From 6fdce8a496beaaa74feb896800f985f1dc2bfa46 Mon Sep 17 00:00:00 2001 From: Brenden Blanco Date: Tue, 19 Jul 2016 12:16:48 -0700 Subject: [PATCH] net: add ndo to setup/query xdp prog in adapter rx Add one new netdev op for drivers implementing the BPF_PROG_TYPE_XDP filter. The single op is used for both setup/query of the xdp program, modelled after ndo_setup_tc. Change-Id: Ie46dec0b47e417e97d5fed19d7f2b143eab4ea73 Signed-off-by: Brenden Blanco Signed-off-by: David S. Miller --- include/linux/netdevice.h | 35 +++++++++++++++++++++++++++++++++++ net/core/dev.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 68 insertions(+) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index f8fcdc3fd7b6..18d0a5beac0c 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -60,6 +60,7 @@ struct wireless_dev; /* 802.15.4 specific */ struct wpan_dev; struct mpls_dev; +struct bpf_prog; void netdev_set_default_ethtool_ops(struct net_device *dev, const struct ethtool_ops *ops); @@ -777,6 +778,34 @@ static inline bool netdev_phys_item_id_same(struct netdev_phys_item_id *a, typedef u16 (*select_queue_fallback_t)(struct net_device *dev, struct sk_buff *skb); +/* These structures hold the attributes of xdp state that are being passed + * to the netdevice through the xdp op. + */ +enum xdp_netdev_command { + /* Set or clear a bpf program used in the earliest stages of packet + * rx. The prog will have been loaded as BPF_PROG_TYPE_XDP. The callee + * is responsible for calling bpf_prog_put on any old progs that are + * stored. In case of error, the callee need not release the new prog + * reference, but on success it takes ownership and must bpf_prog_put + * when it is no longer used. + */ + XDP_SETUP_PROG, + /* Check if a bpf program is set on the device. The callee should + * return true if a program is currently attached and running. + */ + XDP_QUERY_PROG, +}; + +struct netdev_xdp { + enum xdp_netdev_command command; + union { + /* XDP_SETUP_PROG */ + struct bpf_prog *prog; + /* XDP_QUERY_PROG */ + bool prog_attached; + }; +}; + /* * This structure defines the management hooks for network devices. * The following hooks can be defined; unless noted otherwise, they are @@ -1065,6 +1094,9 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev, * appropriate rx headroom value allows avoiding skb head copy on * forward. Setting a negative value reset the rx headroom to the * default value. + * int (*ndo_xdp)(struct net_device *dev, struct netdev_xdp *xdp); + * This function is used to set or query state related to XDP on the + * netdevice. See definition of enum xdp_netdev_command for details. * */ struct net_device_ops { @@ -1244,6 +1276,8 @@ struct net_device_ops { struct sk_buff *skb); void (*ndo_set_rx_headroom)(struct net_device *dev, int needed_headroom); + int (*ndo_xdp)(struct net_device *dev, + struct netdev_xdp *xdp); }; /** @@ -3168,6 +3202,7 @@ int dev_get_phys_port_id(struct net_device *dev, int dev_get_phys_port_name(struct net_device *dev, char *name, size_t len); int dev_change_proto_down(struct net_device *dev, bool proto_down); +int dev_change_xdp_fd(struct net_device *dev, int fd); struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev); struct sk_buff *dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, struct netdev_queue *txq, int *ret); diff --git a/net/core/dev.c b/net/core/dev.c index 590d459caf95..338b109ce79b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -95,6 +95,7 @@ #include #include #include +#include #include #include #include @@ -6321,6 +6322,38 @@ int dev_change_proto_down(struct net_device *dev, bool proto_down) } EXPORT_SYMBOL(dev_change_proto_down); +/** + * dev_change_xdp_fd - set or clear a bpf program for a device rx path + * @dev: device + * @fd: new program fd or negative value to clear + * + * Set or clear a bpf program for a device + */ +int dev_change_xdp_fd(struct net_device *dev, int fd) +{ + const struct net_device_ops *ops = dev->netdev_ops; + struct bpf_prog *prog = NULL; + struct netdev_xdp xdp = {}; + int err; + + if (!ops->ndo_xdp) + return -EOPNOTSUPP; + if (fd >= 0) { + prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_XDP); + if (IS_ERR(prog)) + return PTR_ERR(prog); + } + + xdp.command = XDP_SETUP_PROG; + xdp.prog = prog; + err = ops->ndo_xdp(dev, &xdp); + if (err < 0 && prog) + bpf_prog_put(prog); + + return err; +} +EXPORT_SYMBOL(dev_change_xdp_fd); + /** * dev_new_index - allocate an ifindex * @net: the applicable net namespace