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 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
 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	ssize_t ret = 0;
151	char *p = "";
152	int cpu;
153
154	for_each_possible_cpu(cpu) {
155		unsigned int c = irq_desc_kstat_cpu(desc, 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, "%lu\n", 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_each_action_of_desc(desc, action) {
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 and failures in the late irq_sysfs_init()
292		 * cannot be rolled back.
293		 */
294		if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
295			pr_warn("Failed to add kobject for irq %d\n", irq);
296		else
297			desc->istate |= IRQS_SYSFS;
298	}
299}
300
301static void irq_sysfs_del(struct irq_desc *desc)
302{
303	/*
304	 * Only invoke kobject_del() when kobject_add() was successfully
305	 * invoked for the descriptor. This covers both early boot, where
306	 * sysfs is not initialized yet, and the case of a failed
307	 * kobject_add() invocation.
308	 */
309	if (desc->istate & IRQS_SYSFS)
310		kobject_del(&desc->kobj);
311}
312
313static int __init irq_sysfs_init(void)
314{
315	struct irq_desc *desc;
316	int irq;
317
318	/* Prevent concurrent irq alloc/free */
319	irq_lock_sparse();
320
321	irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
322	if (!irq_kobj_base) {
323		irq_unlock_sparse();
324		return -ENOMEM;
325	}
326
327	/* Add the already allocated interrupts */
328	for_each_irq_desc(irq, desc)
329		irq_sysfs_add(irq, desc);
330	irq_unlock_sparse();
331
332	return 0;
333}
334postcore_initcall(irq_sysfs_init);
335
336#else /* !CONFIG_SYSFS */
337
338static struct kobj_type irq_kobj_type = {
339	.release	= irq_kobj_release,
340};
341
342static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
343static void irq_sysfs_del(struct irq_desc *desc) {}
344
345#endif /* CONFIG_SYSFS */
346
347static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
348
349static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
350{
351	radix_tree_insert(&irq_desc_tree, irq, desc);
352}
353
354struct irq_desc *irq_to_desc(unsigned int irq)
355{
356	return radix_tree_lookup(&irq_desc_tree, irq);
357}
358#ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
359EXPORT_SYMBOL_GPL(irq_to_desc);
360#endif
361
362static void delete_irq_desc(unsigned int irq)
363{
364	radix_tree_delete(&irq_desc_tree, irq);
365}
366
367#ifdef CONFIG_SMP
368static void free_masks(struct irq_desc *desc)
369{
370#ifdef CONFIG_GENERIC_PENDING_IRQ
371	free_cpumask_var(desc->pending_mask);
372#endif
373	free_cpumask_var(desc->irq_common_data.affinity);
374#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
375	free_cpumask_var(desc->irq_common_data.effective_affinity);
376#endif
377}
378#else
379static inline void free_masks(struct irq_desc *desc) { }
380#endif
381
382void irq_lock_sparse(void)
383{
384	mutex_lock(&sparse_irq_lock);
385}
386
387void irq_unlock_sparse(void)
388{
389	mutex_unlock(&sparse_irq_lock);
390}
391
392static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
393				   const struct cpumask *affinity,
394				   struct module *owner)
395{
396	struct irq_desc *desc;
 
397
398	desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
399	if (!desc)
400		return NULL;
401	/* allocate based on nr_cpu_ids */
402	desc->kstat_irqs = alloc_percpu(unsigned int);
403	if (!desc->kstat_irqs)
404		goto err_desc;
405
406	if (alloc_masks(desc, node))
407		goto err_kstat;
408
409	raw_spin_lock_init(&desc->lock);
410	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
411	mutex_init(&desc->request_mutex);
412	init_rcu_head(&desc->rcu);
413	init_waitqueue_head(&desc->wait_for_threads);
414
415	desc_set_defaults(irq, desc, node, affinity, owner);
416	irqd_set(&desc->irq_data, flags);
417	kobject_init(&desc->kobj, &irq_kobj_type);
418
419	return desc;
420
421err_kstat:
422	free_percpu(desc->kstat_irqs);
423err_desc:
424	kfree(desc);
425	return NULL;
426}
427
428static void irq_kobj_release(struct kobject *kobj)
429{
430	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
431
432	free_masks(desc);
433	free_percpu(desc->kstat_irqs);
434	kfree(desc);
435}
436
437static void delayed_free_desc(struct rcu_head *rhp)
438{
439	struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
440
441	kobject_put(&desc->kobj);
442}
443
444static void free_desc(unsigned int irq)
445{
446	struct irq_desc *desc = irq_to_desc(irq);
447
448	irq_remove_debugfs_entry(desc);
449	unregister_irq_proc(irq, desc);
450
451	/*
452	 * sparse_irq_lock protects also show_interrupts() and
453	 * kstat_irq_usr(). Once we deleted the descriptor from the
454	 * sparse tree we can free it. Access in proc will fail to
455	 * lookup the descriptor.
456	 *
457	 * The sysfs entry must be serialized against a concurrent
458	 * irq_sysfs_init() as well.
459	 */
460	irq_sysfs_del(desc);
461	delete_irq_desc(irq);
 
462
463	/*
464	 * We free the descriptor, masks and stat fields via RCU. That
465	 * allows demultiplex interrupts to do rcu based management of
466	 * the child interrupts.
467	 * This also allows us to use rcu in kstat_irqs_usr().
468	 */
469	call_rcu(&desc->rcu, delayed_free_desc);
470}
471
472static int alloc_descs(unsigned int start, unsigned int cnt, int node,
473		       const struct irq_affinity_desc *affinity,
474		       struct module *owner)
475{
476	struct irq_desc *desc;
477	int i;
478
479	/* Validate affinity mask(s) */
480	if (affinity) {
481		for (i = 0; i < cnt; i++) {
482			if (cpumask_empty(&affinity[i].mask))
483				return -EINVAL;
484		}
485	}
486
487	for (i = 0; i < cnt; i++) {
488		const struct cpumask *mask = NULL;
489		unsigned int flags = 0;
490
491		if (affinity) {
492			if (affinity->is_managed) {
493				flags = IRQD_AFFINITY_MANAGED |
494					IRQD_MANAGED_SHUTDOWN;
495			}
496			mask = &affinity->mask;
497			node = cpu_to_node(cpumask_first(mask));
498			affinity++;
499		}
500
501		desc = alloc_desc(start + i, node, flags, mask, owner);
502		if (!desc)
503			goto err;
 
504		irq_insert_desc(start + i, desc);
505		irq_sysfs_add(start + i, desc);
506		irq_add_debugfs_entry(start + i, desc);
507	}
508	bitmap_set(allocated_irqs, start, cnt);
509	return start;
510
511err:
512	for (i--; i >= 0; i--)
513		free_desc(start + i);
 
 
 
 
514	return -ENOMEM;
515}
516
517static int irq_expand_nr_irqs(unsigned int nr)
518{
519	if (nr > IRQ_BITMAP_BITS)
520		return -ENOMEM;
521	nr_irqs = nr;
522	return 0;
523}
524
525int __init early_irq_init(void)
526{
527	int i, initcnt, node = first_online_node;
528	struct irq_desc *desc;
529
530	init_irq_default_affinity();
531
532	/* Let arch update nr_irqs and return the nr of preallocated irqs */
533	initcnt = arch_probe_nr_irqs();
534	printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
535	       NR_IRQS, nr_irqs, initcnt);
536
537	if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
538		nr_irqs = IRQ_BITMAP_BITS;
539
540	if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
541		initcnt = IRQ_BITMAP_BITS;
542
543	if (initcnt > nr_irqs)
544		nr_irqs = initcnt;
545
546	for (i = 0; i < initcnt; i++) {
547		desc = alloc_desc(i, node, 0, NULL, NULL);
548		set_bit(i, allocated_irqs);
549		irq_insert_desc(i, desc);
550	}
551	return arch_early_irq_init();
552}
553
554#else /* !CONFIG_SPARSE_IRQ */
555
556struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
557	[0 ... NR_IRQS-1] = {
558		.handle_irq	= handle_bad_irq,
559		.depth		= 1,
560		.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
561	}
562};
563
564int __init early_irq_init(void)
565{
566	int count, i, node = first_online_node;
567	struct irq_desc *desc;
568
569	init_irq_default_affinity();
570
571	printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
572
573	desc = irq_desc;
574	count = ARRAY_SIZE(irq_desc);
575
576	for (i = 0; i < count; i++) {
577		desc[i].kstat_irqs = alloc_percpu(unsigned int);
578		alloc_masks(&desc[i], node);
579		raw_spin_lock_init(&desc[i].lock);
580		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
581		mutex_init(&desc[i].request_mutex);
582		init_waitqueue_head(&desc[i].wait_for_threads);
583		desc_set_defaults(i, &desc[i], node, NULL, NULL);
584	}
585	return arch_early_irq_init();
586}
587
588struct irq_desc *irq_to_desc(unsigned int irq)
589{
590	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
591}
592EXPORT_SYMBOL(irq_to_desc);
593
594static void free_desc(unsigned int irq)
595{
596	struct irq_desc *desc = irq_to_desc(irq);
597	unsigned long flags;
598
599	raw_spin_lock_irqsave(&desc->lock, flags);
600	desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
601	raw_spin_unlock_irqrestore(&desc->lock, flags);
602}
603
604static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
605			      const struct irq_affinity_desc *affinity,
606			      struct module *owner)
607{
608	u32 i;
609
610	for (i = 0; i < cnt; i++) {
611		struct irq_desc *desc = irq_to_desc(start + i);
612
613		desc->owner = owner;
614	}
615	bitmap_set(allocated_irqs, start, cnt);
616	return start;
617}
618
619static int irq_expand_nr_irqs(unsigned int nr)
620{
621	return -ENOMEM;
622}
623
624void irq_mark_irq(unsigned int irq)
625{
626	mutex_lock(&sparse_irq_lock);
627	bitmap_set(allocated_irqs, irq, 1);
628	mutex_unlock(&sparse_irq_lock);
629}
630
631#ifdef CONFIG_GENERIC_IRQ_LEGACY
632void irq_init_desc(unsigned int irq)
633{
634	free_desc(irq);
635}
636#endif
637
638#endif /* !CONFIG_SPARSE_IRQ */
639
640int handle_irq_desc(struct irq_desc *desc)
641{
642	struct irq_data *data;
643
644	if (!desc)
645		return -EINVAL;
646
647	data = irq_desc_get_irq_data(desc);
648	if (WARN_ON_ONCE(!in_hardirq() && handle_enforce_irqctx(data)))
649		return -EPERM;
650
651	generic_handle_irq_desc(desc);
652	return 0;
653}
654
655/**
656 * generic_handle_irq - Invoke the handler for a particular irq
657 * @irq:	The irq number to handle
658 *
659 * Returns:	0 on success, or -EINVAL if conversion has failed
660 *
661 * 		This function must be called from an IRQ context with irq regs
662 * 		initialized.
663  */
664int generic_handle_irq(unsigned int irq)
665{
666	return handle_irq_desc(irq_to_desc(irq));
667}
668EXPORT_SYMBOL_GPL(generic_handle_irq);
669
670/**
671 * generic_handle_irq_safe - Invoke the handler for a particular irq from any
672 *			     context.
673 * @irq:	The irq number to handle
674 *
675 * Returns:	0 on success, a negative value on error.
676 *
677 * This function can be called from any context (IRQ or process context). It
678 * will report an error if not invoked from IRQ context and the irq has been
679 * marked to enforce IRQ-context only.
680 */
681int generic_handle_irq_safe(unsigned int irq)
682{
683	unsigned long flags;
684	int ret;
685
686	local_irq_save(flags);
687	ret = handle_irq_desc(irq_to_desc(irq));
688	local_irq_restore(flags);
689	return ret;
690}
691EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
692
693#ifdef CONFIG_IRQ_DOMAIN
694/**
695 * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
696 *                             to a domain.
697 * @domain:	The domain where to perform the lookup
698 * @hwirq:	The HW irq number to convert to a logical one
699 *
700 * Returns:	0 on success, or -EINVAL if conversion has failed
701 *
702 * 		This function must be called from an IRQ context with irq regs
703 * 		initialized.
704 */
705int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
706{
707	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
708}
709EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
710
711 /**
712 * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
713 *			     to a domain from any context.
714 * @domain:	The domain where to perform the lookup
715 * @hwirq:	The HW irq number to convert to a logical one
716 *
717 * Returns:	0 on success, a negative value on error.
718 *
719 * This function can be called from any context (IRQ or process
720 * context). If the interrupt is marked as 'enforce IRQ-context only' then
721 * the function must be invoked from hard interrupt context.
722 */
723int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
724{
725	unsigned long flags;
726	int ret;
727
728	local_irq_save(flags);
729	ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
730	local_irq_restore(flags);
731	return ret;
732}
733EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
734
735/**
736 * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
737 *                             to a domain.
738 * @domain:	The domain where to perform the lookup
739 * @hwirq:	The HW irq number to convert to a logical one
740 *
741 * Returns:	0 on success, or -EINVAL if conversion has failed
742 *
743 * 		This function must be called from an NMI context with irq regs
744 * 		initialized.
745 **/
746int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq)
747{
748	WARN_ON_ONCE(!in_nmi());
749	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
750}
751#endif
752
753/* Dynamic interrupt handling */
754
755/**
756 * irq_free_descs - free irq descriptors
757 * @from:	Start of descriptor range
758 * @cnt:	Number of consecutive irqs to free
759 */
760void irq_free_descs(unsigned int from, unsigned int cnt)
761{
762	int i;
763
764	if (from >= nr_irqs || (from + cnt) > nr_irqs)
765		return;
766
767	mutex_lock(&sparse_irq_lock);
768	for (i = 0; i < cnt; i++)
769		free_desc(from + i);
770
 
771	bitmap_clear(allocated_irqs, from, cnt);
772	mutex_unlock(&sparse_irq_lock);
773}
774EXPORT_SYMBOL_GPL(irq_free_descs);
775
776/**
777 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
778 * @irq:	Allocate for specific irq number if irq >= 0
779 * @from:	Start the search from this irq number
780 * @cnt:	Number of consecutive irqs to allocate.
781 * @node:	Preferred node on which the irq descriptor should be allocated
782 * @owner:	Owning module (can be NULL)
783 * @affinity:	Optional pointer to an affinity mask array of size @cnt which
784 *		hints where the irq descriptors should be allocated and which
785 *		default affinities to use
786 *
787 * Returns the first irq number or error code
788 */
789int __ref
790__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
791		  struct module *owner, const struct irq_affinity_desc *affinity)
792{
793	int start, ret;
794
795	if (!cnt)
796		return -EINVAL;
797
798	if (irq >= 0) {
799		if (from > irq)
800			return -EINVAL;
801		from = irq;
802	} else {
803		/*
804		 * For interrupts which are freely allocated the
805		 * architecture can force a lower bound to the @from
806		 * argument. x86 uses this to exclude the GSI space.
807		 */
808		from = arch_dynirq_lower_bound(from);
809	}
810
811	mutex_lock(&sparse_irq_lock);
812
813	start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
814					   from, cnt, 0);
815	ret = -EEXIST;
816	if (irq >=0 && start != irq)
817		goto unlock;
818
819	if (start + cnt > nr_irqs) {
820		ret = irq_expand_nr_irqs(start + cnt);
821		if (ret)
822			goto unlock;
823	}
824	ret = alloc_descs(start, cnt, node, affinity, owner);
825unlock:
 
 
 
 
826	mutex_unlock(&sparse_irq_lock);
827	return ret;
828}
829EXPORT_SYMBOL_GPL(__irq_alloc_descs);
830
831/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
832 * irq_get_next_irq - get next allocated irq number
833 * @offset:	where to start the search
834 *
835 * Returns next irq number after offset or nr_irqs if none is found.
836 */
837unsigned int irq_get_next_irq(unsigned int offset)
838{
839	return find_next_bit(allocated_irqs, nr_irqs, offset);
840}
841
842struct irq_desc *
843__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
844		    unsigned int check)
845{
846	struct irq_desc *desc = irq_to_desc(irq);
847
848	if (desc) {
849		if (check & _IRQ_DESC_CHECK) {
850			if ((check & _IRQ_DESC_PERCPU) &&
851			    !irq_settings_is_per_cpu_devid(desc))
852				return NULL;
853
854			if (!(check & _IRQ_DESC_PERCPU) &&
855			    irq_settings_is_per_cpu_devid(desc))
856				return NULL;
857		}
858
859		if (bus)
860			chip_bus_lock(desc);
861		raw_spin_lock_irqsave(&desc->lock, *flags);
862	}
863	return desc;
864}
865
866void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
867	__releases(&desc->lock)
868{
869	raw_spin_unlock_irqrestore(&desc->lock, flags);
870	if (bus)
871		chip_bus_sync_unlock(desc);
872}
873
874int irq_set_percpu_devid_partition(unsigned int irq,
875				   const struct cpumask *affinity)
876{
877	struct irq_desc *desc = irq_to_desc(irq);
878
879	if (!desc)
880		return -EINVAL;
881
882	if (desc->percpu_enabled)
883		return -EINVAL;
884
885	desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
886
887	if (!desc->percpu_enabled)
888		return -ENOMEM;
889
890	if (affinity)
891		desc->percpu_affinity = affinity;
892	else
893		desc->percpu_affinity = cpu_possible_mask;
894
895	irq_set_percpu_devid_flags(irq);
896	return 0;
897}
898
899int irq_set_percpu_devid(unsigned int irq)
900{
901	return irq_set_percpu_devid_partition(irq, NULL);
902}
903
904int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
905{
906	struct irq_desc *desc = irq_to_desc(irq);
 
907
908	if (!desc || !desc->percpu_enabled)
909		return -EINVAL;
910
911	if (affinity)
912		cpumask_copy(affinity, desc->percpu_affinity);
913
914	return 0;
915}
916EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
917
918void kstat_incr_irq_this_cpu(unsigned int irq)
919{
920	kstat_incr_irqs_this_cpu(irq_to_desc(irq));
921}
922
923/**
924 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
925 * @irq:	The interrupt number
926 * @cpu:	The cpu number
927 *
928 * Returns the sum of interrupt counts on @cpu since boot for
929 * @irq. The caller must ensure that the interrupt is not removed
930 * concurrently.
931 */
932unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
933{
934	struct irq_desc *desc = irq_to_desc(irq);
935
936	return desc && desc->kstat_irqs ?
937			*per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
938}
939
940static bool irq_is_nmi(struct irq_desc *desc)
941{
942	return desc->istate & IRQS_NMI;
943}
944
945static unsigned int kstat_irqs(unsigned int irq)
946{
947	struct irq_desc *desc = irq_to_desc(irq);
948	unsigned int sum = 0;
949	int cpu;
 
950
951	if (!desc || !desc->kstat_irqs)
952		return 0;
953	if (!irq_settings_is_per_cpu_devid(desc) &&
954	    !irq_settings_is_per_cpu(desc) &&
955	    !irq_is_nmi(desc))
956		return data_race(desc->tot_count);
957
958	for_each_possible_cpu(cpu)
959		sum += data_race(*per_cpu_ptr(desc->kstat_irqs, cpu));
960	return sum;
961}
962
963/**
964 * kstat_irqs_usr - Get the statistics for an interrupt from thread context
965 * @irq:	The interrupt number
966 *
967 * Returns the sum of interrupt counts on all cpus since boot for @irq.
968 *
969 * It uses rcu to protect the access since a concurrent removal of an
970 * interrupt descriptor is observing an rcu grace period before
971 * delayed_free_desc()/irq_kobj_release().
972 */
973unsigned int kstat_irqs_usr(unsigned int irq)
974{
975	unsigned int sum;
976
977	rcu_read_lock();
978	sum = kstat_irqs(irq);
979	rcu_read_unlock();
980	return sum;
981}
982
983#ifdef CONFIG_LOCKDEP
984void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
985			     struct lock_class_key *request_class)
986{
987	struct irq_desc *desc = irq_to_desc(irq);
988
989	if (desc) {
990		lockdep_set_class(&desc->lock, lock_class);
991		lockdep_set_class(&desc->request_mutex, request_class);
992	}
993}
994EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
995#endif