// SPDX-License-Identifier: LGPL-2.1-or-later
/*
* dmxdev.c - DVB demultiplexer device
*
* Copyright (C) 2000 Ralph Metzler & Marcus Metzler
* for convergence integrated media GmbH
*/
#define pr_fmt(fmt) "dmxdev: " fmt
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/ioctl.h>
#include <linux/wait.h>
#include <linux/uaccess.h>
#include <media/dmxdev.h>
#include <media/dvb_vb2.h>
static int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off debugging (default:off).");
#define dprintk(fmt, arg...) do { \
if (debug) \
printk(KERN_DEBUG pr_fmt("%s: " fmt), \
__func__, ##arg); \
} while (0)
static int dvb_dmxdev_buffer_write(struct dvb_ringbuffer *buf,
const u8 *src, size_t len)
{
ssize_t free;
if (!len)
return 0;
if (!buf->data)
return 0;
free = dvb_ringbuffer_free(buf);
if (len > free) {
dprintk("buffer overflow\n");
return -EOVERFLOW;
}
return dvb_ringbuffer_write(buf, src, len);
}
static ssize_t dvb_dmxdev_buffer_read(struct dvb_ringbuffer *src,
int non_blocking, char __user *buf,
size_t count, loff_t *ppos)
{
size_t todo;
ssize_t avail;
ssize_t ret 