linux-stable/drivers/xen/events/events_internal.h
Juergen Gross 25da4618af xen/events: don't unmask an event channel when an eoi is pending
An event channel should be kept masked when an eoi is pending for it.
When being migrated to another cpu it might be unmasked, though.

In order to avoid this keep three different flags for each event channel
to be able to distinguish "normal" masking/unmasking from eoi related
masking/unmasking and temporary masking. The event channel should only
be able to generate an interrupt if all flags are cleared.

Cc: stable@vger.kernel.org
Fixes: 54c9de8989 ("xen/events: add a new "late EOI" evtchn framework")
Reported-by: Julien Grall <julien@xen.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Link: https://lore.kernel.org/r/20210306161833.4552-3-jgross@suse.com

[boris -- corrected Fixed tag format]

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-03-10 16:37:29 -06:00

111 lines
2.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Xen Event Channels (internal header)
*
* Copyright (C) 2013 Citrix Systems R&D Ltd.
*/
#ifndef __EVENTS_INTERNAL_H__
#define __EVENTS_INTERNAL_H__
struct evtchn_loop_ctrl;
struct evtchn_ops {
unsigned (*max_channels)(void);
unsigned (*nr_channels)(void);
int (*setup)(evtchn_port_t port);
void (*remove)(evtchn_port_t port, unsigned int cpu);
void (*bind_to_cpu)(evtchn_port_t evtchn, unsigned int cpu,
unsigned int old_cpu);
void (*clear_pending)(evtchn_port_t port);
void (*set_pending)(evtchn_port_t port);
bool (*is_pending)(evtchn_port_t port);
void (*mask)(evtchn_port_t port);
void (*unmask)(evtchn_port_t port);
void (*handle_events)(unsigned cpu, struct evtchn_loop_ctrl *ctrl);
void (*resume)(void);
int (*percpu_init)(unsigned int cpu);
int (*percpu_deinit)(unsigned int cpu);
};
extern const struct evtchn_ops *evtchn_ops;
int get_evtchn_to_irq(evtchn_port_t evtchn);
void handle_irq_for_port(evtchn_port_t port, struct evtchn_loop_ctrl *ctrl);
unsigned int cpu_from_evtchn(evtchn_port_t evtchn);
static inline unsigned xen_evtchn_max_channels(void)
{
return evtchn_ops->max_channels();
}
/*
* Do any ABI specific setup for a bound event channel before it can
* be unmasked and used.
*/
static inline int xen_evtchn_port_setup(evtchn_port_t evtchn)
{
if (evtchn_ops->setup)
return evtchn_ops->setup(evtchn);
return 0;
}
static inline void xen_evtchn_port_remove(evtchn_port_t evtchn,
unsigned int cpu)
{
if (evtchn_ops->remove)
evtchn_ops->remove(evtchn, cpu);
}
static inline void xen_evtchn_port_bind_to_cpu(evtchn_port_t evtchn,
unsigned int cpu,
unsigned int old_cpu)
{
evtchn_ops->bind_to_cpu(evtchn, cpu, old_cpu);
}
static inline void clear_evtchn(evtchn_port_t port)
{
evtchn_ops->clear_pending(port);
}
static inline void set_evtchn(evtchn_port_t port)
{
evtchn_ops->set_pending(port);
}
static inline bool test_evtchn(evtchn_port_t port)
{
return evtchn_ops->is_pending(port);
}
static inline void mask_evtchn(evtchn_port_t port)
{
return evtchn_ops->mask(port);
}
static inline void unmask_evtchn(evtchn_port_t port)
{
return evtchn_ops->unmask(port);
}
static inline void xen_evtchn_handle_events(unsigned cpu,
struct evtchn_loop_ctrl *ctrl)
{
return evtchn_ops->handle_events(cpu, ctrl);
}
static inline void xen_evtchn_resume(void)
{
if (evtchn_ops->resume)
evtchn_ops->resume();
}
void xen_evtchn_2l_init(void);
int xen_evtchn_fifo_init(void);
#endif /* #ifndef __EVENTS_INTERNAL_H__ */