filter: bpf_jit_comp: refactor and unify BPF JIT image dump output

If bpf_jit_enable > 1, then we dump the emitted JIT compiled image
after creation. Currently, only SPARC and PowerPC has similar output
as in the reference implementation on x86_64. Make a small helper
function in order to reduce duplicated code and make the dump output
uniform across architectures x86_64, SPARC, PPC, ARM (e.g. on ARM
flen, pass and proglen are currently not shown, but would be
interesting to know as well), also for future BPF JIT implementations
on other archs.

Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Eric Dumazet <eric.dumazet@google.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/filter.h b/include/linux/filter.h
index d2059cb..d7d2508 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -50,6 +50,16 @@
 #ifdef CONFIG_BPF_JIT
 extern void bpf_jit_compile(struct sk_filter *fp);
 extern void bpf_jit_free(struct sk_filter *fp);
+
+static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
+				u32 pass, void *image)
+{
+	pr_err("flen=%u proglen=%u pass=%u image=%p\n",
+	       flen, proglen, pass, image);
+	if (image)
+		print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_ADDRESS,
+			       16, 1, image, proglen, false);
+}
 #define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns)
 #else
 static inline void bpf_jit_compile(struct sk_filter *fp)