diff options
Diffstat (limited to 'arch/x86/kvm/irq.c')
-rw-r--r-- | arch/x86/kvm/irq.c | 563 |
1 files changed, 552 insertions, 11 deletions
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c index 63f66c51975a..16da89259011 100644 --- a/arch/x86/kvm/irq.c +++ b/arch/x86/kvm/irq.c @@ -11,9 +11,12 @@ #include <linux/export.h> #include <linux/kvm_host.h> +#include <linux/kvm_irqfd.h> +#include "hyperv.h" +#include "ioapic.h" #include "irq.h" -#include "i8254.h" +#include "trace.h" #include "x86.h" #include "xen.h" @@ -41,6 +44,14 @@ 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. @@ -67,10 +78,13 @@ int kvm_cpu_has_extint(struct kvm_vcpu *v) if (!kvm_apic_accept_pic_intr(v)) return 0; - if (irqchip_split(v->kvm)) - return pending_userspace_extint(v); - else +#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); } /* @@ -100,6 +114,9 @@ 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); @@ -123,13 +140,13 @@ int kvm_cpu_get_extint(struct kvm_vcpu *v) return v->kvm->arch.xen.upcall_vector; #endif - if (irqchip_split(v->kvm)) { - int vector = v->arch.pending_external_vector; - - v->arch.pending_external_vector = -1; - return vector; - } else +#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); @@ -160,7 +177,9 @@ void kvm_inject_pending_timer_irqs(struct kvm_vcpu *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); } @@ -168,10 +187,532 @@ bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args) { bool resample = args->flags & KVM_IRQFD_FLAG_RESAMPLE; - return resample ? irqchip_kernel(kvm) : irqchip_in_kernel(kvm); + 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 |