// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
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* Copyright (C) 2005-2006 Thomas Gleixner
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*
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* This file contains driver APIs to the irq subsystem.
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*/
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#define pr_fmt(fmt) "genirq: " fmt
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#include <linux/irq.h>
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#include <linux/kthread.h>
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#include <linux/module.h>
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#include <linux/random.h>
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#include <linux/interrupt.h>
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#include <linux/irqdomain.h>
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#include <linux/slab.h>
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#include <linux/sched.h>
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#include <linux/sched/rt.h>
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#include <linux/sched/task.h>
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#include <linux/sched/isolation.h>
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#include <uapi/linux/sched/types.h>
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#include <linux/task_work.h>
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#include "internals.h"
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#if defined(CONFIG_IRQ_FORCED_THREADING) && !defined(CONFIG_PREEMPT_RT)
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__read_mostly bool force_irqthreads;
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EXPORT_SYMBOL_GPL(force_irqthreads);
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static int __init setup_forced_irqthreads(char *arg)
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{
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force_irqthreads = true;
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return 0;
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}
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early_param("threadirqs", setup_forced_irqthreads);
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#endif
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static void __synchronize_hardirq(struct irq_desc *desc, bool sync_chip)
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{
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struct irq_data *irqd = irq_desc_get_irq_data(desc);
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bool inprogress;
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do {
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unsigned long flags;
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/*
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* Wait until we're out of the critical section. This might
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* give the wrong answer due to the lack of memory barriers.
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*/
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while (irqd_irq_inprogress(&desc->irq_data))
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cpu_relax();
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/* Ok, that indicated we're done: double-check carefully. */
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raw_spin_lock_irqsave(&desc->lock, flags);
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inprogress = irqd_irq_inprogress(&desc->irq_data);
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/*
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* If requested and supported, check at the chip whether it
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* is in flight at the hardware level, i.e. already pending
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* in a CPU and waiting for service and acknowledge.
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*/
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if (!inprogress && sync_chip) {
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/*
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* Ignore the return code. inprogress is only updated
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* when the chip supports it.
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*/
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__irq_get_irqchip_state(irqd, IRQCHIP_STATE_ACTIVE,
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&inprogress);
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}
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raw_spin_unlock_irqrestore(&desc->lock, flags);
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/* Oops, that failed? */
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} while (inprogress);
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}
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/**
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* synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
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* @irq: interrupt number to wait for
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*
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* This function waits for any pending hard IRQ handlers for this
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* interrupt to complete before returning. If you use this
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* function while holding a resource the IRQ handler may need you
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* will deadlock. It does not take associated threaded handlers
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* into account.
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*
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* Do not use this for shutdown scenarios where you must be sure
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* that all parts (hardirq and threaded handler) have completed.
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*
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* Returns: false if a threaded handler is active.
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*
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* This function may be called - with care - from IRQ context.
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*
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* It does not check whether there is an interrupt in flight at the
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* hardware level, but not serviced yet, as this might deadlock when
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* called with interrupts disabled and the target CPU of the interrupt
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* is the current CPU.
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*/
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bool synchronize_hardirq(unsigned int irq)
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{
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struct irq_desc *desc = irq_to_desc(irq);
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if (desc) {
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__synchronize_hardirq(desc, false);
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return !atomic_read(&desc->threads_active);
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}
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return true;
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}
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EXPORT_SYMBOL(synchronize_hardirq);
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/**
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* synchronize_irq - wait for pending IRQ handlers (on other CPUs)
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* @irq: interrupt number to wait for
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*
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* This function waits for any pending IRQ handlers for this interrupt
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* to complete before returning. If you use this function while
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* holding a resource the IRQ handler may need you will deadlock.
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*
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* Can only be called from preemptible code as it might sleep when
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* an interrupt thread is associated to @irq.
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*
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* It optionally makes sure (when the irq chip supports that method)
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* that the interrupt is not pending in any CPU and waiting for
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* service.
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*/
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void synchronize_irq(unsigned int irq)
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{
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struct irq_desc *desc = irq_to_desc(irq);
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if (desc) {
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__synchronize_hardirq(desc, true);
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/*
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* We made sure that no hardirq handler is
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* running. Now verify that no threaded handlers are
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* active.
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*/
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wait_event(desc->wait_for_threads,
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!atomic_read(&desc->threads_active));
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}
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}
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EXPORT_SYMBOL(synchronize_irq);
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#ifdef CONFIG_SMP
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cpumask_var_t irq_default_affinity;
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static bool __irq_can_set_affinity(struct irq_desc *desc)
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{
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if (!desc || !irqd_can_balance(&desc->irq_data) ||
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!desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
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return false;
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return true;
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}
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/**
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* irq_can_set_affinity - Check if the affinity of a given irq can be set
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* @irq: Interrupt to check
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*
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*/
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int irq_can_set_affinity(unsigned int irq)
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{
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return __irq_can_set_affinity(irq_to_desc(irq));
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}
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/**
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* irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
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* @irq: Interrupt to check
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*
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* Like irq_can_set_affinity() above, but additionally checks for the
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* AFFINITY_MANAGED flag.
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*/
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bool irq_can_set_affinity_usr(unsigned int irq)
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{
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struct irq_desc *desc = irq_to_desc(irq);
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return __irq_can_set_affinity(desc) &&
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!irqd_affinity_is_managed(&desc->irq_data);
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}
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/**
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* irq_set_thread_affinity - Notify irq threads to adjust affinity
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* @desc: irq descriptor which has affitnity changed
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*
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* We just set IRQTF_AFFINITY and delegate the affinity setting
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* to the interrupt thread itself. We can not call
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* set_cpus_allowed_ptr() here as we hold desc->lock and this
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* code can be called from hard interrupt context.
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*/
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void irq_set_thread_affinity(struct irq_desc *desc)
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{
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struct irqaction *action;
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for_each_action_of_desc(desc, action)
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if (action->thread)
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set_bit(IRQTF_AFFINITY, &action->thread_flags);
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}
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#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
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static void irq_validate_effective_affinity(struct irq_data *data)
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{
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const struct cpumask *m = irq_data_get_effective_affinity_mask(data);
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struct irq_chip *chip = irq_data_get_irq_chip(data);
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if (!cpumask_empty(m))
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return;
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pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",
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chip->name, data->irq);
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}
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static inline void irq_init_effective_affinity(struct irq_data *data,
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const struct cpumask *mask)
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{
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cpumask_copy(irq_data_get_effective_affinity_mask(data), mask);
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}
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#else
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static inline void irq_validate_effective_affinity(struct irq_data *data) { }
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static inline void irq_init_effective_affinity(struct irq_data *data,
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const struct cpumask *mask) { }
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#endif
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int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
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bool force)
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{
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struct irq_desc *desc = irq_data_to_desc(data);
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struct irq_chip *chip = irq_data_get_irq_chip(data);
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const struct cpumask *prog_mask;
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int ret;
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static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
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static struct cpumask tmp_mask;
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if (!chip || !chip->irq_set_affinity)
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return -EINVAL;
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raw_spin_lock(&tmp_mask_lock);
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/*
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* If this is a managed interrupt and housekeeping is enabled on
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* it check whether the requested affinity mask intersects with
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* a housekeeping CPU. If so, then remove the isolated CPUs from
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* the mask and just keep the housekeeping CPU(s). This prevents
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* the affinity setter from routing the interrupt to an isolated
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* CPU to avoid that I/O submitted from a housekeeping CPU causes
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* interrupts on an isolated one.
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*
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* If the masks do not intersect or include online CPU(s) then
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* keep the requested mask. The isolated target CPUs are only
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* receiving interrupts when the I/O operation was submitted
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* directly from them.
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*
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* If all housekeeping CPUs in the affinity mask are offline, the
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* interrupt will be migrated by the CPU hotplug code once a
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* housekeeping CPU which belongs to the affinity mask comes
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* online.
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*/
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if (irqd_affinity_is_managed(data) &&
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housekeeping_enabled(HK_FLAG_MANAGED_IRQ)) {
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const struct cpumask *hk_mask;
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hk_mask = housekeeping_cpumask(HK_FLAG_MANAGED_IRQ);
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cpumask_and(&tmp_mask, mask, hk_mask);
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if (!cpumask_intersects(&tmp_mask, cpu_online_mask))
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prog_mask = mask;
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else
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prog_mask = &tmp_mask;
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} else {
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prog_mask = mask;
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}
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/*
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* Make sure we only provide online CPUs to the irqchip,
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* unless we are being asked to force the affinity (in which
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* case we do as we are told).
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*/
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cpumask_and(&tmp_mask, prog_mask, cpu_online_mask);
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if (!force && !cpumask_empty(&tmp_mask))
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ret = chip->irq_set_affinity(data, &tmp_mask, force);
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else if (force)
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ret = chip->irq_set_affinity(data, mask, force);
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else
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ret = -EINVAL;
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raw_spin_unlock(&tmp_mask_lock);
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switch (ret) {
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case IRQ_SET_MASK_OK:
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case IRQ_SET_MASK_OK_DONE:
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cpumask_copy(desc->irq_common_data.affinity, mask);
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fallthrough;
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case IRQ_SET_MASK_OK_NOCOPY:
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irq_validate_effective_affinity(data);
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irq_set_thread_affinity(desc);
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ret = 0;
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}
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return ret;
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}
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EXPORT_SYMBOL_GPL(irq_do_set_affinity);
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#ifdef CONFIG_GENERIC_PENDING_IRQ
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static inline int irq_set_affinity_pending(struct irq_data *data,
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const struct cpumask *dest)
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{
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struct irq_desc *desc = irq_data_to_desc(data);
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irqd_set_move_pending(data);
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irq_copy_pending(desc, dest);
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return 0;
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}
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#else
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static inline int irq_set_affinity_pending(struct irq_data *data,
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const struct cpumask *dest)
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{
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return -EBUSY;
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}
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#endif
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static int irq_try_set_affinity(struct irq_data *data,
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const struct cpumask *dest, bool force)
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{
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int ret = irq_do_set_affinity(data, dest, force);
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/*
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* In case that the underlying vector management is busy and the
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* architecture supports the generic pending mechanism then utilize
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* this to avoid returning an error to user space.
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*/
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if (ret == -EBUSY && !force)
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ret = irq_set_affinity_pending(data, dest);
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return ret;
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}
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static bool irq_set_affinity_deactivated(struct irq_data *data,
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const struct cpumask *mask, bool force)
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{
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struct irq_desc *desc = irq_data_to_desc(data);
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/*
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* Handle irq chips which can handle affinity only in activated
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* state correctly
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*
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* If the interrupt is not yet activated, just store the affinity
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* mask and do not call the chip driver at all. On activation the
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* driver has to make sure anyway that the interrupt is in a
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* useable state so startup works.
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*/
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if (!IS_ENABLED(CONFIG_IRQ_DOMAIN_HIERARCHY) ||
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irqd_is_activated(data) || !irqd_affinity_on_activate(data))
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return false;
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cpumask_copy(desc->irq_common_data.affinity, mask);
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irq_init_effective_affinity(data, mask);
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irqd_set(data, IRQD_AFFINITY_SET);
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return true;
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}
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int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
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bool force)
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{
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struct irq_chip *chip = irq_data_get_irq_chip(data);
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struct irq_desc *desc = irq_data_to_desc(data);
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int ret = 0;
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if (!chip || !chip->irq_set_affinity)
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return -EINVAL;
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if (irq_set_affinity_deactivated(data, mask, force))
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return 0;
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if (irq_can_move_pcntxt(data) && !irqd_is_setaffinity_pending(data)) {
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ret = irq_try_set_affinity(data, mask, force);
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} else {
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irqd_set_move_pending(data);
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irq_copy_pending(desc, mask);
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}
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if (desc->affinity_notify) {
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kref_get(&desc->affinity_notify->kref);
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if (!schedule_work(&desc->affinity_notify->work)) {
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/* Work was already scheduled, drop our extra ref */
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kref_put(&desc->affinity_notify->kref,
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desc->affinity_notify->release);
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}
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}
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irqd_set(data, IRQD_AFFINITY_SET);
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return ret;
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}
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int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force)
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{
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struct irq_desc *desc = irq_to_desc(irq);
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unsigned long flags;
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int ret;
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if (!desc)
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return -EINVAL;
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raw_spin_lock_irqsave(&desc->lock, flags);
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ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
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raw_spin_unlock_irqrestore(&desc->lock, flags);
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return ret;
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}
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int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
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{
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unsigned long flags;
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struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
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if (!desc)
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return -EINVAL;
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desc->affinity_hint = m;
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irq_put_desc_unlock(desc, flags);
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/* set the initial affinity to prevent every interrupt being on CPU0 */
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if (m)
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__irq_set_affinity(irq, m, false);
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return 0;
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}
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EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
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static void irq_affinity_notify(struct work_struct *work)
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{
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struct irq_affinity_notify *notify =
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container_of(work, struct irq_affinity_notify, work);
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struct irq_desc *desc = irq_to_desc(notify->irq);
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cpumask_var_t cpumask;
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unsigned long flags;
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if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL))
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goto out;
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raw_spin_lock_irqsave(&desc->lock, flags);
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if (irq_move_pending(&desc->irq_data))
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irq_get_pending(cpumask, desc);
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else
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cpumask_copy(cpumask, desc->irq_common_data.affinity);
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raw_spin_unlock_irqrestore(&desc->lock, flags);
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notify->notify(notify, cpumask);
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free_cpumask_var(cpumask);
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out:
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kref_put(¬ify->kref, notify->release);
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}
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/**
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* irq_set_affinity_notifier - control notification of IRQ affinity changes
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* @irq: Interrupt for which to enable/disable notification
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* @notify: Context for notification, or %NULL to disable
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* notification. Function pointers must be initialised;
|
* the other fields will be initialised by this function.
|
*
|
* Must be called in process context. Notification may only be enabled
|
* after the IRQ is allocated and must be disabled before the IRQ is
|
* freed using free_irq().
|
*/
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int
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irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
|
{
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struct irq_desc *desc = irq_to_desc(irq);
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struct irq_affinity_notify *old_notify;
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unsigned long flags;
|
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/* The release function is promised process context */
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might_sleep();
|
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if (!desc || desc->istate & IRQS_NMI)
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return -EINVAL;
|
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/* Complete initialisation of *notify */
|
if (notify) {
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notify->irq = irq;
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kref_init(¬ify->kref);
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INIT_WORK(¬ify->work, irq_affinity_notify);
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}
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raw_spin_lock_irqsave(&desc->lock, flags);
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old_notify = desc->affinity_notify;
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desc->affinity_notify = notify;
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raw_spin_unlock_irqrestore(&desc->lock, flags);
|
|
if (old_notify) {
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if (cancel_work_sync(&old_notify->work)) {
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/* Pending work had a ref, put that one too */
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kref_put(&old_notify->kref, old_notify->release);
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}
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kref_put(&old_notify->kref, old_notify->release);
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}
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return 0;
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}
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EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
|
|
#ifndef CONFIG_AUTO_IRQ_AFFINITY
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/*
|
* Generic version of the affinity autoselector.
|
*/
|
int irq_setup_affinity(struct irq_desc *desc)
|
{
|
struct cpumask *set = irq_default_affinity;
|
int ret, node = irq_desc_get_node(desc);
|
static DEFINE_RAW_SPINLOCK(mask_lock);
|
static struct cpumask mask;
|
|
/* Excludes PER_CPU and NO_BALANCE interrupts */
|
if (!__irq_can_set_affinity(desc))
|
return 0;
|
|
raw_spin_lock(&mask_lock);
|
/*
|
* Preserve the managed affinity setting and a userspace affinity
|
* setup, but make sure that one of the targets is online.
|
*/
|
if (irqd_affinity_is_managed(&desc->irq_data) ||
|
irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
|
if (cpumask_intersects(desc->irq_common_data.affinity,
|
cpu_online_mask))
|
set = desc->irq_common_data.affinity;
|
else
|
irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
|
}
|
|
cpumask_and(&mask, cpu_online_mask, set);
|
if (cpumask_empty(&mask))
|
cpumask_copy(&mask, cpu_online_mask);
|
|
if (node != NUMA_NO_NODE) {
|
const struct cpumask *nodemask = cpumask_of_node(node);
|
|
/* make sure at least one of the cpus in nodemask is online */
|
if (cpumask_intersects(&mask, nodemask))
|
cpumask_and(&mask, &mask, nodemask);
|
}
|
ret = irq_do_set_affinity(&desc->irq_data, &mask, false);
|
raw_spin_unlock(&mask_lock);
|
return ret;
|
}
|
#else
|
/* Wrapper for ALPHA specific affinity selector magic */
|
int irq_setup_affinity(struct irq_desc *desc)
|
{
|
return irq_select_affinity(irq_desc_get_irq(desc));
|
}
|
#endif /* CONFIG_AUTO_IRQ_AFFINITY */
|
#endif /* CONFIG_SMP */
|
|
|
/**
|
* irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
|
* @irq: interrupt number to set affinity
|
* @vcpu_info: vCPU specific data or pointer to a percpu array of vCPU
|
* specific data for percpu_devid interrupts
|
*
|
* This function uses the vCPU specific data to set the vCPU
|
* affinity for an irq. The vCPU specific data is passed from
|
* outside, such as KVM. One example code path is as below:
|
* KVM -> IOMMU -> irq_set_vcpu_affinity().
|
*/
|
int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
|
{
|
unsigned long flags;
|
struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
|
struct irq_data *data;
|
struct irq_chip *chip;
|
int ret = -ENOSYS;
|
|
if (!desc)
|
return -EINVAL;
|
|
data = irq_desc_get_irq_data(desc);
|
do {
|
chip = irq_data_get_irq_chip(data);
|
if (chip && chip->irq_set_vcpu_affinity)
|
break;
|
#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
|
data = data->parent_data;
|
#else
|
data = NULL;
|
#endif
|
} while (data);
|
|
if (data)
|
ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
|
irq_put_desc_unlock(desc, flags);
|
|
return ret;
|
}
|
EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
|
|
void __disable_irq(struct irq_desc *desc)
|
{
|
if (!desc->depth++)
|
irq_disable(desc);
|
}
|
|
static int __disable_irq_nosync(unsigned int irq)
|
{
|
unsigned long flags;
|
struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
|
|
if (!desc)
|
return -EINVAL;
|
__disable_irq(desc);
|
irq_put_desc_busunlock(desc, flags);
|
return 0;
|
}
|
|
/**
|
* disable_irq_nosync - disable an irq without waiting
|
* @irq: Interrupt to disable
|
*
|
* Disable the selected interrupt line. Disables and Enables are
|
* nested.
|
* Unlike disable_irq(), this function does not ensure existing
|
* instances of the IRQ handler have completed before returning.
|
*
|
* This function may be called from IRQ context.
|
*/
|
void disable_irq_nosync(unsigned int irq)
|
{
|
__disable_irq_nosync(irq);
|
}
|
EXPORT_SYMBOL(disable_irq_nosync);
|
|
/**
|
* disable_irq - disable an irq and wait for completion
|
* @irq: Interrupt to disable
|
*
|
* Disable the selected interrupt line. Enables and Disables are
|
* nested.
|
* This function waits for any pending IRQ handlers for this interrupt
|
* to complete before returning. If you use this function while
|
* holding a resource the IRQ handler may need you will deadlock.
|
*
|
* This function may be called - with care - from IRQ context.
|
*/
|
void disable_irq(unsigned int irq)
|
{
|
if (!__disable_irq_nosync(irq))
|
synchronize_irq(irq);
|
}
|
EXPORT_SYMBOL(disable_irq);
|
|
/**
|
* disable_hardirq - disables an irq and waits for hardirq completion
|
* @irq: Interrupt to disable
|
*
|
* Disable the selected interrupt line. Enables and Disables are
|
* nested.
|
* This function waits for any pending hard IRQ handlers for this
|
* interrupt to complete before returning. If you use this function while
|
* holding a resource the hard IRQ handler may need you will deadlock.
|
*
|
* When used to optimistically disable an interrupt from atomic context
|
* the return value must be checked.
|
*
|
* Returns: false if a threaded handler is active.
|
*
|
* This function may be called - with care - from IRQ context.
|
*/
|
bool disable_hardirq(unsigned int irq)
|
{
|
if (!__disable_irq_nosync(irq))
|
return synchronize_hardirq(irq);
|
|
return false;
|
}
|
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) {
|
case 0:
|
err_out:
|
WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",
|
irq_desc_get_irq(desc));
|
break;
|
case 1: {
|
if (desc->istate & IRQS_SUSPENDED)
|
goto err_out;
|
/* Prevent probing on this irq: */
|
irq_settings_set_noprobe(desc);
|
/*
|
* Call irq_startup() not irq_enable() here because the
|
* interrupt might be marked NOAUTOEN. So irq_startup()
|
* needs to be invoked when it gets enabled the first
|
* time. If it was already started up, then irq_startup()
|
* will invoke irq_enable() under the hood.
|
*/
|
irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE);
|
break;
|
}
|
default:
|
desc->depth--;
|
}
|
}
|
|
/**
|
* enable_irq - enable handling of an irq
|
* @irq: Interrupt to enable
|
*
|
* Undoes the effect of one call to disable_irq(). If this
|
* matches the last disable, processing of interrupts on this
|
* IRQ line is re-enabled.
|
*
|
* This function may be called from IRQ context only when
|
* desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
|
*/
|
void enable_irq(unsigned int irq)
|
{
|
unsigned long flags;
|
struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
|
|
if (!desc)
|
return;
|
if (WARN(!desc->irq_data.chip,
|
KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
|
goto out;
|
|
__enable_irq(desc);
|
out:
|
irq_put_desc_busunlock(desc, flags);
|
}
|
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);
|
int ret = -ENXIO;
|
|
if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
|
return 0;
|
|
if (desc->irq_data.chip->irq_set_wake)
|
ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
|
|
return ret;
|
}
|
|
/**
|
* irq_set_irq_wake - control irq power management wakeup
|
* @irq: interrupt to control
|
* @on: enable/disable power management wakeup
|
*
|
* Enable/disable power management wakeup mode, which is
|
* disabled by default. Enables and disables must match,
|
* just as they match for non-wakeup mode support.
|
*
|
* Wakeup mode lets this IRQ wake the system from sleep
|
* states like "suspend to RAM".
|
*
|
* Note: irq enable/disable state is completely orthogonal
|
* to the enable/disable state of irq wake. An irq can be
|
* disabled with disable_irq() and still wake the system as
|
* long as the irq has wake enabled. If this does not hold,
|
* then the underlying irq chip and the related driver need
|
* to be investigated.
|
*/
|
int irq_set_irq_wake(unsigned int irq, unsigned int on)
|
{
|
unsigned long flags;
|
struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
|
int ret = 0;
|
|
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.
|
*/
|
if (on) {
|
if (desc->wake_depth++ == 0) {
|
ret = set_irq_wake_real(irq, on);
|
if (ret)
|
desc->wake_depth = 0;
|
else
|
irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
|
}
|
} else {
|
if (desc->wake_depth == 0) {
|
WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
|
} else if (--desc->wake_depth == 0) {
|
ret = set_irq_wake_real(irq, on);
|
if (ret)
|
desc->wake_depth = 1;
|
else
|
irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
|
}
|
}
|
|
out_unlock:
|
irq_put_desc_busunlock(desc, flags);
|
return ret;
|
}
|
EXPORT_SYMBOL(irq_set_irq_wake);
|
|
/*
|
* Internal function that tells the architecture code whether a
|
* particular irq has been exclusively allocated or is available
|
* for driver use.
|
*/
|
int can_request_irq(unsigned int irq, unsigned long irqflags)
|
{
|
unsigned long flags;
|
struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
|
int canrequest = 0;
|
|
if (!desc)
|
return 0;
|
|
if (irq_settings_can_request(desc)) {
|
if (!desc->action ||
|
irqflags & desc->action->flags & IRQF_SHARED)
|
canrequest = 1;
|
}
|
irq_put_desc_unlock(desc, flags);
|
return canrequest;
|
}
|
|
int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
|
{
|
struct irq_chip *chip = desc->irq_data.chip;
|
int ret, unmask = 0;
|
|
if (!chip || !chip->irq_set_type) {
|
/*
|
* IRQF_TRIGGER_* but the PIC does not support multiple
|
* flow-types?
|
*/
|
pr_debug("No set_type function for IRQ %d (%s)\n",
|
irq_desc_get_irq(desc),
|
chip ? (chip->name ? : "unknown") : "unknown");
|
return 0;
|
}
|
|
if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
|
if (!irqd_irq_masked(&desc->irq_data))
|
mask_irq(desc);
|
if (!irqd_irq_disabled(&desc->irq_data))
|
unmask = 1;
|
}
|
|
/* Mask all flags except trigger mode */
|
flags &= IRQ_TYPE_SENSE_MASK;
|
ret = chip->irq_set_type(&desc->irq_data, flags);
|
|
switch (ret) {
|
case IRQ_SET_MASK_OK:
|
case IRQ_SET_MASK_OK_DONE:
|
irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
|
irqd_set(&desc->irq_data, flags);
|
fallthrough;
|
|
case IRQ_SET_MASK_OK_NOCOPY:
|
flags = irqd_get_trigger_type(&desc->irq_data);
|
irq_settings_set_trigger_mask(desc, flags);
|
irqd_clear(&desc->irq_data, IRQD_LEVEL);
|
irq_settings_clr_level(desc);
|
if (flags & IRQ_TYPE_LEVEL_MASK) {
|
irq_settings_set_level(desc);
|
irqd_set(&desc->irq_data, IRQD_LEVEL);
|
}
|
|
ret = 0;
|
break;
|
default:
|
pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",
|
flags, irq_desc_get_irq(desc), chip->irq_set_type);
|
}
|
if (unmask)
|
unmask_irq(desc);
|
return ret;
|
}
|
|
#ifdef CONFIG_HARDIRQS_SW_RESEND
|
int irq_set_parent(int irq, int parent_irq)
|
{
|
unsigned long flags;
|
struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
|
|
if (!desc)
|
return -EINVAL;
|
|
desc->parent_irq = parent_irq;
|
|
irq_put_desc_unlock(desc, flags);
|
return 0;
|
}
|
EXPORT_SYMBOL_GPL(irq_set_parent);
|
#endif
|
|
/*
|
* Default primary interrupt handler for threaded interrupts. Is
|
* assigned as primary handler when request_threaded_irq is called
|
* with handler == NULL. Useful for oneshot interrupts.
|
*/
|
static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
|
{
|
return IRQ_WAKE_THREAD;
|
}
|
|
/*
|
* Primary handler for nested threaded interrupts. Should never be
|
* called.
|
*/
|
static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
|
{
|
WARN(1, "Primary handler called for nested irq %d\n", irq);
|
return IRQ_NONE;
|
}
|
|
static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
|
{
|
WARN(1, "Secondary action handler called for irq %d\n", irq);
|
return IRQ_NONE;
|
}
|
|
static int irq_wait_for_interrupt(struct irqaction *action)
|
{
|
for (;;) {
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
if (kthread_should_stop()) {
|
/* may need to run one last time */
|
if (test_and_clear_bit(IRQTF_RUNTHREAD,
|
&action->thread_flags)) {
|
__set_current_state(TASK_RUNNING);
|
return 0;
|
}
|
__set_current_state(TASK_RUNNING);
|
return -1;
|
}
|
|
if (test_and_clear_bit(IRQTF_RUNTHREAD,
|
&action->thread_flags)) {
|
__set_current_state(TASK_RUNNING);
|
return 0;
|
}
|
schedule();
|
}
|
}
|
|
/*
|
* Oneshot interrupts keep the irq line masked until the threaded
|
* handler finished. unmask if the interrupt has not been disabled and
|
* is marked MASKED.
|
*/
|
static void irq_finalize_oneshot(struct irq_desc *desc,
|
struct irqaction *action)
|
{
|
if (!(desc->istate & IRQS_ONESHOT) ||
|
action->handler == irq_forced_secondary_handler)
|
return;
|
again:
|
chip_bus_lock(desc);
|
raw_spin_lock_irq(&desc->lock);
|
|
/*
|
* Implausible though it may be we need to protect us against
|
* the following scenario:
|
*
|
* The thread is faster done than the hard interrupt handler
|
* on the other CPU. If we unmask the irq line then the
|
* interrupt can come in again and masks the line, leaves due
|
* to IRQS_INPROGRESS and the irq line is masked forever.
|
*
|
* This also serializes the state of shared oneshot handlers
|
* versus "desc->threads_onehsot |= action->thread_mask;" in
|
* irq_wake_thread(). See the comment there which explains the
|
* serialization.
|
*/
|
if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
|
raw_spin_unlock_irq(&desc->lock);
|
chip_bus_sync_unlock(desc);
|
cpu_relax();
|
goto again;
|
}
|
|
/*
|
* Now check again, whether the thread should run. Otherwise
|
* we would clear the threads_oneshot bit of this thread which
|
* was just set.
|
*/
|
if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
|
goto out_unlock;
|
|
desc->threads_oneshot &= ~action->thread_mask;
|
|
if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
|
irqd_irq_masked(&desc->irq_data))
|
unmask_threaded_irq(desc);
|
|
out_unlock:
|
raw_spin_unlock_irq(&desc->lock);
|
chip_bus_sync_unlock(desc);
|
}
|
|
#ifdef CONFIG_SMP
|
/*
|
* Check whether we need to change the affinity of the interrupt thread.
|
*/
|
static void
|
irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
|
{
|
cpumask_var_t mask;
|
bool valid = true;
|
|
if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
|
return;
|
|
/*
|
* In case we are out of memory we set IRQTF_AFFINITY again and
|
* try again next time
|
*/
|
if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
|
set_bit(IRQTF_AFFINITY, &action->thread_flags);
|
return;
|
}
|
|
raw_spin_lock_irq(&desc->lock);
|
/*
|
* This code is triggered unconditionally. Check the affinity
|
* mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
|
*/
|
if (cpumask_available(desc->irq_common_data.affinity)) {
|
const struct cpumask *m;
|
|
m = irq_data_get_effective_affinity_mask(&desc->irq_data);
|
cpumask_copy(mask, m);
|
} else {
|
valid = false;
|
}
|
raw_spin_unlock_irq(&desc->lock);
|
|
if (valid)
|
set_cpus_allowed_ptr(current, mask);
|
free_cpumask_var(mask);
|
}
|
#else
|
static inline void
|
irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
|
#endif
|
|
/*
|
* Interrupts which are not explicitly requested as threaded
|
* interrupts rely on the implicit bh/preempt disable of the hard irq
|
* context. So we need to disable bh here to avoid deadlocks and other
|
* side effects.
|
*/
|
static irqreturn_t
|
irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
|
{
|
irqreturn_t ret;
|
|
local_bh_disable();
|
if (!IS_ENABLED(CONFIG_PREEMPT_RT))
|
local_irq_disable();
|
ret = action->thread_fn(action->irq, action->dev_id);
|
if (ret == IRQ_HANDLED)
|
atomic_inc(&desc->threads_handled);
|
|
irq_finalize_oneshot(desc, action);
|
if (!IS_ENABLED(CONFIG_PREEMPT_RT))
|
local_irq_enable();
|
local_bh_enable();
|
return ret;
|
}
|
|
/*
|
* Interrupts explicitly requested as threaded interrupts want to be
|
* preemtible - many of them need to sleep and wait for slow busses to
|
* complete.
|
*/
|
static irqreturn_t irq_thread_fn(struct irq_desc *desc,
|
struct irqaction *action)
|
{
|
irqreturn_t ret;
|
|
ret = action->thread_fn(action->irq, action->dev_id);
|
if (ret == IRQ_HANDLED)
|
atomic_inc(&desc->threads_handled);
|
|
irq_finalize_oneshot(desc, action);
|
return ret;
|
}
|
|
static void wake_threads_waitq(struct irq_desc *desc)
|
{
|
if (atomic_dec_and_test(&desc->threads_active))
|
wake_up(&desc->wait_for_threads);
|
}
|
|
static void irq_thread_dtor(struct callback_head *unused)
|
{
|
struct task_struct *tsk = current;
|
struct irq_desc *desc;
|
struct irqaction *action;
|
|
if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
|
return;
|
|
action = kthread_data(tsk);
|
|
pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
|
tsk->comm, tsk->pid, action->irq);
|
|
|
desc = irq_to_desc(action->irq);
|
/*
|
* If IRQTF_RUNTHREAD is set, we need to decrement
|
* desc->threads_active and wake possible waiters.
|
*/
|
if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
|
wake_threads_waitq(desc);
|
|
/* Prevent a stale desc->threads_oneshot */
|
irq_finalize_oneshot(desc, action);
|
}
|
|
static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
|
{
|
struct irqaction *secondary = action->secondary;
|
|
if (WARN_ON_ONCE(!secondary))
|
return;
|
|
raw_spin_lock_irq(&desc->lock);
|
__irq_wake_thread(desc, secondary);
|
raw_spin_unlock_irq(&desc->lock);
|
}
|
|
/*
|
* Internal function to notify that a interrupt thread is ready.
|
*/
|
static void irq_thread_set_ready(struct irq_desc *desc,
|
struct irqaction *action)
|
{
|
set_bit(IRQTF_READY, &action->thread_flags);
|
wake_up(&desc->wait_for_threads);
|
}
|
|
/*
|
* Internal function to wake up a interrupt thread and wait until it is
|
* ready.
|
*/
|
static void wake_up_and_wait_for_irq_thread_ready(struct irq_desc *desc,
|
struct irqaction *action)
|
{
|
if (!action || !action->thread)
|
return;
|
|
wake_up_process(action->thread);
|
wait_event(desc->wait_for_threads,
|
test_bit(IRQTF_READY, &action->thread_flags));
|
}
|
|
/*
|
* Interrupt handler thread
|
*/
|
static int irq_thread(void *data)
|
{
|
struct callback_head on_exit_work;
|
struct irqaction *action = data;
|
struct irq_desc *desc = irq_to_desc(action->irq);
|
irqreturn_t (*handler_fn)(struct irq_desc *desc,
|
struct irqaction *action);
|
|
irq_thread_set_ready(desc, action);
|
|
sched_set_fifo(current);
|
|
if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
|
&action->thread_flags))
|
handler_fn = irq_forced_thread_fn;
|
else
|
handler_fn = irq_thread_fn;
|
|
init_task_work(&on_exit_work, irq_thread_dtor);
|
task_work_add(current, &on_exit_work, TWA_NONE);
|
|
irq_thread_check_affinity(desc, action);
|
|
while (!irq_wait_for_interrupt(action)) {
|
irqreturn_t action_ret;
|
|
irq_thread_check_affinity(desc, action);
|
|
action_ret = handler_fn(desc, action);
|
if (action_ret == IRQ_WAKE_THREAD)
|
irq_wake_secondary(desc, action);
|
|
wake_threads_waitq(desc);
|
}
|
|
/*
|
* This is the regular exit path. __free_irq() is stopping the
|
* thread via kthread_stop() after calling
|
* synchronize_hardirq(). So neither IRQTF_RUNTHREAD nor the
|
* oneshot mask bit can be set.
|
*/
|
task_work_cancel(current, irq_thread_dtor);
|
return 0;
|
}
|
|
/**
|
* irq_wake_thread - wake the irq thread for the action identified by dev_id
|
* @irq: Interrupt line
|
* @dev_id: Device identity for which the thread should be woken
|
*
|
*/
|
void irq_wake_thread(unsigned int irq, void *dev_id)
|
{
|
struct irq_desc *desc = irq_to_desc(irq);
|
struct irqaction *action;
|
unsigned long flags;
|
|
if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
|
return;
|
|
raw_spin_lock_irqsave(&desc->lock, flags);
|
for_each_action_of_desc(desc, action) {
|
if (action->dev_id == dev_id) {
|
if (action->thread)
|
__irq_wake_thread(desc, action);
|
break;
|
}
|
}
|
raw_spin_unlock_irqrestore(&desc->lock, flags);
|
}
|
EXPORT_SYMBOL_GPL(irq_wake_thread);
|
|
static int irq_setup_forced_threading(struct irqaction *new)
|
{
|
if (!force_irqthreads)
|
return 0;
|
if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
|
return 0;
|
|
/*
|
* No further action required for interrupts which are requested as
|
* threaded interrupts already
|
*/
|
if (new->handler == irq_default_primary_handler)
|
return 0;
|
|
new->flags |= IRQF_ONESHOT;
|
|
/*
|
* Handle the case where we have a real primary handler and a
|
* thread handler. We force thread them as well by creating a
|
* secondary action.
|
*/
|
if (new->handler && new->thread_fn) {
|
/* Allocate the secondary action */
|
new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
|
if (!new->secondary)
|
return -ENOMEM;
|
new->secondary->handler = irq_forced_secondary_handler;
|
new->secondary->thread_fn = new->thread_fn;
|
new->secondary->dev_id = new->dev_id;
|
new->secondary->irq = new->irq;
|
new->secondary->name = new->name;
|
}
|
/* Deal with the primary handler */
|
set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
|
new->thread_fn = new->handler;
|
new->handler = irq_default_primary_handler;
|
return 0;
|
}
|
|
static int irq_request_resources(struct irq_desc *desc)
|
{
|
struct irq_data *d = &desc->irq_data;
|
struct irq_chip *c = d->chip;
|
|
return c->irq_request_resources ? c->irq_request_resources(d) : 0;
|
}
|
|
static void irq_release_resources(struct irq_desc *desc)
|
{
|
struct irq_data *d = &desc->irq_data;
|
struct irq_chip *c = d->chip;
|
|
if (c->irq_release_resources)
|
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)
|
{
|
struct task_struct *t;
|
|
if (!secondary) {
|
t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
|
new->name);
|
} else {
|
t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
|
new->name);
|
}
|
|
if (IS_ERR(t))
|
return PTR_ERR(t);
|
|
/*
|
* We keep the reference to the task struct even if
|
* the thread dies to avoid that the interrupt code
|
* references an already freed task_struct.
|
*/
|
new->thread = get_task_struct(t);
|
/*
|
* Tell the thread to set its affinity. This is
|
* important for shared interrupt handlers as we do
|
* not invoke setup_affinity() for the secondary
|
* handlers as everything is already set up. Even for
|
* interrupts marked with IRQF_NO_BALANCE this is
|
* correct as we want the thread to move to the cpu(s)
|
* on which the requesting code placed the interrupt.
|
*/
|
set_bit(IRQTF_AFFINITY, &new->thread_flags);
|
return 0;
|
}
|
|
/*
|
* Internal function to register an irqaction - typically used to
|
* allocate special interrupts that are part of the architecture.
|
*
|
* Locking rules:
|
*
|
* desc->request_mutex Provides serialization against a concurrent free_irq()
|
* chip_bus_lock Provides serialization for slow bus operations
|
* desc->lock Provides serialization against hard interrupts
|
*
|
* chip_bus_lock and desc->lock are sufficient for all other management and
|
* interrupt related functions. desc->request_mutex solely serializes
|
* request/free_irq().
|
*/
|
static int
|
__setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
|
{
|
struct irqaction *old, **old_ptr;
|
unsigned long flags, thread_mask = 0;
|
int ret, nested, shared = 0;
|
|
if (!desc)
|
return -EINVAL;
|
|
if (desc->irq_data.chip == &no_irq_chip)
|
return -ENOSYS;
|
if (!try_module_get(desc->owner))
|
return -ENODEV;
|
|
new->irq = irq;
|
|
/*
|
* If the trigger type is not specified by the caller,
|
* then use the default for this interrupt.
|
*/
|
if (!(new->flags & IRQF_TRIGGER_MASK))
|
new->flags |= irqd_get_trigger_type(&desc->irq_data);
|
|
/*
|
* Check whether the interrupt nests into another interrupt
|
* thread.
|
*/
|
nested = irq_settings_is_nested_thread(desc);
|
if (nested) {
|
if (!new->thread_fn) {
|
ret = -EINVAL;
|
goto out_mput;
|
}
|
/*
|
* Replace the primary handler which was provided from
|
* the driver for non nested interrupt handling by the
|
* dummy function which warns when called.
|
*/
|
new->handler = irq_nested_primary_handler;
|
} else {
|
if (irq_settings_can_thread(desc)) {
|
ret = irq_setup_forced_threading(new);
|
if (ret)
|
goto out_mput;
|
}
|
}
|
|
/*
|
* Create a handler thread when a thread function is supplied
|
* and the interrupt does not nest into another interrupt
|
* thread.
|
*/
|
if (new->thread_fn && !nested) {
|
ret = setup_irq_thread(new, irq, false);
|
if (ret)
|
goto out_mput;
|
if (new->secondary) {
|
ret = setup_irq_thread(new->secondary, irq, true);
|
if (ret)
|
goto out_thread;
|
}
|
}
|
|
/*
|
* Drivers are often written to work w/o knowledge about the
|
* underlying irq chip implementation, so a request for a
|
* threaded irq without a primary hard irq context handler
|
* requires the ONESHOT flag to be set. Some irq chips like
|
* MSI based interrupts are per se one shot safe. Check the
|
* chip flags, so we can avoid the unmask dance at the end of
|
* the threaded handler for those.
|
*/
|
if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
|
new->flags &= ~IRQF_ONESHOT;
|
|
/*
|
* Protects against a concurrent __free_irq() call which might wait
|
* for synchronize_hardirq() to complete without holding the optional
|
* chip bus lock and desc->lock. Also protects against handing out
|
* a recycled oneshot thread_mask bit while it's still in use by
|
* its previous owner.
|
*/
|
mutex_lock(&desc->request_mutex);
|
|
/*
|
* Acquire bus lock as the irq_request_resources() callback below
|
* might rely on the serialization or the magic power management
|
* functions which are abusing the irq_bus_lock() callback,
|
*/
|
chip_bus_lock(desc);
|
|
/* First installed action requests resources. */
|
if (!desc->action) {
|
ret = irq_request_resources(desc);
|
if (ret) {
|
pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
|
new->name, irq, desc->irq_data.chip->name);
|
goto out_bus_unlock;
|
}
|
}
|
|
/*
|
* The following block of code has to be executed atomically
|
* protected against a concurrent interrupt and any of the other
|
* management calls which are not serialized via
|
* desc->request_mutex or the optional bus lock.
|
*/
|
raw_spin_lock_irqsave(&desc->lock, flags);
|
old_ptr = &desc->action;
|
old = *old_ptr;
|
if (old) {
|
/*
|
* Can't share interrupts unless both agree to and are
|
* the same type (level, edge, polarity). So both flag
|
* 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.
|
*/
|
if (irqd_trigger_type_was_set(&desc->irq_data)) {
|
oldtype = irqd_get_trigger_type(&desc->irq_data);
|
} else {
|
oldtype = new->flags & IRQF_TRIGGER_MASK;
|
irqd_set_trigger_type(&desc->irq_data, oldtype);
|
}
|
|
if (!((old->flags & new->flags) & IRQF_SHARED) ||
|
(oldtype != (new->flags & IRQF_TRIGGER_MASK)) ||
|
((old->flags ^ new->flags) & IRQF_ONESHOT))
|
goto mismatch;
|
|
/* All handlers must agree on per-cpuness */
|
if ((old->flags & IRQF_PERCPU) !=
|
(new->flags & IRQF_PERCPU))
|
goto mismatch;
|
|
/* add new interrupt at end of irq queue */
|
do {
|
/*
|
* Or all existing action->thread_mask bits,
|
* so we can find the next zero bit for this
|
* new action.
|
*/
|
thread_mask |= old->thread_mask;
|
old_ptr = &old->next;
|
old = *old_ptr;
|
} while (old);
|
shared = 1;
|
}
|
|
/*
|
* Setup the thread mask for this irqaction for ONESHOT. For
|
* !ONESHOT irqs the thread mask is 0 so we can avoid a
|
* conditional in irq_wake_thread().
|
*/
|
if (new->flags & IRQF_ONESHOT) {
|
/*
|
* Unlikely to have 32 resp 64 irqs sharing one line,
|
* but who knows.
|
*/
|
if (thread_mask == ~0UL) {
|
ret = -EBUSY;
|
goto out_unlock;
|
}
|
/*
|
* The thread_mask for the action is or'ed to
|
* desc->thread_active to indicate that the
|
* IRQF_ONESHOT thread handler has been woken, but not
|
* yet finished. The bit is cleared when a thread
|
* completes. When all threads of a shared interrupt
|
* line have completed desc->threads_active becomes
|
* zero and the interrupt line is unmasked. See
|
* handle.c:irq_wake_thread() for further information.
|
*
|
* If no thread is woken by primary (hard irq context)
|
* interrupt handlers, then desc->threads_active is
|
* also checked for zero to unmask the irq line in the
|
* affected hard irq flow handlers
|
* (handle_[fasteoi|level]_irq).
|
*
|
* The new action gets the first zero bit of
|
* thread_mask assigned. See the loop above which or's
|
* all existing action->thread_mask bits.
|
*/
|
new->thread_mask = 1UL << ffz(thread_mask);
|
|
} else if (new->handler == irq_default_primary_handler &&
|
!(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
|
/*
|
* The interrupt was requested with handler = NULL, so
|
* we use the default primary handler for it. But it
|
* does not have the oneshot flag set. In combination
|
* with level interrupts this is deadly, because the
|
* default primary handler just wakes the thread, then
|
* the irq lines is reenabled, but the device still
|
* has the level irq asserted. Rinse and repeat....
|
*
|
* While this works for edge type interrupts, we play
|
* it safe and reject unconditionally because we can't
|
* say for sure which type this interrupt really
|
* has. The type flags are unreliable as the
|
* underlying chip implementation can override them.
|
*/
|
pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
|
new->name, irq);
|
ret = -EINVAL;
|
goto out_unlock;
|
}
|
|
if (!shared) {
|
/* Setup the type (level, edge polarity) if configured: */
|
if (new->flags & IRQF_TRIGGER_MASK) {
|
ret = __irq_set_trigger(desc,
|
new->flags & IRQF_TRIGGER_MASK);
|
|
if (ret)
|
goto out_unlock;
|
}
|
|
/*
|
* Activate the interrupt. That activation must happen
|
* independently of IRQ_NOAUTOEN. request_irq() can fail
|
* and the callers are supposed to handle
|
* that. enable_irq() of an interrupt requested with
|
* IRQ_NOAUTOEN is not supposed to fail. The activation
|
* keeps it in shutdown mode, it merily associates
|
* resources if necessary and if that's not possible it
|
* fails. Interrupts which are in managed shutdown mode
|
* will simply ignore that activation request.
|
*/
|
ret = irq_activate(desc);
|
if (ret)
|
goto out_unlock;
|
|
desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
|
IRQS_ONESHOT | IRQS_WAITING);
|
irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
|
|
if (new->flags & IRQF_PERCPU) {
|
irqd_set(&desc->irq_data, IRQD_PER_CPU);
|
irq_settings_set_per_cpu(desc);
|
}
|
|
if (new->flags & IRQF_ONESHOT)
|
desc->istate |= IRQS_ONESHOT;
|
|
/* Exclude IRQ from balancing if requested */
|
if (new->flags & IRQF_NOBALANCING) {
|
irq_settings_set_no_balancing(desc);
|
irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
|
}
|
|
if (irq_settings_can_autoenable(desc)) {
|
irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
|
} else {
|
/*
|
* Shared interrupts do not go well with disabling
|
* auto enable. The sharing interrupt might request
|
* it while it's still disabled and then wait for
|
* interrupts forever.
|
*/
|
WARN_ON_ONCE(new->flags & IRQF_SHARED);
|
/* Undo nested disables: */
|
desc->depth = 1;
|
}
|
|
} else if (new->flags & IRQF_TRIGGER_MASK) {
|
unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
|
unsigned int omsk = irqd_get_trigger_type(&desc->irq_data);
|
|
if (nmsk != omsk)
|
/* hope the handler works with current trigger mode */
|
pr_warn("irq %d uses trigger mode %u; requested %u\n",
|
irq, omsk, nmsk);
|
}
|
|
*old_ptr = new;
|
|
irq_pm_install_action(desc, new);
|
|
/* Reset broken irq detection when installing new handler */
|
desc->irq_count = 0;
|
desc->irqs_unhandled = 0;
|
|
/*
|
* Check whether we disabled the irq via the spurious handler
|
* before. Reenable it and give it another chance.
|
*/
|
if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
|
desc->istate &= ~IRQS_SPURIOUS_DISABLED;
|
__enable_irq(desc);
|
}
|
|
raw_spin_unlock_irqrestore(&desc->lock, flags);
|
chip_bus_sync_unlock(desc);
|
mutex_unlock(&desc->request_mutex);
|
|
irq_setup_timings(desc, new);
|
|
wake_up_and_wait_for_irq_thread_ready(desc, new);
|
wake_up_and_wait_for_irq_thread_ready(desc, new->secondary);
|
|
register_irq_proc(irq, desc);
|
new->dir = NULL;
|
register_handler_proc(irq, new);
|
return 0;
|
|
mismatch:
|
if (!(new->flags & IRQF_PROBE_SHARED)) {
|
pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
|
irq, new->flags, new->name, old->flags, old->name);
|
#ifdef CONFIG_DEBUG_SHIRQ
|
dump_stack();
|
#endif
|
}
|
ret = -EBUSY;
|
|
out_unlock:
|
raw_spin_unlock_irqrestore(&desc->lock, flags);
|
|
if (!desc->action)
|
irq_release_resources(desc);
|
out_bus_unlock:
|
chip_bus_sync_unlock(desc);
|
mutex_unlock(&desc->request_mutex);
|
|
out_thread:
|
if (new->thread) {
|
struct task_struct *t = new->thread;
|
|
new->thread = NULL;
|
kthread_stop(t);
|
put_task_struct(t);
|
}
|
if (new->secondary && new->secondary->thread) {
|
struct task_struct *t = new->secondary->thread;
|
|
new->secondary->thread = NULL;
|
kthread_stop(t);
|
put_task_struct(t);
|
}
|
out_mput:
|
module_put(desc->owner);
|
return ret;
|
}
|
|
/*
|
* Internal function to unregister an irqaction - used to free
|
* regular and special interrupts that are part of the architecture.
|
*/
|
static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
|
{
|
unsigned irq = desc->irq_data.irq;
|
struct irqaction *action, **action_ptr;
|
unsigned long flags;
|
|
WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
|
|
mutex_lock(&desc->request_mutex);
|
chip_bus_lock(desc);
|
raw_spin_lock_irqsave(&desc->lock, flags);
|
|
/*
|
* There can be multiple actions per IRQ descriptor, find the right
|
* one based on the dev_id:
|
*/
|
action_ptr = &desc->action;
|
for (;;) {
|
action = *action_ptr;
|
|
if (!action) {
|
WARN(1, "Trying to free already-free IRQ %d\n", irq);
|
raw_spin_unlock_irqrestore(&desc->lock, flags);
|
chip_bus_sync_unlock(desc);
|
mutex_unlock(&desc->request_mutex);
|
return NULL;
|
}
|
|
if (action->dev_id == dev_id)
|
break;
|
action_ptr = &action->next;
|
}
|
|
/* Found it - now remove it from the list of entries: */
|
*action_ptr = action->next;
|
|
irq_pm_remove_action(desc, action);
|
|
/* If this was the last handler, shut down the IRQ line: */
|
if (!desc->action) {
|
irq_settings_clr_disable_unlazy(desc);
|
/* Only shutdown. Deactivate after synchronize_hardirq() */
|
irq_shutdown(desc);
|
}
|
|
#ifdef CONFIG_SMP
|
/* make sure affinity_hint is cleaned up */
|
if (WARN_ON_ONCE(desc->affinity_hint))
|
desc->affinity_hint = NULL;
|
#endif
|
|
raw_spin_unlock_irqrestore(&desc->lock, flags);
|
/*
|
* Drop bus_lock here so the changes which were done in the chip
|
* callbacks above are synced out to the irq chips which hang
|
* behind a slow bus (I2C, SPI) before calling synchronize_hardirq().
|
*
|
* Aside of that the bus_lock can also be taken from the threaded
|
* handler in irq_finalize_oneshot() which results in a deadlock
|
* because kthread_stop() would wait forever for the thread to
|
* complete, which is blocked on the bus lock.
|
*
|
* The still held desc->request_mutex() protects against a
|
* concurrent request_irq() of this irq so the release of resources
|
* and timing data is properly serialized.
|
*/
|
chip_bus_sync_unlock(desc);
|
|
unregister_handler_proc(irq, action);
|
|
/*
|
* Make sure it's not being used on another CPU and if the chip
|
* supports it also make sure that there is no (not yet serviced)
|
* interrupt in flight at the hardware level.
|
*/
|
__synchronize_hardirq(desc, true);
|
|
#ifdef CONFIG_DEBUG_SHIRQ
|
/*
|
* It's a shared IRQ -- the driver ought to be prepared for an IRQ
|
* event to happen even now it's being freed, so let's make sure that
|
* is so by doing an extra call to the handler ....
|
*
|
* ( We do this after actually deregistering it, to make sure that a
|
* 'real' IRQ doesn't run in parallel with our fake. )
|
*/
|
if (action->flags & IRQF_SHARED) {
|
local_irq_save(flags);
|
action->handler(irq, dev_id);
|
local_irq_restore(flags);
|
}
|
#endif
|
|
/*
|
* The action has already been removed above, but the thread writes
|
* its oneshot mask bit when it completes. Though request_mutex is
|
* held across this which prevents __setup_irq() from handing out
|
* the same bit to a newly requested action.
|
*/
|
if (action->thread) {
|
kthread_stop(action->thread);
|
put_task_struct(action->thread);
|
if (action->secondary && action->secondary->thread) {
|
kthread_stop(action->secondary->thread);
|
put_task_struct(action->secondary->thread);
|
}
|
}
|
|
/* Last action releases resources */
|
if (!desc->action) {
|
/*
|
* Reaquire bus lock as irq_release_resources() might
|
* require it to deallocate resources over the slow bus.
|
*/
|
chip_bus_lock(desc);
|
/*
|
* There is no interrupt on the fly anymore. Deactivate it
|
* completely.
|
*/
|
raw_spin_lock_irqsave(&desc->lock, flags);
|
irq_domain_deactivate_irq(&desc->irq_data);
|
raw_spin_unlock_irqrestore(&desc->lock, flags);
|
|
irq_release_resources(desc);
|
chip_bus_sync_unlock(desc);
|
irq_remove_timings(desc);
|
}
|
|
mutex_unlock(&desc->request_mutex);
|
|
irq_chip_pm_put(&desc->irq_data);
|
module_put(desc->owner);
|
kfree(action->secondary);
|
return action;
|
}
|
|
/**
|
* free_irq - free an interrupt allocated with request_irq
|
* @irq: Interrupt line to free
|
* @dev_id: Device identity to free
|
*
|
* Remove an interrupt handler. The handler is removed and if the
|
* interrupt line is no longer in use by any driver it is disabled.
|
* On a shared IRQ the caller must ensure the interrupt is disabled
|
* on the card it drives before calling this function. The function
|
* does not return until any executing interrupts for this IRQ
|
* have completed.
|
*
|
* This function must not be called from interrupt context.
|
*
|
* Returns the devname argument passed to request_irq.
|
*/
|
const void *free_irq(unsigned int irq, void *dev_id)
|
{
|
struct irq_desc *desc = irq_to_desc(irq);
|
struct irqaction *action;
|
const char *devname;
|
|
if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
|
return NULL;
|
|
#ifdef CONFIG_SMP
|
if (WARN_ON(desc->affinity_notify))
|
desc->affinity_notify = NULL;
|
#endif
|
|
action = __free_irq(desc, dev_id);
|
|
if (!action)
|
return NULL;
|
|
devname = action->name;
|
kfree(action);
|
return devname;
|
}
|
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_and_deactivate(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
|
* @handler: Function to be called when the IRQ occurs.
|
* Primary handler for threaded interrupts
|
* If NULL and thread_fn != NULL the default
|
* primary handler is installed
|
* @thread_fn: Function called from the irq handler thread
|
* If NULL, no irq thread is created
|
* @irqflags: Interrupt type flags
|
* @devname: 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. From the point this
|
* call is made your handler function may be invoked. Since
|
* your handler function must clear any interrupt the board
|
* raises, you must take care both to initialise your hardware
|
* and to set up the interrupt handler in the right order.
|
*
|
* If you want to set up a threaded irq handler for your device
|
* then you need to supply @handler and @thread_fn. @handler is
|
* still called in hard interrupt context and has to check
|
* whether the interrupt originates from the device. If yes it
|
* needs to disable the interrupt on the device and return
|
* IRQ_WAKE_THREAD which will wake up the handler thread and run
|
* @thread_fn. This split handler design is necessary to support
|
* shared interrupts.
|
*
|
* 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 your interrupt is shared you must pass a non NULL dev_id
|
* as this is required when freeing the interrupt.
|
*
|
* Flags:
|
*
|
* IRQF_SHARED Interrupt is shared
|
* IRQF_TRIGGER_* Specify active edge(s) or level
|
*
|
*/
|
int request_threaded_irq(unsigned int irq, irq_handler_t handler,
|
irq_handler_t thread_fn, unsigned long irqflags,
|
const char *devname, void *dev_id)
|
{
|
struct irqaction *action;
|
struct irq_desc *desc;
|
int retval;
|
|
if (irq == IRQ_NOTCONNECTED)
|
return -ENOTCONN;
|
|
/*
|
* Sanity-check: shared interrupts must pass in a real dev-ID,
|
* otherwise we'll have trouble later trying to figure out
|
* which interrupt is which (messes up the interrupt freeing
|
* logic etc).
|
*
|
* Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
|
* it cannot be set along with IRQF_NO_SUSPEND.
|
*/
|
if (((irqflags & IRQF_SHARED) && !dev_id) ||
|
(!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
|
((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
|
return -EINVAL;
|
|
desc = irq_to_desc(irq);
|
if (!desc)
|
return -EINVAL;
|
|
if (!irq_settings_can_request(desc) ||
|
WARN_ON(irq_settings_is_per_cpu_devid(desc)))
|
return -EINVAL;
|
|
if (!handler) {
|
if (!thread_fn)
|
return -EINVAL;
|
handler = irq_default_primary_handler;
|
}
|
|
action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
|
if (!action)
|
return -ENOMEM;
|
|
action->handler = handler;
|
action->thread_fn = thread_fn;
|
action->flags = irqflags;
|
action->name = devname;
|
action->dev_id = dev_id;
|
|
retval = irq_chip_pm_get(&desc->irq_data);
|
if (retval < 0) {
|
kfree(action);
|
return retval;
|
}
|
|
retval = __setup_irq(irq, desc, action);
|
|
if (retval) {
|
irq_chip_pm_put(&desc->irq_data);
|
kfree(action->secondary);
|
kfree(action);
|
}
|
|
#ifdef CONFIG_DEBUG_SHIRQ_FIXME
|
if (!retval && (irqflags & IRQF_SHARED)) {
|
/*
|
* It's a shared IRQ -- the driver ought to be prepared for it
|
* to happen immediately, so let's make sure....
|
* We disable the irq to make sure that a 'real' IRQ doesn't
|
* run in parallel with our fake.
|
*/
|
unsigned long flags;
|
|
disable_irq(irq);
|
local_irq_save(flags);
|
|
handler(irq, dev_id);
|
|
local_irq_restore(flags);
|
enable_irq(irq);
|
}
|
#endif
|
return retval;
|
}
|
EXPORT_SYMBOL(request_threaded_irq);
|
|
/**
|
* request_any_context_irq - allocate an interrupt line
|
* @irq: Interrupt line to allocate
|
* @handler: Function to be called when the IRQ occurs.
|
* Threaded handler for threaded interrupts.
|
* @flags: 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 selects either a
|
* hardirq or threaded handling method depending on the
|
* context.
|
*
|
* On failure, it returns a negative value. On success,
|
* it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
|
*/
|
int request_any_context_irq(unsigned int irq, irq_handler_t handler,
|
unsigned long flags, const char *name, void *dev_id)
|
{
|
struct irq_desc *desc;
|
int ret;
|
|
if (irq == IRQ_NOTCONNECTED)
|
return -ENOTCONN;
|
|
desc = irq_to_desc(irq);
|
if (!desc)
|
return -EINVAL;
|
|
if (irq_settings_is_nested_thread(desc)) {
|
ret = request_threaded_irq(irq, NULL, handler,
|
flags, name, dev_id);
|
return !ret ? IRQC_IS_NESTED : ret;
|
}
|
|
ret = request_irq(irq, handler, flags, name, dev_id);
|
return !ret ? IRQC_IS_HARDIRQ : ret;
|
}
|
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();
|
unsigned long flags;
|
struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
|
|
if (!desc)
|
return;
|
|
/*
|
* If the trigger type is not specified by the caller, then
|
* use the default for this interrupt.
|
*/
|
type &= IRQ_TYPE_SENSE_MASK;
|
if (type == IRQ_TYPE_NONE)
|
type = irqd_get_trigger_type(&desc->irq_data);
|
|
if (type != IRQ_TYPE_NONE) {
|
int ret;
|
|
ret = __irq_set_trigger(desc, type);
|
|
if (ret) {
|
WARN(1, "failed to set type for IRQ%d\n", irq);
|
goto out;
|
}
|
}
|
|
irq_percpu_enable(desc, cpu);
|
out:
|
irq_put_desc_unlock(desc, flags);
|
}
|
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
|
*
|
* Must be called from a non migratable context. Returns the enable
|
* state of a per cpu interrupt on the current cpu.
|
*/
|
bool irq_percpu_is_enabled(unsigned int irq)
|
{
|
unsigned int cpu = smp_processor_id();
|
struct irq_desc *desc;
|
unsigned long flags;
|
bool is_enabled;
|
|
desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
|
if (!desc)
|
return false;
|
|
is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
|
irq_put_desc_unlock(desc, flags);
|
|
return is_enabled;
|
}
|
EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
|
|
void disable_percpu_irq(unsigned int irq)
|
{
|
unsigned int cpu = smp_processor_id();
|
unsigned long flags;
|
struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
|
|
if (!desc)
|
return;
|
|
irq_percpu_disable(desc, cpu);
|
irq_put_desc_unlock(desc, flags);
|
}
|
EXPORT_SYMBOL_GPL(disable_percpu_irq);
|
|
void disable_percpu_nmi(unsigned int irq)
|
{
|
disable_percpu_irq(irq);
|
}
|
|
/*
|
* Internal function to unregister a percpu irqaction.
|
*/
|
static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
|
{
|
struct irq_desc *desc = irq_to_desc(irq);
|
struct irqaction *action;
|
unsigned long flags;
|
|
WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
|
|
if (!desc)
|
return NULL;
|
|
raw_spin_lock_irqsave(&desc->lock, flags);
|
|
action = desc->action;
|
if (!action || action->percpu_dev_id != dev_id) {
|
WARN(1, "Trying to free already-free IRQ %d\n", irq);
|
goto bad;
|
}
|
|
if (!cpumask_empty(desc->percpu_enabled)) {
|
WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
|
irq, cpumask_first(desc->percpu_enabled));
|
goto bad;
|
}
|
|
/* 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);
|
|
irq_chip_pm_put(&desc->irq_data);
|
module_put(desc->owner);
|
return action;
|
|
bad:
|
raw_spin_unlock_irqrestore(&desc->lock, flags);
|
return NULL;
|
}
|
|
/**
|
* remove_percpu_irq - free a per-cpu interrupt
|
* @irq: Interrupt line to free
|
* @act: irqaction for the interrupt
|
*
|
* Used to remove interrupts statically setup by the early boot process.
|
*/
|
void remove_percpu_irq(unsigned int irq, struct irqaction *act)
|
{
|
struct irq_desc *desc = irq_to_desc(irq);
|
|
if (desc && irq_settings_is_per_cpu_devid(desc))
|
__free_percpu_irq(irq, act->percpu_dev_id);
|
}
|
|
/**
|
* free_percpu_irq - free an interrupt allocated with request_percpu_irq
|
* @irq: Interrupt line to free
|
* @dev_id: Device identity to free
|
*
|
* Remove a percpu interrupt handler. The handler is removed, but
|
* the interrupt line is not disabled. This must be done on each
|
* CPU before calling this function. The function does not return
|
* until any executing interrupts for this IRQ have completed.
|
*
|
* This function must not be called from interrupt context.
|
*/
|
void free_percpu_irq(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;
|
|
chip_bus_lock(desc);
|
kfree(__free_percpu_irq(irq, dev_id));
|
chip_bus_sync_unlock(desc);
|
}
|
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
|
* @act: irqaction for the interrupt
|
*
|
* Used to statically setup per-cpu interrupts in the early boot process.
|
*/
|
int setup_percpu_irq(unsigned int irq, struct irqaction *act)
|
{
|
struct irq_desc *desc = irq_to_desc(irq);
|
int retval;
|
|
if (!desc || !irq_settings_is_per_cpu_devid(desc))
|
return -EINVAL;
|
|
retval = irq_chip_pm_get(&desc->irq_data);
|
if (retval < 0)
|
return retval;
|
|
retval = __setup_irq(irq, desc, act);
|
|
if (retval)
|
irq_chip_pm_put(&desc->irq_data);
|
|
return retval;
|
}
|
|
/**
|
* __request_percpu_irq - allocate a percpu interrupt line
|
* @irq: Interrupt line to allocate
|
* @handler: Function to be called when the IRQ occurs.
|
* @flags: Interrupt type flags (IRQF_TIMER only)
|
* @devname: An ascii name for the claiming device
|
* @dev_id: A percpu cookie passed back to the handler function
|
*
|
* This call allocates interrupt resources and enables the
|
* interrupt on the local CPU. If the interrupt is supposed to be
|
* enabled on other CPUs, it has to be done on each CPU using
|
* enable_percpu_irq().
|
*
|
* 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.
|
*/
|
int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
|
unsigned long flags, const char *devname,
|
void __percpu *dev_id)
|
{
|
struct irqaction *action;
|
struct irq_desc *desc;
|
int retval;
|
|
if (!dev_id)
|
return -EINVAL;
|
|
desc = irq_to_desc(irq);
|
if (!desc || !irq_settings_can_request(desc) ||
|
!irq_settings_is_per_cpu_devid(desc))
|
return -EINVAL;
|
|
if (flags && flags != IRQF_TIMER)
|
return -EINVAL;
|
|
action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
|
if (!action)
|
return -ENOMEM;
|
|
action->handler = handler;
|
action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
|
action->name = devname;
|
action->percpu_dev_id = dev_id;
|
|
retval = irq_chip_pm_get(&desc->irq_data);
|
if (retval < 0) {
|
kfree(action);
|
return retval;
|
}
|
|
retval = __setup_irq(irq, desc, action);
|
|
if (retval) {
|
irq_chip_pm_put(&desc->irq_data);
|
kfree(action);
|
}
|
|
return retval;
|
}
|
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);
|
}
|
|
int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
|
bool *state)
|
{
|
struct irq_chip *chip;
|
int err = -EINVAL;
|
|
do {
|
chip = irq_data_get_irq_chip(data);
|
if (WARN_ON_ONCE(!chip))
|
return -ENODEV;
|
if (chip->irq_get_irqchip_state)
|
break;
|
#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
|
data = data->parent_data;
|
#else
|
data = NULL;
|
#endif
|
} while (data);
|
|
if (data)
|
err = chip->irq_get_irqchip_state(data, which, state);
|
return err;
|
}
|
|
/**
|
* 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
|
* @state: a pointer to a boolean where the state is to be storeed
|
*
|
* This call snapshots the internal irqchip state of an
|
* interrupt, returning into @state the bit corresponding to
|
* stage @which
|
*
|
* This function should be called with preemption disabled if the
|
* interrupt controller has per-cpu registers.
|
*/
|
int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
|
bool *state)
|
{
|
struct irq_desc *desc;
|
struct irq_data *data;
|
unsigned long flags;
|
int err = -EINVAL;
|
|
desc = irq_get_desc_buslock(irq, &flags, 0);
|
if (!desc)
|
return err;
|
|
data = irq_desc_get_irq_data(desc);
|
|
err = __irq_get_irqchip_state(data, which, state);
|
|
irq_put_desc_busunlock(desc, flags);
|
return err;
|
}
|
EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
|
|
/**
|
* irq_set_irqchip_state - set the state of a forwarded interrupt.
|
* @irq: Interrupt line that is forwarded to a VM
|
* @which: State to be restored (one of IRQCHIP_STATE_*)
|
* @val: Value corresponding to @which
|
*
|
* This call sets the internal irqchip state of an interrupt,
|
* depending on the value of @which.
|
*
|
* This function should be called with migration disabled if the
|
* interrupt controller has per-cpu registers.
|
*/
|
int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
|
bool val)
|
{
|
struct irq_desc *desc;
|
struct irq_data *data;
|
struct irq_chip *chip;
|
unsigned long flags;
|
int err = -EINVAL;
|
|
desc = irq_get_desc_buslock(irq, &flags, 0);
|
if (!desc)
|
return err;
|
|
data = irq_desc_get_irq_data(desc);
|
|
do {
|
chip = irq_data_get_irq_chip(data);
|
if (WARN_ON_ONCE(!chip)) {
|
err = -ENODEV;
|
goto out_unlock;
|
}
|
if (chip->irq_set_irqchip_state)
|
break;
|
#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
|
data = data->parent_data;
|
#else
|
data = NULL;
|
#endif
|
} while (data);
|
|
if (data)
|
err = chip->irq_set_irqchip_state(data, which, val);
|
|
out_unlock:
|
irq_put_desc_busunlock(desc, flags);
|
return err;
|
}
|
EXPORT_SYMBOL_GPL(irq_set_irqchip_state);
|
