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