We will call sock_reuseport.prog for socket migration in the next commit, so the eBPF program has to know which listener is closing to select a new listener.
We can currently get a unique ID of each listener in the userspace by calling bpf_map_lookup_elem() for BPF_MAP_TYPE_REUSEPORT_SOCKARRAY map. This patch makes the pointer of sk available in sk_reuseport_md so that we can get the ID by BPF_FUNC_get_socket_cookie() in the eBPF program. Link: https://lore.kernel.org/netdev/20201119001154.kapwihc2plp4f...@kafai-mbp.dhcp.thefacebook.com/ Suggested-by: Martin KaFai Lau <ka...@fb.com> Signed-off-by: Kuniyuki Iwashima <kun...@amazon.co.jp> --- include/uapi/linux/bpf.h | 1 + net/core/filter.c | 10 ++++++++++ tools/include/uapi/linux/bpf.h | 1 + 3 files changed, 12 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 49371eba98ba..ab8584701334 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5299,6 +5299,7 @@ struct sk_reuseport_md { __u32 ip_protocol; /* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */ __u32 bind_inany; /* Is sock bound to an INANY address? */ __u32 hash; /* A hash of the packet 4 tuples */ + __bpf_md_ptr(struct bpf_sock *, sk); }; #define BPF_TAG_SIZE 8 diff --git a/net/core/filter.c b/net/core/filter.c index cae56d08a670..3d0f989f5d38 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -10135,6 +10135,8 @@ sk_reuseport_func_proto(enum bpf_func_id func_id, return &sk_reuseport_load_bytes_proto; case BPF_FUNC_skb_load_bytes_relative: return &sk_reuseport_load_bytes_relative_proto; + case BPF_FUNC_get_socket_cookie: + return &bpf_get_socket_ptr_cookie_proto; default: return bpf_base_func_proto(func_id); } @@ -10164,6 +10166,10 @@ sk_reuseport_is_valid_access(int off, int size, case offsetof(struct sk_reuseport_md, hash): return size == size_default; + case offsetof(struct sk_reuseport_md, sk): + info->reg_type = ARG_PTR_TO_SOCKET; + return size == sizeof(__u64); + /* Fields that allow narrowing */ case bpf_ctx_range(struct sk_reuseport_md, eth_protocol): if (size < sizeof_field(struct sk_buff, protocol)) @@ -10236,6 +10242,10 @@ static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type, case offsetof(struct sk_reuseport_md, bind_inany): SK_REUSEPORT_LOAD_FIELD(bind_inany); break; + + case offsetof(struct sk_reuseport_md, sk): + SK_REUSEPORT_LOAD_FIELD(sk); + break; } return insn - insn_buf; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 69902603012c..5fd94d632792 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5293,6 +5293,7 @@ struct sk_reuseport_md { __u32 ip_protocol; /* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */ __u32 bind_inany; /* Is sock bound to an INANY address? */ __u32 hash; /* A hash of the packet 4 tuples */ + __bpf_md_ptr(struct bpf_sock *, sk); }; #define BPF_TAG_SIZE 8 -- 2.30.2
