Re: [PATCH bpf-next v16 11/14] bpf, net: switch to dynamic registration

[Kui-Feng Lee <sinquersw@gmail.com>]

On 1/18/24 14:25, Martin KaFai Lau wrote:
> On 1/17/24 5:49 PM, thinker.li@gmail.com wrote:
>> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
>> index 1cfbb89944c5..a2522fcfe57c 100644
>> --- a/include/linux/bpf.h
>> +++ b/include/linux/bpf.h
>> @@ -1700,10 +1700,22 @@ struct bpf_struct_ops_common_value {
>>       enum bpf_struct_ops_state state;
>>   };
>> +/* This macro helps developer to register a struct_ops type and generate
>> + * type information correctly. Developers should use this macro to 
>> register
>> + * a struct_ops type instead of calling register_bpf_struct_ops() 
>> directly.
>> + */
>> +#define REGISTER_BPF_STRUCT_OPS(st_ops, type)                \
> 
> One final nit on this macro. Rename this to register_bpf_struct_ops 
> since it is the one will be used a lot, so give it an easier typing name.
> 
>> +    ({                                \
>> +        struct bpf_struct_ops_##type {                \
>> +            struct bpf_struct_ops_common_value common;    \
>> +            struct type data ____cacheline_aligned_in_smp;    \
>> +        };                            \
>> +        BTF_TYPE_EMIT(struct bpf_struct_ops_##type);        \
>> +        register_bpf_struct_ops(st_ops);            \
> 
> and rename this to __register_bpf_struct_ops. Thanks.

Sure!

> 
>> +    })
>> +
>>   #if defined(CONFIG_BPF_JIT) && defined(CONFIG_BPF_SYSCALL)
>>   #define BPF_MODULE_OWNER ((void *)((0xeB9FUL << 2) + 
>> POISON_POINTER_DELTA))
>> -const struct bpf_struct_ops_desc *bpf_struct_ops_find(struct btf 
>> *btf, u32 type_id);
>> -void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log);
>>   bool bpf_struct_ops_get(const void *kdata);
>>   void bpf_struct_ops_put(const void *kdata);
>>   int bpf_struct_ops_map_sys_lookup_elem(struct bpf_map *map, void *key,
>> @@ -1745,16 +1757,11 @@ struct bpf_dummy_ops {
>>   int bpf_struct_ops_test_run(struct bpf_prog *prog, const union 
>> bpf_attr *kattr,
>>                   union bpf_attr __user *uattr);
>>   #endif
>> +int bpf_struct_ops_desc_init(struct bpf_struct_ops_desc *st_ops_desc,
>> +                 struct btf *btf,
>> +                 struct bpf_verifier_log *log);
>>   void bpf_map_struct_ops_info_fill(struct bpf_map_info *info, struct 
>> bpf_map *map);
>>   #else
>> -static inline const struct bpf_struct_ops_desc 
>> *bpf_struct_ops_find(struct btf *btf, u32 type_id)
>> -{
>> -    return NULL;
>> -}
>> -static inline void bpf_struct_ops_init(struct btf *btf,
>> -                       struct bpf_verifier_log *log)
>> -{
>> -}
>>   static inline bool bpf_try_module_get(const void *data, struct 
>> module *owner)
>>   {
>>       return try_module_get(owner);
>> @@ -1769,6 +1776,10 @@ static inline int 
>> bpf_struct_ops_map_sys_lookup_elem(struct bpf_map *map,
>>   {
>>       return -EINVAL;
>>   }
>> +static inline int bpf_struct_ops_link_create(union bpf_attr *attr)
>> +{
>> +    return -EOPNOTSUPP;
>> +}
> 
> This is added back here which was removed in patch 3...
> 
> Others lgtm.
>