1 /*
2 * $Id: video-buf.c,v 1.17 2004/12/10 12:33:40 kraxel Exp $
3 *
4 * generic helper functions for video4linux capture buffers, to handle
5 * memory management and PCI DMA. Right now bttv + saa7134 use it.
6 *
7 * The functions expect the hardware being able to scatter gatter
8 * (i.e. the buffers are not linear in physical memory, but fragmented
9 * into PAGE_SIZE chunks). They also assume the driver does not need
10 * to touch the video data (thus it is probably not useful for USB 1.1
11 * as data often must be uncompressed by the drivers).
12 *
13 * (c) 2001-2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
14 *
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
19 */
20
21 #include <linux/init.h>
22 #include <linux/module.h>
23 #include <linux/moduleparam.h>
24 #include <linux/vmalloc.h>
25 #include <linux/pagemap.h>
26 #include <linux/slab.h>
27 #include <linux/pci.h>
28 #include <linux/interrupt.h>
29 #include <asm/page.h>
30 #include <asm/pgtable.h>
31
32 #include <media/video-buf.h>
33
34 #define MAGIC_DMABUF 0x19721112
35 #define MAGIC_BUFFER 0x20040302
36 #define MAGIC_CHECK(is,should) if (unlikely((is) != (should))) \
37 { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
38
39 static int debug = 0;
40 module_param(debug, int, 0644);
41
42 MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
43 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
44 MODULE_LICENSE("GPL");
45
46 #define dprintk(level, fmt, arg...) if (debug >= level) \
47 printk(KERN_DEBUG "vbuf: " fmt , ## arg)
48
49 struct scatterlist*
50 videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
51 {
52 struct scatterlist *sglist;
53 struct page *pg;
54 int i;
55
56 sglist = kmalloc(sizeof(struct scatterlist)*nr_pages, GFP_KERNEL);
57 if (NULL == sglist)
58 return NULL;
59 memset(sglist,0,sizeof(struct scatterlist)*nr_pages);
60 for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
61 pg = vmalloc_to_page(virt);
62 if (NULL == pg)
63 goto err;
64 if (PageHighMem(pg))
65 BUG();
66 sglist[i].page = pg;
67 sglist[i].length = PAGE_SIZE;
68 }
69 return sglist;
70
71 err:
72 kfree(sglist);
73 return NULL;
74 }
75
76 struct scatterlist*
77 videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
78 {
79 struct scatterlist *sglist;
80 int i = 0;
81
82 if (NULL == pages[0])
83 return NULL;
84 sglist = kmalloc(sizeof(*sglist) * nr_pages, GFP_KERNEL);
85 if (NULL == sglist)
86 return NULL;
87 memset(sglist, 0, sizeof(*sglist) * nr_pages);
88
89 if (NULL == pages[0])
90 goto nopage;
91 if (PageHighMem(pages[0]))
92 /* DMA to highmem pages might not work */
93 goto highmem;
94 sglist[0].page = pages[0];
95 sglist[0].offset = offset;
96 sglist[0].length = PAGE_SIZE - offset;
97 for (i = 1; i < nr_pages; i++) {
98 if (NULL == pages[i])
99 goto nopage;
100 if (PageHighMem(pages[i]))
101 goto highmem;
102 sglist[i].page = pages[i];
103 sglist[i].length = PAGE_SIZE;
104 }
105 return sglist;
106
107 nopage:
108 dprintk(2,"sgl: oops - no page\n");
109 kfree(sglist);
110 return NULL;
111
112 highmem:
113 dprintk(2,"sgl: oops - highmem page\n");
114 kfree(sglist);
115 return NULL;
116 }
117
118 /* --------------------------------------------------------------------- */
119
120 void videobuf_dma_init(struct videobuf_dmabuf *dma)
121 {
122 memset(dma,0,sizeof(*dma));
123 dma->magic = MAGIC_DMABUF;
124 }
125
126 int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
127 unsigned long data, unsigned long size)
128 {
129 unsigned long first,last;
130 int err, rw = 0;
131
132 dma->direction = direction;
133 switch (dma->direction) {
134 case PCI_DMA_FROMDEVICE: rw = READ; break;
135 case PCI_DMA_TODEVICE: rw = WRITE; break;
136 default: BUG();
137 }
138
139 first = (data & PAGE_MASK) >> PAGE_SHIFT;
140 last = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
141 dma->offset = data & ~PAGE_MASK;
142 dma->nr_pages = last-first+1;
143 dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
144 GFP_KERNEL);
145 if (NULL == dma->pages)
146 return -ENOMEM;
147 dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
148 data,size,dma->nr_pages);
149
150 down_read(¤t->mm->mmap_sem);
151 err = get_user_pages(current,current->mm,
152 data & PAGE_MASK, dma->nr_pages,
153 rw == READ, 1, /* force */
154 dma->pages, NULL);
155 up_read(¤t->mm->mmap_sem);
156 if (err != dma->nr_pages) {
157 dma->nr_pages = (err >= 0) ? err : 0;
158 dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
159 return err < 0 ? err : -EINVAL;
160 }
161 return 0;
162 }
163
164 int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
165 int nr_pages)
166 {
167 dprintk(1,"init kernel [%d pages]\n",nr_pages);
168 dma->direction = direction;
169 dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
170 if (NULL == dma->vmalloc) {
171 dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
172 return -ENOMEM;
173 }
174 memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
175 dma->nr_pages = nr_pages;
176 return 0;
177 }
178
179 int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
180 dma_addr_t addr, int nr_pages)
181 {
182 dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
183 nr_pages,(unsigned long)addr);
184 dma->direction = direction;
185 if (0 == addr)
186 return -EINVAL;
187
188 dma->bus_addr = addr;
189 dma->nr_pages = nr_pages;
190 return 0;
191 }
192
193 int videobuf_dma_pci_map(struct pci_dev *dev, struct videobuf_dmabuf *dma)
194 {
195 MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
196 BUG_ON(0 == dma->nr_pages);
197
198 if (dma->pages) {
199 dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
200 dma->offset);
201 }
202 if (dma->vmalloc) {
203 dma->sglist = videobuf_vmalloc_to_sg
204 (dma->vmalloc,dma->nr_pages);
205 }
206 if (dma->bus_addr) {
207 dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
208 if (NULL != dma->sglist) {
209 dma->sglen = 1;
210 sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
211 dma->sglist[0].offset = dma->bus_addr & ~PAGE_MASK;
212 sg_dma_len(&dma->sglist[0]) = dma->nr_pages * PAGE_SIZE;
213 }
214 }
215 if (NULL == dma->sglist) {
216 dprintk(1,"scatterlist is NULL\n");
217 return -ENOMEM;
218 }
219
220 if (!dma->bus_addr)
221 dma->sglen = pci_map_sg(dev,dma->sglist,dma->nr_pages,
222 dma->direction);
223 return 0;
224 }
225
226 int videobuf_dma_pci_sync(struct pci_dev *dev, struct videobuf_dmabuf *dma)
227 {
228 MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
229 BUG_ON(!dma->sglen);
230
231 if (!dma->bus_addr)
232 pci_dma_sync_sg_for_cpu(dev,dma->sglist,dma->nr_pages,dma->direction);
233 return 0;
234 }
235
236 int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma)
237 {
238 MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
239 if (!dma->sglen)
240 return 0;
241
242 if (!dma->bus_addr)
243 pci_unmap_sg(dev,dma->sglist,dma->nr_pages,dma->direction);
244 kfree(dma->sglist);
245 dma->sglist = NULL;
246 dma->sglen = 0;
247 return 0;
248 }
249
250 int videobuf_dma_free(struct videobuf_dmabuf *dma)
251 {
252 MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
253 BUG_ON(dma->sglen);
254
255 if (dma->pages) {
256 int i;
257 for (i=0; i < dma->nr_pages; i++)
258 page_cache_release(dma->pages[i]);
259 kfree(dma->pages);
260 dma->pages = NULL;
261 }
262 if (dma->vmalloc) {
263 vfree(dma->vmalloc);
264 dma->vmalloc = NULL;
265 }
266 if (dma->bus_addr) {
267 dma->bus_addr = 0;
268 }
269 dma->direction = PCI_DMA_NONE;
270 return 0;
271 }
272
273 /* --------------------------------------------------------------------- */
274
275 void* videobuf_alloc(unsigned int size)
276 {
277 struct videobuf_buffer *vb;
278
279 vb = kmalloc(size,GFP_KERNEL);
280 if (NULL != vb) {
281 memset(vb,0,size);
282 videobuf_dma_init(&vb->dma);
283 init_waitqueue_head(&vb->done);
284 vb->magic = MAGIC_BUFFER;
285 }
286 return vb;
287 }
288
289 int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
290 {
291 int retval = 0;
292 DECLARE_WAITQUEUE(wait, current);
293
294 MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
295 add_wait_queue(&vb->done, &wait);
296 while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
297 if (non_blocking) {
298 retval = -EAGAIN;
299 break;
300 }
301 set_current_state(intr ? TASK_INTERRUPTIBLE
302 : TASK_UNINTERRUPTIBLE);
303 if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
304 schedule();
305 set_current_state(TASK_RUNNING);
306 if (intr && signal_pending(current)) {
307 dprintk(1,"buffer waiton: -EINTR\n");
308 retval = -EINTR;
309 break;
310 }
311 }
312 remove_wait_queue(&vb->done, &wait);
313 return retval;
314 }
315
316 int
317 videobuf_iolock(struct pci_dev *pci, struct videobuf_buffer *vb,
318 struct v4l2_framebuffer *fbuf)
319 {
320 int err,pages;
321 dma_addr_t bus;
322
323 MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
324 switch (vb->memory) {
325 case V4L2_MEMORY_MMAP:
326 case V4L2_MEMORY_USERPTR:
327 if (0 == vb->baddr) {
328 /* no userspace addr -- kernel bounce buffer */
329 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
330 err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
331 pages);
332 if (0 != err)
333 return err;
334 } else {
335 /* dma directly to userspace */
336 err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
337 vb->baddr,vb->bsize);
338 if (0 != err)
339 return err;
340 }
341 break;
342 case V4L2_MEMORY_OVERLAY:
343 if (NULL == fbuf)
344 return -EINVAL;
345 /* FIXME: need sanity checks for vb->boff */
346 bus = (dma_addr_t)fbuf->base + vb->boff;
347 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
348 err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
349 bus, pages);
350 if (0 != err)
351 return err;
352 break;
353 default:
354 BUG();
355 }
356 err = videobuf_dma_pci_map(pci,&vb->dma);
357 if (0 != err)
358 return err;
359
360 return 0;
361 }
362
363 /* --------------------------------------------------------------------- */
364
365 void videobuf_queue_init(struct videobuf_queue* q,
366 struct videobuf_queue_ops *ops,
367 struct pci_dev *pci,
368 spinlock_t *irqlock,
369 enum v4l2_buf_type type,
370 enum v4l2_field field,
371 unsigned int msize,
372 void *priv)
373 {
374 memset(q,0,sizeof(*q));
375 q->irqlock = irqlock;
376 q->pci = pci;
377 q->type = type;
378 q->field = field;
379 q->msize = msize;
380 q->ops = ops;
381 q->priv_data = priv;
382
383 init_MUTEX(&q->lock);
384 INIT_LIST_HEAD(&q->stream);
385 }
386
387 int
388 videobuf_queue_is_busy(struct videobuf_queue *q)
389 {
390 int i;
391
392 if (q->streaming) {
393 dprintk(1,"busy: streaming active\n");
394 return 1;
395 }
396 if (q->reading) {
397 dprintk(1,"busy: pending read #1\n");
398 return 1;
399 }
400 if (q->read_buf) {
401 dprintk(1,"busy: pending read #2\n");
402 return 1;
403 }
404 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
405 if (NULL == q->bufs[i])
406 continue;
407 if (q->bufs[i]->map) {
408 dprintk(1,"busy: buffer #%d mapped\n",i);
409 return 1;
410 }
411 if (q->bufs[i]->state == STATE_QUEUED) {
412 dprintk(1,"busy: buffer #%d queued\n",i);
413 return 1;
414 }
415 if (q->bufs[i]->state == STATE_ACTIVE) {
416 dprintk(1,"busy: buffer #%d avtive\n",i);
417 return 1;
418 }
419 }
420 return 0;
421 }
422
423 void
424 videobuf_queue_cancel(struct videobuf_queue *q)
425 {
426 unsigned long flags;
427 int i;
428
429 /* remove queued buffers from list */
430 spin_lock_irqsave(q->irqlock,flags);
431 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
432 if (NULL == q->bufs[i])
433 continue;
434 if (q->bufs[i]->state == STATE_QUEUED) {
435 list_del(&q->bufs[i]->queue);
436 q->bufs[i]->state = STATE_ERROR;
437 }
438 }
439 spin_unlock_irqrestore(q->irqlock,flags);
440
441 /* free all buffers + clear queue */
442 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
443 if (NULL == q->bufs[i])
444 continue;
445 q->ops->buf_release(q,q->bufs[i]);
446 }
447 INIT_LIST_HEAD(&q->stream);
448 }
449
450 /* --------------------------------------------------------------------- */
451
452 enum v4l2_field
453 videobuf_next_field(struct videobuf_queue *q)
454 {
455 enum v4l2_field field = q->field;
456
457 BUG_ON(V4L2_FIELD_ANY == field);
458
459 if (V4L2_FIELD_ALTERNATE == field) {
460 if (V4L2_FIELD_TOP == q->last) {
461 field = V4L2_FIELD_BOTTOM;
462 q->last = V4L2_FIELD_BOTTOM;
463 } else {
464 field = V4L2_FIELD_TOP;
465 q->last = V4L2_FIELD_TOP;
466 }
467 }
468 return field;
469 }
470
471 void
472 videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
473 enum v4l2_buf_type type)
474 {
475 MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
476
477 b->index = vb->i;
478 b->type = type;
479
480 b->memory = vb->memory;
481 switch (b->memory) {
482 case V4L2_MEMORY_MMAP:
483 b->m.offset = vb->boff;
484 b->length = vb->bsize;
485 break;
486 case V4L2_MEMORY_USERPTR:
487 b->m.userptr = vb->baddr;
488 b->length = vb->bsize;
489 break;
490 case V4L2_MEMORY_OVERLAY:
491 b->m.offset = vb->boff;
492 break;
493 }
494
495 b->flags = 0;
496 if (vb->map)
497 b->flags |= V4L2_BUF_FLAG_MAPPED;
498
499 switch (vb->state) {
500 case STATE_PREPARED:
501 case STATE_QUEUED:
502 case STATE_ACTIVE:
503 b->flags |= V4L2_BUF_FLAG_QUEUED;
504 break;
505 case STATE_DONE:
506 case STATE_ERROR:
507 b->flags |= V4L2_BUF_FLAG_DONE;
508 break;
509 case STATE_NEEDS_INIT:
510 case STATE_IDLE:
511 /* nothing */
512 break;
513 }
514
515 if (vb->input != UNSET) {
516 b->flags |= V4L2_BUF_FLAG_INPUT;
517 b->input = vb->input;
518 }
519
520 b->field = vb->field;
521 b->timestamp = vb->ts;
522 b->bytesused = vb->size;
523 b->sequence = vb->field_count >> 1;
524 }
525
526 int
527 videobuf_reqbufs(struct videobuf_queue *q,
528 struct v4l2_requestbuffers *req)
529 {
530 unsigned int size,count;
531 int retval;
532
533 if (req->type != q->type)
534 return -EINVAL;
535 if (req->count < 1)
536 return -EINVAL;
537 if (req->memory != V4L2_MEMORY_MMAP &&
538 req->memory != V4L2_MEMORY_USERPTR &&
539 req->memory != V4L2_MEMORY_OVERLAY)
540 return -EINVAL;
541
542 if (q->streaming)
543 return -EBUSY;
544 if (!list_empty(&q->stream))
545 return -EBUSY;
546
547 down(&q->lock);
548 count = req->count;
549 if (count > VIDEO_MAX_FRAME)
550 count = VIDEO_MAX_FRAME;
551 size = 0;
552 q->ops->buf_setup(q,&count,&size);
553 size = PAGE_ALIGN(size);
554 dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
555 count, size, (count*size)>>PAGE_SHIFT);
556
557 retval = videobuf_mmap_setup(q,count,size,req->memory);
558 if (retval < 0)
559 goto done;
560
561 req->count = count;
562
563 done:
564 up(&q->lock);
565 return retval;
566 }
567
568 int
569 videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
570 {
571 if (unlikely(b->type != q->type))
572 return -EINVAL;
573 if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME))
574 return -EINVAL;
575 if (unlikely(NULL == q->bufs[b->index]))
576 return -EINVAL;
577 videobuf_status(b,q->bufs[b->index],q->type);
578 return 0;
579 }
580
581 int
582 videobuf_qbuf(struct videobuf_queue *q,
583 struct v4l2_buffer *b)
584 {
585 struct videobuf_buffer *buf;
586 enum v4l2_field field;
587 unsigned long flags;
588 int retval;
589
590 down(&q->lock);
591 retval = -EBUSY;
592 if (q->reading)
593 goto done;
594 retval = -EINVAL;
595 if (b->type != q->type)
596 goto done;
597 if (b->index < 0 || b->index >= VIDEO_MAX_FRAME)
598 goto done;
599 buf = q->bufs[b->index];
600 if (NULL == buf)
601 goto done;
602 MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
603 if (buf->memory != b->memory)
604 goto done;
605 if (buf->state == STATE_QUEUED ||
606 buf->state == STATE_ACTIVE)
607 goto done;
608
609 if (b->flags & V4L2_BUF_FLAG_INPUT) {
610 if (b->input >= q->inputs)
611 goto done;
612 buf->input = b->input;
613 } else {
614 buf->input = UNSET;
615 }
616
617 switch (b->memory) {
618 case V4L2_MEMORY_MMAP:
619 if (0 == buf->baddr)
620 goto done;
621 break;
622 case V4L2_MEMORY_USERPTR:
623 if (b->length < buf->bsize)
624 goto done;
625 if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
626 q->ops->buf_release(q,buf);
627 buf->baddr = b->m.userptr;
628 break;
629 case V4L2_MEMORY_OVERLAY:
630 buf->boff = b->m.offset;
631 break;
632 default:
633 goto done;
634 }
635
636 field = videobuf_next_field(q);
637 retval = q->ops->buf_prepare(q,buf,field);
638 if (0 != retval)
639 goto done;
640
641 list_add_tail(&buf->stream,&q->stream);
642 if (q->streaming) {
643 spin_lock_irqsave(q->irqlock,flags);
644 q->ops->buf_queue(q,buf);
645 spin_unlock_irqrestore(q->irqlock,flags);
646 }
647 retval = 0;
648
649 done:
650 up(&q->lock);
651 return retval;
652 }
653
654 int
655 videobuf_dqbuf(struct videobuf_queue *q,
656 struct v4l2_buffer *b, int nonblocking)
657 {
658 struct videobuf_buffer *buf;
659 int retval;
660
661 down(&q->lock);
662 retval = -EBUSY;
663 if (q->reading)
664 goto done;
665 retval = -EINVAL;
666 if (b->type != q->type)
667 goto done;
668 if (list_empty(&q->stream))
669 goto done;
670 buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
671 retval = videobuf_waiton(buf, nonblocking, 1);
672 if (retval < 0)
673 goto done;
674 switch (buf->state) {
675 case STATE_ERROR:
676 retval = -EIO;
677 /* fall through */
678 case STATE_DONE:
679 videobuf_dma_pci_sync(q->pci,&buf->dma);
680 buf->state = STATE_IDLE;
681 break;
682 default:
683 retval = -EINVAL;
684 goto done;
685 }
686 list_del(&buf->stream);
687 memset(b,0,sizeof(*b));
688 videobuf_status(b,buf,q->type);
689
690 done:
691 up(&q->lock);
692 return retval;
693 }
694
695 int videobuf_streamon(struct videobuf_queue *q)
696 {
697 struct videobuf_buffer *buf;
698 struct list_head *list;
699 unsigned long flags;
700 int retval;
701
702 down(&q->lock);
703 retval = -EBUSY;
704 if (q->reading)
705 goto done;
706 retval = 0;
707 if (q->streaming)
708 goto done;
709 q->streaming = 1;
710 spin_lock_irqsave(q->irqlock,flags);
711 list_for_each(list,&q->stream) {
712 buf = list_entry(list, struct videobuf_buffer, stream);
713 if (buf->state == STATE_PREPARED)
714 q->ops->buf_queue(q,buf);
715 }
716 spin_unlock_irqrestore(q->irqlock,flags);
717
718 done:
719 up(&q->lock);
720 return retval;
721 }
722
723 int videobuf_streamoff(struct videobuf_queue *q)
724 {
725 int retval = -EINVAL;
726
727 down(&q->lock);
728 if (!q->streaming)
729 goto done;
730 videobuf_queue_cancel(q);
731 q->streaming = 0;
732 retval = 0;
733
734 done:
735 up(&q->lock);
736 return retval;
737 }
738
739 static ssize_t
740 videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
741 size_t count, loff_t *ppos)
742 {
743 enum v4l2_field field;
744 unsigned long flags;
745 int retval;
746
747 /* setup stuff */
748 retval = -ENOMEM;
749 q->read_buf = videobuf_alloc(q->msize);
750 if (NULL == q->read_buf)
751 goto done;
752
753 q->read_buf->memory = V4L2_MEMORY_USERPTR;
754 q->read_buf->baddr = (unsigned long)data;
755 q->read_buf->bsize = count;
756 field = videobuf_next_field(q);
757 retval = q->ops->buf_prepare(q,q->read_buf,field);
758 if (0 != retval)
759 goto done;
760
761 /* start capture & wait */
762 spin_lock_irqsave(q->irqlock,flags);
763 q->ops->buf_queue(q,q->read_buf);
764 spin_unlock_irqrestore(q->irqlock,flags);
765 retval = videobuf_waiton(q->read_buf,0,0);
766 if (0 == retval) {
767 videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
768 if (STATE_ERROR == q->read_buf->state)
769 retval = -EIO;
770 else
771 retval = q->read_buf->size;
772 }
773
774 done:
775 /* cleanup */
776 q->ops->buf_release(q,q->read_buf);
777 kfree(q->read_buf);
778 q->read_buf = NULL;
779 return retval;
780 }
781
782 ssize_t videobuf_read_one(struct videobuf_queue *q,
783 char __user *data, size_t count, loff_t *ppos,
784 int nonblocking)
785 {
786 enum v4l2_field field;
787 unsigned long flags;
788 unsigned size, nbufs, bytes;
789 int retval;
790
791 down(&q->lock);
792
793 nbufs = 1; size = 0;
794 q->ops->buf_setup(q,&nbufs,&size);
795 if (NULL == q->read_buf &&
796 count >= size &&
797 !nonblocking) {
798 retval = videobuf_read_zerocopy(q,data,count,ppos);
799 if (retval >= 0 || retval == -EIO)
800 /* ok, all done */
801 goto done;
802 /* fallback to kernel bounce buffer on failures */
803 }
804
805 if (NULL == q->read_buf) {
806 /* need to capture a new frame */
807 retval = -ENOMEM;
808 q->read_buf = videobuf_alloc(q->msize);
809 if (NULL == q->read_buf)
810 goto done;
811 q->read_buf->memory = V4L2_MEMORY_USERPTR;
812 field = videobuf_next_field(q);
813 retval = q->ops->buf_prepare(q,q->read_buf,field);
814 if (0 != retval)
815 goto done;
816 spin_lock_irqsave(q->irqlock,flags);
817 q->ops->buf_queue(q,q->read_buf);
818 spin_unlock_irqrestore(q->irqlock,flags);
819 q->read_off = 0;
820 }
821
822 /* wait until capture is done */
823 retval = videobuf_waiton(q->read_buf, nonblocking, 1);
824 if (0 != retval)
825 goto done;
826 videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
827
828 if (STATE_ERROR == q->read_buf->state) {
829 /* catch I/O errors */
830 q->ops->buf_release(q,q->read_buf);
831 kfree(q->read_buf);
832 q->read_buf = NULL;
833 retval = -EIO;
834 goto done;
835 }
836
837 /* copy to userspace */
838 bytes = count;
839 if (bytes > q->read_buf->size - q->read_off)
840 bytes = q->read_buf->size - q->read_off;
841 retval = -EFAULT;
842 if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
843 goto done;
844
845 retval = bytes;
846 q->read_off += bytes;
847 if (q->read_off == q->read_buf->size) {
848 /* all data copied, cleanup */
849 q->ops->buf_release(q,q->read_buf);
850 kfree(q->read_buf);
851 q->read_buf = NULL;
852 }
853
854 done:
855 up(&q->lock);
856 return retval;
857 }
858
859 int videobuf_read_start(struct videobuf_queue *q)
860 {
861 enum v4l2_field field;
862 unsigned long flags;
863 int count = 0, size = 0;
864 int err, i;
865
866 q->ops->buf_setup(q,&count,&size);
867 if (count < 2)
868 count = 2;
869 if (count > VIDEO_MAX_FRAME)
870 count = VIDEO_MAX_FRAME;
871 size = PAGE_ALIGN(size);
872
873 err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
874 if (err)
875 return err;
876 for (i = 0; i < count; i++) {
877 field = videobuf_next_field(q);
878 err = q->ops->buf_prepare(q,q->bufs[i],field);
879 if (err)
880 return err;
881 list_add_tail(&q->bufs[i]->stream, &q->stream);
882 }
883 spin_lock_irqsave(q->irqlock,flags);
884 for (i = 0; i < count; i++)
885 q->ops->buf_queue(q,q->bufs[i]);
886 spin_unlock_irqrestore(q->irqlock,flags);
887 q->reading = 1;
888 return 0;
889 }
890
891 void videobuf_read_stop(struct videobuf_queue *q)
892 {
893 int i;
894
895 videobuf_queue_cancel(q);
896 videobuf_mmap_free(q);
897 INIT_LIST_HEAD(&q->stream);
898 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
899 if (NULL == q->bufs[i])
900 continue;
901 kfree(q->bufs[i]);
902 q->bufs[i] = NULL;
903 }
904 q->read_buf = NULL;
905 q->reading = 0;
906 }
907
908 ssize_t videobuf_read_stream(struct videobuf_queue *q,
909 char __user *data, size_t count, loff_t *ppos,
910 int vbihack, int nonblocking)
911 {
912 unsigned int *fc, bytes;
913 int err, retval;
914 unsigned long flags;
915
916 dprintk(2,"%s\n",__FUNCTION__);
917 down(&q->lock);
918 retval = -EBUSY;
919 if (q->streaming)
920 goto done;
921 if (!q->reading) {
922 retval = videobuf_read_start(q);
923 if (retval < 0)
924 goto done;
925 }
926
927 retval = 0;
928 while (count > 0) {
929 /* get / wait for data */
930 if (NULL == q->read_buf) {
931 q->read_buf = list_entry(q->stream.next,
932 struct videobuf_buffer,
933 stream);
934 list_del(&q->read_buf->stream);
935 q->read_off = 0;
936 }
937 err = videobuf_waiton(q->read_buf, nonblocking, 1);
938 if (err < 0) {
939 if (0 == retval)
940 retval = err;
941 break;
942 }
943
944 if (q->read_buf->state == STATE_DONE) {
945 if (vbihack) {
946 /* dirty, undocumented hack -- pass the frame counter
947 * within the last four bytes of each vbi data block.
948 * We need that one to maintain backward compatibility
949 * to all vbi decoding software out there ... */
950 fc = (unsigned int*)q->read_buf->dma.vmalloc;
951 fc += (q->read_buf->size>>2) -1;
952 *fc = q->read_buf->field_count >> 1;
953 dprintk(1,"vbihack: %d\n",*fc);
954 }
955
956 /* copy stuff */
957 bytes = count;
958 if (bytes > q->read_buf->size - q->read_off)
959 bytes = q->read_buf->size - q->read_off;
960 if (copy_to_user(data + retval,
961 q->read_buf->dma.vmalloc + q->read_off,
962 bytes)) {
963 if (0 == retval)
964 retval = -EFAULT;
965 break;
966 }
967 count -= bytes;
968 retval += bytes;
969 q->read_off += bytes;
970 } else {
971 /* some error */
972 q->read_off = q->read_buf->size;
973 if (0 == retval)
974 retval = -EIO;
975 }
976
977 /* requeue buffer when done with copying */
978 if (q->read_off == q->read_buf->size) {
979 list_add_tail(&q->read_buf->stream,
980 &q->stream);
981 spin_lock_irqsave(q->irqlock,flags);
982 q->ops->buf_queue(q,q->read_buf);
983 spin_unlock_irqrestore(q->irqlock,flags);
984 q->read_buf = NULL;
985 }
986 if (retval < 0)
987 break;
988 }
989
990 done:
991 up(&q->lock);
992 return retval;
993 }
994
995 unsigned int videobuf_poll_stream(struct file *file,
996 struct videobuf_queue *q,
997 poll_table *wait)
998 {
999 struct videobuf_buffer *buf = NULL;
1000 unsigned int rc = 0;
1001
1002 down(&q->lock);
1003 if (q->streaming) {
1004 if (!list_empty(&q->stream))
1005 buf = list_entry(q->stream.next,
1006 struct videobuf_buffer, stream);
1007 } else {
1008 if (!q->reading)
1009 videobuf_read_start(q);
1010 if (!q->reading) {
1011 rc = POLLERR;
1012 } else if (NULL == q->read_buf) {
1013 q->read_buf = list_entry(q->stream.next,
1014 struct videobuf_buffer,
1015 stream);
1016 list_del(&q->read_buf->stream);
1017 q->read_off = 0;
1018 }
1019 buf = q->read_buf;
1020 }
1021 if (!buf)
1022 rc = POLLERR;
1023
1024 if (0 == rc) {
1025 poll_wait(file, &buf->done, wait);
1026 if (buf->state == STATE_DONE ||
1027 buf->state == STATE_ERROR)
1028 rc = POLLIN|POLLRDNORM;
1029 }
1030 up(&q->lock);
1031 return rc;
1032 }
1033
1034 /* --------------------------------------------------------------------- */
1035
1036 static void
1037 videobuf_vm_open(struct vm_area_struct *vma)
1038 {
1039 struct videobuf_mapping *map = vma->vm_private_data;
1040
1041 dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
1042 map->count,vma->vm_start,vma->vm_end);
1043 map->count++;
1044 }
1045
1046 static void
1047 videobuf_vm_close(struct vm_area_struct *vma)
1048 {
1049 struct videobuf_mapping *map = vma->vm_private_data;
1050 struct videobuf_queue *q = map->q;
1051 int i;
1052
1053 dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
1054 map->count,vma->vm_start,vma->vm_end);
1055
1056 map->count--;
1057 if (0 == map->count) {
1058 dprintk(1,"munmap %p q=%p\n",map,q);
1059 down(&q->lock);
1060 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1061 if (NULL == q->bufs[i])
1062 continue;
1063 if (q->bufs[i])
1064 ;
1065 if (q->bufs[i]->map != map)
1066 continue;
1067 q->bufs[i]->map = NULL;
1068 q->bufs[i]->baddr = 0;
1069 q->ops->buf_release(q,q->bufs[i]);
1070 }
1071 up(&q->lock);
1072 kfree(map);
1073 }
1074 return;
1075 }
1076
1077 /*
1078 * Get a anonymous page for the mapping. Make sure we can DMA to that
1079 * memory location with 32bit PCI devices (i.e. don't use highmem for
1080 * now ...). Bounce buffers don't work very well for the data rates
1081 * video capture has.
1082 */
1083 static struct page*
1084 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
1085 int *type)
1086 {
1087 struct page *page;
1088
1089 dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
1090 vaddr,vma->vm_start,vma->vm_end);
1091 if (vaddr > vma->vm_end)
1092 return NOPAGE_SIGBUS;
1093 page = alloc_page(GFP_USER);
1094 if (!page)
1095 return NOPAGE_OOM;
1096 clear_user_page(page_address(page), vaddr, page);
1097 if (type)
1098 *type = VM_FAULT_MINOR;
1099 return page;
1100 }
1101
1102 static struct vm_operations_struct videobuf_vm_ops =
1103 {
1104 .open = videobuf_vm_open,
1105 .close = videobuf_vm_close,
1106 .nopage = videobuf_vm_nopage,
1107 };
1108
1109 int videobuf_mmap_setup(struct videobuf_queue *q,
1110 unsigned int bcount, unsigned int bsize,
1111 enum v4l2_memory memory)
1112 {
1113 unsigned int i;
1114 int err;
1115
1116 err = videobuf_mmap_free(q);
1117 if (0 != err)
1118 return err;
1119
1120 for (i = 0; i < bcount; i++) {
1121 q->bufs[i] = videobuf_alloc(q->msize);
1122 q->bufs[i]->i = i;
1123 q->bufs[i]->input = UNSET;
1124 q->bufs[i]->memory = memory;
1125 q->bufs[i]->bsize = bsize;
1126 switch (memory) {
1127 case V4L2_MEMORY_MMAP:
1128 q->bufs[i]->boff = bsize * i;
1129 break;
1130 case V4L2_MEMORY_USERPTR:
1131 case V4L2_MEMORY_OVERLAY:
1132 /* nothing */
1133 break;
1134 }
1135 }
1136 dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
1137 bcount,bsize);
1138 return 0;
1139 }
1140
1141 int videobuf_mmap_free(struct videobuf_queue *q)
1142 {
1143 int i;
1144
1145 for (i = 0; i < VIDEO_MAX_FRAME; i++)
1146 if (q->bufs[i] && q->bufs[i]->map)
1147 return -EBUSY;
1148 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1149 if (NULL == q->bufs[i])
1150 continue;
1151 q->ops->buf_release(q,q->bufs[i]);
1152 kfree(q->bufs[i]);
1153 q->bufs[i] = NULL;
1154 }
1155 return 0;
1156 }
1157
1158 int videobuf_mmap_mapper(struct videobuf_queue *q,
1159 struct vm_area_struct *vma)
1160 {
1161 struct videobuf_mapping *map;
1162 unsigned int first,last,size,i;
1163 int retval;
1164
1165 down(&q->lock);
1166 retval = -EINVAL;
1167 if (!(vma->vm_flags & VM_WRITE)) {
1168 dprintk(1,"mmap app bug: PROT_WRITE please\n");
1169 goto done;
1170 }
1171 if (!(vma->vm_flags & VM_SHARED)) {
1172 dprintk(1,"mmap app bug: MAP_SHARED please\n");
1173 goto done;
1174 }
1175
1176 /* look for first buffer to map */
1177 for (first = 0; first < VIDEO_MAX_FRAME; first++) {
1178 if (NULL == q->bufs[first])
1179 continue;
1180 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
1181 continue;
1182 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
1183 break;
1184 }
1185 if (VIDEO_MAX_FRAME == first) {
1186 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
1187 (vma->vm_pgoff << PAGE_SHIFT));
1188 goto done;
1189 }
1190
1191 /* look for last buffer to map */
1192 for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
1193 if (NULL == q->bufs[last])
1194 continue;
1195 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
1196 continue;
1197 if (q->bufs[last]->map) {
1198 retval = -EBUSY;
1199 goto done;
1200 }
1201 size += q->bufs[last]->bsize;
1202 if (size == (vma->vm_end - vma->vm_start))
1203 break;
1204 }
1205 if (VIDEO_MAX_FRAME == last) {
1206 dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
1207 (vma->vm_end - vma->vm_start));
1208 goto done;
1209 }
1210
1211 /* create mapping + update buffer list */
1212 retval = -ENOMEM;
1213 map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
1214 if (NULL == map)
1215 goto done;
1216 for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
1217 q->bufs[i]->map = map;
1218 q->bufs[i]->baddr = vma->vm_start + size;
1219 }
1220 map->count = 1;
1221 map->start = vma->vm_start;
1222 map->end = vma->vm_end;
1223 map->q = q;
1224 vma->vm_ops = &videobuf_vm_ops;
1225 vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
1226 vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
1227 vma->vm_private_data = map;
1228 dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
1229 map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
1230 retval = 0;
1231
1232 done:
1233 up(&q->lock);
1234 return retval;
1235 }
1236
1237 /* --------------------------------------------------------------------- */
1238
1239 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
1240
1241 EXPORT_SYMBOL_GPL(videobuf_dma_init);
1242 EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
1243 EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
1244 EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
1245 EXPORT_SYMBOL_GPL(videobuf_dma_pci_map);
1246 EXPORT_SYMBOL_GPL(videobuf_dma_pci_sync);
1247 EXPORT_SYMBOL_GPL(videobuf_dma_pci_unmap);
1248 EXPORT_SYMBOL_GPL(videobuf_dma_free);
1249
1250 EXPORT_SYMBOL_GPL(videobuf_alloc);
1251 EXPORT_SYMBOL_GPL(videobuf_waiton);
1252 EXPORT_SYMBOL_GPL(videobuf_iolock);
1253
1254 EXPORT_SYMBOL_GPL(videobuf_queue_init);
1255 EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
1256 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
1257
1258 EXPORT_SYMBOL_GPL(videobuf_next_field);
1259 EXPORT_SYMBOL_GPL(videobuf_status);
1260 EXPORT_SYMBOL_GPL(videobuf_reqbufs);
1261 EXPORT_SYMBOL_GPL(videobuf_querybuf);
1262 EXPORT_SYMBOL_GPL(videobuf_qbuf);
1263 EXPORT_SYMBOL_GPL(videobuf_dqbuf);
1264 EXPORT_SYMBOL_GPL(videobuf_streamon);
1265 EXPORT_SYMBOL_GPL(videobuf_streamoff);
1266
1267 EXPORT_SYMBOL_GPL(videobuf_read_start);
1268 EXPORT_SYMBOL_GPL(videobuf_read_stop);
1269 EXPORT_SYMBOL_GPL(videobuf_read_stream);
1270 EXPORT_SYMBOL_GPL(videobuf_read_one);
1271 EXPORT_SYMBOL_GPL(videobuf_poll_stream);
1272
1273 EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
1274 EXPORT_SYMBOL_GPL(videobuf_mmap_free);
1275 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
1276
1277 /*
1278 * Local variables:
1279 * c-basic-offset: 8
1280 * End:
1281 */
1282
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