Re: [PATCH 1/8] irqdomain: Support removal of IRQ domains.

[Grant Likely <grant.likely@secretlab.ca>]

On Sat, 19 May 2012 15:11:41 +0900, Paul Mundt <lethal@linux-sh.org> wrote:
> Now that IRQ domains are being used by modules it's necessary to support
> removing them, too. This adds a new irq_domain_remove() routine for doing
> the bulk of the heavy lifting. It's left as an exercise to the caller to
> ensure all mappings have been appropriatey disposed of before attempting
> to remove the domain.
> 
> Signed-off-by: Paul Mundt <lethal@linux-sh.org>

Applied, thanks.

g.

> ---
>  include/linux/irqdomain.h |    4 ++-
>  kernel/irq/irqdomain.c    |   61 +++++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 62 insertions(+), 3 deletions(-)
> 
> diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
> index c65740d..a796dbf 100644
> --- a/include/linux/irqdomain.h
> +++ b/include/linux/irqdomain.h
> @@ -141,10 +141,12 @@ static inline struct irq_domain *irq_domain_add_legacy_isa(
>  	return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,
>  				     host_data);
>  }
> +
> +extern void irq_domain_remove(struct irq_domain *host);
> +
>  extern struct irq_domain *irq_find_host(struct device_node *node);
>  extern void irq_set_default_host(struct irq_domain *host);
>  
> -
>  extern unsigned int irq_create_mapping(struct irq_domain *host,
>  				       irq_hw_number_t hwirq);
>  extern void irq_dispose_mapping(unsigned int virq);
> diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
> index 0e0ba5f..9cae0b2 100644
> --- a/kernel/irq/irqdomain.c
> +++ b/kernel/irq/irqdomain.c
> @@ -56,6 +56,12 @@ static struct irq_domain *irq_domain_alloc(struct device_node *of_node,
>  	return domain;
>  }
>  
> +static void irq_domain_free(struct irq_domain *domain)
> +{
> +	of_node_put(domain->of_node);
> +	kfree(domain);
> +}
> +
>  static void irq_domain_add(struct irq_domain *domain)
>  {
>  	mutex_lock(&irq_domain_mutex);
> @@ -65,6 +71,58 @@ static void irq_domain_add(struct irq_domain *domain)
>  		 domain->revmap_type, domain);
>  }
>  
> +/**
> + * irq_domain_remove() - Remove an irq domain.
> + * @domain: domain to remove
> + *
> + * This routine is used to remove an irq domain. The caller must ensure
> + * that all mappings within the domain have been disposed of prior to
> + * use, depending on the revmap type.
> + */
> +void irq_domain_remove(struct irq_domain *domain)
> +{
> +	mutex_lock(&irq_domain_mutex);
> +
> +	switch (domain->revmap_type) {
> +	case IRQ_DOMAIN_MAP_LEGACY:
> +		/*
> +		 * Legacy domains don't manage their own irq_desc
> +		 * allocations, we expect the caller to handle irq_desc
> +		 * freeing on their own.
> +		 */
> +		break;
> +	case IRQ_DOMAIN_MAP_TREE:
> +		/*
> +		 * radix_tree_delete() takes care of destroying the root
> +		 * node when all entries are removed. Shout if there are
> +		 * any mappings left.
> +		 */
> +		WARN_ON(domain->revmap_data.tree.height);
> +		break;
> +	case IRQ_DOMAIN_MAP_LINEAR:
> +		kfree(domain->revmap_data.linear.revmap);
> +		domain->revmap_data.linear.size = 0;
> +		break;
> +	case IRQ_DOMAIN_MAP_NOMAP:
> +		break;
> +	}
> +
> +	list_del(&domain->link);
> +
> +	/*
> +	 * If the going away domain is the default one, reset it.
> +	 */
> +	if (unlikely(irq_default_domain = domain))
> +		irq_set_default_host(NULL);
> +
> +	mutex_unlock(&irq_domain_mutex);
> +
> +	pr_debug("irq: Removed domain of type %d @0x%p\n",
> +		 domain->revmap_type, domain);
> +
> +	irq_domain_free(domain);
> +}
> +
>  static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain,
>  					     irq_hw_number_t hwirq)
>  {
> @@ -117,8 +175,7 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
>  
>  		if (WARN_ON(!irq_data || irq_data->domain)) {
>  			mutex_unlock(&irq_domain_mutex);
> -			of_node_put(domain->of_node);
> -			kfree(domain);
> +			irq_domain_free(domain);
>  			return NULL;
>  		}
>  	}
> -- 
> 1.7.9.rc0.28.g0e1cf
> 

-- 
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.