/*
 *
 * (C) COPYRIGHT 2012-2016 ARM Limited. All rights reserved.
 *
 * This program is free software and is provided to you under the terms of the
 * GNU General Public License version 2 as published by the Free Software
 * Foundation, and any use by you of this program is subject to the terms
 * of such GNU licence.
 *
 * A copy of the licence is included with the program, and can also be obtained
 * from Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA  02110-1301, USA.
 *
 */


/**
 * @file mali_kbase_sync_user.c
 *
 */

#ifdef CONFIG_SYNC

#include <linux/sched.h>
#include <linux/fdtable.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/anon_inodes.h>
#include <linux/version.h>
#include <linux/uaccess.h>
#include <mali_kbase_sync.h>

static int kbase_stream_close(struct inode *inode, struct file *file)
{
	struct sync_timeline *tl;

	tl = (struct sync_timeline *)file->private_data;
	BUG_ON(!tl);
	sync_timeline_destroy(tl);
	return 0;
}

static const struct file_operations stream_fops = {
	.owner = THIS_MODULE,
	.release = kbase_stream_close,
};

int kbase_stream_create(const char *name, int *const out_fd)
{
	struct sync_timeline *tl;

	BUG_ON(!out_fd);

	tl = kbase_sync_timeline_alloc(name);
	if (!tl)
		return -EINVAL;

	*out_fd = anon_inode_getfd(name, &stream_fops, tl, O_RDONLY | O_CLOEXEC);

	if (*out_fd < 0) {
		sync_timeline_destroy(tl);
		return -EINVAL;
	}

	return 0;
}

int kbase_stream_create_fence(int tl_fd)
{
	struct sync_timeline *tl;
	struct sync_pt *pt;
	struct sync_fence *fence;
#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 7, 0)
	struct files_struct *files;
	struct fdtable *fdt;
#endif
	int fd;
	struct file *tl_file;

	tl_file = fget(tl_fd);
	if (tl_file == NULL)
		return -EBADF;

	if (tl_file->f_op != &stream_fops) {
		fd = -EBADF;
		goto out;
	}

	tl = tl_file->private_data;

	pt = kbase_sync_pt_alloc(tl);
	if (!pt) {
		fd = -EFAULT;
		goto out;
	}

	fence = sync_fence_create("mali_fence", pt);
	if (!fence) {
		sync_pt_free(pt);
		fd = -EFAULT;
		goto out;
	}

	/* from here the fence owns the sync_pt */

	/* create a fd representing the fence */
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 7, 0)
	fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
	if (fd < 0) {
		sync_fence_put(fence);
		goto out;
	}
#else
	fd = get_unused_fd();
	if (fd < 0) {
		sync_fence_put(fence);
		goto out;
	}

	files = current->files;
	spin_lock(&files->file_lock);
	fdt = files_fdtable(files);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 4, 0)
	__set_close_on_exec(fd, fdt);
#else
	FD_SET(fd, fdt->close_on_exec);
#endif
	spin_unlock(&files->file_lock);
#endif  /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 7, 0) */

	/* bind fence to the new fd */
	sync_fence_install(fence, fd);

 out:
	fput(tl_file);

	return fd;
}

int kbase_fence_validate(int fd)
{
	struct sync_fence *fence;

	fence = sync_fence_fdget(fd);
	if (!fence)
		return -EINVAL;

	sync_fence_put(fence);
	return 0;
}

#endif				/* CONFIG_SYNC */