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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/maple_tree.h>
16#include <linux/irqdomain.h>
17#include <linux/sysfs.h>
18
19#include "internals.h"
20
21/*
22 * lockdep: we want to handle all irq_desc locks as a single lock-class:
23 */
24static struct lock_class_key irq_desc_lock_class;
25
26#if defined(CONFIG_SMP)
27static int __init irq_affinity_setup(char *str)
28{
29 alloc_bootmem_cpumask_var(&irq_default_affinity);
30 cpulist_parse(str, irq_default_affinity);
31 /*
32 * Set at least the boot cpu. We don't want to end up with
33 * bugreports caused by random commandline masks
34 */
35 cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
36 return 1;
37}
38__setup("irqaffinity=", irq_affinity_setup);
39
40static void __init init_irq_default_affinity(void)
41{
42 if (!cpumask_available(irq_default_affinity))
43 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
44 if (cpumask_empty(irq_default_affinity))
45 cpumask_setall(irq_default_affinity);
46}
47#else
48static void __init init_irq_default_affinity(void)
49{
50}
51#endif
52
53#ifdef CONFIG_SMP
54static int alloc_masks(struct irq_desc *desc, int node)
55{
56 if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
57 GFP_KERNEL, node))
58 return -ENOMEM;
59
60#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
61 if (!zalloc_cpumask_var_node(&desc->irq_common_data.effective_affinity,
62 GFP_KERNEL, node)) {
63 free_cpumask_var(desc->irq_common_data.affinity);
64 return -ENOMEM;
65 }
66#endif
67
68#ifdef CONFIG_GENERIC_PENDING_IRQ
69 if (!zalloc_cpumask_var_node(&desc->pending_mask, GFP_KERNEL, node)) {
70#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
71 free_cpumask_var(desc->irq_common_data.effective_affinity);
72#endif
73 free_cpumask_var(desc->irq_common_data.affinity);
74 return -ENOMEM;
75 }
76#endif
77 return 0;
78}
79
80static void desc_smp_init(struct irq_desc *desc, int node,
81 const struct cpumask *affinity)
82{
83 if (!affinity)
84 affinity = irq_default_affinity;
85 cpumask_copy(desc->irq_common_data.affinity, affinity);
86
87#ifdef CONFIG_GENERIC_PENDING_IRQ
88 cpumask_clear(desc->pending_mask);
89#endif
90#ifdef CONFIG_NUMA
91 desc->irq_common_data.node = node;
92#endif
93}
94
95static void free_masks(struct irq_desc *desc)
96{
97#ifdef CONFIG_GENERIC_PENDING_IRQ
98 free_cpumask_var(desc->pending_mask);
99#endif
100 free_cpumask_var(desc->irq_common_data.affinity);
101#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
102 free_cpumask_var(desc->irq_common_data.effective_affinity);
103#endif
104}
105
106#else
107static inline int
108alloc_masks(struct irq_desc *desc, int node) { return 0; }
109static inline void
110desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
111static inline void free_masks(struct irq_desc *desc) { }
112#endif
113
114static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
115 const struct cpumask *affinity, struct module *owner)
116{
117 int cpu;
118
119 desc->irq_common_data.handler_data = NULL;
120 desc->irq_common_data.msi_desc = NULL;
121
122 desc->irq_data.common = &desc->irq_common_data;
123 desc->irq_data.irq = irq;
124 desc->irq_data.chip = &no_irq_chip;
125 desc->irq_data.chip_data = NULL;
126 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
127 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
128 irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
129 desc->handle_irq = handle_bad_irq;
130 desc->depth = 1;
131 desc->irq_count = 0;
132 desc->irqs_unhandled = 0;
133 desc->tot_count = 0;
134 desc->name = NULL;
135 desc->owner = owner;
136 for_each_possible_cpu(cpu)
137 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
138 desc_smp_init(desc, node, affinity);
139}
140
141int nr_irqs = NR_IRQS;
142EXPORT_SYMBOL_GPL(nr_irqs);
143
144static DEFINE_MUTEX(sparse_irq_lock);
145static struct maple_tree sparse_irqs = MTREE_INIT_EXT(sparse_irqs,
146 MT_FLAGS_ALLOC_RANGE |
147 MT_FLAGS_LOCK_EXTERN |
148 MT_FLAGS_USE_RCU,
149 sparse_irq_lock);
150
151static int irq_find_free_area(unsigned int from, unsigned int cnt)
152{
153 MA_STATE(mas, &sparse_irqs, 0, 0);
154
155 if (mas_empty_area(&mas, from, MAX_SPARSE_IRQS, cnt))
156 return -ENOSPC;
157 return mas.index;
158}
159
160static unsigned int irq_find_at_or_after(unsigned int offset)
161{
162 unsigned long index = offset;
163 struct irq_desc *desc = mt_find(&sparse_irqs, &index, nr_irqs);
164
165 return desc ? irq_desc_get_irq(desc) : nr_irqs;
166}
167
168static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
169{
170 MA_STATE(mas, &sparse_irqs, irq, irq);
171 WARN_ON(mas_store_gfp(&mas, desc, GFP_KERNEL) != 0);
172}
173
174static void delete_irq_desc(unsigned int irq)
175{
176 MA_STATE(mas, &sparse_irqs, irq, irq);
177 mas_erase(&mas);
178}
179
180#ifdef CONFIG_SPARSE_IRQ
181static const struct kobj_type irq_kobj_type;
182#endif
183
184static int init_desc(struct irq_desc *desc, int irq, int node,
185 unsigned int flags,
186 const struct cpumask *affinity,
187 struct module *owner)
188{
189 desc->kstat_irqs = alloc_percpu(unsigned int);
190 if (!desc->kstat_irqs)
191 return -ENOMEM;
192
193 if (alloc_masks(desc, node)) {
194 free_percpu(desc->kstat_irqs);
195 return -ENOMEM;
196 }
197
198 raw_spin_lock_init(&desc->lock);
199 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
200 mutex_init(&desc->request_mutex);
201 init_waitqueue_head(&desc->wait_for_threads);
202 desc_set_defaults(irq, desc, node, affinity, owner);
203 irqd_set(&desc->irq_data, flags);
204 irq_resend_init(desc);
205#ifdef CONFIG_SPARSE_IRQ
206 kobject_init(&desc->kobj, &irq_kobj_type);
207 init_rcu_head(&desc->rcu);
208#endif
209
210 return 0;
211}
212
213#ifdef CONFIG_SPARSE_IRQ
214
215static void irq_kobj_release(struct kobject *kobj);
216
217#ifdef CONFIG_SYSFS
218static struct kobject *irq_kobj_base;
219
220#define IRQ_ATTR_RO(_name) \
221static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
222
223static ssize_t per_cpu_count_show(struct kobject *kobj,
224 struct kobj_attribute *attr, char *buf)
225{
226 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
227 ssize_t ret = 0;
228 char *p = "";
229 int cpu;
230
231 for_each_possible_cpu(cpu) {
232 unsigned int c = irq_desc_kstat_cpu(desc, cpu);
233
234 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
235 p = ",";
236 }
237
238 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
239 return ret;
240}
241IRQ_ATTR_RO(per_cpu_count);
242
243static ssize_t chip_name_show(struct kobject *kobj,
244 struct kobj_attribute *attr, char *buf)
245{
246 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
247 ssize_t ret = 0;
248
249 raw_spin_lock_irq(&desc->lock);
250 if (desc->irq_data.chip && desc->irq_data.chip->name) {
251 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
252 desc->irq_data.chip->name);
253 }
254 raw_spin_unlock_irq(&desc->lock);
255
256 return ret;
257}
258IRQ_ATTR_RO(chip_name);
259
260static ssize_t hwirq_show(struct kobject *kobj,
261 struct kobj_attribute *attr, char *buf)
262{
263 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
264 ssize_t ret = 0;
265
266 raw_spin_lock_irq(&desc->lock);
267 if (desc->irq_data.domain)
268 ret = sprintf(buf, "%lu\n", desc->irq_data.hwirq);
269 raw_spin_unlock_irq(&desc->lock);
270
271 return ret;
272}
273IRQ_ATTR_RO(hwirq);
274
275static ssize_t type_show(struct kobject *kobj,
276 struct kobj_attribute *attr, char *buf)
277{
278 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
279 ssize_t ret = 0;
280
281 raw_spin_lock_irq(&desc->lock);
282 ret = sprintf(buf, "%s\n",
283 irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
284 raw_spin_unlock_irq(&desc->lock);
285
286 return ret;
287
288}
289IRQ_ATTR_RO(type);
290
291static ssize_t wakeup_show(struct kobject *kobj,
292 struct kobj_attribute *attr, char *buf)
293{
294 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
295 ssize_t ret = 0;
296
297 raw_spin_lock_irq(&desc->lock);
298 ret = sprintf(buf, "%s\n",
299 irqd_is_wakeup_set(&desc->irq_data) ? "enabled" : "disabled");
300 raw_spin_unlock_irq(&desc->lock);
301
302 return ret;
303
304}
305IRQ_ATTR_RO(wakeup);
306
307static ssize_t name_show(struct kobject *kobj,
308 struct kobj_attribute *attr, char *buf)
309{
310 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
311 ssize_t ret = 0;
312
313 raw_spin_lock_irq(&desc->lock);
314 if (desc->name)
315 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
316 raw_spin_unlock_irq(&desc->lock);
317
318 return ret;
319}
320IRQ_ATTR_RO(name);
321
322static ssize_t actions_show(struct kobject *kobj,
323 struct kobj_attribute *attr, char *buf)
324{
325 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
326 struct irqaction *action;
327 ssize_t ret = 0;
328 char *p = "";
329
330 raw_spin_lock_irq(&desc->lock);
331 for_each_action_of_desc(desc, action) {
332 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
333 p, action->name);
334 p = ",";
335 }
336 raw_spin_unlock_irq(&desc->lock);
337
338 if (ret)
339 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
340
341 return ret;
342}
343IRQ_ATTR_RO(actions);
344
345static struct attribute *irq_attrs[] = {
346 &per_cpu_count_attr.attr,
347 &chip_name_attr.attr,
348 &hwirq_attr.attr,
349 &type_attr.attr,
350 &wakeup_attr.attr,
351 &name_attr.attr,
352 &actions_attr.attr,
353 NULL
354};
355ATTRIBUTE_GROUPS(irq);
356
357static const struct kobj_type irq_kobj_type = {
358 .release = irq_kobj_release,
359 .sysfs_ops = &kobj_sysfs_ops,
360 .default_groups = irq_groups,
361};
362
363static void irq_sysfs_add(int irq, struct irq_desc *desc)
364{
365 if (irq_kobj_base) {
366 /*
367 * Continue even in case of failure as this is nothing
368 * crucial and failures in the late irq_sysfs_init()
369 * cannot be rolled back.
370 */
371 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
372 pr_warn("Failed to add kobject for irq %d\n", irq);
373 else
374 desc->istate |= IRQS_SYSFS;
375 }
376}
377
378static void irq_sysfs_del(struct irq_desc *desc)
379{
380 /*
381 * Only invoke kobject_del() when kobject_add() was successfully
382 * invoked for the descriptor. This covers both early boot, where
383 * sysfs is not initialized yet, and the case of a failed
384 * kobject_add() invocation.
385 */
386 if (desc->istate & IRQS_SYSFS)
387 kobject_del(&desc->kobj);
388}
389
390static int __init irq_sysfs_init(void)
391{
392 struct irq_desc *desc;
393 int irq;
394
395 /* Prevent concurrent irq alloc/free */
396 irq_lock_sparse();
397
398 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
399 if (!irq_kobj_base) {
400 irq_unlock_sparse();
401 return -ENOMEM;
402 }
403
404 /* Add the already allocated interrupts */
405 for_each_irq_desc(irq, desc)
406 irq_sysfs_add(irq, desc);
407 irq_unlock_sparse();
408
409 return 0;
410}
411postcore_initcall(irq_sysfs_init);
412
413#else /* !CONFIG_SYSFS */
414
415static const struct kobj_type irq_kobj_type = {
416 .release = irq_kobj_release,
417};
418
419static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
420static void irq_sysfs_del(struct irq_desc *desc) {}
421
422#endif /* CONFIG_SYSFS */
423
424struct irq_desc *irq_to_desc(unsigned int irq)
425{
426 return mtree_load(&sparse_irqs, irq);
427}
428#ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
429EXPORT_SYMBOL_GPL(irq_to_desc);
430#endif
431
432void irq_lock_sparse(void)
433{
434 mutex_lock(&sparse_irq_lock);
435}
436
437void irq_unlock_sparse(void)
438{
439 mutex_unlock(&sparse_irq_lock);
440}
441
442static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
443 const struct cpumask *affinity,
444 struct module *owner)
445{
446 struct irq_desc *desc;
447 int ret;
448
449 desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
450 if (!desc)
451 return NULL;
452
453 ret = init_desc(desc, irq, node, flags, affinity, owner);
454 if (unlikely(ret)) {
455 kfree(desc);
456 return NULL;
457 }
458
459 return desc;
460}
461
462static void irq_kobj_release(struct kobject *kobj)
463{
464 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
465
466 free_masks(desc);
467 free_percpu(desc->kstat_irqs);
468 kfree(desc);
469}
470
471static void delayed_free_desc(struct rcu_head *rhp)
472{
473 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
474
475 kobject_put(&desc->kobj);
476}
477
478static void free_desc(unsigned int irq)
479{
480 struct irq_desc *desc = irq_to_desc(irq);
481
482 irq_remove_debugfs_entry(desc);
483 unregister_irq_proc(irq, desc);
484
485 /*
486 * sparse_irq_lock protects also show_interrupts() and
487 * kstat_irq_usr(). Once we deleted the descriptor from the
488 * sparse tree we can free it. Access in proc will fail to
489 * lookup the descriptor.
490 *
491 * The sysfs entry must be serialized against a concurrent
492 * irq_sysfs_init() as well.
493 */
494 irq_sysfs_del(desc);
495 delete_irq_desc(irq);
496
497 /*
498 * We free the descriptor, masks and stat fields via RCU. That
499 * allows demultiplex interrupts to do rcu based management of
500 * the child interrupts.
501 * This also allows us to use rcu in kstat_irqs_usr().
502 */
503 call_rcu(&desc->rcu, delayed_free_desc);
504}
505
506static int alloc_descs(unsigned int start, unsigned int cnt, int node,
507 const struct irq_affinity_desc *affinity,
508 struct module *owner)
509{
510 struct irq_desc *desc;
511 int i;
512
513 /* Validate affinity mask(s) */
514 if (affinity) {
515 for (i = 0; i < cnt; i++) {
516 if (cpumask_empty(&affinity[i].mask))
517 return -EINVAL;
518 }
519 }
520
521 for (i = 0; i < cnt; i++) {
522 const struct cpumask *mask = NULL;
523 unsigned int flags = 0;
524
525 if (affinity) {
526 if (affinity->is_managed) {
527 flags = IRQD_AFFINITY_MANAGED |
528 IRQD_MANAGED_SHUTDOWN;
529 }
530 mask = &affinity->mask;
531 node = cpu_to_node(cpumask_first(mask));
532 affinity++;
533 }
534
535 desc = alloc_desc(start + i, node, flags, mask, owner);
536 if (!desc)
537 goto err;
538 irq_insert_desc(start + i, desc);
539 irq_sysfs_add(start + i, desc);
540 irq_add_debugfs_entry(start + i, desc);
541 }
542 return start;
543
544err:
545 for (i--; i >= 0; i--)
546 free_desc(start + i);
547 return -ENOMEM;
548}
549
550static int irq_expand_nr_irqs(unsigned int nr)
551{
552 if (nr > MAX_SPARSE_IRQS)
553 return -ENOMEM;
554 nr_irqs = nr;
555 return 0;
556}
557
558int __init early_irq_init(void)
559{
560 int i, initcnt, node = first_online_node;
561 struct irq_desc *desc;
562
563 init_irq_default_affinity();
564
565 /* Let arch update nr_irqs and return the nr of preallocated irqs */
566 initcnt = arch_probe_nr_irqs();
567 printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
568 NR_IRQS, nr_irqs, initcnt);
569
570 if (WARN_ON(nr_irqs > MAX_SPARSE_IRQS))
571 nr_irqs = MAX_SPARSE_IRQS;
572
573 if (WARN_ON(initcnt > MAX_SPARSE_IRQS))
574 initcnt = MAX_SPARSE_IRQS;
575
576 if (initcnt > nr_irqs)
577 nr_irqs = initcnt;
578
579 for (i = 0; i < initcnt; i++) {
580 desc = alloc_desc(i, node, 0, NULL, NULL);
581 irq_insert_desc(i, desc);
582 }
583 return arch_early_irq_init();
584}
585
586#else /* !CONFIG_SPARSE_IRQ */
587
588struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
589 [0 ... NR_IRQS-1] = {
590 .handle_irq = handle_bad_irq,
591 .depth = 1,
592 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
593 }
594};
595
596int __init early_irq_init(void)
597{
598 int count, i, node = first_online_node;
599 int ret;
600
601 init_irq_default_affinity();
602
603 printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
604
605 count = ARRAY_SIZE(irq_desc);
606
607 for (i = 0; i < count; i++) {
608 ret = init_desc(irq_desc + i, i, node, 0, NULL, NULL);
609 if (unlikely(ret))
610 goto __free_desc_res;
611 }
612
613 return arch_early_irq_init();
614
615__free_desc_res:
616 while (--i >= 0) {
617 free_masks(irq_desc + i);
618 free_percpu(irq_desc[i].kstat_irqs);
619 }
620
621 return ret;
622}
623
624struct irq_desc *irq_to_desc(unsigned int irq)
625{
626 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
627}
628EXPORT_SYMBOL(irq_to_desc);
629
630static void free_desc(unsigned int irq)
631{
632 struct irq_desc *desc = irq_to_desc(irq);
633 unsigned long flags;
634
635 raw_spin_lock_irqsave(&desc->lock, flags);
636 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
637 raw_spin_unlock_irqrestore(&desc->lock, flags);
638 delete_irq_desc(irq);
639}
640
641static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
642 const struct irq_affinity_desc *affinity,
643 struct module *owner)
644{
645 u32 i;
646
647 for (i = 0; i < cnt; i++) {
648 struct irq_desc *desc = irq_to_desc(start + i);
649
650 desc->owner = owner;
651 irq_insert_desc(start + i, desc);
652 }
653 return start;
654}
655
656static int irq_expand_nr_irqs(unsigned int nr)
657{
658 return -ENOMEM;
659}
660
661void irq_mark_irq(unsigned int irq)
662{
663 mutex_lock(&sparse_irq_lock);
664 irq_insert_desc(irq, irq_desc + irq);
665 mutex_unlock(&sparse_irq_lock);
666}
667
668#ifdef CONFIG_GENERIC_IRQ_LEGACY
669void irq_init_desc(unsigned int irq)
670{
671 free_desc(irq);
672}
673#endif
674
675#endif /* !CONFIG_SPARSE_IRQ */
676
677int handle_irq_desc(struct irq_desc *desc)
678{
679 struct irq_data *data;
680
681 if (!desc)
682 return -EINVAL;
683
684 data = irq_desc_get_irq_data(desc);
685 if (WARN_ON_ONCE(!in_hardirq() && handle_enforce_irqctx(data)))
686 return -EPERM;
687
688 generic_handle_irq_desc(desc);
689 return 0;
690}
691
692/**
693 * generic_handle_irq - Invoke the handler for a particular irq
694 * @irq: The irq number to handle
695 *
696 * Returns: 0 on success, or -EINVAL if conversion has failed
697 *
698 * This function must be called from an IRQ context with irq regs
699 * initialized.
700 */
701int generic_handle_irq(unsigned int irq)
702{
703 return handle_irq_desc(irq_to_desc(irq));
704}
705EXPORT_SYMBOL_GPL(generic_handle_irq);
706
707/**
708 * generic_handle_irq_safe - Invoke the handler for a particular irq from any
709 * context.
710 * @irq: The irq number to handle
711 *
712 * Returns: 0 on success, a negative value on error.
713 *
714 * This function can be called from any context (IRQ or process context). It
715 * will report an error if not invoked from IRQ context and the irq has been
716 * marked to enforce IRQ-context only.
717 */
718int generic_handle_irq_safe(unsigned int irq)
719{
720 unsigned long flags;
721 int ret;
722
723 local_irq_save(flags);
724 ret = handle_irq_desc(irq_to_desc(irq));
725 local_irq_restore(flags);
726 return ret;
727}
728EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
729
730#ifdef CONFIG_IRQ_DOMAIN
731/**
732 * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
733 * to a domain.
734 * @domain: The domain where to perform the lookup
735 * @hwirq: The HW irq number to convert to a logical one
736 *
737 * Returns: 0 on success, or -EINVAL if conversion has failed
738 *
739 * This function must be called from an IRQ context with irq regs
740 * initialized.
741 */
742int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
743{
744 return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
745}
746EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
747
748 /**
749 * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
750 * to a domain from any context.
751 * @domain: The domain where to perform the lookup
752 * @hwirq: The HW irq number to convert to a logical one
753 *
754 * Returns: 0 on success, a negative value on error.
755 *
756 * This function can be called from any context (IRQ or process
757 * context). If the interrupt is marked as 'enforce IRQ-context only' then
758 * the function must be invoked from hard interrupt context.
759 */
760int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
761{
762 unsigned long flags;
763 int ret;
764
765 local_irq_save(flags);
766 ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
767 local_irq_restore(flags);
768 return ret;
769}
770EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
771
772/**
773 * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
774 * to a domain.
775 * @domain: The domain where to perform the lookup
776 * @hwirq: The HW irq number to convert to a logical one
777 *
778 * Returns: 0 on success, or -EINVAL if conversion has failed
779 *
780 * This function must be called from an NMI context with irq regs
781 * initialized.
782 **/
783int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq)
784{
785 WARN_ON_ONCE(!in_nmi());
786 return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
787}
788#endif
789
790/* Dynamic interrupt handling */
791
792/**
793 * irq_free_descs - free irq descriptors
794 * @from: Start of descriptor range
795 * @cnt: Number of consecutive irqs to free
796 */
797void irq_free_descs(unsigned int from, unsigned int cnt)
798{
799 int i;
800
801 if (from >= nr_irqs || (from + cnt) > nr_irqs)
802 return;
803
804 mutex_lock(&sparse_irq_lock);
805 for (i = 0; i < cnt; i++)
806 free_desc(from + i);
807
808 mutex_unlock(&sparse_irq_lock);
809}
810EXPORT_SYMBOL_GPL(irq_free_descs);
811
812/**
813 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
814 * @irq: Allocate for specific irq number if irq >= 0
815 * @from: Start the search from this irq number
816 * @cnt: Number of consecutive irqs to allocate.
817 * @node: Preferred node on which the irq descriptor should be allocated
818 * @owner: Owning module (can be NULL)
819 * @affinity: Optional pointer to an affinity mask array of size @cnt which
820 * hints where the irq descriptors should be allocated and which
821 * default affinities to use
822 *
823 * Returns the first irq number or error code
824 */
825int __ref
826__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
827 struct module *owner, const struct irq_affinity_desc *affinity)
828{
829 int start, ret;
830
831 if (!cnt)
832 return -EINVAL;
833
834 if (irq >= 0) {
835 if (from > irq)
836 return -EINVAL;
837 from = irq;
838 } else {
839 /*
840 * For interrupts which are freely allocated the
841 * architecture can force a lower bound to the @from
842 * argument. x86 uses this to exclude the GSI space.
843 */
844 from = arch_dynirq_lower_bound(from);
845 }
846
847 mutex_lock(&sparse_irq_lock);
848
849 start = irq_find_free_area(from, cnt);
850 ret = -EEXIST;
851 if (irq >=0 && start != irq)
852 goto unlock;
853
854 if (start + cnt > nr_irqs) {
855 ret = irq_expand_nr_irqs(start + cnt);
856 if (ret)
857 goto unlock;
858 }
859 ret = alloc_descs(start, cnt, node, affinity, owner);
860unlock:
861 mutex_unlock(&sparse_irq_lock);
862 return ret;
863}
864EXPORT_SYMBOL_GPL(__irq_alloc_descs);
865
866/**
867 * irq_get_next_irq - get next allocated irq number
868 * @offset: where to start the search
869 *
870 * Returns next irq number after offset or nr_irqs if none is found.
871 */
872unsigned int irq_get_next_irq(unsigned int offset)
873{
874 return irq_find_at_or_after(offset);
875}
876
877struct irq_desc *
878__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
879 unsigned int check)
880{
881 struct irq_desc *desc = irq_to_desc(irq);
882
883 if (desc) {
884 if (check & _IRQ_DESC_CHECK) {
885 if ((check & _IRQ_DESC_PERCPU) &&
886 !irq_settings_is_per_cpu_devid(desc))
887 return NULL;
888
889 if (!(check & _IRQ_DESC_PERCPU) &&
890 irq_settings_is_per_cpu_devid(desc))
891 return NULL;
892 }
893
894 if (bus)
895 chip_bus_lock(desc);
896 raw_spin_lock_irqsave(&desc->lock, *flags);
897 }
898 return desc;
899}
900
901void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
902 __releases(&desc->lock)
903{
904 raw_spin_unlock_irqrestore(&desc->lock, flags);
905 if (bus)
906 chip_bus_sync_unlock(desc);
907}
908
909int irq_set_percpu_devid_partition(unsigned int irq,
910 const struct cpumask *affinity)
911{
912 struct irq_desc *desc = irq_to_desc(irq);
913
914 if (!desc)
915 return -EINVAL;
916
917 if (desc->percpu_enabled)
918 return -EINVAL;
919
920 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
921
922 if (!desc->percpu_enabled)
923 return -ENOMEM;
924
925 if (affinity)
926 desc->percpu_affinity = affinity;
927 else
928 desc->percpu_affinity = cpu_possible_mask;
929
930 irq_set_percpu_devid_flags(irq);
931 return 0;
932}
933
934int irq_set_percpu_devid(unsigned int irq)
935{
936 return irq_set_percpu_devid_partition(irq, NULL);
937}
938
939int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
940{
941 struct irq_desc *desc = irq_to_desc(irq);
942
943 if (!desc || !desc->percpu_enabled)
944 return -EINVAL;
945
946 if (affinity)
947 cpumask_copy(affinity, desc->percpu_affinity);
948
949 return 0;
950}
951EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
952
953void kstat_incr_irq_this_cpu(unsigned int irq)
954{
955 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
956}
957
958/**
959 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
960 * @irq: The interrupt number
961 * @cpu: The cpu number
962 *
963 * Returns the sum of interrupt counts on @cpu since boot for
964 * @irq. The caller must ensure that the interrupt is not removed
965 * concurrently.
966 */
967unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
968{
969 struct irq_desc *desc = irq_to_desc(irq);
970
971 return desc && desc->kstat_irqs ?
972 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
973}
974
975static bool irq_is_nmi(struct irq_desc *desc)
976{
977 return desc->istate & IRQS_NMI;
978}
979
980static unsigned int kstat_irqs(unsigned int irq)
981{
982 struct irq_desc *desc = irq_to_desc(irq);
983 unsigned int sum = 0;
984 int cpu;
985
986 if (!desc || !desc->kstat_irqs)
987 return 0;
988 if (!irq_settings_is_per_cpu_devid(desc) &&
989 !irq_settings_is_per_cpu(desc) &&
990 !irq_is_nmi(desc))
991 return data_race(desc->tot_count);
992
993 for_each_possible_cpu(cpu)
994 sum += data_race(*per_cpu_ptr(desc->kstat_irqs, cpu));
995 return sum;
996}
997
998/**
999 * kstat_irqs_usr - Get the statistics for an interrupt from thread context
1000 * @irq: The interrupt number
1001 *
1002 * Returns the sum of interrupt counts on all cpus since boot for @irq.
1003 *
1004 * It uses rcu to protect the access since a concurrent removal of an
1005 * interrupt descriptor is observing an rcu grace period before
1006 * delayed_free_desc()/irq_kobj_release().
1007 */
1008unsigned int kstat_irqs_usr(unsigned int irq)
1009{
1010 unsigned int sum;
1011
1012 rcu_read_lock();
1013 sum = kstat_irqs(irq);
1014 rcu_read_unlock();
1015 return sum;
1016}
1017
1018#ifdef CONFIG_LOCKDEP
1019void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
1020 struct lock_class_key *request_class)
1021{
1022 struct irq_desc *desc = irq_to_desc(irq);
1023
1024 if (desc) {
1025 lockdep_set_class(&desc->lock, lock_class);
1026 lockdep_set_class(&desc->request_mutex, request_class);
1027 }
1028}
1029EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1030#endif