Commit | Line | Data |
---|---|---|
2504ba9f | 1 | // SPDX-License-Identifier: GPL-2.0-only |
d855497e | 2 | /* |
d855497e MI |
3 | * |
4 | * Copyright (C) 2005 Mike Isely <isely@pobox.com> | |
d855497e MI |
5 | */ |
6 | ||
7 | #include "pvrusb2-ioread.h" | |
8 | #include "pvrusb2-debug.h" | |
9 | #include <linux/errno.h> | |
10 | #include <linux/string.h> | |
27ac792c | 11 | #include <linux/mm.h> |
d855497e MI |
12 | #include <linux/slab.h> |
13 | #include <linux/mutex.h> | |
7c0f6ba6 | 14 | #include <linux/uaccess.h> |
d855497e MI |
15 | |
16 | #define BUFFER_COUNT 32 | |
17 | #define BUFFER_SIZE PAGE_ALIGN(0x4000) | |
18 | ||
19 | struct pvr2_ioread { | |
20 | struct pvr2_stream *stream; | |
21 | char *buffer_storage[BUFFER_COUNT]; | |
22 | char *sync_key_ptr; | |
23 | unsigned int sync_key_len; | |
24 | unsigned int sync_buf_offs; | |
25 | unsigned int sync_state; | |
26 | unsigned int sync_trashed_count; | |
27 | int enabled; // Streaming is on | |
28 | int spigot_open; // OK to pass data to client | |
29 | int stream_running; // Passing data to client now | |
30 | ||
31 | /* State relevant to current buffer being read */ | |
32 | struct pvr2_buffer *c_buf; | |
33 | char *c_data_ptr; | |
34 | unsigned int c_data_len; | |
35 | unsigned int c_data_offs; | |
36 | struct mutex mutex; | |
37 | }; | |
38 | ||
39 | static int pvr2_ioread_init(struct pvr2_ioread *cp) | |
40 | { | |
41 | unsigned int idx; | |
42 | ||
a0fd1cb1 | 43 | cp->stream = NULL; |
d855497e MI |
44 | mutex_init(&cp->mutex); |
45 | ||
46 | for (idx = 0; idx < BUFFER_COUNT; idx++) { | |
47 | cp->buffer_storage[idx] = kmalloc(BUFFER_SIZE,GFP_KERNEL); | |
48 | if (!(cp->buffer_storage[idx])) break; | |
49 | } | |
50 | ||
51 | if (idx < BUFFER_COUNT) { | |
52 | // An allocation appears to have failed | |
53 | for (idx = 0; idx < BUFFER_COUNT; idx++) { | |
54 | if (!(cp->buffer_storage[idx])) continue; | |
55 | kfree(cp->buffer_storage[idx]); | |
56 | } | |
57 | return -ENOMEM; | |
58 | } | |
59 | return 0; | |
60 | } | |
61 | ||
62 | static void pvr2_ioread_done(struct pvr2_ioread *cp) | |
63 | { | |
64 | unsigned int idx; | |
65 | ||
a0fd1cb1 | 66 | pvr2_ioread_setup(cp,NULL); |
d855497e MI |
67 | for (idx = 0; idx < BUFFER_COUNT; idx++) { |
68 | if (!(cp->buffer_storage[idx])) continue; | |
69 | kfree(cp->buffer_storage[idx]); | |
70 | } | |
71 | } | |
72 | ||
73 | struct pvr2_ioread *pvr2_ioread_create(void) | |
74 | { | |
75 | struct pvr2_ioread *cp; | |
ca545f7c | 76 | cp = kzalloc(sizeof(*cp),GFP_KERNEL); |
a0fd1cb1 | 77 | if (!cp) return NULL; |
d855497e | 78 | pvr2_trace(PVR2_TRACE_STRUCT,"pvr2_ioread_create id=%p",cp); |
d855497e MI |
79 | if (pvr2_ioread_init(cp) < 0) { |
80 | kfree(cp); | |
a0fd1cb1 | 81 | return NULL; |
d855497e MI |
82 | } |
83 | return cp; | |
84 | } | |
85 | ||
86 | void pvr2_ioread_destroy(struct pvr2_ioread *cp) | |
87 | { | |
88 | if (!cp) return; | |
89 | pvr2_ioread_done(cp); | |
90 | pvr2_trace(PVR2_TRACE_STRUCT,"pvr2_ioread_destroy id=%p",cp); | |
91 | if (cp->sync_key_ptr) { | |
92 | kfree(cp->sync_key_ptr); | |
a0fd1cb1 | 93 | cp->sync_key_ptr = NULL; |
d855497e MI |
94 | } |
95 | kfree(cp); | |
96 | } | |
97 | ||
98 | void pvr2_ioread_set_sync_key(struct pvr2_ioread *cp, | |
99 | const char *sync_key_ptr, | |
100 | unsigned int sync_key_len) | |
101 | { | |
102 | if (!cp) return; | |
103 | ||
104 | if (!sync_key_ptr) sync_key_len = 0; | |
105 | if ((sync_key_len == cp->sync_key_len) && | |
106 | ((!sync_key_len) || | |
107 | (!memcmp(sync_key_ptr,cp->sync_key_ptr,sync_key_len)))) return; | |
108 | ||
109 | if (sync_key_len != cp->sync_key_len) { | |
110 | if (cp->sync_key_ptr) { | |
111 | kfree(cp->sync_key_ptr); | |
a0fd1cb1 | 112 | cp->sync_key_ptr = NULL; |
d855497e MI |
113 | } |
114 | cp->sync_key_len = 0; | |
115 | if (sync_key_len) { | |
116 | cp->sync_key_ptr = kmalloc(sync_key_len,GFP_KERNEL); | |
117 | if (cp->sync_key_ptr) { | |
118 | cp->sync_key_len = sync_key_len; | |
119 | } | |
120 | } | |
121 | } | |
122 | if (!cp->sync_key_len) return; | |
123 | memcpy(cp->sync_key_ptr,sync_key_ptr,cp->sync_key_len); | |
124 | } | |
125 | ||
126 | static void pvr2_ioread_stop(struct pvr2_ioread *cp) | |
127 | { | |
128 | if (!(cp->enabled)) return; | |
129 | pvr2_trace(PVR2_TRACE_START_STOP, | |
130 | "/*---TRACE_READ---*/ pvr2_ioread_stop id=%p",cp); | |
131 | pvr2_stream_kill(cp->stream); | |
a0fd1cb1 MI |
132 | cp->c_buf = NULL; |
133 | cp->c_data_ptr = NULL; | |
d855497e MI |
134 | cp->c_data_len = 0; |
135 | cp->c_data_offs = 0; | |
136 | cp->enabled = 0; | |
137 | cp->stream_running = 0; | |
138 | cp->spigot_open = 0; | |
139 | if (cp->sync_state) { | |
140 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
141 | "/*---TRACE_READ---*/ sync_state <== 0"); | |
142 | cp->sync_state = 0; | |
143 | } | |
144 | } | |
145 | ||
146 | static int pvr2_ioread_start(struct pvr2_ioread *cp) | |
147 | { | |
148 | int stat; | |
149 | struct pvr2_buffer *bp; | |
150 | if (cp->enabled) return 0; | |
151 | if (!(cp->stream)) return 0; | |
152 | pvr2_trace(PVR2_TRACE_START_STOP, | |
153 | "/*---TRACE_READ---*/ pvr2_ioread_start id=%p",cp); | |
5fa1247a | 154 | while ((bp = pvr2_stream_get_idle_buffer(cp->stream)) != NULL) { |
d855497e MI |
155 | stat = pvr2_buffer_queue(bp); |
156 | if (stat < 0) { | |
157 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
96292c89 | 158 | "/*---TRACE_READ---*/ pvr2_ioread_start id=%p error=%d", |
d855497e MI |
159 | cp,stat); |
160 | pvr2_ioread_stop(cp); | |
161 | return stat; | |
162 | } | |
163 | } | |
164 | cp->enabled = !0; | |
a0fd1cb1 MI |
165 | cp->c_buf = NULL; |
166 | cp->c_data_ptr = NULL; | |
d855497e MI |
167 | cp->c_data_len = 0; |
168 | cp->c_data_offs = 0; | |
169 | cp->stream_running = 0; | |
170 | if (cp->sync_key_len) { | |
171 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
172 | "/*---TRACE_READ---*/ sync_state <== 1"); | |
173 | cp->sync_state = 1; | |
174 | cp->sync_trashed_count = 0; | |
175 | cp->sync_buf_offs = 0; | |
176 | } | |
177 | cp->spigot_open = 0; | |
178 | return 0; | |
179 | } | |
180 | ||
181 | struct pvr2_stream *pvr2_ioread_get_stream(struct pvr2_ioread *cp) | |
182 | { | |
183 | return cp->stream; | |
184 | } | |
185 | ||
186 | int pvr2_ioread_setup(struct pvr2_ioread *cp,struct pvr2_stream *sp) | |
187 | { | |
188 | int ret; | |
189 | unsigned int idx; | |
190 | struct pvr2_buffer *bp; | |
191 | ||
f419edd4 MCC |
192 | mutex_lock(&cp->mutex); |
193 | do { | |
d855497e MI |
194 | if (cp->stream) { |
195 | pvr2_trace(PVR2_TRACE_START_STOP, | |
96292c89 MCC |
196 | "/*---TRACE_READ---*/ pvr2_ioread_setup (tear-down) id=%p", |
197 | cp); | |
d855497e MI |
198 | pvr2_ioread_stop(cp); |
199 | pvr2_stream_kill(cp->stream); | |
e61b6fc5 MI |
200 | if (pvr2_stream_get_buffer_count(cp->stream)) { |
201 | pvr2_stream_set_buffer_count(cp->stream,0); | |
202 | } | |
a0fd1cb1 | 203 | cp->stream = NULL; |
d855497e MI |
204 | } |
205 | if (sp) { | |
206 | pvr2_trace(PVR2_TRACE_START_STOP, | |
96292c89 MCC |
207 | "/*---TRACE_READ---*/ pvr2_ioread_setup (setup) id=%p", |
208 | cp); | |
d855497e MI |
209 | pvr2_stream_kill(sp); |
210 | ret = pvr2_stream_set_buffer_count(sp,BUFFER_COUNT); | |
4c61f678 JL |
211 | if (ret < 0) { |
212 | mutex_unlock(&cp->mutex); | |
213 | return ret; | |
214 | } | |
d855497e MI |
215 | for (idx = 0; idx < BUFFER_COUNT; idx++) { |
216 | bp = pvr2_stream_get_buffer(sp,idx); | |
217 | pvr2_buffer_set_buffer(bp, | |
218 | cp->buffer_storage[idx], | |
219 | BUFFER_SIZE); | |
220 | } | |
221 | cp->stream = sp; | |
222 | } | |
f419edd4 MCC |
223 | } while (0); |
224 | mutex_unlock(&cp->mutex); | |
d855497e MI |
225 | |
226 | return 0; | |
227 | } | |
228 | ||
229 | int pvr2_ioread_set_enabled(struct pvr2_ioread *cp,int fl) | |
230 | { | |
231 | int ret = 0; | |
232 | if ((!fl) == (!(cp->enabled))) return ret; | |
233 | ||
f419edd4 MCC |
234 | mutex_lock(&cp->mutex); |
235 | do { | |
d855497e MI |
236 | if (fl) { |
237 | ret = pvr2_ioread_start(cp); | |
238 | } else { | |
239 | pvr2_ioread_stop(cp); | |
240 | } | |
f419edd4 MCC |
241 | } while (0); |
242 | mutex_unlock(&cp->mutex); | |
d855497e MI |
243 | return ret; |
244 | } | |
245 | ||
07e337ee | 246 | static int pvr2_ioread_get_buffer(struct pvr2_ioread *cp) |
d855497e MI |
247 | { |
248 | int stat; | |
249 | ||
250 | while (cp->c_data_len <= cp->c_data_offs) { | |
251 | if (cp->c_buf) { | |
252 | // Flush out current buffer first. | |
253 | stat = pvr2_buffer_queue(cp->c_buf); | |
254 | if (stat < 0) { | |
255 | // Streaming error... | |
256 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
96292c89 | 257 | "/*---TRACE_READ---*/ pvr2_ioread_read id=%p queue_error=%d", |
d855497e MI |
258 | cp,stat); |
259 | pvr2_ioread_stop(cp); | |
260 | return 0; | |
261 | } | |
a0fd1cb1 MI |
262 | cp->c_buf = NULL; |
263 | cp->c_data_ptr = NULL; | |
d855497e MI |
264 | cp->c_data_len = 0; |
265 | cp->c_data_offs = 0; | |
266 | } | |
267 | // Now get a freshly filled buffer. | |
268 | cp->c_buf = pvr2_stream_get_ready_buffer(cp->stream); | |
269 | if (!cp->c_buf) break; // Nothing ready; done. | |
270 | cp->c_data_len = pvr2_buffer_get_count(cp->c_buf); | |
271 | if (!cp->c_data_len) { | |
272 | // Nothing transferred. Was there an error? | |
273 | stat = pvr2_buffer_get_status(cp->c_buf); | |
274 | if (stat < 0) { | |
275 | // Streaming error... | |
276 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
96292c89 | 277 | "/*---TRACE_READ---*/ pvr2_ioread_read id=%p buffer_error=%d", |
d855497e MI |
278 | cp,stat); |
279 | pvr2_ioread_stop(cp); | |
280 | // Give up. | |
281 | return 0; | |
282 | } | |
283 | // Start over... | |
284 | continue; | |
285 | } | |
286 | cp->c_data_offs = 0; | |
287 | cp->c_data_ptr = cp->buffer_storage[ | |
288 | pvr2_buffer_get_id(cp->c_buf)]; | |
289 | } | |
290 | return !0; | |
291 | } | |
292 | ||
07e337ee | 293 | static void pvr2_ioread_filter(struct pvr2_ioread *cp) |
d855497e MI |
294 | { |
295 | unsigned int idx; | |
296 | if (!cp->enabled) return; | |
297 | if (cp->sync_state != 1) return; | |
298 | ||
299 | // Search the stream for our synchronization key. This is made | |
300 | // complicated by the fact that in order to be honest with | |
301 | // ourselves here we must search across buffer boundaries... | |
f419edd4 MCC |
302 | mutex_lock(&cp->mutex); |
303 | while (1) { | |
d855497e MI |
304 | // Ensure we have a buffer |
305 | if (!pvr2_ioread_get_buffer(cp)) break; | |
306 | if (!cp->c_data_len) break; | |
307 | ||
308 | // Now walk the buffer contents until we match the key or | |
309 | // run out of buffer data. | |
310 | for (idx = cp->c_data_offs; idx < cp->c_data_len; idx++) { | |
311 | if (cp->sync_buf_offs >= cp->sync_key_len) break; | |
312 | if (cp->c_data_ptr[idx] == | |
313 | cp->sync_key_ptr[cp->sync_buf_offs]) { | |
314 | // Found the next key byte | |
315 | (cp->sync_buf_offs)++; | |
316 | } else { | |
317 | // Whoops, mismatched. Start key over... | |
318 | cp->sync_buf_offs = 0; | |
319 | } | |
320 | } | |
321 | ||
322 | // Consume what we've walked through | |
323 | cp->c_data_offs += idx; | |
324 | cp->sync_trashed_count += idx; | |
325 | ||
326 | // If we've found the key, then update state and get out. | |
327 | if (cp->sync_buf_offs >= cp->sync_key_len) { | |
328 | cp->sync_trashed_count -= cp->sync_key_len; | |
329 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
96292c89 | 330 | "/*---TRACE_READ---*/ sync_state <== 2 (skipped %u bytes)", |
d855497e MI |
331 | cp->sync_trashed_count); |
332 | cp->sync_state = 2; | |
333 | cp->sync_buf_offs = 0; | |
334 | break; | |
335 | } | |
336 | ||
337 | if (cp->c_data_offs < cp->c_data_len) { | |
338 | // Sanity check - should NEVER get here | |
339 | pvr2_trace(PVR2_TRACE_ERROR_LEGS, | |
96292c89 | 340 | "ERROR: pvr2_ioread filter sync problem len=%u offs=%u", |
d855497e MI |
341 | cp->c_data_len,cp->c_data_offs); |
342 | // Get out so we don't get stuck in an infinite | |
343 | // loop. | |
344 | break; | |
345 | } | |
346 | ||
347 | continue; // (for clarity) | |
f419edd4 MCC |
348 | } |
349 | mutex_unlock(&cp->mutex); | |
d855497e MI |
350 | } |
351 | ||
352 | int pvr2_ioread_avail(struct pvr2_ioread *cp) | |
353 | { | |
354 | int ret; | |
355 | if (!(cp->enabled)) { | |
356 | // Stream is not enabled; so this is an I/O error | |
357 | return -EIO; | |
358 | } | |
359 | ||
360 | if (cp->sync_state == 1) { | |
361 | pvr2_ioread_filter(cp); | |
362 | if (cp->sync_state == 1) return -EAGAIN; | |
363 | } | |
364 | ||
365 | ret = 0; | |
366 | if (cp->stream_running) { | |
367 | if (!pvr2_stream_get_ready_count(cp->stream)) { | |
368 | // No data available at all right now. | |
369 | ret = -EAGAIN; | |
370 | } | |
371 | } else { | |
372 | if (pvr2_stream_get_ready_count(cp->stream) < BUFFER_COUNT/2) { | |
373 | // Haven't buffered up enough yet; try again later | |
374 | ret = -EAGAIN; | |
375 | } | |
376 | } | |
377 | ||
378 | if ((!(cp->spigot_open)) != (!(ret == 0))) { | |
379 | cp->spigot_open = (ret == 0); | |
380 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
381 | "/*---TRACE_READ---*/ data is %s", | |
382 | cp->spigot_open ? "available" : "pending"); | |
383 | } | |
384 | ||
385 | return ret; | |
386 | } | |
387 | ||
388 | int pvr2_ioread_read(struct pvr2_ioread *cp,void __user *buf,unsigned int cnt) | |
389 | { | |
390 | unsigned int copied_cnt; | |
391 | unsigned int bcnt; | |
392 | const char *src; | |
393 | int stat; | |
394 | int ret = 0; | |
395 | unsigned int req_cnt = cnt; | |
396 | ||
397 | if (!cnt) { | |
398 | pvr2_trace(PVR2_TRACE_TRAP, | |
96292c89 MCC |
399 | "/*---TRACE_READ---*/ pvr2_ioread_read id=%p ZERO Request? Returning zero.", |
400 | cp); | |
d855497e MI |
401 | return 0; |
402 | } | |
403 | ||
404 | stat = pvr2_ioread_avail(cp); | |
405 | if (stat < 0) return stat; | |
406 | ||
407 | cp->stream_running = !0; | |
408 | ||
f419edd4 MCC |
409 | mutex_lock(&cp->mutex); |
410 | do { | |
d855497e MI |
411 | |
412 | // Suck data out of the buffers and copy to the user | |
413 | copied_cnt = 0; | |
414 | if (!buf) cnt = 0; | |
415 | while (1) { | |
416 | if (!pvr2_ioread_get_buffer(cp)) { | |
417 | ret = -EIO; | |
418 | break; | |
419 | } | |
420 | ||
421 | if (!cnt) break; | |
422 | ||
423 | if (cp->sync_state == 2) { | |
424 | // We're repeating the sync key data into | |
425 | // the stream. | |
426 | src = cp->sync_key_ptr + cp->sync_buf_offs; | |
427 | bcnt = cp->sync_key_len - cp->sync_buf_offs; | |
428 | } else { | |
429 | // Normal buffer copy | |
430 | src = cp->c_data_ptr + cp->c_data_offs; | |
431 | bcnt = cp->c_data_len - cp->c_data_offs; | |
432 | } | |
433 | ||
434 | if (!bcnt) break; | |
435 | ||
436 | // Don't run past user's buffer | |
437 | if (bcnt > cnt) bcnt = cnt; | |
438 | ||
439 | if (copy_to_user(buf,src,bcnt)) { | |
440 | // User supplied a bad pointer? | |
441 | // Give up - this *will* cause data | |
442 | // to be lost. | |
443 | ret = -EFAULT; | |
444 | break; | |
445 | } | |
446 | cnt -= bcnt; | |
447 | buf += bcnt; | |
448 | copied_cnt += bcnt; | |
449 | ||
450 | if (cp->sync_state == 2) { | |
451 | // Update offset inside sync key that we're | |
452 | // repeating back out. | |
453 | cp->sync_buf_offs += bcnt; | |
454 | if (cp->sync_buf_offs >= cp->sync_key_len) { | |
455 | // Consumed entire key; switch mode | |
456 | // to normal. | |
457 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
96292c89 | 458 | "/*---TRACE_READ---*/ sync_state <== 0"); |
d855497e MI |
459 | cp->sync_state = 0; |
460 | } | |
461 | } else { | |
462 | // Update buffer offset. | |
463 | cp->c_data_offs += bcnt; | |
464 | } | |
465 | } | |
466 | ||
f419edd4 MCC |
467 | } while (0); |
468 | mutex_unlock(&cp->mutex); | |
d855497e MI |
469 | |
470 | if (!ret) { | |
471 | if (copied_cnt) { | |
472 | // If anything was copied, return that count | |
473 | ret = copied_cnt; | |
474 | } else { | |
475 | // Nothing copied; suggest to caller that another | |
476 | // attempt should be tried again later | |
477 | ret = -EAGAIN; | |
478 | } | |
479 | } | |
480 | ||
481 | pvr2_trace(PVR2_TRACE_DATA_FLOW, | |
96292c89 | 482 | "/*---TRACE_READ---*/ pvr2_ioread_read id=%p request=%d result=%d", |
d855497e MI |
483 | cp,req_cnt,ret); |
484 | return ret; | |
485 | } |