V4L/DVB (5147): Make vivi driver to use vmalloced pointers

Before this patch, vivi were simulating a scatter gather DMA transfer.
While this is academic, showing how stuff really works on a real PCI 
device, this means a non-optimized code. 
There are only two memory models that vivi implements:
	1) kernel alloced memory. This is also used by read() method.
	   On this case, a vmalloc32 buffer is allocated at kernel;
	2) userspace allocated memory. This is used by most userspace apps.
	   video-buf will store this pointer.
	   a simple copy_to_user is enough to transfer data.
The third memory model scenario supported by video-buf is overlay mode. 
This model is not implemented on vivi and unlikely to be implemented on 
newer drivers, since now, most userspace apps do some post-processing 
(like de-interlacing).
After this patch, some cleanups may be done at video-buf.c to avoid 
allocating pages, when the driver doesn't need a PCI buffer. This is the 
case of vivi and usb drivers.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Mauro Carvalho Chehab 2007-01-25 05:00:01 -03:00
parent 52ebc763d8
commit b50e7fe993
3 changed files with 78 additions and 11 deletions

View File

@ -148,6 +148,8 @@ int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
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,
@ -285,6 +287,7 @@ int videobuf_dma_free(struct videobuf_dmabuf *dma)
vfree(dma->vmalloc);
dma->vmalloc = NULL;
dma->varea = NULL;
if (dma->bus_addr) {
dma->bus_addr = 0;

View File

@ -145,7 +145,9 @@ struct vivi_buffer {
struct vivi_fmt *fmt;
#ifdef CONFIG_VIVI_SCATTER
struct sg_to_addr *to_addr;
#endif
};
struct vivi_dmaqueue {
@ -230,6 +232,7 @@ static u8 bars[8][3] = {
#define TSTAMP_MAX_Y TSTAMP_MIN_Y+15
#define TSTAMP_MIN_X 64
#ifdef CONFIG_VIVI_SCATTER
static void prep_to_addr(struct sg_to_addr to_addr[],
struct videobuf_buffer *vb)
{
@ -262,14 +265,24 @@ static int get_addr_pos(int pos, int pages, struct sg_to_addr to_addr[])
return (p1);
}
#endif
#ifdef CONFIG_VIVI_SCATTER
static void gen_line(struct sg_to_addr to_addr[],int inipos,int pages,int wmax,
int hmax, int line, char *timestr)
#else
static void gen_line(char *basep,int inipos,int wmax,
int hmax, int line, char *timestr)
#endif
{
int w,i,j,pos=inipos,pgpos,oldpg,y;
char *p,*s,*basep;
struct page *pg;
int w,i,j,pos=inipos,y;
char *p,*s;
u8 chr,r,g,b,color;
#ifdef CONFIG_VIVI_SCATTER
int pgpos,oldpg;
char *basep;
struct page *pg;
unsigned long flags;
spinlock_t spinlock;
@ -280,6 +293,7 @@ static void gen_line(struct sg_to_addr to_addr[],int inipos,int pages,int wmax,
pg=pfn_to_page(sg_dma_address(to_addr[oldpg].sg) >> PAGE_SHIFT);
spin_lock_irqsave(&spinlock,flags);
basep = kmap_atomic(pg, KM_BOUNCE_READ)+to_addr[oldpg].sg->offset;
#endif
/* We will just duplicate the second pixel at the packet */
wmax/=2;
@ -291,6 +305,7 @@ static void gen_line(struct sg_to_addr to_addr[],int inipos,int pages,int wmax,
b=bars[w*7/wmax][2];
for (color=0;color<4;color++) {
#ifdef CONFIG_VIVI_SCATTER
pgpos=get_addr_pos(pos,pages,to_addr);
if (pgpos!=oldpg) {
pg=pfn_to_page(sg_dma_address(to_addr[pgpos].sg) >> PAGE_SHIFT);
@ -299,6 +314,9 @@ static void gen_line(struct sg_to_addr to_addr[],int inipos,int pages,int wmax,
oldpg=pgpos;
}
p=basep+pos-to_addr[pgpos].pos;
#else
p=basep+pos;
#endif
switch (color) {
case 0:
@ -343,6 +361,7 @@ static void gen_line(struct sg_to_addr to_addr[],int inipos,int pages,int wmax,
pos=inipos+j*2;
for (color=0;color<4;color++) {
#ifdef CONFIG_VIVI_SCATTER
pgpos=get_addr_pos(pos,pages,to_addr);
if (pgpos!=oldpg) {
pg=pfn_to_page(sg_dma_address(
@ -356,6 +375,9 @@ static void gen_line(struct sg_to_addr to_addr[],int inipos,int pages,int wmax,
oldpg=pgpos;
}
p=basep+pos-to_addr[pgpos].pos;
#else
p=basep+pos;
#endif
y=TO_Y(r,g,b);
@ -380,19 +402,27 @@ static void gen_line(struct sg_to_addr to_addr[],int inipos,int pages,int wmax,
end:
#ifdef CONFIG_VIVI_SCATTER
kunmap_atomic(basep, KM_BOUNCE_READ);
spin_unlock_irqrestore(&spinlock,flags);
#else
return;
#endif
}
static void vivi_fillbuff(struct vivi_dev *dev,struct vivi_buffer *buf)
{
int h,pos=0;
int hmax = buf->vb.height;
int wmax = buf->vb.width;
struct videobuf_buffer *vb=&buf->vb;
struct sg_to_addr *to_addr=buf->to_addr;
struct timeval ts;
#ifdef CONFIG_VIVI_SCATTER
struct sg_to_addr *to_addr=buf->to_addr;
struct videobuf_buffer *vb=&buf->vb;
#else
char *tmpbuf;
#endif
#ifdef CONFIG_VIVI_SCATTER
/* Test if DMA mapping is ready */
if (!sg_dma_address(&vb->dma.sglist[0]))
return;
@ -401,9 +431,27 @@ static void vivi_fillbuff(struct vivi_dev *dev,struct vivi_buffer *buf)
/* Check if there is enough memory */
BUG_ON(buf->vb.dma.nr_pages << PAGE_SHIFT < (buf->vb.width*buf->vb.height)*2);
#else
if (buf->vb.dma.varea) {
tmpbuf=kmalloc (wmax*2, GFP_KERNEL);
} else {
tmpbuf=buf->vb.dma.vmalloc;
}
#endif
for (h=0;h<hmax;h++) {
#ifdef CONFIG_VIVI_SCATTER
gen_line(to_addr,pos,vb->dma.nr_pages,wmax,hmax,h,dev->timestr);
#else
if (buf->vb.dma.varea) {
gen_line(tmpbuf,0,wmax,hmax,h,dev->timestr);
/* FIXME: replacing to __copy_to_user */
copy_to_user(buf->vb.dma.varea+pos,tmpbuf,wmax*2);
} else {
gen_line(tmpbuf,pos,wmax,hmax,h,dev->timestr);
}
#endif
pos += wmax*2;
}
@ -429,7 +477,7 @@ static void vivi_fillbuff(struct vivi_dev *dev,struct vivi_buffer *buf)
dev->h,dev->m,dev->s,(dev->us+500)/1000);
dprintk(2,"vivifill at %s: Buffer 0x%08lx size= %d\n",dev->timestr,
(unsigned long)buf->vb.dma.vmalloc,pos);
(unsigned long)buf->vb.dma.varea,pos);
/* Advice that buffer was filled */
buf->vb.state = STATE_DONE;
@ -668,9 +716,11 @@ static void free_buffer(struct videobuf_queue *vq, struct vivi_buffer *buf)
if (in_interrupt())
BUG();
#ifdef CONFIG_VIVI_SCATTER
/*FIXME: Maybe a spinlock is required here */
kfree(buf->to_addr);
buf->to_addr=NULL;
#endif
videobuf_waiton(&buf->vb,0,0);
videobuf_dma_unmap(vq, &buf->vb.dma);
@ -716,11 +766,12 @@ buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
buf->vb.state = STATE_PREPARED;
#ifdef CONFIG_VIVI_SCATTER
if (NULL == (buf->to_addr = kmalloc(sizeof(*buf->to_addr) * vb->dma.nr_pages,GFP_KERNEL))) {
rc=-ENOMEM;
goto fail;
}
#endif
return 0;
fail:
@ -785,6 +836,7 @@ static void buffer_release(struct videobuf_queue *vq, struct videobuf_buffer *vb
free_buffer(vq,buf);
}
#ifdef CONFIG_VIVI_SCATTER
static int vivi_map_sg(void *dev, struct scatterlist *sg, int nents,
int direction)
{
@ -817,6 +869,7 @@ static int vivi_dma_sync_sg(void *dev,struct scatterlist *sglist, int nr_pages,
// flush_write_buffers();
return 0;
}
#endif
static struct videobuf_queue_ops vivi_video_qops = {
.buf_setup = buffer_setup,
@ -825,9 +878,9 @@ static struct videobuf_queue_ops vivi_video_qops = {
.buf_release = buffer_release,
/* Non-pci handling routines */
.vb_map_sg = vivi_map_sg,
.vb_dma_sync_sg = vivi_dma_sync_sg,
.vb_unmap_sg = vivi_unmap_sg,
// .vb_map_sg = vivi_map_sg,
// .vb_dma_sync_sg = vivi_dma_sync_sg,
// .vb_unmap_sg = vivi_unmap_sg,
};
/* ------------------------------------------------------------------
@ -1205,11 +1258,19 @@ static int vivi_open(struct inode *inode, struct file *file)
sprintf(dev->timestr,"%02d:%02d:%02d:%03d",
dev->h,dev->m,dev->s,(dev->us+500)/1000);
#ifdef CONFIG_VIVI_SCATTER
videobuf_queue_init(&fh->vb_vidq,VIDEOBUF_DMA_SCATTER, &vivi_video_qops,
NULL, NULL,
fh->type,
V4L2_FIELD_INTERLACED,
sizeof(struct vivi_buffer),fh);
#else
videobuf_queue_init(&fh->vb_vidq, &vivi_video_qops,
NULL, NULL,
fh->type,
V4L2_FIELD_INTERLACED,
sizeof(struct vivi_buffer),fh);
#endif
return 0;
}

View File

@ -78,6 +78,9 @@ struct videobuf_dmabuf {
/* for kernel buffers */
void *vmalloc;
/* Stores the userspace pointer to vmalloc area */
void *varea;
/* for overlay buffers (pci-pci dma) */
dma_addr_t bus_addr;