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1/*
2 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
3 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
4 *
5 * This file contains the interrupt descriptor management code
6 *
7 * Detailed information is available in Documentation/DocBook/genericirq
8 *
9 */
10#include <linux/irq.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/interrupt.h>
14#include <linux/kernel_stat.h>
15#include <linux/radix-tree.h>
16#include <linux/bitmap.h>
17#include <linux/irqdomain.h>
18#include <linux/sysfs.h>
19
20#include "internals.h"
21
22/*
23 * lockdep: we want to handle all irq_desc locks as a single lock-class:
24 */
25static struct lock_class_key irq_desc_lock_class;
26
27#if defined(CONFIG_SMP)
28static int __init irq_affinity_setup(char *str)
29{
30 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
31 cpulist_parse(str, irq_default_affinity);
32 /*
33 * Set at least the boot cpu. We don't want to end up with
34 * bugreports caused by random comandline masks
35 */
36 cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
37 return 1;
38}
39__setup("irqaffinity=", irq_affinity_setup);
40
41static void __init init_irq_default_affinity(void)
42{
43#ifdef CONFIG_CPUMASK_OFFSTACK
44 if (!irq_default_affinity)
45 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
46#endif
47 if (cpumask_empty(irq_default_affinity))
48 cpumask_setall(irq_default_affinity);
49}
50#else
51static void __init init_irq_default_affinity(void)
52{
53}
54#endif
55
56#ifdef CONFIG_SMP
57static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
58{
59 if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
60 gfp, node))
61 return -ENOMEM;
62
63#ifdef CONFIG_GENERIC_PENDING_IRQ
64 if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
65 free_cpumask_var(desc->irq_common_data.affinity);
66 return -ENOMEM;
67 }
68#endif
69 return 0;
70}
71
72static void desc_smp_init(struct irq_desc *desc, int node,
73 const struct cpumask *affinity)
74{
75 if (!affinity)
76 affinity = irq_default_affinity;
77 cpumask_copy(desc->irq_common_data.affinity, affinity);
78
79#ifdef CONFIG_GENERIC_PENDING_IRQ
80 cpumask_clear(desc->pending_mask);
81#endif
82#ifdef CONFIG_NUMA
83 desc->irq_common_data.node = node;
84#endif
85}
86
87#else
88static inline int
89alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
90static inline void
91desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
92#endif
93
94static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
95 const struct cpumask *affinity, struct module *owner)
96{
97 int cpu;
98
99 desc->irq_common_data.handler_data = NULL;
100 desc->irq_common_data.msi_desc = NULL;
101
102 desc->irq_data.common = &desc->irq_common_data;
103 desc->irq_data.irq = irq;
104 desc->irq_data.chip = &no_irq_chip;
105 desc->irq_data.chip_data = NULL;
106 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
107 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
108 desc->handle_irq = handle_bad_irq;
109 desc->depth = 1;
110 desc->irq_count = 0;
111 desc->irqs_unhandled = 0;
112 desc->name = NULL;
113 desc->owner = owner;
114 for_each_possible_cpu(cpu)
115 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
116 desc_smp_init(desc, node, affinity);
117}
118
119int nr_irqs = NR_IRQS;
120EXPORT_SYMBOL_GPL(nr_irqs);
121
122static DEFINE_MUTEX(sparse_irq_lock);
123static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
124
125#ifdef CONFIG_SPARSE_IRQ
126
127static void irq_kobj_release(struct kobject *kobj);
128
129#ifdef CONFIG_SYSFS
130static struct kobject *irq_kobj_base;
131
132#define IRQ_ATTR_RO(_name) \
133static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
134
135static ssize_t per_cpu_count_show(struct kobject *kobj,
136 struct kobj_attribute *attr, char *buf)
137{
138 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
139 int cpu, irq = desc->irq_data.irq;
140 ssize_t ret = 0;
141 char *p = "";
142
143 for_each_possible_cpu(cpu) {
144 unsigned int c = kstat_irqs_cpu(irq, cpu);
145
146 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
147 p = ",";
148 }
149
150 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
151 return ret;
152}
153IRQ_ATTR_RO(per_cpu_count);
154
155static ssize_t chip_name_show(struct kobject *kobj,
156 struct kobj_attribute *attr, char *buf)
157{
158 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
159 ssize_t ret = 0;
160
161 raw_spin_lock_irq(&desc->lock);
162 if (desc->irq_data.chip && desc->irq_data.chip->name) {
163 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
164 desc->irq_data.chip->name);
165 }
166 raw_spin_unlock_irq(&desc->lock);
167
168 return ret;
169}
170IRQ_ATTR_RO(chip_name);
171
172static ssize_t hwirq_show(struct kobject *kobj,
173 struct kobj_attribute *attr, char *buf)
174{
175 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
176 ssize_t ret = 0;
177
178 raw_spin_lock_irq(&desc->lock);
179 if (desc->irq_data.domain)
180 ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq);
181 raw_spin_unlock_irq(&desc->lock);
182
183 return ret;
184}
185IRQ_ATTR_RO(hwirq);
186
187static ssize_t type_show(struct kobject *kobj,
188 struct kobj_attribute *attr, char *buf)
189{
190 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
191 ssize_t ret = 0;
192
193 raw_spin_lock_irq(&desc->lock);
194 ret = sprintf(buf, "%s\n",
195 irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
196 raw_spin_unlock_irq(&desc->lock);
197
198 return ret;
199
200}
201IRQ_ATTR_RO(type);
202
203static ssize_t name_show(struct kobject *kobj,
204 struct kobj_attribute *attr, char *buf)
205{
206 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
207 ssize_t ret = 0;
208
209 raw_spin_lock_irq(&desc->lock);
210 if (desc->name)
211 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
212 raw_spin_unlock_irq(&desc->lock);
213
214 return ret;
215}
216IRQ_ATTR_RO(name);
217
218static ssize_t actions_show(struct kobject *kobj,
219 struct kobj_attribute *attr, char *buf)
220{
221 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
222 struct irqaction *action;
223 ssize_t ret = 0;
224 char *p = "";
225
226 raw_spin_lock_irq(&desc->lock);
227 for (action = desc->action; action != NULL; action = action->next) {
228 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
229 p, action->name);
230 p = ",";
231 }
232 raw_spin_unlock_irq(&desc->lock);
233
234 if (ret)
235 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
236
237 return ret;
238}
239IRQ_ATTR_RO(actions);
240
241static struct attribute *irq_attrs[] = {
242 &per_cpu_count_attr.attr,
243 &chip_name_attr.attr,
244 &hwirq_attr.attr,
245 &type_attr.attr,
246 &name_attr.attr,
247 &actions_attr.attr,
248 NULL
249};
250
251static struct kobj_type irq_kobj_type = {
252 .release = irq_kobj_release,
253 .sysfs_ops = &kobj_sysfs_ops,
254 .default_attrs = irq_attrs,
255};
256
257static void irq_sysfs_add(int irq, struct irq_desc *desc)
258{
259 if (irq_kobj_base) {
260 /*
261 * Continue even in case of failure as this is nothing
262 * crucial.
263 */
264 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
265 pr_warn("Failed to add kobject for irq %d\n", irq);
266 }
267}
268
269static int __init irq_sysfs_init(void)
270{
271 struct irq_desc *desc;
272 int irq;
273
274 /* Prevent concurrent irq alloc/free */
275 irq_lock_sparse();
276
277 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
278 if (!irq_kobj_base) {
279 irq_unlock_sparse();
280 return -ENOMEM;
281 }
282
283 /* Add the already allocated interrupts */
284 for_each_irq_desc(irq, desc)
285 irq_sysfs_add(irq, desc);
286 irq_unlock_sparse();
287
288 return 0;
289}
290postcore_initcall(irq_sysfs_init);
291
292#else /* !CONFIG_SYSFS */
293
294static struct kobj_type irq_kobj_type = {
295 .release = irq_kobj_release,
296};
297
298static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
299
300#endif /* CONFIG_SYSFS */
301
302static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
303
304static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
305{
306 radix_tree_insert(&irq_desc_tree, irq, desc);
307}
308
309struct irq_desc *irq_to_desc(unsigned int irq)
310{
311 return radix_tree_lookup(&irq_desc_tree, irq);
312}
313EXPORT_SYMBOL(irq_to_desc);
314
315static void delete_irq_desc(unsigned int irq)
316{
317 radix_tree_delete(&irq_desc_tree, irq);
318}
319
320#ifdef CONFIG_SMP
321static void free_masks(struct irq_desc *desc)
322{
323#ifdef CONFIG_GENERIC_PENDING_IRQ
324 free_cpumask_var(desc->pending_mask);
325#endif
326 free_cpumask_var(desc->irq_common_data.affinity);
327}
328#else
329static inline void free_masks(struct irq_desc *desc) { }
330#endif
331
332void irq_lock_sparse(void)
333{
334 mutex_lock(&sparse_irq_lock);
335}
336
337void irq_unlock_sparse(void)
338{
339 mutex_unlock(&sparse_irq_lock);
340}
341
342static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
343 const struct cpumask *affinity,
344 struct module *owner)
345{
346 struct irq_desc *desc;
347 gfp_t gfp = GFP_KERNEL;
348
349 desc = kzalloc_node(sizeof(*desc), gfp, node);
350 if (!desc)
351 return NULL;
352 /* allocate based on nr_cpu_ids */
353 desc->kstat_irqs = alloc_percpu(unsigned int);
354 if (!desc->kstat_irqs)
355 goto err_desc;
356
357 if (alloc_masks(desc, gfp, node))
358 goto err_kstat;
359
360 raw_spin_lock_init(&desc->lock);
361 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
362 init_rcu_head(&desc->rcu);
363
364 desc_set_defaults(irq, desc, node, affinity, owner);
365 irqd_set(&desc->irq_data, flags);
366 kobject_init(&desc->kobj, &irq_kobj_type);
367
368 return desc;
369
370err_kstat:
371 free_percpu(desc->kstat_irqs);
372err_desc:
373 kfree(desc);
374 return NULL;
375}
376
377static void irq_kobj_release(struct kobject *kobj)
378{
379 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
380
381 free_masks(desc);
382 free_percpu(desc->kstat_irqs);
383 kfree(desc);
384}
385
386static void delayed_free_desc(struct rcu_head *rhp)
387{
388 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
389
390 kobject_put(&desc->kobj);
391}
392
393static void free_desc(unsigned int irq)
394{
395 struct irq_desc *desc = irq_to_desc(irq);
396
397 unregister_irq_proc(irq, desc);
398
399 /*
400 * sparse_irq_lock protects also show_interrupts() and
401 * kstat_irq_usr(). Once we deleted the descriptor from the
402 * sparse tree we can free it. Access in proc will fail to
403 * lookup the descriptor.
404 *
405 * The sysfs entry must be serialized against a concurrent
406 * irq_sysfs_init() as well.
407 */
408 mutex_lock(&sparse_irq_lock);
409 kobject_del(&desc->kobj);
410 delete_irq_desc(irq);
411 mutex_unlock(&sparse_irq_lock);
412
413 /*
414 * We free the descriptor, masks and stat fields via RCU. That
415 * allows demultiplex interrupts to do rcu based management of
416 * the child interrupts.
417 */
418 call_rcu(&desc->rcu, delayed_free_desc);
419}
420
421static int alloc_descs(unsigned int start, unsigned int cnt, int node,
422 const struct cpumask *affinity, struct module *owner)
423{
424 const struct cpumask *mask = NULL;
425 struct irq_desc *desc;
426 unsigned int flags;
427 int i;
428
429 /* Validate affinity mask(s) */
430 if (affinity) {
431 for (i = 0, mask = affinity; i < cnt; i++, mask++) {
432 if (cpumask_empty(mask))
433 return -EINVAL;
434 }
435 }
436
437 flags = affinity ? IRQD_AFFINITY_MANAGED : 0;
438 mask = NULL;
439
440 for (i = 0; i < cnt; i++) {
441 if (affinity) {
442 node = cpu_to_node(cpumask_first(affinity));
443 mask = affinity;
444 affinity++;
445 }
446 desc = alloc_desc(start + i, node, flags, mask, owner);
447 if (!desc)
448 goto err;
449 mutex_lock(&sparse_irq_lock);
450 irq_insert_desc(start + i, desc);
451 irq_sysfs_add(start + i, desc);
452 mutex_unlock(&sparse_irq_lock);
453 }
454 return start;
455
456err:
457 for (i--; i >= 0; i--)
458 free_desc(start + i);
459
460 mutex_lock(&sparse_irq_lock);
461 bitmap_clear(allocated_irqs, start, cnt);
462 mutex_unlock(&sparse_irq_lock);
463 return -ENOMEM;
464}
465
466static int irq_expand_nr_irqs(unsigned int nr)
467{
468 if (nr > IRQ_BITMAP_BITS)
469 return -ENOMEM;
470 nr_irqs = nr;
471 return 0;
472}
473
474int __init early_irq_init(void)
475{
476 int i, initcnt, node = first_online_node;
477 struct irq_desc *desc;
478
479 init_irq_default_affinity();
480
481 /* Let arch update nr_irqs and return the nr of preallocated irqs */
482 initcnt = arch_probe_nr_irqs();
483 printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
484
485 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
486 nr_irqs = IRQ_BITMAP_BITS;
487
488 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
489 initcnt = IRQ_BITMAP_BITS;
490
491 if (initcnt > nr_irqs)
492 nr_irqs = initcnt;
493
494 for (i = 0; i < initcnt; i++) {
495 desc = alloc_desc(i, node, 0, NULL, NULL);
496 set_bit(i, allocated_irqs);
497 irq_insert_desc(i, desc);
498 }
499 return arch_early_irq_init();
500}
501
502#else /* !CONFIG_SPARSE_IRQ */
503
504struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
505 [0 ... NR_IRQS-1] = {
506 .handle_irq = handle_bad_irq,
507 .depth = 1,
508 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
509 }
510};
511
512int __init early_irq_init(void)
513{
514 int count, i, node = first_online_node;
515 struct irq_desc *desc;
516
517 init_irq_default_affinity();
518
519 printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
520
521 desc = irq_desc;
522 count = ARRAY_SIZE(irq_desc);
523
524 for (i = 0; i < count; i++) {
525 desc[i].kstat_irqs = alloc_percpu(unsigned int);
526 alloc_masks(&desc[i], GFP_KERNEL, node);
527 raw_spin_lock_init(&desc[i].lock);
528 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
529 desc_set_defaults(i, &desc[i], node, NULL, NULL);
530 }
531 return arch_early_irq_init();
532}
533
534struct irq_desc *irq_to_desc(unsigned int irq)
535{
536 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
537}
538EXPORT_SYMBOL(irq_to_desc);
539
540static void free_desc(unsigned int irq)
541{
542 struct irq_desc *desc = irq_to_desc(irq);
543 unsigned long flags;
544
545 raw_spin_lock_irqsave(&desc->lock, flags);
546 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
547 raw_spin_unlock_irqrestore(&desc->lock, flags);
548}
549
550static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
551 const struct cpumask *affinity,
552 struct module *owner)
553{
554 u32 i;
555
556 for (i = 0; i < cnt; i++) {
557 struct irq_desc *desc = irq_to_desc(start + i);
558
559 desc->owner = owner;
560 }
561 return start;
562}
563
564static int irq_expand_nr_irqs(unsigned int nr)
565{
566 return -ENOMEM;
567}
568
569void irq_mark_irq(unsigned int irq)
570{
571 mutex_lock(&sparse_irq_lock);
572 bitmap_set(allocated_irqs, irq, 1);
573 mutex_unlock(&sparse_irq_lock);
574}
575
576#ifdef CONFIG_GENERIC_IRQ_LEGACY
577void irq_init_desc(unsigned int irq)
578{
579 free_desc(irq);
580}
581#endif
582
583#endif /* !CONFIG_SPARSE_IRQ */
584
585/**
586 * generic_handle_irq - Invoke the handler for a particular irq
587 * @irq: The irq number to handle
588 *
589 */
590int generic_handle_irq(unsigned int irq)
591{
592 struct irq_desc *desc = irq_to_desc(irq);
593
594 if (!desc)
595 return -EINVAL;
596 generic_handle_irq_desc(desc);
597 return 0;
598}
599EXPORT_SYMBOL_GPL(generic_handle_irq);
600
601#ifdef CONFIG_HANDLE_DOMAIN_IRQ
602/**
603 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
604 * @domain: The domain where to perform the lookup
605 * @hwirq: The HW irq number to convert to a logical one
606 * @lookup: Whether to perform the domain lookup or not
607 * @regs: Register file coming from the low-level handling code
608 *
609 * Returns: 0 on success, or -EINVAL if conversion has failed
610 */
611int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
612 bool lookup, struct pt_regs *regs)
613{
614 struct pt_regs *old_regs = set_irq_regs(regs);
615 unsigned int irq = hwirq;
616 int ret = 0;
617
618 irq_enter();
619
620#ifdef CONFIG_IRQ_DOMAIN
621 if (lookup)
622 irq = irq_find_mapping(domain, hwirq);
623#endif
624
625 /*
626 * Some hardware gives randomly wrong interrupts. Rather
627 * than crashing, do something sensible.
628 */
629 if (unlikely(!irq || irq >= nr_irqs)) {
630 ack_bad_irq(irq);
631 ret = -EINVAL;
632 } else {
633 generic_handle_irq(irq);
634 }
635
636 irq_exit();
637 set_irq_regs(old_regs);
638 return ret;
639}
640#endif
641
642/* Dynamic interrupt handling */
643
644/**
645 * irq_free_descs - free irq descriptors
646 * @from: Start of descriptor range
647 * @cnt: Number of consecutive irqs to free
648 */
649void irq_free_descs(unsigned int from, unsigned int cnt)
650{
651 int i;
652
653 if (from >= nr_irqs || (from + cnt) > nr_irqs)
654 return;
655
656 for (i = 0; i < cnt; i++)
657 free_desc(from + i);
658
659 mutex_lock(&sparse_irq_lock);
660 bitmap_clear(allocated_irqs, from, cnt);
661 mutex_unlock(&sparse_irq_lock);
662}
663EXPORT_SYMBOL_GPL(irq_free_descs);
664
665/**
666 * irq_alloc_descs - allocate and initialize a range of irq descriptors
667 * @irq: Allocate for specific irq number if irq >= 0
668 * @from: Start the search from this irq number
669 * @cnt: Number of consecutive irqs to allocate.
670 * @node: Preferred node on which the irq descriptor should be allocated
671 * @owner: Owning module (can be NULL)
672 * @affinity: Optional pointer to an affinity mask array of size @cnt which
673 * hints where the irq descriptors should be allocated and which
674 * default affinities to use
675 *
676 * Returns the first irq number or error code
677 */
678int __ref
679__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
680 struct module *owner, const struct cpumask *affinity)
681{
682 int start, ret;
683
684 if (!cnt)
685 return -EINVAL;
686
687 if (irq >= 0) {
688 if (from > irq)
689 return -EINVAL;
690 from = irq;
691 } else {
692 /*
693 * For interrupts which are freely allocated the
694 * architecture can force a lower bound to the @from
695 * argument. x86 uses this to exclude the GSI space.
696 */
697 from = arch_dynirq_lower_bound(from);
698 }
699
700 mutex_lock(&sparse_irq_lock);
701
702 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
703 from, cnt, 0);
704 ret = -EEXIST;
705 if (irq >=0 && start != irq)
706 goto err;
707
708 if (start + cnt > nr_irqs) {
709 ret = irq_expand_nr_irqs(start + cnt);
710 if (ret)
711 goto err;
712 }
713
714 bitmap_set(allocated_irqs, start, cnt);
715 mutex_unlock(&sparse_irq_lock);
716 return alloc_descs(start, cnt, node, affinity, owner);
717
718err:
719 mutex_unlock(&sparse_irq_lock);
720 return ret;
721}
722EXPORT_SYMBOL_GPL(__irq_alloc_descs);
723
724#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
725/**
726 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
727 * @cnt: number of interrupts to allocate
728 * @node: node on which to allocate
729 *
730 * Returns an interrupt number > 0 or 0, if the allocation fails.
731 */
732unsigned int irq_alloc_hwirqs(int cnt, int node)
733{
734 int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL);
735
736 if (irq < 0)
737 return 0;
738
739 for (i = irq; cnt > 0; i++, cnt--) {
740 if (arch_setup_hwirq(i, node))
741 goto err;
742 irq_clear_status_flags(i, _IRQ_NOREQUEST);
743 }
744 return irq;
745
746err:
747 for (i--; i >= irq; i--) {
748 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
749 arch_teardown_hwirq(i);
750 }
751 irq_free_descs(irq, cnt);
752 return 0;
753}
754EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
755
756/**
757 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
758 * @from: Free from irq number
759 * @cnt: number of interrupts to free
760 *
761 */
762void irq_free_hwirqs(unsigned int from, int cnt)
763{
764 int i, j;
765
766 for (i = from, j = cnt; j > 0; i++, j--) {
767 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
768 arch_teardown_hwirq(i);
769 }
770 irq_free_descs(from, cnt);
771}
772EXPORT_SYMBOL_GPL(irq_free_hwirqs);
773#endif
774
775/**
776 * irq_get_next_irq - get next allocated irq number
777 * @offset: where to start the search
778 *
779 * Returns next irq number after offset or nr_irqs if none is found.
780 */
781unsigned int irq_get_next_irq(unsigned int offset)
782{
783 return find_next_bit(allocated_irqs, nr_irqs, offset);
784}
785
786struct irq_desc *
787__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
788 unsigned int check)
789{
790 struct irq_desc *desc = irq_to_desc(irq);
791
792 if (desc) {
793 if (check & _IRQ_DESC_CHECK) {
794 if ((check & _IRQ_DESC_PERCPU) &&
795 !irq_settings_is_per_cpu_devid(desc))
796 return NULL;
797
798 if (!(check & _IRQ_DESC_PERCPU) &&
799 irq_settings_is_per_cpu_devid(desc))
800 return NULL;
801 }
802
803 if (bus)
804 chip_bus_lock(desc);
805 raw_spin_lock_irqsave(&desc->lock, *flags);
806 }
807 return desc;
808}
809
810void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
811{
812 raw_spin_unlock_irqrestore(&desc->lock, flags);
813 if (bus)
814 chip_bus_sync_unlock(desc);
815}
816
817int irq_set_percpu_devid_partition(unsigned int irq,
818 const struct cpumask *affinity)
819{
820 struct irq_desc *desc = irq_to_desc(irq);
821
822 if (!desc)
823 return -EINVAL;
824
825 if (desc->percpu_enabled)
826 return -EINVAL;
827
828 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
829
830 if (!desc->percpu_enabled)
831 return -ENOMEM;
832
833 if (affinity)
834 desc->percpu_affinity = affinity;
835 else
836 desc->percpu_affinity = cpu_possible_mask;
837
838 irq_set_percpu_devid_flags(irq);
839 return 0;
840}
841
842int irq_set_percpu_devid(unsigned int irq)
843{
844 return irq_set_percpu_devid_partition(irq, NULL);
845}
846
847int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
848{
849 struct irq_desc *desc = irq_to_desc(irq);
850
851 if (!desc || !desc->percpu_enabled)
852 return -EINVAL;
853
854 if (affinity)
855 cpumask_copy(affinity, desc->percpu_affinity);
856
857 return 0;
858}
859
860void kstat_incr_irq_this_cpu(unsigned int irq)
861{
862 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
863}
864
865/**
866 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
867 * @irq: The interrupt number
868 * @cpu: The cpu number
869 *
870 * Returns the sum of interrupt counts on @cpu since boot for
871 * @irq. The caller must ensure that the interrupt is not removed
872 * concurrently.
873 */
874unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
875{
876 struct irq_desc *desc = irq_to_desc(irq);
877
878 return desc && desc->kstat_irqs ?
879 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
880}
881
882/**
883 * kstat_irqs - Get the statistics for an interrupt
884 * @irq: The interrupt number
885 *
886 * Returns the sum of interrupt counts on all cpus since boot for
887 * @irq. The caller must ensure that the interrupt is not removed
888 * concurrently.
889 */
890unsigned int kstat_irqs(unsigned int irq)
891{
892 struct irq_desc *desc = irq_to_desc(irq);
893 int cpu;
894 unsigned int sum = 0;
895
896 if (!desc || !desc->kstat_irqs)
897 return 0;
898 for_each_possible_cpu(cpu)
899 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
900 return sum;
901}
902
903/**
904 * kstat_irqs_usr - Get the statistics for an interrupt
905 * @irq: The interrupt number
906 *
907 * Returns the sum of interrupt counts on all cpus since boot for
908 * @irq. Contrary to kstat_irqs() this can be called from any
909 * preemptible context. It's protected against concurrent removal of
910 * an interrupt descriptor when sparse irqs are enabled.
911 */
912unsigned int kstat_irqs_usr(unsigned int irq)
913{
914 unsigned int sum;
915
916 irq_lock_sparse();
917 sum = kstat_irqs(irq);
918 irq_unlock_sparse();
919 return sum;
920}
1/*
2 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
3 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
4 *
5 * This file contains the interrupt descriptor management code
6 *
7 * Detailed information is available in Documentation/DocBook/genericirq
8 *
9 */
10#include <linux/irq.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/interrupt.h>
14#include <linux/kernel_stat.h>
15#include <linux/radix-tree.h>
16#include <linux/bitmap.h>
17
18#include "internals.h"
19
20/*
21 * lockdep: we want to handle all irq_desc locks as a single lock-class:
22 */
23static struct lock_class_key irq_desc_lock_class;
24
25#if defined(CONFIG_SMP)
26static void __init init_irq_default_affinity(void)
27{
28 alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
29 cpumask_setall(irq_default_affinity);
30}
31#else
32static void __init init_irq_default_affinity(void)
33{
34}
35#endif
36
37#ifdef CONFIG_SMP
38static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
39{
40 if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node))
41 return -ENOMEM;
42
43#ifdef CONFIG_GENERIC_PENDING_IRQ
44 if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
45 free_cpumask_var(desc->irq_data.affinity);
46 return -ENOMEM;
47 }
48#endif
49 return 0;
50}
51
52static void desc_smp_init(struct irq_desc *desc, int node)
53{
54 desc->irq_data.node = node;
55 cpumask_copy(desc->irq_data.affinity, irq_default_affinity);
56#ifdef CONFIG_GENERIC_PENDING_IRQ
57 cpumask_clear(desc->pending_mask);
58#endif
59}
60
61static inline int desc_node(struct irq_desc *desc)
62{
63 return desc->irq_data.node;
64}
65
66#else
67static inline int
68alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
69static inline void desc_smp_init(struct irq_desc *desc, int node) { }
70static inline int desc_node(struct irq_desc *desc) { return 0; }
71#endif
72
73static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
74 struct module *owner)
75{
76 int cpu;
77
78 desc->irq_data.irq = irq;
79 desc->irq_data.chip = &no_irq_chip;
80 desc->irq_data.chip_data = NULL;
81 desc->irq_data.handler_data = NULL;
82 desc->irq_data.msi_desc = NULL;
83 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
84 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
85 desc->handle_irq = handle_bad_irq;
86 desc->depth = 1;
87 desc->irq_count = 0;
88 desc->irqs_unhandled = 0;
89 desc->name = NULL;
90 desc->owner = owner;
91 for_each_possible_cpu(cpu)
92 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
93 desc_smp_init(desc, node);
94}
95
96int nr_irqs = NR_IRQS;
97EXPORT_SYMBOL_GPL(nr_irqs);
98
99static DEFINE_MUTEX(sparse_irq_lock);
100static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
101
102#ifdef CONFIG_SPARSE_IRQ
103
104static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
105
106static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
107{
108 radix_tree_insert(&irq_desc_tree, irq, desc);
109}
110
111struct irq_desc *irq_to_desc(unsigned int irq)
112{
113 return radix_tree_lookup(&irq_desc_tree, irq);
114}
115EXPORT_SYMBOL(irq_to_desc);
116
117static void delete_irq_desc(unsigned int irq)
118{
119 radix_tree_delete(&irq_desc_tree, irq);
120}
121
122#ifdef CONFIG_SMP
123static void free_masks(struct irq_desc *desc)
124{
125#ifdef CONFIG_GENERIC_PENDING_IRQ
126 free_cpumask_var(desc->pending_mask);
127#endif
128 free_cpumask_var(desc->irq_data.affinity);
129}
130#else
131static inline void free_masks(struct irq_desc *desc) { }
132#endif
133
134static struct irq_desc *alloc_desc(int irq, int node, struct module *owner)
135{
136 struct irq_desc *desc;
137 gfp_t gfp = GFP_KERNEL;
138
139 desc = kzalloc_node(sizeof(*desc), gfp, node);
140 if (!desc)
141 return NULL;
142 /* allocate based on nr_cpu_ids */
143 desc->kstat_irqs = alloc_percpu(unsigned int);
144 if (!desc->kstat_irqs)
145 goto err_desc;
146
147 if (alloc_masks(desc, gfp, node))
148 goto err_kstat;
149
150 raw_spin_lock_init(&desc->lock);
151 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
152
153 desc_set_defaults(irq, desc, node, owner);
154
155 return desc;
156
157err_kstat:
158 free_percpu(desc->kstat_irqs);
159err_desc:
160 kfree(desc);
161 return NULL;
162}
163
164static void free_desc(unsigned int irq)
165{
166 struct irq_desc *desc = irq_to_desc(irq);
167
168 unregister_irq_proc(irq, desc);
169
170 mutex_lock(&sparse_irq_lock);
171 delete_irq_desc(irq);
172 mutex_unlock(&sparse_irq_lock);
173
174 free_masks(desc);
175 free_percpu(desc->kstat_irqs);
176 kfree(desc);
177}
178
179static int alloc_descs(unsigned int start, unsigned int cnt, int node,
180 struct module *owner)
181{
182 struct irq_desc *desc;
183 int i;
184
185 for (i = 0; i < cnt; i++) {
186 desc = alloc_desc(start + i, node, owner);
187 if (!desc)
188 goto err;
189 mutex_lock(&sparse_irq_lock);
190 irq_insert_desc(start + i, desc);
191 mutex_unlock(&sparse_irq_lock);
192 }
193 return start;
194
195err:
196 for (i--; i >= 0; i--)
197 free_desc(start + i);
198
199 mutex_lock(&sparse_irq_lock);
200 bitmap_clear(allocated_irqs, start, cnt);
201 mutex_unlock(&sparse_irq_lock);
202 return -ENOMEM;
203}
204
205static int irq_expand_nr_irqs(unsigned int nr)
206{
207 if (nr > IRQ_BITMAP_BITS)
208 return -ENOMEM;
209 nr_irqs = nr;
210 return 0;
211}
212
213int __init early_irq_init(void)
214{
215 int i, initcnt, node = first_online_node;
216 struct irq_desc *desc;
217
218 init_irq_default_affinity();
219
220 /* Let arch update nr_irqs and return the nr of preallocated irqs */
221 initcnt = arch_probe_nr_irqs();
222 printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
223
224 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
225 nr_irqs = IRQ_BITMAP_BITS;
226
227 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
228 initcnt = IRQ_BITMAP_BITS;
229
230 if (initcnt > nr_irqs)
231 nr_irqs = initcnt;
232
233 for (i = 0; i < initcnt; i++) {
234 desc = alloc_desc(i, node, NULL);
235 set_bit(i, allocated_irqs);
236 irq_insert_desc(i, desc);
237 }
238 return arch_early_irq_init();
239}
240
241#else /* !CONFIG_SPARSE_IRQ */
242
243struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
244 [0 ... NR_IRQS-1] = {
245 .handle_irq = handle_bad_irq,
246 .depth = 1,
247 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
248 }
249};
250
251int __init early_irq_init(void)
252{
253 int count, i, node = first_online_node;
254 struct irq_desc *desc;
255
256 init_irq_default_affinity();
257
258 printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
259
260 desc = irq_desc;
261 count = ARRAY_SIZE(irq_desc);
262
263 for (i = 0; i < count; i++) {
264 desc[i].kstat_irqs = alloc_percpu(unsigned int);
265 alloc_masks(&desc[i], GFP_KERNEL, node);
266 raw_spin_lock_init(&desc[i].lock);
267 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
268 desc_set_defaults(i, &desc[i], node, NULL);
269 }
270 return arch_early_irq_init();
271}
272
273struct irq_desc *irq_to_desc(unsigned int irq)
274{
275 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
276}
277EXPORT_SYMBOL(irq_to_desc);
278
279static void free_desc(unsigned int irq)
280{
281 dynamic_irq_cleanup(irq);
282}
283
284static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
285 struct module *owner)
286{
287 u32 i;
288
289 for (i = 0; i < cnt; i++) {
290 struct irq_desc *desc = irq_to_desc(start + i);
291
292 desc->owner = owner;
293 }
294 return start;
295}
296
297static int irq_expand_nr_irqs(unsigned int nr)
298{
299 return -ENOMEM;
300}
301
302#endif /* !CONFIG_SPARSE_IRQ */
303
304/**
305 * generic_handle_irq - Invoke the handler for a particular irq
306 * @irq: The irq number to handle
307 *
308 */
309int generic_handle_irq(unsigned int irq)
310{
311 struct irq_desc *desc = irq_to_desc(irq);
312
313 if (!desc)
314 return -EINVAL;
315 generic_handle_irq_desc(irq, desc);
316 return 0;
317}
318EXPORT_SYMBOL_GPL(generic_handle_irq);
319
320/* Dynamic interrupt handling */
321
322/**
323 * irq_free_descs - free irq descriptors
324 * @from: Start of descriptor range
325 * @cnt: Number of consecutive irqs to free
326 */
327void irq_free_descs(unsigned int from, unsigned int cnt)
328{
329 int i;
330
331 if (from >= nr_irqs || (from + cnt) > nr_irqs)
332 return;
333
334 for (i = 0; i < cnt; i++)
335 free_desc(from + i);
336
337 mutex_lock(&sparse_irq_lock);
338 bitmap_clear(allocated_irqs, from, cnt);
339 mutex_unlock(&sparse_irq_lock);
340}
341EXPORT_SYMBOL_GPL(irq_free_descs);
342
343/**
344 * irq_alloc_descs - allocate and initialize a range of irq descriptors
345 * @irq: Allocate for specific irq number if irq >= 0
346 * @from: Start the search from this irq number
347 * @cnt: Number of consecutive irqs to allocate.
348 * @node: Preferred node on which the irq descriptor should be allocated
349 * @owner: Owning module (can be NULL)
350 *
351 * Returns the first irq number or error code
352 */
353int __ref
354__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
355 struct module *owner)
356{
357 int start, ret;
358
359 if (!cnt)
360 return -EINVAL;
361
362 if (irq >= 0) {
363 if (from > irq)
364 return -EINVAL;
365 from = irq;
366 } else {
367 /*
368 * For interrupts which are freely allocated the
369 * architecture can force a lower bound to the @from
370 * argument. x86 uses this to exclude the GSI space.
371 */
372 from = arch_dynirq_lower_bound(from);
373 }
374
375 mutex_lock(&sparse_irq_lock);
376
377 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
378 from, cnt, 0);
379 ret = -EEXIST;
380 if (irq >=0 && start != irq)
381 goto err;
382
383 if (start + cnt > nr_irqs) {
384 ret = irq_expand_nr_irqs(start + cnt);
385 if (ret)
386 goto err;
387 }
388
389 bitmap_set(allocated_irqs, start, cnt);
390 mutex_unlock(&sparse_irq_lock);
391 return alloc_descs(start, cnt, node, owner);
392
393err:
394 mutex_unlock(&sparse_irq_lock);
395 return ret;
396}
397EXPORT_SYMBOL_GPL(__irq_alloc_descs);
398
399/**
400 * irq_reserve_irqs - mark irqs allocated
401 * @from: mark from irq number
402 * @cnt: number of irqs to mark
403 *
404 * Returns 0 on success or an appropriate error code
405 */
406int irq_reserve_irqs(unsigned int from, unsigned int cnt)
407{
408 unsigned int start;
409 int ret = 0;
410
411 if (!cnt || (from + cnt) > nr_irqs)
412 return -EINVAL;
413
414 mutex_lock(&sparse_irq_lock);
415 start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
416 if (start == from)
417 bitmap_set(allocated_irqs, start, cnt);
418 else
419 ret = -EEXIST;
420 mutex_unlock(&sparse_irq_lock);
421 return ret;
422}
423
424/**
425 * irq_get_next_irq - get next allocated irq number
426 * @offset: where to start the search
427 *
428 * Returns next irq number after offset or nr_irqs if none is found.
429 */
430unsigned int irq_get_next_irq(unsigned int offset)
431{
432 return find_next_bit(allocated_irqs, nr_irqs, offset);
433}
434
435struct irq_desc *
436__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
437 unsigned int check)
438{
439 struct irq_desc *desc = irq_to_desc(irq);
440
441 if (desc) {
442 if (check & _IRQ_DESC_CHECK) {
443 if ((check & _IRQ_DESC_PERCPU) &&
444 !irq_settings_is_per_cpu_devid(desc))
445 return NULL;
446
447 if (!(check & _IRQ_DESC_PERCPU) &&
448 irq_settings_is_per_cpu_devid(desc))
449 return NULL;
450 }
451
452 if (bus)
453 chip_bus_lock(desc);
454 raw_spin_lock_irqsave(&desc->lock, *flags);
455 }
456 return desc;
457}
458
459void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
460{
461 raw_spin_unlock_irqrestore(&desc->lock, flags);
462 if (bus)
463 chip_bus_sync_unlock(desc);
464}
465
466int irq_set_percpu_devid(unsigned int irq)
467{
468 struct irq_desc *desc = irq_to_desc(irq);
469
470 if (!desc)
471 return -EINVAL;
472
473 if (desc->percpu_enabled)
474 return -EINVAL;
475
476 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
477
478 if (!desc->percpu_enabled)
479 return -ENOMEM;
480
481 irq_set_percpu_devid_flags(irq);
482 return 0;
483}
484
485/**
486 * dynamic_irq_cleanup - cleanup a dynamically allocated irq
487 * @irq: irq number to initialize
488 */
489void dynamic_irq_cleanup(unsigned int irq)
490{
491 struct irq_desc *desc = irq_to_desc(irq);
492 unsigned long flags;
493
494 raw_spin_lock_irqsave(&desc->lock, flags);
495 desc_set_defaults(irq, desc, desc_node(desc), NULL);
496 raw_spin_unlock_irqrestore(&desc->lock, flags);
497}
498
499void kstat_incr_irq_this_cpu(unsigned int irq)
500{
501 kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
502}
503
504unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
505{
506 struct irq_desc *desc = irq_to_desc(irq);
507
508 return desc && desc->kstat_irqs ?
509 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
510}
511
512unsigned int kstat_irqs(unsigned int irq)
513{
514 struct irq_desc *desc = irq_to_desc(irq);
515 int cpu;
516 int sum = 0;
517
518 if (!desc || !desc->kstat_irqs)
519 return 0;
520 for_each_possible_cpu(cpu)
521 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
522 return sum;
523}