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 static LIST_HEAD(xen_irq_list_head
);
61 /* IRQ <-> VIRQ mapping. */
62 static DEFINE_PER_CPU(int [NR_VIRQS
], virq_to_irq
) = {[0 ... NR_VIRQS
-1] = -1};
64 /* IRQ <-> IPI mapping */
65 static DEFINE_PER_CPU(int [XEN_NR_IPIS
], ipi_to_irq
) = {[0 ... XEN_NR_IPIS
-1] = -1};
67 /* Interrupt types. */
77 * Packed IRQ information:
78 * type - enum xen_irq_type
79 * event channel - irq->event channel mapping
80 * cpu - cpu this event channel is bound to
81 * index - type-specific information:
82 * PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM
83 * guest, or GSI (real passthrough IRQ) of the device.
90 struct list_head list
;
91 enum xen_irq_type type
; /* type */
93 unsigned short evtchn
; /* event channel */
94 unsigned short cpu
; /* cpu bound */
102 unsigned char vector
;
107 #define PIRQ_NEEDS_EOI (1 << 0)
108 #define PIRQ_SHAREABLE (1 << 1)
110 static int *evtchn_to_irq
;
112 static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS
/BITS_PER_LONG
],
115 /* Xen will never allocate port zero for any purpose. */
116 #define VALID_EVTCHN(chn) ((chn) != 0)
118 static struct irq_chip xen_dynamic_chip
;
119 static struct irq_chip xen_percpu_chip
;
120 static struct irq_chip xen_pirq_chip
;
122 /* Get info for IRQ */
123 static struct irq_info
*info_for_irq(unsigned irq
)
125 return get_irq_data(irq
);
128 /* Constructors for packed IRQ information. */
129 static void xen_irq_info_common_init(struct irq_info
*info
,
131 enum xen_irq_type type
,
132 unsigned short evtchn
,
136 BUG_ON(info
->type
!= IRQT_UNBOUND
&& info
->type
!= type
);
140 info
->evtchn
= evtchn
;
143 evtchn_to_irq
[evtchn
] = irq
;
146 static void xen_irq_info_evtchn_init(unsigned irq
,
147 unsigned short evtchn
)
149 struct irq_info
*info
= info_for_irq(irq
);
151 xen_irq_info_common_init(info
, irq
, IRQT_EVTCHN
, evtchn
, 0);
154 static void xen_irq_info_ipi_init(unsigned cpu
,
156 unsigned short evtchn
,
159 struct irq_info
*info
= info_for_irq(irq
);
161 xen_irq_info_common_init(info
, irq
, IRQT_IPI
, evtchn
, 0);
165 per_cpu(ipi_to_irq
, cpu
)[ipi
] = irq
;
168 static void xen_irq_info_virq_init(unsigned cpu
,
170 unsigned short evtchn
,
173 struct irq_info
*info
= info_for_irq(irq
);
175 xen_irq_info_common_init(info
, irq
, IRQT_VIRQ
, evtchn
, 0);
179 per_cpu(virq_to_irq
, cpu
)[virq
] = irq
;
182 static void xen_irq_info_pirq_init(unsigned irq
,
183 unsigned short evtchn
,
186 unsigned short vector
,
189 struct irq_info
*info
= info_for_irq(irq
);
191 xen_irq_info_common_init(info
, irq
, IRQT_PIRQ
, evtchn
, 0);
193 info
->u
.pirq
.pirq
= pirq
;
194 info
->u
.pirq
.gsi
= gsi
;
195 info
->u
.pirq
.vector
= vector
;
196 info
->u
.pirq
.flags
= flags
;
200 * Accessors for packed IRQ information.
202 static unsigned int evtchn_from_irq(unsigned irq
)
204 if (unlikely(WARN(irq
< 0 || irq
>= nr_irqs
, "Invalid irq %d!\n", irq
)))
207 return info_for_irq(irq
)->evtchn
;
210 unsigned irq_from_evtchn(unsigned int evtchn
)
212 return evtchn_to_irq
[evtchn
];
214 EXPORT_SYMBOL_GPL(irq_from_evtchn
);
216 static enum ipi_vector
ipi_from_irq(unsigned irq
)
218 struct irq_info
*info
= info_for_irq(irq
);
220 BUG_ON(info
== NULL
);
221 BUG_ON(info
->type
!= IRQT_IPI
);
226 static unsigned virq_from_irq(unsigned irq
)
228 struct irq_info
*info
= info_for_irq(irq
);
230 BUG_ON(info
== NULL
);
231 BUG_ON(info
->type
!= IRQT_VIRQ
);
236 static unsigned pirq_from_irq(unsigned irq
)
238 struct irq_info
*info
= info_for_irq(irq
);
240 BUG_ON(info
== NULL
);
241 BUG_ON(info
->type
!= IRQT_PIRQ
);
243 return info
->u
.pirq
.pirq
;
246 static enum xen_irq_type
type_from_irq(unsigned irq
)
248 return info_for_irq(irq
)->type
;
251 static unsigned cpu_from_irq(unsigned irq
)
253 return info_for_irq(irq
)->cpu
;
256 static unsigned int cpu_from_evtchn(unsigned int evtchn
)
258 int irq
= evtchn_to_irq
[evtchn
];
262 ret
= cpu_from_irq(irq
);
267 static bool pirq_needs_eoi(unsigned irq
)
269 struct irq_info
*info
= info_for_irq(irq
);
271 BUG_ON(info
->type
!= IRQT_PIRQ
);
273 return info
->u
.pirq
.flags
& PIRQ_NEEDS_EOI
;
276 static inline unsigned long active_evtchns(unsigned int cpu
,
277 struct shared_info
*sh
,
280 return (sh
->evtchn_pending
[idx
] &
281 per_cpu(cpu_evtchn_mask
, cpu
)[idx
] &
282 ~sh
->evtchn_mask
[idx
]);
285 static void bind_evtchn_to_cpu(unsigned int chn
, unsigned int cpu
)
287 int irq
= evtchn_to_irq
[chn
];
291 cpumask_copy(irq_to_desc(irq
)->irq_data
.affinity
, cpumask_of(cpu
));
294 clear_bit(chn
, per_cpu(cpu_evtchn_mask
, cpu_from_irq(irq
)));
295 set_bit(chn
, per_cpu(cpu_evtchn_mask
, cpu
));
297 info_for_irq(irq
)->cpu
= cpu
;
300 static void init_evtchn_cpu_bindings(void)
304 struct irq_info
*info
;
306 /* By default all event channels notify CPU#0. */
307 list_for_each_entry(info
, &xen_irq_list_head
, list
) {
308 struct irq_desc
*desc
= irq_to_desc(info
->irq
);
309 cpumask_copy(desc
->irq_data
.affinity
, cpumask_of(0));
313 for_each_possible_cpu(i
)
314 memset(per_cpu(cpu_evtchn_mask
, i
),
315 (i
== 0) ? ~0 : 0, sizeof(*per_cpu(cpu_evtchn_mask
, i
)));
318 static inline void clear_evtchn(int port
)
320 struct shared_info
*s
= HYPERVISOR_shared_info
;
321 sync_clear_bit(port
, &s
->evtchn_pending
[0]);
324 static inline void set_evtchn(int port
)
326 struct shared_info
*s
= HYPERVISOR_shared_info
;
327 sync_set_bit(port
, &s
->evtchn_pending
[0]);
330 static inline int test_evtchn(int port
)
332 struct shared_info
*s
= HYPERVISOR_shared_info
;
333 return sync_test_bit(port
, &s
->evtchn_pending
[0]);
338 * notify_remote_via_irq - send event to remote end of event channel via irq
339 * @irq: irq of event channel to send event to
341 * Unlike notify_remote_via_evtchn(), this is safe to use across
342 * save/restore. Notifications on a broken connection are silently
345 void notify_remote_via_irq(int irq
)
347 int evtchn
= evtchn_from_irq(irq
);
349 if (VALID_EVTCHN(evtchn
))
350 notify_remote_via_evtchn(evtchn
);
352 EXPORT_SYMBOL_GPL(notify_remote_via_irq
);
354 static void mask_evtchn(int port
)
356 struct shared_info
*s
= HYPERVISOR_shared_info
;
357 sync_set_bit(port
, &s
->evtchn_mask
[0]);
360 static void unmask_evtchn(int port
)
362 struct shared_info
*s
= HYPERVISOR_shared_info
;
363 unsigned int cpu
= get_cpu();
365 BUG_ON(!irqs_disabled());
367 /* Slow path (hypercall) if this is a non-local port. */
368 if (unlikely(cpu
!= cpu_from_evtchn(port
))) {
369 struct evtchn_unmask unmask
= { .port
= port
};
370 (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask
, &unmask
);
372 struct vcpu_info
*vcpu_info
= __this_cpu_read(xen_vcpu
);
374 sync_clear_bit(port
, &s
->evtchn_mask
[0]);
377 * The following is basically the equivalent of
378 * 'hw_resend_irq'. Just like a real IO-APIC we 'lose
379 * the interrupt edge' if the channel is masked.
381 if (sync_test_bit(port
, &s
->evtchn_pending
[0]) &&
382 !sync_test_and_set_bit(port
/ BITS_PER_LONG
,
383 &vcpu_info
->evtchn_pending_sel
))
384 vcpu_info
->evtchn_upcall_pending
= 1;
390 static void xen_irq_init(unsigned irq
)
392 struct irq_info
*info
;
393 struct irq_desc
*desc
= irq_to_desc(irq
);
395 /* By default all event channels notify CPU#0. */
396 cpumask_copy(desc
->irq_data
.affinity
, cpumask_of(0));
398 info
= kzalloc(sizeof(*info
), GFP_KERNEL
);
400 panic("Unable to allocate metadata for IRQ%d\n", irq
);
402 info
->type
= IRQT_UNBOUND
;
404 set_irq_data(irq
, info
);
406 list_add_tail(&info
->list
, &xen_irq_list_head
);
409 static int __must_check
xen_allocate_irq_dynamic(void)
414 #ifdef CONFIG_X86_IO_APIC
416 * For an HVM guest or domain 0 which see "real" (emulated or
417 * actual repectively) GSIs we allocate dynamic IRQs
418 * e.g. those corresponding to event channels or MSIs
419 * etc. from the range above those "real" GSIs to avoid
422 if (xen_initial_domain() || xen_hvm_domain())
423 first
= get_nr_irqs_gsi();
426 irq
= irq_alloc_desc_from(first
, -1);
433 static int __must_check
xen_allocate_irq_gsi(unsigned gsi
)
438 * A PV guest has no concept of a GSI (since it has no ACPI
439 * nor access to/knowledge of the physical APICs). Therefore
440 * all IRQs are dynamically allocated from the entire IRQ
443 if (xen_pv_domain() && !xen_initial_domain())
444 return xen_allocate_irq_dynamic();
446 /* Legacy IRQ descriptors are already allocated by the arch. */
447 if (gsi
< NR_IRQS_LEGACY
)
450 irq
= irq_alloc_desc_at(gsi
, -1);
457 static void xen_free_irq(unsigned irq
)
459 struct irq_info
*info
= get_irq_data(irq
);
461 list_del(&info
->list
);
463 set_irq_data(irq
, NULL
);
467 /* Legacy IRQ descriptors are managed by the arch. */
468 if (irq
< NR_IRQS_LEGACY
)
474 static void pirq_unmask_notify(int irq
)
476 struct physdev_eoi eoi
= { .irq
= pirq_from_irq(irq
) };
478 if (unlikely(pirq_needs_eoi(irq
))) {
479 int rc
= HYPERVISOR_physdev_op(PHYSDEVOP_eoi
, &eoi
);
484 static void pirq_query_unmask(int irq
)
486 struct physdev_irq_status_query irq_status
;
487 struct irq_info
*info
= info_for_irq(irq
);
489 BUG_ON(info
->type
!= IRQT_PIRQ
);
491 irq_status
.irq
= pirq_from_irq(irq
);
492 if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query
, &irq_status
))
493 irq_status
.flags
= 0;
495 info
->u
.pirq
.flags
&= ~PIRQ_NEEDS_EOI
;
496 if (irq_status
.flags
& XENIRQSTAT_needs_eoi
)
497 info
->u
.pirq
.flags
|= PIRQ_NEEDS_EOI
;
500 static bool probing_irq(int irq
)
502 struct irq_desc
*desc
= irq_to_desc(irq
);
504 return desc
&& desc
->action
== NULL
;
507 static unsigned int __startup_pirq(unsigned int irq
)
509 struct evtchn_bind_pirq bind_pirq
;
510 struct irq_info
*info
= info_for_irq(irq
);
511 int evtchn
= evtchn_from_irq(irq
);
514 BUG_ON(info
->type
!= IRQT_PIRQ
);
516 if (VALID_EVTCHN(evtchn
))
519 bind_pirq
.pirq
= pirq_from_irq(irq
);
520 /* NB. We are happy to share unless we are probing. */
521 bind_pirq
.flags
= info
->u
.pirq
.flags
& PIRQ_SHAREABLE
?
522 BIND_PIRQ__WILL_SHARE
: 0;
523 rc
= HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq
, &bind_pirq
);
525 if (!probing_irq(irq
))
526 printk(KERN_INFO
"Failed to obtain physical IRQ %d\n",
530 evtchn
= bind_pirq
.port
;
532 pirq_query_unmask(irq
);
534 evtchn_to_irq
[evtchn
] = irq
;
535 bind_evtchn_to_cpu(evtchn
, 0);
536 info
->evtchn
= evtchn
;
539 unmask_evtchn(evtchn
);
540 pirq_unmask_notify(irq
);
545 static unsigned int startup_pirq(struct irq_data
*data
)
547 return __startup_pirq(data
->irq
);
550 static void shutdown_pirq(struct irq_data
*data
)
552 struct evtchn_close close
;
553 unsigned int irq
= data
->irq
;
554 struct irq_info
*info
= info_for_irq(irq
);
555 int evtchn
= evtchn_from_irq(irq
);
557 BUG_ON(info
->type
!= IRQT_PIRQ
);
559 if (!VALID_EVTCHN(evtchn
))
565 if (HYPERVISOR_event_channel_op(EVTCHNOP_close
, &close
) != 0)
568 bind_evtchn_to_cpu(evtchn
, 0);
569 evtchn_to_irq
[evtchn
] = -1;
573 static void enable_pirq(struct irq_data
*data
)
578 static void disable_pirq(struct irq_data
*data
)
582 static void ack_pirq(struct irq_data
*data
)
584 int evtchn
= evtchn_from_irq(data
->irq
);
586 move_native_irq(data
->irq
);
588 if (VALID_EVTCHN(evtchn
)) {
590 clear_evtchn(evtchn
);
594 static int find_irq_by_gsi(unsigned gsi
)
596 struct irq_info
*info
;
598 list_for_each_entry(info
, &xen_irq_list_head
, list
) {
599 if (info
->type
!= IRQT_PIRQ
)
602 if (info
->u
.pirq
.gsi
== gsi
)
609 int xen_allocate_pirq_gsi(unsigned gsi
)
615 * Do not make any assumptions regarding the relationship between the
616 * IRQ number returned here and the Xen pirq argument.
618 * Note: We don't assign an event channel until the irq actually started
619 * up. Return an existing irq if we've already got one for the gsi.
621 int xen_bind_pirq_gsi_to_irq(unsigned gsi
,
622 unsigned pirq
, int shareable
, char *name
)
625 struct physdev_irq irq_op
;
627 spin_lock(&irq_mapping_update_lock
);
629 irq
= find_irq_by_gsi(gsi
);
631 printk(KERN_INFO
"xen_map_pirq_gsi: returning irq %d for gsi %u\n",
633 goto out
; /* XXX need refcount? */
636 irq
= xen_allocate_irq_gsi(gsi
);
640 set_irq_chip_and_handler_name(irq
, &xen_pirq_chip
,
641 handle_level_irq
, name
);
646 /* Only the privileged domain can do this. For non-priv, the pcifront
647 * driver provides a PCI bus that does the call to do exactly
648 * this in the priv domain. */
649 if (xen_initial_domain() &&
650 HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector
, &irq_op
)) {
656 xen_irq_info_pirq_init(irq
, 0, pirq
, gsi
, irq_op
.vector
,
657 shareable
? PIRQ_SHAREABLE
: 0);
660 spin_unlock(&irq_mapping_update_lock
);
665 #ifdef CONFIG_PCI_MSI
666 int xen_allocate_pirq_msi(struct pci_dev
*dev
, struct msi_desc
*msidesc
)
669 struct physdev_get_free_pirq op_get_free_pirq
;
671 op_get_free_pirq
.type
= MAP_PIRQ_TYPE_MSI
;
672 rc
= HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq
, &op_get_free_pirq
);
674 WARN_ONCE(rc
== -ENOSYS
,
675 "hypervisor does not support the PHYSDEVOP_get_free_pirq interface\n");
677 return rc
? -1 : op_get_free_pirq
.pirq
;
680 int xen_bind_pirq_msi_to_irq(struct pci_dev
*dev
, struct msi_desc
*msidesc
,
681 int pirq
, int vector
, const char *name
)
685 spin_lock(&irq_mapping_update_lock
);
687 irq
= xen_allocate_irq_dynamic();
691 set_irq_chip_and_handler_name(irq
, &xen_pirq_chip
,
692 handle_level_irq
, name
);
694 xen_irq_info_pirq_init(irq
, 0, pirq
, 0, vector
, 0);
695 ret
= set_irq_msi(irq
, msidesc
);
699 spin_unlock(&irq_mapping_update_lock
);
702 spin_unlock(&irq_mapping_update_lock
);
708 int xen_destroy_irq(int irq
)
710 struct irq_desc
*desc
;
711 struct physdev_unmap_pirq unmap_irq
;
712 struct irq_info
*info
= info_for_irq(irq
);
715 spin_lock(&irq_mapping_update_lock
);
717 desc
= irq_to_desc(irq
);
721 if (xen_initial_domain()) {
722 unmap_irq
.pirq
= info
->u
.pirq
.pirq
;
723 unmap_irq
.domid
= DOMID_SELF
;
724 rc
= HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq
, &unmap_irq
);
726 printk(KERN_WARNING
"unmap irq failed %d\n", rc
);
734 spin_unlock(&irq_mapping_update_lock
);
738 int xen_irq_from_pirq(unsigned pirq
)
742 struct irq_info
*info
;
744 spin_lock(&irq_mapping_update_lock
);
746 list_for_each_entry(info
, &xen_irq_list_head
, list
) {
747 if (info
== NULL
|| info
->type
!= IRQT_PIRQ
)
750 if (info
->u
.pirq
.pirq
== pirq
)
755 spin_lock(&irq_mapping_update_lock
);
760 int bind_evtchn_to_irq(unsigned int evtchn
)
764 spin_lock(&irq_mapping_update_lock
);
766 irq
= evtchn_to_irq
[evtchn
];
769 irq
= xen_allocate_irq_dynamic();
773 set_irq_chip_and_handler_name(irq
, &xen_dynamic_chip
,
774 handle_fasteoi_irq
, "event");
776 xen_irq_info_evtchn_init(irq
, evtchn
);
780 spin_unlock(&irq_mapping_update_lock
);
784 EXPORT_SYMBOL_GPL(bind_evtchn_to_irq
);
786 static int bind_ipi_to_irq(unsigned int ipi
, unsigned int cpu
)
788 struct evtchn_bind_ipi bind_ipi
;
791 spin_lock(&irq_mapping_update_lock
);
793 irq
= per_cpu(ipi_to_irq
, cpu
)[ipi
];
796 irq
= xen_allocate_irq_dynamic();
800 set_irq_chip_and_handler_name(irq
, &xen_percpu_chip
,
801 handle_percpu_irq
, "ipi");
804 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi
,
807 evtchn
= bind_ipi
.port
;
809 xen_irq_info_ipi_init(cpu
, irq
, evtchn
, ipi
);
811 bind_evtchn_to_cpu(evtchn
, cpu
);
815 spin_unlock(&irq_mapping_update_lock
);
820 int bind_virq_to_irq(unsigned int virq
, unsigned int cpu
)
822 struct evtchn_bind_virq bind_virq
;
825 spin_lock(&irq_mapping_update_lock
);
827 irq
= per_cpu(virq_to_irq
, cpu
)[virq
];
830 irq
= xen_allocate_irq_dynamic();
834 set_irq_chip_and_handler_name(irq
, &xen_percpu_chip
,
835 handle_percpu_irq
, "virq");
837 bind_virq
.virq
= virq
;
838 bind_virq
.vcpu
= cpu
;
839 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq
,
842 evtchn
= bind_virq
.port
;
844 xen_irq_info_virq_init(cpu
, irq
, evtchn
, virq
);
846 bind_evtchn_to_cpu(evtchn
, cpu
);
850 spin_unlock(&irq_mapping_update_lock
);
855 static void unbind_from_irq(unsigned int irq
)
857 struct evtchn_close close
;
858 int evtchn
= evtchn_from_irq(irq
);
860 spin_lock(&irq_mapping_update_lock
);
862 if (VALID_EVTCHN(evtchn
)) {
864 if (HYPERVISOR_event_channel_op(EVTCHNOP_close
, &close
) != 0)
867 switch (type_from_irq(irq
)) {
869 per_cpu(virq_to_irq
, cpu_from_evtchn(evtchn
))
870 [virq_from_irq(irq
)] = -1;
873 per_cpu(ipi_to_irq
, cpu_from_evtchn(evtchn
))
874 [ipi_from_irq(irq
)] = -1;
880 /* Closed ports are implicitly re-bound to VCPU0. */
881 bind_evtchn_to_cpu(evtchn
, 0);
883 evtchn_to_irq
[evtchn
] = -1;
886 BUG_ON(info_for_irq(irq
)->type
== IRQT_UNBOUND
);
890 spin_unlock(&irq_mapping_update_lock
);
893 int bind_evtchn_to_irqhandler(unsigned int evtchn
,
894 irq_handler_t handler
,
895 unsigned long irqflags
,
896 const char *devname
, void *dev_id
)
901 irq
= bind_evtchn_to_irq(evtchn
);
904 retval
= request_irq(irq
, handler
, irqflags
, devname
, dev_id
);
906 unbind_from_irq(irq
);
912 EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler
);
914 int bind_virq_to_irqhandler(unsigned int virq
, unsigned int cpu
,
915 irq_handler_t handler
,
916 unsigned long irqflags
, const char *devname
, void *dev_id
)
921 irq
= bind_virq_to_irq(virq
, cpu
);
924 retval
= request_irq(irq
, handler
, irqflags
, devname
, dev_id
);
926 unbind_from_irq(irq
);
932 EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler
);
934 int bind_ipi_to_irqhandler(enum ipi_vector ipi
,
936 irq_handler_t handler
,
937 unsigned long irqflags
,
943 irq
= bind_ipi_to_irq(ipi
, cpu
);
947 irqflags
|= IRQF_NO_SUSPEND
| IRQF_FORCE_RESUME
;
948 retval
= request_irq(irq
, handler
, irqflags
, devname
, dev_id
);
950 unbind_from_irq(irq
);
957 void unbind_from_irqhandler(unsigned int irq
, void *dev_id
)
959 free_irq(irq
, dev_id
);
960 unbind_from_irq(irq
);
962 EXPORT_SYMBOL_GPL(unbind_from_irqhandler
);
964 void xen_send_IPI_one(unsigned int cpu
, enum ipi_vector vector
)
966 int irq
= per_cpu(ipi_to_irq
, cpu
)[vector
];
968 notify_remote_via_irq(irq
);
971 irqreturn_t
xen_debug_interrupt(int irq
, void *dev_id
)
973 struct shared_info
*sh
= HYPERVISOR_shared_info
;
974 int cpu
= smp_processor_id();
975 unsigned long *cpu_evtchn
= per_cpu(cpu_evtchn_mask
, cpu
);
978 static DEFINE_SPINLOCK(debug_lock
);
981 spin_lock_irqsave(&debug_lock
, flags
);
983 printk("\nvcpu %d\n ", cpu
);
985 for_each_online_cpu(i
) {
987 v
= per_cpu(xen_vcpu
, i
);
988 pending
= (get_irq_regs() && i
== cpu
)
989 ? xen_irqs_disabled(get_irq_regs())
990 : v
->evtchn_upcall_mask
;
991 printk("%d: masked=%d pending=%d event_sel %0*lx\n ", i
,
992 pending
, v
->evtchn_upcall_pending
,
993 (int)(sizeof(v
->evtchn_pending_sel
)*2),
994 v
->evtchn_pending_sel
);
996 v
= per_cpu(xen_vcpu
, cpu
);
998 printk("\npending:\n ");
999 for (i
= ARRAY_SIZE(sh
->evtchn_pending
)-1; i
>= 0; i
--)
1000 printk("%0*lx%s", (int)sizeof(sh
->evtchn_pending
[0])*2,
1001 sh
->evtchn_pending
[i
],
1002 i
% 8 == 0 ? "\n " : " ");
1003 printk("\nglobal mask:\n ");
1004 for (i
= ARRAY_SIZE(sh
->evtchn_mask
)-1; i
>= 0; i
--)
1006 (int)(sizeof(sh
->evtchn_mask
[0])*2),
1008 i
% 8 == 0 ? "\n " : " ");
1010 printk("\nglobally unmasked:\n ");
1011 for (i
= ARRAY_SIZE(sh
->evtchn_mask
)-1; i
>= 0; i
--)
1012 printk("%0*lx%s", (int)(sizeof(sh
->evtchn_mask
[0])*2),
1013 sh
->evtchn_pending
[i
] & ~sh
->evtchn_mask
[i
],
1014 i
% 8 == 0 ? "\n " : " ");
1016 printk("\nlocal cpu%d mask:\n ", cpu
);
1017 for (i
= (NR_EVENT_CHANNELS
/BITS_PER_LONG
)-1; i
>= 0; i
--)
1018 printk("%0*lx%s", (int)(sizeof(cpu_evtchn
[0])*2),
1020 i
% 8 == 0 ? "\n " : " ");
1022 printk("\nlocally unmasked:\n ");
1023 for (i
= ARRAY_SIZE(sh
->evtchn_mask
)-1; i
>= 0; i
--) {
1024 unsigned long pending
= sh
->evtchn_pending
[i
]
1025 & ~sh
->evtchn_mask
[i
]
1027 printk("%0*lx%s", (int)(sizeof(sh
->evtchn_mask
[0])*2),
1028 pending
, i
% 8 == 0 ? "\n " : " ");
1031 printk("\npending list:\n");
1032 for (i
= 0; i
< NR_EVENT_CHANNELS
; i
++) {
1033 if (sync_test_bit(i
, sh
->evtchn_pending
)) {
1034 int word_idx
= i
/ BITS_PER_LONG
;
1035 printk(" %d: event %d -> irq %d%s%s%s\n",
1036 cpu_from_evtchn(i
), i
,
1038 sync_test_bit(word_idx
, &v
->evtchn_pending_sel
)
1040 !sync_test_bit(i
, sh
->evtchn_mask
)
1041 ? "" : " globally-masked",
1042 sync_test_bit(i
, cpu_evtchn
)
1043 ? "" : " locally-masked");
1047 spin_unlock_irqrestore(&debug_lock
, flags
);
1052 static DEFINE_PER_CPU(unsigned, xed_nesting_count
);
1055 * Search the CPUs pending events bitmasks. For each one found, map
1056 * the event number to an irq, and feed it into do_IRQ() for
1059 * Xen uses a two-level bitmap to speed searching. The first level is
1060 * a bitset of words which contain pending event bits. The second
1061 * level is a bitset of pending events themselves.
1063 static void __xen_evtchn_do_upcall(void)
1065 int cpu
= get_cpu();
1066 struct shared_info
*s
= HYPERVISOR_shared_info
;
1067 struct vcpu_info
*vcpu_info
= __this_cpu_read(xen_vcpu
);
1071 unsigned long pending_words
;
1073 vcpu_info
->evtchn_upcall_pending
= 0;
1075 if (__this_cpu_inc_return(xed_nesting_count
) - 1)
1078 #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
1079 /* Clear master flag /before/ clearing selector flag. */
1082 pending_words
= xchg(&vcpu_info
->evtchn_pending_sel
, 0);
1083 while (pending_words
!= 0) {
1084 unsigned long pending_bits
;
1085 int word_idx
= __ffs(pending_words
);
1086 pending_words
&= ~(1UL << word_idx
);
1088 while ((pending_bits
= active_evtchns(cpu
, s
, word_idx
)) != 0) {
1089 int bit_idx
= __ffs(pending_bits
);
1090 int port
= (word_idx
* BITS_PER_LONG
) + bit_idx
;
1091 int irq
= evtchn_to_irq
[port
];
1092 struct irq_desc
*desc
;
1098 desc
= irq_to_desc(irq
);
1100 generic_handle_irq_desc(irq
, desc
);
1105 BUG_ON(!irqs_disabled());
1107 count
= __this_cpu_read(xed_nesting_count
);
1108 __this_cpu_write(xed_nesting_count
, 0);
1109 } while (count
!= 1 || vcpu_info
->evtchn_upcall_pending
);
1116 void xen_evtchn_do_upcall(struct pt_regs
*regs
)
1118 struct pt_regs
*old_regs
= set_irq_regs(regs
);
1123 __xen_evtchn_do_upcall();
1126 set_irq_regs(old_regs
);
1129 void xen_hvm_evtchn_do_upcall(void)
1131 __xen_evtchn_do_upcall();
1133 EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall
);
1135 /* Rebind a new event channel to an existing irq. */
1136 void rebind_evtchn_irq(int evtchn
, int irq
)
1138 struct irq_info
*info
= info_for_irq(irq
);
1140 /* Make sure the irq is masked, since the new event channel
1141 will also be masked. */
1144 spin_lock(&irq_mapping_update_lock
);
1146 /* After resume the irq<->evtchn mappings are all cleared out */
1147 BUG_ON(evtchn_to_irq
[evtchn
] != -1);
1148 /* Expect irq to have been bound before,
1149 so there should be a proper type */
1150 BUG_ON(info
->type
== IRQT_UNBOUND
);
1152 xen_irq_info_evtchn_init(irq
, evtchn
);
1154 spin_unlock(&irq_mapping_update_lock
);
1156 /* new event channels are always bound to cpu 0 */
1157 irq_set_affinity(irq
, cpumask_of(0));
1159 /* Unmask the event channel. */
1163 /* Rebind an evtchn so that it gets delivered to a specific cpu */
1164 static int rebind_irq_to_cpu(unsigned irq
, unsigned tcpu
)
1166 struct evtchn_bind_vcpu bind_vcpu
;
1167 int evtchn
= evtchn_from_irq(irq
);
1169 if (!VALID_EVTCHN(evtchn
))
1173 * Events delivered via platform PCI interrupts are always
1174 * routed to vcpu 0 and hence cannot be rebound.
1176 if (xen_hvm_domain() && !xen_have_vector_callback
)
1179 /* Send future instances of this interrupt to other vcpu. */
1180 bind_vcpu
.port
= evtchn
;
1181 bind_vcpu
.vcpu
= tcpu
;
1184 * If this fails, it usually just indicates that we're dealing with a
1185 * virq or IPI channel, which don't actually need to be rebound. Ignore
1186 * it, but don't do the xenlinux-level rebind in that case.
1188 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu
, &bind_vcpu
) >= 0)
1189 bind_evtchn_to_cpu(evtchn
, tcpu
);
1194 static int set_affinity_irq(struct irq_data
*data
, const struct cpumask
*dest
,
1197 unsigned tcpu
= cpumask_first(dest
);
1199 return rebind_irq_to_cpu(data
->irq
, tcpu
);
1202 int resend_irq_on_evtchn(unsigned int irq
)
1204 int masked
, evtchn
= evtchn_from_irq(irq
);
1205 struct shared_info
*s
= HYPERVISOR_shared_info
;
1207 if (!VALID_EVTCHN(evtchn
))
1210 masked
= sync_test_and_set_bit(evtchn
, s
->evtchn_mask
);
1211 sync_set_bit(evtchn
, s
->evtchn_pending
);
1213 unmask_evtchn(evtchn
);
1218 static void enable_dynirq(struct irq_data
*data
)
1220 int evtchn
= evtchn_from_irq(data
->irq
);
1222 if (VALID_EVTCHN(evtchn
))
1223 unmask_evtchn(evtchn
);
1226 static void disable_dynirq(struct irq_data
*data
)
1228 int evtchn
= evtchn_from_irq(data
->irq
);
1230 if (VALID_EVTCHN(evtchn
))
1231 mask_evtchn(evtchn
);
1234 static void ack_dynirq(struct irq_data
*data
)
1236 int evtchn
= evtchn_from_irq(data
->irq
);
1238 move_masked_irq(data
->irq
);
1240 if (VALID_EVTCHN(evtchn
))
1241 unmask_evtchn(evtchn
);
1244 static int retrigger_dynirq(struct irq_data
*data
)
1246 int evtchn
= evtchn_from_irq(data
->irq
);
1247 struct shared_info
*sh
= HYPERVISOR_shared_info
;
1250 if (VALID_EVTCHN(evtchn
)) {
1253 masked
= sync_test_and_set_bit(evtchn
, sh
->evtchn_mask
);
1254 sync_set_bit(evtchn
, sh
->evtchn_pending
);
1256 unmask_evtchn(evtchn
);
1263 static void restore_pirqs(void)
1265 int pirq
, rc
, irq
, gsi
;
1266 struct physdev_map_pirq map_irq
;
1267 struct irq_info
*info
;
1269 list_for_each_entry(info
, &xen_irq_list_head
, list
) {
1270 if (info
->type
!= IRQT_PIRQ
)
1273 pirq
= info
->u
.pirq
.pirq
;
1274 gsi
= info
->u
.pirq
.gsi
;
1277 /* save/restore of PT devices doesn't work, so at this point the
1278 * only devices present are GSI based emulated devices */
1282 map_irq
.domid
= DOMID_SELF
;
1283 map_irq
.type
= MAP_PIRQ_TYPE_GSI
;
1284 map_irq
.index
= gsi
;
1285 map_irq
.pirq
= pirq
;
1287 rc
= HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq
, &map_irq
);
1289 printk(KERN_WARNING
"xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
1290 gsi
, irq
, pirq
, rc
);
1295 printk(KERN_DEBUG
"xen: --> irq=%d, pirq=%d\n", irq
, map_irq
.pirq
);
1297 __startup_pirq(irq
);
1301 static void restore_cpu_virqs(unsigned int cpu
)
1303 struct evtchn_bind_virq bind_virq
;
1304 int virq
, irq
, evtchn
;
1306 for (virq
= 0; virq
< NR_VIRQS
; virq
++) {
1307 if ((irq
= per_cpu(virq_to_irq
, cpu
)[virq
]) == -1)
1310 BUG_ON(virq_from_irq(irq
) != virq
);
1312 /* Get a new binding from Xen. */
1313 bind_virq
.virq
= virq
;
1314 bind_virq
.vcpu
= cpu
;
1315 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq
,
1318 evtchn
= bind_virq
.port
;
1320 /* Record the new mapping. */
1321 xen_irq_info_virq_init(cpu
, irq
, evtchn
, virq
);
1322 bind_evtchn_to_cpu(evtchn
, cpu
);
1326 static void restore_cpu_ipis(unsigned int cpu
)
1328 struct evtchn_bind_ipi bind_ipi
;
1329 int ipi
, irq
, evtchn
;
1331 for (ipi
= 0; ipi
< XEN_NR_IPIS
; ipi
++) {
1332 if ((irq
= per_cpu(ipi_to_irq
, cpu
)[ipi
]) == -1)
1335 BUG_ON(ipi_from_irq(irq
) != ipi
);
1337 /* Get a new binding from Xen. */
1338 bind_ipi
.vcpu
= cpu
;
1339 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi
,
1342 evtchn
= bind_ipi
.port
;
1344 /* Record the new mapping. */
1345 xen_irq_info_ipi_init(cpu
, irq
, evtchn
, ipi
);
1346 bind_evtchn_to_cpu(evtchn
, cpu
);
1350 /* Clear an irq's pending state, in preparation for polling on it */
1351 void xen_clear_irq_pending(int irq
)
1353 int evtchn
= evtchn_from_irq(irq
);
1355 if (VALID_EVTCHN(evtchn
))
1356 clear_evtchn(evtchn
);
1358 EXPORT_SYMBOL(xen_clear_irq_pending
);
1359 void xen_set_irq_pending(int irq
)
1361 int evtchn
= evtchn_from_irq(irq
);
1363 if (VALID_EVTCHN(evtchn
))
1367 bool xen_test_irq_pending(int irq
)
1369 int evtchn
= evtchn_from_irq(irq
);
1372 if (VALID_EVTCHN(evtchn
))
1373 ret
= test_evtchn(evtchn
);
1378 /* Poll waiting for an irq to become pending with timeout. In the usual case,
1379 * the irq will be disabled so it won't deliver an interrupt. */
1380 void xen_poll_irq_timeout(int irq
, u64 timeout
)
1382 evtchn_port_t evtchn
= evtchn_from_irq(irq
);
1384 if (VALID_EVTCHN(evtchn
)) {
1385 struct sched_poll poll
;
1388 poll
.timeout
= timeout
;
1389 set_xen_guest_handle(poll
.ports
, &evtchn
);
1391 if (HYPERVISOR_sched_op(SCHEDOP_poll
, &poll
) != 0)
1395 EXPORT_SYMBOL(xen_poll_irq_timeout
);
1396 /* Poll waiting for an irq to become pending. In the usual case, the
1397 * irq will be disabled so it won't deliver an interrupt. */
1398 void xen_poll_irq(int irq
)
1400 xen_poll_irq_timeout(irq
, 0 /* no timeout */);
1403 void xen_irq_resume(void)
1405 unsigned int cpu
, evtchn
;
1406 struct irq_info
*info
;
1408 init_evtchn_cpu_bindings();
1410 /* New event-channel space is not 'live' yet. */
1411 for (evtchn
= 0; evtchn
< NR_EVENT_CHANNELS
; evtchn
++)
1412 mask_evtchn(evtchn
);
1414 /* No IRQ <-> event-channel mappings. */
1415 list_for_each_entry(info
, &xen_irq_list_head
, list
)
1416 info
->evtchn
= 0; /* zap event-channel binding */
1418 for (evtchn
= 0; evtchn
< NR_EVENT_CHANNELS
; evtchn
++)
1419 evtchn_to_irq
[evtchn
] = -1;
1421 for_each_possible_cpu(cpu
) {
1422 restore_cpu_virqs(cpu
);
1423 restore_cpu_ipis(cpu
);
1429 static struct irq_chip xen_dynamic_chip __read_mostly
= {
1432 .irq_disable
= disable_dynirq
,
1433 .irq_mask
= disable_dynirq
,
1434 .irq_unmask
= enable_dynirq
,
1436 .irq_eoi
= ack_dynirq
,
1437 .irq_set_affinity
= set_affinity_irq
,
1438 .irq_retrigger
= retrigger_dynirq
,
1441 static struct irq_chip xen_pirq_chip __read_mostly
= {
1444 .irq_startup
= startup_pirq
,
1445 .irq_shutdown
= shutdown_pirq
,
1447 .irq_enable
= enable_pirq
,
1448 .irq_unmask
= enable_pirq
,
1450 .irq_disable
= disable_pirq
,
1451 .irq_mask
= disable_pirq
,
1453 .irq_ack
= ack_pirq
,
1455 .irq_set_affinity
= set_affinity_irq
,
1457 .irq_retrigger
= retrigger_dynirq
,
1460 static struct irq_chip xen_percpu_chip __read_mostly
= {
1461 .name
= "xen-percpu",
1463 .irq_disable
= disable_dynirq
,
1464 .irq_mask
= disable_dynirq
,
1465 .irq_unmask
= enable_dynirq
,
1467 .irq_ack
= ack_dynirq
,
1470 int xen_set_callback_via(uint64_t via
)
1472 struct xen_hvm_param a
;
1473 a
.domid
= DOMID_SELF
;
1474 a
.index
= HVM_PARAM_CALLBACK_IRQ
;
1476 return HYPERVISOR_hvm_op(HVMOP_set_param
, &a
);
1478 EXPORT_SYMBOL_GPL(xen_set_callback_via
);
1480 #ifdef CONFIG_XEN_PVHVM
1481 /* Vector callbacks are better than PCI interrupts to receive event
1482 * channel notifications because we can receive vector callbacks on any
1483 * vcpu and we don't need PCI support or APIC interactions. */
1484 void xen_callback_vector(void)
1487 uint64_t callback_via
;
1488 if (xen_have_vector_callback
) {
1489 callback_via
= HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK
);
1490 rc
= xen_set_callback_via(callback_via
);
1492 printk(KERN_ERR
"Request for Xen HVM callback vector"
1494 xen_have_vector_callback
= 0;
1497 printk(KERN_INFO
"Xen HVM callback vector for event delivery is "
1499 /* in the restore case the vector has already been allocated */
1500 if (!test_bit(XEN_HVM_EVTCHN_CALLBACK
, used_vectors
))
1501 alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK
, xen_hvm_callback_vector
);
1505 void xen_callback_vector(void) {}
1508 void __init
xen_init_IRQ(void)
1512 evtchn_to_irq
= kcalloc(NR_EVENT_CHANNELS
, sizeof(*evtchn_to_irq
),
1514 for (i
= 0; i
< NR_EVENT_CHANNELS
; i
++)
1515 evtchn_to_irq
[i
] = -1;
1517 init_evtchn_cpu_bindings();
1519 /* No event channels are 'live' right now. */
1520 for (i
= 0; i
< NR_EVENT_CHANNELS
; i
++)
1523 if (xen_hvm_domain()) {
1524 xen_callback_vector();
1526 /* pci_xen_hvm_init must be called after native_init_IRQ so that
1527 * __acpi_register_gsi can point at the right function */
1530 irq_ctx_init(smp_processor_id());
1531 if (xen_initial_domain())