WebSVN - shark - Rev 1618 - /shark/branches/xen/drivers/linuxc26/video-buf.c

/*
* 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 as
* data often must be uncompressed by the drivers).
*
* (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
*
* 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 <linuxcomp.h>

#include <linux/init.h>
#include <linux/module.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>

#ifndef TryLockPage
# include "linux/page-flags.h"
# define TryLockPage TestSetPageLocked
#endif

#include <media/video-buf.h>

static int debug = 1;

MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
MODULE_LICENSE("GPL");
MODULE_PARM(debug,"i");

#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]))
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;
}
*/
int videobuf_lock(struct page **pages, int nr_pages)
{
int i = 0;

dprintk(2,"lock start ...\n");
//for (i = 0; i < nr_pages; i++)
// if (TryLockPage(pages[i]))
// goto err;
dprintk(2,"lock ok [%d pages]\n",nr_pages);
return 0;

// err:
dprintk(2,"lock failed, unlock ...\n");
while (i > 0)
//unlock_page(pages[--i]);
dprintk(2,"lock quit\n");
return -EINVAL;
}

int videobuf_unlock(struct page **pages, int nr_pages)
{
//int i;

dprintk(2,"unlock start ...\n");
//for (i = 0; i < nr_pages; i++)
// unlock_page(pages[i]);
dprintk(2,"unlock ok [%d pages]\n",nr_pages);
return 0;
}

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

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 = dma->nr_pages;//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)
{
int err;

if (0 == dma->nr_pages)
BUG();

if (dma->pages) {
if (0 != (err = videobuf_lock(dma->pages, dma->nr_pages))) {
dprintk(1,"videobuf_lock: %d\n",err);
return err;
}
dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
dma->offset);
if (NULL == dma->sglist)
videobuf_unlock(dma->pages, dma->nr_pages);
}
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);
return 0;
}

int videobuf_dma_pci_sync(struct pci_dev *dev, struct videobuf_dmabuf *dma)
{
if (!dma->sglen)
BUG();

if (!dma->bus_addr)
pci_dma_sync_sg(dev,dma->sglist,dma->nr_pages,dma->direction);
return 0;
}

int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma)
{
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;
if (dma->pages)
videobuf_unlock(dma->pages, dma->nr_pages);
return 0;
}

int videobuf_dma_free(struct videobuf_dmabuf *dma)
{
if (dma->sglen)
BUG();

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);
//init_waitqueue_head(&vb->done);
}
return vb;
}

int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
{
int retval = 0;
/*
DECLARE_WAITQUEUE(wait, current);

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;

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 = 0;//videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
// pages);
if (0 != err)
return err;
} else {
/* dma directly to userspace */
err = 0;//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 = 0;//videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
// bus, pages);
if (0 != err)
return err;
break;
default:
BUG();
}
err = 0;//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)
{
memset(q,0,sizeof(*q));

q->irqlock = irqlock;
q->pci = pci;
q->type = type;
q->field = field;
q->msize = msize;
q->ops = ops;

//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 file *file, 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(file,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)
{
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;
}

b->field = vb->field;
b->timestamp = vb->ts;
b->bytesused = vb->size;
b->sequence = vb->field_count >> 1;
}

int
videobuf_reqbufs(struct file *file, 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;

//down(&q->lock);
count = req->count;
if (count > VIDEO_MAX_FRAME)
count = VIDEO_MAX_FRAME;
size = 0;
q->ops->buf_setup(file,&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(file,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 file *file, 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;
if (buf->memory != b->memory)
goto done;
if (buf->state == STATE_QUEUED ||
buf->state == STATE_ACTIVE)
goto done;

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;
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(file,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(file,buf);
spin_unlock_irqrestore(q->irqlock,flags);
}
retval = 0;

done:
//up(&q->lock);
return retval;
}

int
videobuf_dqbuf(struct file *file, struct videobuf_queue *q,
struct v4l2_buffer *b)
{
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, file->f_flags & O_NONBLOCK, 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 file *file, 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(file,buf);
}
spin_unlock_irqrestore(q->irqlock,flags);

done:
//up(&q->lock);
return retval;
}

int videobuf_streamoff(struct file *file, struct videobuf_queue *q)
{
int retval = -EINVAL;

//down(&q->lock);
if (!q->streaming)
goto done;
videobuf_queue_cancel(file,q);
q->streaming = 0;
retval = 0;

done:
//up(&q->lock);
return retval;
}

static ssize_t
videobuf_read_zerocopy(struct file *file, struct videobuf_queue *q,
char *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(file,q->read_buf,field);
if (0 != retval)
goto done;

/* start capture & wait */
spin_lock_irqsave(q->irqlock,flags);
q->ops->buf_queue(file,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(file,q->read_buf);
kfree(q->read_buf);
q->read_buf = NULL;
return retval;
}

ssize_t videobuf_read_one(struct file *file, struct videobuf_queue *q,
char *data, size_t count, loff_t *ppos)
{
enum v4l2_field field;
unsigned long flags;
unsigned size, nbufs, bytes;
int retval;

//down(&q->lock);

nbufs = 1; size = 0;
q->ops->buf_setup(file,&nbufs,&size);
if (NULL == q->read_buf &&
count >= size &&
!(file->f_flags & O_NONBLOCK)) {
retval = videobuf_read_zerocopy(file,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(file,q->read_buf,field);
if (0 != retval)
goto done;
spin_lock_irqsave(q->irqlock,flags);
q->ops->buf_queue(file,q->read_buf);
spin_unlock_irqrestore(q->irqlock,flags);
q->read_off = 0;
}

/* wait until capture is done */
retval = videobuf_waiton(q->read_buf, file->f_flags & O_NONBLOCK, 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(file,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(file,q->read_buf);
kfree(q->read_buf);
q->read_buf = NULL;
}

done:
//up(&q->lock);
return retval;
}

int videobuf_read_start(struct file *file, struct videobuf_queue *q)
{
enum v4l2_field field;
unsigned long flags;
int count = 0, size = 0;
int err, i;

q->ops->buf_setup(file,&count,&size);
if (count < 2)
count = 2;
if (count > VIDEO_MAX_FRAME)
count = VIDEO_MAX_FRAME;
size = PAGE_ALIGN(size);

err = videobuf_mmap_setup(file, 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(file,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(file,q->bufs[i]);
spin_unlock_irqrestore(q->irqlock,flags);
q->reading = 1;
return 0;
}

void videobuf_read_stop(struct file *file, struct videobuf_queue *q)
{
int i;

videobuf_queue_cancel(file,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 file *file, struct videobuf_queue *q,
char *data, size_t count, loff_t *ppos,
int vbihack)
{
unsigned int *fc, bytes;
int err, retval;
unsigned long flags;

//down(&q->lock);
retval = -EBUSY;
if (q->streaming)
goto done;
if (!q->reading) {
retval = videobuf_read_start(file,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,
file->f_flags & O_NONBLOCK,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 -- skip buffer */
q->read_off = q->read_buf->size;
}

/* 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(file,q->read_buf);
spin_unlock_irqrestore(q->irqlock,flags);
q->read_buf = NULL;
}
}

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(file,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;
int i;

dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
map->count,vma->vm_start,vma->vm_end);

/* down(&fh->lock); FIXME */
map->count--;
if (0 == map->count) {
dprintk(1,"munmap %p\n",map);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == map->q->bufs[i])
continue;
if (map->q->bufs[i])
;
if (map->q->bufs[i]->map != map)
continue;
map->q->bufs[i]->map = NULL;
map->q->bufs[i]->baddr = 0;
map->q->ops->buf_release(vma->vm_file,map->q->bufs[i]);
}
kfree(map);
}
/* up(&fh->lock); FIXME */
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 write_access)
{
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 = kmalloc(sizeof(struct page),GFP_KERNEL);
if (!page)
return NOPAGE_OOM;
//clear_user_page(page_address(page), vaddr, page);
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 file *file, struct videobuf_queue *q,
unsigned int bcount, unsigned int bsize,
enum v4l2_memory memory)
{
unsigned int i;
int err;

err = videobuf_mmap_free(file,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]->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 file *file, 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(file,q->bufs[i]);
kfree(q->bufs[i]);
q->bufs[i] = NULL;
}
return 0;
}

int videobuf_mmap_mapper(struct vm_area_struct *vma,
struct videobuf_queue *q)
{
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;
vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
vma->vm_private_data = map;
dprintk(1,"mmap %p: %08lx-%08lx pgoff %08lx bufs %d-%d\n",
map,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_lock);
EXPORT_SYMBOL_GPL(videobuf_unlock);

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:
*/

Subversion Repositories shark

(root)/shark/branches/xen/drivers/linuxc26/video-buf.c @ 1680 - Rev 1618