[PATCH net-next v1 1/4] net: create netdev_nl_sock to wrap bindings list

Stanislav Fomichev
2025-03-07T15:57:28Z

No functional changes. Next patches will add more granular locking
to netdev_nl_sock.

Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
---
Documentation/netlink/specs/netdev.yaml | 4 ++--
include/net/netdev_netlink.h | 11 +++++++++++
net/core/netdev-genl-gen.c | 4 ++--
net/core/netdev-genl-gen.h | 6 +++---
net/core/netdev-genl.c | 19 +++++++++----------
5 files changed, 27 insertions(+), 17 deletions(-)
create mode 100644 include/net/netdev_netlink.h

diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index 36f1152bfac3..f5e0750ab71d 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -745,8 +745,8 @@ name: netdev
- irq-suspend-timeout

kernel-family:
- headers: [ "linux/list.h"]
- sock-priv: struct list_head
+ headers: [ "net/netdev_netlink.h"]
+ sock-priv: struct netdev_nl_sock

mcast-groups:
list:
diff --git a/include/net/netdev_netlink.h b/include/net/netdev_netlink.h
new file mode 100644
index 000000000000..1599573d35c9
--- /dev/null
+++ b/include/net/netdev_netlink.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NET_NETDEV_NETLINK_H
+#define __NET_NETDEV_NETLINK_H
+
+#include <linux/list.h>
+
+struct netdev_nl_sock {
+ struct list_head bindings;
+};
+
+#endif /* __NET_NETDEV_NETLINK_H */
diff --git a/net/core/netdev-genl-gen.c b/net/core/netdev-genl-gen.c
index 996ac6a449eb..739f7b6506a6 100644
--- a/net/core/netdev-genl-gen.c
+++ b/net/core/netdev-genl-gen.c
@@ -9,7 +9,7 @@
#include "netdev-genl-gen.h"

#include <uapi/linux/netdev.h>
-#include <linux/list.h>
+#include <net/netdev_netlink.h>

/* Integer value ranges */
static const struct netlink_range_validation netdev_a_page_pool_id_range = {
@@ -217,7 +217,7 @@ struct genl_family netdev_nl_family __ro_after_init = {
.n_split_ops = ARRAY_SIZE(netdev_nl_ops),
.mcgrps = netdev_nl_mcgrps,
.n_mcgrps = ARRAY_SIZE(netdev_nl_mcgrps),
- .sock_priv_size = sizeof(struct list_head),
+ .sock_priv_size = sizeof(struct netdev_nl_sock),
.sock_priv_init = __netdev_nl_sock_priv_init,
.sock_priv_destroy = __netdev_nl_sock_priv_destroy,
};
diff --git a/net/core/netdev-genl-gen.h b/net/core/netdev-genl-gen.h
index e09dd7539ff2..17d39fd64c94 100644
--- a/net/core/netdev-genl-gen.h
+++ b/net/core/netdev-genl-gen.h
@@ -10,7 +10,7 @@
#include <net/genetlink.h>

#include <uapi/linux/netdev.h>
-#include <linux/list.h>
+#include <net/netdev_netlink.h>

/* Common nested types */
extern const struct nla_policy netdev_page_pool_info_nl_policy[NETDEV_A_PAGE_POOL_IFINDEX + 1];
@@ -42,7 +42,7 @@ enum {

extern struct genl_family netdev_nl_family;

-void netdev_nl_sock_priv_init(struct list_head *priv);
-void netdev_nl_sock_priv_destroy(struct list_head *priv);
+void netdev_nl_sock_priv_init(struct netdev_nl_sock *priv);
+void netdev_nl_sock_priv_destroy(struct netdev_nl_sock *priv);

#endif /* _LINUX_NETDEV_GEN_H */
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 2b774183d31c..a219be90c739 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -829,8 +829,8 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *tb[ARRAY_SIZE(netdev_queue_id_nl_policy)];
struct net_devmem_dmabuf_binding *binding;
- struct list_head *sock_binding_list;
u32 ifindex, dmabuf_fd, rxq_idx;
+ struct netdev_nl_sock *priv;
struct net_device *netdev;
struct sk_buff *rsp;
struct nlattr *attr;
@@ -845,10 +845,9 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info)
ifindex = nla_get_u32(info->attrs[NETDEV_A_DEV_IFINDEX]);
dmabuf_fd = nla_get_u32(info->attrs[NETDEV_A_DMABUF_FD]);

- sock_binding_list = genl_sk_priv_get(&netdev_nl_family,
- NETLINK_CB(skb).sk);
- if (IS_ERR(sock_binding_list))
- return PTR_ERR(sock_binding_list);
+ priv = genl_sk_priv_get(&netdev_nl_family, NETLINK_CB(skb).sk);
+ if (IS_ERR(priv))
+ return PTR_ERR(priv);

rsp = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (!rsp)
@@ -909,7 +908,7 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info)
goto err_unbind;
}

- list_add(&binding->list, sock_binding_list);
+ list_add(&binding->list, &priv->bindings);

nla_put_u32(rsp, NETDEV_A_DMABUF_ID, binding->id);
genlmsg_end(rsp, hdr);
@@ -931,17 +930,17 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info)
return err;
}

-void netdev_nl_sock_priv_init(struct list_head *priv)
+void netdev_nl_sock_priv_init(struct netdev_nl_sock *priv)
{
- INIT_LIST_HEAD(priv);
+ INIT_LIST_HEAD(&priv->bindings);
}

-void netdev_nl_sock_priv_destroy(struct list_head *priv)
+void netdev_nl_sock_priv_destroy(struct netdev_nl_sock *priv)
{
struct net_devmem_dmabuf_binding *binding;
struct net_devmem_dmabuf_binding *temp;

- list_for_each_entry_safe(binding, temp, priv, list) {
+ list_for_each_entry_safe(binding, temp, &priv->bindings, list) {
rtnl_lock();
net_devmem_unbind_dmabuf(binding);
rtnl_unlock();
--
2.48.1