[RFC bpf-next v4 4/6] bpf: add btf pointer to struct bpf_ctx_arg_aux.

[thinker.li@xxxxxxxxx]

From: Kui-Feng Lee <thinker.li@xxxxxxxxx>

Enable the providers to use types defined in a module instead of in the
kernel (btf_vmlinux).

Signed-off-by: Kui-Feng Lee <thinker.li@xxxxxxxxx>
---
 include/linux/bpf.h | 1 +
 kernel/bpf/btf.c    | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 1ebbee1d648e..9a2ee9456989 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1416,6 +1416,7 @@ struct bpf_ctx_arg_aux {
 	u32 offset;
 	enum bpf_reg_type reg_type;
 	u32 btf_id;
+	struct btf *btf;
 };
 
 struct btf_mod_pair {
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index d3f94d04c69d..20d2160b3db5 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -6263,7 +6263,7 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type,
 			}
 
 			info->reg_type = ctx_arg_info->reg_type;
-			info->btf = btf_vmlinux;
+			info->btf = ctx_arg_info->btf ? ctx_arg_info->btf : btf_vmlinux;
 			info->btf_id = ctx_arg_info->btf_id;
 			return true;
 		}
-- 
2.34.1