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 recieved, 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>
35 #include <asm/ptrace.h>
38 #include <asm/io_apic.h>
39 #include <asm/sync_bitops.h>
40 #include <asm/xen/pci.h>
41 #include <asm/xen/hypercall.h>
42 #include <asm/xen/hypervisor.h>
46 #include <xen/xen-ops.h>
47 #include <xen/events.h>
48 #include <xen/interface/xen.h>
49 #include <xen/interface/event_channel.h>
50 #include <xen/interface/hvm/hvm_op.h>
51 #include <xen/interface/hvm/params.h>
54 * This lock protects updates to the following mapping and reference-count
55 * arrays. The lock does not need to be acquired to read the mapping tables.
57 static DEFINE_SPINLOCK(irq_mapping_update_lock);
59 /* IRQ <-> VIRQ mapping. */
60 static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1};
62 /* IRQ <-> IPI mapping */
63 static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1};
65 /* Interrupt types. */
75 * Packed IRQ information:
76 * type - enum xen_irq_type
77 * event channel - irq->event channel mapping
78 * cpu - cpu this event channel is bound to
79 * index - type-specific information:
80 * PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM
81 * guest, or GSI (real passthrough IRQ) of the device.
88 enum xen_irq_type type; /* type */
89 unsigned short evtchn; /* event channel */
90 unsigned short cpu; /* cpu bound */
103 #define PIRQ_NEEDS_EOI (1 << 0)
104 #define PIRQ_SHAREABLE (1 << 1)
106 static struct irq_info *irq_info;
107 static int *pirq_to_irq;
109 static int *evtchn_to_irq;
110 struct cpu_evtchn_s {
111 unsigned long bits[NR_EVENT_CHANNELS/BITS_PER_LONG];
114 static __initdata struct cpu_evtchn_s init_evtchn_mask = {
115 .bits[0 ... (NR_EVENT_CHANNELS/BITS_PER_LONG)-1] = ~0ul,
117 static struct cpu_evtchn_s *cpu_evtchn_mask_p = &init_evtchn_mask;
119 static inline unsigned long *cpu_evtchn_mask(int cpu)
121 return cpu_evtchn_mask_p[cpu].bits;
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;
131 /* Constructor for packed IRQ information. */
132 static struct irq_info mk_unbound_info(void)
134 return (struct irq_info) { .type = IRQT_UNBOUND };
137 static struct irq_info mk_evtchn_info(unsigned short evtchn)
139 return (struct irq_info) { .type = IRQT_EVTCHN, .evtchn = evtchn,
143 static struct irq_info mk_ipi_info(unsigned short evtchn, enum ipi_vector ipi)
145 return (struct irq_info) { .type = IRQT_IPI, .evtchn = evtchn,
146 .cpu = 0, .u.ipi = ipi };
149 static struct irq_info mk_virq_info(unsigned short evtchn, unsigned short virq)
151 return (struct irq_info) { .type = IRQT_VIRQ, .evtchn = evtchn,
152 .cpu = 0, .u.virq = virq };
155 static struct irq_info mk_pirq_info(unsigned short evtchn, unsigned short pirq,
156 unsigned short gsi, unsigned short vector)
158 return (struct irq_info) { .type = IRQT_PIRQ, .evtchn = evtchn,
160 .u.pirq = { .pirq = pirq, .gsi = gsi, .vector = vector } };
164 * Accessors for packed IRQ information.
166 static struct irq_info *info_for_irq(unsigned irq)
168 return &irq_info[irq];
171 static unsigned int evtchn_from_irq(unsigned irq)
173 if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq)))
176 return info_for_irq(irq)->evtchn;
179 unsigned irq_from_evtchn(unsigned int evtchn)
181 return evtchn_to_irq[evtchn];
183 EXPORT_SYMBOL_GPL(irq_from_evtchn);
185 static enum ipi_vector ipi_from_irq(unsigned irq)
187 struct irq_info *info = info_for_irq(irq);
189 BUG_ON(info == NULL);
190 BUG_ON(info->type != IRQT_IPI);
195 static unsigned virq_from_irq(unsigned irq)
197 struct irq_info *info = info_for_irq(irq);
199 BUG_ON(info == NULL);
200 BUG_ON(info->type != IRQT_VIRQ);
205 static unsigned pirq_from_irq(unsigned irq)
207 struct irq_info *info = info_for_irq(irq);
209 BUG_ON(info == NULL);
210 BUG_ON(info->type != IRQT_PIRQ);
212 return info->u.pirq.pirq;
215 static unsigned gsi_from_irq(unsigned irq)
217 struct irq_info *info = info_for_irq(irq);
219 BUG_ON(info == NULL);
220 BUG_ON(info->type != IRQT_PIRQ);
222 return info->u.pirq.gsi;
225 static unsigned vector_from_irq(unsigned irq)
227 struct irq_info *info = info_for_irq(irq);
229 BUG_ON(info == NULL);
230 BUG_ON(info->type != IRQT_PIRQ);
232 return info->u.pirq.vector;
235 static enum xen_irq_type type_from_irq(unsigned irq)
237 return info_for_irq(irq)->type;
240 static unsigned cpu_from_irq(unsigned irq)
242 return info_for_irq(irq)->cpu;
245 static unsigned int cpu_from_evtchn(unsigned int evtchn)
247 int irq = evtchn_to_irq[evtchn];
251 ret = cpu_from_irq(irq);
256 static bool pirq_needs_eoi(unsigned irq)
258 struct irq_info *info = info_for_irq(irq);
260 BUG_ON(info->type != IRQT_PIRQ);
262 return info->u.pirq.flags & PIRQ_NEEDS_EOI;
265 static inline unsigned long active_evtchns(unsigned int cpu,
266 struct shared_info *sh,
269 return (sh->evtchn_pending[idx] &
270 cpu_evtchn_mask(cpu)[idx] &
271 ~sh->evtchn_mask[idx]);
274 static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
276 int irq = evtchn_to_irq[chn];
280 cpumask_copy(irq_to_desc(irq)->irq_data.affinity, cpumask_of(cpu));
283 clear_bit(chn, cpu_evtchn_mask(cpu_from_irq(irq)));
284 set_bit(chn, cpu_evtchn_mask(cpu));
286 irq_info[irq].cpu = cpu;
289 static void init_evtchn_cpu_bindings(void)
293 struct irq_desc *desc;
295 /* By default all event channels notify CPU#0. */
296 for_each_irq_desc(i, desc) {
297 cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
301 for_each_possible_cpu(i)
302 memset(cpu_evtchn_mask(i),
303 (i == 0) ? ~0 : 0, sizeof(struct cpu_evtchn_s));
307 static inline void clear_evtchn(int port)
309 struct shared_info *s = HYPERVISOR_shared_info;
310 sync_clear_bit(port, &s->evtchn_pending[0]);
313 static inline void set_evtchn(int port)
315 struct shared_info *s = HYPERVISOR_shared_info;
316 sync_set_bit(port, &s->evtchn_pending[0]);
319 static inline int test_evtchn(int port)
321 struct shared_info *s = HYPERVISOR_shared_info;
322 return sync_test_bit(port, &s->evtchn_pending[0]);
327 * notify_remote_via_irq - send event to remote end of event channel via irq
328 * @irq: irq of event channel to send event to
330 * Unlike notify_remote_via_evtchn(), this is safe to use across
331 * save/restore. Notifications on a broken connection are silently
334 void notify_remote_via_irq(int irq)
336 int evtchn = evtchn_from_irq(irq);
338 if (VALID_EVTCHN(evtchn))
339 notify_remote_via_evtchn(evtchn);
341 EXPORT_SYMBOL_GPL(notify_remote_via_irq);
343 static void mask_evtchn(int port)
345 struct shared_info *s = HYPERVISOR_shared_info;
346 sync_set_bit(port, &s->evtchn_mask[0]);
349 static void unmask_evtchn(int port)
351 struct shared_info *s = HYPERVISOR_shared_info;
352 unsigned int cpu = get_cpu();
354 BUG_ON(!irqs_disabled());
356 /* Slow path (hypercall) if this is a non-local port. */
357 if (unlikely(cpu != cpu_from_evtchn(port))) {
358 struct evtchn_unmask unmask = { .port = port };
359 (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask);
361 struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
363 sync_clear_bit(port, &s->evtchn_mask[0]);
366 * The following is basically the equivalent of
367 * 'hw_resend_irq'. Just like a real IO-APIC we 'lose
368 * the interrupt edge' if the channel is masked.
370 if (sync_test_bit(port, &s->evtchn_pending[0]) &&
371 !sync_test_and_set_bit(port / BITS_PER_LONG,
372 &vcpu_info->evtchn_pending_sel))
373 vcpu_info->evtchn_upcall_pending = 1;
379 static int xen_allocate_irq_dynamic(void)
384 #ifdef CONFIG_X86_IO_APIC
386 * For an HVM guest or domain 0 which see "real" (emulated or
387 * actual repectively) GSIs we allocate dynamic IRQs
388 * e.g. those corresponding to event channels or MSIs
389 * etc. from the range above those "real" GSIs to avoid
392 if (xen_initial_domain() || xen_hvm_domain())
393 first = get_nr_irqs_gsi();
397 irq = irq_alloc_desc_from(first, -1);
399 if (irq == -ENOMEM && first > NR_IRQS_LEGACY) {
400 printk(KERN_ERR "Out of dynamic IRQ space and eating into GSI space. You should increase nr_irqs\n");
401 first = max(NR_IRQS_LEGACY, first - NR_IRQS_LEGACY);
406 panic("No available IRQ to bind to: increase nr_irqs!\n");
411 static int xen_allocate_irq_gsi(unsigned gsi)
416 * A PV guest has no concept of a GSI (since it has no ACPI
417 * nor access to/knowledge of the physical APICs). Therefore
418 * all IRQs are dynamically allocated from the entire IRQ
421 if (xen_pv_domain() && !xen_initial_domain())
422 return xen_allocate_irq_dynamic();
424 /* Legacy IRQ descriptors are already allocated by the arch. */
425 if (gsi < NR_IRQS_LEGACY)
428 irq = irq_alloc_desc_at(gsi, -1);
430 panic("Unable to allocate to IRQ%d (%d)\n", gsi, irq);
435 static void xen_free_irq(unsigned irq)
437 /* Legacy IRQ descriptors are managed by the arch. */
438 if (irq < NR_IRQS_LEGACY)
444 static void pirq_unmask_notify(int irq)
446 struct physdev_eoi eoi = { .irq = pirq_from_irq(irq) };
448 if (unlikely(pirq_needs_eoi(irq))) {
449 int rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
454 static void pirq_query_unmask(int irq)
456 struct physdev_irq_status_query irq_status;
457 struct irq_info *info = info_for_irq(irq);
459 BUG_ON(info->type != IRQT_PIRQ);
461 irq_status.irq = pirq_from_irq(irq);
462 if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
463 irq_status.flags = 0;
465 info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
466 if (irq_status.flags & XENIRQSTAT_needs_eoi)
467 info->u.pirq.flags |= PIRQ_NEEDS_EOI;
470 static bool probing_irq(int irq)
472 struct irq_desc *desc = irq_to_desc(irq);
474 return desc && desc->action == NULL;
477 static unsigned int __startup_pirq(unsigned int irq)
479 struct evtchn_bind_pirq bind_pirq;
480 struct irq_info *info = info_for_irq(irq);
481 int evtchn = evtchn_from_irq(irq);
484 BUG_ON(info->type != IRQT_PIRQ);
486 if (VALID_EVTCHN(evtchn))
489 bind_pirq.pirq = pirq_from_irq(irq);
490 /* NB. We are happy to share unless we are probing. */
491 bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
492 BIND_PIRQ__WILL_SHARE : 0;
493 rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
495 if (!probing_irq(irq))
496 printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
500 evtchn = bind_pirq.port;
502 pirq_query_unmask(irq);
504 evtchn_to_irq[evtchn] = irq;
505 bind_evtchn_to_cpu(evtchn, 0);
506 info->evtchn = evtchn;
509 unmask_evtchn(evtchn);
510 pirq_unmask_notify(irq);
515 static unsigned int startup_pirq(struct irq_data *data)
517 return __startup_pirq(data->irq);
520 static void shutdown_pirq(struct irq_data *data)
522 struct evtchn_close close;
523 unsigned int irq = data->irq;
524 struct irq_info *info = info_for_irq(irq);
525 int evtchn = evtchn_from_irq(irq);
527 BUG_ON(info->type != IRQT_PIRQ);
529 if (!VALID_EVTCHN(evtchn))
535 if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
538 bind_evtchn_to_cpu(evtchn, 0);
539 evtchn_to_irq[evtchn] = -1;
543 static void enable_pirq(struct irq_data *data)
548 static void disable_pirq(struct irq_data *data)
552 static void ack_pirq(struct irq_data *data)
554 int evtchn = evtchn_from_irq(data->irq);
556 move_native_irq(data->irq);
558 if (VALID_EVTCHN(evtchn)) {
560 clear_evtchn(evtchn);
564 static int find_irq_by_gsi(unsigned gsi)
568 for (irq = 0; irq < nr_irqs; irq++) {
569 struct irq_info *info = info_for_irq(irq);
571 if (info == NULL || info->type != IRQT_PIRQ)
574 if (gsi_from_irq(irq) == gsi)
581 int xen_allocate_pirq(unsigned gsi, int shareable, char *name)
583 return xen_map_pirq_gsi(gsi, gsi, shareable, name);
586 /* xen_map_pirq_gsi might allocate irqs from the top down, as a
587 * consequence don't assume that the irq number returned has a low value
588 * or can be used as a pirq number unless you know otherwise.
590 * One notable exception is when xen_map_pirq_gsi is called passing an
591 * hardware gsi as argument, in that case the irq number returned
592 * matches the gsi number passed as second argument.
594 * Note: We don't assign an event channel until the irq actually started
595 * up. Return an existing irq if we've already got one for the gsi.
597 int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)
600 struct physdev_irq irq_op;
602 spin_lock(&irq_mapping_update_lock);
604 if ((pirq > nr_irqs) || (gsi > nr_irqs)) {
605 printk(KERN_WARNING "xen_map_pirq_gsi: %s %s is incorrect!\n",
606 pirq > nr_irqs ? "pirq" :"",
607 gsi > nr_irqs ? "gsi" : "");
611 irq = find_irq_by_gsi(gsi);
613 printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n",
615 goto out; /* XXX need refcount? */
618 irq = xen_allocate_irq_gsi(gsi);
620 set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
621 handle_level_irq, name);
626 /* Only the privileged domain can do this. For non-priv, the pcifront
627 * driver provides a PCI bus that does the call to do exactly
628 * this in the priv domain. */
629 if (xen_initial_domain() &&
630 HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
636 irq_info[irq] = mk_pirq_info(0, pirq, gsi, irq_op.vector);
637 irq_info[irq].u.pirq.flags |= shareable ? PIRQ_SHAREABLE : 0;
638 pirq_to_irq[pirq] = irq;
641 spin_unlock(&irq_mapping_update_lock);
646 #ifdef CONFIG_PCI_MSI
647 #include <linux/msi.h>
648 #include "../pci/msi.h"
650 int xen_allocate_pirq_msi(struct pci_dev *dev, struct msi_desc *msidesc)
653 struct physdev_get_free_pirq op_get_free_pirq;
655 op_get_free_pirq.type = MAP_PIRQ_TYPE_MSI;
656 rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);
658 WARN_ONCE(rc == -ENOSYS,
659 "hypervisor does not support the PHYSDEVOP_get_free_pirq interface\n");
661 return rc ? -1 : op_get_free_pirq.pirq;
664 int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
665 int pirq, int vector, const char *name)
669 spin_lock(&irq_mapping_update_lock);
671 irq = xen_allocate_irq_dynamic();
675 set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
676 handle_level_irq, name);
678 irq_info[irq] = mk_pirq_info(0, pirq, 0, vector);
679 pirq_to_irq[pirq] = irq;
680 ret = set_irq_msi(irq, msidesc);
684 spin_unlock(&irq_mapping_update_lock);
687 spin_unlock(&irq_mapping_update_lock);
692 int xen_create_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int type)
694 struct physdev_map_pirq map_irq;
697 u32 table_offset, bir;
699 memset(&map_irq, 0, sizeof(map_irq));
700 map_irq.domid = DOMID_SELF;
701 map_irq.type = MAP_PIRQ_TYPE_MSI;
704 map_irq.bus = dev->bus->number;
705 map_irq.devfn = dev->devfn;
707 if (type == PCI_CAP_ID_MSIX) {
708 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
710 pci_read_config_dword(dev, msix_table_offset_reg(pos),
712 bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
714 map_irq.table_base = pci_resource_start(dev, bir);
715 map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
718 rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
720 dev_warn(&dev->dev, "xen map irq failed %d\n", rc);
724 return xen_bind_pirq_msi_to_irq(dev, msidesc,
725 map_irq.pirq, map_irq.index,
726 (type == PCI_CAP_ID_MSIX) ?
731 int xen_destroy_irq(int irq)
733 struct irq_desc *desc;
734 struct physdev_unmap_pirq unmap_irq;
735 struct irq_info *info = info_for_irq(irq);
738 spin_lock(&irq_mapping_update_lock);
740 desc = irq_to_desc(irq);
744 if (xen_initial_domain()) {
745 unmap_irq.pirq = info->u.pirq.pirq;
746 unmap_irq.domid = DOMID_SELF;
747 rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
749 printk(KERN_WARNING "unmap irq failed %d\n", rc);
753 pirq_to_irq[info->u.pirq.pirq] = -1;
755 irq_info[irq] = mk_unbound_info();
760 spin_unlock(&irq_mapping_update_lock);
764 int xen_vector_from_irq(unsigned irq)
766 return vector_from_irq(irq);
769 int xen_gsi_from_irq(unsigned irq)
771 return gsi_from_irq(irq);
774 int xen_irq_from_pirq(unsigned pirq)
776 return pirq_to_irq[pirq];
779 int bind_evtchn_to_irq(unsigned int evtchn)
783 spin_lock(&irq_mapping_update_lock);
785 irq = evtchn_to_irq[evtchn];
788 irq = xen_allocate_irq_dynamic();
790 set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
791 handle_fasteoi_irq, "event");
793 evtchn_to_irq[evtchn] = irq;
794 irq_info[irq] = mk_evtchn_info(evtchn);
797 spin_unlock(&irq_mapping_update_lock);
801 EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
803 static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
805 struct evtchn_bind_ipi bind_ipi;
808 spin_lock(&irq_mapping_update_lock);
810 irq = per_cpu(ipi_to_irq, cpu)[ipi];
813 irq = xen_allocate_irq_dynamic();
817 set_irq_chip_and_handler_name(irq, &xen_percpu_chip,
818 handle_percpu_irq, "ipi");
821 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
824 evtchn = bind_ipi.port;
826 evtchn_to_irq[evtchn] = irq;
827 irq_info[irq] = mk_ipi_info(evtchn, ipi);
828 per_cpu(ipi_to_irq, cpu)[ipi] = irq;
830 bind_evtchn_to_cpu(evtchn, cpu);
834 spin_unlock(&irq_mapping_update_lock);
839 int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
841 struct evtchn_bind_virq bind_virq;
844 spin_lock(&irq_mapping_update_lock);
846 irq = per_cpu(virq_to_irq, cpu)[virq];
849 irq = xen_allocate_irq_dynamic();
851 set_irq_chip_and_handler_name(irq, &xen_percpu_chip,
852 handle_percpu_irq, "virq");
854 bind_virq.virq = virq;
855 bind_virq.vcpu = cpu;
856 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
859 evtchn = bind_virq.port;
861 evtchn_to_irq[evtchn] = irq;
862 irq_info[irq] = mk_virq_info(evtchn, virq);
864 per_cpu(virq_to_irq, cpu)[virq] = irq;
866 bind_evtchn_to_cpu(evtchn, cpu);
869 spin_unlock(&irq_mapping_update_lock);
874 static void unbind_from_irq(unsigned int irq)
876 struct evtchn_close close;
877 int evtchn = evtchn_from_irq(irq);
879 spin_lock(&irq_mapping_update_lock);
881 if (VALID_EVTCHN(evtchn)) {
883 if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
886 switch (type_from_irq(irq)) {
888 per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
889 [virq_from_irq(irq)] = -1;
892 per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
893 [ipi_from_irq(irq)] = -1;
899 /* Closed ports are implicitly re-bound to VCPU0. */
900 bind_evtchn_to_cpu(evtchn, 0);
902 evtchn_to_irq[evtchn] = -1;
905 if (irq_info[irq].type != IRQT_UNBOUND) {
906 irq_info[irq] = mk_unbound_info();
911 spin_unlock(&irq_mapping_update_lock);
914 int bind_evtchn_to_irqhandler(unsigned int evtchn,
915 irq_handler_t handler,
916 unsigned long irqflags,
917 const char *devname, void *dev_id)
922 irq = bind_evtchn_to_irq(evtchn);
923 retval = request_irq(irq, handler, irqflags, devname, dev_id);
925 unbind_from_irq(irq);
931 EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler);
933 int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
934 irq_handler_t handler,
935 unsigned long irqflags, const char *devname, void *dev_id)
940 irq = bind_virq_to_irq(virq, cpu);
941 retval = request_irq(irq, handler, irqflags, devname, dev_id);
943 unbind_from_irq(irq);
949 EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);
951 int bind_ipi_to_irqhandler(enum ipi_vector ipi,
953 irq_handler_t handler,
954 unsigned long irqflags,
960 irq = bind_ipi_to_irq(ipi, cpu);
964 irqflags |= IRQF_NO_SUSPEND | IRQF_FORCE_RESUME;
965 retval = request_irq(irq, handler, irqflags, devname, dev_id);
967 unbind_from_irq(irq);
974 void unbind_from_irqhandler(unsigned int irq, void *dev_id)
976 free_irq(irq, dev_id);
977 unbind_from_irq(irq);
979 EXPORT_SYMBOL_GPL(unbind_from_irqhandler);
981 void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
983 int irq = per_cpu(ipi_to_irq, cpu)[vector];
985 notify_remote_via_irq(irq);
988 irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
990 struct shared_info *sh = HYPERVISOR_shared_info;
991 int cpu = smp_processor_id();
992 unsigned long *cpu_evtchn = cpu_evtchn_mask(cpu);
995 static DEFINE_SPINLOCK(debug_lock);
998 spin_lock_irqsave(&debug_lock, flags);
1000 printk("\nvcpu %d\n ", cpu);
1002 for_each_online_cpu(i) {
1004 v = per_cpu(xen_vcpu, i);
1005 pending = (get_irq_regs() && i == cpu)
1006 ? xen_irqs_disabled(get_irq_regs())
1007 : v->evtchn_upcall_mask;
1008 printk("%d: masked=%d pending=%d event_sel %0*lx\n ", i,
1009 pending, v->evtchn_upcall_pending,
1010 (int)(sizeof(v->evtchn_pending_sel)*2),
1011 v->evtchn_pending_sel);
1013 v = per_cpu(xen_vcpu, cpu);
1015 printk("\npending:\n ");
1016 for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--)
1017 printk("%0*lx%s", (int)sizeof(sh->evtchn_pending[0])*2,
1018 sh->evtchn_pending[i],
1019 i % 8 == 0 ? "\n " : " ");
1020 printk("\nglobal mask:\n ");
1021 for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
1023 (int)(sizeof(sh->evtchn_mask[0])*2),
1025 i % 8 == 0 ? "\n " : " ");
1027 printk("\nglobally unmasked:\n ");
1028 for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
1029 printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
1030 sh->evtchn_pending[i] & ~sh->evtchn_mask[i],
1031 i % 8 == 0 ? "\n " : " ");
1033 printk("\nlocal cpu%d mask:\n ", cpu);
1034 for (i = (NR_EVENT_CHANNELS/BITS_PER_LONG)-1; i >= 0; i--)
1035 printk("%0*lx%s", (int)(sizeof(cpu_evtchn[0])*2),
1037 i % 8 == 0 ? "\n " : " ");
1039 printk("\nlocally unmasked:\n ");
1040 for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) {
1041 unsigned long pending = sh->evtchn_pending[i]
1042 & ~sh->evtchn_mask[i]
1044 printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
1045 pending, i % 8 == 0 ? "\n " : " ");
1048 printk("\npending list:\n");
1049 for (i = 0; i < NR_EVENT_CHANNELS; i++) {
1050 if (sync_test_bit(i, sh->evtchn_pending)) {
1051 int word_idx = i / BITS_PER_LONG;
1052 printk(" %d: event %d -> irq %d%s%s%s\n",
1053 cpu_from_evtchn(i), i,
1055 sync_test_bit(word_idx, &v->evtchn_pending_sel)
1057 !sync_test_bit(i, sh->evtchn_mask)
1058 ? "" : " globally-masked",
1059 sync_test_bit(i, cpu_evtchn)
1060 ? "" : " locally-masked");
1064 spin_unlock_irqrestore(&debug_lock, flags);
1069 static DEFINE_PER_CPU(unsigned, xed_nesting_count);
1072 * Search the CPUs pending events bitmasks. For each one found, map
1073 * the event number to an irq, and feed it into do_IRQ() for
1076 * Xen uses a two-level bitmap to speed searching. The first level is
1077 * a bitset of words which contain pending event bits. The second
1078 * level is a bitset of pending events themselves.
1080 static void __xen_evtchn_do_upcall(void)
1082 int cpu = get_cpu();
1083 struct shared_info *s = HYPERVISOR_shared_info;
1084 struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
1088 unsigned long pending_words;
1090 vcpu_info->evtchn_upcall_pending = 0;
1092 if (__this_cpu_inc_return(xed_nesting_count) - 1)
1095 #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
1096 /* Clear master flag /before/ clearing selector flag. */
1099 pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
1100 while (pending_words != 0) {
1101 unsigned long pending_bits;
1102 int word_idx = __ffs(pending_words);
1103 pending_words &= ~(1UL << word_idx);
1105 while ((pending_bits = active_evtchns(cpu, s, word_idx)) != 0) {
1106 int bit_idx = __ffs(pending_bits);
1107 int port = (word_idx * BITS_PER_LONG) + bit_idx;
1108 int irq = evtchn_to_irq[port];
1109 struct irq_desc *desc;
1115 desc = irq_to_desc(irq);
1117 generic_handle_irq_desc(irq, desc);
1122 BUG_ON(!irqs_disabled());
1124 count = __this_cpu_read(xed_nesting_count);
1125 __this_cpu_write(xed_nesting_count, 0);
1126 } while (count != 1 || vcpu_info->evtchn_upcall_pending);
1133 void xen_evtchn_do_upcall(struct pt_regs *regs)
1135 struct pt_regs *old_regs = set_irq_regs(regs);
1140 __xen_evtchn_do_upcall();
1143 set_irq_regs(old_regs);
1146 void xen_hvm_evtchn_do_upcall(void)
1148 __xen_evtchn_do_upcall();
1150 EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall);
1152 /* Rebind a new event channel to an existing irq. */
1153 void rebind_evtchn_irq(int evtchn, int irq)
1155 struct irq_info *info = info_for_irq(irq);
1157 /* Make sure the irq is masked, since the new event channel
1158 will also be masked. */
1161 spin_lock(&irq_mapping_update_lock);
1163 /* After resume the irq<->evtchn mappings are all cleared out */
1164 BUG_ON(evtchn_to_irq[evtchn] != -1);
1165 /* Expect irq to have been bound before,
1166 so there should be a proper type */
1167 BUG_ON(info->type == IRQT_UNBOUND);
1169 evtchn_to_irq[evtchn] = irq;
1170 irq_info[irq] = mk_evtchn_info(evtchn);
1172 spin_unlock(&irq_mapping_update_lock);
1174 /* new event channels are always bound to cpu 0 */
1175 irq_set_affinity(irq, cpumask_of(0));
1177 /* Unmask the event channel. */
1181 /* Rebind an evtchn so that it gets delivered to a specific cpu */
1182 static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
1184 struct evtchn_bind_vcpu bind_vcpu;
1185 int evtchn = evtchn_from_irq(irq);
1187 /* events delivered via platform PCI interrupts are always
1188 * routed to vcpu 0 */
1189 if (!VALID_EVTCHN(evtchn) ||
1190 (xen_hvm_domain() && !xen_have_vector_callback))
1193 /* Send future instances of this interrupt to other vcpu. */
1194 bind_vcpu.port = evtchn;
1195 bind_vcpu.vcpu = tcpu;
1198 * If this fails, it usually just indicates that we're dealing with a
1199 * virq or IPI channel, which don't actually need to be rebound. Ignore
1200 * it, but don't do the xenlinux-level rebind in that case.
1202 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
1203 bind_evtchn_to_cpu(evtchn, tcpu);
1208 static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest,
1211 unsigned tcpu = cpumask_first(dest);
1213 return rebind_irq_to_cpu(data->irq, tcpu);
1216 int resend_irq_on_evtchn(unsigned int irq)
1218 int masked, evtchn = evtchn_from_irq(irq);
1219 struct shared_info *s = HYPERVISOR_shared_info;
1221 if (!VALID_EVTCHN(evtchn))
1224 masked = sync_test_and_set_bit(evtchn, s->evtchn_mask);
1225 sync_set_bit(evtchn, s->evtchn_pending);
1227 unmask_evtchn(evtchn);
1232 static void enable_dynirq(struct irq_data *data)
1234 int evtchn = evtchn_from_irq(data->irq);
1236 if (VALID_EVTCHN(evtchn))
1237 unmask_evtchn(evtchn);
1240 static void disable_dynirq(struct irq_data *data)
1242 int evtchn = evtchn_from_irq(data->irq);
1244 if (VALID_EVTCHN(evtchn))
1245 mask_evtchn(evtchn);
1248 static void ack_dynirq(struct irq_data *data)
1250 int evtchn = evtchn_from_irq(data->irq);
1252 move_masked_irq(data->irq);
1254 if (VALID_EVTCHN(evtchn))
1255 unmask_evtchn(evtchn);
1258 static int retrigger_dynirq(struct irq_data *data)
1260 int evtchn = evtchn_from_irq(data->irq);
1261 struct shared_info *sh = HYPERVISOR_shared_info;
1264 if (VALID_EVTCHN(evtchn)) {
1267 masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask);
1268 sync_set_bit(evtchn, sh->evtchn_pending);
1270 unmask_evtchn(evtchn);
1277 static void restore_cpu_pirqs(void)
1279 int pirq, rc, irq, gsi;
1280 struct physdev_map_pirq map_irq;
1282 for (pirq = 0; pirq < nr_irqs; pirq++) {
1283 irq = pirq_to_irq[pirq];
1287 /* save/restore of PT devices doesn't work, so at this point the
1288 * only devices present are GSI based emulated devices */
1289 gsi = gsi_from_irq(irq);
1293 map_irq.domid = DOMID_SELF;
1294 map_irq.type = MAP_PIRQ_TYPE_GSI;
1295 map_irq.index = gsi;
1296 map_irq.pirq = pirq;
1298 rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
1300 printk(KERN_WARNING "xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
1301 gsi, irq, pirq, rc);
1302 irq_info[irq] = mk_unbound_info();
1303 pirq_to_irq[pirq] = -1;
1307 printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
1309 __startup_pirq(irq);
1313 static void restore_cpu_virqs(unsigned int cpu)
1315 struct evtchn_bind_virq bind_virq;
1316 int virq, irq, evtchn;
1318 for (virq = 0; virq < NR_VIRQS; virq++) {
1319 if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1)
1322 BUG_ON(virq_from_irq(irq) != virq);
1324 /* Get a new binding from Xen. */
1325 bind_virq.virq = virq;
1326 bind_virq.vcpu = cpu;
1327 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
1330 evtchn = bind_virq.port;
1332 /* Record the new mapping. */
1333 evtchn_to_irq[evtchn] = irq;
1334 irq_info[irq] = mk_virq_info(evtchn, virq);
1335 bind_evtchn_to_cpu(evtchn, cpu);
1339 static void restore_cpu_ipis(unsigned int cpu)
1341 struct evtchn_bind_ipi bind_ipi;
1342 int ipi, irq, evtchn;
1344 for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) {
1345 if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1)
1348 BUG_ON(ipi_from_irq(irq) != ipi);
1350 /* Get a new binding from Xen. */
1351 bind_ipi.vcpu = cpu;
1352 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
1355 evtchn = bind_ipi.port;
1357 /* Record the new mapping. */
1358 evtchn_to_irq[evtchn] = irq;
1359 irq_info[irq] = mk_ipi_info(evtchn, ipi);
1360 bind_evtchn_to_cpu(evtchn, cpu);
1364 /* Clear an irq's pending state, in preparation for polling on it */
1365 void xen_clear_irq_pending(int irq)
1367 int evtchn = evtchn_from_irq(irq);
1369 if (VALID_EVTCHN(evtchn))
1370 clear_evtchn(evtchn);
1372 EXPORT_SYMBOL(xen_clear_irq_pending);
1373 void xen_set_irq_pending(int irq)
1375 int evtchn = evtchn_from_irq(irq);
1377 if (VALID_EVTCHN(evtchn))
1381 bool xen_test_irq_pending(int irq)
1383 int evtchn = evtchn_from_irq(irq);
1386 if (VALID_EVTCHN(evtchn))
1387 ret = test_evtchn(evtchn);
1392 /* Poll waiting for an irq to become pending with timeout. In the usual case,
1393 * the irq will be disabled so it won't deliver an interrupt. */
1394 void xen_poll_irq_timeout(int irq, u64 timeout)
1396 evtchn_port_t evtchn = evtchn_from_irq(irq);
1398 if (VALID_EVTCHN(evtchn)) {
1399 struct sched_poll poll;
1402 poll.timeout = timeout;
1403 set_xen_guest_handle(poll.ports, &evtchn);
1405 if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
1409 EXPORT_SYMBOL(xen_poll_irq_timeout);
1410 /* Poll waiting for an irq to become pending. In the usual case, the
1411 * irq will be disabled so it won't deliver an interrupt. */
1412 void xen_poll_irq(int irq)
1414 xen_poll_irq_timeout(irq, 0 /* no timeout */);
1417 void xen_irq_resume(void)
1419 unsigned int cpu, irq, evtchn;
1421 init_evtchn_cpu_bindings();
1423 /* New event-channel space is not 'live' yet. */
1424 for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
1425 mask_evtchn(evtchn);
1427 /* No IRQ <-> event-channel mappings. */
1428 for (irq = 0; irq < nr_irqs; irq++)
1429 irq_info[irq].evtchn = 0; /* zap event-channel binding */
1431 for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
1432 evtchn_to_irq[evtchn] = -1;
1434 for_each_possible_cpu(cpu) {
1435 restore_cpu_virqs(cpu);
1436 restore_cpu_ipis(cpu);
1439 restore_cpu_pirqs();
1442 static struct irq_chip xen_dynamic_chip __read_mostly = {
1445 .irq_disable = disable_dynirq,
1446 .irq_mask = disable_dynirq,
1447 .irq_unmask = enable_dynirq,
1449 .irq_eoi = ack_dynirq,
1450 .irq_set_affinity = set_affinity_irq,
1451 .irq_retrigger = retrigger_dynirq,
1454 static struct irq_chip xen_pirq_chip __read_mostly = {
1457 .irq_startup = startup_pirq,
1458 .irq_shutdown = shutdown_pirq,
1460 .irq_enable = enable_pirq,
1461 .irq_unmask = enable_pirq,
1463 .irq_disable = disable_pirq,
1464 .irq_mask = disable_pirq,
1466 .irq_ack = ack_pirq,
1468 .irq_set_affinity = set_affinity_irq,
1470 .irq_retrigger = retrigger_dynirq,
1473 static struct irq_chip xen_percpu_chip __read_mostly = {
1474 .name = "xen-percpu",
1476 .irq_disable = disable_dynirq,
1477 .irq_mask = disable_dynirq,
1478 .irq_unmask = enable_dynirq,
1480 .irq_ack = ack_dynirq,
1483 int xen_set_callback_via(uint64_t via)
1485 struct xen_hvm_param a;
1486 a.domid = DOMID_SELF;
1487 a.index = HVM_PARAM_CALLBACK_IRQ;
1489 return HYPERVISOR_hvm_op(HVMOP_set_param, &a);
1491 EXPORT_SYMBOL_GPL(xen_set_callback_via);
1493 #ifdef CONFIG_XEN_PVHVM
1494 /* Vector callbacks are better than PCI interrupts to receive event
1495 * channel notifications because we can receive vector callbacks on any
1496 * vcpu and we don't need PCI support or APIC interactions. */
1497 void xen_callback_vector(void)
1500 uint64_t callback_via;
1501 if (xen_have_vector_callback) {
1502 callback_via = HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK);
1503 rc = xen_set_callback_via(callback_via);
1505 printk(KERN_ERR "Request for Xen HVM callback vector"
1507 xen_have_vector_callback = 0;
1510 printk(KERN_INFO "Xen HVM callback vector for event delivery is "
1512 /* in the restore case the vector has already been allocated */
1513 if (!test_bit(XEN_HVM_EVTCHN_CALLBACK, used_vectors))
1514 alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK, xen_hvm_callback_vector);
1518 void xen_callback_vector(void) {}
1521 void __init xen_init_IRQ(void)
1525 cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s),
1527 irq_info = kcalloc(nr_irqs, sizeof(*irq_info), GFP_KERNEL);
1529 /* We are using nr_irqs as the maximum number of pirq available but
1530 * that number is actually chosen by Xen and we don't know exactly
1531 * what it is. Be careful choosing high pirq numbers. */
1532 pirq_to_irq = kcalloc(nr_irqs, sizeof(*pirq_to_irq), GFP_KERNEL);
1533 for (i = 0; i < nr_irqs; i++)
1534 pirq_to_irq[i] = -1;
1536 evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
1538 for (i = 0; i < NR_EVENT_CHANNELS; i++)
1539 evtchn_to_irq[i] = -1;
1541 init_evtchn_cpu_bindings();
1543 /* No event channels are 'live' right now. */
1544 for (i = 0; i < NR_EVENT_CHANNELS; i++)
1547 if (xen_hvm_domain()) {
1548 xen_callback_vector();
1550 /* pci_xen_hvm_init must be called after native_init_IRQ so that
1551 * __acpi_register_gsi can point at the right function */
1554 irq_ctx_init(smp_processor_id());
1555 if (xen_initial_domain())