This patch add the capability of basic vhost net busy polling which is supported by recent kernel. User could configure the maximum number of us that could be spent on busy polling through a new property of tap "poll-us". Cc: Greg Kurz <groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
221 lines
6.9 KiB
C
221 lines
6.9 KiB
C
/*
|
|
* vhost-backend
|
|
*
|
|
* Copyright (c) 2013 Virtual Open Systems Sarl.
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2 or later.
|
|
* See the COPYING file in the top-level directory.
|
|
*
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "hw/virtio/vhost.h"
|
|
#include "hw/virtio/vhost-backend.h"
|
|
#include "qemu/error-report.h"
|
|
#include "linux/vhost.h"
|
|
|
|
#include <sys/ioctl.h>
|
|
|
|
static int vhost_kernel_call(struct vhost_dev *dev, unsigned long int request,
|
|
void *arg)
|
|
{
|
|
int fd = (uintptr_t) dev->opaque;
|
|
|
|
assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
|
|
|
|
return ioctl(fd, request, arg);
|
|
}
|
|
|
|
static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
|
|
{
|
|
assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
|
|
|
|
dev->opaque = opaque;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int vhost_kernel_cleanup(struct vhost_dev *dev)
|
|
{
|
|
int fd = (uintptr_t) dev->opaque;
|
|
|
|
assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
|
|
|
|
return close(fd);
|
|
}
|
|
|
|
static int vhost_kernel_memslots_limit(struct vhost_dev *dev)
|
|
{
|
|
int limit = 64;
|
|
char *s;
|
|
|
|
if (g_file_get_contents("/sys/module/vhost/parameters/max_mem_regions",
|
|
&s, NULL, NULL)) {
|
|
uint64_t val = g_ascii_strtoull(s, NULL, 10);
|
|
if (!((val == G_MAXUINT64 || !val) && errno)) {
|
|
return val;
|
|
}
|
|
error_report("ignoring invalid max_mem_regions value in vhost module:"
|
|
" %s", s);
|
|
}
|
|
return limit;
|
|
}
|
|
|
|
static int vhost_kernel_net_set_backend(struct vhost_dev *dev,
|
|
struct vhost_vring_file *file)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_NET_SET_BACKEND, file);
|
|
}
|
|
|
|
static int vhost_kernel_scsi_set_endpoint(struct vhost_dev *dev,
|
|
struct vhost_scsi_target *target)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SCSI_SET_ENDPOINT, target);
|
|
}
|
|
|
|
static int vhost_kernel_scsi_clear_endpoint(struct vhost_dev *dev,
|
|
struct vhost_scsi_target *target)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SCSI_CLEAR_ENDPOINT, target);
|
|
}
|
|
|
|
static int vhost_kernel_scsi_get_abi_version(struct vhost_dev *dev, int *version)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SCSI_GET_ABI_VERSION, version);
|
|
}
|
|
|
|
static int vhost_kernel_set_log_base(struct vhost_dev *dev, uint64_t base,
|
|
struct vhost_log *log)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_LOG_BASE, &base);
|
|
}
|
|
|
|
static int vhost_kernel_set_mem_table(struct vhost_dev *dev,
|
|
struct vhost_memory *mem)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_MEM_TABLE, mem);
|
|
}
|
|
|
|
static int vhost_kernel_set_vring_addr(struct vhost_dev *dev,
|
|
struct vhost_vring_addr *addr)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_VRING_ADDR, addr);
|
|
}
|
|
|
|
static int vhost_kernel_set_vring_endian(struct vhost_dev *dev,
|
|
struct vhost_vring_state *ring)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_VRING_ENDIAN, ring);
|
|
}
|
|
|
|
static int vhost_kernel_set_vring_num(struct vhost_dev *dev,
|
|
struct vhost_vring_state *ring)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_VRING_NUM, ring);
|
|
}
|
|
|
|
static int vhost_kernel_set_vring_base(struct vhost_dev *dev,
|
|
struct vhost_vring_state *ring)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_VRING_BASE, ring);
|
|
}
|
|
|
|
static int vhost_kernel_get_vring_base(struct vhost_dev *dev,
|
|
struct vhost_vring_state *ring)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_GET_VRING_BASE, ring);
|
|
}
|
|
|
|
static int vhost_kernel_set_vring_kick(struct vhost_dev *dev,
|
|
struct vhost_vring_file *file)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_VRING_KICK, file);
|
|
}
|
|
|
|
static int vhost_kernel_set_vring_call(struct vhost_dev *dev,
|
|
struct vhost_vring_file *file)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_VRING_CALL, file);
|
|
}
|
|
|
|
static int vhost_kernel_set_vring_busyloop_timeout(struct vhost_dev *dev,
|
|
struct vhost_vring_state *s)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_VRING_BUSYLOOP_TIMEOUT, s);
|
|
}
|
|
|
|
static int vhost_kernel_set_features(struct vhost_dev *dev,
|
|
uint64_t features)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_FEATURES, &features);
|
|
}
|
|
|
|
static int vhost_kernel_get_features(struct vhost_dev *dev,
|
|
uint64_t *features)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_GET_FEATURES, features);
|
|
}
|
|
|
|
static int vhost_kernel_set_owner(struct vhost_dev *dev)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_SET_OWNER, NULL);
|
|
}
|
|
|
|
static int vhost_kernel_reset_device(struct vhost_dev *dev)
|
|
{
|
|
return vhost_kernel_call(dev, VHOST_RESET_OWNER, NULL);
|
|
}
|
|
|
|
static int vhost_kernel_get_vq_index(struct vhost_dev *dev, int idx)
|
|
{
|
|
assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs);
|
|
|
|
return idx - dev->vq_index;
|
|
}
|
|
|
|
static const VhostOps kernel_ops = {
|
|
.backend_type = VHOST_BACKEND_TYPE_KERNEL,
|
|
.vhost_backend_init = vhost_kernel_init,
|
|
.vhost_backend_cleanup = vhost_kernel_cleanup,
|
|
.vhost_backend_memslots_limit = vhost_kernel_memslots_limit,
|
|
.vhost_net_set_backend = vhost_kernel_net_set_backend,
|
|
.vhost_scsi_set_endpoint = vhost_kernel_scsi_set_endpoint,
|
|
.vhost_scsi_clear_endpoint = vhost_kernel_scsi_clear_endpoint,
|
|
.vhost_scsi_get_abi_version = vhost_kernel_scsi_get_abi_version,
|
|
.vhost_set_log_base = vhost_kernel_set_log_base,
|
|
.vhost_set_mem_table = vhost_kernel_set_mem_table,
|
|
.vhost_set_vring_addr = vhost_kernel_set_vring_addr,
|
|
.vhost_set_vring_endian = vhost_kernel_set_vring_endian,
|
|
.vhost_set_vring_num = vhost_kernel_set_vring_num,
|
|
.vhost_set_vring_base = vhost_kernel_set_vring_base,
|
|
.vhost_get_vring_base = vhost_kernel_get_vring_base,
|
|
.vhost_set_vring_kick = vhost_kernel_set_vring_kick,
|
|
.vhost_set_vring_call = vhost_kernel_set_vring_call,
|
|
.vhost_set_vring_busyloop_timeout =
|
|
vhost_kernel_set_vring_busyloop_timeout,
|
|
.vhost_set_features = vhost_kernel_set_features,
|
|
.vhost_get_features = vhost_kernel_get_features,
|
|
.vhost_set_owner = vhost_kernel_set_owner,
|
|
.vhost_reset_device = vhost_kernel_reset_device,
|
|
.vhost_get_vq_index = vhost_kernel_get_vq_index,
|
|
};
|
|
|
|
int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType backend_type)
|
|
{
|
|
int r = 0;
|
|
|
|
switch (backend_type) {
|
|
case VHOST_BACKEND_TYPE_KERNEL:
|
|
dev->vhost_ops = &kernel_ops;
|
|
break;
|
|
case VHOST_BACKEND_TYPE_USER:
|
|
dev->vhost_ops = &user_ops;
|
|
break;
|
|
default:
|
|
error_report("Unknown vhost backend type");
|
|
r = -1;
|
|
}
|
|
|
|
return r;
|
|
}
|