kernel/irq/irqdesc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
   4  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
   5  *
   6  * This file contains the interrupt descriptor management code. Detailed
   7  * information is available in Documentation/core-api/genericirq.rst
   8  *
   9  */
  10 #include <linux/irq.h>
  11 #include <linux/slab.h>
  12 #include <linux/export.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/kernel_stat.h>
  15 #include <linux/maple_tree.h>
  16 #include <linux/irqdomain.h>
  17 #include <linux/sysfs.h>
  18 #include <linux/string_choices.h>
  19
  20 #include "internals.h"
  21
  22 /*
  23  * lockdep: we want to handle all irq_desc locks as a single lock-class:
  24  */
  25 static struct lock_class_key irq_desc_lock_class;
  26
  27 #if defined(CONFIG_SMP)
  28 static int __init irq_affinity_setup(char *str)
  29 {
  30         alloc_bootmem_cpumask_var(&irq_default_affinity);
  31         cpulist_parse(str, irq_default_affinity);
  32         /*
  33          * Set at least the boot cpu. We don't want to end up with
  34          * bugreports caused by random commandline masks
  35          */
  36         cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
  37         return 1;
  38 }
  39 __setup("irqaffinity=", irq_affinity_setup);
  40
  41 static void __init init_irq_default_affinity(void)
  42 {
  43         if (!cpumask_available(irq_default_affinity))
  44                 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
  45         if (cpumask_empty(irq_default_affinity))
  46                 cpumask_setall(irq_default_affinity);
  47 }
  48 #else
  49 static void __init init_irq_default_affinity(void)
  50 {
  51 }
  52 #endif
  53
  54 #ifdef CONFIG_SMP
  55 static int alloc_masks(struct irq_desc *desc, int node)
  56 {
  57         if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
  58                                      GFP_KERNEL, node))
  59                 return -ENOMEM;
  60
  61 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
  62         if (!zalloc_cpumask_var_node(&desc->irq_common_data.effective_affinity,
  63                                      GFP_KERNEL, node)) {
  64                 free_cpumask_var(desc->irq_common_data.affinity);
  65                 return -ENOMEM;
  66         }
  67 #endif
  68
  69 #ifdef CONFIG_GENERIC_PENDING_IRQ
  70         if (!zalloc_cpumask_var_node(&desc->pending_mask, GFP_KERNEL, node)) {
  71 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
  72                 free_cpumask_var(desc->irq_common_data.effective_affinity);
  73 #endif
  74                 free_cpumask_var(desc->irq_common_data.affinity);
  75                 return -ENOMEM;
  76         }
  77 #endif
  78         return 0;
  79 }
  80
  81 static void desc_smp_init(struct irq_desc *desc, int node,
  82                           const struct cpumask *affinity)
  83 {
  84         if (!affinity)
  85                 affinity = irq_default_affinity;
  86         cpumask_copy(desc->irq_common_data.affinity, affinity);
  87
  88 #ifdef CONFIG_GENERIC_PENDING_IRQ
  89         cpumask_clear(desc->pending_mask);
  90 #endif
  91 #ifdef CONFIG_NUMA
  92         desc->irq_common_data.node = node;
  93 #endif
  94 }
  95
  96 static void free_masks(struct irq_desc *desc)
  97 {
  98 #ifdef CONFIG_GENERIC_PENDING_IRQ
  99         free_cpumask_var(desc->pending_mask);
 100 #endif
 101         free_cpumask_var(desc->irq_common_data.affinity);
 102 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
 103         free_cpumask_var(desc->irq_common_data.effective_affinity);
 104 #endif
 105 }
 106
 107 #else
 108 static inline int
 109 alloc_masks(struct irq_desc *desc, int node) { return 0; }
 110 static inline void
 111 desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
 112 static inline void free_masks(struct irq_desc *desc) { }
 113 #endif
 114
 115 static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
 116                               const struct cpumask *affinity, struct module *owner)
 117 {
 118         int cpu;
 119
 120         desc->irq_common_data.handler_data = NULL;
 121         desc->irq_common_data.msi_desc = NULL;
 122
 123         desc->irq_data.common = &desc->irq_common_data;
 124         desc->irq_data.irq = irq;
 125         desc->irq_data.chip = &no_irq_chip;
 126         desc->irq_data.chip_data = NULL;
 127         irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
 128         irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
 129         irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
 130         desc->handle_irq = handle_bad_irq;
 131         desc->depth = 1;
 132         desc->irq_count = 0;
 133         desc->irqs_unhandled = 0;
 134         desc->tot_count = 0;
 135         desc->name = NULL;
 136         desc->owner = owner;
 137         for_each_possible_cpu(cpu)
 138                 *per_cpu_ptr(desc->kstat_irqs, cpu) = (struct irqstat) { };
 139         desc_smp_init(desc, node, affinity);
 140 }
 141
 142 static unsigned int nr_irqs = NR_IRQS;
 143
 144 /**
 145  * irq_get_nr_irqs() - Number of interrupts supported by the system.
 146  */
 147 unsigned int irq_get_nr_irqs(void)
 148 {
 149         return nr_irqs;
 150 }
 151 EXPORT_SYMBOL_GPL(irq_get_nr_irqs);
 152
 153 /**
 154  * irq_set_nr_irqs() - Set the number of interrupts supported by the system.
 155  * @nr: New number of interrupts.
 156  *
 157  * Return: @nr.
 158  */
 159 unsigned int irq_set_nr_irqs(unsigned int nr)
 160 {
 161         nr_irqs = nr;
 162
 163         return nr;
 164 }
 165 EXPORT_SYMBOL_GPL(irq_set_nr_irqs);
 166
 167 static DEFINE_MUTEX(sparse_irq_lock);
 168 static struct maple_tree sparse_irqs = MTREE_INIT_EXT(sparse_irqs,
 169                                         MT_FLAGS_ALLOC_RANGE |
 170                                         MT_FLAGS_LOCK_EXTERN |
 171                                         MT_FLAGS_USE_RCU,
 172                                         sparse_irq_lock);
 173
 174 static int irq_find_free_area(unsigned int from, unsigned int cnt)
 175 {
 176         MA_STATE(mas, &sparse_irqs, 0, 0);
 177
 178         if (mas_empty_area(&mas, from, MAX_SPARSE_IRQS, cnt))
 179                 return -ENOSPC;
 180         return mas.index;
 181 }
 182
 183 static unsigned int irq_find_at_or_after(unsigned int offset)
 184 {
 185         unsigned long index = offset;
 186         struct irq_desc *desc;
 187
 188         guard(rcu)();
 189         desc = mt_find(&sparse_irqs, &index, nr_irqs);
 190
 191         return desc ? irq_desc_get_irq(desc) : nr_irqs;
 192 }
 193
 194 static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
 195 {
 196         MA_STATE(mas, &sparse_irqs, irq, irq);
 197         WARN_ON(mas_store_gfp(&mas, desc, GFP_KERNEL) != 0);
 198 }
 199
 200 static void delete_irq_desc(unsigned int irq)
 201 {
 202         MA_STATE(mas, &sparse_irqs, irq, irq);
 203         mas_erase(&mas);
 204 }
 205
 206 #ifdef CONFIG_SPARSE_IRQ
 207 static const struct kobj_type irq_kobj_type;
 208 #endif
 209
 210 static int init_desc(struct irq_desc *desc, int irq, int node,
 211                      unsigned int flags,
 212                      const struct cpumask *affinity,
 213                      struct module *owner)
 214 {
 215         desc->kstat_irqs = alloc_percpu(struct irqstat);
 216         if (!desc->kstat_irqs)
 217                 return -ENOMEM;
 218
 219         if (alloc_masks(desc, node)) {
 220                 free_percpu(desc->kstat_irqs);
 221                 return -ENOMEM;
 222         }
 223
 224         raw_spin_lock_init(&desc->lock);
 225         lockdep_set_class(&desc->lock, &irq_desc_lock_class);
 226         mutex_init(&desc->request_mutex);
 227         init_waitqueue_head(&desc->wait_for_threads);
 228         desc_set_defaults(irq, desc, node, affinity, owner);
 229         irqd_set(&desc->irq_data, flags);
 230         irq_resend_init(desc);
 231 #ifdef CONFIG_SPARSE_IRQ
 232         kobject_init(&desc->kobj, &irq_kobj_type);
 233         init_rcu_head(&desc->rcu);
 234 #endif
 235
 236         return 0;
 237 }
 238
 239 #ifdef CONFIG_SPARSE_IRQ
 240
 241 static void irq_kobj_release(struct kobject *kobj);
 242
 243 #ifdef CONFIG_SYSFS
 244 static struct kobject *irq_kobj_base;
 245
 246 #define IRQ_ATTR_RO(_name) \
 247 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 248
 249 static ssize_t per_cpu_count_show(struct kobject *kobj,
 250                                   struct kobj_attribute *attr, char *buf)
 251 {
 252         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 253         ssize_t ret = 0;
 254         char *p = "";
 255         int cpu;
 256
 257         for_each_possible_cpu(cpu) {
 258                 unsigned int c = irq_desc_kstat_cpu(desc, cpu);
 259
 260                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
 261                 p = ",";
 262         }
 263
 264         ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 265         return ret;
 266 }
 267 IRQ_ATTR_RO(per_cpu_count);
 268
 269 static ssize_t chip_name_show(struct kobject *kobj,
 270                               struct kobj_attribute *attr, char *buf)
 271 {
 272         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 273         ssize_t ret = 0;
 274
 275         raw_spin_lock_irq(&desc->lock);
 276         if (desc->irq_data.chip && desc->irq_data.chip->name) {
 277                 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
 278                                 desc->irq_data.chip->name);
 279         }
 280         raw_spin_unlock_irq(&desc->lock);
 281
 282         return ret;
 283 }
 284 IRQ_ATTR_RO(chip_name);
 285
 286 static ssize_t hwirq_show(struct kobject *kobj,
 287                           struct kobj_attribute *attr, char *buf)
 288 {
 289         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 290         ssize_t ret = 0;
 291
 292         raw_spin_lock_irq(&desc->lock);
 293         if (desc->irq_data.domain)
 294                 ret = sprintf(buf, "%lu\n", desc->irq_data.hwirq);
 295         raw_spin_unlock_irq(&desc->lock);
 296
 297         return ret;
 298 }
 299 IRQ_ATTR_RO(hwirq);
 300
 301 static ssize_t type_show(struct kobject *kobj,
 302                          struct kobj_attribute *attr, char *buf)
 303 {
 304         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 305         ssize_t ret = 0;
 306
 307         raw_spin_lock_irq(&desc->lock);
 308         ret = sprintf(buf, "%s\n",
 309                       irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
 310         raw_spin_unlock_irq(&desc->lock);
 311
 312         return ret;
 313
 314 }
 315 IRQ_ATTR_RO(type);
 316
 317 static ssize_t wakeup_show(struct kobject *kobj,
 318                            struct kobj_attribute *attr, char *buf)
 319 {
 320         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 321         ssize_t ret = 0;
 322
 323         raw_spin_lock_irq(&desc->lock);
 324         ret = sprintf(buf, "%s\n", str_enabled_disabled(irqd_is_wakeup_set(&desc->irq_data)));
 325         raw_spin_unlock_irq(&desc->lock);
 326
 327         return ret;
 328
 329 }
 330 IRQ_ATTR_RO(wakeup);
 331
 332 static ssize_t name_show(struct kobject *kobj,
 333                          struct kobj_attribute *attr, char *buf)
 334 {
 335         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 336         ssize_t ret = 0;
 337
 338         raw_spin_lock_irq(&desc->lock);
 339         if (desc->name)
 340                 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
 341         raw_spin_unlock_irq(&desc->lock);
 342
 343         return ret;
 344 }
 345 IRQ_ATTR_RO(name);
 346
 347 static ssize_t actions_show(struct kobject *kobj,
 348                             struct kobj_attribute *attr, char *buf)
 349 {
 350         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 351         struct irqaction *action;
 352         ssize_t ret = 0;
 353         char *p = "";
 354
 355         raw_spin_lock_irq(&desc->lock);
 356         for_each_action_of_desc(desc, action) {
 357                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
 358                                  p, action->name);
 359                 p = ",";
 360         }
 361         raw_spin_unlock_irq(&desc->lock);
 362
 363         if (ret)
 364                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 365
 366         return ret;
 367 }
 368 IRQ_ATTR_RO(actions);
 369
 370 static struct attribute *irq_attrs[] = {
 371         &per_cpu_count_attr.attr,
 372         &chip_name_attr.attr,
 373         &hwirq_attr.attr,
 374         &type_attr.attr,
 375         &wakeup_attr.attr,
 376         &name_attr.attr,
 377         &actions_attr.attr,
 378         NULL
 379 };
 380 ATTRIBUTE_GROUPS(irq);
 381
 382 static const struct kobj_type irq_kobj_type = {
 383         .release        = irq_kobj_release,
 384         .sysfs_ops      = &kobj_sysfs_ops,
 385         .default_groups = irq_groups,
 386 };
 387
 388 static void irq_sysfs_add(int irq, struct irq_desc *desc)
 389 {
 390         if (irq_kobj_base) {
 391                 /*
 392                  * Continue even in case of failure as this is nothing
 393                  * crucial and failures in the late irq_sysfs_init()
 394                  * cannot be rolled back.
 395                  */
 396                 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
 397                         pr_warn("Failed to add kobject for irq %d\n", irq);
 398                 else
 399                         desc->istate |= IRQS_SYSFS;
 400         }
 401 }
 402
 403 static void irq_sysfs_del(struct irq_desc *desc)
 404 {
 405         /*
 406          * Only invoke kobject_del() when kobject_add() was successfully
 407          * invoked for the descriptor. This covers both early boot, where
 408          * sysfs is not initialized yet, and the case of a failed
 409          * kobject_add() invocation.
 410          */
 411         if (desc->istate & IRQS_SYSFS)
 412                 kobject_del(&desc->kobj);
 413 }
 414
 415 static int __init irq_sysfs_init(void)
 416 {
 417         struct irq_desc *desc;
 418         int irq;
 419
 420         /* Prevent concurrent irq alloc/free */
 421         irq_lock_sparse();
 422
 423         irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
 424         if (!irq_kobj_base) {
 425                 irq_unlock_sparse();
 426                 return -ENOMEM;
 427         }
 428
 429         /* Add the already allocated interrupts */
 430         for_each_irq_desc(irq, desc)
 431                 irq_sysfs_add(irq, desc);
 432         irq_unlock_sparse();
 433
 434         return 0;
 435 }
 436 postcore_initcall(irq_sysfs_init);
 437
 438 #else /* !CONFIG_SYSFS */
 439
 440 static const struct kobj_type irq_kobj_type = {
 441         .release        = irq_kobj_release,
 442 };
 443
 444 static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
 445 static void irq_sysfs_del(struct irq_desc *desc) {}
 446
 447 #endif /* CONFIG_SYSFS */
 448
 449 struct irq_desc *irq_to_desc(unsigned int irq)
 450 {
 451         return mtree_load(&sparse_irqs, irq);
 452 }
 453 #ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
 454 EXPORT_SYMBOL_GPL(irq_to_desc);
 455 #endif
 456
 457 void irq_lock_sparse(void)
 458 {
 459         mutex_lock(&sparse_irq_lock);
 460 }
 461
 462 void irq_unlock_sparse(void)
 463 {
 464         mutex_unlock(&sparse_irq_lock);
 465 }
 466
 467 static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
 468                                    const struct cpumask *affinity,
 469                                    struct module *owner)
 470 {
 471         struct irq_desc *desc;
 472         int ret;
 473
 474         desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
 475         if (!desc)
 476                 return NULL;
 477
 478         ret = init_desc(desc, irq, node, flags, affinity, owner);
 479         if (unlikely(ret)) {
 480                 kfree(desc);
 481                 return NULL;
 482         }
 483
 484         return desc;
 485 }
 486
 487 static void irq_kobj_release(struct kobject *kobj)
 488 {
 489         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 490
 491         free_masks(desc);
 492         free_percpu(desc->kstat_irqs);
 493         kfree(desc);
 494 }
 495
 496 static void delayed_free_desc(struct rcu_head *rhp)
 497 {
 498         struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
 499
 500         kobject_put(&desc->kobj);
 501 }
 502
 503 static void free_desc(unsigned int irq)
 504 {
 505         struct irq_desc *desc = irq_to_desc(irq);
 506
 507         irq_remove_debugfs_entry(desc);
 508         unregister_irq_proc(irq, desc);
 509
 510         /*
 511          * sparse_irq_lock protects also show_interrupts() and
 512          * kstat_irq_usr(). Once we deleted the descriptor from the
 513          * sparse tree we can free it. Access in proc will fail to
 514          * lookup the descriptor.
 515          *
 516          * The sysfs entry must be serialized against a concurrent
 517          * irq_sysfs_init() as well.
 518          */
 519         irq_sysfs_del(desc);
 520         delete_irq_desc(irq);
 521
 522         /*
 523          * We free the descriptor, masks and stat fields via RCU. That
 524          * allows demultiplex interrupts to do rcu based management of
 525          * the child interrupts.
 526          * This also allows us to use rcu in kstat_irqs_usr().
 527          */
 528         call_rcu(&desc->rcu, delayed_free_desc);
 529 }
 530
 531 static int alloc_descs(unsigned int start, unsigned int cnt, int node,
 532                        const struct irq_affinity_desc *affinity,
 533                        struct module *owner)
 534 {
 535         struct irq_desc *desc;
 536         int i;
 537
 538         /* Validate affinity mask(s) */
 539         if (affinity) {
 540                 for (i = 0; i < cnt; i++) {
 541                         if (cpumask_empty(&affinity[i].mask))
 542                                 return -EINVAL;
 543                 }
 544         }
 545
 546         for (i = 0; i < cnt; i++) {
 547                 const struct cpumask *mask = NULL;
 548                 unsigned int flags = 0;
 549
 550                 if (affinity) {
 551                         if (affinity->is_managed) {
 552                                 flags = IRQD_AFFINITY_MANAGED |
 553                                         IRQD_MANAGED_SHUTDOWN;
 554                         }
 555                         flags |= IRQD_AFFINITY_SET;
 556                         mask = &affinity->mask;
 557                         node = cpu_to_node(cpumask_first(mask));
 558                         affinity++;
 559                 }
 560
 561                 desc = alloc_desc(start + i, node, flags, mask, owner);
 562                 if (!desc)
 563                         goto err;
 564                 irq_insert_desc(start + i, desc);
 565                 irq_sysfs_add(start + i, desc);
 566                 irq_add_debugfs_entry(start + i, desc);
 567         }
 568         return start;
 569
 570 err:
 571         for (i--; i >= 0; i--)
 572                 free_desc(start + i);
 573         return -ENOMEM;
 574 }
 575
 576 static int irq_expand_nr_irqs(unsigned int nr)
 577 {
 578         if (nr > MAX_SPARSE_IRQS)
 579                 return -ENOMEM;
 580         nr_irqs = nr;
 581         return 0;
 582 }
 583
 584 int __init early_irq_init(void)
 585 {
 586         int i, initcnt, node = first_online_node;
 587         struct irq_desc *desc;
 588
 589         init_irq_default_affinity();
 590
 591         /* Let arch update nr_irqs and return the nr of preallocated irqs */
 592         initcnt = arch_probe_nr_irqs();
 593         printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
 594                NR_IRQS, nr_irqs, initcnt);
 595
 596         if (WARN_ON(nr_irqs > MAX_SPARSE_IRQS))
 597                 nr_irqs = MAX_SPARSE_IRQS;
 598
 599         if (WARN_ON(initcnt > MAX_SPARSE_IRQS))
 600                 initcnt = MAX_SPARSE_IRQS;
 601
 602         if (initcnt > nr_irqs)
 603                 nr_irqs = initcnt;
 604
 605         for (i = 0; i < initcnt; i++) {
 606                 desc = alloc_desc(i, node, 0, NULL, NULL);
 607                 irq_insert_desc(i, desc);
 608         }
 609         return arch_early_irq_init();
 610 }
 611
 612 #else /* !CONFIG_SPARSE_IRQ */
 613
 614 struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
 615         [0 ... NR_IRQS-1] = {
 616                 .handle_irq     = handle_bad_irq,
 617                 .depth          = 1,
 618                 .lock           = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
 619         }
 620 };
 621
 622 int __init early_irq_init(void)
 623 {
 624         int count, i, node = first_online_node;
 625         int ret;
 626
 627         init_irq_default_affinity();
 628
 629         printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
 630
 631         count = ARRAY_SIZE(irq_desc);
 632
 633         for (i = 0; i < count; i++) {
 634                 ret = init_desc(irq_desc + i, i, node, 0, NULL, NULL);
 635                 if (unlikely(ret))
 636                         goto __free_desc_res;
 637         }
 638
 639         return arch_early_irq_init();
 640
 641 __free_desc_res:
 642         while (--i >= 0) {
 643                 free_masks(irq_desc + i);
 644                 free_percpu(irq_desc[i].kstat_irqs);
 645         }
 646
 647         return ret;
 648 }
 649
 650 struct irq_desc *irq_to_desc(unsigned int irq)
 651 {
 652         return (irq < NR_IRQS) ? irq_desc + irq : NULL;
 653 }
 654 EXPORT_SYMBOL(irq_to_desc);
 655
 656 static void free_desc(unsigned int irq)
 657 {
 658         struct irq_desc *desc = irq_to_desc(irq);
 659         unsigned long flags;
 660
 661         raw_spin_lock_irqsave(&desc->lock, flags);
 662         desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
 663         raw_spin_unlock_irqrestore(&desc->lock, flags);
 664         delete_irq_desc(irq);
 665 }
 666
 667 static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
 668                               const struct irq_affinity_desc *affinity,
 669                               struct module *owner)
 670 {
 671         u32 i;
 672
 673         for (i = 0; i < cnt; i++) {
 674                 struct irq_desc *desc = irq_to_desc(start + i);
 675
 676                 desc->owner = owner;
 677                 irq_insert_desc(start + i, desc);
 678         }
 679         return start;
 680 }
 681
 682 static int irq_expand_nr_irqs(unsigned int nr)
 683 {
 684         return -ENOMEM;
 685 }
 686
 687 void irq_mark_irq(unsigned int irq)
 688 {
 689         mutex_lock(&sparse_irq_lock);
 690         irq_insert_desc(irq, irq_desc + irq);
 691         mutex_unlock(&sparse_irq_lock);
 692 }
 693
 694 #ifdef CONFIG_GENERIC_IRQ_LEGACY
 695 void irq_init_desc(unsigned int irq)
 696 {
 697         free_desc(irq);
 698 }
 699 #endif
 700
 701 #endif /* !CONFIG_SPARSE_IRQ */
 702
 703 int handle_irq_desc(struct irq_desc *desc)
 704 {
 705         struct irq_data *data;
 706
 707         if (!desc)
 708                 return -EINVAL;
 709
 710         data = irq_desc_get_irq_data(desc);
 711         if (WARN_ON_ONCE(!in_hardirq() && handle_enforce_irqctx(data)))
 712                 return -EPERM;
 713
 714         generic_handle_irq_desc(desc);
 715         return 0;
 716 }
 717
 718 /**
 719  * generic_handle_irq - Invoke the handler for a particular irq
 720  * @irq:        The irq number to handle
 721  *
 722  * Returns:     0 on success, or -EINVAL if conversion has failed
 723  *
 724  *              This function must be called from an IRQ context with irq regs
 725  *              initialized.
 726   */
 727 int generic_handle_irq(unsigned int irq)
 728 {
 729         return handle_irq_desc(irq_to_desc(irq));
 730 }
 731 EXPORT_SYMBOL_GPL(generic_handle_irq);
 732
 733 /**
 734  * generic_handle_irq_safe - Invoke the handler for a particular irq from any
 735  *                           context.
 736  * @irq:        The irq number to handle
 737  *
 738  * Returns:     0 on success, a negative value on error.
 739  *
 740  * This function can be called from any context (IRQ or process context). It
 741  * will report an error if not invoked from IRQ context and the irq has been
 742  * marked to enforce IRQ-context only.
 743  */
 744 int generic_handle_irq_safe(unsigned int irq)
 745 {
 746         unsigned long flags;
 747         int ret;
 748
 749         local_irq_save(flags);
 750         ret = handle_irq_desc(irq_to_desc(irq));
 751         local_irq_restore(flags);
 752         return ret;
 753 }
 754 EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
 755
 756 #ifdef CONFIG_IRQ_DOMAIN
 757 /**
 758  * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
 759  *                             to a domain.
 760  * @domain:     The domain where to perform the lookup
 761  * @hwirq:      The HW irq number to convert to a logical one
 762  *
 763  * Returns:     0 on success, or -EINVAL if conversion has failed
 764  *
 765  *              This function must be called from an IRQ context with irq regs
 766  *              initialized.
 767  */
 768 int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
 769 {
 770         return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 771 }
 772 EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
 773
 774  /**
 775  * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
 776  *                           to a domain from any context.
 777  * @domain:     The domain where to perform the lookup
 778  * @hwirq:      The HW irq number to convert to a logical one
 779  *
 780  * Returns:     0 on success, a negative value on error.
 781  *
 782  * This function can be called from any context (IRQ or process
 783  * context). If the interrupt is marked as 'enforce IRQ-context only' then
 784  * the function must be invoked from hard interrupt context.
 785  */
 786 int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
 787 {
 788         unsigned long flags;
 789         int ret;
 790
 791         local_irq_save(flags);
 792         ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 793         local_irq_restore(flags);
 794         return ret;
 795 }
 796 EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
 797
 798 /**
 799  * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
 800  *                             to a domain.
 801  * @domain:     The domain where to perform the lookup
 802  * @hwirq:      The HW irq number to convert to a logical one
 803  *
 804  * Returns:     0 on success, or -EINVAL if conversion has failed
 805  *
 806  *              This function must be called from an NMI context with irq regs
 807  *              initialized.
 808  **/
 809 int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq)
 810 {
 811         WARN_ON_ONCE(!in_nmi());
 812         return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 813 }
 814 #endif
 815
 816 /* Dynamic interrupt handling */
 817
 818 /**
 819  * irq_free_descs - free irq descriptors
 820  * @from:       Start of descriptor range
 821  * @cnt:        Number of consecutive irqs to free
 822  */
 823 void irq_free_descs(unsigned int from, unsigned int cnt)
 824 {
 825         int i;
 826
 827         if (from >= nr_irqs || (from + cnt) > nr_irqs)
 828                 return;
 829
 830         mutex_lock(&sparse_irq_lock);
 831         for (i = 0; i < cnt; i++)
 832                 free_desc(from + i);
 833
 834         mutex_unlock(&sparse_irq_lock);
 835 }
 836 EXPORT_SYMBOL_GPL(irq_free_descs);
 837
 838 /**
 839  * __irq_alloc_descs - allocate and initialize a range of irq descriptors
 840  * @irq:        Allocate for specific irq number if irq >= 0
 841  * @from:       Start the search from this irq number
 842  * @cnt:        Number of consecutive irqs to allocate.
 843  * @node:       Preferred node on which the irq descriptor should be allocated
 844  * @owner:      Owning module (can be NULL)
 845  * @affinity:   Optional pointer to an affinity mask array of size @cnt which
 846  *              hints where the irq descriptors should be allocated and which
 847  *              default affinities to use
 848  *
 849  * Returns the first irq number or error code
 850  */
 851 int __ref
 852 __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 853                   struct module *owner, const struct irq_affinity_desc *affinity)
 854 {
 855         int start, ret;
 856
 857         if (!cnt)
 858                 return -EINVAL;
 859
 860         if (irq >= 0) {
 861                 if (from > irq)
 862                         return -EINVAL;
 863                 from = irq;
 864         } else {
 865                 /*
 866                  * For interrupts which are freely allocated the
 867                  * architecture can force a lower bound to the @from
 868                  * argument. x86 uses this to exclude the GSI space.
 869                  */
 870                 from = arch_dynirq_lower_bound(from);
 871         }
 872
 873         mutex_lock(&sparse_irq_lock);
 874
 875         start = irq_find_free_area(from, cnt);
 876         ret = -EEXIST;
 877         if (irq >=0 && start != irq)
 878                 goto unlock;
 879
 880         if (start + cnt > nr_irqs) {
 881                 ret = irq_expand_nr_irqs(start + cnt);
 882                 if (ret)
 883                         goto unlock;
 884         }
 885         ret = alloc_descs(start, cnt, node, affinity, owner);
 886 unlock:
 887         mutex_unlock(&sparse_irq_lock);
 888         return ret;
 889 }
 890 EXPORT_SYMBOL_GPL(__irq_alloc_descs);
 891
 892 /**
 893  * irq_get_next_irq - get next allocated irq number
 894  * @offset:     where to start the search
 895  *
 896  * Returns next irq number after offset or nr_irqs if none is found.
 897  */
 898 unsigned int irq_get_next_irq(unsigned int offset)
 899 {
 900         return irq_find_at_or_after(offset);
 901 }
 902
 903 struct irq_desc *
 904 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
 905                     unsigned int check)
 906 {
 907         struct irq_desc *desc = irq_to_desc(irq);
 908
 909         if (desc) {
 910                 if (check & _IRQ_DESC_CHECK) {
 911                         if ((check & _IRQ_DESC_PERCPU) &&
 912                             !irq_settings_is_per_cpu_devid(desc))
 913                                 return NULL;
 914
 915                         if (!(check & _IRQ_DESC_PERCPU) &&
 916                             irq_settings_is_per_cpu_devid(desc))
 917                                 return NULL;
 918                 }
 919
 920                 if (bus)
 921                         chip_bus_lock(desc);
 922                 raw_spin_lock_irqsave(&desc->lock, *flags);
 923         }
 924         return desc;
 925 }
 926
 927 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
 928         __releases(&desc->lock)
 929 {
 930         raw_spin_unlock_irqrestore(&desc->lock, flags);
 931         if (bus)
 932                 chip_bus_sync_unlock(desc);
 933 }
 934
 935 int irq_set_percpu_devid_partition(unsigned int irq,
 936                                    const struct cpumask *affinity)
 937 {
 938         struct irq_desc *desc = irq_to_desc(irq);
 939
 940         if (!desc || desc->percpu_enabled)
 941                 return -EINVAL;
 942
 943         desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
 944
 945         if (!desc->percpu_enabled)
 946                 return -ENOMEM;
 947
 948         desc->percpu_affinity = affinity ? : cpu_possible_mask;
 949
 950         irq_set_percpu_devid_flags(irq);
 951         return 0;
 952 }
 953
 954 int irq_set_percpu_devid(unsigned int irq)
 955 {
 956         return irq_set_percpu_devid_partition(irq, NULL);
 957 }
 958
 959 int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
 960 {
 961         struct irq_desc *desc = irq_to_desc(irq);
 962
 963         if (!desc || !desc->percpu_enabled)
 964                 return -EINVAL;
 965
 966         if (affinity)
 967                 cpumask_copy(affinity, desc->percpu_affinity);
 968
 969         return 0;
 970 }
 971 EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
 972
 973 void kstat_incr_irq_this_cpu(unsigned int irq)
 974 {
 975         kstat_incr_irqs_this_cpu(irq_to_desc(irq));
 976 }
 977
 978 /**
 979  * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
 980  * @irq:        The interrupt number
 981  * @cpu:        The cpu number
 982  *
 983  * Returns the sum of interrupt counts on @cpu since boot for
 984  * @irq. The caller must ensure that the interrupt is not removed
 985  * concurrently.
 986  */
 987 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 988 {
 989         struct irq_desc *desc = irq_to_desc(irq);
 990
 991         return desc && desc->kstat_irqs ? per_cpu(desc->kstat_irqs->cnt, cpu) : 0;
 992 }
 993
 994 unsigned int kstat_irqs_desc(struct irq_desc *desc, const struct cpumask *cpumask)
 995 {
 996         unsigned int sum = 0;
 997         int cpu;
 998
 999         if (!irq_settings_is_per_cpu_devid(desc) &&
1000             !irq_settings_is_per_cpu(desc) &&
1001             !irq_is_nmi(desc))
1002                 return data_race(desc->tot_count);
1003
1004         for_each_cpu(cpu, cpumask)
1005                 sum += data_race(per_cpu(desc->kstat_irqs->cnt, cpu));
1006         return sum;
1007 }
1008
1009 static unsigned int kstat_irqs(unsigned int irq)
1010 {
1011         struct irq_desc *desc = irq_to_desc(irq);
1012
1013         if (!desc || !desc->kstat_irqs)
1014                 return 0;
1015         return kstat_irqs_desc(desc, cpu_possible_mask);
1016 }
1017
1018 #ifdef CONFIG_GENERIC_IRQ_STAT_SNAPSHOT
1019
1020 void kstat_snapshot_irqs(void)
1021 {
1022         struct irq_desc *desc;
1023         unsigned int irq;
1024
1025         for_each_irq_desc(irq, desc) {
1026                 if (!desc->kstat_irqs)
1027                         continue;
1028                 this_cpu_write(desc->kstat_irqs->ref, this_cpu_read(desc->kstat_irqs->cnt));
1029         }
1030 }
1031
1032 unsigned int kstat_get_irq_since_snapshot(unsigned int irq)
1033 {
1034         struct irq_desc *desc = irq_to_desc(irq);
1035
1036         if (!desc || !desc->kstat_irqs)
1037                 return 0;
1038         return this_cpu_read(desc->kstat_irqs->cnt) - this_cpu_read(desc->kstat_irqs->ref);
1039 }
1040
1041 #endif
1042
1043 /**
1044  * kstat_irqs_usr - Get the statistics for an interrupt from thread context
1045  * @irq:        The interrupt number
1046  *
1047  * Returns the sum of interrupt counts on all cpus since boot for @irq.
1048  *
1049  * It uses rcu to protect the access since a concurrent removal of an
1050  * interrupt descriptor is observing an rcu grace period before
1051  * delayed_free_desc()/irq_kobj_release().
1052  */
1053 unsigned int kstat_irqs_usr(unsigned int irq)
1054 {
1055         unsigned int sum;
1056
1057         rcu_read_lock();
1058         sum = kstat_irqs(irq);
1059         rcu_read_unlock();
1060         return sum;
1061 }
1062
1063 #ifdef CONFIG_LOCKDEP
1064 void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
1065                              struct lock_class_key *request_class)
1066 {
1067         struct irq_desc *desc = irq_to_desc(irq);
1068
1069         if (desc) {
1070                 lockdep_set_class(&desc->lock, lock_class);
1071                 lockdep_set_class(&desc->request_mutex, request_class);
1072         }
1073 }
1074 EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1075 #endif