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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
4 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
5 *
6 * This file contains the interrupt descriptor management code. Detailed
7 * information is available in Documentation/core-api/genericirq.rst
8 *
9 */
10#include <linux/irq.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/interrupt.h>
14#include <linux/kernel_stat.h>
15#include <linux/radix-tree.h>
16#include <linux/bitmap.h>
17#include <linux/irqdomain.h>
18#include <linux/sysfs.h>
19
20#include "internals.h"
21
22/*
23 * lockdep: we want to handle all irq_desc locks as a single lock-class:
24 */
25static struct lock_class_key irq_desc_lock_class;
26
27#if defined(CONFIG_SMP)
28static int __init irq_affinity_setup(char *str)
29{
30 alloc_bootmem_cpumask_var(&irq_default_affinity);
31 cpulist_parse(str, irq_default_affinity);
32 /*
33 * Set at least the boot cpu. We don't want to end up with
34 * bugreports caused by random 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 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 int cpu, irq = desc->irq_data.irq;
151 ssize_t ret = 0;
152 char *p = "";
153
154 for_each_possible_cpu(cpu) {
155 unsigned int c = kstat_irqs_cpu(irq, 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}
355EXPORT_SYMBOL(irq_to_desc);
356
357static void delete_irq_desc(unsigned int irq)
358{
359 radix_tree_delete(&irq_desc_tree, irq);
360}
361
362#ifdef CONFIG_SMP
363static void free_masks(struct irq_desc *desc)
364{
365#ifdef CONFIG_GENERIC_PENDING_IRQ
366 free_cpumask_var(desc->pending_mask);
367#endif
368 free_cpumask_var(desc->irq_common_data.affinity);
369#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
370 free_cpumask_var(desc->irq_common_data.effective_affinity);
371#endif
372}
373#else
374static inline void free_masks(struct irq_desc *desc) { }
375#endif
376
377void irq_lock_sparse(void)
378{
379 mutex_lock(&sparse_irq_lock);
380}
381
382void irq_unlock_sparse(void)
383{
384 mutex_unlock(&sparse_irq_lock);
385}
386
387static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
388 const struct cpumask *affinity,
389 struct module *owner)
390{
391 struct irq_desc *desc;
392
393 desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
394 if (!desc)
395 return NULL;
396 /* allocate based on nr_cpu_ids */
397 desc->kstat_irqs = alloc_percpu(unsigned int);
398 if (!desc->kstat_irqs)
399 goto err_desc;
400
401 if (alloc_masks(desc, node))
402 goto err_kstat;
403
404 raw_spin_lock_init(&desc->lock);
405 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
406 mutex_init(&desc->request_mutex);
407 init_rcu_head(&desc->rcu);
408
409 desc_set_defaults(irq, desc, node, affinity, owner);
410 irqd_set(&desc->irq_data, flags);
411 kobject_init(&desc->kobj, &irq_kobj_type);
412
413 return desc;
414
415err_kstat:
416 free_percpu(desc->kstat_irqs);
417err_desc:
418 kfree(desc);
419 return NULL;
420}
421
422static void irq_kobj_release(struct kobject *kobj)
423{
424 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
425
426 free_masks(desc);
427 free_percpu(desc->kstat_irqs);
428 kfree(desc);
429}
430
431static void delayed_free_desc(struct rcu_head *rhp)
432{
433 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
434
435 kobject_put(&desc->kobj);
436}
437
438static void free_desc(unsigned int irq)
439{
440 struct irq_desc *desc = irq_to_desc(irq);
441
442 irq_remove_debugfs_entry(desc);
443 unregister_irq_proc(irq, desc);
444
445 /*
446 * sparse_irq_lock protects also show_interrupts() and
447 * kstat_irq_usr(). Once we deleted the descriptor from the
448 * sparse tree we can free it. Access in proc will fail to
449 * lookup the descriptor.
450 *
451 * The sysfs entry must be serialized against a concurrent
452 * irq_sysfs_init() as well.
453 */
454 irq_sysfs_del(desc);
455 delete_irq_desc(irq);
456
457 /*
458 * We free the descriptor, masks and stat fields via RCU. That
459 * allows demultiplex interrupts to do rcu based management of
460 * the child interrupts.
461 * This also allows us to use rcu in kstat_irqs_usr().
462 */
463 call_rcu(&desc->rcu, delayed_free_desc);
464}
465
466static int alloc_descs(unsigned int start, unsigned int cnt, int node,
467 const struct irq_affinity_desc *affinity,
468 struct module *owner)
469{
470 struct irq_desc *desc;
471 int i;
472
473 /* Validate affinity mask(s) */
474 if (affinity) {
475 for (i = 0; i < cnt; i++) {
476 if (cpumask_empty(&affinity[i].mask))
477 return -EINVAL;
478 }
479 }
480
481 for (i = 0; i < cnt; i++) {
482 const struct cpumask *mask = NULL;
483 unsigned int flags = 0;
484
485 if (affinity) {
486 if (affinity->is_managed) {
487 flags = IRQD_AFFINITY_MANAGED |
488 IRQD_MANAGED_SHUTDOWN;
489 }
490 mask = &affinity->mask;
491 node = cpu_to_node(cpumask_first(mask));
492 affinity++;
493 }
494
495 desc = alloc_desc(start + i, node, flags, mask, owner);
496 if (!desc)
497 goto err;
498 irq_insert_desc(start + i, desc);
499 irq_sysfs_add(start + i, desc);
500 irq_add_debugfs_entry(start + i, desc);
501 }
502 bitmap_set(allocated_irqs, start, cnt);
503 return start;
504
505err:
506 for (i--; i >= 0; i--)
507 free_desc(start + i);
508 return -ENOMEM;
509}
510
511static int irq_expand_nr_irqs(unsigned int nr)
512{
513 if (nr > IRQ_BITMAP_BITS)
514 return -ENOMEM;
515 nr_irqs = nr;
516 return 0;
517}
518
519int __init early_irq_init(void)
520{
521 int i, initcnt, node = first_online_node;
522 struct irq_desc *desc;
523
524 init_irq_default_affinity();
525
526 /* Let arch update nr_irqs and return the nr of preallocated irqs */
527 initcnt = arch_probe_nr_irqs();
528 printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
529 NR_IRQS, nr_irqs, initcnt);
530
531 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
532 nr_irqs = IRQ_BITMAP_BITS;
533
534 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
535 initcnt = IRQ_BITMAP_BITS;
536
537 if (initcnt > nr_irqs)
538 nr_irqs = initcnt;
539
540 for (i = 0; i < initcnt; i++) {
541 desc = alloc_desc(i, node, 0, NULL, NULL);
542 set_bit(i, allocated_irqs);
543 irq_insert_desc(i, desc);
544 }
545 return arch_early_irq_init();
546}
547
548#else /* !CONFIG_SPARSE_IRQ */
549
550struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
551 [0 ... NR_IRQS-1] = {
552 .handle_irq = handle_bad_irq,
553 .depth = 1,
554 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
555 }
556};
557
558int __init early_irq_init(void)
559{
560 int count, i, node = first_online_node;
561 struct irq_desc *desc;
562
563 init_irq_default_affinity();
564
565 printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
566
567 desc = irq_desc;
568 count = ARRAY_SIZE(irq_desc);
569
570 for (i = 0; i < count; i++) {
571 desc[i].kstat_irqs = alloc_percpu(unsigned int);
572 alloc_masks(&desc[i], node);
573 raw_spin_lock_init(&desc[i].lock);
574 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
575 mutex_init(&desc[i].request_mutex);
576 desc_set_defaults(i, &desc[i], node, NULL, NULL);
577 }
578 return arch_early_irq_init();
579}
580
581struct irq_desc *irq_to_desc(unsigned int irq)
582{
583 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
584}
585EXPORT_SYMBOL(irq_to_desc);
586
587static void free_desc(unsigned int irq)
588{
589 struct irq_desc *desc = irq_to_desc(irq);
590 unsigned long flags;
591
592 raw_spin_lock_irqsave(&desc->lock, flags);
593 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
594 raw_spin_unlock_irqrestore(&desc->lock, flags);
595}
596
597static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
598 const struct irq_affinity_desc *affinity,
599 struct module *owner)
600{
601 u32 i;
602
603 for (i = 0; i < cnt; i++) {
604 struct irq_desc *desc = irq_to_desc(start + i);
605
606 desc->owner = owner;
607 }
608 bitmap_set(allocated_irqs, start, cnt);
609 return start;
610}
611
612static int irq_expand_nr_irqs(unsigned int nr)
613{
614 return -ENOMEM;
615}
616
617void irq_mark_irq(unsigned int irq)
618{
619 mutex_lock(&sparse_irq_lock);
620 bitmap_set(allocated_irqs, irq, 1);
621 mutex_unlock(&sparse_irq_lock);
622}
623
624#ifdef CONFIG_GENERIC_IRQ_LEGACY
625void irq_init_desc(unsigned int irq)
626{
627 free_desc(irq);
628}
629#endif
630
631#endif /* !CONFIG_SPARSE_IRQ */
632
633/**
634 * generic_handle_irq - Invoke the handler for a particular irq
635 * @irq: The irq number to handle
636 *
637 */
638int generic_handle_irq(unsigned int irq)
639{
640 struct irq_desc *desc = irq_to_desc(irq);
641 struct irq_data *data;
642
643 if (!desc)
644 return -EINVAL;
645
646 data = irq_desc_get_irq_data(desc);
647 if (WARN_ON_ONCE(!in_irq() && handle_enforce_irqctx(data)))
648 return -EPERM;
649
650 generic_handle_irq_desc(desc);
651 return 0;
652}
653EXPORT_SYMBOL_GPL(generic_handle_irq);
654
655#ifdef CONFIG_HANDLE_DOMAIN_IRQ
656/**
657 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
658 * @domain: The domain where to perform the lookup
659 * @hwirq: The HW irq number to convert to a logical one
660 * @lookup: Whether to perform the domain lookup or not
661 * @regs: Register file coming from the low-level handling code
662 *
663 * Returns: 0 on success, or -EINVAL if conversion has failed
664 */
665int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
666 bool lookup, struct pt_regs *regs)
667{
668 struct pt_regs *old_regs = set_irq_regs(regs);
669 unsigned int irq = hwirq;
670 int ret = 0;
671
672 irq_enter();
673
674#ifdef CONFIG_IRQ_DOMAIN
675 if (lookup)
676 irq = irq_find_mapping(domain, hwirq);
677#endif
678
679 /*
680 * Some hardware gives randomly wrong interrupts. Rather
681 * than crashing, do something sensible.
682 */
683 if (unlikely(!irq || irq >= nr_irqs)) {
684 ack_bad_irq(irq);
685 ret = -EINVAL;
686 } else {
687 generic_handle_irq(irq);
688 }
689
690 irq_exit();
691 set_irq_regs(old_regs);
692 return ret;
693}
694
695#ifdef CONFIG_IRQ_DOMAIN
696/**
697 * handle_domain_nmi - Invoke the handler for a HW irq belonging to a domain
698 * @domain: The domain where to perform the lookup
699 * @hwirq: The HW irq number to convert to a logical one
700 * @regs: Register file coming from the low-level handling code
701 *
702 * This function must be called from an NMI context.
703 *
704 * Returns: 0 on success, or -EINVAL if conversion has failed
705 */
706int handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq,
707 struct pt_regs *regs)
708{
709 struct pt_regs *old_regs = set_irq_regs(regs);
710 unsigned int irq;
711 int ret = 0;
712
713 /*
714 * NMI context needs to be setup earlier in order to deal with tracing.
715 */
716 WARN_ON(!in_nmi());
717
718 irq = irq_find_mapping(domain, hwirq);
719
720 /*
721 * ack_bad_irq is not NMI-safe, just report
722 * an invalid interrupt.
723 */
724 if (likely(irq))
725 generic_handle_irq(irq);
726 else
727 ret = -EINVAL;
728
729 set_irq_regs(old_regs);
730 return ret;
731}
732#endif
733#endif
734
735/* Dynamic interrupt handling */
736
737/**
738 * irq_free_descs - free irq descriptors
739 * @from: Start of descriptor range
740 * @cnt: Number of consecutive irqs to free
741 */
742void irq_free_descs(unsigned int from, unsigned int cnt)
743{
744 int i;
745
746 if (from >= nr_irqs || (from + cnt) > nr_irqs)
747 return;
748
749 mutex_lock(&sparse_irq_lock);
750 for (i = 0; i < cnt; i++)
751 free_desc(from + i);
752
753 bitmap_clear(allocated_irqs, from, cnt);
754 mutex_unlock(&sparse_irq_lock);
755}
756EXPORT_SYMBOL_GPL(irq_free_descs);
757
758/**
759 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
760 * @irq: Allocate for specific irq number if irq >= 0
761 * @from: Start the search from this irq number
762 * @cnt: Number of consecutive irqs to allocate.
763 * @node: Preferred node on which the irq descriptor should be allocated
764 * @owner: Owning module (can be NULL)
765 * @affinity: Optional pointer to an affinity mask array of size @cnt which
766 * hints where the irq descriptors should be allocated and which
767 * default affinities to use
768 *
769 * Returns the first irq number or error code
770 */
771int __ref
772__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
773 struct module *owner, const struct irq_affinity_desc *affinity)
774{
775 int start, ret;
776
777 if (!cnt)
778 return -EINVAL;
779
780 if (irq >= 0) {
781 if (from > irq)
782 return -EINVAL;
783 from = irq;
784 } else {
785 /*
786 * For interrupts which are freely allocated the
787 * architecture can force a lower bound to the @from
788 * argument. x86 uses this to exclude the GSI space.
789 */
790 from = arch_dynirq_lower_bound(from);
791 }
792
793 mutex_lock(&sparse_irq_lock);
794
795 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
796 from, cnt, 0);
797 ret = -EEXIST;
798 if (irq >=0 && start != irq)
799 goto unlock;
800
801 if (start + cnt > nr_irqs) {
802 ret = irq_expand_nr_irqs(start + cnt);
803 if (ret)
804 goto unlock;
805 }
806 ret = alloc_descs(start, cnt, node, affinity, owner);
807unlock:
808 mutex_unlock(&sparse_irq_lock);
809 return ret;
810}
811EXPORT_SYMBOL_GPL(__irq_alloc_descs);
812
813#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
814/**
815 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
816 * @cnt: number of interrupts to allocate
817 * @node: node on which to allocate
818 *
819 * Returns an interrupt number > 0 or 0, if the allocation fails.
820 */
821unsigned int irq_alloc_hwirqs(int cnt, int node)
822{
823 int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL);
824
825 if (irq < 0)
826 return 0;
827
828 for (i = irq; cnt > 0; i++, cnt--) {
829 if (arch_setup_hwirq(i, node))
830 goto err;
831 irq_clear_status_flags(i, _IRQ_NOREQUEST);
832 }
833 return irq;
834
835err:
836 for (i--; i >= irq; i--) {
837 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
838 arch_teardown_hwirq(i);
839 }
840 irq_free_descs(irq, cnt);
841 return 0;
842}
843EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
844
845/**
846 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
847 * @from: Free from irq number
848 * @cnt: number of interrupts to free
849 *
850 */
851void irq_free_hwirqs(unsigned int from, int cnt)
852{
853 int i, j;
854
855 for (i = from, j = cnt; j > 0; i++, j--) {
856 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
857 arch_teardown_hwirq(i);
858 }
859 irq_free_descs(from, cnt);
860}
861EXPORT_SYMBOL_GPL(irq_free_hwirqs);
862#endif
863
864/**
865 * irq_get_next_irq - get next allocated irq number
866 * @offset: where to start the search
867 *
868 * Returns next irq number after offset or nr_irqs if none is found.
869 */
870unsigned int irq_get_next_irq(unsigned int offset)
871{
872 return find_next_bit(allocated_irqs, nr_irqs, offset);
873}
874
875struct irq_desc *
876__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
877 unsigned int check)
878{
879 struct irq_desc *desc = irq_to_desc(irq);
880
881 if (desc) {
882 if (check & _IRQ_DESC_CHECK) {
883 if ((check & _IRQ_DESC_PERCPU) &&
884 !irq_settings_is_per_cpu_devid(desc))
885 return NULL;
886
887 if (!(check & _IRQ_DESC_PERCPU) &&
888 irq_settings_is_per_cpu_devid(desc))
889 return NULL;
890 }
891
892 if (bus)
893 chip_bus_lock(desc);
894 raw_spin_lock_irqsave(&desc->lock, *flags);
895 }
896 return desc;
897}
898
899void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
900 __releases(&desc->lock)
901{
902 raw_spin_unlock_irqrestore(&desc->lock, flags);
903 if (bus)
904 chip_bus_sync_unlock(desc);
905}
906
907int irq_set_percpu_devid_partition(unsigned int irq,
908 const struct cpumask *affinity)
909{
910 struct irq_desc *desc = irq_to_desc(irq);
911
912 if (!desc)
913 return -EINVAL;
914
915 if (desc->percpu_enabled)
916 return -EINVAL;
917
918 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
919
920 if (!desc->percpu_enabled)
921 return -ENOMEM;
922
923 if (affinity)
924 desc->percpu_affinity = affinity;
925 else
926 desc->percpu_affinity = cpu_possible_mask;
927
928 irq_set_percpu_devid_flags(irq);
929 return 0;
930}
931
932int irq_set_percpu_devid(unsigned int irq)
933{
934 return irq_set_percpu_devid_partition(irq, NULL);
935}
936
937int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
938{
939 struct irq_desc *desc = irq_to_desc(irq);
940
941 if (!desc || !desc->percpu_enabled)
942 return -EINVAL;
943
944 if (affinity)
945 cpumask_copy(affinity, desc->percpu_affinity);
946
947 return 0;
948}
949EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
950
951void kstat_incr_irq_this_cpu(unsigned int irq)
952{
953 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
954}
955
956/**
957 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
958 * @irq: The interrupt number
959 * @cpu: The cpu number
960 *
961 * Returns the sum of interrupt counts on @cpu since boot for
962 * @irq. The caller must ensure that the interrupt is not removed
963 * concurrently.
964 */
965unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
966{
967 struct irq_desc *desc = irq_to_desc(irq);
968
969 return desc && desc->kstat_irqs ?
970 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
971}
972
973static bool irq_is_nmi(struct irq_desc *desc)
974{
975 return desc->istate & IRQS_NMI;
976}
977
978/**
979 * kstat_irqs - Get the statistics for an interrupt
980 * @irq: The interrupt number
981 *
982 * Returns the sum of interrupt counts on all cpus since boot for
983 * @irq. The caller must ensure that the interrupt is not removed
984 * concurrently.
985 */
986unsigned int kstat_irqs(unsigned int irq)
987{
988 struct irq_desc *desc = irq_to_desc(irq);
989 unsigned int sum = 0;
990 int cpu;
991
992 if (!desc || !desc->kstat_irqs)
993 return 0;
994 if (!irq_settings_is_per_cpu_devid(desc) &&
995 !irq_settings_is_per_cpu(desc) &&
996 !irq_is_nmi(desc))
997 return desc->tot_count;
998
999 for_each_possible_cpu(cpu)
1000 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
1001 return sum;
1002}
1003
1004/**
1005 * kstat_irqs_usr - Get the statistics for an interrupt
1006 * @irq: The interrupt number
1007 *
1008 * Returns the sum of interrupt counts on all cpus since boot for @irq.
1009 * Contrary to kstat_irqs() this can be called from any context.
1010 * It uses rcu since a concurrent removal of an interrupt descriptor is
1011 * observing an rcu grace period before delayed_free_desc()/irq_kobj_release().
1012 */
1013unsigned int kstat_irqs_usr(unsigned int irq)
1014{
1015 unsigned int sum;
1016
1017 rcu_read_lock();
1018 sum = kstat_irqs(irq);
1019 rcu_read_unlock();
1020 return sum;
1021}
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 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 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->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 DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
134
135#ifdef CONFIG_SPARSE_IRQ
136
137static void irq_kobj_release(struct kobject *kobj);
138
139#ifdef CONFIG_SYSFS
140static struct kobject *irq_kobj_base;
141
142#define IRQ_ATTR_RO(_name) \
143static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
144
145static ssize_t per_cpu_count_show(struct kobject *kobj,
146 struct kobj_attribute *attr, char *buf)
147{
148 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
149 int cpu, irq = desc->irq_data.irq;
150 ssize_t ret = 0;
151 char *p = "";
152
153 for_each_possible_cpu(cpu) {
154 unsigned int c = kstat_irqs_cpu(irq, cpu);
155
156 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
157 p = ",";
158 }
159
160 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
161 return ret;
162}
163IRQ_ATTR_RO(per_cpu_count);
164
165static ssize_t chip_name_show(struct kobject *kobj,
166 struct kobj_attribute *attr, char *buf)
167{
168 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
169 ssize_t ret = 0;
170
171 raw_spin_lock_irq(&desc->lock);
172 if (desc->irq_data.chip && desc->irq_data.chip->name) {
173 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
174 desc->irq_data.chip->name);
175 }
176 raw_spin_unlock_irq(&desc->lock);
177
178 return ret;
179}
180IRQ_ATTR_RO(chip_name);
181
182static ssize_t hwirq_show(struct kobject *kobj,
183 struct kobj_attribute *attr, char *buf)
184{
185 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
186 ssize_t ret = 0;
187
188 raw_spin_lock_irq(&desc->lock);
189 if (desc->irq_data.domain)
190 ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq);
191 raw_spin_unlock_irq(&desc->lock);
192
193 return ret;
194}
195IRQ_ATTR_RO(hwirq);
196
197static ssize_t type_show(struct kobject *kobj,
198 struct kobj_attribute *attr, char *buf)
199{
200 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
201 ssize_t ret = 0;
202
203 raw_spin_lock_irq(&desc->lock);
204 ret = sprintf(buf, "%s\n",
205 irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
206 raw_spin_unlock_irq(&desc->lock);
207
208 return ret;
209
210}
211IRQ_ATTR_RO(type);
212
213static ssize_t wakeup_show(struct kobject *kobj,
214 struct kobj_attribute *attr, char *buf)
215{
216 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
217 ssize_t ret = 0;
218
219 raw_spin_lock_irq(&desc->lock);
220 ret = sprintf(buf, "%s\n",
221 irqd_is_wakeup_set(&desc->irq_data) ? "enabled" : "disabled");
222 raw_spin_unlock_irq(&desc->lock);
223
224 return ret;
225
226}
227IRQ_ATTR_RO(wakeup);
228
229static ssize_t name_show(struct kobject *kobj,
230 struct kobj_attribute *attr, char *buf)
231{
232 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
233 ssize_t ret = 0;
234
235 raw_spin_lock_irq(&desc->lock);
236 if (desc->name)
237 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
238 raw_spin_unlock_irq(&desc->lock);
239
240 return ret;
241}
242IRQ_ATTR_RO(name);
243
244static ssize_t actions_show(struct kobject *kobj,
245 struct kobj_attribute *attr, char *buf)
246{
247 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
248 struct irqaction *action;
249 ssize_t ret = 0;
250 char *p = "";
251
252 raw_spin_lock_irq(&desc->lock);
253 for (action = desc->action; action != NULL; action = action->next) {
254 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
255 p, action->name);
256 p = ",";
257 }
258 raw_spin_unlock_irq(&desc->lock);
259
260 if (ret)
261 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
262
263 return ret;
264}
265IRQ_ATTR_RO(actions);
266
267static struct attribute *irq_attrs[] = {
268 &per_cpu_count_attr.attr,
269 &chip_name_attr.attr,
270 &hwirq_attr.attr,
271 &type_attr.attr,
272 &wakeup_attr.attr,
273 &name_attr.attr,
274 &actions_attr.attr,
275 NULL
276};
277
278static struct kobj_type irq_kobj_type = {
279 .release = irq_kobj_release,
280 .sysfs_ops = &kobj_sysfs_ops,
281 .default_attrs = irq_attrs,
282};
283
284static void irq_sysfs_add(int irq, struct irq_desc *desc)
285{
286 if (irq_kobj_base) {
287 /*
288 * Continue even in case of failure as this is nothing
289 * crucial.
290 */
291 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
292 pr_warn("Failed to add kobject for irq %d\n", irq);
293 }
294}
295
296static int __init irq_sysfs_init(void)
297{
298 struct irq_desc *desc;
299 int irq;
300
301 /* Prevent concurrent irq alloc/free */
302 irq_lock_sparse();
303
304 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
305 if (!irq_kobj_base) {
306 irq_unlock_sparse();
307 return -ENOMEM;
308 }
309
310 /* Add the already allocated interrupts */
311 for_each_irq_desc(irq, desc)
312 irq_sysfs_add(irq, desc);
313 irq_unlock_sparse();
314
315 return 0;
316}
317postcore_initcall(irq_sysfs_init);
318
319#else /* !CONFIG_SYSFS */
320
321static struct kobj_type irq_kobj_type = {
322 .release = irq_kobj_release,
323};
324
325static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
326
327#endif /* CONFIG_SYSFS */
328
329static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
330
331static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
332{
333 radix_tree_insert(&irq_desc_tree, irq, desc);
334}
335
336struct irq_desc *irq_to_desc(unsigned int irq)
337{
338 return radix_tree_lookup(&irq_desc_tree, irq);
339}
340EXPORT_SYMBOL(irq_to_desc);
341
342static void delete_irq_desc(unsigned int irq)
343{
344 radix_tree_delete(&irq_desc_tree, irq);
345}
346
347#ifdef CONFIG_SMP
348static void free_masks(struct irq_desc *desc)
349{
350#ifdef CONFIG_GENERIC_PENDING_IRQ
351 free_cpumask_var(desc->pending_mask);
352#endif
353 free_cpumask_var(desc->irq_common_data.affinity);
354#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
355 free_cpumask_var(desc->irq_common_data.effective_affinity);
356#endif
357}
358#else
359static inline void free_masks(struct irq_desc *desc) { }
360#endif
361
362void irq_lock_sparse(void)
363{
364 mutex_lock(&sparse_irq_lock);
365}
366
367void irq_unlock_sparse(void)
368{
369 mutex_unlock(&sparse_irq_lock);
370}
371
372static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
373 const struct cpumask *affinity,
374 struct module *owner)
375{
376 struct irq_desc *desc;
377
378 desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
379 if (!desc)
380 return NULL;
381 /* allocate based on nr_cpu_ids */
382 desc->kstat_irqs = alloc_percpu(unsigned int);
383 if (!desc->kstat_irqs)
384 goto err_desc;
385
386 if (alloc_masks(desc, node))
387 goto err_kstat;
388
389 raw_spin_lock_init(&desc->lock);
390 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
391 mutex_init(&desc->request_mutex);
392 init_rcu_head(&desc->rcu);
393
394 desc_set_defaults(irq, desc, node, affinity, owner);
395 irqd_set(&desc->irq_data, flags);
396 kobject_init(&desc->kobj, &irq_kobj_type);
397
398 return desc;
399
400err_kstat:
401 free_percpu(desc->kstat_irqs);
402err_desc:
403 kfree(desc);
404 return NULL;
405}
406
407static void irq_kobj_release(struct kobject *kobj)
408{
409 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
410
411 free_masks(desc);
412 free_percpu(desc->kstat_irqs);
413 kfree(desc);
414}
415
416static void delayed_free_desc(struct rcu_head *rhp)
417{
418 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
419
420 kobject_put(&desc->kobj);
421}
422
423static void free_desc(unsigned int irq)
424{
425 struct irq_desc *desc = irq_to_desc(irq);
426
427 irq_remove_debugfs_entry(desc);
428 unregister_irq_proc(irq, desc);
429
430 /*
431 * sparse_irq_lock protects also show_interrupts() and
432 * kstat_irq_usr(). Once we deleted the descriptor from the
433 * sparse tree we can free it. Access in proc will fail to
434 * lookup the descriptor.
435 *
436 * The sysfs entry must be serialized against a concurrent
437 * irq_sysfs_init() as well.
438 */
439 kobject_del(&desc->kobj);
440 delete_irq_desc(irq);
441
442 /*
443 * We free the descriptor, masks and stat fields via RCU. That
444 * allows demultiplex interrupts to do rcu based management of
445 * the child interrupts.
446 */
447 call_rcu(&desc->rcu, delayed_free_desc);
448}
449
450static int alloc_descs(unsigned int start, unsigned int cnt, int node,
451 const struct cpumask *affinity, struct module *owner)
452{
453 const struct cpumask *mask = NULL;
454 struct irq_desc *desc;
455 unsigned int flags;
456 int i;
457
458 /* Validate affinity mask(s) */
459 if (affinity) {
460 for (i = 0, mask = affinity; i < cnt; i++, mask++) {
461 if (cpumask_empty(mask))
462 return -EINVAL;
463 }
464 }
465
466 flags = affinity ? IRQD_AFFINITY_MANAGED | IRQD_MANAGED_SHUTDOWN : 0;
467 mask = NULL;
468
469 for (i = 0; i < cnt; i++) {
470 if (affinity) {
471 node = cpu_to_node(cpumask_first(affinity));
472 mask = affinity;
473 affinity++;
474 }
475 desc = alloc_desc(start + i, node, flags, mask, owner);
476 if (!desc)
477 goto err;
478 irq_insert_desc(start + i, desc);
479 irq_sysfs_add(start + i, desc);
480 irq_add_debugfs_entry(start + i, desc);
481 }
482 bitmap_set(allocated_irqs, start, cnt);
483 return start;
484
485err:
486 for (i--; i >= 0; i--)
487 free_desc(start + i);
488 return -ENOMEM;
489}
490
491static int irq_expand_nr_irqs(unsigned int nr)
492{
493 if (nr > IRQ_BITMAP_BITS)
494 return -ENOMEM;
495 nr_irqs = nr;
496 return 0;
497}
498
499int __init early_irq_init(void)
500{
501 int i, initcnt, node = first_online_node;
502 struct irq_desc *desc;
503
504 init_irq_default_affinity();
505
506 /* Let arch update nr_irqs and return the nr of preallocated irqs */
507 initcnt = arch_probe_nr_irqs();
508 printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
509 NR_IRQS, nr_irqs, initcnt);
510
511 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
512 nr_irqs = IRQ_BITMAP_BITS;
513
514 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
515 initcnt = IRQ_BITMAP_BITS;
516
517 if (initcnt > nr_irqs)
518 nr_irqs = initcnt;
519
520 for (i = 0; i < initcnt; i++) {
521 desc = alloc_desc(i, node, 0, NULL, NULL);
522 set_bit(i, allocated_irqs);
523 irq_insert_desc(i, desc);
524 }
525 return arch_early_irq_init();
526}
527
528#else /* !CONFIG_SPARSE_IRQ */
529
530struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
531 [0 ... NR_IRQS-1] = {
532 .handle_irq = handle_bad_irq,
533 .depth = 1,
534 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
535 }
536};
537
538int __init early_irq_init(void)
539{
540 int count, i, node = first_online_node;
541 struct irq_desc *desc;
542
543 init_irq_default_affinity();
544
545 printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
546
547 desc = irq_desc;
548 count = ARRAY_SIZE(irq_desc);
549
550 for (i = 0; i < count; i++) {
551 desc[i].kstat_irqs = alloc_percpu(unsigned int);
552 alloc_masks(&desc[i], node);
553 raw_spin_lock_init(&desc[i].lock);
554 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
555 desc_set_defaults(i, &desc[i], node, NULL, NULL);
556 }
557 return arch_early_irq_init();
558}
559
560struct irq_desc *irq_to_desc(unsigned int irq)
561{
562 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
563}
564EXPORT_SYMBOL(irq_to_desc);
565
566static void free_desc(unsigned int irq)
567{
568 struct irq_desc *desc = irq_to_desc(irq);
569 unsigned long flags;
570
571 raw_spin_lock_irqsave(&desc->lock, flags);
572 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
573 raw_spin_unlock_irqrestore(&desc->lock, flags);
574}
575
576static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
577 const struct cpumask *affinity,
578 struct module *owner)
579{
580 u32 i;
581
582 for (i = 0; i < cnt; i++) {
583 struct irq_desc *desc = irq_to_desc(start + i);
584
585 desc->owner = owner;
586 }
587 bitmap_set(allocated_irqs, start, cnt);
588 return start;
589}
590
591static int irq_expand_nr_irqs(unsigned int nr)
592{
593 return -ENOMEM;
594}
595
596void irq_mark_irq(unsigned int irq)
597{
598 mutex_lock(&sparse_irq_lock);
599 bitmap_set(allocated_irqs, irq, 1);
600 mutex_unlock(&sparse_irq_lock);
601}
602
603#ifdef CONFIG_GENERIC_IRQ_LEGACY
604void irq_init_desc(unsigned int irq)
605{
606 free_desc(irq);
607}
608#endif
609
610#endif /* !CONFIG_SPARSE_IRQ */
611
612/**
613 * generic_handle_irq - Invoke the handler for a particular irq
614 * @irq: The irq number to handle
615 *
616 */
617int generic_handle_irq(unsigned int irq)
618{
619 struct irq_desc *desc = irq_to_desc(irq);
620
621 if (!desc)
622 return -EINVAL;
623 generic_handle_irq_desc(desc);
624 return 0;
625}
626EXPORT_SYMBOL_GPL(generic_handle_irq);
627
628#ifdef CONFIG_HANDLE_DOMAIN_IRQ
629/**
630 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
631 * @domain: The domain where to perform the lookup
632 * @hwirq: The HW irq number to convert to a logical one
633 * @lookup: Whether to perform the domain lookup or not
634 * @regs: Register file coming from the low-level handling code
635 *
636 * Returns: 0 on success, or -EINVAL if conversion has failed
637 */
638int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
639 bool lookup, struct pt_regs *regs)
640{
641 struct pt_regs *old_regs = set_irq_regs(regs);
642 unsigned int irq = hwirq;
643 int ret = 0;
644
645 irq_enter();
646
647#ifdef CONFIG_IRQ_DOMAIN
648 if (lookup)
649 irq = irq_find_mapping(domain, hwirq);
650#endif
651
652 /*
653 * Some hardware gives randomly wrong interrupts. Rather
654 * than crashing, do something sensible.
655 */
656 if (unlikely(!irq || irq >= nr_irqs)) {
657 ack_bad_irq(irq);
658 ret = -EINVAL;
659 } else {
660 generic_handle_irq(irq);
661 }
662
663 irq_exit();
664 set_irq_regs(old_regs);
665 return ret;
666}
667#endif
668
669/* Dynamic interrupt handling */
670
671/**
672 * irq_free_descs - free irq descriptors
673 * @from: Start of descriptor range
674 * @cnt: Number of consecutive irqs to free
675 */
676void irq_free_descs(unsigned int from, unsigned int cnt)
677{
678 int i;
679
680 if (from >= nr_irqs || (from + cnt) > nr_irqs)
681 return;
682
683 mutex_lock(&sparse_irq_lock);
684 for (i = 0; i < cnt; i++)
685 free_desc(from + i);
686
687 bitmap_clear(allocated_irqs, from, cnt);
688 mutex_unlock(&sparse_irq_lock);
689}
690EXPORT_SYMBOL_GPL(irq_free_descs);
691
692/**
693 * irq_alloc_descs - allocate and initialize a range of irq descriptors
694 * @irq: Allocate for specific irq number if irq >= 0
695 * @from: Start the search from this irq number
696 * @cnt: Number of consecutive irqs to allocate.
697 * @node: Preferred node on which the irq descriptor should be allocated
698 * @owner: Owning module (can be NULL)
699 * @affinity: Optional pointer to an affinity mask array of size @cnt which
700 * hints where the irq descriptors should be allocated and which
701 * default affinities to use
702 *
703 * Returns the first irq number or error code
704 */
705int __ref
706__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
707 struct module *owner, const struct cpumask *affinity)
708{
709 int start, ret;
710
711 if (!cnt)
712 return -EINVAL;
713
714 if (irq >= 0) {
715 if (from > irq)
716 return -EINVAL;
717 from = irq;
718 } else {
719 /*
720 * For interrupts which are freely allocated the
721 * architecture can force a lower bound to the @from
722 * argument. x86 uses this to exclude the GSI space.
723 */
724 from = arch_dynirq_lower_bound(from);
725 }
726
727 mutex_lock(&sparse_irq_lock);
728
729 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
730 from, cnt, 0);
731 ret = -EEXIST;
732 if (irq >=0 && start != irq)
733 goto unlock;
734
735 if (start + cnt > nr_irqs) {
736 ret = irq_expand_nr_irqs(start + cnt);
737 if (ret)
738 goto unlock;
739 }
740 ret = alloc_descs(start, cnt, node, affinity, owner);
741unlock:
742 mutex_unlock(&sparse_irq_lock);
743 return ret;
744}
745EXPORT_SYMBOL_GPL(__irq_alloc_descs);
746
747#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
748/**
749 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
750 * @cnt: number of interrupts to allocate
751 * @node: node on which to allocate
752 *
753 * Returns an interrupt number > 0 or 0, if the allocation fails.
754 */
755unsigned int irq_alloc_hwirqs(int cnt, int node)
756{
757 int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL);
758
759 if (irq < 0)
760 return 0;
761
762 for (i = irq; cnt > 0; i++, cnt--) {
763 if (arch_setup_hwirq(i, node))
764 goto err;
765 irq_clear_status_flags(i, _IRQ_NOREQUEST);
766 }
767 return irq;
768
769err:
770 for (i--; i >= irq; i--) {
771 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
772 arch_teardown_hwirq(i);
773 }
774 irq_free_descs(irq, cnt);
775 return 0;
776}
777EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
778
779/**
780 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
781 * @from: Free from irq number
782 * @cnt: number of interrupts to free
783 *
784 */
785void irq_free_hwirqs(unsigned int from, int cnt)
786{
787 int i, j;
788
789 for (i = from, j = cnt; j > 0; i++, j--) {
790 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
791 arch_teardown_hwirq(i);
792 }
793 irq_free_descs(from, cnt);
794}
795EXPORT_SYMBOL_GPL(irq_free_hwirqs);
796#endif
797
798/**
799 * irq_get_next_irq - get next allocated irq number
800 * @offset: where to start the search
801 *
802 * Returns next irq number after offset or nr_irqs if none is found.
803 */
804unsigned int irq_get_next_irq(unsigned int offset)
805{
806 return find_next_bit(allocated_irqs, nr_irqs, offset);
807}
808
809struct irq_desc *
810__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
811 unsigned int check)
812{
813 struct irq_desc *desc = irq_to_desc(irq);
814
815 if (desc) {
816 if (check & _IRQ_DESC_CHECK) {
817 if ((check & _IRQ_DESC_PERCPU) &&
818 !irq_settings_is_per_cpu_devid(desc))
819 return NULL;
820
821 if (!(check & _IRQ_DESC_PERCPU) &&
822 irq_settings_is_per_cpu_devid(desc))
823 return NULL;
824 }
825
826 if (bus)
827 chip_bus_lock(desc);
828 raw_spin_lock_irqsave(&desc->lock, *flags);
829 }
830 return desc;
831}
832
833void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
834{
835 raw_spin_unlock_irqrestore(&desc->lock, flags);
836 if (bus)
837 chip_bus_sync_unlock(desc);
838}
839
840int irq_set_percpu_devid_partition(unsigned int irq,
841 const struct cpumask *affinity)
842{
843 struct irq_desc *desc = irq_to_desc(irq);
844
845 if (!desc)
846 return -EINVAL;
847
848 if (desc->percpu_enabled)
849 return -EINVAL;
850
851 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
852
853 if (!desc->percpu_enabled)
854 return -ENOMEM;
855
856 if (affinity)
857 desc->percpu_affinity = affinity;
858 else
859 desc->percpu_affinity = cpu_possible_mask;
860
861 irq_set_percpu_devid_flags(irq);
862 return 0;
863}
864
865int irq_set_percpu_devid(unsigned int irq)
866{
867 return irq_set_percpu_devid_partition(irq, NULL);
868}
869
870int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
871{
872 struct irq_desc *desc = irq_to_desc(irq);
873
874 if (!desc || !desc->percpu_enabled)
875 return -EINVAL;
876
877 if (affinity)
878 cpumask_copy(affinity, desc->percpu_affinity);
879
880 return 0;
881}
882EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
883
884void kstat_incr_irq_this_cpu(unsigned int irq)
885{
886 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
887}
888
889/**
890 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
891 * @irq: The interrupt number
892 * @cpu: The cpu number
893 *
894 * Returns the sum of interrupt counts on @cpu since boot for
895 * @irq. The caller must ensure that the interrupt is not removed
896 * concurrently.
897 */
898unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
899{
900 struct irq_desc *desc = irq_to_desc(irq);
901
902 return desc && desc->kstat_irqs ?
903 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
904}
905
906/**
907 * kstat_irqs - Get the statistics for an interrupt
908 * @irq: The interrupt number
909 *
910 * Returns the sum of interrupt counts on all cpus since boot for
911 * @irq. The caller must ensure that the interrupt is not removed
912 * concurrently.
913 */
914unsigned int kstat_irqs(unsigned int irq)
915{
916 struct irq_desc *desc = irq_to_desc(irq);
917 int cpu;
918 unsigned int sum = 0;
919
920 if (!desc || !desc->kstat_irqs)
921 return 0;
922 for_each_possible_cpu(cpu)
923 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
924 return sum;
925}
926
927/**
928 * kstat_irqs_usr - Get the statistics for an interrupt
929 * @irq: The interrupt number
930 *
931 * Returns the sum of interrupt counts on all cpus since boot for
932 * @irq. Contrary to kstat_irqs() this can be called from any
933 * preemptible context. It's protected against concurrent removal of
934 * an interrupt descriptor when sparse irqs are enabled.
935 */
936unsigned int kstat_irqs_usr(unsigned int irq)
937{
938 unsigned int sum;
939
940 irq_lock_sparse();
941 sum = kstat_irqs(irq);
942 irq_unlock_sparse();
943 return sum;
944}