91 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			91 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * IRQ offload/bypass manager
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|  *
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|  * Copyright (C) 2015 Red Hat, Inc.
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|  * Copyright (c) 2015 Linaro Ltd.
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  */
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| #ifndef IRQBYPASS_H
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| #define IRQBYPASS_H
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| 
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| #include <linux/list.h>
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| 
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| struct irq_bypass_consumer;
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| 
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| /*
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|  * Theory of operation
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|  *
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|  * The IRQ bypass manager is a simple set of lists and callbacks that allows
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|  * IRQ producers (ex. physical interrupt sources) to be matched to IRQ
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|  * consumers (ex. virtualization hardware that allows IRQ bypass or offload)
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|  * via a shared token (ex. eventfd_ctx).  Producers and consumers register
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|  * independently.  When a token match is found, the optional @stop callback
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|  * will be called for each participant.  The pair will then be connected via
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|  * the @add_* callbacks, and finally the optional @start callback will allow
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|  * any final coordination.  When either participant is unregistered, the
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|  * process is repeated using the @del_* callbacks in place of the @add_*
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|  * callbacks.  Match tokens must be unique per producer/consumer, 1:N pairings
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|  * are not supported.
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|  */
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| 
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| /**
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|  * struct irq_bypass_producer - IRQ bypass producer definition
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|  * @node: IRQ bypass manager private list management
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|  * @token: opaque token to match between producer and consumer (non-NULL)
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|  * @irq: Linux IRQ number for the producer device
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|  * @add_consumer: Connect the IRQ producer to an IRQ consumer (optional)
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|  * @del_consumer: Disconnect the IRQ producer from an IRQ consumer (optional)
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|  * @stop: Perform any quiesce operations necessary prior to add/del (optional)
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|  * @start: Perform any startup operations necessary after add/del (optional)
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|  *
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|  * The IRQ bypass producer structure represents an interrupt source for
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|  * participation in possible host bypass, for instance an interrupt vector
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|  * for a physical device assigned to a VM.
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|  */
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| struct irq_bypass_producer {
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| 	struct list_head node;
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| 	void *token;
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| 	int irq;
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| 	int (*add_consumer)(struct irq_bypass_producer *,
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| 			    struct irq_bypass_consumer *);
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| 	void (*del_consumer)(struct irq_bypass_producer *,
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| 			     struct irq_bypass_consumer *);
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| 	void (*stop)(struct irq_bypass_producer *);
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| 	void (*start)(struct irq_bypass_producer *);
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| };
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| 
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| /**
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|  * struct irq_bypass_consumer - IRQ bypass consumer definition
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|  * @node: IRQ bypass manager private list management
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|  * @token: opaque token to match between producer and consumer (non-NULL)
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|  * @add_producer: Connect the IRQ consumer to an IRQ producer
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|  * @del_producer: Disconnect the IRQ consumer from an IRQ producer
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|  * @stop: Perform any quiesce operations necessary prior to add/del (optional)
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|  * @start: Perform any startup operations necessary after add/del (optional)
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|  *
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|  * The IRQ bypass consumer structure represents an interrupt sink for
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|  * participation in possible host bypass, for instance a hypervisor may
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|  * support offloads to allow bypassing the host entirely or offload
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|  * portions of the interrupt handling to the VM.
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|  */
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| struct irq_bypass_consumer {
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| 	struct list_head node;
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| 	void *token;
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| 	int (*add_producer)(struct irq_bypass_consumer *,
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| 			    struct irq_bypass_producer *);
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| 	void (*del_producer)(struct irq_bypass_consumer *,
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| 			     struct irq_bypass_producer *);
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| 	void (*stop)(struct irq_bypass_consumer *);
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| 	void (*start)(struct irq_bypass_consumer *);
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| };
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| 
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| int irq_bypass_register_producer(struct irq_bypass_producer *);
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| void irq_bypass_unregister_producer(struct irq_bypass_producer *);
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| int irq_bypass_register_consumer(struct irq_bypass_consumer *);
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| void irq_bypass_unregister_consumer(struct irq_bypass_consumer *);
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| 
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| #endif /* IRQBYPASS_H */
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