root/drivers/media/dvb-core/dmxdev.c
// 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 = 0;

        if (!src->data)
                return 0;

        if (src->error) {
                ret = src->error;
                dvb_ringbuffer_flush(src);
                return ret;
        }

        for (todo = count; todo > 0; todo -= ret) {
                if (non_blocking && dvb_ringbuffer_empty(src)) {
                        ret = -EWOULDBLOCK;
                        break;
                }

                ret = wait_event_interruptible(src->queue,
                                               !dvb_ringbuffer_empty(src) ||
                                               (src->error != 0));
                if (ret < 0)
                        break;

                if (src->error) {
                        ret = src->error;
                        dvb_ringbuffer_flush(src);
                        break;
                }

                avail = dvb_ringbuffer_avail(src);
                if (avail > todo)
                        avail = todo;

                ret = dvb_ringbuffer_read_user(src, buf, avail);
                if (ret < 0)
                        break;

                buf += ret;
        }

        return (count - todo) ? (count - todo) : ret;
}

static struct dmx_frontend *get_fe(struct dmx_demux *demux, int type)
{
        struct list_head *head, *pos;

        head = demux->get_frontends(demux);
        if (!head)
                return NULL;
        list_for_each(pos, head)
                if (DMX_FE_ENTRY(pos)->source == type)
                        return DMX_FE_ENTRY(pos);

        return NULL;
}

static int dvb_dvr_open(struct inode *inode, struct file *file)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dmxdev *dmxdev = dvbdev->priv;
        struct dmx_frontend *front;
        bool need_ringbuffer = false;

        dprintk("%s\n", __func__);

        if (mutex_lock_interruptible(&dmxdev->mutex))
                return -ERESTARTSYS;

        if (dmxdev->exit) {
                mutex_unlock(&dmxdev->mutex);
                return -ENODEV;
        }

        dmxdev->may_do_mmap = 0;

        /*
         * The logic here is a little tricky due to the ifdef.
         *
         * The ringbuffer is used for both read and mmap.
         *
         * It is not needed, however, on two situations:
         *      - Write devices (access with O_WRONLY);
         *      - For duplex device nodes, opened with O_RDWR.
         */

        if ((file->f_flags & O_ACCMODE) == O_RDONLY)
                need_ringbuffer = true;
        else if ((file->f_flags & O_ACCMODE) == O_RDWR) {
                if (!(dmxdev->capabilities & DMXDEV_CAP_DUPLEX)) {
#ifdef CONFIG_DVB_MMAP
                        dmxdev->may_do_mmap = 1;
                        need_ringbuffer = true;
#else
                        mutex_unlock(&dmxdev->mutex);
                        return -EOPNOTSUPP;
#endif
                }
        }

        if (need_ringbuffer) {
                void *mem;

                if (!dvbdev->readers) {
                        mutex_unlock(&dmxdev->mutex);
                        return -EBUSY;
                }
                mem = vmalloc(DVR_BUFFER_SIZE);
                if (!mem) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ENOMEM;
                }
                dmxdev->dvr_buffer.data = mem;
                dmxdev->dvr_buffer.size = DVR_BUFFER_SIZE;
                dvb_ringbuffer_reset(&dmxdev->dvr_buffer);
                if (dmxdev->may_do_mmap)
                        dvb_vb2_init(&dmxdev->dvr_vb2_ctx, "dvr",
                                     &dmxdev->mutex,
                                     file->f_flags & O_NONBLOCK);
                dvbdev->readers--;
        }

        if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
                dmxdev->dvr_orig_fe = dmxdev->demux->frontend;

                if (!dmxdev->demux->write) {
                        mutex_unlock(&dmxdev->mutex);
                        return -EOPNOTSUPP;
                }

                front = get_fe(dmxdev->demux, DMX_MEMORY_FE);

                if (!front) {
                        mutex_unlock(&dmxdev->mutex);
                        return -EINVAL;
                }
                dmxdev->demux->disconnect_frontend(dmxdev->demux);
                dmxdev->demux->connect_frontend(dmxdev->demux, front);
        }
        dvbdev->users++;
        mutex_unlock(&dmxdev->mutex);
        return 0;
}

static int dvb_dvr_release(struct inode *inode, struct file *file)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dmxdev *dmxdev = dvbdev->priv;

        mutex_lock(&dmxdev->mutex);

        if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
                dmxdev->demux->disconnect_frontend(dmxdev->demux);
                dmxdev->demux->connect_frontend(dmxdev->demux,
                                                dmxdev->dvr_orig_fe);
        }

        if (((file->f_flags & O_ACCMODE) == O_RDONLY) ||
            dmxdev->may_do_mmap) {
                if (dmxdev->may_do_mmap) {
                        if (dvb_vb2_is_streaming(&dmxdev->dvr_vb2_ctx))
                                dvb_vb2_stream_off(&dmxdev->dvr_vb2_ctx);
                        dvb_vb2_release(&dmxdev->dvr_vb2_ctx);
                }
                dvbdev->readers++;
                if (dmxdev->dvr_buffer.data) {
                        void *mem = dmxdev->dvr_buffer.data;
                        /*memory barrier*/
                        mb();
                        spin_lock_irq(&dmxdev->lock);
                        dmxdev->dvr_buffer.data = NULL;
                        spin_unlock_irq(&dmxdev->lock);
                        vfree(mem);
                }
        }
        /* TODO */
        dvbdev->users--;
        if (dvbdev->users == 1 && dmxdev->exit == 1) {
                mutex_unlock(&dmxdev->mutex);
                wake_up(&dvbdev->wait_queue);
        } else
                mutex_unlock(&dmxdev->mutex);

        return 0;
}

static ssize_t dvb_dvr_write(struct file *file, const char __user *buf,
                             size_t count, loff_t *ppos)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dmxdev *dmxdev = dvbdev->priv;
        int ret;

        if (!dmxdev->demux->write)
                return -EOPNOTSUPP;
        if ((file->f_flags & O_ACCMODE) != O_WRONLY)
                return -EINVAL;
        if (mutex_lock_interruptible(&dmxdev->mutex))
                return -ERESTARTSYS;

        if (dmxdev->exit) {
                mutex_unlock(&dmxdev->mutex);
                return -ENODEV;
        }
        ret = dmxdev->demux->write(dmxdev->demux, buf, count);
        mutex_unlock(&dmxdev->mutex);
        return ret;
}

static ssize_t dvb_dvr_read(struct file *file, char __user *buf, size_t count,
                            loff_t *ppos)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dmxdev *dmxdev = dvbdev->priv;

        if (dmxdev->exit)
                return -ENODEV;

        return dvb_dmxdev_buffer_read(&dmxdev->dvr_buffer,
                                      file->f_flags & O_NONBLOCK,
                                      buf, count, ppos);
}

static int dvb_dvr_set_buffer_size(struct dmxdev *dmxdev,
                                      unsigned long size)
{
        struct dvb_ringbuffer *buf = &dmxdev->dvr_buffer;
        void *newmem;
        void *oldmem;

        dprintk("%s\n", __func__);

        if (buf->size == size)
                return 0;
        if (!size)
                return -EINVAL;

        newmem = vmalloc(size);
        if (!newmem)
                return -ENOMEM;

        oldmem = buf->data;

        spin_lock_irq(&dmxdev->lock);
        buf->data = newmem;
        buf->size = size;

        /* reset and not flush in case the buffer shrinks */
        dvb_ringbuffer_reset(buf);
        spin_unlock_irq(&dmxdev->lock);

        vfree(oldmem);

        return 0;
}

static inline void dvb_dmxdev_filter_state_set(struct dmxdev_filter
                                               *dmxdevfilter, int state)
{
        spin_lock_irq(&dmxdevfilter->dev->lock);
        dmxdevfilter->state = state;
        spin_unlock_irq(&dmxdevfilter->dev->lock);
}

static int dvb_dmxdev_set_buffer_size(struct dmxdev_filter *dmxdevfilter,
                                      unsigned long size)
{
        struct dvb_ringbuffer *buf = &dmxdevfilter->buffer;
        void *newmem;
        void *oldmem;

        if (buf->size == size)
                return 0;
        if (!size)
                return -EINVAL;
        if (dmxdevfilter->state >= DMXDEV_STATE_GO)
                return -EBUSY;

        newmem = vmalloc(size);
        if (!newmem)
                return -ENOMEM;

        oldmem = buf->data;

        spin_lock_irq(&dmxdevfilter->dev->lock);
        buf->data = newmem;
        buf->size = size;

        /* reset and not flush in case the buffer shrinks */
        dvb_ringbuffer_reset(buf);
        spin_unlock_irq(&dmxdevfilter->dev->lock);

        vfree(oldmem);

        return 0;
}

static void dvb_dmxdev_filter_timeout(struct timer_list *t)
{
        struct dmxdev_filter *dmxdevfilter = timer_container_of(dmxdevfilter,
                                                                t, timer);

        dmxdevfilter->buffer.error = -ETIMEDOUT;
        spin_lock_irq(&dmxdevfilter->dev->lock);
        dmxdevfilter->state = DMXDEV_STATE_TIMEDOUT;
        spin_unlock_irq(&dmxdevfilter->dev->lock);
        wake_up(&dmxdevfilter->buffer.queue);
}

static void dvb_dmxdev_filter_timer(struct dmxdev_filter *dmxdevfilter)
{
        struct dmx_sct_filter_params *para = &dmxdevfilter->params.sec;

        timer_delete(&dmxdevfilter->timer);
        if (para->timeout) {
                dmxdevfilter->timer.expires =
                    jiffies + 1 + (HZ / 2 + HZ * para->timeout) / 1000;
                add_timer(&dmxdevfilter->timer);
        }
}

static int dvb_dmxdev_section_callback(const u8 *buffer1, size_t buffer1_len,
                                       const u8 *buffer2, size_t buffer2_len,
                                       struct dmx_section_filter *filter,
                                       u32 *buffer_flags)
{
        struct dmxdev_filter *dmxdevfilter = filter->priv;
        int ret;

        if (!dvb_vb2_is_streaming(&dmxdevfilter->vb2_ctx) &&
            dmxdevfilter->buffer.error) {
                wake_up(&dmxdevfilter->buffer.queue);
                return 0;
        }
        spin_lock(&dmxdevfilter->dev->lock);
        if (dmxdevfilter->state != DMXDEV_STATE_GO) {
                spin_unlock(&dmxdevfilter->dev->lock);
                return 0;
        }
        timer_delete(&dmxdevfilter->timer);
        dprintk("section callback %*ph\n", 6, buffer1);
        if (dvb_vb2_is_streaming(&dmxdevfilter->vb2_ctx)) {
                ret = dvb_vb2_fill_buffer(&dmxdevfilter->vb2_ctx,
                                          buffer1, buffer1_len,
                                          buffer_flags, true);
                if (ret == buffer1_len)
                        ret = dvb_vb2_fill_buffer(&dmxdevfilter->vb2_ctx,
                                                  buffer2, buffer2_len,
                                                  buffer_flags, true);
        } else {
                ret = dvb_dmxdev_buffer_write(&dmxdevfilter->buffer,
                                              buffer1, buffer1_len);
                if (ret == buffer1_len) {
                        ret = dvb_dmxdev_buffer_write(&dmxdevfilter->buffer,
                                                      buffer2, buffer2_len);
                }
        }
        if (ret < 0)
                dmxdevfilter->buffer.error = ret;
        if (dmxdevfilter->params.sec.flags & DMX_ONESHOT)
                dmxdevfilter->state = DMXDEV_STATE_DONE;
        spin_unlock(&dmxdevfilter->dev->lock);
        wake_up(&dmxdevfilter->buffer.queue);
        return 0;
}

static int dvb_dmxdev_ts_callback(const u8 *buffer1, size_t buffer1_len,
                                  const u8 *buffer2, size_t buffer2_len,
                                  struct dmx_ts_feed *feed,
                                  u32 *buffer_flags)
{
        struct dmxdev_filter *dmxdevfilter = feed->priv;
        struct dvb_ringbuffer *buffer;
#ifdef CONFIG_DVB_MMAP
        struct dvb_vb2_ctx *ctx;
#endif
        int ret;

        spin_lock(&dmxdevfilter->dev->lock);
        if (dmxdevfilter->params.pes.output == DMX_OUT_DECODER) {
                spin_unlock(&dmxdevfilter->dev->lock);
                return 0;
        }

        if (dmxdevfilter->params.pes.output == DMX_OUT_TAP ||
            dmxdevfilter->params.pes.output == DMX_OUT_TSDEMUX_TAP) {
                buffer = &dmxdevfilter->buffer;
#ifdef CONFIG_DVB_MMAP
                ctx = &dmxdevfilter->vb2_ctx;
#endif
        } else {
                buffer = &dmxdevfilter->dev->dvr_buffer;
#ifdef CONFIG_DVB_MMAP
                ctx = &dmxdevfilter->dev->dvr_vb2_ctx;
#endif
        }

        if (dvb_vb2_is_streaming(ctx)) {
                ret = dvb_vb2_fill_buffer(ctx, buffer1, buffer1_len,
                                          buffer_flags, false);
                if (ret == buffer1_len)
                        ret = dvb_vb2_fill_buffer(ctx, buffer2, buffer2_len,
                                                  buffer_flags, false);
        } else {
                if (buffer->error) {
                        spin_unlock(&dmxdevfilter->dev->lock);
                        wake_up(&buffer->queue);
                        return 0;
                }
                ret = dvb_dmxdev_buffer_write(buffer, buffer1, buffer1_len);
                if (ret == buffer1_len)
                        ret = dvb_dmxdev_buffer_write(buffer,
                                                      buffer2, buffer2_len);
        }
        if (ret < 0)
                buffer->error = ret;
        spin_unlock(&dmxdevfilter->dev->lock);
        wake_up(&buffer->queue);
        return 0;
}

/* stop feed but only mark the specified filter as stopped (state set) */
static int dvb_dmxdev_feed_stop(struct dmxdev_filter *dmxdevfilter)
{
        struct dmxdev_feed *feed;

        dvb_dmxdev_filter_state_set(dmxdevfilter, DMXDEV_STATE_SET);

        switch (dmxdevfilter->type) {
        case DMXDEV_TYPE_SEC:
                timer_delete(&dmxdevfilter->timer);
                dmxdevfilter->feed.sec->stop_filtering(dmxdevfilter->feed.sec);
                break;
        case DMXDEV_TYPE_PES:
                list_for_each_entry(feed, &dmxdevfilter->feed.ts, next)
                        feed->ts->stop_filtering(feed->ts);
                break;
        default:
                return -EINVAL;
        }
        return 0;
}

/* start feed associated with the specified filter */
static int dvb_dmxdev_feed_start(struct dmxdev_filter *filter)
{
        struct dmxdev_feed *feed;
        int ret;

        dvb_dmxdev_filter_state_set(filter, DMXDEV_STATE_GO);

        switch (filter->type) {
        case DMXDEV_TYPE_SEC:
                return filter->feed.sec->start_filtering(filter->feed.sec);
        case DMXDEV_TYPE_PES:
                list_for_each_entry(feed, &filter->feed.ts, next) {
                        ret = feed->ts->start_filtering(feed->ts);
                        if (ret < 0) {
                                dvb_dmxdev_feed_stop(filter);
                                return ret;
                        }
                }
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

/* restart section feed if it has filters left associated with it,
   otherwise release the feed */
static int dvb_dmxdev_feed_restart(struct dmxdev_filter *filter)
{
        int i;
        struct dmxdev *dmxdev = filter->dev;
        u16 pid = filter->params.sec.pid;

        for (i = 0; i < dmxdev->filternum; i++)
                if (dmxdev->filter[i].state >= DMXDEV_STATE_GO &&
                    dmxdev->filter[i].type == DMXDEV_TYPE_SEC &&
                    dmxdev->filter[i].params.sec.pid == pid) {
                        dvb_dmxdev_feed_start(&dmxdev->filter[i]);
                        return 0;
                }

        filter->dev->demux->release_section_feed(dmxdev->demux,
                                                 filter->feed.sec);

        return 0;
}

static int dvb_dmxdev_filter_stop(struct dmxdev_filter *dmxdevfilter)
{
        struct dmxdev_feed *feed;
        struct dmx_demux *demux;

        if (dmxdevfilter->state < DMXDEV_STATE_GO)
                return 0;

        switch (dmxdevfilter->type) {
        case DMXDEV_TYPE_SEC:
                if (!dmxdevfilter->feed.sec)
                        break;
                dvb_dmxdev_feed_stop(dmxdevfilter);
                if (dmxdevfilter->filter.sec)
                        dmxdevfilter->feed.sec->
                            release_filter(dmxdevfilter->feed.sec,
                                           dmxdevfilter->filter.sec);
                dvb_dmxdev_feed_restart(dmxdevfilter);
                dmxdevfilter->feed.sec = NULL;
                break;
        case DMXDEV_TYPE_PES:
                dvb_dmxdev_feed_stop(dmxdevfilter);
                demux = dmxdevfilter->dev->demux;
                list_for_each_entry(feed, &dmxdevfilter->feed.ts, next) {
                        demux->release_ts_feed(demux, feed->ts);
                        feed->ts = NULL;
                }
                break;
        default:
                if (dmxdevfilter->state == DMXDEV_STATE_ALLOCATED)
                        return 0;
                return -EINVAL;
        }

        dvb_ringbuffer_flush(&dmxdevfilter->buffer);
        return 0;
}

static void dvb_dmxdev_delete_pids(struct dmxdev_filter *dmxdevfilter)
{
        struct dmxdev_feed *feed, *tmp;

        /* delete all PIDs */
        list_for_each_entry_safe(feed, tmp, &dmxdevfilter->feed.ts, next) {
                list_del(&feed->next);
                kfree(feed);
        }

        BUG_ON(!list_empty(&dmxdevfilter->feed.ts));
}

static inline int dvb_dmxdev_filter_reset(struct dmxdev_filter *dmxdevfilter)
{
        if (dmxdevfilter->state < DMXDEV_STATE_SET)
                return 0;

        if (dmxdevfilter->type == DMXDEV_TYPE_PES)
                dvb_dmxdev_delete_pids(dmxdevfilter);

        dmxdevfilter->type = DMXDEV_TYPE_NONE;
        dvb_dmxdev_filter_state_set(dmxdevfilter, DMXDEV_STATE_ALLOCATED);
        return 0;
}

static int dvb_dmxdev_start_feed(struct dmxdev *dmxdev,
                                 struct dmxdev_filter *filter,
                                 struct dmxdev_feed *feed)
{
        ktime_t timeout = ktime_set(0, 0);
        struct dmx_pes_filter_params *para = &filter->params.pes;
        enum dmx_output otype;
        int ret;
        int ts_type;
        enum dmx_ts_pes ts_pes;
        struct dmx_ts_feed *tsfeed;

        feed->ts = NULL;
        otype = para->output;

        ts_pes = para->pes_type;

        if (ts_pes < DMX_PES_OTHER)
                ts_type = TS_DECODER;
        else
                ts_type = 0;

        if (otype == DMX_OUT_TS_TAP)
                ts_type |= TS_PACKET;
        else if (otype == DMX_OUT_TSDEMUX_TAP)
                ts_type |= TS_PACKET | TS_DEMUX;
        else if (otype == DMX_OUT_TAP)
                ts_type |= TS_PACKET | TS_DEMUX | TS_PAYLOAD_ONLY;

        ret = dmxdev->demux->allocate_ts_feed(dmxdev->demux, &feed->ts,
                                              dvb_dmxdev_ts_callback);
        if (ret < 0)
                return ret;

        tsfeed = feed->ts;
        tsfeed->priv = filter;

        ret = tsfeed->set(tsfeed, feed->pid, ts_type, ts_pes, timeout);
        if (ret < 0) {
                dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
                return ret;
        }

        ret = tsfeed->start_filtering(tsfeed);
        if (ret < 0) {
                dmxdev->demux->release_ts_feed(dmxdev->demux, tsfeed);
                return ret;
        }

        return 0;
}

static int dvb_dmxdev_filter_start(struct dmxdev_filter *filter)
{
        struct dmxdev *dmxdev = filter->dev;
        struct dmxdev_feed *feed;
        void *mem;
        int ret, i;

        if (filter->state < DMXDEV_STATE_SET)
                return -EINVAL;

        if (filter->state >= DMXDEV_STATE_GO)
                dvb_dmxdev_filter_stop(filter);

        if (!filter->buffer.data) {
                mem = vmalloc(filter->buffer.size);
                if (!mem)
                        return -ENOMEM;
                spin_lock_irq(&filter->dev->lock);
                filter->buffer.data = mem;
                spin_unlock_irq(&filter->dev->lock);
        }

        dvb_ringbuffer_flush(&filter->buffer);

        switch (filter->type) {
        case DMXDEV_TYPE_SEC:
        {
                struct dmx_sct_filter_params *para = &filter->params.sec;
                struct dmx_section_filter **secfilter = &filter->filter.sec;
                struct dmx_section_feed **secfeed = &filter->feed.sec;

                *secfilter = NULL;
                *secfeed = NULL;


                /* find active filter/feed with same PID */
                for (i = 0; i < dmxdev->filternum; i++) {
                        if (dmxdev->filter[i].state >= DMXDEV_STATE_GO &&
                            dmxdev->filter[i].type == DMXDEV_TYPE_SEC &&
                            dmxdev->filter[i].params.sec.pid == para->pid) {
                                *secfeed = dmxdev->filter[i].feed.sec;
                                break;
                        }
                }

                /* if no feed found, try to allocate new one */
                if (!*secfeed) {
                        ret = dmxdev->demux->allocate_section_feed(dmxdev->demux,
                                                                   secfeed,
                                                                   dvb_dmxdev_section_callback);
                        if (!*secfeed) {
                                pr_err("DVB (%s): could not alloc feed\n",
                                       __func__);
                                return ret;
                        }

                        ret = (*secfeed)->set(*secfeed, para->pid,
                                              (para->flags & DMX_CHECK_CRC) ? 1 : 0);
                        if (ret < 0) {
                                pr_err("DVB (%s): could not set feed\n",
                                       __func__);
                                dvb_dmxdev_feed_restart(filter);
                                return ret;
                        }
                } else {
                        dvb_dmxdev_feed_stop(filter);
                }

                ret = (*secfeed)->allocate_filter(*secfeed, secfilter);
                if (ret < 0) {
                        dvb_dmxdev_feed_restart(filter);
                        *secfeed = NULL;
                        dprintk("could not get filter\n");
                        return ret;
                }

                (*secfilter)->priv = filter;

                memcpy(&((*secfilter)->filter_value[3]),
                       &(para->filter.filter[1]), DMX_FILTER_SIZE - 1);
                memcpy(&(*secfilter)->filter_mask[3],
                       &para->filter.mask[1], DMX_FILTER_SIZE - 1);
                memcpy(&(*secfilter)->filter_mode[3],
                       &para->filter.mode[1], DMX_FILTER_SIZE - 1);

                (*secfilter)->filter_value[0] = para->filter.filter[0];
                (*secfilter)->filter_mask[0] = para->filter.mask[0];
                (*secfilter)->filter_mode[0] = para->filter.mode[0];
                (*secfilter)->filter_mask[1] = 0;
                (*secfilter)->filter_mask[2] = 0;

                filter->todo = 0;

                ret = filter->feed.sec->start_filtering(filter->feed.sec);
                if (ret < 0)
                        return ret;

                dvb_dmxdev_filter_timer(filter);
                break;
        }
        case DMXDEV_TYPE_PES:
                list_for_each_entry(feed, &filter->feed.ts, next) {
                        ret = dvb_dmxdev_start_feed(dmxdev, filter, feed);
                        if (ret < 0) {
                                dvb_dmxdev_filter_stop(filter);
                                return ret;
                        }
                }
                break;
        default:
                return -EINVAL;
        }

        dvb_dmxdev_filter_state_set(filter, DMXDEV_STATE_GO);
        return 0;
}

static int dvb_demux_open(struct inode *inode, struct file *file)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dmxdev *dmxdev = dvbdev->priv;
        int i;
        struct dmxdev_filter *dmxdevfilter;

        if (!dmxdev->filter)
                return -EINVAL;

        if (mutex_lock_interruptible(&dmxdev->mutex))
                return -ERESTARTSYS;

        if (dmxdev->exit) {
                mutex_unlock(&dmxdev->mutex);
                return -ENODEV;
        }

        for (i = 0; i < dmxdev->filternum; i++)
                if (dmxdev->filter[i].state == DMXDEV_STATE_FREE)
                        break;

        if (i == dmxdev->filternum) {
                mutex_unlock(&dmxdev->mutex);
                return -EMFILE;
        }

        dmxdevfilter = &dmxdev->filter[i];
        mutex_init(&dmxdevfilter->mutex);
        file->private_data = dmxdevfilter;

#ifdef CONFIG_DVB_MMAP
        dmxdev->may_do_mmap = 1;
#else
        dmxdev->may_do_mmap = 0;
#endif

        /*
         * The mutex passed to dvb_vb2_init is unlocked when a buffer
         * is in a blocking wait. However, dmxdevfilter has two mutexes:
         * dmxdevfilter->mutex and dmxdev->mutex. So this will not work.
         * The solution would be to support unlocking two mutexes in vb2,
         * but since this problem has been here since the beginning and
         * nobody ever complained, we leave it as-is rather than adding
         * that second mutex pointer to vb2.
         *
         * In the unlikely event that someone complains about this, then
         * this comment will hopefully help.
         */
        dvb_ringbuffer_init(&dmxdevfilter->buffer, NULL, 8192);
        dvb_vb2_init(&dmxdevfilter->vb2_ctx, "demux_filter",
                     &dmxdevfilter->mutex, file->f_flags & O_NONBLOCK);
        dmxdevfilter->type = DMXDEV_TYPE_NONE;
        dvb_dmxdev_filter_state_set(dmxdevfilter, DMXDEV_STATE_ALLOCATED);
        timer_setup(&dmxdevfilter->timer, dvb_dmxdev_filter_timeout, 0);

        dvbdev->users++;

        mutex_unlock(&dmxdev->mutex);
        return 0;
}

static int dvb_dmxdev_filter_free(struct dmxdev *dmxdev,
                                  struct dmxdev_filter *dmxdevfilter)
{
        mutex_lock(&dmxdev->mutex);
        mutex_lock(&dmxdevfilter->mutex);
        if (dvb_vb2_is_streaming(&dmxdevfilter->vb2_ctx))
                dvb_vb2_stream_off(&dmxdevfilter->vb2_ctx);
        dvb_vb2_release(&dmxdevfilter->vb2_ctx);


        dvb_dmxdev_filter_stop(dmxdevfilter);
        dvb_dmxdev_filter_reset(dmxdevfilter);

        if (dmxdevfilter->buffer.data) {
                void *mem = dmxdevfilter->buffer.data;

                spin_lock_irq(&dmxdev->lock);
                dmxdevfilter->buffer.data = NULL;
                spin_unlock_irq(&dmxdev->lock);
                vfree(mem);
        }

        dvb_dmxdev_filter_state_set(dmxdevfilter, DMXDEV_STATE_FREE);
        wake_up(&dmxdevfilter->buffer.queue);
        mutex_unlock(&dmxdevfilter->mutex);
        mutex_unlock(&dmxdev->mutex);
        return 0;
}

static inline void invert_mode(struct dmx_filter *filter)
{
        int i;

        for (i = 0; i < DMX_FILTER_SIZE; i++)
                filter->mode[i] ^= 0xff;
}

static int dvb_dmxdev_add_pid(struct dmxdev *dmxdev,
                              struct dmxdev_filter *filter, u16 pid)
{
        struct dmxdev_feed *feed;

        if ((filter->type != DMXDEV_TYPE_PES) ||
            (filter->state < DMXDEV_STATE_SET))
                return -EINVAL;

        /* only TS packet filters may have multiple PIDs */
        if ((filter->params.pes.output != DMX_OUT_TSDEMUX_TAP) &&
            (!list_empty(&filter->feed.ts)))
                return -EINVAL;

        feed = kzalloc_obj(struct dmxdev_feed);
        if (feed == NULL)
                return -ENOMEM;

        feed->pid = pid;
        list_add(&feed->next, &filter->feed.ts);

        if (filter->state >= DMXDEV_STATE_GO)
                return dvb_dmxdev_start_feed(dmxdev, filter, feed);

        return 0;
}

static int dvb_dmxdev_remove_pid(struct dmxdev *dmxdev,
                                  struct dmxdev_filter *filter, u16 pid)
{
        struct dmxdev_feed *feed, *tmp;

        if ((filter->type != DMXDEV_TYPE_PES) ||
            (filter->state < DMXDEV_STATE_SET))
                return -EINVAL;

        list_for_each_entry_safe(feed, tmp, &filter->feed.ts, next) {
                if ((feed->pid == pid) && (feed->ts != NULL)) {
                        feed->ts->stop_filtering(feed->ts);
                        filter->dev->demux->release_ts_feed(filter->dev->demux,
                                                            feed->ts);
                        list_del(&feed->next);
                        kfree(feed);
                }
        }

        return 0;
}

static int dvb_dmxdev_filter_set(struct dmxdev *dmxdev,
                                 struct dmxdev_filter *dmxdevfilter,
                                 struct dmx_sct_filter_params *params)
{
        dprintk("%s: PID=0x%04x, flags=%02x, timeout=%d\n",
                __func__, params->pid, params->flags, params->timeout);

        dvb_dmxdev_filter_stop(dmxdevfilter);

        dmxdevfilter->type = DMXDEV_TYPE_SEC;
        memcpy(&dmxdevfilter->params.sec,
               params, sizeof(struct dmx_sct_filter_params));
        invert_mode(&dmxdevfilter->params.sec.filter);
        dvb_dmxdev_filter_state_set(dmxdevfilter, DMXDEV_STATE_SET);

        if (params->flags & DMX_IMMEDIATE_START)
                return dvb_dmxdev_filter_start(dmxdevfilter);

        return 0;
}

static int dvb_dmxdev_pes_filter_set(struct dmxdev *dmxdev,
                                     struct dmxdev_filter *dmxdevfilter,
                                     struct dmx_pes_filter_params *params)
{
        int ret;

        dvb_dmxdev_filter_stop(dmxdevfilter);
        dvb_dmxdev_filter_reset(dmxdevfilter);

        if ((unsigned int)params->pes_type > DMX_PES_OTHER)
                return -EINVAL;

        dmxdevfilter->type = DMXDEV_TYPE_PES;
        memcpy(&dmxdevfilter->params, params,
               sizeof(struct dmx_pes_filter_params));
        INIT_LIST_HEAD(&dmxdevfilter->feed.ts);

        dvb_dmxdev_filter_state_set(dmxdevfilter, DMXDEV_STATE_SET);

        ret = dvb_dmxdev_add_pid(dmxdev, dmxdevfilter,
                                 dmxdevfilter->params.pes.pid);
        if (ret < 0)
                return ret;

        if (params->flags & DMX_IMMEDIATE_START)
                return dvb_dmxdev_filter_start(dmxdevfilter);

        return 0;
}

static ssize_t dvb_dmxdev_read_sec(struct dmxdev_filter *dfil,
                                   struct file *file, char __user *buf,
                                   size_t count, loff_t *ppos)
{
        int result, hcount;
        int done = 0;

        if (dfil->todo <= 0) {
                hcount = 3 + dfil->todo;
                if (hcount > count)
                        hcount = count;
                result = dvb_dmxdev_buffer_read(&dfil->buffer,
                                                file->f_flags & O_NONBLOCK,
                                                buf, hcount, ppos);
                if (result < 0) {
                        dfil->todo = 0;
                        return result;
                }
                if (copy_from_user(dfil->secheader - dfil->todo, buf, result))
                        return -EFAULT;
                buf += result;
                done = result;
                count -= result;
                dfil->todo -= result;
                if (dfil->todo > -3)
                        return done;
                dfil->todo = ((dfil->secheader[1] << 8) | dfil->secheader[2]) & 0xfff;
                if (!count)
                        return done;
        }
        if (count > dfil->todo)
                count = dfil->todo;
        result = dvb_dmxdev_buffer_read(&dfil->buffer,
                                        file->f_flags & O_NONBLOCK,
                                        buf, count, ppos);
        if (result < 0)
                return result;
        dfil->todo -= result;
        return (result + done);
}

static ssize_t
dvb_demux_read(struct file *file, char __user *buf, size_t count,
               loff_t *ppos)
{
        struct dmxdev_filter *dmxdevfilter = file->private_data;
        int ret;

        if (mutex_lock_interruptible(&dmxdevfilter->mutex))
                return -ERESTARTSYS;

        if (dmxdevfilter->type == DMXDEV_TYPE_SEC)
                ret = dvb_dmxdev_read_sec(dmxdevfilter, file, buf, count, ppos);
        else
                ret = dvb_dmxdev_buffer_read(&dmxdevfilter->buffer,
                                             file->f_flags & O_NONBLOCK,
                                             buf, count, ppos);

        mutex_unlock(&dmxdevfilter->mutex);
        return ret;
}

static int dvb_demux_do_ioctl(struct file *file,
                              unsigned int cmd, void *parg)
{
        struct dmxdev_filter *dmxdevfilter = file->private_data;
        struct dmxdev *dmxdev = dmxdevfilter->dev;
        unsigned long arg = (unsigned long)parg;
        int ret = 0;

        if (mutex_lock_interruptible(&dmxdev->mutex))
                return -ERESTARTSYS;

        switch (cmd) {
        case DMX_START:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                if (dmxdevfilter->state < DMXDEV_STATE_SET)
                        ret = -EINVAL;
                else
                        ret = dvb_dmxdev_filter_start(dmxdevfilter);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_STOP:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_dmxdev_filter_stop(dmxdevfilter);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_SET_FILTER:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_dmxdev_filter_set(dmxdev, dmxdevfilter, parg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_SET_PES_FILTER:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_dmxdev_pes_filter_set(dmxdev, dmxdevfilter, parg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_SET_BUFFER_SIZE:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_dmxdev_set_buffer_size(dmxdevfilter, arg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_GET_PES_PIDS:
                if (!dmxdev->demux->get_pes_pids) {
                        ret = -EINVAL;
                        break;
                }
                dmxdev->demux->get_pes_pids(dmxdev->demux, parg);
                break;

        case DMX_GET_STC:
                if (!dmxdev->demux->get_stc) {
                        ret = -EINVAL;
                        break;
                }
                ret = dmxdev->demux->get_stc(dmxdev->demux,
                                             ((struct dmx_stc *)parg)->num,
                                             &((struct dmx_stc *)parg)->stc,
                                             &((struct dmx_stc *)parg)->base);
                break;

        case DMX_ADD_PID:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        ret = -ERESTARTSYS;
                        break;
                }
                ret = dvb_dmxdev_add_pid(dmxdev, dmxdevfilter, *(u16 *)parg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_REMOVE_PID:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        ret = -ERESTARTSYS;
                        break;
                }
                ret = dvb_dmxdev_remove_pid(dmxdev, dmxdevfilter, *(u16 *)parg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

#ifdef CONFIG_DVB_MMAP
        case DMX_REQBUFS:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_vb2_reqbufs(&dmxdevfilter->vb2_ctx, parg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_QUERYBUF:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_vb2_querybuf(&dmxdevfilter->vb2_ctx, parg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_EXPBUF:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_vb2_expbuf(&dmxdevfilter->vb2_ctx, parg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_QBUF:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_vb2_qbuf(&dmxdevfilter->vb2_ctx, parg);
                if (ret == 0 && !dvb_vb2_is_streaming(&dmxdevfilter->vb2_ctx))
                        ret = dvb_vb2_stream_on(&dmxdevfilter->vb2_ctx);
                mutex_unlock(&dmxdevfilter->mutex);
                break;

        case DMX_DQBUF:
                if (mutex_lock_interruptible(&dmxdevfilter->mutex)) {
                        mutex_unlock(&dmxdev->mutex);
                        return -ERESTARTSYS;
                }
                ret = dvb_vb2_dqbuf(&dmxdevfilter->vb2_ctx, parg);
                mutex_unlock(&dmxdevfilter->mutex);
                break;
#endif
        default:
                ret = -ENOTTY;
                break;
        }
        mutex_unlock(&dmxdev->mutex);
        return ret;
}

static long dvb_demux_ioctl(struct file *file, unsigned int cmd,
                            unsigned long arg)
{
        return dvb_usercopy(file, cmd, arg, dvb_demux_do_ioctl);
}

static __poll_t dvb_demux_poll(struct file *file, poll_table *wait)
{
        struct dmxdev_filter *dmxdevfilter = file->private_data;
        __poll_t mask = 0;

        poll_wait(file, &dmxdevfilter->buffer.queue, wait);

        if ((!dmxdevfilter) || dmxdevfilter->dev->exit)
                return EPOLLERR;
        if (dvb_vb2_is_streaming(&dmxdevfilter->vb2_ctx))
                return dvb_vb2_poll(&dmxdevfilter->vb2_ctx, file, wait);

        if (dmxdevfilter->state != DMXDEV_STATE_GO &&
            dmxdevfilter->state != DMXDEV_STATE_DONE &&
            dmxdevfilter->state != DMXDEV_STATE_TIMEDOUT)
                return 0;

        if (dmxdevfilter->buffer.error)
                mask |= (EPOLLIN | EPOLLRDNORM | EPOLLPRI | EPOLLERR);

        if (!dvb_ringbuffer_empty(&dmxdevfilter->buffer))
                mask |= (EPOLLIN | EPOLLRDNORM | EPOLLPRI);

        return mask;
}

#ifdef CONFIG_DVB_MMAP
static int dvb_demux_mmap(struct file *file, struct vm_area_struct *vma)
{
        struct dmxdev_filter *dmxdevfilter = file->private_data;
        struct dmxdev *dmxdev = dmxdevfilter->dev;

        if (!dmxdev->may_do_mmap)
                return -ENOTTY;

        return dvb_vb2_mmap(&dmxdevfilter->vb2_ctx, vma);
}
#endif

static int dvb_demux_release(struct inode *inode, struct file *file)
{
        struct dmxdev_filter *dmxdevfilter = file->private_data;
        struct dmxdev *dmxdev = dmxdevfilter->dev;
        int ret;

        ret = dvb_dmxdev_filter_free(dmxdev, dmxdevfilter);

        mutex_lock(&dmxdev->mutex);
        dmxdev->dvbdev->users--;
        if (dmxdev->dvbdev->users == 1 && dmxdev->exit == 1) {
                mutex_unlock(&dmxdev->mutex);
                wake_up(&dmxdev->dvbdev->wait_queue);
        } else
                mutex_unlock(&dmxdev->mutex);

        return ret;
}

static const struct file_operations dvb_demux_fops = {
        .owner = THIS_MODULE,
        .read = dvb_demux_read,
        .unlocked_ioctl = dvb_demux_ioctl,
        .compat_ioctl = dvb_demux_ioctl,
        .open = dvb_demux_open,
        .release = dvb_demux_release,
        .poll = dvb_demux_poll,
        .llseek = default_llseek,
#ifdef CONFIG_DVB_MMAP
        .mmap = dvb_demux_mmap,
#endif
};

static const struct dvb_device dvbdev_demux = {
        .priv = NULL,
        .users = 1,
        .writers = 1,
#if defined(CONFIG_MEDIA_CONTROLLER_DVB)
        .name = "dvb-demux",
#endif
        .fops = &dvb_demux_fops
};

static int dvb_dvr_do_ioctl(struct file *file,
                            unsigned int cmd, void *parg)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dmxdev *dmxdev = dvbdev->priv;
        unsigned long arg = (unsigned long)parg;
        int ret;

        if (mutex_lock_interruptible(&dmxdev->mutex))
                return -ERESTARTSYS;

        switch (cmd) {
        case DMX_SET_BUFFER_SIZE:
                ret = dvb_dvr_set_buffer_size(dmxdev, arg);
                break;

#ifdef CONFIG_DVB_MMAP
        case DMX_REQBUFS:
                ret = dvb_vb2_reqbufs(&dmxdev->dvr_vb2_ctx, parg);
                break;

        case DMX_QUERYBUF:
                ret = dvb_vb2_querybuf(&dmxdev->dvr_vb2_ctx, parg);
                break;

        case DMX_EXPBUF:
                ret = dvb_vb2_expbuf(&dmxdev->dvr_vb2_ctx, parg);
                break;

        case DMX_QBUF:
                ret = dvb_vb2_qbuf(&dmxdev->dvr_vb2_ctx, parg);
                if (ret == 0 && !dvb_vb2_is_streaming(&dmxdev->dvr_vb2_ctx))
                        ret = dvb_vb2_stream_on(&dmxdev->dvr_vb2_ctx);
                break;

        case DMX_DQBUF:
                ret = dvb_vb2_dqbuf(&dmxdev->dvr_vb2_ctx, parg);
                break;
#endif
        default:
                ret = -ENOTTY;
                break;
        }
        mutex_unlock(&dmxdev->mutex);
        return ret;
}

static long dvb_dvr_ioctl(struct file *file,
                         unsigned int cmd, unsigned long arg)
{
        return dvb_usercopy(file, cmd, arg, dvb_dvr_do_ioctl);
}

static __poll_t dvb_dvr_poll(struct file *file, poll_table *wait)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dmxdev *dmxdev = dvbdev->priv;
        __poll_t mask = 0;

        dprintk("%s\n", __func__);

        poll_wait(file, &dmxdev->dvr_buffer.queue, wait);

        if (dmxdev->exit)
                return EPOLLERR;
        if (dvb_vb2_is_streaming(&dmxdev->dvr_vb2_ctx))
                return dvb_vb2_poll(&dmxdev->dvr_vb2_ctx, file, wait);

        if (((file->f_flags & O_ACCMODE) == O_RDONLY) ||
            dmxdev->may_do_mmap) {
                if (dmxdev->dvr_buffer.error)
                        mask |= (EPOLLIN | EPOLLRDNORM | EPOLLPRI | EPOLLERR);

                if (!dvb_ringbuffer_empty(&dmxdev->dvr_buffer))
                        mask |= (EPOLLIN | EPOLLRDNORM | EPOLLPRI);
        } else
                mask |= (EPOLLOUT | EPOLLWRNORM | EPOLLPRI);

        return mask;
}

#ifdef CONFIG_DVB_MMAP
static int dvb_dvr_mmap(struct file *file, struct vm_area_struct *vma)
{
        struct dvb_device *dvbdev = file->private_data;
        struct dmxdev *dmxdev = dvbdev->priv;

        if (!dmxdev->may_do_mmap)
                return -ENOTTY;

        if (dmxdev->exit)
                return -ENODEV;

        return dvb_vb2_mmap(&dmxdev->dvr_vb2_ctx, vma);
}
#endif

static const struct file_operations dvb_dvr_fops = {
        .owner = THIS_MODULE,
        .read = dvb_dvr_read,
        .write = dvb_dvr_write,
        .unlocked_ioctl = dvb_dvr_ioctl,
        .open = dvb_dvr_open,
        .release = dvb_dvr_release,
        .poll = dvb_dvr_poll,
        .llseek = default_llseek,
#ifdef CONFIG_DVB_MMAP
        .mmap = dvb_dvr_mmap,
#endif
};

static const struct dvb_device dvbdev_dvr = {
        .priv = NULL,
        .readers = 1,
        .users = 1,
#if defined(CONFIG_MEDIA_CONTROLLER_DVB)
        .name = "dvb-dvr",
#endif
        .fops = &dvb_dvr_fops
};
int dvb_dmxdev_init(struct dmxdev *dmxdev, struct dvb_adapter *dvb_adapter)
{
        int i, ret;

        if (dmxdev->demux->open(dmxdev->demux) < 0)
                return -EUSERS;

        dmxdev->filter = vmalloc_array(dmxdev->filternum,
                                       sizeof(struct dmxdev_filter));
        if (!dmxdev->filter)
                return -ENOMEM;

        mutex_init(&dmxdev->mutex);
        spin_lock_init(&dmxdev->lock);
        for (i = 0; i < dmxdev->filternum; i++) {
                dmxdev->filter[i].dev = dmxdev;
                dmxdev->filter[i].buffer.data = NULL;
                dvb_dmxdev_filter_state_set(&dmxdev->filter[i],
                                            DMXDEV_STATE_FREE);
        }

        ret = dvb_register_device(dvb_adapter, &dmxdev->dvbdev, &dvbdev_demux, dmxdev,
                            DVB_DEVICE_DEMUX, dmxdev->filternum);
        if (ret < 0)
                goto err_register_dvbdev;

        ret = dvb_register_device(dvb_adapter, &dmxdev->dvr_dvbdev, &dvbdev_dvr,
                            dmxdev, DVB_DEVICE_DVR, dmxdev->filternum);
        if (ret < 0)
                goto err_register_dvr_dvbdev;

        dvb_ringbuffer_init(&dmxdev->dvr_buffer, NULL, 8192);

        return 0;

err_register_dvr_dvbdev:
        dvb_unregister_device(dmxdev->dvbdev);
err_register_dvbdev:
        vfree(dmxdev->filter);
        dmxdev->filter = NULL;
        return ret;
}

EXPORT_SYMBOL(dvb_dmxdev_init);

void dvb_dmxdev_release(struct dmxdev *dmxdev)
{
        mutex_lock(&dmxdev->mutex);
        dmxdev->exit = 1;
        mutex_unlock(&dmxdev->mutex);

        if (dmxdev->dvbdev->users > 1) {
                wait_event(dmxdev->dvbdev->wait_queue,
                                dmxdev->dvbdev->users == 1);
        }
        if (dmxdev->dvr_dvbdev->users > 1) {
                wait_event(dmxdev->dvr_dvbdev->wait_queue,
                                dmxdev->dvr_dvbdev->users == 1);
        }

        dvb_unregister_device(dmxdev->dvbdev);
        dvb_unregister_device(dmxdev->dvr_dvbdev);

        vfree(dmxdev->filter);
        dmxdev->filter = NULL;
        dmxdev->demux->close(dmxdev->demux);
}

EXPORT_SYMBOL(dvb_dmxdev_release);