linux/arch/x86/kvm/i8254.h
Radim Krčmář a0aace5ac0 KVM: i8254: turn kvm_kpit_state.reinject into atomic_t
Document possible races between readers and concurrent update to the
ioctl.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-04 09:30:25 +01:00

67 lines
1.5 KiB
C

#ifndef __I8254_H
#define __I8254_H
#include <linux/kthread.h>
#include <kvm/iodev.h>
struct kvm_kpit_channel_state {
u32 count; /* can be 65536 */
u16 latched_count;
u8 count_latched;
u8 status_latched;
u8 status;
u8 read_state;
u8 write_state;
u8 write_latch;
u8 rw_mode;
u8 mode;
u8 bcd; /* not supported */
u8 gate; /* timer start */
ktime_t count_load_time;
};
struct kvm_kpit_state {
/* All members before "struct mutex lock" are protected by the lock. */
struct kvm_kpit_channel_state channels[3];
u32 flags;
bool is_periodic;
s64 period; /* unit: ns */
struct hrtimer timer;
u32 speaker_data_on;
struct mutex lock;
atomic_t reinject;
atomic_t pending; /* accumulated triggered timers */
atomic_t irq_ack;
struct kvm_irq_ack_notifier irq_ack_notifier;
};
struct kvm_pit {
struct kvm_io_device dev;
struct kvm_io_device speaker_dev;
struct kvm *kvm;
struct kvm_kpit_state pit_state;
int irq_source_id;
struct kvm_irq_mask_notifier mask_notifier;
struct kthread_worker worker;
struct task_struct *worker_task;
struct kthread_work expired;
};
#define KVM_PIT_BASE_ADDRESS 0x40
#define KVM_SPEAKER_BASE_ADDRESS 0x61
#define KVM_PIT_MEM_LENGTH 4
#define KVM_PIT_FREQ 1193181
#define KVM_MAX_PIT_INTR_INTERVAL HZ / 100
#define KVM_PIT_CHANNEL_MASK 0x3
struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags);
void kvm_free_pit(struct kvm *kvm);
void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
int hpet_legacy_start);
void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject);
#endif