bpf: pass original insn directly to convert_ctx_access

Currently, when calling convert_ctx_access() callback for the various
program types, we pass in insn->dst_reg, insn->src_reg, insn->off from
the original instruction. This information is needed to rewrite the
instruction that is based on the user ctx structure into a kernel
representation for the ctx. As we'd like to allow access size beyond
just BPF_W, we'd need also insn->code for that in order to decode the
original access size. Given that, lets just pass insn directly to the
convert_ctx_access() callback and work on that to not clutter the
callback with even more arguments we need to pass when everything is
already contained in insn. So lets go through that once, no functional
change.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 94ea8d2..f8c3560 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -161,9 +161,10 @@
 				enum bpf_reg_type *reg_type);
 	int (*gen_prologue)(struct bpf_insn *insn, bool direct_write,
 			    const struct bpf_prog *prog);
-	u32 (*convert_ctx_access)(enum bpf_access_type type, int dst_reg,
-				  int src_reg, int ctx_off,
-				  struct bpf_insn *insn, struct bpf_prog *prog);
+	u32 (*convert_ctx_access)(enum bpf_access_type type,
+				  const struct bpf_insn *src,
+				  struct bpf_insn *dst,
+				  struct bpf_prog *prog);
 };
 
 struct bpf_prog_type_list {