From 58038695e62b4473e4d70e1503933579c640cd52 Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Thu, 15 Jun 2017 17:29:09 -0700 Subject: [PATCH] net: Add IFLA_XDP_PROG_ID Expose prog_id through IFLA_XDP_PROG_ID. This patch makes modification to generic_xdp. The later patches will modify other xdp-supported drivers. prog_id is added to struct net_dev_xdp. iproute2 patch will be followed. Here is how the 'ip link' will look like: > ip link show eth0 3: eth0: mtu 1500 xdp(prog_id:1) qdisc fq_codel state UP mode DEFAULT group default qlen 1000 Signed-off-by: Martin KaFai Lau Acked-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- include/linux/netdevice.h | 7 +++++-- include/uapi/linux/if_link.h | 1 + net/core/dev.c | 19 +++++++++++-------- net/core/rtnetlink.c | 27 +++++++++++++++++++++------ 4 files changed, 38 insertions(+), 16 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ad98a83f1332..7c7118b3bd69 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -824,7 +824,10 @@ struct netdev_xdp { struct netlink_ext_ack *extack; }; /* XDP_QUERY_PROG */ - bool prog_attached; + struct { + bool prog_attached; + u32 prog_id; + }; }; }; @@ -3302,7 +3305,7 @@ struct sk_buff *dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, typedef int (*xdp_op_t)(struct net_device *dev, struct netdev_xdp *xdp); int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, int fd, u32 flags); -bool __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op); +bool __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op, u32 *prog_id); int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb); int dev_forward_skb(struct net_device *dev, struct sk_buff *skb); diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 8ed679fe603f..dd88375a6580 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -907,6 +907,7 @@ enum { IFLA_XDP_FD, IFLA_XDP_ATTACHED, IFLA_XDP_FLAGS, + IFLA_XDP_PROG_ID, __IFLA_XDP_MAX, }; diff --git a/net/core/dev.c b/net/core/dev.c index 8658074ecad6..b8d6dd9e8b5c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4342,13 +4342,12 @@ static struct static_key generic_xdp_needed __read_mostly; static int generic_xdp_install(struct net_device *dev, struct netdev_xdp *xdp) { + struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); struct bpf_prog *new = xdp->prog; int ret = 0; switch (xdp->command) { - case XDP_SETUP_PROG: { - struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); - + case XDP_SETUP_PROG: rcu_assign_pointer(dev->xdp_prog, new); if (old) bpf_prog_put(old); @@ -4360,10 +4359,10 @@ static int generic_xdp_install(struct net_device *dev, struct netdev_xdp *xdp) dev_disable_lro(dev); } break; - } case XDP_QUERY_PROG: - xdp->prog_attached = !!rcu_access_pointer(dev->xdp_prog); + xdp->prog_attached = !!old; + xdp->prog_id = old ? old->aux->id : 0; break; default: @@ -6937,7 +6936,8 @@ int dev_change_proto_down(struct net_device *dev, bool proto_down) } EXPORT_SYMBOL(dev_change_proto_down); -bool __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op) +bool __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op, + u32 *prog_id) { struct netdev_xdp xdp; @@ -6946,6 +6946,9 @@ bool __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op) /* Query must always succeed. */ WARN_ON(xdp_op(dev, &xdp) < 0); + if (prog_id) + *prog_id = xdp.prog_id; + return xdp.prog_attached; } @@ -6991,10 +6994,10 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, xdp_chk = generic_xdp_install; if (fd >= 0) { - if (xdp_chk && __dev_xdp_attached(dev, xdp_chk)) + if (xdp_chk && __dev_xdp_attached(dev, xdp_chk, NULL)) return -EEXIST; if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && - __dev_xdp_attached(dev, xdp_op)) + __dev_xdp_attached(dev, xdp_op, NULL)) return -EBUSY; prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_XDP); diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 2769ad9834d1..3aa57848a895 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -39,6 +39,7 @@ #include #include #include +#include #include @@ -899,7 +900,8 @@ static size_t rtnl_port_size(const struct net_device *dev, static size_t rtnl_xdp_size(void) { size_t xdp_size = nla_total_size(0) + /* nest IFLA_XDP */ - nla_total_size(1); /* XDP_ATTACHED */ + nla_total_size(1) + /* XDP_ATTACHED */ + nla_total_size(4); /* XDP_PROG_ID */ return xdp_size; } @@ -1248,15 +1250,20 @@ static int rtnl_fill_link_ifmap(struct sk_buff *skb, struct net_device *dev) return 0; } -static u8 rtnl_xdp_attached_mode(struct net_device *dev) +static u8 rtnl_xdp_attached_mode(struct net_device *dev, u32 *prog_id) { const struct net_device_ops *ops = dev->netdev_ops; + const struct bpf_prog *generic_xdp_prog; ASSERT_RTNL(); - if (rcu_access_pointer(dev->xdp_prog)) + *prog_id = 0; + generic_xdp_prog = rtnl_dereference(dev->xdp_prog); + if (generic_xdp_prog) { + *prog_id = generic_xdp_prog->aux->id; return XDP_ATTACHED_SKB; - if (ops->ndo_xdp && __dev_xdp_attached(dev, ops->ndo_xdp)) + } + if (ops->ndo_xdp && __dev_xdp_attached(dev, ops->ndo_xdp, prog_id)) return XDP_ATTACHED_DRV; return XDP_ATTACHED_NONE; @@ -1265,6 +1272,7 @@ static u8 rtnl_xdp_attached_mode(struct net_device *dev) static int rtnl_xdp_fill(struct sk_buff *skb, struct net_device *dev) { struct nlattr *xdp; + u32 prog_id; int err; xdp = nla_nest_start(skb, IFLA_XDP); @@ -1272,10 +1280,16 @@ static int rtnl_xdp_fill(struct sk_buff *skb, struct net_device *dev) return -EMSGSIZE; err = nla_put_u8(skb, IFLA_XDP_ATTACHED, - rtnl_xdp_attached_mode(dev)); + rtnl_xdp_attached_mode(dev, &prog_id)); if (err) goto err_cancel; + if (prog_id) { + err = nla_put_u32(skb, IFLA_XDP_PROG_ID, prog_id); + if (err) + goto err_cancel; + } + nla_nest_end(skb, xdp); return 0; @@ -1553,6 +1567,7 @@ static const struct nla_policy ifla_xdp_policy[IFLA_XDP_MAX + 1] = { [IFLA_XDP_FD] = { .type = NLA_S32 }, [IFLA_XDP_ATTACHED] = { .type = NLA_U8 }, [IFLA_XDP_FLAGS] = { .type = NLA_U32 }, + [IFLA_XDP_PROG_ID] = { .type = NLA_U32 }, }; static const struct rtnl_link_ops *linkinfo_to_kind_ops(const struct nlattr *nla) @@ -2225,7 +2240,7 @@ static int do_setlink(const struct sk_buff *skb, if (err < 0) goto errout; - if (xdp[IFLA_XDP_ATTACHED]) { + if (xdp[IFLA_XDP_ATTACHED] || xdp[IFLA_XDP_PROG_ID]) { err = -EINVAL; goto errout; }