bpf: Add support for kfunc set with common btf_ids

Later on, we will introduce kfuncs bpf_cast_to_kern_ctx() and
bpf_rdonly_cast() which apply to all program types. Currently kfunc set
only supports individual prog types. This patch added support for kfunc
applying to all program types.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221120195426.3113828-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Yonghong Song 2022-11-20 11:54:26 -08:00 committed by Alexei Starovoitov
parent e181d3f143
commit cfe1456440
2 changed files with 19 additions and 1 deletions

View file

@ -199,6 +199,7 @@ DEFINE_IDR(btf_idr);
DEFINE_SPINLOCK(btf_idr_lock);
enum btf_kfunc_hook {
BTF_KFUNC_HOOK_COMMON,
BTF_KFUNC_HOOK_XDP,
BTF_KFUNC_HOOK_TC,
BTF_KFUNC_HOOK_STRUCT_OPS,
@ -7531,6 +7532,8 @@ static u32 *__btf_kfunc_id_set_contains(const struct btf *btf,
static int bpf_prog_type_to_kfunc_hook(enum bpf_prog_type prog_type)
{
switch (prog_type) {
case BPF_PROG_TYPE_UNSPEC:
return BTF_KFUNC_HOOK_COMMON;
case BPF_PROG_TYPE_XDP:
return BTF_KFUNC_HOOK_XDP;
case BPF_PROG_TYPE_SCHED_CLS:
@ -7559,6 +7562,11 @@ u32 *btf_kfunc_id_set_contains(const struct btf *btf,
u32 kfunc_btf_id)
{
enum btf_kfunc_hook hook;
u32 *kfunc_flags;
kfunc_flags = __btf_kfunc_id_set_contains(btf, BTF_KFUNC_HOOK_COMMON, kfunc_btf_id);
if (kfunc_flags)
return kfunc_flags;
hook = bpf_prog_type_to_kfunc_hook(prog_type);
return __btf_kfunc_id_set_contains(btf, hook, kfunc_btf_id);

View file

@ -1901,10 +1901,19 @@ static const struct btf_kfunc_id_set generic_kfunc_set = {
.set = &generic_btf_ids,
};
BTF_ID_LIST(generic_dtor_ids)
BTF_ID(struct, task_struct)
BTF_ID(func, bpf_task_release)
BTF_SET8_START(common_btf_ids)
BTF_SET8_END(common_btf_ids)
static const struct btf_kfunc_id_set common_kfunc_set = {
.owner = THIS_MODULE,
.set = &common_btf_ids,
};
static int __init kfunc_init(void)
{
int ret;
@ -1918,9 +1927,10 @@ static int __init kfunc_init(void)
ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &generic_kfunc_set);
ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &generic_kfunc_set);
ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS, &generic_kfunc_set);
return ret ?: register_btf_id_dtor_kfuncs(generic_dtors,
ret = ret ?: register_btf_id_dtor_kfuncs(generic_dtors,
ARRAY_SIZE(generic_dtors),
THIS_MODULE);
return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_UNSPEC, &common_kfunc_set);
}
late_initcall(kfunc_init);