[PATCH bpf-next v7 1/6] bpf: export necessary sympols for modules with struct_ops

["D. Wythe" <alibuda@linux.alibaba.com>]

Exports three necessary symbols for implementing struct_ops with
tristate subsystem.

To hold or release refcnt of struct_ops refcnt by inline funcs
bpf_try_module_get and bpf_module_put which use bpf_struct_ops_get(put)
conditionally.

And to copy obj name from one to the other with effective checks by
bpf_obj_name_cpy.

Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
---
 kernel/bpf/bpf_struct_ops.c | 2 ++
 kernel/bpf/syscall.c        | 1 +
 2 files changed, 3 insertions(+)

diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
index 040fb1cd840b..588e9b43fc2a 100644
--- a/kernel/bpf/bpf_struct_ops.c
+++ b/kernel/bpf/bpf_struct_ops.c
@@ -1140,6 +1140,7 @@ bool bpf_struct_ops_get(const void *kdata)
 	map = __bpf_map_inc_not_zero(&st_map->map, false);
 	return !IS_ERR(map);
 }
+EXPORT_SYMBOL_GPL(bpf_struct_ops_get);
 
 void bpf_struct_ops_put(const void *kdata)
 {
@@ -1151,6 +1152,7 @@ void bpf_struct_ops_put(const void *kdata)
 
 	bpf_map_put(&st_map->map);
 }
+EXPORT_SYMBOL_GPL(bpf_struct_ops_put);
 
 int bpf_struct_ops_supported(const struct bpf_struct_ops *st_ops, u32 moff)
 {
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 0daf098e3207..85bee712b16c 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1171,6 +1171,7 @@ int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
 
 	return src - orig_src;
 }
+EXPORT_SYMBOL_GPL(bpf_obj_name_cpy);
 
 int map_check_no_btf(const struct bpf_map *map,
 		     const struct btf *btf,
-- 
2.45.0