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 */
25 static struct lock_class_key irq_desc_lock_class;
26
27 #if defined(CONFIG_SMP)
irq_affinity_setup(char * str)28 static 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
init_irq_default_affinity(void)41 static 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
init_irq_default_affinity(void)49 static void __init init_irq_default_affinity(void)
50 {
51 }
52 #endif
53
54 #ifdef CONFIG_SMP
alloc_masks(struct irq_desc * desc,int node)55 static 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
desc_smp_init(struct irq_desc * desc,int node,const struct cpumask * affinity)81 static 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
97 static inline int
alloc_masks(struct irq_desc * desc,int node)98 alloc_masks(struct irq_desc *desc, int node) { return 0; }
99 static inline void
desc_smp_init(struct irq_desc * desc,int node,const struct cpumask * affinity)100 desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
101 #endif
102
desc_set_defaults(unsigned int irq,struct irq_desc * desc,int node,const struct cpumask * affinity,struct module * owner)103 static 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
129 int nr_irqs = NR_IRQS;
130 EXPORT_SYMBOL_GPL(nr_irqs);
131
132 static DEFINE_MUTEX(sparse_irq_lock);
133 static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
134
135 #ifdef CONFIG_SPARSE_IRQ
136
137 static void irq_kobj_release(struct kobject *kobj);
138
139 #ifdef CONFIG_SYSFS
140 static struct kobject *irq_kobj_base;
141
142 #define IRQ_ATTR_RO(_name) \
143 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
144
per_cpu_count_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)145 static 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 }
163 IRQ_ATTR_RO(per_cpu_count);
164
chip_name_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)165 static 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 }
180 IRQ_ATTR_RO(chip_name);
181
hwirq_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)182 static 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 }
195 IRQ_ATTR_RO(hwirq);
196
type_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)197 static 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 }
211 IRQ_ATTR_RO(type);
212
wakeup_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)213 static 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 }
227 IRQ_ATTR_RO(wakeup);
228
name_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)229 static 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 }
242 IRQ_ATTR_RO(name);
243
actions_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)244 static 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 }
265 IRQ_ATTR_RO(actions);
266
267 static 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
278 static struct kobj_type irq_kobj_type = {
279 .release = irq_kobj_release,
280 .sysfs_ops = &kobj_sysfs_ops,
281 .default_attrs = irq_attrs,
282 };
283
irq_sysfs_add(int irq,struct irq_desc * desc)284 static 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
irq_sysfs_init(void)296 static 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 }
317 postcore_initcall(irq_sysfs_init);
318
319 #else /* !CONFIG_SYSFS */
320
321 static struct kobj_type irq_kobj_type = {
322 .release = irq_kobj_release,
323 };
324
irq_sysfs_add(int irq,struct irq_desc * desc)325 static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
326
327 #endif /* CONFIG_SYSFS */
328
329 static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
330
irq_insert_desc(unsigned int irq,struct irq_desc * desc)331 static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
332 {
333 radix_tree_insert(&irq_desc_tree, irq, desc);
334 }
335
irq_to_desc(unsigned int irq)336 struct irq_desc *irq_to_desc(unsigned int irq)
337 {
338 return radix_tree_lookup(&irq_desc_tree, irq);
339 }
340 EXPORT_SYMBOL(irq_to_desc);
341
delete_irq_desc(unsigned int irq)342 static void delete_irq_desc(unsigned int irq)
343 {
344 radix_tree_delete(&irq_desc_tree, irq);
345 }
346
347 #ifdef CONFIG_SMP
free_masks(struct irq_desc * desc)348 static 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
free_masks(struct irq_desc * desc)359 static inline void free_masks(struct irq_desc *desc) { }
360 #endif
361
irq_lock_sparse(void)362 void irq_lock_sparse(void)
363 {
364 mutex_lock(&sparse_irq_lock);
365 }
366
irq_unlock_sparse(void)367 void irq_unlock_sparse(void)
368 {
369 mutex_unlock(&sparse_irq_lock);
370 }
371
alloc_desc(int irq,int node,unsigned int flags,const struct cpumask * affinity,struct module * owner)372 static 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
400 err_kstat:
401 free_percpu(desc->kstat_irqs);
402 err_desc:
403 kfree(desc);
404 return NULL;
405 }
406
irq_kobj_release(struct kobject * kobj)407 static 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
delayed_free_desc(struct rcu_head * rhp)416 static 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
free_desc(unsigned int irq)423 static 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 * This also allows us to use rcu in kstat_irqs_usr().
447 */
448 call_rcu(&desc->rcu, delayed_free_desc);
449 }
450
alloc_descs(unsigned int start,unsigned int cnt,int node,const struct cpumask * affinity,struct module * owner)451 static int alloc_descs(unsigned int start, unsigned int cnt, int node,
452 const struct cpumask *affinity, struct module *owner)
453 {
454 const struct cpumask *mask = NULL;
455 struct irq_desc *desc;
456 unsigned int flags;
457 int i;
458
459 /* Validate affinity mask(s) */
460 if (affinity) {
461 for (i = 0, mask = affinity; i < cnt; i++, mask++) {
462 if (cpumask_empty(mask))
463 return -EINVAL;
464 }
465 }
466
467 flags = affinity ? IRQD_AFFINITY_MANAGED | IRQD_MANAGED_SHUTDOWN : 0;
468 mask = NULL;
469
470 for (i = 0; i < cnt; i++) {
471 if (affinity) {
472 node = cpu_to_node(cpumask_first(affinity));
473 mask = affinity;
474 affinity++;
475 }
476 desc = alloc_desc(start + i, node, flags, mask, owner);
477 if (!desc)
478 goto err;
479 irq_insert_desc(start + i, desc);
480 irq_sysfs_add(start + i, desc);
481 irq_add_debugfs_entry(start + i, desc);
482 }
483 bitmap_set(allocated_irqs, start, cnt);
484 return start;
485
486 err:
487 for (i--; i >= 0; i--)
488 free_desc(start + i);
489 return -ENOMEM;
490 }
491
irq_expand_nr_irqs(unsigned int nr)492 static int irq_expand_nr_irqs(unsigned int nr)
493 {
494 if (nr > IRQ_BITMAP_BITS)
495 return -ENOMEM;
496 nr_irqs = nr;
497 return 0;
498 }
499
early_irq_init(void)500 int __init early_irq_init(void)
501 {
502 int i, initcnt, node = first_online_node;
503 struct irq_desc *desc;
504
505 init_irq_default_affinity();
506
507 /* Let arch update nr_irqs and return the nr of preallocated irqs */
508 initcnt = arch_probe_nr_irqs();
509 printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
510 NR_IRQS, nr_irqs, initcnt);
511
512 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
513 nr_irqs = IRQ_BITMAP_BITS;
514
515 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
516 initcnt = IRQ_BITMAP_BITS;
517
518 if (initcnt > nr_irqs)
519 nr_irqs = initcnt;
520
521 for (i = 0; i < initcnt; i++) {
522 desc = alloc_desc(i, node, 0, NULL, NULL);
523 set_bit(i, allocated_irqs);
524 irq_insert_desc(i, desc);
525 }
526 return arch_early_irq_init();
527 }
528
529 #else /* !CONFIG_SPARSE_IRQ */
530
531 struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
532 [0 ... NR_IRQS-1] = {
533 .handle_irq = handle_bad_irq,
534 .depth = 1,
535 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
536 }
537 };
538
early_irq_init(void)539 int __init early_irq_init(void)
540 {
541 int count, i, node = first_online_node;
542 struct irq_desc *desc;
543
544 init_irq_default_affinity();
545
546 printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
547
548 desc = irq_desc;
549 count = ARRAY_SIZE(irq_desc);
550
551 for (i = 0; i < count; i++) {
552 desc[i].kstat_irqs = alloc_percpu(unsigned int);
553 alloc_masks(&desc[i], node);
554 raw_spin_lock_init(&desc[i].lock);
555 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
556 desc_set_defaults(i, &desc[i], node, NULL, NULL);
557 }
558 return arch_early_irq_init();
559 }
560
irq_to_desc(unsigned int irq)561 struct irq_desc *irq_to_desc(unsigned int irq)
562 {
563 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
564 }
565 EXPORT_SYMBOL(irq_to_desc);
566
free_desc(unsigned int irq)567 static void free_desc(unsigned int irq)
568 {
569 struct irq_desc *desc = irq_to_desc(irq);
570 unsigned long flags;
571
572 raw_spin_lock_irqsave(&desc->lock, flags);
573 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
574 raw_spin_unlock_irqrestore(&desc->lock, flags);
575 }
576
alloc_descs(unsigned int start,unsigned int cnt,int node,const struct cpumask * affinity,struct module * owner)577 static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
578 const struct cpumask *affinity,
579 struct module *owner)
580 {
581 u32 i;
582
583 for (i = 0; i < cnt; i++) {
584 struct irq_desc *desc = irq_to_desc(start + i);
585
586 desc->owner = owner;
587 }
588 bitmap_set(allocated_irqs, start, cnt);
589 return start;
590 }
591
irq_expand_nr_irqs(unsigned int nr)592 static int irq_expand_nr_irqs(unsigned int nr)
593 {
594 return -ENOMEM;
595 }
596
irq_mark_irq(unsigned int irq)597 void irq_mark_irq(unsigned int irq)
598 {
599 mutex_lock(&sparse_irq_lock);
600 bitmap_set(allocated_irqs, irq, 1);
601 mutex_unlock(&sparse_irq_lock);
602 }
603
604 #ifdef CONFIG_GENERIC_IRQ_LEGACY
irq_init_desc(unsigned int irq)605 void irq_init_desc(unsigned int irq)
606 {
607 free_desc(irq);
608 }
609 #endif
610
611 #endif /* !CONFIG_SPARSE_IRQ */
612
613 /**
614 * generic_handle_irq - Invoke the handler for a particular irq
615 * @irq: The irq number to handle
616 *
617 */
generic_handle_irq(unsigned int irq)618 int generic_handle_irq(unsigned int irq)
619 {
620 struct irq_desc *desc = irq_to_desc(irq);
621
622 if (!desc)
623 return -EINVAL;
624 generic_handle_irq_desc(desc);
625 return 0;
626 }
627 EXPORT_SYMBOL_GPL(generic_handle_irq);
628
629 #ifdef CONFIG_HANDLE_DOMAIN_IRQ
630 /**
631 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
632 * @domain: The domain where to perform the lookup
633 * @hwirq: The HW irq number to convert to a logical one
634 * @lookup: Whether to perform the domain lookup or not
635 * @regs: Register file coming from the low-level handling code
636 *
637 * Returns: 0 on success, or -EINVAL if conversion has failed
638 */
__handle_domain_irq(struct irq_domain * domain,unsigned int hwirq,bool lookup,struct pt_regs * regs)639 int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
640 bool lookup, struct pt_regs *regs)
641 {
642 struct pt_regs *old_regs = set_irq_regs(regs);
643 unsigned int irq = hwirq;
644 int ret = 0;
645
646 irq_enter();
647
648 #ifdef CONFIG_IRQ_DOMAIN
649 if (lookup)
650 irq = irq_find_mapping(domain, hwirq);
651 #endif
652
653 /*
654 * Some hardware gives randomly wrong interrupts. Rather
655 * than crashing, do something sensible.
656 */
657 if (unlikely(!irq || irq >= nr_irqs)) {
658 ack_bad_irq(irq);
659 ret = -EINVAL;
660 } else {
661 generic_handle_irq(irq);
662 }
663
664 irq_exit();
665 set_irq_regs(old_regs);
666 return ret;
667 }
668 #endif
669
670 /* Dynamic interrupt handling */
671
672 /**
673 * irq_free_descs - free irq descriptors
674 * @from: Start of descriptor range
675 * @cnt: Number of consecutive irqs to free
676 */
irq_free_descs(unsigned int from,unsigned int cnt)677 void irq_free_descs(unsigned int from, unsigned int cnt)
678 {
679 int i;
680
681 if (from >= nr_irqs || (from + cnt) > nr_irqs)
682 return;
683
684 mutex_lock(&sparse_irq_lock);
685 for (i = 0; i < cnt; i++)
686 free_desc(from + i);
687
688 bitmap_clear(allocated_irqs, from, cnt);
689 mutex_unlock(&sparse_irq_lock);
690 }
691 EXPORT_SYMBOL_GPL(irq_free_descs);
692
693 /**
694 * irq_alloc_descs - allocate and initialize a range of irq descriptors
695 * @irq: Allocate for specific irq number if irq >= 0
696 * @from: Start the search from this irq number
697 * @cnt: Number of consecutive irqs to allocate.
698 * @node: Preferred node on which the irq descriptor should be allocated
699 * @owner: Owning module (can be NULL)
700 * @affinity: Optional pointer to an affinity mask array of size @cnt which
701 * hints where the irq descriptors should be allocated and which
702 * default affinities to use
703 *
704 * Returns the first irq number or error code
705 */
706 int __ref
__irq_alloc_descs(int irq,unsigned int from,unsigned int cnt,int node,struct module * owner,const struct cpumask * affinity)707 __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
708 struct module *owner, const struct cpumask *affinity)
709 {
710 int start, ret;
711
712 if (!cnt)
713 return -EINVAL;
714
715 if (irq >= 0) {
716 if (from > irq)
717 return -EINVAL;
718 from = irq;
719 } else {
720 /*
721 * For interrupts which are freely allocated the
722 * architecture can force a lower bound to the @from
723 * argument. x86 uses this to exclude the GSI space.
724 */
725 from = arch_dynirq_lower_bound(from);
726 }
727
728 mutex_lock(&sparse_irq_lock);
729
730 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
731 from, cnt, 0);
732 ret = -EEXIST;
733 if (irq >=0 && start != irq)
734 goto unlock;
735
736 if (start + cnt > nr_irqs) {
737 ret = irq_expand_nr_irqs(start + cnt);
738 if (ret)
739 goto unlock;
740 }
741 ret = alloc_descs(start, cnt, node, affinity, owner);
742 unlock:
743 mutex_unlock(&sparse_irq_lock);
744 return ret;
745 }
746 EXPORT_SYMBOL_GPL(__irq_alloc_descs);
747
748 #ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
749 /**
750 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
751 * @cnt: number of interrupts to allocate
752 * @node: node on which to allocate
753 *
754 * Returns an interrupt number > 0 or 0, if the allocation fails.
755 */
irq_alloc_hwirqs(int cnt,int node)756 unsigned int irq_alloc_hwirqs(int cnt, int node)
757 {
758 int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL);
759
760 if (irq < 0)
761 return 0;
762
763 for (i = irq; cnt > 0; i++, cnt--) {
764 if (arch_setup_hwirq(i, node))
765 goto err;
766 irq_clear_status_flags(i, _IRQ_NOREQUEST);
767 }
768 return irq;
769
770 err:
771 for (i--; i >= irq; i--) {
772 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
773 arch_teardown_hwirq(i);
774 }
775 irq_free_descs(irq, cnt);
776 return 0;
777 }
778 EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
779
780 /**
781 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
782 * @from: Free from irq number
783 * @cnt: number of interrupts to free
784 *
785 */
irq_free_hwirqs(unsigned int from,int cnt)786 void irq_free_hwirqs(unsigned int from, int cnt)
787 {
788 int i, j;
789
790 for (i = from, j = cnt; j > 0; i++, j--) {
791 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
792 arch_teardown_hwirq(i);
793 }
794 irq_free_descs(from, cnt);
795 }
796 EXPORT_SYMBOL_GPL(irq_free_hwirqs);
797 #endif
798
799 /**
800 * irq_get_next_irq - get next allocated irq number
801 * @offset: where to start the search
802 *
803 * Returns next irq number after offset or nr_irqs if none is found.
804 */
irq_get_next_irq(unsigned int offset)805 unsigned int irq_get_next_irq(unsigned int offset)
806 {
807 return find_next_bit(allocated_irqs, nr_irqs, offset);
808 }
809
810 struct irq_desc *
__irq_get_desc_lock(unsigned int irq,unsigned long * flags,bool bus,unsigned int check)811 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
812 unsigned int check)
813 {
814 struct irq_desc *desc = irq_to_desc(irq);
815
816 if (desc) {
817 if (check & _IRQ_DESC_CHECK) {
818 if ((check & _IRQ_DESC_PERCPU) &&
819 !irq_settings_is_per_cpu_devid(desc))
820 return NULL;
821
822 if (!(check & _IRQ_DESC_PERCPU) &&
823 irq_settings_is_per_cpu_devid(desc))
824 return NULL;
825 }
826
827 if (bus)
828 chip_bus_lock(desc);
829 raw_spin_lock_irqsave(&desc->lock, *flags);
830 }
831 return desc;
832 }
833
__irq_put_desc_unlock(struct irq_desc * desc,unsigned long flags,bool bus)834 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
835 {
836 raw_spin_unlock_irqrestore(&desc->lock, flags);
837 if (bus)
838 chip_bus_sync_unlock(desc);
839 }
840
irq_set_percpu_devid_partition(unsigned int irq,const struct cpumask * affinity)841 int irq_set_percpu_devid_partition(unsigned int irq,
842 const struct cpumask *affinity)
843 {
844 struct irq_desc *desc = irq_to_desc(irq);
845
846 if (!desc)
847 return -EINVAL;
848
849 if (desc->percpu_enabled)
850 return -EINVAL;
851
852 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
853
854 if (!desc->percpu_enabled)
855 return -ENOMEM;
856
857 if (affinity)
858 desc->percpu_affinity = affinity;
859 else
860 desc->percpu_affinity = cpu_possible_mask;
861
862 irq_set_percpu_devid_flags(irq);
863 return 0;
864 }
865
irq_set_percpu_devid(unsigned int irq)866 int irq_set_percpu_devid(unsigned int irq)
867 {
868 return irq_set_percpu_devid_partition(irq, NULL);
869 }
870
irq_get_percpu_devid_partition(unsigned int irq,struct cpumask * affinity)871 int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
872 {
873 struct irq_desc *desc = irq_to_desc(irq);
874
875 if (!desc || !desc->percpu_enabled)
876 return -EINVAL;
877
878 if (affinity)
879 cpumask_copy(affinity, desc->percpu_affinity);
880
881 return 0;
882 }
883 EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
884
kstat_incr_irq_this_cpu(unsigned int irq)885 void kstat_incr_irq_this_cpu(unsigned int irq)
886 {
887 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
888 }
889
890 /**
891 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
892 * @irq: The interrupt number
893 * @cpu: The cpu number
894 *
895 * Returns the sum of interrupt counts on @cpu since boot for
896 * @irq. The caller must ensure that the interrupt is not removed
897 * concurrently.
898 */
kstat_irqs_cpu(unsigned int irq,int cpu)899 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
900 {
901 struct irq_desc *desc = irq_to_desc(irq);
902
903 return desc && desc->kstat_irqs ?
904 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
905 }
906
907 /**
908 * kstat_irqs - Get the statistics for an interrupt
909 * @irq: The interrupt number
910 *
911 * Returns the sum of interrupt counts on all cpus since boot for
912 * @irq. The caller must ensure that the interrupt is not removed
913 * concurrently.
914 */
kstat_irqs(unsigned int irq)915 unsigned int kstat_irqs(unsigned int irq)
916 {
917 struct irq_desc *desc = irq_to_desc(irq);
918 int cpu;
919 unsigned int sum = 0;
920
921 if (!desc || !desc->kstat_irqs)
922 return 0;
923 for_each_possible_cpu(cpu)
924 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
925 return sum;
926 }
927
928 /**
929 * kstat_irqs_usr - Get the statistics for an interrupt
930 * @irq: The interrupt number
931 *
932 * Returns the sum of interrupt counts on all cpus since boot for @irq.
933 * Contrary to kstat_irqs() this can be called from any context.
934 * It uses rcu since a concurrent removal of an interrupt descriptor is
935 * observing an rcu grace period before delayed_free_desc()/irq_kobj_release().
936 */
kstat_irqs_usr(unsigned int irq)937 unsigned int kstat_irqs_usr(unsigned int irq)
938 {
939 unsigned int sum;
940
941 rcu_read_lock();
942 sum = kstat_irqs(irq);
943 rcu_read_unlock();
944 return sum;
945 }
946