[PATCH v2 char-misc-next 7/7] samples: mic: Add sample VOP userspace

[Vincent Whitchurch <vincent.whitchurch@axis.com>]

Add a sample userspace program which can be used with the VOP framework
with vop-loopback and non-MIC hardware.

For example, the following commands can be used to test networking over
vop-loopback.  (IPv6 is used with zone indices to force traffic through
the interfaces instead of short-circuit delivery, since both interfaces
are on the same system.)

 # modprobe vop_loopback
 # ./vopd &

 Setup host interface:
 # ip a a dev mic0 scope link fe80::0
 # ip link set dev mic0 up

 Setup guest interface:
 # ip a a dev eth1 scope link fe80::1
 # ip link set dev eth1 up

 Ping from host to guest:
 # ping6 fe80::1%mic0

 Ping from guest to host:
 # ping6 fe80::0%eth1

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
---
 samples/mic/mpssd/.gitignore |  1 +
 samples/mic/mpssd/Makefile   |  5 ++++-
 samples/mic/mpssd/vopd.c     | 25 +++++++++++++++++++++++++
 3 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 samples/mic/mpssd/vopd.c

diff --git a/samples/mic/mpssd/.gitignore b/samples/mic/mpssd/.gitignore
index 8b7c72f07c92..34c001135abb 100644
--- a/samples/mic/mpssd/.gitignore
+++ b/samples/mic/mpssd/.gitignore
@@ -1 +1,2 @@
 mpssd
+vopd
diff --git a/samples/mic/mpssd/Makefile b/samples/mic/mpssd/Makefile
index bc94054dbe2b..b94b18de5a43 100644
--- a/samples/mic/mpssd/Makefile
+++ b/samples/mic/mpssd/Makefile
@@ -5,7 +5,7 @@ ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
 
 ifeq ($(ARCH),x86)
 
-PROGS := mpssd
+PROGS := mpssd vopd
 CC = $(CROSS_COMPILE)gcc
 CFLAGS := -I../../../usr/include -I../../../tools/include
 
@@ -17,6 +17,9 @@ all: $(PROGS)
 mpssd: mpssd.c sysfs.c vop.o
 	$(CC) $(CFLAGS) $^ -o $@ -lpthread
 
+vopd: vopd.c vop.o
+	$(CC) $(CFLAGS) $^ -o $@ -lpthread
+
 install:
 	install mpssd /usr/sbin/mpssd
 	install micctrl /usr/sbin/micctrl
diff --git a/samples/mic/mpssd/vopd.c b/samples/mic/mpssd/vopd.c
new file mode 100644
index 000000000000..48c1877fed28
--- /dev/null
+++ b/samples/mic/mpssd/vopd.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <stdio.h>
+
+#include "mpssd.h"
+
+void mpsslog(char *format, ...)
+{
+	va_list args;
+
+	va_start(args, format);
+	vprintf(format, args);
+	va_end(args);
+}
+
+int main(int argc, char *argv[])
+{
+	struct mic_info themic = {
+		.name = "mic",
+	};
+
+	serve_virtio(&themic, &themic);
+
+	return 0;
+}
-- 
2.20.0