Hi Christoph, On Fri, 2018-05-18 at 15:27 +0200, hch@xxxxxx wrote: > On Fri, May 18, 2018 at 01:03:46PM +0000, Alexey Brodkin wrote: > > Note mmc_get_dma_dir() is just "data->flags & MMC_DATA_WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE". > > I.e. if we're preparing for sending data dma_noncoherent_map_sg() will have DMA_TO_DEVICE which > > is quite OK for passing to dma_noncoherent_sync_sg_for_device() but in case of reading we'll have > > DMA_FROM_DEVICE which we'll pass to dma_noncoherent_sync_sg_for_device() in dma_noncoherent_map_sg(). > > > > I'd say this is not entirely correct because IMHO arch_sync_dma_for_cpu() is supposed to only be used > > in case of DMA_FROM_DEVICE and arch_sync_dma_for_device() only in case of DMA_TO_DEVICE. > > arc overrides the dir paramter of the dma_sync_single_for_device/ > dma_sync_single_for_cpu calls. My patches dropped that, and I have > restored that, and audit for the other architectures is pending. Well at least for me that's a confusion what is a reason to pass direction to function which purpose is already known. I'd say that XXX_sync_for_device() doesn't need _variable_ direction as an argument, otherwise what does that mean if we pass DMA_FROM_DEVICE to that function? > That being said the existing arc code still looks rather odd as it > didn't do the same thing for the scatterlist versions of the calls. That might easily be the case so good we caught that now and it will be fixed :) > I've thrown in a few patches into my new tree to make the sg versions > make the normal calls, and to clean up the area a bit. I'll try your newer series now, thanks! -Alexey
