On Wed, Aug 19, 2020 at 08:55:35AM +0200, Christoph Hellwig wrote: > When transferring DMA ownership back to the CPU there should never > be any writeback from the cache, as the buffer was owned by the > device until now. Instead it should just be invalidated for the > mapping directions where the device could have written data. > Note that the changes rely on the fact that kmap_atomic is stubbed > out for the !HIGHMEM case to simplify the code a bit. > > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > --- > arch/mips/mm/dma-noncoherent.c | 44 +++++++++++++++++++++------------- > 1 file changed, 28 insertions(+), 16 deletions(-) Acked-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]