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 */
  24static struct lock_class_key irq_desc_lock_class;
  25
  26#if defined(CONFIG_SMP)
  27static 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
  40static 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
  48static void __init init_irq_default_affinity(void)
  49{
  50}
  51#endif
  52
  53#ifdef CONFIG_SMP
  54static 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
  80static 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
  95static 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
 107static inline int
 108alloc_masks(struct irq_desc *desc, int node) { return 0; }
 109static inline void
 110desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
 111static inline void free_masks(struct irq_desc *desc) { }
 112#endif
 113
 114static 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
 141int nr_irqs = NR_IRQS;
 142EXPORT_SYMBOL_GPL(nr_irqs);
 143
 144static DEFINE_MUTEX(sparse_irq_lock);
 145static 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
 151static 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
 160static 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
 168static 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
 174static 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
 181static const struct kobj_type irq_kobj_type;
 182#endif
 183
 184static 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
 215static void irq_kobj_release(struct kobject *kobj);
 216
 217#ifdef CONFIG_SYSFS
 218static struct kobject *irq_kobj_base;
 219
 220#define IRQ_ATTR_RO(_name) \
 221static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 222
 223static 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}
 241IRQ_ATTR_RO(per_cpu_count);
 242
 243static 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}
 258IRQ_ATTR_RO(chip_name);
 259
 260static 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}
 273IRQ_ATTR_RO(hwirq);
 274
 275static 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}
 289IRQ_ATTR_RO(type);
 290
 291static 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}
 305IRQ_ATTR_RO(wakeup);
 306
 307static 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}
 320IRQ_ATTR_RO(name);
 321
 322static 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}
 343IRQ_ATTR_RO(actions);
 344
 345static 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};
 355ATTRIBUTE_GROUPS(irq);
 356
 357static 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
 363static 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
 378static 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
 390static 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}
 411postcore_initcall(irq_sysfs_init);
 412
 413#else /* !CONFIG_SYSFS */
 414
 415static const struct kobj_type irq_kobj_type = {
 416	.release	= irq_kobj_release,
 417};
 418
 419static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
 420static void irq_sysfs_del(struct irq_desc *desc) {}
 421
 422#endif /* CONFIG_SYSFS */
 423
 424struct 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
 429EXPORT_SYMBOL_GPL(irq_to_desc);
 430#endif
 431
 432void irq_lock_sparse(void)
 433{
 434	mutex_lock(&sparse_irq_lock);
 435}
 436
 437void irq_unlock_sparse(void)
 438{
 439	mutex_unlock(&sparse_irq_lock);
 440}
 441
 442static 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
 462static 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
 471static 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
 478static 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
 506static 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
 544err:
 545	for (i--; i >= 0; i--)
 546		free_desc(start + i);
 
 
 
 
 547	return -ENOMEM;
 548}
 549
 550static 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
 558int __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
 588struct 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
 596int __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
 624struct irq_desc *irq_to_desc(unsigned int irq)
 625{
 626	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
 627}
 628EXPORT_SYMBOL(irq_to_desc);
 629
 630static 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
 641static 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
 656static int irq_expand_nr_irqs(unsigned int nr)
 657{
 658	return -ENOMEM;
 659}
 660
 661void 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
 669void irq_init_desc(unsigned int irq)
 670{
 671	free_desc(irq);
 672}
 673#endif
 674
 675#endif /* !CONFIG_SPARSE_IRQ */
 676
 677int 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  */
 701int generic_handle_irq(unsigned int irq)
 702{
 703	return handle_irq_desc(irq_to_desc(irq));
 704}
 705EXPORT_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 */
 718int 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}
 728EXPORT_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 */
 742int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
 743{
 744	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 745}
 746EXPORT_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 */
 760int 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}
 770EXPORT_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 **/
 783int 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 */
 797void 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}
 810EXPORT_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 */
 825int __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);
 860unlock:
 
 
 
 
 861	mutex_unlock(&sparse_irq_lock);
 862	return ret;
 863}
 864EXPORT_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 */
 872unsigned int irq_get_next_irq(unsigned int offset)
 873{
 874	return irq_find_at_or_after(offset);
 875}
 876
 877struct 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
 901void __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
 909int 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
 934int irq_set_percpu_devid(unsigned int irq)
 935{
 936	return irq_set_percpu_devid_partition(irq, NULL);
 937}
 938
 939int 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}
 951EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
 952
 953void 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 */
 967unsigned 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
 975static bool irq_is_nmi(struct irq_desc *desc)
 976{
 977	return desc->istate & IRQS_NMI;
 978}
 979
 980static 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 */
1008unsigned 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
1019void __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}
1029EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1030#endif