xen/gntdev,gntalloc: Remove unneeded VM flags
[sfrench/cifs-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 recieved, 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_SPINLOCK(irq_mapping_update_lock);
58
59 /* IRQ <-> VIRQ mapping. */
60 static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1};
61
62 /* IRQ <-> IPI mapping */
63 static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1};
64
65 /* Interrupt types. */
66 enum xen_irq_type {
67         IRQT_UNBOUND = 0,
68         IRQT_PIRQ,
69         IRQT_VIRQ,
70         IRQT_IPI,
71         IRQT_EVTCHN
72 };
73
74 /*
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.
82  *    VIRQ - virq number
83  *    IPI - IPI vector
84  *    EVTCHN -
85  */
86 struct irq_info
87 {
88         enum xen_irq_type type; /* type */
89         unsigned short evtchn;  /* event channel */
90         unsigned short cpu;     /* cpu bound */
91
92         union {
93                 unsigned short virq;
94                 enum ipi_vector ipi;
95                 struct {
96                         unsigned short pirq;
97                         unsigned short gsi;
98                         unsigned char vector;
99                         unsigned char flags;
100                 } pirq;
101         } u;
102 };
103 #define PIRQ_NEEDS_EOI  (1 << 0)
104 #define PIRQ_SHAREABLE  (1 << 1)
105
106 static struct irq_info *irq_info;
107 static int *pirq_to_irq;
108
109 static int *evtchn_to_irq;
110 struct cpu_evtchn_s {
111         unsigned long bits[NR_EVENT_CHANNELS/BITS_PER_LONG];
112 };
113
114 static __initdata struct cpu_evtchn_s init_evtchn_mask = {
115         .bits[0 ... (NR_EVENT_CHANNELS/BITS_PER_LONG)-1] = ~0ul,
116 };
117 static struct cpu_evtchn_s *cpu_evtchn_mask_p = &init_evtchn_mask;
118
119 static inline unsigned long *cpu_evtchn_mask(int cpu)
120 {
121         return cpu_evtchn_mask_p[cpu].bits;
122 }
123
124 /* Xen will never allocate port zero for any purpose. */
125 #define VALID_EVTCHN(chn)       ((chn) != 0)
126
127 static struct irq_chip xen_dynamic_chip;
128 static struct irq_chip xen_percpu_chip;
129 static struct irq_chip xen_pirq_chip;
130
131 /* Constructor for packed IRQ information. */
132 static struct irq_info mk_unbound_info(void)
133 {
134         return (struct irq_info) { .type = IRQT_UNBOUND };
135 }
136
137 static struct irq_info mk_evtchn_info(unsigned short evtchn)
138 {
139         return (struct irq_info) { .type = IRQT_EVTCHN, .evtchn = evtchn,
140                         .cpu = 0 };
141 }
142
143 static struct irq_info mk_ipi_info(unsigned short evtchn, enum ipi_vector ipi)
144 {
145         return (struct irq_info) { .type = IRQT_IPI, .evtchn = evtchn,
146                         .cpu = 0, .u.ipi = ipi };
147 }
148
149 static struct irq_info mk_virq_info(unsigned short evtchn, unsigned short virq)
150 {
151         return (struct irq_info) { .type = IRQT_VIRQ, .evtchn = evtchn,
152                         .cpu = 0, .u.virq = virq };
153 }
154
155 static struct irq_info mk_pirq_info(unsigned short evtchn, unsigned short pirq,
156                                     unsigned short gsi, unsigned short vector)
157 {
158         return (struct irq_info) { .type = IRQT_PIRQ, .evtchn = evtchn,
159                         .cpu = 0,
160                         .u.pirq = { .pirq = pirq, .gsi = gsi, .vector = vector } };
161 }
162
163 /*
164  * Accessors for packed IRQ information.
165  */
166 static struct irq_info *info_for_irq(unsigned irq)
167 {
168         return &irq_info[irq];
169 }
170
171 static unsigned int evtchn_from_irq(unsigned irq)
172 {
173         if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq)))
174                 return 0;
175
176         return info_for_irq(irq)->evtchn;
177 }
178
179 unsigned irq_from_evtchn(unsigned int evtchn)
180 {
181         return evtchn_to_irq[evtchn];
182 }
183 EXPORT_SYMBOL_GPL(irq_from_evtchn);
184
185 static enum ipi_vector ipi_from_irq(unsigned irq)
186 {
187         struct irq_info *info = info_for_irq(irq);
188
189         BUG_ON(info == NULL);
190         BUG_ON(info->type != IRQT_IPI);
191
192         return info->u.ipi;
193 }
194
195 static unsigned virq_from_irq(unsigned irq)
196 {
197         struct irq_info *info = info_for_irq(irq);
198
199         BUG_ON(info == NULL);
200         BUG_ON(info->type != IRQT_VIRQ);
201
202         return info->u.virq;
203 }
204
205 static unsigned pirq_from_irq(unsigned irq)
206 {
207         struct irq_info *info = info_for_irq(irq);
208
209         BUG_ON(info == NULL);
210         BUG_ON(info->type != IRQT_PIRQ);
211
212         return info->u.pirq.pirq;
213 }
214
215 static unsigned gsi_from_irq(unsigned irq)
216 {
217         struct irq_info *info = info_for_irq(irq);
218
219         BUG_ON(info == NULL);
220         BUG_ON(info->type != IRQT_PIRQ);
221
222         return info->u.pirq.gsi;
223 }
224
225 static unsigned vector_from_irq(unsigned irq)
226 {
227         struct irq_info *info = info_for_irq(irq);
228
229         BUG_ON(info == NULL);
230         BUG_ON(info->type != IRQT_PIRQ);
231
232         return info->u.pirq.vector;
233 }
234
235 static enum xen_irq_type type_from_irq(unsigned irq)
236 {
237         return info_for_irq(irq)->type;
238 }
239
240 static unsigned cpu_from_irq(unsigned irq)
241 {
242         return info_for_irq(irq)->cpu;
243 }
244
245 static unsigned int cpu_from_evtchn(unsigned int evtchn)
246 {
247         int irq = evtchn_to_irq[evtchn];
248         unsigned ret = 0;
249
250         if (irq != -1)
251                 ret = cpu_from_irq(irq);
252
253         return ret;
254 }
255
256 static bool pirq_needs_eoi(unsigned irq)
257 {
258         struct irq_info *info = info_for_irq(irq);
259
260         BUG_ON(info->type != IRQT_PIRQ);
261
262         return info->u.pirq.flags & PIRQ_NEEDS_EOI;
263 }
264
265 static inline unsigned long active_evtchns(unsigned int cpu,
266                                            struct shared_info *sh,
267                                            unsigned int idx)
268 {
269         return (sh->evtchn_pending[idx] &
270                 cpu_evtchn_mask(cpu)[idx] &
271                 ~sh->evtchn_mask[idx]);
272 }
273
274 static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
275 {
276         int irq = evtchn_to_irq[chn];
277
278         BUG_ON(irq == -1);
279 #ifdef CONFIG_SMP
280         cpumask_copy(irq_to_desc(irq)->affinity, cpumask_of(cpu));
281 #endif
282
283         clear_bit(chn, cpu_evtchn_mask(cpu_from_irq(irq)));
284         set_bit(chn, cpu_evtchn_mask(cpu));
285
286         irq_info[irq].cpu = cpu;
287 }
288
289 static void init_evtchn_cpu_bindings(void)
290 {
291         int i;
292 #ifdef CONFIG_SMP
293         struct irq_desc *desc;
294
295         /* By default all event channels notify CPU#0. */
296         for_each_irq_desc(i, desc) {
297                 cpumask_copy(desc->affinity, cpumask_of(0));
298         }
299 #endif
300
301         for_each_possible_cpu(i)
302                 memset(cpu_evtchn_mask(i),
303                        (i == 0) ? ~0 : 0, sizeof(struct cpu_evtchn_s));
304
305 }
306
307 static inline void clear_evtchn(int port)
308 {
309         struct shared_info *s = HYPERVISOR_shared_info;
310         sync_clear_bit(port, &s->evtchn_pending[0]);
311 }
312
313 static inline void set_evtchn(int port)
314 {
315         struct shared_info *s = HYPERVISOR_shared_info;
316         sync_set_bit(port, &s->evtchn_pending[0]);
317 }
318
319 static inline int test_evtchn(int port)
320 {
321         struct shared_info *s = HYPERVISOR_shared_info;
322         return sync_test_bit(port, &s->evtchn_pending[0]);
323 }
324
325
326 /**
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
329  *
330  * Unlike notify_remote_via_evtchn(), this is safe to use across
331  * save/restore. Notifications on a broken connection are silently
332  * dropped.
333  */
334 void notify_remote_via_irq(int irq)
335 {
336         int evtchn = evtchn_from_irq(irq);
337
338         if (VALID_EVTCHN(evtchn))
339                 notify_remote_via_evtchn(evtchn);
340 }
341 EXPORT_SYMBOL_GPL(notify_remote_via_irq);
342
343 static void mask_evtchn(int port)
344 {
345         struct shared_info *s = HYPERVISOR_shared_info;
346         sync_set_bit(port, &s->evtchn_mask[0]);
347 }
348
349 static void unmask_evtchn(int port)
350 {
351         struct shared_info *s = HYPERVISOR_shared_info;
352         unsigned int cpu = get_cpu();
353
354         BUG_ON(!irqs_disabled());
355
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);
360         } else {
361                 struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
362
363                 sync_clear_bit(port, &s->evtchn_mask[0]);
364
365                 /*
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.
369                  */
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;
374         }
375
376         put_cpu();
377 }
378
379 static int get_nr_hw_irqs(void)
380 {
381         int ret = 1;
382
383 #ifdef CONFIG_X86_IO_APIC
384         ret = get_nr_irqs_gsi();
385 #endif
386
387         return ret;
388 }
389
390 static int find_unbound_pirq(int type)
391 {
392         int rc, i;
393         struct physdev_get_free_pirq op_get_free_pirq;
394         op_get_free_pirq.type = type;
395
396         rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);
397         if (!rc)
398                 return op_get_free_pirq.pirq;
399
400         for (i = 0; i < nr_irqs; i++) {
401                 if (pirq_to_irq[i] < 0)
402                         return i;
403         }
404         return -1;
405 }
406
407 static int find_unbound_irq(void)
408 {
409         struct irq_data *data;
410         int irq, res;
411         int bottom = get_nr_hw_irqs();
412         int top = nr_irqs-1;
413
414         if (bottom == nr_irqs)
415                 goto no_irqs;
416
417         /* This loop starts from the top of IRQ space and goes down.
418          * We need this b/c if we have a PCI device in a Xen PV guest
419          * we do not have an IO-APIC (though the backend might have them)
420          * mapped in. To not have a collision of physical IRQs with the Xen
421          * event channels start at the top of the IRQ space for virtual IRQs.
422          */
423         for (irq = top; irq > bottom; irq--) {
424                 data = irq_get_irq_data(irq);
425                 /* only 15->0 have init'd desc; handle irq > 16 */
426                 if (!data)
427                         break;
428                 if (data->chip == &no_irq_chip)
429                         break;
430                 if (data->chip != &xen_dynamic_chip)
431                         continue;
432                 if (irq_info[irq].type == IRQT_UNBOUND)
433                         return irq;
434         }
435
436         if (irq == bottom)
437                 goto no_irqs;
438
439         res = irq_alloc_desc_at(irq, -1);
440
441         if (WARN_ON(res != irq))
442                 return -1;
443
444         return irq;
445
446 no_irqs:
447         panic("No available IRQ to bind to: increase nr_irqs!\n");
448 }
449
450 static bool identity_mapped_irq(unsigned irq)
451 {
452         /* identity map all the hardware irqs */
453         return irq < get_nr_hw_irqs();
454 }
455
456 static void pirq_unmask_notify(int irq)
457 {
458         struct physdev_eoi eoi = { .irq = pirq_from_irq(irq) };
459
460         if (unlikely(pirq_needs_eoi(irq))) {
461                 int rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
462                 WARN_ON(rc);
463         }
464 }
465
466 static void pirq_query_unmask(int irq)
467 {
468         struct physdev_irq_status_query irq_status;
469         struct irq_info *info = info_for_irq(irq);
470
471         BUG_ON(info->type != IRQT_PIRQ);
472
473         irq_status.irq = pirq_from_irq(irq);
474         if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
475                 irq_status.flags = 0;
476
477         info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
478         if (irq_status.flags & XENIRQSTAT_needs_eoi)
479                 info->u.pirq.flags |= PIRQ_NEEDS_EOI;
480 }
481
482 static bool probing_irq(int irq)
483 {
484         struct irq_desc *desc = irq_to_desc(irq);
485
486         return desc && desc->action == NULL;
487 }
488
489 static unsigned int startup_pirq(unsigned int irq)
490 {
491         struct evtchn_bind_pirq bind_pirq;
492         struct irq_info *info = info_for_irq(irq);
493         int evtchn = evtchn_from_irq(irq);
494         int rc;
495
496         BUG_ON(info->type != IRQT_PIRQ);
497
498         if (VALID_EVTCHN(evtchn))
499                 goto out;
500
501         bind_pirq.pirq = pirq_from_irq(irq);
502         /* NB. We are happy to share unless we are probing. */
503         bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
504                                         BIND_PIRQ__WILL_SHARE : 0;
505         rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
506         if (rc != 0) {
507                 if (!probing_irq(irq))
508                         printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
509                                irq);
510                 return 0;
511         }
512         evtchn = bind_pirq.port;
513
514         pirq_query_unmask(irq);
515
516         evtchn_to_irq[evtchn] = irq;
517         bind_evtchn_to_cpu(evtchn, 0);
518         info->evtchn = evtchn;
519
520 out:
521         unmask_evtchn(evtchn);
522         pirq_unmask_notify(irq);
523
524         return 0;
525 }
526
527 static void shutdown_pirq(unsigned int irq)
528 {
529         struct evtchn_close close;
530         struct irq_info *info = info_for_irq(irq);
531         int evtchn = evtchn_from_irq(irq);
532
533         BUG_ON(info->type != IRQT_PIRQ);
534
535         if (!VALID_EVTCHN(evtchn))
536                 return;
537
538         mask_evtchn(evtchn);
539
540         close.port = evtchn;
541         if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
542                 BUG();
543
544         bind_evtchn_to_cpu(evtchn, 0);
545         evtchn_to_irq[evtchn] = -1;
546         info->evtchn = 0;
547 }
548
549 static void enable_pirq(unsigned int irq)
550 {
551         startup_pirq(irq);
552 }
553
554 static void disable_pirq(unsigned int irq)
555 {
556 }
557
558 static void ack_pirq(unsigned int irq)
559 {
560         int evtchn = evtchn_from_irq(irq);
561
562         move_native_irq(irq);
563
564         if (VALID_EVTCHN(evtchn)) {
565                 mask_evtchn(evtchn);
566                 clear_evtchn(evtchn);
567         }
568 }
569
570 static void end_pirq(unsigned int irq)
571 {
572         int evtchn = evtchn_from_irq(irq);
573         struct irq_desc *desc = irq_to_desc(irq);
574
575         if (WARN_ON(!desc))
576                 return;
577
578         if ((desc->status & (IRQ_DISABLED|IRQ_PENDING)) ==
579             (IRQ_DISABLED|IRQ_PENDING)) {
580                 shutdown_pirq(irq);
581         } else if (VALID_EVTCHN(evtchn)) {
582                 unmask_evtchn(evtchn);
583                 pirq_unmask_notify(irq);
584         }
585 }
586
587 static int find_irq_by_gsi(unsigned gsi)
588 {
589         int irq;
590
591         for (irq = 0; irq < nr_irqs; irq++) {
592                 struct irq_info *info = info_for_irq(irq);
593
594                 if (info == NULL || info->type != IRQT_PIRQ)
595                         continue;
596
597                 if (gsi_from_irq(irq) == gsi)
598                         return irq;
599         }
600
601         return -1;
602 }
603
604 int xen_allocate_pirq(unsigned gsi, int shareable, char *name)
605 {
606         return xen_map_pirq_gsi(gsi, gsi, shareable, name);
607 }
608
609 /* xen_map_pirq_gsi might allocate irqs from the top down, as a
610  * consequence don't assume that the irq number returned has a low value
611  * or can be used as a pirq number unless you know otherwise.
612  *
613  * One notable exception is when xen_map_pirq_gsi is called passing an
614  * hardware gsi as argument, in that case the irq number returned
615  * matches the gsi number passed as second argument.
616  *
617  * Note: We don't assign an event channel until the irq actually started
618  * up.  Return an existing irq if we've already got one for the gsi.
619  */
620 int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)
621 {
622         int irq = 0;
623         struct physdev_irq irq_op;
624
625         spin_lock(&irq_mapping_update_lock);
626
627         if ((pirq > nr_irqs) || (gsi > nr_irqs)) {
628                 printk(KERN_WARNING "xen_map_pirq_gsi: %s %s is incorrect!\n",
629                         pirq > nr_irqs ? "pirq" :"",
630                         gsi > nr_irqs ? "gsi" : "");
631                 goto out;
632         }
633
634         irq = find_irq_by_gsi(gsi);
635         if (irq != -1) {
636                 printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n",
637                        irq, gsi);
638                 goto out;       /* XXX need refcount? */
639         }
640
641         /* If we are a PV guest, we don't have GSIs (no ACPI passed). Therefore
642          * we are using the !xen_initial_domain() to drop in the function.*/
643         if (identity_mapped_irq(gsi) || (!xen_initial_domain() &&
644                                 xen_pv_domain())) {
645                 irq = gsi;
646                 irq_alloc_desc_at(irq, -1);
647         } else
648                 irq = find_unbound_irq();
649
650         set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
651                                       handle_level_irq, name);
652
653         irq_op.irq = irq;
654         irq_op.vector = 0;
655
656         /* Only the privileged domain can do this. For non-priv, the pcifront
657          * driver provides a PCI bus that does the call to do exactly
658          * this in the priv domain. */
659         if (xen_initial_domain() &&
660             HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
661                 irq_free_desc(irq);
662                 irq = -ENOSPC;
663                 goto out;
664         }
665
666         irq_info[irq] = mk_pirq_info(0, pirq, gsi, irq_op.vector);
667         irq_info[irq].u.pirq.flags |= shareable ? PIRQ_SHAREABLE : 0;
668         pirq_to_irq[pirq] = irq;
669
670 out:
671         spin_unlock(&irq_mapping_update_lock);
672
673         return irq;
674 }
675
676 #ifdef CONFIG_PCI_MSI
677 #include <linux/msi.h>
678 #include "../pci/msi.h"
679
680 void xen_allocate_pirq_msi(char *name, int *irq, int *pirq, int alloc)
681 {
682         spin_lock(&irq_mapping_update_lock);
683
684         if (alloc & XEN_ALLOC_IRQ) {
685                 *irq = find_unbound_irq();
686                 if (*irq == -1)
687                         goto out;
688         }
689
690         if (alloc & XEN_ALLOC_PIRQ) {
691                 *pirq = find_unbound_pirq(MAP_PIRQ_TYPE_MSI);
692                 if (*pirq == -1)
693                         goto out;
694         }
695
696         set_irq_chip_and_handler_name(*irq, &xen_pirq_chip,
697                                       handle_level_irq, name);
698
699         irq_info[*irq] = mk_pirq_info(0, *pirq, 0, 0);
700         pirq_to_irq[*pirq] = *irq;
701
702 out:
703         spin_unlock(&irq_mapping_update_lock);
704 }
705
706 int xen_create_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int type)
707 {
708         int irq = -1;
709         struct physdev_map_pirq map_irq;
710         int rc;
711         int pos;
712         u32 table_offset, bir;
713
714         memset(&map_irq, 0, sizeof(map_irq));
715         map_irq.domid = DOMID_SELF;
716         map_irq.type = MAP_PIRQ_TYPE_MSI;
717         map_irq.index = -1;
718         map_irq.pirq = -1;
719         map_irq.bus = dev->bus->number;
720         map_irq.devfn = dev->devfn;
721
722         if (type == PCI_CAP_ID_MSIX) {
723                 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
724
725                 pci_read_config_dword(dev, msix_table_offset_reg(pos),
726                                         &table_offset);
727                 bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
728
729                 map_irq.table_base = pci_resource_start(dev, bir);
730                 map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
731         }
732
733         spin_lock(&irq_mapping_update_lock);
734
735         irq = find_unbound_irq();
736
737         if (irq == -1)
738                 goto out;
739
740         rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
741         if (rc) {
742                 printk(KERN_WARNING "xen map irq failed %d\n", rc);
743
744                 irq_free_desc(irq);
745
746                 irq = -1;
747                 goto out;
748         }
749         irq_info[irq] = mk_pirq_info(0, map_irq.pirq, 0, map_irq.index);
750
751         set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
752                         handle_level_irq,
753                         (type == PCI_CAP_ID_MSIX) ? "msi-x":"msi");
754
755 out:
756         spin_unlock(&irq_mapping_update_lock);
757         return irq;
758 }
759 #endif
760
761 int xen_destroy_irq(int irq)
762 {
763         struct irq_desc *desc;
764         struct physdev_unmap_pirq unmap_irq;
765         struct irq_info *info = info_for_irq(irq);
766         int rc = -ENOENT;
767
768         spin_lock(&irq_mapping_update_lock);
769
770         desc = irq_to_desc(irq);
771         if (!desc)
772                 goto out;
773
774         if (xen_initial_domain()) {
775                 unmap_irq.pirq = info->u.pirq.pirq;
776                 unmap_irq.domid = DOMID_SELF;
777                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
778                 if (rc) {
779                         printk(KERN_WARNING "unmap irq failed %d\n", rc);
780                         goto out;
781                 }
782                 pirq_to_irq[info->u.pirq.pirq] = -1;
783         }
784         irq_info[irq] = mk_unbound_info();
785
786         irq_free_desc(irq);
787
788 out:
789         spin_unlock(&irq_mapping_update_lock);
790         return rc;
791 }
792
793 int xen_vector_from_irq(unsigned irq)
794 {
795         return vector_from_irq(irq);
796 }
797
798 int xen_gsi_from_irq(unsigned irq)
799 {
800         return gsi_from_irq(irq);
801 }
802
803 int xen_irq_from_pirq(unsigned pirq)
804 {
805         return pirq_to_irq[pirq];
806 }
807
808 int bind_evtchn_to_irq(unsigned int evtchn)
809 {
810         int irq;
811
812         spin_lock(&irq_mapping_update_lock);
813
814         irq = evtchn_to_irq[evtchn];
815
816         if (irq == -1) {
817                 irq = find_unbound_irq();
818
819                 set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
820                                               handle_fasteoi_irq, "event");
821
822                 evtchn_to_irq[evtchn] = irq;
823                 irq_info[irq] = mk_evtchn_info(evtchn);
824         }
825
826         spin_unlock(&irq_mapping_update_lock);
827
828         return irq;
829 }
830 EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
831
832 static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
833 {
834         struct evtchn_bind_ipi bind_ipi;
835         int evtchn, irq;
836
837         spin_lock(&irq_mapping_update_lock);
838
839         irq = per_cpu(ipi_to_irq, cpu)[ipi];
840
841         if (irq == -1) {
842                 irq = find_unbound_irq();
843                 if (irq < 0)
844                         goto out;
845
846                 set_irq_chip_and_handler_name(irq, &xen_percpu_chip,
847                                               handle_percpu_irq, "ipi");
848
849                 bind_ipi.vcpu = cpu;
850                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
851                                                 &bind_ipi) != 0)
852                         BUG();
853                 evtchn = bind_ipi.port;
854
855                 evtchn_to_irq[evtchn] = irq;
856                 irq_info[irq] = mk_ipi_info(evtchn, ipi);
857                 per_cpu(ipi_to_irq, cpu)[ipi] = irq;
858
859                 bind_evtchn_to_cpu(evtchn, cpu);
860         }
861
862  out:
863         spin_unlock(&irq_mapping_update_lock);
864         return irq;
865 }
866
867
868 int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
869 {
870         struct evtchn_bind_virq bind_virq;
871         int evtchn, irq;
872
873         spin_lock(&irq_mapping_update_lock);
874
875         irq = per_cpu(virq_to_irq, cpu)[virq];
876
877         if (irq == -1) {
878                 irq = find_unbound_irq();
879
880                 set_irq_chip_and_handler_name(irq, &xen_percpu_chip,
881                                               handle_percpu_irq, "virq");
882
883                 bind_virq.virq = virq;
884                 bind_virq.vcpu = cpu;
885                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
886                                                 &bind_virq) != 0)
887                         BUG();
888                 evtchn = bind_virq.port;
889
890                 evtchn_to_irq[evtchn] = irq;
891                 irq_info[irq] = mk_virq_info(evtchn, virq);
892
893                 per_cpu(virq_to_irq, cpu)[virq] = irq;
894
895                 bind_evtchn_to_cpu(evtchn, cpu);
896         }
897
898         spin_unlock(&irq_mapping_update_lock);
899
900         return irq;
901 }
902
903 static void unbind_from_irq(unsigned int irq)
904 {
905         struct evtchn_close close;
906         int evtchn = evtchn_from_irq(irq);
907
908         spin_lock(&irq_mapping_update_lock);
909
910         if (VALID_EVTCHN(evtchn)) {
911                 close.port = evtchn;
912                 if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
913                         BUG();
914
915                 switch (type_from_irq(irq)) {
916                 case IRQT_VIRQ:
917                         per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
918                                 [virq_from_irq(irq)] = -1;
919                         break;
920                 case IRQT_IPI:
921                         per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
922                                 [ipi_from_irq(irq)] = -1;
923                         break;
924                 default:
925                         break;
926                 }
927
928                 /* Closed ports are implicitly re-bound to VCPU0. */
929                 bind_evtchn_to_cpu(evtchn, 0);
930
931                 evtchn_to_irq[evtchn] = -1;
932         }
933
934         if (irq_info[irq].type != IRQT_UNBOUND) {
935                 irq_info[irq] = mk_unbound_info();
936
937                 irq_free_desc(irq);
938         }
939
940         spin_unlock(&irq_mapping_update_lock);
941 }
942
943 int bind_evtchn_to_irqhandler(unsigned int evtchn,
944                               irq_handler_t handler,
945                               unsigned long irqflags,
946                               const char *devname, void *dev_id)
947 {
948         unsigned int irq;
949         int retval;
950
951         irq = bind_evtchn_to_irq(evtchn);
952         retval = request_irq(irq, handler, irqflags, devname, dev_id);
953         if (retval != 0) {
954                 unbind_from_irq(irq);
955                 return retval;
956         }
957
958         return irq;
959 }
960 EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler);
961
962 int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
963                             irq_handler_t handler,
964                             unsigned long irqflags, const char *devname, void *dev_id)
965 {
966         unsigned int irq;
967         int retval;
968
969         irq = bind_virq_to_irq(virq, cpu);
970         retval = request_irq(irq, handler, irqflags, devname, dev_id);
971         if (retval != 0) {
972                 unbind_from_irq(irq);
973                 return retval;
974         }
975
976         return irq;
977 }
978 EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);
979
980 int bind_ipi_to_irqhandler(enum ipi_vector ipi,
981                            unsigned int cpu,
982                            irq_handler_t handler,
983                            unsigned long irqflags,
984                            const char *devname,
985                            void *dev_id)
986 {
987         int irq, retval;
988
989         irq = bind_ipi_to_irq(ipi, cpu);
990         if (irq < 0)
991                 return irq;
992
993         irqflags |= IRQF_NO_SUSPEND;
994         retval = request_irq(irq, handler, irqflags, devname, dev_id);
995         if (retval != 0) {
996                 unbind_from_irq(irq);
997                 return retval;
998         }
999
1000         return irq;
1001 }
1002
1003 void unbind_from_irqhandler(unsigned int irq, void *dev_id)
1004 {
1005         free_irq(irq, dev_id);
1006         unbind_from_irq(irq);
1007 }
1008 EXPORT_SYMBOL_GPL(unbind_from_irqhandler);
1009
1010 void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
1011 {
1012         int irq = per_cpu(ipi_to_irq, cpu)[vector];
1013         BUG_ON(irq < 0);
1014         notify_remote_via_irq(irq);
1015 }
1016
1017 irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
1018 {
1019         struct shared_info *sh = HYPERVISOR_shared_info;
1020         int cpu = smp_processor_id();
1021         unsigned long *cpu_evtchn = cpu_evtchn_mask(cpu);
1022         int i;
1023         unsigned long flags;
1024         static DEFINE_SPINLOCK(debug_lock);
1025         struct vcpu_info *v;
1026
1027         spin_lock_irqsave(&debug_lock, flags);
1028
1029         printk("\nvcpu %d\n  ", cpu);
1030
1031         for_each_online_cpu(i) {
1032                 int pending;
1033                 v = per_cpu(xen_vcpu, i);
1034                 pending = (get_irq_regs() && i == cpu)
1035                         ? xen_irqs_disabled(get_irq_regs())
1036                         : v->evtchn_upcall_mask;
1037                 printk("%d: masked=%d pending=%d event_sel %0*lx\n  ", i,
1038                        pending, v->evtchn_upcall_pending,
1039                        (int)(sizeof(v->evtchn_pending_sel)*2),
1040                        v->evtchn_pending_sel);
1041         }
1042         v = per_cpu(xen_vcpu, cpu);
1043
1044         printk("\npending:\n   ");
1045         for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--)
1046                 printk("%0*lx%s", (int)sizeof(sh->evtchn_pending[0])*2,
1047                        sh->evtchn_pending[i],
1048                        i % 8 == 0 ? "\n   " : " ");
1049         printk("\nglobal mask:\n   ");
1050         for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
1051                 printk("%0*lx%s",
1052                        (int)(sizeof(sh->evtchn_mask[0])*2),
1053                        sh->evtchn_mask[i],
1054                        i % 8 == 0 ? "\n   " : " ");
1055
1056         printk("\nglobally unmasked:\n   ");
1057         for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
1058                 printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
1059                        sh->evtchn_pending[i] & ~sh->evtchn_mask[i],
1060                        i % 8 == 0 ? "\n   " : " ");
1061
1062         printk("\nlocal cpu%d mask:\n   ", cpu);
1063         for (i = (NR_EVENT_CHANNELS/BITS_PER_LONG)-1; i >= 0; i--)
1064                 printk("%0*lx%s", (int)(sizeof(cpu_evtchn[0])*2),
1065                        cpu_evtchn[i],
1066                        i % 8 == 0 ? "\n   " : " ");
1067
1068         printk("\nlocally unmasked:\n   ");
1069         for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) {
1070                 unsigned long pending = sh->evtchn_pending[i]
1071                         & ~sh->evtchn_mask[i]
1072                         & cpu_evtchn[i];
1073                 printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
1074                        pending, i % 8 == 0 ? "\n   " : " ");
1075         }
1076
1077         printk("\npending list:\n");
1078         for (i = 0; i < NR_EVENT_CHANNELS; i++) {
1079                 if (sync_test_bit(i, sh->evtchn_pending)) {
1080                         int word_idx = i / BITS_PER_LONG;
1081                         printk("  %d: event %d -> irq %d%s%s%s\n",
1082                                cpu_from_evtchn(i), i,
1083                                evtchn_to_irq[i],
1084                                sync_test_bit(word_idx, &v->evtchn_pending_sel)
1085                                              ? "" : " l2-clear",
1086                                !sync_test_bit(i, sh->evtchn_mask)
1087                                              ? "" : " globally-masked",
1088                                sync_test_bit(i, cpu_evtchn)
1089                                              ? "" : " locally-masked");
1090                 }
1091         }
1092
1093         spin_unlock_irqrestore(&debug_lock, flags);
1094
1095         return IRQ_HANDLED;
1096 }
1097
1098 static DEFINE_PER_CPU(unsigned, xed_nesting_count);
1099
1100 /*
1101  * Search the CPUs pending events bitmasks.  For each one found, map
1102  * the event number to an irq, and feed it into do_IRQ() for
1103  * handling.
1104  *
1105  * Xen uses a two-level bitmap to speed searching.  The first level is
1106  * a bitset of words which contain pending event bits.  The second
1107  * level is a bitset of pending events themselves.
1108  */
1109 static void __xen_evtchn_do_upcall(void)
1110 {
1111         int cpu = get_cpu();
1112         struct shared_info *s = HYPERVISOR_shared_info;
1113         struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
1114         unsigned count;
1115
1116         do {
1117                 unsigned long pending_words;
1118
1119                 vcpu_info->evtchn_upcall_pending = 0;
1120
1121                 if (__this_cpu_inc_return(xed_nesting_count) - 1)
1122                         goto out;
1123
1124 #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
1125                 /* Clear master flag /before/ clearing selector flag. */
1126                 wmb();
1127 #endif
1128                 pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
1129                 while (pending_words != 0) {
1130                         unsigned long pending_bits;
1131                         int word_idx = __ffs(pending_words);
1132                         pending_words &= ~(1UL << word_idx);
1133
1134                         while ((pending_bits = active_evtchns(cpu, s, word_idx)) != 0) {
1135                                 int bit_idx = __ffs(pending_bits);
1136                                 int port = (word_idx * BITS_PER_LONG) + bit_idx;
1137                                 int irq = evtchn_to_irq[port];
1138                                 struct irq_desc *desc;
1139
1140                                 mask_evtchn(port);
1141                                 clear_evtchn(port);
1142
1143                                 if (irq != -1) {
1144                                         desc = irq_to_desc(irq);
1145                                         if (desc)
1146                                                 generic_handle_irq_desc(irq, desc);
1147                                 }
1148                         }
1149                 }
1150
1151                 BUG_ON(!irqs_disabled());
1152
1153                 count = __this_cpu_read(xed_nesting_count);
1154                 __this_cpu_write(xed_nesting_count, 0);
1155         } while (count != 1 || vcpu_info->evtchn_upcall_pending);
1156
1157 out:
1158
1159         put_cpu();
1160 }
1161
1162 void xen_evtchn_do_upcall(struct pt_regs *regs)
1163 {
1164         struct pt_regs *old_regs = set_irq_regs(regs);
1165
1166         exit_idle();
1167         irq_enter();
1168
1169         __xen_evtchn_do_upcall();
1170
1171         irq_exit();
1172         set_irq_regs(old_regs);
1173 }
1174
1175 void xen_hvm_evtchn_do_upcall(void)
1176 {
1177         __xen_evtchn_do_upcall();
1178 }
1179 EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall);
1180
1181 /* Rebind a new event channel to an existing irq. */
1182 void rebind_evtchn_irq(int evtchn, int irq)
1183 {
1184         struct irq_info *info = info_for_irq(irq);
1185
1186         /* Make sure the irq is masked, since the new event channel
1187            will also be masked. */
1188         disable_irq(irq);
1189
1190         spin_lock(&irq_mapping_update_lock);
1191
1192         /* After resume the irq<->evtchn mappings are all cleared out */
1193         BUG_ON(evtchn_to_irq[evtchn] != -1);
1194         /* Expect irq to have been bound before,
1195            so there should be a proper type */
1196         BUG_ON(info->type == IRQT_UNBOUND);
1197
1198         evtchn_to_irq[evtchn] = irq;
1199         irq_info[irq] = mk_evtchn_info(evtchn);
1200
1201         spin_unlock(&irq_mapping_update_lock);
1202
1203         /* new event channels are always bound to cpu 0 */
1204         irq_set_affinity(irq, cpumask_of(0));
1205
1206         /* Unmask the event channel. */
1207         enable_irq(irq);
1208 }
1209
1210 /* Rebind an evtchn so that it gets delivered to a specific cpu */
1211 static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
1212 {
1213         struct evtchn_bind_vcpu bind_vcpu;
1214         int evtchn = evtchn_from_irq(irq);
1215
1216         /* events delivered via platform PCI interrupts are always
1217          * routed to vcpu 0 */
1218         if (!VALID_EVTCHN(evtchn) ||
1219                 (xen_hvm_domain() && !xen_have_vector_callback))
1220                 return -1;
1221
1222         /* Send future instances of this interrupt to other vcpu. */
1223         bind_vcpu.port = evtchn;
1224         bind_vcpu.vcpu = tcpu;
1225
1226         /*
1227          * If this fails, it usually just indicates that we're dealing with a
1228          * virq or IPI channel, which don't actually need to be rebound. Ignore
1229          * it, but don't do the xenlinux-level rebind in that case.
1230          */
1231         if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
1232                 bind_evtchn_to_cpu(evtchn, tcpu);
1233
1234         return 0;
1235 }
1236
1237 static int set_affinity_irq(unsigned irq, const struct cpumask *dest)
1238 {
1239         unsigned tcpu = cpumask_first(dest);
1240
1241         return rebind_irq_to_cpu(irq, tcpu);
1242 }
1243
1244 int resend_irq_on_evtchn(unsigned int irq)
1245 {
1246         int masked, evtchn = evtchn_from_irq(irq);
1247         struct shared_info *s = HYPERVISOR_shared_info;
1248
1249         if (!VALID_EVTCHN(evtchn))
1250                 return 1;
1251
1252         masked = sync_test_and_set_bit(evtchn, s->evtchn_mask);
1253         sync_set_bit(evtchn, s->evtchn_pending);
1254         if (!masked)
1255                 unmask_evtchn(evtchn);
1256
1257         return 1;
1258 }
1259
1260 static void enable_dynirq(unsigned int irq)
1261 {
1262         int evtchn = evtchn_from_irq(irq);
1263
1264         if (VALID_EVTCHN(evtchn))
1265                 unmask_evtchn(evtchn);
1266 }
1267
1268 static void disable_dynirq(unsigned int irq)
1269 {
1270         int evtchn = evtchn_from_irq(irq);
1271
1272         if (VALID_EVTCHN(evtchn))
1273                 mask_evtchn(evtchn);
1274 }
1275
1276 static void ack_dynirq(unsigned int irq)
1277 {
1278         int evtchn = evtchn_from_irq(irq);
1279
1280         move_masked_irq(irq);
1281
1282         if (VALID_EVTCHN(evtchn))
1283                 unmask_evtchn(evtchn);
1284 }
1285
1286 static int retrigger_dynirq(unsigned int irq)
1287 {
1288         int evtchn = evtchn_from_irq(irq);
1289         struct shared_info *sh = HYPERVISOR_shared_info;
1290         int ret = 0;
1291
1292         if (VALID_EVTCHN(evtchn)) {
1293                 int masked;
1294
1295                 masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask);
1296                 sync_set_bit(evtchn, sh->evtchn_pending);
1297                 if (!masked)
1298                         unmask_evtchn(evtchn);
1299                 ret = 1;
1300         }
1301
1302         return ret;
1303 }
1304
1305 static void restore_cpu_pirqs(void)
1306 {
1307         int pirq, rc, irq, gsi;
1308         struct physdev_map_pirq map_irq;
1309
1310         for (pirq = 0; pirq < nr_irqs; pirq++) {
1311                 irq = pirq_to_irq[pirq];
1312                 if (irq == -1)
1313                         continue;
1314
1315                 /* save/restore of PT devices doesn't work, so at this point the
1316                  * only devices present are GSI based emulated devices */
1317                 gsi = gsi_from_irq(irq);
1318                 if (!gsi)
1319                         continue;
1320
1321                 map_irq.domid = DOMID_SELF;
1322                 map_irq.type = MAP_PIRQ_TYPE_GSI;
1323                 map_irq.index = gsi;
1324                 map_irq.pirq = pirq;
1325
1326                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
1327                 if (rc) {
1328                         printk(KERN_WARNING "xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
1329                                         gsi, irq, pirq, rc);
1330                         irq_info[irq] = mk_unbound_info();
1331                         pirq_to_irq[pirq] = -1;
1332                         continue;
1333                 }
1334
1335                 printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
1336
1337                 startup_pirq(irq);
1338         }
1339 }
1340
1341 static void restore_cpu_virqs(unsigned int cpu)
1342 {
1343         struct evtchn_bind_virq bind_virq;
1344         int virq, irq, evtchn;
1345
1346         for (virq = 0; virq < NR_VIRQS; virq++) {
1347                 if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1)
1348                         continue;
1349
1350                 BUG_ON(virq_from_irq(irq) != virq);
1351
1352                 /* Get a new binding from Xen. */
1353                 bind_virq.virq = virq;
1354                 bind_virq.vcpu = cpu;
1355                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
1356                                                 &bind_virq) != 0)
1357                         BUG();
1358                 evtchn = bind_virq.port;
1359
1360                 /* Record the new mapping. */
1361                 evtchn_to_irq[evtchn] = irq;
1362                 irq_info[irq] = mk_virq_info(evtchn, virq);
1363                 bind_evtchn_to_cpu(evtchn, cpu);
1364         }
1365 }
1366
1367 static void restore_cpu_ipis(unsigned int cpu)
1368 {
1369         struct evtchn_bind_ipi bind_ipi;
1370         int ipi, irq, evtchn;
1371
1372         for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) {
1373                 if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1)
1374                         continue;
1375
1376                 BUG_ON(ipi_from_irq(irq) != ipi);
1377
1378                 /* Get a new binding from Xen. */
1379                 bind_ipi.vcpu = cpu;
1380                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
1381                                                 &bind_ipi) != 0)
1382                         BUG();
1383                 evtchn = bind_ipi.port;
1384
1385                 /* Record the new mapping. */
1386                 evtchn_to_irq[evtchn] = irq;
1387                 irq_info[irq] = mk_ipi_info(evtchn, ipi);
1388                 bind_evtchn_to_cpu(evtchn, cpu);
1389         }
1390 }
1391
1392 /* Clear an irq's pending state, in preparation for polling on it */
1393 void xen_clear_irq_pending(int irq)
1394 {
1395         int evtchn = evtchn_from_irq(irq);
1396
1397         if (VALID_EVTCHN(evtchn))
1398                 clear_evtchn(evtchn);
1399 }
1400 EXPORT_SYMBOL(xen_clear_irq_pending);
1401 void xen_set_irq_pending(int irq)
1402 {
1403         int evtchn = evtchn_from_irq(irq);
1404
1405         if (VALID_EVTCHN(evtchn))
1406                 set_evtchn(evtchn);
1407 }
1408
1409 bool xen_test_irq_pending(int irq)
1410 {
1411         int evtchn = evtchn_from_irq(irq);
1412         bool ret = false;
1413
1414         if (VALID_EVTCHN(evtchn))
1415                 ret = test_evtchn(evtchn);
1416
1417         return ret;
1418 }
1419
1420 /* Poll waiting for an irq to become pending with timeout.  In the usual case,
1421  * the irq will be disabled so it won't deliver an interrupt. */
1422 void xen_poll_irq_timeout(int irq, u64 timeout)
1423 {
1424         evtchn_port_t evtchn = evtchn_from_irq(irq);
1425
1426         if (VALID_EVTCHN(evtchn)) {
1427                 struct sched_poll poll;
1428
1429                 poll.nr_ports = 1;
1430                 poll.timeout = timeout;
1431                 set_xen_guest_handle(poll.ports, &evtchn);
1432
1433                 if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
1434                         BUG();
1435         }
1436 }
1437 EXPORT_SYMBOL(xen_poll_irq_timeout);
1438 /* Poll waiting for an irq to become pending.  In the usual case, the
1439  * irq will be disabled so it won't deliver an interrupt. */
1440 void xen_poll_irq(int irq)
1441 {
1442         xen_poll_irq_timeout(irq, 0 /* no timeout */);
1443 }
1444
1445 void xen_irq_resume(void)
1446 {
1447         unsigned int cpu, irq, evtchn;
1448         struct irq_desc *desc;
1449
1450         init_evtchn_cpu_bindings();
1451
1452         /* New event-channel space is not 'live' yet. */
1453         for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
1454                 mask_evtchn(evtchn);
1455
1456         /* No IRQ <-> event-channel mappings. */
1457         for (irq = 0; irq < nr_irqs; irq++)
1458                 irq_info[irq].evtchn = 0; /* zap event-channel binding */
1459
1460         for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
1461                 evtchn_to_irq[evtchn] = -1;
1462
1463         for_each_possible_cpu(cpu) {
1464                 restore_cpu_virqs(cpu);
1465                 restore_cpu_ipis(cpu);
1466         }
1467
1468         /*
1469          * Unmask any IRQF_NO_SUSPEND IRQs which are enabled. These
1470          * are not handled by the IRQ core.
1471          */
1472         for_each_irq_desc(irq, desc) {
1473                 if (!desc->action || !(desc->action->flags & IRQF_NO_SUSPEND))
1474                         continue;
1475                 if (desc->status & IRQ_DISABLED)
1476                         continue;
1477
1478                 evtchn = evtchn_from_irq(irq);
1479                 if (evtchn == -1)
1480                         continue;
1481
1482                 unmask_evtchn(evtchn);
1483         }
1484
1485         restore_cpu_pirqs();
1486 }
1487
1488 static struct irq_chip xen_dynamic_chip __read_mostly = {
1489         .name           = "xen-dyn",
1490
1491         .disable        = disable_dynirq,
1492         .mask           = disable_dynirq,
1493         .unmask         = enable_dynirq,
1494
1495         .eoi            = ack_dynirq,
1496         .set_affinity   = set_affinity_irq,
1497         .retrigger      = retrigger_dynirq,
1498 };
1499
1500 static struct irq_chip xen_pirq_chip __read_mostly = {
1501         .name           = "xen-pirq",
1502
1503         .startup        = startup_pirq,
1504         .shutdown       = shutdown_pirq,
1505
1506         .enable         = enable_pirq,
1507         .unmask         = enable_pirq,
1508
1509         .disable        = disable_pirq,
1510         .mask           = disable_pirq,
1511
1512         .ack            = ack_pirq,
1513         .end            = end_pirq,
1514
1515         .set_affinity   = set_affinity_irq,
1516
1517         .retrigger      = retrigger_dynirq,
1518 };
1519
1520 static struct irq_chip xen_percpu_chip __read_mostly = {
1521         .name           = "xen-percpu",
1522
1523         .disable        = disable_dynirq,
1524         .mask           = disable_dynirq,
1525         .unmask         = enable_dynirq,
1526
1527         .ack            = ack_dynirq,
1528 };
1529
1530 int xen_set_callback_via(uint64_t via)
1531 {
1532         struct xen_hvm_param a;
1533         a.domid = DOMID_SELF;
1534         a.index = HVM_PARAM_CALLBACK_IRQ;
1535         a.value = via;
1536         return HYPERVISOR_hvm_op(HVMOP_set_param, &a);
1537 }
1538 EXPORT_SYMBOL_GPL(xen_set_callback_via);
1539
1540 #ifdef CONFIG_XEN_PVHVM
1541 /* Vector callbacks are better than PCI interrupts to receive event
1542  * channel notifications because we can receive vector callbacks on any
1543  * vcpu and we don't need PCI support or APIC interactions. */
1544 void xen_callback_vector(void)
1545 {
1546         int rc;
1547         uint64_t callback_via;
1548         if (xen_have_vector_callback) {
1549                 callback_via = HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK);
1550                 rc = xen_set_callback_via(callback_via);
1551                 if (rc) {
1552                         printk(KERN_ERR "Request for Xen HVM callback vector"
1553                                         " failed.\n");
1554                         xen_have_vector_callback = 0;
1555                         return;
1556                 }
1557                 printk(KERN_INFO "Xen HVM callback vector for event delivery is "
1558                                 "enabled\n");
1559                 /* in the restore case the vector has already been allocated */
1560                 if (!test_bit(XEN_HVM_EVTCHN_CALLBACK, used_vectors))
1561                         alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK, xen_hvm_callback_vector);
1562         }
1563 }
1564 #else
1565 void xen_callback_vector(void) {}
1566 #endif
1567
1568 void __init xen_init_IRQ(void)
1569 {
1570         int i;
1571
1572         cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s),
1573                                     GFP_KERNEL);
1574         irq_info = kcalloc(nr_irqs, sizeof(*irq_info), GFP_KERNEL);
1575
1576         /* We are using nr_irqs as the maximum number of pirq available but
1577          * that number is actually chosen by Xen and we don't know exactly
1578          * what it is. Be careful choosing high pirq numbers. */
1579         pirq_to_irq = kcalloc(nr_irqs, sizeof(*pirq_to_irq), GFP_KERNEL);
1580         for (i = 0; i < nr_irqs; i++)
1581                 pirq_to_irq[i] = -1;
1582
1583         evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
1584                                     GFP_KERNEL);
1585         for (i = 0; i < NR_EVENT_CHANNELS; i++)
1586                 evtchn_to_irq[i] = -1;
1587
1588         init_evtchn_cpu_bindings();
1589
1590         /* No event channels are 'live' right now. */
1591         for (i = 0; i < NR_EVENT_CHANNELS; i++)
1592                 mask_evtchn(i);
1593
1594         if (xen_hvm_domain()) {
1595                 xen_callback_vector();
1596                 native_init_IRQ();
1597                 /* pci_xen_hvm_init must be called after native_init_IRQ so that
1598                  * __acpi_register_gsi can point at the right function */
1599                 pci_xen_hvm_init();
1600         } else {
1601                 irq_ctx_init(smp_processor_id());
1602                 if (xen_initial_domain())
1603                         xen_setup_pirqs();
1604         }
1605 }