Re: [PATCH net-next v7 3/9] net: devmem: TCP tx netlink api

On Tue, Mar 18, 2025 at 1:39 AM Paolo Abeni pabeni@redhat.com wrote:

On 3/8/25 10:40 PM, Mina Almasry wrote:

...

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 36f1152bfac3..e560b05eb528 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: [ "linux/list.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 996ac6a449eb..f27608d6301c 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 e09dd7539ff2..c1fed66e92b9 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 2b774183d31c..6e5f2de4d947 100644 --- a/net/core/netdev-genl.c +++ b/net/core/netdev-genl.c @@ -931,6 +931,12 @@ 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 list_head *priv) { INIT_LIST_HEAD(priv);

I'm sorry, but this chunck does not apply cleanly anymore.

Please rebase.

Disclaimer: unfortunately I must note that due to the long backlog pending and the upcoming merge window, I'm unsure I'll be able to process the next revision before the net-next closing.

Thanks Paolo. I have also been under the weather the last couple of days so I haven't even been able to repost. I guess I'll repost after the merge window if netdev closes today.

-- Thanks, Mina