/*
* DMA region bookkeeping routines
*
* Copyright (C) 2002 Maas Digital LLC
*
* This code is licensed under the GPL. See the file COPYING in the root
* directory of the kernel sources for details.
*/
#ifndef IEEE1394_DMA_H
#define IEEE1394_DMA_H
#include <linux/pci.h>
#include <asm/scatterlist.h>
/**
* struct dma_prog_region - small contiguous DMA buffer
* @kvirt: kernel virtual address
* @dev: PCI device
* @n_pages: number of kernel pages
* @bus_addr: base bus address
*
* a small, physically contiguous DMA buffer with random-access, synchronous
* usage characteristics
*/
struct dma_prog_region {
unsigned char *kvirt;
struct pci_dev *dev;
unsigned int n_pages;
dma_addr_t bus_addr;
};
/* clear out all fields but do not allocate any memory */
void dma_prog_region_init(struct dma_prog_region *prog);
int dma_prog_region_alloc(struct dma_prog_region *prog, unsigned long n_bytes,
struct pci_dev *dev);
void dma_prog_region_free(struct dma_prog_region *prog);
static inline dma_addr_t dma_prog_region_offset_to_bus(
struct dma_prog_region *prog, unsigned long offset)
{
return prog->bus_addr + offset;
}
/**
* struct dma_region - large non-contiguous DMA buffer
* @virt: kernel virtual address
* @dev: PCI device
* @n_pages: number of kernel pages
* @n_dma_pages: number of IOMMU pages
* @sglist: IOMMU mapping
* @direction: PCI_DMA_TODEVICE, etc.
*
* a large, non-physically-contiguous DMA buffer with streaming, asynchronous
* usage characteristics
*/
struct dma_region {
unsigned char *kvirt;
struct pci_dev *dev;
unsigned int n_pages;
unsigned int n_dma_pages;
struct scatterlist *sglist;
int direction;
};
/* clear out all fields but do not allocate anything */
void dma_region_init(struct dma_region *dma);
/* allocate the buffer and map it to the IOMMU */
int dma_region_alloc(struct dma_region *dma, unsigned long n_bytes,
struct pci_dev *dev, int direction);
/* unmap and free the buffer */
void dma_region_free(struct dma_region *dma);
/* sync the CPU's view of the buffer */
void dma_region_sync_for_cpu(struct dma_region *dma, unsigned long offset,
unsigned long len);
/* sync the IO bus' view of the buffer */
void dma_region_sync_for_device(struct dma_region *dma, unsigned long offset,
unsigned long len);
/* map the buffer into a user space process */
int dma_region_mmap(struct dma_region *dma, struct file *file,
struct vm_area_struct *vma);
/* macro to index into a DMA region (or dma_prog_region) */
#define dma_region_i(_dma, _type, _index) \
( ((_type*) ((_dma)->kvirt)) + (_index) )
/* return the DMA bus address of the byte with the given offset
* relative to the beginning of the dma_region */
dma_addr_t dma_region_offset_to_bus(struct dma_region *dma,
unsigned long offset);
#endif /* IEEE1394_DMA_H */
