On 12/13/24 3:29 PM, Amery Hung wrote:
+static int bpf_qdisc_init_member(const struct btf_type *t,
+ const struct btf_member *member,
+ void *kdata, const void *udata)
+{
+ const struct Qdisc_ops *uqdisc_ops;
+ struct Qdisc_ops *qdisc_ops;
+ u32 moff;
+
+ uqdisc_ops = (const struct Qdisc_ops *)udata;
+ qdisc_ops = (struct Qdisc_ops *)kdata;
+
+ moff = __btf_member_bit_offset(t, member) / 8;
+ switch (moff) {
+ case offsetof(struct Qdisc_ops, priv_size):
+ if (uqdisc_ops->priv_size)
bpf_struct_ops_map_update_elem() has enforced non function pointer member must
be zero if ->init_member() returns 0, so this check is unnecessary.
+ return -EINVAL;
+ return 1;
+ case offsetof(struct Qdisc_ops, static_flags):
+ if (uqdisc_ops->static_flags)
Same here.
case priv_size and static_flags should be not needed, just return 0.
+ return -EINVAL;
+ return 1;
+ case offsetof(struct Qdisc_ops, peek):
+ if (!uqdisc_ops->peek)
bpf_struct_ops_map_update_elem() will assign the trampoline (that will call the
bpf prog) to qdisc_ops->peek if the "u"qdisc_ops->peek has the prog fd.
This test is not necessary also.
+ qdisc_ops->peek = qdisc_peek_dequeued;
Always do this assignment
+ return 1;
and return 0 here. Allow the bpf_struct_ops_map_update_elem() to do the needed
fd testing instead and reassign the qdisc_ops->peek with the trampoline if needed.
+ case offsetof(struct Qdisc_ops, id):
+ if (bpf_obj_name_cpy(qdisc_ops->id, uqdisc_ops->id,
+ sizeof(qdisc_ops->id)) <= 0)
+ return -EINVAL;
+ return 1;
+ }
+
+ return 0;
+}
