[PATCH v6 11/20] irqdomain: Clean up irq_domain_push/pop_irq()

From: Johan Hovold
Date: Mon Feb 13 2023 - 05:43:30 EST


The irq_domain_push_irq() interface is used to add a new (outmost) level
to a hierarchical domain after IRQs have been allocated.

Possibly due to differing mental images of hierarchical domains, the
names used for the irq_data variables make these functions much harder
to understand than what they need to be.

Rename the struct irq_data pointer to the data embedded in the
descriptor as simply 'irq_data' and refer to the data allocated by this
interface as 'parent_irq_data' so that the names reflect how
hierarchical domains are implemented.

Reviewed-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
Tested-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx>
Tested-by: Mark-PK Tsai <mark-pk.tsai@xxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
---
kernel/irq/irqdomain.c | 65 +++++++++++++++++++++---------------------
1 file changed, 32 insertions(+), 33 deletions(-)

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 7785b3352e60..2213d972f083 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1598,8 +1598,8 @@ static void irq_domain_fix_revmap(struct irq_data *d)
*/
int irq_domain_push_irq(struct irq_domain *domain, int virq, void *arg)
{
- struct irq_data *child_irq_data;
- struct irq_data *root_irq_data = irq_get_irq_data(virq);
+ struct irq_data *irq_data = irq_get_irq_data(virq);
+ struct irq_data *parent_irq_data;
struct irq_desc *desc;
int rv = 0;

@@ -1624,45 +1624,44 @@ int irq_domain_push_irq(struct irq_domain *domain, int virq, void *arg)
if (WARN_ON(!irq_domain_is_hierarchy(domain)))
return -EINVAL;

- if (!root_irq_data)
+ if (!irq_data)
return -EINVAL;

- if (domain->parent != root_irq_data->domain)
+ if (domain->parent != irq_data->domain)
return -EINVAL;

- child_irq_data = kzalloc_node(sizeof(*child_irq_data), GFP_KERNEL,
- irq_data_get_node(root_irq_data));
- if (!child_irq_data)
+ parent_irq_data = kzalloc_node(sizeof(*parent_irq_data), GFP_KERNEL,
+ irq_data_get_node(irq_data));
+ if (!parent_irq_data)
return -ENOMEM;

mutex_lock(&irq_domain_mutex);

/* Copy the original irq_data. */
- *child_irq_data = *root_irq_data;
+ *parent_irq_data = *irq_data;

/*
- * Overwrite the root_irq_data, which is embedded in struct
- * irq_desc, with values for this domain.
+ * Overwrite the irq_data, which is embedded in struct irq_desc, with
+ * values for this domain.
*/
- root_irq_data->parent_data = child_irq_data;
- root_irq_data->domain = domain;
- root_irq_data->mask = 0;
- root_irq_data->hwirq = 0;
- root_irq_data->chip = NULL;
- root_irq_data->chip_data = NULL;
+ irq_data->parent_data = parent_irq_data;
+ irq_data->domain = domain;
+ irq_data->mask = 0;
+ irq_data->hwirq = 0;
+ irq_data->chip = NULL;
+ irq_data->chip_data = NULL;

/* May (probably does) set hwirq, chip, etc. */
rv = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
if (rv) {
/* Restore the original irq_data. */
- *root_irq_data = *child_irq_data;
- kfree(child_irq_data);
+ *irq_data = *parent_irq_data;
+ kfree(parent_irq_data);
goto error;
}

- irq_domain_fix_revmap(child_irq_data);
- irq_domain_set_mapping(domain, root_irq_data->hwirq, root_irq_data);
-
+ irq_domain_fix_revmap(parent_irq_data);
+ irq_domain_set_mapping(domain, irq_data->hwirq, irq_data);
error:
mutex_unlock(&irq_domain_mutex);

@@ -1680,8 +1679,8 @@ EXPORT_SYMBOL_GPL(irq_domain_push_irq);
*/
int irq_domain_pop_irq(struct irq_domain *domain, int virq)
{
- struct irq_data *root_irq_data = irq_get_irq_data(virq);
- struct irq_data *child_irq_data;
+ struct irq_data *irq_data = irq_get_irq_data(virq);
+ struct irq_data *parent_irq_data;
struct irq_data *tmp_irq_data;
struct irq_desc *desc;

@@ -1703,37 +1702,37 @@ int irq_domain_pop_irq(struct irq_domain *domain, int virq)
if (domain == NULL)
return -EINVAL;

- if (!root_irq_data)
+ if (!irq_data)
return -EINVAL;

tmp_irq_data = irq_domain_get_irq_data(domain, virq);

/* We can only "pop" if this domain is at the top of the list */
- if (WARN_ON(root_irq_data != tmp_irq_data))
+ if (WARN_ON(irq_data != tmp_irq_data))
return -EINVAL;

- if (WARN_ON(root_irq_data->domain != domain))
+ if (WARN_ON(irq_data->domain != domain))
return -EINVAL;

- child_irq_data = root_irq_data->parent_data;
- if (WARN_ON(!child_irq_data))
+ parent_irq_data = irq_data->parent_data;
+ if (WARN_ON(!parent_irq_data))
return -EINVAL;

mutex_lock(&irq_domain_mutex);

- root_irq_data->parent_data = NULL;
+ irq_data->parent_data = NULL;

- irq_domain_clear_mapping(domain, root_irq_data->hwirq);
+ irq_domain_clear_mapping(domain, irq_data->hwirq);
irq_domain_free_irqs_hierarchy(domain, virq, 1);

/* Restore the original irq_data. */
- *root_irq_data = *child_irq_data;
+ *irq_data = *parent_irq_data;

- irq_domain_fix_revmap(root_irq_data);
+ irq_domain_fix_revmap(irq_data);

mutex_unlock(&irq_domain_mutex);

- kfree(child_irq_data);
+ kfree(parent_irq_data);

return 0;
}
--
2.39.1