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path: root/kernel/irq/irqdomain.c
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Diffstat (limited to 'kernel/irq/irqdomain.c')
-rw-r--r--kernel/irq/irqdomain.c243
1 files changed, 207 insertions, 36 deletions
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index f1f251479aa6..ac4644e92b49 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -41,6 +41,9 @@ static inline void debugfs_add_domain_dir(struct irq_domain *d) { }
static inline void debugfs_remove_domain_dir(struct irq_domain *d) { }
#endif
+const struct fwnode_operations irqchip_fwnode_ops;
+EXPORT_SYMBOL_GPL(irqchip_fwnode_ops);
+
/**
* irq_domain_alloc_fwnode - Allocate a fwnode_handle suitable for
* identifying an irq domain
@@ -86,7 +89,7 @@ struct fwnode_handle *__irq_domain_alloc_fwnode(unsigned int type, int id,
fwid->type = type;
fwid->name = n;
fwid->data = data;
- fwid->fwnode.type = FWNODE_IRQCHIP;
+ fwid->fwnode.ops = &irqchip_fwnode_ops;
return &fwid->fwnode;
}
EXPORT_SYMBOL_GPL(__irq_domain_alloc_fwnode);
@@ -193,10 +196,8 @@ struct irq_domain *__irq_domain_add(struct fwnode_handle *fwnode, int size,
}
if (!domain->name) {
- if (fwnode) {
- pr_err("Invalid fwnode type (%d) for irqdomain\n",
- fwnode->type);
- }
+ if (fwnode)
+ pr_err("Invalid fwnode type for irqdomain\n");
domain->name = kasprintf(GFP_KERNEL, "unknown-%d",
atomic_inc_return(&unknown_domains));
if (!domain->name) {
@@ -455,6 +456,31 @@ void irq_set_default_host(struct irq_domain *domain)
}
EXPORT_SYMBOL_GPL(irq_set_default_host);
+static void irq_domain_clear_mapping(struct irq_domain *domain,
+ irq_hw_number_t hwirq)
+{
+ if (hwirq < domain->revmap_size) {
+ domain->linear_revmap[hwirq] = 0;
+ } else {
+ mutex_lock(&revmap_trees_mutex);
+ radix_tree_delete(&domain->revmap_tree, hwirq);
+ mutex_unlock(&revmap_trees_mutex);
+ }
+}
+
+static void irq_domain_set_mapping(struct irq_domain *domain,
+ irq_hw_number_t hwirq,
+ struct irq_data *irq_data)
+{
+ if (hwirq < domain->revmap_size) {
+ domain->linear_revmap[hwirq] = irq_data->irq;
+ } else {
+ mutex_lock(&revmap_trees_mutex);
+ radix_tree_insert(&domain->revmap_tree, hwirq, irq_data);
+ mutex_unlock(&revmap_trees_mutex);
+ }
+}
+
void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq)
{
struct irq_data *irq_data = irq_get_irq_data(irq);
@@ -483,13 +509,7 @@ void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq)
domain->mapcount--;
/* Clear reverse map for this hwirq */
- if (hwirq < domain->revmap_size) {
- domain->linear_revmap[hwirq] = 0;
- } else {
- mutex_lock(&revmap_trees_mutex);
- radix_tree_delete(&domain->revmap_tree, hwirq);
- mutex_unlock(&revmap_trees_mutex);
- }
+ irq_domain_clear_mapping(domain, hwirq);
}
int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
@@ -533,13 +553,7 @@ int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
}
domain->mapcount++;
- if (hwirq < domain->revmap_size) {
- domain->linear_revmap[hwirq] = virq;
- } else {
- mutex_lock(&revmap_trees_mutex);
- radix_tree_insert(&domain->revmap_tree, hwirq, irq_data);
- mutex_unlock(&revmap_trees_mutex);
- }
+ irq_domain_set_mapping(domain, hwirq, irq_data);
mutex_unlock(&irq_domain_mutex);
irq_clear_status_flags(virq, IRQ_NOREQUEST);
@@ -931,7 +945,7 @@ static int virq_debug_show(struct seq_file *m, void *private)
struct irq_desc *desc;
struct irq_domain *domain;
struct radix_tree_iter iter;
- void **slot;
+ void __rcu **slot;
int i;
seq_printf(m, " %-16s %-6s %-10s %-10s %s\n",
@@ -1138,16 +1152,9 @@ static void irq_domain_insert_irq(int virq)
for (data = irq_get_irq_data(virq); data; data = data->parent_data) {
struct irq_domain *domain = data->domain;
- irq_hw_number_t hwirq = data->hwirq;
domain->mapcount++;
- if (hwirq < domain->revmap_size) {
- domain->linear_revmap[hwirq] = virq;
- } else {
- mutex_lock(&revmap_trees_mutex);
- radix_tree_insert(&domain->revmap_tree, hwirq, data);
- mutex_unlock(&revmap_trees_mutex);
- }
+ irq_domain_set_mapping(domain, data->hwirq, data);
/* If not already assigned, give the domain the chip's name */
if (!domain->name && data->chip)
@@ -1171,13 +1178,7 @@ static void irq_domain_remove_irq(int virq)
irq_hw_number_t hwirq = data->hwirq;
domain->mapcount--;
- if (hwirq < domain->revmap_size) {
- domain->linear_revmap[hwirq] = 0;
- } else {
- mutex_lock(&revmap_trees_mutex);
- radix_tree_delete(&domain->revmap_tree, hwirq);
- mutex_unlock(&revmap_trees_mutex);
- }
+ irq_domain_clear_mapping(domain, hwirq);
}
}
@@ -1362,7 +1363,8 @@ static void irq_domain_free_irqs_hierarchy(struct irq_domain *domain,
unsigned int irq_base,
unsigned int nr_irqs)
{
- domain->ops->free(domain, irq_base, nr_irqs);
+ if (domain->ops->free)
+ domain->ops->free(domain, irq_base, nr_irqs);
}
int irq_domain_alloc_irqs_hierarchy(struct irq_domain *domain,
@@ -1448,6 +1450,175 @@ out_free_desc:
return ret;
}
+/* The irq_data was moved, fix the revmap to refer to the new location */
+static void irq_domain_fix_revmap(struct irq_data *d)
+{
+ void __rcu **slot;
+
+ if (d->hwirq < d->domain->revmap_size)
+ return; /* Not using radix tree. */
+
+ /* Fix up the revmap. */
+ mutex_lock(&revmap_trees_mutex);
+ slot = radix_tree_lookup_slot(&d->domain->revmap_tree, d->hwirq);
+ if (slot)
+ radix_tree_replace_slot(&d->domain->revmap_tree, slot, d);
+ mutex_unlock(&revmap_trees_mutex);
+}
+
+/**
+ * irq_domain_push_irq() - Push a domain in to the top of a hierarchy.
+ * @domain: Domain to push.
+ * @virq: Irq to push the domain in to.
+ * @arg: Passed to the irq_domain_ops alloc() function.
+ *
+ * For an already existing irqdomain hierarchy, as might be obtained
+ * via a call to pci_enable_msix(), add an additional domain to the
+ * head of the processing chain. Must be called before request_irq()
+ * has been called.
+ */
+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_desc *desc;
+ int rv = 0;
+
+ /*
+ * Check that no action has been set, which indicates the virq
+ * is in a state where this function doesn't have to deal with
+ * races between interrupt handling and maintaining the
+ * hierarchy. This will catch gross misuse. Attempting to
+ * make the check race free would require holding locks across
+ * calls to struct irq_domain_ops->alloc(), which could lead
+ * to deadlock, so we just do a simple check before starting.
+ */
+ desc = irq_to_desc(virq);
+ if (!desc)
+ return -EINVAL;
+ if (WARN_ON(desc->action))
+ return -EBUSY;
+
+ if (domain == NULL)
+ return -EINVAL;
+
+ if (WARN_ON(!irq_domain_is_hierarchy(domain)))
+ return -EINVAL;
+
+ if (!root_irq_data)
+ return -EINVAL;
+
+ if (domain->parent != root_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)
+ return -ENOMEM;
+
+ mutex_lock(&irq_domain_mutex);
+
+ /* Copy the original irq_data. */
+ *child_irq_data = *root_irq_data;
+
+ /*
+ * Overwrite the root_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;
+
+ /* 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;
+ goto error;
+ }
+
+ irq_domain_fix_revmap(child_irq_data);
+ irq_domain_set_mapping(domain, root_irq_data->hwirq, root_irq_data);
+
+error:
+ mutex_unlock(&irq_domain_mutex);
+
+ return rv;
+}
+EXPORT_SYMBOL_GPL(irq_domain_push_irq);
+
+/**
+ * irq_domain_pop_irq() - Remove a domain from the top of a hierarchy.
+ * @domain: Domain to remove.
+ * @virq: Irq to remove the domain from.
+ *
+ * Undo the effects of a call to irq_domain_push_irq(). Must be
+ * called either before request_irq() or after free_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 *tmp_irq_data;
+ struct irq_desc *desc;
+
+ /*
+ * Check that no action is set, which indicates the virq is in
+ * a state where this function doesn't have to deal with races
+ * between interrupt handling and maintaining the hierarchy.
+ * This will catch gross misuse. Attempting to make the check
+ * race free would require holding locks across calls to
+ * struct irq_domain_ops->free(), which could lead to
+ * deadlock, so we just do a simple check before starting.
+ */
+ desc = irq_to_desc(virq);
+ if (!desc)
+ return -EINVAL;
+ if (WARN_ON(desc->action))
+ return -EBUSY;
+
+ if (domain == NULL)
+ return -EINVAL;
+
+ if (!root_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))
+ return -EINVAL;
+
+ if (WARN_ON(root_irq_data->domain != domain))
+ return -EINVAL;
+
+ child_irq_data = root_irq_data->parent_data;
+ if (WARN_ON(!child_irq_data))
+ return -EINVAL;
+
+ mutex_lock(&irq_domain_mutex);
+
+ root_irq_data->parent_data = NULL;
+
+ irq_domain_clear_mapping(domain, root_irq_data->hwirq);
+ irq_domain_free_irqs_hierarchy(domain, virq, 1);
+
+ /* Restore the original irq_data. */
+ *root_irq_data = *child_irq_data;
+
+ irq_domain_fix_revmap(root_irq_data);
+
+ mutex_unlock(&irq_domain_mutex);
+
+ kfree(child_irq_data);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(irq_domain_pop_irq);
+
/**
* irq_domain_free_irqs - Free IRQ number and associated data structures
* @virq: base IRQ number