Loading...
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
95#else
96static inline int
97alloc_masks(struct irq_desc *desc, int node) { return 0; }
98static inline void
99desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
100#endif
101
102static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
103 const struct cpumask *affinity, struct module *owner)
104{
105 int cpu;
106
107 desc->irq_common_data.handler_data = NULL;
108 desc->irq_common_data.msi_desc = NULL;
109
110 desc->irq_data.common = &desc->irq_common_data;
111 desc->irq_data.irq = irq;
112 desc->irq_data.chip = &no_irq_chip;
113 desc->irq_data.chip_data = NULL;
114 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
115 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
116 irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
117 desc->handle_irq = handle_bad_irq;
118 desc->depth = 1;
119 desc->irq_count = 0;
120 desc->irqs_unhandled = 0;
121 desc->tot_count = 0;
122 desc->name = NULL;
123 desc->owner = owner;
124 for_each_possible_cpu(cpu)
125 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
126 desc_smp_init(desc, node, affinity);
127}
128
129int nr_irqs = NR_IRQS;
130EXPORT_SYMBOL_GPL(nr_irqs);
131
132static DEFINE_MUTEX(sparse_irq_lock);
133static struct maple_tree sparse_irqs = MTREE_INIT_EXT(sparse_irqs,
134 MT_FLAGS_ALLOC_RANGE |
135 MT_FLAGS_LOCK_EXTERN |
136 MT_FLAGS_USE_RCU,
137 sparse_irq_lock);
138
139static int irq_find_free_area(unsigned int from, unsigned int cnt)
140{
141 MA_STATE(mas, &sparse_irqs, 0, 0);
142
143 if (mas_empty_area(&mas, from, MAX_SPARSE_IRQS, cnt))
144 return -ENOSPC;
145 return mas.index;
146}
147
148static unsigned int irq_find_at_or_after(unsigned int offset)
149{
150 unsigned long index = offset;
151 struct irq_desc *desc = mt_find(&sparse_irqs, &index, nr_irqs);
152
153 return desc ? irq_desc_get_irq(desc) : nr_irqs;
154}
155
156static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
157{
158 MA_STATE(mas, &sparse_irqs, irq, irq);
159 WARN_ON(mas_store_gfp(&mas, desc, GFP_KERNEL) != 0);
160}
161
162static void delete_irq_desc(unsigned int irq)
163{
164 MA_STATE(mas, &sparse_irqs, irq, irq);
165 mas_erase(&mas);
166}
167
168#ifdef CONFIG_SPARSE_IRQ
169
170static void irq_kobj_release(struct kobject *kobj);
171
172#ifdef CONFIG_SYSFS
173static struct kobject *irq_kobj_base;
174
175#define IRQ_ATTR_RO(_name) \
176static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
177
178static ssize_t per_cpu_count_show(struct kobject *kobj,
179 struct kobj_attribute *attr, char *buf)
180{
181 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
182 ssize_t ret = 0;
183 char *p = "";
184 int cpu;
185
186 for_each_possible_cpu(cpu) {
187 unsigned int c = irq_desc_kstat_cpu(desc, cpu);
188
189 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
190 p = ",";
191 }
192
193 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
194 return ret;
195}
196IRQ_ATTR_RO(per_cpu_count);
197
198static ssize_t chip_name_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 if (desc->irq_data.chip && desc->irq_data.chip->name) {
206 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
207 desc->irq_data.chip->name);
208 }
209 raw_spin_unlock_irq(&desc->lock);
210
211 return ret;
212}
213IRQ_ATTR_RO(chip_name);
214
215static ssize_t hwirq_show(struct kobject *kobj,
216 struct kobj_attribute *attr, char *buf)
217{
218 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
219 ssize_t ret = 0;
220
221 raw_spin_lock_irq(&desc->lock);
222 if (desc->irq_data.domain)
223 ret = sprintf(buf, "%lu\n", desc->irq_data.hwirq);
224 raw_spin_unlock_irq(&desc->lock);
225
226 return ret;
227}
228IRQ_ATTR_RO(hwirq);
229
230static ssize_t type_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 ret = sprintf(buf, "%s\n",
238 irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
239 raw_spin_unlock_irq(&desc->lock);
240
241 return ret;
242
243}
244IRQ_ATTR_RO(type);
245
246static ssize_t wakeup_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 ret = sprintf(buf, "%s\n",
254 irqd_is_wakeup_set(&desc->irq_data) ? "enabled" : "disabled");
255 raw_spin_unlock_irq(&desc->lock);
256
257 return ret;
258
259}
260IRQ_ATTR_RO(wakeup);
261
262static ssize_t name_show(struct kobject *kobj,
263 struct kobj_attribute *attr, char *buf)
264{
265 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
266 ssize_t ret = 0;
267
268 raw_spin_lock_irq(&desc->lock);
269 if (desc->name)
270 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
271 raw_spin_unlock_irq(&desc->lock);
272
273 return ret;
274}
275IRQ_ATTR_RO(name);
276
277static ssize_t actions_show(struct kobject *kobj,
278 struct kobj_attribute *attr, char *buf)
279{
280 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
281 struct irqaction *action;
282 ssize_t ret = 0;
283 char *p = "";
284
285 raw_spin_lock_irq(&desc->lock);
286 for_each_action_of_desc(desc, action) {
287 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
288 p, action->name);
289 p = ",";
290 }
291 raw_spin_unlock_irq(&desc->lock);
292
293 if (ret)
294 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
295
296 return ret;
297}
298IRQ_ATTR_RO(actions);
299
300static struct attribute *irq_attrs[] = {
301 &per_cpu_count_attr.attr,
302 &chip_name_attr.attr,
303 &hwirq_attr.attr,
304 &type_attr.attr,
305 &wakeup_attr.attr,
306 &name_attr.attr,
307 &actions_attr.attr,
308 NULL
309};
310ATTRIBUTE_GROUPS(irq);
311
312static const struct kobj_type irq_kobj_type = {
313 .release = irq_kobj_release,
314 .sysfs_ops = &kobj_sysfs_ops,
315 .default_groups = irq_groups,
316};
317
318static void irq_sysfs_add(int irq, struct irq_desc *desc)
319{
320 if (irq_kobj_base) {
321 /*
322 * Continue even in case of failure as this is nothing
323 * crucial and failures in the late irq_sysfs_init()
324 * cannot be rolled back.
325 */
326 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
327 pr_warn("Failed to add kobject for irq %d\n", irq);
328 else
329 desc->istate |= IRQS_SYSFS;
330 }
331}
332
333static void irq_sysfs_del(struct irq_desc *desc)
334{
335 /*
336 * Only invoke kobject_del() when kobject_add() was successfully
337 * invoked for the descriptor. This covers both early boot, where
338 * sysfs is not initialized yet, and the case of a failed
339 * kobject_add() invocation.
340 */
341 if (desc->istate & IRQS_SYSFS)
342 kobject_del(&desc->kobj);
343}
344
345static int __init irq_sysfs_init(void)
346{
347 struct irq_desc *desc;
348 int irq;
349
350 /* Prevent concurrent irq alloc/free */
351 irq_lock_sparse();
352
353 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
354 if (!irq_kobj_base) {
355 irq_unlock_sparse();
356 return -ENOMEM;
357 }
358
359 /* Add the already allocated interrupts */
360 for_each_irq_desc(irq, desc)
361 irq_sysfs_add(irq, desc);
362 irq_unlock_sparse();
363
364 return 0;
365}
366postcore_initcall(irq_sysfs_init);
367
368#else /* !CONFIG_SYSFS */
369
370static const struct kobj_type irq_kobj_type = {
371 .release = irq_kobj_release,
372};
373
374static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
375static void irq_sysfs_del(struct irq_desc *desc) {}
376
377#endif /* CONFIG_SYSFS */
378
379struct irq_desc *irq_to_desc(unsigned int irq)
380{
381 return mtree_load(&sparse_irqs, irq);
382}
383#ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
384EXPORT_SYMBOL_GPL(irq_to_desc);
385#endif
386
387#ifdef CONFIG_SMP
388static void free_masks(struct irq_desc *desc)
389{
390#ifdef CONFIG_GENERIC_PENDING_IRQ
391 free_cpumask_var(desc->pending_mask);
392#endif
393 free_cpumask_var(desc->irq_common_data.affinity);
394#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
395 free_cpumask_var(desc->irq_common_data.effective_affinity);
396#endif
397}
398#else
399static inline void free_masks(struct irq_desc *desc) { }
400#endif
401
402void irq_lock_sparse(void)
403{
404 mutex_lock(&sparse_irq_lock);
405}
406
407void irq_unlock_sparse(void)
408{
409 mutex_unlock(&sparse_irq_lock);
410}
411
412static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
413 const struct cpumask *affinity,
414 struct module *owner)
415{
416 struct irq_desc *desc;
417
418 desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
419 if (!desc)
420 return NULL;
421 /* allocate based on nr_cpu_ids */
422 desc->kstat_irqs = alloc_percpu(unsigned int);
423 if (!desc->kstat_irqs)
424 goto err_desc;
425
426 if (alloc_masks(desc, node))
427 goto err_kstat;
428
429 raw_spin_lock_init(&desc->lock);
430 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
431 mutex_init(&desc->request_mutex);
432 init_rcu_head(&desc->rcu);
433 init_waitqueue_head(&desc->wait_for_threads);
434
435 desc_set_defaults(irq, desc, node, affinity, owner);
436 irqd_set(&desc->irq_data, flags);
437 kobject_init(&desc->kobj, &irq_kobj_type);
438 irq_resend_init(desc);
439
440 return desc;
441
442err_kstat:
443 free_percpu(desc->kstat_irqs);
444err_desc:
445 kfree(desc);
446 return NULL;
447}
448
449static void irq_kobj_release(struct kobject *kobj)
450{
451 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
452
453 free_masks(desc);
454 free_percpu(desc->kstat_irqs);
455 kfree(desc);
456}
457
458static void delayed_free_desc(struct rcu_head *rhp)
459{
460 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
461
462 kobject_put(&desc->kobj);
463}
464
465static void free_desc(unsigned int irq)
466{
467 struct irq_desc *desc = irq_to_desc(irq);
468
469 irq_remove_debugfs_entry(desc);
470 unregister_irq_proc(irq, desc);
471
472 /*
473 * sparse_irq_lock protects also show_interrupts() and
474 * kstat_irq_usr(). Once we deleted the descriptor from the
475 * sparse tree we can free it. Access in proc will fail to
476 * lookup the descriptor.
477 *
478 * The sysfs entry must be serialized against a concurrent
479 * irq_sysfs_init() as well.
480 */
481 irq_sysfs_del(desc);
482 delete_irq_desc(irq);
483
484 /*
485 * We free the descriptor, masks and stat fields via RCU. That
486 * allows demultiplex interrupts to do rcu based management of
487 * the child interrupts.
488 * This also allows us to use rcu in kstat_irqs_usr().
489 */
490 call_rcu(&desc->rcu, delayed_free_desc);
491}
492
493static int alloc_descs(unsigned int start, unsigned int cnt, int node,
494 const struct irq_affinity_desc *affinity,
495 struct module *owner)
496{
497 struct irq_desc *desc;
498 int i;
499
500 /* Validate affinity mask(s) */
501 if (affinity) {
502 for (i = 0; i < cnt; i++) {
503 if (cpumask_empty(&affinity[i].mask))
504 return -EINVAL;
505 }
506 }
507
508 for (i = 0; i < cnt; i++) {
509 const struct cpumask *mask = NULL;
510 unsigned int flags = 0;
511
512 if (affinity) {
513 if (affinity->is_managed) {
514 flags = IRQD_AFFINITY_MANAGED |
515 IRQD_MANAGED_SHUTDOWN;
516 }
517 mask = &affinity->mask;
518 node = cpu_to_node(cpumask_first(mask));
519 affinity++;
520 }
521
522 desc = alloc_desc(start + i, node, flags, mask, owner);
523 if (!desc)
524 goto err;
525 irq_insert_desc(start + i, desc);
526 irq_sysfs_add(start + i, desc);
527 irq_add_debugfs_entry(start + i, desc);
528 }
529 return start;
530
531err:
532 for (i--; i >= 0; i--)
533 free_desc(start + i);
534 return -ENOMEM;
535}
536
537static int irq_expand_nr_irqs(unsigned int nr)
538{
539 if (nr > MAX_SPARSE_IRQS)
540 return -ENOMEM;
541 nr_irqs = nr;
542 return 0;
543}
544
545int __init early_irq_init(void)
546{
547 int i, initcnt, node = first_online_node;
548 struct irq_desc *desc;
549
550 init_irq_default_affinity();
551
552 /* Let arch update nr_irqs and return the nr of preallocated irqs */
553 initcnt = arch_probe_nr_irqs();
554 printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
555 NR_IRQS, nr_irqs, initcnt);
556
557 if (WARN_ON(nr_irqs > MAX_SPARSE_IRQS))
558 nr_irqs = MAX_SPARSE_IRQS;
559
560 if (WARN_ON(initcnt > MAX_SPARSE_IRQS))
561 initcnt = MAX_SPARSE_IRQS;
562
563 if (initcnt > nr_irqs)
564 nr_irqs = initcnt;
565
566 for (i = 0; i < initcnt; i++) {
567 desc = alloc_desc(i, node, 0, NULL, NULL);
568 irq_insert_desc(i, desc);
569 }
570 return arch_early_irq_init();
571}
572
573#else /* !CONFIG_SPARSE_IRQ */
574
575struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
576 [0 ... NR_IRQS-1] = {
577 .handle_irq = handle_bad_irq,
578 .depth = 1,
579 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
580 }
581};
582
583int __init early_irq_init(void)
584{
585 int count, i, node = first_online_node;
586 struct irq_desc *desc;
587
588 init_irq_default_affinity();
589
590 printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
591
592 desc = irq_desc;
593 count = ARRAY_SIZE(irq_desc);
594
595 for (i = 0; i < count; i++) {
596 desc[i].kstat_irqs = alloc_percpu(unsigned int);
597 alloc_masks(&desc[i], node);
598 raw_spin_lock_init(&desc[i].lock);
599 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
600 mutex_init(&desc[i].request_mutex);
601 init_waitqueue_head(&desc[i].wait_for_threads);
602 desc_set_defaults(i, &desc[i], node, NULL, NULL);
603 irq_resend_init(&desc[i]);
604 }
605 return arch_early_irq_init();
606}
607
608struct irq_desc *irq_to_desc(unsigned int irq)
609{
610 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
611}
612EXPORT_SYMBOL(irq_to_desc);
613
614static void free_desc(unsigned int irq)
615{
616 struct irq_desc *desc = irq_to_desc(irq);
617 unsigned long flags;
618
619 raw_spin_lock_irqsave(&desc->lock, flags);
620 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
621 raw_spin_unlock_irqrestore(&desc->lock, flags);
622 delete_irq_desc(irq);
623}
624
625static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
626 const struct irq_affinity_desc *affinity,
627 struct module *owner)
628{
629 u32 i;
630
631 for (i = 0; i < cnt; i++) {
632 struct irq_desc *desc = irq_to_desc(start + i);
633
634 desc->owner = owner;
635 irq_insert_desc(start + i, desc);
636 }
637 return start;
638}
639
640static int irq_expand_nr_irqs(unsigned int nr)
641{
642 return -ENOMEM;
643}
644
645void irq_mark_irq(unsigned int irq)
646{
647 mutex_lock(&sparse_irq_lock);
648 irq_insert_desc(irq, irq_desc + irq);
649 mutex_unlock(&sparse_irq_lock);
650}
651
652#ifdef CONFIG_GENERIC_IRQ_LEGACY
653void irq_init_desc(unsigned int irq)
654{
655 free_desc(irq);
656}
657#endif
658
659#endif /* !CONFIG_SPARSE_IRQ */
660
661int handle_irq_desc(struct irq_desc *desc)
662{
663 struct irq_data *data;
664
665 if (!desc)
666 return -EINVAL;
667
668 data = irq_desc_get_irq_data(desc);
669 if (WARN_ON_ONCE(!in_hardirq() && handle_enforce_irqctx(data)))
670 return -EPERM;
671
672 generic_handle_irq_desc(desc);
673 return 0;
674}
675
676/**
677 * generic_handle_irq - Invoke the handler for a particular irq
678 * @irq: The irq number to handle
679 *
680 * Returns: 0 on success, or -EINVAL if conversion has failed
681 *
682 * This function must be called from an IRQ context with irq regs
683 * initialized.
684 */
685int generic_handle_irq(unsigned int irq)
686{
687 return handle_irq_desc(irq_to_desc(irq));
688}
689EXPORT_SYMBOL_GPL(generic_handle_irq);
690
691/**
692 * generic_handle_irq_safe - Invoke the handler for a particular irq from any
693 * context.
694 * @irq: The irq number to handle
695 *
696 * Returns: 0 on success, a negative value on error.
697 *
698 * This function can be called from any context (IRQ or process context). It
699 * will report an error if not invoked from IRQ context and the irq has been
700 * marked to enforce IRQ-context only.
701 */
702int generic_handle_irq_safe(unsigned int irq)
703{
704 unsigned long flags;
705 int ret;
706
707 local_irq_save(flags);
708 ret = handle_irq_desc(irq_to_desc(irq));
709 local_irq_restore(flags);
710 return ret;
711}
712EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
713
714#ifdef CONFIG_IRQ_DOMAIN
715/**
716 * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
717 * to a domain.
718 * @domain: The domain where to perform the lookup
719 * @hwirq: The HW irq number to convert to a logical one
720 *
721 * Returns: 0 on success, or -EINVAL if conversion has failed
722 *
723 * This function must be called from an IRQ context with irq regs
724 * initialized.
725 */
726int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
727{
728 return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
729}
730EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
731
732 /**
733 * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
734 * to a domain from any context.
735 * @domain: The domain where to perform the lookup
736 * @hwirq: The HW irq number to convert to a logical one
737 *
738 * Returns: 0 on success, a negative value on error.
739 *
740 * This function can be called from any context (IRQ or process
741 * context). If the interrupt is marked as 'enforce IRQ-context only' then
742 * the function must be invoked from hard interrupt context.
743 */
744int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
745{
746 unsigned long flags;
747 int ret;
748
749 local_irq_save(flags);
750 ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
751 local_irq_restore(flags);
752 return ret;
753}
754EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
755
756/**
757 * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
758 * to a domain.
759 * @domain: The domain where to perform the lookup
760 * @hwirq: The HW irq number to convert to a logical one
761 *
762 * Returns: 0 on success, or -EINVAL if conversion has failed
763 *
764 * This function must be called from an NMI context with irq regs
765 * initialized.
766 **/
767int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq)
768{
769 WARN_ON_ONCE(!in_nmi());
770 return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
771}
772#endif
773
774/* Dynamic interrupt handling */
775
776/**
777 * irq_free_descs - free irq descriptors
778 * @from: Start of descriptor range
779 * @cnt: Number of consecutive irqs to free
780 */
781void irq_free_descs(unsigned int from, unsigned int cnt)
782{
783 int i;
784
785 if (from >= nr_irqs || (from + cnt) > nr_irqs)
786 return;
787
788 mutex_lock(&sparse_irq_lock);
789 for (i = 0; i < cnt; i++)
790 free_desc(from + i);
791
792 mutex_unlock(&sparse_irq_lock);
793}
794EXPORT_SYMBOL_GPL(irq_free_descs);
795
796/**
797 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
798 * @irq: Allocate for specific irq number if irq >= 0
799 * @from: Start the search from this irq number
800 * @cnt: Number of consecutive irqs to allocate.
801 * @node: Preferred node on which the irq descriptor should be allocated
802 * @owner: Owning module (can be NULL)
803 * @affinity: Optional pointer to an affinity mask array of size @cnt which
804 * hints where the irq descriptors should be allocated and which
805 * default affinities to use
806 *
807 * Returns the first irq number or error code
808 */
809int __ref
810__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
811 struct module *owner, const struct irq_affinity_desc *affinity)
812{
813 int start, ret;
814
815 if (!cnt)
816 return -EINVAL;
817
818 if (irq >= 0) {
819 if (from > irq)
820 return -EINVAL;
821 from = irq;
822 } else {
823 /*
824 * For interrupts which are freely allocated the
825 * architecture can force a lower bound to the @from
826 * argument. x86 uses this to exclude the GSI space.
827 */
828 from = arch_dynirq_lower_bound(from);
829 }
830
831 mutex_lock(&sparse_irq_lock);
832
833 start = irq_find_free_area(from, cnt);
834 ret = -EEXIST;
835 if (irq >=0 && start != irq)
836 goto unlock;
837
838 if (start + cnt > nr_irqs) {
839 ret = irq_expand_nr_irqs(start + cnt);
840 if (ret)
841 goto unlock;
842 }
843 ret = alloc_descs(start, cnt, node, affinity, owner);
844unlock:
845 mutex_unlock(&sparse_irq_lock);
846 return ret;
847}
848EXPORT_SYMBOL_GPL(__irq_alloc_descs);
849
850/**
851 * irq_get_next_irq - get next allocated irq number
852 * @offset: where to start the search
853 *
854 * Returns next irq number after offset or nr_irqs if none is found.
855 */
856unsigned int irq_get_next_irq(unsigned int offset)
857{
858 return irq_find_at_or_after(offset);
859}
860
861struct irq_desc *
862__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
863 unsigned int check)
864{
865 struct irq_desc *desc = irq_to_desc(irq);
866
867 if (desc) {
868 if (check & _IRQ_DESC_CHECK) {
869 if ((check & _IRQ_DESC_PERCPU) &&
870 !irq_settings_is_per_cpu_devid(desc))
871 return NULL;
872
873 if (!(check & _IRQ_DESC_PERCPU) &&
874 irq_settings_is_per_cpu_devid(desc))
875 return NULL;
876 }
877
878 if (bus)
879 chip_bus_lock(desc);
880 raw_spin_lock_irqsave(&desc->lock, *flags);
881 }
882 return desc;
883}
884
885void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
886 __releases(&desc->lock)
887{
888 raw_spin_unlock_irqrestore(&desc->lock, flags);
889 if (bus)
890 chip_bus_sync_unlock(desc);
891}
892
893int irq_set_percpu_devid_partition(unsigned int irq,
894 const struct cpumask *affinity)
895{
896 struct irq_desc *desc = irq_to_desc(irq);
897
898 if (!desc)
899 return -EINVAL;
900
901 if (desc->percpu_enabled)
902 return -EINVAL;
903
904 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
905
906 if (!desc->percpu_enabled)
907 return -ENOMEM;
908
909 if (affinity)
910 desc->percpu_affinity = affinity;
911 else
912 desc->percpu_affinity = cpu_possible_mask;
913
914 irq_set_percpu_devid_flags(irq);
915 return 0;
916}
917
918int irq_set_percpu_devid(unsigned int irq)
919{
920 return irq_set_percpu_devid_partition(irq, NULL);
921}
922
923int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
924{
925 struct irq_desc *desc = irq_to_desc(irq);
926
927 if (!desc || !desc->percpu_enabled)
928 return -EINVAL;
929
930 if (affinity)
931 cpumask_copy(affinity, desc->percpu_affinity);
932
933 return 0;
934}
935EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
936
937void kstat_incr_irq_this_cpu(unsigned int irq)
938{
939 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
940}
941
942/**
943 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
944 * @irq: The interrupt number
945 * @cpu: The cpu number
946 *
947 * Returns the sum of interrupt counts on @cpu since boot for
948 * @irq. The caller must ensure that the interrupt is not removed
949 * concurrently.
950 */
951unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
952{
953 struct irq_desc *desc = irq_to_desc(irq);
954
955 return desc && desc->kstat_irqs ?
956 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
957}
958
959static bool irq_is_nmi(struct irq_desc *desc)
960{
961 return desc->istate & IRQS_NMI;
962}
963
964static unsigned int kstat_irqs(unsigned int irq)
965{
966 struct irq_desc *desc = irq_to_desc(irq);
967 unsigned int sum = 0;
968 int cpu;
969
970 if (!desc || !desc->kstat_irqs)
971 return 0;
972 if (!irq_settings_is_per_cpu_devid(desc) &&
973 !irq_settings_is_per_cpu(desc) &&
974 !irq_is_nmi(desc))
975 return data_race(desc->tot_count);
976
977 for_each_possible_cpu(cpu)
978 sum += data_race(*per_cpu_ptr(desc->kstat_irqs, cpu));
979 return sum;
980}
981
982/**
983 * kstat_irqs_usr - Get the statistics for an interrupt from thread context
984 * @irq: The interrupt number
985 *
986 * Returns the sum of interrupt counts on all cpus since boot for @irq.
987 *
988 * It uses rcu to protect the access since a concurrent removal of an
989 * interrupt descriptor is observing an rcu grace period before
990 * delayed_free_desc()/irq_kobj_release().
991 */
992unsigned int kstat_irqs_usr(unsigned int irq)
993{
994 unsigned int sum;
995
996 rcu_read_lock();
997 sum = kstat_irqs(irq);
998 rcu_read_unlock();
999 return sum;
1000}
1001
1002#ifdef CONFIG_LOCKDEP
1003void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
1004 struct lock_class_key *request_class)
1005{
1006 struct irq_desc *desc = irq_to_desc(irq);
1007
1008 if (desc) {
1009 lockdep_set_class(&desc->lock, lock_class);
1010 lockdep_set_class(&desc->request_mutex, request_class);
1011 }
1012}
1013EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1014#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/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, "%d\n", (int)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 (action = desc->action; action != NULL; action = action->next) {
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.
292 */
293 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
294 pr_warn("Failed to add kobject for irq %d\n", irq);
295 }
296}
297
298static void irq_sysfs_del(struct irq_desc *desc)
299{
300 /*
301 * If irq_sysfs_init() has not yet been invoked (early boot), then
302 * irq_kobj_base is NULL and the descriptor was never added.
303 * kobject_del() complains about a object with no parent, so make
304 * it conditional.
305 */
306 if (irq_kobj_base)
307 kobject_del(&desc->kobj);
308}
309
310static int __init irq_sysfs_init(void)
311{
312 struct irq_desc *desc;
313 int irq;
314
315 /* Prevent concurrent irq alloc/free */
316 irq_lock_sparse();
317
318 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
319 if (!irq_kobj_base) {
320 irq_unlock_sparse();
321 return -ENOMEM;
322 }
323
324 /* Add the already allocated interrupts */
325 for_each_irq_desc(irq, desc)
326 irq_sysfs_add(irq, desc);
327 irq_unlock_sparse();
328
329 return 0;
330}
331postcore_initcall(irq_sysfs_init);
332
333#else /* !CONFIG_SYSFS */
334
335static struct kobj_type irq_kobj_type = {
336 .release = irq_kobj_release,
337};
338
339static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
340static void irq_sysfs_del(struct irq_desc *desc) {}
341
342#endif /* CONFIG_SYSFS */
343
344static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
345
346static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
347{
348 radix_tree_insert(&irq_desc_tree, irq, desc);
349}
350
351struct irq_desc *irq_to_desc(unsigned int irq)
352{
353 return radix_tree_lookup(&irq_desc_tree, irq);
354}
355#ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
356EXPORT_SYMBOL_GPL(irq_to_desc);
357#endif
358
359static void delete_irq_desc(unsigned int irq)
360{
361 radix_tree_delete(&irq_desc_tree, irq);
362}
363
364#ifdef CONFIG_SMP
365static void free_masks(struct irq_desc *desc)
366{
367#ifdef CONFIG_GENERIC_PENDING_IRQ
368 free_cpumask_var(desc->pending_mask);
369#endif
370 free_cpumask_var(desc->irq_common_data.affinity);
371#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
372 free_cpumask_var(desc->irq_common_data.effective_affinity);
373#endif
374}
375#else
376static inline void free_masks(struct irq_desc *desc) { }
377#endif
378
379void irq_lock_sparse(void)
380{
381 mutex_lock(&sparse_irq_lock);
382}
383
384void irq_unlock_sparse(void)
385{
386 mutex_unlock(&sparse_irq_lock);
387}
388
389static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
390 const struct cpumask *affinity,
391 struct module *owner)
392{
393 struct irq_desc *desc;
394
395 desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
396 if (!desc)
397 return NULL;
398 /* allocate based on nr_cpu_ids */
399 desc->kstat_irqs = alloc_percpu(unsigned int);
400 if (!desc->kstat_irqs)
401 goto err_desc;
402
403 if (alloc_masks(desc, node))
404 goto err_kstat;
405
406 raw_spin_lock_init(&desc->lock);
407 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
408 mutex_init(&desc->request_mutex);
409 init_rcu_head(&desc->rcu);
410
411 desc_set_defaults(irq, desc, node, affinity, owner);
412 irqd_set(&desc->irq_data, flags);
413 kobject_init(&desc->kobj, &irq_kobj_type);
414
415 return desc;
416
417err_kstat:
418 free_percpu(desc->kstat_irqs);
419err_desc:
420 kfree(desc);
421 return NULL;
422}
423
424static void irq_kobj_release(struct kobject *kobj)
425{
426 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
427
428 free_masks(desc);
429 free_percpu(desc->kstat_irqs);
430 kfree(desc);
431}
432
433static void delayed_free_desc(struct rcu_head *rhp)
434{
435 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
436
437 kobject_put(&desc->kobj);
438}
439
440static void free_desc(unsigned int irq)
441{
442 struct irq_desc *desc = irq_to_desc(irq);
443
444 irq_remove_debugfs_entry(desc);
445 unregister_irq_proc(irq, desc);
446
447 /*
448 * sparse_irq_lock protects also show_interrupts() and
449 * kstat_irq_usr(). Once we deleted the descriptor from the
450 * sparse tree we can free it. Access in proc will fail to
451 * lookup the descriptor.
452 *
453 * The sysfs entry must be serialized against a concurrent
454 * irq_sysfs_init() as well.
455 */
456 irq_sysfs_del(desc);
457 delete_irq_desc(irq);
458
459 /*
460 * We free the descriptor, masks and stat fields via RCU. That
461 * allows demultiplex interrupts to do rcu based management of
462 * the child interrupts.
463 * This also allows us to use rcu in kstat_irqs_usr().
464 */
465 call_rcu(&desc->rcu, delayed_free_desc);
466}
467
468static int alloc_descs(unsigned int start, unsigned int cnt, int node,
469 const struct irq_affinity_desc *affinity,
470 struct module *owner)
471{
472 struct irq_desc *desc;
473 int i;
474
475 /* Validate affinity mask(s) */
476 if (affinity) {
477 for (i = 0; i < cnt; i++) {
478 if (cpumask_empty(&affinity[i].mask))
479 return -EINVAL;
480 }
481 }
482
483 for (i = 0; i < cnt; i++) {
484 const struct cpumask *mask = NULL;
485 unsigned int flags = 0;
486
487 if (affinity) {
488 if (affinity->is_managed) {
489 flags = IRQD_AFFINITY_MANAGED |
490 IRQD_MANAGED_SHUTDOWN;
491 }
492 mask = &affinity->mask;
493 node = cpu_to_node(cpumask_first(mask));
494 affinity++;
495 }
496
497 desc = alloc_desc(start + i, node, flags, mask, owner);
498 if (!desc)
499 goto err;
500 irq_insert_desc(start + i, desc);
501 irq_sysfs_add(start + i, desc);
502 irq_add_debugfs_entry(start + i, desc);
503 }
504 bitmap_set(allocated_irqs, start, cnt);
505 return start;
506
507err:
508 for (i--; i >= 0; i--)
509 free_desc(start + i);
510 return -ENOMEM;
511}
512
513static int irq_expand_nr_irqs(unsigned int nr)
514{
515 if (nr > IRQ_BITMAP_BITS)
516 return -ENOMEM;
517 nr_irqs = nr;
518 return 0;
519}
520
521int __init early_irq_init(void)
522{
523 int i, initcnt, node = first_online_node;
524 struct irq_desc *desc;
525
526 init_irq_default_affinity();
527
528 /* Let arch update nr_irqs and return the nr of preallocated irqs */
529 initcnt = arch_probe_nr_irqs();
530 printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
531 NR_IRQS, nr_irqs, initcnt);
532
533 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
534 nr_irqs = IRQ_BITMAP_BITS;
535
536 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
537 initcnt = IRQ_BITMAP_BITS;
538
539 if (initcnt > nr_irqs)
540 nr_irqs = initcnt;
541
542 for (i = 0; i < initcnt; i++) {
543 desc = alloc_desc(i, node, 0, NULL, NULL);
544 set_bit(i, allocated_irqs);
545 irq_insert_desc(i, desc);
546 }
547 return arch_early_irq_init();
548}
549
550#else /* !CONFIG_SPARSE_IRQ */
551
552struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
553 [0 ... NR_IRQS-1] = {
554 .handle_irq = handle_bad_irq,
555 .depth = 1,
556 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
557 }
558};
559
560int __init early_irq_init(void)
561{
562 int count, i, node = first_online_node;
563 struct irq_desc *desc;
564
565 init_irq_default_affinity();
566
567 printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
568
569 desc = irq_desc;
570 count = ARRAY_SIZE(irq_desc);
571
572 for (i = 0; i < count; i++) {
573 desc[i].kstat_irqs = alloc_percpu(unsigned int);
574 alloc_masks(&desc[i], node);
575 raw_spin_lock_init(&desc[i].lock);
576 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
577 mutex_init(&desc[i].request_mutex);
578 desc_set_defaults(i, &desc[i], node, NULL, NULL);
579 }
580 return arch_early_irq_init();
581}
582
583struct irq_desc *irq_to_desc(unsigned int irq)
584{
585 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
586}
587EXPORT_SYMBOL(irq_to_desc);
588
589static void free_desc(unsigned int irq)
590{
591 struct irq_desc *desc = irq_to_desc(irq);
592 unsigned long flags;
593
594 raw_spin_lock_irqsave(&desc->lock, flags);
595 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
596 raw_spin_unlock_irqrestore(&desc->lock, flags);
597}
598
599static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
600 const struct irq_affinity_desc *affinity,
601 struct module *owner)
602{
603 u32 i;
604
605 for (i = 0; i < cnt; i++) {
606 struct irq_desc *desc = irq_to_desc(start + i);
607
608 desc->owner = owner;
609 }
610 bitmap_set(allocated_irqs, start, cnt);
611 return start;
612}
613
614static int irq_expand_nr_irqs(unsigned int nr)
615{
616 return -ENOMEM;
617}
618
619void irq_mark_irq(unsigned int irq)
620{
621 mutex_lock(&sparse_irq_lock);
622 bitmap_set(allocated_irqs, irq, 1);
623 mutex_unlock(&sparse_irq_lock);
624}
625
626#ifdef CONFIG_GENERIC_IRQ_LEGACY
627void irq_init_desc(unsigned int irq)
628{
629 free_desc(irq);
630}
631#endif
632
633#endif /* !CONFIG_SPARSE_IRQ */
634
635int handle_irq_desc(struct irq_desc *desc)
636{
637 struct irq_data *data;
638
639 if (!desc)
640 return -EINVAL;
641
642 data = irq_desc_get_irq_data(desc);
643 if (WARN_ON_ONCE(!in_irq() && handle_enforce_irqctx(data)))
644 return -EPERM;
645
646 generic_handle_irq_desc(desc);
647 return 0;
648}
649EXPORT_SYMBOL_GPL(handle_irq_desc);
650
651/**
652 * generic_handle_irq - Invoke the handler for a particular irq
653 * @irq: The irq number to handle
654 *
655 */
656int generic_handle_irq(unsigned int irq)
657{
658 return handle_irq_desc(irq_to_desc(irq));
659}
660EXPORT_SYMBOL_GPL(generic_handle_irq);
661
662#ifdef CONFIG_IRQ_DOMAIN
663/**
664 * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
665 * to a domain, usually for a non-root interrupt
666 * controller
667 * @domain: The domain where to perform the lookup
668 * @hwirq: The HW irq number to convert to a logical one
669 *
670 * Returns: 0 on success, or -EINVAL if conversion has failed
671 *
672 */
673int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
674{
675 return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
676}
677EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
678
679#ifdef CONFIG_HANDLE_DOMAIN_IRQ
680/**
681 * handle_domain_irq - Invoke the handler for a HW irq belonging to a domain,
682 * usually for a root interrupt controller
683 * @domain: The domain where to perform the lookup
684 * @hwirq: The HW irq number to convert to a logical one
685 * @regs: Register file coming from the low-level handling code
686 *
687 * Returns: 0 on success, or -EINVAL if conversion has failed
688 */
689int handle_domain_irq(struct irq_domain *domain,
690 unsigned int hwirq, struct pt_regs *regs)
691{
692 struct pt_regs *old_regs = set_irq_regs(regs);
693 struct irq_desc *desc;
694 int ret = 0;
695
696 irq_enter();
697
698 /* The irqdomain code provides boundary checks */
699 desc = irq_resolve_mapping(domain, hwirq);
700 if (likely(desc))
701 handle_irq_desc(desc);
702 else
703 ret = -EINVAL;
704
705 irq_exit();
706 set_irq_regs(old_regs);
707 return ret;
708}
709
710/**
711 * handle_domain_nmi - Invoke the handler for a HW irq belonging to a domain
712 * @domain: The domain where to perform the lookup
713 * @hwirq: The HW irq number to convert to a logical one
714 * @regs: Register file coming from the low-level handling code
715 *
716 * This function must be called from an NMI context.
717 *
718 * Returns: 0 on success, or -EINVAL if conversion has failed
719 */
720int handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq,
721 struct pt_regs *regs)
722{
723 struct pt_regs *old_regs = set_irq_regs(regs);
724 struct irq_desc *desc;
725 int ret = 0;
726
727 /*
728 * NMI context needs to be setup earlier in order to deal with tracing.
729 */
730 WARN_ON(!in_nmi());
731
732 desc = irq_resolve_mapping(domain, hwirq);
733
734 /*
735 * ack_bad_irq is not NMI-safe, just report
736 * an invalid interrupt.
737 */
738 if (likely(desc))
739 handle_irq_desc(desc);
740 else
741 ret = -EINVAL;
742
743 set_irq_regs(old_regs);
744 return ret;
745}
746#endif
747#endif
748
749/* Dynamic interrupt handling */
750
751/**
752 * irq_free_descs - free irq descriptors
753 * @from: Start of descriptor range
754 * @cnt: Number of consecutive irqs to free
755 */
756void irq_free_descs(unsigned int from, unsigned int cnt)
757{
758 int i;
759
760 if (from >= nr_irqs || (from + cnt) > nr_irqs)
761 return;
762
763 mutex_lock(&sparse_irq_lock);
764 for (i = 0; i < cnt; i++)
765 free_desc(from + i);
766
767 bitmap_clear(allocated_irqs, from, cnt);
768 mutex_unlock(&sparse_irq_lock);
769}
770EXPORT_SYMBOL_GPL(irq_free_descs);
771
772/**
773 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
774 * @irq: Allocate for specific irq number if irq >= 0
775 * @from: Start the search from this irq number
776 * @cnt: Number of consecutive irqs to allocate.
777 * @node: Preferred node on which the irq descriptor should be allocated
778 * @owner: Owning module (can be NULL)
779 * @affinity: Optional pointer to an affinity mask array of size @cnt which
780 * hints where the irq descriptors should be allocated and which
781 * default affinities to use
782 *
783 * Returns the first irq number or error code
784 */
785int __ref
786__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
787 struct module *owner, const struct irq_affinity_desc *affinity)
788{
789 int start, ret;
790
791 if (!cnt)
792 return -EINVAL;
793
794 if (irq >= 0) {
795 if (from > irq)
796 return -EINVAL;
797 from = irq;
798 } else {
799 /*
800 * For interrupts which are freely allocated the
801 * architecture can force a lower bound to the @from
802 * argument. x86 uses this to exclude the GSI space.
803 */
804 from = arch_dynirq_lower_bound(from);
805 }
806
807 mutex_lock(&sparse_irq_lock);
808
809 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
810 from, cnt, 0);
811 ret = -EEXIST;
812 if (irq >=0 && start != irq)
813 goto unlock;
814
815 if (start + cnt > nr_irqs) {
816 ret = irq_expand_nr_irqs(start + cnt);
817 if (ret)
818 goto unlock;
819 }
820 ret = alloc_descs(start, cnt, node, affinity, owner);
821unlock:
822 mutex_unlock(&sparse_irq_lock);
823 return ret;
824}
825EXPORT_SYMBOL_GPL(__irq_alloc_descs);
826
827/**
828 * irq_get_next_irq - get next allocated irq number
829 * @offset: where to start the search
830 *
831 * Returns next irq number after offset or nr_irqs if none is found.
832 */
833unsigned int irq_get_next_irq(unsigned int offset)
834{
835 return find_next_bit(allocated_irqs, nr_irqs, offset);
836}
837
838struct irq_desc *
839__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
840 unsigned int check)
841{
842 struct irq_desc *desc = irq_to_desc(irq);
843
844 if (desc) {
845 if (check & _IRQ_DESC_CHECK) {
846 if ((check & _IRQ_DESC_PERCPU) &&
847 !irq_settings_is_per_cpu_devid(desc))
848 return NULL;
849
850 if (!(check & _IRQ_DESC_PERCPU) &&
851 irq_settings_is_per_cpu_devid(desc))
852 return NULL;
853 }
854
855 if (bus)
856 chip_bus_lock(desc);
857 raw_spin_lock_irqsave(&desc->lock, *flags);
858 }
859 return desc;
860}
861
862void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
863 __releases(&desc->lock)
864{
865 raw_spin_unlock_irqrestore(&desc->lock, flags);
866 if (bus)
867 chip_bus_sync_unlock(desc);
868}
869
870int irq_set_percpu_devid_partition(unsigned int irq,
871 const struct cpumask *affinity)
872{
873 struct irq_desc *desc = irq_to_desc(irq);
874
875 if (!desc)
876 return -EINVAL;
877
878 if (desc->percpu_enabled)
879 return -EINVAL;
880
881 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
882
883 if (!desc->percpu_enabled)
884 return -ENOMEM;
885
886 if (affinity)
887 desc->percpu_affinity = affinity;
888 else
889 desc->percpu_affinity = cpu_possible_mask;
890
891 irq_set_percpu_devid_flags(irq);
892 return 0;
893}
894
895int irq_set_percpu_devid(unsigned int irq)
896{
897 return irq_set_percpu_devid_partition(irq, NULL);
898}
899
900int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
901{
902 struct irq_desc *desc = irq_to_desc(irq);
903
904 if (!desc || !desc->percpu_enabled)
905 return -EINVAL;
906
907 if (affinity)
908 cpumask_copy(affinity, desc->percpu_affinity);
909
910 return 0;
911}
912EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
913
914void kstat_incr_irq_this_cpu(unsigned int irq)
915{
916 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
917}
918
919/**
920 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
921 * @irq: The interrupt number
922 * @cpu: The cpu number
923 *
924 * Returns the sum of interrupt counts on @cpu since boot for
925 * @irq. The caller must ensure that the interrupt is not removed
926 * concurrently.
927 */
928unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
929{
930 struct irq_desc *desc = irq_to_desc(irq);
931
932 return desc && desc->kstat_irqs ?
933 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
934}
935
936static bool irq_is_nmi(struct irq_desc *desc)
937{
938 return desc->istate & IRQS_NMI;
939}
940
941static unsigned int kstat_irqs(unsigned int irq)
942{
943 struct irq_desc *desc = irq_to_desc(irq);
944 unsigned int sum = 0;
945 int cpu;
946
947 if (!desc || !desc->kstat_irqs)
948 return 0;
949 if (!irq_settings_is_per_cpu_devid(desc) &&
950 !irq_settings_is_per_cpu(desc) &&
951 !irq_is_nmi(desc))
952 return data_race(desc->tot_count);
953
954 for_each_possible_cpu(cpu)
955 sum += data_race(*per_cpu_ptr(desc->kstat_irqs, cpu));
956 return sum;
957}
958
959/**
960 * kstat_irqs_usr - Get the statistics for an interrupt from thread context
961 * @irq: The interrupt number
962 *
963 * Returns the sum of interrupt counts on all cpus since boot for @irq.
964 *
965 * It uses rcu to protect the access since a concurrent removal of an
966 * interrupt descriptor is observing an rcu grace period before
967 * delayed_free_desc()/irq_kobj_release().
968 */
969unsigned int kstat_irqs_usr(unsigned int irq)
970{
971 unsigned int sum;
972
973 rcu_read_lock();
974 sum = kstat_irqs(irq);
975 rcu_read_unlock();
976 return sum;
977}
978
979#ifdef CONFIG_LOCKDEP
980void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
981 struct lock_class_key *request_class)
982{
983 struct irq_desc *desc = irq_to_desc(irq);
984
985 if (desc) {
986 lockdep_set_class(&desc->lock, lock_class);
987 lockdep_set_class(&desc->request_mutex, request_class);
988 }
989}
990EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
991#endif