xref: /linux/drivers/media/dvb-core/dvb_demux.c (revision d7aa60d966461ca6114dc348e97889dc8850ff7f)
1 // SPDX-License-Identifier: LGPL-2.1-or-later
2 /*
3  * dvb_demux.c - DVB kernel demux API
4  *
5  * Copyright (C) 2000-2001 Ralph  Metzler <ralph@convergence.de>
6  *		       & Marcus Metzler <marcus@convergence.de>
7  *			 for convergence integrated media GmbH
8  */
9 
10 #define pr_fmt(fmt) "dvb_demux: " fmt
11 
12 #include <linux/sched/signal.h>
13 #include <linux/spinlock.h>
14 #include <linux/slab.h>
15 #include <linux/vmalloc.h>
16 #include <linux/module.h>
17 #include <linux/poll.h>
18 #include <linux/string.h>
19 #include <linux/crc32.h>
20 #include <linux/uaccess.h>
21 #include <asm/div64.h>
22 
23 #include <media/dvb_demux.h>
24 
25 static int dvb_demux_tscheck;
26 module_param(dvb_demux_tscheck, int, 0644);
27 MODULE_PARM_DESC(dvb_demux_tscheck,
28 		"enable transport stream continuity and TEI check");
29 
30 static int dvb_demux_speedcheck;
31 module_param(dvb_demux_speedcheck, int, 0644);
32 MODULE_PARM_DESC(dvb_demux_speedcheck,
33 		"enable transport stream speed check");
34 
35 static int dvb_demux_feed_err_pkts = 1;
36 module_param(dvb_demux_feed_err_pkts, int, 0644);
37 MODULE_PARM_DESC(dvb_demux_feed_err_pkts,
38 		 "when set to 0, drop packets with the TEI bit set (1 by default)");
39 
40 #define dprintk(fmt, arg...) \
41 	printk(KERN_DEBUG pr_fmt("%s: " fmt),  __func__, ##arg)
42 
43 #define dprintk_tscheck(x...) do {			\
44 	if (dvb_demux_tscheck && printk_ratelimit())	\
45 		dprintk(x);				\
46 } while (0)
47 
48 #ifdef CONFIG_DVB_DEMUX_SECTION_LOSS_LOG
49 #  define dprintk_sect_loss(x...) dprintk(x)
50 #else
51 #  define dprintk_sect_loss(x...)
52 #endif
53 
54 #define set_buf_flags(__feed, __flag)			\
55 	do {						\
56 		(__feed)->buffer_flags |= (__flag);	\
57 	} while (0)
58 
59 /******************************************************************************
60  * static inlined helper functions
61  ******************************************************************************/
62 
63 static inline u16 section_length(const u8 *buf)
64 {
65 	return 3 + ((buf[1] & 0x0f) << 8) + buf[2];
66 }
67 
68 static inline u16 ts_pid(const u8 *buf)
69 {
70 	return ((buf[1] & 0x1f) << 8) + buf[2];
71 }
72 
73 static inline u8 payload(const u8 *tsp)
74 {
75 	if (!(tsp[3] & 0x10))	// no payload?
76 		return 0;
77 
78 	if (tsp[3] & 0x20) {	// adaptation field?
79 		if (tsp[4] > 183)	// corrupted data?
80 			return 0;
81 		else
82 			return 184 - 1 - tsp[4];
83 	}
84 
85 	return 184;
86 }
87 
88 static u32 dvb_dmx_crc32(struct dvb_demux_feed *f, const u8 *src, size_t len)
89 {
90 	return (f->feed.sec.crc_val = crc32_be(f->feed.sec.crc_val, src, len));
91 }
92 
93 static void dvb_dmx_memcopy(struct dvb_demux_feed *f, u8 *d, const u8 *s,
94 			    size_t len)
95 {
96 	memcpy(d, s, len);
97 }
98 
99 /******************************************************************************
100  * Software filter functions
101  ******************************************************************************/
102 
103 static inline int dvb_dmx_swfilter_payload(struct dvb_demux_feed *feed,
104 					   const u8 *buf)
105 {
106 	int count = payload(buf);
107 	int p;
108 	int ccok;
109 	u8 cc;
110 
111 	if (count == 0)
112 		return -1;
113 
114 	p = 188 - count;
115 
116 	cc = buf[3] & 0x0f;
117 	ccok = ((feed->cc + 1) & 0x0f) == cc;
118 	if (!ccok) {
119 		set_buf_flags(feed, DMX_BUFFER_FLAG_DISCONTINUITY_DETECTED);
120 		dprintk_sect_loss("missed packet: %d instead of %d!\n",
121 				  cc, (feed->cc + 1) & 0x0f);
122 	}
123 	feed->cc = cc;
124 
125 	if (buf[1] & 0x40)	// PUSI ?
126 		feed->peslen = 0xfffa;
127 
128 	feed->peslen += count;
129 
130 	return feed->cb.ts(&buf[p], count, NULL, 0, &feed->feed.ts,
131 			   &feed->buffer_flags);
132 }
133 
134 static int dvb_dmx_swfilter_sectionfilter(struct dvb_demux_feed *feed,
135 					  struct dvb_demux_filter *f)
136 {
137 	u8 neq = 0;
138 	int i;
139 
140 	for (i = 0; i < DVB_DEMUX_MASK_MAX; i++) {
141 		u8 xor = f->filter.filter_value[i] ^ feed->feed.sec.secbuf[i];
142 
143 		if (f->maskandmode[i] & xor)
144 			return 0;
145 
146 		neq |= f->maskandnotmode[i] & xor;
147 	}
148 
149 	if (f->doneq && !neq)
150 		return 0;
151 
152 	return feed->cb.sec(feed->feed.sec.secbuf, feed->feed.sec.seclen,
153 			    NULL, 0, &f->filter, &feed->buffer_flags);
154 }
155 
156 static inline int dvb_dmx_swfilter_section_feed(struct dvb_demux_feed *feed)
157 {
158 	struct dvb_demux *demux = feed->demux;
159 	struct dvb_demux_filter *f = feed->filter;
160 	struct dmx_section_feed *sec = &feed->feed.sec;
161 	int section_syntax_indicator;
162 
163 	if (!sec->is_filtering)
164 		return 0;
165 
166 	if (!f)
167 		return 0;
168 
169 	if (sec->check_crc) {
170 		section_syntax_indicator = ((sec->secbuf[1] & 0x80) != 0);
171 		if (section_syntax_indicator &&
172 		    demux->check_crc32(feed, sec->secbuf, sec->seclen)) {
173 			set_buf_flags(feed, DMX_BUFFER_FLAG_HAD_CRC32_DISCARD);
174 			return -1;
175 		}
176 	}
177 
178 	do {
179 		if (dvb_dmx_swfilter_sectionfilter(feed, f) < 0)
180 			return -1;
181 	} while ((f = f->next) && sec->is_filtering);
182 
183 	sec->seclen = 0;
184 
185 	return 0;
186 }
187 
188 static void dvb_dmx_swfilter_section_new(struct dvb_demux_feed *feed)
189 {
190 	struct dmx_section_feed *sec = &feed->feed.sec;
191 
192 	if (sec->secbufp < sec->tsfeedp) {
193 		int n = sec->tsfeedp - sec->secbufp;
194 
195 		/*
196 		 * Section padding is done with 0xff bytes entirely.
197 		 * Due to speed reasons, we won't check all of them
198 		 * but just first and last.
199 		 */
200 		if (sec->secbuf[0] != 0xff || sec->secbuf[n - 1] != 0xff) {
201 			set_buf_flags(feed,
202 				      DMX_BUFFER_FLAG_DISCONTINUITY_DETECTED);
203 			dprintk_sect_loss("section ts padding loss: %d/%d\n",
204 					  n, sec->tsfeedp);
205 			dprintk_sect_loss("pad data: %*ph\n", n, sec->secbuf);
206 		}
207 	}
208 
209 	sec->tsfeedp = sec->secbufp = sec->seclen = 0;
210 	sec->secbuf = sec->secbuf_base;
211 }
212 
213 /*
214  * Losless Section Demux 1.4.1 by Emard
215  * Valsecchi Patrick:
216  *  - middle of section A  (no PUSI)
217  *  - end of section A and start of section B
218  *    (with PUSI pointing to the start of the second section)
219  *
220  *  In this case, without feed->pusi_seen you'll receive a garbage section
221  *  consisting of the end of section A. Basically because tsfeedp
222  *  is incemented and the use=0 condition is not raised
223  *  when the second packet arrives.
224  *
225  * Fix:
226  * when demux is started, let feed->pusi_seen = false to
227  * prevent initial feeding of garbage from the end of
228  * previous section. When you for the first time see PUSI=1
229  * then set feed->pusi_seen = true
230  */
231 static int dvb_dmx_swfilter_section_copy_dump(struct dvb_demux_feed *feed,
232 					      const u8 *buf, u8 len)
233 {
234 	struct dvb_demux *demux = feed->demux;
235 	struct dmx_section_feed *sec = &feed->feed.sec;
236 	u16 limit, seclen;
237 
238 	if (sec->tsfeedp >= DMX_MAX_SECFEED_SIZE)
239 		return 0;
240 
241 	if (sec->tsfeedp + len > DMX_MAX_SECFEED_SIZE) {
242 		set_buf_flags(feed, DMX_BUFFER_FLAG_DISCONTINUITY_DETECTED);
243 		dprintk_sect_loss("section buffer full loss: %d/%d\n",
244 				  sec->tsfeedp + len - DMX_MAX_SECFEED_SIZE,
245 				  DMX_MAX_SECFEED_SIZE);
246 		len = DMX_MAX_SECFEED_SIZE - sec->tsfeedp;
247 	}
248 
249 	if (len <= 0)
250 		return 0;
251 
252 	demux->memcopy(feed, sec->secbuf_base + sec->tsfeedp, buf, len);
253 	sec->tsfeedp += len;
254 
255 	/*
256 	 * Dump all the sections we can find in the data (Emard)
257 	 */
258 	limit = sec->tsfeedp;
259 	if (limit > DMX_MAX_SECFEED_SIZE)
260 		return -1;	/* internal error should never happen */
261 
262 	/* to be sure always set secbuf */
263 	sec->secbuf = sec->secbuf_base + sec->secbufp;
264 
265 	while (sec->secbufp + 2 < limit) {
266 		seclen = section_length(sec->secbuf);
267 		if (seclen <= 0 || seclen > DMX_MAX_SECTION_SIZE
268 		    || seclen + sec->secbufp > limit)
269 			return 0;
270 		sec->seclen = seclen;
271 		sec->crc_val = ~0;
272 		/* dump [secbuf .. secbuf+seclen) */
273 		if (feed->pusi_seen) {
274 			dvb_dmx_swfilter_section_feed(feed);
275 		} else {
276 			set_buf_flags(feed,
277 				      DMX_BUFFER_FLAG_DISCONTINUITY_DETECTED);
278 			dprintk_sect_loss("pusi not seen, discarding section data\n");
279 		}
280 		sec->secbufp += seclen;	/* secbufp and secbuf moving together is */
281 		sec->secbuf += seclen;	/* redundant but saves pointer arithmetic */
282 	}
283 
284 	return 0;
285 }
286 
287 static int dvb_dmx_swfilter_section_packet(struct dvb_demux_feed *feed,
288 					   const u8 *buf)
289 {
290 	u8 p, count;
291 	int ccok, dc_i = 0;
292 	u8 cc;
293 
294 	count = payload(buf);
295 
296 	if (count == 0)		/* count == 0 if no payload or out of range */
297 		return -1;
298 
299 	p = 188 - count;	/* payload start */
300 
301 	cc = buf[3] & 0x0f;
302 	ccok = ((feed->cc + 1) & 0x0f) == cc;
303 
304 	if (buf[3] & 0x20) {
305 		/* adaption field present, check for discontinuity_indicator */
306 		if ((buf[4] > 0) && (buf[5] & 0x80))
307 			dc_i = 1;
308 	}
309 
310 	if (!ccok || dc_i) {
311 		if (dc_i) {
312 			set_buf_flags(feed,
313 				      DMX_BUFFER_FLAG_DISCONTINUITY_INDICATOR);
314 			dprintk_sect_loss("%d frame with disconnect indicator\n",
315 				cc);
316 		} else {
317 			set_buf_flags(feed,
318 				      DMX_BUFFER_FLAG_DISCONTINUITY_DETECTED);
319 			dprintk_sect_loss("discontinuity: %d instead of %d. %d bytes lost\n",
320 				cc, (feed->cc + 1) & 0x0f, count + 4);
321 		}
322 		/*
323 		 * those bytes under some circumstances will again be reported
324 		 * in the following dvb_dmx_swfilter_section_new
325 		 */
326 
327 		/*
328 		 * Discontinuity detected. Reset pusi_seen to
329 		 * stop feeding of suspicious data until next PUSI=1 arrives
330 		 *
331 		 * FIXME: does it make sense if the MPEG-TS is the one
332 		 *	reporting discontinuity?
333 		 */
334 
335 		feed->pusi_seen = false;
336 		dvb_dmx_swfilter_section_new(feed);
337 	}
338 	feed->cc = cc;
339 
340 	if (buf[1] & 0x40) {
341 		/* PUSI=1 (is set), section boundary is here */
342 		if (count > 1 && buf[p] < count) {
343 			const u8 *before = &buf[p + 1];
344 			u8 before_len = buf[p];
345 			const u8 *after = &before[before_len];
346 			u8 after_len = count - 1 - before_len;
347 
348 			dvb_dmx_swfilter_section_copy_dump(feed, before,
349 							   before_len);
350 			/* before start of new section, set pusi_seen */
351 			feed->pusi_seen = true;
352 			dvb_dmx_swfilter_section_new(feed);
353 			dvb_dmx_swfilter_section_copy_dump(feed, after,
354 							   after_len);
355 		} else if (count > 0) {
356 			set_buf_flags(feed,
357 				      DMX_BUFFER_FLAG_DISCONTINUITY_DETECTED);
358 			dprintk_sect_loss("PUSI=1 but %d bytes lost\n", count);
359 		}
360 	} else {
361 		/* PUSI=0 (is not set), no section boundary */
362 		dvb_dmx_swfilter_section_copy_dump(feed, &buf[p], count);
363 	}
364 
365 	return 0;
366 }
367 
368 static inline void dvb_dmx_swfilter_packet_type(struct dvb_demux_feed *feed,
369 						const u8 *buf)
370 {
371 	switch (feed->type) {
372 	case DMX_TYPE_TS:
373 		if (!feed->feed.ts.is_filtering)
374 			break;
375 		if (feed->ts_type & TS_PACKET) {
376 			if (feed->ts_type & TS_PAYLOAD_ONLY)
377 				dvb_dmx_swfilter_payload(feed, buf);
378 			else
379 				feed->cb.ts(buf, 188, NULL, 0, &feed->feed.ts,
380 					    &feed->buffer_flags);
381 		}
382 		/* Used only on full-featured devices */
383 		if (feed->ts_type & TS_DECODER)
384 			if (feed->demux->write_to_decoder)
385 				feed->demux->write_to_decoder(feed, buf, 188);
386 		break;
387 
388 	case DMX_TYPE_SEC:
389 		if (!feed->feed.sec.is_filtering)
390 			break;
391 		if (dvb_dmx_swfilter_section_packet(feed, buf) < 0)
392 			feed->feed.sec.seclen = feed->feed.sec.secbufp = 0;
393 		break;
394 
395 	default:
396 		break;
397 	}
398 }
399 
400 #define DVR_FEED(f)							\
401 	(((f)->type == DMX_TYPE_TS) &&					\
402 	((f)->feed.ts.is_filtering) &&					\
403 	(((f)->ts_type & (TS_PACKET | TS_DEMUX)) == TS_PACKET))
404 
405 static void dvb_dmx_swfilter_packet(struct dvb_demux *demux, const u8 *buf)
406 {
407 	struct dvb_demux_feed *feed;
408 	u16 pid = ts_pid(buf);
409 	int dvr_done = 0;
410 
411 	if (dvb_demux_speedcheck) {
412 		ktime_t cur_time;
413 		u64 speed_bytes, speed_timedelta;
414 
415 		demux->speed_pkts_cnt++;
416 
417 		/* show speed every SPEED_PKTS_INTERVAL packets */
418 		if (!(demux->speed_pkts_cnt % SPEED_PKTS_INTERVAL)) {
419 			cur_time = ktime_get();
420 
421 			if (ktime_to_ns(demux->speed_last_time) != 0) {
422 				speed_bytes = (u64)demux->speed_pkts_cnt
423 					* 188 * 8;
424 				/* convert to 1024 basis */
425 				speed_bytes = 1000 * div64_u64(speed_bytes,
426 						1024);
427 				speed_timedelta = ktime_ms_delta(cur_time,
428 							demux->speed_last_time);
429 				if (speed_timedelta)
430 					dprintk("TS speed %llu Kbits/sec \n",
431 						div64_u64(speed_bytes,
432 							  speed_timedelta));
433 			}
434 
435 			demux->speed_last_time = cur_time;
436 			demux->speed_pkts_cnt = 0;
437 		}
438 	}
439 
440 	if (buf[1] & 0x80) {
441 		list_for_each_entry(feed, &demux->feed_list, list_head) {
442 			if ((feed->pid != pid) && (feed->pid != 0x2000))
443 				continue;
444 			set_buf_flags(feed, DMX_BUFFER_FLAG_TEI);
445 		}
446 		dprintk_tscheck("TEI detected. PID=0x%x data1=0x%x\n",
447 				pid, buf[1]);
448 		/* data in this packet can't be trusted - drop it unless
449 		 * module option dvb_demux_feed_err_pkts is set */
450 		if (!dvb_demux_feed_err_pkts)
451 			return;
452 	} else /* if TEI bit is set, pid may be wrong- skip pkt counter */
453 		if (demux->cnt_storage && dvb_demux_tscheck) {
454 			/* check pkt counter */
455 			if (pid < MAX_PID) {
456 				if (buf[3] & 0x10)
457 					demux->cnt_storage[pid] =
458 						(demux->cnt_storage[pid] + 1) & 0xf;
459 
460 				if ((buf[3] & 0xf) != demux->cnt_storage[pid]) {
461 					list_for_each_entry(feed, &demux->feed_list, list_head) {
462 						if ((feed->pid != pid) && (feed->pid != 0x2000))
463 							continue;
464 						set_buf_flags(feed,
465 							      DMX_BUFFER_PKT_COUNTER_MISMATCH);
466 					}
467 
468 					dprintk_tscheck("TS packet counter mismatch. PID=0x%x expected 0x%x got 0x%x\n",
469 							pid, demux->cnt_storage[pid],
470 							buf[3] & 0xf);
471 					demux->cnt_storage[pid] = buf[3] & 0xf;
472 				}
473 			}
474 			/* end check */
475 		}
476 
477 	list_for_each_entry(feed, &demux->feed_list, list_head) {
478 		if ((feed->pid != pid) && (feed->pid != 0x2000))
479 			continue;
480 
481 		/* copy each packet only once to the dvr device, even
482 		 * if a PID is in multiple filters (e.g. video + PCR) */
483 		if ((DVR_FEED(feed)) && (dvr_done++))
484 			continue;
485 
486 		if (feed->pid == pid)
487 			dvb_dmx_swfilter_packet_type(feed, buf);
488 		else if (feed->pid == 0x2000)
489 			feed->cb.ts(buf, 188, NULL, 0, &feed->feed.ts,
490 				    &feed->buffer_flags);
491 	}
492 }
493 
494 void dvb_dmx_swfilter_packets(struct dvb_demux *demux, const u8 *buf,
495 			      size_t count)
496 {
497 	unsigned long flags;
498 
499 	spin_lock_irqsave(&demux->lock, flags);
500 
501 	while (count--) {
502 		if (buf[0] == 0x47)
503 			dvb_dmx_swfilter_packet(demux, buf);
504 		buf += 188;
505 	}
506 
507 	spin_unlock_irqrestore(&demux->lock, flags);
508 }
509 
510 EXPORT_SYMBOL(dvb_dmx_swfilter_packets);
511 
512 static inline int find_next_packet(const u8 *buf, int pos, size_t count,
513 				   const int pktsize)
514 {
515 	int start = pos, lost;
516 
517 	while (pos < count) {
518 		if (buf[pos] == 0x47 ||
519 		    (pktsize == 204 && buf[pos] == 0xB8))
520 			break;
521 		pos++;
522 	}
523 
524 	lost = pos - start;
525 	if (lost) {
526 		/* This garbage is part of a valid packet? */
527 		int backtrack = pos - pktsize;
528 		if (backtrack >= 0 && (buf[backtrack] == 0x47 ||
529 		    (pktsize == 204 && buf[backtrack] == 0xB8)))
530 			return backtrack;
531 	}
532 
533 	return pos;
534 }
535 
536 /* Filter all pktsize= 188 or 204 sized packets and skip garbage. */
537 static inline void _dvb_dmx_swfilter(struct dvb_demux *demux, const u8 *buf,
538 		size_t count, const int pktsize)
539 {
540 	int p = 0, i, j;
541 	const u8 *q;
542 	unsigned long flags;
543 
544 	spin_lock_irqsave(&demux->lock, flags);
545 
546 	if (demux->tsbufp) { /* tsbuf[0] is now 0x47. */
547 		i = demux->tsbufp;
548 		j = pktsize - i;
549 		if (count < j) {
550 			memcpy(&demux->tsbuf[i], buf, count);
551 			demux->tsbufp += count;
552 			goto bailout;
553 		}
554 		memcpy(&demux->tsbuf[i], buf, j);
555 		if (demux->tsbuf[0] == 0x47) /* double check */
556 			dvb_dmx_swfilter_packet(demux, demux->tsbuf);
557 		demux->tsbufp = 0;
558 		p += j;
559 	}
560 
561 	while (1) {
562 		p = find_next_packet(buf, p, count, pktsize);
563 		if (p >= count)
564 			break;
565 		if (count - p < pktsize)
566 			break;
567 
568 		q = &buf[p];
569 
570 		if (pktsize == 204 && (*q == 0xB8)) {
571 			memcpy(demux->tsbuf, q, 188);
572 			demux->tsbuf[0] = 0x47;
573 			q = demux->tsbuf;
574 		}
575 		dvb_dmx_swfilter_packet(demux, q);
576 		p += pktsize;
577 	}
578 
579 	i = count - p;
580 	if (i) {
581 		memcpy(demux->tsbuf, &buf[p], i);
582 		demux->tsbufp = i;
583 		if (pktsize == 204 && demux->tsbuf[0] == 0xB8)
584 			demux->tsbuf[0] = 0x47;
585 	}
586 
587 bailout:
588 	spin_unlock_irqrestore(&demux->lock, flags);
589 }
590 
591 void dvb_dmx_swfilter(struct dvb_demux *demux, const u8 *buf, size_t count)
592 {
593 	_dvb_dmx_swfilter(demux, buf, count, 188);
594 }
595 EXPORT_SYMBOL(dvb_dmx_swfilter);
596 
597 void dvb_dmx_swfilter_204(struct dvb_demux *demux, const u8 *buf, size_t count)
598 {
599 	_dvb_dmx_swfilter(demux, buf, count, 204);
600 }
601 EXPORT_SYMBOL(dvb_dmx_swfilter_204);
602 
603 void dvb_dmx_swfilter_raw(struct dvb_demux *demux, const u8 *buf, size_t count)
604 {
605 	unsigned long flags;
606 
607 	spin_lock_irqsave(&demux->lock, flags);
608 
609 	demux->feed->cb.ts(buf, count, NULL, 0, &demux->feed->feed.ts,
610 			   &demux->feed->buffer_flags);
611 
612 	spin_unlock_irqrestore(&demux->lock, flags);
613 }
614 EXPORT_SYMBOL(dvb_dmx_swfilter_raw);
615 
616 static struct dvb_demux_filter *dvb_dmx_filter_alloc(struct dvb_demux *demux)
617 {
618 	int i;
619 
620 	for (i = 0; i < demux->filternum; i++)
621 		if (demux->filter[i].state == DMX_STATE_FREE)
622 			break;
623 
624 	if (i == demux->filternum)
625 		return NULL;
626 
627 	demux->filter[i].state = DMX_STATE_ALLOCATED;
628 
629 	return &demux->filter[i];
630 }
631 
632 static struct dvb_demux_feed *dvb_dmx_feed_alloc(struct dvb_demux *demux)
633 {
634 	int i;
635 
636 	for (i = 0; i < demux->feednum; i++)
637 		if (demux->feed[i].state == DMX_STATE_FREE)
638 			break;
639 
640 	if (i == demux->feednum)
641 		return NULL;
642 
643 	demux->feed[i].state = DMX_STATE_ALLOCATED;
644 
645 	return &demux->feed[i];
646 }
647 
648 static int dvb_demux_feed_find(struct dvb_demux_feed *feed)
649 {
650 	struct dvb_demux_feed *entry;
651 
652 	list_for_each_entry(entry, &feed->demux->feed_list, list_head)
653 		if (entry == feed)
654 			return 1;
655 
656 	return 0;
657 }
658 
659 static void dvb_demux_feed_add(struct dvb_demux_feed *feed)
660 {
661 	spin_lock_irq(&feed->demux->lock);
662 	if (dvb_demux_feed_find(feed)) {
663 		pr_err("%s: feed already in list (type=%x state=%x pid=%x)\n",
664 		       __func__, feed->type, feed->state, feed->pid);
665 		goto out;
666 	}
667 
668 	list_add(&feed->list_head, &feed->demux->feed_list);
669 out:
670 	spin_unlock_irq(&feed->demux->lock);
671 }
672 
673 static void dvb_demux_feed_del(struct dvb_demux_feed *feed)
674 {
675 	spin_lock_irq(&feed->demux->lock);
676 	if (!(dvb_demux_feed_find(feed))) {
677 		pr_err("%s: feed not in list (type=%x state=%x pid=%x)\n",
678 		       __func__, feed->type, feed->state, feed->pid);
679 		goto out;
680 	}
681 
682 	list_del(&feed->list_head);
683 out:
684 	spin_unlock_irq(&feed->demux->lock);
685 }
686 
687 static int dmx_ts_feed_set(struct dmx_ts_feed *ts_feed, u16 pid, int ts_type,
688 			   enum dmx_ts_pes pes_type, ktime_t timeout)
689 {
690 	struct dvb_demux_feed *feed = (struct dvb_demux_feed *)ts_feed;
691 	struct dvb_demux *demux = feed->demux;
692 
693 	if (pid > DMX_MAX_PID)
694 		return -EINVAL;
695 
696 	if (mutex_lock_interruptible(&demux->mutex))
697 		return -ERESTARTSYS;
698 
699 	if (ts_type & TS_DECODER) {
700 		if (pes_type >= DMX_PES_OTHER) {
701 			mutex_unlock(&demux->mutex);
702 			return -EINVAL;
703 		}
704 
705 		if (demux->pesfilter[pes_type] &&
706 		    demux->pesfilter[pes_type] != feed) {
707 			mutex_unlock(&demux->mutex);
708 			return -EINVAL;
709 		}
710 
711 		demux->pesfilter[pes_type] = feed;
712 		demux->pids[pes_type] = pid;
713 	}
714 
715 	dvb_demux_feed_add(feed);
716 
717 	feed->pid = pid;
718 	feed->timeout = timeout;
719 	feed->ts_type = ts_type;
720 	feed->pes_type = pes_type;
721 
722 	feed->state = DMX_STATE_READY;
723 	mutex_unlock(&demux->mutex);
724 
725 	return 0;
726 }
727 
728 static int dmx_ts_feed_start_filtering(struct dmx_ts_feed *ts_feed)
729 {
730 	struct dvb_demux_feed *feed = (struct dvb_demux_feed *)ts_feed;
731 	struct dvb_demux *demux = feed->demux;
732 	int ret;
733 
734 	if (mutex_lock_interruptible(&demux->mutex))
735 		return -ERESTARTSYS;
736 
737 	if (feed->state != DMX_STATE_READY || feed->type != DMX_TYPE_TS) {
738 		mutex_unlock(&demux->mutex);
739 		return -EINVAL;
740 	}
741 
742 	if (!demux->start_feed) {
743 		mutex_unlock(&demux->mutex);
744 		return -ENODEV;
745 	}
746 
747 	ret = demux->start_feed(feed);
748 	if (ret < 0) {
749 		mutex_unlock(&demux->mutex);
750 		return ret;
751 	}
752 
753 	spin_lock_irq(&demux->lock);
754 	ts_feed->is_filtering = 1;
755 	feed->state = DMX_STATE_GO;
756 	spin_unlock_irq(&demux->lock);
757 	mutex_unlock(&demux->mutex);
758 
759 	return 0;
760 }
761 
762 static int dmx_ts_feed_stop_filtering(struct dmx_ts_feed *ts_feed)
763 {
764 	struct dvb_demux_feed *feed = (struct dvb_demux_feed *)ts_feed;
765 	struct dvb_demux *demux = feed->demux;
766 	int ret;
767 
768 	mutex_lock(&demux->mutex);
769 
770 	if (feed->state < DMX_STATE_GO) {
771 		mutex_unlock(&demux->mutex);
772 		return -EINVAL;
773 	}
774 
775 	if (!demux->stop_feed) {
776 		mutex_unlock(&demux->mutex);
777 		return -ENODEV;
778 	}
779 
780 	ret = demux->stop_feed(feed);
781 
782 	spin_lock_irq(&demux->lock);
783 	ts_feed->is_filtering = 0;
784 	feed->state = DMX_STATE_ALLOCATED;
785 	spin_unlock_irq(&demux->lock);
786 	mutex_unlock(&demux->mutex);
787 
788 	return ret;
789 }
790 
791 static int dvbdmx_allocate_ts_feed(struct dmx_demux *dmx,
792 				   struct dmx_ts_feed **ts_feed,
793 				   dmx_ts_cb callback)
794 {
795 	struct dvb_demux *demux = (struct dvb_demux *)dmx;
796 	struct dvb_demux_feed *feed;
797 
798 	if (mutex_lock_interruptible(&demux->mutex))
799 		return -ERESTARTSYS;
800 
801 	feed = dvb_dmx_feed_alloc(demux);
802 	if (!feed) {
803 		mutex_unlock(&demux->mutex);
804 		return -EBUSY;
805 	}
806 
807 	feed->type = DMX_TYPE_TS;
808 	feed->cb.ts = callback;
809 	feed->demux = demux;
810 	feed->pid = 0xffff;
811 	feed->peslen = 0xfffa;
812 	feed->buffer_flags = 0;
813 
814 	(*ts_feed) = &feed->feed.ts;
815 	(*ts_feed)->parent = dmx;
816 	(*ts_feed)->priv = NULL;
817 	(*ts_feed)->is_filtering = 0;
818 	(*ts_feed)->start_filtering = dmx_ts_feed_start_filtering;
819 	(*ts_feed)->stop_filtering = dmx_ts_feed_stop_filtering;
820 	(*ts_feed)->set = dmx_ts_feed_set;
821 
822 	feed->filter = dvb_dmx_filter_alloc(demux);
823 	if (!feed->filter) {
824 		feed->state = DMX_STATE_FREE;
825 		mutex_unlock(&demux->mutex);
826 		return -EBUSY;
827 	}
828 
829 	feed->filter->type = DMX_TYPE_TS;
830 	feed->filter->feed = feed;
831 	feed->filter->state = DMX_STATE_READY;
832 
833 	mutex_unlock(&demux->mutex);
834 
835 	return 0;
836 }
837 
838 static int dvbdmx_release_ts_feed(struct dmx_demux *dmx,
839 				  struct dmx_ts_feed *ts_feed)
840 {
841 	struct dvb_demux *demux = (struct dvb_demux *)dmx;
842 	struct dvb_demux_feed *feed = (struct dvb_demux_feed *)ts_feed;
843 
844 	mutex_lock(&demux->mutex);
845 
846 	if (feed->state == DMX_STATE_FREE) {
847 		mutex_unlock(&demux->mutex);
848 		return -EINVAL;
849 	}
850 
851 	feed->state = DMX_STATE_FREE;
852 	feed->filter->state = DMX_STATE_FREE;
853 
854 	dvb_demux_feed_del(feed);
855 
856 	feed->pid = 0xffff;
857 
858 	if (feed->ts_type & TS_DECODER && feed->pes_type < DMX_PES_OTHER)
859 		demux->pesfilter[feed->pes_type] = NULL;
860 
861 	mutex_unlock(&demux->mutex);
862 	return 0;
863 }
864 
865 /******************************************************************************
866  * dmx_section_feed API calls
867  ******************************************************************************/
868 
869 static int dmx_section_feed_allocate_filter(struct dmx_section_feed *feed,
870 					    struct dmx_section_filter **filter)
871 {
872 	struct dvb_demux_feed *dvbdmxfeed = (struct dvb_demux_feed *)feed;
873 	struct dvb_demux *dvbdemux = dvbdmxfeed->demux;
874 	struct dvb_demux_filter *dvbdmxfilter;
875 
876 	if (mutex_lock_interruptible(&dvbdemux->mutex))
877 		return -ERESTARTSYS;
878 
879 	dvbdmxfilter = dvb_dmx_filter_alloc(dvbdemux);
880 	if (!dvbdmxfilter) {
881 		mutex_unlock(&dvbdemux->mutex);
882 		return -EBUSY;
883 	}
884 
885 	spin_lock_irq(&dvbdemux->lock);
886 	*filter = &dvbdmxfilter->filter;
887 	(*filter)->parent = feed;
888 	(*filter)->priv = NULL;
889 	dvbdmxfilter->feed = dvbdmxfeed;
890 	dvbdmxfilter->type = DMX_TYPE_SEC;
891 	dvbdmxfilter->state = DMX_STATE_READY;
892 	dvbdmxfilter->next = dvbdmxfeed->filter;
893 	dvbdmxfeed->filter = dvbdmxfilter;
894 	spin_unlock_irq(&dvbdemux->lock);
895 
896 	mutex_unlock(&dvbdemux->mutex);
897 	return 0;
898 }
899 
900 static int dmx_section_feed_set(struct dmx_section_feed *feed,
901 				u16 pid, int check_crc)
902 {
903 	struct dvb_demux_feed *dvbdmxfeed = (struct dvb_demux_feed *)feed;
904 	struct dvb_demux *dvbdmx = dvbdmxfeed->demux;
905 
906 	if (pid > 0x1fff)
907 		return -EINVAL;
908 
909 	if (mutex_lock_interruptible(&dvbdmx->mutex))
910 		return -ERESTARTSYS;
911 
912 	dvb_demux_feed_add(dvbdmxfeed);
913 
914 	dvbdmxfeed->pid = pid;
915 	dvbdmxfeed->feed.sec.check_crc = check_crc;
916 
917 	dvbdmxfeed->state = DMX_STATE_READY;
918 	mutex_unlock(&dvbdmx->mutex);
919 	return 0;
920 }
921 
922 static void prepare_secfilters(struct dvb_demux_feed *dvbdmxfeed)
923 {
924 	int i;
925 	struct dvb_demux_filter *f;
926 	struct dmx_section_filter *sf;
927 	u8 mask, mode, doneq;
928 
929 	f =  dvbdmxfeed->filter;
930 	if (!f)
931 		return;
932 	do {
933 		sf = &f->filter;
934 		doneq = false;
935 		for (i = 0; i < DVB_DEMUX_MASK_MAX; i++) {
936 			mode = sf->filter_mode[i];
937 			mask = sf->filter_mask[i];
938 			f->maskandmode[i] = mask & mode;
939 			doneq |= f->maskandnotmode[i] = mask & ~mode;
940 		}
941 		f->doneq = doneq ? true : false;
942 	} while ((f = f->next));
943 }
944 
945 static int dmx_section_feed_start_filtering(struct dmx_section_feed *feed)
946 {
947 	struct dvb_demux_feed *dvbdmxfeed = (struct dvb_demux_feed *)feed;
948 	struct dvb_demux *dvbdmx = dvbdmxfeed->demux;
949 	int ret;
950 
951 	if (mutex_lock_interruptible(&dvbdmx->mutex))
952 		return -ERESTARTSYS;
953 
954 	if (feed->is_filtering) {
955 		mutex_unlock(&dvbdmx->mutex);
956 		return -EBUSY;
957 	}
958 
959 	if (!dvbdmxfeed->filter) {
960 		mutex_unlock(&dvbdmx->mutex);
961 		return -EINVAL;
962 	}
963 
964 	dvbdmxfeed->feed.sec.tsfeedp = 0;
965 	dvbdmxfeed->feed.sec.secbuf = dvbdmxfeed->feed.sec.secbuf_base;
966 	dvbdmxfeed->feed.sec.secbufp = 0;
967 	dvbdmxfeed->feed.sec.seclen = 0;
968 	dvbdmxfeed->pusi_seen = false;
969 
970 	if (!dvbdmx->start_feed) {
971 		mutex_unlock(&dvbdmx->mutex);
972 		return -ENODEV;
973 	}
974 
975 	prepare_secfilters(dvbdmxfeed);
976 
977 	ret = dvbdmx->start_feed(dvbdmxfeed);
978 	if (ret < 0) {
979 		mutex_unlock(&dvbdmx->mutex);
980 		return ret;
981 	}
982 
983 	spin_lock_irq(&dvbdmx->lock);
984 	feed->is_filtering = 1;
985 	dvbdmxfeed->state = DMX_STATE_GO;
986 	spin_unlock_irq(&dvbdmx->lock);
987 
988 	mutex_unlock(&dvbdmx->mutex);
989 	return 0;
990 }
991 
992 static int dmx_section_feed_stop_filtering(struct dmx_section_feed *feed)
993 {
994 	struct dvb_demux_feed *dvbdmxfeed = (struct dvb_demux_feed *)feed;
995 	struct dvb_demux *dvbdmx = dvbdmxfeed->demux;
996 	int ret;
997 
998 	mutex_lock(&dvbdmx->mutex);
999 
1000 	if (!dvbdmx->stop_feed) {
1001 		mutex_unlock(&dvbdmx->mutex);
1002 		return -ENODEV;
1003 	}
1004 
1005 	ret = dvbdmx->stop_feed(dvbdmxfeed);
1006 
1007 	spin_lock_irq(&dvbdmx->lock);
1008 	dvbdmxfeed->state = DMX_STATE_READY;
1009 	feed->is_filtering = 0;
1010 	spin_unlock_irq(&dvbdmx->lock);
1011 
1012 	mutex_unlock(&dvbdmx->mutex);
1013 	return ret;
1014 }
1015 
1016 static int dmx_section_feed_release_filter(struct dmx_section_feed *feed,
1017 					   struct dmx_section_filter *filter)
1018 {
1019 	struct dvb_demux_filter *dvbdmxfilter = (struct dvb_demux_filter *)filter, *f;
1020 	struct dvb_demux_feed *dvbdmxfeed = (struct dvb_demux_feed *)feed;
1021 	struct dvb_demux *dvbdmx = dvbdmxfeed->demux;
1022 
1023 	mutex_lock(&dvbdmx->mutex);
1024 
1025 	if (dvbdmxfilter->feed != dvbdmxfeed) {
1026 		mutex_unlock(&dvbdmx->mutex);
1027 		return -EINVAL;
1028 	}
1029 
1030 	if (feed->is_filtering) {
1031 		/* release dvbdmx->mutex as far as it is
1032 		   acquired by stop_filtering() itself */
1033 		mutex_unlock(&dvbdmx->mutex);
1034 		feed->stop_filtering(feed);
1035 		mutex_lock(&dvbdmx->mutex);
1036 	}
1037 
1038 	spin_lock_irq(&dvbdmx->lock);
1039 	f = dvbdmxfeed->filter;
1040 
1041 	if (f == dvbdmxfilter) {
1042 		dvbdmxfeed->filter = dvbdmxfilter->next;
1043 	} else {
1044 		while (f->next != dvbdmxfilter)
1045 			f = f->next;
1046 		f->next = f->next->next;
1047 	}
1048 
1049 	dvbdmxfilter->state = DMX_STATE_FREE;
1050 	spin_unlock_irq(&dvbdmx->lock);
1051 	mutex_unlock(&dvbdmx->mutex);
1052 	return 0;
1053 }
1054 
1055 static int dvbdmx_allocate_section_feed(struct dmx_demux *demux,
1056 					struct dmx_section_feed **feed,
1057 					dmx_section_cb callback)
1058 {
1059 	struct dvb_demux *dvbdmx = (struct dvb_demux *)demux;
1060 	struct dvb_demux_feed *dvbdmxfeed;
1061 
1062 	if (mutex_lock_interruptible(&dvbdmx->mutex))
1063 		return -ERESTARTSYS;
1064 
1065 	dvbdmxfeed = dvb_dmx_feed_alloc(dvbdmx);
1066 	if (!dvbdmxfeed) {
1067 		mutex_unlock(&dvbdmx->mutex);
1068 		return -EBUSY;
1069 	}
1070 
1071 	dvbdmxfeed->type = DMX_TYPE_SEC;
1072 	dvbdmxfeed->cb.sec = callback;
1073 	dvbdmxfeed->demux = dvbdmx;
1074 	dvbdmxfeed->pid = 0xffff;
1075 	dvbdmxfeed->buffer_flags = 0;
1076 	dvbdmxfeed->feed.sec.secbuf = dvbdmxfeed->feed.sec.secbuf_base;
1077 	dvbdmxfeed->feed.sec.secbufp = dvbdmxfeed->feed.sec.seclen = 0;
1078 	dvbdmxfeed->feed.sec.tsfeedp = 0;
1079 	dvbdmxfeed->filter = NULL;
1080 
1081 	(*feed) = &dvbdmxfeed->feed.sec;
1082 	(*feed)->is_filtering = 0;
1083 	(*feed)->parent = demux;
1084 	(*feed)->priv = NULL;
1085 
1086 	(*feed)->set = dmx_section_feed_set;
1087 	(*feed)->allocate_filter = dmx_section_feed_allocate_filter;
1088 	(*feed)->start_filtering = dmx_section_feed_start_filtering;
1089 	(*feed)->stop_filtering = dmx_section_feed_stop_filtering;
1090 	(*feed)->release_filter = dmx_section_feed_release_filter;
1091 
1092 	mutex_unlock(&dvbdmx->mutex);
1093 	return 0;
1094 }
1095 
1096 static int dvbdmx_release_section_feed(struct dmx_demux *demux,
1097 				       struct dmx_section_feed *feed)
1098 {
1099 	struct dvb_demux_feed *dvbdmxfeed = (struct dvb_demux_feed *)feed;
1100 	struct dvb_demux *dvbdmx = (struct dvb_demux *)demux;
1101 
1102 	mutex_lock(&dvbdmx->mutex);
1103 
1104 	if (dvbdmxfeed->state == DMX_STATE_FREE) {
1105 		mutex_unlock(&dvbdmx->mutex);
1106 		return -EINVAL;
1107 	}
1108 	dvbdmxfeed->state = DMX_STATE_FREE;
1109 
1110 	dvb_demux_feed_del(dvbdmxfeed);
1111 
1112 	dvbdmxfeed->pid = 0xffff;
1113 
1114 	mutex_unlock(&dvbdmx->mutex);
1115 	return 0;
1116 }
1117 
1118 /******************************************************************************
1119  * dvb_demux kernel data API calls
1120  ******************************************************************************/
1121 
1122 static int dvbdmx_open(struct dmx_demux *demux)
1123 {
1124 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1125 
1126 	if (dvbdemux->users >= MAX_DVB_DEMUX_USERS)
1127 		return -EUSERS;
1128 
1129 	dvbdemux->users++;
1130 	return 0;
1131 }
1132 
1133 static int dvbdmx_close(struct dmx_demux *demux)
1134 {
1135 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1136 
1137 	if (dvbdemux->users == 0)
1138 		return -ENODEV;
1139 
1140 	dvbdemux->users--;
1141 	//FIXME: release any unneeded resources if users==0
1142 	return 0;
1143 }
1144 
1145 static int dvbdmx_write(struct dmx_demux *demux, const char __user *buf, size_t count)
1146 {
1147 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1148 	void *p;
1149 
1150 	if ((!demux->frontend) || (demux->frontend->source != DMX_MEMORY_FE))
1151 		return -EINVAL;
1152 
1153 	p = memdup_user(buf, count);
1154 	if (IS_ERR(p))
1155 		return PTR_ERR(p);
1156 	if (mutex_lock_interruptible(&dvbdemux->mutex)) {
1157 		kfree(p);
1158 		return -ERESTARTSYS;
1159 	}
1160 	dvb_dmx_swfilter(dvbdemux, p, count);
1161 	kfree(p);
1162 	mutex_unlock(&dvbdemux->mutex);
1163 
1164 	if (signal_pending(current))
1165 		return -EINTR;
1166 	return count;
1167 }
1168 
1169 static int dvbdmx_add_frontend(struct dmx_demux *demux,
1170 			       struct dmx_frontend *frontend)
1171 {
1172 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1173 	struct list_head *head = &dvbdemux->frontend_list;
1174 
1175 	list_add(&(frontend->connectivity_list), head);
1176 
1177 	return 0;
1178 }
1179 
1180 static int dvbdmx_remove_frontend(struct dmx_demux *demux,
1181 				  struct dmx_frontend *frontend)
1182 {
1183 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1184 	struct list_head *pos, *n, *head = &dvbdemux->frontend_list;
1185 
1186 	list_for_each_safe(pos, n, head) {
1187 		if (DMX_FE_ENTRY(pos) == frontend) {
1188 			list_del(pos);
1189 			return 0;
1190 		}
1191 	}
1192 
1193 	return -ENODEV;
1194 }
1195 
1196 static struct list_head *dvbdmx_get_frontends(struct dmx_demux *demux)
1197 {
1198 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1199 
1200 	if (list_empty(&dvbdemux->frontend_list))
1201 		return NULL;
1202 
1203 	return &dvbdemux->frontend_list;
1204 }
1205 
1206 static int dvbdmx_connect_frontend(struct dmx_demux *demux,
1207 				   struct dmx_frontend *frontend)
1208 {
1209 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1210 
1211 	if (demux->frontend)
1212 		return -EINVAL;
1213 
1214 	mutex_lock(&dvbdemux->mutex);
1215 
1216 	demux->frontend = frontend;
1217 	mutex_unlock(&dvbdemux->mutex);
1218 	return 0;
1219 }
1220 
1221 static int dvbdmx_disconnect_frontend(struct dmx_demux *demux)
1222 {
1223 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1224 
1225 	mutex_lock(&dvbdemux->mutex);
1226 
1227 	demux->frontend = NULL;
1228 	mutex_unlock(&dvbdemux->mutex);
1229 	return 0;
1230 }
1231 
1232 static int dvbdmx_get_pes_pids(struct dmx_demux *demux, u16 *pids)
1233 {
1234 	struct dvb_demux *dvbdemux = (struct dvb_demux *)demux;
1235 
1236 	memcpy(pids, dvbdemux->pids, 5 * sizeof(u16));
1237 	return 0;
1238 }
1239 
1240 int dvb_dmx_init(struct dvb_demux *dvbdemux)
1241 {
1242 	int i;
1243 	struct dmx_demux *dmx = &dvbdemux->dmx;
1244 
1245 	dvbdemux->cnt_storage = NULL;
1246 	dvbdemux->users = 0;
1247 	dvbdemux->filter = vmalloc_array(dvbdemux->filternum,
1248 					 sizeof(struct dvb_demux_filter));
1249 
1250 	if (!dvbdemux->filter)
1251 		return -ENOMEM;
1252 
1253 	dvbdemux->feed = vmalloc_array(dvbdemux->feednum,
1254 				       sizeof(struct dvb_demux_feed));
1255 	if (!dvbdemux->feed) {
1256 		vfree(dvbdemux->filter);
1257 		dvbdemux->filter = NULL;
1258 		return -ENOMEM;
1259 	}
1260 	for (i = 0; i < dvbdemux->filternum; i++) {
1261 		dvbdemux->filter[i].state = DMX_STATE_FREE;
1262 		dvbdemux->filter[i].index = i;
1263 	}
1264 	for (i = 0; i < dvbdemux->feednum; i++) {
1265 		dvbdemux->feed[i].state = DMX_STATE_FREE;
1266 		dvbdemux->feed[i].index = i;
1267 	}
1268 
1269 	dvbdemux->cnt_storage = vmalloc(MAX_PID + 1);
1270 	if (!dvbdemux->cnt_storage)
1271 		pr_warn("Couldn't allocate memory for TS/TEI check. Disabling it\n");
1272 
1273 	INIT_LIST_HEAD(&dvbdemux->frontend_list);
1274 
1275 	for (i = 0; i < DMX_PES_OTHER; i++) {
1276 		dvbdemux->pesfilter[i] = NULL;
1277 		dvbdemux->pids[i] = 0xffff;
1278 	}
1279 
1280 	INIT_LIST_HEAD(&dvbdemux->feed_list);
1281 
1282 	dvbdemux->playing = 0;
1283 	dvbdemux->recording = 0;
1284 	dvbdemux->tsbufp = 0;
1285 
1286 	if (!dvbdemux->check_crc32)
1287 		dvbdemux->check_crc32 = dvb_dmx_crc32;
1288 
1289 	if (!dvbdemux->memcopy)
1290 		dvbdemux->memcopy = dvb_dmx_memcopy;
1291 
1292 	dmx->frontend = NULL;
1293 	dmx->priv = dvbdemux;
1294 	dmx->open = dvbdmx_open;
1295 	dmx->close = dvbdmx_close;
1296 	dmx->write = dvbdmx_write;
1297 	dmx->allocate_ts_feed = dvbdmx_allocate_ts_feed;
1298 	dmx->release_ts_feed = dvbdmx_release_ts_feed;
1299 	dmx->allocate_section_feed = dvbdmx_allocate_section_feed;
1300 	dmx->release_section_feed = dvbdmx_release_section_feed;
1301 
1302 	dmx->add_frontend = dvbdmx_add_frontend;
1303 	dmx->remove_frontend = dvbdmx_remove_frontend;
1304 	dmx->get_frontends = dvbdmx_get_frontends;
1305 	dmx->connect_frontend = dvbdmx_connect_frontend;
1306 	dmx->disconnect_frontend = dvbdmx_disconnect_frontend;
1307 	dmx->get_pes_pids = dvbdmx_get_pes_pids;
1308 
1309 	mutex_init(&dvbdemux->mutex);
1310 	spin_lock_init(&dvbdemux->lock);
1311 
1312 	return 0;
1313 }
1314 
1315 EXPORT_SYMBOL(dvb_dmx_init);
1316 
1317 void dvb_dmx_release(struct dvb_demux *dvbdemux)
1318 {
1319 	vfree(dvbdemux->cnt_storage);
1320 	vfree(dvbdemux->filter);
1321 	vfree(dvbdemux->feed);
1322 }
1323 
1324 EXPORT_SYMBOL(dvb_dmx_release);
1325