dma_map(D3X)dma_map(D3X)NAMEdma_map - load DMA mapping registers for an imminent transfer
SYNOPSIS
#include "sys/types.h"
#include "sys/sema.h"
#include "sys/dmamap.h"
int dma_map(dmamap_t *dmamap,caddr_t kernel_vaddr, int num_bytes);
DESCRIPTIONdma_map attempts to map num_bytes of main memory starting at the kernel
virtual address kernel_vaddr, using the previously allocated DMA map
dmamap. dma_map determines the actual physical memory locations for the
given address and range and loads them into the mapping registers
corresponding to the map. These mapping registers remain undisturbed
until another call to dma_map.
Return Values
dma_map returns the actual number of bytes mapped. This number may be
less than that requested if the number of map registers required exceeds
the size of the given DMA map.
0 is returned if the arguments are invalid, for instance, if a
kernel_vaddr is not word aligned.
See Also
dma_mapaddr(D3X), dma_mapalloc(D3X), dma_mapfree(D3X), vme_adapter(D3X).
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