kvm: add API to set ioeventfd

Comment on kvm usage: rather than require users to do if (kvm_enabled())
and/or ifdefs, this patch adds an API that, internally, is defined to
stub function on non-kvm build, and checks kvm_enabled for non-kvm
run.

While rest of qemu code still uses if (kvm_enabled()), I think this
approach is cleaner, and we should convert rest of code to it
long term.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Michael S. Tsirkin 2010-03-17 13:07:54 +02:00 committed by Anthony Liguori
parent 95d528a2fe
commit ca82180603
2 changed files with 39 additions and 1 deletions

View File

@ -1151,3 +1151,25 @@ int kvm_set_signal_mask(CPUState *env, const sigset_t *sigset)
return r;
}
#ifdef KVM_IOEVENTFD
int kvm_set_ioeventfd_pio_word(int fd, uint16_t addr, uint16_t val, bool assign)
{
struct kvm_ioeventfd kick = {
.datamatch = val,
.addr = addr,
.len = 2,
.flags = KVM_IOEVENTFD_FLAG_DATAMATCH | KVM_IOEVENTFD_FLAG_PIO,
.fd = fd,
};
int r;
if (!kvm_enabled())
return -ENOSYS;
if (!assign)
kick.flags |= KVM_IOEVENTFD_FLAG_DEASSIGN;
r = kvm_vm_ioctl(kvm_state, KVM_IOEVENTFD, &kick);
if (r < 0)
return r;
return 0;
}
#endif

18
kvm.h
View File

@ -14,12 +14,17 @@
#ifndef QEMU_KVM_H
#define QEMU_KVM_H
#include <stdbool.h>
#include <errno.h>
#include "config-host.h"
#include "qemu-queue.h"
extern int kvm_allowed;
#ifdef CONFIG_KVM
#include <linux/kvm.h>
#endif
#ifdef CONFIG_KVM
extern int kvm_allowed;
#define kvm_enabled() (kvm_allowed)
#else
#define kvm_enabled() (0)
@ -161,5 +166,16 @@ static inline void cpu_synchronize_post_init(CPUState *env)
kvm_cpu_synchronize_post_init(env);
}
}
#if defined(KVM_IOEVENTFD) && defined(CONFIG_KVM)
int kvm_set_ioeventfd_pio_word(int fd, uint16_t adr, uint16_t val, bool assign);
#else
static inline
int kvm_set_ioeventfd_pio_word(int fd, uint16_t adr, uint16_t val, bool assign)
{
return -ENOSYS;
}
#endif
#endif
#endif