| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * DMA region bookkeeping routines |
| 3 | * |
| 4 | * Copyright (C) 2002 Maas Digital LLC |
| 5 | * |
| 6 | * This code is licensed under the GPL. See the file COPYING in the root |
| 7 | * directory of the kernel sources for details. |
| 8 | */ |
| 9 | |
| 10 | #ifndef IEEE1394_DMA_H |
| 11 | #define IEEE1394_DMA_H |
| 12 | |
| 13 | #include <linux/pci.h> |
| 14 | #include <asm/scatterlist.h> |
| 15 | |
| 16 | /* struct dma_prog_region |
| 17 | |
| 18 | a small, physically-contiguous DMA buffer with random-access, |
| 19 | synchronous usage characteristics |
| 20 | */ |
| 21 | |
| 22 | struct dma_prog_region { |
| 23 | unsigned char *kvirt; /* kernel virtual address */ |
| 24 | struct pci_dev *dev; /* PCI device */ |
| 25 | unsigned int n_pages; /* # of kernel pages */ |
| 26 | dma_addr_t bus_addr; /* base bus address */ |
| 27 | }; |
| 28 | |
| 29 | /* clear out all fields but do not allocate any memory */ |
| 30 | void dma_prog_region_init(struct dma_prog_region *prog); |
| 31 | int dma_prog_region_alloc(struct dma_prog_region *prog, unsigned long n_bytes, struct pci_dev *dev); |
| 32 | void dma_prog_region_free(struct dma_prog_region *prog); |
| 33 | |
| 34 | static inline dma_addr_t dma_prog_region_offset_to_bus(struct dma_prog_region *prog, unsigned long offset) |
| 35 | { |
| 36 | return prog->bus_addr + offset; |
| 37 | } |
| 38 | |
| 39 | /* struct dma_region |
| 40 | |
| 41 | a large, non-physically-contiguous DMA buffer with streaming, |
| 42 | asynchronous usage characteristics |
| 43 | */ |
| 44 | |
| 45 | struct dma_region { |
| 46 | unsigned char *kvirt; /* kernel virtual address */ |
| 47 | struct pci_dev *dev; /* PCI device */ |
| 48 | unsigned int n_pages; /* # of kernel pages */ |
| 49 | unsigned int n_dma_pages; /* # of IOMMU pages */ |
| 50 | struct scatterlist *sglist; /* IOMMU mapping */ |
| 51 | int direction; /* PCI_DMA_TODEVICE, etc */ |
| 52 | }; |
| 53 | |
| 54 | /* clear out all fields but do not allocate anything */ |
| 55 | void dma_region_init(struct dma_region *dma); |
| 56 | |
| 57 | /* allocate the buffer and map it to the IOMMU */ |
| 58 | int dma_region_alloc(struct dma_region *dma, unsigned long n_bytes, struct pci_dev *dev, int direction); |
| 59 | |
| 60 | /* unmap and free the buffer */ |
| 61 | void dma_region_free(struct dma_region *dma); |
| 62 | |
| 63 | /* sync the CPU's view of the buffer */ |
| 64 | void dma_region_sync_for_cpu(struct dma_region *dma, unsigned long offset, unsigned long len); |
| 65 | /* sync the IO bus' view of the buffer */ |
| 66 | void dma_region_sync_for_device(struct dma_region *dma, unsigned long offset, unsigned long len); |
| 67 | |
| 68 | /* map the buffer into a user space process */ |
| 69 | int dma_region_mmap(struct dma_region *dma, struct file *file, struct vm_area_struct *vma); |
| 70 | |
| 71 | /* macro to index into a DMA region (or dma_prog_region) */ |
| 72 | #define dma_region_i(_dma, _type, _index) ( ((_type*) ((_dma)->kvirt)) + (_index) ) |
| 73 | |
| 74 | /* return the DMA bus address of the byte with the given offset |
| 75 | relative to the beginning of the dma_region */ |
| 76 | dma_addr_t dma_region_offset_to_bus(struct dma_region *dma, unsigned long offset); |
| 77 | |
| 78 | #endif /* IEEE1394_DMA_H */ |