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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
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