diff options
Diffstat (limited to 'drivers/ieee1394/dma.h')
-rw-r--r-- | drivers/ieee1394/dma.h | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/drivers/ieee1394/dma.h b/drivers/ieee1394/dma.h new file mode 100644 index 00000000000..061550a6fb9 --- /dev/null +++ b/drivers/ieee1394/dma.h @@ -0,0 +1,78 @@ +/* + * 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 */ |