Release 4.15 virt/lib/irqbypass.c
/*
* IRQ offload/bypass manager
*
* Copyright (C) 2015 Red Hat, Inc.
* Copyright (c) 2015 Linaro Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Various virtualization hardware acceleration techniques allow bypassing or
* offloading interrupts received from devices around the host kernel. Posted
* Interrupts on Intel VT-d systems can allow interrupts to be received
* directly by a virtual machine. ARM IRQ Forwarding allows forwarded physical
* interrupts to be directly deactivated by the guest. This manager allows
* interrupt producers and consumers to find each other to enable this sort of
* bypass.
*/
#include <linux/irqbypass.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("IRQ bypass manager utility module");
static LIST_HEAD(producers);
static LIST_HEAD(consumers);
static DEFINE_MUTEX(lock);
/* @lock must be held when calling connect */
static int __connect(struct irq_bypass_producer *prod,
struct irq_bypass_consumer *cons)
{
int ret = 0;
if (prod->stop)
prod->stop(prod);
if (cons->stop)
cons->stop(cons);
if (prod->add_consumer)
ret = prod->add_consumer(prod, cons);
if (!ret) {
ret = cons->add_producer(cons, prod);
if (ret && prod->del_consumer)
prod->del_consumer(prod, cons);
}
if (cons->start)
cons->start(cons);
if (prod->start)
prod->start(prod);
return ret;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Alex Williamson | 128 | 100.00% | 1 | 100.00% |
| Total | 128 | 100.00% | 1 | 100.00% |
/* @lock must be held when calling disconnect */
static void __disconnect(struct irq_bypass_producer *prod,
struct irq_bypass_consumer *cons)
{
if (prod->stop)
prod->stop(prod);
if (cons->stop)
cons->stop(cons);
cons->del_producer(cons, prod);
if (prod->del_consumer)
prod->del_consumer(prod, cons);
if (cons->start)
cons->start(cons);
if (prod->start)
prod->start(prod);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Alex Williamson | 92 | 100.00% | 1 | 100.00% |
| Total | 92 | 100.00% | 1 | 100.00% |
/**
* irq_bypass_register_producer - register IRQ bypass producer
* @producer: pointer to producer structure
*
* Add the provided IRQ producer to the list of producers and connect
* with any matching token found on the IRQ consumers list.
*/
int irq_bypass_register_producer(struct irq_bypass_producer *producer)
{
struct irq_bypass_producer *tmp;
struct irq_bypass_consumer *consumer;
if (!producer->token)
return -EINVAL;
might_sleep();
if (!try_module_get(THIS_MODULE))
return -ENODEV;
mutex_lock(&lock);
list_for_each_entry(tmp, &producers, node) {
if (tmp->token == producer->token) {
mutex_unlock(&lock);
module_put(THIS_MODULE);
return -EBUSY;
}
}
list_for_each_entry(consumer, &consumers, node) {
if (consumer->token == producer->token) {
int ret = __connect(producer, consumer);
if (ret) {
mutex_unlock(&lock);
module_put(THIS_MODULE);
return ret;
}
break;
}
}
list_add(&producer->node, &producers);
mutex_unlock(&lock);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Alex Williamson | 162 | 100.00% | 2 | 100.00% |
| Total | 162 | 100.00% | 2 | 100.00% |
EXPORT_SYMBOL_GPL(irq_bypass_register_producer);
/**
* irq_bypass_unregister_producer - unregister IRQ bypass producer
* @producer: pointer to producer structure
*
* Remove a previously registered IRQ producer from the list of producers
* and disconnect it from any connected IRQ consumer.
*/
void irq_bypass_unregister_producer(struct irq_bypass_producer *producer)
{
struct irq_bypass_producer *tmp;
struct irq_bypass_consumer *consumer;
if (!producer->token)
return;
might_sleep();
if (!try_module_get(THIS_MODULE))
return; /* nothing in the list anyway */
mutex_lock(&lock);
list_for_each_entry(tmp, &producers, node) {
if (tmp->token != producer->token)
continue;
list_for_each_entry(consumer, &consumers, node) {
if (consumer->token == producer->token) {
__disconnect(producer, consumer);
break;
}
}
list_del(&producer->node);
module_put(THIS_MODULE);
break;
}
mutex_unlock(&lock);
module_put(THIS_MODULE);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Alex Williamson | 123 | 100.00% | 2 | 100.00% |
| Total | 123 | 100.00% | 2 | 100.00% |
EXPORT_SYMBOL_GPL(irq_bypass_unregister_producer);
/**
* irq_bypass_register_consumer - register IRQ bypass consumer
* @consumer: pointer to consumer structure
*
* Add the provided IRQ consumer to the list of consumers and connect
* with any matching token found on the IRQ producer list.
*/
int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer)
{
struct irq_bypass_consumer *tmp;
struct irq_bypass_producer *producer;
if (!consumer->token ||
!consumer->add_producer || !consumer->del_producer)
return -EINVAL;
might_sleep();
if (!try_module_get(THIS_MODULE))
return -ENODEV;
mutex_lock(&lock);
list_for_each_entry(tmp, &consumers, node) {
if (tmp->token == consumer->token || tmp == consumer) {
mutex_unlock(&lock);
module_put(THIS_MODULE);
return -EBUSY;
}
}
list_for_each_entry(producer, &producers, node) {
if (producer->token == consumer->token) {
int ret = __connect(producer, consumer);
if (ret) {
mutex_unlock(&lock);
module_put(THIS_MODULE);
return ret;
}
break;
}
}
list_add(&consumer->node, &consumers);
mutex_unlock(&lock);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Alex Williamson | 172 | 97.73% | 2 | 66.67% |
| Wanpeng Li | 4 | 2.27% | 1 | 33.33% |
| Total | 176 | 100.00% | 3 | 100.00% |
EXPORT_SYMBOL_GPL(irq_bypass_register_consumer);
/**
* irq_bypass_unregister_consumer - unregister IRQ bypass consumer
* @consumer: pointer to consumer structure
*
* Remove a previously registered IRQ consumer from the list of consumers
* and disconnect it from any connected IRQ producer.
*/
void irq_bypass_unregister_consumer(struct irq_bypass_consumer *consumer)
{
struct irq_bypass_consumer *tmp;
struct irq_bypass_producer *producer;
if (!consumer->token)
return;
might_sleep();
if (!try_module_get(THIS_MODULE))
return; /* nothing in the list anyway */
mutex_lock(&lock);
list_for_each_entry(tmp, &consumers, node) {
if (tmp != consumer)
continue;
list_for_each_entry(producer, &producers, node) {
if (producer->token == consumer->token) {
__disconnect(producer, consumer);
break;
}
}
list_del(&consumer->node);
module_put(THIS_MODULE);
break;
}
mutex_unlock(&lock);
module_put(THIS_MODULE);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Alex Williamson | 119 | 100.00% | 2 | 100.00% |
| Total | 119 | 100.00% | 2 | 100.00% |
EXPORT_SYMBOL_GPL(irq_bypass_unregister_consumer);
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Alex Williamson | 863 | 99.54% | 2 | 66.67% |
| Wanpeng Li | 4 | 0.46% | 1 | 33.33% |
| Total | 867 | 100.00% | 3 | 100.00% |
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.