diff options
| author | KP Singh <kpsingh@google.com> | 2020-03-04 20:18:47 +0100 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-03-04 13:41:05 -0800 |
| commit | 88fd9e5352fe05f7fe57778293aebd4cd106960b (patch) | |
| tree | a8bc1ce304a0f7e5594666995fe5d3863dbda3e5 /include | |
| parent | cc6fa771024ffdb428bdf25a94309cf21e8ef1b9 (diff) | |
bpf: Refactor trampoline update code
As we need to introduce a third type of attachment for trampolines, the
flattened signature of arch_prepare_bpf_trampoline gets even more
complicated.
Refactor the prog and count argument to arch_prepare_bpf_trampoline to
use bpf_tramp_progs to simplify the addition and accounting for new
attachment types.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200304191853.1529-2-kpsingh@chromium.org
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/bpf.h | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index f13c78c6f29d..98ec10b23dbb 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -433,6 +433,16 @@ struct btf_func_model { */ #define BPF_TRAMP_F_SKIP_FRAME BIT(2) +/* Each call __bpf_prog_enter + call bpf_func + call __bpf_prog_exit is ~50 + * bytes on x86. Pick a number to fit into BPF_IMAGE_SIZE / 2 + */ +#define BPF_MAX_TRAMP_PROGS 40 + +struct bpf_tramp_progs { + struct bpf_prog *progs[BPF_MAX_TRAMP_PROGS]; + int nr_progs; +}; + /* Different use cases for BPF trampoline: * 1. replace nop at the function entry (kprobe equivalent) * flags = BPF_TRAMP_F_RESTORE_REGS @@ -455,8 +465,7 @@ struct btf_func_model { */ int arch_prepare_bpf_trampoline(void *image, void *image_end, const struct btf_func_model *m, u32 flags, - struct bpf_prog **fentry_progs, int fentry_cnt, - struct bpf_prog **fexit_progs, int fexit_cnt, + struct bpf_tramp_progs *tprogs, void *orig_call); /* these two functions are called from generated trampoline */ u64 notrace __bpf_prog_enter(void); |