WSL2-Linux-Kernel/drivers/ieee1394/dma.h

79 строки
2.7 KiB
C

/*
* 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
a small, physically-contiguous DMA buffer with random-access,
synchronous usage characteristics
*/
struct dma_prog_region {
unsigned char *kvirt; /* kernel virtual address */
struct pci_dev *dev; /* PCI device */
unsigned int n_pages; /* # of kernel pages */
dma_addr_t bus_addr; /* base bus address */
};
/* 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
a large, non-physically-contiguous DMA buffer with streaming,
asynchronous usage characteristics
*/
struct dma_region {
unsigned char *kvirt; /* kernel virtual address */
struct pci_dev *dev; /* PCI device */
unsigned int n_pages; /* # of kernel pages */
unsigned int n_dma_pages; /* # of IOMMU pages */
struct scatterlist *sglist; /* IOMMU mapping */
int direction; /* PCI_DMA_TODEVICE, etc */
};
/* 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 */