V4L/DVB (5123): Buf_qbuf: fix: videobuf_queue->stream corruption and lockup
[linux-2.6] / drivers / ieee1394 / ieee1394_transactions.c
1 /*
2  * IEEE 1394 for Linux
3  *
4  * Transaction support.
5  *
6  * Copyright (C) 1999 Andreas E. Bombe
7  *
8  * This code is licensed under the GPL.  See the file COPYING in the root
9  * directory of the kernel sources for details.
10  */
11
12 #include <linux/bitops.h>
13 #include <linux/spinlock.h>
14 #include <linux/wait.h>
15
16 #include <asm/bug.h>
17 #include <asm/errno.h>
18
19 #include "ieee1394.h"
20 #include "ieee1394_types.h"
21 #include "hosts.h"
22 #include "ieee1394_core.h"
23 #include "ieee1394_transactions.h"
24
25 #define PREP_ASYNC_HEAD_ADDRESS(tc) \
26         packet->tcode = tc; \
27         packet->header[0] = (packet->node_id << 16) | (packet->tlabel << 10) \
28                 | (1 << 8) | (tc << 4); \
29         packet->header[1] = (packet->host->node_id << 16) | (addr >> 32); \
30         packet->header[2] = addr & 0xffffffff
31
32 #ifndef HPSB_DEBUG_TLABELS
33 static
34 #endif
35 spinlock_t hpsb_tlabel_lock = SPIN_LOCK_UNLOCKED;
36
37 static DECLARE_WAIT_QUEUE_HEAD(tlabel_wq);
38
39 static void fill_async_readquad(struct hpsb_packet *packet, u64 addr)
40 {
41         PREP_ASYNC_HEAD_ADDRESS(TCODE_READQ);
42         packet->header_size = 12;
43         packet->data_size = 0;
44         packet->expect_response = 1;
45 }
46
47 static void fill_async_readblock(struct hpsb_packet *packet, u64 addr,
48                                  int length)
49 {
50         PREP_ASYNC_HEAD_ADDRESS(TCODE_READB);
51         packet->header[3] = length << 16;
52         packet->header_size = 16;
53         packet->data_size = 0;
54         packet->expect_response = 1;
55 }
56
57 static void fill_async_writequad(struct hpsb_packet *packet, u64 addr,
58                                  quadlet_t data)
59 {
60         PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEQ);
61         packet->header[3] = data;
62         packet->header_size = 16;
63         packet->data_size = 0;
64         packet->expect_response = 1;
65 }
66
67 static void fill_async_writeblock(struct hpsb_packet *packet, u64 addr,
68                                   int length)
69 {
70         PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEB);
71         packet->header[3] = length << 16;
72         packet->header_size = 16;
73         packet->expect_response = 1;
74         packet->data_size = length + (length % 4 ? 4 - (length % 4) : 0);
75 }
76
77 static void fill_async_lock(struct hpsb_packet *packet, u64 addr, int extcode,
78                             int length)
79 {
80         PREP_ASYNC_HEAD_ADDRESS(TCODE_LOCK_REQUEST);
81         packet->header[3] = (length << 16) | extcode;
82         packet->header_size = 16;
83         packet->data_size = length;
84         packet->expect_response = 1;
85 }
86
87 static void fill_iso_packet(struct hpsb_packet *packet, int length, int channel,
88                             int tag, int sync)
89 {
90         packet->header[0] = (length << 16) | (tag << 14) | (channel << 8)
91             | (TCODE_ISO_DATA << 4) | sync;
92
93         packet->header_size = 4;
94         packet->data_size = length;
95         packet->type = hpsb_iso;
96         packet->tcode = TCODE_ISO_DATA;
97 }
98
99 static void fill_phy_packet(struct hpsb_packet *packet, quadlet_t data)
100 {
101         packet->header[0] = data;
102         packet->header[1] = ~data;
103         packet->header_size = 8;
104         packet->data_size = 0;
105         packet->expect_response = 0;
106         packet->type = hpsb_raw;        /* No CRC added */
107         packet->speed_code = IEEE1394_SPEED_100;        /* Force speed to be 100Mbps */
108 }
109
110 static void fill_async_stream_packet(struct hpsb_packet *packet, int length,
111                                      int channel, int tag, int sync)
112 {
113         packet->header[0] = (length << 16) | (tag << 14) | (channel << 8)
114             | (TCODE_STREAM_DATA << 4) | sync;
115
116         packet->header_size = 4;
117         packet->data_size = length;
118         packet->type = hpsb_async;
119         packet->tcode = TCODE_ISO_DATA;
120 }
121
122 /* same as hpsb_get_tlabel, except that it returns immediately */
123 static int hpsb_get_tlabel_atomic(struct hpsb_packet *packet)
124 {
125         unsigned long flags, *tp;
126         u8 *next;
127         int tlabel, n = NODEID_TO_NODE(packet->node_id);
128
129         /* Broadcast transactions are complete once the request has been sent.
130          * Use the same transaction label for all broadcast transactions. */
131         if (unlikely(n == ALL_NODES)) {
132                 packet->tlabel = 0;
133                 return 0;
134         }
135         tp = packet->host->tl_pool[n].map;
136         next = &packet->host->next_tl[n];
137
138         spin_lock_irqsave(&hpsb_tlabel_lock, flags);
139         tlabel = find_next_zero_bit(tp, 64, *next);
140         if (tlabel > 63)
141                 tlabel = find_first_zero_bit(tp, 64);
142         if (tlabel > 63) {
143                 spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
144                 return -EAGAIN;
145         }
146         __set_bit(tlabel, tp);
147         *next = (tlabel + 1) & 63;
148         spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
149
150         packet->tlabel = tlabel;
151         return 0;
152 }
153
154 /**
155  * hpsb_get_tlabel - allocate a transaction label
156  * @packet: the packet whose tlabel and tl_pool we set
157  *
158  * Every asynchronous transaction on the 1394 bus needs a transaction
159  * label to match the response to the request.  This label has to be
160  * different from any other transaction label in an outstanding request to
161  * the same node to make matching possible without ambiguity.
162  *
163  * There are 64 different tlabels, so an allocated tlabel has to be freed
164  * with hpsb_free_tlabel() after the transaction is complete (unless it's
165  * reused again for the same target node).
166  *
167  * Return value: Zero on success, otherwise non-zero. A non-zero return
168  * generally means there are no available tlabels. If this is called out
169  * of interrupt or atomic context, then it will sleep until can return a
170  * tlabel or a signal is received.
171  */
172 int hpsb_get_tlabel(struct hpsb_packet *packet)
173 {
174         if (irqs_disabled() || in_atomic())
175                 return hpsb_get_tlabel_atomic(packet);
176
177         /* NB: The macro wait_event_interruptible() is called with a condition
178          * argument with side effect.  This is only possible because the side
179          * effect does not occur until the condition became true, and
180          * wait_event_interruptible() won't evaluate the condition again after
181          * that. */
182         return wait_event_interruptible(tlabel_wq,
183                                         !hpsb_get_tlabel_atomic(packet));
184 }
185
186 /**
187  * hpsb_free_tlabel - free an allocated transaction label
188  * @packet: packet whose tlabel and tl_pool needs to be cleared
189  *
190  * Frees the transaction label allocated with hpsb_get_tlabel().  The
191  * tlabel has to be freed after the transaction is complete (i.e. response
192  * was received for a split transaction or packet was sent for a unified
193  * transaction).
194  *
195  * A tlabel must not be freed twice.
196  */
197 void hpsb_free_tlabel(struct hpsb_packet *packet)
198 {
199         unsigned long flags, *tp;
200         int tlabel, n = NODEID_TO_NODE(packet->node_id);
201
202         if (unlikely(n == ALL_NODES))
203                 return;
204         tp = packet->host->tl_pool[n].map;
205         tlabel = packet->tlabel;
206         BUG_ON(tlabel > 63 || tlabel < 0);
207
208         spin_lock_irqsave(&hpsb_tlabel_lock, flags);
209         BUG_ON(!__test_and_clear_bit(tlabel, tp));
210         spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
211
212         wake_up_interruptible(&tlabel_wq);
213 }
214
215 int hpsb_packet_success(struct hpsb_packet *packet)
216 {
217         switch (packet->ack_code) {
218         case ACK_PENDING:
219                 switch ((packet->header[1] >> 12) & 0xf) {
220                 case RCODE_COMPLETE:
221                         return 0;
222                 case RCODE_CONFLICT_ERROR:
223                         return -EAGAIN;
224                 case RCODE_DATA_ERROR:
225                         return -EREMOTEIO;
226                 case RCODE_TYPE_ERROR:
227                         return -EACCES;
228                 case RCODE_ADDRESS_ERROR:
229                         return -EINVAL;
230                 default:
231                         HPSB_ERR("received reserved rcode %d from node %d",
232                                  (packet->header[1] >> 12) & 0xf,
233                                  packet->node_id);
234                         return -EAGAIN;
235                 }
236                 BUG();
237
238         case ACK_BUSY_X:
239         case ACK_BUSY_A:
240         case ACK_BUSY_B:
241                 return -EBUSY;
242
243         case ACK_TYPE_ERROR:
244                 return -EACCES;
245
246         case ACK_COMPLETE:
247                 if (packet->tcode == TCODE_WRITEQ
248                     || packet->tcode == TCODE_WRITEB) {
249                         return 0;
250                 } else {
251                         HPSB_ERR("impossible ack_complete from node %d "
252                                  "(tcode %d)", packet->node_id, packet->tcode);
253                         return -EAGAIN;
254                 }
255
256         case ACK_DATA_ERROR:
257                 if (packet->tcode == TCODE_WRITEB
258                     || packet->tcode == TCODE_LOCK_REQUEST) {
259                         return -EAGAIN;
260                 } else {
261                         HPSB_ERR("impossible ack_data_error from node %d "
262                                  "(tcode %d)", packet->node_id, packet->tcode);
263                         return -EAGAIN;
264                 }
265
266         case ACK_ADDRESS_ERROR:
267                 return -EINVAL;
268
269         case ACK_TARDY:
270         case ACK_CONFLICT_ERROR:
271         case ACKX_NONE:
272         case ACKX_SEND_ERROR:
273         case ACKX_ABORTED:
274         case ACKX_TIMEOUT:
275                 /* error while sending */
276                 return -EAGAIN;
277
278         default:
279                 HPSB_ERR("got invalid ack %d from node %d (tcode %d)",
280                          packet->ack_code, packet->node_id, packet->tcode);
281                 return -EAGAIN;
282         }
283         BUG();
284 }
285
286 struct hpsb_packet *hpsb_make_readpacket(struct hpsb_host *host, nodeid_t node,
287                                          u64 addr, size_t length)
288 {
289         struct hpsb_packet *packet;
290
291         if (length == 0)
292                 return NULL;
293
294         packet = hpsb_alloc_packet(length);
295         if (!packet)
296                 return NULL;
297
298         packet->host = host;
299         packet->node_id = node;
300
301         if (hpsb_get_tlabel(packet)) {
302                 hpsb_free_packet(packet);
303                 return NULL;
304         }
305
306         if (length == 4)
307                 fill_async_readquad(packet, addr);
308         else
309                 fill_async_readblock(packet, addr, length);
310
311         return packet;
312 }
313
314 struct hpsb_packet *hpsb_make_writepacket(struct hpsb_host *host, nodeid_t node,
315                                           u64 addr, quadlet_t * buffer,
316                                           size_t length)
317 {
318         struct hpsb_packet *packet;
319
320         if (length == 0)
321                 return NULL;
322
323         packet = hpsb_alloc_packet(length);
324         if (!packet)
325                 return NULL;
326
327         if (length % 4) {       /* zero padding bytes */
328                 packet->data[length >> 2] = 0;
329         }
330         packet->host = host;
331         packet->node_id = node;
332
333         if (hpsb_get_tlabel(packet)) {
334                 hpsb_free_packet(packet);
335                 return NULL;
336         }
337
338         if (length == 4) {
339                 fill_async_writequad(packet, addr, buffer ? *buffer : 0);
340         } else {
341                 fill_async_writeblock(packet, addr, length);
342                 if (buffer)
343                         memcpy(packet->data, buffer, length);
344         }
345
346         return packet;
347 }
348
349 struct hpsb_packet *hpsb_make_streampacket(struct hpsb_host *host, u8 * buffer,
350                                            int length, int channel, int tag,
351                                            int sync)
352 {
353         struct hpsb_packet *packet;
354
355         if (length == 0)
356                 return NULL;
357
358         packet = hpsb_alloc_packet(length);
359         if (!packet)
360                 return NULL;
361
362         if (length % 4) {       /* zero padding bytes */
363                 packet->data[length >> 2] = 0;
364         }
365         packet->host = host;
366
367         if (hpsb_get_tlabel(packet)) {
368                 hpsb_free_packet(packet);
369                 return NULL;
370         }
371
372         fill_async_stream_packet(packet, length, channel, tag, sync);
373         if (buffer)
374                 memcpy(packet->data, buffer, length);
375
376         return packet;
377 }
378
379 struct hpsb_packet *hpsb_make_lockpacket(struct hpsb_host *host, nodeid_t node,
380                                          u64 addr, int extcode,
381                                          quadlet_t * data, quadlet_t arg)
382 {
383         struct hpsb_packet *p;
384         u32 length;
385
386         p = hpsb_alloc_packet(8);
387         if (!p)
388                 return NULL;
389
390         p->host = host;
391         p->node_id = node;
392         if (hpsb_get_tlabel(p)) {
393                 hpsb_free_packet(p);
394                 return NULL;
395         }
396
397         switch (extcode) {
398         case EXTCODE_FETCH_ADD:
399         case EXTCODE_LITTLE_ADD:
400                 length = 4;
401                 if (data)
402                         p->data[0] = *data;
403                 break;
404         default:
405                 length = 8;
406                 if (data) {
407                         p->data[0] = arg;
408                         p->data[1] = *data;
409                 }
410                 break;
411         }
412         fill_async_lock(p, addr, extcode, length);
413
414         return p;
415 }
416
417 struct hpsb_packet *hpsb_make_lock64packet(struct hpsb_host *host,
418                                            nodeid_t node, u64 addr, int extcode,
419                                            octlet_t * data, octlet_t arg)
420 {
421         struct hpsb_packet *p;
422         u32 length;
423
424         p = hpsb_alloc_packet(16);
425         if (!p)
426                 return NULL;
427
428         p->host = host;
429         p->node_id = node;
430         if (hpsb_get_tlabel(p)) {
431                 hpsb_free_packet(p);
432                 return NULL;
433         }
434
435         switch (extcode) {
436         case EXTCODE_FETCH_ADD:
437         case EXTCODE_LITTLE_ADD:
438                 length = 8;
439                 if (data) {
440                         p->data[0] = *data >> 32;
441                         p->data[1] = *data & 0xffffffff;
442                 }
443                 break;
444         default:
445                 length = 16;
446                 if (data) {
447                         p->data[0] = arg >> 32;
448                         p->data[1] = arg & 0xffffffff;
449                         p->data[2] = *data >> 32;
450                         p->data[3] = *data & 0xffffffff;
451                 }
452                 break;
453         }
454         fill_async_lock(p, addr, extcode, length);
455
456         return p;
457 }
458
459 struct hpsb_packet *hpsb_make_phypacket(struct hpsb_host *host, quadlet_t data)
460 {
461         struct hpsb_packet *p;
462
463         p = hpsb_alloc_packet(0);
464         if (!p)
465                 return NULL;
466
467         p->host = host;
468         fill_phy_packet(p, data);
469
470         return p;
471 }
472
473 struct hpsb_packet *hpsb_make_isopacket(struct hpsb_host *host,
474                                         int length, int channel,
475                                         int tag, int sync)
476 {
477         struct hpsb_packet *p;
478
479         p = hpsb_alloc_packet(length);
480         if (!p)
481                 return NULL;
482
483         p->host = host;
484         fill_iso_packet(p, length, channel, tag, sync);
485
486         p->generation = get_hpsb_generation(host);
487
488         return p;
489 }
490
491 /*
492  * FIXME - these functions should probably read from / write to user space to
493  * avoid in kernel buffers for user space callers
494  */
495
496 int hpsb_read(struct hpsb_host *host, nodeid_t node, unsigned int generation,
497               u64 addr, quadlet_t * buffer, size_t length)
498 {
499         struct hpsb_packet *packet;
500         int retval = 0;
501
502         if (length == 0)
503                 return -EINVAL;
504
505         BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
506
507         packet = hpsb_make_readpacket(host, node, addr, length);
508
509         if (!packet) {
510                 return -ENOMEM;
511         }
512
513         packet->generation = generation;
514         retval = hpsb_send_packet_and_wait(packet);
515         if (retval < 0)
516                 goto hpsb_read_fail;
517
518         retval = hpsb_packet_success(packet);
519
520         if (retval == 0) {
521                 if (length == 4) {
522                         *buffer = packet->header[3];
523                 } else {
524                         memcpy(buffer, packet->data, length);
525                 }
526         }
527
528       hpsb_read_fail:
529         hpsb_free_tlabel(packet);
530         hpsb_free_packet(packet);
531
532         return retval;
533 }
534
535 int hpsb_write(struct hpsb_host *host, nodeid_t node, unsigned int generation,
536                u64 addr, quadlet_t * buffer, size_t length)
537 {
538         struct hpsb_packet *packet;
539         int retval;
540
541         if (length == 0)
542                 return -EINVAL;
543
544         BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
545
546         packet = hpsb_make_writepacket(host, node, addr, buffer, length);
547
548         if (!packet)
549                 return -ENOMEM;
550
551         packet->generation = generation;
552         retval = hpsb_send_packet_and_wait(packet);
553         if (retval < 0)
554                 goto hpsb_write_fail;
555
556         retval = hpsb_packet_success(packet);
557
558       hpsb_write_fail:
559         hpsb_free_tlabel(packet);
560         hpsb_free_packet(packet);
561
562         return retval;
563 }
564
565 #if 0
566
567 int hpsb_lock(struct hpsb_host *host, nodeid_t node, unsigned int generation,
568               u64 addr, int extcode, quadlet_t * data, quadlet_t arg)
569 {
570         struct hpsb_packet *packet;
571         int retval = 0;
572
573         BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
574
575         packet = hpsb_make_lockpacket(host, node, addr, extcode, data, arg);
576         if (!packet)
577                 return -ENOMEM;
578
579         packet->generation = generation;
580         retval = hpsb_send_packet_and_wait(packet);
581         if (retval < 0)
582                 goto hpsb_lock_fail;
583
584         retval = hpsb_packet_success(packet);
585
586         if (retval == 0) {
587                 *data = packet->data[0];
588         }
589
590       hpsb_lock_fail:
591         hpsb_free_tlabel(packet);
592         hpsb_free_packet(packet);
593
594         return retval;
595 }
596
597 int hpsb_send_gasp(struct hpsb_host *host, int channel, unsigned int generation,
598                    quadlet_t * buffer, size_t length, u32 specifier_id,
599                    unsigned int version)
600 {
601         struct hpsb_packet *packet;
602         int retval = 0;
603         u16 specifier_id_hi = (specifier_id & 0x00ffff00) >> 8;
604         u8 specifier_id_lo = specifier_id & 0xff;
605
606         HPSB_VERBOSE("Send GASP: channel = %d, length = %Zd", channel, length);
607
608         length += 8;
609
610         packet = hpsb_make_streampacket(host, NULL, length, channel, 3, 0);
611         if (!packet)
612                 return -ENOMEM;
613
614         packet->data[0] = cpu_to_be32((host->node_id << 16) | specifier_id_hi);
615         packet->data[1] =
616             cpu_to_be32((specifier_id_lo << 24) | (version & 0x00ffffff));
617
618         memcpy(&(packet->data[2]), buffer, length - 8);
619
620         packet->generation = generation;
621
622         packet->no_waiter = 1;
623
624         retval = hpsb_send_packet(packet);
625         if (retval < 0)
626                 hpsb_free_packet(packet);
627
628         return retval;
629 }
630
631 #endif                          /*  0  */