Commit a3016b26 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

genirq: Use irq_resolve_mapping() to implement __handle_domain_irq() and co 



In order to start reaping the benefits of irq_resolve_mapping(),
start using it in __handle_domain_irq() and handle_domain_nmi().

This involves splitting generic_handle_irq() to be able to directly
provide the irq_desc.

Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent d22558dd

include/linux/irqdesc.h

+1 −0
Original line number Diff line number Diff line
@@ -158,6 +158,7 @@ static inline void generic_handle_irq_desc(struct irq_desc *desc) 
	desc->handle_irq(desc);

}



int handle_irq_desc(struct irq_desc *desc);

int generic_handle_irq(unsigned int irq);



#ifdef CONFIG_HANDLE_DOMAIN_IRQ

kernel/irq/irqdesc.c

+35 −25
Original line number Diff line number Diff line
@@ -632,14 +632,8 @@ void irq_init_desc(unsigned int irq) 


#endif /* !CONFIG_SPARSE_IRQ */



/**

 * generic_handle_irq - Invoke the handler for a particular irq

 * @irq:	The irq number to handle

 *

 */

int generic_handle_irq(unsigned int irq)

int handle_irq_desc(struct irq_desc *desc)

{

	struct irq_desc *desc = irq_to_desc(irq);

	struct irq_data *data;



	if (!desc)
@@ -652,6 +646,17 @@ int generic_handle_irq(unsigned int irq) 
	generic_handle_irq_desc(desc);

	return 0;

}

EXPORT_SYMBOL_GPL(handle_irq_desc);



/**

 * generic_handle_irq - Invoke the handler for a particular irq

 * @irq:	The irq number to handle

 *

 */

int generic_handle_irq(unsigned int irq)

{

	return handle_irq_desc(irq_to_desc(irq));

}

EXPORT_SYMBOL_GPL(generic_handle_irq);



#ifdef CONFIG_HANDLE_DOMAIN_IRQ
@@ -668,27 +673,32 @@ int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq, 
			bool lookup, struct pt_regs *regs)

{

	struct pt_regs *old_regs = set_irq_regs(regs);

	unsigned int irq = hwirq;

	struct irq_desc *desc;

	int ret = 0;



	irq_enter();



#ifdef CONFIG_IRQ_DOMAIN

	if (lookup)

		irq = irq_find_mapping(domain, hwirq);

#endif



	if (likely(IS_ENABLED(CONFIG_IRQ_DOMAIN) && lookup)) {

		/* The irqdomain code provides boundary checks */

		desc = irq_resolve_mapping(domain, hwirq);

	} else {

		/*

		 * Some hardware gives randomly wrong interrupts.  Rather

		 * than crashing, do something sensible.

		 */

	if (unlikely(!irq || irq >= nr_irqs)) {

		ack_bad_irq(irq);

		ret = -EINVAL;

		if (unlikely(!hwirq || hwirq >= nr_irqs)) {

			ack_bad_irq(hwirq);

			desc = NULL;

		} else {

		generic_handle_irq(irq);

			desc = irq_to_desc(hwirq);

		}

	}



	if (likely(desc))

		handle_irq_desc(desc);

	else

		ret = -EINVAL;



	irq_exit();

	set_irq_regs(old_regs);

	return ret;
@@ -709,7 +719,7 @@ int handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq, 
		      struct pt_regs *regs)

{

	struct pt_regs *old_regs = set_irq_regs(regs);

	unsigned int irq;

	struct irq_desc *desc;

	int ret = 0;



	/*
@@ -717,14 +727,14 @@ int handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq, 
	 */

	WARN_ON(!in_nmi());



	irq = irq_find_mapping(domain, hwirq);

	desc = irq_resolve_mapping(domain, hwirq);



	/*

	 * ack_bad_irq is not NMI-safe, just report

	 * an invalid interrupt.

	 */

	if (likely(irq))

		generic_handle_irq(irq);

	if (likely(desc))

		handle_irq_desc(desc);

	else

		ret = -EINVAL;