2 files changed, 85 insertions, 0 deletions

diff --git a/tools/testing/vsock/util.c b/tools/testing/vsock/util.c
index b7b3fb2221c1..803f1e075b62 100644
--- a/tools/testing/vsock/util.c
+++ b/tools/testing/vsock/util.c
@@ -7,6 +7,7 @@
  * Author: Stefan Hajnoczi <stefanha@redhat.com>
  */
 
+#include <ctype.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdint.h>
@@ -23,6 +24,9 @@
 #include "control.h"
 #include "util.h"
 
+#define KALLSYMS_PATH		"/proc/kallsyms"
+#define KALLSYMS_LINE_LEN	512
+
 /* Install signal handlers */
 void init_signals(void)
 {
@@ -854,3 +858,55 @@ void enable_so_linger(int fd, int timeout)
 		exit(EXIT_FAILURE);
 	}
 }
+
+static int __get_transports(void)
+{
+	char buf[KALLSYMS_LINE_LEN];
+	const char *ksym;
+	int ret = 0;
+	FILE *f;
+
+	f = fopen(KALLSYMS_PATH, "r");
+	if (!f) {
+		perror("Can't open " KALLSYMS_PATH);
+		exit(EXIT_FAILURE);
+	}
+
+	while (fgets(buf, sizeof(buf), f)) {
+		char *match;
+		int i;
+
+		assert(buf[strlen(buf) - 1] == '\n');
+
+		for (i = 0; i < TRANSPORT_NUM; ++i) {
+			if (ret & BIT(i))
+				continue;
+
+			/* Match should be followed by '\t' or '\n'.
+			 * See kallsyms.c:s_show().
+			 */
+			ksym = transport_ksyms[i];
+			match = strstr(buf, ksym);
+			if (match && isspace(match[strlen(ksym)])) {
+				ret |= BIT(i);
+				break;
+			}
+		}
+	}
+
+	fclose(f);
+	return ret;
+}
+
+/* Return integer with TRANSPORT_* bit set for every (known) registered vsock
+ * transport.
+ */
+int get_transports(void)
+{
+	static int tr = -1;
+
+	if (tr == -1)
+		tr = __get_transports();
+
+	return tr;
+}
diff --git a/tools/testing/vsock/util.h b/tools/testing/vsock/util.h
index 0afe7cbae12e..71895192cc02 100644
--- a/tools/testing/vsock/util.h
+++ b/tools/testing/vsock/util.h
@@ -3,8 +3,36 @@
 #define UTIL_H
 
 #include <sys/socket.h>
+#include <linux/bitops.h>
+#include <linux/kernel.h>
 #include <linux/vm_sockets.h>
 
+/* All known vsock transports, see callers of vsock_core_register() */
+#define KNOWN_TRANSPORTS(x)		\
+	x(LOOPBACK, "loopback")		\
+	x(VIRTIO, "virtio")		\
+	x(VHOST, "vhost")		\
+	x(VMCI, "vmci")			\
+	x(HYPERV, "hvs")
+
+enum transport {
+	TRANSPORT_COUNTER_BASE = __COUNTER__ + 1,
+	#define x(name, symbol)		\
+		TRANSPORT_##name = BIT(__COUNTER__ - TRANSPORT_COUNTER_BASE),
+	KNOWN_TRANSPORTS(x)
+	TRANSPORT_NUM = __COUNTER__ - TRANSPORT_COUNTER_BASE,
+	#undef x
+};
+
+static const char * const transport_ksyms[] = {
+	#define x(name, symbol) "d " symbol "_transport",
+	KNOWN_TRANSPORTS(x)
+	#undef x
+};
+
+static_assert(ARRAY_SIZE(transport_ksyms) == TRANSPORT_NUM);
+static_assert(BITS_PER_TYPE(int) >= TRANSPORT_NUM);
+
 /* Tests can either run as the client or the server */
 enum test_mode {
 	TEST_MODE_UNSET,
@@ -82,4 +110,5 @@ void setsockopt_timeval_check(int fd, int level, int optname,
 			      struct timeval val, char const *errmsg);
 void enable_so_zerocopy_check(int fd);
 void enable_so_linger(int fd, int timeout);
+int get_transports(void);
 #endif /* UTIL_H */