Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1290 insertions, 0 deletions

diff --git a/drivers/media/video/video-buf.c b/drivers/media/video/video-buf.c
new file mode 100644
index 000000000000..5afdc7852610
--- /dev/null
+++ b/drivers/media/video/video-buf.c
@@ -0,0 +1,1290 @@
+/*
+ * $Id: video-buf.c,v 1.18 2005/02/24 13:32:30 kraxel Exp $
+ *
+ * generic helper functions for video4linux capture buffers, to handle
+ * memory management and PCI DMA.  Right now bttv + saa7134 use it.
+ *
+ * The functions expect the hardware being able to scatter gatter
+ * (i.e. the buffers are not linear in physical memory, but fragmented
+ * into PAGE_SIZE chunks).  They also assume the driver does not need
+ * to touch the video data (thus it is probably not useful for USB 1.1
+ * as data often must be uncompressed by the drivers).
+ *
+ * (c) 2001-2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+#include <media/video-buf.h>
+
+#define MAGIC_DMABUF 0x19721112
+#define MAGIC_BUFFER 0x20040302
+#define MAGIC_CHECK(is,should)	if (unlikely((is) != (should))) \
+	{ printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
+
+static int debug = 0;
+module_param(debug, int, 0644);
+
+MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
+MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
+MODULE_LICENSE("GPL");
+
+#define dprintk(level, fmt, arg...)	if (debug >= level) \
+	printk(KERN_DEBUG "vbuf: " fmt , ## arg)
+
+struct scatterlist*
+videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
+{
+	struct scatterlist *sglist;
+	struct page *pg;
+	int i;
+
+	sglist = kmalloc(sizeof(struct scatterlist)*nr_pages, GFP_KERNEL);
+	if (NULL == sglist)
+		return NULL;
+	memset(sglist,0,sizeof(struct scatterlist)*nr_pages);
+	for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
+		pg = vmalloc_to_page(virt);
+		if (NULL == pg)
+			goto err;
+		if (PageHighMem(pg))
+			BUG();
+		sglist[i].page   = pg;
+		sglist[i].length = PAGE_SIZE;
+	}
+	return sglist;
+
+ err:
+	kfree(sglist);
+	return NULL;
+}
+
+struct scatterlist*
+videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
+{
+	struct scatterlist *sglist;
+	int i = 0;
+
+	if (NULL == pages[0])
+		return NULL;
+	sglist = kmalloc(sizeof(*sglist) * nr_pages, GFP_KERNEL);
+	if (NULL == sglist)
+		return NULL;
+	memset(sglist, 0, sizeof(*sglist) * nr_pages);
+
+	if (NULL == pages[0])
+		goto nopage;
+	if (PageHighMem(pages[0]))
+		/* DMA to highmem pages might not work */
+		goto highmem;
+	sglist[0].page   = pages[0];
+	sglist[0].offset = offset;
+	sglist[0].length = PAGE_SIZE - offset;
+	for (i = 1; i < nr_pages; i++) {
+		if (NULL == pages[i])
+			goto nopage;
+		if (PageHighMem(pages[i]))
+			goto highmem;
+		sglist[i].page   = pages[i];
+		sglist[i].length = PAGE_SIZE;
+	}
+	return sglist;
+
+ nopage:
+	dprintk(2,"sgl: oops - no page\n");
+	kfree(sglist);
+	return NULL;
+
+ highmem:
+	dprintk(2,"sgl: oops - highmem page\n");
+	kfree(sglist);
+	return NULL;
+}
+
+/* --------------------------------------------------------------------- */
+
+void videobuf_dma_init(struct videobuf_dmabuf *dma)
+{
+	memset(dma,0,sizeof(*dma));
+	dma->magic = MAGIC_DMABUF;
+}
+
+int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
+			   unsigned long data, unsigned long size)
+{
+	unsigned long first,last;
+	int err, rw = 0;
+
+	dma->direction = direction;
+	switch (dma->direction) {
+	case PCI_DMA_FROMDEVICE: rw = READ;  break;
+	case PCI_DMA_TODEVICE:   rw = WRITE; break;
+	default:                 BUG();
+	}
+
+	first = (data          & PAGE_MASK) >> PAGE_SHIFT;
+	last  = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
+	dma->offset   = data & ~PAGE_MASK;
+	dma->nr_pages = last-first+1;
+	dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
+			     GFP_KERNEL);
+	if (NULL == dma->pages)
+		return -ENOMEM;
+	dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
+		data,size,dma->nr_pages);
+
+	down_read(&current->mm->mmap_sem);
+        err = get_user_pages(current,current->mm,
+			     data & PAGE_MASK, dma->nr_pages,
+			     rw == READ, 1, /* force */
+			     dma->pages, NULL);
+	up_read(&current->mm->mmap_sem);
+	if (err != dma->nr_pages) {
+		dma->nr_pages = (err >= 0) ? err : 0;
+		dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
+		return err < 0 ? err : -EINVAL;
+	}
+	return 0;
+}
+
+int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
+			     int nr_pages)
+{
+	dprintk(1,"init kernel [%d pages]\n",nr_pages);
+	dma->direction = direction;
+	dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
+	if (NULL == dma->vmalloc) {
+		dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
+		return -ENOMEM;
+	}
+	memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
+	dma->nr_pages = nr_pages;
+	return 0;
+}
+
+int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
+			      dma_addr_t addr, int nr_pages)
+{
+	dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
+		nr_pages,(unsigned long)addr);
+	dma->direction = direction;
+	if (0 == addr)
+		return -EINVAL;
+
+	dma->bus_addr = addr;
+	dma->nr_pages = nr_pages;
+	return 0;
+}
+
+int videobuf_dma_pci_map(struct pci_dev *dev, struct videobuf_dmabuf *dma)
+{
+	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
+	BUG_ON(0 == dma->nr_pages);
+
+	if (dma->pages) {
+		dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
+						   dma->offset);
+	}
+	if (dma->vmalloc) {
+		dma->sglist = videobuf_vmalloc_to_sg
+			(dma->vmalloc,dma->nr_pages);
+	}
+	if (dma->bus_addr) {
+		dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
+		if (NULL != dma->sglist) {
+			dma->sglen  = 1;
+			sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
+			dma->sglist[0].offset           = dma->bus_addr & ~PAGE_MASK;
+			sg_dma_len(&dma->sglist[0])     = dma->nr_pages * PAGE_SIZE;
+		}
+	}
+	if (NULL == dma->sglist) {
+		dprintk(1,"scatterlist is NULL\n");
+		return -ENOMEM;
+	}
+
+	if (!dma->bus_addr) {
+		dma->sglen = pci_map_sg(dev,dma->sglist,dma->nr_pages,
+					dma->direction);
+		if (0 == dma->sglen) {
+			printk(KERN_WARNING
+			       "%s: pci_map_sg failed\n",__FUNCTION__);
+			kfree(dma->sglist);
+			dma->sglist = NULL;
+			dma->sglen = 0;
+			return -EIO;
+		}
+	}
+	return 0;
+}
+
+int videobuf_dma_pci_sync(struct pci_dev *dev, struct videobuf_dmabuf *dma)
+{
+	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
+	BUG_ON(!dma->sglen);
+
+	if (!dma->bus_addr)
+		pci_dma_sync_sg_for_cpu(dev,dma->sglist,dma->nr_pages,dma->direction);
+	return 0;
+}
+
+int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma)
+{
+	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
+	if (!dma->sglen)
+		return 0;
+
+	if (!dma->bus_addr)
+		pci_unmap_sg(dev,dma->sglist,dma->nr_pages,dma->direction);
+	kfree(dma->sglist);
+	dma->sglist = NULL;
+	dma->sglen = 0;
+	return 0;
+}
+
+int videobuf_dma_free(struct videobuf_dmabuf *dma)
+{
+	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
+	BUG_ON(dma->sglen);
+
+	if (dma->pages) {
+		int i;
+		for (i=0; i < dma->nr_pages; i++)
+			page_cache_release(dma->pages[i]);
+		kfree(dma->pages);
+		dma->pages = NULL;
+	}
+	if (dma->vmalloc) {
+		vfree(dma->vmalloc);
+		dma->vmalloc = NULL;
+	}
+	if (dma->bus_addr) {
+		dma->bus_addr = 0;
+	}
+	dma->direction = PCI_DMA_NONE;
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+void* videobuf_alloc(unsigned int size)
+{
+	struct videobuf_buffer *vb;
+
+	vb = kmalloc(size,GFP_KERNEL);
+	if (NULL != vb) {
+		memset(vb,0,size);
+		videobuf_dma_init(&vb->dma);
+		init_waitqueue_head(&vb->done);
+		vb->magic     = MAGIC_BUFFER;
+	}
+	return vb;
+}
+
+int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
+{
+	int retval = 0;
+	DECLARE_WAITQUEUE(wait, current);
+
+	MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
+	add_wait_queue(&vb->done, &wait);
+	while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
+		if (non_blocking) {
+			retval = -EAGAIN;
+			break;
+		}
+		set_current_state(intr  ? TASK_INTERRUPTIBLE
+					: TASK_UNINTERRUPTIBLE);
+		if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
+			schedule();
+		set_current_state(TASK_RUNNING);
+		if (intr && signal_pending(current)) {
+			dprintk(1,"buffer waiton: -EINTR\n");
+			retval = -EINTR;
+			break;
+		}
+	}
+	remove_wait_queue(&vb->done, &wait);
+	return retval;
+}
+
+int
+videobuf_iolock(struct pci_dev *pci, struct videobuf_buffer *vb,
+		struct v4l2_framebuffer *fbuf)
+{
+	int err,pages;
+	dma_addr_t bus;
+
+	MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
+	switch (vb->memory) {
+	case V4L2_MEMORY_MMAP:
+	case V4L2_MEMORY_USERPTR:
+		if (0 == vb->baddr) {
+			/* no userspace addr -- kernel bounce buffer */
+			pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
+			err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
+						       pages);
+			if (0 != err)
+				return err;
+		} else {
+			/* dma directly to userspace */
+			err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
+						     vb->baddr,vb->bsize);
+			if (0 != err)
+				return err;
+		}
+		break;
+	case V4L2_MEMORY_OVERLAY:
+		if (NULL == fbuf)
+			return -EINVAL;
+		/* FIXME: need sanity checks for vb->boff */
+		bus   = (dma_addr_t)fbuf->base + vb->boff;
+		pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
+		err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
+						bus, pages);
+		if (0 != err)
+			return err;
+		break;
+	default:
+		BUG();
+	}
+	err = videobuf_dma_pci_map(pci,&vb->dma);
+	if (0 != err)
+		return err;
+
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+void videobuf_queue_init(struct videobuf_queue* q,
+			 struct videobuf_queue_ops *ops,
+			 struct pci_dev *pci,
+			 spinlock_t *irqlock,
+			 enum v4l2_buf_type type,
+			 enum v4l2_field field,
+			 unsigned int msize,
+			 void *priv)
+{
+	memset(q,0,sizeof(*q));
+	q->irqlock = irqlock;
+	q->pci     = pci;
+	q->type    = type;
+	q->field   = field;
+	q->msize   = msize;
+	q->ops     = ops;
+	q->priv_data = priv;
+
+	init_MUTEX(&q->lock);
+	INIT_LIST_HEAD(&q->stream);
+}
+
+int
+videobuf_queue_is_busy(struct videobuf_queue *q)
+{
+	int i;
+
+	if (q->streaming) {
+		dprintk(1,"busy: streaming active\n");
+		return 1;
+	}
+	if (q->reading) {
+		dprintk(1,"busy: pending read #1\n");
+		return 1;
+	}
+	if (q->read_buf) {
+		dprintk(1,"busy: pending read #2\n");
+		return 1;
+	}
+	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+		if (NULL == q->bufs[i])
+			continue;
+		if (q->bufs[i]->map) {
+			dprintk(1,"busy: buffer #%d mapped\n",i);
+			return 1;
+		}
+		if (q->bufs[i]->state == STATE_QUEUED) {
+			dprintk(1,"busy: buffer #%d queued\n",i);
+			return 1;
+		}
+		if (q->bufs[i]->state == STATE_ACTIVE) {
+			dprintk(1,"busy: buffer #%d avtive\n",i);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+void
+videobuf_queue_cancel(struct videobuf_queue *q)
+{
+	unsigned long flags;
+	int i;
+
+	/* remove queued buffers from list */
+	spin_lock_irqsave(q->irqlock,flags);
+	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+		if (NULL == q->bufs[i])
+			continue;
+		if (q->bufs[i]->state == STATE_QUEUED) {
+			list_del(&q->bufs[i]->queue);
+			q->bufs[i]->state = STATE_ERROR;
+		}
+	}
+	spin_unlock_irqrestore(q->irqlock,flags);
+
+	/* free all buffers + clear queue */
+	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+		if (NULL == q->bufs[i])
+			continue;
+		q->ops->buf_release(q,q->bufs[i]);
+	}
+	INIT_LIST_HEAD(&q->stream);
+}
+
+/* --------------------------------------------------------------------- */
+
+enum v4l2_field
+videobuf_next_field(struct videobuf_queue *q)
+{
+	enum v4l2_field field = q->field;
+
+	BUG_ON(V4L2_FIELD_ANY == field);
+
+	if (V4L2_FIELD_ALTERNATE == field) {
+		if (V4L2_FIELD_TOP == q->last) {
+			field   = V4L2_FIELD_BOTTOM;
+			q->last = V4L2_FIELD_BOTTOM;
+		} else {
+			field   = V4L2_FIELD_TOP;
+			q->last = V4L2_FIELD_TOP;
+		}
+	}
+	return field;
+}
+
+void
+videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
+		enum v4l2_buf_type type)
+{
+	MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
+
+	b->index    = vb->i;
+	b->type     = type;
+
+	b->memory   = vb->memory;
+	switch (b->memory) {
+	case V4L2_MEMORY_MMAP:
+		b->m.offset  = vb->boff;
+		b->length    = vb->bsize;
+		break;
+	case V4L2_MEMORY_USERPTR:
+		b->m.userptr = vb->baddr;
+		b->length    = vb->bsize;
+		break;
+	case V4L2_MEMORY_OVERLAY:
+		b->m.offset  = vb->boff;
+		break;
+	}
+
+	b->flags    = 0;
+	if (vb->map)
+		b->flags |= V4L2_BUF_FLAG_MAPPED;
+
+	switch (vb->state) {
+	case STATE_PREPARED:
+	case STATE_QUEUED:
+	case STATE_ACTIVE:
+		b->flags |= V4L2_BUF_FLAG_QUEUED;
+		break;
+	case STATE_DONE:
+	case STATE_ERROR:
+		b->flags |= V4L2_BUF_FLAG_DONE;
+		break;
+	case STATE_NEEDS_INIT:
+	case STATE_IDLE:
+		/* nothing */
+		break;
+	}
+
+	if (vb->input != UNSET) {
+		b->flags |= V4L2_BUF_FLAG_INPUT;
+		b->input  = vb->input;
+	}
+
+	b->field     = vb->field;
+	b->timestamp = vb->ts;
+	b->bytesused = vb->size;
+	b->sequence  = vb->field_count >> 1;
+}
+
+int
+videobuf_reqbufs(struct videobuf_queue *q,
+		 struct v4l2_requestbuffers *req)
+{
+	unsigned int size,count;
+	int retval;
+
+	if (req->type != q->type)
+		return -EINVAL;
+	if (req->count < 1)
+		return -EINVAL;
+	if (req->memory != V4L2_MEMORY_MMAP     &&
+	    req->memory != V4L2_MEMORY_USERPTR  &&
+	    req->memory != V4L2_MEMORY_OVERLAY)
+		return -EINVAL;
+
+	if (q->streaming)
+		return -EBUSY;
+	if (!list_empty(&q->stream))
+		return -EBUSY;
+
+	down(&q->lock);
+	count = req->count;
+	if (count > VIDEO_MAX_FRAME)
+		count = VIDEO_MAX_FRAME;
+	size = 0;
+	q->ops->buf_setup(q,&count,&size);
+	size = PAGE_ALIGN(size);
+	dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
+		count, size, (count*size)>>PAGE_SHIFT);
+
+	retval = videobuf_mmap_setup(q,count,size,req->memory);
+	if (retval < 0)
+		goto done;
+
+	req->count = count;
+
+ done:
+	up(&q->lock);
+	return retval;
+}
+
+int
+videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
+{
+	if (unlikely(b->type != q->type))
+		return -EINVAL;
+	if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME))
+		return -EINVAL;
+	if (unlikely(NULL == q->bufs[b->index]))
+		return -EINVAL;
+	videobuf_status(b,q->bufs[b->index],q->type);
+	return 0;
+}
+
+int
+videobuf_qbuf(struct videobuf_queue *q,
+	      struct v4l2_buffer *b)
+{
+	struct videobuf_buffer *buf;
+	enum v4l2_field field;
+	unsigned long flags;
+	int retval;
+
+	down(&q->lock);
+	retval = -EBUSY;
+	if (q->reading)
+		goto done;
+	retval = -EINVAL;
+	if (b->type != q->type)
+		goto done;
+	if (b->index < 0 || b->index >= VIDEO_MAX_FRAME)
+		goto done;
+	buf = q->bufs[b->index];
+	if (NULL == buf)
+		goto done;
+	MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
+	if (buf->memory != b->memory)
+		goto done;
+	if (buf->state == STATE_QUEUED ||
+	    buf->state == STATE_ACTIVE)
+		goto done;
+
+	if (b->flags & V4L2_BUF_FLAG_INPUT) {
+		if (b->input >= q->inputs)
+			goto done;
+		buf->input = b->input;
+	} else {
+		buf->input = UNSET;
+	}
+
+	switch (b->memory) {
+	case V4L2_MEMORY_MMAP:
+		if (0 == buf->baddr)
+			goto done;
+		break;
+	case V4L2_MEMORY_USERPTR:
+		if (b->length < buf->bsize)
+			goto done;
+		if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
+			q->ops->buf_release(q,buf);
+		buf->baddr = b->m.userptr;
+		break;
+	case V4L2_MEMORY_OVERLAY:
+		buf->boff = b->m.offset;
+		break;
+	default:
+		goto done;
+	}
+
+	field = videobuf_next_field(q);
+	retval = q->ops->buf_prepare(q,buf,field);
+	if (0 != retval)
+		goto done;
+
+	list_add_tail(&buf->stream,&q->stream);
+	if (q->streaming) {
+		spin_lock_irqsave(q->irqlock,flags);
+		q->ops->buf_queue(q,buf);
+		spin_unlock_irqrestore(q->irqlock,flags);
+	}
+	retval = 0;
+
+ done:
+	up(&q->lock);
+	return retval;
+}
+
+int
+videobuf_dqbuf(struct videobuf_queue *q,
+	       struct v4l2_buffer *b, int nonblocking)
+{
+	struct videobuf_buffer *buf;
+	int retval;
+
+	down(&q->lock);
+	retval = -EBUSY;
+	if (q->reading)
+		goto done;
+	retval = -EINVAL;
+	if (b->type != q->type)
+		goto done;
+	if (list_empty(&q->stream))
+		goto done;
+	buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
+	retval = videobuf_waiton(buf, nonblocking, 1);
+	if (retval < 0)
+		goto done;
+	switch (buf->state) {
+	case STATE_ERROR:
+		retval = -EIO;
+		/* fall through */
+	case STATE_DONE:
+		videobuf_dma_pci_sync(q->pci,&buf->dma);
+		buf->state = STATE_IDLE;
+		break;
+	default:
+		retval = -EINVAL;
+		goto done;
+	}
+	list_del(&buf->stream);
+	memset(b,0,sizeof(*b));
+	videobuf_status(b,buf,q->type);
+
+ done:
+	up(&q->lock);
+	return retval;
+}
+
+int videobuf_streamon(struct videobuf_queue *q)
+{
+	struct videobuf_buffer *buf;
+	struct list_head *list;
+	unsigned long flags;
+	int retval;
+
+	down(&q->lock);
+	retval = -EBUSY;
+	if (q->reading)
+		goto done;
+	retval = 0;
+	if (q->streaming)
+		goto done;
+	q->streaming = 1;
+	spin_lock_irqsave(q->irqlock,flags);
+	list_for_each(list,&q->stream) {
+		buf = list_entry(list, struct videobuf_buffer, stream);
+		if (buf->state == STATE_PREPARED)
+			q->ops->buf_queue(q,buf);
+	}
+	spin_unlock_irqrestore(q->irqlock,flags);
+
+ done:
+	up(&q->lock);
+	return retval;
+}
+
+int videobuf_streamoff(struct videobuf_queue *q)
+{
+	int retval = -EINVAL;
+
+	down(&q->lock);
+	if (!q->streaming)
+		goto done;
+	videobuf_queue_cancel(q);
+	q->streaming = 0;
+	retval = 0;
+
+ done:
+	up(&q->lock);
+	return retval;
+}
+
+static ssize_t
+videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
+		       size_t count, loff_t *ppos)
+{
+	enum v4l2_field field;
+	unsigned long flags;
+        int retval;
+
+        /* setup stuff */
+	retval = -ENOMEM;
+	q->read_buf = videobuf_alloc(q->msize);
+	if (NULL == q->read_buf)
+		goto done;
+
+	q->read_buf->memory = V4L2_MEMORY_USERPTR;
+	q->read_buf->baddr  = (unsigned long)data;
+        q->read_buf->bsize  = count;
+	field = videobuf_next_field(q);
+	retval = q->ops->buf_prepare(q,q->read_buf,field);
+	if (0 != retval)
+		goto done;
+
+        /* start capture & wait */
+	spin_lock_irqsave(q->irqlock,flags);
+	q->ops->buf_queue(q,q->read_buf);
+	spin_unlock_irqrestore(q->irqlock,flags);
+        retval = videobuf_waiton(q->read_buf,0,0);
+        if (0 == retval) {
+		videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
+		if (STATE_ERROR == q->read_buf->state)
+			retval = -EIO;
+		else
+			retval = q->read_buf->size;
+	}
+
+ done:
+	/* cleanup */
+	q->ops->buf_release(q,q->read_buf);
+	kfree(q->read_buf);
+	q->read_buf = NULL;
+	return retval;
+}
+
+ssize_t videobuf_read_one(struct videobuf_queue *q,
+			  char __user *data, size_t count, loff_t *ppos,
+			  int nonblocking)
+{
+	enum v4l2_field field;
+	unsigned long flags;
+	unsigned size, nbufs, bytes;
+	int retval;
+
+	down(&q->lock);
+
+	nbufs = 1; size = 0;
+	q->ops->buf_setup(q,&nbufs,&size);
+	if (NULL == q->read_buf  &&
+	    count >= size        &&
+	    !nonblocking) {
+		retval = videobuf_read_zerocopy(q,data,count,ppos);
+		if (retval >= 0  ||  retval == -EIO)
+			/* ok, all done */
+			goto done;
+		/* fallback to kernel bounce buffer on failures */
+	}
+
+	if (NULL == q->read_buf) {
+		/* need to capture a new frame */
+		retval = -ENOMEM;
+		q->read_buf = videobuf_alloc(q->msize);
+		if (NULL == q->read_buf)
+			goto done;
+		q->read_buf->memory = V4L2_MEMORY_USERPTR;
+		field = videobuf_next_field(q);
+		retval = q->ops->buf_prepare(q,q->read_buf,field);
+		if (0 != retval)
+			goto done;
+		spin_lock_irqsave(q->irqlock,flags);
+		q->ops->buf_queue(q,q->read_buf);
+		spin_unlock_irqrestore(q->irqlock,flags);
+		q->read_off = 0;
+	}
+
+	/* wait until capture is done */
+        retval = videobuf_waiton(q->read_buf, nonblocking, 1);
+	if (0 != retval)
+		goto done;
+	videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
+
+	if (STATE_ERROR == q->read_buf->state) {
+		/* catch I/O errors */
+		q->ops->buf_release(q,q->read_buf);
+		kfree(q->read_buf);
+		q->read_buf = NULL;
+		retval = -EIO;
+		goto done;
+	}
+
+	/* copy to userspace */
+	bytes = count;
+	if (bytes > q->read_buf->size - q->read_off)
+		bytes = q->read_buf->size - q->read_off;
+	retval = -EFAULT;
+	if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
+		goto done;
+
+	retval = bytes;
+	q->read_off += bytes;
+	if (q->read_off == q->read_buf->size) {
+		/* all data copied, cleanup */
+		q->ops->buf_release(q,q->read_buf);
+		kfree(q->read_buf);
+		q->read_buf = NULL;
+	}
+
+ done:
+	up(&q->lock);
+	return retval;
+}
+
+int videobuf_read_start(struct videobuf_queue *q)
+{
+	enum v4l2_field field;
+	unsigned long flags;
+	int count = 0, size = 0;
+	int err, i;
+
+	q->ops->buf_setup(q,&count,&size);
+	if (count < 2)
+		count = 2;
+	if (count > VIDEO_MAX_FRAME)
+		count = VIDEO_MAX_FRAME;
+	size = PAGE_ALIGN(size);
+
+	err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
+	if (err)
+		return err;
+	for (i = 0; i < count; i++) {
+		field = videobuf_next_field(q);
+		err = q->ops->buf_prepare(q,q->bufs[i],field);
+		if (err)
+			return err;
+		list_add_tail(&q->bufs[i]->stream, &q->stream);
+	}
+	spin_lock_irqsave(q->irqlock,flags);
+	for (i = 0; i < count; i++)
+		q->ops->buf_queue(q,q->bufs[i]);
+	spin_unlock_irqrestore(q->irqlock,flags);
+	q->reading = 1;
+	return 0;
+}
+
+void videobuf_read_stop(struct videobuf_queue *q)
+{
+	int i;
+
+	videobuf_queue_cancel(q);
+	videobuf_mmap_free(q);
+	INIT_LIST_HEAD(&q->stream);
+	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+		if (NULL == q->bufs[i])
+			continue;
+		kfree(q->bufs[i]);
+		q->bufs[i] = NULL;
+	}
+	q->read_buf = NULL;
+	q->reading  = 0;
+}
+
+ssize_t videobuf_read_stream(struct videobuf_queue *q,
+			     char __user *data, size_t count, loff_t *ppos,
+			     int vbihack, int nonblocking)
+{
+	unsigned int *fc, bytes;
+	int err, retval;
+	unsigned long flags;
+
+	dprintk(2,"%s\n",__FUNCTION__);
+	down(&q->lock);
+	retval = -EBUSY;
+	if (q->streaming)
+		goto done;
+	if (!q->reading) {
+		retval = videobuf_read_start(q);
+		if (retval < 0)
+			goto done;
+	}
+
+	retval = 0;
+	while (count > 0) {
+		/* get / wait for data */
+		if (NULL == q->read_buf) {
+			q->read_buf = list_entry(q->stream.next,
+						 struct videobuf_buffer,
+						 stream);
+			list_del(&q->read_buf->stream);
+			q->read_off = 0;
+		}
+		err = videobuf_waiton(q->read_buf, nonblocking, 1);
+		if (err < 0) {
+			if (0 == retval)
+				retval = err;
+			break;
+		}
+
+		if (q->read_buf->state == STATE_DONE) {
+			if (vbihack) {
+				/* dirty, undocumented hack -- pass the frame counter
+				 * within the last four bytes of each vbi data block.
+				 * We need that one to maintain backward compatibility
+				 * to all vbi decoding software out there ... */
+				fc  = (unsigned int*)q->read_buf->dma.vmalloc;
+				fc += (q->read_buf->size>>2) -1;
+				*fc = q->read_buf->field_count >> 1;
+				dprintk(1,"vbihack: %d\n",*fc);
+			}
+
+			/* copy stuff */
+			bytes = count;
+			if (bytes > q->read_buf->size - q->read_off)
+				bytes = q->read_buf->size - q->read_off;
+			if (copy_to_user(data + retval,
+					 q->read_buf->dma.vmalloc + q->read_off,
+					 bytes)) {
+				if (0 == retval)
+					retval = -EFAULT;
+				break;
+			}
+			count       -= bytes;
+			retval      += bytes;
+			q->read_off += bytes;
+		} else {
+			/* some error */
+			q->read_off = q->read_buf->size;
+			if (0 == retval)
+				retval = -EIO;
+		}
+
+		/* requeue buffer when done with copying */
+		if (q->read_off == q->read_buf->size) {
+			list_add_tail(&q->read_buf->stream,
+				      &q->stream);
+			spin_lock_irqsave(q->irqlock,flags);
+			q->ops->buf_queue(q,q->read_buf);
+			spin_unlock_irqrestore(q->irqlock,flags);
+			q->read_buf = NULL;
+		}
+		if (retval < 0)
+			break;
+	}
+
+ done:
+	up(&q->lock);
+	return retval;
+}
+
+unsigned int videobuf_poll_stream(struct file *file,
+				  struct videobuf_queue *q,
+				  poll_table *wait)
+{
+	struct videobuf_buffer *buf = NULL;
+	unsigned int rc = 0;
+
+	down(&q->lock);
+	if (q->streaming) {
+		if (!list_empty(&q->stream))
+			buf = list_entry(q->stream.next,
+					 struct videobuf_buffer, stream);
+	} else {
+		if (!q->reading)
+			videobuf_read_start(q);
+		if (!q->reading) {
+			rc = POLLERR;
+		} else if (NULL == q->read_buf) {
+			q->read_buf = list_entry(q->stream.next,
+						 struct videobuf_buffer,
+						 stream);
+			list_del(&q->read_buf->stream);
+			q->read_off = 0;
+		}
+		buf = q->read_buf;
+	}
+	if (!buf)
+		rc = POLLERR;
+
+	if (0 == rc) {
+		poll_wait(file, &buf->done, wait);
+		if (buf->state == STATE_DONE ||
+		    buf->state == STATE_ERROR)
+			rc = POLLIN|POLLRDNORM;
+	}
+	up(&q->lock);
+	return rc;
+}
+
+/* --------------------------------------------------------------------- */
+
+static void
+videobuf_vm_open(struct vm_area_struct *vma)
+{
+	struct videobuf_mapping *map = vma->vm_private_data;
+
+	dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
+		map->count,vma->vm_start,vma->vm_end);
+	map->count++;
+}
+
+static void
+videobuf_vm_close(struct vm_area_struct *vma)
+{
+	struct videobuf_mapping *map = vma->vm_private_data;
+	struct videobuf_queue *q = map->q;
+	int i;
+
+	dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
+		map->count,vma->vm_start,vma->vm_end);
+
+	map->count--;
+	if (0 == map->count) {
+		dprintk(1,"munmap %p q=%p\n",map,q);
+		down(&q->lock);
+		for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+			if (NULL == q->bufs[i])
+				continue;
+			if (q->bufs[i])
+				;
+			if (q->bufs[i]->map != map)
+				continue;
+			q->bufs[i]->map   = NULL;
+			q->bufs[i]->baddr = 0;
+			q->ops->buf_release(q,q->bufs[i]);
+		}
+		up(&q->lock);
+		kfree(map);
+	}
+	return;
+}
+
+/*
+ * Get a anonymous page for the mapping.  Make sure we can DMA to that
+ * memory location with 32bit PCI devices (i.e. don't use highmem for
+ * now ...).  Bounce buffers don't work very well for the data rates
+ * video capture has.
+ */
+static struct page*
+videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
+		   int *type)
+{
+	struct page *page;
+
+	dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
+		vaddr,vma->vm_start,vma->vm_end);
+        if (vaddr > vma->vm_end)
+		return NOPAGE_SIGBUS;
+	page = alloc_page(GFP_USER);
+	if (!page)
+		return NOPAGE_OOM;
+	clear_user_page(page_address(page), vaddr, page);
+	if (type)
+		*type = VM_FAULT_MINOR;
+	return page;
+}
+
+static struct vm_operations_struct videobuf_vm_ops =
+{
+	.open     = videobuf_vm_open,
+	.close    = videobuf_vm_close,
+	.nopage   = videobuf_vm_nopage,
+};
+
+int videobuf_mmap_setup(struct videobuf_queue *q,
+			unsigned int bcount, unsigned int bsize,
+			enum v4l2_memory memory)
+{
+	unsigned int i;
+	int err;
+
+	err = videobuf_mmap_free(q);
+	if (0 != err)
+		return err;
+
+	for (i = 0; i < bcount; i++) {
+		q->bufs[i] = videobuf_alloc(q->msize);
+		q->bufs[i]->i      = i;
+		q->bufs[i]->input  = UNSET;
+		q->bufs[i]->memory = memory;
+		q->bufs[i]->bsize  = bsize;
+		switch (memory) {
+		case V4L2_MEMORY_MMAP:
+			q->bufs[i]->boff  = bsize * i;
+			break;
+		case V4L2_MEMORY_USERPTR:
+		case V4L2_MEMORY_OVERLAY:
+			/* nothing */
+			break;
+		}
+	}
+	dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
+		bcount,bsize);
+	return 0;
+}
+
+int videobuf_mmap_free(struct videobuf_queue *q)
+{
+	int i;
+
+	for (i = 0; i < VIDEO_MAX_FRAME; i++)
+		if (q->bufs[i] && q->bufs[i]->map)
+			return -EBUSY;
+	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+		if (NULL == q->bufs[i])
+			continue;
+		q->ops->buf_release(q,q->bufs[i]);
+		kfree(q->bufs[i]);
+		q->bufs[i] = NULL;
+	}
+	return 0;
+}
+
+int videobuf_mmap_mapper(struct videobuf_queue *q,
+			 struct vm_area_struct *vma)
+{
+	struct videobuf_mapping *map;
+	unsigned int first,last,size,i;
+	int retval;
+
+	down(&q->lock);
+	retval = -EINVAL;
+	if (!(vma->vm_flags & VM_WRITE)) {
+		dprintk(1,"mmap app bug: PROT_WRITE please\n");
+		goto done;
+	}
+	if (!(vma->vm_flags & VM_SHARED)) {
+		dprintk(1,"mmap app bug: MAP_SHARED please\n");
+		goto done;
+	}
+
+	/* look for first buffer to map */
+	for (first = 0; first < VIDEO_MAX_FRAME; first++) {
+		if (NULL == q->bufs[first])
+			continue;
+		if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
+			continue;
+		if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
+			break;
+	}
+	if (VIDEO_MAX_FRAME == first) {
+		dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
+			(vma->vm_pgoff << PAGE_SHIFT));
+		goto done;
+	}
+
+	/* look for last buffer to map */
+	for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
+		if (NULL == q->bufs[last])
+			continue;
+		if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
+			continue;
+		if (q->bufs[last]->map) {
+			retval = -EBUSY;
+			goto done;
+		}
+		size += q->bufs[last]->bsize;
+		if (size == (vma->vm_end - vma->vm_start))
+			break;
+	}
+	if (VIDEO_MAX_FRAME == last) {
+		dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
+			(vma->vm_end - vma->vm_start));
+		goto done;
+	}
+
+	/* create mapping + update buffer list */
+	retval = -ENOMEM;
+	map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
+	if (NULL == map)
+		goto done;
+	for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
+		q->bufs[i]->map   = map;
+		q->bufs[i]->baddr = vma->vm_start + size;
+	}
+	map->count    = 1;
+	map->start    = vma->vm_start;
+	map->end      = vma->vm_end;
+	map->q        = q;
+	vma->vm_ops   = &videobuf_vm_ops;
+	vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
+	vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
+	vma->vm_private_data = map;
+	dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
+		map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
+	retval = 0;
+
+ done:
+	up(&q->lock);
+	return retval;
+}
+
+/* --------------------------------------------------------------------- */
+
+EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
+
+EXPORT_SYMBOL_GPL(videobuf_dma_init);
+EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
+EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
+EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
+EXPORT_SYMBOL_GPL(videobuf_dma_pci_map);
+EXPORT_SYMBOL_GPL(videobuf_dma_pci_sync);
+EXPORT_SYMBOL_GPL(videobuf_dma_pci_unmap);
+EXPORT_SYMBOL_GPL(videobuf_dma_free);
+
+EXPORT_SYMBOL_GPL(videobuf_alloc);
+EXPORT_SYMBOL_GPL(videobuf_waiton);
+EXPORT_SYMBOL_GPL(videobuf_iolock);
+
+EXPORT_SYMBOL_GPL(videobuf_queue_init);
+EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
+EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
+
+EXPORT_SYMBOL_GPL(videobuf_next_field);
+EXPORT_SYMBOL_GPL(videobuf_status);
+EXPORT_SYMBOL_GPL(videobuf_reqbufs);
+EXPORT_SYMBOL_GPL(videobuf_querybuf);
+EXPORT_SYMBOL_GPL(videobuf_qbuf);
+EXPORT_SYMBOL_GPL(videobuf_dqbuf);
+EXPORT_SYMBOL_GPL(videobuf_streamon);
+EXPORT_SYMBOL_GPL(videobuf_streamoff);
+
+EXPORT_SYMBOL_GPL(videobuf_read_start);
+EXPORT_SYMBOL_GPL(videobuf_read_stop);
+EXPORT_SYMBOL_GPL(videobuf_read_stream);
+EXPORT_SYMBOL_GPL(videobuf_read_one);
+EXPORT_SYMBOL_GPL(videobuf_poll_stream);
+
+EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
+EXPORT_SYMBOL_GPL(videobuf_mmap_free);
+EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
+
+/*
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */