• Martin KaFai Lau's avatar
    inet_diag: Refactor inet_sk_diag_fill(), dump(), and dump_one() · 5682d393
    Martin KaFai Lau authored
    In a latter patch, there is a need to update "cb->min_dump_alloc"
    in inet_sk_diag_fill() as it learns the diffierent bpf_sk_storages
    stored in a sk while dumping all sk(s) (e.g. tcp_hashinfo).
    
    The inet_sk_diag_fill() currently does not take the "cb" as an argument.
    One of the reason is inet_sk_diag_fill() is used by both dump_one()
    and dump() (which belong to the "struct inet_diag_handler".  The dump_one()
    interface does not pass the "cb" along.
    
    This patch is to make dump_one() pass a "cb".  The "cb" is created in
    inet_diag_cmd_exact().  The "nlh" and "in_skb" are stored in "cb" as
    the dump() interface does.  The total number of args in
    inet_sk_diag_fill() is also cut from 10 to 7 and
    that helps many callers to pass fewer args.
    
    In particular,
    "struct user_namespace *user_ns", "u32 pid", and "u32 seq"
    can be replaced by accessing "cb->nlh" and "cb->skb".
    
    A similar argument reduction is also made to
    inet_twsk_diag_fill() and inet_req_diag_fill().
    
    inet_csk_diag_dump() and inet_csk_diag_fill() are also removed.
    They are mostly equivalent to inet_sk_diag_fill().  Their repeated
    usages are very limited.  Thus, inet_sk_diag_fill() is directly used
    in those occasions.
    Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
    Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
    Acked-by: default avatarSong Liu <songliubraving@fb.com>
    Link: https://lore.kernel.org/bpf/20200225230409.1975173-1-kafai@fb.com
    5682d393
udp_diag.c 7.09 KB