diff options
| author | Amery Hung <amery.hung@bytedance.com> | 2025-02-17 11:06:37 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-02-17 18:47:27 -0800 |
| commit | a687df2008f66669deec27f74d1793c8a537a4bd (patch) | |
| tree | e9f39a9635fe5166a01ee1b6b825514f294f353b /include | |
| parent | 432051806f614ca512da401b80257b95b2a2241e (diff) | |
bpf: Support getting referenced kptr from struct_ops argument
Allows struct_ops programs to acqurie referenced kptrs from arguments
by directly reading the argument.
The verifier will acquire a reference for struct_ops a argument tagged
with "__ref" in the stub function in the beginning of the main program.
The user will be able to access the referenced kptr directly by reading
the context as long as it has not been released by the program.
This new mechanism to acquire referenced kptr (compared to the existing
"kfunc with KF_ACQUIRE") is introduced for ergonomic and semantic reasons.
In the first use case, Qdisc_ops, an skb is passed to .enqueue in the
first argument. This mechanism provides a natural way for users to get a
referenced kptr in the .enqueue struct_ops programs and makes sure that a
qdisc will always enqueue or drop the skb.
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20250217190640.1748177-3-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/bpf.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index f4df39e8c735..15164787ce7f 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -968,6 +968,7 @@ struct bpf_insn_access_aux { struct { struct btf *btf; u32 btf_id; + u32 ref_obj_id; }; }; struct bpf_verifier_log *log; /* for verbose logs */ @@ -1481,6 +1482,8 @@ struct bpf_ctx_arg_aux { enum bpf_reg_type reg_type; struct btf *btf; u32 btf_id; + u32 ref_obj_id; + bool refcounted; }; struct btf_mod_pair { |