[RFC 0/2] fix dma_map_sg not to do barriers for each buffer

[adharmap@codeaurora.org (adharmap at codeaurora.org)]

From: Abhijeet Dharmapurikar <adharmap@quicinc.com>

Please refer to the post here
http://lkml.org/lkml/2010/1/4/347

These changes are to introduce barrierless dma_map_area and dma_unmap_area and
use them to map the buffers in the scatterlist. For the last buffer, call
the normal dma_map_area(aka with barriers) effectively executing the barrier
at the end of the operation.

Note that the barrierless operations are implemented for few arm
architectures only and I would implement for others once these are okayed by the
community.

Abhijeet Dharmapurikar (2):
  dma: define barrierless versions of map and unmap area
  dma: fix scatter-gather api to use barrierless map/unmap functions

 arch/arm/include/asm/cacheflush.h  |    9 +++
 arch/arm/include/asm/dma-mapping.h |   82 +++++++++++++++++++++
 arch/arm/mm/cache-v3.S             |    6 ++
 arch/arm/mm/cache-v4.S             |    6 ++
 arch/arm/mm/cache-v4wb.S           |   94 +++++++++++++++++-------
 arch/arm/mm/cache-v4wt.S           |    6 ++
 arch/arm/mm/cache-v6.S             |  139 +++++++++++++++++++++++++----------
 arch/arm/mm/cache-v7.S             |  120 +++++++++++++++++++++++--------
 arch/arm/mm/dma-mapping.c          |   55 +++++++++++++--
 9 files changed, 414 insertions(+), 103 deletions(-)