xref: /linux/kernel/irq/irqdesc.c (revision 40ccd6aa3e2e05be93394e3cd560c718dedfcc77)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
4  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
5  *
6  * This file contains the interrupt descriptor management code. Detailed
7  * information is available in Documentation/core-api/genericirq.rst
8  *
9  */
10 #include <linux/irq.h>
11 #include <linux/slab.h>
12 #include <linux/export.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel_stat.h>
15 #include <linux/maple_tree.h>
16 #include <linux/irqdomain.h>
17 #include <linux/sysfs.h>
18 
19 #include "internals.h"
20 
21 /*
22  * lockdep: we want to handle all irq_desc locks as a single lock-class:
23  */
24 static struct lock_class_key irq_desc_lock_class;
25 
26 #if defined(CONFIG_SMP)
27 static int __init irq_affinity_setup(char *str)
28 {
29 	alloc_bootmem_cpumask_var(&irq_default_affinity);
30 	cpulist_parse(str, irq_default_affinity);
31 	/*
32 	 * Set at least the boot cpu. We don't want to end up with
33 	 * bugreports caused by random commandline masks
34 	 */
35 	cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
36 	return 1;
37 }
38 __setup("irqaffinity=", irq_affinity_setup);
39 
40 static void __init init_irq_default_affinity(void)
41 {
42 	if (!cpumask_available(irq_default_affinity))
43 		zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
44 	if (cpumask_empty(irq_default_affinity))
45 		cpumask_setall(irq_default_affinity);
46 }
47 #else
48 static void __init init_irq_default_affinity(void)
49 {
50 }
51 #endif
52 
53 #ifdef CONFIG_SMP
54 static int alloc_masks(struct irq_desc *desc, int node)
55 {
56 	if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
57 				     GFP_KERNEL, node))
58 		return -ENOMEM;
59 
60 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
61 	if (!zalloc_cpumask_var_node(&desc->irq_common_data.effective_affinity,
62 				     GFP_KERNEL, node)) {
63 		free_cpumask_var(desc->irq_common_data.affinity);
64 		return -ENOMEM;
65 	}
66 #endif
67 
68 #ifdef CONFIG_GENERIC_PENDING_IRQ
69 	if (!zalloc_cpumask_var_node(&desc->pending_mask, GFP_KERNEL, node)) {
70 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
71 		free_cpumask_var(desc->irq_common_data.effective_affinity);
72 #endif
73 		free_cpumask_var(desc->irq_common_data.affinity);
74 		return -ENOMEM;
75 	}
76 #endif
77 	return 0;
78 }
79 
80 static void desc_smp_init(struct irq_desc *desc, int node,
81 			  const struct cpumask *affinity)
82 {
83 	if (!affinity)
84 		affinity = irq_default_affinity;
85 	cpumask_copy(desc->irq_common_data.affinity, affinity);
86 
87 #ifdef CONFIG_GENERIC_PENDING_IRQ
88 	cpumask_clear(desc->pending_mask);
89 #endif
90 #ifdef CONFIG_NUMA
91 	desc->irq_common_data.node = node;
92 #endif
93 }
94 
95 static void free_masks(struct irq_desc *desc)
96 {
97 #ifdef CONFIG_GENERIC_PENDING_IRQ
98 	free_cpumask_var(desc->pending_mask);
99 #endif
100 	free_cpumask_var(desc->irq_common_data.affinity);
101 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
102 	free_cpumask_var(desc->irq_common_data.effective_affinity);
103 #endif
104 }
105 
106 #else
107 static inline int
108 alloc_masks(struct irq_desc *desc, int node) { return 0; }
109 static inline void
110 desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
111 static inline void free_masks(struct irq_desc *desc) { }
112 #endif
113 
114 static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
115 			      const struct cpumask *affinity, struct module *owner)
116 {
117 	int cpu;
118 
119 	desc->irq_common_data.handler_data = NULL;
120 	desc->irq_common_data.msi_desc = NULL;
121 
122 	desc->irq_data.common = &desc->irq_common_data;
123 	desc->irq_data.irq = irq;
124 	desc->irq_data.chip = &no_irq_chip;
125 	desc->irq_data.chip_data = NULL;
126 	irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
127 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
128 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
129 	desc->handle_irq = handle_bad_irq;
130 	desc->depth = 1;
131 	desc->irq_count = 0;
132 	desc->irqs_unhandled = 0;
133 	desc->tot_count = 0;
134 	desc->name = NULL;
135 	desc->owner = owner;
136 	for_each_possible_cpu(cpu)
137 		*per_cpu_ptr(desc->kstat_irqs, cpu) = (struct irqstat) { };
138 	desc_smp_init(desc, node, affinity);
139 }
140 
141 int nr_irqs = NR_IRQS;
142 EXPORT_SYMBOL_GPL(nr_irqs);
143 
144 static DEFINE_MUTEX(sparse_irq_lock);
145 static struct maple_tree sparse_irqs = MTREE_INIT_EXT(sparse_irqs,
146 					MT_FLAGS_ALLOC_RANGE |
147 					MT_FLAGS_LOCK_EXTERN |
148 					MT_FLAGS_USE_RCU,
149 					sparse_irq_lock);
150 
151 static int irq_find_free_area(unsigned int from, unsigned int cnt)
152 {
153 	MA_STATE(mas, &sparse_irqs, 0, 0);
154 
155 	if (mas_empty_area(&mas, from, MAX_SPARSE_IRQS, cnt))
156 		return -ENOSPC;
157 	return mas.index;
158 }
159 
160 static unsigned int irq_find_at_or_after(unsigned int offset)
161 {
162 	unsigned long index = offset;
163 	struct irq_desc *desc;
164 
165 	guard(rcu)();
166 	desc = mt_find(&sparse_irqs, &index, nr_irqs);
167 
168 	return desc ? irq_desc_get_irq(desc) : nr_irqs;
169 }
170 
171 static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
172 {
173 	MA_STATE(mas, &sparse_irqs, irq, irq);
174 	WARN_ON(mas_store_gfp(&mas, desc, GFP_KERNEL) != 0);
175 }
176 
177 static void delete_irq_desc(unsigned int irq)
178 {
179 	MA_STATE(mas, &sparse_irqs, irq, irq);
180 	mas_erase(&mas);
181 }
182 
183 #ifdef CONFIG_SPARSE_IRQ
184 static const struct kobj_type irq_kobj_type;
185 #endif
186 
187 static int init_desc(struct irq_desc *desc, int irq, int node,
188 		     unsigned int flags,
189 		     const struct cpumask *affinity,
190 		     struct module *owner)
191 {
192 	desc->kstat_irqs = alloc_percpu(struct irqstat);
193 	if (!desc->kstat_irqs)
194 		return -ENOMEM;
195 
196 	if (alloc_masks(desc, node)) {
197 		free_percpu(desc->kstat_irqs);
198 		return -ENOMEM;
199 	}
200 
201 	raw_spin_lock_init(&desc->lock);
202 	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
203 	mutex_init(&desc->request_mutex);
204 	init_waitqueue_head(&desc->wait_for_threads);
205 	desc_set_defaults(irq, desc, node, affinity, owner);
206 	irqd_set(&desc->irq_data, flags);
207 	irq_resend_init(desc);
208 #ifdef CONFIG_SPARSE_IRQ
209 	kobject_init(&desc->kobj, &irq_kobj_type);
210 	init_rcu_head(&desc->rcu);
211 #endif
212 
213 	return 0;
214 }
215 
216 #ifdef CONFIG_SPARSE_IRQ
217 
218 static void irq_kobj_release(struct kobject *kobj);
219 
220 #ifdef CONFIG_SYSFS
221 static struct kobject *irq_kobj_base;
222 
223 #define IRQ_ATTR_RO(_name) \
224 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
225 
226 static ssize_t per_cpu_count_show(struct kobject *kobj,
227 				  struct kobj_attribute *attr, char *buf)
228 {
229 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
230 	ssize_t ret = 0;
231 	char *p = "";
232 	int cpu;
233 
234 	for_each_possible_cpu(cpu) {
235 		unsigned int c = irq_desc_kstat_cpu(desc, cpu);
236 
237 		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
238 		p = ",";
239 	}
240 
241 	ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
242 	return ret;
243 }
244 IRQ_ATTR_RO(per_cpu_count);
245 
246 static ssize_t chip_name_show(struct kobject *kobj,
247 			      struct kobj_attribute *attr, char *buf)
248 {
249 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
250 	ssize_t ret = 0;
251 
252 	raw_spin_lock_irq(&desc->lock);
253 	if (desc->irq_data.chip && desc->irq_data.chip->name) {
254 		ret = scnprintf(buf, PAGE_SIZE, "%s\n",
255 				desc->irq_data.chip->name);
256 	}
257 	raw_spin_unlock_irq(&desc->lock);
258 
259 	return ret;
260 }
261 IRQ_ATTR_RO(chip_name);
262 
263 static ssize_t hwirq_show(struct kobject *kobj,
264 			  struct kobj_attribute *attr, char *buf)
265 {
266 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
267 	ssize_t ret = 0;
268 
269 	raw_spin_lock_irq(&desc->lock);
270 	if (desc->irq_data.domain)
271 		ret = sprintf(buf, "%lu\n", desc->irq_data.hwirq);
272 	raw_spin_unlock_irq(&desc->lock);
273 
274 	return ret;
275 }
276 IRQ_ATTR_RO(hwirq);
277 
278 static ssize_t type_show(struct kobject *kobj,
279 			 struct kobj_attribute *attr, char *buf)
280 {
281 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
282 	ssize_t ret = 0;
283 
284 	raw_spin_lock_irq(&desc->lock);
285 	ret = sprintf(buf, "%s\n",
286 		      irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
287 	raw_spin_unlock_irq(&desc->lock);
288 
289 	return ret;
290 
291 }
292 IRQ_ATTR_RO(type);
293 
294 static ssize_t wakeup_show(struct kobject *kobj,
295 			   struct kobj_attribute *attr, char *buf)
296 {
297 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
298 	ssize_t ret = 0;
299 
300 	raw_spin_lock_irq(&desc->lock);
301 	ret = sprintf(buf, "%s\n",
302 		      irqd_is_wakeup_set(&desc->irq_data) ? "enabled" : "disabled");
303 	raw_spin_unlock_irq(&desc->lock);
304 
305 	return ret;
306 
307 }
308 IRQ_ATTR_RO(wakeup);
309 
310 static ssize_t name_show(struct kobject *kobj,
311 			 struct kobj_attribute *attr, char *buf)
312 {
313 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
314 	ssize_t ret = 0;
315 
316 	raw_spin_lock_irq(&desc->lock);
317 	if (desc->name)
318 		ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
319 	raw_spin_unlock_irq(&desc->lock);
320 
321 	return ret;
322 }
323 IRQ_ATTR_RO(name);
324 
325 static ssize_t actions_show(struct kobject *kobj,
326 			    struct kobj_attribute *attr, char *buf)
327 {
328 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
329 	struct irqaction *action;
330 	ssize_t ret = 0;
331 	char *p = "";
332 
333 	raw_spin_lock_irq(&desc->lock);
334 	for_each_action_of_desc(desc, action) {
335 		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
336 				 p, action->name);
337 		p = ",";
338 	}
339 	raw_spin_unlock_irq(&desc->lock);
340 
341 	if (ret)
342 		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
343 
344 	return ret;
345 }
346 IRQ_ATTR_RO(actions);
347 
348 static struct attribute *irq_attrs[] = {
349 	&per_cpu_count_attr.attr,
350 	&chip_name_attr.attr,
351 	&hwirq_attr.attr,
352 	&type_attr.attr,
353 	&wakeup_attr.attr,
354 	&name_attr.attr,
355 	&actions_attr.attr,
356 	NULL
357 };
358 ATTRIBUTE_GROUPS(irq);
359 
360 static const struct kobj_type irq_kobj_type = {
361 	.release	= irq_kobj_release,
362 	.sysfs_ops	= &kobj_sysfs_ops,
363 	.default_groups = irq_groups,
364 };
365 
366 static void irq_sysfs_add(int irq, struct irq_desc *desc)
367 {
368 	if (irq_kobj_base) {
369 		/*
370 		 * Continue even in case of failure as this is nothing
371 		 * crucial and failures in the late irq_sysfs_init()
372 		 * cannot be rolled back.
373 		 */
374 		if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
375 			pr_warn("Failed to add kobject for irq %d\n", irq);
376 		else
377 			desc->istate |= IRQS_SYSFS;
378 	}
379 }
380 
381 static void irq_sysfs_del(struct irq_desc *desc)
382 {
383 	/*
384 	 * Only invoke kobject_del() when kobject_add() was successfully
385 	 * invoked for the descriptor. This covers both early boot, where
386 	 * sysfs is not initialized yet, and the case of a failed
387 	 * kobject_add() invocation.
388 	 */
389 	if (desc->istate & IRQS_SYSFS)
390 		kobject_del(&desc->kobj);
391 }
392 
393 static int __init irq_sysfs_init(void)
394 {
395 	struct irq_desc *desc;
396 	int irq;
397 
398 	/* Prevent concurrent irq alloc/free */
399 	irq_lock_sparse();
400 
401 	irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
402 	if (!irq_kobj_base) {
403 		irq_unlock_sparse();
404 		return -ENOMEM;
405 	}
406 
407 	/* Add the already allocated interrupts */
408 	for_each_irq_desc(irq, desc)
409 		irq_sysfs_add(irq, desc);
410 	irq_unlock_sparse();
411 
412 	return 0;
413 }
414 postcore_initcall(irq_sysfs_init);
415 
416 #else /* !CONFIG_SYSFS */
417 
418 static const struct kobj_type irq_kobj_type = {
419 	.release	= irq_kobj_release,
420 };
421 
422 static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
423 static void irq_sysfs_del(struct irq_desc *desc) {}
424 
425 #endif /* CONFIG_SYSFS */
426 
427 struct irq_desc *irq_to_desc(unsigned int irq)
428 {
429 	return mtree_load(&sparse_irqs, irq);
430 }
431 #ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
432 EXPORT_SYMBOL_GPL(irq_to_desc);
433 #endif
434 
435 void irq_lock_sparse(void)
436 {
437 	mutex_lock(&sparse_irq_lock);
438 }
439 
440 void irq_unlock_sparse(void)
441 {
442 	mutex_unlock(&sparse_irq_lock);
443 }
444 
445 static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
446 				   const struct cpumask *affinity,
447 				   struct module *owner)
448 {
449 	struct irq_desc *desc;
450 	int ret;
451 
452 	desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
453 	if (!desc)
454 		return NULL;
455 
456 	ret = init_desc(desc, irq, node, flags, affinity, owner);
457 	if (unlikely(ret)) {
458 		kfree(desc);
459 		return NULL;
460 	}
461 
462 	return desc;
463 }
464 
465 static void irq_kobj_release(struct kobject *kobj)
466 {
467 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
468 
469 	free_masks(desc);
470 	free_percpu(desc->kstat_irqs);
471 	kfree(desc);
472 }
473 
474 static void delayed_free_desc(struct rcu_head *rhp)
475 {
476 	struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
477 
478 	kobject_put(&desc->kobj);
479 }
480 
481 static void free_desc(unsigned int irq)
482 {
483 	struct irq_desc *desc = irq_to_desc(irq);
484 
485 	irq_remove_debugfs_entry(desc);
486 	unregister_irq_proc(irq, desc);
487 
488 	/*
489 	 * sparse_irq_lock protects also show_interrupts() and
490 	 * kstat_irq_usr(). Once we deleted the descriptor from the
491 	 * sparse tree we can free it. Access in proc will fail to
492 	 * lookup the descriptor.
493 	 *
494 	 * The sysfs entry must be serialized against a concurrent
495 	 * irq_sysfs_init() as well.
496 	 */
497 	irq_sysfs_del(desc);
498 	delete_irq_desc(irq);
499 
500 	/*
501 	 * We free the descriptor, masks and stat fields via RCU. That
502 	 * allows demultiplex interrupts to do rcu based management of
503 	 * the child interrupts.
504 	 * This also allows us to use rcu in kstat_irqs_usr().
505 	 */
506 	call_rcu(&desc->rcu, delayed_free_desc);
507 }
508 
509 static int alloc_descs(unsigned int start, unsigned int cnt, int node,
510 		       const struct irq_affinity_desc *affinity,
511 		       struct module *owner)
512 {
513 	struct irq_desc *desc;
514 	int i;
515 
516 	/* Validate affinity mask(s) */
517 	if (affinity) {
518 		for (i = 0; i < cnt; i++) {
519 			if (cpumask_empty(&affinity[i].mask))
520 				return -EINVAL;
521 		}
522 	}
523 
524 	for (i = 0; i < cnt; i++) {
525 		const struct cpumask *mask = NULL;
526 		unsigned int flags = 0;
527 
528 		if (affinity) {
529 			if (affinity->is_managed) {
530 				flags = IRQD_AFFINITY_MANAGED |
531 					IRQD_MANAGED_SHUTDOWN;
532 			}
533 			mask = &affinity->mask;
534 			node = cpu_to_node(cpumask_first(mask));
535 			affinity++;
536 		}
537 
538 		desc = alloc_desc(start + i, node, flags, mask, owner);
539 		if (!desc)
540 			goto err;
541 		irq_insert_desc(start + i, desc);
542 		irq_sysfs_add(start + i, desc);
543 		irq_add_debugfs_entry(start + i, desc);
544 	}
545 	return start;
546 
547 err:
548 	for (i--; i >= 0; i--)
549 		free_desc(start + i);
550 	return -ENOMEM;
551 }
552 
553 static int irq_expand_nr_irqs(unsigned int nr)
554 {
555 	if (nr > MAX_SPARSE_IRQS)
556 		return -ENOMEM;
557 	nr_irqs = nr;
558 	return 0;
559 }
560 
561 int __init early_irq_init(void)
562 {
563 	int i, initcnt, node = first_online_node;
564 	struct irq_desc *desc;
565 
566 	init_irq_default_affinity();
567 
568 	/* Let arch update nr_irqs and return the nr of preallocated irqs */
569 	initcnt = arch_probe_nr_irqs();
570 	printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
571 	       NR_IRQS, nr_irqs, initcnt);
572 
573 	if (WARN_ON(nr_irqs > MAX_SPARSE_IRQS))
574 		nr_irqs = MAX_SPARSE_IRQS;
575 
576 	if (WARN_ON(initcnt > MAX_SPARSE_IRQS))
577 		initcnt = MAX_SPARSE_IRQS;
578 
579 	if (initcnt > nr_irqs)
580 		nr_irqs = initcnt;
581 
582 	for (i = 0; i < initcnt; i++) {
583 		desc = alloc_desc(i, node, 0, NULL, NULL);
584 		irq_insert_desc(i, desc);
585 	}
586 	return arch_early_irq_init();
587 }
588 
589 #else /* !CONFIG_SPARSE_IRQ */
590 
591 struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
592 	[0 ... NR_IRQS-1] = {
593 		.handle_irq	= handle_bad_irq,
594 		.depth		= 1,
595 		.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
596 	}
597 };
598 
599 int __init early_irq_init(void)
600 {
601 	int count, i, node = first_online_node;
602 	int ret;
603 
604 	init_irq_default_affinity();
605 
606 	printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
607 
608 	count = ARRAY_SIZE(irq_desc);
609 
610 	for (i = 0; i < count; i++) {
611 		ret = init_desc(irq_desc + i, i, node, 0, NULL, NULL);
612 		if (unlikely(ret))
613 			goto __free_desc_res;
614 	}
615 
616 	return arch_early_irq_init();
617 
618 __free_desc_res:
619 	while (--i >= 0) {
620 		free_masks(irq_desc + i);
621 		free_percpu(irq_desc[i].kstat_irqs);
622 	}
623 
624 	return ret;
625 }
626 
627 struct irq_desc *irq_to_desc(unsigned int irq)
628 {
629 	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
630 }
631 EXPORT_SYMBOL(irq_to_desc);
632 
633 static void free_desc(unsigned int irq)
634 {
635 	struct irq_desc *desc = irq_to_desc(irq);
636 	unsigned long flags;
637 
638 	raw_spin_lock_irqsave(&desc->lock, flags);
639 	desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
640 	raw_spin_unlock_irqrestore(&desc->lock, flags);
641 	delete_irq_desc(irq);
642 }
643 
644 static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
645 			      const struct irq_affinity_desc *affinity,
646 			      struct module *owner)
647 {
648 	u32 i;
649 
650 	for (i = 0; i < cnt; i++) {
651 		struct irq_desc *desc = irq_to_desc(start + i);
652 
653 		desc->owner = owner;
654 		irq_insert_desc(start + i, desc);
655 	}
656 	return start;
657 }
658 
659 static int irq_expand_nr_irqs(unsigned int nr)
660 {
661 	return -ENOMEM;
662 }
663 
664 void irq_mark_irq(unsigned int irq)
665 {
666 	mutex_lock(&sparse_irq_lock);
667 	irq_insert_desc(irq, irq_desc + irq);
668 	mutex_unlock(&sparse_irq_lock);
669 }
670 
671 #ifdef CONFIG_GENERIC_IRQ_LEGACY
672 void irq_init_desc(unsigned int irq)
673 {
674 	free_desc(irq);
675 }
676 #endif
677 
678 #endif /* !CONFIG_SPARSE_IRQ */
679 
680 int handle_irq_desc(struct irq_desc *desc)
681 {
682 	struct irq_data *data;
683 
684 	if (!desc)
685 		return -EINVAL;
686 
687 	data = irq_desc_get_irq_data(desc);
688 	if (WARN_ON_ONCE(!in_hardirq() && handle_enforce_irqctx(data)))
689 		return -EPERM;
690 
691 	generic_handle_irq_desc(desc);
692 	return 0;
693 }
694 
695 /**
696  * generic_handle_irq - Invoke the handler for a particular irq
697  * @irq:	The irq number to handle
698  *
699  * Returns:	0 on success, or -EINVAL if conversion has failed
700  *
701  * 		This function must be called from an IRQ context with irq regs
702  * 		initialized.
703   */
704 int generic_handle_irq(unsigned int irq)
705 {
706 	return handle_irq_desc(irq_to_desc(irq));
707 }
708 EXPORT_SYMBOL_GPL(generic_handle_irq);
709 
710 /**
711  * generic_handle_irq_safe - Invoke the handler for a particular irq from any
712  *			     context.
713  * @irq:	The irq number to handle
714  *
715  * Returns:	0 on success, a negative value on error.
716  *
717  * This function can be called from any context (IRQ or process context). It
718  * will report an error if not invoked from IRQ context and the irq has been
719  * marked to enforce IRQ-context only.
720  */
721 int generic_handle_irq_safe(unsigned int irq)
722 {
723 	unsigned long flags;
724 	int ret;
725 
726 	local_irq_save(flags);
727 	ret = handle_irq_desc(irq_to_desc(irq));
728 	local_irq_restore(flags);
729 	return ret;
730 }
731 EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
732 
733 #ifdef CONFIG_IRQ_DOMAIN
734 /**
735  * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
736  *                             to a domain.
737  * @domain:	The domain where to perform the lookup
738  * @hwirq:	The HW irq number to convert to a logical one
739  *
740  * Returns:	0 on success, or -EINVAL if conversion has failed
741  *
742  * 		This function must be called from an IRQ context with irq regs
743  * 		initialized.
744  */
745 int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
746 {
747 	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
748 }
749 EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
750 
751  /**
752  * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
753  *			     to a domain from any context.
754  * @domain:	The domain where to perform the lookup
755  * @hwirq:	The HW irq number to convert to a logical one
756  *
757  * Returns:	0 on success, a negative value on error.
758  *
759  * This function can be called from any context (IRQ or process
760  * context). If the interrupt is marked as 'enforce IRQ-context only' then
761  * the function must be invoked from hard interrupt context.
762  */
763 int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
764 {
765 	unsigned long flags;
766 	int ret;
767 
768 	local_irq_save(flags);
769 	ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
770 	local_irq_restore(flags);
771 	return ret;
772 }
773 EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
774 
775 /**
776  * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
777  *                             to a domain.
778  * @domain:	The domain where to perform the lookup
779  * @hwirq:	The HW irq number to convert to a logical one
780  *
781  * Returns:	0 on success, or -EINVAL if conversion has failed
782  *
783  * 		This function must be called from an NMI context with irq regs
784  * 		initialized.
785  **/
786 int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq)
787 {
788 	WARN_ON_ONCE(!in_nmi());
789 	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
790 }
791 #endif
792 
793 /* Dynamic interrupt handling */
794 
795 /**
796  * irq_free_descs - free irq descriptors
797  * @from:	Start of descriptor range
798  * @cnt:	Number of consecutive irqs to free
799  */
800 void irq_free_descs(unsigned int from, unsigned int cnt)
801 {
802 	int i;
803 
804 	if (from >= nr_irqs || (from + cnt) > nr_irqs)
805 		return;
806 
807 	mutex_lock(&sparse_irq_lock);
808 	for (i = 0; i < cnt; i++)
809 		free_desc(from + i);
810 
811 	mutex_unlock(&sparse_irq_lock);
812 }
813 EXPORT_SYMBOL_GPL(irq_free_descs);
814 
815 /**
816  * __irq_alloc_descs - allocate and initialize a range of irq descriptors
817  * @irq:	Allocate for specific irq number if irq >= 0
818  * @from:	Start the search from this irq number
819  * @cnt:	Number of consecutive irqs to allocate.
820  * @node:	Preferred node on which the irq descriptor should be allocated
821  * @owner:	Owning module (can be NULL)
822  * @affinity:	Optional pointer to an affinity mask array of size @cnt which
823  *		hints where the irq descriptors should be allocated and which
824  *		default affinities to use
825  *
826  * Returns the first irq number or error code
827  */
828 int __ref
829 __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
830 		  struct module *owner, const struct irq_affinity_desc *affinity)
831 {
832 	int start, ret;
833 
834 	if (!cnt)
835 		return -EINVAL;
836 
837 	if (irq >= 0) {
838 		if (from > irq)
839 			return -EINVAL;
840 		from = irq;
841 	} else {
842 		/*
843 		 * For interrupts which are freely allocated the
844 		 * architecture can force a lower bound to the @from
845 		 * argument. x86 uses this to exclude the GSI space.
846 		 */
847 		from = arch_dynirq_lower_bound(from);
848 	}
849 
850 	mutex_lock(&sparse_irq_lock);
851 
852 	start = irq_find_free_area(from, cnt);
853 	ret = -EEXIST;
854 	if (irq >=0 && start != irq)
855 		goto unlock;
856 
857 	if (start + cnt > nr_irqs) {
858 		ret = irq_expand_nr_irqs(start + cnt);
859 		if (ret)
860 			goto unlock;
861 	}
862 	ret = alloc_descs(start, cnt, node, affinity, owner);
863 unlock:
864 	mutex_unlock(&sparse_irq_lock);
865 	return ret;
866 }
867 EXPORT_SYMBOL_GPL(__irq_alloc_descs);
868 
869 /**
870  * irq_get_next_irq - get next allocated irq number
871  * @offset:	where to start the search
872  *
873  * Returns next irq number after offset or nr_irqs if none is found.
874  */
875 unsigned int irq_get_next_irq(unsigned int offset)
876 {
877 	return irq_find_at_or_after(offset);
878 }
879 
880 struct irq_desc *
881 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
882 		    unsigned int check)
883 {
884 	struct irq_desc *desc = irq_to_desc(irq);
885 
886 	if (desc) {
887 		if (check & _IRQ_DESC_CHECK) {
888 			if ((check & _IRQ_DESC_PERCPU) &&
889 			    !irq_settings_is_per_cpu_devid(desc))
890 				return NULL;
891 
892 			if (!(check & _IRQ_DESC_PERCPU) &&
893 			    irq_settings_is_per_cpu_devid(desc))
894 				return NULL;
895 		}
896 
897 		if (bus)
898 			chip_bus_lock(desc);
899 		raw_spin_lock_irqsave(&desc->lock, *flags);
900 	}
901 	return desc;
902 }
903 
904 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
905 	__releases(&desc->lock)
906 {
907 	raw_spin_unlock_irqrestore(&desc->lock, flags);
908 	if (bus)
909 		chip_bus_sync_unlock(desc);
910 }
911 
912 int irq_set_percpu_devid_partition(unsigned int irq,
913 				   const struct cpumask *affinity)
914 {
915 	struct irq_desc *desc = irq_to_desc(irq);
916 
917 	if (!desc || 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 	desc->percpu_affinity = affinity ? : cpu_possible_mask;
926 
927 	irq_set_percpu_devid_flags(irq);
928 	return 0;
929 }
930 
931 int irq_set_percpu_devid(unsigned int irq)
932 {
933 	return irq_set_percpu_devid_partition(irq, NULL);
934 }
935 
936 int irq_get_percpu_devid_partition(unsigned int irq, 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 	if (affinity)
944 		cpumask_copy(affinity, desc->percpu_affinity);
945 
946 	return 0;
947 }
948 EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
949 
950 void kstat_incr_irq_this_cpu(unsigned int irq)
951 {
952 	kstat_incr_irqs_this_cpu(irq_to_desc(irq));
953 }
954 
955 /**
956  * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
957  * @irq:	The interrupt number
958  * @cpu:	The cpu number
959  *
960  * Returns the sum of interrupt counts on @cpu since boot for
961  * @irq. The caller must ensure that the interrupt is not removed
962  * concurrently.
963  */
964 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
965 {
966 	struct irq_desc *desc = irq_to_desc(irq);
967 
968 	return desc && desc->kstat_irqs ? per_cpu(desc->kstat_irqs->cnt, cpu) : 0;
969 }
970 
971 unsigned int kstat_irqs_desc(struct irq_desc *desc, const struct cpumask *cpumask)
972 {
973 	unsigned int sum = 0;
974 	int cpu;
975 
976 	if (!irq_settings_is_per_cpu_devid(desc) &&
977 	    !irq_settings_is_per_cpu(desc) &&
978 	    !irq_is_nmi(desc))
979 		return data_race(desc->tot_count);
980 
981 	for_each_cpu(cpu, cpumask)
982 		sum += data_race(per_cpu(desc->kstat_irqs->cnt, cpu));
983 	return sum;
984 }
985 
986 static unsigned int kstat_irqs(unsigned int irq)
987 {
988 	struct irq_desc *desc = irq_to_desc(irq);
989 
990 	if (!desc || !desc->kstat_irqs)
991 		return 0;
992 	return kstat_irqs_desc(desc, cpu_possible_mask);
993 }
994 
995 #ifdef CONFIG_GENERIC_IRQ_STAT_SNAPSHOT
996 
997 void kstat_snapshot_irqs(void)
998 {
999 	struct irq_desc *desc;
1000 	unsigned int irq;
1001 
1002 	for_each_irq_desc(irq, desc) {
1003 		if (!desc->kstat_irqs)
1004 			continue;
1005 		this_cpu_write(desc->kstat_irqs->ref, this_cpu_read(desc->kstat_irqs->cnt));
1006 	}
1007 }
1008 
1009 unsigned int kstat_get_irq_since_snapshot(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 this_cpu_read(desc->kstat_irqs->cnt) - this_cpu_read(desc->kstat_irqs->ref);
1016 }
1017 
1018 #endif
1019 
1020 /**
1021  * kstat_irqs_usr - Get the statistics for an interrupt from thread context
1022  * @irq:	The interrupt number
1023  *
1024  * Returns the sum of interrupt counts on all cpus since boot for @irq.
1025  *
1026  * It uses rcu to protect the access since a concurrent removal of an
1027  * interrupt descriptor is observing an rcu grace period before
1028  * delayed_free_desc()/irq_kobj_release().
1029  */
1030 unsigned int kstat_irqs_usr(unsigned int irq)
1031 {
1032 	unsigned int sum;
1033 
1034 	rcu_read_lock();
1035 	sum = kstat_irqs(irq);
1036 	rcu_read_unlock();
1037 	return sum;
1038 }
1039 
1040 #ifdef CONFIG_LOCKDEP
1041 void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
1042 			     struct lock_class_key *request_class)
1043 {
1044 	struct irq_desc *desc = irq_to_desc(irq);
1045 
1046 	if (desc) {
1047 		lockdep_set_class(&desc->lock, lock_class);
1048 		lockdep_set_class(&desc->request_mutex, request_class);
1049 	}
1050 }
1051 EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1052 #endif
1053