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authorThomas Gleixner <tglx@linutronix.de>2019-02-23 10:53:31 +0100
committerThomas Gleixner <tglx@linutronix.de>2019-02-23 10:53:31 +0100
commita324ca9cad4736252c33c1e28cffe1d87f262d03 (patch)
treeda64e14dd8432602634773b52073928c50dfb85c /kernel/irq/manage.c
parent4e6b26d23dc1faee318796d5c7f91b5692b1e6be (diff)
parent28528fca4908142bd1a3247956cba56c9c667d71 (diff)
downloadlinux-a324ca9cad4736252c33c1e28cffe1d87f262d03.tar.bz2
Merge tag 'irqchip-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates from Marc Zyngier - Core pseudo-NMI handling code - Allow the default irq domain to be retrieved - A new interrupt controller for the Loongson LS1X platform - Affinity support for the SiFive PLIC - Better support for the iMX irqsteer driver - NUMA aware memory allocations for GICv3 - A handful of other fixes (i8259, GICv3, PLIC)
Diffstat (limited to 'kernel/irq/manage.c')
-rw-r--r--kernel/irq/manage.c405
1 files changed, 404 insertions, 1 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 3f8a8ebda484..9ec34a2a6638 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -341,7 +341,7 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
/* The release function is promised process context */
might_sleep();
- if (!desc)
+ if (!desc || desc->istate & IRQS_NMI)
return -EINVAL;
/* Complete initialisation of *notify */
@@ -553,6 +553,21 @@ bool disable_hardirq(unsigned int irq)
}
EXPORT_SYMBOL_GPL(disable_hardirq);
+/**
+ * disable_nmi_nosync - disable an nmi without waiting
+ * @irq: Interrupt to disable
+ *
+ * Disable the selected interrupt line. Disables and enables are
+ * nested.
+ * The interrupt to disable must have been requested through request_nmi.
+ * Unlike disable_nmi(), this function does not ensure existing
+ * instances of the IRQ handler have completed before returning.
+ */
+void disable_nmi_nosync(unsigned int irq)
+{
+ disable_irq_nosync(irq);
+}
+
void __enable_irq(struct irq_desc *desc)
{
switch (desc->depth) {
@@ -609,6 +624,20 @@ out:
}
EXPORT_SYMBOL(enable_irq);
+/**
+ * enable_nmi - enable handling of an nmi
+ * @irq: Interrupt to enable
+ *
+ * The interrupt to enable must have been requested through request_nmi.
+ * Undoes the effect of one call to disable_nmi(). If this
+ * matches the last disable, processing of interrupts on this
+ * IRQ line is re-enabled.
+ */
+void enable_nmi(unsigned int irq)
+{
+ enable_irq(irq);
+}
+
static int set_irq_wake_real(unsigned int irq, unsigned int on)
{
struct irq_desc *desc = irq_to_desc(irq);
@@ -644,6 +673,12 @@ int irq_set_irq_wake(unsigned int irq, unsigned int on)
if (!desc)
return -EINVAL;
+ /* Don't use NMIs as wake up interrupts please */
+ if (desc->istate & IRQS_NMI) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
/* wakeup-capable irqs can be shared between drivers that
* don't need to have the same sleep mode behaviors.
*/
@@ -666,6 +701,8 @@ int irq_set_irq_wake(unsigned int irq, unsigned int on)
irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
}
}
+
+out_unlock:
irq_put_desc_busunlock(desc, flags);
return ret;
}
@@ -1129,6 +1166,39 @@ static void irq_release_resources(struct irq_desc *desc)
c->irq_release_resources(d);
}
+static bool irq_supports_nmi(struct irq_desc *desc)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+ /* Only IRQs directly managed by the root irqchip can be set as NMI */
+ if (d->parent_data)
+ return false;
+#endif
+ /* Don't support NMIs for chips behind a slow bus */
+ if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock)
+ return false;
+
+ return d->chip->flags & IRQCHIP_SUPPORTS_NMI;
+}
+
+static int irq_nmi_setup(struct irq_desc *desc)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+ struct irq_chip *c = d->chip;
+
+ return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL;
+}
+
+static void irq_nmi_teardown(struct irq_desc *desc)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+ struct irq_chip *c = d->chip;
+
+ if (c->irq_nmi_teardown)
+ c->irq_nmi_teardown(d);
+}
+
static int
setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
{
@@ -1303,9 +1373,17 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
* fields must have IRQF_SHARED set and the bits which
* set the trigger type must match. Also all must
* agree on ONESHOT.
+ * Interrupt lines used for NMIs cannot be shared.
*/
unsigned int oldtype;
+ if (desc->istate & IRQS_NMI) {
+ pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
+ new->name, irq, desc->irq_data.chip->name);
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
/*
* If nobody did set the configuration before, inherit
* the one provided by the requester.
@@ -1757,6 +1835,59 @@ const void *free_irq(unsigned int irq, void *dev_id)
}
EXPORT_SYMBOL(free_irq);
+/* This function must be called with desc->lock held */
+static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)
+{
+ const char *devname = NULL;
+
+ desc->istate &= ~IRQS_NMI;
+
+ if (!WARN_ON(desc->action == NULL)) {
+ irq_pm_remove_action(desc, desc->action);
+ devname = desc->action->name;
+ unregister_handler_proc(irq, desc->action);
+
+ kfree(desc->action);
+ desc->action = NULL;
+ }
+
+ irq_settings_clr_disable_unlazy(desc);
+ irq_shutdown(desc);
+
+ irq_release_resources(desc);
+
+ irq_chip_pm_put(&desc->irq_data);
+ module_put(desc->owner);
+
+ return devname;
+}
+
+const void *free_nmi(unsigned int irq, void *dev_id)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ unsigned long flags;
+ const void *devname;
+
+ if (!desc || WARN_ON(!(desc->istate & IRQS_NMI)))
+ return NULL;
+
+ if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
+ return NULL;
+
+ /* NMI still enabled */
+ if (WARN_ON(desc->depth == 0))
+ disable_nmi_nosync(irq);
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+
+ irq_nmi_teardown(desc);
+ devname = __cleanup_nmi(irq, desc);
+
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ return devname;
+}
+
/**
* request_threaded_irq - allocate an interrupt line
* @irq: Interrupt line to allocate
@@ -1926,6 +2057,101 @@ int request_any_context_irq(unsigned int irq, irq_handler_t handler,
}
EXPORT_SYMBOL_GPL(request_any_context_irq);
+/**
+ * request_nmi - allocate an interrupt line for NMI delivery
+ * @irq: Interrupt line to allocate
+ * @handler: Function to be called when the IRQ occurs.
+ * Threaded handler for threaded interrupts.
+ * @irqflags: Interrupt type flags
+ * @name: An ascii name for the claiming device
+ * @dev_id: A cookie passed back to the handler function
+ *
+ * This call allocates interrupt resources and enables the
+ * interrupt line and IRQ handling. It sets up the IRQ line
+ * to be handled as an NMI.
+ *
+ * An interrupt line delivering NMIs cannot be shared and IRQ handling
+ * cannot be threaded.
+ *
+ * Interrupt lines requested for NMI delivering must produce per cpu
+ * interrupts and have auto enabling setting disabled.
+ *
+ * Dev_id must be globally unique. Normally the address of the
+ * device data structure is used as the cookie. Since the handler
+ * receives this value it makes sense to use it.
+ *
+ * If the interrupt line cannot be used to deliver NMIs, function
+ * will fail and return a negative value.
+ */
+int request_nmi(unsigned int irq, irq_handler_t handler,
+ unsigned long irqflags, const char *name, void *dev_id)
+{
+ struct irqaction *action;
+ struct irq_desc *desc;
+ unsigned long flags;
+ int retval;
+
+ if (irq == IRQ_NOTCONNECTED)
+ return -ENOTCONN;
+
+ /* NMI cannot be shared, used for Polling */
+ if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL))
+ return -EINVAL;
+
+ if (!(irqflags & IRQF_PERCPU))
+ return -EINVAL;
+
+ if (!handler)
+ return -EINVAL;
+
+ desc = irq_to_desc(irq);
+
+ if (!desc || irq_settings_can_autoenable(desc) ||
+ !irq_settings_can_request(desc) ||
+ WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
+ !irq_supports_nmi(desc))
+ return -EINVAL;
+
+ action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
+ if (!action)
+ return -ENOMEM;
+
+ action->handler = handler;
+ action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING;
+ action->name = name;
+ action->dev_id = dev_id;
+
+ retval = irq_chip_pm_get(&desc->irq_data);
+ if (retval < 0)
+ goto err_out;
+
+ retval = __setup_irq(irq, desc, action);
+ if (retval)
+ goto err_irq_setup;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+
+ /* Setup NMI state */
+ desc->istate |= IRQS_NMI;
+ retval = irq_nmi_setup(desc);
+ if (retval) {
+ __cleanup_nmi(irq, desc);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+ return -EINVAL;
+ }
+
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ return 0;
+
+err_irq_setup:
+ irq_chip_pm_put(&desc->irq_data);
+err_out:
+ kfree(action);
+
+ return retval;
+}
+
void enable_percpu_irq(unsigned int irq, unsigned int type)
{
unsigned int cpu = smp_processor_id();
@@ -1960,6 +2186,11 @@ out:
}
EXPORT_SYMBOL_GPL(enable_percpu_irq);
+void enable_percpu_nmi(unsigned int irq, unsigned int type)
+{
+ enable_percpu_irq(irq, type);
+}
+
/**
* irq_percpu_is_enabled - Check whether the per cpu irq is enabled
* @irq: Linux irq number to check for
@@ -1999,6 +2230,11 @@ void disable_percpu_irq(unsigned int irq)
}
EXPORT_SYMBOL_GPL(disable_percpu_irq);
+void disable_percpu_nmi(unsigned int irq)
+{
+ disable_percpu_irq(irq);
+}
+
/*
* Internal function to unregister a percpu irqaction.
*/
@@ -2030,6 +2266,8 @@ static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_
/* Found it - now remove it from the list of entries: */
desc->action = NULL;
+ desc->istate &= ~IRQS_NMI;
+
raw_spin_unlock_irqrestore(&desc->lock, flags);
unregister_handler_proc(irq, action);
@@ -2083,6 +2321,19 @@ void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
}
EXPORT_SYMBOL_GPL(free_percpu_irq);
+void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ if (!desc || !irq_settings_is_per_cpu_devid(desc))
+ return;
+
+ if (WARN_ON(!(desc->istate & IRQS_NMI)))
+ return;
+
+ kfree(__free_percpu_irq(irq, dev_id));
+}
+
/**
* setup_percpu_irq - setup a per-cpu interrupt
* @irq: Interrupt line to setup
@@ -2173,6 +2424,158 @@ int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
EXPORT_SYMBOL_GPL(__request_percpu_irq);
/**
+ * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery
+ * @irq: Interrupt line to allocate
+ * @handler: Function to be called when the IRQ occurs.
+ * @name: An ascii name for the claiming device
+ * @dev_id: A percpu cookie passed back to the handler function
+ *
+ * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
+ * have to be setup on each CPU by calling prepare_percpu_nmi() before
+ * being enabled on the same CPU by using enable_percpu_nmi().
+ *
+ * Dev_id must be globally unique. It is a per-cpu variable, and
+ * the handler gets called with the interrupted CPU's instance of
+ * that variable.
+ *
+ * Interrupt lines requested for NMI delivering should have auto enabling
+ * setting disabled.
+ *
+ * If the interrupt line cannot be used to deliver NMIs, function
+ * will fail returning a negative value.
+ */
+int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
+ const char *name, void __percpu *dev_id)
+{
+ struct irqaction *action;
+ struct irq_desc *desc;
+ unsigned long flags;
+ int retval;
+
+ if (!handler)
+ return -EINVAL;
+
+ desc = irq_to_desc(irq);
+
+ if (!desc || !irq_settings_can_request(desc) ||
+ !irq_settings_is_per_cpu_devid(desc) ||
+ irq_settings_can_autoenable(desc) ||
+ !irq_supports_nmi(desc))
+ return -EINVAL;
+
+ /* The line cannot already be NMI */
+ if (desc->istate & IRQS_NMI)
+ return -EINVAL;
+
+ action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
+ if (!action)
+ return -ENOMEM;
+
+ action->handler = handler;
+ action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
+ | IRQF_NOBALANCING;
+ action->name = name;
+ action->percpu_dev_id = dev_id;
+
+ retval = irq_chip_pm_get(&desc->irq_data);
+ if (retval < 0)
+ goto err_out;
+
+ retval = __setup_irq(irq, desc, action);
+ if (retval)
+ goto err_irq_setup;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ desc->istate |= IRQS_NMI;
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ return 0;
+
+err_irq_setup:
+ irq_chip_pm_put(&desc->irq_data);
+err_out:
+ kfree(action);
+
+ return retval;
+}
+
+/**
+ * prepare_percpu_nmi - performs CPU local setup for NMI delivery
+ * @irq: Interrupt line to prepare for NMI delivery
+ *
+ * This call prepares an interrupt line to deliver NMI on the current CPU,
+ * before that interrupt line gets enabled with enable_percpu_nmi().
+ *
+ * As a CPU local operation, this should be called from non-preemptible
+ * context.
+ *
+ * If the interrupt line cannot be used to deliver NMIs, function
+ * will fail returning a negative value.
+ */
+int prepare_percpu_nmi(unsigned int irq)
+{
+ unsigned long flags;
+ struct irq_desc *desc;
+ int ret = 0;
+
+ WARN_ON(preemptible());
+
+ desc = irq_get_desc_lock(irq, &flags,
+ IRQ_GET_DESC_CHECK_PERCPU);
+ if (!desc)
+ return -EINVAL;
+
+ if (WARN(!(desc->istate & IRQS_NMI),
+ KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",
+ irq)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = irq_nmi_setup(desc);
+ if (ret) {
+ pr_err("Failed to setup NMI delivery: irq %u\n", irq);
+ goto out;
+ }
+
+out:
+ irq_put_desc_unlock(desc, flags);
+ return ret;
+}
+
+/**
+ * teardown_percpu_nmi - undoes NMI setup of IRQ line
+ * @irq: Interrupt line from which CPU local NMI configuration should be
+ * removed
+ *
+ * This call undoes the setup done by prepare_percpu_nmi().
+ *
+ * IRQ line should not be enabled for the current CPU.
+ *
+ * As a CPU local operation, this should be called from non-preemptible
+ * context.
+ */
+void teardown_percpu_nmi(unsigned int irq)
+{
+ unsigned long flags;
+ struct irq_desc *desc;
+
+ WARN_ON(preemptible());
+
+ desc = irq_get_desc_lock(irq, &flags,
+ IRQ_GET_DESC_CHECK_PERCPU);
+ if (!desc)
+ return;
+
+ if (WARN_ON(!(desc->istate & IRQS_NMI)))
+ goto out;
+
+ irq_nmi_teardown(desc);
+out:
+ irq_put_desc_unlock(desc, flags);
+}
+
+/**
* irq_get_irqchip_state - returns the irqchip state of a interrupt.
* @irq: Interrupt line that is forwarded to a VM
* @which: One of IRQCHIP_STATE_* the caller wants to know about