| Message ID | 20230224155438.112797-2-eperezma@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Dynamically switch to vhost shadow virtqueues at vdpa net migration | expand |
在 2023/2/24 23:54, Eugenio Pérez 写道: > Only create iova_tree if and when it is needed. > > The cleanup keeps being responsible of last VQ but this change allows it > to merge both cleanup functions. > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > Acked-by: Jason Wang <jasowang@redhat.com> > --- > v4: > * Remove leak of iova_tree because double allocation > * Document better the sharing of IOVA tree between data and CVQ > --- > net/vhost-vdpa.c | 113 ++++++++++++++++++++++++++++++++++------------- > 1 file changed, 83 insertions(+), 30 deletions(-) > > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c > index de5ed8ff22..b89c99066a 100644 > --- a/net/vhost-vdpa.c > +++ b/net/vhost-vdpa.c > @@ -178,13 +178,9 @@ err_init: > static void vhost_vdpa_cleanup(NetClientState *nc) > { > VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > - struct vhost_dev *dev = &s->vhost_net->dev; > > qemu_vfree(s->cvq_cmd_out_buffer); > qemu_vfree(s->status); > - if (dev->vq_index + dev->nvqs == dev->vq_index_end) { > - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > - } > if (s->vhost_net) { > vhost_net_cleanup(s->vhost_net); > g_free(s->vhost_net); > @@ -234,10 +230,64 @@ static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf, > return size; > } > > +/** From any vdpa net client, get the netclient of first queue pair */ > +static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s) > +{ > + NICState *nic = qemu_get_nic(s->nc.peer); > + NetClientState *nc0 = qemu_get_peer(nic->ncs, 0); > + > + return DO_UPCAST(VhostVDPAState, nc, nc0); > +} > + > +static void vhost_vdpa_net_data_start_first(VhostVDPAState *s) > +{ > + struct vhost_vdpa *v = &s->vhost_vdpa; > + > + if (v->shadow_vqs_enabled) { > + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > + v->iova_range.last); > + } > +} > + > +static int vhost_vdpa_net_data_start(NetClientState *nc) > +{ > + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > + struct vhost_vdpa *v = &s->vhost_vdpa; > + > + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); > + > + if (v->index == 0) { > + vhost_vdpa_net_data_start_first(s); > + return 0; > + } > + > + if (v->shadow_vqs_enabled) { > + VhostVDPAState *s0 = vhost_vdpa_net_first_nc_vdpa(s); > + v->iova_tree = s0->vhost_vdpa.iova_tree; > + } > + > + return 0; > +} > + > +static void vhost_vdpa_net_client_stop(NetClientState *nc) > +{ > + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > + struct vhost_dev *dev; > + > + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); > + > + dev = s->vhost_vdpa.dev; > + if (dev->vq_index + dev->nvqs == dev->vq_index_end) { > + g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > + } > +} > + > static NetClientInfo net_vhost_vdpa_info = { > .type = NET_CLIENT_DRIVER_VHOST_VDPA, > .size = sizeof(VhostVDPAState), > .receive = vhost_vdpa_receive, > + .start = vhost_vdpa_net_data_start, > + .stop = vhost_vdpa_net_client_stop, Looking at the implementation, it seems nothing net specific, any reason we can't simply use vhost_vdpa_dev_start()? > .cleanup = vhost_vdpa_cleanup, > .has_vnet_hdr = vhost_vdpa_has_vnet_hdr, > .has_ufo = vhost_vdpa_has_ufo, > @@ -351,7 +401,7 @@ dma_map_err: > > static int vhost_vdpa_net_cvq_start(NetClientState *nc) > { > - VhostVDPAState *s; > + VhostVDPAState *s, *s0; > struct vhost_vdpa *v; > uint64_t backend_features; > int64_t cvq_group; > @@ -415,8 +465,6 @@ static int vhost_vdpa_net_cvq_start(NetClientState *nc) > return r; > } > > - v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > - v->iova_range.last); > v->shadow_vqs_enabled = true; > s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID; > > @@ -425,6 +473,27 @@ out: > return 0; > } > > + s0 = vhost_vdpa_net_first_nc_vdpa(s); > + if (s0->vhost_vdpa.iova_tree) { > + /* > + * SVQ is already configured for all virtqueues. Reuse IOVA tree for > + * simplicity, wether CVQ shares ASID with guest or not, because: Typo, should be "whether", or "regardless of whether"(not a native speaker). Other looks good. Thanks > + * - Memory listener need access to guest's memory addresses allocated > + * in the IOVA tree. > + * - There should be plenty of IOVA address space for both ASID not to > + * worry about collisions between them. Guest's translations are > + * still validated with virtio virtqueue_pop so there is no risk for > + * the guest to access memory it shouldn't. > + * > + * To allocate a iova tree per ASID is doable but it complicates the > + * code and it is not worth for the moment. > + */ > + v->iova_tree = s0->vhost_vdpa.iova_tree; > + } else { > + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > + v->iova_range.last); > + } > + > r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer, > vhost_vdpa_net_cvq_cmd_page_len(), false); > if (unlikely(r < 0)) { > @@ -449,15 +518,9 @@ static void vhost_vdpa_net_cvq_stop(NetClientState *nc) > if (s->vhost_vdpa.shadow_vqs_enabled) { > vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer); > vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status); > - if (!s->always_svq) { > - /* > - * If only the CVQ is shadowed we can delete this safely. > - * If all the VQs are shadows this will be needed by the time the > - * device is started again to register SVQ vrings and similar. > - */ > - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > - } > } > + > + vhost_vdpa_net_client_stop(nc); > } > > static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, size_t out_len, > @@ -667,8 +730,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, > int nvqs, > bool is_datapath, > bool svq, > - struct vhost_vdpa_iova_range iova_range, > - VhostIOVATree *iova_tree) > + struct vhost_vdpa_iova_range iova_range) > { > NetClientState *nc = NULL; > VhostVDPAState *s; > @@ -690,7 +752,6 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, > s->vhost_vdpa.shadow_vqs_enabled = svq; > s->vhost_vdpa.iova_range = iova_range; > s->vhost_vdpa.shadow_data = svq; > - s->vhost_vdpa.iova_tree = iova_tree; > if (!is_datapath) { > s->cvq_cmd_out_buffer = qemu_memalign(qemu_real_host_page_size(), > vhost_vdpa_net_cvq_cmd_page_len()); > @@ -760,7 +821,6 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > uint64_t features; > int vdpa_device_fd; > g_autofree NetClientState **ncs = NULL; > - g_autoptr(VhostIOVATree) iova_tree = NULL; > struct vhost_vdpa_iova_range iova_range; > NetClientState *nc; > int queue_pairs, r, i = 0, has_cvq = 0; > @@ -812,12 +872,8 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > goto err; > } > > - if (opts->x_svq) { > - if (!vhost_vdpa_net_valid_svq_features(features, errp)) { > - goto err_svq; > - } > - > - iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last); > + if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) { > + goto err; > } > > ncs = g_malloc0(sizeof(*ncs) * queue_pairs); > @@ -825,7 +881,7 @@ 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_range, iova_tree); > + iova_range); > if (!ncs[i]) > goto err; > } > @@ -833,13 +889,11 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > if (has_cvq) { > nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name, > vdpa_device_fd, i, 1, false, > - opts->x_svq, iova_range, iova_tree); > + opts->x_svq, iova_range); > if (!nc) > goto err; > } > > - /* iova_tree ownership belongs to last NetClientState */ > - g_steal_pointer(&iova_tree); > return 0; > > err: > @@ -849,7 +903,6 @@ err: > } > } > > -err_svq: > qemu_close(vdpa_device_fd); > > return -1;
On Mon, Feb 27, 2023 at 8:04 AM Jason Wang <jasowang@redhat.com> wrote: > > > 在 2023/2/24 23:54, Eugenio Pérez 写道: > > Only create iova_tree if and when it is needed. > > > > The cleanup keeps being responsible of last VQ but this change allows it > > to merge both cleanup functions. > > > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > > Acked-by: Jason Wang <jasowang@redhat.com> > > --- > > v4: > > * Remove leak of iova_tree because double allocation > > * Document better the sharing of IOVA tree between data and CVQ > > --- > > net/vhost-vdpa.c | 113 ++++++++++++++++++++++++++++++++++------------- > > 1 file changed, 83 insertions(+), 30 deletions(-) > > > > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c > > index de5ed8ff22..b89c99066a 100644 > > --- a/net/vhost-vdpa.c > > +++ b/net/vhost-vdpa.c > > @@ -178,13 +178,9 @@ err_init: > > static void vhost_vdpa_cleanup(NetClientState *nc) > > { > > VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > > - struct vhost_dev *dev = &s->vhost_net->dev; > > > > qemu_vfree(s->cvq_cmd_out_buffer); > > qemu_vfree(s->status); > > - if (dev->vq_index + dev->nvqs == dev->vq_index_end) { > > - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > > - } > > if (s->vhost_net) { > > vhost_net_cleanup(s->vhost_net); > > g_free(s->vhost_net); > > @@ -234,10 +230,64 @@ static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf, > > return size; > > } > > > > +/** From any vdpa net client, get the netclient of first queue pair */ > > +static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s) > > +{ > > + NICState *nic = qemu_get_nic(s->nc.peer); > > + NetClientState *nc0 = qemu_get_peer(nic->ncs, 0); > > + > > + return DO_UPCAST(VhostVDPAState, nc, nc0); > > +} > > + > > +static void vhost_vdpa_net_data_start_first(VhostVDPAState *s) > > +{ > > + struct vhost_vdpa *v = &s->vhost_vdpa; > > + > > + if (v->shadow_vqs_enabled) { > > + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > > + v->iova_range.last); > > + } > > +} > > + > > +static int vhost_vdpa_net_data_start(NetClientState *nc) > > +{ > > + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > > + struct vhost_vdpa *v = &s->vhost_vdpa; > > + > > + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); > > + > > + if (v->index == 0) { > > + vhost_vdpa_net_data_start_first(s); > > + return 0; > > + } > > + > > + if (v->shadow_vqs_enabled) { > > + VhostVDPAState *s0 = vhost_vdpa_net_first_nc_vdpa(s); > > + v->iova_tree = s0->vhost_vdpa.iova_tree; > > + } > > + > > + return 0; > > +} > > + > > +static void vhost_vdpa_net_client_stop(NetClientState *nc) > > +{ > > + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > > + struct vhost_dev *dev; > > + > > + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); > > + > > + dev = s->vhost_vdpa.dev; > > + if (dev->vq_index + dev->nvqs == dev->vq_index_end) { > > + g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > > + } > > +} > > + > > static NetClientInfo net_vhost_vdpa_info = { > > .type = NET_CLIENT_DRIVER_VHOST_VDPA, > > .size = sizeof(VhostVDPAState), > > .receive = vhost_vdpa_receive, > > + .start = vhost_vdpa_net_data_start, > > + .stop = vhost_vdpa_net_client_stop, > > > Looking at the implementation, it seems nothing net specific, any reason > we can't simply use vhost_vdpa_dev_start()? > IOVA tree must be shared between (at least) all dataplane vhost_vdpa. How could we move the call to vhost_vdpa_net_first_nc_vdpa to vhost_vdpa_dev_start? A possibility is to always allocate it just in case. But it seems to me it is better to not start allocating resources just in case :). > > > .cleanup = vhost_vdpa_cleanup, > > .has_vnet_hdr = vhost_vdpa_has_vnet_hdr, > > .has_ufo = vhost_vdpa_has_ufo, > > @@ -351,7 +401,7 @@ dma_map_err: > > > > static int vhost_vdpa_net_cvq_start(NetClientState *nc) > > { > > - VhostVDPAState *s; > > + VhostVDPAState *s, *s0; > > struct vhost_vdpa *v; > > uint64_t backend_features; > > int64_t cvq_group; > > @@ -415,8 +465,6 @@ static int vhost_vdpa_net_cvq_start(NetClientState *nc) > > return r; > > } > > > > - v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > > - v->iova_range.last); > > v->shadow_vqs_enabled = true; > > s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID; > > > > @@ -425,6 +473,27 @@ out: > > return 0; > > } > > > > + s0 = vhost_vdpa_net_first_nc_vdpa(s); > > + if (s0->vhost_vdpa.iova_tree) { > > + /* > > + * SVQ is already configured for all virtqueues. Reuse IOVA tree for > > + * simplicity, wether CVQ shares ASID with guest or not, because: > > > Typo, should be "whether", or "regardless of whether"(not a native speaker). > Good catch, I can fix it in the next version. Thanks! > Other looks good. > > Thanks > > > > + * - Memory listener need access to guest's memory addresses allocated > > + * in the IOVA tree. > > + * - There should be plenty of IOVA address space for both ASID not to > > + * worry about collisions between them. Guest's translations are > > + * still validated with virtio virtqueue_pop so there is no risk for > > + * the guest to access memory it shouldn't. > > + * > > + * To allocate a iova tree per ASID is doable but it complicates the > > + * code and it is not worth for the moment. > > + */ > > + v->iova_tree = s0->vhost_vdpa.iova_tree; > > + } else { > > + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > > + v->iova_range.last); > > + } > > + > > r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer, > > vhost_vdpa_net_cvq_cmd_page_len(), false); > > if (unlikely(r < 0)) { > > @@ -449,15 +518,9 @@ static void vhost_vdpa_net_cvq_stop(NetClientState *nc) > > if (s->vhost_vdpa.shadow_vqs_enabled) { > > vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer); > > vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status); > > - if (!s->always_svq) { > > - /* > > - * If only the CVQ is shadowed we can delete this safely. > > - * If all the VQs are shadows this will be needed by the time the > > - * device is started again to register SVQ vrings and similar. > > - */ > > - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > > - } > > } > > + > > + vhost_vdpa_net_client_stop(nc); > > } > > > > static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, size_t out_len, > > @@ -667,8 +730,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, > > int nvqs, > > bool is_datapath, > > bool svq, > > - struct vhost_vdpa_iova_range iova_range, > > - VhostIOVATree *iova_tree) > > + struct vhost_vdpa_iova_range iova_range) > > { > > NetClientState *nc = NULL; > > VhostVDPAState *s; > > @@ -690,7 +752,6 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, > > s->vhost_vdpa.shadow_vqs_enabled = svq; > > s->vhost_vdpa.iova_range = iova_range; > > s->vhost_vdpa.shadow_data = svq; > > - s->vhost_vdpa.iova_tree = iova_tree; > > if (!is_datapath) { > > s->cvq_cmd_out_buffer = qemu_memalign(qemu_real_host_page_size(), > > vhost_vdpa_net_cvq_cmd_page_len()); > > @@ -760,7 +821,6 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > > uint64_t features; > > int vdpa_device_fd; > > g_autofree NetClientState **ncs = NULL; > > - g_autoptr(VhostIOVATree) iova_tree = NULL; > > struct vhost_vdpa_iova_range iova_range; > > NetClientState *nc; > > int queue_pairs, r, i = 0, has_cvq = 0; > > @@ -812,12 +872,8 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > > goto err; > > } > > > > - if (opts->x_svq) { > > - if (!vhost_vdpa_net_valid_svq_features(features, errp)) { > > - goto err_svq; > > - } > > - > > - iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last); > > + if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) { > > + goto err; > > } > > > > ncs = g_malloc0(sizeof(*ncs) * queue_pairs); > > @@ -825,7 +881,7 @@ 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_range, iova_tree); > > + iova_range); > > if (!ncs[i]) > > goto err; > > } > > @@ -833,13 +889,11 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > > if (has_cvq) { > > nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name, > > vdpa_device_fd, i, 1, false, > > - opts->x_svq, iova_range, iova_tree); > > + opts->x_svq, iova_range); > > if (!nc) > > goto err; > > } > > > > - /* iova_tree ownership belongs to last NetClientState */ > > - g_steal_pointer(&iova_tree); > > return 0; > > > > err: > > @@ -849,7 +903,6 @@ err: > > } > > } > > > > -err_svq: > > qemu_close(vdpa_device_fd); > > > > return -1; >
在 2023/3/1 15:01, Eugenio Perez Martin 写道: > On Mon, Feb 27, 2023 at 8:04 AM Jason Wang <jasowang@redhat.com> wrote: >> >> 在 2023/2/24 23:54, Eugenio Pérez 写道: >>> Only create iova_tree if and when it is needed. >>> >>> The cleanup keeps being responsible of last VQ but this change allows it >>> to merge both cleanup functions. >>> >>> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> >>> Acked-by: Jason Wang <jasowang@redhat.com> >>> --- >>> v4: >>> * Remove leak of iova_tree because double allocation >>> * Document better the sharing of IOVA tree between data and CVQ >>> --- >>> net/vhost-vdpa.c | 113 ++++++++++++++++++++++++++++++++++------------- >>> 1 file changed, 83 insertions(+), 30 deletions(-) >>> >>> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c >>> index de5ed8ff22..b89c99066a 100644 >>> --- a/net/vhost-vdpa.c >>> +++ b/net/vhost-vdpa.c >>> @@ -178,13 +178,9 @@ err_init: >>> static void vhost_vdpa_cleanup(NetClientState *nc) >>> { >>> VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); >>> - struct vhost_dev *dev = &s->vhost_net->dev; >>> >>> qemu_vfree(s->cvq_cmd_out_buffer); >>> qemu_vfree(s->status); >>> - if (dev->vq_index + dev->nvqs == dev->vq_index_end) { >>> - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); >>> - } >>> if (s->vhost_net) { >>> vhost_net_cleanup(s->vhost_net); >>> g_free(s->vhost_net); >>> @@ -234,10 +230,64 @@ static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf, >>> return size; >>> } >>> >>> +/** From any vdpa net client, get the netclient of first queue pair */ >>> +static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s) >>> +{ >>> + NICState *nic = qemu_get_nic(s->nc.peer); >>> + NetClientState *nc0 = qemu_get_peer(nic->ncs, 0); >>> + >>> + return DO_UPCAST(VhostVDPAState, nc, nc0); >>> +} >>> + >>> +static void vhost_vdpa_net_data_start_first(VhostVDPAState *s) >>> +{ >>> + struct vhost_vdpa *v = &s->vhost_vdpa; >>> + >>> + if (v->shadow_vqs_enabled) { >>> + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, >>> + v->iova_range.last); >>> + } >>> +} >>> + >>> +static int vhost_vdpa_net_data_start(NetClientState *nc) >>> +{ >>> + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); >>> + struct vhost_vdpa *v = &s->vhost_vdpa; >>> + >>> + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); >>> + >>> + if (v->index == 0) { >>> + vhost_vdpa_net_data_start_first(s); >>> + return 0; >>> + } >>> + >>> + if (v->shadow_vqs_enabled) { >>> + VhostVDPAState *s0 = vhost_vdpa_net_first_nc_vdpa(s); >>> + v->iova_tree = s0->vhost_vdpa.iova_tree; >>> + } >>> + >>> + return 0; >>> +} >>> + >>> +static void vhost_vdpa_net_client_stop(NetClientState *nc) >>> +{ >>> + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); >>> + struct vhost_dev *dev; >>> + >>> + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); >>> + >>> + dev = s->vhost_vdpa.dev; >>> + if (dev->vq_index + dev->nvqs == dev->vq_index_end) { >>> + g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); >>> + } >>> +} >>> + >>> static NetClientInfo net_vhost_vdpa_info = { >>> .type = NET_CLIENT_DRIVER_VHOST_VDPA, >>> .size = sizeof(VhostVDPAState), >>> .receive = vhost_vdpa_receive, >>> + .start = vhost_vdpa_net_data_start, >>> + .stop = vhost_vdpa_net_client_stop, >> >> Looking at the implementation, it seems nothing net specific, any reason >> we can't simply use vhost_vdpa_dev_start()? >> > IOVA tree must be shared between (at least) all dataplane vhost_vdpa. > How could we move the call to vhost_vdpa_net_first_nc_vdpa to > vhost_vdpa_dev_start? Ok, I think I get it. We should really consider to implement a parent structure in the future for vhost_vdpa then we can avoid tricks like: vq_index_end and vhost_vdpa_net_first_nc_vdpa() Thanks > > A possibility is to always allocate it just in case. But it seems to > me it is better to not start allocating resources just in case :). > >>> .cleanup = vhost_vdpa_cleanup, >>> .has_vnet_hdr = vhost_vdpa_has_vnet_hdr, >>> .has_ufo = vhost_vdpa_has_ufo, >>> @@ -351,7 +401,7 @@ dma_map_err: >>> >>> static int vhost_vdpa_net_cvq_start(NetClientState *nc) >>> { >>> - VhostVDPAState *s; >>> + VhostVDPAState *s, *s0; >>> struct vhost_vdpa *v; >>> uint64_t backend_features; >>> int64_t cvq_group; >>> @@ -415,8 +465,6 @@ static int vhost_vdpa_net_cvq_start(NetClientState *nc) >>> return r; >>> } >>> >>> - v->iova_tree = vhost_iova_tree_new(v->iova_range.first, >>> - v->iova_range.last); >>> v->shadow_vqs_enabled = true; >>> s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID; >>> >>> @@ -425,6 +473,27 @@ out: >>> return 0; >>> } >>> >>> + s0 = vhost_vdpa_net_first_nc_vdpa(s); >>> + if (s0->vhost_vdpa.iova_tree) { >>> + /* >>> + * SVQ is already configured for all virtqueues. Reuse IOVA tree for >>> + * simplicity, wether CVQ shares ASID with guest or not, because: >> >> Typo, should be "whether", or "regardless of whether"(not a native speaker). >> > Good catch, I can fix it in the next version. > > Thanks! > >> Other looks good. >> >> Thanks >> >> >>> + * - Memory listener need access to guest's memory addresses allocated >>> + * in the IOVA tree. >>> + * - There should be plenty of IOVA address space for both ASID not to >>> + * worry about collisions between them. Guest's translations are >>> + * still validated with virtio virtqueue_pop so there is no risk for >>> + * the guest to access memory it shouldn't. >>> + * >>> + * To allocate a iova tree per ASID is doable but it complicates the >>> + * code and it is not worth for the moment. >>> + */ >>> + v->iova_tree = s0->vhost_vdpa.iova_tree; >>> + } else { >>> + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, >>> + v->iova_range.last); >>> + } >>> + >>> r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer, >>> vhost_vdpa_net_cvq_cmd_page_len(), false); >>> if (unlikely(r < 0)) { >>> @@ -449,15 +518,9 @@ static void vhost_vdpa_net_cvq_stop(NetClientState *nc) >>> if (s->vhost_vdpa.shadow_vqs_enabled) { >>> vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer); >>> vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status); >>> - if (!s->always_svq) { >>> - /* >>> - * If only the CVQ is shadowed we can delete this safely. >>> - * If all the VQs are shadows this will be needed by the time the >>> - * device is started again to register SVQ vrings and similar. >>> - */ >>> - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); >>> - } >>> } >>> + >>> + vhost_vdpa_net_client_stop(nc); >>> } >>> >>> static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, size_t out_len, >>> @@ -667,8 +730,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, >>> int nvqs, >>> bool is_datapath, >>> bool svq, >>> - struct vhost_vdpa_iova_range iova_range, >>> - VhostIOVATree *iova_tree) >>> + struct vhost_vdpa_iova_range iova_range) >>> { >>> NetClientState *nc = NULL; >>> VhostVDPAState *s; >>> @@ -690,7 +752,6 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, >>> s->vhost_vdpa.shadow_vqs_enabled = svq; >>> s->vhost_vdpa.iova_range = iova_range; >>> s->vhost_vdpa.shadow_data = svq; >>> - s->vhost_vdpa.iova_tree = iova_tree; >>> if (!is_datapath) { >>> s->cvq_cmd_out_buffer = qemu_memalign(qemu_real_host_page_size(), >>> vhost_vdpa_net_cvq_cmd_page_len()); >>> @@ -760,7 +821,6 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, >>> uint64_t features; >>> int vdpa_device_fd; >>> g_autofree NetClientState **ncs = NULL; >>> - g_autoptr(VhostIOVATree) iova_tree = NULL; >>> struct vhost_vdpa_iova_range iova_range; >>> NetClientState *nc; >>> int queue_pairs, r, i = 0, has_cvq = 0; >>> @@ -812,12 +872,8 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, >>> goto err; >>> } >>> >>> - if (opts->x_svq) { >>> - if (!vhost_vdpa_net_valid_svq_features(features, errp)) { >>> - goto err_svq; >>> - } >>> - >>> - iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last); >>> + if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) { >>> + goto err; >>> } >>> >>> ncs = g_malloc0(sizeof(*ncs) * queue_pairs); >>> @@ -825,7 +881,7 @@ 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_range, iova_tree); >>> + iova_range); >>> if (!ncs[i]) >>> goto err; >>> } >>> @@ -833,13 +889,11 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, >>> if (has_cvq) { >>> nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name, >>> vdpa_device_fd, i, 1, false, >>> - opts->x_svq, iova_range, iova_tree); >>> + opts->x_svq, iova_range); >>> if (!nc) >>> goto err; >>> } >>> >>> - /* iova_tree ownership belongs to last NetClientState */ >>> - g_steal_pointer(&iova_tree); >>> return 0; >>> >>> err: >>> @@ -849,7 +903,6 @@ err: >>> } >>> } >>> >>> -err_svq: >>> qemu_close(vdpa_device_fd); >>> >>> return -1;
On Fri, Mar 3, 2023 at 4:32 AM Jason Wang <jasowang@redhat.com> wrote: > > > 在 2023/3/1 15:01, Eugenio Perez Martin 写道: > > On Mon, Feb 27, 2023 at 8:04 AM Jason Wang <jasowang@redhat.com> wrote: > >> > >> 在 2023/2/24 23:54, Eugenio Pérez 写道: > >>> Only create iova_tree if and when it is needed. > >>> > >>> The cleanup keeps being responsible of last VQ but this change allows it > >>> to merge both cleanup functions. > >>> > >>> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > >>> Acked-by: Jason Wang <jasowang@redhat.com> > >>> --- > >>> v4: > >>> * Remove leak of iova_tree because double allocation > >>> * Document better the sharing of IOVA tree between data and CVQ > >>> --- > >>> net/vhost-vdpa.c | 113 ++++++++++++++++++++++++++++++++++------------- > >>> 1 file changed, 83 insertions(+), 30 deletions(-) > >>> > >>> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c > >>> index de5ed8ff22..b89c99066a 100644 > >>> --- a/net/vhost-vdpa.c > >>> +++ b/net/vhost-vdpa.c > >>> @@ -178,13 +178,9 @@ err_init: > >>> static void vhost_vdpa_cleanup(NetClientState *nc) > >>> { > >>> VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > >>> - struct vhost_dev *dev = &s->vhost_net->dev; > >>> > >>> qemu_vfree(s->cvq_cmd_out_buffer); > >>> qemu_vfree(s->status); > >>> - if (dev->vq_index + dev->nvqs == dev->vq_index_end) { > >>> - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > >>> - } > >>> if (s->vhost_net) { > >>> vhost_net_cleanup(s->vhost_net); > >>> g_free(s->vhost_net); > >>> @@ -234,10 +230,64 @@ static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf, > >>> return size; > >>> } > >>> > >>> +/** From any vdpa net client, get the netclient of first queue pair */ > >>> +static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s) > >>> +{ > >>> + NICState *nic = qemu_get_nic(s->nc.peer); > >>> + NetClientState *nc0 = qemu_get_peer(nic->ncs, 0); > >>> + > >>> + return DO_UPCAST(VhostVDPAState, nc, nc0); > >>> +} > >>> + > >>> +static void vhost_vdpa_net_data_start_first(VhostVDPAState *s) > >>> +{ > >>> + struct vhost_vdpa *v = &s->vhost_vdpa; > >>> + > >>> + if (v->shadow_vqs_enabled) { > >>> + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > >>> + v->iova_range.last); > >>> + } > >>> +} > >>> + > >>> +static int vhost_vdpa_net_data_start(NetClientState *nc) > >>> +{ > >>> + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > >>> + struct vhost_vdpa *v = &s->vhost_vdpa; > >>> + > >>> + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); > >>> + > >>> + if (v->index == 0) { > >>> + vhost_vdpa_net_data_start_first(s); > >>> + return 0; > >>> + } > >>> + > >>> + if (v->shadow_vqs_enabled) { > >>> + VhostVDPAState *s0 = vhost_vdpa_net_first_nc_vdpa(s); > >>> + v->iova_tree = s0->vhost_vdpa.iova_tree; > >>> + } > >>> + > >>> + return 0; > >>> +} > >>> + > >>> +static void vhost_vdpa_net_client_stop(NetClientState *nc) > >>> +{ > >>> + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > >>> + struct vhost_dev *dev; > >>> + > >>> + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); > >>> + > >>> + dev = s->vhost_vdpa.dev; > >>> + if (dev->vq_index + dev->nvqs == dev->vq_index_end) { > >>> + g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > >>> + } > >>> +} > >>> + > >>> static NetClientInfo net_vhost_vdpa_info = { > >>> .type = NET_CLIENT_DRIVER_VHOST_VDPA, > >>> .size = sizeof(VhostVDPAState), > >>> .receive = vhost_vdpa_receive, > >>> + .start = vhost_vdpa_net_data_start, > >>> + .stop = vhost_vdpa_net_client_stop, > >> > >> Looking at the implementation, it seems nothing net specific, any reason > >> we can't simply use vhost_vdpa_dev_start()? > >> > > IOVA tree must be shared between (at least) all dataplane vhost_vdpa. > > How could we move the call to vhost_vdpa_net_first_nc_vdpa to > > vhost_vdpa_dev_start? > > > Ok, I think I get it. We should really consider to implement a parent > structure in the future for vhost_vdpa then we can avoid tricks like: > > vq_index_end and vhost_vdpa_net_first_nc_vdpa() > Sounds right. Maybe it is enough to link all of them with a QLIST? Thanks! > Thanks > > > > > > A possibility is to always allocate it just in case. But it seems to > > me it is better to not start allocating resources just in case :). > > > >>> .cleanup = vhost_vdpa_cleanup, > >>> .has_vnet_hdr = vhost_vdpa_has_vnet_hdr, > >>> .has_ufo = vhost_vdpa_has_ufo, > >>> @@ -351,7 +401,7 @@ dma_map_err: > >>> > >>> static int vhost_vdpa_net_cvq_start(NetClientState *nc) > >>> { > >>> - VhostVDPAState *s; > >>> + VhostVDPAState *s, *s0; > >>> struct vhost_vdpa *v; > >>> uint64_t backend_features; > >>> int64_t cvq_group; > >>> @@ -415,8 +465,6 @@ static int vhost_vdpa_net_cvq_start(NetClientState *nc) > >>> return r; > >>> } > >>> > >>> - v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > >>> - v->iova_range.last); > >>> v->shadow_vqs_enabled = true; > >>> s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID; > >>> > >>> @@ -425,6 +473,27 @@ out: > >>> return 0; > >>> } > >>> > >>> + s0 = vhost_vdpa_net_first_nc_vdpa(s); > >>> + if (s0->vhost_vdpa.iova_tree) { > >>> + /* > >>> + * SVQ is already configured for all virtqueues. Reuse IOVA tree for > >>> + * simplicity, wether CVQ shares ASID with guest or not, because: > >> > >> Typo, should be "whether", or "regardless of whether"(not a native speaker). > >> > > Good catch, I can fix it in the next version. > > > > Thanks! > > > >> Other looks good. > >> > >> Thanks > >> > >> > >>> + * - Memory listener need access to guest's memory addresses allocated > >>> + * in the IOVA tree. > >>> + * - There should be plenty of IOVA address space for both ASID not to > >>> + * worry about collisions between them. Guest's translations are > >>> + * still validated with virtio virtqueue_pop so there is no risk for > >>> + * the guest to access memory it shouldn't. > >>> + * > >>> + * To allocate a iova tree per ASID is doable but it complicates the > >>> + * code and it is not worth for the moment. > >>> + */ > >>> + v->iova_tree = s0->vhost_vdpa.iova_tree; > >>> + } else { > >>> + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > >>> + v->iova_range.last); > >>> + } > >>> + > >>> r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer, > >>> vhost_vdpa_net_cvq_cmd_page_len(), false); > >>> if (unlikely(r < 0)) { > >>> @@ -449,15 +518,9 @@ static void vhost_vdpa_net_cvq_stop(NetClientState *nc) > >>> if (s->vhost_vdpa.shadow_vqs_enabled) { > >>> vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer); > >>> vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status); > >>> - if (!s->always_svq) { > >>> - /* > >>> - * If only the CVQ is shadowed we can delete this safely. > >>> - * If all the VQs are shadows this will be needed by the time the > >>> - * device is started again to register SVQ vrings and similar. > >>> - */ > >>> - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > >>> - } > >>> } > >>> + > >>> + vhost_vdpa_net_client_stop(nc); > >>> } > >>> > >>> static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, size_t out_len, > >>> @@ -667,8 +730,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, > >>> int nvqs, > >>> bool is_datapath, > >>> bool svq, > >>> - struct vhost_vdpa_iova_range iova_range, > >>> - VhostIOVATree *iova_tree) > >>> + struct vhost_vdpa_iova_range iova_range) > >>> { > >>> NetClientState *nc = NULL; > >>> VhostVDPAState *s; > >>> @@ -690,7 +752,6 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, > >>> s->vhost_vdpa.shadow_vqs_enabled = svq; > >>> s->vhost_vdpa.iova_range = iova_range; > >>> s->vhost_vdpa.shadow_data = svq; > >>> - s->vhost_vdpa.iova_tree = iova_tree; > >>> if (!is_datapath) { > >>> s->cvq_cmd_out_buffer = qemu_memalign(qemu_real_host_page_size(), > >>> vhost_vdpa_net_cvq_cmd_page_len()); > >>> @@ -760,7 +821,6 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > >>> uint64_t features; > >>> int vdpa_device_fd; > >>> g_autofree NetClientState **ncs = NULL; > >>> - g_autoptr(VhostIOVATree) iova_tree = NULL; > >>> struct vhost_vdpa_iova_range iova_range; > >>> NetClientState *nc; > >>> int queue_pairs, r, i = 0, has_cvq = 0; > >>> @@ -812,12 +872,8 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > >>> goto err; > >>> } > >>> > >>> - if (opts->x_svq) { > >>> - if (!vhost_vdpa_net_valid_svq_features(features, errp)) { > >>> - goto err_svq; > >>> - } > >>> - > >>> - iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last); > >>> + if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) { > >>> + goto err; > >>> } > >>> > >>> ncs = g_malloc0(sizeof(*ncs) * queue_pairs); > >>> @@ -825,7 +881,7 @@ 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_range, iova_tree); > >>> + iova_range); > >>> if (!ncs[i]) > >>> goto err; > >>> } > >>> @@ -833,13 +889,11 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > >>> if (has_cvq) { > >>> nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name, > >>> vdpa_device_fd, i, 1, false, > >>> - opts->x_svq, iova_range, iova_tree); > >>> + opts->x_svq, iova_range); > >>> if (!nc) > >>> goto err; > >>> } > >>> > >>> - /* iova_tree ownership belongs to last NetClientState */ > >>> - g_steal_pointer(&iova_tree); > >>> return 0; > >>> > >>> err: > >>> @@ -849,7 +903,6 @@ err: > >>> } > >>> } > >>> > >>> -err_svq: > >>> qemu_close(vdpa_device_fd); > >>> > >>> return -1; >
On Fri, Mar 3, 2023 at 4:01 PM Eugenio Perez Martin <eperezma@redhat.com> wrote: > > On Fri, Mar 3, 2023 at 4:32 AM Jason Wang <jasowang@redhat.com> wrote: > > > > > > 在 2023/3/1 15:01, Eugenio Perez Martin 写道: > > > On Mon, Feb 27, 2023 at 8:04 AM Jason Wang <jasowang@redhat.com> wrote: > > >> > > >> 在 2023/2/24 23:54, Eugenio Pérez 写道: > > >>> Only create iova_tree if and when it is needed. > > >>> > > >>> The cleanup keeps being responsible of last VQ but this change allows it > > >>> to merge both cleanup functions. > > >>> > > >>> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > > >>> Acked-by: Jason Wang <jasowang@redhat.com> > > >>> --- > > >>> v4: > > >>> * Remove leak of iova_tree because double allocation > > >>> * Document better the sharing of IOVA tree between data and CVQ > > >>> --- > > >>> net/vhost-vdpa.c | 113 ++++++++++++++++++++++++++++++++++------------- > > >>> 1 file changed, 83 insertions(+), 30 deletions(-) > > >>> > > >>> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c > > >>> index de5ed8ff22..b89c99066a 100644 > > >>> --- a/net/vhost-vdpa.c > > >>> +++ b/net/vhost-vdpa.c > > >>> @@ -178,13 +178,9 @@ err_init: > > >>> static void vhost_vdpa_cleanup(NetClientState *nc) > > >>> { > > >>> VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > > >>> - struct vhost_dev *dev = &s->vhost_net->dev; > > >>> > > >>> qemu_vfree(s->cvq_cmd_out_buffer); > > >>> qemu_vfree(s->status); > > >>> - if (dev->vq_index + dev->nvqs == dev->vq_index_end) { > > >>> - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > > >>> - } > > >>> if (s->vhost_net) { > > >>> vhost_net_cleanup(s->vhost_net); > > >>> g_free(s->vhost_net); > > >>> @@ -234,10 +230,64 @@ static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf, > > >>> return size; > > >>> } > > >>> > > >>> +/** From any vdpa net client, get the netclient of first queue pair */ > > >>> +static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s) > > >>> +{ > > >>> + NICState *nic = qemu_get_nic(s->nc.peer); > > >>> + NetClientState *nc0 = qemu_get_peer(nic->ncs, 0); > > >>> + > > >>> + return DO_UPCAST(VhostVDPAState, nc, nc0); > > >>> +} > > >>> + > > >>> +static void vhost_vdpa_net_data_start_first(VhostVDPAState *s) > > >>> +{ > > >>> + struct vhost_vdpa *v = &s->vhost_vdpa; > > >>> + > > >>> + if (v->shadow_vqs_enabled) { > > >>> + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > > >>> + v->iova_range.last); > > >>> + } > > >>> +} > > >>> + > > >>> +static int vhost_vdpa_net_data_start(NetClientState *nc) > > >>> +{ > > >>> + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > > >>> + struct vhost_vdpa *v = &s->vhost_vdpa; > > >>> + > > >>> + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); > > >>> + > > >>> + if (v->index == 0) { > > >>> + vhost_vdpa_net_data_start_first(s); > > >>> + return 0; > > >>> + } > > >>> + > > >>> + if (v->shadow_vqs_enabled) { > > >>> + VhostVDPAState *s0 = vhost_vdpa_net_first_nc_vdpa(s); > > >>> + v->iova_tree = s0->vhost_vdpa.iova_tree; > > >>> + } > > >>> + > > >>> + return 0; > > >>> +} > > >>> + > > >>> +static void vhost_vdpa_net_client_stop(NetClientState *nc) > > >>> +{ > > >>> + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); > > >>> + struct vhost_dev *dev; > > >>> + > > >>> + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); > > >>> + > > >>> + dev = s->vhost_vdpa.dev; > > >>> + if (dev->vq_index + dev->nvqs == dev->vq_index_end) { > > >>> + g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > > >>> + } > > >>> +} > > >>> + > > >>> static NetClientInfo net_vhost_vdpa_info = { > > >>> .type = NET_CLIENT_DRIVER_VHOST_VDPA, > > >>> .size = sizeof(VhostVDPAState), > > >>> .receive = vhost_vdpa_receive, > > >>> + .start = vhost_vdpa_net_data_start, > > >>> + .stop = vhost_vdpa_net_client_stop, > > >> > > >> Looking at the implementation, it seems nothing net specific, any reason > > >> we can't simply use vhost_vdpa_dev_start()? > > >> > > > IOVA tree must be shared between (at least) all dataplane vhost_vdpa. > > > How could we move the call to vhost_vdpa_net_first_nc_vdpa to > > > vhost_vdpa_dev_start? > > > > > > Ok, I think I get it. We should really consider to implement a parent > > structure in the future for vhost_vdpa then we can avoid tricks like: > > > > vq_index_end and vhost_vdpa_net_first_nc_vdpa() > > > > Sounds right. Maybe it is enough to link all of them with a QLIST? That's also fine but you need to place the parent data into the head structure which seems not clean than having pointers to point to the same parent structure. Thanks > > Thanks! > > > Thanks > > > > > > > > > > A possibility is to always allocate it just in case. But it seems to > > > me it is better to not start allocating resources just in case :). > > > > > >>> .cleanup = vhost_vdpa_cleanup, > > >>> .has_vnet_hdr = vhost_vdpa_has_vnet_hdr, > > >>> .has_ufo = vhost_vdpa_has_ufo, > > >>> @@ -351,7 +401,7 @@ dma_map_err: > > >>> > > >>> static int vhost_vdpa_net_cvq_start(NetClientState *nc) > > >>> { > > >>> - VhostVDPAState *s; > > >>> + VhostVDPAState *s, *s0; > > >>> struct vhost_vdpa *v; > > >>> uint64_t backend_features; > > >>> int64_t cvq_group; > > >>> @@ -415,8 +465,6 @@ static int vhost_vdpa_net_cvq_start(NetClientState *nc) > > >>> return r; > > >>> } > > >>> > > >>> - v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > > >>> - v->iova_range.last); > > >>> v->shadow_vqs_enabled = true; > > >>> s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID; > > >>> > > >>> @@ -425,6 +473,27 @@ out: > > >>> return 0; > > >>> } > > >>> > > >>> + s0 = vhost_vdpa_net_first_nc_vdpa(s); > > >>> + if (s0->vhost_vdpa.iova_tree) { > > >>> + /* > > >>> + * SVQ is already configured for all virtqueues. Reuse IOVA tree for > > >>> + * simplicity, wether CVQ shares ASID with guest or not, because: > > >> > > >> Typo, should be "whether", or "regardless of whether"(not a native speaker). > > >> > > > Good catch, I can fix it in the next version. > > > > > > Thanks! > > > > > >> Other looks good. > > >> > > >> Thanks > > >> > > >> > > >>> + * - Memory listener need access to guest's memory addresses allocated > > >>> + * in the IOVA tree. > > >>> + * - There should be plenty of IOVA address space for both ASID not to > > >>> + * worry about collisions between them. Guest's translations are > > >>> + * still validated with virtio virtqueue_pop so there is no risk for > > >>> + * the guest to access memory it shouldn't. > > >>> + * > > >>> + * To allocate a iova tree per ASID is doable but it complicates the > > >>> + * code and it is not worth for the moment. > > >>> + */ > > >>> + v->iova_tree = s0->vhost_vdpa.iova_tree; > > >>> + } else { > > >>> + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, > > >>> + v->iova_range.last); > > >>> + } > > >>> + > > >>> r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer, > > >>> vhost_vdpa_net_cvq_cmd_page_len(), false); > > >>> if (unlikely(r < 0)) { > > >>> @@ -449,15 +518,9 @@ static void vhost_vdpa_net_cvq_stop(NetClientState *nc) > > >>> if (s->vhost_vdpa.shadow_vqs_enabled) { > > >>> vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer); > > >>> vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status); > > >>> - if (!s->always_svq) { > > >>> - /* > > >>> - * If only the CVQ is shadowed we can delete this safely. > > >>> - * If all the VQs are shadows this will be needed by the time the > > >>> - * device is started again to register SVQ vrings and similar. > > >>> - */ > > >>> - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); > > >>> - } > > >>> } > > >>> + > > >>> + vhost_vdpa_net_client_stop(nc); > > >>> } > > >>> > > >>> static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, size_t out_len, > > >>> @@ -667,8 +730,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, > > >>> int nvqs, > > >>> bool is_datapath, > > >>> bool svq, > > >>> - struct vhost_vdpa_iova_range iova_range, > > >>> - VhostIOVATree *iova_tree) > > >>> + struct vhost_vdpa_iova_range iova_range) > > >>> { > > >>> NetClientState *nc = NULL; > > >>> VhostVDPAState *s; > > >>> @@ -690,7 +752,6 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, > > >>> s->vhost_vdpa.shadow_vqs_enabled = svq; > > >>> s->vhost_vdpa.iova_range = iova_range; > > >>> s->vhost_vdpa.shadow_data = svq; > > >>> - s->vhost_vdpa.iova_tree = iova_tree; > > >>> if (!is_datapath) { > > >>> s->cvq_cmd_out_buffer = qemu_memalign(qemu_real_host_page_size(), > > >>> vhost_vdpa_net_cvq_cmd_page_len()); > > >>> @@ -760,7 +821,6 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > > >>> uint64_t features; > > >>> int vdpa_device_fd; > > >>> g_autofree NetClientState **ncs = NULL; > > >>> - g_autoptr(VhostIOVATree) iova_tree = NULL; > > >>> struct vhost_vdpa_iova_range iova_range; > > >>> NetClientState *nc; > > >>> int queue_pairs, r, i = 0, has_cvq = 0; > > >>> @@ -812,12 +872,8 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > > >>> goto err; > > >>> } > > >>> > > >>> - if (opts->x_svq) { > > >>> - if (!vhost_vdpa_net_valid_svq_features(features, errp)) { > > >>> - goto err_svq; > > >>> - } > > >>> - > > >>> - iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last); > > >>> + if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) { > > >>> + goto err; > > >>> } > > >>> > > >>> ncs = g_malloc0(sizeof(*ncs) * queue_pairs); > > >>> @@ -825,7 +881,7 @@ 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_range, iova_tree); > > >>> + iova_range); > > >>> if (!ncs[i]) > > >>> goto err; > > >>> } > > >>> @@ -833,13 +889,11 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, > > >>> if (has_cvq) { > > >>> nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name, > > >>> vdpa_device_fd, i, 1, false, > > >>> - opts->x_svq, iova_range, iova_tree); > > >>> + opts->x_svq, iova_range); > > >>> if (!nc) > > >>> goto err; > > >>> } > > >>> > > >>> - /* iova_tree ownership belongs to last NetClientState */ > > >>> - g_steal_pointer(&iova_tree); > > >>> return 0; > > >>> > > >>> err: > > >>> @@ -849,7 +903,6 @@ err: > > >>> } > > >>> } > > >>> > > >>> -err_svq: > > >>> qemu_close(vdpa_device_fd); > > >>> > > >>> return -1; > > >
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c index de5ed8ff22..b89c99066a 100644 --- a/net/vhost-vdpa.c +++ b/net/vhost-vdpa.c @@ -178,13 +178,9 @@ err_init: static void vhost_vdpa_cleanup(NetClientState *nc) { VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); - struct vhost_dev *dev = &s->vhost_net->dev; qemu_vfree(s->cvq_cmd_out_buffer); qemu_vfree(s->status); - if (dev->vq_index + dev->nvqs == dev->vq_index_end) { - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); - } if (s->vhost_net) { vhost_net_cleanup(s->vhost_net); g_free(s->vhost_net); @@ -234,10 +230,64 @@ static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf, return size; } +/** From any vdpa net client, get the netclient of first queue pair */ +static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s) +{ + NICState *nic = qemu_get_nic(s->nc.peer); + NetClientState *nc0 = qemu_get_peer(nic->ncs, 0); + + return DO_UPCAST(VhostVDPAState, nc, nc0); +} + +static void vhost_vdpa_net_data_start_first(VhostVDPAState *s) +{ + struct vhost_vdpa *v = &s->vhost_vdpa; + + if (v->shadow_vqs_enabled) { + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, + v->iova_range.last); + } +} + +static int vhost_vdpa_net_data_start(NetClientState *nc) +{ + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); + struct vhost_vdpa *v = &s->vhost_vdpa; + + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); + + if (v->index == 0) { + vhost_vdpa_net_data_start_first(s); + return 0; + } + + if (v->shadow_vqs_enabled) { + VhostVDPAState *s0 = vhost_vdpa_net_first_nc_vdpa(s); + v->iova_tree = s0->vhost_vdpa.iova_tree; + } + + return 0; +} + +static void vhost_vdpa_net_client_stop(NetClientState *nc) +{ + VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc); + struct vhost_dev *dev; + + assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA); + + dev = s->vhost_vdpa.dev; + if (dev->vq_index + dev->nvqs == dev->vq_index_end) { + g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); + } +} + static NetClientInfo net_vhost_vdpa_info = { .type = NET_CLIENT_DRIVER_VHOST_VDPA, .size = sizeof(VhostVDPAState), .receive = vhost_vdpa_receive, + .start = vhost_vdpa_net_data_start, + .stop = vhost_vdpa_net_client_stop, .cleanup = vhost_vdpa_cleanup, .has_vnet_hdr = vhost_vdpa_has_vnet_hdr, .has_ufo = vhost_vdpa_has_ufo, @@ -351,7 +401,7 @@ dma_map_err: static int vhost_vdpa_net_cvq_start(NetClientState *nc) { - VhostVDPAState *s; + VhostVDPAState *s, *s0; struct vhost_vdpa *v; uint64_t backend_features; int64_t cvq_group; @@ -415,8 +465,6 @@ static int vhost_vdpa_net_cvq_start(NetClientState *nc) return r; } - v->iova_tree = vhost_iova_tree_new(v->iova_range.first, - v->iova_range.last); v->shadow_vqs_enabled = true; s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID; @@ -425,6 +473,27 @@ out: return 0; } + s0 = vhost_vdpa_net_first_nc_vdpa(s); + if (s0->vhost_vdpa.iova_tree) { + /* + * SVQ is already configured for all virtqueues. Reuse IOVA tree for + * simplicity, wether CVQ shares ASID with guest or not, because: + * - Memory listener need access to guest's memory addresses allocated + * in the IOVA tree. + * - There should be plenty of IOVA address space for both ASID not to + * worry about collisions between them. Guest's translations are + * still validated with virtio virtqueue_pop so there is no risk for + * the guest to access memory it shouldn't. + * + * To allocate a iova tree per ASID is doable but it complicates the + * code and it is not worth for the moment. + */ + v->iova_tree = s0->vhost_vdpa.iova_tree; + } else { + v->iova_tree = vhost_iova_tree_new(v->iova_range.first, + v->iova_range.last); + } + r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer, vhost_vdpa_net_cvq_cmd_page_len(), false); if (unlikely(r < 0)) { @@ -449,15 +518,9 @@ static void vhost_vdpa_net_cvq_stop(NetClientState *nc) if (s->vhost_vdpa.shadow_vqs_enabled) { vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer); vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status); - if (!s->always_svq) { - /* - * If only the CVQ is shadowed we can delete this safely. - * If all the VQs are shadows this will be needed by the time the - * device is started again to register SVQ vrings and similar. - */ - g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete); - } } + + vhost_vdpa_net_client_stop(nc); } static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, size_t out_len, @@ -667,8 +730,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, int nvqs, bool is_datapath, bool svq, - struct vhost_vdpa_iova_range iova_range, - VhostIOVATree *iova_tree) + struct vhost_vdpa_iova_range iova_range) { NetClientState *nc = NULL; VhostVDPAState *s; @@ -690,7 +752,6 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer, s->vhost_vdpa.shadow_vqs_enabled = svq; s->vhost_vdpa.iova_range = iova_range; s->vhost_vdpa.shadow_data = svq; - s->vhost_vdpa.iova_tree = iova_tree; if (!is_datapath) { s->cvq_cmd_out_buffer = qemu_memalign(qemu_real_host_page_size(), vhost_vdpa_net_cvq_cmd_page_len()); @@ -760,7 +821,6 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, uint64_t features; int vdpa_device_fd; g_autofree NetClientState **ncs = NULL; - g_autoptr(VhostIOVATree) iova_tree = NULL; struct vhost_vdpa_iova_range iova_range; NetClientState *nc; int queue_pairs, r, i = 0, has_cvq = 0; @@ -812,12 +872,8 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, goto err; } - if (opts->x_svq) { - if (!vhost_vdpa_net_valid_svq_features(features, errp)) { - goto err_svq; - } - - iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last); + if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) { + goto err; } ncs = g_malloc0(sizeof(*ncs) * queue_pairs); @@ -825,7 +881,7 @@ 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_range, iova_tree); + iova_range); if (!ncs[i]) goto err; } @@ -833,13 +889,11 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, if (has_cvq) { nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name, vdpa_device_fd, i, 1, false, - opts->x_svq, iova_range, iova_tree); + opts->x_svq, iova_range); if (!nc) goto err; } - /* iova_tree ownership belongs to last NetClientState */ - g_steal_pointer(&iova_tree); return 0; err: @@ -849,7 +903,6 @@ err: } } -err_svq: qemu_close(vdpa_device_fd); return -1;