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