freebsd-dev/sys/xen/xen_intr.h
Roger Pau Monné 0f4d7d9fd7 xen/intr: add reference counts to event channels
Add a reference count to xenisrc. This is required for implementation of
unmap-notifications in the grant table userspace device (gntdev). We need to
hold a reference to the event channel port, in case the user deallocates the
port before we send the notification.

Submitted by:		jaggi
Reviewed by:		royger
Differential review:	https://reviews.freebsd.org/D7429
2016-10-31 13:00:53 +00:00

279 lines
11 KiB
C

/******************************************************************************
* xen_intr.h
*
* APIs for managing Xen event channel, virtual IRQ, and physical IRQ
* notifications.
*
* Copyright (c) 2004, K A Fraser
* Copyright (c) 2012, Spectra Logic Corporation
*
* This file may be distributed separately from the Linux kernel, or
* incorporated into other software packages, subject to the following license:
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this source file (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* $FreeBSD$
*/
#ifndef _XEN_INTR_H_
#define _XEN_INTR_H_
#include <xen/interface/event_channel.h>
/** Registered Xen interrupt callback handle. */
typedef void * xen_intr_handle_t;
/** If non-zero, the hypervisor has been configured to use a direct vector */
extern int xen_vector_callback_enabled;
void xen_intr_handle_upcall(struct trapframe *trap_frame);
/**
* Associate an already allocated local event channel port an interrupt
* handler.
*
* \param dev The device making this bind request.
* \param local_port The event channel to bind.
* \param filter An interrupt filter handler. Specify NULL
* to always dispatch to the ithread handler.
* \param handler An interrupt ithread handler. Optional (can
* specify NULL) if all necessary event actions
* are performed by filter.
* \param arg Argument to present to both filter and handler.
* \param irqflags Interrupt handler flags. See sys/bus.h.
* \param handlep Pointer to an opaque handle used to manage this
* registration.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_intr_bind_local_port(device_t dev, evtchn_port_t local_port,
driver_filter_t filter, driver_intr_t handler, void *arg,
enum intr_type irqflags, xen_intr_handle_t *handlep);
/**
* Allocate a local event channel port, accessible by the specified
* remote/foreign domain and, if successful, associate the port with
* the specified interrupt handler.
*
* \param dev The device making this bind request.
* \param remote_domain Remote domain grant permission to signal the
* newly allocated local port.
* \param filter An interrupt filter handler. Specify NULL
* to always dispatch to the ithread handler.
* \param handler An interrupt ithread handler. Optional (can
* specify NULL) if all necessary event actions
* are performed by filter.
* \param arg Argument to present to both filter and handler.
* \param irqflags Interrupt handler flags. See sys/bus.h.
* \param handlep Pointer to an opaque handle used to manage this
* registration.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_intr_alloc_and_bind_local_port(device_t dev,
u_int remote_domain, driver_filter_t filter, driver_intr_t handler,
void *arg, enum intr_type irqflags, xen_intr_handle_t *handlep);
/**
* Associate the specified interrupt handler with the remote event
* channel port specified by remote_domain and remote_port.
*
* \param dev The device making this bind request.
* \param remote_domain The domain peer for this event channel connection.
* \param remote_port Remote domain's local port number for this event
* channel port.
* \param filter An interrupt filter handler. Specify NULL
* to always dispatch to the ithread handler.
* \param handler An interrupt ithread handler. Optional (can
* specify NULL) if all necessary event actions
* are performed by filter.
* \param arg Argument to present to both filter and handler.
* \param irqflags Interrupt handler flags. See sys/bus.h.
* \param handlep Pointer to an opaque handle used to manage this
* registration.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_intr_bind_remote_port(device_t dev, u_int remote_domain,
evtchn_port_t remote_port, driver_filter_t filter,
driver_intr_t handler, void *arg, enum intr_type irqflags,
xen_intr_handle_t *handlep);
/**
* Associate the specified interrupt handler with the specified Xen
* virtual interrupt source.
*
* \param dev The device making this bind request.
* \param virq The Xen virtual IRQ number for the Xen interrupt
* source being hooked.
* \param cpu The cpu on which interrupt events should be delivered.
* \param filter An interrupt filter handler. Specify NULL
* to always dispatch to the ithread handler.
* \param handler An interrupt ithread handler. Optional (can
* specify NULL) if all necessary event actions
* are performed by filter.
* \param arg Argument to present to both filter and handler.
* \param irqflags Interrupt handler flags. See sys/bus.h.
* \param handlep Pointer to an opaque handle used to manage this
* registration.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_intr_bind_virq(device_t dev, u_int virq, u_int cpu,
driver_filter_t filter, driver_intr_t handler,
void *arg, enum intr_type irqflags, xen_intr_handle_t *handlep);
/**
* Allocate a local event channel port for servicing interprocessor
* interupts and, if successful, associate the port with the specified
* interrupt handler.
*
* \param dev The device making this bind request.
* \param cpu The cpu receiving the IPI.
* \param filter The interrupt filter servicing this IPI.
* \param irqflags Interrupt handler flags. See sys/bus.h.
* \param handlep Pointer to an opaque handle used to manage this
* registration.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_intr_alloc_and_bind_ipi(device_t dev, u_int cpu,
driver_filter_t filter, enum intr_type irqflags,
xen_intr_handle_t *handlep);
/**
* Register a physical interrupt vector and setup the interrupt source.
*
* \param vector The global vector to use.
* \param trig Default trigger method.
* \param pol Default polarity of the interrupt.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_register_pirq(int vector, enum intr_trigger trig,
enum intr_polarity pol);
/**
* Unbind an interrupt handler from its interrupt source.
*
* \param handlep A pointer to the opaque handle that was initialized
* at the time the interrupt source was bound.
*
* \returns 0 on success, otherwise an errno.
*
* \note The event channel, if any, that was allocated at bind time is
* closed upon successful return of this method.
*
* \note It is always safe to call xen_intr_unbind() on a handle that
* has been initilized to NULL.
*/
void xen_intr_unbind(xen_intr_handle_t *handle);
/**
* Add a description to an interrupt handler.
*
* \param handle The opaque handle that was initialized at the time
* the interrupt source was bound.
*
* \param fmt The sprintf compatible format string for the description,
* followed by optional sprintf arguments.
*
* \returns 0 on success, otherwise an errno.
*/
int
xen_intr_describe(xen_intr_handle_t port_handle, const char *fmt, ...)
__attribute__((format(printf, 2, 3)));
/**
* Signal the remote peer of an interrupt source associated with an
* event channel port.
*
* \param handle The opaque handle that was initialized at the time
* the interrupt source was bound.
*
* \note For xen interrupt sources other than event channel ports,
* this method takes no action.
*/
void xen_intr_signal(xen_intr_handle_t handle);
/**
* Get the local event channel port number associated with this interrupt
* source.
*
* \param handle The opaque handle that was initialized at the time
* the interrupt source was bound.
*
* \returns 0 if the handle is invalid, otherwise positive port number.
*/
evtchn_port_t xen_intr_port(xen_intr_handle_t handle);
/**
* Setup MSI vector interrupt(s).
*
* \param dev The device that requests the binding.
*
* \param vector Requested initial vector to bind the MSI interrupt(s) to.
*
* \param count Number of vectors to allocate.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_register_msi(device_t dev, int vector, int count);
/**
* Teardown a MSI vector interrupt.
*
* \param vector Requested vector to release.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_release_msi(int vector);
/**
* Bind an event channel port with a handler
*
* \param dev The device making this bind request.
* \param filter An interrupt filter handler. Specify NULL
* to always dispatch to the ithread handler.
* \param handler An interrupt ithread handler. Optional (can
* specify NULL) if all necessary event actions
* are performed by filter.
* \param arg Argument to present to both filter and handler.
* \param irqflags Interrupt handler flags. See sys/bus.h.
* \param handle Opaque handle used to manage this registration.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_intr_add_handler(device_t dev, driver_filter_t filter,
driver_intr_t handler, void *arg, enum intr_type flags,
xen_intr_handle_t handle);
/**
* Get a reference to an event channel port
*
* \param port Event channel port to which we get a reference.
* \param handlep Pointer to an opaque handle used to manage this
* registration.
*
* \returns 0 on success, otherwise an errno.
*/
int xen_intr_get_evtchn_from_port(evtchn_port_t port,
xen_intr_handle_t *handlep);
#endif /* _XEN_INTR_H_ */