Hi all,
commits 8133f43d and cc63b25e introduced buffer bouncing at the level of the FAT fs driver. I came across those because of printf() saying that the buffer is not aligned when I save my env in file on a FAT partition. Those messages are annoying because they lead to think that there's a problem when saving the environment. We could move them to debug() or at least indicate that's only a warning.
However I think that removing the bounce buffer mechanism altogether is better option. The alignment constraint doesn't belong at this level and indeed there are controllers that do not require it at all (those not using DMA for once). It could be moved to the block level and activated only if the driver for the controller needs it. Or it could be left to the driver of the controller do implement it.
I'm willing to prepare the patches for the modifications if you think they make sense.
Jean-Jacques