[PATCH net-next v8 3/9] net: devmem: TCP tx netlink api

[Mina Almasry <almasrymina@google.com>]

From: Stanislav Fomichev <sdf@fomichev.me>

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>

---

v3:
- Fix ynl-regen.sh error (Simon).

---
 Documentation/netlink/specs/netdev.yaml | 12 ++++++++++++
 include/uapi/linux/netdev.h             |  1 +
 net/core/netdev-genl-gen.c              | 13 +++++++++++++
 net/core/netdev-genl-gen.h              |  1 +
 net/core/netdev-genl.c                  |  6 ++++++
 tools/include/uapi/linux/netdev.h       |  1 +
 6 files changed, 34 insertions(+)

diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index f5e0750ab71d..c0ef6d0d7786 100644
--- 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 7600bf62dbdf..7eb9571786b8 100644
--- 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 739f7b6506a6..4fc44587f493 100644
--- 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 17d39fd64c94..cf3fad74511f 100644
--- 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 b64c614a00c4..5e42f800dfcf 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -934,6 +934,12 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info)
 	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 7600bf62dbdf..7eb9571786b8 100644
--- 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)
-- 
2.49.0.777.g153de2bbd5-goog