irqdesc.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
   4 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
   5 *
   6 * This file contains the interrupt descriptor management code. Detailed
   7 * information is available in Documentation/core-api/genericirq.rst
   8 *
   9 */
  10#include <linux/irq.h>
  11#include <linux/slab.h>
  12#include <linux/export.h>
  13#include <linux/interrupt.h>
  14#include <linux/kernel_stat.h>
  15#include <linux/maple_tree.h>
  16#include <linux/irqdomain.h>
  17#include <linux/sysfs.h>
  18#include <linux/string_choices.h>
  19
  20#include "internals.h"
  21
  22/*
  23 * lockdep: we want to handle all irq_desc locks as a single lock-class:
  24 */
  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, struct kobj_attribute *attr, char *buf)
 250{
 251	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 252	ssize_t ret = 0;
 253	char *p = "";
 254	int cpu;
 255
 256	for_each_possible_cpu(cpu) {
 257		unsigned int c = irq_desc_kstat_cpu(desc, cpu);
 258
 259		ret += sysfs_emit_at(buf, ret, "%s%u", p, c);
 260		p = ",";
 261	}
 262
 263	ret += sysfs_emit_at(buf, ret, "\n");
 264	return ret;
 265}
 266IRQ_ATTR_RO(per_cpu_count);
 267
 268static ssize_t chip_name_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 269{
 270	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 271
 272	guard(raw_spinlock_irq)(&desc->lock);
 273	if (desc->irq_data.chip && desc->irq_data.chip->name)
 274		return sysfs_emit(buf, "%s\n", desc->irq_data.chip->name);
 275	return 0;
 276}
 277IRQ_ATTR_RO(chip_name);
 278
 279static ssize_t hwirq_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 280{
 281	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 282
 283	guard(raw_spinlock_irq)(&desc->lock);
 284	if (desc->irq_data.domain)
 285		return sysfs_emit(buf, "%lu\n", desc->irq_data.hwirq);
 286	return 0;
 287}
 288IRQ_ATTR_RO(hwirq);
 289
 290static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 291{
 292	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 293
 294	guard(raw_spinlock_irq)(&desc->lock);
 295	return sysfs_emit(buf, "%s\n", irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
 296
 297}
 298IRQ_ATTR_RO(type);
 299
 300static ssize_t wakeup_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 301{
 302	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 303
 304	guard(raw_spinlock_irq)(&desc->lock);
 305	return sysfs_emit(buf, "%s\n", str_enabled_disabled(irqd_is_wakeup_set(&desc->irq_data)));
 306}
 307IRQ_ATTR_RO(wakeup);
 308
 309static ssize_t name_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 310{
 311	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 312
 313	guard(raw_spinlock_irq)(&desc->lock);
 314	if (desc->name)
 315		return sysfs_emit(buf, "%s\n", desc->name);
 316	return 0;
 317}
 318IRQ_ATTR_RO(name);
 319
 320static ssize_t actions_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 321{
 322	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 323	struct irqaction *action;
 324	ssize_t ret = 0;
 325	char *p = "";
 326
 327	scoped_guard(raw_spinlock_irq, &desc->lock) {
 328		for_each_action_of_desc(desc, action) {
 329			ret += sysfs_emit_at(buf, ret, "%s%s", p, action->name);
 330			p = ",";
 331		}
 332	}
 333
 334	if (ret)
 335		ret += sysfs_emit_at(buf, ret, "\n");
 336	return ret;
 337}
 338IRQ_ATTR_RO(actions);
 339
 340static struct attribute *irq_attrs[] = {
 341	&per_cpu_count_attr.attr,
 342	&chip_name_attr.attr,
 343	&hwirq_attr.attr,
 344	&type_attr.attr,
 345	&wakeup_attr.attr,
 346	&name_attr.attr,
 347	&actions_attr.attr,
 348	NULL
 349};
 350ATTRIBUTE_GROUPS(irq);
 351
 352static const struct kobj_type irq_kobj_type = {
 353	.release	= irq_kobj_release,
 354	.sysfs_ops	= &kobj_sysfs_ops,
 355	.default_groups = irq_groups,
 356};
 357
 358static void irq_sysfs_add(int irq, struct irq_desc *desc)
 359{
 360	if (irq_kobj_base) {
 361		/*
 362		 * Continue even in case of failure as this is nothing
 363		 * crucial and failures in the late irq_sysfs_init()
 364		 * cannot be rolled back.
 365		 */
 366		if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
 367			pr_warn("Failed to add kobject for irq %d\n", irq);
 368		else
 369			desc->istate |= IRQS_SYSFS;
 370	}
 371}
 372
 373static void irq_sysfs_del(struct irq_desc *desc)
 374{
 375	/*
 376	 * Only invoke kobject_del() when kobject_add() was successfully
 377	 * invoked for the descriptor. This covers both early boot, where
 378	 * sysfs is not initialized yet, and the case of a failed
 379	 * kobject_add() invocation.
 380	 */
 381	if (desc->istate & IRQS_SYSFS)
 382		kobject_del(&desc->kobj);
 383}
 384
 385static int __init irq_sysfs_init(void)
 386{
 387	struct irq_desc *desc;
 388	int irq;
 389
 390	/* Prevent concurrent irq alloc/free */
 391	guard(mutex)(&sparse_irq_lock);
 392	irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
 393	if (!irq_kobj_base)
 394		return -ENOMEM;
 395
 396	/* Add the already allocated interrupts */
 397	for_each_irq_desc(irq, desc)
 398		irq_sysfs_add(irq, desc);
 399	return 0;
 400}
 401postcore_initcall(irq_sysfs_init);
 402
 403#else /* !CONFIG_SYSFS */
 404
 405static const struct kobj_type irq_kobj_type = {
 406	.release	= irq_kobj_release,
 407};
 408
 409static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
 410static void irq_sysfs_del(struct irq_desc *desc) {}
 411
 412#endif /* CONFIG_SYSFS */
 413
 414struct irq_desc *irq_to_desc(unsigned int irq)
 415{
 416	return mtree_load(&sparse_irqs, irq);
 417}
 418#ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
 419EXPORT_SYMBOL_GPL(irq_to_desc);
 420#endif
 421
 422void irq_lock_sparse(void)
 423{
 424	mutex_lock(&sparse_irq_lock);
 425}
 426
 427void irq_unlock_sparse(void)
 428{
 429	mutex_unlock(&sparse_irq_lock);
 430}
 431
 432static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
 433				   const struct cpumask *affinity,
 434				   struct module *owner)
 435{
 436	struct irq_desc *desc;
 437	int ret;
 438
 439	desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
 440	if (!desc)
 441		return NULL;
 442
 443	ret = init_desc(desc, irq, node, flags, affinity, owner);
 444	if (unlikely(ret)) {
 445		kfree(desc);
 446		return NULL;
 447	}
 448
 449	return desc;
 450}
 451
 452static void irq_kobj_release(struct kobject *kobj)
 453{
 454	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 455
 456	free_masks(desc);
 457	free_percpu(desc->kstat_irqs);
 458	kfree(desc);
 459}
 460
 461static void delayed_free_desc(struct rcu_head *rhp)
 462{
 463	struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
 464
 465	kobject_put(&desc->kobj);
 466}
 467
 468static void free_desc(unsigned int irq)
 469{
 470	struct irq_desc *desc = irq_to_desc(irq);
 471
 472	irq_remove_debugfs_entry(desc);
 473	unregister_irq_proc(irq, desc);
 474
 475	/*
 476	 * sparse_irq_lock protects also show_interrupts() and
 477	 * kstat_irq_usr(). Once we deleted the descriptor from the
 478	 * sparse tree we can free it. Access in proc will fail to
 479	 * lookup the descriptor.
 480	 *
 481	 * The sysfs entry must be serialized against a concurrent
 482	 * irq_sysfs_init() as well.
 483	 */
 484	irq_sysfs_del(desc);
 485	delete_irq_desc(irq);
 486
 487	/*
 488	 * We free the descriptor, masks and stat fields via RCU. That
 489	 * allows demultiplex interrupts to do rcu based management of
 490	 * the child interrupts.
 491	 * This also allows us to use rcu in kstat_irqs_usr().
 492	 */
 493	call_rcu(&desc->rcu, delayed_free_desc);
 494}
 495
 496static int alloc_descs(unsigned int start, unsigned int cnt, int node,
 497		       const struct irq_affinity_desc *affinity,
 498		       struct module *owner)
 499{
 500	struct irq_desc *desc;
 501	int i;
 502
 503	/* Validate affinity mask(s) */
 504	if (affinity) {
 505		for (i = 0; i < cnt; i++) {
 506			if (cpumask_empty(&affinity[i].mask))
 507				return -EINVAL;
 508		}
 509	}
 510
 511	for (i = 0; i < cnt; i++) {
 512		const struct cpumask *mask = NULL;
 513		unsigned int flags = 0;
 514
 515		if (affinity) {
 516			if (affinity->is_managed) {
 517				flags = IRQD_AFFINITY_MANAGED |
 518					IRQD_MANAGED_SHUTDOWN;
 519			}
 520			flags |= IRQD_AFFINITY_SET;
 521			mask = &affinity->mask;
 522			node = cpu_to_node(cpumask_first(mask));
 523			affinity++;
 524		}
 525
 526		desc = alloc_desc(start + i, node, flags, mask, owner);
 527		if (!desc)
 528			goto err;
 529		irq_insert_desc(start + i, desc);
 530		irq_sysfs_add(start + i, desc);
 531		irq_add_debugfs_entry(start + i, desc);
 532	}
 533	return start;
 534
 535err:
 536	for (i--; i >= 0; i--)
 537		free_desc(start + i);
 538	return -ENOMEM;
 539}
 540
 541static bool irq_expand_nr_irqs(unsigned int nr)
 542{
 543	if (nr > MAX_SPARSE_IRQS)
 544		return false;
 545	nr_irqs = nr;
 546	return true;
 547}
 548
 549int __init early_irq_init(void)
 550{
 551	int i, initcnt, node = first_online_node;
 552	struct irq_desc *desc;
 553
 554	init_irq_default_affinity();
 555
 556	/* Let arch update nr_irqs and return the nr of preallocated irqs */
 557	initcnt = arch_probe_nr_irqs();
 558	printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
 559	       NR_IRQS, nr_irqs, initcnt);
 560
 561	if (WARN_ON(nr_irqs > MAX_SPARSE_IRQS))
 562		nr_irqs = MAX_SPARSE_IRQS;
 563
 564	if (WARN_ON(initcnt > MAX_SPARSE_IRQS))
 565		initcnt = MAX_SPARSE_IRQS;
 566
 567	if (initcnt > nr_irqs)
 568		nr_irqs = initcnt;
 569
 570	for (i = 0; i < initcnt; i++) {
 571		desc = alloc_desc(i, node, 0, NULL, NULL);
 572		irq_insert_desc(i, desc);
 573	}
 574	return arch_early_irq_init();
 575}
 576
 577#else /* !CONFIG_SPARSE_IRQ */
 578
 579struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
 580	[0 ... NR_IRQS-1] = {
 581		.handle_irq	= handle_bad_irq,
 582		.depth		= 1,
 583		.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
 584	}
 585};
 586
 587int __init early_irq_init(void)
 588{
 589	int count, i, node = first_online_node;
 590	int ret;
 591
 592	init_irq_default_affinity();
 593
 594	printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
 595
 596	count = ARRAY_SIZE(irq_desc);
 597
 598	for (i = 0; i < count; i++) {
 599		ret = init_desc(irq_desc + i, i, node, 0, NULL, NULL);
 600		if (unlikely(ret))
 601			goto __free_desc_res;
 602	}
 603
 604	return arch_early_irq_init();
 605
 606__free_desc_res:
 607	while (--i >= 0) {
 608		free_masks(irq_desc + i);
 609		free_percpu(irq_desc[i].kstat_irqs);
 610	}
 611
 612	return ret;
 613}
 614
 615struct irq_desc *irq_to_desc(unsigned int irq)
 616{
 617	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
 618}
 619EXPORT_SYMBOL(irq_to_desc);
 620
 621static void free_desc(unsigned int irq)
 622{
 623	struct irq_desc *desc = irq_to_desc(irq);
 624
 625	scoped_guard(raw_spinlock_irqsave, &desc->lock)
 626		desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
 627	delete_irq_desc(irq);
 628}
 629
 630static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
 631			      const struct irq_affinity_desc *affinity,
 632			      struct module *owner)
 633{
 634	u32 i;
 635
 636	for (i = 0; i < cnt; i++) {
 637		struct irq_desc *desc = irq_to_desc(start + i);
 638
 639		desc->owner = owner;
 640		irq_insert_desc(start + i, desc);
 641	}
 642	return start;
 643}
 644
 645static inline bool irq_expand_nr_irqs(unsigned int nr)
 646{
 647	return false;
 648}
 649
 650void irq_mark_irq(unsigned int irq)
 651{
 652	guard(mutex)(&sparse_irq_lock);
 653	irq_insert_desc(irq, irq_desc + irq);
 654}
 655
 656#endif /* !CONFIG_SPARSE_IRQ */
 657
 658int handle_irq_desc(struct irq_desc *desc)
 659{
 660	struct irq_data *data;
 661
 662	if (!desc)
 663		return -EINVAL;
 664
 665	data = irq_desc_get_irq_data(desc);
 666	if (WARN_ON_ONCE(!in_hardirq() && irqd_is_handle_enforce_irqctx(data)))
 667		return -EPERM;
 668
 669	generic_handle_irq_desc(desc);
 670	return 0;
 671}
 672
 673/**
 674 * generic_handle_irq - Invoke the handler for a particular irq
 675 * @irq:	The irq number to handle
 676 *
 677 * Returns:	0 on success, or -EINVAL if conversion has failed
 678 *
 679 * 		This function must be called from an IRQ context with irq regs
 680 * 		initialized.
 681  */
 682int generic_handle_irq(unsigned int irq)
 683{
 684	return handle_irq_desc(irq_to_desc(irq));
 685}
 686EXPORT_SYMBOL_GPL(generic_handle_irq);
 687
 688/**
 689 * generic_handle_irq_safe - Invoke the handler for a particular irq from any
 690 *			     context.
 691 * @irq:	The irq number to handle
 692 *
 693 * Returns:	0 on success, a negative value on error.
 694 *
 695 * This function can be called from any context (IRQ or process context). It
 696 * will report an error if not invoked from IRQ context and the irq has been
 697 * marked to enforce IRQ-context only.
 698 */
 699int generic_handle_irq_safe(unsigned int irq)
 700{
 701	unsigned long flags;
 702	int ret;
 703
 704	local_irq_save(flags);
 705	ret = handle_irq_desc(irq_to_desc(irq));
 706	local_irq_restore(flags);
 707	return ret;
 708}
 709EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
 710
 711#ifdef CONFIG_IRQ_DOMAIN
 712/**
 713 * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
 714 *                             to a domain.
 715 * @domain:	The domain where to perform the lookup
 716 * @hwirq:	The HW irq number to convert to a logical one
 717 *
 718 * Returns:	0 on success, or -EINVAL if conversion has failed
 719 *
 720 * 		This function must be called from an IRQ context with irq regs
 721 * 		initialized.
 722 */
 723int generic_handle_domain_irq(struct irq_domain *domain, irq_hw_number_t hwirq)
 724{
 725	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 726}
 727EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
 728
 729 /**
 730 * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
 731 *			     to a domain from any context.
 732 * @domain:	The domain where to perform the lookup
 733 * @hwirq:	The HW irq number to convert to a logical one
 734 *
 735 * Returns:	0 on success, a negative value on error.
 736 *
 737 * This function can be called from any context (IRQ or process
 738 * context). If the interrupt is marked as 'enforce IRQ-context only' then
 739 * the function must be invoked from hard interrupt context.
 740 */
 741int generic_handle_domain_irq_safe(struct irq_domain *domain, irq_hw_number_t hwirq)
 742{
 743	unsigned long flags;
 744	int ret;
 745
 746	local_irq_save(flags);
 747	ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 748	local_irq_restore(flags);
 749	return ret;
 750}
 751EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
 752
 753/**
 754 * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
 755 *                             to a domain.
 756 * @domain:	The domain where to perform the lookup
 757 * @hwirq:	The HW irq number to convert to a logical one
 758 *
 759 * Returns:	0 on success, or -EINVAL if conversion has failed
 760 *
 761 * 		This function must be called from an NMI context with irq regs
 762 * 		initialized.
 763 **/
 764int generic_handle_domain_nmi(struct irq_domain *domain, irq_hw_number_t hwirq)
 765{
 766	WARN_ON_ONCE(!in_nmi());
 767	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 768}
 769#endif
 770
 771/* Dynamic interrupt handling */
 772
 773/**
 774 * irq_free_descs - free irq descriptors
 775 * @from:	Start of descriptor range
 776 * @cnt:	Number of consecutive irqs to free
 777 */
 778void irq_free_descs(unsigned int from, unsigned int cnt)
 779{
 780	int i;
 781
 782	if (from >= nr_irqs || (from + cnt) > nr_irqs)
 783		return;
 784
 785	guard(mutex)(&sparse_irq_lock);
 786	for (i = 0; i < cnt; i++)
 787		free_desc(from + i);
 788}
 789EXPORT_SYMBOL_GPL(irq_free_descs);
 790
 791/**
 792 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
 793 * @irq:	Allocate for specific irq number if irq >= 0
 794 * @from:	Start the search from this irq number
 795 * @cnt:	Number of consecutive irqs to allocate.
 796 * @node:	Preferred node on which the irq descriptor should be allocated
 797 * @owner:	Owning module (can be NULL)
 798 * @affinity:	Optional pointer to an affinity mask array of size @cnt which
 799 *		hints where the irq descriptors should be allocated and which
 800 *		default affinities to use
 801 *
 802 * Returns the first irq number or error code
 803 */
 804int __ref __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 805			    struct module *owner, const struct irq_affinity_desc *affinity)
 806{
 807	int start;
 808
 809	if (!cnt)
 810		return -EINVAL;
 811
 812	if (irq >= 0) {
 813		if (from > irq)
 814			return -EINVAL;
 815		from = irq;
 816	} else {
 817		/*
 818		 * For interrupts which are freely allocated the
 819		 * architecture can force a lower bound to the @from
 820		 * argument. x86 uses this to exclude the GSI space.
 821		 */
 822		from = arch_dynirq_lower_bound(from);
 823	}
 824
 825	guard(mutex)(&sparse_irq_lock);
 826
 827	start = irq_find_free_area(from, cnt);
 828	if (irq >=0 && start != irq)
 829		return -EEXIST;
 830
 831	if (start + cnt > nr_irqs) {
 832		if (!irq_expand_nr_irqs(start + cnt))
 833			return -ENOMEM;
 834	}
 835	return alloc_descs(start, cnt, node, affinity, owner);
 836}
 837EXPORT_SYMBOL_GPL(__irq_alloc_descs);
 838
 839/**
 840 * irq_get_next_irq - get next allocated irq number
 841 * @offset:	where to start the search
 842 *
 843 * Returns next irq number after offset or nr_irqs if none is found.
 844 */
 845unsigned int irq_get_next_irq(unsigned int offset)
 846{
 847	return irq_find_at_or_after(offset);
 848}
 849
 850struct irq_desc *__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
 851				     unsigned int check)
 852{
 853	struct irq_desc *desc;
 854
 855	desc = irq_to_desc(irq);
 856	if (!desc)
 857		return NULL;
 858
 859	if (check & _IRQ_DESC_CHECK) {
 860		if ((check & _IRQ_DESC_PERCPU) && !irq_settings_is_per_cpu_devid(desc))
 861			return NULL;
 862
 863		if (!(check & _IRQ_DESC_PERCPU) && irq_settings_is_per_cpu_devid(desc))
 864			return NULL;
 865	}
 866
 867	if (bus)
 868		chip_bus_lock(desc);
 869	raw_spin_lock_irqsave(&desc->lock, *flags);
 870
 871	return desc;
 872}
 873
 874void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
 875	__releases(&desc->lock)
 876{
 877	raw_spin_unlock_irqrestore(&desc->lock, flags);
 878	if (bus)
 879		chip_bus_sync_unlock(desc);
 880}
 881
 882int irq_set_percpu_devid(unsigned int irq)
 883{
 884	struct irq_desc *desc = irq_to_desc(irq);
 885
 886	if (!desc || desc->percpu_enabled)
 887		return -EINVAL;
 888
 889	desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
 890
 891	if (!desc->percpu_enabled)
 892		return -ENOMEM;
 893
 894	irq_set_percpu_devid_flags(irq);
 895	return 0;
 896}
 897
 898void kstat_incr_irq_this_cpu(unsigned int irq)
 899{
 900	kstat_incr_irqs_this_cpu(irq_to_desc(irq));
 901}
 902
 903/**
 904 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
 905 * @irq:	The interrupt number
 906 * @cpu:	The cpu number
 907 *
 908 * Returns the sum of interrupt counts on @cpu since boot for
 909 * @irq. The caller must ensure that the interrupt is not removed
 910 * concurrently.
 911 */
 912unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 913{
 914	struct irq_desc *desc = irq_to_desc(irq);
 915
 916	return desc && desc->kstat_irqs ? per_cpu(desc->kstat_irqs->cnt, cpu) : 0;
 917}
 918
 919static unsigned int kstat_irqs_desc(struct irq_desc *desc, const struct cpumask *cpumask)
 920{
 921	unsigned int sum = 0;
 922	int cpu;
 923
 924	if (!irq_settings_is_per_cpu_devid(desc) &&
 925	    !irq_settings_is_per_cpu(desc) &&
 926	    !irq_is_nmi(desc))
 927		return data_race(desc->tot_count);
 928
 929	for_each_cpu(cpu, cpumask)
 930		sum += data_race(per_cpu(desc->kstat_irqs->cnt, cpu));
 931	return sum;
 932}
 933
 934static unsigned int kstat_irqs(unsigned int irq)
 935{
 936	struct irq_desc *desc = irq_to_desc(irq);
 937
 938	if (!desc || !desc->kstat_irqs)
 939		return 0;
 940	return kstat_irqs_desc(desc, cpu_possible_mask);
 941}
 942
 943#ifdef CONFIG_GENERIC_IRQ_STAT_SNAPSHOT
 944
 945void kstat_snapshot_irqs(void)
 946{
 947	struct irq_desc *desc;
 948	unsigned int irq;
 949
 950	for_each_irq_desc(irq, desc) {
 951		if (!desc->kstat_irqs)
 952			continue;
 953		this_cpu_write(desc->kstat_irqs->ref, this_cpu_read(desc->kstat_irqs->cnt));
 954	}
 955}
 956
 957unsigned int kstat_get_irq_since_snapshot(unsigned int irq)
 958{
 959	struct irq_desc *desc = irq_to_desc(irq);
 960
 961	if (!desc || !desc->kstat_irqs)
 962		return 0;
 963	return this_cpu_read(desc->kstat_irqs->cnt) - this_cpu_read(desc->kstat_irqs->ref);
 964}
 965
 966#endif
 967
 968/**
 969 * kstat_irqs_usr - Get the statistics for an interrupt from thread context
 970 * @irq:	The interrupt number
 971 *
 972 * Returns the sum of interrupt counts on all cpus since boot for @irq.
 973 *
 974 * It uses rcu to protect the access since a concurrent removal of an
 975 * interrupt descriptor is observing an rcu grace period before
 976 * delayed_free_desc()/irq_kobj_release().
 977 */
 978unsigned int kstat_irqs_usr(unsigned int irq)
 979{
 980	unsigned int sum;
 981
 982	rcu_read_lock();
 983	sum = kstat_irqs(irq);
 984	rcu_read_unlock();
 985	return sum;
 986}
 987
 988#ifdef CONFIG_LOCKDEP
 989void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
 990			     struct lock_class_key *request_class)
 991{
 992	struct irq_desc *desc = irq_to_desc(irq);
 993
 994	if (desc) {
 995		lockdep_set_class(&desc->lock, lock_class);
 996		lockdep_set_class(&desc->request_mutex, request_class);
 997	}
 998}
 999EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1000#endif