On Mon, Apr 29, 2024 at 2:36 PM Kui-Feng Lee <thinker.li@xxxxxxxxx> wrote:
>
> Add epoll support to bpf struct_ops links to trigger EPOLLHUP event upon
> detachment.
>
> Signed-off-by: Kui-Feng Lee <thinker.li@xxxxxxxxx>
> ---
> include/linux/bpf.h | 2 ++
> kernel/bpf/bpf_struct_ops.c | 14 ++++++++++++++
> kernel/bpf/syscall.c | 15 +++++++++++++++
> 3 files changed, 31 insertions(+)
>
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index eeeed4b1bd32..a4550b927352 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
> @@ -1574,6 +1574,7 @@ struct bpf_link {
> const struct bpf_link_ops *ops;
> struct bpf_prog *prog;
> struct work_struct work;
> + wait_queue_head_t wait_hup;
let's keep it struct_ops-specific, there is no need to pay for this
for all existing BPF link types. We can always generalize later, if
necessary.
pw-bot: cr
> };
>
> struct bpf_link_ops {
> @@ -1587,6 +1588,7 @@ struct bpf_link_ops {
> struct bpf_link_info *info);
> int (*update_map)(struct bpf_link *link, struct bpf_map *new_map,
> struct bpf_map *old_map);
> + __poll_t (*poll)(struct file *file, struct poll_table_struct *pts);
> };
>
> struct bpf_tramp_link {
[...]
