Re: [patch 09/16] genirq: Add generic msi irq domain support

["Yun Wu (Abel)" <wuyun.wu@huawei.com>]

On 2014/11/18 20:49, Jiang Liu wrote:

> 
> On 2014/11/18 20:07, Yun Wu (Abel) wrote:
>> On 2014/11/12 21:43, Thomas Gleixner wrote:
>>
>>> From: Jiang Liu <jiang.liu@linux.intel.com>
> <snip>
>>> +static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
>>> +			    unsigned int nr_irqs, void *arg)
>>> +{
>>> +	struct msi_domain_info *info = domain->host_data;
>>> +	struct msi_domain_ops *ops = info->ops;
>>> +	irq_hw_number_t hwirq = ops->get_hwirq(info, arg);
>>> +	int i, ret;
>>> +
>>> +	if (irq_find_mapping(domain, hwirq) > 0)
>>> +		return -EEXIST;
>>
>> I think we need to check range here.
>> I fixed this by applying a patch showed in the bottom.
> Hi Yun,
> 	Yes, we have some assumptions here about the way the interface
> will be used for. Will improve it in future patches.
> Regards!
> Gerry
>>

OK. Just note that don't forget to check my second inline comment below. :)

>>> +
>>> +	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
>>> +	if (ret < 0)
>>> +		return ret;
>>> +
>>> +	for (i = 0; i < nr_irqs; i++) {
>>> +		ret = ops->msi_init(domain, info, virq + i, hwirq + i, arg);
>>> +		if (ret < 0) {
>>> +			if (ops->msi_free) {
>>> +				for (i--; i > 0; i--)
>>
>> while (i--) ?
>>
Here.


Thanks,
	Abel

>>
>>> +					ops->msi_free(domain, info, virq + i);
>>> +			}
>>> +			irq_domain_free_irqs_top(domain, virq, nr_irqs);
>>> +			return ret;
>>> +		}
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static void msi_domain_free(struct irq_domain *domain, unsigned int virq,
>>> +			    unsigned int nr_irqs)
>>> +{
>>> +	struct msi_domain_info *info = domain->host_data;
>>> +	int i;
>>> +
>>> +	if (info->ops->msi_free) {
>>> +		for (i = 0; i < nr_irqs; i++)
>>> +			info->ops->msi_free(domain, info, virq + i);
>>> +	}
>>> +	irq_domain_free_irqs_top(domain, virq, nr_irqs);
>>> +}
>>> +
>>> +static struct irq_domain_ops msi_domain_ops = {
>>> +	.alloc		= msi_domain_alloc,
>>> +	.free		= msi_domain_free,
>>> +	.activate	= msi_domain_activate,
>>> +	.deactivate	= msi_domain_deactivate,
>>> +};
>>> +
>>> +struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
>>> +					 struct msi_domain_info *info,
>>> +					 struct irq_domain *parent)
>>> +{
>>> +	struct irq_domain *domain;
>>> +
>>> +	domain = irq_domain_add_tree(of_node, &msi_domain_ops, info);
>>> +	if (domain)
>>> +		domain->parent = parent;
>>> +
>>> +	return domain;
>>> +}
>>> +
>>> +struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain)
>>> +{
>>> +	return (struct msi_domain_info *)domain->host_data;
>>> +}
>>> +
>>> +#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */
>>>
>>>
>>
>> diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
>> index cc18182..6d1be00 100644
>> --- a/kernel/irq/irqdomain.c
>> +++ b/kernel/irq/irqdomain.c
>> @@ -568,6 +568,34 @@ unsigned int irq_find_mapping(struct irq_domain *domain,
>>  }
>>  EXPORT_SYMBOL_GPL(irq_find_mapping);
>>
>> +/**
>> + * irq_find_mapping_many() - Find a range of linux irqs from a range of hwirqs.
>> + * @domain:	domain owning these hardware interrupts
>> + * @hwirq:	start hardware irq number in @domain space
>> + * @count:	number of interrupts to find
>> + *
>> + * Returns the first linux irq number on success, or 0 when not found, or error.
>> + */
>> +int irq_find_mapping_many(struct irq_domain *domain, irq_hw_number_t hwirq,
>> +			  int count)
>> +{
>> +	unsigned int from;
>> +	int i;
>> +
>> +	for (i = from = 0; i < count; i++) {
>> +		if (!from) {
>> +			from = irq_find_mapping(domain, hwirq + i);
>> +			if (from && i)
>> +				return -1;
>> +		} else if ((from + i) != irq_find_mapping(domain, hwirq + i)) {
>> +			return -1;
>> +		}
>> +	}
>> +
>> +	return from;
>> +}
>> +EXPORT_SYMBOL_GPL(irq_find_mapping_many);
>> +
>>  #ifdef CONFIG_IRQ_DOMAIN_DEBUG
>>  static int virq_debug_show(struct seq_file *m, void *private)
>>  {
>>
>>
>>
> 
> .
>