4 * Xen models interrupts with abstract event channels. Because each
5 * domain gets 1024 event channels, but NR_IRQ is not that large, we
6 * must dynamically map irqs<->event channels. The event channels
7 * interface with the rest of the kernel by defining a xen interrupt
8 * chip. When an event is received, it is mapped to an irq and sent
9 * through the normal interrupt processing path.
11 * There are four kinds of events which can be mapped to an event
14 * 1. Inter-domain notifications. This includes all the virtual
15 * device events, since they're driven by front-ends in another domain
17 * 2. VIRQs, typically used for timers. These are per-cpu events.
19 * 4. PIRQs - Hardware interrupts.
21 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
24 #include <linux/linkage.h>
25 #include <linux/interrupt.h>
26 #include <linux/irq.h>
27 #include <linux/module.h>
28 #include <linux/string.h>
29 #include <linux/bootmem.h>
30 #include <linux/slab.h>
31 #include <linux/irqnr.h>
32 #include <linux/pci.h>
36 #include <asm/ptrace.h>
39 #include <asm/io_apic.h>
40 #include <asm/xen/page.h>
41 #include <asm/xen/pci.h>
43 #include <asm/sync_bitops.h>
44 #include <asm/xen/hypercall.h>
45 #include <asm/xen/hypervisor.h>
49 #include <xen/xen-ops.h>
50 #include <xen/events.h>
51 #include <xen/interface/xen.h>
52 #include <xen/interface/event_channel.h>
53 #include <xen/interface/hvm/hvm_op.h>
54 #include <xen/interface/hvm/params.h>
55 #include <xen/interface/physdev.h>
56 #include <xen/interface/sched.h>
57 #include <asm/hw_irq.h>
60 * This lock protects updates to the following mapping and reference-count
61 * arrays. The lock does not need to be acquired to read the mapping tables.
63 static DEFINE_MUTEX(irq_mapping_update_lock);
65 static LIST_HEAD(xen_irq_list_head);
67 /* IRQ <-> VIRQ mapping. */
68 static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1};
70 /* IRQ <-> IPI mapping */
71 static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1};
73 /* Interrupt types. */
83 * Packed IRQ information:
84 * type - enum xen_irq_type
85 * event channel - irq->event channel mapping
86 * cpu - cpu this event channel is bound to
87 * index - type-specific information:
88 * PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM
89 * guest, or GSI (real passthrough IRQ) of the device.
95 struct list_head list;
97 enum xen_irq_type type; /* type */
99 unsigned short evtchn; /* event channel */
100 unsigned short cpu; /* cpu bound */
108 unsigned char vector;
114 #define PIRQ_NEEDS_EOI (1 << 0)
115 #define PIRQ_SHAREABLE (1 << 1)
117 static int *evtchn_to_irq;
118 static unsigned long *pirq_eoi_map;
119 static bool (*pirq_needs_eoi)(unsigned irq);
121 static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
124 /* Xen will never allocate port zero for any purpose. */
125 #define VALID_EVTCHN(chn) ((chn) != 0)
127 static struct irq_chip xen_dynamic_chip;
128 static struct irq_chip xen_percpu_chip;
129 static struct irq_chip xen_pirq_chip;
130 static void enable_dynirq(struct irq_data *data);
131 static void disable_dynirq(struct irq_data *data);
133 /* Get info for IRQ */
134 static struct irq_info *info_for_irq(unsigned irq)
136 return irq_get_handler_data(irq);
139 /* Constructors for packed IRQ information. */
140 static void xen_irq_info_common_init(struct irq_info *info,
142 enum xen_irq_type type,
143 unsigned short evtchn,
147 BUG_ON(info->type != IRQT_UNBOUND && info->type != type);
151 info->evtchn = evtchn;
154 evtchn_to_irq[evtchn] = irq;
157 static void xen_irq_info_evtchn_init(unsigned irq,
158 unsigned short evtchn)
160 struct irq_info *info = info_for_irq(irq);
162 xen_irq_info_common_init(info, irq, IRQT_EVTCHN, evtchn, 0);
165 static void xen_irq_info_ipi_init(unsigned cpu,
167 unsigned short evtchn,
170 struct irq_info *info = info_for_irq(irq);
172 xen_irq_info_common_init(info, irq, IRQT_IPI, evtchn, 0);
176 per_cpu(ipi_to_irq, cpu)[ipi] = irq;
179 static void xen_irq_info_virq_init(unsigned cpu,
181 unsigned short evtchn,
184 struct irq_info *info = info_for_irq(irq);
186 xen_irq_info_common_init(info, irq, IRQT_VIRQ, evtchn, 0);
190 per_cpu(virq_to_irq, cpu)[virq] = irq;
193 static void xen_irq_info_pirq_init(unsigned irq,
194 unsigned short evtchn,
197 unsigned short vector,
201 struct irq_info *info = info_for_irq(irq);
203 xen_irq_info_common_init(info, irq, IRQT_PIRQ, evtchn, 0);
205 info->u.pirq.pirq = pirq;
206 info->u.pirq.gsi = gsi;
207 info->u.pirq.vector = vector;
208 info->u.pirq.domid = domid;
209 info->u.pirq.flags = flags;
213 * Accessors for packed IRQ information.
215 static unsigned int evtchn_from_irq(unsigned irq)
217 if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq)))
220 return info_for_irq(irq)->evtchn;
223 unsigned irq_from_evtchn(unsigned int evtchn)
225 return evtchn_to_irq[evtchn];
227 EXPORT_SYMBOL_GPL(irq_from_evtchn);
229 static enum ipi_vector ipi_from_irq(unsigned irq)
231 struct irq_info *info = info_for_irq(irq);
233 BUG_ON(info == NULL);
234 BUG_ON(info->type != IRQT_IPI);
239 static unsigned virq_from_irq(unsigned irq)
241 struct irq_info *info = info_for_irq(irq);
243 BUG_ON(info == NULL);
244 BUG_ON(info->type != IRQT_VIRQ);
249 static unsigned pirq_from_irq(unsigned irq)
251 struct irq_info *info = info_for_irq(irq);
253 BUG_ON(info == NULL);
254 BUG_ON(info->type != IRQT_PIRQ);
256 return info->u.pirq.pirq;
259 static enum xen_irq_type type_from_irq(unsigned irq)
261 return info_for_irq(irq)->type;
264 static unsigned cpu_from_irq(unsigned irq)
266 return info_for_irq(irq)->cpu;
269 static unsigned int cpu_from_evtchn(unsigned int evtchn)
271 int irq = evtchn_to_irq[evtchn];
275 ret = cpu_from_irq(irq);
280 static bool pirq_check_eoi_map(unsigned irq)
282 return test_bit(pirq_from_irq(irq), pirq_eoi_map);
285 static bool pirq_needs_eoi_flag(unsigned irq)
287 struct irq_info *info = info_for_irq(irq);
288 BUG_ON(info->type != IRQT_PIRQ);
290 return info->u.pirq.flags & PIRQ_NEEDS_EOI;
293 static inline unsigned long active_evtchns(unsigned int cpu,
294 struct shared_info *sh,
297 return sh->evtchn_pending[idx] &
298 per_cpu(cpu_evtchn_mask, cpu)[idx] &
299 ~sh->evtchn_mask[idx];
302 static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
304 int irq = evtchn_to_irq[chn];
308 cpumask_copy(irq_to_desc(irq)->irq_data.affinity, cpumask_of(cpu));
311 clear_bit(chn, per_cpu(cpu_evtchn_mask, cpu_from_irq(irq)));
312 set_bit(chn, per_cpu(cpu_evtchn_mask, cpu));
314 info_for_irq(irq)->cpu = cpu;
317 static void init_evtchn_cpu_bindings(void)
321 struct irq_info *info;
323 /* By default all event channels notify CPU#0. */
324 list_for_each_entry(info, &xen_irq_list_head, list) {
325 struct irq_desc *desc = irq_to_desc(info->irq);
326 cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
330 for_each_possible_cpu(i)
331 memset(per_cpu(cpu_evtchn_mask, i),
332 (i == 0) ? ~0 : 0, sizeof(*per_cpu(cpu_evtchn_mask, i)));
335 static inline void clear_evtchn(int port)
337 struct shared_info *s = HYPERVISOR_shared_info;
338 sync_clear_bit(port, &s->evtchn_pending[0]);
341 static inline void set_evtchn(int port)
343 struct shared_info *s = HYPERVISOR_shared_info;
344 sync_set_bit(port, &s->evtchn_pending[0]);
347 static inline int test_evtchn(int port)
349 struct shared_info *s = HYPERVISOR_shared_info;
350 return sync_test_bit(port, &s->evtchn_pending[0]);
355 * notify_remote_via_irq - send event to remote end of event channel via irq
356 * @irq: irq of event channel to send event to
358 * Unlike notify_remote_via_evtchn(), this is safe to use across
359 * save/restore. Notifications on a broken connection are silently
362 void notify_remote_via_irq(int irq)
364 int evtchn = evtchn_from_irq(irq);
366 if (VALID_EVTCHN(evtchn))
367 notify_remote_via_evtchn(evtchn);
369 EXPORT_SYMBOL_GPL(notify_remote_via_irq);
371 static void mask_evtchn(int port)
373 struct shared_info *s = HYPERVISOR_shared_info;
374 sync_set_bit(port, &s->evtchn_mask[0]);
377 static void unmask_evtchn(int port)
379 struct shared_info *s = HYPERVISOR_shared_info;
380 unsigned int cpu = get_cpu();
381 int do_hypercall = 0, evtchn_pending = 0;
383 BUG_ON(!irqs_disabled());
385 if (unlikely((cpu != cpu_from_evtchn(port))))
388 evtchn_pending = sync_test_bit(port, &s->evtchn_pending[0]);
390 if (unlikely(evtchn_pending && xen_hvm_domain()))
393 /* Slow path (hypercall) if this is a non-local port or if this is
394 * an hvm domain and an event is pending (hvm domains don't have
395 * their own implementation of irq_enable). */
397 struct evtchn_unmask unmask = { .port = port };
398 (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask);
400 struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
402 sync_clear_bit(port, &s->evtchn_mask[0]);
405 * The following is basically the equivalent of
406 * 'hw_resend_irq'. Just like a real IO-APIC we 'lose
407 * the interrupt edge' if the channel is masked.
409 if (evtchn_pending &&
410 !sync_test_and_set_bit(port / BITS_PER_LONG,
411 &vcpu_info->evtchn_pending_sel))
412 vcpu_info->evtchn_upcall_pending = 1;
418 static void xen_irq_init(unsigned irq)
420 struct irq_info *info;
422 struct irq_desc *desc = irq_to_desc(irq);
424 /* By default all event channels notify CPU#0. */
425 cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
428 info = kzalloc(sizeof(*info), GFP_KERNEL);
430 panic("Unable to allocate metadata for IRQ%d\n", irq);
432 info->type = IRQT_UNBOUND;
435 irq_set_handler_data(irq, info);
437 list_add_tail(&info->list, &xen_irq_list_head);
440 static int __must_check xen_allocate_irq_dynamic(void)
445 #ifdef CONFIG_X86_IO_APIC
447 * For an HVM guest or domain 0 which see "real" (emulated or
448 * actual respectively) GSIs we allocate dynamic IRQs
449 * e.g. those corresponding to event channels or MSIs
450 * etc. from the range above those "real" GSIs to avoid
453 if (xen_initial_domain() || xen_hvm_domain())
454 first = get_nr_irqs_gsi();
457 irq = irq_alloc_desc_from(first, -1);
465 static int __must_check xen_allocate_irq_gsi(unsigned gsi)
470 * A PV guest has no concept of a GSI (since it has no ACPI
471 * nor access to/knowledge of the physical APICs). Therefore
472 * all IRQs are dynamically allocated from the entire IRQ
475 if (xen_pv_domain() && !xen_initial_domain())
476 return xen_allocate_irq_dynamic();
478 /* Legacy IRQ descriptors are already allocated by the arch. */
479 if (gsi < NR_IRQS_LEGACY)
482 irq = irq_alloc_desc_at(gsi, -1);
489 static void xen_free_irq(unsigned irq)
491 struct irq_info *info = irq_get_handler_data(irq);
493 list_del(&info->list);
495 irq_set_handler_data(irq, NULL);
497 WARN_ON(info->refcnt > 0);
501 /* Legacy IRQ descriptors are managed by the arch. */
502 if (irq < NR_IRQS_LEGACY)
508 static void pirq_query_unmask(int irq)
510 struct physdev_irq_status_query irq_status;
511 struct irq_info *info = info_for_irq(irq);
513 BUG_ON(info->type != IRQT_PIRQ);
515 irq_status.irq = pirq_from_irq(irq);
516 if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
517 irq_status.flags = 0;
519 info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
520 if (irq_status.flags & XENIRQSTAT_needs_eoi)
521 info->u.pirq.flags |= PIRQ_NEEDS_EOI;
524 static bool probing_irq(int irq)
526 struct irq_desc *desc = irq_to_desc(irq);
528 return desc && desc->action == NULL;
531 static void eoi_pirq(struct irq_data *data)
533 int evtchn = evtchn_from_irq(data->irq);
534 struct physdev_eoi eoi = { .irq = pirq_from_irq(data->irq) };
539 if (VALID_EVTCHN(evtchn))
540 clear_evtchn(evtchn);
542 if (pirq_needs_eoi(data->irq)) {
543 rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
548 static void mask_ack_pirq(struct irq_data *data)
550 disable_dynirq(data);
554 static unsigned int __startup_pirq(unsigned int irq)
556 struct evtchn_bind_pirq bind_pirq;
557 struct irq_info *info = info_for_irq(irq);
558 int evtchn = evtchn_from_irq(irq);
561 BUG_ON(info->type != IRQT_PIRQ);
563 if (VALID_EVTCHN(evtchn))
566 bind_pirq.pirq = pirq_from_irq(irq);
567 /* NB. We are happy to share unless we are probing. */
568 bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
569 BIND_PIRQ__WILL_SHARE : 0;
570 rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
572 if (!probing_irq(irq))
573 printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
577 evtchn = bind_pirq.port;
579 pirq_query_unmask(irq);
581 evtchn_to_irq[evtchn] = irq;
582 bind_evtchn_to_cpu(evtchn, 0);
583 info->evtchn = evtchn;
586 unmask_evtchn(evtchn);
587 eoi_pirq(irq_get_irq_data(irq));
592 static unsigned int startup_pirq(struct irq_data *data)
594 return __startup_pirq(data->irq);
597 static void shutdown_pirq(struct irq_data *data)
599 struct evtchn_close close;
600 unsigned int irq = data->irq;
601 struct irq_info *info = info_for_irq(irq);
602 int evtchn = evtchn_from_irq(irq);
604 BUG_ON(info->type != IRQT_PIRQ);
606 if (!VALID_EVTCHN(evtchn))
612 if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
615 bind_evtchn_to_cpu(evtchn, 0);
616 evtchn_to_irq[evtchn] = -1;
620 static void enable_pirq(struct irq_data *data)
625 static void disable_pirq(struct irq_data *data)
627 disable_dynirq(data);
630 int xen_irq_from_gsi(unsigned gsi)
632 struct irq_info *info;
634 list_for_each_entry(info, &xen_irq_list_head, list) {
635 if (info->type != IRQT_PIRQ)
638 if (info->u.pirq.gsi == gsi)
644 EXPORT_SYMBOL_GPL(xen_irq_from_gsi);
647 * Do not make any assumptions regarding the relationship between the
648 * IRQ number returned here and the Xen pirq argument.
650 * Note: We don't assign an event channel until the irq actually started
651 * up. Return an existing irq if we've already got one for the gsi.
653 * Shareable implies level triggered, not shareable implies edge
656 int xen_bind_pirq_gsi_to_irq(unsigned gsi,
657 unsigned pirq, int shareable, char *name)
660 struct physdev_irq irq_op;
662 mutex_lock(&irq_mapping_update_lock);
664 irq = xen_irq_from_gsi(gsi);
666 printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n",
671 irq = xen_allocate_irq_gsi(gsi);
678 /* Only the privileged domain can do this. For non-priv, the pcifront
679 * driver provides a PCI bus that does the call to do exactly
680 * this in the priv domain. */
681 if (xen_initial_domain() &&
682 HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
688 xen_irq_info_pirq_init(irq, 0, pirq, gsi, irq_op.vector, DOMID_SELF,
689 shareable ? PIRQ_SHAREABLE : 0);
691 pirq_query_unmask(irq);
692 /* We try to use the handler with the appropriate semantic for the
693 * type of interrupt: if the interrupt is an edge triggered
694 * interrupt we use handle_edge_irq.
696 * On the other hand if the interrupt is level triggered we use
697 * handle_fasteoi_irq like the native code does for this kind of
700 * Depending on the Xen version, pirq_needs_eoi might return true
701 * not only for level triggered interrupts but for edge triggered
702 * interrupts too. In any case Xen always honors the eoi mechanism,
703 * not injecting any more pirqs of the same kind if the first one
704 * hasn't received an eoi yet. Therefore using the fasteoi handler
705 * is the right choice either way.
708 irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
709 handle_fasteoi_irq, name);
711 irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
712 handle_edge_irq, name);
715 mutex_unlock(&irq_mapping_update_lock);
720 #ifdef CONFIG_PCI_MSI
721 int xen_allocate_pirq_msi(struct pci_dev *dev, struct msi_desc *msidesc)
724 struct physdev_get_free_pirq op_get_free_pirq;
726 op_get_free_pirq.type = MAP_PIRQ_TYPE_MSI;
727 rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);
729 WARN_ONCE(rc == -ENOSYS,
730 "hypervisor does not support the PHYSDEVOP_get_free_pirq interface\n");
732 return rc ? -1 : op_get_free_pirq.pirq;
735 int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
736 int pirq, int vector, const char *name,
741 mutex_lock(&irq_mapping_update_lock);
743 irq = xen_allocate_irq_dynamic();
747 irq_set_chip_and_handler_name(irq, &xen_pirq_chip, handle_edge_irq,
750 xen_irq_info_pirq_init(irq, 0, pirq, 0, vector, domid, 0);
751 ret = irq_set_msi_desc(irq, msidesc);
755 mutex_unlock(&irq_mapping_update_lock);
758 mutex_unlock(&irq_mapping_update_lock);
764 int xen_destroy_irq(int irq)
766 struct irq_desc *desc;
767 struct physdev_unmap_pirq unmap_irq;
768 struct irq_info *info = info_for_irq(irq);
771 mutex_lock(&irq_mapping_update_lock);
773 desc = irq_to_desc(irq);
777 if (xen_initial_domain()) {
778 unmap_irq.pirq = info->u.pirq.pirq;
779 unmap_irq.domid = info->u.pirq.domid;
780 rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
781 /* If another domain quits without making the pci_disable_msix
782 * call, the Xen hypervisor takes care of freeing the PIRQs
783 * (free_domain_pirqs).
785 if ((rc == -ESRCH && info->u.pirq.domid != DOMID_SELF))
786 printk(KERN_INFO "domain %d does not have %d anymore\n",
787 info->u.pirq.domid, info->u.pirq.pirq);
789 printk(KERN_WARNING "unmap irq failed %d\n", rc);
797 mutex_unlock(&irq_mapping_update_lock);
801 int xen_irq_from_pirq(unsigned pirq)
805 struct irq_info *info;
807 mutex_lock(&irq_mapping_update_lock);
809 list_for_each_entry(info, &xen_irq_list_head, list) {
810 if (info->type != IRQT_PIRQ)
813 if (info->u.pirq.pirq == pirq)
818 mutex_unlock(&irq_mapping_update_lock);
824 int xen_pirq_from_irq(unsigned irq)
826 return pirq_from_irq(irq);
828 EXPORT_SYMBOL_GPL(xen_pirq_from_irq);
829 int bind_evtchn_to_irq(unsigned int evtchn)
833 mutex_lock(&irq_mapping_update_lock);
835 irq = evtchn_to_irq[evtchn];
838 irq = xen_allocate_irq_dynamic();
842 irq_set_chip_and_handler_name(irq, &xen_dynamic_chip,
843 handle_edge_irq, "event");
845 xen_irq_info_evtchn_init(irq, evtchn);
847 struct irq_info *info = info_for_irq(irq);
848 WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
850 irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);
853 mutex_unlock(&irq_mapping_update_lock);
857 EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
859 static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
861 struct evtchn_bind_ipi bind_ipi;
864 mutex_lock(&irq_mapping_update_lock);
866 irq = per_cpu(ipi_to_irq, cpu)[ipi];
869 irq = xen_allocate_irq_dynamic();
873 irq_set_chip_and_handler_name(irq, &xen_percpu_chip,
874 handle_percpu_irq, "ipi");
877 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
880 evtchn = bind_ipi.port;
882 xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
884 bind_evtchn_to_cpu(evtchn, cpu);
886 struct irq_info *info = info_for_irq(irq);
887 WARN_ON(info == NULL || info->type != IRQT_IPI);
891 mutex_unlock(&irq_mapping_update_lock);
895 static int bind_interdomain_evtchn_to_irq(unsigned int remote_domain,
896 unsigned int remote_port)
898 struct evtchn_bind_interdomain bind_interdomain;
901 bind_interdomain.remote_dom = remote_domain;
902 bind_interdomain.remote_port = remote_port;
904 err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain,
907 return err ? : bind_evtchn_to_irq(bind_interdomain.local_port);
910 static int find_virq(unsigned int virq, unsigned int cpu)
912 struct evtchn_status status;
913 int port, rc = -ENOENT;
915 memset(&status, 0, sizeof(status));
916 for (port = 0; port <= NR_EVENT_CHANNELS; port++) {
917 status.dom = DOMID_SELF;
919 rc = HYPERVISOR_event_channel_op(EVTCHNOP_status, &status);
922 if (status.status != EVTCHNSTAT_virq)
924 if (status.u.virq == virq && status.vcpu == cpu) {
932 int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
934 struct evtchn_bind_virq bind_virq;
935 int evtchn, irq, ret;
937 mutex_lock(&irq_mapping_update_lock);
939 irq = per_cpu(virq_to_irq, cpu)[virq];
942 irq = xen_allocate_irq_dynamic();
946 irq_set_chip_and_handler_name(irq, &xen_percpu_chip,
947 handle_percpu_irq, "virq");
949 bind_virq.virq = virq;
950 bind_virq.vcpu = cpu;
951 ret = HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
954 evtchn = bind_virq.port;
957 ret = find_virq(virq, cpu);
962 xen_irq_info_virq_init(cpu, irq, evtchn, virq);
964 bind_evtchn_to_cpu(evtchn, cpu);
966 struct irq_info *info = info_for_irq(irq);
967 WARN_ON(info == NULL || info->type != IRQT_VIRQ);
971 mutex_unlock(&irq_mapping_update_lock);
976 static void unbind_from_irq(unsigned int irq)
978 struct evtchn_close close;
979 int evtchn = evtchn_from_irq(irq);
980 struct irq_info *info = irq_get_handler_data(irq);
982 mutex_lock(&irq_mapping_update_lock);
984 if (info->refcnt > 0) {
986 if (info->refcnt != 0)
990 if (VALID_EVTCHN(evtchn)) {
992 if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
995 switch (type_from_irq(irq)) {
997 per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
998 [virq_from_irq(irq)] = -1;
1001 per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
1002 [ipi_from_irq(irq)] = -1;
1008 /* Closed ports are implicitly re-bound to VCPU0. */
1009 bind_evtchn_to_cpu(evtchn, 0);
1011 evtchn_to_irq[evtchn] = -1;
1014 BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);
1019 mutex_unlock(&irq_mapping_update_lock);
1022 int bind_evtchn_to_irqhandler(unsigned int evtchn,
1023 irq_handler_t handler,
1024 unsigned long irqflags,
1025 const char *devname, void *dev_id)
1029 irq = bind_evtchn_to_irq(evtchn);
1032 retval = request_irq(irq, handler, irqflags, devname, dev_id);
1034 unbind_from_irq(irq);
1040 EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler);
1042 int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain,
1043 unsigned int remote_port,
1044 irq_handler_t handler,
1045 unsigned long irqflags,
1046 const char *devname,
1051 irq = bind_interdomain_evtchn_to_irq(remote_domain, remote_port);
1055 retval = request_irq(irq, handler, irqflags, devname, dev_id);
1057 unbind_from_irq(irq);
1063 EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irqhandler);
1065 int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
1066 irq_handler_t handler,
1067 unsigned long irqflags, const char *devname, void *dev_id)
1071 irq = bind_virq_to_irq(virq, cpu);
1074 retval = request_irq(irq, handler, irqflags, devname, dev_id);
1076 unbind_from_irq(irq);
1082 EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);
1084 int bind_ipi_to_irqhandler(enum ipi_vector ipi,
1086 irq_handler_t handler,
1087 unsigned long irqflags,
1088 const char *devname,
1093 irq = bind_ipi_to_irq(ipi, cpu);
1097 irqflags |= IRQF_NO_SUSPEND | IRQF_FORCE_RESUME | IRQF_EARLY_RESUME;
1098 retval = request_irq(irq, handler, irqflags, devname, dev_id);
1100 unbind_from_irq(irq);
1107 void unbind_from_irqhandler(unsigned int irq, void *dev_id)
1109 free_irq(irq, dev_id);
1110 unbind_from_irq(irq);
1112 EXPORT_SYMBOL_GPL(unbind_from_irqhandler);
1114 int evtchn_make_refcounted(unsigned int evtchn)
1116 int irq = evtchn_to_irq[evtchn];
1117 struct irq_info *info;
1122 info = irq_get_handler_data(irq);
1127 WARN_ON(info->refcnt != -1);
1133 EXPORT_SYMBOL_GPL(evtchn_make_refcounted);
1135 int evtchn_get(unsigned int evtchn)
1138 struct irq_info *info;
1141 if (evtchn >= NR_EVENT_CHANNELS)
1144 mutex_lock(&irq_mapping_update_lock);
1146 irq = evtchn_to_irq[evtchn];
1150 info = irq_get_handler_data(irq);
1156 if (info->refcnt <= 0)
1162 mutex_unlock(&irq_mapping_update_lock);
1166 EXPORT_SYMBOL_GPL(evtchn_get);
1168 void evtchn_put(unsigned int evtchn)
1170 int irq = evtchn_to_irq[evtchn];
1171 if (WARN_ON(irq == -1))
1173 unbind_from_irq(irq);
1175 EXPORT_SYMBOL_GPL(evtchn_put);
1177 void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
1179 int irq = per_cpu(ipi_to_irq, cpu)[vector];
1181 notify_remote_via_irq(irq);
1184 irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
1186 struct shared_info *sh = HYPERVISOR_shared_info;
1187 int cpu = smp_processor_id();
1188 unsigned long *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu);
1190 unsigned long flags;
1191 static DEFINE_SPINLOCK(debug_lock);
1192 struct vcpu_info *v;
1194 spin_lock_irqsave(&debug_lock, flags);
1196 printk("\nvcpu %d\n ", cpu);
1198 for_each_online_cpu(i) {
1200 v = per_cpu(xen_vcpu, i);
1201 pending = (get_irq_regs() && i == cpu)
1202 ? xen_irqs_disabled(get_irq_regs())
1203 : v->evtchn_upcall_mask;
1204 printk("%d: masked=%d pending=%d event_sel %0*lx\n ", i,
1205 pending, v->evtchn_upcall_pending,
1206 (int)(sizeof(v->evtchn_pending_sel)*2),
1207 v->evtchn_pending_sel);
1209 v = per_cpu(xen_vcpu, cpu);
1211 printk("\npending:\n ");
1212 for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--)
1213 printk("%0*lx%s", (int)sizeof(sh->evtchn_pending[0])*2,
1214 sh->evtchn_pending[i],
1215 i % 8 == 0 ? "\n " : " ");
1216 printk("\nglobal mask:\n ");
1217 for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
1219 (int)(sizeof(sh->evtchn_mask[0])*2),
1221 i % 8 == 0 ? "\n " : " ");
1223 printk("\nglobally unmasked:\n ");
1224 for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
1225 printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
1226 sh->evtchn_pending[i] & ~sh->evtchn_mask[i],
1227 i % 8 == 0 ? "\n " : " ");
1229 printk("\nlocal cpu%d mask:\n ", cpu);
1230 for (i = (NR_EVENT_CHANNELS/BITS_PER_LONG)-1; i >= 0; i--)
1231 printk("%0*lx%s", (int)(sizeof(cpu_evtchn[0])*2),
1233 i % 8 == 0 ? "\n " : " ");
1235 printk("\nlocally unmasked:\n ");
1236 for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) {
1237 unsigned long pending = sh->evtchn_pending[i]
1238 & ~sh->evtchn_mask[i]
1240 printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
1241 pending, i % 8 == 0 ? "\n " : " ");
1244 printk("\npending list:\n");
1245 for (i = 0; i < NR_EVENT_CHANNELS; i++) {
1246 if (sync_test_bit(i, sh->evtchn_pending)) {
1247 int word_idx = i / BITS_PER_LONG;
1248 printk(" %d: event %d -> irq %d%s%s%s\n",
1249 cpu_from_evtchn(i), i,
1251 sync_test_bit(word_idx, &v->evtchn_pending_sel)
1253 !sync_test_bit(i, sh->evtchn_mask)
1254 ? "" : " globally-masked",
1255 sync_test_bit(i, cpu_evtchn)
1256 ? "" : " locally-masked");
1260 spin_unlock_irqrestore(&debug_lock, flags);
1265 static DEFINE_PER_CPU(unsigned, xed_nesting_count);
1266 static DEFINE_PER_CPU(unsigned int, current_word_idx);
1267 static DEFINE_PER_CPU(unsigned int, current_bit_idx);
1270 * Mask out the i least significant bits of w
1272 #define MASK_LSBS(w, i) (w & ((~0UL) << i))
1275 * Search the CPUs pending events bitmasks. For each one found, map
1276 * the event number to an irq, and feed it into do_IRQ() for
1279 * Xen uses a two-level bitmap to speed searching. The first level is
1280 * a bitset of words which contain pending event bits. The second
1281 * level is a bitset of pending events themselves.
1283 static void __xen_evtchn_do_upcall(void)
1285 int start_word_idx, start_bit_idx;
1286 int word_idx, bit_idx;
1288 int cpu = get_cpu();
1289 struct shared_info *s = HYPERVISOR_shared_info;
1290 struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
1294 unsigned long pending_words;
1296 vcpu_info->evtchn_upcall_pending = 0;
1298 if (__this_cpu_inc_return(xed_nesting_count) - 1)
1301 #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
1302 /* Clear master flag /before/ clearing selector flag. */
1305 pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
1307 start_word_idx = __this_cpu_read(current_word_idx);
1308 start_bit_idx = __this_cpu_read(current_bit_idx);
1310 word_idx = start_word_idx;
1312 for (i = 0; pending_words != 0; i++) {
1313 unsigned long pending_bits;
1314 unsigned long words;
1316 words = MASK_LSBS(pending_words, word_idx);
1319 * If we masked out all events, wrap to beginning.
1326 word_idx = __ffs(words);
1328 pending_bits = active_evtchns(cpu, s, word_idx);
1329 bit_idx = 0; /* usually scan entire word from start */
1330 if (word_idx == start_word_idx) {
1331 /* We scan the starting word in two parts */
1333 /* 1st time: start in the middle */
1334 bit_idx = start_bit_idx;
1336 /* 2nd time: mask bits done already */
1337 bit_idx &= (1UL << start_bit_idx) - 1;
1343 struct irq_desc *desc;
1345 bits = MASK_LSBS(pending_bits, bit_idx);
1347 /* If we masked out all events, move on. */
1351 bit_idx = __ffs(bits);
1354 port = (word_idx * BITS_PER_LONG) + bit_idx;
1355 irq = evtchn_to_irq[port];
1358 desc = irq_to_desc(irq);
1360 generic_handle_irq_desc(irq, desc);
1363 bit_idx = (bit_idx + 1) % BITS_PER_LONG;
1365 /* Next caller starts at last processed + 1 */
1366 __this_cpu_write(current_word_idx,
1367 bit_idx ? word_idx :
1368 (word_idx+1) % BITS_PER_LONG);
1369 __this_cpu_write(current_bit_idx, bit_idx);
1370 } while (bit_idx != 0);
1372 /* Scan start_l1i twice; all others once. */
1373 if ((word_idx != start_word_idx) || (i != 0))
1374 pending_words &= ~(1UL << word_idx);
1376 word_idx = (word_idx + 1) % BITS_PER_LONG;
1379 BUG_ON(!irqs_disabled());
1381 count = __this_cpu_read(xed_nesting_count);
1382 __this_cpu_write(xed_nesting_count, 0);
1383 } while (count != 1 || vcpu_info->evtchn_upcall_pending);
1390 void xen_evtchn_do_upcall(struct pt_regs *regs)
1392 struct pt_regs *old_regs = set_irq_regs(regs);
1399 __xen_evtchn_do_upcall();
1402 set_irq_regs(old_regs);
1405 void xen_hvm_evtchn_do_upcall(void)
1407 __xen_evtchn_do_upcall();
1409 EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall);
1411 /* Rebind a new event channel to an existing irq. */
1412 void rebind_evtchn_irq(int evtchn, int irq)
1414 struct irq_info *info = info_for_irq(irq);
1416 /* Make sure the irq is masked, since the new event channel
1417 will also be masked. */
1420 mutex_lock(&irq_mapping_update_lock);
1422 /* After resume the irq<->evtchn mappings are all cleared out */
1423 BUG_ON(evtchn_to_irq[evtchn] != -1);
1424 /* Expect irq to have been bound before,
1425 so there should be a proper type */
1426 BUG_ON(info->type == IRQT_UNBOUND);
1428 xen_irq_info_evtchn_init(irq, evtchn);
1430 mutex_unlock(&irq_mapping_update_lock);
1432 /* new event channels are always bound to cpu 0 */
1433 irq_set_affinity(irq, cpumask_of(0));
1435 /* Unmask the event channel. */
1439 /* Rebind an evtchn so that it gets delivered to a specific cpu */
1440 static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
1442 struct evtchn_bind_vcpu bind_vcpu;
1443 int evtchn = evtchn_from_irq(irq);
1445 if (!VALID_EVTCHN(evtchn))
1449 * Events delivered via platform PCI interrupts are always
1450 * routed to vcpu 0 and hence cannot be rebound.
1452 if (xen_hvm_domain() && !xen_have_vector_callback)
1455 /* Send future instances of this interrupt to other vcpu. */
1456 bind_vcpu.port = evtchn;
1457 bind_vcpu.vcpu = tcpu;
1460 * If this fails, it usually just indicates that we're dealing with a
1461 * virq or IPI channel, which don't actually need to be rebound. Ignore
1462 * it, but don't do the xenlinux-level rebind in that case.
1464 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
1465 bind_evtchn_to_cpu(evtchn, tcpu);
1470 static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest,
1473 unsigned tcpu = cpumask_first(dest);
1475 return rebind_irq_to_cpu(data->irq, tcpu);
1478 int resend_irq_on_evtchn(unsigned int irq)
1480 int masked, evtchn = evtchn_from_irq(irq);
1481 struct shared_info *s = HYPERVISOR_shared_info;
1483 if (!VALID_EVTCHN(evtchn))
1486 masked = sync_test_and_set_bit(evtchn, s->evtchn_mask);
1487 sync_set_bit(evtchn, s->evtchn_pending);
1489 unmask_evtchn(evtchn);
1494 static void enable_dynirq(struct irq_data *data)
1496 int evtchn = evtchn_from_irq(data->irq);
1498 if (VALID_EVTCHN(evtchn))
1499 unmask_evtchn(evtchn);
1502 static void disable_dynirq(struct irq_data *data)
1504 int evtchn = evtchn_from_irq(data->irq);
1506 if (VALID_EVTCHN(evtchn))
1507 mask_evtchn(evtchn);
1510 static void ack_dynirq(struct irq_data *data)
1512 int evtchn = evtchn_from_irq(data->irq);
1516 if (VALID_EVTCHN(evtchn))
1517 clear_evtchn(evtchn);
1520 static void mask_ack_dynirq(struct irq_data *data)
1522 disable_dynirq(data);
1526 static int retrigger_dynirq(struct irq_data *data)
1528 int evtchn = evtchn_from_irq(data->irq);
1529 struct shared_info *sh = HYPERVISOR_shared_info;
1532 if (VALID_EVTCHN(evtchn)) {
1535 masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask);
1536 sync_set_bit(evtchn, sh->evtchn_pending);
1538 unmask_evtchn(evtchn);
1545 static void restore_pirqs(void)
1547 int pirq, rc, irq, gsi;
1548 struct physdev_map_pirq map_irq;
1549 struct irq_info *info;
1551 list_for_each_entry(info, &xen_irq_list_head, list) {
1552 if (info->type != IRQT_PIRQ)
1555 pirq = info->u.pirq.pirq;
1556 gsi = info->u.pirq.gsi;
1559 /* save/restore of PT devices doesn't work, so at this point the
1560 * only devices present are GSI based emulated devices */
1564 map_irq.domid = DOMID_SELF;
1565 map_irq.type = MAP_PIRQ_TYPE_GSI;
1566 map_irq.index = gsi;
1567 map_irq.pirq = pirq;
1569 rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
1571 printk(KERN_WARNING "xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
1572 gsi, irq, pirq, rc);
1577 printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
1579 __startup_pirq(irq);
1583 static void restore_cpu_virqs(unsigned int cpu)
1585 struct evtchn_bind_virq bind_virq;
1586 int virq, irq, evtchn;
1588 for (virq = 0; virq < NR_VIRQS; virq++) {
1589 if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1)
1592 BUG_ON(virq_from_irq(irq) != virq);
1594 /* Get a new binding from Xen. */
1595 bind_virq.virq = virq;
1596 bind_virq.vcpu = cpu;
1597 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
1600 evtchn = bind_virq.port;
1602 /* Record the new mapping. */
1603 xen_irq_info_virq_init(cpu, irq, evtchn, virq);
1604 bind_evtchn_to_cpu(evtchn, cpu);
1608 static void restore_cpu_ipis(unsigned int cpu)
1610 struct evtchn_bind_ipi bind_ipi;
1611 int ipi, irq, evtchn;
1613 for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) {
1614 if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1)
1617 BUG_ON(ipi_from_irq(irq) != ipi);
1619 /* Get a new binding from Xen. */
1620 bind_ipi.vcpu = cpu;
1621 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
1624 evtchn = bind_ipi.port;
1626 /* Record the new mapping. */
1627 xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
1628 bind_evtchn_to_cpu(evtchn, cpu);
1632 /* Clear an irq's pending state, in preparation for polling on it */
1633 void xen_clear_irq_pending(int irq)
1635 int evtchn = evtchn_from_irq(irq);
1637 if (VALID_EVTCHN(evtchn))
1638 clear_evtchn(evtchn);
1640 EXPORT_SYMBOL(xen_clear_irq_pending);
1641 void xen_set_irq_pending(int irq)
1643 int evtchn = evtchn_from_irq(irq);
1645 if (VALID_EVTCHN(evtchn))
1649 bool xen_test_irq_pending(int irq)
1651 int evtchn = evtchn_from_irq(irq);
1654 if (VALID_EVTCHN(evtchn))
1655 ret = test_evtchn(evtchn);
1660 /* Poll waiting for an irq to become pending with timeout. In the usual case,
1661 * the irq will be disabled so it won't deliver an interrupt. */
1662 void xen_poll_irq_timeout(int irq, u64 timeout)
1664 evtchn_port_t evtchn = evtchn_from_irq(irq);
1666 if (VALID_EVTCHN(evtchn)) {
1667 struct sched_poll poll;
1670 poll.timeout = timeout;
1671 set_xen_guest_handle(poll.ports, &evtchn);
1673 if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
1677 EXPORT_SYMBOL(xen_poll_irq_timeout);
1678 /* Poll waiting for an irq to become pending. In the usual case, the
1679 * irq will be disabled so it won't deliver an interrupt. */
1680 void xen_poll_irq(int irq)
1682 xen_poll_irq_timeout(irq, 0 /* no timeout */);
1685 /* Check whether the IRQ line is shared with other guests. */
1686 int xen_test_irq_shared(int irq)
1688 struct irq_info *info = info_for_irq(irq);
1689 struct physdev_irq_status_query irq_status = { .irq = info->u.pirq.pirq };
1691 if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
1693 return !(irq_status.flags & XENIRQSTAT_shared);
1695 EXPORT_SYMBOL_GPL(xen_test_irq_shared);
1697 void xen_irq_resume(void)
1699 unsigned int cpu, evtchn;
1700 struct irq_info *info;
1702 init_evtchn_cpu_bindings();
1704 /* New event-channel space is not 'live' yet. */
1705 for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
1706 mask_evtchn(evtchn);
1708 /* No IRQ <-> event-channel mappings. */
1709 list_for_each_entry(info, &xen_irq_list_head, list)
1710 info->evtchn = 0; /* zap event-channel binding */
1712 for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
1713 evtchn_to_irq[evtchn] = -1;
1715 for_each_possible_cpu(cpu) {
1716 restore_cpu_virqs(cpu);
1717 restore_cpu_ipis(cpu);
1723 static struct irq_chip xen_dynamic_chip __read_mostly = {
1726 .irq_disable = disable_dynirq,
1727 .irq_mask = disable_dynirq,
1728 .irq_unmask = enable_dynirq,
1730 .irq_ack = ack_dynirq,
1731 .irq_mask_ack = mask_ack_dynirq,
1733 .irq_set_affinity = set_affinity_irq,
1734 .irq_retrigger = retrigger_dynirq,
1737 static struct irq_chip xen_pirq_chip __read_mostly = {
1740 .irq_startup = startup_pirq,
1741 .irq_shutdown = shutdown_pirq,
1742 .irq_enable = enable_pirq,
1743 .irq_disable = disable_pirq,
1745 .irq_mask = disable_dynirq,
1746 .irq_unmask = enable_dynirq,
1748 .irq_ack = eoi_pirq,
1749 .irq_eoi = eoi_pirq,
1750 .irq_mask_ack = mask_ack_pirq,
1752 .irq_set_affinity = set_affinity_irq,
1754 .irq_retrigger = retrigger_dynirq,
1757 static struct irq_chip xen_percpu_chip __read_mostly = {
1758 .name = "xen-percpu",
1760 .irq_disable = disable_dynirq,
1761 .irq_mask = disable_dynirq,
1762 .irq_unmask = enable_dynirq,
1764 .irq_ack = ack_dynirq,
1767 int xen_set_callback_via(uint64_t via)
1769 struct xen_hvm_param a;
1770 a.domid = DOMID_SELF;
1771 a.index = HVM_PARAM_CALLBACK_IRQ;
1773 return HYPERVISOR_hvm_op(HVMOP_set_param, &a);
1775 EXPORT_SYMBOL_GPL(xen_set_callback_via);
1777 #ifdef CONFIG_XEN_PVHVM
1778 /* Vector callbacks are better than PCI interrupts to receive event
1779 * channel notifications because we can receive vector callbacks on any
1780 * vcpu and we don't need PCI support or APIC interactions. */
1781 void xen_callback_vector(void)
1784 uint64_t callback_via;
1785 if (xen_have_vector_callback) {
1786 callback_via = HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK);
1787 rc = xen_set_callback_via(callback_via);
1789 printk(KERN_ERR "Request for Xen HVM callback vector"
1791 xen_have_vector_callback = 0;
1794 printk(KERN_INFO "Xen HVM callback vector for event delivery is "
1796 /* in the restore case the vector has already been allocated */
1797 if (!test_bit(XEN_HVM_EVTCHN_CALLBACK, used_vectors))
1798 alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK, xen_hvm_callback_vector);
1802 void xen_callback_vector(void) {}
1805 void __init xen_init_IRQ(void)
1809 evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
1811 BUG_ON(!evtchn_to_irq);
1812 for (i = 0; i < NR_EVENT_CHANNELS; i++)
1813 evtchn_to_irq[i] = -1;
1815 init_evtchn_cpu_bindings();
1817 /* No event channels are 'live' right now. */
1818 for (i = 0; i < NR_EVENT_CHANNELS; i++)
1821 pirq_needs_eoi = pirq_needs_eoi_flag;
1824 if (xen_hvm_domain()) {
1825 xen_callback_vector();
1827 /* pci_xen_hvm_init must be called after native_init_IRQ so that
1828 * __acpi_register_gsi can point at the right function */
1832 struct physdev_pirq_eoi_gmfn eoi_gmfn;
1834 irq_ctx_init(smp_processor_id());
1835 if (xen_initial_domain())
1836 pci_xen_initial_domain();
1838 pirq_eoi_map = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
1839 eoi_gmfn.gmfn = virt_to_mfn(pirq_eoi_map);
1840 rc = HYPERVISOR_physdev_op(PHYSDEVOP_pirq_eoi_gmfn_v2, &eoi_gmfn);
1842 free_page((unsigned long) pirq_eoi_map);
1843 pirq_eoi_map = NULL;
1845 pirq_needs_eoi = pirq_check_eoi_map;