~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/kernel/irq/irqdesc.c

Version: ~ [ linux-5.16 ] ~ [ linux-5.15.13 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.90 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.170 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.224 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.261 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.296 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.298 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

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

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp