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vhost-vdpa: batch updating IOTLB mappings

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To speed up the memory mapping updating between vhost-vDPA and vDPA
device driver, this patch passes the IOTLB batching flags via IOTLB
API. Two new flags was introduced, VHOST_IOTLB_BATCH_BEGIN is a hint
that a bathced IOTLB updating may be initiated from the
userspace. VHOST_IOTLB_BATCH_END is a hint that userspace has finished
the updating:

VHOST_IOTLB_BATCH_BEGIN
VHOST_IOTLB_UPDATE/VHOST_IOTLB_INVALIDATE
...
VHOST_IOTLB_BATCH_END

Vhost-vDPA can then know that all mappings has been set and can do
optimization like passing all the mappings to the vDPA device driver.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20200907104903.31551-4-jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Jason Wang
2020-09-07 18:49:03 +08:00
committed by Michael S. Tsirkin
parent b37556edec
commit a5bd05800f
2 changed files with 67 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

66
hw/virtio/vhost-vdpa.c
View File

@@ -78,6 +78,46 @@ static int vhost_vdpa_dma_unmap(struct vhost_vdpa *v, hwaddr iova,
return ret;
}
static void vhost_vdpa_listener_begin(MemoryListener *listener)
{
struct vhost_vdpa *v = container_of(listener, struct vhost_vdpa, listener);
struct vhost_dev *dev = v->dev;
struct vhost_msg_v2 msg;
int fd = v->device_fd;
if (!(dev->backend_cap & (0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH))) {
return;
}
msg.type = v->msg_type;
msg.iotlb.type = VHOST_IOTLB_BATCH_BEGIN;
if (write(fd, &msg, sizeof(msg)) != sizeof(msg)) {
error_report("failed to write, fd=%d, errno=%d (%s)",
fd, errno, strerror(errno));
}
}
static void vhost_vdpa_listener_commit(MemoryListener *listener)
{
struct vhost_vdpa *v = container_of(listener, struct vhost_vdpa, listener);
struct vhost_dev *dev = v->dev;
struct vhost_msg_v2 msg;
int fd = v->device_fd;
if (!(dev->backend_cap & (0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH))) {
return;
}
msg.type = v->msg_type;
msg.iotlb.type = VHOST_IOTLB_BATCH_END;
if (write(fd, &msg, sizeof(msg)) != sizeof(msg)) {
error_report("failed to write, fd=%d, errno=%d (%s)",
fd, errno, strerror(errno));
}
}
static void vhost_vdpa_listener_region_add(MemoryListener *listener,
MemoryRegionSection *section)
{
@@ -188,6 +228,8 @@ static void vhost_vdpa_listener_region_del(MemoryListener *listener,
* depends on the addnop().
*/
static const MemoryListener vhost_vdpa_memory_listener = {
.begin = vhost_vdpa_listener_begin,
.commit = vhost_vdpa_listener_commit,
.region_add = vhost_vdpa_listener_region_add,
.region_del = vhost_vdpa_listener_region_del,
};
@@ -223,6 +265,7 @@ static int vhost_vdpa_init(struct vhost_dev *dev, void *opaque)
assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_VDPA);
v = opaque;
v->dev = dev;
dev->opaque = opaque ;
vhost_vdpa_call(dev, VHOST_GET_FEATURES, &features);
dev->backend_features = features;
@@ -277,6 +320,28 @@ static int vhost_vdpa_set_features(struct vhost_dev *dev,
return !(status & VIRTIO_CONFIG_S_FEATURES_OK);
}
static int vhost_vdpa_set_backend_cap(struct vhost_dev *dev)
{
uint64_t features;
uint64_t f = 0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2 |
0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH;
int r;
if (vhost_vdpa_call(dev, VHOST_GET_BACKEND_FEATURES, &features)) {
return 0;
}
features &= f;
r = vhost_vdpa_call(dev, VHOST_SET_BACKEND_FEATURES, &features);
if (r) {
return 0;
}
dev->backend_cap = features;
return 0;
}
int vhost_vdpa_get_device_id(struct vhost_dev *dev,
uint32_t *device_id)
{
@@ -444,6 +509,7 @@ const VhostOps vdpa_ops = {
.vhost_set_vring_kick = vhost_vdpa_set_vring_kick,
.vhost_set_vring_call = vhost_vdpa_set_vring_call,
.vhost_get_features = vhost_vdpa_get_features,
.vhost_set_backend_cap = vhost_vdpa_set_backend_cap,
.vhost_set_owner = vhost_vdpa_set_owner,
.vhost_set_vring_endian = NULL,
.vhost_backend_memslots_limit = vhost_vdpa_memslots_limit,

1
include/hw/virtio/vhost-vdpa.h
View File

@@ -18,6 +18,7 @@ typedef struct vhost_vdpa {
int device_fd;
uint32_t msg_type;
MemoryListener listener;
struct vhost_dev *dev;
} VhostVDPA;
extern AddressSpace address_space_memory;