RESAMPLE; return resample ? irqchip_full(kvm) : irqchip_in_kernel(kvm); } bool kvm_arch_irqchip_in_kernel(struct kvm *kvm) { return irqchip_in_kernel(kvm); } int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src, struct kvm_lapic_irq *irq, struct dest_map *dest_map) { int r = -1; struct kvm_vcpu *vcpu, *lowest = NULL; unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)]; unsigned int dest_vcpus = 0; if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map)) return r; if (irq->dest_mode == APIC_DEST_PHYSICAL && irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) { pr_info("apic: phys broadcast and lowest prio\n"); irq->delivery_mode = APIC_DM_FIXED; } memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap)); kvm_for_each_vcpu(i, vcpu, kvm) { if (!kvm_apic_present(vcpu)) continue; if (!kvm_apic_match_dest(vcpu, src, irq->shorthand, irq->dest_id, irq->dest_mode)) continue; if (!kvm_lowest_prio_delivery(irq)) { if (r < 0) r = 0; r += kvm_apic_set_irq(vcpu, irq, dest_map); } else if (kvm_apic_sw_enabled(vcpu->arch.apic)) { if (!kvm_vector_hashing_enabled()) { if (!lowest) lowest = vcpu; else if (kvm_apic_compare_prio(vcpu, lowest) < 0) lowest = vcpu; } else { __set_bit(i, dest_vcpu_bitmap); dest_vcpus++; } } } if (dest_vcpus != 0) { int idx = kvm_vector_to_index(irq->vector, dest_vcpus, dest_vcpu_bitmap, KVM_MAX_VCPUS); lowest = kvm_get_vcpu(kvm, idx); } if (lowest) r = kvm_apic_set_irq(lowest, irq, dest_map); return r; } static void kvm_msi_to_lapic_irq(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e, struct kvm_lapic_irq *irq) { struct msi_msg msg = { .address_lo = e->msi.address_lo, .address_hi = e->msi.address_hi, .data = e->msi.data }; trace_kvm_msi_set_irq(msg.address_lo | (kvm->arch.x2apic_format ? (u64)msg.address_hi << 32 : 0), msg.data); irq->dest_id = x86_msi_msg_get_destid(&msg, kvm->arch.x2apic_format); irq->vector = msg.arch_data.vector; irq->dest_mode = kvm_lapic_irq_dest_mode(msg.arch_addr_lo.dest_mode_logical); irq->trig_mode = msg.arch_data.is_level; irq->delivery_mode = msg.arch_data.delivery_mode << 8; irq->msi_redir_hint = msg.arch_addr_lo.redirect_hint; irq->level = 1; irq->shorthand = APIC_DEST_NOSHORT; } static inline bool kvm_msi_route_invalid(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e) { return kvm->arch.x2apic_format && (e->msi.address_hi & 0xff); } int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm, int irq_source_id, int level, bool line_status) { struct kvm_lapic_irq irq; if (kvm_msi_route_invalid(kvm, e)) return -EINVAL; if (!level) return -1; kvm_msi_to_lapic_irq(kvm, e, &irq); return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL); } int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm, int irq_source_id, int level, bool line_status) { struct kvm_lapic_irq irq; int r; switch (e->type) { #ifdef CONFIG_KVM_HYPERV case KVM_IRQ_ROUTING_HV_SINT: return kvm_hv_synic_set_irq(e, kvm, irq_source_id, level, line_status); #endif case KVM_IRQ_ROUTING_MSI: if (kvm_msi_route_invalid(kvm, e)) return -EINVAL; kvm_msi_to_lapic_irq(kvm, e, &irq); if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL)) return r; break; #ifdef CONFIG_KVM_XEN case KVM_IRQ_ROUTING_XEN_EVTCHN: if (!level) return -1; return kvm_xen_set_evtchn_fast(&e->xen_evtchn, kvm); #endif default: break; } return -EWOULDBLOCK; } int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event, bool line_status) { if (!irqchip_in_kernel(kvm)) return -ENXIO; irq_event->status = kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID, irq_event->irq, irq_event->level, line_status); return 0; } bool kvm_arch_can_set_irq_routing(struct kvm *kvm) { return irqchip_in_kernel(kvm); } int kvm_set_routing_entry(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e, const struct kvm_irq_routing_entry *ue) { /* We can't check irqchip_in_kernel() here as some callers are * currently initializing the irqchip. Other callers should therefore * check kvm_arch_can_set_irq_routing() before calling this function. */ switch (ue->type) { #ifdef CONFIG_KVM_IOAPIC case KVM_IRQ_ROUTING_IRQCHIP: if (irqchip_split(kvm)) return -EINVAL; e->irqchip.pin = ue->u.irqchip.pin; switch (ue->u.irqchip.irqchip) { case KVM_IRQCHIP_PIC_SLAVE: e->irqchip.pin += PIC_NUM_PINS / 2; fallthrough; case KVM_IRQCHIP_PIC_MASTER: if (ue->u.irqchip.pin >= PIC_NUM_PINS / 2) return -EINVAL; e->set = kvm_pic_set_irq; break; case KVM_IRQCHIP_IOAPIC: if (ue->u.irqchip.pin >= KVM_IOAPIC_NUM_PINS) return -EINVAL; e->set = kvm_ioapic_set_irq; break; default: return -EINVAL; } e->irqchip.irqchip = ue->u.irqchip.irqchip; break; #endif case KVM_IRQ_ROUTING_MSI: e->set = kvm_set_msi; e->msi.address_lo = ue->u.msi.address_lo; e->msi.address_hi = ue->u.msi.address_hi; e->msi.data = ue->u.msi.data; if (kvm_msi_route_invalid(kvm, e)) return -EINVAL; break; #ifdef CONFIG_KVM_HYPERV case KVM_IRQ_ROUTING_HV_SINT: e->set = kvm_hv_synic_set_irq; e->hv_sint.vcpu = ue->u.hv_sint.vcpu; e->hv_sint.sint = ue->u.hv_sint.sint; break; #endif #ifdef CONFIG_KVM_XEN case KVM_IRQ_ROUTING_XEN_EVTCHN: return kvm_xen_setup_evtchn(kvm, e, ue); #endif default: return -EINVAL; } return 0; } bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq, struct kvm_vcpu **dest_vcpu) { int r = 0; unsigned long i; struct kvm_vcpu *vcpu; if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu)) return true; kvm_for_each_vcpu(i, vcpu, kvm) { if (!kvm_apic_present(vcpu)) continue; if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand, irq->dest_id, irq->dest_mode)) continue; if (++r == 2) return false; *dest_vcpu = vcpu; } return r == 1; } EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu); void kvm_scan_ioapic_irq(struct kvm_vcpu *vcpu, u32 dest_id, u16 dest_mode, u8 vector, unsigned long *ioapic_handled_vectors) { /* * Intercept EOI if the vCPU is the target of the new IRQ routing, or * the vCPU has a pending IRQ from the old routing, i.e. if the vCPU * may receive a level-triggered IRQ in the future, or already received * level-triggered IRQ. The EOI needs to be intercepted and forwarded * to I/O APIC emulation so that the IRQ can be de-asserted. */ if (kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT, dest_id, dest_mode)) { __set_bit(vector, ioapic_handled_vectors); } else if (kvm_apic_pending_eoi(vcpu, vector)) { __set_bit(vector, ioapic_handled_vectors); /* * Track the highest pending EOI for which the vCPU is NOT the * target in the new routing. Only the EOI for the IRQ that is * in-flight (for the old routing) needs to be intercepted, any * future IRQs that arrive on this vCPU will be coincidental to * the level-triggered routing and don't need to be intercepted. */ if ((int)vector > vcpu->arch.highest_stale_pending_ioapic_eoi) vcpu->arch.highest_stale_pending_ioapic_eoi = vector; } } void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, ulong *ioapic_handled_vectors) { struct kvm *kvm = vcpu->kvm; struct kvm_kernel_irq_routing_entry *entry; struct kvm_irq_routing_table *table; u32 i, nr_ioapic_pins; int idx; idx = srcu_read_lock(&kvm->irq_srcu); table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu); nr_ioapic_pins = min_t(u32, table->nr_rt_entries, kvm->arch.nr_reserved_ioapic_pins); for (i = 0; i < nr_ioapic_pins; ++i) { hlist_for_each_entry(entry, &table->map[i], link) { struct kvm_lapic_irq irq; if (entry->type != KVM_IRQ_ROUTING_MSI) continue; kvm_msi_to_lapic_irq(vcpu->kvm, entry, &irq); if (!irq.trig_mode) continue; kvm_scan_ioapic_irq(vcpu, irq.dest_id, irq.dest_mode, irq.vector, ioapic_handled_vectors); } } srcu_read_unlock(&kvm->irq_srcu, idx); } void kvm_arch_irq_routing_update(struct kvm *kvm) { #ifdef CONFIG_KVM_HYPERV kvm_hv_irq_routing_update(kvm); #endif if (irqchip_split(kvm)) kvm_make_scan_ioapic_request(kvm); } static int kvm_pi_update_irte(struct kvm_kernel_irqfd *irqfd, struct kvm_kernel_irq_routing_entry *entry) { unsigned int host_irq = irqfd->producer->irq; struct kvm *kvm = irqfd->kvm; struct kvm_vcpu *vcpu = NULL; struct kvm_lapic_irq irq; int r; if (WARN_ON_ONCE(!irqchip_in_kernel(kvm) || !kvm_arch_has_irq_bypass())) return -EINVAL; if (entry && entry->type == KVM_IRQ_ROUTING_MSI) { kvm_msi_to_lapic_irq(kvm, entry, &irq); /* * Force remapped mode if hardware doesn't support posting the * virtual interrupt to a vCPU. Only IRQs are postable (NMIs, * SMIs, etc. are not), and neither AMD nor Intel IOMMUs support * posting multicast/broadcast IRQs. If the interrupt can't be * posted, the device MSI needs to be routed to the host so that * the guest's desired interrupt can be synthesized by KVM. * * This means that KVM can only post lowest-priority interrupts * if they have a single CPU as the destination, e.g. only if * the guest has affined the interrupt to a single vCPU. */ if (!kvm_intr_is_single_vcpu(kvm, &irq, &vcpu) || !kvm_irq_is_postable(&irq)) vcpu = NULL; } if (!irqfd->irq_bypass_vcpu && !vcpu) return 0; r = kvm_x86_call(pi_update_irte)(irqfd, irqfd->kvm, host_irq, irqfd->gsi, vcpu, irq.vector); if (r) { WARN_ON_ONCE(irqfd->irq_bypass_vcpu && !vcpu); irqfd->irq_bypass_vcpu = NULL; return r; } irqfd->irq_bypass_vcpu = vcpu; trace_kvm_pi_irte_update(host_irq, vcpu, irqfd->gsi, irq.vector, !!vcpu); return 0; } int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, struct irq_bypass_producer *prod) { struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); struct kvm *kvm = irqfd->kvm; int ret = 0; spin_lock_irq(&kvm->irqfds.lock); irqfd->producer = prod; if (!kvm->arch.nr_possible_bypass_irqs++) kvm_x86_call(pi_start_bypass)(kvm); if (irqfd->irq_entry.type == KVM_IRQ_ROUTING_MSI) { ret = kvm_pi_update_irte(irqfd, &irqfd->irq_entry); if (ret) kvm->arch.nr_possible_bypass_irqs--; } spin_unlock_irq(&kvm->irqfds.lock); return ret; } void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, struct irq_bypass_producer *prod) { struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); struct kvm *kvm = irqfd->kvm; int ret; WARN_ON(irqfd->producer != prod); /* * If the producer of an IRQ that is currently being posted to a vCPU * is unregistered, change the associated IRTE back to remapped mode as * the IRQ has been released (or repurposed) by the device driver, i.e. * KVM must relinquish control of the IRTE. */ spin_lock_irq(&kvm->irqfds.lock); if (irqfd->irq_entry.type == KVM_IRQ_ROUTING_MSI) { ret = kvm_pi_update_irte(irqfd, NULL); if (ret) pr_info("irq bypass consumer (eventfd %p) unregistration fails: %d\n", irqfd->consumer.eventfd, ret); } irqfd->producer = NULL; kvm->arch.nr_possible_bypass_irqs--; spin_unlock_irq(&kvm->irqfds.lock); } void kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd, struct kvm_kernel_irq_routing_entry *old, struct kvm_kernel_irq_routing_entry *new) { if (new->type != KVM_IRQ_ROUTING_MSI && old->type != KVM_IRQ_ROUTING_MSI) return; if (old->type == KVM_IRQ_ROUTING_MSI && new->type == KVM_IRQ_ROUTING_MSI && !memcmp(&old->msi, &new->msi, sizeof(new->msi))) return; kvm_pi_update_irte(irqfd, new); } #ifdef CONFIG_KVM_IOAPIC #define IOAPIC_ROUTING_ENTRY(irq) \ { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \ .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } } #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq) #define PIC_ROUTING_ENTRY(irq) \ { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \ .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } } #define ROUTING_ENTRY2(irq) \ IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq) static const struct kvm_irq_routing_entry default_routing[] = { ROUTING_ENTRY2(0), ROUTING_ENTRY2(1), ROUTING_ENTRY2(2), ROUTING_ENTRY2(3), ROUTING_ENTRY2(4), ROUTING_ENTRY2(5), ROUTING_ENTRY2(6), ROUTING_ENTRY2(7), ROUTING_ENTRY2(8), ROUTING_ENTRY2(9), ROUTING_ENTRY2(10), ROUTING_ENTRY2(11), ROUTING_ENTRY2(12), ROUTING_ENTRY2(13), ROUTING_ENTRY2(14), ROUTING_ENTRY2(15), ROUTING_ENTRY1(16), ROUTING_ENTRY1(17), ROUTING_ENTRY1(18), ROUTING_ENTRY1(19), ROUTING_ENTRY1(20), ROUTING_ENTRY1(21), ROUTING_ENTRY1(22), ROUTING_ENTRY1(23), }; int kvm_setup_default_ioapic_and_pic_routing(struct kvm *kvm) { return kvm_set_irq_routing(kvm, default_routing, ARRAY_SIZE(default_routing), 0); } int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip) { struct kvm_pic *pic = kvm->arch.vpic; int r; r = 0; switch (chip->chip_id) { case KVM_IRQCHIP_PIC_MASTER: memcpy(&chip->chip.pic, &pic->pics[0], sizeof(struct kvm_pic_state)); break; case KVM_IRQCHIP_PIC_SLAVE: memcpy(&chip->chip.pic, &pic->pics[1], sizeof(struct kvm_pic_state)); break; case KVM_IRQCHIP_IOAPIC: kvm_get_ioapic(kvm, &chip->chip.ioapic); break; default: r = -EINVAL; break; } return r; } int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip) { struct kvm_pic *pic = kvm->arch.vpic; int r; r = 0; switch (chip->chip_id) { case KVM_IRQCHIP_PIC_MASTER: spin_lock(&pic->lock); memcpy(&pic->pics[0], &chip->chip.pic, sizeof(struct kvm_pic_state)); spin_unlock(&pic->lock); break; case KVM_IRQCHIP_PIC_SLAVE: spin_lock(&pic->lock); memcpy(&pic->pics[1], &chip->chip.pic, sizeof(struct kvm_pic_state)); spin_unlock(&pic->lock); break; case KVM_IRQCHIP_IOAPIC: kvm_set_ioapic(kvm, &chip->chip.ioapic); break; default: r = -EINVAL; break; } kvm_pic_update_irq(pic); return r; } #endif