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1/*
2 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
3 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
4 *
5 * This file contains the interrupt descriptor management code
6 *
7 * Detailed information is available in Documentation/DocBook/genericirq
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 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
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 comandline 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#ifdef CONFIG_CPUMASK_OFFSTACK
44 if (!irq_default_affinity)
45 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
46#endif
47 if (cpumask_empty(irq_default_affinity))
48 cpumask_setall(irq_default_affinity);
49}
50#else
51static void __init init_irq_default_affinity(void)
52{
53}
54#endif
55
56#ifdef CONFIG_SMP
57static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
58{
59 if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
60 gfp, node))
61 return -ENOMEM;
62
63#ifdef CONFIG_GENERIC_PENDING_IRQ
64 if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
65 free_cpumask_var(desc->irq_common_data.affinity);
66 return -ENOMEM;
67 }
68#endif
69 return 0;
70}
71
72static void desc_smp_init(struct irq_desc *desc, int node,
73 const struct cpumask *affinity)
74{
75 if (!affinity)
76 affinity = irq_default_affinity;
77 cpumask_copy(desc->irq_common_data.affinity, affinity);
78
79#ifdef CONFIG_GENERIC_PENDING_IRQ
80 cpumask_clear(desc->pending_mask);
81#endif
82#ifdef CONFIG_NUMA
83 desc->irq_common_data.node = node;
84#endif
85}
86
87#else
88static inline int
89alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
90static inline void
91desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
92#endif
93
94static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
95 const struct cpumask *affinity, struct module *owner)
96{
97 int cpu;
98
99 desc->irq_common_data.handler_data = NULL;
100 desc->irq_common_data.msi_desc = NULL;
101
102 desc->irq_data.common = &desc->irq_common_data;
103 desc->irq_data.irq = irq;
104 desc->irq_data.chip = &no_irq_chip;
105 desc->irq_data.chip_data = NULL;
106 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
107 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
108 desc->handle_irq = handle_bad_irq;
109 desc->depth = 1;
110 desc->irq_count = 0;
111 desc->irqs_unhandled = 0;
112 desc->name = NULL;
113 desc->owner = owner;
114 for_each_possible_cpu(cpu)
115 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
116 desc_smp_init(desc, node, affinity);
117}
118
119int nr_irqs = NR_IRQS;
120EXPORT_SYMBOL_GPL(nr_irqs);
121
122static DEFINE_MUTEX(sparse_irq_lock);
123static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
124
125#ifdef CONFIG_SPARSE_IRQ
126
127static void irq_kobj_release(struct kobject *kobj);
128
129#ifdef CONFIG_SYSFS
130static struct kobject *irq_kobj_base;
131
132#define IRQ_ATTR_RO(_name) \
133static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
134
135static ssize_t per_cpu_count_show(struct kobject *kobj,
136 struct kobj_attribute *attr, char *buf)
137{
138 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
139 int cpu, irq = desc->irq_data.irq;
140 ssize_t ret = 0;
141 char *p = "";
142
143 for_each_possible_cpu(cpu) {
144 unsigned int c = kstat_irqs_cpu(irq, cpu);
145
146 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
147 p = ",";
148 }
149
150 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
151 return ret;
152}
153IRQ_ATTR_RO(per_cpu_count);
154
155static ssize_t chip_name_show(struct kobject *kobj,
156 struct kobj_attribute *attr, char *buf)
157{
158 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
159 ssize_t ret = 0;
160
161 raw_spin_lock_irq(&desc->lock);
162 if (desc->irq_data.chip && desc->irq_data.chip->name) {
163 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
164 desc->irq_data.chip->name);
165 }
166 raw_spin_unlock_irq(&desc->lock);
167
168 return ret;
169}
170IRQ_ATTR_RO(chip_name);
171
172static ssize_t hwirq_show(struct kobject *kobj,
173 struct kobj_attribute *attr, char *buf)
174{
175 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
176 ssize_t ret = 0;
177
178 raw_spin_lock_irq(&desc->lock);
179 if (desc->irq_data.domain)
180 ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq);
181 raw_spin_unlock_irq(&desc->lock);
182
183 return ret;
184}
185IRQ_ATTR_RO(hwirq);
186
187static ssize_t type_show(struct kobject *kobj,
188 struct kobj_attribute *attr, char *buf)
189{
190 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
191 ssize_t ret = 0;
192
193 raw_spin_lock_irq(&desc->lock);
194 ret = sprintf(buf, "%s\n",
195 irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
196 raw_spin_unlock_irq(&desc->lock);
197
198 return ret;
199
200}
201IRQ_ATTR_RO(type);
202
203static ssize_t name_show(struct kobject *kobj,
204 struct kobj_attribute *attr, char *buf)
205{
206 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
207 ssize_t ret = 0;
208
209 raw_spin_lock_irq(&desc->lock);
210 if (desc->name)
211 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
212 raw_spin_unlock_irq(&desc->lock);
213
214 return ret;
215}
216IRQ_ATTR_RO(name);
217
218static ssize_t actions_show(struct kobject *kobj,
219 struct kobj_attribute *attr, char *buf)
220{
221 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
222 struct irqaction *action;
223 ssize_t ret = 0;
224 char *p = "";
225
226 raw_spin_lock_irq(&desc->lock);
227 for (action = desc->action; action != NULL; action = action->next) {
228 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
229 p, action->name);
230 p = ",";
231 }
232 raw_spin_unlock_irq(&desc->lock);
233
234 if (ret)
235 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
236
237 return ret;
238}
239IRQ_ATTR_RO(actions);
240
241static struct attribute *irq_attrs[] = {
242 &per_cpu_count_attr.attr,
243 &chip_name_attr.attr,
244 &hwirq_attr.attr,
245 &type_attr.attr,
246 &name_attr.attr,
247 &actions_attr.attr,
248 NULL
249};
250
251static struct kobj_type irq_kobj_type = {
252 .release = irq_kobj_release,
253 .sysfs_ops = &kobj_sysfs_ops,
254 .default_attrs = irq_attrs,
255};
256
257static void irq_sysfs_add(int irq, struct irq_desc *desc)
258{
259 if (irq_kobj_base) {
260 /*
261 * Continue even in case of failure as this is nothing
262 * crucial.
263 */
264 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
265 pr_warn("Failed to add kobject for irq %d\n", irq);
266 }
267}
268
269static int __init irq_sysfs_init(void)
270{
271 struct irq_desc *desc;
272 int irq;
273
274 /* Prevent concurrent irq alloc/free */
275 irq_lock_sparse();
276
277 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
278 if (!irq_kobj_base) {
279 irq_unlock_sparse();
280 return -ENOMEM;
281 }
282
283 /* Add the already allocated interrupts */
284 for_each_irq_desc(irq, desc)
285 irq_sysfs_add(irq, desc);
286 irq_unlock_sparse();
287
288 return 0;
289}
290postcore_initcall(irq_sysfs_init);
291
292#else /* !CONFIG_SYSFS */
293
294static struct kobj_type irq_kobj_type = {
295 .release = irq_kobj_release,
296};
297
298static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
299
300#endif /* CONFIG_SYSFS */
301
302static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
303
304static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
305{
306 radix_tree_insert(&irq_desc_tree, irq, desc);
307}
308
309struct irq_desc *irq_to_desc(unsigned int irq)
310{
311 return radix_tree_lookup(&irq_desc_tree, irq);
312}
313EXPORT_SYMBOL(irq_to_desc);
314
315static void delete_irq_desc(unsigned int irq)
316{
317 radix_tree_delete(&irq_desc_tree, irq);
318}
319
320#ifdef CONFIG_SMP
321static void free_masks(struct irq_desc *desc)
322{
323#ifdef CONFIG_GENERIC_PENDING_IRQ
324 free_cpumask_var(desc->pending_mask);
325#endif
326 free_cpumask_var(desc->irq_common_data.affinity);
327}
328#else
329static inline void free_masks(struct irq_desc *desc) { }
330#endif
331
332void irq_lock_sparse(void)
333{
334 mutex_lock(&sparse_irq_lock);
335}
336
337void irq_unlock_sparse(void)
338{
339 mutex_unlock(&sparse_irq_lock);
340}
341
342static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
343 const struct cpumask *affinity,
344 struct module *owner)
345{
346 struct irq_desc *desc;
347 gfp_t gfp = GFP_KERNEL;
348
349 desc = kzalloc_node(sizeof(*desc), gfp, node);
350 if (!desc)
351 return NULL;
352 /* allocate based on nr_cpu_ids */
353 desc->kstat_irqs = alloc_percpu(unsigned int);
354 if (!desc->kstat_irqs)
355 goto err_desc;
356
357 if (alloc_masks(desc, gfp, node))
358 goto err_kstat;
359
360 raw_spin_lock_init(&desc->lock);
361 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
362 init_rcu_head(&desc->rcu);
363
364 desc_set_defaults(irq, desc, node, affinity, owner);
365 irqd_set(&desc->irq_data, flags);
366 kobject_init(&desc->kobj, &irq_kobj_type);
367
368 return desc;
369
370err_kstat:
371 free_percpu(desc->kstat_irqs);
372err_desc:
373 kfree(desc);
374 return NULL;
375}
376
377static void irq_kobj_release(struct kobject *kobj)
378{
379 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
380
381 free_masks(desc);
382 free_percpu(desc->kstat_irqs);
383 kfree(desc);
384}
385
386static void delayed_free_desc(struct rcu_head *rhp)
387{
388 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
389
390 kobject_put(&desc->kobj);
391}
392
393static void free_desc(unsigned int irq)
394{
395 struct irq_desc *desc = irq_to_desc(irq);
396
397 unregister_irq_proc(irq, desc);
398
399 /*
400 * sparse_irq_lock protects also show_interrupts() and
401 * kstat_irq_usr(). Once we deleted the descriptor from the
402 * sparse tree we can free it. Access in proc will fail to
403 * lookup the descriptor.
404 *
405 * The sysfs entry must be serialized against a concurrent
406 * irq_sysfs_init() as well.
407 */
408 mutex_lock(&sparse_irq_lock);
409 kobject_del(&desc->kobj);
410 delete_irq_desc(irq);
411 mutex_unlock(&sparse_irq_lock);
412
413 /*
414 * We free the descriptor, masks and stat fields via RCU. That
415 * allows demultiplex interrupts to do rcu based management of
416 * the child interrupts.
417 */
418 call_rcu(&desc->rcu, delayed_free_desc);
419}
420
421static int alloc_descs(unsigned int start, unsigned int cnt, int node,
422 const struct cpumask *affinity, struct module *owner)
423{
424 const struct cpumask *mask = NULL;
425 struct irq_desc *desc;
426 unsigned int flags;
427 int i;
428
429 /* Validate affinity mask(s) */
430 if (affinity) {
431 for (i = 0, mask = affinity; i < cnt; i++, mask++) {
432 if (cpumask_empty(mask))
433 return -EINVAL;
434 }
435 }
436
437 flags = affinity ? IRQD_AFFINITY_MANAGED : 0;
438 mask = NULL;
439
440 for (i = 0; i < cnt; i++) {
441 if (affinity) {
442 node = cpu_to_node(cpumask_first(affinity));
443 mask = affinity;
444 affinity++;
445 }
446 desc = alloc_desc(start + i, node, flags, mask, owner);
447 if (!desc)
448 goto err;
449 mutex_lock(&sparse_irq_lock);
450 irq_insert_desc(start + i, desc);
451 irq_sysfs_add(start + i, desc);
452 mutex_unlock(&sparse_irq_lock);
453 }
454 return start;
455
456err:
457 for (i--; i >= 0; i--)
458 free_desc(start + i);
459
460 mutex_lock(&sparse_irq_lock);
461 bitmap_clear(allocated_irqs, start, cnt);
462 mutex_unlock(&sparse_irq_lock);
463 return -ENOMEM;
464}
465
466static int irq_expand_nr_irqs(unsigned int nr)
467{
468 if (nr > IRQ_BITMAP_BITS)
469 return -ENOMEM;
470 nr_irqs = nr;
471 return 0;
472}
473
474int __init early_irq_init(void)
475{
476 int i, initcnt, node = first_online_node;
477 struct irq_desc *desc;
478
479 init_irq_default_affinity();
480
481 /* Let arch update nr_irqs and return the nr of preallocated irqs */
482 initcnt = arch_probe_nr_irqs();
483 printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
484
485 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
486 nr_irqs = IRQ_BITMAP_BITS;
487
488 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
489 initcnt = IRQ_BITMAP_BITS;
490
491 if (initcnt > nr_irqs)
492 nr_irqs = initcnt;
493
494 for (i = 0; i < initcnt; i++) {
495 desc = alloc_desc(i, node, 0, NULL, NULL);
496 set_bit(i, allocated_irqs);
497 irq_insert_desc(i, desc);
498 }
499 return arch_early_irq_init();
500}
501
502#else /* !CONFIG_SPARSE_IRQ */
503
504struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
505 [0 ... NR_IRQS-1] = {
506 .handle_irq = handle_bad_irq,
507 .depth = 1,
508 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
509 }
510};
511
512int __init early_irq_init(void)
513{
514 int count, i, node = first_online_node;
515 struct irq_desc *desc;
516
517 init_irq_default_affinity();
518
519 printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
520
521 desc = irq_desc;
522 count = ARRAY_SIZE(irq_desc);
523
524 for (i = 0; i < count; i++) {
525 desc[i].kstat_irqs = alloc_percpu(unsigned int);
526 alloc_masks(&desc[i], GFP_KERNEL, node);
527 raw_spin_lock_init(&desc[i].lock);
528 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
529 desc_set_defaults(i, &desc[i], node, NULL, NULL);
530 }
531 return arch_early_irq_init();
532}
533
534struct irq_desc *irq_to_desc(unsigned int irq)
535{
536 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
537}
538EXPORT_SYMBOL(irq_to_desc);
539
540static void free_desc(unsigned int irq)
541{
542 struct irq_desc *desc = irq_to_desc(irq);
543 unsigned long flags;
544
545 raw_spin_lock_irqsave(&desc->lock, flags);
546 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
547 raw_spin_unlock_irqrestore(&desc->lock, flags);
548}
549
550static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
551 const struct cpumask *affinity,
552 struct module *owner)
553{
554 u32 i;
555
556 for (i = 0; i < cnt; i++) {
557 struct irq_desc *desc = irq_to_desc(start + i);
558
559 desc->owner = owner;
560 }
561 return start;
562}
563
564static int irq_expand_nr_irqs(unsigned int nr)
565{
566 return -ENOMEM;
567}
568
569void irq_mark_irq(unsigned int irq)
570{
571 mutex_lock(&sparse_irq_lock);
572 bitmap_set(allocated_irqs, irq, 1);
573 mutex_unlock(&sparse_irq_lock);
574}
575
576#ifdef CONFIG_GENERIC_IRQ_LEGACY
577void irq_init_desc(unsigned int irq)
578{
579 free_desc(irq);
580}
581#endif
582
583#endif /* !CONFIG_SPARSE_IRQ */
584
585/**
586 * generic_handle_irq - Invoke the handler for a particular irq
587 * @irq: The irq number to handle
588 *
589 */
590int generic_handle_irq(unsigned int irq)
591{
592 struct irq_desc *desc = irq_to_desc(irq);
593
594 if (!desc)
595 return -EINVAL;
596 generic_handle_irq_desc(desc);
597 return 0;
598}
599EXPORT_SYMBOL_GPL(generic_handle_irq);
600
601#ifdef CONFIG_HANDLE_DOMAIN_IRQ
602/**
603 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
604 * @domain: The domain where to perform the lookup
605 * @hwirq: The HW irq number to convert to a logical one
606 * @lookup: Whether to perform the domain lookup or not
607 * @regs: Register file coming from the low-level handling code
608 *
609 * Returns: 0 on success, or -EINVAL if conversion has failed
610 */
611int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
612 bool lookup, struct pt_regs *regs)
613{
614 struct pt_regs *old_regs = set_irq_regs(regs);
615 unsigned int irq = hwirq;
616 int ret = 0;
617
618 irq_enter();
619
620#ifdef CONFIG_IRQ_DOMAIN
621 if (lookup)
622 irq = irq_find_mapping(domain, hwirq);
623#endif
624
625 /*
626 * Some hardware gives randomly wrong interrupts. Rather
627 * than crashing, do something sensible.
628 */
629 if (unlikely(!irq || irq >= nr_irqs)) {
630 ack_bad_irq(irq);
631 ret = -EINVAL;
632 } else {
633 generic_handle_irq(irq);
634 }
635
636 irq_exit();
637 set_irq_regs(old_regs);
638 return ret;
639}
640#endif
641
642/* Dynamic interrupt handling */
643
644/**
645 * irq_free_descs - free irq descriptors
646 * @from: Start of descriptor range
647 * @cnt: Number of consecutive irqs to free
648 */
649void irq_free_descs(unsigned int from, unsigned int cnt)
650{
651 int i;
652
653 if (from >= nr_irqs || (from + cnt) > nr_irqs)
654 return;
655
656 for (i = 0; i < cnt; i++)
657 free_desc(from + i);
658
659 mutex_lock(&sparse_irq_lock);
660 bitmap_clear(allocated_irqs, from, cnt);
661 mutex_unlock(&sparse_irq_lock);
662}
663EXPORT_SYMBOL_GPL(irq_free_descs);
664
665/**
666 * irq_alloc_descs - allocate and initialize a range of irq descriptors
667 * @irq: Allocate for specific irq number if irq >= 0
668 * @from: Start the search from this irq number
669 * @cnt: Number of consecutive irqs to allocate.
670 * @node: Preferred node on which the irq descriptor should be allocated
671 * @owner: Owning module (can be NULL)
672 * @affinity: Optional pointer to an affinity mask array of size @cnt which
673 * hints where the irq descriptors should be allocated and which
674 * default affinities to use
675 *
676 * Returns the first irq number or error code
677 */
678int __ref
679__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
680 struct module *owner, const struct cpumask *affinity)
681{
682 int start, ret;
683
684 if (!cnt)
685 return -EINVAL;
686
687 if (irq >= 0) {
688 if (from > irq)
689 return -EINVAL;
690 from = irq;
691 } else {
692 /*
693 * For interrupts which are freely allocated the
694 * architecture can force a lower bound to the @from
695 * argument. x86 uses this to exclude the GSI space.
696 */
697 from = arch_dynirq_lower_bound(from);
698 }
699
700 mutex_lock(&sparse_irq_lock);
701
702 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
703 from, cnt, 0);
704 ret = -EEXIST;
705 if (irq >=0 && start != irq)
706 goto err;
707
708 if (start + cnt > nr_irqs) {
709 ret = irq_expand_nr_irqs(start + cnt);
710 if (ret)
711 goto err;
712 }
713
714 bitmap_set(allocated_irqs, start, cnt);
715 mutex_unlock(&sparse_irq_lock);
716 return alloc_descs(start, cnt, node, affinity, owner);
717
718err:
719 mutex_unlock(&sparse_irq_lock);
720 return ret;
721}
722EXPORT_SYMBOL_GPL(__irq_alloc_descs);
723
724#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
725/**
726 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
727 * @cnt: number of interrupts to allocate
728 * @node: node on which to allocate
729 *
730 * Returns an interrupt number > 0 or 0, if the allocation fails.
731 */
732unsigned int irq_alloc_hwirqs(int cnt, int node)
733{
734 int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL);
735
736 if (irq < 0)
737 return 0;
738
739 for (i = irq; cnt > 0; i++, cnt--) {
740 if (arch_setup_hwirq(i, node))
741 goto err;
742 irq_clear_status_flags(i, _IRQ_NOREQUEST);
743 }
744 return irq;
745
746err:
747 for (i--; i >= irq; i--) {
748 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
749 arch_teardown_hwirq(i);
750 }
751 irq_free_descs(irq, cnt);
752 return 0;
753}
754EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
755
756/**
757 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
758 * @from: Free from irq number
759 * @cnt: number of interrupts to free
760 *
761 */
762void irq_free_hwirqs(unsigned int from, int cnt)
763{
764 int i, j;
765
766 for (i = from, j = cnt; j > 0; i++, j--) {
767 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
768 arch_teardown_hwirq(i);
769 }
770 irq_free_descs(from, cnt);
771}
772EXPORT_SYMBOL_GPL(irq_free_hwirqs);
773#endif
774
775/**
776 * irq_get_next_irq - get next allocated irq number
777 * @offset: where to start the search
778 *
779 * Returns next irq number after offset or nr_irqs if none is found.
780 */
781unsigned int irq_get_next_irq(unsigned int offset)
782{
783 return find_next_bit(allocated_irqs, nr_irqs, offset);
784}
785
786struct irq_desc *
787__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
788 unsigned int check)
789{
790 struct irq_desc *desc = irq_to_desc(irq);
791
792 if (desc) {
793 if (check & _IRQ_DESC_CHECK) {
794 if ((check & _IRQ_DESC_PERCPU) &&
795 !irq_settings_is_per_cpu_devid(desc))
796 return NULL;
797
798 if (!(check & _IRQ_DESC_PERCPU) &&
799 irq_settings_is_per_cpu_devid(desc))
800 return NULL;
801 }
802
803 if (bus)
804 chip_bus_lock(desc);
805 raw_spin_lock_irqsave(&desc->lock, *flags);
806 }
807 return desc;
808}
809
810void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
811{
812 raw_spin_unlock_irqrestore(&desc->lock, flags);
813 if (bus)
814 chip_bus_sync_unlock(desc);
815}
816
817int irq_set_percpu_devid_partition(unsigned int irq,
818 const struct cpumask *affinity)
819{
820 struct irq_desc *desc = irq_to_desc(irq);
821
822 if (!desc)
823 return -EINVAL;
824
825 if (desc->percpu_enabled)
826 return -EINVAL;
827
828 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
829
830 if (!desc->percpu_enabled)
831 return -ENOMEM;
832
833 if (affinity)
834 desc->percpu_affinity = affinity;
835 else
836 desc->percpu_affinity = cpu_possible_mask;
837
838 irq_set_percpu_devid_flags(irq);
839 return 0;
840}
841
842int irq_set_percpu_devid(unsigned int irq)
843{
844 return irq_set_percpu_devid_partition(irq, NULL);
845}
846
847int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
848{
849 struct irq_desc *desc = irq_to_desc(irq);
850
851 if (!desc || !desc->percpu_enabled)
852 return -EINVAL;
853
854 if (affinity)
855 cpumask_copy(affinity, desc->percpu_affinity);
856
857 return 0;
858}
859
860void kstat_incr_irq_this_cpu(unsigned int irq)
861{
862 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
863}
864
865/**
866 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
867 * @irq: The interrupt number
868 * @cpu: The cpu number
869 *
870 * Returns the sum of interrupt counts on @cpu since boot for
871 * @irq. The caller must ensure that the interrupt is not removed
872 * concurrently.
873 */
874unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
875{
876 struct irq_desc *desc = irq_to_desc(irq);
877
878 return desc && desc->kstat_irqs ?
879 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
880}
881
882/**
883 * kstat_irqs - Get the statistics for an interrupt
884 * @irq: The interrupt number
885 *
886 * Returns the sum of interrupt counts on all cpus since boot for
887 * @irq. The caller must ensure that the interrupt is not removed
888 * concurrently.
889 */
890unsigned int kstat_irqs(unsigned int irq)
891{
892 struct irq_desc *desc = irq_to_desc(irq);
893 int cpu;
894 unsigned int sum = 0;
895
896 if (!desc || !desc->kstat_irqs)
897 return 0;
898 for_each_possible_cpu(cpu)
899 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
900 return sum;
901}
902
903/**
904 * kstat_irqs_usr - Get the statistics for an interrupt
905 * @irq: The interrupt number
906 *
907 * Returns the sum of interrupt counts on all cpus since boot for
908 * @irq. Contrary to kstat_irqs() this can be called from any
909 * preemptible context. It's protected against concurrent removal of
910 * an interrupt descriptor when sparse irqs are enabled.
911 */
912unsigned int kstat_irqs_usr(unsigned int irq)
913{
914 unsigned int sum;
915
916 irq_lock_sparse();
917 sum = kstat_irqs(irq);
918 irq_unlock_sparse();
919 return sum;
920}
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