> On May 3, 2023, at 3:53 PM, Aditi Ghag <aditi.ghag@xxxxxxxxxxxxx> wrote:
>
> This is a preparatory commit to remove the field. The field was
> previously shared between proc fs and BPF UDP socket iterators. As the
> follow-up commits will decouple the implementation for the iterators,
> remove the field. As for BPF socket iterator, filtering of sockets is
> exepected to be done in BPF programs.
>
> Suggested-by: Martin KaFai Lau <martin.lau@xxxxxxxxxx>
> Signed-off-by: Aditi Ghag <aditi.ghag@xxxxxxxxxxxxx>
> ---
> include/net/udp.h | 1 -
> net/ipv4/udp.c | 25 +++++--------------------
> 2 files changed, 5 insertions(+), 21 deletions(-)
>
> diff --git a/include/net/udp.h b/include/net/udp.h
> index de4b528522bb..5cad44318d71 100644
> --- a/include/net/udp.h
> +++ b/include/net/udp.h
> @@ -437,7 +437,6 @@ struct udp_seq_afinfo {
> struct udp_iter_state {
> struct seq_net_private p;
> int bucket;
> - struct udp_seq_afinfo *bpf_seq_afinfo;
> };
>
> void *udp_seq_start(struct seq_file *seq, loff_t *pos);
> diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
> index c426ebafeb13..9f8c1554a9e4 100644
> --- a/net/ipv4/udp.c
> +++ b/net/ipv4/udp.c
> @@ -2993,14 +2993,16 @@ static bool seq_sk_match(struct seq_file *seq, const struct sock *sk)
> net_eq(sock_net(sk), seq_file_net(seq)));
> }
>
> +static const struct seq_operations bpf_iter_udp_seq_ops;
>> net/ipv4/udp.c:3001:36: warning: 'bpf_iter_udp_seq_ops' defined but not used [-Wunused-const-variable=]
3001 | static const struct seq_operations bpf_iter_udp_seq_ops;
| ^~~~~~~~~~~~~~~~~~~~
This would have to be wrapped with ifdef too.
> static struct udp_table *udp_get_table_seq(struct seq_file *seq,
> struct net *net)
> {
> - const struct udp_iter_state *state = seq->private;
> const struct udp_seq_afinfo *afinfo;
>
> - if (state->bpf_seq_afinfo)
> +#ifdef CONFIG_BPF_SYSCALL
> + if (seq->op == &bpf_iter_udp_seq_ops)
> return net->ipv4.udp_table;
> +#endif
>
> afinfo = pde_data(file_inode(seq->file));
> return afinfo->udp_table ? : net->ipv4.udp_table;
> @@ -3424,28 +3426,11 @@ DEFINE_BPF_ITER_FUNC(udp, struct bpf_iter_meta *meta,
>
> static int bpf_iter_init_udp(void *priv_data, struct bpf_iter_aux_info *aux)
> {
> - struct udp_iter_state *st = priv_data;
> - struct udp_seq_afinfo *afinfo;
> - int ret;
> -
> - afinfo = kmalloc(sizeof(*afinfo), GFP_USER | __GFP_NOWARN);
> - if (!afinfo)
> - return -ENOMEM;
> -
> - afinfo->family = AF_UNSPEC;
> - afinfo->udp_table = NULL;
> - st->bpf_seq_afinfo = afinfo;
> - ret = bpf_iter_init_seq_net(priv_data, aux);
> - if (ret)
> - kfree(afinfo);
> - return ret;
> + return bpf_iter_init_seq_net(priv_data, aux);
> }
>
> static void bpf_iter_fini_udp(void *priv_data)
> {
> - struct udp_iter_state *st = priv_data;
> -
> - kfree(st->bpf_seq_afinfo);
> bpf_iter_fini_seq_net(priv_data);
> }
>
> --
> 2.34.1
>
