[RFC PATCH v3 03/12] net: netdev netlink api to bind dma-buf to a net device
From: Mina Almasry
Date: Sun Nov 05 2023 - 21:44:41 EST
API takes the dma-buf fd as input, and binds it to the netdevice. The
user can specify the rx queues to bind the dma-buf to.
Suggested-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx>
---
Changes in v3:
- Support binding multiple rx rx-queues
---
Documentation/netlink/specs/netdev.yaml | 28 +++++++++++++++
include/uapi/linux/netdev.h | 10 ++++++
net/core/netdev-genl-gen.c | 14 ++++++++
net/core/netdev-genl-gen.h | 1 +
net/core/netdev-genl.c | 6 ++++
tools/include/uapi/linux/netdev.h | 10 ++++++
tools/net/ynl/generated/netdev-user.c | 42 ++++++++++++++++++++++
tools/net/ynl/generated/netdev-user.h | 47 +++++++++++++++++++++++++
8 files changed, 158 insertions(+)
diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index 14511b13f305..2141c5f5c33e 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -86,6 +86,24 @@ attribute-sets:
See Documentation/networking/xdp-rx-metadata.rst for more details.
type: u64
enum: xdp-rx-metadata
+ -
+ name: bind-dmabuf
+ attributes:
+ -
+ name: ifindex
+ doc: netdev ifindex to bind the dma-buf to.
+ type: u32
+ checks:
+ min: 1
+ -
+ name: queues
+ doc: receive queues to bind the dma-buf to.
+ type: u32
+ multi-attr: true
+ -
+ name: dmabuf-fd
+ doc: dmabuf file descriptor to bind.
+ type: u32
operations:
list:
@@ -120,6 +138,16 @@ operations:
doc: Notification about device configuration being changed.
notify: dev-get
mcgrp: mgmt
+ -
+ name: bind-rx
+ doc: Bind dmabuf to netdev
+ attribute-set: bind-dmabuf
+ do:
+ request:
+ attributes:
+ - ifindex
+ - dmabuf-fd
+ - queues
mcast-groups:
list:
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index 2943a151d4f1..2cd367c498c7 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -64,11 +64,21 @@ enum {
NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_MAX - 1)
};
+enum {
+ NETDEV_A_BIND_DMABUF_IFINDEX = 1,
+ NETDEV_A_BIND_DMABUF_QUEUES,
+ NETDEV_A_BIND_DMABUF_DMABUF_FD,
+
+ __NETDEV_A_BIND_DMABUF_MAX,
+ NETDEV_A_BIND_DMABUF_MAX = (__NETDEV_A_BIND_DMABUF_MAX - 1)
+};
+
enum {
NETDEV_CMD_DEV_GET = 1,
NETDEV_CMD_DEV_ADD_NTF,
NETDEV_CMD_DEV_DEL_NTF,
NETDEV_CMD_DEV_CHANGE_NTF,
+ NETDEV_CMD_BIND_RX,
__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 ea9231378aa6..58300efaf4e5 100644
--- a/net/core/netdev-genl-gen.c
+++ b/net/core/netdev-genl-gen.c
@@ -15,6 +15,13 @@ static const struct nla_policy netdev_dev_get_nl_policy[NETDEV_A_DEV_IFINDEX + 1
[NETDEV_A_DEV_IFINDEX] = NLA_POLICY_MIN(NLA_U32, 1),
};
+/* NETDEV_CMD_BIND_RX - do */
+static const struct nla_policy netdev_bind_rx_nl_policy[NETDEV_A_BIND_DMABUF_DMABUF_FD + 1] = {
+ [NETDEV_A_BIND_DMABUF_IFINDEX] = NLA_POLICY_MIN(NLA_U32, 1),
+ [NETDEV_A_BIND_DMABUF_DMABUF_FD] = { .type = NLA_U32, },
+ [NETDEV_A_BIND_DMABUF_QUEUES] = { .type = NLA_U32, },
+};
+
/* Ops table for netdev */
static const struct genl_split_ops netdev_nl_ops[] = {
{
@@ -29,6 +36,13 @@ static const struct genl_split_ops netdev_nl_ops[] = {
.dumpit = netdev_nl_dev_get_dumpit,
.flags = GENL_CMD_CAP_DUMP,
},
+ {
+ .cmd = NETDEV_CMD_BIND_RX,
+ .doit = netdev_nl_bind_rx_doit,
+ .policy = netdev_bind_rx_nl_policy,
+ .maxattr = NETDEV_A_BIND_DMABUF_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 7b370c073e7d..5aaeb435ec08 100644
--- a/net/core/netdev-genl-gen.h
+++ b/net/core/netdev-genl-gen.h
@@ -13,6 +13,7 @@
int netdev_nl_dev_get_doit(struct sk_buff *skb, struct genl_info *info);
int netdev_nl_dev_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
+int netdev_nl_bind_rx_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 fe61f85bcf33..59d3d512d9cc 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -129,6 +129,12 @@ int netdev_nl_dev_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
return skb->len;
}
+/* Stub */
+int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return 0;
+}
+
static int netdev_genl_netdevice_event(struct notifier_block *nb,
unsigned long event, void *ptr)
{
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index 2943a151d4f1..2cd367c498c7 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -64,11 +64,21 @@ enum {
NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_MAX - 1)
};
+enum {
+ NETDEV_A_BIND_DMABUF_IFINDEX = 1,
+ NETDEV_A_BIND_DMABUF_QUEUES,
+ NETDEV_A_BIND_DMABUF_DMABUF_FD,
+
+ __NETDEV_A_BIND_DMABUF_MAX,
+ NETDEV_A_BIND_DMABUF_MAX = (__NETDEV_A_BIND_DMABUF_MAX - 1)
+};
+
enum {
NETDEV_CMD_DEV_GET = 1,
NETDEV_CMD_DEV_ADD_NTF,
NETDEV_CMD_DEV_DEL_NTF,
NETDEV_CMD_DEV_CHANGE_NTF,
+ NETDEV_CMD_BIND_RX,
__NETDEV_CMD_MAX,
NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
diff --git a/tools/net/ynl/generated/netdev-user.c b/tools/net/ynl/generated/netdev-user.c
index b5ffe8cd1144..d5f4c6d4c2b2 100644
--- a/tools/net/ynl/generated/netdev-user.c
+++ b/tools/net/ynl/generated/netdev-user.c
@@ -18,6 +18,7 @@ static const char * const netdev_op_strmap[] = {
[NETDEV_CMD_DEV_ADD_NTF] = "dev-add-ntf",
[NETDEV_CMD_DEV_DEL_NTF] = "dev-del-ntf",
[NETDEV_CMD_DEV_CHANGE_NTF] = "dev-change-ntf",
+ [NETDEV_CMD_BIND_RX] = "bind-rx",
};
const char *netdev_op_str(int op)
@@ -72,6 +73,17 @@ struct ynl_policy_nest netdev_dev_nest = {
.table = netdev_dev_policy,
};
+struct ynl_policy_attr netdev_bind_dmabuf_policy[NETDEV_A_BIND_DMABUF_MAX + 1] = {
+ [NETDEV_A_BIND_DMABUF_IFINDEX] = { .name = "ifindex", .type = YNL_PT_U32, },
+ [NETDEV_A_BIND_DMABUF_QUEUES] = { .name = "queues", .type = YNL_PT_U32, },
+ [NETDEV_A_BIND_DMABUF_DMABUF_FD] = { .name = "dmabuf-fd", .type = YNL_PT_U32, },
+};
+
+struct ynl_policy_nest netdev_bind_dmabuf_nest = {
+ .max_attr = NETDEV_A_BIND_DMABUF_MAX,
+ .table = netdev_bind_dmabuf_policy,
+};
+
/* Common nested types */
/* ============== NETDEV_CMD_DEV_GET ============== */
/* NETDEV_CMD_DEV_GET - do */
@@ -197,6 +209,36 @@ void netdev_dev_get_ntf_free(struct netdev_dev_get_ntf *rsp)
free(rsp);
}
+/* ============== NETDEV_CMD_BIND_RX ============== */
+/* NETDEV_CMD_BIND_RX - do */
+void netdev_bind_rx_req_free(struct netdev_bind_rx_req *req)
+{
+ free(req->queues);
+ free(req);
+}
+
+int netdev_bind_rx(struct ynl_sock *ys, struct netdev_bind_rx_req *req)
+{
+ struct nlmsghdr *nlh;
+ int err;
+
+ nlh = ynl_gemsg_start_req(ys, ys->family_id, NETDEV_CMD_BIND_RX, 1);
+ ys->req_policy = &netdev_bind_dmabuf_nest;
+
+ if (req->_present.ifindex)
+ mnl_attr_put_u32(nlh, NETDEV_A_BIND_DMABUF_IFINDEX, req->ifindex);
+ if (req->_present.dmabuf_fd)
+ mnl_attr_put_u32(nlh, NETDEV_A_BIND_DMABUF_DMABUF_FD, req->dmabuf_fd);
+ for (unsigned int i = 0; i < req->n_queues; i++)
+ mnl_attr_put_u32(nlh, NETDEV_A_BIND_DMABUF_QUEUES, req->queues[i]);
+
+ err = ynl_exec(ys, nlh, NULL);
+ if (err < 0)
+ return -1;
+
+ return 0;
+}
+
static const struct ynl_ntf_info netdev_ntf_info[] = {
[NETDEV_CMD_DEV_ADD_NTF] = {
.alloc_sz = sizeof(struct netdev_dev_get_ntf),
diff --git a/tools/net/ynl/generated/netdev-user.h b/tools/net/ynl/generated/netdev-user.h
index 4fafac879df3..3cf9096d733a 100644
--- a/tools/net/ynl/generated/netdev-user.h
+++ b/tools/net/ynl/generated/netdev-user.h
@@ -87,4 +87,51 @@ struct netdev_dev_get_ntf {
void netdev_dev_get_ntf_free(struct netdev_dev_get_ntf *rsp);
+/* ============== NETDEV_CMD_BIND_RX ============== */
+/* NETDEV_CMD_BIND_RX - do */
+struct netdev_bind_rx_req {
+ struct {
+ __u32 ifindex:1;
+ __u32 dmabuf_fd:1;
+ } _present;
+
+ __u32 ifindex;
+ __u32 dmabuf_fd;
+ unsigned int n_queues;
+ __u32 *queues;
+};
+
+static inline struct netdev_bind_rx_req *netdev_bind_rx_req_alloc(void)
+{
+ return calloc(1, sizeof(struct netdev_bind_rx_req));
+}
+void netdev_bind_rx_req_free(struct netdev_bind_rx_req *req);
+
+static inline void
+netdev_bind_rx_req_set_ifindex(struct netdev_bind_rx_req *req, __u32 ifindex)
+{
+ req->_present.ifindex = 1;
+ req->ifindex = ifindex;
+}
+static inline void
+netdev_bind_rx_req_set_dmabuf_fd(struct netdev_bind_rx_req *req,
+ __u32 dmabuf_fd)
+{
+ req->_present.dmabuf_fd = 1;
+ req->dmabuf_fd = dmabuf_fd;
+}
+static inline void
+__netdev_bind_rx_req_set_queues(struct netdev_bind_rx_req *req, __u32 *queues,
+ unsigned int n_queues)
+{
+ free(req->queues);
+ req->queues = queues;
+ req->n_queues = n_queues;
+}
+
+/*
+ * Bind dmabuf to netdev
+ */
+int netdev_bind_rx(struct ynl_sock *ys, struct netdev_bind_rx_req *req);
+
#endif /* _LINUX_NETDEV_GEN_H */
--
2.42.0.869.gea05f2083d-goog