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-rw-r--r--kernel/irq/manage.c204
1 files changed, 115 insertions, 89 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 291f03664552..6458e99984c0 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -90,14 +90,14 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
90 90
91#ifdef CONFIG_GENERIC_PENDING_IRQ 91#ifdef CONFIG_GENERIC_PENDING_IRQ
92 if (desc->status & IRQ_MOVE_PCNTXT || desc->status & IRQ_DISABLED) { 92 if (desc->status & IRQ_MOVE_PCNTXT || desc->status & IRQ_DISABLED) {
93 cpumask_copy(&desc->affinity, cpumask); 93 cpumask_copy(desc->affinity, cpumask);
94 desc->chip->set_affinity(irq, cpumask); 94 desc->chip->set_affinity(irq, cpumask);
95 } else { 95 } else {
96 desc->status |= IRQ_MOVE_PENDING; 96 desc->status |= IRQ_MOVE_PENDING;
97 cpumask_copy(&desc->pending_mask, cpumask); 97 cpumask_copy(desc->pending_mask, cpumask);
98 } 98 }
99#else 99#else
100 cpumask_copy(&desc->affinity, cpumask); 100 cpumask_copy(desc->affinity, cpumask);
101 desc->chip->set_affinity(irq, cpumask); 101 desc->chip->set_affinity(irq, cpumask);
102#endif 102#endif
103 desc->status |= IRQ_AFFINITY_SET; 103 desc->status |= IRQ_AFFINITY_SET;
@@ -109,7 +109,7 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
109/* 109/*
110 * Generic version of the affinity autoselector. 110 * Generic version of the affinity autoselector.
111 */ 111 */
112int do_irq_select_affinity(unsigned int irq, struct irq_desc *desc) 112static int setup_affinity(unsigned int irq, struct irq_desc *desc)
113{ 113{
114 if (!irq_can_set_affinity(irq)) 114 if (!irq_can_set_affinity(irq))
115 return 0; 115 return 0;
@@ -119,21 +119,21 @@ int do_irq_select_affinity(unsigned int irq, struct irq_desc *desc)
119 * one of the targets is online. 119 * one of the targets is online.
120 */ 120 */
121 if (desc->status & (IRQ_AFFINITY_SET | IRQ_NO_BALANCING)) { 121 if (desc->status & (IRQ_AFFINITY_SET | IRQ_NO_BALANCING)) {
122 if (cpumask_any_and(&desc->affinity, cpu_online_mask) 122 if (cpumask_any_and(desc->affinity, cpu_online_mask)
123 < nr_cpu_ids) 123 < nr_cpu_ids)
124 goto set_affinity; 124 goto set_affinity;
125 else 125 else
126 desc->status &= ~IRQ_AFFINITY_SET; 126 desc->status &= ~IRQ_AFFINITY_SET;
127 } 127 }
128 128
129 cpumask_and(&desc->affinity, cpu_online_mask, irq_default_affinity); 129 cpumask_and(desc->affinity, cpu_online_mask, irq_default_affinity);
130set_affinity: 130set_affinity:
131 desc->chip->set_affinity(irq, &desc->affinity); 131 desc->chip->set_affinity(irq, desc->affinity);
132 132
133 return 0; 133 return 0;
134} 134}
135#else 135#else
136static inline int do_irq_select_affinity(unsigned int irq, struct irq_desc *d) 136static inline int setup_affinity(unsigned int irq, struct irq_desc *d)
137{ 137{
138 return irq_select_affinity(irq); 138 return irq_select_affinity(irq);
139} 139}
@@ -149,14 +149,14 @@ int irq_select_affinity_usr(unsigned int irq)
149 int ret; 149 int ret;
150 150
151 spin_lock_irqsave(&desc->lock, flags); 151 spin_lock_irqsave(&desc->lock, flags);
152 ret = do_irq_select_affinity(irq, desc); 152 ret = setup_affinity(irq, desc);
153 spin_unlock_irqrestore(&desc->lock, flags); 153 spin_unlock_irqrestore(&desc->lock, flags);
154 154
155 return ret; 155 return ret;
156} 156}
157 157
158#else 158#else
159static inline int do_irq_select_affinity(int irq, struct irq_desc *desc) 159static inline int setup_affinity(unsigned int irq, struct irq_desc *desc)
160{ 160{
161 return 0; 161 return 0;
162} 162}
@@ -389,9 +389,9 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
389 * allocate special interrupts that are part of the architecture. 389 * allocate special interrupts that are part of the architecture.
390 */ 390 */
391static int 391static int
392__setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new) 392__setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
393{ 393{
394 struct irqaction *old, **p; 394 struct irqaction *old, **old_ptr;
395 const char *old_name = NULL; 395 const char *old_name = NULL;
396 unsigned long flags; 396 unsigned long flags;
397 int shared = 0; 397 int shared = 0;
@@ -423,8 +423,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
423 * The following block of code has to be executed atomically 423 * The following block of code has to be executed atomically
424 */ 424 */
425 spin_lock_irqsave(&desc->lock, flags); 425 spin_lock_irqsave(&desc->lock, flags);
426 p = &desc->action; 426 old_ptr = &desc->action;
427 old = *p; 427 old = *old_ptr;
428 if (old) { 428 if (old) {
429 /* 429 /*
430 * Can't share interrupts unless both agree to and are 430 * Can't share interrupts unless both agree to and are
@@ -447,8 +447,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
447 447
448 /* add new interrupt at end of irq queue */ 448 /* add new interrupt at end of irq queue */
449 do { 449 do {
450 p = &old->next; 450 old_ptr = &old->next;
451 old = *p; 451 old = *old_ptr;
452 } while (old); 452 } while (old);
453 shared = 1; 453 shared = 1;
454 } 454 }
@@ -488,7 +488,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
488 desc->status |= IRQ_NO_BALANCING; 488 desc->status |= IRQ_NO_BALANCING;
489 489
490 /* Set default affinity mask once everything is setup */ 490 /* Set default affinity mask once everything is setup */
491 do_irq_select_affinity(irq, desc); 491 setup_affinity(irq, desc);
492 492
493 } else if ((new->flags & IRQF_TRIGGER_MASK) 493 } else if ((new->flags & IRQF_TRIGGER_MASK)
494 && (new->flags & IRQF_TRIGGER_MASK) 494 && (new->flags & IRQF_TRIGGER_MASK)
@@ -499,7 +499,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
499 (int)(new->flags & IRQF_TRIGGER_MASK)); 499 (int)(new->flags & IRQF_TRIGGER_MASK));
500 } 500 }
501 501
502 *p = new; 502 *old_ptr = new;
503 503
504 /* Reset broken irq detection when installing new handler */ 504 /* Reset broken irq detection when installing new handler */
505 desc->irq_count = 0; 505 desc->irq_count = 0;
@@ -549,90 +549,117 @@ int setup_irq(unsigned int irq, struct irqaction *act)
549 549
550 return __setup_irq(irq, desc, act); 550 return __setup_irq(irq, desc, act);
551} 551}
552EXPORT_SYMBOL_GPL(setup_irq);
552 553
553/** 554 /*
554 * free_irq - free an interrupt 555 * Internal function to unregister an irqaction - used to free
555 * @irq: Interrupt line to free 556 * regular and special interrupts that are part of the architecture.
556 * @dev_id: Device identity to free
557 *
558 * Remove an interrupt handler. The handler is removed and if the
559 * interrupt line is no longer in use by any driver it is disabled.
560 * On a shared IRQ the caller must ensure the interrupt is disabled
561 * on the card it drives before calling this function. The function
562 * does not return until any executing interrupts for this IRQ
563 * have completed.
564 *
565 * This function must not be called from interrupt context.
566 */ 557 */
567void free_irq(unsigned int irq, void *dev_id) 558static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
568{ 559{
569 struct irq_desc *desc = irq_to_desc(irq); 560 struct irq_desc *desc = irq_to_desc(irq);
570 struct irqaction **p; 561 struct irqaction *action, **action_ptr;
571 unsigned long flags; 562 unsigned long flags;
572 563
573 WARN_ON(in_interrupt()); 564 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
574 565
575 if (!desc) 566 if (!desc)
576 return; 567 return NULL;
577 568
578 spin_lock_irqsave(&desc->lock, flags); 569 spin_lock_irqsave(&desc->lock, flags);
579 p = &desc->action; 570
571 /*
572 * There can be multiple actions per IRQ descriptor, find the right
573 * one based on the dev_id:
574 */
575 action_ptr = &desc->action;
580 for (;;) { 576 for (;;) {
581 struct irqaction *action = *p; 577 action = *action_ptr;
582 578
583 if (action) { 579 if (!action) {
584 struct irqaction **pp = p; 580 WARN(1, "Trying to free already-free IRQ %d\n", irq);
581 spin_unlock_irqrestore(&desc->lock, flags);
585 582
586 p = &action->next; 583 return NULL;
587 if (action->dev_id != dev_id) 584 }
588 continue;
589 585
590 /* Found it - now remove it from the list of entries */ 586 if (action->dev_id == dev_id)
591 *pp = action->next; 587 break;
588 action_ptr = &action->next;
589 }
592 590
593 /* Currently used only by UML, might disappear one day.*/ 591 /* Found it - now remove it from the list of entries: */
592 *action_ptr = action->next;
593
594 /* Currently used only by UML, might disappear one day: */
594#ifdef CONFIG_IRQ_RELEASE_METHOD 595#ifdef CONFIG_IRQ_RELEASE_METHOD
595 if (desc->chip->release) 596 if (desc->chip->release)
596 desc->chip->release(irq, dev_id); 597 desc->chip->release(irq, dev_id);
597#endif 598#endif
598 599
599 if (!desc->action) { 600 /* If this was the last handler, shut down the IRQ line: */
600 desc->status |= IRQ_DISABLED; 601 if (!desc->action) {
601 if (desc->chip->shutdown) 602 desc->status |= IRQ_DISABLED;
602 desc->chip->shutdown(irq); 603 if (desc->chip->shutdown)
603 else 604 desc->chip->shutdown(irq);
604 desc->chip->disable(irq); 605 else
605 } 606 desc->chip->disable(irq);
606 spin_unlock_irqrestore(&desc->lock, flags); 607 }
607 unregister_handler_proc(irq, action); 608 spin_unlock_irqrestore(&desc->lock, flags);
609
610 unregister_handler_proc(irq, action);
611
612 /* Make sure it's not being used on another CPU: */
613 synchronize_irq(irq);
608 614
609 /* Make sure it's not being used on another CPU */
610 synchronize_irq(irq);
611#ifdef CONFIG_DEBUG_SHIRQ
612 /*
613 * It's a shared IRQ -- the driver ought to be
614 * prepared for it to happen even now it's
615 * being freed, so let's make sure.... We do
616 * this after actually deregistering it, to
617 * make sure that a 'real' IRQ doesn't run in
618 * parallel with our fake
619 */
620 if (action->flags & IRQF_SHARED) {
621 local_irq_save(flags);
622 action->handler(irq, dev_id);
623 local_irq_restore(flags);
624 }
625#endif
626 kfree(action);
627 return;
628 }
629 printk(KERN_ERR "Trying to free already-free IRQ %d\n", irq);
630#ifdef CONFIG_DEBUG_SHIRQ 615#ifdef CONFIG_DEBUG_SHIRQ
631 dump_stack(); 616 /*
632#endif 617 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
633 spin_unlock_irqrestore(&desc->lock, flags); 618 * event to happen even now it's being freed, so let's make sure that
634 return; 619 * is so by doing an extra call to the handler ....
620 *
621 * ( We do this after actually deregistering it, to make sure that a
622 * 'real' IRQ doesn't run in * parallel with our fake. )
623 */
624 if (action->flags & IRQF_SHARED) {
625 local_irq_save(flags);
626 action->handler(irq, dev_id);
627 local_irq_restore(flags);
635 } 628 }
629#endif
630 return action;
631}
632
633/**
634 * remove_irq - free an interrupt
635 * @irq: Interrupt line to free
636 * @act: irqaction for the interrupt
637 *
638 * Used to remove interrupts statically setup by the early boot process.
639 */
640void remove_irq(unsigned int irq, struct irqaction *act)
641{
642 __free_irq(irq, act->dev_id);
643}
644EXPORT_SYMBOL_GPL(remove_irq);
645
646/**
647 * free_irq - free an interrupt allocated with request_irq
648 * @irq: Interrupt line to free
649 * @dev_id: Device identity to free
650 *
651 * Remove an interrupt handler. The handler is removed and if the
652 * interrupt line is no longer in use by any driver it is disabled.
653 * On a shared IRQ the caller must ensure the interrupt is disabled
654 * on the card it drives before calling this function. The function
655 * does not return until any executing interrupts for this IRQ
656 * have completed.
657 *
658 * This function must not be called from interrupt context.
659 */
660void free_irq(unsigned int irq, void *dev_id)
661{
662 kfree(__free_irq(irq, dev_id));
636} 663}
637EXPORT_SYMBOL(free_irq); 664EXPORT_SYMBOL(free_irq);
638 665
@@ -679,11 +706,12 @@ int request_irq(unsigned int irq, irq_handler_t handler,
679 * the behavior is classified as "will not fix" so we need to 706 * the behavior is classified as "will not fix" so we need to
680 * start nudging drivers away from using that idiom. 707 * start nudging drivers away from using that idiom.
681 */ 708 */
682 if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) 709 if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) ==
683 == (IRQF_SHARED|IRQF_DISABLED)) 710 (IRQF_SHARED|IRQF_DISABLED)) {
684 pr_warning("IRQ %d/%s: IRQF_DISABLED is not " 711 pr_warning(
685 "guaranteed on shared IRQs\n", 712 "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
686 irq, devname); 713 irq, devname);
714 }
687 715
688#ifdef CONFIG_LOCKDEP 716#ifdef CONFIG_LOCKDEP
689 /* 717 /*
@@ -709,15 +737,13 @@ int request_irq(unsigned int irq, irq_handler_t handler,
709 if (!handler) 737 if (!handler)
710 return -EINVAL; 738 return -EINVAL;
711 739
712 action = kmalloc(sizeof(struct irqaction), GFP_ATOMIC); 740 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
713 if (!action) 741 if (!action)
714 return -ENOMEM; 742 return -ENOMEM;
715 743
716 action->handler = handler; 744 action->handler = handler;
717 action->flags = irqflags; 745 action->flags = irqflags;
718 cpus_clear(action->mask);
719 action->name = devname; 746 action->name = devname;
720 action->next = NULL;
721 action->dev_id = dev_id; 747 action->dev_id = dev_id;
722 748
723 retval = __setup_irq(irq, desc, action); 749 retval = __setup_irq(irq, desc, action);