2 * $Id: video-buf.c,v 1.17 2004/12/10 12:33:40 kraxel Exp $
4 * generic helper functions for video4linux capture buffers, to handle
5 * memory management and PCI DMA. Right now bttv + saa7134 use it.
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).
13 * (c) 2001-2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
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.
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>
30 #include <asm/pgtable.h>
32 #include <media/video-buf.h>
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(); }
40 module_param(debug, int, 0644);
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");
46 #define dprintk(level, fmt, arg...) if (debug >= level) \
47 printk(KERN_DEBUG "vbuf: " fmt , ## arg)
50 videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
52 struct scatterlist *sglist;
56 sglist = kmalloc(sizeof(struct scatterlist)*nr_pages, GFP_KERNEL);
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);
67 sglist[i].length = PAGE_SIZE;
77 videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
79 struct scatterlist *sglist;
84 sglist = kmalloc(sizeof(*sglist) * nr_pages, GFP_KERNEL);
87 memset(sglist, 0, sizeof(*sglist) * nr_pages);
91 if (PageHighMem(pages[0]))
92 /* DMA to highmem pages might not work */
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++) {
100 if (PageHighMem(pages[i]))
102 sglist[i].page = pages[i];
103 sglist[i].length = PAGE_SIZE;
108 dprintk(2,"sgl: oops - no page\n");
113 dprintk(2,"sgl: oops - highmem page\n");
118 /* --------------------------------------------------------------------- */
120 void videobuf_dma_init(struct videobuf_dmabuf *dma)
122 memset(dma,0,sizeof(*dma));
123 dma->magic = MAGIC_DMABUF;
126 int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
127 unsigned long data, unsigned long size)
129 unsigned long first,last;
132 dma->direction = direction;
133 switch (dma->direction) {
134 case PCI_DMA_FROMDEVICE: rw = READ; break;
135 case PCI_DMA_TODEVICE: rw = WRITE; break;
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*),
145 if (NULL == dma->pages)
147 dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
148 data,size,dma->nr_pages);
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 */
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;
164 int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
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);
174 memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
175 dma->nr_pages = nr_pages;
179 int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
180 dma_addr_t addr, int nr_pages)
182 dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
183 nr_pages,(unsigned long)addr);
184 dma->direction = direction;
188 dma->bus_addr = addr;
189 dma->nr_pages = nr_pages;
193 int videobuf_dma_pci_map(struct pci_dev *dev, struct videobuf_dmabuf *dma)
195 MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
196 BUG_ON(0 == dma->nr_pages);
199 dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
203 dma->sglist = videobuf_vmalloc_to_sg
204 (dma->vmalloc,dma->nr_pages);
207 dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
208 if (NULL != dma->sglist) {
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;
215 if (NULL == dma->sglist) {
216 dprintk(1,"scatterlist is NULL\n");
221 dma->sglen = pci_map_sg(dev,dma->sglist,dma->nr_pages,
226 int videobuf_dma_pci_sync(struct pci_dev *dev, struct videobuf_dmabuf *dma)
228 MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
232 pci_dma_sync_sg_for_cpu(dev,dma->sglist,dma->nr_pages,dma->direction);
236 int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma)
238 MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
243 pci_unmap_sg(dev,dma->sglist,dma->nr_pages,dma->direction);
250 int videobuf_dma_free(struct videobuf_dmabuf *dma)
252 MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
257 for (i=0; i < dma->nr_pages; i++)
258 page_cache_release(dma->pages[i]);
269 dma->direction = PCI_DMA_NONE;
273 /* --------------------------------------------------------------------- */
275 void* videobuf_alloc(unsigned int size)
277 struct videobuf_buffer *vb;
279 vb = kmalloc(size,GFP_KERNEL);
282 videobuf_dma_init(&vb->dma);
283 init_waitqueue_head(&vb->done);
284 vb->magic = MAGIC_BUFFER;
289 int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
292 DECLARE_WAITQUEUE(wait, current);
294 MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
295 add_wait_queue(&vb->done, &wait);
296 while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
301 set_current_state(intr ? TASK_INTERRUPTIBLE
302 : TASK_UNINTERRUPTIBLE);
303 if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
305 set_current_state(TASK_RUNNING);
306 if (intr && signal_pending(current)) {
307 dprintk(1,"buffer waiton: -EINTR\n");
312 remove_wait_queue(&vb->done, &wait);
317 videobuf_iolock(struct pci_dev *pci, struct videobuf_buffer *vb,
318 struct v4l2_framebuffer *fbuf)
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,
335 /* dma directly to userspace */
336 err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
337 vb->baddr,vb->bsize);
342 case V4L2_MEMORY_OVERLAY:
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,
356 err = videobuf_dma_pci_map(pci,&vb->dma);
363 /* --------------------------------------------------------------------- */
365 void videobuf_queue_init(struct videobuf_queue* q,
366 struct videobuf_queue_ops *ops,
369 enum v4l2_buf_type type,
370 enum v4l2_field field,
374 memset(q,0,sizeof(*q));
375 q->irqlock = irqlock;
383 init_MUTEX(&q->lock);
384 INIT_LIST_HEAD(&q->stream);
388 videobuf_queue_is_busy(struct videobuf_queue *q)
393 dprintk(1,"busy: streaming active\n");
397 dprintk(1,"busy: pending read #1\n");
401 dprintk(1,"busy: pending read #2\n");
404 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
405 if (NULL == q->bufs[i])
407 if (q->bufs[i]->map) {
408 dprintk(1,"busy: buffer #%d mapped\n",i);
411 if (q->bufs[i]->state == STATE_QUEUED) {
412 dprintk(1,"busy: buffer #%d queued\n",i);
415 if (q->bufs[i]->state == STATE_ACTIVE) {
416 dprintk(1,"busy: buffer #%d avtive\n",i);
424 videobuf_queue_cancel(struct videobuf_queue *q)
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])
434 if (q->bufs[i]->state == STATE_QUEUED) {
435 list_del(&q->bufs[i]->queue);
436 q->bufs[i]->state = STATE_ERROR;
439 spin_unlock_irqrestore(q->irqlock,flags);
441 /* free all buffers + clear queue */
442 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
443 if (NULL == q->bufs[i])
445 q->ops->buf_release(q,q->bufs[i]);
447 INIT_LIST_HEAD(&q->stream);
450 /* --------------------------------------------------------------------- */
453 videobuf_next_field(struct videobuf_queue *q)
455 enum v4l2_field field = q->field;
457 BUG_ON(V4L2_FIELD_ANY == field);
459 if (V4L2_FIELD_ALTERNATE == field) {
460 if (V4L2_FIELD_TOP == q->last) {
461 field = V4L2_FIELD_BOTTOM;
462 q->last = V4L2_FIELD_BOTTOM;
464 field = V4L2_FIELD_TOP;
465 q->last = V4L2_FIELD_TOP;
472 videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
473 enum v4l2_buf_type type)
475 MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
480 b->memory = vb->memory;
482 case V4L2_MEMORY_MMAP:
483 b->m.offset = vb->boff;
484 b->length = vb->bsize;
486 case V4L2_MEMORY_USERPTR:
487 b->m.userptr = vb->baddr;
488 b->length = vb->bsize;
490 case V4L2_MEMORY_OVERLAY:
491 b->m.offset = vb->boff;
497 b->flags |= V4L2_BUF_FLAG_MAPPED;
503 b->flags |= V4L2_BUF_FLAG_QUEUED;
507 b->flags |= V4L2_BUF_FLAG_DONE;
509 case STATE_NEEDS_INIT:
515 if (vb->input != UNSET) {
516 b->flags |= V4L2_BUF_FLAG_INPUT;
517 b->input = vb->input;
520 b->field = vb->field;
521 b->timestamp = vb->ts;
522 b->bytesused = vb->size;
523 b->sequence = vb->field_count >> 1;
527 videobuf_reqbufs(struct videobuf_queue *q,
528 struct v4l2_requestbuffers *req)
530 unsigned int size,count;
533 if (req->type != q->type)
537 if (req->memory != V4L2_MEMORY_MMAP &&
538 req->memory != V4L2_MEMORY_USERPTR &&
539 req->memory != V4L2_MEMORY_OVERLAY)
544 if (!list_empty(&q->stream))
549 if (count > VIDEO_MAX_FRAME)
550 count = VIDEO_MAX_FRAME;
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);
557 retval = videobuf_mmap_setup(q,count,size,req->memory);
569 videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
571 if (unlikely(b->type != q->type))
573 if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME))
575 if (unlikely(NULL == q->bufs[b->index]))
577 videobuf_status(b,q->bufs[b->index],q->type);
582 videobuf_qbuf(struct videobuf_queue *q,
583 struct v4l2_buffer *b)
585 struct videobuf_buffer *buf;
586 enum v4l2_field field;
595 if (b->type != q->type)
597 if (b->index < 0 || b->index >= VIDEO_MAX_FRAME)
599 buf = q->bufs[b->index];
602 MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
603 if (buf->memory != b->memory)
605 if (buf->state == STATE_QUEUED ||
606 buf->state == STATE_ACTIVE)
609 if (b->flags & V4L2_BUF_FLAG_INPUT) {
610 if (b->input >= q->inputs)
612 buf->input = b->input;
618 case V4L2_MEMORY_MMAP:
622 case V4L2_MEMORY_USERPTR:
623 if (b->length < buf->bsize)
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;
629 case V4L2_MEMORY_OVERLAY:
630 buf->boff = b->m.offset;
636 field = videobuf_next_field(q);
637 retval = q->ops->buf_prepare(q,buf,field);
641 list_add_tail(&buf->stream,&q->stream);
643 spin_lock_irqsave(q->irqlock,flags);
644 q->ops->buf_queue(q,buf);
645 spin_unlock_irqrestore(q->irqlock,flags);
655 videobuf_dqbuf(struct videobuf_queue *q,
656 struct v4l2_buffer *b, int nonblocking)
658 struct videobuf_buffer *buf;
666 if (b->type != q->type)
668 if (list_empty(&q->stream))
670 buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
671 retval = videobuf_waiton(buf, nonblocking, 1);
674 switch (buf->state) {
679 videobuf_dma_pci_sync(q->pci,&buf->dma);
680 buf->state = STATE_IDLE;
686 list_del(&buf->stream);
687 memset(b,0,sizeof(*b));
688 videobuf_status(b,buf,q->type);
695 int videobuf_streamon(struct videobuf_queue *q)
697 struct videobuf_buffer *buf;
698 struct list_head *list;
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);
716 spin_unlock_irqrestore(q->irqlock,flags);
723 int videobuf_streamoff(struct videobuf_queue *q)
725 int retval = -EINVAL;
730 videobuf_queue_cancel(q);
740 videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
741 size_t count, loff_t *ppos)
743 enum v4l2_field field;
749 q->read_buf = videobuf_alloc(q->msize);
750 if (NULL == q->read_buf)
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);
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);
767 videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
768 if (STATE_ERROR == q->read_buf->state)
771 retval = q->read_buf->size;
776 q->ops->buf_release(q,q->read_buf);
782 ssize_t videobuf_read_one(struct videobuf_queue *q,
783 char __user *data, size_t count, loff_t *ppos,
786 enum v4l2_field field;
788 unsigned size, nbufs, bytes;
794 q->ops->buf_setup(q,&nbufs,&size);
795 if (NULL == q->read_buf &&
798 retval = videobuf_read_zerocopy(q,data,count,ppos);
799 if (retval >= 0 || retval == -EIO)
802 /* fallback to kernel bounce buffer on failures */
805 if (NULL == q->read_buf) {
806 /* need to capture a new frame */
808 q->read_buf = videobuf_alloc(q->msize);
809 if (NULL == q->read_buf)
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);
816 spin_lock_irqsave(q->irqlock,flags);
817 q->ops->buf_queue(q,q->read_buf);
818 spin_unlock_irqrestore(q->irqlock,flags);
822 /* wait until capture is done */
823 retval = videobuf_waiton(q->read_buf, nonblocking, 1);
826 videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
828 if (STATE_ERROR == q->read_buf->state) {
829 /* catch I/O errors */
830 q->ops->buf_release(q,q->read_buf);
837 /* copy to userspace */
839 if (bytes > q->read_buf->size - q->read_off)
840 bytes = q->read_buf->size - q->read_off;
842 if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, 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);
859 int videobuf_read_start(struct videobuf_queue *q)
861 enum v4l2_field field;
863 int count = 0, size = 0;
866 q->ops->buf_setup(q,&count,&size);
869 if (count > VIDEO_MAX_FRAME)
870 count = VIDEO_MAX_FRAME;
871 size = PAGE_ALIGN(size);
873 err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
876 for (i = 0; i < count; i++) {
877 field = videobuf_next_field(q);
878 err = q->ops->buf_prepare(q,q->bufs[i],field);
881 list_add_tail(&q->bufs[i]->stream, &q->stream);
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);
891 void videobuf_read_stop(struct videobuf_queue *q)
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])
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)
912 unsigned int *fc, bytes;
916 dprintk(2,"%s\n",__FUNCTION__);
922 retval = videobuf_read_start(q);
929 /* get / wait for data */
930 if (NULL == q->read_buf) {
931 q->read_buf = list_entry(q->stream.next,
932 struct videobuf_buffer,
934 list_del(&q->read_buf->stream);
937 err = videobuf_waiton(q->read_buf, nonblocking, 1);
944 if (q->read_buf->state == STATE_DONE) {
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);
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,
969 q->read_off += bytes;
972 q->read_off = q->read_buf->size;
977 /* requeue buffer when done with copying */
978 if (q->read_off == q->read_buf->size) {
979 list_add_tail(&q->read_buf->stream,
981 spin_lock_irqsave(q->irqlock,flags);
982 q->ops->buf_queue(q,q->read_buf);
983 spin_unlock_irqrestore(q->irqlock,flags);
995 unsigned int videobuf_poll_stream(struct file *file,
996 struct videobuf_queue *q,
999 struct videobuf_buffer *buf = NULL;
1000 unsigned int rc = 0;
1004 if (!list_empty(&q->stream))
1005 buf = list_entry(q->stream.next,
1006 struct videobuf_buffer, stream);
1009 videobuf_read_start(q);
1012 } else if (NULL == q->read_buf) {
1013 q->read_buf = list_entry(q->stream.next,
1014 struct videobuf_buffer,
1016 list_del(&q->read_buf->stream);
1025 poll_wait(file, &buf->done, wait);
1026 if (buf->state == STATE_DONE ||
1027 buf->state == STATE_ERROR)
1028 rc = POLLIN|POLLRDNORM;
1034 /* --------------------------------------------------------------------- */
1037 videobuf_vm_open(struct vm_area_struct *vma)
1039 struct videobuf_mapping *map = vma->vm_private_data;
1041 dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
1042 map->count,vma->vm_start,vma->vm_end);
1047 videobuf_vm_close(struct vm_area_struct *vma)
1049 struct videobuf_mapping *map = vma->vm_private_data;
1050 struct videobuf_queue *q = map->q;
1053 dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
1054 map->count,vma->vm_start,vma->vm_end);
1057 if (0 == map->count) {
1058 dprintk(1,"munmap %p q=%p\n",map,q);
1060 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1061 if (NULL == q->bufs[i])
1065 if (q->bufs[i]->map != map)
1067 q->bufs[i]->map = NULL;
1068 q->bufs[i]->baddr = 0;
1069 q->ops->buf_release(q,q->bufs[i]);
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.
1084 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
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);
1096 clear_user_page(page_address(page), vaddr, page);
1098 *type = VM_FAULT_MINOR;
1102 static struct vm_operations_struct videobuf_vm_ops =
1104 .open = videobuf_vm_open,
1105 .close = videobuf_vm_close,
1106 .nopage = videobuf_vm_nopage,
1109 int videobuf_mmap_setup(struct videobuf_queue *q,
1110 unsigned int bcount, unsigned int bsize,
1111 enum v4l2_memory memory)
1116 err = videobuf_mmap_free(q);
1120 for (i = 0; i < bcount; i++) {
1121 q->bufs[i] = videobuf_alloc(q->msize);
1123 q->bufs[i]->input = UNSET;
1124 q->bufs[i]->memory = memory;
1125 q->bufs[i]->bsize = bsize;
1127 case V4L2_MEMORY_MMAP:
1128 q->bufs[i]->boff = bsize * i;
1130 case V4L2_MEMORY_USERPTR:
1131 case V4L2_MEMORY_OVERLAY:
1136 dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
1141 int videobuf_mmap_free(struct videobuf_queue *q)
1145 for (i = 0; i < VIDEO_MAX_FRAME; i++)
1146 if (q->bufs[i] && q->bufs[i]->map)
1148 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1149 if (NULL == q->bufs[i])
1151 q->ops->buf_release(q,q->bufs[i]);
1158 int videobuf_mmap_mapper(struct videobuf_queue *q,
1159 struct vm_area_struct *vma)
1161 struct videobuf_mapping *map;
1162 unsigned int first,last,size,i;
1167 if (!(vma->vm_flags & VM_WRITE)) {
1168 dprintk(1,"mmap app bug: PROT_WRITE please\n");
1171 if (!(vma->vm_flags & VM_SHARED)) {
1172 dprintk(1,"mmap app bug: MAP_SHARED please\n");
1176 /* look for first buffer to map */
1177 for (first = 0; first < VIDEO_MAX_FRAME; first++) {
1178 if (NULL == q->bufs[first])
1180 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
1182 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
1185 if (VIDEO_MAX_FRAME == first) {
1186 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
1187 (vma->vm_pgoff << PAGE_SHIFT));
1191 /* look for last buffer to map */
1192 for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
1193 if (NULL == q->bufs[last])
1195 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
1197 if (q->bufs[last]->map) {
1201 size += q->bufs[last]->bsize;
1202 if (size == (vma->vm_end - vma->vm_start))
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));
1211 /* create mapping + update buffer list */
1213 map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
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;
1221 map->start = vma->vm_start;
1222 map->end = vma->vm_end;
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);
1237 /* --------------------------------------------------------------------- */
1239 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
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);
1250 EXPORT_SYMBOL_GPL(videobuf_alloc);
1251 EXPORT_SYMBOL_GPL(videobuf_waiton);
1252 EXPORT_SYMBOL_GPL(videobuf_iolock);
1254 EXPORT_SYMBOL_GPL(videobuf_queue_init);
1255 EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
1256 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
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);
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);
1273 EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
1274 EXPORT_SYMBOL_GPL(videobuf_mmap_free);
1275 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);