drivers/xen/events/events_base.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 #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt
  25
  26 #include <linux/linkage.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/irq.h>
  29 #include <linux/module.h>
  30 #include <linux/string.h>
  31 #include <linux/bootmem.h>
  32 #include <linux/slab.h>
  33 #include <linux/irqnr.h>
  34 #include <linux/pci.h>
  35
  36 #ifdef CONFIG_X86
  37 #include <asm/desc.h>
  38 #include <asm/ptrace.h>
  39 #include <asm/irq.h>
  40 #include <asm/idle.h>
  41 #include <asm/io_apic.h>
  42 #include <asm/xen/page.h>
  43 #include <asm/xen/pci.h>
  44 #endif
  45 #include <asm/sync_bitops.h>
  46 #include <asm/xen/hypercall.h>
  47 #include <asm/xen/hypervisor.h>
  48
  49 #include <xen/xen.h>
  50 #include <xen/hvm.h>
  51 #include <xen/xen-ops.h>
  52 #include <xen/events.h>
  53 #include <xen/interface/xen.h>
  54 #include <xen/interface/event_channel.h>
  55 #include <xen/interface/hvm/hvm_op.h>
  56 #include <xen/interface/hvm/params.h>
  57 #include <xen/interface/physdev.h>
  58 #include <xen/interface/sched.h>
  59 #include <xen/interface/vcpu.h>
  60 #include <asm/hw_irq.h>
  61
  62 #include "events_internal.h"
  63
  64 const struct evtchn_ops *evtchn_ops;
  65
  66 /*
  67  * This lock protects updates to the following mapping and reference-count
  68  * arrays. The lock does not need to be acquired to read the mapping tables.
  69  */
  70 static DEFINE_MUTEX(irq_mapping_update_lock);
  71
  72 static LIST_HEAD(xen_irq_list_head);
  73
  74 /* IRQ <-> VIRQ mapping. */
  75 static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1};
  76
  77 /* IRQ <-> IPI mapping */
  78 static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1};
  79
  80 int **evtchn_to_irq;
  81 #ifdef CONFIG_X86
  82 static unsigned long *pirq_eoi_map;
  83 #endif
  84 static bool (*pirq_needs_eoi)(unsigned irq);
  85
  86 #define EVTCHN_ROW(e)  (e / (PAGE_SIZE/sizeof(**evtchn_to_irq)))
  87 #define EVTCHN_COL(e)  (e % (PAGE_SIZE/sizeof(**evtchn_to_irq)))
  88 #define EVTCHN_PER_ROW (PAGE_SIZE / sizeof(**evtchn_to_irq))
  89
  90 /* Xen will never allocate port zero for any purpose. */
  91 #define VALID_EVTCHN(chn)       ((chn) != 0)
  92
  93 static struct irq_chip xen_dynamic_chip;
  94 static struct irq_chip xen_percpu_chip;
  95 static struct irq_chip xen_pirq_chip;
  96 static void enable_dynirq(struct irq_data *data);
  97 static void disable_dynirq(struct irq_data *data);
  98
  99 static void clear_evtchn_to_irq_row(unsigned row)
 100 {
 101         unsigned col;
 102
 103         for (col = 0; col < EVTCHN_PER_ROW; col++)
 104                 evtchn_to_irq[row][col] = -1;
 105 }
 106
 107 static void clear_evtchn_to_irq_all(void)
 108 {
 109         unsigned row;
 110
 111         for (row = 0; row < EVTCHN_ROW(xen_evtchn_max_channels()); row++) {
 112                 if (evtchn_to_irq[row] == NULL)
 113                         continue;
 114                 clear_evtchn_to_irq_row(row);
 115         }
 116 }
 117
 118 static int set_evtchn_to_irq(unsigned evtchn, unsigned irq)
 119 {
 120         unsigned row;
 121         unsigned col;
 122
 123         if (evtchn >= xen_evtchn_max_channels())
 124                 return -EINVAL;
 125
 126         row = EVTCHN_ROW(evtchn);
 127         col = EVTCHN_COL(evtchn);
 128
 129         if (evtchn_to_irq[row] == NULL) {
 130                 /* Unallocated irq entries return -1 anyway */
 131                 if (irq == -1)
 132                         return 0;
 133
 134                 evtchn_to_irq[row] = (int *)get_zeroed_page(GFP_KERNEL);
 135                 if (evtchn_to_irq[row] == NULL)
 136                         return -ENOMEM;
 137
 138                 clear_evtchn_to_irq_row(row);
 139         }
 140
 141         evtchn_to_irq[EVTCHN_ROW(evtchn)][EVTCHN_COL(evtchn)] = irq;
 142         return 0;
 143 }
 144
 145 int get_evtchn_to_irq(unsigned evtchn)
 146 {
 147         if (evtchn >= xen_evtchn_max_channels())
 148                 return -1;
 149         if (evtchn_to_irq[EVTCHN_ROW(evtchn)] == NULL)
 150                 return -1;
 151         return evtchn_to_irq[EVTCHN_ROW(evtchn)][EVTCHN_COL(evtchn)];
 152 }
 153
 154 /* Get info for IRQ */
 155 struct irq_info *info_for_irq(unsigned irq)
 156 {
 157         return irq_get_handler_data(irq);
 158 }
 159
 160 /* Constructors for packed IRQ information. */
 161 static int xen_irq_info_common_setup(struct irq_info *info,
 162                                      unsigned irq,
 163                                      enum xen_irq_type type,
 164                                      unsigned evtchn,
 165                                      unsigned short cpu)
 166 {
 167         int ret;
 168
 169         BUG_ON(info->type != IRQT_UNBOUND && info->type != type);
 170
 171         info->type = type;
 172         info->irq = irq;
 173         info->evtchn = evtchn;
 174         info->cpu = cpu;
 175
 176         ret = set_evtchn_to_irq(evtchn, irq);
 177         if (ret < 0)
 178                 return ret;
 179
 180         irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);
 181
 182         return xen_evtchn_port_setup(info);
 183 }
 184
 185 static int xen_irq_info_evtchn_setup(unsigned irq,
 186                                      unsigned evtchn)
 187 {
 188         struct irq_info *info = info_for_irq(irq);
 189
 190         return xen_irq_info_common_setup(info, irq, IRQT_EVTCHN, evtchn, 0);
 191 }
 192
 193 static int xen_irq_info_ipi_setup(unsigned cpu,
 194                                   unsigned irq,
 195                                   unsigned evtchn,
 196                                   enum ipi_vector ipi)
 197 {
 198         struct irq_info *info = info_for_irq(irq);
 199
 200         info->u.ipi = ipi;
 201
 202         per_cpu(ipi_to_irq, cpu)[ipi] = irq;
 203
 204         return xen_irq_info_common_setup(info, irq, IRQT_IPI, evtchn, 0);
 205 }
 206
 207 static int xen_irq_info_virq_setup(unsigned cpu,
 208                                    unsigned irq,
 209                                    unsigned evtchn,
 210                                    unsigned virq)
 211 {
 212         struct irq_info *info = info_for_irq(irq);
 213
 214         info->u.virq = virq;
 215
 216         per_cpu(virq_to_irq, cpu)[virq] = irq;
 217
 218         return xen_irq_info_common_setup(info, irq, IRQT_VIRQ, evtchn, 0);
 219 }
 220
 221 static int xen_irq_info_pirq_setup(unsigned irq,
 222                                    unsigned evtchn,
 223                                    unsigned pirq,
 224                                    unsigned gsi,
 225                                    uint16_t domid,
 226                                    unsigned char flags)
 227 {
 228         struct irq_info *info = info_for_irq(irq);
 229
 230         info->u.pirq.pirq = pirq;
 231         info->u.pirq.gsi = gsi;
 232         info->u.pirq.domid = domid;
 233         info->u.pirq.flags = flags;
 234
 235         return xen_irq_info_common_setup(info, irq, IRQT_PIRQ, evtchn, 0);
 236 }
 237
 238 static void xen_irq_info_cleanup(struct irq_info *info)
 239 {
 240         set_evtchn_to_irq(info->evtchn, -1);
 241         info->evtchn = 0;
 242 }
 243
 244 /*
 245  * Accessors for packed IRQ information.
 246  */
 247 unsigned int evtchn_from_irq(unsigned irq)
 248 {
 249         if (unlikely(WARN(irq >= nr_irqs, "Invalid irq %d!\n", irq)))
 250                 return 0;
 251
 252         return info_for_irq(irq)->evtchn;
 253 }
 254
 255 unsigned irq_from_evtchn(unsigned int evtchn)
 256 {
 257         return get_evtchn_to_irq(evtchn);
 258 }
 259 EXPORT_SYMBOL_GPL(irq_from_evtchn);
 260
 261 int irq_from_virq(unsigned int cpu, unsigned int virq)
 262 {
 263         return per_cpu(virq_to_irq, cpu)[virq];
 264 }
 265
 266 static enum ipi_vector ipi_from_irq(unsigned irq)
 267 {
 268         struct irq_info *info = info_for_irq(irq);
 269
 270         BUG_ON(info == NULL);
 271         BUG_ON(info->type != IRQT_IPI);
 272
 273         return info->u.ipi;
 274 }
 275
 276 static unsigned virq_from_irq(unsigned irq)
 277 {
 278         struct irq_info *info = info_for_irq(irq);
 279
 280         BUG_ON(info == NULL);
 281         BUG_ON(info->type != IRQT_VIRQ);
 282
 283         return info->u.virq;
 284 }
 285
 286 static unsigned pirq_from_irq(unsigned irq)
 287 {
 288         struct irq_info *info = info_for_irq(irq);
 289
 290         BUG_ON(info == NULL);
 291         BUG_ON(info->type != IRQT_PIRQ);
 292
 293         return info->u.pirq.pirq;
 294 }
 295
 296 static enum xen_irq_type type_from_irq(unsigned irq)
 297 {
 298         return info_for_irq(irq)->type;
 299 }
 300
 301 unsigned cpu_from_irq(unsigned irq)
 302 {
 303         return info_for_irq(irq)->cpu;
 304 }
 305
 306 unsigned int cpu_from_evtchn(unsigned int evtchn)
 307 {
 308         int irq = get_evtchn_to_irq(evtchn);
 309         unsigned ret = 0;
 310
 311         if (irq != -1)
 312                 ret = cpu_from_irq(irq);
 313
 314         return ret;
 315 }
 316
 317 #ifdef CONFIG_X86
 318 static bool pirq_check_eoi_map(unsigned irq)
 319 {
 320         return test_bit(pirq_from_irq(irq), pirq_eoi_map);
 321 }
 322 #endif
 323
 324 static bool pirq_needs_eoi_flag(unsigned irq)
 325 {
 326         struct irq_info *info = info_for_irq(irq);
 327         BUG_ON(info->type != IRQT_PIRQ);
 328
 329         return info->u.pirq.flags & PIRQ_NEEDS_EOI;
 330 }
 331
 332 static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
 333 {
 334         int irq = get_evtchn_to_irq(chn);
 335         struct irq_info *info = info_for_irq(irq);
 336
 337         BUG_ON(irq == -1);
 338 #ifdef CONFIG_SMP
 339         cpumask_copy(irq_get_irq_data(irq)->affinity, cpumask_of(cpu));
 340 #endif
 341         xen_evtchn_port_bind_to_cpu(info, cpu);
 342
 343         info->cpu = cpu;
 344 }
 345
 346 static void xen_evtchn_mask_all(void)
 347 {
 348         unsigned int evtchn;
 349
 350         for (evtchn = 0; evtchn < xen_evtchn_nr_channels(); evtchn++)
 351                 mask_evtchn(evtchn);
 352 }
 353
 354 /**
 355  * notify_remote_via_irq - send event to remote end of event channel via irq
 356  * @irq: irq of event channel to send event to
 357  *
 358  * Unlike notify_remote_via_evtchn(), this is safe to use across
 359  * save/restore. Notifications on a broken connection are silently
 360  * dropped.
 361  */
 362 void notify_remote_via_irq(int irq)
 363 {
 364         int evtchn = evtchn_from_irq(irq);
 365
 366         if (VALID_EVTCHN(evtchn))
 367                 notify_remote_via_evtchn(evtchn);
 368 }
 369 EXPORT_SYMBOL_GPL(notify_remote_via_irq);
 370
 371 static void xen_irq_init(unsigned irq)
 372 {
 373         struct irq_info *info;
 374 #ifdef CONFIG_SMP
 375         /* By default all event channels notify CPU#0. */
 376         cpumask_copy(irq_get_irq_data(irq)->affinity, cpumask_of(0));
 377 #endif
 378
 379         info = kzalloc(sizeof(*info), GFP_KERNEL);
 380         if (info == NULL)
 381                 panic("Unable to allocate metadata for IRQ%d\n", irq);
 382
 383         info->type = IRQT_UNBOUND;
 384         info->refcnt = -1;
 385
 386         irq_set_handler_data(irq, info);
 387
 388         list_add_tail(&info->list, &xen_irq_list_head);
 389 }
 390
 391 static int __must_check xen_allocate_irqs_dynamic(int nvec)
 392 {
 393         int i, irq = irq_alloc_descs(-1, 0, nvec, -1);
 394
 395         if (irq >= 0) {
 396                 for (i = 0; i < nvec; i++)
 397                         xen_irq_init(irq + i);
 398         }
 399
 400         return irq;
 401 }
 402
 403 static inline int __must_check xen_allocate_irq_dynamic(void)
 404 {
 405
 406         return xen_allocate_irqs_dynamic(1);
 407 }
 408
 409 static int __must_check xen_allocate_irq_gsi(unsigned gsi)
 410 {
 411         int irq;
 412
 413         /*
 414          * A PV guest has no concept of a GSI (since it has no ACPI
 415          * nor access to/knowledge of the physical APICs). Therefore
 416          * all IRQs are dynamically allocated from the entire IRQ
 417          * space.
 418          */
 419         if (xen_pv_domain() && !xen_initial_domain())
 420                 return xen_allocate_irq_dynamic();
 421
 422         /* Legacy IRQ descriptors are already allocated by the arch. */
 423         if (gsi < NR_IRQS_LEGACY)
 424                 irq = gsi;
 425         else
 426                 irq = irq_alloc_desc_at(gsi, -1);
 427
 428         xen_irq_init(irq);
 429
 430         return irq;
 431 }
 432
 433 static void xen_free_irq(unsigned irq)
 434 {
 435         struct irq_info *info = irq_get_handler_data(irq);
 436
 437         if (WARN_ON(!info))
 438                 return;
 439
 440         list_del(&info->list);
 441
 442         irq_set_handler_data(irq, NULL);
 443
 444         WARN_ON(info->refcnt > 0);
 445
 446         kfree(info);
 447
 448         /* Legacy IRQ descriptors are managed by the arch. */
 449         if (irq < NR_IRQS_LEGACY)
 450                 return;
 451
 452         irq_free_desc(irq);
 453 }
 454
 455 static void xen_evtchn_close(unsigned int port)
 456 {
 457         struct evtchn_close close;
 458
 459         close.port = port;
 460         if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
 461                 BUG();
 462 }
 463
 464 static void pirq_query_unmask(int irq)
 465 {
 466         struct physdev_irq_status_query irq_status;
 467         struct irq_info *info = info_for_irq(irq);
 468
 469         BUG_ON(info->type != IRQT_PIRQ);
 470
 471         irq_status.irq = pirq_from_irq(irq);
 472         if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
 473                 irq_status.flags = 0;
 474
 475         info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
 476         if (irq_status.flags & XENIRQSTAT_needs_eoi)
 477                 info->u.pirq.flags |= PIRQ_NEEDS_EOI;
 478 }
 479
 480 static void eoi_pirq(struct irq_data *data)
 481 {
 482         int evtchn = evtchn_from_irq(data->irq);
 483         struct physdev_eoi eoi = { .irq = pirq_from_irq(data->irq) };
 484         int rc = 0;
 485
 486         irq_move_irq(data);
 487
 488         if (VALID_EVTCHN(evtchn))
 489                 clear_evtchn(evtchn);
 490
 491         if (pirq_needs_eoi(data->irq)) {
 492                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
 493                 WARN_ON(rc);
 494         }
 495 }
 496
 497 static void mask_ack_pirq(struct irq_data *data)
 498 {
 499         disable_dynirq(data);
 500         eoi_pirq(data);
 501 }
 502
 503 static unsigned int __startup_pirq(unsigned int irq)
 504 {
 505         struct evtchn_bind_pirq bind_pirq;
 506         struct irq_info *info = info_for_irq(irq);
 507         int evtchn = evtchn_from_irq(irq);
 508         int rc;
 509
 510         BUG_ON(info->type != IRQT_PIRQ);
 511
 512         if (VALID_EVTCHN(evtchn))
 513                 goto out;
 514
 515         bind_pirq.pirq = pirq_from_irq(irq);
 516         /* NB. We are happy to share unless we are probing. */
 517         bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
 518                                         BIND_PIRQ__WILL_SHARE : 0;
 519         rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
 520         if (rc != 0) {
 521                 pr_warn("Failed to obtain physical IRQ %d\n", irq);
 522                 return 0;
 523         }
 524         evtchn = bind_pirq.port;
 525
 526         pirq_query_unmask(irq);
 527
 528         rc = set_evtchn_to_irq(evtchn, irq);
 529         if (rc)
 530                 goto err;
 531
 532         info->evtchn = evtchn;
 533         bind_evtchn_to_cpu(evtchn, 0);
 534
 535         rc = xen_evtchn_port_setup(info);
 536         if (rc)
 537                 goto err;
 538
 539 out:
 540         unmask_evtchn(evtchn);
 541         eoi_pirq(irq_get_irq_data(irq));
 542
 543         return 0;
 544
 545 err:
 546         pr_err("irq%d: Failed to set port to irq mapping (%d)\n", irq, rc);
 547         xen_evtchn_close(evtchn);
 548         return 0;
 549 }
 550
 551 static unsigned int startup_pirq(struct irq_data *data)
 552 {
 553         return __startup_pirq(data->irq);
 554 }
 555
 556 static void shutdown_pirq(struct irq_data *data)
 557 {
 558         unsigned int irq = data->irq;
 559         struct irq_info *info = info_for_irq(irq);
 560         unsigned evtchn = evtchn_from_irq(irq);
 561
 562         BUG_ON(info->type != IRQT_PIRQ);
 563
 564         if (!VALID_EVTCHN(evtchn))
 565                 return;
 566
 567         mask_evtchn(evtchn);
 568         xen_evtchn_close(evtchn);
 569         xen_irq_info_cleanup(info);
 570 }
 571
 572 static void enable_pirq(struct irq_data *data)
 573 {
 574         startup_pirq(data);
 575 }
 576
 577 static void disable_pirq(struct irq_data *data)
 578 {
 579         disable_dynirq(data);
 580 }
 581
 582 int xen_irq_from_gsi(unsigned gsi)
 583 {
 584         struct irq_info *info;
 585
 586         list_for_each_entry(info, &xen_irq_list_head, list) {
 587                 if (info->type != IRQT_PIRQ)
 588                         continue;
 589
 590                 if (info->u.pirq.gsi == gsi)
 591                         return info->irq;
 592         }
 593
 594         return -1;
 595 }
 596 EXPORT_SYMBOL_GPL(xen_irq_from_gsi);
 597
 598 static void __unbind_from_irq(unsigned int irq)
 599 {
 600         int evtchn = evtchn_from_irq(irq);
 601         struct irq_info *info = irq_get_handler_data(irq);
 602
 603         if (info->refcnt > 0) {
 604                 info->refcnt--;
 605                 if (info->refcnt != 0)
 606                         return;
 607         }
 608
 609         if (VALID_EVTCHN(evtchn)) {
 610                 unsigned int cpu = cpu_from_irq(irq);
 611
 612                 xen_evtchn_close(evtchn);
 613
 614                 switch (type_from_irq(irq)) {
 615                 case IRQT_VIRQ:
 616                         per_cpu(virq_to_irq, cpu)[virq_from_irq(irq)] = -1;
 617                         break;
 618                 case IRQT_IPI:
 619                         per_cpu(ipi_to_irq, cpu)[ipi_from_irq(irq)] = -1;
 620                         break;
 621                 default:
 622                         break;
 623                 }
 624
 625                 xen_irq_info_cleanup(info);
 626         }
 627
 628         BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);
 629
 630         xen_free_irq(irq);
 631 }
 632
 633 /*
 634  * Do not make any assumptions regarding the relationship between the
 635  * IRQ number returned here and the Xen pirq argument.
 636  *
 637  * Note: We don't assign an event channel until the irq actually started
 638  * up.  Return an existing irq if we've already got one for the gsi.
 639  *
 640  * Shareable implies level triggered, not shareable implies edge
 641  * triggered here.
 642  */
 643 int xen_bind_pirq_gsi_to_irq(unsigned gsi,
 644                              unsigned pirq, int shareable, char *name)
 645 {
 646         int irq = -1;
 647         struct physdev_irq irq_op;
 648         int ret;
 649
 650         mutex_lock(&irq_mapping_update_lock);
 651
 652         irq = xen_irq_from_gsi(gsi);
 653         if (irq != -1) {
 654                 pr_info("%s: returning irq %d for gsi %u\n",
 655                         __func__, irq, gsi);
 656                 goto out;
 657         }
 658
 659         irq = xen_allocate_irq_gsi(gsi);
 660         if (irq < 0)
 661                 goto out;
 662
 663         irq_op.irq = irq;
 664         irq_op.vector = 0;
 665
 666         /* Only the privileged domain can do this. For non-priv, the pcifront
 667          * driver provides a PCI bus that does the call to do exactly
 668          * this in the priv domain. */
 669         if (xen_initial_domain() &&
 670             HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
 671                 xen_free_irq(irq);
 672                 irq = -ENOSPC;
 673                 goto out;
 674         }
 675
 676         ret = xen_irq_info_pirq_setup(irq, 0, pirq, gsi, DOMID_SELF,
 677                                shareable ? PIRQ_SHAREABLE : 0);
 678         if (ret < 0) {
 679                 __unbind_from_irq(irq);
 680                 irq = ret;
 681                 goto out;
 682         }
 683
 684         pirq_query_unmask(irq);
 685         /* We try to use the handler with the appropriate semantic for the
 686          * type of interrupt: if the interrupt is an edge triggered
 687          * interrupt we use handle_edge_irq.
 688          *
 689          * On the other hand if the interrupt is level triggered we use
 690          * handle_fasteoi_irq like the native code does for this kind of
 691          * interrupts.
 692          *
 693          * Depending on the Xen version, pirq_needs_eoi might return true
 694          * not only for level triggered interrupts but for edge triggered
 695          * interrupts too. In any case Xen always honors the eoi mechanism,
 696          * not injecting any more pirqs of the same kind if the first one
 697          * hasn't received an eoi yet. Therefore using the fasteoi handler
 698          * is the right choice either way.
 699          */
 700         if (shareable)
 701                 irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
 702                                 handle_fasteoi_irq, name);
 703         else
 704                 irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
 705                                 handle_edge_irq, name);
 706
 707 out:
 708         mutex_unlock(&irq_mapping_update_lock);
 709
 710         return irq;
 711 }
 712
 713 #ifdef CONFIG_PCI_MSI
 714 int xen_allocate_pirq_msi(struct pci_dev *dev, struct msi_desc *msidesc)
 715 {
 716         int rc;
 717         struct physdev_get_free_pirq op_get_free_pirq;
 718
 719         op_get_free_pirq.type = MAP_PIRQ_TYPE_MSI;
 720         rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);
 721
 722         WARN_ONCE(rc == -ENOSYS,
 723                   "hypervisor does not support the PHYSDEVOP_get_free_pirq interface\n");
 724
 725         return rc ? -1 : op_get_free_pirq.pirq;
 726 }
 727
 728 int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
 729                              int pirq, int nvec, const char *name, domid_t domid)
 730 {
 731         int i, irq, ret;
 732
 733         mutex_lock(&irq_mapping_update_lock);
 734
 735         irq = xen_allocate_irqs_dynamic(nvec);
 736         if (irq < 0)
 737                 goto out;
 738
 739         for (i = 0; i < nvec; i++) {
 740                 irq_set_chip_and_handler_name(irq + i, &xen_pirq_chip, handle_edge_irq, name);
 741
 742                 ret = xen_irq_info_pirq_setup(irq + i, 0, pirq + i, 0, domid,
 743                                               i == 0 ? 0 : PIRQ_MSI_GROUP);
 744                 if (ret < 0)
 745                         goto error_irq;
 746         }
 747
 748         ret = irq_set_msi_desc(irq, msidesc);
 749         if (ret < 0)
 750                 goto error_irq;
 751 out:
 752         mutex_unlock(&irq_mapping_update_lock);
 753         return irq;
 754 error_irq:
 755         for (; i >= 0; i--)
 756                 __unbind_from_irq(irq + i);
 757         mutex_unlock(&irq_mapping_update_lock);
 758         return ret;
 759 }
 760 #endif
 761
 762 int xen_destroy_irq(int irq)
 763 {
 764         struct physdev_unmap_pirq unmap_irq;
 765         struct irq_info *info = info_for_irq(irq);
 766         int rc = -ENOENT;
 767
 768         mutex_lock(&irq_mapping_update_lock);
 769
 770         /*
 771          * If trying to remove a vector in a MSI group different
 772          * than the first one skip the PIRQ unmap unless this vector
 773          * is the first one in the group.
 774          */
 775         if (xen_initial_domain() && !(info->u.pirq.flags & PIRQ_MSI_GROUP)) {
 776                 unmap_irq.pirq = info->u.pirq.pirq;
 777                 unmap_irq.domid = info->u.pirq.domid;
 778                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
 779                 /* If another domain quits without making the pci_disable_msix
 780                  * call, the Xen hypervisor takes care of freeing the PIRQs
 781                  * (free_domain_pirqs).
 782                  */
 783                 if ((rc == -ESRCH && info->u.pirq.domid != DOMID_SELF))
 784                         pr_info("domain %d does not have %d anymore\n",
 785                                 info->u.pirq.domid, info->u.pirq.pirq);
 786                 else if (rc) {
 787                         pr_warn("unmap irq failed %d\n", rc);
 788                         goto out;
 789                 }
 790         }
 791
 792         xen_free_irq(irq);
 793
 794 out:
 795         mutex_unlock(&irq_mapping_update_lock);
 796         return rc;
 797 }
 798
 799 int xen_irq_from_pirq(unsigned pirq)
 800 {
 801         int irq;
 802
 803         struct irq_info *info;
 804
 805         mutex_lock(&irq_mapping_update_lock);
 806
 807         list_for_each_entry(info, &xen_irq_list_head, list) {
 808                 if (info->type != IRQT_PIRQ)
 809                         continue;
 810                 irq = info->irq;
 811                 if (info->u.pirq.pirq == pirq)
 812                         goto out;
 813         }
 814         irq = -1;
 815 out:
 816         mutex_unlock(&irq_mapping_update_lock);
 817
 818         return irq;
 819 }
 820
 821
 822 int xen_pirq_from_irq(unsigned irq)
 823 {
 824         return pirq_from_irq(irq);
 825 }
 826 EXPORT_SYMBOL_GPL(xen_pirq_from_irq);
 827
 828 int bind_evtchn_to_irq(unsigned int evtchn)
 829 {
 830         int irq;
 831         int ret;
 832
 833         if (evtchn >= xen_evtchn_max_channels())
 834                 return -ENOMEM;
 835
 836         mutex_lock(&irq_mapping_update_lock);
 837
 838         irq = get_evtchn_to_irq(evtchn);
 839
 840         if (irq == -1) {
 841                 irq = xen_allocate_irq_dynamic();
 842                 if (irq < 0)
 843                         goto out;
 844
 845                 irq_set_chip_and_handler_name(irq, &xen_dynamic_chip,
 846                                               handle_edge_irq, "event");
 847
 848                 ret = xen_irq_info_evtchn_setup(irq, evtchn);
 849                 if (ret < 0) {
 850                         __unbind_from_irq(irq);
 851                         irq = ret;
 852                         goto out;
 853                 }
 854                 /* New interdomain events are bound to VCPU 0. */
 855                 bind_evtchn_to_cpu(evtchn, 0);
 856         } else {
 857                 struct irq_info *info = info_for_irq(irq);
 858                 WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
 859         }
 860
 861 out:
 862         mutex_unlock(&irq_mapping_update_lock);
 863
 864         return irq;
 865 }
 866 EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
 867
 868 static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
 869 {
 870         struct evtchn_bind_ipi bind_ipi;
 871         int evtchn, irq;
 872         int ret;
 873
 874         mutex_lock(&irq_mapping_update_lock);
 875
 876         irq = per_cpu(ipi_to_irq, cpu)[ipi];
 877
 878         if (irq == -1) {
 879                 irq = xen_allocate_irq_dynamic();
 880                 if (irq < 0)
 881                         goto out;
 882
 883                 irq_set_chip_and_handler_name(irq, &xen_percpu_chip,
 884                                               handle_percpu_irq, "ipi");
 885
 886                 bind_ipi.vcpu = cpu;
 887                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
 888                                                 &bind_ipi) != 0)
 889                         BUG();
 890                 evtchn = bind_ipi.port;
 891
 892                 ret = xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi);
 893                 if (ret < 0) {
 894                         __unbind_from_irq(irq);
 895                         irq = ret;
 896                         goto out;
 897                 }
 898                 bind_evtchn_to_cpu(evtchn, cpu);
 899         } else {
 900                 struct irq_info *info = info_for_irq(irq);
 901                 WARN_ON(info == NULL || info->type != IRQT_IPI);
 902         }
 903
 904  out:
 905         mutex_unlock(&irq_mapping_update_lock);
 906         return irq;
 907 }
 908
 909 int bind_interdomain_evtchn_to_irq(unsigned int remote_domain,
 910                                    unsigned int remote_port)
 911 {
 912         struct evtchn_bind_interdomain bind_interdomain;
 913         int err;
 914
 915         bind_interdomain.remote_dom  = remote_domain;
 916         bind_interdomain.remote_port = remote_port;
 917
 918         err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain,
 919                                           &bind_interdomain);
 920
 921         return err ? : bind_evtchn_to_irq(bind_interdomain.local_port);
 922 }
 923 EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irq);
 924
 925 static int find_virq(unsigned int virq, unsigned int cpu)
 926 {
 927         struct evtchn_status status;
 928         int port, rc = -ENOENT;
 929
 930         memset(&status, 0, sizeof(status));
 931         for (port = 0; port < xen_evtchn_max_channels(); port++) {
 932                 status.dom = DOMID_SELF;
 933                 status.port = port;
 934                 rc = HYPERVISOR_event_channel_op(EVTCHNOP_status, &status);
 935                 if (rc < 0)
 936                         continue;
 937                 if (status.status != EVTCHNSTAT_virq)
 938                         continue;
 939                 if (status.u.virq == virq && status.vcpu == cpu) {
 940                         rc = port;
 941                         break;
 942                 }
 943         }
 944         return rc;
 945 }
 946
 947 /**
 948  * xen_evtchn_nr_channels - number of usable event channel ports
 949  *
 950  * This may be less than the maximum supported by the current
 951  * hypervisor ABI. Use xen_evtchn_max_channels() for the maximum
 952  * supported.
 953  */
 954 unsigned xen_evtchn_nr_channels(void)
 955 {
 956         return evtchn_ops->nr_channels();
 957 }
 958 EXPORT_SYMBOL_GPL(xen_evtchn_nr_channels);
 959
 960 int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
 961 {
 962         struct evtchn_bind_virq bind_virq;
 963         int evtchn, irq, ret;
 964
 965         mutex_lock(&irq_mapping_update_lock);
 966
 967         irq = per_cpu(virq_to_irq, cpu)[virq];
 968
 969         if (irq == -1) {
 970                 irq = xen_allocate_irq_dynamic();
 971                 if (irq < 0)
 972                         goto out;
 973
 974                 irq_set_chip_and_handler_name(irq, &xen_percpu_chip,
 975                                               handle_percpu_irq, "virq");
 976
 977                 bind_virq.virq = virq;
 978                 bind_virq.vcpu = cpu;
 979                 ret = HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
 980                                                 &bind_virq);
 981                 if (ret == 0)
 982                         evtchn = bind_virq.port;
 983                 else {
 984                         if (ret == -EEXIST)
 985                                 ret = find_virq(virq, cpu);
 986                         BUG_ON(ret < 0);
 987                         evtchn = ret;
 988                 }
 989
 990                 ret = xen_irq_info_virq_setup(cpu, irq, evtchn, virq);
 991                 if (ret < 0) {
 992                         __unbind_from_irq(irq);
 993                         irq = ret;
 994                         goto out;
 995                 }
 996
 997                 bind_evtchn_to_cpu(evtchn, cpu);
 998         } else {
 999                 struct irq_info *info = info_for_irq(irq);
1000                 WARN_ON(info == NULL || info->type != IRQT_VIRQ);
1001         }
1002
1003 out:
1004         mutex_unlock(&irq_mapping_update_lock);
1005
1006         return irq;
1007 }
1008
1009 static void unbind_from_irq(unsigned int irq)
1010 {
1011         mutex_lock(&irq_mapping_update_lock);
1012         __unbind_from_irq(irq);
1013         mutex_unlock(&irq_mapping_update_lock);
1014 }
1015
1016 int bind_evtchn_to_irqhandler(unsigned int evtchn,
1017                               irq_handler_t handler,
1018                               unsigned long irqflags,
1019                               const char *devname, void *dev_id)
1020 {
1021         int irq, retval;
1022
1023         irq = bind_evtchn_to_irq(evtchn);
1024         if (irq < 0)
1025                 return irq;
1026         retval = request_irq(irq, handler, irqflags, devname, dev_id);
1027         if (retval != 0) {
1028                 unbind_from_irq(irq);
1029                 return retval;
1030         }
1031
1032         return irq;
1033 }
1034 EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler);
1035
1036 int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain,
1037                                           unsigned int remote_port,
1038                                           irq_handler_t handler,
1039                                           unsigned long irqflags,
1040                                           const char *devname,
1041                                           void *dev_id)
1042 {
1043         int irq, retval;
1044
1045         irq = bind_interdomain_evtchn_to_irq(remote_domain, remote_port);
1046         if (irq < 0)
1047                 return irq;
1048
1049         retval = request_irq(irq, handler, irqflags, devname, dev_id);
1050         if (retval != 0) {
1051                 unbind_from_irq(irq);
1052                 return retval;
1053         }
1054
1055         return irq;
1056 }
1057 EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irqhandler);
1058
1059 int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
1060                             irq_handler_t handler,
1061                             unsigned long irqflags, const char *devname, void *dev_id)
1062 {
1063         int irq, retval;
1064
1065         irq = bind_virq_to_irq(virq, cpu);
1066         if (irq < 0)
1067                 return irq;
1068         retval = request_irq(irq, handler, irqflags, devname, dev_id);
1069         if (retval != 0) {
1070                 unbind_from_irq(irq);
1071                 return retval;
1072         }
1073
1074         return irq;
1075 }
1076 EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);
1077
1078 int bind_ipi_to_irqhandler(enum ipi_vector ipi,
1079                            unsigned int cpu,
1080                            irq_handler_t handler,
1081                            unsigned long irqflags,
1082                            const char *devname,
1083                            void *dev_id)
1084 {
1085         int irq, retval;
1086
1087         irq = bind_ipi_to_irq(ipi, cpu);
1088         if (irq < 0)
1089                 return irq;
1090
1091         irqflags |= IRQF_NO_SUSPEND | IRQF_FORCE_RESUME | IRQF_EARLY_RESUME;
1092         retval = request_irq(irq, handler, irqflags, devname, dev_id);
1093         if (retval != 0) {
1094                 unbind_from_irq(irq);
1095                 return retval;
1096         }
1097
1098         return irq;
1099 }
1100
1101 void unbind_from_irqhandler(unsigned int irq, void *dev_id)
1102 {
1103         struct irq_info *info = irq_get_handler_data(irq);
1104
1105         if (WARN_ON(!info))
1106                 return;
1107         free_irq(irq, dev_id);
1108         unbind_from_irq(irq);
1109 }
1110 EXPORT_SYMBOL_GPL(unbind_from_irqhandler);
1111
1112 /**
1113  * xen_set_irq_priority() - set an event channel priority.
1114  * @irq:irq bound to an event channel.
1115  * @priority: priority between XEN_IRQ_PRIORITY_MAX and XEN_IRQ_PRIORITY_MIN.
1116  */
1117 int xen_set_irq_priority(unsigned irq, unsigned priority)
1118 {
1119         struct evtchn_set_priority set_priority;
1120
1121         set_priority.port = evtchn_from_irq(irq);
1122         set_priority.priority = priority;
1123
1124         return HYPERVISOR_event_channel_op(EVTCHNOP_set_priority,
1125                                            &set_priority);
1126 }
1127 EXPORT_SYMBOL_GPL(xen_set_irq_priority);
1128
1129 int evtchn_make_refcounted(unsigned int evtchn)
1130 {
1131         int irq = get_evtchn_to_irq(evtchn);
1132         struct irq_info *info;
1133
1134         if (irq == -1)
1135                 return -ENOENT;
1136
1137         info = irq_get_handler_data(irq);
1138
1139         if (!info)
1140                 return -ENOENT;
1141
1142         WARN_ON(info->refcnt != -1);
1143
1144         info->refcnt = 1;
1145
1146         return 0;
1147 }
1148 EXPORT_SYMBOL_GPL(evtchn_make_refcounted);
1149
1150 int evtchn_get(unsigned int evtchn)
1151 {
1152         int irq;
1153         struct irq_info *info;
1154         int err = -ENOENT;
1155
1156         if (evtchn >= xen_evtchn_max_channels())
1157                 return -EINVAL;
1158
1159         mutex_lock(&irq_mapping_update_lock);
1160
1161         irq = get_evtchn_to_irq(evtchn);
1162         if (irq == -1)
1163                 goto done;
1164
1165         info = irq_get_handler_data(irq);
1166
1167         if (!info)
1168                 goto done;
1169
1170         err = -EINVAL;
1171         if (info->refcnt <= 0)
1172                 goto done;
1173
1174         info->refcnt++;
1175         err = 0;
1176  done:
1177         mutex_unlock(&irq_mapping_update_lock);
1178
1179         return err;
1180 }
1181 EXPORT_SYMBOL_GPL(evtchn_get);
1182
1183 void evtchn_put(unsigned int evtchn)
1184 {
1185         int irq = get_evtchn_to_irq(evtchn);
1186         if (WARN_ON(irq == -1))
1187                 return;
1188         unbind_from_irq(irq);
1189 }
1190 EXPORT_SYMBOL_GPL(evtchn_put);
1191
1192 void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
1193 {
1194         int irq;
1195
1196 #ifdef CONFIG_X86
1197         if (unlikely(vector == XEN_NMI_VECTOR)) {
1198                 int rc =  HYPERVISOR_vcpu_op(VCPUOP_send_nmi, cpu, NULL);
1199                 if (rc < 0)
1200                         printk(KERN_WARNING "Sending nmi to CPU%d failed (rc:%d)\n", cpu, rc);
1201                 return;
1202         }
1203 #endif
1204         irq = per_cpu(ipi_to_irq, cpu)[vector];
1205         BUG_ON(irq < 0);
1206         notify_remote_via_irq(irq);
1207 }
1208
1209 static DEFINE_PER_CPU(unsigned, xed_nesting_count);
1210
1211 static void __xen_evtchn_do_upcall(void)
1212 {
1213         struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
1214         int cpu = get_cpu();
1215         unsigned count;
1216
1217         do {
1218                 vcpu_info->evtchn_upcall_pending = 0;
1219
1220                 if (__this_cpu_inc_return(xed_nesting_count) - 1)
1221                         goto out;
1222
1223                 xen_evtchn_handle_events(cpu);
1224
1225                 BUG_ON(!irqs_disabled());
1226
1227                 count = __this_cpu_read(xed_nesting_count);
1228                 __this_cpu_write(xed_nesting_count, 0);
1229         } while (count != 1 || vcpu_info->evtchn_upcall_pending);
1230
1231 out:
1232
1233         put_cpu();
1234 }
1235
1236 void xen_evtchn_do_upcall(struct pt_regs *regs)
1237 {
1238         struct pt_regs *old_regs = set_irq_regs(regs);
1239
1240         irq_enter();
1241 #ifdef CONFIG_X86
1242         exit_idle();
1243         inc_irq_stat(irq_hv_callback_count);
1244 #endif
1245
1246         __xen_evtchn_do_upcall();
1247
1248         irq_exit();
1249         set_irq_regs(old_regs);
1250 }
1251
1252 void xen_hvm_evtchn_do_upcall(void)
1253 {
1254         __xen_evtchn_do_upcall();
1255 }
1256 EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall);
1257
1258 /* Rebind a new event channel to an existing irq. */
1259 void rebind_evtchn_irq(int evtchn, int irq)
1260 {
1261         struct irq_info *info = info_for_irq(irq);
1262
1263         if (WARN_ON(!info))
1264                 return;
1265
1266         /* Make sure the irq is masked, since the new event channel
1267            will also be masked. */
1268         disable_irq(irq);
1269
1270         mutex_lock(&irq_mapping_update_lock);
1271
1272         /* After resume the irq<->evtchn mappings are all cleared out */
1273         BUG_ON(get_evtchn_to_irq(evtchn) != -1);
1274         /* Expect irq to have been bound before,
1275            so there should be a proper type */
1276         BUG_ON(info->type == IRQT_UNBOUND);
1277
1278         (void)xen_irq_info_evtchn_setup(irq, evtchn);
1279
1280         mutex_unlock(&irq_mapping_update_lock);
1281
1282         bind_evtchn_to_cpu(evtchn, info->cpu);
1283         /* This will be deferred until interrupt is processed */
1284         irq_set_affinity(irq, cpumask_of(info->cpu));
1285
1286         /* Unmask the event channel. */
1287         enable_irq(irq);
1288 }
1289
1290 /* Rebind an evtchn so that it gets delivered to a specific cpu */
1291 static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
1292 {
1293         struct evtchn_bind_vcpu bind_vcpu;
1294         int evtchn = evtchn_from_irq(irq);
1295         int masked;
1296
1297         if (!VALID_EVTCHN(evtchn))
1298                 return -1;
1299
1300         /*
1301          * Events delivered via platform PCI interrupts are always
1302          * routed to vcpu 0 and hence cannot be rebound.
1303          */
1304         if (xen_hvm_domain() && !xen_have_vector_callback)
1305                 return -1;
1306
1307         /* Send future instances of this interrupt to other vcpu. */
1308         bind_vcpu.port = evtchn;
1309         bind_vcpu.vcpu = tcpu;
1310
1311         /*
1312          * Mask the event while changing the VCPU binding to prevent
1313          * it being delivered on an unexpected VCPU.
1314          */
1315         masked = test_and_set_mask(evtchn);
1316
1317         /*
1318          * If this fails, it usually just indicates that we're dealing with a
1319          * virq or IPI channel, which don't actually need to be rebound. Ignore
1320          * it, but don't do the xenlinux-level rebind in that case.
1321          */
1322         if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
1323                 bind_evtchn_to_cpu(evtchn, tcpu);
1324
1325         if (!masked)
1326                 unmask_evtchn(evtchn);
1327
1328         return 0;
1329 }
1330
1331 static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest,
1332                             bool force)
1333 {
1334         unsigned tcpu = cpumask_first_and(dest, cpu_online_mask);
1335
1336         return rebind_irq_to_cpu(data->irq, tcpu);
1337 }
1338
1339 static void enable_dynirq(struct irq_data *data)
1340 {
1341         int evtchn = evtchn_from_irq(data->irq);
1342
1343         if (VALID_EVTCHN(evtchn))
1344                 unmask_evtchn(evtchn);
1345 }
1346
1347 static void disable_dynirq(struct irq_data *data)
1348 {
1349         int evtchn = evtchn_from_irq(data->irq);
1350
1351         if (VALID_EVTCHN(evtchn))
1352                 mask_evtchn(evtchn);
1353 }
1354
1355 static void ack_dynirq(struct irq_data *data)
1356 {
1357         int evtchn = evtchn_from_irq(data->irq);
1358
1359         irq_move_irq(data);
1360
1361         if (VALID_EVTCHN(evtchn))
1362                 clear_evtchn(evtchn);
1363 }
1364
1365 static void mask_ack_dynirq(struct irq_data *data)
1366 {
1367         disable_dynirq(data);
1368         ack_dynirq(data);
1369 }
1370
1371 static int retrigger_dynirq(struct irq_data *data)
1372 {
1373         unsigned int evtchn = evtchn_from_irq(data->irq);
1374         int masked;
1375
1376         if (!VALID_EVTCHN(evtchn))
1377                 return 0;
1378
1379         masked = test_and_set_mask(evtchn);
1380         set_evtchn(evtchn);
1381         if (!masked)
1382                 unmask_evtchn(evtchn);
1383
1384         return 1;
1385 }
1386
1387 static void restore_pirqs(void)
1388 {
1389         int pirq, rc, irq, gsi;
1390         struct physdev_map_pirq map_irq;
1391         struct irq_info *info;
1392
1393         list_for_each_entry(info, &xen_irq_list_head, list) {
1394                 if (info->type != IRQT_PIRQ)
1395                         continue;
1396
1397                 pirq = info->u.pirq.pirq;
1398                 gsi = info->u.pirq.gsi;
1399                 irq = info->irq;
1400
1401                 /* save/restore of PT devices doesn't work, so at this point the
1402                  * only devices present are GSI based emulated devices */
1403                 if (!gsi)
1404                         continue;
1405
1406                 map_irq.domid = DOMID_SELF;
1407                 map_irq.type = MAP_PIRQ_TYPE_GSI;
1408                 map_irq.index = gsi;
1409                 map_irq.pirq = pirq;
1410
1411                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
1412                 if (rc) {
1413                         pr_warn("xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
1414                                 gsi, irq, pirq, rc);
1415                         xen_free_irq(irq);
1416                         continue;
1417                 }
1418
1419                 printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
1420
1421                 __startup_pirq(irq);
1422         }
1423 }
1424
1425 static void restore_cpu_virqs(unsigned int cpu)
1426 {
1427         struct evtchn_bind_virq bind_virq;
1428         int virq, irq, evtchn;
1429
1430         for (virq = 0; virq < NR_VIRQS; virq++) {
1431                 if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1)
1432                         continue;
1433
1434                 BUG_ON(virq_from_irq(irq) != virq);
1435
1436                 /* Get a new binding from Xen. */
1437                 bind_virq.virq = virq;
1438                 bind_virq.vcpu = cpu;
1439                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
1440                                                 &bind_virq) != 0)
1441                         BUG();
1442                 evtchn = bind_virq.port;
1443
1444                 /* Record the new mapping. */
1445                 (void)xen_irq_info_virq_setup(cpu, irq, evtchn, virq);
1446                 bind_evtchn_to_cpu(evtchn, cpu);
1447         }
1448 }
1449
1450 static void restore_cpu_ipis(unsigned int cpu)
1451 {
1452         struct evtchn_bind_ipi bind_ipi;
1453         int ipi, irq, evtchn;
1454
1455         for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) {
1456                 if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1)
1457                         continue;
1458
1459                 BUG_ON(ipi_from_irq(irq) != ipi);
1460
1461                 /* Get a new binding from Xen. */
1462                 bind_ipi.vcpu = cpu;
1463                 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
1464                                                 &bind_ipi) != 0)
1465                         BUG();
1466                 evtchn = bind_ipi.port;
1467
1468                 /* Record the new mapping. */
1469                 (void)xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi);
1470                 bind_evtchn_to_cpu(evtchn, cpu);
1471         }
1472 }
1473
1474 /* Clear an irq's pending state, in preparation for polling on it */
1475 void xen_clear_irq_pending(int irq)
1476 {
1477         int evtchn = evtchn_from_irq(irq);
1478
1479         if (VALID_EVTCHN(evtchn))
1480                 clear_evtchn(evtchn);
1481 }
1482 EXPORT_SYMBOL(xen_clear_irq_pending);
1483 void xen_set_irq_pending(int irq)
1484 {
1485         int evtchn = evtchn_from_irq(irq);
1486
1487         if (VALID_EVTCHN(evtchn))
1488                 set_evtchn(evtchn);
1489 }
1490
1491 bool xen_test_irq_pending(int irq)
1492 {
1493         int evtchn = evtchn_from_irq(irq);
1494         bool ret = false;
1495
1496         if (VALID_EVTCHN(evtchn))
1497                 ret = test_evtchn(evtchn);
1498
1499         return ret;
1500 }
1501
1502 /* Poll waiting for an irq to become pending with timeout.  In the usual case,
1503  * the irq will be disabled so it won't deliver an interrupt. */
1504 void xen_poll_irq_timeout(int irq, u64 timeout)
1505 {
1506         evtchn_port_t evtchn = evtchn_from_irq(irq);
1507
1508         if (VALID_EVTCHN(evtchn)) {
1509                 struct sched_poll poll;
1510
1511                 poll.nr_ports = 1;
1512                 poll.timeout = timeout;
1513                 set_xen_guest_handle(poll.ports, &evtchn);
1514
1515                 if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
1516                         BUG();
1517         }
1518 }
1519 EXPORT_SYMBOL(xen_poll_irq_timeout);
1520 /* Poll waiting for an irq to become pending.  In the usual case, the
1521  * irq will be disabled so it won't deliver an interrupt. */
1522 void xen_poll_irq(int irq)
1523 {
1524         xen_poll_irq_timeout(irq, 0 /* no timeout */);
1525 }
1526
1527 /* Check whether the IRQ line is shared with other guests. */
1528 int xen_test_irq_shared(int irq)
1529 {
1530         struct irq_info *info = info_for_irq(irq);
1531         struct physdev_irq_status_query irq_status;
1532
1533         if (WARN_ON(!info))
1534                 return -ENOENT;
1535
1536         irq_status.irq = info->u.pirq.pirq;
1537
1538         if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
1539                 return 0;
1540         return !(irq_status.flags & XENIRQSTAT_shared);
1541 }
1542 EXPORT_SYMBOL_GPL(xen_test_irq_shared);
1543
1544 void xen_irq_resume(void)
1545 {
1546         unsigned int cpu;
1547         struct irq_info *info;
1548
1549         /* New event-channel space is not 'live' yet. */
1550         xen_evtchn_mask_all();
1551         xen_evtchn_resume();
1552
1553         /* No IRQ <-> event-channel mappings. */
1554         list_for_each_entry(info, &xen_irq_list_head, list)
1555                 info->evtchn = 0; /* zap event-channel binding */
1556
1557         clear_evtchn_to_irq_all();
1558
1559         for_each_possible_cpu(cpu) {
1560                 restore_cpu_virqs(cpu);
1561                 restore_cpu_ipis(cpu);
1562         }
1563
1564         restore_pirqs();
1565 }
1566
1567 static struct irq_chip xen_dynamic_chip __read_mostly = {
1568         .name                   = "xen-dyn",
1569
1570         .irq_disable            = disable_dynirq,
1571         .irq_mask               = disable_dynirq,
1572         .irq_unmask             = enable_dynirq,
1573
1574         .irq_ack                = ack_dynirq,
1575         .irq_mask_ack           = mask_ack_dynirq,
1576
1577         .irq_set_affinity       = set_affinity_irq,
1578         .irq_retrigger          = retrigger_dynirq,
1579 };
1580
1581 static struct irq_chip xen_pirq_chip __read_mostly = {
1582         .name                   = "xen-pirq",
1583
1584         .irq_startup            = startup_pirq,
1585         .irq_shutdown           = shutdown_pirq,
1586         .irq_enable             = enable_pirq,
1587         .irq_disable            = disable_pirq,
1588
1589         .irq_mask               = disable_dynirq,
1590         .irq_unmask             = enable_dynirq,
1591
1592         .irq_ack                = eoi_pirq,
1593         .irq_eoi                = eoi_pirq,
1594         .irq_mask_ack           = mask_ack_pirq,
1595
1596         .irq_set_affinity       = set_affinity_irq,
1597
1598         .irq_retrigger          = retrigger_dynirq,
1599 };
1600
1601 static struct irq_chip xen_percpu_chip __read_mostly = {
1602         .name                   = "xen-percpu",
1603
1604         .irq_disable            = disable_dynirq,
1605         .irq_mask               = disable_dynirq,
1606         .irq_unmask             = enable_dynirq,
1607
1608         .irq_ack                = ack_dynirq,
1609 };
1610
1611 int xen_set_callback_via(uint64_t via)
1612 {
1613         struct xen_hvm_param a;
1614         a.domid = DOMID_SELF;
1615         a.index = HVM_PARAM_CALLBACK_IRQ;
1616         a.value = via;
1617         return HYPERVISOR_hvm_op(HVMOP_set_param, &a);
1618 }
1619 EXPORT_SYMBOL_GPL(xen_set_callback_via);
1620
1621 #ifdef CONFIG_XEN_PVHVM
1622 /* Vector callbacks are better than PCI interrupts to receive event
1623  * channel notifications because we can receive vector callbacks on any
1624  * vcpu and we don't need PCI support or APIC interactions. */
1625 void xen_callback_vector(void)
1626 {
1627         int rc;
1628         uint64_t callback_via;
1629         if (xen_have_vector_callback) {
1630                 callback_via = HVM_CALLBACK_VECTOR(HYPERVISOR_CALLBACK_VECTOR);
1631                 rc = xen_set_callback_via(callback_via);
1632                 if (rc) {
1633                         pr_err("Request for Xen HVM callback vector failed\n");
1634                         xen_have_vector_callback = 0;
1635                         return;
1636                 }
1637                 pr_info("Xen HVM callback vector for event delivery is enabled\n");
1638                 /* in the restore case the vector has already been allocated */
1639                 if (!test_bit(HYPERVISOR_CALLBACK_VECTOR, used_vectors))
1640                         alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR,
1641                                         xen_hvm_callback_vector);
1642         }
1643 }
1644 #else
1645 void xen_callback_vector(void) {}
1646 #endif
1647
1648 #undef MODULE_PARAM_PREFIX
1649 #define MODULE_PARAM_PREFIX "xen."
1650
1651 static bool fifo_events = true;
1652 module_param(fifo_events, bool, 0);
1653
1654 void __init xen_init_IRQ(void)
1655 {
1656         int ret = -EINVAL;
1657
1658         if (fifo_events)
1659                 ret = xen_evtchn_fifo_init();
1660         if (ret < 0)
1661                 xen_evtchn_2l_init();
1662
1663         evtchn_to_irq = kcalloc(EVTCHN_ROW(xen_evtchn_max_channels()),
1664                                 sizeof(*evtchn_to_irq), GFP_KERNEL);
1665         BUG_ON(!evtchn_to_irq);
1666
1667         /* No event channels are 'live' right now. */
1668         xen_evtchn_mask_all();
1669
1670         pirq_needs_eoi = pirq_needs_eoi_flag;
1671
1672 #ifdef CONFIG_X86
1673         if (xen_pv_domain()) {
1674                 irq_ctx_init(smp_processor_id());
1675                 if (xen_initial_domain())
1676                         pci_xen_initial_domain();
1677         }
1678         if (xen_feature(XENFEAT_hvm_callback_vector))
1679                 xen_callback_vector();
1680
1681         if (xen_hvm_domain()) {
1682                 native_init_IRQ();
1683                 /* pci_xen_hvm_init must be called after native_init_IRQ so that
1684                  * __acpi_register_gsi can point at the right function */
1685                 pci_xen_hvm_init();
1686         } else {
1687                 int rc;
1688                 struct physdev_pirq_eoi_gmfn eoi_gmfn;
1689
1690                 pirq_eoi_map = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
1691                 eoi_gmfn.gmfn = virt_to_mfn(pirq_eoi_map);
1692                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_pirq_eoi_gmfn_v2, &eoi_gmfn);
1693                 /* TODO: No PVH support for PIRQ EOI */
1694                 if (rc != 0) {
1695                         free_page((unsigned long) pirq_eoi_map);
1696                         pirq_eoi_map = NULL;
1697                 } else
1698                         pirq_needs_eoi = pirq_check_eoi_map;
1699         }
1700 #endif
1701 }