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Date: Tue, 14 Dec 2004 16:58:02 -0800
From: Julian Elischer <julian@elischer.org>
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Subject: bus_dma question
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The bus_dma man page is good. but it there documentation of how to 
extract the physical page addresses from a map? In other words, if I 
defien a tag for a device and then create a map using bus_dmamap_create, 
and then load it using bus_dmamap_load, what is the recommended method 
of extracting the list of addresses to feed into a DMA scatter_gather 
list? Looking at various drivers I'm getting more and more confused.. 
There is  a lot of home-grown s/g list
generation code out there.. is there a "right" way to do this?