[driver-discuss] mapping DMA memory to userspace (again)

[Joachim Worringen]

The problem of mapping memory from ddi_dma_mem_alloc() to userspace 
seems to be persistent (see 
http://forum.java.sun.com/thread.jspa?threadID=5077776 or 
http://forum.java.sun.com/thread.jspa?threadID=5077633) as something 
like devmap_dmamem_setup() is missing next to the existing 
devmap_umem_setup() and devmap_devmem_setup().

The problem with the current DDI (I use SXCE 68, but the driver should 
run on Solaris >= 10) is the missing umem-cookie to feed into 
devmap_umem_setup(). For now, I have chosen the work-around (call it 
hack) to build this cookie myself by assigning the kvaddr, size and type 
myself. This seems to work, but surely isn't pretty.

- Is there a clean workaround for this problem? How are others solving 
this problem?
- Is there a RFE for this problem, or even a targeted solution?

  Joachim

-- 
Joachim Worringen, Software Architect, Dolphin Interconnect Solutions
phone ++49/(0)228/324 08 17 - http://www.dolphinics.com