1 // SPDX-License-Identifier: GPL-2.0-only
3  * IRQ offload/bypass manager
10  * Interrupts on Intel VT-d systems can allow interrupts to be received
11  * directly by a virtual machine.  ARM IRQ Forwarding allows forwarded physical
23 MODULE_DESCRIPTION("IRQ bypass manager utility module");
35 	if (prod->stop)  in __connect()
36 		prod->stop(prod);  in __connect()
37 	if (cons->stop)  in __connect()
38 		cons->stop(cons);  in __connect()
40 	if (prod->add_consumer)  in __connect()
41 		ret = prod->add_consumer(prod, cons);  in __connect()
44 		ret = cons->add_producer(cons, prod);  in __connect()
45 		if (ret && prod->del_consumer)  in __connect()
46 			prod->del_consumer(prod, cons);  in __connect()
49 	if (cons->start)  in __connect()
50 		cons->start(cons);  in __connect()
51 	if (prod->start)  in __connect()
52 		prod->start(prod);  in __connect()
55 		prod->consumer = cons;  in __connect()
56 		cons->producer = prod;  in __connect()
65 	if (prod->stop)  in __disconnect()
66 		prod->stop(prod);  in __disconnect()
67 	if (cons->stop)  in __disconnect()
68 		cons->stop(cons);  in __disconnect()
70 	cons->del_producer(cons, prod);  in __disconnect()
72 	if (prod->del_consumer)  in __disconnect()
73 		prod->del_consumer(prod, cons);  in __disconnect()
75 	if (cons->start)  in __disconnect()
76 		cons->start(cons);  in __disconnect()
77 	if (prod->start)  in __disconnect()
78 		prod->start(prod);  in __disconnect()
80 	prod->consumer = NULL;  in __disconnect()
81 	cons->producer = NULL;  in __disconnect()
85  * irq_bypass_register_producer - register IRQ bypass producer
88  * @irq: Linux IRQ number of the underlying producer device
90  * Add the provided IRQ producer to the set of producers and connect with the
94 				 struct eventfd_ctx *eventfd, int irq)  in irq_bypass_register_producer()
100 	if (WARN_ON_ONCE(producer->eventfd))  in irq_bypass_register_producer()
101 		return -EINVAL;  in irq_bypass_register_producer()
103 	producer->irq = irq;  in irq_bypass_register_producer()
120 	producer->eventfd = eventfd;  in irq_bypass_register_producer()
126  * irq_bypass_unregister_producer - unregister IRQ bypass producer
129  * Remove a previously registered IRQ producer (note, it's safe to call this
135 	unsigned long index = (unsigned long)producer->eventfd;  in irq_bypass_unregister_producer()
137 	if (!producer->eventfd)  in irq_bypass_unregister_producer()
142 	if (producer->consumer)  in irq_bypass_unregister_producer()
143 		__disconnect(producer, producer->consumer);  in irq_bypass_unregister_producer()
146 	producer->eventfd = NULL;  in irq_bypass_unregister_producer()
151  * irq_bypass_register_consumer - register IRQ bypass consumer
155  * Add the provided IRQ consumer to the set of consumers and connect with the
165 	if (WARN_ON_ONCE(consumer->eventfd))  in irq_bypass_register_consumer()
166 		return -EINVAL;  in irq_bypass_register_consumer()
168 	if (!consumer->add_producer || !consumer->del_producer)  in irq_bypass_register_consumer()
169 		return -EINVAL;  in irq_bypass_register_consumer()
186 	consumer->eventfd = eventfd;  in irq_bypass_register_consumer()
192  * irq_bypass_unregister_consumer - unregister IRQ bypass consumer
195  * Remove a previously registered IRQ consumer (note, it's safe to call this
201 	unsigned long index = (unsigned long)consumer->eventfd;  in irq_bypass_unregister_consumer()
203 	if (!consumer->eventfd)  in irq_bypass_unregister_consumer()
208 	if (consumer->producer)  in irq_bypass_unregister_consumer()
209 		__disconnect(consumer->producer, consumer);  in irq_bypass_unregister_consumer()
212 	consumer->eventfd = NULL;  in irq_bypass_unregister_consumer()