Hi all, The alignment in cma_alloc() is done w.r.t. the bitmap. This is a problem when, for example:
- a device requires 16M (order 12) alignment - the CMA region is not 16 M aligned In such a case, can result with the CMA region starting at, say, 0x2f800000 but any allocation you make from there will be aligned from there. Requesting an allocation of 32 M with 16 M alignment, will result in an allocation from 0x2f800000 to 0x31800000, which doesn't work very well if your strange device requires 16M alignment. This doesn't have the behavior I would expect, which would be for the allocation to be aligned w.r.t. the start of memory. I realize that aligning the CMA region is an option, but don't see why cma_alloc() aligns to the start of the CMA region. Is there a good reason for having cma_alloc() alignment work this way? Thanks and regards, Gregory -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
