On Mon, 5 Aug 2024 21:25:16 +0000 Mina Almasry wrote:
+/* Protected by rtnl_lock() */
+static DEFINE_XARRAY_FLAGS(net_devmem_dmabuf_bindings, XA_FLAGS_ALLOC1);
nit: global variable declarations before any code
quoted hunk ↗ jump to hunk
+void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding)
+{
+ struct netdev_rx_queue *rxq;
+ unsigned long xa_idx;
+ unsigned int rxq_idx;
+
+ if (binding->list.next)
+ list_del(&binding->list);
+
+ xa_for_each(&binding->bound_rxqs, xa_idx, rxq) {
+ if (rxq->mp_params.mp_priv == binding) {
+ rxq->mp_params.mp_priv = NULL;
+
+ rxq_idx = get_netdev_rx_queue_index(rxq);
+
+ netdev_rx_queue_restart(binding->dev, rxq_idx);
Throw in a WARN_ON() around this, hopefully we'll get to addressing it
later..
quoted hunk ↗ jump to hunk
+ }
+ }
+
+ xa_erase(&net_devmem_dmabuf_bindings, binding->id);
+
+ net_devmem_dmabuf_binding_put(binding);
+}
+
+int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
+ struct net_devmem_dmabuf_binding *binding)
+{
+ struct netdev_rx_queue *rxq;
+ u32 xa_idx;
+ int err;
+
+ if (rxq_idx >= dev->real_num_rx_queues)
+ return -ERANGE;
If we prevent binding to an inactive queue we should also prevent
deactivation.
Please take a look at the (two?) callers of
ethtool_get_max_rxnfc_channel() and ethtool_get_max_rxfh_channel().
Wrap those into a new function for reading max active channel, and
take mp binds into account as well (send the refactor separately
from the series to avoid making it longer).
quoted hunk ↗ jump to hunk
+ rxq = __netif_get_rx_queue(dev, rxq_idx);
+ if (rxq->mp_params.mp_priv)
+ return -EEXIST;
+
+ err = xa_alloc(&binding->bound_rxqs, &xa_idx, rxq, xa_limit_32b,
+ GFP_KERNEL);
+ if (err)
+ return err;
+
+ rxq->mp_params.mp_priv = binding;
+
+ err = netdev_rx_queue_restart(dev, rxq_idx);
+ if (err)
+ goto err_xa_erase;
+
+ return 0;
+
+err_xa_erase:
+ rxq->mp_params.mp_priv = NULL;
+ xa_erase(&binding->bound_rxqs, xa_idx);
+
+ return err;
+}
quoted hunk ↗ jump to hunk
+void dev_dmabuf_uninstall(struct net_device *dev)
+{
+ unsigned int i, count = dev->num_rx_queues;
nit: why stash the value of num_rx_queues ?
quoted hunk ↗ jump to hunk
+ struct net_devmem_dmabuf_binding *binding;
+ struct netdev_rx_queue *rxq;
+ unsigned long xa_idx;
+
+ for (i = 0; i < count; i++) {
+ binding = dev->_rx[i].mp_params.mp_priv;
+ if (binding)
+ xa_for_each(&binding->bound_rxqs, xa_idx, rxq)
+ if (rxq == &dev->_rx[i])
+ xa_erase(&binding->bound_rxqs, xa_idx);
nit: Please use "continue", this is too deeply indented
quoted hunk ↗ jump to hunk
+ nla_for_each_attr_type(attr, NETDEV_A_DMABUF_QUEUES,
+ genlmsg_data(info->genlhdr),
+ genlmsg_len(info->genlhdr), rem) {
+ err = nla_parse_nested(
+ tb, ARRAY_SIZE(netdev_queue_id_nl_policy) - 1, attr,
+ netdev_queue_id_nl_policy, info->extack);
+ if (err < 0)
+ goto err_unbind;
+
+ rxq_idx = nla_get_u32(tb[NETDEV_A_QUEUE_ID]);
How do we know this attribute is present? NL_REQ_ATTR_CHECK()
quoted hunk ↗ jump to hunk
+ err = net_devmem_bind_dmabuf_to_queue(netdev, rxq_idx, binding);
+ if (err)
+ goto err_unbind;
+ }
+
+ list_add(&binding->list, sock_binding_list);
+
+ nla_put_u32(rsp, NETDEV_A_DMABUF_ID, binding->id);
+ genlmsg_end(rsp, hdr);
+
+ rtnl_unlock();
nit: for symmetry you should also unlock after list_add(),
netlink msg alloc and prep are before rtnl_lock()
quoted hunk ↗ jump to hunk
+ return genlmsg_reply(rsp, info);
+
+err_unbind:
+ net_devmem_unbind_dmabuf(binding);
+err_unlock:
+ rtnl_unlock();
+err_genlmsg_free:
+ nlmsg_free(rsp);
+ return err;
}
quoted hunk ↗ jump to hunk
+void netdev_nl_sock_priv_init(struct list_head *priv)
+{
+ INIT_LIST_HEAD(priv);
+}
+
+void netdev_nl_sock_priv_destroy(struct list_head *priv)
+{
+ struct net_devmem_dmabuf_binding *binding;
+ struct net_devmem_dmabuf_binding *temp;
+
+ list_for_each_entry_safe(binding, temp, priv, list) {
+ rtnl_lock();
+ net_devmem_unbind_dmabuf(binding);
+ rtnl_unlock();
+ }
+}
nit: move these before the subsys_initcall.. and what it calls