media: ov5640: Add Omnivision OV5640 support
[linux-2.6.git] / drivers / xen / events.c
1 /*
2  * Xen event channels
3  *
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.
10  *
11  * There are four kinds of events which can be mapped to an event
12  * channel:
13  *
14  * 1. Inter-domain notifications.  This includes all the virtual
15  *    device events, since they're driven by front-ends in another domain
16  *    (typically dom0).
17  * 2. VIRQs, typically used for timers.  These are per-cpu events.
18  * 3. IPIs.
19  * 4. PIRQs - Hardware interrupts.
20  *
21  * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
22  */
23
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>
33
34 #include <asm/desc.h>
35 #include <asm/ptrace.h>
36 #include <asm/irq.h>
37 #include <asm/idle.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>
43
44 #include <xen/xen.h>
45 #include <xen/hvm.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>
52
53 /*
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.
56  */
57 static DEFINE_MUTEX(irq_mapping_update_lock);
58
59 static LIST_HEAD(xen_irq_list_head);
60
61 /* IRQ <-> VIRQ mapping. */
62 static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1};
63
64 /* IRQ <-> IPI mapping */
65 static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1};
66
67 /* Interrupt types. */
68 enum xen_irq_type {
69         IRQT_UNBOUND = 0,
70         IRQT_PIRQ,
71         IRQT_VIRQ,
72         IRQT_IPI,
73         IRQT_EVTCHN
74 };
75
76 /*
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.
84  *    VIRQ - virq number
85  *    IPI - IPI vector
86  *    EVTCHN -
87  */
88 struct irq_info
89 {
90         struct list_head list;
91         enum xen_irq_type type; /* type */
92         unsigned irq;
93         unsigned short evtchn;  /* event channel */
94         unsigned short cpu;     /* cpu bound */
95
96         union {
97                 unsigned short virq;
98                 enum ipi_vector ipi;
99                 struct {
100                         unsigned short pirq;
101                         unsigned short gsi;
102                         unsigned char vector;
103                         unsigned char flags;
104                         uint16_t domid;
105                 } pirq;
106         } u;
107 };
108 #define PIRQ_NEEDS_EOI  (1 << 0)
109 #define PIRQ_SHAREABLE  (1 << 1)
110
111 static int *evtchn_to_irq;
112
113 static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
114                       cpu_evtchn_mask);
115
116 /* Xen will never allocate port zero for any purpose. */
117 #define VALID_EVTCHN(chn)       ((chn) != 0)
118
119 static struct irq_chip xen_dynamic_chip;
120 static struct irq_chip xen_percpu_chip;
121 static struct irq_chip xen_pirq_chip;
122 static void enable_dynirq(struct irq_data *data);
123 static void disable_dynirq(struct irq_data *data);
124
125 /* Get info for IRQ */
126 static struct irq_info *info_for_irq(unsigned irq)
127 {
128         return irq_get_handler_data(irq);
129 }
130
131 /* Constructors for packed IRQ information. */
132 static void xen_irq_info_common_init(struct irq_info *info,
133                                      unsigned irq,
134                                      enum xen_irq_type type,
135                                      unsigned short evtchn,
136                                      unsigned short cpu)
137 {
138
139         BUG_ON(info->type != IRQT_UNBOUND && info->type != type);
140
141         info->type = type;
142         info->irq = irq;
143         info->evtchn = evtchn;
144         info->cpu = cpu;
145
146         evtchn_to_irq[evtchn] = irq;
147 }
148
149 static void xen_irq_info_evtchn_init(unsigned irq,
150                                      unsigned short evtchn)
151 {
152         struct irq_info *info = info_for_irq(irq);
153
154         xen_irq_info_common_init(info, irq, IRQT_EVTCHN, evtchn, 0);
155 }
156
157 static void xen_irq_info_ipi_init(unsigned cpu,
158                                   unsigned irq,
159                                   unsigned short evtchn,
160                                   enum ipi_vector ipi)
161 {
162         struct irq_info *info = info_for_irq(irq);
163
164         xen_irq_info_common_init(info, irq, IRQT_IPI, evtchn, 0);
165
166         info->u.ipi = ipi;
167
168         per_cpu(ipi_to_irq, cpu)[ipi] = irq;
169 }
170
171 static void xen_irq_info_virq_init(unsigned cpu,
172                                    unsigned irq,
173                                    unsigned short evtchn,
174                                    unsigned short virq)
175 {
176         struct irq_info *info = info_for_irq(irq);
177
178         xen_irq_info_common_init(info, irq, IRQT_VIRQ, evtchn, 0);
179
180         info->u.virq = virq;
181
182         per_cpu(virq_to_irq, cpu)[virq] = irq;
183 }
184
185 static void xen_irq_info_pirq_init(unsigned irq,
186                                    unsigned short evtchn,
187                                    unsigned short pirq,
188                                    unsigned short gsi,
189                                    unsigned short vector,
190                                    uint16_t domid,
191                                    unsigned char flags)
192 {
193         struct irq_info *info = info_for_irq(irq);
194
195         xen_irq_info_common_init(info, irq, IRQT_PIRQ, evtchn, 0);
196
197         info->u.pirq.pirq = pirq;
198         info->u.pirq.gsi = gsi;
199         info->u.pirq.vector = vector;
200         info->u.pirq.domid = domid;
201         info->u.pirq.flags = flags;
202 }
203
204 /*
205  * Accessors for packed IRQ information.
206  */
207 static unsigned int evtchn_from_irq(unsigned irq)
208 {
209         if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq)))
210                 return 0;
211
212         return info_for_irq(irq)->evtchn;
213 }
214
215 unsigned irq_from_evtchn(unsigned int evtchn)
216 {
217         return evtchn_to_irq[evtchn];
218 }
219 EXPORT_SYMBOL_GPL(irq_from_evtchn);
220
221 static enum ipi_vector ipi_from_irq(unsigned irq)
222 {
223         struct irq_info *info = info_for_irq(irq);
224
225         BUG_ON(info == NULL);
226         BUG_ON(info->type != IRQT_IPI);
227
228         return info->u.ipi;
229 }
230
231 static unsigned virq_from_irq(unsigned irq)
232 {
233         struct irq_info *info = info_for_irq(irq);
234
235         BUG_ON(info == NULL);
236         BUG_ON(info->type != IRQT_VIRQ);
237
238         return info->u.virq;
239 }
240
241 static unsigned pirq_from_irq(unsigned irq)
242 {
243         struct irq_info *info = info_for_irq(irq);
244
245         BUG_ON(info == NULL);
246         BUG_ON(info->type != IRQT_PIRQ);
247
248         return info->u.pirq.pirq;
249 }
250
251 static enum xen_irq_type type_from_irq(unsigned irq)
252 {
253         return info_for_irq(irq)->type;
254 }
255
256 static unsigned cpu_from_irq(unsigned irq)
257 {
258         return info_for_irq(irq)->cpu;
259 }
260
261 static unsigned int cpu_from_evtchn(unsigned int evtchn)
262 {
263         int irq = evtchn_to_irq[evtchn];
264         unsigned ret = 0;
265
266         if (irq != -1)
267                 ret = cpu_from_irq(irq);
268
269         return ret;
270 }
271
272 static bool pirq_needs_eoi(unsigned irq)
273 {
274         struct irq_info *info = info_for_irq(irq);
275
276         BUG_ON(info->type != IRQT_PIRQ);
277
278         return info->u.pirq.flags & PIRQ_NEEDS_EOI;
279 }
280
281 static inline unsigned long active_evtchns(unsigned int cpu,
282                                            struct shared_info *sh,
283                                            unsigned int idx)
284 {
285         return (sh->evtchn_pending[idx] &
286                 per_cpu(cpu_evtchn_mask, cpu)[idx] &
287                 ~sh->evtchn_mask[idx]);
288 }
289
290 static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
291 {
292         int irq = evtchn_to_irq[chn];
293
294         BUG_ON(irq == -1);
295 #ifdef CONFIG_SMP
296         cpumask_copy(irq_to_desc(irq)->irq_data.affinity, cpumask_of(cpu));
297 #endif
298
299         clear_bit(chn, per_cpu(cpu_evtchn_mask, cpu_from_irq(irq)));
300         set_bit(chn, per_cpu(cpu_evtchn_mask, cpu));
301
302         info_for_irq(irq)->cpu = cpu;
303 }
304
305 static void init_evtchn_cpu_bindings(void)
306 {
307         int i;
308 #ifdef CONFIG_SMP
309         struct irq_info *info;
310
311         /* By default all event channels notify CPU#0. */
312         list_for_each_entry(info, &xen_irq_list_head, list) {
313                 struct irq_desc *desc = irq_to_desc(info->irq);
314                 cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
315         }
316 #endif
317
318         for_each_possible_cpu(i)
319                 memset(per_cpu(cpu_evtchn_mask, i),
320                        (i == 0) ? ~0 : 0, sizeof(*per_cpu(cpu_evtchn_mask, i)));
321 }
322
323 static inline void clear_evtchn(int port)
324 {
325         struct shared_info *s = HYPERVISOR_shared_info;
326         sync_clear_bit(port, &s->evtchn_pending[0]);
327 }
328
329 static inline void set_evtchn(int port)
330 {
331         struct shared_info *s = HYPERVISOR_shared_info;
332         sync_set_bit(port, &s->evtchn_pending[0]);
333 }
334
335 static inline int test_evtchn(int port)
336 {
337         struct shared_info *s = HYPERVISOR_shared_info;
338         return sync_test_bit(port, &s->evtchn_pending[0]);
339 }
340
341
342 /**
343  * notify_remote_via_irq - send event to remote end of event channel via irq
344  * @irq: irq of event channel to send event to
345  *
346  * Unlike notify_remote_via_evtchn(), this is safe to use across
347  * save/restore. Notifications on a broken connection are silently
348  * dropped.
349  */
350 void notify_remote_via_irq(int irq)
351 {
352         int evtchn = evtchn_from_irq(irq);
353
354         if (VALID_EVTCHN(evtchn))
355                 notify_remote_via_evtchn(evtchn);
356 }
357 EXPORT_SYMBOL_GPL(notify_remote_via_irq);
358
359 static void mask_evtchn(int port)
360 {
361         struct shared_info *s = HYPERVISOR_shared_info;
362         sync_set_bit(port, &s->evtchn_mask[0]);
363 }
364
365 static void unmask_evtchn(int port)
366 {
367         struct shared_info *s = HYPERVISOR_shared_info;
368         unsigned int cpu = get_cpu();
369
370         BUG_ON(!irqs_disabled());
371
372         /* Slow path (hypercall) if this is a non-local port. */
373         if (unlikely(cpu != cpu_from_evtchn(port))) {
374                 struct evtchn_unmask unmask = { .port = port };
375                 (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask);
376         } else {
377                 struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
378
379                 sync_clear_bit(port, &s->evtchn_mask[0]);
380
381                 /*
382                  * The following is basically the equivalent of
383                  * 'hw_resend_irq'. Just like a real IO-APIC we 'lose
384                  * the interrupt edge' if the channel is masked.
385                  */
386                 if (sync_test_bit(port, &s->evtchn_pending[0]) &&
387                     !sync_test_and_set_bit(port / BITS_PER_LONG,
388                                            &vcpu_info->evtchn_pending_sel))
389                         vcpu_info->evtchn_upcall_pending = 1;
390         }
391
392         put_cpu();
393 }
394
395 static void xen_irq_init(unsigned irq)
396 {
397         struct irq_info *info;
398 #ifdef CONFIG_SMP
399         struct irq_desc *desc = irq_to_desc(irq);
400
401         /* By default all event channels notify CPU#0. */
402         cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
403 #endif
404
405         info = kzalloc(sizeof(*info), GFP_KERNEL);
406         if (info == NULL)
407                 panic("Unable to allocate metadata for IRQ%d\n", irq);
408
409         info->type = IRQT_UNBOUND;
410
411         irq_set_handler_data(irq, info);
412
413         list_add_tail(&info->list, &xen_irq_list_head);
414 }
415
416 static int __must_check xen_allocate_irq_dynamic(void)
417 {
418         int first = 0;
419         int irq;
420
421 #ifdef CONFIG_X86_IO_APIC
422         /*
423          * For an HVM guest or domain 0 which see "real" (emulated or
424          * actual respectively) GSIs we allocate dynamic IRQs
425          * e.g. those corresponding to event channels or MSIs
426          * etc. from the range above those "real" GSIs to avoid
427          * collisions.
428          */
429         if (xen_initial_domain() || xen_hvm_domain())
430                 first = get_nr_irqs_gsi();
431 #endif
432
433         irq = irq_alloc_desc_from(first, -1);
434
435         xen_irq_init(irq);
436
437         return irq;
438 }
439
440 static int __must_check xen_allocate_irq_gsi(unsigned gsi)
441 {
442         int irq;
443
444         /*
445          * A PV guest has no concept of a GSI (since it has no ACPI
446          * nor access to/knowledge of the physical APICs). Therefore
447          * all IRQs are dynamically allocated from the entire IRQ
448          * space.
449          */
450         if (xen_pv_domain() && !xen_initial_domain())
451                 return xen_allocate_irq_dynamic();
452
453         /* Legacy IRQ descriptors are already allocated by the arch. */
454         if (gsi < NR_IRQS_LEGACY)
455                 irq = gsi;
456         else
457                 irq = irq_alloc_desc_at(gsi, -1);
458
459         xen_irq_init(irq);
460
461         return irq;
462 }
463
464 static void xen_free_irq(unsigned irq)
465 {
466         struct irq_info *info = irq_get_handler_data(irq);
467
468         list_del(&info->list);
469
470         irq_set_handler_data(irq, NULL);
471
472         kfree(info);
473
474         /* Legacy IRQ descriptors are managed by the arch. */
475         if (irq < NR_IRQS_LEGACY)
476                 return;
477
478         irq_free_desc(irq);
479 }
480
481 static void pirq_query_unmask(int irq)
482 {
483         struct physdev_irq_status_query irq_status;
484         struct irq_info *info = info_for_irq(irq);
485
486         BUG_ON(info->type != IRQT_PIRQ);
487
488         irq_status.irq = pirq_from_irq(irq);
489         if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
490                 irq_status.flags = 0;
491
492         info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
493         if (irq_status.flags & XENIRQSTAT_needs_eoi)
494                 info->u.pirq.flags |= PIRQ_NEEDS_EOI;
495 }
496
497 static bool probing_irq(int irq)
498 {
499         struct irq_desc *desc = irq_to_desc(irq);
500
501         return desc && desc->action == NULL;
502 }
503
504 static void eoi_pirq(struct irq_data *data)
505 {
506         int evtchn = evtchn_from_irq(data->irq);
507         struct physdev_eoi eoi = { .irq = pirq_from_irq(data->irq) };
508         int rc = 0;
509
510         irq_move_irq(data);
511
512         if (VALID_EVTCHN(evtchn))
513                 clear_evtchn(evtchn);
514
515         if (pirq_needs_eoi(data->irq)) {
516                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
517                 WARN_ON(rc);
518         }
519 }
520
521 static void mask_ack_pirq(struct irq_data *data)
522 {
523         disable_dynirq(data);
524         eoi_pirq(data);
525 }
526
527 static unsigned int __startup_pirq(unsigned int irq)
528 {
529         struct evtchn_bind_pirq bind_pirq;
530         struct irq_info *info = info_for_irq(irq);
531         int evtchn = evtchn_from_irq(irq);
532         int rc;
533
534         BUG_ON(info->type != IRQT_PIRQ);
535
536         if (VALID_EVTCHN(evtchn))
537                 goto out;
538
539         bind_pirq.pirq = pirq_from_irq(irq);
540         /* NB. We are happy to share unless we are probing. */
541         bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
542                                         BIND_PIRQ__WILL_SHARE : 0;
543         rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
544         if (rc != 0) {
545                 if (!probing_irq(irq))
546                         printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
547                                irq);
548                 return 0;
549         }
550         evtchn = bind_pirq.port;
551
552         pirq_query_unmask(irq);
553
554         evtchn_to_irq[evtchn] = irq;
555         bind_evtchn_to_cpu(evtchn, 0);
556         info->evtchn = evtchn;
557
558 out:
559         unmask_evtchn(evtchn);
560         eoi_pirq(irq_get_irq_data(irq));
561
562         return 0;
563 }
564
565 static unsigned int startup_pirq(struct irq_data *data)
566 {
567         return __startup_pirq(data->irq);
568 }
569
570 static void shutdown_pirq(struct irq_data *data)
571 {
572         struct evtchn_close close;
573         unsigned int irq = data->irq;
574         struct irq_info *info = info_for_irq(irq);
575         int evtchn = evtchn_from_irq(irq);
576
577         BUG_ON(info->type != IRQT_PIRQ);
578
579         if (!VALID_EVTCHN(evtchn))
580                 return;
581
582         mask_evtchn(evtchn);
583
584         close.port = evtchn;
585         if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
586                 BUG();
587
588         bind_evtchn_to_cpu(evtchn, 0);
589         evtchn_to_irq[evtchn] = -1;
590         info->evtchn = 0;
591 }
592
593 static void enable_pirq(struct irq_data *data)
594 {
595         startup_pirq(data);
596 }
597
598 static void disable_pirq(struct irq_data *data)
599 {
600         disable_dynirq(data);
601 }
602
603 static int find_irq_by_gsi(unsigned gsi)
604 {
605         struct irq_info *info;
606
607         list_for_each_entry(info, &xen_irq_list_head, list) {
608                 if (info->type != IRQT_PIRQ)
609                         continue;
610
611                 if (info->u.pirq.gsi == gsi)
612                         return info->irq;
613         }
614
615         return -1;
616 }
617
618 /*
619  * Do not make any assumptions regarding the relationship between the
620  * IRQ number returned here and the Xen pirq argument.
621  *
622  * Note: We don't assign an event channel until the irq actually started
623  * up.  Return an existing irq if we've already got one for the gsi.
624  *
625  * Shareable implies level triggered, not shareable implies edge
626  * triggered here.
627  */
628 int xen_bind_pirq_gsi_to_irq(unsigned gsi,
629                              unsigned pirq, int shareable, char *name)
630 {
631         int irq = -1;
632         struct physdev_irq irq_op;
633
634         mutex_lock(&irq_mapping_update_lock);
635
636         irq = find_irq_by_gsi(gsi);
637         if (irq != -1) {
638                 printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n",
639                        irq, gsi);
640                 goto out;       /* XXX need refcount? */
641         }
642
643         irq = xen_allocate_irq_gsi(gsi);
644         if (irq < 0)
645                 goto out;
646
647         irq_op.irq = irq;
648         irq_op.vector = 0;
649
650         /* Only the privileged domain can do this. For non-priv, the pcifront
651          * driver provides a PCI bus that does the call to do exactly
652          * this in the priv domain. */
653         if (xen_initial_domain() &&
654             HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
655                 xen_free_irq(irq);
656                 irq = -ENOSPC;
657                 goto out;
658         }
659
660         xen_irq_info_pirq_init(irq, 0, pirq, gsi, irq_op.vector, DOMID_SELF,
661                                shareable ? PIRQ_SHAREABLE : 0);
662
663         pirq_query_unmask(irq);
664         /* We try to use the handler with the appropriate semantic for the
665          * type of interrupt: if the interrupt is an edge triggered
666          * interrupt we use handle_edge_irq.
667          *
668          * On the other hand if the interrupt is level triggered we use
669          * handle_fasteoi_irq like the native code does for this kind of
670          * interrupts.
671          *
672          * Depending on the Xen version, pirq_needs_eoi might return true
673          * not only for level triggered interrupts but for edge triggered
674          * interrupts too. In any case Xen always honors the eoi mechanism,
675          * not injecting any more pirqs of the same kind if the first one
676          * hasn't received an eoi yet. Therefore using the fasteoi handler
677          * is the right choice either way.
678          */
679         if (shareable)
680                 irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
681                                 handle_fasteoi_irq, name);
682         else
683                 irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
684                                 handle_edge_irq, name);
685
686 out:
687         mutex_unlock(&irq_mapping_update_lock);
688
689         return irq;
690 }
691
692 #ifdef CONFIG_PCI_MSI
693 int xen_allocate_pirq_msi(struct pci_dev *dev, struct msi_desc *msidesc)
694 {
695         int rc;
696         struct physdev_get_free_pirq op_get_free_pirq;
697
698         op_get_free_pirq.type = MAP_PIRQ_TYPE_MSI;
699         rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);
700
701         WARN_ONCE(rc == -ENOSYS,
702                   "hypervisor does not support the PHYSDEVOP_get_free_pirq interface\n");
703
704         return rc ? -1 : op_get_free_pirq.pirq;
705 }
706
707 int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
708                              int pirq, int vector, const char *name,
709                              domid_t domid)
710 {
711         int irq, ret;
712
713         mutex_lock(&irq_mapping_update_lock);
714
715         irq = xen_allocate_irq_dynamic();
716         if (irq == -1)
717                 goto out;
718
719         irq_set_chip_and_handler_name(irq, &xen_pirq_chip, handle_edge_irq,
720                         name);
721
722         xen_irq_info_pirq_init(irq, 0, pirq, 0, vector, domid, 0);
723         ret = irq_set_msi_desc(irq, msidesc);
724         if (ret < 0)
725                 goto error_irq;
726 out:
727         mutex_unlock(&irq_mapping_update_lock);
728         return irq;
729 error_irq:
730         mutex_unlock(&irq_mapping_update_lock);
731         xen_free_irq(irq);
732         return -1;
733 }
734 #endif
735
736 int xen_destroy_irq(int irq)
737 {
738         struct irq_desc *desc;
739         struct physdev_unmap_pirq unmap_irq;
740         struct irq_info *info = info_for_irq(irq);
741         int rc = -ENOENT;
742
743         mutex_lock(&irq_mapping_update_lock);
744
745         desc = irq_to_desc(irq);
746         if (!desc)
747                 goto out;
748
749         if (xen_initial_domain()) {
750                 unmap_irq.pirq = info->u.pirq.pirq;
751                 unmap_irq.domid = info->u.pirq.domid;
752                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
753                 /* If another domain quits without making the pci_disable_msix
754                  * call, the Xen hypervisor takes care of freeing the PIRQs
755                  * (free_domain_pirqs).
756                  */
757                 if ((rc == -ESRCH && info->u.pirq.domid != DOMID_SELF))
758                         printk(KERN_INFO "domain %d does not have %d anymore\n",
759                                 info->u.pirq.domid, info->u.pirq.pirq);
760                 else if (rc) {
761                         printk(KERN_WARNING "unmap irq failed %d\n", rc);
762                         goto out;
763                 }
764         }
765
766         xen_free_irq(irq);
767
768 out:
769         mutex_unlock(&irq_mapping_update_lock);
770         return rc;
771 }
772
773 int xen_irq_from_pirq(unsigned pirq)
774 {
775         int irq;
776
777         struct irq_info *info;
778
779         mutex_lock(&irq_mapping_update_lock);
780
781         list_for_each_entry(info, &xen_irq_list_head, list) {
782                 if (info == NULL || info->type != IRQT_PIRQ)
783                         continue;
784                 irq = info->irq;
785                 if (info->u.pirq.pirq == pirq)
786                         goto out;
787         }
788         irq = -1;
789 out:
790         mutex_unlock(&irq_mapping_update_lock);
791
792         return irq;
793 }
794
795
796 int xen_pirq_from_irq(unsigned irq)
797 {
798         return pirq_from_irq(irq);
799 }
800 EXPORT_SYMBOL_GPL(xen_pirq_from_irq);
801 int bind_evtchn_to_irq(unsigned int evtchn)
802 {
803         int irq;
804
805         mutex_lock(&irq_mapping_update_lock);
806
807         irq = evtchn_to_irq[evtchn];
808
809         if (irq == -1) {
810                 irq = xen_allocate_irq_dynamic();
811                 if (irq == -1)
812                         goto out;
813
814                 irq_set_chip_and_handler_name(irq, &xen_dynamic_chip,
815                                               handle_edge_irq, "event");
816
817                 xen_irq_info_evtchn_init(irq, evtchn);
818         }
819
820 out:
821         mutex_unlock(&irq_mapping_update_lock);
822
823         return irq;
824 }
825 EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
826
827 static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
828 {
829         struct evtchn_bind_ipi bind_ipi;
830         int evtchn, irq;
831
832         mutex_lock(&irq_mapping_update_lock);
833
834         irq = per_cpu(ipi_to_irq, cpu)[ipi];
835
836         if (irq == -1) {
837                 irq = xen_allocate_irq_dynamic();
838                 if (irq < 0)
839                         goto out;
840
841                 irq_set_chip_and_handler_name(irq, &xen_percpu_chip,
842                                               handle_percpu_irq, "ipi");
843
844                 bind_ipi.vcpu = cpu;
845                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
846                                                 &bind_ipi) != 0)
847                         BUG();
848                 evtchn = bind_ipi.port;
849
850                 xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
851
852                 bind_evtchn_to_cpu(evtchn, cpu);
853         }
854
855  out:
856         mutex_unlock(&irq_mapping_update_lock);
857         return irq;
858 }
859
860 static int bind_interdomain_evtchn_to_irq(unsigned int remote_domain,
861                                           unsigned int remote_port)
862 {
863         struct evtchn_bind_interdomain bind_interdomain;
864         int err;
865
866         bind_interdomain.remote_dom  = remote_domain;
867         bind_interdomain.remote_port = remote_port;
868
869         err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain,
870                                           &bind_interdomain);
871
872         return err ? : bind_evtchn_to_irq(bind_interdomain.local_port);
873 }
874
875
876 int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
877 {
878         struct evtchn_bind_virq bind_virq;
879         int evtchn, irq;
880
881         mutex_lock(&irq_mapping_update_lock);
882
883         irq = per_cpu(virq_to_irq, cpu)[virq];
884
885         if (irq == -1) {
886                 irq = xen_allocate_irq_dynamic();
887                 if (irq == -1)
888                         goto out;
889
890                 irq_set_chip_and_handler_name(irq, &xen_percpu_chip,
891                                               handle_percpu_irq, "virq");
892
893                 bind_virq.virq = virq;
894                 bind_virq.vcpu = cpu;
895                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
896                                                 &bind_virq) != 0)
897                         BUG();
898                 evtchn = bind_virq.port;
899
900                 xen_irq_info_virq_init(cpu, irq, evtchn, virq);
901
902                 bind_evtchn_to_cpu(evtchn, cpu);
903         }
904
905 out:
906         mutex_unlock(&irq_mapping_update_lock);
907
908         return irq;
909 }
910
911 static void unbind_from_irq(unsigned int irq)
912 {
913         struct evtchn_close close;
914         int evtchn = evtchn_from_irq(irq);
915
916         mutex_lock(&irq_mapping_update_lock);
917
918         if (VALID_EVTCHN(evtchn)) {
919                 close.port = evtchn;
920                 if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
921                         BUG();
922
923                 switch (type_from_irq(irq)) {
924                 case IRQT_VIRQ:
925                         per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
926                                 [virq_from_irq(irq)] = -1;
927                         break;
928                 case IRQT_IPI:
929                         per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
930                                 [ipi_from_irq(irq)] = -1;
931                         break;
932                 default:
933                         break;
934                 }
935
936                 /* Closed ports are implicitly re-bound to VCPU0. */
937                 bind_evtchn_to_cpu(evtchn, 0);
938
939                 evtchn_to_irq[evtchn] = -1;
940         }
941
942         BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);
943
944         xen_free_irq(irq);
945
946         mutex_unlock(&irq_mapping_update_lock);
947 }
948
949 int bind_evtchn_to_irqhandler(unsigned int evtchn,
950                               irq_handler_t handler,
951                               unsigned long irqflags,
952                               const char *devname, void *dev_id)
953 {
954         int irq, retval;
955
956         irq = bind_evtchn_to_irq(evtchn);
957         if (irq < 0)
958                 return irq;
959         retval = request_irq(irq, handler, irqflags, devname, dev_id);
960         if (retval != 0) {
961                 unbind_from_irq(irq);
962                 return retval;
963         }
964
965         return irq;
966 }
967 EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler);
968
969 int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain,
970                                           unsigned int remote_port,
971                                           irq_handler_t handler,
972                                           unsigned long irqflags,
973                                           const char *devname,
974                                           void *dev_id)
975 {
976         int irq, retval;
977
978         irq = bind_interdomain_evtchn_to_irq(remote_domain, remote_port);
979         if (irq < 0)
980                 return irq;
981
982         retval = request_irq(irq, handler, irqflags, devname, dev_id);
983         if (retval != 0) {
984                 unbind_from_irq(irq);
985                 return retval;
986         }
987
988         return irq;
989 }
990 EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irqhandler);
991
992 int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
993                             irq_handler_t handler,
994                             unsigned long irqflags, const char *devname, void *dev_id)
995 {
996         int irq, retval;
997
998         irq = bind_virq_to_irq(virq, cpu);
999         if (irq < 0)
1000                 return irq;
1001         retval = request_irq(irq, handler, irqflags, devname, dev_id);
1002         if (retval != 0) {
1003                 unbind_from_irq(irq);
1004                 return retval;
1005         }
1006
1007         return irq;
1008 }
1009 EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);
1010
1011 int bind_ipi_to_irqhandler(enum ipi_vector ipi,
1012                            unsigned int cpu,
1013                            irq_handler_t handler,
1014                            unsigned long irqflags,
1015                            const char *devname,
1016                            void *dev_id)
1017 {
1018         int irq, retval;
1019
1020         irq = bind_ipi_to_irq(ipi, cpu);
1021         if (irq < 0)
1022                 return irq;
1023
1024         irqflags |= IRQF_NO_SUSPEND | IRQF_FORCE_RESUME | IRQF_EARLY_RESUME;
1025         retval = request_irq(irq, handler, irqflags, devname, dev_id);
1026         if (retval != 0) {
1027                 unbind_from_irq(irq);
1028                 return retval;
1029         }
1030
1031         return irq;
1032 }
1033
1034 void unbind_from_irqhandler(unsigned int irq, void *dev_id)
1035 {
1036         free_irq(irq, dev_id);
1037         unbind_from_irq(irq);
1038 }
1039 EXPORT_SYMBOL_GPL(unbind_from_irqhandler);
1040
1041 void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
1042 {
1043         int irq = per_cpu(ipi_to_irq, cpu)[vector];
1044         BUG_ON(irq < 0);
1045         notify_remote_via_irq(irq);
1046 }
1047
1048 irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
1049 {
1050         struct shared_info *sh = HYPERVISOR_shared_info;
1051         int cpu = smp_processor_id();
1052         unsigned long *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu);
1053         int i;
1054         unsigned long flags;
1055         static DEFINE_SPINLOCK(debug_lock);
1056         struct vcpu_info *v;
1057
1058         spin_lock_irqsave(&debug_lock, flags);
1059
1060         printk("\nvcpu %d\n  ", cpu);
1061
1062         for_each_online_cpu(i) {
1063                 int pending;
1064                 v = per_cpu(xen_vcpu, i);
1065                 pending = (get_irq_regs() && i == cpu)
1066                         ? xen_irqs_disabled(get_irq_regs())
1067                         : v->evtchn_upcall_mask;
1068                 printk("%d: masked=%d pending=%d event_sel %0*lx\n  ", i,
1069                        pending, v->evtchn_upcall_pending,
1070                        (int)(sizeof(v->evtchn_pending_sel)*2),
1071                        v->evtchn_pending_sel);
1072         }
1073         v = per_cpu(xen_vcpu, cpu);
1074
1075         printk("\npending:\n   ");
1076         for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--)
1077                 printk("%0*lx%s", (int)sizeof(sh->evtchn_pending[0])*2,
1078                        sh->evtchn_pending[i],
1079                        i % 8 == 0 ? "\n   " : " ");
1080         printk("\nglobal mask:\n   ");
1081         for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
1082                 printk("%0*lx%s",
1083                        (int)(sizeof(sh->evtchn_mask[0])*2),
1084                        sh->evtchn_mask[i],
1085                        i % 8 == 0 ? "\n   " : " ");
1086
1087         printk("\nglobally unmasked:\n   ");
1088         for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
1089                 printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
1090                        sh->evtchn_pending[i] & ~sh->evtchn_mask[i],
1091                        i % 8 == 0 ? "\n   " : " ");
1092
1093         printk("\nlocal cpu%d mask:\n   ", cpu);
1094         for (i = (NR_EVENT_CHANNELS/BITS_PER_LONG)-1; i >= 0; i--)
1095                 printk("%0*lx%s", (int)(sizeof(cpu_evtchn[0])*2),
1096                        cpu_evtchn[i],
1097                        i % 8 == 0 ? "\n   " : " ");
1098
1099         printk("\nlocally unmasked:\n   ");
1100         for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) {
1101                 unsigned long pending = sh->evtchn_pending[i]
1102                         & ~sh->evtchn_mask[i]
1103                         & cpu_evtchn[i];
1104                 printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
1105                        pending, i % 8 == 0 ? "\n   " : " ");
1106         }
1107
1108         printk("\npending list:\n");
1109         for (i = 0; i < NR_EVENT_CHANNELS; i++) {
1110                 if (sync_test_bit(i, sh->evtchn_pending)) {
1111                         int word_idx = i / BITS_PER_LONG;
1112                         printk("  %d: event %d -> irq %d%s%s%s\n",
1113                                cpu_from_evtchn(i), i,
1114                                evtchn_to_irq[i],
1115                                sync_test_bit(word_idx, &v->evtchn_pending_sel)
1116                                              ? "" : " l2-clear",
1117                                !sync_test_bit(i, sh->evtchn_mask)
1118                                              ? "" : " globally-masked",
1119                                sync_test_bit(i, cpu_evtchn)
1120                                              ? "" : " locally-masked");
1121                 }
1122         }
1123
1124         spin_unlock_irqrestore(&debug_lock, flags);
1125
1126         return IRQ_HANDLED;
1127 }
1128
1129 static DEFINE_PER_CPU(unsigned, xed_nesting_count);
1130 static DEFINE_PER_CPU(unsigned int, current_word_idx);
1131 static DEFINE_PER_CPU(unsigned int, current_bit_idx);
1132
1133 /*
1134  * Mask out the i least significant bits of w
1135  */
1136 #define MASK_LSBS(w, i) (w & ((~0UL) << i))
1137
1138 /*
1139  * Search the CPUs pending events bitmasks.  For each one found, map
1140  * the event number to an irq, and feed it into do_IRQ() for
1141  * handling.
1142  *
1143  * Xen uses a two-level bitmap to speed searching.  The first level is
1144  * a bitset of words which contain pending event bits.  The second
1145  * level is a bitset of pending events themselves.
1146  */
1147 static void __xen_evtchn_do_upcall(void)
1148 {
1149         int start_word_idx, start_bit_idx;
1150         int word_idx, bit_idx;
1151         int i;
1152         int cpu = get_cpu();
1153         struct shared_info *s = HYPERVISOR_shared_info;
1154         struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
1155         unsigned count;
1156
1157         do {
1158                 unsigned long pending_words;
1159
1160                 vcpu_info->evtchn_upcall_pending = 0;
1161
1162                 if (__this_cpu_inc_return(xed_nesting_count) - 1)
1163                         goto out;
1164
1165 #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
1166                 /* Clear master flag /before/ clearing selector flag. */
1167                 wmb();
1168 #endif
1169                 pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
1170
1171                 start_word_idx = __this_cpu_read(current_word_idx);
1172                 start_bit_idx = __this_cpu_read(current_bit_idx);
1173
1174                 word_idx = start_word_idx;
1175
1176                 for (i = 0; pending_words != 0; i++) {
1177                         unsigned long pending_bits;
1178                         unsigned long words;
1179
1180                         words = MASK_LSBS(pending_words, word_idx);
1181
1182                         /*
1183                          * If we masked out all events, wrap to beginning.
1184                          */
1185                         if (words == 0) {
1186                                 word_idx = 0;
1187                                 bit_idx = 0;
1188                                 continue;
1189                         }
1190                         word_idx = __ffs(words);
1191
1192                         pending_bits = active_evtchns(cpu, s, word_idx);
1193                         bit_idx = 0; /* usually scan entire word from start */
1194                         if (word_idx == start_word_idx) {
1195                                 /* We scan the starting word in two parts */
1196                                 if (i == 0)
1197                                         /* 1st time: start in the middle */
1198                                         bit_idx = start_bit_idx;
1199                                 else
1200                                         /* 2nd time: mask bits done already */
1201                                         bit_idx &= (1UL << start_bit_idx) - 1;
1202                         }
1203
1204                         do {
1205                                 unsigned long bits;
1206                                 int port, irq;
1207                                 struct irq_desc *desc;
1208
1209                                 bits = MASK_LSBS(pending_bits, bit_idx);
1210
1211                                 /* If we masked out all events, move on. */
1212                                 if (bits == 0)
1213                                         break;
1214
1215                                 bit_idx = __ffs(bits);
1216
1217                                 /* Process port. */
1218                                 port = (word_idx * BITS_PER_LONG) + bit_idx;
1219                                 irq = evtchn_to_irq[port];
1220
1221                                 if (irq != -1) {
1222                                         desc = irq_to_desc(irq);
1223                                         if (desc)
1224                                                 generic_handle_irq_desc(irq, desc);
1225                                 }
1226
1227                                 bit_idx = (bit_idx + 1) % BITS_PER_LONG;
1228
1229                                 /* Next caller starts at last processed + 1 */
1230                                 __this_cpu_write(current_word_idx,
1231                                                  bit_idx ? word_idx :
1232                                                  (word_idx+1) % BITS_PER_LONG);
1233                                 __this_cpu_write(current_bit_idx, bit_idx);
1234                         } while (bit_idx != 0);
1235
1236                         /* Scan start_l1i twice; all others once. */
1237                         if ((word_idx != start_word_idx) || (i != 0))
1238                                 pending_words &= ~(1UL << word_idx);
1239
1240                         word_idx = (word_idx + 1) % BITS_PER_LONG;
1241                 }
1242
1243                 BUG_ON(!irqs_disabled());
1244
1245                 count = __this_cpu_read(xed_nesting_count);
1246                 __this_cpu_write(xed_nesting_count, 0);
1247         } while (count != 1 || vcpu_info->evtchn_upcall_pending);
1248
1249 out:
1250
1251         put_cpu();
1252 }
1253
1254 void xen_evtchn_do_upcall(struct pt_regs *regs)
1255 {
1256         struct pt_regs *old_regs = set_irq_regs(regs);
1257
1258         exit_idle();
1259         irq_enter();
1260
1261         __xen_evtchn_do_upcall();
1262
1263         irq_exit();
1264         set_irq_regs(old_regs);
1265 }
1266
1267 void xen_hvm_evtchn_do_upcall(void)
1268 {
1269         __xen_evtchn_do_upcall();
1270 }
1271 EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall);
1272
1273 /* Rebind a new event channel to an existing irq. */
1274 void rebind_evtchn_irq(int evtchn, int irq)
1275 {
1276         struct irq_info *info = info_for_irq(irq);
1277
1278         /* Make sure the irq is masked, since the new event channel
1279            will also be masked. */
1280         disable_irq(irq);
1281
1282         mutex_lock(&irq_mapping_update_lock);
1283
1284         /* After resume the irq<->evtchn mappings are all cleared out */
1285         BUG_ON(evtchn_to_irq[evtchn] != -1);
1286         /* Expect irq to have been bound before,
1287            so there should be a proper type */
1288         BUG_ON(info->type == IRQT_UNBOUND);
1289
1290         xen_irq_info_evtchn_init(irq, evtchn);
1291
1292         mutex_unlock(&irq_mapping_update_lock);
1293
1294         /* new event channels are always bound to cpu 0 */
1295         irq_set_affinity(irq, cpumask_of(0));
1296
1297         /* Unmask the event channel. */
1298         enable_irq(irq);
1299 }
1300
1301 /* Rebind an evtchn so that it gets delivered to a specific cpu */
1302 static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
1303 {
1304         struct evtchn_bind_vcpu bind_vcpu;
1305         int evtchn = evtchn_from_irq(irq);
1306
1307         if (!VALID_EVTCHN(evtchn))
1308                 return -1;
1309
1310         /*
1311          * Events delivered via platform PCI interrupts are always
1312          * routed to vcpu 0 and hence cannot be rebound.
1313          */
1314         if (xen_hvm_domain() && !xen_have_vector_callback)
1315                 return -1;
1316
1317         /* Send future instances of this interrupt to other vcpu. */
1318         bind_vcpu.port = evtchn;
1319         bind_vcpu.vcpu = tcpu;
1320
1321         /*
1322          * If this fails, it usually just indicates that we're dealing with a
1323          * virq or IPI channel, which don't actually need to be rebound. Ignore
1324          * it, but don't do the xenlinux-level rebind in that case.
1325          */
1326         if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
1327                 bind_evtchn_to_cpu(evtchn, tcpu);
1328
1329         return 0;
1330 }
1331
1332 static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest,
1333                             bool force)
1334 {
1335         unsigned tcpu = cpumask_first(dest);
1336
1337         return rebind_irq_to_cpu(data->irq, tcpu);
1338 }
1339
1340 int resend_irq_on_evtchn(unsigned int irq)
1341 {
1342         int masked, evtchn = evtchn_from_irq(irq);
1343         struct shared_info *s = HYPERVISOR_shared_info;
1344
1345         if (!VALID_EVTCHN(evtchn))
1346                 return 1;
1347
1348         masked = sync_test_and_set_bit(evtchn, s->evtchn_mask);
1349         sync_set_bit(evtchn, s->evtchn_pending);
1350         if (!masked)
1351                 unmask_evtchn(evtchn);
1352
1353         return 1;
1354 }
1355
1356 static void enable_dynirq(struct irq_data *data)
1357 {
1358         int evtchn = evtchn_from_irq(data->irq);
1359
1360         if (VALID_EVTCHN(evtchn))
1361                 unmask_evtchn(evtchn);
1362 }
1363
1364 static void disable_dynirq(struct irq_data *data)
1365 {
1366         int evtchn = evtchn_from_irq(data->irq);
1367
1368         if (VALID_EVTCHN(evtchn))
1369                 mask_evtchn(evtchn);
1370 }
1371
1372 static void ack_dynirq(struct irq_data *data)
1373 {
1374         int evtchn = evtchn_from_irq(data->irq);
1375
1376         irq_move_irq(data);
1377
1378         if (VALID_EVTCHN(evtchn))
1379                 clear_evtchn(evtchn);
1380 }
1381
1382 static void mask_ack_dynirq(struct irq_data *data)
1383 {
1384         disable_dynirq(data);
1385         ack_dynirq(data);
1386 }
1387
1388 static int retrigger_dynirq(struct irq_data *data)
1389 {
1390         int evtchn = evtchn_from_irq(data->irq);
1391         struct shared_info *sh = HYPERVISOR_shared_info;
1392         int ret = 0;
1393
1394         if (VALID_EVTCHN(evtchn)) {
1395                 int masked;
1396
1397                 masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask);
1398                 sync_set_bit(evtchn, sh->evtchn_pending);
1399                 if (!masked)
1400                         unmask_evtchn(evtchn);
1401                 ret = 1;
1402         }
1403
1404         return ret;
1405 }
1406
1407 static void restore_pirqs(void)
1408 {
1409         int pirq, rc, irq, gsi;
1410         struct physdev_map_pirq map_irq;
1411         struct irq_info *info;
1412
1413         list_for_each_entry(info, &xen_irq_list_head, list) {
1414                 if (info->type != IRQT_PIRQ)
1415                         continue;
1416
1417                 pirq = info->u.pirq.pirq;
1418                 gsi = info->u.pirq.gsi;
1419                 irq = info->irq;
1420
1421                 /* save/restore of PT devices doesn't work, so at this point the
1422                  * only devices present are GSI based emulated devices */
1423                 if (!gsi)
1424                         continue;
1425
1426                 map_irq.domid = DOMID_SELF;
1427                 map_irq.type = MAP_PIRQ_TYPE_GSI;
1428                 map_irq.index = gsi;
1429                 map_irq.pirq = pirq;
1430
1431                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
1432                 if (rc) {
1433                         printk(KERN_WARNING "xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
1434                                         gsi, irq, pirq, rc);
1435                         xen_free_irq(irq);
1436                         continue;
1437                 }
1438
1439                 printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
1440
1441                 __startup_pirq(irq);
1442         }
1443 }
1444
1445 static void restore_cpu_virqs(unsigned int cpu)
1446 {
1447         struct evtchn_bind_virq bind_virq;
1448         int virq, irq, evtchn;
1449
1450         for (virq = 0; virq < NR_VIRQS; virq++) {
1451                 if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1)
1452                         continue;
1453
1454                 BUG_ON(virq_from_irq(irq) != virq);
1455
1456                 /* Get a new binding from Xen. */
1457                 bind_virq.virq = virq;
1458                 bind_virq.vcpu = cpu;
1459                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
1460                                                 &bind_virq) != 0)
1461                         BUG();
1462                 evtchn = bind_virq.port;
1463
1464                 /* Record the new mapping. */
1465                 xen_irq_info_virq_init(cpu, irq, evtchn, virq);
1466                 bind_evtchn_to_cpu(evtchn, cpu);
1467         }
1468 }
1469
1470 static void restore_cpu_ipis(unsigned int cpu)
1471 {
1472         struct evtchn_bind_ipi bind_ipi;
1473         int ipi, irq, evtchn;
1474
1475         for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) {
1476                 if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1)
1477                         continue;
1478
1479                 BUG_ON(ipi_from_irq(irq) != ipi);
1480
1481                 /* Get a new binding from Xen. */
1482                 bind_ipi.vcpu = cpu;
1483                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
1484                                                 &bind_ipi) != 0)
1485                         BUG();
1486                 evtchn = bind_ipi.port;
1487
1488                 /* Record the new mapping. */
1489                 xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
1490                 bind_evtchn_to_cpu(evtchn, cpu);
1491         }
1492 }
1493
1494 /* Clear an irq's pending state, in preparation for polling on it */
1495 void xen_clear_irq_pending(int irq)
1496 {
1497         int evtchn = evtchn_from_irq(irq);
1498
1499         if (VALID_EVTCHN(evtchn))
1500                 clear_evtchn(evtchn);
1501 }
1502 EXPORT_SYMBOL(xen_clear_irq_pending);
1503 void xen_set_irq_pending(int irq)
1504 {
1505         int evtchn = evtchn_from_irq(irq);
1506
1507         if (VALID_EVTCHN(evtchn))
1508                 set_evtchn(evtchn);
1509 }
1510
1511 bool xen_test_irq_pending(int irq)
1512 {
1513         int evtchn = evtchn_from_irq(irq);
1514         bool ret = false;
1515
1516         if (VALID_EVTCHN(evtchn))
1517                 ret = test_evtchn(evtchn);
1518
1519         return ret;
1520 }
1521
1522 /* Poll waiting for an irq to become pending with timeout.  In the usual case,
1523  * the irq will be disabled so it won't deliver an interrupt. */
1524 void xen_poll_irq_timeout(int irq, u64 timeout)
1525 {
1526         evtchn_port_t evtchn = evtchn_from_irq(irq);
1527
1528         if (VALID_EVTCHN(evtchn)) {
1529                 struct sched_poll poll;
1530
1531                 poll.nr_ports = 1;
1532                 poll.timeout = timeout;
1533                 set_xen_guest_handle(poll.ports, &evtchn);
1534
1535                 if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
1536                         BUG();
1537         }
1538 }
1539 EXPORT_SYMBOL(xen_poll_irq_timeout);
1540 /* Poll waiting for an irq to become pending.  In the usual case, the
1541  * irq will be disabled so it won't deliver an interrupt. */
1542 void xen_poll_irq(int irq)
1543 {
1544         xen_poll_irq_timeout(irq, 0 /* no timeout */);
1545 }
1546
1547 /* Check whether the IRQ line is shared with other guests. */
1548 int xen_test_irq_shared(int irq)
1549 {
1550         struct irq_info *info = info_for_irq(irq);
1551         struct physdev_irq_status_query irq_status = { .irq = info->u.pirq.pirq };
1552
1553         if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
1554                 return 0;
1555         return !(irq_status.flags & XENIRQSTAT_shared);
1556 }
1557 EXPORT_SYMBOL_GPL(xen_test_irq_shared);
1558
1559 void xen_irq_resume(void)
1560 {
1561         unsigned int cpu, evtchn;
1562         struct irq_info *info;
1563
1564         init_evtchn_cpu_bindings();
1565
1566         /* New event-channel space is not 'live' yet. */
1567         for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
1568                 mask_evtchn(evtchn);
1569
1570         /* No IRQ <-> event-channel mappings. */
1571         list_for_each_entry(info, &xen_irq_list_head, list)
1572                 info->evtchn = 0; /* zap event-channel binding */
1573
1574         for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
1575                 evtchn_to_irq[evtchn] = -1;
1576
1577         for_each_possible_cpu(cpu) {
1578                 restore_cpu_virqs(cpu);
1579                 restore_cpu_ipis(cpu);
1580         }
1581
1582         restore_pirqs();
1583 }
1584
1585 static struct irq_chip xen_dynamic_chip __read_mostly = {
1586         .name                   = "xen-dyn",
1587
1588         .irq_disable            = disable_dynirq,
1589         .irq_mask               = disable_dynirq,
1590         .irq_unmask             = enable_dynirq,
1591
1592         .irq_ack                = ack_dynirq,
1593         .irq_mask_ack           = mask_ack_dynirq,
1594
1595         .irq_set_affinity       = set_affinity_irq,
1596         .irq_retrigger          = retrigger_dynirq,
1597 };
1598
1599 static struct irq_chip xen_pirq_chip __read_mostly = {
1600         .name                   = "xen-pirq",
1601
1602         .irq_startup            = startup_pirq,
1603         .irq_shutdown           = shutdown_pirq,
1604         .irq_enable             = enable_pirq,
1605         .irq_disable            = disable_pirq,
1606
1607         .irq_mask               = disable_dynirq,
1608         .irq_unmask             = enable_dynirq,
1609
1610         .irq_ack                = eoi_pirq,
1611         .irq_eoi                = eoi_pirq,
1612         .irq_mask_ack           = mask_ack_pirq,
1613
1614         .irq_set_affinity       = set_affinity_irq,
1615
1616         .irq_retrigger          = retrigger_dynirq,
1617 };
1618
1619 static struct irq_chip xen_percpu_chip __read_mostly = {
1620         .name                   = "xen-percpu",
1621
1622         .irq_disable            = disable_dynirq,
1623         .irq_mask               = disable_dynirq,
1624         .irq_unmask             = enable_dynirq,
1625
1626         .irq_ack                = ack_dynirq,
1627 };
1628
1629 int xen_set_callback_via(uint64_t via)
1630 {
1631         struct xen_hvm_param a;
1632         a.domid = DOMID_SELF;
1633         a.index = HVM_PARAM_CALLBACK_IRQ;
1634         a.value = via;
1635         return HYPERVISOR_hvm_op(HVMOP_set_param, &a);
1636 }
1637 EXPORT_SYMBOL_GPL(xen_set_callback_via);
1638
1639 #ifdef CONFIG_XEN_PVHVM
1640 /* Vector callbacks are better than PCI interrupts to receive event
1641  * channel notifications because we can receive vector callbacks on any
1642  * vcpu and we don't need PCI support or APIC interactions. */
1643 void xen_callback_vector(void)
1644 {
1645         int rc;
1646         uint64_t callback_via;
1647         if (xen_have_vector_callback) {
1648                 callback_via = HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK);
1649                 rc = xen_set_callback_via(callback_via);
1650                 if (rc) {
1651                         printk(KERN_ERR "Request for Xen HVM callback vector"
1652                                         " failed.\n");
1653                         xen_have_vector_callback = 0;
1654                         return;
1655                 }
1656                 printk(KERN_INFO "Xen HVM callback vector for event delivery is "
1657                                 "enabled\n");
1658                 /* in the restore case the vector has already been allocated */
1659                 if (!test_bit(XEN_HVM_EVTCHN_CALLBACK, used_vectors))
1660                         alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK, xen_hvm_callback_vector);
1661         }
1662 }
1663 #else
1664 void xen_callback_vector(void) {}
1665 #endif
1666
1667 void __init xen_init_IRQ(void)
1668 {
1669         int i;
1670
1671         evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
1672                                     GFP_KERNEL);
1673         for (i = 0; i < NR_EVENT_CHANNELS; i++)
1674                 evtchn_to_irq[i] = -1;
1675
1676         init_evtchn_cpu_bindings();
1677
1678         /* No event channels are 'live' right now. */
1679         for (i = 0; i < NR_EVENT_CHANNELS; i++)
1680                 mask_evtchn(i);
1681
1682         if (xen_hvm_domain()) {
1683                 xen_callback_vector();
1684                 native_init_IRQ();
1685                 /* pci_xen_hvm_init must be called after native_init_IRQ so that
1686                  * __acpi_register_gsi can point at the right function */
1687                 pci_xen_hvm_init();
1688         } else {
1689                 irq_ctx_init(smp_processor_id());
1690                 if (xen_initial_domain())
1691                         pci_xen_initial_domain();
1692         }
1693 }