From 7e6897f95935973c3253fd756135b5ea58043dc8 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Fri, 13 Dec 2019 18:51:09 +0100 Subject: bpf, xdp: Start using the BPF dispatcher for XDP MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit adds a BPF dispatcher for XDP. The dispatcher is updated from the XDP control-path, dev_xdp_install(), and used when an XDP program is run via bpf_prog_run_xdp(). Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191213175112.30208-4-bjorn.topel@gmail.com --- net/core/dev.c | 19 ++++++++++++++++++- net/core/filter.c | 8 ++++++++ 2 files changed, 26 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/core/dev.c b/net/core/dev.c index 2c277b8aba38..255d3cf35360 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -8542,7 +8542,17 @@ static int dev_xdp_install(struct net_device *dev, bpf_op_t bpf_op, struct netlink_ext_ack *extack, u32 flags, struct bpf_prog *prog) { + bool non_hw = !(flags & XDP_FLAGS_HW_MODE); + struct bpf_prog *prev_prog = NULL; struct netdev_bpf xdp; + int err; + + if (non_hw) { + prev_prog = bpf_prog_by_id(__dev_xdp_query(dev, bpf_op, + XDP_QUERY_PROG)); + if (IS_ERR(prev_prog)) + prev_prog = NULL; + } memset(&xdp, 0, sizeof(xdp)); if (flags & XDP_FLAGS_HW_MODE) @@ -8553,7 +8563,14 @@ static int dev_xdp_install(struct net_device *dev, bpf_op_t bpf_op, xdp.flags = flags; xdp.prog = prog; - return bpf_op(dev, &xdp); + err = bpf_op(dev, &xdp); + if (!err && non_hw) + bpf_prog_change_xdp(prev_prog, prog); + + if (prev_prog) + bpf_prog_put(prev_prog); + + return err; } static void dev_xdp_uninstall(struct net_device *dev) diff --git a/net/core/filter.c b/net/core/filter.c index f1e703eed3d2..a411f7835dee 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8940,3 +8940,11 @@ const struct bpf_verifier_ops sk_reuseport_verifier_ops = { const struct bpf_prog_ops sk_reuseport_prog_ops = { }; #endif /* CONFIG_INET */ + +DEFINE_BPF_DISPATCHER(bpf_dispatcher_xdp) + +void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog) +{ + bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(bpf_dispatcher_xdp), + prev_prog, prog); +} -- cgit