From: Johan Hovold johan+linaro@kernel.org
Refactor __irq_domain_alloc_irqs() so that it can be called internally while holding the irq_domain_mutex.
This will be used to fix a shared-interrupt mapping race, hence the Fixes tag.
Fixes: b62b2cf5759b ("irqdomain: Fix handling of type settings for existing mappings") Cc: stable@vger.kernel.org # 4.8 Tested-by: Hsin-Yi Wang hsinyi@chromium.org Tested-by: Mark-PK Tsai mark-pk.tsai@mediatek.com Signed-off-by: Johan Hovold johan+linaro@kernel.org Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20230213104302.17307-6-johan+linaro@kernel.org [ johan: backport to 5.15; adjust context ] Signed-off-by: Johan Hovold johan+linaro@kernel.org --- kernel/irq/irqdomain.c | 88 +++++++++++++++++++++++------------------- 1 file changed, 48 insertions(+), 40 deletions(-)
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 298f9c12023c..f95196063884 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -1464,40 +1464,12 @@ int irq_domain_alloc_irqs_hierarchy(struct irq_domain *domain, return domain->ops->alloc(domain, irq_base, nr_irqs, arg); }
-/** - * __irq_domain_alloc_irqs - Allocate IRQs from domain - * @domain: domain to allocate from - * @irq_base: allocate specified IRQ number if irq_base >= 0 - * @nr_irqs: number of IRQs to allocate - * @node: NUMA node id for memory allocation - * @arg: domain specific argument - * @realloc: IRQ descriptors have already been allocated if true - * @affinity: Optional irq affinity mask for multiqueue devices - * - * Allocate IRQ numbers and initialized all data structures to support - * hierarchy IRQ domains. - * Parameter @realloc is mainly to support legacy IRQs. - * Returns error code or allocated IRQ number - * - * The whole process to setup an IRQ has been split into two steps. - * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ - * descriptor and required hardware resources. The second step, - * irq_domain_activate_irq(), is to program the hardware with preallocated - * resources. In this way, it's easier to rollback when failing to - * allocate resources. - */ -int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base, - unsigned int nr_irqs, int node, void *arg, - bool realloc, const struct irq_affinity_desc *affinity) +static int irq_domain_alloc_irqs_locked(struct irq_domain *domain, int irq_base, + unsigned int nr_irqs, int node, void *arg, + bool realloc, const struct irq_affinity_desc *affinity) { int i, ret, virq;
- if (domain == NULL) { - domain = irq_default_domain; - if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n")) - return -EINVAL; - } - if (realloc && irq_base >= 0) { virq = irq_base; } else { @@ -1516,24 +1488,18 @@ int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base, goto out_free_desc; }
- mutex_lock(&irq_domain_mutex); ret = irq_domain_alloc_irqs_hierarchy(domain, virq, nr_irqs, arg); - if (ret < 0) { - mutex_unlock(&irq_domain_mutex); + if (ret < 0) goto out_free_irq_data; - }
for (i = 0; i < nr_irqs; i++) { ret = irq_domain_trim_hierarchy(virq + i); - if (ret) { - mutex_unlock(&irq_domain_mutex); + if (ret) goto out_free_irq_data; - } } - + for (i = 0; i < nr_irqs; i++) irq_domain_insert_irq(virq + i); - mutex_unlock(&irq_domain_mutex);
return virq;
@@ -1544,6 +1510,48 @@ int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base, return ret; }
+/** + * __irq_domain_alloc_irqs - Allocate IRQs from domain + * @domain: domain to allocate from + * @irq_base: allocate specified IRQ number if irq_base >= 0 + * @nr_irqs: number of IRQs to allocate + * @node: NUMA node id for memory allocation + * @arg: domain specific argument + * @realloc: IRQ descriptors have already been allocated if true + * @affinity: Optional irq affinity mask for multiqueue devices + * + * Allocate IRQ numbers and initialized all data structures to support + * hierarchy IRQ domains. + * Parameter @realloc is mainly to support legacy IRQs. + * Returns error code or allocated IRQ number + * + * The whole process to setup an IRQ has been split into two steps. + * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ + * descriptor and required hardware resources. The second step, + * irq_domain_activate_irq(), is to program the hardware with preallocated + * resources. In this way, it's easier to rollback when failing to + * allocate resources. + */ +int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base, + unsigned int nr_irqs, int node, void *arg, + bool realloc, const struct irq_affinity_desc *affinity) +{ + int ret; + + if (domain == NULL) { + domain = irq_default_domain; + if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n")) + return -EINVAL; + } + + mutex_lock(&irq_domain_mutex); + ret = irq_domain_alloc_irqs_locked(domain, irq_base, nr_irqs, node, arg, + realloc, affinity); + mutex_unlock(&irq_domain_mutex); + + 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) {