[linux-2.6-block.git] / drivers / media / video / videobuf-dma-sg.c

/*
 * helper functions for PCI DMA video4linux capture buffers
 *
 * 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.
 *
 * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org>
 *
 * Highly based on video-buf written originally by:
 * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
 * (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org>
 * (c) 2006 Ted Walther and John Sokol
 *
 * 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
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/interrupt.h>

#include <linux/pci.h>
#include <linux/vmalloc.h>
#include <linux/pagemap.h>
#include <asm/page.h>
#include <asm/pgtable.h>

#include <media/videobuf-dma-sg.h>

#define MAGIC_DMABUF 0x19721112
#define MAGIC_SG_MEM 0x17890714

#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 sg buffers");
MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
MODULE_LICENSE("GPL");

#define dprintk(level, fmt, arg...)	if (debug >= level) \
	printk(KERN_DEBUG "vbuf-sg: " fmt , ## arg)

/* --------------------------------------------------------------------- */

struct scatterlist*
videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
{
	struct scatterlist *sglist;
	struct page *pg;
	int i;

	sglist = kcalloc(nr_pages, sizeof(struct scatterlist), GFP_KERNEL);
	if (NULL == sglist)
		return NULL;
	for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
		pg = vmalloc_to_page(virt);
		if (NULL == pg)
			goto err;
		BUG_ON(PageHighMem(pg));
		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 = kcalloc(nr_pages, sizeof(*sglist), GFP_KERNEL);
	if (NULL == sglist)
		return NULL;

	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;
}

/* --------------------------------------------------------------------- */

struct videobuf_dmabuf *videobuf_to_dma (struct videobuf_buffer *buf)
{
	struct videbuf_pci_sg_memory *mem=buf->priv;
	BUG_ON (!mem);

	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);

	return &mem->dma;
}

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);

	dma->varea = (void *) data;

	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;
	}
	dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
				(unsigned long)dma->vmalloc,
				nr_pages << PAGE_SHIFT);
	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_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
{
	void                   *dev=q->dev;
	struct videobuf_dma_sg_ops *ops=q->priv_ops;

	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) {
		if (ops && ops->vb_map_sg) {
			dma->sglen = ops->vb_map_sg(dev,dma->sglist,
					dma->nr_pages, dma->direction);
		}
		if (0 == dma->sglen) {
			printk(KERN_WARNING
			       "%s: videobuf_map_sg failed\n",__FUNCTION__);
			kfree(dma->sglist);
			dma->sglist = NULL;
			dma->sglen = 0;
			return -EIO;
		}
	}
	return 0;
}

int videobuf_dma_sync(struct videobuf_queue *q,struct videobuf_dmabuf *dma)
{
	void                   *dev=q->dev;
	struct videobuf_dma_sg_ops *ops=q->priv_ops;

	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
	BUG_ON(!dma->sglen);

	if (!dma->bus_addr && ops && ops->vb_dma_sync_sg)
		ops->vb_dma_sync_sg(dev,dma->sglist,dma->nr_pages,
							dma->direction);

	return 0;
}

int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
{
	void                   *dev=q->dev;
	struct videobuf_dma_sg_ops *ops=q->priv_ops;

	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
	if (!dma->sglen)
		return 0;

	if (!dma->bus_addr && ops && ops->vb_unmap_sg)
			ops->vb_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;
	}

	vfree(dma->vmalloc);
	dma->vmalloc = NULL;
	dma->varea = NULL;

	if (dma->bus_addr) {
		dma->bus_addr = 0;
	}
	dma->direction = PCI_DMA_NONE;
	return 0;
}

/* --------------------------------------------------------------------- */

int videobuf_pci_dma_map(struct pci_dev *pci,struct videobuf_dmabuf *dma)
{
	struct videobuf_queue q;
	struct videobuf_dma_sg_ops qops;

	q.dev=pci;
	qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
	qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
	q.priv_ops = &qops;

	return (videobuf_dma_map(&q,dma));
}

int videobuf_pci_dma_unmap(struct pci_dev *pci,struct videobuf_dmabuf *dma)
{
	struct videobuf_queue q;
	struct videobuf_dma_sg_ops qops;

	q.dev=pci;
	qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
	qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
	q.priv_ops = &qops;

	return (videobuf_dma_unmap(&q,dma));
}

/* --------------------------------------------------------------------- */

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;
	struct videbuf_pci_sg_memory *mem;
	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);
		mutex_lock(&q->lock);
		for (i = 0; i < VIDEO_MAX_FRAME; i++) {
			if (NULL == q->bufs[i])
				continue;
			mem=q->bufs[i]->priv;

			if (!mem)
				continue;

			MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);

			if (mem->map != map)
				continue;
			mem->map   = NULL;
			q->bufs[i]->baddr = 0;
			q->ops->buf_release(q,q->bufs[i]);
		}
		mutex_unlock(&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 | __GFP_DMA32);
	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,
};

/* ---------------------------------------------------------------------
 * PCI handlers for the generic methods
 */

/* Allocated area consists on 3 parts:
	struct video_buffer
	struct <driver>_buffer (cx88_buffer, saa7134_buf, ...)
	struct videobuf_pci_sg_memory
 */

static void *__videobuf_alloc(size_t size)
{
	struct videbuf_pci_sg_memory *mem;
	struct videobuf_buffer *vb;

	vb = kzalloc(size+sizeof(*mem),GFP_KERNEL);

	mem = vb->priv = ((char *)vb)+size;
	mem->magic=MAGIC_SG_MEM;

	videobuf_dma_init(&mem->dma);

	dprintk(1,"%s: allocated at %p(%ld+%ld) & %p(%ld)\n",
		__FUNCTION__,vb,(long)sizeof(*vb),(long)size-sizeof(*vb),
		mem,(long)sizeof(*mem));

	return vb;
}

static int __videobuf_iolock (struct videobuf_queue* q,
			      struct videobuf_buffer *vb,
			      struct v4l2_framebuffer *fbuf)
{
	int err,pages;
	dma_addr_t bus;
	struct videbuf_pci_sg_memory *mem=vb->priv;
	BUG_ON(!mem);

	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);

	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( &mem->dma,
							PCI_DMA_FROMDEVICE,
							pages );
			if (0 != err)
				return err;
		} else {
			/* dma directly to userspace */
			err = videobuf_dma_init_user( &mem->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 */
		/*
		 * Using a double cast to avoid compiler warnings when
		 * building for PAE. Compiler doesn't like direct casting
		 * of a 32 bit ptr to 64 bit integer.
		 */
		bus   = (dma_addr_t)(unsigned long)fbuf->base + vb->boff;
		pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
		err = videobuf_dma_init_overlay(&mem->dma,PCI_DMA_FROMDEVICE,
						bus, pages);
		if (0 != err)
			return err;
		break;
	default:
		BUG();
	}
	err = videobuf_dma_map(q,&mem->dma);
	if (0 != err)
		return err;

	return 0;
}

static int __videobuf_sync(struct videobuf_queue *q,
			   struct videobuf_buffer *buf)
{
	struct videbuf_pci_sg_memory *mem=buf->priv;
	BUG_ON (!mem);
	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);

	return	videobuf_dma_sync(q,&mem->dma);
}

static int __videobuf_mmap_free(struct videobuf_queue *q)
{
	int i;

	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
		if (q->bufs[i]) {
			struct videbuf_pci_sg_memory *mem=q->bufs[i]->priv;
			if (mem && mem->map)
				return -EBUSY;
		}
	}

	return 0;
}

static int __videobuf_mmap_mapper(struct videobuf_queue *q,
			 struct vm_area_struct *vma)
{
	struct videbuf_pci_sg_memory *mem;
	struct videobuf_mapping *map;
	unsigned int first,last,size,i;
	int retval;

	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;
		mem=q->bufs[first]->priv;
		BUG_ON (!mem);
		MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);

		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;
		mem=q->bufs[last]->priv;
		if (mem->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) {
		mem=q->bufs[i]->priv;
		mem->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:
	return retval;
}

static int __videobuf_is_mmapped (struct videobuf_buffer *buf)
{
	struct videbuf_pci_sg_memory *mem=buf->priv;

	BUG_ON (!mem);
	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);

	return (mem->map)?1:0;
}

static int __videobuf_copy_to_user ( struct videobuf_queue *q,
				char __user *data, size_t count,
				int nonblocking )
{
	struct videbuf_pci_sg_memory *mem=q->read_buf->priv;
	BUG_ON (!mem);
	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);

	/* copy to userspace */
	if (count > q->read_buf->size - q->read_off)
		count = q->read_buf->size - q->read_off;

	if (copy_to_user(data, mem->dma.vmalloc+q->read_off, count))
		return -EFAULT;

	return count;
}

static int __videobuf_copy_stream ( struct videobuf_queue *q,
				char __user *data, size_t count, size_t pos,
				int vbihack, int nonblocking )
{
	unsigned int  *fc;
	struct videbuf_pci_sg_memory *mem=q->read_buf->priv;
	BUG_ON (!mem);
	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);

	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*)mem->dma.vmalloc;
		fc += (q->read_buf->size>>2) -1;
		*fc = q->read_buf->field_count >> 1;
		dprintk(1,"vbihack: %d\n",*fc);
	}

	/* copy stuff using the common method */
	count = __videobuf_copy_to_user (q,data,count,nonblocking);

	if ( (count==-EFAULT) && (0 == pos) )
		return -EFAULT;

	return count;
}

static struct videobuf_qtype_ops pci_ops = {
	.magic        = MAGIC_QTYPE_OPS,

	.alloc        = __videobuf_alloc,
	.iolock       = __videobuf_iolock,
	.sync         = __videobuf_sync,
	.mmap_free    = __videobuf_mmap_free,
	.mmap_mapper  = __videobuf_mmap_mapper,
	.is_mmapped   = __videobuf_is_mmapped,
	.copy_to_user = __videobuf_copy_to_user,
	.copy_stream  = __videobuf_copy_stream,
};

void *videobuf_pci_alloc (size_t size)
{
	struct videobuf_queue q;

	/* Required to make generic handler to call __videobuf_alloc */
	q.int_ops=&pci_ops;

	q.msize=size;

	return videobuf_alloc (&q);
}

void videobuf_queue_pci_init(struct videobuf_queue* q,
			 struct videobuf_queue_ops *ops,
			 void *dev,
			 spinlock_t *irqlock,
			 enum v4l2_buf_type type,
			 enum v4l2_field field,
			 unsigned int msize,
			 void *priv)
{
	struct videobuf_dma_sg_ops *priv_ops;

	videobuf_queue_init(q, ops, dev, irqlock, type, field, msize, priv);
	q->int_ops=&pci_ops;

	/* FIXME: the code bellow should be removed after having a proper
	 * memory allocation method for vivi and tm6000
	 */
	q->priv_ops= kzalloc(sizeof(struct videobuf_dma_sg_ops), GFP_KERNEL);
	BUG_ON (!q->priv_ops);

	priv_ops=q->priv_ops;

	/* Sets default methods for handling Scatter Gather mapping */
	priv_ops->vb_map_sg=(vb_map_sg_t *)pci_map_sg;
	priv_ops->vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
	priv_ops->vb_dma_sync_sg=(vb_map_sg_t *)pci_dma_sync_sg_for_cpu;
}

void videobuf_set_pci_ops (struct videobuf_queue* q,
				struct videobuf_dma_sg_ops *ops)
{
	kfree (q->priv_ops);

	q->priv_ops=ops;

	if (!ops)
		return;

	/* If not specified, defaults to PCI map sg */
	if (!ops->vb_map_sg)
		ops->vb_map_sg=(vb_map_sg_t *)pci_map_sg;

	if (!ops->vb_dma_sync_sg)
		ops->vb_dma_sync_sg=(vb_map_sg_t *)pci_dma_sync_sg_for_cpu;
	if (!ops->vb_unmap_sg)
		ops->vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
}


/* --------------------------------------------------------------------- */

EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);

EXPORT_SYMBOL_GPL(videobuf_to_dma);
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_map);
EXPORT_SYMBOL_GPL(videobuf_dma_sync);
EXPORT_SYMBOL_GPL(videobuf_dma_unmap);
EXPORT_SYMBOL_GPL(videobuf_dma_free);

EXPORT_SYMBOL_GPL(videobuf_pci_dma_map);
EXPORT_SYMBOL_GPL(videobuf_pci_dma_unmap);
EXPORT_SYMBOL_GPL(videobuf_pci_alloc);

EXPORT_SYMBOL_GPL(videobuf_queue_pci_init);
EXPORT_SYMBOL_GPL(videobuf_set_pci_ops);

/*
 * Local variables:
 * c-basic-offset: 8
 * End:
 */
Commit	Line	Data
7a7d9a89 MCC	1	/*
	2	* helper functions for PCI DMA video4linux capture buffers
	3	*
	4	* The functions expect the hardware being able to scatter gatter
	5	* (i.e. the buffers are not linear in physical memory, but fragmented
	6	* into PAGE_SIZE chunks). They also assume the driver does not need
	7	* to touch the video data.
	8	*
	9	* (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org>
	10	*
	11	* Highly based on video-buf written originally by:
	12	* (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
	13	* (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org>
	14	* (c) 2006 Ted Walther and John Sokol
	15	*
	16	* This program is free software; you can redistribute it and/or modify
	17	* it under the terms of the GNU General Public License as published by
	18	* the Free Software Foundation; either version 2
	19	*/
	20
	21	#include <linux/init.h>
	22	#include <linux/module.h>
	23	#include <linux/moduleparam.h>
	24	#include <linux/slab.h>
	25	#include <linux/interrupt.h>
	26
	27	#include <linux/pci.h>
	28	#include <linux/vmalloc.h>
	29	#include <linux/pagemap.h>
	30	#include <asm/page.h>
	31	#include <asm/pgtable.h>
	32
	33	#include <media/videobuf-dma-sg.h>
	34
	35	#define MAGIC_DMABUF 0x19721112
	36	#define MAGIC_SG_MEM 0x17890714
	37
	38	#define MAGIC_CHECK(is,should) if (unlikely((is) != (should))) \
	39	{ printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
	40
	41	static int debug = 0;
	42	module_param(debug, int, 0644);
	43
	44	MODULE_DESCRIPTION("helper module to manage video4linux pci dma sg buffers");
	45	MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
	46	MODULE_LICENSE("GPL");
	47
	48	#define dprintk(level, fmt, arg...) if (debug >= level) \
	49	printk(KERN_DEBUG "vbuf-sg: " fmt , ## arg)
	50
	51	/* --------------------------------------------------------------------- */
	52
	53	struct scatterlist*
	54	videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
	55	{
	56	struct scatterlist *sglist;
	57	struct page *pg;
	58	int i;
	59
	60	sglist = kcalloc(nr_pages, sizeof(struct scatterlist), GFP_KERNEL);
	61	if (NULL == sglist)
	62	return NULL;
	63	for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
	64	pg = vmalloc_to_page(virt);
65	if (NULL == pg)
66	goto err;
67	BUG_ON(PageHighMem(pg));
68	sglist[i].page = pg;
69	sglist[i].length = PAGE_SIZE;
70	}
71	return sglist;
72
73	err:
74	kfree(sglist);
75	return NULL;
76	}
77
78	struct scatterlist*
79	videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
80	{
81	struct scatterlist *sglist;
82	int i = 0;
83
84	if (NULL == pages[0])
85	return NULL;
86	sglist = kcalloc(nr_pages, sizeof(*sglist), GFP_KERNEL);
87	if (NULL == sglist)
88	return NULL;
89
90	if (NULL == pages[0])
91	goto nopage;
92	if (PageHighMem(pages[0]))
93	/* DMA to highmem pages might not work */
94	goto highmem;
95	sglist[0].page = pages[0];
96	sglist[0].offset = offset;
97	sglist[0].length = PAGE_SIZE - offset;
98	for (i = 1; i < nr_pages; i++) {
99	if (NULL == pages[i])
100	goto nopage;
101	if (PageHighMem(pages[i]))
102	goto highmem;
103	sglist[i].page = pages[i];
104	sglist[i].length = PAGE_SIZE;
105	}
106	return sglist;
107
108	nopage:
109	dprintk(2,"sgl: oops - no page\n");
110	kfree(sglist);
111	return NULL;
112
113	highmem:
114	dprintk(2,"sgl: oops - highmem page\n");
115	kfree(sglist);
116	return NULL;
117	}
118
119	/* --------------------------------------------------------------------- */
120
121	struct videobuf_dmabuf videobuf_to_dma (struct videobuf_buffer buf)
122	{
123	struct videbuf_pci_sg_memory *mem=buf->priv;
124	BUG_ON (!mem);
125
126	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
127
128	return &mem->dma;
129	}
130
131	void videobuf_dma_init(struct videobuf_dmabuf *dma)
132	{
133	memset(dma,0,sizeof(*dma));
134	dma->magic = MAGIC_DMABUF;
135	}
136
137	int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
138	unsigned long data, unsigned long size)
139	{
140	unsigned long first,last;
141	int err, rw = 0;
142
143	dma->direction = direction;
144	switch (dma->direction) {
145	case PCI_DMA_FROMDEVICE: rw = READ; break;
146	case PCI_DMA_TODEVICE: rw = WRITE; break;
147	default: BUG();
148	}
149
150	first = (data & PAGE_MASK) >> PAGE_SHIFT;
151	last = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
152	dma->offset = data & ~PAGE_MASK;
153	dma->nr_pages = last-first+1;
154	dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
155	GFP_KERNEL);
156	if (NULL == dma->pages)
157	return -ENOMEM;
158	dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
159	data,size,dma->nr_pages);
160
161	dma->varea = (void *) data;
162
163	down_read(&current->mm->mmap_sem);
164	err = get_user_pages(current,current->mm,
165	data & PAGE_MASK, dma->nr_pages,
166	rw == READ, 1, /* force */
167	dma->pages, NULL);
168	up_read(&current->mm->mmap_sem);
169	if (err != dma->nr_pages) {
170	dma->nr_pages = (err >= 0) ? err : 0;
171	dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
172	return err < 0 ? err : -EINVAL;
173	}
174	return 0;
175	}
176
177	int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
178	int nr_pages)
179	{
180	dprintk(1,"init kernel [%d pages]\n",nr_pages);
181	dma->direction = direction;
182	dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
183	if (NULL == dma->vmalloc) {
184	dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
185	return -ENOMEM;
186	}
187	dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
188	(unsigned long)dma->vmalloc,
189	nr_pages << PAGE_SHIFT);
190	memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
191	dma->nr_pages = nr_pages;
192	return 0;
193	}
194
195	int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
196	dma_addr_t addr, int nr_pages)
197	{
198	dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
199	nr_pages,(unsigned long)addr);
200	dma->direction = direction;
201	if (0 == addr)
202	return -EINVAL;
203
204	dma->bus_addr = addr;
205	dma->nr_pages = nr_pages;
206	return 0;
207	}
208
209	int videobuf_dma_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
210	{
211	void *dev=q->dev;
212	struct videobuf_dma_sg_ops *ops=q->priv_ops;
213
214	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
215	BUG_ON(0 == dma->nr_pages);
216
217	if (dma->pages) {
218	dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
219	dma->offset);
220	}
221	if (dma->vmalloc) {
222	dma->sglist = videobuf_vmalloc_to_sg
223	(dma->vmalloc,dma->nr_pages);
224	}
225	if (dma->bus_addr) {
226	dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
227	if (NULL != dma->sglist) {
228	dma->sglen = 1;
229	sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
230	dma->sglist[0].offset = dma->bus_addr & ~PAGE_MASK;
231	sg_dma_len(&dma->sglist[0]) = dma->nr_pages * PAGE_SIZE;
232	}
233	}
234	if (NULL == dma->sglist) {
235	dprintk(1,"scatterlist is NULL\n");
236	return -ENOMEM;
237	}
238	if (!dma->bus_addr) {
239	if (ops && ops->vb_map_sg) {
240	dma->sglen = ops->vb_map_sg(dev,dma->sglist,
241	dma->nr_pages, dma->direction);
242	}
243	if (0 == dma->sglen) {
244	printk(KERN_WARNING
245	"%s: videobuf_map_sg failed\n",__FUNCTION__);
246	kfree(dma->sglist);
247	dma->sglist = NULL;
248	dma->sglen = 0;
249	return -EIO;
250	}
251	}
252	return 0;
253	}
254
255	int videobuf_dma_sync(struct videobuf_queue q,struct videobuf_dmabuf dma)
256	{
257	void *dev=q->dev;
258	struct videobuf_dma_sg_ops *ops=q->priv_ops;
259
260	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
261	BUG_ON(!dma->sglen);
262
263	if (!dma->bus_addr && ops && ops->vb_dma_sync_sg)
264	ops->vb_dma_sync_sg(dev,dma->sglist,dma->nr_pages,
265	dma->direction);
266
267	return 0;
268	}
269
270	int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
271	{
272	void *dev=q->dev;
273	struct videobuf_dma_sg_ops *ops=q->priv_ops;
274
275	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
276	if (!dma->sglen)
277	return 0;
278
279	if (!dma->bus_addr && ops && ops->vb_unmap_sg)
280	ops->vb_unmap_sg(dev,dma->sglist,dma->nr_pages,
281	dma->direction);
282	kfree(dma->sglist);
283	dma->sglist = NULL;
284	dma->sglen = 0;
285	return 0;
286	}
287
288	int videobuf_dma_free(struct videobuf_dmabuf *dma)
289	{
290	MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
291	BUG_ON(dma->sglen);
292
293	if (dma->pages) {
294	int i;
295	for (i=0; i < dma->nr_pages; i++)
296	page_cache_release(dma->pages[i]);
297	kfree(dma->pages);
298	dma->pages = NULL;
299	}
300
301	vfree(dma->vmalloc);
302	dma->vmalloc = NULL;
303	dma->varea = NULL;
304
305	if (dma->bus_addr) {
306	dma->bus_addr = 0;
307	}
308	dma->direction = PCI_DMA_NONE;
309	return 0;
310	}
311
312	/* --------------------------------------------------------------------- */
313
314	int videobuf_pci_dma_map(struct pci_dev pci,struct videobuf_dmabuf dma)
315	{
316	struct videobuf_queue q;
317	struct videobuf_dma_sg_ops qops;
318
319	q.dev=pci;
320	qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
321	qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
322	q.priv_ops = &qops;
323
324	return (videobuf_dma_map(&q,dma));
325	}
326
327	int videobuf_pci_dma_unmap(struct pci_dev pci,struct videobuf_dmabuf dma)
328	{
329	struct videobuf_queue q;
330	struct videobuf_dma_sg_ops qops;
331
332	q.dev=pci;
333	qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
334	qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
335	q.priv_ops = &qops;
336
337	return (videobuf_dma_unmap(&q,dma));
338	}
339
340	/* --------------------------------------------------------------------- */
341
342	static void
343	videobuf_vm_open(struct vm_area_struct *vma)
344	{
345	struct videobuf_mapping *map = vma->vm_private_data;
346
347	dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
348	map->count,vma->vm_start,vma->vm_end);
349	map->count++;
350	}
351
352	static void
353	videobuf_vm_close(struct vm_area_struct *vma)
354	{
355	struct videobuf_mapping *map = vma->vm_private_data;
356	struct videobuf_queue *q = map->q;
357	struct videbuf_pci_sg_memory *mem;
358	int i;
359
360	dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
361	map->count,vma->vm_start,vma->vm_end);
362
363	map->count--;
364	if (0 == map->count) {
365	dprintk(1,"munmap %p q=%p\n",map,q);
366	mutex_lock(&q->lock);
367	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
368	if (NULL == q->bufs[i])
369	continue;
370	mem=q->bufs[i]->priv;
371
372	if (!mem)
373	continue;
374
375	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
376
377	if (mem->map != map)
378	continue;
379	mem->map = NULL;
380	q->bufs[i]->baddr = 0;
381	q->ops->buf_release(q,q->bufs[i]);
382	}
383	mutex_unlock(&q->lock);
384	kfree(map);
385	}
386	return;
387	}
388
389	/*
390	* Get a anonymous page for the mapping. Make sure we can DMA to that
391	* memory location with 32bit PCI devices (i.e. don't use highmem for
392	* now ...). Bounce buffers don't work very well for the data rates
393	* video capture has.
394	*/
395	static struct page*
396	videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
397	int *type)
398	{
399	struct page *page;
400
401	dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
402	vaddr,vma->vm_start,vma->vm_end);
403	if (vaddr > vma->vm_end)
404	return NOPAGE_SIGBUS;
405	page = alloc_page(GFP_USER \| __GFP_DMA32);
406	if (!page)
407	return NOPAGE_OOM;
408	clear_user_page(page_address(page), vaddr, page);
409	if (type)
410	*type = VM_FAULT_MINOR;
411	return page;
412	}
413
414	static struct vm_operations_struct videobuf_vm_ops =
415	{
416	.open = videobuf_vm_open,
417	.close = videobuf_vm_close,
418	.nopage = videobuf_vm_nopage,
419	};
420
421	/* ---------------------------------------------------------------------
422	* PCI handlers for the generic methods
423	*/
424
425	/* Allocated area consists on 3 parts:
426	struct video_buffer
427	struct <driver>_buffer (cx88_buffer, saa7134_buf, ...)
428	struct videobuf_pci_sg_memory
429	*/
430
431	static void *__videobuf_alloc(size_t size)
432	{
433	struct videbuf_pci_sg_memory *mem;
434	struct videobuf_buffer *vb;
435
436	vb = kzalloc(size+sizeof(*mem),GFP_KERNEL);
437
438	mem = vb->priv = ((char *)vb)+size;
439	mem->magic=MAGIC_SG_MEM;
440
441	videobuf_dma_init(&mem->dma);
442
443	dprintk(1,"%s: allocated at %p(%ld+%ld) & %p(%ld)\n",
444	__FUNCTION__,vb,(long)sizeof(vb),(long)size-sizeof(vb),
445	mem,(long)sizeof(*mem));
446
447	return vb;
448	}
449
450	static int __videobuf_iolock (struct videobuf_queue* q,
451	struct videobuf_buffer *vb,
452	struct v4l2_framebuffer *fbuf)
453	{
454	int err,pages;
455	dma_addr_t bus;
456	struct videbuf_pci_sg_memory *mem=vb->priv;
457	BUG_ON(!mem);
458
459	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
460
461	switch (vb->memory) {
462	case V4L2_MEMORY_MMAP:
463	case V4L2_MEMORY_USERPTR:
464	if (0 == vb->baddr) {
465	/* no userspace addr -- kernel bounce buffer */
466	pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
467	err = videobuf_dma_init_kernel( &mem->dma,
468	PCI_DMA_FROMDEVICE,
469	pages );
470	if (0 != err)
471	return err;
472	} else {
473	/* dma directly to userspace */
474	err = videobuf_dma_init_user( &mem->dma,
475	PCI_DMA_FROMDEVICE,
476	vb->baddr,vb->bsize );
477	if (0 != err)
478	return err;
479	}
480	break;
481	case V4L2_MEMORY_OVERLAY:
482	if (NULL == fbuf)
483	return -EINVAL;
484	/* FIXME: need sanity checks for vb->boff */
485	/*
486	* Using a double cast to avoid compiler warnings when
487	* building for PAE. Compiler doesn't like direct casting
488	* of a 32 bit ptr to 64 bit integer.
489	*/
490	bus = (dma_addr_t)(unsigned long)fbuf->base + vb->boff;
491	pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
492	err = videobuf_dma_init_overlay(&mem->dma,PCI_DMA_FROMDEVICE,
493	bus, pages);
494	if (0 != err)
495	return err;
496	break;
497	default:
498	BUG();
499	}
500	err = videobuf_dma_map(q,&mem->dma);
501	if (0 != err)
502	return err;
503
504	return 0;
505	}
506
507	static int __videobuf_sync(struct videobuf_queue *q,
508	struct videobuf_buffer *buf)
509	{
510	struct videbuf_pci_sg_memory *mem=buf->priv;
511	BUG_ON (!mem);
512	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
513
514	return videobuf_dma_sync(q,&mem->dma);
515	}
516
517	static int __videobuf_mmap_free(struct videobuf_queue *q)
518	{
519	int i;
520
521	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
522	if (q->bufs[i]) {
523	struct videbuf_pci_sg_memory *mem=q->bufs[i]->priv;
524	if (mem && mem->map)
525	return -EBUSY;
526	}
527	}
528
529	return 0;
530	}
531
532	static int __videobuf_mmap_mapper(struct videobuf_queue *q,
533	struct vm_area_struct *vma)
534	{
535	struct videbuf_pci_sg_memory *mem;
536	struct videobuf_mapping *map;
537	unsigned int first,last,size,i;
538	int retval;
539
540	retval = -EINVAL;
541	if (!(vma->vm_flags & VM_WRITE)) {
542	dprintk(1,"mmap app bug: PROT_WRITE please\n");
543	goto done;
544	}
545	if (!(vma->vm_flags & VM_SHARED)) {
546	dprintk(1,"mmap app bug: MAP_SHARED please\n");
547	goto done;
548	}
549
550	/* look for first buffer to map */
551	for (first = 0; first < VIDEO_MAX_FRAME; first++) {
552	if (NULL == q->bufs[first])
553	continue;
554	mem=q->bufs[first]->priv;
555	BUG_ON (!mem);
556	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
557
558	if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
559	continue;
560	if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
561	break;
562	}
563	if (VIDEO_MAX_FRAME == first) {
564	dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
565	(vma->vm_pgoff << PAGE_SHIFT));
566	goto done;
567	}
568
569	/* look for last buffer to map */
570	for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
571	if (NULL == q->bufs[last])
572	continue;
573	if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
574	continue;
575	mem=q->bufs[last]->priv;
576	if (mem->map) {
577	retval = -EBUSY;
578	goto done;
579	}
580	size += q->bufs[last]->bsize;
581	if (size == (vma->vm_end - vma->vm_start))
582	break;
583	}
584	if (VIDEO_MAX_FRAME == last) {
585	dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
586	(vma->vm_end - vma->vm_start));
587	goto done;
588	}
589
590	/* create mapping + update buffer list */
591	retval = -ENOMEM;
592	map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
593	if (NULL == map)
594	goto done;
595	for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
596	mem=q->bufs[i]->priv;
597	mem->map = map;
598	q->bufs[i]->baddr = vma->vm_start + size;
599	}
600	map->count = 1;
601	map->start = vma->vm_start;
602	map->end = vma->vm_end;
603	map->q = q;
604	vma->vm_ops = &videobuf_vm_ops;
605	vma->vm_flags \|= VM_DONTEXPAND \| VM_RESERVED;
606	vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
607	vma->vm_private_data = map;
608	dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
609	map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
610	retval = 0;
611
612	done:
613	return retval;
614	}
615
616	static int __videobuf_is_mmapped (struct videobuf_buffer *buf)
617	{
618	struct videbuf_pci_sg_memory *mem=buf->priv;
619
620	BUG_ON (!mem);
621	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
622
623	return (mem->map)?1:0;
624	}
625
626	static int __videobuf_copy_to_user ( struct videobuf_queue *q,
627	char __user *data, size_t count,
628	int nonblocking )
629	{
630	struct videbuf_pci_sg_memory *mem=q->read_buf->priv;
631	BUG_ON (!mem);
632	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
633
634	/* copy to userspace */
635	if (count > q->read_buf->size - q->read_off)
636	count = q->read_buf->size - q->read_off;
637
638	if (copy_to_user(data, mem->dma.vmalloc+q->read_off, count))
639	return -EFAULT;
640
641	return count;
642	}
643
644	static int __videobuf_copy_stream ( struct videobuf_queue *q,
645	char __user *data, size_t count, size_t pos,
646	int vbihack, int nonblocking )
647	{
648	unsigned int *fc;
649	struct videbuf_pci_sg_memory *mem=q->read_buf->priv;
650	BUG_ON (!mem);
651	MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
652
653	if (vbihack) {
654	/* dirty, undocumented hack -- pass the frame counter
655	* within the last four bytes of each vbi data block.
656	* We need that one to maintain backward compatibility
657	* to all vbi decoding software out there ... */
658	fc = (unsigned int*)mem->dma.vmalloc;
659	fc += (q->read_buf->size>>2) -1;
660	*fc = q->read_buf->field_count >> 1;
661	dprintk(1,"vbihack: %d\n",*fc);
662	}
663
664	/* copy stuff using the common method */
665	count = __videobuf_copy_to_user (q,data,count,nonblocking);
666
667	if ( (count==-EFAULT) && (0 == pos) )
668	return -EFAULT;
669
670	return count;
671	}
672
673	static struct videobuf_qtype_ops pci_ops = {
674	.magic = MAGIC_QTYPE_OPS,
675
676	.alloc = __videobuf_alloc,
677	.iolock = __videobuf_iolock,
678	.sync = __videobuf_sync,
679	.mmap_free = __videobuf_mmap_free,
680	.mmap_mapper = __videobuf_mmap_mapper,
681	.is_mmapped = __videobuf_is_mmapped,
682	.copy_to_user = __videobuf_copy_to_user,
683	.copy_stream = __videobuf_copy_stream,
684	};
685
686	void *videobuf_pci_alloc (size_t size)
687	{
688	struct videobuf_queue q;
689
690	/* Required to make generic handler to call __videobuf_alloc */
691	q.int_ops=&pci_ops;
692
693	q.msize=size;
694
695	return videobuf_alloc (&q);
696	}
697
698	void videobuf_queue_pci_init(struct videobuf_queue* q,
699	struct videobuf_queue_ops *ops,
700	void *dev,
701	spinlock_t *irqlock,
702	enum v4l2_buf_type type,
703	enum v4l2_field field,
704	unsigned int msize,
705	void *priv)
706	{
707	struct videobuf_dma_sg_ops *priv_ops;
708
709	videobuf_queue_init(q, ops, dev, irqlock, type, field, msize, priv);
710	q->int_ops=&pci_ops;
711
712	/* FIXME: the code bellow should be removed after having a proper
713	* memory allocation method for vivi and tm6000
714	*/
715	q->priv_ops= kzalloc(sizeof(struct videobuf_dma_sg_ops), GFP_KERNEL);
716	BUG_ON (!q->priv_ops);
717
718	priv_ops=q->priv_ops;
719
720	/* Sets default methods for handling Scatter Gather mapping */
721	priv_ops->vb_map_sg=(vb_map_sg_t *)pci_map_sg;
722	priv_ops->vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
723	priv_ops->vb_dma_sync_sg=(vb_map_sg_t *)pci_dma_sync_sg_for_cpu;
724	}
725
726	void videobuf_set_pci_ops (struct videobuf_queue* q,
727	struct videobuf_dma_sg_ops *ops)
728	{
729	kfree (q->priv_ops);
730
731	q->priv_ops=ops;
732
733	if (!ops)
734	return;
735
736	/* If not specified, defaults to PCI map sg */
737	if (!ops->vb_map_sg)
738	ops->vb_map_sg=(vb_map_sg_t *)pci_map_sg;
739
740	if (!ops->vb_dma_sync_sg)
741	ops->vb_dma_sync_sg=(vb_map_sg_t *)pci_dma_sync_sg_for_cpu;
742	if (!ops->vb_unmap_sg)
743	ops->vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
744	}
745
746
747	/* --------------------------------------------------------------------- */
748
749	EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
750
751	EXPORT_SYMBOL_GPL(videobuf_to_dma);
752	EXPORT_SYMBOL_GPL(videobuf_dma_init);
753	EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
754	EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
755	EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
756	EXPORT_SYMBOL_GPL(videobuf_dma_map);
757	EXPORT_SYMBOL_GPL(videobuf_dma_sync);
758	EXPORT_SYMBOL_GPL(videobuf_dma_unmap);
759	EXPORT_SYMBOL_GPL(videobuf_dma_free);
760
761	EXPORT_SYMBOL_GPL(videobuf_pci_dma_map);
762	EXPORT_SYMBOL_GPL(videobuf_pci_dma_unmap);
763	EXPORT_SYMBOL_GPL(videobuf_pci_alloc);
764
765	EXPORT_SYMBOL_GPL(videobuf_queue_pci_init);
766	EXPORT_SYMBOL_GPL(videobuf_set_pci_ops);
767
768	/*
769	* Local variables:
770	* c-basic-offset: 8
771	* End:
772	*/