net: devmem: TCP tx netlink api

Add bind-tx netlink call to attach dmabuf for TX; queue is not
required, only ifindex and dmabuf fd for attachment.

Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20250508004830.4100853-4-almasrymina@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index f5e0750ab71db05d7729e9b93cf51df73391dfd8..c0ef6d0d77865ed3c11eb4156a2571acdbd937c8 100644 (file)
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -743,6 +743,18 @@ operations:
             - defer-hard-irqs
             - gro-flush-timeout
             - irq-suspend-timeout
+    -
+      name: bind-tx
+      doc: Bind dmabuf to netdev for TX
+      attribute-set: dmabuf
+      do:
+        request:
+          attributes:
+            - ifindex
+            - fd
+        reply:
+          attributes:
+            - id
 
 kernel-family:
   headers: [ "net/netdev_netlink.h"]

diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index 7600bf62dbdf07968db2ae143e3de99dff8b95bb..7eb9571786b83ed0b1e33bebff8a96cf60afd60b 100644 (file)
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -219,6 +219,7 @@ enum {
        NETDEV_CMD_QSTATS_GET,
        NETDEV_CMD_BIND_RX,
        NETDEV_CMD_NAPI_SET,
+       NETDEV_CMD_BIND_TX,
 
        __NETDEV_CMD_MAX,
        NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)

diff --git a/net/core/netdev-genl-gen.c b/net/core/netdev-genl-gen.c
index 739f7b6506a6a427e555e2b998133763b35c3547..4fc44587f4936c64ff41ee95f42d3e49a1159807 100644 (file)
--- a/net/core/netdev-genl-gen.c
+++ b/net/core/netdev-genl-gen.c
@@ -99,6 +99,12 @@ static const struct nla_policy netdev_napi_set_nl_policy[NETDEV_A_NAPI_IRQ_SUSPE
        [NETDEV_A_NAPI_IRQ_SUSPEND_TIMEOUT] = { .type = NLA_UINT, },
 };
 
+/* NETDEV_CMD_BIND_TX - do */
+static const struct nla_policy netdev_bind_tx_nl_policy[NETDEV_A_DMABUF_FD + 1] = {
+       [NETDEV_A_DMABUF_IFINDEX] = NLA_POLICY_MIN(NLA_U32, 1),
+       [NETDEV_A_DMABUF_FD] = { .type = NLA_U32, },
+};
+
 /* Ops table for netdev */
 static const struct genl_split_ops netdev_nl_ops[] = {
        {
@@ -190,6 +196,13 @@ static const struct genl_split_ops netdev_nl_ops[] = {
                .maxattr        = NETDEV_A_NAPI_IRQ_SUSPEND_TIMEOUT,
                .flags          = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
        },
+       {
+               .cmd            = NETDEV_CMD_BIND_TX,
+               .doit           = netdev_nl_bind_tx_doit,
+               .policy         = netdev_bind_tx_nl_policy,
+               .maxattr        = NETDEV_A_DMABUF_FD,
+               .flags          = GENL_CMD_CAP_DO,
+       },
 };
 
 static const struct genl_multicast_group netdev_nl_mcgrps[] = {

diff --git a/net/core/netdev-genl-gen.h b/net/core/netdev-genl-gen.h
index 17d39fd64c94851ffa3eb580e9f5750021eac4eb..cf3fad74511f5b623af171b7819f633fb4890035 100644 (file)
--- a/net/core/netdev-genl-gen.h
+++ b/net/core/netdev-genl-gen.h
@@ -34,6 +34,7 @@ int netdev_nl_qstats_get_dumpit(struct sk_buff *skb,
                                struct netlink_callback *cb);
 int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info);
 int netdev_nl_napi_set_doit(struct sk_buff *skb, struct genl_info *info);
+int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info);
 
 enum {
        NETDEV_NLGRP_MGMT,

diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 17aa9e42e8d5b86f51051a20472e4b577073b966..3beef87235d8a6388984c9f83ebf85c76531283f 100644 (file)
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -968,6 +968,12 @@ err_genlmsg_free:
        return err;
 }
 
+/* stub */
+int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info)
+{
+       return 0;
+}
+
 void netdev_nl_sock_priv_init(struct netdev_nl_sock *priv)
 {
        INIT_LIST_HEAD(&priv->bindings);

diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index 7600bf62dbdf07968db2ae143e3de99dff8b95bb..7eb9571786b83ed0b1e33bebff8a96cf60afd60b 100644 (file)
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -219,6 +219,7 @@ enum {
        NETDEV_CMD_QSTATS_GET,
        NETDEV_CMD_BIND_RX,
        NETDEV_CMD_NAPI_SET,
+       NETDEV_CMD_BIND_TX,
 
        __NETDEV_CMD_MAX,
        NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)