From fbb0de795078190a9834b3409e4b009cfb18a6d4 Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Mon, 27 Aug 2018 11:34:44 +0200
Subject: Add udmabuf misc device

A driver to let userspace turn memfd regions into dma-bufs.

Use case:  Allows qemu create dmabufs for the vga framebuffer or
virtio-gpu ressources.  Then they can be passed around to display
those guest things on the host.  To spice client for classic full
framebuffer display, and hopefully some day to wayland server for
seamless guest window display.

qemu test branch:
  https://git.kraxel.org/cgit/qemu/log/?h=sirius/udmabuf

Cc: David Airlie <airlied@linux.ie>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20180827093444.23623-1-kraxel@redhat.com
---
 tools/testing/selftests/drivers/dma-buf/Makefile  |  5 ++
 tools/testing/selftests/drivers/dma-buf/udmabuf.c | 96 +++++++++++++++++++++++
 2 files changed, 101 insertions(+)
 create mode 100644 tools/testing/selftests/drivers/dma-buf/Makefile
 create mode 100644 tools/testing/selftests/drivers/dma-buf/udmabuf.c

(limited to 'tools/testing/selftests/drivers')

diff --git a/tools/testing/selftests/drivers/dma-buf/Makefile b/tools/testing/selftests/drivers/dma-buf/Makefile
new file mode 100644
index 000000000000..4154c3d7aa58
--- /dev/null
+++ b/tools/testing/selftests/drivers/dma-buf/Makefile
@@ -0,0 +1,5 @@
+CFLAGS += -I../../../../../usr/include/
+
+TEST_GEN_PROGS := udmabuf
+
+include ../../lib.mk
diff --git a/tools/testing/selftests/drivers/dma-buf/udmabuf.c b/tools/testing/selftests/drivers/dma-buf/udmabuf.c
new file mode 100644
index 000000000000..376b1d6730bd
--- /dev/null
+++ b/tools/testing/selftests/drivers/dma-buf/udmabuf.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <malloc.h>
+
+#include <sys/ioctl.h>
+#include <sys/syscall.h>
+#include <linux/memfd.h>
+#include <linux/udmabuf.h>
+
+#define TEST_PREFIX	"drivers/dma-buf/udmabuf"
+#define NUM_PAGES       4
+
+static int memfd_create(const char *name, unsigned int flags)
+{
+	return syscall(__NR_memfd_create, name, flags);
+}
+
+int main(int argc, char *argv[])
+{
+	struct udmabuf_create create;
+	int devfd, memfd, buf, ret;
+	off_t size;
+	void *mem;
+
+	devfd = open("/dev/udmabuf", O_RDWR);
+	if (devfd < 0) {
+		printf("%s: [skip,no-udmabuf]\n", TEST_PREFIX);
+		exit(77);
+	}
+
+	memfd = memfd_create("udmabuf-test", MFD_CLOEXEC);
+	if (memfd < 0) {
+		printf("%s: [skip,no-memfd]\n", TEST_PREFIX);
+		exit(77);
+	}
+
+	size = getpagesize() * NUM_PAGES;
+	ret = ftruncate(memfd, size);
+	if (ret == -1) {
+		printf("%s: [FAIL,memfd-truncate]\n", TEST_PREFIX);
+		exit(1);
+	}
+
+	memset(&create, 0, sizeof(create));
+
+	/* should fail (offset not page aligned) */
+	create.memfd  = memfd;
+	create.offset = getpagesize()/2;
+	create.size   = getpagesize();
+	buf = ioctl(devfd, UDMABUF_CREATE, &create);
+	if (buf >= 0) {
+		printf("%s: [FAIL,test-1]\n", TEST_PREFIX);
+		exit(1);
+	}
+
+	/* should fail (size not multiple of page) */
+	create.memfd  = memfd;
+	create.offset = 0;
+	create.size   = getpagesize()/2;
+	buf = ioctl(devfd, UDMABUF_CREATE, &create);
+	if (buf >= 0) {
+		printf("%s: [FAIL,test-2]\n", TEST_PREFIX);
+		exit(1);
+	}
+
+	/* should fail (not memfd) */
+	create.memfd  = 0; /* stdin */
+	create.offset = 0;
+	create.size   = size;
+	buf = ioctl(devfd, UDMABUF_CREATE, &create);
+	if (buf >= 0) {
+		printf("%s: [FAIL,test-3]\n", TEST_PREFIX);
+		exit(1);
+	}
+
+	/* should work */
+	create.memfd  = memfd;
+	create.offset = 0;
+	create.size   = size;
+	buf = ioctl(devfd, UDMABUF_CREATE, &create);
+	if (buf < 0) {
+		printf("%s: [FAIL,test-4]\n", TEST_PREFIX);
+		exit(1);
+	}
+
+	fprintf(stderr, "%s: ok\n", TEST_PREFIX);
+	close(buf);
+	close(memfd);
+	close(devfd);
+	return 0;
+}
-- 
cgit v1.2.3-59-g8ed1b