qemu/include/hw/virtio/vhost.h
Pankaj Gupta 1e7398a140 vhost: enable vhost without without MSI-X
We use vhostforce to enable vhost even if Guests don't have MSI-X
support and we fall back to QEMU virtio-net.

This gives a very small performance gain, but the disadvantage
is that guest now controls which virtio code is running
(qemu or vhost) so our attack surface is doubled.

This patch will enable vhost unconditionally whenever it's requested.
For compatibility, enable vhost when vhostforce is set, as well.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
2015-06-19 12:17:49 +02:00

85 lines
2.5 KiB
C

#ifndef VHOST_H
#define VHOST_H
#include "hw/hw.h"
#include "hw/virtio/vhost-backend.h"
#include "hw/virtio/virtio.h"
#include "exec/memory.h"
/* Generic structures common for any vhost based device. */
struct vhost_virtqueue {
int kick;
int call;
void *desc;
void *avail;
void *used;
int num;
unsigned long long used_phys;
unsigned used_size;
void *ring;
unsigned long long ring_phys;
unsigned ring_size;
EventNotifier masked_notifier;
};
typedef unsigned long vhost_log_chunk_t;
#define VHOST_LOG_PAGE 0x1000
#define VHOST_LOG_BITS (8 * sizeof(vhost_log_chunk_t))
#define VHOST_LOG_CHUNK (VHOST_LOG_PAGE * VHOST_LOG_BITS)
#define VHOST_INVALID_FEATURE_BIT (0xff)
struct vhost_log {
unsigned long long size;
int refcnt;
vhost_log_chunk_t log[0];
};
struct vhost_memory;
struct vhost_dev {
MemoryListener memory_listener;
struct vhost_memory *mem;
int n_mem_sections;
MemoryRegionSection *mem_sections;
struct vhost_virtqueue *vqs;
int nvqs;
/* the first virtqueue which would be used by this vhost dev */
int vq_index;
unsigned long long features;
unsigned long long acked_features;
unsigned long long backend_features;
bool started;
bool log_enabled;
unsigned long long log_size;
Error *migration_blocker;
bool memory_changed;
hwaddr mem_changed_start_addr;
hwaddr mem_changed_end_addr;
const VhostOps *vhost_ops;
void *opaque;
struct vhost_log *log;
};
int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
VhostBackendType backend_type);
void vhost_dev_cleanup(struct vhost_dev *hdev);
bool vhost_dev_query(struct vhost_dev *hdev, VirtIODevice *vdev);
int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev);
void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev);
int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev);
void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev);
/* Test and clear masked event pending status.
* Should be called after unmask to avoid losing events.
*/
bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n);
/* Mask/unmask events from this vq.
*/
void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n,
bool mask);
uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits,
uint64_t features);
void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits,
uint64_t features);
#endif