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v5.9
   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/radix-tree.h>
  16#include <linux/bitmap.h>
  17#include <linux/irqdomain.h>
  18#include <linux/sysfs.h>
 
  19
  20#include "internals.h"
  21
  22/*
  23 * lockdep: we want to handle all irq_desc locks as a single lock-class:
  24 */
  25static struct lock_class_key irq_desc_lock_class;
  26
  27#if defined(CONFIG_SMP)
  28static 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 comandline masks
  35	 */
  36	cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
  37	return 1;
  38}
  39__setup("irqaffinity=", irq_affinity_setup);
  40
  41static 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
  49static void __init init_irq_default_affinity(void)
  50{
  51}
  52#endif
  53
  54#ifdef CONFIG_SMP
  55static 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
  81static 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#else
  97static inline int
  98alloc_masks(struct irq_desc *desc, int node) { return 0; }
  99static inline void
 100desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
 
 101#endif
 102
 103static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
 104			      const struct cpumask *affinity, struct module *owner)
 105{
 106	int cpu;
 107
 108	desc->irq_common_data.handler_data = NULL;
 109	desc->irq_common_data.msi_desc = NULL;
 110
 111	desc->irq_data.common = &desc->irq_common_data;
 112	desc->irq_data.irq = irq;
 113	desc->irq_data.chip = &no_irq_chip;
 114	desc->irq_data.chip_data = NULL;
 115	irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
 116	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
 117	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
 118	desc->handle_irq = handle_bad_irq;
 119	desc->depth = 1;
 120	desc->irq_count = 0;
 121	desc->irqs_unhandled = 0;
 122	desc->tot_count = 0;
 123	desc->name = NULL;
 124	desc->owner = owner;
 125	for_each_possible_cpu(cpu)
 126		*per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
 127	desc_smp_init(desc, node, affinity);
 128}
 129
 130int nr_irqs = NR_IRQS;
 131EXPORT_SYMBOL_GPL(nr_irqs);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 132
 133static DEFINE_MUTEX(sparse_irq_lock);
 134static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 135
 136#ifdef CONFIG_SPARSE_IRQ
 137
 138static void irq_kobj_release(struct kobject *kobj);
 139
 140#ifdef CONFIG_SYSFS
 141static struct kobject *irq_kobj_base;
 142
 143#define IRQ_ATTR_RO(_name) \
 144static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 145
 146static ssize_t per_cpu_count_show(struct kobject *kobj,
 147				  struct kobj_attribute *attr, char *buf)
 148{
 149	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 150	int cpu, irq = desc->irq_data.irq;
 151	ssize_t ret = 0;
 152	char *p = "";
 
 153
 154	for_each_possible_cpu(cpu) {
 155		unsigned int c = kstat_irqs_cpu(irq, cpu);
 156
 157		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
 158		p = ",";
 159	}
 160
 161	ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 162	return ret;
 163}
 164IRQ_ATTR_RO(per_cpu_count);
 165
 166static ssize_t chip_name_show(struct kobject *kobj,
 167			      struct kobj_attribute *attr, char *buf)
 168{
 169	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 170	ssize_t ret = 0;
 171
 172	raw_spin_lock_irq(&desc->lock);
 173	if (desc->irq_data.chip && desc->irq_data.chip->name) {
 174		ret = scnprintf(buf, PAGE_SIZE, "%s\n",
 175				desc->irq_data.chip->name);
 176	}
 177	raw_spin_unlock_irq(&desc->lock);
 178
 179	return ret;
 180}
 181IRQ_ATTR_RO(chip_name);
 182
 183static ssize_t hwirq_show(struct kobject *kobj,
 184			  struct kobj_attribute *attr, char *buf)
 185{
 186	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 187	ssize_t ret = 0;
 188
 189	raw_spin_lock_irq(&desc->lock);
 190	if (desc->irq_data.domain)
 191		ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq);
 192	raw_spin_unlock_irq(&desc->lock);
 193
 194	return ret;
 195}
 196IRQ_ATTR_RO(hwirq);
 197
 198static ssize_t type_show(struct kobject *kobj,
 199			 struct kobj_attribute *attr, char *buf)
 200{
 201	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 202	ssize_t ret = 0;
 203
 204	raw_spin_lock_irq(&desc->lock);
 205	ret = sprintf(buf, "%s\n",
 206		      irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
 207	raw_spin_unlock_irq(&desc->lock);
 208
 209	return ret;
 210
 211}
 212IRQ_ATTR_RO(type);
 213
 214static ssize_t wakeup_show(struct kobject *kobj,
 215			   struct kobj_attribute *attr, char *buf)
 216{
 217	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 218	ssize_t ret = 0;
 219
 220	raw_spin_lock_irq(&desc->lock);
 221	ret = sprintf(buf, "%s\n",
 222		      irqd_is_wakeup_set(&desc->irq_data) ? "enabled" : "disabled");
 223	raw_spin_unlock_irq(&desc->lock);
 224
 225	return ret;
 226
 227}
 228IRQ_ATTR_RO(wakeup);
 229
 230static ssize_t name_show(struct kobject *kobj,
 231			 struct kobj_attribute *attr, char *buf)
 232{
 233	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 234	ssize_t ret = 0;
 235
 236	raw_spin_lock_irq(&desc->lock);
 237	if (desc->name)
 238		ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
 239	raw_spin_unlock_irq(&desc->lock);
 240
 241	return ret;
 242}
 243IRQ_ATTR_RO(name);
 244
 245static ssize_t actions_show(struct kobject *kobj,
 246			    struct kobj_attribute *attr, char *buf)
 247{
 248	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 249	struct irqaction *action;
 250	ssize_t ret = 0;
 251	char *p = "";
 252
 253	raw_spin_lock_irq(&desc->lock);
 254	for (action = desc->action; action != NULL; action = action->next) {
 255		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
 256				 p, action->name);
 257		p = ",";
 258	}
 259	raw_spin_unlock_irq(&desc->lock);
 260
 261	if (ret)
 262		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 263
 264	return ret;
 265}
 266IRQ_ATTR_RO(actions);
 267
 268static struct attribute *irq_attrs[] = {
 269	&per_cpu_count_attr.attr,
 270	&chip_name_attr.attr,
 271	&hwirq_attr.attr,
 272	&type_attr.attr,
 273	&wakeup_attr.attr,
 274	&name_attr.attr,
 275	&actions_attr.attr,
 276	NULL
 277};
 278ATTRIBUTE_GROUPS(irq);
 279
 280static struct kobj_type irq_kobj_type = {
 281	.release	= irq_kobj_release,
 282	.sysfs_ops	= &kobj_sysfs_ops,
 283	.default_groups = irq_groups,
 284};
 285
 286static void irq_sysfs_add(int irq, struct irq_desc *desc)
 287{
 288	if (irq_kobj_base) {
 289		/*
 290		 * Continue even in case of failure as this is nothing
 291		 * crucial.
 
 292		 */
 293		if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
 294			pr_warn("Failed to add kobject for irq %d\n", irq);
 
 
 295	}
 296}
 297
 298static void irq_sysfs_del(struct irq_desc *desc)
 299{
 300	/*
 301	 * If irq_sysfs_init() has not yet been invoked (early boot), then
 302	 * irq_kobj_base is NULL and the descriptor was never added.
 303	 * kobject_del() complains about a object with no parent, so make
 304	 * it conditional.
 305	 */
 306	if (irq_kobj_base)
 307		kobject_del(&desc->kobj);
 308}
 309
 310static int __init irq_sysfs_init(void)
 311{
 312	struct irq_desc *desc;
 313	int irq;
 314
 315	/* Prevent concurrent irq alloc/free */
 316	irq_lock_sparse();
 317
 318	irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
 319	if (!irq_kobj_base) {
 320		irq_unlock_sparse();
 321		return -ENOMEM;
 322	}
 323
 324	/* Add the already allocated interrupts */
 325	for_each_irq_desc(irq, desc)
 326		irq_sysfs_add(irq, desc);
 327	irq_unlock_sparse();
 328
 329	return 0;
 330}
 331postcore_initcall(irq_sysfs_init);
 332
 333#else /* !CONFIG_SYSFS */
 334
 335static struct kobj_type irq_kobj_type = {
 336	.release	= irq_kobj_release,
 337};
 338
 339static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
 340static void irq_sysfs_del(struct irq_desc *desc) {}
 341
 342#endif /* CONFIG_SYSFS */
 343
 344static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
 345
 346static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
 347{
 348	radix_tree_insert(&irq_desc_tree, irq, desc);
 349}
 350
 351struct irq_desc *irq_to_desc(unsigned int irq)
 352{
 353	return radix_tree_lookup(&irq_desc_tree, irq);
 354}
 355EXPORT_SYMBOL(irq_to_desc);
 356
 357static void delete_irq_desc(unsigned int irq)
 358{
 359	radix_tree_delete(&irq_desc_tree, irq);
 360}
 361
 362#ifdef CONFIG_SMP
 363static void free_masks(struct irq_desc *desc)
 364{
 365#ifdef CONFIG_GENERIC_PENDING_IRQ
 366	free_cpumask_var(desc->pending_mask);
 367#endif
 368	free_cpumask_var(desc->irq_common_data.affinity);
 369#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
 370	free_cpumask_var(desc->irq_common_data.effective_affinity);
 371#endif
 372}
 373#else
 374static inline void free_masks(struct irq_desc *desc) { }
 375#endif
 376
 377void irq_lock_sparse(void)
 378{
 379	mutex_lock(&sparse_irq_lock);
 380}
 381
 382void irq_unlock_sparse(void)
 383{
 384	mutex_unlock(&sparse_irq_lock);
 385}
 386
 387static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
 388				   const struct cpumask *affinity,
 389				   struct module *owner)
 390{
 391	struct irq_desc *desc;
 
 392
 393	desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
 394	if (!desc)
 395		return NULL;
 396	/* allocate based on nr_cpu_ids */
 397	desc->kstat_irqs = alloc_percpu(unsigned int);
 398	if (!desc->kstat_irqs)
 399		goto err_desc;
 400
 401	if (alloc_masks(desc, node))
 402		goto err_kstat;
 403
 404	raw_spin_lock_init(&desc->lock);
 405	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
 406	mutex_init(&desc->request_mutex);
 407	init_rcu_head(&desc->rcu);
 408
 409	desc_set_defaults(irq, desc, node, affinity, owner);
 410	irqd_set(&desc->irq_data, flags);
 411	kobject_init(&desc->kobj, &irq_kobj_type);
 412
 413	return desc;
 414
 415err_kstat:
 416	free_percpu(desc->kstat_irqs);
 417err_desc:
 418	kfree(desc);
 419	return NULL;
 420}
 421
 422static void irq_kobj_release(struct kobject *kobj)
 423{
 424	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 425
 426	free_masks(desc);
 427	free_percpu(desc->kstat_irqs);
 428	kfree(desc);
 429}
 430
 431static void delayed_free_desc(struct rcu_head *rhp)
 432{
 433	struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
 434
 435	kobject_put(&desc->kobj);
 436}
 437
 438static void free_desc(unsigned int irq)
 439{
 440	struct irq_desc *desc = irq_to_desc(irq);
 441
 442	irq_remove_debugfs_entry(desc);
 443	unregister_irq_proc(irq, desc);
 444
 445	/*
 446	 * sparse_irq_lock protects also show_interrupts() and
 447	 * kstat_irq_usr(). Once we deleted the descriptor from the
 448	 * sparse tree we can free it. Access in proc will fail to
 449	 * lookup the descriptor.
 450	 *
 451	 * The sysfs entry must be serialized against a concurrent
 452	 * irq_sysfs_init() as well.
 453	 */
 454	irq_sysfs_del(desc);
 455	delete_irq_desc(irq);
 456
 457	/*
 458	 * We free the descriptor, masks and stat fields via RCU. That
 459	 * allows demultiplex interrupts to do rcu based management of
 460	 * the child interrupts.
 461	 * This also allows us to use rcu in kstat_irqs_usr().
 462	 */
 463	call_rcu(&desc->rcu, delayed_free_desc);
 464}
 465
 466static int alloc_descs(unsigned int start, unsigned int cnt, int node,
 467		       const struct irq_affinity_desc *affinity,
 468		       struct module *owner)
 469{
 470	struct irq_desc *desc;
 471	int i;
 472
 473	/* Validate affinity mask(s) */
 474	if (affinity) {
 475		for (i = 0; i < cnt; i++) {
 476			if (cpumask_empty(&affinity[i].mask))
 477				return -EINVAL;
 478		}
 479	}
 480
 481	for (i = 0; i < cnt; i++) {
 482		const struct cpumask *mask = NULL;
 483		unsigned int flags = 0;
 484
 485		if (affinity) {
 486			if (affinity->is_managed) {
 487				flags = IRQD_AFFINITY_MANAGED |
 488					IRQD_MANAGED_SHUTDOWN;
 489			}
 
 490			mask = &affinity->mask;
 491			node = cpu_to_node(cpumask_first(mask));
 492			affinity++;
 493		}
 494
 495		desc = alloc_desc(start + i, node, flags, mask, owner);
 496		if (!desc)
 497			goto err;
 498		irq_insert_desc(start + i, desc);
 499		irq_sysfs_add(start + i, desc);
 500		irq_add_debugfs_entry(start + i, desc);
 501	}
 502	bitmap_set(allocated_irqs, start, cnt);
 503	return start;
 504
 505err:
 506	for (i--; i >= 0; i--)
 507		free_desc(start + i);
 508	return -ENOMEM;
 509}
 510
 511static int irq_expand_nr_irqs(unsigned int nr)
 512{
 513	if (nr > IRQ_BITMAP_BITS)
 514		return -ENOMEM;
 515	nr_irqs = nr;
 516	return 0;
 517}
 518
 519int __init early_irq_init(void)
 520{
 521	int i, initcnt, node = first_online_node;
 522	struct irq_desc *desc;
 523
 524	init_irq_default_affinity();
 525
 526	/* Let arch update nr_irqs and return the nr of preallocated irqs */
 527	initcnt = arch_probe_nr_irqs();
 528	printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
 529	       NR_IRQS, nr_irqs, initcnt);
 530
 531	if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
 532		nr_irqs = IRQ_BITMAP_BITS;
 533
 534	if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
 535		initcnt = IRQ_BITMAP_BITS;
 536
 537	if (initcnt > nr_irqs)
 538		nr_irqs = initcnt;
 539
 540	for (i = 0; i < initcnt; i++) {
 541		desc = alloc_desc(i, node, 0, NULL, NULL);
 542		set_bit(i, allocated_irqs);
 543		irq_insert_desc(i, desc);
 544	}
 545	return arch_early_irq_init();
 546}
 547
 548#else /* !CONFIG_SPARSE_IRQ */
 549
 550struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
 551	[0 ... NR_IRQS-1] = {
 552		.handle_irq	= handle_bad_irq,
 553		.depth		= 1,
 554		.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
 555	}
 556};
 557
 558int __init early_irq_init(void)
 559{
 560	int count, i, node = first_online_node;
 561	struct irq_desc *desc;
 562
 563	init_irq_default_affinity();
 564
 565	printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
 566
 567	desc = irq_desc;
 568	count = ARRAY_SIZE(irq_desc);
 569
 570	for (i = 0; i < count; i++) {
 571		desc[i].kstat_irqs = alloc_percpu(unsigned int);
 572		alloc_masks(&desc[i], node);
 573		raw_spin_lock_init(&desc[i].lock);
 574		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
 575		mutex_init(&desc[i].request_mutex);
 576		desc_set_defaults(i, &desc[i], node, NULL, NULL);
 577	}
 
 578	return arch_early_irq_init();
 
 
 
 
 
 
 
 
 579}
 580
 581struct irq_desc *irq_to_desc(unsigned int irq)
 582{
 583	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
 584}
 585EXPORT_SYMBOL(irq_to_desc);
 586
 587static void free_desc(unsigned int irq)
 588{
 589	struct irq_desc *desc = irq_to_desc(irq);
 590	unsigned long flags;
 591
 592	raw_spin_lock_irqsave(&desc->lock, flags);
 593	desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
 594	raw_spin_unlock_irqrestore(&desc->lock, flags);
 
 595}
 596
 597static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
 598			      const struct irq_affinity_desc *affinity,
 599			      struct module *owner)
 600{
 601	u32 i;
 602
 603	for (i = 0; i < cnt; i++) {
 604		struct irq_desc *desc = irq_to_desc(start + i);
 605
 606		desc->owner = owner;
 
 607	}
 608	bitmap_set(allocated_irqs, start, cnt);
 609	return start;
 610}
 611
 612static int irq_expand_nr_irqs(unsigned int nr)
 613{
 614	return -ENOMEM;
 615}
 616
 617void irq_mark_irq(unsigned int irq)
 618{
 619	mutex_lock(&sparse_irq_lock);
 620	bitmap_set(allocated_irqs, irq, 1);
 621	mutex_unlock(&sparse_irq_lock);
 622}
 623
 624#ifdef CONFIG_GENERIC_IRQ_LEGACY
 625void irq_init_desc(unsigned int irq)
 626{
 627	free_desc(irq);
 628}
 629#endif
 630
 631#endif /* !CONFIG_SPARSE_IRQ */
 632
 633/**
 634 * generic_handle_irq - Invoke the handler for a particular irq
 635 * @irq:	The irq number to handle
 636 *
 637 */
 638int generic_handle_irq(unsigned int irq)
 639{
 640	struct irq_desc *desc = irq_to_desc(irq);
 641	struct irq_data *data;
 642
 643	if (!desc)
 644		return -EINVAL;
 645
 646	data = irq_desc_get_irq_data(desc);
 647	if (WARN_ON_ONCE(!in_irq() && handle_enforce_irqctx(data)))
 648		return -EPERM;
 649
 650	generic_handle_irq_desc(desc);
 651	return 0;
 652}
 653EXPORT_SYMBOL_GPL(generic_handle_irq);
 654
 655#ifdef CONFIG_HANDLE_DOMAIN_IRQ
 656/**
 657 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
 658 * @domain:	The domain where to perform the lookup
 659 * @hwirq:	The HW irq number to convert to a logical one
 660 * @lookup:	Whether to perform the domain lookup or not
 661 * @regs:	Register file coming from the low-level handling code
 662 *
 663 * Returns:	0 on success, or -EINVAL if conversion has failed
 664 */
 665int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
 666			bool lookup, struct pt_regs *regs)
 
 
 667{
 668	struct pt_regs *old_regs = set_irq_regs(regs);
 669	unsigned int irq = hwirq;
 670	int ret = 0;
 671
 672	irq_enter();
 673
 674#ifdef CONFIG_IRQ_DOMAIN
 675	if (lookup)
 676		irq = irq_find_mapping(domain, hwirq);
 677#endif
 678
 679	/*
 680	 * Some hardware gives randomly wrong interrupts.  Rather
 681	 * than crashing, do something sensible.
 682	 */
 683	if (unlikely(!irq || irq >= nr_irqs)) {
 684		ack_bad_irq(irq);
 685		ret = -EINVAL;
 686	} else {
 687		generic_handle_irq(irq);
 688	}
 
 
 
 
 
 689
 690	irq_exit();
 691	set_irq_regs(old_regs);
 
 692	return ret;
 693}
 
 694
 695#ifdef CONFIG_IRQ_DOMAIN
 696/**
 697 * handle_domain_nmi - Invoke the handler for a HW irq belonging to a domain
 
 698 * @domain:	The domain where to perform the lookup
 699 * @hwirq:	The HW irq number to convert to a logical one
 700 * @regs:	Register file coming from the low-level handling code
 701 *
 702 *		This function must be called from an NMI context.
 703 *
 704 * Returns:	0 on success, or -EINVAL if conversion has failed
 
 
 
 705 */
 706int handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq,
 707		      struct pt_regs *regs)
 708{
 709	struct pt_regs *old_regs = set_irq_regs(regs);
 710	unsigned int irq;
 711	int ret = 0;
 712
 713	/*
 714	 * NMI context needs to be setup earlier in order to deal with tracing.
 715	 */
 716	WARN_ON(!in_nmi());
 717
 718	irq = irq_find_mapping(domain, hwirq);
 719
 720	/*
 721	 * ack_bad_irq is not NMI-safe, just report
 722	 * an invalid interrupt.
 723	 */
 724	if (likely(irq))
 725		generic_handle_irq(irq);
 726	else
 727		ret = -EINVAL;
 
 
 
 
 
 
 
 
 728
 729	set_irq_regs(old_regs);
 
 
 730	return ret;
 731}
 732#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 733#endif
 734
 735/* Dynamic interrupt handling */
 736
 737/**
 738 * irq_free_descs - free irq descriptors
 739 * @from:	Start of descriptor range
 740 * @cnt:	Number of consecutive irqs to free
 741 */
 742void irq_free_descs(unsigned int from, unsigned int cnt)
 743{
 744	int i;
 745
 746	if (from >= nr_irqs || (from + cnt) > nr_irqs)
 747		return;
 748
 749	mutex_lock(&sparse_irq_lock);
 750	for (i = 0; i < cnt; i++)
 751		free_desc(from + i);
 752
 753	bitmap_clear(allocated_irqs, from, cnt);
 754	mutex_unlock(&sparse_irq_lock);
 755}
 756EXPORT_SYMBOL_GPL(irq_free_descs);
 757
 758/**
 759 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
 760 * @irq:	Allocate for specific irq number if irq >= 0
 761 * @from:	Start the search from this irq number
 762 * @cnt:	Number of consecutive irqs to allocate.
 763 * @node:	Preferred node on which the irq descriptor should be allocated
 764 * @owner:	Owning module (can be NULL)
 765 * @affinity:	Optional pointer to an affinity mask array of size @cnt which
 766 *		hints where the irq descriptors should be allocated and which
 767 *		default affinities to use
 768 *
 769 * Returns the first irq number or error code
 770 */
 771int __ref
 772__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 773		  struct module *owner, const struct irq_affinity_desc *affinity)
 774{
 775	int start, ret;
 776
 777	if (!cnt)
 778		return -EINVAL;
 779
 780	if (irq >= 0) {
 781		if (from > irq)
 782			return -EINVAL;
 783		from = irq;
 784	} else {
 785		/*
 786		 * For interrupts which are freely allocated the
 787		 * architecture can force a lower bound to the @from
 788		 * argument. x86 uses this to exclude the GSI space.
 789		 */
 790		from = arch_dynirq_lower_bound(from);
 791	}
 792
 793	mutex_lock(&sparse_irq_lock);
 794
 795	start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
 796					   from, cnt, 0);
 797	ret = -EEXIST;
 798	if (irq >=0 && start != irq)
 799		goto unlock;
 800
 801	if (start + cnt > nr_irqs) {
 802		ret = irq_expand_nr_irqs(start + cnt);
 803		if (ret)
 804			goto unlock;
 805	}
 806	ret = alloc_descs(start, cnt, node, affinity, owner);
 807unlock:
 808	mutex_unlock(&sparse_irq_lock);
 809	return ret;
 810}
 811EXPORT_SYMBOL_GPL(__irq_alloc_descs);
 812
 813#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
 814/**
 815 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
 816 * @cnt:	number of interrupts to allocate
 817 * @node:	node on which to allocate
 818 *
 819 * Returns an interrupt number > 0 or 0, if the allocation fails.
 820 */
 821unsigned int irq_alloc_hwirqs(int cnt, int node)
 822{
 823	int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL);
 824
 825	if (irq < 0)
 826		return 0;
 827
 828	for (i = irq; cnt > 0; i++, cnt--) {
 829		if (arch_setup_hwirq(i, node))
 830			goto err;
 831		irq_clear_status_flags(i, _IRQ_NOREQUEST);
 832	}
 833	return irq;
 834
 835err:
 836	for (i--; i >= irq; i--) {
 837		irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
 838		arch_teardown_hwirq(i);
 839	}
 840	irq_free_descs(irq, cnt);
 841	return 0;
 842}
 843EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
 844
 845/**
 846 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
 847 * @from:	Free from irq number
 848 * @cnt:	number of interrupts to free
 849 *
 850 */
 851void irq_free_hwirqs(unsigned int from, int cnt)
 852{
 853	int i, j;
 854
 855	for (i = from, j = cnt; j > 0; i++, j--) {
 856		irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
 857		arch_teardown_hwirq(i);
 858	}
 859	irq_free_descs(from, cnt);
 860}
 861EXPORT_SYMBOL_GPL(irq_free_hwirqs);
 862#endif
 863
 864/**
 865 * irq_get_next_irq - get next allocated irq number
 866 * @offset:	where to start the search
 867 *
 868 * Returns next irq number after offset or nr_irqs if none is found.
 869 */
 870unsigned int irq_get_next_irq(unsigned int offset)
 871{
 872	return find_next_bit(allocated_irqs, nr_irqs, offset);
 873}
 874
 875struct irq_desc *
 876__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
 877		    unsigned int check)
 878{
 879	struct irq_desc *desc = irq_to_desc(irq);
 880
 881	if (desc) {
 882		if (check & _IRQ_DESC_CHECK) {
 883			if ((check & _IRQ_DESC_PERCPU) &&
 884			    !irq_settings_is_per_cpu_devid(desc))
 885				return NULL;
 886
 887			if (!(check & _IRQ_DESC_PERCPU) &&
 888			    irq_settings_is_per_cpu_devid(desc))
 889				return NULL;
 890		}
 891
 892		if (bus)
 893			chip_bus_lock(desc);
 894		raw_spin_lock_irqsave(&desc->lock, *flags);
 895	}
 896	return desc;
 897}
 898
 899void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
 900	__releases(&desc->lock)
 901{
 902	raw_spin_unlock_irqrestore(&desc->lock, flags);
 903	if (bus)
 904		chip_bus_sync_unlock(desc);
 905}
 906
 907int irq_set_percpu_devid_partition(unsigned int irq,
 908				   const struct cpumask *affinity)
 909{
 910	struct irq_desc *desc = irq_to_desc(irq);
 911
 912	if (!desc)
 913		return -EINVAL;
 914
 915	if (desc->percpu_enabled)
 916		return -EINVAL;
 917
 918	desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
 919
 920	if (!desc->percpu_enabled)
 921		return -ENOMEM;
 922
 923	if (affinity)
 924		desc->percpu_affinity = affinity;
 925	else
 926		desc->percpu_affinity = cpu_possible_mask;
 927
 928	irq_set_percpu_devid_flags(irq);
 929	return 0;
 930}
 931
 932int irq_set_percpu_devid(unsigned int irq)
 933{
 934	return irq_set_percpu_devid_partition(irq, NULL);
 935}
 936
 937int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
 938{
 939	struct irq_desc *desc = irq_to_desc(irq);
 940
 941	if (!desc || !desc->percpu_enabled)
 942		return -EINVAL;
 943
 944	if (affinity)
 945		cpumask_copy(affinity, desc->percpu_affinity);
 946
 947	return 0;
 948}
 949EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
 950
 951void kstat_incr_irq_this_cpu(unsigned int irq)
 952{
 953	kstat_incr_irqs_this_cpu(irq_to_desc(irq));
 954}
 955
 956/**
 957 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
 958 * @irq:	The interrupt number
 959 * @cpu:	The cpu number
 960 *
 961 * Returns the sum of interrupt counts on @cpu since boot for
 962 * @irq. The caller must ensure that the interrupt is not removed
 963 * concurrently.
 964 */
 965unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 966{
 967	struct irq_desc *desc = irq_to_desc(irq);
 968
 969	return desc && desc->kstat_irqs ?
 970			*per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
 971}
 972
 973static bool irq_is_nmi(struct irq_desc *desc)
 974{
 975	return desc->istate & IRQS_NMI;
 976}
 977
 978/**
 979 * kstat_irqs - Get the statistics for an interrupt
 980 * @irq:	The interrupt number
 981 *
 982 * Returns the sum of interrupt counts on all cpus since boot for
 983 * @irq. The caller must ensure that the interrupt is not removed
 984 * concurrently.
 985 */
 986unsigned int kstat_irqs(unsigned int irq)
 987{
 988	struct irq_desc *desc = irq_to_desc(irq);
 989	unsigned int sum = 0;
 990	int cpu;
 991
 992	if (!desc || !desc->kstat_irqs)
 993		return 0;
 994	if (!irq_settings_is_per_cpu_devid(desc) &&
 995	    !irq_settings_is_per_cpu(desc) &&
 996	    !irq_is_nmi(desc))
 997	    return desc->tot_count;
 998
 999	for_each_possible_cpu(cpu)
1000		sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
1001	return sum;
1002}
1003
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1004/**
1005 * kstat_irqs_usr - Get the statistics for an interrupt
1006 * @irq:	The interrupt number
1007 *
1008 * Returns the sum of interrupt counts on all cpus since boot for @irq.
1009 * Contrary to kstat_irqs() this can be called from any context.
1010 * It uses rcu since a concurrent removal of an interrupt descriptor is
1011 * observing an rcu grace period before delayed_free_desc()/irq_kobj_release().
 
1012 */
1013unsigned int kstat_irqs_usr(unsigned int irq)
1014{
1015	unsigned int sum;
1016
1017	rcu_read_lock();
1018	sum = kstat_irqs(irq);
1019	rcu_read_unlock();
1020	return sum;
1021}
v6.13.7
   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 */
  25static struct lock_class_key irq_desc_lock_class;
  26
  27#if defined(CONFIG_SMP)
  28static 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
  41static 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
  49static void __init init_irq_default_affinity(void)
  50{
  51}
  52#endif
  53
  54#ifdef CONFIG_SMP
  55static 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
  81static 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
  96static 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
 108static inline int
 109alloc_masks(struct irq_desc *desc, int node) { return 0; }
 110static inline void
 111desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
 112static inline void free_masks(struct irq_desc *desc) { }
 113#endif
 114
 115static 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
 142static unsigned int nr_irqs = NR_IRQS;
 143
 144/**
 145 * irq_get_nr_irqs() - Number of interrupts supported by the system.
 146 */
 147unsigned int irq_get_nr_irqs(void)
 148{
 149	return nr_irqs;
 150}
 151EXPORT_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 */
 159unsigned int irq_set_nr_irqs(unsigned int nr)
 160{
 161	nr_irqs = nr;
 162
 163	return nr;
 164}
 165EXPORT_SYMBOL_GPL(irq_set_nr_irqs);
 166
 167static DEFINE_MUTEX(sparse_irq_lock);
 168static 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
 174static 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
 183static 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
 194static 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
 200static 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
 207static const struct kobj_type irq_kobj_type;
 208#endif
 209
 210static 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
 241static void irq_kobj_release(struct kobject *kobj);
 242
 243#ifdef CONFIG_SYSFS
 244static struct kobject *irq_kobj_base;
 245
 246#define IRQ_ATTR_RO(_name) \
 247static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 248
 249static 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}
 267IRQ_ATTR_RO(per_cpu_count);
 268
 269static 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}
 284IRQ_ATTR_RO(chip_name);
 285
 286static 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}
 299IRQ_ATTR_RO(hwirq);
 300
 301static 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}
 315IRQ_ATTR_RO(type);
 316
 317static 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}
 330IRQ_ATTR_RO(wakeup);
 331
 332static 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}
 345IRQ_ATTR_RO(name);
 346
 347static 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}
 368IRQ_ATTR_RO(actions);
 369
 370static 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};
 380ATTRIBUTE_GROUPS(irq);
 381
 382static 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
 388static 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
 403static 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
 415static 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}
 436postcore_initcall(irq_sysfs_init);
 437
 438#else /* !CONFIG_SYSFS */
 439
 440static const struct kobj_type irq_kobj_type = {
 441	.release	= irq_kobj_release,
 442};
 443
 444static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
 445static void irq_sysfs_del(struct irq_desc *desc) {}
 446
 447#endif /* CONFIG_SYSFS */
 448
 
 
 
 
 
 
 
 449struct 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
 454EXPORT_SYMBOL_GPL(irq_to_desc);
 
 
 
 
 
 
 
 
 
 
 
 
 455#endif
 456
 457void irq_lock_sparse(void)
 458{
 459	mutex_lock(&sparse_irq_lock);
 460}
 461
 462void irq_unlock_sparse(void)
 463{
 464	mutex_unlock(&sparse_irq_lock);
 465}
 466
 467static 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
 487static 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
 496static 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
 503static 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
 531static 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
 570err:
 571	for (i--; i >= 0; i--)
 572		free_desc(start + i);
 573	return -ENOMEM;
 574}
 575
 576static 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
 584int __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
 614struct 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
 622int __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
 650struct irq_desc *irq_to_desc(unsigned int irq)
 651{
 652	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
 653}
 654EXPORT_SYMBOL(irq_to_desc);
 655
 656static 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
 667static 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
 682static int irq_expand_nr_irqs(unsigned int nr)
 683{
 684	return -ENOMEM;
 685}
 686
 687void 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
 695void irq_init_desc(unsigned int irq)
 696{
 697	free_desc(irq);
 698}
 699#endif
 700
 701#endif /* !CONFIG_SPARSE_IRQ */
 702
 703int 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  */
 727int generic_handle_irq(unsigned int irq)
 728{
 729	return handle_irq_desc(irq_to_desc(irq));
 730}
 731EXPORT_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 */
 744int 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}
 754EXPORT_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 */
 768int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
 
 769{
 770	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 771}
 772EXPORT_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 */
 786int 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}
 796EXPORT_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 **/
 809int 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 */
 823void 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}
 836EXPORT_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 */
 851int __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);
 886unlock:
 887	mutex_unlock(&sparse_irq_lock);
 888	return ret;
 889}
 890EXPORT_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 */
 898unsigned int irq_get_next_irq(unsigned int offset)
 899{
 900	return irq_find_at_or_after(offset);
 901}
 902
 903struct 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
 927void __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
 935int 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
 954int irq_set_percpu_devid(unsigned int irq)
 955{
 956	return irq_set_percpu_devid_partition(irq, NULL);
 957}
 958
 959int 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}
 971EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
 972
 973void 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 */
 987unsigned 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
 994unsigned 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
1009static 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
1020void 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
1032unsigned 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 */
1053unsigned 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
1064void __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}
1074EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1075#endif