Merge commit 'v2.6.28-rc1' into sched/urgent

9 files changed, 299 insertions, 230 deletions

diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c
index 533068cfb60..cc0f7321b8c 100644
--- a/kernel/irq/autoprobe.c
+++ b/kernel/irq/autoprobe.c
@@ -30,17 +30,16 @@ static DEFINE_MUTEX(probing_active);
 unsigned long probe_irq_on(void)
 {
 	struct irq_desc *desc;
-	unsigned long mask;
-	unsigned int i;
+	unsigned long mask = 0;
+	unsigned int status;
+	int i;
 
 	mutex_lock(&probing_active);
 	/*
 	 * something may have generated an irq long ago and we want to
 	 * flush such a longstanding irq before considering it as spurious.
 	 */
-	for (i = NR_IRQS-1; i > 0; i--) {
-		desc = irq_desc + i;
-
+	for_each_irq_desc_reverse(i, desc) {
 		spin_lock_irq(&desc->lock);
 		if (!desc->action && !(desc->status & IRQ_NOPROBE)) {
 			/*
@@ -68,9 +67,7 @@ unsigned long probe_irq_on(void)
 	 * (we must startup again here because if a longstanding irq
 	 * happened in the previous stage, it may have masked itself)
 	 */
-	for (i = NR_IRQS-1; i > 0; i--) {
-		desc = irq_desc + i;
-
+	for_each_irq_desc_reverse(i, desc) {
 		spin_lock_irq(&desc->lock);
 		if (!desc->action && !(desc->status & IRQ_NOPROBE)) {
 			desc->status |= IRQ_AUTODETECT | IRQ_WAITING;
@@ -88,11 +85,7 @@ unsigned long probe_irq_on(void)
 	/*
 	 * Now filter out any obviously spurious interrupts
 	 */
-	mask = 0;
-	for (i = 0; i < NR_IRQS; i++) {
-		unsigned int status;
-
-		desc = irq_desc + i;
+	for_each_irq_desc(i, desc) {
 		spin_lock_irq(&desc->lock);
 		status = desc->status;
 
@@ -126,14 +119,11 @@ EXPORT_SYMBOL(probe_irq_on);
  */
 unsigned int probe_irq_mask(unsigned long val)
 {
-	unsigned int mask;
+	unsigned int status, mask = 0;
+	struct irq_desc *desc;
 	int i;
 
-	mask = 0;
-	for (i = 0; i < NR_IRQS; i++) {
-		struct irq_desc *desc = irq_desc + i;
-		unsigned int status;
-
+	for_each_irq_desc(i, desc) {
 		spin_lock_irq(&desc->lock);
 		status = desc->status;
 
@@ -171,20 +161,19 @@ EXPORT_SYMBOL(probe_irq_mask);
  */
 int probe_irq_off(unsigned long val)
 {
-	int i, irq_found = 0, nr_irqs = 0;
-
-	for (i = 0; i < NR_IRQS; i++) {
-		struct irq_desc *desc = irq_desc + i;
-		unsigned int status;
+	int i, irq_found = 0, nr_of_irqs = 0;
+	struct irq_desc *desc;
+	unsigned int status;
 
+	for_each_irq_desc(i, desc) {
 		spin_lock_irq(&desc->lock);
 		status = desc->status;
 
 		if (status & IRQ_AUTODETECT) {
 			if (!(status & IRQ_WAITING)) {
-				if (!nr_irqs)
+				if (!nr_of_irqs)
 					irq_found = i;
-				nr_irqs++;
+				nr_of_irqs++;
 			}
 			desc->status = status & ~IRQ_AUTODETECT;
 			desc->chip->shutdown(i);
@@ -193,7 +182,7 @@ int probe_irq_off(unsigned long val)
 	}
 	mutex_unlock(&probing_active);
 
-	if (nr_irqs > 1)
+	if (nr_of_irqs > 1)
 		irq_found = -irq_found;
 
 	return irq_found;
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 3cd441ebf5d..10b5092e9bf 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -24,16 +24,15 @@
  */
 void dynamic_irq_init(unsigned int irq)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
 		return;
 	}
 
 	/* Ensure we don't have left over values from a previous use of this irq */
-	desc = irq_desc + irq;
 	spin_lock_irqsave(&desc->lock, flags);
 	desc->status = IRQ_DISABLED;
 	desc->chip = &no_irq_chip;
@@ -57,15 +56,14 @@ void dynamic_irq_init(unsigned int irq)
  */
 void dynamic_irq_cleanup(unsigned int irq)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		WARN(1, KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq);
 		return;
 	}
 
-	desc = irq_desc + irq;
 	spin_lock_irqsave(&desc->lock, flags);
 	if (desc->action) {
 		spin_unlock_irqrestore(&desc->lock, flags);
@@ -78,6 +76,7 @@ void dynamic_irq_cleanup(unsigned int irq)
 	desc->chip_data = NULL;
 	desc->handle_irq = handle_bad_irq;
 	desc->chip = &no_irq_chip;
+	desc->name = NULL;
 	spin_unlock_irqrestore(&desc->lock, flags);
 }
 
@@ -89,10 +88,10 @@ void dynamic_irq_cleanup(unsigned int irq)
  */
 int set_irq_chip(unsigned int irq, struct irq_chip *chip)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq);
 		return -EINVAL;
 	}
@@ -100,7 +99,6 @@ int set_irq_chip(unsigned int irq, struct irq_chip *chip)
 	if (!chip)
 		chip = &no_irq_chip;
 
-	desc = irq_desc + irq;
 	spin_lock_irqsave(&desc->lock, flags);
 	irq_chip_set_defaults(chip);
 	desc->chip = chip;
@@ -111,27 +109,27 @@ int set_irq_chip(unsigned int irq, struct irq_chip *chip)
 EXPORT_SYMBOL(set_irq_chip);
 
 /**
- *	set_irq_type - set the irq type for an irq
+ *	set_irq_type - set the irq trigger type for an irq
  *	@irq:	irq number
- *	@type:	interrupt type - see include/linux/interrupt.h
+ *	@type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
  */
 int set_irq_type(unsigned int irq, unsigned int type)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 	int ret = -ENXIO;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
 		return -ENODEV;
 	}
 
-	desc = irq_desc + irq;
-	if (desc->chip->set_type) {
-		spin_lock_irqsave(&desc->lock, flags);
-		ret = desc->chip->set_type(irq, type);
-		spin_unlock_irqrestore(&desc->lock, flags);
-	}
+	if (type == IRQ_TYPE_NONE)
+		return 0;
+
+	spin_lock_irqsave(&desc->lock, flags);
+	ret = __irq_set_trigger(desc, irq, type);
+	spin_unlock_irqrestore(&desc->lock, flags);
 	return ret;
 }
 EXPORT_SYMBOL(set_irq_type);
@@ -145,16 +143,15 @@ EXPORT_SYMBOL(set_irq_type);
  */
 int set_irq_data(unsigned int irq, void *data)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		printk(KERN_ERR
 		       "Trying to install controller data for IRQ%d\n", irq);
 		return -EINVAL;
 	}
 
-	desc = irq_desc + irq;
 	spin_lock_irqsave(&desc->lock, flags);
 	desc->handler_data = data;
 	spin_unlock_irqrestore(&desc->lock, flags);
@@ -171,15 +168,15 @@ EXPORT_SYMBOL(set_irq_data);
  */
 int set_irq_msi(unsigned int irq, struct msi_desc *entry)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		printk(KERN_ERR
 		       "Trying to install msi data for IRQ%d\n", irq);
 		return -EINVAL;
 	}
-	desc = irq_desc + irq;
+
 	spin_lock_irqsave(&desc->lock, flags);
 	desc->msi_desc = entry;
 	if (entry)
@@ -197,10 +194,16 @@ int set_irq_msi(unsigned int irq, struct msi_desc *entry)
  */
 int set_irq_chip_data(unsigned int irq, void *data)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS || !desc->chip) {
+	if (!desc) {
+		printk(KERN_ERR
+		       "Trying to install chip data for IRQ%d\n", irq);
+		return -EINVAL;
+	}
+
+	if (!desc->chip) {
 		printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq);
 		return -EINVAL;
 	}
@@ -218,7 +221,7 @@ EXPORT_SYMBOL(set_irq_chip_data);
  */
 static void default_enable(unsigned int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 
 	desc->chip->unmask(irq);
 	desc->status &= ~IRQ_MASKED;
@@ -236,8 +239,9 @@ static void default_disable(unsigned int irq)
  */
 static unsigned int default_startup(unsigned int irq)
 {
-	irq_desc[irq].chip->enable(irq);
+	struct irq_desc *desc = irq_to_desc(irq);
 
+	desc->chip->enable(irq);
 	return 0;
 }
 
@@ -246,7 +250,7 @@ static unsigned int default_startup(unsigned int irq)
  */
 static void default_shutdown(unsigned int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 
 	desc->chip->mask(irq);
 	desc->status |= IRQ_MASKED;
@@ -305,14 +309,13 @@ handle_simple_irq(unsigned int irq, struct irq_desc *desc)
 {
 	struct irqaction *action;
 	irqreturn_t action_ret;
-	const unsigned int cpu = smp_processor_id();
 
 	spin_lock(&desc->lock);
 
 	if (unlikely(desc->status & IRQ_INPROGRESS))
 		goto out_unlock;
 	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
-	kstat_cpu(cpu).irqs[irq]++;
+	kstat_incr_irqs_this_cpu(irq, desc);
 
 	action = desc->action;
 	if (unlikely(!action || (desc->status & IRQ_DISABLED)))
@@ -344,7 +347,6 @@ out_unlock:
 void
 handle_level_irq(unsigned int irq, struct irq_desc *desc)
 {
-	unsigned int cpu = smp_processor_id();
 	struct irqaction *action;
 	irqreturn_t action_ret;
 
@@ -354,7 +356,7 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
 	if (unlikely(desc->status & IRQ_INPROGRESS))
 		goto out_unlock;
 	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
-	kstat_cpu(cpu).irqs[irq]++;
+	kstat_incr_irqs_this_cpu(irq, desc);
 
 	/*
 	 * If its disabled or no action available
@@ -392,7 +394,6 @@ out_unlock:
 void
 handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
 {
-	unsigned int cpu = smp_processor_id();
 	struct irqaction *action;
 	irqreturn_t action_ret;
 
@@ -402,7 +403,7 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
 		goto out;
 
 	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
-	kstat_cpu(cpu).irqs[irq]++;
+	kstat_incr_irqs_this_cpu(irq, desc);
 
 	/*
 	 * If its disabled or no action available
@@ -451,8 +452,6 @@ out:
 void
 handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 {
-	const unsigned int cpu = smp_processor_id();
-
 	spin_lock(&desc->lock);
 
 	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
@@ -468,8 +467,7 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 		mask_ack_irq(desc, irq);
 		goto out_unlock;
 	}
-
-	kstat_cpu(cpu).irqs[irq]++;
+	kstat_incr_irqs_this_cpu(irq, desc);
 
 	/* Start handling the irq */
 	desc->chip->ack(irq);
@@ -524,7 +522,7 @@ handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
 {
 	irqreturn_t action_ret;
 
-	kstat_this_cpu.irqs[irq]++;
+	kstat_incr_irqs_this_cpu(irq, desc);
 
 	if (desc->chip->ack)
 		desc->chip->ack(irq);
@@ -541,17 +539,15 @@ void
 __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		  const char *name)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		printk(KERN_ERR
 		       "Trying to install type control for IRQ%d\n", irq);
 		return;
 	}
 
-	desc = irq_desc + irq;
-
 	if (!handle)
 		handle = handle_bad_irq;
 	else if (desc->chip == &no_irq_chip) {
@@ -583,7 +579,7 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		desc->status &= ~IRQ_DISABLED;
 		desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE;
 		desc->depth = 0;
-		desc->chip->unmask(irq);
+		desc->chip->startup(irq);
 	}
 	spin_unlock_irqrestore(&desc->lock, flags);
 }
@@ -606,17 +602,14 @@ set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
 
 void __init set_irq_noprobe(unsigned int irq)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq);
-
 		return;
 	}
 
-	desc = irq_desc + irq;
-
 	spin_lock_irqsave(&desc->lock, flags);
 	desc->status |= IRQ_NOPROBE;
 	spin_unlock_irqrestore(&desc->lock, flags);
@@ -624,17 +617,14 @@ void __init set_irq_noprobe(unsigned int irq)
 
 void __init set_irq_probe(unsigned int irq)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS) {
+	if (!desc) {
 		printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq);
-
 		return;
 	}
 
-	desc = irq_desc + irq;
-
 	spin_lock_irqsave(&desc->lock, flags);
 	desc->status &= ~IRQ_NOPROBE;
 	spin_unlock_irqrestore(&desc->lock, flags);
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 5fa6198e913..c815b42d0f5 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -25,11 +25,10 @@
  *
  * Handles spurious and unhandled IRQ's. It also prints a debugmessage.
  */
-void
-handle_bad_irq(unsigned int irq, struct irq_desc *desc)
+void handle_bad_irq(unsigned int irq, struct irq_desc *desc)
 {
 	print_irq_desc(irq, desc);
-	kstat_this_cpu.irqs[irq]++;
+	kstat_incr_irqs_this_cpu(irq, desc);
 	ack_bad_irq(irq);
 }
 
@@ -47,6 +46,9 @@ handle_bad_irq(unsigned int irq, struct irq_desc *desc)
  *
  * Controller mappings for all interrupt sources:
  */
+int nr_irqs = NR_IRQS;
+EXPORT_SYMBOL_GPL(nr_irqs);
+
 struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
 	[0 ... NR_IRQS-1] = {
 		.status = IRQ_DISABLED,
@@ -66,7 +68,9 @@ struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
  */
 static void ack_bad(unsigned int irq)
 {
-	print_irq_desc(irq, irq_desc + irq);
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	print_irq_desc(irq, desc);
 	ack_bad_irq(irq);
 }
 
@@ -131,8 +135,6 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
 	irqreturn_t ret, retval = IRQ_NONE;
 	unsigned int status = 0;
 
-	handle_dynamic_tick(action);
-
 	if (!(action->flags & IRQF_DISABLED))
 		local_irq_enable_in_hardirq();
 
@@ -165,11 +167,12 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
  */
 unsigned int __do_IRQ(unsigned int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	struct irqaction *action;
 	unsigned int status;
 
-	kstat_this_cpu.irqs[irq]++;
+	kstat_incr_irqs_this_cpu(irq, desc);
+
 	if (CHECK_IRQ_PER_CPU(desc->status)) {
 		irqreturn_t action_ret;
 
@@ -256,8 +259,8 @@ out:
 }
 #endif
 
-#ifdef CONFIG_TRACE_IRQFLAGS
 
+#ifdef CONFIG_TRACE_IRQFLAGS
 /*
  * lockdep: we want to handle all irq_desc locks as a single lock-class:
  */
@@ -265,10 +268,10 @@ static struct lock_class_key irq_desc_lock_class;
 
 void early_init_irq_lock_class(void)
 {
+	struct irq_desc *desc;
 	int i;
 
-	for (i = 0; i < NR_IRQS; i++)
-		lockdep_set_class(&irq_desc[i].lock, &irq_desc_lock_class);
+	for_each_irq_desc(i, desc)
+		lockdep_set_class(&desc->lock, &irq_desc_lock_class);
 }
-
 #endif
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 08a849a2244..c9767e64198 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -10,12 +10,15 @@ extern void irq_chip_set_defaults(struct irq_chip *chip);
 /* Set default handler: */
 extern void compat_irq_chip_set_default_handler(struct irq_desc *desc);
 
+extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
+		unsigned long flags);
+
 #ifdef CONFIG_PROC_FS
-extern void register_irq_proc(unsigned int irq);
+extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
 #else
-static inline void register_irq_proc(unsigned int irq) { }
+static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
 static inline void register_handler_proc(unsigned int irq,
 					 struct irqaction *action) { }
 static inline void unregister_handler_proc(unsigned int irq,
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 60c49e32439..c498a1b8c62 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -31,10 +31,10 @@ cpumask_t irq_default_affinity = CPU_MASK_ALL;
  */
 void synchronize_irq(unsigned int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned int status;
 
-	if (irq >= NR_IRQS)
+	if (!desc)
 		return;
 
 	do {
@@ -64,7 +64,7 @@ EXPORT_SYMBOL(synchronize_irq);
  */
 int irq_can_set_affinity(unsigned int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 
 	if (CHECK_IRQ_PER_CPU(desc->status) || !desc->chip ||
 	    !desc->chip->set_affinity)
@@ -81,18 +81,17 @@ int irq_can_set_affinity(unsigned int irq)
  */
 int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 
 	if (!desc->chip->set_affinity)
 		return -EINVAL;
 
-	set_balance_irq_affinity(irq, cpumask);
-
 #ifdef CONFIG_GENERIC_PENDING_IRQ
-	if (desc->status & IRQ_MOVE_PCNTXT) {
+	if (desc->status & IRQ_MOVE_PCNTXT || desc->status & IRQ_DISABLED) {
 		unsigned long flags;
 
 		spin_lock_irqsave(&desc->lock, flags);
+		desc->affinity = cpumask;
 		desc->chip->set_affinity(irq, cpumask);
 		spin_unlock_irqrestore(&desc->lock, flags);
 	} else
@@ -111,16 +110,17 @@ int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
 int irq_select_affinity(unsigned int irq)
 {
 	cpumask_t mask;
+	struct irq_desc *desc;
 
 	if (!irq_can_set_affinity(irq))
 		return 0;
 
 	cpus_and(mask, cpu_online_map, irq_default_affinity);
 
-	irq_desc[irq].affinity = mask;
-	irq_desc[irq].chip->set_affinity(irq, mask);
+	desc = irq_to_desc(irq);
+	desc->affinity = mask;
+	desc->chip->set_affinity(irq, mask);
 
-	set_balance_irq_affinity(irq, mask);
 	return 0;
 }
 #endif
@@ -140,10 +140,10 @@ int irq_select_affinity(unsigned int irq)
  */
 void disable_irq_nosync(unsigned int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS)
+	if (!desc)
 		return;
 
 	spin_lock_irqsave(&desc->lock, flags);
@@ -169,9 +169,9 @@ EXPORT_SYMBOL(disable_irq_nosync);
  */
 void disable_irq(unsigned int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 
-	if (irq >= NR_IRQS)
+	if (!desc)
 		return;
 
 	disable_irq_nosync(irq);
@@ -211,10 +211,10 @@ static void __enable_irq(struct irq_desc *desc, unsigned int irq)
  */
 void enable_irq(unsigned int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
-	if (irq >= NR_IRQS)
+	if (!desc)
 		return;
 
 	spin_lock_irqsave(&desc->lock, flags);
@@ -223,9 +223,9 @@ void enable_irq(unsigned int irq)
 }
 EXPORT_SYMBOL(enable_irq);
 
-int set_irq_wake_real(unsigned int irq, unsigned int on)
+static int set_irq_wake_real(unsigned int irq, unsigned int on)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	int ret = -ENXIO;
 
 	if (desc->chip->set_wake)
@@ -248,7 +248,7 @@ int set_irq_wake_real(unsigned int irq, unsigned int on)
  */
 int set_irq_wake(unsigned int irq, unsigned int on)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 	int ret = 0;
 
@@ -288,12 +288,16 @@ EXPORT_SYMBOL(set_irq_wake);
  */
 int can_request_irq(unsigned int irq, unsigned long irqflags)
 {
+	struct irq_desc *desc = irq_to_desc(irq);
 	struct irqaction *action;
 
-	if (irq >= NR_IRQS || irq_desc[irq].status & IRQ_NOREQUEST)
+	if (!desc)
+		return 0;
+
+	if (desc->status & IRQ_NOREQUEST)
 		return 0;
 
-	action = irq_desc[irq].action;
+	action = desc->action;
 	if (action)
 		if (irqflags & action->flags & IRQF_SHARED)
 			action = NULL;
@@ -312,10 +316,11 @@ void compat_irq_chip_set_default_handler(struct irq_desc *desc)
 		desc->handle_irq = NULL;
 }
 
-static int __irq_set_trigger(struct irq_chip *chip, unsigned int irq,
+int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
 		unsigned long flags)
 {
 	int ret;
+	struct irq_chip *chip = desc->chip;
 
 	if (!chip || !chip->set_type) {
 		/*
@@ -333,6 +338,11 @@ static int __irq_set_trigger(struct irq_chip *chip, unsigned int irq,
 		pr_err("setting trigger mode %d for irq %u failed (%pF)\n",
 				(int)(flags & IRQF_TRIGGER_MASK),
 				irq, chip->set_type);
+	else {
+		/* note that IRQF_TRIGGER_MASK == IRQ_TYPE_SENSE_MASK */
+		desc->status &= ~IRQ_TYPE_SENSE_MASK;
+		desc->status |= flags & IRQ_TYPE_SENSE_MASK;
+	}
 
 	return ret;
 }
@@ -341,16 +351,16 @@ static int __irq_set_trigger(struct irq_chip *chip, unsigned int irq,
  * Internal function to register an irqaction - typically used to
  * allocate special interrupts that are part of the architecture.
  */
-int setup_irq(unsigned int irq, struct irqaction *new)
+static int
+__setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
 {
-	struct irq_desc *desc = irq_desc + irq;
 	struct irqaction *old, **p;
 	const char *old_name = NULL;
 	unsigned long flags;
 	int shared = 0;
 	int ret;
 
-	if (irq >= NR_IRQS)
+	if (!desc)
 		return -EINVAL;
 
 	if (desc->chip == &no_irq_chip)
@@ -411,7 +421,7 @@ int setup_irq(unsigned int irq, struct irqaction *new)
 
 		/* Setup the type (level, edge polarity) if configured: */
 		if (new->flags & IRQF_TRIGGER_MASK) {
-			ret = __irq_set_trigger(desc->chip, irq, new->flags);
+			ret = __irq_set_trigger(desc, irq, new->flags);
 
 			if (ret) {
 				spin_unlock_irqrestore(&desc->lock, flags);
@@ -430,16 +440,21 @@ int setup_irq(unsigned int irq, struct irqaction *new)
 		if (!(desc->status & IRQ_NOAUTOEN)) {
 			desc->depth = 0;
 			desc->status &= ~IRQ_DISABLED;
-			if (desc->chip->startup)
-				desc->chip->startup(irq);
-			else
-				desc->chip->enable(irq);
+			desc->chip->startup(irq);
 		} else
 			/* Undo nested disables: */
 			desc->depth = 1;
 
 		/* Set default affinity mask once everything is setup */
 		irq_select_affinity(irq);
+
+	} else if ((new->flags & IRQF_TRIGGER_MASK)
+			&& (new->flags & IRQF_TRIGGER_MASK)
+				!= (desc->status & IRQ_TYPE_SENSE_MASK)) {
+		/* hope the handler works with the actual trigger mode... */
+		pr_warning("IRQ %d uses trigger mode %d; requested %d\n",
+				irq, (int)(desc->status & IRQ_TYPE_SENSE_MASK),
+				(int)(new->flags & IRQF_TRIGGER_MASK));
 	}
 
 	*p = new;
@@ -464,7 +479,7 @@ int setup_irq(unsigned int irq, struct irqaction *new)
 	spin_unlock_irqrestore(&desc->lock, flags);
 
 	new->irq = irq;
-	register_irq_proc(irq);
+	register_irq_proc(irq, desc);
 	new->dir = NULL;
 	register_handler_proc(irq, new);
 
@@ -484,6 +499,20 @@ mismatch:
 }
 
 /**
+ *	setup_irq - setup an interrupt
+ *	@irq: Interrupt line to setup
+ *	@act: irqaction for the interrupt
+ *
+ * Used to statically setup interrupts in the early boot process.
+ */
+int setup_irq(unsigned int irq, struct irqaction *act)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	return __setup_irq(irq, desc, act);
+}
+
+/**
  *	free_irq - free an interrupt
  *	@irq: Interrupt line to free
  *	@dev_id: Device identity to free
@@ -499,15 +528,15 @@ mismatch:
  */
 void free_irq(unsigned int irq, void *dev_id)
 {
-	struct irq_desc *desc;
+	struct irq_desc *desc = irq_to_desc(irq);
 	struct irqaction **p;
 	unsigned long flags;
 
 	WARN_ON(in_interrupt());
-	if (irq >= NR_IRQS)
+
+	if (!desc)
 		return;
 
-	desc = irq_desc + irq;
 	spin_lock_irqsave(&desc->lock, flags);
 	p = &desc->action;
 	for (;;) {
@@ -596,12 +625,14 @@ EXPORT_SYMBOL(free_irq);
  *	IRQF_SHARED		Interrupt is shared
  *	IRQF_DISABLED	Disable local interrupts while processing
  *	IRQF_SAMPLE_RANDOM	The interrupt can be used for entropy
+ *	IRQF_TRIGGER_*		Specify active edge(s) or level
  *
  */
 int request_irq(unsigned int irq, irq_handler_t handler,
 		unsigned long irqflags, const char *devname, void *dev_id)
 {
 	struct irqaction *action;
+	struct irq_desc *desc;
 	int retval;
 
 #ifdef CONFIG_LOCKDEP
@@ -618,9 +649,12 @@ int request_irq(unsigned int irq, irq_handler_t handler,
 	 */
 	if ((irqflags & IRQF_SHARED) && !dev_id)
 		return -EINVAL;
-	if (irq >= NR_IRQS)
+
+	desc = irq_to_desc(irq);
+	if (!desc)
 		return -EINVAL;
-	if (irq_desc[irq].status & IRQ_NOREQUEST)
+
+	if (desc->status & IRQ_NOREQUEST)
 		return -EINVAL;
 	if (!handler)
 		return -EINVAL;
@@ -636,26 +670,29 @@ int request_irq(unsigned int irq, irq_handler_t handler,
 	action->next = NULL;
 	action->dev_id = dev_id;
 
+	retval = __setup_irq(irq, desc, action);
+	if (retval)
+		kfree(action);
+
 #ifdef CONFIG_DEBUG_SHIRQ
 	if (irqflags & IRQF_SHARED) {
 		/*
 		 * It's a shared IRQ -- the driver ought to be prepared for it
 		 * to happen immediately, so let's make sure....
-		 * We do this before actually registering it, to make sure that
-		 * a 'real' IRQ doesn't run in parallel with our fake
+		 * We disable the irq to make sure that a 'real' IRQ doesn't
+		 * run in parallel with our fake.
 		 */
 		unsigned long flags;
 
+		disable_irq(irq);
 		local_irq_save(flags);
+
 		handler(irq, dev_id);
+
 		local_irq_restore(flags);
+		enable_irq(irq);
 	}
 #endif
-
-	retval = setup_irq(irq, action);
-	if (retval)
-		kfree(action);
-
 	return retval;
 }
 EXPORT_SYMBOL(request_irq);
diff --git a/kernel/irq/migration.c b/kernel/irq/migration.c
index 77b7acc875c..90b920d3f52 100644
--- a/kernel/irq/migration.c
+++ b/kernel/irq/migration.c
@@ -3,18 +3,18 @@
 
 void set_pending_irq(unsigned int irq, cpumask_t mask)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
 
 	spin_lock_irqsave(&desc->lock, flags);
 	desc->status |= IRQ_MOVE_PENDING;
-	irq_desc[irq].pending_mask = mask;
+	desc->pending_mask = mask;
 	spin_unlock_irqrestore(&desc->lock, flags);
 }
 
 void move_masked_irq(int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	cpumask_t tmp;
 
 	if (likely(!(desc->status & IRQ_MOVE_PENDING)))
@@ -30,7 +30,7 @@ void move_masked_irq(int irq)
 
 	desc->status &= ~IRQ_MOVE_PENDING;
 
-	if (unlikely(cpus_empty(irq_desc[irq].pending_mask)))
+	if (unlikely(cpus_empty(desc->pending_mask)))
 		return;
 
 	if (!desc->chip->set_affinity)
@@ -38,7 +38,7 @@ void move_masked_irq(int irq)
 
 	assert_spin_locked(&desc->lock);
 
-	cpus_and(tmp, irq_desc[irq].pending_mask, cpu_online_map);
+	cpus_and(tmp, desc->pending_mask, cpu_online_map);
 
 	/*
 	 * If there was a valid mask to work with, please
@@ -55,12 +55,12 @@ void move_masked_irq(int irq)
 	if (likely(!cpus_empty(tmp))) {
 		desc->chip->set_affinity(irq,tmp);
 	}
-	cpus_clear(irq_desc[irq].pending_mask);
+	cpus_clear(desc->pending_mask);
 }
 
 void move_native_irq(int irq)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 
 	if (likely(!(desc->status & IRQ_MOVE_PENDING)))
 		return;
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index a09dd29c2fd..fac014a81b2 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -19,7 +19,7 @@ static struct proc_dir_entry *root_irq_dir;
 
 static int irq_affinity_proc_show(struct seq_file *m, void *v)
 {
-	struct irq_desc *desc = irq_desc + (long)m->private;
+	struct irq_desc *desc = irq_to_desc((long)m->private);
 	cpumask_t *mask = &desc->affinity;
 
 #ifdef CONFIG_GENERIC_PENDING_IRQ
@@ -43,7 +43,7 @@ static ssize_t irq_affinity_proc_write(struct file *file,
 	cpumask_t new_value;
 	int err;
 
-	if (!irq_desc[irq].chip->set_affinity || no_irq_affinity ||
+	if (!irq_to_desc(irq)->chip->set_affinity || no_irq_affinity ||
 	    irq_balancing_disabled(irq))
 		return -EIO;
 
@@ -132,20 +132,20 @@ static const struct file_operations default_affinity_proc_fops = {
 static int irq_spurious_read(char *page, char **start, off_t off,
 				  int count, int *eof, void *data)
 {
-	struct irq_desc *d = &irq_desc[(long) data];
+	struct irq_desc *desc = irq_to_desc((long) data);
 	return sprintf(page, "count %u\n"
 			     "unhandled %u\n"
 			     "last_unhandled %u ms\n",
-			d->irq_count,
-			d->irqs_unhandled,
-			jiffies_to_msecs(d->last_unhandled));
+			desc->irq_count,
+			desc->irqs_unhandled,
+			jiffies_to_msecs(desc->last_unhandled));
 }
 
 #define MAX_NAMELEN 128
 
 static int name_unique(unsigned int irq, struct irqaction *new_action)
 {
-	struct irq_desc *desc = irq_desc + irq;
+	struct irq_desc *desc = irq_to_desc(irq);
 	struct irqaction *action;
 	unsigned long flags;
 	int ret = 1;
@@ -165,8 +165,9 @@ static int name_unique(unsigned int irq, struct irqaction *new_action)
 void register_handler_proc(unsigned int irq, struct irqaction *action)
 {
 	char name [MAX_NAMELEN];
+	struct irq_desc *desc = irq_to_desc(irq);
 
-	if (!irq_desc[irq].dir || action->dir || !action->name ||
+	if (!desc->dir || action->dir || !action->name ||
 					!name_unique(irq, action))
 		return;
 
@@ -174,36 +175,34 @@ void register_handler_proc(unsigned int irq, struct irqaction *action)
 	snprintf(name, MAX_NAMELEN, "%s", action->name);
 
 	/* create /proc/irq/1234/handler/ */
-	action->dir = proc_mkdir(name, irq_desc[irq].dir);
+	action->dir = proc_mkdir(name, desc->dir);
 }
 
 #undef MAX_NAMELEN
 
 #define MAX_NAMELEN 10
 
-void register_irq_proc(unsigned int irq)
+void register_irq_proc(unsigned int irq, struct irq_desc *desc)
 {
 	char name [MAX_NAMELEN];
 	struct proc_dir_entry *entry;
 
-	if (!root_irq_dir ||
-		(irq_desc[irq].chip == &no_irq_chip) ||
-			irq_desc[irq].dir)
+	if (!root_irq_dir || (desc->chip == &no_irq_chip) || desc->dir)
 		return;
 
 	memset(name, 0, MAX_NAMELEN);
 	sprintf(name, "%d", irq);
 
 	/* create /proc/irq/1234 */
-	irq_desc[irq].dir = proc_mkdir(name, root_irq_dir);
+	desc->dir = proc_mkdir(name, root_irq_dir);
 
 #ifdef CONFIG_SMP
 	/* create /proc/irq/<irq>/smp_affinity */
-	proc_create_data("smp_affinity", 0600, irq_desc[irq].dir,
+	proc_create_data("smp_affinity", 0600, desc->dir,
 			 &irq_affinity_proc_fops, (void *)(long)irq);
 #endif
 
-	entry = create_proc_entry("spurious", 0444, irq_desc[irq].dir);
+	entry = create_proc_entry("spurious", 0444, desc->dir);
 	if (entry) {
 		entry->data = (void *)(long)irq;
 		entry->read_proc = irq_spurious_read;
@@ -214,8 +213,11 @@ void register_irq_proc(unsigned int irq)
 
 void unregister_handler_proc(unsigned int irq, struct irqaction *action)
 {
-	if (action->dir)
-		remove_proc_entry(action->dir->name, irq_desc[irq].dir);
+	if (action->dir) {
+		struct irq_desc *desc = irq_to_desc(irq);
+
+		remove_proc_entry(action->dir->name, desc->dir);
+	}
 }
 
 void register_default_affinity_proc(void)
@@ -228,7 +230,8 @@ void register_default_affinity_proc(void)
 
 void init_irq_proc(void)
 {
-	int i;
+	unsigned int irq;
+	struct irq_desc *desc;
 
 	/* create /proc/irq */
 	root_irq_dir = proc_mkdir("irq", NULL);
@@ -240,7 +243,7 @@ void init_irq_proc(void)
 	/*
 	 * Create entries for all existing IRQs.
 	 */
-	for (i = 0; i < NR_IRQS; i++)
-		register_irq_proc(i);
+	for_each_irq_desc(irq, desc)
+		register_irq_proc(irq, desc);
 }
 
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index a8046791ba2..89c7117acf2 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -33,10 +33,10 @@ static void resend_irqs(unsigned long arg)
 	struct irq_desc *desc;
 	int irq;
 
-	while (!bitmap_empty(irqs_resend, NR_IRQS)) {
-		irq = find_first_bit(irqs_resend, NR_IRQS);
+	while (!bitmap_empty(irqs_resend, nr_irqs)) {
+		irq = find_first_bit(irqs_resend, nr_irqs);
 		clear_bit(irq, irqs_resend);
-		desc = irq_desc + irq;
+		desc = irq_to_desc(irq);
 		local_irq_disable();
 		desc->handle_irq(irq, desc);
 		local_irq_enable();
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index c66d3f10e85..dd364c11e56 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -12,83 +12,122 @@
 #include <linux/kallsyms.h>
 #include <linux/interrupt.h>
 #include <linux/moduleparam.h>
+#include <linux/timer.h>
 
 static int irqfixup __read_mostly;
 
+#define POLL_SPURIOUS_IRQ_INTERVAL (HZ/10)
+static void poll_spurious_irqs(unsigned long dummy);
+static DEFINE_TIMER(poll_spurious_irq_timer, poll_spurious_irqs, 0, 0);
+
 /*
  * Recovery handler for misrouted interrupts.
  */
-static int misrouted_irq(int irq)
+static int try_one_irq(int irq, struct irq_desc *desc)
 {
-	int i;
-	int ok = 0;
-	int work = 0;	/* Did we do work for a real IRQ */
-
-	for (i = 1; i < NR_IRQS; i++) {
-		struct irq_desc *desc = irq_desc + i;
-		struct irqaction *action;
-
-		if (i == irq)	/* Already tried */
-			continue;
+	struct irqaction *action;
+	int ok = 0, work = 0;
 
-		spin_lock(&desc->lock);
-		/* Already running on another processor */
-		if (desc->status & IRQ_INPROGRESS) {
-			/*
-			 * Already running: If it is shared get the other
-			 * CPU to go looking for our mystery interrupt too
-			 */
-			if (desc->action && (desc->action->flags & IRQF_SHARED))
-				desc->status |= IRQ_PENDING;
-			spin_unlock(&desc->lock);
-			continue;
-		}
-		/* Honour the normal IRQ locking */
-		desc->status |= IRQ_INPROGRESS;
-		action = desc->action;
+	spin_lock(&desc->lock);
+	/* Already running on another processor */
+	if (desc->status & IRQ_INPROGRESS) {
+		/*
+		 * Already running: If it is shared get the other
+		 * CPU to go looking for our mystery interrupt too
+		 */
+		if (desc->action && (desc->action->flags & IRQF_SHARED))
+			desc->status |= IRQ_PENDING;
 		spin_unlock(&desc->lock);
+		return ok;
+	}
+	/* Honour the normal IRQ locking */
+	desc->status |= IRQ_INPROGRESS;
+	action = desc->action;
+	spin_unlock(&desc->lock);
 
-		while (action) {
-			/* Only shared IRQ handlers are safe to call */
-			if (action->flags & IRQF_SHARED) {
-				if (action->handler(i, action->dev_id) ==
-						IRQ_HANDLED)
-					ok = 1;
-			}
-			action = action->next;
+	while (action) {
+		/* Only shared IRQ handlers are safe to call */
+		if (action->flags & IRQF_SHARED) {
+			if (action->handler(irq, action->dev_id) ==
+				IRQ_HANDLED)
+				ok = 1;
 		}
-		local_irq_disable();
-		/* Now clean up the flags */
-		spin_lock(&desc->lock);
-		action = desc->action;
+		action = action->next;
+	}
+	local_irq_disable();
+	/* Now clean up the flags */
+	spin_lock(&desc->lock);
+	action = desc->action;
 
+	/*
+	 * While we were looking for a fixup someone queued a real
+	 * IRQ clashing with our walk:
+	 */
+	while ((desc->status & IRQ_PENDING) && action) {
 		/*
-		 * While we were looking for a fixup someone queued a real
-		 * IRQ clashing with our walk:
-		 */
-		while ((desc->status & IRQ_PENDING) && action) {
-			/*
-			 * Perform real IRQ processing for the IRQ we deferred
-			 */
-			work = 1;
-			spin_unlock(&desc->lock);
-			handle_IRQ_event(i, action);
-			spin_lock(&desc->lock);
-			desc->status &= ~IRQ_PENDING;
-		}
-		desc->status &= ~IRQ_INPROGRESS;
-		/*
-		 * If we did actual work for the real IRQ line we must let the
-		 * IRQ controller clean up too
+		 * Perform real IRQ processing for the IRQ we deferred
 		 */
-		if (work && desc->chip && desc->chip->end)
-			desc->chip->end(i);
+		work = 1;
 		spin_unlock(&desc->lock);
+		handle_IRQ_event(irq, action);
+		spin_lock(&desc->lock);
+		desc->status &= ~IRQ_PENDING;
+	}
+	desc->status &= ~IRQ_INPROGRESS;
+	/*
+	 * If we did actual work for the real IRQ line we must let the
+	 * IRQ controller clean up too
+	 */
+	if (work && desc->chip && desc->chip->end)
+		desc->chip->end(irq);
+	spin_unlock(&desc->lock);
+
+	return ok;
+}
+
+static int misrouted_irq(int irq)
+{
+	struct irq_desc *desc;
+	int i, ok = 0;
+
+	for_each_irq_desc(i, desc) {
+		if (!i)
+			 continue;
+
+		if (i == irq)	/* Already tried */
+			continue;
+
+		if (try_one_irq(i, desc))
+			ok = 1;
 	}
 	/* So the caller can adjust the irq error counts */
 	return ok;
 }
 
+static void poll_spurious_irqs(unsigned long dummy)
+{
+	struct irq_desc *desc;
+	int i;
+
+	for_each_irq_desc(i, desc) {
+		unsigned int status;
+
+		if (!i)
+			 continue;
+
+		/* Racy but it doesn't matter */
+		status = desc->status;
+		barrier();
+		if (!(status & IRQ_SPURIOUS_DISABLED))
+			continue;
+
+		try_one_irq(i, desc);
+	}
+
+	mod_timer(&poll_spurious_irq_timer,
+		  jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
+}
+
 /*
  * If 99,900 of the previous 100,000 interrupts have not been handled
  * then assume that the IRQ is stuck in some manner. Drop a diagnostic
@@ -137,7 +176,9 @@ report_bad_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret)
 	}
 }
 
-static inline int try_misrouted_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret)
+static inline int
+try_misrouted_irq(unsigned int irq, struct irq_desc *desc,
+		  irqreturn_t action_ret)
 {
 	struct irqaction *action;
 
@@ -212,6 +253,9 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc,
 		desc->status |= IRQ_DISABLED | IRQ_SPURIOUS_DISABLED;
 		desc->depth++;
 		desc->chip->disable(irq);
+
+		mod_timer(&poll_spurious_irq_timer,
+			  jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
 	}
 	desc->irqs_unhandled = 0;
 }
@@ -241,7 +285,7 @@ static int __init irqfixup_setup(char *str)
 
 __setup("irqfixup", irqfixup_setup);
 module_param(irqfixup, int, 0644);
-MODULE_PARM_DESC("irqfixup", "0: No fixup, 1: irqfixup mode 2: irqpoll mode");
+MODULE_PARM_DESC("irqfixup", "0: No fixup, 1: irqfixup mode, 2: irqpoll mode");
 
 static int __init irqpoll_setup(char *str)
 {