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v4.6
 
  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
 19#include "internals.h"
 20
 21/*
 22 * lockdep: we want to handle all irq_desc locks as a single lock-class:
 23 */
 24static struct lock_class_key irq_desc_lock_class;
 25
 26#if defined(CONFIG_SMP)
 27static int __init irq_affinity_setup(char *str)
 28{
 29	zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
 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 comandline masks
 34	 */
 35	cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
 36	return 1;
 37}
 38__setup("irqaffinity=", irq_affinity_setup);
 39
 40static void __init init_irq_default_affinity(void)
 41{
 42#ifdef CONFIG_CPUMASK_OFFSTACK
 43	if (!irq_default_affinity)
 44		zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
 45#endif
 46	if (cpumask_empty(irq_default_affinity))
 47		cpumask_setall(irq_default_affinity);
 48}
 49#else
 50static void __init init_irq_default_affinity(void)
 51{
 52}
 53#endif
 54
 55#ifdef CONFIG_SMP
 56static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
 57{
 58	if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
 59				     gfp, node))
 60		return -ENOMEM;
 61
 
 
 
 
 
 
 
 
 62#ifdef CONFIG_GENERIC_PENDING_IRQ
 63	if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
 
 
 
 64		free_cpumask_var(desc->irq_common_data.affinity);
 65		return -ENOMEM;
 66	}
 67#endif
 68	return 0;
 69}
 70
 71static void desc_smp_init(struct irq_desc *desc, int node)
 
 72{
 73	cpumask_copy(desc->irq_common_data.affinity, irq_default_affinity);
 
 
 
 74#ifdef CONFIG_GENERIC_PENDING_IRQ
 75	cpumask_clear(desc->pending_mask);
 76#endif
 77#ifdef CONFIG_NUMA
 78	desc->irq_common_data.node = node;
 79#endif
 80}
 81
 
 
 
 
 
 
 
 
 
 
 
 82#else
 83static inline int
 84alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
 85static inline void desc_smp_init(struct irq_desc *desc, int node) { }
 
 
 86#endif
 87
 88static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
 89		struct module *owner)
 90{
 91	int cpu;
 92
 93	desc->irq_common_data.handler_data = NULL;
 94	desc->irq_common_data.msi_desc = NULL;
 95
 96	desc->irq_data.common = &desc->irq_common_data;
 97	desc->irq_data.irq = irq;
 98	desc->irq_data.chip = &no_irq_chip;
 99	desc->irq_data.chip_data = NULL;
100	irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
101	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
 
102	desc->handle_irq = handle_bad_irq;
103	desc->depth = 1;
104	desc->irq_count = 0;
105	desc->irqs_unhandled = 0;
 
106	desc->name = NULL;
107	desc->owner = owner;
108	for_each_possible_cpu(cpu)
109		*per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
110	desc_smp_init(desc, node);
111}
112
113int nr_irqs = NR_IRQS;
114EXPORT_SYMBOL_GPL(nr_irqs);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
115
116static DEFINE_MUTEX(sparse_irq_lock);
117static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
 
 
 
 
118
119#ifdef CONFIG_SPARSE_IRQ
 
 
120
121static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
 
 
 
122
123static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
124{
125	radix_tree_insert(&irq_desc_tree, irq, desc);
 
 
 
 
 
 
126}
127
128struct irq_desc *irq_to_desc(unsigned int irq)
129{
130	return radix_tree_lookup(&irq_desc_tree, irq);
 
131}
132EXPORT_SYMBOL(irq_to_desc);
133
134static void delete_irq_desc(unsigned int irq)
135{
136	radix_tree_delete(&irq_desc_tree, irq);
 
137}
138
139#ifdef CONFIG_SMP
140static void free_masks(struct irq_desc *desc)
 
 
 
 
 
 
141{
142#ifdef CONFIG_GENERIC_PENDING_IRQ
143	free_cpumask_var(desc->pending_mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
144#endif
145	free_cpumask_var(desc->irq_common_data.affinity);
 
146}
147#else
148static inline void free_masks(struct irq_desc *desc) { }
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
149#endif
150
151void irq_lock_sparse(void)
152{
153	mutex_lock(&sparse_irq_lock);
154}
155
156void irq_unlock_sparse(void)
157{
158	mutex_unlock(&sparse_irq_lock);
159}
160
161static struct irq_desc *alloc_desc(int irq, int node, struct module *owner)
 
 
162{
163	struct irq_desc *desc;
164	gfp_t gfp = GFP_KERNEL;
165
166	desc = kzalloc_node(sizeof(*desc), gfp, node);
167	if (!desc)
168		return NULL;
169	/* allocate based on nr_cpu_ids */
170	desc->kstat_irqs = alloc_percpu(unsigned int);
171	if (!desc->kstat_irqs)
172		goto err_desc;
173
174	if (alloc_masks(desc, gfp, node))
175		goto err_kstat;
176
177	raw_spin_lock_init(&desc->lock);
178	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
179	init_rcu_head(&desc->rcu);
180
181	desc_set_defaults(irq, desc, node, owner);
182
183	return desc;
 
 
 
 
 
184
185err_kstat:
186	free_percpu(desc->kstat_irqs);
187err_desc:
188	kfree(desc);
189	return NULL;
190}
191
192static void delayed_free_desc(struct rcu_head *rhp)
193{
194	struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
195
196	free_masks(desc);
197	free_percpu(desc->kstat_irqs);
198	kfree(desc);
199}
200
201static void free_desc(unsigned int irq)
202{
203	struct irq_desc *desc = irq_to_desc(irq);
204
 
205	unregister_irq_proc(irq, desc);
206
207	/*
208	 * sparse_irq_lock protects also show_interrupts() and
209	 * kstat_irq_usr(). Once we deleted the descriptor from the
210	 * sparse tree we can free it. Access in proc will fail to
211	 * lookup the descriptor.
 
 
 
212	 */
213	mutex_lock(&sparse_irq_lock);
214	delete_irq_desc(irq);
215	mutex_unlock(&sparse_irq_lock);
216
217	/*
218	 * We free the descriptor, masks and stat fields via RCU. That
219	 * allows demultiplex interrupts to do rcu based management of
220	 * the child interrupts.
 
221	 */
222	call_rcu(&desc->rcu, delayed_free_desc);
223}
224
225static int alloc_descs(unsigned int start, unsigned int cnt, int node,
 
226		       struct module *owner)
227{
228	struct irq_desc *desc;
229	int i;
230
 
 
 
 
 
 
 
 
231	for (i = 0; i < cnt; i++) {
232		desc = alloc_desc(start + i, node, owner);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
233		if (!desc)
234			goto err;
235		mutex_lock(&sparse_irq_lock);
236		irq_insert_desc(start + i, desc);
237		mutex_unlock(&sparse_irq_lock);
 
238	}
239	return start;
240
241err:
242	for (i--; i >= 0; i--)
243		free_desc(start + i);
244
245	mutex_lock(&sparse_irq_lock);
246	bitmap_clear(allocated_irqs, start, cnt);
247	mutex_unlock(&sparse_irq_lock);
248	return -ENOMEM;
249}
250
251static int irq_expand_nr_irqs(unsigned int nr)
252{
253	if (nr > IRQ_BITMAP_BITS)
254		return -ENOMEM;
255	nr_irqs = nr;
256	return 0;
257}
258
259int __init early_irq_init(void)
260{
261	int i, initcnt, node = first_online_node;
262	struct irq_desc *desc;
263
264	init_irq_default_affinity();
265
266	/* Let arch update nr_irqs and return the nr of preallocated irqs */
267	initcnt = arch_probe_nr_irqs();
268	printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
 
269
270	if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
271		nr_irqs = IRQ_BITMAP_BITS;
272
273	if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
274		initcnt = IRQ_BITMAP_BITS;
275
276	if (initcnt > nr_irqs)
277		nr_irqs = initcnt;
278
279	for (i = 0; i < initcnt; i++) {
280		desc = alloc_desc(i, node, NULL);
281		set_bit(i, allocated_irqs);
282		irq_insert_desc(i, desc);
283	}
284	return arch_early_irq_init();
285}
286
287#else /* !CONFIG_SPARSE_IRQ */
288
289struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
290	[0 ... NR_IRQS-1] = {
291		.handle_irq	= handle_bad_irq,
292		.depth		= 1,
293		.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
294	}
295};
296
297int __init early_irq_init(void)
298{
299	int count, i, node = first_online_node;
300	struct irq_desc *desc;
301
302	init_irq_default_affinity();
303
304	printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
305
306	desc = irq_desc;
307	count = ARRAY_SIZE(irq_desc);
308
309	for (i = 0; i < count; i++) {
310		desc[i].kstat_irqs = alloc_percpu(unsigned int);
311		alloc_masks(&desc[i], GFP_KERNEL, node);
312		raw_spin_lock_init(&desc[i].lock);
313		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
314		desc_set_defaults(i, &desc[i], node, NULL);
315	}
 
316	return arch_early_irq_init();
 
 
 
 
 
 
 
 
317}
318
319struct irq_desc *irq_to_desc(unsigned int irq)
320{
321	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
322}
323EXPORT_SYMBOL(irq_to_desc);
324
325static void free_desc(unsigned int irq)
326{
327	struct irq_desc *desc = irq_to_desc(irq);
328	unsigned long flags;
329
330	raw_spin_lock_irqsave(&desc->lock, flags);
331	desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL);
332	raw_spin_unlock_irqrestore(&desc->lock, flags);
 
333}
334
335static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
 
336			      struct module *owner)
337{
338	u32 i;
339
340	for (i = 0; i < cnt; i++) {
341		struct irq_desc *desc = irq_to_desc(start + i);
342
343		desc->owner = owner;
 
344	}
345	return start;
346}
347
348static int irq_expand_nr_irqs(unsigned int nr)
349{
350	return -ENOMEM;
351}
352
353void irq_mark_irq(unsigned int irq)
354{
355	mutex_lock(&sparse_irq_lock);
356	bitmap_set(allocated_irqs, irq, 1);
357	mutex_unlock(&sparse_irq_lock);
358}
359
360#ifdef CONFIG_GENERIC_IRQ_LEGACY
361void irq_init_desc(unsigned int irq)
362{
363	free_desc(irq);
364}
365#endif
366
367#endif /* !CONFIG_SPARSE_IRQ */
368
369/**
370 * generic_handle_irq - Invoke the handler for a particular irq
371 * @irq:	The irq number to handle
372 *
373 */
374int generic_handle_irq(unsigned int irq)
375{
376	struct irq_desc *desc = irq_to_desc(irq);
377
378	if (!desc)
379		return -EINVAL;
 
 
 
 
 
380	generic_handle_irq_desc(desc);
381	return 0;
382}
383EXPORT_SYMBOL_GPL(generic_handle_irq);
384
385#ifdef CONFIG_HANDLE_DOMAIN_IRQ
386/**
387 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
388 * @domain:	The domain where to perform the lookup
389 * @hwirq:	The HW irq number to convert to a logical one
390 * @lookup:	Whether to perform the domain lookup or not
391 * @regs:	Register file coming from the low-level handling code
392 *
393 * Returns:	0 on success, or -EINVAL if conversion has failed
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
394 */
395int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
396			bool lookup, struct pt_regs *regs)
397{
398	struct pt_regs *old_regs = set_irq_regs(regs);
399	unsigned int irq = hwirq;
400	int ret = 0;
401
402	irq_enter();
 
 
 
 
 
403
404#ifdef CONFIG_IRQ_DOMAIN
405	if (lookup)
406		irq = irq_find_mapping(domain, hwirq);
407#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
408
409	/*
410	 * Some hardware gives randomly wrong interrupts.  Rather
411	 * than crashing, do something sensible.
412	 */
413	if (unlikely(!irq || irq >= nr_irqs)) {
414		ack_bad_irq(irq);
415		ret = -EINVAL;
416	} else {
417		generic_handle_irq(irq);
418	}
 
 
 
 
 
 
419
420	irq_exit();
421	set_irq_regs(old_regs);
 
422	return ret;
423}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
424#endif
425
426/* Dynamic interrupt handling */
427
428/**
429 * irq_free_descs - free irq descriptors
430 * @from:	Start of descriptor range
431 * @cnt:	Number of consecutive irqs to free
432 */
433void irq_free_descs(unsigned int from, unsigned int cnt)
434{
435	int i;
436
437	if (from >= nr_irqs || (from + cnt) > nr_irqs)
438		return;
439
 
440	for (i = 0; i < cnt; i++)
441		free_desc(from + i);
442
443	mutex_lock(&sparse_irq_lock);
444	bitmap_clear(allocated_irqs, from, cnt);
445	mutex_unlock(&sparse_irq_lock);
446}
447EXPORT_SYMBOL_GPL(irq_free_descs);
448
449/**
450 * irq_alloc_descs - allocate and initialize a range of irq descriptors
451 * @irq:	Allocate for specific irq number if irq >= 0
452 * @from:	Start the search from this irq number
453 * @cnt:	Number of consecutive irqs to allocate.
454 * @node:	Preferred node on which the irq descriptor should be allocated
455 * @owner:	Owning module (can be NULL)
 
 
 
456 *
457 * Returns the first irq number or error code
458 */
459int __ref
460__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
461		  struct module *owner)
462{
463	int start, ret;
464
465	if (!cnt)
466		return -EINVAL;
467
468	if (irq >= 0) {
469		if (from > irq)
470			return -EINVAL;
471		from = irq;
472	} else {
473		/*
474		 * For interrupts which are freely allocated the
475		 * architecture can force a lower bound to the @from
476		 * argument. x86 uses this to exclude the GSI space.
477		 */
478		from = arch_dynirq_lower_bound(from);
479	}
480
481	mutex_lock(&sparse_irq_lock);
482
483	start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
484					   from, cnt, 0);
485	ret = -EEXIST;
486	if (irq >=0 && start != irq)
487		goto err;
488
489	if (start + cnt > nr_irqs) {
490		ret = irq_expand_nr_irqs(start + cnt);
491		if (ret)
492			goto err;
493	}
494
495	bitmap_set(allocated_irqs, start, cnt);
496	mutex_unlock(&sparse_irq_lock);
497	return alloc_descs(start, cnt, node, owner);
498
499err:
500	mutex_unlock(&sparse_irq_lock);
501	return ret;
502}
503EXPORT_SYMBOL_GPL(__irq_alloc_descs);
504
505#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
506/**
507 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
508 * @cnt:	number of interrupts to allocate
509 * @node:	node on which to allocate
510 *
511 * Returns an interrupt number > 0 or 0, if the allocation fails.
512 */
513unsigned int irq_alloc_hwirqs(int cnt, int node)
514{
515	int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL);
516
517	if (irq < 0)
518		return 0;
519
520	for (i = irq; cnt > 0; i++, cnt--) {
521		if (arch_setup_hwirq(i, node))
522			goto err;
523		irq_clear_status_flags(i, _IRQ_NOREQUEST);
524	}
525	return irq;
526
527err:
528	for (i--; i >= irq; i--) {
529		irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
530		arch_teardown_hwirq(i);
531	}
532	irq_free_descs(irq, cnt);
533	return 0;
534}
535EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
536
537/**
538 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
539 * @from:	Free from irq number
540 * @cnt:	number of interrupts to free
541 *
542 */
543void irq_free_hwirqs(unsigned int from, int cnt)
544{
545	int i, j;
546
547	for (i = from, j = cnt; j > 0; i++, j--) {
548		irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
549		arch_teardown_hwirq(i);
550	}
551	irq_free_descs(from, cnt);
552}
553EXPORT_SYMBOL_GPL(irq_free_hwirqs);
554#endif
555
556/**
557 * irq_get_next_irq - get next allocated irq number
558 * @offset:	where to start the search
559 *
560 * Returns next irq number after offset or nr_irqs if none is found.
561 */
562unsigned int irq_get_next_irq(unsigned int offset)
563{
564	return find_next_bit(allocated_irqs, nr_irqs, offset);
565}
566
567struct irq_desc *
568__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
569		    unsigned int check)
570{
571	struct irq_desc *desc = irq_to_desc(irq);
572
573	if (desc) {
574		if (check & _IRQ_DESC_CHECK) {
575			if ((check & _IRQ_DESC_PERCPU) &&
576			    !irq_settings_is_per_cpu_devid(desc))
577				return NULL;
578
579			if (!(check & _IRQ_DESC_PERCPU) &&
580			    irq_settings_is_per_cpu_devid(desc))
581				return NULL;
582		}
583
584		if (bus)
585			chip_bus_lock(desc);
586		raw_spin_lock_irqsave(&desc->lock, *flags);
587	}
588	return desc;
589}
590
591void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
 
592{
593	raw_spin_unlock_irqrestore(&desc->lock, flags);
594	if (bus)
595		chip_bus_sync_unlock(desc);
596}
597
598int irq_set_percpu_devid(unsigned int irq)
 
599{
600	struct irq_desc *desc = irq_to_desc(irq);
601
602	if (!desc)
603		return -EINVAL;
604
605	if (desc->percpu_enabled)
606		return -EINVAL;
607
608	desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
609
610	if (!desc->percpu_enabled)
611		return -ENOMEM;
612
 
 
613	irq_set_percpu_devid_flags(irq);
614	return 0;
615}
616
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
617void kstat_incr_irq_this_cpu(unsigned int irq)
618{
619	kstat_incr_irqs_this_cpu(irq_to_desc(irq));
620}
621
622/**
623 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
624 * @irq:	The interrupt number
625 * @cpu:	The cpu number
626 *
627 * Returns the sum of interrupt counts on @cpu since boot for
628 * @irq. The caller must ensure that the interrupt is not removed
629 * concurrently.
630 */
631unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
632{
633	struct irq_desc *desc = irq_to_desc(irq);
634
635	return desc && desc->kstat_irqs ?
636			*per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
637}
638
639/**
640 * kstat_irqs - Get the statistics for an interrupt
641 * @irq:	The interrupt number
642 *
643 * Returns the sum of interrupt counts on all cpus since boot for
644 * @irq. The caller must ensure that the interrupt is not removed
645 * concurrently.
646 */
647unsigned int kstat_irqs(unsigned int irq)
648{
649	struct irq_desc *desc = irq_to_desc(irq);
650	int cpu;
651	unsigned int sum = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
652
653	if (!desc || !desc->kstat_irqs)
654		return 0;
655	for_each_possible_cpu(cpu)
656		sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
657	return sum;
 
 
 
 
 
 
 
 
 
 
 
 
658}
659
 
 
 
 
 
 
 
 
 
 
 
660/**
661 * kstat_irqs_usr - Get the statistics for an interrupt
662 * @irq:	The interrupt number
663 *
664 * Returns the sum of interrupt counts on all cpus since boot for
665 * @irq. Contrary to kstat_irqs() this can be called from any
666 * preemptible context. It's protected against concurrent removal of
667 * an interrupt descriptor when sparse irqs are enabled.
 
668 */
669unsigned int kstat_irqs_usr(unsigned int irq)
670{
671	unsigned int sum;
672
673	irq_lock_sparse();
674	sum = kstat_irqs(irq);
675	irq_unlock_sparse();
676	return sum;
677}
v6.13.7
   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#include <linux/string_choices.h>
  19
  20#include "internals.h"
  21
  22/*
  23 * lockdep: we want to handle all irq_desc locks as a single lock-class:
  24 */
  25static struct lock_class_key irq_desc_lock_class;
  26
  27#if defined(CONFIG_SMP)
  28static int __init irq_affinity_setup(char *str)
  29{
  30	alloc_bootmem_cpumask_var(&irq_default_affinity);
  31	cpulist_parse(str, irq_default_affinity);
  32	/*
  33	 * Set at least the boot cpu. We don't want to end up with
  34	 * bugreports caused by random commandline masks
  35	 */
  36	cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
  37	return 1;
  38}
  39__setup("irqaffinity=", irq_affinity_setup);
  40
  41static void __init init_irq_default_affinity(void)
  42{
  43	if (!cpumask_available(irq_default_affinity))
 
  44		zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
 
  45	if (cpumask_empty(irq_default_affinity))
  46		cpumask_setall(irq_default_affinity);
  47}
  48#else
  49static void __init init_irq_default_affinity(void)
  50{
  51}
  52#endif
  53
  54#ifdef CONFIG_SMP
  55static int alloc_masks(struct irq_desc *desc, int node)
  56{
  57	if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
  58				     GFP_KERNEL, node))
  59		return -ENOMEM;
  60
  61#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
  62	if (!zalloc_cpumask_var_node(&desc->irq_common_data.effective_affinity,
  63				     GFP_KERNEL, node)) {
  64		free_cpumask_var(desc->irq_common_data.affinity);
  65		return -ENOMEM;
  66	}
  67#endif
  68
  69#ifdef CONFIG_GENERIC_PENDING_IRQ
  70	if (!zalloc_cpumask_var_node(&desc->pending_mask, GFP_KERNEL, node)) {
  71#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
  72		free_cpumask_var(desc->irq_common_data.effective_affinity);
  73#endif
  74		free_cpumask_var(desc->irq_common_data.affinity);
  75		return -ENOMEM;
  76	}
  77#endif
  78	return 0;
  79}
  80
  81static void desc_smp_init(struct irq_desc *desc, int node,
  82			  const struct cpumask *affinity)
  83{
  84	if (!affinity)
  85		affinity = irq_default_affinity;
  86	cpumask_copy(desc->irq_common_data.affinity, affinity);
  87
  88#ifdef CONFIG_GENERIC_PENDING_IRQ
  89	cpumask_clear(desc->pending_mask);
  90#endif
  91#ifdef CONFIG_NUMA
  92	desc->irq_common_data.node = node;
  93#endif
  94}
  95
  96static void free_masks(struct irq_desc *desc)
  97{
  98#ifdef CONFIG_GENERIC_PENDING_IRQ
  99	free_cpumask_var(desc->pending_mask);
 100#endif
 101	free_cpumask_var(desc->irq_common_data.affinity);
 102#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
 103	free_cpumask_var(desc->irq_common_data.effective_affinity);
 104#endif
 105}
 106
 107#else
 108static inline int
 109alloc_masks(struct irq_desc *desc, int node) { return 0; }
 110static inline void
 111desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
 112static inline void free_masks(struct irq_desc *desc) { }
 113#endif
 114
 115static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
 116			      const struct cpumask *affinity, struct module *owner)
 117{
 118	int cpu;
 119
 120	desc->irq_common_data.handler_data = NULL;
 121	desc->irq_common_data.msi_desc = NULL;
 122
 123	desc->irq_data.common = &desc->irq_common_data;
 124	desc->irq_data.irq = irq;
 125	desc->irq_data.chip = &no_irq_chip;
 126	desc->irq_data.chip_data = NULL;
 127	irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
 128	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
 129	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
 130	desc->handle_irq = handle_bad_irq;
 131	desc->depth = 1;
 132	desc->irq_count = 0;
 133	desc->irqs_unhandled = 0;
 134	desc->tot_count = 0;
 135	desc->name = NULL;
 136	desc->owner = owner;
 137	for_each_possible_cpu(cpu)
 138		*per_cpu_ptr(desc->kstat_irqs, cpu) = (struct irqstat) { };
 139	desc_smp_init(desc, node, affinity);
 140}
 141
 142static unsigned int nr_irqs = NR_IRQS;
 143
 144/**
 145 * irq_get_nr_irqs() - Number of interrupts supported by the system.
 146 */
 147unsigned int irq_get_nr_irqs(void)
 148{
 149	return nr_irqs;
 150}
 151EXPORT_SYMBOL_GPL(irq_get_nr_irqs);
 152
 153/**
 154 * irq_set_nr_irqs() - Set the number of interrupts supported by the system.
 155 * @nr: New number of interrupts.
 156 *
 157 * Return: @nr.
 158 */
 159unsigned int irq_set_nr_irqs(unsigned int nr)
 160{
 161	nr_irqs = nr;
 162
 163	return nr;
 164}
 165EXPORT_SYMBOL_GPL(irq_set_nr_irqs);
 166
 167static DEFINE_MUTEX(sparse_irq_lock);
 168static struct maple_tree sparse_irqs = MTREE_INIT_EXT(sparse_irqs,
 169					MT_FLAGS_ALLOC_RANGE |
 170					MT_FLAGS_LOCK_EXTERN |
 171					MT_FLAGS_USE_RCU,
 172					sparse_irq_lock);
 173
 174static int irq_find_free_area(unsigned int from, unsigned int cnt)
 175{
 176	MA_STATE(mas, &sparse_irqs, 0, 0);
 177
 178	if (mas_empty_area(&mas, from, MAX_SPARSE_IRQS, cnt))
 179		return -ENOSPC;
 180	return mas.index;
 181}
 182
 183static unsigned int irq_find_at_or_after(unsigned int offset)
 184{
 185	unsigned long index = offset;
 186	struct irq_desc *desc;
 187
 188	guard(rcu)();
 189	desc = mt_find(&sparse_irqs, &index, nr_irqs);
 190
 191	return desc ? irq_desc_get_irq(desc) : nr_irqs;
 192}
 193
 194static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
 195{
 196	MA_STATE(mas, &sparse_irqs, irq, irq);
 197	WARN_ON(mas_store_gfp(&mas, desc, GFP_KERNEL) != 0);
 198}
 
 199
 200static void delete_irq_desc(unsigned int irq)
 201{
 202	MA_STATE(mas, &sparse_irqs, irq, irq);
 203	mas_erase(&mas);
 204}
 205
 206#ifdef CONFIG_SPARSE_IRQ
 207static const struct kobj_type irq_kobj_type;
 208#endif
 209
 210static int init_desc(struct irq_desc *desc, int irq, int node,
 211		     unsigned int flags,
 212		     const struct cpumask *affinity,
 213		     struct module *owner)
 214{
 215	desc->kstat_irqs = alloc_percpu(struct irqstat);
 216	if (!desc->kstat_irqs)
 217		return -ENOMEM;
 218
 219	if (alloc_masks(desc, node)) {
 220		free_percpu(desc->kstat_irqs);
 221		return -ENOMEM;
 222	}
 223
 224	raw_spin_lock_init(&desc->lock);
 225	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
 226	mutex_init(&desc->request_mutex);
 227	init_waitqueue_head(&desc->wait_for_threads);
 228	desc_set_defaults(irq, desc, node, affinity, owner);
 229	irqd_set(&desc->irq_data, flags);
 230	irq_resend_init(desc);
 231#ifdef CONFIG_SPARSE_IRQ
 232	kobject_init(&desc->kobj, &irq_kobj_type);
 233	init_rcu_head(&desc->rcu);
 234#endif
 235
 236	return 0;
 237}
 238
 239#ifdef CONFIG_SPARSE_IRQ
 240
 241static void irq_kobj_release(struct kobject *kobj);
 242
 243#ifdef CONFIG_SYSFS
 244static struct kobject *irq_kobj_base;
 245
 246#define IRQ_ATTR_RO(_name) \
 247static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 248
 249static ssize_t per_cpu_count_show(struct kobject *kobj,
 250				  struct kobj_attribute *attr, char *buf)
 251{
 252	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 253	ssize_t ret = 0;
 254	char *p = "";
 255	int cpu;
 256
 257	for_each_possible_cpu(cpu) {
 258		unsigned int c = irq_desc_kstat_cpu(desc, cpu);
 259
 260		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
 261		p = ",";
 262	}
 263
 264	ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 265	return ret;
 266}
 267IRQ_ATTR_RO(per_cpu_count);
 268
 269static ssize_t chip_name_show(struct kobject *kobj,
 270			      struct kobj_attribute *attr, char *buf)
 271{
 272	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 273	ssize_t ret = 0;
 274
 275	raw_spin_lock_irq(&desc->lock);
 276	if (desc->irq_data.chip && desc->irq_data.chip->name) {
 277		ret = scnprintf(buf, PAGE_SIZE, "%s\n",
 278				desc->irq_data.chip->name);
 279	}
 280	raw_spin_unlock_irq(&desc->lock);
 281
 282	return ret;
 283}
 284IRQ_ATTR_RO(chip_name);
 285
 286static ssize_t hwirq_show(struct kobject *kobj,
 287			  struct kobj_attribute *attr, char *buf)
 288{
 289	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 290	ssize_t ret = 0;
 291
 292	raw_spin_lock_irq(&desc->lock);
 293	if (desc->irq_data.domain)
 294		ret = sprintf(buf, "%lu\n", desc->irq_data.hwirq);
 295	raw_spin_unlock_irq(&desc->lock);
 296
 297	return ret;
 298}
 299IRQ_ATTR_RO(hwirq);
 300
 301static ssize_t type_show(struct kobject *kobj,
 302			 struct kobj_attribute *attr, char *buf)
 303{
 304	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 305	ssize_t ret = 0;
 306
 307	raw_spin_lock_irq(&desc->lock);
 308	ret = sprintf(buf, "%s\n",
 309		      irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
 310	raw_spin_unlock_irq(&desc->lock);
 311
 312	return ret;
 313
 314}
 315IRQ_ATTR_RO(type);
 316
 317static ssize_t wakeup_show(struct kobject *kobj,
 318			   struct kobj_attribute *attr, char *buf)
 319{
 320	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 321	ssize_t ret = 0;
 322
 323	raw_spin_lock_irq(&desc->lock);
 324	ret = sprintf(buf, "%s\n", str_enabled_disabled(irqd_is_wakeup_set(&desc->irq_data)));
 325	raw_spin_unlock_irq(&desc->lock);
 326
 327	return ret;
 328
 329}
 330IRQ_ATTR_RO(wakeup);
 331
 332static ssize_t name_show(struct kobject *kobj,
 333			 struct kobj_attribute *attr, char *buf)
 334{
 335	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 336	ssize_t ret = 0;
 337
 338	raw_spin_lock_irq(&desc->lock);
 339	if (desc->name)
 340		ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
 341	raw_spin_unlock_irq(&desc->lock);
 342
 343	return ret;
 344}
 345IRQ_ATTR_RO(name);
 346
 347static ssize_t actions_show(struct kobject *kobj,
 348			    struct kobj_attribute *attr, char *buf)
 349{
 350	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 351	struct irqaction *action;
 352	ssize_t ret = 0;
 353	char *p = "";
 354
 355	raw_spin_lock_irq(&desc->lock);
 356	for_each_action_of_desc(desc, action) {
 357		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
 358				 p, action->name);
 359		p = ",";
 360	}
 361	raw_spin_unlock_irq(&desc->lock);
 362
 363	if (ret)
 364		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 365
 366	return ret;
 367}
 368IRQ_ATTR_RO(actions);
 369
 370static struct attribute *irq_attrs[] = {
 371	&per_cpu_count_attr.attr,
 372	&chip_name_attr.attr,
 373	&hwirq_attr.attr,
 374	&type_attr.attr,
 375	&wakeup_attr.attr,
 376	&name_attr.attr,
 377	&actions_attr.attr,
 378	NULL
 379};
 380ATTRIBUTE_GROUPS(irq);
 381
 382static const struct kobj_type irq_kobj_type = {
 383	.release	= irq_kobj_release,
 384	.sysfs_ops	= &kobj_sysfs_ops,
 385	.default_groups = irq_groups,
 386};
 387
 388static void irq_sysfs_add(int irq, struct irq_desc *desc)
 389{
 390	if (irq_kobj_base) {
 391		/*
 392		 * Continue even in case of failure as this is nothing
 393		 * crucial and failures in the late irq_sysfs_init()
 394		 * cannot be rolled back.
 395		 */
 396		if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
 397			pr_warn("Failed to add kobject for irq %d\n", irq);
 398		else
 399			desc->istate |= IRQS_SYSFS;
 400	}
 401}
 402
 403static void irq_sysfs_del(struct irq_desc *desc)
 404{
 405	/*
 406	 * Only invoke kobject_del() when kobject_add() was successfully
 407	 * invoked for the descriptor. This covers both early boot, where
 408	 * sysfs is not initialized yet, and the case of a failed
 409	 * kobject_add() invocation.
 410	 */
 411	if (desc->istate & IRQS_SYSFS)
 412		kobject_del(&desc->kobj);
 413}
 414
 415static int __init irq_sysfs_init(void)
 416{
 417	struct irq_desc *desc;
 418	int irq;
 419
 420	/* Prevent concurrent irq alloc/free */
 421	irq_lock_sparse();
 422
 423	irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
 424	if (!irq_kobj_base) {
 425		irq_unlock_sparse();
 426		return -ENOMEM;
 427	}
 428
 429	/* Add the already allocated interrupts */
 430	for_each_irq_desc(irq, desc)
 431		irq_sysfs_add(irq, desc);
 432	irq_unlock_sparse();
 433
 434	return 0;
 435}
 436postcore_initcall(irq_sysfs_init);
 437
 438#else /* !CONFIG_SYSFS */
 439
 440static const struct kobj_type irq_kobj_type = {
 441	.release	= irq_kobj_release,
 442};
 443
 444static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
 445static void irq_sysfs_del(struct irq_desc *desc) {}
 446
 447#endif /* CONFIG_SYSFS */
 448
 449struct irq_desc *irq_to_desc(unsigned int irq)
 450{
 451	return mtree_load(&sparse_irqs, irq);
 452}
 453#ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
 454EXPORT_SYMBOL_GPL(irq_to_desc);
 455#endif
 456
 457void irq_lock_sparse(void)
 458{
 459	mutex_lock(&sparse_irq_lock);
 460}
 461
 462void irq_unlock_sparse(void)
 463{
 464	mutex_unlock(&sparse_irq_lock);
 465}
 466
 467static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
 468				   const struct cpumask *affinity,
 469				   struct module *owner)
 470{
 471	struct irq_desc *desc;
 472	int ret;
 473
 474	desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
 475	if (!desc)
 476		return NULL;
 
 
 
 
 
 
 
 477
 478	ret = init_desc(desc, irq, node, flags, affinity, owner);
 479	if (unlikely(ret)) {
 480		kfree(desc);
 481		return NULL;
 482	}
 483
 484	return desc;
 485}
 486
 487static void irq_kobj_release(struct kobject *kobj)
 488{
 489	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 490
 491	free_masks(desc);
 492	free_percpu(desc->kstat_irqs);
 
 493	kfree(desc);
 
 494}
 495
 496static void delayed_free_desc(struct rcu_head *rhp)
 497{
 498	struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
 499
 500	kobject_put(&desc->kobj);
 
 
 501}
 502
 503static void free_desc(unsigned int irq)
 504{
 505	struct irq_desc *desc = irq_to_desc(irq);
 506
 507	irq_remove_debugfs_entry(desc);
 508	unregister_irq_proc(irq, desc);
 509
 510	/*
 511	 * sparse_irq_lock protects also show_interrupts() and
 512	 * kstat_irq_usr(). Once we deleted the descriptor from the
 513	 * sparse tree we can free it. Access in proc will fail to
 514	 * lookup the descriptor.
 515	 *
 516	 * The sysfs entry must be serialized against a concurrent
 517	 * irq_sysfs_init() as well.
 518	 */
 519	irq_sysfs_del(desc);
 520	delete_irq_desc(irq);
 
 521
 522	/*
 523	 * We free the descriptor, masks and stat fields via RCU. That
 524	 * allows demultiplex interrupts to do rcu based management of
 525	 * the child interrupts.
 526	 * This also allows us to use rcu in kstat_irqs_usr().
 527	 */
 528	call_rcu(&desc->rcu, delayed_free_desc);
 529}
 530
 531static int alloc_descs(unsigned int start, unsigned int cnt, int node,
 532		       const struct irq_affinity_desc *affinity,
 533		       struct module *owner)
 534{
 535	struct irq_desc *desc;
 536	int i;
 537
 538	/* Validate affinity mask(s) */
 539	if (affinity) {
 540		for (i = 0; i < cnt; i++) {
 541			if (cpumask_empty(&affinity[i].mask))
 542				return -EINVAL;
 543		}
 544	}
 545
 546	for (i = 0; i < cnt; i++) {
 547		const struct cpumask *mask = NULL;
 548		unsigned int flags = 0;
 549
 550		if (affinity) {
 551			if (affinity->is_managed) {
 552				flags = IRQD_AFFINITY_MANAGED |
 553					IRQD_MANAGED_SHUTDOWN;
 554			}
 555			flags |= IRQD_AFFINITY_SET;
 556			mask = &affinity->mask;
 557			node = cpu_to_node(cpumask_first(mask));
 558			affinity++;
 559		}
 560
 561		desc = alloc_desc(start + i, node, flags, mask, owner);
 562		if (!desc)
 563			goto err;
 
 564		irq_insert_desc(start + i, desc);
 565		irq_sysfs_add(start + i, desc);
 566		irq_add_debugfs_entry(start + i, desc);
 567	}
 568	return start;
 569
 570err:
 571	for (i--; i >= 0; i--)
 572		free_desc(start + i);
 
 
 
 
 573	return -ENOMEM;
 574}
 575
 576static int irq_expand_nr_irqs(unsigned int nr)
 577{
 578	if (nr > MAX_SPARSE_IRQS)
 579		return -ENOMEM;
 580	nr_irqs = nr;
 581	return 0;
 582}
 583
 584int __init early_irq_init(void)
 585{
 586	int i, initcnt, node = first_online_node;
 587	struct irq_desc *desc;
 588
 589	init_irq_default_affinity();
 590
 591	/* Let arch update nr_irqs and return the nr of preallocated irqs */
 592	initcnt = arch_probe_nr_irqs();
 593	printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
 594	       NR_IRQS, nr_irqs, initcnt);
 595
 596	if (WARN_ON(nr_irqs > MAX_SPARSE_IRQS))
 597		nr_irqs = MAX_SPARSE_IRQS;
 598
 599	if (WARN_ON(initcnt > MAX_SPARSE_IRQS))
 600		initcnt = MAX_SPARSE_IRQS;
 601
 602	if (initcnt > nr_irqs)
 603		nr_irqs = initcnt;
 604
 605	for (i = 0; i < initcnt; i++) {
 606		desc = alloc_desc(i, node, 0, NULL, NULL);
 
 607		irq_insert_desc(i, desc);
 608	}
 609	return arch_early_irq_init();
 610}
 611
 612#else /* !CONFIG_SPARSE_IRQ */
 613
 614struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
 615	[0 ... NR_IRQS-1] = {
 616		.handle_irq	= handle_bad_irq,
 617		.depth		= 1,
 618		.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
 619	}
 620};
 621
 622int __init early_irq_init(void)
 623{
 624	int count, i, node = first_online_node;
 625	int ret;
 626
 627	init_irq_default_affinity();
 628
 629	printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
 630
 
 631	count = ARRAY_SIZE(irq_desc);
 632
 633	for (i = 0; i < count; i++) {
 634		ret = init_desc(irq_desc + i, i, node, 0, NULL, NULL);
 635		if (unlikely(ret))
 636			goto __free_desc_res;
 
 
 637	}
 638
 639	return arch_early_irq_init();
 640
 641__free_desc_res:
 642	while (--i >= 0) {
 643		free_masks(irq_desc + i);
 644		free_percpu(irq_desc[i].kstat_irqs);
 645	}
 646
 647	return ret;
 648}
 649
 650struct irq_desc *irq_to_desc(unsigned int irq)
 651{
 652	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
 653}
 654EXPORT_SYMBOL(irq_to_desc);
 655
 656static void free_desc(unsigned int irq)
 657{
 658	struct irq_desc *desc = irq_to_desc(irq);
 659	unsigned long flags;
 660
 661	raw_spin_lock_irqsave(&desc->lock, flags);
 662	desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
 663	raw_spin_unlock_irqrestore(&desc->lock, flags);
 664	delete_irq_desc(irq);
 665}
 666
 667static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
 668			      const struct irq_affinity_desc *affinity,
 669			      struct module *owner)
 670{
 671	u32 i;
 672
 673	for (i = 0; i < cnt; i++) {
 674		struct irq_desc *desc = irq_to_desc(start + i);
 675
 676		desc->owner = owner;
 677		irq_insert_desc(start + i, desc);
 678	}
 679	return start;
 680}
 681
 682static int irq_expand_nr_irqs(unsigned int nr)
 683{
 684	return -ENOMEM;
 685}
 686
 687void irq_mark_irq(unsigned int irq)
 688{
 689	mutex_lock(&sparse_irq_lock);
 690	irq_insert_desc(irq, irq_desc + irq);
 691	mutex_unlock(&sparse_irq_lock);
 692}
 693
 694#ifdef CONFIG_GENERIC_IRQ_LEGACY
 695void irq_init_desc(unsigned int irq)
 696{
 697	free_desc(irq);
 698}
 699#endif
 700
 701#endif /* !CONFIG_SPARSE_IRQ */
 702
 703int handle_irq_desc(struct irq_desc *desc)
 
 
 
 
 
 704{
 705	struct irq_data *data;
 706
 707	if (!desc)
 708		return -EINVAL;
 709
 710	data = irq_desc_get_irq_data(desc);
 711	if (WARN_ON_ONCE(!in_hardirq() && handle_enforce_irqctx(data)))
 712		return -EPERM;
 713
 714	generic_handle_irq_desc(desc);
 715	return 0;
 716}
 
 717
 
 718/**
 719 * generic_handle_irq - Invoke the handler for a particular irq
 720 * @irq:	The irq number to handle
 
 
 
 721 *
 722 * Returns:	0 on success, or -EINVAL if conversion has failed
 723 *
 724 * 		This function must be called from an IRQ context with irq regs
 725 * 		initialized.
 726  */
 727int generic_handle_irq(unsigned int irq)
 728{
 729	return handle_irq_desc(irq_to_desc(irq));
 730}
 731EXPORT_SYMBOL_GPL(generic_handle_irq);
 732
 733/**
 734 * generic_handle_irq_safe - Invoke the handler for a particular irq from any
 735 *			     context.
 736 * @irq:	The irq number to handle
 737 *
 738 * Returns:	0 on success, a negative value on error.
 739 *
 740 * This function can be called from any context (IRQ or process context). It
 741 * will report an error if not invoked from IRQ context and the irq has been
 742 * marked to enforce IRQ-context only.
 743 */
 744int generic_handle_irq_safe(unsigned int irq)
 
 745{
 746	unsigned long flags;
 747	int ret;
 
 748
 749	local_irq_save(flags);
 750	ret = handle_irq_desc(irq_to_desc(irq));
 751	local_irq_restore(flags);
 752	return ret;
 753}
 754EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
 755
 756#ifdef CONFIG_IRQ_DOMAIN
 757/**
 758 * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
 759 *                             to a domain.
 760 * @domain:	The domain where to perform the lookup
 761 * @hwirq:	The HW irq number to convert to a logical one
 762 *
 763 * Returns:	0 on success, or -EINVAL if conversion has failed
 764 *
 765 * 		This function must be called from an IRQ context with irq regs
 766 * 		initialized.
 767 */
 768int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
 769{
 770	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 771}
 772EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
 773
 774 /**
 775 * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
 776 *			     to a domain from any context.
 777 * @domain:	The domain where to perform the lookup
 778 * @hwirq:	The HW irq number to convert to a logical one
 779 *
 780 * Returns:	0 on success, a negative value on error.
 781 *
 782 * This function can be called from any context (IRQ or process
 783 * context). If the interrupt is marked as 'enforce IRQ-context only' then
 784 * the function must be invoked from hard interrupt context.
 785 */
 786int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
 787{
 788	unsigned long flags;
 789	int ret;
 790
 791	local_irq_save(flags);
 792	ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 793	local_irq_restore(flags);
 794	return ret;
 795}
 796EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
 797
 798/**
 799 * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
 800 *                             to a domain.
 801 * @domain:	The domain where to perform the lookup
 802 * @hwirq:	The HW irq number to convert to a logical one
 803 *
 804 * Returns:	0 on success, or -EINVAL if conversion has failed
 805 *
 806 * 		This function must be called from an NMI context with irq regs
 807 * 		initialized.
 808 **/
 809int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq)
 810{
 811	WARN_ON_ONCE(!in_nmi());
 812	return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 813}
 814#endif
 815
 816/* Dynamic interrupt handling */
 817
 818/**
 819 * irq_free_descs - free irq descriptors
 820 * @from:	Start of descriptor range
 821 * @cnt:	Number of consecutive irqs to free
 822 */
 823void irq_free_descs(unsigned int from, unsigned int cnt)
 824{
 825	int i;
 826
 827	if (from >= nr_irqs || (from + cnt) > nr_irqs)
 828		return;
 829
 830	mutex_lock(&sparse_irq_lock);
 831	for (i = 0; i < cnt; i++)
 832		free_desc(from + i);
 833
 
 
 834	mutex_unlock(&sparse_irq_lock);
 835}
 836EXPORT_SYMBOL_GPL(irq_free_descs);
 837
 838/**
 839 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
 840 * @irq:	Allocate for specific irq number if irq >= 0
 841 * @from:	Start the search from this irq number
 842 * @cnt:	Number of consecutive irqs to allocate.
 843 * @node:	Preferred node on which the irq descriptor should be allocated
 844 * @owner:	Owning module (can be NULL)
 845 * @affinity:	Optional pointer to an affinity mask array of size @cnt which
 846 *		hints where the irq descriptors should be allocated and which
 847 *		default affinities to use
 848 *
 849 * Returns the first irq number or error code
 850 */
 851int __ref
 852__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 853		  struct module *owner, const struct irq_affinity_desc *affinity)
 854{
 855	int start, ret;
 856
 857	if (!cnt)
 858		return -EINVAL;
 859
 860	if (irq >= 0) {
 861		if (from > irq)
 862			return -EINVAL;
 863		from = irq;
 864	} else {
 865		/*
 866		 * For interrupts which are freely allocated the
 867		 * architecture can force a lower bound to the @from
 868		 * argument. x86 uses this to exclude the GSI space.
 869		 */
 870		from = arch_dynirq_lower_bound(from);
 871	}
 872
 873	mutex_lock(&sparse_irq_lock);
 874
 875	start = irq_find_free_area(from, cnt);
 
 876	ret = -EEXIST;
 877	if (irq >=0 && start != irq)
 878		goto unlock;
 879
 880	if (start + cnt > nr_irqs) {
 881		ret = irq_expand_nr_irqs(start + cnt);
 882		if (ret)
 883			goto unlock;
 884	}
 885	ret = alloc_descs(start, cnt, node, affinity, owner);
 886unlock:
 
 
 
 
 887	mutex_unlock(&sparse_irq_lock);
 888	return ret;
 889}
 890EXPORT_SYMBOL_GPL(__irq_alloc_descs);
 891
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 892/**
 893 * irq_get_next_irq - get next allocated irq number
 894 * @offset:	where to start the search
 895 *
 896 * Returns next irq number after offset or nr_irqs if none is found.
 897 */
 898unsigned int irq_get_next_irq(unsigned int offset)
 899{
 900	return irq_find_at_or_after(offset);
 901}
 902
 903struct irq_desc *
 904__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
 905		    unsigned int check)
 906{
 907	struct irq_desc *desc = irq_to_desc(irq);
 908
 909	if (desc) {
 910		if (check & _IRQ_DESC_CHECK) {
 911			if ((check & _IRQ_DESC_PERCPU) &&
 912			    !irq_settings_is_per_cpu_devid(desc))
 913				return NULL;
 914
 915			if (!(check & _IRQ_DESC_PERCPU) &&
 916			    irq_settings_is_per_cpu_devid(desc))
 917				return NULL;
 918		}
 919
 920		if (bus)
 921			chip_bus_lock(desc);
 922		raw_spin_lock_irqsave(&desc->lock, *flags);
 923	}
 924	return desc;
 925}
 926
 927void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
 928	__releases(&desc->lock)
 929{
 930	raw_spin_unlock_irqrestore(&desc->lock, flags);
 931	if (bus)
 932		chip_bus_sync_unlock(desc);
 933}
 934
 935int irq_set_percpu_devid_partition(unsigned int irq,
 936				   const struct cpumask *affinity)
 937{
 938	struct irq_desc *desc = irq_to_desc(irq);
 939
 940	if (!desc || desc->percpu_enabled)
 
 
 
 941		return -EINVAL;
 942
 943	desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
 944
 945	if (!desc->percpu_enabled)
 946		return -ENOMEM;
 947
 948	desc->percpu_affinity = affinity ? : cpu_possible_mask;
 949
 950	irq_set_percpu_devid_flags(irq);
 951	return 0;
 952}
 953
 954int irq_set_percpu_devid(unsigned int irq)
 955{
 956	return irq_set_percpu_devid_partition(irq, NULL);
 957}
 958
 959int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
 960{
 961	struct irq_desc *desc = irq_to_desc(irq);
 962
 963	if (!desc || !desc->percpu_enabled)
 964		return -EINVAL;
 965
 966	if (affinity)
 967		cpumask_copy(affinity, desc->percpu_affinity);
 968
 969	return 0;
 970}
 971EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
 972
 973void kstat_incr_irq_this_cpu(unsigned int irq)
 974{
 975	kstat_incr_irqs_this_cpu(irq_to_desc(irq));
 976}
 977
 978/**
 979 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
 980 * @irq:	The interrupt number
 981 * @cpu:	The cpu number
 982 *
 983 * Returns the sum of interrupt counts on @cpu since boot for
 984 * @irq. The caller must ensure that the interrupt is not removed
 985 * concurrently.
 986 */
 987unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 988{
 989	struct irq_desc *desc = irq_to_desc(irq);
 990
 991	return desc && desc->kstat_irqs ? per_cpu(desc->kstat_irqs->cnt, cpu) : 0;
 
 992}
 993
 994unsigned int kstat_irqs_desc(struct irq_desc *desc, const struct cpumask *cpumask)
 
 
 
 
 
 
 
 
 995{
 
 
 996	unsigned int sum = 0;
 997	int cpu;
 998
 999	if (!irq_settings_is_per_cpu_devid(desc) &&
1000	    !irq_settings_is_per_cpu(desc) &&
1001	    !irq_is_nmi(desc))
1002		return data_race(desc->tot_count);
1003
1004	for_each_cpu(cpu, cpumask)
1005		sum += data_race(per_cpu(desc->kstat_irqs->cnt, cpu));
1006	return sum;
1007}
1008
1009static unsigned int kstat_irqs(unsigned int irq)
1010{
1011	struct irq_desc *desc = irq_to_desc(irq);
1012
1013	if (!desc || !desc->kstat_irqs)
1014		return 0;
1015	return kstat_irqs_desc(desc, cpu_possible_mask);
1016}
1017
1018#ifdef CONFIG_GENERIC_IRQ_STAT_SNAPSHOT
1019
1020void kstat_snapshot_irqs(void)
1021{
1022	struct irq_desc *desc;
1023	unsigned int irq;
1024
1025	for_each_irq_desc(irq, desc) {
1026		if (!desc->kstat_irqs)
1027			continue;
1028		this_cpu_write(desc->kstat_irqs->ref, this_cpu_read(desc->kstat_irqs->cnt));
1029	}
1030}
1031
1032unsigned int kstat_get_irq_since_snapshot(unsigned int irq)
1033{
1034	struct irq_desc *desc = irq_to_desc(irq);
1035
1036	if (!desc || !desc->kstat_irqs)
1037		return 0;
1038	return this_cpu_read(desc->kstat_irqs->cnt) - this_cpu_read(desc->kstat_irqs->ref);
1039}
1040
1041#endif
1042
1043/**
1044 * kstat_irqs_usr - Get the statistics for an interrupt from thread context
1045 * @irq:	The interrupt number
1046 *
1047 * Returns the sum of interrupt counts on all cpus since boot for @irq.
1048 *
1049 * It uses rcu to protect the access since a concurrent removal of an
1050 * interrupt descriptor is observing an rcu grace period before
1051 * delayed_free_desc()/irq_kobj_release().
1052 */
1053unsigned int kstat_irqs_usr(unsigned int irq)
1054{
1055	unsigned int sum;
1056
1057	rcu_read_lock();
1058	sum = kstat_irqs(irq);
1059	rcu_read_unlock();
1060	return sum;
1061}
1062
1063#ifdef CONFIG_LOCKDEP
1064void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
1065			     struct lock_class_key *request_class)
1066{
1067	struct irq_desc *desc = irq_to_desc(irq);
1068
1069	if (desc) {
1070		lockdep_set_class(&desc->lock, lock_class);
1071		lockdep_set_class(&desc->request_mutex, request_class);
1072	}
1073}
1074EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1075#endif