selftests/bpf: verifier/xdp.c converted to inline assembly

Test verifier/xdp.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

Author: eddyz87

tools/testing/selftests/bpf/prog_tests/verifier.c

@@ -39,6 +39,7 @@
 #include "verifier_value_or_null.skel.h"
 #include "verifier_var_off.skel.h"
 #include "verifier_xadd.skel.h"
+#include "verifier_xdp.skel.h"
 
 __maybe_unused
 static void run_tests_aux(const char *skel_name, skel_elf_bytes_fn elf_bytes_factory)
@@ -100,3 +101,4 @@ void test_verifier_value(void)                { RUN(verifier_value); }
 void test_verifier_value_or_null(void)        { RUN(verifier_value_or_null); }
 void test_verifier_var_off(void)              { RUN(verifier_var_off); }
 void test_verifier_xadd(void)                 { RUN(verifier_xadd); }
+void test_verifier_xdp(void)                  { RUN(verifier_xdp); }

tools/testing/selftests/bpf/progs/verifier_xdp.c

@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Converted from tools/testing/selftests/bpf/verifier/xdp.c */
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+SEC("xdp")
+__description("XDP, using ifindex from netdev")
+__success __retval(1)
+__naked void xdp_using_ifindex_from_netdev(void)
+{
+	asm volatile ("					\
+	r0 = 0;						\
+	r2 = *(u32*)(r1 + %[xdp_md_ingress_ifindex]);	\
+	if r2 < 1 goto l0_%=;				\
+	r0 = 1;						\
+l0_%=:	exit;						\
+"	:
+	: __imm_const(xdp_md_ingress_ifindex, offsetof(struct xdp_md, ingress_ifindex))
+	: __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";