lib/sw_sync: Add helper functions for managing synchronization primitives

Base functions to help testing the Sync File Framework (explicit fencing
mechanism ported from Android).
These functions allow you to create, use and destroy timelines and fences.

Signed-off-by: Robert Foss <robert.foss@collabora.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Eric Engestrom <eric@engestrom.ch>
Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>

1 files changed, 214 insertions, 0 deletions

diff --git a/lib/sw_sync.c b/lib/sw_sync.c
new file mode 100644
index 00000000..aa8feefe
--- /dev/null
+++ b/lib/sw_sync.c
@@ -0,0 +1,214 @@
+/*
+ * Copyright © 2016 Collabora, Ltd.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * Authors:
+ *    Robert Foss <robert.foss@collabora.com>
+ */
+
+#ifndef ANDROID
+#define _GNU_SOURCE
+#else
+#include <libgen.h>
+#endif
+#include <fcntl.h>
+#include <poll.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <linux/sync_file.h>
+#include <sys/ioctl.h>
+
+#include "igt_debugfs.h"
+#include "sw_sync.h"
+#include "drmtest.h"
+#include "ioctl_wrappers.h"
+
+#ifndef SW_SYNC_IOC_INC
+struct sw_sync_create_fence_data {
+	__u32	value;
+	char	name[32];
+	__s32	fence;
+};
+
+#define LOCAL_SW_SYNC_IOC_MAGIC		    'W'
+#define LOCAL_SW_SYNC_IOC_CREATE_FENCE	_IOWR(LOCAL_SW_SYNC_IOC_MAGIC, 0,\
+						                        struct sw_sync_create_fence_data)
+#define LOCAL_SW_SYNC_IOC_INC			_IOW(LOCAL_SW_SYNC_IOC_MAGIC, 1, __u32)
+#endif
+
+
+static bool kernel_sw_sync_path(char *path, int length)
+{
+	snprintf(path, length, "%s", "/dev/sw_sync");
+	if (access(path, R_OK | W_OK) == 0) {
+	    return true;
+	}
+
+	snprintf(path, length, "%s", "/sys/kernel/debug/sync/sw_sync");
+	if (access(path, R_OK | W_OK) == 0) {
+	    return true;
+	}
+
+	snprintf(path, length, "%s/sw_sync", igt_debugfs_mount());
+	if (access(path, R_OK | W_OK) == 0) {
+	    return true;
+	}
+
+    return false;
+}
+
+static bool sw_sync_fd_is_valid(int fd)
+{
+	int status;
+
+	if (fd < 0)
+		return 0;
+
+	status = fcntl(fd, F_GETFD, 0);
+	return status >= 0;
+}
+
+int sw_sync_timeline_create(void)
+{
+	char buf[128];
+	int fd;
+
+	igt_assert_f(kernel_sw_sync_path(buf, sizeof(buf)),
+	    "Unable to find valid path for sw_sync\n");
+
+	fd = open(buf, O_RDWR);
+	igt_assert_f(sw_sync_fd_is_valid(fd), "Created invalid timeline\n");
+
+	return fd;
+}
+
+int __sw_sync_fence_create(int fd, uint32_t seqno)
+{
+	struct sw_sync_create_fence_data data = {0};
+	data.value = seqno;
+
+	if (igt_ioctl(fd, LOCAL_SW_SYNC_IOC_CREATE_FENCE, &data))
+		return -errno;
+
+	return data.fence;
+}
+
+int sw_sync_fence_create(int fd, uint32_t seqno)
+{
+	int fence = __sw_sync_fence_create(fd, seqno);
+
+	igt_assert_f(sw_sync_fd_is_valid(fence), "Created invalid fence\n");
+
+	return fence;
+}
+
+void sw_sync_timeline_inc(int fd, uint32_t count)
+{
+	uint32_t arg = count;
+
+	do_ioctl(fd, LOCAL_SW_SYNC_IOC_INC, &arg);
+}
+
+int sync_merge(int fd1, int fd2)
+{
+	struct sync_merge_data data = {};
+	int err;
+
+	data.fd2 = fd2;
+
+	err = ioctl(fd1, SYNC_IOC_MERGE, &data);
+	if (err < 0)
+		return -errno;
+
+	return data.fence;
+}
+
+int sync_wait(int fd, int timeout)
+{
+	struct pollfd fds = {0};
+	int ret;
+
+	fds.fd = fd;
+	fds.events = POLLIN;
+
+	do {
+		 ret = poll(&fds, 1, timeout);
+		 if (ret > 0) {
+			  if (fds.revents & (POLLERR | POLLNVAL)) {
+				   errno = EINVAL;
+				   return -1;
+			  }
+			  return 0;
+		 } else if (ret == 0) {
+			  errno = ETIME;
+			  return -1;
+		 }
+	} while (ret == -1 && (errno == EINTR || errno == EAGAIN));
+
+	return ret;
+}
+
+int sync_fence_count(int fd)
+{
+	struct sync_file_info info = {0};
+
+	if (ioctl(fd, SYNC_IOC_FILE_INFO, &info))
+		return -errno;
+
+	return info.num_fences;
+}
+
+static int __sync_fence_count_status(int fd, int status)
+{
+	struct sync_file_info info = {0};
+	struct sync_fence_info *fence_info;
+	int count;
+	int i;
+
+	if (ioctl(fd, SYNC_IOC_FILE_INFO, &info))
+		return -errno;
+
+	fence_info = calloc(info.num_fences, sizeof(*fence_info));
+	if (!fence_info)
+		return -ENOMEM;
+
+	info.sync_fence_info = (uintptr_t)fence_info;
+	if (ioctl(fd, SYNC_IOC_FILE_INFO, &info)) {
+		count = -errno;
+	} else {
+		count = 0;
+		for (i = 0 ; i < info.num_fences ; i++)
+			if (fence_info[i].status == status)
+				count++;
+	}
+
+	free(fence_info);
+
+	return count;
+}
+
+int sync_fence_count_status(int fd, int status)
+{
+	int count = __sync_fence_count_status(fd, status);
+	igt_assert_f(count >= 0, "No fences with supplied status found\n");
+
+	return count;
+}