Commit 87b9ad07 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab
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V4L/DVB (6254): Add videobuf-vmalloc



Adds a newer videobuf-vmalloc module. This module uses the same
videobuf controls, but implements memory allocation based on vmalloc
methods.

With this method, an USB driver can use video-buf, without needing to
request memory from the DMA-safe area.
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@infradead.org>
parent 6bb2790f
......@@ -134,6 +134,10 @@ config VIDEOBUF_DMA_SG
select VIDEOBUF_GEN
tristate
config VIDEOBUF_VMALLOC
select VIDEOBUF_GEN
tristate
config VIDEO_BUF_DVB
tristate
......
......@@ -364,7 +364,7 @@ endmenu # encoder / decoder chips
config VIDEO_VIVI
tristate "Virtual Video Driver"
depends on VIDEO_V4L2 && !SPARC32 && !SPARC64 && PCI
select VIDEOBUF_DMA_SG
select VIDEOBUF_VMALLOC
default n
---help---
Enables a virtual video driver. This device shows a color bar
......
......@@ -89,6 +89,7 @@ obj-$(CONFIG_TUNER_TEA5761) += tea5761.o
obj-$(CONFIG_VIDEOBUF_GEN) += videobuf-core.o
obj-$(CONFIG_VIDEOBUF_DMA_SG) += videobuf-dma-sg.o
obj-$(CONFIG_VIDEOBUF_VMALLOC) += videobuf-vmalloc.o
obj-$(CONFIG_VIDEO_BUF_DVB) += video-buf-dvb.o
obj-$(CONFIG_VIDEO_BTCX) += btcx-risc.o
obj-$(CONFIG_VIDEO_TVEEPROM) += tveeprom.o
......
/*
* helper functions for vmalloc 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>
*
* 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-vmalloc.h>
#define MAGIC_DMABUF 0x17760309
#define MAGIC_VMAL_MEM 0x18221223
#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 vmalloc 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)
/***************************************************************************/
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_vmalloc_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_VMAL_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;
}
static struct vm_operations_struct videobuf_vm_ops =
{
.open = videobuf_vm_open,
.close = videobuf_vm_close,
};
/* ---------------------------------------------------------------------
* vmalloc 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_vmalloc_memory *mem;
struct videobuf_buffer *vb;
vb = kzalloc(size+sizeof(*mem),GFP_KERNEL);
mem = vb->priv = ((char *)vb)+size;
mem->magic=MAGIC_VMAL_MEM;
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 pages;
struct videbuf_vmalloc_memory *mem=vb->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
/* Currently, doesn't support V4L2_MEMORY_OVERLAY */
if ((vb->memory != V4L2_MEMORY_MMAP) &&
(vb->memory != V4L2_MEMORY_USERPTR) ) {
printk(KERN_ERR "Method currently unsupported.\n");
return -EINVAL;
}
/* FIXME: should be tested with kernel mmap mem */
mem->vmalloc=vmalloc_user (PAGE_ALIGN(vb->size));
if (NULL == mem->vmalloc) {
dprintk(1,"vmalloc (%d pages) failed\n",pages);
return -ENOMEM;
}
dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
(unsigned long)mem->vmalloc,
pages << PAGE_SHIFT);
/* It seems that some kernel versions need to do remap *after*
the mmap() call
*/
if (mem->vma) {
int retval=remap_vmalloc_range(mem->vma, mem->vmalloc,0);
kfree(mem->vma);
mem->vma=NULL;
if (retval<0) {
dprintk(1,"mmap app bug: remap_vmalloc_range area %p error %d\n",
mem->vmalloc,retval);
return retval;
}
}
return 0;
}
static int __videobuf_sync(struct videobuf_queue *q,
struct videobuf_buffer *buf)
{
return 0;
}
static int __videobuf_mmap_free(struct videobuf_queue *q)
{
unsigned int i;
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (q->bufs[i]) {
struct videbuf_vmalloc_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_vmalloc_memory *mem;
struct videobuf_mapping *map;
unsigned int first;
int retval;
unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
if (! (vma->vm_flags & VM_WRITE) || ! (vma->vm_flags & VM_SHARED))
return -EINVAL;
/* 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 == offset)
break;
}
if (VIDEO_MAX_FRAME == first) {
dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
(vma->vm_pgoff << PAGE_SHIFT));
return -EINVAL;
}
mem=q->bufs[first]->priv;
BUG_ON (!mem);
MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
/* create mapping + update buffer list */
map = mem->map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
if (NULL == map)
return -ENOMEM;
map->start = vma->vm_start;
map->end = vma->vm_end;
map->q = q;
q->bufs[first]->baddr = vma->vm_start;
vma->vm_ops = &videobuf_vm_ops;
vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
vma->vm_private_data = map;
/* Try to remap memory */
retval=remap_vmalloc_range(vma, mem->vmalloc,0);
if (retval<0) {
dprintk(1,"mmap: postponing remap_vmalloc_range\n");
mem->vma=kmalloc(sizeof(*vma),GFP_KERNEL);
if (!mem->vma) {
kfree(map);
mem->map=NULL;
return -ENOMEM;
}
memcpy(mem->vma,vma,sizeof(*vma));
}
dprintk(1,"mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n",
map,q,vma->vm_start,vma->vm_end,
(long int) q->bufs[first]->bsize,
vma->vm_pgoff,first);
videobuf_vm_open(vma);
return (0);
}
static int __videobuf_is_mmapped (struct videobuf_buffer *buf)
{
struct videbuf_vmalloc_memory *mem=buf->priv;
BUG_ON (!mem);
MAGIC_CHECK(mem->magic,MAGIC_VMAL_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_vmalloc_memory *mem=q->read_buf->priv;
BUG_ON (!mem);
MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
BUG_ON (!mem->vmalloc);
/* 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->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_vmalloc_memory *mem=q->read_buf->priv;
BUG_ON (!mem);
MAGIC_CHECK(mem->magic,MAGIC_VMAL_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->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 qops = {
.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_queue_vmalloc_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)
{
videobuf_queue_init(q, ops, dev, irqlock, type, field, msize, priv);
q->int_ops=&qops;
}
EXPORT_SYMBOL_GPL(videobuf_queue_vmalloc_init);
void *videobuf_to_vmalloc (struct videobuf_buffer *buf)
{
struct videbuf_vmalloc_memory *mem=buf->priv;
BUG_ON (!mem);
MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
return mem->vmalloc;
}
EXPORT_SYMBOL_GPL(videobuf_to_vmalloc);
void videobuf_vmalloc_free (struct videobuf_buffer *buf)
{
struct videbuf_vmalloc_memory *mem=buf->priv;
BUG_ON (!mem);
MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
vfree(mem->vmalloc);
return;
}
EXPORT_SYMBOL_GPL(videobuf_vmalloc_free);
/*
* Local variables:
* c-basic-offset: 8
* End:
*/
/*
* helper functions for vmalloc 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>
*
* 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 <media/videobuf-core.h>
/* --------------------------------------------------------------------- */
struct videbuf_vmalloc_memory
{
u32 magic;
/* for mmap'ed buffers */
struct videobuf_mapping *map;
void *vmalloc;
/* remap_vmalloc_range seems to need to run after mmap() on some cases */
struct vm_area_struct *vma;
};
void videobuf_queue_vmalloc_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);
void *videobuf_to_vmalloc (struct videobuf_buffer *buf);
void videobuf_vmalloc_free (struct videobuf_buffer *buf);
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