From: Jakub Kicinski <kuba@xxxxxxxxxx>
Add a Netlink spec-compatible family for netdevs.
This is a very simple implementation without much
thought going into it.
It allows us to reap all the benefits of Netlink specs,
one can use the generic client to issue the commands:
$ ./cli.py --spec netdev.yaml --dump dev_get
[{'ifindex': 1, 'xdp-features': set()},
{'ifindex': 2, 'xdp-features': {'basic', 'ndo-xmit', 'redirect'}},
{'ifindex': 3, 'xdp-features': {'rx-sg'}}]
the generic python library does not have flags-by-name
support, yet, but we also don't have to carry strings
in the messages, as user space can get the names from
the spec.
Co-developed-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Co-developed-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
Co-developed-by: Marek Majtyka <alardam@xxxxxxxxx>
Signed-off-by: Marek Majtyka <alardam@xxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
---
Documentation/netlink/specs/netdev.yaml | 100 +++++++++++++
include/linux/netdevice.h | 3 +
include/net/xdp.h | 3 +
include/uapi/linux/netdev.h | 59 ++++++++
net/core/Makefile | 3 +-
net/core/dev.c | 1 +
net/core/netdev-genl-gen.c | 48 +++++++
net/core/netdev-genl-gen.h | 23 +++
net/core/netdev-genl.c | 179 ++++++++++++++++++++++++
tools/include/uapi/linux/netdev.h | 59 ++++++++
10 files changed, 477 insertions(+), 1 deletion(-)
create mode 100644 Documentation/netlink/specs/netdev.yaml
create mode 100644 include/uapi/linux/netdev.h
create mode 100644 net/core/netdev-genl-gen.c
create mode 100644 net/core/netdev-genl-gen.h
create mode 100644 net/core/netdev-genl.c
create mode 100644 tools/include/uapi/linux/netdev.h
diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
new file mode 100644
index 000000000000..b4dcdae54ffd
--- /dev/null
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -0,0 +1,100 @@
+name: netdev
+
+doc:
+ netdev configuration over generic netlink.
+
+definitions:
+ -
+ type: flags
+ name: xdp-act
+ entries:
+ -
+ name: basic
+ doc:
+ XDP feautues set supported by all drivers
+ (XDP_ABORTED, XDP_DROP, XDP_PASS, XDP_TX)
+ -
+ name: redirect
+ doc:
+ The netdev supports XDP_REDIRECT
+ -
+ name: ndo-xmit
+ doc:
+ This feature informs if netdev implements ndo_xdp_xmit callback.
+ -
+ name: xsk-zerocopy
+ doc:
+ This feature informs if netdev supports AF_XDP in zero copy mode.
+ -
+ name: hw-offload
+ doc:
+ This feature informs if netdev supports XDP hw oflloading.
+ -
+ name: rx-sg
+ doc:
+ This feature informs if netdev implements non-linear XDP buffer
+ support in the driver napi callback.
+ -
+ name: ndo-xmit-sg
+ doc:
+ This feature informs if netdev implements non-linear XDP buffer
+ support in ndo_xdp_xmit callback.
+
+attribute-sets:
+ -
+ name: dev
+ attributes:
+ -
+ name: ifindex
+ doc: netdev ifindex
+ type: u32
+ value: 1
+ checks:
+ min: 1
+ -
+ name: pad
+ type: pad
+ -
+ name: xdp-features
+ doc: Bitmask of enabled xdp-features.
+ type: u64
+ enum: xdp-act
+ enum-as-flags: true
+
+operations:
+ list:
+ -
+ name: dev-get
+ doc: Get / dump information about a netdev.
+ value: 1
+ attribute-set: dev
+ do:
+ request:
+ attributes:
+ - ifindex
+ reply: &dev-all
+ attributes:
+ - ifindex
+ - xdp-features
+ dump:
+ reply: *dev-all
+ -
+ name: dev-add-ntf
+ doc: Notification about device appearing.
+ notify: dev-get
+ mcgrp: mgmt
+ -
+ name: dev-del-ntf
+ doc: Notification about device disappearing.
+ notify: dev-get
+ mcgrp: mgmt
+ -
+ name: dev-change-ntf
+ doc: Notification about device configuration being changed.
+ notify: dev-get
+ mcgrp: mgmt
+
+mcast-groups:
+ list:
+ -
+ name: mgmt
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 90f2be194bc5..2cbe9a6ede76 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -47,6 +47,7 @@
#include <uapi/linux/netdevice.h>
#include <uapi/linux/if_bonding.h>
#include <uapi/linux/pkt_cls.h>
+#include <uapi/linux/netdev.h>
#include <linux/hashtable.h>
#include <linux/rbtree.h>
#include <net/net_trackers.h>
@@ -2055,6 +2056,7 @@ struct net_device {
/* Read-mostly cache-line for fast-path access */
unsigned int flags;
+ xdp_features_t xdp_features;
unsigned long long priv_flags;
const struct net_device_ops *netdev_ops;
const struct xdp_metadata_ops *xdp_metadata_ops;
@@ -2839,6 +2841,7 @@ enum netdev_cmd {
NETDEV_OFFLOAD_XSTATS_DISABLE,
NETDEV_OFFLOAD_XSTATS_REPORT_USED,
NETDEV_OFFLOAD_XSTATS_REPORT_DELTA,
+ NETDEV_XDP_FEAT_CHANGE,
};
const char *netdev_cmd_to_name(enum netdev_cmd cmd);
diff --git a/include/net/xdp.h b/include/net/xdp.h
index 91292aa13bc0..8d1c86914f4c 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -7,6 +7,7 @@
#define __LINUX_NET_XDP_H__
#include <linux/skbuff.h> /* skb_shared_info */
+#include <uapi/linux/netdev.h>
/**
* DOC: XDP RX-queue information
@@ -43,6 +44,8 @@ enum xdp_mem_type {
MEM_TYPE_MAX,
};
+typedef u32 xdp_features_t;
+
/* XDP flags for ndo_xdp_xmit */
#define XDP_XMIT_FLUSH (1U << 0) /* doorbell signal consumer */
#define XDP_XMIT_FLAGS_MASK XDP_XMIT_FLUSH
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
new file mode 100644
index 000000000000..9ee459872600
--- /dev/null
+++ b/include/uapi/linux/netdev.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Do not edit directly, auto-generated from: */
+/* Documentation/netlink/specs/netdev.yaml */
+/* YNL-GEN uapi header */
+
+#ifndef _UAPI_LINUX_NETDEV_H
+#define _UAPI_LINUX_NETDEV_H
+
+#define NETDEV_FAMILY_NAME "netdev"
+#define NETDEV_FAMILY_VERSION 1
+
+/**
+ * enum netdev_xdp_act
+ * @NETDEV_XDP_ACT_BASIC: XDP feautues set supported by all drivers
+ * (XDP_ABORTED, XDP_DROP, XDP_PASS, XDP_TX)
+ * @NETDEV_XDP_ACT_REDIRECT: The netdev supports XDP_REDIRECT
+ * @NETDEV_XDP_ACT_NDO_XMIT: This feature informs if netdev implements
+ * ndo_xdp_xmit callback.
+ * @NETDEV_XDP_ACT_XSK_ZEROCOPY: This feature informs if netdev supports AF_XDP
+ * in zero copy mode.
+ * @NETDEV_XDP_ACT_HW_OFFLOAD: This feature informs if netdev supports XDP hw
+ * oflloading.
+ * @NETDEV_XDP_ACT_RX_SG: This feature informs if netdev implements non-linear
+ * XDP buffer support in the driver napi callback.
+ * @NETDEV_XDP_ACT_NDO_XMIT_SG: This feature informs if netdev implements
+ * non-linear XDP buffer support in ndo_xdp_xmit callback.
+ */
+enum netdev_xdp_act {
+ NETDEV_XDP_ACT_BASIC = 1,
+ NETDEV_XDP_ACT_REDIRECT = 2,
+ NETDEV_XDP_ACT_NDO_XMIT = 4,
+ NETDEV_XDP_ACT_XSK_ZEROCOPY = 8,
+ NETDEV_XDP_ACT_HW_OFFLOAD = 16,
+ NETDEV_XDP_ACT_RX_SG = 32,
+ NETDEV_XDP_ACT_NDO_XMIT_SG = 64,
+};
+
+enum {
+ NETDEV_A_DEV_IFINDEX = 1,
+ NETDEV_A_DEV_PAD,
+ NETDEV_A_DEV_XDP_FEATURES,
+
+ __NETDEV_A_DEV_MAX,
+ NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_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_MAX,
+ NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
+};
+
+#define NETDEV_MCGRP_MGMT "mgmt"
+
+#endif /* _UAPI_LINUX_NETDEV_H */
diff --git a/net/core/Makefile b/net/core/Makefile
index 10edd66a8a37..8f367813bc68 100644
--- a/net/core/Makefile
+++ b/net/core/Makefile
@@ -12,7 +12,8 @@ obj-$(CONFIG_SYSCTL) += sysctl_net_core.o
obj-y += dev.o dev_addr_lists.o dst.o netevent.o \
neighbour.o rtnetlink.o utils.o link_watch.o filter.o \
sock_diag.o dev_ioctl.o tso.o sock_reuseport.o \
- fib_notifier.o xdp.o flow_offload.o gro.o
+ fib_notifier.o xdp.o flow_offload.o gro.o \
+ netdev-genl.o netdev-genl-gen.o
obj-$(CONFIG_NETDEV_ADDR_LIST_TEST) += dev_addr_lists_test.o
diff --git a/net/core/dev.c b/net/core/dev.c
index e66da626df84..2df1c940aa14 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1614,6 +1614,7 @@ const char *netdev_cmd_to_name(enum netdev_cmd cmd)
N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO)
N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE)
N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA)
+ N(XDP_FEAT_CHANGE)
}
#undef N
return "UNKNOWN_NETDEV_EVENT";
diff --git a/net/core/netdev-genl-gen.c b/net/core/netdev-genl-gen.c
new file mode 100644
index 000000000000..48812ec843f5
--- /dev/null
+++ b/net/core/netdev-genl-gen.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/* Do not edit directly, auto-generated from: */
+/* Documentation/netlink/specs/netdev.yaml */
+/* YNL-GEN kernel source */
+
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include "netdev-genl-gen.h"
+
+#include <linux/netdev.h>
+
+/* NETDEV_CMD_DEV_GET - do */
+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),
+};
+
+/* Ops table for netdev */
+static const struct genl_split_ops netdev_nl_ops[2] = {
+ {
+ .cmd = NETDEV_CMD_DEV_GET,
+ .doit = netdev_nl_dev_get_doit,
+ .policy = netdev_dev_get_nl_policy,
+ .maxattr = NETDEV_A_DEV_IFINDEX,
+ .flags = GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = NETDEV_CMD_DEV_GET,
+ .dumpit = netdev_nl_dev_get_dumpit,
+ .flags = GENL_CMD_CAP_DUMP,
+ },
+};
+
+static const struct genl_multicast_group netdev_nl_mcgrps[] = {
+ [NETDEV_NLGRP_MGMT] = { "mgmt", },
+};
+
+struct genl_family netdev_nl_family __ro_after_init = {
+ .name = NETDEV_FAMILY_NAME,
+ .version = NETDEV_FAMILY_VERSION,
+ .netnsok = true,
+ .parallel_ops = true,
+ .module = THIS_MODULE,
+ .split_ops = netdev_nl_ops,
+ .n_split_ops = ARRAY_SIZE(netdev_nl_ops),
+ .mcgrps = netdev_nl_mcgrps,
+ .n_mcgrps = ARRAY_SIZE(netdev_nl_mcgrps),
+};
diff --git a/net/core/netdev-genl-gen.h b/net/core/netdev-genl-gen.h
new file mode 100644
index 000000000000..b16dc7e026bb
--- /dev/null
+++ b/net/core/netdev-genl-gen.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+/* Do not edit directly, auto-generated from: */
+/* Documentation/netlink/specs/netdev.yaml */
+/* YNL-GEN kernel header */
+
+#ifndef _LINUX_NETDEV_GEN_H
+#define _LINUX_NETDEV_GEN_H
+
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include <linux/netdev.h>
+
+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);
+
+enum {
+ NETDEV_NLGRP_MGMT,
+};
+
+extern struct genl_family netdev_nl_family;
+
+#endif /* _LINUX_NETDEV_GEN_H */
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
new file mode 100644
index 000000000000..a4270fafdf11
--- /dev/null
+++ b/net/core/netdev-genl.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/netdevice.h>
+#include <linux/notifier.h>
+#include <linux/rtnetlink.h>
+#include <net/net_namespace.h>
+#include <net/sock.h>
+
+#include "netdev-genl-gen.h"
+
+static int
+netdev_nl_dev_fill(struct net_device *netdev, struct sk_buff *rsp,
+ u32 portid, u32 seq, int flags, u32 cmd)
+{
+ void *hdr;
+
+ hdr = genlmsg_put(rsp, portid, seq, &netdev_nl_family, flags, cmd);
+ if (!hdr)
+ return -EMSGSIZE;
+
+ if (nla_put_u32(rsp, NETDEV_A_DEV_IFINDEX, netdev->ifindex) ||
+ nla_put_u64_64bit(rsp, NETDEV_A_DEV_XDP_FEATURES,
+ netdev->xdp_features, NETDEV_A_DEV_PAD)) {
+ genlmsg_cancel(rsp, hdr);
+ return -EINVAL;
+ }
+
+ genlmsg_end(rsp, hdr);
+
+ return 0;
+}
+
+static void
+netdev_genl_dev_notify(struct net_device *netdev, int cmd)
+{
+ struct sk_buff *ntf;
+
+ if (!genl_has_listeners(&netdev_nl_family, dev_net(netdev),
+ NETDEV_NLGRP_MGMT))
+ return;
+
+ ntf = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!ntf)
+ return;
+
+ if (netdev_nl_dev_fill(netdev, ntf, 0, 0, 0, cmd)) {
+ nlmsg_free(ntf);
+ return;
+ }
+
+ genlmsg_multicast_netns(&netdev_nl_family, dev_net(netdev), ntf,
+ 0, NETDEV_NLGRP_MGMT, GFP_KERNEL);
+}
+
+int netdev_nl_dev_get_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net_device *netdev;
+ struct sk_buff *rsp;
+ u32 ifindex;
+ int err;
+
+ if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_DEV_IFINDEX))
+ return -EINVAL;
+
+ ifindex = nla_get_u32(info->attrs[NETDEV_A_DEV_IFINDEX]);
+
+ rsp = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!rsp)
+ return -ENOMEM;
+
+ rtnl_lock();
+
+ netdev = __dev_get_by_index(genl_info_net(info), ifindex);
+ if (netdev)
+ err = netdev_nl_dev_fill(netdev, rsp, info->snd_portid,
+ info->snd_seq, 0, info->genlhdr->cmd);
+ else
+ err = -ENODEV;
+
+ rtnl_unlock();
+
+ if (err)
+ goto err_free_msg;
+
+ return genlmsg_reply(rsp, info);
+
+err_free_msg:
+ nlmsg_free(rsp);
+ return err;
+}
+
+int netdev_nl_dev_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct net *net = sock_net(skb->sk);
+ struct net_device *netdev;
+ int idx = 0, s_idx;
+ int h, s_h;
+ int err;
+
+ s_h = cb->args[0];
+ s_idx = cb->args[1];
+
+ rtnl_lock();
+
+ for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
+ struct hlist_head *head;
+
+ idx = 0;
+ head = &net->dev_index_head[h];
+ hlist_for_each_entry(netdev, head, index_hlist) {
+ if (idx < s_idx)
+ goto cont;
+ err = netdev_nl_dev_fill(netdev, skb,
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, 0,
+ NETDEV_CMD_DEV_GET);
+ if (err < 0)
+ break;
+cont:
+ idx++;
+ }
+ }
+
+ rtnl_unlock();
+
+ if (err != -EMSGSIZE)
+ return err;
+
+ cb->args[1] = idx;
+ cb->args[0] = h;
+ cb->seq = net->dev_base_seq;
+
+ return skb->len;
+}
+
+static int netdev_genl_netdevice_event(struct notifier_block *nb,
+ unsigned long event, void *ptr)
+{
+ struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
+
+ switch (event) {
+ case NETDEV_REGISTER:
+ netdev_genl_dev_notify(netdev, NETDEV_CMD_DEV_ADD_NTF);
+ break;
+ case NETDEV_UNREGISTER:
+ netdev_genl_dev_notify(netdev, NETDEV_CMD_DEV_DEL_NTF);
+ break;
+ case NETDEV_XDP_FEAT_CHANGE:
+ netdev_genl_dev_notify(netdev, NETDEV_CMD_DEV_CHANGE_NTF);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block netdev_genl_nb = {
+ .notifier_call = netdev_genl_netdevice_event,
+};
+
+static int __init netdev_genl_init(void)
+{
+ int err;
+
+ err = register_netdevice_notifier(&netdev_genl_nb);
+ if (err)
+ return err;
+
+ err = genl_register_family(&netdev_nl_family);
+ if (err)
+ goto err_unreg_ntf;
+
+ return 0;
+
+err_unreg_ntf:
+ unregister_netdevice_notifier(&netdev_genl_nb);
+ return err;
+}
+
+subsys_initcall(netdev_genl_init);
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
new file mode 100644
index 000000000000..9ee459872600
--- /dev/null
+++ b/tools/include/uapi/linux/netdev.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Do not edit directly, auto-generated from: */
+/* Documentation/netlink/specs/netdev.yaml */
+/* YNL-GEN uapi header */
+
+#ifndef _UAPI_LINUX_NETDEV_H
+#define _UAPI_LINUX_NETDEV_H
+
+#define NETDEV_FAMILY_NAME "netdev"
+#define NETDEV_FAMILY_VERSION 1
+
+/**
+ * enum netdev_xdp_act
+ * @NETDEV_XDP_ACT_BASIC: XDP feautues set supported by all drivers
+ * (XDP_ABORTED, XDP_DROP, XDP_PASS, XDP_TX)
+ * @NETDEV_XDP_ACT_REDIRECT: The netdev supports XDP_REDIRECT
+ * @NETDEV_XDP_ACT_NDO_XMIT: This feature informs if netdev implements
+ * ndo_xdp_xmit callback.
+ * @NETDEV_XDP_ACT_XSK_ZEROCOPY: This feature informs if netdev supports AF_XDP
+ * in zero copy mode.
+ * @NETDEV_XDP_ACT_HW_OFFLOAD: This feature informs if netdev supports XDP hw
+ * oflloading.
+ * @NETDEV_XDP_ACT_RX_SG: This feature informs if netdev implements non-linear
+ * XDP buffer support in the driver napi callback.
+ * @NETDEV_XDP_ACT_NDO_XMIT_SG: This feature informs if netdev implements
+ * non-linear XDP buffer support in ndo_xdp_xmit callback.
+ */
+enum netdev_xdp_act {
+ NETDEV_XDP_ACT_BASIC = 1,
+ NETDEV_XDP_ACT_REDIRECT = 2,
+ NETDEV_XDP_ACT_NDO_XMIT = 4,
+ NETDEV_XDP_ACT_XSK_ZEROCOPY = 8,
+ NETDEV_XDP_ACT_HW_OFFLOAD = 16,
+ NETDEV_XDP_ACT_RX_SG = 32,
+ NETDEV_XDP_ACT_NDO_XMIT_SG = 64,
+};
+
+enum {
+ NETDEV_A_DEV_IFINDEX = 1,
+ NETDEV_A_DEV_PAD,
+ NETDEV_A_DEV_XDP_FEATURES,
+
+ __NETDEV_A_DEV_MAX,
+ NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_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_MAX,
+ NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
+};
+
+#define NETDEV_MCGRP_MGMT "mgmt"
+
+#endif /* _UAPI_LINUX_NETDEV_H */
--
2.39.1
