Merge master.kernel.org:/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog
[linux-2.6] / drivers / media / video / video-buf.c
1 /*
2  *
3  * generic helper functions for video4linux capture buffers, to handle
4  * memory management and PCI DMA.  Right now bttv + saa7134 use it.
5  *
6  * The functions expect the hardware being able to scatter gatter
7  * (i.e. the buffers are not linear in physical memory, but fragmented
8  * into PAGE_SIZE chunks).  They also assume the driver does not need
9  * to touch the video data (thus it is probably not useful for USB 1.1
10  * as data often must be uncompressed by the drivers).
11  *
12  * (c) 2001-2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  */
19
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/moduleparam.h>
23 #include <linux/vmalloc.h>
24 #include <linux/pagemap.h>
25 #include <linux/slab.h>
26 #include <linux/pci.h>
27 #include <linux/interrupt.h>
28 #include <asm/page.h>
29 #include <asm/pgtable.h>
30
31 #include <media/video-buf.h>
32
33 #define MAGIC_DMABUF 0x19721112
34 #define MAGIC_BUFFER 0x20040302
35 #define MAGIC_CHECK(is,should)  if (unlikely((is) != (should))) \
36         { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
37
38 static int debug = 0;
39 module_param(debug, int, 0644);
40
41 MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
42 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
43 MODULE_LICENSE("GPL");
44
45 #define dprintk(level, fmt, arg...)     if (debug >= level) \
46         printk(KERN_DEBUG "vbuf: " fmt , ## arg)
47
48 struct scatterlist*
49 videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
50 {
51         struct scatterlist *sglist;
52         struct page *pg;
53         int i;
54
55         sglist = kmalloc(sizeof(struct scatterlist)*nr_pages, GFP_KERNEL);
56         if (NULL == sglist)
57                 return NULL;
58         memset(sglist,0,sizeof(struct scatterlist)*nr_pages);
59         for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
60                 pg = vmalloc_to_page(virt);
61                 if (NULL == pg)
62                         goto err;
63                 if (PageHighMem(pg))
64                         BUG();
65                 sglist[i].page   = pg;
66                 sglist[i].length = PAGE_SIZE;
67         }
68         return sglist;
69
70  err:
71         kfree(sglist);
72         return NULL;
73 }
74
75 struct scatterlist*
76 videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
77 {
78         struct scatterlist *sglist;
79         int i = 0;
80
81         if (NULL == pages[0])
82                 return NULL;
83         sglist = kmalloc(sizeof(*sglist) * nr_pages, GFP_KERNEL);
84         if (NULL == sglist)
85                 return NULL;
86         memset(sglist, 0, sizeof(*sglist) * nr_pages);
87
88         if (NULL == pages[0])
89                 goto nopage;
90         if (PageHighMem(pages[0]))
91                 /* DMA to highmem pages might not work */
92                 goto highmem;
93         sglist[0].page   = pages[0];
94         sglist[0].offset = offset;
95         sglist[0].length = PAGE_SIZE - offset;
96         for (i = 1; i < nr_pages; i++) {
97                 if (NULL == pages[i])
98                         goto nopage;
99                 if (PageHighMem(pages[i]))
100                         goto highmem;
101                 sglist[i].page   = pages[i];
102                 sglist[i].length = PAGE_SIZE;
103         }
104         return sglist;
105
106  nopage:
107         dprintk(2,"sgl: oops - no page\n");
108         kfree(sglist);
109         return NULL;
110
111  highmem:
112         dprintk(2,"sgl: oops - highmem page\n");
113         kfree(sglist);
114         return NULL;
115 }
116
117 /* --------------------------------------------------------------------- */
118
119 void videobuf_dma_init(struct videobuf_dmabuf *dma)
120 {
121         memset(dma,0,sizeof(*dma));
122         dma->magic = MAGIC_DMABUF;
123 }
124
125 int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
126                            unsigned long data, unsigned long size)
127 {
128         unsigned long first,last;
129         int err, rw = 0;
130
131         dma->direction = direction;
132         switch (dma->direction) {
133         case PCI_DMA_FROMDEVICE: rw = READ;  break;
134         case PCI_DMA_TODEVICE:   rw = WRITE; break;
135         default:                 BUG();
136         }
137
138         first = (data          & PAGE_MASK) >> PAGE_SHIFT;
139         last  = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
140         dma->offset   = data & ~PAGE_MASK;
141         dma->nr_pages = last-first+1;
142         dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
143                              GFP_KERNEL);
144         if (NULL == dma->pages)
145                 return -ENOMEM;
146         dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
147                 data,size,dma->nr_pages);
148
149         down_read(&current->mm->mmap_sem);
150         err = get_user_pages(current,current->mm,
151                              data & PAGE_MASK, dma->nr_pages,
152                              rw == READ, 1, /* force */
153                              dma->pages, NULL);
154         up_read(&current->mm->mmap_sem);
155         if (err != dma->nr_pages) {
156                 dma->nr_pages = (err >= 0) ? err : 0;
157                 dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
158                 return err < 0 ? err : -EINVAL;
159         }
160         return 0;
161 }
162
163 int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
164                              int nr_pages)
165 {
166         dprintk(1,"init kernel [%d pages]\n",nr_pages);
167         dma->direction = direction;
168         dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
169         if (NULL == dma->vmalloc) {
170                 dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
171                 return -ENOMEM;
172         }
173         memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
174         dma->nr_pages = nr_pages;
175         return 0;
176 }
177
178 int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
179                               dma_addr_t addr, int nr_pages)
180 {
181         dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
182                 nr_pages,(unsigned long)addr);
183         dma->direction = direction;
184         if (0 == addr)
185                 return -EINVAL;
186
187         dma->bus_addr = addr;
188         dma->nr_pages = nr_pages;
189         return 0;
190 }
191
192 int videobuf_dma_pci_map(struct pci_dev *dev, struct videobuf_dmabuf *dma)
193 {
194         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
195         BUG_ON(0 == dma->nr_pages);
196
197         if (dma->pages) {
198                 dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
199                                                    dma->offset);
200         }
201         if (dma->vmalloc) {
202                 dma->sglist = videobuf_vmalloc_to_sg
203                         (dma->vmalloc,dma->nr_pages);
204         }
205         if (dma->bus_addr) {
206                 dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
207                 if (NULL != dma->sglist) {
208                         dma->sglen  = 1;
209                         sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
210                         dma->sglist[0].offset           = dma->bus_addr & ~PAGE_MASK;
211                         sg_dma_len(&dma->sglist[0])     = dma->nr_pages * PAGE_SIZE;
212                 }
213         }
214         if (NULL == dma->sglist) {
215                 dprintk(1,"scatterlist is NULL\n");
216                 return -ENOMEM;
217         }
218
219         if (!dma->bus_addr) {
220                 dma->sglen = pci_map_sg(dev,dma->sglist,dma->nr_pages,
221                                         dma->direction);
222                 if (0 == dma->sglen) {
223                         printk(KERN_WARNING
224                                "%s: pci_map_sg failed\n",__FUNCTION__);
225                         kfree(dma->sglist);
226                         dma->sglist = NULL;
227                         dma->sglen = 0;
228                         return -EIO;
229                 }
230         }
231         return 0;
232 }
233
234 int videobuf_dma_pci_sync(struct pci_dev *dev, struct videobuf_dmabuf *dma)
235 {
236         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
237         BUG_ON(!dma->sglen);
238
239         if (!dma->bus_addr)
240                 pci_dma_sync_sg_for_cpu(dev,dma->sglist,dma->nr_pages,dma->direction);
241         return 0;
242 }
243
244 int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma)
245 {
246         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
247         if (!dma->sglen)
248                 return 0;
249
250         if (!dma->bus_addr)
251                 pci_unmap_sg(dev,dma->sglist,dma->nr_pages,dma->direction);
252         kfree(dma->sglist);
253         dma->sglist = NULL;
254         dma->sglen = 0;
255         return 0;
256 }
257
258 int videobuf_dma_free(struct videobuf_dmabuf *dma)
259 {
260         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
261         BUG_ON(dma->sglen);
262
263         if (dma->pages) {
264                 int i;
265                 for (i=0; i < dma->nr_pages; i++)
266                         page_cache_release(dma->pages[i]);
267                 kfree(dma->pages);
268                 dma->pages = NULL;
269         }
270
271         vfree(dma->vmalloc);
272         dma->vmalloc = NULL;
273
274         if (dma->bus_addr) {
275                 dma->bus_addr = 0;
276         }
277         dma->direction = PCI_DMA_NONE;
278         return 0;
279 }
280
281 /* --------------------------------------------------------------------- */
282
283 void* videobuf_alloc(unsigned int size)
284 {
285         struct videobuf_buffer *vb;
286
287         vb = kmalloc(size,GFP_KERNEL);
288         if (NULL != vb) {
289                 memset(vb,0,size);
290                 videobuf_dma_init(&vb->dma);
291                 init_waitqueue_head(&vb->done);
292                 vb->magic     = MAGIC_BUFFER;
293         }
294         return vb;
295 }
296
297 int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
298 {
299         int retval = 0;
300         DECLARE_WAITQUEUE(wait, current);
301
302         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
303         add_wait_queue(&vb->done, &wait);
304         while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
305                 if (non_blocking) {
306                         retval = -EAGAIN;
307                         break;
308                 }
309                 set_current_state(intr  ? TASK_INTERRUPTIBLE
310                                         : TASK_UNINTERRUPTIBLE);
311                 if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
312                         schedule();
313                 set_current_state(TASK_RUNNING);
314                 if (intr && signal_pending(current)) {
315                         dprintk(1,"buffer waiton: -EINTR\n");
316                         retval = -EINTR;
317                         break;
318                 }
319         }
320         remove_wait_queue(&vb->done, &wait);
321         return retval;
322 }
323
324 int
325 videobuf_iolock(struct pci_dev *pci, struct videobuf_buffer *vb,
326                 struct v4l2_framebuffer *fbuf)
327 {
328         int err,pages;
329         dma_addr_t bus;
330
331         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
332         switch (vb->memory) {
333         case V4L2_MEMORY_MMAP:
334         case V4L2_MEMORY_USERPTR:
335                 if (0 == vb->baddr) {
336                         /* no userspace addr -- kernel bounce buffer */
337                         pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
338                         err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
339                                                        pages);
340                         if (0 != err)
341                                 return err;
342                 } else {
343                         /* dma directly to userspace */
344                         err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
345                                                      vb->baddr,vb->bsize);
346                         if (0 != err)
347                                 return err;
348                 }
349                 break;
350         case V4L2_MEMORY_OVERLAY:
351                 if (NULL == fbuf)
352                         return -EINVAL;
353                 /* FIXME: need sanity checks for vb->boff */
354                 bus   = (dma_addr_t)fbuf->base + vb->boff;
355                 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
356                 err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
357                                                 bus, pages);
358                 if (0 != err)
359                         return err;
360                 break;
361         default:
362                 BUG();
363         }
364         err = videobuf_dma_pci_map(pci,&vb->dma);
365         if (0 != err)
366                 return err;
367
368         return 0;
369 }
370
371 /* --------------------------------------------------------------------- */
372
373 void videobuf_queue_init(struct videobuf_queue* q,
374                          struct videobuf_queue_ops *ops,
375                          struct pci_dev *pci,
376                          spinlock_t *irqlock,
377                          enum v4l2_buf_type type,
378                          enum v4l2_field field,
379                          unsigned int msize,
380                          void *priv)
381 {
382         memset(q,0,sizeof(*q));
383         q->irqlock = irqlock;
384         q->pci     = pci;
385         q->type    = type;
386         q->field   = field;
387         q->msize   = msize;
388         q->ops     = ops;
389         q->priv_data = priv;
390
391         init_MUTEX(&q->lock);
392         INIT_LIST_HEAD(&q->stream);
393 }
394
395 int
396 videobuf_queue_is_busy(struct videobuf_queue *q)
397 {
398         int i;
399
400         if (q->streaming) {
401                 dprintk(1,"busy: streaming active\n");
402                 return 1;
403         }
404         if (q->reading) {
405                 dprintk(1,"busy: pending read #1\n");
406                 return 1;
407         }
408         if (q->read_buf) {
409                 dprintk(1,"busy: pending read #2\n");
410                 return 1;
411         }
412         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
413                 if (NULL == q->bufs[i])
414                         continue;
415                 if (q->bufs[i]->map) {
416                         dprintk(1,"busy: buffer #%d mapped\n",i);
417                         return 1;
418                 }
419                 if (q->bufs[i]->state == STATE_QUEUED) {
420                         dprintk(1,"busy: buffer #%d queued\n",i);
421                         return 1;
422                 }
423                 if (q->bufs[i]->state == STATE_ACTIVE) {
424                         dprintk(1,"busy: buffer #%d avtive\n",i);
425                         return 1;
426                 }
427         }
428         return 0;
429 }
430
431 void
432 videobuf_queue_cancel(struct videobuf_queue *q)
433 {
434         unsigned long flags;
435         int i;
436
437         /* remove queued buffers from list */
438         spin_lock_irqsave(q->irqlock,flags);
439         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
440                 if (NULL == q->bufs[i])
441                         continue;
442                 if (q->bufs[i]->state == STATE_QUEUED) {
443                         list_del(&q->bufs[i]->queue);
444                         q->bufs[i]->state = STATE_ERROR;
445                 }
446         }
447         spin_unlock_irqrestore(q->irqlock,flags);
448
449         /* free all buffers + clear queue */
450         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
451                 if (NULL == q->bufs[i])
452                         continue;
453                 q->ops->buf_release(q,q->bufs[i]);
454         }
455         INIT_LIST_HEAD(&q->stream);
456 }
457
458 /* --------------------------------------------------------------------- */
459
460 enum v4l2_field
461 videobuf_next_field(struct videobuf_queue *q)
462 {
463         enum v4l2_field field = q->field;
464
465         BUG_ON(V4L2_FIELD_ANY == field);
466
467         if (V4L2_FIELD_ALTERNATE == field) {
468                 if (V4L2_FIELD_TOP == q->last) {
469                         field   = V4L2_FIELD_BOTTOM;
470                         q->last = V4L2_FIELD_BOTTOM;
471                 } else {
472                         field   = V4L2_FIELD_TOP;
473                         q->last = V4L2_FIELD_TOP;
474                 }
475         }
476         return field;
477 }
478
479 void
480 videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
481                 enum v4l2_buf_type type)
482 {
483         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
484
485         b->index    = vb->i;
486         b->type     = type;
487
488         b->memory   = vb->memory;
489         switch (b->memory) {
490         case V4L2_MEMORY_MMAP:
491                 b->m.offset  = vb->boff;
492                 b->length    = vb->bsize;
493                 break;
494         case V4L2_MEMORY_USERPTR:
495                 b->m.userptr = vb->baddr;
496                 b->length    = vb->bsize;
497                 break;
498         case V4L2_MEMORY_OVERLAY:
499                 b->m.offset  = vb->boff;
500                 break;
501         }
502
503         b->flags    = 0;
504         if (vb->map)
505                 b->flags |= V4L2_BUF_FLAG_MAPPED;
506
507         switch (vb->state) {
508         case STATE_PREPARED:
509         case STATE_QUEUED:
510         case STATE_ACTIVE:
511                 b->flags |= V4L2_BUF_FLAG_QUEUED;
512                 break;
513         case STATE_DONE:
514         case STATE_ERROR:
515                 b->flags |= V4L2_BUF_FLAG_DONE;
516                 break;
517         case STATE_NEEDS_INIT:
518         case STATE_IDLE:
519                 /* nothing */
520                 break;
521         }
522
523         if (vb->input != UNSET) {
524                 b->flags |= V4L2_BUF_FLAG_INPUT;
525                 b->input  = vb->input;
526         }
527
528         b->field     = vb->field;
529         b->timestamp = vb->ts;
530         b->bytesused = vb->size;
531         b->sequence  = vb->field_count >> 1;
532 }
533
534 int
535 videobuf_reqbufs(struct videobuf_queue *q,
536                  struct v4l2_requestbuffers *req)
537 {
538         unsigned int size,count;
539         int retval;
540
541         if (req->type != q->type)
542                 return -EINVAL;
543         if (req->count < 1)
544                 return -EINVAL;
545         if (req->memory != V4L2_MEMORY_MMAP     &&
546             req->memory != V4L2_MEMORY_USERPTR  &&
547             req->memory != V4L2_MEMORY_OVERLAY)
548                 return -EINVAL;
549
550         if (q->streaming)
551                 return -EBUSY;
552         if (!list_empty(&q->stream))
553                 return -EBUSY;
554
555         down(&q->lock);
556         count = req->count;
557         if (count > VIDEO_MAX_FRAME)
558                 count = VIDEO_MAX_FRAME;
559         size = 0;
560         q->ops->buf_setup(q,&count,&size);
561         size = PAGE_ALIGN(size);
562         dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
563                 count, size, (count*size)>>PAGE_SHIFT);
564
565         retval = videobuf_mmap_setup(q,count,size,req->memory);
566         if (retval < 0)
567                 goto done;
568
569         req->count = count;
570
571  done:
572         up(&q->lock);
573         return retval;
574 }
575
576 int
577 videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
578 {
579         if (unlikely(b->type != q->type))
580                 return -EINVAL;
581         if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME))
582                 return -EINVAL;
583         if (unlikely(NULL == q->bufs[b->index]))
584                 return -EINVAL;
585         videobuf_status(b,q->bufs[b->index],q->type);
586         return 0;
587 }
588
589 int
590 videobuf_qbuf(struct videobuf_queue *q,
591               struct v4l2_buffer *b)
592 {
593         struct videobuf_buffer *buf;
594         enum v4l2_field field;
595         unsigned long flags;
596         int retval;
597
598         down(&q->lock);
599         retval = -EBUSY;
600         if (q->reading)
601                 goto done;
602         retval = -EINVAL;
603         if (b->type != q->type)
604                 goto done;
605         if (b->index < 0 || b->index >= VIDEO_MAX_FRAME)
606                 goto done;
607         buf = q->bufs[b->index];
608         if (NULL == buf)
609                 goto done;
610         MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
611         if (buf->memory != b->memory)
612                 goto done;
613         if (buf->state == STATE_QUEUED ||
614             buf->state == STATE_ACTIVE)
615                 goto done;
616
617         if (b->flags & V4L2_BUF_FLAG_INPUT) {
618                 if (b->input >= q->inputs)
619                         goto done;
620                 buf->input = b->input;
621         } else {
622                 buf->input = UNSET;
623         }
624
625         switch (b->memory) {
626         case V4L2_MEMORY_MMAP:
627                 if (0 == buf->baddr)
628                         goto done;
629                 break;
630         case V4L2_MEMORY_USERPTR:
631                 if (b->length < buf->bsize)
632                         goto done;
633                 if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
634                         q->ops->buf_release(q,buf);
635                 buf->baddr = b->m.userptr;
636                 break;
637         case V4L2_MEMORY_OVERLAY:
638                 buf->boff = b->m.offset;
639                 break;
640         default:
641                 goto done;
642         }
643
644         field = videobuf_next_field(q);
645         retval = q->ops->buf_prepare(q,buf,field);
646         if (0 != retval)
647                 goto done;
648
649         list_add_tail(&buf->stream,&q->stream);
650         if (q->streaming) {
651                 spin_lock_irqsave(q->irqlock,flags);
652                 q->ops->buf_queue(q,buf);
653                 spin_unlock_irqrestore(q->irqlock,flags);
654         }
655         retval = 0;
656
657  done:
658         up(&q->lock);
659         return retval;
660 }
661
662 int
663 videobuf_dqbuf(struct videobuf_queue *q,
664                struct v4l2_buffer *b, int nonblocking)
665 {
666         struct videobuf_buffer *buf;
667         int retval;
668
669         down(&q->lock);
670         retval = -EBUSY;
671         if (q->reading)
672                 goto done;
673         retval = -EINVAL;
674         if (b->type != q->type)
675                 goto done;
676         if (list_empty(&q->stream))
677                 goto done;
678         buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
679         retval = videobuf_waiton(buf, nonblocking, 1);
680         if (retval < 0)
681                 goto done;
682         switch (buf->state) {
683         case STATE_ERROR:
684                 retval = -EIO;
685                 /* fall through */
686         case STATE_DONE:
687                 videobuf_dma_pci_sync(q->pci,&buf->dma);
688                 buf->state = STATE_IDLE;
689                 break;
690         default:
691                 retval = -EINVAL;
692                 goto done;
693         }
694         list_del(&buf->stream);
695         memset(b,0,sizeof(*b));
696         videobuf_status(b,buf,q->type);
697
698  done:
699         up(&q->lock);
700         return retval;
701 }
702
703 int videobuf_streamon(struct videobuf_queue *q)
704 {
705         struct videobuf_buffer *buf;
706         struct list_head *list;
707         unsigned long flags;
708         int retval;
709
710         down(&q->lock);
711         retval = -EBUSY;
712         if (q->reading)
713                 goto done;
714         retval = 0;
715         if (q->streaming)
716                 goto done;
717         q->streaming = 1;
718         spin_lock_irqsave(q->irqlock,flags);
719         list_for_each(list,&q->stream) {
720                 buf = list_entry(list, struct videobuf_buffer, stream);
721                 if (buf->state == STATE_PREPARED)
722                         q->ops->buf_queue(q,buf);
723         }
724         spin_unlock_irqrestore(q->irqlock,flags);
725
726  done:
727         up(&q->lock);
728         return retval;
729 }
730
731 int videobuf_streamoff(struct videobuf_queue *q)
732 {
733         int retval = -EINVAL;
734
735         down(&q->lock);
736         if (!q->streaming)
737                 goto done;
738         videobuf_queue_cancel(q);
739         q->streaming = 0;
740         retval = 0;
741
742  done:
743         up(&q->lock);
744         return retval;
745 }
746
747 static ssize_t
748 videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
749                        size_t count, loff_t *ppos)
750 {
751         enum v4l2_field field;
752         unsigned long flags;
753         int retval;
754
755         /* setup stuff */
756         retval = -ENOMEM;
757         q->read_buf = videobuf_alloc(q->msize);
758         if (NULL == q->read_buf)
759                 goto done;
760
761         q->read_buf->memory = V4L2_MEMORY_USERPTR;
762         q->read_buf->baddr  = (unsigned long)data;
763         q->read_buf->bsize  = count;
764         field = videobuf_next_field(q);
765         retval = q->ops->buf_prepare(q,q->read_buf,field);
766         if (0 != retval)
767                 goto done;
768
769         /* start capture & wait */
770         spin_lock_irqsave(q->irqlock,flags);
771         q->ops->buf_queue(q,q->read_buf);
772         spin_unlock_irqrestore(q->irqlock,flags);
773         retval = videobuf_waiton(q->read_buf,0,0);
774         if (0 == retval) {
775                 videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
776                 if (STATE_ERROR == q->read_buf->state)
777                         retval = -EIO;
778                 else
779                         retval = q->read_buf->size;
780         }
781
782  done:
783         /* cleanup */
784         q->ops->buf_release(q,q->read_buf);
785         kfree(q->read_buf);
786         q->read_buf = NULL;
787         return retval;
788 }
789
790 ssize_t videobuf_read_one(struct videobuf_queue *q,
791                           char __user *data, size_t count, loff_t *ppos,
792                           int nonblocking)
793 {
794         enum v4l2_field field;
795         unsigned long flags;
796         unsigned size, nbufs, bytes;
797         int retval;
798
799         down(&q->lock);
800
801         nbufs = 1; size = 0;
802         q->ops->buf_setup(q,&nbufs,&size);
803         if (NULL == q->read_buf  &&
804             count >= size        &&
805             !nonblocking) {
806                 retval = videobuf_read_zerocopy(q,data,count,ppos);
807                 if (retval >= 0  ||  retval == -EIO)
808                         /* ok, all done */
809                         goto done;
810                 /* fallback to kernel bounce buffer on failures */
811         }
812
813         if (NULL == q->read_buf) {
814                 /* need to capture a new frame */
815                 retval = -ENOMEM;
816                 q->read_buf = videobuf_alloc(q->msize);
817                 if (NULL == q->read_buf)
818                         goto done;
819                 q->read_buf->memory = V4L2_MEMORY_USERPTR;
820                 field = videobuf_next_field(q);
821                 retval = q->ops->buf_prepare(q,q->read_buf,field);
822                 if (0 != retval)
823                         goto done;
824                 spin_lock_irqsave(q->irqlock,flags);
825                 q->ops->buf_queue(q,q->read_buf);
826                 spin_unlock_irqrestore(q->irqlock,flags);
827                 q->read_off = 0;
828         }
829
830         /* wait until capture is done */
831         retval = videobuf_waiton(q->read_buf, nonblocking, 1);
832         if (0 != retval)
833                 goto done;
834         videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
835
836         if (STATE_ERROR == q->read_buf->state) {
837                 /* catch I/O errors */
838                 q->ops->buf_release(q,q->read_buf);
839                 kfree(q->read_buf);
840                 q->read_buf = NULL;
841                 retval = -EIO;
842                 goto done;
843         }
844
845         /* copy to userspace */
846         bytes = count;
847         if (bytes > q->read_buf->size - q->read_off)
848                 bytes = q->read_buf->size - q->read_off;
849         retval = -EFAULT;
850         if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
851                 goto done;
852
853         retval = bytes;
854         q->read_off += bytes;
855         if (q->read_off == q->read_buf->size) {
856                 /* all data copied, cleanup */
857                 q->ops->buf_release(q,q->read_buf);
858                 kfree(q->read_buf);
859                 q->read_buf = NULL;
860         }
861
862  done:
863         up(&q->lock);
864         return retval;
865 }
866
867 int videobuf_read_start(struct videobuf_queue *q)
868 {
869         enum v4l2_field field;
870         unsigned long flags;
871         int count = 0, size = 0;
872         int err, i;
873
874         q->ops->buf_setup(q,&count,&size);
875         if (count < 2)
876                 count = 2;
877         if (count > VIDEO_MAX_FRAME)
878                 count = VIDEO_MAX_FRAME;
879         size = PAGE_ALIGN(size);
880
881         err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
882         if (err)
883                 return err;
884         for (i = 0; i < count; i++) {
885                 field = videobuf_next_field(q);
886                 err = q->ops->buf_prepare(q,q->bufs[i],field);
887                 if (err)
888                         return err;
889                 list_add_tail(&q->bufs[i]->stream, &q->stream);
890         }
891         spin_lock_irqsave(q->irqlock,flags);
892         for (i = 0; i < count; i++)
893                 q->ops->buf_queue(q,q->bufs[i]);
894         spin_unlock_irqrestore(q->irqlock,flags);
895         q->reading = 1;
896         return 0;
897 }
898
899 void videobuf_read_stop(struct videobuf_queue *q)
900 {
901         int i;
902
903         videobuf_queue_cancel(q);
904         videobuf_mmap_free(q);
905         INIT_LIST_HEAD(&q->stream);
906         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
907                 if (NULL == q->bufs[i])
908                         continue;
909                 kfree(q->bufs[i]);
910                 q->bufs[i] = NULL;
911         }
912         q->read_buf = NULL;
913         q->reading  = 0;
914 }
915
916 ssize_t videobuf_read_stream(struct videobuf_queue *q,
917                              char __user *data, size_t count, loff_t *ppos,
918                              int vbihack, int nonblocking)
919 {
920         unsigned int *fc, bytes;
921         int err, retval;
922         unsigned long flags;
923
924         dprintk(2,"%s\n",__FUNCTION__);
925         down(&q->lock);
926         retval = -EBUSY;
927         if (q->streaming)
928                 goto done;
929         if (!q->reading) {
930                 retval = videobuf_read_start(q);
931                 if (retval < 0)
932                         goto done;
933         }
934
935         retval = 0;
936         while (count > 0) {
937                 /* get / wait for data */
938                 if (NULL == q->read_buf) {
939                         q->read_buf = list_entry(q->stream.next,
940                                                  struct videobuf_buffer,
941                                                  stream);
942                         list_del(&q->read_buf->stream);
943                         q->read_off = 0;
944                 }
945                 err = videobuf_waiton(q->read_buf, nonblocking, 1);
946                 if (err < 0) {
947                         if (0 == retval)
948                                 retval = err;
949                         break;
950                 }
951
952                 if (q->read_buf->state == STATE_DONE) {
953                         if (vbihack) {
954                                 /* dirty, undocumented hack -- pass the frame counter
955                                  * within the last four bytes of each vbi data block.
956                                  * We need that one to maintain backward compatibility
957                                  * to all vbi decoding software out there ... */
958                                 fc  = (unsigned int*)q->read_buf->dma.vmalloc;
959                                 fc += (q->read_buf->size>>2) -1;
960                                 *fc = q->read_buf->field_count >> 1;
961                                 dprintk(1,"vbihack: %d\n",*fc);
962                         }
963
964                         /* copy stuff */
965                         bytes = count;
966                         if (bytes > q->read_buf->size - q->read_off)
967                                 bytes = q->read_buf->size - q->read_off;
968                         if (copy_to_user(data + retval,
969                                          q->read_buf->dma.vmalloc + q->read_off,
970                                          bytes)) {
971                                 if (0 == retval)
972                                         retval = -EFAULT;
973                                 break;
974                         }
975                         count       -= bytes;
976                         retval      += bytes;
977                         q->read_off += bytes;
978                 } else {
979                         /* some error */
980                         q->read_off = q->read_buf->size;
981                         if (0 == retval)
982                                 retval = -EIO;
983                 }
984
985                 /* requeue buffer when done with copying */
986                 if (q->read_off == q->read_buf->size) {
987                         list_add_tail(&q->read_buf->stream,
988                                       &q->stream);
989                         spin_lock_irqsave(q->irqlock,flags);
990                         q->ops->buf_queue(q,q->read_buf);
991                         spin_unlock_irqrestore(q->irqlock,flags);
992                         q->read_buf = NULL;
993                 }
994                 if (retval < 0)
995                         break;
996         }
997
998  done:
999         up(&q->lock);
1000         return retval;
1001 }
1002
1003 unsigned int videobuf_poll_stream(struct file *file,
1004                                   struct videobuf_queue *q,
1005                                   poll_table *wait)
1006 {
1007         struct videobuf_buffer *buf = NULL;
1008         unsigned int rc = 0;
1009
1010         down(&q->lock);
1011         if (q->streaming) {
1012                 if (!list_empty(&q->stream))
1013                         buf = list_entry(q->stream.next,
1014                                          struct videobuf_buffer, stream);
1015         } else {
1016                 if (!q->reading)
1017                         videobuf_read_start(q);
1018                 if (!q->reading) {
1019                         rc = POLLERR;
1020                 } else if (NULL == q->read_buf) {
1021                         q->read_buf = list_entry(q->stream.next,
1022                                                  struct videobuf_buffer,
1023                                                  stream);
1024                         list_del(&q->read_buf->stream);
1025                         q->read_off = 0;
1026                 }
1027                 buf = q->read_buf;
1028         }
1029         if (!buf)
1030                 rc = POLLERR;
1031
1032         if (0 == rc) {
1033                 poll_wait(file, &buf->done, wait);
1034                 if (buf->state == STATE_DONE ||
1035                     buf->state == STATE_ERROR)
1036                         rc = POLLIN|POLLRDNORM;
1037         }
1038         up(&q->lock);
1039         return rc;
1040 }
1041
1042 /* --------------------------------------------------------------------- */
1043
1044 static void
1045 videobuf_vm_open(struct vm_area_struct *vma)
1046 {
1047         struct videobuf_mapping *map = vma->vm_private_data;
1048
1049         dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
1050                 map->count,vma->vm_start,vma->vm_end);
1051         map->count++;
1052 }
1053
1054 static void
1055 videobuf_vm_close(struct vm_area_struct *vma)
1056 {
1057         struct videobuf_mapping *map = vma->vm_private_data;
1058         struct videobuf_queue *q = map->q;
1059         int i;
1060
1061         dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
1062                 map->count,vma->vm_start,vma->vm_end);
1063
1064         map->count--;
1065         if (0 == map->count) {
1066                 dprintk(1,"munmap %p q=%p\n",map,q);
1067                 down(&q->lock);
1068                 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1069                         if (NULL == q->bufs[i])
1070                                 continue;
1071                         if (q->bufs[i])
1072                                 ;
1073                         if (q->bufs[i]->map != map)
1074                                 continue;
1075                         q->bufs[i]->map   = NULL;
1076                         q->bufs[i]->baddr = 0;
1077                         q->ops->buf_release(q,q->bufs[i]);
1078                 }
1079                 up(&q->lock);
1080                 kfree(map);
1081         }
1082         return;
1083 }
1084
1085 /*
1086  * Get a anonymous page for the mapping.  Make sure we can DMA to that
1087  * memory location with 32bit PCI devices (i.e. don't use highmem for
1088  * now ...).  Bounce buffers don't work very well for the data rates
1089  * video capture has.
1090  */
1091 static struct page*
1092 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
1093                    int *type)
1094 {
1095         struct page *page;
1096
1097         dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
1098                 vaddr,vma->vm_start,vma->vm_end);
1099         if (vaddr > vma->vm_end)
1100                 return NOPAGE_SIGBUS;
1101         page = alloc_page(GFP_USER);
1102         if (!page)
1103                 return NOPAGE_OOM;
1104         clear_user_page(page_address(page), vaddr, page);
1105         if (type)
1106                 *type = VM_FAULT_MINOR;
1107         return page;
1108 }
1109
1110 static struct vm_operations_struct videobuf_vm_ops =
1111 {
1112         .open     = videobuf_vm_open,
1113         .close    = videobuf_vm_close,
1114         .nopage   = videobuf_vm_nopage,
1115 };
1116
1117 int videobuf_mmap_setup(struct videobuf_queue *q,
1118                         unsigned int bcount, unsigned int bsize,
1119                         enum v4l2_memory memory)
1120 {
1121         unsigned int i;
1122         int err;
1123
1124         err = videobuf_mmap_free(q);
1125         if (0 != err)
1126                 return err;
1127
1128         for (i = 0; i < bcount; i++) {
1129                 q->bufs[i] = videobuf_alloc(q->msize);
1130                 q->bufs[i]->i      = i;
1131                 q->bufs[i]->input  = UNSET;
1132                 q->bufs[i]->memory = memory;
1133                 q->bufs[i]->bsize  = bsize;
1134                 switch (memory) {
1135                 case V4L2_MEMORY_MMAP:
1136                         q->bufs[i]->boff  = bsize * i;
1137                         break;
1138                 case V4L2_MEMORY_USERPTR:
1139                 case V4L2_MEMORY_OVERLAY:
1140                         /* nothing */
1141                         break;
1142                 }
1143         }
1144         dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
1145                 bcount,bsize);
1146         return 0;
1147 }
1148
1149 int videobuf_mmap_free(struct videobuf_queue *q)
1150 {
1151         int i;
1152
1153         for (i = 0; i < VIDEO_MAX_FRAME; i++)
1154                 if (q->bufs[i] && q->bufs[i]->map)
1155                         return -EBUSY;
1156         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1157                 if (NULL == q->bufs[i])
1158                         continue;
1159                 q->ops->buf_release(q,q->bufs[i]);
1160                 kfree(q->bufs[i]);
1161                 q->bufs[i] = NULL;
1162         }
1163         return 0;
1164 }
1165
1166 int videobuf_mmap_mapper(struct videobuf_queue *q,
1167                          struct vm_area_struct *vma)
1168 {
1169         struct videobuf_mapping *map;
1170         unsigned int first,last,size,i;
1171         int retval;
1172
1173         down(&q->lock);
1174         retval = -EINVAL;
1175         if (!(vma->vm_flags & VM_WRITE)) {
1176                 dprintk(1,"mmap app bug: PROT_WRITE please\n");
1177                 goto done;
1178         }
1179         if (!(vma->vm_flags & VM_SHARED)) {
1180                 dprintk(1,"mmap app bug: MAP_SHARED please\n");
1181                 goto done;
1182         }
1183
1184         /* look for first buffer to map */
1185         for (first = 0; first < VIDEO_MAX_FRAME; first++) {
1186                 if (NULL == q->bufs[first])
1187                         continue;
1188                 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
1189                         continue;
1190                 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
1191                         break;
1192         }
1193         if (VIDEO_MAX_FRAME == first) {
1194                 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
1195                         (vma->vm_pgoff << PAGE_SHIFT));
1196                 goto done;
1197         }
1198
1199         /* look for last buffer to map */
1200         for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
1201                 if (NULL == q->bufs[last])
1202                         continue;
1203                 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
1204                         continue;
1205                 if (q->bufs[last]->map) {
1206                         retval = -EBUSY;
1207                         goto done;
1208                 }
1209                 size += q->bufs[last]->bsize;
1210                 if (size == (vma->vm_end - vma->vm_start))
1211                         break;
1212         }
1213         if (VIDEO_MAX_FRAME == last) {
1214                 dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
1215                         (vma->vm_end - vma->vm_start));
1216                 goto done;
1217         }
1218
1219         /* create mapping + update buffer list */
1220         retval = -ENOMEM;
1221         map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
1222         if (NULL == map)
1223                 goto done;
1224         for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
1225                 q->bufs[i]->map   = map;
1226                 q->bufs[i]->baddr = vma->vm_start + size;
1227         }
1228         map->count    = 1;
1229         map->start    = vma->vm_start;
1230         map->end      = vma->vm_end;
1231         map->q        = q;
1232         vma->vm_ops   = &videobuf_vm_ops;
1233         vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
1234         vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
1235         vma->vm_private_data = map;
1236         dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
1237                 map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
1238         retval = 0;
1239
1240  done:
1241         up(&q->lock);
1242         return retval;
1243 }
1244
1245 /* --------------------------------------------------------------------- */
1246
1247 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
1248
1249 EXPORT_SYMBOL_GPL(videobuf_dma_init);
1250 EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
1251 EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
1252 EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
1253 EXPORT_SYMBOL_GPL(videobuf_dma_pci_map);
1254 EXPORT_SYMBOL_GPL(videobuf_dma_pci_sync);
1255 EXPORT_SYMBOL_GPL(videobuf_dma_pci_unmap);
1256 EXPORT_SYMBOL_GPL(videobuf_dma_free);
1257
1258 EXPORT_SYMBOL_GPL(videobuf_alloc);
1259 EXPORT_SYMBOL_GPL(videobuf_waiton);
1260 EXPORT_SYMBOL_GPL(videobuf_iolock);
1261
1262 EXPORT_SYMBOL_GPL(videobuf_queue_init);
1263 EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
1264 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
1265
1266 EXPORT_SYMBOL_GPL(videobuf_next_field);
1267 EXPORT_SYMBOL_GPL(videobuf_status);
1268 EXPORT_SYMBOL_GPL(videobuf_reqbufs);
1269 EXPORT_SYMBOL_GPL(videobuf_querybuf);
1270 EXPORT_SYMBOL_GPL(videobuf_qbuf);
1271 EXPORT_SYMBOL_GPL(videobuf_dqbuf);
1272 EXPORT_SYMBOL_GPL(videobuf_streamon);
1273 EXPORT_SYMBOL_GPL(videobuf_streamoff);
1274
1275 EXPORT_SYMBOL_GPL(videobuf_read_start);
1276 EXPORT_SYMBOL_GPL(videobuf_read_stop);
1277 EXPORT_SYMBOL_GPL(videobuf_read_stream);
1278 EXPORT_SYMBOL_GPL(videobuf_read_one);
1279 EXPORT_SYMBOL_GPL(videobuf_poll_stream);
1280
1281 EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
1282 EXPORT_SYMBOL_GPL(videobuf_mmap_free);
1283 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
1284
1285 /*
1286  * Local variables:
1287  * c-basic-offset: 8
1288  * End:
1289  */