在 2022/8/4 01:18, Eugenio Pérez 写道:
Isolate control virtqueue in its own group, allowing to intercept control
commands but letting dataplane run totally passthrough to the guest.
Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
---
v3:
* Make asid related queries print a warning instead of returning an
error and stop the start of qemu.
---
hw/virtio/vhost-vdpa.c | 3 +-
net/vhost-vdpa.c | 144 +++++++++++++++++++++++++++++++++++++++--
2 files changed, 142 insertions(+), 5 deletions(-)
diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 131100841c..a4cb68862b 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -674,7 +674,8 @@ 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;
+ 0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH |
+ 0x1ULL << VHOST_BACKEND_F_IOTLB_ASID;
int r;
if (vhost_vdpa_call(dev, VHOST_GET_BACKEND_FEATURES, &features)) {
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index e3b65ed546..5f39f0edb5 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -37,6 +37,9 @@ typedef struct VhostVDPAState {
/* Control commands shadow buffers */
void *cvq_cmd_out_buffer, *cvq_cmd_in_buffer;
+ /* Number of address spaces supported by the device */
+ unsigned address_space_num;
+
/* The device always have SVQ enabled */
bool always_svq;
bool started;
@@ -100,6 +103,8 @@ static const uint64_t vdpa_svq_device_features =
BIT_ULL(VIRTIO_NET_F_RSC_EXT) |
BIT_ULL(VIRTIO_NET_F_STANDBY);
+#define VHOST_VDPA_NET_CVQ_ASID 1
+
VHostNetState *vhost_vdpa_get_vhost_net(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
@@ -224,6 +229,101 @@ static NetClientInfo net_vhost_vdpa_info = {
.check_peer_type = vhost_vdpa_check_peer_type,
};
+static void vhost_vdpa_get_vring_group(int device_fd,
+ struct vhost_vring_state *state)
+{
+ int r = ioctl(device_fd, VHOST_VDPA_GET_VRING_GROUP, state);
+ if (unlikely(r < 0)) {
+ /*
+ * Assume all groups are 0, the consequences are the same and we will
+ * not abort device creation
+ */
+ state->num = 0;
+ }
+}
+
+/**
+ * Check if all the virtqueues of the virtio device are in a different vq than
+ * the last vq. VQ group of last group passed in cvq_group.
+ */
+static bool vhost_vdpa_cvq_group_is_independent(struct vhost_vdpa *v,
+ struct vhost_vring_state cvq_group)
+{
+ struct vhost_dev *dev = v->dev;
+
+ for (int i = 0; i < (dev->vq_index_end - 1); ++i) {
+ struct vhost_vring_state vq_group = {
+ .index = i,
+ };
+
+ vhost_vdpa_get_vring_group(v->device_fd, &vq_group);
+ if (unlikely(vq_group.num == cvq_group.num)) {
+ warn_report("CVQ %u group is the same as VQ %u one (%u)",
+ cvq_group.index, vq_group.index, cvq_group.num);
I don't get why we need warn here.
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static int vhost_vdpa_set_address_space_id(struct vhost_vdpa *v,
+ unsigned vq_group,
+ unsigned asid_num)
+{
+ struct vhost_vring_state asid = {
+ .index = vq_group,
+ .num = asid_num,
+ };
+ int ret;
+
+ ret = ioctl(v->device_fd, VHOST_VDPA_SET_GROUP_ASID, &asid);
+ if (unlikely(ret < 0)) {
+ warn_report("Can't set vq group %u asid %u, errno=%d (%s)",
+ asid.index, asid.num, errno, g_strerror(errno));
+ }
+ return ret;
+}
+
+static void vhost_vdpa_net_prepare(NetClientState *nc)
+{
+ VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
+ struct vhost_vdpa *v = &s->vhost_vdpa;
+ struct vhost_dev *dev = v->dev;
+ struct vhost_vring_state cvq_group = {
+ .index = v->dev->vq_index_end - 1,
+ };
+ int r;
+
+ assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
+
+ if (dev->nvqs != 1 || dev->vq_index + dev->nvqs != dev->vq_index_end) {
+ /* Only interested in CVQ */
+ return;
+ }
+
+ if (s->always_svq) {
+ /* SVQ is already enabled */
+ return;
+ }
+
+ if (s->address_space_num < 2) {
+ v->shadow_vqs_enabled = false;
+ return;
+ }
+
+ vhost_vdpa_get_vring_group(v->device_fd, &cvq_group);
+ if (!vhost_vdpa_cvq_group_is_independent(v, cvq_group)) {
If there's no other caller of vhost_vdpa_cvq_group_is_independent(), I'd
suggest to unitfy them into a single helper.
(Btw, the name of the function is kind of too long).
Thanks
+ v->shadow_vqs_enabled = false;
+ return;
+ }
+
+ r = vhost_vdpa_set_address_space_id(v, cvq_group.num,
+ VHOST_VDPA_NET_CVQ_ASID);
+ v->shadow_vqs_enabled = r == 0;
+ s->vhost_vdpa.address_space_id = r == 0 ? 1 : 0;
+}
+
static void vhost_vdpa_cvq_unmap_buf(struct vhost_vdpa *v, void *addr)
{
VhostIOVATree *tree = v->iova_tree;
@@ -431,6 +531,7 @@ static NetClientInfo net_vhost_vdpa_cvq_info = {
.type = NET_CLIENT_DRIVER_VHOST_VDPA,
.size = sizeof(VhostVDPAState),
.receive = vhost_vdpa_receive,
+ .prepare = vhost_vdpa_net_prepare,
.load = vhost_vdpa_net_load,
.cleanup = vhost_vdpa_cleanup,
.has_vnet_hdr = vhost_vdpa_has_vnet_hdr,
@@ -541,12 +642,38 @@ static const VhostShadowVirtqueueOps vhost_vdpa_net_svq_ops = {
.avail_handler = vhost_vdpa_net_handle_ctrl_avail,
};
+static uint32_t vhost_vdpa_get_as_num(int vdpa_device_fd)
+{
+ uint64_t features;
+ unsigned num_as;
+ int r;
+
+ r = ioctl(vdpa_device_fd, VHOST_GET_BACKEND_FEATURES, &features);
+ if (unlikely(r < 0)) {
+ warn_report("Cannot get backend features");
+ return 1;
+ }
+
+ if (!(features & BIT_ULL(VHOST_BACKEND_F_IOTLB_ASID))) {
+ return 1;
+ }
+
+ r = ioctl(vdpa_device_fd, VHOST_VDPA_GET_AS_NUM, &num_as);
+ if (unlikely(r < 0)) {
+ warn_report("Cannot retrieve number of supported ASs");
+ return 1;
+ }
+
+ return num_as;
+}
+
static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
const char *device,
const char *name,
int vdpa_device_fd,
int queue_pair_index,
int nvqs,
+ unsigned nas,
bool is_datapath,
bool svq,
VhostIOVATree *iova_tree)
@@ -565,6 +692,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
snprintf(nc->info_str, sizeof(nc->info_str), TYPE_VHOST_VDPA);
s = DO_UPCAST(VhostVDPAState, nc, nc);
+ s->address_space_num = nas;
s->vhost_vdpa.device_fd = vdpa_device_fd;
s->vhost_vdpa.index = queue_pair_index;
s->always_svq = svq;
@@ -650,6 +778,8 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
g_autoptr(VhostIOVATree) iova_tree = NULL;
NetClientState *nc;
int queue_pairs, r, i = 0, has_cvq = 0;
+ unsigned num_as = 1;
+ bool svq_cvq;
assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA);
opts = &netdev->u.vhost_vdpa;
@@ -674,7 +804,13 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
goto err;
}
- if (opts->x_svq) {
+ svq_cvq = opts->x_svq;
+ if (has_cvq && !opts->x_svq) {
+ num_as = vhost_vdpa_get_as_num(vdpa_device_fd);
+ svq_cvq = num_as > 1;
+ }
+
+ if (opts->x_svq || svq_cvq) {
struct vhost_vdpa_iova_range iova_range;
uint64_t invalid_dev_features =
@@ -697,15 +833,15 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
for (i = 0; i < queue_pairs; i++) {
ncs[i] = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
- vdpa_device_fd, i, 2, true, opts->x_svq,
- iova_tree);
+ vdpa_device_fd, i, 2, num_as, true,
+ opts->x_svq, iova_tree);
if (!ncs[i])
goto err;
}
if (has_cvq) {
nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
- vdpa_device_fd, i, 1, false,
+ vdpa_device_fd, i, 1, num_as, false,
opts->x_svq, iova_tree);
if (!nc)
goto err;
