Allocate, bind, and service Xen event channels from Zephyr. More...

Files
file	events.h
	Xen event channel services.

Typedefs
typedef void(*	evtchn_cb_t) (void *priv)
	Event-channel callback signature.

Functions
int	evtchn_status (evtchn_status_t *status)
	Query the status of an event channel.
int	evtchn_close (evtchn_port_t port)
	Close a local event channel.
int	evtchn_set_priority (evtchn_port_t port, uint32_t priority)
	Set the Xen priority assigned to an event channel.
int	notify_evtchn (evtchn_port_t port)
	Send a notification over an event channel.
int	alloc_unbound_event_channel (domid_t remote_dom)
	Allocate an unbound event channel for the calling domain.
int	alloc_unbound_event_channel_dom0 (domid_t dom, domid_t remote_dom)
	Allocate an unbound event channel between two domains.
int	bind_interdomain_event_channel (domid_t remote_dom, evtchn_port_t remote_port, evtchn_cb_t cb, void *data)
	Bind to a remote event channel and register a callback.
int	bind_event_channel (evtchn_port_t port, evtchn_cb_t cb, void *data)
	Attach a callback to an already allocated local event channel.
int	unbind_event_channel (evtchn_port_t port)
	Remove the callback bound to an event channel.
int	get_missed_events (evtchn_port_t port)
	Get and clear the missed-event state for an unbound channel.
int	mask_event_channel (evtchn_port_t port)
	Mask local delivery for an event channel.
int	unmask_event_channel (evtchn_port_t port)
	Unmask local delivery for an event channel.
void	clear_event_channel (evtchn_port_t port)
	Clear the pending bit for an event channel.
int	xen_events_init (void)
	Initialize Xen event handling for the current guest.

Detailed Description

Allocate, bind, and service Xen event channels from Zephyr.

Typedef Documentation

◆ evtchn_cb_t

typedef void(* evtchn_cb_t) (void *priv)

#include <zephyr/xen/events.h>

Event-channel callback signature.

The callback runs from the Xen event interrupt handler.

Parameters

priv	User data pointer that was registered with the event channel.

Function Documentation

◆ alloc_unbound_event_channel()

int alloc_unbound_event_channel ( domid_t remote_dom )

#include <zephyr/xen/events.h>

Allocate an unbound event channel for the calling domain.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

remote_dom Domain that may bind to the allocated channel.

Returns: Local event-channel port on success, negative errno value on failure.

◆ alloc_unbound_event_channel_dom0()

int alloc_unbound_event_channel_dom0	(	domid_t	dom,
		domid_t	remote_dom )

#include <zephyr/xen/events.h>

Allocate an unbound event channel between two domains.

Attention: Available only when the following Kconfig options are enabled: CONFIG_XEN_EVENTS, CONFIG_XEN_DOM0.

Parameters

dom	Domain that receives the new local port. May be DOMID_SELF.
remote_dom	Peer domain that may bind to the port.

Returns: Local event-channel port on success, negative errno value on failure.

◆ bind_event_channel()

int bind_event_channel	(	evtchn_port_t	port,
		evtchn_cb_t	cb,
		void *	data )

#include <zephyr/xen/events.h>

Attach a callback to an already allocated local event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

port	Local event-channel port number.
cb	Callback to invoke when the port is signaled.
data	User data pointer passed to `cb`.

Return values

0	on success.

◆ bind_interdomain_event_channel()

int bind_interdomain_event_channel	(	domid_t	remote_dom,
		evtchn_port_t	remote_port,
		evtchn_cb_t	cb,
		void *	data )

#include <zephyr/xen/events.h>

Bind to a remote event channel and register a callback.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

remote_dom	Peer domain that already owns `remote_port`.
remote_port	Event-channel port in `remote_dom`.
cb	Callback invoked when the local channel fires.
data	User data pointer passed to `cb`.

Returns: Local event-channel port on success, negative errno value on failure.

◆ clear_event_channel()

void clear_event_channel ( evtchn_port_t port )

#include <zephyr/xen/events.h>

Clear the pending bit for an event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

port	Local event-channel port number.

◆ evtchn_close()

int evtchn_close ( evtchn_port_t port )

#include <zephyr/xen/events.h>

Close a local event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

port	Local event-channel port to close.

Returns: 0 on success, negative errno value on failure.

◆ evtchn_set_priority()

int evtchn_set_priority	(	evtchn_port_t	port,
		uint32_t	priority )

#include <zephyr/xen/events.h>

Set the Xen priority assigned to an event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

port	Local event-channel port to update.
priority	Xen event priority value.

Returns: 0 on success, negative errno value on failure.

◆ evtchn_status()

int evtchn_status ( evtchn_status_t * status )

#include <zephyr/xen/events.h>

Query the status of an event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

The caller provides the input domain and port in status, and Xen fills the remaining fields with the current channel state.

Parameters

[in,out] status Event-channel status request and response buffer.

Returns: 0 on success, negative errno value on failure.

◆ get_missed_events()

int get_missed_events ( evtchn_port_t port )

#include <zephyr/xen/events.h>

Get and clear the missed-event state for an unbound channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

port	Local event-channel port number.

Return values

1	At least one event was recorded while no callback was bound.
0	Otherwise.

◆ mask_event_channel()

int mask_event_channel ( evtchn_port_t port )

#include <zephyr/xen/events.h>

Mask local delivery for an event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

port	Local event-channel port number.

Return values

0	Always returned after updating the shared-info mask bit.

◆ notify_evtchn()

int notify_evtchn ( evtchn_port_t port )

#include <zephyr/xen/events.h>

Send a notification over an event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

port	Local event-channel port to notify.

Returns: 0 on success, negative errno value on failure.

◆ unbind_event_channel()

int unbind_event_channel ( evtchn_port_t port )

#include <zephyr/xen/events.h>

Remove the callback bound to an event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

The channel remains allocated, but subsequent notifications are recorded as missed events until another callback is registered.

Parameters

port	Local event-channel port number.

Return values

0	on success.

◆ unmask_event_channel()

int unmask_event_channel ( evtchn_port_t port )

#include <zephyr/xen/events.h>

Unmask local delivery for an event channel.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

Parameters

port	Local event-channel port number.

Return values

0	Always returned after updating the shared-info mask bit.

◆ xen_events_init()

int xen_events_init ( void )

#include <zephyr/xen/events.h>

Initialize Xen event handling for the current guest.

Attention: Available only when the following Kconfig option is enabled: CONFIG_XEN_EVENTS.

This function prepares the per-port callback table and connects the Zephyr ISR to the Xen event interrupt described by devicetree.

Returns: 0 on success, negative errno value on failure.

Return values

-EINVAL Xen shared-info page is not mapped.

Files

Typedefs

Functions

Detailed Description

Typedef Documentation

◆ evtchn_cb_t

Function Documentation

◆ alloc_unbound_event_channel()

◆ alloc_unbound_event_channel_dom0()

◆ bind_event_channel()

◆ bind_interdomain_event_channel()

◆ clear_event_channel()

◆ evtchn_close()

◆ evtchn_set_priority()

◆ evtchn_status()

◆ get_missed_events()

◆ mask_event_channel()

◆ notify_evtchn()

◆ unbind_event_channel()

◆ unmask_event_channel()

◆ xen_events_init()