| /* |
| * Xen event channels |
| * |
| * Xen models interrupts with abstract event channels. Because each |
| * domain gets 1024 event channels, but NR_IRQ is not that large, we |
| * must dynamically map irqs<->event channels. The event channels |
| * interface with the rest of the kernel by defining a xen interrupt |
| * chip. When an event is recieved, it is mapped to an irq and sent |
| * through the normal interrupt processing path. |
| * |
| * There are four kinds of events which can be mapped to an event |
| * channel: |
| * |
| * 1. Inter-domain notifications. This includes all the virtual |
| * device events, since they're driven by front-ends in another domain |
| * (typically dom0). |
| * 2. VIRQs, typically used for timers. These are per-cpu events. |
| * 3. IPIs. |
| * 4. PIRQs - Hardware interrupts. |
| * |
| * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 |
| */ |
| |
| #include <linux/linkage.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/module.h> |
| #include <linux/string.h> |
| #include <linux/bootmem.h> |
| #include <linux/slab.h> |
| #include <linux/irqnr.h> |
| |
| #include <asm/desc.h> |
| #include <asm/ptrace.h> |
| #include <asm/irq.h> |
| #include <asm/idle.h> |
| #include <asm/io_apic.h> |
| #include <asm/sync_bitops.h> |
| #include <asm/xen/hypercall.h> |
| #include <asm/xen/hypervisor.h> |
| |
| #include <xen/xen.h> |
| #include <xen/hvm.h> |
| #include <xen/xen-ops.h> |
| #include <xen/events.h> |
| #include <xen/interface/xen.h> |
| #include <xen/interface/event_channel.h> |
| #include <xen/interface/hvm/hvm_op.h> |
| #include <xen/interface/hvm/params.h> |
| |
| /* |
| * This lock protects updates to the following mapping and reference-count |
| * arrays. The lock does not need to be acquired to read the mapping tables. |
| */ |
| static DEFINE_SPINLOCK(irq_mapping_update_lock); |
| |
| /* IRQ <-> VIRQ mapping. */ |
| static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1}; |
| |
| /* IRQ <-> IPI mapping */ |
| static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1}; |
| |
| /* Interrupt types. */ |
| enum xen_irq_type { |
| IRQT_UNBOUND = 0, |
| IRQT_PIRQ, |
| IRQT_VIRQ, |
| IRQT_IPI, |
| IRQT_EVTCHN |
| }; |
| |
| /* |
| * Packed IRQ information: |
| * type - enum xen_irq_type |
| * event channel - irq->event channel mapping |
| * cpu - cpu this event channel is bound to |
| * index - type-specific information: |
| * PIRQ - vector, with MSB being "needs EIO" |
| * VIRQ - virq number |
| * IPI - IPI vector |
| * EVTCHN - |
| */ |
| struct irq_info |
| { |
| enum xen_irq_type type; /* type */ |
| unsigned short evtchn; /* event channel */ |
| unsigned short cpu; /* cpu bound */ |
| |
| union { |
| unsigned short virq; |
| enum ipi_vector ipi; |
| struct { |
| unsigned short gsi; |
| unsigned char vector; |
| unsigned char flags; |
| } pirq; |
| } u; |
| }; |
| #define PIRQ_NEEDS_EOI (1 << 0) |
| #define PIRQ_SHAREABLE (1 << 1) |
| |
| static struct irq_info *irq_info; |
| |
| static int *evtchn_to_irq; |
| struct cpu_evtchn_s { |
| unsigned long bits[NR_EVENT_CHANNELS/BITS_PER_LONG]; |
| }; |
| |
| static __initdata struct cpu_evtchn_s init_evtchn_mask = { |
| .bits[0 ... (NR_EVENT_CHANNELS/BITS_PER_LONG)-1] = ~0ul, |
| }; |
| static struct cpu_evtchn_s *cpu_evtchn_mask_p = &init_evtchn_mask; |
| |
| static inline unsigned long *cpu_evtchn_mask(int cpu) |
| { |
| return cpu_evtchn_mask_p[cpu].bits; |
| } |
| |
| /* Xen will never allocate port zero for any purpose. */ |
| #define VALID_EVTCHN(chn) ((chn) != 0) |
| |
| static struct irq_chip xen_dynamic_chip; |
| static struct irq_chip xen_percpu_chip; |
| static struct irq_chip xen_pirq_chip; |
| |
| /* Constructor for packed IRQ information. */ |
| static struct irq_info mk_unbound_info(void) |
| { |
| return (struct irq_info) { .type = IRQT_UNBOUND }; |
| } |
| |
| static struct irq_info mk_evtchn_info(unsigned short evtchn) |
| { |
| return (struct irq_info) { .type = IRQT_EVTCHN, .evtchn = evtchn, |
| .cpu = 0 }; |
| } |
| |
| static struct irq_info mk_ipi_info(unsigned short evtchn, enum ipi_vector ipi) |
| { |
| return (struct irq_info) { .type = IRQT_IPI, .evtchn = evtchn, |
| .cpu = 0, .u.ipi = ipi }; |
| } |
| |
| static struct irq_info mk_virq_info(unsigned short evtchn, unsigned short virq) |
| { |
| return (struct irq_info) { .type = IRQT_VIRQ, .evtchn = evtchn, |
| .cpu = 0, .u.virq = virq }; |
| } |
| |
| static struct irq_info mk_pirq_info(unsigned short evtchn, |
| unsigned short gsi, unsigned short vector) |
| { |
| return (struct irq_info) { .type = IRQT_PIRQ, .evtchn = evtchn, |
| .cpu = 0, .u.pirq = { .gsi = gsi, .vector = vector } }; |
| } |
| |
| /* |
| * Accessors for packed IRQ information. |
| */ |
| static struct irq_info *info_for_irq(unsigned irq) |
| { |
| return &irq_info[irq]; |
| } |
| |
| static unsigned int evtchn_from_irq(unsigned irq) |
| { |
| return info_for_irq(irq)->evtchn; |
| } |
| |
| unsigned irq_from_evtchn(unsigned int evtchn) |
| { |
| return evtchn_to_irq[evtchn]; |
| } |
| EXPORT_SYMBOL_GPL(irq_from_evtchn); |
| |
| static enum ipi_vector ipi_from_irq(unsigned irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| BUG_ON(info == NULL); |
| BUG_ON(info->type != IRQT_IPI); |
| |
| return info->u.ipi; |
| } |
| |
| static unsigned virq_from_irq(unsigned irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| BUG_ON(info == NULL); |
| BUG_ON(info->type != IRQT_VIRQ); |
| |
| return info->u.virq; |
| } |
| |
| static unsigned gsi_from_irq(unsigned irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| BUG_ON(info == NULL); |
| BUG_ON(info->type != IRQT_PIRQ); |
| |
| return info->u.pirq.gsi; |
| } |
| |
| static unsigned vector_from_irq(unsigned irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| BUG_ON(info == NULL); |
| BUG_ON(info->type != IRQT_PIRQ); |
| |
| return info->u.pirq.vector; |
| } |
| |
| static enum xen_irq_type type_from_irq(unsigned irq) |
| { |
| return info_for_irq(irq)->type; |
| } |
| |
| static unsigned cpu_from_irq(unsigned irq) |
| { |
| return info_for_irq(irq)->cpu; |
| } |
| |
| static unsigned int cpu_from_evtchn(unsigned int evtchn) |
| { |
| int irq = evtchn_to_irq[evtchn]; |
| unsigned ret = 0; |
| |
| if (irq != -1) |
| ret = cpu_from_irq(irq); |
| |
| return ret; |
| } |
| |
| static bool pirq_needs_eoi(unsigned irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| BUG_ON(info->type != IRQT_PIRQ); |
| |
| return info->u.pirq.flags & PIRQ_NEEDS_EOI; |
| } |
| |
| static inline unsigned long active_evtchns(unsigned int cpu, |
| struct shared_info *sh, |
| unsigned int idx) |
| { |
| return (sh->evtchn_pending[idx] & |
| cpu_evtchn_mask(cpu)[idx] & |
| ~sh->evtchn_mask[idx]); |
| } |
| |
| static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu) |
| { |
| int irq = evtchn_to_irq[chn]; |
| |
| BUG_ON(irq == -1); |
| #ifdef CONFIG_SMP |
| cpumask_copy(irq_to_desc(irq)->affinity, cpumask_of(cpu)); |
| #endif |
| |
| __clear_bit(chn, cpu_evtchn_mask(cpu_from_irq(irq))); |
| __set_bit(chn, cpu_evtchn_mask(cpu)); |
| |
| irq_info[irq].cpu = cpu; |
| } |
| |
| static void init_evtchn_cpu_bindings(void) |
| { |
| #ifdef CONFIG_SMP |
| struct irq_desc *desc; |
| int i; |
| |
| /* By default all event channels notify CPU#0. */ |
| for_each_irq_desc(i, desc) { |
| cpumask_copy(desc->affinity, cpumask_of(0)); |
| } |
| #endif |
| |
| memset(cpu_evtchn_mask(0), ~0, sizeof(cpu_evtchn_mask(0))); |
| } |
| |
| static inline void clear_evtchn(int port) |
| { |
| struct shared_info *s = HYPERVISOR_shared_info; |
| sync_clear_bit(port, &s->evtchn_pending[0]); |
| } |
| |
| static inline void set_evtchn(int port) |
| { |
| struct shared_info *s = HYPERVISOR_shared_info; |
| sync_set_bit(port, &s->evtchn_pending[0]); |
| } |
| |
| static inline int test_evtchn(int port) |
| { |
| struct shared_info *s = HYPERVISOR_shared_info; |
| return sync_test_bit(port, &s->evtchn_pending[0]); |
| } |
| |
| |
| /** |
| * notify_remote_via_irq - send event to remote end of event channel via irq |
| * @irq: irq of event channel to send event to |
| * |
| * Unlike notify_remote_via_evtchn(), this is safe to use across |
| * save/restore. Notifications on a broken connection are silently |
| * dropped. |
| */ |
| void notify_remote_via_irq(int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| notify_remote_via_evtchn(evtchn); |
| } |
| EXPORT_SYMBOL_GPL(notify_remote_via_irq); |
| |
| static void mask_evtchn(int port) |
| { |
| struct shared_info *s = HYPERVISOR_shared_info; |
| sync_set_bit(port, &s->evtchn_mask[0]); |
| } |
| |
| static void unmask_evtchn(int port) |
| { |
| struct shared_info *s = HYPERVISOR_shared_info; |
| unsigned int cpu = get_cpu(); |
| |
| BUG_ON(!irqs_disabled()); |
| |
| /* Slow path (hypercall) if this is a non-local port. */ |
| if (unlikely(cpu != cpu_from_evtchn(port))) { |
| struct evtchn_unmask unmask = { .port = port }; |
| (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask); |
| } else { |
| struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu); |
| |
| sync_clear_bit(port, &s->evtchn_mask[0]); |
| |
| /* |
| * The following is basically the equivalent of |
| * 'hw_resend_irq'. Just like a real IO-APIC we 'lose |
| * the interrupt edge' if the channel is masked. |
| */ |
| if (sync_test_bit(port, &s->evtchn_pending[0]) && |
| !sync_test_and_set_bit(port / BITS_PER_LONG, |
| &vcpu_info->evtchn_pending_sel)) |
| vcpu_info->evtchn_upcall_pending = 1; |
| } |
| |
| put_cpu(); |
| } |
| |
| static int get_nr_hw_irqs(void) |
| { |
| int ret = 1; |
| |
| #ifdef CONFIG_X86_IO_APIC |
| ret = get_nr_irqs_gsi(); |
| #endif |
| |
| return ret; |
| } |
| |
| static int find_unbound_irq(void) |
| { |
| struct irq_data *data; |
| int irq, res; |
| int start = get_nr_hw_irqs(); |
| |
| if (start == nr_irqs) |
| goto no_irqs; |
| |
| /* nr_irqs is a magic value. Must not use it.*/ |
| for (irq = nr_irqs-1; irq > start; irq--) { |
| data = irq_get_irq_data(irq); |
| /* only 0->15 have init'd desc; handle irq > 16 */ |
| if (!data) |
| break; |
| if (data->chip == &no_irq_chip) |
| break; |
| if (data->chip != &xen_dynamic_chip) |
| continue; |
| if (irq_info[irq].type == IRQT_UNBOUND) |
| return irq; |
| } |
| |
| if (irq == start) |
| goto no_irqs; |
| |
| res = irq_alloc_desc_at(irq, 0); |
| |
| if (WARN_ON(res != irq)) |
| return -1; |
| |
| return irq; |
| |
| no_irqs: |
| panic("No available IRQ to bind to: increase nr_irqs!\n"); |
| } |
| |
| static bool identity_mapped_irq(unsigned irq) |
| { |
| /* identity map all the hardware irqs */ |
| return irq < get_nr_hw_irqs(); |
| } |
| |
| static void pirq_unmask_notify(int irq) |
| { |
| struct physdev_eoi eoi = { .irq = irq }; |
| |
| if (unlikely(pirq_needs_eoi(irq))) { |
| int rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi); |
| WARN_ON(rc); |
| } |
| } |
| |
| static void pirq_query_unmask(int irq) |
| { |
| struct physdev_irq_status_query irq_status; |
| struct irq_info *info = info_for_irq(irq); |
| |
| BUG_ON(info->type != IRQT_PIRQ); |
| |
| irq_status.irq = irq; |
| if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status)) |
| irq_status.flags = 0; |
| |
| info->u.pirq.flags &= ~PIRQ_NEEDS_EOI; |
| if (irq_status.flags & XENIRQSTAT_needs_eoi) |
| info->u.pirq.flags |= PIRQ_NEEDS_EOI; |
| } |
| |
| static bool probing_irq(int irq) |
| { |
| struct irq_desc *desc = irq_to_desc(irq); |
| |
| return desc && desc->action == NULL; |
| } |
| |
| static unsigned int startup_pirq(unsigned int irq) |
| { |
| struct evtchn_bind_pirq bind_pirq; |
| struct irq_info *info = info_for_irq(irq); |
| int evtchn = evtchn_from_irq(irq); |
| int rc; |
| |
| BUG_ON(info->type != IRQT_PIRQ); |
| |
| if (VALID_EVTCHN(evtchn)) |
| goto out; |
| |
| bind_pirq.pirq = irq; |
| /* NB. We are happy to share unless we are probing. */ |
| bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ? |
| BIND_PIRQ__WILL_SHARE : 0; |
| rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq); |
| if (rc != 0) { |
| if (!probing_irq(irq)) |
| printk(KERN_INFO "Failed to obtain physical IRQ %d\n", |
| irq); |
| return 0; |
| } |
| evtchn = bind_pirq.port; |
| |
| pirq_query_unmask(irq); |
| |
| evtchn_to_irq[evtchn] = irq; |
| bind_evtchn_to_cpu(evtchn, 0); |
| info->evtchn = evtchn; |
| |
| out: |
| unmask_evtchn(evtchn); |
| pirq_unmask_notify(irq); |
| |
| return 0; |
| } |
| |
| static void shutdown_pirq(unsigned int irq) |
| { |
| struct evtchn_close close; |
| struct irq_info *info = info_for_irq(irq); |
| int evtchn = evtchn_from_irq(irq); |
| |
| BUG_ON(info->type != IRQT_PIRQ); |
| |
| if (!VALID_EVTCHN(evtchn)) |
| return; |
| |
| mask_evtchn(evtchn); |
| |
| close.port = evtchn; |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0) |
| BUG(); |
| |
| bind_evtchn_to_cpu(evtchn, 0); |
| evtchn_to_irq[evtchn] = -1; |
| info->evtchn = 0; |
| } |
| |
| static void enable_pirq(unsigned int irq) |
| { |
| startup_pirq(irq); |
| } |
| |
| static void disable_pirq(unsigned int irq) |
| { |
| } |
| |
| static void ack_pirq(unsigned int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| |
| move_native_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) { |
| mask_evtchn(evtchn); |
| clear_evtchn(evtchn); |
| } |
| } |
| |
| static void end_pirq(unsigned int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| struct irq_desc *desc = irq_to_desc(irq); |
| |
| if (WARN_ON(!desc)) |
| return; |
| |
| if ((desc->status & (IRQ_DISABLED|IRQ_PENDING)) == |
| (IRQ_DISABLED|IRQ_PENDING)) { |
| shutdown_pirq(irq); |
| } else if (VALID_EVTCHN(evtchn)) { |
| unmask_evtchn(evtchn); |
| pirq_unmask_notify(irq); |
| } |
| } |
| |
| static int find_irq_by_gsi(unsigned gsi) |
| { |
| int irq; |
| |
| for (irq = 0; irq < nr_irqs; irq++) { |
| struct irq_info *info = info_for_irq(irq); |
| |
| if (info == NULL || info->type != IRQT_PIRQ) |
| continue; |
| |
| if (gsi_from_irq(irq) == gsi) |
| return irq; |
| } |
| |
| return -1; |
| } |
| |
| /* xen_allocate_irq might allocate irqs from the top down, as a |
| * consequence don't assume that the irq number returned has a low value |
| * or can be used as a pirq number unless you know otherwise. |
| * |
| * One notable exception is when xen_allocate_irq is called passing an |
| * hardware gsi as argument, in that case the irq number returned |
| * matches the gsi number passed as first argument. |
| |
| * Note: We don't assign an |
| * event channel until the irq actually started up. Return an |
| * existing irq if we've already got one for the gsi. |
| */ |
| int xen_allocate_pirq(unsigned gsi, int shareable, char *name) |
| { |
| int irq; |
| struct physdev_irq irq_op; |
| |
| spin_lock(&irq_mapping_update_lock); |
| |
| irq = find_irq_by_gsi(gsi); |
| if (irq != -1) { |
| printk(KERN_INFO "xen_allocate_pirq: returning irq %d for gsi %u\n", |
| irq, gsi); |
| goto out; /* XXX need refcount? */ |
| } |
| |
| if (identity_mapped_irq(gsi)) { |
| irq = gsi; |
| irq_to_desc_alloc_node(irq, 0); |
| dynamic_irq_init(irq); |
| } else |
| irq = find_unbound_irq(); |
| |
| set_irq_chip_and_handler_name(irq, &xen_pirq_chip, |
| handle_level_irq, name); |
| |
| irq_op.irq = irq; |
| if (HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) { |
| dynamic_irq_cleanup(irq); |
| irq = -ENOSPC; |
| goto out; |
| } |
| |
| irq_info[irq] = mk_pirq_info(0, gsi, irq_op.vector); |
| irq_info[irq].u.pirq.flags |= shareable ? PIRQ_SHAREABLE : 0; |
| |
| out: |
| spin_unlock(&irq_mapping_update_lock); |
| |
| return irq; |
| } |
| |
| int xen_vector_from_irq(unsigned irq) |
| { |
| return vector_from_irq(irq); |
| } |
| |
| int xen_gsi_from_irq(unsigned irq) |
| { |
| return gsi_from_irq(irq); |
| } |
| |
| int bind_evtchn_to_irq(unsigned int evtchn) |
| { |
| int irq; |
| |
| spin_lock(&irq_mapping_update_lock); |
| |
| irq = evtchn_to_irq[evtchn]; |
| |
| if (irq == -1) { |
| irq = find_unbound_irq(); |
| |
| set_irq_chip_and_handler_name(irq, &xen_dynamic_chip, |
| handle_edge_irq, "event"); |
| |
| evtchn_to_irq[evtchn] = irq; |
| irq_info[irq] = mk_evtchn_info(evtchn); |
| } |
| |
| spin_unlock(&irq_mapping_update_lock); |
| |
| return irq; |
| } |
| EXPORT_SYMBOL_GPL(bind_evtchn_to_irq); |
| |
| static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) |
| { |
| struct evtchn_bind_ipi bind_ipi; |
| int evtchn, irq; |
| |
| spin_lock(&irq_mapping_update_lock); |
| |
| irq = per_cpu(ipi_to_irq, cpu)[ipi]; |
| |
| if (irq == -1) { |
| irq = find_unbound_irq(); |
| if (irq < 0) |
| goto out; |
| |
| set_irq_chip_and_handler_name(irq, &xen_percpu_chip, |
| handle_percpu_irq, "ipi"); |
| |
| bind_ipi.vcpu = cpu; |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi, |
| &bind_ipi) != 0) |
| BUG(); |
| evtchn = bind_ipi.port; |
| |
| evtchn_to_irq[evtchn] = irq; |
| irq_info[irq] = mk_ipi_info(evtchn, ipi); |
| per_cpu(ipi_to_irq, cpu)[ipi] = irq; |
| |
| bind_evtchn_to_cpu(evtchn, cpu); |
| } |
| |
| out: |
| spin_unlock(&irq_mapping_update_lock); |
| return irq; |
| } |
| |
| |
| static int bind_virq_to_irq(unsigned int virq, unsigned int cpu) |
| { |
| struct evtchn_bind_virq bind_virq; |
| int evtchn, irq; |
| |
| spin_lock(&irq_mapping_update_lock); |
| |
| irq = per_cpu(virq_to_irq, cpu)[virq]; |
| |
| if (irq == -1) { |
| bind_virq.virq = virq; |
| bind_virq.vcpu = cpu; |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, |
| &bind_virq) != 0) |
| BUG(); |
| evtchn = bind_virq.port; |
| |
| irq = find_unbound_irq(); |
| |
| set_irq_chip_and_handler_name(irq, &xen_percpu_chip, |
| handle_percpu_irq, "virq"); |
| |
| evtchn_to_irq[evtchn] = irq; |
| irq_info[irq] = mk_virq_info(evtchn, virq); |
| |
| per_cpu(virq_to_irq, cpu)[virq] = irq; |
| |
| bind_evtchn_to_cpu(evtchn, cpu); |
| } |
| |
| spin_unlock(&irq_mapping_update_lock); |
| |
| return irq; |
| } |
| |
| static void unbind_from_irq(unsigned int irq) |
| { |
| struct evtchn_close close; |
| int evtchn = evtchn_from_irq(irq); |
| |
| spin_lock(&irq_mapping_update_lock); |
| |
| if (VALID_EVTCHN(evtchn)) { |
| close.port = evtchn; |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0) |
| BUG(); |
| |
| switch (type_from_irq(irq)) { |
| case IRQT_VIRQ: |
| per_cpu(virq_to_irq, cpu_from_evtchn(evtchn)) |
| [virq_from_irq(irq)] = -1; |
| break; |
| case IRQT_IPI: |
| per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn)) |
| [ipi_from_irq(irq)] = -1; |
| break; |
| default: |
| break; |
| } |
| |
| /* Closed ports are implicitly re-bound to VCPU0. */ |
| bind_evtchn_to_cpu(evtchn, 0); |
| |
| evtchn_to_irq[evtchn] = -1; |
| } |
| |
| if (irq_info[irq].type != IRQT_UNBOUND) { |
| irq_info[irq] = mk_unbound_info(); |
| |
| irq_free_desc(irq); |
| } |
| |
| spin_unlock(&irq_mapping_update_lock); |
| } |
| |
| int bind_evtchn_to_irqhandler(unsigned int evtchn, |
| irq_handler_t handler, |
| unsigned long irqflags, |
| const char *devname, void *dev_id) |
| { |
| unsigned int irq; |
| int retval; |
| |
| irq = bind_evtchn_to_irq(evtchn); |
| retval = request_irq(irq, handler, irqflags, devname, dev_id); |
| if (retval != 0) { |
| unbind_from_irq(irq); |
| return retval; |
| } |
| |
| return irq; |
| } |
| EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler); |
| |
| int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu, |
| irq_handler_t handler, |
| unsigned long irqflags, const char *devname, void *dev_id) |
| { |
| unsigned int irq; |
| int retval; |
| |
| irq = bind_virq_to_irq(virq, cpu); |
| retval = request_irq(irq, handler, irqflags, devname, dev_id); |
| if (retval != 0) { |
| unbind_from_irq(irq); |
| return retval; |
| } |
| |
| return irq; |
| } |
| EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler); |
| |
| int bind_ipi_to_irqhandler(enum ipi_vector ipi, |
| unsigned int cpu, |
| irq_handler_t handler, |
| unsigned long irqflags, |
| const char *devname, |
| void *dev_id) |
| { |
| int irq, retval; |
| |
| irq = bind_ipi_to_irq(ipi, cpu); |
| if (irq < 0) |
| return irq; |
| |
| irqflags |= IRQF_NO_SUSPEND; |
| retval = request_irq(irq, handler, irqflags, devname, dev_id); |
| if (retval != 0) { |
| unbind_from_irq(irq); |
| return retval; |
| } |
| |
| return irq; |
| } |
| |
| void unbind_from_irqhandler(unsigned int irq, void *dev_id) |
| { |
| free_irq(irq, dev_id); |
| unbind_from_irq(irq); |
| } |
| EXPORT_SYMBOL_GPL(unbind_from_irqhandler); |
| |
| void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector) |
| { |
| int irq = per_cpu(ipi_to_irq, cpu)[vector]; |
| BUG_ON(irq < 0); |
| notify_remote_via_irq(irq); |
| } |
| |
| irqreturn_t xen_debug_interrupt(int irq, void *dev_id) |
| { |
| struct shared_info *sh = HYPERVISOR_shared_info; |
| int cpu = smp_processor_id(); |
| int i; |
| unsigned long flags; |
| static DEFINE_SPINLOCK(debug_lock); |
| |
| spin_lock_irqsave(&debug_lock, flags); |
| |
| printk("vcpu %d\n ", cpu); |
| |
| for_each_online_cpu(i) { |
| struct vcpu_info *v = per_cpu(xen_vcpu, i); |
| printk("%d: masked=%d pending=%d event_sel %08lx\n ", i, |
| (get_irq_regs() && i == cpu) ? xen_irqs_disabled(get_irq_regs()) : v->evtchn_upcall_mask, |
| v->evtchn_upcall_pending, |
| v->evtchn_pending_sel); |
| } |
| printk("pending:\n "); |
| for(i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--) |
| printk("%08lx%s", sh->evtchn_pending[i], |
| i % 8 == 0 ? "\n " : " "); |
| printk("\nmasks:\n "); |
| for(i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) |
| printk("%08lx%s", sh->evtchn_mask[i], |
| i % 8 == 0 ? "\n " : " "); |
| |
| printk("\nunmasked:\n "); |
| for(i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) |
| printk("%08lx%s", sh->evtchn_pending[i] & ~sh->evtchn_mask[i], |
| i % 8 == 0 ? "\n " : " "); |
| |
| printk("\npending list:\n"); |
| for(i = 0; i < NR_EVENT_CHANNELS; i++) { |
| if (sync_test_bit(i, sh->evtchn_pending)) { |
| printk(" %d: event %d -> irq %d\n", |
| cpu_from_evtchn(i), i, |
| evtchn_to_irq[i]); |
| } |
| } |
| |
| spin_unlock_irqrestore(&debug_lock, flags); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static DEFINE_PER_CPU(unsigned, xed_nesting_count); |
| |
| /* |
| * Search the CPUs pending events bitmasks. For each one found, map |
| * the event number to an irq, and feed it into do_IRQ() for |
| * handling. |
| * |
| * Xen uses a two-level bitmap to speed searching. The first level is |
| * a bitset of words which contain pending event bits. The second |
| * level is a bitset of pending events themselves. |
| */ |
| static void __xen_evtchn_do_upcall(void) |
| { |
| int cpu = get_cpu(); |
| struct shared_info *s = HYPERVISOR_shared_info; |
| struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu); |
| unsigned count; |
| |
| do { |
| unsigned long pending_words; |
| |
| vcpu_info->evtchn_upcall_pending = 0; |
| |
| if (__get_cpu_var(xed_nesting_count)++) |
| goto out; |
| |
| #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */ |
| /* Clear master flag /before/ clearing selector flag. */ |
| wmb(); |
| #endif |
| pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0); |
| while (pending_words != 0) { |
| unsigned long pending_bits; |
| int word_idx = __ffs(pending_words); |
| pending_words &= ~(1UL << word_idx); |
| |
| while ((pending_bits = active_evtchns(cpu, s, word_idx)) != 0) { |
| int bit_idx = __ffs(pending_bits); |
| int port = (word_idx * BITS_PER_LONG) + bit_idx; |
| int irq = evtchn_to_irq[port]; |
| struct irq_desc *desc; |
| |
| if (irq != -1) { |
| desc = irq_to_desc(irq); |
| if (desc) |
| generic_handle_irq_desc(irq, desc); |
| } |
| } |
| } |
| |
| BUG_ON(!irqs_disabled()); |
| |
| count = __get_cpu_var(xed_nesting_count); |
| __get_cpu_var(xed_nesting_count) = 0; |
| } while (count != 1 || vcpu_info->evtchn_upcall_pending); |
| |
| out: |
| |
| put_cpu(); |
| } |
| |
| void xen_evtchn_do_upcall(struct pt_regs *regs) |
| { |
| struct pt_regs *old_regs = set_irq_regs(regs); |
| |
| exit_idle(); |
| irq_enter(); |
| |
| __xen_evtchn_do_upcall(); |
| |
| irq_exit(); |
| set_irq_regs(old_regs); |
| } |
| |
| void xen_hvm_evtchn_do_upcall(void) |
| { |
| __xen_evtchn_do_upcall(); |
| } |
| EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall); |
| |
| /* Rebind a new event channel to an existing irq. */ |
| void rebind_evtchn_irq(int evtchn, int irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| /* Make sure the irq is masked, since the new event channel |
| will also be masked. */ |
| disable_irq(irq); |
| |
| spin_lock(&irq_mapping_update_lock); |
| |
| /* After resume the irq<->evtchn mappings are all cleared out */ |
| BUG_ON(evtchn_to_irq[evtchn] != -1); |
| /* Expect irq to have been bound before, |
| so there should be a proper type */ |
| BUG_ON(info->type == IRQT_UNBOUND); |
| |
| evtchn_to_irq[evtchn] = irq; |
| irq_info[irq] = mk_evtchn_info(evtchn); |
| |
| spin_unlock(&irq_mapping_update_lock); |
| |
| /* new event channels are always bound to cpu 0 */ |
| irq_set_affinity(irq, cpumask_of(0)); |
| |
| /* Unmask the event channel. */ |
| enable_irq(irq); |
| } |
| |
| /* Rebind an evtchn so that it gets delivered to a specific cpu */ |
| static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu) |
| { |
| struct evtchn_bind_vcpu bind_vcpu; |
| int evtchn = evtchn_from_irq(irq); |
| |
| /* events delivered via platform PCI interrupts are always |
| * routed to vcpu 0 */ |
| if (!VALID_EVTCHN(evtchn) || |
| (xen_hvm_domain() && !xen_have_vector_callback)) |
| return -1; |
| |
| /* Send future instances of this interrupt to other vcpu. */ |
| bind_vcpu.port = evtchn; |
| bind_vcpu.vcpu = tcpu; |
| |
| /* |
| * If this fails, it usually just indicates that we're dealing with a |
| * virq or IPI channel, which don't actually need to be rebound. Ignore |
| * it, but don't do the xenlinux-level rebind in that case. |
| */ |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0) |
| bind_evtchn_to_cpu(evtchn, tcpu); |
| |
| return 0; |
| } |
| |
| static int set_affinity_irq(unsigned irq, const struct cpumask *dest) |
| { |
| unsigned tcpu = cpumask_first(dest); |
| |
| return rebind_irq_to_cpu(irq, tcpu); |
| } |
| |
| int resend_irq_on_evtchn(unsigned int irq) |
| { |
| int masked, evtchn = evtchn_from_irq(irq); |
| struct shared_info *s = HYPERVISOR_shared_info; |
| |
| if (!VALID_EVTCHN(evtchn)) |
| return 1; |
| |
| masked = sync_test_and_set_bit(evtchn, s->evtchn_mask); |
| sync_set_bit(evtchn, s->evtchn_pending); |
| if (!masked) |
| unmask_evtchn(evtchn); |
| |
| return 1; |
| } |
| |
| static void enable_dynirq(unsigned int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| unmask_evtchn(evtchn); |
| } |
| |
| static void disable_dynirq(unsigned int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| mask_evtchn(evtchn); |
| } |
| |
| static void ack_dynirq(unsigned int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| |
| move_native_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| clear_evtchn(evtchn); |
| } |
| |
| static int retrigger_dynirq(unsigned int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| struct shared_info *sh = HYPERVISOR_shared_info; |
| int ret = 0; |
| |
| if (VALID_EVTCHN(evtchn)) { |
| int masked; |
| |
| masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask); |
| sync_set_bit(evtchn, sh->evtchn_pending); |
| if (!masked) |
| unmask_evtchn(evtchn); |
| ret = 1; |
| } |
| |
| return ret; |
| } |
| |
| static void restore_cpu_virqs(unsigned int cpu) |
| { |
| struct evtchn_bind_virq bind_virq; |
| int virq, irq, evtchn; |
| |
| for (virq = 0; virq < NR_VIRQS; virq++) { |
| if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1) |
| continue; |
| |
| BUG_ON(virq_from_irq(irq) != virq); |
| |
| /* Get a new binding from Xen. */ |
| bind_virq.virq = virq; |
| bind_virq.vcpu = cpu; |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, |
| &bind_virq) != 0) |
| BUG(); |
| evtchn = bind_virq.port; |
| |
| /* Record the new mapping. */ |
| evtchn_to_irq[evtchn] = irq; |
| irq_info[irq] = mk_virq_info(evtchn, virq); |
| bind_evtchn_to_cpu(evtchn, cpu); |
| |
| /* Ready for use. */ |
| unmask_evtchn(evtchn); |
| } |
| } |
| |
| static void restore_cpu_ipis(unsigned int cpu) |
| { |
| struct evtchn_bind_ipi bind_ipi; |
| int ipi, irq, evtchn; |
| |
| for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) { |
| if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1) |
| continue; |
| |
| BUG_ON(ipi_from_irq(irq) != ipi); |
| |
| /* Get a new binding from Xen. */ |
| bind_ipi.vcpu = cpu; |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi, |
| &bind_ipi) != 0) |
| BUG(); |
| evtchn = bind_ipi.port; |
| |
| /* Record the new mapping. */ |
| evtchn_to_irq[evtchn] = irq; |
| irq_info[irq] = mk_ipi_info(evtchn, ipi); |
| bind_evtchn_to_cpu(evtchn, cpu); |
| |
| /* Ready for use. */ |
| unmask_evtchn(evtchn); |
| |
| } |
| } |
| |
| /* Clear an irq's pending state, in preparation for polling on it */ |
| void xen_clear_irq_pending(int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| clear_evtchn(evtchn); |
| } |
| EXPORT_SYMBOL(xen_clear_irq_pending); |
| void xen_set_irq_pending(int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| set_evtchn(evtchn); |
| } |
| |
| bool xen_test_irq_pending(int irq) |
| { |
| int evtchn = evtchn_from_irq(irq); |
| bool ret = false; |
| |
| if (VALID_EVTCHN(evtchn)) |
| ret = test_evtchn(evtchn); |
| |
| return ret; |
| } |
| |
| /* Poll waiting for an irq to become pending with timeout. In the usual case, |
| * the irq will be disabled so it won't deliver an interrupt. */ |
| void xen_poll_irq_timeout(int irq, u64 timeout) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) { |
| struct sched_poll poll; |
| |
| poll.nr_ports = 1; |
| poll.timeout = timeout; |
| set_xen_guest_handle(poll.ports, &evtchn); |
| |
| if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0) |
| BUG(); |
| } |
| } |
| EXPORT_SYMBOL(xen_poll_irq_timeout); |
| /* Poll waiting for an irq to become pending. In the usual case, the |
| * irq will be disabled so it won't deliver an interrupt. */ |
| void xen_poll_irq(int irq) |
| { |
| xen_poll_irq_timeout(irq, 0 /* no timeout */); |
| } |
| |
| void xen_irq_resume(void) |
| { |
| unsigned int cpu, irq, evtchn; |
| |
| init_evtchn_cpu_bindings(); |
| |
| /* New event-channel space is not 'live' yet. */ |
| for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++) |
| mask_evtchn(evtchn); |
| |
| /* No IRQ <-> event-channel mappings. */ |
| for (irq = 0; irq < nr_irqs; irq++) |
| irq_info[irq].evtchn = 0; /* zap event-channel binding */ |
| |
| for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++) |
| evtchn_to_irq[evtchn] = -1; |
| |
| for_each_possible_cpu(cpu) { |
| restore_cpu_virqs(cpu); |
| restore_cpu_ipis(cpu); |
| } |
| } |
| |
| static struct irq_chip xen_dynamic_chip __read_mostly = { |
| .name = "xen-dyn", |
| |
| .disable = disable_dynirq, |
| .mask = disable_dynirq, |
| .unmask = enable_dynirq, |
| |
| .ack = ack_dynirq, |
| .set_affinity = set_affinity_irq, |
| .retrigger = retrigger_dynirq, |
| }; |
| |
| static struct irq_chip xen_pirq_chip __read_mostly = { |
| .name = "xen-pirq", |
| |
| .startup = startup_pirq, |
| .shutdown = shutdown_pirq, |
| |
| .enable = enable_pirq, |
| .unmask = enable_pirq, |
| |
| .disable = disable_pirq, |
| .mask = disable_pirq, |
| |
| .ack = ack_pirq, |
| .end = end_pirq, |
| |
| .set_affinity = set_affinity_irq, |
| |
| .retrigger = retrigger_dynirq, |
| }; |
| |
| static struct irq_chip xen_percpu_chip __read_mostly = { |
| .name = "xen-percpu", |
| |
| .disable = disable_dynirq, |
| .mask = disable_dynirq, |
| .unmask = enable_dynirq, |
| |
| .ack = ack_dynirq, |
| }; |
| |
| int xen_set_callback_via(uint64_t via) |
| { |
| struct xen_hvm_param a; |
| a.domid = DOMID_SELF; |
| a.index = HVM_PARAM_CALLBACK_IRQ; |
| a.value = via; |
| return HYPERVISOR_hvm_op(HVMOP_set_param, &a); |
| } |
| EXPORT_SYMBOL_GPL(xen_set_callback_via); |
| |
| #ifdef CONFIG_XEN_PVHVM |
| /* Vector callbacks are better than PCI interrupts to receive event |
| * channel notifications because we can receive vector callbacks on any |
| * vcpu and we don't need PCI support or APIC interactions. */ |
| void xen_callback_vector(void) |
| { |
| int rc; |
| uint64_t callback_via; |
| if (xen_have_vector_callback) { |
| callback_via = HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK); |
| rc = xen_set_callback_via(callback_via); |
| if (rc) { |
| printk(KERN_ERR "Request for Xen HVM callback vector" |
| " failed.\n"); |
| xen_have_vector_callback = 0; |
| return; |
| } |
| printk(KERN_INFO "Xen HVM callback vector for event delivery is " |
| "enabled\n"); |
| /* in the restore case the vector has already been allocated */ |
| if (!test_bit(XEN_HVM_EVTCHN_CALLBACK, used_vectors)) |
| alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK, xen_hvm_callback_vector); |
| } |
| } |
| #else |
| void xen_callback_vector(void) {} |
| #endif |
| |
| void __init xen_init_IRQ(void) |
| { |
| int i; |
| |
| cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s), |
| GFP_KERNEL); |
| irq_info = kcalloc(nr_irqs, sizeof(*irq_info), GFP_KERNEL); |
| |
| evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq), |
| GFP_KERNEL); |
| for (i = 0; i < NR_EVENT_CHANNELS; i++) |
| evtchn_to_irq[i] = -1; |
| |
| init_evtchn_cpu_bindings(); |
| |
| /* No event channels are 'live' right now. */ |
| for (i = 0; i < NR_EVENT_CHANNELS; i++) |
| mask_evtchn(i); |
| |
| if (xen_hvm_domain()) { |
| xen_callback_vector(); |
| native_init_IRQ(); |
| } else { |
| irq_ctx_init(smp_processor_id()); |
| } |
| } |