From 118b4aa25d90d0930611b71dd28a749c67309ccb Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 1 Dec 2017 15:08:55 -0800 Subject: [PATCH] net: xdp: avoid output parameters when querying XDP prog The output parameters will get unwieldy if we want to add more information about the program. Simply pass the entire struct netdev_bpf in. Signed-off-by: Jakub Kicinski Reviewed-by: Simon Horman Reviewed-by: Quentin Monnet Signed-off-by: Daniel Borkmann --- include/linux/netdevice.h | 3 ++- net/core/dev.c | 24 ++++++++++++++---------- net/core/rtnetlink.c | 6 +++++- 3 files changed, 21 insertions(+), 12 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ef789e1d679e..667bdd3ad33e 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3330,7 +3330,8 @@ struct sk_buff *dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, typedef int (*bpf_op_t)(struct net_device *dev, struct netdev_bpf *bpf); int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, int fd, u32 flags); -u8 __dev_xdp_attached(struct net_device *dev, bpf_op_t xdp_op, u32 *prog_id); +void __dev_xdp_query(struct net_device *dev, bpf_op_t xdp_op, + struct netdev_bpf *xdp); 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/net/core/dev.c b/net/core/dev.c index 07ed21d64f92..3f271c9cb5e0 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7073,17 +7073,21 @@ int dev_change_proto_down(struct net_device *dev, bool proto_down) } EXPORT_SYMBOL(dev_change_proto_down); -u8 __dev_xdp_attached(struct net_device *dev, bpf_op_t bpf_op, u32 *prog_id) +void __dev_xdp_query(struct net_device *dev, bpf_op_t bpf_op, + struct netdev_bpf *xdp) +{ + memset(xdp, 0, sizeof(*xdp)); + xdp->command = XDP_QUERY_PROG; + + /* Query must always succeed. */ + WARN_ON(bpf_op(dev, xdp) < 0); +} + +static u8 __dev_xdp_attached(struct net_device *dev, bpf_op_t bpf_op) { struct netdev_bpf xdp; - memset(&xdp, 0, sizeof(xdp)); - xdp.command = XDP_QUERY_PROG; - - /* Query must always succeed. */ - WARN_ON(bpf_op(dev, &xdp) < 0); - if (prog_id) - *prog_id = xdp.prog_id; + __dev_xdp_query(dev, bpf_op, &xdp); return xdp.prog_attached; } @@ -7134,10 +7138,10 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, bpf_chk = generic_xdp_install; if (fd >= 0) { - if (bpf_chk && __dev_xdp_attached(dev, bpf_chk, NULL)) + if (bpf_chk && __dev_xdp_attached(dev, bpf_chk)) return -EEXIST; if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && - __dev_xdp_attached(dev, bpf_op, NULL)) + __dev_xdp_attached(dev, bpf_op)) return -EBUSY; prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index dabba2a91fc8..9c4cb584bfb0 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1261,6 +1261,7 @@ 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; + struct netdev_bpf xdp; ASSERT_RTNL(); @@ -1273,7 +1274,10 @@ static u8 rtnl_xdp_attached_mode(struct net_device *dev, u32 *prog_id) if (!ops->ndo_bpf) return XDP_ATTACHED_NONE; - return __dev_xdp_attached(dev, ops->ndo_bpf, prog_id); + __dev_xdp_query(dev, ops->ndo_bpf, &xdp); + *prog_id = xdp.prog_id; + + return xdp.prog_attached; } static int rtnl_xdp_fill(struct sk_buff *skb, struct net_device *dev)