qemu/hw/vhost.h
Jason Wang a9f98bb5eb vhost: multiqueue support
This patch lets vhost support multiqueue. The idea is simple, just launching
multiple threads of vhost and let each of vhost thread processing a subset of
the virtqueues of the device. After this change each emulated device can have
multiple vhost threads as its backend.

To do this, a virtqueue index were introduced to record to first virtqueue that
will be handled by this vhost_net device. Based on this and nvqs, vhost could
calculate its relative index to setup vhost_net device.

Since we may have many vhost/net devices for a virtio-net device. The setting of
guest notifiers were moved out of the starting/stopping of a specific vhost
thread. The vhost_net_{start|stop}() were renamed to
vhost_net_{start|stop}_one(), and a new vhost_net_{start|stop}() were introduced
to configure the guest notifiers and start/stop all vhost/vhost_net devices.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-01 11:03:02 -06:00

68 lines
2 KiB
C

#ifndef VHOST_H
#define VHOST_H
#include "hw/hw.h"
#include "hw/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)
struct vhost_memory;
struct vhost_dev {
MemoryListener memory_listener;
int control;
struct vhost_memory *mem;
int n_mem_sections;
MemoryRegionSection *mem_sections;
struct vhost_virtqueue *vqs;
int nvqs;
/* the first virtuque 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;
vhost_log_chunk_t *log;
unsigned long long log_size;
bool force;
};
int vhost_dev_init(struct vhost_dev *hdev, int devfd, const char *devpath,
bool force);
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);
#endif